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 when N_Enumeration_Type_Definition =>
3138 Enumeration_Type_Declaration (T, Def);
3140 when N_Floating_Point_Definition =>
3141 Floating_Point_Type_Declaration (T, Def);
3143 when N_Decimal_Fixed_Point_Definition =>
3144 Decimal_Fixed_Point_Type_Declaration (T, Def);
3146 when N_Ordinary_Fixed_Point_Definition =>
3147 Ordinary_Fixed_Point_Type_Declaration (T, Def);
3149 when N_Signed_Integer_Type_Definition =>
3150 Signed_Integer_Type_Declaration (T, Def);
3152 when N_Modular_Type_Definition =>
3153 Modular_Type_Declaration (T, Def);
3155 when N_Record_Definition =>
3156 Record_Type_Declaration (T, N, Prev);
3158 -- If declaration has a parse error, nothing to elaborate.
3164 raise Program_Error;
3168 if Etype (T) = Any_Type then
3172 -- Controlled type is not allowed in SPARK
3174 if Is_Visibly_Controlled (T) then
3175 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
3178 -- Some common processing for all types
3180 Set_Depends_On_Private (T, Has_Private_Component (T));
3181 Check_Ops_From_Incomplete_Type;
3183 -- Both the declared entity, and its anonymous base type if one was
3184 -- created, need freeze nodes allocated.
3187 B : constant Entity_Id := Base_Type (T);
3190 -- In the case where the base type differs from the first subtype, we
3191 -- pre-allocate a freeze node, and set the proper link to the first
3192 -- subtype. Freeze_Entity will use this preallocated freeze node when
3193 -- it freezes the entity.
3195 -- This does not apply if the base type is a generic type, whose
3196 -- declaration is independent of the current derived definition.
3198 if B /= T and then not Is_Generic_Type (B) then
3199 Ensure_Freeze_Node (B);
3200 Set_First_Subtype_Link (Freeze_Node (B), T);
3203 -- A type that is imported through a limited_with clause cannot
3204 -- generate any code, and thus need not be frozen. However, an access
3205 -- type with an imported designated type needs a finalization list,
3206 -- which may be referenced in some other package that has non-limited
3207 -- visibility on the designated type. Thus we must create the
3208 -- finalization list at the point the access type is frozen, to
3209 -- prevent unsatisfied references at link time.
3211 if not From_Limited_With (T) or else Is_Access_Type (T) then
3212 Set_Has_Delayed_Freeze (T);
3216 -- Case where T is the full declaration of some private type which has
3217 -- been swapped in Defining_Identifier (N).
3219 if T /= Def_Id and then Is_Private_Type (Def_Id) then
3220 Process_Full_View (N, T, Def_Id);
3222 -- Record the reference. The form of this is a little strange, since
3223 -- the full declaration has been swapped in. So the first parameter
3224 -- here represents the entity to which a reference is made which is
3225 -- the "real" entity, i.e. the one swapped in, and the second
3226 -- parameter provides the reference location.
3228 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
3229 -- since we don't want a complaint about the full type being an
3230 -- unwanted reference to the private type
3233 B : constant Boolean := Has_Pragma_Unreferenced (T);
3235 Set_Has_Pragma_Unreferenced (T, False);
3236 Generate_Reference (T, T, 'c');
3237 Set_Has_Pragma_Unreferenced (T, B);
3240 Set_Completion_Referenced (Def_Id);
3242 -- For completion of incomplete type, process incomplete dependents
3243 -- and always mark the full type as referenced (it is the incomplete
3244 -- type that we get for any real reference).
3246 elsif Ekind (Prev) = E_Incomplete_Type then
3247 Process_Incomplete_Dependents (N, T, Prev);
3248 Generate_Reference (Prev, Def_Id, 'c');
3249 Set_Completion_Referenced (Def_Id);
3251 -- If not private type or incomplete type completion, this is a real
3252 -- definition of a new entity, so record it.
3255 Generate_Definition (Def_Id);
3258 -- Propagate any pending access types whose finalization masters need to
3259 -- be fully initialized from the partial to the full view. Guard against
3260 -- an illegal full view that remains unanalyzed.
3262 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
3263 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
3266 if Chars (Scope (Def_Id)) = Name_System
3267 and then Chars (Def_Id) = Name_Address
3268 and then In_Predefined_Unit (N)
3270 Set_Is_Descendant_Of_Address (Def_Id);
3271 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
3272 Set_Is_Descendant_Of_Address (Prev);
3275 Set_Optimize_Alignment_Flags (Def_Id);
3276 Check_Eliminated (Def_Id);
3278 -- If the declaration is a completion and aspects are present, apply
3279 -- them to the entity for the type which is currently the partial
3280 -- view, but which is the one that will be frozen.
3282 if Has_Aspects (N) then
3284 -- In most cases the partial view is a private type, and both views
3285 -- appear in different declarative parts. In the unusual case where
3286 -- the partial view is incomplete, perform the analysis on the
3287 -- full view, to prevent freezing anomalies with the corresponding
3288 -- class-wide type, which otherwise might be frozen before the
3289 -- dispatch table is built.
3292 and then Ekind (Prev) /= E_Incomplete_Type
3294 Analyze_Aspect_Specifications (N, Prev);
3299 Analyze_Aspect_Specifications (N, Def_Id);
3303 if Is_Derived_Type (Prev)
3304 and then Def_Id /= Prev
3306 Check_Nonoverridable_Aspects;
3308 end Analyze_Full_Type_Declaration;
3310 ----------------------------------
3311 -- Analyze_Incomplete_Type_Decl --
3312 ----------------------------------
3314 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3315 F : constant Boolean := Is_Pure (Current_Scope);
3319 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3321 Generate_Definition (Defining_Identifier (N));
3323 -- Process an incomplete declaration. The identifier must not have been
3324 -- declared already in the scope. However, an incomplete declaration may
3325 -- appear in the private part of a package, for a private type that has
3326 -- already been declared.
3328 -- In this case, the discriminants (if any) must match
3330 T := Find_Type_Name (N);
3332 Set_Ekind (T, E_Incomplete_Type);
3333 Init_Size_Align (T);
3334 Set_Is_First_Subtype (T, True);
3337 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3338 -- incomplete types.
3340 if Tagged_Present (N) then
3341 Set_Is_Tagged_Type (T, True);
3342 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3343 Make_Class_Wide_Type (T);
3344 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3347 Set_Stored_Constraint (T, No_Elist);
3349 if Present (Discriminant_Specifications (N)) then
3351 Process_Discriminants (N);
3355 -- If the type has discriminants, nontrivial subtypes may be declared
3356 -- before the full view of the type. The full views of those subtypes
3357 -- will be built after the full view of the type.
3359 Set_Private_Dependents (T, New_Elmt_List);
3361 end Analyze_Incomplete_Type_Decl;
3363 -----------------------------------
3364 -- Analyze_Interface_Declaration --
3365 -----------------------------------
3367 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3368 CW : constant Entity_Id := Class_Wide_Type (T);
3371 Set_Is_Tagged_Type (T);
3372 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3374 Set_Is_Limited_Record (T, Limited_Present (Def)
3375 or else Task_Present (Def)
3376 or else Protected_Present (Def)
3377 or else Synchronized_Present (Def));
3379 -- Type is abstract if full declaration carries keyword, or if previous
3380 -- partial view did.
3382 Set_Is_Abstract_Type (T);
3383 Set_Is_Interface (T);
3385 -- Type is a limited interface if it includes the keyword limited, task,
3386 -- protected, or synchronized.
3388 Set_Is_Limited_Interface
3389 (T, Limited_Present (Def)
3390 or else Protected_Present (Def)
3391 or else Synchronized_Present (Def)
3392 or else Task_Present (Def));
3394 Set_Interfaces (T, New_Elmt_List);
3395 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3397 -- Complete the decoration of the class-wide entity if it was already
3398 -- built (i.e. during the creation of the limited view)
3400 if Present (CW) then
3401 Set_Is_Interface (CW);
3402 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3405 -- Check runtime support for synchronized interfaces
3407 if (Is_Task_Interface (T)
3408 or else Is_Protected_Interface (T)
3409 or else Is_Synchronized_Interface (T))
3410 and then not RTE_Available (RE_Select_Specific_Data)
3412 Error_Msg_CRT ("synchronized interfaces", T);
3414 end Analyze_Interface_Declaration;
3416 -----------------------------
3417 -- Analyze_Itype_Reference --
3418 -----------------------------
3420 -- Nothing to do. This node is placed in the tree only for the benefit of
3421 -- back end processing, and has no effect on the semantic processing.
3423 procedure Analyze_Itype_Reference (N : Node_Id) is
3425 pragma Assert (Is_Itype (Itype (N)));
3427 end Analyze_Itype_Reference;
3429 --------------------------------
3430 -- Analyze_Number_Declaration --
3431 --------------------------------
3433 procedure Analyze_Number_Declaration (N : Node_Id) is
3434 E : constant Node_Id := Expression (N);
3435 Id : constant Entity_Id := Defining_Identifier (N);
3436 Index : Interp_Index;
3441 Generate_Definition (Id);
3444 -- This is an optimization of a common case of an integer literal
3446 if Nkind (E) = N_Integer_Literal then
3447 Set_Is_Static_Expression (E, True);
3448 Set_Etype (E, Universal_Integer);
3450 Set_Etype (Id, Universal_Integer);
3451 Set_Ekind (Id, E_Named_Integer);
3452 Set_Is_Frozen (Id, True);
3456 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3458 -- Process expression, replacing error by integer zero, to avoid
3459 -- cascaded errors or aborts further along in the processing
3461 -- Replace Error by integer zero, which seems least likely to cause
3465 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3466 Set_Error_Posted (E);
3471 -- Verify that the expression is static and numeric. If
3472 -- the expression is overloaded, we apply the preference
3473 -- rule that favors root numeric types.
3475 if not Is_Overloaded (E) then
3477 if Has_Dynamic_Predicate_Aspect (T) then
3479 ("subtype has dynamic predicate, "
3480 & "not allowed in number declaration", N);
3486 Get_First_Interp (E, Index, It);
3487 while Present (It.Typ) loop
3488 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3489 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3491 if T = Any_Type then
3494 elsif It.Typ = Universal_Real
3496 It.Typ = Universal_Integer
3498 -- Choose universal interpretation over any other
3505 Get_Next_Interp (Index, It);
3509 if Is_Integer_Type (T) then
3511 Set_Etype (Id, Universal_Integer);
3512 Set_Ekind (Id, E_Named_Integer);
3514 elsif Is_Real_Type (T) then
3516 -- Because the real value is converted to universal_real, this is a
3517 -- legal context for a universal fixed expression.
3519 if T = Universal_Fixed then
3521 Loc : constant Source_Ptr := Sloc (N);
3522 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3524 New_Occurrence_Of (Universal_Real, Loc),
3525 Expression => Relocate_Node (E));
3532 elsif T = Any_Fixed then
3533 Error_Msg_N ("illegal context for mixed mode operation", E);
3535 -- Expression is of the form : universal_fixed * integer. Try to
3536 -- resolve as universal_real.
3538 T := Universal_Real;
3543 Set_Etype (Id, Universal_Real);
3544 Set_Ekind (Id, E_Named_Real);
3547 Wrong_Type (E, Any_Numeric);
3551 Set_Ekind (Id, E_Constant);
3552 Set_Never_Set_In_Source (Id, True);
3553 Set_Is_True_Constant (Id, True);
3557 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3558 Set_Etype (E, Etype (Id));
3561 if not Is_OK_Static_Expression (E) then
3562 Flag_Non_Static_Expr
3563 ("non-static expression used in number declaration!", E);
3564 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3565 Set_Etype (E, Any_Type);
3568 Analyze_Dimension (N);
3569 end Analyze_Number_Declaration;
3571 --------------------------------
3572 -- Analyze_Object_Declaration --
3573 --------------------------------
3575 -- WARNING: This routine manages Ghost regions. Return statements must be
3576 -- replaced by gotos which jump to the end of the routine and restore the
3579 procedure Analyze_Object_Declaration (N : Node_Id) is
3580 Loc : constant Source_Ptr := Sloc (N);
3581 Id : constant Entity_Id := Defining_Identifier (N);
3585 E : Node_Id := Expression (N);
3586 -- E is set to Expression (N) throughout this routine. When
3587 -- Expression (N) is modified, E is changed accordingly.
3589 Prev_Entity : Entity_Id := Empty;
3591 function Count_Tasks (T : Entity_Id) return Uint;
3592 -- This function is called when a non-generic library level object of a
3593 -- task type is declared. Its function is to count the static number of
3594 -- tasks declared within the type (it is only called if Has_Task is set
3595 -- for T). As a side effect, if an array of tasks with non-static bounds
3596 -- or a variant record type is encountered, Check_Restriction is called
3597 -- indicating the count is unknown.
3599 function Delayed_Aspect_Present return Boolean;
3600 -- If the declaration has an expression that is an aggregate, and it
3601 -- has aspects that require delayed analysis, the resolution of the
3602 -- aggregate must be deferred to the freeze point of the objet. This
3603 -- special processing was created for address clauses, but it must
3604 -- also apply to Alignment. This must be done before the aspect
3605 -- specifications are analyzed because we must handle the aggregate
3606 -- before the analysis of the object declaration is complete.
3608 -- Any other relevant delayed aspects on object declarations ???
3614 function Count_Tasks (T : Entity_Id) return Uint is
3620 if Is_Task_Type (T) then
3623 elsif Is_Record_Type (T) then
3624 if Has_Discriminants (T) then
3625 Check_Restriction (Max_Tasks, N);
3630 C := First_Component (T);
3631 while Present (C) loop
3632 V := V + Count_Tasks (Etype (C));
3639 elsif Is_Array_Type (T) then
3640 X := First_Index (T);
3641 V := Count_Tasks (Component_Type (T));
3642 while Present (X) loop
3645 if not Is_OK_Static_Subtype (C) then
3646 Check_Restriction (Max_Tasks, N);
3649 V := V * (UI_Max (Uint_0,
3650 Expr_Value (Type_High_Bound (C)) -
3651 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3664 ----------------------------
3665 -- Delayed_Aspect_Present --
3666 ----------------------------
3668 function Delayed_Aspect_Present return Boolean is
3673 if Present (Aspect_Specifications (N)) then
3674 A := First (Aspect_Specifications (N));
3675 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3676 while Present (A) loop
3677 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3686 end Delayed_Aspect_Present;
3690 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
3691 -- Save the Ghost mode to restore on exit
3693 Related_Id : Entity_Id;
3695 -- Start of processing for Analyze_Object_Declaration
3698 -- There are three kinds of implicit types generated by an
3699 -- object declaration:
3701 -- 1. Those generated by the original Object Definition
3703 -- 2. Those generated by the Expression
3705 -- 3. Those used to constrain the Object Definition with the
3706 -- expression constraints when the definition is unconstrained.
3708 -- They must be generated in this order to avoid order of elaboration
3709 -- issues. Thus the first step (after entering the name) is to analyze
3710 -- the object definition.
3712 if Constant_Present (N) then
3713 Prev_Entity := Current_Entity_In_Scope (Id);
3715 if Present (Prev_Entity)
3717 -- If the homograph is an implicit subprogram, it is overridden
3718 -- by the current declaration.
3720 ((Is_Overloadable (Prev_Entity)
3721 and then Is_Inherited_Operation (Prev_Entity))
3723 -- The current object is a discriminal generated for an entry
3724 -- family index. Even though the index is a constant, in this
3725 -- particular context there is no true constant redeclaration.
3726 -- Enter_Name will handle the visibility.
3729 (Is_Discriminal (Id)
3730 and then Ekind (Discriminal_Link (Id)) =
3731 E_Entry_Index_Parameter)
3733 -- The current object is the renaming for a generic declared
3734 -- within the instance.
3737 (Ekind (Prev_Entity) = E_Package
3738 and then Nkind (Parent (Prev_Entity)) =
3739 N_Package_Renaming_Declaration
3740 and then not Comes_From_Source (Prev_Entity)
3742 Is_Generic_Instance (Renamed_Entity (Prev_Entity)))
3744 -- The entity may be a homonym of a private component of the
3745 -- enclosing protected object, for which we create a local
3746 -- renaming declaration. The declaration is legal, even if
3747 -- useless when it just captures that component.
3750 (Ekind (Scope (Current_Scope)) = E_Protected_Type
3751 and then Nkind (Parent (Prev_Entity)) =
3752 N_Object_Renaming_Declaration))
3754 Prev_Entity := Empty;
3758 if Present (Prev_Entity) then
3760 -- The object declaration is Ghost when it completes a deferred Ghost
3763 Mark_And_Set_Ghost_Completion (N, Prev_Entity);
3765 Constant_Redeclaration (Id, N, T);
3767 Generate_Reference (Prev_Entity, Id, 'c');
3768 Set_Completion_Referenced (Id);
3770 if Error_Posted (N) then
3772 -- Type mismatch or illegal redeclaration; do not analyze
3773 -- expression to avoid cascaded errors.
3775 T := Find_Type_Of_Object (Object_Definition (N), N);
3777 Set_Ekind (Id, E_Variable);
3781 -- In the normal case, enter identifier at the start to catch premature
3782 -- usage in the initialization expression.
3785 Generate_Definition (Id);
3788 Mark_Coextensions (N, Object_Definition (N));
3790 T := Find_Type_Of_Object (Object_Definition (N), N);
3792 if Nkind (Object_Definition (N)) = N_Access_Definition
3794 (Access_To_Subprogram_Definition (Object_Definition (N)))
3795 and then Protected_Present
3796 (Access_To_Subprogram_Definition (Object_Definition (N)))
3798 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3801 if Error_Posted (Id) then
3803 Set_Ekind (Id, E_Variable);
3808 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3809 -- out some static checks.
3811 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3813 -- In case of aggregates we must also take care of the correct
3814 -- initialization of nested aggregates bug this is done at the
3815 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
3817 if Present (Expression (N))
3818 and then Nkind (Expression (N)) = N_Aggregate
3824 Save_Typ : constant Entity_Id := Etype (Id);
3826 Set_Etype (Id, T); -- Temp. decoration for static checks
3827 Null_Exclusion_Static_Checks (N);
3828 Set_Etype (Id, Save_Typ);
3833 -- Object is marked pure if it is in a pure scope
3835 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3837 -- If deferred constant, make sure context is appropriate. We detect
3838 -- a deferred constant as a constant declaration with no expression.
3839 -- A deferred constant can appear in a package body if its completion
3840 -- is by means of an interface pragma.
3842 if Constant_Present (N) and then No (E) then
3844 -- A deferred constant may appear in the declarative part of the
3845 -- following constructs:
3849 -- extended return statements
3852 -- subprogram bodies
3855 -- When declared inside a package spec, a deferred constant must be
3856 -- completed by a full constant declaration or pragma Import. In all
3857 -- other cases, the only proper completion is pragma Import. Extended
3858 -- return statements are flagged as invalid contexts because they do
3859 -- not have a declarative part and so cannot accommodate the pragma.
3861 if Ekind (Current_Scope) = E_Return_Statement then
3863 ("invalid context for deferred constant declaration (RM 7.4)",
3866 ("\declaration requires an initialization expression",
3868 Set_Constant_Present (N, False);
3870 -- In Ada 83, deferred constant must be of private type
3872 elsif not Is_Private_Type (T) then
3873 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3875 ("(Ada 83) deferred constant must be private type", N);
3879 -- If not a deferred constant, then the object declaration freezes
3880 -- its type, unless the object is of an anonymous type and has delayed
3881 -- aspects. In that case the type is frozen when the object itself is.
3884 Check_Fully_Declared (T, N);
3886 if Has_Delayed_Aspects (Id)
3887 and then Is_Array_Type (T)
3888 and then Is_Itype (T)
3890 Set_Has_Delayed_Freeze (T);
3892 Freeze_Before (N, T);
3896 -- If the object was created by a constrained array definition, then
3897 -- set the link in both the anonymous base type and anonymous subtype
3898 -- that are built to represent the array type to point to the object.
3900 if Nkind (Object_Definition (Declaration_Node (Id))) =
3901 N_Constrained_Array_Definition
3903 Set_Related_Array_Object (T, Id);
3904 Set_Related_Array_Object (Base_Type (T), Id);
3907 -- Special checks for protected objects not at library level
3909 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
3910 Check_Restriction (No_Local_Protected_Objects, Id);
3912 -- Protected objects with interrupt handlers must be at library level
3914 -- Ada 2005: This test is not needed (and the corresponding clause
3915 -- in the RM is removed) because accessibility checks are sufficient
3916 -- to make handlers not at the library level illegal.
3918 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3919 -- applies to the '95 version of the language as well.
3921 if Is_Protected_Type (T)
3922 and then Has_Interrupt_Handler (T)
3923 and then Ada_Version < Ada_95
3926 ("interrupt object can only be declared at library level", Id);
3930 -- Check for violation of No_Local_Timing_Events
3932 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
3933 Check_Restriction (No_Local_Timing_Events, Id);
3936 -- The actual subtype of the object is the nominal subtype, unless
3937 -- the nominal one is unconstrained and obtained from the expression.
3941 -- These checks should be performed before the initialization expression
3942 -- is considered, so that the Object_Definition node is still the same
3943 -- as in source code.
3945 -- In SPARK, the nominal subtype is always given by a subtype mark
3946 -- and must not be unconstrained. (The only exception to this is the
3947 -- acceptance of declarations of constants of type String.)
3949 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3951 Check_SPARK_05_Restriction
3952 ("subtype mark required", Object_Definition (N));
3954 elsif Is_Array_Type (T)
3955 and then not Is_Constrained (T)
3956 and then T /= Standard_String
3958 Check_SPARK_05_Restriction
3959 ("subtype mark of constrained type expected",
3960 Object_Definition (N));
3963 -- There are no aliased objects in SPARK
3965 if Aliased_Present (N) then
3966 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3969 -- Process initialization expression if present and not in error
3971 if Present (E) and then E /= Error then
3973 -- Generate an error in case of CPP class-wide object initialization.
3974 -- Required because otherwise the expansion of the class-wide
3975 -- assignment would try to use 'size to initialize the object
3976 -- (primitive that is not available in CPP tagged types).
3978 if Is_Class_Wide_Type (Act_T)
3980 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3982 (Present (Full_View (Root_Type (Etype (Act_T))))
3984 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3987 ("predefined assignment not available for 'C'P'P tagged types",
3991 Mark_Coextensions (N, E);
3994 -- In case of errors detected in the analysis of the expression,
3995 -- decorate it with the expected type to avoid cascaded errors
3997 if No (Etype (E)) then
4001 -- If an initialization expression is present, then we set the
4002 -- Is_True_Constant flag. It will be reset if this is a variable
4003 -- and it is indeed modified.
4005 Set_Is_True_Constant (Id, True);
4007 -- If we are analyzing a constant declaration, set its completion
4008 -- flag after analyzing and resolving the expression.
4010 if Constant_Present (N) then
4011 Set_Has_Completion (Id);
4014 -- Set type and resolve (type may be overridden later on). Note:
4015 -- Ekind (Id) must still be E_Void at this point so that incorrect
4016 -- early usage within E is properly diagnosed.
4020 -- If the expression is an aggregate we must look ahead to detect
4021 -- the possible presence of an address clause, and defer resolution
4022 -- and expansion of the aggregate to the freeze point of the entity.
4024 -- This is not always legal because the aggregate may contain other
4025 -- references that need freezing, e.g. references to other entities
4026 -- with address clauses. In any case, when compiling with -gnatI the
4027 -- presence of the address clause must be ignored.
4029 if Comes_From_Source (N)
4030 and then Expander_Active
4031 and then Nkind (E) = N_Aggregate
4033 ((Present (Following_Address_Clause (N))
4034 and then not Ignore_Rep_Clauses)
4035 or else Delayed_Aspect_Present)
4043 -- No further action needed if E is a call to an inlined function
4044 -- which returns an unconstrained type and it has been expanded into
4045 -- a procedure call. In that case N has been replaced by an object
4046 -- declaration without initializing expression and it has been
4047 -- analyzed (see Expand_Inlined_Call).
4049 if Back_End_Inlining
4050 and then Expander_Active
4051 and then Nkind (E) = N_Function_Call
4052 and then Nkind (Name (E)) in N_Has_Entity
4053 and then Is_Inlined (Entity (Name (E)))
4054 and then not Is_Constrained (Etype (E))
4055 and then Analyzed (N)
4056 and then No (Expression (N))
4061 -- If E is null and has been replaced by an N_Raise_Constraint_Error
4062 -- node (which was marked already-analyzed), we need to set the type
4063 -- to something other than Any_Access in order to keep gigi happy.
4065 if Etype (E) = Any_Access then
4069 -- If the object is an access to variable, the initialization
4070 -- expression cannot be an access to constant.
4072 if Is_Access_Type (T)
4073 and then not Is_Access_Constant (T)
4074 and then Is_Access_Type (Etype (E))
4075 and then Is_Access_Constant (Etype (E))
4078 ("access to variable cannot be initialized with an "
4079 & "access-to-constant expression", E);
4082 if not Assignment_OK (N) then
4083 Check_Initialization (T, E);
4086 Check_Unset_Reference (E);
4088 -- If this is a variable, then set current value. If this is a
4089 -- declared constant of a scalar type with a static expression,
4090 -- indicate that it is always valid.
4092 if not Constant_Present (N) then
4093 if Compile_Time_Known_Value (E) then
4094 Set_Current_Value (Id, E);
4097 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
4098 Set_Is_Known_Valid (Id);
4101 -- Deal with setting of null flags
4103 if Is_Access_Type (T) then
4104 if Known_Non_Null (E) then
4105 Set_Is_Known_Non_Null (Id, True);
4106 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
4107 Set_Is_Known_Null (Id, True);
4111 -- Check incorrect use of dynamically tagged expressions
4113 if Is_Tagged_Type (T) then
4114 Check_Dynamically_Tagged_Expression
4120 Apply_Scalar_Range_Check (E, T);
4121 Apply_Static_Length_Check (E, T);
4123 if Nkind (Original_Node (N)) = N_Object_Declaration
4124 and then Comes_From_Source (Original_Node (N))
4126 -- Only call test if needed
4128 and then Restriction_Check_Required (SPARK_05)
4129 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
4131 Check_SPARK_05_Restriction
4132 ("initialization expression is not appropriate", E);
4135 -- A formal parameter of a specific tagged type whose related
4136 -- subprogram is subject to pragma Extensions_Visible with value
4137 -- "False" cannot be implicitly converted to a class-wide type by
4138 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
4139 -- not consider internally generated expressions.
4141 if Is_Class_Wide_Type (T)
4142 and then Comes_From_Source (E)
4143 and then Is_EVF_Expression (E)
4146 ("formal parameter cannot be implicitly converted to "
4147 & "class-wide type when Extensions_Visible is False", E);
4151 -- If the No_Streams restriction is set, check that the type of the
4152 -- object is not, and does not contain, any subtype derived from
4153 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
4154 -- Has_Stream just for efficiency reasons. There is no point in
4155 -- spending time on a Has_Stream check if the restriction is not set.
4157 if Restriction_Check_Required (No_Streams) then
4158 if Has_Stream (T) then
4159 Check_Restriction (No_Streams, N);
4163 -- Deal with predicate check before we start to do major rewriting. It
4164 -- is OK to initialize and then check the initialized value, since the
4165 -- object goes out of scope if we get a predicate failure. Note that we
4166 -- do this in the analyzer and not the expander because the analyzer
4167 -- does some substantial rewriting in some cases.
4169 -- We need a predicate check if the type has predicates that are not
4170 -- ignored, and if either there is an initializing expression, or for
4171 -- default initialization when we have at least one case of an explicit
4172 -- default initial value and then this is not an internal declaration
4173 -- whose initialization comes later (as for an aggregate expansion).
4175 if not Suppress_Assignment_Checks (N)
4176 and then Present (Predicate_Function (T))
4177 and then not Predicates_Ignored (T)
4178 and then not No_Initialization (N)
4182 Is_Partially_Initialized_Type (T, Include_Implicit => False))
4184 -- If the type has a static predicate and the expression is known at
4185 -- compile time, see if the expression satisfies the predicate.
4188 Check_Expression_Against_Static_Predicate (E, T);
4191 -- If the type is a null record and there is no explicit initial
4192 -- expression, no predicate check applies.
4194 if No (E) and then Is_Null_Record_Type (T) then
4197 -- Do not generate a predicate check if the initialization expression
4198 -- is a type conversion because the conversion has been subjected to
4199 -- the same check. This is a small optimization which avoid redundant
4202 elsif Present (E) and then Nkind (E) = N_Type_Conversion then
4207 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
4211 -- Case of unconstrained type
4213 if not Is_Definite_Subtype (T) then
4215 -- In SPARK, a declaration of unconstrained type is allowed
4216 -- only for constants of type string.
4218 if Is_String_Type (T) and then not Constant_Present (N) then
4219 Check_SPARK_05_Restriction
4220 ("declaration of object of unconstrained type not allowed", N);
4223 -- Nothing to do in deferred constant case
4225 if Constant_Present (N) and then No (E) then
4228 -- Case of no initialization present
4231 if No_Initialization (N) then
4234 elsif Is_Class_Wide_Type (T) then
4236 ("initialization required in class-wide declaration ", N);
4240 ("unconstrained subtype not allowed (need initialization)",
4241 Object_Definition (N));
4243 if Is_Record_Type (T) and then Has_Discriminants (T) then
4245 ("\provide initial value or explicit discriminant values",
4246 Object_Definition (N));
4249 ("\or give default discriminant values for type&",
4250 Object_Definition (N), T);
4252 elsif Is_Array_Type (T) then
4254 ("\provide initial value or explicit array bounds",
4255 Object_Definition (N));
4259 -- Case of initialization present but in error. Set initial
4260 -- expression as absent (but do not make above complaints)
4262 elsif E = Error then
4263 Set_Expression (N, Empty);
4266 -- Case of initialization present
4269 -- Check restrictions in Ada 83
4271 if not Constant_Present (N) then
4273 -- Unconstrained variables not allowed in Ada 83 mode
4275 if Ada_Version = Ada_83
4276 and then Comes_From_Source (Object_Definition (N))
4279 ("(Ada 83) unconstrained variable not allowed",
4280 Object_Definition (N));
4284 -- Now we constrain the variable from the initializing expression
4286 -- If the expression is an aggregate, it has been expanded into
4287 -- individual assignments. Retrieve the actual type from the
4288 -- expanded construct.
4290 if Is_Array_Type (T)
4291 and then No_Initialization (N)
4292 and then Nkind (Original_Node (E)) = N_Aggregate
4296 -- In case of class-wide interface object declarations we delay
4297 -- the generation of the equivalent record type declarations until
4298 -- its expansion because there are cases in they are not required.
4300 elsif Is_Interface (T) then
4303 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4304 -- we should prevent the generation of another Itype with the
4305 -- same name as the one already generated, or we end up with
4306 -- two identical types in GNATprove.
4308 elsif GNATprove_Mode then
4311 -- If the type is an unchecked union, no subtype can be built from
4312 -- the expression. Rewrite declaration as a renaming, which the
4313 -- back-end can handle properly. This is a rather unusual case,
4314 -- because most unchecked_union declarations have default values
4315 -- for discriminants and are thus not indefinite.
4317 elsif Is_Unchecked_Union (T) then
4318 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4319 Set_Ekind (Id, E_Constant);
4321 Set_Ekind (Id, E_Variable);
4325 Make_Object_Renaming_Declaration (Loc,
4326 Defining_Identifier => Id,
4327 Subtype_Mark => New_Occurrence_Of (T, Loc),
4330 Set_Renamed_Object (Id, E);
4331 Freeze_Before (N, T);
4336 -- Ensure that the generated subtype has a unique external name
4337 -- when the related object is public. This guarantees that the
4338 -- subtype and its bounds will not be affected by switches or
4339 -- pragmas that may offset the internal counter due to extra
4342 if Is_Public (Id) then
4345 Related_Id := Empty;
4348 Expand_Subtype_From_Expr
4351 Subtype_Indic => Object_Definition (N),
4353 Related_Id => Related_Id);
4355 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4358 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4360 if Aliased_Present (N) then
4361 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4364 Freeze_Before (N, Act_T);
4365 Freeze_Before (N, T);
4368 elsif Is_Array_Type (T)
4369 and then No_Initialization (N)
4370 and then (Nkind (Original_Node (E)) = N_Aggregate
4371 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4372 and then Nkind (Original_Node (Expression
4373 (Original_Node (E)))) = N_Aggregate))
4375 if not Is_Entity_Name (Object_Definition (N)) then
4377 Check_Compile_Time_Size (Act_T);
4379 if Aliased_Present (N) then
4380 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4384 -- When the given object definition and the aggregate are specified
4385 -- independently, and their lengths might differ do a length check.
4386 -- This cannot happen if the aggregate is of the form (others =>...)
4388 if not Is_Constrained (T) then
4391 elsif Nkind (E) = N_Raise_Constraint_Error then
4393 -- Aggregate is statically illegal. Place back in declaration
4395 Set_Expression (N, E);
4396 Set_No_Initialization (N, False);
4398 elsif T = Etype (E) then
4401 elsif Nkind (E) = N_Aggregate
4402 and then Present (Component_Associations (E))
4403 and then Present (Choice_List (First (Component_Associations (E))))
4405 Nkind (First (Choice_List (First (Component_Associations (E))))) =
4411 Apply_Length_Check (E, T);
4414 -- If the type is limited unconstrained with defaulted discriminants and
4415 -- there is no expression, then the object is constrained by the
4416 -- defaults, so it is worthwhile building the corresponding subtype.
4418 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4419 and then not Is_Constrained (T)
4420 and then Has_Discriminants (T)
4423 Act_T := Build_Default_Subtype (T, N);
4425 -- Ada 2005: A limited object may be initialized by means of an
4426 -- aggregate. If the type has default discriminants it has an
4427 -- unconstrained nominal type, Its actual subtype will be obtained
4428 -- from the aggregate, and not from the default discriminants.
4433 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4435 elsif Nkind (E) = N_Function_Call
4436 and then Constant_Present (N)
4437 and then Has_Unconstrained_Elements (Etype (E))
4439 -- The back-end has problems with constants of a discriminated type
4440 -- with defaults, if the initial value is a function call. We
4441 -- generate an intermediate temporary that will receive a reference
4442 -- to the result of the call. The initialization expression then
4443 -- becomes a dereference of that temporary.
4445 Remove_Side_Effects (E);
4447 -- If this is a constant declaration of an unconstrained type and
4448 -- the initialization is an aggregate, we can use the subtype of the
4449 -- aggregate for the declared entity because it is immutable.
4451 elsif not Is_Constrained (T)
4452 and then Has_Discriminants (T)
4453 and then Constant_Present (N)
4454 and then not Has_Unchecked_Union (T)
4455 and then Nkind (E) = N_Aggregate
4460 -- Check No_Wide_Characters restriction
4462 Check_Wide_Character_Restriction (T, Object_Definition (N));
4464 -- Indicate this is not set in source. Certainly true for constants, and
4465 -- true for variables so far (will be reset for a variable if and when
4466 -- we encounter a modification in the source).
4468 Set_Never_Set_In_Source (Id);
4470 -- Now establish the proper kind and type of the object
4472 if Constant_Present (N) then
4473 Set_Ekind (Id, E_Constant);
4474 Set_Is_True_Constant (Id);
4477 Set_Ekind (Id, E_Variable);
4479 -- A variable is set as shared passive if it appears in a shared
4480 -- passive package, and is at the outer level. This is not done for
4481 -- entities generated during expansion, because those are always
4482 -- manipulated locally.
4484 if Is_Shared_Passive (Current_Scope)
4485 and then Is_Library_Level_Entity (Id)
4486 and then Comes_From_Source (Id)
4488 Set_Is_Shared_Passive (Id);
4489 Check_Shared_Var (Id, T, N);
4492 -- Set Has_Initial_Value if initializing expression present. Note
4493 -- that if there is no initializing expression, we leave the state
4494 -- of this flag unchanged (usually it will be False, but notably in
4495 -- the case of exception choice variables, it will already be true).
4498 Set_Has_Initial_Value (Id);
4502 -- Initialize alignment and size and capture alignment setting
4504 Init_Alignment (Id);
4506 Set_Optimize_Alignment_Flags (Id);
4508 -- Deal with aliased case
4510 if Aliased_Present (N) then
4511 Set_Is_Aliased (Id);
4513 -- If the object is aliased and the type is unconstrained with
4514 -- defaulted discriminants and there is no expression, then the
4515 -- object is constrained by the defaults, so it is worthwhile
4516 -- building the corresponding subtype.
4518 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4519 -- unconstrained, then only establish an actual subtype if the
4520 -- nominal subtype is indefinite. In definite cases the object is
4521 -- unconstrained in Ada 2005.
4524 and then Is_Record_Type (T)
4525 and then not Is_Constrained (T)
4526 and then Has_Discriminants (T)
4527 and then (Ada_Version < Ada_2005
4528 or else not Is_Definite_Subtype (T))
4530 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4534 -- Now we can set the type of the object
4536 Set_Etype (Id, Act_T);
4538 -- Non-constant object is marked to be treated as volatile if type is
4539 -- volatile and we clear the Current_Value setting that may have been
4540 -- set above. Doing so for constants isn't required and might interfere
4541 -- with possible uses of the object as a static expression in contexts
4542 -- incompatible with volatility (e.g. as a case-statement alternative).
4544 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4545 Set_Treat_As_Volatile (Id);
4546 Set_Current_Value (Id, Empty);
4549 -- Deal with controlled types
4551 if Has_Controlled_Component (Etype (Id))
4552 or else Is_Controlled (Etype (Id))
4554 if not Is_Library_Level_Entity (Id) then
4555 Check_Restriction (No_Nested_Finalization, N);
4557 Validate_Controlled_Object (Id);
4561 if Has_Task (Etype (Id)) then
4562 Check_Restriction (No_Tasking, N);
4564 -- Deal with counting max tasks
4566 -- Nothing to do if inside a generic
4568 if Inside_A_Generic then
4571 -- If library level entity, then count tasks
4573 elsif Is_Library_Level_Entity (Id) then
4574 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4576 -- If not library level entity, then indicate we don't know max
4577 -- tasks and also check task hierarchy restriction and blocking
4578 -- operation (since starting a task is definitely blocking).
4581 Check_Restriction (Max_Tasks, N);
4582 Check_Restriction (No_Task_Hierarchy, N);
4583 Check_Potentially_Blocking_Operation (N);
4586 -- A rather specialized test. If we see two tasks being declared
4587 -- of the same type in the same object declaration, and the task
4588 -- has an entry with an address clause, we know that program error
4589 -- will be raised at run time since we can't have two tasks with
4590 -- entries at the same address.
4592 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4597 E := First_Entity (Etype (Id));
4598 while Present (E) loop
4599 if Ekind (E) = E_Entry
4600 and then Present (Get_Attribute_Definition_Clause
4601 (E, Attribute_Address))
4603 Error_Msg_Warn := SPARK_Mode /= On;
4605 ("more than one task with same entry address<<", N);
4606 Error_Msg_N ("\Program_Error [<<", N);
4608 Make_Raise_Program_Error (Loc,
4609 Reason => PE_Duplicated_Entry_Address));
4619 -- Some simple constant-propagation: if the expression is a constant
4620 -- string initialized with a literal, share the literal. This avoids
4624 and then Is_Entity_Name (E)
4625 and then Ekind (Entity (E)) = E_Constant
4626 and then Base_Type (Etype (E)) = Standard_String
4629 Val : constant Node_Id := Constant_Value (Entity (E));
4631 if Present (Val) and then Nkind (Val) = N_String_Literal then
4632 Rewrite (E, New_Copy (Val));
4637 -- Another optimization: if the nominal subtype is unconstrained and
4638 -- the expression is a function call that returns an unconstrained
4639 -- type, rewrite the declaration as a renaming of the result of the
4640 -- call. The exceptions below are cases where the copy is expected,
4641 -- either by the back end (Aliased case) or by the semantics, as for
4642 -- initializing controlled types or copying tags for class-wide types.
4645 and then Nkind (E) = N_Explicit_Dereference
4646 and then Nkind (Original_Node (E)) = N_Function_Call
4647 and then not Is_Library_Level_Entity (Id)
4648 and then not Is_Constrained (Underlying_Type (T))
4649 and then not Is_Aliased (Id)
4650 and then not Is_Class_Wide_Type (T)
4651 and then not Is_Controlled_Active (T)
4652 and then not Has_Controlled_Component (Base_Type (T))
4653 and then Expander_Active
4656 Make_Object_Renaming_Declaration (Loc,
4657 Defining_Identifier => Id,
4658 Access_Definition => Empty,
4659 Subtype_Mark => New_Occurrence_Of
4660 (Base_Type (Etype (Id)), Loc),
4663 Set_Renamed_Object (Id, E);
4665 -- Force generation of debugging information for the constant and for
4666 -- the renamed function call.
4668 Set_Debug_Info_Needed (Id);
4669 Set_Debug_Info_Needed (Entity (Prefix (E)));
4672 if Present (Prev_Entity)
4673 and then Is_Frozen (Prev_Entity)
4674 and then not Error_Posted (Id)
4676 Error_Msg_N ("full constant declaration appears too late", N);
4679 Check_Eliminated (Id);
4681 -- Deal with setting In_Private_Part flag if in private part
4683 if Ekind (Scope (Id)) = E_Package
4684 and then In_Private_Part (Scope (Id))
4686 Set_In_Private_Part (Id);
4690 -- Initialize the refined state of a variable here because this is a
4691 -- common destination for legal and illegal object declarations.
4693 if Ekind (Id) = E_Variable then
4694 Set_Encapsulating_State (Id, Empty);
4697 if Has_Aspects (N) then
4698 Analyze_Aspect_Specifications (N, Id);
4701 Analyze_Dimension (N);
4703 -- Verify whether the object declaration introduces an illegal hidden
4704 -- state within a package subject to a null abstract state.
4706 if Ekind (Id) = E_Variable then
4707 Check_No_Hidden_State (Id);
4710 Restore_Ghost_Mode (Saved_GM);
4711 end Analyze_Object_Declaration;
4713 ---------------------------
4714 -- Analyze_Others_Choice --
4715 ---------------------------
4717 -- Nothing to do for the others choice node itself, the semantic analysis
4718 -- of the others choice will occur as part of the processing of the parent
4720 procedure Analyze_Others_Choice (N : Node_Id) is
4721 pragma Warnings (Off, N);
4724 end Analyze_Others_Choice;
4726 -------------------------------------------
4727 -- Analyze_Private_Extension_Declaration --
4728 -------------------------------------------
4730 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4731 Indic : constant Node_Id := Subtype_Indication (N);
4732 T : constant Entity_Id := Defining_Identifier (N);
4734 Iface_Elmt : Elmt_Id;
4735 Parent_Base : Entity_Id;
4736 Parent_Type : Entity_Id;
4739 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4741 if Is_Non_Empty_List (Interface_List (N)) then
4747 Intf := First (Interface_List (N));
4748 while Present (Intf) loop
4749 T := Find_Type_Of_Subtype_Indic (Intf);
4751 Diagnose_Interface (Intf, T);
4757 Generate_Definition (T);
4759 -- For other than Ada 2012, just enter the name in the current scope
4761 if Ada_Version < Ada_2012 then
4764 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4765 -- case of private type that completes an incomplete type.
4772 Prev := Find_Type_Name (N);
4774 pragma Assert (Prev = T
4775 or else (Ekind (Prev) = E_Incomplete_Type
4776 and then Present (Full_View (Prev))
4777 and then Full_View (Prev) = T));
4781 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4782 Parent_Base := Base_Type (Parent_Type);
4784 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4785 Set_Ekind (T, Ekind (Parent_Type));
4786 Set_Etype (T, Any_Type);
4789 elsif not Is_Tagged_Type (Parent_Type) then
4791 ("parent of type extension must be a tagged type ", Indic);
4794 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4795 Error_Msg_N ("premature derivation of incomplete type", Indic);
4798 elsif Is_Concurrent_Type (Parent_Type) then
4800 ("parent type of a private extension cannot be a synchronized "
4801 & "tagged type (RM 3.9.1 (3/1))", N);
4803 Set_Etype (T, Any_Type);
4804 Set_Ekind (T, E_Limited_Private_Type);
4805 Set_Private_Dependents (T, New_Elmt_List);
4806 Set_Error_Posted (T);
4810 -- Perhaps the parent type should be changed to the class-wide type's
4811 -- specific type in this case to prevent cascading errors ???
4813 if Is_Class_Wide_Type (Parent_Type) then
4815 ("parent of type extension must not be a class-wide type", Indic);
4819 if (not Is_Package_Or_Generic_Package (Current_Scope)
4820 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4821 or else In_Private_Part (Current_Scope)
4823 Error_Msg_N ("invalid context for private extension", N);
4826 -- Set common attributes
4828 Set_Is_Pure (T, Is_Pure (Current_Scope));
4829 Set_Scope (T, Current_Scope);
4830 Set_Ekind (T, E_Record_Type_With_Private);
4831 Init_Size_Align (T);
4832 Set_Default_SSO (T);
4834 Set_Etype (T, Parent_Base);
4835 Propagate_Concurrent_Flags (T, Parent_Base);
4837 Set_Convention (T, Convention (Parent_Type));
4838 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4839 Set_Is_First_Subtype (T);
4840 Make_Class_Wide_Type (T);
4842 if Unknown_Discriminants_Present (N) then
4843 Set_Discriminant_Constraint (T, No_Elist);
4846 Build_Derived_Record_Type (N, Parent_Type, T);
4848 -- A private extension inherits the Default_Initial_Condition pragma
4849 -- coming from any parent type within the derivation chain.
4851 if Has_DIC (Parent_Type) then
4852 Set_Has_Inherited_DIC (T);
4855 -- A private extension inherits any class-wide invariants coming from a
4856 -- parent type or an interface. Note that the invariant procedure of the
4857 -- parent type should not be inherited because the private extension may
4858 -- define invariants of its own.
4860 if Has_Inherited_Invariants (Parent_Type)
4861 or else Has_Inheritable_Invariants (Parent_Type)
4863 Set_Has_Inherited_Invariants (T);
4865 elsif Present (Interfaces (T)) then
4866 Iface_Elmt := First_Elmt (Interfaces (T));
4867 while Present (Iface_Elmt) loop
4868 Iface := Node (Iface_Elmt);
4870 if Has_Inheritable_Invariants (Iface) then
4871 Set_Has_Inherited_Invariants (T);
4875 Next_Elmt (Iface_Elmt);
4879 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4880 -- synchronized formal derived type.
4882 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4883 Set_Is_Limited_Record (T);
4885 -- Formal derived type case
4887 if Is_Generic_Type (T) then
4889 -- The parent must be a tagged limited type or a synchronized
4892 if (not Is_Tagged_Type (Parent_Type)
4893 or else not Is_Limited_Type (Parent_Type))
4895 (not Is_Interface (Parent_Type)
4896 or else not Is_Synchronized_Interface (Parent_Type))
4899 ("parent type of & must be tagged limited or synchronized",
4903 -- The progenitors (if any) must be limited or synchronized
4906 if Present (Interfaces (T)) then
4907 Iface_Elmt := First_Elmt (Interfaces (T));
4908 while Present (Iface_Elmt) loop
4909 Iface := Node (Iface_Elmt);
4911 if not Is_Limited_Interface (Iface)
4912 and then not Is_Synchronized_Interface (Iface)
4915 ("progenitor & must be limited or synchronized",
4919 Next_Elmt (Iface_Elmt);
4923 -- Regular derived extension, the parent must be a limited or
4924 -- synchronized interface.
4927 if not Is_Interface (Parent_Type)
4928 or else (not Is_Limited_Interface (Parent_Type)
4929 and then not Is_Synchronized_Interface (Parent_Type))
4932 ("parent type of & must be limited interface", N, T);
4936 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4937 -- extension with a synchronized parent must be explicitly declared
4938 -- synchronized, because the full view will be a synchronized type.
4939 -- This must be checked before the check for limited types below,
4940 -- to ensure that types declared limited are not allowed to extend
4941 -- synchronized interfaces.
4943 elsif Is_Interface (Parent_Type)
4944 and then Is_Synchronized_Interface (Parent_Type)
4945 and then not Synchronized_Present (N)
4948 ("private extension of& must be explicitly synchronized",
4951 elsif Limited_Present (N) then
4952 Set_Is_Limited_Record (T);
4954 if not Is_Limited_Type (Parent_Type)
4956 (not Is_Interface (Parent_Type)
4957 or else not Is_Limited_Interface (Parent_Type))
4959 Error_Msg_NE ("parent type& of limited extension must be limited",
4964 -- Remember that its parent type has a private extension. Used to warn
4965 -- on public primitives of the parent type defined after its private
4966 -- extensions (see Check_Dispatching_Operation).
4968 Set_Has_Private_Extension (Parent_Type);
4971 if Has_Aspects (N) then
4972 Analyze_Aspect_Specifications (N, T);
4974 end Analyze_Private_Extension_Declaration;
4976 ---------------------------------
4977 -- Analyze_Subtype_Declaration --
4978 ---------------------------------
4980 procedure Analyze_Subtype_Declaration
4982 Skip : Boolean := False)
4984 Id : constant Entity_Id := Defining_Identifier (N);
4985 R_Checks : Check_Result;
4989 Generate_Definition (Id);
4990 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4991 Init_Size_Align (Id);
4993 -- The following guard condition on Enter_Name is to handle cases where
4994 -- the defining identifier has already been entered into the scope but
4995 -- the declaration as a whole needs to be analyzed.
4997 -- This case in particular happens for derived enumeration types. The
4998 -- derived enumeration type is processed as an inserted enumeration type
4999 -- declaration followed by a rewritten subtype declaration. The defining
5000 -- identifier, however, is entered into the name scope very early in the
5001 -- processing of the original type declaration and therefore needs to be
5002 -- avoided here, when the created subtype declaration is analyzed. (See
5003 -- Build_Derived_Types)
5005 -- This also happens when the full view of a private type is derived
5006 -- type with constraints. In this case the entity has been introduced
5007 -- in the private declaration.
5009 -- Finally this happens in some complex cases when validity checks are
5010 -- enabled, where the same subtype declaration may be analyzed twice.
5011 -- This can happen if the subtype is created by the pre-analysis of
5012 -- an attribute tht gives the range of a loop statement, and the loop
5013 -- itself appears within an if_statement that will be rewritten during
5017 or else (Present (Etype (Id))
5018 and then (Is_Private_Type (Etype (Id))
5019 or else Is_Task_Type (Etype (Id))
5020 or else Is_Rewrite_Substitution (N)))
5024 elsif Current_Entity (Id) = Id then
5031 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
5033 -- Class-wide equivalent types of records with unknown discriminants
5034 -- involve the generation of an itype which serves as the private view
5035 -- of a constrained record subtype. In such cases the base type of the
5036 -- current subtype we are processing is the private itype. Use the full
5037 -- of the private itype when decorating various attributes.
5040 and then Is_Private_Type (T)
5041 and then Present (Full_View (T))
5046 -- Inherit common attributes
5048 Set_Is_Volatile (Id, Is_Volatile (T));
5049 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
5050 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
5051 Set_Convention (Id, Convention (T));
5053 -- If ancestor has predicates then so does the subtype, and in addition
5054 -- we must delay the freeze to properly arrange predicate inheritance.
5056 -- The Ancestor_Type test is really unpleasant, there seem to be cases
5057 -- in which T = ID, so the above tests and assignments do nothing???
5059 if Has_Predicates (T)
5060 or else (Present (Ancestor_Subtype (T))
5061 and then Has_Predicates (Ancestor_Subtype (T)))
5063 Set_Has_Predicates (Id);
5064 Set_Has_Delayed_Freeze (Id);
5066 -- Generated subtypes inherit the predicate function from the parent
5067 -- (no aspects to examine on the generated declaration).
5069 if not Comes_From_Source (N) then
5070 Set_Ekind (Id, Ekind (T));
5072 if Present (Predicate_Function (T)) then
5073 Set_Predicate_Function (Id, Predicate_Function (T));
5075 elsif Present (Ancestor_Subtype (T))
5076 and then Has_Predicates (Ancestor_Subtype (T))
5077 and then Present (Predicate_Function (Ancestor_Subtype (T)))
5079 Set_Predicate_Function (Id,
5080 Predicate_Function (Ancestor_Subtype (T)));
5085 -- Subtype of Boolean cannot have a constraint in SPARK
5087 if Is_Boolean_Type (T)
5088 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
5090 Check_SPARK_05_Restriction
5091 ("subtype of Boolean cannot have constraint", N);
5094 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5096 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5102 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
5103 One_Cstr := First (Constraints (Cstr));
5104 while Present (One_Cstr) loop
5106 -- Index or discriminant constraint in SPARK must be a
5110 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
5112 Check_SPARK_05_Restriction
5113 ("subtype mark required", One_Cstr);
5115 -- String subtype must have a lower bound of 1 in SPARK.
5116 -- Note that we do not need to test for the non-static case
5117 -- here, since that was already taken care of in
5118 -- Process_Range_Expr_In_Decl.
5120 elsif Base_Type (T) = Standard_String then
5121 Get_Index_Bounds (One_Cstr, Low, High);
5123 if Is_OK_Static_Expression (Low)
5124 and then Expr_Value (Low) /= 1
5126 Check_SPARK_05_Restriction
5127 ("String subtype must have lower bound of 1", N);
5137 -- In the case where there is no constraint given in the subtype
5138 -- indication, Process_Subtype just returns the Subtype_Mark, so its
5139 -- semantic attributes must be established here.
5141 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
5142 Set_Etype (Id, Base_Type (T));
5144 -- Subtype of unconstrained array without constraint is not allowed
5147 if Is_Array_Type (T) and then not Is_Constrained (T) then
5148 Check_SPARK_05_Restriction
5149 ("subtype of unconstrained array must have constraint", N);
5154 Set_Ekind (Id, E_Array_Subtype);
5155 Copy_Array_Subtype_Attributes (Id, T);
5157 when Decimal_Fixed_Point_Kind =>
5158 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
5159 Set_Digits_Value (Id, Digits_Value (T));
5160 Set_Delta_Value (Id, Delta_Value (T));
5161 Set_Scale_Value (Id, Scale_Value (T));
5162 Set_Small_Value (Id, Small_Value (T));
5163 Set_Scalar_Range (Id, Scalar_Range (T));
5164 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
5165 Set_Is_Constrained (Id, Is_Constrained (T));
5166 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5167 Set_RM_Size (Id, RM_Size (T));
5169 when Enumeration_Kind =>
5170 Set_Ekind (Id, E_Enumeration_Subtype);
5171 Set_First_Literal (Id, First_Literal (Base_Type (T)));
5172 Set_Scalar_Range (Id, Scalar_Range (T));
5173 Set_Is_Character_Type (Id, Is_Character_Type (T));
5174 Set_Is_Constrained (Id, Is_Constrained (T));
5175 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5176 Set_RM_Size (Id, RM_Size (T));
5177 Inherit_Predicate_Flags (Id, T);
5179 when Ordinary_Fixed_Point_Kind =>
5180 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
5181 Set_Scalar_Range (Id, Scalar_Range (T));
5182 Set_Small_Value (Id, Small_Value (T));
5183 Set_Delta_Value (Id, Delta_Value (T));
5184 Set_Is_Constrained (Id, Is_Constrained (T));
5185 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5186 Set_RM_Size (Id, RM_Size (T));
5189 Set_Ekind (Id, E_Floating_Point_Subtype);
5190 Set_Scalar_Range (Id, Scalar_Range (T));
5191 Set_Digits_Value (Id, Digits_Value (T));
5192 Set_Is_Constrained (Id, Is_Constrained (T));
5194 -- If the floating point type has dimensions, these will be
5195 -- inherited subsequently when Analyze_Dimensions is called.
5197 when Signed_Integer_Kind =>
5198 Set_Ekind (Id, E_Signed_Integer_Subtype);
5199 Set_Scalar_Range (Id, Scalar_Range (T));
5200 Set_Is_Constrained (Id, Is_Constrained (T));
5201 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5202 Set_RM_Size (Id, RM_Size (T));
5203 Inherit_Predicate_Flags (Id, T);
5205 when Modular_Integer_Kind =>
5206 Set_Ekind (Id, E_Modular_Integer_Subtype);
5207 Set_Scalar_Range (Id, Scalar_Range (T));
5208 Set_Is_Constrained (Id, Is_Constrained (T));
5209 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5210 Set_RM_Size (Id, RM_Size (T));
5211 Inherit_Predicate_Flags (Id, T);
5213 when Class_Wide_Kind =>
5214 Set_Ekind (Id, E_Class_Wide_Subtype);
5215 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5216 Set_Cloned_Subtype (Id, T);
5217 Set_Is_Tagged_Type (Id, True);
5218 Set_Has_Unknown_Discriminants
5220 Set_No_Tagged_Streams_Pragma
5221 (Id, No_Tagged_Streams_Pragma (T));
5223 if Ekind (T) = E_Class_Wide_Subtype then
5224 Set_Equivalent_Type (Id, Equivalent_Type (T));
5227 when E_Record_Subtype
5230 Set_Ekind (Id, E_Record_Subtype);
5232 if Ekind (T) = E_Record_Subtype
5233 and then Present (Cloned_Subtype (T))
5235 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5237 Set_Cloned_Subtype (Id, T);
5240 Set_First_Entity (Id, First_Entity (T));
5241 Set_Last_Entity (Id, Last_Entity (T));
5242 Set_Has_Discriminants (Id, Has_Discriminants (T));
5243 Set_Is_Constrained (Id, Is_Constrained (T));
5244 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5245 Set_Has_Implicit_Dereference
5246 (Id, Has_Implicit_Dereference (T));
5247 Set_Has_Unknown_Discriminants
5248 (Id, Has_Unknown_Discriminants (T));
5250 if Has_Discriminants (T) then
5251 Set_Discriminant_Constraint
5252 (Id, Discriminant_Constraint (T));
5253 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5255 elsif Has_Unknown_Discriminants (Id) then
5256 Set_Discriminant_Constraint (Id, No_Elist);
5259 if Is_Tagged_Type (T) then
5260 Set_Is_Tagged_Type (Id, True);
5261 Set_No_Tagged_Streams_Pragma
5262 (Id, No_Tagged_Streams_Pragma (T));
5263 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5264 Set_Direct_Primitive_Operations
5265 (Id, Direct_Primitive_Operations (T));
5266 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5268 if Is_Interface (T) then
5269 Set_Is_Interface (Id);
5270 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5274 when Private_Kind =>
5275 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5276 Set_Has_Discriminants (Id, Has_Discriminants (T));
5277 Set_Is_Constrained (Id, Is_Constrained (T));
5278 Set_First_Entity (Id, First_Entity (T));
5279 Set_Last_Entity (Id, Last_Entity (T));
5280 Set_Private_Dependents (Id, New_Elmt_List);
5281 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5282 Set_Has_Implicit_Dereference
5283 (Id, Has_Implicit_Dereference (T));
5284 Set_Has_Unknown_Discriminants
5285 (Id, Has_Unknown_Discriminants (T));
5286 Set_Known_To_Have_Preelab_Init
5287 (Id, Known_To_Have_Preelab_Init (T));
5289 if Is_Tagged_Type (T) then
5290 Set_Is_Tagged_Type (Id);
5291 Set_No_Tagged_Streams_Pragma (Id,
5292 No_Tagged_Streams_Pragma (T));
5293 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5294 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5295 Set_Direct_Primitive_Operations (Id,
5296 Direct_Primitive_Operations (T));
5299 -- In general the attributes of the subtype of a private type
5300 -- are the attributes of the partial view of parent. However,
5301 -- the full view may be a discriminated type, and the subtype
5302 -- must share the discriminant constraint to generate correct
5303 -- calls to initialization procedures.
5305 if Has_Discriminants (T) then
5306 Set_Discriminant_Constraint
5307 (Id, Discriminant_Constraint (T));
5308 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5310 elsif Present (Full_View (T))
5311 and then Has_Discriminants (Full_View (T))
5313 Set_Discriminant_Constraint
5314 (Id, Discriminant_Constraint (Full_View (T)));
5315 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5317 -- This would seem semantically correct, but apparently
5318 -- generates spurious errors about missing components ???
5320 -- Set_Has_Discriminants (Id);
5323 Prepare_Private_Subtype_Completion (Id, N);
5325 -- If this is the subtype of a constrained private type with
5326 -- discriminants that has got a full view and we also have
5327 -- built a completion just above, show that the completion
5328 -- is a clone of the full view to the back-end.
5330 if Has_Discriminants (T)
5331 and then not Has_Unknown_Discriminants (T)
5332 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5333 and then Present (Full_View (T))
5334 and then Present (Full_View (Id))
5336 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5340 Set_Ekind (Id, E_Access_Subtype);
5341 Set_Is_Constrained (Id, Is_Constrained (T));
5342 Set_Is_Access_Constant
5343 (Id, Is_Access_Constant (T));
5344 Set_Directly_Designated_Type
5345 (Id, Designated_Type (T));
5346 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5348 -- A Pure library_item must not contain the declaration of a
5349 -- named access type, except within a subprogram, generic
5350 -- subprogram, task unit, or protected unit, or if it has
5351 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5353 if Comes_From_Source (Id)
5354 and then In_Pure_Unit
5355 and then not In_Subprogram_Task_Protected_Unit
5356 and then not No_Pool_Assigned (Id)
5359 ("named access types not allowed in pure unit", N);
5362 when Concurrent_Kind =>
5363 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5364 Set_Corresponding_Record_Type (Id,
5365 Corresponding_Record_Type (T));
5366 Set_First_Entity (Id, First_Entity (T));
5367 Set_First_Private_Entity (Id, First_Private_Entity (T));
5368 Set_Has_Discriminants (Id, Has_Discriminants (T));
5369 Set_Is_Constrained (Id, Is_Constrained (T));
5370 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5371 Set_Last_Entity (Id, Last_Entity (T));
5373 if Is_Tagged_Type (T) then
5374 Set_No_Tagged_Streams_Pragma
5375 (Id, No_Tagged_Streams_Pragma (T));
5378 if Has_Discriminants (T) then
5379 Set_Discriminant_Constraint
5380 (Id, Discriminant_Constraint (T));
5381 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5384 when Incomplete_Kind =>
5385 if Ada_Version >= Ada_2005 then
5387 -- In Ada 2005 an incomplete type can be explicitly tagged:
5388 -- propagate indication. Note that we also have to include
5389 -- subtypes for Ada 2012 extended use of incomplete types.
5391 Set_Ekind (Id, E_Incomplete_Subtype);
5392 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5393 Set_Private_Dependents (Id, New_Elmt_List);
5395 if Is_Tagged_Type (Id) then
5396 Set_No_Tagged_Streams_Pragma
5397 (Id, No_Tagged_Streams_Pragma (T));
5398 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5401 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5402 -- incomplete type visible through a limited with clause.
5404 if From_Limited_With (T)
5405 and then Present (Non_Limited_View (T))
5407 Set_From_Limited_With (Id);
5408 Set_Non_Limited_View (Id, Non_Limited_View (T));
5410 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5411 -- to the private dependents of the original incomplete
5412 -- type for future transformation.
5415 Append_Elmt (Id, Private_Dependents (T));
5418 -- If the subtype name denotes an incomplete type an error
5419 -- was already reported by Process_Subtype.
5422 Set_Etype (Id, Any_Type);
5426 raise Program_Error;
5430 if Etype (Id) = Any_Type then
5434 -- Some common processing on all types
5436 Set_Size_Info (Id, T);
5437 Set_First_Rep_Item (Id, First_Rep_Item (T));
5439 -- If the parent type is a generic actual, so is the subtype. This may
5440 -- happen in a nested instance. Why Comes_From_Source test???
5442 if not Comes_From_Source (N) then
5443 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5446 -- If this is a subtype declaration for an actual in an instance,
5447 -- inherit static and dynamic predicates if any.
5449 -- If declaration has no aspect specifications, inherit predicate
5450 -- info as well. Unclear how to handle the case of both specified
5451 -- and inherited predicates ??? Other inherited aspects, such as
5452 -- invariants, should be OK, but the combination with later pragmas
5453 -- may also require special merging.
5455 if Has_Predicates (T)
5456 and then Present (Predicate_Function (T))
5458 ((In_Instance and then not Comes_From_Source (N))
5459 or else No (Aspect_Specifications (N)))
5461 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5463 if Has_Static_Predicate (T) then
5464 Set_Has_Static_Predicate (Id);
5465 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5469 -- Remaining processing depends on characteristics of base type
5473 Set_Is_Immediately_Visible (Id, True);
5474 Set_Depends_On_Private (Id, Has_Private_Component (T));
5475 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5477 if Is_Interface (T) then
5478 Set_Is_Interface (Id);
5481 if Present (Generic_Parent_Type (N))
5483 (Nkind (Parent (Generic_Parent_Type (N))) /=
5484 N_Formal_Type_Declaration
5485 or else Nkind (Formal_Type_Definition
5486 (Parent (Generic_Parent_Type (N)))) /=
5487 N_Formal_Private_Type_Definition)
5489 if Is_Tagged_Type (Id) then
5491 -- If this is a generic actual subtype for a synchronized type,
5492 -- the primitive operations are those of the corresponding record
5493 -- for which there is a separate subtype declaration.
5495 if Is_Concurrent_Type (Id) then
5497 elsif Is_Class_Wide_Type (Id) then
5498 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5500 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5503 elsif Scope (Etype (Id)) /= Standard_Standard then
5504 Derive_Subprograms (Generic_Parent_Type (N), Id);
5508 if Is_Private_Type (T) and then Present (Full_View (T)) then
5509 Conditional_Delay (Id, Full_View (T));
5511 -- The subtypes of components or subcomponents of protected types
5512 -- do not need freeze nodes, which would otherwise appear in the
5513 -- wrong scope (before the freeze node for the protected type). The
5514 -- proper subtypes are those of the subcomponents of the corresponding
5517 elsif Ekind (Scope (Id)) /= E_Protected_Type
5518 and then Present (Scope (Scope (Id))) -- error defense
5519 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5521 Conditional_Delay (Id, T);
5524 -- Check that Constraint_Error is raised for a scalar subtype indication
5525 -- when the lower or upper bound of a non-null range lies outside the
5526 -- range of the type mark.
5528 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5529 if Is_Scalar_Type (Etype (Id))
5530 and then Scalar_Range (Id) /=
5532 (Etype (Subtype_Mark (Subtype_Indication (N))))
5536 Etype (Subtype_Mark (Subtype_Indication (N))));
5538 -- In the array case, check compatibility for each index
5540 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5542 -- This really should be a subprogram that finds the indications
5546 Subt_Index : Node_Id := First_Index (Id);
5547 Target_Index : Node_Id :=
5549 (Subtype_Mark (Subtype_Indication (N))));
5550 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5553 while Present (Subt_Index) loop
5554 if ((Nkind (Subt_Index) = N_Identifier
5555 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5556 or else Nkind (Subt_Index) = N_Subtype_Indication)
5558 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5561 Target_Typ : constant Entity_Id :=
5562 Etype (Target_Index);
5566 (Scalar_Range (Etype (Subt_Index)),
5569 Defining_Identifier (N));
5571 -- Reset Has_Dynamic_Range_Check on the subtype to
5572 -- prevent elision of the index check due to a dynamic
5573 -- check generated for a preceding index (needed since
5574 -- Insert_Range_Checks tries to avoid generating
5575 -- redundant checks on a given declaration).
5577 Set_Has_Dynamic_Range_Check (N, False);
5583 Sloc (Defining_Identifier (N)));
5585 -- Record whether this index involved a dynamic check
5588 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5592 Next_Index (Subt_Index);
5593 Next_Index (Target_Index);
5596 -- Finally, mark whether the subtype involves dynamic checks
5598 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5603 Set_Optimize_Alignment_Flags (Id);
5604 Check_Eliminated (Id);
5607 if Has_Aspects (N) then
5608 Analyze_Aspect_Specifications (N, Id);
5611 Analyze_Dimension (N);
5613 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5614 -- indications on composite types where the constraints are dynamic.
5615 -- Note that object declarations and aggregates generate implicit
5616 -- subtype declarations, which this covers. One special case is that the
5617 -- implicitly generated "=" for discriminated types includes an
5618 -- offending subtype declaration, which is harmless, so we ignore it
5621 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5623 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5625 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5626 and then not (Is_Internal (Id)
5627 and then Is_TSS (Scope (Id),
5628 TSS_Composite_Equality))
5629 and then not Within_Init_Proc
5630 and then not All_Composite_Constraints_Static (Cstr)
5632 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5636 end Analyze_Subtype_Declaration;
5638 --------------------------------
5639 -- Analyze_Subtype_Indication --
5640 --------------------------------
5642 procedure Analyze_Subtype_Indication (N : Node_Id) is
5643 T : constant Entity_Id := Subtype_Mark (N);
5644 R : constant Node_Id := Range_Expression (Constraint (N));
5651 Set_Etype (N, Etype (R));
5652 Resolve (R, Entity (T));
5654 Set_Error_Posted (R);
5655 Set_Error_Posted (T);
5657 end Analyze_Subtype_Indication;
5659 --------------------------
5660 -- Analyze_Variant_Part --
5661 --------------------------
5663 procedure Analyze_Variant_Part (N : Node_Id) is
5664 Discr_Name : Node_Id;
5665 Discr_Type : Entity_Id;
5667 procedure Process_Variant (A : Node_Id);
5668 -- Analyze declarations for a single variant
5670 package Analyze_Variant_Choices is
5671 new Generic_Analyze_Choices (Process_Variant);
5672 use Analyze_Variant_Choices;
5674 ---------------------
5675 -- Process_Variant --
5676 ---------------------
5678 procedure Process_Variant (A : Node_Id) is
5679 CL : constant Node_Id := Component_List (A);
5681 if not Null_Present (CL) then
5682 Analyze_Declarations (Component_Items (CL));
5684 if Present (Variant_Part (CL)) then
5685 Analyze (Variant_Part (CL));
5688 end Process_Variant;
5690 -- Start of processing for Analyze_Variant_Part
5693 Discr_Name := Name (N);
5694 Analyze (Discr_Name);
5696 -- If Discr_Name bad, get out (prevent cascaded errors)
5698 if Etype (Discr_Name) = Any_Type then
5702 -- Check invalid discriminant in variant part
5704 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5705 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5708 Discr_Type := Etype (Entity (Discr_Name));
5710 if not Is_Discrete_Type (Discr_Type) then
5712 ("discriminant in a variant part must be of a discrete type",
5717 -- Now analyze the choices, which also analyzes the declarations that
5718 -- are associated with each choice.
5720 Analyze_Choices (Variants (N), Discr_Type);
5722 -- Note: we used to instantiate and call Check_Choices here to check
5723 -- that the choices covered the discriminant, but it's too early to do
5724 -- that because of statically predicated subtypes, whose analysis may
5725 -- be deferred to their freeze point which may be as late as the freeze
5726 -- point of the containing record. So this call is now to be found in
5727 -- Freeze_Record_Declaration.
5729 end Analyze_Variant_Part;
5731 ----------------------------
5732 -- Array_Type_Declaration --
5733 ----------------------------
5735 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5736 Component_Def : constant Node_Id := Component_Definition (Def);
5737 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5738 P : constant Node_Id := Parent (Def);
5739 Element_Type : Entity_Id;
5740 Implicit_Base : Entity_Id;
5744 Related_Id : Entity_Id := Empty;
5747 if Nkind (Def) = N_Constrained_Array_Definition then
5748 Index := First (Discrete_Subtype_Definitions (Def));
5750 Index := First (Subtype_Marks (Def));
5753 -- Find proper names for the implicit types which may be public. In case
5754 -- of anonymous arrays we use the name of the first object of that type
5758 Related_Id := Defining_Identifier (P);
5764 while Present (Index) loop
5767 -- Test for odd case of trying to index a type by the type itself
5769 if Is_Entity_Name (Index) and then Entity (Index) = T then
5770 Error_Msg_N ("type& cannot be indexed by itself", Index);
5771 Set_Entity (Index, Standard_Boolean);
5772 Set_Etype (Index, Standard_Boolean);
5775 -- Check SPARK restriction requiring a subtype mark
5777 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5778 Check_SPARK_05_Restriction ("subtype mark required", Index);
5781 -- Add a subtype declaration for each index of private array type
5782 -- declaration whose etype is also private. For example:
5785 -- type Index is private;
5787 -- type Table is array (Index) of ...
5790 -- This is currently required by the expander for the internally
5791 -- generated equality subprogram of records with variant parts in
5792 -- which the etype of some component is such private type.
5794 if Ekind (Current_Scope) = E_Package
5795 and then In_Private_Part (Current_Scope)
5796 and then Has_Private_Declaration (Etype (Index))
5799 Loc : constant Source_Ptr := Sloc (Def);
5804 New_E := Make_Temporary (Loc, 'T');
5805 Set_Is_Internal (New_E);
5808 Make_Subtype_Declaration (Loc,
5809 Defining_Identifier => New_E,
5810 Subtype_Indication =>
5811 New_Occurrence_Of (Etype (Index), Loc));
5813 Insert_Before (Parent (Def), Decl);
5815 Set_Etype (Index, New_E);
5817 -- If the index is a range the Entity attribute is not
5818 -- available. Example:
5821 -- type T is private;
5823 -- type T is new Natural;
5824 -- Table : array (T(1) .. T(10)) of Boolean;
5827 if Nkind (Index) /= N_Range then
5828 Set_Entity (Index, New_E);
5833 Make_Index (Index, P, Related_Id, Nb_Index);
5835 -- Check error of subtype with predicate for index type
5837 Bad_Predicated_Subtype_Use
5838 ("subtype& has predicate, not allowed as index subtype",
5839 Index, Etype (Index));
5841 -- Move to next index
5844 Nb_Index := Nb_Index + 1;
5847 -- Process subtype indication if one is present
5849 if Present (Component_Typ) then
5850 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5852 Set_Etype (Component_Typ, Element_Type);
5854 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5855 Check_SPARK_05_Restriction
5856 ("subtype mark required", Component_Typ);
5859 -- Ada 2005 (AI-230): Access Definition case
5861 else pragma Assert (Present (Access_Definition (Component_Def)));
5863 -- Indicate that the anonymous access type is created by the
5864 -- array type declaration.
5866 Element_Type := Access_Definition
5868 N => Access_Definition (Component_Def));
5869 Set_Is_Local_Anonymous_Access (Element_Type);
5871 -- Propagate the parent. This field is needed if we have to generate
5872 -- the master_id associated with an anonymous access to task type
5873 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5875 Set_Parent (Element_Type, Parent (T));
5877 -- Ada 2005 (AI-230): In case of components that are anonymous access
5878 -- types the level of accessibility depends on the enclosing type
5881 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5883 -- Ada 2005 (AI-254)
5886 CD : constant Node_Id :=
5887 Access_To_Subprogram_Definition
5888 (Access_Definition (Component_Def));
5890 if Present (CD) and then Protected_Present (CD) then
5892 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5897 -- Constrained array case
5900 T := Create_Itype (E_Void, P, Related_Id, 'T');
5903 if Nkind (Def) = N_Constrained_Array_Definition then
5905 -- Establish Implicit_Base as unconstrained base type
5907 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5909 Set_Etype (Implicit_Base, Implicit_Base);
5910 Set_Scope (Implicit_Base, Current_Scope);
5911 Set_Has_Delayed_Freeze (Implicit_Base);
5912 Set_Default_SSO (Implicit_Base);
5914 -- The constrained array type is a subtype of the unconstrained one
5916 Set_Ekind (T, E_Array_Subtype);
5917 Init_Size_Align (T);
5918 Set_Etype (T, Implicit_Base);
5919 Set_Scope (T, Current_Scope);
5920 Set_Is_Constrained (T);
5922 First (Discrete_Subtype_Definitions (Def)));
5923 Set_Has_Delayed_Freeze (T);
5925 -- Complete setup of implicit base type
5927 Set_Component_Size (Implicit_Base, Uint_0);
5928 Set_Component_Type (Implicit_Base, Element_Type);
5929 Set_Finalize_Storage_Only
5931 Finalize_Storage_Only (Element_Type));
5932 Set_First_Index (Implicit_Base, First_Index (T));
5933 Set_Has_Controlled_Component
5935 Has_Controlled_Component (Element_Type)
5936 or else Is_Controlled_Active (Element_Type));
5937 Set_Packed_Array_Impl_Type
5938 (Implicit_Base, Empty);
5940 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
5942 -- Unconstrained array case
5945 Set_Ekind (T, E_Array_Type);
5946 Init_Size_Align (T);
5948 Set_Scope (T, Current_Scope);
5949 Set_Component_Size (T, Uint_0);
5950 Set_Is_Constrained (T, False);
5951 Set_First_Index (T, First (Subtype_Marks (Def)));
5952 Set_Has_Delayed_Freeze (T, True);
5953 Propagate_Concurrent_Flags (T, Element_Type);
5954 Set_Has_Controlled_Component (T, Has_Controlled_Component
5957 Is_Controlled_Active (Element_Type));
5958 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5960 Set_Default_SSO (T);
5963 -- Common attributes for both cases
5965 Set_Component_Type (Base_Type (T), Element_Type);
5966 Set_Packed_Array_Impl_Type (T, Empty);
5968 if Aliased_Present (Component_Definition (Def)) then
5969 Check_SPARK_05_Restriction
5970 ("aliased is not allowed", Component_Definition (Def));
5971 Set_Has_Aliased_Components (Etype (T));
5974 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5975 -- array type to ensure that objects of this type are initialized.
5977 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5978 Set_Can_Never_Be_Null (T);
5980 if Null_Exclusion_Present (Component_Definition (Def))
5982 -- No need to check itypes because in their case this check was
5983 -- done at their point of creation
5985 and then not Is_Itype (Element_Type)
5988 ("`NOT NULL` not allowed (null already excluded)",
5989 Subtype_Indication (Component_Definition (Def)));
5993 Priv := Private_Component (Element_Type);
5995 if Present (Priv) then
5997 -- Check for circular definitions
5999 if Priv = Any_Type then
6000 Set_Component_Type (Etype (T), Any_Type);
6002 -- There is a gap in the visibility of operations on the composite
6003 -- type only if the component type is defined in a different scope.
6005 elsif Scope (Priv) = Current_Scope then
6008 elsif Is_Limited_Type (Priv) then
6009 Set_Is_Limited_Composite (Etype (T));
6010 Set_Is_Limited_Composite (T);
6012 Set_Is_Private_Composite (Etype (T));
6013 Set_Is_Private_Composite (T);
6017 -- A syntax error in the declaration itself may lead to an empty index
6018 -- list, in which case do a minimal patch.
6020 if No (First_Index (T)) then
6021 Error_Msg_N ("missing index definition in array type declaration", T);
6024 Indexes : constant List_Id :=
6025 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
6027 Set_Discrete_Subtype_Definitions (Def, Indexes);
6028 Set_First_Index (T, First (Indexes));
6033 -- Create a concatenation operator for the new type. Internal array
6034 -- types created for packed entities do not need such, they are
6035 -- compatible with the user-defined type.
6037 if Number_Dimensions (T) = 1
6038 and then not Is_Packed_Array_Impl_Type (T)
6040 New_Concatenation_Op (T);
6043 -- In the case of an unconstrained array the parser has already verified
6044 -- that all the indexes are unconstrained but we still need to make sure
6045 -- that the element type is constrained.
6047 if not Is_Definite_Subtype (Element_Type) then
6049 ("unconstrained element type in array declaration",
6050 Subtype_Indication (Component_Def));
6052 elsif Is_Abstract_Type (Element_Type) then
6054 ("the type of a component cannot be abstract",
6055 Subtype_Indication (Component_Def));
6058 -- There may be an invariant declared for the component type, but
6059 -- the construction of the component invariant checking procedure
6060 -- takes place during expansion.
6061 end Array_Type_Declaration;
6063 ------------------------------------------------------
6064 -- Replace_Anonymous_Access_To_Protected_Subprogram --
6065 ------------------------------------------------------
6067 function Replace_Anonymous_Access_To_Protected_Subprogram
6068 (N : Node_Id) return Entity_Id
6070 Loc : constant Source_Ptr := Sloc (N);
6072 Curr_Scope : constant Scope_Stack_Entry :=
6073 Scope_Stack.Table (Scope_Stack.Last);
6075 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
6078 -- Access definition in declaration
6081 -- Object definition or formal definition with an access definition
6084 -- Declaration of anonymous access to subprogram type
6087 -- Original specification in access to subprogram
6092 Set_Is_Internal (Anon);
6095 when N_Constrained_Array_Definition
6096 | N_Component_Declaration
6097 | N_Unconstrained_Array_Definition
6099 Comp := Component_Definition (N);
6100 Acc := Access_Definition (Comp);
6102 when N_Discriminant_Specification =>
6103 Comp := Discriminant_Type (N);
6106 when N_Parameter_Specification =>
6107 Comp := Parameter_Type (N);
6110 when N_Access_Function_Definition =>
6111 Comp := Result_Definition (N);
6114 when N_Object_Declaration =>
6115 Comp := Object_Definition (N);
6118 when N_Function_Specification =>
6119 Comp := Result_Definition (N);
6123 raise Program_Error;
6126 Spec := Access_To_Subprogram_Definition (Acc);
6129 Make_Full_Type_Declaration (Loc,
6130 Defining_Identifier => Anon,
6131 Type_Definition => Copy_Separate_Tree (Spec));
6133 Mark_Rewrite_Insertion (Decl);
6135 -- In ASIS mode, analyze the profile on the original node, because
6136 -- the separate copy does not provide enough links to recover the
6137 -- original tree. Analysis is limited to type annotations, within
6138 -- a temporary scope that serves as an anonymous subprogram to collect
6139 -- otherwise useless temporaries and itypes.
6143 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
6146 if Nkind (Spec) = N_Access_Function_Definition then
6147 Set_Ekind (Typ, E_Function);
6149 Set_Ekind (Typ, E_Procedure);
6152 Set_Parent (Typ, N);
6153 Set_Scope (Typ, Current_Scope);
6156 -- Nothing to do if procedure is parameterless
6158 if Present (Parameter_Specifications (Spec)) then
6159 Process_Formals (Parameter_Specifications (Spec), Spec);
6162 if Nkind (Spec) = N_Access_Function_Definition then
6164 Def : constant Node_Id := Result_Definition (Spec);
6167 -- The result might itself be an anonymous access type, so
6170 if Nkind (Def) = N_Access_Definition then
6171 if Present (Access_To_Subprogram_Definition (Def)) then
6174 Replace_Anonymous_Access_To_Protected_Subprogram
6177 Find_Type (Subtype_Mark (Def));
6190 -- Insert the new declaration in the nearest enclosing scope. If the
6191 -- parent is a body and N is its return type, the declaration belongs
6192 -- in the enclosing scope. Likewise if N is the type of a parameter.
6196 if Nkind (N) = N_Function_Specification
6197 and then Nkind (P) = N_Subprogram_Body
6200 elsif Nkind (N) = N_Parameter_Specification
6201 and then Nkind (P) in N_Subprogram_Specification
6202 and then Nkind (Parent (P)) = N_Subprogram_Body
6204 P := Parent (Parent (P));
6207 while Present (P) and then not Has_Declarations (P) loop
6211 pragma Assert (Present (P));
6213 if Nkind (P) = N_Package_Specification then
6214 Prepend (Decl, Visible_Declarations (P));
6216 Prepend (Decl, Declarations (P));
6219 -- Replace the anonymous type with an occurrence of the new declaration.
6220 -- In all cases the rewritten node does not have the null-exclusion
6221 -- attribute because (if present) it was already inherited by the
6222 -- anonymous entity (Anon). Thus, in case of components we do not
6223 -- inherit this attribute.
6225 if Nkind (N) = N_Parameter_Specification then
6226 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6227 Set_Etype (Defining_Identifier (N), Anon);
6228 Set_Null_Exclusion_Present (N, False);
6230 elsif Nkind (N) = N_Object_Declaration then
6231 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6232 Set_Etype (Defining_Identifier (N), Anon);
6234 elsif Nkind (N) = N_Access_Function_Definition then
6235 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6237 elsif Nkind (N) = N_Function_Specification then
6238 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6239 Set_Etype (Defining_Unit_Name (N), Anon);
6243 Make_Component_Definition (Loc,
6244 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6247 Mark_Rewrite_Insertion (Comp);
6249 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6250 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6251 and then not Is_Type (Current_Scope))
6254 -- Declaration can be analyzed in the current scope.
6259 -- Temporarily remove the current scope (record or subprogram) from
6260 -- the stack to add the new declarations to the enclosing scope.
6261 -- The anonymous entity is an Itype with the proper attributes.
6263 Scope_Stack.Decrement_Last;
6265 Set_Is_Itype (Anon);
6266 Set_Associated_Node_For_Itype (Anon, N);
6267 Scope_Stack.Append (Curr_Scope);
6270 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6271 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6273 end Replace_Anonymous_Access_To_Protected_Subprogram;
6275 -------------------------------
6276 -- Build_Derived_Access_Type --
6277 -------------------------------
6279 procedure Build_Derived_Access_Type
6281 Parent_Type : Entity_Id;
6282 Derived_Type : Entity_Id)
6284 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6286 Desig_Type : Entity_Id;
6288 Discr_Con_Elist : Elist_Id;
6289 Discr_Con_El : Elmt_Id;
6293 -- Set the designated type so it is available in case this is an access
6294 -- to a self-referential type, e.g. a standard list type with a next
6295 -- pointer. Will be reset after subtype is built.
6297 Set_Directly_Designated_Type
6298 (Derived_Type, Designated_Type (Parent_Type));
6300 Subt := Process_Subtype (S, N);
6302 if Nkind (S) /= N_Subtype_Indication
6303 and then Subt /= Base_Type (Subt)
6305 Set_Ekind (Derived_Type, E_Access_Subtype);
6308 if Ekind (Derived_Type) = E_Access_Subtype then
6310 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6311 Ibase : constant Entity_Id :=
6312 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6313 Svg_Chars : constant Name_Id := Chars (Ibase);
6314 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6317 Copy_Node (Pbase, Ibase);
6319 -- Restore Itype status after Copy_Node
6321 Set_Is_Itype (Ibase);
6322 Set_Associated_Node_For_Itype (Ibase, N);
6324 Set_Chars (Ibase, Svg_Chars);
6325 Set_Next_Entity (Ibase, Svg_Next_E);
6326 Set_Sloc (Ibase, Sloc (Derived_Type));
6327 Set_Scope (Ibase, Scope (Derived_Type));
6328 Set_Freeze_Node (Ibase, Empty);
6329 Set_Is_Frozen (Ibase, False);
6330 Set_Comes_From_Source (Ibase, False);
6331 Set_Is_First_Subtype (Ibase, False);
6333 Set_Etype (Ibase, Pbase);
6334 Set_Etype (Derived_Type, Ibase);
6338 Set_Directly_Designated_Type
6339 (Derived_Type, Designated_Type (Subt));
6341 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6342 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6343 Set_Size_Info (Derived_Type, Parent_Type);
6344 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6345 Set_Depends_On_Private (Derived_Type,
6346 Has_Private_Component (Derived_Type));
6347 Conditional_Delay (Derived_Type, Subt);
6349 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6350 -- that it is not redundant.
6352 if Null_Exclusion_Present (Type_Definition (N)) then
6353 Set_Can_Never_Be_Null (Derived_Type);
6355 elsif Can_Never_Be_Null (Parent_Type) then
6356 Set_Can_Never_Be_Null (Derived_Type);
6359 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6360 -- the root type for this information.
6362 -- Apply range checks to discriminants for derived record case
6363 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6365 Desig_Type := Designated_Type (Derived_Type);
6367 if Is_Composite_Type (Desig_Type)
6368 and then (not Is_Array_Type (Desig_Type))
6369 and then Has_Discriminants (Desig_Type)
6370 and then Base_Type (Desig_Type) /= Desig_Type
6372 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6373 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6375 Discr := First_Discriminant (Base_Type (Desig_Type));
6376 while Present (Discr_Con_El) loop
6377 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6378 Next_Elmt (Discr_Con_El);
6379 Next_Discriminant (Discr);
6382 end Build_Derived_Access_Type;
6384 ------------------------------
6385 -- Build_Derived_Array_Type --
6386 ------------------------------
6388 procedure Build_Derived_Array_Type
6390 Parent_Type : Entity_Id;
6391 Derived_Type : Entity_Id)
6393 Loc : constant Source_Ptr := Sloc (N);
6394 Tdef : constant Node_Id := Type_Definition (N);
6395 Indic : constant Node_Id := Subtype_Indication (Tdef);
6396 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6397 Implicit_Base : Entity_Id;
6398 New_Indic : Node_Id;
6400 procedure Make_Implicit_Base;
6401 -- If the parent subtype is constrained, the derived type is a subtype
6402 -- of an implicit base type derived from the parent base.
6404 ------------------------
6405 -- Make_Implicit_Base --
6406 ------------------------
6408 procedure Make_Implicit_Base is
6411 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6413 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6414 Set_Etype (Implicit_Base, Parent_Base);
6416 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6417 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6419 Set_Has_Delayed_Freeze (Implicit_Base, True);
6420 end Make_Implicit_Base;
6422 -- Start of processing for Build_Derived_Array_Type
6425 if not Is_Constrained (Parent_Type) then
6426 if Nkind (Indic) /= N_Subtype_Indication then
6427 Set_Ekind (Derived_Type, E_Array_Type);
6429 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6430 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6432 Set_Has_Delayed_Freeze (Derived_Type, True);
6436 Set_Etype (Derived_Type, Implicit_Base);
6439 Make_Subtype_Declaration (Loc,
6440 Defining_Identifier => Derived_Type,
6441 Subtype_Indication =>
6442 Make_Subtype_Indication (Loc,
6443 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6444 Constraint => Constraint (Indic)));
6446 Rewrite (N, New_Indic);
6451 if Nkind (Indic) /= N_Subtype_Indication then
6454 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6455 Set_Etype (Derived_Type, Implicit_Base);
6456 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6459 Error_Msg_N ("illegal constraint on constrained type", Indic);
6463 -- If parent type is not a derived type itself, and is declared in
6464 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6465 -- the new type's concatenation operator since Derive_Subprograms
6466 -- will not inherit the parent's operator. If the parent type is
6467 -- unconstrained, the operator is of the unconstrained base type.
6469 if Number_Dimensions (Parent_Type) = 1
6470 and then not Is_Limited_Type (Parent_Type)
6471 and then not Is_Derived_Type (Parent_Type)
6472 and then not Is_Package_Or_Generic_Package
6473 (Scope (Base_Type (Parent_Type)))
6475 if not Is_Constrained (Parent_Type)
6476 and then Is_Constrained (Derived_Type)
6478 New_Concatenation_Op (Implicit_Base);
6480 New_Concatenation_Op (Derived_Type);
6483 end Build_Derived_Array_Type;
6485 -----------------------------------
6486 -- Build_Derived_Concurrent_Type --
6487 -----------------------------------
6489 procedure Build_Derived_Concurrent_Type
6491 Parent_Type : Entity_Id;
6492 Derived_Type : Entity_Id)
6494 Loc : constant Source_Ptr := Sloc (N);
6496 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6497 Corr_Decl : Node_Id;
6498 Corr_Decl_Needed : Boolean;
6499 -- If the derived type has fewer discriminants than its parent, the
6500 -- corresponding record is also a derived type, in order to account for
6501 -- the bound discriminants. We create a full type declaration for it in
6504 Constraint_Present : constant Boolean :=
6505 Nkind (Subtype_Indication (Type_Definition (N))) =
6506 N_Subtype_Indication;
6508 D_Constraint : Node_Id;
6509 New_Constraint : Elist_Id;
6510 Old_Disc : Entity_Id;
6511 New_Disc : Entity_Id;
6515 Set_Stored_Constraint (Derived_Type, No_Elist);
6516 Corr_Decl_Needed := False;
6519 if Present (Discriminant_Specifications (N))
6520 and then Constraint_Present
6522 Old_Disc := First_Discriminant (Parent_Type);
6523 New_Disc := First (Discriminant_Specifications (N));
6524 while Present (New_Disc) and then Present (Old_Disc) loop
6525 Next_Discriminant (Old_Disc);
6530 if Present (Old_Disc) and then Expander_Active then
6532 -- The new type has fewer discriminants, so we need to create a new
6533 -- corresponding record, which is derived from the corresponding
6534 -- record of the parent, and has a stored constraint that captures
6535 -- the values of the discriminant constraints. The corresponding
6536 -- record is needed only if expander is active and code generation is
6539 -- The type declaration for the derived corresponding record has the
6540 -- same discriminant part and constraints as the current declaration.
6541 -- Copy the unanalyzed tree to build declaration.
6543 Corr_Decl_Needed := True;
6544 New_N := Copy_Separate_Tree (N);
6547 Make_Full_Type_Declaration (Loc,
6548 Defining_Identifier => Corr_Record,
6549 Discriminant_Specifications =>
6550 Discriminant_Specifications (New_N),
6552 Make_Derived_Type_Definition (Loc,
6553 Subtype_Indication =>
6554 Make_Subtype_Indication (Loc,
6557 (Corresponding_Record_Type (Parent_Type), Loc),
6560 (Subtype_Indication (Type_Definition (New_N))))));
6563 -- Copy Storage_Size and Relative_Deadline variables if task case
6565 if Is_Task_Type (Parent_Type) then
6566 Set_Storage_Size_Variable (Derived_Type,
6567 Storage_Size_Variable (Parent_Type));
6568 Set_Relative_Deadline_Variable (Derived_Type,
6569 Relative_Deadline_Variable (Parent_Type));
6572 if Present (Discriminant_Specifications (N)) then
6573 Push_Scope (Derived_Type);
6574 Check_Or_Process_Discriminants (N, Derived_Type);
6576 if Constraint_Present then
6578 Expand_To_Stored_Constraint
6580 Build_Discriminant_Constraints
6582 Subtype_Indication (Type_Definition (N)), True));
6587 elsif Constraint_Present then
6589 -- Build constrained subtype, copying the constraint, and derive
6590 -- from it to create a derived constrained type.
6593 Loc : constant Source_Ptr := Sloc (N);
6594 Anon : constant Entity_Id :=
6595 Make_Defining_Identifier (Loc,
6596 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6601 Make_Subtype_Declaration (Loc,
6602 Defining_Identifier => Anon,
6603 Subtype_Indication =>
6604 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6605 Insert_Before (N, Decl);
6608 Rewrite (Subtype_Indication (Type_Definition (N)),
6609 New_Occurrence_Of (Anon, Loc));
6610 Set_Analyzed (Derived_Type, False);
6616 -- By default, operations and private data are inherited from parent.
6617 -- However, in the presence of bound discriminants, a new corresponding
6618 -- record will be created, see below.
6620 Set_Has_Discriminants
6621 (Derived_Type, Has_Discriminants (Parent_Type));
6622 Set_Corresponding_Record_Type
6623 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6625 -- Is_Constrained is set according the parent subtype, but is set to
6626 -- False if the derived type is declared with new discriminants.
6630 (Is_Constrained (Parent_Type) or else Constraint_Present)
6631 and then not Present (Discriminant_Specifications (N)));
6633 if Constraint_Present then
6634 if not Has_Discriminants (Parent_Type) then
6635 Error_Msg_N ("untagged parent must have discriminants", N);
6637 elsif Present (Discriminant_Specifications (N)) then
6639 -- Verify that new discriminants are used to constrain old ones
6644 (Constraint (Subtype_Indication (Type_Definition (N)))));
6646 Old_Disc := First_Discriminant (Parent_Type);
6648 while Present (D_Constraint) loop
6649 if Nkind (D_Constraint) /= N_Discriminant_Association then
6651 -- Positional constraint. If it is a reference to a new
6652 -- discriminant, it constrains the corresponding old one.
6654 if Nkind (D_Constraint) = N_Identifier then
6655 New_Disc := First_Discriminant (Derived_Type);
6656 while Present (New_Disc) loop
6657 exit when Chars (New_Disc) = Chars (D_Constraint);
6658 Next_Discriminant (New_Disc);
6661 if Present (New_Disc) then
6662 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6666 Next_Discriminant (Old_Disc);
6668 -- if this is a named constraint, search by name for the old
6669 -- discriminants constrained by the new one.
6671 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6673 -- Find new discriminant with that name
6675 New_Disc := First_Discriminant (Derived_Type);
6676 while Present (New_Disc) loop
6678 Chars (New_Disc) = Chars (Expression (D_Constraint));
6679 Next_Discriminant (New_Disc);
6682 if Present (New_Disc) then
6684 -- Verify that new discriminant renames some discriminant
6685 -- of the parent type, and associate the new discriminant
6686 -- with one or more old ones that it renames.
6692 Selector := First (Selector_Names (D_Constraint));
6693 while Present (Selector) loop
6694 Old_Disc := First_Discriminant (Parent_Type);
6695 while Present (Old_Disc) loop
6696 exit when Chars (Old_Disc) = Chars (Selector);
6697 Next_Discriminant (Old_Disc);
6700 if Present (Old_Disc) then
6701 Set_Corresponding_Discriminant
6702 (New_Disc, Old_Disc);
6711 Next (D_Constraint);
6714 New_Disc := First_Discriminant (Derived_Type);
6715 while Present (New_Disc) loop
6716 if No (Corresponding_Discriminant (New_Disc)) then
6718 ("new discriminant& must constrain old one", N, New_Disc);
6721 Subtypes_Statically_Compatible
6723 Etype (Corresponding_Discriminant (New_Disc)))
6726 ("& not statically compatible with parent discriminant",
6730 Next_Discriminant (New_Disc);
6734 elsif Present (Discriminant_Specifications (N)) then
6736 ("missing discriminant constraint in untagged derivation", N);
6739 -- The entity chain of the derived type includes the new discriminants
6740 -- but shares operations with the parent.
6742 if Present (Discriminant_Specifications (N)) then
6743 Old_Disc := First_Discriminant (Parent_Type);
6744 while Present (Old_Disc) loop
6745 if No (Next_Entity (Old_Disc))
6746 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6749 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6753 Next_Discriminant (Old_Disc);
6757 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6758 if Has_Discriminants (Parent_Type) then
6759 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6760 Set_Discriminant_Constraint (
6761 Derived_Type, Discriminant_Constraint (Parent_Type));
6765 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6767 Set_Has_Completion (Derived_Type);
6769 if Corr_Decl_Needed then
6770 Set_Stored_Constraint (Derived_Type, New_Constraint);
6771 Insert_After (N, Corr_Decl);
6772 Analyze (Corr_Decl);
6773 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6775 end Build_Derived_Concurrent_Type;
6777 ------------------------------------
6778 -- Build_Derived_Enumeration_Type --
6779 ------------------------------------
6781 procedure Build_Derived_Enumeration_Type
6783 Parent_Type : Entity_Id;
6784 Derived_Type : Entity_Id)
6786 Loc : constant Source_Ptr := Sloc (N);
6787 Def : constant Node_Id := Type_Definition (N);
6788 Indic : constant Node_Id := Subtype_Indication (Def);
6789 Implicit_Base : Entity_Id;
6790 Literal : Entity_Id;
6791 New_Lit : Entity_Id;
6792 Literals_List : List_Id;
6793 Type_Decl : Node_Id;
6795 Rang_Expr : Node_Id;
6798 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6799 -- not have explicit literals lists we need to process types derived
6800 -- from them specially. This is handled by Derived_Standard_Character.
6801 -- If the parent type is a generic type, there are no literals either,
6802 -- and we construct the same skeletal representation as for the generic
6805 if Is_Standard_Character_Type (Parent_Type) then
6806 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6808 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6814 if Nkind (Indic) /= N_Subtype_Indication then
6816 Make_Attribute_Reference (Loc,
6817 Attribute_Name => Name_First,
6818 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6819 Set_Etype (Lo, Derived_Type);
6822 Make_Attribute_Reference (Loc,
6823 Attribute_Name => Name_Last,
6824 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6825 Set_Etype (Hi, Derived_Type);
6827 Set_Scalar_Range (Derived_Type,
6833 -- Analyze subtype indication and verify compatibility
6834 -- with parent type.
6836 if Base_Type (Process_Subtype (Indic, N)) /=
6837 Base_Type (Parent_Type)
6840 ("illegal constraint for formal discrete type", N);
6846 -- If a constraint is present, analyze the bounds to catch
6847 -- premature usage of the derived literals.
6849 if Nkind (Indic) = N_Subtype_Indication
6850 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6852 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6853 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6856 -- Introduce an implicit base type for the derived type even if there
6857 -- is no constraint attached to it, since this seems closer to the
6858 -- Ada semantics. Build a full type declaration tree for the derived
6859 -- type using the implicit base type as the defining identifier. The
6860 -- build a subtype declaration tree which applies the constraint (if
6861 -- any) have it replace the derived type declaration.
6863 Literal := First_Literal (Parent_Type);
6864 Literals_List := New_List;
6865 while Present (Literal)
6866 and then Ekind (Literal) = E_Enumeration_Literal
6868 -- Literals of the derived type have the same representation as
6869 -- those of the parent type, but this representation can be
6870 -- overridden by an explicit representation clause. Indicate
6871 -- that there is no explicit representation given yet. These
6872 -- derived literals are implicit operations of the new type,
6873 -- and can be overridden by explicit ones.
6875 if Nkind (Literal) = N_Defining_Character_Literal then
6877 Make_Defining_Character_Literal (Loc, Chars (Literal));
6879 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6882 Set_Ekind (New_Lit, E_Enumeration_Literal);
6883 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6884 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6885 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6886 Set_Alias (New_Lit, Literal);
6887 Set_Is_Known_Valid (New_Lit, True);
6889 Append (New_Lit, Literals_List);
6890 Next_Literal (Literal);
6894 Make_Defining_Identifier (Sloc (Derived_Type),
6895 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6897 -- Indicate the proper nature of the derived type. This must be done
6898 -- before analysis of the literals, to recognize cases when a literal
6899 -- may be hidden by a previous explicit function definition (cf.
6902 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6903 Set_Etype (Derived_Type, Implicit_Base);
6906 Make_Full_Type_Declaration (Loc,
6907 Defining_Identifier => Implicit_Base,
6908 Discriminant_Specifications => No_List,
6910 Make_Enumeration_Type_Definition (Loc, Literals_List));
6912 Mark_Rewrite_Insertion (Type_Decl);
6913 Insert_Before (N, Type_Decl);
6914 Analyze (Type_Decl);
6916 -- The anonymous base now has a full declaration, but this base
6917 -- is not a first subtype.
6919 Set_Is_First_Subtype (Implicit_Base, False);
6921 -- After the implicit base is analyzed its Etype needs to be changed
6922 -- to reflect the fact that it is derived from the parent type which
6923 -- was ignored during analysis. We also set the size at this point.
6925 Set_Etype (Implicit_Base, Parent_Type);
6927 Set_Size_Info (Implicit_Base, Parent_Type);
6928 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6929 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6931 -- Copy other flags from parent type
6933 Set_Has_Non_Standard_Rep
6934 (Implicit_Base, Has_Non_Standard_Rep
6936 Set_Has_Pragma_Ordered
6937 (Implicit_Base, Has_Pragma_Ordered
6939 Set_Has_Delayed_Freeze (Implicit_Base);
6941 -- Process the subtype indication including a validation check on the
6942 -- constraint, if any. If a constraint is given, its bounds must be
6943 -- implicitly converted to the new type.
6945 if Nkind (Indic) = N_Subtype_Indication then
6947 R : constant Node_Id :=
6948 Range_Expression (Constraint (Indic));
6951 if Nkind (R) = N_Range then
6952 Hi := Build_Scalar_Bound
6953 (High_Bound (R), Parent_Type, Implicit_Base);
6954 Lo := Build_Scalar_Bound
6955 (Low_Bound (R), Parent_Type, Implicit_Base);
6958 -- Constraint is a Range attribute. Replace with explicit
6959 -- mention of the bounds of the prefix, which must be a
6962 Analyze (Prefix (R));
6964 Convert_To (Implicit_Base,
6965 Make_Attribute_Reference (Loc,
6966 Attribute_Name => Name_Last,
6968 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6971 Convert_To (Implicit_Base,
6972 Make_Attribute_Reference (Loc,
6973 Attribute_Name => Name_First,
6975 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6982 (Type_High_Bound (Parent_Type),
6983 Parent_Type, Implicit_Base);
6986 (Type_Low_Bound (Parent_Type),
6987 Parent_Type, Implicit_Base);
6995 -- If we constructed a default range for the case where no range
6996 -- was given, then the expressions in the range must not freeze
6997 -- since they do not correspond to expressions in the source.
6998 -- However, if the type inherits predicates the expressions will
6999 -- be elaborated earlier and must freeze.
7001 if Nkind (Indic) /= N_Subtype_Indication
7002 and then not Has_Predicates (Derived_Type)
7004 Set_Must_Not_Freeze (Lo);
7005 Set_Must_Not_Freeze (Hi);
7006 Set_Must_Not_Freeze (Rang_Expr);
7010 Make_Subtype_Declaration (Loc,
7011 Defining_Identifier => Derived_Type,
7012 Subtype_Indication =>
7013 Make_Subtype_Indication (Loc,
7014 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
7016 Make_Range_Constraint (Loc,
7017 Range_Expression => Rang_Expr))));
7021 -- Propagate the aspects from the original type declaration to the
7022 -- declaration of the implicit base.
7024 Move_Aspects (From => Original_Node (N), To => Type_Decl);
7026 -- Apply a range check. Since this range expression doesn't have an
7027 -- Etype, we have to specifically pass the Source_Typ parameter. Is
7030 if Nkind (Indic) = N_Subtype_Indication then
7032 (Range_Expression (Constraint (Indic)), Parent_Type,
7033 Source_Typ => Entity (Subtype_Mark (Indic)));
7036 end Build_Derived_Enumeration_Type;
7038 --------------------------------
7039 -- Build_Derived_Numeric_Type --
7040 --------------------------------
7042 procedure Build_Derived_Numeric_Type
7044 Parent_Type : Entity_Id;
7045 Derived_Type : Entity_Id)
7047 Loc : constant Source_Ptr := Sloc (N);
7048 Tdef : constant Node_Id := Type_Definition (N);
7049 Indic : constant Node_Id := Subtype_Indication (Tdef);
7050 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7051 No_Constraint : constant Boolean := Nkind (Indic) /=
7052 N_Subtype_Indication;
7053 Implicit_Base : Entity_Id;
7059 -- Process the subtype indication including a validation check on
7060 -- the constraint if any.
7062 Discard_Node (Process_Subtype (Indic, N));
7064 -- Introduce an implicit base type for the derived type even if there
7065 -- is no constraint attached to it, since this seems closer to the Ada
7069 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
7071 Set_Etype (Implicit_Base, Parent_Base);
7072 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
7073 Set_Size_Info (Implicit_Base, Parent_Base);
7074 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
7075 Set_Parent (Implicit_Base, Parent (Derived_Type));
7076 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
7078 -- Set RM Size for discrete type or decimal fixed-point type
7079 -- Ordinary fixed-point is excluded, why???
7081 if Is_Discrete_Type (Parent_Base)
7082 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
7084 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
7087 Set_Has_Delayed_Freeze (Implicit_Base);
7089 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
7090 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
7092 Set_Scalar_Range (Implicit_Base,
7097 if Has_Infinities (Parent_Base) then
7098 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
7101 -- The Derived_Type, which is the entity of the declaration, is a
7102 -- subtype of the implicit base. Its Ekind is a subtype, even in the
7103 -- absence of an explicit constraint.
7105 Set_Etype (Derived_Type, Implicit_Base);
7107 -- If we did not have a constraint, then the Ekind is set from the
7108 -- parent type (otherwise Process_Subtype has set the bounds)
7110 if No_Constraint then
7111 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
7114 -- If we did not have a range constraint, then set the range from the
7115 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
7117 if No_Constraint or else not Has_Range_Constraint (Indic) then
7118 Set_Scalar_Range (Derived_Type,
7120 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
7121 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
7122 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7124 if Has_Infinities (Parent_Type) then
7125 Set_Includes_Infinities (Scalar_Range (Derived_Type));
7128 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
7131 Set_Is_Descendant_Of_Address (Derived_Type,
7132 Is_Descendant_Of_Address (Parent_Type));
7133 Set_Is_Descendant_Of_Address (Implicit_Base,
7134 Is_Descendant_Of_Address (Parent_Type));
7136 -- Set remaining type-specific fields, depending on numeric type
7138 if Is_Modular_Integer_Type (Parent_Type) then
7139 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
7141 Set_Non_Binary_Modulus
7142 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
7145 (Implicit_Base, Is_Known_Valid (Parent_Base));
7147 elsif Is_Floating_Point_Type (Parent_Type) then
7149 -- Digits of base type is always copied from the digits value of
7150 -- the parent base type, but the digits of the derived type will
7151 -- already have been set if there was a constraint present.
7153 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7154 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
7156 if No_Constraint then
7157 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
7160 elsif Is_Fixed_Point_Type (Parent_Type) then
7162 -- Small of base type and derived type are always copied from the
7163 -- parent base type, since smalls never change. The delta of the
7164 -- base type is also copied from the parent base type. However the
7165 -- delta of the derived type will have been set already if a
7166 -- constraint was present.
7168 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
7169 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
7170 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
7172 if No_Constraint then
7173 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
7176 -- The scale and machine radix in the decimal case are always
7177 -- copied from the parent base type.
7179 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
7180 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
7181 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
7183 Set_Machine_Radix_10
7184 (Derived_Type, Machine_Radix_10 (Parent_Base));
7185 Set_Machine_Radix_10
7186 (Implicit_Base, Machine_Radix_10 (Parent_Base));
7188 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7190 if No_Constraint then
7191 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
7194 -- the analysis of the subtype_indication sets the
7195 -- digits value of the derived type.
7202 if Is_Integer_Type (Parent_Type) then
7203 Set_Has_Shift_Operator
7204 (Implicit_Base, Has_Shift_Operator (Parent_Type));
7207 -- The type of the bounds is that of the parent type, and they
7208 -- must be converted to the derived type.
7210 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
7212 -- The implicit_base should be frozen when the derived type is frozen,
7213 -- but note that it is used in the conversions of the bounds. For fixed
7214 -- types we delay the determination of the bounds until the proper
7215 -- freezing point. For other numeric types this is rejected by GCC, for
7216 -- reasons that are currently unclear (???), so we choose to freeze the
7217 -- implicit base now. In the case of integers and floating point types
7218 -- this is harmless because subsequent representation clauses cannot
7219 -- affect anything, but it is still baffling that we cannot use the
7220 -- same mechanism for all derived numeric types.
7222 -- There is a further complication: actually some representation
7223 -- clauses can affect the implicit base type. For example, attribute
7224 -- definition clauses for stream-oriented attributes need to set the
7225 -- corresponding TSS entries on the base type, and this normally
7226 -- cannot be done after the base type is frozen, so the circuitry in
7227 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
7228 -- and not use Set_TSS in this case.
7230 -- There are also consequences for the case of delayed representation
7231 -- aspects for some cases. For example, a Size aspect is delayed and
7232 -- should not be evaluated to the freeze point. This early freezing
7233 -- means that the size attribute evaluation happens too early???
7235 if Is_Fixed_Point_Type (Parent_Type) then
7236 Conditional_Delay (Implicit_Base, Parent_Type);
7238 Freeze_Before (N, Implicit_Base);
7240 end Build_Derived_Numeric_Type;
7242 --------------------------------
7243 -- Build_Derived_Private_Type --
7244 --------------------------------
7246 procedure Build_Derived_Private_Type
7248 Parent_Type : Entity_Id;
7249 Derived_Type : Entity_Id;
7250 Is_Completion : Boolean;
7251 Derive_Subps : Boolean := True)
7253 Loc : constant Source_Ptr := Sloc (N);
7254 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7255 Par_Scope : constant Entity_Id := Scope (Par_Base);
7256 Full_N : constant Node_Id := New_Copy_Tree (N);
7257 Full_Der : Entity_Id := New_Copy (Derived_Type);
7260 procedure Build_Full_Derivation;
7261 -- Build full derivation, i.e. derive from the full view
7263 procedure Copy_And_Build;
7264 -- Copy derived type declaration, replace parent with its full view,
7265 -- and build derivation
7267 ---------------------------
7268 -- Build_Full_Derivation --
7269 ---------------------------
7271 procedure Build_Full_Derivation is
7273 -- If parent scope is not open, install the declarations
7275 if not In_Open_Scopes (Par_Scope) then
7276 Install_Private_Declarations (Par_Scope);
7277 Install_Visible_Declarations (Par_Scope);
7279 Uninstall_Declarations (Par_Scope);
7281 -- If parent scope is open and in another unit, and parent has a
7282 -- completion, then the derivation is taking place in the visible
7283 -- part of a child unit. In that case retrieve the full view of
7284 -- the parent momentarily.
7286 elsif not In_Same_Source_Unit (N, Parent_Type) then
7287 Full_P := Full_View (Parent_Type);
7288 Exchange_Declarations (Parent_Type);
7290 Exchange_Declarations (Full_P);
7292 -- Otherwise it is a local derivation
7297 end Build_Full_Derivation;
7299 --------------------
7300 -- Copy_And_Build --
7301 --------------------
7303 procedure Copy_And_Build is
7304 Full_Parent : Entity_Id := Parent_Type;
7307 -- If the parent is itself derived from another private type,
7308 -- installing the private declarations has not affected its
7309 -- privacy status, so use its own full view explicitly.
7311 if Is_Private_Type (Full_Parent)
7312 and then Present (Full_View (Full_Parent))
7314 Full_Parent := Full_View (Full_Parent);
7317 -- And its underlying full view if necessary
7319 if Is_Private_Type (Full_Parent)
7320 and then Present (Underlying_Full_View (Full_Parent))
7322 Full_Parent := Underlying_Full_View (Full_Parent);
7325 -- For record, access and most enumeration types, derivation from
7326 -- the full view requires a fully-fledged declaration. In the other
7327 -- cases, just use an itype.
7329 if Ekind (Full_Parent) in Record_Kind
7330 or else Ekind (Full_Parent) in Access_Kind
7332 (Ekind (Full_Parent) in Enumeration_Kind
7333 and then not Is_Standard_Character_Type (Full_Parent)
7334 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7336 -- Copy and adjust declaration to provide a completion for what
7337 -- is originally a private declaration. Indicate that full view
7338 -- is internally generated.
7340 Set_Comes_From_Source (Full_N, False);
7341 Set_Comes_From_Source (Full_Der, False);
7342 Set_Parent (Full_Der, Full_N);
7343 Set_Defining_Identifier (Full_N, Full_Der);
7345 -- If there are no constraints, adjust the subtype mark
7347 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7348 N_Subtype_Indication
7350 Set_Subtype_Indication
7351 (Type_Definition (Full_N),
7352 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7355 Insert_After (N, Full_N);
7357 -- Build full view of derived type from full view of parent which
7358 -- is now installed. Subprograms have been derived on the partial
7359 -- view, the completion does not derive them anew.
7361 if Ekind (Full_Parent) in Record_Kind then
7363 -- If parent type is tagged, the completion inherits the proper
7364 -- primitive operations.
7366 if Is_Tagged_Type (Parent_Type) then
7367 Build_Derived_Record_Type
7368 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7370 Build_Derived_Record_Type
7371 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7376 (Full_N, Full_Parent, Full_Der,
7377 Is_Completion => False, Derive_Subps => False);
7380 -- The full declaration has been introduced into the tree and
7381 -- processed in the step above. It should not be analyzed again
7382 -- (when encountered later in the current list of declarations)
7383 -- to prevent spurious name conflicts. The full entity remains
7386 Set_Analyzed (Full_N);
7390 Make_Defining_Identifier (Sloc (Derived_Type),
7391 Chars => Chars (Derived_Type));
7392 Set_Is_Itype (Full_Der);
7393 Set_Associated_Node_For_Itype (Full_Der, N);
7394 Set_Parent (Full_Der, N);
7396 (N, Full_Parent, Full_Der,
7397 Is_Completion => False, Derive_Subps => False);
7400 Set_Has_Private_Declaration (Full_Der);
7401 Set_Has_Private_Declaration (Derived_Type);
7403 Set_Scope (Full_Der, Scope (Derived_Type));
7404 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7405 Set_Has_Size_Clause (Full_Der, False);
7406 Set_Has_Alignment_Clause (Full_Der, False);
7407 Set_Has_Delayed_Freeze (Full_Der);
7408 Set_Is_Frozen (Full_Der, False);
7409 Set_Freeze_Node (Full_Der, Empty);
7410 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7411 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7413 -- The convention on the base type may be set in the private part
7414 -- and not propagated to the subtype until later, so we obtain the
7415 -- convention from the base type of the parent.
7417 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7420 -- Start of processing for Build_Derived_Private_Type
7423 if Is_Tagged_Type (Parent_Type) then
7424 Full_P := Full_View (Parent_Type);
7426 -- A type extension of a type with unknown discriminants is an
7427 -- indefinite type that the back-end cannot handle directly.
7428 -- We treat it as a private type, and build a completion that is
7429 -- derived from the full view of the parent, and hopefully has
7430 -- known discriminants.
7432 -- If the full view of the parent type has an underlying record view,
7433 -- use it to generate the underlying record view of this derived type
7434 -- (required for chains of derivations with unknown discriminants).
7436 -- Minor optimization: we avoid the generation of useless underlying
7437 -- record view entities if the private type declaration has unknown
7438 -- discriminants but its corresponding full view has no
7441 if Has_Unknown_Discriminants (Parent_Type)
7442 and then Present (Full_P)
7443 and then (Has_Discriminants (Full_P)
7444 or else Present (Underlying_Record_View (Full_P)))
7445 and then not In_Open_Scopes (Par_Scope)
7446 and then Expander_Active
7449 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7450 New_Ext : constant Node_Id :=
7452 (Record_Extension_Part (Type_Definition (N)));
7456 Build_Derived_Record_Type
7457 (N, Parent_Type, Derived_Type, Derive_Subps);
7459 -- Build anonymous completion, as a derivation from the full
7460 -- view of the parent. This is not a completion in the usual
7461 -- sense, because the current type is not private.
7464 Make_Full_Type_Declaration (Loc,
7465 Defining_Identifier => Full_Der,
7467 Make_Derived_Type_Definition (Loc,
7468 Subtype_Indication =>
7470 (Subtype_Indication (Type_Definition (N))),
7471 Record_Extension_Part => New_Ext));
7473 -- If the parent type has an underlying record view, use it
7474 -- here to build the new underlying record view.
7476 if Present (Underlying_Record_View (Full_P)) then
7478 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7480 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7481 Underlying_Record_View (Full_P));
7484 Install_Private_Declarations (Par_Scope);
7485 Install_Visible_Declarations (Par_Scope);
7486 Insert_Before (N, Decl);
7488 -- Mark entity as an underlying record view before analysis,
7489 -- to avoid generating the list of its primitive operations
7490 -- (which is not really required for this entity) and thus
7491 -- prevent spurious errors associated with missing overriding
7492 -- of abstract primitives (overridden only for Derived_Type).
7494 Set_Ekind (Full_Der, E_Record_Type);
7495 Set_Is_Underlying_Record_View (Full_Der);
7496 Set_Default_SSO (Full_Der);
7500 pragma Assert (Has_Discriminants (Full_Der)
7501 and then not Has_Unknown_Discriminants (Full_Der));
7503 Uninstall_Declarations (Par_Scope);
7505 -- Freeze the underlying record view, to prevent generation of
7506 -- useless dispatching information, which is simply shared with
7507 -- the real derived type.
7509 Set_Is_Frozen (Full_Der);
7511 -- If the derived type has access discriminants, create
7512 -- references to their anonymous types now, to prevent
7513 -- back-end problems when their first use is in generated
7514 -- bodies of primitives.
7520 E := First_Entity (Full_Der);
7522 while Present (E) loop
7523 if Ekind (E) = E_Discriminant
7524 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7526 Build_Itype_Reference (Etype (E), Decl);
7533 -- Set up links between real entity and underlying record view
7535 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7536 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7539 -- If discriminants are known, build derived record
7542 Build_Derived_Record_Type
7543 (N, Parent_Type, Derived_Type, Derive_Subps);
7548 elsif Has_Discriminants (Parent_Type) then
7550 -- Build partial view of derived type from partial view of parent.
7551 -- This must be done before building the full derivation because the
7552 -- second derivation will modify the discriminants of the first and
7553 -- the discriminants are chained with the rest of the components in
7554 -- the full derivation.
7556 Build_Derived_Record_Type
7557 (N, Parent_Type, Derived_Type, Derive_Subps);
7559 -- Build the full derivation if this is not the anonymous derived
7560 -- base type created by Build_Derived_Record_Type in the constrained
7561 -- case (see point 5. of its head comment) since we build it for the
7562 -- derived subtype. And skip it for protected types altogether, as
7563 -- gigi does not use these types directly.
7565 if Present (Full_View (Parent_Type))
7566 and then not Is_Itype (Derived_Type)
7567 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7570 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7572 Last_Discr : Entity_Id;
7575 -- If this is not a completion, construct the implicit full
7576 -- view by deriving from the full view of the parent type.
7577 -- But if this is a completion, the derived private type
7578 -- being built is a full view and the full derivation can
7579 -- only be its underlying full view.
7581 Build_Full_Derivation;
7583 if not Is_Completion then
7584 Set_Full_View (Derived_Type, Full_Der);
7586 Set_Underlying_Full_View (Derived_Type, Full_Der);
7587 Set_Is_Underlying_Full_View (Full_Der);
7590 if not Is_Base_Type (Derived_Type) then
7591 Set_Full_View (Der_Base, Base_Type (Full_Der));
7594 -- Copy the discriminant list from full view to the partial
7595 -- view (base type and its subtype). Gigi requires that the
7596 -- partial and full views have the same discriminants.
7598 -- Note that since the partial view points to discriminants
7599 -- in the full view, their scope will be that of the full
7600 -- view. This might cause some front end problems and need
7603 Discr := First_Discriminant (Base_Type (Full_Der));
7604 Set_First_Entity (Der_Base, Discr);
7607 Last_Discr := Discr;
7608 Next_Discriminant (Discr);
7609 exit when No (Discr);
7612 Set_Last_Entity (Der_Base, Last_Discr);
7613 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7614 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7616 Set_Stored_Constraint
7617 (Full_Der, Stored_Constraint (Derived_Type));
7621 elsif Present (Full_View (Parent_Type))
7622 and then Has_Discriminants (Full_View (Parent_Type))
7624 if Has_Unknown_Discriminants (Parent_Type)
7625 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7626 N_Subtype_Indication
7629 ("cannot constrain type with unknown discriminants",
7630 Subtype_Indication (Type_Definition (N)));
7634 -- If this is not a completion, construct the implicit full view by
7635 -- deriving from the full view of the parent type. But if this is a
7636 -- completion, the derived private type being built is a full view
7637 -- and the full derivation can only be its underlying full view.
7639 Build_Full_Derivation;
7641 if not Is_Completion then
7642 Set_Full_View (Derived_Type, Full_Der);
7644 Set_Underlying_Full_View (Derived_Type, Full_Der);
7645 Set_Is_Underlying_Full_View (Full_Der);
7648 -- In any case, the primitive operations are inherited from the
7649 -- parent type, not from the internal full view.
7651 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7653 if Derive_Subps then
7654 Derive_Subprograms (Parent_Type, Derived_Type);
7657 Set_Stored_Constraint (Derived_Type, No_Elist);
7659 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7662 -- Untagged type, No discriminants on either view
7664 if Nkind (Subtype_Indication (Type_Definition (N))) =
7665 N_Subtype_Indication
7668 ("illegal constraint on type without discriminants", N);
7671 if Present (Discriminant_Specifications (N))
7672 and then Present (Full_View (Parent_Type))
7673 and then not Is_Tagged_Type (Full_View (Parent_Type))
7675 Error_Msg_N ("cannot add discriminants to untagged type", N);
7678 Set_Stored_Constraint (Derived_Type, No_Elist);
7679 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7680 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7681 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7683 Set_Has_Controlled_Component
7684 (Derived_Type, Has_Controlled_Component
7687 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7689 if not Is_Controlled_Active (Parent_Type) then
7690 Set_Finalize_Storage_Only
7691 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7694 -- If this is not a completion, construct the implicit full view by
7695 -- deriving from the full view of the parent type.
7697 -- ??? If the parent is untagged private and its completion is
7698 -- tagged, this mechanism will not work because we cannot derive from
7699 -- the tagged full view unless we have an extension.
7701 if Present (Full_View (Parent_Type))
7702 and then not Is_Tagged_Type (Full_View (Parent_Type))
7703 and then not Is_Completion
7705 Build_Full_Derivation;
7706 Set_Full_View (Derived_Type, Full_Der);
7710 Set_Has_Unknown_Discriminants (Derived_Type,
7711 Has_Unknown_Discriminants (Parent_Type));
7713 if Is_Private_Type (Derived_Type) then
7714 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7717 -- If the parent base type is in scope, add the derived type to its
7718 -- list of private dependents, because its full view may become
7719 -- visible subsequently (in a nested private part, a body, or in a
7720 -- further child unit).
7722 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7723 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7725 -- Check for unusual case where a type completed by a private
7726 -- derivation occurs within a package nested in a child unit, and
7727 -- the parent is declared in an ancestor.
7729 if Is_Child_Unit (Scope (Current_Scope))
7730 and then Is_Completion
7731 and then In_Private_Part (Current_Scope)
7732 and then Scope (Parent_Type) /= Current_Scope
7734 -- Note that if the parent has a completion in the private part,
7735 -- (which is itself a derivation from some other private type)
7736 -- it is that completion that is visible, there is no full view
7737 -- available, and no special processing is needed.
7739 and then Present (Full_View (Parent_Type))
7741 -- In this case, the full view of the parent type will become
7742 -- visible in the body of the enclosing child, and only then will
7743 -- the current type be possibly non-private. Build an underlying
7744 -- full view that will be installed when the enclosing child body
7747 if Present (Underlying_Full_View (Derived_Type)) then
7748 Full_Der := Underlying_Full_View (Derived_Type);
7750 Build_Full_Derivation;
7751 Set_Underlying_Full_View (Derived_Type, Full_Der);
7752 Set_Is_Underlying_Full_View (Full_Der);
7755 -- The full view will be used to swap entities on entry/exit to
7756 -- the body, and must appear in the entity list for the package.
7758 Append_Entity (Full_Der, Scope (Derived_Type));
7761 end Build_Derived_Private_Type;
7763 -------------------------------
7764 -- Build_Derived_Record_Type --
7765 -------------------------------
7769 -- Ideally we would like to use the same model of type derivation for
7770 -- tagged and untagged record types. Unfortunately this is not quite
7771 -- possible because the semantics of representation clauses is different
7772 -- for tagged and untagged records under inheritance. Consider the
7775 -- type R (...) is [tagged] record ... end record;
7776 -- type T (...) is new R (...) [with ...];
7778 -- The representation clauses for T can specify a completely different
7779 -- record layout from R's. Hence the same component can be placed in two
7780 -- very different positions in objects of type T and R. If R and T are
7781 -- tagged types, representation clauses for T can only specify the layout
7782 -- of non inherited components, thus components that are common in R and T
7783 -- have the same position in objects of type R and T.
7785 -- This has two implications. The first is that the entire tree for R's
7786 -- declaration needs to be copied for T in the untagged case, so that T
7787 -- can be viewed as a record type of its own with its own representation
7788 -- clauses. The second implication is the way we handle discriminants.
7789 -- Specifically, in the untagged case we need a way to communicate to Gigi
7790 -- what are the real discriminants in the record, while for the semantics
7791 -- we need to consider those introduced by the user to rename the
7792 -- discriminants in the parent type. This is handled by introducing the
7793 -- notion of stored discriminants. See below for more.
7795 -- Fortunately the way regular components are inherited can be handled in
7796 -- the same way in tagged and untagged types.
7798 -- To complicate things a bit more the private view of a private extension
7799 -- cannot be handled in the same way as the full view (for one thing the
7800 -- semantic rules are somewhat different). We will explain what differs
7803 -- 2. DISCRIMINANTS UNDER INHERITANCE
7805 -- The semantic rules governing the discriminants of derived types are
7808 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7809 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7811 -- If parent type has discriminants, then the discriminants that are
7812 -- declared in the derived type are [3.4 (11)]:
7814 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7817 -- o Otherwise, each discriminant of the parent type (implicitly declared
7818 -- in the same order with the same specifications). In this case, the
7819 -- discriminants are said to be "inherited", or if unknown in the parent
7820 -- are also unknown in the derived type.
7822 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7824 -- o The parent subtype must be constrained;
7826 -- o If the parent type is not a tagged type, then each discriminant of
7827 -- the derived type must be used in the constraint defining a parent
7828 -- subtype. [Implementation note: This ensures that the new discriminant
7829 -- can share storage with an existing discriminant.]
7831 -- For the derived type each discriminant of the parent type is either
7832 -- inherited, constrained to equal some new discriminant of the derived
7833 -- type, or constrained to the value of an expression.
7835 -- When inherited or constrained to equal some new discriminant, the
7836 -- parent discriminant and the discriminant of the derived type are said
7839 -- If a discriminant of the parent type is constrained to a specific value
7840 -- in the derived type definition, then the discriminant is said to be
7841 -- "specified" by that derived type definition.
7843 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7845 -- We have spoken about stored discriminants in point 1 (introduction)
7846 -- above. There are two sort of stored discriminants: implicit and
7847 -- explicit. As long as the derived type inherits the same discriminants as
7848 -- the root record type, stored discriminants are the same as regular
7849 -- discriminants, and are said to be implicit. However, if any discriminant
7850 -- in the root type was renamed in the derived type, then the derived
7851 -- type will contain explicit stored discriminants. Explicit stored
7852 -- discriminants are discriminants in addition to the semantically visible
7853 -- discriminants defined for the derived type. Stored discriminants are
7854 -- used by Gigi to figure out what are the physical discriminants in
7855 -- objects of the derived type (see precise definition in einfo.ads).
7856 -- As an example, consider the following:
7858 -- type R (D1, D2, D3 : Int) is record ... end record;
7859 -- type T1 is new R;
7860 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7861 -- type T3 is new T2;
7862 -- type T4 (Y : Int) is new T3 (Y, 99);
7864 -- The following table summarizes the discriminants and stored
7865 -- discriminants in R and T1 through T4.
7867 -- Type Discrim Stored Discrim Comment
7868 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7869 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7870 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7871 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7872 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7874 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7875 -- find the corresponding discriminant in the parent type, while
7876 -- Original_Record_Component (abbreviated ORC below), the actual physical
7877 -- component that is renamed. Finally the field Is_Completely_Hidden
7878 -- (abbreviated ICH below) is set for all explicit stored discriminants
7879 -- (see einfo.ads for more info). For the above example this gives:
7881 -- Discrim CD ORC ICH
7882 -- ^^^^^^^ ^^ ^^^ ^^^
7883 -- D1 in R empty itself no
7884 -- D2 in R empty itself no
7885 -- D3 in R empty itself no
7887 -- D1 in T1 D1 in R itself no
7888 -- D2 in T1 D2 in R itself no
7889 -- D3 in T1 D3 in R itself no
7891 -- X1 in T2 D3 in T1 D3 in T2 no
7892 -- X2 in T2 D1 in T1 D1 in T2 no
7893 -- D1 in T2 empty itself yes
7894 -- D2 in T2 empty itself yes
7895 -- D3 in T2 empty itself yes
7897 -- X1 in T3 X1 in T2 D3 in T3 no
7898 -- X2 in T3 X2 in T2 D1 in T3 no
7899 -- D1 in T3 empty itself yes
7900 -- D2 in T3 empty itself yes
7901 -- D3 in T3 empty itself yes
7903 -- Y in T4 X1 in T3 D3 in T3 no
7904 -- D1 in T3 empty itself yes
7905 -- D2 in T3 empty itself yes
7906 -- D3 in T3 empty itself yes
7908 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7910 -- Type derivation for tagged types is fairly straightforward. If no
7911 -- discriminants are specified by the derived type, these are inherited
7912 -- from the parent. No explicit stored discriminants are ever necessary.
7913 -- The only manipulation that is done to the tree is that of adding a
7914 -- _parent field with parent type and constrained to the same constraint
7915 -- specified for the parent in the derived type definition. For instance:
7917 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7918 -- type T1 is new R with null record;
7919 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7921 -- are changed into:
7923 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7924 -- _parent : R (D1, D2, D3);
7927 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7928 -- _parent : T1 (X2, 88, X1);
7931 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7932 -- ORC and ICH fields are:
7934 -- Discrim CD ORC ICH
7935 -- ^^^^^^^ ^^ ^^^ ^^^
7936 -- D1 in R empty itself no
7937 -- D2 in R empty itself no
7938 -- D3 in R empty itself no
7940 -- D1 in T1 D1 in R D1 in R no
7941 -- D2 in T1 D2 in R D2 in R no
7942 -- D3 in T1 D3 in R D3 in R no
7944 -- X1 in T2 D3 in T1 D3 in R no
7945 -- X2 in T2 D1 in T1 D1 in R no
7947 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7949 -- Regardless of whether we dealing with a tagged or untagged type
7950 -- we will transform all derived type declarations of the form
7952 -- type T is new R (...) [with ...];
7954 -- subtype S is R (...);
7955 -- type T is new S [with ...];
7957 -- type BT is new R [with ...];
7958 -- subtype T is BT (...);
7960 -- That is, the base derived type is constrained only if it has no
7961 -- discriminants. The reason for doing this is that GNAT's semantic model
7962 -- assumes that a base type with discriminants is unconstrained.
7964 -- Note that, strictly speaking, the above transformation is not always
7965 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7967 -- procedure B34011A is
7968 -- type REC (D : integer := 0) is record
7973 -- type T6 is new Rec;
7974 -- function F return T6;
7979 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7982 -- The definition of Q6.U is illegal. However transforming Q6.U into
7984 -- type BaseU is new T6;
7985 -- subtype U is BaseU (Q6.F.I)
7987 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7988 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7989 -- the transformation described above.
7991 -- There is another instance where the above transformation is incorrect.
7995 -- type Base (D : Integer) is tagged null record;
7996 -- procedure P (X : Base);
7998 -- type Der is new Base (2) with null record;
7999 -- procedure P (X : Der);
8002 -- Then the above transformation turns this into
8004 -- type Der_Base is new Base with null record;
8005 -- -- procedure P (X : Base) is implicitly inherited here
8006 -- -- as procedure P (X : Der_Base).
8008 -- subtype Der is Der_Base (2);
8009 -- procedure P (X : Der);
8010 -- -- The overriding of P (X : Der_Base) is illegal since we
8011 -- -- have a parameter conformance problem.
8013 -- To get around this problem, after having semantically processed Der_Base
8014 -- and the rewritten subtype declaration for Der, we copy Der_Base field
8015 -- Discriminant_Constraint from Der so that when parameter conformance is
8016 -- checked when P is overridden, no semantic errors are flagged.
8018 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
8020 -- Regardless of whether we are dealing with a tagged or untagged type
8021 -- we will transform all derived type declarations of the form
8023 -- type R (D1, .., Dn : ...) is [tagged] record ...;
8024 -- type T is new R [with ...];
8026 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
8028 -- The reason for such transformation is that it allows us to implement a
8029 -- very clean form of component inheritance as explained below.
8031 -- Note that this transformation is not achieved by direct tree rewriting
8032 -- and manipulation, but rather by redoing the semantic actions that the
8033 -- above transformation will entail. This is done directly in routine
8034 -- Inherit_Components.
8036 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
8038 -- In both tagged and untagged derived types, regular non discriminant
8039 -- components are inherited in the derived type from the parent type. In
8040 -- the absence of discriminants component, inheritance is straightforward
8041 -- as components can simply be copied from the parent.
8043 -- If the parent has discriminants, inheriting components constrained with
8044 -- these discriminants requires caution. Consider the following example:
8046 -- type R (D1, D2 : Positive) is [tagged] record
8047 -- S : String (D1 .. D2);
8050 -- type T1 is new R [with null record];
8051 -- type T2 (X : positive) is new R (1, X) [with null record];
8053 -- As explained in 6. above, T1 is rewritten as
8054 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
8055 -- which makes the treatment for T1 and T2 identical.
8057 -- What we want when inheriting S, is that references to D1 and D2 in R are
8058 -- replaced with references to their correct constraints, i.e. D1 and D2 in
8059 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
8060 -- with either discriminant references in the derived type or expressions.
8061 -- This replacement is achieved as follows: before inheriting R's
8062 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
8063 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
8064 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
8065 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
8066 -- by String (1 .. X).
8068 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
8070 -- We explain here the rules governing private type extensions relevant to
8071 -- type derivation. These rules are explained on the following example:
8073 -- type D [(...)] is new A [(...)] with private; <-- partial view
8074 -- type D [(...)] is new P [(...)] with null record; <-- full view
8076 -- Type A is called the ancestor subtype of the private extension.
8077 -- Type P is the parent type of the full view of the private extension. It
8078 -- must be A or a type derived from A.
8080 -- The rules concerning the discriminants of private type extensions are
8083 -- o If a private extension inherits known discriminants from the ancestor
8084 -- subtype, then the full view must also inherit its discriminants from
8085 -- the ancestor subtype and the parent subtype of the full view must be
8086 -- constrained if and only if the ancestor subtype is constrained.
8088 -- o If a partial view has unknown discriminants, then the full view may
8089 -- define a definite or an indefinite subtype, with or without
8092 -- o If a partial view has neither known nor unknown discriminants, then
8093 -- the full view must define a definite subtype.
8095 -- o If the ancestor subtype of a private extension has constrained
8096 -- discriminants, then the parent subtype of the full view must impose a
8097 -- statically matching constraint on those discriminants.
8099 -- This means that only the following forms of private extensions are
8102 -- type D is new A with private; <-- partial view
8103 -- type D is new P with null record; <-- full view
8105 -- If A has no discriminants than P has no discriminants, otherwise P must
8106 -- inherit A's discriminants.
8108 -- type D is new A (...) with private; <-- partial view
8109 -- type D is new P (:::) with null record; <-- full view
8111 -- P must inherit A's discriminants and (...) and (:::) must statically
8114 -- subtype A is R (...);
8115 -- type D is new A with private; <-- partial view
8116 -- type D is new P with null record; <-- full view
8118 -- P must have inherited R's discriminants and must be derived from A or
8119 -- any of its subtypes.
8121 -- type D (..) is new A with private; <-- partial view
8122 -- type D (..) is new P [(:::)] with null record; <-- full view
8124 -- No specific constraints on P's discriminants or constraint (:::).
8125 -- Note that A can be unconstrained, but the parent subtype P must either
8126 -- be constrained or (:::) must be present.
8128 -- type D (..) is new A [(...)] with private; <-- partial view
8129 -- type D (..) is new P [(:::)] with null record; <-- full view
8131 -- P's constraints on A's discriminants must statically match those
8132 -- imposed by (...).
8134 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
8136 -- The full view of a private extension is handled exactly as described
8137 -- above. The model chose for the private view of a private extension is
8138 -- the same for what concerns discriminants (i.e. they receive the same
8139 -- treatment as in the tagged case). However, the private view of the
8140 -- private extension always inherits the components of the parent base,
8141 -- without replacing any discriminant reference. Strictly speaking this is
8142 -- incorrect. However, Gigi never uses this view to generate code so this
8143 -- is a purely semantic issue. In theory, a set of transformations similar
8144 -- to those given in 5. and 6. above could be applied to private views of
8145 -- private extensions to have the same model of component inheritance as
8146 -- for non private extensions. However, this is not done because it would
8147 -- further complicate private type processing. Semantically speaking, this
8148 -- leaves us in an uncomfortable situation. As an example consider:
8151 -- type R (D : integer) is tagged record
8152 -- S : String (1 .. D);
8154 -- procedure P (X : R);
8155 -- type T is new R (1) with private;
8157 -- type T is new R (1) with null record;
8160 -- This is transformed into:
8163 -- type R (D : integer) is tagged record
8164 -- S : String (1 .. D);
8166 -- procedure P (X : R);
8167 -- type T is new R (1) with private;
8169 -- type BaseT is new R with null record;
8170 -- subtype T is BaseT (1);
8173 -- (strictly speaking the above is incorrect Ada)
8175 -- From the semantic standpoint the private view of private extension T
8176 -- should be flagged as constrained since one can clearly have
8180 -- in a unit withing Pack. However, when deriving subprograms for the
8181 -- private view of private extension T, T must be seen as unconstrained
8182 -- since T has discriminants (this is a constraint of the current
8183 -- subprogram derivation model). Thus, when processing the private view of
8184 -- a private extension such as T, we first mark T as unconstrained, we
8185 -- process it, we perform program derivation and just before returning from
8186 -- Build_Derived_Record_Type we mark T as constrained.
8188 -- ??? Are there are other uncomfortable cases that we will have to
8191 -- 10. RECORD_TYPE_WITH_PRIVATE complications
8193 -- Types that are derived from a visible record type and have a private
8194 -- extension present other peculiarities. They behave mostly like private
8195 -- types, but if they have primitive operations defined, these will not
8196 -- have the proper signatures for further inheritance, because other
8197 -- primitive operations will use the implicit base that we define for
8198 -- private derivations below. This affect subprogram inheritance (see
8199 -- Derive_Subprograms for details). We also derive the implicit base from
8200 -- the base type of the full view, so that the implicit base is a record
8201 -- type and not another private type, This avoids infinite loops.
8203 procedure Build_Derived_Record_Type
8205 Parent_Type : Entity_Id;
8206 Derived_Type : Entity_Id;
8207 Derive_Subps : Boolean := True)
8209 Discriminant_Specs : constant Boolean :=
8210 Present (Discriminant_Specifications (N));
8211 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
8212 Loc : constant Source_Ptr := Sloc (N);
8213 Private_Extension : constant Boolean :=
8214 Nkind (N) = N_Private_Extension_Declaration;
8215 Assoc_List : Elist_Id;
8216 Constraint_Present : Boolean;
8218 Discrim : Entity_Id;
8220 Inherit_Discrims : Boolean := False;
8221 Last_Discrim : Entity_Id;
8222 New_Base : Entity_Id;
8224 New_Discrs : Elist_Id;
8225 New_Indic : Node_Id;
8226 Parent_Base : Entity_Id;
8227 Save_Etype : Entity_Id;
8228 Save_Discr_Constr : Elist_Id;
8229 Save_Next_Entity : Entity_Id;
8232 Discs : Elist_Id := New_Elmt_List;
8233 -- An empty Discs list means that there were no constraints in the
8234 -- subtype indication or that there was an error processing it.
8237 if Ekind (Parent_Type) = E_Record_Type_With_Private
8238 and then Present (Full_View (Parent_Type))
8239 and then Has_Discriminants (Parent_Type)
8241 Parent_Base := Base_Type (Full_View (Parent_Type));
8243 Parent_Base := Base_Type (Parent_Type);
8246 -- AI05-0115 : if this is a derivation from a private type in some
8247 -- other scope that may lead to invisible components for the derived
8248 -- type, mark it accordingly.
8250 if Is_Private_Type (Parent_Type) then
8251 if Scope (Parent_Type) = Scope (Derived_Type) then
8254 elsif In_Open_Scopes (Scope (Parent_Type))
8255 and then In_Private_Part (Scope (Parent_Type))
8260 Set_Has_Private_Ancestor (Derived_Type);
8264 Set_Has_Private_Ancestor
8265 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8268 -- Before we start the previously documented transformations, here is
8269 -- little fix for size and alignment of tagged types. Normally when we
8270 -- derive type D from type P, we copy the size and alignment of P as the
8271 -- default for D, and in the absence of explicit representation clauses
8272 -- for D, the size and alignment are indeed the same as the parent.
8274 -- But this is wrong for tagged types, since fields may be added, and
8275 -- the default size may need to be larger, and the default alignment may
8276 -- need to be larger.
8278 -- We therefore reset the size and alignment fields in the tagged case.
8279 -- Note that the size and alignment will in any case be at least as
8280 -- large as the parent type (since the derived type has a copy of the
8281 -- parent type in the _parent field)
8283 -- The type is also marked as being tagged here, which is needed when
8284 -- processing components with a self-referential anonymous access type
8285 -- in the call to Check_Anonymous_Access_Components below. Note that
8286 -- this flag is also set later on for completeness.
8289 Set_Is_Tagged_Type (Derived_Type);
8290 Init_Size_Align (Derived_Type);
8293 -- STEP 0a: figure out what kind of derived type declaration we have
8295 if Private_Extension then
8297 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8298 Set_Default_SSO (Derived_Type);
8301 Type_Def := Type_Definition (N);
8303 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8304 -- Parent_Base can be a private type or private extension. However,
8305 -- for tagged types with an extension the newly added fields are
8306 -- visible and hence the Derived_Type is always an E_Record_Type.
8307 -- (except that the parent may have its own private fields).
8308 -- For untagged types we preserve the Ekind of the Parent_Base.
8310 if Present (Record_Extension_Part (Type_Def)) then
8311 Set_Ekind (Derived_Type, E_Record_Type);
8312 Set_Default_SSO (Derived_Type);
8314 -- Create internal access types for components with anonymous
8317 if Ada_Version >= Ada_2005 then
8318 Check_Anonymous_Access_Components
8319 (N, Derived_Type, Derived_Type,
8320 Component_List (Record_Extension_Part (Type_Def)));
8324 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8328 -- Indic can either be an N_Identifier if the subtype indication
8329 -- contains no constraint or an N_Subtype_Indication if the subtype
8330 -- indication has a constraint.
8332 Indic := Subtype_Indication (Type_Def);
8333 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8335 -- Check that the type has visible discriminants. The type may be
8336 -- a private type with unknown discriminants whose full view has
8337 -- discriminants which are invisible.
8339 if Constraint_Present then
8340 if not Has_Discriminants (Parent_Base)
8342 (Has_Unknown_Discriminants (Parent_Base)
8343 and then Is_Private_Type (Parent_Base))
8346 ("invalid constraint: type has no discriminant",
8347 Constraint (Indic));
8349 Constraint_Present := False;
8350 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8352 elsif Is_Constrained (Parent_Type) then
8354 ("invalid constraint: parent type is already constrained",
8355 Constraint (Indic));
8357 Constraint_Present := False;
8358 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8362 -- STEP 0b: If needed, apply transformation given in point 5. above
8364 if not Private_Extension
8365 and then Has_Discriminants (Parent_Type)
8366 and then not Discriminant_Specs
8367 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8369 -- First, we must analyze the constraint (see comment in point 5.)
8370 -- The constraint may come from the subtype indication of the full
8373 if Constraint_Present then
8374 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8376 -- If there is no explicit constraint, there might be one that is
8377 -- inherited from a constrained parent type. In that case verify that
8378 -- it conforms to the constraint in the partial view. In perverse
8379 -- cases the parent subtypes of the partial and full view can have
8380 -- different constraints.
8382 elsif Present (Stored_Constraint (Parent_Type)) then
8383 New_Discrs := Stored_Constraint (Parent_Type);
8386 New_Discrs := No_Elist;
8389 if Has_Discriminants (Derived_Type)
8390 and then Has_Private_Declaration (Derived_Type)
8391 and then Present (Discriminant_Constraint (Derived_Type))
8392 and then Present (New_Discrs)
8394 -- Verify that constraints of the full view statically match
8395 -- those given in the partial view.
8401 C1 := First_Elmt (New_Discrs);
8402 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8403 while Present (C1) and then Present (C2) loop
8404 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8406 (Is_OK_Static_Expression (Node (C1))
8407 and then Is_OK_Static_Expression (Node (C2))
8409 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8414 if Constraint_Present then
8416 ("constraint not conformant to previous declaration",
8420 ("constraint of full view is incompatible "
8421 & "with partial view", N);
8431 -- Insert and analyze the declaration for the unconstrained base type
8433 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8436 Make_Full_Type_Declaration (Loc,
8437 Defining_Identifier => New_Base,
8439 Make_Derived_Type_Definition (Loc,
8440 Abstract_Present => Abstract_Present (Type_Def),
8441 Limited_Present => Limited_Present (Type_Def),
8442 Subtype_Indication =>
8443 New_Occurrence_Of (Parent_Base, Loc),
8444 Record_Extension_Part =>
8445 Relocate_Node (Record_Extension_Part (Type_Def)),
8446 Interface_List => Interface_List (Type_Def)));
8448 Set_Parent (New_Decl, Parent (N));
8449 Mark_Rewrite_Insertion (New_Decl);
8450 Insert_Before (N, New_Decl);
8452 -- In the extension case, make sure ancestor is frozen appropriately
8453 -- (see also non-discriminated case below).
8455 if Present (Record_Extension_Part (Type_Def))
8456 or else Is_Interface (Parent_Base)
8458 Freeze_Before (New_Decl, Parent_Type);
8461 -- Note that this call passes False for the Derive_Subps parameter
8462 -- because subprogram derivation is deferred until after creating
8463 -- the subtype (see below).
8466 (New_Decl, Parent_Base, New_Base,
8467 Is_Completion => False, Derive_Subps => False);
8469 -- ??? This needs re-examination to determine whether the
8470 -- above call can simply be replaced by a call to Analyze.
8472 Set_Analyzed (New_Decl);
8474 -- Insert and analyze the declaration for the constrained subtype
8476 if Constraint_Present then
8478 Make_Subtype_Indication (Loc,
8479 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8480 Constraint => Relocate_Node (Constraint (Indic)));
8484 Constr_List : constant List_Id := New_List;
8489 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8490 while Present (C) loop
8493 -- It is safe here to call New_Copy_Tree since we called
8494 -- Force_Evaluation on each constraint previously
8495 -- in Build_Discriminant_Constraints.
8497 Append (New_Copy_Tree (Expr), To => Constr_List);
8503 Make_Subtype_Indication (Loc,
8504 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8506 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8511 Make_Subtype_Declaration (Loc,
8512 Defining_Identifier => Derived_Type,
8513 Subtype_Indication => New_Indic));
8517 -- Derivation of subprograms must be delayed until the full subtype
8518 -- has been established, to ensure proper overriding of subprograms
8519 -- inherited by full types. If the derivations occurred as part of
8520 -- the call to Build_Derived_Type above, then the check for type
8521 -- conformance would fail because earlier primitive subprograms
8522 -- could still refer to the full type prior the change to the new
8523 -- subtype and hence would not match the new base type created here.
8524 -- Subprograms are not derived, however, when Derive_Subps is False
8525 -- (since otherwise there could be redundant derivations).
8527 if Derive_Subps then
8528 Derive_Subprograms (Parent_Type, Derived_Type);
8531 -- For tagged types the Discriminant_Constraint of the new base itype
8532 -- is inherited from the first subtype so that no subtype conformance
8533 -- problem arise when the first subtype overrides primitive
8534 -- operations inherited by the implicit base type.
8537 Set_Discriminant_Constraint
8538 (New_Base, Discriminant_Constraint (Derived_Type));
8544 -- If we get here Derived_Type will have no discriminants or it will be
8545 -- a discriminated unconstrained base type.
8547 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8551 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8552 -- The declaration of a specific descendant of an interface type
8553 -- freezes the interface type (RM 13.14).
8555 if not Private_Extension or else Is_Interface (Parent_Base) then
8556 Freeze_Before (N, Parent_Type);
8559 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8560 -- cannot be declared at a deeper level than its parent type is
8561 -- removed. The check on derivation within a generic body is also
8562 -- relaxed, but there's a restriction that a derived tagged type
8563 -- cannot be declared in a generic body if it's derived directly
8564 -- or indirectly from a formal type of that generic.
8566 if Ada_Version >= Ada_2005 then
8567 if Present (Enclosing_Generic_Body (Derived_Type)) then
8569 Ancestor_Type : Entity_Id;
8572 -- Check to see if any ancestor of the derived type is a
8575 Ancestor_Type := Parent_Type;
8576 while not Is_Generic_Type (Ancestor_Type)
8577 and then Etype (Ancestor_Type) /= Ancestor_Type
8579 Ancestor_Type := Etype (Ancestor_Type);
8582 -- If the derived type does have a formal type as an
8583 -- ancestor, then it's an error if the derived type is
8584 -- declared within the body of the generic unit that
8585 -- declares the formal type in its generic formal part. It's
8586 -- sufficient to check whether the ancestor type is declared
8587 -- inside the same generic body as the derived type (such as
8588 -- within a nested generic spec), in which case the
8589 -- derivation is legal. If the formal type is declared
8590 -- outside of that generic body, then it's guaranteed that
8591 -- the derived type is declared within the generic body of
8592 -- the generic unit declaring the formal type.
8594 if Is_Generic_Type (Ancestor_Type)
8595 and then Enclosing_Generic_Body (Ancestor_Type) /=
8596 Enclosing_Generic_Body (Derived_Type)
8599 ("parent type of& must not be descendant of formal type"
8600 & " of an enclosing generic body",
8601 Indic, Derived_Type);
8606 elsif Type_Access_Level (Derived_Type) /=
8607 Type_Access_Level (Parent_Type)
8608 and then not Is_Generic_Type (Derived_Type)
8610 if Is_Controlled (Parent_Type) then
8612 ("controlled type must be declared at the library level",
8616 ("type extension at deeper accessibility level than parent",
8622 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8625 and then GB /= Enclosing_Generic_Body (Parent_Base)
8628 ("parent type of& must not be outside generic body"
8630 Indic, Derived_Type);
8636 -- Ada 2005 (AI-251)
8638 if Ada_Version >= Ada_2005 and then Is_Tagged then
8640 -- "The declaration of a specific descendant of an interface type
8641 -- freezes the interface type" (RM 13.14).
8646 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8647 Iface := First (Interface_List (Type_Def));
8648 while Present (Iface) loop
8649 Freeze_Before (N, Etype (Iface));
8656 -- STEP 1b : preliminary cleanup of the full view of private types
8658 -- If the type is already marked as having discriminants, then it's the
8659 -- completion of a private type or private extension and we need to
8660 -- retain the discriminants from the partial view if the current
8661 -- declaration has Discriminant_Specifications so that we can verify
8662 -- conformance. However, we must remove any existing components that
8663 -- were inherited from the parent (and attached in Copy_And_Swap)
8664 -- because the full type inherits all appropriate components anyway, and
8665 -- we do not want the partial view's components interfering.
8667 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8668 Discrim := First_Discriminant (Derived_Type);
8670 Last_Discrim := Discrim;
8671 Next_Discriminant (Discrim);
8672 exit when No (Discrim);
8675 Set_Last_Entity (Derived_Type, Last_Discrim);
8677 -- In all other cases wipe out the list of inherited components (even
8678 -- inherited discriminants), it will be properly rebuilt here.
8681 Set_First_Entity (Derived_Type, Empty);
8682 Set_Last_Entity (Derived_Type, Empty);
8685 -- STEP 1c: Initialize some flags for the Derived_Type
8687 -- The following flags must be initialized here so that
8688 -- Process_Discriminants can check that discriminants of tagged types do
8689 -- not have a default initial value and that access discriminants are
8690 -- only specified for limited records. For completeness, these flags are
8691 -- also initialized along with all the other flags below.
8693 -- AI-419: Limitedness is not inherited from an interface parent, so to
8694 -- be limited in that case the type must be explicitly declared as
8695 -- limited. However, task and protected interfaces are always limited.
8697 if Limited_Present (Type_Def) then
8698 Set_Is_Limited_Record (Derived_Type);
8700 elsif Is_Limited_Record (Parent_Type)
8701 or else (Present (Full_View (Parent_Type))
8702 and then Is_Limited_Record (Full_View (Parent_Type)))
8704 if not Is_Interface (Parent_Type)
8705 or else Is_Synchronized_Interface (Parent_Type)
8706 or else Is_Protected_Interface (Parent_Type)
8707 or else Is_Task_Interface (Parent_Type)
8709 Set_Is_Limited_Record (Derived_Type);
8713 -- STEP 2a: process discriminants of derived type if any
8715 Push_Scope (Derived_Type);
8717 if Discriminant_Specs then
8718 Set_Has_Unknown_Discriminants (Derived_Type, False);
8720 -- The following call initializes fields Has_Discriminants and
8721 -- Discriminant_Constraint, unless we are processing the completion
8722 -- of a private type declaration.
8724 Check_Or_Process_Discriminants (N, Derived_Type);
8726 -- For untagged types, the constraint on the Parent_Type must be
8727 -- present and is used to rename the discriminants.
8729 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8730 Error_Msg_N ("untagged parent must have discriminants", Indic);
8732 elsif not Is_Tagged and then not Constraint_Present then
8734 ("discriminant constraint needed for derived untagged records",
8737 -- Otherwise the parent subtype must be constrained unless we have a
8738 -- private extension.
8740 elsif not Constraint_Present
8741 and then not Private_Extension
8742 and then not Is_Constrained (Parent_Type)
8745 ("unconstrained type not allowed in this context", Indic);
8747 elsif Constraint_Present then
8748 -- The following call sets the field Corresponding_Discriminant
8749 -- for the discriminants in the Derived_Type.
8751 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8753 -- For untagged types all new discriminants must rename
8754 -- discriminants in the parent. For private extensions new
8755 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8757 Discrim := First_Discriminant (Derived_Type);
8758 while Present (Discrim) loop
8760 and then No (Corresponding_Discriminant (Discrim))
8763 ("new discriminants must constrain old ones", Discrim);
8765 elsif Private_Extension
8766 and then Present (Corresponding_Discriminant (Discrim))
8769 ("only static constraints allowed for parent"
8770 & " discriminants in the partial view", Indic);
8774 -- If a new discriminant is used in the constraint, then its
8775 -- subtype must be statically compatible with the parent
8776 -- discriminant's subtype (3.7(15)).
8778 -- However, if the record contains an array constrained by
8779 -- the discriminant but with some different bound, the compiler
8780 -- tries to create a smaller range for the discriminant type.
8781 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8782 -- the discriminant type is a scalar type, the check must use
8783 -- the original discriminant type in the parent declaration.
8786 Corr_Disc : constant Entity_Id :=
8787 Corresponding_Discriminant (Discrim);
8788 Disc_Type : constant Entity_Id := Etype (Discrim);
8789 Corr_Type : Entity_Id;
8792 if Present (Corr_Disc) then
8793 if Is_Scalar_Type (Disc_Type) then
8795 Entity (Discriminant_Type (Parent (Corr_Disc)));
8797 Corr_Type := Etype (Corr_Disc);
8801 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8804 ("subtype must be compatible "
8805 & "with parent discriminant",
8811 Next_Discriminant (Discrim);
8814 -- Check whether the constraints of the full view statically
8815 -- match those imposed by the parent subtype [7.3(13)].
8817 if Present (Stored_Constraint (Derived_Type)) then
8822 C1 := First_Elmt (Discs);
8823 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8824 while Present (C1) and then Present (C2) loop
8826 Fully_Conformant_Expressions (Node (C1), Node (C2))
8829 ("not conformant with previous declaration",
8840 -- STEP 2b: No new discriminants, inherit discriminants if any
8843 if Private_Extension then
8844 Set_Has_Unknown_Discriminants
8846 Has_Unknown_Discriminants (Parent_Type)
8847 or else Unknown_Discriminants_Present (N));
8849 -- The partial view of the parent may have unknown discriminants,
8850 -- but if the full view has discriminants and the parent type is
8851 -- in scope they must be inherited.
8853 elsif Has_Unknown_Discriminants (Parent_Type)
8855 (not Has_Discriminants (Parent_Type)
8856 or else not In_Open_Scopes (Scope (Parent_Type)))
8858 Set_Has_Unknown_Discriminants (Derived_Type);
8861 if not Has_Unknown_Discriminants (Derived_Type)
8862 and then not Has_Unknown_Discriminants (Parent_Base)
8863 and then Has_Discriminants (Parent_Type)
8865 Inherit_Discrims := True;
8866 Set_Has_Discriminants
8867 (Derived_Type, True);
8868 Set_Discriminant_Constraint
8869 (Derived_Type, Discriminant_Constraint (Parent_Base));
8872 -- The following test is true for private types (remember
8873 -- transformation 5. is not applied to those) and in an error
8876 if Constraint_Present then
8877 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8880 -- For now mark a new derived type as constrained only if it has no
8881 -- discriminants. At the end of Build_Derived_Record_Type we properly
8882 -- set this flag in the case of private extensions. See comments in
8883 -- point 9. just before body of Build_Derived_Record_Type.
8887 not (Inherit_Discrims
8888 or else Has_Unknown_Discriminants (Derived_Type)));
8891 -- STEP 3: initialize fields of derived type
8893 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8894 Set_Stored_Constraint (Derived_Type, No_Elist);
8896 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8897 -- but cannot be interfaces
8899 if not Private_Extension
8900 and then Ekind (Derived_Type) /= E_Private_Type
8901 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8903 if Interface_Present (Type_Def) then
8904 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8907 Set_Interfaces (Derived_Type, No_Elist);
8910 -- Fields inherited from the Parent_Type
8912 Set_Has_Specified_Layout
8913 (Derived_Type, Has_Specified_Layout (Parent_Type));
8914 Set_Is_Limited_Composite
8915 (Derived_Type, Is_Limited_Composite (Parent_Type));
8916 Set_Is_Private_Composite
8917 (Derived_Type, Is_Private_Composite (Parent_Type));
8919 if Is_Tagged_Type (Parent_Type) then
8920 Set_No_Tagged_Streams_Pragma
8921 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8924 -- Fields inherited from the Parent_Base
8926 Set_Has_Controlled_Component
8927 (Derived_Type, Has_Controlled_Component (Parent_Base));
8928 Set_Has_Non_Standard_Rep
8929 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8930 Set_Has_Primitive_Operations
8931 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8933 -- Fields inherited from the Parent_Base in the non-private case
8935 if Ekind (Derived_Type) = E_Record_Type then
8936 Set_Has_Complex_Representation
8937 (Derived_Type, Has_Complex_Representation (Parent_Base));
8940 -- Fields inherited from the Parent_Base for record types
8942 if Is_Record_Type (Derived_Type) then
8944 Parent_Full : Entity_Id;
8947 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8948 -- Parent_Base can be a private type or private extension. Go
8949 -- to the full view here to get the E_Record_Type specific flags.
8951 if Present (Full_View (Parent_Base)) then
8952 Parent_Full := Full_View (Parent_Base);
8954 Parent_Full := Parent_Base;
8957 Set_OK_To_Reorder_Components
8958 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8962 -- Set fields for private derived types
8964 if Is_Private_Type (Derived_Type) then
8965 Set_Depends_On_Private (Derived_Type, True);
8966 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8968 -- Inherit fields from non private record types. If this is the
8969 -- completion of a derivation from a private type, the parent itself
8970 -- is private, and the attributes come from its full view, which must
8974 if Is_Private_Type (Parent_Base)
8975 and then not Is_Record_Type (Parent_Base)
8977 Set_Component_Alignment
8978 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8980 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8982 Set_Component_Alignment
8983 (Derived_Type, Component_Alignment (Parent_Base));
8985 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8989 -- Set fields for tagged types
8992 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8994 -- All tagged types defined in Ada.Finalization are controlled
8996 if Chars (Scope (Derived_Type)) = Name_Finalization
8997 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8998 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
9000 Set_Is_Controlled (Derived_Type);
9002 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
9005 -- Minor optimization: there is no need to generate the class-wide
9006 -- entity associated with an underlying record view.
9008 if not Is_Underlying_Record_View (Derived_Type) then
9009 Make_Class_Wide_Type (Derived_Type);
9012 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
9014 if Has_Discriminants (Derived_Type)
9015 and then Constraint_Present
9017 Set_Stored_Constraint
9018 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
9021 if Ada_Version >= Ada_2005 then
9023 Ifaces_List : Elist_Id;
9026 -- Checks rules 3.9.4 (13/2 and 14/2)
9028 if Comes_From_Source (Derived_Type)
9029 and then not Is_Private_Type (Derived_Type)
9030 and then Is_Interface (Parent_Type)
9031 and then not Is_Interface (Derived_Type)
9033 if Is_Task_Interface (Parent_Type) then
9035 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
9038 elsif Is_Protected_Interface (Parent_Type) then
9040 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
9045 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
9047 Check_Interfaces (N, Type_Def);
9049 -- Ada 2005 (AI-251): Collect the list of progenitors that are
9050 -- not already in the parents.
9054 Ifaces_List => Ifaces_List,
9055 Exclude_Parents => True);
9057 Set_Interfaces (Derived_Type, Ifaces_List);
9059 -- If the derived type is the anonymous type created for
9060 -- a declaration whose parent has a constraint, propagate
9061 -- the interface list to the source type. This must be done
9062 -- prior to the completion of the analysis of the source type
9063 -- because the components in the extension may contain current
9064 -- instances whose legality depends on some ancestor.
9066 if Is_Itype (Derived_Type) then
9068 Def : constant Node_Id :=
9069 Associated_Node_For_Itype (Derived_Type);
9072 and then Nkind (Def) = N_Full_Type_Declaration
9075 (Defining_Identifier (Def), Ifaces_List);
9080 -- A type extension is automatically Ghost when one of its
9081 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
9082 -- also inherited when the parent type is Ghost, but this is
9083 -- done in Build_Derived_Type as the mechanism also handles
9084 -- untagged derivations.
9086 if Implements_Ghost_Interface (Derived_Type) then
9087 Set_Is_Ghost_Entity (Derived_Type);
9093 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
9094 Set_Has_Non_Standard_Rep
9095 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
9098 -- STEP 4: Inherit components from the parent base and constrain them.
9099 -- Apply the second transformation described in point 6. above.
9101 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
9102 or else not Has_Discriminants (Parent_Type)
9103 or else not Is_Constrained (Parent_Type)
9107 Constrs := Discriminant_Constraint (Parent_Type);
9112 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
9114 -- STEP 5a: Copy the parent record declaration for untagged types
9116 Set_Has_Implicit_Dereference
9117 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
9119 if not Is_Tagged then
9121 -- Discriminant_Constraint (Derived_Type) has been properly
9122 -- constructed. Save it and temporarily set it to Empty because we
9123 -- do not want the call to New_Copy_Tree below to mess this list.
9125 if Has_Discriminants (Derived_Type) then
9126 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
9127 Set_Discriminant_Constraint (Derived_Type, No_Elist);
9129 Save_Discr_Constr := No_Elist;
9132 -- Save the Etype field of Derived_Type. It is correctly set now,
9133 -- but the call to New_Copy tree may remap it to point to itself,
9134 -- which is not what we want. Ditto for the Next_Entity field.
9136 Save_Etype := Etype (Derived_Type);
9137 Save_Next_Entity := Next_Entity (Derived_Type);
9139 -- Assoc_List maps all stored discriminants in the Parent_Base to
9140 -- stored discriminants in the Derived_Type. It is fundamental that
9141 -- no types or itypes with discriminants other than the stored
9142 -- discriminants appear in the entities declared inside
9143 -- Derived_Type, since the back end cannot deal with it.
9147 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
9149 -- Restore the fields saved prior to the New_Copy_Tree call
9150 -- and compute the stored constraint.
9152 Set_Etype (Derived_Type, Save_Etype);
9153 Set_Next_Entity (Derived_Type, Save_Next_Entity);
9155 if Has_Discriminants (Derived_Type) then
9156 Set_Discriminant_Constraint
9157 (Derived_Type, Save_Discr_Constr);
9158 Set_Stored_Constraint
9159 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
9160 Replace_Components (Derived_Type, New_Decl);
9163 -- Insert the new derived type declaration
9165 Rewrite (N, New_Decl);
9167 -- STEP 5b: Complete the processing for record extensions in generics
9169 -- There is no completion for record extensions declared in the
9170 -- parameter part of a generic, so we need to complete processing for
9171 -- these generic record extensions here. The Record_Type_Definition call
9172 -- will change the Ekind of the components from E_Void to E_Component.
9174 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
9175 Record_Type_Definition (Empty, Derived_Type);
9177 -- STEP 5c: Process the record extension for non private tagged types
9179 elsif not Private_Extension then
9180 Expand_Record_Extension (Derived_Type, Type_Def);
9182 -- Note : previously in ASIS mode we set the Parent_Subtype of the
9183 -- derived type to propagate some semantic information. This led
9184 -- to other ASIS failures and has been removed.
9186 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
9187 -- implemented interfaces if we are in expansion mode
9190 and then Has_Interfaces (Derived_Type)
9192 Add_Interface_Tag_Components (N, Derived_Type);
9195 -- Analyze the record extension
9197 Record_Type_Definition
9198 (Record_Extension_Part (Type_Def), Derived_Type);
9203 -- Nothing else to do if there is an error in the derivation.
9204 -- An unusual case: the full view may be derived from a type in an
9205 -- instance, when the partial view was used illegally as an actual
9206 -- in that instance, leading to a circular definition.
9208 if Etype (Derived_Type) = Any_Type
9209 or else Etype (Parent_Type) = Derived_Type
9214 -- Set delayed freeze and then derive subprograms, we need to do
9215 -- this in this order so that derived subprograms inherit the
9216 -- derived freeze if necessary.
9218 Set_Has_Delayed_Freeze (Derived_Type);
9220 if Derive_Subps then
9221 Derive_Subprograms (Parent_Type, Derived_Type);
9224 -- If we have a private extension which defines a constrained derived
9225 -- type mark as constrained here after we have derived subprograms. See
9226 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9228 if Private_Extension and then Inherit_Discrims then
9229 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9230 Set_Is_Constrained (Derived_Type, True);
9231 Set_Discriminant_Constraint (Derived_Type, Discs);
9233 elsif Is_Constrained (Parent_Type) then
9235 (Derived_Type, True);
9236 Set_Discriminant_Constraint
9237 (Derived_Type, Discriminant_Constraint (Parent_Type));
9241 -- Update the class-wide type, which shares the now-completed entity
9242 -- list with its specific type. In case of underlying record views,
9243 -- we do not generate the corresponding class wide entity.
9246 and then not Is_Underlying_Record_View (Derived_Type)
9249 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9251 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9254 Check_Function_Writable_Actuals (N);
9255 end Build_Derived_Record_Type;
9257 ------------------------
9258 -- Build_Derived_Type --
9259 ------------------------
9261 procedure Build_Derived_Type
9263 Parent_Type : Entity_Id;
9264 Derived_Type : Entity_Id;
9265 Is_Completion : Boolean;
9266 Derive_Subps : Boolean := True)
9268 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9271 -- Set common attributes
9273 Set_Scope (Derived_Type, Current_Scope);
9275 Set_Etype (Derived_Type, Parent_Base);
9276 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9277 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9279 Set_Size_Info (Derived_Type, Parent_Type);
9280 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9281 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9282 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9284 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9285 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9287 if Is_Tagged_Type (Derived_Type) then
9288 Set_No_Tagged_Streams_Pragma
9289 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9292 -- If the parent has primitive routines, set the derived type link
9294 if Has_Primitive_Operations (Parent_Type) then
9295 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9298 -- If the parent type is a private subtype, the convention on the base
9299 -- type may be set in the private part, and not propagated to the
9300 -- subtype until later, so we obtain the convention from the base type.
9302 Set_Convention (Derived_Type, Convention (Parent_Base));
9304 -- Set SSO default for record or array type
9306 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9307 and then Is_Base_Type (Derived_Type)
9309 Set_Default_SSO (Derived_Type);
9312 -- A derived type inherits the Default_Initial_Condition pragma coming
9313 -- from any parent type within the derivation chain.
9315 if Has_DIC (Parent_Type) then
9316 Set_Has_Inherited_DIC (Derived_Type);
9319 -- A derived type inherits any class-wide invariants coming from a
9320 -- parent type or an interface. Note that the invariant procedure of
9321 -- the parent type should not be inherited because the derived type may
9322 -- define invariants of its own.
9324 if not Is_Interface (Derived_Type) then
9325 if Has_Inherited_Invariants (Parent_Type)
9326 or else Has_Inheritable_Invariants (Parent_Type)
9328 Set_Has_Inherited_Invariants (Derived_Type);
9330 elsif Is_Concurrent_Type (Derived_Type)
9331 or else Is_Tagged_Type (Derived_Type)
9336 Iface_Elmt : Elmt_Id;
9341 Ifaces_List => Ifaces,
9342 Exclude_Parents => True);
9344 if Present (Ifaces) then
9345 Iface_Elmt := First_Elmt (Ifaces);
9346 while Present (Iface_Elmt) loop
9347 Iface := Node (Iface_Elmt);
9349 if Has_Inheritable_Invariants (Iface) then
9350 Set_Has_Inherited_Invariants (Derived_Type);
9354 Next_Elmt (Iface_Elmt);
9361 -- We similarly inherit predicates. Note that for scalar derived types
9362 -- the predicate is inherited from the first subtype, and not from its
9363 -- (anonymous) base type.
9365 if Has_Predicates (Parent_Type)
9366 or else Has_Predicates (First_Subtype (Parent_Type))
9368 Set_Has_Predicates (Derived_Type);
9371 -- The derived type inherits the representation clauses of the parent
9373 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9375 -- If the parent type has delayed rep aspects, then mark the derived
9376 -- type as possibly inheriting a delayed rep aspect.
9378 if Has_Delayed_Rep_Aspects (Parent_Type) then
9379 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9382 -- A derived type becomes Ghost when its parent type is also Ghost
9383 -- (SPARK RM 6.9(9)). Note that the Ghost-related attributes are not
9384 -- directly inherited because the Ghost policy in effect may differ.
9386 if Is_Ghost_Entity (Parent_Type) then
9387 Set_Is_Ghost_Entity (Derived_Type);
9390 -- Type dependent processing
9392 case Ekind (Parent_Type) is
9393 when Numeric_Kind =>
9394 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9397 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9399 when Class_Wide_Kind
9403 Build_Derived_Record_Type
9404 (N, Parent_Type, Derived_Type, Derive_Subps);
9407 when Enumeration_Kind =>
9408 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9411 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9413 when Incomplete_Or_Private_Kind =>
9414 Build_Derived_Private_Type
9415 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9417 -- For discriminated types, the derivation includes deriving
9418 -- primitive operations. For others it is done below.
9420 if Is_Tagged_Type (Parent_Type)
9421 or else Has_Discriminants (Parent_Type)
9422 or else (Present (Full_View (Parent_Type))
9423 and then Has_Discriminants (Full_View (Parent_Type)))
9428 when Concurrent_Kind =>
9429 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9432 raise Program_Error;
9435 -- Nothing more to do if some error occurred
9437 if Etype (Derived_Type) = Any_Type then
9441 -- Set delayed freeze and then derive subprograms, we need to do this
9442 -- in this order so that derived subprograms inherit the derived freeze
9445 Set_Has_Delayed_Freeze (Derived_Type);
9447 if Derive_Subps then
9448 Derive_Subprograms (Parent_Type, Derived_Type);
9451 Set_Has_Primitive_Operations
9452 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9453 end Build_Derived_Type;
9455 -----------------------
9456 -- Build_Discriminal --
9457 -----------------------
9459 procedure Build_Discriminal (Discrim : Entity_Id) is
9460 D_Minal : Entity_Id;
9461 CR_Disc : Entity_Id;
9464 -- A discriminal has the same name as the discriminant
9466 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9468 Set_Ekind (D_Minal, E_In_Parameter);
9469 Set_Mechanism (D_Minal, Default_Mechanism);
9470 Set_Etype (D_Minal, Etype (Discrim));
9471 Set_Scope (D_Minal, Current_Scope);
9472 Set_Parent (D_Minal, Parent (Discrim));
9474 Set_Discriminal (Discrim, D_Minal);
9475 Set_Discriminal_Link (D_Minal, Discrim);
9477 -- For task types, build at once the discriminants of the corresponding
9478 -- record, which are needed if discriminants are used in entry defaults
9479 -- and in family bounds.
9481 if Is_Concurrent_Type (Current_Scope)
9483 Is_Limited_Type (Current_Scope)
9485 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9487 Set_Ekind (CR_Disc, E_In_Parameter);
9488 Set_Mechanism (CR_Disc, Default_Mechanism);
9489 Set_Etype (CR_Disc, Etype (Discrim));
9490 Set_Scope (CR_Disc, Current_Scope);
9491 Set_Discriminal_Link (CR_Disc, Discrim);
9492 Set_CR_Discriminant (Discrim, CR_Disc);
9494 end Build_Discriminal;
9496 ------------------------------------
9497 -- Build_Discriminant_Constraints --
9498 ------------------------------------
9500 function Build_Discriminant_Constraints
9503 Derived_Def : Boolean := False) return Elist_Id
9505 C : constant Node_Id := Constraint (Def);
9506 Nb_Discr : constant Nat := Number_Discriminants (T);
9508 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9509 -- Saves the expression corresponding to a given discriminant in T
9511 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9512 -- Return the Position number within array Discr_Expr of a discriminant
9513 -- D within the discriminant list of the discriminated type T.
9515 procedure Process_Discriminant_Expression
9518 -- If this is a discriminant constraint on a partial view, do not
9519 -- generate an overflow check on the discriminant expression. The check
9520 -- will be generated when constraining the full view. Otherwise the
9521 -- backend creates duplicate symbols for the temporaries corresponding
9522 -- to the expressions to be checked, causing spurious assembler errors.
9528 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9532 Disc := First_Discriminant (T);
9533 for J in Discr_Expr'Range loop
9538 Next_Discriminant (Disc);
9541 -- Note: Since this function is called on discriminants that are
9542 -- known to belong to the discriminated type, falling through the
9543 -- loop with no match signals an internal compiler error.
9545 raise Program_Error;
9548 -------------------------------------
9549 -- Process_Discriminant_Expression --
9550 -------------------------------------
9552 procedure Process_Discriminant_Expression
9556 BDT : constant Entity_Id := Base_Type (Etype (D));
9559 -- If this is a discriminant constraint on a partial view, do
9560 -- not generate an overflow on the discriminant expression. The
9561 -- check will be generated when constraining the full view.
9563 if Is_Private_Type (T)
9564 and then Present (Full_View (T))
9566 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9568 Analyze_And_Resolve (Expr, BDT);
9570 end Process_Discriminant_Expression;
9572 -- Declarations local to Build_Discriminant_Constraints
9576 Elist : constant Elist_Id := New_Elmt_List;
9584 Discrim_Present : Boolean := False;
9586 -- Start of processing for Build_Discriminant_Constraints
9589 -- The following loop will process positional associations only.
9590 -- For a positional association, the (single) discriminant is
9591 -- implicitly specified by position, in textual order (RM 3.7.2).
9593 Discr := First_Discriminant (T);
9594 Constr := First (Constraints (C));
9595 for D in Discr_Expr'Range loop
9596 exit when Nkind (Constr) = N_Discriminant_Association;
9599 Error_Msg_N ("too few discriminants given in constraint", C);
9600 return New_Elmt_List;
9602 elsif Nkind (Constr) = N_Range
9603 or else (Nkind (Constr) = N_Attribute_Reference
9604 and then Attribute_Name (Constr) = Name_Range)
9607 ("a range is not a valid discriminant constraint", Constr);
9608 Discr_Expr (D) := Error;
9611 Process_Discriminant_Expression (Constr, Discr);
9612 Discr_Expr (D) := Constr;
9615 Next_Discriminant (Discr);
9619 if No (Discr) and then Present (Constr) then
9620 Error_Msg_N ("too many discriminants given in constraint", Constr);
9621 return New_Elmt_List;
9624 -- Named associations can be given in any order, but if both positional
9625 -- and named associations are used in the same discriminant constraint,
9626 -- then positional associations must occur first, at their normal
9627 -- position. Hence once a named association is used, the rest of the
9628 -- discriminant constraint must use only named associations.
9630 while Present (Constr) loop
9632 -- Positional association forbidden after a named association
9634 if Nkind (Constr) /= N_Discriminant_Association then
9635 Error_Msg_N ("positional association follows named one", Constr);
9636 return New_Elmt_List;
9638 -- Otherwise it is a named association
9641 -- E records the type of the discriminants in the named
9642 -- association. All the discriminants specified in the same name
9643 -- association must have the same type.
9647 -- Search the list of discriminants in T to see if the simple name
9648 -- given in the constraint matches any of them.
9650 Id := First (Selector_Names (Constr));
9651 while Present (Id) loop
9654 -- If Original_Discriminant is present, we are processing a
9655 -- generic instantiation and this is an instance node. We need
9656 -- to find the name of the corresponding discriminant in the
9657 -- actual record type T and not the name of the discriminant in
9658 -- the generic formal. Example:
9661 -- type G (D : int) is private;
9663 -- subtype W is G (D => 1);
9665 -- type Rec (X : int) is record ... end record;
9666 -- package Q is new P (G => Rec);
9668 -- At the point of the instantiation, formal type G is Rec
9669 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9670 -- which really looks like "subtype W is Rec (D => 1);" at
9671 -- the point of instantiation, we want to find the discriminant
9672 -- that corresponds to D in Rec, i.e. X.
9674 if Present (Original_Discriminant (Id))
9675 and then In_Instance
9677 Discr := Find_Corresponding_Discriminant (Id, T);
9681 Discr := First_Discriminant (T);
9682 while Present (Discr) loop
9683 if Chars (Discr) = Chars (Id) then
9688 Next_Discriminant (Discr);
9692 Error_Msg_N ("& does not match any discriminant", Id);
9693 return New_Elmt_List;
9695 -- If the parent type is a generic formal, preserve the
9696 -- name of the discriminant for subsequent instances.
9697 -- see comment at the beginning of this if statement.
9699 elsif Is_Generic_Type (Root_Type (T)) then
9700 Set_Original_Discriminant (Id, Discr);
9704 Position := Pos_Of_Discr (T, Discr);
9706 if Present (Discr_Expr (Position)) then
9707 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9710 -- Each discriminant specified in the same named association
9711 -- must be associated with a separate copy of the
9712 -- corresponding expression.
9714 if Present (Next (Id)) then
9715 Expr := New_Copy_Tree (Expression (Constr));
9716 Set_Parent (Expr, Parent (Expression (Constr)));
9718 Expr := Expression (Constr);
9721 Discr_Expr (Position) := Expr;
9722 Process_Discriminant_Expression (Expr, Discr);
9725 -- A discriminant association with more than one discriminant
9726 -- name is only allowed if the named discriminants are all of
9727 -- the same type (RM 3.7.1(8)).
9730 E := Base_Type (Etype (Discr));
9732 elsif Base_Type (Etype (Discr)) /= E then
9734 ("all discriminants in an association " &
9735 "must have the same type", Id);
9745 -- A discriminant constraint must provide exactly one value for each
9746 -- discriminant of the type (RM 3.7.1(8)).
9748 for J in Discr_Expr'Range loop
9749 if No (Discr_Expr (J)) then
9750 Error_Msg_N ("too few discriminants given in constraint", C);
9751 return New_Elmt_List;
9755 -- Determine if there are discriminant expressions in the constraint
9757 for J in Discr_Expr'Range loop
9758 if Denotes_Discriminant
9759 (Discr_Expr (J), Check_Concurrent => True)
9761 Discrim_Present := True;
9765 -- Build an element list consisting of the expressions given in the
9766 -- discriminant constraint and apply the appropriate checks. The list
9767 -- is constructed after resolving any named discriminant associations
9768 -- and therefore the expressions appear in the textual order of the
9771 Discr := First_Discriminant (T);
9772 for J in Discr_Expr'Range loop
9773 if Discr_Expr (J) /= Error then
9774 Append_Elmt (Discr_Expr (J), Elist);
9776 -- If any of the discriminant constraints is given by a
9777 -- discriminant and we are in a derived type declaration we
9778 -- have a discriminant renaming. Establish link between new
9779 -- and old discriminant. The new discriminant has an implicit
9780 -- dereference if the old one does.
9782 if Denotes_Discriminant (Discr_Expr (J)) then
9785 New_Discr : constant Entity_Id := Entity (Discr_Expr (J));
9788 Set_Corresponding_Discriminant (New_Discr, Discr);
9789 Set_Has_Implicit_Dereference (New_Discr,
9790 Has_Implicit_Dereference (Discr));
9794 -- Force the evaluation of non-discriminant expressions.
9795 -- If we have found a discriminant in the constraint 3.4(26)
9796 -- and 3.8(18) demand that no range checks are performed are
9797 -- after evaluation. If the constraint is for a component
9798 -- definition that has a per-object constraint, expressions are
9799 -- evaluated but not checked either. In all other cases perform
9803 if Discrim_Present then
9806 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9807 and then Has_Per_Object_Constraint
9808 (Defining_Identifier (Parent (Parent (Def))))
9812 elsif Is_Access_Type (Etype (Discr)) then
9813 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9816 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9819 Force_Evaluation (Discr_Expr (J));
9822 -- Check that the designated type of an access discriminant's
9823 -- expression is not a class-wide type unless the discriminant's
9824 -- designated type is also class-wide.
9826 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9827 and then not Is_Class_Wide_Type
9828 (Designated_Type (Etype (Discr)))
9829 and then Etype (Discr_Expr (J)) /= Any_Type
9830 and then Is_Class_Wide_Type
9831 (Designated_Type (Etype (Discr_Expr (J))))
9833 Wrong_Type (Discr_Expr (J), Etype (Discr));
9835 elsif Is_Access_Type (Etype (Discr))
9836 and then not Is_Access_Constant (Etype (Discr))
9837 and then Is_Access_Type (Etype (Discr_Expr (J)))
9838 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9841 ("constraint for discriminant& must be access to variable",
9846 Next_Discriminant (Discr);
9850 end Build_Discriminant_Constraints;
9852 ---------------------------------
9853 -- Build_Discriminated_Subtype --
9854 ---------------------------------
9856 procedure Build_Discriminated_Subtype
9860 Related_Nod : Node_Id;
9861 For_Access : Boolean := False)
9863 Has_Discrs : constant Boolean := Has_Discriminants (T);
9864 Constrained : constant Boolean :=
9866 and then not Is_Empty_Elmt_List (Elist)
9867 and then not Is_Class_Wide_Type (T))
9868 or else Is_Constrained (T);
9871 if Ekind (T) = E_Record_Type then
9873 Set_Ekind (Def_Id, E_Private_Subtype);
9874 Set_Is_For_Access_Subtype (Def_Id, True);
9876 Set_Ekind (Def_Id, E_Record_Subtype);
9879 -- Inherit preelaboration flag from base, for types for which it
9880 -- may have been set: records, private types, protected types.
9882 Set_Known_To_Have_Preelab_Init
9883 (Def_Id, Known_To_Have_Preelab_Init (T));
9885 elsif Ekind (T) = E_Task_Type then
9886 Set_Ekind (Def_Id, E_Task_Subtype);
9888 elsif Ekind (T) = E_Protected_Type then
9889 Set_Ekind (Def_Id, E_Protected_Subtype);
9890 Set_Known_To_Have_Preelab_Init
9891 (Def_Id, Known_To_Have_Preelab_Init (T));
9893 elsif Is_Private_Type (T) then
9894 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9895 Set_Known_To_Have_Preelab_Init
9896 (Def_Id, Known_To_Have_Preelab_Init (T));
9898 -- Private subtypes may have private dependents
9900 Set_Private_Dependents (Def_Id, New_Elmt_List);
9902 elsif Is_Class_Wide_Type (T) then
9903 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9906 -- Incomplete type. Attach subtype to list of dependents, to be
9907 -- completed with full view of parent type, unless is it the
9908 -- designated subtype of a record component within an init_proc.
9909 -- This last case arises for a component of an access type whose
9910 -- designated type is incomplete (e.g. a Taft Amendment type).
9911 -- The designated subtype is within an inner scope, and needs no
9912 -- elaboration, because only the access type is needed in the
9913 -- initialization procedure.
9915 Set_Ekind (Def_Id, Ekind (T));
9917 if For_Access and then Within_Init_Proc then
9920 Append_Elmt (Def_Id, Private_Dependents (T));
9924 Set_Etype (Def_Id, T);
9925 Init_Size_Align (Def_Id);
9926 Set_Has_Discriminants (Def_Id, Has_Discrs);
9927 Set_Is_Constrained (Def_Id, Constrained);
9929 Set_First_Entity (Def_Id, First_Entity (T));
9930 Set_Last_Entity (Def_Id, Last_Entity (T));
9931 Set_Has_Implicit_Dereference
9932 (Def_Id, Has_Implicit_Dereference (T));
9933 Set_Has_Pragma_Unreferenced_Objects
9934 (Def_Id, Has_Pragma_Unreferenced_Objects (T));
9936 -- If the subtype is the completion of a private declaration, there may
9937 -- have been representation clauses for the partial view, and they must
9938 -- be preserved. Build_Derived_Type chains the inherited clauses with
9939 -- the ones appearing on the extension. If this comes from a subtype
9940 -- declaration, all clauses are inherited.
9942 if No (First_Rep_Item (Def_Id)) then
9943 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9946 if Is_Tagged_Type (T) then
9947 Set_Is_Tagged_Type (Def_Id);
9948 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9949 Make_Class_Wide_Type (Def_Id);
9952 Set_Stored_Constraint (Def_Id, No_Elist);
9955 Set_Discriminant_Constraint (Def_Id, Elist);
9956 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9959 if Is_Tagged_Type (T) then
9961 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9962 -- concurrent record type (which has the list of primitive
9965 if Ada_Version >= Ada_2005
9966 and then Is_Concurrent_Type (T)
9968 Set_Corresponding_Record_Type (Def_Id,
9969 Corresponding_Record_Type (T));
9971 Set_Direct_Primitive_Operations (Def_Id,
9972 Direct_Primitive_Operations (T));
9975 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9978 -- Subtypes introduced by component declarations do not need to be
9979 -- marked as delayed, and do not get freeze nodes, because the semantics
9980 -- verifies that the parents of the subtypes are frozen before the
9981 -- enclosing record is frozen.
9983 if not Is_Type (Scope (Def_Id)) then
9984 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9986 if Is_Private_Type (T)
9987 and then Present (Full_View (T))
9989 Conditional_Delay (Def_Id, Full_View (T));
9991 Conditional_Delay (Def_Id, T);
9995 if Is_Record_Type (T) then
9996 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9999 and then not Is_Empty_Elmt_List (Elist)
10000 and then not For_Access
10002 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
10003 elsif not For_Access then
10004 Set_Cloned_Subtype (Def_Id, T);
10007 end Build_Discriminated_Subtype;
10009 ---------------------------
10010 -- Build_Itype_Reference --
10011 ---------------------------
10013 procedure Build_Itype_Reference
10017 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
10020 -- Itype references are only created for use by the back-end
10022 if Inside_A_Generic then
10025 Set_Itype (IR, Ityp);
10026 Insert_After (Nod, IR);
10028 end Build_Itype_Reference;
10030 ------------------------
10031 -- Build_Scalar_Bound --
10032 ------------------------
10034 function Build_Scalar_Bound
10037 Der_T : Entity_Id) return Node_Id
10039 New_Bound : Entity_Id;
10042 -- Note: not clear why this is needed, how can the original bound
10043 -- be unanalyzed at this point? and if it is, what business do we
10044 -- have messing around with it? and why is the base type of the
10045 -- parent type the right type for the resolution. It probably is
10046 -- not. It is OK for the new bound we are creating, but not for
10047 -- the old one??? Still if it never happens, no problem.
10049 Analyze_And_Resolve (Bound, Base_Type (Par_T));
10051 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
10052 New_Bound := New_Copy (Bound);
10053 Set_Etype (New_Bound, Der_T);
10054 Set_Analyzed (New_Bound);
10056 elsif Is_Entity_Name (Bound) then
10057 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
10059 -- The following is almost certainly wrong. What business do we have
10060 -- relocating a node (Bound) that is presumably still attached to
10061 -- the tree elsewhere???
10064 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
10067 Set_Etype (New_Bound, Der_T);
10069 end Build_Scalar_Bound;
10071 --------------------------------
10072 -- Build_Underlying_Full_View --
10073 --------------------------------
10075 procedure Build_Underlying_Full_View
10080 Loc : constant Source_Ptr := Sloc (N);
10081 Subt : constant Entity_Id :=
10082 Make_Defining_Identifier
10083 (Loc, New_External_Name (Chars (Typ), 'S'));
10090 procedure Set_Discriminant_Name (Id : Node_Id);
10091 -- If the derived type has discriminants, they may rename discriminants
10092 -- of the parent. When building the full view of the parent, we need to
10093 -- recover the names of the original discriminants if the constraint is
10094 -- given by named associations.
10096 ---------------------------
10097 -- Set_Discriminant_Name --
10098 ---------------------------
10100 procedure Set_Discriminant_Name (Id : Node_Id) is
10104 Set_Original_Discriminant (Id, Empty);
10106 if Has_Discriminants (Typ) then
10107 Disc := First_Discriminant (Typ);
10108 while Present (Disc) loop
10109 if Chars (Disc) = Chars (Id)
10110 and then Present (Corresponding_Discriminant (Disc))
10112 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
10114 Next_Discriminant (Disc);
10117 end Set_Discriminant_Name;
10119 -- Start of processing for Build_Underlying_Full_View
10122 if Nkind (N) = N_Full_Type_Declaration then
10123 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
10125 elsif Nkind (N) = N_Subtype_Declaration then
10126 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
10128 elsif Nkind (N) = N_Component_Declaration then
10131 (Constraint (Subtype_Indication (Component_Definition (N))));
10134 raise Program_Error;
10137 C := First (Constraints (Constr));
10138 while Present (C) loop
10139 if Nkind (C) = N_Discriminant_Association then
10140 Id := First (Selector_Names (C));
10141 while Present (Id) loop
10142 Set_Discriminant_Name (Id);
10151 Make_Subtype_Declaration (Loc,
10152 Defining_Identifier => Subt,
10153 Subtype_Indication =>
10154 Make_Subtype_Indication (Loc,
10155 Subtype_Mark => New_Occurrence_Of (Par, Loc),
10156 Constraint => New_Copy_Tree (Constr)));
10158 -- If this is a component subtype for an outer itype, it is not
10159 -- a list member, so simply set the parent link for analysis: if
10160 -- the enclosing type does not need to be in a declarative list,
10161 -- neither do the components.
10163 if Is_List_Member (N)
10164 and then Nkind (N) /= N_Component_Declaration
10166 Insert_Before (N, Indic);
10168 Set_Parent (Indic, Parent (N));
10172 Set_Underlying_Full_View (Typ, Full_View (Subt));
10173 Set_Is_Underlying_Full_View (Full_View (Subt));
10174 end Build_Underlying_Full_View;
10176 -------------------------------
10177 -- Check_Abstract_Overriding --
10178 -------------------------------
10180 procedure Check_Abstract_Overriding (T : Entity_Id) is
10181 Alias_Subp : Entity_Id;
10183 Op_List : Elist_Id;
10185 Type_Def : Node_Id;
10187 procedure Check_Pragma_Implemented (Subp : Entity_Id);
10188 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
10189 -- which has pragma Implemented already set. Check whether Subp's entity
10190 -- kind conforms to the implementation kind of the overridden routine.
10192 procedure Check_Pragma_Implemented
10194 Iface_Subp : Entity_Id);
10195 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
10196 -- Iface_Subp and both entities have pragma Implemented already set on
10197 -- them. Check whether the two implementation kinds are conforming.
10199 procedure Inherit_Pragma_Implemented
10201 Iface_Subp : Entity_Id);
10202 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
10203 -- subprogram Iface_Subp which has been marked by pragma Implemented.
10204 -- Propagate the implementation kind of Iface_Subp to Subp.
10206 ------------------------------
10207 -- Check_Pragma_Implemented --
10208 ------------------------------
10210 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
10211 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
10212 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
10213 Subp_Alias : constant Entity_Id := Alias (Subp);
10214 Contr_Typ : Entity_Id;
10215 Impl_Subp : Entity_Id;
10218 -- Subp must have an alias since it is a hidden entity used to link
10219 -- an interface subprogram to its overriding counterpart.
10221 pragma Assert (Present (Subp_Alias));
10223 -- Handle aliases to synchronized wrappers
10225 Impl_Subp := Subp_Alias;
10227 if Is_Primitive_Wrapper (Impl_Subp) then
10228 Impl_Subp := Wrapped_Entity (Impl_Subp);
10231 -- Extract the type of the controlling formal
10233 Contr_Typ := Etype (First_Formal (Subp_Alias));
10235 if Is_Concurrent_Record_Type (Contr_Typ) then
10236 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
10239 -- An interface subprogram whose implementation kind is By_Entry must
10240 -- be implemented by an entry.
10242 if Impl_Kind = Name_By_Entry
10243 and then Ekind (Impl_Subp) /= E_Entry
10245 Error_Msg_Node_2 := Iface_Alias;
10247 ("type & must implement abstract subprogram & with an entry",
10248 Subp_Alias, Contr_Typ);
10250 elsif Impl_Kind = Name_By_Protected_Procedure then
10252 -- An interface subprogram whose implementation kind is By_
10253 -- Protected_Procedure cannot be implemented by a primitive
10254 -- procedure of a task type.
10256 if Ekind (Contr_Typ) /= E_Protected_Type then
10257 Error_Msg_Node_2 := Contr_Typ;
10259 ("interface subprogram & cannot be implemented by a " &
10260 "primitive procedure of task type &", Subp_Alias,
10263 -- An interface subprogram whose implementation kind is By_
10264 -- Protected_Procedure must be implemented by a procedure.
10266 elsif Ekind (Impl_Subp) /= E_Procedure then
10267 Error_Msg_Node_2 := Iface_Alias;
10269 ("type & must implement abstract subprogram & with a " &
10270 "procedure", Subp_Alias, Contr_Typ);
10272 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10273 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10275 Error_Msg_Name_1 := Impl_Kind;
10277 ("overriding operation& must have synchronization%",
10281 -- If primitive has Optional synchronization, overriding operation
10282 -- must match if it has an explicit synchronization..
10284 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10285 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10287 Error_Msg_Name_1 := Impl_Kind;
10289 ("overriding operation& must have syncrhonization%",
10292 end Check_Pragma_Implemented;
10294 ------------------------------
10295 -- Check_Pragma_Implemented --
10296 ------------------------------
10298 procedure Check_Pragma_Implemented
10300 Iface_Subp : Entity_Id)
10302 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10303 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10306 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10307 -- and overriding subprogram are different. In general this is an
10308 -- error except when the implementation kind of the overridden
10309 -- subprograms is By_Any or Optional.
10311 if Iface_Kind /= Subp_Kind
10312 and then Iface_Kind /= Name_By_Any
10313 and then Iface_Kind /= Name_Optional
10315 if Iface_Kind = Name_By_Entry then
10317 ("incompatible implementation kind, overridden subprogram " &
10318 "is marked By_Entry", Subp);
10321 ("incompatible implementation kind, overridden subprogram " &
10322 "is marked By_Protected_Procedure", Subp);
10325 end Check_Pragma_Implemented;
10327 --------------------------------
10328 -- Inherit_Pragma_Implemented --
10329 --------------------------------
10331 procedure Inherit_Pragma_Implemented
10333 Iface_Subp : Entity_Id)
10335 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10336 Loc : constant Source_Ptr := Sloc (Subp);
10337 Impl_Prag : Node_Id;
10340 -- Since the implementation kind is stored as a representation item
10341 -- rather than a flag, create a pragma node.
10345 Chars => Name_Implemented,
10346 Pragma_Argument_Associations => New_List (
10347 Make_Pragma_Argument_Association (Loc,
10348 Expression => New_Occurrence_Of (Subp, Loc)),
10350 Make_Pragma_Argument_Association (Loc,
10351 Expression => Make_Identifier (Loc, Iface_Kind))));
10353 -- The pragma doesn't need to be analyzed because it is internally
10354 -- built. It is safe to directly register it as a rep item since we
10355 -- are only interested in the characters of the implementation kind.
10357 Record_Rep_Item (Subp, Impl_Prag);
10358 end Inherit_Pragma_Implemented;
10360 -- Start of processing for Check_Abstract_Overriding
10363 Op_List := Primitive_Operations (T);
10365 -- Loop to check primitive operations
10367 Elmt := First_Elmt (Op_List);
10368 while Present (Elmt) loop
10369 Subp := Node (Elmt);
10370 Alias_Subp := Alias (Subp);
10372 -- Inherited subprograms are identified by the fact that they do not
10373 -- come from source, and the associated source location is the
10374 -- location of the first subtype of the derived type.
10376 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10377 -- subprograms that "require overriding".
10379 -- Special exception, do not complain about failure to override the
10380 -- stream routines _Input and _Output, as well as the primitive
10381 -- operations used in dispatching selects since we always provide
10382 -- automatic overridings for these subprograms.
10384 -- The partial view of T may have been a private extension, for
10385 -- which inherited functions dispatching on result are abstract.
10386 -- If the full view is a null extension, there is no need for
10387 -- overriding in Ada 2005, but wrappers need to be built for them
10388 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10390 if Is_Null_Extension (T)
10391 and then Has_Controlling_Result (Subp)
10392 and then Ada_Version >= Ada_2005
10393 and then Present (Alias_Subp)
10394 and then not Comes_From_Source (Subp)
10395 and then not Is_Abstract_Subprogram (Alias_Subp)
10396 and then not Is_Access_Type (Etype (Subp))
10400 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10401 -- processing because this check is done with the aliased
10404 elsif Present (Interface_Alias (Subp)) then
10407 elsif (Is_Abstract_Subprogram (Subp)
10408 or else Requires_Overriding (Subp)
10410 (Has_Controlling_Result (Subp)
10411 and then Present (Alias_Subp)
10412 and then not Comes_From_Source (Subp)
10413 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10414 and then not Is_TSS (Subp, TSS_Stream_Input)
10415 and then not Is_TSS (Subp, TSS_Stream_Output)
10416 and then not Is_Abstract_Type (T)
10417 and then not Is_Predefined_Interface_Primitive (Subp)
10419 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10420 -- with abstract interface types because the check will be done
10421 -- with the aliased entity (otherwise we generate a duplicated
10424 and then not Present (Interface_Alias (Subp))
10426 if Present (Alias_Subp) then
10428 -- Only perform the check for a derived subprogram when the
10429 -- type has an explicit record extension. This avoids incorrect
10430 -- flagging of abstract subprograms for the case of a type
10431 -- without an extension that is derived from a formal type
10432 -- with a tagged actual (can occur within a private part).
10434 -- Ada 2005 (AI-391): In the case of an inherited function with
10435 -- a controlling result of the type, the rule does not apply if
10436 -- the type is a null extension (unless the parent function
10437 -- itself is abstract, in which case the function must still be
10438 -- be overridden). The expander will generate an overriding
10439 -- wrapper function calling the parent subprogram (see
10440 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10442 Type_Def := Type_Definition (Parent (T));
10444 if Nkind (Type_Def) = N_Derived_Type_Definition
10445 and then Present (Record_Extension_Part (Type_Def))
10447 (Ada_Version < Ada_2005
10448 or else not Is_Null_Extension (T)
10449 or else Ekind (Subp) = E_Procedure
10450 or else not Has_Controlling_Result (Subp)
10451 or else Is_Abstract_Subprogram (Alias_Subp)
10452 or else Requires_Overriding (Subp)
10453 or else Is_Access_Type (Etype (Subp)))
10455 -- Avoid reporting error in case of abstract predefined
10456 -- primitive inherited from interface type because the
10457 -- body of internally generated predefined primitives
10458 -- of tagged types are generated later by Freeze_Type
10460 if Is_Interface (Root_Type (T))
10461 and then Is_Abstract_Subprogram (Subp)
10462 and then Is_Predefined_Dispatching_Operation (Subp)
10463 and then not Comes_From_Source (Ultimate_Alias (Subp))
10467 -- A null extension is not obliged to override an inherited
10468 -- procedure subject to pragma Extensions_Visible with value
10469 -- False and at least one controlling OUT parameter
10470 -- (SPARK RM 6.1.7(6)).
10472 elsif Is_Null_Extension (T)
10473 and then Is_EVF_Procedure (Subp)
10479 ("type must be declared abstract or & overridden",
10482 -- Traverse the whole chain of aliased subprograms to
10483 -- complete the error notification. This is especially
10484 -- useful for traceability of the chain of entities when
10485 -- the subprogram corresponds with an interface
10486 -- subprogram (which may be defined in another package).
10488 if Present (Alias_Subp) then
10494 while Present (Alias (E)) loop
10496 -- Avoid reporting redundant errors on entities
10497 -- inherited from interfaces
10499 if Sloc (E) /= Sloc (T) then
10500 Error_Msg_Sloc := Sloc (E);
10502 ("\& has been inherited #", T, Subp);
10508 Error_Msg_Sloc := Sloc (E);
10510 -- AI05-0068: report if there is an overriding
10511 -- non-abstract subprogram that is invisible.
10514 and then not Is_Abstract_Subprogram (E)
10517 ("\& subprogram# is not visible",
10520 -- Clarify the case where a non-null extension must
10521 -- override inherited procedure subject to pragma
10522 -- Extensions_Visible with value False and at least
10523 -- one controlling OUT param.
10525 elsif Is_EVF_Procedure (E) then
10527 ("\& # is subject to Extensions_Visible False",
10532 ("\& has been inherited from subprogram #",
10539 -- Ada 2005 (AI-345): Protected or task type implementing
10540 -- abstract interfaces.
10542 elsif Is_Concurrent_Record_Type (T)
10543 and then Present (Interfaces (T))
10545 -- There is no need to check here RM 9.4(11.9/3) since we
10546 -- are processing the corresponding record type and the
10547 -- mode of the overriding subprograms was verified by
10548 -- Check_Conformance when the corresponding concurrent
10549 -- type declaration was analyzed.
10552 ("interface subprogram & must be overridden", T, Subp);
10554 -- Examine primitive operations of synchronized type to find
10555 -- homonyms that have the wrong profile.
10561 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10562 while Present (Prim) loop
10563 if Chars (Prim) = Chars (Subp) then
10565 ("profile is not type conformant with prefixed "
10566 & "view profile of inherited operation&",
10570 Next_Entity (Prim);
10576 Error_Msg_Node_2 := T;
10578 ("abstract subprogram& not allowed for type&", Subp);
10580 -- Also post unconditional warning on the type (unconditional
10581 -- so that if there are more than one of these cases, we get
10582 -- them all, and not just the first one).
10584 Error_Msg_Node_2 := Subp;
10585 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10588 -- A subprogram subject to pragma Extensions_Visible with value
10589 -- "True" cannot override a subprogram subject to the same pragma
10590 -- with value "False" (SPARK RM 6.1.7(5)).
10592 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10593 and then Present (Overridden_Operation (Subp))
10594 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10595 Extensions_Visible_False
10597 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10599 ("subprogram & with Extensions_Visible True cannot override "
10600 & "subprogram # with Extensions_Visible False", Subp);
10603 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10605 -- Subp is an expander-generated procedure which maps an interface
10606 -- alias to a protected wrapper. The interface alias is flagged by
10607 -- pragma Implemented. Ensure that Subp is a procedure when the
10608 -- implementation kind is By_Protected_Procedure or an entry when
10611 if Ada_Version >= Ada_2012
10612 and then Is_Hidden (Subp)
10613 and then Present (Interface_Alias (Subp))
10614 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10616 Check_Pragma_Implemented (Subp);
10619 -- Subp is an interface primitive which overrides another interface
10620 -- primitive marked with pragma Implemented.
10622 if Ada_Version >= Ada_2012
10623 and then Present (Overridden_Operation (Subp))
10624 and then Has_Rep_Pragma
10625 (Overridden_Operation (Subp), Name_Implemented)
10627 -- If the overriding routine is also marked by Implemented, check
10628 -- that the two implementation kinds are conforming.
10630 if Has_Rep_Pragma (Subp, Name_Implemented) then
10631 Check_Pragma_Implemented
10633 Iface_Subp => Overridden_Operation (Subp));
10635 -- Otherwise the overriding routine inherits the implementation
10636 -- kind from the overridden subprogram.
10639 Inherit_Pragma_Implemented
10641 Iface_Subp => Overridden_Operation (Subp));
10645 -- If the operation is a wrapper for a synchronized primitive, it
10646 -- may be called indirectly through a dispatching select. We assume
10647 -- that it will be referenced elsewhere indirectly, and suppress
10648 -- warnings about an unused entity.
10650 if Is_Primitive_Wrapper (Subp)
10651 and then Present (Wrapped_Entity (Subp))
10653 Set_Referenced (Wrapped_Entity (Subp));
10658 end Check_Abstract_Overriding;
10660 ------------------------------------------------
10661 -- Check_Access_Discriminant_Requires_Limited --
10662 ------------------------------------------------
10664 procedure Check_Access_Discriminant_Requires_Limited
10669 -- A discriminant_specification for an access discriminant shall appear
10670 -- only in the declaration for a task or protected type, or for a type
10671 -- with the reserved word 'limited' in its definition or in one of its
10672 -- ancestors (RM 3.7(10)).
10674 -- AI-0063: The proper condition is that type must be immutably limited,
10675 -- or else be a partial view.
10677 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10678 if Is_Limited_View (Current_Scope)
10680 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10681 and then Limited_Present (Parent (Current_Scope)))
10687 ("access discriminants allowed only for limited types", Loc);
10690 end Check_Access_Discriminant_Requires_Limited;
10692 -----------------------------------
10693 -- Check_Aliased_Component_Types --
10694 -----------------------------------
10696 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10700 -- ??? Also need to check components of record extensions, but not
10701 -- components of protected types (which are always limited).
10703 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10704 -- types to be unconstrained. This is safe because it is illegal to
10705 -- create access subtypes to such types with explicit discriminant
10708 if not Is_Limited_Type (T) then
10709 if Ekind (T) = E_Record_Type then
10710 C := First_Component (T);
10711 while Present (C) loop
10713 and then Has_Discriminants (Etype (C))
10714 and then not Is_Constrained (Etype (C))
10715 and then not In_Instance_Body
10716 and then Ada_Version < Ada_2005
10719 ("aliased component must be constrained (RM 3.6(11))",
10723 Next_Component (C);
10726 elsif Ekind (T) = E_Array_Type then
10727 if Has_Aliased_Components (T)
10728 and then Has_Discriminants (Component_Type (T))
10729 and then not Is_Constrained (Component_Type (T))
10730 and then not In_Instance_Body
10731 and then Ada_Version < Ada_2005
10734 ("aliased component type must be constrained (RM 3.6(11))",
10739 end Check_Aliased_Component_Types;
10741 ---------------------------------------
10742 -- Check_Anonymous_Access_Components --
10743 ---------------------------------------
10745 procedure Check_Anonymous_Access_Components
10746 (Typ_Decl : Node_Id;
10749 Comp_List : Node_Id)
10751 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10752 Anon_Access : Entity_Id;
10755 Comp_Def : Node_Id;
10757 Type_Def : Node_Id;
10759 procedure Build_Incomplete_Type_Declaration;
10760 -- If the record type contains components that include an access to the
10761 -- current record, then create an incomplete type declaration for the
10762 -- record, to be used as the designated type of the anonymous access.
10763 -- This is done only once, and only if there is no previous partial
10764 -- view of the type.
10766 function Designates_T (Subt : Node_Id) return Boolean;
10767 -- Check whether a node designates the enclosing record type, or 'Class
10770 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10771 -- Check whether an access definition includes a reference to
10772 -- the enclosing record type. The reference can be a subtype mark
10773 -- in the access definition itself, a 'Class attribute reference, or
10774 -- recursively a reference appearing in a parameter specification
10775 -- or result definition of an access_to_subprogram definition.
10777 --------------------------------------
10778 -- Build_Incomplete_Type_Declaration --
10779 --------------------------------------
10781 procedure Build_Incomplete_Type_Declaration is
10786 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10787 -- it's "is new ... with record" or else "is tagged record ...".
10789 Is_Tagged : constant Boolean :=
10790 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10792 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10794 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10795 and then Tagged_Present (Type_Definition (Typ_Decl)));
10798 -- If there is a previous partial view, no need to create a new one
10799 -- If the partial view, given by Prev, is incomplete, If Prev is
10800 -- a private declaration, full declaration is flagged accordingly.
10802 if Prev /= Typ then
10804 Make_Class_Wide_Type (Prev);
10805 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10806 Set_Etype (Class_Wide_Type (Typ), Typ);
10811 elsif Has_Private_Declaration (Typ) then
10813 -- If we refer to T'Class inside T, and T is the completion of a
10814 -- private type, then make sure the class-wide type exists.
10817 Make_Class_Wide_Type (Typ);
10822 -- If there was a previous anonymous access type, the incomplete
10823 -- type declaration will have been created already.
10825 elsif Present (Current_Entity (Typ))
10826 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10827 and then Full_View (Current_Entity (Typ)) = Typ
10830 and then Comes_From_Source (Current_Entity (Typ))
10831 and then not Is_Tagged_Type (Current_Entity (Typ))
10833 Make_Class_Wide_Type (Typ);
10835 ("incomplete view of tagged type should be declared tagged??",
10836 Parent (Current_Entity (Typ)));
10841 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10842 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10844 -- Type has already been inserted into the current scope. Remove
10845 -- it, and add incomplete declaration for type, so that subsequent
10846 -- anonymous access types can use it. The entity is unchained from
10847 -- the homonym list and from immediate visibility. After analysis,
10848 -- the entity in the incomplete declaration becomes immediately
10849 -- visible in the record declaration that follows.
10851 H := Current_Entity (Typ);
10854 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10857 and then Homonym (H) /= Typ
10859 H := Homonym (Typ);
10862 Set_Homonym (H, Homonym (Typ));
10865 Insert_Before (Typ_Decl, Decl);
10867 Set_Full_View (Inc_T, Typ);
10871 -- Create a common class-wide type for both views, and set the
10872 -- Etype of the class-wide type to the full view.
10874 Make_Class_Wide_Type (Inc_T);
10875 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10876 Set_Etype (Class_Wide_Type (Typ), Typ);
10879 end Build_Incomplete_Type_Declaration;
10885 function Designates_T (Subt : Node_Id) return Boolean is
10886 Type_Id : constant Name_Id := Chars (Typ);
10888 function Names_T (Nam : Node_Id) return Boolean;
10889 -- The record type has not been introduced in the current scope
10890 -- yet, so we must examine the name of the type itself, either
10891 -- an identifier T, or an expanded name of the form P.T, where
10892 -- P denotes the current scope.
10898 function Names_T (Nam : Node_Id) return Boolean is
10900 if Nkind (Nam) = N_Identifier then
10901 return Chars (Nam) = Type_Id;
10903 elsif Nkind (Nam) = N_Selected_Component then
10904 if Chars (Selector_Name (Nam)) = Type_Id then
10905 if Nkind (Prefix (Nam)) = N_Identifier then
10906 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10908 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10909 return Chars (Selector_Name (Prefix (Nam))) =
10910 Chars (Current_Scope);
10924 -- Start of processing for Designates_T
10927 if Nkind (Subt) = N_Identifier then
10928 return Chars (Subt) = Type_Id;
10930 -- Reference can be through an expanded name which has not been
10931 -- analyzed yet, and which designates enclosing scopes.
10933 elsif Nkind (Subt) = N_Selected_Component then
10934 if Names_T (Subt) then
10937 -- Otherwise it must denote an entity that is already visible.
10938 -- The access definition may name a subtype of the enclosing
10939 -- type, if there is a previous incomplete declaration for it.
10942 Find_Selected_Component (Subt);
10944 Is_Entity_Name (Subt)
10945 and then Scope (Entity (Subt)) = Current_Scope
10947 (Chars (Base_Type (Entity (Subt))) = Type_Id
10949 (Is_Class_Wide_Type (Entity (Subt))
10951 Chars (Etype (Base_Type (Entity (Subt)))) =
10955 -- A reference to the current type may appear as the prefix of
10956 -- a 'Class attribute.
10958 elsif Nkind (Subt) = N_Attribute_Reference
10959 and then Attribute_Name (Subt) = Name_Class
10961 return Names_T (Prefix (Subt));
10972 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10973 Param_Spec : Node_Id;
10975 Acc_Subprg : constant Node_Id :=
10976 Access_To_Subprogram_Definition (Acc_Def);
10979 if No (Acc_Subprg) then
10980 return Designates_T (Subtype_Mark (Acc_Def));
10983 -- Component is an access_to_subprogram: examine its formals,
10984 -- and result definition in the case of an access_to_function.
10986 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10987 while Present (Param_Spec) loop
10988 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10989 and then Mentions_T (Parameter_Type (Param_Spec))
10993 elsif Designates_T (Parameter_Type (Param_Spec)) then
11000 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
11001 if Nkind (Result_Definition (Acc_Subprg)) =
11002 N_Access_Definition
11004 return Mentions_T (Result_Definition (Acc_Subprg));
11006 return Designates_T (Result_Definition (Acc_Subprg));
11013 -- Start of processing for Check_Anonymous_Access_Components
11016 if No (Comp_List) then
11020 Comp := First (Component_Items (Comp_List));
11021 while Present (Comp) loop
11022 if Nkind (Comp) = N_Component_Declaration
11024 (Access_Definition (Component_Definition (Comp)))
11026 Mentions_T (Access_Definition (Component_Definition (Comp)))
11028 Comp_Def := Component_Definition (Comp);
11030 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
11032 Build_Incomplete_Type_Declaration;
11033 Anon_Access := Make_Temporary (Loc, 'S');
11035 -- Create a declaration for the anonymous access type: either
11036 -- an access_to_object or an access_to_subprogram.
11038 if Present (Acc_Def) then
11039 if Nkind (Acc_Def) = N_Access_Function_Definition then
11041 Make_Access_Function_Definition (Loc,
11042 Parameter_Specifications =>
11043 Parameter_Specifications (Acc_Def),
11044 Result_Definition => Result_Definition (Acc_Def));
11047 Make_Access_Procedure_Definition (Loc,
11048 Parameter_Specifications =>
11049 Parameter_Specifications (Acc_Def));
11054 Make_Access_To_Object_Definition (Loc,
11055 Subtype_Indication =>
11057 (Subtype_Mark (Access_Definition (Comp_Def))));
11059 Set_Constant_Present
11060 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
11062 (Type_Def, All_Present (Access_Definition (Comp_Def)));
11065 Set_Null_Exclusion_Present
11067 Null_Exclusion_Present (Access_Definition (Comp_Def)));
11070 Make_Full_Type_Declaration (Loc,
11071 Defining_Identifier => Anon_Access,
11072 Type_Definition => Type_Def);
11074 Insert_Before (Typ_Decl, Decl);
11077 -- If an access to subprogram, create the extra formals
11079 if Present (Acc_Def) then
11080 Create_Extra_Formals (Designated_Type (Anon_Access));
11082 -- If an access to object, preserve entity of designated type,
11083 -- for ASIS use, before rewriting the component definition.
11090 Desig := Entity (Subtype_Indication (Type_Def));
11092 -- If the access definition is to the current record,
11093 -- the visible entity at this point is an incomplete
11094 -- type. Retrieve the full view to simplify ASIS queries
11096 if Ekind (Desig) = E_Incomplete_Type then
11097 Desig := Full_View (Desig);
11101 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
11106 Make_Component_Definition (Loc,
11107 Subtype_Indication =>
11108 New_Occurrence_Of (Anon_Access, Loc)));
11110 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
11111 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
11113 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
11116 Set_Is_Local_Anonymous_Access (Anon_Access);
11122 if Present (Variant_Part (Comp_List)) then
11126 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
11127 while Present (V) loop
11128 Check_Anonymous_Access_Components
11129 (Typ_Decl, Typ, Prev, Component_List (V));
11130 Next_Non_Pragma (V);
11134 end Check_Anonymous_Access_Components;
11136 ----------------------
11137 -- Check_Completion --
11138 ----------------------
11140 procedure Check_Completion (Body_Id : Node_Id := Empty) is
11143 procedure Post_Error;
11144 -- Post error message for lack of completion for entity E
11150 procedure Post_Error is
11151 procedure Missing_Body;
11152 -- Output missing body message
11158 procedure Missing_Body is
11160 -- Spec is in same unit, so we can post on spec
11162 if In_Same_Source_Unit (Body_Id, E) then
11163 Error_Msg_N ("missing body for &", E);
11165 -- Spec is in a separate unit, so we have to post on the body
11168 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
11172 -- Start of processing for Post_Error
11175 if not Comes_From_Source (E) then
11176 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
11178 -- It may be an anonymous protected type created for a
11179 -- single variable. Post error on variable, if present.
11185 Var := First_Entity (Current_Scope);
11186 while Present (Var) loop
11187 exit when Etype (Var) = E
11188 and then Comes_From_Source (Var);
11193 if Present (Var) then
11200 -- If a generated entity has no completion, then either previous
11201 -- semantic errors have disabled the expansion phase, or else we had
11202 -- missing subunits, or else we are compiling without expansion,
11203 -- or else something is very wrong.
11205 if not Comes_From_Source (E) then
11207 (Serious_Errors_Detected > 0
11208 or else Configurable_Run_Time_Violations > 0
11209 or else Subunits_Missing
11210 or else not Expander_Active);
11213 -- Here for source entity
11216 -- Here if no body to post the error message, so we post the error
11217 -- on the declaration that has no completion. This is not really
11218 -- the right place to post it, think about this later ???
11220 if No (Body_Id) then
11221 if Is_Type (E) then
11223 ("missing full declaration for }", Parent (E), E);
11225 Error_Msg_NE ("missing body for &", Parent (E), E);
11228 -- Package body has no completion for a declaration that appears
11229 -- in the corresponding spec. Post error on the body, with a
11230 -- reference to the non-completed declaration.
11233 Error_Msg_Sloc := Sloc (E);
11235 if Is_Type (E) then
11236 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
11238 elsif Is_Overloadable (E)
11239 and then Current_Entity_In_Scope (E) /= E
11241 -- It may be that the completion is mistyped and appears as
11242 -- a distinct overloading of the entity.
11245 Candidate : constant Entity_Id :=
11246 Current_Entity_In_Scope (E);
11247 Decl : constant Node_Id :=
11248 Unit_Declaration_Node (Candidate);
11251 if Is_Overloadable (Candidate)
11252 and then Ekind (Candidate) = Ekind (E)
11253 and then Nkind (Decl) = N_Subprogram_Body
11254 and then Acts_As_Spec (Decl)
11256 Check_Type_Conformant (Candidate, E);
11272 Pack_Id : constant Entity_Id := Current_Scope;
11274 -- Start of processing for Check_Completion
11277 E := First_Entity (Pack_Id);
11278 while Present (E) loop
11279 if Is_Intrinsic_Subprogram (E) then
11282 -- The following situation requires special handling: a child unit
11283 -- that appears in the context clause of the body of its parent:
11285 -- procedure Parent.Child (...);
11287 -- with Parent.Child;
11288 -- package body Parent is
11290 -- Here Parent.Child appears as a local entity, but should not be
11291 -- flagged as requiring completion, because it is a compilation
11294 -- Ignore missing completion for a subprogram that does not come from
11295 -- source (including the _Call primitive operation of RAS types,
11296 -- which has to have the flag Comes_From_Source for other purposes):
11297 -- we assume that the expander will provide the missing completion.
11298 -- In case of previous errors, other expansion actions that provide
11299 -- bodies for null procedures with not be invoked, so inhibit message
11302 -- Note that E_Operator is not in the list that follows, because
11303 -- this kind is reserved for predefined operators, that are
11304 -- intrinsic and do not need completion.
11306 elsif Ekind_In (E, E_Function,
11308 E_Generic_Function,
11309 E_Generic_Procedure)
11311 if Has_Completion (E) then
11314 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11317 elsif Is_Subprogram (E)
11318 and then (not Comes_From_Source (E)
11319 or else Chars (E) = Name_uCall)
11324 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11328 elsif Nkind (Parent (E)) = N_Procedure_Specification
11329 and then Null_Present (Parent (E))
11330 and then Serious_Errors_Detected > 0
11338 elsif Is_Entry (E) then
11339 if not Has_Completion (E) and then
11340 (Ekind (Scope (E)) = E_Protected_Object
11341 or else Ekind (Scope (E)) = E_Protected_Type)
11346 elsif Is_Package_Or_Generic_Package (E) then
11347 if Unit_Requires_Body (E) then
11348 if not Has_Completion (E)
11349 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11355 elsif not Is_Child_Unit (E) then
11356 May_Need_Implicit_Body (E);
11359 -- A formal incomplete type (Ada 2012) does not require a completion;
11360 -- other incomplete type declarations do.
11362 elsif Ekind (E) = E_Incomplete_Type
11363 and then No (Underlying_Type (E))
11364 and then not Is_Generic_Type (E)
11368 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11369 and then not Has_Completion (E)
11373 -- A single task declared in the current scope is a constant, verify
11374 -- that the body of its anonymous type is in the same scope. If the
11375 -- task is defined elsewhere, this may be a renaming declaration for
11376 -- which no completion is needed.
11378 elsif Ekind (E) = E_Constant
11379 and then Ekind (Etype (E)) = E_Task_Type
11380 and then not Has_Completion (Etype (E))
11381 and then Scope (Etype (E)) = Current_Scope
11385 elsif Ekind (E) = E_Protected_Object
11386 and then not Has_Completion (Etype (E))
11390 elsif Ekind (E) = E_Record_Type then
11391 if Is_Tagged_Type (E) then
11392 Check_Abstract_Overriding (E);
11393 Check_Conventions (E);
11396 Check_Aliased_Component_Types (E);
11398 elsif Ekind (E) = E_Array_Type then
11399 Check_Aliased_Component_Types (E);
11405 end Check_Completion;
11407 ------------------------------------
11408 -- Check_CPP_Type_Has_No_Defaults --
11409 ------------------------------------
11411 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11412 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11417 -- Obtain the component list
11419 if Nkind (Tdef) = N_Record_Definition then
11420 Clist := Component_List (Tdef);
11421 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11422 Clist := Component_List (Record_Extension_Part (Tdef));
11425 -- Check all components to ensure no default expressions
11427 if Present (Clist) then
11428 Comp := First (Component_Items (Clist));
11429 while Present (Comp) loop
11430 if Present (Expression (Comp)) then
11432 ("component of imported 'C'P'P type cannot have "
11433 & "default expression", Expression (Comp));
11439 end Check_CPP_Type_Has_No_Defaults;
11441 ----------------------------
11442 -- Check_Delta_Expression --
11443 ----------------------------
11445 procedure Check_Delta_Expression (E : Node_Id) is
11447 if not (Is_Real_Type (Etype (E))) then
11448 Wrong_Type (E, Any_Real);
11450 elsif not Is_OK_Static_Expression (E) then
11451 Flag_Non_Static_Expr
11452 ("non-static expression used for delta value!", E);
11454 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11455 Error_Msg_N ("delta expression must be positive", E);
11461 -- If any of above errors occurred, then replace the incorrect
11462 -- expression by the real 0.1, which should prevent further errors.
11465 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11466 Analyze_And_Resolve (E, Standard_Float);
11467 end Check_Delta_Expression;
11469 -----------------------------
11470 -- Check_Digits_Expression --
11471 -----------------------------
11473 procedure Check_Digits_Expression (E : Node_Id) is
11475 if not (Is_Integer_Type (Etype (E))) then
11476 Wrong_Type (E, Any_Integer);
11478 elsif not Is_OK_Static_Expression (E) then
11479 Flag_Non_Static_Expr
11480 ("non-static expression used for digits value!", E);
11482 elsif Expr_Value (E) <= 0 then
11483 Error_Msg_N ("digits value must be greater than zero", E);
11489 -- If any of above errors occurred, then replace the incorrect
11490 -- expression by the integer 1, which should prevent further errors.
11492 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11493 Analyze_And_Resolve (E, Standard_Integer);
11495 end Check_Digits_Expression;
11497 --------------------------
11498 -- Check_Initialization --
11499 --------------------------
11501 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11503 -- Special processing for limited types
11505 if Is_Limited_Type (T)
11506 and then not In_Instance
11507 and then not In_Inlined_Body
11509 if not OK_For_Limited_Init (T, Exp) then
11511 -- In GNAT mode, this is just a warning, to allow it to be evilly
11512 -- turned off. Otherwise it is a real error.
11516 ("??cannot initialize entities of limited type!", Exp);
11518 elsif Ada_Version < Ada_2005 then
11520 -- The side effect removal machinery may generate illegal Ada
11521 -- code to avoid the usage of access types and 'reference in
11522 -- SPARK mode. Since this is legal code with respect to theorem
11523 -- proving, do not emit the error.
11526 and then Nkind (Exp) = N_Function_Call
11527 and then Nkind (Parent (Exp)) = N_Object_Declaration
11528 and then not Comes_From_Source
11529 (Defining_Identifier (Parent (Exp)))
11535 ("cannot initialize entities of limited type", Exp);
11536 Explain_Limited_Type (T, Exp);
11540 -- Specialize error message according to kind of illegal
11541 -- initial expression.
11543 if Nkind (Exp) = N_Type_Conversion
11544 and then Nkind (Expression (Exp)) = N_Function_Call
11547 ("illegal context for call"
11548 & " to function with limited result", Exp);
11552 ("initialization of limited object requires aggregate "
11553 & "or function call", Exp);
11559 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11560 -- set unless we can be sure that no range check is required.
11562 if (GNATprove_Mode or not Expander_Active)
11563 and then Is_Scalar_Type (T)
11564 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11566 Set_Do_Range_Check (Exp);
11568 end Check_Initialization;
11570 ----------------------
11571 -- Check_Interfaces --
11572 ----------------------
11574 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11575 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11578 Iface_Def : Node_Id;
11579 Iface_Typ : Entity_Id;
11580 Parent_Node : Node_Id;
11582 Is_Task : Boolean := False;
11583 -- Set True if parent type or any progenitor is a task interface
11585 Is_Protected : Boolean := False;
11586 -- Set True if parent type or any progenitor is a protected interface
11588 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11589 -- Check that a progenitor is compatible with declaration. If an error
11590 -- message is output, it is posted on Error_Node.
11596 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11597 Iface_Id : constant Entity_Id :=
11598 Defining_Identifier (Parent (Iface_Def));
11599 Type_Def : Node_Id;
11602 if Nkind (N) = N_Private_Extension_Declaration then
11605 Type_Def := Type_Definition (N);
11608 if Is_Task_Interface (Iface_Id) then
11611 elsif Is_Protected_Interface (Iface_Id) then
11612 Is_Protected := True;
11615 if Is_Synchronized_Interface (Iface_Id) then
11617 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11618 -- extension derived from a synchronized interface must explicitly
11619 -- be declared synchronized, because the full view will be a
11620 -- synchronized type.
11622 if Nkind (N) = N_Private_Extension_Declaration then
11623 if not Synchronized_Present (N) then
11625 ("private extension of& must be explicitly synchronized",
11629 -- However, by 3.9.4(16/2), a full type that is a record extension
11630 -- is never allowed to derive from a synchronized interface (note
11631 -- that interfaces must be excluded from this check, because those
11632 -- are represented by derived type definitions in some cases).
11634 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11635 and then not Interface_Present (Type_Definition (N))
11637 Error_Msg_N ("record extension cannot derive from synchronized "
11638 & "interface", Error_Node);
11642 -- Check that the characteristics of the progenitor are compatible
11643 -- with the explicit qualifier in the declaration.
11644 -- The check only applies to qualifiers that come from source.
11645 -- Limited_Present also appears in the declaration of corresponding
11646 -- records, and the check does not apply to them.
11648 if Limited_Present (Type_Def)
11650 Is_Concurrent_Record_Type (Defining_Identifier (N))
11652 if Is_Limited_Interface (Parent_Type)
11653 and then not Is_Limited_Interface (Iface_Id)
11656 ("progenitor & must be limited interface",
11657 Error_Node, Iface_Id);
11660 (Task_Present (Iface_Def)
11661 or else Protected_Present (Iface_Def)
11662 or else Synchronized_Present (Iface_Def))
11663 and then Nkind (N) /= N_Private_Extension_Declaration
11664 and then not Error_Posted (N)
11667 ("progenitor & must be limited interface",
11668 Error_Node, Iface_Id);
11671 -- Protected interfaces can only inherit from limited, synchronized
11672 -- or protected interfaces.
11674 elsif Nkind (N) = N_Full_Type_Declaration
11675 and then Protected_Present (Type_Def)
11677 if Limited_Present (Iface_Def)
11678 or else Synchronized_Present (Iface_Def)
11679 or else Protected_Present (Iface_Def)
11683 elsif Task_Present (Iface_Def) then
11684 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11685 & "from task interface", Error_Node);
11688 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11689 & "from non-limited interface", Error_Node);
11692 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11693 -- limited and synchronized.
11695 elsif Synchronized_Present (Type_Def) then
11696 if Limited_Present (Iface_Def)
11697 or else Synchronized_Present (Iface_Def)
11701 elsif Protected_Present (Iface_Def)
11702 and then Nkind (N) /= N_Private_Extension_Declaration
11704 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11705 & "from protected interface", Error_Node);
11707 elsif Task_Present (Iface_Def)
11708 and then Nkind (N) /= N_Private_Extension_Declaration
11710 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11711 & "from task interface", Error_Node);
11713 elsif not Is_Limited_Interface (Iface_Id) then
11714 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11715 & "from non-limited interface", Error_Node);
11718 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11719 -- synchronized or task interfaces.
11721 elsif Nkind (N) = N_Full_Type_Declaration
11722 and then Task_Present (Type_Def)
11724 if Limited_Present (Iface_Def)
11725 or else Synchronized_Present (Iface_Def)
11726 or else Task_Present (Iface_Def)
11730 elsif Protected_Present (Iface_Def) then
11731 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11732 & "protected interface", Error_Node);
11735 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11736 & "non-limited interface", Error_Node);
11741 -- Start of processing for Check_Interfaces
11744 if Is_Interface (Parent_Type) then
11745 if Is_Task_Interface (Parent_Type) then
11748 elsif Is_Protected_Interface (Parent_Type) then
11749 Is_Protected := True;
11753 if Nkind (N) = N_Private_Extension_Declaration then
11755 -- Check that progenitors are compatible with declaration
11757 Iface := First (Interface_List (Def));
11758 while Present (Iface) loop
11759 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11761 Parent_Node := Parent (Base_Type (Iface_Typ));
11762 Iface_Def := Type_Definition (Parent_Node);
11764 if not Is_Interface (Iface_Typ) then
11765 Diagnose_Interface (Iface, Iface_Typ);
11767 Check_Ifaces (Iface_Def, Iface);
11773 if Is_Task and Is_Protected then
11775 ("type cannot derive from task and protected interface", N);
11781 -- Full type declaration of derived type.
11782 -- Check compatibility with parent if it is interface type
11784 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11785 and then Is_Interface (Parent_Type)
11787 Parent_Node := Parent (Parent_Type);
11789 -- More detailed checks for interface varieties
11792 (Iface_Def => Type_Definition (Parent_Node),
11793 Error_Node => Subtype_Indication (Type_Definition (N)));
11796 Iface := First (Interface_List (Def));
11797 while Present (Iface) loop
11798 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11800 Parent_Node := Parent (Base_Type (Iface_Typ));
11801 Iface_Def := Type_Definition (Parent_Node);
11803 if not Is_Interface (Iface_Typ) then
11804 Diagnose_Interface (Iface, Iface_Typ);
11807 -- "The declaration of a specific descendant of an interface
11808 -- type freezes the interface type" RM 13.14
11810 Freeze_Before (N, Iface_Typ);
11811 Check_Ifaces (Iface_Def, Error_Node => Iface);
11817 if Is_Task and Is_Protected then
11819 ("type cannot derive from task and protected interface", N);
11821 end Check_Interfaces;
11823 ------------------------------------
11824 -- Check_Or_Process_Discriminants --
11825 ------------------------------------
11827 -- If an incomplete or private type declaration was already given for the
11828 -- type, the discriminants may have already been processed if they were
11829 -- present on the incomplete declaration. In this case a full conformance
11830 -- check has been performed in Find_Type_Name, and we then recheck here
11831 -- some properties that can't be checked on the partial view alone.
11832 -- Otherwise we call Process_Discriminants.
11834 procedure Check_Or_Process_Discriminants
11837 Prev : Entity_Id := Empty)
11840 if Has_Discriminants (T) then
11842 -- Discriminants are already set on T if they were already present
11843 -- on the partial view. Make them visible to component declarations.
11847 -- Discriminant on T (full view) referencing expr on partial view
11849 Prev_D : Entity_Id;
11850 -- Entity of corresponding discriminant on partial view
11853 -- Discriminant specification for full view, expression is
11854 -- the syntactic copy on full view (which has been checked for
11855 -- conformance with partial view), only used here to post error
11859 D := First_Discriminant (T);
11860 New_D := First (Discriminant_Specifications (N));
11861 while Present (D) loop
11862 Prev_D := Current_Entity (D);
11863 Set_Current_Entity (D);
11864 Set_Is_Immediately_Visible (D);
11865 Set_Homonym (D, Prev_D);
11867 -- Handle the case where there is an untagged partial view and
11868 -- the full view is tagged: must disallow discriminants with
11869 -- defaults, unless compiling for Ada 2012, which allows a
11870 -- limited tagged type to have defaulted discriminants (see
11871 -- AI05-0214). However, suppress error here if it was already
11872 -- reported on the default expression of the partial view.
11874 if Is_Tagged_Type (T)
11875 and then Present (Expression (Parent (D)))
11876 and then (not Is_Limited_Type (Current_Scope)
11877 or else Ada_Version < Ada_2012)
11878 and then not Error_Posted (Expression (Parent (D)))
11880 if Ada_Version >= Ada_2012 then
11882 ("discriminants of nonlimited tagged type cannot have "
11884 Expression (New_D));
11887 ("discriminants of tagged type cannot have defaults",
11888 Expression (New_D));
11892 -- Ada 2005 (AI-230): Access discriminant allowed in
11893 -- non-limited record types.
11895 if Ada_Version < Ada_2005 then
11897 -- This restriction gets applied to the full type here. It
11898 -- has already been applied earlier to the partial view.
11900 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11903 Next_Discriminant (D);
11908 elsif Present (Discriminant_Specifications (N)) then
11909 Process_Discriminants (N, Prev);
11911 end Check_Or_Process_Discriminants;
11913 ----------------------
11914 -- Check_Real_Bound --
11915 ----------------------
11917 procedure Check_Real_Bound (Bound : Node_Id) is
11919 if not Is_Real_Type (Etype (Bound)) then
11921 ("bound in real type definition must be of real type", Bound);
11923 elsif not Is_OK_Static_Expression (Bound) then
11924 Flag_Non_Static_Expr
11925 ("non-static expression used for real type bound!", Bound);
11932 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11934 Resolve (Bound, Standard_Float);
11935 end Check_Real_Bound;
11937 ------------------------------
11938 -- Complete_Private_Subtype --
11939 ------------------------------
11941 procedure Complete_Private_Subtype
11944 Full_Base : Entity_Id;
11945 Related_Nod : Node_Id)
11947 Save_Next_Entity : Entity_Id;
11948 Save_Homonym : Entity_Id;
11951 -- Set semantic attributes for (implicit) private subtype completion.
11952 -- If the full type has no discriminants, then it is a copy of the
11953 -- full view of the base. Otherwise, it is a subtype of the base with
11954 -- a possible discriminant constraint. Save and restore the original
11955 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11956 -- not corrupt the entity chain.
11958 -- Note that the type of the full view is the same entity as the type
11959 -- of the partial view. In this fashion, the subtype has access to the
11960 -- correct view of the parent.
11962 Save_Next_Entity := Next_Entity (Full);
11963 Save_Homonym := Homonym (Priv);
11965 case Ekind (Full_Base) is
11966 when Class_Wide_Kind
11973 Copy_Node (Priv, Full);
11975 Set_Has_Discriminants
11976 (Full, Has_Discriminants (Full_Base));
11977 Set_Has_Unknown_Discriminants
11978 (Full, Has_Unknown_Discriminants (Full_Base));
11979 Set_First_Entity (Full, First_Entity (Full_Base));
11980 Set_Last_Entity (Full, Last_Entity (Full_Base));
11982 -- If the underlying base type is constrained, we know that the
11983 -- full view of the subtype is constrained as well (the converse
11984 -- is not necessarily true).
11986 if Is_Constrained (Full_Base) then
11987 Set_Is_Constrained (Full);
11991 Copy_Node (Full_Base, Full);
11993 Set_Chars (Full, Chars (Priv));
11994 Conditional_Delay (Full, Priv);
11995 Set_Sloc (Full, Sloc (Priv));
11998 Set_Next_Entity (Full, Save_Next_Entity);
11999 Set_Homonym (Full, Save_Homonym);
12000 Set_Associated_Node_For_Itype (Full, Related_Nod);
12002 -- Set common attributes for all subtypes: kind, convention, etc.
12004 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
12005 Set_Convention (Full, Convention (Full_Base));
12007 -- The Etype of the full view is inconsistent. Gigi needs to see the
12008 -- structural full view, which is what the current scheme gives: the
12009 -- Etype of the full view is the etype of the full base. However, if the
12010 -- full base is a derived type, the full view then looks like a subtype
12011 -- of the parent, not a subtype of the full base. If instead we write:
12013 -- Set_Etype (Full, Full_Base);
12015 -- then we get inconsistencies in the front-end (confusion between
12016 -- views). Several outstanding bugs are related to this ???
12018 Set_Is_First_Subtype (Full, False);
12019 Set_Scope (Full, Scope (Priv));
12020 Set_Size_Info (Full, Full_Base);
12021 Set_RM_Size (Full, RM_Size (Full_Base));
12022 Set_Is_Itype (Full);
12024 -- A subtype of a private-type-without-discriminants, whose full-view
12025 -- has discriminants with default expressions, is not constrained.
12027 if not Has_Discriminants (Priv) then
12028 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
12030 if Has_Discriminants (Full_Base) then
12031 Set_Discriminant_Constraint
12032 (Full, Discriminant_Constraint (Full_Base));
12034 -- The partial view may have been indefinite, the full view
12037 Set_Has_Unknown_Discriminants
12038 (Full, Has_Unknown_Discriminants (Full_Base));
12042 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
12043 Set_Depends_On_Private (Full, Has_Private_Component (Full));
12045 -- Freeze the private subtype entity if its parent is delayed, and not
12046 -- already frozen. We skip this processing if the type is an anonymous
12047 -- subtype of a record component, or is the corresponding record of a
12048 -- protected type, since these are processed when the enclosing type
12049 -- is frozen. If the parent type is declared in a nested package then
12050 -- the freezing of the private and full views also happens later.
12052 if not Is_Type (Scope (Full)) then
12054 and then In_Same_Source_Unit (Full, Full_Base)
12055 and then Scope (Full_Base) /= Scope (Full)
12057 Set_Has_Delayed_Freeze (Full);
12058 Set_Has_Delayed_Freeze (Priv);
12061 Set_Has_Delayed_Freeze (Full,
12062 Has_Delayed_Freeze (Full_Base)
12063 and then not Is_Frozen (Full_Base));
12067 Set_Freeze_Node (Full, Empty);
12068 Set_Is_Frozen (Full, False);
12069 Set_Full_View (Priv, Full);
12071 if Has_Discriminants (Full) then
12072 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
12073 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
12075 if Has_Unknown_Discriminants (Full) then
12076 Set_Discriminant_Constraint (Full, No_Elist);
12080 if Ekind (Full_Base) = E_Record_Type
12081 and then Has_Discriminants (Full_Base)
12082 and then Has_Discriminants (Priv) -- might not, if errors
12083 and then not Has_Unknown_Discriminants (Priv)
12084 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
12086 Create_Constrained_Components
12087 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
12089 -- If the full base is itself derived from private, build a congruent
12090 -- subtype of its underlying type, for use by the back end. For a
12091 -- constrained record component, the declaration cannot be placed on
12092 -- the component list, but it must nevertheless be built an analyzed, to
12093 -- supply enough information for Gigi to compute the size of component.
12095 elsif Ekind (Full_Base) in Private_Kind
12096 and then Is_Derived_Type (Full_Base)
12097 and then Has_Discriminants (Full_Base)
12098 and then (Ekind (Current_Scope) /= E_Record_Subtype)
12100 if not Is_Itype (Priv)
12102 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
12104 Build_Underlying_Full_View
12105 (Parent (Priv), Full, Etype (Full_Base));
12107 elsif Nkind (Related_Nod) = N_Component_Declaration then
12108 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
12111 elsif Is_Record_Type (Full_Base) then
12113 -- Show Full is simply a renaming of Full_Base
12115 Set_Cloned_Subtype (Full, Full_Base);
12118 -- It is unsafe to share the bounds of a scalar type, because the Itype
12119 -- is elaborated on demand, and if a bound is non-static then different
12120 -- orders of elaboration in different units will lead to different
12121 -- external symbols.
12123 if Is_Scalar_Type (Full_Base) then
12124 Set_Scalar_Range (Full,
12125 Make_Range (Sloc (Related_Nod),
12127 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
12129 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
12131 -- This completion inherits the bounds of the full parent, but if
12132 -- the parent is an unconstrained floating point type, so is the
12135 if Is_Floating_Point_Type (Full_Base) then
12136 Set_Includes_Infinities
12137 (Scalar_Range (Full), Has_Infinities (Full_Base));
12141 -- ??? It seems that a lot of fields are missing that should be copied
12142 -- from Full_Base to Full. Here are some that are introduced in a
12143 -- non-disruptive way but a cleanup is necessary.
12145 if Is_Tagged_Type (Full_Base) then
12146 Set_Is_Tagged_Type (Full);
12147 Set_Direct_Primitive_Operations
12148 (Full, Direct_Primitive_Operations (Full_Base));
12149 Set_No_Tagged_Streams_Pragma
12150 (Full, No_Tagged_Streams_Pragma (Full_Base));
12152 -- Inherit class_wide type of full_base in case the partial view was
12153 -- not tagged. Otherwise it has already been created when the private
12154 -- subtype was analyzed.
12156 if No (Class_Wide_Type (Full)) then
12157 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
12160 -- If this is a subtype of a protected or task type, constrain its
12161 -- corresponding record, unless this is a subtype without constraints,
12162 -- i.e. a simple renaming as with an actual subtype in an instance.
12164 elsif Is_Concurrent_Type (Full_Base) then
12165 if Has_Discriminants (Full)
12166 and then Present (Corresponding_Record_Type (Full_Base))
12168 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
12170 Set_Corresponding_Record_Type (Full,
12171 Constrain_Corresponding_Record
12172 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
12175 Set_Corresponding_Record_Type (Full,
12176 Corresponding_Record_Type (Full_Base));
12180 -- Link rep item chain, and also setting of Has_Predicates from private
12181 -- subtype to full subtype, since we will need these on the full subtype
12182 -- to create the predicate function. Note that the full subtype may
12183 -- already have rep items, inherited from the full view of the base
12184 -- type, so we must be sure not to overwrite these entries.
12189 Next_Item : Node_Id;
12190 Priv_Item : Node_Id;
12193 Item := First_Rep_Item (Full);
12194 Priv_Item := First_Rep_Item (Priv);
12196 -- If no existing rep items on full type, we can just link directly
12197 -- to the list of items on the private type, if any exist.. Same if
12198 -- the rep items are only those inherited from the base
12201 or else Nkind (Item) /= N_Aspect_Specification
12202 or else Entity (Item) = Full_Base)
12203 and then Present (First_Rep_Item (Priv))
12205 Set_First_Rep_Item (Full, Priv_Item);
12207 -- Otherwise, search to the end of items currently linked to the full
12208 -- subtype and append the private items to the end. However, if Priv
12209 -- and Full already have the same list of rep items, then the append
12210 -- is not done, as that would create a circularity.
12212 -- The partial view may have a predicate and the rep item lists of
12213 -- both views agree when inherited from the same ancestor. In that
12214 -- case, simply propagate the list from one view to the other.
12215 -- A more complex analysis needed here ???
12217 elsif Present (Priv_Item)
12218 and then Item = Next_Rep_Item (Priv_Item)
12220 Set_First_Rep_Item (Full, Priv_Item);
12222 elsif Item /= Priv_Item then
12225 Next_Item := Next_Rep_Item (Item);
12226 exit when No (Next_Item);
12229 -- If the private view has aspect specifications, the full view
12230 -- inherits them. Since these aspects may already have been
12231 -- attached to the full view during derivation, do not append
12232 -- them if already present.
12234 if Item = First_Rep_Item (Priv) then
12240 -- And link the private type items at the end of the chain
12243 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
12248 -- Make sure Has_Predicates is set on full type if it is set on the
12249 -- private type. Note that it may already be set on the full type and
12250 -- if so, we don't want to unset it. Similarly, propagate information
12251 -- about delayed aspects, because the corresponding pragmas must be
12252 -- analyzed when one of the views is frozen. This last step is needed
12253 -- in particular when the full type is a scalar type for which an
12254 -- anonymous base type is constructed.
12256 -- The predicate functions are generated either at the freeze point
12257 -- of the type or at the end of the visible part, and we must avoid
12258 -- generating them twice.
12260 if Has_Predicates (Priv) then
12261 Set_Has_Predicates (Full);
12263 if Present (Predicate_Function (Priv))
12264 and then No (Predicate_Function (Full))
12266 Set_Predicate_Function (Full, Predicate_Function (Priv));
12270 if Has_Delayed_Aspects (Priv) then
12271 Set_Has_Delayed_Aspects (Full);
12273 end Complete_Private_Subtype;
12275 ----------------------------
12276 -- Constant_Redeclaration --
12277 ----------------------------
12279 procedure Constant_Redeclaration
12284 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
12285 Obj_Def : constant Node_Id := Object_Definition (N);
12288 procedure Check_Possible_Deferred_Completion
12289 (Prev_Id : Entity_Id;
12290 Prev_Obj_Def : Node_Id;
12291 Curr_Obj_Def : Node_Id);
12292 -- Determine whether the two object definitions describe the partial
12293 -- and the full view of a constrained deferred constant. Generate
12294 -- a subtype for the full view and verify that it statically matches
12295 -- the subtype of the partial view.
12297 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12298 -- If deferred constant is an access type initialized with an allocator,
12299 -- check whether there is an illegal recursion in the definition,
12300 -- through a default value of some record subcomponent. This is normally
12301 -- detected when generating init procs, but requires this additional
12302 -- mechanism when expansion is disabled.
12304 ----------------------------------------
12305 -- Check_Possible_Deferred_Completion --
12306 ----------------------------------------
12308 procedure Check_Possible_Deferred_Completion
12309 (Prev_Id : Entity_Id;
12310 Prev_Obj_Def : Node_Id;
12311 Curr_Obj_Def : Node_Id)
12314 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12315 and then Present (Constraint (Prev_Obj_Def))
12316 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12317 and then Present (Constraint (Curr_Obj_Def))
12320 Loc : constant Source_Ptr := Sloc (N);
12321 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12322 Decl : constant Node_Id :=
12323 Make_Subtype_Declaration (Loc,
12324 Defining_Identifier => Def_Id,
12325 Subtype_Indication =>
12326 Relocate_Node (Curr_Obj_Def));
12329 Insert_Before_And_Analyze (N, Decl);
12330 Set_Etype (Id, Def_Id);
12332 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12333 Error_Msg_Sloc := Sloc (Prev_Id);
12334 Error_Msg_N ("subtype does not statically match deferred "
12335 & "declaration #", N);
12339 end Check_Possible_Deferred_Completion;
12341 ---------------------------------
12342 -- Check_Recursive_Declaration --
12343 ---------------------------------
12345 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12349 if Is_Record_Type (Typ) then
12350 Comp := First_Component (Typ);
12351 while Present (Comp) loop
12352 if Comes_From_Source (Comp) then
12353 if Present (Expression (Parent (Comp)))
12354 and then Is_Entity_Name (Expression (Parent (Comp)))
12355 and then Entity (Expression (Parent (Comp))) = Prev
12357 Error_Msg_Sloc := Sloc (Parent (Comp));
12359 ("illegal circularity with declaration for & #",
12363 elsif Is_Record_Type (Etype (Comp)) then
12364 Check_Recursive_Declaration (Etype (Comp));
12368 Next_Component (Comp);
12371 end Check_Recursive_Declaration;
12373 -- Start of processing for Constant_Redeclaration
12376 if Nkind (Parent (Prev)) = N_Object_Declaration then
12377 if Nkind (Object_Definition
12378 (Parent (Prev))) = N_Subtype_Indication
12380 -- Find type of new declaration. The constraints of the two
12381 -- views must match statically, but there is no point in
12382 -- creating an itype for the full view.
12384 if Nkind (Obj_Def) = N_Subtype_Indication then
12385 Find_Type (Subtype_Mark (Obj_Def));
12386 New_T := Entity (Subtype_Mark (Obj_Def));
12389 Find_Type (Obj_Def);
12390 New_T := Entity (Obj_Def);
12396 -- The full view may impose a constraint, even if the partial
12397 -- view does not, so construct the subtype.
12399 New_T := Find_Type_Of_Object (Obj_Def, N);
12404 -- Current declaration is illegal, diagnosed below in Enter_Name
12410 -- If previous full declaration or a renaming declaration exists, or if
12411 -- a homograph is present, let Enter_Name handle it, either with an
12412 -- error or with the removal of an overridden implicit subprogram.
12413 -- The previous one is a full declaration if it has an expression
12414 -- (which in the case of an aggregate is indicated by the Init flag).
12416 if Ekind (Prev) /= E_Constant
12417 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12418 or else Present (Expression (Parent (Prev)))
12419 or else Has_Init_Expression (Parent (Prev))
12420 or else Present (Full_View (Prev))
12424 -- Verify that types of both declarations match, or else that both types
12425 -- are anonymous access types whose designated subtypes statically match
12426 -- (as allowed in Ada 2005 by AI-385).
12428 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12430 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12431 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12432 or else Is_Access_Constant (Etype (New_T)) /=
12433 Is_Access_Constant (Etype (Prev))
12434 or else Can_Never_Be_Null (Etype (New_T)) /=
12435 Can_Never_Be_Null (Etype (Prev))
12436 or else Null_Exclusion_Present (Parent (Prev)) /=
12437 Null_Exclusion_Present (Parent (Id))
12438 or else not Subtypes_Statically_Match
12439 (Designated_Type (Etype (Prev)),
12440 Designated_Type (Etype (New_T))))
12442 Error_Msg_Sloc := Sloc (Prev);
12443 Error_Msg_N ("type does not match declaration#", N);
12444 Set_Full_View (Prev, Id);
12445 Set_Etype (Id, Any_Type);
12447 -- A deferred constant whose type is an anonymous array is always
12448 -- illegal (unless imported). A detailed error message might be
12449 -- helpful for Ada beginners.
12451 if Nkind (Object_Definition (Parent (Prev)))
12452 = N_Constrained_Array_Definition
12453 and then Nkind (Object_Definition (N))
12454 = N_Constrained_Array_Definition
12456 Error_Msg_N ("\each anonymous array is a distinct type", N);
12457 Error_Msg_N ("a deferred constant must have a named type",
12458 Object_Definition (Parent (Prev)));
12462 Null_Exclusion_Present (Parent (Prev))
12463 and then not Null_Exclusion_Present (N)
12465 Error_Msg_Sloc := Sloc (Prev);
12466 Error_Msg_N ("null-exclusion does not match declaration#", N);
12467 Set_Full_View (Prev, Id);
12468 Set_Etype (Id, Any_Type);
12470 -- If so, process the full constant declaration
12473 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12474 -- the deferred declaration is constrained, then the subtype defined
12475 -- by the subtype_indication in the full declaration shall match it
12478 Check_Possible_Deferred_Completion
12480 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12481 Curr_Obj_Def => Obj_Def);
12483 Set_Full_View (Prev, Id);
12484 Set_Is_Public (Id, Is_Public (Prev));
12485 Set_Is_Internal (Id);
12486 Append_Entity (Id, Current_Scope);
12488 -- Check ALIASED present if present before (RM 7.4(7))
12490 if Is_Aliased (Prev)
12491 and then not Aliased_Present (N)
12493 Error_Msg_Sloc := Sloc (Prev);
12494 Error_Msg_N ("ALIASED required (see declaration #)", N);
12497 -- Check that placement is in private part and that the incomplete
12498 -- declaration appeared in the visible part.
12500 if Ekind (Current_Scope) = E_Package
12501 and then not In_Private_Part (Current_Scope)
12503 Error_Msg_Sloc := Sloc (Prev);
12505 ("full constant for declaration # must be in private part", N);
12507 elsif Ekind (Current_Scope) = E_Package
12509 List_Containing (Parent (Prev)) /=
12510 Visible_Declarations (Package_Specification (Current_Scope))
12513 ("deferred constant must be declared in visible part",
12517 if Is_Access_Type (T)
12518 and then Nkind (Expression (N)) = N_Allocator
12520 Check_Recursive_Declaration (Designated_Type (T));
12523 -- A deferred constant is a visible entity. If type has invariants,
12524 -- verify that the initial value satisfies them.
12526 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12528 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12531 end Constant_Redeclaration;
12533 ----------------------
12534 -- Constrain_Access --
12535 ----------------------
12537 procedure Constrain_Access
12538 (Def_Id : in out Entity_Id;
12540 Related_Nod : Node_Id)
12542 T : constant Entity_Id := Entity (Subtype_Mark (S));
12543 Desig_Type : constant Entity_Id := Designated_Type (T);
12544 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12545 Constraint_OK : Boolean := True;
12548 if Is_Array_Type (Desig_Type) then
12549 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12551 elsif (Is_Record_Type (Desig_Type)
12552 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12553 and then not Is_Constrained (Desig_Type)
12555 -- ??? The following code is a temporary bypass to ignore a
12556 -- discriminant constraint on access type if it is constraining
12557 -- the current record. Avoid creating the implicit subtype of the
12558 -- record we are currently compiling since right now, we cannot
12559 -- handle these. For now, just return the access type itself.
12561 if Desig_Type = Current_Scope
12562 and then No (Def_Id)
12564 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12565 Def_Id := Entity (Subtype_Mark (S));
12567 -- This call added to ensure that the constraint is analyzed
12568 -- (needed for a B test). Note that we still return early from
12569 -- this procedure to avoid recursive processing. ???
12571 Constrain_Discriminated_Type
12572 (Desig_Subtype, S, Related_Nod, For_Access => True);
12576 -- Enforce rule that the constraint is illegal if there is an
12577 -- unconstrained view of the designated type. This means that the
12578 -- partial view (either a private type declaration or a derivation
12579 -- from a private type) has no discriminants. (Defect Report
12580 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12582 -- Rule updated for Ada 2005: The private type is said to have
12583 -- a constrained partial view, given that objects of the type
12584 -- can be declared. Furthermore, the rule applies to all access
12585 -- types, unlike the rule concerning default discriminants (see
12588 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12589 and then Has_Private_Declaration (Desig_Type)
12590 and then In_Open_Scopes (Scope (Desig_Type))
12591 and then Has_Discriminants (Desig_Type)
12594 Pack : constant Node_Id :=
12595 Unit_Declaration_Node (Scope (Desig_Type));
12600 if Nkind (Pack) = N_Package_Declaration then
12601 Decls := Visible_Declarations (Specification (Pack));
12602 Decl := First (Decls);
12603 while Present (Decl) loop
12604 if (Nkind (Decl) = N_Private_Type_Declaration
12605 and then Chars (Defining_Identifier (Decl)) =
12606 Chars (Desig_Type))
12609 (Nkind (Decl) = N_Full_Type_Declaration
12611 Chars (Defining_Identifier (Decl)) =
12613 and then Is_Derived_Type (Desig_Type)
12615 Has_Private_Declaration (Etype (Desig_Type)))
12617 if No (Discriminant_Specifications (Decl)) then
12619 ("cannot constrain access type if designated "
12620 & "type has constrained partial view", S);
12632 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12633 For_Access => True);
12635 elsif Is_Concurrent_Type (Desig_Type)
12636 and then not Is_Constrained (Desig_Type)
12638 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12641 Error_Msg_N ("invalid constraint on access type", S);
12643 -- We simply ignore an invalid constraint
12645 Desig_Subtype := Desig_Type;
12646 Constraint_OK := False;
12649 if No (Def_Id) then
12650 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12652 Set_Ekind (Def_Id, E_Access_Subtype);
12655 if Constraint_OK then
12656 Set_Etype (Def_Id, Base_Type (T));
12658 if Is_Private_Type (Desig_Type) then
12659 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12662 Set_Etype (Def_Id, Any_Type);
12665 Set_Size_Info (Def_Id, T);
12666 Set_Is_Constrained (Def_Id, Constraint_OK);
12667 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12668 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12669 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12671 Conditional_Delay (Def_Id, T);
12673 -- AI-363 : Subtypes of general access types whose designated types have
12674 -- default discriminants are disallowed. In instances, the rule has to
12675 -- be checked against the actual, of which T is the subtype. In a
12676 -- generic body, the rule is checked assuming that the actual type has
12677 -- defaulted discriminants.
12679 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12680 if Ekind (Base_Type (T)) = E_General_Access_Type
12681 and then Has_Defaulted_Discriminants (Desig_Type)
12683 if Ada_Version < Ada_2005 then
12685 ("access subtype of general access type would not " &
12686 "be allowed in Ada 2005?y?", S);
12689 ("access subtype of general access type not allowed", S);
12692 Error_Msg_N ("\discriminants have defaults", S);
12694 elsif Is_Access_Type (T)
12695 and then Is_Generic_Type (Desig_Type)
12696 and then Has_Discriminants (Desig_Type)
12697 and then In_Package_Body (Current_Scope)
12699 if Ada_Version < Ada_2005 then
12701 ("access subtype would not be allowed in generic body "
12702 & "in Ada 2005?y?", S);
12705 ("access subtype not allowed in generic body", S);
12709 ("\designated type is a discriminated formal", S);
12712 end Constrain_Access;
12714 ---------------------
12715 -- Constrain_Array --
12716 ---------------------
12718 procedure Constrain_Array
12719 (Def_Id : in out Entity_Id;
12721 Related_Nod : Node_Id;
12722 Related_Id : Entity_Id;
12723 Suffix : Character)
12725 C : constant Node_Id := Constraint (SI);
12726 Number_Of_Constraints : Nat := 0;
12729 Constraint_OK : Boolean := True;
12732 T := Entity (Subtype_Mark (SI));
12734 if Is_Access_Type (T) then
12735 T := Designated_Type (T);
12738 -- If an index constraint follows a subtype mark in a subtype indication
12739 -- then the type or subtype denoted by the subtype mark must not already
12740 -- impose an index constraint. The subtype mark must denote either an
12741 -- unconstrained array type or an access type whose designated type
12742 -- is such an array type... (RM 3.6.1)
12744 if Is_Constrained (T) then
12745 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12746 Constraint_OK := False;
12749 S := First (Constraints (C));
12750 while Present (S) loop
12751 Number_Of_Constraints := Number_Of_Constraints + 1;
12755 -- In either case, the index constraint must provide a discrete
12756 -- range for each index of the array type and the type of each
12757 -- discrete range must be the same as that of the corresponding
12758 -- index. (RM 3.6.1)
12760 if Number_Of_Constraints /= Number_Dimensions (T) then
12761 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12762 Constraint_OK := False;
12765 S := First (Constraints (C));
12766 Index := First_Index (T);
12769 -- Apply constraints to each index type
12771 for J in 1 .. Number_Of_Constraints loop
12772 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12780 if No (Def_Id) then
12782 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12783 Set_Parent (Def_Id, Related_Nod);
12786 Set_Ekind (Def_Id, E_Array_Subtype);
12789 Set_Size_Info (Def_Id, (T));
12790 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12791 Set_Etype (Def_Id, Base_Type (T));
12793 if Constraint_OK then
12794 Set_First_Index (Def_Id, First (Constraints (C)));
12796 Set_First_Index (Def_Id, First_Index (T));
12799 Set_Is_Constrained (Def_Id, True);
12800 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12801 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12803 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12804 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12806 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12807 -- We need to initialize the attribute because if Def_Id is previously
12808 -- analyzed through a limited_with clause, it will have the attributes
12809 -- of an incomplete type, one of which is an Elist that overlaps the
12810 -- Packed_Array_Impl_Type field.
12812 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12814 -- Build a freeze node if parent still needs one. Also make sure that
12815 -- the Depends_On_Private status is set because the subtype will need
12816 -- reprocessing at the time the base type does, and also we must set a
12817 -- conditional delay.
12819 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12820 Conditional_Delay (Def_Id, T);
12821 end Constrain_Array;
12823 ------------------------------
12824 -- Constrain_Component_Type --
12825 ------------------------------
12827 function Constrain_Component_Type
12829 Constrained_Typ : Entity_Id;
12830 Related_Node : Node_Id;
12832 Constraints : Elist_Id) return Entity_Id
12834 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12835 Compon_Type : constant Entity_Id := Etype (Comp);
12837 function Build_Constrained_Array_Type
12838 (Old_Type : Entity_Id) return Entity_Id;
12839 -- If Old_Type is an array type, one of whose indexes is constrained
12840 -- by a discriminant, build an Itype whose constraint replaces the
12841 -- discriminant with its value in the constraint.
12843 function Build_Constrained_Discriminated_Type
12844 (Old_Type : Entity_Id) return Entity_Id;
12845 -- Ditto for record components
12847 function Build_Constrained_Access_Type
12848 (Old_Type : Entity_Id) return Entity_Id;
12849 -- Ditto for access types. Makes use of previous two functions, to
12850 -- constrain designated type.
12852 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12853 -- T is an array or discriminated type, C is a list of constraints
12854 -- that apply to T. This routine builds the constrained subtype.
12856 function Is_Discriminant (Expr : Node_Id) return Boolean;
12857 -- Returns True if Expr is a discriminant
12859 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12860 -- Find the value of discriminant Discrim in Constraint
12862 -----------------------------------
12863 -- Build_Constrained_Access_Type --
12864 -----------------------------------
12866 function Build_Constrained_Access_Type
12867 (Old_Type : Entity_Id) return Entity_Id
12869 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12871 Desig_Subtype : Entity_Id;
12875 -- if the original access type was not embedded in the enclosing
12876 -- type definition, there is no need to produce a new access
12877 -- subtype. In fact every access type with an explicit constraint
12878 -- generates an itype whose scope is the enclosing record.
12880 if not Is_Type (Scope (Old_Type)) then
12883 elsif Is_Array_Type (Desig_Type) then
12884 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12886 elsif Has_Discriminants (Desig_Type) then
12888 -- This may be an access type to an enclosing record type for
12889 -- which we are constructing the constrained components. Return
12890 -- the enclosing record subtype. This is not always correct,
12891 -- but avoids infinite recursion. ???
12893 Desig_Subtype := Any_Type;
12895 for J in reverse 0 .. Scope_Stack.Last loop
12896 Scop := Scope_Stack.Table (J).Entity;
12899 and then Base_Type (Scop) = Base_Type (Desig_Type)
12901 Desig_Subtype := Scop;
12904 exit when not Is_Type (Scop);
12907 if Desig_Subtype = Any_Type then
12909 Build_Constrained_Discriminated_Type (Desig_Type);
12916 if Desig_Subtype /= Desig_Type then
12918 -- The Related_Node better be here or else we won't be able
12919 -- to attach new itypes to a node in the tree.
12921 pragma Assert (Present (Related_Node));
12923 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12925 Set_Etype (Itype, Base_Type (Old_Type));
12926 Set_Size_Info (Itype, (Old_Type));
12927 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12928 Set_Depends_On_Private (Itype, Has_Private_Component
12930 Set_Is_Access_Constant (Itype, Is_Access_Constant
12933 -- The new itype needs freezing when it depends on a not frozen
12934 -- type and the enclosing subtype needs freezing.
12936 if Has_Delayed_Freeze (Constrained_Typ)
12937 and then not Is_Frozen (Constrained_Typ)
12939 Conditional_Delay (Itype, Base_Type (Old_Type));
12947 end Build_Constrained_Access_Type;
12949 ----------------------------------
12950 -- Build_Constrained_Array_Type --
12951 ----------------------------------
12953 function Build_Constrained_Array_Type
12954 (Old_Type : Entity_Id) return Entity_Id
12958 Old_Index : Node_Id;
12959 Range_Node : Node_Id;
12960 Constr_List : List_Id;
12962 Need_To_Create_Itype : Boolean := False;
12965 Old_Index := First_Index (Old_Type);
12966 while Present (Old_Index) loop
12967 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12969 if Is_Discriminant (Lo_Expr)
12971 Is_Discriminant (Hi_Expr)
12973 Need_To_Create_Itype := True;
12976 Next_Index (Old_Index);
12979 if Need_To_Create_Itype then
12980 Constr_List := New_List;
12982 Old_Index := First_Index (Old_Type);
12983 while Present (Old_Index) loop
12984 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12986 if Is_Discriminant (Lo_Expr) then
12987 Lo_Expr := Get_Discr_Value (Lo_Expr);
12990 if Is_Discriminant (Hi_Expr) then
12991 Hi_Expr := Get_Discr_Value (Hi_Expr);
12996 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12998 Append (Range_Node, To => Constr_List);
13000 Next_Index (Old_Index);
13003 return Build_Subtype (Old_Type, Constr_List);
13008 end Build_Constrained_Array_Type;
13010 ------------------------------------------
13011 -- Build_Constrained_Discriminated_Type --
13012 ------------------------------------------
13014 function Build_Constrained_Discriminated_Type
13015 (Old_Type : Entity_Id) return Entity_Id
13018 Constr_List : List_Id;
13019 Old_Constraint : Elmt_Id;
13021 Need_To_Create_Itype : Boolean := False;
13024 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13025 while Present (Old_Constraint) loop
13026 Expr := Node (Old_Constraint);
13028 if Is_Discriminant (Expr) then
13029 Need_To_Create_Itype := True;
13032 Next_Elmt (Old_Constraint);
13035 if Need_To_Create_Itype then
13036 Constr_List := New_List;
13038 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
13039 while Present (Old_Constraint) loop
13040 Expr := Node (Old_Constraint);
13042 if Is_Discriminant (Expr) then
13043 Expr := Get_Discr_Value (Expr);
13046 Append (New_Copy_Tree (Expr), To => Constr_List);
13048 Next_Elmt (Old_Constraint);
13051 return Build_Subtype (Old_Type, Constr_List);
13056 end Build_Constrained_Discriminated_Type;
13058 -------------------
13059 -- Build_Subtype --
13060 -------------------
13062 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
13064 Subtyp_Decl : Node_Id;
13065 Def_Id : Entity_Id;
13066 Btyp : Entity_Id := Base_Type (T);
13069 -- The Related_Node better be here or else we won't be able to
13070 -- attach new itypes to a node in the tree.
13072 pragma Assert (Present (Related_Node));
13074 -- If the view of the component's type is incomplete or private
13075 -- with unknown discriminants, then the constraint must be applied
13076 -- to the full type.
13078 if Has_Unknown_Discriminants (Btyp)
13079 and then Present (Underlying_Type (Btyp))
13081 Btyp := Underlying_Type (Btyp);
13085 Make_Subtype_Indication (Loc,
13086 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
13087 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
13089 Def_Id := Create_Itype (Ekind (T), Related_Node);
13092 Make_Subtype_Declaration (Loc,
13093 Defining_Identifier => Def_Id,
13094 Subtype_Indication => Indic);
13096 Set_Parent (Subtyp_Decl, Parent (Related_Node));
13098 -- Itypes must be analyzed with checks off (see package Itypes)
13100 Analyze (Subtyp_Decl, Suppress => All_Checks);
13105 ---------------------
13106 -- Get_Discr_Value --
13107 ---------------------
13109 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
13114 -- The discriminant may be declared for the type, in which case we
13115 -- find it by iterating over the list of discriminants. If the
13116 -- discriminant is inherited from a parent type, it appears as the
13117 -- corresponding discriminant of the current type. This will be the
13118 -- case when constraining an inherited component whose constraint is
13119 -- given by a discriminant of the parent.
13121 D := First_Discriminant (Typ);
13122 E := First_Elmt (Constraints);
13124 while Present (D) loop
13125 if D = Entity (Discrim)
13126 or else D = CR_Discriminant (Entity (Discrim))
13127 or else Corresponding_Discriminant (D) = Entity (Discrim)
13132 Next_Discriminant (D);
13136 -- The Corresponding_Discriminant mechanism is incomplete, because
13137 -- the correspondence between new and old discriminants is not one
13138 -- to one: one new discriminant can constrain several old ones. In
13139 -- that case, scan sequentially the stored_constraint, the list of
13140 -- discriminants of the parents, and the constraints.
13142 -- Previous code checked for the present of the Stored_Constraint
13143 -- list for the derived type, but did not use it at all. Should it
13144 -- be present when the component is a discriminated task type?
13146 if Is_Derived_Type (Typ)
13147 and then Scope (Entity (Discrim)) = Etype (Typ)
13149 D := First_Discriminant (Etype (Typ));
13150 E := First_Elmt (Constraints);
13151 while Present (D) loop
13152 if D = Entity (Discrim) then
13156 Next_Discriminant (D);
13161 -- Something is wrong if we did not find the value
13163 raise Program_Error;
13164 end Get_Discr_Value;
13166 ---------------------
13167 -- Is_Discriminant --
13168 ---------------------
13170 function Is_Discriminant (Expr : Node_Id) return Boolean is
13171 Discrim_Scope : Entity_Id;
13174 if Denotes_Discriminant (Expr) then
13175 Discrim_Scope := Scope (Entity (Expr));
13177 -- Either we have a reference to one of Typ's discriminants,
13179 pragma Assert (Discrim_Scope = Typ
13181 -- or to the discriminants of the parent type, in the case
13182 -- of a derivation of a tagged type with variants.
13184 or else Discrim_Scope = Etype (Typ)
13185 or else Full_View (Discrim_Scope) = Etype (Typ)
13187 -- or same as above for the case where the discriminants
13188 -- were declared in Typ's private view.
13190 or else (Is_Private_Type (Discrim_Scope)
13191 and then Chars (Discrim_Scope) = Chars (Typ))
13193 -- or else we are deriving from the full view and the
13194 -- discriminant is declared in the private entity.
13196 or else (Is_Private_Type (Typ)
13197 and then Chars (Discrim_Scope) = Chars (Typ))
13199 -- Or we are constrained the corresponding record of a
13200 -- synchronized type that completes a private declaration.
13202 or else (Is_Concurrent_Record_Type (Typ)
13204 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
13206 -- or we have a class-wide type, in which case make sure the
13207 -- discriminant found belongs to the root type.
13209 or else (Is_Class_Wide_Type (Typ)
13210 and then Etype (Typ) = Discrim_Scope));
13215 -- In all other cases we have something wrong
13218 end Is_Discriminant;
13220 -- Start of processing for Constrain_Component_Type
13223 if Nkind (Parent (Comp)) = N_Component_Declaration
13224 and then Comes_From_Source (Parent (Comp))
13225 and then Comes_From_Source
13226 (Subtype_Indication (Component_Definition (Parent (Comp))))
13229 (Subtype_Indication (Component_Definition (Parent (Comp))))
13231 return Compon_Type;
13233 elsif Is_Array_Type (Compon_Type) then
13234 return Build_Constrained_Array_Type (Compon_Type);
13236 elsif Has_Discriminants (Compon_Type) then
13237 return Build_Constrained_Discriminated_Type (Compon_Type);
13239 elsif Is_Access_Type (Compon_Type) then
13240 return Build_Constrained_Access_Type (Compon_Type);
13243 return Compon_Type;
13245 end Constrain_Component_Type;
13247 --------------------------
13248 -- Constrain_Concurrent --
13249 --------------------------
13251 -- For concurrent types, the associated record value type carries the same
13252 -- discriminants, so when we constrain a concurrent type, we must constrain
13253 -- the corresponding record type as well.
13255 procedure Constrain_Concurrent
13256 (Def_Id : in out Entity_Id;
13258 Related_Nod : Node_Id;
13259 Related_Id : Entity_Id;
13260 Suffix : Character)
13262 -- Retrieve Base_Type to ensure getting to the concurrent type in the
13263 -- case of a private subtype (needed when only doing semantic analysis).
13265 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
13269 if Is_Access_Type (T_Ent) then
13270 T_Ent := Designated_Type (T_Ent);
13273 T_Val := Corresponding_Record_Type (T_Ent);
13275 if Present (T_Val) then
13277 if No (Def_Id) then
13278 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13280 -- Elaborate itype now, as it may be used in a subsequent
13281 -- synchronized operation in another scope.
13283 if Nkind (Related_Nod) = N_Full_Type_Declaration then
13284 Build_Itype_Reference (Def_Id, Related_Nod);
13288 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13290 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13291 Set_Corresponding_Record_Type (Def_Id,
13292 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13295 -- If there is no associated record, expansion is disabled and this
13296 -- is a generic context. Create a subtype in any case, so that
13297 -- semantic analysis can proceed.
13299 if No (Def_Id) then
13300 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13303 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13305 end Constrain_Concurrent;
13307 ------------------------------------
13308 -- Constrain_Corresponding_Record --
13309 ------------------------------------
13311 function Constrain_Corresponding_Record
13312 (Prot_Subt : Entity_Id;
13313 Corr_Rec : Entity_Id;
13314 Related_Nod : Node_Id) return Entity_Id
13316 T_Sub : constant Entity_Id :=
13317 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13320 Set_Etype (T_Sub, Corr_Rec);
13321 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13322 Set_Is_Constrained (T_Sub, True);
13323 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13324 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13326 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13327 Set_Discriminant_Constraint
13328 (T_Sub, Discriminant_Constraint (Prot_Subt));
13329 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13330 Create_Constrained_Components
13331 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13334 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13336 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13337 Conditional_Delay (T_Sub, Corr_Rec);
13340 -- This is a component subtype: it will be frozen in the context of
13341 -- the enclosing record's init_proc, so that discriminant references
13342 -- are resolved to discriminals. (Note: we used to skip freezing
13343 -- altogether in that case, which caused errors downstream for
13344 -- components of a bit packed array type).
13346 Set_Has_Delayed_Freeze (T_Sub);
13350 end Constrain_Corresponding_Record;
13352 -----------------------
13353 -- Constrain_Decimal --
13354 -----------------------
13356 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13357 T : constant Entity_Id := Entity (Subtype_Mark (S));
13358 C : constant Node_Id := Constraint (S);
13359 Loc : constant Source_Ptr := Sloc (C);
13360 Range_Expr : Node_Id;
13361 Digits_Expr : Node_Id;
13366 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13368 if Nkind (C) = N_Range_Constraint then
13369 Range_Expr := Range_Expression (C);
13370 Digits_Val := Digits_Value (T);
13373 pragma Assert (Nkind (C) = N_Digits_Constraint);
13375 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13377 Digits_Expr := Digits_Expression (C);
13378 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13380 Check_Digits_Expression (Digits_Expr);
13381 Digits_Val := Expr_Value (Digits_Expr);
13383 if Digits_Val > Digits_Value (T) then
13385 ("digits expression is incompatible with subtype", C);
13386 Digits_Val := Digits_Value (T);
13389 if Present (Range_Constraint (C)) then
13390 Range_Expr := Range_Expression (Range_Constraint (C));
13392 Range_Expr := Empty;
13396 Set_Etype (Def_Id, Base_Type (T));
13397 Set_Size_Info (Def_Id, (T));
13398 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13399 Set_Delta_Value (Def_Id, Delta_Value (T));
13400 Set_Scale_Value (Def_Id, Scale_Value (T));
13401 Set_Small_Value (Def_Id, Small_Value (T));
13402 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13403 Set_Digits_Value (Def_Id, Digits_Val);
13405 -- Manufacture range from given digits value if no range present
13407 if No (Range_Expr) then
13408 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13412 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13414 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13417 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13418 Set_Discrete_RM_Size (Def_Id);
13420 -- Unconditionally delay the freeze, since we cannot set size
13421 -- information in all cases correctly until the freeze point.
13423 Set_Has_Delayed_Freeze (Def_Id);
13424 end Constrain_Decimal;
13426 ----------------------------------
13427 -- Constrain_Discriminated_Type --
13428 ----------------------------------
13430 procedure Constrain_Discriminated_Type
13431 (Def_Id : Entity_Id;
13433 Related_Nod : Node_Id;
13434 For_Access : Boolean := False)
13436 E : Entity_Id := Entity (Subtype_Mark (S));
13439 procedure Fixup_Bad_Constraint;
13440 -- Called after finding a bad constraint, and after having posted an
13441 -- appropriate error message. The goal is to leave type Def_Id in as
13442 -- reasonable state as possible.
13444 --------------------------
13445 -- Fixup_Bad_Constraint --
13446 --------------------------
13448 procedure Fixup_Bad_Constraint is
13450 -- Set a reasonable Ekind for the entity. For an incomplete type,
13451 -- we can't do much, but for other types, we can set the proper
13452 -- corresponding subtype kind.
13454 if Ekind (T) = E_Incomplete_Type then
13455 Set_Ekind (Def_Id, Ekind (T));
13457 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13460 -- Set Etype to the known type, to reduce chances of cascaded errors
13462 Set_Etype (Def_Id, E);
13463 Set_Error_Posted (Def_Id);
13464 end Fixup_Bad_Constraint;
13469 Constr : Elist_Id := New_Elmt_List;
13471 -- Start of processing for Constrain_Discriminated_Type
13474 C := Constraint (S);
13476 -- A discriminant constraint is only allowed in a subtype indication,
13477 -- after a subtype mark. This subtype mark must denote either a type
13478 -- with discriminants, or an access type whose designated type is a
13479 -- type with discriminants. A discriminant constraint specifies the
13480 -- values of these discriminants (RM 3.7.2(5)).
13482 T := Base_Type (Entity (Subtype_Mark (S)));
13484 if Is_Access_Type (T) then
13485 T := Designated_Type (T);
13488 -- In an instance it may be necessary to retrieve the full view of a
13489 -- type with unknown discriminants, or a full view with defaulted
13490 -- discriminants. In other contexts the constraint is illegal.
13493 and then Is_Private_Type (T)
13494 and then Present (Full_View (T))
13496 (Has_Unknown_Discriminants (T)
13498 (not Has_Discriminants (T)
13499 and then Has_Discriminants (Full_View (T))
13500 and then Present (Discriminant_Default_Value
13501 (First_Discriminant (Full_View (T))))))
13503 T := Full_View (T);
13504 E := Full_View (E);
13507 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13508 -- generating an error for access-to-incomplete subtypes.
13510 if Ada_Version >= Ada_2005
13511 and then Ekind (T) = E_Incomplete_Type
13512 and then Nkind (Parent (S)) = N_Subtype_Declaration
13513 and then not Is_Itype (Def_Id)
13515 -- A little sanity check: emit an error message if the type has
13516 -- discriminants to begin with. Type T may be a regular incomplete
13517 -- type or imported via a limited with clause.
13519 if Has_Discriminants (T)
13520 or else (From_Limited_With (T)
13521 and then Present (Non_Limited_View (T))
13522 and then Nkind (Parent (Non_Limited_View (T))) =
13523 N_Full_Type_Declaration
13524 and then Present (Discriminant_Specifications
13525 (Parent (Non_Limited_View (T)))))
13528 ("(Ada 2005) incomplete subtype may not be constrained", C);
13530 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13533 Fixup_Bad_Constraint;
13536 -- Check that the type has visible discriminants. The type may be
13537 -- a private type with unknown discriminants whose full view has
13538 -- discriminants which are invisible.
13540 elsif not Has_Discriminants (T)
13542 (Has_Unknown_Discriminants (T)
13543 and then Is_Private_Type (T))
13545 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13546 Fixup_Bad_Constraint;
13549 elsif Is_Constrained (E)
13550 or else (Ekind (E) = E_Class_Wide_Subtype
13551 and then Present (Discriminant_Constraint (E)))
13553 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13554 Fixup_Bad_Constraint;
13558 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13559 -- applies to the base type.
13561 T := Base_Type (T);
13563 Constr := Build_Discriminant_Constraints (T, S);
13565 -- If the list returned was empty we had an error in building the
13566 -- discriminant constraint. We have also already signalled an error
13567 -- in the incomplete type case
13569 if Is_Empty_Elmt_List (Constr) then
13570 Fixup_Bad_Constraint;
13574 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13575 end Constrain_Discriminated_Type;
13577 ---------------------------
13578 -- Constrain_Enumeration --
13579 ---------------------------
13581 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13582 T : constant Entity_Id := Entity (Subtype_Mark (S));
13583 C : constant Node_Id := Constraint (S);
13586 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13588 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13590 Set_Etype (Def_Id, Base_Type (T));
13591 Set_Size_Info (Def_Id, (T));
13592 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13593 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13595 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13597 Set_Discrete_RM_Size (Def_Id);
13598 end Constrain_Enumeration;
13600 ----------------------
13601 -- Constrain_Float --
13602 ----------------------
13604 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13605 T : constant Entity_Id := Entity (Subtype_Mark (S));
13611 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13613 Set_Etype (Def_Id, Base_Type (T));
13614 Set_Size_Info (Def_Id, (T));
13615 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13617 -- Process the constraint
13619 C := Constraint (S);
13621 -- Digits constraint present
13623 if Nkind (C) = N_Digits_Constraint then
13625 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13626 Check_Restriction (No_Obsolescent_Features, C);
13628 if Warn_On_Obsolescent_Feature then
13630 ("subtype digits constraint is an " &
13631 "obsolescent feature (RM J.3(8))?j?", C);
13634 D := Digits_Expression (C);
13635 Analyze_And_Resolve (D, Any_Integer);
13636 Check_Digits_Expression (D);
13637 Set_Digits_Value (Def_Id, Expr_Value (D));
13639 -- Check that digits value is in range. Obviously we can do this
13640 -- at compile time, but it is strictly a runtime check, and of
13641 -- course there is an ACVC test that checks this.
13643 if Digits_Value (Def_Id) > Digits_Value (T) then
13644 Error_Msg_Uint_1 := Digits_Value (T);
13645 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13647 Make_Raise_Constraint_Error (Sloc (D),
13648 Reason => CE_Range_Check_Failed);
13649 Insert_Action (Declaration_Node (Def_Id), Rais);
13652 C := Range_Constraint (C);
13654 -- No digits constraint present
13657 Set_Digits_Value (Def_Id, Digits_Value (T));
13660 -- Range constraint present
13662 if Nkind (C) = N_Range_Constraint then
13663 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13665 -- No range constraint present
13668 pragma Assert (No (C));
13669 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13672 Set_Is_Constrained (Def_Id);
13673 end Constrain_Float;
13675 ---------------------
13676 -- Constrain_Index --
13677 ---------------------
13679 procedure Constrain_Index
13682 Related_Nod : Node_Id;
13683 Related_Id : Entity_Id;
13684 Suffix : Character;
13685 Suffix_Index : Nat)
13687 Def_Id : Entity_Id;
13688 R : Node_Id := Empty;
13689 T : constant Entity_Id := Etype (Index);
13693 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13694 Set_Etype (Def_Id, Base_Type (T));
13696 if Nkind (S) = N_Range
13698 (Nkind (S) = N_Attribute_Reference
13699 and then Attribute_Name (S) = Name_Range)
13701 -- A Range attribute will be transformed into N_Range by Resolve
13707 Process_Range_Expr_In_Decl (R, T);
13709 if not Error_Posted (S)
13711 (Nkind (S) /= N_Range
13712 or else not Covers (T, (Etype (Low_Bound (S))))
13713 or else not Covers (T, (Etype (High_Bound (S)))))
13715 if Base_Type (T) /= Any_Type
13716 and then Etype (Low_Bound (S)) /= Any_Type
13717 and then Etype (High_Bound (S)) /= Any_Type
13719 Error_Msg_N ("range expected", S);
13723 elsif Nkind (S) = N_Subtype_Indication then
13725 -- The parser has verified that this is a discrete indication
13727 Resolve_Discrete_Subtype_Indication (S, T);
13728 Bad_Predicated_Subtype_Use
13729 ("subtype& has predicate, not allowed in index constraint",
13730 S, Entity (Subtype_Mark (S)));
13732 R := Range_Expression (Constraint (S));
13734 -- Capture values of bounds and generate temporaries for them if
13735 -- needed, since checks may cause duplication of the expressions
13736 -- which must not be reevaluated.
13738 -- The forced evaluation removes side effects from expressions, which
13739 -- should occur also in GNATprove mode. Otherwise, we end up with
13740 -- unexpected insertions of actions at places where this is not
13741 -- supposed to occur, e.g. on default parameters of a call.
13743 if Expander_Active or GNATprove_Mode then
13745 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13747 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13750 elsif Nkind (S) = N_Discriminant_Association then
13752 -- Syntactically valid in subtype indication
13754 Error_Msg_N ("invalid index constraint", S);
13755 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13758 -- Subtype_Mark case, no anonymous subtypes to construct
13763 if Is_Entity_Name (S) then
13764 if not Is_Type (Entity (S)) then
13765 Error_Msg_N ("expect subtype mark for index constraint", S);
13767 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13768 Wrong_Type (S, Base_Type (T));
13770 -- Check error of subtype with predicate in index constraint
13773 Bad_Predicated_Subtype_Use
13774 ("subtype& has predicate, not allowed in index constraint",
13781 Error_Msg_N ("invalid index constraint", S);
13782 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13787 -- Complete construction of the Itype
13789 if Is_Modular_Integer_Type (T) then
13790 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13792 elsif Is_Integer_Type (T) then
13793 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13796 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13797 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13798 Set_First_Literal (Def_Id, First_Literal (T));
13801 Set_Size_Info (Def_Id, (T));
13802 Set_RM_Size (Def_Id, RM_Size (T));
13803 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13805 Set_Scalar_Range (Def_Id, R);
13807 Set_Etype (S, Def_Id);
13808 Set_Discrete_RM_Size (Def_Id);
13809 end Constrain_Index;
13811 -----------------------
13812 -- Constrain_Integer --
13813 -----------------------
13815 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13816 T : constant Entity_Id := Entity (Subtype_Mark (S));
13817 C : constant Node_Id := Constraint (S);
13820 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13822 if Is_Modular_Integer_Type (T) then
13823 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13825 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13828 Set_Etype (Def_Id, Base_Type (T));
13829 Set_Size_Info (Def_Id, (T));
13830 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13831 Set_Discrete_RM_Size (Def_Id);
13832 end Constrain_Integer;
13834 ------------------------------
13835 -- Constrain_Ordinary_Fixed --
13836 ------------------------------
13838 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13839 T : constant Entity_Id := Entity (Subtype_Mark (S));
13845 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13846 Set_Etype (Def_Id, Base_Type (T));
13847 Set_Size_Info (Def_Id, (T));
13848 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13849 Set_Small_Value (Def_Id, Small_Value (T));
13851 -- Process the constraint
13853 C := Constraint (S);
13855 -- Delta constraint present
13857 if Nkind (C) = N_Delta_Constraint then
13859 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13860 Check_Restriction (No_Obsolescent_Features, C);
13862 if Warn_On_Obsolescent_Feature then
13864 ("subtype delta constraint is an " &
13865 "obsolescent feature (RM J.3(7))?j?");
13868 D := Delta_Expression (C);
13869 Analyze_And_Resolve (D, Any_Real);
13870 Check_Delta_Expression (D);
13871 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13873 -- Check that delta value is in range. Obviously we can do this
13874 -- at compile time, but it is strictly a runtime check, and of
13875 -- course there is an ACVC test that checks this.
13877 if Delta_Value (Def_Id) < Delta_Value (T) then
13878 Error_Msg_N ("??delta value is too small", D);
13880 Make_Raise_Constraint_Error (Sloc (D),
13881 Reason => CE_Range_Check_Failed);
13882 Insert_Action (Declaration_Node (Def_Id), Rais);
13885 C := Range_Constraint (C);
13887 -- No delta constraint present
13890 Set_Delta_Value (Def_Id, Delta_Value (T));
13893 -- Range constraint present
13895 if Nkind (C) = N_Range_Constraint then
13896 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13898 -- No range constraint present
13901 pragma Assert (No (C));
13902 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13905 Set_Discrete_RM_Size (Def_Id);
13907 -- Unconditionally delay the freeze, since we cannot set size
13908 -- information in all cases correctly until the freeze point.
13910 Set_Has_Delayed_Freeze (Def_Id);
13911 end Constrain_Ordinary_Fixed;
13913 -----------------------
13914 -- Contain_Interface --
13915 -----------------------
13917 function Contain_Interface
13918 (Iface : Entity_Id;
13919 Ifaces : Elist_Id) return Boolean
13921 Iface_Elmt : Elmt_Id;
13924 if Present (Ifaces) then
13925 Iface_Elmt := First_Elmt (Ifaces);
13926 while Present (Iface_Elmt) loop
13927 if Node (Iface_Elmt) = Iface then
13931 Next_Elmt (Iface_Elmt);
13936 end Contain_Interface;
13938 ---------------------------
13939 -- Convert_Scalar_Bounds --
13940 ---------------------------
13942 procedure Convert_Scalar_Bounds
13944 Parent_Type : Entity_Id;
13945 Derived_Type : Entity_Id;
13948 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13955 -- Defend against previous errors
13957 if No (Scalar_Range (Derived_Type)) then
13958 Check_Error_Detected;
13962 Lo := Build_Scalar_Bound
13963 (Type_Low_Bound (Derived_Type),
13964 Parent_Type, Implicit_Base);
13966 Hi := Build_Scalar_Bound
13967 (Type_High_Bound (Derived_Type),
13968 Parent_Type, Implicit_Base);
13975 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13977 Set_Parent (Rng, N);
13978 Set_Scalar_Range (Derived_Type, Rng);
13980 -- Analyze the bounds
13982 Analyze_And_Resolve (Lo, Implicit_Base);
13983 Analyze_And_Resolve (Hi, Implicit_Base);
13985 -- Analyze the range itself, except that we do not analyze it if
13986 -- the bounds are real literals, and we have a fixed-point type.
13987 -- The reason for this is that we delay setting the bounds in this
13988 -- case till we know the final Small and Size values (see circuit
13989 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13991 if Is_Fixed_Point_Type (Parent_Type)
13992 and then Nkind (Lo) = N_Real_Literal
13993 and then Nkind (Hi) = N_Real_Literal
13997 -- Here we do the analysis of the range
13999 -- Note: we do this manually, since if we do a normal Analyze and
14000 -- Resolve call, there are problems with the conversions used for
14001 -- the derived type range.
14004 Set_Etype (Rng, Implicit_Base);
14005 Set_Analyzed (Rng, True);
14007 end Convert_Scalar_Bounds;
14009 -------------------
14010 -- Copy_And_Swap --
14011 -------------------
14013 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
14015 -- Initialize new full declaration entity by copying the pertinent
14016 -- fields of the corresponding private declaration entity.
14018 -- We temporarily set Ekind to a value appropriate for a type to
14019 -- avoid assert failures in Einfo from checking for setting type
14020 -- attributes on something that is not a type. Ekind (Priv) is an
14021 -- appropriate choice, since it allowed the attributes to be set
14022 -- in the first place. This Ekind value will be modified later.
14024 Set_Ekind (Full, Ekind (Priv));
14026 -- Also set Etype temporarily to Any_Type, again, in the absence
14027 -- of errors, it will be properly reset, and if there are errors,
14028 -- then we want a value of Any_Type to remain.
14030 Set_Etype (Full, Any_Type);
14032 -- Now start copying attributes
14034 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
14036 if Has_Discriminants (Full) then
14037 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
14038 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
14041 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
14042 Set_Homonym (Full, Homonym (Priv));
14043 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
14044 Set_Is_Public (Full, Is_Public (Priv));
14045 Set_Is_Pure (Full, Is_Pure (Priv));
14046 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
14047 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
14048 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
14049 Set_Has_Pragma_Unreferenced_Objects
14050 (Full, Has_Pragma_Unreferenced_Objects
14053 Conditional_Delay (Full, Priv);
14055 if Is_Tagged_Type (Full) then
14056 Set_Direct_Primitive_Operations
14057 (Full, Direct_Primitive_Operations (Priv));
14058 Set_No_Tagged_Streams_Pragma
14059 (Full, No_Tagged_Streams_Pragma (Priv));
14061 if Is_Base_Type (Priv) then
14062 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
14066 Set_Is_Volatile (Full, Is_Volatile (Priv));
14067 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
14068 Set_Scope (Full, Scope (Priv));
14069 Set_Next_Entity (Full, Next_Entity (Priv));
14070 Set_First_Entity (Full, First_Entity (Priv));
14071 Set_Last_Entity (Full, Last_Entity (Priv));
14073 -- If access types have been recorded for later handling, keep them in
14074 -- the full view so that they get handled when the full view freeze
14075 -- node is expanded.
14077 if Present (Freeze_Node (Priv))
14078 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
14080 Ensure_Freeze_Node (Full);
14081 Set_Access_Types_To_Process
14082 (Freeze_Node (Full),
14083 Access_Types_To_Process (Freeze_Node (Priv)));
14086 -- Swap the two entities. Now Private is the full type entity and Full
14087 -- is the private one. They will be swapped back at the end of the
14088 -- private part. This swapping ensures that the entity that is visible
14089 -- in the private part is the full declaration.
14091 Exchange_Entities (Priv, Full);
14092 Append_Entity (Full, Scope (Full));
14095 -------------------------------------
14096 -- Copy_Array_Base_Type_Attributes --
14097 -------------------------------------
14099 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
14101 Set_Component_Alignment (T1, Component_Alignment (T2));
14102 Set_Component_Type (T1, Component_Type (T2));
14103 Set_Component_Size (T1, Component_Size (T2));
14104 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
14105 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
14106 Propagate_Concurrent_Flags (T1, T2);
14107 Set_Is_Packed (T1, Is_Packed (T2));
14108 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
14109 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
14110 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
14111 end Copy_Array_Base_Type_Attributes;
14113 -----------------------------------
14114 -- Copy_Array_Subtype_Attributes --
14115 -----------------------------------
14117 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
14119 Set_Size_Info (T1, T2);
14121 Set_First_Index (T1, First_Index (T2));
14122 Set_Is_Aliased (T1, Is_Aliased (T2));
14123 Set_Is_Volatile (T1, Is_Volatile (T2));
14124 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
14125 Set_Is_Constrained (T1, Is_Constrained (T2));
14126 Set_Depends_On_Private (T1, Has_Private_Component (T2));
14127 Inherit_Rep_Item_Chain (T1, T2);
14128 Set_Convention (T1, Convention (T2));
14129 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
14130 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
14131 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
14132 end Copy_Array_Subtype_Attributes;
14134 -----------------------------------
14135 -- Create_Constrained_Components --
14136 -----------------------------------
14138 procedure Create_Constrained_Components
14140 Decl_Node : Node_Id;
14142 Constraints : Elist_Id)
14144 Loc : constant Source_Ptr := Sloc (Subt);
14145 Comp_List : constant Elist_Id := New_Elmt_List;
14146 Parent_Type : constant Entity_Id := Etype (Typ);
14147 Assoc_List : constant List_Id := New_List;
14148 Discr_Val : Elmt_Id;
14152 Is_Static : Boolean := True;
14154 procedure Collect_Fixed_Components (Typ : Entity_Id);
14155 -- Collect parent type components that do not appear in a variant part
14157 procedure Create_All_Components;
14158 -- Iterate over Comp_List to create the components of the subtype
14160 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
14161 -- Creates a new component from Old_Compon, copying all the fields from
14162 -- it, including its Etype, inserts the new component in the Subt entity
14163 -- chain and returns the new component.
14165 function Is_Variant_Record (T : Entity_Id) return Boolean;
14166 -- If true, and discriminants are static, collect only components from
14167 -- variants selected by discriminant values.
14169 ------------------------------
14170 -- Collect_Fixed_Components --
14171 ------------------------------
14173 procedure Collect_Fixed_Components (Typ : Entity_Id) is
14175 -- Build association list for discriminants, and find components of the
14176 -- variant part selected by the values of the discriminants.
14178 Old_C := First_Discriminant (Typ);
14179 Discr_Val := First_Elmt (Constraints);
14180 while Present (Old_C) loop
14181 Append_To (Assoc_List,
14182 Make_Component_Association (Loc,
14183 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
14184 Expression => New_Copy (Node (Discr_Val))));
14186 Next_Elmt (Discr_Val);
14187 Next_Discriminant (Old_C);
14190 -- The tag and the possible parent component are unconditionally in
14193 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
14194 Old_C := First_Component (Typ);
14195 while Present (Old_C) loop
14196 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
14197 Append_Elmt (Old_C, Comp_List);
14200 Next_Component (Old_C);
14203 end Collect_Fixed_Components;
14205 ---------------------------
14206 -- Create_All_Components --
14207 ---------------------------
14209 procedure Create_All_Components is
14213 Comp := First_Elmt (Comp_List);
14214 while Present (Comp) loop
14215 Old_C := Node (Comp);
14216 New_C := Create_Component (Old_C);
14220 Constrain_Component_Type
14221 (Old_C, Subt, Decl_Node, Typ, Constraints));
14222 Set_Is_Public (New_C, Is_Public (Subt));
14226 end Create_All_Components;
14228 ----------------------
14229 -- Create_Component --
14230 ----------------------
14232 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
14233 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
14236 if Ekind (Old_Compon) = E_Discriminant
14237 and then Is_Completely_Hidden (Old_Compon)
14239 -- This is a shadow discriminant created for a discriminant of
14240 -- the parent type, which needs to be present in the subtype.
14241 -- Give the shadow discriminant an internal name that cannot
14242 -- conflict with that of visible components.
14244 Set_Chars (New_Compon, New_Internal_Name ('C'));
14247 -- Set the parent so we have a proper link for freezing etc. This is
14248 -- not a real parent pointer, since of course our parent does not own
14249 -- up to us and reference us, we are an illegitimate child of the
14250 -- original parent.
14252 Set_Parent (New_Compon, Parent (Old_Compon));
14254 -- If the old component's Esize was already determined and is a
14255 -- static value, then the new component simply inherits it. Otherwise
14256 -- the old component's size may require run-time determination, but
14257 -- the new component's size still might be statically determinable
14258 -- (if, for example it has a static constraint). In that case we want
14259 -- Layout_Type to recompute the component's size, so we reset its
14260 -- size and positional fields.
14262 if Frontend_Layout_On_Target
14263 and then not Known_Static_Esize (Old_Compon)
14265 Set_Esize (New_Compon, Uint_0);
14266 Init_Normalized_First_Bit (New_Compon);
14267 Init_Normalized_Position (New_Compon);
14268 Init_Normalized_Position_Max (New_Compon);
14271 -- We do not want this node marked as Comes_From_Source, since
14272 -- otherwise it would get first class status and a separate cross-
14273 -- reference line would be generated. Illegitimate children do not
14274 -- rate such recognition.
14276 Set_Comes_From_Source (New_Compon, False);
14278 -- But it is a real entity, and a birth certificate must be properly
14279 -- registered by entering it into the entity list.
14281 Enter_Name (New_Compon);
14284 end Create_Component;
14286 -----------------------
14287 -- Is_Variant_Record --
14288 -----------------------
14290 function Is_Variant_Record (T : Entity_Id) return Boolean is
14292 return Nkind (Parent (T)) = N_Full_Type_Declaration
14293 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
14294 and then Present (Component_List (Type_Definition (Parent (T))))
14297 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
14298 end Is_Variant_Record;
14300 -- Start of processing for Create_Constrained_Components
14303 pragma Assert (Subt /= Base_Type (Subt));
14304 pragma Assert (Typ = Base_Type (Typ));
14306 Set_First_Entity (Subt, Empty);
14307 Set_Last_Entity (Subt, Empty);
14309 -- Check whether constraint is fully static, in which case we can
14310 -- optimize the list of components.
14312 Discr_Val := First_Elmt (Constraints);
14313 while Present (Discr_Val) loop
14314 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14315 Is_Static := False;
14319 Next_Elmt (Discr_Val);
14322 Set_Has_Static_Discriminants (Subt, Is_Static);
14326 -- Inherit the discriminants of the parent type
14328 Add_Discriminants : declare
14334 Old_C := First_Discriminant (Typ);
14336 while Present (Old_C) loop
14337 Num_Disc := Num_Disc + 1;
14338 New_C := Create_Component (Old_C);
14339 Set_Is_Public (New_C, Is_Public (Subt));
14340 Next_Discriminant (Old_C);
14343 -- For an untagged derived subtype, the number of discriminants may
14344 -- be smaller than the number of inherited discriminants, because
14345 -- several of them may be renamed by a single new discriminant or
14346 -- constrained. In this case, add the hidden discriminants back into
14347 -- the subtype, because they need to be present if the optimizer of
14348 -- the GCC 4.x back-end decides to break apart assignments between
14349 -- objects using the parent view into member-wise assignments.
14353 if Is_Derived_Type (Typ)
14354 and then not Is_Tagged_Type (Typ)
14356 Old_C := First_Stored_Discriminant (Typ);
14358 while Present (Old_C) loop
14359 Num_Gird := Num_Gird + 1;
14360 Next_Stored_Discriminant (Old_C);
14364 if Num_Gird > Num_Disc then
14366 -- Find out multiple uses of new discriminants, and add hidden
14367 -- components for the extra renamed discriminants. We recognize
14368 -- multiple uses through the Corresponding_Discriminant of a
14369 -- new discriminant: if it constrains several old discriminants,
14370 -- this field points to the last one in the parent type. The
14371 -- stored discriminants of the derived type have the same name
14372 -- as those of the parent.
14376 New_Discr : Entity_Id;
14377 Old_Discr : Entity_Id;
14380 Constr := First_Elmt (Stored_Constraint (Typ));
14381 Old_Discr := First_Stored_Discriminant (Typ);
14382 while Present (Constr) loop
14383 if Is_Entity_Name (Node (Constr))
14384 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14386 New_Discr := Entity (Node (Constr));
14388 if Chars (Corresponding_Discriminant (New_Discr)) /=
14391 -- The new discriminant has been used to rename a
14392 -- subsequent old discriminant. Introduce a shadow
14393 -- component for the current old discriminant.
14395 New_C := Create_Component (Old_Discr);
14396 Set_Original_Record_Component (New_C, Old_Discr);
14400 -- The constraint has eliminated the old discriminant.
14401 -- Introduce a shadow component.
14403 New_C := Create_Component (Old_Discr);
14404 Set_Original_Record_Component (New_C, Old_Discr);
14407 Next_Elmt (Constr);
14408 Next_Stored_Discriminant (Old_Discr);
14412 end Add_Discriminants;
14415 and then Is_Variant_Record (Typ)
14417 Collect_Fixed_Components (Typ);
14419 Gather_Components (
14421 Component_List (Type_Definition (Parent (Typ))),
14422 Governed_By => Assoc_List,
14424 Report_Errors => Errors);
14425 pragma Assert (not Errors
14426 or else Serious_Errors_Detected > 0);
14428 Create_All_Components;
14430 -- If the subtype declaration is created for a tagged type derivation
14431 -- with constraints, we retrieve the record definition of the parent
14432 -- type to select the components of the proper variant.
14435 and then Is_Tagged_Type (Typ)
14436 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14438 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14439 and then Is_Variant_Record (Parent_Type)
14441 Collect_Fixed_Components (Typ);
14445 Component_List (Type_Definition (Parent (Parent_Type))),
14446 Governed_By => Assoc_List,
14448 Report_Errors => Errors);
14450 -- Note: previously there was a check at this point that no errors
14451 -- were detected. As a consequence of AI05-220 there may be an error
14452 -- if an inherited discriminant that controls a variant has a non-
14453 -- static constraint.
14455 -- If the tagged derivation has a type extension, collect all the
14456 -- new components therein.
14458 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14460 Old_C := First_Component (Typ);
14461 while Present (Old_C) loop
14462 if Original_Record_Component (Old_C) = Old_C
14463 and then Chars (Old_C) /= Name_uTag
14464 and then Chars (Old_C) /= Name_uParent
14466 Append_Elmt (Old_C, Comp_List);
14469 Next_Component (Old_C);
14473 Create_All_Components;
14476 -- If discriminants are not static, or if this is a multi-level type
14477 -- extension, we have to include all components of the parent type.
14479 Old_C := First_Component (Typ);
14480 while Present (Old_C) loop
14481 New_C := Create_Component (Old_C);
14485 Constrain_Component_Type
14486 (Old_C, Subt, Decl_Node, Typ, Constraints));
14487 Set_Is_Public (New_C, Is_Public (Subt));
14489 Next_Component (Old_C);
14494 end Create_Constrained_Components;
14496 ------------------------------------------
14497 -- Decimal_Fixed_Point_Type_Declaration --
14498 ------------------------------------------
14500 procedure Decimal_Fixed_Point_Type_Declaration
14504 Loc : constant Source_Ptr := Sloc (Def);
14505 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14506 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14507 Implicit_Base : Entity_Id;
14514 Check_SPARK_05_Restriction
14515 ("decimal fixed point type is not allowed", Def);
14516 Check_Restriction (No_Fixed_Point, Def);
14518 -- Create implicit base type
14521 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14522 Set_Etype (Implicit_Base, Implicit_Base);
14524 -- Analyze and process delta expression
14526 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14528 Check_Delta_Expression (Delta_Expr);
14529 Delta_Val := Expr_Value_R (Delta_Expr);
14531 -- Check delta is power of 10, and determine scale value from it
14537 Scale_Val := Uint_0;
14540 if Val < Ureal_1 then
14541 while Val < Ureal_1 loop
14542 Val := Val * Ureal_10;
14543 Scale_Val := Scale_Val + 1;
14546 if Scale_Val > 18 then
14547 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14548 Scale_Val := UI_From_Int (+18);
14552 while Val > Ureal_1 loop
14553 Val := Val / Ureal_10;
14554 Scale_Val := Scale_Val - 1;
14557 if Scale_Val < -18 then
14558 Error_Msg_N ("scale is less than minimum value of -18", Def);
14559 Scale_Val := UI_From_Int (-18);
14563 if Val /= Ureal_1 then
14564 Error_Msg_N ("delta expression must be a power of 10", Def);
14565 Delta_Val := Ureal_10 ** (-Scale_Val);
14569 -- Set delta, scale and small (small = delta for decimal type)
14571 Set_Delta_Value (Implicit_Base, Delta_Val);
14572 Set_Scale_Value (Implicit_Base, Scale_Val);
14573 Set_Small_Value (Implicit_Base, Delta_Val);
14575 -- Analyze and process digits expression
14577 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14578 Check_Digits_Expression (Digs_Expr);
14579 Digs_Val := Expr_Value (Digs_Expr);
14581 if Digs_Val > 18 then
14582 Digs_Val := UI_From_Int (+18);
14583 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14586 Set_Digits_Value (Implicit_Base, Digs_Val);
14587 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14589 -- Set range of base type from digits value for now. This will be
14590 -- expanded to represent the true underlying base range by Freeze.
14592 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14594 -- Note: We leave size as zero for now, size will be set at freeze
14595 -- time. We have to do this for ordinary fixed-point, because the size
14596 -- depends on the specified small, and we might as well do the same for
14597 -- decimal fixed-point.
14599 pragma Assert (Esize (Implicit_Base) = Uint_0);
14601 -- If there are bounds given in the declaration use them as the
14602 -- bounds of the first named subtype.
14604 if Present (Real_Range_Specification (Def)) then
14606 RRS : constant Node_Id := Real_Range_Specification (Def);
14607 Low : constant Node_Id := Low_Bound (RRS);
14608 High : constant Node_Id := High_Bound (RRS);
14613 Analyze_And_Resolve (Low, Any_Real);
14614 Analyze_And_Resolve (High, Any_Real);
14615 Check_Real_Bound (Low);
14616 Check_Real_Bound (High);
14617 Low_Val := Expr_Value_R (Low);
14618 High_Val := Expr_Value_R (High);
14620 if Low_Val < (-Bound_Val) then
14622 ("range low bound too small for digits value", Low);
14623 Low_Val := -Bound_Val;
14626 if High_Val > Bound_Val then
14628 ("range high bound too large for digits value", High);
14629 High_Val := Bound_Val;
14632 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14635 -- If no explicit range, use range that corresponds to given
14636 -- digits value. This will end up as the final range for the
14640 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14643 -- Complete entity for first subtype. The inheritance of the rep item
14644 -- chain ensures that SPARK-related pragmas are not clobbered when the
14645 -- decimal fixed point type acts as a full view of a private type.
14647 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14648 Set_Etype (T, Implicit_Base);
14649 Set_Size_Info (T, Implicit_Base);
14650 Inherit_Rep_Item_Chain (T, Implicit_Base);
14651 Set_Digits_Value (T, Digs_Val);
14652 Set_Delta_Value (T, Delta_Val);
14653 Set_Small_Value (T, Delta_Val);
14654 Set_Scale_Value (T, Scale_Val);
14655 Set_Is_Constrained (T);
14656 end Decimal_Fixed_Point_Type_Declaration;
14658 -----------------------------------
14659 -- Derive_Progenitor_Subprograms --
14660 -----------------------------------
14662 procedure Derive_Progenitor_Subprograms
14663 (Parent_Type : Entity_Id;
14664 Tagged_Type : Entity_Id)
14669 Iface_Elmt : Elmt_Id;
14670 Iface_Subp : Entity_Id;
14671 New_Subp : Entity_Id := Empty;
14672 Prim_Elmt : Elmt_Id;
14677 pragma Assert (Ada_Version >= Ada_2005
14678 and then Is_Record_Type (Tagged_Type)
14679 and then Is_Tagged_Type (Tagged_Type)
14680 and then Has_Interfaces (Tagged_Type));
14682 -- Step 1: Transfer to the full-view primitives associated with the
14683 -- partial-view that cover interface primitives. Conceptually this
14684 -- work should be done later by Process_Full_View; done here to
14685 -- simplify its implementation at later stages. It can be safely
14686 -- done here because interfaces must be visible in the partial and
14687 -- private view (RM 7.3(7.3/2)).
14689 -- Small optimization: This work is only required if the parent may
14690 -- have entities whose Alias attribute reference an interface primitive.
14691 -- Such a situation may occur if the parent is an abstract type and the
14692 -- primitive has not been yet overridden or if the parent is a generic
14693 -- formal type covering interfaces.
14695 -- If the tagged type is not abstract, it cannot have abstract
14696 -- primitives (the only entities in the list of primitives of
14697 -- non-abstract tagged types that can reference abstract primitives
14698 -- through its Alias attribute are the internal entities that have
14699 -- attribute Interface_Alias, and these entities are generated later
14700 -- by Add_Internal_Interface_Entities).
14702 if In_Private_Part (Current_Scope)
14703 and then (Is_Abstract_Type (Parent_Type)
14705 Is_Generic_Type (Parent_Type))
14707 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14708 while Present (Elmt) loop
14709 Subp := Node (Elmt);
14711 -- At this stage it is not possible to have entities in the list
14712 -- of primitives that have attribute Interface_Alias.
14714 pragma Assert (No (Interface_Alias (Subp)));
14716 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14718 if Is_Interface (Typ) then
14719 E := Find_Primitive_Covering_Interface
14720 (Tagged_Type => Tagged_Type,
14721 Iface_Prim => Subp);
14724 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14726 Replace_Elmt (Elmt, E);
14727 Remove_Homonym (Subp);
14735 -- Step 2: Add primitives of progenitors that are not implemented by
14736 -- parents of Tagged_Type.
14738 if Present (Interfaces (Base_Type (Tagged_Type))) then
14739 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14740 while Present (Iface_Elmt) loop
14741 Iface := Node (Iface_Elmt);
14743 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14744 while Present (Prim_Elmt) loop
14745 Iface_Subp := Node (Prim_Elmt);
14747 -- Exclude derivation of predefined primitives except those
14748 -- that come from source, or are inherited from one that comes
14749 -- from source. Required to catch declarations of equality
14750 -- operators of interfaces. For example:
14752 -- type Iface is interface;
14753 -- function "=" (Left, Right : Iface) return Boolean;
14755 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14756 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14758 E := Find_Primitive_Covering_Interface
14759 (Tagged_Type => Tagged_Type,
14760 Iface_Prim => Iface_Subp);
14762 -- If not found we derive a new primitive leaving its alias
14763 -- attribute referencing the interface primitive.
14767 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14769 -- Ada 2012 (AI05-0197): If the covering primitive's name
14770 -- differs from the name of the interface primitive then it
14771 -- is a private primitive inherited from a parent type. In
14772 -- such case, given that Tagged_Type covers the interface,
14773 -- the inherited private primitive becomes visible. For such
14774 -- purpose we add a new entity that renames the inherited
14775 -- private primitive.
14777 elsif Chars (E) /= Chars (Iface_Subp) then
14778 pragma Assert (Has_Suffix (E, 'P'));
14780 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14781 Set_Alias (New_Subp, E);
14782 Set_Is_Abstract_Subprogram (New_Subp,
14783 Is_Abstract_Subprogram (E));
14785 -- Propagate to the full view interface entities associated
14786 -- with the partial view.
14788 elsif In_Private_Part (Current_Scope)
14789 and then Present (Alias (E))
14790 and then Alias (E) = Iface_Subp
14792 List_Containing (Parent (E)) /=
14793 Private_Declarations
14795 (Unit_Declaration_Node (Current_Scope)))
14797 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14801 Next_Elmt (Prim_Elmt);
14804 Next_Elmt (Iface_Elmt);
14807 end Derive_Progenitor_Subprograms;
14809 -----------------------
14810 -- Derive_Subprogram --
14811 -----------------------
14813 procedure Derive_Subprogram
14814 (New_Subp : out Entity_Id;
14815 Parent_Subp : Entity_Id;
14816 Derived_Type : Entity_Id;
14817 Parent_Type : Entity_Id;
14818 Actual_Subp : Entity_Id := Empty)
14820 Formal : Entity_Id;
14821 -- Formal parameter of parent primitive operation
14823 Formal_Of_Actual : Entity_Id;
14824 -- Formal parameter of actual operation, when the derivation is to
14825 -- create a renaming for a primitive operation of an actual in an
14828 New_Formal : Entity_Id;
14829 -- Formal of inherited operation
14831 Visible_Subp : Entity_Id := Parent_Subp;
14833 function Is_Private_Overriding return Boolean;
14834 -- If Subp is a private overriding of a visible operation, the inherited
14835 -- operation derives from the overridden op (even though its body is the
14836 -- overriding one) and the inherited operation is visible now. See
14837 -- sem_disp to see the full details of the handling of the overridden
14838 -- subprogram, which is removed from the list of primitive operations of
14839 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14840 -- and used to diagnose abstract operations that need overriding in the
14843 procedure Replace_Type (Id, New_Id : Entity_Id);
14844 -- When the type is an anonymous access type, create a new access type
14845 -- designating the derived type.
14847 procedure Set_Derived_Name;
14848 -- This procedure sets the appropriate Chars name for New_Subp. This
14849 -- is normally just a copy of the parent name. An exception arises for
14850 -- type support subprograms, where the name is changed to reflect the
14851 -- name of the derived type, e.g. if type foo is derived from type bar,
14852 -- then a procedure barDA is derived with a name fooDA.
14854 ---------------------------
14855 -- Is_Private_Overriding --
14856 ---------------------------
14858 function Is_Private_Overriding return Boolean is
14862 -- If the parent is not a dispatching operation there is no
14863 -- need to investigate overridings
14865 if not Is_Dispatching_Operation (Parent_Subp) then
14869 -- The visible operation that is overridden is a homonym of the
14870 -- parent subprogram. We scan the homonym chain to find the one
14871 -- whose alias is the subprogram we are deriving.
14873 Prev := Current_Entity (Parent_Subp);
14874 while Present (Prev) loop
14875 if Ekind (Prev) = Ekind (Parent_Subp)
14876 and then Alias (Prev) = Parent_Subp
14877 and then Scope (Parent_Subp) = Scope (Prev)
14878 and then not Is_Hidden (Prev)
14880 Visible_Subp := Prev;
14884 Prev := Homonym (Prev);
14888 end Is_Private_Overriding;
14894 procedure Replace_Type (Id, New_Id : Entity_Id) is
14895 Id_Type : constant Entity_Id := Etype (Id);
14896 Acc_Type : Entity_Id;
14897 Par : constant Node_Id := Parent (Derived_Type);
14900 -- When the type is an anonymous access type, create a new access
14901 -- type designating the derived type. This itype must be elaborated
14902 -- at the point of the derivation, not on subsequent calls that may
14903 -- be out of the proper scope for Gigi, so we insert a reference to
14904 -- it after the derivation.
14906 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14908 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14911 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14912 and then Present (Full_View (Desig_Typ))
14913 and then not Is_Private_Type (Parent_Type)
14915 Desig_Typ := Full_View (Desig_Typ);
14918 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14920 -- Ada 2005 (AI-251): Handle also derivations of abstract
14921 -- interface primitives.
14923 or else (Is_Interface (Desig_Typ)
14924 and then not Is_Class_Wide_Type (Desig_Typ))
14926 Acc_Type := New_Copy (Id_Type);
14927 Set_Etype (Acc_Type, Acc_Type);
14928 Set_Scope (Acc_Type, New_Subp);
14930 -- Set size of anonymous access type. If we have an access
14931 -- to an unconstrained array, this is a fat pointer, so it
14932 -- is sizes at twice addtress size.
14934 if Is_Array_Type (Desig_Typ)
14935 and then not Is_Constrained (Desig_Typ)
14937 Init_Size (Acc_Type, 2 * System_Address_Size);
14939 -- Other cases use a thin pointer
14942 Init_Size (Acc_Type, System_Address_Size);
14945 -- Set remaining characterstics of anonymous access type
14947 Init_Alignment (Acc_Type);
14948 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14950 Set_Etype (New_Id, Acc_Type);
14951 Set_Scope (New_Id, New_Subp);
14953 -- Create a reference to it
14955 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14958 Set_Etype (New_Id, Id_Type);
14962 -- In Ada2012, a formal may have an incomplete type but the type
14963 -- derivation that inherits the primitive follows the full view.
14965 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14967 (Ekind (Id_Type) = E_Record_Type_With_Private
14968 and then Present (Full_View (Id_Type))
14970 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14972 (Ada_Version >= Ada_2012
14973 and then Ekind (Id_Type) = E_Incomplete_Type
14974 and then Full_View (Id_Type) = Parent_Type)
14976 -- Constraint checks on formals are generated during expansion,
14977 -- based on the signature of the original subprogram. The bounds
14978 -- of the derived type are not relevant, and thus we can use
14979 -- the base type for the formals. However, the return type may be
14980 -- used in a context that requires that the proper static bounds
14981 -- be used (a case statement, for example) and for those cases
14982 -- we must use the derived type (first subtype), not its base.
14984 -- If the derived_type_definition has no constraints, we know that
14985 -- the derived type has the same constraints as the first subtype
14986 -- of the parent, and we can also use it rather than its base,
14987 -- which can lead to more efficient code.
14989 if Etype (Id) = Parent_Type then
14990 if Is_Scalar_Type (Parent_Type)
14992 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14994 Set_Etype (New_Id, Derived_Type);
14996 elsif Nkind (Par) = N_Full_Type_Declaration
14998 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
15001 (Subtype_Indication (Type_Definition (Par)))
15003 Set_Etype (New_Id, Derived_Type);
15006 Set_Etype (New_Id, Base_Type (Derived_Type));
15010 Set_Etype (New_Id, Base_Type (Derived_Type));
15014 Set_Etype (New_Id, Etype (Id));
15018 ----------------------
15019 -- Set_Derived_Name --
15020 ----------------------
15022 procedure Set_Derived_Name is
15023 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
15025 if Nm = TSS_Null then
15026 Set_Chars (New_Subp, Chars (Parent_Subp));
15028 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
15030 end Set_Derived_Name;
15032 -- Start of processing for Derive_Subprogram
15035 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
15036 Set_Ekind (New_Subp, Ekind (Parent_Subp));
15038 -- Check whether the inherited subprogram is a private operation that
15039 -- should be inherited but not yet made visible. Such subprograms can
15040 -- become visible at a later point (e.g., the private part of a public
15041 -- child unit) via Declare_Inherited_Private_Subprograms. If the
15042 -- following predicate is true, then this is not such a private
15043 -- operation and the subprogram simply inherits the name of the parent
15044 -- subprogram. Note the special check for the names of controlled
15045 -- operations, which are currently exempted from being inherited with
15046 -- a hidden name because they must be findable for generation of
15047 -- implicit run-time calls.
15049 if not Is_Hidden (Parent_Subp)
15050 or else Is_Internal (Parent_Subp)
15051 or else Is_Private_Overriding
15052 or else Is_Internal_Name (Chars (Parent_Subp))
15053 or else (Is_Controlled (Parent_Type)
15054 and then Nam_In (Chars (Parent_Subp), Name_Adjust,
15060 -- An inherited dispatching equality will be overridden by an internally
15061 -- generated one, or by an explicit one, so preserve its name and thus
15062 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
15063 -- private operation it may become invisible if the full view has
15064 -- progenitors, and the dispatch table will be malformed.
15065 -- We check that the type is limited to handle the anomalous declaration
15066 -- of Limited_Controlled, which is derived from a non-limited type, and
15067 -- which is handled specially elsewhere as well.
15069 elsif Chars (Parent_Subp) = Name_Op_Eq
15070 and then Is_Dispatching_Operation (Parent_Subp)
15071 and then Etype (Parent_Subp) = Standard_Boolean
15072 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
15074 Etype (First_Formal (Parent_Subp)) =
15075 Etype (Next_Formal (First_Formal (Parent_Subp)))
15079 -- If parent is hidden, this can be a regular derivation if the
15080 -- parent is immediately visible in a non-instantiating context,
15081 -- or if we are in the private part of an instance. This test
15082 -- should still be refined ???
15084 -- The test for In_Instance_Not_Visible avoids inheriting the derived
15085 -- operation as a non-visible operation in cases where the parent
15086 -- subprogram might not be visible now, but was visible within the
15087 -- original generic, so it would be wrong to make the inherited
15088 -- subprogram non-visible now. (Not clear if this test is fully
15089 -- correct; are there any cases where we should declare the inherited
15090 -- operation as not visible to avoid it being overridden, e.g., when
15091 -- the parent type is a generic actual with private primitives ???)
15093 -- (they should be treated the same as other private inherited
15094 -- subprograms, but it's not clear how to do this cleanly). ???
15096 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15097 and then Is_Immediately_Visible (Parent_Subp)
15098 and then not In_Instance)
15099 or else In_Instance_Not_Visible
15103 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
15104 -- overrides an interface primitive because interface primitives
15105 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
15107 elsif Ada_Version >= Ada_2005
15108 and then Is_Dispatching_Operation (Parent_Subp)
15109 and then Present (Covered_Interface_Op (Parent_Subp))
15113 -- Otherwise, the type is inheriting a private operation, so enter it
15114 -- with a special name so it can't be overridden.
15117 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
15120 Set_Parent (New_Subp, Parent (Derived_Type));
15122 if Present (Actual_Subp) then
15123 Replace_Type (Actual_Subp, New_Subp);
15125 Replace_Type (Parent_Subp, New_Subp);
15128 Conditional_Delay (New_Subp, Parent_Subp);
15130 -- If we are creating a renaming for a primitive operation of an
15131 -- actual of a generic derived type, we must examine the signature
15132 -- of the actual primitive, not that of the generic formal, which for
15133 -- example may be an interface. However the name and initial value
15134 -- of the inherited operation are those of the formal primitive.
15136 Formal := First_Formal (Parent_Subp);
15138 if Present (Actual_Subp) then
15139 Formal_Of_Actual := First_Formal (Actual_Subp);
15141 Formal_Of_Actual := Empty;
15144 while Present (Formal) loop
15145 New_Formal := New_Copy (Formal);
15147 -- Normally we do not go copying parents, but in the case of
15148 -- formals, we need to link up to the declaration (which is the
15149 -- parameter specification), and it is fine to link up to the
15150 -- original formal's parameter specification in this case.
15152 Set_Parent (New_Formal, Parent (Formal));
15153 Append_Entity (New_Formal, New_Subp);
15155 if Present (Formal_Of_Actual) then
15156 Replace_Type (Formal_Of_Actual, New_Formal);
15157 Next_Formal (Formal_Of_Actual);
15159 Replace_Type (Formal, New_Formal);
15162 Next_Formal (Formal);
15165 -- If this derivation corresponds to a tagged generic actual, then
15166 -- primitive operations rename those of the actual. Otherwise the
15167 -- primitive operations rename those of the parent type, If the parent
15168 -- renames an intrinsic operator, so does the new subprogram. We except
15169 -- concatenation, which is always properly typed, and does not get
15170 -- expanded as other intrinsic operations.
15172 if No (Actual_Subp) then
15173 if Is_Intrinsic_Subprogram (Parent_Subp) then
15174 Set_Is_Intrinsic_Subprogram (New_Subp);
15176 if Present (Alias (Parent_Subp))
15177 and then Chars (Parent_Subp) /= Name_Op_Concat
15179 Set_Alias (New_Subp, Alias (Parent_Subp));
15181 Set_Alias (New_Subp, Parent_Subp);
15185 Set_Alias (New_Subp, Parent_Subp);
15189 Set_Alias (New_Subp, Actual_Subp);
15192 -- Derived subprograms of a tagged type must inherit the convention
15193 -- of the parent subprogram (a requirement of AI-117). Derived
15194 -- subprograms of untagged types simply get convention Ada by default.
15196 -- If the derived type is a tagged generic formal type with unknown
15197 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
15199 -- However, if the type is derived from a generic formal, the further
15200 -- inherited subprogram has the convention of the non-generic ancestor.
15201 -- Otherwise there would be no way to override the operation.
15202 -- (This is subject to forthcoming ARG discussions).
15204 if Is_Tagged_Type (Derived_Type) then
15205 if Is_Generic_Type (Derived_Type)
15206 and then Has_Unknown_Discriminants (Derived_Type)
15208 Set_Convention (New_Subp, Convention_Intrinsic);
15211 if Is_Generic_Type (Parent_Type)
15212 and then Has_Unknown_Discriminants (Parent_Type)
15214 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
15216 Set_Convention (New_Subp, Convention (Parent_Subp));
15221 -- Predefined controlled operations retain their name even if the parent
15222 -- is hidden (see above), but they are not primitive operations if the
15223 -- ancestor is not visible, for example if the parent is a private
15224 -- extension completed with a controlled extension. Note that a full
15225 -- type that is controlled can break privacy: the flag Is_Controlled is
15226 -- set on both views of the type.
15228 if Is_Controlled (Parent_Type)
15229 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
15232 and then Is_Hidden (Parent_Subp)
15233 and then not Is_Visibly_Controlled (Parent_Type)
15235 Set_Is_Hidden (New_Subp);
15238 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
15239 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
15241 if Ekind (Parent_Subp) = E_Procedure then
15242 Set_Is_Valued_Procedure
15243 (New_Subp, Is_Valued_Procedure (Parent_Subp));
15245 Set_Has_Controlling_Result
15246 (New_Subp, Has_Controlling_Result (Parent_Subp));
15249 -- No_Return must be inherited properly. If this is overridden in the
15250 -- case of a dispatching operation, then a check is made in Sem_Disp
15251 -- that the overriding operation is also No_Return (no such check is
15252 -- required for the case of non-dispatching operation.
15254 Set_No_Return (New_Subp, No_Return (Parent_Subp));
15256 -- A derived function with a controlling result is abstract. If the
15257 -- Derived_Type is a nonabstract formal generic derived type, then
15258 -- inherited operations are not abstract: the required check is done at
15259 -- instantiation time. If the derivation is for a generic actual, the
15260 -- function is not abstract unless the actual is.
15262 if Is_Generic_Type (Derived_Type)
15263 and then not Is_Abstract_Type (Derived_Type)
15267 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
15268 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
15270 -- A subprogram subject to pragma Extensions_Visible with value False
15271 -- requires overriding if the subprogram has at least one controlling
15272 -- OUT parameter (SPARK RM 6.1.7(6)).
15274 elsif Ada_Version >= Ada_2005
15275 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15276 or else (Is_Tagged_Type (Derived_Type)
15277 and then Etype (New_Subp) = Derived_Type
15278 and then not Is_Null_Extension (Derived_Type))
15279 or else (Is_Tagged_Type (Derived_Type)
15280 and then Ekind (Etype (New_Subp)) =
15281 E_Anonymous_Access_Type
15282 and then Designated_Type (Etype (New_Subp)) =
15284 and then not Is_Null_Extension (Derived_Type))
15285 or else (Comes_From_Source (Alias (New_Subp))
15286 and then Is_EVF_Procedure (Alias (New_Subp))))
15287 and then No (Actual_Subp)
15289 if not Is_Tagged_Type (Derived_Type)
15290 or else Is_Abstract_Type (Derived_Type)
15291 or else Is_Abstract_Subprogram (Alias (New_Subp))
15293 Set_Is_Abstract_Subprogram (New_Subp);
15295 Set_Requires_Overriding (New_Subp);
15298 elsif Ada_Version < Ada_2005
15299 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15300 or else (Is_Tagged_Type (Derived_Type)
15301 and then Etype (New_Subp) = Derived_Type
15302 and then No (Actual_Subp)))
15304 Set_Is_Abstract_Subprogram (New_Subp);
15306 -- AI05-0097 : an inherited operation that dispatches on result is
15307 -- abstract if the derived type is abstract, even if the parent type
15308 -- is concrete and the derived type is a null extension.
15310 elsif Has_Controlling_Result (Alias (New_Subp))
15311 and then Is_Abstract_Type (Etype (New_Subp))
15313 Set_Is_Abstract_Subprogram (New_Subp);
15315 -- Finally, if the parent type is abstract we must verify that all
15316 -- inherited operations are either non-abstract or overridden, or that
15317 -- the derived type itself is abstract (this check is performed at the
15318 -- end of a package declaration, in Check_Abstract_Overriding). A
15319 -- private overriding in the parent type will not be visible in the
15320 -- derivation if we are not in an inner package or in a child unit of
15321 -- the parent type, in which case the abstractness of the inherited
15322 -- operation is carried to the new subprogram.
15324 elsif Is_Abstract_Type (Parent_Type)
15325 and then not In_Open_Scopes (Scope (Parent_Type))
15326 and then Is_Private_Overriding
15327 and then Is_Abstract_Subprogram (Visible_Subp)
15329 if No (Actual_Subp) then
15330 Set_Alias (New_Subp, Visible_Subp);
15331 Set_Is_Abstract_Subprogram (New_Subp, True);
15334 -- If this is a derivation for an instance of a formal derived
15335 -- type, abstractness comes from the primitive operation of the
15336 -- actual, not from the operation inherited from the ancestor.
15338 Set_Is_Abstract_Subprogram
15339 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15343 New_Overloaded_Entity (New_Subp, Derived_Type);
15345 -- Ada RM 6.1.1 (15): If a subprogram inherits nonconforming class-wide
15346 -- preconditions and the derived type is abstract, the derived operation
15347 -- is abstract as well if parent subprogram is not abstract or null.
15349 if Is_Abstract_Type (Derived_Type)
15350 and then Has_Non_Trivial_Precondition (Parent_Subp)
15351 and then Present (Interfaces (Derived_Type))
15353 Set_Is_Dispatching_Operation (New_Subp);
15356 Iface_Prim : constant Entity_Id := Covered_Interface_Op (New_Subp);
15359 if Present (Iface_Prim)
15360 and then Has_Non_Trivial_Precondition (Iface_Prim)
15362 Set_Is_Abstract_Subprogram (New_Subp);
15367 -- Check for case of a derived subprogram for the instantiation of a
15368 -- formal derived tagged type, if so mark the subprogram as dispatching
15369 -- and inherit the dispatching attributes of the actual subprogram. The
15370 -- derived subprogram is effectively renaming of the actual subprogram,
15371 -- so it needs to have the same attributes as the actual.
15373 if Present (Actual_Subp)
15374 and then Is_Dispatching_Operation (Actual_Subp)
15376 Set_Is_Dispatching_Operation (New_Subp);
15378 if Present (DTC_Entity (Actual_Subp)) then
15379 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15380 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15384 -- Indicate that a derived subprogram does not require a body and that
15385 -- it does not require processing of default expressions.
15387 Set_Has_Completion (New_Subp);
15388 Set_Default_Expressions_Processed (New_Subp);
15390 if Ekind (New_Subp) = E_Function then
15391 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15393 end Derive_Subprogram;
15395 ------------------------
15396 -- Derive_Subprograms --
15397 ------------------------
15399 procedure Derive_Subprograms
15400 (Parent_Type : Entity_Id;
15401 Derived_Type : Entity_Id;
15402 Generic_Actual : Entity_Id := Empty)
15404 Op_List : constant Elist_Id :=
15405 Collect_Primitive_Operations (Parent_Type);
15407 function Check_Derived_Type return Boolean;
15408 -- Check that all the entities derived from Parent_Type are found in
15409 -- the list of primitives of Derived_Type exactly in the same order.
15411 procedure Derive_Interface_Subprogram
15412 (New_Subp : out Entity_Id;
15414 Actual_Subp : Entity_Id);
15415 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15416 -- (which is an interface primitive). If Generic_Actual is present then
15417 -- Actual_Subp is the actual subprogram corresponding with the generic
15418 -- subprogram Subp.
15420 ------------------------
15421 -- Check_Derived_Type --
15422 ------------------------
15424 function Check_Derived_Type return Boolean is
15428 New_Subp : Entity_Id;
15433 -- Traverse list of entities in the current scope searching for
15434 -- an incomplete type whose full-view is derived type.
15436 E := First_Entity (Scope (Derived_Type));
15437 while Present (E) and then E /= Derived_Type loop
15438 if Ekind (E) = E_Incomplete_Type
15439 and then Present (Full_View (E))
15440 and then Full_View (E) = Derived_Type
15442 -- Disable this test if Derived_Type completes an incomplete
15443 -- type because in such case more primitives can be added
15444 -- later to the list of primitives of Derived_Type by routine
15445 -- Process_Incomplete_Dependents
15450 E := Next_Entity (E);
15453 List := Collect_Primitive_Operations (Derived_Type);
15454 Elmt := First_Elmt (List);
15456 Op_Elmt := First_Elmt (Op_List);
15457 while Present (Op_Elmt) loop
15458 Subp := Node (Op_Elmt);
15459 New_Subp := Node (Elmt);
15461 -- At this early stage Derived_Type has no entities with attribute
15462 -- Interface_Alias. In addition, such primitives are always
15463 -- located at the end of the list of primitives of Parent_Type.
15464 -- Therefore, if found we can safely stop processing pending
15467 exit when Present (Interface_Alias (Subp));
15469 -- Handle hidden entities
15471 if not Is_Predefined_Dispatching_Operation (Subp)
15472 and then Is_Hidden (Subp)
15474 if Present (New_Subp)
15475 and then Primitive_Names_Match (Subp, New_Subp)
15481 if not Present (New_Subp)
15482 or else Ekind (Subp) /= Ekind (New_Subp)
15483 or else not Primitive_Names_Match (Subp, New_Subp)
15491 Next_Elmt (Op_Elmt);
15495 end Check_Derived_Type;
15497 ---------------------------------
15498 -- Derive_Interface_Subprogram --
15499 ---------------------------------
15501 procedure Derive_Interface_Subprogram
15502 (New_Subp : out Entity_Id;
15504 Actual_Subp : Entity_Id)
15506 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15507 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15510 pragma Assert (Is_Interface (Iface_Type));
15513 (New_Subp => New_Subp,
15514 Parent_Subp => Iface_Subp,
15515 Derived_Type => Derived_Type,
15516 Parent_Type => Iface_Type,
15517 Actual_Subp => Actual_Subp);
15519 -- Given that this new interface entity corresponds with a primitive
15520 -- of the parent that was not overridden we must leave it associated
15521 -- with its parent primitive to ensure that it will share the same
15522 -- dispatch table slot when overridden. We must set the Alias to Subp
15523 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15524 -- (in case we inherited Subp from Iface_Type via a nonabstract
15525 -- generic formal type).
15527 if No (Actual_Subp) then
15528 Set_Alias (New_Subp, Subp);
15531 T : Entity_Id := Find_Dispatching_Type (Subp);
15533 while Etype (T) /= T loop
15534 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15535 Set_Is_Abstract_Subprogram (New_Subp, False);
15543 -- For instantiations this is not needed since the previous call to
15544 -- Derive_Subprogram leaves the entity well decorated.
15547 pragma Assert (Alias (New_Subp) = Actual_Subp);
15550 end Derive_Interface_Subprogram;
15554 Alias_Subp : Entity_Id;
15555 Act_List : Elist_Id;
15556 Act_Elmt : Elmt_Id;
15557 Act_Subp : Entity_Id := Empty;
15559 Need_Search : Boolean := False;
15560 New_Subp : Entity_Id := Empty;
15561 Parent_Base : Entity_Id;
15564 -- Start of processing for Derive_Subprograms
15567 if Ekind (Parent_Type) = E_Record_Type_With_Private
15568 and then Has_Discriminants (Parent_Type)
15569 and then Present (Full_View (Parent_Type))
15571 Parent_Base := Full_View (Parent_Type);
15573 Parent_Base := Parent_Type;
15576 if Present (Generic_Actual) then
15577 Act_List := Collect_Primitive_Operations (Generic_Actual);
15578 Act_Elmt := First_Elmt (Act_List);
15580 Act_List := No_Elist;
15581 Act_Elmt := No_Elmt;
15584 -- Derive primitives inherited from the parent. Note that if the generic
15585 -- actual is present, this is not really a type derivation, it is a
15586 -- completion within an instance.
15588 -- Case 1: Derived_Type does not implement interfaces
15590 if not Is_Tagged_Type (Derived_Type)
15591 or else (not Has_Interfaces (Derived_Type)
15592 and then not (Present (Generic_Actual)
15593 and then Has_Interfaces (Generic_Actual)))
15595 Elmt := First_Elmt (Op_List);
15596 while Present (Elmt) loop
15597 Subp := Node (Elmt);
15599 -- Literals are derived earlier in the process of building the
15600 -- derived type, and are skipped here.
15602 if Ekind (Subp) = E_Enumeration_Literal then
15605 -- The actual is a direct descendant and the common primitive
15606 -- operations appear in the same order.
15608 -- If the generic parent type is present, the derived type is an
15609 -- instance of a formal derived type, and within the instance its
15610 -- operations are those of the actual. We derive from the formal
15611 -- type but make the inherited operations aliases of the
15612 -- corresponding operations of the actual.
15615 pragma Assert (No (Node (Act_Elmt))
15616 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15619 (Subp, Node (Act_Elmt),
15620 Skip_Controlling_Formals => True)));
15623 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15625 if Present (Act_Elmt) then
15626 Next_Elmt (Act_Elmt);
15633 -- Case 2: Derived_Type implements interfaces
15636 -- If the parent type has no predefined primitives we remove
15637 -- predefined primitives from the list of primitives of generic
15638 -- actual to simplify the complexity of this algorithm.
15640 if Present (Generic_Actual) then
15642 Has_Predefined_Primitives : Boolean := False;
15645 -- Check if the parent type has predefined primitives
15647 Elmt := First_Elmt (Op_List);
15648 while Present (Elmt) loop
15649 Subp := Node (Elmt);
15651 if Is_Predefined_Dispatching_Operation (Subp)
15652 and then not Comes_From_Source (Ultimate_Alias (Subp))
15654 Has_Predefined_Primitives := True;
15661 -- Remove predefined primitives of Generic_Actual. We must use
15662 -- an auxiliary list because in case of tagged types the value
15663 -- returned by Collect_Primitive_Operations is the value stored
15664 -- in its Primitive_Operations attribute (and we don't want to
15665 -- modify its current contents).
15667 if not Has_Predefined_Primitives then
15669 Aux_List : constant Elist_Id := New_Elmt_List;
15672 Elmt := First_Elmt (Act_List);
15673 while Present (Elmt) loop
15674 Subp := Node (Elmt);
15676 if not Is_Predefined_Dispatching_Operation (Subp)
15677 or else Comes_From_Source (Subp)
15679 Append_Elmt (Subp, Aux_List);
15685 Act_List := Aux_List;
15689 Act_Elmt := First_Elmt (Act_List);
15690 Act_Subp := Node (Act_Elmt);
15694 -- Stage 1: If the generic actual is not present we derive the
15695 -- primitives inherited from the parent type. If the generic parent
15696 -- type is present, the derived type is an instance of a formal
15697 -- derived type, and within the instance its operations are those of
15698 -- the actual. We derive from the formal type but make the inherited
15699 -- operations aliases of the corresponding operations of the actual.
15701 Elmt := First_Elmt (Op_List);
15702 while Present (Elmt) loop
15703 Subp := Node (Elmt);
15704 Alias_Subp := Ultimate_Alias (Subp);
15706 -- Do not derive internal entities of the parent that link
15707 -- interface primitives with their covering primitive. These
15708 -- entities will be added to this type when frozen.
15710 if Present (Interface_Alias (Subp)) then
15714 -- If the generic actual is present find the corresponding
15715 -- operation in the generic actual. If the parent type is a
15716 -- direct ancestor of the derived type then, even if it is an
15717 -- interface, the operations are inherited from the primary
15718 -- dispatch table and are in the proper order. If we detect here
15719 -- that primitives are not in the same order we traverse the list
15720 -- of primitive operations of the actual to find the one that
15721 -- implements the interface primitive.
15725 (Present (Generic_Actual)
15726 and then Present (Act_Subp)
15728 (Primitive_Names_Match (Subp, Act_Subp)
15730 Type_Conformant (Subp, Act_Subp,
15731 Skip_Controlling_Formals => True)))
15733 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15734 Use_Full_View => True));
15736 -- Remember that we need searching for all pending primitives
15738 Need_Search := True;
15740 -- Handle entities associated with interface primitives
15742 if Present (Alias_Subp)
15743 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15744 and then not Is_Predefined_Dispatching_Operation (Subp)
15746 -- Search for the primitive in the homonym chain
15749 Find_Primitive_Covering_Interface
15750 (Tagged_Type => Generic_Actual,
15751 Iface_Prim => Alias_Subp);
15753 -- Previous search may not locate primitives covering
15754 -- interfaces defined in generics units or instantiations.
15755 -- (it fails if the covering primitive has formals whose
15756 -- type is also defined in generics or instantiations).
15757 -- In such case we search in the list of primitives of the
15758 -- generic actual for the internal entity that links the
15759 -- interface primitive and the covering primitive.
15762 and then Is_Generic_Type (Parent_Type)
15764 -- This code has been designed to handle only generic
15765 -- formals that implement interfaces that are defined
15766 -- in a generic unit or instantiation. If this code is
15767 -- needed for other cases we must review it because
15768 -- (given that it relies on Original_Location to locate
15769 -- the primitive of Generic_Actual that covers the
15770 -- interface) it could leave linked through attribute
15771 -- Alias entities of unrelated instantiations).
15775 (Scope (Find_Dispatching_Type (Alias_Subp)))
15777 Instantiation_Depth
15778 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15781 Iface_Prim_Loc : constant Source_Ptr :=
15782 Original_Location (Sloc (Alias_Subp));
15789 First_Elmt (Primitive_Operations (Generic_Actual));
15791 Search : while Present (Elmt) loop
15792 Prim := Node (Elmt);
15794 if Present (Interface_Alias (Prim))
15795 and then Original_Location
15796 (Sloc (Interface_Alias (Prim))) =
15799 Act_Subp := Alias (Prim);
15808 pragma Assert (Present (Act_Subp)
15809 or else Is_Abstract_Type (Generic_Actual)
15810 or else Serious_Errors_Detected > 0);
15812 -- Handle predefined primitives plus the rest of user-defined
15816 Act_Elmt := First_Elmt (Act_List);
15817 while Present (Act_Elmt) loop
15818 Act_Subp := Node (Act_Elmt);
15820 exit when Primitive_Names_Match (Subp, Act_Subp)
15821 and then Type_Conformant
15823 Skip_Controlling_Formals => True)
15824 and then No (Interface_Alias (Act_Subp));
15826 Next_Elmt (Act_Elmt);
15829 if No (Act_Elmt) then
15835 -- Case 1: If the parent is a limited interface then it has the
15836 -- predefined primitives of synchronized interfaces. However, the
15837 -- actual type may be a non-limited type and hence it does not
15838 -- have such primitives.
15840 if Present (Generic_Actual)
15841 and then not Present (Act_Subp)
15842 and then Is_Limited_Interface (Parent_Base)
15843 and then Is_Predefined_Interface_Primitive (Subp)
15847 -- Case 2: Inherit entities associated with interfaces that were
15848 -- not covered by the parent type. We exclude here null interface
15849 -- primitives because they do not need special management.
15851 -- We also exclude interface operations that are renamings. If the
15852 -- subprogram is an explicit renaming of an interface primitive,
15853 -- it is a regular primitive operation, and the presence of its
15854 -- alias is not relevant: it has to be derived like any other
15857 elsif Present (Alias (Subp))
15858 and then Nkind (Unit_Declaration_Node (Subp)) /=
15859 N_Subprogram_Renaming_Declaration
15860 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15862 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15863 and then Null_Present (Parent (Alias_Subp)))
15865 -- If this is an abstract private type then we transfer the
15866 -- derivation of the interface primitive from the partial view
15867 -- to the full view. This is safe because all the interfaces
15868 -- must be visible in the partial view. Done to avoid adding
15869 -- a new interface derivation to the private part of the
15870 -- enclosing package; otherwise this new derivation would be
15871 -- decorated as hidden when the analysis of the enclosing
15872 -- package completes.
15874 if Is_Abstract_Type (Derived_Type)
15875 and then In_Private_Part (Current_Scope)
15876 and then Has_Private_Declaration (Derived_Type)
15879 Partial_View : Entity_Id;
15884 Partial_View := First_Entity (Current_Scope);
15886 exit when No (Partial_View)
15887 or else (Has_Private_Declaration (Partial_View)
15889 Full_View (Partial_View) = Derived_Type);
15891 Next_Entity (Partial_View);
15894 -- If the partial view was not found then the source code
15895 -- has errors and the derivation is not needed.
15897 if Present (Partial_View) then
15899 First_Elmt (Primitive_Operations (Partial_View));
15900 while Present (Elmt) loop
15901 Ent := Node (Elmt);
15903 if Present (Alias (Ent))
15904 and then Ultimate_Alias (Ent) = Alias (Subp)
15907 (Ent, Primitive_Operations (Derived_Type));
15914 -- If the interface primitive was not found in the
15915 -- partial view then this interface primitive was
15916 -- overridden. We add a derivation to activate in
15917 -- Derive_Progenitor_Subprograms the machinery to
15921 Derive_Interface_Subprogram
15922 (New_Subp => New_Subp,
15924 Actual_Subp => Act_Subp);
15929 Derive_Interface_Subprogram
15930 (New_Subp => New_Subp,
15932 Actual_Subp => Act_Subp);
15935 -- Case 3: Common derivation
15939 (New_Subp => New_Subp,
15940 Parent_Subp => Subp,
15941 Derived_Type => Derived_Type,
15942 Parent_Type => Parent_Base,
15943 Actual_Subp => Act_Subp);
15946 -- No need to update Act_Elm if we must search for the
15947 -- corresponding operation in the generic actual
15950 and then Present (Act_Elmt)
15952 Next_Elmt (Act_Elmt);
15953 Act_Subp := Node (Act_Elmt);
15960 -- Inherit additional operations from progenitors. If the derived
15961 -- type is a generic actual, there are not new primitive operations
15962 -- for the type because it has those of the actual, and therefore
15963 -- nothing needs to be done. The renamings generated above are not
15964 -- primitive operations, and their purpose is simply to make the
15965 -- proper operations visible within an instantiation.
15967 if No (Generic_Actual) then
15968 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15972 -- Final check: Direct descendants must have their primitives in the
15973 -- same order. We exclude from this test untagged types and instances
15974 -- of formal derived types. We skip this test if we have already
15975 -- reported serious errors in the sources.
15977 pragma Assert (not Is_Tagged_Type (Derived_Type)
15978 or else Present (Generic_Actual)
15979 or else Serious_Errors_Detected > 0
15980 or else Check_Derived_Type);
15981 end Derive_Subprograms;
15983 --------------------------------
15984 -- Derived_Standard_Character --
15985 --------------------------------
15987 procedure Derived_Standard_Character
15989 Parent_Type : Entity_Id;
15990 Derived_Type : Entity_Id)
15992 Loc : constant Source_Ptr := Sloc (N);
15993 Def : constant Node_Id := Type_Definition (N);
15994 Indic : constant Node_Id := Subtype_Indication (Def);
15995 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15996 Implicit_Base : constant Entity_Id :=
15998 (E_Enumeration_Type, N, Derived_Type, 'B');
16004 Discard_Node (Process_Subtype (Indic, N));
16006 Set_Etype (Implicit_Base, Parent_Base);
16007 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
16008 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
16010 Set_Is_Character_Type (Implicit_Base, True);
16011 Set_Has_Delayed_Freeze (Implicit_Base);
16013 -- The bounds of the implicit base are the bounds of the parent base.
16014 -- Note that their type is the parent base.
16016 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
16017 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
16019 Set_Scalar_Range (Implicit_Base,
16022 High_Bound => Hi));
16024 Conditional_Delay (Derived_Type, Parent_Type);
16026 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
16027 Set_Etype (Derived_Type, Implicit_Base);
16028 Set_Size_Info (Derived_Type, Parent_Type);
16030 if Unknown_RM_Size (Derived_Type) then
16031 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
16034 Set_Is_Character_Type (Derived_Type, True);
16036 if Nkind (Indic) /= N_Subtype_Indication then
16038 -- If no explicit constraint, the bounds are those
16039 -- of the parent type.
16041 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
16042 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
16043 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
16046 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
16048 -- Because the implicit base is used in the conversion of the bounds, we
16049 -- have to freeze it now. This is similar to what is done for numeric
16050 -- types, and it equally suspicious, but otherwise a non-static bound
16051 -- will have a reference to an unfrozen type, which is rejected by Gigi
16052 -- (???). This requires specific care for definition of stream
16053 -- attributes. For details, see comments at the end of
16054 -- Build_Derived_Numeric_Type.
16056 Freeze_Before (N, Implicit_Base);
16057 end Derived_Standard_Character;
16059 ------------------------------
16060 -- Derived_Type_Declaration --
16061 ------------------------------
16063 procedure Derived_Type_Declaration
16066 Is_Completion : Boolean)
16068 Parent_Type : Entity_Id;
16070 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
16071 -- Check whether the parent type is a generic formal, or derives
16072 -- directly or indirectly from one.
16074 ------------------------
16075 -- Comes_From_Generic --
16076 ------------------------
16078 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
16080 if Is_Generic_Type (Typ) then
16083 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
16086 elsif Is_Private_Type (Typ)
16087 and then Present (Full_View (Typ))
16088 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
16092 elsif Is_Generic_Actual_Type (Typ) then
16098 end Comes_From_Generic;
16102 Def : constant Node_Id := Type_Definition (N);
16103 Iface_Def : Node_Id;
16104 Indic : constant Node_Id := Subtype_Indication (Def);
16105 Extension : constant Node_Id := Record_Extension_Part (Def);
16106 Parent_Node : Node_Id;
16109 -- Start of processing for Derived_Type_Declaration
16112 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
16114 -- Ada 2005 (AI-251): In case of interface derivation check that the
16115 -- parent is also an interface.
16117 if Interface_Present (Def) then
16118 Check_SPARK_05_Restriction ("interface is not allowed", Def);
16120 if not Is_Interface (Parent_Type) then
16121 Diagnose_Interface (Indic, Parent_Type);
16124 Parent_Node := Parent (Base_Type (Parent_Type));
16125 Iface_Def := Type_Definition (Parent_Node);
16127 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
16128 -- other limited interfaces.
16130 if Limited_Present (Def) then
16131 if Limited_Present (Iface_Def) then
16134 elsif Protected_Present (Iface_Def) then
16136 ("descendant of & must be declared as a protected "
16137 & "interface", N, Parent_Type);
16139 elsif Synchronized_Present (Iface_Def) then
16141 ("descendant of & must be declared as a synchronized "
16142 & "interface", N, Parent_Type);
16144 elsif Task_Present (Iface_Def) then
16146 ("descendant of & must be declared as a task interface",
16151 ("(Ada 2005) limited interface cannot inherit from "
16152 & "non-limited interface", Indic);
16155 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
16156 -- from non-limited or limited interfaces.
16158 elsif not Protected_Present (Def)
16159 and then not Synchronized_Present (Def)
16160 and then not Task_Present (Def)
16162 if Limited_Present (Iface_Def) then
16165 elsif Protected_Present (Iface_Def) then
16167 ("descendant of & must be declared as a protected "
16168 & "interface", N, Parent_Type);
16170 elsif Synchronized_Present (Iface_Def) then
16172 ("descendant of & must be declared as a synchronized "
16173 & "interface", N, Parent_Type);
16175 elsif Task_Present (Iface_Def) then
16177 ("descendant of & must be declared as a task interface",
16186 if Is_Tagged_Type (Parent_Type)
16187 and then Is_Concurrent_Type (Parent_Type)
16188 and then not Is_Interface (Parent_Type)
16191 ("parent type of a record extension cannot be a synchronized "
16192 & "tagged type (RM 3.9.1 (3/1))", N);
16193 Set_Etype (T, Any_Type);
16197 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
16200 if Is_Tagged_Type (Parent_Type)
16201 and then Is_Non_Empty_List (Interface_List (Def))
16208 Intf := First (Interface_List (Def));
16209 while Present (Intf) loop
16210 T := Find_Type_Of_Subtype_Indic (Intf);
16212 if not Is_Interface (T) then
16213 Diagnose_Interface (Intf, T);
16215 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
16216 -- a limited type from having a nonlimited progenitor.
16218 elsif (Limited_Present (Def)
16219 or else (not Is_Interface (Parent_Type)
16220 and then Is_Limited_Type (Parent_Type)))
16221 and then not Is_Limited_Interface (T)
16224 ("progenitor interface& of limited type must be limited",
16233 if Parent_Type = Any_Type
16234 or else Etype (Parent_Type) = Any_Type
16235 or else (Is_Class_Wide_Type (Parent_Type)
16236 and then Etype (Parent_Type) = T)
16238 -- If Parent_Type is undefined or illegal, make new type into a
16239 -- subtype of Any_Type, and set a few attributes to prevent cascaded
16240 -- errors. If this is a self-definition, emit error now.
16242 if T = Parent_Type or else T = Etype (Parent_Type) then
16243 Error_Msg_N ("type cannot be used in its own definition", Indic);
16246 Set_Ekind (T, Ekind (Parent_Type));
16247 Set_Etype (T, Any_Type);
16248 Set_Scalar_Range (T, Scalar_Range (Any_Type));
16250 if Is_Tagged_Type (T)
16251 and then Is_Record_Type (T)
16253 Set_Direct_Primitive_Operations (T, New_Elmt_List);
16259 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
16260 -- an interface is special because the list of interfaces in the full
16261 -- view can be given in any order. For example:
16263 -- type A is interface;
16264 -- type B is interface and A;
16265 -- type D is new B with private;
16267 -- type D is new A and B with null record; -- 1 --
16269 -- In this case we perform the following transformation of -1-:
16271 -- type D is new B and A with null record;
16273 -- If the parent of the full-view covers the parent of the partial-view
16274 -- we have two possible cases:
16276 -- 1) They have the same parent
16277 -- 2) The parent of the full-view implements some further interfaces
16279 -- In both cases we do not need to perform the transformation. In the
16280 -- first case the source program is correct and the transformation is
16281 -- not needed; in the second case the source program does not fulfill
16282 -- the no-hidden interfaces rule (AI-396) and the error will be reported
16285 -- This transformation not only simplifies the rest of the analysis of
16286 -- this type declaration but also simplifies the correct generation of
16287 -- the object layout to the expander.
16289 if In_Private_Part (Current_Scope)
16290 and then Is_Interface (Parent_Type)
16294 Partial_View : Entity_Id;
16295 Partial_View_Parent : Entity_Id;
16296 New_Iface : Node_Id;
16299 -- Look for the associated private type declaration
16301 Partial_View := First_Entity (Current_Scope);
16303 exit when No (Partial_View)
16304 or else (Has_Private_Declaration (Partial_View)
16305 and then Full_View (Partial_View) = T);
16307 Next_Entity (Partial_View);
16310 -- If the partial view was not found then the source code has
16311 -- errors and the transformation is not needed.
16313 if Present (Partial_View) then
16314 Partial_View_Parent := Etype (Partial_View);
16316 -- If the parent of the full-view covers the parent of the
16317 -- partial-view we have nothing else to do.
16319 if Interface_Present_In_Ancestor
16320 (Parent_Type, Partial_View_Parent)
16324 -- Traverse the list of interfaces of the full-view to look
16325 -- for the parent of the partial-view and perform the tree
16329 Iface := First (Interface_List (Def));
16330 while Present (Iface) loop
16331 if Etype (Iface) = Etype (Partial_View) then
16332 Rewrite (Subtype_Indication (Def),
16333 New_Copy (Subtype_Indication
16334 (Parent (Partial_View))));
16337 Make_Identifier (Sloc (N), Chars (Parent_Type));
16338 Append (New_Iface, Interface_List (Def));
16340 -- Analyze the transformed code
16342 Derived_Type_Declaration (T, N, Is_Completion);
16353 -- Only composite types other than array types are allowed to have
16356 if Present (Discriminant_Specifications (N)) then
16357 if (Is_Elementary_Type (Parent_Type)
16359 Is_Array_Type (Parent_Type))
16360 and then not Error_Posted (N)
16363 ("elementary or array type cannot have discriminants",
16364 Defining_Identifier (First (Discriminant_Specifications (N))));
16365 Set_Has_Discriminants (T, False);
16367 -- The type is allowed to have discriminants
16370 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16374 -- In Ada 83, a derived type defined in a package specification cannot
16375 -- be used for further derivation until the end of its visible part.
16376 -- Note that derivation in the private part of the package is allowed.
16378 if Ada_Version = Ada_83
16379 and then Is_Derived_Type (Parent_Type)
16380 and then In_Visible_Part (Scope (Parent_Type))
16382 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16384 ("(Ada 83): premature use of type for derivation", Indic);
16388 -- Check for early use of incomplete or private type
16390 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16391 Error_Msg_N ("premature derivation of incomplete type", Indic);
16394 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16395 and then not Comes_From_Generic (Parent_Type))
16396 or else Has_Private_Component (Parent_Type)
16398 -- The ancestor type of a formal type can be incomplete, in which
16399 -- case only the operations of the partial view are available in the
16400 -- generic. Subsequent checks may be required when the full view is
16401 -- analyzed to verify that a derivation from a tagged type has an
16404 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16407 elsif No (Underlying_Type (Parent_Type))
16408 or else Has_Private_Component (Parent_Type)
16411 ("premature derivation of derived or private type", Indic);
16413 -- Flag the type itself as being in error, this prevents some
16414 -- nasty problems with subsequent uses of the malformed type.
16416 Set_Error_Posted (T);
16418 -- Check that within the immediate scope of an untagged partial
16419 -- view it's illegal to derive from the partial view if the
16420 -- full view is tagged. (7.3(7))
16422 -- We verify that the Parent_Type is a partial view by checking
16423 -- that it is not a Full_Type_Declaration (i.e. a private type or
16424 -- private extension declaration), to distinguish a partial view
16425 -- from a derivation from a private type which also appears as
16426 -- E_Private_Type. If the parent base type is not declared in an
16427 -- enclosing scope there is no need to check.
16429 elsif Present (Full_View (Parent_Type))
16430 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16431 and then not Is_Tagged_Type (Parent_Type)
16432 and then Is_Tagged_Type (Full_View (Parent_Type))
16433 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16436 ("premature derivation from type with tagged full view",
16441 -- Check that form of derivation is appropriate
16443 Taggd := Is_Tagged_Type (Parent_Type);
16445 -- Set the parent type to the class-wide type's specific type in this
16446 -- case to prevent cascading errors
16448 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16449 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16450 Set_Etype (T, Etype (Parent_Type));
16454 if Present (Extension) and then not Taggd then
16456 ("type derived from untagged type cannot have extension", Indic);
16458 elsif No (Extension) and then Taggd then
16460 -- If this declaration is within a private part (or body) of a
16461 -- generic instantiation then the derivation is allowed (the parent
16462 -- type can only appear tagged in this case if it's a generic actual
16463 -- type, since it would otherwise have been rejected in the analysis
16464 -- of the generic template).
16466 if not Is_Generic_Actual_Type (Parent_Type)
16467 or else In_Visible_Part (Scope (Parent_Type))
16469 if Is_Class_Wide_Type (Parent_Type) then
16471 ("parent type must not be a class-wide type", Indic);
16473 -- Use specific type to prevent cascaded errors.
16475 Parent_Type := Etype (Parent_Type);
16479 ("type derived from tagged type must have extension", Indic);
16484 -- AI-443: Synchronized formal derived types require a private
16485 -- extension. There is no point in checking the ancestor type or
16486 -- the progenitors since the construct is wrong to begin with.
16488 if Ada_Version >= Ada_2005
16489 and then Is_Generic_Type (T)
16490 and then Present (Original_Node (N))
16493 Decl : constant Node_Id := Original_Node (N);
16496 if Nkind (Decl) = N_Formal_Type_Declaration
16497 and then Nkind (Formal_Type_Definition (Decl)) =
16498 N_Formal_Derived_Type_Definition
16499 and then Synchronized_Present (Formal_Type_Definition (Decl))
16500 and then No (Extension)
16502 -- Avoid emitting a duplicate error message
16504 and then not Error_Posted (Indic)
16507 ("synchronized derived type must have extension", N);
16512 if Null_Exclusion_Present (Def)
16513 and then not Is_Access_Type (Parent_Type)
16515 Error_Msg_N ("null exclusion can only apply to an access type", N);
16518 -- Avoid deriving parent primitives of underlying record views
16520 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16521 Derive_Subps => not Is_Underlying_Record_View (T));
16523 -- AI-419: The parent type of an explicitly limited derived type must
16524 -- be a limited type or a limited interface.
16526 if Limited_Present (Def) then
16527 Set_Is_Limited_Record (T);
16529 if Is_Interface (T) then
16530 Set_Is_Limited_Interface (T);
16533 if not Is_Limited_Type (Parent_Type)
16535 (not Is_Interface (Parent_Type)
16536 or else not Is_Limited_Interface (Parent_Type))
16538 -- AI05-0096: a derivation in the private part of an instance is
16539 -- legal if the generic formal is untagged limited, and the actual
16542 if Is_Generic_Actual_Type (Parent_Type)
16543 and then In_Private_Part (Current_Scope)
16546 (Generic_Parent_Type (Parent (Parent_Type)))
16552 ("parent type& of limited type must be limited",
16558 -- In SPARK, there are no derived type definitions other than type
16559 -- extensions of tagged record types.
16561 if No (Extension) then
16562 Check_SPARK_05_Restriction
16563 ("derived type is not allowed", Original_Node (N));
16565 end Derived_Type_Declaration;
16567 ------------------------
16568 -- Diagnose_Interface --
16569 ------------------------
16571 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16573 if not Is_Interface (E) and then E /= Any_Type then
16574 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16576 end Diagnose_Interface;
16578 ----------------------------------
16579 -- Enumeration_Type_Declaration --
16580 ----------------------------------
16582 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16589 -- Create identifier node representing lower bound
16591 B_Node := New_Node (N_Identifier, Sloc (Def));
16592 L := First (Literals (Def));
16593 Set_Chars (B_Node, Chars (L));
16594 Set_Entity (B_Node, L);
16595 Set_Etype (B_Node, T);
16596 Set_Is_Static_Expression (B_Node, True);
16598 R_Node := New_Node (N_Range, Sloc (Def));
16599 Set_Low_Bound (R_Node, B_Node);
16601 Set_Ekind (T, E_Enumeration_Type);
16602 Set_First_Literal (T, L);
16604 Set_Is_Constrained (T);
16608 -- Loop through literals of enumeration type setting pos and rep values
16609 -- except that if the Ekind is already set, then it means the literal
16610 -- was already constructed (case of a derived type declaration and we
16611 -- should not disturb the Pos and Rep values.
16613 while Present (L) loop
16614 if Ekind (L) /= E_Enumeration_Literal then
16615 Set_Ekind (L, E_Enumeration_Literal);
16616 Set_Enumeration_Pos (L, Ev);
16617 Set_Enumeration_Rep (L, Ev);
16618 Set_Is_Known_Valid (L, True);
16622 New_Overloaded_Entity (L);
16623 Generate_Definition (L);
16624 Set_Convention (L, Convention_Intrinsic);
16626 -- Case of character literal
16628 if Nkind (L) = N_Defining_Character_Literal then
16629 Set_Is_Character_Type (T, True);
16631 -- Check violation of No_Wide_Characters
16633 if Restriction_Check_Required (No_Wide_Characters) then
16634 Get_Name_String (Chars (L));
16636 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16637 Check_Restriction (No_Wide_Characters, L);
16646 -- Now create a node representing upper bound
16648 B_Node := New_Node (N_Identifier, Sloc (Def));
16649 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16650 Set_Entity (B_Node, Last (Literals (Def)));
16651 Set_Etype (B_Node, T);
16652 Set_Is_Static_Expression (B_Node, True);
16654 Set_High_Bound (R_Node, B_Node);
16656 -- Initialize various fields of the type. Some of this information
16657 -- may be overwritten later through rep.clauses.
16659 Set_Scalar_Range (T, R_Node);
16660 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16661 Set_Enum_Esize (T);
16662 Set_Enum_Pos_To_Rep (T, Empty);
16664 -- Set Discard_Names if configuration pragma set, or if there is
16665 -- a parameterless pragma in the current declarative region
16667 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16668 Set_Discard_Names (T);
16671 -- Process end label if there is one
16673 if Present (Def) then
16674 Process_End_Label (Def, 'e', T);
16676 end Enumeration_Type_Declaration;
16678 ---------------------------------
16679 -- Expand_To_Stored_Constraint --
16680 ---------------------------------
16682 function Expand_To_Stored_Constraint
16684 Constraint : Elist_Id) return Elist_Id
16686 Explicitly_Discriminated_Type : Entity_Id;
16687 Expansion : Elist_Id;
16688 Discriminant : Entity_Id;
16690 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16691 -- Find the nearest type that actually specifies discriminants
16693 ---------------------------------
16694 -- Type_With_Explicit_Discrims --
16695 ---------------------------------
16697 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16698 Typ : constant E := Base_Type (Id);
16701 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16702 if Present (Full_View (Typ)) then
16703 return Type_With_Explicit_Discrims (Full_View (Typ));
16707 if Has_Discriminants (Typ) then
16712 if Etype (Typ) = Typ then
16714 elsif Has_Discriminants (Typ) then
16717 return Type_With_Explicit_Discrims (Etype (Typ));
16720 end Type_With_Explicit_Discrims;
16722 -- Start of processing for Expand_To_Stored_Constraint
16725 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16729 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16731 if No (Explicitly_Discriminated_Type) then
16735 Expansion := New_Elmt_List;
16738 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16739 while Present (Discriminant) loop
16741 (Get_Discriminant_Value
16742 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16744 Next_Stored_Discriminant (Discriminant);
16748 end Expand_To_Stored_Constraint;
16750 ---------------------------
16751 -- Find_Hidden_Interface --
16752 ---------------------------
16754 function Find_Hidden_Interface
16756 Dest : Elist_Id) return Entity_Id
16759 Iface_Elmt : Elmt_Id;
16762 if Present (Src) and then Present (Dest) then
16763 Iface_Elmt := First_Elmt (Src);
16764 while Present (Iface_Elmt) loop
16765 Iface := Node (Iface_Elmt);
16767 if Is_Interface (Iface)
16768 and then not Contain_Interface (Iface, Dest)
16773 Next_Elmt (Iface_Elmt);
16778 end Find_Hidden_Interface;
16780 --------------------
16781 -- Find_Type_Name --
16782 --------------------
16784 function Find_Type_Name (N : Node_Id) return Entity_Id is
16785 Id : constant Entity_Id := Defining_Identifier (N);
16786 New_Id : Entity_Id;
16788 Prev_Par : Node_Id;
16790 procedure Check_Duplicate_Aspects;
16791 -- Check that aspects specified in a completion have not been specified
16792 -- already in the partial view.
16794 procedure Tag_Mismatch;
16795 -- Diagnose a tagged partial view whose full view is untagged. We post
16796 -- the message on the full view, with a reference to the previous
16797 -- partial view. The partial view can be private or incomplete, and
16798 -- these are handled in a different manner, so we determine the position
16799 -- of the error message from the respective slocs of both.
16801 -----------------------------
16802 -- Check_Duplicate_Aspects --
16803 -----------------------------
16805 procedure Check_Duplicate_Aspects is
16806 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
16807 -- Return the corresponding aspect of the partial view which matches
16808 -- the aspect id of Asp. Return Empty is no such aspect exists.
16810 -----------------------------
16811 -- Get_Partial_View_Aspect --
16812 -----------------------------
16814 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
16815 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
16816 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
16817 Prev_Asp : Node_Id;
16820 if Present (Prev_Asps) then
16821 Prev_Asp := First (Prev_Asps);
16822 while Present (Prev_Asp) loop
16823 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
16832 end Get_Partial_View_Aspect;
16836 Full_Asps : constant List_Id := Aspect_Specifications (N);
16837 Full_Asp : Node_Id;
16838 Part_Asp : Node_Id;
16840 -- Start of processing for Check_Duplicate_Aspects
16843 if Present (Full_Asps) then
16844 Full_Asp := First (Full_Asps);
16845 while Present (Full_Asp) loop
16846 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
16848 -- An aspect and its class-wide counterpart are two distinct
16849 -- aspects and may apply to both views of an entity.
16851 if Present (Part_Asp)
16852 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
16855 ("aspect already specified in private declaration",
16862 if Has_Discriminants (Prev)
16863 and then not Has_Unknown_Discriminants (Prev)
16864 and then Get_Aspect_Id (Full_Asp) =
16865 Aspect_Implicit_Dereference
16868 ("cannot specify aspect if partial view has known "
16869 & "discriminants", Full_Asp);
16875 end Check_Duplicate_Aspects;
16881 procedure Tag_Mismatch is
16883 if Sloc (Prev) < Sloc (Id) then
16884 if Ada_Version >= Ada_2012
16885 and then Nkind (N) = N_Private_Type_Declaration
16888 ("declaration of private } must be a tagged type ", Id, Prev);
16891 ("full declaration of } must be a tagged type ", Id, Prev);
16895 if Ada_Version >= Ada_2012
16896 and then Nkind (N) = N_Private_Type_Declaration
16899 ("declaration of private } must be a tagged type ", Prev, Id);
16902 ("full declaration of } must be a tagged type ", Prev, Id);
16907 -- Start of processing for Find_Type_Name
16910 -- Find incomplete declaration, if one was given
16912 Prev := Current_Entity_In_Scope (Id);
16914 -- New type declaration
16920 -- Previous declaration exists
16923 Prev_Par := Parent (Prev);
16925 -- Error if not incomplete/private case except if previous
16926 -- declaration is implicit, etc. Enter_Name will emit error if
16929 if not Is_Incomplete_Or_Private_Type (Prev) then
16933 -- Check invalid completion of private or incomplete type
16935 elsif not Nkind_In (N, N_Full_Type_Declaration,
16936 N_Task_Type_Declaration,
16937 N_Protected_Type_Declaration)
16939 (Ada_Version < Ada_2012
16940 or else not Is_Incomplete_Type (Prev)
16941 or else not Nkind_In (N, N_Private_Type_Declaration,
16942 N_Private_Extension_Declaration))
16944 -- Completion must be a full type declarations (RM 7.3(4))
16946 Error_Msg_Sloc := Sloc (Prev);
16947 Error_Msg_NE ("invalid completion of }", Id, Prev);
16949 -- Set scope of Id to avoid cascaded errors. Entity is never
16950 -- examined again, except when saving globals in generics.
16952 Set_Scope (Id, Current_Scope);
16955 -- If this is a repeated incomplete declaration, no further
16956 -- checks are possible.
16958 if Nkind (N) = N_Incomplete_Type_Declaration then
16962 -- Case of full declaration of incomplete type
16964 elsif Ekind (Prev) = E_Incomplete_Type
16965 and then (Ada_Version < Ada_2012
16966 or else No (Full_View (Prev))
16967 or else not Is_Private_Type (Full_View (Prev)))
16969 -- Indicate that the incomplete declaration has a matching full
16970 -- declaration. The defining occurrence of the incomplete
16971 -- declaration remains the visible one, and the procedure
16972 -- Get_Full_View dereferences it whenever the type is used.
16974 if Present (Full_View (Prev)) then
16975 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16978 Set_Full_View (Prev, Id);
16979 Append_Entity (Id, Current_Scope);
16980 Set_Is_Public (Id, Is_Public (Prev));
16981 Set_Is_Internal (Id);
16984 -- If the incomplete view is tagged, a class_wide type has been
16985 -- created already. Use it for the private type as well, in order
16986 -- to prevent multiple incompatible class-wide types that may be
16987 -- created for self-referential anonymous access components.
16989 if Is_Tagged_Type (Prev)
16990 and then Present (Class_Wide_Type (Prev))
16992 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16993 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16995 -- Type of the class-wide type is the current Id. Previously
16996 -- this was not done for private declarations because of order-
16997 -- of-elaboration issues in the back end, but gigi now handles
17000 Set_Etype (Class_Wide_Type (Id), Id);
17003 -- Case of full declaration of private type
17006 -- If the private type was a completion of an incomplete type then
17007 -- update Prev to reference the private type
17009 if Ada_Version >= Ada_2012
17010 and then Ekind (Prev) = E_Incomplete_Type
17011 and then Present (Full_View (Prev))
17012 and then Is_Private_Type (Full_View (Prev))
17014 Prev := Full_View (Prev);
17015 Prev_Par := Parent (Prev);
17018 if Nkind (N) = N_Full_Type_Declaration
17020 (Type_Definition (N), N_Record_Definition,
17021 N_Derived_Type_Definition)
17022 and then Interface_Present (Type_Definition (N))
17025 ("completion of private type cannot be an interface", N);
17028 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
17029 if Etype (Prev) /= Prev then
17031 -- Prev is a private subtype or a derived type, and needs
17034 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
17037 elsif Ekind (Prev) = E_Private_Type
17038 and then Nkind_In (N, N_Task_Type_Declaration,
17039 N_Protected_Type_Declaration)
17042 ("completion of nonlimited type cannot be limited", N);
17044 elsif Ekind (Prev) = E_Record_Type_With_Private
17045 and then Nkind_In (N, N_Task_Type_Declaration,
17046 N_Protected_Type_Declaration)
17048 if not Is_Limited_Record (Prev) then
17050 ("completion of nonlimited type cannot be limited", N);
17052 elsif No (Interface_List (N)) then
17054 ("completion of tagged private type must be tagged",
17059 -- Ada 2005 (AI-251): Private extension declaration of a task
17060 -- type or a protected type. This case arises when covering
17061 -- interface types.
17063 elsif Nkind_In (N, N_Task_Type_Declaration,
17064 N_Protected_Type_Declaration)
17068 elsif Nkind (N) /= N_Full_Type_Declaration
17069 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
17072 ("full view of private extension must be an extension", N);
17074 elsif not (Abstract_Present (Parent (Prev)))
17075 and then Abstract_Present (Type_Definition (N))
17078 ("full view of non-abstract extension cannot be abstract", N);
17081 if not In_Private_Part (Current_Scope) then
17083 ("declaration of full view must appear in private part", N);
17086 if Ada_Version >= Ada_2012 then
17087 Check_Duplicate_Aspects;
17090 Copy_And_Swap (Prev, Id);
17091 Set_Has_Private_Declaration (Prev);
17092 Set_Has_Private_Declaration (Id);
17094 -- AI12-0133: Indicate whether we have a partial view with
17095 -- unknown discriminants, in which case initialization of objects
17096 -- of the type do not receive an invariant check.
17098 Set_Partial_View_Has_Unknown_Discr
17099 (Prev, Has_Unknown_Discriminants (Id));
17101 -- Preserve aspect and iterator flags that may have been set on
17102 -- the partial view.
17104 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
17105 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
17107 -- If no error, propagate freeze_node from private to full view.
17108 -- It may have been generated for an early operational item.
17110 if Present (Freeze_Node (Id))
17111 and then Serious_Errors_Detected = 0
17112 and then No (Full_View (Id))
17114 Set_Freeze_Node (Prev, Freeze_Node (Id));
17115 Set_Freeze_Node (Id, Empty);
17116 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
17119 Set_Full_View (Id, Prev);
17123 -- Verify that full declaration conforms to partial one
17125 if Is_Incomplete_Or_Private_Type (Prev)
17126 and then Present (Discriminant_Specifications (Prev_Par))
17128 if Present (Discriminant_Specifications (N)) then
17129 if Ekind (Prev) = E_Incomplete_Type then
17130 Check_Discriminant_Conformance (N, Prev, Prev);
17132 Check_Discriminant_Conformance (N, Prev, Id);
17137 ("missing discriminants in full type declaration", N);
17139 -- To avoid cascaded errors on subsequent use, share the
17140 -- discriminants of the partial view.
17142 Set_Discriminant_Specifications (N,
17143 Discriminant_Specifications (Prev_Par));
17147 -- A prior untagged partial view can have an associated class-wide
17148 -- type due to use of the class attribute, and in this case the full
17149 -- type must also be tagged. This Ada 95 usage is deprecated in favor
17150 -- of incomplete tagged declarations, but we check for it.
17153 and then (Is_Tagged_Type (Prev)
17154 or else Present (Class_Wide_Type (Prev)))
17156 -- Ada 2012 (AI05-0162): A private type may be the completion of
17157 -- an incomplete type.
17159 if Ada_Version >= Ada_2012
17160 and then Is_Incomplete_Type (Prev)
17161 and then Nkind_In (N, N_Private_Type_Declaration,
17162 N_Private_Extension_Declaration)
17164 -- No need to check private extensions since they are tagged
17166 if Nkind (N) = N_Private_Type_Declaration
17167 and then not Tagged_Present (N)
17172 -- The full declaration is either a tagged type (including
17173 -- a synchronized type that implements interfaces) or a
17174 -- type extension, otherwise this is an error.
17176 elsif Nkind_In (N, N_Task_Type_Declaration,
17177 N_Protected_Type_Declaration)
17179 if No (Interface_List (N)) and then not Error_Posted (N) then
17183 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
17185 -- Indicate that the previous declaration (tagged incomplete
17186 -- or private declaration) requires the same on the full one.
17188 if not Tagged_Present (Type_Definition (N)) then
17190 Set_Is_Tagged_Type (Id);
17193 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
17194 if No (Record_Extension_Part (Type_Definition (N))) then
17196 ("full declaration of } must be a record extension",
17199 -- Set some attributes to produce a usable full view
17201 Set_Is_Tagged_Type (Id);
17210 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
17211 and then Present (Premature_Use (Parent (Prev)))
17213 Error_Msg_Sloc := Sloc (N);
17215 ("\full declaration #", Premature_Use (Parent (Prev)));
17220 end Find_Type_Name;
17222 -------------------------
17223 -- Find_Type_Of_Object --
17224 -------------------------
17226 function Find_Type_Of_Object
17227 (Obj_Def : Node_Id;
17228 Related_Nod : Node_Id) return Entity_Id
17230 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
17231 P : Node_Id := Parent (Obj_Def);
17236 -- If the parent is a component_definition node we climb to the
17237 -- component_declaration node
17239 if Nkind (P) = N_Component_Definition then
17243 -- Case of an anonymous array subtype
17245 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
17246 N_Unconstrained_Array_Definition)
17249 Array_Type_Declaration (T, Obj_Def);
17251 -- Create an explicit subtype whenever possible
17253 elsif Nkind (P) /= N_Component_Declaration
17254 and then Def_Kind = N_Subtype_Indication
17256 -- Base name of subtype on object name, which will be unique in
17257 -- the current scope.
17259 -- If this is a duplicate declaration, return base type, to avoid
17260 -- generating duplicate anonymous types.
17262 if Error_Posted (P) then
17263 Analyze (Subtype_Mark (Obj_Def));
17264 return Entity (Subtype_Mark (Obj_Def));
17269 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
17271 T := Make_Defining_Identifier (Sloc (P), Nam);
17273 Insert_Action (Obj_Def,
17274 Make_Subtype_Declaration (Sloc (P),
17275 Defining_Identifier => T,
17276 Subtype_Indication => Relocate_Node (Obj_Def)));
17278 -- This subtype may need freezing, and this will not be done
17279 -- automatically if the object declaration is not in declarative
17280 -- part. Since this is an object declaration, the type cannot always
17281 -- be frozen here. Deferred constants do not freeze their type
17282 -- (which often enough will be private).
17284 if Nkind (P) = N_Object_Declaration
17285 and then Constant_Present (P)
17286 and then No (Expression (P))
17290 -- Here we freeze the base type of object type to catch premature use
17291 -- of discriminated private type without a full view.
17294 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
17297 -- Ada 2005 AI-406: the object definition in an object declaration
17298 -- can be an access definition.
17300 elsif Def_Kind = N_Access_Definition then
17301 T := Access_Definition (Related_Nod, Obj_Def);
17303 Set_Is_Local_Anonymous_Access
17305 V => (Ada_Version < Ada_2012)
17306 or else (Nkind (P) /= N_Object_Declaration)
17307 or else Is_Library_Level_Entity (Defining_Identifier (P)));
17309 -- Otherwise, the object definition is just a subtype_mark
17312 T := Process_Subtype (Obj_Def, Related_Nod);
17314 -- If expansion is disabled an object definition that is an aggregate
17315 -- will not get expanded and may lead to scoping problems in the back
17316 -- end, if the object is referenced in an inner scope. In that case
17317 -- create an itype reference for the object definition now. This
17318 -- may be redundant in some cases, but harmless.
17321 and then Nkind (Related_Nod) = N_Object_Declaration
17324 Build_Itype_Reference (T, Related_Nod);
17329 end Find_Type_Of_Object;
17331 --------------------------------
17332 -- Find_Type_Of_Subtype_Indic --
17333 --------------------------------
17335 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
17339 -- Case of subtype mark with a constraint
17341 if Nkind (S) = N_Subtype_Indication then
17342 Find_Type (Subtype_Mark (S));
17343 Typ := Entity (Subtype_Mark (S));
17346 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17349 ("incorrect constraint for this kind of type", Constraint (S));
17350 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17353 -- Otherwise we have a subtype mark without a constraint
17355 elsif Error_Posted (S) then
17356 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17364 -- Check No_Wide_Characters restriction
17366 Check_Wide_Character_Restriction (Typ, S);
17369 end Find_Type_Of_Subtype_Indic;
17371 -------------------------------------
17372 -- Floating_Point_Type_Declaration --
17373 -------------------------------------
17375 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17376 Digs : constant Node_Id := Digits_Expression (Def);
17377 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17379 Base_Typ : Entity_Id;
17380 Implicit_Base : Entity_Id;
17383 function Can_Derive_From (E : Entity_Id) return Boolean;
17384 -- Find if given digits value, and possibly a specified range, allows
17385 -- derivation from specified type
17387 function Find_Base_Type return Entity_Id;
17388 -- Find a predefined base type that Def can derive from, or generate
17389 -- an error and substitute Long_Long_Float if none exists.
17391 ---------------------
17392 -- Can_Derive_From --
17393 ---------------------
17395 function Can_Derive_From (E : Entity_Id) return Boolean is
17396 Spec : constant Entity_Id := Real_Range_Specification (Def);
17399 -- Check specified "digits" constraint
17401 if Digs_Val > Digits_Value (E) then
17405 -- Check for matching range, if specified
17407 if Present (Spec) then
17408 if Expr_Value_R (Type_Low_Bound (E)) >
17409 Expr_Value_R (Low_Bound (Spec))
17414 if Expr_Value_R (Type_High_Bound (E)) <
17415 Expr_Value_R (High_Bound (Spec))
17422 end Can_Derive_From;
17424 --------------------
17425 -- Find_Base_Type --
17426 --------------------
17428 function Find_Base_Type return Entity_Id is
17429 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17432 -- Iterate over the predefined types in order, returning the first
17433 -- one that Def can derive from.
17435 while Present (Choice) loop
17436 if Can_Derive_From (Node (Choice)) then
17437 return Node (Choice);
17440 Next_Elmt (Choice);
17443 -- If we can't derive from any existing type, use Long_Long_Float
17444 -- and give appropriate message explaining the problem.
17446 if Digs_Val > Max_Digs_Val then
17447 -- It might be the case that there is a type with the requested
17448 -- range, just not the combination of digits and range.
17451 ("no predefined type has requested range and precision",
17452 Real_Range_Specification (Def));
17456 ("range too large for any predefined type",
17457 Real_Range_Specification (Def));
17460 return Standard_Long_Long_Float;
17461 end Find_Base_Type;
17463 -- Start of processing for Floating_Point_Type_Declaration
17466 Check_Restriction (No_Floating_Point, Def);
17468 -- Create an implicit base type
17471 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17473 -- Analyze and verify digits value
17475 Analyze_And_Resolve (Digs, Any_Integer);
17476 Check_Digits_Expression (Digs);
17477 Digs_Val := Expr_Value (Digs);
17479 -- Process possible range spec and find correct type to derive from
17481 Process_Real_Range_Specification (Def);
17483 -- Check that requested number of digits is not too high.
17485 if Digs_Val > Max_Digs_Val then
17487 -- The check for Max_Base_Digits may be somewhat expensive, as it
17488 -- requires reading System, so only do it when necessary.
17491 Max_Base_Digits : constant Uint :=
17494 (Parent (RTE (RE_Max_Base_Digits))));
17497 if Digs_Val > Max_Base_Digits then
17498 Error_Msg_Uint_1 := Max_Base_Digits;
17499 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17501 elsif No (Real_Range_Specification (Def)) then
17502 Error_Msg_Uint_1 := Max_Digs_Val;
17503 Error_Msg_N ("types with more than ^ digits need range spec "
17504 & "(RM 3.5.7(6))", Digs);
17509 -- Find a suitable type to derive from or complain and use a substitute
17511 Base_Typ := Find_Base_Type;
17513 -- If there are bounds given in the declaration use them as the bounds
17514 -- of the type, otherwise use the bounds of the predefined base type
17515 -- that was chosen based on the Digits value.
17517 if Present (Real_Range_Specification (Def)) then
17518 Set_Scalar_Range (T, Real_Range_Specification (Def));
17519 Set_Is_Constrained (T);
17521 -- The bounds of this range must be converted to machine numbers
17522 -- in accordance with RM 4.9(38).
17524 Bound := Type_Low_Bound (T);
17526 if Nkind (Bound) = N_Real_Literal then
17528 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17529 Set_Is_Machine_Number (Bound);
17532 Bound := Type_High_Bound (T);
17534 if Nkind (Bound) = N_Real_Literal then
17536 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17537 Set_Is_Machine_Number (Bound);
17541 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17544 -- Complete definition of implicit base and declared first subtype. The
17545 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17546 -- are not clobbered when the floating point type acts as a full view of
17549 Set_Etype (Implicit_Base, Base_Typ);
17550 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17551 Set_Size_Info (Implicit_Base, Base_Typ);
17552 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17553 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17554 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17555 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17557 Set_Ekind (T, E_Floating_Point_Subtype);
17558 Set_Etype (T, Implicit_Base);
17559 Set_Size_Info (T, Implicit_Base);
17560 Set_RM_Size (T, RM_Size (Implicit_Base));
17561 Inherit_Rep_Item_Chain (T, Implicit_Base);
17562 Set_Digits_Value (T, Digs_Val);
17563 end Floating_Point_Type_Declaration;
17565 ----------------------------
17566 -- Get_Discriminant_Value --
17567 ----------------------------
17569 -- This is the situation:
17571 -- There is a non-derived type
17573 -- type T0 (Dx, Dy, Dz...)
17575 -- There are zero or more levels of derivation, with each derivation
17576 -- either purely inheriting the discriminants, or defining its own.
17578 -- type Ti is new Ti-1
17580 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17582 -- subtype Ti is ...
17584 -- The subtype issue is avoided by the use of Original_Record_Component,
17585 -- and the fact that derived subtypes also derive the constraints.
17587 -- This chain leads back from
17589 -- Typ_For_Constraint
17591 -- Typ_For_Constraint has discriminants, and the value for each
17592 -- discriminant is given by its corresponding Elmt of Constraints.
17594 -- Discriminant is some discriminant in this hierarchy
17596 -- We need to return its value
17598 -- We do this by recursively searching each level, and looking for
17599 -- Discriminant. Once we get to the bottom, we start backing up
17600 -- returning the value for it which may in turn be a discriminant
17601 -- further up, so on the backup we continue the substitution.
17603 function Get_Discriminant_Value
17604 (Discriminant : Entity_Id;
17605 Typ_For_Constraint : Entity_Id;
17606 Constraint : Elist_Id) return Node_Id
17608 function Root_Corresponding_Discriminant
17609 (Discr : Entity_Id) return Entity_Id;
17610 -- Given a discriminant, traverse the chain of inherited discriminants
17611 -- and return the topmost discriminant.
17613 function Search_Derivation_Levels
17615 Discrim_Values : Elist_Id;
17616 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17617 -- This is the routine that performs the recursive search of levels
17618 -- as described above.
17620 -------------------------------------
17621 -- Root_Corresponding_Discriminant --
17622 -------------------------------------
17624 function Root_Corresponding_Discriminant
17625 (Discr : Entity_Id) return Entity_Id
17631 while Present (Corresponding_Discriminant (D)) loop
17632 D := Corresponding_Discriminant (D);
17636 end Root_Corresponding_Discriminant;
17638 ------------------------------
17639 -- Search_Derivation_Levels --
17640 ------------------------------
17642 function Search_Derivation_Levels
17644 Discrim_Values : Elist_Id;
17645 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17649 Result : Node_Or_Entity_Id;
17650 Result_Entity : Node_Id;
17653 -- If inappropriate type, return Error, this happens only in
17654 -- cascaded error situations, and we want to avoid a blow up.
17656 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17660 -- Look deeper if possible. Use Stored_Constraints only for
17661 -- untagged types. For tagged types use the given constraint.
17662 -- This asymmetry needs explanation???
17664 if not Stored_Discrim_Values
17665 and then Present (Stored_Constraint (Ti))
17666 and then not Is_Tagged_Type (Ti)
17669 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17672 Td : constant Entity_Id := Etype (Ti);
17676 Result := Discriminant;
17679 if Present (Stored_Constraint (Ti)) then
17681 Search_Derivation_Levels
17682 (Td, Stored_Constraint (Ti), True);
17685 Search_Derivation_Levels
17686 (Td, Discrim_Values, Stored_Discrim_Values);
17692 -- Extra underlying places to search, if not found above. For
17693 -- concurrent types, the relevant discriminant appears in the
17694 -- corresponding record. For a type derived from a private type
17695 -- without discriminant, the full view inherits the discriminants
17696 -- of the full view of the parent.
17698 if Result = Discriminant then
17699 if Is_Concurrent_Type (Ti)
17700 and then Present (Corresponding_Record_Type (Ti))
17703 Search_Derivation_Levels (
17704 Corresponding_Record_Type (Ti),
17706 Stored_Discrim_Values);
17708 elsif Is_Private_Type (Ti)
17709 and then not Has_Discriminants (Ti)
17710 and then Present (Full_View (Ti))
17711 and then Etype (Full_View (Ti)) /= Ti
17714 Search_Derivation_Levels (
17717 Stored_Discrim_Values);
17721 -- If Result is not a (reference to a) discriminant, return it,
17722 -- otherwise set Result_Entity to the discriminant.
17724 if Nkind (Result) = N_Defining_Identifier then
17725 pragma Assert (Result = Discriminant);
17726 Result_Entity := Result;
17729 if not Denotes_Discriminant (Result) then
17733 Result_Entity := Entity (Result);
17736 -- See if this level of derivation actually has discriminants because
17737 -- tagged derivations can add them, hence the lower levels need not
17740 if not Has_Discriminants (Ti) then
17744 -- Scan Ti's discriminants for Result_Entity, and return its
17745 -- corresponding value, if any.
17747 Result_Entity := Original_Record_Component (Result_Entity);
17749 Assoc := First_Elmt (Discrim_Values);
17751 if Stored_Discrim_Values then
17752 Disc := First_Stored_Discriminant (Ti);
17754 Disc := First_Discriminant (Ti);
17757 while Present (Disc) loop
17759 -- If no further associations return the discriminant, value will
17760 -- be found on the second pass.
17766 if Original_Record_Component (Disc) = Result_Entity then
17767 return Node (Assoc);
17772 if Stored_Discrim_Values then
17773 Next_Stored_Discriminant (Disc);
17775 Next_Discriminant (Disc);
17779 -- Could not find it
17782 end Search_Derivation_Levels;
17786 Result : Node_Or_Entity_Id;
17788 -- Start of processing for Get_Discriminant_Value
17791 -- ??? This routine is a gigantic mess and will be deleted. For the
17792 -- time being just test for the trivial case before calling recurse.
17794 -- We are now celebrating the 20th anniversary of this comment!
17796 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17802 D := First_Discriminant (Typ_For_Constraint);
17803 E := First_Elmt (Constraint);
17804 while Present (D) loop
17805 if Chars (D) = Chars (Discriminant) then
17809 Next_Discriminant (D);
17815 Result := Search_Derivation_Levels
17816 (Typ_For_Constraint, Constraint, False);
17818 -- ??? hack to disappear when this routine is gone
17820 if Nkind (Result) = N_Defining_Identifier then
17826 D := First_Discriminant (Typ_For_Constraint);
17827 E := First_Elmt (Constraint);
17828 while Present (D) loop
17829 if Root_Corresponding_Discriminant (D) = Discriminant then
17833 Next_Discriminant (D);
17839 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17841 end Get_Discriminant_Value;
17843 --------------------------
17844 -- Has_Range_Constraint --
17845 --------------------------
17847 function Has_Range_Constraint (N : Node_Id) return Boolean is
17848 C : constant Node_Id := Constraint (N);
17851 if Nkind (C) = N_Range_Constraint then
17854 elsif Nkind (C) = N_Digits_Constraint then
17856 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17857 or else Present (Range_Constraint (C));
17859 elsif Nkind (C) = N_Delta_Constraint then
17860 return Present (Range_Constraint (C));
17865 end Has_Range_Constraint;
17867 ------------------------
17868 -- Inherit_Components --
17869 ------------------------
17871 function Inherit_Components
17873 Parent_Base : Entity_Id;
17874 Derived_Base : Entity_Id;
17875 Is_Tagged : Boolean;
17876 Inherit_Discr : Boolean;
17877 Discs : Elist_Id) return Elist_Id
17879 Assoc_List : constant Elist_Id := New_Elmt_List;
17881 procedure Inherit_Component
17882 (Old_C : Entity_Id;
17883 Plain_Discrim : Boolean := False;
17884 Stored_Discrim : Boolean := False);
17885 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17886 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17887 -- True, Old_C is a stored discriminant. If they are both false then
17888 -- Old_C is a regular component.
17890 -----------------------
17891 -- Inherit_Component --
17892 -----------------------
17894 procedure Inherit_Component
17895 (Old_C : Entity_Id;
17896 Plain_Discrim : Boolean := False;
17897 Stored_Discrim : Boolean := False)
17899 procedure Set_Anonymous_Type (Id : Entity_Id);
17900 -- Id denotes the entity of an access discriminant or anonymous
17901 -- access component. Set the type of Id to either the same type of
17902 -- Old_C or create a new one depending on whether the parent and
17903 -- the child types are in the same scope.
17905 ------------------------
17906 -- Set_Anonymous_Type --
17907 ------------------------
17909 procedure Set_Anonymous_Type (Id : Entity_Id) is
17910 Old_Typ : constant Entity_Id := Etype (Old_C);
17913 if Scope (Parent_Base) = Scope (Derived_Base) then
17914 Set_Etype (Id, Old_Typ);
17916 -- The parent and the derived type are in two different scopes.
17917 -- Reuse the type of the original discriminant / component by
17918 -- copying it in order to preserve all attributes.
17922 Typ : constant Entity_Id := New_Copy (Old_Typ);
17925 Set_Etype (Id, Typ);
17927 -- Since we do not generate component declarations for
17928 -- inherited components, associate the itype with the
17931 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17932 Set_Scope (Typ, Derived_Base);
17935 end Set_Anonymous_Type;
17937 -- Local variables and constants
17939 New_C : constant Entity_Id := New_Copy (Old_C);
17941 Corr_Discrim : Entity_Id;
17942 Discrim : Entity_Id;
17944 -- Start of processing for Inherit_Component
17947 pragma Assert (not Is_Tagged or not Stored_Discrim);
17949 Set_Parent (New_C, Parent (Old_C));
17951 -- Regular discriminants and components must be inserted in the scope
17952 -- of the Derived_Base. Do it here.
17954 if not Stored_Discrim then
17955 Enter_Name (New_C);
17958 -- For tagged types the Original_Record_Component must point to
17959 -- whatever this field was pointing to in the parent type. This has
17960 -- already been achieved by the call to New_Copy above.
17962 if not Is_Tagged then
17963 Set_Original_Record_Component (New_C, New_C);
17966 -- Set the proper type of an access discriminant
17968 if Ekind (New_C) = E_Discriminant
17969 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17971 Set_Anonymous_Type (New_C);
17974 -- If we have inherited a component then see if its Etype contains
17975 -- references to Parent_Base discriminants. In this case, replace
17976 -- these references with the constraints given in Discs. We do not
17977 -- do this for the partial view of private types because this is
17978 -- not needed (only the components of the full view will be used
17979 -- for code generation) and cause problem. We also avoid this
17980 -- transformation in some error situations.
17982 if Ekind (New_C) = E_Component then
17984 -- Set the proper type of an anonymous access component
17986 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17987 Set_Anonymous_Type (New_C);
17989 elsif (Is_Private_Type (Derived_Base)
17990 and then not Is_Generic_Type (Derived_Base))
17991 or else (Is_Empty_Elmt_List (Discs)
17992 and then not Expander_Active)
17994 Set_Etype (New_C, Etype (Old_C));
17997 -- The current component introduces a circularity of the
18000 -- limited with Pack_2;
18001 -- package Pack_1 is
18002 -- type T_1 is tagged record
18003 -- Comp : access Pack_2.T_2;
18009 -- package Pack_2 is
18010 -- type T_2 is new Pack_1.T_1 with ...;
18015 Constrain_Component_Type
18016 (Old_C, Derived_Base, N, Parent_Base, Discs));
18020 -- In derived tagged types it is illegal to reference a non
18021 -- discriminant component in the parent type. To catch this, mark
18022 -- these components with an Ekind of E_Void. This will be reset in
18023 -- Record_Type_Definition after processing the record extension of
18024 -- the derived type.
18026 -- If the declaration is a private extension, there is no further
18027 -- record extension to process, and the components retain their
18028 -- current kind, because they are visible at this point.
18030 if Is_Tagged and then Ekind (New_C) = E_Component
18031 and then Nkind (N) /= N_Private_Extension_Declaration
18033 Set_Ekind (New_C, E_Void);
18036 if Plain_Discrim then
18037 Set_Corresponding_Discriminant (New_C, Old_C);
18038 Build_Discriminal (New_C);
18040 -- If we are explicitly inheriting a stored discriminant it will be
18041 -- completely hidden.
18043 elsif Stored_Discrim then
18044 Set_Corresponding_Discriminant (New_C, Empty);
18045 Set_Discriminal (New_C, Empty);
18046 Set_Is_Completely_Hidden (New_C);
18048 -- Set the Original_Record_Component of each discriminant in the
18049 -- derived base to point to the corresponding stored that we just
18052 Discrim := First_Discriminant (Derived_Base);
18053 while Present (Discrim) loop
18054 Corr_Discrim := Corresponding_Discriminant (Discrim);
18056 -- Corr_Discrim could be missing in an error situation
18058 if Present (Corr_Discrim)
18059 and then Original_Record_Component (Corr_Discrim) = Old_C
18061 Set_Original_Record_Component (Discrim, New_C);
18064 Next_Discriminant (Discrim);
18067 Append_Entity (New_C, Derived_Base);
18070 if not Is_Tagged then
18071 Append_Elmt (Old_C, Assoc_List);
18072 Append_Elmt (New_C, Assoc_List);
18074 end Inherit_Component;
18076 -- Variables local to Inherit_Component
18078 Loc : constant Source_Ptr := Sloc (N);
18080 Parent_Discrim : Entity_Id;
18081 Stored_Discrim : Entity_Id;
18083 Component : Entity_Id;
18085 -- Start of processing for Inherit_Components
18088 if not Is_Tagged then
18089 Append_Elmt (Parent_Base, Assoc_List);
18090 Append_Elmt (Derived_Base, Assoc_List);
18093 -- Inherit parent discriminants if needed
18095 if Inherit_Discr then
18096 Parent_Discrim := First_Discriminant (Parent_Base);
18097 while Present (Parent_Discrim) loop
18098 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
18099 Next_Discriminant (Parent_Discrim);
18103 -- Create explicit stored discrims for untagged types when necessary
18105 if not Has_Unknown_Discriminants (Derived_Base)
18106 and then Has_Discriminants (Parent_Base)
18107 and then not Is_Tagged
18110 or else First_Discriminant (Parent_Base) /=
18111 First_Stored_Discriminant (Parent_Base))
18113 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
18114 while Present (Stored_Discrim) loop
18115 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
18116 Next_Stored_Discriminant (Stored_Discrim);
18120 -- See if we can apply the second transformation for derived types, as
18121 -- explained in point 6. in the comments above Build_Derived_Record_Type
18122 -- This is achieved by appending Derived_Base discriminants into Discs,
18123 -- which has the side effect of returning a non empty Discs list to the
18124 -- caller of Inherit_Components, which is what we want. This must be
18125 -- done for private derived types if there are explicit stored
18126 -- discriminants, to ensure that we can retrieve the values of the
18127 -- constraints provided in the ancestors.
18130 and then Is_Empty_Elmt_List (Discs)
18131 and then Present (First_Discriminant (Derived_Base))
18133 (not Is_Private_Type (Derived_Base)
18134 or else Is_Completely_Hidden
18135 (First_Stored_Discriminant (Derived_Base))
18136 or else Is_Generic_Type (Derived_Base))
18138 D := First_Discriminant (Derived_Base);
18139 while Present (D) loop
18140 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
18141 Next_Discriminant (D);
18145 -- Finally, inherit non-discriminant components unless they are not
18146 -- visible because defined or inherited from the full view of the
18147 -- parent. Don't inherit the _parent field of the parent type.
18149 Component := First_Entity (Parent_Base);
18150 while Present (Component) loop
18152 -- Ada 2005 (AI-251): Do not inherit components associated with
18153 -- secondary tags of the parent.
18155 if Ekind (Component) = E_Component
18156 and then Present (Related_Type (Component))
18160 elsif Ekind (Component) /= E_Component
18161 or else Chars (Component) = Name_uParent
18165 -- If the derived type is within the parent type's declarative
18166 -- region, then the components can still be inherited even though
18167 -- they aren't visible at this point. This can occur for cases
18168 -- such as within public child units where the components must
18169 -- become visible upon entering the child unit's private part.
18171 elsif not Is_Visible_Component (Component)
18172 and then not In_Open_Scopes (Scope (Parent_Base))
18176 elsif Ekind_In (Derived_Base, E_Private_Type,
18177 E_Limited_Private_Type)
18182 Inherit_Component (Component);
18185 Next_Entity (Component);
18188 -- For tagged derived types, inherited discriminants cannot be used in
18189 -- component declarations of the record extension part. To achieve this
18190 -- we mark the inherited discriminants as not visible.
18192 if Is_Tagged and then Inherit_Discr then
18193 D := First_Discriminant (Derived_Base);
18194 while Present (D) loop
18195 Set_Is_Immediately_Visible (D, False);
18196 Next_Discriminant (D);
18201 end Inherit_Components;
18203 -----------------------------
18204 -- Inherit_Predicate_Flags --
18205 -----------------------------
18207 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
18209 Set_Has_Predicates (Subt, Has_Predicates (Par));
18210 Set_Has_Static_Predicate_Aspect
18211 (Subt, Has_Static_Predicate_Aspect (Par));
18212 Set_Has_Dynamic_Predicate_Aspect
18213 (Subt, Has_Dynamic_Predicate_Aspect (Par));
18214 end Inherit_Predicate_Flags;
18216 ----------------------
18217 -- Is_EVF_Procedure --
18218 ----------------------
18220 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
18221 Formal : Entity_Id;
18224 -- Examine the formals of an Extensions_Visible False procedure looking
18225 -- for a controlling OUT parameter.
18227 if Ekind (Subp) = E_Procedure
18228 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
18230 Formal := First_Formal (Subp);
18231 while Present (Formal) loop
18232 if Ekind (Formal) = E_Out_Parameter
18233 and then Is_Controlling_Formal (Formal)
18238 Next_Formal (Formal);
18243 end Is_EVF_Procedure;
18245 -----------------------
18246 -- Is_Null_Extension --
18247 -----------------------
18249 function Is_Null_Extension (T : Entity_Id) return Boolean is
18250 Type_Decl : constant Node_Id := Parent (Base_Type (T));
18251 Comp_List : Node_Id;
18255 if Nkind (Type_Decl) /= N_Full_Type_Declaration
18256 or else not Is_Tagged_Type (T)
18257 or else Nkind (Type_Definition (Type_Decl)) /=
18258 N_Derived_Type_Definition
18259 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
18265 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
18267 if Present (Discriminant_Specifications (Type_Decl)) then
18270 elsif Present (Comp_List)
18271 and then Is_Non_Empty_List (Component_Items (Comp_List))
18273 Comp := First (Component_Items (Comp_List));
18275 -- Only user-defined components are relevant. The component list
18276 -- may also contain a parent component and internal components
18277 -- corresponding to secondary tags, but these do not determine
18278 -- whether this is a null extension.
18280 while Present (Comp) loop
18281 if Comes_From_Source (Comp) then
18293 end Is_Null_Extension;
18295 ------------------------------
18296 -- Is_Valid_Constraint_Kind --
18297 ------------------------------
18299 function Is_Valid_Constraint_Kind
18300 (T_Kind : Type_Kind;
18301 Constraint_Kind : Node_Kind) return Boolean
18305 when Enumeration_Kind
18308 return Constraint_Kind = N_Range_Constraint;
18310 when Decimal_Fixed_Point_Kind =>
18311 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18312 N_Range_Constraint);
18314 when Ordinary_Fixed_Point_Kind =>
18315 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
18316 N_Range_Constraint);
18319 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18320 N_Range_Constraint);
18327 | E_Incomplete_Type
18331 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
18334 return True; -- Error will be detected later
18336 end Is_Valid_Constraint_Kind;
18338 --------------------------
18339 -- Is_Visible_Component --
18340 --------------------------
18342 function Is_Visible_Component
18344 N : Node_Id := Empty) return Boolean
18346 Original_Comp : Entity_Id := Empty;
18347 Original_Type : Entity_Id;
18348 Type_Scope : Entity_Id;
18350 function Is_Local_Type (Typ : Entity_Id) return Boolean;
18351 -- Check whether parent type of inherited component is declared locally,
18352 -- possibly within a nested package or instance. The current scope is
18353 -- the derived record itself.
18355 -------------------
18356 -- Is_Local_Type --
18357 -------------------
18359 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18363 Scop := Scope (Typ);
18364 while Present (Scop)
18365 and then Scop /= Standard_Standard
18367 if Scop = Scope (Current_Scope) then
18371 Scop := Scope (Scop);
18377 -- Start of processing for Is_Visible_Component
18380 if Ekind_In (C, E_Component, E_Discriminant) then
18381 Original_Comp := Original_Record_Component (C);
18384 if No (Original_Comp) then
18386 -- Premature usage, or previous error
18391 Original_Type := Scope (Original_Comp);
18392 Type_Scope := Scope (Base_Type (Scope (C)));
18395 -- This test only concerns tagged types
18397 if not Is_Tagged_Type (Original_Type) then
18400 -- If it is _Parent or _Tag, there is no visibility issue
18402 elsif not Comes_From_Source (Original_Comp) then
18405 -- Discriminants are visible unless the (private) type has unknown
18406 -- discriminants. If the discriminant reference is inserted for a
18407 -- discriminant check on a full view it is also visible.
18409 elsif Ekind (Original_Comp) = E_Discriminant
18411 (not Has_Unknown_Discriminants (Original_Type)
18412 or else (Present (N)
18413 and then Nkind (N) = N_Selected_Component
18414 and then Nkind (Prefix (N)) = N_Type_Conversion
18415 and then not Comes_From_Source (Prefix (N))))
18419 -- In the body of an instantiation, check the visibility of a component
18420 -- in case it has a homograph that is a primitive operation of a private
18421 -- type which was not visible in the generic unit.
18423 -- Should Is_Prefixed_Call be propagated from template to instance???
18425 elsif In_Instance_Body then
18426 if not Is_Tagged_Type (Original_Type)
18427 or else not Is_Private_Type (Original_Type)
18433 Subp_Elmt : Elmt_Id;
18436 Subp_Elmt := First_Elmt (Primitive_Operations (Original_Type));
18437 while Present (Subp_Elmt) loop
18439 -- The component is hidden by a primitive operation
18441 if Chars (Node (Subp_Elmt)) = Chars (C) then
18445 Next_Elmt (Subp_Elmt);
18452 -- If the component has been declared in an ancestor which is currently
18453 -- a private type, then it is not visible. The same applies if the
18454 -- component's containing type is not in an open scope and the original
18455 -- component's enclosing type is a visible full view of a private type
18456 -- (which can occur in cases where an attempt is being made to reference
18457 -- a component in a sibling package that is inherited from a visible
18458 -- component of a type in an ancestor package; the component in the
18459 -- sibling package should not be visible even though the component it
18460 -- inherited from is visible). This does not apply however in the case
18461 -- where the scope of the type is a private child unit, or when the
18462 -- parent comes from a local package in which the ancestor is currently
18463 -- visible. The latter suppression of visibility is needed for cases
18464 -- that are tested in B730006.
18466 elsif Is_Private_Type (Original_Type)
18468 (not Is_Private_Descendant (Type_Scope)
18469 and then not In_Open_Scopes (Type_Scope)
18470 and then Has_Private_Declaration (Original_Type))
18472 -- If the type derives from an entity in a formal package, there
18473 -- are no additional visible components.
18475 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18476 N_Formal_Package_Declaration
18480 -- if we are not in the private part of the current package, there
18481 -- are no additional visible components.
18483 elsif Ekind (Scope (Current_Scope)) = E_Package
18484 and then not In_Private_Part (Scope (Current_Scope))
18489 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18490 and then In_Open_Scopes (Scope (Original_Type))
18491 and then Is_Local_Type (Type_Scope);
18494 -- There is another weird way in which a component may be invisible when
18495 -- the private and the full view are not derived from the same ancestor.
18496 -- Here is an example :
18498 -- type A1 is tagged record F1 : integer; end record;
18499 -- type A2 is new A1 with record F2 : integer; end record;
18500 -- type T is new A1 with private;
18502 -- type T is new A2 with null record;
18504 -- In this case, the full view of T inherits F1 and F2 but the private
18505 -- view inherits only F1
18509 Ancestor : Entity_Id := Scope (C);
18513 if Ancestor = Original_Type then
18516 -- The ancestor may have a partial view of the original type,
18517 -- but if the full view is in scope, as in a child body, the
18518 -- component is visible.
18520 elsif In_Private_Part (Scope (Original_Type))
18521 and then Full_View (Ancestor) = Original_Type
18525 elsif Ancestor = Etype (Ancestor) then
18527 -- No further ancestors to examine
18532 Ancestor := Etype (Ancestor);
18536 end Is_Visible_Component;
18538 --------------------------
18539 -- Make_Class_Wide_Type --
18540 --------------------------
18542 procedure Make_Class_Wide_Type (T : Entity_Id) is
18543 CW_Type : Entity_Id;
18545 Next_E : Entity_Id;
18548 if Present (Class_Wide_Type (T)) then
18550 -- The class-wide type is a partially decorated entity created for a
18551 -- unanalyzed tagged type referenced through a limited with clause.
18552 -- When the tagged type is analyzed, its class-wide type needs to be
18553 -- redecorated. Note that we reuse the entity created by Decorate_
18554 -- Tagged_Type in order to preserve all links.
18556 if Materialize_Entity (Class_Wide_Type (T)) then
18557 CW_Type := Class_Wide_Type (T);
18558 Set_Materialize_Entity (CW_Type, False);
18560 -- The class wide type can have been defined by the partial view, in
18561 -- which case everything is already done.
18567 -- Default case, we need to create a new class-wide type
18571 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18574 -- Inherit root type characteristics
18576 CW_Name := Chars (CW_Type);
18577 Next_E := Next_Entity (CW_Type);
18578 Copy_Node (T, CW_Type);
18579 Set_Comes_From_Source (CW_Type, False);
18580 Set_Chars (CW_Type, CW_Name);
18581 Set_Parent (CW_Type, Parent (T));
18582 Set_Next_Entity (CW_Type, Next_E);
18584 -- Ensure we have a new freeze node for the class-wide type. The partial
18585 -- view may have freeze action of its own, requiring a proper freeze
18586 -- node, and the same freeze node cannot be shared between the two
18589 Set_Has_Delayed_Freeze (CW_Type);
18590 Set_Freeze_Node (CW_Type, Empty);
18592 -- Customize the class-wide type: It has no prim. op., it cannot be
18593 -- abstract, its Etype points back to the specific root type, and it
18594 -- cannot have any invariants.
18596 Set_Ekind (CW_Type, E_Class_Wide_Type);
18597 Set_Is_Tagged_Type (CW_Type, True);
18598 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18599 Set_Is_Abstract_Type (CW_Type, False);
18600 Set_Is_Constrained (CW_Type, False);
18601 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18602 Set_Default_SSO (CW_Type);
18603 Set_Has_Inheritable_Invariants (CW_Type, False);
18604 Set_Has_Inherited_Invariants (CW_Type, False);
18605 Set_Has_Own_Invariants (CW_Type, False);
18607 if Ekind (T) = E_Class_Wide_Subtype then
18608 Set_Etype (CW_Type, Etype (Base_Type (T)));
18610 Set_Etype (CW_Type, T);
18613 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18615 -- If this is the class_wide type of a constrained subtype, it does
18616 -- not have discriminants.
18618 Set_Has_Discriminants (CW_Type,
18619 Has_Discriminants (T) and then not Is_Constrained (T));
18621 Set_Has_Unknown_Discriminants (CW_Type, True);
18622 Set_Class_Wide_Type (T, CW_Type);
18623 Set_Equivalent_Type (CW_Type, Empty);
18625 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18627 Set_Class_Wide_Type (CW_Type, CW_Type);
18628 end Make_Class_Wide_Type;
18634 procedure Make_Index
18636 Related_Nod : Node_Id;
18637 Related_Id : Entity_Id := Empty;
18638 Suffix_Index : Nat := 1;
18639 In_Iter_Schm : Boolean := False)
18643 Def_Id : Entity_Id := Empty;
18644 Found : Boolean := False;
18647 -- For a discrete range used in a constrained array definition and
18648 -- defined by a range, an implicit conversion to the predefined type
18649 -- INTEGER is assumed if each bound is either a numeric literal, a named
18650 -- number, or an attribute, and the type of both bounds (prior to the
18651 -- implicit conversion) is the type universal_integer. Otherwise, both
18652 -- bounds must be of the same discrete type, other than universal
18653 -- integer; this type must be determinable independently of the
18654 -- context, but using the fact that the type must be discrete and that
18655 -- both bounds must have the same type.
18657 -- Character literals also have a universal type in the absence of
18658 -- of additional context, and are resolved to Standard_Character.
18660 if Nkind (N) = N_Range then
18662 -- The index is given by a range constraint. The bounds are known
18663 -- to be of a consistent type.
18665 if not Is_Overloaded (N) then
18668 -- For universal bounds, choose the specific predefined type
18670 if T = Universal_Integer then
18671 T := Standard_Integer;
18673 elsif T = Any_Character then
18674 Ambiguous_Character (Low_Bound (N));
18676 T := Standard_Character;
18679 -- The node may be overloaded because some user-defined operators
18680 -- are available, but if a universal interpretation exists it is
18681 -- also the selected one.
18683 elsif Universal_Interpretation (N) = Universal_Integer then
18684 T := Standard_Integer;
18690 Ind : Interp_Index;
18694 Get_First_Interp (N, Ind, It);
18695 while Present (It.Typ) loop
18696 if Is_Discrete_Type (It.Typ) then
18699 and then not Covers (It.Typ, T)
18700 and then not Covers (T, It.Typ)
18702 Error_Msg_N ("ambiguous bounds in discrete range", N);
18710 Get_Next_Interp (Ind, It);
18713 if T = Any_Type then
18714 Error_Msg_N ("discrete type required for range", N);
18715 Set_Etype (N, Any_Type);
18718 elsif T = Universal_Integer then
18719 T := Standard_Integer;
18724 if not Is_Discrete_Type (T) then
18725 Error_Msg_N ("discrete type required for range", N);
18726 Set_Etype (N, Any_Type);
18730 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18731 and then Attribute_Name (Low_Bound (N)) = Name_First
18732 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18733 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18734 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18736 -- The type of the index will be the type of the prefix, as long
18737 -- as the upper bound is 'Last of the same type.
18739 Def_Id := Entity (Prefix (Low_Bound (N)));
18741 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18742 or else Attribute_Name (High_Bound (N)) /= Name_Last
18743 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18744 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18751 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18753 elsif Nkind (N) = N_Subtype_Indication then
18755 -- The index is given by a subtype with a range constraint
18757 T := Base_Type (Entity (Subtype_Mark (N)));
18759 if not Is_Discrete_Type (T) then
18760 Error_Msg_N ("discrete type required for range", N);
18761 Set_Etype (N, Any_Type);
18765 R := Range_Expression (Constraint (N));
18768 Process_Range_Expr_In_Decl
18769 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18771 elsif Nkind (N) = N_Attribute_Reference then
18773 -- Catch beginner's error (use of attribute other than 'Range)
18775 if Attribute_Name (N) /= Name_Range then
18776 Error_Msg_N ("expect attribute ''Range", N);
18777 Set_Etype (N, Any_Type);
18781 -- If the node denotes the range of a type mark, that is also the
18782 -- resulting type, and we do not need to create an Itype for it.
18784 if Is_Entity_Name (Prefix (N))
18785 and then Comes_From_Source (N)
18786 and then Is_Type (Entity (Prefix (N)))
18787 and then Is_Discrete_Type (Entity (Prefix (N)))
18789 Def_Id := Entity (Prefix (N));
18792 Analyze_And_Resolve (N);
18796 -- If none of the above, must be a subtype. We convert this to a
18797 -- range attribute reference because in the case of declared first
18798 -- named subtypes, the types in the range reference can be different
18799 -- from the type of the entity. A range attribute normalizes the
18800 -- reference and obtains the correct types for the bounds.
18802 -- This transformation is in the nature of an expansion, is only
18803 -- done if expansion is active. In particular, it is not done on
18804 -- formal generic types, because we need to retain the name of the
18805 -- original index for instantiation purposes.
18808 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18809 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18810 Set_Etype (N, Any_Integer);
18814 -- The type mark may be that of an incomplete type. It is only
18815 -- now that we can get the full view, previous analysis does
18816 -- not look specifically for a type mark.
18818 Set_Entity (N, Get_Full_View (Entity (N)));
18819 Set_Etype (N, Entity (N));
18820 Def_Id := Entity (N);
18822 if not Is_Discrete_Type (Def_Id) then
18823 Error_Msg_N ("discrete type required for index", N);
18824 Set_Etype (N, Any_Type);
18829 if Expander_Active then
18831 Make_Attribute_Reference (Sloc (N),
18832 Attribute_Name => Name_Range,
18833 Prefix => Relocate_Node (N)));
18835 -- The original was a subtype mark that does not freeze. This
18836 -- means that the rewritten version must not freeze either.
18838 Set_Must_Not_Freeze (N);
18839 Set_Must_Not_Freeze (Prefix (N));
18840 Analyze_And_Resolve (N);
18844 -- If expander is inactive, type is legal, nothing else to construct
18851 if not Is_Discrete_Type (T) then
18852 Error_Msg_N ("discrete type required for range", N);
18853 Set_Etype (N, Any_Type);
18856 elsif T = Any_Type then
18857 Set_Etype (N, Any_Type);
18861 -- We will now create the appropriate Itype to describe the range, but
18862 -- first a check. If we originally had a subtype, then we just label
18863 -- the range with this subtype. Not only is there no need to construct
18864 -- a new subtype, but it is wrong to do so for two reasons:
18866 -- 1. A legality concern, if we have a subtype, it must not freeze,
18867 -- and the Itype would cause freezing incorrectly
18869 -- 2. An efficiency concern, if we created an Itype, it would not be
18870 -- recognized as the same type for the purposes of eliminating
18871 -- checks in some circumstances.
18873 -- We signal this case by setting the subtype entity in Def_Id
18875 if No (Def_Id) then
18877 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18878 Set_Etype (Def_Id, Base_Type (T));
18880 if Is_Signed_Integer_Type (T) then
18881 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18883 elsif Is_Modular_Integer_Type (T) then
18884 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18887 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18888 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18889 Set_First_Literal (Def_Id, First_Literal (T));
18892 Set_Size_Info (Def_Id, (T));
18893 Set_RM_Size (Def_Id, RM_Size (T));
18894 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18896 Set_Scalar_Range (Def_Id, R);
18897 Conditional_Delay (Def_Id, T);
18899 if Nkind (N) = N_Subtype_Indication then
18900 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18903 -- In the subtype indication case, if the immediate parent of the
18904 -- new subtype is non-static, then the subtype we create is non-
18905 -- static, even if its bounds are static.
18907 if Nkind (N) = N_Subtype_Indication
18908 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18910 Set_Is_Non_Static_Subtype (Def_Id);
18914 -- Final step is to label the index with this constructed type
18916 Set_Etype (N, Def_Id);
18919 ------------------------------
18920 -- Modular_Type_Declaration --
18921 ------------------------------
18923 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18924 Mod_Expr : constant Node_Id := Expression (Def);
18927 procedure Set_Modular_Size (Bits : Int);
18928 -- Sets RM_Size to Bits, and Esize to normal word size above this
18930 ----------------------
18931 -- Set_Modular_Size --
18932 ----------------------
18934 procedure Set_Modular_Size (Bits : Int) is
18936 Set_RM_Size (T, UI_From_Int (Bits));
18941 elsif Bits <= 16 then
18942 Init_Esize (T, 16);
18944 elsif Bits <= 32 then
18945 Init_Esize (T, 32);
18948 Init_Esize (T, System_Max_Binary_Modulus_Power);
18951 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18952 Set_Is_Known_Valid (T);
18954 end Set_Modular_Size;
18956 -- Start of processing for Modular_Type_Declaration
18959 -- If the mod expression is (exactly) 2 * literal, where literal is
18960 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18962 if Warn_On_Suspicious_Modulus_Value
18963 and then Nkind (Mod_Expr) = N_Op_Multiply
18964 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18965 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18966 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18967 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18970 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18973 -- Proceed with analysis of mod expression
18975 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18977 Set_Ekind (T, E_Modular_Integer_Type);
18978 Init_Alignment (T);
18979 Set_Is_Constrained (T);
18981 if not Is_OK_Static_Expression (Mod_Expr) then
18982 Flag_Non_Static_Expr
18983 ("non-static expression used for modular type bound!", Mod_Expr);
18984 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18986 M_Val := Expr_Value (Mod_Expr);
18990 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18991 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18994 if M_Val > 2 ** Standard_Long_Integer_Size then
18995 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18998 Set_Modulus (T, M_Val);
19000 -- Create bounds for the modular type based on the modulus given in
19001 -- the type declaration and then analyze and resolve those bounds.
19003 Set_Scalar_Range (T,
19004 Make_Range (Sloc (Mod_Expr),
19005 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
19006 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
19008 -- Properly analyze the literals for the range. We do this manually
19009 -- because we can't go calling Resolve, since we are resolving these
19010 -- bounds with the type, and this type is certainly not complete yet.
19012 Set_Etype (Low_Bound (Scalar_Range (T)), T);
19013 Set_Etype (High_Bound (Scalar_Range (T)), T);
19014 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
19015 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
19017 -- Loop through powers of two to find number of bits required
19019 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
19023 if M_Val = 2 ** Bits then
19024 Set_Modular_Size (Bits);
19029 elsif M_Val < 2 ** Bits then
19030 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
19031 Set_Non_Binary_Modulus (T);
19033 if Bits > System_Max_Nonbinary_Modulus_Power then
19034 Error_Msg_Uint_1 :=
19035 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
19037 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
19038 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19042 -- In the nonbinary case, set size as per RM 13.3(55)
19044 Set_Modular_Size (Bits);
19051 -- If we fall through, then the size exceed System.Max_Binary_Modulus
19052 -- so we just signal an error and set the maximum size.
19054 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
19055 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
19057 Set_Modular_Size (System_Max_Binary_Modulus_Power);
19058 Init_Alignment (T);
19060 end Modular_Type_Declaration;
19062 --------------------------
19063 -- New_Concatenation_Op --
19064 --------------------------
19066 procedure New_Concatenation_Op (Typ : Entity_Id) is
19067 Loc : constant Source_Ptr := Sloc (Typ);
19070 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
19071 -- Create abbreviated declaration for the formal of a predefined
19072 -- Operator 'Op' of type 'Typ'
19074 --------------------
19075 -- Make_Op_Formal --
19076 --------------------
19078 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
19079 Formal : Entity_Id;
19081 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
19082 Set_Etype (Formal, Typ);
19083 Set_Mechanism (Formal, Default_Mechanism);
19085 end Make_Op_Formal;
19087 -- Start of processing for New_Concatenation_Op
19090 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
19092 Set_Ekind (Op, E_Operator);
19093 Set_Scope (Op, Current_Scope);
19094 Set_Etype (Op, Typ);
19095 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
19096 Set_Is_Immediately_Visible (Op);
19097 Set_Is_Intrinsic_Subprogram (Op);
19098 Set_Has_Completion (Op);
19099 Append_Entity (Op, Current_Scope);
19101 Set_Name_Entity_Id (Name_Op_Concat, Op);
19103 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19104 Append_Entity (Make_Op_Formal (Typ, Op), Op);
19105 end New_Concatenation_Op;
19107 -------------------------
19108 -- OK_For_Limited_Init --
19109 -------------------------
19111 -- ???Check all calls of this, and compare the conditions under which it's
19114 function OK_For_Limited_Init
19116 Exp : Node_Id) return Boolean
19119 return Is_CPP_Constructor_Call (Exp)
19120 or else (Ada_Version >= Ada_2005
19121 and then not Debug_Flag_Dot_L
19122 and then OK_For_Limited_Init_In_05 (Typ, Exp));
19123 end OK_For_Limited_Init;
19125 -------------------------------
19126 -- OK_For_Limited_Init_In_05 --
19127 -------------------------------
19129 function OK_For_Limited_Init_In_05
19131 Exp : Node_Id) return Boolean
19134 -- An object of a limited interface type can be initialized with any
19135 -- expression of a nonlimited descendant type. However this does not
19136 -- apply if this is a view conversion of some other expression. This
19137 -- is checked below.
19139 if Is_Class_Wide_Type (Typ)
19140 and then Is_Limited_Interface (Typ)
19141 and then not Is_Limited_Type (Etype (Exp))
19142 and then Nkind (Exp) /= N_Type_Conversion
19147 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
19148 -- case of limited aggregates (including extension aggregates), and
19149 -- function calls. The function call may have been given in prefixed
19150 -- notation, in which case the original node is an indexed component.
19151 -- If the function is parameterless, the original node was an explicit
19152 -- dereference. The function may also be parameterless, in which case
19153 -- the source node is just an identifier.
19155 -- A branch of a conditional expression may have been removed if the
19156 -- condition is statically known. This happens during expansion, and
19157 -- thus will not happen if previous errors were encountered. The check
19158 -- will have been performed on the chosen branch, which replaces the
19159 -- original conditional expression.
19165 case Nkind (Original_Node (Exp)) is
19167 | N_Extension_Aggregate
19173 when N_Identifier =>
19174 return Present (Entity (Original_Node (Exp)))
19175 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
19177 when N_Qualified_Expression =>
19179 OK_For_Limited_Init_In_05
19180 (Typ, Expression (Original_Node (Exp)));
19182 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
19183 -- with a function call, the expander has rewritten the call into an
19184 -- N_Type_Conversion node to force displacement of the pointer to
19185 -- reference the component containing the secondary dispatch table.
19186 -- Otherwise a type conversion is not a legal context.
19187 -- A return statement for a build-in-place function returning a
19188 -- synchronized type also introduces an unchecked conversion.
19190 when N_Type_Conversion
19191 | N_Unchecked_Type_Conversion
19193 return not Comes_From_Source (Exp)
19195 OK_For_Limited_Init_In_05
19196 (Typ, Expression (Original_Node (Exp)));
19198 when N_Explicit_Dereference
19199 | N_Indexed_Component
19200 | N_Selected_Component
19202 return Nkind (Exp) = N_Function_Call;
19204 -- A use of 'Input is a function call, hence allowed. Normally the
19205 -- attribute will be changed to a call, but the attribute by itself
19206 -- can occur with -gnatc.
19208 when N_Attribute_Reference =>
19209 return Attribute_Name (Original_Node (Exp)) = Name_Input;
19211 -- For a case expression, all dependent expressions must be legal
19213 when N_Case_Expression =>
19218 Alt := First (Alternatives (Original_Node (Exp)));
19219 while Present (Alt) loop
19220 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
19230 -- For an if expression, all dependent expressions must be legal
19232 when N_If_Expression =>
19234 Then_Expr : constant Node_Id :=
19235 Next (First (Expressions (Original_Node (Exp))));
19236 Else_Expr : constant Node_Id := Next (Then_Expr);
19238 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
19240 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
19246 end OK_For_Limited_Init_In_05;
19248 -------------------------------------------
19249 -- Ordinary_Fixed_Point_Type_Declaration --
19250 -------------------------------------------
19252 procedure Ordinary_Fixed_Point_Type_Declaration
19256 Loc : constant Source_Ptr := Sloc (Def);
19257 Delta_Expr : constant Node_Id := Delta_Expression (Def);
19258 RRS : constant Node_Id := Real_Range_Specification (Def);
19259 Implicit_Base : Entity_Id;
19266 Check_Restriction (No_Fixed_Point, Def);
19268 -- Create implicit base type
19271 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
19272 Set_Etype (Implicit_Base, Implicit_Base);
19274 -- Analyze and process delta expression
19276 Analyze_And_Resolve (Delta_Expr, Any_Real);
19278 Check_Delta_Expression (Delta_Expr);
19279 Delta_Val := Expr_Value_R (Delta_Expr);
19281 Set_Delta_Value (Implicit_Base, Delta_Val);
19283 -- Compute default small from given delta, which is the largest power
19284 -- of two that does not exceed the given delta value.
19294 if Delta_Val < Ureal_1 then
19295 while Delta_Val < Tmp loop
19296 Tmp := Tmp / Ureal_2;
19297 Scale := Scale + 1;
19302 Tmp := Tmp * Ureal_2;
19303 exit when Tmp > Delta_Val;
19304 Scale := Scale - 1;
19308 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
19311 Set_Small_Value (Implicit_Base, Small_Val);
19313 -- If no range was given, set a dummy range
19315 if RRS <= Empty_Or_Error then
19316 Low_Val := -Small_Val;
19317 High_Val := Small_Val;
19319 -- Otherwise analyze and process given range
19323 Low : constant Node_Id := Low_Bound (RRS);
19324 High : constant Node_Id := High_Bound (RRS);
19327 Analyze_And_Resolve (Low, Any_Real);
19328 Analyze_And_Resolve (High, Any_Real);
19329 Check_Real_Bound (Low);
19330 Check_Real_Bound (High);
19332 -- Obtain and set the range
19334 Low_Val := Expr_Value_R (Low);
19335 High_Val := Expr_Value_R (High);
19337 if Low_Val > High_Val then
19338 Error_Msg_NE ("??fixed point type& has null range", Def, T);
19343 -- The range for both the implicit base and the declared first subtype
19344 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
19345 -- set a temporary range in place. Note that the bounds of the base
19346 -- type will be widened to be symmetrical and to fill the available
19347 -- bits when the type is frozen.
19349 -- We could do this with all discrete types, and probably should, but
19350 -- we absolutely have to do it for fixed-point, since the end-points
19351 -- of the range and the size are determined by the small value, which
19352 -- could be reset before the freeze point.
19354 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
19355 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
19357 -- Complete definition of first subtype. The inheritance of the rep item
19358 -- chain ensures that SPARK-related pragmas are not clobbered when the
19359 -- ordinary fixed point type acts as a full view of a private type.
19361 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
19362 Set_Etype (T, Implicit_Base);
19363 Init_Size_Align (T);
19364 Inherit_Rep_Item_Chain (T, Implicit_Base);
19365 Set_Small_Value (T, Small_Val);
19366 Set_Delta_Value (T, Delta_Val);
19367 Set_Is_Constrained (T);
19368 end Ordinary_Fixed_Point_Type_Declaration;
19370 ----------------------------------
19371 -- Preanalyze_Assert_Expression --
19372 ----------------------------------
19374 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19376 In_Assertion_Expr := In_Assertion_Expr + 1;
19377 Preanalyze_Spec_Expression (N, T);
19378 In_Assertion_Expr := In_Assertion_Expr - 1;
19379 end Preanalyze_Assert_Expression;
19381 -----------------------------------
19382 -- Preanalyze_Default_Expression --
19383 -----------------------------------
19385 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19386 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19388 In_Default_Expr := True;
19389 Preanalyze_Spec_Expression (N, T);
19390 In_Default_Expr := Save_In_Default_Expr;
19391 end Preanalyze_Default_Expression;
19393 --------------------------------
19394 -- Preanalyze_Spec_Expression --
19395 --------------------------------
19397 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19398 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19400 In_Spec_Expression := True;
19401 Preanalyze_And_Resolve (N, T);
19402 In_Spec_Expression := Save_In_Spec_Expression;
19403 end Preanalyze_Spec_Expression;
19405 ----------------------------------------
19406 -- Prepare_Private_Subtype_Completion --
19407 ----------------------------------------
19409 procedure Prepare_Private_Subtype_Completion
19411 Related_Nod : Node_Id)
19413 Id_B : constant Entity_Id := Base_Type (Id);
19414 Full_B : Entity_Id := Full_View (Id_B);
19418 if Present (Full_B) then
19420 -- Get to the underlying full view if necessary
19422 if Is_Private_Type (Full_B)
19423 and then Present (Underlying_Full_View (Full_B))
19425 Full_B := Underlying_Full_View (Full_B);
19428 -- The Base_Type is already completed, we can complete the subtype
19429 -- now. We have to create a new entity with the same name, Thus we
19430 -- can't use Create_Itype.
19432 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19433 Set_Is_Itype (Full);
19434 Set_Associated_Node_For_Itype (Full, Related_Nod);
19435 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19438 -- The parent subtype may be private, but the base might not, in some
19439 -- nested instances. In that case, the subtype does not need to be
19440 -- exchanged. It would still be nice to make private subtypes and their
19441 -- bases consistent at all times ???
19443 if Is_Private_Type (Id_B) then
19444 Append_Elmt (Id, Private_Dependents (Id_B));
19446 end Prepare_Private_Subtype_Completion;
19448 ---------------------------
19449 -- Process_Discriminants --
19450 ---------------------------
19452 procedure Process_Discriminants
19454 Prev : Entity_Id := Empty)
19456 Elist : constant Elist_Id := New_Elmt_List;
19459 Discr_Number : Uint;
19460 Discr_Type : Entity_Id;
19461 Default_Present : Boolean := False;
19462 Default_Not_Present : Boolean := False;
19465 -- A composite type other than an array type can have discriminants.
19466 -- On entry, the current scope is the composite type.
19468 -- The discriminants are initially entered into the scope of the type
19469 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19470 -- use, as explained at the end of this procedure.
19472 Discr := First (Discriminant_Specifications (N));
19473 while Present (Discr) loop
19474 Enter_Name (Defining_Identifier (Discr));
19476 -- For navigation purposes we add a reference to the discriminant
19477 -- in the entity for the type. If the current declaration is a
19478 -- completion, place references on the partial view. Otherwise the
19479 -- type is the current scope.
19481 if Present (Prev) then
19483 -- The references go on the partial view, if present. If the
19484 -- partial view has discriminants, the references have been
19485 -- generated already.
19487 if not Has_Discriminants (Prev) then
19488 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19492 (Current_Scope, Defining_Identifier (Discr), 'd');
19495 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19496 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19498 -- Ada 2005 (AI-254)
19500 if Present (Access_To_Subprogram_Definition
19501 (Discriminant_Type (Discr)))
19502 and then Protected_Present (Access_To_Subprogram_Definition
19503 (Discriminant_Type (Discr)))
19506 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19510 Find_Type (Discriminant_Type (Discr));
19511 Discr_Type := Etype (Discriminant_Type (Discr));
19513 if Error_Posted (Discriminant_Type (Discr)) then
19514 Discr_Type := Any_Type;
19518 -- Handling of discriminants that are access types
19520 if Is_Access_Type (Discr_Type) then
19522 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19523 -- limited record types
19525 if Ada_Version < Ada_2005 then
19526 Check_Access_Discriminant_Requires_Limited
19527 (Discr, Discriminant_Type (Discr));
19530 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19532 ("(Ada 83) access discriminant not allowed", Discr);
19535 -- If not access type, must be a discrete type
19537 elsif not Is_Discrete_Type (Discr_Type) then
19539 ("discriminants must have a discrete or access type",
19540 Discriminant_Type (Discr));
19543 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19545 -- If a discriminant specification includes the assignment compound
19546 -- delimiter followed by an expression, the expression is the default
19547 -- expression of the discriminant; the default expression must be of
19548 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19549 -- a default expression, we do the special preanalysis, since this
19550 -- expression does not freeze (see section "Handling of Default and
19551 -- Per-Object Expressions" in spec of package Sem).
19553 if Present (Expression (Discr)) then
19554 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19558 if Nkind (N) = N_Formal_Type_Declaration then
19560 ("discriminant defaults not allowed for formal type",
19561 Expression (Discr));
19563 -- Flag an error for a tagged type with defaulted discriminants,
19564 -- excluding limited tagged types when compiling for Ada 2012
19565 -- (see AI05-0214).
19567 elsif Is_Tagged_Type (Current_Scope)
19568 and then (not Is_Limited_Type (Current_Scope)
19569 or else Ada_Version < Ada_2012)
19570 and then Comes_From_Source (N)
19572 -- Note: see similar test in Check_Or_Process_Discriminants, to
19573 -- handle the (illegal) case of the completion of an untagged
19574 -- view with discriminants with defaults by a tagged full view.
19575 -- We skip the check if Discr does not come from source, to
19576 -- account for the case of an untagged derived type providing
19577 -- defaults for a renamed discriminant from a private untagged
19578 -- ancestor with a tagged full view (ACATS B460006).
19580 if Ada_Version >= Ada_2012 then
19582 ("discriminants of nonlimited tagged type cannot have"
19584 Expression (Discr));
19587 ("discriminants of tagged type cannot have defaults",
19588 Expression (Discr));
19592 Default_Present := True;
19593 Append_Elmt (Expression (Discr), Elist);
19595 -- Tag the defining identifiers for the discriminants with
19596 -- their corresponding default expressions from the tree.
19598 Set_Discriminant_Default_Value
19599 (Defining_Identifier (Discr), Expression (Discr));
19602 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19603 -- gets set unless we can be sure that no range check is required.
19605 if (GNATprove_Mode or not Expander_Active)
19608 (Expression (Discr), Discr_Type, Assume_Valid => True)
19610 Set_Do_Range_Check (Expression (Discr));
19613 -- No default discriminant value given
19616 Default_Not_Present := True;
19619 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19620 -- Discr_Type but with the null-exclusion attribute
19622 if Ada_Version >= Ada_2005 then
19624 -- Ada 2005 (AI-231): Static checks
19626 if Can_Never_Be_Null (Discr_Type) then
19627 Null_Exclusion_Static_Checks (Discr);
19629 elsif Is_Access_Type (Discr_Type)
19630 and then Null_Exclusion_Present (Discr)
19632 -- No need to check itypes because in their case this check
19633 -- was done at their point of creation
19635 and then not Is_Itype (Discr_Type)
19637 if Can_Never_Be_Null (Discr_Type) then
19639 ("`NOT NULL` not allowed (& already excludes null)",
19644 Set_Etype (Defining_Identifier (Discr),
19645 Create_Null_Excluding_Itype
19647 Related_Nod => Discr));
19649 -- Check for improper null exclusion if the type is otherwise
19650 -- legal for a discriminant.
19652 elsif Null_Exclusion_Present (Discr)
19653 and then Is_Discrete_Type (Discr_Type)
19656 ("null exclusion can only apply to an access type", Discr);
19659 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19660 -- can't have defaults. Synchronized types, or types that are
19661 -- explicitly limited are fine, but special tests apply to derived
19662 -- types in generics: in a generic body we have to assume the
19663 -- worst, and therefore defaults are not allowed if the parent is
19664 -- a generic formal private type (see ACATS B370001).
19666 if Is_Access_Type (Discr_Type) and then Default_Present then
19667 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19668 or else Is_Limited_Record (Current_Scope)
19669 or else Is_Concurrent_Type (Current_Scope)
19670 or else Is_Concurrent_Record_Type (Current_Scope)
19671 or else Ekind (Current_Scope) = E_Limited_Private_Type
19673 if not Is_Derived_Type (Current_Scope)
19674 or else not Is_Generic_Type (Etype (Current_Scope))
19675 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19676 or else Limited_Present
19677 (Type_Definition (Parent (Current_Scope)))
19683 ("access discriminants of nonlimited types cannot "
19684 & "have defaults", Expression (Discr));
19687 elsif Present (Expression (Discr)) then
19689 ("(Ada 2005) access discriminants of nonlimited types "
19690 & "cannot have defaults", Expression (Discr));
19695 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19696 -- This check is relevant only when SPARK_Mode is on as it is not a
19697 -- standard Ada legality rule.
19700 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19702 Error_Msg_N ("discriminant cannot be volatile", Discr);
19708 -- An element list consisting of the default expressions of the
19709 -- discriminants is constructed in the above loop and used to set
19710 -- the Discriminant_Constraint attribute for the type. If an object
19711 -- is declared of this (record or task) type without any explicit
19712 -- discriminant constraint given, this element list will form the
19713 -- actual parameters for the corresponding initialization procedure
19716 Set_Discriminant_Constraint (Current_Scope, Elist);
19717 Set_Stored_Constraint (Current_Scope, No_Elist);
19719 -- Default expressions must be provided either for all or for none
19720 -- of the discriminants of a discriminant part. (RM 3.7.1)
19722 if Default_Present and then Default_Not_Present then
19724 ("incomplete specification of defaults for discriminants", N);
19727 -- The use of the name of a discriminant is not allowed in default
19728 -- expressions of a discriminant part if the specification of the
19729 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19731 -- To detect this, the discriminant names are entered initially with an
19732 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19733 -- attempt to use a void entity (for example in an expression that is
19734 -- type-checked) produces the error message: premature usage. Now after
19735 -- completing the semantic analysis of the discriminant part, we can set
19736 -- the Ekind of all the discriminants appropriately.
19738 Discr := First (Discriminant_Specifications (N));
19739 Discr_Number := Uint_1;
19740 while Present (Discr) loop
19741 Id := Defining_Identifier (Discr);
19742 Set_Ekind (Id, E_Discriminant);
19743 Init_Component_Location (Id);
19745 Set_Discriminant_Number (Id, Discr_Number);
19747 -- Make sure this is always set, even in illegal programs
19749 Set_Corresponding_Discriminant (Id, Empty);
19751 -- Initialize the Original_Record_Component to the entity itself.
19752 -- Inherit_Components will propagate the right value to
19753 -- discriminants in derived record types.
19755 Set_Original_Record_Component (Id, Id);
19757 -- Create the discriminal for the discriminant
19759 Build_Discriminal (Id);
19762 Discr_Number := Discr_Number + 1;
19765 Set_Has_Discriminants (Current_Scope);
19766 end Process_Discriminants;
19768 -----------------------
19769 -- Process_Full_View --
19770 -----------------------
19772 -- WARNING: This routine manages Ghost regions. Return statements must be
19773 -- replaced by gotos which jump to the end of the routine and restore the
19776 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19777 procedure Collect_Implemented_Interfaces
19779 Ifaces : Elist_Id);
19780 -- Ada 2005: Gather all the interfaces that Typ directly or
19781 -- inherently implements. Duplicate entries are not added to
19782 -- the list Ifaces.
19784 ------------------------------------
19785 -- Collect_Implemented_Interfaces --
19786 ------------------------------------
19788 procedure Collect_Implemented_Interfaces
19793 Iface_Elmt : Elmt_Id;
19796 -- Abstract interfaces are only associated with tagged record types
19798 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19802 -- Recursively climb to the ancestors
19804 if Etype (Typ) /= Typ
19806 -- Protect the frontend against wrong cyclic declarations like:
19808 -- type B is new A with private;
19809 -- type C is new A with private;
19811 -- type B is new C with null record;
19812 -- type C is new B with null record;
19814 and then Etype (Typ) /= Priv_T
19815 and then Etype (Typ) /= Full_T
19817 -- Keep separate the management of private type declarations
19819 if Ekind (Typ) = E_Record_Type_With_Private then
19821 -- Handle the following illegal usage:
19822 -- type Private_Type is tagged private;
19824 -- type Private_Type is new Type_Implementing_Iface;
19826 if Present (Full_View (Typ))
19827 and then Etype (Typ) /= Full_View (Typ)
19829 if Is_Interface (Etype (Typ)) then
19830 Append_Unique_Elmt (Etype (Typ), Ifaces);
19833 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19836 -- Non-private types
19839 if Is_Interface (Etype (Typ)) then
19840 Append_Unique_Elmt (Etype (Typ), Ifaces);
19843 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19847 -- Handle entities in the list of abstract interfaces
19849 if Present (Interfaces (Typ)) then
19850 Iface_Elmt := First_Elmt (Interfaces (Typ));
19851 while Present (Iface_Elmt) loop
19852 Iface := Node (Iface_Elmt);
19854 pragma Assert (Is_Interface (Iface));
19856 if not Contain_Interface (Iface, Ifaces) then
19857 Append_Elmt (Iface, Ifaces);
19858 Collect_Implemented_Interfaces (Iface, Ifaces);
19861 Next_Elmt (Iface_Elmt);
19864 end Collect_Implemented_Interfaces;
19868 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
19870 Full_Indic : Node_Id;
19871 Full_Parent : Entity_Id;
19872 Priv_Parent : Entity_Id;
19874 -- Start of processing for Process_Full_View
19877 Mark_And_Set_Ghost_Completion (N, Priv_T);
19879 -- First some sanity checks that must be done after semantic
19880 -- decoration of the full view and thus cannot be placed with other
19881 -- similar checks in Find_Type_Name
19883 if not Is_Limited_Type (Priv_T)
19884 and then (Is_Limited_Type (Full_T)
19885 or else Is_Limited_Composite (Full_T))
19887 if In_Instance then
19891 ("completion of nonlimited type cannot be limited", Full_T);
19892 Explain_Limited_Type (Full_T, Full_T);
19895 elsif Is_Abstract_Type (Full_T)
19896 and then not Is_Abstract_Type (Priv_T)
19899 ("completion of nonabstract type cannot be abstract", Full_T);
19901 elsif Is_Tagged_Type (Priv_T)
19902 and then Is_Limited_Type (Priv_T)
19903 and then not Is_Limited_Type (Full_T)
19905 -- If pragma CPP_Class was applied to the private declaration
19906 -- propagate the limitedness to the full-view
19908 if Is_CPP_Class (Priv_T) then
19909 Set_Is_Limited_Record (Full_T);
19911 -- GNAT allow its own definition of Limited_Controlled to disobey
19912 -- this rule in order in ease the implementation. This test is safe
19913 -- because Root_Controlled is defined in a child of System that
19914 -- normal programs are not supposed to use.
19916 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19917 Set_Is_Limited_Composite (Full_T);
19920 ("completion of limited tagged type must be limited", Full_T);
19923 elsif Is_Generic_Type (Priv_T) then
19924 Error_Msg_N ("generic type cannot have a completion", Full_T);
19927 -- Check that ancestor interfaces of private and full views are
19928 -- consistent. We omit this check for synchronized types because
19929 -- they are performed on the corresponding record type when frozen.
19931 if Ada_Version >= Ada_2005
19932 and then Is_Tagged_Type (Priv_T)
19933 and then Is_Tagged_Type (Full_T)
19934 and then not Is_Concurrent_Type (Full_T)
19938 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19939 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19942 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19943 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19945 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19946 -- an interface type if and only if the full type is descendant
19947 -- of the interface type (AARM 7.3 (7.3/2)).
19949 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19951 if Present (Iface) then
19953 ("interface in partial view& not implemented by full type "
19954 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19957 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19959 if Present (Iface) then
19961 ("interface & not implemented by partial view "
19962 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19967 if Is_Tagged_Type (Priv_T)
19968 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19969 and then Is_Derived_Type (Full_T)
19971 Priv_Parent := Etype (Priv_T);
19973 -- The full view of a private extension may have been transformed
19974 -- into an unconstrained derived type declaration and a subtype
19975 -- declaration (see build_derived_record_type for details).
19977 if Nkind (N) = N_Subtype_Declaration then
19978 Full_Indic := Subtype_Indication (N);
19979 Full_Parent := Etype (Base_Type (Full_T));
19981 Full_Indic := Subtype_Indication (Type_Definition (N));
19982 Full_Parent := Etype (Full_T);
19985 -- Check that the parent type of the full type is a descendant of
19986 -- the ancestor subtype given in the private extension. If either
19987 -- entity has an Etype equal to Any_Type then we had some previous
19988 -- error situation [7.3(8)].
19990 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19993 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19994 -- any order. Therefore we don't have to check that its parent must
19995 -- be a descendant of the parent of the private type declaration.
19997 elsif Is_Interface (Priv_Parent)
19998 and then Is_Interface (Full_Parent)
20002 -- Ada 2005 (AI-251): If the parent of the private type declaration
20003 -- is an interface there is no need to check that it is an ancestor
20004 -- of the associated full type declaration. The required tests for
20005 -- this case are performed by Build_Derived_Record_Type.
20007 elsif not Is_Interface (Base_Type (Priv_Parent))
20008 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
20011 ("parent of full type must descend from parent of private "
20012 & "extension", Full_Indic);
20014 -- First check a formal restriction, and then proceed with checking
20015 -- Ada rules. Since the formal restriction is not a serious error, we
20016 -- don't prevent further error detection for this check, hence the
20020 -- In formal mode, when completing a private extension the type
20021 -- named in the private part must be exactly the same as that
20022 -- named in the visible part.
20024 if Priv_Parent /= Full_Parent then
20025 Error_Msg_Name_1 := Chars (Priv_Parent);
20026 Check_SPARK_05_Restriction ("% expected", Full_Indic);
20029 -- Check the rules of 7.3(10): if the private extension inherits
20030 -- known discriminants, then the full type must also inherit those
20031 -- discriminants from the same (ancestor) type, and the parent
20032 -- subtype of the full type must be constrained if and only if
20033 -- the ancestor subtype of the private extension is constrained.
20035 if No (Discriminant_Specifications (Parent (Priv_T)))
20036 and then not Has_Unknown_Discriminants (Priv_T)
20037 and then Has_Discriminants (Base_Type (Priv_Parent))
20040 Priv_Indic : constant Node_Id :=
20041 Subtype_Indication (Parent (Priv_T));
20043 Priv_Constr : constant Boolean :=
20044 Is_Constrained (Priv_Parent)
20046 Nkind (Priv_Indic) = N_Subtype_Indication
20048 Is_Constrained (Entity (Priv_Indic));
20050 Full_Constr : constant Boolean :=
20051 Is_Constrained (Full_Parent)
20053 Nkind (Full_Indic) = N_Subtype_Indication
20055 Is_Constrained (Entity (Full_Indic));
20057 Priv_Discr : Entity_Id;
20058 Full_Discr : Entity_Id;
20061 Priv_Discr := First_Discriminant (Priv_Parent);
20062 Full_Discr := First_Discriminant (Full_Parent);
20063 while Present (Priv_Discr) and then Present (Full_Discr) loop
20064 if Original_Record_Component (Priv_Discr) =
20065 Original_Record_Component (Full_Discr)
20067 Corresponding_Discriminant (Priv_Discr) =
20068 Corresponding_Discriminant (Full_Discr)
20075 Next_Discriminant (Priv_Discr);
20076 Next_Discriminant (Full_Discr);
20079 if Present (Priv_Discr) or else Present (Full_Discr) then
20081 ("full view must inherit discriminants of the parent "
20082 & "type used in the private extension", Full_Indic);
20084 elsif Priv_Constr and then not Full_Constr then
20086 ("parent subtype of full type must be constrained",
20089 elsif Full_Constr and then not Priv_Constr then
20091 ("parent subtype of full type must be unconstrained",
20096 -- Check the rules of 7.3(12): if a partial view has neither
20097 -- known or unknown discriminants, then the full type
20098 -- declaration shall define a definite subtype.
20100 elsif not Has_Unknown_Discriminants (Priv_T)
20101 and then not Has_Discriminants (Priv_T)
20102 and then not Is_Constrained (Full_T)
20105 ("full view must define a constrained type if partial view "
20106 & "has no discriminants", Full_T);
20109 -- ??????? Do we implement the following properly ?????
20110 -- If the ancestor subtype of a private extension has constrained
20111 -- discriminants, then the parent subtype of the full view shall
20112 -- impose a statically matching constraint on those discriminants
20117 -- For untagged types, verify that a type without discriminants is
20118 -- not completed with an unconstrained type. A separate error message
20119 -- is produced if the full type has defaulted discriminants.
20121 if Is_Definite_Subtype (Priv_T)
20122 and then not Is_Definite_Subtype (Full_T)
20124 Error_Msg_Sloc := Sloc (Parent (Priv_T));
20126 ("full view of& not compatible with declaration#",
20129 if not Is_Tagged_Type (Full_T) then
20131 ("\one is constrained, the other unconstrained", Full_T);
20136 -- AI-419: verify that the use of "limited" is consistent
20139 Orig_Decl : constant Node_Id := Original_Node (N);
20142 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20143 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
20145 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
20147 if not Limited_Present (Parent (Priv_T))
20148 and then not Synchronized_Present (Parent (Priv_T))
20149 and then Limited_Present (Type_Definition (Orig_Decl))
20152 ("full view of non-limited extension cannot be limited", N);
20154 -- Conversely, if the partial view carries the limited keyword,
20155 -- the full view must as well, even if it may be redundant.
20157 elsif Limited_Present (Parent (Priv_T))
20158 and then not Limited_Present (Type_Definition (Orig_Decl))
20161 ("full view of limited extension must be explicitly limited",
20167 -- Ada 2005 (AI-443): A synchronized private extension must be
20168 -- completed by a task or protected type.
20170 if Ada_Version >= Ada_2005
20171 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
20172 and then Synchronized_Present (Parent (Priv_T))
20173 and then not Is_Concurrent_Type (Full_T)
20175 Error_Msg_N ("full view of synchronized extension must " &
20176 "be synchronized type", N);
20179 -- Ada 2005 AI-363: if the full view has discriminants with
20180 -- defaults, it is illegal to declare constrained access subtypes
20181 -- whose designated type is the current type. This allows objects
20182 -- of the type that are declared in the heap to be unconstrained.
20184 if not Has_Unknown_Discriminants (Priv_T)
20185 and then not Has_Discriminants (Priv_T)
20186 and then Has_Discriminants (Full_T)
20188 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
20190 Set_Has_Constrained_Partial_View (Full_T);
20191 Set_Has_Constrained_Partial_View (Priv_T);
20194 -- Create a full declaration for all its subtypes recorded in
20195 -- Private_Dependents and swap them similarly to the base type. These
20196 -- are subtypes that have been define before the full declaration of
20197 -- the private type. We also swap the entry in Private_Dependents list
20198 -- so we can properly restore the private view on exit from the scope.
20201 Priv_Elmt : Elmt_Id;
20202 Priv_Scop : Entity_Id;
20207 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
20208 while Present (Priv_Elmt) loop
20209 Priv := Node (Priv_Elmt);
20210 Priv_Scop := Scope (Priv);
20212 if Ekind_In (Priv, E_Private_Subtype,
20213 E_Limited_Private_Subtype,
20214 E_Record_Subtype_With_Private)
20216 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
20217 Set_Is_Itype (Full);
20218 Set_Parent (Full, Parent (Priv));
20219 Set_Associated_Node_For_Itype (Full, N);
20221 -- Now we need to complete the private subtype, but since the
20222 -- base type has already been swapped, we must also swap the
20223 -- subtypes (and thus, reverse the arguments in the call to
20224 -- Complete_Private_Subtype). Also note that we may need to
20225 -- re-establish the scope of the private subtype.
20227 Copy_And_Swap (Priv, Full);
20229 if not In_Open_Scopes (Priv_Scop) then
20230 Push_Scope (Priv_Scop);
20233 -- Reset Priv_Scop to Empty to indicate no scope was pushed
20235 Priv_Scop := Empty;
20238 Complete_Private_Subtype (Full, Priv, Full_T, N);
20240 if Present (Priv_Scop) then
20244 Replace_Elmt (Priv_Elmt, Full);
20247 Next_Elmt (Priv_Elmt);
20251 -- If the private view was tagged, copy the new primitive operations
20252 -- from the private view to the full view.
20254 if Is_Tagged_Type (Full_T) then
20256 Disp_Typ : Entity_Id;
20257 Full_List : Elist_Id;
20259 Prim_Elmt : Elmt_Id;
20260 Priv_List : Elist_Id;
20264 L : Elist_Id) return Boolean;
20265 -- Determine whether list L contains element E
20273 L : Elist_Id) return Boolean
20275 List_Elmt : Elmt_Id;
20278 List_Elmt := First_Elmt (L);
20279 while Present (List_Elmt) loop
20280 if Node (List_Elmt) = E then
20284 Next_Elmt (List_Elmt);
20290 -- Start of processing
20293 if Is_Tagged_Type (Priv_T) then
20294 Priv_List := Primitive_Operations (Priv_T);
20295 Prim_Elmt := First_Elmt (Priv_List);
20297 -- In the case of a concurrent type completing a private tagged
20298 -- type, primitives may have been declared in between the two
20299 -- views. These subprograms need to be wrapped the same way
20300 -- entries and protected procedures are handled because they
20301 -- cannot be directly shared by the two views.
20303 if Is_Concurrent_Type (Full_T) then
20305 Conc_Typ : constant Entity_Id :=
20306 Corresponding_Record_Type (Full_T);
20307 Curr_Nod : Node_Id := Parent (Conc_Typ);
20308 Wrap_Spec : Node_Id;
20311 while Present (Prim_Elmt) loop
20312 Prim := Node (Prim_Elmt);
20314 if Comes_From_Source (Prim)
20315 and then not Is_Abstract_Subprogram (Prim)
20318 Make_Subprogram_Declaration (Sloc (Prim),
20322 Obj_Typ => Conc_Typ,
20324 Parameter_Specifications
20327 Insert_After (Curr_Nod, Wrap_Spec);
20328 Curr_Nod := Wrap_Spec;
20330 Analyze (Wrap_Spec);
20332 -- Remove the wrapper from visibility to avoid
20333 -- spurious conflict with the wrapped entity.
20335 Set_Is_Immediately_Visible
20336 (Defining_Entity (Specification (Wrap_Spec)),
20340 Next_Elmt (Prim_Elmt);
20346 -- For non-concurrent types, transfer explicit primitives, but
20347 -- omit those inherited from the parent of the private view
20348 -- since they will be re-inherited later on.
20351 Full_List := Primitive_Operations (Full_T);
20353 while Present (Prim_Elmt) loop
20354 Prim := Node (Prim_Elmt);
20356 if Comes_From_Source (Prim)
20357 and then not Contains (Prim, Full_List)
20359 Append_Elmt (Prim, Full_List);
20362 Next_Elmt (Prim_Elmt);
20366 -- Untagged private view
20369 Full_List := Primitive_Operations (Full_T);
20371 -- In this case the partial view is untagged, so here we locate
20372 -- all of the earlier primitives that need to be treated as
20373 -- dispatching (those that appear between the two views). Note
20374 -- that these additional operations must all be new operations
20375 -- (any earlier operations that override inherited operations
20376 -- of the full view will already have been inserted in the
20377 -- primitives list, marked by Check_Operation_From_Private_View
20378 -- as dispatching. Note that implicit "/=" operators are
20379 -- excluded from being added to the primitives list since they
20380 -- shouldn't be treated as dispatching (tagged "/=" is handled
20383 Prim := Next_Entity (Full_T);
20384 while Present (Prim) and then Prim /= Priv_T loop
20385 if Ekind_In (Prim, E_Procedure, E_Function) then
20386 Disp_Typ := Find_Dispatching_Type (Prim);
20388 if Disp_Typ = Full_T
20389 and then (Chars (Prim) /= Name_Op_Ne
20390 or else Comes_From_Source (Prim))
20392 Check_Controlling_Formals (Full_T, Prim);
20394 if not Is_Dispatching_Operation (Prim) then
20395 Append_Elmt (Prim, Full_List);
20396 Set_Is_Dispatching_Operation (Prim, True);
20397 Set_DT_Position_Value (Prim, No_Uint);
20400 elsif Is_Dispatching_Operation (Prim)
20401 and then Disp_Typ /= Full_T
20404 -- Verify that it is not otherwise controlled by a
20405 -- formal or a return value of type T.
20407 Check_Controlling_Formals (Disp_Typ, Prim);
20411 Next_Entity (Prim);
20415 -- For the tagged case, the two views can share the same primitive
20416 -- operations list and the same class-wide type. Update attributes
20417 -- of the class-wide type which depend on the full declaration.
20419 if Is_Tagged_Type (Priv_T) then
20420 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20421 Set_Class_Wide_Type
20422 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20424 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20429 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20431 if Known_To_Have_Preelab_Init (Priv_T) then
20433 -- Case where there is a pragma Preelaborable_Initialization. We
20434 -- always allow this in predefined units, which is cheating a bit,
20435 -- but it means we don't have to struggle to meet the requirements in
20436 -- the RM for having Preelaborable Initialization. Otherwise we
20437 -- require that the type meets the RM rules. But we can't check that
20438 -- yet, because of the rule about overriding Initialize, so we simply
20439 -- set a flag that will be checked at freeze time.
20441 if not In_Predefined_Unit (Full_T) then
20442 Set_Must_Have_Preelab_Init (Full_T);
20446 -- If pragma CPP_Class was applied to the private type declaration,
20447 -- propagate it now to the full type declaration.
20449 if Is_CPP_Class (Priv_T) then
20450 Set_Is_CPP_Class (Full_T);
20451 Set_Convention (Full_T, Convention_CPP);
20453 -- Check that components of imported CPP types do not have default
20456 Check_CPP_Type_Has_No_Defaults (Full_T);
20459 -- If the private view has user specified stream attributes, then so has
20462 -- Why the test, how could these flags be already set in Full_T ???
20464 if Has_Specified_Stream_Read (Priv_T) then
20465 Set_Has_Specified_Stream_Read (Full_T);
20468 if Has_Specified_Stream_Write (Priv_T) then
20469 Set_Has_Specified_Stream_Write (Full_T);
20472 if Has_Specified_Stream_Input (Priv_T) then
20473 Set_Has_Specified_Stream_Input (Full_T);
20476 if Has_Specified_Stream_Output (Priv_T) then
20477 Set_Has_Specified_Stream_Output (Full_T);
20480 -- Propagate Default_Initial_Condition-related attributes from the
20481 -- partial view to the full view and its base type.
20483 Propagate_DIC_Attributes (Full_T, From_Typ => Priv_T);
20484 Propagate_DIC_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20486 -- Propagate invariant-related attributes from the partial view to the
20487 -- full view and its base type.
20489 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20490 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20492 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20493 -- in the full view without advertising the inheritance in the partial
20494 -- view. This can only occur when the partial view has no parent type
20495 -- and the full view has an interface as a parent. Any other scenarios
20496 -- are illegal because implemented interfaces must match between the
20499 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20501 Full_Par : constant Entity_Id := Etype (Full_T);
20502 Priv_Par : constant Entity_Id := Etype (Priv_T);
20505 if not Is_Interface (Priv_Par)
20506 and then Is_Interface (Full_Par)
20507 and then Has_Inheritable_Invariants (Full_Par)
20510 ("hidden inheritance of class-wide type invariants not "
20516 -- Propagate predicates to full type, and predicate function if already
20517 -- defined. It is not clear that this can actually happen? the partial
20518 -- view cannot be frozen yet, and the predicate function has not been
20519 -- built. Still it is a cheap check and seems safer to make it.
20521 if Has_Predicates (Priv_T) then
20522 Set_Has_Predicates (Full_T);
20524 if Present (Predicate_Function (Priv_T)) then
20525 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20530 Restore_Ghost_Mode (Saved_GM);
20531 end Process_Full_View;
20533 -----------------------------------
20534 -- Process_Incomplete_Dependents --
20535 -----------------------------------
20537 procedure Process_Incomplete_Dependents
20539 Full_T : Entity_Id;
20542 Inc_Elmt : Elmt_Id;
20543 Priv_Dep : Entity_Id;
20544 New_Subt : Entity_Id;
20546 Disc_Constraint : Elist_Id;
20549 if No (Private_Dependents (Inc_T)) then
20553 -- Itypes that may be generated by the completion of an incomplete
20554 -- subtype are not used by the back-end and not attached to the tree.
20555 -- They are created only for constraint-checking purposes.
20557 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20558 while Present (Inc_Elmt) loop
20559 Priv_Dep := Node (Inc_Elmt);
20561 if Ekind (Priv_Dep) = E_Subprogram_Type then
20563 -- An Access_To_Subprogram type may have a return type or a
20564 -- parameter type that is incomplete. Replace with the full view.
20566 if Etype (Priv_Dep) = Inc_T then
20567 Set_Etype (Priv_Dep, Full_T);
20571 Formal : Entity_Id;
20574 Formal := First_Formal (Priv_Dep);
20575 while Present (Formal) loop
20576 if Etype (Formal) = Inc_T then
20577 Set_Etype (Formal, Full_T);
20580 Next_Formal (Formal);
20584 elsif Is_Overloadable (Priv_Dep) then
20586 -- If a subprogram in the incomplete dependents list is primitive
20587 -- for a tagged full type then mark it as a dispatching operation,
20588 -- check whether it overrides an inherited subprogram, and check
20589 -- restrictions on its controlling formals. Note that a protected
20590 -- operation is never dispatching: only its wrapper operation
20591 -- (which has convention Ada) is.
20593 if Is_Tagged_Type (Full_T)
20594 and then Is_Primitive (Priv_Dep)
20595 and then Convention (Priv_Dep) /= Convention_Protected
20597 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20598 Set_Is_Dispatching_Operation (Priv_Dep);
20599 Check_Controlling_Formals (Full_T, Priv_Dep);
20602 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20604 -- Can happen during processing of a body before the completion
20605 -- of a TA type. Ignore, because spec is also on dependent list.
20609 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20610 -- corresponding subtype of the full view.
20612 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20613 Set_Subtype_Indication
20614 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20615 Set_Etype (Priv_Dep, Full_T);
20616 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20617 Set_Analyzed (Parent (Priv_Dep), False);
20619 -- Reanalyze the declaration, suppressing the call to
20620 -- Enter_Name to avoid duplicate names.
20622 Analyze_Subtype_Declaration
20623 (N => Parent (Priv_Dep),
20626 -- Dependent is a subtype
20629 -- We build a new subtype indication using the full view of the
20630 -- incomplete parent. The discriminant constraints have been
20631 -- elaborated already at the point of the subtype declaration.
20633 New_Subt := Create_Itype (E_Void, N);
20635 if Has_Discriminants (Full_T) then
20636 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20638 Disc_Constraint := No_Elist;
20641 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20642 Set_Full_View (Priv_Dep, New_Subt);
20645 Next_Elmt (Inc_Elmt);
20647 end Process_Incomplete_Dependents;
20649 --------------------------------
20650 -- Process_Range_Expr_In_Decl --
20651 --------------------------------
20653 procedure Process_Range_Expr_In_Decl
20656 Subtyp : Entity_Id := Empty;
20657 Check_List : List_Id := Empty_List;
20658 R_Check_Off : Boolean := False;
20659 In_Iter_Schm : Boolean := False)
20662 R_Checks : Check_Result;
20663 Insert_Node : Node_Id;
20664 Def_Id : Entity_Id;
20667 Analyze_And_Resolve (R, Base_Type (T));
20669 if Nkind (R) = N_Range then
20671 -- In SPARK, all ranges should be static, with the exception of the
20672 -- discrete type definition of a loop parameter specification.
20674 if not In_Iter_Schm
20675 and then not Is_OK_Static_Range (R)
20677 Check_SPARK_05_Restriction ("range should be static", R);
20680 Lo := Low_Bound (R);
20681 Hi := High_Bound (R);
20683 -- Validity checks on the range of a quantified expression are
20684 -- delayed until the construct is transformed into a loop.
20686 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20687 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20691 -- We need to ensure validity of the bounds here, because if we
20692 -- go ahead and do the expansion, then the expanded code will get
20693 -- analyzed with range checks suppressed and we miss the check.
20695 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20696 -- the temporaries generated by routine Remove_Side_Effects by means
20697 -- of validity checks must use the same names. When a range appears
20698 -- in the parent of a generic, the range is processed with checks
20699 -- disabled as part of the generic context and with checks enabled
20700 -- for code generation purposes. This leads to link issues as the
20701 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20702 -- template sees the temporaries generated by Remove_Side_Effects.
20705 Validity_Check_Range (R, Subtyp);
20708 -- If there were errors in the declaration, try and patch up some
20709 -- common mistakes in the bounds. The cases handled are literals
20710 -- which are Integer where the expected type is Real and vice versa.
20711 -- These corrections allow the compilation process to proceed further
20712 -- along since some basic assumptions of the format of the bounds
20715 if Etype (R) = Any_Type then
20716 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20718 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20720 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20722 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20724 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20726 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20728 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20730 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20737 -- If the bounds of the range have been mistakenly given as string
20738 -- literals (perhaps in place of character literals), then an error
20739 -- has already been reported, but we rewrite the string literal as a
20740 -- bound of the range's type to avoid blowups in later processing
20741 -- that looks at static values.
20743 if Nkind (Lo) = N_String_Literal then
20745 Make_Attribute_Reference (Sloc (Lo),
20746 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20747 Attribute_Name => Name_First));
20748 Analyze_And_Resolve (Lo);
20751 if Nkind (Hi) = N_String_Literal then
20753 Make_Attribute_Reference (Sloc (Hi),
20754 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20755 Attribute_Name => Name_First));
20756 Analyze_And_Resolve (Hi);
20759 -- If bounds aren't scalar at this point then exit, avoiding
20760 -- problems with further processing of the range in this procedure.
20762 if not Is_Scalar_Type (Etype (Lo)) then
20766 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20767 -- then range of the base type. Here we check whether the bounds
20768 -- are in the range of the subtype itself. Note that if the bounds
20769 -- represent the null range the Constraint_Error exception should
20772 -- ??? The following code should be cleaned up as follows
20774 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20775 -- is done in the call to Range_Check (R, T); below
20777 -- 2. The use of R_Check_Off should be investigated and possibly
20778 -- removed, this would clean up things a bit.
20780 if Is_Null_Range (Lo, Hi) then
20784 -- Capture values of bounds and generate temporaries for them
20785 -- if needed, before applying checks, since checks may cause
20786 -- duplication of the expression without forcing evaluation.
20788 -- The forced evaluation removes side effects from expressions,
20789 -- which should occur also in GNATprove mode. Otherwise, we end up
20790 -- with unexpected insertions of actions at places where this is
20791 -- not supposed to occur, e.g. on default parameters of a call.
20793 if Expander_Active or GNATprove_Mode then
20795 -- Call Force_Evaluation to create declarations as needed to
20796 -- deal with side effects, and also create typ_FIRST/LAST
20797 -- entities for bounds if we have a subtype name.
20799 -- Note: we do this transformation even if expansion is not
20800 -- active if we are in GNATprove_Mode since the transformation
20801 -- is in general required to ensure that the resulting tree has
20802 -- proper Ada semantics.
20805 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20807 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20810 -- We use a flag here instead of suppressing checks on the type
20811 -- because the type we check against isn't necessarily the place
20812 -- where we put the check.
20814 if not R_Check_Off then
20815 R_Checks := Get_Range_Checks (R, T);
20817 -- Look up tree to find an appropriate insertion point. We
20818 -- can't just use insert_actions because later processing
20819 -- depends on the insertion node. Prior to Ada 2012 the
20820 -- insertion point could only be a declaration or a loop, but
20821 -- quantified expressions can appear within any context in an
20822 -- expression, and the insertion point can be any statement,
20823 -- pragma, or declaration.
20825 Insert_Node := Parent (R);
20826 while Present (Insert_Node) loop
20828 Nkind (Insert_Node) in N_Declaration
20831 (Insert_Node, N_Component_Declaration,
20832 N_Loop_Parameter_Specification,
20833 N_Function_Specification,
20834 N_Procedure_Specification);
20836 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20837 or else Nkind (Insert_Node) in
20838 N_Statement_Other_Than_Procedure_Call
20839 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20842 Insert_Node := Parent (Insert_Node);
20845 -- Why would Type_Decl not be present??? Without this test,
20846 -- short regression tests fail.
20848 if Present (Insert_Node) then
20850 -- Case of loop statement. Verify that the range is part
20851 -- of the subtype indication of the iteration scheme.
20853 if Nkind (Insert_Node) = N_Loop_Statement then
20858 Indic := Parent (R);
20859 while Present (Indic)
20860 and then Nkind (Indic) /= N_Subtype_Indication
20862 Indic := Parent (Indic);
20865 if Present (Indic) then
20866 Def_Id := Etype (Subtype_Mark (Indic));
20868 Insert_Range_Checks
20872 Sloc (Insert_Node),
20874 Do_Before => True);
20878 -- Insertion before a declaration. If the declaration
20879 -- includes discriminants, the list of applicable checks
20880 -- is given by the caller.
20882 elsif Nkind (Insert_Node) in N_Declaration then
20883 Def_Id := Defining_Identifier (Insert_Node);
20885 if (Ekind (Def_Id) = E_Record_Type
20886 and then Depends_On_Discriminant (R))
20888 (Ekind (Def_Id) = E_Protected_Type
20889 and then Has_Discriminants (Def_Id))
20891 Append_Range_Checks
20893 Check_List, Def_Id, Sloc (Insert_Node), R);
20896 Insert_Range_Checks
20898 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20902 -- Insertion before a statement. Range appears in the
20903 -- context of a quantified expression. Insertion will
20904 -- take place when expression is expanded.
20913 -- Case of other than an explicit N_Range node
20915 -- The forced evaluation removes side effects from expressions, which
20916 -- should occur also in GNATprove mode. Otherwise, we end up with
20917 -- unexpected insertions of actions at places where this is not
20918 -- supposed to occur, e.g. on default parameters of a call.
20920 elsif Expander_Active or GNATprove_Mode then
20921 Get_Index_Bounds (R, Lo, Hi);
20922 Force_Evaluation (Lo);
20923 Force_Evaluation (Hi);
20925 end Process_Range_Expr_In_Decl;
20927 --------------------------------------
20928 -- Process_Real_Range_Specification --
20929 --------------------------------------
20931 procedure Process_Real_Range_Specification (Def : Node_Id) is
20932 Spec : constant Node_Id := Real_Range_Specification (Def);
20935 Err : Boolean := False;
20937 procedure Analyze_Bound (N : Node_Id);
20938 -- Analyze and check one bound
20940 -------------------
20941 -- Analyze_Bound --
20942 -------------------
20944 procedure Analyze_Bound (N : Node_Id) is
20946 Analyze_And_Resolve (N, Any_Real);
20948 if not Is_OK_Static_Expression (N) then
20949 Flag_Non_Static_Expr
20950 ("bound in real type definition is not static!", N);
20955 -- Start of processing for Process_Real_Range_Specification
20958 if Present (Spec) then
20959 Lo := Low_Bound (Spec);
20960 Hi := High_Bound (Spec);
20961 Analyze_Bound (Lo);
20962 Analyze_Bound (Hi);
20964 -- If error, clear away junk range specification
20967 Set_Real_Range_Specification (Def, Empty);
20970 end Process_Real_Range_Specification;
20972 ---------------------
20973 -- Process_Subtype --
20974 ---------------------
20976 function Process_Subtype
20978 Related_Nod : Node_Id;
20979 Related_Id : Entity_Id := Empty;
20980 Suffix : Character := ' ') return Entity_Id
20983 Def_Id : Entity_Id;
20984 Error_Node : Node_Id;
20985 Full_View_Id : Entity_Id;
20986 Subtype_Mark_Id : Entity_Id;
20988 May_Have_Null_Exclusion : Boolean;
20990 procedure Check_Incomplete (T : Node_Id);
20991 -- Called to verify that an incomplete type is not used prematurely
20993 ----------------------
20994 -- Check_Incomplete --
20995 ----------------------
20997 procedure Check_Incomplete (T : Node_Id) is
20999 -- Ada 2005 (AI-412): Incomplete subtypes are legal
21001 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
21003 not (Ada_Version >= Ada_2005
21005 (Nkind (Parent (T)) = N_Subtype_Declaration
21006 or else (Nkind (Parent (T)) = N_Subtype_Indication
21007 and then Nkind (Parent (Parent (T))) =
21008 N_Subtype_Declaration)))
21010 Error_Msg_N ("invalid use of type before its full declaration", T);
21012 end Check_Incomplete;
21014 -- Start of processing for Process_Subtype
21017 -- Case of no constraints present
21019 if Nkind (S) /= N_Subtype_Indication then
21021 Check_Incomplete (S);
21024 -- Ada 2005 (AI-231): Static check
21026 if Ada_Version >= Ada_2005
21027 and then Present (P)
21028 and then Null_Exclusion_Present (P)
21029 and then Nkind (P) /= N_Access_To_Object_Definition
21030 and then not Is_Access_Type (Entity (S))
21032 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
21035 -- The following is ugly, can't we have a range or even a flag???
21037 May_Have_Null_Exclusion :=
21038 Nkind_In (P, N_Access_Definition,
21039 N_Access_Function_Definition,
21040 N_Access_Procedure_Definition,
21041 N_Access_To_Object_Definition,
21043 N_Component_Definition)
21045 Nkind_In (P, N_Derived_Type_Definition,
21046 N_Discriminant_Specification,
21047 N_Formal_Object_Declaration,
21048 N_Object_Declaration,
21049 N_Object_Renaming_Declaration,
21050 N_Parameter_Specification,
21051 N_Subtype_Declaration);
21053 -- Create an Itype that is a duplicate of Entity (S) but with the
21054 -- null-exclusion attribute.
21056 if May_Have_Null_Exclusion
21057 and then Is_Access_Type (Entity (S))
21058 and then Null_Exclusion_Present (P)
21060 -- No need to check the case of an access to object definition.
21061 -- It is correct to define double not-null pointers.
21064 -- type Not_Null_Int_Ptr is not null access Integer;
21065 -- type Acc is not null access Not_Null_Int_Ptr;
21067 and then Nkind (P) /= N_Access_To_Object_Definition
21069 if Can_Never_Be_Null (Entity (S)) then
21070 case Nkind (Related_Nod) is
21071 when N_Full_Type_Declaration =>
21072 if Nkind (Type_Definition (Related_Nod))
21073 in N_Array_Type_Definition
21077 (Component_Definition
21078 (Type_Definition (Related_Nod)));
21081 Subtype_Indication (Type_Definition (Related_Nod));
21084 when N_Subtype_Declaration =>
21085 Error_Node := Subtype_Indication (Related_Nod);
21087 when N_Object_Declaration =>
21088 Error_Node := Object_Definition (Related_Nod);
21090 when N_Component_Declaration =>
21092 Subtype_Indication (Component_Definition (Related_Nod));
21094 when N_Allocator =>
21095 Error_Node := Expression (Related_Nod);
21098 pragma Assert (False);
21099 Error_Node := Related_Nod;
21103 ("`NOT NULL` not allowed (& already excludes null)",
21109 Create_Null_Excluding_Itype
21111 Related_Nod => P));
21112 Set_Entity (S, Etype (S));
21117 -- Case of constraint present, so that we have an N_Subtype_Indication
21118 -- node (this node is created only if constraints are present).
21121 Find_Type (Subtype_Mark (S));
21123 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
21125 (Nkind (Parent (S)) = N_Subtype_Declaration
21126 and then Is_Itype (Defining_Identifier (Parent (S))))
21128 Check_Incomplete (Subtype_Mark (S));
21132 Subtype_Mark_Id := Entity (Subtype_Mark (S));
21134 -- Explicit subtype declaration case
21136 if Nkind (P) = N_Subtype_Declaration then
21137 Def_Id := Defining_Identifier (P);
21139 -- Explicit derived type definition case
21141 elsif Nkind (P) = N_Derived_Type_Definition then
21142 Def_Id := Defining_Identifier (Parent (P));
21144 -- Implicit case, the Def_Id must be created as an implicit type.
21145 -- The one exception arises in the case of concurrent types, array
21146 -- and access types, where other subsidiary implicit types may be
21147 -- created and must appear before the main implicit type. In these
21148 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
21149 -- has not yet been called to create Def_Id.
21152 if Is_Array_Type (Subtype_Mark_Id)
21153 or else Is_Concurrent_Type (Subtype_Mark_Id)
21154 or else Is_Access_Type (Subtype_Mark_Id)
21158 -- For the other cases, we create a new unattached Itype,
21159 -- and set the indication to ensure it gets attached later.
21163 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21167 -- If the kind of constraint is invalid for this kind of type,
21168 -- then give an error, and then pretend no constraint was given.
21170 if not Is_Valid_Constraint_Kind
21171 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
21174 ("incorrect constraint for this kind of type", Constraint (S));
21176 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
21178 -- Set Ekind of orphan itype, to prevent cascaded errors
21180 if Present (Def_Id) then
21181 Set_Ekind (Def_Id, Ekind (Any_Type));
21184 -- Make recursive call, having got rid of the bogus constraint
21186 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
21189 -- Remaining processing depends on type. Select on Base_Type kind to
21190 -- ensure getting to the concrete type kind in the case of a private
21191 -- subtype (needed when only doing semantic analysis).
21193 case Ekind (Base_Type (Subtype_Mark_Id)) is
21194 when Access_Kind =>
21196 -- If this is a constraint on a class-wide type, discard it.
21197 -- There is currently no way to express a partial discriminant
21198 -- constraint on a type with unknown discriminants. This is
21199 -- a pathology that the ACATS wisely decides not to test.
21201 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
21202 if Comes_From_Source (S) then
21204 ("constraint on class-wide type ignored??",
21208 if Nkind (P) = N_Subtype_Declaration then
21209 Set_Subtype_Indication (P,
21210 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
21213 return Subtype_Mark_Id;
21216 Constrain_Access (Def_Id, S, Related_Nod);
21219 and then Is_Itype (Designated_Type (Def_Id))
21220 and then Nkind (Related_Nod) = N_Subtype_Declaration
21221 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
21223 Build_Itype_Reference
21224 (Designated_Type (Def_Id), Related_Nod);
21228 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
21230 when Decimal_Fixed_Point_Kind =>
21231 Constrain_Decimal (Def_Id, S);
21233 when Enumeration_Kind =>
21234 Constrain_Enumeration (Def_Id, S);
21235 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21237 when Ordinary_Fixed_Point_Kind =>
21238 Constrain_Ordinary_Fixed (Def_Id, S);
21241 Constrain_Float (Def_Id, S);
21243 when Integer_Kind =>
21244 Constrain_Integer (Def_Id, S);
21245 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21247 when Class_Wide_Kind
21248 | E_Incomplete_Type
21252 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21254 if Ekind (Def_Id) = E_Incomplete_Type then
21255 Set_Private_Dependents (Def_Id, New_Elmt_List);
21258 when Private_Kind =>
21259 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21261 -- The base type may be private but Def_Id may be a full view
21264 if Is_Private_Type (Def_Id) then
21265 Set_Private_Dependents (Def_Id, New_Elmt_List);
21268 -- In case of an invalid constraint prevent further processing
21269 -- since the type constructed is missing expected fields.
21271 if Etype (Def_Id) = Any_Type then
21275 -- If the full view is that of a task with discriminants,
21276 -- we must constrain both the concurrent type and its
21277 -- corresponding record type. Otherwise we will just propagate
21278 -- the constraint to the full view, if available.
21280 if Present (Full_View (Subtype_Mark_Id))
21281 and then Has_Discriminants (Subtype_Mark_Id)
21282 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
21285 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21287 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
21288 Constrain_Concurrent (Full_View_Id, S,
21289 Related_Nod, Related_Id, Suffix);
21290 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
21291 Set_Full_View (Def_Id, Full_View_Id);
21293 -- Introduce an explicit reference to the private subtype,
21294 -- to prevent scope anomalies in gigi if first use appears
21295 -- in a nested context, e.g. a later function body.
21296 -- Should this be generated in other contexts than a full
21297 -- type declaration?
21299 if Is_Itype (Def_Id)
21301 Nkind (Parent (P)) = N_Full_Type_Declaration
21303 Build_Itype_Reference (Def_Id, Parent (P));
21307 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
21310 when Concurrent_Kind =>
21311 Constrain_Concurrent (Def_Id, S,
21312 Related_Nod, Related_Id, Suffix);
21315 Error_Msg_N ("invalid subtype mark in subtype indication", S);
21318 -- Size and Convention are always inherited from the base type
21320 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
21321 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
21325 end Process_Subtype;
21327 -----------------------------
21328 -- Record_Type_Declaration --
21329 -----------------------------
21331 procedure Record_Type_Declaration
21336 Def : constant Node_Id := Type_Definition (N);
21337 Is_Tagged : Boolean;
21338 Tag_Comp : Entity_Id;
21341 -- These flags must be initialized before calling Process_Discriminants
21342 -- because this routine makes use of them.
21344 Set_Ekind (T, E_Record_Type);
21346 Init_Size_Align (T);
21347 Set_Interfaces (T, No_Elist);
21348 Set_Stored_Constraint (T, No_Elist);
21349 Set_Default_SSO (T);
21353 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21354 if Limited_Present (Def) then
21355 Check_SPARK_05_Restriction ("limited is not allowed", N);
21358 if Abstract_Present (Def) then
21359 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21362 -- The flag Is_Tagged_Type might have already been set by
21363 -- Find_Type_Name if it detected an error for declaration T. This
21364 -- arises in the case of private tagged types where the full view
21365 -- omits the word tagged.
21368 Tagged_Present (Def)
21369 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21371 Set_Is_Limited_Record (T, Limited_Present (Def));
21374 Set_Is_Tagged_Type (T, True);
21375 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21378 -- Type is abstract if full declaration carries keyword, or if
21379 -- previous partial view did.
21381 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21382 or else Abstract_Present (Def));
21385 Check_SPARK_05_Restriction ("interface is not allowed", N);
21388 Analyze_Interface_Declaration (T, Def);
21390 if Present (Discriminant_Specifications (N)) then
21392 ("interface types cannot have discriminants",
21393 Defining_Identifier
21394 (First (Discriminant_Specifications (N))));
21398 -- First pass: if there are self-referential access components,
21399 -- create the required anonymous access type declarations, and if
21400 -- need be an incomplete type declaration for T itself.
21402 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21404 if Ada_Version >= Ada_2005
21405 and then Present (Interface_List (Def))
21407 Check_Interfaces (N, Def);
21410 Ifaces_List : Elist_Id;
21413 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21414 -- already in the parents.
21418 Ifaces_List => Ifaces_List,
21419 Exclude_Parents => True);
21421 Set_Interfaces (T, Ifaces_List);
21425 -- Records constitute a scope for the component declarations within.
21426 -- The scope is created prior to the processing of these declarations.
21427 -- Discriminants are processed first, so that they are visible when
21428 -- processing the other components. The Ekind of the record type itself
21429 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21431 -- Enter record scope
21435 -- If an incomplete or private type declaration was already given for
21436 -- the type, then this scope already exists, and the discriminants have
21437 -- been declared within. We must verify that the full declaration
21438 -- matches the incomplete one.
21440 Check_Or_Process_Discriminants (N, T, Prev);
21442 Set_Is_Constrained (T, not Has_Discriminants (T));
21443 Set_Has_Delayed_Freeze (T, True);
21445 -- For tagged types add a manually analyzed component corresponding
21446 -- to the component _tag, the corresponding piece of tree will be
21447 -- expanded as part of the freezing actions if it is not a CPP_Class.
21451 -- Do not add the tag unless we are in expansion mode
21453 if Expander_Active then
21454 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21455 Enter_Name (Tag_Comp);
21457 Set_Ekind (Tag_Comp, E_Component);
21458 Set_Is_Tag (Tag_Comp);
21459 Set_Is_Aliased (Tag_Comp);
21460 Set_Etype (Tag_Comp, RTE (RE_Tag));
21461 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21462 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21463 Init_Component_Location (Tag_Comp);
21465 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21466 -- implemented interfaces.
21468 if Has_Interfaces (T) then
21469 Add_Interface_Tag_Components (N, T);
21473 Make_Class_Wide_Type (T);
21474 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21477 -- We must suppress range checks when processing record components in
21478 -- the presence of discriminants, since we don't want spurious checks to
21479 -- be generated during their analysis, but Suppress_Range_Checks flags
21480 -- must be reset the after processing the record definition.
21482 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21483 -- couldn't we just use the normal range check suppression method here.
21484 -- That would seem cleaner ???
21486 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21487 Set_Kill_Range_Checks (T, True);
21488 Record_Type_Definition (Def, Prev);
21489 Set_Kill_Range_Checks (T, False);
21491 Record_Type_Definition (Def, Prev);
21494 -- Exit from record scope
21498 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21499 -- the implemented interfaces and associate them an aliased entity.
21502 and then not Is_Empty_List (Interface_List (Def))
21504 Derive_Progenitor_Subprograms (T, T);
21507 Check_Function_Writable_Actuals (N);
21508 end Record_Type_Declaration;
21510 ----------------------------
21511 -- Record_Type_Definition --
21512 ----------------------------
21514 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21515 Component : Entity_Id;
21516 Ctrl_Components : Boolean := False;
21517 Final_Storage_Only : Boolean;
21521 if Ekind (Prev_T) = E_Incomplete_Type then
21522 T := Full_View (Prev_T);
21527 -- In SPARK, tagged types and type extensions may only be declared in
21528 -- the specification of library unit packages.
21530 if Present (Def) and then Is_Tagged_Type (T) then
21536 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21537 Typ := Parent (Def);
21540 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21541 Typ := Parent (Parent (Def));
21544 Ctxt := Parent (Typ);
21546 if Nkind (Ctxt) = N_Package_Body
21547 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21549 Check_SPARK_05_Restriction
21550 ("type should be defined in package specification", Typ);
21552 elsif Nkind (Ctxt) /= N_Package_Specification
21553 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21555 Check_SPARK_05_Restriction
21556 ("type should be defined in library unit package", Typ);
21561 Final_Storage_Only := not Is_Controlled_Active (T);
21563 -- Ada 2005: Check whether an explicit Limited is present in a derived
21564 -- type declaration.
21566 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21567 and then Limited_Present (Parent (Def))
21569 Set_Is_Limited_Record (T);
21572 -- If the component list of a record type is defined by the reserved
21573 -- word null and there is no discriminant part, then the record type has
21574 -- no components and all records of the type are null records (RM 3.7)
21575 -- This procedure is also called to process the extension part of a
21576 -- record extension, in which case the current scope may have inherited
21580 or else No (Component_List (Def))
21581 or else Null_Present (Component_List (Def))
21583 if not Is_Tagged_Type (T) then
21584 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21588 Analyze_Declarations (Component_Items (Component_List (Def)));
21590 if Present (Variant_Part (Component_List (Def))) then
21591 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21592 Analyze (Variant_Part (Component_List (Def)));
21596 -- After completing the semantic analysis of the record definition,
21597 -- record components, both new and inherited, are accessible. Set their
21598 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21599 -- whose Ekind may be void.
21601 Component := First_Entity (Current_Scope);
21602 while Present (Component) loop
21603 if Ekind (Component) = E_Void
21604 and then not Is_Itype (Component)
21606 Set_Ekind (Component, E_Component);
21607 Init_Component_Location (Component);
21610 Propagate_Concurrent_Flags (T, Etype (Component));
21612 if Ekind (Component) /= E_Component then
21615 -- Do not set Has_Controlled_Component on a class-wide equivalent
21616 -- type. See Make_CW_Equivalent_Type.
21618 elsif not Is_Class_Wide_Equivalent_Type (T)
21619 and then (Has_Controlled_Component (Etype (Component))
21620 or else (Chars (Component) /= Name_uParent
21621 and then Is_Controlled_Active
21622 (Etype (Component))))
21624 Set_Has_Controlled_Component (T, True);
21625 Final_Storage_Only :=
21627 and then Finalize_Storage_Only (Etype (Component));
21628 Ctrl_Components := True;
21631 Next_Entity (Component);
21634 -- A Type is Finalize_Storage_Only only if all its controlled components
21637 if Ctrl_Components then
21638 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21641 -- Place reference to end record on the proper entity, which may
21642 -- be a partial view.
21644 if Present (Def) then
21645 Process_End_Label (Def, 'e', Prev_T);
21647 end Record_Type_Definition;
21649 ------------------------
21650 -- Replace_Components --
21651 ------------------------
21653 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21654 function Process (N : Node_Id) return Traverse_Result;
21660 function Process (N : Node_Id) return Traverse_Result is
21664 if Nkind (N) = N_Discriminant_Specification then
21665 Comp := First_Discriminant (Typ);
21666 while Present (Comp) loop
21667 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21668 Set_Defining_Identifier (N, Comp);
21672 Next_Discriminant (Comp);
21675 elsif Nkind (N) = N_Component_Declaration then
21676 Comp := First_Component (Typ);
21677 while Present (Comp) loop
21678 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21679 Set_Defining_Identifier (N, Comp);
21683 Next_Component (Comp);
21690 procedure Replace is new Traverse_Proc (Process);
21692 -- Start of processing for Replace_Components
21696 end Replace_Components;
21698 -------------------------------
21699 -- Set_Completion_Referenced --
21700 -------------------------------
21702 procedure Set_Completion_Referenced (E : Entity_Id) is
21704 -- If in main unit, mark entity that is a completion as referenced,
21705 -- warnings go on the partial view when needed.
21707 if In_Extended_Main_Source_Unit (E) then
21708 Set_Referenced (E);
21710 end Set_Completion_Referenced;
21712 ---------------------
21713 -- Set_Default_SSO --
21714 ---------------------
21716 procedure Set_Default_SSO (T : Entity_Id) is
21718 case Opt.Default_SSO is
21722 Set_SSO_Set_Low_By_Default (T, True);
21724 Set_SSO_Set_High_By_Default (T, True);
21726 raise Program_Error;
21728 end Set_Default_SSO;
21730 ---------------------
21731 -- Set_Fixed_Range --
21732 ---------------------
21734 -- The range for fixed-point types is complicated by the fact that we
21735 -- do not know the exact end points at the time of the declaration. This
21736 -- is true for three reasons:
21738 -- A size clause may affect the fudging of the end-points.
21739 -- A small clause may affect the values of the end-points.
21740 -- We try to include the end-points if it does not affect the size.
21742 -- This means that the actual end-points must be established at the
21743 -- point when the type is frozen. Meanwhile, we first narrow the range
21744 -- as permitted (so that it will fit if necessary in a small specified
21745 -- size), and then build a range subtree with these narrowed bounds.
21746 -- Set_Fixed_Range constructs the range from real literal values, and
21747 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21749 -- The parent of this range is set to point to the entity so that it is
21750 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21751 -- other scalar types, which are just pointers to the range in the
21752 -- original tree, this would otherwise be an orphan).
21754 -- The tree is left unanalyzed. When the type is frozen, the processing
21755 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21756 -- analyzed, and uses this as an indication that it should complete
21757 -- work on the range (it will know the final small and size values).
21759 procedure Set_Fixed_Range
21765 S : constant Node_Id :=
21767 Low_Bound => Make_Real_Literal (Loc, Lo),
21768 High_Bound => Make_Real_Literal (Loc, Hi));
21770 Set_Scalar_Range (E, S);
21773 -- Before the freeze point, the bounds of a fixed point are universal
21774 -- and carry the corresponding type.
21776 Set_Etype (Low_Bound (S), Universal_Real);
21777 Set_Etype (High_Bound (S), Universal_Real);
21778 end Set_Fixed_Range;
21780 ----------------------------------
21781 -- Set_Scalar_Range_For_Subtype --
21782 ----------------------------------
21784 procedure Set_Scalar_Range_For_Subtype
21785 (Def_Id : Entity_Id;
21789 Kind : constant Entity_Kind := Ekind (Def_Id);
21792 -- Defend against previous error
21794 if Nkind (R) = N_Error then
21798 Set_Scalar_Range (Def_Id, R);
21800 -- We need to link the range into the tree before resolving it so
21801 -- that types that are referenced, including importantly the subtype
21802 -- itself, are properly frozen (Freeze_Expression requires that the
21803 -- expression be properly linked into the tree). Of course if it is
21804 -- already linked in, then we do not disturb the current link.
21806 if No (Parent (R)) then
21807 Set_Parent (R, Def_Id);
21810 -- Reset the kind of the subtype during analysis of the range, to
21811 -- catch possible premature use in the bounds themselves.
21813 Set_Ekind (Def_Id, E_Void);
21814 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21815 Set_Ekind (Def_Id, Kind);
21816 end Set_Scalar_Range_For_Subtype;
21818 --------------------------------------------------------
21819 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21820 --------------------------------------------------------
21822 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21826 -- Make sure set if encountered during Expand_To_Stored_Constraint
21828 Set_Stored_Constraint (E, No_Elist);
21830 -- Give it the right value
21832 if Is_Constrained (E) and then Has_Discriminants (E) then
21833 Set_Stored_Constraint (E,
21834 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21836 end Set_Stored_Constraint_From_Discriminant_Constraint;
21838 -------------------------------------
21839 -- Signed_Integer_Type_Declaration --
21840 -------------------------------------
21842 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21843 Implicit_Base : Entity_Id;
21844 Base_Typ : Entity_Id;
21847 Errs : Boolean := False;
21851 function Can_Derive_From (E : Entity_Id) return Boolean;
21852 -- Determine whether given bounds allow derivation from specified type
21854 procedure Check_Bound (Expr : Node_Id);
21855 -- Check bound to make sure it is integral and static. If not, post
21856 -- appropriate error message and set Errs flag
21858 ---------------------
21859 -- Can_Derive_From --
21860 ---------------------
21862 -- Note we check both bounds against both end values, to deal with
21863 -- strange types like ones with a range of 0 .. -12341234.
21865 function Can_Derive_From (E : Entity_Id) return Boolean is
21866 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21867 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21869 return Lo <= Lo_Val and then Lo_Val <= Hi
21871 Lo <= Hi_Val and then Hi_Val <= Hi;
21872 end Can_Derive_From;
21878 procedure Check_Bound (Expr : Node_Id) is
21880 -- If a range constraint is used as an integer type definition, each
21881 -- bound of the range must be defined by a static expression of some
21882 -- integer type, but the two bounds need not have the same integer
21883 -- type (Negative bounds are allowed.) (RM 3.5.4)
21885 if not Is_Integer_Type (Etype (Expr)) then
21887 ("integer type definition bounds must be of integer type", Expr);
21890 elsif not Is_OK_Static_Expression (Expr) then
21891 Flag_Non_Static_Expr
21892 ("non-static expression used for integer type bound!", Expr);
21895 -- The bounds are folded into literals, and we set their type to be
21896 -- universal, to avoid typing difficulties: we cannot set the type
21897 -- of the literal to the new type, because this would be a forward
21898 -- reference for the back end, and if the original type is user-
21899 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21902 if Is_Entity_Name (Expr) then
21903 Fold_Uint (Expr, Expr_Value (Expr), True);
21906 Set_Etype (Expr, Universal_Integer);
21910 -- Start of processing for Signed_Integer_Type_Declaration
21913 -- Create an anonymous base type
21916 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21918 -- Analyze and check the bounds, they can be of any integer type
21920 Lo := Low_Bound (Def);
21921 Hi := High_Bound (Def);
21923 -- Arbitrarily use Integer as the type if either bound had an error
21925 if Hi = Error or else Lo = Error then
21926 Base_Typ := Any_Integer;
21927 Set_Error_Posted (T, True);
21929 -- Here both bounds are OK expressions
21932 Analyze_And_Resolve (Lo, Any_Integer);
21933 Analyze_And_Resolve (Hi, Any_Integer);
21939 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21940 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21943 -- Find type to derive from
21945 Lo_Val := Expr_Value (Lo);
21946 Hi_Val := Expr_Value (Hi);
21948 if Can_Derive_From (Standard_Short_Short_Integer) then
21949 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21951 elsif Can_Derive_From (Standard_Short_Integer) then
21952 Base_Typ := Base_Type (Standard_Short_Integer);
21954 elsif Can_Derive_From (Standard_Integer) then
21955 Base_Typ := Base_Type (Standard_Integer);
21957 elsif Can_Derive_From (Standard_Long_Integer) then
21958 Base_Typ := Base_Type (Standard_Long_Integer);
21960 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21961 Check_Restriction (No_Long_Long_Integers, Def);
21962 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21965 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21966 Error_Msg_N ("integer type definition bounds out of range", Def);
21967 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21968 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21972 -- Complete both implicit base and declared first subtype entities. The
21973 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21974 -- are not clobbered when the signed integer type acts as a full view of
21977 Set_Etype (Implicit_Base, Base_Typ);
21978 Set_Size_Info (Implicit_Base, Base_Typ);
21979 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21980 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21981 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21983 Set_Ekind (T, E_Signed_Integer_Subtype);
21984 Set_Etype (T, Implicit_Base);
21985 Set_Size_Info (T, Implicit_Base);
21986 Inherit_Rep_Item_Chain (T, Implicit_Base);
21987 Set_Scalar_Range (T, Def);
21988 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21989 Set_Is_Constrained (T);
21990 end Signed_Integer_Type_Declaration;