1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Itypes; use Itypes;
44 with Layout; use Layout;
46 with Lib.Xref; use Lib.Xref;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Case; use Sem_Case;
56 with Sem_Cat; use Sem_Cat;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Dim; use Sem_Dim;
62 with Sem_Disp; use Sem_Disp;
63 with Sem_Dist; use Sem_Dist;
64 with Sem_Elim; use Sem_Elim;
65 with Sem_Eval; use Sem_Eval;
66 with Sem_Mech; use Sem_Mech;
67 with Sem_Res; use Sem_Res;
68 with Sem_Smem; use Sem_Smem;
69 with Sem_Type; use Sem_Type;
70 with Sem_Util; use Sem_Util;
71 with Sem_Warn; use Sem_Warn;
72 with Stand; use Stand;
73 with Sinfo; use Sinfo;
74 with Sinput; use Sinput;
75 with Snames; use Snames;
76 with Targparm; use Targparm;
77 with Tbuild; use Tbuild;
78 with Ttypes; use Ttypes;
79 with Uintp; use Uintp;
80 with Urealp; use Urealp;
82 package body Sem_Ch3 is
84 -----------------------
85 -- Local Subprograms --
86 -----------------------
88 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
89 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
90 -- abstract interface types implemented by a record type or a derived
93 procedure Build_Derived_Type
95 Parent_Type : Entity_Id;
96 Derived_Type : Entity_Id;
97 Is_Completion : Boolean;
98 Derive_Subps : Boolean := True);
99 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
100 -- the N_Full_Type_Declaration node containing the derived type definition.
101 -- Parent_Type is the entity for the parent type in the derived type
102 -- definition and Derived_Type the actual derived type. Is_Completion must
103 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
104 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
105 -- completion of a private type declaration. If Is_Completion is set to
106 -- True, N is the completion of a private type declaration and Derived_Type
107 -- is different from the defining identifier inside N (i.e. Derived_Type /=
108 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
109 -- subprograms should be derived. The only case where this parameter is
110 -- False is when Build_Derived_Type is recursively called to process an
111 -- implicit derived full type for a type derived from a private type (in
112 -- that case the subprograms must only be derived for the private view of
115 -- ??? These flags need a bit of re-examination and re-documentation:
116 -- ??? are they both necessary (both seem related to the recursion)?
118 procedure Build_Derived_Access_Type
120 Parent_Type : Entity_Id;
121 Derived_Type : Entity_Id);
122 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
123 -- create an implicit base if the parent type is constrained or if the
124 -- subtype indication has a constraint.
126 procedure Build_Derived_Array_Type
128 Parent_Type : Entity_Id;
129 Derived_Type : Entity_Id);
130 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
131 -- create an implicit base if the parent type is constrained or if the
132 -- subtype indication has a constraint.
134 procedure Build_Derived_Concurrent_Type
136 Parent_Type : Entity_Id;
137 Derived_Type : Entity_Id);
138 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
139 -- protected type, inherit entries and protected subprograms, check
140 -- legality of discriminant constraints if any.
142 procedure Build_Derived_Enumeration_Type
144 Parent_Type : Entity_Id;
145 Derived_Type : Entity_Id);
146 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
147 -- type, we must create a new list of literals. Types derived from
148 -- Character and [Wide_]Wide_Character are special-cased.
150 procedure Build_Derived_Numeric_Type
152 Parent_Type : Entity_Id;
153 Derived_Type : Entity_Id);
154 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
155 -- an anonymous base type, and propagate constraint to subtype if needed.
157 procedure Build_Derived_Private_Type
159 Parent_Type : Entity_Id;
160 Derived_Type : Entity_Id;
161 Is_Completion : Boolean;
162 Derive_Subps : Boolean := True);
163 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
164 -- because the parent may or may not have a completion, and the derivation
165 -- may itself be a completion.
167 procedure Build_Derived_Record_Type
169 Parent_Type : Entity_Id;
170 Derived_Type : Entity_Id;
171 Derive_Subps : Boolean := True);
172 -- Subsidiary procedure used for tagged and untagged record types
173 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
174 -- All parameters are as in Build_Derived_Type except that N, in
175 -- addition to being an N_Full_Type_Declaration node, can also be an
176 -- N_Private_Extension_Declaration node. See the definition of this routine
177 -- for much more info. Derive_Subps indicates whether subprograms should be
178 -- derived from the parent type. The only case where Derive_Subps is False
179 -- is for an implicit derived full type for a type derived from a private
180 -- type (see Build_Derived_Type).
182 procedure Build_Discriminal (Discrim : Entity_Id);
183 -- Create the discriminal corresponding to discriminant Discrim, that is
184 -- the parameter corresponding to Discrim to be used in initialization
185 -- procedures for the type where Discrim is a discriminant. Discriminals
186 -- are not used during semantic analysis, and are not fully defined
187 -- entities until expansion. Thus they are not given a scope until
188 -- initialization procedures are built.
190 function Build_Discriminant_Constraints
193 Derived_Def : Boolean := False) return Elist_Id;
194 -- Validate discriminant constraints and return the list of the constraints
195 -- in order of discriminant declarations, where T is the discriminated
196 -- unconstrained type. Def is the N_Subtype_Indication node where the
197 -- discriminants constraints for T are specified. Derived_Def is True
198 -- when building the discriminant constraints in a derived type definition
199 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
200 -- type and Def is the constraint "(xxx)" on T and this routine sets the
201 -- Corresponding_Discriminant field of the discriminants in the derived
202 -- type D to point to the corresponding discriminants in the parent type T.
204 procedure Build_Discriminated_Subtype
208 Related_Nod : Node_Id;
209 For_Access : Boolean := False);
210 -- Subsidiary procedure to Constrain_Discriminated_Type and to
211 -- Process_Incomplete_Dependents. Given
213 -- T (a possibly discriminated base type)
214 -- Def_Id (a very partially built subtype for T),
216 -- the call completes Def_Id to be the appropriate E_*_Subtype.
218 -- The Elist is the list of discriminant constraints if any (it is set
219 -- to No_Elist if T is not a discriminated type, and to an empty list if
220 -- T has discriminants but there are no discriminant constraints). The
221 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
222 -- The For_Access says whether or not this subtype is really constraining
223 -- an access type. That is its sole purpose is the designated type of an
224 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
225 -- is built to avoid freezing T when the access subtype is frozen.
227 function Build_Scalar_Bound
230 Der_T : Entity_Id) return Node_Id;
231 -- The bounds of a derived scalar type are conversions of the bounds of
232 -- the parent type. Optimize the representation if the bounds are literals.
233 -- Needs a more complete spec--what are the parameters exactly, and what
234 -- exactly is the returned value, and how is Bound affected???
236 procedure Build_Underlying_Full_View
240 -- If the completion of a private type is itself derived from a private
241 -- type, or if the full view of a private subtype is itself private, the
242 -- back-end has no way to compute the actual size of this type. We build
243 -- an internal subtype declaration of the proper parent type to convey
244 -- this information. This extra mechanism is needed because a full
245 -- view cannot itself have a full view (it would get clobbered during
248 procedure Check_Access_Discriminant_Requires_Limited
251 -- Check the restriction that the type to which an access discriminant
252 -- belongs must be a concurrent type or a descendant of a type with
253 -- the reserved word 'limited' in its declaration.
255 procedure Check_Anonymous_Access_Components
259 Comp_List : Node_Id);
260 -- Ada 2005 AI-382: an access component in a record definition can refer to
261 -- the enclosing record, in which case it denotes the type itself, and not
262 -- the current instance of the type. We create an anonymous access type for
263 -- the component, and flag it as an access to a component, so accessibility
264 -- checks are properly performed on it. The declaration of the access type
265 -- is placed ahead of that of the record to prevent order-of-elaboration
266 -- circularity issues in Gigi. We create an incomplete type for the record
267 -- declaration, which is the designated type of the anonymous access.
269 procedure Check_Delta_Expression (E : Node_Id);
270 -- Check that the expression represented by E is suitable for use as a
271 -- delta expression, i.e. it is of real type and is static.
273 procedure Check_Digits_Expression (E : Node_Id);
274 -- Check that the expression represented by E is suitable for use as a
275 -- digits expression, i.e. it is of integer type, positive and static.
277 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
278 -- Validate the initialization of an object declaration. T is the required
279 -- type, and Exp is the initialization expression.
281 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
282 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
284 procedure Check_Or_Process_Discriminants
287 Prev : Entity_Id := Empty);
288 -- If N is the full declaration of the completion T of an incomplete or
289 -- private type, check its discriminants (which are already known to be
290 -- conformant with those of the partial view, see Find_Type_Name),
291 -- otherwise process them. Prev is the entity of the partial declaration,
294 procedure Check_Real_Bound (Bound : Node_Id);
295 -- Check given bound for being of real type and static. If not, post an
296 -- appropriate message, and rewrite the bound with the real literal zero.
298 procedure Constant_Redeclaration
302 -- Various checks on legality of full declaration of deferred constant.
303 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
304 -- node. The caller has not yet set any attributes of this entity.
306 function Contain_Interface
308 Ifaces : Elist_Id) return Boolean;
309 -- Ada 2005: Determine whether Iface is present in the list Ifaces
311 procedure Convert_Scalar_Bounds
313 Parent_Type : Entity_Id;
314 Derived_Type : Entity_Id;
316 -- For derived scalar types, convert the bounds in the type definition to
317 -- the derived type, and complete their analysis. Given a constraint of the
318 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
319 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
320 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
321 -- subtype are conversions of those bounds to the derived_type, so that
322 -- their typing is consistent.
324 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
325 -- Copies attributes from array base type T2 to array base type T1. Copies
326 -- only attributes that apply to base types, but not subtypes.
328 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
329 -- Copies attributes from array subtype T2 to array subtype T1. Copies
330 -- attributes that apply to both subtypes and base types.
332 procedure Create_Constrained_Components
336 Constraints : Elist_Id);
337 -- Build the list of entities for a constrained discriminated record
338 -- subtype. If a component depends on a discriminant, replace its subtype
339 -- using the discriminant values in the discriminant constraint. Subt
340 -- is the defining identifier for the subtype whose list of constrained
341 -- entities we will create. Decl_Node is the type declaration node where
342 -- we will attach all the itypes created. Typ is the base discriminated
343 -- type for the subtype Subt. Constraints is the list of discriminant
344 -- constraints for Typ.
346 function Constrain_Component_Type
348 Constrained_Typ : Entity_Id;
349 Related_Node : Node_Id;
351 Constraints : Elist_Id) return Entity_Id;
352 -- Given a discriminated base type Typ, a list of discriminant constraints,
353 -- Constraints, for Typ and a component Comp of Typ, create and return the
354 -- type corresponding to Etype (Comp) where all discriminant references
355 -- are replaced with the corresponding constraint. If Etype (Comp) contains
356 -- no discriminant references then it is returned as-is. Constrained_Typ
357 -- is the final constrained subtype to which the constrained component
358 -- belongs. Related_Node is the node where we attach all created itypes.
360 procedure Constrain_Access
361 (Def_Id : in out Entity_Id;
363 Related_Nod : Node_Id);
364 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
365 -- an anonymous type created for a subtype indication. In that case it is
366 -- created in the procedure and attached to Related_Nod.
368 procedure Constrain_Array
369 (Def_Id : in out Entity_Id;
371 Related_Nod : Node_Id;
372 Related_Id : Entity_Id;
374 -- Apply a list of index constraints to an unconstrained array type. The
375 -- first parameter is the entity for the resulting subtype. A value of
376 -- Empty for Def_Id indicates that an implicit type must be created, but
377 -- creation is delayed (and must be done by this procedure) because other
378 -- subsidiary implicit types must be created first (which is why Def_Id
379 -- is an in/out parameter). The second parameter is a subtype indication
380 -- node for the constrained array to be created (e.g. something of the
381 -- form string (1 .. 10)). Related_Nod gives the place where this type
382 -- has to be inserted in the tree. The Related_Id and Suffix parameters
383 -- are used to build the associated Implicit type name.
385 procedure Constrain_Concurrent
386 (Def_Id : in out Entity_Id;
388 Related_Nod : Node_Id;
389 Related_Id : Entity_Id;
391 -- Apply list of discriminant constraints to an unconstrained concurrent
394 -- SI is the N_Subtype_Indication node containing the constraint and
395 -- the unconstrained type to constrain.
397 -- Def_Id is the entity for the resulting constrained subtype. A value
398 -- of Empty for Def_Id indicates that an implicit type must be created,
399 -- but creation is delayed (and must be done by this procedure) because
400 -- other subsidiary implicit types must be created first (which is why
401 -- Def_Id is an in/out parameter).
403 -- Related_Nod gives the place where this type has to be inserted
406 -- The last two arguments are used to create its external name if needed.
408 function Constrain_Corresponding_Record
409 (Prot_Subt : Entity_Id;
410 Corr_Rec : Entity_Id;
411 Related_Nod : Node_Id) return Entity_Id;
412 -- When constraining a protected type or task type with discriminants,
413 -- constrain the corresponding record with the same discriminant values.
415 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
416 -- Constrain a decimal fixed point type with a digits constraint and/or a
417 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
419 procedure Constrain_Discriminated_Type
422 Related_Nod : Node_Id;
423 For_Access : Boolean := False);
424 -- Process discriminant constraints of composite type. Verify that values
425 -- have been provided for all discriminants, that the original type is
426 -- unconstrained, and that the types of the supplied expressions match
427 -- the discriminant types. The first three parameters are like in routine
428 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
431 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
432 -- Constrain an enumeration type with a range constraint. This is identical
433 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
435 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
436 -- Constrain a floating point type with either a digits constraint
437 -- and/or a range constraint, building a E_Floating_Point_Subtype.
439 procedure Constrain_Index
442 Related_Nod : Node_Id;
443 Related_Id : Entity_Id;
446 -- Process an index constraint S in a constrained array declaration. The
447 -- constraint can be a subtype name, or a range with or without an explicit
448 -- subtype mark. The index is the corresponding index of the unconstrained
449 -- array. The Related_Id and Suffix parameters are used to build the
450 -- associated Implicit type name.
452 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
453 -- Build subtype of a signed or modular integer type
455 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
456 -- Constrain an ordinary fixed point type with a range constraint, and
457 -- build an E_Ordinary_Fixed_Point_Subtype entity.
459 procedure Copy_And_Swap (Priv, Full : Entity_Id);
460 -- Copy the Priv entity into the entity of its full declaration then swap
461 -- the two entities in such a manner that the former private type is now
462 -- seen as a full type.
464 procedure Decimal_Fixed_Point_Type_Declaration
467 -- Create a new decimal fixed point type, and apply the constraint to
468 -- obtain a subtype of this new type.
470 procedure Complete_Private_Subtype
473 Full_Base : Entity_Id;
474 Related_Nod : Node_Id);
475 -- Complete the implicit full view of a private subtype by setting the
476 -- appropriate semantic fields. If the full view of the parent is a record
477 -- type, build constrained components of subtype.
479 procedure Derive_Progenitor_Subprograms
480 (Parent_Type : Entity_Id;
481 Tagged_Type : Entity_Id);
482 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
483 -- operations of progenitors of Tagged_Type, and replace the subsidiary
484 -- subtypes with Tagged_Type, to build the specs of the inherited interface
485 -- primitives. The derived primitives are aliased to those of the
486 -- interface. This routine takes care also of transferring to the full view
487 -- subprograms associated with the partial view of Tagged_Type that cover
488 -- interface primitives.
490 procedure Derived_Standard_Character
492 Parent_Type : Entity_Id;
493 Derived_Type : Entity_Id);
494 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
495 -- derivations from types Standard.Character and Standard.Wide_Character.
497 procedure Derived_Type_Declaration
500 Is_Completion : Boolean);
501 -- Process a derived type declaration. Build_Derived_Type is invoked
502 -- to process the actual derived type definition. Parameters N and
503 -- Is_Completion have the same meaning as in Build_Derived_Type.
504 -- T is the N_Defining_Identifier for the entity defined in the
505 -- N_Full_Type_Declaration node N, that is T is the derived type.
507 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
508 -- Insert each literal in symbol table, as an overloadable identifier. Each
509 -- enumeration type is mapped into a sequence of integers, and each literal
510 -- is defined as a constant with integer value. If any of the literals are
511 -- character literals, the type is a character type, which means that
512 -- strings are legal aggregates for arrays of components of the type.
514 function Expand_To_Stored_Constraint
516 Constraint : Elist_Id) return Elist_Id;
517 -- Given a constraint (i.e. a list of expressions) on the discriminants of
518 -- Typ, expand it into a constraint on the stored discriminants and return
519 -- the new list of expressions constraining the stored discriminants.
521 function Find_Type_Of_Object
523 Related_Nod : Node_Id) return Entity_Id;
524 -- Get type entity for object referenced by Obj_Def, attaching the implicit
525 -- types generated to Related_Nod.
527 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
528 -- Create a new float and apply the constraint to obtain subtype of it
530 function Has_Range_Constraint (N : Node_Id) return Boolean;
531 -- Given an N_Subtype_Indication node N, return True if a range constraint
532 -- is present, either directly, or as part of a digits or delta constraint.
533 -- In addition, a digits constraint in the decimal case returns True, since
534 -- it establishes a default range if no explicit range is present.
536 function Inherit_Components
538 Parent_Base : Entity_Id;
539 Derived_Base : Entity_Id;
541 Inherit_Discr : Boolean;
542 Discs : Elist_Id) return Elist_Id;
543 -- Called from Build_Derived_Record_Type to inherit the components of
544 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
545 -- For more information on derived types and component inheritance please
546 -- consult the comment above the body of Build_Derived_Record_Type.
548 -- N is the original derived type declaration
550 -- Is_Tagged is set if we are dealing with tagged types
552 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
553 -- Parent_Base, otherwise no discriminants are inherited.
555 -- Discs gives the list of constraints that apply to Parent_Base in the
556 -- derived type declaration. If Discs is set to No_Elist, then we have
557 -- the following situation:
559 -- type Parent (D1..Dn : ..) is [tagged] record ...;
560 -- type Derived is new Parent [with ...];
562 -- which gets treated as
564 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
566 -- For untagged types the returned value is an association list. The list
567 -- starts from the association (Parent_Base => Derived_Base), and then it
568 -- contains a sequence of the associations of the form
570 -- (Old_Component => New_Component),
572 -- where Old_Component is the Entity_Id of a component in Parent_Base and
573 -- New_Component is the Entity_Id of the corresponding component in
574 -- Derived_Base. For untagged records, this association list is needed when
575 -- copying the record declaration for the derived base. In the tagged case
576 -- the value returned is irrelevant.
578 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
579 -- Propagate static and dynamic predicate flags from a parent to the
580 -- subtype in a subtype declaration with and without constraints.
582 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
583 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
584 -- Determine whether subprogram Subp is a procedure subject to pragma
585 -- Extensions_Visible with value False and has at least one controlling
586 -- parameter of mode OUT.
588 function Is_Valid_Constraint_Kind
590 Constraint_Kind : Node_Kind) return Boolean;
591 -- Returns True if it is legal to apply the given kind of constraint to the
592 -- given kind of type (index constraint to an array type, for example).
594 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
595 -- Create new modular type. Verify that modulus is in bounds
597 procedure New_Concatenation_Op (Typ : Entity_Id);
598 -- Create an abbreviated declaration for an operator in order to
599 -- materialize concatenation on array types.
601 procedure Ordinary_Fixed_Point_Type_Declaration
604 -- Create a new ordinary fixed point type, and apply the constraint to
605 -- obtain subtype of it.
607 procedure Prepare_Private_Subtype_Completion
609 Related_Nod : Node_Id);
610 -- Id is a subtype of some private type. Creates the full declaration
611 -- associated with Id whenever possible, i.e. when the full declaration
612 -- of the base type is already known. Records each subtype into
613 -- Private_Dependents of the base type.
615 procedure Process_Incomplete_Dependents
619 -- Process all entities that depend on an incomplete type. There include
620 -- subtypes, subprogram types that mention the incomplete type in their
621 -- profiles, and subprogram with access parameters that designate the
624 -- Inc_T is the defining identifier of an incomplete type declaration, its
625 -- Ekind is E_Incomplete_Type.
627 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
629 -- Full_T is N's defining identifier.
631 -- Subtypes of incomplete types with discriminants are completed when the
632 -- parent type is. This is simpler than private subtypes, because they can
633 -- only appear in the same scope, and there is no need to exchange views.
634 -- Similarly, access_to_subprogram types may have a parameter or a return
635 -- type that is an incomplete type, and that must be replaced with the
638 -- If the full type is tagged, subprogram with access parameters that
639 -- designated the incomplete may be primitive operations of the full type,
640 -- and have to be processed accordingly.
642 procedure Process_Real_Range_Specification (Def : Node_Id);
643 -- Given the type definition for a real type, this procedure processes and
644 -- checks the real range specification of this type definition if one is
645 -- present. If errors are found, error messages are posted, and the
646 -- Real_Range_Specification of Def is reset to Empty.
648 procedure Record_Type_Declaration
652 -- Process a record type declaration (for both untagged and tagged
653 -- records). Parameters T and N are exactly like in procedure
654 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
655 -- for this routine. If this is the completion of an incomplete type
656 -- declaration, Prev is the entity of the incomplete declaration, used for
657 -- cross-referencing. Otherwise Prev = T.
659 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
660 -- This routine is used to process the actual record type definition (both
661 -- for untagged and tagged records). Def is a record type definition node.
662 -- This procedure analyzes the components in this record type definition.
663 -- Prev_T is the entity for the enclosing record type. It is provided so
664 -- that its Has_Task flag can be set if any of the component have Has_Task
665 -- set. If the declaration is the completion of an incomplete type
666 -- declaration, Prev_T is the original incomplete type, whose full view is
669 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
670 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
671 -- build a copy of the declaration tree of the parent, and we create
672 -- independently the list of components for the derived type. Semantic
673 -- information uses the component entities, but record representation
674 -- clauses are validated on the declaration tree. This procedure replaces
675 -- discriminants and components in the declaration with those that have
676 -- been created by Inherit_Components.
678 procedure Set_Fixed_Range
683 -- Build a range node with the given bounds and set it as the Scalar_Range
684 -- of the given fixed-point type entity. Loc is the source location used
685 -- for the constructed range. See body for further details.
687 procedure Set_Scalar_Range_For_Subtype
691 -- This routine is used to set the scalar range field for a subtype given
692 -- Def_Id, the entity for the subtype, and R, the range expression for the
693 -- scalar range. Subt provides the parent subtype to be used to analyze,
694 -- resolve, and check the given range.
696 procedure Set_Default_SSO (T : Entity_Id);
697 -- T is the entity for an array or record being declared. This procedure
698 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
699 -- to the setting of Opt.Default_SSO.
701 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
702 -- Create a new signed integer entity, and apply the constraint to obtain
703 -- the required first named subtype of this type.
705 procedure Set_Stored_Constraint_From_Discriminant_Constraint
707 -- E is some record type. This routine computes E's Stored_Constraint
708 -- from its Discriminant_Constraint.
710 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
711 -- Check that an entity in a list of progenitors is an interface,
712 -- emit error otherwise.
714 -----------------------
715 -- Access_Definition --
716 -----------------------
718 function Access_Definition
719 (Related_Nod : Node_Id;
720 N : Node_Id) return Entity_Id
722 Anon_Type : Entity_Id;
723 Anon_Scope : Entity_Id;
724 Desig_Type : Entity_Id;
725 Enclosing_Prot_Type : Entity_Id := Empty;
728 Check_SPARK_05_Restriction ("access type is not allowed", N);
730 if Is_Entry (Current_Scope)
731 and then Is_Task_Type (Etype (Scope (Current_Scope)))
733 Error_Msg_N ("task entries cannot have access parameters", N);
737 -- Ada 2005: For an object declaration the corresponding anonymous
738 -- type is declared in the current scope.
740 -- If the access definition is the return type of another access to
741 -- function, scope is the current one, because it is the one of the
742 -- current type declaration, except for the pathological case below.
744 if Nkind_In (Related_Nod, N_Object_Declaration,
745 N_Access_Function_Definition)
747 Anon_Scope := Current_Scope;
749 -- A pathological case: function returning access functions that
750 -- return access functions, etc. Each anonymous access type created
751 -- is in the enclosing scope of the outermost function.
758 while Nkind_In (Par, N_Access_Function_Definition,
764 if Nkind (Par) = N_Function_Specification then
765 Anon_Scope := Scope (Defining_Entity (Par));
769 -- For the anonymous function result case, retrieve the scope of the
770 -- function specification's associated entity rather than using the
771 -- current scope. The current scope will be the function itself if the
772 -- formal part is currently being analyzed, but will be the parent scope
773 -- in the case of a parameterless function, and we always want to use
774 -- the function's parent scope. Finally, if the function is a child
775 -- unit, we must traverse the tree to retrieve the proper entity.
777 elsif Nkind (Related_Nod) = N_Function_Specification
778 and then Nkind (Parent (N)) /= N_Parameter_Specification
780 -- If the current scope is a protected type, the anonymous access
781 -- is associated with one of the protected operations, and must
782 -- be available in the scope that encloses the protected declaration.
783 -- Otherwise the type is in the scope enclosing the subprogram.
785 -- If the function has formals, The return type of a subprogram
786 -- declaration is analyzed in the scope of the subprogram (see
787 -- Process_Formals) and thus the protected type, if present, is
788 -- the scope of the current function scope.
790 if Ekind (Current_Scope) = E_Protected_Type then
791 Enclosing_Prot_Type := Current_Scope;
793 elsif Ekind (Current_Scope) = E_Function
794 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
796 Enclosing_Prot_Type := Scope (Current_Scope);
799 if Present (Enclosing_Prot_Type) then
800 Anon_Scope := Scope (Enclosing_Prot_Type);
803 Anon_Scope := Scope (Defining_Entity (Related_Nod));
806 -- For an access type definition, if the current scope is a child
807 -- unit it is the scope of the type.
809 elsif Is_Compilation_Unit (Current_Scope) then
810 Anon_Scope := Current_Scope;
812 -- For access formals, access components, and access discriminants, the
813 -- scope is that of the enclosing declaration,
816 Anon_Scope := Scope (Current_Scope);
821 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
824 and then Ada_Version >= Ada_2005
826 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
829 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
830 -- the corresponding semantic routine
832 if Present (Access_To_Subprogram_Definition (N)) then
834 -- Compiler runtime units are compiled in Ada 2005 mode when building
835 -- the runtime library but must also be compilable in Ada 95 mode
836 -- (when bootstrapping the compiler).
838 Check_Compiler_Unit ("anonymous access to subprogram", N);
840 Access_Subprogram_Declaration
841 (T_Name => Anon_Type,
842 T_Def => Access_To_Subprogram_Definition (N));
844 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
846 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
848 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
851 Set_Can_Use_Internal_Rep
852 (Anon_Type, not Always_Compatible_Rep_On_Target);
854 -- If the anonymous access is associated with a protected operation,
855 -- create a reference to it after the enclosing protected definition
856 -- because the itype will be used in the subsequent bodies.
858 -- If the anonymous access itself is protected, a full type
859 -- declaratiton will be created for it, so that the equivalent
860 -- record type can be constructed. For further details, see
861 -- Replace_Anonymous_Access_To_Protected-Subprogram.
863 if Ekind (Current_Scope) = E_Protected_Type
864 and then not Protected_Present (Access_To_Subprogram_Definition (N))
866 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
872 Find_Type (Subtype_Mark (N));
873 Desig_Type := Entity (Subtype_Mark (N));
875 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
876 Set_Etype (Anon_Type, Anon_Type);
878 -- Make sure the anonymous access type has size and alignment fields
879 -- set, as required by gigi. This is necessary in the case of the
880 -- Task_Body_Procedure.
882 if not Has_Private_Component (Desig_Type) then
883 Layout_Type (Anon_Type);
886 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
887 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
888 -- the null value is allowed. In Ada 95 the null value is never allowed.
890 if Ada_Version >= Ada_2005 then
891 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
893 Set_Can_Never_Be_Null (Anon_Type, True);
896 -- The anonymous access type is as public as the discriminated type or
897 -- subprogram that defines it. It is imported (for back-end purposes)
898 -- if the designated type is.
900 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
902 -- Ada 2005 (AI-231): Propagate the access-constant attribute
904 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
906 -- The context is either a subprogram declaration, object declaration,
907 -- or an access discriminant, in a private or a full type declaration.
908 -- In the case of a subprogram, if the designated type is incomplete,
909 -- the operation will be a primitive operation of the full type, to be
910 -- updated subsequently. If the type is imported through a limited_with
911 -- clause, the subprogram is not a primitive operation of the type
912 -- (which is declared elsewhere in some other scope).
914 if Ekind (Desig_Type) = E_Incomplete_Type
915 and then not From_Limited_With (Desig_Type)
916 and then Is_Overloadable (Current_Scope)
918 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
919 Set_Has_Delayed_Freeze (Current_Scope);
922 -- Ada 2005: If the designated type is an interface that may contain
923 -- tasks, create a Master entity for the declaration. This must be done
924 -- before expansion of the full declaration, because the declaration may
925 -- include an expression that is an allocator, whose expansion needs the
926 -- proper Master for the created tasks.
928 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
930 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
932 Build_Class_Wide_Master (Anon_Type);
934 -- Similarly, if the type is an anonymous access that designates
935 -- tasks, create a master entity for it in the current context.
937 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
939 Build_Master_Entity (Defining_Identifier (Related_Nod));
940 Build_Master_Renaming (Anon_Type);
944 -- For a private component of a protected type, it is imperative that
945 -- the back-end elaborate the type immediately after the protected
946 -- declaration, because this type will be used in the declarations
947 -- created for the component within each protected body, so we must
948 -- create an itype reference for it now.
950 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
951 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
953 -- Similarly, if the access definition is the return result of a
954 -- function, create an itype reference for it because it will be used
955 -- within the function body. For a regular function that is not a
956 -- compilation unit, insert reference after the declaration. For a
957 -- protected operation, insert it after the enclosing protected type
958 -- declaration. In either case, do not create a reference for a type
959 -- obtained through a limited_with clause, because this would introduce
960 -- semantic dependencies.
962 -- Similarly, do not create a reference if the designated type is a
963 -- generic formal, because no use of it will reach the backend.
965 elsif Nkind (Related_Nod) = N_Function_Specification
966 and then not From_Limited_With (Desig_Type)
967 and then not Is_Generic_Type (Desig_Type)
969 if Present (Enclosing_Prot_Type) then
970 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
972 elsif Is_List_Member (Parent (Related_Nod))
973 and then Nkind (Parent (N)) /= N_Parameter_Specification
975 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
978 -- Finally, create an itype reference for an object declaration of an
979 -- anonymous access type. This is strictly necessary only for deferred
980 -- constants, but in any case will avoid out-of-scope problems in the
983 elsif Nkind (Related_Nod) = N_Object_Declaration then
984 Build_Itype_Reference (Anon_Type, Related_Nod);
988 end Access_Definition;
990 -----------------------------------
991 -- Access_Subprogram_Declaration --
992 -----------------------------------
994 procedure Access_Subprogram_Declaration
998 procedure Check_For_Premature_Usage (Def : Node_Id);
999 -- Check that type T_Name is not used, directly or recursively, as a
1000 -- parameter or a return type in Def. Def is either a subtype, an
1001 -- access_definition, or an access_to_subprogram_definition.
1003 -------------------------------
1004 -- Check_For_Premature_Usage --
1005 -------------------------------
1007 procedure Check_For_Premature_Usage (Def : Node_Id) is
1011 -- Check for a subtype mark
1013 if Nkind (Def) in N_Has_Etype then
1014 if Etype (Def) = T_Name then
1016 ("type& cannot be used before end of its declaration", Def);
1019 -- If this is not a subtype, then this is an access_definition
1021 elsif Nkind (Def) = N_Access_Definition then
1022 if Present (Access_To_Subprogram_Definition (Def)) then
1023 Check_For_Premature_Usage
1024 (Access_To_Subprogram_Definition (Def));
1026 Check_For_Premature_Usage (Subtype_Mark (Def));
1029 -- The only cases left are N_Access_Function_Definition and
1030 -- N_Access_Procedure_Definition.
1033 if Present (Parameter_Specifications (Def)) then
1034 Param := First (Parameter_Specifications (Def));
1035 while Present (Param) loop
1036 Check_For_Premature_Usage (Parameter_Type (Param));
1037 Param := Next (Param);
1041 if Nkind (Def) = N_Access_Function_Definition then
1042 Check_For_Premature_Usage (Result_Definition (Def));
1045 end Check_For_Premature_Usage;
1049 Formals : constant List_Id := Parameter_Specifications (T_Def);
1052 Desig_Type : constant Entity_Id :=
1053 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1055 -- Start of processing for Access_Subprogram_Declaration
1058 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1060 -- Associate the Itype node with the inner full-type declaration or
1061 -- subprogram spec or entry body. This is required to handle nested
1062 -- anonymous declarations. For example:
1065 -- (X : access procedure
1066 -- (Y : access procedure
1069 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1070 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1071 N_Private_Type_Declaration,
1072 N_Private_Extension_Declaration,
1073 N_Procedure_Specification,
1074 N_Function_Specification,
1078 Nkind_In (D_Ityp, N_Object_Declaration,
1079 N_Object_Renaming_Declaration,
1080 N_Formal_Object_Declaration,
1081 N_Formal_Type_Declaration,
1082 N_Task_Type_Declaration,
1083 N_Protected_Type_Declaration))
1085 D_Ityp := Parent (D_Ityp);
1086 pragma Assert (D_Ityp /= Empty);
1089 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1091 if Nkind_In (D_Ityp, N_Procedure_Specification,
1092 N_Function_Specification)
1094 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1096 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1097 N_Object_Declaration,
1098 N_Object_Renaming_Declaration,
1099 N_Formal_Type_Declaration)
1101 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1104 if Nkind (T_Def) = N_Access_Function_Definition then
1105 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1107 Acc : constant Node_Id := Result_Definition (T_Def);
1110 if Present (Access_To_Subprogram_Definition (Acc))
1112 Protected_Present (Access_To_Subprogram_Definition (Acc))
1116 Replace_Anonymous_Access_To_Protected_Subprogram
1122 Access_Definition (T_Def, Result_Definition (T_Def)));
1127 Analyze (Result_Definition (T_Def));
1130 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1133 -- If a null exclusion is imposed on the result type, then
1134 -- create a null-excluding itype (an access subtype) and use
1135 -- it as the function's Etype.
1137 if Is_Access_Type (Typ)
1138 and then Null_Exclusion_In_Return_Present (T_Def)
1140 Set_Etype (Desig_Type,
1141 Create_Null_Excluding_Itype
1143 Related_Nod => T_Def,
1144 Scope_Id => Current_Scope));
1147 if From_Limited_With (Typ) then
1149 -- AI05-151: Incomplete types are allowed in all basic
1150 -- declarations, including access to subprograms.
1152 if Ada_Version >= Ada_2012 then
1157 ("illegal use of incomplete type&",
1158 Result_Definition (T_Def), Typ);
1161 elsif Ekind (Current_Scope) = E_Package
1162 and then In_Private_Part (Current_Scope)
1164 if Ekind (Typ) = E_Incomplete_Type then
1165 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1167 elsif Is_Class_Wide_Type (Typ)
1168 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1171 (Desig_Type, Private_Dependents (Etype (Typ)));
1175 Set_Etype (Desig_Type, Typ);
1180 if not (Is_Type (Etype (Desig_Type))) then
1182 ("expect type in function specification",
1183 Result_Definition (T_Def));
1187 Set_Etype (Desig_Type, Standard_Void_Type);
1190 if Present (Formals) then
1191 Push_Scope (Desig_Type);
1193 -- Some special tests here. These special tests can be removed
1194 -- if and when Itypes always have proper parent pointers to their
1197 -- Special test 1) Link defining_identifier of formals. Required by
1198 -- First_Formal to provide its functionality.
1204 F := First (Formals);
1206 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1207 -- when it is part of an unconstrained type and subtype expansion
1208 -- is disabled. To avoid back-end problems with shared profiles,
1209 -- use previous subprogram type as the designated type, and then
1210 -- remove scope added above.
1212 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1214 Set_Etype (T_Name, T_Name);
1215 Init_Size_Align (T_Name);
1216 Set_Directly_Designated_Type (T_Name,
1217 Scope (Defining_Identifier (F)));
1222 while Present (F) loop
1223 if No (Parent (Defining_Identifier (F))) then
1224 Set_Parent (Defining_Identifier (F), F);
1231 Process_Formals (Formals, Parent (T_Def));
1233 -- Special test 2) End_Scope requires that the parent pointer be set
1234 -- to something reasonable, but Itypes don't have parent pointers. So
1235 -- we set it and then unset it ???
1237 Set_Parent (Desig_Type, T_Name);
1239 Set_Parent (Desig_Type, Empty);
1242 -- Check for premature usage of the type being defined
1244 Check_For_Premature_Usage (T_Def);
1246 -- The return type and/or any parameter type may be incomplete. Mark the
1247 -- subprogram_type as depending on the incomplete type, so that it can
1248 -- be updated when the full type declaration is seen. This only applies
1249 -- to incomplete types declared in some enclosing scope, not to limited
1250 -- views from other packages.
1252 -- Prior to Ada 2012, access to functions can only have in_parameters.
1254 if Present (Formals) then
1255 Formal := First_Formal (Desig_Type);
1256 while Present (Formal) loop
1257 if Ekind (Formal) /= E_In_Parameter
1258 and then Nkind (T_Def) = N_Access_Function_Definition
1259 and then Ada_Version < Ada_2012
1261 Error_Msg_N ("functions can only have IN parameters", Formal);
1264 if Ekind (Etype (Formal)) = E_Incomplete_Type
1265 and then In_Open_Scopes (Scope (Etype (Formal)))
1267 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1268 Set_Has_Delayed_Freeze (Desig_Type);
1271 Next_Formal (Formal);
1275 -- Check whether an indirect call without actuals may be possible. This
1276 -- is used when resolving calls whose result is then indexed.
1278 May_Need_Actuals (Desig_Type);
1280 -- If the return type is incomplete, this is legal as long as the type
1281 -- is declared in the current scope and will be completed in it (rather
1282 -- than being part of limited view).
1284 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1285 and then not Has_Delayed_Freeze (Desig_Type)
1286 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1288 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1289 Set_Has_Delayed_Freeze (Desig_Type);
1292 Check_Delayed_Subprogram (Desig_Type);
1294 if Protected_Present (T_Def) then
1295 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1296 Set_Convention (Desig_Type, Convention_Protected);
1298 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1301 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1303 Set_Etype (T_Name, T_Name);
1304 Init_Size_Align (T_Name);
1305 Set_Directly_Designated_Type (T_Name, Desig_Type);
1307 Generate_Reference_To_Formals (T_Name);
1309 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1311 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1313 Check_Restriction (No_Access_Subprograms, T_Def);
1314 end Access_Subprogram_Declaration;
1316 ----------------------------
1317 -- Access_Type_Declaration --
1318 ----------------------------
1320 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1321 P : constant Node_Id := Parent (Def);
1322 S : constant Node_Id := Subtype_Indication (Def);
1324 Full_Desig : Entity_Id;
1327 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1329 -- Check for permissible use of incomplete type
1331 if Nkind (S) /= N_Subtype_Indication then
1334 if Present (Entity (S))
1335 and then Ekind (Root_Type (Entity (S))) = E_Incomplete_Type
1337 Set_Directly_Designated_Type (T, Entity (S));
1339 -- If the designated type is a limited view, we cannot tell if
1340 -- the full view contains tasks, and there is no way to handle
1341 -- that full view in a client. We create a master entity for the
1342 -- scope, which will be used when a client determines that one
1345 if From_Limited_With (Entity (S))
1346 and then not Is_Class_Wide_Type (Entity (S))
1348 Set_Ekind (T, E_Access_Type);
1349 Build_Master_Entity (T);
1350 Build_Master_Renaming (T);
1354 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1357 -- If the access definition is of the form: ACCESS NOT NULL ..
1358 -- the subtype indication must be of an access type. Create
1359 -- a null-excluding subtype of it.
1361 if Null_Excluding_Subtype (Def) then
1362 if not Is_Access_Type (Entity (S)) then
1363 Error_Msg_N ("null exclusion must apply to access type", Def);
1367 Loc : constant Source_Ptr := Sloc (S);
1369 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1373 Make_Subtype_Declaration (Loc,
1374 Defining_Identifier => Nam,
1375 Subtype_Indication =>
1376 New_Occurrence_Of (Entity (S), Loc));
1377 Set_Null_Exclusion_Present (Decl);
1378 Insert_Before (Parent (Def), Decl);
1380 Set_Entity (S, Nam);
1386 Set_Directly_Designated_Type (T,
1387 Process_Subtype (S, P, T, 'P'));
1390 if All_Present (Def) or Constant_Present (Def) then
1391 Set_Ekind (T, E_General_Access_Type);
1393 Set_Ekind (T, E_Access_Type);
1396 Full_Desig := Designated_Type (T);
1398 if Base_Type (Full_Desig) = T then
1399 Error_Msg_N ("access type cannot designate itself", S);
1401 -- In Ada 2005, the type may have a limited view through some unit in
1402 -- its own context, allowing the following circularity that cannot be
1403 -- detected earlier.
1405 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1408 ("access type cannot designate its own class-wide type", S);
1410 -- Clean up indication of tagged status to prevent cascaded errors
1412 Set_Is_Tagged_Type (T, False);
1417 -- If the type has appeared already in a with_type clause, it is frozen
1418 -- and the pointer size is already set. Else, initialize.
1420 if not From_Limited_With (T) then
1421 Init_Size_Align (T);
1424 -- Note that Has_Task is always false, since the access type itself
1425 -- is not a task type. See Einfo for more description on this point.
1426 -- Exactly the same consideration applies to Has_Controlled_Component
1427 -- and to Has_Protected.
1429 Set_Has_Task (T, False);
1430 Set_Has_Protected (T, False);
1431 Set_Has_Timing_Event (T, False);
1432 Set_Has_Controlled_Component (T, False);
1434 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1435 -- problems where an incomplete view of this entity has been previously
1436 -- established by a limited with and an overlaid version of this field
1437 -- (Stored_Constraint) was initialized for the incomplete view.
1439 -- This reset is performed in most cases except where the access type
1440 -- has been created for the purposes of allocating or deallocating a
1441 -- build-in-place object. Such access types have explicitly set pools
1442 -- and finalization masters.
1444 if No (Associated_Storage_Pool (T)) then
1445 Set_Finalization_Master (T, Empty);
1448 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1451 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1452 Set_Is_Access_Constant (T, Constant_Present (Def));
1453 end Access_Type_Declaration;
1455 ----------------------------------
1456 -- Add_Interface_Tag_Components --
1457 ----------------------------------
1459 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1460 Loc : constant Source_Ptr := Sloc (N);
1464 procedure Add_Tag (Iface : Entity_Id);
1465 -- Add tag for one of the progenitor interfaces
1471 procedure Add_Tag (Iface : Entity_Id) is
1478 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1480 -- This is a reasonable place to propagate predicates
1482 if Has_Predicates (Iface) then
1483 Set_Has_Predicates (Typ);
1487 Make_Component_Definition (Loc,
1488 Aliased_Present => True,
1489 Subtype_Indication =>
1490 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1492 Tag := Make_Temporary (Loc, 'V');
1495 Make_Component_Declaration (Loc,
1496 Defining_Identifier => Tag,
1497 Component_Definition => Def);
1499 Analyze_Component_Declaration (Decl);
1501 Set_Analyzed (Decl);
1502 Set_Ekind (Tag, E_Component);
1504 Set_Is_Aliased (Tag);
1505 Set_Related_Type (Tag, Iface);
1506 Init_Component_Location (Tag);
1508 pragma Assert (Is_Frozen (Iface));
1510 Set_DT_Entry_Count (Tag,
1511 DT_Entry_Count (First_Entity (Iface)));
1513 if No (Last_Tag) then
1516 Insert_After (Last_Tag, Decl);
1521 -- If the ancestor has discriminants we need to give special support
1522 -- to store the offset_to_top value of the secondary dispatch tables.
1523 -- For this purpose we add a supplementary component just after the
1524 -- field that contains the tag associated with each secondary DT.
1526 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1528 Make_Component_Definition (Loc,
1529 Subtype_Indication =>
1530 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1532 Offset := Make_Temporary (Loc, 'V');
1535 Make_Component_Declaration (Loc,
1536 Defining_Identifier => Offset,
1537 Component_Definition => Def);
1539 Analyze_Component_Declaration (Decl);
1541 Set_Analyzed (Decl);
1542 Set_Ekind (Offset, E_Component);
1543 Set_Is_Aliased (Offset);
1544 Set_Related_Type (Offset, Iface);
1545 Init_Component_Location (Offset);
1546 Insert_After (Last_Tag, Decl);
1557 -- Start of processing for Add_Interface_Tag_Components
1560 if not RTE_Available (RE_Interface_Tag) then
1562 ("(Ada 2005) interface types not supported by this run-time!",
1567 if Ekind (Typ) /= E_Record_Type
1568 or else (Is_Concurrent_Record_Type (Typ)
1569 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1570 or else (not Is_Concurrent_Record_Type (Typ)
1571 and then No (Interfaces (Typ))
1572 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1577 -- Find the current last tag
1579 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1580 Ext := Record_Extension_Part (Type_Definition (N));
1582 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1583 Ext := Type_Definition (N);
1588 if not (Present (Component_List (Ext))) then
1589 Set_Null_Present (Ext, False);
1591 Set_Component_List (Ext,
1592 Make_Component_List (Loc,
1593 Component_Items => L,
1594 Null_Present => False));
1596 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1597 L := Component_Items
1599 (Record_Extension_Part
1600 (Type_Definition (N))));
1602 L := Component_Items
1604 (Type_Definition (N)));
1607 -- Find the last tag component
1610 while Present (Comp) loop
1611 if Nkind (Comp) = N_Component_Declaration
1612 and then Is_Tag (Defining_Identifier (Comp))
1621 -- At this point L references the list of components and Last_Tag
1622 -- references the current last tag (if any). Now we add the tag
1623 -- corresponding with all the interfaces that are not implemented
1626 if Present (Interfaces (Typ)) then
1627 Elmt := First_Elmt (Interfaces (Typ));
1628 while Present (Elmt) loop
1629 Add_Tag (Node (Elmt));
1633 end Add_Interface_Tag_Components;
1635 -------------------------------------
1636 -- Add_Internal_Interface_Entities --
1637 -------------------------------------
1639 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1642 Iface_Elmt : Elmt_Id;
1643 Iface_Prim : Entity_Id;
1644 Ifaces_List : Elist_Id;
1645 New_Subp : Entity_Id := Empty;
1647 Restore_Scope : Boolean := False;
1650 pragma Assert (Ada_Version >= Ada_2005
1651 and then Is_Record_Type (Tagged_Type)
1652 and then Is_Tagged_Type (Tagged_Type)
1653 and then Has_Interfaces (Tagged_Type)
1654 and then not Is_Interface (Tagged_Type));
1656 -- Ensure that the internal entities are added to the scope of the type
1658 if Scope (Tagged_Type) /= Current_Scope then
1659 Push_Scope (Scope (Tagged_Type));
1660 Restore_Scope := True;
1663 Collect_Interfaces (Tagged_Type, Ifaces_List);
1665 Iface_Elmt := First_Elmt (Ifaces_List);
1666 while Present (Iface_Elmt) loop
1667 Iface := Node (Iface_Elmt);
1669 -- Originally we excluded here from this processing interfaces that
1670 -- are parents of Tagged_Type because their primitives are located
1671 -- in the primary dispatch table (and hence no auxiliary internal
1672 -- entities are required to handle secondary dispatch tables in such
1673 -- case). However, these auxiliary entities are also required to
1674 -- handle derivations of interfaces in formals of generics (see
1675 -- Derive_Subprograms).
1677 Elmt := First_Elmt (Primitive_Operations (Iface));
1678 while Present (Elmt) loop
1679 Iface_Prim := Node (Elmt);
1681 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1683 Find_Primitive_Covering_Interface
1684 (Tagged_Type => Tagged_Type,
1685 Iface_Prim => Iface_Prim);
1687 if No (Prim) and then Serious_Errors_Detected > 0 then
1691 pragma Assert (Present (Prim));
1693 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1694 -- differs from the name of the interface primitive then it is
1695 -- a private primitive inherited from a parent type. In such
1696 -- case, given that Tagged_Type covers the interface, the
1697 -- inherited private primitive becomes visible. For such
1698 -- purpose we add a new entity that renames the inherited
1699 -- private primitive.
1701 if Chars (Prim) /= Chars (Iface_Prim) then
1702 pragma Assert (Has_Suffix (Prim, 'P'));
1704 (New_Subp => New_Subp,
1705 Parent_Subp => Iface_Prim,
1706 Derived_Type => Tagged_Type,
1707 Parent_Type => Iface);
1708 Set_Alias (New_Subp, Prim);
1709 Set_Is_Abstract_Subprogram
1710 (New_Subp, Is_Abstract_Subprogram (Prim));
1714 (New_Subp => New_Subp,
1715 Parent_Subp => Iface_Prim,
1716 Derived_Type => Tagged_Type,
1717 Parent_Type => Iface);
1722 if Is_Inherited_Operation (Prim)
1723 and then Present (Alias (Prim))
1725 Anc := Alias (Prim);
1727 Anc := Overridden_Operation (Prim);
1730 -- Apply legality checks in RM 6.1.1 (10-13) concerning
1731 -- nonconforming preconditions in both an ancestor and
1732 -- a progenitor operation.
1735 and then Has_Non_Trivial_Precondition (Anc)
1736 and then Has_Non_Trivial_Precondition (Iface_Prim)
1738 if Is_Abstract_Subprogram (Prim)
1740 (Ekind (Prim) = E_Procedure
1741 and then Nkind (Parent (Prim)) =
1742 N_Procedure_Specification
1743 and then Null_Present (Parent (Prim)))
1747 -- The inherited operation must be overridden
1749 elsif not Comes_From_Source (Prim) then
1751 ("&inherits non-conforming preconditions and must "
1752 & "be overridden (RM 6.1.1 (10-16)",
1753 Parent (Tagged_Type), Prim);
1758 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1759 -- associated with interface types. These entities are
1760 -- only registered in the list of primitives of its
1761 -- corresponding tagged type because they are only used
1762 -- to fill the contents of the secondary dispatch tables.
1763 -- Therefore they are removed from the homonym chains.
1765 Set_Is_Hidden (New_Subp);
1766 Set_Is_Internal (New_Subp);
1767 Set_Alias (New_Subp, Prim);
1768 Set_Is_Abstract_Subprogram
1769 (New_Subp, Is_Abstract_Subprogram (Prim));
1770 Set_Interface_Alias (New_Subp, Iface_Prim);
1772 -- If the returned type is an interface then propagate it to
1773 -- the returned type. Needed by the thunk to generate the code
1774 -- which displaces "this" to reference the corresponding
1775 -- secondary dispatch table in the returned object.
1777 if Is_Interface (Etype (Iface_Prim)) then
1778 Set_Etype (New_Subp, Etype (Iface_Prim));
1781 -- Internal entities associated with interface types are only
1782 -- registered in the list of primitives of the tagged type.
1783 -- They are only used to fill the contents of the secondary
1784 -- dispatch tables. Therefore they are not needed in the
1787 Remove_Homonym (New_Subp);
1789 -- Hidden entities associated with interfaces must have set
1790 -- the Has_Delay_Freeze attribute to ensure that, in case
1791 -- of locally defined tagged types (or compiling with static
1792 -- dispatch tables generation disabled) the corresponding
1793 -- entry of the secondary dispatch table is filled when such
1794 -- an entity is frozen. This is an expansion activity that must
1795 -- be suppressed for ASIS because it leads to gigi elaboration
1796 -- issues in annotate mode.
1798 if not ASIS_Mode then
1799 Set_Has_Delayed_Freeze (New_Subp);
1807 Next_Elmt (Iface_Elmt);
1810 if Restore_Scope then
1813 end Add_Internal_Interface_Entities;
1815 -----------------------------------
1816 -- Analyze_Component_Declaration --
1817 -----------------------------------
1819 procedure Analyze_Component_Declaration (N : Node_Id) is
1820 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1821 Id : constant Entity_Id := Defining_Identifier (N);
1822 E : constant Node_Id := Expression (N);
1823 Typ : constant Node_Id :=
1824 Subtype_Indication (Component_Definition (N));
1828 function Contains_POC (Constr : Node_Id) return Boolean;
1829 -- Determines whether a constraint uses the discriminant of a record
1830 -- type thus becoming a per-object constraint (POC).
1832 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1833 -- Typ is the type of the current component, check whether this type is
1834 -- a limited type. Used to validate declaration against that of
1835 -- enclosing record.
1841 function Contains_POC (Constr : Node_Id) return Boolean is
1843 -- Prevent cascaded errors
1845 if Error_Posted (Constr) then
1849 case Nkind (Constr) is
1850 when N_Attribute_Reference =>
1851 return Attribute_Name (Constr) = Name_Access
1852 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1854 when N_Discriminant_Association =>
1855 return Denotes_Discriminant (Expression (Constr));
1857 when N_Identifier =>
1858 return Denotes_Discriminant (Constr);
1860 when N_Index_Or_Discriminant_Constraint =>
1865 IDC := First (Constraints (Constr));
1866 while Present (IDC) loop
1868 -- One per-object constraint is sufficient
1870 if Contains_POC (IDC) then
1881 return Denotes_Discriminant (Low_Bound (Constr))
1883 Denotes_Discriminant (High_Bound (Constr));
1885 when N_Range_Constraint =>
1886 return Denotes_Discriminant (Range_Expression (Constr));
1893 ----------------------
1894 -- Is_Known_Limited --
1895 ----------------------
1897 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1898 P : constant Entity_Id := Etype (Typ);
1899 R : constant Entity_Id := Root_Type (Typ);
1902 if Is_Limited_Record (Typ) then
1905 -- If the root type is limited (and not a limited interface)
1906 -- so is the current type
1908 elsif Is_Limited_Record (R)
1909 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1913 -- Else the type may have a limited interface progenitor, but a
1914 -- limited record parent.
1916 elsif R /= P and then Is_Limited_Record (P) then
1922 end Is_Known_Limited;
1924 -- Start of processing for Analyze_Component_Declaration
1927 Generate_Definition (Id);
1930 if Present (Typ) then
1931 T := Find_Type_Of_Object
1932 (Subtype_Indication (Component_Definition (N)), N);
1934 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1935 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1938 -- Ada 2005 (AI-230): Access Definition case
1941 pragma Assert (Present
1942 (Access_Definition (Component_Definition (N))));
1944 T := Access_Definition
1946 N => Access_Definition (Component_Definition (N)));
1947 Set_Is_Local_Anonymous_Access (T);
1949 -- Ada 2005 (AI-254)
1951 if Present (Access_To_Subprogram_Definition
1952 (Access_Definition (Component_Definition (N))))
1953 and then Protected_Present (Access_To_Subprogram_Definition
1955 (Component_Definition (N))))
1957 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1961 -- If the subtype is a constrained subtype of the enclosing record,
1962 -- (which must have a partial view) the back-end does not properly
1963 -- handle the recursion. Rewrite the component declaration with an
1964 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1965 -- the tree directly because side effects have already been removed from
1966 -- discriminant constraints.
1968 if Ekind (T) = E_Access_Subtype
1969 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1970 and then Comes_From_Source (T)
1971 and then Nkind (Parent (T)) = N_Subtype_Declaration
1972 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1975 (Subtype_Indication (Component_Definition (N)),
1976 New_Copy_Tree (Subtype_Indication (Parent (T))));
1977 T := Find_Type_Of_Object
1978 (Subtype_Indication (Component_Definition (N)), N);
1981 -- If the component declaration includes a default expression, then we
1982 -- check that the component is not of a limited type (RM 3.7(5)),
1983 -- and do the special preanalysis of the expression (see section on
1984 -- "Handling of Default and Per-Object Expressions" in the spec of
1988 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1989 Preanalyze_Default_Expression (E, T);
1990 Check_Initialization (T, E);
1992 if Ada_Version >= Ada_2005
1993 and then Ekind (T) = E_Anonymous_Access_Type
1994 and then Etype (E) /= Any_Type
1996 -- Check RM 3.9.2(9): "if the expected type for an expression is
1997 -- an anonymous access-to-specific tagged type, then the object
1998 -- designated by the expression shall not be dynamically tagged
1999 -- unless it is a controlling operand in a call on a dispatching
2002 if Is_Tagged_Type (Directly_Designated_Type (T))
2004 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
2006 Ekind (Directly_Designated_Type (Etype (E))) =
2010 ("access to specific tagged type required (RM 3.9.2(9))", E);
2013 -- (Ada 2005: AI-230): Accessibility check for anonymous
2016 if Type_Access_Level (Etype (E)) >
2017 Deepest_Type_Access_Level (T)
2020 ("expression has deeper access level than component " &
2021 "(RM 3.10.2 (12.2))", E);
2024 -- The initialization expression is a reference to an access
2025 -- discriminant. The type of the discriminant is always deeper
2026 -- than any access type.
2028 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2029 and then Is_Entity_Name (E)
2030 and then Ekind (Entity (E)) = E_In_Parameter
2031 and then Present (Discriminal_Link (Entity (E)))
2034 ("discriminant has deeper accessibility level than target",
2040 -- The parent type may be a private view with unknown discriminants,
2041 -- and thus unconstrained. Regular components must be constrained.
2043 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2044 if Is_Class_Wide_Type (T) then
2046 ("class-wide subtype with unknown discriminants" &
2047 " in component declaration",
2048 Subtype_Indication (Component_Definition (N)));
2051 ("unconstrained subtype in component declaration",
2052 Subtype_Indication (Component_Definition (N)));
2055 -- Components cannot be abstract, except for the special case of
2056 -- the _Parent field (case of extending an abstract tagged type)
2058 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2059 Error_Msg_N ("type of a component cannot be abstract", N);
2063 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2065 -- The component declaration may have a per-object constraint, set
2066 -- the appropriate flag in the defining identifier of the subtype.
2068 if Present (Subtype_Indication (Component_Definition (N))) then
2070 Sindic : constant Node_Id :=
2071 Subtype_Indication (Component_Definition (N));
2073 if Nkind (Sindic) = N_Subtype_Indication
2074 and then Present (Constraint (Sindic))
2075 and then Contains_POC (Constraint (Sindic))
2077 Set_Has_Per_Object_Constraint (Id);
2082 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2083 -- out some static checks.
2085 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2086 Null_Exclusion_Static_Checks (N);
2089 -- If this component is private (or depends on a private type), flag the
2090 -- record type to indicate that some operations are not available.
2092 P := Private_Component (T);
2096 -- Check for circular definitions
2098 if P = Any_Type then
2099 Set_Etype (Id, Any_Type);
2101 -- There is a gap in the visibility of operations only if the
2102 -- component type is not defined in the scope of the record type.
2104 elsif Scope (P) = Scope (Current_Scope) then
2107 elsif Is_Limited_Type (P) then
2108 Set_Is_Limited_Composite (Current_Scope);
2111 Set_Is_Private_Composite (Current_Scope);
2116 and then Is_Limited_Type (T)
2117 and then Chars (Id) /= Name_uParent
2118 and then Is_Tagged_Type (Current_Scope)
2120 if Is_Derived_Type (Current_Scope)
2121 and then not Is_Known_Limited (Current_Scope)
2124 ("extension of nonlimited type cannot have limited components",
2127 if Is_Interface (Root_Type (Current_Scope)) then
2129 ("\limitedness is not inherited from limited interface", N);
2130 Error_Msg_N ("\add LIMITED to type indication", N);
2133 Explain_Limited_Type (T, N);
2134 Set_Etype (Id, Any_Type);
2135 Set_Is_Limited_Composite (Current_Scope, False);
2137 elsif not Is_Derived_Type (Current_Scope)
2138 and then not Is_Limited_Record (Current_Scope)
2139 and then not Is_Concurrent_Type (Current_Scope)
2142 ("nonlimited tagged type cannot have limited components", N);
2143 Explain_Limited_Type (T, N);
2144 Set_Etype (Id, Any_Type);
2145 Set_Is_Limited_Composite (Current_Scope, False);
2149 -- If the component is an unconstrained task or protected type with
2150 -- discriminants, the component and the enclosing record are limited
2151 -- and the component is constrained by its default values. Compute
2152 -- its actual subtype, else it may be allocated the maximum size by
2153 -- the backend, and possibly overflow.
2155 if Is_Concurrent_Type (T)
2156 and then not Is_Constrained (T)
2157 and then Has_Discriminants (T)
2158 and then not Has_Discriminants (Current_Scope)
2161 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2164 Set_Etype (Id, Act_T);
2166 -- Rewrite component definition to use the constrained subtype
2168 Rewrite (Component_Definition (N),
2169 Make_Component_Definition (Loc,
2170 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2174 Set_Original_Record_Component (Id, Id);
2176 if Has_Aspects (N) then
2177 Analyze_Aspect_Specifications (N, Id);
2180 Analyze_Dimension (N);
2181 end Analyze_Component_Declaration;
2183 --------------------------
2184 -- Analyze_Declarations --
2185 --------------------------
2187 procedure Analyze_Declarations (L : List_Id) is
2190 procedure Adjust_Decl;
2191 -- Adjust Decl not to include implicit label declarations, since these
2192 -- have strange Sloc values that result in elaboration check problems.
2193 -- (They have the sloc of the label as found in the source, and that
2194 -- is ahead of the current declarative part).
2196 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id);
2197 -- Create the subprogram bodies which verify the run-time semantics of
2198 -- the pragmas listed below for each elibigle type found in declarative
2199 -- list Decls. The pragmas are:
2201 -- Default_Initial_Condition
2205 -- Context denotes the owner of the declarative list.
2207 procedure Check_Entry_Contracts;
2208 -- Perform a pre-analysis of the pre- and postconditions of an entry
2209 -- declaration. This must be done before full resolution and creation
2210 -- of the parameter block, etc. to catch illegal uses within the
2211 -- contract expression. Full analysis of the expression is done when
2212 -- the contract is processed.
2214 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2215 -- Determine whether Body_Decl denotes the body of a late controlled
2216 -- primitive (either Initialize, Adjust or Finalize). If this is the
2217 -- case, add a proper spec if the body lacks one. The spec is inserted
2218 -- before Body_Decl and immediately analyzed.
2220 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id);
2221 -- Spec_Id is the entity of a package that may define abstract states,
2222 -- and in the case of a child unit, whose ancestors may define abstract
2223 -- states. If the states have partial visible refinement, remove the
2224 -- partial visibility of each constituent at the end of the package
2225 -- spec and body declarations.
2227 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2228 -- Spec_Id is the entity of a package that may define abstract states.
2229 -- If the states have visible refinement, remove the visibility of each
2230 -- constituent at the end of the package body declaration.
2232 procedure Resolve_Aspects;
2233 -- Utility to resolve the expressions of aspects at the end of a list of
2236 function Uses_Unseen_Lib_Unit_Priv (Pkg : Entity_Id) return Boolean;
2237 -- Check if an inner package has entities within it that rely on library
2238 -- level private types where the full view has not been seen.
2244 procedure Adjust_Decl is
2246 while Present (Prev (Decl))
2247 and then Nkind (Decl) = N_Implicit_Label_Declaration
2253 ----------------------------
2254 -- Build_Assertion_Bodies --
2255 ----------------------------
2257 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id) is
2258 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id);
2259 -- Create the subprogram bodies which verify the run-time semantics
2260 -- of the pragmas listed below for type Typ. The pragmas are:
2262 -- Default_Initial_Condition
2266 -------------------------------------
2267 -- Build_Assertion_Bodies_For_Type --
2268 -------------------------------------
2270 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id) is
2272 -- Preanalyze and resolve the Default_Initial_Condition assertion
2273 -- expression at the end of the declarations to catch any errors.
2275 if Has_DIC (Typ) then
2276 Build_DIC_Procedure_Body (Typ);
2279 if Nkind (Context) = N_Package_Specification then
2281 -- Preanalyze and resolve the class-wide invariants of an
2282 -- interface at the end of whichever declarative part has the
2283 -- interface type. Note that an interface may be declared in
2284 -- any non-package declarative part, but reaching the end of
2285 -- such a declarative part will always freeze the type and
2286 -- generate the invariant procedure (see Freeze_Type).
2288 if Is_Interface (Typ) then
2290 -- Interfaces are treated as the partial view of a private
2291 -- type, in order to achieve uniformity with the general
2292 -- case. As a result, an interface receives only a "partial"
2293 -- invariant procedure, which is never called.
2295 if Has_Own_Invariants (Typ) then
2296 Build_Invariant_Procedure_Body
2298 Partial_Invariant => True);
2301 -- Preanalyze and resolve the invariants of a private type
2302 -- at the end of the visible declarations to catch potential
2303 -- errors. Inherited class-wide invariants are not included
2304 -- because they have already been resolved.
2306 elsif Decls = Visible_Declarations (Context)
2307 and then Ekind_In (Typ, E_Limited_Private_Type,
2309 E_Record_Type_With_Private)
2310 and then Has_Own_Invariants (Typ)
2312 Build_Invariant_Procedure_Body
2314 Partial_Invariant => True);
2316 -- Preanalyze and resolve the invariants of a private type's
2317 -- full view at the end of the private declarations to catch
2318 -- potential errors.
2320 elsif Decls = Private_Declarations (Context)
2321 and then not Is_Private_Type (Typ)
2322 and then Has_Private_Declaration (Typ)
2323 and then Has_Invariants (Typ)
2325 Build_Invariant_Procedure_Body (Typ);
2328 end Build_Assertion_Bodies_For_Type;
2333 Decl_Id : Entity_Id;
2335 -- Start of processing for Build_Assertion_Bodies
2338 Decl := First (Decls);
2339 while Present (Decl) loop
2340 if Is_Declaration (Decl) then
2341 Decl_Id := Defining_Entity (Decl);
2343 if Is_Type (Decl_Id) then
2344 Build_Assertion_Bodies_For_Type (Decl_Id);
2350 end Build_Assertion_Bodies;
2352 ---------------------------
2353 -- Check_Entry_Contracts --
2354 ---------------------------
2356 procedure Check_Entry_Contracts is
2362 Ent := First_Entity (Current_Scope);
2363 while Present (Ent) loop
2365 -- This only concerns entries with pre/postconditions
2367 if Ekind (Ent) = E_Entry
2368 and then Present (Contract (Ent))
2369 and then Present (Pre_Post_Conditions (Contract (Ent)))
2371 ASN := Pre_Post_Conditions (Contract (Ent));
2373 Install_Formals (Ent);
2375 -- Pre/postconditions are rewritten as Check pragmas. Analysis
2376 -- is performed on a copy of the pragma expression, to prevent
2377 -- modifying the original expression.
2379 while Present (ASN) loop
2380 if Nkind (ASN) = N_Pragma then
2384 (First (Pragma_Argument_Associations (ASN))));
2385 Set_Parent (Exp, ASN);
2387 Preanalyze_Assert_Expression (Exp, Standard_Boolean);
2390 ASN := Next_Pragma (ASN);
2398 end Check_Entry_Contracts;
2400 --------------------------------------
2401 -- Handle_Late_Controlled_Primitive --
2402 --------------------------------------
2404 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2405 Body_Spec : constant Node_Id := Specification (Body_Decl);
2406 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2407 Loc : constant Source_Ptr := Sloc (Body_Id);
2408 Params : constant List_Id :=
2409 Parameter_Specifications (Body_Spec);
2411 Spec_Id : Entity_Id;
2415 -- Consider only procedure bodies whose name matches one of the three
2416 -- controlled primitives.
2418 if Nkind (Body_Spec) /= N_Procedure_Specification
2419 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2425 -- A controlled primitive must have exactly one formal which is not
2426 -- an anonymous access type.
2428 elsif List_Length (Params) /= 1 then
2432 Typ := Parameter_Type (First (Params));
2434 if Nkind (Typ) = N_Access_Definition then
2440 -- The type of the formal must be derived from [Limited_]Controlled
2442 if not Is_Controlled (Entity (Typ)) then
2446 -- Check whether a specification exists for this body. We do not
2447 -- analyze the spec of the body in full, because it will be analyzed
2448 -- again when the body is properly analyzed, and we cannot create
2449 -- duplicate entries in the formals chain. We look for an explicit
2450 -- specification because the body may be an overriding operation and
2451 -- an inherited spec may be present.
2453 Spec_Id := Current_Entity (Body_Id);
2455 while Present (Spec_Id) loop
2456 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2457 and then Scope (Spec_Id) = Current_Scope
2458 and then Present (First_Formal (Spec_Id))
2459 and then No (Next_Formal (First_Formal (Spec_Id)))
2460 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2461 and then Comes_From_Source (Spec_Id)
2466 Spec_Id := Homonym (Spec_Id);
2469 -- At this point the body is known to be a late controlled primitive.
2470 -- Generate a matching spec and insert it before the body. Note the
2471 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2472 -- tree in this case.
2474 Spec := Copy_Separate_Tree (Body_Spec);
2476 -- Ensure that the subprogram declaration does not inherit the null
2477 -- indicator from the body as we now have a proper spec/body pair.
2479 Set_Null_Present (Spec, False);
2481 -- Ensure that the freeze node is inserted after the declaration of
2482 -- the primitive since its expansion will freeze the primitive.
2484 Decl := Make_Subprogram_Declaration (Loc, Specification => Spec);
2486 Insert_Before_And_Analyze (Body_Decl, Decl);
2487 end Handle_Late_Controlled_Primitive;
2489 ----------------------------------------
2490 -- Remove_Partial_Visible_Refinements --
2491 ----------------------------------------
2493 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id) is
2494 State_Elmt : Elmt_Id;
2496 if Present (Abstract_States (Spec_Id)) then
2497 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2498 while Present (State_Elmt) loop
2499 Set_Has_Partial_Visible_Refinement (Node (State_Elmt), False);
2500 Next_Elmt (State_Elmt);
2504 -- For a child unit, also hide the partial state refinement from
2505 -- ancestor packages.
2507 if Is_Child_Unit (Spec_Id) then
2508 Remove_Partial_Visible_Refinements (Scope (Spec_Id));
2510 end Remove_Partial_Visible_Refinements;
2512 --------------------------------
2513 -- Remove_Visible_Refinements --
2514 --------------------------------
2516 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2517 State_Elmt : Elmt_Id;
2519 if Present (Abstract_States (Spec_Id)) then
2520 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2521 while Present (State_Elmt) loop
2522 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2523 Next_Elmt (State_Elmt);
2526 end Remove_Visible_Refinements;
2528 ---------------------
2529 -- Resolve_Aspects --
2530 ---------------------
2532 procedure Resolve_Aspects is
2536 E := First_Entity (Current_Scope);
2537 while Present (E) loop
2538 Resolve_Aspect_Expressions (E);
2541 end Resolve_Aspects;
2543 -------------------------------
2544 -- Uses_Unseen_Lib_Unit_Priv --
2545 -------------------------------
2547 function Uses_Unseen_Lib_Unit_Priv (Pkg : Entity_Id) return Boolean is
2551 -- Avoid looking through scopes that do not meet the precondition of
2552 -- Pkg not being within a library unit spec.
2554 if not Is_Compilation_Unit (Pkg)
2555 and then not Is_Generic_Instance (Pkg)
2556 and then not In_Package_Body (Enclosing_Lib_Unit_Entity (Pkg))
2558 -- Loop through all entities in the current scope to identify
2559 -- an entity that depends on a private type.
2561 Curr := First_Entity (Pkg);
2563 if Nkind (Curr) in N_Entity
2564 and then Depends_On_Private (Curr)
2569 exit when Last_Entity (Current_Scope) = Curr;
2570 Curr := Next_Entity (Curr);
2575 end Uses_Unseen_Lib_Unit_Priv;
2579 Context : Node_Id := Empty;
2580 Freeze_From : Entity_Id := Empty;
2581 Next_Decl : Node_Id;
2583 Body_Seen : Boolean := False;
2584 -- Flag set when the first body [stub] is encountered
2586 -- Start of processing for Analyze_Declarations
2589 if Restriction_Check_Required (SPARK_05) then
2590 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2594 while Present (Decl) loop
2596 -- Package spec cannot contain a package declaration in SPARK
2598 if Nkind (Decl) = N_Package_Declaration
2599 and then Nkind (Parent (L)) = N_Package_Specification
2601 Check_SPARK_05_Restriction
2602 ("package specification cannot contain a package declaration",
2606 -- Complete analysis of declaration
2609 Next_Decl := Next (Decl);
2611 if No (Freeze_From) then
2612 Freeze_From := First_Entity (Current_Scope);
2615 -- At the end of a declarative part, freeze remaining entities
2616 -- declared in it. The end of the visible declarations of package
2617 -- specification is not the end of a declarative part if private
2618 -- declarations are present. The end of a package declaration is a
2619 -- freezing point only if it a library package. A task definition or
2620 -- protected type definition is not a freeze point either. Finally,
2621 -- we do not freeze entities in generic scopes, because there is no
2622 -- code generated for them and freeze nodes will be generated for
2625 -- The end of a package instantiation is not a freeze point, but
2626 -- for now we make it one, because the generic body is inserted
2627 -- (currently) immediately after. Generic instantiations will not
2628 -- be a freeze point once delayed freezing of bodies is implemented.
2629 -- (This is needed in any case for early instantiations ???).
2631 if No (Next_Decl) then
2632 if Nkind (Parent (L)) = N_Component_List then
2635 elsif Nkind_In (Parent (L), N_Protected_Definition,
2638 Check_Entry_Contracts;
2640 elsif Nkind (Parent (L)) /= N_Package_Specification then
2641 if Nkind (Parent (L)) = N_Package_Body then
2642 Freeze_From := First_Entity (Current_Scope);
2645 -- There may have been several freezing points previously,
2646 -- for example object declarations or subprogram bodies, but
2647 -- at the end of a declarative part we check freezing from
2648 -- the beginning, even though entities may already be frozen,
2649 -- in order to perform visibility checks on delayed aspects.
2652 Freeze_All (First_Entity (Current_Scope), Decl);
2653 Freeze_From := Last_Entity (Current_Scope);
2655 -- Current scope is a package specification
2657 elsif Scope (Current_Scope) /= Standard_Standard
2658 and then not Is_Child_Unit (Current_Scope)
2659 and then No (Generic_Parent (Parent (L)))
2661 -- This is needed in all cases to catch visibility errors in
2662 -- aspect expressions, but several large user tests are now
2663 -- rejected. Pending notification we restrict this call to
2670 elsif L /= Visible_Declarations (Parent (L))
2671 or else No (Private_Declarations (Parent (L)))
2672 or else Is_Empty_List (Private_Declarations (Parent (L)))
2676 -- End of a package declaration
2678 -- In compilation mode the expansion of freeze node takes care
2679 -- of resolving expressions of all aspects in the list. In ASIS
2680 -- mode this must be done explicitly.
2683 and then Scope (Current_Scope) = Standard_Standard
2688 -- This is a freeze point because it is the end of a
2689 -- compilation unit.
2691 Freeze_All (First_Entity (Current_Scope), Decl);
2692 Freeze_From := Last_Entity (Current_Scope);
2694 -- At the end of the visible declarations the expressions in
2695 -- aspects of all entities declared so far must be resolved.
2696 -- The entities themselves might be frozen later, and the
2697 -- generated pragmas and attribute definition clauses analyzed
2698 -- in full at that point, but name resolution must take place
2700 -- In addition to being the proper semantics, this is mandatory
2701 -- within generic units, because global name capture requires
2702 -- those expressions to be analyzed, given that the generated
2703 -- pragmas do not appear in the original generic tree.
2705 elsif Serious_Errors_Detected = 0 then
2709 -- If next node is a body then freeze all types before the body.
2710 -- An exception occurs for some expander-generated bodies. If these
2711 -- are generated at places where in general language rules would not
2712 -- allow a freeze point, then we assume that the expander has
2713 -- explicitly checked that all required types are properly frozen,
2714 -- and we do not cause general freezing here. This special circuit
2715 -- is used when the encountered body is marked as having already
2718 -- In all other cases (bodies that come from source, and expander
2719 -- generated bodies that have not been analyzed yet), freeze all
2720 -- types now. Note that in the latter case, the expander must take
2721 -- care to attach the bodies at a proper place in the tree so as to
2722 -- not cause unwanted freezing at that point.
2724 -- It is also necessary to check for a case where both an expression
2725 -- function is used and the current scope depends on an unseen
2726 -- private type from a library unit, otherwise premature freezing of
2727 -- the private type will occur.
2729 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl)
2730 and then ((Nkind (Next_Decl) /= N_Subprogram_Body
2731 or else not Was_Expression_Function (Next_Decl))
2732 or else not Uses_Unseen_Lib_Unit_Priv (Current_Scope))
2734 -- When a controlled type is frozen, the expander generates stream
2735 -- and controlled-type support routines. If the freeze is caused
2736 -- by the stand-alone body of Initialize, Adjust, or Finalize, the
2737 -- expander will end up using the wrong version of these routines,
2738 -- as the body has not been processed yet. To remedy this, detect
2739 -- a late controlled primitive and create a proper spec for it.
2740 -- This ensures that the primitive will override its inherited
2741 -- counterpart before the freeze takes place.
2743 -- If the declaration we just processed is a body, do not attempt
2744 -- to examine Next_Decl as the late primitive idiom can only apply
2745 -- to the first encountered body.
2747 -- The spec of the late primitive is not generated in ASIS mode to
2748 -- ensure a consistent list of primitives that indicates the true
2749 -- semantic structure of the program (which is not relevant when
2750 -- generating executable code).
2752 -- ??? A cleaner approach may be possible and/or this solution
2753 -- could be extended to general-purpose late primitives, TBD.
2756 and then not Body_Seen
2757 and then not Is_Body (Decl)
2761 if Nkind (Next_Decl) = N_Subprogram_Body then
2762 Handle_Late_Controlled_Primitive (Next_Decl);
2768 -- The generated body of an expression function does not freeze,
2769 -- unless it is a completion, in which case only the expression
2770 -- itself freezes. This is handled when the body itself is
2771 -- analyzed (see Freeze_Expr_Types, sem_ch6.adb).
2773 Freeze_All (Freeze_From, Decl);
2774 Freeze_From := Last_Entity (Current_Scope);
2780 -- Post-freezing actions
2783 Context := Parent (L);
2785 -- Analyze the contracts of packages and their bodies
2787 if Nkind (Context) = N_Package_Specification then
2789 -- When a package has private declarations, its contract must be
2790 -- analyzed at the end of the said declarations. This way both the
2791 -- analysis and freeze actions are properly synchronized in case
2792 -- of private type use within the contract.
2794 if L = Private_Declarations (Context) then
2795 Analyze_Package_Contract (Defining_Entity (Context));
2797 -- Otherwise the contract is analyzed at the end of the visible
2800 elsif L = Visible_Declarations (Context)
2801 and then No (Private_Declarations (Context))
2803 Analyze_Package_Contract (Defining_Entity (Context));
2806 elsif Nkind (Context) = N_Package_Body then
2807 Analyze_Package_Body_Contract (Defining_Entity (Context));
2810 -- Analyze the contracts of various constructs now due to the delayed
2811 -- visibility needs of their aspects and pragmas.
2813 Analyze_Contracts (L);
2815 if Nkind (Context) = N_Package_Body then
2817 -- Ensure that all abstract states and objects declared in the
2818 -- state space of a package body are utilized as constituents.
2820 Check_Unused_Body_States (Defining_Entity (Context));
2822 -- State refinements are visible up to the end of the package body
2823 -- declarations. Hide the state refinements from visibility to
2824 -- restore the original state conditions.
2826 Remove_Visible_Refinements (Corresponding_Spec (Context));
2827 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2829 elsif Nkind (Context) = N_Package_Declaration then
2831 -- Partial state refinements are visible up to the end of the
2832 -- package spec declarations. Hide the partial state refinements
2833 -- from visibility to restore the original state conditions.
2835 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2838 -- Verify that all abstract states found in any package declared in
2839 -- the input declarative list have proper refinements. The check is
2840 -- performed only when the context denotes a block, entry, package,
2841 -- protected, subprogram, or task body (SPARK RM 7.2.2(3)).
2843 Check_State_Refinements (Context);
2845 -- Create the subprogram bodies which verify the run-time semantics
2846 -- of pragmas Default_Initial_Condition and [Type_]Invariant for all
2847 -- types within the current declarative list. This ensures that all
2848 -- assertion expressions are preanalyzed and resolved at the end of
2849 -- the declarative part. Note that the resolution happens even when
2850 -- freezing does not take place.
2852 Build_Assertion_Bodies (L, Context);
2854 end Analyze_Declarations;
2856 -----------------------------------
2857 -- Analyze_Full_Type_Declaration --
2858 -----------------------------------
2860 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2861 Def : constant Node_Id := Type_Definition (N);
2862 Def_Id : constant Entity_Id := Defining_Identifier (N);
2866 Is_Remote : constant Boolean :=
2867 (Is_Remote_Types (Current_Scope)
2868 or else Is_Remote_Call_Interface (Current_Scope))
2869 and then not (In_Private_Part (Current_Scope)
2870 or else In_Package_Body (Current_Scope));
2872 procedure Check_Nonoverridable_Aspects;
2873 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2874 -- be overridden, and can only be confirmed on derivation.
2876 procedure Check_Ops_From_Incomplete_Type;
2877 -- If there is a tagged incomplete partial view of the type, traverse
2878 -- the primitives of the incomplete view and change the type of any
2879 -- controlling formals and result to indicate the full view. The
2880 -- primitives will be added to the full type's primitive operations
2881 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2882 -- is called from Process_Incomplete_Dependents).
2884 ----------------------------------
2885 -- Check_Nonoverridable_Aspects --
2886 ----------------------------------
2888 procedure Check_Nonoverridable_Aspects is
2889 function Get_Aspect_Spec
2891 Aspect_Name : Name_Id) return Node_Id;
2892 -- Check whether a list of aspect specifications includes an entry
2893 -- for a specific aspect. The list is either that of a partial or
2896 ---------------------
2897 -- Get_Aspect_Spec --
2898 ---------------------
2900 function Get_Aspect_Spec
2902 Aspect_Name : Name_Id) return Node_Id
2907 Spec := First (Specs);
2908 while Present (Spec) loop
2909 if Chars (Identifier (Spec)) = Aspect_Name then
2916 end Get_Aspect_Spec;
2920 Prev_Aspects : constant List_Id :=
2921 Aspect_Specifications (Parent (Def_Id));
2922 Par_Type : Entity_Id;
2923 Prev_Aspect : Node_Id;
2925 -- Start of processing for Check_Nonoverridable_Aspects
2928 -- Get parent type of derived type. Note that Prev is the entity in
2929 -- the partial declaration, but its contents are now those of full
2930 -- view, while Def_Id reflects the partial view.
2932 if Is_Private_Type (Def_Id) then
2933 Par_Type := Etype (Full_View (Def_Id));
2935 Par_Type := Etype (Def_Id);
2938 -- If there is an inherited Implicit_Dereference, verify that it is
2939 -- made explicit in the partial view.
2941 if Has_Discriminants (Base_Type (Par_Type))
2942 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2943 and then Present (Discriminant_Specifications (Parent (Prev)))
2944 and then Present (Get_Reference_Discriminant (Par_Type))
2947 Get_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference);
2951 (Discriminant_Specifications
2952 (Original_Node (Parent (Prev))))
2955 ("type does not inherit implicit dereference", Prev);
2958 -- If one of the views has the aspect specified, verify that it
2959 -- is consistent with that of the parent.
2962 Par_Discr : constant Entity_Id :=
2963 Get_Reference_Discriminant (Par_Type);
2964 Cur_Discr : constant Entity_Id :=
2965 Get_Reference_Discriminant (Prev);
2968 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2969 Error_Msg_N ("aspect incosistent with that of parent", N);
2972 -- Check that specification in partial view matches the
2973 -- inherited aspect. Compare names directly because aspect
2974 -- expression may not be analyzed.
2976 if Present (Prev_Aspect)
2977 and then Nkind (Expression (Prev_Aspect)) = N_Identifier
2978 and then Chars (Expression (Prev_Aspect)) /=
2982 ("aspect incosistent with that of parent", N);
2988 -- TBD : other nonoverridable aspects.
2989 end Check_Nonoverridable_Aspects;
2991 ------------------------------------
2992 -- Check_Ops_From_Incomplete_Type --
2993 ------------------------------------
2995 procedure Check_Ops_From_Incomplete_Type is
3002 and then Ekind (Prev) = E_Incomplete_Type
3003 and then Is_Tagged_Type (Prev)
3004 and then Is_Tagged_Type (T)
3006 Elmt := First_Elmt (Primitive_Operations (Prev));
3007 while Present (Elmt) loop
3010 Formal := First_Formal (Op);
3011 while Present (Formal) loop
3012 if Etype (Formal) = Prev then
3013 Set_Etype (Formal, T);
3016 Next_Formal (Formal);
3019 if Etype (Op) = Prev then
3026 end Check_Ops_From_Incomplete_Type;
3028 -- Start of processing for Analyze_Full_Type_Declaration
3031 Prev := Find_Type_Name (N);
3033 -- The full view, if present, now points to the current type. If there
3034 -- is an incomplete partial view, set a link to it, to simplify the
3035 -- retrieval of primitive operations of the type.
3037 -- Ada 2005 (AI-50217): If the type was previously decorated when
3038 -- imported through a LIMITED WITH clause, it appears as incomplete
3039 -- but has no full view.
3041 if Ekind (Prev) = E_Incomplete_Type
3042 and then Present (Full_View (Prev))
3044 T := Full_View (Prev);
3045 Set_Incomplete_View (N, Parent (Prev));
3050 Set_Is_Pure (T, Is_Pure (Current_Scope));
3052 -- We set the flag Is_First_Subtype here. It is needed to set the
3053 -- corresponding flag for the Implicit class-wide-type created
3054 -- during tagged types processing.
3056 Set_Is_First_Subtype (T, True);
3058 -- Only composite types other than array types are allowed to have
3063 -- For derived types, the rule will be checked once we've figured
3064 -- out the parent type.
3066 when N_Derived_Type_Definition =>
3069 -- For record types, discriminants are allowed, unless we are in
3072 when N_Record_Definition =>
3073 if Present (Discriminant_Specifications (N)) then
3074 Check_SPARK_05_Restriction
3075 ("discriminant type is not allowed",
3077 (First (Discriminant_Specifications (N))));
3081 if Present (Discriminant_Specifications (N)) then
3083 ("elementary or array type cannot have discriminants",
3085 (First (Discriminant_Specifications (N))));
3089 -- Elaborate the type definition according to kind, and generate
3090 -- subsidiary (implicit) subtypes where needed. We skip this if it was
3091 -- already done (this happens during the reanalysis that follows a call
3092 -- to the high level optimizer).
3094 if not Analyzed (T) then
3098 when N_Access_To_Subprogram_Definition =>
3099 Access_Subprogram_Declaration (T, Def);
3101 -- If this is a remote access to subprogram, we must create the
3102 -- equivalent fat pointer type, and related subprograms.
3105 Process_Remote_AST_Declaration (N);
3108 -- Validate categorization rule against access type declaration
3109 -- usually a violation in Pure unit, Shared_Passive unit.
3111 Validate_Access_Type_Declaration (T, N);
3113 when N_Access_To_Object_Definition =>
3114 Access_Type_Declaration (T, Def);
3116 -- Validate categorization rule against access type declaration
3117 -- usually a violation in Pure unit, Shared_Passive unit.
3119 Validate_Access_Type_Declaration (T, N);
3121 -- If we are in a Remote_Call_Interface package and define a
3122 -- RACW, then calling stubs and specific stream attributes
3126 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
3128 Add_RACW_Features (Def_Id);
3131 when N_Array_Type_Definition =>
3132 Array_Type_Declaration (T, Def);
3134 when N_Derived_Type_Definition =>
3135 Derived_Type_Declaration (T, N, T /= Def_Id);
3137 -- Inherit predicates from parent, and protect against illegal
3140 if Is_Type (T) and then Has_Predicates (T) then
3141 Set_Has_Predicates (Def_Id);
3144 when N_Enumeration_Type_Definition =>
3145 Enumeration_Type_Declaration (T, Def);
3147 when N_Floating_Point_Definition =>
3148 Floating_Point_Type_Declaration (T, Def);
3150 when N_Decimal_Fixed_Point_Definition =>
3151 Decimal_Fixed_Point_Type_Declaration (T, Def);
3153 when N_Ordinary_Fixed_Point_Definition =>
3154 Ordinary_Fixed_Point_Type_Declaration (T, Def);
3156 when N_Signed_Integer_Type_Definition =>
3157 Signed_Integer_Type_Declaration (T, Def);
3159 when N_Modular_Type_Definition =>
3160 Modular_Type_Declaration (T, Def);
3162 when N_Record_Definition =>
3163 Record_Type_Declaration (T, N, Prev);
3165 -- If declaration has a parse error, nothing to elaborate.
3171 raise Program_Error;
3175 if Etype (T) = Any_Type then
3179 -- Controlled type is not allowed in SPARK
3181 if Is_Visibly_Controlled (T) then
3182 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
3185 -- Some common processing for all types
3187 Set_Depends_On_Private (T, Has_Private_Component (T));
3188 Check_Ops_From_Incomplete_Type;
3190 -- Both the declared entity, and its anonymous base type if one was
3191 -- created, need freeze nodes allocated.
3194 B : constant Entity_Id := Base_Type (T);
3197 -- In the case where the base type differs from the first subtype, we
3198 -- pre-allocate a freeze node, and set the proper link to the first
3199 -- subtype. Freeze_Entity will use this preallocated freeze node when
3200 -- it freezes the entity.
3202 -- This does not apply if the base type is a generic type, whose
3203 -- declaration is independent of the current derived definition.
3205 if B /= T and then not Is_Generic_Type (B) then
3206 Ensure_Freeze_Node (B);
3207 Set_First_Subtype_Link (Freeze_Node (B), T);
3210 -- A type that is imported through a limited_with clause cannot
3211 -- generate any code, and thus need not be frozen. However, an access
3212 -- type with an imported designated type needs a finalization list,
3213 -- which may be referenced in some other package that has non-limited
3214 -- visibility on the designated type. Thus we must create the
3215 -- finalization list at the point the access type is frozen, to
3216 -- prevent unsatisfied references at link time.
3218 if not From_Limited_With (T) or else Is_Access_Type (T) then
3219 Set_Has_Delayed_Freeze (T);
3223 -- Case where T is the full declaration of some private type which has
3224 -- been swapped in Defining_Identifier (N).
3226 if T /= Def_Id and then Is_Private_Type (Def_Id) then
3227 Process_Full_View (N, T, Def_Id);
3229 -- Record the reference. The form of this is a little strange, since
3230 -- the full declaration has been swapped in. So the first parameter
3231 -- here represents the entity to which a reference is made which is
3232 -- the "real" entity, i.e. the one swapped in, and the second
3233 -- parameter provides the reference location.
3235 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
3236 -- since we don't want a complaint about the full type being an
3237 -- unwanted reference to the private type
3240 B : constant Boolean := Has_Pragma_Unreferenced (T);
3242 Set_Has_Pragma_Unreferenced (T, False);
3243 Generate_Reference (T, T, 'c');
3244 Set_Has_Pragma_Unreferenced (T, B);
3247 Set_Completion_Referenced (Def_Id);
3249 -- For completion of incomplete type, process incomplete dependents
3250 -- and always mark the full type as referenced (it is the incomplete
3251 -- type that we get for any real reference).
3253 elsif Ekind (Prev) = E_Incomplete_Type then
3254 Process_Incomplete_Dependents (N, T, Prev);
3255 Generate_Reference (Prev, Def_Id, 'c');
3256 Set_Completion_Referenced (Def_Id);
3258 -- If not private type or incomplete type completion, this is a real
3259 -- definition of a new entity, so record it.
3262 Generate_Definition (Def_Id);
3265 -- Propagate any pending access types whose finalization masters need to
3266 -- be fully initialized from the partial to the full view. Guard against
3267 -- an illegal full view that remains unanalyzed.
3269 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
3270 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
3273 if Chars (Scope (Def_Id)) = Name_System
3274 and then Chars (Def_Id) = Name_Address
3275 and then In_Predefined_Unit (N)
3277 Set_Is_Descendant_Of_Address (Def_Id);
3278 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
3279 Set_Is_Descendant_Of_Address (Prev);
3282 Set_Optimize_Alignment_Flags (Def_Id);
3283 Check_Eliminated (Def_Id);
3285 -- If the declaration is a completion and aspects are present, apply
3286 -- them to the entity for the type which is currently the partial
3287 -- view, but which is the one that will be frozen.
3289 if Has_Aspects (N) then
3291 -- In most cases the partial view is a private type, and both views
3292 -- appear in different declarative parts. In the unusual case where
3293 -- the partial view is incomplete, perform the analysis on the
3294 -- full view, to prevent freezing anomalies with the corresponding
3295 -- class-wide type, which otherwise might be frozen before the
3296 -- dispatch table is built.
3299 and then Ekind (Prev) /= E_Incomplete_Type
3301 Analyze_Aspect_Specifications (N, Prev);
3306 Analyze_Aspect_Specifications (N, Def_Id);
3310 if Is_Derived_Type (Prev)
3311 and then Def_Id /= Prev
3313 Check_Nonoverridable_Aspects;
3315 end Analyze_Full_Type_Declaration;
3317 ----------------------------------
3318 -- Analyze_Incomplete_Type_Decl --
3319 ----------------------------------
3321 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3322 F : constant Boolean := Is_Pure (Current_Scope);
3326 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3328 Generate_Definition (Defining_Identifier (N));
3330 -- Process an incomplete declaration. The identifier must not have been
3331 -- declared already in the scope. However, an incomplete declaration may
3332 -- appear in the private part of a package, for a private type that has
3333 -- already been declared.
3335 -- In this case, the discriminants (if any) must match
3337 T := Find_Type_Name (N);
3339 Set_Ekind (T, E_Incomplete_Type);
3340 Init_Size_Align (T);
3341 Set_Is_First_Subtype (T, True);
3344 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3345 -- incomplete types.
3347 if Tagged_Present (N) then
3348 Set_Is_Tagged_Type (T, True);
3349 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3350 Make_Class_Wide_Type (T);
3351 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3354 Set_Stored_Constraint (T, No_Elist);
3356 if Present (Discriminant_Specifications (N)) then
3358 Process_Discriminants (N);
3362 -- If the type has discriminants, nontrivial subtypes may be declared
3363 -- before the full view of the type. The full views of those subtypes
3364 -- will be built after the full view of the type.
3366 Set_Private_Dependents (T, New_Elmt_List);
3368 end Analyze_Incomplete_Type_Decl;
3370 -----------------------------------
3371 -- Analyze_Interface_Declaration --
3372 -----------------------------------
3374 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3375 CW : constant Entity_Id := Class_Wide_Type (T);
3378 Set_Is_Tagged_Type (T);
3379 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3381 Set_Is_Limited_Record (T, Limited_Present (Def)
3382 or else Task_Present (Def)
3383 or else Protected_Present (Def)
3384 or else Synchronized_Present (Def));
3386 -- Type is abstract if full declaration carries keyword, or if previous
3387 -- partial view did.
3389 Set_Is_Abstract_Type (T);
3390 Set_Is_Interface (T);
3392 -- Type is a limited interface if it includes the keyword limited, task,
3393 -- protected, or synchronized.
3395 Set_Is_Limited_Interface
3396 (T, Limited_Present (Def)
3397 or else Protected_Present (Def)
3398 or else Synchronized_Present (Def)
3399 or else Task_Present (Def));
3401 Set_Interfaces (T, New_Elmt_List);
3402 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3404 -- Complete the decoration of the class-wide entity if it was already
3405 -- built (i.e. during the creation of the limited view)
3407 if Present (CW) then
3408 Set_Is_Interface (CW);
3409 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3412 -- Check runtime support for synchronized interfaces
3414 if (Is_Task_Interface (T)
3415 or else Is_Protected_Interface (T)
3416 or else Is_Synchronized_Interface (T))
3417 and then not RTE_Available (RE_Select_Specific_Data)
3419 Error_Msg_CRT ("synchronized interfaces", T);
3421 end Analyze_Interface_Declaration;
3423 -----------------------------
3424 -- Analyze_Itype_Reference --
3425 -----------------------------
3427 -- Nothing to do. This node is placed in the tree only for the benefit of
3428 -- back end processing, and has no effect on the semantic processing.
3430 procedure Analyze_Itype_Reference (N : Node_Id) is
3432 pragma Assert (Is_Itype (Itype (N)));
3434 end Analyze_Itype_Reference;
3436 --------------------------------
3437 -- Analyze_Number_Declaration --
3438 --------------------------------
3440 procedure Analyze_Number_Declaration (N : Node_Id) is
3441 E : constant Node_Id := Expression (N);
3442 Id : constant Entity_Id := Defining_Identifier (N);
3443 Index : Interp_Index;
3448 Generate_Definition (Id);
3451 -- This is an optimization of a common case of an integer literal
3453 if Nkind (E) = N_Integer_Literal then
3454 Set_Is_Static_Expression (E, True);
3455 Set_Etype (E, Universal_Integer);
3457 Set_Etype (Id, Universal_Integer);
3458 Set_Ekind (Id, E_Named_Integer);
3459 Set_Is_Frozen (Id, True);
3463 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3465 -- Process expression, replacing error by integer zero, to avoid
3466 -- cascaded errors or aborts further along in the processing
3468 -- Replace Error by integer zero, which seems least likely to cause
3472 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3473 Set_Error_Posted (E);
3478 -- Verify that the expression is static and numeric. If
3479 -- the expression is overloaded, we apply the preference
3480 -- rule that favors root numeric types.
3482 if not Is_Overloaded (E) then
3484 if Has_Dynamic_Predicate_Aspect (T) then
3486 ("subtype has dynamic predicate, "
3487 & "not allowed in number declaration", N);
3493 Get_First_Interp (E, Index, It);
3494 while Present (It.Typ) loop
3495 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3496 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3498 if T = Any_Type then
3501 elsif It.Typ = Universal_Real
3503 It.Typ = Universal_Integer
3505 -- Choose universal interpretation over any other
3512 Get_Next_Interp (Index, It);
3516 if Is_Integer_Type (T) then
3518 Set_Etype (Id, Universal_Integer);
3519 Set_Ekind (Id, E_Named_Integer);
3521 elsif Is_Real_Type (T) then
3523 -- Because the real value is converted to universal_real, this is a
3524 -- legal context for a universal fixed expression.
3526 if T = Universal_Fixed then
3528 Loc : constant Source_Ptr := Sloc (N);
3529 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3531 New_Occurrence_Of (Universal_Real, Loc),
3532 Expression => Relocate_Node (E));
3539 elsif T = Any_Fixed then
3540 Error_Msg_N ("illegal context for mixed mode operation", E);
3542 -- Expression is of the form : universal_fixed * integer. Try to
3543 -- resolve as universal_real.
3545 T := Universal_Real;
3550 Set_Etype (Id, Universal_Real);
3551 Set_Ekind (Id, E_Named_Real);
3554 Wrong_Type (E, Any_Numeric);
3558 Set_Ekind (Id, E_Constant);
3559 Set_Never_Set_In_Source (Id, True);
3560 Set_Is_True_Constant (Id, True);
3564 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3565 Set_Etype (E, Etype (Id));
3568 if not Is_OK_Static_Expression (E) then
3569 Flag_Non_Static_Expr
3570 ("non-static expression used in number declaration!", E);
3571 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3572 Set_Etype (E, Any_Type);
3575 Analyze_Dimension (N);
3576 end Analyze_Number_Declaration;
3578 --------------------------------
3579 -- Analyze_Object_Declaration --
3580 --------------------------------
3582 -- WARNING: This routine manages Ghost regions. Return statements must be
3583 -- replaced by gotos which jump to the end of the routine and restore the
3586 procedure Analyze_Object_Declaration (N : Node_Id) is
3587 Loc : constant Source_Ptr := Sloc (N);
3588 Id : constant Entity_Id := Defining_Identifier (N);
3592 E : Node_Id := Expression (N);
3593 -- E is set to Expression (N) throughout this routine. When Expression
3594 -- (N) is modified, E is changed accordingly.
3596 Prev_Entity : Entity_Id := Empty;
3598 procedure Check_Dynamic_Object (Typ : Entity_Id);
3599 -- A library-level object with non-static discriminant constraints may
3600 -- require dynamic allocation. The declaration is illegal if the
3601 -- profile includes the restriction No_Implicit_Heap_Allocations.
3603 procedure Check_For_Null_Excluding_Components
3604 (Obj_Typ : Entity_Id;
3605 Obj_Decl : Node_Id);
3606 -- Verify that each null-excluding component of object declaration
3607 -- Obj_Decl carrying type Obj_Typ has explicit initialization. Emit
3608 -- a compile-time warning if this is not the case.
3610 function Count_Tasks (T : Entity_Id) return Uint;
3611 -- This function is called when a non-generic library level object of a
3612 -- task type is declared. Its function is to count the static number of
3613 -- tasks declared within the type (it is only called if Has_Task is set
3614 -- for T). As a side effect, if an array of tasks with non-static bounds
3615 -- or a variant record type is encountered, Check_Restriction is called
3616 -- indicating the count is unknown.
3618 function Delayed_Aspect_Present return Boolean;
3619 -- If the declaration has an expression that is an aggregate, and it
3620 -- has aspects that require delayed analysis, the resolution of the
3621 -- aggregate must be deferred to the freeze point of the objet. This
3622 -- special processing was created for address clauses, but it must
3623 -- also apply to Alignment. This must be done before the aspect
3624 -- specifications are analyzed because we must handle the aggregate
3625 -- before the analysis of the object declaration is complete.
3627 -- Any other relevant delayed aspects on object declarations ???
3629 --------------------------
3630 -- Check_Dynamic_Object --
3631 --------------------------
3633 procedure Check_Dynamic_Object (Typ : Entity_Id) is
3635 Obj_Type : Entity_Id;
3640 if Is_Private_Type (Obj_Type)
3641 and then Present (Full_View (Obj_Type))
3643 Obj_Type := Full_View (Obj_Type);
3646 if Known_Static_Esize (Obj_Type) then
3650 if Restriction_Active (No_Implicit_Heap_Allocations)
3651 and then Expander_Active
3652 and then Has_Discriminants (Obj_Type)
3654 Comp := First_Component (Obj_Type);
3655 while Present (Comp) loop
3656 if Known_Static_Esize (Etype (Comp))
3657 or else Size_Known_At_Compile_Time (Etype (Comp))
3661 elsif not Discriminated_Size (Comp)
3662 and then Comes_From_Source (Comp)
3665 ("component& of non-static size will violate restriction "
3666 & "No_Implicit_Heap_Allocation?", N, Comp);
3668 elsif Is_Record_Type (Etype (Comp)) then
3669 Check_Dynamic_Object (Etype (Comp));
3672 Next_Component (Comp);
3675 end Check_Dynamic_Object;
3677 -----------------------------------------
3678 -- Check_For_Null_Excluding_Components --
3679 -----------------------------------------
3681 procedure Check_For_Null_Excluding_Components
3682 (Obj_Typ : Entity_Id;
3685 procedure Check_Component
3686 (Comp_Typ : Entity_Id;
3687 Comp_Decl : Node_Id := Empty;
3688 Array_Comp : Boolean := False);
3689 -- Apply a compile-time null-exclusion check on a component denoted
3690 -- by its declaration Comp_Decl and type Comp_Typ, and all of its
3691 -- subcomponents (if any).
3693 ---------------------
3694 -- Check_Component --
3695 ---------------------
3697 procedure Check_Component
3698 (Comp_Typ : Entity_Id;
3699 Comp_Decl : Node_Id := Empty;
3700 Array_Comp : Boolean := False)
3706 -- Do not consider internally-generated components or those that
3707 -- are already initialized.
3709 if Present (Comp_Decl)
3710 and then (not Comes_From_Source (Comp_Decl)
3711 or else Present (Expression (Comp_Decl)))
3716 if Is_Incomplete_Or_Private_Type (Comp_Typ)
3717 and then Present (Full_View (Comp_Typ))
3719 T := Full_View (Comp_Typ);
3724 -- Verify a component of a null-excluding access type
3726 if Is_Access_Type (T)
3727 and then Can_Never_Be_Null (T)
3729 if Comp_Decl = Obj_Decl then
3730 Null_Exclusion_Static_Checks
3733 Array_Comp => Array_Comp);
3736 Null_Exclusion_Static_Checks
3739 Array_Comp => Array_Comp);
3742 -- Check array components
3744 elsif Is_Array_Type (T) then
3746 -- There is no suitable component when the object is of an
3747 -- array type. However, a namable component may appear at some
3748 -- point during the recursive inspection, but not at the top
3749 -- level. At the top level just indicate array component case.
3751 if Comp_Decl = Obj_Decl then
3752 Check_Component (Component_Type (T), Array_Comp => True);
3754 Check_Component (Component_Type (T), Comp_Decl);
3757 -- Verify all components of type T
3759 -- Note: No checks are performed on types with discriminants due
3760 -- to complexities involving variants. ???
3762 elsif (Is_Concurrent_Type (T)
3763 or else Is_Incomplete_Or_Private_Type (T)
3764 or else Is_Record_Type (T))
3765 and then not Has_Discriminants (T)
3767 Comp := First_Component (T);
3768 while Present (Comp) loop
3769 Check_Component (Etype (Comp), Parent (Comp));
3771 Comp := Next_Component (Comp);
3774 end Check_Component;
3776 -- Start processing for Check_For_Null_Excluding_Components
3779 Check_Component (Obj_Typ, Obj_Decl);
3780 end Check_For_Null_Excluding_Components;
3786 function Count_Tasks (T : Entity_Id) return Uint is
3792 if Is_Task_Type (T) then
3795 elsif Is_Record_Type (T) then
3796 if Has_Discriminants (T) then
3797 Check_Restriction (Max_Tasks, N);
3802 C := First_Component (T);
3803 while Present (C) loop
3804 V := V + Count_Tasks (Etype (C));
3811 elsif Is_Array_Type (T) then
3812 X := First_Index (T);
3813 V := Count_Tasks (Component_Type (T));
3814 while Present (X) loop
3817 if not Is_OK_Static_Subtype (C) then
3818 Check_Restriction (Max_Tasks, N);
3821 V := V * (UI_Max (Uint_0,
3822 Expr_Value (Type_High_Bound (C)) -
3823 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3836 ----------------------------
3837 -- Delayed_Aspect_Present --
3838 ----------------------------
3840 function Delayed_Aspect_Present return Boolean is
3845 if Present (Aspect_Specifications (N)) then
3846 A := First (Aspect_Specifications (N));
3847 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3848 while Present (A) loop
3849 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3858 end Delayed_Aspect_Present;
3862 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3863 -- Save the Ghost mode to restore on exit
3865 Related_Id : Entity_Id;
3867 -- Start of processing for Analyze_Object_Declaration
3870 -- There are three kinds of implicit types generated by an
3871 -- object declaration:
3873 -- 1. Those generated by the original Object Definition
3875 -- 2. Those generated by the Expression
3877 -- 3. Those used to constrain the Object Definition with the
3878 -- expression constraints when the definition is unconstrained.
3880 -- They must be generated in this order to avoid order of elaboration
3881 -- issues. Thus the first step (after entering the name) is to analyze
3882 -- the object definition.
3884 if Constant_Present (N) then
3885 Prev_Entity := Current_Entity_In_Scope (Id);
3887 if Present (Prev_Entity)
3889 -- If the homograph is an implicit subprogram, it is overridden
3890 -- by the current declaration.
3892 ((Is_Overloadable (Prev_Entity)
3893 and then Is_Inherited_Operation (Prev_Entity))
3895 -- The current object is a discriminal generated for an entry
3896 -- family index. Even though the index is a constant, in this
3897 -- particular context there is no true constant redeclaration.
3898 -- Enter_Name will handle the visibility.
3901 (Is_Discriminal (Id)
3902 and then Ekind (Discriminal_Link (Id)) =
3903 E_Entry_Index_Parameter)
3905 -- The current object is the renaming for a generic declared
3906 -- within the instance.
3909 (Ekind (Prev_Entity) = E_Package
3910 and then Nkind (Parent (Prev_Entity)) =
3911 N_Package_Renaming_Declaration
3912 and then not Comes_From_Source (Prev_Entity)
3914 Is_Generic_Instance (Renamed_Entity (Prev_Entity)))
3916 -- The entity may be a homonym of a private component of the
3917 -- enclosing protected object, for which we create a local
3918 -- renaming declaration. The declaration is legal, even if
3919 -- useless when it just captures that component.
3922 (Ekind (Scope (Current_Scope)) = E_Protected_Type
3923 and then Nkind (Parent (Prev_Entity)) =
3924 N_Object_Renaming_Declaration))
3926 Prev_Entity := Empty;
3930 if Present (Prev_Entity) then
3932 -- The object declaration is Ghost when it completes a deferred Ghost
3935 Mark_And_Set_Ghost_Completion (N, Prev_Entity);
3937 Constant_Redeclaration (Id, N, T);
3939 Generate_Reference (Prev_Entity, Id, 'c');
3940 Set_Completion_Referenced (Id);
3942 if Error_Posted (N) then
3944 -- Type mismatch or illegal redeclaration; do not analyze
3945 -- expression to avoid cascaded errors.
3947 T := Find_Type_Of_Object (Object_Definition (N), N);
3949 Set_Ekind (Id, E_Variable);
3953 -- In the normal case, enter identifier at the start to catch premature
3954 -- usage in the initialization expression.
3957 Generate_Definition (Id);
3960 Mark_Coextensions (N, Object_Definition (N));
3962 T := Find_Type_Of_Object (Object_Definition (N), N);
3964 if Nkind (Object_Definition (N)) = N_Access_Definition
3966 (Access_To_Subprogram_Definition (Object_Definition (N)))
3967 and then Protected_Present
3968 (Access_To_Subprogram_Definition (Object_Definition (N)))
3970 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3973 if Error_Posted (Id) then
3975 Set_Ekind (Id, E_Variable);
3980 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3981 -- out some static checks.
3983 if Ada_Version >= Ada_2005 then
3985 -- In case of aggregates we must also take care of the correct
3986 -- initialization of nested aggregates bug this is done at the
3987 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
3989 if Can_Never_Be_Null (T) then
3990 if Present (Expression (N))
3991 and then Nkind (Expression (N)) = N_Aggregate
3997 Save_Typ : constant Entity_Id := Etype (Id);
3999 Set_Etype (Id, T); -- Temp. decoration for static checks
4000 Null_Exclusion_Static_Checks (N);
4001 Set_Etype (Id, Save_Typ);
4005 -- We might be dealing with an object of a composite type containing
4006 -- null-excluding components without an aggregate, so we must verify
4007 -- that such components have default initialization.
4010 Check_For_Null_Excluding_Components (T, N);
4014 -- Object is marked pure if it is in a pure scope
4016 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4018 -- If deferred constant, make sure context is appropriate. We detect
4019 -- a deferred constant as a constant declaration with no expression.
4020 -- A deferred constant can appear in a package body if its completion
4021 -- is by means of an interface pragma.
4023 if Constant_Present (N) and then No (E) then
4025 -- A deferred constant may appear in the declarative part of the
4026 -- following constructs:
4030 -- extended return statements
4033 -- subprogram bodies
4036 -- When declared inside a package spec, a deferred constant must be
4037 -- completed by a full constant declaration or pragma Import. In all
4038 -- other cases, the only proper completion is pragma Import. Extended
4039 -- return statements are flagged as invalid contexts because they do
4040 -- not have a declarative part and so cannot accommodate the pragma.
4042 if Ekind (Current_Scope) = E_Return_Statement then
4044 ("invalid context for deferred constant declaration (RM 7.4)",
4047 ("\declaration requires an initialization expression",
4049 Set_Constant_Present (N, False);
4051 -- In Ada 83, deferred constant must be of private type
4053 elsif not Is_Private_Type (T) then
4054 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
4056 ("(Ada 83) deferred constant must be private type", N);
4060 -- If not a deferred constant, then the object declaration freezes
4061 -- its type, unless the object is of an anonymous type and has delayed
4062 -- aspects. In that case the type is frozen when the object itself is.
4065 Check_Fully_Declared (T, N);
4067 if Has_Delayed_Aspects (Id)
4068 and then Is_Array_Type (T)
4069 and then Is_Itype (T)
4071 Set_Has_Delayed_Freeze (T);
4073 Freeze_Before (N, T);
4077 -- If the object was created by a constrained array definition, then
4078 -- set the link in both the anonymous base type and anonymous subtype
4079 -- that are built to represent the array type to point to the object.
4081 if Nkind (Object_Definition (Declaration_Node (Id))) =
4082 N_Constrained_Array_Definition
4084 Set_Related_Array_Object (T, Id);
4085 Set_Related_Array_Object (Base_Type (T), Id);
4088 -- Special checks for protected objects not at library level
4090 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
4091 Check_Restriction (No_Local_Protected_Objects, Id);
4093 -- Protected objects with interrupt handlers must be at library level
4095 -- Ada 2005: This test is not needed (and the corresponding clause
4096 -- in the RM is removed) because accessibility checks are sufficient
4097 -- to make handlers not at the library level illegal.
4099 -- AI05-0303: The AI is in fact a binding interpretation, and thus
4100 -- applies to the '95 version of the language as well.
4102 if Is_Protected_Type (T)
4103 and then Has_Interrupt_Handler (T)
4104 and then Ada_Version < Ada_95
4107 ("interrupt object can only be declared at library level", Id);
4111 -- Check for violation of No_Local_Timing_Events
4113 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
4114 Check_Restriction (No_Local_Timing_Events, Id);
4117 -- The actual subtype of the object is the nominal subtype, unless
4118 -- the nominal one is unconstrained and obtained from the expression.
4122 -- These checks should be performed before the initialization expression
4123 -- is considered, so that the Object_Definition node is still the same
4124 -- as in source code.
4126 -- In SPARK, the nominal subtype is always given by a subtype mark
4127 -- and must not be unconstrained. (The only exception to this is the
4128 -- acceptance of declarations of constants of type String.)
4130 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
4132 Check_SPARK_05_Restriction
4133 ("subtype mark required", Object_Definition (N));
4135 elsif Is_Array_Type (T)
4136 and then not Is_Constrained (T)
4137 and then T /= Standard_String
4139 Check_SPARK_05_Restriction
4140 ("subtype mark of constrained type expected",
4141 Object_Definition (N));
4144 if Is_Library_Level_Entity (Id) then
4145 Check_Dynamic_Object (T);
4148 -- There are no aliased objects in SPARK
4150 if Aliased_Present (N) then
4151 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
4154 -- Process initialization expression if present and not in error
4156 if Present (E) and then E /= Error then
4158 -- Generate an error in case of CPP class-wide object initialization.
4159 -- Required because otherwise the expansion of the class-wide
4160 -- assignment would try to use 'size to initialize the object
4161 -- (primitive that is not available in CPP tagged types).
4163 if Is_Class_Wide_Type (Act_T)
4165 (Is_CPP_Class (Root_Type (Etype (Act_T)))
4167 (Present (Full_View (Root_Type (Etype (Act_T))))
4169 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
4172 ("predefined assignment not available for 'C'P'P tagged types",
4176 Mark_Coextensions (N, E);
4179 -- In case of errors detected in the analysis of the expression,
4180 -- decorate it with the expected type to avoid cascaded errors
4182 if No (Etype (E)) then
4186 -- If an initialization expression is present, then we set the
4187 -- Is_True_Constant flag. It will be reset if this is a variable
4188 -- and it is indeed modified.
4190 Set_Is_True_Constant (Id, True);
4192 -- If we are analyzing a constant declaration, set its completion
4193 -- flag after analyzing and resolving the expression.
4195 if Constant_Present (N) then
4196 Set_Has_Completion (Id);
4199 -- Set type and resolve (type may be overridden later on). Note:
4200 -- Ekind (Id) must still be E_Void at this point so that incorrect
4201 -- early usage within E is properly diagnosed.
4205 -- If the expression is an aggregate we must look ahead to detect
4206 -- the possible presence of an address clause, and defer resolution
4207 -- and expansion of the aggregate to the freeze point of the entity.
4209 -- This is not always legal because the aggregate may contain other
4210 -- references that need freezing, e.g. references to other entities
4211 -- with address clauses. In any case, when compiling with -gnatI the
4212 -- presence of the address clause must be ignored.
4214 if Comes_From_Source (N)
4215 and then Expander_Active
4216 and then Nkind (E) = N_Aggregate
4218 ((Present (Following_Address_Clause (N))
4219 and then not Ignore_Rep_Clauses)
4220 or else Delayed_Aspect_Present)
4228 -- No further action needed if E is a call to an inlined function
4229 -- which returns an unconstrained type and it has been expanded into
4230 -- a procedure call. In that case N has been replaced by an object
4231 -- declaration without initializing expression and it has been
4232 -- analyzed (see Expand_Inlined_Call).
4234 if Back_End_Inlining
4235 and then Expander_Active
4236 and then Nkind (E) = N_Function_Call
4237 and then Nkind (Name (E)) in N_Has_Entity
4238 and then Is_Inlined (Entity (Name (E)))
4239 and then not Is_Constrained (Etype (E))
4240 and then Analyzed (N)
4241 and then No (Expression (N))
4246 -- If E is null and has been replaced by an N_Raise_Constraint_Error
4247 -- node (which was marked already-analyzed), we need to set the type
4248 -- to something other than Any_Access in order to keep gigi happy.
4250 if Etype (E) = Any_Access then
4254 -- If the object is an access to variable, the initialization
4255 -- expression cannot be an access to constant.
4257 if Is_Access_Type (T)
4258 and then not Is_Access_Constant (T)
4259 and then Is_Access_Type (Etype (E))
4260 and then Is_Access_Constant (Etype (E))
4263 ("access to variable cannot be initialized with an "
4264 & "access-to-constant expression", E);
4267 if not Assignment_OK (N) then
4268 Check_Initialization (T, E);
4271 Check_Unset_Reference (E);
4273 -- If this is a variable, then set current value. If this is a
4274 -- declared constant of a scalar type with a static expression,
4275 -- indicate that it is always valid.
4277 if not Constant_Present (N) then
4278 if Compile_Time_Known_Value (E) then
4279 Set_Current_Value (Id, E);
4282 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
4283 Set_Is_Known_Valid (Id);
4286 -- Deal with setting of null flags
4288 if Is_Access_Type (T) then
4289 if Known_Non_Null (E) then
4290 Set_Is_Known_Non_Null (Id, True);
4291 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
4292 Set_Is_Known_Null (Id, True);
4296 -- Check incorrect use of dynamically tagged expressions
4298 if Is_Tagged_Type (T) then
4299 Check_Dynamically_Tagged_Expression
4305 Apply_Scalar_Range_Check (E, T);
4306 Apply_Static_Length_Check (E, T);
4308 if Nkind (Original_Node (N)) = N_Object_Declaration
4309 and then Comes_From_Source (Original_Node (N))
4311 -- Only call test if needed
4313 and then Restriction_Check_Required (SPARK_05)
4314 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
4316 Check_SPARK_05_Restriction
4317 ("initialization expression is not appropriate", E);
4320 -- A formal parameter of a specific tagged type whose related
4321 -- subprogram is subject to pragma Extensions_Visible with value
4322 -- "False" cannot be implicitly converted to a class-wide type by
4323 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
4324 -- not consider internally generated expressions.
4326 if Is_Class_Wide_Type (T)
4327 and then Comes_From_Source (E)
4328 and then Is_EVF_Expression (E)
4331 ("formal parameter cannot be implicitly converted to "
4332 & "class-wide type when Extensions_Visible is False", E);
4336 -- If the No_Streams restriction is set, check that the type of the
4337 -- object is not, and does not contain, any subtype derived from
4338 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
4339 -- Has_Stream just for efficiency reasons. There is no point in
4340 -- spending time on a Has_Stream check if the restriction is not set.
4342 if Restriction_Check_Required (No_Streams) then
4343 if Has_Stream (T) then
4344 Check_Restriction (No_Streams, N);
4348 -- Deal with predicate check before we start to do major rewriting. It
4349 -- is OK to initialize and then check the initialized value, since the
4350 -- object goes out of scope if we get a predicate failure. Note that we
4351 -- do this in the analyzer and not the expander because the analyzer
4352 -- does some substantial rewriting in some cases.
4354 -- We need a predicate check if the type has predicates that are not
4355 -- ignored, and if either there is an initializing expression, or for
4356 -- default initialization when we have at least one case of an explicit
4357 -- default initial value and then this is not an internal declaration
4358 -- whose initialization comes later (as for an aggregate expansion).
4360 if not Suppress_Assignment_Checks (N)
4361 and then Present (Predicate_Function (T))
4362 and then not Predicates_Ignored (T)
4363 and then not No_Initialization (N)
4367 Is_Partially_Initialized_Type (T, Include_Implicit => False))
4369 -- If the type has a static predicate and the expression is known at
4370 -- compile time, see if the expression satisfies the predicate.
4373 Check_Expression_Against_Static_Predicate (E, T);
4376 -- If the type is a null record and there is no explicit initial
4377 -- expression, no predicate check applies.
4379 if No (E) and then Is_Null_Record_Type (T) then
4382 -- Do not generate a predicate check if the initialization expression
4383 -- is a type conversion because the conversion has been subjected to
4384 -- the same check. This is a small optimization which avoid redundant
4387 elsif Present (E) and then Nkind (E) = N_Type_Conversion then
4392 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
4396 -- Case of unconstrained type
4398 if not Is_Definite_Subtype (T) then
4400 -- In SPARK, a declaration of unconstrained type is allowed
4401 -- only for constants of type string.
4403 if Is_String_Type (T) and then not Constant_Present (N) then
4404 Check_SPARK_05_Restriction
4405 ("declaration of object of unconstrained type not allowed", N);
4408 -- Nothing to do in deferred constant case
4410 if Constant_Present (N) and then No (E) then
4413 -- Case of no initialization present
4416 if No_Initialization (N) then
4419 elsif Is_Class_Wide_Type (T) then
4421 ("initialization required in class-wide declaration ", N);
4425 ("unconstrained subtype not allowed (need initialization)",
4426 Object_Definition (N));
4428 if Is_Record_Type (T) and then Has_Discriminants (T) then
4430 ("\provide initial value or explicit discriminant values",
4431 Object_Definition (N));
4434 ("\or give default discriminant values for type&",
4435 Object_Definition (N), T);
4437 elsif Is_Array_Type (T) then
4439 ("\provide initial value or explicit array bounds",
4440 Object_Definition (N));
4444 -- Case of initialization present but in error. Set initial
4445 -- expression as absent (but do not make above complaints)
4447 elsif E = Error then
4448 Set_Expression (N, Empty);
4451 -- Case of initialization present
4454 -- Check restrictions in Ada 83
4456 if not Constant_Present (N) then
4458 -- Unconstrained variables not allowed in Ada 83 mode
4460 if Ada_Version = Ada_83
4461 and then Comes_From_Source (Object_Definition (N))
4464 ("(Ada 83) unconstrained variable not allowed",
4465 Object_Definition (N));
4469 -- Now we constrain the variable from the initializing expression
4471 -- If the expression is an aggregate, it has been expanded into
4472 -- individual assignments. Retrieve the actual type from the
4473 -- expanded construct.
4475 if Is_Array_Type (T)
4476 and then No_Initialization (N)
4477 and then Nkind (Original_Node (E)) = N_Aggregate
4481 -- In case of class-wide interface object declarations we delay
4482 -- the generation of the equivalent record type declarations until
4483 -- its expansion because there are cases in they are not required.
4485 elsif Is_Interface (T) then
4488 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4489 -- we should prevent the generation of another Itype with the
4490 -- same name as the one already generated, or we end up with
4491 -- two identical types in GNATprove.
4493 elsif GNATprove_Mode then
4496 -- If the type is an unchecked union, no subtype can be built from
4497 -- the expression. Rewrite declaration as a renaming, which the
4498 -- back-end can handle properly. This is a rather unusual case,
4499 -- because most unchecked_union declarations have default values
4500 -- for discriminants and are thus not indefinite.
4502 elsif Is_Unchecked_Union (T) then
4503 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4504 Set_Ekind (Id, E_Constant);
4506 Set_Ekind (Id, E_Variable);
4510 Make_Object_Renaming_Declaration (Loc,
4511 Defining_Identifier => Id,
4512 Subtype_Mark => New_Occurrence_Of (T, Loc),
4515 Set_Renamed_Object (Id, E);
4516 Freeze_Before (N, T);
4521 -- Ensure that the generated subtype has a unique external name
4522 -- when the related object is public. This guarantees that the
4523 -- subtype and its bounds will not be affected by switches or
4524 -- pragmas that may offset the internal counter due to extra
4527 if Is_Public (Id) then
4530 Related_Id := Empty;
4533 Expand_Subtype_From_Expr
4536 Subtype_Indic => Object_Definition (N),
4538 Related_Id => Related_Id);
4540 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4543 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4545 if Aliased_Present (N) then
4546 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4549 Freeze_Before (N, Act_T);
4550 Freeze_Before (N, T);
4553 elsif Is_Array_Type (T)
4554 and then No_Initialization (N)
4555 and then (Nkind (Original_Node (E)) = N_Aggregate
4556 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4557 and then Nkind (Original_Node (Expression
4558 (Original_Node (E)))) = N_Aggregate))
4560 if not Is_Entity_Name (Object_Definition (N)) then
4562 Check_Compile_Time_Size (Act_T);
4564 if Aliased_Present (N) then
4565 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4569 -- When the given object definition and the aggregate are specified
4570 -- independently, and their lengths might differ do a length check.
4571 -- This cannot happen if the aggregate is of the form (others =>...)
4573 if not Is_Constrained (T) then
4576 elsif Nkind (E) = N_Raise_Constraint_Error then
4578 -- Aggregate is statically illegal. Place back in declaration
4580 Set_Expression (N, E);
4581 Set_No_Initialization (N, False);
4583 elsif T = Etype (E) then
4586 elsif Nkind (E) = N_Aggregate
4587 and then Present (Component_Associations (E))
4588 and then Present (Choice_List (First (Component_Associations (E))))
4590 Nkind (First (Choice_List (First (Component_Associations (E))))) =
4596 Apply_Length_Check (E, T);
4599 -- If the type is limited unconstrained with defaulted discriminants and
4600 -- there is no expression, then the object is constrained by the
4601 -- defaults, so it is worthwhile building the corresponding subtype.
4603 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4604 and then not Is_Constrained (T)
4605 and then Has_Discriminants (T)
4608 Act_T := Build_Default_Subtype (T, N);
4610 -- Ada 2005: A limited object may be initialized by means of an
4611 -- aggregate. If the type has default discriminants it has an
4612 -- unconstrained nominal type, Its actual subtype will be obtained
4613 -- from the aggregate, and not from the default discriminants.
4618 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4620 elsif Nkind (E) = N_Function_Call
4621 and then Constant_Present (N)
4622 and then Has_Unconstrained_Elements (Etype (E))
4624 -- The back-end has problems with constants of a discriminated type
4625 -- with defaults, if the initial value is a function call. We
4626 -- generate an intermediate temporary that will receive a reference
4627 -- to the result of the call. The initialization expression then
4628 -- becomes a dereference of that temporary.
4630 Remove_Side_Effects (E);
4632 -- If this is a constant declaration of an unconstrained type and
4633 -- the initialization is an aggregate, we can use the subtype of the
4634 -- aggregate for the declared entity because it is immutable.
4636 elsif not Is_Constrained (T)
4637 and then Has_Discriminants (T)
4638 and then Constant_Present (N)
4639 and then not Has_Unchecked_Union (T)
4640 and then Nkind (E) = N_Aggregate
4645 -- Check No_Wide_Characters restriction
4647 Check_Wide_Character_Restriction (T, Object_Definition (N));
4649 -- Indicate this is not set in source. Certainly true for constants, and
4650 -- true for variables so far (will be reset for a variable if and when
4651 -- we encounter a modification in the source).
4653 Set_Never_Set_In_Source (Id);
4655 -- Now establish the proper kind and type of the object
4657 if Constant_Present (N) then
4658 Set_Ekind (Id, E_Constant);
4659 Set_Is_True_Constant (Id);
4662 Set_Ekind (Id, E_Variable);
4664 -- A variable is set as shared passive if it appears in a shared
4665 -- passive package, and is at the outer level. This is not done for
4666 -- entities generated during expansion, because those are always
4667 -- manipulated locally.
4669 if Is_Shared_Passive (Current_Scope)
4670 and then Is_Library_Level_Entity (Id)
4671 and then Comes_From_Source (Id)
4673 Set_Is_Shared_Passive (Id);
4674 Check_Shared_Var (Id, T, N);
4677 -- Set Has_Initial_Value if initializing expression present. Note
4678 -- that if there is no initializing expression, we leave the state
4679 -- of this flag unchanged (usually it will be False, but notably in
4680 -- the case of exception choice variables, it will already be true).
4683 Set_Has_Initial_Value (Id);
4687 -- Initialize alignment and size and capture alignment setting
4689 Init_Alignment (Id);
4691 Set_Optimize_Alignment_Flags (Id);
4693 -- Deal with aliased case
4695 if Aliased_Present (N) then
4696 Set_Is_Aliased (Id);
4698 -- If the object is aliased and the type is unconstrained with
4699 -- defaulted discriminants and there is no expression, then the
4700 -- object is constrained by the defaults, so it is worthwhile
4701 -- building the corresponding subtype.
4703 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4704 -- unconstrained, then only establish an actual subtype if the
4705 -- nominal subtype is indefinite. In definite cases the object is
4706 -- unconstrained in Ada 2005.
4709 and then Is_Record_Type (T)
4710 and then not Is_Constrained (T)
4711 and then Has_Discriminants (T)
4712 and then (Ada_Version < Ada_2005
4713 or else not Is_Definite_Subtype (T))
4715 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4719 -- Now we can set the type of the object
4721 Set_Etype (Id, Act_T);
4723 -- Non-constant object is marked to be treated as volatile if type is
4724 -- volatile and we clear the Current_Value setting that may have been
4725 -- set above. Doing so for constants isn't required and might interfere
4726 -- with possible uses of the object as a static expression in contexts
4727 -- incompatible with volatility (e.g. as a case-statement alternative).
4729 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4730 Set_Treat_As_Volatile (Id);
4731 Set_Current_Value (Id, Empty);
4734 -- Deal with controlled types
4736 if Has_Controlled_Component (Etype (Id))
4737 or else Is_Controlled (Etype (Id))
4739 if not Is_Library_Level_Entity (Id) then
4740 Check_Restriction (No_Nested_Finalization, N);
4742 Validate_Controlled_Object (Id);
4746 if Has_Task (Etype (Id)) then
4747 Check_Restriction (No_Tasking, N);
4749 -- Deal with counting max tasks
4751 -- Nothing to do if inside a generic
4753 if Inside_A_Generic then
4756 -- If library level entity, then count tasks
4758 elsif Is_Library_Level_Entity (Id) then
4759 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4761 -- If not library level entity, then indicate we don't know max
4762 -- tasks and also check task hierarchy restriction and blocking
4763 -- operation (since starting a task is definitely blocking).
4766 Check_Restriction (Max_Tasks, N);
4767 Check_Restriction (No_Task_Hierarchy, N);
4768 Check_Potentially_Blocking_Operation (N);
4771 -- A rather specialized test. If we see two tasks being declared
4772 -- of the same type in the same object declaration, and the task
4773 -- has an entry with an address clause, we know that program error
4774 -- will be raised at run time since we can't have two tasks with
4775 -- entries at the same address.
4777 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4782 E := First_Entity (Etype (Id));
4783 while Present (E) loop
4784 if Ekind (E) = E_Entry
4785 and then Present (Get_Attribute_Definition_Clause
4786 (E, Attribute_Address))
4788 Error_Msg_Warn := SPARK_Mode /= On;
4790 ("more than one task with same entry address<<", N);
4791 Error_Msg_N ("\Program_Error [<<", N);
4793 Make_Raise_Program_Error (Loc,
4794 Reason => PE_Duplicated_Entry_Address));
4804 -- Some simple constant-propagation: if the expression is a constant
4805 -- string initialized with a literal, share the literal. This avoids
4809 and then Is_Entity_Name (E)
4810 and then Ekind (Entity (E)) = E_Constant
4811 and then Base_Type (Etype (E)) = Standard_String
4814 Val : constant Node_Id := Constant_Value (Entity (E));
4816 if Present (Val) and then Nkind (Val) = N_String_Literal then
4817 Rewrite (E, New_Copy (Val));
4822 -- Another optimization: if the nominal subtype is unconstrained and
4823 -- the expression is a function call that returns an unconstrained
4824 -- type, rewrite the declaration as a renaming of the result of the
4825 -- call. The exceptions below are cases where the copy is expected,
4826 -- either by the back end (Aliased case) or by the semantics, as for
4827 -- initializing controlled types or copying tags for class-wide types.
4830 and then Nkind (E) = N_Explicit_Dereference
4831 and then Nkind (Original_Node (E)) = N_Function_Call
4832 and then not Is_Library_Level_Entity (Id)
4833 and then not Is_Constrained (Underlying_Type (T))
4834 and then not Is_Aliased (Id)
4835 and then not Is_Class_Wide_Type (T)
4836 and then not Is_Controlled_Active (T)
4837 and then not Has_Controlled_Component (Base_Type (T))
4838 and then Expander_Active
4841 Make_Object_Renaming_Declaration (Loc,
4842 Defining_Identifier => Id,
4843 Access_Definition => Empty,
4844 Subtype_Mark => New_Occurrence_Of
4845 (Base_Type (Etype (Id)), Loc),
4848 Set_Renamed_Object (Id, E);
4850 -- Force generation of debugging information for the constant and for
4851 -- the renamed function call.
4853 Set_Debug_Info_Needed (Id);
4854 Set_Debug_Info_Needed (Entity (Prefix (E)));
4857 if Present (Prev_Entity)
4858 and then Is_Frozen (Prev_Entity)
4859 and then not Error_Posted (Id)
4861 Error_Msg_N ("full constant declaration appears too late", N);
4864 Check_Eliminated (Id);
4866 -- Deal with setting In_Private_Part flag if in private part
4868 if Ekind (Scope (Id)) = E_Package
4869 and then In_Private_Part (Scope (Id))
4871 Set_In_Private_Part (Id);
4875 -- Initialize the refined state of a variable here because this is a
4876 -- common destination for legal and illegal object declarations.
4878 if Ekind (Id) = E_Variable then
4879 Set_Encapsulating_State (Id, Empty);
4882 if Has_Aspects (N) then
4883 Analyze_Aspect_Specifications (N, Id);
4886 Analyze_Dimension (N);
4888 -- Verify whether the object declaration introduces an illegal hidden
4889 -- state within a package subject to a null abstract state.
4891 if Ekind (Id) = E_Variable then
4892 Check_No_Hidden_State (Id);
4895 Restore_Ghost_Mode (Saved_GM);
4896 end Analyze_Object_Declaration;
4898 ---------------------------
4899 -- Analyze_Others_Choice --
4900 ---------------------------
4902 -- Nothing to do for the others choice node itself, the semantic analysis
4903 -- of the others choice will occur as part of the processing of the parent
4905 procedure Analyze_Others_Choice (N : Node_Id) is
4906 pragma Warnings (Off, N);
4909 end Analyze_Others_Choice;
4911 -------------------------------------------
4912 -- Analyze_Private_Extension_Declaration --
4913 -------------------------------------------
4915 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4916 Indic : constant Node_Id := Subtype_Indication (N);
4917 T : constant Entity_Id := Defining_Identifier (N);
4919 Iface_Elmt : Elmt_Id;
4920 Parent_Base : Entity_Id;
4921 Parent_Type : Entity_Id;
4924 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4926 if Is_Non_Empty_List (Interface_List (N)) then
4932 Intf := First (Interface_List (N));
4933 while Present (Intf) loop
4934 T := Find_Type_Of_Subtype_Indic (Intf);
4936 Diagnose_Interface (Intf, T);
4942 Generate_Definition (T);
4944 -- For other than Ada 2012, just enter the name in the current scope
4946 if Ada_Version < Ada_2012 then
4949 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4950 -- case of private type that completes an incomplete type.
4957 Prev := Find_Type_Name (N);
4959 pragma Assert (Prev = T
4960 or else (Ekind (Prev) = E_Incomplete_Type
4961 and then Present (Full_View (Prev))
4962 and then Full_View (Prev) = T));
4966 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4967 Parent_Base := Base_Type (Parent_Type);
4969 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4970 Set_Ekind (T, Ekind (Parent_Type));
4971 Set_Etype (T, Any_Type);
4974 elsif not Is_Tagged_Type (Parent_Type) then
4976 ("parent of type extension must be a tagged type ", Indic);
4979 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4980 Error_Msg_N ("premature derivation of incomplete type", Indic);
4983 elsif Is_Concurrent_Type (Parent_Type) then
4985 ("parent type of a private extension cannot be a synchronized "
4986 & "tagged type (RM 3.9.1 (3/1))", N);
4988 Set_Etype (T, Any_Type);
4989 Set_Ekind (T, E_Limited_Private_Type);
4990 Set_Private_Dependents (T, New_Elmt_List);
4991 Set_Error_Posted (T);
4995 -- Perhaps the parent type should be changed to the class-wide type's
4996 -- specific type in this case to prevent cascading errors ???
4998 if Is_Class_Wide_Type (Parent_Type) then
5000 ("parent of type extension must not be a class-wide type", Indic);
5004 if (not Is_Package_Or_Generic_Package (Current_Scope)
5005 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
5006 or else In_Private_Part (Current_Scope)
5008 Error_Msg_N ("invalid context for private extension", N);
5011 -- Set common attributes
5013 Set_Is_Pure (T, Is_Pure (Current_Scope));
5014 Set_Scope (T, Current_Scope);
5015 Set_Ekind (T, E_Record_Type_With_Private);
5016 Init_Size_Align (T);
5017 Set_Default_SSO (T);
5018 Set_No_Reordering (T, No_Component_Reordering);
5020 Set_Etype (T, Parent_Base);
5021 Propagate_Concurrent_Flags (T, Parent_Base);
5023 Set_Convention (T, Convention (Parent_Type));
5024 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
5025 Set_Is_First_Subtype (T);
5026 Make_Class_Wide_Type (T);
5028 if Unknown_Discriminants_Present (N) then
5029 Set_Discriminant_Constraint (T, No_Elist);
5032 Build_Derived_Record_Type (N, Parent_Type, T);
5034 -- A private extension inherits the Default_Initial_Condition pragma
5035 -- coming from any parent type within the derivation chain.
5037 if Has_DIC (Parent_Type) then
5038 Set_Has_Inherited_DIC (T);
5041 -- A private extension inherits any class-wide invariants coming from a
5042 -- parent type or an interface. Note that the invariant procedure of the
5043 -- parent type should not be inherited because the private extension may
5044 -- define invariants of its own.
5046 if Has_Inherited_Invariants (Parent_Type)
5047 or else Has_Inheritable_Invariants (Parent_Type)
5049 Set_Has_Inherited_Invariants (T);
5051 elsif Present (Interfaces (T)) then
5052 Iface_Elmt := First_Elmt (Interfaces (T));
5053 while Present (Iface_Elmt) loop
5054 Iface := Node (Iface_Elmt);
5056 if Has_Inheritable_Invariants (Iface) then
5057 Set_Has_Inherited_Invariants (T);
5061 Next_Elmt (Iface_Elmt);
5065 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
5066 -- synchronized formal derived type.
5068 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
5069 Set_Is_Limited_Record (T);
5071 -- Formal derived type case
5073 if Is_Generic_Type (T) then
5075 -- The parent must be a tagged limited type or a synchronized
5078 if (not Is_Tagged_Type (Parent_Type)
5079 or else not Is_Limited_Type (Parent_Type))
5081 (not Is_Interface (Parent_Type)
5082 or else not Is_Synchronized_Interface (Parent_Type))
5085 ("parent type of & must be tagged limited or synchronized",
5089 -- The progenitors (if any) must be limited or synchronized
5092 if Present (Interfaces (T)) then
5093 Iface_Elmt := First_Elmt (Interfaces (T));
5094 while Present (Iface_Elmt) loop
5095 Iface := Node (Iface_Elmt);
5097 if not Is_Limited_Interface (Iface)
5098 and then not Is_Synchronized_Interface (Iface)
5101 ("progenitor & must be limited or synchronized",
5105 Next_Elmt (Iface_Elmt);
5109 -- Regular derived extension, the parent must be a limited or
5110 -- synchronized interface.
5113 if not Is_Interface (Parent_Type)
5114 or else (not Is_Limited_Interface (Parent_Type)
5115 and then not Is_Synchronized_Interface (Parent_Type))
5118 ("parent type of & must be limited interface", N, T);
5122 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
5123 -- extension with a synchronized parent must be explicitly declared
5124 -- synchronized, because the full view will be a synchronized type.
5125 -- This must be checked before the check for limited types below,
5126 -- to ensure that types declared limited are not allowed to extend
5127 -- synchronized interfaces.
5129 elsif Is_Interface (Parent_Type)
5130 and then Is_Synchronized_Interface (Parent_Type)
5131 and then not Synchronized_Present (N)
5134 ("private extension of& must be explicitly synchronized",
5137 elsif Limited_Present (N) then
5138 Set_Is_Limited_Record (T);
5140 if not Is_Limited_Type (Parent_Type)
5142 (not Is_Interface (Parent_Type)
5143 or else not Is_Limited_Interface (Parent_Type))
5145 Error_Msg_NE ("parent type& of limited extension must be limited",
5150 -- Remember that its parent type has a private extension. Used to warn
5151 -- on public primitives of the parent type defined after its private
5152 -- extensions (see Check_Dispatching_Operation).
5154 Set_Has_Private_Extension (Parent_Type);
5157 if Has_Aspects (N) then
5158 Analyze_Aspect_Specifications (N, T);
5160 end Analyze_Private_Extension_Declaration;
5162 ---------------------------------
5163 -- Analyze_Subtype_Declaration --
5164 ---------------------------------
5166 procedure Analyze_Subtype_Declaration
5168 Skip : Boolean := False)
5170 Id : constant Entity_Id := Defining_Identifier (N);
5171 R_Checks : Check_Result;
5175 Generate_Definition (Id);
5176 Set_Is_Pure (Id, Is_Pure (Current_Scope));
5177 Init_Size_Align (Id);
5179 -- The following guard condition on Enter_Name is to handle cases where
5180 -- the defining identifier has already been entered into the scope but
5181 -- the declaration as a whole needs to be analyzed.
5183 -- This case in particular happens for derived enumeration types. The
5184 -- derived enumeration type is processed as an inserted enumeration type
5185 -- declaration followed by a rewritten subtype declaration. The defining
5186 -- identifier, however, is entered into the name scope very early in the
5187 -- processing of the original type declaration and therefore needs to be
5188 -- avoided here, when the created subtype declaration is analyzed. (See
5189 -- Build_Derived_Types)
5191 -- This also happens when the full view of a private type is derived
5192 -- type with constraints. In this case the entity has been introduced
5193 -- in the private declaration.
5195 -- Finally this happens in some complex cases when validity checks are
5196 -- enabled, where the same subtype declaration may be analyzed twice.
5197 -- This can happen if the subtype is created by the pre-analysis of
5198 -- an attribute tht gives the range of a loop statement, and the loop
5199 -- itself appears within an if_statement that will be rewritten during
5203 or else (Present (Etype (Id))
5204 and then (Is_Private_Type (Etype (Id))
5205 or else Is_Task_Type (Etype (Id))
5206 or else Is_Rewrite_Substitution (N)))
5210 elsif Current_Entity (Id) = Id then
5217 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
5219 -- Class-wide equivalent types of records with unknown discriminants
5220 -- involve the generation of an itype which serves as the private view
5221 -- of a constrained record subtype. In such cases the base type of the
5222 -- current subtype we are processing is the private itype. Use the full
5223 -- of the private itype when decorating various attributes.
5226 and then Is_Private_Type (T)
5227 and then Present (Full_View (T))
5232 -- Inherit common attributes
5234 Set_Is_Volatile (Id, Is_Volatile (T));
5235 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
5236 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
5237 Set_Convention (Id, Convention (T));
5239 -- If ancestor has predicates then so does the subtype, and in addition
5240 -- we must delay the freeze to properly arrange predicate inheritance.
5242 -- The Ancestor_Type test is really unpleasant, there seem to be cases
5243 -- in which T = ID, so the above tests and assignments do nothing???
5245 if Has_Predicates (T)
5246 or else (Present (Ancestor_Subtype (T))
5247 and then Has_Predicates (Ancestor_Subtype (T)))
5249 Set_Has_Predicates (Id);
5250 Set_Has_Delayed_Freeze (Id);
5252 -- Generated subtypes inherit the predicate function from the parent
5253 -- (no aspects to examine on the generated declaration).
5255 if not Comes_From_Source (N) then
5256 Set_Ekind (Id, Ekind (T));
5258 if Present (Predicate_Function (T)) then
5259 Set_Predicate_Function (Id, Predicate_Function (T));
5261 elsif Present (Ancestor_Subtype (T))
5262 and then Has_Predicates (Ancestor_Subtype (T))
5263 and then Present (Predicate_Function (Ancestor_Subtype (T)))
5265 Set_Predicate_Function (Id,
5266 Predicate_Function (Ancestor_Subtype (T)));
5271 -- Subtype of Boolean cannot have a constraint in SPARK
5273 if Is_Boolean_Type (T)
5274 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
5276 Check_SPARK_05_Restriction
5277 ("subtype of Boolean cannot have constraint", N);
5280 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5282 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5288 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
5289 One_Cstr := First (Constraints (Cstr));
5290 while Present (One_Cstr) loop
5292 -- Index or discriminant constraint in SPARK must be a
5296 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
5298 Check_SPARK_05_Restriction
5299 ("subtype mark required", One_Cstr);
5301 -- String subtype must have a lower bound of 1 in SPARK.
5302 -- Note that we do not need to test for the non-static case
5303 -- here, since that was already taken care of in
5304 -- Process_Range_Expr_In_Decl.
5306 elsif Base_Type (T) = Standard_String then
5307 Get_Index_Bounds (One_Cstr, Low, High);
5309 if Is_OK_Static_Expression (Low)
5310 and then Expr_Value (Low) /= 1
5312 Check_SPARK_05_Restriction
5313 ("String subtype must have lower bound of 1", N);
5323 -- In the case where there is no constraint given in the subtype
5324 -- indication, Process_Subtype just returns the Subtype_Mark, so its
5325 -- semantic attributes must be established here.
5327 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
5328 Set_Etype (Id, Base_Type (T));
5330 -- Subtype of unconstrained array without constraint is not allowed
5333 if Is_Array_Type (T) and then not Is_Constrained (T) then
5334 Check_SPARK_05_Restriction
5335 ("subtype of unconstrained array must have constraint", N);
5340 Set_Ekind (Id, E_Array_Subtype);
5341 Copy_Array_Subtype_Attributes (Id, T);
5343 when Decimal_Fixed_Point_Kind =>
5344 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
5345 Set_Digits_Value (Id, Digits_Value (T));
5346 Set_Delta_Value (Id, Delta_Value (T));
5347 Set_Scale_Value (Id, Scale_Value (T));
5348 Set_Small_Value (Id, Small_Value (T));
5349 Set_Scalar_Range (Id, Scalar_Range (T));
5350 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
5351 Set_Is_Constrained (Id, Is_Constrained (T));
5352 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5353 Set_RM_Size (Id, RM_Size (T));
5355 when Enumeration_Kind =>
5356 Set_Ekind (Id, E_Enumeration_Subtype);
5357 Set_First_Literal (Id, First_Literal (Base_Type (T)));
5358 Set_Scalar_Range (Id, Scalar_Range (T));
5359 Set_Is_Character_Type (Id, Is_Character_Type (T));
5360 Set_Is_Constrained (Id, Is_Constrained (T));
5361 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5362 Set_RM_Size (Id, RM_Size (T));
5363 Inherit_Predicate_Flags (Id, T);
5365 when Ordinary_Fixed_Point_Kind =>
5366 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
5367 Set_Scalar_Range (Id, Scalar_Range (T));
5368 Set_Small_Value (Id, Small_Value (T));
5369 Set_Delta_Value (Id, Delta_Value (T));
5370 Set_Is_Constrained (Id, Is_Constrained (T));
5371 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5372 Set_RM_Size (Id, RM_Size (T));
5375 Set_Ekind (Id, E_Floating_Point_Subtype);
5376 Set_Scalar_Range (Id, Scalar_Range (T));
5377 Set_Digits_Value (Id, Digits_Value (T));
5378 Set_Is_Constrained (Id, Is_Constrained (T));
5380 -- If the floating point type has dimensions, these will be
5381 -- inherited subsequently when Analyze_Dimensions is called.
5383 when Signed_Integer_Kind =>
5384 Set_Ekind (Id, E_Signed_Integer_Subtype);
5385 Set_Scalar_Range (Id, Scalar_Range (T));
5386 Set_Is_Constrained (Id, Is_Constrained (T));
5387 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5388 Set_RM_Size (Id, RM_Size (T));
5389 Inherit_Predicate_Flags (Id, T);
5391 when Modular_Integer_Kind =>
5392 Set_Ekind (Id, E_Modular_Integer_Subtype);
5393 Set_Scalar_Range (Id, Scalar_Range (T));
5394 Set_Is_Constrained (Id, Is_Constrained (T));
5395 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5396 Set_RM_Size (Id, RM_Size (T));
5397 Inherit_Predicate_Flags (Id, T);
5399 when Class_Wide_Kind =>
5400 Set_Ekind (Id, E_Class_Wide_Subtype);
5401 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5402 Set_Cloned_Subtype (Id, T);
5403 Set_Is_Tagged_Type (Id, True);
5404 Set_Has_Unknown_Discriminants
5406 Set_No_Tagged_Streams_Pragma
5407 (Id, No_Tagged_Streams_Pragma (T));
5409 if Ekind (T) = E_Class_Wide_Subtype then
5410 Set_Equivalent_Type (Id, Equivalent_Type (T));
5413 when E_Record_Subtype
5416 Set_Ekind (Id, E_Record_Subtype);
5418 if Ekind (T) = E_Record_Subtype
5419 and then Present (Cloned_Subtype (T))
5421 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5423 Set_Cloned_Subtype (Id, T);
5426 Set_First_Entity (Id, First_Entity (T));
5427 Set_Last_Entity (Id, Last_Entity (T));
5428 Set_Has_Discriminants (Id, Has_Discriminants (T));
5429 Set_Is_Constrained (Id, Is_Constrained (T));
5430 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5431 Set_Has_Implicit_Dereference
5432 (Id, Has_Implicit_Dereference (T));
5433 Set_Has_Unknown_Discriminants
5434 (Id, Has_Unknown_Discriminants (T));
5436 if Has_Discriminants (T) then
5437 Set_Discriminant_Constraint
5438 (Id, Discriminant_Constraint (T));
5439 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5441 elsif Has_Unknown_Discriminants (Id) then
5442 Set_Discriminant_Constraint (Id, No_Elist);
5445 if Is_Tagged_Type (T) then
5446 Set_Is_Tagged_Type (Id, True);
5447 Set_No_Tagged_Streams_Pragma
5448 (Id, No_Tagged_Streams_Pragma (T));
5449 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5450 Set_Direct_Primitive_Operations
5451 (Id, Direct_Primitive_Operations (T));
5452 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5454 if Is_Interface (T) then
5455 Set_Is_Interface (Id);
5456 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5460 when Private_Kind =>
5461 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5462 Set_Has_Discriminants (Id, Has_Discriminants (T));
5463 Set_Is_Constrained (Id, Is_Constrained (T));
5464 Set_First_Entity (Id, First_Entity (T));
5465 Set_Last_Entity (Id, Last_Entity (T));
5466 Set_Private_Dependents (Id, New_Elmt_List);
5467 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5468 Set_Has_Implicit_Dereference
5469 (Id, Has_Implicit_Dereference (T));
5470 Set_Has_Unknown_Discriminants
5471 (Id, Has_Unknown_Discriminants (T));
5472 Set_Known_To_Have_Preelab_Init
5473 (Id, Known_To_Have_Preelab_Init (T));
5475 if Is_Tagged_Type (T) then
5476 Set_Is_Tagged_Type (Id);
5477 Set_No_Tagged_Streams_Pragma (Id,
5478 No_Tagged_Streams_Pragma (T));
5479 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5480 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5481 Set_Direct_Primitive_Operations (Id,
5482 Direct_Primitive_Operations (T));
5485 -- In general the attributes of the subtype of a private type
5486 -- are the attributes of the partial view of parent. However,
5487 -- the full view may be a discriminated type, and the subtype
5488 -- must share the discriminant constraint to generate correct
5489 -- calls to initialization procedures.
5491 if Has_Discriminants (T) then
5492 Set_Discriminant_Constraint
5493 (Id, Discriminant_Constraint (T));
5494 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5496 elsif Present (Full_View (T))
5497 and then Has_Discriminants (Full_View (T))
5499 Set_Discriminant_Constraint
5500 (Id, Discriminant_Constraint (Full_View (T)));
5501 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5503 -- This would seem semantically correct, but apparently
5504 -- generates spurious errors about missing components ???
5506 -- Set_Has_Discriminants (Id);
5509 Prepare_Private_Subtype_Completion (Id, N);
5511 -- If this is the subtype of a constrained private type with
5512 -- discriminants that has got a full view and we also have
5513 -- built a completion just above, show that the completion
5514 -- is a clone of the full view to the back-end.
5516 if Has_Discriminants (T)
5517 and then not Has_Unknown_Discriminants (T)
5518 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5519 and then Present (Full_View (T))
5520 and then Present (Full_View (Id))
5522 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5526 Set_Ekind (Id, E_Access_Subtype);
5527 Set_Is_Constrained (Id, Is_Constrained (T));
5528 Set_Is_Access_Constant
5529 (Id, Is_Access_Constant (T));
5530 Set_Directly_Designated_Type
5531 (Id, Designated_Type (T));
5532 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5534 -- A Pure library_item must not contain the declaration of a
5535 -- named access type, except within a subprogram, generic
5536 -- subprogram, task unit, or protected unit, or if it has
5537 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5539 if Comes_From_Source (Id)
5540 and then In_Pure_Unit
5541 and then not In_Subprogram_Task_Protected_Unit
5542 and then not No_Pool_Assigned (Id)
5545 ("named access types not allowed in pure unit", N);
5548 when Concurrent_Kind =>
5549 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5550 Set_Corresponding_Record_Type (Id,
5551 Corresponding_Record_Type (T));
5552 Set_First_Entity (Id, First_Entity (T));
5553 Set_First_Private_Entity (Id, First_Private_Entity (T));
5554 Set_Has_Discriminants (Id, Has_Discriminants (T));
5555 Set_Is_Constrained (Id, Is_Constrained (T));
5556 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5557 Set_Last_Entity (Id, Last_Entity (T));
5559 if Is_Tagged_Type (T) then
5560 Set_No_Tagged_Streams_Pragma
5561 (Id, No_Tagged_Streams_Pragma (T));
5564 if Has_Discriminants (T) then
5565 Set_Discriminant_Constraint
5566 (Id, Discriminant_Constraint (T));
5567 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5570 when Incomplete_Kind =>
5571 if Ada_Version >= Ada_2005 then
5573 -- In Ada 2005 an incomplete type can be explicitly tagged:
5574 -- propagate indication. Note that we also have to include
5575 -- subtypes for Ada 2012 extended use of incomplete types.
5577 Set_Ekind (Id, E_Incomplete_Subtype);
5578 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5579 Set_Private_Dependents (Id, New_Elmt_List);
5581 if Is_Tagged_Type (Id) then
5582 Set_No_Tagged_Streams_Pragma
5583 (Id, No_Tagged_Streams_Pragma (T));
5584 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5587 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5588 -- incomplete type visible through a limited with clause.
5590 if From_Limited_With (T)
5591 and then Present (Non_Limited_View (T))
5593 Set_From_Limited_With (Id);
5594 Set_Non_Limited_View (Id, Non_Limited_View (T));
5596 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5597 -- to the private dependents of the original incomplete
5598 -- type for future transformation.
5601 Append_Elmt (Id, Private_Dependents (T));
5604 -- If the subtype name denotes an incomplete type an error
5605 -- was already reported by Process_Subtype.
5608 Set_Etype (Id, Any_Type);
5612 raise Program_Error;
5616 if Etype (Id) = Any_Type then
5620 -- Some common processing on all types
5622 Set_Size_Info (Id, T);
5623 Set_First_Rep_Item (Id, First_Rep_Item (T));
5625 -- If the parent type is a generic actual, so is the subtype. This may
5626 -- happen in a nested instance. Why Comes_From_Source test???
5628 if not Comes_From_Source (N) then
5629 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5632 -- If this is a subtype declaration for an actual in an instance,
5633 -- inherit static and dynamic predicates if any.
5635 -- If declaration has no aspect specifications, inherit predicate
5636 -- info as well. Unclear how to handle the case of both specified
5637 -- and inherited predicates ??? Other inherited aspects, such as
5638 -- invariants, should be OK, but the combination with later pragmas
5639 -- may also require special merging.
5641 if Has_Predicates (T)
5642 and then Present (Predicate_Function (T))
5644 ((In_Instance and then not Comes_From_Source (N))
5645 or else No (Aspect_Specifications (N)))
5647 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5649 if Has_Static_Predicate (T) then
5650 Set_Has_Static_Predicate (Id);
5651 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5655 -- Remaining processing depends on characteristics of base type
5659 Set_Is_Immediately_Visible (Id, True);
5660 Set_Depends_On_Private (Id, Has_Private_Component (T));
5661 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5663 if Is_Interface (T) then
5664 Set_Is_Interface (Id);
5667 if Present (Generic_Parent_Type (N))
5669 (Nkind (Parent (Generic_Parent_Type (N))) /=
5670 N_Formal_Type_Declaration
5671 or else Nkind (Formal_Type_Definition
5672 (Parent (Generic_Parent_Type (N)))) /=
5673 N_Formal_Private_Type_Definition)
5675 if Is_Tagged_Type (Id) then
5677 -- If this is a generic actual subtype for a synchronized type,
5678 -- the primitive operations are those of the corresponding record
5679 -- for which there is a separate subtype declaration.
5681 if Is_Concurrent_Type (Id) then
5683 elsif Is_Class_Wide_Type (Id) then
5684 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5686 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5689 elsif Scope (Etype (Id)) /= Standard_Standard then
5690 Derive_Subprograms (Generic_Parent_Type (N), Id);
5694 if Is_Private_Type (T) and then Present (Full_View (T)) then
5695 Conditional_Delay (Id, Full_View (T));
5697 -- The subtypes of components or subcomponents of protected types
5698 -- do not need freeze nodes, which would otherwise appear in the
5699 -- wrong scope (before the freeze node for the protected type). The
5700 -- proper subtypes are those of the subcomponents of the corresponding
5703 elsif Ekind (Scope (Id)) /= E_Protected_Type
5704 and then Present (Scope (Scope (Id))) -- error defense
5705 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5707 Conditional_Delay (Id, T);
5710 -- Check that Constraint_Error is raised for a scalar subtype indication
5711 -- when the lower or upper bound of a non-null range lies outside the
5712 -- range of the type mark.
5714 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5715 if Is_Scalar_Type (Etype (Id))
5716 and then Scalar_Range (Id) /=
5718 (Etype (Subtype_Mark (Subtype_Indication (N))))
5722 Etype (Subtype_Mark (Subtype_Indication (N))));
5724 -- In the array case, check compatibility for each index
5726 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5728 -- This really should be a subprogram that finds the indications
5732 Subt_Index : Node_Id := First_Index (Id);
5733 Target_Index : Node_Id :=
5735 (Subtype_Mark (Subtype_Indication (N))));
5736 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5739 while Present (Subt_Index) loop
5740 if ((Nkind (Subt_Index) = N_Identifier
5741 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5742 or else Nkind (Subt_Index) = N_Subtype_Indication)
5744 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5747 Target_Typ : constant Entity_Id :=
5748 Etype (Target_Index);
5752 (Scalar_Range (Etype (Subt_Index)),
5755 Defining_Identifier (N));
5757 -- Reset Has_Dynamic_Range_Check on the subtype to
5758 -- prevent elision of the index check due to a dynamic
5759 -- check generated for a preceding index (needed since
5760 -- Insert_Range_Checks tries to avoid generating
5761 -- redundant checks on a given declaration).
5763 Set_Has_Dynamic_Range_Check (N, False);
5769 Sloc (Defining_Identifier (N)));
5771 -- Record whether this index involved a dynamic check
5774 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5778 Next_Index (Subt_Index);
5779 Next_Index (Target_Index);
5782 -- Finally, mark whether the subtype involves dynamic checks
5784 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5789 Set_Optimize_Alignment_Flags (Id);
5790 Check_Eliminated (Id);
5793 if Has_Aspects (N) then
5794 Analyze_Aspect_Specifications (N, Id);
5797 Analyze_Dimension (N);
5799 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5800 -- indications on composite types where the constraints are dynamic.
5801 -- Note that object declarations and aggregates generate implicit
5802 -- subtype declarations, which this covers. One special case is that the
5803 -- implicitly generated "=" for discriminated types includes an
5804 -- offending subtype declaration, which is harmless, so we ignore it
5807 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5809 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5811 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5812 and then not (Is_Internal (Id)
5813 and then Is_TSS (Scope (Id),
5814 TSS_Composite_Equality))
5815 and then not Within_Init_Proc
5816 and then not All_Composite_Constraints_Static (Cstr)
5818 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5822 end Analyze_Subtype_Declaration;
5824 --------------------------------
5825 -- Analyze_Subtype_Indication --
5826 --------------------------------
5828 procedure Analyze_Subtype_Indication (N : Node_Id) is
5829 T : constant Entity_Id := Subtype_Mark (N);
5830 R : constant Node_Id := Range_Expression (Constraint (N));
5837 Set_Etype (N, Etype (R));
5838 Resolve (R, Entity (T));
5840 Set_Error_Posted (R);
5841 Set_Error_Posted (T);
5843 end Analyze_Subtype_Indication;
5845 --------------------------
5846 -- Analyze_Variant_Part --
5847 --------------------------
5849 procedure Analyze_Variant_Part (N : Node_Id) is
5850 Discr_Name : Node_Id;
5851 Discr_Type : Entity_Id;
5853 procedure Process_Variant (A : Node_Id);
5854 -- Analyze declarations for a single variant
5856 package Analyze_Variant_Choices is
5857 new Generic_Analyze_Choices (Process_Variant);
5858 use Analyze_Variant_Choices;
5860 ---------------------
5861 -- Process_Variant --
5862 ---------------------
5864 procedure Process_Variant (A : Node_Id) is
5865 CL : constant Node_Id := Component_List (A);
5867 if not Null_Present (CL) then
5868 Analyze_Declarations (Component_Items (CL));
5870 if Present (Variant_Part (CL)) then
5871 Analyze (Variant_Part (CL));
5874 end Process_Variant;
5876 -- Start of processing for Analyze_Variant_Part
5879 Discr_Name := Name (N);
5880 Analyze (Discr_Name);
5882 -- If Discr_Name bad, get out (prevent cascaded errors)
5884 if Etype (Discr_Name) = Any_Type then
5888 -- Check invalid discriminant in variant part
5890 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5891 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5894 Discr_Type := Etype (Entity (Discr_Name));
5896 if not Is_Discrete_Type (Discr_Type) then
5898 ("discriminant in a variant part must be of a discrete type",
5903 -- Now analyze the choices, which also analyzes the declarations that
5904 -- are associated with each choice.
5906 Analyze_Choices (Variants (N), Discr_Type);
5908 -- Note: we used to instantiate and call Check_Choices here to check
5909 -- that the choices covered the discriminant, but it's too early to do
5910 -- that because of statically predicated subtypes, whose analysis may
5911 -- be deferred to their freeze point which may be as late as the freeze
5912 -- point of the containing record. So this call is now to be found in
5913 -- Freeze_Record_Declaration.
5915 end Analyze_Variant_Part;
5917 ----------------------------
5918 -- Array_Type_Declaration --
5919 ----------------------------
5921 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5922 Component_Def : constant Node_Id := Component_Definition (Def);
5923 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5924 P : constant Node_Id := Parent (Def);
5925 Element_Type : Entity_Id;
5926 Implicit_Base : Entity_Id;
5930 Related_Id : Entity_Id := Empty;
5933 if Nkind (Def) = N_Constrained_Array_Definition then
5934 Index := First (Discrete_Subtype_Definitions (Def));
5936 Index := First (Subtype_Marks (Def));
5939 -- Find proper names for the implicit types which may be public. In case
5940 -- of anonymous arrays we use the name of the first object of that type
5944 Related_Id := Defining_Identifier (P);
5950 while Present (Index) loop
5953 -- Test for odd case of trying to index a type by the type itself
5955 if Is_Entity_Name (Index) and then Entity (Index) = T then
5956 Error_Msg_N ("type& cannot be indexed by itself", Index);
5957 Set_Entity (Index, Standard_Boolean);
5958 Set_Etype (Index, Standard_Boolean);
5961 -- Check SPARK restriction requiring a subtype mark
5963 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5964 Check_SPARK_05_Restriction ("subtype mark required", Index);
5967 -- Add a subtype declaration for each index of private array type
5968 -- declaration whose etype is also private. For example:
5971 -- type Index is private;
5973 -- type Table is array (Index) of ...
5976 -- This is currently required by the expander for the internally
5977 -- generated equality subprogram of records with variant parts in
5978 -- which the etype of some component is such private type.
5980 if Ekind (Current_Scope) = E_Package
5981 and then In_Private_Part (Current_Scope)
5982 and then Has_Private_Declaration (Etype (Index))
5985 Loc : constant Source_Ptr := Sloc (Def);
5990 New_E := Make_Temporary (Loc, 'T');
5991 Set_Is_Internal (New_E);
5994 Make_Subtype_Declaration (Loc,
5995 Defining_Identifier => New_E,
5996 Subtype_Indication =>
5997 New_Occurrence_Of (Etype (Index), Loc));
5999 Insert_Before (Parent (Def), Decl);
6001 Set_Etype (Index, New_E);
6003 -- If the index is a range the Entity attribute is not
6004 -- available. Example:
6007 -- type T is private;
6009 -- type T is new Natural;
6010 -- Table : array (T(1) .. T(10)) of Boolean;
6013 if Nkind (Index) /= N_Range then
6014 Set_Entity (Index, New_E);
6019 Make_Index (Index, P, Related_Id, Nb_Index);
6021 -- Check error of subtype with predicate for index type
6023 Bad_Predicated_Subtype_Use
6024 ("subtype& has predicate, not allowed as index subtype",
6025 Index, Etype (Index));
6027 -- Move to next index
6030 Nb_Index := Nb_Index + 1;
6033 -- Process subtype indication if one is present
6035 if Present (Component_Typ) then
6036 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
6038 Set_Etype (Component_Typ, Element_Type);
6040 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
6041 Check_SPARK_05_Restriction
6042 ("subtype mark required", Component_Typ);
6045 -- Ada 2005 (AI-230): Access Definition case
6047 else pragma Assert (Present (Access_Definition (Component_Def)));
6049 -- Indicate that the anonymous access type is created by the
6050 -- array type declaration.
6052 Element_Type := Access_Definition
6054 N => Access_Definition (Component_Def));
6055 Set_Is_Local_Anonymous_Access (Element_Type);
6057 -- Propagate the parent. This field is needed if we have to generate
6058 -- the master_id associated with an anonymous access to task type
6059 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
6061 Set_Parent (Element_Type, Parent (T));
6063 -- Ada 2005 (AI-230): In case of components that are anonymous access
6064 -- types the level of accessibility depends on the enclosing type
6067 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
6069 -- Ada 2005 (AI-254)
6072 CD : constant Node_Id :=
6073 Access_To_Subprogram_Definition
6074 (Access_Definition (Component_Def));
6076 if Present (CD) and then Protected_Present (CD) then
6078 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
6083 -- Constrained array case
6086 T := Create_Itype (E_Void, P, Related_Id, 'T');
6089 if Nkind (Def) = N_Constrained_Array_Definition then
6091 -- Establish Implicit_Base as unconstrained base type
6093 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
6095 Set_Etype (Implicit_Base, Implicit_Base);
6096 Set_Scope (Implicit_Base, Current_Scope);
6097 Set_Has_Delayed_Freeze (Implicit_Base);
6098 Set_Default_SSO (Implicit_Base);
6100 -- The constrained array type is a subtype of the unconstrained one
6102 Set_Ekind (T, E_Array_Subtype);
6103 Init_Size_Align (T);
6104 Set_Etype (T, Implicit_Base);
6105 Set_Scope (T, Current_Scope);
6106 Set_Is_Constrained (T);
6108 First (Discrete_Subtype_Definitions (Def)));
6109 Set_Has_Delayed_Freeze (T);
6111 -- Complete setup of implicit base type
6113 Set_Component_Size (Implicit_Base, Uint_0);
6114 Set_Component_Type (Implicit_Base, Element_Type);
6115 Set_Finalize_Storage_Only
6117 Finalize_Storage_Only (Element_Type));
6118 Set_First_Index (Implicit_Base, First_Index (T));
6119 Set_Has_Controlled_Component
6121 Has_Controlled_Component (Element_Type)
6122 or else Is_Controlled_Active (Element_Type));
6123 Set_Packed_Array_Impl_Type
6124 (Implicit_Base, Empty);
6126 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
6128 -- Unconstrained array case
6131 Set_Ekind (T, E_Array_Type);
6132 Init_Size_Align (T);
6134 Set_Scope (T, Current_Scope);
6135 Set_Component_Size (T, Uint_0);
6136 Set_Is_Constrained (T, False);
6137 Set_First_Index (T, First (Subtype_Marks (Def)));
6138 Set_Has_Delayed_Freeze (T, True);
6139 Propagate_Concurrent_Flags (T, Element_Type);
6140 Set_Has_Controlled_Component (T, Has_Controlled_Component
6143 Is_Controlled_Active (Element_Type));
6144 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
6146 Set_Default_SSO (T);
6149 -- Common attributes for both cases
6151 Set_Component_Type (Base_Type (T), Element_Type);
6152 Set_Packed_Array_Impl_Type (T, Empty);
6154 if Aliased_Present (Component_Definition (Def)) then
6155 Check_SPARK_05_Restriction
6156 ("aliased is not allowed", Component_Definition (Def));
6157 Set_Has_Aliased_Components (Etype (T));
6160 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
6161 -- array type to ensure that objects of this type are initialized.
6163 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
6164 Set_Can_Never_Be_Null (T);
6166 if Null_Exclusion_Present (Component_Definition (Def))
6168 -- No need to check itypes because in their case this check was
6169 -- done at their point of creation
6171 and then not Is_Itype (Element_Type)
6174 ("`NOT NULL` not allowed (null already excluded)",
6175 Subtype_Indication (Component_Definition (Def)));
6179 Priv := Private_Component (Element_Type);
6181 if Present (Priv) then
6183 -- Check for circular definitions
6185 if Priv = Any_Type then
6186 Set_Component_Type (Etype (T), Any_Type);
6188 -- There is a gap in the visibility of operations on the composite
6189 -- type only if the component type is defined in a different scope.
6191 elsif Scope (Priv) = Current_Scope then
6194 elsif Is_Limited_Type (Priv) then
6195 Set_Is_Limited_Composite (Etype (T));
6196 Set_Is_Limited_Composite (T);
6198 Set_Is_Private_Composite (Etype (T));
6199 Set_Is_Private_Composite (T);
6203 -- A syntax error in the declaration itself may lead to an empty index
6204 -- list, in which case do a minimal patch.
6206 if No (First_Index (T)) then
6207 Error_Msg_N ("missing index definition in array type declaration", T);
6210 Indexes : constant List_Id :=
6211 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
6213 Set_Discrete_Subtype_Definitions (Def, Indexes);
6214 Set_First_Index (T, First (Indexes));
6219 -- Create a concatenation operator for the new type. Internal array
6220 -- types created for packed entities do not need such, they are
6221 -- compatible with the user-defined type.
6223 if Number_Dimensions (T) = 1
6224 and then not Is_Packed_Array_Impl_Type (T)
6226 New_Concatenation_Op (T);
6229 -- In the case of an unconstrained array the parser has already verified
6230 -- that all the indexes are unconstrained but we still need to make sure
6231 -- that the element type is constrained.
6233 if not Is_Definite_Subtype (Element_Type) then
6235 ("unconstrained element type in array declaration",
6236 Subtype_Indication (Component_Def));
6238 elsif Is_Abstract_Type (Element_Type) then
6240 ("the type of a component cannot be abstract",
6241 Subtype_Indication (Component_Def));
6244 -- There may be an invariant declared for the component type, but
6245 -- the construction of the component invariant checking procedure
6246 -- takes place during expansion.
6247 end Array_Type_Declaration;
6249 ------------------------------------------------------
6250 -- Replace_Anonymous_Access_To_Protected_Subprogram --
6251 ------------------------------------------------------
6253 function Replace_Anonymous_Access_To_Protected_Subprogram
6254 (N : Node_Id) return Entity_Id
6256 Loc : constant Source_Ptr := Sloc (N);
6258 Curr_Scope : constant Scope_Stack_Entry :=
6259 Scope_Stack.Table (Scope_Stack.Last);
6261 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
6264 -- Access definition in declaration
6267 -- Object definition or formal definition with an access definition
6270 -- Declaration of anonymous access to subprogram type
6273 -- Original specification in access to subprogram
6278 Set_Is_Internal (Anon);
6281 when N_Constrained_Array_Definition
6282 | N_Component_Declaration
6283 | N_Unconstrained_Array_Definition
6285 Comp := Component_Definition (N);
6286 Acc := Access_Definition (Comp);
6288 when N_Discriminant_Specification =>
6289 Comp := Discriminant_Type (N);
6292 when N_Parameter_Specification =>
6293 Comp := Parameter_Type (N);
6296 when N_Access_Function_Definition =>
6297 Comp := Result_Definition (N);
6300 when N_Object_Declaration =>
6301 Comp := Object_Definition (N);
6304 when N_Function_Specification =>
6305 Comp := Result_Definition (N);
6309 raise Program_Error;
6312 Spec := Access_To_Subprogram_Definition (Acc);
6315 Make_Full_Type_Declaration (Loc,
6316 Defining_Identifier => Anon,
6317 Type_Definition => Copy_Separate_Tree (Spec));
6319 Mark_Rewrite_Insertion (Decl);
6321 -- In ASIS mode, analyze the profile on the original node, because
6322 -- the separate copy does not provide enough links to recover the
6323 -- original tree. Analysis is limited to type annotations, within
6324 -- a temporary scope that serves as an anonymous subprogram to collect
6325 -- otherwise useless temporaries and itypes.
6329 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
6332 if Nkind (Spec) = N_Access_Function_Definition then
6333 Set_Ekind (Typ, E_Function);
6335 Set_Ekind (Typ, E_Procedure);
6338 Set_Parent (Typ, N);
6339 Set_Scope (Typ, Current_Scope);
6342 -- Nothing to do if procedure is parameterless
6344 if Present (Parameter_Specifications (Spec)) then
6345 Process_Formals (Parameter_Specifications (Spec), Spec);
6348 if Nkind (Spec) = N_Access_Function_Definition then
6350 Def : constant Node_Id := Result_Definition (Spec);
6353 -- The result might itself be an anonymous access type, so
6356 if Nkind (Def) = N_Access_Definition then
6357 if Present (Access_To_Subprogram_Definition (Def)) then
6360 Replace_Anonymous_Access_To_Protected_Subprogram
6363 Find_Type (Subtype_Mark (Def));
6376 -- Insert the new declaration in the nearest enclosing scope. If the
6377 -- parent is a body and N is its return type, the declaration belongs
6378 -- in the enclosing scope. Likewise if N is the type of a parameter.
6382 if Nkind (N) = N_Function_Specification
6383 and then Nkind (P) = N_Subprogram_Body
6386 elsif Nkind (N) = N_Parameter_Specification
6387 and then Nkind (P) in N_Subprogram_Specification
6388 and then Nkind (Parent (P)) = N_Subprogram_Body
6390 P := Parent (Parent (P));
6393 while Present (P) and then not Has_Declarations (P) loop
6397 pragma Assert (Present (P));
6399 if Nkind (P) = N_Package_Specification then
6400 Prepend (Decl, Visible_Declarations (P));
6402 Prepend (Decl, Declarations (P));
6405 -- Replace the anonymous type with an occurrence of the new declaration.
6406 -- In all cases the rewritten node does not have the null-exclusion
6407 -- attribute because (if present) it was already inherited by the
6408 -- anonymous entity (Anon). Thus, in case of components we do not
6409 -- inherit this attribute.
6411 if Nkind (N) = N_Parameter_Specification then
6412 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6413 Set_Etype (Defining_Identifier (N), Anon);
6414 Set_Null_Exclusion_Present (N, False);
6416 elsif Nkind (N) = N_Object_Declaration then
6417 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6418 Set_Etype (Defining_Identifier (N), Anon);
6420 elsif Nkind (N) = N_Access_Function_Definition then
6421 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6423 elsif Nkind (N) = N_Function_Specification then
6424 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6425 Set_Etype (Defining_Unit_Name (N), Anon);
6429 Make_Component_Definition (Loc,
6430 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6433 Mark_Rewrite_Insertion (Comp);
6435 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6436 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6437 and then not Is_Type (Current_Scope))
6440 -- Declaration can be analyzed in the current scope.
6445 -- Temporarily remove the current scope (record or subprogram) from
6446 -- the stack to add the new declarations to the enclosing scope.
6447 -- The anonymous entity is an Itype with the proper attributes.
6449 Scope_Stack.Decrement_Last;
6451 Set_Is_Itype (Anon);
6452 Set_Associated_Node_For_Itype (Anon, N);
6453 Scope_Stack.Append (Curr_Scope);
6456 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6457 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6459 end Replace_Anonymous_Access_To_Protected_Subprogram;
6461 -------------------------------
6462 -- Build_Derived_Access_Type --
6463 -------------------------------
6465 procedure Build_Derived_Access_Type
6467 Parent_Type : Entity_Id;
6468 Derived_Type : Entity_Id)
6470 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6472 Desig_Type : Entity_Id;
6474 Discr_Con_Elist : Elist_Id;
6475 Discr_Con_El : Elmt_Id;
6479 -- Set the designated type so it is available in case this is an access
6480 -- to a self-referential type, e.g. a standard list type with a next
6481 -- pointer. Will be reset after subtype is built.
6483 Set_Directly_Designated_Type
6484 (Derived_Type, Designated_Type (Parent_Type));
6486 Subt := Process_Subtype (S, N);
6488 if Nkind (S) /= N_Subtype_Indication
6489 and then Subt /= Base_Type (Subt)
6491 Set_Ekind (Derived_Type, E_Access_Subtype);
6494 if Ekind (Derived_Type) = E_Access_Subtype then
6496 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6497 Ibase : constant Entity_Id :=
6498 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6499 Svg_Chars : constant Name_Id := Chars (Ibase);
6500 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6503 Copy_Node (Pbase, Ibase);
6505 -- Restore Itype status after Copy_Node
6507 Set_Is_Itype (Ibase);
6508 Set_Associated_Node_For_Itype (Ibase, N);
6510 Set_Chars (Ibase, Svg_Chars);
6511 Set_Next_Entity (Ibase, Svg_Next_E);
6512 Set_Sloc (Ibase, Sloc (Derived_Type));
6513 Set_Scope (Ibase, Scope (Derived_Type));
6514 Set_Freeze_Node (Ibase, Empty);
6515 Set_Is_Frozen (Ibase, False);
6516 Set_Comes_From_Source (Ibase, False);
6517 Set_Is_First_Subtype (Ibase, False);
6519 Set_Etype (Ibase, Pbase);
6520 Set_Etype (Derived_Type, Ibase);
6524 Set_Directly_Designated_Type
6525 (Derived_Type, Designated_Type (Subt));
6527 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6528 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6529 Set_Size_Info (Derived_Type, Parent_Type);
6530 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6531 Set_Depends_On_Private (Derived_Type,
6532 Has_Private_Component (Derived_Type));
6533 Conditional_Delay (Derived_Type, Subt);
6535 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6536 -- that it is not redundant.
6538 if Null_Exclusion_Present (Type_Definition (N)) then
6539 Set_Can_Never_Be_Null (Derived_Type);
6541 elsif Can_Never_Be_Null (Parent_Type) then
6542 Set_Can_Never_Be_Null (Derived_Type);
6545 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6546 -- the root type for this information.
6548 -- Apply range checks to discriminants for derived record case
6549 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6551 Desig_Type := Designated_Type (Derived_Type);
6553 if Is_Composite_Type (Desig_Type)
6554 and then (not Is_Array_Type (Desig_Type))
6555 and then Has_Discriminants (Desig_Type)
6556 and then Base_Type (Desig_Type) /= Desig_Type
6558 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6559 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6561 Discr := First_Discriminant (Base_Type (Desig_Type));
6562 while Present (Discr_Con_El) loop
6563 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6564 Next_Elmt (Discr_Con_El);
6565 Next_Discriminant (Discr);
6568 end Build_Derived_Access_Type;
6570 ------------------------------
6571 -- Build_Derived_Array_Type --
6572 ------------------------------
6574 procedure Build_Derived_Array_Type
6576 Parent_Type : Entity_Id;
6577 Derived_Type : Entity_Id)
6579 Loc : constant Source_Ptr := Sloc (N);
6580 Tdef : constant Node_Id := Type_Definition (N);
6581 Indic : constant Node_Id := Subtype_Indication (Tdef);
6582 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6583 Implicit_Base : Entity_Id;
6584 New_Indic : Node_Id;
6586 procedure Make_Implicit_Base;
6587 -- If the parent subtype is constrained, the derived type is a subtype
6588 -- of an implicit base type derived from the parent base.
6590 ------------------------
6591 -- Make_Implicit_Base --
6592 ------------------------
6594 procedure Make_Implicit_Base is
6597 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6599 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6600 Set_Etype (Implicit_Base, Parent_Base);
6602 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6603 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6605 Set_Has_Delayed_Freeze (Implicit_Base, True);
6606 end Make_Implicit_Base;
6608 -- Start of processing for Build_Derived_Array_Type
6611 if not Is_Constrained (Parent_Type) then
6612 if Nkind (Indic) /= N_Subtype_Indication then
6613 Set_Ekind (Derived_Type, E_Array_Type);
6615 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6616 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6618 Set_Has_Delayed_Freeze (Derived_Type, True);
6622 Set_Etype (Derived_Type, Implicit_Base);
6625 Make_Subtype_Declaration (Loc,
6626 Defining_Identifier => Derived_Type,
6627 Subtype_Indication =>
6628 Make_Subtype_Indication (Loc,
6629 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6630 Constraint => Constraint (Indic)));
6632 Rewrite (N, New_Indic);
6637 if Nkind (Indic) /= N_Subtype_Indication then
6640 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6641 Set_Etype (Derived_Type, Implicit_Base);
6642 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6645 Error_Msg_N ("illegal constraint on constrained type", Indic);
6649 -- If parent type is not a derived type itself, and is declared in
6650 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6651 -- the new type's concatenation operator since Derive_Subprograms
6652 -- will not inherit the parent's operator. If the parent type is
6653 -- unconstrained, the operator is of the unconstrained base type.
6655 if Number_Dimensions (Parent_Type) = 1
6656 and then not Is_Limited_Type (Parent_Type)
6657 and then not Is_Derived_Type (Parent_Type)
6658 and then not Is_Package_Or_Generic_Package
6659 (Scope (Base_Type (Parent_Type)))
6661 if not Is_Constrained (Parent_Type)
6662 and then Is_Constrained (Derived_Type)
6664 New_Concatenation_Op (Implicit_Base);
6666 New_Concatenation_Op (Derived_Type);
6669 end Build_Derived_Array_Type;
6671 -----------------------------------
6672 -- Build_Derived_Concurrent_Type --
6673 -----------------------------------
6675 procedure Build_Derived_Concurrent_Type
6677 Parent_Type : Entity_Id;
6678 Derived_Type : Entity_Id)
6680 Loc : constant Source_Ptr := Sloc (N);
6682 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6683 Corr_Decl : Node_Id;
6684 Corr_Decl_Needed : Boolean;
6685 -- If the derived type has fewer discriminants than its parent, the
6686 -- corresponding record is also a derived type, in order to account for
6687 -- the bound discriminants. We create a full type declaration for it in
6690 Constraint_Present : constant Boolean :=
6691 Nkind (Subtype_Indication (Type_Definition (N))) =
6692 N_Subtype_Indication;
6694 D_Constraint : Node_Id;
6695 New_Constraint : Elist_Id;
6696 Old_Disc : Entity_Id;
6697 New_Disc : Entity_Id;
6701 Set_Stored_Constraint (Derived_Type, No_Elist);
6702 Corr_Decl_Needed := False;
6705 if Present (Discriminant_Specifications (N))
6706 and then Constraint_Present
6708 Old_Disc := First_Discriminant (Parent_Type);
6709 New_Disc := First (Discriminant_Specifications (N));
6710 while Present (New_Disc) and then Present (Old_Disc) loop
6711 Next_Discriminant (Old_Disc);
6716 if Present (Old_Disc) and then Expander_Active then
6718 -- The new type has fewer discriminants, so we need to create a new
6719 -- corresponding record, which is derived from the corresponding
6720 -- record of the parent, and has a stored constraint that captures
6721 -- the values of the discriminant constraints. The corresponding
6722 -- record is needed only if expander is active and code generation is
6725 -- The type declaration for the derived corresponding record has the
6726 -- same discriminant part and constraints as the current declaration.
6727 -- Copy the unanalyzed tree to build declaration.
6729 Corr_Decl_Needed := True;
6730 New_N := Copy_Separate_Tree (N);
6733 Make_Full_Type_Declaration (Loc,
6734 Defining_Identifier => Corr_Record,
6735 Discriminant_Specifications =>
6736 Discriminant_Specifications (New_N),
6738 Make_Derived_Type_Definition (Loc,
6739 Subtype_Indication =>
6740 Make_Subtype_Indication (Loc,
6743 (Corresponding_Record_Type (Parent_Type), Loc),
6746 (Subtype_Indication (Type_Definition (New_N))))));
6749 -- Copy Storage_Size and Relative_Deadline variables if task case
6751 if Is_Task_Type (Parent_Type) then
6752 Set_Storage_Size_Variable (Derived_Type,
6753 Storage_Size_Variable (Parent_Type));
6754 Set_Relative_Deadline_Variable (Derived_Type,
6755 Relative_Deadline_Variable (Parent_Type));
6758 if Present (Discriminant_Specifications (N)) then
6759 Push_Scope (Derived_Type);
6760 Check_Or_Process_Discriminants (N, Derived_Type);
6762 if Constraint_Present then
6764 Expand_To_Stored_Constraint
6766 Build_Discriminant_Constraints
6768 Subtype_Indication (Type_Definition (N)), True));
6773 elsif Constraint_Present then
6775 -- Build constrained subtype, copying the constraint, and derive
6776 -- from it to create a derived constrained type.
6779 Loc : constant Source_Ptr := Sloc (N);
6780 Anon : constant Entity_Id :=
6781 Make_Defining_Identifier (Loc,
6782 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6787 Make_Subtype_Declaration (Loc,
6788 Defining_Identifier => Anon,
6789 Subtype_Indication =>
6790 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6791 Insert_Before (N, Decl);
6794 Rewrite (Subtype_Indication (Type_Definition (N)),
6795 New_Occurrence_Of (Anon, Loc));
6796 Set_Analyzed (Derived_Type, False);
6802 -- By default, operations and private data are inherited from parent.
6803 -- However, in the presence of bound discriminants, a new corresponding
6804 -- record will be created, see below.
6806 Set_Has_Discriminants
6807 (Derived_Type, Has_Discriminants (Parent_Type));
6808 Set_Corresponding_Record_Type
6809 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6811 -- Is_Constrained is set according the parent subtype, but is set to
6812 -- False if the derived type is declared with new discriminants.
6816 (Is_Constrained (Parent_Type) or else Constraint_Present)
6817 and then not Present (Discriminant_Specifications (N)));
6819 if Constraint_Present then
6820 if not Has_Discriminants (Parent_Type) then
6821 Error_Msg_N ("untagged parent must have discriminants", N);
6823 elsif Present (Discriminant_Specifications (N)) then
6825 -- Verify that new discriminants are used to constrain old ones
6830 (Constraint (Subtype_Indication (Type_Definition (N)))));
6832 Old_Disc := First_Discriminant (Parent_Type);
6834 while Present (D_Constraint) loop
6835 if Nkind (D_Constraint) /= N_Discriminant_Association then
6837 -- Positional constraint. If it is a reference to a new
6838 -- discriminant, it constrains the corresponding old one.
6840 if Nkind (D_Constraint) = N_Identifier then
6841 New_Disc := First_Discriminant (Derived_Type);
6842 while Present (New_Disc) loop
6843 exit when Chars (New_Disc) = Chars (D_Constraint);
6844 Next_Discriminant (New_Disc);
6847 if Present (New_Disc) then
6848 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6852 Next_Discriminant (Old_Disc);
6854 -- if this is a named constraint, search by name for the old
6855 -- discriminants constrained by the new one.
6857 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6859 -- Find new discriminant with that name
6861 New_Disc := First_Discriminant (Derived_Type);
6862 while Present (New_Disc) loop
6864 Chars (New_Disc) = Chars (Expression (D_Constraint));
6865 Next_Discriminant (New_Disc);
6868 if Present (New_Disc) then
6870 -- Verify that new discriminant renames some discriminant
6871 -- of the parent type, and associate the new discriminant
6872 -- with one or more old ones that it renames.
6878 Selector := First (Selector_Names (D_Constraint));
6879 while Present (Selector) loop
6880 Old_Disc := First_Discriminant (Parent_Type);
6881 while Present (Old_Disc) loop
6882 exit when Chars (Old_Disc) = Chars (Selector);
6883 Next_Discriminant (Old_Disc);
6886 if Present (Old_Disc) then
6887 Set_Corresponding_Discriminant
6888 (New_Disc, Old_Disc);
6897 Next (D_Constraint);
6900 New_Disc := First_Discriminant (Derived_Type);
6901 while Present (New_Disc) loop
6902 if No (Corresponding_Discriminant (New_Disc)) then
6904 ("new discriminant& must constrain old one", N, New_Disc);
6907 Subtypes_Statically_Compatible
6909 Etype (Corresponding_Discriminant (New_Disc)))
6912 ("& not statically compatible with parent discriminant",
6916 Next_Discriminant (New_Disc);
6920 elsif Present (Discriminant_Specifications (N)) then
6922 ("missing discriminant constraint in untagged derivation", N);
6925 -- The entity chain of the derived type includes the new discriminants
6926 -- but shares operations with the parent.
6928 if Present (Discriminant_Specifications (N)) then
6929 Old_Disc := First_Discriminant (Parent_Type);
6930 while Present (Old_Disc) loop
6931 if No (Next_Entity (Old_Disc))
6932 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6935 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6939 Next_Discriminant (Old_Disc);
6943 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6944 if Has_Discriminants (Parent_Type) then
6945 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6946 Set_Discriminant_Constraint (
6947 Derived_Type, Discriminant_Constraint (Parent_Type));
6951 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6953 Set_Has_Completion (Derived_Type);
6955 if Corr_Decl_Needed then
6956 Set_Stored_Constraint (Derived_Type, New_Constraint);
6957 Insert_After (N, Corr_Decl);
6958 Analyze (Corr_Decl);
6959 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6961 end Build_Derived_Concurrent_Type;
6963 ------------------------------------
6964 -- Build_Derived_Enumeration_Type --
6965 ------------------------------------
6967 procedure Build_Derived_Enumeration_Type
6969 Parent_Type : Entity_Id;
6970 Derived_Type : Entity_Id)
6972 Loc : constant Source_Ptr := Sloc (N);
6973 Def : constant Node_Id := Type_Definition (N);
6974 Indic : constant Node_Id := Subtype_Indication (Def);
6975 Implicit_Base : Entity_Id;
6976 Literal : Entity_Id;
6977 New_Lit : Entity_Id;
6978 Literals_List : List_Id;
6979 Type_Decl : Node_Id;
6981 Rang_Expr : Node_Id;
6984 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6985 -- not have explicit literals lists we need to process types derived
6986 -- from them specially. This is handled by Derived_Standard_Character.
6987 -- If the parent type is a generic type, there are no literals either,
6988 -- and we construct the same skeletal representation as for the generic
6991 if Is_Standard_Character_Type (Parent_Type) then
6992 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6994 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
7000 if Nkind (Indic) /= N_Subtype_Indication then
7002 Make_Attribute_Reference (Loc,
7003 Attribute_Name => Name_First,
7004 Prefix => New_Occurrence_Of (Derived_Type, Loc));
7005 Set_Etype (Lo, Derived_Type);
7008 Make_Attribute_Reference (Loc,
7009 Attribute_Name => Name_Last,
7010 Prefix => New_Occurrence_Of (Derived_Type, Loc));
7011 Set_Etype (Hi, Derived_Type);
7013 Set_Scalar_Range (Derived_Type,
7019 -- Analyze subtype indication and verify compatibility
7020 -- with parent type.
7022 if Base_Type (Process_Subtype (Indic, N)) /=
7023 Base_Type (Parent_Type)
7026 ("illegal constraint for formal discrete type", N);
7032 -- If a constraint is present, analyze the bounds to catch
7033 -- premature usage of the derived literals.
7035 if Nkind (Indic) = N_Subtype_Indication
7036 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
7038 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
7039 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
7042 -- Introduce an implicit base type for the derived type even if there
7043 -- is no constraint attached to it, since this seems closer to the
7044 -- Ada semantics. Build a full type declaration tree for the derived
7045 -- type using the implicit base type as the defining identifier. The
7046 -- build a subtype declaration tree which applies the constraint (if
7047 -- any) have it replace the derived type declaration.
7049 Literal := First_Literal (Parent_Type);
7050 Literals_List := New_List;
7051 while Present (Literal)
7052 and then Ekind (Literal) = E_Enumeration_Literal
7054 -- Literals of the derived type have the same representation as
7055 -- those of the parent type, but this representation can be
7056 -- overridden by an explicit representation clause. Indicate
7057 -- that there is no explicit representation given yet. These
7058 -- derived literals are implicit operations of the new type,
7059 -- and can be overridden by explicit ones.
7061 if Nkind (Literal) = N_Defining_Character_Literal then
7063 Make_Defining_Character_Literal (Loc, Chars (Literal));
7065 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
7068 Set_Ekind (New_Lit, E_Enumeration_Literal);
7069 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
7070 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
7071 Set_Enumeration_Rep_Expr (New_Lit, Empty);
7072 Set_Alias (New_Lit, Literal);
7073 Set_Is_Known_Valid (New_Lit, True);
7075 Append (New_Lit, Literals_List);
7076 Next_Literal (Literal);
7080 Make_Defining_Identifier (Sloc (Derived_Type),
7081 Chars => New_External_Name (Chars (Derived_Type), 'B'));
7083 -- Indicate the proper nature of the derived type. This must be done
7084 -- before analysis of the literals, to recognize cases when a literal
7085 -- may be hidden by a previous explicit function definition (cf.
7088 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
7089 Set_Etype (Derived_Type, Implicit_Base);
7092 Make_Full_Type_Declaration (Loc,
7093 Defining_Identifier => Implicit_Base,
7094 Discriminant_Specifications => No_List,
7096 Make_Enumeration_Type_Definition (Loc, Literals_List));
7098 Mark_Rewrite_Insertion (Type_Decl);
7099 Insert_Before (N, Type_Decl);
7100 Analyze (Type_Decl);
7102 -- The anonymous base now has a full declaration, but this base
7103 -- is not a first subtype.
7105 Set_Is_First_Subtype (Implicit_Base, False);
7107 -- After the implicit base is analyzed its Etype needs to be changed
7108 -- to reflect the fact that it is derived from the parent type which
7109 -- was ignored during analysis. We also set the size at this point.
7111 Set_Etype (Implicit_Base, Parent_Type);
7113 Set_Size_Info (Implicit_Base, Parent_Type);
7114 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
7115 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
7117 -- Copy other flags from parent type
7119 Set_Has_Non_Standard_Rep
7120 (Implicit_Base, Has_Non_Standard_Rep
7122 Set_Has_Pragma_Ordered
7123 (Implicit_Base, Has_Pragma_Ordered
7125 Set_Has_Delayed_Freeze (Implicit_Base);
7127 -- Process the subtype indication including a validation check on the
7128 -- constraint, if any. If a constraint is given, its bounds must be
7129 -- implicitly converted to the new type.
7131 if Nkind (Indic) = N_Subtype_Indication then
7133 R : constant Node_Id :=
7134 Range_Expression (Constraint (Indic));
7137 if Nkind (R) = N_Range then
7138 Hi := Build_Scalar_Bound
7139 (High_Bound (R), Parent_Type, Implicit_Base);
7140 Lo := Build_Scalar_Bound
7141 (Low_Bound (R), Parent_Type, Implicit_Base);
7144 -- Constraint is a Range attribute. Replace with explicit
7145 -- mention of the bounds of the prefix, which must be a
7148 Analyze (Prefix (R));
7150 Convert_To (Implicit_Base,
7151 Make_Attribute_Reference (Loc,
7152 Attribute_Name => Name_Last,
7154 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
7157 Convert_To (Implicit_Base,
7158 Make_Attribute_Reference (Loc,
7159 Attribute_Name => Name_First,
7161 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
7168 (Type_High_Bound (Parent_Type),
7169 Parent_Type, Implicit_Base);
7172 (Type_Low_Bound (Parent_Type),
7173 Parent_Type, Implicit_Base);
7181 -- If we constructed a default range for the case where no range
7182 -- was given, then the expressions in the range must not freeze
7183 -- since they do not correspond to expressions in the source.
7184 -- However, if the type inherits predicates the expressions will
7185 -- be elaborated earlier and must freeze.
7187 if Nkind (Indic) /= N_Subtype_Indication
7188 and then not Has_Predicates (Derived_Type)
7190 Set_Must_Not_Freeze (Lo);
7191 Set_Must_Not_Freeze (Hi);
7192 Set_Must_Not_Freeze (Rang_Expr);
7196 Make_Subtype_Declaration (Loc,
7197 Defining_Identifier => Derived_Type,
7198 Subtype_Indication =>
7199 Make_Subtype_Indication (Loc,
7200 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
7202 Make_Range_Constraint (Loc,
7203 Range_Expression => Rang_Expr))));
7207 -- Propagate the aspects from the original type declaration to the
7208 -- declaration of the implicit base.
7210 Move_Aspects (From => Original_Node (N), To => Type_Decl);
7212 -- Apply a range check. Since this range expression doesn't have an
7213 -- Etype, we have to specifically pass the Source_Typ parameter. Is
7216 if Nkind (Indic) = N_Subtype_Indication then
7218 (Range_Expression (Constraint (Indic)), Parent_Type,
7219 Source_Typ => Entity (Subtype_Mark (Indic)));
7222 end Build_Derived_Enumeration_Type;
7224 --------------------------------
7225 -- Build_Derived_Numeric_Type --
7226 --------------------------------
7228 procedure Build_Derived_Numeric_Type
7230 Parent_Type : Entity_Id;
7231 Derived_Type : Entity_Id)
7233 Loc : constant Source_Ptr := Sloc (N);
7234 Tdef : constant Node_Id := Type_Definition (N);
7235 Indic : constant Node_Id := Subtype_Indication (Tdef);
7236 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7237 No_Constraint : constant Boolean := Nkind (Indic) /=
7238 N_Subtype_Indication;
7239 Implicit_Base : Entity_Id;
7245 -- Process the subtype indication including a validation check on
7246 -- the constraint if any.
7248 Discard_Node (Process_Subtype (Indic, N));
7250 -- Introduce an implicit base type for the derived type even if there
7251 -- is no constraint attached to it, since this seems closer to the Ada
7255 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
7257 Set_Etype (Implicit_Base, Parent_Base);
7258 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
7259 Set_Size_Info (Implicit_Base, Parent_Base);
7260 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
7261 Set_Parent (Implicit_Base, Parent (Derived_Type));
7262 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
7264 -- Set RM Size for discrete type or decimal fixed-point type
7265 -- Ordinary fixed-point is excluded, why???
7267 if Is_Discrete_Type (Parent_Base)
7268 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
7270 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
7273 Set_Has_Delayed_Freeze (Implicit_Base);
7275 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
7276 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
7278 Set_Scalar_Range (Implicit_Base,
7283 if Has_Infinities (Parent_Base) then
7284 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
7287 -- The Derived_Type, which is the entity of the declaration, is a
7288 -- subtype of the implicit base. Its Ekind is a subtype, even in the
7289 -- absence of an explicit constraint.
7291 Set_Etype (Derived_Type, Implicit_Base);
7293 -- If we did not have a constraint, then the Ekind is set from the
7294 -- parent type (otherwise Process_Subtype has set the bounds)
7296 if No_Constraint then
7297 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
7300 -- If we did not have a range constraint, then set the range from the
7301 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
7303 if No_Constraint or else not Has_Range_Constraint (Indic) then
7304 Set_Scalar_Range (Derived_Type,
7306 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
7307 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
7308 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7310 if Has_Infinities (Parent_Type) then
7311 Set_Includes_Infinities (Scalar_Range (Derived_Type));
7314 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
7317 Set_Is_Descendant_Of_Address (Derived_Type,
7318 Is_Descendant_Of_Address (Parent_Type));
7319 Set_Is_Descendant_Of_Address (Implicit_Base,
7320 Is_Descendant_Of_Address (Parent_Type));
7322 -- Set remaining type-specific fields, depending on numeric type
7324 if Is_Modular_Integer_Type (Parent_Type) then
7325 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
7327 Set_Non_Binary_Modulus
7328 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
7331 (Implicit_Base, Is_Known_Valid (Parent_Base));
7333 elsif Is_Floating_Point_Type (Parent_Type) then
7335 -- Digits of base type is always copied from the digits value of
7336 -- the parent base type, but the digits of the derived type will
7337 -- already have been set if there was a constraint present.
7339 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7340 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
7342 if No_Constraint then
7343 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
7346 elsif Is_Fixed_Point_Type (Parent_Type) then
7348 -- Small of base type and derived type are always copied from the
7349 -- parent base type, since smalls never change. The delta of the
7350 -- base type is also copied from the parent base type. However the
7351 -- delta of the derived type will have been set already if a
7352 -- constraint was present.
7354 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
7355 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
7356 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
7358 if No_Constraint then
7359 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
7362 -- The scale and machine radix in the decimal case are always
7363 -- copied from the parent base type.
7365 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
7366 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
7367 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
7369 Set_Machine_Radix_10
7370 (Derived_Type, Machine_Radix_10 (Parent_Base));
7371 Set_Machine_Radix_10
7372 (Implicit_Base, Machine_Radix_10 (Parent_Base));
7374 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7376 if No_Constraint then
7377 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
7380 -- the analysis of the subtype_indication sets the
7381 -- digits value of the derived type.
7388 if Is_Integer_Type (Parent_Type) then
7389 Set_Has_Shift_Operator
7390 (Implicit_Base, Has_Shift_Operator (Parent_Type));
7393 -- The type of the bounds is that of the parent type, and they
7394 -- must be converted to the derived type.
7396 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
7398 -- The implicit_base should be frozen when the derived type is frozen,
7399 -- but note that it is used in the conversions of the bounds. For fixed
7400 -- types we delay the determination of the bounds until the proper
7401 -- freezing point. For other numeric types this is rejected by GCC, for
7402 -- reasons that are currently unclear (???), so we choose to freeze the
7403 -- implicit base now. In the case of integers and floating point types
7404 -- this is harmless because subsequent representation clauses cannot
7405 -- affect anything, but it is still baffling that we cannot use the
7406 -- same mechanism for all derived numeric types.
7408 -- There is a further complication: actually some representation
7409 -- clauses can affect the implicit base type. For example, attribute
7410 -- definition clauses for stream-oriented attributes need to set the
7411 -- corresponding TSS entries on the base type, and this normally
7412 -- cannot be done after the base type is frozen, so the circuitry in
7413 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
7414 -- and not use Set_TSS in this case.
7416 -- There are also consequences for the case of delayed representation
7417 -- aspects for some cases. For example, a Size aspect is delayed and
7418 -- should not be evaluated to the freeze point. This early freezing
7419 -- means that the size attribute evaluation happens too early???
7421 if Is_Fixed_Point_Type (Parent_Type) then
7422 Conditional_Delay (Implicit_Base, Parent_Type);
7424 Freeze_Before (N, Implicit_Base);
7426 end Build_Derived_Numeric_Type;
7428 --------------------------------
7429 -- Build_Derived_Private_Type --
7430 --------------------------------
7432 procedure Build_Derived_Private_Type
7434 Parent_Type : Entity_Id;
7435 Derived_Type : Entity_Id;
7436 Is_Completion : Boolean;
7437 Derive_Subps : Boolean := True)
7439 Loc : constant Source_Ptr := Sloc (N);
7440 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7441 Par_Scope : constant Entity_Id := Scope (Par_Base);
7442 Full_N : constant Node_Id := New_Copy_Tree (N);
7443 Full_Der : Entity_Id := New_Copy (Derived_Type);
7446 procedure Build_Full_Derivation;
7447 -- Build full derivation, i.e. derive from the full view
7449 procedure Copy_And_Build;
7450 -- Copy derived type declaration, replace parent with its full view,
7451 -- and build derivation
7453 ---------------------------
7454 -- Build_Full_Derivation --
7455 ---------------------------
7457 procedure Build_Full_Derivation is
7459 -- If parent scope is not open, install the declarations
7461 if not In_Open_Scopes (Par_Scope) then
7462 Install_Private_Declarations (Par_Scope);
7463 Install_Visible_Declarations (Par_Scope);
7465 Uninstall_Declarations (Par_Scope);
7467 -- If parent scope is open and in another unit, and parent has a
7468 -- completion, then the derivation is taking place in the visible
7469 -- part of a child unit. In that case retrieve the full view of
7470 -- the parent momentarily.
7472 elsif not In_Same_Source_Unit (N, Parent_Type) then
7473 Full_P := Full_View (Parent_Type);
7474 Exchange_Declarations (Parent_Type);
7476 Exchange_Declarations (Full_P);
7478 -- Otherwise it is a local derivation
7483 end Build_Full_Derivation;
7485 --------------------
7486 -- Copy_And_Build --
7487 --------------------
7489 procedure Copy_And_Build is
7490 Full_Parent : Entity_Id := Parent_Type;
7493 -- If the parent is itself derived from another private type,
7494 -- installing the private declarations has not affected its
7495 -- privacy status, so use its own full view explicitly.
7497 if Is_Private_Type (Full_Parent)
7498 and then Present (Full_View (Full_Parent))
7500 Full_Parent := Full_View (Full_Parent);
7503 -- And its underlying full view if necessary
7505 if Is_Private_Type (Full_Parent)
7506 and then Present (Underlying_Full_View (Full_Parent))
7508 Full_Parent := Underlying_Full_View (Full_Parent);
7511 -- For record, access and most enumeration types, derivation from
7512 -- the full view requires a fully-fledged declaration. In the other
7513 -- cases, just use an itype.
7515 if Ekind (Full_Parent) in Record_Kind
7516 or else Ekind (Full_Parent) in Access_Kind
7518 (Ekind (Full_Parent) in Enumeration_Kind
7519 and then not Is_Standard_Character_Type (Full_Parent)
7520 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7522 -- Copy and adjust declaration to provide a completion for what
7523 -- is originally a private declaration. Indicate that full view
7524 -- is internally generated.
7526 Set_Comes_From_Source (Full_N, False);
7527 Set_Comes_From_Source (Full_Der, False);
7528 Set_Parent (Full_Der, Full_N);
7529 Set_Defining_Identifier (Full_N, Full_Der);
7531 -- If there are no constraints, adjust the subtype mark
7533 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7534 N_Subtype_Indication
7536 Set_Subtype_Indication
7537 (Type_Definition (Full_N),
7538 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7541 Insert_After (N, Full_N);
7543 -- Build full view of derived type from full view of parent which
7544 -- is now installed. Subprograms have been derived on the partial
7545 -- view, the completion does not derive them anew.
7547 if Ekind (Full_Parent) in Record_Kind then
7549 -- If parent type is tagged, the completion inherits the proper
7550 -- primitive operations.
7552 if Is_Tagged_Type (Parent_Type) then
7553 Build_Derived_Record_Type
7554 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7556 Build_Derived_Record_Type
7557 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7562 (Full_N, Full_Parent, Full_Der,
7563 Is_Completion => False, Derive_Subps => False);
7566 -- The full declaration has been introduced into the tree and
7567 -- processed in the step above. It should not be analyzed again
7568 -- (when encountered later in the current list of declarations)
7569 -- to prevent spurious name conflicts. The full entity remains
7572 Set_Analyzed (Full_N);
7576 Make_Defining_Identifier (Sloc (Derived_Type),
7577 Chars => Chars (Derived_Type));
7578 Set_Is_Itype (Full_Der);
7579 Set_Associated_Node_For_Itype (Full_Der, N);
7580 Set_Parent (Full_Der, N);
7582 (N, Full_Parent, Full_Der,
7583 Is_Completion => False, Derive_Subps => False);
7586 Set_Has_Private_Declaration (Full_Der);
7587 Set_Has_Private_Declaration (Derived_Type);
7589 Set_Scope (Full_Der, Scope (Derived_Type));
7590 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7591 Set_Has_Size_Clause (Full_Der, False);
7592 Set_Has_Alignment_Clause (Full_Der, False);
7593 Set_Has_Delayed_Freeze (Full_Der);
7594 Set_Is_Frozen (Full_Der, False);
7595 Set_Freeze_Node (Full_Der, Empty);
7596 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7597 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7599 -- The convention on the base type may be set in the private part
7600 -- and not propagated to the subtype until later, so we obtain the
7601 -- convention from the base type of the parent.
7603 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7606 -- Start of processing for Build_Derived_Private_Type
7609 if Is_Tagged_Type (Parent_Type) then
7610 Full_P := Full_View (Parent_Type);
7612 -- A type extension of a type with unknown discriminants is an
7613 -- indefinite type that the back-end cannot handle directly.
7614 -- We treat it as a private type, and build a completion that is
7615 -- derived from the full view of the parent, and hopefully has
7616 -- known discriminants.
7618 -- If the full view of the parent type has an underlying record view,
7619 -- use it to generate the underlying record view of this derived type
7620 -- (required for chains of derivations with unknown discriminants).
7622 -- Minor optimization: we avoid the generation of useless underlying
7623 -- record view entities if the private type declaration has unknown
7624 -- discriminants but its corresponding full view has no
7627 if Has_Unknown_Discriminants (Parent_Type)
7628 and then Present (Full_P)
7629 and then (Has_Discriminants (Full_P)
7630 or else Present (Underlying_Record_View (Full_P)))
7631 and then not In_Open_Scopes (Par_Scope)
7632 and then Expander_Active
7635 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7636 New_Ext : constant Node_Id :=
7638 (Record_Extension_Part (Type_Definition (N)));
7642 Build_Derived_Record_Type
7643 (N, Parent_Type, Derived_Type, Derive_Subps);
7645 -- Build anonymous completion, as a derivation from the full
7646 -- view of the parent. This is not a completion in the usual
7647 -- sense, because the current type is not private.
7650 Make_Full_Type_Declaration (Loc,
7651 Defining_Identifier => Full_Der,
7653 Make_Derived_Type_Definition (Loc,
7654 Subtype_Indication =>
7656 (Subtype_Indication (Type_Definition (N))),
7657 Record_Extension_Part => New_Ext));
7659 -- If the parent type has an underlying record view, use it
7660 -- here to build the new underlying record view.
7662 if Present (Underlying_Record_View (Full_P)) then
7664 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7666 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7667 Underlying_Record_View (Full_P));
7670 Install_Private_Declarations (Par_Scope);
7671 Install_Visible_Declarations (Par_Scope);
7672 Insert_Before (N, Decl);
7674 -- Mark entity as an underlying record view before analysis,
7675 -- to avoid generating the list of its primitive operations
7676 -- (which is not really required for this entity) and thus
7677 -- prevent spurious errors associated with missing overriding
7678 -- of abstract primitives (overridden only for Derived_Type).
7680 Set_Ekind (Full_Der, E_Record_Type);
7681 Set_Is_Underlying_Record_View (Full_Der);
7682 Set_Default_SSO (Full_Der);
7683 Set_No_Reordering (Full_Der, No_Component_Reordering);
7687 pragma Assert (Has_Discriminants (Full_Der)
7688 and then not Has_Unknown_Discriminants (Full_Der));
7690 Uninstall_Declarations (Par_Scope);
7692 -- Freeze the underlying record view, to prevent generation of
7693 -- useless dispatching information, which is simply shared with
7694 -- the real derived type.
7696 Set_Is_Frozen (Full_Der);
7698 -- If the derived type has access discriminants, create
7699 -- references to their anonymous types now, to prevent
7700 -- back-end problems when their first use is in generated
7701 -- bodies of primitives.
7707 E := First_Entity (Full_Der);
7709 while Present (E) loop
7710 if Ekind (E) = E_Discriminant
7711 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7713 Build_Itype_Reference (Etype (E), Decl);
7720 -- Set up links between real entity and underlying record view
7722 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7723 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7726 -- If discriminants are known, build derived record
7729 Build_Derived_Record_Type
7730 (N, Parent_Type, Derived_Type, Derive_Subps);
7735 elsif Has_Discriminants (Parent_Type) then
7737 -- Build partial view of derived type from partial view of parent.
7738 -- This must be done before building the full derivation because the
7739 -- second derivation will modify the discriminants of the first and
7740 -- the discriminants are chained with the rest of the components in
7741 -- the full derivation.
7743 Build_Derived_Record_Type
7744 (N, Parent_Type, Derived_Type, Derive_Subps);
7746 -- Build the full derivation if this is not the anonymous derived
7747 -- base type created by Build_Derived_Record_Type in the constrained
7748 -- case (see point 5. of its head comment) since we build it for the
7749 -- derived subtype. And skip it for protected types altogether, as
7750 -- gigi does not use these types directly.
7752 if Present (Full_View (Parent_Type))
7753 and then not Is_Itype (Derived_Type)
7754 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7757 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7759 Last_Discr : Entity_Id;
7762 -- If this is not a completion, construct the implicit full
7763 -- view by deriving from the full view of the parent type.
7764 -- But if this is a completion, the derived private type
7765 -- being built is a full view and the full derivation can
7766 -- only be its underlying full view.
7768 Build_Full_Derivation;
7770 if not Is_Completion then
7771 Set_Full_View (Derived_Type, Full_Der);
7773 Set_Underlying_Full_View (Derived_Type, Full_Der);
7774 Set_Is_Underlying_Full_View (Full_Der);
7777 if not Is_Base_Type (Derived_Type) then
7778 Set_Full_View (Der_Base, Base_Type (Full_Der));
7781 -- Copy the discriminant list from full view to the partial
7782 -- view (base type and its subtype). Gigi requires that the
7783 -- partial and full views have the same discriminants.
7785 -- Note that since the partial view points to discriminants
7786 -- in the full view, their scope will be that of the full
7787 -- view. This might cause some front end problems and need
7790 Discr := First_Discriminant (Base_Type (Full_Der));
7791 Set_First_Entity (Der_Base, Discr);
7794 Last_Discr := Discr;
7795 Next_Discriminant (Discr);
7796 exit when No (Discr);
7799 Set_Last_Entity (Der_Base, Last_Discr);
7800 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7801 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7805 elsif Present (Full_View (Parent_Type))
7806 and then Has_Discriminants (Full_View (Parent_Type))
7808 if Has_Unknown_Discriminants (Parent_Type)
7809 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7810 N_Subtype_Indication
7813 ("cannot constrain type with unknown discriminants",
7814 Subtype_Indication (Type_Definition (N)));
7818 -- If this is not a completion, construct the implicit full view by
7819 -- deriving from the full view of the parent type. But if this is a
7820 -- completion, the derived private type being built is a full view
7821 -- and the full derivation can only be its underlying full view.
7823 Build_Full_Derivation;
7825 if not Is_Completion then
7826 Set_Full_View (Derived_Type, Full_Der);
7828 Set_Underlying_Full_View (Derived_Type, Full_Der);
7829 Set_Is_Underlying_Full_View (Full_Der);
7832 -- In any case, the primitive operations are inherited from the
7833 -- parent type, not from the internal full view.
7835 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7837 if Derive_Subps then
7838 Derive_Subprograms (Parent_Type, Derived_Type);
7841 Set_Stored_Constraint (Derived_Type, No_Elist);
7843 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7846 -- Untagged type, No discriminants on either view
7848 if Nkind (Subtype_Indication (Type_Definition (N))) =
7849 N_Subtype_Indication
7852 ("illegal constraint on type without discriminants", N);
7855 if Present (Discriminant_Specifications (N))
7856 and then Present (Full_View (Parent_Type))
7857 and then not Is_Tagged_Type (Full_View (Parent_Type))
7859 Error_Msg_N ("cannot add discriminants to untagged type", N);
7862 Set_Stored_Constraint (Derived_Type, No_Elist);
7863 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7864 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7865 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7867 Set_Has_Controlled_Component
7868 (Derived_Type, Has_Controlled_Component
7871 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7873 if not Is_Controlled_Active (Parent_Type) then
7874 Set_Finalize_Storage_Only
7875 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7878 -- If this is not a completion, construct the implicit full view by
7879 -- deriving from the full view of the parent type.
7881 -- ??? If the parent is untagged private and its completion is
7882 -- tagged, this mechanism will not work because we cannot derive from
7883 -- the tagged full view unless we have an extension.
7885 if Present (Full_View (Parent_Type))
7886 and then not Is_Tagged_Type (Full_View (Parent_Type))
7887 and then not Is_Completion
7889 Build_Full_Derivation;
7890 Set_Full_View (Derived_Type, Full_Der);
7894 Set_Has_Unknown_Discriminants (Derived_Type,
7895 Has_Unknown_Discriminants (Parent_Type));
7897 if Is_Private_Type (Derived_Type) then
7898 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7901 -- If the parent base type is in scope, add the derived type to its
7902 -- list of private dependents, because its full view may become
7903 -- visible subsequently (in a nested private part, a body, or in a
7904 -- further child unit).
7906 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7907 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7909 -- Check for unusual case where a type completed by a private
7910 -- derivation occurs within a package nested in a child unit, and
7911 -- the parent is declared in an ancestor.
7913 if Is_Child_Unit (Scope (Current_Scope))
7914 and then Is_Completion
7915 and then In_Private_Part (Current_Scope)
7916 and then Scope (Parent_Type) /= Current_Scope
7918 -- Note that if the parent has a completion in the private part,
7919 -- (which is itself a derivation from some other private type)
7920 -- it is that completion that is visible, there is no full view
7921 -- available, and no special processing is needed.
7923 and then Present (Full_View (Parent_Type))
7925 -- In this case, the full view of the parent type will become
7926 -- visible in the body of the enclosing child, and only then will
7927 -- the current type be possibly non-private. Build an underlying
7928 -- full view that will be installed when the enclosing child body
7931 if Present (Underlying_Full_View (Derived_Type)) then
7932 Full_Der := Underlying_Full_View (Derived_Type);
7934 Build_Full_Derivation;
7935 Set_Underlying_Full_View (Derived_Type, Full_Der);
7936 Set_Is_Underlying_Full_View (Full_Der);
7939 -- The full view will be used to swap entities on entry/exit to
7940 -- the body, and must appear in the entity list for the package.
7942 Append_Entity (Full_Der, Scope (Derived_Type));
7945 end Build_Derived_Private_Type;
7947 -------------------------------
7948 -- Build_Derived_Record_Type --
7949 -------------------------------
7953 -- Ideally we would like to use the same model of type derivation for
7954 -- tagged and untagged record types. Unfortunately this is not quite
7955 -- possible because the semantics of representation clauses is different
7956 -- for tagged and untagged records under inheritance. Consider the
7959 -- type R (...) is [tagged] record ... end record;
7960 -- type T (...) is new R (...) [with ...];
7962 -- The representation clauses for T can specify a completely different
7963 -- record layout from R's. Hence the same component can be placed in two
7964 -- very different positions in objects of type T and R. If R and T are
7965 -- tagged types, representation clauses for T can only specify the layout
7966 -- of non inherited components, thus components that are common in R and T
7967 -- have the same position in objects of type R and T.
7969 -- This has two implications. The first is that the entire tree for R's
7970 -- declaration needs to be copied for T in the untagged case, so that T
7971 -- can be viewed as a record type of its own with its own representation
7972 -- clauses. The second implication is the way we handle discriminants.
7973 -- Specifically, in the untagged case we need a way to communicate to Gigi
7974 -- what are the real discriminants in the record, while for the semantics
7975 -- we need to consider those introduced by the user to rename the
7976 -- discriminants in the parent type. This is handled by introducing the
7977 -- notion of stored discriminants. See below for more.
7979 -- Fortunately the way regular components are inherited can be handled in
7980 -- the same way in tagged and untagged types.
7982 -- To complicate things a bit more the private view of a private extension
7983 -- cannot be handled in the same way as the full view (for one thing the
7984 -- semantic rules are somewhat different). We will explain what differs
7987 -- 2. DISCRIMINANTS UNDER INHERITANCE
7989 -- The semantic rules governing the discriminants of derived types are
7992 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7993 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7995 -- If parent type has discriminants, then the discriminants that are
7996 -- declared in the derived type are [3.4 (11)]:
7998 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
8001 -- o Otherwise, each discriminant of the parent type (implicitly declared
8002 -- in the same order with the same specifications). In this case, the
8003 -- discriminants are said to be "inherited", or if unknown in the parent
8004 -- are also unknown in the derived type.
8006 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
8008 -- o The parent subtype must be constrained;
8010 -- o If the parent type is not a tagged type, then each discriminant of
8011 -- the derived type must be used in the constraint defining a parent
8012 -- subtype. [Implementation note: This ensures that the new discriminant
8013 -- can share storage with an existing discriminant.]
8015 -- For the derived type each discriminant of the parent type is either
8016 -- inherited, constrained to equal some new discriminant of the derived
8017 -- type, or constrained to the value of an expression.
8019 -- When inherited or constrained to equal some new discriminant, the
8020 -- parent discriminant and the discriminant of the derived type are said
8023 -- If a discriminant of the parent type is constrained to a specific value
8024 -- in the derived type definition, then the discriminant is said to be
8025 -- "specified" by that derived type definition.
8027 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
8029 -- We have spoken about stored discriminants in point 1 (introduction)
8030 -- above. There are two sorts of stored discriminants: implicit and
8031 -- explicit. As long as the derived type inherits the same discriminants as
8032 -- the root record type, stored discriminants are the same as regular
8033 -- discriminants, and are said to be implicit. However, if any discriminant
8034 -- in the root type was renamed in the derived type, then the derived
8035 -- type will contain explicit stored discriminants. Explicit stored
8036 -- discriminants are discriminants in addition to the semantically visible
8037 -- discriminants defined for the derived type. Stored discriminants are
8038 -- used by Gigi to figure out what are the physical discriminants in
8039 -- objects of the derived type (see precise definition in einfo.ads).
8040 -- As an example, consider the following:
8042 -- type R (D1, D2, D3 : Int) is record ... end record;
8043 -- type T1 is new R;
8044 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
8045 -- type T3 is new T2;
8046 -- type T4 (Y : Int) is new T3 (Y, 99);
8048 -- The following table summarizes the discriminants and stored
8049 -- discriminants in R and T1 through T4:
8051 -- Type Discrim Stored Discrim Comment
8052 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
8053 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
8054 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
8055 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
8056 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
8058 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
8059 -- find the corresponding discriminant in the parent type, while
8060 -- Original_Record_Component (abbreviated ORC below) the actual physical
8061 -- component that is renamed. Finally the field Is_Completely_Hidden
8062 -- (abbreviated ICH below) is set for all explicit stored discriminants
8063 -- (see einfo.ads for more info). For the above example this gives:
8065 -- Discrim CD ORC ICH
8066 -- ^^^^^^^ ^^ ^^^ ^^^
8067 -- D1 in R empty itself no
8068 -- D2 in R empty itself no
8069 -- D3 in R empty itself no
8071 -- D1 in T1 D1 in R itself no
8072 -- D2 in T1 D2 in R itself no
8073 -- D3 in T1 D3 in R itself no
8075 -- X1 in T2 D3 in T1 D3 in T2 no
8076 -- X2 in T2 D1 in T1 D1 in T2 no
8077 -- D1 in T2 empty itself yes
8078 -- D2 in T2 empty itself yes
8079 -- D3 in T2 empty itself yes
8081 -- X1 in T3 X1 in T2 D3 in T3 no
8082 -- X2 in T3 X2 in T2 D1 in T3 no
8083 -- D1 in T3 empty itself yes
8084 -- D2 in T3 empty itself yes
8085 -- D3 in T3 empty itself yes
8087 -- Y in T4 X1 in T3 D3 in T4 no
8088 -- D1 in T4 empty itself yes
8089 -- D2 in T4 empty itself yes
8090 -- D3 in T4 empty itself yes
8092 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
8094 -- Type derivation for tagged types is fairly straightforward. If no
8095 -- discriminants are specified by the derived type, these are inherited
8096 -- from the parent. No explicit stored discriminants are ever necessary.
8097 -- The only manipulation that is done to the tree is that of adding a
8098 -- _parent field with parent type and constrained to the same constraint
8099 -- specified for the parent in the derived type definition. For instance:
8101 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
8102 -- type T1 is new R with null record;
8103 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
8105 -- are changed into:
8107 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
8108 -- _parent : R (D1, D2, D3);
8111 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
8112 -- _parent : T1 (X2, 88, X1);
8115 -- The discriminants actually present in R, T1 and T2 as well as their CD,
8116 -- ORC and ICH fields are:
8118 -- Discrim CD ORC ICH
8119 -- ^^^^^^^ ^^ ^^^ ^^^
8120 -- D1 in R empty itself no
8121 -- D2 in R empty itself no
8122 -- D3 in R empty itself no
8124 -- D1 in T1 D1 in R D1 in R no
8125 -- D2 in T1 D2 in R D2 in R no
8126 -- D3 in T1 D3 in R D3 in R no
8128 -- X1 in T2 D3 in T1 D3 in R no
8129 -- X2 in T2 D1 in T1 D1 in R no
8131 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
8133 -- Regardless of whether we dealing with a tagged or untagged type
8134 -- we will transform all derived type declarations of the form
8136 -- type T is new R (...) [with ...];
8138 -- subtype S is R (...);
8139 -- type T is new S [with ...];
8141 -- type BT is new R [with ...];
8142 -- subtype T is BT (...);
8144 -- That is, the base derived type is constrained only if it has no
8145 -- discriminants. The reason for doing this is that GNAT's semantic model
8146 -- assumes that a base type with discriminants is unconstrained.
8148 -- Note that, strictly speaking, the above transformation is not always
8149 -- correct. Consider for instance the following excerpt from ACVC b34011a:
8151 -- procedure B34011A is
8152 -- type REC (D : integer := 0) is record
8157 -- type T6 is new Rec;
8158 -- function F return T6;
8163 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
8166 -- The definition of Q6.U is illegal. However transforming Q6.U into
8168 -- type BaseU is new T6;
8169 -- subtype U is BaseU (Q6.F.I)
8171 -- turns U into a legal subtype, which is incorrect. To avoid this problem
8172 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
8173 -- the transformation described above.
8175 -- There is another instance where the above transformation is incorrect.
8179 -- type Base (D : Integer) is tagged null record;
8180 -- procedure P (X : Base);
8182 -- type Der is new Base (2) with null record;
8183 -- procedure P (X : Der);
8186 -- Then the above transformation turns this into
8188 -- type Der_Base is new Base with null record;
8189 -- -- procedure P (X : Base) is implicitly inherited here
8190 -- -- as procedure P (X : Der_Base).
8192 -- subtype Der is Der_Base (2);
8193 -- procedure P (X : Der);
8194 -- -- The overriding of P (X : Der_Base) is illegal since we
8195 -- -- have a parameter conformance problem.
8197 -- To get around this problem, after having semantically processed Der_Base
8198 -- and the rewritten subtype declaration for Der, we copy Der_Base field
8199 -- Discriminant_Constraint from Der so that when parameter conformance is
8200 -- checked when P is overridden, no semantic errors are flagged.
8202 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
8204 -- Regardless of whether we are dealing with a tagged or untagged type
8205 -- we will transform all derived type declarations of the form
8207 -- type R (D1, .., Dn : ...) is [tagged] record ...;
8208 -- type T is new R [with ...];
8210 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
8212 -- The reason for such transformation is that it allows us to implement a
8213 -- very clean form of component inheritance as explained below.
8215 -- Note that this transformation is not achieved by direct tree rewriting
8216 -- and manipulation, but rather by redoing the semantic actions that the
8217 -- above transformation will entail. This is done directly in routine
8218 -- Inherit_Components.
8220 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
8222 -- In both tagged and untagged derived types, regular non discriminant
8223 -- components are inherited in the derived type from the parent type. In
8224 -- the absence of discriminants component, inheritance is straightforward
8225 -- as components can simply be copied from the parent.
8227 -- If the parent has discriminants, inheriting components constrained with
8228 -- these discriminants requires caution. Consider the following example:
8230 -- type R (D1, D2 : Positive) is [tagged] record
8231 -- S : String (D1 .. D2);
8234 -- type T1 is new R [with null record];
8235 -- type T2 (X : positive) is new R (1, X) [with null record];
8237 -- As explained in 6. above, T1 is rewritten as
8238 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
8239 -- which makes the treatment for T1 and T2 identical.
8241 -- What we want when inheriting S, is that references to D1 and D2 in R are
8242 -- replaced with references to their correct constraints, i.e. D1 and D2 in
8243 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
8244 -- with either discriminant references in the derived type or expressions.
8245 -- This replacement is achieved as follows: before inheriting R's
8246 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
8247 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
8248 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
8249 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
8250 -- by String (1 .. X).
8252 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
8254 -- We explain here the rules governing private type extensions relevant to
8255 -- type derivation. These rules are explained on the following example:
8257 -- type D [(...)] is new A [(...)] with private; <-- partial view
8258 -- type D [(...)] is new P [(...)] with null record; <-- full view
8260 -- Type A is called the ancestor subtype of the private extension.
8261 -- Type P is the parent type of the full view of the private extension. It
8262 -- must be A or a type derived from A.
8264 -- The rules concerning the discriminants of private type extensions are
8267 -- o If a private extension inherits known discriminants from the ancestor
8268 -- subtype, then the full view must also inherit its discriminants from
8269 -- the ancestor subtype and the parent subtype of the full view must be
8270 -- constrained if and only if the ancestor subtype is constrained.
8272 -- o If a partial view has unknown discriminants, then the full view may
8273 -- define a definite or an indefinite subtype, with or without
8276 -- o If a partial view has neither known nor unknown discriminants, then
8277 -- the full view must define a definite subtype.
8279 -- o If the ancestor subtype of a private extension has constrained
8280 -- discriminants, then the parent subtype of the full view must impose a
8281 -- statically matching constraint on those discriminants.
8283 -- This means that only the following forms of private extensions are
8286 -- type D is new A with private; <-- partial view
8287 -- type D is new P with null record; <-- full view
8289 -- If A has no discriminants than P has no discriminants, otherwise P must
8290 -- inherit A's discriminants.
8292 -- type D is new A (...) with private; <-- partial view
8293 -- type D is new P (:::) with null record; <-- full view
8295 -- P must inherit A's discriminants and (...) and (:::) must statically
8298 -- subtype A is R (...);
8299 -- type D is new A with private; <-- partial view
8300 -- type D is new P with null record; <-- full view
8302 -- P must have inherited R's discriminants and must be derived from A or
8303 -- any of its subtypes.
8305 -- type D (..) is new A with private; <-- partial view
8306 -- type D (..) is new P [(:::)] with null record; <-- full view
8308 -- No specific constraints on P's discriminants or constraint (:::).
8309 -- Note that A can be unconstrained, but the parent subtype P must either
8310 -- be constrained or (:::) must be present.
8312 -- type D (..) is new A [(...)] with private; <-- partial view
8313 -- type D (..) is new P [(:::)] with null record; <-- full view
8315 -- P's constraints on A's discriminants must statically match those
8316 -- imposed by (...).
8318 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
8320 -- The full view of a private extension is handled exactly as described
8321 -- above. The model chose for the private view of a private extension is
8322 -- the same for what concerns discriminants (i.e. they receive the same
8323 -- treatment as in the tagged case). However, the private view of the
8324 -- private extension always inherits the components of the parent base,
8325 -- without replacing any discriminant reference. Strictly speaking this is
8326 -- incorrect. However, Gigi never uses this view to generate code so this
8327 -- is a purely semantic issue. In theory, a set of transformations similar
8328 -- to those given in 5. and 6. above could be applied to private views of
8329 -- private extensions to have the same model of component inheritance as
8330 -- for non private extensions. However, this is not done because it would
8331 -- further complicate private type processing. Semantically speaking, this
8332 -- leaves us in an uncomfortable situation. As an example consider:
8335 -- type R (D : integer) is tagged record
8336 -- S : String (1 .. D);
8338 -- procedure P (X : R);
8339 -- type T is new R (1) with private;
8341 -- type T is new R (1) with null record;
8344 -- This is transformed into:
8347 -- type R (D : integer) is tagged record
8348 -- S : String (1 .. D);
8350 -- procedure P (X : R);
8351 -- type T is new R (1) with private;
8353 -- type BaseT is new R with null record;
8354 -- subtype T is BaseT (1);
8357 -- (strictly speaking the above is incorrect Ada)
8359 -- From the semantic standpoint the private view of private extension T
8360 -- should be flagged as constrained since one can clearly have
8364 -- in a unit withing Pack. However, when deriving subprograms for the
8365 -- private view of private extension T, T must be seen as unconstrained
8366 -- since T has discriminants (this is a constraint of the current
8367 -- subprogram derivation model). Thus, when processing the private view of
8368 -- a private extension such as T, we first mark T as unconstrained, we
8369 -- process it, we perform program derivation and just before returning from
8370 -- Build_Derived_Record_Type we mark T as constrained.
8372 -- ??? Are there are other uncomfortable cases that we will have to
8375 -- 10. RECORD_TYPE_WITH_PRIVATE complications
8377 -- Types that are derived from a visible record type and have a private
8378 -- extension present other peculiarities. They behave mostly like private
8379 -- types, but if they have primitive operations defined, these will not
8380 -- have the proper signatures for further inheritance, because other
8381 -- primitive operations will use the implicit base that we define for
8382 -- private derivations below. This affect subprogram inheritance (see
8383 -- Derive_Subprograms for details). We also derive the implicit base from
8384 -- the base type of the full view, so that the implicit base is a record
8385 -- type and not another private type, This avoids infinite loops.
8387 procedure Build_Derived_Record_Type
8389 Parent_Type : Entity_Id;
8390 Derived_Type : Entity_Id;
8391 Derive_Subps : Boolean := True)
8393 Discriminant_Specs : constant Boolean :=
8394 Present (Discriminant_Specifications (N));
8395 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
8396 Loc : constant Source_Ptr := Sloc (N);
8397 Private_Extension : constant Boolean :=
8398 Nkind (N) = N_Private_Extension_Declaration;
8399 Assoc_List : Elist_Id;
8400 Constraint_Present : Boolean;
8402 Discrim : Entity_Id;
8404 Inherit_Discrims : Boolean := False;
8405 Last_Discrim : Entity_Id;
8406 New_Base : Entity_Id;
8408 New_Discrs : Elist_Id;
8409 New_Indic : Node_Id;
8410 Parent_Base : Entity_Id;
8411 Save_Etype : Entity_Id;
8412 Save_Discr_Constr : Elist_Id;
8413 Save_Next_Entity : Entity_Id;
8416 Discs : Elist_Id := New_Elmt_List;
8417 -- An empty Discs list means that there were no constraints in the
8418 -- subtype indication or that there was an error processing it.
8421 if Ekind (Parent_Type) = E_Record_Type_With_Private
8422 and then Present (Full_View (Parent_Type))
8423 and then Has_Discriminants (Parent_Type)
8425 Parent_Base := Base_Type (Full_View (Parent_Type));
8427 Parent_Base := Base_Type (Parent_Type);
8430 -- AI05-0115 : if this is a derivation from a private type in some
8431 -- other scope that may lead to invisible components for the derived
8432 -- type, mark it accordingly.
8434 if Is_Private_Type (Parent_Type) then
8435 if Scope (Parent_Type) = Scope (Derived_Type) then
8438 elsif In_Open_Scopes (Scope (Parent_Type))
8439 and then In_Private_Part (Scope (Parent_Type))
8444 Set_Has_Private_Ancestor (Derived_Type);
8448 Set_Has_Private_Ancestor
8449 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8452 -- Before we start the previously documented transformations, here is
8453 -- little fix for size and alignment of tagged types. Normally when we
8454 -- derive type D from type P, we copy the size and alignment of P as the
8455 -- default for D, and in the absence of explicit representation clauses
8456 -- for D, the size and alignment are indeed the same as the parent.
8458 -- But this is wrong for tagged types, since fields may be added, and
8459 -- the default size may need to be larger, and the default alignment may
8460 -- need to be larger.
8462 -- We therefore reset the size and alignment fields in the tagged case.
8463 -- Note that the size and alignment will in any case be at least as
8464 -- large as the parent type (since the derived type has a copy of the
8465 -- parent type in the _parent field)
8467 -- The type is also marked as being tagged here, which is needed when
8468 -- processing components with a self-referential anonymous access type
8469 -- in the call to Check_Anonymous_Access_Components below. Note that
8470 -- this flag is also set later on for completeness.
8473 Set_Is_Tagged_Type (Derived_Type);
8474 Init_Size_Align (Derived_Type);
8477 -- STEP 0a: figure out what kind of derived type declaration we have
8479 if Private_Extension then
8481 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8482 Set_Default_SSO (Derived_Type);
8483 Set_No_Reordering (Derived_Type, No_Component_Reordering);
8486 Type_Def := Type_Definition (N);
8488 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8489 -- Parent_Base can be a private type or private extension. However,
8490 -- for tagged types with an extension the newly added fields are
8491 -- visible and hence the Derived_Type is always an E_Record_Type.
8492 -- (except that the parent may have its own private fields).
8493 -- For untagged types we preserve the Ekind of the Parent_Base.
8495 if Present (Record_Extension_Part (Type_Def)) then
8496 Set_Ekind (Derived_Type, E_Record_Type);
8497 Set_Default_SSO (Derived_Type);
8498 Set_No_Reordering (Derived_Type, No_Component_Reordering);
8500 -- Create internal access types for components with anonymous
8503 if Ada_Version >= Ada_2005 then
8504 Check_Anonymous_Access_Components
8505 (N, Derived_Type, Derived_Type,
8506 Component_List (Record_Extension_Part (Type_Def)));
8510 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8514 -- Indic can either be an N_Identifier if the subtype indication
8515 -- contains no constraint or an N_Subtype_Indication if the subtype
8516 -- indication has a constraint.
8518 Indic := Subtype_Indication (Type_Def);
8519 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8521 -- Check that the type has visible discriminants. The type may be
8522 -- a private type with unknown discriminants whose full view has
8523 -- discriminants which are invisible.
8525 if Constraint_Present then
8526 if not Has_Discriminants (Parent_Base)
8528 (Has_Unknown_Discriminants (Parent_Base)
8529 and then Is_Private_Type (Parent_Base))
8532 ("invalid constraint: type has no discriminant",
8533 Constraint (Indic));
8535 Constraint_Present := False;
8536 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8538 elsif Is_Constrained (Parent_Type) then
8540 ("invalid constraint: parent type is already constrained",
8541 Constraint (Indic));
8543 Constraint_Present := False;
8544 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8548 -- STEP 0b: If needed, apply transformation given in point 5. above
8550 if not Private_Extension
8551 and then Has_Discriminants (Parent_Type)
8552 and then not Discriminant_Specs
8553 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8555 -- First, we must analyze the constraint (see comment in point 5.)
8556 -- The constraint may come from the subtype indication of the full
8559 if Constraint_Present then
8560 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8562 -- If there is no explicit constraint, there might be one that is
8563 -- inherited from a constrained parent type. In that case verify that
8564 -- it conforms to the constraint in the partial view. In perverse
8565 -- cases the parent subtypes of the partial and full view can have
8566 -- different constraints.
8568 elsif Present (Stored_Constraint (Parent_Type)) then
8569 New_Discrs := Stored_Constraint (Parent_Type);
8572 New_Discrs := No_Elist;
8575 if Has_Discriminants (Derived_Type)
8576 and then Has_Private_Declaration (Derived_Type)
8577 and then Present (Discriminant_Constraint (Derived_Type))
8578 and then Present (New_Discrs)
8580 -- Verify that constraints of the full view statically match
8581 -- those given in the partial view.
8587 C1 := First_Elmt (New_Discrs);
8588 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8589 while Present (C1) and then Present (C2) loop
8590 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8592 (Is_OK_Static_Expression (Node (C1))
8593 and then Is_OK_Static_Expression (Node (C2))
8595 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8600 if Constraint_Present then
8602 ("constraint not conformant to previous declaration",
8606 ("constraint of full view is incompatible "
8607 & "with partial view", N);
8617 -- Insert and analyze the declaration for the unconstrained base type
8619 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8622 Make_Full_Type_Declaration (Loc,
8623 Defining_Identifier => New_Base,
8625 Make_Derived_Type_Definition (Loc,
8626 Abstract_Present => Abstract_Present (Type_Def),
8627 Limited_Present => Limited_Present (Type_Def),
8628 Subtype_Indication =>
8629 New_Occurrence_Of (Parent_Base, Loc),
8630 Record_Extension_Part =>
8631 Relocate_Node (Record_Extension_Part (Type_Def)),
8632 Interface_List => Interface_List (Type_Def)));
8634 Set_Parent (New_Decl, Parent (N));
8635 Mark_Rewrite_Insertion (New_Decl);
8636 Insert_Before (N, New_Decl);
8638 -- In the extension case, make sure ancestor is frozen appropriately
8639 -- (see also non-discriminated case below).
8641 if Present (Record_Extension_Part (Type_Def))
8642 or else Is_Interface (Parent_Base)
8644 Freeze_Before (New_Decl, Parent_Type);
8647 -- Note that this call passes False for the Derive_Subps parameter
8648 -- because subprogram derivation is deferred until after creating
8649 -- the subtype (see below).
8652 (New_Decl, Parent_Base, New_Base,
8653 Is_Completion => False, Derive_Subps => False);
8655 -- ??? This needs re-examination to determine whether the
8656 -- above call can simply be replaced by a call to Analyze.
8658 Set_Analyzed (New_Decl);
8660 -- Insert and analyze the declaration for the constrained subtype
8662 if Constraint_Present then
8664 Make_Subtype_Indication (Loc,
8665 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8666 Constraint => Relocate_Node (Constraint (Indic)));
8670 Constr_List : constant List_Id := New_List;
8675 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8676 while Present (C) loop
8679 -- It is safe here to call New_Copy_Tree since we called
8680 -- Force_Evaluation on each constraint previously
8681 -- in Build_Discriminant_Constraints.
8683 Append (New_Copy_Tree (Expr), To => Constr_List);
8689 Make_Subtype_Indication (Loc,
8690 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8692 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8697 Make_Subtype_Declaration (Loc,
8698 Defining_Identifier => Derived_Type,
8699 Subtype_Indication => New_Indic));
8703 -- Derivation of subprograms must be delayed until the full subtype
8704 -- has been established, to ensure proper overriding of subprograms
8705 -- inherited by full types. If the derivations occurred as part of
8706 -- the call to Build_Derived_Type above, then the check for type
8707 -- conformance would fail because earlier primitive subprograms
8708 -- could still refer to the full type prior the change to the new
8709 -- subtype and hence would not match the new base type created here.
8710 -- Subprograms are not derived, however, when Derive_Subps is False
8711 -- (since otherwise there could be redundant derivations).
8713 if Derive_Subps then
8714 Derive_Subprograms (Parent_Type, Derived_Type);
8717 -- For tagged types the Discriminant_Constraint of the new base itype
8718 -- is inherited from the first subtype so that no subtype conformance
8719 -- problem arise when the first subtype overrides primitive
8720 -- operations inherited by the implicit base type.
8723 Set_Discriminant_Constraint
8724 (New_Base, Discriminant_Constraint (Derived_Type));
8730 -- If we get here Derived_Type will have no discriminants or it will be
8731 -- a discriminated unconstrained base type.
8733 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8737 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8738 -- The declaration of a specific descendant of an interface type
8739 -- freezes the interface type (RM 13.14).
8741 if not Private_Extension or else Is_Interface (Parent_Base) then
8742 Freeze_Before (N, Parent_Type);
8745 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8746 -- cannot be declared at a deeper level than its parent type is
8747 -- removed. The check on derivation within a generic body is also
8748 -- relaxed, but there's a restriction that a derived tagged type
8749 -- cannot be declared in a generic body if it's derived directly
8750 -- or indirectly from a formal type of that generic.
8752 if Ada_Version >= Ada_2005 then
8753 if Present (Enclosing_Generic_Body (Derived_Type)) then
8755 Ancestor_Type : Entity_Id;
8758 -- Check to see if any ancestor of the derived type is a
8761 Ancestor_Type := Parent_Type;
8762 while not Is_Generic_Type (Ancestor_Type)
8763 and then Etype (Ancestor_Type) /= Ancestor_Type
8765 Ancestor_Type := Etype (Ancestor_Type);
8768 -- If the derived type does have a formal type as an
8769 -- ancestor, then it's an error if the derived type is
8770 -- declared within the body of the generic unit that
8771 -- declares the formal type in its generic formal part. It's
8772 -- sufficient to check whether the ancestor type is declared
8773 -- inside the same generic body as the derived type (such as
8774 -- within a nested generic spec), in which case the
8775 -- derivation is legal. If the formal type is declared
8776 -- outside of that generic body, then it's guaranteed that
8777 -- the derived type is declared within the generic body of
8778 -- the generic unit declaring the formal type.
8780 if Is_Generic_Type (Ancestor_Type)
8781 and then Enclosing_Generic_Body (Ancestor_Type) /=
8782 Enclosing_Generic_Body (Derived_Type)
8785 ("parent type of& must not be descendant of formal type"
8786 & " of an enclosing generic body",
8787 Indic, Derived_Type);
8792 elsif Type_Access_Level (Derived_Type) /=
8793 Type_Access_Level (Parent_Type)
8794 and then not Is_Generic_Type (Derived_Type)
8796 if Is_Controlled (Parent_Type) then
8798 ("controlled type must be declared at the library level",
8802 ("type extension at deeper accessibility level than parent",
8808 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8811 and then GB /= Enclosing_Generic_Body (Parent_Base)
8814 ("parent type of& must not be outside generic body"
8816 Indic, Derived_Type);
8822 -- Ada 2005 (AI-251)
8824 if Ada_Version >= Ada_2005 and then Is_Tagged then
8826 -- "The declaration of a specific descendant of an interface type
8827 -- freezes the interface type" (RM 13.14).
8832 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8833 Iface := First (Interface_List (Type_Def));
8834 while Present (Iface) loop
8835 Freeze_Before (N, Etype (Iface));
8842 -- STEP 1b : preliminary cleanup of the full view of private types
8844 -- If the type is already marked as having discriminants, then it's the
8845 -- completion of a private type or private extension and we need to
8846 -- retain the discriminants from the partial view if the current
8847 -- declaration has Discriminant_Specifications so that we can verify
8848 -- conformance. However, we must remove any existing components that
8849 -- were inherited from the parent (and attached in Copy_And_Swap)
8850 -- because the full type inherits all appropriate components anyway, and
8851 -- we do not want the partial view's components interfering.
8853 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8854 Discrim := First_Discriminant (Derived_Type);
8856 Last_Discrim := Discrim;
8857 Next_Discriminant (Discrim);
8858 exit when No (Discrim);
8861 Set_Last_Entity (Derived_Type, Last_Discrim);
8863 -- In all other cases wipe out the list of inherited components (even
8864 -- inherited discriminants), it will be properly rebuilt here.
8867 Set_First_Entity (Derived_Type, Empty);
8868 Set_Last_Entity (Derived_Type, Empty);
8871 -- STEP 1c: Initialize some flags for the Derived_Type
8873 -- The following flags must be initialized here so that
8874 -- Process_Discriminants can check that discriminants of tagged types do
8875 -- not have a default initial value and that access discriminants are
8876 -- only specified for limited records. For completeness, these flags are
8877 -- also initialized along with all the other flags below.
8879 -- AI-419: Limitedness is not inherited from an interface parent, so to
8880 -- be limited in that case the type must be explicitly declared as
8881 -- limited. However, task and protected interfaces are always limited.
8883 if Limited_Present (Type_Def) then
8884 Set_Is_Limited_Record (Derived_Type);
8886 elsif Is_Limited_Record (Parent_Type)
8887 or else (Present (Full_View (Parent_Type))
8888 and then Is_Limited_Record (Full_View (Parent_Type)))
8890 if not Is_Interface (Parent_Type)
8891 or else Is_Synchronized_Interface (Parent_Type)
8892 or else Is_Protected_Interface (Parent_Type)
8893 or else Is_Task_Interface (Parent_Type)
8895 Set_Is_Limited_Record (Derived_Type);
8899 -- STEP 2a: process discriminants of derived type if any
8901 Push_Scope (Derived_Type);
8903 if Discriminant_Specs then
8904 Set_Has_Unknown_Discriminants (Derived_Type, False);
8906 -- The following call initializes fields Has_Discriminants and
8907 -- Discriminant_Constraint, unless we are processing the completion
8908 -- of a private type declaration.
8910 Check_Or_Process_Discriminants (N, Derived_Type);
8912 -- For untagged types, the constraint on the Parent_Type must be
8913 -- present and is used to rename the discriminants.
8915 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8916 Error_Msg_N ("untagged parent must have discriminants", Indic);
8918 elsif not Is_Tagged and then not Constraint_Present then
8920 ("discriminant constraint needed for derived untagged records",
8923 -- Otherwise the parent subtype must be constrained unless we have a
8924 -- private extension.
8926 elsif not Constraint_Present
8927 and then not Private_Extension
8928 and then not Is_Constrained (Parent_Type)
8931 ("unconstrained type not allowed in this context", Indic);
8933 elsif Constraint_Present then
8934 -- The following call sets the field Corresponding_Discriminant
8935 -- for the discriminants in the Derived_Type.
8937 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8939 -- For untagged types all new discriminants must rename
8940 -- discriminants in the parent. For private extensions new
8941 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8943 Discrim := First_Discriminant (Derived_Type);
8944 while Present (Discrim) loop
8946 and then No (Corresponding_Discriminant (Discrim))
8949 ("new discriminants must constrain old ones", Discrim);
8951 elsif Private_Extension
8952 and then Present (Corresponding_Discriminant (Discrim))
8955 ("only static constraints allowed for parent"
8956 & " discriminants in the partial view", Indic);
8960 -- If a new discriminant is used in the constraint, then its
8961 -- subtype must be statically compatible with the parent
8962 -- discriminant's subtype (3.7(15)).
8964 -- However, if the record contains an array constrained by
8965 -- the discriminant but with some different bound, the compiler
8966 -- tries to create a smaller range for the discriminant type.
8967 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8968 -- the discriminant type is a scalar type, the check must use
8969 -- the original discriminant type in the parent declaration.
8972 Corr_Disc : constant Entity_Id :=
8973 Corresponding_Discriminant (Discrim);
8974 Disc_Type : constant Entity_Id := Etype (Discrim);
8975 Corr_Type : Entity_Id;
8978 if Present (Corr_Disc) then
8979 if Is_Scalar_Type (Disc_Type) then
8981 Entity (Discriminant_Type (Parent (Corr_Disc)));
8983 Corr_Type := Etype (Corr_Disc);
8987 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8990 ("subtype must be compatible "
8991 & "with parent discriminant",
8997 Next_Discriminant (Discrim);
9000 -- Check whether the constraints of the full view statically
9001 -- match those imposed by the parent subtype [7.3(13)].
9003 if Present (Stored_Constraint (Derived_Type)) then
9008 C1 := First_Elmt (Discs);
9009 C2 := First_Elmt (Stored_Constraint (Derived_Type));
9010 while Present (C1) and then Present (C2) loop
9012 Fully_Conformant_Expressions (Node (C1), Node (C2))
9015 ("not conformant with previous declaration",
9026 -- STEP 2b: No new discriminants, inherit discriminants if any
9029 if Private_Extension then
9030 Set_Has_Unknown_Discriminants
9032 Has_Unknown_Discriminants (Parent_Type)
9033 or else Unknown_Discriminants_Present (N));
9035 -- The partial view of the parent may have unknown discriminants,
9036 -- but if the full view has discriminants and the parent type is
9037 -- in scope they must be inherited.
9039 elsif Has_Unknown_Discriminants (Parent_Type)
9041 (not Has_Discriminants (Parent_Type)
9042 or else not In_Open_Scopes (Scope (Parent_Type)))
9044 Set_Has_Unknown_Discriminants (Derived_Type);
9047 if not Has_Unknown_Discriminants (Derived_Type)
9048 and then not Has_Unknown_Discriminants (Parent_Base)
9049 and then Has_Discriminants (Parent_Type)
9051 Inherit_Discrims := True;
9052 Set_Has_Discriminants
9053 (Derived_Type, True);
9054 Set_Discriminant_Constraint
9055 (Derived_Type, Discriminant_Constraint (Parent_Base));
9058 -- The following test is true for private types (remember
9059 -- transformation 5. is not applied to those) and in an error
9062 if Constraint_Present then
9063 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
9066 -- For now mark a new derived type as constrained only if it has no
9067 -- discriminants. At the end of Build_Derived_Record_Type we properly
9068 -- set this flag in the case of private extensions. See comments in
9069 -- point 9. just before body of Build_Derived_Record_Type.
9073 not (Inherit_Discrims
9074 or else Has_Unknown_Discriminants (Derived_Type)));
9077 -- STEP 3: initialize fields of derived type
9079 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
9080 Set_Stored_Constraint (Derived_Type, No_Elist);
9082 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
9083 -- but cannot be interfaces
9085 if not Private_Extension
9086 and then Ekind (Derived_Type) /= E_Private_Type
9087 and then Ekind (Derived_Type) /= E_Limited_Private_Type
9089 if Interface_Present (Type_Def) then
9090 Analyze_Interface_Declaration (Derived_Type, Type_Def);
9093 Set_Interfaces (Derived_Type, No_Elist);
9096 -- Fields inherited from the Parent_Type
9098 Set_Has_Specified_Layout
9099 (Derived_Type, Has_Specified_Layout (Parent_Type));
9100 Set_Is_Limited_Composite
9101 (Derived_Type, Is_Limited_Composite (Parent_Type));
9102 Set_Is_Private_Composite
9103 (Derived_Type, Is_Private_Composite (Parent_Type));
9105 if Is_Tagged_Type (Parent_Type) then
9106 Set_No_Tagged_Streams_Pragma
9107 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9110 -- Fields inherited from the Parent_Base
9112 Set_Has_Controlled_Component
9113 (Derived_Type, Has_Controlled_Component (Parent_Base));
9114 Set_Has_Non_Standard_Rep
9115 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
9116 Set_Has_Primitive_Operations
9117 (Derived_Type, Has_Primitive_Operations (Parent_Base));
9119 -- Set fields for private derived types
9121 if Is_Private_Type (Derived_Type) then
9122 Set_Depends_On_Private (Derived_Type, True);
9123 Set_Private_Dependents (Derived_Type, New_Elmt_List);
9126 -- Inherit fields for non-private types. If this is the completion of a
9127 -- derivation from a private type, the parent itself is private and the
9128 -- attributes come from its full view, which must be present.
9130 if Is_Record_Type (Derived_Type) then
9132 Parent_Full : Entity_Id;
9135 if Is_Private_Type (Parent_Base)
9136 and then not Is_Record_Type (Parent_Base)
9138 Parent_Full := Full_View (Parent_Base);
9140 Parent_Full := Parent_Base;
9143 Set_Component_Alignment
9144 (Derived_Type, Component_Alignment (Parent_Full));
9146 (Derived_Type, C_Pass_By_Copy (Parent_Full));
9147 Set_Has_Complex_Representation
9148 (Derived_Type, Has_Complex_Representation (Parent_Full));
9150 -- For untagged types, inherit the layout by default to avoid
9151 -- costly changes of representation for type conversions.
9153 if not Is_Tagged then
9154 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Full));
9155 Set_No_Reordering (Derived_Type, No_Reordering (Parent_Full));
9160 -- Set fields for tagged types
9163 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
9165 -- All tagged types defined in Ada.Finalization are controlled
9167 if Chars (Scope (Derived_Type)) = Name_Finalization
9168 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
9169 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
9171 Set_Is_Controlled (Derived_Type);
9173 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
9176 -- Minor optimization: there is no need to generate the class-wide
9177 -- entity associated with an underlying record view.
9179 if not Is_Underlying_Record_View (Derived_Type) then
9180 Make_Class_Wide_Type (Derived_Type);
9183 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
9185 if Has_Discriminants (Derived_Type)
9186 and then Constraint_Present
9188 Set_Stored_Constraint
9189 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
9192 if Ada_Version >= Ada_2005 then
9194 Ifaces_List : Elist_Id;
9197 -- Checks rules 3.9.4 (13/2 and 14/2)
9199 if Comes_From_Source (Derived_Type)
9200 and then not Is_Private_Type (Derived_Type)
9201 and then Is_Interface (Parent_Type)
9202 and then not Is_Interface (Derived_Type)
9204 if Is_Task_Interface (Parent_Type) then
9206 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
9209 elsif Is_Protected_Interface (Parent_Type) then
9211 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
9216 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
9218 Check_Interfaces (N, Type_Def);
9220 -- Ada 2005 (AI-251): Collect the list of progenitors that are
9221 -- not already in the parents.
9225 Ifaces_List => Ifaces_List,
9226 Exclude_Parents => True);
9228 Set_Interfaces (Derived_Type, Ifaces_List);
9230 -- If the derived type is the anonymous type created for
9231 -- a declaration whose parent has a constraint, propagate
9232 -- the interface list to the source type. This must be done
9233 -- prior to the completion of the analysis of the source type
9234 -- because the components in the extension may contain current
9235 -- instances whose legality depends on some ancestor.
9237 if Is_Itype (Derived_Type) then
9239 Def : constant Node_Id :=
9240 Associated_Node_For_Itype (Derived_Type);
9243 and then Nkind (Def) = N_Full_Type_Declaration
9246 (Defining_Identifier (Def), Ifaces_List);
9251 -- A type extension is automatically Ghost when one of its
9252 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
9253 -- also inherited when the parent type is Ghost, but this is
9254 -- done in Build_Derived_Type as the mechanism also handles
9255 -- untagged derivations.
9257 if Implements_Ghost_Interface (Derived_Type) then
9258 Set_Is_Ghost_Entity (Derived_Type);
9264 -- STEP 4: Inherit components from the parent base and constrain them.
9265 -- Apply the second transformation described in point 6. above.
9267 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
9268 or else not Has_Discriminants (Parent_Type)
9269 or else not Is_Constrained (Parent_Type)
9273 Constrs := Discriminant_Constraint (Parent_Type);
9278 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
9280 -- STEP 5a: Copy the parent record declaration for untagged types
9282 Set_Has_Implicit_Dereference
9283 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
9285 if not Is_Tagged then
9287 -- Discriminant_Constraint (Derived_Type) has been properly
9288 -- constructed. Save it and temporarily set it to Empty because we
9289 -- do not want the call to New_Copy_Tree below to mess this list.
9291 if Has_Discriminants (Derived_Type) then
9292 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
9293 Set_Discriminant_Constraint (Derived_Type, No_Elist);
9295 Save_Discr_Constr := No_Elist;
9298 -- Save the Etype field of Derived_Type. It is correctly set now,
9299 -- but the call to New_Copy tree may remap it to point to itself,
9300 -- which is not what we want. Ditto for the Next_Entity field.
9302 Save_Etype := Etype (Derived_Type);
9303 Save_Next_Entity := Next_Entity (Derived_Type);
9305 -- Assoc_List maps all stored discriminants in the Parent_Base to
9306 -- stored discriminants in the Derived_Type. It is fundamental that
9307 -- no types or itypes with discriminants other than the stored
9308 -- discriminants appear in the entities declared inside
9309 -- Derived_Type, since the back end cannot deal with it.
9313 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
9315 -- Restore the fields saved prior to the New_Copy_Tree call
9316 -- and compute the stored constraint.
9318 Set_Etype (Derived_Type, Save_Etype);
9319 Set_Next_Entity (Derived_Type, Save_Next_Entity);
9321 if Has_Discriminants (Derived_Type) then
9322 Set_Discriminant_Constraint
9323 (Derived_Type, Save_Discr_Constr);
9324 Set_Stored_Constraint
9325 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
9326 Replace_Components (Derived_Type, New_Decl);
9329 -- Insert the new derived type declaration
9331 Rewrite (N, New_Decl);
9333 -- STEP 5b: Complete the processing for record extensions in generics
9335 -- There is no completion for record extensions declared in the
9336 -- parameter part of a generic, so we need to complete processing for
9337 -- these generic record extensions here. The Record_Type_Definition call
9338 -- will change the Ekind of the components from E_Void to E_Component.
9340 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
9341 Record_Type_Definition (Empty, Derived_Type);
9343 -- STEP 5c: Process the record extension for non private tagged types
9345 elsif not Private_Extension then
9346 Expand_Record_Extension (Derived_Type, Type_Def);
9348 -- Note : previously in ASIS mode we set the Parent_Subtype of the
9349 -- derived type to propagate some semantic information. This led
9350 -- to other ASIS failures and has been removed.
9352 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
9353 -- implemented interfaces if we are in expansion mode
9356 and then Has_Interfaces (Derived_Type)
9358 Add_Interface_Tag_Components (N, Derived_Type);
9361 -- Analyze the record extension
9363 Record_Type_Definition
9364 (Record_Extension_Part (Type_Def), Derived_Type);
9369 -- Nothing else to do if there is an error in the derivation.
9370 -- An unusual case: the full view may be derived from a type in an
9371 -- instance, when the partial view was used illegally as an actual
9372 -- in that instance, leading to a circular definition.
9374 if Etype (Derived_Type) = Any_Type
9375 or else Etype (Parent_Type) = Derived_Type
9380 -- Set delayed freeze and then derive subprograms, we need to do
9381 -- this in this order so that derived subprograms inherit the
9382 -- derived freeze if necessary.
9384 Set_Has_Delayed_Freeze (Derived_Type);
9386 if Derive_Subps then
9387 Derive_Subprograms (Parent_Type, Derived_Type);
9390 -- If we have a private extension which defines a constrained derived
9391 -- type mark as constrained here after we have derived subprograms. See
9392 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9394 if Private_Extension and then Inherit_Discrims then
9395 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9396 Set_Is_Constrained (Derived_Type, True);
9397 Set_Discriminant_Constraint (Derived_Type, Discs);
9399 elsif Is_Constrained (Parent_Type) then
9401 (Derived_Type, True);
9402 Set_Discriminant_Constraint
9403 (Derived_Type, Discriminant_Constraint (Parent_Type));
9407 -- Update the class-wide type, which shares the now-completed entity
9408 -- list with its specific type. In case of underlying record views,
9409 -- we do not generate the corresponding class wide entity.
9412 and then not Is_Underlying_Record_View (Derived_Type)
9415 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9417 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9420 Check_Function_Writable_Actuals (N);
9421 end Build_Derived_Record_Type;
9423 ------------------------
9424 -- Build_Derived_Type --
9425 ------------------------
9427 procedure Build_Derived_Type
9429 Parent_Type : Entity_Id;
9430 Derived_Type : Entity_Id;
9431 Is_Completion : Boolean;
9432 Derive_Subps : Boolean := True)
9434 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9437 -- Set common attributes
9439 Set_Scope (Derived_Type, Current_Scope);
9441 Set_Etype (Derived_Type, Parent_Base);
9442 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9443 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9445 Set_Size_Info (Derived_Type, Parent_Type);
9446 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9447 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9448 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9450 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9451 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9453 if Is_Tagged_Type (Derived_Type) then
9454 Set_No_Tagged_Streams_Pragma
9455 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9458 -- If the parent has primitive routines, set the derived type link
9460 if Has_Primitive_Operations (Parent_Type) then
9461 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9464 -- If the parent type is a private subtype, the convention on the base
9465 -- type may be set in the private part, and not propagated to the
9466 -- subtype until later, so we obtain the convention from the base type.
9468 Set_Convention (Derived_Type, Convention (Parent_Base));
9470 -- Set SSO default for record or array type
9472 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9473 and then Is_Base_Type (Derived_Type)
9475 Set_Default_SSO (Derived_Type);
9478 -- A derived type inherits the Default_Initial_Condition pragma coming
9479 -- from any parent type within the derivation chain.
9481 if Has_DIC (Parent_Type) then
9482 Set_Has_Inherited_DIC (Derived_Type);
9485 -- A derived type inherits any class-wide invariants coming from a
9486 -- parent type or an interface. Note that the invariant procedure of
9487 -- the parent type should not be inherited because the derived type may
9488 -- define invariants of its own.
9490 if not Is_Interface (Derived_Type) then
9491 if Has_Inherited_Invariants (Parent_Type)
9492 or else Has_Inheritable_Invariants (Parent_Type)
9494 Set_Has_Inherited_Invariants (Derived_Type);
9496 elsif Is_Concurrent_Type (Derived_Type)
9497 or else Is_Tagged_Type (Derived_Type)
9502 Iface_Elmt : Elmt_Id;
9507 Ifaces_List => Ifaces,
9508 Exclude_Parents => True);
9510 if Present (Ifaces) then
9511 Iface_Elmt := First_Elmt (Ifaces);
9512 while Present (Iface_Elmt) loop
9513 Iface := Node (Iface_Elmt);
9515 if Has_Inheritable_Invariants (Iface) then
9516 Set_Has_Inherited_Invariants (Derived_Type);
9520 Next_Elmt (Iface_Elmt);
9527 -- We similarly inherit predicates. Note that for scalar derived types
9528 -- the predicate is inherited from the first subtype, and not from its
9529 -- (anonymous) base type.
9531 if Has_Predicates (Parent_Type)
9532 or else Has_Predicates (First_Subtype (Parent_Type))
9534 Set_Has_Predicates (Derived_Type);
9537 -- The derived type inherits the representation clauses of the parent
9539 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9541 -- If the parent type has delayed rep aspects, then mark the derived
9542 -- type as possibly inheriting a delayed rep aspect.
9544 if Has_Delayed_Rep_Aspects (Parent_Type) then
9545 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9548 -- A derived type becomes Ghost when its parent type is also Ghost
9549 -- (SPARK RM 6.9(9)). Note that the Ghost-related attributes are not
9550 -- directly inherited because the Ghost policy in effect may differ.
9552 if Is_Ghost_Entity (Parent_Type) then
9553 Set_Is_Ghost_Entity (Derived_Type);
9556 -- Type dependent processing
9558 case Ekind (Parent_Type) is
9559 when Numeric_Kind =>
9560 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9563 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9565 when Class_Wide_Kind
9569 Build_Derived_Record_Type
9570 (N, Parent_Type, Derived_Type, Derive_Subps);
9573 when Enumeration_Kind =>
9574 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9577 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9579 when Incomplete_Or_Private_Kind =>
9580 Build_Derived_Private_Type
9581 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9583 -- For discriminated types, the derivation includes deriving
9584 -- primitive operations. For others it is done below.
9586 if Is_Tagged_Type (Parent_Type)
9587 or else Has_Discriminants (Parent_Type)
9588 or else (Present (Full_View (Parent_Type))
9589 and then Has_Discriminants (Full_View (Parent_Type)))
9594 when Concurrent_Kind =>
9595 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9598 raise Program_Error;
9601 -- Nothing more to do if some error occurred
9603 if Etype (Derived_Type) = Any_Type then
9607 -- Set delayed freeze and then derive subprograms, we need to do this
9608 -- in this order so that derived subprograms inherit the derived freeze
9611 Set_Has_Delayed_Freeze (Derived_Type);
9613 if Derive_Subps then
9614 Derive_Subprograms (Parent_Type, Derived_Type);
9617 Set_Has_Primitive_Operations
9618 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9619 end Build_Derived_Type;
9621 -----------------------
9622 -- Build_Discriminal --
9623 -----------------------
9625 procedure Build_Discriminal (Discrim : Entity_Id) is
9626 D_Minal : Entity_Id;
9627 CR_Disc : Entity_Id;
9630 -- A discriminal has the same name as the discriminant
9632 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9634 Set_Ekind (D_Minal, E_In_Parameter);
9635 Set_Mechanism (D_Minal, Default_Mechanism);
9636 Set_Etype (D_Minal, Etype (Discrim));
9637 Set_Scope (D_Minal, Current_Scope);
9638 Set_Parent (D_Minal, Parent (Discrim));
9640 Set_Discriminal (Discrim, D_Minal);
9641 Set_Discriminal_Link (D_Minal, Discrim);
9643 -- For task types, build at once the discriminants of the corresponding
9644 -- record, which are needed if discriminants are used in entry defaults
9645 -- and in family bounds.
9647 if Is_Concurrent_Type (Current_Scope)
9649 Is_Limited_Type (Current_Scope)
9651 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9653 Set_Ekind (CR_Disc, E_In_Parameter);
9654 Set_Mechanism (CR_Disc, Default_Mechanism);
9655 Set_Etype (CR_Disc, Etype (Discrim));
9656 Set_Scope (CR_Disc, Current_Scope);
9657 Set_Discriminal_Link (CR_Disc, Discrim);
9658 Set_CR_Discriminant (Discrim, CR_Disc);
9660 end Build_Discriminal;
9662 ------------------------------------
9663 -- Build_Discriminant_Constraints --
9664 ------------------------------------
9666 function Build_Discriminant_Constraints
9669 Derived_Def : Boolean := False) return Elist_Id
9671 C : constant Node_Id := Constraint (Def);
9672 Nb_Discr : constant Nat := Number_Discriminants (T);
9674 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9675 -- Saves the expression corresponding to a given discriminant in T
9677 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9678 -- Return the Position number within array Discr_Expr of a discriminant
9679 -- D within the discriminant list of the discriminated type T.
9681 procedure Process_Discriminant_Expression
9684 -- If this is a discriminant constraint on a partial view, do not
9685 -- generate an overflow check on the discriminant expression. The check
9686 -- will be generated when constraining the full view. Otherwise the
9687 -- backend creates duplicate symbols for the temporaries corresponding
9688 -- to the expressions to be checked, causing spurious assembler errors.
9694 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9698 Disc := First_Discriminant (T);
9699 for J in Discr_Expr'Range loop
9704 Next_Discriminant (Disc);
9707 -- Note: Since this function is called on discriminants that are
9708 -- known to belong to the discriminated type, falling through the
9709 -- loop with no match signals an internal compiler error.
9711 raise Program_Error;
9714 -------------------------------------
9715 -- Process_Discriminant_Expression --
9716 -------------------------------------
9718 procedure Process_Discriminant_Expression
9722 BDT : constant Entity_Id := Base_Type (Etype (D));
9725 -- If this is a discriminant constraint on a partial view, do
9726 -- not generate an overflow on the discriminant expression. The
9727 -- check will be generated when constraining the full view.
9729 if Is_Private_Type (T)
9730 and then Present (Full_View (T))
9732 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9734 Analyze_And_Resolve (Expr, BDT);
9736 end Process_Discriminant_Expression;
9738 -- Declarations local to Build_Discriminant_Constraints
9742 Elist : constant Elist_Id := New_Elmt_List;
9750 Discrim_Present : Boolean := False;
9752 -- Start of processing for Build_Discriminant_Constraints
9755 -- The following loop will process positional associations only.
9756 -- For a positional association, the (single) discriminant is
9757 -- implicitly specified by position, in textual order (RM 3.7.2).
9759 Discr := First_Discriminant (T);
9760 Constr := First (Constraints (C));
9761 for D in Discr_Expr'Range loop
9762 exit when Nkind (Constr) = N_Discriminant_Association;
9765 Error_Msg_N ("too few discriminants given in constraint", C);
9766 return New_Elmt_List;
9768 elsif Nkind (Constr) = N_Range
9769 or else (Nkind (Constr) = N_Attribute_Reference
9770 and then Attribute_Name (Constr) = Name_Range)
9773 ("a range is not a valid discriminant constraint", Constr);
9774 Discr_Expr (D) := Error;
9777 Process_Discriminant_Expression (Constr, Discr);
9778 Discr_Expr (D) := Constr;
9781 Next_Discriminant (Discr);
9785 if No (Discr) and then Present (Constr) then
9786 Error_Msg_N ("too many discriminants given in constraint", Constr);
9787 return New_Elmt_List;
9790 -- Named associations can be given in any order, but if both positional
9791 -- and named associations are used in the same discriminant constraint,
9792 -- then positional associations must occur first, at their normal
9793 -- position. Hence once a named association is used, the rest of the
9794 -- discriminant constraint must use only named associations.
9796 while Present (Constr) loop
9798 -- Positional association forbidden after a named association
9800 if Nkind (Constr) /= N_Discriminant_Association then
9801 Error_Msg_N ("positional association follows named one", Constr);
9802 return New_Elmt_List;
9804 -- Otherwise it is a named association
9807 -- E records the type of the discriminants in the named
9808 -- association. All the discriminants specified in the same name
9809 -- association must have the same type.
9813 -- Search the list of discriminants in T to see if the simple name
9814 -- given in the constraint matches any of them.
9816 Id := First (Selector_Names (Constr));
9817 while Present (Id) loop
9820 -- If Original_Discriminant is present, we are processing a
9821 -- generic instantiation and this is an instance node. We need
9822 -- to find the name of the corresponding discriminant in the
9823 -- actual record type T and not the name of the discriminant in
9824 -- the generic formal. Example:
9827 -- type G (D : int) is private;
9829 -- subtype W is G (D => 1);
9831 -- type Rec (X : int) is record ... end record;
9832 -- package Q is new P (G => Rec);
9834 -- At the point of the instantiation, formal type G is Rec
9835 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9836 -- which really looks like "subtype W is Rec (D => 1);" at
9837 -- the point of instantiation, we want to find the discriminant
9838 -- that corresponds to D in Rec, i.e. X.
9840 if Present (Original_Discriminant (Id))
9841 and then In_Instance
9843 Discr := Find_Corresponding_Discriminant (Id, T);
9847 Discr := First_Discriminant (T);
9848 while Present (Discr) loop
9849 if Chars (Discr) = Chars (Id) then
9854 Next_Discriminant (Discr);
9858 Error_Msg_N ("& does not match any discriminant", Id);
9859 return New_Elmt_List;
9861 -- If the parent type is a generic formal, preserve the
9862 -- name of the discriminant for subsequent instances.
9863 -- see comment at the beginning of this if statement.
9865 elsif Is_Generic_Type (Root_Type (T)) then
9866 Set_Original_Discriminant (Id, Discr);
9870 Position := Pos_Of_Discr (T, Discr);
9872 if Present (Discr_Expr (Position)) then
9873 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9876 -- Each discriminant specified in the same named association
9877 -- must be associated with a separate copy of the
9878 -- corresponding expression.
9880 if Present (Next (Id)) then
9881 Expr := New_Copy_Tree (Expression (Constr));
9882 Set_Parent (Expr, Parent (Expression (Constr)));
9884 Expr := Expression (Constr);
9887 Discr_Expr (Position) := Expr;
9888 Process_Discriminant_Expression (Expr, Discr);
9891 -- A discriminant association with more than one discriminant
9892 -- name is only allowed if the named discriminants are all of
9893 -- the same type (RM 3.7.1(8)).
9896 E := Base_Type (Etype (Discr));
9898 elsif Base_Type (Etype (Discr)) /= E then
9900 ("all discriminants in an association " &
9901 "must have the same type", Id);
9911 -- A discriminant constraint must provide exactly one value for each
9912 -- discriminant of the type (RM 3.7.1(8)).
9914 for J in Discr_Expr'Range loop
9915 if No (Discr_Expr (J)) then
9916 Error_Msg_N ("too few discriminants given in constraint", C);
9917 return New_Elmt_List;
9921 -- Determine if there are discriminant expressions in the constraint
9923 for J in Discr_Expr'Range loop
9924 if Denotes_Discriminant
9925 (Discr_Expr (J), Check_Concurrent => True)
9927 Discrim_Present := True;
9931 -- Build an element list consisting of the expressions given in the
9932 -- discriminant constraint and apply the appropriate checks. The list
9933 -- is constructed after resolving any named discriminant associations
9934 -- and therefore the expressions appear in the textual order of the
9937 Discr := First_Discriminant (T);
9938 for J in Discr_Expr'Range loop
9939 if Discr_Expr (J) /= Error then
9940 Append_Elmt (Discr_Expr (J), Elist);
9942 -- If any of the discriminant constraints is given by a
9943 -- discriminant and we are in a derived type declaration we
9944 -- have a discriminant renaming. Establish link between new
9945 -- and old discriminant. The new discriminant has an implicit
9946 -- dereference if the old one does.
9948 if Denotes_Discriminant (Discr_Expr (J)) then
9951 New_Discr : constant Entity_Id := Entity (Discr_Expr (J));
9954 Set_Corresponding_Discriminant (New_Discr, Discr);
9955 Set_Has_Implicit_Dereference (New_Discr,
9956 Has_Implicit_Dereference (Discr));
9960 -- Force the evaluation of non-discriminant expressions.
9961 -- If we have found a discriminant in the constraint 3.4(26)
9962 -- and 3.8(18) demand that no range checks are performed are
9963 -- after evaluation. If the constraint is for a component
9964 -- definition that has a per-object constraint, expressions are
9965 -- evaluated but not checked either. In all other cases perform
9969 if Discrim_Present then
9972 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9973 and then Has_Per_Object_Constraint
9974 (Defining_Identifier (Parent (Parent (Def))))
9978 elsif Is_Access_Type (Etype (Discr)) then
9979 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9982 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9985 Force_Evaluation (Discr_Expr (J));
9988 -- Check that the designated type of an access discriminant's
9989 -- expression is not a class-wide type unless the discriminant's
9990 -- designated type is also class-wide.
9992 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9993 and then not Is_Class_Wide_Type
9994 (Designated_Type (Etype (Discr)))
9995 and then Etype (Discr_Expr (J)) /= Any_Type
9996 and then Is_Class_Wide_Type
9997 (Designated_Type (Etype (Discr_Expr (J))))
9999 Wrong_Type (Discr_Expr (J), Etype (Discr));
10001 elsif Is_Access_Type (Etype (Discr))
10002 and then not Is_Access_Constant (Etype (Discr))
10003 and then Is_Access_Type (Etype (Discr_Expr (J)))
10004 and then Is_Access_Constant (Etype (Discr_Expr (J)))
10007 ("constraint for discriminant& must be access to variable",
10012 Next_Discriminant (Discr);
10016 end Build_Discriminant_Constraints;
10018 ---------------------------------
10019 -- Build_Discriminated_Subtype --
10020 ---------------------------------
10022 procedure Build_Discriminated_Subtype
10024 Def_Id : Entity_Id;
10026 Related_Nod : Node_Id;
10027 For_Access : Boolean := False)
10029 Has_Discrs : constant Boolean := Has_Discriminants (T);
10030 Constrained : constant Boolean :=
10032 and then not Is_Empty_Elmt_List (Elist)
10033 and then not Is_Class_Wide_Type (T))
10034 or else Is_Constrained (T);
10037 if Ekind (T) = E_Record_Type then
10039 Set_Ekind (Def_Id, E_Private_Subtype);
10040 Set_Is_For_Access_Subtype (Def_Id, True);
10042 Set_Ekind (Def_Id, E_Record_Subtype);
10045 -- Inherit preelaboration flag from base, for types for which it
10046 -- may have been set: records, private types, protected types.
10048 Set_Known_To_Have_Preelab_Init
10049 (Def_Id, Known_To_Have_Preelab_Init (T));
10051 elsif Ekind (T) = E_Task_Type then
10052 Set_Ekind (Def_Id, E_Task_Subtype);
10054 elsif Ekind (T) = E_Protected_Type then
10055 Set_Ekind (Def_Id, E_Protected_Subtype);
10056 Set_Known_To_Have_Preelab_Init
10057 (Def_Id, Known_To_Have_Preelab_Init (T));
10059 elsif Is_Private_Type (T) then
10060 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10061 Set_Known_To_Have_Preelab_Init
10062 (Def_Id, Known_To_Have_Preelab_Init (T));
10064 -- Private subtypes may have private dependents
10066 Set_Private_Dependents (Def_Id, New_Elmt_List);
10068 elsif Is_Class_Wide_Type (T) then
10069 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
10072 -- Incomplete type. Attach subtype to list of dependents, to be
10073 -- completed with full view of parent type, unless is it the
10074 -- designated subtype of a record component within an init_proc.
10075 -- This last case arises for a component of an access type whose
10076 -- designated type is incomplete (e.g. a Taft Amendment type).
10077 -- The designated subtype is within an inner scope, and needs no
10078 -- elaboration, because only the access type is needed in the
10079 -- initialization procedure.
10081 if Ekind (T) = E_Incomplete_Type then
10082 Set_Ekind (Def_Id, E_Incomplete_Subtype);
10084 Set_Ekind (Def_Id, Ekind (T));
10087 if For_Access and then Within_Init_Proc then
10090 Append_Elmt (Def_Id, Private_Dependents (T));
10094 Set_Etype (Def_Id, T);
10095 Init_Size_Align (Def_Id);
10096 Set_Has_Discriminants (Def_Id, Has_Discrs);
10097 Set_Is_Constrained (Def_Id, Constrained);
10099 Set_First_Entity (Def_Id, First_Entity (T));
10100 Set_Last_Entity (Def_Id, Last_Entity (T));
10101 Set_Has_Implicit_Dereference
10102 (Def_Id, Has_Implicit_Dereference (T));
10103 Set_Has_Pragma_Unreferenced_Objects
10104 (Def_Id, Has_Pragma_Unreferenced_Objects (T));
10106 -- If the subtype is the completion of a private declaration, there may
10107 -- have been representation clauses for the partial view, and they must
10108 -- be preserved. Build_Derived_Type chains the inherited clauses with
10109 -- the ones appearing on the extension. If this comes from a subtype
10110 -- declaration, all clauses are inherited.
10112 if No (First_Rep_Item (Def_Id)) then
10113 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10116 if Is_Tagged_Type (T) then
10117 Set_Is_Tagged_Type (Def_Id);
10118 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
10119 Make_Class_Wide_Type (Def_Id);
10122 Set_Stored_Constraint (Def_Id, No_Elist);
10125 Set_Discriminant_Constraint (Def_Id, Elist);
10126 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
10129 if Is_Tagged_Type (T) then
10131 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
10132 -- concurrent record type (which has the list of primitive
10135 if Ada_Version >= Ada_2005
10136 and then Is_Concurrent_Type (T)
10138 Set_Corresponding_Record_Type (Def_Id,
10139 Corresponding_Record_Type (T));
10141 Set_Direct_Primitive_Operations (Def_Id,
10142 Direct_Primitive_Operations (T));
10145 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
10148 -- Subtypes introduced by component declarations do not need to be
10149 -- marked as delayed, and do not get freeze nodes, because the semantics
10150 -- verifies that the parents of the subtypes are frozen before the
10151 -- enclosing record is frozen.
10153 if not Is_Type (Scope (Def_Id)) then
10154 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10156 if Is_Private_Type (T)
10157 and then Present (Full_View (T))
10159 Conditional_Delay (Def_Id, Full_View (T));
10161 Conditional_Delay (Def_Id, T);
10165 if Is_Record_Type (T) then
10166 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
10169 and then not Is_Empty_Elmt_List (Elist)
10170 and then not For_Access
10172 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
10173 elsif not For_Access then
10174 Set_Cloned_Subtype (Def_Id, T);
10177 end Build_Discriminated_Subtype;
10179 ---------------------------
10180 -- Build_Itype_Reference --
10181 ---------------------------
10183 procedure Build_Itype_Reference
10187 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
10190 -- Itype references are only created for use by the back-end
10192 if Inside_A_Generic then
10195 Set_Itype (IR, Ityp);
10196 Insert_After (Nod, IR);
10198 end Build_Itype_Reference;
10200 ------------------------
10201 -- Build_Scalar_Bound --
10202 ------------------------
10204 function Build_Scalar_Bound
10207 Der_T : Entity_Id) return Node_Id
10209 New_Bound : Entity_Id;
10212 -- Note: not clear why this is needed, how can the original bound
10213 -- be unanalyzed at this point? and if it is, what business do we
10214 -- have messing around with it? and why is the base type of the
10215 -- parent type the right type for the resolution. It probably is
10216 -- not. It is OK for the new bound we are creating, but not for
10217 -- the old one??? Still if it never happens, no problem.
10219 Analyze_And_Resolve (Bound, Base_Type (Par_T));
10221 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
10222 New_Bound := New_Copy (Bound);
10223 Set_Etype (New_Bound, Der_T);
10224 Set_Analyzed (New_Bound);
10226 elsif Is_Entity_Name (Bound) then
10227 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
10229 -- The following is almost certainly wrong. What business do we have
10230 -- relocating a node (Bound) that is presumably still attached to
10231 -- the tree elsewhere???
10234 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
10237 Set_Etype (New_Bound, Der_T);
10239 end Build_Scalar_Bound;
10241 --------------------------------
10242 -- Build_Underlying_Full_View --
10243 --------------------------------
10245 procedure Build_Underlying_Full_View
10250 Loc : constant Source_Ptr := Sloc (N);
10251 Subt : constant Entity_Id :=
10252 Make_Defining_Identifier
10253 (Loc, New_External_Name (Chars (Typ), 'S'));
10260 procedure Set_Discriminant_Name (Id : Node_Id);
10261 -- If the derived type has discriminants, they may rename discriminants
10262 -- of the parent. When building the full view of the parent, we need to
10263 -- recover the names of the original discriminants if the constraint is
10264 -- given by named associations.
10266 ---------------------------
10267 -- Set_Discriminant_Name --
10268 ---------------------------
10270 procedure Set_Discriminant_Name (Id : Node_Id) is
10274 Set_Original_Discriminant (Id, Empty);
10276 if Has_Discriminants (Typ) then
10277 Disc := First_Discriminant (Typ);
10278 while Present (Disc) loop
10279 if Chars (Disc) = Chars (Id)
10280 and then Present (Corresponding_Discriminant (Disc))
10282 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
10284 Next_Discriminant (Disc);
10287 end Set_Discriminant_Name;
10289 -- Start of processing for Build_Underlying_Full_View
10292 if Nkind (N) = N_Full_Type_Declaration then
10293 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
10295 elsif Nkind (N) = N_Subtype_Declaration then
10296 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
10298 elsif Nkind (N) = N_Component_Declaration then
10301 (Constraint (Subtype_Indication (Component_Definition (N))));
10304 raise Program_Error;
10307 C := First (Constraints (Constr));
10308 while Present (C) loop
10309 if Nkind (C) = N_Discriminant_Association then
10310 Id := First (Selector_Names (C));
10311 while Present (Id) loop
10312 Set_Discriminant_Name (Id);
10321 Make_Subtype_Declaration (Loc,
10322 Defining_Identifier => Subt,
10323 Subtype_Indication =>
10324 Make_Subtype_Indication (Loc,
10325 Subtype_Mark => New_Occurrence_Of (Par, Loc),
10326 Constraint => New_Copy_Tree (Constr)));
10328 -- If this is a component subtype for an outer itype, it is not
10329 -- a list member, so simply set the parent link for analysis: if
10330 -- the enclosing type does not need to be in a declarative list,
10331 -- neither do the components.
10333 if Is_List_Member (N)
10334 and then Nkind (N) /= N_Component_Declaration
10336 Insert_Before (N, Indic);
10338 Set_Parent (Indic, Parent (N));
10342 Set_Underlying_Full_View (Typ, Full_View (Subt));
10343 Set_Is_Underlying_Full_View (Full_View (Subt));
10344 end Build_Underlying_Full_View;
10346 -------------------------------
10347 -- Check_Abstract_Overriding --
10348 -------------------------------
10350 procedure Check_Abstract_Overriding (T : Entity_Id) is
10351 Alias_Subp : Entity_Id;
10353 Op_List : Elist_Id;
10355 Type_Def : Node_Id;
10357 procedure Check_Pragma_Implemented (Subp : Entity_Id);
10358 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
10359 -- which has pragma Implemented already set. Check whether Subp's entity
10360 -- kind conforms to the implementation kind of the overridden routine.
10362 procedure Check_Pragma_Implemented
10364 Iface_Subp : Entity_Id);
10365 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
10366 -- Iface_Subp and both entities have pragma Implemented already set on
10367 -- them. Check whether the two implementation kinds are conforming.
10369 procedure Inherit_Pragma_Implemented
10371 Iface_Subp : Entity_Id);
10372 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
10373 -- subprogram Iface_Subp which has been marked by pragma Implemented.
10374 -- Propagate the implementation kind of Iface_Subp to Subp.
10376 ------------------------------
10377 -- Check_Pragma_Implemented --
10378 ------------------------------
10380 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
10381 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
10382 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
10383 Subp_Alias : constant Entity_Id := Alias (Subp);
10384 Contr_Typ : Entity_Id;
10385 Impl_Subp : Entity_Id;
10388 -- Subp must have an alias since it is a hidden entity used to link
10389 -- an interface subprogram to its overriding counterpart.
10391 pragma Assert (Present (Subp_Alias));
10393 -- Handle aliases to synchronized wrappers
10395 Impl_Subp := Subp_Alias;
10397 if Is_Primitive_Wrapper (Impl_Subp) then
10398 Impl_Subp := Wrapped_Entity (Impl_Subp);
10401 -- Extract the type of the controlling formal
10403 Contr_Typ := Etype (First_Formal (Subp_Alias));
10405 if Is_Concurrent_Record_Type (Contr_Typ) then
10406 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
10409 -- An interface subprogram whose implementation kind is By_Entry must
10410 -- be implemented by an entry.
10412 if Impl_Kind = Name_By_Entry
10413 and then Ekind (Impl_Subp) /= E_Entry
10415 Error_Msg_Node_2 := Iface_Alias;
10417 ("type & must implement abstract subprogram & with an entry",
10418 Subp_Alias, Contr_Typ);
10420 elsif Impl_Kind = Name_By_Protected_Procedure then
10422 -- An interface subprogram whose implementation kind is By_
10423 -- Protected_Procedure cannot be implemented by a primitive
10424 -- procedure of a task type.
10426 if Ekind (Contr_Typ) /= E_Protected_Type then
10427 Error_Msg_Node_2 := Contr_Typ;
10429 ("interface subprogram & cannot be implemented by a " &
10430 "primitive procedure of task type &", Subp_Alias,
10433 -- An interface subprogram whose implementation kind is By_
10434 -- Protected_Procedure must be implemented by a procedure.
10436 elsif Ekind (Impl_Subp) /= E_Procedure then
10437 Error_Msg_Node_2 := Iface_Alias;
10439 ("type & must implement abstract subprogram & with a " &
10440 "procedure", Subp_Alias, Contr_Typ);
10442 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10443 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10445 Error_Msg_Name_1 := Impl_Kind;
10447 ("overriding operation& must have synchronization%",
10451 -- If primitive has Optional synchronization, overriding operation
10452 -- must match if it has an explicit synchronization..
10454 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10455 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10457 Error_Msg_Name_1 := Impl_Kind;
10459 ("overriding operation& must have syncrhonization%",
10462 end Check_Pragma_Implemented;
10464 ------------------------------
10465 -- Check_Pragma_Implemented --
10466 ------------------------------
10468 procedure Check_Pragma_Implemented
10470 Iface_Subp : Entity_Id)
10472 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10473 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10476 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10477 -- and overriding subprogram are different. In general this is an
10478 -- error except when the implementation kind of the overridden
10479 -- subprograms is By_Any or Optional.
10481 if Iface_Kind /= Subp_Kind
10482 and then Iface_Kind /= Name_By_Any
10483 and then Iface_Kind /= Name_Optional
10485 if Iface_Kind = Name_By_Entry then
10487 ("incompatible implementation kind, overridden subprogram " &
10488 "is marked By_Entry", Subp);
10491 ("incompatible implementation kind, overridden subprogram " &
10492 "is marked By_Protected_Procedure", Subp);
10495 end Check_Pragma_Implemented;
10497 --------------------------------
10498 -- Inherit_Pragma_Implemented --
10499 --------------------------------
10501 procedure Inherit_Pragma_Implemented
10503 Iface_Subp : Entity_Id)
10505 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10506 Loc : constant Source_Ptr := Sloc (Subp);
10507 Impl_Prag : Node_Id;
10510 -- Since the implementation kind is stored as a representation item
10511 -- rather than a flag, create a pragma node.
10515 Chars => Name_Implemented,
10516 Pragma_Argument_Associations => New_List (
10517 Make_Pragma_Argument_Association (Loc,
10518 Expression => New_Occurrence_Of (Subp, Loc)),
10520 Make_Pragma_Argument_Association (Loc,
10521 Expression => Make_Identifier (Loc, Iface_Kind))));
10523 -- The pragma doesn't need to be analyzed because it is internally
10524 -- built. It is safe to directly register it as a rep item since we
10525 -- are only interested in the characters of the implementation kind.
10527 Record_Rep_Item (Subp, Impl_Prag);
10528 end Inherit_Pragma_Implemented;
10530 -- Start of processing for Check_Abstract_Overriding
10533 Op_List := Primitive_Operations (T);
10535 -- Loop to check primitive operations
10537 Elmt := First_Elmt (Op_List);
10538 while Present (Elmt) loop
10539 Subp := Node (Elmt);
10540 Alias_Subp := Alias (Subp);
10542 -- Inherited subprograms are identified by the fact that they do not
10543 -- come from source, and the associated source location is the
10544 -- location of the first subtype of the derived type.
10546 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10547 -- subprograms that "require overriding".
10549 -- Special exception, do not complain about failure to override the
10550 -- stream routines _Input and _Output, as well as the primitive
10551 -- operations used in dispatching selects since we always provide
10552 -- automatic overridings for these subprograms.
10554 -- The partial view of T may have been a private extension, for
10555 -- which inherited functions dispatching on result are abstract.
10556 -- If the full view is a null extension, there is no need for
10557 -- overriding in Ada 2005, but wrappers need to be built for them
10558 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10560 if Is_Null_Extension (T)
10561 and then Has_Controlling_Result (Subp)
10562 and then Ada_Version >= Ada_2005
10563 and then Present (Alias_Subp)
10564 and then not Comes_From_Source (Subp)
10565 and then not Is_Abstract_Subprogram (Alias_Subp)
10566 and then not Is_Access_Type (Etype (Subp))
10570 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10571 -- processing because this check is done with the aliased
10574 elsif Present (Interface_Alias (Subp)) then
10577 elsif (Is_Abstract_Subprogram (Subp)
10578 or else Requires_Overriding (Subp)
10580 (Has_Controlling_Result (Subp)
10581 and then Present (Alias_Subp)
10582 and then not Comes_From_Source (Subp)
10583 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10584 and then not Is_TSS (Subp, TSS_Stream_Input)
10585 and then not Is_TSS (Subp, TSS_Stream_Output)
10586 and then not Is_Abstract_Type (T)
10587 and then not Is_Predefined_Interface_Primitive (Subp)
10589 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10590 -- with abstract interface types because the check will be done
10591 -- with the aliased entity (otherwise we generate a duplicated
10594 and then not Present (Interface_Alias (Subp))
10596 if Present (Alias_Subp) then
10598 -- Only perform the check for a derived subprogram when the
10599 -- type has an explicit record extension. This avoids incorrect
10600 -- flagging of abstract subprograms for the case of a type
10601 -- without an extension that is derived from a formal type
10602 -- with a tagged actual (can occur within a private part).
10604 -- Ada 2005 (AI-391): In the case of an inherited function with
10605 -- a controlling result of the type, the rule does not apply if
10606 -- the type is a null extension (unless the parent function
10607 -- itself is abstract, in which case the function must still be
10608 -- be overridden). The expander will generate an overriding
10609 -- wrapper function calling the parent subprogram (see
10610 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10612 Type_Def := Type_Definition (Parent (T));
10614 if Nkind (Type_Def) = N_Derived_Type_Definition
10615 and then Present (Record_Extension_Part (Type_Def))
10617 (Ada_Version < Ada_2005
10618 or else not Is_Null_Extension (T)
10619 or else Ekind (Subp) = E_Procedure
10620 or else not Has_Controlling_Result (Subp)
10621 or else Is_Abstract_Subprogram (Alias_Subp)
10622 or else Requires_Overriding (Subp)
10623 or else Is_Access_Type (Etype (Subp)))
10625 -- Avoid reporting error in case of abstract predefined
10626 -- primitive inherited from interface type because the
10627 -- body of internally generated predefined primitives
10628 -- of tagged types are generated later by Freeze_Type
10630 if Is_Interface (Root_Type (T))
10631 and then Is_Abstract_Subprogram (Subp)
10632 and then Is_Predefined_Dispatching_Operation (Subp)
10633 and then not Comes_From_Source (Ultimate_Alias (Subp))
10637 -- A null extension is not obliged to override an inherited
10638 -- procedure subject to pragma Extensions_Visible with value
10639 -- False and at least one controlling OUT parameter
10640 -- (SPARK RM 6.1.7(6)).
10642 elsif Is_Null_Extension (T)
10643 and then Is_EVF_Procedure (Subp)
10649 ("type must be declared abstract or & overridden",
10652 -- Traverse the whole chain of aliased subprograms to
10653 -- complete the error notification. This is especially
10654 -- useful for traceability of the chain of entities when
10655 -- the subprogram corresponds with an interface
10656 -- subprogram (which may be defined in another package).
10658 if Present (Alias_Subp) then
10664 while Present (Alias (E)) loop
10666 -- Avoid reporting redundant errors on entities
10667 -- inherited from interfaces
10669 if Sloc (E) /= Sloc (T) then
10670 Error_Msg_Sloc := Sloc (E);
10672 ("\& has been inherited #", T, Subp);
10678 Error_Msg_Sloc := Sloc (E);
10680 -- AI05-0068: report if there is an overriding
10681 -- non-abstract subprogram that is invisible.
10684 and then not Is_Abstract_Subprogram (E)
10687 ("\& subprogram# is not visible",
10690 -- Clarify the case where a non-null extension must
10691 -- override inherited procedure subject to pragma
10692 -- Extensions_Visible with value False and at least
10693 -- one controlling OUT param.
10695 elsif Is_EVF_Procedure (E) then
10697 ("\& # is subject to Extensions_Visible False",
10702 ("\& has been inherited from subprogram #",
10709 -- Ada 2005 (AI-345): Protected or task type implementing
10710 -- abstract interfaces.
10712 elsif Is_Concurrent_Record_Type (T)
10713 and then Present (Interfaces (T))
10715 -- There is no need to check here RM 9.4(11.9/3) since we
10716 -- are processing the corresponding record type and the
10717 -- mode of the overriding subprograms was verified by
10718 -- Check_Conformance when the corresponding concurrent
10719 -- type declaration was analyzed.
10722 ("interface subprogram & must be overridden", T, Subp);
10724 -- Examine primitive operations of synchronized type to find
10725 -- homonyms that have the wrong profile.
10731 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10732 while Present (Prim) loop
10733 if Chars (Prim) = Chars (Subp) then
10735 ("profile is not type conformant with prefixed "
10736 & "view profile of inherited operation&",
10740 Next_Entity (Prim);
10746 Error_Msg_Node_2 := T;
10748 ("abstract subprogram& not allowed for type&", Subp);
10750 -- Also post unconditional warning on the type (unconditional
10751 -- so that if there are more than one of these cases, we get
10752 -- them all, and not just the first one).
10754 Error_Msg_Node_2 := Subp;
10755 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10758 -- A subprogram subject to pragma Extensions_Visible with value
10759 -- "True" cannot override a subprogram subject to the same pragma
10760 -- with value "False" (SPARK RM 6.1.7(5)).
10762 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10763 and then Present (Overridden_Operation (Subp))
10764 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10765 Extensions_Visible_False
10767 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10769 ("subprogram & with Extensions_Visible True cannot override "
10770 & "subprogram # with Extensions_Visible False", Subp);
10773 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10775 -- Subp is an expander-generated procedure which maps an interface
10776 -- alias to a protected wrapper. The interface alias is flagged by
10777 -- pragma Implemented. Ensure that Subp is a procedure when the
10778 -- implementation kind is By_Protected_Procedure or an entry when
10781 if Ada_Version >= Ada_2012
10782 and then Is_Hidden (Subp)
10783 and then Present (Interface_Alias (Subp))
10784 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10786 Check_Pragma_Implemented (Subp);
10789 -- Subp is an interface primitive which overrides another interface
10790 -- primitive marked with pragma Implemented.
10792 if Ada_Version >= Ada_2012
10793 and then Present (Overridden_Operation (Subp))
10794 and then Has_Rep_Pragma
10795 (Overridden_Operation (Subp), Name_Implemented)
10797 -- If the overriding routine is also marked by Implemented, check
10798 -- that the two implementation kinds are conforming.
10800 if Has_Rep_Pragma (Subp, Name_Implemented) then
10801 Check_Pragma_Implemented
10803 Iface_Subp => Overridden_Operation (Subp));
10805 -- Otherwise the overriding routine inherits the implementation
10806 -- kind from the overridden subprogram.
10809 Inherit_Pragma_Implemented
10811 Iface_Subp => Overridden_Operation (Subp));
10815 -- If the operation is a wrapper for a synchronized primitive, it
10816 -- may be called indirectly through a dispatching select. We assume
10817 -- that it will be referenced elsewhere indirectly, and suppress
10818 -- warnings about an unused entity.
10820 if Is_Primitive_Wrapper (Subp)
10821 and then Present (Wrapped_Entity (Subp))
10823 Set_Referenced (Wrapped_Entity (Subp));
10828 end Check_Abstract_Overriding;
10830 ------------------------------------------------
10831 -- Check_Access_Discriminant_Requires_Limited --
10832 ------------------------------------------------
10834 procedure Check_Access_Discriminant_Requires_Limited
10839 -- A discriminant_specification for an access discriminant shall appear
10840 -- only in the declaration for a task or protected type, or for a type
10841 -- with the reserved word 'limited' in its definition or in one of its
10842 -- ancestors (RM 3.7(10)).
10844 -- AI-0063: The proper condition is that type must be immutably limited,
10845 -- or else be a partial view.
10847 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10848 if Is_Limited_View (Current_Scope)
10850 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10851 and then Limited_Present (Parent (Current_Scope)))
10857 ("access discriminants allowed only for limited types", Loc);
10860 end Check_Access_Discriminant_Requires_Limited;
10862 -----------------------------------
10863 -- Check_Aliased_Component_Types --
10864 -----------------------------------
10866 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10870 -- ??? Also need to check components of record extensions, but not
10871 -- components of protected types (which are always limited).
10873 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10874 -- types to be unconstrained. This is safe because it is illegal to
10875 -- create access subtypes to such types with explicit discriminant
10878 if not Is_Limited_Type (T) then
10879 if Ekind (T) = E_Record_Type then
10880 C := First_Component (T);
10881 while Present (C) loop
10883 and then Has_Discriminants (Etype (C))
10884 and then not Is_Constrained (Etype (C))
10885 and then not In_Instance_Body
10886 and then Ada_Version < Ada_2005
10889 ("aliased component must be constrained (RM 3.6(11))",
10893 Next_Component (C);
10896 elsif Ekind (T) = E_Array_Type then
10897 if Has_Aliased_Components (T)
10898 and then Has_Discriminants (Component_Type (T))
10899 and then not Is_Constrained (Component_Type (T))
10900 and then not In_Instance_Body
10901 and then Ada_Version < Ada_2005
10904 ("aliased component type must be constrained (RM 3.6(11))",
10909 end Check_Aliased_Component_Types;
10911 ---------------------------------------
10912 -- Check_Anonymous_Access_Components --
10913 ---------------------------------------
10915 procedure Check_Anonymous_Access_Components
10916 (Typ_Decl : Node_Id;
10919 Comp_List : Node_Id)
10921 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10922 Anon_Access : Entity_Id;
10925 Comp_Def : Node_Id;
10927 Type_Def : Node_Id;
10929 procedure Build_Incomplete_Type_Declaration;
10930 -- If the record type contains components that include an access to the
10931 -- current record, then create an incomplete type declaration for the
10932 -- record, to be used as the designated type of the anonymous access.
10933 -- This is done only once, and only if there is no previous partial
10934 -- view of the type.
10936 function Designates_T (Subt : Node_Id) return Boolean;
10937 -- Check whether a node designates the enclosing record type, or 'Class
10940 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10941 -- Check whether an access definition includes a reference to
10942 -- the enclosing record type. The reference can be a subtype mark
10943 -- in the access definition itself, a 'Class attribute reference, or
10944 -- recursively a reference appearing in a parameter specification
10945 -- or result definition of an access_to_subprogram definition.
10947 --------------------------------------
10948 -- Build_Incomplete_Type_Declaration --
10949 --------------------------------------
10951 procedure Build_Incomplete_Type_Declaration is
10956 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10957 -- it's "is new ... with record" or else "is tagged record ...".
10959 Is_Tagged : constant Boolean :=
10960 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10962 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10964 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10965 and then Tagged_Present (Type_Definition (Typ_Decl)));
10968 -- If there is a previous partial view, no need to create a new one
10969 -- If the partial view, given by Prev, is incomplete, If Prev is
10970 -- a private declaration, full declaration is flagged accordingly.
10972 if Prev /= Typ then
10974 Make_Class_Wide_Type (Prev);
10975 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10976 Set_Etype (Class_Wide_Type (Typ), Typ);
10981 elsif Has_Private_Declaration (Typ) then
10983 -- If we refer to T'Class inside T, and T is the completion of a
10984 -- private type, then make sure the class-wide type exists.
10987 Make_Class_Wide_Type (Typ);
10992 -- If there was a previous anonymous access type, the incomplete
10993 -- type declaration will have been created already.
10995 elsif Present (Current_Entity (Typ))
10996 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10997 and then Full_View (Current_Entity (Typ)) = Typ
11000 and then Comes_From_Source (Current_Entity (Typ))
11001 and then not Is_Tagged_Type (Current_Entity (Typ))
11003 Make_Class_Wide_Type (Typ);
11005 ("incomplete view of tagged type should be declared tagged??",
11006 Parent (Current_Entity (Typ)));
11011 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
11012 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
11014 -- Type has already been inserted into the current scope. Remove
11015 -- it, and add incomplete declaration for type, so that subsequent
11016 -- anonymous access types can use it. The entity is unchained from
11017 -- the homonym list and from immediate visibility. After analysis,
11018 -- the entity in the incomplete declaration becomes immediately
11019 -- visible in the record declaration that follows.
11021 H := Current_Entity (Typ);
11024 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
11027 and then Homonym (H) /= Typ
11029 H := Homonym (Typ);
11032 Set_Homonym (H, Homonym (Typ));
11035 Insert_Before (Typ_Decl, Decl);
11037 Set_Full_View (Inc_T, Typ);
11041 -- Create a common class-wide type for both views, and set the
11042 -- Etype of the class-wide type to the full view.
11044 Make_Class_Wide_Type (Inc_T);
11045 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
11046 Set_Etype (Class_Wide_Type (Typ), Typ);
11049 end Build_Incomplete_Type_Declaration;
11055 function Designates_T (Subt : Node_Id) return Boolean is
11056 Type_Id : constant Name_Id := Chars (Typ);
11058 function Names_T (Nam : Node_Id) return Boolean;
11059 -- The record type has not been introduced in the current scope
11060 -- yet, so we must examine the name of the type itself, either
11061 -- an identifier T, or an expanded name of the form P.T, where
11062 -- P denotes the current scope.
11068 function Names_T (Nam : Node_Id) return Boolean is
11070 if Nkind (Nam) = N_Identifier then
11071 return Chars (Nam) = Type_Id;
11073 elsif Nkind (Nam) = N_Selected_Component then
11074 if Chars (Selector_Name (Nam)) = Type_Id then
11075 if Nkind (Prefix (Nam)) = N_Identifier then
11076 return Chars (Prefix (Nam)) = Chars (Current_Scope);
11078 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
11079 return Chars (Selector_Name (Prefix (Nam))) =
11080 Chars (Current_Scope);
11094 -- Start of processing for Designates_T
11097 if Nkind (Subt) = N_Identifier then
11098 return Chars (Subt) = Type_Id;
11100 -- Reference can be through an expanded name which has not been
11101 -- analyzed yet, and which designates enclosing scopes.
11103 elsif Nkind (Subt) = N_Selected_Component then
11104 if Names_T (Subt) then
11107 -- Otherwise it must denote an entity that is already visible.
11108 -- The access definition may name a subtype of the enclosing
11109 -- type, if there is a previous incomplete declaration for it.
11112 Find_Selected_Component (Subt);
11114 Is_Entity_Name (Subt)
11115 and then Scope (Entity (Subt)) = Current_Scope
11117 (Chars (Base_Type (Entity (Subt))) = Type_Id
11119 (Is_Class_Wide_Type (Entity (Subt))
11121 Chars (Etype (Base_Type (Entity (Subt)))) =
11125 -- A reference to the current type may appear as the prefix of
11126 -- a 'Class attribute.
11128 elsif Nkind (Subt) = N_Attribute_Reference
11129 and then Attribute_Name (Subt) = Name_Class
11131 return Names_T (Prefix (Subt));
11142 function Mentions_T (Acc_Def : Node_Id) return Boolean is
11143 Param_Spec : Node_Id;
11145 Acc_Subprg : constant Node_Id :=
11146 Access_To_Subprogram_Definition (Acc_Def);
11149 if No (Acc_Subprg) then
11150 return Designates_T (Subtype_Mark (Acc_Def));
11153 -- Component is an access_to_subprogram: examine its formals,
11154 -- and result definition in the case of an access_to_function.
11156 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
11157 while Present (Param_Spec) loop
11158 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
11159 and then Mentions_T (Parameter_Type (Param_Spec))
11163 elsif Designates_T (Parameter_Type (Param_Spec)) then
11170 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
11171 if Nkind (Result_Definition (Acc_Subprg)) =
11172 N_Access_Definition
11174 return Mentions_T (Result_Definition (Acc_Subprg));
11176 return Designates_T (Result_Definition (Acc_Subprg));
11183 -- Start of processing for Check_Anonymous_Access_Components
11186 if No (Comp_List) then
11190 Comp := First (Component_Items (Comp_List));
11191 while Present (Comp) loop
11192 if Nkind (Comp) = N_Component_Declaration
11194 (Access_Definition (Component_Definition (Comp)))
11196 Mentions_T (Access_Definition (Component_Definition (Comp)))
11198 Comp_Def := Component_Definition (Comp);
11200 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
11202 Build_Incomplete_Type_Declaration;
11203 Anon_Access := Make_Temporary (Loc, 'S');
11205 -- Create a declaration for the anonymous access type: either
11206 -- an access_to_object or an access_to_subprogram.
11208 if Present (Acc_Def) then
11209 if Nkind (Acc_Def) = N_Access_Function_Definition then
11211 Make_Access_Function_Definition (Loc,
11212 Parameter_Specifications =>
11213 Parameter_Specifications (Acc_Def),
11214 Result_Definition => Result_Definition (Acc_Def));
11217 Make_Access_Procedure_Definition (Loc,
11218 Parameter_Specifications =>
11219 Parameter_Specifications (Acc_Def));
11224 Make_Access_To_Object_Definition (Loc,
11225 Subtype_Indication =>
11227 (Subtype_Mark (Access_Definition (Comp_Def))));
11229 Set_Constant_Present
11230 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
11232 (Type_Def, All_Present (Access_Definition (Comp_Def)));
11235 Set_Null_Exclusion_Present
11237 Null_Exclusion_Present (Access_Definition (Comp_Def)));
11240 Make_Full_Type_Declaration (Loc,
11241 Defining_Identifier => Anon_Access,
11242 Type_Definition => Type_Def);
11244 Insert_Before (Typ_Decl, Decl);
11247 -- If an access to subprogram, create the extra formals
11249 if Present (Acc_Def) then
11250 Create_Extra_Formals (Designated_Type (Anon_Access));
11252 -- If an access to object, preserve entity of designated type,
11253 -- for ASIS use, before rewriting the component definition.
11260 Desig := Entity (Subtype_Indication (Type_Def));
11262 -- If the access definition is to the current record,
11263 -- the visible entity at this point is an incomplete
11264 -- type. Retrieve the full view to simplify ASIS queries
11266 if Ekind (Desig) = E_Incomplete_Type then
11267 Desig := Full_View (Desig);
11271 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
11276 Make_Component_Definition (Loc,
11277 Subtype_Indication =>
11278 New_Occurrence_Of (Anon_Access, Loc)));
11280 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
11281 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
11283 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
11286 Set_Is_Local_Anonymous_Access (Anon_Access);
11292 if Present (Variant_Part (Comp_List)) then
11296 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
11297 while Present (V) loop
11298 Check_Anonymous_Access_Components
11299 (Typ_Decl, Typ, Prev, Component_List (V));
11300 Next_Non_Pragma (V);
11304 end Check_Anonymous_Access_Components;
11306 ----------------------
11307 -- Check_Completion --
11308 ----------------------
11310 procedure Check_Completion (Body_Id : Node_Id := Empty) is
11313 procedure Post_Error;
11314 -- Post error message for lack of completion for entity E
11320 procedure Post_Error is
11321 procedure Missing_Body;
11322 -- Output missing body message
11328 procedure Missing_Body is
11330 -- Spec is in same unit, so we can post on spec
11332 if In_Same_Source_Unit (Body_Id, E) then
11333 Error_Msg_N ("missing body for &", E);
11335 -- Spec is in a separate unit, so we have to post on the body
11338 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
11342 -- Start of processing for Post_Error
11345 if not Comes_From_Source (E) then
11346 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
11348 -- It may be an anonymous protected type created for a
11349 -- single variable. Post error on variable, if present.
11355 Var := First_Entity (Current_Scope);
11356 while Present (Var) loop
11357 exit when Etype (Var) = E
11358 and then Comes_From_Source (Var);
11363 if Present (Var) then
11370 -- If a generated entity has no completion, then either previous
11371 -- semantic errors have disabled the expansion phase, or else we had
11372 -- missing subunits, or else we are compiling without expansion,
11373 -- or else something is very wrong.
11375 if not Comes_From_Source (E) then
11377 (Serious_Errors_Detected > 0
11378 or else Configurable_Run_Time_Violations > 0
11379 or else Subunits_Missing
11380 or else not Expander_Active);
11383 -- Here for source entity
11386 -- Here if no body to post the error message, so we post the error
11387 -- on the declaration that has no completion. This is not really
11388 -- the right place to post it, think about this later ???
11390 if No (Body_Id) then
11391 if Is_Type (E) then
11393 ("missing full declaration for }", Parent (E), E);
11395 Error_Msg_NE ("missing body for &", Parent (E), E);
11398 -- Package body has no completion for a declaration that appears
11399 -- in the corresponding spec. Post error on the body, with a
11400 -- reference to the non-completed declaration.
11403 Error_Msg_Sloc := Sloc (E);
11405 if Is_Type (E) then
11406 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
11408 elsif Is_Overloadable (E)
11409 and then Current_Entity_In_Scope (E) /= E
11411 -- It may be that the completion is mistyped and appears as
11412 -- a distinct overloading of the entity.
11415 Candidate : constant Entity_Id :=
11416 Current_Entity_In_Scope (E);
11417 Decl : constant Node_Id :=
11418 Unit_Declaration_Node (Candidate);
11421 if Is_Overloadable (Candidate)
11422 and then Ekind (Candidate) = Ekind (E)
11423 and then Nkind (Decl) = N_Subprogram_Body
11424 and then Acts_As_Spec (Decl)
11426 Check_Type_Conformant (Candidate, E);
11442 Pack_Id : constant Entity_Id := Current_Scope;
11444 -- Start of processing for Check_Completion
11447 E := First_Entity (Pack_Id);
11448 while Present (E) loop
11449 if Is_Intrinsic_Subprogram (E) then
11452 -- The following situation requires special handling: a child unit
11453 -- that appears in the context clause of the body of its parent:
11455 -- procedure Parent.Child (...);
11457 -- with Parent.Child;
11458 -- package body Parent is
11460 -- Here Parent.Child appears as a local entity, but should not be
11461 -- flagged as requiring completion, because it is a compilation
11464 -- Ignore missing completion for a subprogram that does not come from
11465 -- source (including the _Call primitive operation of RAS types,
11466 -- which has to have the flag Comes_From_Source for other purposes):
11467 -- we assume that the expander will provide the missing completion.
11468 -- In case of previous errors, other expansion actions that provide
11469 -- bodies for null procedures with not be invoked, so inhibit message
11472 -- Note that E_Operator is not in the list that follows, because
11473 -- this kind is reserved for predefined operators, that are
11474 -- intrinsic and do not need completion.
11476 elsif Ekind_In (E, E_Function,
11478 E_Generic_Function,
11479 E_Generic_Procedure)
11481 if Has_Completion (E) then
11484 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11487 elsif Is_Subprogram (E)
11488 and then (not Comes_From_Source (E)
11489 or else Chars (E) = Name_uCall)
11494 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11498 elsif Nkind (Parent (E)) = N_Procedure_Specification
11499 and then Null_Present (Parent (E))
11500 and then Serious_Errors_Detected > 0
11508 elsif Is_Entry (E) then
11509 if not Has_Completion (E) and then
11510 (Ekind (Scope (E)) = E_Protected_Object
11511 or else Ekind (Scope (E)) = E_Protected_Type)
11516 elsif Is_Package_Or_Generic_Package (E) then
11517 if Unit_Requires_Body (E) then
11518 if not Has_Completion (E)
11519 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11525 elsif not Is_Child_Unit (E) then
11526 May_Need_Implicit_Body (E);
11529 -- A formal incomplete type (Ada 2012) does not require a completion;
11530 -- other incomplete type declarations do.
11532 elsif Ekind (E) = E_Incomplete_Type
11533 and then No (Underlying_Type (E))
11534 and then not Is_Generic_Type (E)
11538 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11539 and then not Has_Completion (E)
11543 -- A single task declared in the current scope is a constant, verify
11544 -- that the body of its anonymous type is in the same scope. If the
11545 -- task is defined elsewhere, this may be a renaming declaration for
11546 -- which no completion is needed.
11548 elsif Ekind (E) = E_Constant
11549 and then Ekind (Etype (E)) = E_Task_Type
11550 and then not Has_Completion (Etype (E))
11551 and then Scope (Etype (E)) = Current_Scope
11555 elsif Ekind (E) = E_Protected_Object
11556 and then not Has_Completion (Etype (E))
11560 elsif Ekind (E) = E_Record_Type then
11561 if Is_Tagged_Type (E) then
11562 Check_Abstract_Overriding (E);
11563 Check_Conventions (E);
11566 Check_Aliased_Component_Types (E);
11568 elsif Ekind (E) = E_Array_Type then
11569 Check_Aliased_Component_Types (E);
11575 end Check_Completion;
11577 ------------------------------------
11578 -- Check_CPP_Type_Has_No_Defaults --
11579 ------------------------------------
11581 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11582 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11587 -- Obtain the component list
11589 if Nkind (Tdef) = N_Record_Definition then
11590 Clist := Component_List (Tdef);
11591 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11592 Clist := Component_List (Record_Extension_Part (Tdef));
11595 -- Check all components to ensure no default expressions
11597 if Present (Clist) then
11598 Comp := First (Component_Items (Clist));
11599 while Present (Comp) loop
11600 if Present (Expression (Comp)) then
11602 ("component of imported 'C'P'P type cannot have "
11603 & "default expression", Expression (Comp));
11609 end Check_CPP_Type_Has_No_Defaults;
11611 ----------------------------
11612 -- Check_Delta_Expression --
11613 ----------------------------
11615 procedure Check_Delta_Expression (E : Node_Id) is
11617 if not (Is_Real_Type (Etype (E))) then
11618 Wrong_Type (E, Any_Real);
11620 elsif not Is_OK_Static_Expression (E) then
11621 Flag_Non_Static_Expr
11622 ("non-static expression used for delta value!", E);
11624 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11625 Error_Msg_N ("delta expression must be positive", E);
11631 -- If any of above errors occurred, then replace the incorrect
11632 -- expression by the real 0.1, which should prevent further errors.
11635 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11636 Analyze_And_Resolve (E, Standard_Float);
11637 end Check_Delta_Expression;
11639 -----------------------------
11640 -- Check_Digits_Expression --
11641 -----------------------------
11643 procedure Check_Digits_Expression (E : Node_Id) is
11645 if not (Is_Integer_Type (Etype (E))) then
11646 Wrong_Type (E, Any_Integer);
11648 elsif not Is_OK_Static_Expression (E) then
11649 Flag_Non_Static_Expr
11650 ("non-static expression used for digits value!", E);
11652 elsif Expr_Value (E) <= 0 then
11653 Error_Msg_N ("digits value must be greater than zero", E);
11659 -- If any of above errors occurred, then replace the incorrect
11660 -- expression by the integer 1, which should prevent further errors.
11662 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11663 Analyze_And_Resolve (E, Standard_Integer);
11665 end Check_Digits_Expression;
11667 --------------------------
11668 -- Check_Initialization --
11669 --------------------------
11671 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11673 -- Special processing for limited types
11675 if Is_Limited_Type (T)
11676 and then not In_Instance
11677 and then not In_Inlined_Body
11679 if not OK_For_Limited_Init (T, Exp) then
11681 -- In GNAT mode, this is just a warning, to allow it to be evilly
11682 -- turned off. Otherwise it is a real error.
11686 ("??cannot initialize entities of limited type!", Exp);
11688 elsif Ada_Version < Ada_2005 then
11690 -- The side effect removal machinery may generate illegal Ada
11691 -- code to avoid the usage of access types and 'reference in
11692 -- SPARK mode. Since this is legal code with respect to theorem
11693 -- proving, do not emit the error.
11696 and then Nkind (Exp) = N_Function_Call
11697 and then Nkind (Parent (Exp)) = N_Object_Declaration
11698 and then not Comes_From_Source
11699 (Defining_Identifier (Parent (Exp)))
11705 ("cannot initialize entities of limited type", Exp);
11706 Explain_Limited_Type (T, Exp);
11710 -- Specialize error message according to kind of illegal
11711 -- initial expression.
11713 if Nkind (Exp) = N_Type_Conversion
11714 and then Nkind (Expression (Exp)) = N_Function_Call
11717 ("illegal context for call"
11718 & " to function with limited result", Exp);
11722 ("initialization of limited object requires aggregate "
11723 & "or function call", Exp);
11729 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11730 -- set unless we can be sure that no range check is required.
11732 if (GNATprove_Mode or not Expander_Active)
11733 and then Is_Scalar_Type (T)
11734 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11736 Set_Do_Range_Check (Exp);
11738 end Check_Initialization;
11740 ----------------------
11741 -- Check_Interfaces --
11742 ----------------------
11744 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11745 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11748 Iface_Def : Node_Id;
11749 Iface_Typ : Entity_Id;
11750 Parent_Node : Node_Id;
11752 Is_Task : Boolean := False;
11753 -- Set True if parent type or any progenitor is a task interface
11755 Is_Protected : Boolean := False;
11756 -- Set True if parent type or any progenitor is a protected interface
11758 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11759 -- Check that a progenitor is compatible with declaration. If an error
11760 -- message is output, it is posted on Error_Node.
11766 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11767 Iface_Id : constant Entity_Id :=
11768 Defining_Identifier (Parent (Iface_Def));
11769 Type_Def : Node_Id;
11772 if Nkind (N) = N_Private_Extension_Declaration then
11775 Type_Def := Type_Definition (N);
11778 if Is_Task_Interface (Iface_Id) then
11781 elsif Is_Protected_Interface (Iface_Id) then
11782 Is_Protected := True;
11785 if Is_Synchronized_Interface (Iface_Id) then
11787 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11788 -- extension derived from a synchronized interface must explicitly
11789 -- be declared synchronized, because the full view will be a
11790 -- synchronized type.
11792 if Nkind (N) = N_Private_Extension_Declaration then
11793 if not Synchronized_Present (N) then
11795 ("private extension of& must be explicitly synchronized",
11799 -- However, by 3.9.4(16/2), a full type that is a record extension
11800 -- is never allowed to derive from a synchronized interface (note
11801 -- that interfaces must be excluded from this check, because those
11802 -- are represented by derived type definitions in some cases).
11804 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11805 and then not Interface_Present (Type_Definition (N))
11807 Error_Msg_N ("record extension cannot derive from synchronized "
11808 & "interface", Error_Node);
11812 -- Check that the characteristics of the progenitor are compatible
11813 -- with the explicit qualifier in the declaration.
11814 -- The check only applies to qualifiers that come from source.
11815 -- Limited_Present also appears in the declaration of corresponding
11816 -- records, and the check does not apply to them.
11818 if Limited_Present (Type_Def)
11820 Is_Concurrent_Record_Type (Defining_Identifier (N))
11822 if Is_Limited_Interface (Parent_Type)
11823 and then not Is_Limited_Interface (Iface_Id)
11826 ("progenitor & must be limited interface",
11827 Error_Node, Iface_Id);
11830 (Task_Present (Iface_Def)
11831 or else Protected_Present (Iface_Def)
11832 or else Synchronized_Present (Iface_Def))
11833 and then Nkind (N) /= N_Private_Extension_Declaration
11834 and then not Error_Posted (N)
11837 ("progenitor & must be limited interface",
11838 Error_Node, Iface_Id);
11841 -- Protected interfaces can only inherit from limited, synchronized
11842 -- or protected interfaces.
11844 elsif Nkind (N) = N_Full_Type_Declaration
11845 and then Protected_Present (Type_Def)
11847 if Limited_Present (Iface_Def)
11848 or else Synchronized_Present (Iface_Def)
11849 or else Protected_Present (Iface_Def)
11853 elsif Task_Present (Iface_Def) then
11854 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11855 & "from task interface", Error_Node);
11858 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11859 & "from non-limited interface", Error_Node);
11862 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11863 -- limited and synchronized.
11865 elsif Synchronized_Present (Type_Def) then
11866 if Limited_Present (Iface_Def)
11867 or else Synchronized_Present (Iface_Def)
11871 elsif Protected_Present (Iface_Def)
11872 and then Nkind (N) /= N_Private_Extension_Declaration
11874 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11875 & "from protected interface", Error_Node);
11877 elsif Task_Present (Iface_Def)
11878 and then Nkind (N) /= N_Private_Extension_Declaration
11880 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11881 & "from task interface", Error_Node);
11883 elsif not Is_Limited_Interface (Iface_Id) then
11884 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11885 & "from non-limited interface", Error_Node);
11888 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11889 -- synchronized or task interfaces.
11891 elsif Nkind (N) = N_Full_Type_Declaration
11892 and then Task_Present (Type_Def)
11894 if Limited_Present (Iface_Def)
11895 or else Synchronized_Present (Iface_Def)
11896 or else Task_Present (Iface_Def)
11900 elsif Protected_Present (Iface_Def) then
11901 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11902 & "protected interface", Error_Node);
11905 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11906 & "non-limited interface", Error_Node);
11911 -- Start of processing for Check_Interfaces
11914 if Is_Interface (Parent_Type) then
11915 if Is_Task_Interface (Parent_Type) then
11918 elsif Is_Protected_Interface (Parent_Type) then
11919 Is_Protected := True;
11923 if Nkind (N) = N_Private_Extension_Declaration then
11925 -- Check that progenitors are compatible with declaration
11927 Iface := First (Interface_List (Def));
11928 while Present (Iface) loop
11929 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11931 Parent_Node := Parent (Base_Type (Iface_Typ));
11932 Iface_Def := Type_Definition (Parent_Node);
11934 if not Is_Interface (Iface_Typ) then
11935 Diagnose_Interface (Iface, Iface_Typ);
11937 Check_Ifaces (Iface_Def, Iface);
11943 if Is_Task and Is_Protected then
11945 ("type cannot derive from task and protected interface", N);
11951 -- Full type declaration of derived type.
11952 -- Check compatibility with parent if it is interface type
11954 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11955 and then Is_Interface (Parent_Type)
11957 Parent_Node := Parent (Parent_Type);
11959 -- More detailed checks for interface varieties
11962 (Iface_Def => Type_Definition (Parent_Node),
11963 Error_Node => Subtype_Indication (Type_Definition (N)));
11966 Iface := First (Interface_List (Def));
11967 while Present (Iface) loop
11968 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11970 Parent_Node := Parent (Base_Type (Iface_Typ));
11971 Iface_Def := Type_Definition (Parent_Node);
11973 if not Is_Interface (Iface_Typ) then
11974 Diagnose_Interface (Iface, Iface_Typ);
11977 -- "The declaration of a specific descendant of an interface
11978 -- type freezes the interface type" RM 13.14
11980 Freeze_Before (N, Iface_Typ);
11981 Check_Ifaces (Iface_Def, Error_Node => Iface);
11987 if Is_Task and Is_Protected then
11989 ("type cannot derive from task and protected interface", N);
11991 end Check_Interfaces;
11993 ------------------------------------
11994 -- Check_Or_Process_Discriminants --
11995 ------------------------------------
11997 -- If an incomplete or private type declaration was already given for the
11998 -- type, the discriminants may have already been processed if they were
11999 -- present on the incomplete declaration. In this case a full conformance
12000 -- check has been performed in Find_Type_Name, and we then recheck here
12001 -- some properties that can't be checked on the partial view alone.
12002 -- Otherwise we call Process_Discriminants.
12004 procedure Check_Or_Process_Discriminants
12007 Prev : Entity_Id := Empty)
12010 if Has_Discriminants (T) then
12012 -- Discriminants are already set on T if they were already present
12013 -- on the partial view. Make them visible to component declarations.
12017 -- Discriminant on T (full view) referencing expr on partial view
12019 Prev_D : Entity_Id;
12020 -- Entity of corresponding discriminant on partial view
12023 -- Discriminant specification for full view, expression is
12024 -- the syntactic copy on full view (which has been checked for
12025 -- conformance with partial view), only used here to post error
12029 D := First_Discriminant (T);
12030 New_D := First (Discriminant_Specifications (N));
12031 while Present (D) loop
12032 Prev_D := Current_Entity (D);
12033 Set_Current_Entity (D);
12034 Set_Is_Immediately_Visible (D);
12035 Set_Homonym (D, Prev_D);
12037 -- Handle the case where there is an untagged partial view and
12038 -- the full view is tagged: must disallow discriminants with
12039 -- defaults, unless compiling for Ada 2012, which allows a
12040 -- limited tagged type to have defaulted discriminants (see
12041 -- AI05-0214). However, suppress error here if it was already
12042 -- reported on the default expression of the partial view.
12044 if Is_Tagged_Type (T)
12045 and then Present (Expression (Parent (D)))
12046 and then (not Is_Limited_Type (Current_Scope)
12047 or else Ada_Version < Ada_2012)
12048 and then not Error_Posted (Expression (Parent (D)))
12050 if Ada_Version >= Ada_2012 then
12052 ("discriminants of nonlimited tagged type cannot have "
12054 Expression (New_D));
12057 ("discriminants of tagged type cannot have defaults",
12058 Expression (New_D));
12062 -- Ada 2005 (AI-230): Access discriminant allowed in
12063 -- non-limited record types.
12065 if Ada_Version < Ada_2005 then
12067 -- This restriction gets applied to the full type here. It
12068 -- has already been applied earlier to the partial view.
12070 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
12073 Next_Discriminant (D);
12078 elsif Present (Discriminant_Specifications (N)) then
12079 Process_Discriminants (N, Prev);
12081 end Check_Or_Process_Discriminants;
12083 ----------------------
12084 -- Check_Real_Bound --
12085 ----------------------
12087 procedure Check_Real_Bound (Bound : Node_Id) is
12089 if not Is_Real_Type (Etype (Bound)) then
12091 ("bound in real type definition must be of real type", Bound);
12093 elsif not Is_OK_Static_Expression (Bound) then
12094 Flag_Non_Static_Expr
12095 ("non-static expression used for real type bound!", Bound);
12102 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
12104 Resolve (Bound, Standard_Float);
12105 end Check_Real_Bound;
12107 ------------------------------
12108 -- Complete_Private_Subtype --
12109 ------------------------------
12111 procedure Complete_Private_Subtype
12114 Full_Base : Entity_Id;
12115 Related_Nod : Node_Id)
12117 Save_Next_Entity : Entity_Id;
12118 Save_Homonym : Entity_Id;
12121 -- Set semantic attributes for (implicit) private subtype completion.
12122 -- If the full type has no discriminants, then it is a copy of the
12123 -- full view of the base. Otherwise, it is a subtype of the base with
12124 -- a possible discriminant constraint. Save and restore the original
12125 -- Next_Entity field of full to ensure that the calls to Copy_Node do
12126 -- not corrupt the entity chain.
12128 -- Note that the type of the full view is the same entity as the type
12129 -- of the partial view. In this fashion, the subtype has access to the
12130 -- correct view of the parent.
12132 Save_Next_Entity := Next_Entity (Full);
12133 Save_Homonym := Homonym (Priv);
12135 case Ekind (Full_Base) is
12136 when Class_Wide_Kind
12143 Copy_Node (Priv, Full);
12145 Set_Has_Discriminants
12146 (Full, Has_Discriminants (Full_Base));
12147 Set_Has_Unknown_Discriminants
12148 (Full, Has_Unknown_Discriminants (Full_Base));
12149 Set_First_Entity (Full, First_Entity (Full_Base));
12150 Set_Last_Entity (Full, Last_Entity (Full_Base));
12152 -- If the underlying base type is constrained, we know that the
12153 -- full view of the subtype is constrained as well (the converse
12154 -- is not necessarily true).
12156 if Is_Constrained (Full_Base) then
12157 Set_Is_Constrained (Full);
12161 Copy_Node (Full_Base, Full);
12163 Set_Chars (Full, Chars (Priv));
12164 Conditional_Delay (Full, Priv);
12165 Set_Sloc (Full, Sloc (Priv));
12168 Set_Next_Entity (Full, Save_Next_Entity);
12169 Set_Homonym (Full, Save_Homonym);
12170 Set_Associated_Node_For_Itype (Full, Related_Nod);
12172 -- Set common attributes for all subtypes: kind, convention, etc.
12174 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
12175 Set_Convention (Full, Convention (Full_Base));
12177 -- The Etype of the full view is inconsistent. Gigi needs to see the
12178 -- structural full view, which is what the current scheme gives: the
12179 -- Etype of the full view is the etype of the full base. However, if the
12180 -- full base is a derived type, the full view then looks like a subtype
12181 -- of the parent, not a subtype of the full base. If instead we write:
12183 -- Set_Etype (Full, Full_Base);
12185 -- then we get inconsistencies in the front-end (confusion between
12186 -- views). Several outstanding bugs are related to this ???
12188 Set_Is_First_Subtype (Full, False);
12189 Set_Scope (Full, Scope (Priv));
12190 Set_Size_Info (Full, Full_Base);
12191 Set_RM_Size (Full, RM_Size (Full_Base));
12192 Set_Is_Itype (Full);
12194 -- A subtype of a private-type-without-discriminants, whose full-view
12195 -- has discriminants with default expressions, is not constrained.
12197 if not Has_Discriminants (Priv) then
12198 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
12200 if Has_Discriminants (Full_Base) then
12201 Set_Discriminant_Constraint
12202 (Full, Discriminant_Constraint (Full_Base));
12204 -- The partial view may have been indefinite, the full view
12207 Set_Has_Unknown_Discriminants
12208 (Full, Has_Unknown_Discriminants (Full_Base));
12212 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
12213 Set_Depends_On_Private (Full, Has_Private_Component (Full));
12215 -- Freeze the private subtype entity if its parent is delayed, and not
12216 -- already frozen. We skip this processing if the type is an anonymous
12217 -- subtype of a record component, or is the corresponding record of a
12218 -- protected type, since these are processed when the enclosing type
12219 -- is frozen. If the parent type is declared in a nested package then
12220 -- the freezing of the private and full views also happens later.
12222 if not Is_Type (Scope (Full)) then
12224 and then In_Same_Source_Unit (Full, Full_Base)
12225 and then Scope (Full_Base) /= Scope (Full)
12227 Set_Has_Delayed_Freeze (Full);
12228 Set_Has_Delayed_Freeze (Priv);
12231 Set_Has_Delayed_Freeze (Full,
12232 Has_Delayed_Freeze (Full_Base)
12233 and then not Is_Frozen (Full_Base));
12237 Set_Freeze_Node (Full, Empty);
12238 Set_Is_Frozen (Full, False);
12239 Set_Full_View (Priv, Full);
12241 if Has_Discriminants (Full) then
12242 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
12243 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
12245 if Has_Unknown_Discriminants (Full) then
12246 Set_Discriminant_Constraint (Full, No_Elist);
12250 if Ekind (Full_Base) = E_Record_Type
12251 and then Has_Discriminants (Full_Base)
12252 and then Has_Discriminants (Priv) -- might not, if errors
12253 and then not Has_Unknown_Discriminants (Priv)
12254 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
12256 Create_Constrained_Components
12257 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
12259 -- If the full base is itself derived from private, build a congruent
12260 -- subtype of its underlying type, for use by the back end. For a
12261 -- constrained record component, the declaration cannot be placed on
12262 -- the component list, but it must nevertheless be built an analyzed, to
12263 -- supply enough information for Gigi to compute the size of component.
12265 elsif Ekind (Full_Base) in Private_Kind
12266 and then Is_Derived_Type (Full_Base)
12267 and then Has_Discriminants (Full_Base)
12268 and then (Ekind (Current_Scope) /= E_Record_Subtype)
12270 if not Is_Itype (Priv)
12272 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
12274 Build_Underlying_Full_View
12275 (Parent (Priv), Full, Etype (Full_Base));
12277 elsif Nkind (Related_Nod) = N_Component_Declaration then
12278 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
12281 elsif Is_Record_Type (Full_Base) then
12283 -- Show Full is simply a renaming of Full_Base
12285 Set_Cloned_Subtype (Full, Full_Base);
12288 -- It is unsafe to share the bounds of a scalar type, because the Itype
12289 -- is elaborated on demand, and if a bound is non-static then different
12290 -- orders of elaboration in different units will lead to different
12291 -- external symbols.
12293 if Is_Scalar_Type (Full_Base) then
12294 Set_Scalar_Range (Full,
12295 Make_Range (Sloc (Related_Nod),
12297 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
12299 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
12301 -- This completion inherits the bounds of the full parent, but if
12302 -- the parent is an unconstrained floating point type, so is the
12305 if Is_Floating_Point_Type (Full_Base) then
12306 Set_Includes_Infinities
12307 (Scalar_Range (Full), Has_Infinities (Full_Base));
12311 -- ??? It seems that a lot of fields are missing that should be copied
12312 -- from Full_Base to Full. Here are some that are introduced in a
12313 -- non-disruptive way but a cleanup is necessary.
12315 if Is_Tagged_Type (Full_Base) then
12316 Set_Is_Tagged_Type (Full);
12317 Set_Direct_Primitive_Operations
12318 (Full, Direct_Primitive_Operations (Full_Base));
12319 Set_No_Tagged_Streams_Pragma
12320 (Full, No_Tagged_Streams_Pragma (Full_Base));
12322 -- Inherit class_wide type of full_base in case the partial view was
12323 -- not tagged. Otherwise it has already been created when the private
12324 -- subtype was analyzed.
12326 if No (Class_Wide_Type (Full)) then
12327 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
12330 -- If this is a subtype of a protected or task type, constrain its
12331 -- corresponding record, unless this is a subtype without constraints,
12332 -- i.e. a simple renaming as with an actual subtype in an instance.
12334 elsif Is_Concurrent_Type (Full_Base) then
12335 if Has_Discriminants (Full)
12336 and then Present (Corresponding_Record_Type (Full_Base))
12338 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
12340 Set_Corresponding_Record_Type (Full,
12341 Constrain_Corresponding_Record
12342 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
12345 Set_Corresponding_Record_Type (Full,
12346 Corresponding_Record_Type (Full_Base));
12350 -- Link rep item chain, and also setting of Has_Predicates from private
12351 -- subtype to full subtype, since we will need these on the full subtype
12352 -- to create the predicate function. Note that the full subtype may
12353 -- already have rep items, inherited from the full view of the base
12354 -- type, so we must be sure not to overwrite these entries.
12359 Next_Item : Node_Id;
12360 Priv_Item : Node_Id;
12363 Item := First_Rep_Item (Full);
12364 Priv_Item := First_Rep_Item (Priv);
12366 -- If no existing rep items on full type, we can just link directly
12367 -- to the list of items on the private type, if any exist.. Same if
12368 -- the rep items are only those inherited from the base
12371 or else Nkind (Item) /= N_Aspect_Specification
12372 or else Entity (Item) = Full_Base)
12373 and then Present (First_Rep_Item (Priv))
12375 Set_First_Rep_Item (Full, Priv_Item);
12377 -- Otherwise, search to the end of items currently linked to the full
12378 -- subtype and append the private items to the end. However, if Priv
12379 -- and Full already have the same list of rep items, then the append
12380 -- is not done, as that would create a circularity.
12382 -- The partial view may have a predicate and the rep item lists of
12383 -- both views agree when inherited from the same ancestor. In that
12384 -- case, simply propagate the list from one view to the other.
12385 -- A more complex analysis needed here ???
12387 elsif Present (Priv_Item)
12388 and then Item = Next_Rep_Item (Priv_Item)
12390 Set_First_Rep_Item (Full, Priv_Item);
12392 elsif Item /= Priv_Item then
12395 Next_Item := Next_Rep_Item (Item);
12396 exit when No (Next_Item);
12399 -- If the private view has aspect specifications, the full view
12400 -- inherits them. Since these aspects may already have been
12401 -- attached to the full view during derivation, do not append
12402 -- them if already present.
12404 if Item = First_Rep_Item (Priv) then
12410 -- And link the private type items at the end of the chain
12413 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
12418 -- Make sure Has_Predicates is set on full type if it is set on the
12419 -- private type. Note that it may already be set on the full type and
12420 -- if so, we don't want to unset it. Similarly, propagate information
12421 -- about delayed aspects, because the corresponding pragmas must be
12422 -- analyzed when one of the views is frozen. This last step is needed
12423 -- in particular when the full type is a scalar type for which an
12424 -- anonymous base type is constructed.
12426 -- The predicate functions are generated either at the freeze point
12427 -- of the type or at the end of the visible part, and we must avoid
12428 -- generating them twice.
12430 if Has_Predicates (Priv) then
12431 Set_Has_Predicates (Full);
12433 if Present (Predicate_Function (Priv))
12434 and then No (Predicate_Function (Full))
12436 Set_Predicate_Function (Full, Predicate_Function (Priv));
12440 if Has_Delayed_Aspects (Priv) then
12441 Set_Has_Delayed_Aspects (Full);
12443 end Complete_Private_Subtype;
12445 ----------------------------
12446 -- Constant_Redeclaration --
12447 ----------------------------
12449 procedure Constant_Redeclaration
12454 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
12455 Obj_Def : constant Node_Id := Object_Definition (N);
12458 procedure Check_Possible_Deferred_Completion
12459 (Prev_Id : Entity_Id;
12460 Prev_Obj_Def : Node_Id;
12461 Curr_Obj_Def : Node_Id);
12462 -- Determine whether the two object definitions describe the partial
12463 -- and the full view of a constrained deferred constant. Generate
12464 -- a subtype for the full view and verify that it statically matches
12465 -- the subtype of the partial view.
12467 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12468 -- If deferred constant is an access type initialized with an allocator,
12469 -- check whether there is an illegal recursion in the definition,
12470 -- through a default value of some record subcomponent. This is normally
12471 -- detected when generating init procs, but requires this additional
12472 -- mechanism when expansion is disabled.
12474 ----------------------------------------
12475 -- Check_Possible_Deferred_Completion --
12476 ----------------------------------------
12478 procedure Check_Possible_Deferred_Completion
12479 (Prev_Id : Entity_Id;
12480 Prev_Obj_Def : Node_Id;
12481 Curr_Obj_Def : Node_Id)
12484 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12485 and then Present (Constraint (Prev_Obj_Def))
12486 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12487 and then Present (Constraint (Curr_Obj_Def))
12490 Loc : constant Source_Ptr := Sloc (N);
12491 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12492 Decl : constant Node_Id :=
12493 Make_Subtype_Declaration (Loc,
12494 Defining_Identifier => Def_Id,
12495 Subtype_Indication =>
12496 Relocate_Node (Curr_Obj_Def));
12499 Insert_Before_And_Analyze (N, Decl);
12500 Set_Etype (Id, Def_Id);
12502 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12503 Error_Msg_Sloc := Sloc (Prev_Id);
12504 Error_Msg_N ("subtype does not statically match deferred "
12505 & "declaration #", N);
12509 end Check_Possible_Deferred_Completion;
12511 ---------------------------------
12512 -- Check_Recursive_Declaration --
12513 ---------------------------------
12515 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12519 if Is_Record_Type (Typ) then
12520 Comp := First_Component (Typ);
12521 while Present (Comp) loop
12522 if Comes_From_Source (Comp) then
12523 if Present (Expression (Parent (Comp)))
12524 and then Is_Entity_Name (Expression (Parent (Comp)))
12525 and then Entity (Expression (Parent (Comp))) = Prev
12527 Error_Msg_Sloc := Sloc (Parent (Comp));
12529 ("illegal circularity with declaration for & #",
12533 elsif Is_Record_Type (Etype (Comp)) then
12534 Check_Recursive_Declaration (Etype (Comp));
12538 Next_Component (Comp);
12541 end Check_Recursive_Declaration;
12543 -- Start of processing for Constant_Redeclaration
12546 if Nkind (Parent (Prev)) = N_Object_Declaration then
12547 if Nkind (Object_Definition
12548 (Parent (Prev))) = N_Subtype_Indication
12550 -- Find type of new declaration. The constraints of the two
12551 -- views must match statically, but there is no point in
12552 -- creating an itype for the full view.
12554 if Nkind (Obj_Def) = N_Subtype_Indication then
12555 Find_Type (Subtype_Mark (Obj_Def));
12556 New_T := Entity (Subtype_Mark (Obj_Def));
12559 Find_Type (Obj_Def);
12560 New_T := Entity (Obj_Def);
12566 -- The full view may impose a constraint, even if the partial
12567 -- view does not, so construct the subtype.
12569 New_T := Find_Type_Of_Object (Obj_Def, N);
12574 -- Current declaration is illegal, diagnosed below in Enter_Name
12580 -- If previous full declaration or a renaming declaration exists, or if
12581 -- a homograph is present, let Enter_Name handle it, either with an
12582 -- error or with the removal of an overridden implicit subprogram.
12583 -- The previous one is a full declaration if it has an expression
12584 -- (which in the case of an aggregate is indicated by the Init flag).
12586 if Ekind (Prev) /= E_Constant
12587 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12588 or else Present (Expression (Parent (Prev)))
12589 or else Has_Init_Expression (Parent (Prev))
12590 or else Present (Full_View (Prev))
12594 -- Verify that types of both declarations match, or else that both types
12595 -- are anonymous access types whose designated subtypes statically match
12596 -- (as allowed in Ada 2005 by AI-385).
12598 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12600 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12601 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12602 or else Is_Access_Constant (Etype (New_T)) /=
12603 Is_Access_Constant (Etype (Prev))
12604 or else Can_Never_Be_Null (Etype (New_T)) /=
12605 Can_Never_Be_Null (Etype (Prev))
12606 or else Null_Exclusion_Present (Parent (Prev)) /=
12607 Null_Exclusion_Present (Parent (Id))
12608 or else not Subtypes_Statically_Match
12609 (Designated_Type (Etype (Prev)),
12610 Designated_Type (Etype (New_T))))
12612 Error_Msg_Sloc := Sloc (Prev);
12613 Error_Msg_N ("type does not match declaration#", N);
12614 Set_Full_View (Prev, Id);
12615 Set_Etype (Id, Any_Type);
12617 -- A deferred constant whose type is an anonymous array is always
12618 -- illegal (unless imported). A detailed error message might be
12619 -- helpful for Ada beginners.
12621 if Nkind (Object_Definition (Parent (Prev)))
12622 = N_Constrained_Array_Definition
12623 and then Nkind (Object_Definition (N))
12624 = N_Constrained_Array_Definition
12626 Error_Msg_N ("\each anonymous array is a distinct type", N);
12627 Error_Msg_N ("a deferred constant must have a named type",
12628 Object_Definition (Parent (Prev)));
12632 Null_Exclusion_Present (Parent (Prev))
12633 and then not Null_Exclusion_Present (N)
12635 Error_Msg_Sloc := Sloc (Prev);
12636 Error_Msg_N ("null-exclusion does not match declaration#", N);
12637 Set_Full_View (Prev, Id);
12638 Set_Etype (Id, Any_Type);
12640 -- If so, process the full constant declaration
12643 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12644 -- the deferred declaration is constrained, then the subtype defined
12645 -- by the subtype_indication in the full declaration shall match it
12648 Check_Possible_Deferred_Completion
12650 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12651 Curr_Obj_Def => Obj_Def);
12653 Set_Full_View (Prev, Id);
12654 Set_Is_Public (Id, Is_Public (Prev));
12655 Set_Is_Internal (Id);
12656 Append_Entity (Id, Current_Scope);
12658 -- Check ALIASED present if present before (RM 7.4(7))
12660 if Is_Aliased (Prev)
12661 and then not Aliased_Present (N)
12663 Error_Msg_Sloc := Sloc (Prev);
12664 Error_Msg_N ("ALIASED required (see declaration #)", N);
12667 -- Check that placement is in private part and that the incomplete
12668 -- declaration appeared in the visible part.
12670 if Ekind (Current_Scope) = E_Package
12671 and then not In_Private_Part (Current_Scope)
12673 Error_Msg_Sloc := Sloc (Prev);
12675 ("full constant for declaration # must be in private part", N);
12677 elsif Ekind (Current_Scope) = E_Package
12679 List_Containing (Parent (Prev)) /=
12680 Visible_Declarations (Package_Specification (Current_Scope))
12683 ("deferred constant must be declared in visible part",
12687 if Is_Access_Type (T)
12688 and then Nkind (Expression (N)) = N_Allocator
12690 Check_Recursive_Declaration (Designated_Type (T));
12693 -- A deferred constant is a visible entity. If type has invariants,
12694 -- verify that the initial value satisfies them.
12696 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12698 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12701 end Constant_Redeclaration;
12703 ----------------------
12704 -- Constrain_Access --
12705 ----------------------
12707 procedure Constrain_Access
12708 (Def_Id : in out Entity_Id;
12710 Related_Nod : Node_Id)
12712 T : constant Entity_Id := Entity (Subtype_Mark (S));
12713 Desig_Type : constant Entity_Id := Designated_Type (T);
12714 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12715 Constraint_OK : Boolean := True;
12718 if Is_Array_Type (Desig_Type) then
12719 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12721 elsif (Is_Record_Type (Desig_Type)
12722 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12723 and then not Is_Constrained (Desig_Type)
12725 -- ??? The following code is a temporary bypass to ignore a
12726 -- discriminant constraint on access type if it is constraining
12727 -- the current record. Avoid creating the implicit subtype of the
12728 -- record we are currently compiling since right now, we cannot
12729 -- handle these. For now, just return the access type itself.
12731 if Desig_Type = Current_Scope
12732 and then No (Def_Id)
12734 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12735 Def_Id := Entity (Subtype_Mark (S));
12737 -- This call added to ensure that the constraint is analyzed
12738 -- (needed for a B test). Note that we still return early from
12739 -- this procedure to avoid recursive processing. ???
12741 Constrain_Discriminated_Type
12742 (Desig_Subtype, S, Related_Nod, For_Access => True);
12746 -- Enforce rule that the constraint is illegal if there is an
12747 -- unconstrained view of the designated type. This means that the
12748 -- partial view (either a private type declaration or a derivation
12749 -- from a private type) has no discriminants. (Defect Report
12750 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12752 -- Rule updated for Ada 2005: The private type is said to have
12753 -- a constrained partial view, given that objects of the type
12754 -- can be declared. Furthermore, the rule applies to all access
12755 -- types, unlike the rule concerning default discriminants (see
12758 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12759 and then Has_Private_Declaration (Desig_Type)
12760 and then In_Open_Scopes (Scope (Desig_Type))
12761 and then Has_Discriminants (Desig_Type)
12764 Pack : constant Node_Id :=
12765 Unit_Declaration_Node (Scope (Desig_Type));
12770 if Nkind (Pack) = N_Package_Declaration then
12771 Decls := Visible_Declarations (Specification (Pack));
12772 Decl := First (Decls);
12773 while Present (Decl) loop
12774 if (Nkind (Decl) = N_Private_Type_Declaration
12775 and then Chars (Defining_Identifier (Decl)) =
12776 Chars (Desig_Type))
12779 (Nkind (Decl) = N_Full_Type_Declaration
12781 Chars (Defining_Identifier (Decl)) =
12783 and then Is_Derived_Type (Desig_Type)
12785 Has_Private_Declaration (Etype (Desig_Type)))
12787 if No (Discriminant_Specifications (Decl)) then
12789 ("cannot constrain access type if designated "
12790 & "type has constrained partial view", S);
12802 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12803 For_Access => True);
12805 elsif Is_Concurrent_Type (Desig_Type)
12806 and then not Is_Constrained (Desig_Type)
12808 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12811 Error_Msg_N ("invalid constraint on access type", S);
12813 -- We simply ignore an invalid constraint
12815 Desig_Subtype := Desig_Type;
12816 Constraint_OK := False;
12819 if No (Def_Id) then
12820 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12822 Set_Ekind (Def_Id, E_Access_Subtype);
12825 if Constraint_OK then
12826 Set_Etype (Def_Id, Base_Type (T));
12828 if Is_Private_Type (Desig_Type) then
12829 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12832 Set_Etype (Def_Id, Any_Type);
12835 Set_Size_Info (Def_Id, T);
12836 Set_Is_Constrained (Def_Id, Constraint_OK);
12837 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12838 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12839 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12841 Conditional_Delay (Def_Id, T);
12843 -- AI-363 : Subtypes of general access types whose designated types have
12844 -- default discriminants are disallowed. In instances, the rule has to
12845 -- be checked against the actual, of which T is the subtype. In a
12846 -- generic body, the rule is checked assuming that the actual type has
12847 -- defaulted discriminants.
12849 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12850 if Ekind (Base_Type (T)) = E_General_Access_Type
12851 and then Has_Defaulted_Discriminants (Desig_Type)
12853 if Ada_Version < Ada_2005 then
12855 ("access subtype of general access type would not " &
12856 "be allowed in Ada 2005?y?", S);
12859 ("access subtype of general access type not allowed", S);
12862 Error_Msg_N ("\discriminants have defaults", S);
12864 elsif Is_Access_Type (T)
12865 and then Is_Generic_Type (Desig_Type)
12866 and then Has_Discriminants (Desig_Type)
12867 and then In_Package_Body (Current_Scope)
12869 if Ada_Version < Ada_2005 then
12871 ("access subtype would not be allowed in generic body "
12872 & "in Ada 2005?y?", S);
12875 ("access subtype not allowed in generic body", S);
12879 ("\designated type is a discriminated formal", S);
12882 end Constrain_Access;
12884 ---------------------
12885 -- Constrain_Array --
12886 ---------------------
12888 procedure Constrain_Array
12889 (Def_Id : in out Entity_Id;
12891 Related_Nod : Node_Id;
12892 Related_Id : Entity_Id;
12893 Suffix : Character)
12895 C : constant Node_Id := Constraint (SI);
12896 Number_Of_Constraints : Nat := 0;
12899 Constraint_OK : Boolean := True;
12902 T := Entity (Subtype_Mark (SI));
12904 if Is_Access_Type (T) then
12905 T := Designated_Type (T);
12908 -- If an index constraint follows a subtype mark in a subtype indication
12909 -- then the type or subtype denoted by the subtype mark must not already
12910 -- impose an index constraint. The subtype mark must denote either an
12911 -- unconstrained array type or an access type whose designated type
12912 -- is such an array type... (RM 3.6.1)
12914 if Is_Constrained (T) then
12915 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12916 Constraint_OK := False;
12919 S := First (Constraints (C));
12920 while Present (S) loop
12921 Number_Of_Constraints := Number_Of_Constraints + 1;
12925 -- In either case, the index constraint must provide a discrete
12926 -- range for each index of the array type and the type of each
12927 -- discrete range must be the same as that of the corresponding
12928 -- index. (RM 3.6.1)
12930 if Number_Of_Constraints /= Number_Dimensions (T) then
12931 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12932 Constraint_OK := False;
12935 S := First (Constraints (C));
12936 Index := First_Index (T);
12939 -- Apply constraints to each index type
12941 for J in 1 .. Number_Of_Constraints loop
12942 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12950 if No (Def_Id) then
12952 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12953 Set_Parent (Def_Id, Related_Nod);
12956 Set_Ekind (Def_Id, E_Array_Subtype);
12959 Set_Size_Info (Def_Id, (T));
12960 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12961 Set_Etype (Def_Id, Base_Type (T));
12963 if Constraint_OK then
12964 Set_First_Index (Def_Id, First (Constraints (C)));
12966 Set_First_Index (Def_Id, First_Index (T));
12969 Set_Is_Constrained (Def_Id, True);
12970 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12971 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12973 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12974 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12976 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12977 -- We need to initialize the attribute because if Def_Id is previously
12978 -- analyzed through a limited_with clause, it will have the attributes
12979 -- of an incomplete type, one of which is an Elist that overlaps the
12980 -- Packed_Array_Impl_Type field.
12982 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12984 -- Build a freeze node if parent still needs one. Also make sure that
12985 -- the Depends_On_Private status is set because the subtype will need
12986 -- reprocessing at the time the base type does, and also we must set a
12987 -- conditional delay.
12989 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12990 Conditional_Delay (Def_Id, T);
12991 end Constrain_Array;
12993 ------------------------------
12994 -- Constrain_Component_Type --
12995 ------------------------------
12997 function Constrain_Component_Type
12999 Constrained_Typ : Entity_Id;
13000 Related_Node : Node_Id;
13002 Constraints : Elist_Id) return Entity_Id
13004 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
13005 Compon_Type : constant Entity_Id := Etype (Comp);
13007 function Build_Constrained_Array_Type
13008 (Old_Type : Entity_Id) return Entity_Id;
13009 -- If Old_Type is an array type, one of whose indexes is constrained
13010 -- by a discriminant, build an Itype whose constraint replaces the
13011 -- discriminant with its value in the constraint.
13013 function Build_Constrained_Discriminated_Type
13014 (Old_Type : Entity_Id) return Entity_Id;
13015 -- Ditto for record components
13017 function Build_Constrained_Access_Type
13018 (Old_Type : Entity_Id) return Entity_Id;
13019 -- Ditto for access types. Makes use of previous two functions, to
13020 -- constrain designated type.
13022 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
13023 -- T is an array or discriminated type, C is a list of constraints
13024 -- that apply to T. This routine builds the constrained subtype.
13026 function Is_Discriminant (Expr : Node_Id) return Boolean;
13027 -- Returns True if Expr is a discriminant
13029 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
13030 -- Find the value of discriminant Discrim in Constraint
13032 -----------------------------------
13033 -- Build_Constrained_Access_Type --
13034 -----------------------------------
13036 function Build_Constrained_Access_Type
13037 (Old_Type : Entity_Id) return Entity_Id
13039 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
13041 Desig_Subtype : Entity_Id;
13045 -- if the original access type was not embedded in the enclosing
13046 -- type definition, there is no need to produce a new access
13047 -- subtype. In fact every access type with an explicit constraint
13048 -- generates an itype whose scope is the enclosing record.
13050 if not Is_Type (Scope (Old_Type)) then
13053 elsif Is_Array_Type (Desig_Type) then
13054 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
13056 elsif Has_Discriminants (Desig_Type) then
13058 -- This may be an access type to an enclosing record type for
13059 -- which we are constructing the constrained components. Return
13060 -- the enclosing record subtype. This is not always correct,
13061 -- but avoids infinite recursion. ???
13063 Desig_Subtype := Any_Type;
13065 for J in reverse 0 .. Scope_Stack.Last loop
13066 Scop := Scope_Stack.Table (J).Entity;
13069 and then Base_Type (Scop) = Base_Type (Desig_Type)
13071 Desig_Subtype := Scop;
13074 exit when not Is_Type (Scop);
13077 if Desig_Subtype = Any_Type then
13079 Build_Constrained_Discriminated_Type (Desig_Type);
13086 if Desig_Subtype /= Desig_Type then
13088 -- The Related_Node better be here or else we won't be able
13089 -- to attach new itypes to a node in the tree.
13091 pragma Assert (Present (Related_Node));
13093 Itype := Create_Itype (E_Access_Subtype, Related_Node);
13095 Set_Etype (Itype, Base_Type (Old_Type));
13096 Set_Size_Info (Itype, (Old_Type));
13097 Set_Directly_Designated_Type (Itype, Desig_Subtype);
13098 Set_Depends_On_Private (Itype, Has_Private_Component
13100 Set_Is_Access_Constant (Itype, Is_Access_Constant
13103 -- The new itype needs freezing when it depends on a not frozen
13104 -- type and the enclosing subtype needs freezing.
13106 if Has_Delayed_Freeze (Constrained_Typ)
13107 and then not Is_Frozen (Constrained_Typ)
13109 Conditional_Delay (Itype, Base_Type (Old_Type));
13117 end Build_Constrained_Access_Type;
13119 ----------------------------------
13120 -- Build_Constrained_Array_Type --
13121 ----------------------------------
13123 function Build_Constrained_Array_Type
13124 (Old_Type : Entity_Id) return Entity_Id
13128 Old_Index : Node_Id;
13129 Range_Node : Node_Id;
13130 Constr_List : List_Id;
13132 Need_To_Create_Itype : Boolean := False;
13135 Old_Index := First_Index (Old_Type);
13136 while Present (Old_Index) loop
13137 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
13139 if Is_Discriminant (Lo_Expr)
13141 Is_Discriminant (Hi_Expr)
13143 Need_To_Create_Itype := True;
13146 Next_Index (Old_Index);
13149 if Need_To_Create_Itype then
13150 Constr_List := New_List;
13152 Old_Index := First_Index (Old_Type);
13153 while Present (Old_Index) loop
13154 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
13156 if Is_Discriminant (Lo_Expr) then
13157 Lo_Expr := Get_Discr_Value (Lo_Expr);
13160 if Is_Discriminant (Hi_Expr) then
13161 Hi_Expr := Get_Discr_Value (Hi_Expr);
13166 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
13168 Append (Range_Node, To => Constr_List);
13170 Next_Index (Old_Index);
13173 return Build_Subtype (Old_Type, Constr_List);
13178 end Build_Constrained_Array_Type;
13180 ------------------------------------------
13181 -- Build_Constrained_Discriminated_Type --
13182 ------------------------------------------
13184 function Build_Constrained_Discriminated_Type
13185 (Old_Type : Entity_Id) return Entity_Id
13188 Constr_List : List_Id;
13189 Old_Constraint : Elmt_Id;
13191 Need_To_Create_Itype : Boolean := False;
13194 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13195 while Present (Old_Constraint) loop
13196 Expr := Node (Old_Constraint);
13198 if Is_Discriminant (Expr) then
13199 Need_To_Create_Itype := True;
13202 Next_Elmt (Old_Constraint);
13205 if Need_To_Create_Itype then
13206 Constr_List := New_List;
13208 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13209 while Present (Old_Constraint) loop
13210 Expr := Node (Old_Constraint);
13212 if Is_Discriminant (Expr) then
13213 Expr := Get_Discr_Value (Expr);
13216 Append (New_Copy_Tree (Expr), To => Constr_List);
13218 Next_Elmt (Old_Constraint);
13221 return Build_Subtype (Old_Type, Constr_List);
13226 end Build_Constrained_Discriminated_Type;
13228 -------------------
13229 -- Build_Subtype --
13230 -------------------
13232 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
13234 Subtyp_Decl : Node_Id;
13235 Def_Id : Entity_Id;
13236 Btyp : Entity_Id := Base_Type (T);
13239 -- The Related_Node better be here or else we won't be able to
13240 -- attach new itypes to a node in the tree.
13242 pragma Assert (Present (Related_Node));
13244 -- If the view of the component's type is incomplete or private
13245 -- with unknown discriminants, then the constraint must be applied
13246 -- to the full type.
13248 if Has_Unknown_Discriminants (Btyp)
13249 and then Present (Underlying_Type (Btyp))
13251 Btyp := Underlying_Type (Btyp);
13255 Make_Subtype_Indication (Loc,
13256 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
13257 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
13259 Def_Id := Create_Itype (Ekind (T), Related_Node);
13262 Make_Subtype_Declaration (Loc,
13263 Defining_Identifier => Def_Id,
13264 Subtype_Indication => Indic);
13266 Set_Parent (Subtyp_Decl, Parent (Related_Node));
13268 -- Itypes must be analyzed with checks off (see package Itypes)
13270 Analyze (Subtyp_Decl, Suppress => All_Checks);
13275 ---------------------
13276 -- Get_Discr_Value --
13277 ---------------------
13279 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
13284 -- The discriminant may be declared for the type, in which case we
13285 -- find it by iterating over the list of discriminants. If the
13286 -- discriminant is inherited from a parent type, it appears as the
13287 -- corresponding discriminant of the current type. This will be the
13288 -- case when constraining an inherited component whose constraint is
13289 -- given by a discriminant of the parent.
13291 D := First_Discriminant (Typ);
13292 E := First_Elmt (Constraints);
13294 while Present (D) loop
13295 if D = Entity (Discrim)
13296 or else D = CR_Discriminant (Entity (Discrim))
13297 or else Corresponding_Discriminant (D) = Entity (Discrim)
13302 Next_Discriminant (D);
13306 -- The Corresponding_Discriminant mechanism is incomplete, because
13307 -- the correspondence between new and old discriminants is not one
13308 -- to one: one new discriminant can constrain several old ones. In
13309 -- that case, scan sequentially the stored_constraint, the list of
13310 -- discriminants of the parents, and the constraints.
13312 -- Previous code checked for the present of the Stored_Constraint
13313 -- list for the derived type, but did not use it at all. Should it
13314 -- be present when the component is a discriminated task type?
13316 if Is_Derived_Type (Typ)
13317 and then Scope (Entity (Discrim)) = Etype (Typ)
13319 D := First_Discriminant (Etype (Typ));
13320 E := First_Elmt (Constraints);
13321 while Present (D) loop
13322 if D = Entity (Discrim) then
13326 Next_Discriminant (D);
13331 -- Something is wrong if we did not find the value
13333 raise Program_Error;
13334 end Get_Discr_Value;
13336 ---------------------
13337 -- Is_Discriminant --
13338 ---------------------
13340 function Is_Discriminant (Expr : Node_Id) return Boolean is
13341 Discrim_Scope : Entity_Id;
13344 if Denotes_Discriminant (Expr) then
13345 Discrim_Scope := Scope (Entity (Expr));
13347 -- Either we have a reference to one of Typ's discriminants,
13349 pragma Assert (Discrim_Scope = Typ
13351 -- or to the discriminants of the parent type, in the case
13352 -- of a derivation of a tagged type with variants.
13354 or else Discrim_Scope = Etype (Typ)
13355 or else Full_View (Discrim_Scope) = Etype (Typ)
13357 -- or same as above for the case where the discriminants
13358 -- were declared in Typ's private view.
13360 or else (Is_Private_Type (Discrim_Scope)
13361 and then Chars (Discrim_Scope) = Chars (Typ))
13363 -- or else we are deriving from the full view and the
13364 -- discriminant is declared in the private entity.
13366 or else (Is_Private_Type (Typ)
13367 and then Chars (Discrim_Scope) = Chars (Typ))
13369 -- Or we are constrained the corresponding record of a
13370 -- synchronized type that completes a private declaration.
13372 or else (Is_Concurrent_Record_Type (Typ)
13374 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
13376 -- or we have a class-wide type, in which case make sure the
13377 -- discriminant found belongs to the root type.
13379 or else (Is_Class_Wide_Type (Typ)
13380 and then Etype (Typ) = Discrim_Scope));
13385 -- In all other cases we have something wrong
13388 end Is_Discriminant;
13390 -- Start of processing for Constrain_Component_Type
13393 if Nkind (Parent (Comp)) = N_Component_Declaration
13394 and then Comes_From_Source (Parent (Comp))
13395 and then Comes_From_Source
13396 (Subtype_Indication (Component_Definition (Parent (Comp))))
13399 (Subtype_Indication (Component_Definition (Parent (Comp))))
13401 return Compon_Type;
13403 elsif Is_Array_Type (Compon_Type) then
13404 return Build_Constrained_Array_Type (Compon_Type);
13406 elsif Has_Discriminants (Compon_Type) then
13407 return Build_Constrained_Discriminated_Type (Compon_Type);
13409 elsif Is_Access_Type (Compon_Type) then
13410 return Build_Constrained_Access_Type (Compon_Type);
13413 return Compon_Type;
13415 end Constrain_Component_Type;
13417 --------------------------
13418 -- Constrain_Concurrent --
13419 --------------------------
13421 -- For concurrent types, the associated record value type carries the same
13422 -- discriminants, so when we constrain a concurrent type, we must constrain
13423 -- the corresponding record type as well.
13425 procedure Constrain_Concurrent
13426 (Def_Id : in out Entity_Id;
13428 Related_Nod : Node_Id;
13429 Related_Id : Entity_Id;
13430 Suffix : Character)
13432 -- Retrieve Base_Type to ensure getting to the concurrent type in the
13433 -- case of a private subtype (needed when only doing semantic analysis).
13435 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
13439 if Is_Access_Type (T_Ent) then
13440 T_Ent := Designated_Type (T_Ent);
13443 T_Val := Corresponding_Record_Type (T_Ent);
13445 if Present (T_Val) then
13447 if No (Def_Id) then
13448 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13450 -- Elaborate itype now, as it may be used in a subsequent
13451 -- synchronized operation in another scope.
13453 if Nkind (Related_Nod) = N_Full_Type_Declaration then
13454 Build_Itype_Reference (Def_Id, Related_Nod);
13458 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13460 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13461 Set_Corresponding_Record_Type (Def_Id,
13462 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13465 -- If there is no associated record, expansion is disabled and this
13466 -- is a generic context. Create a subtype in any case, so that
13467 -- semantic analysis can proceed.
13469 if No (Def_Id) then
13470 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13473 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13475 end Constrain_Concurrent;
13477 ------------------------------------
13478 -- Constrain_Corresponding_Record --
13479 ------------------------------------
13481 function Constrain_Corresponding_Record
13482 (Prot_Subt : Entity_Id;
13483 Corr_Rec : Entity_Id;
13484 Related_Nod : Node_Id) return Entity_Id
13486 T_Sub : constant Entity_Id :=
13487 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13490 Set_Etype (T_Sub, Corr_Rec);
13491 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13492 Set_Is_Constrained (T_Sub, True);
13493 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13494 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13496 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13497 Set_Discriminant_Constraint
13498 (T_Sub, Discriminant_Constraint (Prot_Subt));
13499 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13500 Create_Constrained_Components
13501 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13504 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13506 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13507 Conditional_Delay (T_Sub, Corr_Rec);
13510 -- This is a component subtype: it will be frozen in the context of
13511 -- the enclosing record's init_proc, so that discriminant references
13512 -- are resolved to discriminals. (Note: we used to skip freezing
13513 -- altogether in that case, which caused errors downstream for
13514 -- components of a bit packed array type).
13516 Set_Has_Delayed_Freeze (T_Sub);
13520 end Constrain_Corresponding_Record;
13522 -----------------------
13523 -- Constrain_Decimal --
13524 -----------------------
13526 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13527 T : constant Entity_Id := Entity (Subtype_Mark (S));
13528 C : constant Node_Id := Constraint (S);
13529 Loc : constant Source_Ptr := Sloc (C);
13530 Range_Expr : Node_Id;
13531 Digits_Expr : Node_Id;
13536 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13538 if Nkind (C) = N_Range_Constraint then
13539 Range_Expr := Range_Expression (C);
13540 Digits_Val := Digits_Value (T);
13543 pragma Assert (Nkind (C) = N_Digits_Constraint);
13545 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13547 Digits_Expr := Digits_Expression (C);
13548 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13550 Check_Digits_Expression (Digits_Expr);
13551 Digits_Val := Expr_Value (Digits_Expr);
13553 if Digits_Val > Digits_Value (T) then
13555 ("digits expression is incompatible with subtype", C);
13556 Digits_Val := Digits_Value (T);
13559 if Present (Range_Constraint (C)) then
13560 Range_Expr := Range_Expression (Range_Constraint (C));
13562 Range_Expr := Empty;
13566 Set_Etype (Def_Id, Base_Type (T));
13567 Set_Size_Info (Def_Id, (T));
13568 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13569 Set_Delta_Value (Def_Id, Delta_Value (T));
13570 Set_Scale_Value (Def_Id, Scale_Value (T));
13571 Set_Small_Value (Def_Id, Small_Value (T));
13572 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13573 Set_Digits_Value (Def_Id, Digits_Val);
13575 -- Manufacture range from given digits value if no range present
13577 if No (Range_Expr) then
13578 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13582 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13584 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13587 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13588 Set_Discrete_RM_Size (Def_Id);
13590 -- Unconditionally delay the freeze, since we cannot set size
13591 -- information in all cases correctly until the freeze point.
13593 Set_Has_Delayed_Freeze (Def_Id);
13594 end Constrain_Decimal;
13596 ----------------------------------
13597 -- Constrain_Discriminated_Type --
13598 ----------------------------------
13600 procedure Constrain_Discriminated_Type
13601 (Def_Id : Entity_Id;
13603 Related_Nod : Node_Id;
13604 For_Access : Boolean := False)
13606 E : Entity_Id := Entity (Subtype_Mark (S));
13609 procedure Fixup_Bad_Constraint;
13610 -- Called after finding a bad constraint, and after having posted an
13611 -- appropriate error message. The goal is to leave type Def_Id in as
13612 -- reasonable state as possible.
13614 --------------------------
13615 -- Fixup_Bad_Constraint --
13616 --------------------------
13618 procedure Fixup_Bad_Constraint is
13620 -- Set a reasonable Ekind for the entity, including incomplete types.
13622 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13624 -- Set Etype to the known type, to reduce chances of cascaded errors
13626 Set_Etype (Def_Id, E);
13627 Set_Error_Posted (Def_Id);
13628 end Fixup_Bad_Constraint;
13633 Constr : Elist_Id := New_Elmt_List;
13635 -- Start of processing for Constrain_Discriminated_Type
13638 C := Constraint (S);
13640 -- A discriminant constraint is only allowed in a subtype indication,
13641 -- after a subtype mark. This subtype mark must denote either a type
13642 -- with discriminants, or an access type whose designated type is a
13643 -- type with discriminants. A discriminant constraint specifies the
13644 -- values of these discriminants (RM 3.7.2(5)).
13646 T := Base_Type (Entity (Subtype_Mark (S)));
13648 if Is_Access_Type (T) then
13649 T := Designated_Type (T);
13652 -- In an instance it may be necessary to retrieve the full view of a
13653 -- type with unknown discriminants, or a full view with defaulted
13654 -- discriminants. In other contexts the constraint is illegal.
13657 and then Is_Private_Type (T)
13658 and then Present (Full_View (T))
13660 (Has_Unknown_Discriminants (T)
13662 (not Has_Discriminants (T)
13663 and then Has_Discriminants (Full_View (T))
13664 and then Present (Discriminant_Default_Value
13665 (First_Discriminant (Full_View (T))))))
13667 T := Full_View (T);
13668 E := Full_View (E);
13671 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13672 -- generating an error for access-to-incomplete subtypes.
13674 if Ada_Version >= Ada_2005
13675 and then Ekind (T) = E_Incomplete_Type
13676 and then Nkind (Parent (S)) = N_Subtype_Declaration
13677 and then not Is_Itype (Def_Id)
13679 -- A little sanity check: emit an error message if the type has
13680 -- discriminants to begin with. Type T may be a regular incomplete
13681 -- type or imported via a limited with clause.
13683 if Has_Discriminants (T)
13684 or else (From_Limited_With (T)
13685 and then Present (Non_Limited_View (T))
13686 and then Nkind (Parent (Non_Limited_View (T))) =
13687 N_Full_Type_Declaration
13688 and then Present (Discriminant_Specifications
13689 (Parent (Non_Limited_View (T)))))
13692 ("(Ada 2005) incomplete subtype may not be constrained", C);
13694 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13697 Fixup_Bad_Constraint;
13700 -- Check that the type has visible discriminants. The type may be
13701 -- a private type with unknown discriminants whose full view has
13702 -- discriminants which are invisible.
13704 elsif not Has_Discriminants (T)
13706 (Has_Unknown_Discriminants (T)
13707 and then Is_Private_Type (T))
13709 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13710 Fixup_Bad_Constraint;
13713 elsif Is_Constrained (E)
13714 or else (Ekind (E) = E_Class_Wide_Subtype
13715 and then Present (Discriminant_Constraint (E)))
13717 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13718 Fixup_Bad_Constraint;
13722 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13723 -- applies to the base type.
13725 T := Base_Type (T);
13727 Constr := Build_Discriminant_Constraints (T, S);
13729 -- If the list returned was empty we had an error in building the
13730 -- discriminant constraint. We have also already signalled an error
13731 -- in the incomplete type case
13733 if Is_Empty_Elmt_List (Constr) then
13734 Fixup_Bad_Constraint;
13738 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13739 end Constrain_Discriminated_Type;
13741 ---------------------------
13742 -- Constrain_Enumeration --
13743 ---------------------------
13745 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13746 T : constant Entity_Id := Entity (Subtype_Mark (S));
13747 C : constant Node_Id := Constraint (S);
13750 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13752 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13754 Set_Etype (Def_Id, Base_Type (T));
13755 Set_Size_Info (Def_Id, (T));
13756 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13757 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13759 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13761 Set_Discrete_RM_Size (Def_Id);
13762 end Constrain_Enumeration;
13764 ----------------------
13765 -- Constrain_Float --
13766 ----------------------
13768 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13769 T : constant Entity_Id := Entity (Subtype_Mark (S));
13775 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13777 Set_Etype (Def_Id, Base_Type (T));
13778 Set_Size_Info (Def_Id, (T));
13779 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13781 -- Process the constraint
13783 C := Constraint (S);
13785 -- Digits constraint present
13787 if Nkind (C) = N_Digits_Constraint then
13789 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13790 Check_Restriction (No_Obsolescent_Features, C);
13792 if Warn_On_Obsolescent_Feature then
13794 ("subtype digits constraint is an " &
13795 "obsolescent feature (RM J.3(8))?j?", C);
13798 D := Digits_Expression (C);
13799 Analyze_And_Resolve (D, Any_Integer);
13800 Check_Digits_Expression (D);
13801 Set_Digits_Value (Def_Id, Expr_Value (D));
13803 -- Check that digits value is in range. Obviously we can do this
13804 -- at compile time, but it is strictly a runtime check, and of
13805 -- course there is an ACVC test that checks this.
13807 if Digits_Value (Def_Id) > Digits_Value (T) then
13808 Error_Msg_Uint_1 := Digits_Value (T);
13809 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13811 Make_Raise_Constraint_Error (Sloc (D),
13812 Reason => CE_Range_Check_Failed);
13813 Insert_Action (Declaration_Node (Def_Id), Rais);
13816 C := Range_Constraint (C);
13818 -- No digits constraint present
13821 Set_Digits_Value (Def_Id, Digits_Value (T));
13824 -- Range constraint present
13826 if Nkind (C) = N_Range_Constraint then
13827 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13829 -- No range constraint present
13832 pragma Assert (No (C));
13833 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13836 Set_Is_Constrained (Def_Id);
13837 end Constrain_Float;
13839 ---------------------
13840 -- Constrain_Index --
13841 ---------------------
13843 procedure Constrain_Index
13846 Related_Nod : Node_Id;
13847 Related_Id : Entity_Id;
13848 Suffix : Character;
13849 Suffix_Index : Nat)
13851 Def_Id : Entity_Id;
13852 R : Node_Id := Empty;
13853 T : constant Entity_Id := Etype (Index);
13857 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13858 Set_Etype (Def_Id, Base_Type (T));
13860 if Nkind (S) = N_Range
13862 (Nkind (S) = N_Attribute_Reference
13863 and then Attribute_Name (S) = Name_Range)
13865 -- A Range attribute will be transformed into N_Range by Resolve
13871 Process_Range_Expr_In_Decl (R, T);
13873 if not Error_Posted (S)
13875 (Nkind (S) /= N_Range
13876 or else not Covers (T, (Etype (Low_Bound (S))))
13877 or else not Covers (T, (Etype (High_Bound (S)))))
13879 if Base_Type (T) /= Any_Type
13880 and then Etype (Low_Bound (S)) /= Any_Type
13881 and then Etype (High_Bound (S)) /= Any_Type
13883 Error_Msg_N ("range expected", S);
13887 elsif Nkind (S) = N_Subtype_Indication then
13889 -- The parser has verified that this is a discrete indication
13891 Resolve_Discrete_Subtype_Indication (S, T);
13892 Bad_Predicated_Subtype_Use
13893 ("subtype& has predicate, not allowed in index constraint",
13894 S, Entity (Subtype_Mark (S)));
13896 R := Range_Expression (Constraint (S));
13898 -- Capture values of bounds and generate temporaries for them if
13899 -- needed, since checks may cause duplication of the expressions
13900 -- which must not be reevaluated.
13902 -- The forced evaluation removes side effects from expressions, which
13903 -- should occur also in GNATprove mode. Otherwise, we end up with
13904 -- unexpected insertions of actions at places where this is not
13905 -- supposed to occur, e.g. on default parameters of a call.
13907 if Expander_Active or GNATprove_Mode then
13909 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13911 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13914 elsif Nkind (S) = N_Discriminant_Association then
13916 -- Syntactically valid in subtype indication
13918 Error_Msg_N ("invalid index constraint", S);
13919 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13922 -- Subtype_Mark case, no anonymous subtypes to construct
13927 if Is_Entity_Name (S) then
13928 if not Is_Type (Entity (S)) then
13929 Error_Msg_N ("expect subtype mark for index constraint", S);
13931 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13932 Wrong_Type (S, Base_Type (T));
13934 -- Check error of subtype with predicate in index constraint
13937 Bad_Predicated_Subtype_Use
13938 ("subtype& has predicate, not allowed in index constraint",
13945 Error_Msg_N ("invalid index constraint", S);
13946 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13951 -- Complete construction of the Itype
13953 if Is_Modular_Integer_Type (T) then
13954 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13956 elsif Is_Integer_Type (T) then
13957 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13960 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13961 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13962 Set_First_Literal (Def_Id, First_Literal (T));
13965 Set_Size_Info (Def_Id, (T));
13966 Set_RM_Size (Def_Id, RM_Size (T));
13967 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13969 Set_Scalar_Range (Def_Id, R);
13971 Set_Etype (S, Def_Id);
13972 Set_Discrete_RM_Size (Def_Id);
13973 end Constrain_Index;
13975 -----------------------
13976 -- Constrain_Integer --
13977 -----------------------
13979 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13980 T : constant Entity_Id := Entity (Subtype_Mark (S));
13981 C : constant Node_Id := Constraint (S);
13984 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13986 if Is_Modular_Integer_Type (T) then
13987 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13989 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13992 Set_Etype (Def_Id, Base_Type (T));
13993 Set_Size_Info (Def_Id, (T));
13994 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13995 Set_Discrete_RM_Size (Def_Id);
13996 end Constrain_Integer;
13998 ------------------------------
13999 -- Constrain_Ordinary_Fixed --
14000 ------------------------------
14002 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
14003 T : constant Entity_Id := Entity (Subtype_Mark (S));
14009 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
14010 Set_Etype (Def_Id, Base_Type (T));
14011 Set_Size_Info (Def_Id, (T));
14012 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
14013 Set_Small_Value (Def_Id, Small_Value (T));
14015 -- Process the constraint
14017 C := Constraint (S);
14019 -- Delta constraint present
14021 if Nkind (C) = N_Delta_Constraint then
14023 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
14024 Check_Restriction (No_Obsolescent_Features, C);
14026 if Warn_On_Obsolescent_Feature then
14028 ("subtype delta constraint is an " &
14029 "obsolescent feature (RM J.3(7))?j?");
14032 D := Delta_Expression (C);
14033 Analyze_And_Resolve (D, Any_Real);
14034 Check_Delta_Expression (D);
14035 Set_Delta_Value (Def_Id, Expr_Value_R (D));
14037 -- Check that delta value is in range. Obviously we can do this
14038 -- at compile time, but it is strictly a runtime check, and of
14039 -- course there is an ACVC test that checks this.
14041 if Delta_Value (Def_Id) < Delta_Value (T) then
14042 Error_Msg_N ("??delta value is too small", D);
14044 Make_Raise_Constraint_Error (Sloc (D),
14045 Reason => CE_Range_Check_Failed);
14046 Insert_Action (Declaration_Node (Def_Id), Rais);
14049 C := Range_Constraint (C);
14051 -- No delta constraint present
14054 Set_Delta_Value (Def_Id, Delta_Value (T));
14057 -- Range constraint present
14059 if Nkind (C) = N_Range_Constraint then
14060 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
14062 -- No range constraint present
14065 pragma Assert (No (C));
14066 Set_Scalar_Range (Def_Id, Scalar_Range (T));
14069 Set_Discrete_RM_Size (Def_Id);
14071 -- Unconditionally delay the freeze, since we cannot set size
14072 -- information in all cases correctly until the freeze point.
14074 Set_Has_Delayed_Freeze (Def_Id);
14075 end Constrain_Ordinary_Fixed;
14077 -----------------------
14078 -- Contain_Interface --
14079 -----------------------
14081 function Contain_Interface
14082 (Iface : Entity_Id;
14083 Ifaces : Elist_Id) return Boolean
14085 Iface_Elmt : Elmt_Id;
14088 if Present (Ifaces) then
14089 Iface_Elmt := First_Elmt (Ifaces);
14090 while Present (Iface_Elmt) loop
14091 if Node (Iface_Elmt) = Iface then
14095 Next_Elmt (Iface_Elmt);
14100 end Contain_Interface;
14102 ---------------------------
14103 -- Convert_Scalar_Bounds --
14104 ---------------------------
14106 procedure Convert_Scalar_Bounds
14108 Parent_Type : Entity_Id;
14109 Derived_Type : Entity_Id;
14112 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
14119 -- Defend against previous errors
14121 if No (Scalar_Range (Derived_Type)) then
14122 Check_Error_Detected;
14126 Lo := Build_Scalar_Bound
14127 (Type_Low_Bound (Derived_Type),
14128 Parent_Type, Implicit_Base);
14130 Hi := Build_Scalar_Bound
14131 (Type_High_Bound (Derived_Type),
14132 Parent_Type, Implicit_Base);
14139 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
14141 Set_Parent (Rng, N);
14142 Set_Scalar_Range (Derived_Type, Rng);
14144 -- Analyze the bounds
14146 Analyze_And_Resolve (Lo, Implicit_Base);
14147 Analyze_And_Resolve (Hi, Implicit_Base);
14149 -- Analyze the range itself, except that we do not analyze it if
14150 -- the bounds are real literals, and we have a fixed-point type.
14151 -- The reason for this is that we delay setting the bounds in this
14152 -- case till we know the final Small and Size values (see circuit
14153 -- in Freeze.Freeze_Fixed_Point_Type for further details).
14155 if Is_Fixed_Point_Type (Parent_Type)
14156 and then Nkind (Lo) = N_Real_Literal
14157 and then Nkind (Hi) = N_Real_Literal
14161 -- Here we do the analysis of the range
14163 -- Note: we do this manually, since if we do a normal Analyze and
14164 -- Resolve call, there are problems with the conversions used for
14165 -- the derived type range.
14168 Set_Etype (Rng, Implicit_Base);
14169 Set_Analyzed (Rng, True);
14171 end Convert_Scalar_Bounds;
14173 -------------------
14174 -- Copy_And_Swap --
14175 -------------------
14177 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
14179 -- Initialize new full declaration entity by copying the pertinent
14180 -- fields of the corresponding private declaration entity.
14182 -- We temporarily set Ekind to a value appropriate for a type to
14183 -- avoid assert failures in Einfo from checking for setting type
14184 -- attributes on something that is not a type. Ekind (Priv) is an
14185 -- appropriate choice, since it allowed the attributes to be set
14186 -- in the first place. This Ekind value will be modified later.
14188 Set_Ekind (Full, Ekind (Priv));
14190 -- Also set Etype temporarily to Any_Type, again, in the absence
14191 -- of errors, it will be properly reset, and if there are errors,
14192 -- then we want a value of Any_Type to remain.
14194 Set_Etype (Full, Any_Type);
14196 -- Now start copying attributes
14198 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
14200 if Has_Discriminants (Full) then
14201 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
14202 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
14205 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
14206 Set_Homonym (Full, Homonym (Priv));
14207 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
14208 Set_Is_Public (Full, Is_Public (Priv));
14209 Set_Is_Pure (Full, Is_Pure (Priv));
14210 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
14211 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
14212 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
14213 Set_Has_Pragma_Unreferenced_Objects
14214 (Full, Has_Pragma_Unreferenced_Objects
14217 Conditional_Delay (Full, Priv);
14219 if Is_Tagged_Type (Full) then
14220 Set_Direct_Primitive_Operations
14221 (Full, Direct_Primitive_Operations (Priv));
14222 Set_No_Tagged_Streams_Pragma
14223 (Full, No_Tagged_Streams_Pragma (Priv));
14225 if Is_Base_Type (Priv) then
14226 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
14230 Set_Is_Volatile (Full, Is_Volatile (Priv));
14231 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
14232 Set_Scope (Full, Scope (Priv));
14233 Set_Next_Entity (Full, Next_Entity (Priv));
14234 Set_First_Entity (Full, First_Entity (Priv));
14235 Set_Last_Entity (Full, Last_Entity (Priv));
14237 -- If access types have been recorded for later handling, keep them in
14238 -- the full view so that they get handled when the full view freeze
14239 -- node is expanded.
14241 if Present (Freeze_Node (Priv))
14242 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
14244 Ensure_Freeze_Node (Full);
14245 Set_Access_Types_To_Process
14246 (Freeze_Node (Full),
14247 Access_Types_To_Process (Freeze_Node (Priv)));
14250 -- Swap the two entities. Now Private is the full type entity and Full
14251 -- is the private one. They will be swapped back at the end of the
14252 -- private part. This swapping ensures that the entity that is visible
14253 -- in the private part is the full declaration.
14255 Exchange_Entities (Priv, Full);
14256 Append_Entity (Full, Scope (Full));
14259 -------------------------------------
14260 -- Copy_Array_Base_Type_Attributes --
14261 -------------------------------------
14263 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
14265 Set_Component_Alignment (T1, Component_Alignment (T2));
14266 Set_Component_Type (T1, Component_Type (T2));
14267 Set_Component_Size (T1, Component_Size (T2));
14268 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
14269 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
14270 Propagate_Concurrent_Flags (T1, T2);
14271 Set_Is_Packed (T1, Is_Packed (T2));
14272 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
14273 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
14274 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
14275 end Copy_Array_Base_Type_Attributes;
14277 -----------------------------------
14278 -- Copy_Array_Subtype_Attributes --
14279 -----------------------------------
14281 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
14283 Set_Size_Info (T1, T2);
14285 Set_First_Index (T1, First_Index (T2));
14286 Set_Is_Aliased (T1, Is_Aliased (T2));
14287 Set_Is_Volatile (T1, Is_Volatile (T2));
14288 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
14289 Set_Is_Constrained (T1, Is_Constrained (T2));
14290 Set_Depends_On_Private (T1, Has_Private_Component (T2));
14291 Inherit_Rep_Item_Chain (T1, T2);
14292 Set_Convention (T1, Convention (T2));
14293 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
14294 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
14295 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
14296 end Copy_Array_Subtype_Attributes;
14298 -----------------------------------
14299 -- Create_Constrained_Components --
14300 -----------------------------------
14302 procedure Create_Constrained_Components
14304 Decl_Node : Node_Id;
14306 Constraints : Elist_Id)
14308 Loc : constant Source_Ptr := Sloc (Subt);
14309 Comp_List : constant Elist_Id := New_Elmt_List;
14310 Parent_Type : constant Entity_Id := Etype (Typ);
14311 Assoc_List : constant List_Id := New_List;
14312 Discr_Val : Elmt_Id;
14316 Is_Static : Boolean := True;
14318 procedure Collect_Fixed_Components (Typ : Entity_Id);
14319 -- Collect parent type components that do not appear in a variant part
14321 procedure Create_All_Components;
14322 -- Iterate over Comp_List to create the components of the subtype
14324 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
14325 -- Creates a new component from Old_Compon, copying all the fields from
14326 -- it, including its Etype, inserts the new component in the Subt entity
14327 -- chain and returns the new component.
14329 function Is_Variant_Record (T : Entity_Id) return Boolean;
14330 -- If true, and discriminants are static, collect only components from
14331 -- variants selected by discriminant values.
14333 ------------------------------
14334 -- Collect_Fixed_Components --
14335 ------------------------------
14337 procedure Collect_Fixed_Components (Typ : Entity_Id) is
14339 -- Build association list for discriminants, and find components of the
14340 -- variant part selected by the values of the discriminants.
14342 Old_C := First_Discriminant (Typ);
14343 Discr_Val := First_Elmt (Constraints);
14344 while Present (Old_C) loop
14345 Append_To (Assoc_List,
14346 Make_Component_Association (Loc,
14347 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
14348 Expression => New_Copy (Node (Discr_Val))));
14350 Next_Elmt (Discr_Val);
14351 Next_Discriminant (Old_C);
14354 -- The tag and the possible parent component are unconditionally in
14357 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
14358 Old_C := First_Component (Typ);
14359 while Present (Old_C) loop
14360 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
14361 Append_Elmt (Old_C, Comp_List);
14364 Next_Component (Old_C);
14367 end Collect_Fixed_Components;
14369 ---------------------------
14370 -- Create_All_Components --
14371 ---------------------------
14373 procedure Create_All_Components is
14377 Comp := First_Elmt (Comp_List);
14378 while Present (Comp) loop
14379 Old_C := Node (Comp);
14380 New_C := Create_Component (Old_C);
14384 Constrain_Component_Type
14385 (Old_C, Subt, Decl_Node, Typ, Constraints));
14386 Set_Is_Public (New_C, Is_Public (Subt));
14390 end Create_All_Components;
14392 ----------------------
14393 -- Create_Component --
14394 ----------------------
14396 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
14397 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
14400 if Ekind (Old_Compon) = E_Discriminant
14401 and then Is_Completely_Hidden (Old_Compon)
14403 -- This is a shadow discriminant created for a discriminant of
14404 -- the parent type, which needs to be present in the subtype.
14405 -- Give the shadow discriminant an internal name that cannot
14406 -- conflict with that of visible components.
14408 Set_Chars (New_Compon, New_Internal_Name ('C'));
14411 -- Set the parent so we have a proper link for freezing etc. This is
14412 -- not a real parent pointer, since of course our parent does not own
14413 -- up to us and reference us, we are an illegitimate child of the
14414 -- original parent.
14416 Set_Parent (New_Compon, Parent (Old_Compon));
14418 -- If the old component's Esize was already determined and is a
14419 -- static value, then the new component simply inherits it. Otherwise
14420 -- the old component's size may require run-time determination, but
14421 -- the new component's size still might be statically determinable
14422 -- (if, for example it has a static constraint). In that case we want
14423 -- Layout_Type to recompute the component's size, so we reset its
14424 -- size and positional fields.
14426 if Frontend_Layout_On_Target
14427 and then not Known_Static_Esize (Old_Compon)
14429 Set_Esize (New_Compon, Uint_0);
14430 Init_Normalized_First_Bit (New_Compon);
14431 Init_Normalized_Position (New_Compon);
14432 Init_Normalized_Position_Max (New_Compon);
14435 -- We do not want this node marked as Comes_From_Source, since
14436 -- otherwise it would get first class status and a separate cross-
14437 -- reference line would be generated. Illegitimate children do not
14438 -- rate such recognition.
14440 Set_Comes_From_Source (New_Compon, False);
14442 -- But it is a real entity, and a birth certificate must be properly
14443 -- registered by entering it into the entity list.
14445 Enter_Name (New_Compon);
14448 end Create_Component;
14450 -----------------------
14451 -- Is_Variant_Record --
14452 -----------------------
14454 function Is_Variant_Record (T : Entity_Id) return Boolean is
14456 return Nkind (Parent (T)) = N_Full_Type_Declaration
14457 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
14458 and then Present (Component_List (Type_Definition (Parent (T))))
14461 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
14462 end Is_Variant_Record;
14464 -- Start of processing for Create_Constrained_Components
14467 pragma Assert (Subt /= Base_Type (Subt));
14468 pragma Assert (Typ = Base_Type (Typ));
14470 Set_First_Entity (Subt, Empty);
14471 Set_Last_Entity (Subt, Empty);
14473 -- Check whether constraint is fully static, in which case we can
14474 -- optimize the list of components.
14476 Discr_Val := First_Elmt (Constraints);
14477 while Present (Discr_Val) loop
14478 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14479 Is_Static := False;
14483 Next_Elmt (Discr_Val);
14486 Set_Has_Static_Discriminants (Subt, Is_Static);
14490 -- Inherit the discriminants of the parent type
14492 Add_Discriminants : declare
14498 Old_C := First_Discriminant (Typ);
14500 while Present (Old_C) loop
14501 Num_Disc := Num_Disc + 1;
14502 New_C := Create_Component (Old_C);
14503 Set_Is_Public (New_C, Is_Public (Subt));
14504 Next_Discriminant (Old_C);
14507 -- For an untagged derived subtype, the number of discriminants may
14508 -- be smaller than the number of inherited discriminants, because
14509 -- several of them may be renamed by a single new discriminant or
14510 -- constrained. In this case, add the hidden discriminants back into
14511 -- the subtype, because they need to be present if the optimizer of
14512 -- the GCC 4.x back-end decides to break apart assignments between
14513 -- objects using the parent view into member-wise assignments.
14517 if Is_Derived_Type (Typ)
14518 and then not Is_Tagged_Type (Typ)
14520 Old_C := First_Stored_Discriminant (Typ);
14522 while Present (Old_C) loop
14523 Num_Gird := Num_Gird + 1;
14524 Next_Stored_Discriminant (Old_C);
14528 if Num_Gird > Num_Disc then
14530 -- Find out multiple uses of new discriminants, and add hidden
14531 -- components for the extra renamed discriminants. We recognize
14532 -- multiple uses through the Corresponding_Discriminant of a
14533 -- new discriminant: if it constrains several old discriminants,
14534 -- this field points to the last one in the parent type. The
14535 -- stored discriminants of the derived type have the same name
14536 -- as those of the parent.
14540 New_Discr : Entity_Id;
14541 Old_Discr : Entity_Id;
14544 Constr := First_Elmt (Stored_Constraint (Typ));
14545 Old_Discr := First_Stored_Discriminant (Typ);
14546 while Present (Constr) loop
14547 if Is_Entity_Name (Node (Constr))
14548 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14550 New_Discr := Entity (Node (Constr));
14552 if Chars (Corresponding_Discriminant (New_Discr)) /=
14555 -- The new discriminant has been used to rename a
14556 -- subsequent old discriminant. Introduce a shadow
14557 -- component for the current old discriminant.
14559 New_C := Create_Component (Old_Discr);
14560 Set_Original_Record_Component (New_C, Old_Discr);
14564 -- The constraint has eliminated the old discriminant.
14565 -- Introduce a shadow component.
14567 New_C := Create_Component (Old_Discr);
14568 Set_Original_Record_Component (New_C, Old_Discr);
14571 Next_Elmt (Constr);
14572 Next_Stored_Discriminant (Old_Discr);
14576 end Add_Discriminants;
14579 and then Is_Variant_Record (Typ)
14581 Collect_Fixed_Components (Typ);
14583 Gather_Components (
14585 Component_List (Type_Definition (Parent (Typ))),
14586 Governed_By => Assoc_List,
14588 Report_Errors => Errors);
14589 pragma Assert (not Errors
14590 or else Serious_Errors_Detected > 0);
14592 Create_All_Components;
14594 -- If the subtype declaration is created for a tagged type derivation
14595 -- with constraints, we retrieve the record definition of the parent
14596 -- type to select the components of the proper variant.
14599 and then Is_Tagged_Type (Typ)
14600 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14602 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14603 and then Is_Variant_Record (Parent_Type)
14605 Collect_Fixed_Components (Typ);
14609 Component_List (Type_Definition (Parent (Parent_Type))),
14610 Governed_By => Assoc_List,
14612 Report_Errors => Errors);
14614 -- Note: previously there was a check at this point that no errors
14615 -- were detected. As a consequence of AI05-220 there may be an error
14616 -- if an inherited discriminant that controls a variant has a non-
14617 -- static constraint.
14619 -- If the tagged derivation has a type extension, collect all the
14620 -- new components therein.
14622 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14624 Old_C := First_Component (Typ);
14625 while Present (Old_C) loop
14626 if Original_Record_Component (Old_C) = Old_C
14627 and then Chars (Old_C) /= Name_uTag
14628 and then Chars (Old_C) /= Name_uParent
14630 Append_Elmt (Old_C, Comp_List);
14633 Next_Component (Old_C);
14637 Create_All_Components;
14640 -- If discriminants are not static, or if this is a multi-level type
14641 -- extension, we have to include all components of the parent type.
14643 Old_C := First_Component (Typ);
14644 while Present (Old_C) loop
14645 New_C := Create_Component (Old_C);
14649 Constrain_Component_Type
14650 (Old_C, Subt, Decl_Node, Typ, Constraints));
14651 Set_Is_Public (New_C, Is_Public (Subt));
14653 Next_Component (Old_C);
14658 end Create_Constrained_Components;
14660 ------------------------------------------
14661 -- Decimal_Fixed_Point_Type_Declaration --
14662 ------------------------------------------
14664 procedure Decimal_Fixed_Point_Type_Declaration
14668 Loc : constant Source_Ptr := Sloc (Def);
14669 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14670 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14671 Implicit_Base : Entity_Id;
14678 Check_SPARK_05_Restriction
14679 ("decimal fixed point type is not allowed", Def);
14680 Check_Restriction (No_Fixed_Point, Def);
14682 -- Create implicit base type
14685 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14686 Set_Etype (Implicit_Base, Implicit_Base);
14688 -- Analyze and process delta expression
14690 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14692 Check_Delta_Expression (Delta_Expr);
14693 Delta_Val := Expr_Value_R (Delta_Expr);
14695 -- Check delta is power of 10, and determine scale value from it
14701 Scale_Val := Uint_0;
14704 if Val < Ureal_1 then
14705 while Val < Ureal_1 loop
14706 Val := Val * Ureal_10;
14707 Scale_Val := Scale_Val + 1;
14710 if Scale_Val > 18 then
14711 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14712 Scale_Val := UI_From_Int (+18);
14716 while Val > Ureal_1 loop
14717 Val := Val / Ureal_10;
14718 Scale_Val := Scale_Val - 1;
14721 if Scale_Val < -18 then
14722 Error_Msg_N ("scale is less than minimum value of -18", Def);
14723 Scale_Val := UI_From_Int (-18);
14727 if Val /= Ureal_1 then
14728 Error_Msg_N ("delta expression must be a power of 10", Def);
14729 Delta_Val := Ureal_10 ** (-Scale_Val);
14733 -- Set delta, scale and small (small = delta for decimal type)
14735 Set_Delta_Value (Implicit_Base, Delta_Val);
14736 Set_Scale_Value (Implicit_Base, Scale_Val);
14737 Set_Small_Value (Implicit_Base, Delta_Val);
14739 -- Analyze and process digits expression
14741 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14742 Check_Digits_Expression (Digs_Expr);
14743 Digs_Val := Expr_Value (Digs_Expr);
14745 if Digs_Val > 18 then
14746 Digs_Val := UI_From_Int (+18);
14747 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14750 Set_Digits_Value (Implicit_Base, Digs_Val);
14751 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14753 -- Set range of base type from digits value for now. This will be
14754 -- expanded to represent the true underlying base range by Freeze.
14756 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14758 -- Note: We leave size as zero for now, size will be set at freeze
14759 -- time. We have to do this for ordinary fixed-point, because the size
14760 -- depends on the specified small, and we might as well do the same for
14761 -- decimal fixed-point.
14763 pragma Assert (Esize (Implicit_Base) = Uint_0);
14765 -- If there are bounds given in the declaration use them as the
14766 -- bounds of the first named subtype.
14768 if Present (Real_Range_Specification (Def)) then
14770 RRS : constant Node_Id := Real_Range_Specification (Def);
14771 Low : constant Node_Id := Low_Bound (RRS);
14772 High : constant Node_Id := High_Bound (RRS);
14777 Analyze_And_Resolve (Low, Any_Real);
14778 Analyze_And_Resolve (High, Any_Real);
14779 Check_Real_Bound (Low);
14780 Check_Real_Bound (High);
14781 Low_Val := Expr_Value_R (Low);
14782 High_Val := Expr_Value_R (High);
14784 if Low_Val < (-Bound_Val) then
14786 ("range low bound too small for digits value", Low);
14787 Low_Val := -Bound_Val;
14790 if High_Val > Bound_Val then
14792 ("range high bound too large for digits value", High);
14793 High_Val := Bound_Val;
14796 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14799 -- If no explicit range, use range that corresponds to given
14800 -- digits value. This will end up as the final range for the
14804 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14807 -- Complete entity for first subtype. The inheritance of the rep item
14808 -- chain ensures that SPARK-related pragmas are not clobbered when the
14809 -- decimal fixed point type acts as a full view of a private type.
14811 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14812 Set_Etype (T, Implicit_Base);
14813 Set_Size_Info (T, Implicit_Base);
14814 Inherit_Rep_Item_Chain (T, Implicit_Base);
14815 Set_Digits_Value (T, Digs_Val);
14816 Set_Delta_Value (T, Delta_Val);
14817 Set_Small_Value (T, Delta_Val);
14818 Set_Scale_Value (T, Scale_Val);
14819 Set_Is_Constrained (T);
14820 end Decimal_Fixed_Point_Type_Declaration;
14822 -----------------------------------
14823 -- Derive_Progenitor_Subprograms --
14824 -----------------------------------
14826 procedure Derive_Progenitor_Subprograms
14827 (Parent_Type : Entity_Id;
14828 Tagged_Type : Entity_Id)
14833 Iface_Elmt : Elmt_Id;
14834 Iface_Subp : Entity_Id;
14835 New_Subp : Entity_Id := Empty;
14836 Prim_Elmt : Elmt_Id;
14841 pragma Assert (Ada_Version >= Ada_2005
14842 and then Is_Record_Type (Tagged_Type)
14843 and then Is_Tagged_Type (Tagged_Type)
14844 and then Has_Interfaces (Tagged_Type));
14846 -- Step 1: Transfer to the full-view primitives associated with the
14847 -- partial-view that cover interface primitives. Conceptually this
14848 -- work should be done later by Process_Full_View; done here to
14849 -- simplify its implementation at later stages. It can be safely
14850 -- done here because interfaces must be visible in the partial and
14851 -- private view (RM 7.3(7.3/2)).
14853 -- Small optimization: This work is only required if the parent may
14854 -- have entities whose Alias attribute reference an interface primitive.
14855 -- Such a situation may occur if the parent is an abstract type and the
14856 -- primitive has not been yet overridden or if the parent is a generic
14857 -- formal type covering interfaces.
14859 -- If the tagged type is not abstract, it cannot have abstract
14860 -- primitives (the only entities in the list of primitives of
14861 -- non-abstract tagged types that can reference abstract primitives
14862 -- through its Alias attribute are the internal entities that have
14863 -- attribute Interface_Alias, and these entities are generated later
14864 -- by Add_Internal_Interface_Entities).
14866 if In_Private_Part (Current_Scope)
14867 and then (Is_Abstract_Type (Parent_Type)
14869 Is_Generic_Type (Parent_Type))
14871 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14872 while Present (Elmt) loop
14873 Subp := Node (Elmt);
14875 -- At this stage it is not possible to have entities in the list
14876 -- of primitives that have attribute Interface_Alias.
14878 pragma Assert (No (Interface_Alias (Subp)));
14880 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14882 if Is_Interface (Typ) then
14883 E := Find_Primitive_Covering_Interface
14884 (Tagged_Type => Tagged_Type,
14885 Iface_Prim => Subp);
14888 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14890 Replace_Elmt (Elmt, E);
14891 Remove_Homonym (Subp);
14899 -- Step 2: Add primitives of progenitors that are not implemented by
14900 -- parents of Tagged_Type.
14902 if Present (Interfaces (Base_Type (Tagged_Type))) then
14903 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14904 while Present (Iface_Elmt) loop
14905 Iface := Node (Iface_Elmt);
14907 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14908 while Present (Prim_Elmt) loop
14909 Iface_Subp := Node (Prim_Elmt);
14911 -- Exclude derivation of predefined primitives except those
14912 -- that come from source, or are inherited from one that comes
14913 -- from source. Required to catch declarations of equality
14914 -- operators of interfaces. For example:
14916 -- type Iface is interface;
14917 -- function "=" (Left, Right : Iface) return Boolean;
14919 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14920 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14922 E := Find_Primitive_Covering_Interface
14923 (Tagged_Type => Tagged_Type,
14924 Iface_Prim => Iface_Subp);
14926 -- If not found we derive a new primitive leaving its alias
14927 -- attribute referencing the interface primitive.
14931 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14933 -- Ada 2012 (AI05-0197): If the covering primitive's name
14934 -- differs from the name of the interface primitive then it
14935 -- is a private primitive inherited from a parent type. In
14936 -- such case, given that Tagged_Type covers the interface,
14937 -- the inherited private primitive becomes visible. For such
14938 -- purpose we add a new entity that renames the inherited
14939 -- private primitive.
14941 elsif Chars (E) /= Chars (Iface_Subp) then
14942 pragma Assert (Has_Suffix (E, 'P'));
14944 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14945 Set_Alias (New_Subp, E);
14946 Set_Is_Abstract_Subprogram (New_Subp,
14947 Is_Abstract_Subprogram (E));
14949 -- Propagate to the full view interface entities associated
14950 -- with the partial view.
14952 elsif In_Private_Part (Current_Scope)
14953 and then Present (Alias (E))
14954 and then Alias (E) = Iface_Subp
14956 List_Containing (Parent (E)) /=
14957 Private_Declarations
14959 (Unit_Declaration_Node (Current_Scope)))
14961 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14965 Next_Elmt (Prim_Elmt);
14968 Next_Elmt (Iface_Elmt);
14971 end Derive_Progenitor_Subprograms;
14973 -----------------------
14974 -- Derive_Subprogram --
14975 -----------------------
14977 procedure Derive_Subprogram
14978 (New_Subp : out Entity_Id;
14979 Parent_Subp : Entity_Id;
14980 Derived_Type : Entity_Id;
14981 Parent_Type : Entity_Id;
14982 Actual_Subp : Entity_Id := Empty)
14984 Formal : Entity_Id;
14985 -- Formal parameter of parent primitive operation
14987 Formal_Of_Actual : Entity_Id;
14988 -- Formal parameter of actual operation, when the derivation is to
14989 -- create a renaming for a primitive operation of an actual in an
14992 New_Formal : Entity_Id;
14993 -- Formal of inherited operation
14995 Visible_Subp : Entity_Id := Parent_Subp;
14997 function Is_Private_Overriding return Boolean;
14998 -- If Subp is a private overriding of a visible operation, the inherited
14999 -- operation derives from the overridden op (even though its body is the
15000 -- overriding one) and the inherited operation is visible now. See
15001 -- sem_disp to see the full details of the handling of the overridden
15002 -- subprogram, which is removed from the list of primitive operations of
15003 -- the type. The overridden subprogram is saved locally in Visible_Subp,
15004 -- and used to diagnose abstract operations that need overriding in the
15007 procedure Replace_Type (Id, New_Id : Entity_Id);
15008 -- When the type is an anonymous access type, create a new access type
15009 -- designating the derived type.
15011 procedure Set_Derived_Name;
15012 -- This procedure sets the appropriate Chars name for New_Subp. This
15013 -- is normally just a copy of the parent name. An exception arises for
15014 -- type support subprograms, where the name is changed to reflect the
15015 -- name of the derived type, e.g. if type foo is derived from type bar,
15016 -- then a procedure barDA is derived with a name fooDA.
15018 ---------------------------
15019 -- Is_Private_Overriding --
15020 ---------------------------
15022 function Is_Private_Overriding return Boolean is
15026 -- If the parent is not a dispatching operation there is no
15027 -- need to investigate overridings
15029 if not Is_Dispatching_Operation (Parent_Subp) then
15033 -- The visible operation that is overridden is a homonym of the
15034 -- parent subprogram. We scan the homonym chain to find the one
15035 -- whose alias is the subprogram we are deriving.
15037 Prev := Current_Entity (Parent_Subp);
15038 while Present (Prev) loop
15039 if Ekind (Prev) = Ekind (Parent_Subp)
15040 and then Alias (Prev) = Parent_Subp
15041 and then Scope (Parent_Subp) = Scope (Prev)
15042 and then not Is_Hidden (Prev)
15044 Visible_Subp := Prev;
15048 Prev := Homonym (Prev);
15052 end Is_Private_Overriding;
15058 procedure Replace_Type (Id, New_Id : Entity_Id) is
15059 Id_Type : constant Entity_Id := Etype (Id);
15060 Acc_Type : Entity_Id;
15061 Par : constant Node_Id := Parent (Derived_Type);
15064 -- When the type is an anonymous access type, create a new access
15065 -- type designating the derived type. This itype must be elaborated
15066 -- at the point of the derivation, not on subsequent calls that may
15067 -- be out of the proper scope for Gigi, so we insert a reference to
15068 -- it after the derivation.
15070 if Ekind (Id_Type) = E_Anonymous_Access_Type then
15072 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
15075 if Ekind (Desig_Typ) = E_Record_Type_With_Private
15076 and then Present (Full_View (Desig_Typ))
15077 and then not Is_Private_Type (Parent_Type)
15079 Desig_Typ := Full_View (Desig_Typ);
15082 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
15084 -- Ada 2005 (AI-251): Handle also derivations of abstract
15085 -- interface primitives.
15087 or else (Is_Interface (Desig_Typ)
15088 and then not Is_Class_Wide_Type (Desig_Typ))
15090 Acc_Type := New_Copy (Id_Type);
15091 Set_Etype (Acc_Type, Acc_Type);
15092 Set_Scope (Acc_Type, New_Subp);
15094 -- Set size of anonymous access type. If we have an access
15095 -- to an unconstrained array, this is a fat pointer, so it
15096 -- is sizes at twice addtress size.
15098 if Is_Array_Type (Desig_Typ)
15099 and then not Is_Constrained (Desig_Typ)
15101 Init_Size (Acc_Type, 2 * System_Address_Size);
15103 -- Other cases use a thin pointer
15106 Init_Size (Acc_Type, System_Address_Size);
15109 -- Set remaining characterstics of anonymous access type
15111 Init_Alignment (Acc_Type);
15112 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
15114 Set_Etype (New_Id, Acc_Type);
15115 Set_Scope (New_Id, New_Subp);
15117 -- Create a reference to it
15119 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
15122 Set_Etype (New_Id, Id_Type);
15126 -- In Ada2012, a formal may have an incomplete type but the type
15127 -- derivation that inherits the primitive follows the full view.
15129 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
15131 (Ekind (Id_Type) = E_Record_Type_With_Private
15132 and then Present (Full_View (Id_Type))
15134 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
15136 (Ada_Version >= Ada_2012
15137 and then Ekind (Id_Type) = E_Incomplete_Type
15138 and then Full_View (Id_Type) = Parent_Type)
15140 -- Constraint checks on formals are generated during expansion,
15141 -- based on the signature of the original subprogram. The bounds
15142 -- of the derived type are not relevant, and thus we can use
15143 -- the base type for the formals. However, the return type may be
15144 -- used in a context that requires that the proper static bounds
15145 -- be used (a case statement, for example) and for those cases
15146 -- we must use the derived type (first subtype), not its base.
15148 -- If the derived_type_definition has no constraints, we know that
15149 -- the derived type has the same constraints as the first subtype
15150 -- of the parent, and we can also use it rather than its base,
15151 -- which can lead to more efficient code.
15153 if Etype (Id) = Parent_Type then
15154 if Is_Scalar_Type (Parent_Type)
15156 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
15158 Set_Etype (New_Id, Derived_Type);
15160 elsif Nkind (Par) = N_Full_Type_Declaration
15162 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
15165 (Subtype_Indication (Type_Definition (Par)))
15167 Set_Etype (New_Id, Derived_Type);
15170 Set_Etype (New_Id, Base_Type (Derived_Type));
15174 Set_Etype (New_Id, Base_Type (Derived_Type));
15178 Set_Etype (New_Id, Etype (Id));
15182 ----------------------
15183 -- Set_Derived_Name --
15184 ----------------------
15186 procedure Set_Derived_Name is
15187 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
15189 if Nm = TSS_Null then
15190 Set_Chars (New_Subp, Chars (Parent_Subp));
15192 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
15194 end Set_Derived_Name;
15196 -- Start of processing for Derive_Subprogram
15199 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
15200 Set_Ekind (New_Subp, Ekind (Parent_Subp));
15202 -- Check whether the inherited subprogram is a private operation that
15203 -- should be inherited but not yet made visible. Such subprograms can
15204 -- become visible at a later point (e.g., the private part of a public
15205 -- child unit) via Declare_Inherited_Private_Subprograms. If the
15206 -- following predicate is true, then this is not such a private
15207 -- operation and the subprogram simply inherits the name of the parent
15208 -- subprogram. Note the special check for the names of controlled
15209 -- operations, which are currently exempted from being inherited with
15210 -- a hidden name because they must be findable for generation of
15211 -- implicit run-time calls.
15213 if not Is_Hidden (Parent_Subp)
15214 or else Is_Internal (Parent_Subp)
15215 or else Is_Private_Overriding
15216 or else Is_Internal_Name (Chars (Parent_Subp))
15217 or else (Is_Controlled (Parent_Type)
15218 and then Nam_In (Chars (Parent_Subp), Name_Adjust,
15224 -- An inherited dispatching equality will be overridden by an internally
15225 -- generated one, or by an explicit one, so preserve its name and thus
15226 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
15227 -- private operation it may become invisible if the full view has
15228 -- progenitors, and the dispatch table will be malformed.
15229 -- We check that the type is limited to handle the anomalous declaration
15230 -- of Limited_Controlled, which is derived from a non-limited type, and
15231 -- which is handled specially elsewhere as well.
15233 elsif Chars (Parent_Subp) = Name_Op_Eq
15234 and then Is_Dispatching_Operation (Parent_Subp)
15235 and then Etype (Parent_Subp) = Standard_Boolean
15236 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
15238 Etype (First_Formal (Parent_Subp)) =
15239 Etype (Next_Formal (First_Formal (Parent_Subp)))
15243 -- If parent is hidden, this can be a regular derivation if the
15244 -- parent is immediately visible in a non-instantiating context,
15245 -- or if we are in the private part of an instance. This test
15246 -- should still be refined ???
15248 -- The test for In_Instance_Not_Visible avoids inheriting the derived
15249 -- operation as a non-visible operation in cases where the parent
15250 -- subprogram might not be visible now, but was visible within the
15251 -- original generic, so it would be wrong to make the inherited
15252 -- subprogram non-visible now. (Not clear if this test is fully
15253 -- correct; are there any cases where we should declare the inherited
15254 -- operation as not visible to avoid it being overridden, e.g., when
15255 -- the parent type is a generic actual with private primitives ???)
15257 -- (they should be treated the same as other private inherited
15258 -- subprograms, but it's not clear how to do this cleanly). ???
15260 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15261 and then Is_Immediately_Visible (Parent_Subp)
15262 and then not In_Instance)
15263 or else In_Instance_Not_Visible
15267 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
15268 -- overrides an interface primitive because interface primitives
15269 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
15271 elsif Ada_Version >= Ada_2005
15272 and then Is_Dispatching_Operation (Parent_Subp)
15273 and then Present (Covered_Interface_Op (Parent_Subp))
15277 -- Otherwise, the type is inheriting a private operation, so enter it
15278 -- with a special name so it can't be overridden.
15281 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
15284 Set_Parent (New_Subp, Parent (Derived_Type));
15286 if Present (Actual_Subp) then
15287 Replace_Type (Actual_Subp, New_Subp);
15289 Replace_Type (Parent_Subp, New_Subp);
15292 Conditional_Delay (New_Subp, Parent_Subp);
15294 -- If we are creating a renaming for a primitive operation of an
15295 -- actual of a generic derived type, we must examine the signature
15296 -- of the actual primitive, not that of the generic formal, which for
15297 -- example may be an interface. However the name and initial value
15298 -- of the inherited operation are those of the formal primitive.
15300 Formal := First_Formal (Parent_Subp);
15302 if Present (Actual_Subp) then
15303 Formal_Of_Actual := First_Formal (Actual_Subp);
15305 Formal_Of_Actual := Empty;
15308 while Present (Formal) loop
15309 New_Formal := New_Copy (Formal);
15311 -- Normally we do not go copying parents, but in the case of
15312 -- formals, we need to link up to the declaration (which is the
15313 -- parameter specification), and it is fine to link up to the
15314 -- original formal's parameter specification in this case.
15316 Set_Parent (New_Formal, Parent (Formal));
15317 Append_Entity (New_Formal, New_Subp);
15319 if Present (Formal_Of_Actual) then
15320 Replace_Type (Formal_Of_Actual, New_Formal);
15321 Next_Formal (Formal_Of_Actual);
15323 Replace_Type (Formal, New_Formal);
15326 Next_Formal (Formal);
15329 -- If this derivation corresponds to a tagged generic actual, then
15330 -- primitive operations rename those of the actual. Otherwise the
15331 -- primitive operations rename those of the parent type, If the parent
15332 -- renames an intrinsic operator, so does the new subprogram. We except
15333 -- concatenation, which is always properly typed, and does not get
15334 -- expanded as other intrinsic operations.
15336 if No (Actual_Subp) then
15337 if Is_Intrinsic_Subprogram (Parent_Subp) then
15338 Set_Is_Intrinsic_Subprogram (New_Subp);
15340 if Present (Alias (Parent_Subp))
15341 and then Chars (Parent_Subp) /= Name_Op_Concat
15343 Set_Alias (New_Subp, Alias (Parent_Subp));
15345 Set_Alias (New_Subp, Parent_Subp);
15349 Set_Alias (New_Subp, Parent_Subp);
15353 Set_Alias (New_Subp, Actual_Subp);
15356 -- Derived subprograms of a tagged type must inherit the convention
15357 -- of the parent subprogram (a requirement of AI-117). Derived
15358 -- subprograms of untagged types simply get convention Ada by default.
15360 -- If the derived type is a tagged generic formal type with unknown
15361 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
15363 -- However, if the type is derived from a generic formal, the further
15364 -- inherited subprogram has the convention of the non-generic ancestor.
15365 -- Otherwise there would be no way to override the operation.
15366 -- (This is subject to forthcoming ARG discussions).
15368 if Is_Tagged_Type (Derived_Type) then
15369 if Is_Generic_Type (Derived_Type)
15370 and then Has_Unknown_Discriminants (Derived_Type)
15372 Set_Convention (New_Subp, Convention_Intrinsic);
15375 if Is_Generic_Type (Parent_Type)
15376 and then Has_Unknown_Discriminants (Parent_Type)
15378 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
15380 Set_Convention (New_Subp, Convention (Parent_Subp));
15385 -- Predefined controlled operations retain their name even if the parent
15386 -- is hidden (see above), but they are not primitive operations if the
15387 -- ancestor is not visible, for example if the parent is a private
15388 -- extension completed with a controlled extension. Note that a full
15389 -- type that is controlled can break privacy: the flag Is_Controlled is
15390 -- set on both views of the type.
15392 if Is_Controlled (Parent_Type)
15393 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
15396 and then Is_Hidden (Parent_Subp)
15397 and then not Is_Visibly_Controlled (Parent_Type)
15399 Set_Is_Hidden (New_Subp);
15402 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
15403 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
15405 if Ekind (Parent_Subp) = E_Procedure then
15406 Set_Is_Valued_Procedure
15407 (New_Subp, Is_Valued_Procedure (Parent_Subp));
15409 Set_Has_Controlling_Result
15410 (New_Subp, Has_Controlling_Result (Parent_Subp));
15413 -- No_Return must be inherited properly. If this is overridden in the
15414 -- case of a dispatching operation, then a check is made in Sem_Disp
15415 -- that the overriding operation is also No_Return (no such check is
15416 -- required for the case of non-dispatching operation.
15418 Set_No_Return (New_Subp, No_Return (Parent_Subp));
15420 -- A derived function with a controlling result is abstract. If the
15421 -- Derived_Type is a nonabstract formal generic derived type, then
15422 -- inherited operations are not abstract: the required check is done at
15423 -- instantiation time. If the derivation is for a generic actual, the
15424 -- function is not abstract unless the actual is.
15426 if Is_Generic_Type (Derived_Type)
15427 and then not Is_Abstract_Type (Derived_Type)
15431 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
15432 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
15434 -- A subprogram subject to pragma Extensions_Visible with value False
15435 -- requires overriding if the subprogram has at least one controlling
15436 -- OUT parameter (SPARK RM 6.1.7(6)).
15438 elsif Ada_Version >= Ada_2005
15439 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15440 or else (Is_Tagged_Type (Derived_Type)
15441 and then Etype (New_Subp) = Derived_Type
15442 and then not Is_Null_Extension (Derived_Type))
15443 or else (Is_Tagged_Type (Derived_Type)
15444 and then Ekind (Etype (New_Subp)) =
15445 E_Anonymous_Access_Type
15446 and then Designated_Type (Etype (New_Subp)) =
15448 and then not Is_Null_Extension (Derived_Type))
15449 or else (Comes_From_Source (Alias (New_Subp))
15450 and then Is_EVF_Procedure (Alias (New_Subp))))
15451 and then No (Actual_Subp)
15453 if not Is_Tagged_Type (Derived_Type)
15454 or else Is_Abstract_Type (Derived_Type)
15455 or else Is_Abstract_Subprogram (Alias (New_Subp))
15457 Set_Is_Abstract_Subprogram (New_Subp);
15459 Set_Requires_Overriding (New_Subp);
15462 elsif Ada_Version < Ada_2005
15463 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15464 or else (Is_Tagged_Type (Derived_Type)
15465 and then Etype (New_Subp) = Derived_Type
15466 and then No (Actual_Subp)))
15468 Set_Is_Abstract_Subprogram (New_Subp);
15470 -- AI05-0097 : an inherited operation that dispatches on result is
15471 -- abstract if the derived type is abstract, even if the parent type
15472 -- is concrete and the derived type is a null extension.
15474 elsif Has_Controlling_Result (Alias (New_Subp))
15475 and then Is_Abstract_Type (Etype (New_Subp))
15477 Set_Is_Abstract_Subprogram (New_Subp);
15479 -- Finally, if the parent type is abstract we must verify that all
15480 -- inherited operations are either non-abstract or overridden, or that
15481 -- the derived type itself is abstract (this check is performed at the
15482 -- end of a package declaration, in Check_Abstract_Overriding). A
15483 -- private overriding in the parent type will not be visible in the
15484 -- derivation if we are not in an inner package or in a child unit of
15485 -- the parent type, in which case the abstractness of the inherited
15486 -- operation is carried to the new subprogram.
15488 elsif Is_Abstract_Type (Parent_Type)
15489 and then not In_Open_Scopes (Scope (Parent_Type))
15490 and then Is_Private_Overriding
15491 and then Is_Abstract_Subprogram (Visible_Subp)
15493 if No (Actual_Subp) then
15494 Set_Alias (New_Subp, Visible_Subp);
15495 Set_Is_Abstract_Subprogram (New_Subp, True);
15498 -- If this is a derivation for an instance of a formal derived
15499 -- type, abstractness comes from the primitive operation of the
15500 -- actual, not from the operation inherited from the ancestor.
15502 Set_Is_Abstract_Subprogram
15503 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15507 New_Overloaded_Entity (New_Subp, Derived_Type);
15509 -- Ada RM 6.1.1 (15): If a subprogram inherits nonconforming class-wide
15510 -- preconditions and the derived type is abstract, the derived operation
15511 -- is abstract as well if parent subprogram is not abstract or null.
15513 if Is_Abstract_Type (Derived_Type)
15514 and then Has_Non_Trivial_Precondition (Parent_Subp)
15515 and then Present (Interfaces (Derived_Type))
15518 -- Add useful attributes of subprogram before the freeze point,
15519 -- in case freezing is delayed or there are previous errors.
15521 Set_Is_Dispatching_Operation (New_Subp);
15524 Iface_Prim : constant Entity_Id := Covered_Interface_Op (New_Subp);
15527 if Present (Iface_Prim)
15528 and then Has_Non_Trivial_Precondition (Iface_Prim)
15530 Set_Is_Abstract_Subprogram (New_Subp);
15535 -- Check for case of a derived subprogram for the instantiation of a
15536 -- formal derived tagged type, if so mark the subprogram as dispatching
15537 -- and inherit the dispatching attributes of the actual subprogram. The
15538 -- derived subprogram is effectively renaming of the actual subprogram,
15539 -- so it needs to have the same attributes as the actual.
15541 if Present (Actual_Subp)
15542 and then Is_Dispatching_Operation (Actual_Subp)
15544 Set_Is_Dispatching_Operation (New_Subp);
15546 if Present (DTC_Entity (Actual_Subp)) then
15547 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15548 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15552 -- Indicate that a derived subprogram does not require a body and that
15553 -- it does not require processing of default expressions.
15555 Set_Has_Completion (New_Subp);
15556 Set_Default_Expressions_Processed (New_Subp);
15558 if Ekind (New_Subp) = E_Function then
15559 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15561 end Derive_Subprogram;
15563 ------------------------
15564 -- Derive_Subprograms --
15565 ------------------------
15567 procedure Derive_Subprograms
15568 (Parent_Type : Entity_Id;
15569 Derived_Type : Entity_Id;
15570 Generic_Actual : Entity_Id := Empty)
15572 Op_List : constant Elist_Id :=
15573 Collect_Primitive_Operations (Parent_Type);
15575 function Check_Derived_Type return Boolean;
15576 -- Check that all the entities derived from Parent_Type are found in
15577 -- the list of primitives of Derived_Type exactly in the same order.
15579 procedure Derive_Interface_Subprogram
15580 (New_Subp : out Entity_Id;
15582 Actual_Subp : Entity_Id);
15583 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15584 -- (which is an interface primitive). If Generic_Actual is present then
15585 -- Actual_Subp is the actual subprogram corresponding with the generic
15586 -- subprogram Subp.
15588 ------------------------
15589 -- Check_Derived_Type --
15590 ------------------------
15592 function Check_Derived_Type return Boolean is
15596 New_Subp : Entity_Id;
15601 -- Traverse list of entities in the current scope searching for
15602 -- an incomplete type whose full-view is derived type.
15604 E := First_Entity (Scope (Derived_Type));
15605 while Present (E) and then E /= Derived_Type loop
15606 if Ekind (E) = E_Incomplete_Type
15607 and then Present (Full_View (E))
15608 and then Full_View (E) = Derived_Type
15610 -- Disable this test if Derived_Type completes an incomplete
15611 -- type because in such case more primitives can be added
15612 -- later to the list of primitives of Derived_Type by routine
15613 -- Process_Incomplete_Dependents
15618 E := Next_Entity (E);
15621 List := Collect_Primitive_Operations (Derived_Type);
15622 Elmt := First_Elmt (List);
15624 Op_Elmt := First_Elmt (Op_List);
15625 while Present (Op_Elmt) loop
15626 Subp := Node (Op_Elmt);
15627 New_Subp := Node (Elmt);
15629 -- At this early stage Derived_Type has no entities with attribute
15630 -- Interface_Alias. In addition, such primitives are always
15631 -- located at the end of the list of primitives of Parent_Type.
15632 -- Therefore, if found we can safely stop processing pending
15635 exit when Present (Interface_Alias (Subp));
15637 -- Handle hidden entities
15639 if not Is_Predefined_Dispatching_Operation (Subp)
15640 and then Is_Hidden (Subp)
15642 if Present (New_Subp)
15643 and then Primitive_Names_Match (Subp, New_Subp)
15649 if not Present (New_Subp)
15650 or else Ekind (Subp) /= Ekind (New_Subp)
15651 or else not Primitive_Names_Match (Subp, New_Subp)
15659 Next_Elmt (Op_Elmt);
15663 end Check_Derived_Type;
15665 ---------------------------------
15666 -- Derive_Interface_Subprogram --
15667 ---------------------------------
15669 procedure Derive_Interface_Subprogram
15670 (New_Subp : out Entity_Id;
15672 Actual_Subp : Entity_Id)
15674 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15675 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15678 pragma Assert (Is_Interface (Iface_Type));
15681 (New_Subp => New_Subp,
15682 Parent_Subp => Iface_Subp,
15683 Derived_Type => Derived_Type,
15684 Parent_Type => Iface_Type,
15685 Actual_Subp => Actual_Subp);
15687 -- Given that this new interface entity corresponds with a primitive
15688 -- of the parent that was not overridden we must leave it associated
15689 -- with its parent primitive to ensure that it will share the same
15690 -- dispatch table slot when overridden. We must set the Alias to Subp
15691 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15692 -- (in case we inherited Subp from Iface_Type via a nonabstract
15693 -- generic formal type).
15695 if No (Actual_Subp) then
15696 Set_Alias (New_Subp, Subp);
15699 T : Entity_Id := Find_Dispatching_Type (Subp);
15701 while Etype (T) /= T loop
15702 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15703 Set_Is_Abstract_Subprogram (New_Subp, False);
15711 -- For instantiations this is not needed since the previous call to
15712 -- Derive_Subprogram leaves the entity well decorated.
15715 pragma Assert (Alias (New_Subp) = Actual_Subp);
15718 end Derive_Interface_Subprogram;
15722 Alias_Subp : Entity_Id;
15723 Act_List : Elist_Id;
15724 Act_Elmt : Elmt_Id;
15725 Act_Subp : Entity_Id := Empty;
15727 Need_Search : Boolean := False;
15728 New_Subp : Entity_Id := Empty;
15729 Parent_Base : Entity_Id;
15732 -- Start of processing for Derive_Subprograms
15735 if Ekind (Parent_Type) = E_Record_Type_With_Private
15736 and then Has_Discriminants (Parent_Type)
15737 and then Present (Full_View (Parent_Type))
15739 Parent_Base := Full_View (Parent_Type);
15741 Parent_Base := Parent_Type;
15744 if Present (Generic_Actual) then
15745 Act_List := Collect_Primitive_Operations (Generic_Actual);
15746 Act_Elmt := First_Elmt (Act_List);
15748 Act_List := No_Elist;
15749 Act_Elmt := No_Elmt;
15752 -- Derive primitives inherited from the parent. Note that if the generic
15753 -- actual is present, this is not really a type derivation, it is a
15754 -- completion within an instance.
15756 -- Case 1: Derived_Type does not implement interfaces
15758 if not Is_Tagged_Type (Derived_Type)
15759 or else (not Has_Interfaces (Derived_Type)
15760 and then not (Present (Generic_Actual)
15761 and then Has_Interfaces (Generic_Actual)))
15763 Elmt := First_Elmt (Op_List);
15764 while Present (Elmt) loop
15765 Subp := Node (Elmt);
15767 -- Literals are derived earlier in the process of building the
15768 -- derived type, and are skipped here.
15770 if Ekind (Subp) = E_Enumeration_Literal then
15773 -- The actual is a direct descendant and the common primitive
15774 -- operations appear in the same order.
15776 -- If the generic parent type is present, the derived type is an
15777 -- instance of a formal derived type, and within the instance its
15778 -- operations are those of the actual. We derive from the formal
15779 -- type but make the inherited operations aliases of the
15780 -- corresponding operations of the actual.
15783 pragma Assert (No (Node (Act_Elmt))
15784 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15787 (Subp, Node (Act_Elmt),
15788 Skip_Controlling_Formals => True)));
15791 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15793 if Present (Act_Elmt) then
15794 Next_Elmt (Act_Elmt);
15801 -- Case 2: Derived_Type implements interfaces
15804 -- If the parent type has no predefined primitives we remove
15805 -- predefined primitives from the list of primitives of generic
15806 -- actual to simplify the complexity of this algorithm.
15808 if Present (Generic_Actual) then
15810 Has_Predefined_Primitives : Boolean := False;
15813 -- Check if the parent type has predefined primitives
15815 Elmt := First_Elmt (Op_List);
15816 while Present (Elmt) loop
15817 Subp := Node (Elmt);
15819 if Is_Predefined_Dispatching_Operation (Subp)
15820 and then not Comes_From_Source (Ultimate_Alias (Subp))
15822 Has_Predefined_Primitives := True;
15829 -- Remove predefined primitives of Generic_Actual. We must use
15830 -- an auxiliary list because in case of tagged types the value
15831 -- returned by Collect_Primitive_Operations is the value stored
15832 -- in its Primitive_Operations attribute (and we don't want to
15833 -- modify its current contents).
15835 if not Has_Predefined_Primitives then
15837 Aux_List : constant Elist_Id := New_Elmt_List;
15840 Elmt := First_Elmt (Act_List);
15841 while Present (Elmt) loop
15842 Subp := Node (Elmt);
15844 if not Is_Predefined_Dispatching_Operation (Subp)
15845 or else Comes_From_Source (Subp)
15847 Append_Elmt (Subp, Aux_List);
15853 Act_List := Aux_List;
15857 Act_Elmt := First_Elmt (Act_List);
15858 Act_Subp := Node (Act_Elmt);
15862 -- Stage 1: If the generic actual is not present we derive the
15863 -- primitives inherited from the parent type. If the generic parent
15864 -- type is present, the derived type is an instance of a formal
15865 -- derived type, and within the instance its operations are those of
15866 -- the actual. We derive from the formal type but make the inherited
15867 -- operations aliases of the corresponding operations of the actual.
15869 Elmt := First_Elmt (Op_List);
15870 while Present (Elmt) loop
15871 Subp := Node (Elmt);
15872 Alias_Subp := Ultimate_Alias (Subp);
15874 -- Do not derive internal entities of the parent that link
15875 -- interface primitives with their covering primitive. These
15876 -- entities will be added to this type when frozen.
15878 if Present (Interface_Alias (Subp)) then
15882 -- If the generic actual is present find the corresponding
15883 -- operation in the generic actual. If the parent type is a
15884 -- direct ancestor of the derived type then, even if it is an
15885 -- interface, the operations are inherited from the primary
15886 -- dispatch table and are in the proper order. If we detect here
15887 -- that primitives are not in the same order we traverse the list
15888 -- of primitive operations of the actual to find the one that
15889 -- implements the interface primitive.
15893 (Present (Generic_Actual)
15894 and then Present (Act_Subp)
15896 (Primitive_Names_Match (Subp, Act_Subp)
15898 Type_Conformant (Subp, Act_Subp,
15899 Skip_Controlling_Formals => True)))
15901 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15902 Use_Full_View => True));
15904 -- Remember that we need searching for all pending primitives
15906 Need_Search := True;
15908 -- Handle entities associated with interface primitives
15910 if Present (Alias_Subp)
15911 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15912 and then not Is_Predefined_Dispatching_Operation (Subp)
15914 -- Search for the primitive in the homonym chain
15917 Find_Primitive_Covering_Interface
15918 (Tagged_Type => Generic_Actual,
15919 Iface_Prim => Alias_Subp);
15921 -- Previous search may not locate primitives covering
15922 -- interfaces defined in generics units or instantiations.
15923 -- (it fails if the covering primitive has formals whose
15924 -- type is also defined in generics or instantiations).
15925 -- In such case we search in the list of primitives of the
15926 -- generic actual for the internal entity that links the
15927 -- interface primitive and the covering primitive.
15930 and then Is_Generic_Type (Parent_Type)
15932 -- This code has been designed to handle only generic
15933 -- formals that implement interfaces that are defined
15934 -- in a generic unit or instantiation. If this code is
15935 -- needed for other cases we must review it because
15936 -- (given that it relies on Original_Location to locate
15937 -- the primitive of Generic_Actual that covers the
15938 -- interface) it could leave linked through attribute
15939 -- Alias entities of unrelated instantiations).
15943 (Scope (Find_Dispatching_Type (Alias_Subp)))
15945 Instantiation_Depth
15946 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15949 Iface_Prim_Loc : constant Source_Ptr :=
15950 Original_Location (Sloc (Alias_Subp));
15957 First_Elmt (Primitive_Operations (Generic_Actual));
15959 Search : while Present (Elmt) loop
15960 Prim := Node (Elmt);
15962 if Present (Interface_Alias (Prim))
15963 and then Original_Location
15964 (Sloc (Interface_Alias (Prim))) =
15967 Act_Subp := Alias (Prim);
15976 pragma Assert (Present (Act_Subp)
15977 or else Is_Abstract_Type (Generic_Actual)
15978 or else Serious_Errors_Detected > 0);
15980 -- Handle predefined primitives plus the rest of user-defined
15984 Act_Elmt := First_Elmt (Act_List);
15985 while Present (Act_Elmt) loop
15986 Act_Subp := Node (Act_Elmt);
15988 exit when Primitive_Names_Match (Subp, Act_Subp)
15989 and then Type_Conformant
15991 Skip_Controlling_Formals => True)
15992 and then No (Interface_Alias (Act_Subp));
15994 Next_Elmt (Act_Elmt);
15997 if No (Act_Elmt) then
16003 -- Case 1: If the parent is a limited interface then it has the
16004 -- predefined primitives of synchronized interfaces. However, the
16005 -- actual type may be a non-limited type and hence it does not
16006 -- have such primitives.
16008 if Present (Generic_Actual)
16009 and then not Present (Act_Subp)
16010 and then Is_Limited_Interface (Parent_Base)
16011 and then Is_Predefined_Interface_Primitive (Subp)
16015 -- Case 2: Inherit entities associated with interfaces that were
16016 -- not covered by the parent type. We exclude here null interface
16017 -- primitives because they do not need special management.
16019 -- We also exclude interface operations that are renamings. If the
16020 -- subprogram is an explicit renaming of an interface primitive,
16021 -- it is a regular primitive operation, and the presence of its
16022 -- alias is not relevant: it has to be derived like any other
16025 elsif Present (Alias (Subp))
16026 and then Nkind (Unit_Declaration_Node (Subp)) /=
16027 N_Subprogram_Renaming_Declaration
16028 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
16030 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
16031 and then Null_Present (Parent (Alias_Subp)))
16033 -- If this is an abstract private type then we transfer the
16034 -- derivation of the interface primitive from the partial view
16035 -- to the full view. This is safe because all the interfaces
16036 -- must be visible in the partial view. Done to avoid adding
16037 -- a new interface derivation to the private part of the
16038 -- enclosing package; otherwise this new derivation would be
16039 -- decorated as hidden when the analysis of the enclosing
16040 -- package completes.
16042 if Is_Abstract_Type (Derived_Type)
16043 and then In_Private_Part (Current_Scope)
16044 and then Has_Private_Declaration (Derived_Type)
16047 Partial_View : Entity_Id;
16052 Partial_View := First_Entity (Current_Scope);
16054 exit when No (Partial_View)
16055 or else (Has_Private_Declaration (Partial_View)
16057 Full_View (Partial_View) = Derived_Type);
16059 Next_Entity (Partial_View);
16062 -- If the partial view was not found then the source code
16063 -- has errors and the derivation is not needed.
16065 if Present (Partial_View) then
16067 First_Elmt (Primitive_Operations (Partial_View));
16068 while Present (Elmt) loop
16069 Ent := Node (Elmt);
16071 if Present (Alias (Ent))
16072 and then Ultimate_Alias (Ent) = Alias (Subp)
16075 (Ent, Primitive_Operations (Derived_Type));
16082 -- If the interface primitive was not found in the
16083 -- partial view then this interface primitive was
16084 -- overridden. We add a derivation to activate in
16085 -- Derive_Progenitor_Subprograms the machinery to
16089 Derive_Interface_Subprogram
16090 (New_Subp => New_Subp,
16092 Actual_Subp => Act_Subp);
16097 Derive_Interface_Subprogram
16098 (New_Subp => New_Subp,
16100 Actual_Subp => Act_Subp);
16103 -- Case 3: Common derivation
16107 (New_Subp => New_Subp,
16108 Parent_Subp => Subp,
16109 Derived_Type => Derived_Type,
16110 Parent_Type => Parent_Base,
16111 Actual_Subp => Act_Subp);
16114 -- No need to update Act_Elm if we must search for the
16115 -- corresponding operation in the generic actual
16118 and then Present (Act_Elmt)
16120 Next_Elmt (Act_Elmt);
16121 Act_Subp := Node (Act_Elmt);
16128 -- Inherit additional operations from progenitors. If the derived
16129 -- type is a generic actual, there are not new primitive operations
16130 -- for the type because it has those of the actual, and therefore
16131 -- nothing needs to be done. The renamings generated above are not
16132 -- primitive operations, and their purpose is simply to make the
16133 -- proper operations visible within an instantiation.
16135 if No (Generic_Actual) then
16136 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
16140 -- Final check: Direct descendants must have their primitives in the
16141 -- same order. We exclude from this test untagged types and instances
16142 -- of formal derived types. We skip this test if we have already
16143 -- reported serious errors in the sources.
16145 pragma Assert (not Is_Tagged_Type (Derived_Type)
16146 or else Present (Generic_Actual)
16147 or else Serious_Errors_Detected > 0
16148 or else Check_Derived_Type);
16149 end Derive_Subprograms;
16151 --------------------------------
16152 -- Derived_Standard_Character --
16153 --------------------------------
16155 procedure Derived_Standard_Character
16157 Parent_Type : Entity_Id;
16158 Derived_Type : Entity_Id)
16160 Loc : constant Source_Ptr := Sloc (N);
16161 Def : constant Node_Id := Type_Definition (N);
16162 Indic : constant Node_Id := Subtype_Indication (Def);
16163 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
16164 Implicit_Base : constant Entity_Id :=
16166 (E_Enumeration_Type, N, Derived_Type, 'B');
16172 Discard_Node (Process_Subtype (Indic, N));
16174 Set_Etype (Implicit_Base, Parent_Base);
16175 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
16176 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
16178 Set_Is_Character_Type (Implicit_Base, True);
16179 Set_Has_Delayed_Freeze (Implicit_Base);
16181 -- The bounds of the implicit base are the bounds of the parent base.
16182 -- Note that their type is the parent base.
16184 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
16185 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
16187 Set_Scalar_Range (Implicit_Base,
16190 High_Bound => Hi));
16192 Conditional_Delay (Derived_Type, Parent_Type);
16194 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
16195 Set_Etype (Derived_Type, Implicit_Base);
16196 Set_Size_Info (Derived_Type, Parent_Type);
16198 if Unknown_RM_Size (Derived_Type) then
16199 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
16202 Set_Is_Character_Type (Derived_Type, True);
16204 if Nkind (Indic) /= N_Subtype_Indication then
16206 -- If no explicit constraint, the bounds are those
16207 -- of the parent type.
16209 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
16210 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
16211 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
16214 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
16216 -- Because the implicit base is used in the conversion of the bounds, we
16217 -- have to freeze it now. This is similar to what is done for numeric
16218 -- types, and it equally suspicious, but otherwise a non-static bound
16219 -- will have a reference to an unfrozen type, which is rejected by Gigi
16220 -- (???). This requires specific care for definition of stream
16221 -- attributes. For details, see comments at the end of
16222 -- Build_Derived_Numeric_Type.
16224 Freeze_Before (N, Implicit_Base);
16225 end Derived_Standard_Character;
16227 ------------------------------
16228 -- Derived_Type_Declaration --
16229 ------------------------------
16231 procedure Derived_Type_Declaration
16234 Is_Completion : Boolean)
16236 Parent_Type : Entity_Id;
16238 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
16239 -- Check whether the parent type is a generic formal, or derives
16240 -- directly or indirectly from one.
16242 ------------------------
16243 -- Comes_From_Generic --
16244 ------------------------
16246 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
16248 if Is_Generic_Type (Typ) then
16251 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
16254 elsif Is_Private_Type (Typ)
16255 and then Present (Full_View (Typ))
16256 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
16260 elsif Is_Generic_Actual_Type (Typ) then
16266 end Comes_From_Generic;
16270 Def : constant Node_Id := Type_Definition (N);
16271 Iface_Def : Node_Id;
16272 Indic : constant Node_Id := Subtype_Indication (Def);
16273 Extension : constant Node_Id := Record_Extension_Part (Def);
16274 Parent_Node : Node_Id;
16277 -- Start of processing for Derived_Type_Declaration
16280 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
16282 -- Ada 2005 (AI-251): In case of interface derivation check that the
16283 -- parent is also an interface.
16285 if Interface_Present (Def) then
16286 Check_SPARK_05_Restriction ("interface is not allowed", Def);
16288 if not Is_Interface (Parent_Type) then
16289 Diagnose_Interface (Indic, Parent_Type);
16292 Parent_Node := Parent (Base_Type (Parent_Type));
16293 Iface_Def := Type_Definition (Parent_Node);
16295 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
16296 -- other limited interfaces.
16298 if Limited_Present (Def) then
16299 if Limited_Present (Iface_Def) then
16302 elsif Protected_Present (Iface_Def) then
16304 ("descendant of & must be declared as a protected "
16305 & "interface", N, Parent_Type);
16307 elsif Synchronized_Present (Iface_Def) then
16309 ("descendant of & must be declared as a synchronized "
16310 & "interface", N, Parent_Type);
16312 elsif Task_Present (Iface_Def) then
16314 ("descendant of & must be declared as a task interface",
16319 ("(Ada 2005) limited interface cannot inherit from "
16320 & "non-limited interface", Indic);
16323 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
16324 -- from non-limited or limited interfaces.
16326 elsif not Protected_Present (Def)
16327 and then not Synchronized_Present (Def)
16328 and then not Task_Present (Def)
16330 if Limited_Present (Iface_Def) then
16333 elsif Protected_Present (Iface_Def) then
16335 ("descendant of & must be declared as a protected "
16336 & "interface", N, Parent_Type);
16338 elsif Synchronized_Present (Iface_Def) then
16340 ("descendant of & must be declared as a synchronized "
16341 & "interface", N, Parent_Type);
16343 elsif Task_Present (Iface_Def) then
16345 ("descendant of & must be declared as a task interface",
16354 if Is_Tagged_Type (Parent_Type)
16355 and then Is_Concurrent_Type (Parent_Type)
16356 and then not Is_Interface (Parent_Type)
16359 ("parent type of a record extension cannot be a synchronized "
16360 & "tagged type (RM 3.9.1 (3/1))", N);
16361 Set_Etype (T, Any_Type);
16365 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
16368 if Is_Tagged_Type (Parent_Type)
16369 and then Is_Non_Empty_List (Interface_List (Def))
16376 Intf := First (Interface_List (Def));
16377 while Present (Intf) loop
16378 T := Find_Type_Of_Subtype_Indic (Intf);
16380 if not Is_Interface (T) then
16381 Diagnose_Interface (Intf, T);
16383 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
16384 -- a limited type from having a nonlimited progenitor.
16386 elsif (Limited_Present (Def)
16387 or else (not Is_Interface (Parent_Type)
16388 and then Is_Limited_Type (Parent_Type)))
16389 and then not Is_Limited_Interface (T)
16392 ("progenitor interface& of limited type must be limited",
16401 if Parent_Type = Any_Type
16402 or else Etype (Parent_Type) = Any_Type
16403 or else (Is_Class_Wide_Type (Parent_Type)
16404 and then Etype (Parent_Type) = T)
16406 -- If Parent_Type is undefined or illegal, make new type into a
16407 -- subtype of Any_Type, and set a few attributes to prevent cascaded
16408 -- errors. If this is a self-definition, emit error now.
16410 if T = Parent_Type or else T = Etype (Parent_Type) then
16411 Error_Msg_N ("type cannot be used in its own definition", Indic);
16414 Set_Ekind (T, Ekind (Parent_Type));
16415 Set_Etype (T, Any_Type);
16416 Set_Scalar_Range (T, Scalar_Range (Any_Type));
16418 if Is_Tagged_Type (T)
16419 and then Is_Record_Type (T)
16421 Set_Direct_Primitive_Operations (T, New_Elmt_List);
16427 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
16428 -- an interface is special because the list of interfaces in the full
16429 -- view can be given in any order. For example:
16431 -- type A is interface;
16432 -- type B is interface and A;
16433 -- type D is new B with private;
16435 -- type D is new A and B with null record; -- 1 --
16437 -- In this case we perform the following transformation of -1-:
16439 -- type D is new B and A with null record;
16441 -- If the parent of the full-view covers the parent of the partial-view
16442 -- we have two possible cases:
16444 -- 1) They have the same parent
16445 -- 2) The parent of the full-view implements some further interfaces
16447 -- In both cases we do not need to perform the transformation. In the
16448 -- first case the source program is correct and the transformation is
16449 -- not needed; in the second case the source program does not fulfill
16450 -- the no-hidden interfaces rule (AI-396) and the error will be reported
16453 -- This transformation not only simplifies the rest of the analysis of
16454 -- this type declaration but also simplifies the correct generation of
16455 -- the object layout to the expander.
16457 if In_Private_Part (Current_Scope)
16458 and then Is_Interface (Parent_Type)
16462 Partial_View : Entity_Id;
16463 Partial_View_Parent : Entity_Id;
16464 New_Iface : Node_Id;
16467 -- Look for the associated private type declaration
16469 Partial_View := First_Entity (Current_Scope);
16471 exit when No (Partial_View)
16472 or else (Has_Private_Declaration (Partial_View)
16473 and then Full_View (Partial_View) = T);
16475 Next_Entity (Partial_View);
16478 -- If the partial view was not found then the source code has
16479 -- errors and the transformation is not needed.
16481 if Present (Partial_View) then
16482 Partial_View_Parent := Etype (Partial_View);
16484 -- If the parent of the full-view covers the parent of the
16485 -- partial-view we have nothing else to do.
16487 if Interface_Present_In_Ancestor
16488 (Parent_Type, Partial_View_Parent)
16492 -- Traverse the list of interfaces of the full-view to look
16493 -- for the parent of the partial-view and perform the tree
16497 Iface := First (Interface_List (Def));
16498 while Present (Iface) loop
16499 if Etype (Iface) = Etype (Partial_View) then
16500 Rewrite (Subtype_Indication (Def),
16501 New_Copy (Subtype_Indication
16502 (Parent (Partial_View))));
16505 Make_Identifier (Sloc (N), Chars (Parent_Type));
16506 Append (New_Iface, Interface_List (Def));
16508 -- Analyze the transformed code
16510 Derived_Type_Declaration (T, N, Is_Completion);
16521 -- Only composite types other than array types are allowed to have
16524 if Present (Discriminant_Specifications (N)) then
16525 if (Is_Elementary_Type (Parent_Type)
16527 Is_Array_Type (Parent_Type))
16528 and then not Error_Posted (N)
16531 ("elementary or array type cannot have discriminants",
16532 Defining_Identifier (First (Discriminant_Specifications (N))));
16533 Set_Has_Discriminants (T, False);
16535 -- The type is allowed to have discriminants
16538 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16542 -- In Ada 83, a derived type defined in a package specification cannot
16543 -- be used for further derivation until the end of its visible part.
16544 -- Note that derivation in the private part of the package is allowed.
16546 if Ada_Version = Ada_83
16547 and then Is_Derived_Type (Parent_Type)
16548 and then In_Visible_Part (Scope (Parent_Type))
16550 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16552 ("(Ada 83): premature use of type for derivation", Indic);
16556 -- Check for early use of incomplete or private type
16558 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16559 Error_Msg_N ("premature derivation of incomplete type", Indic);
16562 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16563 and then not Comes_From_Generic (Parent_Type))
16564 or else Has_Private_Component (Parent_Type)
16566 -- The ancestor type of a formal type can be incomplete, in which
16567 -- case only the operations of the partial view are available in the
16568 -- generic. Subsequent checks may be required when the full view is
16569 -- analyzed to verify that a derivation from a tagged type has an
16572 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16575 elsif No (Underlying_Type (Parent_Type))
16576 or else Has_Private_Component (Parent_Type)
16579 ("premature derivation of derived or private type", Indic);
16581 -- Flag the type itself as being in error, this prevents some
16582 -- nasty problems with subsequent uses of the malformed type.
16584 Set_Error_Posted (T);
16586 -- Check that within the immediate scope of an untagged partial
16587 -- view it's illegal to derive from the partial view if the
16588 -- full view is tagged. (7.3(7))
16590 -- We verify that the Parent_Type is a partial view by checking
16591 -- that it is not a Full_Type_Declaration (i.e. a private type or
16592 -- private extension declaration), to distinguish a partial view
16593 -- from a derivation from a private type which also appears as
16594 -- E_Private_Type. If the parent base type is not declared in an
16595 -- enclosing scope there is no need to check.
16597 elsif Present (Full_View (Parent_Type))
16598 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16599 and then not Is_Tagged_Type (Parent_Type)
16600 and then Is_Tagged_Type (Full_View (Parent_Type))
16601 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16604 ("premature derivation from type with tagged full view",
16609 -- Check that form of derivation is appropriate
16611 Taggd := Is_Tagged_Type (Parent_Type);
16613 -- Set the parent type to the class-wide type's specific type in this
16614 -- case to prevent cascading errors
16616 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16617 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16618 Set_Etype (T, Etype (Parent_Type));
16622 if Present (Extension) and then not Taggd then
16624 ("type derived from untagged type cannot have extension", Indic);
16626 elsif No (Extension) and then Taggd then
16628 -- If this declaration is within a private part (or body) of a
16629 -- generic instantiation then the derivation is allowed (the parent
16630 -- type can only appear tagged in this case if it's a generic actual
16631 -- type, since it would otherwise have been rejected in the analysis
16632 -- of the generic template).
16634 if not Is_Generic_Actual_Type (Parent_Type)
16635 or else In_Visible_Part (Scope (Parent_Type))
16637 if Is_Class_Wide_Type (Parent_Type) then
16639 ("parent type must not be a class-wide type", Indic);
16641 -- Use specific type to prevent cascaded errors.
16643 Parent_Type := Etype (Parent_Type);
16647 ("type derived from tagged type must have extension", Indic);
16652 -- AI-443: Synchronized formal derived types require a private
16653 -- extension. There is no point in checking the ancestor type or
16654 -- the progenitors since the construct is wrong to begin with.
16656 if Ada_Version >= Ada_2005
16657 and then Is_Generic_Type (T)
16658 and then Present (Original_Node (N))
16661 Decl : constant Node_Id := Original_Node (N);
16664 if Nkind (Decl) = N_Formal_Type_Declaration
16665 and then Nkind (Formal_Type_Definition (Decl)) =
16666 N_Formal_Derived_Type_Definition
16667 and then Synchronized_Present (Formal_Type_Definition (Decl))
16668 and then No (Extension)
16670 -- Avoid emitting a duplicate error message
16672 and then not Error_Posted (Indic)
16675 ("synchronized derived type must have extension", N);
16680 if Null_Exclusion_Present (Def)
16681 and then not Is_Access_Type (Parent_Type)
16683 Error_Msg_N ("null exclusion can only apply to an access type", N);
16686 -- Avoid deriving parent primitives of underlying record views
16688 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16689 Derive_Subps => not Is_Underlying_Record_View (T));
16691 -- AI-419: The parent type of an explicitly limited derived type must
16692 -- be a limited type or a limited interface.
16694 if Limited_Present (Def) then
16695 Set_Is_Limited_Record (T);
16697 if Is_Interface (T) then
16698 Set_Is_Limited_Interface (T);
16701 if not Is_Limited_Type (Parent_Type)
16703 (not Is_Interface (Parent_Type)
16704 or else not Is_Limited_Interface (Parent_Type))
16706 -- AI05-0096: a derivation in the private part of an instance is
16707 -- legal if the generic formal is untagged limited, and the actual
16710 if Is_Generic_Actual_Type (Parent_Type)
16711 and then In_Private_Part (Current_Scope)
16714 (Generic_Parent_Type (Parent (Parent_Type)))
16720 ("parent type& of limited type must be limited",
16726 -- In SPARK, there are no derived type definitions other than type
16727 -- extensions of tagged record types.
16729 if No (Extension) then
16730 Check_SPARK_05_Restriction
16731 ("derived type is not allowed", Original_Node (N));
16733 end Derived_Type_Declaration;
16735 ------------------------
16736 -- Diagnose_Interface --
16737 ------------------------
16739 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16741 if not Is_Interface (E) and then E /= Any_Type then
16742 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16744 end Diagnose_Interface;
16746 ----------------------------------
16747 -- Enumeration_Type_Declaration --
16748 ----------------------------------
16750 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16757 -- Create identifier node representing lower bound
16759 B_Node := New_Node (N_Identifier, Sloc (Def));
16760 L := First (Literals (Def));
16761 Set_Chars (B_Node, Chars (L));
16762 Set_Entity (B_Node, L);
16763 Set_Etype (B_Node, T);
16764 Set_Is_Static_Expression (B_Node, True);
16766 R_Node := New_Node (N_Range, Sloc (Def));
16767 Set_Low_Bound (R_Node, B_Node);
16769 Set_Ekind (T, E_Enumeration_Type);
16770 Set_First_Literal (T, L);
16772 Set_Is_Constrained (T);
16776 -- Loop through literals of enumeration type setting pos and rep values
16777 -- except that if the Ekind is already set, then it means the literal
16778 -- was already constructed (case of a derived type declaration and we
16779 -- should not disturb the Pos and Rep values.
16781 while Present (L) loop
16782 if Ekind (L) /= E_Enumeration_Literal then
16783 Set_Ekind (L, E_Enumeration_Literal);
16784 Set_Enumeration_Pos (L, Ev);
16785 Set_Enumeration_Rep (L, Ev);
16786 Set_Is_Known_Valid (L, True);
16790 New_Overloaded_Entity (L);
16791 Generate_Definition (L);
16792 Set_Convention (L, Convention_Intrinsic);
16794 -- Case of character literal
16796 if Nkind (L) = N_Defining_Character_Literal then
16797 Set_Is_Character_Type (T, True);
16799 -- Check violation of No_Wide_Characters
16801 if Restriction_Check_Required (No_Wide_Characters) then
16802 Get_Name_String (Chars (L));
16804 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16805 Check_Restriction (No_Wide_Characters, L);
16814 -- Now create a node representing upper bound
16816 B_Node := New_Node (N_Identifier, Sloc (Def));
16817 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16818 Set_Entity (B_Node, Last (Literals (Def)));
16819 Set_Etype (B_Node, T);
16820 Set_Is_Static_Expression (B_Node, True);
16822 Set_High_Bound (R_Node, B_Node);
16824 -- Initialize various fields of the type. Some of this information
16825 -- may be overwritten later through rep.clauses.
16827 Set_Scalar_Range (T, R_Node);
16828 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16829 Set_Enum_Esize (T);
16830 Set_Enum_Pos_To_Rep (T, Empty);
16832 -- Set Discard_Names if configuration pragma set, or if there is
16833 -- a parameterless pragma in the current declarative region
16835 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16836 Set_Discard_Names (T);
16839 -- Process end label if there is one
16841 if Present (Def) then
16842 Process_End_Label (Def, 'e', T);
16844 end Enumeration_Type_Declaration;
16846 ---------------------------------
16847 -- Expand_To_Stored_Constraint --
16848 ---------------------------------
16850 function Expand_To_Stored_Constraint
16852 Constraint : Elist_Id) return Elist_Id
16854 Explicitly_Discriminated_Type : Entity_Id;
16855 Expansion : Elist_Id;
16856 Discriminant : Entity_Id;
16858 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16859 -- Find the nearest type that actually specifies discriminants
16861 ---------------------------------
16862 -- Type_With_Explicit_Discrims --
16863 ---------------------------------
16865 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16866 Typ : constant E := Base_Type (Id);
16869 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16870 if Present (Full_View (Typ)) then
16871 return Type_With_Explicit_Discrims (Full_View (Typ));
16875 if Has_Discriminants (Typ) then
16880 if Etype (Typ) = Typ then
16882 elsif Has_Discriminants (Typ) then
16885 return Type_With_Explicit_Discrims (Etype (Typ));
16888 end Type_With_Explicit_Discrims;
16890 -- Start of processing for Expand_To_Stored_Constraint
16893 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16897 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16899 if No (Explicitly_Discriminated_Type) then
16903 Expansion := New_Elmt_List;
16906 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16907 while Present (Discriminant) loop
16909 (Get_Discriminant_Value
16910 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16912 Next_Stored_Discriminant (Discriminant);
16916 end Expand_To_Stored_Constraint;
16918 ---------------------------
16919 -- Find_Hidden_Interface --
16920 ---------------------------
16922 function Find_Hidden_Interface
16924 Dest : Elist_Id) return Entity_Id
16927 Iface_Elmt : Elmt_Id;
16930 if Present (Src) and then Present (Dest) then
16931 Iface_Elmt := First_Elmt (Src);
16932 while Present (Iface_Elmt) loop
16933 Iface := Node (Iface_Elmt);
16935 if Is_Interface (Iface)
16936 and then not Contain_Interface (Iface, Dest)
16941 Next_Elmt (Iface_Elmt);
16946 end Find_Hidden_Interface;
16948 --------------------
16949 -- Find_Type_Name --
16950 --------------------
16952 function Find_Type_Name (N : Node_Id) return Entity_Id is
16953 Id : constant Entity_Id := Defining_Identifier (N);
16954 New_Id : Entity_Id;
16956 Prev_Par : Node_Id;
16958 procedure Check_Duplicate_Aspects;
16959 -- Check that aspects specified in a completion have not been specified
16960 -- already in the partial view.
16962 procedure Tag_Mismatch;
16963 -- Diagnose a tagged partial view whose full view is untagged. We post
16964 -- the message on the full view, with a reference to the previous
16965 -- partial view. The partial view can be private or incomplete, and
16966 -- these are handled in a different manner, so we determine the position
16967 -- of the error message from the respective slocs of both.
16969 -----------------------------
16970 -- Check_Duplicate_Aspects --
16971 -----------------------------
16973 procedure Check_Duplicate_Aspects is
16974 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
16975 -- Return the corresponding aspect of the partial view which matches
16976 -- the aspect id of Asp. Return Empty is no such aspect exists.
16978 -----------------------------
16979 -- Get_Partial_View_Aspect --
16980 -----------------------------
16982 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
16983 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
16984 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
16985 Prev_Asp : Node_Id;
16988 if Present (Prev_Asps) then
16989 Prev_Asp := First (Prev_Asps);
16990 while Present (Prev_Asp) loop
16991 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
17000 end Get_Partial_View_Aspect;
17004 Full_Asps : constant List_Id := Aspect_Specifications (N);
17005 Full_Asp : Node_Id;
17006 Part_Asp : Node_Id;
17008 -- Start of processing for Check_Duplicate_Aspects
17011 if Present (Full_Asps) then
17012 Full_Asp := First (Full_Asps);
17013 while Present (Full_Asp) loop
17014 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
17016 -- An aspect and its class-wide counterpart are two distinct
17017 -- aspects and may apply to both views of an entity.
17019 if Present (Part_Asp)
17020 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
17023 ("aspect already specified in private declaration",
17030 if Has_Discriminants (Prev)
17031 and then not Has_Unknown_Discriminants (Prev)
17032 and then Get_Aspect_Id (Full_Asp) =
17033 Aspect_Implicit_Dereference
17036 ("cannot specify aspect if partial view has known "
17037 & "discriminants", Full_Asp);
17043 end Check_Duplicate_Aspects;
17049 procedure Tag_Mismatch is
17051 if Sloc (Prev) < Sloc (Id) then
17052 if Ada_Version >= Ada_2012
17053 and then Nkind (N) = N_Private_Type_Declaration
17056 ("declaration of private } must be a tagged type ", Id, Prev);
17059 ("full declaration of } must be a tagged type ", Id, Prev);
17063 if Ada_Version >= Ada_2012
17064 and then Nkind (N) = N_Private_Type_Declaration
17067 ("declaration of private } must be a tagged type ", Prev, Id);
17070 ("full declaration of } must be a tagged type ", Prev, Id);
17075 -- Start of processing for Find_Type_Name
17078 -- Find incomplete declaration, if one was given
17080 Prev := Current_Entity_In_Scope (Id);
17082 -- New type declaration
17088 -- Previous declaration exists
17091 Prev_Par := Parent (Prev);
17093 -- Error if not incomplete/private case except if previous
17094 -- declaration is implicit, etc. Enter_Name will emit error if
17097 if not Is_Incomplete_Or_Private_Type (Prev) then
17101 -- Check invalid completion of private or incomplete type
17103 elsif not Nkind_In (N, N_Full_Type_Declaration,
17104 N_Task_Type_Declaration,
17105 N_Protected_Type_Declaration)
17107 (Ada_Version < Ada_2012
17108 or else not Is_Incomplete_Type (Prev)
17109 or else not Nkind_In (N, N_Private_Type_Declaration,
17110 N_Private_Extension_Declaration))
17112 -- Completion must be a full type declarations (RM 7.3(4))
17114 Error_Msg_Sloc := Sloc (Prev);
17115 Error_Msg_NE ("invalid completion of }", Id, Prev);
17117 -- Set scope of Id to avoid cascaded errors. Entity is never
17118 -- examined again, except when saving globals in generics.
17120 Set_Scope (Id, Current_Scope);
17123 -- If this is a repeated incomplete declaration, no further
17124 -- checks are possible.
17126 if Nkind (N) = N_Incomplete_Type_Declaration then
17130 -- Case of full declaration of incomplete type
17132 elsif Ekind (Prev) = E_Incomplete_Type
17133 and then (Ada_Version < Ada_2012
17134 or else No (Full_View (Prev))
17135 or else not Is_Private_Type (Full_View (Prev)))
17137 -- Indicate that the incomplete declaration has a matching full
17138 -- declaration. The defining occurrence of the incomplete
17139 -- declaration remains the visible one, and the procedure
17140 -- Get_Full_View dereferences it whenever the type is used.
17142 if Present (Full_View (Prev)) then
17143 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
17146 Set_Full_View (Prev, Id);
17147 Append_Entity (Id, Current_Scope);
17148 Set_Is_Public (Id, Is_Public (Prev));
17149 Set_Is_Internal (Id);
17152 -- If the incomplete view is tagged, a class_wide type has been
17153 -- created already. Use it for the private type as well, in order
17154 -- to prevent multiple incompatible class-wide types that may be
17155 -- created for self-referential anonymous access components.
17157 if Is_Tagged_Type (Prev)
17158 and then Present (Class_Wide_Type (Prev))
17160 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
17161 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
17163 -- Type of the class-wide type is the current Id. Previously
17164 -- this was not done for private declarations because of order-
17165 -- of-elaboration issues in the back end, but gigi now handles
17168 Set_Etype (Class_Wide_Type (Id), Id);
17171 -- Case of full declaration of private type
17174 -- If the private type was a completion of an incomplete type then
17175 -- update Prev to reference the private type
17177 if Ada_Version >= Ada_2012
17178 and then Ekind (Prev) = E_Incomplete_Type
17179 and then Present (Full_View (Prev))
17180 and then Is_Private_Type (Full_View (Prev))
17182 Prev := Full_View (Prev);
17183 Prev_Par := Parent (Prev);
17186 if Nkind (N) = N_Full_Type_Declaration
17188 (Type_Definition (N), N_Record_Definition,
17189 N_Derived_Type_Definition)
17190 and then Interface_Present (Type_Definition (N))
17193 ("completion of private type cannot be an interface", N);
17196 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
17197 if Etype (Prev) /= Prev then
17199 -- Prev is a private subtype or a derived type, and needs
17202 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
17205 elsif Ekind (Prev) = E_Private_Type
17206 and then Nkind_In (N, N_Task_Type_Declaration,
17207 N_Protected_Type_Declaration)
17210 ("completion of nonlimited type cannot be limited", N);
17212 elsif Ekind (Prev) = E_Record_Type_With_Private
17213 and then Nkind_In (N, N_Task_Type_Declaration,
17214 N_Protected_Type_Declaration)
17216 if not Is_Limited_Record (Prev) then
17218 ("completion of nonlimited type cannot be limited", N);
17220 elsif No (Interface_List (N)) then
17222 ("completion of tagged private type must be tagged",
17227 -- Ada 2005 (AI-251): Private extension declaration of a task
17228 -- type or a protected type. This case arises when covering
17229 -- interface types.
17231 elsif Nkind_In (N, N_Task_Type_Declaration,
17232 N_Protected_Type_Declaration)
17236 elsif Nkind (N) /= N_Full_Type_Declaration
17237 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
17240 ("full view of private extension must be an extension", N);
17242 elsif not (Abstract_Present (Parent (Prev)))
17243 and then Abstract_Present (Type_Definition (N))
17246 ("full view of non-abstract extension cannot be abstract", N);
17249 if not In_Private_Part (Current_Scope) then
17251 ("declaration of full view must appear in private part", N);
17254 if Ada_Version >= Ada_2012 then
17255 Check_Duplicate_Aspects;
17258 Copy_And_Swap (Prev, Id);
17259 Set_Has_Private_Declaration (Prev);
17260 Set_Has_Private_Declaration (Id);
17262 -- AI12-0133: Indicate whether we have a partial view with
17263 -- unknown discriminants, in which case initialization of objects
17264 -- of the type do not receive an invariant check.
17266 Set_Partial_View_Has_Unknown_Discr
17267 (Prev, Has_Unknown_Discriminants (Id));
17269 -- Preserve aspect and iterator flags that may have been set on
17270 -- the partial view.
17272 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
17273 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
17275 -- If no error, propagate freeze_node from private to full view.
17276 -- It may have been generated for an early operational item.
17278 if Present (Freeze_Node (Id))
17279 and then Serious_Errors_Detected = 0
17280 and then No (Full_View (Id))
17282 Set_Freeze_Node (Prev, Freeze_Node (Id));
17283 Set_Freeze_Node (Id, Empty);
17284 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
17287 Set_Full_View (Id, Prev);
17291 -- Verify that full declaration conforms to partial one
17293 if Is_Incomplete_Or_Private_Type (Prev)
17294 and then Present (Discriminant_Specifications (Prev_Par))
17296 if Present (Discriminant_Specifications (N)) then
17297 if Ekind (Prev) = E_Incomplete_Type then
17298 Check_Discriminant_Conformance (N, Prev, Prev);
17300 Check_Discriminant_Conformance (N, Prev, Id);
17305 ("missing discriminants in full type declaration", N);
17307 -- To avoid cascaded errors on subsequent use, share the
17308 -- discriminants of the partial view.
17310 Set_Discriminant_Specifications (N,
17311 Discriminant_Specifications (Prev_Par));
17315 -- A prior untagged partial view can have an associated class-wide
17316 -- type due to use of the class attribute, and in this case the full
17317 -- type must also be tagged. This Ada 95 usage is deprecated in favor
17318 -- of incomplete tagged declarations, but we check for it.
17321 and then (Is_Tagged_Type (Prev)
17322 or else Present (Class_Wide_Type (Prev)))
17324 -- Ada 2012 (AI05-0162): A private type may be the completion of
17325 -- an incomplete type.
17327 if Ada_Version >= Ada_2012
17328 and then Is_Incomplete_Type (Prev)
17329 and then Nkind_In (N, N_Private_Type_Declaration,
17330 N_Private_Extension_Declaration)
17332 -- No need to check private extensions since they are tagged
17334 if Nkind (N) = N_Private_Type_Declaration
17335 and then not Tagged_Present (N)
17340 -- The full declaration is either a tagged type (including
17341 -- a synchronized type that implements interfaces) or a
17342 -- type extension, otherwise this is an error.
17344 elsif Nkind_In (N, N_Task_Type_Declaration,
17345 N_Protected_Type_Declaration)
17347 if No (Interface_List (N)) and then not Error_Posted (N) then
17351 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
17353 -- Indicate that the previous declaration (tagged incomplete
17354 -- or private declaration) requires the same on the full one.
17356 if not Tagged_Present (Type_Definition (N)) then
17358 Set_Is_Tagged_Type (Id);
17361 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
17362 if No (Record_Extension_Part (Type_Definition (N))) then
17364 ("full declaration of } must be a record extension",
17367 -- Set some attributes to produce a usable full view
17369 Set_Is_Tagged_Type (Id);
17378 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
17379 and then Present (Premature_Use (Parent (Prev)))
17381 Error_Msg_Sloc := Sloc (N);
17383 ("\full declaration #", Premature_Use (Parent (Prev)));
17388 end Find_Type_Name;
17390 -------------------------
17391 -- Find_Type_Of_Object --
17392 -------------------------
17394 function Find_Type_Of_Object
17395 (Obj_Def : Node_Id;
17396 Related_Nod : Node_Id) return Entity_Id
17398 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
17399 P : Node_Id := Parent (Obj_Def);
17404 -- If the parent is a component_definition node we climb to the
17405 -- component_declaration node
17407 if Nkind (P) = N_Component_Definition then
17411 -- Case of an anonymous array subtype
17413 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
17414 N_Unconstrained_Array_Definition)
17417 Array_Type_Declaration (T, Obj_Def);
17419 -- Create an explicit subtype whenever possible
17421 elsif Nkind (P) /= N_Component_Declaration
17422 and then Def_Kind = N_Subtype_Indication
17424 -- Base name of subtype on object name, which will be unique in
17425 -- the current scope.
17427 -- If this is a duplicate declaration, return base type, to avoid
17428 -- generating duplicate anonymous types.
17430 if Error_Posted (P) then
17431 Analyze (Subtype_Mark (Obj_Def));
17432 return Entity (Subtype_Mark (Obj_Def));
17437 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
17439 T := Make_Defining_Identifier (Sloc (P), Nam);
17441 Insert_Action (Obj_Def,
17442 Make_Subtype_Declaration (Sloc (P),
17443 Defining_Identifier => T,
17444 Subtype_Indication => Relocate_Node (Obj_Def)));
17446 -- This subtype may need freezing, and this will not be done
17447 -- automatically if the object declaration is not in declarative
17448 -- part. Since this is an object declaration, the type cannot always
17449 -- be frozen here. Deferred constants do not freeze their type
17450 -- (which often enough will be private).
17452 if Nkind (P) = N_Object_Declaration
17453 and then Constant_Present (P)
17454 and then No (Expression (P))
17458 -- Here we freeze the base type of object type to catch premature use
17459 -- of discriminated private type without a full view.
17462 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
17465 -- Ada 2005 AI-406: the object definition in an object declaration
17466 -- can be an access definition.
17468 elsif Def_Kind = N_Access_Definition then
17469 T := Access_Definition (Related_Nod, Obj_Def);
17471 Set_Is_Local_Anonymous_Access
17473 V => (Ada_Version < Ada_2012)
17474 or else (Nkind (P) /= N_Object_Declaration)
17475 or else Is_Library_Level_Entity (Defining_Identifier (P)));
17477 -- Otherwise, the object definition is just a subtype_mark
17480 T := Process_Subtype (Obj_Def, Related_Nod);
17482 -- If expansion is disabled an object definition that is an aggregate
17483 -- will not get expanded and may lead to scoping problems in the back
17484 -- end, if the object is referenced in an inner scope. In that case
17485 -- create an itype reference for the object definition now. This
17486 -- may be redundant in some cases, but harmless.
17489 and then Nkind (Related_Nod) = N_Object_Declaration
17492 Build_Itype_Reference (T, Related_Nod);
17497 end Find_Type_Of_Object;
17499 --------------------------------
17500 -- Find_Type_Of_Subtype_Indic --
17501 --------------------------------
17503 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
17507 -- Case of subtype mark with a constraint
17509 if Nkind (S) = N_Subtype_Indication then
17510 Find_Type (Subtype_Mark (S));
17511 Typ := Entity (Subtype_Mark (S));
17514 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17517 ("incorrect constraint for this kind of type", Constraint (S));
17518 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17521 -- Otherwise we have a subtype mark without a constraint
17523 elsif Error_Posted (S) then
17524 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17532 -- Check No_Wide_Characters restriction
17534 Check_Wide_Character_Restriction (Typ, S);
17537 end Find_Type_Of_Subtype_Indic;
17539 -------------------------------------
17540 -- Floating_Point_Type_Declaration --
17541 -------------------------------------
17543 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17544 Digs : constant Node_Id := Digits_Expression (Def);
17545 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17547 Base_Typ : Entity_Id;
17548 Implicit_Base : Entity_Id;
17551 function Can_Derive_From (E : Entity_Id) return Boolean;
17552 -- Find if given digits value, and possibly a specified range, allows
17553 -- derivation from specified type
17555 function Find_Base_Type return Entity_Id;
17556 -- Find a predefined base type that Def can derive from, or generate
17557 -- an error and substitute Long_Long_Float if none exists.
17559 ---------------------
17560 -- Can_Derive_From --
17561 ---------------------
17563 function Can_Derive_From (E : Entity_Id) return Boolean is
17564 Spec : constant Entity_Id := Real_Range_Specification (Def);
17567 -- Check specified "digits" constraint
17569 if Digs_Val > Digits_Value (E) then
17573 -- Check for matching range, if specified
17575 if Present (Spec) then
17576 if Expr_Value_R (Type_Low_Bound (E)) >
17577 Expr_Value_R (Low_Bound (Spec))
17582 if Expr_Value_R (Type_High_Bound (E)) <
17583 Expr_Value_R (High_Bound (Spec))
17590 end Can_Derive_From;
17592 --------------------
17593 -- Find_Base_Type --
17594 --------------------
17596 function Find_Base_Type return Entity_Id is
17597 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17600 -- Iterate over the predefined types in order, returning the first
17601 -- one that Def can derive from.
17603 while Present (Choice) loop
17604 if Can_Derive_From (Node (Choice)) then
17605 return Node (Choice);
17608 Next_Elmt (Choice);
17611 -- If we can't derive from any existing type, use Long_Long_Float
17612 -- and give appropriate message explaining the problem.
17614 if Digs_Val > Max_Digs_Val then
17615 -- It might be the case that there is a type with the requested
17616 -- range, just not the combination of digits and range.
17619 ("no predefined type has requested range and precision",
17620 Real_Range_Specification (Def));
17624 ("range too large for any predefined type",
17625 Real_Range_Specification (Def));
17628 return Standard_Long_Long_Float;
17629 end Find_Base_Type;
17631 -- Start of processing for Floating_Point_Type_Declaration
17634 Check_Restriction (No_Floating_Point, Def);
17636 -- Create an implicit base type
17639 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17641 -- Analyze and verify digits value
17643 Analyze_And_Resolve (Digs, Any_Integer);
17644 Check_Digits_Expression (Digs);
17645 Digs_Val := Expr_Value (Digs);
17647 -- Process possible range spec and find correct type to derive from
17649 Process_Real_Range_Specification (Def);
17651 -- Check that requested number of digits is not too high.
17653 if Digs_Val > Max_Digs_Val then
17655 -- The check for Max_Base_Digits may be somewhat expensive, as it
17656 -- requires reading System, so only do it when necessary.
17659 Max_Base_Digits : constant Uint :=
17662 (Parent (RTE (RE_Max_Base_Digits))));
17665 if Digs_Val > Max_Base_Digits then
17666 Error_Msg_Uint_1 := Max_Base_Digits;
17667 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17669 elsif No (Real_Range_Specification (Def)) then
17670 Error_Msg_Uint_1 := Max_Digs_Val;
17671 Error_Msg_N ("types with more than ^ digits need range spec "
17672 & "(RM 3.5.7(6))", Digs);
17677 -- Find a suitable type to derive from or complain and use a substitute
17679 Base_Typ := Find_Base_Type;
17681 -- If there are bounds given in the declaration use them as the bounds
17682 -- of the type, otherwise use the bounds of the predefined base type
17683 -- that was chosen based on the Digits value.
17685 if Present (Real_Range_Specification (Def)) then
17686 Set_Scalar_Range (T, Real_Range_Specification (Def));
17687 Set_Is_Constrained (T);
17689 -- The bounds of this range must be converted to machine numbers
17690 -- in accordance with RM 4.9(38).
17692 Bound := Type_Low_Bound (T);
17694 if Nkind (Bound) = N_Real_Literal then
17696 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17697 Set_Is_Machine_Number (Bound);
17700 Bound := Type_High_Bound (T);
17702 if Nkind (Bound) = N_Real_Literal then
17704 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17705 Set_Is_Machine_Number (Bound);
17709 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17712 -- Complete definition of implicit base and declared first subtype. The
17713 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17714 -- are not clobbered when the floating point type acts as a full view of
17717 Set_Etype (Implicit_Base, Base_Typ);
17718 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17719 Set_Size_Info (Implicit_Base, Base_Typ);
17720 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17721 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17722 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17723 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17725 Set_Ekind (T, E_Floating_Point_Subtype);
17726 Set_Etype (T, Implicit_Base);
17727 Set_Size_Info (T, Implicit_Base);
17728 Set_RM_Size (T, RM_Size (Implicit_Base));
17729 Inherit_Rep_Item_Chain (T, Implicit_Base);
17730 Set_Digits_Value (T, Digs_Val);
17731 end Floating_Point_Type_Declaration;
17733 ----------------------------
17734 -- Get_Discriminant_Value --
17735 ----------------------------
17737 -- This is the situation:
17739 -- There is a non-derived type
17741 -- type T0 (Dx, Dy, Dz...)
17743 -- There are zero or more levels of derivation, with each derivation
17744 -- either purely inheriting the discriminants, or defining its own.
17746 -- type Ti is new Ti-1
17748 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17750 -- subtype Ti is ...
17752 -- The subtype issue is avoided by the use of Original_Record_Component,
17753 -- and the fact that derived subtypes also derive the constraints.
17755 -- This chain leads back from
17757 -- Typ_For_Constraint
17759 -- Typ_For_Constraint has discriminants, and the value for each
17760 -- discriminant is given by its corresponding Elmt of Constraints.
17762 -- Discriminant is some discriminant in this hierarchy
17764 -- We need to return its value
17766 -- We do this by recursively searching each level, and looking for
17767 -- Discriminant. Once we get to the bottom, we start backing up
17768 -- returning the value for it which may in turn be a discriminant
17769 -- further up, so on the backup we continue the substitution.
17771 function Get_Discriminant_Value
17772 (Discriminant : Entity_Id;
17773 Typ_For_Constraint : Entity_Id;
17774 Constraint : Elist_Id) return Node_Id
17776 function Root_Corresponding_Discriminant
17777 (Discr : Entity_Id) return Entity_Id;
17778 -- Given a discriminant, traverse the chain of inherited discriminants
17779 -- and return the topmost discriminant.
17781 function Search_Derivation_Levels
17783 Discrim_Values : Elist_Id;
17784 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17785 -- This is the routine that performs the recursive search of levels
17786 -- as described above.
17788 -------------------------------------
17789 -- Root_Corresponding_Discriminant --
17790 -------------------------------------
17792 function Root_Corresponding_Discriminant
17793 (Discr : Entity_Id) return Entity_Id
17799 while Present (Corresponding_Discriminant (D)) loop
17800 D := Corresponding_Discriminant (D);
17804 end Root_Corresponding_Discriminant;
17806 ------------------------------
17807 -- Search_Derivation_Levels --
17808 ------------------------------
17810 function Search_Derivation_Levels
17812 Discrim_Values : Elist_Id;
17813 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17817 Result : Node_Or_Entity_Id;
17818 Result_Entity : Node_Id;
17821 -- If inappropriate type, return Error, this happens only in
17822 -- cascaded error situations, and we want to avoid a blow up.
17824 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17828 -- Look deeper if possible. Use Stored_Constraints only for
17829 -- untagged types. For tagged types use the given constraint.
17830 -- This asymmetry needs explanation???
17832 if not Stored_Discrim_Values
17833 and then Present (Stored_Constraint (Ti))
17834 and then not Is_Tagged_Type (Ti)
17837 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17840 Td : constant Entity_Id := Etype (Ti);
17844 Result := Discriminant;
17847 if Present (Stored_Constraint (Ti)) then
17849 Search_Derivation_Levels
17850 (Td, Stored_Constraint (Ti), True);
17853 Search_Derivation_Levels
17854 (Td, Discrim_Values, Stored_Discrim_Values);
17860 -- Extra underlying places to search, if not found above. For
17861 -- concurrent types, the relevant discriminant appears in the
17862 -- corresponding record. For a type derived from a private type
17863 -- without discriminant, the full view inherits the discriminants
17864 -- of the full view of the parent.
17866 if Result = Discriminant then
17867 if Is_Concurrent_Type (Ti)
17868 and then Present (Corresponding_Record_Type (Ti))
17871 Search_Derivation_Levels (
17872 Corresponding_Record_Type (Ti),
17874 Stored_Discrim_Values);
17876 elsif Is_Private_Type (Ti)
17877 and then not Has_Discriminants (Ti)
17878 and then Present (Full_View (Ti))
17879 and then Etype (Full_View (Ti)) /= Ti
17882 Search_Derivation_Levels (
17885 Stored_Discrim_Values);
17889 -- If Result is not a (reference to a) discriminant, return it,
17890 -- otherwise set Result_Entity to the discriminant.
17892 if Nkind (Result) = N_Defining_Identifier then
17893 pragma Assert (Result = Discriminant);
17894 Result_Entity := Result;
17897 if not Denotes_Discriminant (Result) then
17901 Result_Entity := Entity (Result);
17904 -- See if this level of derivation actually has discriminants because
17905 -- tagged derivations can add them, hence the lower levels need not
17908 if not Has_Discriminants (Ti) then
17912 -- Scan Ti's discriminants for Result_Entity, and return its
17913 -- corresponding value, if any.
17915 Result_Entity := Original_Record_Component (Result_Entity);
17917 Assoc := First_Elmt (Discrim_Values);
17919 if Stored_Discrim_Values then
17920 Disc := First_Stored_Discriminant (Ti);
17922 Disc := First_Discriminant (Ti);
17925 while Present (Disc) loop
17927 -- If no further associations return the discriminant, value will
17928 -- be found on the second pass.
17934 if Original_Record_Component (Disc) = Result_Entity then
17935 return Node (Assoc);
17940 if Stored_Discrim_Values then
17941 Next_Stored_Discriminant (Disc);
17943 Next_Discriminant (Disc);
17947 -- Could not find it
17950 end Search_Derivation_Levels;
17954 Result : Node_Or_Entity_Id;
17956 -- Start of processing for Get_Discriminant_Value
17959 -- ??? This routine is a gigantic mess and will be deleted. For the
17960 -- time being just test for the trivial case before calling recurse.
17962 -- We are now celebrating the 20th anniversary of this comment!
17964 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17970 D := First_Discriminant (Typ_For_Constraint);
17971 E := First_Elmt (Constraint);
17972 while Present (D) loop
17973 if Chars (D) = Chars (Discriminant) then
17977 Next_Discriminant (D);
17983 Result := Search_Derivation_Levels
17984 (Typ_For_Constraint, Constraint, False);
17986 -- ??? hack to disappear when this routine is gone
17988 if Nkind (Result) = N_Defining_Identifier then
17994 D := First_Discriminant (Typ_For_Constraint);
17995 E := First_Elmt (Constraint);
17996 while Present (D) loop
17997 if Root_Corresponding_Discriminant (D) = Discriminant then
18001 Next_Discriminant (D);
18007 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
18009 end Get_Discriminant_Value;
18011 --------------------------
18012 -- Has_Range_Constraint --
18013 --------------------------
18015 function Has_Range_Constraint (N : Node_Id) return Boolean is
18016 C : constant Node_Id := Constraint (N);
18019 if Nkind (C) = N_Range_Constraint then
18022 elsif Nkind (C) = N_Digits_Constraint then
18024 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
18025 or else Present (Range_Constraint (C));
18027 elsif Nkind (C) = N_Delta_Constraint then
18028 return Present (Range_Constraint (C));
18033 end Has_Range_Constraint;
18035 ------------------------
18036 -- Inherit_Components --
18037 ------------------------
18039 function Inherit_Components
18041 Parent_Base : Entity_Id;
18042 Derived_Base : Entity_Id;
18043 Is_Tagged : Boolean;
18044 Inherit_Discr : Boolean;
18045 Discs : Elist_Id) return Elist_Id
18047 Assoc_List : constant Elist_Id := New_Elmt_List;
18049 procedure Inherit_Component
18050 (Old_C : Entity_Id;
18051 Plain_Discrim : Boolean := False;
18052 Stored_Discrim : Boolean := False);
18053 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
18054 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
18055 -- True, Old_C is a stored discriminant. If they are both false then
18056 -- Old_C is a regular component.
18058 -----------------------
18059 -- Inherit_Component --
18060 -----------------------
18062 procedure Inherit_Component
18063 (Old_C : Entity_Id;
18064 Plain_Discrim : Boolean := False;
18065 Stored_Discrim : Boolean := False)
18067 procedure Set_Anonymous_Type (Id : Entity_Id);
18068 -- Id denotes the entity of an access discriminant or anonymous
18069 -- access component. Set the type of Id to either the same type of
18070 -- Old_C or create a new one depending on whether the parent and
18071 -- the child types are in the same scope.
18073 ------------------------
18074 -- Set_Anonymous_Type --
18075 ------------------------
18077 procedure Set_Anonymous_Type (Id : Entity_Id) is
18078 Old_Typ : constant Entity_Id := Etype (Old_C);
18081 if Scope (Parent_Base) = Scope (Derived_Base) then
18082 Set_Etype (Id, Old_Typ);
18084 -- The parent and the derived type are in two different scopes.
18085 -- Reuse the type of the original discriminant / component by
18086 -- copying it in order to preserve all attributes.
18090 Typ : constant Entity_Id := New_Copy (Old_Typ);
18093 Set_Etype (Id, Typ);
18095 -- Since we do not generate component declarations for
18096 -- inherited components, associate the itype with the
18099 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
18100 Set_Scope (Typ, Derived_Base);
18103 end Set_Anonymous_Type;
18105 -- Local variables and constants
18107 New_C : constant Entity_Id := New_Copy (Old_C);
18109 Corr_Discrim : Entity_Id;
18110 Discrim : Entity_Id;
18112 -- Start of processing for Inherit_Component
18115 pragma Assert (not Is_Tagged or not Stored_Discrim);
18117 Set_Parent (New_C, Parent (Old_C));
18119 -- Regular discriminants and components must be inserted in the scope
18120 -- of the Derived_Base. Do it here.
18122 if not Stored_Discrim then
18123 Enter_Name (New_C);
18126 -- For tagged types the Original_Record_Component must point to
18127 -- whatever this field was pointing to in the parent type. This has
18128 -- already been achieved by the call to New_Copy above.
18130 if not Is_Tagged then
18131 Set_Original_Record_Component (New_C, New_C);
18132 Set_Corresponding_Record_Component (New_C, Old_C);
18135 -- Set the proper type of an access discriminant
18137 if Ekind (New_C) = E_Discriminant
18138 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
18140 Set_Anonymous_Type (New_C);
18143 -- If we have inherited a component then see if its Etype contains
18144 -- references to Parent_Base discriminants. In this case, replace
18145 -- these references with the constraints given in Discs. We do not
18146 -- do this for the partial view of private types because this is
18147 -- not needed (only the components of the full view will be used
18148 -- for code generation) and cause problem. We also avoid this
18149 -- transformation in some error situations.
18151 if Ekind (New_C) = E_Component then
18153 -- Set the proper type of an anonymous access component
18155 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
18156 Set_Anonymous_Type (New_C);
18158 elsif (Is_Private_Type (Derived_Base)
18159 and then not Is_Generic_Type (Derived_Base))
18160 or else (Is_Empty_Elmt_List (Discs)
18161 and then not Expander_Active)
18163 Set_Etype (New_C, Etype (Old_C));
18166 -- The current component introduces a circularity of the
18169 -- limited with Pack_2;
18170 -- package Pack_1 is
18171 -- type T_1 is tagged record
18172 -- Comp : access Pack_2.T_2;
18178 -- package Pack_2 is
18179 -- type T_2 is new Pack_1.T_1 with ...;
18184 Constrain_Component_Type
18185 (Old_C, Derived_Base, N, Parent_Base, Discs));
18189 -- In derived tagged types it is illegal to reference a non
18190 -- discriminant component in the parent type. To catch this, mark
18191 -- these components with an Ekind of E_Void. This will be reset in
18192 -- Record_Type_Definition after processing the record extension of
18193 -- the derived type.
18195 -- If the declaration is a private extension, there is no further
18196 -- record extension to process, and the components retain their
18197 -- current kind, because they are visible at this point.
18199 if Is_Tagged and then Ekind (New_C) = E_Component
18200 and then Nkind (N) /= N_Private_Extension_Declaration
18202 Set_Ekind (New_C, E_Void);
18205 if Plain_Discrim then
18206 Set_Corresponding_Discriminant (New_C, Old_C);
18207 Build_Discriminal (New_C);
18209 -- If we are explicitly inheriting a stored discriminant it will be
18210 -- completely hidden.
18212 elsif Stored_Discrim then
18213 Set_Corresponding_Discriminant (New_C, Empty);
18214 Set_Discriminal (New_C, Empty);
18215 Set_Is_Completely_Hidden (New_C);
18217 -- Set the Original_Record_Component of each discriminant in the
18218 -- derived base to point to the corresponding stored that we just
18221 Discrim := First_Discriminant (Derived_Base);
18222 while Present (Discrim) loop
18223 Corr_Discrim := Corresponding_Discriminant (Discrim);
18225 -- Corr_Discrim could be missing in an error situation
18227 if Present (Corr_Discrim)
18228 and then Original_Record_Component (Corr_Discrim) = Old_C
18230 Set_Original_Record_Component (Discrim, New_C);
18231 Set_Corresponding_Record_Component (Discrim, Empty);
18234 Next_Discriminant (Discrim);
18237 Append_Entity (New_C, Derived_Base);
18240 if not Is_Tagged then
18241 Append_Elmt (Old_C, Assoc_List);
18242 Append_Elmt (New_C, Assoc_List);
18244 end Inherit_Component;
18246 -- Variables local to Inherit_Component
18248 Loc : constant Source_Ptr := Sloc (N);
18250 Parent_Discrim : Entity_Id;
18251 Stored_Discrim : Entity_Id;
18253 Component : Entity_Id;
18255 -- Start of processing for Inherit_Components
18258 if not Is_Tagged then
18259 Append_Elmt (Parent_Base, Assoc_List);
18260 Append_Elmt (Derived_Base, Assoc_List);
18263 -- Inherit parent discriminants if needed
18265 if Inherit_Discr then
18266 Parent_Discrim := First_Discriminant (Parent_Base);
18267 while Present (Parent_Discrim) loop
18268 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
18269 Next_Discriminant (Parent_Discrim);
18273 -- Create explicit stored discrims for untagged types when necessary
18275 if not Has_Unknown_Discriminants (Derived_Base)
18276 and then Has_Discriminants (Parent_Base)
18277 and then not Is_Tagged
18280 or else First_Discriminant (Parent_Base) /=
18281 First_Stored_Discriminant (Parent_Base))
18283 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
18284 while Present (Stored_Discrim) loop
18285 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
18286 Next_Stored_Discriminant (Stored_Discrim);
18290 -- See if we can apply the second transformation for derived types, as
18291 -- explained in point 6. in the comments above Build_Derived_Record_Type
18292 -- This is achieved by appending Derived_Base discriminants into Discs,
18293 -- which has the side effect of returning a non empty Discs list to the
18294 -- caller of Inherit_Components, which is what we want. This must be
18295 -- done for private derived types if there are explicit stored
18296 -- discriminants, to ensure that we can retrieve the values of the
18297 -- constraints provided in the ancestors.
18300 and then Is_Empty_Elmt_List (Discs)
18301 and then Present (First_Discriminant (Derived_Base))
18303 (not Is_Private_Type (Derived_Base)
18304 or else Is_Completely_Hidden
18305 (First_Stored_Discriminant (Derived_Base))
18306 or else Is_Generic_Type (Derived_Base))
18308 D := First_Discriminant (Derived_Base);
18309 while Present (D) loop
18310 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
18311 Next_Discriminant (D);
18315 -- Finally, inherit non-discriminant components unless they are not
18316 -- visible because defined or inherited from the full view of the
18317 -- parent. Don't inherit the _parent field of the parent type.
18319 Component := First_Entity (Parent_Base);
18320 while Present (Component) loop
18322 -- Ada 2005 (AI-251): Do not inherit components associated with
18323 -- secondary tags of the parent.
18325 if Ekind (Component) = E_Component
18326 and then Present (Related_Type (Component))
18330 elsif Ekind (Component) /= E_Component
18331 or else Chars (Component) = Name_uParent
18335 -- If the derived type is within the parent type's declarative
18336 -- region, then the components can still be inherited even though
18337 -- they aren't visible at this point. This can occur for cases
18338 -- such as within public child units where the components must
18339 -- become visible upon entering the child unit's private part.
18341 elsif not Is_Visible_Component (Component)
18342 and then not In_Open_Scopes (Scope (Parent_Base))
18346 elsif Ekind_In (Derived_Base, E_Private_Type,
18347 E_Limited_Private_Type)
18352 Inherit_Component (Component);
18355 Next_Entity (Component);
18358 -- For tagged derived types, inherited discriminants cannot be used in
18359 -- component declarations of the record extension part. To achieve this
18360 -- we mark the inherited discriminants as not visible.
18362 if Is_Tagged and then Inherit_Discr then
18363 D := First_Discriminant (Derived_Base);
18364 while Present (D) loop
18365 Set_Is_Immediately_Visible (D, False);
18366 Next_Discriminant (D);
18371 end Inherit_Components;
18373 -----------------------------
18374 -- Inherit_Predicate_Flags --
18375 -----------------------------
18377 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
18379 Set_Has_Predicates (Subt, Has_Predicates (Par));
18380 Set_Has_Static_Predicate_Aspect
18381 (Subt, Has_Static_Predicate_Aspect (Par));
18382 Set_Has_Dynamic_Predicate_Aspect
18383 (Subt, Has_Dynamic_Predicate_Aspect (Par));
18384 end Inherit_Predicate_Flags;
18386 ----------------------
18387 -- Is_EVF_Procedure --
18388 ----------------------
18390 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
18391 Formal : Entity_Id;
18394 -- Examine the formals of an Extensions_Visible False procedure looking
18395 -- for a controlling OUT parameter.
18397 if Ekind (Subp) = E_Procedure
18398 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
18400 Formal := First_Formal (Subp);
18401 while Present (Formal) loop
18402 if Ekind (Formal) = E_Out_Parameter
18403 and then Is_Controlling_Formal (Formal)
18408 Next_Formal (Formal);
18413 end Is_EVF_Procedure;
18415 -----------------------
18416 -- Is_Null_Extension --
18417 -----------------------
18419 function Is_Null_Extension (T : Entity_Id) return Boolean is
18420 Type_Decl : constant Node_Id := Parent (Base_Type (T));
18421 Comp_List : Node_Id;
18425 if Nkind (Type_Decl) /= N_Full_Type_Declaration
18426 or else not Is_Tagged_Type (T)
18427 or else Nkind (Type_Definition (Type_Decl)) /=
18428 N_Derived_Type_Definition
18429 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
18435 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
18437 if Present (Discriminant_Specifications (Type_Decl)) then
18440 elsif Present (Comp_List)
18441 and then Is_Non_Empty_List (Component_Items (Comp_List))
18443 Comp := First (Component_Items (Comp_List));
18445 -- Only user-defined components are relevant. The component list
18446 -- may also contain a parent component and internal components
18447 -- corresponding to secondary tags, but these do not determine
18448 -- whether this is a null extension.
18450 while Present (Comp) loop
18451 if Comes_From_Source (Comp) then
18463 end Is_Null_Extension;
18465 ------------------------------
18466 -- Is_Valid_Constraint_Kind --
18467 ------------------------------
18469 function Is_Valid_Constraint_Kind
18470 (T_Kind : Type_Kind;
18471 Constraint_Kind : Node_Kind) return Boolean
18475 when Enumeration_Kind
18478 return Constraint_Kind = N_Range_Constraint;
18480 when Decimal_Fixed_Point_Kind =>
18481 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18482 N_Range_Constraint);
18484 when Ordinary_Fixed_Point_Kind =>
18485 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
18486 N_Range_Constraint);
18489 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18490 N_Range_Constraint);
18497 | E_Incomplete_Type
18501 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
18504 return True; -- Error will be detected later
18506 end Is_Valid_Constraint_Kind;
18508 --------------------------
18509 -- Is_Visible_Component --
18510 --------------------------
18512 function Is_Visible_Component
18514 N : Node_Id := Empty) return Boolean
18516 Original_Comp : Entity_Id := Empty;
18517 Original_Type : Entity_Id;
18518 Type_Scope : Entity_Id;
18520 function Is_Local_Type (Typ : Entity_Id) return Boolean;
18521 -- Check whether parent type of inherited component is declared locally,
18522 -- possibly within a nested package or instance. The current scope is
18523 -- the derived record itself.
18525 -------------------
18526 -- Is_Local_Type --
18527 -------------------
18529 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18533 Scop := Scope (Typ);
18534 while Present (Scop)
18535 and then Scop /= Standard_Standard
18537 if Scop = Scope (Current_Scope) then
18541 Scop := Scope (Scop);
18547 -- Start of processing for Is_Visible_Component
18550 if Ekind_In (C, E_Component, E_Discriminant) then
18551 Original_Comp := Original_Record_Component (C);
18554 if No (Original_Comp) then
18556 -- Premature usage, or previous error
18561 Original_Type := Scope (Original_Comp);
18562 Type_Scope := Scope (Base_Type (Scope (C)));
18565 -- This test only concerns tagged types
18567 if not Is_Tagged_Type (Original_Type) then
18570 -- If it is _Parent or _Tag, there is no visibility issue
18572 elsif not Comes_From_Source (Original_Comp) then
18575 -- Discriminants are visible unless the (private) type has unknown
18576 -- discriminants. If the discriminant reference is inserted for a
18577 -- discriminant check on a full view it is also visible.
18579 elsif Ekind (Original_Comp) = E_Discriminant
18581 (not Has_Unknown_Discriminants (Original_Type)
18582 or else (Present (N)
18583 and then Nkind (N) = N_Selected_Component
18584 and then Nkind (Prefix (N)) = N_Type_Conversion
18585 and then not Comes_From_Source (Prefix (N))))
18589 -- In the body of an instantiation, check the visibility of a component
18590 -- in case it has a homograph that is a primitive operation of a private
18591 -- type which was not visible in the generic unit.
18593 -- Should Is_Prefixed_Call be propagated from template to instance???
18595 elsif In_Instance_Body then
18596 if not Is_Tagged_Type (Original_Type)
18597 or else not Is_Private_Type (Original_Type)
18603 Subp_Elmt : Elmt_Id;
18606 Subp_Elmt := First_Elmt (Primitive_Operations (Original_Type));
18607 while Present (Subp_Elmt) loop
18609 -- The component is hidden by a primitive operation
18611 if Chars (Node (Subp_Elmt)) = Chars (C) then
18615 Next_Elmt (Subp_Elmt);
18622 -- If the component has been declared in an ancestor which is currently
18623 -- a private type, then it is not visible. The same applies if the
18624 -- component's containing type is not in an open scope and the original
18625 -- component's enclosing type is a visible full view of a private type
18626 -- (which can occur in cases where an attempt is being made to reference
18627 -- a component in a sibling package that is inherited from a visible
18628 -- component of a type in an ancestor package; the component in the
18629 -- sibling package should not be visible even though the component it
18630 -- inherited from is visible). This does not apply however in the case
18631 -- where the scope of the type is a private child unit, or when the
18632 -- parent comes from a local package in which the ancestor is currently
18633 -- visible. The latter suppression of visibility is needed for cases
18634 -- that are tested in B730006.
18636 elsif Is_Private_Type (Original_Type)
18638 (not Is_Private_Descendant (Type_Scope)
18639 and then not In_Open_Scopes (Type_Scope)
18640 and then Has_Private_Declaration (Original_Type))
18642 -- If the type derives from an entity in a formal package, there
18643 -- are no additional visible components.
18645 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18646 N_Formal_Package_Declaration
18650 -- if we are not in the private part of the current package, there
18651 -- are no additional visible components.
18653 elsif Ekind (Scope (Current_Scope)) = E_Package
18654 and then not In_Private_Part (Scope (Current_Scope))
18659 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18660 and then In_Open_Scopes (Scope (Original_Type))
18661 and then Is_Local_Type (Type_Scope);
18664 -- There is another weird way in which a component may be invisible when
18665 -- the private and the full view are not derived from the same ancestor.
18666 -- Here is an example :
18668 -- type A1 is tagged record F1 : integer; end record;
18669 -- type A2 is new A1 with record F2 : integer; end record;
18670 -- type T is new A1 with private;
18672 -- type T is new A2 with null record;
18674 -- In this case, the full view of T inherits F1 and F2 but the private
18675 -- view inherits only F1
18679 Ancestor : Entity_Id := Scope (C);
18683 if Ancestor = Original_Type then
18686 -- The ancestor may have a partial view of the original type,
18687 -- but if the full view is in scope, as in a child body, the
18688 -- component is visible.
18690 elsif In_Private_Part (Scope (Original_Type))
18691 and then Full_View (Ancestor) = Original_Type
18695 elsif Ancestor = Etype (Ancestor) then
18697 -- No further ancestors to examine
18702 Ancestor := Etype (Ancestor);
18706 end Is_Visible_Component;
18708 --------------------------
18709 -- Make_Class_Wide_Type --
18710 --------------------------
18712 procedure Make_Class_Wide_Type (T : Entity_Id) is
18713 CW_Type : Entity_Id;
18715 Next_E : Entity_Id;
18718 if Present (Class_Wide_Type (T)) then
18720 -- The class-wide type is a partially decorated entity created for a
18721 -- unanalyzed tagged type referenced through a limited with clause.
18722 -- When the tagged type is analyzed, its class-wide type needs to be
18723 -- redecorated. Note that we reuse the entity created by Decorate_
18724 -- Tagged_Type in order to preserve all links.
18726 if Materialize_Entity (Class_Wide_Type (T)) then
18727 CW_Type := Class_Wide_Type (T);
18728 Set_Materialize_Entity (CW_Type, False);
18730 -- The class wide type can have been defined by the partial view, in
18731 -- which case everything is already done.
18737 -- Default case, we need to create a new class-wide type
18741 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18744 -- Inherit root type characteristics
18746 CW_Name := Chars (CW_Type);
18747 Next_E := Next_Entity (CW_Type);
18748 Copy_Node (T, CW_Type);
18749 Set_Comes_From_Source (CW_Type, False);
18750 Set_Chars (CW_Type, CW_Name);
18751 Set_Parent (CW_Type, Parent (T));
18752 Set_Next_Entity (CW_Type, Next_E);
18754 -- Ensure we have a new freeze node for the class-wide type. The partial
18755 -- view may have freeze action of its own, requiring a proper freeze
18756 -- node, and the same freeze node cannot be shared between the two
18759 Set_Has_Delayed_Freeze (CW_Type);
18760 Set_Freeze_Node (CW_Type, Empty);
18762 -- Customize the class-wide type: It has no prim. op., it cannot be
18763 -- abstract, its Etype points back to the specific root type, and it
18764 -- cannot have any invariants.
18766 Set_Ekind (CW_Type, E_Class_Wide_Type);
18767 Set_Is_Tagged_Type (CW_Type, True);
18768 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18769 Set_Is_Abstract_Type (CW_Type, False);
18770 Set_Is_Constrained (CW_Type, False);
18771 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18772 Set_Default_SSO (CW_Type);
18773 Set_Has_Inheritable_Invariants (CW_Type, False);
18774 Set_Has_Inherited_Invariants (CW_Type, False);
18775 Set_Has_Own_Invariants (CW_Type, False);
18777 if Ekind (T) = E_Class_Wide_Subtype then
18778 Set_Etype (CW_Type, Etype (Base_Type (T)));
18780 Set_Etype (CW_Type, T);
18783 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18785 -- If this is the class_wide type of a constrained subtype, it does
18786 -- not have discriminants.
18788 Set_Has_Discriminants (CW_Type,
18789 Has_Discriminants (T) and then not Is_Constrained (T));
18791 Set_Has_Unknown_Discriminants (CW_Type, True);
18792 Set_Class_Wide_Type (T, CW_Type);
18793 Set_Equivalent_Type (CW_Type, Empty);
18795 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18797 Set_Class_Wide_Type (CW_Type, CW_Type);
18798 end Make_Class_Wide_Type;
18804 procedure Make_Index
18806 Related_Nod : Node_Id;
18807 Related_Id : Entity_Id := Empty;
18808 Suffix_Index : Nat := 1;
18809 In_Iter_Schm : Boolean := False)
18813 Def_Id : Entity_Id := Empty;
18814 Found : Boolean := False;
18817 -- For a discrete range used in a constrained array definition and
18818 -- defined by a range, an implicit conversion to the predefined type
18819 -- INTEGER is assumed if each bound is either a numeric literal, a named
18820 -- number, or an attribute, and the type of both bounds (prior to the
18821 -- implicit conversion) is the type universal_integer. Otherwise, both
18822 -- bounds must be of the same discrete type, other than universal
18823 -- integer; this type must be determinable independently of the
18824 -- context, but using the fact that the type must be discrete and that
18825 -- both bounds must have the same type.
18827 -- Character literals also have a universal type in the absence of
18828 -- of additional context, and are resolved to Standard_Character.
18830 if Nkind (N) = N_Range then
18832 -- The index is given by a range constraint. The bounds are known
18833 -- to be of a consistent type.
18835 if not Is_Overloaded (N) then
18838 -- For universal bounds, choose the specific predefined type
18840 if T = Universal_Integer then
18841 T := Standard_Integer;
18843 elsif T = Any_Character then
18844 Ambiguous_Character (Low_Bound (N));
18846 T := Standard_Character;
18849 -- The node may be overloaded because some user-defined operators
18850 -- are available, but if a universal interpretation exists it is
18851 -- also the selected one.
18853 elsif Universal_Interpretation (N) = Universal_Integer then
18854 T := Standard_Integer;
18860 Ind : Interp_Index;
18864 Get_First_Interp (N, Ind, It);
18865 while Present (It.Typ) loop
18866 if Is_Discrete_Type (It.Typ) then
18869 and then not Covers (It.Typ, T)
18870 and then not Covers (T, It.Typ)
18872 Error_Msg_N ("ambiguous bounds in discrete range", N);
18880 Get_Next_Interp (Ind, It);
18883 if T = Any_Type then
18884 Error_Msg_N ("discrete type required for range", N);
18885 Set_Etype (N, Any_Type);
18888 elsif T = Universal_Integer then
18889 T := Standard_Integer;
18894 if not Is_Discrete_Type (T) then
18895 Error_Msg_N ("discrete type required for range", N);
18896 Set_Etype (N, Any_Type);
18900 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18901 and then Attribute_Name (Low_Bound (N)) = Name_First
18902 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18903 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18904 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18906 -- The type of the index will be the type of the prefix, as long
18907 -- as the upper bound is 'Last of the same type.
18909 Def_Id := Entity (Prefix (Low_Bound (N)));
18911 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18912 or else Attribute_Name (High_Bound (N)) /= Name_Last
18913 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18914 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18921 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18923 elsif Nkind (N) = N_Subtype_Indication then
18925 -- The index is given by a subtype with a range constraint
18927 T := Base_Type (Entity (Subtype_Mark (N)));
18929 if not Is_Discrete_Type (T) then
18930 Error_Msg_N ("discrete type required for range", N);
18931 Set_Etype (N, Any_Type);
18935 R := Range_Expression (Constraint (N));
18938 Process_Range_Expr_In_Decl
18939 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18941 elsif Nkind (N) = N_Attribute_Reference then
18943 -- Catch beginner's error (use of attribute other than 'Range)
18945 if Attribute_Name (N) /= Name_Range then
18946 Error_Msg_N ("expect attribute ''Range", N);
18947 Set_Etype (N, Any_Type);
18951 -- If the node denotes the range of a type mark, that is also the
18952 -- resulting type, and we do not need to create an Itype for it.
18954 if Is_Entity_Name (Prefix (N))
18955 and then Comes_From_Source (N)
18956 and then Is_Type (Entity (Prefix (N)))
18957 and then Is_Discrete_Type (Entity (Prefix (N)))
18959 Def_Id := Entity (Prefix (N));
18962 Analyze_And_Resolve (N);
18966 -- If none of the above, must be a subtype. We convert this to a
18967 -- range attribute reference because in the case of declared first
18968 -- named subtypes, the types in the range reference can be different
18969 -- from the type of the entity. A range attribute normalizes the
18970 -- reference and obtains the correct types for the bounds.
18972 -- This transformation is in the nature of an expansion, is only
18973 -- done if expansion is active. In particular, it is not done on
18974 -- formal generic types, because we need to retain the name of the
18975 -- original index for instantiation purposes.
18978 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18979 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18980 Set_Etype (N, Any_Integer);
18984 -- The type mark may be that of an incomplete type. It is only
18985 -- now that we can get the full view, previous analysis does
18986 -- not look specifically for a type mark.
18988 Set_Entity (N, Get_Full_View (Entity (N)));
18989 Set_Etype (N, Entity (N));
18990 Def_Id := Entity (N);
18992 if not Is_Discrete_Type (Def_Id) then
18993 Error_Msg_N ("discrete type required for index", N);
18994 Set_Etype (N, Any_Type);
18999 if Expander_Active then
19001 Make_Attribute_Reference (Sloc (N),
19002 Attribute_Name => Name_Range,
19003 Prefix => Relocate_Node (N)));
19005 -- The original was a subtype mark that does not freeze. This
19006 -- means that the rewritten version must not freeze either.
19008 Set_Must_Not_Freeze (N);
19009 Set_Must_Not_Freeze (Prefix (N));
19010 Analyze_And_Resolve (N);
19014 -- If expander is inactive, type is legal, nothing else to construct
19021 if not Is_Discrete_Type (T) then
19022 Error_Msg_N ("discrete type required for range", N);
19023 Set_Etype (N, Any_Type);
19026 elsif T = Any_Type then
19027 Set_Etype (N, Any_Type);
19031 -- We will now create the appropriate Itype to describe the range, but
19032 -- first a check. If we originally had a subtype, then we just label
19033 -- the range with this subtype. Not only is there no need to construct
19034 -- a new subtype, but it is wrong to do so for two reasons:
19036 -- 1. A legality concern, if we have a subtype, it must not freeze,
19037 -- and the Itype would cause freezing incorrectly
19039 -- 2. An efficiency concern, if we created an Itype, it would not be
19040 -- recognized as the same type for the purposes of eliminating
19041 -- checks in some circumstances.
19043 -- We signal this case by setting the subtype entity in Def_Id
19045 if No (Def_Id) then
19047 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
19048 Set_Etype (Def_Id, Base_Type (T));
19050 if Is_Signed_Integer_Type (T) then
19051 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
19053 elsif Is_Modular_Integer_Type (T) then
19054 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
19057 Set_Ekind (Def_Id, E_Enumeration_Subtype);
19058 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
19059 Set_First_Literal (Def_Id, First_Literal (T));
19062 Set_Size_Info (Def_Id, (T));
19063 Set_RM_Size (Def_Id, RM_Size (T));
19064 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
19066 Set_Scalar_Range (Def_Id, R);
19067 Conditional_Delay (Def_Id, T);
19069 if Nkind (N) = N_Subtype_Indication then
19070 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
19073 -- In the subtype indication case, if the immediate parent of the
19074 -- new subtype is non-static, then the subtype we create is non-
19075 -- static, even if its bounds are static.
19077 if Nkind (N) = N_Subtype_Indication
19078 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
19080 Set_Is_Non_Static_Subtype (Def_Id);
19084 -- Final step is to label the index with this constructed type
19086 Set_Etype (N, Def_Id);
19089 ------------------------------
19090 -- Modular_Type_Declaration --
19091 ------------------------------
19093 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19094 Mod_Expr : constant Node_Id := Expression (Def);
19097 procedure Set_Modular_Size (Bits : Int);
19098 -- Sets RM_Size to Bits, and Esize to normal word size above this
19100 ----------------------
19101 -- Set_Modular_Size --
19102 ----------------------
19104 procedure Set_Modular_Size (Bits : Int) is
19106 Set_RM_Size (T, UI_From_Int (Bits));
19111 elsif Bits <= 16 then
19112 Init_Esize (T, 16);
19114 elsif Bits <= 32 then
19115 Init_Esize (T, 32);
19118 Init_Esize (T, System_Max_Binary_Modulus_Power);
19121 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
19122 Set_Is_Known_Valid (T);
19124 end Set_Modular_Size;
19126 -- Start of processing for Modular_Type_Declaration
19129 -- If the mod expression is (exactly) 2 * literal, where literal is
19130 -- 64 or less,then almost certainly the * was meant to be **. Warn.
19132 if Warn_On_Suspicious_Modulus_Value
19133 and then Nkind (Mod_Expr) = N_Op_Multiply
19134 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
19135 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
19136 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
19137 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
19140 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
19143 -- Proceed with analysis of mod expression
19145 Analyze_And_Resolve (Mod_Expr, Any_Integer);
19147 Set_Ekind (T, E_Modular_Integer_Type);
19148 Init_Alignment (T);
19149 Set_Is_Constrained (T);
19151 if not Is_OK_Static_Expression (Mod_Expr) then
19152 Flag_Non_Static_Expr
19153 ("non-static expression used for modular type bound!", Mod_Expr);
19154 M_Val := 2 ** System_Max_Binary_Modulus_Power;
19156 M_Val := Expr_Value (Mod_Expr);
19160 Error_Msg_N ("modulus value must be positive", Mod_Expr);
19161 M_Val := 2 ** System_Max_Binary_Modulus_Power;
19164 if M_Val > 2 ** Standard_Long_Integer_Size then
19165 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
19168 Set_Modulus (T, M_Val);
19170 -- Create bounds for the modular type based on the modulus given in
19171 -- the type declaration and then analyze and resolve those bounds.
19173 Set_Scalar_Range (T,
19174 Make_Range (Sloc (Mod_Expr),
19175 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
19176 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
19178 -- Properly analyze the literals for the range. We do this manually
19179 -- because we can't go calling Resolve, since we are resolving these
19180 -- bounds with the type, and this type is certainly not complete yet.
19182 Set_Etype (Low_Bound (Scalar_Range (T)), T);
19183 Set_Etype (High_Bound (Scalar_Range (T)), T);
19184 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
19185 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
19187 -- Loop through powers of two to find number of bits required
19189 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
19193 if M_Val = 2 ** Bits then
19194 Set_Modular_Size (Bits);
19199 elsif M_Val < 2 ** Bits then
19200 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
19201 Set_Non_Binary_Modulus (T);
19203 if Bits > System_Max_Nonbinary_Modulus_Power then
19204 Error_Msg_Uint_1 :=
19205 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
19207 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
19208 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19212 -- In the nonbinary case, set size as per RM 13.3(55)
19214 Set_Modular_Size (Bits);
19221 -- If we fall through, then the size exceed System.Max_Binary_Modulus
19222 -- so we just signal an error and set the maximum size.
19224 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
19225 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
19227 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19228 Init_Alignment (T);
19230 end Modular_Type_Declaration;
19232 --------------------------
19233 -- New_Concatenation_Op --
19234 --------------------------
19236 procedure New_Concatenation_Op (Typ : Entity_Id) is
19237 Loc : constant Source_Ptr := Sloc (Typ);
19240 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
19241 -- Create abbreviated declaration for the formal of a predefined
19242 -- Operator 'Op' of type 'Typ'
19244 --------------------
19245 -- Make_Op_Formal --
19246 --------------------
19248 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
19249 Formal : Entity_Id;
19251 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
19252 Set_Etype (Formal, Typ);
19253 Set_Mechanism (Formal, Default_Mechanism);
19255 end Make_Op_Formal;
19257 -- Start of processing for New_Concatenation_Op
19260 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
19262 Set_Ekind (Op, E_Operator);
19263 Set_Scope (Op, Current_Scope);
19264 Set_Etype (Op, Typ);
19265 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
19266 Set_Is_Immediately_Visible (Op);
19267 Set_Is_Intrinsic_Subprogram (Op);
19268 Set_Has_Completion (Op);
19269 Append_Entity (Op, Current_Scope);
19271 Set_Name_Entity_Id (Name_Op_Concat, Op);
19273 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19274 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19275 end New_Concatenation_Op;
19277 -------------------------
19278 -- OK_For_Limited_Init --
19279 -------------------------
19281 -- ???Check all calls of this, and compare the conditions under which it's
19284 function OK_For_Limited_Init
19286 Exp : Node_Id) return Boolean
19289 return Is_CPP_Constructor_Call (Exp)
19290 or else (Ada_Version >= Ada_2005
19291 and then not Debug_Flag_Dot_L
19292 and then OK_For_Limited_Init_In_05 (Typ, Exp));
19293 end OK_For_Limited_Init;
19295 -------------------------------
19296 -- OK_For_Limited_Init_In_05 --
19297 -------------------------------
19299 function OK_For_Limited_Init_In_05
19301 Exp : Node_Id) return Boolean
19304 -- An object of a limited interface type can be initialized with any
19305 -- expression of a nonlimited descendant type. However this does not
19306 -- apply if this is a view conversion of some other expression. This
19307 -- is checked below.
19309 if Is_Class_Wide_Type (Typ)
19310 and then Is_Limited_Interface (Typ)
19311 and then not Is_Limited_Type (Etype (Exp))
19312 and then Nkind (Exp) /= N_Type_Conversion
19317 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
19318 -- case of limited aggregates (including extension aggregates), and
19319 -- function calls. The function call may have been given in prefixed
19320 -- notation, in which case the original node is an indexed component.
19321 -- If the function is parameterless, the original node was an explicit
19322 -- dereference. The function may also be parameterless, in which case
19323 -- the source node is just an identifier.
19325 -- A branch of a conditional expression may have been removed if the
19326 -- condition is statically known. This happens during expansion, and
19327 -- thus will not happen if previous errors were encountered. The check
19328 -- will have been performed on the chosen branch, which replaces the
19329 -- original conditional expression.
19335 case Nkind (Original_Node (Exp)) is
19337 | N_Extension_Aggregate
19343 when N_Identifier =>
19344 return Present (Entity (Original_Node (Exp)))
19345 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
19347 when N_Qualified_Expression =>
19349 OK_For_Limited_Init_In_05
19350 (Typ, Expression (Original_Node (Exp)));
19352 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
19353 -- with a function call, the expander has rewritten the call into an
19354 -- N_Type_Conversion node to force displacement of the pointer to
19355 -- reference the component containing the secondary dispatch table.
19356 -- Otherwise a type conversion is not a legal context.
19357 -- A return statement for a build-in-place function returning a
19358 -- synchronized type also introduces an unchecked conversion.
19360 when N_Type_Conversion
19361 | N_Unchecked_Type_Conversion
19363 return not Comes_From_Source (Exp)
19365 OK_For_Limited_Init_In_05
19366 (Typ, Expression (Original_Node (Exp)));
19368 when N_Explicit_Dereference
19369 | N_Indexed_Component
19370 | N_Selected_Component
19372 return Nkind (Exp) = N_Function_Call;
19374 -- A use of 'Input is a function call, hence allowed. Normally the
19375 -- attribute will be changed to a call, but the attribute by itself
19376 -- can occur with -gnatc.
19378 when N_Attribute_Reference =>
19379 return Attribute_Name (Original_Node (Exp)) = Name_Input;
19381 -- "return raise ..." is OK
19383 when N_Raise_Expression =>
19386 -- For a case expression, all dependent expressions must be legal
19388 when N_Case_Expression =>
19393 Alt := First (Alternatives (Original_Node (Exp)));
19394 while Present (Alt) loop
19395 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
19405 -- For an if expression, all dependent expressions must be legal
19407 when N_If_Expression =>
19409 Then_Expr : constant Node_Id :=
19410 Next (First (Expressions (Original_Node (Exp))));
19411 Else_Expr : constant Node_Id := Next (Then_Expr);
19413 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
19415 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
19421 end OK_For_Limited_Init_In_05;
19423 -------------------------------------------
19424 -- Ordinary_Fixed_Point_Type_Declaration --
19425 -------------------------------------------
19427 procedure Ordinary_Fixed_Point_Type_Declaration
19431 Loc : constant Source_Ptr := Sloc (Def);
19432 Delta_Expr : constant Node_Id := Delta_Expression (Def);
19433 RRS : constant Node_Id := Real_Range_Specification (Def);
19434 Implicit_Base : Entity_Id;
19441 Check_Restriction (No_Fixed_Point, Def);
19443 -- Create implicit base type
19446 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
19447 Set_Etype (Implicit_Base, Implicit_Base);
19449 -- Analyze and process delta expression
19451 Analyze_And_Resolve (Delta_Expr, Any_Real);
19453 Check_Delta_Expression (Delta_Expr);
19454 Delta_Val := Expr_Value_R (Delta_Expr);
19456 Set_Delta_Value (Implicit_Base, Delta_Val);
19458 -- Compute default small from given delta, which is the largest power
19459 -- of two that does not exceed the given delta value.
19469 if Delta_Val < Ureal_1 then
19470 while Delta_Val < Tmp loop
19471 Tmp := Tmp / Ureal_2;
19472 Scale := Scale + 1;
19477 Tmp := Tmp * Ureal_2;
19478 exit when Tmp > Delta_Val;
19479 Scale := Scale - 1;
19483 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
19486 Set_Small_Value (Implicit_Base, Small_Val);
19488 -- If no range was given, set a dummy range
19490 if RRS <= Empty_Or_Error then
19491 Low_Val := -Small_Val;
19492 High_Val := Small_Val;
19494 -- Otherwise analyze and process given range
19498 Low : constant Node_Id := Low_Bound (RRS);
19499 High : constant Node_Id := High_Bound (RRS);
19502 Analyze_And_Resolve (Low, Any_Real);
19503 Analyze_And_Resolve (High, Any_Real);
19504 Check_Real_Bound (Low);
19505 Check_Real_Bound (High);
19507 -- Obtain and set the range
19509 Low_Val := Expr_Value_R (Low);
19510 High_Val := Expr_Value_R (High);
19512 if Low_Val > High_Val then
19513 Error_Msg_NE ("??fixed point type& has null range", Def, T);
19518 -- The range for both the implicit base and the declared first subtype
19519 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
19520 -- set a temporary range in place. Note that the bounds of the base
19521 -- type will be widened to be symmetrical and to fill the available
19522 -- bits when the type is frozen.
19524 -- We could do this with all discrete types, and probably should, but
19525 -- we absolutely have to do it for fixed-point, since the end-points
19526 -- of the range and the size are determined by the small value, which
19527 -- could be reset before the freeze point.
19529 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
19530 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
19532 -- Complete definition of first subtype. The inheritance of the rep item
19533 -- chain ensures that SPARK-related pragmas are not clobbered when the
19534 -- ordinary fixed point type acts as a full view of a private type.
19536 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
19537 Set_Etype (T, Implicit_Base);
19538 Init_Size_Align (T);
19539 Inherit_Rep_Item_Chain (T, Implicit_Base);
19540 Set_Small_Value (T, Small_Val);
19541 Set_Delta_Value (T, Delta_Val);
19542 Set_Is_Constrained (T);
19543 end Ordinary_Fixed_Point_Type_Declaration;
19545 ----------------------------------
19546 -- Preanalyze_Assert_Expression --
19547 ----------------------------------
19549 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19551 In_Assertion_Expr := In_Assertion_Expr + 1;
19552 Preanalyze_Spec_Expression (N, T);
19553 In_Assertion_Expr := In_Assertion_Expr - 1;
19554 end Preanalyze_Assert_Expression;
19556 -----------------------------------
19557 -- Preanalyze_Default_Expression --
19558 -----------------------------------
19560 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19561 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19563 In_Default_Expr := True;
19564 Preanalyze_Spec_Expression (N, T);
19565 In_Default_Expr := Save_In_Default_Expr;
19566 end Preanalyze_Default_Expression;
19568 --------------------------------
19569 -- Preanalyze_Spec_Expression --
19570 --------------------------------
19572 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19573 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19575 In_Spec_Expression := True;
19576 Preanalyze_And_Resolve (N, T);
19577 In_Spec_Expression := Save_In_Spec_Expression;
19578 end Preanalyze_Spec_Expression;
19580 ----------------------------------------
19581 -- Prepare_Private_Subtype_Completion --
19582 ----------------------------------------
19584 procedure Prepare_Private_Subtype_Completion
19586 Related_Nod : Node_Id)
19588 Id_B : constant Entity_Id := Base_Type (Id);
19589 Full_B : Entity_Id := Full_View (Id_B);
19593 if Present (Full_B) then
19595 -- Get to the underlying full view if necessary
19597 if Is_Private_Type (Full_B)
19598 and then Present (Underlying_Full_View (Full_B))
19600 Full_B := Underlying_Full_View (Full_B);
19603 -- The Base_Type is already completed, we can complete the subtype
19604 -- now. We have to create a new entity with the same name, Thus we
19605 -- can't use Create_Itype.
19607 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19608 Set_Is_Itype (Full);
19609 Set_Associated_Node_For_Itype (Full, Related_Nod);
19610 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19613 -- The parent subtype may be private, but the base might not, in some
19614 -- nested instances. In that case, the subtype does not need to be
19615 -- exchanged. It would still be nice to make private subtypes and their
19616 -- bases consistent at all times ???
19618 if Is_Private_Type (Id_B) then
19619 Append_Elmt (Id, Private_Dependents (Id_B));
19621 end Prepare_Private_Subtype_Completion;
19623 ---------------------------
19624 -- Process_Discriminants --
19625 ---------------------------
19627 procedure Process_Discriminants
19629 Prev : Entity_Id := Empty)
19631 Elist : constant Elist_Id := New_Elmt_List;
19634 Discr_Number : Uint;
19635 Discr_Type : Entity_Id;
19636 Default_Present : Boolean := False;
19637 Default_Not_Present : Boolean := False;
19640 -- A composite type other than an array type can have discriminants.
19641 -- On entry, the current scope is the composite type.
19643 -- The discriminants are initially entered into the scope of the type
19644 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19645 -- use, as explained at the end of this procedure.
19647 Discr := First (Discriminant_Specifications (N));
19648 while Present (Discr) loop
19649 Enter_Name (Defining_Identifier (Discr));
19651 -- For navigation purposes we add a reference to the discriminant
19652 -- in the entity for the type. If the current declaration is a
19653 -- completion, place references on the partial view. Otherwise the
19654 -- type is the current scope.
19656 if Present (Prev) then
19658 -- The references go on the partial view, if present. If the
19659 -- partial view has discriminants, the references have been
19660 -- generated already.
19662 if not Has_Discriminants (Prev) then
19663 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19667 (Current_Scope, Defining_Identifier (Discr), 'd');
19670 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19671 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19673 -- Ada 2005 (AI-254)
19675 if Present (Access_To_Subprogram_Definition
19676 (Discriminant_Type (Discr)))
19677 and then Protected_Present (Access_To_Subprogram_Definition
19678 (Discriminant_Type (Discr)))
19681 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19685 Find_Type (Discriminant_Type (Discr));
19686 Discr_Type := Etype (Discriminant_Type (Discr));
19688 if Error_Posted (Discriminant_Type (Discr)) then
19689 Discr_Type := Any_Type;
19693 -- Handling of discriminants that are access types
19695 if Is_Access_Type (Discr_Type) then
19697 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19698 -- limited record types
19700 if Ada_Version < Ada_2005 then
19701 Check_Access_Discriminant_Requires_Limited
19702 (Discr, Discriminant_Type (Discr));
19705 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19707 ("(Ada 83) access discriminant not allowed", Discr);
19710 -- If not access type, must be a discrete type
19712 elsif not Is_Discrete_Type (Discr_Type) then
19714 ("discriminants must have a discrete or access type",
19715 Discriminant_Type (Discr));
19718 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19720 -- If a discriminant specification includes the assignment compound
19721 -- delimiter followed by an expression, the expression is the default
19722 -- expression of the discriminant; the default expression must be of
19723 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19724 -- a default expression, we do the special preanalysis, since this
19725 -- expression does not freeze (see section "Handling of Default and
19726 -- Per-Object Expressions" in spec of package Sem).
19728 if Present (Expression (Discr)) then
19729 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19733 if Nkind (N) = N_Formal_Type_Declaration then
19735 ("discriminant defaults not allowed for formal type",
19736 Expression (Discr));
19738 -- Flag an error for a tagged type with defaulted discriminants,
19739 -- excluding limited tagged types when compiling for Ada 2012
19740 -- (see AI05-0214).
19742 elsif Is_Tagged_Type (Current_Scope)
19743 and then (not Is_Limited_Type (Current_Scope)
19744 or else Ada_Version < Ada_2012)
19745 and then Comes_From_Source (N)
19747 -- Note: see similar test in Check_Or_Process_Discriminants, to
19748 -- handle the (illegal) case of the completion of an untagged
19749 -- view with discriminants with defaults by a tagged full view.
19750 -- We skip the check if Discr does not come from source, to
19751 -- account for the case of an untagged derived type providing
19752 -- defaults for a renamed discriminant from a private untagged
19753 -- ancestor with a tagged full view (ACATS B460006).
19755 if Ada_Version >= Ada_2012 then
19757 ("discriminants of nonlimited tagged type cannot have"
19759 Expression (Discr));
19762 ("discriminants of tagged type cannot have defaults",
19763 Expression (Discr));
19767 Default_Present := True;
19768 Append_Elmt (Expression (Discr), Elist);
19770 -- Tag the defining identifiers for the discriminants with
19771 -- their corresponding default expressions from the tree.
19773 Set_Discriminant_Default_Value
19774 (Defining_Identifier (Discr), Expression (Discr));
19777 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19778 -- gets set unless we can be sure that no range check is required.
19780 if (GNATprove_Mode or not Expander_Active)
19783 (Expression (Discr), Discr_Type, Assume_Valid => True)
19785 Set_Do_Range_Check (Expression (Discr));
19788 -- No default discriminant value given
19791 Default_Not_Present := True;
19794 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19795 -- Discr_Type but with the null-exclusion attribute
19797 if Ada_Version >= Ada_2005 then
19799 -- Ada 2005 (AI-231): Static checks
19801 if Can_Never_Be_Null (Discr_Type) then
19802 Null_Exclusion_Static_Checks (Discr);
19804 elsif Is_Access_Type (Discr_Type)
19805 and then Null_Exclusion_Present (Discr)
19807 -- No need to check itypes because in their case this check
19808 -- was done at their point of creation
19810 and then not Is_Itype (Discr_Type)
19812 if Can_Never_Be_Null (Discr_Type) then
19814 ("`NOT NULL` not allowed (& already excludes null)",
19819 Set_Etype (Defining_Identifier (Discr),
19820 Create_Null_Excluding_Itype
19822 Related_Nod => Discr));
19824 -- Check for improper null exclusion if the type is otherwise
19825 -- legal for a discriminant.
19827 elsif Null_Exclusion_Present (Discr)
19828 and then Is_Discrete_Type (Discr_Type)
19831 ("null exclusion can only apply to an access type", Discr);
19834 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19835 -- can't have defaults. Synchronized types, or types that are
19836 -- explicitly limited are fine, but special tests apply to derived
19837 -- types in generics: in a generic body we have to assume the
19838 -- worst, and therefore defaults are not allowed if the parent is
19839 -- a generic formal private type (see ACATS B370001).
19841 if Is_Access_Type (Discr_Type) and then Default_Present then
19842 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19843 or else Is_Limited_Record (Current_Scope)
19844 or else Is_Concurrent_Type (Current_Scope)
19845 or else Is_Concurrent_Record_Type (Current_Scope)
19846 or else Ekind (Current_Scope) = E_Limited_Private_Type
19848 if not Is_Derived_Type (Current_Scope)
19849 or else not Is_Generic_Type (Etype (Current_Scope))
19850 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19851 or else Limited_Present
19852 (Type_Definition (Parent (Current_Scope)))
19858 ("access discriminants of nonlimited types cannot "
19859 & "have defaults", Expression (Discr));
19862 elsif Present (Expression (Discr)) then
19864 ("(Ada 2005) access discriminants of nonlimited types "
19865 & "cannot have defaults", Expression (Discr));
19870 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19871 -- This check is relevant only when SPARK_Mode is on as it is not a
19872 -- standard Ada legality rule.
19875 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19877 Error_Msg_N ("discriminant cannot be volatile", Discr);
19883 -- An element list consisting of the default expressions of the
19884 -- discriminants is constructed in the above loop and used to set
19885 -- the Discriminant_Constraint attribute for the type. If an object
19886 -- is declared of this (record or task) type without any explicit
19887 -- discriminant constraint given, this element list will form the
19888 -- actual parameters for the corresponding initialization procedure
19891 Set_Discriminant_Constraint (Current_Scope, Elist);
19892 Set_Stored_Constraint (Current_Scope, No_Elist);
19894 -- Default expressions must be provided either for all or for none
19895 -- of the discriminants of a discriminant part. (RM 3.7.1)
19897 if Default_Present and then Default_Not_Present then
19899 ("incomplete specification of defaults for discriminants", N);
19902 -- The use of the name of a discriminant is not allowed in default
19903 -- expressions of a discriminant part if the specification of the
19904 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19906 -- To detect this, the discriminant names are entered initially with an
19907 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19908 -- attempt to use a void entity (for example in an expression that is
19909 -- type-checked) produces the error message: premature usage. Now after
19910 -- completing the semantic analysis of the discriminant part, we can set
19911 -- the Ekind of all the discriminants appropriately.
19913 Discr := First (Discriminant_Specifications (N));
19914 Discr_Number := Uint_1;
19915 while Present (Discr) loop
19916 Id := Defining_Identifier (Discr);
19917 Set_Ekind (Id, E_Discriminant);
19918 Init_Component_Location (Id);
19920 Set_Discriminant_Number (Id, Discr_Number);
19922 -- Make sure this is always set, even in illegal programs
19924 Set_Corresponding_Discriminant (Id, Empty);
19926 -- Initialize the Original_Record_Component to the entity itself.
19927 -- Inherit_Components will propagate the right value to
19928 -- discriminants in derived record types.
19930 Set_Original_Record_Component (Id, Id);
19932 -- Create the discriminal for the discriminant
19934 Build_Discriminal (Id);
19937 Discr_Number := Discr_Number + 1;
19940 Set_Has_Discriminants (Current_Scope);
19941 end Process_Discriminants;
19943 -----------------------
19944 -- Process_Full_View --
19945 -----------------------
19947 -- WARNING: This routine manages Ghost regions. Return statements must be
19948 -- replaced by gotos which jump to the end of the routine and restore the
19951 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19952 procedure Collect_Implemented_Interfaces
19954 Ifaces : Elist_Id);
19955 -- Ada 2005: Gather all the interfaces that Typ directly or
19956 -- inherently implements. Duplicate entries are not added to
19957 -- the list Ifaces.
19959 ------------------------------------
19960 -- Collect_Implemented_Interfaces --
19961 ------------------------------------
19963 procedure Collect_Implemented_Interfaces
19968 Iface_Elmt : Elmt_Id;
19971 -- Abstract interfaces are only associated with tagged record types
19973 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19977 -- Recursively climb to the ancestors
19979 if Etype (Typ) /= Typ
19981 -- Protect the frontend against wrong cyclic declarations like:
19983 -- type B is new A with private;
19984 -- type C is new A with private;
19986 -- type B is new C with null record;
19987 -- type C is new B with null record;
19989 and then Etype (Typ) /= Priv_T
19990 and then Etype (Typ) /= Full_T
19992 -- Keep separate the management of private type declarations
19994 if Ekind (Typ) = E_Record_Type_With_Private then
19996 -- Handle the following illegal usage:
19997 -- type Private_Type is tagged private;
19999 -- type Private_Type is new Type_Implementing_Iface;
20001 if Present (Full_View (Typ))
20002 and then Etype (Typ) /= Full_View (Typ)
20004 if Is_Interface (Etype (Typ)) then
20005 Append_Unique_Elmt (Etype (Typ), Ifaces);
20008 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
20011 -- Non-private types
20014 if Is_Interface (Etype (Typ)) then
20015 Append_Unique_Elmt (Etype (Typ), Ifaces);
20018 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
20022 -- Handle entities in the list of abstract interfaces
20024 if Present (Interfaces (Typ)) then
20025 Iface_Elmt := First_Elmt (Interfaces (Typ));
20026 while Present (Iface_Elmt) loop
20027 Iface := Node (Iface_Elmt);
20029 pragma Assert (Is_Interface (Iface));
20031 if not Contain_Interface (Iface, Ifaces) then
20032 Append_Elmt (Iface, Ifaces);
20033 Collect_Implemented_Interfaces (Iface, Ifaces);
20036 Next_Elmt (Iface_Elmt);
20039 end Collect_Implemented_Interfaces;
20043 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
20045 Full_Indic : Node_Id;
20046 Full_Parent : Entity_Id;
20047 Priv_Parent : Entity_Id;
20049 -- Start of processing for Process_Full_View
20052 Mark_And_Set_Ghost_Completion (N, Priv_T);
20054 -- First some sanity checks that must be done after semantic
20055 -- decoration of the full view and thus cannot be placed with other
20056 -- similar checks in Find_Type_Name
20058 if not Is_Limited_Type (Priv_T)
20059 and then (Is_Limited_Type (Full_T)
20060 or else Is_Limited_Composite (Full_T))
20062 if In_Instance then
20066 ("completion of nonlimited type cannot be limited", Full_T);
20067 Explain_Limited_Type (Full_T, Full_T);
20070 elsif Is_Abstract_Type (Full_T)
20071 and then not Is_Abstract_Type (Priv_T)
20074 ("completion of nonabstract type cannot be abstract", Full_T);
20076 elsif Is_Tagged_Type (Priv_T)
20077 and then Is_Limited_Type (Priv_T)
20078 and then not Is_Limited_Type (Full_T)
20080 -- If pragma CPP_Class was applied to the private declaration
20081 -- propagate the limitedness to the full-view
20083 if Is_CPP_Class (Priv_T) then
20084 Set_Is_Limited_Record (Full_T);
20086 -- GNAT allow its own definition of Limited_Controlled to disobey
20087 -- this rule in order in ease the implementation. This test is safe
20088 -- because Root_Controlled is defined in a child of System that
20089 -- normal programs are not supposed to use.
20091 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
20092 Set_Is_Limited_Composite (Full_T);
20095 ("completion of limited tagged type must be limited", Full_T);
20098 elsif Is_Generic_Type (Priv_T) then
20099 Error_Msg_N ("generic type cannot have a completion", Full_T);
20102 -- Check that ancestor interfaces of private and full views are
20103 -- consistent. We omit this check for synchronized types because
20104 -- they are performed on the corresponding record type when frozen.
20106 if Ada_Version >= Ada_2005
20107 and then Is_Tagged_Type (Priv_T)
20108 and then Is_Tagged_Type (Full_T)
20109 and then not Is_Concurrent_Type (Full_T)
20113 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
20114 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
20117 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
20118 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
20120 -- Ada 2005 (AI-251): The partial view shall be a descendant of
20121 -- an interface type if and only if the full type is descendant
20122 -- of the interface type (AARM 7.3 (7.3/2)).
20124 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
20126 if Present (Iface) then
20128 ("interface in partial view& not implemented by full type "
20129 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
20132 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
20134 if Present (Iface) then
20136 ("interface & not implemented by partial view "
20137 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
20142 if Is_Tagged_Type (Priv_T)
20143 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20144 and then Is_Derived_Type (Full_T)
20146 Priv_Parent := Etype (Priv_T);
20148 -- The full view of a private extension may have been transformed
20149 -- into an unconstrained derived type declaration and a subtype
20150 -- declaration (see build_derived_record_type for details).
20152 if Nkind (N) = N_Subtype_Declaration then
20153 Full_Indic := Subtype_Indication (N);
20154 Full_Parent := Etype (Base_Type (Full_T));
20156 Full_Indic := Subtype_Indication (Type_Definition (N));
20157 Full_Parent := Etype (Full_T);
20160 -- Check that the parent type of the full type is a descendant of
20161 -- the ancestor subtype given in the private extension. If either
20162 -- entity has an Etype equal to Any_Type then we had some previous
20163 -- error situation [7.3(8)].
20165 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
20168 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
20169 -- any order. Therefore we don't have to check that its parent must
20170 -- be a descendant of the parent of the private type declaration.
20172 elsif Is_Interface (Priv_Parent)
20173 and then Is_Interface (Full_Parent)
20177 -- Ada 2005 (AI-251): If the parent of the private type declaration
20178 -- is an interface there is no need to check that it is an ancestor
20179 -- of the associated full type declaration. The required tests for
20180 -- this case are performed by Build_Derived_Record_Type.
20182 elsif not Is_Interface (Base_Type (Priv_Parent))
20183 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
20186 ("parent of full type must descend from parent of private "
20187 & "extension", Full_Indic);
20189 -- First check a formal restriction, and then proceed with checking
20190 -- Ada rules. Since the formal restriction is not a serious error, we
20191 -- don't prevent further error detection for this check, hence the
20195 -- In formal mode, when completing a private extension the type
20196 -- named in the private part must be exactly the same as that
20197 -- named in the visible part.
20199 if Priv_Parent /= Full_Parent then
20200 Error_Msg_Name_1 := Chars (Priv_Parent);
20201 Check_SPARK_05_Restriction ("% expected", Full_Indic);
20204 -- Check the rules of 7.3(10): if the private extension inherits
20205 -- known discriminants, then the full type must also inherit those
20206 -- discriminants from the same (ancestor) type, and the parent
20207 -- subtype of the full type must be constrained if and only if
20208 -- the ancestor subtype of the private extension is constrained.
20210 if No (Discriminant_Specifications (Parent (Priv_T)))
20211 and then not Has_Unknown_Discriminants (Priv_T)
20212 and then Has_Discriminants (Base_Type (Priv_Parent))
20215 Priv_Indic : constant Node_Id :=
20216 Subtype_Indication (Parent (Priv_T));
20218 Priv_Constr : constant Boolean :=
20219 Is_Constrained (Priv_Parent)
20221 Nkind (Priv_Indic) = N_Subtype_Indication
20223 Is_Constrained (Entity (Priv_Indic));
20225 Full_Constr : constant Boolean :=
20226 Is_Constrained (Full_Parent)
20228 Nkind (Full_Indic) = N_Subtype_Indication
20230 Is_Constrained (Entity (Full_Indic));
20232 Priv_Discr : Entity_Id;
20233 Full_Discr : Entity_Id;
20236 Priv_Discr := First_Discriminant (Priv_Parent);
20237 Full_Discr := First_Discriminant (Full_Parent);
20238 while Present (Priv_Discr) and then Present (Full_Discr) loop
20239 if Original_Record_Component (Priv_Discr) =
20240 Original_Record_Component (Full_Discr)
20242 Corresponding_Discriminant (Priv_Discr) =
20243 Corresponding_Discriminant (Full_Discr)
20250 Next_Discriminant (Priv_Discr);
20251 Next_Discriminant (Full_Discr);
20254 if Present (Priv_Discr) or else Present (Full_Discr) then
20256 ("full view must inherit discriminants of the parent "
20257 & "type used in the private extension", Full_Indic);
20259 elsif Priv_Constr and then not Full_Constr then
20261 ("parent subtype of full type must be constrained",
20264 elsif Full_Constr and then not Priv_Constr then
20266 ("parent subtype of full type must be unconstrained",
20271 -- Check the rules of 7.3(12): if a partial view has neither
20272 -- known or unknown discriminants, then the full type
20273 -- declaration shall define a definite subtype.
20275 elsif not Has_Unknown_Discriminants (Priv_T)
20276 and then not Has_Discriminants (Priv_T)
20277 and then not Is_Constrained (Full_T)
20280 ("full view must define a constrained type if partial view "
20281 & "has no discriminants", Full_T);
20284 -- ??????? Do we implement the following properly ?????
20285 -- If the ancestor subtype of a private extension has constrained
20286 -- discriminants, then the parent subtype of the full view shall
20287 -- impose a statically matching constraint on those discriminants
20292 -- For untagged types, verify that a type without discriminants is
20293 -- not completed with an unconstrained type. A separate error message
20294 -- is produced if the full type has defaulted discriminants.
20296 if Is_Definite_Subtype (Priv_T)
20297 and then not Is_Definite_Subtype (Full_T)
20299 Error_Msg_Sloc := Sloc (Parent (Priv_T));
20301 ("full view of& not compatible with declaration#",
20304 if not Is_Tagged_Type (Full_T) then
20306 ("\one is constrained, the other unconstrained", Full_T);
20311 -- AI-419: verify that the use of "limited" is consistent
20314 Orig_Decl : constant Node_Id := Original_Node (N);
20317 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20318 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
20320 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
20322 if not Limited_Present (Parent (Priv_T))
20323 and then not Synchronized_Present (Parent (Priv_T))
20324 and then Limited_Present (Type_Definition (Orig_Decl))
20327 ("full view of non-limited extension cannot be limited", N);
20329 -- Conversely, if the partial view carries the limited keyword,
20330 -- the full view must as well, even if it may be redundant.
20332 elsif Limited_Present (Parent (Priv_T))
20333 and then not Limited_Present (Type_Definition (Orig_Decl))
20336 ("full view of limited extension must be explicitly limited",
20342 -- Ada 2005 (AI-443): A synchronized private extension must be
20343 -- completed by a task or protected type.
20345 if Ada_Version >= Ada_2005
20346 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20347 and then Synchronized_Present (Parent (Priv_T))
20348 and then not Is_Concurrent_Type (Full_T)
20350 Error_Msg_N ("full view of synchronized extension must " &
20351 "be synchronized type", N);
20354 -- Ada 2005 AI-363: if the full view has discriminants with
20355 -- defaults, it is illegal to declare constrained access subtypes
20356 -- whose designated type is the current type. This allows objects
20357 -- of the type that are declared in the heap to be unconstrained.
20359 if not Has_Unknown_Discriminants (Priv_T)
20360 and then not Has_Discriminants (Priv_T)
20361 and then Has_Discriminants (Full_T)
20363 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
20365 Set_Has_Constrained_Partial_View (Full_T);
20366 Set_Has_Constrained_Partial_View (Priv_T);
20369 -- Create a full declaration for all its subtypes recorded in
20370 -- Private_Dependents and swap them similarly to the base type. These
20371 -- are subtypes that have been define before the full declaration of
20372 -- the private type. We also swap the entry in Private_Dependents list
20373 -- so we can properly restore the private view on exit from the scope.
20376 Priv_Elmt : Elmt_Id;
20377 Priv_Scop : Entity_Id;
20382 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
20383 while Present (Priv_Elmt) loop
20384 Priv := Node (Priv_Elmt);
20385 Priv_Scop := Scope (Priv);
20387 if Ekind_In (Priv, E_Private_Subtype,
20388 E_Limited_Private_Subtype,
20389 E_Record_Subtype_With_Private)
20391 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
20392 Set_Is_Itype (Full);
20393 Set_Parent (Full, Parent (Priv));
20394 Set_Associated_Node_For_Itype (Full, N);
20396 -- Now we need to complete the private subtype, but since the
20397 -- base type has already been swapped, we must also swap the
20398 -- subtypes (and thus, reverse the arguments in the call to
20399 -- Complete_Private_Subtype). Also note that we may need to
20400 -- re-establish the scope of the private subtype.
20402 Copy_And_Swap (Priv, Full);
20404 if not In_Open_Scopes (Priv_Scop) then
20405 Push_Scope (Priv_Scop);
20408 -- Reset Priv_Scop to Empty to indicate no scope was pushed
20410 Priv_Scop := Empty;
20413 Complete_Private_Subtype (Full, Priv, Full_T, N);
20415 if Present (Priv_Scop) then
20419 Replace_Elmt (Priv_Elmt, Full);
20422 Next_Elmt (Priv_Elmt);
20426 -- If the private view was tagged, copy the new primitive operations
20427 -- from the private view to the full view.
20429 if Is_Tagged_Type (Full_T) then
20431 Disp_Typ : Entity_Id;
20432 Full_List : Elist_Id;
20434 Prim_Elmt : Elmt_Id;
20435 Priv_List : Elist_Id;
20439 L : Elist_Id) return Boolean;
20440 -- Determine whether list L contains element E
20448 L : Elist_Id) return Boolean
20450 List_Elmt : Elmt_Id;
20453 List_Elmt := First_Elmt (L);
20454 while Present (List_Elmt) loop
20455 if Node (List_Elmt) = E then
20459 Next_Elmt (List_Elmt);
20465 -- Start of processing
20468 if Is_Tagged_Type (Priv_T) then
20469 Priv_List := Primitive_Operations (Priv_T);
20470 Prim_Elmt := First_Elmt (Priv_List);
20472 -- In the case of a concurrent type completing a private tagged
20473 -- type, primitives may have been declared in between the two
20474 -- views. These subprograms need to be wrapped the same way
20475 -- entries and protected procedures are handled because they
20476 -- cannot be directly shared by the two views.
20478 if Is_Concurrent_Type (Full_T) then
20480 Conc_Typ : constant Entity_Id :=
20481 Corresponding_Record_Type (Full_T);
20482 Curr_Nod : Node_Id := Parent (Conc_Typ);
20483 Wrap_Spec : Node_Id;
20486 while Present (Prim_Elmt) loop
20487 Prim := Node (Prim_Elmt);
20489 if Comes_From_Source (Prim)
20490 and then not Is_Abstract_Subprogram (Prim)
20493 Make_Subprogram_Declaration (Sloc (Prim),
20497 Obj_Typ => Conc_Typ,
20499 Parameter_Specifications
20502 Insert_After (Curr_Nod, Wrap_Spec);
20503 Curr_Nod := Wrap_Spec;
20505 Analyze (Wrap_Spec);
20507 -- Remove the wrapper from visibility to avoid
20508 -- spurious conflict with the wrapped entity.
20510 Set_Is_Immediately_Visible
20511 (Defining_Entity (Specification (Wrap_Spec)),
20515 Next_Elmt (Prim_Elmt);
20521 -- For non-concurrent types, transfer explicit primitives, but
20522 -- omit those inherited from the parent of the private view
20523 -- since they will be re-inherited later on.
20526 Full_List := Primitive_Operations (Full_T);
20528 while Present (Prim_Elmt) loop
20529 Prim := Node (Prim_Elmt);
20531 if Comes_From_Source (Prim)
20532 and then not Contains (Prim, Full_List)
20534 Append_Elmt (Prim, Full_List);
20537 Next_Elmt (Prim_Elmt);
20541 -- Untagged private view
20544 Full_List := Primitive_Operations (Full_T);
20546 -- In this case the partial view is untagged, so here we locate
20547 -- all of the earlier primitives that need to be treated as
20548 -- dispatching (those that appear between the two views). Note
20549 -- that these additional operations must all be new operations
20550 -- (any earlier operations that override inherited operations
20551 -- of the full view will already have been inserted in the
20552 -- primitives list, marked by Check_Operation_From_Private_View
20553 -- as dispatching. Note that implicit "/=" operators are
20554 -- excluded from being added to the primitives list since they
20555 -- shouldn't be treated as dispatching (tagged "/=" is handled
20558 Prim := Next_Entity (Full_T);
20559 while Present (Prim) and then Prim /= Priv_T loop
20560 if Ekind_In (Prim, E_Procedure, E_Function) then
20561 Disp_Typ := Find_Dispatching_Type (Prim);
20563 if Disp_Typ = Full_T
20564 and then (Chars (Prim) /= Name_Op_Ne
20565 or else Comes_From_Source (Prim))
20567 Check_Controlling_Formals (Full_T, Prim);
20569 if not Is_Dispatching_Operation (Prim) then
20570 Append_Elmt (Prim, Full_List);
20571 Set_Is_Dispatching_Operation (Prim, True);
20572 Set_DT_Position_Value (Prim, No_Uint);
20575 elsif Is_Dispatching_Operation (Prim)
20576 and then Disp_Typ /= Full_T
20579 -- Verify that it is not otherwise controlled by a
20580 -- formal or a return value of type T.
20582 Check_Controlling_Formals (Disp_Typ, Prim);
20586 Next_Entity (Prim);
20590 -- For the tagged case, the two views can share the same primitive
20591 -- operations list and the same class-wide type. Update attributes
20592 -- of the class-wide type which depend on the full declaration.
20594 if Is_Tagged_Type (Priv_T) then
20595 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20596 Set_Class_Wide_Type
20597 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20599 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20604 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20606 if Known_To_Have_Preelab_Init (Priv_T) then
20608 -- Case where there is a pragma Preelaborable_Initialization. We
20609 -- always allow this in predefined units, which is cheating a bit,
20610 -- but it means we don't have to struggle to meet the requirements in
20611 -- the RM for having Preelaborable Initialization. Otherwise we
20612 -- require that the type meets the RM rules. But we can't check that
20613 -- yet, because of the rule about overriding Initialize, so we simply
20614 -- set a flag that will be checked at freeze time.
20616 if not In_Predefined_Unit (Full_T) then
20617 Set_Must_Have_Preelab_Init (Full_T);
20621 -- If pragma CPP_Class was applied to the private type declaration,
20622 -- propagate it now to the full type declaration.
20624 if Is_CPP_Class (Priv_T) then
20625 Set_Is_CPP_Class (Full_T);
20626 Set_Convention (Full_T, Convention_CPP);
20628 -- Check that components of imported CPP types do not have default
20631 Check_CPP_Type_Has_No_Defaults (Full_T);
20634 -- If the private view has user specified stream attributes, then so has
20637 -- Why the test, how could these flags be already set in Full_T ???
20639 if Has_Specified_Stream_Read (Priv_T) then
20640 Set_Has_Specified_Stream_Read (Full_T);
20643 if Has_Specified_Stream_Write (Priv_T) then
20644 Set_Has_Specified_Stream_Write (Full_T);
20647 if Has_Specified_Stream_Input (Priv_T) then
20648 Set_Has_Specified_Stream_Input (Full_T);
20651 if Has_Specified_Stream_Output (Priv_T) then
20652 Set_Has_Specified_Stream_Output (Full_T);
20655 -- Propagate Default_Initial_Condition-related attributes from the
20656 -- partial view to the full view and its base type.
20658 Propagate_DIC_Attributes (Full_T, From_Typ => Priv_T);
20659 Propagate_DIC_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20661 -- Propagate invariant-related attributes from the partial view to the
20662 -- full view and its base type.
20664 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20665 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20667 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20668 -- in the full view without advertising the inheritance in the partial
20669 -- view. This can only occur when the partial view has no parent type
20670 -- and the full view has an interface as a parent. Any other scenarios
20671 -- are illegal because implemented interfaces must match between the
20674 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20676 Full_Par : constant Entity_Id := Etype (Full_T);
20677 Priv_Par : constant Entity_Id := Etype (Priv_T);
20680 if not Is_Interface (Priv_Par)
20681 and then Is_Interface (Full_Par)
20682 and then Has_Inheritable_Invariants (Full_Par)
20685 ("hidden inheritance of class-wide type invariants not "
20691 -- Propagate predicates to full type, and predicate function if already
20692 -- defined. It is not clear that this can actually happen? the partial
20693 -- view cannot be frozen yet, and the predicate function has not been
20694 -- built. Still it is a cheap check and seems safer to make it.
20696 if Has_Predicates (Priv_T) then
20697 Set_Has_Predicates (Full_T);
20699 if Present (Predicate_Function (Priv_T)) then
20700 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20705 Restore_Ghost_Mode (Saved_GM);
20706 end Process_Full_View;
20708 -----------------------------------
20709 -- Process_Incomplete_Dependents --
20710 -----------------------------------
20712 procedure Process_Incomplete_Dependents
20714 Full_T : Entity_Id;
20717 Inc_Elmt : Elmt_Id;
20718 Priv_Dep : Entity_Id;
20719 New_Subt : Entity_Id;
20721 Disc_Constraint : Elist_Id;
20724 if No (Private_Dependents (Inc_T)) then
20728 -- Itypes that may be generated by the completion of an incomplete
20729 -- subtype are not used by the back-end and not attached to the tree.
20730 -- They are created only for constraint-checking purposes.
20732 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20733 while Present (Inc_Elmt) loop
20734 Priv_Dep := Node (Inc_Elmt);
20736 if Ekind (Priv_Dep) = E_Subprogram_Type then
20738 -- An Access_To_Subprogram type may have a return type or a
20739 -- parameter type that is incomplete. Replace with the full view.
20741 if Etype (Priv_Dep) = Inc_T then
20742 Set_Etype (Priv_Dep, Full_T);
20746 Formal : Entity_Id;
20749 Formal := First_Formal (Priv_Dep);
20750 while Present (Formal) loop
20751 if Etype (Formal) = Inc_T then
20752 Set_Etype (Formal, Full_T);
20755 Next_Formal (Formal);
20759 elsif Is_Overloadable (Priv_Dep) then
20761 -- If a subprogram in the incomplete dependents list is primitive
20762 -- for a tagged full type then mark it as a dispatching operation,
20763 -- check whether it overrides an inherited subprogram, and check
20764 -- restrictions on its controlling formals. Note that a protected
20765 -- operation is never dispatching: only its wrapper operation
20766 -- (which has convention Ada) is.
20768 if Is_Tagged_Type (Full_T)
20769 and then Is_Primitive (Priv_Dep)
20770 and then Convention (Priv_Dep) /= Convention_Protected
20772 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20773 Set_Is_Dispatching_Operation (Priv_Dep);
20774 Check_Controlling_Formals (Full_T, Priv_Dep);
20777 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20779 -- Can happen during processing of a body before the completion
20780 -- of a TA type. Ignore, because spec is also on dependent list.
20784 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20785 -- corresponding subtype of the full view.
20787 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype
20788 and then Comes_From_Source (Priv_Dep)
20790 Set_Subtype_Indication
20791 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20792 Set_Etype (Priv_Dep, Full_T);
20793 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20794 Set_Analyzed (Parent (Priv_Dep), False);
20796 -- Reanalyze the declaration, suppressing the call to Enter_Name
20797 -- to avoid duplicate names.
20799 Analyze_Subtype_Declaration
20800 (N => Parent (Priv_Dep),
20803 -- Dependent is a subtype
20806 -- We build a new subtype indication using the full view of the
20807 -- incomplete parent. The discriminant constraints have been
20808 -- elaborated already at the point of the subtype declaration.
20810 New_Subt := Create_Itype (E_Void, N);
20812 if Has_Discriminants (Full_T) then
20813 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20815 Disc_Constraint := No_Elist;
20818 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20819 Set_Full_View (Priv_Dep, New_Subt);
20822 Next_Elmt (Inc_Elmt);
20824 end Process_Incomplete_Dependents;
20826 --------------------------------
20827 -- Process_Range_Expr_In_Decl --
20828 --------------------------------
20830 procedure Process_Range_Expr_In_Decl
20833 Subtyp : Entity_Id := Empty;
20834 Check_List : List_Id := Empty_List;
20835 R_Check_Off : Boolean := False;
20836 In_Iter_Schm : Boolean := False)
20839 R_Checks : Check_Result;
20840 Insert_Node : Node_Id;
20841 Def_Id : Entity_Id;
20844 Analyze_And_Resolve (R, Base_Type (T));
20846 if Nkind (R) = N_Range then
20848 -- In SPARK, all ranges should be static, with the exception of the
20849 -- discrete type definition of a loop parameter specification.
20851 if not In_Iter_Schm
20852 and then not Is_OK_Static_Range (R)
20854 Check_SPARK_05_Restriction ("range should be static", R);
20857 Lo := Low_Bound (R);
20858 Hi := High_Bound (R);
20860 -- Validity checks on the range of a quantified expression are
20861 -- delayed until the construct is transformed into a loop.
20863 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20864 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20868 -- We need to ensure validity of the bounds here, because if we
20869 -- go ahead and do the expansion, then the expanded code will get
20870 -- analyzed with range checks suppressed and we miss the check.
20872 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20873 -- the temporaries generated by routine Remove_Side_Effects by means
20874 -- of validity checks must use the same names. When a range appears
20875 -- in the parent of a generic, the range is processed with checks
20876 -- disabled as part of the generic context and with checks enabled
20877 -- for code generation purposes. This leads to link issues as the
20878 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20879 -- template sees the temporaries generated by Remove_Side_Effects.
20882 Validity_Check_Range (R, Subtyp);
20885 -- If there were errors in the declaration, try and patch up some
20886 -- common mistakes in the bounds. The cases handled are literals
20887 -- which are Integer where the expected type is Real and vice versa.
20888 -- These corrections allow the compilation process to proceed further
20889 -- along since some basic assumptions of the format of the bounds
20892 if Etype (R) = Any_Type then
20893 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20895 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20897 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20899 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20901 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20903 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20905 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20907 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20914 -- If the bounds of the range have been mistakenly given as string
20915 -- literals (perhaps in place of character literals), then an error
20916 -- has already been reported, but we rewrite the string literal as a
20917 -- bound of the range's type to avoid blowups in later processing
20918 -- that looks at static values.
20920 if Nkind (Lo) = N_String_Literal then
20922 Make_Attribute_Reference (Sloc (Lo),
20923 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20924 Attribute_Name => Name_First));
20925 Analyze_And_Resolve (Lo);
20928 if Nkind (Hi) = N_String_Literal then
20930 Make_Attribute_Reference (Sloc (Hi),
20931 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20932 Attribute_Name => Name_First));
20933 Analyze_And_Resolve (Hi);
20936 -- If bounds aren't scalar at this point then exit, avoiding
20937 -- problems with further processing of the range in this procedure.
20939 if not Is_Scalar_Type (Etype (Lo)) then
20943 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20944 -- then range of the base type. Here we check whether the bounds
20945 -- are in the range of the subtype itself. Note that if the bounds
20946 -- represent the null range the Constraint_Error exception should
20949 -- ??? The following code should be cleaned up as follows
20951 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20952 -- is done in the call to Range_Check (R, T); below
20954 -- 2. The use of R_Check_Off should be investigated and possibly
20955 -- removed, this would clean up things a bit.
20957 if Is_Null_Range (Lo, Hi) then
20961 -- Capture values of bounds and generate temporaries for them
20962 -- if needed, before applying checks, since checks may cause
20963 -- duplication of the expression without forcing evaluation.
20965 -- The forced evaluation removes side effects from expressions,
20966 -- which should occur also in GNATprove mode. Otherwise, we end up
20967 -- with unexpected insertions of actions at places where this is
20968 -- not supposed to occur, e.g. on default parameters of a call.
20970 if Expander_Active or GNATprove_Mode then
20972 -- Call Force_Evaluation to create declarations as needed to
20973 -- deal with side effects, and also create typ_FIRST/LAST
20974 -- entities for bounds if we have a subtype name.
20976 -- Note: we do this transformation even if expansion is not
20977 -- active if we are in GNATprove_Mode since the transformation
20978 -- is in general required to ensure that the resulting tree has
20979 -- proper Ada semantics.
20982 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20984 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20987 -- We use a flag here instead of suppressing checks on the type
20988 -- because the type we check against isn't necessarily the place
20989 -- where we put the check.
20991 if not R_Check_Off then
20992 R_Checks := Get_Range_Checks (R, T);
20994 -- Look up tree to find an appropriate insertion point. We
20995 -- can't just use insert_actions because later processing
20996 -- depends on the insertion node. Prior to Ada 2012 the
20997 -- insertion point could only be a declaration or a loop, but
20998 -- quantified expressions can appear within any context in an
20999 -- expression, and the insertion point can be any statement,
21000 -- pragma, or declaration.
21002 Insert_Node := Parent (R);
21003 while Present (Insert_Node) loop
21005 Nkind (Insert_Node) in N_Declaration
21008 (Insert_Node, N_Component_Declaration,
21009 N_Loop_Parameter_Specification,
21010 N_Function_Specification,
21011 N_Procedure_Specification);
21013 exit when Nkind (Insert_Node) in N_Later_Decl_Item
21014 or else Nkind (Insert_Node) in
21015 N_Statement_Other_Than_Procedure_Call
21016 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
21019 Insert_Node := Parent (Insert_Node);
21022 -- Why would Type_Decl not be present??? Without this test,
21023 -- short regression tests fail.
21025 if Present (Insert_Node) then
21027 -- Case of loop statement. Verify that the range is part
21028 -- of the subtype indication of the iteration scheme.
21030 if Nkind (Insert_Node) = N_Loop_Statement then
21035 Indic := Parent (R);
21036 while Present (Indic)
21037 and then Nkind (Indic) /= N_Subtype_Indication
21039 Indic := Parent (Indic);
21042 if Present (Indic) then
21043 Def_Id := Etype (Subtype_Mark (Indic));
21045 Insert_Range_Checks
21049 Sloc (Insert_Node),
21051 Do_Before => True);
21055 -- Insertion before a declaration. If the declaration
21056 -- includes discriminants, the list of applicable checks
21057 -- is given by the caller.
21059 elsif Nkind (Insert_Node) in N_Declaration then
21060 Def_Id := Defining_Identifier (Insert_Node);
21062 if (Ekind (Def_Id) = E_Record_Type
21063 and then Depends_On_Discriminant (R))
21065 (Ekind (Def_Id) = E_Protected_Type
21066 and then Has_Discriminants (Def_Id))
21068 Append_Range_Checks
21070 Check_List, Def_Id, Sloc (Insert_Node), R);
21073 Insert_Range_Checks
21075 Insert_Node, Def_Id, Sloc (Insert_Node), R);
21079 -- Insertion before a statement. Range appears in the
21080 -- context of a quantified expression. Insertion will
21081 -- take place when expression is expanded.
21090 -- Case of other than an explicit N_Range node
21092 -- The forced evaluation removes side effects from expressions, which
21093 -- should occur also in GNATprove mode. Otherwise, we end up with
21094 -- unexpected insertions of actions at places where this is not
21095 -- supposed to occur, e.g. on default parameters of a call.
21097 elsif Expander_Active or GNATprove_Mode then
21098 Get_Index_Bounds (R, Lo, Hi);
21099 Force_Evaluation (Lo);
21100 Force_Evaluation (Hi);
21102 end Process_Range_Expr_In_Decl;
21104 --------------------------------------
21105 -- Process_Real_Range_Specification --
21106 --------------------------------------
21108 procedure Process_Real_Range_Specification (Def : Node_Id) is
21109 Spec : constant Node_Id := Real_Range_Specification (Def);
21112 Err : Boolean := False;
21114 procedure Analyze_Bound (N : Node_Id);
21115 -- Analyze and check one bound
21117 -------------------
21118 -- Analyze_Bound --
21119 -------------------
21121 procedure Analyze_Bound (N : Node_Id) is
21123 Analyze_And_Resolve (N, Any_Real);
21125 if not Is_OK_Static_Expression (N) then
21126 Flag_Non_Static_Expr
21127 ("bound in real type definition is not static!", N);
21132 -- Start of processing for Process_Real_Range_Specification
21135 if Present (Spec) then
21136 Lo := Low_Bound (Spec);
21137 Hi := High_Bound (Spec);
21138 Analyze_Bound (Lo);
21139 Analyze_Bound (Hi);
21141 -- If error, clear away junk range specification
21144 Set_Real_Range_Specification (Def, Empty);
21147 end Process_Real_Range_Specification;
21149 ---------------------
21150 -- Process_Subtype --
21151 ---------------------
21153 function Process_Subtype
21155 Related_Nod : Node_Id;
21156 Related_Id : Entity_Id := Empty;
21157 Suffix : Character := ' ') return Entity_Id
21160 Def_Id : Entity_Id;
21161 Error_Node : Node_Id;
21162 Full_View_Id : Entity_Id;
21163 Subtype_Mark_Id : Entity_Id;
21165 May_Have_Null_Exclusion : Boolean;
21167 procedure Check_Incomplete (T : Node_Id);
21168 -- Called to verify that an incomplete type is not used prematurely
21170 ----------------------
21171 -- Check_Incomplete --
21172 ----------------------
21174 procedure Check_Incomplete (T : Node_Id) is
21176 -- Ada 2005 (AI-412): Incomplete subtypes are legal
21178 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
21180 not (Ada_Version >= Ada_2005
21182 (Nkind (Parent (T)) = N_Subtype_Declaration
21183 or else (Nkind (Parent (T)) = N_Subtype_Indication
21184 and then Nkind (Parent (Parent (T))) =
21185 N_Subtype_Declaration)))
21187 Error_Msg_N ("invalid use of type before its full declaration", T);
21189 end Check_Incomplete;
21191 -- Start of processing for Process_Subtype
21194 -- Case of no constraints present
21196 if Nkind (S) /= N_Subtype_Indication then
21198 Check_Incomplete (S);
21201 -- Ada 2005 (AI-231): Static check
21203 if Ada_Version >= Ada_2005
21204 and then Present (P)
21205 and then Null_Exclusion_Present (P)
21206 and then Nkind (P) /= N_Access_To_Object_Definition
21207 and then not Is_Access_Type (Entity (S))
21209 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
21212 -- The following is ugly, can't we have a range or even a flag???
21214 May_Have_Null_Exclusion :=
21215 Nkind_In (P, N_Access_Definition,
21216 N_Access_Function_Definition,
21217 N_Access_Procedure_Definition,
21218 N_Access_To_Object_Definition,
21220 N_Component_Definition)
21222 Nkind_In (P, N_Derived_Type_Definition,
21223 N_Discriminant_Specification,
21224 N_Formal_Object_Declaration,
21225 N_Object_Declaration,
21226 N_Object_Renaming_Declaration,
21227 N_Parameter_Specification,
21228 N_Subtype_Declaration);
21230 -- Create an Itype that is a duplicate of Entity (S) but with the
21231 -- null-exclusion attribute.
21233 if May_Have_Null_Exclusion
21234 and then Is_Access_Type (Entity (S))
21235 and then Null_Exclusion_Present (P)
21237 -- No need to check the case of an access to object definition.
21238 -- It is correct to define double not-null pointers.
21241 -- type Not_Null_Int_Ptr is not null access Integer;
21242 -- type Acc is not null access Not_Null_Int_Ptr;
21244 and then Nkind (P) /= N_Access_To_Object_Definition
21246 if Can_Never_Be_Null (Entity (S)) then
21247 case Nkind (Related_Nod) is
21248 when N_Full_Type_Declaration =>
21249 if Nkind (Type_Definition (Related_Nod))
21250 in N_Array_Type_Definition
21254 (Component_Definition
21255 (Type_Definition (Related_Nod)));
21258 Subtype_Indication (Type_Definition (Related_Nod));
21261 when N_Subtype_Declaration =>
21262 Error_Node := Subtype_Indication (Related_Nod);
21264 when N_Object_Declaration =>
21265 Error_Node := Object_Definition (Related_Nod);
21267 when N_Component_Declaration =>
21269 Subtype_Indication (Component_Definition (Related_Nod));
21271 when N_Allocator =>
21272 Error_Node := Expression (Related_Nod);
21275 pragma Assert (False);
21276 Error_Node := Related_Nod;
21280 ("`NOT NULL` not allowed (& already excludes null)",
21286 Create_Null_Excluding_Itype
21288 Related_Nod => P));
21289 Set_Entity (S, Etype (S));
21294 -- Case of constraint present, so that we have an N_Subtype_Indication
21295 -- node (this node is created only if constraints are present).
21298 Find_Type (Subtype_Mark (S));
21300 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
21302 (Nkind (Parent (S)) = N_Subtype_Declaration
21303 and then Is_Itype (Defining_Identifier (Parent (S))))
21305 Check_Incomplete (Subtype_Mark (S));
21309 Subtype_Mark_Id := Entity (Subtype_Mark (S));
21311 -- Explicit subtype declaration case
21313 if Nkind (P) = N_Subtype_Declaration then
21314 Def_Id := Defining_Identifier (P);
21316 -- Explicit derived type definition case
21318 elsif Nkind (P) = N_Derived_Type_Definition then
21319 Def_Id := Defining_Identifier (Parent (P));
21321 -- Implicit case, the Def_Id must be created as an implicit type.
21322 -- The one exception arises in the case of concurrent types, array
21323 -- and access types, where other subsidiary implicit types may be
21324 -- created and must appear before the main implicit type. In these
21325 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
21326 -- has not yet been called to create Def_Id.
21329 if Is_Array_Type (Subtype_Mark_Id)
21330 or else Is_Concurrent_Type (Subtype_Mark_Id)
21331 or else Is_Access_Type (Subtype_Mark_Id)
21335 -- For the other cases, we create a new unattached Itype,
21336 -- and set the indication to ensure it gets attached later.
21340 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21344 -- If the kind of constraint is invalid for this kind of type,
21345 -- then give an error, and then pretend no constraint was given.
21347 if not Is_Valid_Constraint_Kind
21348 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
21351 ("incorrect constraint for this kind of type", Constraint (S));
21353 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
21355 -- Set Ekind of orphan itype, to prevent cascaded errors
21357 if Present (Def_Id) then
21358 Set_Ekind (Def_Id, Ekind (Any_Type));
21361 -- Make recursive call, having got rid of the bogus constraint
21363 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
21366 -- Remaining processing depends on type. Select on Base_Type kind to
21367 -- ensure getting to the concrete type kind in the case of a private
21368 -- subtype (needed when only doing semantic analysis).
21370 case Ekind (Base_Type (Subtype_Mark_Id)) is
21371 when Access_Kind =>
21373 -- If this is a constraint on a class-wide type, discard it.
21374 -- There is currently no way to express a partial discriminant
21375 -- constraint on a type with unknown discriminants. This is
21376 -- a pathology that the ACATS wisely decides not to test.
21378 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
21379 if Comes_From_Source (S) then
21381 ("constraint on class-wide type ignored??",
21385 if Nkind (P) = N_Subtype_Declaration then
21386 Set_Subtype_Indication (P,
21387 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
21390 return Subtype_Mark_Id;
21393 Constrain_Access (Def_Id, S, Related_Nod);
21396 and then Is_Itype (Designated_Type (Def_Id))
21397 and then Nkind (Related_Nod) = N_Subtype_Declaration
21398 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
21400 Build_Itype_Reference
21401 (Designated_Type (Def_Id), Related_Nod);
21405 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
21407 when Decimal_Fixed_Point_Kind =>
21408 Constrain_Decimal (Def_Id, S);
21410 when Enumeration_Kind =>
21411 Constrain_Enumeration (Def_Id, S);
21412 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21414 when Ordinary_Fixed_Point_Kind =>
21415 Constrain_Ordinary_Fixed (Def_Id, S);
21418 Constrain_Float (Def_Id, S);
21420 when Integer_Kind =>
21421 Constrain_Integer (Def_Id, S);
21422 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21424 when Class_Wide_Kind
21425 | E_Incomplete_Type
21429 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21431 if Ekind (Def_Id) = E_Incomplete_Type then
21432 Set_Private_Dependents (Def_Id, New_Elmt_List);
21435 when Private_Kind =>
21436 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21438 -- The base type may be private but Def_Id may be a full view
21441 if Is_Private_Type (Def_Id) then
21442 Set_Private_Dependents (Def_Id, New_Elmt_List);
21445 -- In case of an invalid constraint prevent further processing
21446 -- since the type constructed is missing expected fields.
21448 if Etype (Def_Id) = Any_Type then
21452 -- If the full view is that of a task with discriminants,
21453 -- we must constrain both the concurrent type and its
21454 -- corresponding record type. Otherwise we will just propagate
21455 -- the constraint to the full view, if available.
21457 if Present (Full_View (Subtype_Mark_Id))
21458 and then Has_Discriminants (Subtype_Mark_Id)
21459 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
21462 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21464 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
21465 Constrain_Concurrent (Full_View_Id, S,
21466 Related_Nod, Related_Id, Suffix);
21467 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
21468 Set_Full_View (Def_Id, Full_View_Id);
21470 -- Introduce an explicit reference to the private subtype,
21471 -- to prevent scope anomalies in gigi if first use appears
21472 -- in a nested context, e.g. a later function body.
21473 -- Should this be generated in other contexts than a full
21474 -- type declaration?
21476 if Is_Itype (Def_Id)
21478 Nkind (Parent (P)) = N_Full_Type_Declaration
21480 Build_Itype_Reference (Def_Id, Parent (P));
21484 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
21487 when Concurrent_Kind =>
21488 Constrain_Concurrent (Def_Id, S,
21489 Related_Nod, Related_Id, Suffix);
21492 Error_Msg_N ("invalid subtype mark in subtype indication", S);
21495 -- Size and Convention are always inherited from the base type
21497 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
21498 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
21502 end Process_Subtype;
21504 -----------------------------
21505 -- Record_Type_Declaration --
21506 -----------------------------
21508 procedure Record_Type_Declaration
21513 Def : constant Node_Id := Type_Definition (N);
21514 Is_Tagged : Boolean;
21515 Tag_Comp : Entity_Id;
21518 -- These flags must be initialized before calling Process_Discriminants
21519 -- because this routine makes use of them.
21521 Set_Ekind (T, E_Record_Type);
21523 Init_Size_Align (T);
21524 Set_Interfaces (T, No_Elist);
21525 Set_Stored_Constraint (T, No_Elist);
21526 Set_Default_SSO (T);
21527 Set_No_Reordering (T, No_Component_Reordering);
21531 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21532 if Limited_Present (Def) then
21533 Check_SPARK_05_Restriction ("limited is not allowed", N);
21536 if Abstract_Present (Def) then
21537 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21540 -- The flag Is_Tagged_Type might have already been set by
21541 -- Find_Type_Name if it detected an error for declaration T. This
21542 -- arises in the case of private tagged types where the full view
21543 -- omits the word tagged.
21546 Tagged_Present (Def)
21547 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21549 Set_Is_Limited_Record (T, Limited_Present (Def));
21552 Set_Is_Tagged_Type (T, True);
21553 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21556 -- Type is abstract if full declaration carries keyword, or if
21557 -- previous partial view did.
21559 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21560 or else Abstract_Present (Def));
21563 Check_SPARK_05_Restriction ("interface is not allowed", N);
21566 Analyze_Interface_Declaration (T, Def);
21568 if Present (Discriminant_Specifications (N)) then
21570 ("interface types cannot have discriminants",
21571 Defining_Identifier
21572 (First (Discriminant_Specifications (N))));
21576 -- First pass: if there are self-referential access components,
21577 -- create the required anonymous access type declarations, and if
21578 -- need be an incomplete type declaration for T itself.
21580 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21582 if Ada_Version >= Ada_2005
21583 and then Present (Interface_List (Def))
21585 Check_Interfaces (N, Def);
21588 Ifaces_List : Elist_Id;
21591 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21592 -- already in the parents.
21596 Ifaces_List => Ifaces_List,
21597 Exclude_Parents => True);
21599 Set_Interfaces (T, Ifaces_List);
21603 -- Records constitute a scope for the component declarations within.
21604 -- The scope is created prior to the processing of these declarations.
21605 -- Discriminants are processed first, so that they are visible when
21606 -- processing the other components. The Ekind of the record type itself
21607 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21609 -- Enter record scope
21613 -- If an incomplete or private type declaration was already given for
21614 -- the type, then this scope already exists, and the discriminants have
21615 -- been declared within. We must verify that the full declaration
21616 -- matches the incomplete one.
21618 Check_Or_Process_Discriminants (N, T, Prev);
21620 Set_Is_Constrained (T, not Has_Discriminants (T));
21621 Set_Has_Delayed_Freeze (T, True);
21623 -- For tagged types add a manually analyzed component corresponding
21624 -- to the component _tag, the corresponding piece of tree will be
21625 -- expanded as part of the freezing actions if it is not a CPP_Class.
21629 -- Do not add the tag unless we are in expansion mode
21631 if Expander_Active then
21632 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21633 Enter_Name (Tag_Comp);
21635 Set_Ekind (Tag_Comp, E_Component);
21636 Set_Is_Tag (Tag_Comp);
21637 Set_Is_Aliased (Tag_Comp);
21638 Set_Etype (Tag_Comp, RTE (RE_Tag));
21639 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21640 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21641 Init_Component_Location (Tag_Comp);
21643 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21644 -- implemented interfaces.
21646 if Has_Interfaces (T) then
21647 Add_Interface_Tag_Components (N, T);
21651 Make_Class_Wide_Type (T);
21652 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21655 -- We must suppress range checks when processing record components in
21656 -- the presence of discriminants, since we don't want spurious checks to
21657 -- be generated during their analysis, but Suppress_Range_Checks flags
21658 -- must be reset the after processing the record definition.
21660 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21661 -- couldn't we just use the normal range check suppression method here.
21662 -- That would seem cleaner ???
21664 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21665 Set_Kill_Range_Checks (T, True);
21666 Record_Type_Definition (Def, Prev);
21667 Set_Kill_Range_Checks (T, False);
21669 Record_Type_Definition (Def, Prev);
21672 -- Exit from record scope
21676 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21677 -- the implemented interfaces and associate them an aliased entity.
21680 and then not Is_Empty_List (Interface_List (Def))
21682 Derive_Progenitor_Subprograms (T, T);
21685 Check_Function_Writable_Actuals (N);
21686 end Record_Type_Declaration;
21688 ----------------------------
21689 -- Record_Type_Definition --
21690 ----------------------------
21692 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21693 Component : Entity_Id;
21694 Ctrl_Components : Boolean := False;
21695 Final_Storage_Only : Boolean;
21699 if Ekind (Prev_T) = E_Incomplete_Type then
21700 T := Full_View (Prev_T);
21705 -- In SPARK, tagged types and type extensions may only be declared in
21706 -- the specification of library unit packages.
21708 if Present (Def) and then Is_Tagged_Type (T) then
21714 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21715 Typ := Parent (Def);
21718 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21719 Typ := Parent (Parent (Def));
21722 Ctxt := Parent (Typ);
21724 if Nkind (Ctxt) = N_Package_Body
21725 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21727 Check_SPARK_05_Restriction
21728 ("type should be defined in package specification", Typ);
21730 elsif Nkind (Ctxt) /= N_Package_Specification
21731 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21733 Check_SPARK_05_Restriction
21734 ("type should be defined in library unit package", Typ);
21739 Final_Storage_Only := not Is_Controlled_Active (T);
21741 -- Ada 2005: Check whether an explicit Limited is present in a derived
21742 -- type declaration.
21744 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21745 and then Limited_Present (Parent (Def))
21747 Set_Is_Limited_Record (T);
21750 -- If the component list of a record type is defined by the reserved
21751 -- word null and there is no discriminant part, then the record type has
21752 -- no components and all records of the type are null records (RM 3.7)
21753 -- This procedure is also called to process the extension part of a
21754 -- record extension, in which case the current scope may have inherited
21758 or else No (Component_List (Def))
21759 or else Null_Present (Component_List (Def))
21761 if not Is_Tagged_Type (T) then
21762 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21766 Analyze_Declarations (Component_Items (Component_List (Def)));
21768 if Present (Variant_Part (Component_List (Def))) then
21769 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21770 Analyze (Variant_Part (Component_List (Def)));
21774 -- After completing the semantic analysis of the record definition,
21775 -- record components, both new and inherited, are accessible. Set their
21776 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21777 -- whose Ekind may be void.
21779 Component := First_Entity (Current_Scope);
21780 while Present (Component) loop
21781 if Ekind (Component) = E_Void
21782 and then not Is_Itype (Component)
21784 Set_Ekind (Component, E_Component);
21785 Init_Component_Location (Component);
21788 Propagate_Concurrent_Flags (T, Etype (Component));
21790 if Ekind (Component) /= E_Component then
21793 -- Do not set Has_Controlled_Component on a class-wide equivalent
21794 -- type. See Make_CW_Equivalent_Type.
21796 elsif not Is_Class_Wide_Equivalent_Type (T)
21797 and then (Has_Controlled_Component (Etype (Component))
21798 or else (Chars (Component) /= Name_uParent
21799 and then Is_Controlled_Active
21800 (Etype (Component))))
21802 Set_Has_Controlled_Component (T, True);
21803 Final_Storage_Only :=
21805 and then Finalize_Storage_Only (Etype (Component));
21806 Ctrl_Components := True;
21809 Next_Entity (Component);
21812 -- A Type is Finalize_Storage_Only only if all its controlled components
21815 if Ctrl_Components then
21816 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21819 -- Place reference to end record on the proper entity, which may
21820 -- be a partial view.
21822 if Present (Def) then
21823 Process_End_Label (Def, 'e', Prev_T);
21825 end Record_Type_Definition;
21827 ------------------------
21828 -- Replace_Components --
21829 ------------------------
21831 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21832 function Process (N : Node_Id) return Traverse_Result;
21838 function Process (N : Node_Id) return Traverse_Result is
21842 if Nkind (N) = N_Discriminant_Specification then
21843 Comp := First_Discriminant (Typ);
21844 while Present (Comp) loop
21845 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21846 Set_Defining_Identifier (N, Comp);
21850 Next_Discriminant (Comp);
21853 elsif Nkind (N) = N_Component_Declaration then
21854 Comp := First_Component (Typ);
21855 while Present (Comp) loop
21856 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21857 Set_Defining_Identifier (N, Comp);
21861 Next_Component (Comp);
21868 procedure Replace is new Traverse_Proc (Process);
21870 -- Start of processing for Replace_Components
21874 end Replace_Components;
21876 -------------------------------
21877 -- Set_Completion_Referenced --
21878 -------------------------------
21880 procedure Set_Completion_Referenced (E : Entity_Id) is
21882 -- If in main unit, mark entity that is a completion as referenced,
21883 -- warnings go on the partial view when needed.
21885 if In_Extended_Main_Source_Unit (E) then
21886 Set_Referenced (E);
21888 end Set_Completion_Referenced;
21890 ---------------------
21891 -- Set_Default_SSO --
21892 ---------------------
21894 procedure Set_Default_SSO (T : Entity_Id) is
21896 case Opt.Default_SSO is
21900 Set_SSO_Set_Low_By_Default (T, True);
21902 Set_SSO_Set_High_By_Default (T, True);
21904 raise Program_Error;
21906 end Set_Default_SSO;
21908 ---------------------
21909 -- Set_Fixed_Range --
21910 ---------------------
21912 -- The range for fixed-point types is complicated by the fact that we
21913 -- do not know the exact end points at the time of the declaration. This
21914 -- is true for three reasons:
21916 -- A size clause may affect the fudging of the end-points.
21917 -- A small clause may affect the values of the end-points.
21918 -- We try to include the end-points if it does not affect the size.
21920 -- This means that the actual end-points must be established at the
21921 -- point when the type is frozen. Meanwhile, we first narrow the range
21922 -- as permitted (so that it will fit if necessary in a small specified
21923 -- size), and then build a range subtree with these narrowed bounds.
21924 -- Set_Fixed_Range constructs the range from real literal values, and
21925 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21927 -- The parent of this range is set to point to the entity so that it is
21928 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21929 -- other scalar types, which are just pointers to the range in the
21930 -- original tree, this would otherwise be an orphan).
21932 -- The tree is left unanalyzed. When the type is frozen, the processing
21933 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21934 -- analyzed, and uses this as an indication that it should complete
21935 -- work on the range (it will know the final small and size values).
21937 procedure Set_Fixed_Range
21943 S : constant Node_Id :=
21945 Low_Bound => Make_Real_Literal (Loc, Lo),
21946 High_Bound => Make_Real_Literal (Loc, Hi));
21948 Set_Scalar_Range (E, S);
21951 -- Before the freeze point, the bounds of a fixed point are universal
21952 -- and carry the corresponding type.
21954 Set_Etype (Low_Bound (S), Universal_Real);
21955 Set_Etype (High_Bound (S), Universal_Real);
21956 end Set_Fixed_Range;
21958 ----------------------------------
21959 -- Set_Scalar_Range_For_Subtype --
21960 ----------------------------------
21962 procedure Set_Scalar_Range_For_Subtype
21963 (Def_Id : Entity_Id;
21967 Kind : constant Entity_Kind := Ekind (Def_Id);
21970 -- Defend against previous error
21972 if Nkind (R) = N_Error then
21976 Set_Scalar_Range (Def_Id, R);
21978 -- We need to link the range into the tree before resolving it so
21979 -- that types that are referenced, including importantly the subtype
21980 -- itself, are properly frozen (Freeze_Expression requires that the
21981 -- expression be properly linked into the tree). Of course if it is
21982 -- already linked in, then we do not disturb the current link.
21984 if No (Parent (R)) then
21985 Set_Parent (R, Def_Id);
21988 -- Reset the kind of the subtype during analysis of the range, to
21989 -- catch possible premature use in the bounds themselves.
21991 Set_Ekind (Def_Id, E_Void);
21992 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21993 Set_Ekind (Def_Id, Kind);
21994 end Set_Scalar_Range_For_Subtype;
21996 --------------------------------------------------------
21997 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21998 --------------------------------------------------------
22000 procedure Set_Stored_Constraint_From_Discriminant_Constraint
22004 -- Make sure set if encountered during Expand_To_Stored_Constraint
22006 Set_Stored_Constraint (E, No_Elist);
22008 -- Give it the right value
22010 if Is_Constrained (E) and then Has_Discriminants (E) then
22011 Set_Stored_Constraint (E,
22012 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
22014 end Set_Stored_Constraint_From_Discriminant_Constraint;
22016 -------------------------------------
22017 -- Signed_Integer_Type_Declaration --
22018 -------------------------------------
22020 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
22021 Implicit_Base : Entity_Id;
22022 Base_Typ : Entity_Id;
22025 Errs : Boolean := False;
22029 function Can_Derive_From (E : Entity_Id) return Boolean;
22030 -- Determine whether given bounds allow derivation from specified type
22032 procedure Check_Bound (Expr : Node_Id);
22033 -- Check bound to make sure it is integral and static. If not, post
22034 -- appropriate error message and set Errs flag
22036 ---------------------
22037 -- Can_Derive_From --
22038 ---------------------
22040 -- Note we check both bounds against both end values, to deal with
22041 -- strange types like ones with a range of 0 .. -12341234.
22043 function Can_Derive_From (E : Entity_Id) return Boolean is
22044 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
22045 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
22047 return Lo <= Lo_Val and then Lo_Val <= Hi
22049 Lo <= Hi_Val and then Hi_Val <= Hi;
22050 end Can_Derive_From;
22056 procedure Check_Bound (Expr : Node_Id) is
22058 -- If a range constraint is used as an integer type definition, each
22059 -- bound of the range must be defined by a static expression of some
22060 -- integer type, but the two bounds need not have the same integer
22061 -- type (Negative bounds are allowed.) (RM 3.5.4)
22063 if not Is_Integer_Type (Etype (Expr)) then
22065 ("integer type definition bounds must be of integer type", Expr);
22068 elsif not Is_OK_Static_Expression (Expr) then
22069 Flag_Non_Static_Expr
22070 ("non-static expression used for integer type bound!", Expr);
22073 -- The bounds are folded into literals, and we set their type to be
22074 -- universal, to avoid typing difficulties: we cannot set the type
22075 -- of the literal to the new type, because this would be a forward
22076 -- reference for the back end, and if the original type is user-
22077 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
22080 if Is_Entity_Name (Expr) then
22081 Fold_Uint (Expr, Expr_Value (Expr), True);
22084 Set_Etype (Expr, Universal_Integer);
22088 -- Start of processing for Signed_Integer_Type_Declaration
22091 -- Create an anonymous base type
22094 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
22096 -- Analyze and check the bounds, they can be of any integer type
22098 Lo := Low_Bound (Def);
22099 Hi := High_Bound (Def);
22101 -- Arbitrarily use Integer as the type if either bound had an error
22103 if Hi = Error or else Lo = Error then
22104 Base_Typ := Any_Integer;
22105 Set_Error_Posted (T, True);
22107 -- Here both bounds are OK expressions
22110 Analyze_And_Resolve (Lo, Any_Integer);
22111 Analyze_And_Resolve (Hi, Any_Integer);
22117 Hi := Type_High_Bound (Standard_Long_Long_Integer);
22118 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
22121 -- Find type to derive from
22123 Lo_Val := Expr_Value (Lo);
22124 Hi_Val := Expr_Value (Hi);
22126 if Can_Derive_From (Standard_Short_Short_Integer) then
22127 Base_Typ := Base_Type (Standard_Short_Short_Integer);
22129 elsif Can_Derive_From (Standard_Short_Integer) then
22130 Base_Typ := Base_Type (Standard_Short_Integer);
22132 elsif Can_Derive_From (Standard_Integer) then
22133 Base_Typ := Base_Type (Standard_Integer);
22135 elsif Can_Derive_From (Standard_Long_Integer) then
22136 Base_Typ := Base_Type (Standard_Long_Integer);
22138 elsif Can_Derive_From (Standard_Long_Long_Integer) then
22139 Check_Restriction (No_Long_Long_Integers, Def);
22140 Base_Typ := Base_Type (Standard_Long_Long_Integer);
22143 Base_Typ := Base_Type (Standard_Long_Long_Integer);
22144 Error_Msg_N ("integer type definition bounds out of range", Def);
22145 Hi := Type_High_Bound (Standard_Long_Long_Integer);
22146 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
22150 -- Complete both implicit base and declared first subtype entities. The
22151 -- inheritance of the rep item chain ensures that SPARK-related pragmas
22152 -- are not clobbered when the signed integer type acts as a full view of
22155 Set_Etype (Implicit_Base, Base_Typ);
22156 Set_Size_Info (Implicit_Base, Base_Typ);
22157 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
22158 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
22159 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
22161 Set_Ekind (T, E_Signed_Integer_Subtype);
22162 Set_Etype (T, Implicit_Base);
22163 Set_Size_Info (T, Implicit_Base);
22164 Inherit_Rep_Item_Chain (T, Implicit_Base);
22165 Set_Scalar_Range (T, Def);
22166 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
22167 Set_Is_Constrained (T);
22168 end Signed_Integer_Type_Declaration;