1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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 Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Itypes; use Itypes;
43 with Layout; use Layout;
45 with Lib.Xref; use Lib.Xref;
46 with Namet; use Namet;
47 with Nmake; use Nmake;
49 with Restrict; use Restrict;
50 with Rident; use Rident;
51 with Rtsfind; use Rtsfind;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Case; use Sem_Case;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch7; use Sem_Ch7;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Ch10; use Sem_Ch10;
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_Prag; use Sem_Prag;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
95 -- Analyze all delayed aspects chained on the contract of object Obj_Id as
96 -- if they appeared at the end of the declarative region. The aspects to be
104 procedure Build_Derived_Type
106 Parent_Type : Entity_Id;
107 Derived_Type : Entity_Id;
108 Is_Completion : Boolean;
109 Derive_Subps : Boolean := True);
110 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
111 -- the N_Full_Type_Declaration node containing the derived type definition.
112 -- Parent_Type is the entity for the parent type in the derived type
113 -- definition and Derived_Type the actual derived type. Is_Completion must
114 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
115 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
116 -- completion of a private type declaration. If Is_Completion is set to
117 -- True, N is the completion of a private type declaration and Derived_Type
118 -- is different from the defining identifier inside N (i.e. Derived_Type /=
119 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
120 -- subprograms should be derived. The only case where this parameter is
121 -- False is when Build_Derived_Type is recursively called to process an
122 -- implicit derived full type for a type derived from a private type (in
123 -- that case the subprograms must only be derived for the private view of
126 -- ??? These flags need a bit of re-examination and re-documentation:
127 -- ??? are they both necessary (both seem related to the recursion)?
129 procedure Build_Derived_Access_Type
131 Parent_Type : Entity_Id;
132 Derived_Type : Entity_Id);
133 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
134 -- create an implicit base if the parent type is constrained or if the
135 -- subtype indication has a constraint.
137 procedure Build_Derived_Array_Type
139 Parent_Type : Entity_Id;
140 Derived_Type : Entity_Id);
141 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
142 -- create an implicit base if the parent type is constrained or if the
143 -- subtype indication has a constraint.
145 procedure Build_Derived_Concurrent_Type
147 Parent_Type : Entity_Id;
148 Derived_Type : Entity_Id);
149 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
150 -- protected type, inherit entries and protected subprograms, check
151 -- legality of discriminant constraints if any.
153 procedure Build_Derived_Enumeration_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id);
157 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
158 -- type, we must create a new list of literals. Types derived from
159 -- Character and [Wide_]Wide_Character are special-cased.
161 procedure Build_Derived_Numeric_Type
163 Parent_Type : Entity_Id;
164 Derived_Type : Entity_Id);
165 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
166 -- an anonymous base type, and propagate constraint to subtype if needed.
168 procedure Build_Derived_Private_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Is_Completion : Boolean;
173 Derive_Subps : Boolean := True);
174 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
175 -- because the parent may or may not have a completion, and the derivation
176 -- may itself be a completion.
178 procedure Build_Derived_Record_Type
180 Parent_Type : Entity_Id;
181 Derived_Type : Entity_Id;
182 Derive_Subps : Boolean := True);
183 -- Subsidiary procedure used for tagged and untagged record types
184 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
185 -- All parameters are as in Build_Derived_Type except that N, in
186 -- addition to being an N_Full_Type_Declaration node, can also be an
187 -- N_Private_Extension_Declaration node. See the definition of this routine
188 -- for much more info. Derive_Subps indicates whether subprograms should be
189 -- derived from the parent type. The only case where Derive_Subps is False
190 -- is for an implicit derived full type for a type derived from a private
191 -- type (see Build_Derived_Type).
193 procedure Build_Discriminal (Discrim : Entity_Id);
194 -- Create the discriminal corresponding to discriminant Discrim, that is
195 -- the parameter corresponding to Discrim to be used in initialization
196 -- procedures for the type where Discrim is a discriminant. Discriminals
197 -- are not used during semantic analysis, and are not fully defined
198 -- entities until expansion. Thus they are not given a scope until
199 -- initialization procedures are built.
201 function Build_Discriminant_Constraints
204 Derived_Def : Boolean := False) return Elist_Id;
205 -- Validate discriminant constraints and return the list of the constraints
206 -- in order of discriminant declarations, where T is the discriminated
207 -- unconstrained type. Def is the N_Subtype_Indication node where the
208 -- discriminants constraints for T are specified. Derived_Def is True
209 -- when building the discriminant constraints in a derived type definition
210 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
211 -- type and Def is the constraint "(xxx)" on T and this routine sets the
212 -- Corresponding_Discriminant field of the discriminants in the derived
213 -- type D to point to the corresponding discriminants in the parent type T.
215 procedure Build_Discriminated_Subtype
219 Related_Nod : Node_Id;
220 For_Access : Boolean := False);
221 -- Subsidiary procedure to Constrain_Discriminated_Type and to
222 -- Process_Incomplete_Dependents. Given
224 -- T (a possibly discriminated base type)
225 -- Def_Id (a very partially built subtype for T),
227 -- the call completes Def_Id to be the appropriate E_*_Subtype.
229 -- The Elist is the list of discriminant constraints if any (it is set
230 -- to No_Elist if T is not a discriminated type, and to an empty list if
231 -- T has discriminants but there are no discriminant constraints). The
232 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
233 -- The For_Access says whether or not this subtype is really constraining
234 -- an access type. That is its sole purpose is the designated type of an
235 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
236 -- is built to avoid freezing T when the access subtype is frozen.
238 function Build_Scalar_Bound
241 Der_T : Entity_Id) return Node_Id;
242 -- The bounds of a derived scalar type are conversions of the bounds of
243 -- the parent type. Optimize the representation if the bounds are literals.
244 -- Needs a more complete spec--what are the parameters exactly, and what
245 -- exactly is the returned value, and how is Bound affected???
247 procedure Build_Underlying_Full_View
251 -- If the completion of a private type is itself derived from a private
252 -- type, or if the full view of a private subtype is itself private, the
253 -- back-end has no way to compute the actual size of this type. We build
254 -- an internal subtype declaration of the proper parent type to convey
255 -- this information. This extra mechanism is needed because a full
256 -- view cannot itself have a full view (it would get clobbered during
259 procedure Check_Access_Discriminant_Requires_Limited
262 -- Check the restriction that the type to which an access discriminant
263 -- belongs must be a concurrent type or a descendant of a type with
264 -- the reserved word 'limited' in its declaration.
266 procedure Check_Anonymous_Access_Components
270 Comp_List : Node_Id);
271 -- Ada 2005 AI-382: an access component in a record definition can refer to
272 -- the enclosing record, in which case it denotes the type itself, and not
273 -- the current instance of the type. We create an anonymous access type for
274 -- the component, and flag it as an access to a component, so accessibility
275 -- checks are properly performed on it. The declaration of the access type
276 -- is placed ahead of that of the record to prevent order-of-elaboration
277 -- circularity issues in Gigi. We create an incomplete type for the record
278 -- declaration, which is the designated type of the anonymous access.
280 procedure Check_Delta_Expression (E : Node_Id);
281 -- Check that the expression represented by E is suitable for use as a
282 -- delta expression, i.e. it is of real type and is static.
284 procedure Check_Digits_Expression (E : Node_Id);
285 -- Check that the expression represented by E is suitable for use as a
286 -- digits expression, i.e. it is of integer type, positive and static.
288 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
289 -- Validate the initialization of an object declaration. T is the required
290 -- type, and Exp is the initialization expression.
292 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
293 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
295 procedure Check_Or_Process_Discriminants
298 Prev : Entity_Id := Empty);
299 -- If N is the full declaration of the completion T of an incomplete or
300 -- private type, check its discriminants (which are already known to be
301 -- conformant with those of the partial view, see Find_Type_Name),
302 -- otherwise process them. Prev is the entity of the partial declaration,
305 procedure Check_Real_Bound (Bound : Node_Id);
306 -- Check given bound for being of real type and static. If not, post an
307 -- appropriate message, and rewrite the bound with the real literal zero.
309 procedure Constant_Redeclaration
313 -- Various checks on legality of full declaration of deferred constant.
314 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
315 -- node. The caller has not yet set any attributes of this entity.
317 function Contain_Interface
319 Ifaces : Elist_Id) return Boolean;
320 -- Ada 2005: Determine whether Iface is present in the list Ifaces
322 procedure Convert_Scalar_Bounds
324 Parent_Type : Entity_Id;
325 Derived_Type : Entity_Id;
327 -- For derived scalar types, convert the bounds in the type definition to
328 -- the derived type, and complete their analysis. Given a constraint of the
329 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
330 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
331 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
332 -- subtype are conversions of those bounds to the derived_type, so that
333 -- their typing is consistent.
335 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
336 -- Copies attributes from array base type T2 to array base type T1. Copies
337 -- only attributes that apply to base types, but not subtypes.
339 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
340 -- Copies attributes from array subtype T2 to array subtype T1. Copies
341 -- attributes that apply to both subtypes and base types.
343 procedure Create_Constrained_Components
347 Constraints : Elist_Id);
348 -- Build the list of entities for a constrained discriminated record
349 -- subtype. If a component depends on a discriminant, replace its subtype
350 -- using the discriminant values in the discriminant constraint. Subt
351 -- is the defining identifier for the subtype whose list of constrained
352 -- entities we will create. Decl_Node is the type declaration node where
353 -- we will attach all the itypes created. Typ is the base discriminated
354 -- type for the subtype Subt. Constraints is the list of discriminant
355 -- constraints for Typ.
357 function Constrain_Component_Type
359 Constrained_Typ : Entity_Id;
360 Related_Node : Node_Id;
362 Constraints : Elist_Id) return Entity_Id;
363 -- Given a discriminated base type Typ, a list of discriminant constraints,
364 -- Constraints, for Typ and a component Comp of Typ, create and return the
365 -- type corresponding to Etype (Comp) where all discriminant references
366 -- are replaced with the corresponding constraint. If Etype (Comp) contains
367 -- no discriminant references then it is returned as-is. Constrained_Typ
368 -- is the final constrained subtype to which the constrained component
369 -- belongs. Related_Node is the node where we attach all created itypes.
371 procedure Constrain_Access
372 (Def_Id : in out Entity_Id;
374 Related_Nod : Node_Id);
375 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
376 -- an anonymous type created for a subtype indication. In that case it is
377 -- created in the procedure and attached to Related_Nod.
379 procedure Constrain_Array
380 (Def_Id : in out Entity_Id;
382 Related_Nod : Node_Id;
383 Related_Id : Entity_Id;
385 -- Apply a list of index constraints to an unconstrained array type. The
386 -- first parameter is the entity for the resulting subtype. A value of
387 -- Empty for Def_Id indicates that an implicit type must be created, but
388 -- creation is delayed (and must be done by this procedure) because other
389 -- subsidiary implicit types must be created first (which is why Def_Id
390 -- is an in/out parameter). The second parameter is a subtype indication
391 -- node for the constrained array to be created (e.g. something of the
392 -- form string (1 .. 10)). Related_Nod gives the place where this type
393 -- has to be inserted in the tree. The Related_Id and Suffix parameters
394 -- are used to build the associated Implicit type name.
396 procedure Constrain_Concurrent
397 (Def_Id : in out Entity_Id;
399 Related_Nod : Node_Id;
400 Related_Id : Entity_Id;
402 -- Apply list of discriminant constraints to an unconstrained concurrent
405 -- SI is the N_Subtype_Indication node containing the constraint and
406 -- the unconstrained type to constrain.
408 -- Def_Id is the entity for the resulting constrained subtype. A value
409 -- of Empty for Def_Id indicates that an implicit type must be created,
410 -- but creation is delayed (and must be done by this procedure) because
411 -- other subsidiary implicit types must be created first (which is why
412 -- Def_Id is an in/out parameter).
414 -- Related_Nod gives the place where this type has to be inserted
417 -- The last two arguments are used to create its external name if needed.
419 function Constrain_Corresponding_Record
420 (Prot_Subt : Entity_Id;
421 Corr_Rec : Entity_Id;
422 Related_Nod : Node_Id) return Entity_Id;
423 -- When constraining a protected type or task type with discriminants,
424 -- constrain the corresponding record with the same discriminant values.
426 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
427 -- Constrain a decimal fixed point type with a digits constraint and/or a
428 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
430 procedure Constrain_Discriminated_Type
433 Related_Nod : Node_Id;
434 For_Access : Boolean := False);
435 -- Process discriminant constraints of composite type. Verify that values
436 -- have been provided for all discriminants, that the original type is
437 -- unconstrained, and that the types of the supplied expressions match
438 -- the discriminant types. The first three parameters are like in routine
439 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
442 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
443 -- Constrain an enumeration type with a range constraint. This is identical
444 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
446 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
447 -- Constrain a floating point type with either a digits constraint
448 -- and/or a range constraint, building a E_Floating_Point_Subtype.
450 procedure Constrain_Index
453 Related_Nod : Node_Id;
454 Related_Id : Entity_Id;
457 -- Process an index constraint S in a constrained array declaration. The
458 -- constraint can be a subtype name, or a range with or without an explicit
459 -- subtype mark. The index is the corresponding index of the unconstrained
460 -- array. The Related_Id and Suffix parameters are used to build the
461 -- associated Implicit type name.
463 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
464 -- Build subtype of a signed or modular integer type
466 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
467 -- Constrain an ordinary fixed point type with a range constraint, and
468 -- build an E_Ordinary_Fixed_Point_Subtype entity.
470 procedure Copy_And_Swap (Priv, Full : Entity_Id);
471 -- Copy the Priv entity into the entity of its full declaration then swap
472 -- the two entities in such a manner that the former private type is now
473 -- seen as a full type.
475 procedure Decimal_Fixed_Point_Type_Declaration
478 -- Create a new decimal fixed point type, and apply the constraint to
479 -- obtain a subtype of this new type.
481 procedure Complete_Private_Subtype
484 Full_Base : Entity_Id;
485 Related_Nod : Node_Id);
486 -- Complete the implicit full view of a private subtype by setting the
487 -- appropriate semantic fields. If the full view of the parent is a record
488 -- type, build constrained components of subtype.
490 procedure Derive_Progenitor_Subprograms
491 (Parent_Type : Entity_Id;
492 Tagged_Type : Entity_Id);
493 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
494 -- operations of progenitors of Tagged_Type, and replace the subsidiary
495 -- subtypes with Tagged_Type, to build the specs of the inherited interface
496 -- primitives. The derived primitives are aliased to those of the
497 -- interface. This routine takes care also of transferring to the full view
498 -- subprograms associated with the partial view of Tagged_Type that cover
499 -- interface primitives.
501 procedure Derived_Standard_Character
503 Parent_Type : Entity_Id;
504 Derived_Type : Entity_Id);
505 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
506 -- derivations from types Standard.Character and Standard.Wide_Character.
508 procedure Derived_Type_Declaration
511 Is_Completion : Boolean);
512 -- Process a derived type declaration. Build_Derived_Type is invoked
513 -- to process the actual derived type definition. Parameters N and
514 -- Is_Completion have the same meaning as in Build_Derived_Type.
515 -- T is the N_Defining_Identifier for the entity defined in the
516 -- N_Full_Type_Declaration node N, that is T is the derived type.
518 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
519 -- Insert each literal in symbol table, as an overloadable identifier. Each
520 -- enumeration type is mapped into a sequence of integers, and each literal
521 -- is defined as a constant with integer value. If any of the literals are
522 -- character literals, the type is a character type, which means that
523 -- strings are legal aggregates for arrays of components of the type.
525 function Expand_To_Stored_Constraint
527 Constraint : Elist_Id) return Elist_Id;
528 -- Given a constraint (i.e. a list of expressions) on the discriminants of
529 -- Typ, expand it into a constraint on the stored discriminants and return
530 -- the new list of expressions constraining the stored discriminants.
532 function Find_Type_Of_Object
534 Related_Nod : Node_Id) return Entity_Id;
535 -- Get type entity for object referenced by Obj_Def, attaching the
536 -- implicit types generated to Related_Nod
538 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
539 -- Create a new float and apply the constraint to obtain subtype of it
541 function Has_Range_Constraint (N : Node_Id) return Boolean;
542 -- Given an N_Subtype_Indication node N, return True if a range constraint
543 -- is present, either directly, or as part of a digits or delta constraint.
544 -- In addition, a digits constraint in the decimal case returns True, since
545 -- it establishes a default range if no explicit range is present.
547 function Inherit_Components
549 Parent_Base : Entity_Id;
550 Derived_Base : Entity_Id;
552 Inherit_Discr : Boolean;
553 Discs : Elist_Id) return Elist_Id;
554 -- Called from Build_Derived_Record_Type to inherit the components of
555 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
556 -- For more information on derived types and component inheritance please
557 -- consult the comment above the body of Build_Derived_Record_Type.
559 -- N is the original derived type declaration
561 -- Is_Tagged is set if we are dealing with tagged types
563 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
564 -- Parent_Base, otherwise no discriminants are inherited.
566 -- Discs gives the list of constraints that apply to Parent_Base in the
567 -- derived type declaration. If Discs is set to No_Elist, then we have
568 -- the following situation:
570 -- type Parent (D1..Dn : ..) is [tagged] record ...;
571 -- type Derived is new Parent [with ...];
573 -- which gets treated as
575 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
577 -- For untagged types the returned value is an association list. The list
578 -- starts from the association (Parent_Base => Derived_Base), and then it
579 -- contains a sequence of the associations of the form
581 -- (Old_Component => New_Component),
583 -- where Old_Component is the Entity_Id of a component in Parent_Base and
584 -- New_Component is the Entity_Id of the corresponding component in
585 -- Derived_Base. For untagged records, this association list is needed when
586 -- copying the record declaration for the derived base. In the tagged case
587 -- the value returned is irrelevant.
589 function Is_Valid_Constraint_Kind
591 Constraint_Kind : Node_Kind) return Boolean;
592 -- Returns True if it is legal to apply the given kind of constraint to the
593 -- given kind of type (index constraint to an array type, for example).
595 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
596 -- Create new modular type. Verify that modulus is in bounds
598 procedure New_Concatenation_Op (Typ : Entity_Id);
599 -- Create an abbreviated declaration for an operator in order to
600 -- materialize concatenation on array types.
602 procedure Ordinary_Fixed_Point_Type_Declaration
605 -- Create a new ordinary fixed point type, and apply the constraint to
606 -- obtain subtype of it.
608 procedure Prepare_Private_Subtype_Completion
610 Related_Nod : Node_Id);
611 -- Id is a subtype of some private type. Creates the full declaration
612 -- associated with Id whenever possible, i.e. when the full declaration
613 -- of the base type is already known. Records each subtype into
614 -- Private_Dependents of the base type.
616 procedure Process_Incomplete_Dependents
620 -- Process all entities that depend on an incomplete type. There include
621 -- subtypes, subprogram types that mention the incomplete type in their
622 -- profiles, and subprogram with access parameters that designate the
625 -- Inc_T is the defining identifier of an incomplete type declaration, its
626 -- Ekind is E_Incomplete_Type.
628 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
630 -- Full_T is N's defining identifier.
632 -- Subtypes of incomplete types with discriminants are completed when the
633 -- parent type is. This is simpler than private subtypes, because they can
634 -- only appear in the same scope, and there is no need to exchange views.
635 -- Similarly, access_to_subprogram types may have a parameter or a return
636 -- type that is an incomplete type, and that must be replaced with the
639 -- If the full type is tagged, subprogram with access parameters that
640 -- designated the incomplete may be primitive operations of the full type,
641 -- and have to be processed accordingly.
643 procedure Process_Real_Range_Specification (Def : Node_Id);
644 -- Given the type definition for a real type, this procedure processes and
645 -- checks the real range specification of this type definition if one is
646 -- present. If errors are found, error messages are posted, and the
647 -- Real_Range_Specification of Def is reset to Empty.
649 procedure Record_Type_Declaration
653 -- Process a record type declaration (for both untagged and tagged
654 -- records). Parameters T and N are exactly like in procedure
655 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
656 -- for this routine. If this is the completion of an incomplete type
657 -- declaration, Prev is the entity of the incomplete declaration, used for
658 -- cross-referencing. Otherwise Prev = T.
660 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
661 -- This routine is used to process the actual record type definition (both
662 -- for untagged and tagged records). Def is a record type definition node.
663 -- This procedure analyzes the components in this record type definition.
664 -- Prev_T is the entity for the enclosing record type. It is provided so
665 -- that its Has_Task flag can be set if any of the component have Has_Task
666 -- set. If the declaration is the completion of an incomplete type
667 -- declaration, Prev_T is the original incomplete type, whose full view is
670 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
671 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
672 -- build a copy of the declaration tree of the parent, and we create
673 -- independently the list of components for the derived type. Semantic
674 -- information uses the component entities, but record representation
675 -- clauses are validated on the declaration tree. This procedure replaces
676 -- discriminants and components in the declaration with those that have
677 -- been created by Inherit_Components.
679 procedure Set_Fixed_Range
684 -- Build a range node with the given bounds and set it as the Scalar_Range
685 -- of the given fixed-point type entity. Loc is the source location used
686 -- for the constructed range. See body for further details.
688 procedure Set_Scalar_Range_For_Subtype
692 -- This routine is used to set the scalar range field for a subtype given
693 -- Def_Id, the entity for the subtype, and R, the range expression for the
694 -- scalar range. Subt provides the parent subtype to be used to analyze,
695 -- resolve, and check the given range.
697 procedure Set_Default_SSO (T : Entity_Id);
698 -- T is the entity for an array or record being declared. This procedure
699 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
700 -- to the setting of Opt.Default_SSO.
702 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
703 -- Create a new signed integer entity, and apply the constraint to obtain
704 -- the required first named subtype of this type.
706 procedure Set_Stored_Constraint_From_Discriminant_Constraint
708 -- E is some record type. This routine computes E's Stored_Constraint
709 -- from its Discriminant_Constraint.
711 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
712 -- Check that an entity in a list of progenitors is an interface,
713 -- emit error otherwise.
715 -----------------------
716 -- Access_Definition --
717 -----------------------
719 function Access_Definition
720 (Related_Nod : Node_Id;
721 N : Node_Id) return Entity_Id
723 Anon_Type : Entity_Id;
724 Anon_Scope : Entity_Id;
725 Desig_Type : Entity_Id;
726 Enclosing_Prot_Type : Entity_Id := Empty;
729 Check_SPARK_Restriction ("access type is not allowed", N);
731 if Is_Entry (Current_Scope)
732 and then Is_Task_Type (Etype (Scope (Current_Scope)))
734 Error_Msg_N ("task entries cannot have access parameters", N);
738 -- Ada 2005: For an object declaration the corresponding anonymous
739 -- type is declared in the current scope.
741 -- If the access definition is the return type of another access to
742 -- function, scope is the current one, because it is the one of the
743 -- current type declaration, except for the pathological case below.
745 if Nkind_In (Related_Nod, N_Object_Declaration,
746 N_Access_Function_Definition)
748 Anon_Scope := Current_Scope;
750 -- A pathological case: function returning access functions that
751 -- return access functions, etc. Each anonymous access type created
752 -- is in the enclosing scope of the outermost function.
759 while Nkind_In (Par, N_Access_Function_Definition,
765 if Nkind (Par) = N_Function_Specification then
766 Anon_Scope := Scope (Defining_Entity (Par));
770 -- For the anonymous function result case, retrieve the scope of the
771 -- function specification's associated entity rather than using the
772 -- current scope. The current scope will be the function itself if the
773 -- formal part is currently being analyzed, but will be the parent scope
774 -- in the case of a parameterless function, and we always want to use
775 -- the function's parent scope. Finally, if the function is a child
776 -- unit, we must traverse the tree to retrieve the proper entity.
778 elsif Nkind (Related_Nod) = N_Function_Specification
779 and then Nkind (Parent (N)) /= N_Parameter_Specification
781 -- If the current scope is a protected type, the anonymous access
782 -- is associated with one of the protected operations, and must
783 -- be available in the scope that encloses the protected declaration.
784 -- Otherwise the type is in the scope enclosing the subprogram.
786 -- If the function has formals, The return type of a subprogram
787 -- declaration is analyzed in the scope of the subprogram (see
788 -- Process_Formals) and thus the protected type, if present, is
789 -- the scope of the current function scope.
791 if Ekind (Current_Scope) = E_Protected_Type then
792 Enclosing_Prot_Type := Current_Scope;
794 elsif Ekind (Current_Scope) = E_Function
795 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
797 Enclosing_Prot_Type := Scope (Current_Scope);
800 if Present (Enclosing_Prot_Type) then
801 Anon_Scope := Scope (Enclosing_Prot_Type);
804 Anon_Scope := Scope (Defining_Entity (Related_Nod));
807 -- For an access type definition, if the current scope is a child
808 -- unit it is the scope of the type.
810 elsif Is_Compilation_Unit (Current_Scope) then
811 Anon_Scope := Current_Scope;
813 -- For access formals, access components, and access discriminants, the
814 -- scope is that of the enclosing declaration,
817 Anon_Scope := Scope (Current_Scope);
822 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
825 and then Ada_Version >= Ada_2005
827 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
830 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
831 -- the corresponding semantic routine
833 if Present (Access_To_Subprogram_Definition (N)) then
835 -- Compiler runtime units are compiled in Ada 2005 mode when building
836 -- the runtime library but must also be compilable in Ada 95 mode
837 -- (when bootstrapping the compiler).
839 Check_Compiler_Unit ("anonymous access to subprogram", N);
841 Access_Subprogram_Declaration
842 (T_Name => Anon_Type,
843 T_Def => Access_To_Subprogram_Definition (N));
845 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
847 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
849 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
852 Set_Can_Use_Internal_Rep
853 (Anon_Type, not Always_Compatible_Rep_On_Target);
855 -- If the anonymous access is associated with a protected operation,
856 -- create a reference to it after the enclosing protected definition
857 -- because the itype will be used in the subsequent bodies.
859 if Ekind (Current_Scope) = E_Protected_Type then
860 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
866 Find_Type (Subtype_Mark (N));
867 Desig_Type := Entity (Subtype_Mark (N));
869 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
870 Set_Etype (Anon_Type, Anon_Type);
872 -- Make sure the anonymous access type has size and alignment fields
873 -- set, as required by gigi. This is necessary in the case of the
874 -- Task_Body_Procedure.
876 if not Has_Private_Component (Desig_Type) then
877 Layout_Type (Anon_Type);
880 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
881 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
882 -- the null value is allowed. In Ada 95 the null value is never allowed.
884 if Ada_Version >= Ada_2005 then
885 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
887 Set_Can_Never_Be_Null (Anon_Type, True);
890 -- The anonymous access type is as public as the discriminated type or
891 -- subprogram that defines it. It is imported (for back-end purposes)
892 -- if the designated type is.
894 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
896 -- Ada 2005 (AI-231): Propagate the access-constant attribute
898 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
900 -- The context is either a subprogram declaration, object declaration,
901 -- or an access discriminant, in a private or a full type declaration.
902 -- In the case of a subprogram, if the designated type is incomplete,
903 -- the operation will be a primitive operation of the full type, to be
904 -- updated subsequently. If the type is imported through a limited_with
905 -- clause, the subprogram is not a primitive operation of the type
906 -- (which is declared elsewhere in some other scope).
908 if Ekind (Desig_Type) = E_Incomplete_Type
909 and then not From_Limited_With (Desig_Type)
910 and then Is_Overloadable (Current_Scope)
912 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
913 Set_Has_Delayed_Freeze (Current_Scope);
916 -- Ada 2005: If the designated type is an interface that may contain
917 -- tasks, create a Master entity for the declaration. This must be done
918 -- before expansion of the full declaration, because the declaration may
919 -- include an expression that is an allocator, whose expansion needs the
920 -- proper Master for the created tasks.
922 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
924 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
926 Build_Class_Wide_Master (Anon_Type);
928 -- Similarly, if the type is an anonymous access that designates
929 -- tasks, create a master entity for it in the current context.
931 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
933 Build_Master_Entity (Defining_Identifier (Related_Nod));
934 Build_Master_Renaming (Anon_Type);
938 -- For a private component of a protected type, it is imperative that
939 -- the back-end elaborate the type immediately after the protected
940 -- declaration, because this type will be used in the declarations
941 -- created for the component within each protected body, so we must
942 -- create an itype reference for it now.
944 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
945 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
947 -- Similarly, if the access definition is the return result of a
948 -- function, create an itype reference for it because it will be used
949 -- within the function body. For a regular function that is not a
950 -- compilation unit, insert reference after the declaration. For a
951 -- protected operation, insert it after the enclosing protected type
952 -- declaration. In either case, do not create a reference for a type
953 -- obtained through a limited_with clause, because this would introduce
954 -- semantic dependencies.
956 -- Similarly, do not create a reference if the designated type is a
957 -- generic formal, because no use of it will reach the backend.
959 elsif Nkind (Related_Nod) = N_Function_Specification
960 and then not From_Limited_With (Desig_Type)
961 and then not Is_Generic_Type (Desig_Type)
963 if Present (Enclosing_Prot_Type) then
964 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
966 elsif Is_List_Member (Parent (Related_Nod))
967 and then Nkind (Parent (N)) /= N_Parameter_Specification
969 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
972 -- Finally, create an itype reference for an object declaration of an
973 -- anonymous access type. This is strictly necessary only for deferred
974 -- constants, but in any case will avoid out-of-scope problems in the
977 elsif Nkind (Related_Nod) = N_Object_Declaration then
978 Build_Itype_Reference (Anon_Type, Related_Nod);
982 end Access_Definition;
984 -----------------------------------
985 -- Access_Subprogram_Declaration --
986 -----------------------------------
988 procedure Access_Subprogram_Declaration
992 procedure Check_For_Premature_Usage (Def : Node_Id);
993 -- Check that type T_Name is not used, directly or recursively, as a
994 -- parameter or a return type in Def. Def is either a subtype, an
995 -- access_definition, or an access_to_subprogram_definition.
997 -------------------------------
998 -- Check_For_Premature_Usage --
999 -------------------------------
1001 procedure Check_For_Premature_Usage (Def : Node_Id) is
1005 -- Check for a subtype mark
1007 if Nkind (Def) in N_Has_Etype then
1008 if Etype (Def) = T_Name then
1010 ("type& cannot be used before end of its declaration", Def);
1013 -- If this is not a subtype, then this is an access_definition
1015 elsif Nkind (Def) = N_Access_Definition then
1016 if Present (Access_To_Subprogram_Definition (Def)) then
1017 Check_For_Premature_Usage
1018 (Access_To_Subprogram_Definition (Def));
1020 Check_For_Premature_Usage (Subtype_Mark (Def));
1023 -- The only cases left are N_Access_Function_Definition and
1024 -- N_Access_Procedure_Definition.
1027 if Present (Parameter_Specifications (Def)) then
1028 Param := First (Parameter_Specifications (Def));
1029 while Present (Param) loop
1030 Check_For_Premature_Usage (Parameter_Type (Param));
1031 Param := Next (Param);
1035 if Nkind (Def) = N_Access_Function_Definition then
1036 Check_For_Premature_Usage (Result_Definition (Def));
1039 end Check_For_Premature_Usage;
1043 Formals : constant List_Id := Parameter_Specifications (T_Def);
1046 Desig_Type : constant Entity_Id :=
1047 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1049 -- Start of processing for Access_Subprogram_Declaration
1052 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1054 -- Associate the Itype node with the inner full-type declaration or
1055 -- subprogram spec or entry body. This is required to handle nested
1056 -- anonymous declarations. For example:
1059 -- (X : access procedure
1060 -- (Y : access procedure
1063 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1064 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1065 N_Private_Type_Declaration,
1066 N_Private_Extension_Declaration,
1067 N_Procedure_Specification,
1068 N_Function_Specification,
1072 Nkind_In (D_Ityp, N_Object_Declaration,
1073 N_Object_Renaming_Declaration,
1074 N_Formal_Object_Declaration,
1075 N_Formal_Type_Declaration,
1076 N_Task_Type_Declaration,
1077 N_Protected_Type_Declaration))
1079 D_Ityp := Parent (D_Ityp);
1080 pragma Assert (D_Ityp /= Empty);
1083 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1085 if Nkind_In (D_Ityp, N_Procedure_Specification,
1086 N_Function_Specification)
1088 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1090 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1091 N_Object_Declaration,
1092 N_Object_Renaming_Declaration,
1093 N_Formal_Type_Declaration)
1095 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1098 if Nkind (T_Def) = N_Access_Function_Definition then
1099 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1101 Acc : constant Node_Id := Result_Definition (T_Def);
1104 if Present (Access_To_Subprogram_Definition (Acc))
1106 Protected_Present (Access_To_Subprogram_Definition (Acc))
1110 Replace_Anonymous_Access_To_Protected_Subprogram
1116 Access_Definition (T_Def, Result_Definition (T_Def)));
1121 Analyze (Result_Definition (T_Def));
1124 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1127 -- If a null exclusion is imposed on the result type, then
1128 -- create a null-excluding itype (an access subtype) and use
1129 -- it as the function's Etype.
1131 if Is_Access_Type (Typ)
1132 and then Null_Exclusion_In_Return_Present (T_Def)
1134 Set_Etype (Desig_Type,
1135 Create_Null_Excluding_Itype
1137 Related_Nod => T_Def,
1138 Scope_Id => Current_Scope));
1141 if From_Limited_With (Typ) then
1143 -- AI05-151: Incomplete types are allowed in all basic
1144 -- declarations, including access to subprograms.
1146 if Ada_Version >= Ada_2012 then
1151 ("illegal use of incomplete type&",
1152 Result_Definition (T_Def), Typ);
1155 elsif Ekind (Current_Scope) = E_Package
1156 and then In_Private_Part (Current_Scope)
1158 if Ekind (Typ) = E_Incomplete_Type then
1159 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1161 elsif Is_Class_Wide_Type (Typ)
1162 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1165 (Desig_Type, Private_Dependents (Etype (Typ)));
1169 Set_Etype (Desig_Type, Typ);
1174 if not (Is_Type (Etype (Desig_Type))) then
1176 ("expect type in function specification",
1177 Result_Definition (T_Def));
1181 Set_Etype (Desig_Type, Standard_Void_Type);
1184 if Present (Formals) then
1185 Push_Scope (Desig_Type);
1187 -- Some special tests here. These special tests can be removed
1188 -- if and when Itypes always have proper parent pointers to their
1191 -- Special test 1) Link defining_identifier of formals. Required by
1192 -- First_Formal to provide its functionality.
1198 F := First (Formals);
1200 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1201 -- when it is part of an unconstrained type and subtype expansion
1202 -- is disabled. To avoid back-end problems with shared profiles,
1203 -- use previous subprogram type as the designated type, and then
1204 -- remove scope added above.
1206 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1208 Set_Etype (T_Name, T_Name);
1209 Init_Size_Align (T_Name);
1210 Set_Directly_Designated_Type (T_Name,
1211 Scope (Defining_Identifier (F)));
1216 while Present (F) loop
1217 if No (Parent (Defining_Identifier (F))) then
1218 Set_Parent (Defining_Identifier (F), F);
1225 Process_Formals (Formals, Parent (T_Def));
1227 -- Special test 2) End_Scope requires that the parent pointer be set
1228 -- to something reasonable, but Itypes don't have parent pointers. So
1229 -- we set it and then unset it ???
1231 Set_Parent (Desig_Type, T_Name);
1233 Set_Parent (Desig_Type, Empty);
1236 -- Check for premature usage of the type being defined
1238 Check_For_Premature_Usage (T_Def);
1240 -- The return type and/or any parameter type may be incomplete. Mark the
1241 -- subprogram_type as depending on the incomplete type, so that it can
1242 -- be updated when the full type declaration is seen. This only applies
1243 -- to incomplete types declared in some enclosing scope, not to limited
1244 -- views from other packages.
1246 -- Prior to Ada 2012, access to functions can only have in_parameters.
1248 if Present (Formals) then
1249 Formal := First_Formal (Desig_Type);
1250 while Present (Formal) loop
1251 if Ekind (Formal) /= E_In_Parameter
1252 and then Nkind (T_Def) = N_Access_Function_Definition
1253 and then Ada_Version < Ada_2012
1255 Error_Msg_N ("functions can only have IN parameters", Formal);
1258 if Ekind (Etype (Formal)) = E_Incomplete_Type
1259 and then In_Open_Scopes (Scope (Etype (Formal)))
1261 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1262 Set_Has_Delayed_Freeze (Desig_Type);
1265 Next_Formal (Formal);
1269 -- Check whether an indirect call without actuals may be possible. This
1270 -- is used when resolving calls whose result is then indexed.
1272 May_Need_Actuals (Desig_Type);
1274 -- If the return type is incomplete, this is legal as long as the type
1275 -- is declared in the current scope and will be completed in it (rather
1276 -- than being part of limited view).
1278 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1279 and then not Has_Delayed_Freeze (Desig_Type)
1280 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1282 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1283 Set_Has_Delayed_Freeze (Desig_Type);
1286 Check_Delayed_Subprogram (Desig_Type);
1288 if Protected_Present (T_Def) then
1289 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1290 Set_Convention (Desig_Type, Convention_Protected);
1292 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1295 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1297 Set_Etype (T_Name, T_Name);
1298 Init_Size_Align (T_Name);
1299 Set_Directly_Designated_Type (T_Name, Desig_Type);
1301 Generate_Reference_To_Formals (T_Name);
1303 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1305 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1307 Check_Restriction (No_Access_Subprograms, T_Def);
1308 end Access_Subprogram_Declaration;
1310 ----------------------------
1311 -- Access_Type_Declaration --
1312 ----------------------------
1314 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1315 P : constant Node_Id := Parent (Def);
1316 S : constant Node_Id := Subtype_Indication (Def);
1318 Full_Desig : Entity_Id;
1321 Check_SPARK_Restriction ("access type is not allowed", Def);
1323 -- Check for permissible use of incomplete type
1325 if Nkind (S) /= N_Subtype_Indication then
1328 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1329 Set_Directly_Designated_Type (T, Entity (S));
1331 Set_Directly_Designated_Type (T,
1332 Process_Subtype (S, P, T, 'P'));
1335 -- If the access definition is of the form: ACCESS NOT NULL ..
1336 -- the subtype indication must be of an access type. Create
1337 -- a null-excluding subtype of it.
1339 if Null_Excluding_Subtype (Def) then
1340 if not Is_Access_Type (Entity (S)) then
1341 Error_Msg_N ("null exclusion must apply to access type", Def);
1345 Loc : constant Source_Ptr := Sloc (S);
1347 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1351 Make_Subtype_Declaration (Loc,
1352 Defining_Identifier => Nam,
1353 Subtype_Indication =>
1354 New_Occurrence_Of (Entity (S), Loc));
1355 Set_Null_Exclusion_Present (Decl);
1356 Insert_Before (Parent (Def), Decl);
1358 Set_Entity (S, Nam);
1364 Set_Directly_Designated_Type (T,
1365 Process_Subtype (S, P, T, 'P'));
1368 if All_Present (Def) or Constant_Present (Def) then
1369 Set_Ekind (T, E_General_Access_Type);
1371 Set_Ekind (T, E_Access_Type);
1374 Full_Desig := Designated_Type (T);
1376 if Base_Type (Full_Desig) = T then
1377 Error_Msg_N ("access type cannot designate itself", S);
1379 -- In Ada 2005, the type may have a limited view through some unit in
1380 -- its own context, allowing the following circularity that cannot be
1381 -- detected earlier.
1383 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1386 ("access type cannot designate its own classwide type", S);
1388 -- Clean up indication of tagged status to prevent cascaded errors
1390 Set_Is_Tagged_Type (T, False);
1395 -- If the type has appeared already in a with_type clause, it is frozen
1396 -- and the pointer size is already set. Else, initialize.
1398 if not From_Limited_With (T) then
1399 Init_Size_Align (T);
1402 -- Note that Has_Task is always false, since the access type itself
1403 -- is not a task type. See Einfo for more description on this point.
1404 -- Exactly the same consideration applies to Has_Controlled_Component
1405 -- and to Has_Protected.
1407 Set_Has_Task (T, False);
1408 Set_Has_Controlled_Component (T, False);
1409 Set_Has_Protected (T, False);
1411 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1412 -- problems where an incomplete view of this entity has been previously
1413 -- established by a limited with and an overlaid version of this field
1414 -- (Stored_Constraint) was initialized for the incomplete view.
1416 -- This reset is performed in most cases except where the access type
1417 -- has been created for the purposes of allocating or deallocating a
1418 -- build-in-place object. Such access types have explicitly set pools
1419 -- and finalization masters.
1421 if No (Associated_Storage_Pool (T)) then
1422 Set_Finalization_Master (T, Empty);
1425 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1428 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1429 Set_Is_Access_Constant (T, Constant_Present (Def));
1430 end Access_Type_Declaration;
1432 ----------------------------------
1433 -- Add_Interface_Tag_Components --
1434 ----------------------------------
1436 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1437 Loc : constant Source_Ptr := Sloc (N);
1441 procedure Add_Tag (Iface : Entity_Id);
1442 -- Add tag for one of the progenitor interfaces
1448 procedure Add_Tag (Iface : Entity_Id) is
1455 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1457 -- This is a reasonable place to propagate predicates
1459 if Has_Predicates (Iface) then
1460 Set_Has_Predicates (Typ);
1464 Make_Component_Definition (Loc,
1465 Aliased_Present => True,
1466 Subtype_Indication =>
1467 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1469 Tag := Make_Temporary (Loc, 'V');
1472 Make_Component_Declaration (Loc,
1473 Defining_Identifier => Tag,
1474 Component_Definition => Def);
1476 Analyze_Component_Declaration (Decl);
1478 Set_Analyzed (Decl);
1479 Set_Ekind (Tag, E_Component);
1481 Set_Is_Aliased (Tag);
1482 Set_Related_Type (Tag, Iface);
1483 Init_Component_Location (Tag);
1485 pragma Assert (Is_Frozen (Iface));
1487 Set_DT_Entry_Count (Tag,
1488 DT_Entry_Count (First_Entity (Iface)));
1490 if No (Last_Tag) then
1493 Insert_After (Last_Tag, Decl);
1498 -- If the ancestor has discriminants we need to give special support
1499 -- to store the offset_to_top value of the secondary dispatch tables.
1500 -- For this purpose we add a supplementary component just after the
1501 -- field that contains the tag associated with each secondary DT.
1503 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1505 Make_Component_Definition (Loc,
1506 Subtype_Indication =>
1507 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1509 Offset := Make_Temporary (Loc, 'V');
1512 Make_Component_Declaration (Loc,
1513 Defining_Identifier => Offset,
1514 Component_Definition => Def);
1516 Analyze_Component_Declaration (Decl);
1518 Set_Analyzed (Decl);
1519 Set_Ekind (Offset, E_Component);
1520 Set_Is_Aliased (Offset);
1521 Set_Related_Type (Offset, Iface);
1522 Init_Component_Location (Offset);
1523 Insert_After (Last_Tag, Decl);
1534 -- Start of processing for Add_Interface_Tag_Components
1537 if not RTE_Available (RE_Interface_Tag) then
1539 ("(Ada 2005) interface types not supported by this run-time!",
1544 if Ekind (Typ) /= E_Record_Type
1545 or else (Is_Concurrent_Record_Type (Typ)
1546 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1547 or else (not Is_Concurrent_Record_Type (Typ)
1548 and then No (Interfaces (Typ))
1549 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1554 -- Find the current last tag
1556 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1557 Ext := Record_Extension_Part (Type_Definition (N));
1559 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1560 Ext := Type_Definition (N);
1565 if not (Present (Component_List (Ext))) then
1566 Set_Null_Present (Ext, False);
1568 Set_Component_List (Ext,
1569 Make_Component_List (Loc,
1570 Component_Items => L,
1571 Null_Present => False));
1573 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1574 L := Component_Items
1576 (Record_Extension_Part
1577 (Type_Definition (N))));
1579 L := Component_Items
1581 (Type_Definition (N)));
1584 -- Find the last tag component
1587 while Present (Comp) loop
1588 if Nkind (Comp) = N_Component_Declaration
1589 and then Is_Tag (Defining_Identifier (Comp))
1598 -- At this point L references the list of components and Last_Tag
1599 -- references the current last tag (if any). Now we add the tag
1600 -- corresponding with all the interfaces that are not implemented
1603 if Present (Interfaces (Typ)) then
1604 Elmt := First_Elmt (Interfaces (Typ));
1605 while Present (Elmt) loop
1606 Add_Tag (Node (Elmt));
1610 end Add_Interface_Tag_Components;
1612 -------------------------------------
1613 -- Add_Internal_Interface_Entities --
1614 -------------------------------------
1616 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1619 Iface_Elmt : Elmt_Id;
1620 Iface_Prim : Entity_Id;
1621 Ifaces_List : Elist_Id;
1622 New_Subp : Entity_Id := Empty;
1624 Restore_Scope : Boolean := False;
1627 pragma Assert (Ada_Version >= Ada_2005
1628 and then Is_Record_Type (Tagged_Type)
1629 and then Is_Tagged_Type (Tagged_Type)
1630 and then Has_Interfaces (Tagged_Type)
1631 and then not Is_Interface (Tagged_Type));
1633 -- Ensure that the internal entities are added to the scope of the type
1635 if Scope (Tagged_Type) /= Current_Scope then
1636 Push_Scope (Scope (Tagged_Type));
1637 Restore_Scope := True;
1640 Collect_Interfaces (Tagged_Type, Ifaces_List);
1642 Iface_Elmt := First_Elmt (Ifaces_List);
1643 while Present (Iface_Elmt) loop
1644 Iface := Node (Iface_Elmt);
1646 -- Originally we excluded here from this processing interfaces that
1647 -- are parents of Tagged_Type because their primitives are located
1648 -- in the primary dispatch table (and hence no auxiliary internal
1649 -- entities are required to handle secondary dispatch tables in such
1650 -- case). However, these auxiliary entities are also required to
1651 -- handle derivations of interfaces in formals of generics (see
1652 -- Derive_Subprograms).
1654 Elmt := First_Elmt (Primitive_Operations (Iface));
1655 while Present (Elmt) loop
1656 Iface_Prim := Node (Elmt);
1658 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1660 Find_Primitive_Covering_Interface
1661 (Tagged_Type => Tagged_Type,
1662 Iface_Prim => Iface_Prim);
1664 if No (Prim) and then Serious_Errors_Detected > 0 then
1668 pragma Assert (Present (Prim));
1670 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1671 -- differs from the name of the interface primitive then it is
1672 -- a private primitive inherited from a parent type. In such
1673 -- case, given that Tagged_Type covers the interface, the
1674 -- inherited private primitive becomes visible. For such
1675 -- purpose we add a new entity that renames the inherited
1676 -- private primitive.
1678 if Chars (Prim) /= Chars (Iface_Prim) then
1679 pragma Assert (Has_Suffix (Prim, 'P'));
1681 (New_Subp => New_Subp,
1682 Parent_Subp => Iface_Prim,
1683 Derived_Type => Tagged_Type,
1684 Parent_Type => Iface);
1685 Set_Alias (New_Subp, Prim);
1686 Set_Is_Abstract_Subprogram
1687 (New_Subp, Is_Abstract_Subprogram (Prim));
1691 (New_Subp => New_Subp,
1692 Parent_Subp => Iface_Prim,
1693 Derived_Type => Tagged_Type,
1694 Parent_Type => Iface);
1696 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1697 -- associated with interface types. These entities are
1698 -- only registered in the list of primitives of its
1699 -- corresponding tagged type because they are only used
1700 -- to fill the contents of the secondary dispatch tables.
1701 -- Therefore they are removed from the homonym chains.
1703 Set_Is_Hidden (New_Subp);
1704 Set_Is_Internal (New_Subp);
1705 Set_Alias (New_Subp, Prim);
1706 Set_Is_Abstract_Subprogram
1707 (New_Subp, Is_Abstract_Subprogram (Prim));
1708 Set_Interface_Alias (New_Subp, Iface_Prim);
1710 -- If the returned type is an interface then propagate it to
1711 -- the returned type. Needed by the thunk to generate the code
1712 -- which displaces "this" to reference the corresponding
1713 -- secondary dispatch table in the returned object.
1715 if Is_Interface (Etype (Iface_Prim)) then
1716 Set_Etype (New_Subp, Etype (Iface_Prim));
1719 -- Internal entities associated with interface types are
1720 -- only registered in the list of primitives of the tagged
1721 -- type. They are only used to fill the contents of the
1722 -- secondary dispatch tables. Therefore they are not needed
1723 -- in the homonym chains.
1725 Remove_Homonym (New_Subp);
1727 -- Hidden entities associated with interfaces must have set
1728 -- the Has_Delay_Freeze attribute to ensure that, in case of
1729 -- locally defined tagged types (or compiling with static
1730 -- dispatch tables generation disabled) the corresponding
1731 -- entry of the secondary dispatch table is filled when
1732 -- such an entity is frozen.
1734 Set_Has_Delayed_Freeze (New_Subp);
1741 Next_Elmt (Iface_Elmt);
1744 if Restore_Scope then
1747 end Add_Internal_Interface_Entities;
1749 -----------------------------------
1750 -- Analyze_Component_Declaration --
1751 -----------------------------------
1753 procedure Analyze_Component_Declaration (N : Node_Id) is
1754 Id : constant Entity_Id := Defining_Identifier (N);
1755 E : constant Node_Id := Expression (N);
1756 Typ : constant Node_Id :=
1757 Subtype_Indication (Component_Definition (N));
1761 function Contains_POC (Constr : Node_Id) return Boolean;
1762 -- Determines whether a constraint uses the discriminant of a record
1763 -- type thus becoming a per-object constraint (POC).
1765 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1766 -- Typ is the type of the current component, check whether this type is
1767 -- a limited type. Used to validate declaration against that of
1768 -- enclosing record.
1774 function Contains_POC (Constr : Node_Id) return Boolean is
1776 -- Prevent cascaded errors
1778 if Error_Posted (Constr) then
1782 case Nkind (Constr) is
1783 when N_Attribute_Reference =>
1784 return Attribute_Name (Constr) = Name_Access
1785 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1787 when N_Discriminant_Association =>
1788 return Denotes_Discriminant (Expression (Constr));
1790 when N_Identifier =>
1791 return Denotes_Discriminant (Constr);
1793 when N_Index_Or_Discriminant_Constraint =>
1798 IDC := First (Constraints (Constr));
1799 while Present (IDC) loop
1801 -- One per-object constraint is sufficient
1803 if Contains_POC (IDC) then
1814 return Denotes_Discriminant (Low_Bound (Constr))
1816 Denotes_Discriminant (High_Bound (Constr));
1818 when N_Range_Constraint =>
1819 return Denotes_Discriminant (Range_Expression (Constr));
1827 ----------------------
1828 -- Is_Known_Limited --
1829 ----------------------
1831 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1832 P : constant Entity_Id := Etype (Typ);
1833 R : constant Entity_Id := Root_Type (Typ);
1836 if Is_Limited_Record (Typ) then
1839 -- If the root type is limited (and not a limited interface)
1840 -- so is the current type
1842 elsif Is_Limited_Record (R)
1843 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1847 -- Else the type may have a limited interface progenitor, but a
1848 -- limited record parent.
1850 elsif R /= P and then Is_Limited_Record (P) then
1856 end Is_Known_Limited;
1858 -- Start of processing for Analyze_Component_Declaration
1861 Generate_Definition (Id);
1864 if Present (Typ) then
1865 T := Find_Type_Of_Object
1866 (Subtype_Indication (Component_Definition (N)), N);
1868 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1869 Check_SPARK_Restriction ("subtype mark required", Typ);
1872 -- Ada 2005 (AI-230): Access Definition case
1875 pragma Assert (Present
1876 (Access_Definition (Component_Definition (N))));
1878 T := Access_Definition
1880 N => Access_Definition (Component_Definition (N)));
1881 Set_Is_Local_Anonymous_Access (T);
1883 -- Ada 2005 (AI-254)
1885 if Present (Access_To_Subprogram_Definition
1886 (Access_Definition (Component_Definition (N))))
1887 and then Protected_Present (Access_To_Subprogram_Definition
1889 (Component_Definition (N))))
1891 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1895 -- If the subtype is a constrained subtype of the enclosing record,
1896 -- (which must have a partial view) the back-end does not properly
1897 -- handle the recursion. Rewrite the component declaration with an
1898 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1899 -- the tree directly because side effects have already been removed from
1900 -- discriminant constraints.
1902 if Ekind (T) = E_Access_Subtype
1903 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1904 and then Comes_From_Source (T)
1905 and then Nkind (Parent (T)) = N_Subtype_Declaration
1906 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1909 (Subtype_Indication (Component_Definition (N)),
1910 New_Copy_Tree (Subtype_Indication (Parent (T))));
1911 T := Find_Type_Of_Object
1912 (Subtype_Indication (Component_Definition (N)), N);
1915 -- If the component declaration includes a default expression, then we
1916 -- check that the component is not of a limited type (RM 3.7(5)),
1917 -- and do the special preanalysis of the expression (see section on
1918 -- "Handling of Default and Per-Object Expressions" in the spec of
1922 Check_SPARK_Restriction ("default expression is not allowed", E);
1923 Preanalyze_Spec_Expression (E, T);
1924 Check_Initialization (T, E);
1926 if Ada_Version >= Ada_2005
1927 and then Ekind (T) = E_Anonymous_Access_Type
1928 and then Etype (E) /= Any_Type
1930 -- Check RM 3.9.2(9): "if the expected type for an expression is
1931 -- an anonymous access-to-specific tagged type, then the object
1932 -- designated by the expression shall not be dynamically tagged
1933 -- unless it is a controlling operand in a call on a dispatching
1936 if Is_Tagged_Type (Directly_Designated_Type (T))
1938 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1940 Ekind (Directly_Designated_Type (Etype (E))) =
1944 ("access to specific tagged type required (RM 3.9.2(9))", E);
1947 -- (Ada 2005: AI-230): Accessibility check for anonymous
1950 if Type_Access_Level (Etype (E)) >
1951 Deepest_Type_Access_Level (T)
1954 ("expression has deeper access level than component " &
1955 "(RM 3.10.2 (12.2))", E);
1958 -- The initialization expression is a reference to an access
1959 -- discriminant. The type of the discriminant is always deeper
1960 -- than any access type.
1962 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1963 and then Is_Entity_Name (E)
1964 and then Ekind (Entity (E)) = E_In_Parameter
1965 and then Present (Discriminal_Link (Entity (E)))
1968 ("discriminant has deeper accessibility level than target",
1974 -- The parent type may be a private view with unknown discriminants,
1975 -- and thus unconstrained. Regular components must be constrained.
1977 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1978 if Is_Class_Wide_Type (T) then
1980 ("class-wide subtype with unknown discriminants" &
1981 " in component declaration",
1982 Subtype_Indication (Component_Definition (N)));
1985 ("unconstrained subtype in component declaration",
1986 Subtype_Indication (Component_Definition (N)));
1989 -- Components cannot be abstract, except for the special case of
1990 -- the _Parent field (case of extending an abstract tagged type)
1992 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1993 Error_Msg_N ("type of a component cannot be abstract", N);
1997 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1999 -- The component declaration may have a per-object constraint, set
2000 -- the appropriate flag in the defining identifier of the subtype.
2002 if Present (Subtype_Indication (Component_Definition (N))) then
2004 Sindic : constant Node_Id :=
2005 Subtype_Indication (Component_Definition (N));
2007 if Nkind (Sindic) = N_Subtype_Indication
2008 and then Present (Constraint (Sindic))
2009 and then Contains_POC (Constraint (Sindic))
2011 Set_Has_Per_Object_Constraint (Id);
2016 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2017 -- out some static checks.
2019 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2020 Null_Exclusion_Static_Checks (N);
2023 -- If this component is private (or depends on a private type), flag the
2024 -- record type to indicate that some operations are not available.
2026 P := Private_Component (T);
2030 -- Check for circular definitions
2032 if P = Any_Type then
2033 Set_Etype (Id, Any_Type);
2035 -- There is a gap in the visibility of operations only if the
2036 -- component type is not defined in the scope of the record type.
2038 elsif Scope (P) = Scope (Current_Scope) then
2041 elsif Is_Limited_Type (P) then
2042 Set_Is_Limited_Composite (Current_Scope);
2045 Set_Is_Private_Composite (Current_Scope);
2050 and then Is_Limited_Type (T)
2051 and then Chars (Id) /= Name_uParent
2052 and then Is_Tagged_Type (Current_Scope)
2054 if Is_Derived_Type (Current_Scope)
2055 and then not Is_Known_Limited (Current_Scope)
2058 ("extension of nonlimited type cannot have limited components",
2061 if Is_Interface (Root_Type (Current_Scope)) then
2063 ("\limitedness is not inherited from limited interface", N);
2064 Error_Msg_N ("\add LIMITED to type indication", N);
2067 Explain_Limited_Type (T, N);
2068 Set_Etype (Id, Any_Type);
2069 Set_Is_Limited_Composite (Current_Scope, False);
2071 elsif not Is_Derived_Type (Current_Scope)
2072 and then not Is_Limited_Record (Current_Scope)
2073 and then not Is_Concurrent_Type (Current_Scope)
2076 ("nonlimited tagged type cannot have limited components", N);
2077 Explain_Limited_Type (T, N);
2078 Set_Etype (Id, Any_Type);
2079 Set_Is_Limited_Composite (Current_Scope, False);
2083 Set_Original_Record_Component (Id, Id);
2085 if Has_Aspects (N) then
2086 Analyze_Aspect_Specifications (N, Id);
2089 Analyze_Dimension (N);
2090 end Analyze_Component_Declaration;
2092 --------------------------
2093 -- Analyze_Declarations --
2094 --------------------------
2096 procedure Analyze_Declarations (L : List_Id) is
2099 procedure Adjust_Decl;
2100 -- Adjust Decl not to include implicit label declarations, since these
2101 -- have strange Sloc values that result in elaboration check problems.
2102 -- (They have the sloc of the label as found in the source, and that
2103 -- is ahead of the current declarative part).
2105 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2106 -- Determine whether Body_Decl denotes the body of a late controlled
2107 -- primitive (either Initialize, Adjust or Finalize). If this is the
2108 -- case, add a proper spec if the body lacks one. The spec is inserted
2109 -- before Body_Decl and immedately analyzed.
2111 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2112 -- Spec_Id is the entity of a package that may define abstract states.
2113 -- If the states have visible refinement, remove the visibility of each
2114 -- constituent at the end of the package body declarations.
2120 procedure Adjust_Decl is
2122 while Present (Prev (Decl))
2123 and then Nkind (Decl) = N_Implicit_Label_Declaration
2129 --------------------------------------
2130 -- Handle_Late_Controlled_Primitive --
2131 --------------------------------------
2133 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2134 Body_Spec : constant Node_Id := Specification (Body_Decl);
2135 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2136 Loc : constant Source_Ptr := Sloc (Body_Id);
2137 Params : constant List_Id :=
2138 Parameter_Specifications (Body_Spec);
2140 Spec_Id : Entity_Id;
2143 -- A dummy variable used to capture the unused result of subprogram
2147 -- Consider only procedure bodies whose name matches one of the three
2148 -- controlled primitives.
2150 if Nkind (Body_Spec) /= N_Procedure_Specification
2151 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2157 -- A controlled primitive must have exactly one formal
2159 elsif List_Length (Params) /= 1 then
2163 Dummy := Analyze_Subprogram_Specification (Body_Spec);
2165 -- The type of the formal must be derived from [Limited_]Controlled
2167 if not Is_Controlled (Etype (Defining_Entity (First (Params)))) then
2171 Spec_Id := Find_Corresponding_Spec (Body_Decl, Post_Error => False);
2173 -- The body has a matching spec, therefore it cannot be a late
2176 if Present (Spec_Id) then
2180 -- At this point the body is known to be a late controlled primitive.
2181 -- Generate a matching spec and insert it before the body. Note the
2182 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2183 -- tree in this case.
2185 Spec := Copy_Separate_Tree (Body_Spec);
2187 -- Ensure that the subprogram declaration does not inherit the null
2188 -- indicator from the body as we now have a proper spec/body pair.
2190 Set_Null_Present (Spec, False);
2192 Insert_Before_And_Analyze (Body_Decl,
2193 Make_Subprogram_Declaration (Loc,
2194 Specification => Spec));
2195 end Handle_Late_Controlled_Primitive;
2197 --------------------------------
2198 -- Remove_Visible_Refinements --
2199 --------------------------------
2201 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2202 State_Elmt : Elmt_Id;
2204 if Present (Abstract_States (Spec_Id)) then
2205 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2206 while Present (State_Elmt) loop
2207 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2208 Next_Elmt (State_Elmt);
2211 end Remove_Visible_Refinements;
2216 Freeze_From : Entity_Id := Empty;
2217 Next_Decl : Node_Id;
2218 Spec_Id : Entity_Id;
2220 Body_Seen : Boolean := False;
2221 -- Flag set when the first body [stub] is encountered
2223 In_Package_Body : Boolean := False;
2224 -- Flag set when the current declaration list belongs to a package body
2226 -- Start of processing for Analyze_Declarations
2229 if Restriction_Check_Required (SPARK_05) then
2230 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2234 while Present (Decl) loop
2236 -- Package spec cannot contain a package declaration in SPARK
2238 if Nkind (Decl) = N_Package_Declaration
2239 and then Nkind (Parent (L)) = N_Package_Specification
2241 Check_SPARK_Restriction
2242 ("package specification cannot contain a package declaration",
2246 -- Complete analysis of declaration
2249 Next_Decl := Next (Decl);
2251 if No (Freeze_From) then
2252 Freeze_From := First_Entity (Current_Scope);
2255 -- At the end of a declarative part, freeze remaining entities
2256 -- declared in it. The end of the visible declarations of package
2257 -- specification is not the end of a declarative part if private
2258 -- declarations are present. The end of a package declaration is a
2259 -- freezing point only if it a library package. A task definition or
2260 -- protected type definition is not a freeze point either. Finally,
2261 -- we do not freeze entities in generic scopes, because there is no
2262 -- code generated for them and freeze nodes will be generated for
2265 -- The end of a package instantiation is not a freeze point, but
2266 -- for now we make it one, because the generic body is inserted
2267 -- (currently) immediately after. Generic instantiations will not
2268 -- be a freeze point once delayed freezing of bodies is implemented.
2269 -- (This is needed in any case for early instantiations ???).
2271 if No (Next_Decl) then
2272 if Nkind_In (Parent (L), N_Component_List,
2274 N_Protected_Definition)
2278 elsif Nkind (Parent (L)) /= N_Package_Specification then
2279 if Nkind (Parent (L)) = N_Package_Body then
2280 Freeze_From := First_Entity (Current_Scope);
2283 -- There may have been several freezing points previously,
2284 -- for example object declarations or subprogram bodies, but
2285 -- at the end of a declarative part we check freezing from
2286 -- the beginning, even though entities may already be frozen,
2287 -- in order to perform visibility checks on delayed aspects.
2290 Freeze_All (First_Entity (Current_Scope), Decl);
2291 Freeze_From := Last_Entity (Current_Scope);
2293 elsif Scope (Current_Scope) /= Standard_Standard
2294 and then not Is_Child_Unit (Current_Scope)
2295 and then No (Generic_Parent (Parent (L)))
2299 elsif L /= Visible_Declarations (Parent (L))
2300 or else No (Private_Declarations (Parent (L)))
2301 or else Is_Empty_List (Private_Declarations (Parent (L)))
2304 Freeze_All (First_Entity (Current_Scope), Decl);
2305 Freeze_From := Last_Entity (Current_Scope);
2308 -- If next node is a body then freeze all types before the body.
2309 -- An exception occurs for some expander-generated bodies. If these
2310 -- are generated at places where in general language rules would not
2311 -- allow a freeze point, then we assume that the expander has
2312 -- explicitly checked that all required types are properly frozen,
2313 -- and we do not cause general freezing here. This special circuit
2314 -- is used when the encountered body is marked as having already
2317 -- In all other cases (bodies that come from source, and expander
2318 -- generated bodies that have not been analyzed yet), freeze all
2319 -- types now. Note that in the latter case, the expander must take
2320 -- care to attach the bodies at a proper place in the tree so as to
2321 -- not cause unwanted freezing at that point.
2323 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2325 -- When a controlled type is frozen, the expander generates stream
2326 -- and controlled type support routines. If the freeze is caused
2327 -- by the stand alone body of Initialize, Adjust and Finalize, the
2328 -- expander will end up using the wrong version of these routines
2329 -- as the body has not been processed yet. To remedy this, detect
2330 -- a late controlled primitive and create a proper spec for it.
2331 -- This ensures that the primitive will override its inherited
2332 -- counterpart before the freeze takes place.
2334 -- If the declaration we just processed is a body, do not attempt
2335 -- to examine Next_Decl as the late primitive idiom can only apply
2336 -- to the first encountered body.
2338 -- The spec of the late primitive is not generated in ASIS mode to
2339 -- ensure a consistent list of primitives that indicates the true
2340 -- semantic structure of the program (which is not relevant when
2341 -- generating executable code.
2343 -- ??? a cleaner approach may be possible and/or this solution
2344 -- could be extended to general-purpose late primitives, TBD.
2346 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2350 if Nkind (Next_Decl) = N_Subprogram_Body then
2351 Handle_Late_Controlled_Primitive (Next_Decl);
2356 Freeze_All (Freeze_From, Decl);
2357 Freeze_From := Last_Entity (Current_Scope);
2363 -- Analyze the contracts of packages and their bodies
2366 Context := Parent (L);
2368 if Nkind (Context) = N_Package_Specification then
2370 -- When a package has private declarations, its contract must be
2371 -- analyzed at the end of the said declarations. This way both the
2372 -- analysis and freeze actions are properly synchronized in case
2373 -- of private type use within the contract.
2375 if L = Private_Declarations (Context) then
2376 Analyze_Package_Contract (Defining_Entity (Context));
2378 -- Otherwise the contract is analyzed at the end of the visible
2381 elsif L = Visible_Declarations (Context)
2382 and then No (Private_Declarations (Context))
2384 Analyze_Package_Contract (Defining_Entity (Context));
2387 elsif Nkind (Context) = N_Package_Body then
2388 In_Package_Body := True;
2389 Spec_Id := Corresponding_Spec (Context);
2391 Analyze_Package_Body_Contract (Defining_Entity (Context));
2395 -- Analyze the contracts of subprogram declarations, subprogram bodies
2396 -- and variables now due to the delayed visibility requirements of their
2400 while Present (Decl) loop
2401 if Nkind (Decl) = N_Object_Declaration then
2402 Analyze_Object_Contract (Defining_Entity (Decl));
2404 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2405 N_Subprogram_Declaration)
2407 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2409 elsif Nkind (Decl) = N_Subprogram_Body then
2410 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2412 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2413 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2419 -- State refinements are visible upto the end the of the package body
2420 -- declarations. Hide the refinements from visibility to restore the
2421 -- original state conditions.
2423 if In_Package_Body then
2424 Remove_Visible_Refinements (Spec_Id);
2426 end Analyze_Declarations;
2428 -----------------------------------
2429 -- Analyze_Full_Type_Declaration --
2430 -----------------------------------
2432 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2433 Def : constant Node_Id := Type_Definition (N);
2434 Def_Id : constant Entity_Id := Defining_Identifier (N);
2438 Is_Remote : constant Boolean :=
2439 (Is_Remote_Types (Current_Scope)
2440 or else Is_Remote_Call_Interface (Current_Scope))
2441 and then not (In_Private_Part (Current_Scope)
2442 or else In_Package_Body (Current_Scope));
2444 procedure Check_Ops_From_Incomplete_Type;
2445 -- If there is a tagged incomplete partial view of the type, traverse
2446 -- the primitives of the incomplete view and change the type of any
2447 -- controlling formals and result to indicate the full view. The
2448 -- primitives will be added to the full type's primitive operations
2449 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2450 -- is called from Process_Incomplete_Dependents).
2452 ------------------------------------
2453 -- Check_Ops_From_Incomplete_Type --
2454 ------------------------------------
2456 procedure Check_Ops_From_Incomplete_Type is
2463 and then Ekind (Prev) = E_Incomplete_Type
2464 and then Is_Tagged_Type (Prev)
2465 and then Is_Tagged_Type (T)
2467 Elmt := First_Elmt (Primitive_Operations (Prev));
2468 while Present (Elmt) loop
2471 Formal := First_Formal (Op);
2472 while Present (Formal) loop
2473 if Etype (Formal) = Prev then
2474 Set_Etype (Formal, T);
2477 Next_Formal (Formal);
2480 if Etype (Op) = Prev then
2487 end Check_Ops_From_Incomplete_Type;
2489 -- Start of processing for Analyze_Full_Type_Declaration
2492 Prev := Find_Type_Name (N);
2494 -- The full view, if present, now points to the current type
2495 -- If there is an incomplete partial view, set a link to it, to
2496 -- simplify the retrieval of primitive operations of the type.
2498 -- Ada 2005 (AI-50217): If the type was previously decorated when
2499 -- imported through a LIMITED WITH clause, it appears as incomplete
2500 -- but has no full view.
2502 if Ekind (Prev) = E_Incomplete_Type and then Present (Full_View (Prev))
2504 T := Full_View (Prev);
2505 Set_Incomplete_View (N, Parent (Prev));
2510 Set_Is_Pure (T, Is_Pure (Current_Scope));
2512 -- We set the flag Is_First_Subtype here. It is needed to set the
2513 -- corresponding flag for the Implicit class-wide-type created
2514 -- during tagged types processing.
2516 Set_Is_First_Subtype (T, True);
2518 -- Only composite types other than array types are allowed to have
2523 -- For derived types, the rule will be checked once we've figured
2524 -- out the parent type.
2526 when N_Derived_Type_Definition =>
2529 -- For record types, discriminants are allowed, unless we are in
2532 when N_Record_Definition =>
2533 if Present (Discriminant_Specifications (N)) then
2534 Check_SPARK_Restriction
2535 ("discriminant type is not allowed",
2537 (First (Discriminant_Specifications (N))));
2541 if Present (Discriminant_Specifications (N)) then
2543 ("elementary or array type cannot have discriminants",
2545 (First (Discriminant_Specifications (N))));
2549 -- Elaborate the type definition according to kind, and generate
2550 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2551 -- already done (this happens during the reanalysis that follows a call
2552 -- to the high level optimizer).
2554 if not Analyzed (T) then
2559 when N_Access_To_Subprogram_Definition =>
2560 Access_Subprogram_Declaration (T, Def);
2562 -- If this is a remote access to subprogram, we must create the
2563 -- equivalent fat pointer type, and related subprograms.
2566 Process_Remote_AST_Declaration (N);
2569 -- Validate categorization rule against access type declaration
2570 -- usually a violation in Pure unit, Shared_Passive unit.
2572 Validate_Access_Type_Declaration (T, N);
2574 when N_Access_To_Object_Definition =>
2575 Access_Type_Declaration (T, Def);
2577 -- Validate categorization rule against access type declaration
2578 -- usually a violation in Pure unit, Shared_Passive unit.
2580 Validate_Access_Type_Declaration (T, N);
2582 -- If we are in a Remote_Call_Interface package and define a
2583 -- RACW, then calling stubs and specific stream attributes
2587 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2589 Add_RACW_Features (Def_Id);
2592 -- Set no strict aliasing flag if config pragma seen
2594 if Opt.No_Strict_Aliasing then
2595 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2598 when N_Array_Type_Definition =>
2599 Array_Type_Declaration (T, Def);
2601 when N_Derived_Type_Definition =>
2602 Derived_Type_Declaration (T, N, T /= Def_Id);
2604 when N_Enumeration_Type_Definition =>
2605 Enumeration_Type_Declaration (T, Def);
2607 when N_Floating_Point_Definition =>
2608 Floating_Point_Type_Declaration (T, Def);
2610 when N_Decimal_Fixed_Point_Definition =>
2611 Decimal_Fixed_Point_Type_Declaration (T, Def);
2613 when N_Ordinary_Fixed_Point_Definition =>
2614 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2616 when N_Signed_Integer_Type_Definition =>
2617 Signed_Integer_Type_Declaration (T, Def);
2619 when N_Modular_Type_Definition =>
2620 Modular_Type_Declaration (T, Def);
2622 when N_Record_Definition =>
2623 Record_Type_Declaration (T, N, Prev);
2625 -- If declaration has a parse error, nothing to elaborate.
2631 raise Program_Error;
2636 if Etype (T) = Any_Type then
2640 -- Controlled type is not allowed in SPARK
2642 if Is_Visibly_Controlled (T) then
2643 Check_SPARK_Restriction ("controlled type is not allowed", N);
2646 -- Some common processing for all types
2648 Set_Depends_On_Private (T, Has_Private_Component (T));
2649 Check_Ops_From_Incomplete_Type;
2651 -- Both the declared entity, and its anonymous base type if one
2652 -- was created, need freeze nodes allocated.
2655 B : constant Entity_Id := Base_Type (T);
2658 -- In the case where the base type differs from the first subtype, we
2659 -- pre-allocate a freeze node, and set the proper link to the first
2660 -- subtype. Freeze_Entity will use this preallocated freeze node when
2661 -- it freezes the entity.
2663 -- This does not apply if the base type is a generic type, whose
2664 -- declaration is independent of the current derived definition.
2666 if B /= T and then not Is_Generic_Type (B) then
2667 Ensure_Freeze_Node (B);
2668 Set_First_Subtype_Link (Freeze_Node (B), T);
2671 -- A type that is imported through a limited_with clause cannot
2672 -- generate any code, and thus need not be frozen. However, an access
2673 -- type with an imported designated type needs a finalization list,
2674 -- which may be referenced in some other package that has non-limited
2675 -- visibility on the designated type. Thus we must create the
2676 -- finalization list at the point the access type is frozen, to
2677 -- prevent unsatisfied references at link time.
2679 if not From_Limited_With (T) or else Is_Access_Type (T) then
2680 Set_Has_Delayed_Freeze (T);
2684 -- Case where T is the full declaration of some private type which has
2685 -- been swapped in Defining_Identifier (N).
2687 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2688 Process_Full_View (N, T, Def_Id);
2690 -- Record the reference. The form of this is a little strange, since
2691 -- the full declaration has been swapped in. So the first parameter
2692 -- here represents the entity to which a reference is made which is
2693 -- the "real" entity, i.e. the one swapped in, and the second
2694 -- parameter provides the reference location.
2696 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2697 -- since we don't want a complaint about the full type being an
2698 -- unwanted reference to the private type
2701 B : constant Boolean := Has_Pragma_Unreferenced (T);
2703 Set_Has_Pragma_Unreferenced (T, False);
2704 Generate_Reference (T, T, 'c');
2705 Set_Has_Pragma_Unreferenced (T, B);
2708 Set_Completion_Referenced (Def_Id);
2710 -- For completion of incomplete type, process incomplete dependents
2711 -- and always mark the full type as referenced (it is the incomplete
2712 -- type that we get for any real reference).
2714 elsif Ekind (Prev) = E_Incomplete_Type then
2715 Process_Incomplete_Dependents (N, T, Prev);
2716 Generate_Reference (Prev, Def_Id, 'c');
2717 Set_Completion_Referenced (Def_Id);
2719 -- If not private type or incomplete type completion, this is a real
2720 -- definition of a new entity, so record it.
2723 Generate_Definition (Def_Id);
2726 if Chars (Scope (Def_Id)) = Name_System
2727 and then Chars (Def_Id) = Name_Address
2728 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2730 Set_Is_Descendent_Of_Address (Def_Id);
2731 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2732 Set_Is_Descendent_Of_Address (Prev);
2735 Set_Optimize_Alignment_Flags (Def_Id);
2736 Check_Eliminated (Def_Id);
2738 -- If the declaration is a completion and aspects are present, apply
2739 -- them to the entity for the type which is currently the partial
2740 -- view, but which is the one that will be frozen.
2742 if Has_Aspects (N) then
2743 if Prev /= Def_Id then
2744 Analyze_Aspect_Specifications (N, Prev);
2746 Analyze_Aspect_Specifications (N, Def_Id);
2749 end Analyze_Full_Type_Declaration;
2751 ----------------------------------
2752 -- Analyze_Incomplete_Type_Decl --
2753 ----------------------------------
2755 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2756 F : constant Boolean := Is_Pure (Current_Scope);
2760 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2762 Generate_Definition (Defining_Identifier (N));
2764 -- Process an incomplete declaration. The identifier must not have been
2765 -- declared already in the scope. However, an incomplete declaration may
2766 -- appear in the private part of a package, for a private type that has
2767 -- already been declared.
2769 -- In this case, the discriminants (if any) must match
2771 T := Find_Type_Name (N);
2773 Set_Ekind (T, E_Incomplete_Type);
2774 Init_Size_Align (T);
2775 Set_Is_First_Subtype (T, True);
2778 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2779 -- incomplete types.
2781 if Tagged_Present (N) then
2782 Set_Is_Tagged_Type (T);
2783 Make_Class_Wide_Type (T);
2784 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2789 Set_Stored_Constraint (T, No_Elist);
2791 if Present (Discriminant_Specifications (N)) then
2792 Process_Discriminants (N);
2797 -- If the type has discriminants, non-trivial subtypes may be
2798 -- declared before the full view of the type. The full views of those
2799 -- subtypes will be built after the full view of the type.
2801 Set_Private_Dependents (T, New_Elmt_List);
2803 end Analyze_Incomplete_Type_Decl;
2805 -----------------------------------
2806 -- Analyze_Interface_Declaration --
2807 -----------------------------------
2809 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2810 CW : constant Entity_Id := Class_Wide_Type (T);
2813 Set_Is_Tagged_Type (T);
2815 Set_Is_Limited_Record (T, Limited_Present (Def)
2816 or else Task_Present (Def)
2817 or else Protected_Present (Def)
2818 or else Synchronized_Present (Def));
2820 -- Type is abstract if full declaration carries keyword, or if previous
2821 -- partial view did.
2823 Set_Is_Abstract_Type (T);
2824 Set_Is_Interface (T);
2826 -- Type is a limited interface if it includes the keyword limited, task,
2827 -- protected, or synchronized.
2829 Set_Is_Limited_Interface
2830 (T, Limited_Present (Def)
2831 or else Protected_Present (Def)
2832 or else Synchronized_Present (Def)
2833 or else Task_Present (Def));
2835 Set_Interfaces (T, New_Elmt_List);
2836 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2838 -- Complete the decoration of the class-wide entity if it was already
2839 -- built (i.e. during the creation of the limited view)
2841 if Present (CW) then
2842 Set_Is_Interface (CW);
2843 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2846 -- Check runtime support for synchronized interfaces
2848 if VM_Target = No_VM
2849 and then (Is_Task_Interface (T)
2850 or else Is_Protected_Interface (T)
2851 or else Is_Synchronized_Interface (T))
2852 and then not RTE_Available (RE_Select_Specific_Data)
2854 Error_Msg_CRT ("synchronized interfaces", T);
2856 end Analyze_Interface_Declaration;
2858 -----------------------------
2859 -- Analyze_Itype_Reference --
2860 -----------------------------
2862 -- Nothing to do. This node is placed in the tree only for the benefit of
2863 -- back end processing, and has no effect on the semantic processing.
2865 procedure Analyze_Itype_Reference (N : Node_Id) is
2867 pragma Assert (Is_Itype (Itype (N)));
2869 end Analyze_Itype_Reference;
2871 --------------------------------
2872 -- Analyze_Number_Declaration --
2873 --------------------------------
2875 procedure Analyze_Number_Declaration (N : Node_Id) is
2876 Id : constant Entity_Id := Defining_Identifier (N);
2877 E : constant Node_Id := Expression (N);
2879 Index : Interp_Index;
2883 Generate_Definition (Id);
2886 -- This is an optimization of a common case of an integer literal
2888 if Nkind (E) = N_Integer_Literal then
2889 Set_Is_Static_Expression (E, True);
2890 Set_Etype (E, Universal_Integer);
2892 Set_Etype (Id, Universal_Integer);
2893 Set_Ekind (Id, E_Named_Integer);
2894 Set_Is_Frozen (Id, True);
2898 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2900 -- Process expression, replacing error by integer zero, to avoid
2901 -- cascaded errors or aborts further along in the processing
2903 -- Replace Error by integer zero, which seems least likely to cause
2907 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2908 Set_Error_Posted (E);
2913 -- Verify that the expression is static and numeric. If
2914 -- the expression is overloaded, we apply the preference
2915 -- rule that favors root numeric types.
2917 if not Is_Overloaded (E) then
2923 Get_First_Interp (E, Index, It);
2924 while Present (It.Typ) loop
2925 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
2926 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2928 if T = Any_Type then
2931 elsif It.Typ = Universal_Real
2932 or else It.Typ = Universal_Integer
2934 -- Choose universal interpretation over any other
2941 Get_Next_Interp (Index, It);
2945 if Is_Integer_Type (T) then
2947 Set_Etype (Id, Universal_Integer);
2948 Set_Ekind (Id, E_Named_Integer);
2950 elsif Is_Real_Type (T) then
2952 -- Because the real value is converted to universal_real, this is a
2953 -- legal context for a universal fixed expression.
2955 if T = Universal_Fixed then
2957 Loc : constant Source_Ptr := Sloc (N);
2958 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2960 New_Occurrence_Of (Universal_Real, Loc),
2961 Expression => Relocate_Node (E));
2968 elsif T = Any_Fixed then
2969 Error_Msg_N ("illegal context for mixed mode operation", E);
2971 -- Expression is of the form : universal_fixed * integer. Try to
2972 -- resolve as universal_real.
2974 T := Universal_Real;
2979 Set_Etype (Id, Universal_Real);
2980 Set_Ekind (Id, E_Named_Real);
2983 Wrong_Type (E, Any_Numeric);
2987 Set_Ekind (Id, E_Constant);
2988 Set_Never_Set_In_Source (Id, True);
2989 Set_Is_True_Constant (Id, True);
2993 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2994 Set_Etype (E, Etype (Id));
2997 if not Is_OK_Static_Expression (E) then
2998 Flag_Non_Static_Expr
2999 ("non-static expression used in number declaration!", E);
3000 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3001 Set_Etype (E, Any_Type);
3003 end Analyze_Number_Declaration;
3005 -----------------------------
3006 -- Analyze_Object_Contract --
3007 -----------------------------
3009 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3010 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3011 AR_Val : Boolean := False;
3012 AW_Val : Boolean := False;
3013 ER_Val : Boolean := False;
3014 EW_Val : Boolean := False;
3016 Seen : Boolean := False;
3019 if Ekind (Obj_Id) = E_Constant then
3021 -- A constant cannot be volatile. This check is only relevant when
3022 -- SPARK_Mode is on as it is not standard Ada legality rule. Do not
3023 -- flag internally-generated constants that map generic formals to
3024 -- actuals in instantiations (SPARK RM 7.1.3(6)).
3027 and then Is_SPARK_Volatile (Obj_Id)
3028 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3030 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3033 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3035 -- The following checks are only relevant when SPARK_Mode is on as
3036 -- they are not standard Ada legality rules.
3038 if SPARK_Mode = On then
3039 if Is_SPARK_Volatile (Obj_Id) then
3041 -- The declaration of a volatile object must appear at the
3042 -- library level (SPARK RM 7.1.3(7), C.6(6)).
3044 if not Is_Library_Level_Entity (Obj_Id) then
3046 ("volatile variable & must be declared at library level",
3049 -- An object of a discriminated type cannot be volatile
3050 -- (SPARK RM C.6(4)).
3052 elsif Has_Discriminants (Obj_Typ) then
3054 ("discriminated object & cannot be volatile", Obj_Id);
3056 -- An object of a tagged type cannot be volatile
3057 -- (SPARK RM C.6(5)).
3059 elsif Is_Tagged_Type (Obj_Typ) then
3060 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3063 -- The object is not volatile
3066 -- A non-volatile object cannot have volatile components
3067 -- (SPARK RM 7.1.3(7)).
3069 if not Is_SPARK_Volatile (Obj_Id)
3070 and then Has_Volatile_Component (Obj_Typ)
3073 ("non-volatile object & cannot have volatile components",
3079 -- Analyze all external properties
3081 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3083 if Present (Prag) then
3084 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3088 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3090 if Present (Prag) then
3091 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3095 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3097 if Present (Prag) then
3098 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3102 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3104 if Present (Prag) then
3105 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3109 -- Verify the mutual interaction of the various external properties
3112 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3115 -- Check whether the lack of indicator Part_Of agrees with the
3116 -- placement of the variable with respect to the state space.
3118 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3121 Check_Missing_Part_Of (Obj_Id);
3124 end Analyze_Object_Contract;
3126 --------------------------------
3127 -- Analyze_Object_Declaration --
3128 --------------------------------
3130 procedure Analyze_Object_Declaration (N : Node_Id) is
3131 Loc : constant Source_Ptr := Sloc (N);
3132 Id : constant Entity_Id := Defining_Identifier (N);
3136 E : Node_Id := Expression (N);
3137 -- E is set to Expression (N) throughout this routine. When
3138 -- Expression (N) is modified, E is changed accordingly.
3140 Prev_Entity : Entity_Id := Empty;
3142 function Count_Tasks (T : Entity_Id) return Uint;
3143 -- This function is called when a non-generic library level object of a
3144 -- task type is declared. Its function is to count the static number of
3145 -- tasks declared within the type (it is only called if Has_Tasks is set
3146 -- for T). As a side effect, if an array of tasks with non-static bounds
3147 -- or a variant record type is encountered, Check_Restrictions is called
3148 -- indicating the count is unknown.
3154 function Count_Tasks (T : Entity_Id) return Uint is
3160 if Is_Task_Type (T) then
3163 elsif Is_Record_Type (T) then
3164 if Has_Discriminants (T) then
3165 Check_Restriction (Max_Tasks, N);
3170 C := First_Component (T);
3171 while Present (C) loop
3172 V := V + Count_Tasks (Etype (C));
3179 elsif Is_Array_Type (T) then
3180 X := First_Index (T);
3181 V := Count_Tasks (Component_Type (T));
3182 while Present (X) loop
3185 if not Is_OK_Static_Subtype (C) then
3186 Check_Restriction (Max_Tasks, N);
3189 V := V * (UI_Max (Uint_0,
3190 Expr_Value (Type_High_Bound (C)) -
3191 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3204 -- Start of processing for Analyze_Object_Declaration
3207 -- There are three kinds of implicit types generated by an
3208 -- object declaration:
3210 -- 1. Those generated by the original Object Definition
3212 -- 2. Those generated by the Expression
3214 -- 3. Those used to constrain the Object Definition with the
3215 -- expression constraints when the definition is unconstrained.
3217 -- They must be generated in this order to avoid order of elaboration
3218 -- issues. Thus the first step (after entering the name) is to analyze
3219 -- the object definition.
3221 if Constant_Present (N) then
3222 Prev_Entity := Current_Entity_In_Scope (Id);
3224 if Present (Prev_Entity)
3226 -- If the homograph is an implicit subprogram, it is overridden
3227 -- by the current declaration.
3229 ((Is_Overloadable (Prev_Entity)
3230 and then Is_Inherited_Operation (Prev_Entity))
3232 -- The current object is a discriminal generated for an entry
3233 -- family index. Even though the index is a constant, in this
3234 -- particular context there is no true constant redeclaration.
3235 -- Enter_Name will handle the visibility.
3238 (Is_Discriminal (Id)
3239 and then Ekind (Discriminal_Link (Id)) =
3240 E_Entry_Index_Parameter)
3242 -- The current object is the renaming for a generic declared
3243 -- within the instance.
3246 (Ekind (Prev_Entity) = E_Package
3247 and then Nkind (Parent (Prev_Entity)) =
3248 N_Package_Renaming_Declaration
3249 and then not Comes_From_Source (Prev_Entity)
3250 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3252 Prev_Entity := Empty;
3256 if Present (Prev_Entity) then
3257 Constant_Redeclaration (Id, N, T);
3259 Generate_Reference (Prev_Entity, Id, 'c');
3260 Set_Completion_Referenced (Id);
3262 if Error_Posted (N) then
3264 -- Type mismatch or illegal redeclaration, Do not analyze
3265 -- expression to avoid cascaded errors.
3267 T := Find_Type_Of_Object (Object_Definition (N), N);
3269 Set_Ekind (Id, E_Variable);
3273 -- In the normal case, enter identifier at the start to catch premature
3274 -- usage in the initialization expression.
3277 Generate_Definition (Id);
3280 Mark_Coextensions (N, Object_Definition (N));
3282 T := Find_Type_Of_Object (Object_Definition (N), N);
3284 if Nkind (Object_Definition (N)) = N_Access_Definition
3286 (Access_To_Subprogram_Definition (Object_Definition (N)))
3287 and then Protected_Present
3288 (Access_To_Subprogram_Definition (Object_Definition (N)))
3290 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3293 if Error_Posted (Id) then
3295 Set_Ekind (Id, E_Variable);
3300 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3301 -- out some static checks
3303 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3305 -- In case of aggregates we must also take care of the correct
3306 -- initialization of nested aggregates bug this is done at the
3307 -- point of the analysis of the aggregate (see sem_aggr.adb).
3309 if Present (Expression (N))
3310 and then Nkind (Expression (N)) = N_Aggregate
3316 Save_Typ : constant Entity_Id := Etype (Id);
3318 Set_Etype (Id, T); -- Temp. decoration for static checks
3319 Null_Exclusion_Static_Checks (N);
3320 Set_Etype (Id, Save_Typ);
3325 -- Object is marked pure if it is in a pure scope
3327 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3329 -- If deferred constant, make sure context is appropriate. We detect
3330 -- a deferred constant as a constant declaration with no expression.
3331 -- A deferred constant can appear in a package body if its completion
3332 -- is by means of an interface pragma.
3334 if Constant_Present (N) and then No (E) then
3336 -- A deferred constant may appear in the declarative part of the
3337 -- following constructs:
3341 -- extended return statements
3344 -- subprogram bodies
3347 -- When declared inside a package spec, a deferred constant must be
3348 -- completed by a full constant declaration or pragma Import. In all
3349 -- other cases, the only proper completion is pragma Import. Extended
3350 -- return statements are flagged as invalid contexts because they do
3351 -- not have a declarative part and so cannot accommodate the pragma.
3353 if Ekind (Current_Scope) = E_Return_Statement then
3355 ("invalid context for deferred constant declaration (RM 7.4)",
3358 ("\declaration requires an initialization expression",
3360 Set_Constant_Present (N, False);
3362 -- In Ada 83, deferred constant must be of private type
3364 elsif not Is_Private_Type (T) then
3365 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3367 ("(Ada 83) deferred constant must be private type", N);
3371 -- If not a deferred constant, then object declaration freezes its type
3374 Check_Fully_Declared (T, N);
3375 Freeze_Before (N, T);
3378 -- If the object was created by a constrained array definition, then
3379 -- set the link in both the anonymous base type and anonymous subtype
3380 -- that are built to represent the array type to point to the object.
3382 if Nkind (Object_Definition (Declaration_Node (Id))) =
3383 N_Constrained_Array_Definition
3385 Set_Related_Array_Object (T, Id);
3386 Set_Related_Array_Object (Base_Type (T), Id);
3389 -- Special checks for protected objects not at library level
3391 if Is_Protected_Type (T)
3392 and then not Is_Library_Level_Entity (Id)
3394 Check_Restriction (No_Local_Protected_Objects, Id);
3396 -- Protected objects with interrupt handlers must be at library level
3398 -- Ada 2005: This test is not needed (and the corresponding clause
3399 -- in the RM is removed) because accessibility checks are sufficient
3400 -- to make handlers not at the library level illegal.
3402 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3403 -- applies to the '95 version of the language as well.
3405 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3407 ("interrupt object can only be declared at library level", Id);
3411 -- The actual subtype of the object is the nominal subtype, unless
3412 -- the nominal one is unconstrained and obtained from the expression.
3416 -- These checks should be performed before the initialization expression
3417 -- is considered, so that the Object_Definition node is still the same
3418 -- as in source code.
3420 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3421 -- shall not be unconstrained. (The only exception to this is the
3422 -- admission of declarations of constants of type String.)
3425 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3427 Check_SPARK_Restriction
3428 ("subtype mark required", Object_Definition (N));
3430 elsif Is_Array_Type (T)
3431 and then not Is_Constrained (T)
3432 and then T /= Standard_String
3434 Check_SPARK_Restriction
3435 ("subtype mark of constrained type expected",
3436 Object_Definition (N));
3439 -- There are no aliased objects in SPARK
3441 if Aliased_Present (N) then
3442 Check_SPARK_Restriction ("aliased object is not allowed", N);
3445 -- Process initialization expression if present and not in error
3447 if Present (E) and then E /= Error then
3449 -- Generate an error in case of CPP class-wide object initialization.
3450 -- Required because otherwise the expansion of the class-wide
3451 -- assignment would try to use 'size to initialize the object
3452 -- (primitive that is not available in CPP tagged types).
3454 if Is_Class_Wide_Type (Act_T)
3456 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3458 (Present (Full_View (Root_Type (Etype (Act_T))))
3460 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3463 ("predefined assignment not available for 'C'P'P tagged types",
3467 Mark_Coextensions (N, E);
3470 -- In case of errors detected in the analysis of the expression,
3471 -- decorate it with the expected type to avoid cascaded errors
3473 if No (Etype (E)) then
3477 -- If an initialization expression is present, then we set the
3478 -- Is_True_Constant flag. It will be reset if this is a variable
3479 -- and it is indeed modified.
3481 Set_Is_True_Constant (Id, True);
3483 -- If we are analyzing a constant declaration, set its completion
3484 -- flag after analyzing and resolving the expression.
3486 if Constant_Present (N) then
3487 Set_Has_Completion (Id);
3490 -- Set type and resolve (type may be overridden later on). Note:
3491 -- Ekind (Id) must still be E_Void at this point so that incorrect
3492 -- early usage within E is properly diagnosed.
3496 -- If the expression is an aggregate we must look ahead to detect
3497 -- the possible presence of an address clause, and defer resolution
3498 -- and expansion of the aggregate to the freeze point of the entity.
3500 if Comes_From_Source (N)
3501 and then Expander_Active
3502 and then Has_Following_Address_Clause (N)
3503 and then Nkind (E) = N_Aggregate
3511 -- No further action needed if E is a call to an inlined function
3512 -- which returns an unconstrained type and it has been expanded into
3513 -- a procedure call. In that case N has been replaced by an object
3514 -- declaration without initializing expression and it has been
3515 -- analyzed (see Expand_Inlined_Call).
3518 and then Expander_Active
3519 and then Nkind (E) = N_Function_Call
3520 and then Nkind (Name (E)) in N_Has_Entity
3521 and then Is_Inlined (Entity (Name (E)))
3522 and then not Is_Constrained (Etype (E))
3523 and then Analyzed (N)
3524 and then No (Expression (N))
3529 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3530 -- node (which was marked already-analyzed), we need to set the type
3531 -- to something other than Any_Access in order to keep gigi happy.
3533 if Etype (E) = Any_Access then
3537 -- If the object is an access to variable, the initialization
3538 -- expression cannot be an access to constant.
3540 if Is_Access_Type (T)
3541 and then not Is_Access_Constant (T)
3542 and then Is_Access_Type (Etype (E))
3543 and then Is_Access_Constant (Etype (E))
3546 ("access to variable cannot be initialized "
3547 & "with an access-to-constant expression", E);
3550 if not Assignment_OK (N) then
3551 Check_Initialization (T, E);
3554 Check_Unset_Reference (E);
3556 -- If this is a variable, then set current value. If this is a
3557 -- declared constant of a scalar type with a static expression,
3558 -- indicate that it is always valid.
3560 if not Constant_Present (N) then
3561 if Compile_Time_Known_Value (E) then
3562 Set_Current_Value (Id, E);
3565 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3566 Set_Is_Known_Valid (Id);
3569 -- Deal with setting of null flags
3571 if Is_Access_Type (T) then
3572 if Known_Non_Null (E) then
3573 Set_Is_Known_Non_Null (Id, True);
3574 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3575 Set_Is_Known_Null (Id, True);
3579 -- Check incorrect use of dynamically tagged expressions
3581 if Is_Tagged_Type (T) then
3582 Check_Dynamically_Tagged_Expression
3588 Apply_Scalar_Range_Check (E, T);
3589 Apply_Static_Length_Check (E, T);
3591 if Nkind (Original_Node (N)) = N_Object_Declaration
3592 and then Comes_From_Source (Original_Node (N))
3594 -- Only call test if needed
3596 and then Restriction_Check_Required (SPARK_05)
3597 and then not Is_SPARK_Initialization_Expr (Original_Node (E))
3599 Check_SPARK_Restriction
3600 ("initialization expression is not appropriate", E);
3604 -- If the No_Streams restriction is set, check that the type of the
3605 -- object is not, and does not contain, any subtype derived from
3606 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3607 -- Has_Stream just for efficiency reasons. There is no point in
3608 -- spending time on a Has_Stream check if the restriction is not set.
3610 if Restriction_Check_Required (No_Streams) then
3611 if Has_Stream (T) then
3612 Check_Restriction (No_Streams, N);
3616 -- Deal with predicate check before we start to do major rewriting. It
3617 -- is OK to initialize and then check the initialized value, since the
3618 -- object goes out of scope if we get a predicate failure. Note that we
3619 -- do this in the analyzer and not the expander because the analyzer
3620 -- does some substantial rewriting in some cases.
3622 -- We need a predicate check if the type has predicates, and if either
3623 -- there is an initializing expression, or for default initialization
3624 -- when we have at least one case of an explicit default initial value
3625 -- and then this is not an internal declaration whose initialization
3626 -- comes later (as for an aggregate expansion).
3628 if not Suppress_Assignment_Checks (N)
3629 and then Present (Predicate_Function (T))
3630 and then not No_Initialization (N)
3634 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3636 -- If the type has a static predicate and the expression is known at
3637 -- compile time, see if the expression satisfies the predicate.
3640 Check_Expression_Against_Static_Predicate (E, T);
3644 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3647 -- Case of unconstrained type
3649 if Is_Indefinite_Subtype (T) then
3651 -- In SPARK, a declaration of unconstrained type is allowed
3652 -- only for constants of type string.
3654 if Is_String_Type (T) and then not Constant_Present (N) then
3655 Check_SPARK_Restriction
3656 ("declaration of object of unconstrained type not allowed", N);
3659 -- Nothing to do in deferred constant case
3661 if Constant_Present (N) and then No (E) then
3664 -- Case of no initialization present
3667 if No_Initialization (N) then
3670 elsif Is_Class_Wide_Type (T) then
3672 ("initialization required in class-wide declaration ", N);
3676 ("unconstrained subtype not allowed (need initialization)",
3677 Object_Definition (N));
3679 if Is_Record_Type (T) and then Has_Discriminants (T) then
3681 ("\provide initial value or explicit discriminant values",
3682 Object_Definition (N));
3685 ("\or give default discriminant values for type&",
3686 Object_Definition (N), T);
3688 elsif Is_Array_Type (T) then
3690 ("\provide initial value or explicit array bounds",
3691 Object_Definition (N));
3695 -- Case of initialization present but in error. Set initial
3696 -- expression as absent (but do not make above complaints)
3698 elsif E = Error then
3699 Set_Expression (N, Empty);
3702 -- Case of initialization present
3705 -- Check restrictions in Ada 83
3707 if not Constant_Present (N) then
3709 -- Unconstrained variables not allowed in Ada 83 mode
3711 if Ada_Version = Ada_83
3712 and then Comes_From_Source (Object_Definition (N))
3715 ("(Ada 83) unconstrained variable not allowed",
3716 Object_Definition (N));
3720 -- Now we constrain the variable from the initializing expression
3722 -- If the expression is an aggregate, it has been expanded into
3723 -- individual assignments. Retrieve the actual type from the
3724 -- expanded construct.
3726 if Is_Array_Type (T)
3727 and then No_Initialization (N)
3728 and then Nkind (Original_Node (E)) = N_Aggregate
3732 -- In case of class-wide interface object declarations we delay
3733 -- the generation of the equivalent record type declarations until
3734 -- its expansion because there are cases in they are not required.
3736 elsif Is_Interface (T) then
3740 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3741 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3744 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3746 if Aliased_Present (N) then
3747 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3750 Freeze_Before (N, Act_T);
3751 Freeze_Before (N, T);
3754 elsif Is_Array_Type (T)
3755 and then No_Initialization (N)
3756 and then Nkind (Original_Node (E)) = N_Aggregate
3758 if not Is_Entity_Name (Object_Definition (N)) then
3760 Check_Compile_Time_Size (Act_T);
3762 if Aliased_Present (N) then
3763 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3767 -- When the given object definition and the aggregate are specified
3768 -- independently, and their lengths might differ do a length check.
3769 -- This cannot happen if the aggregate is of the form (others =>...)
3771 if not Is_Constrained (T) then
3774 elsif Nkind (E) = N_Raise_Constraint_Error then
3776 -- Aggregate is statically illegal. Place back in declaration
3778 Set_Expression (N, E);
3779 Set_No_Initialization (N, False);
3781 elsif T = Etype (E) then
3784 elsif Nkind (E) = N_Aggregate
3785 and then Present (Component_Associations (E))
3786 and then Present (Choices (First (Component_Associations (E))))
3787 and then Nkind (First
3788 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3793 Apply_Length_Check (E, T);
3796 -- If the type is limited unconstrained with defaulted discriminants and
3797 -- there is no expression, then the object is constrained by the
3798 -- defaults, so it is worthwhile building the corresponding subtype.
3800 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3801 and then not Is_Constrained (T)
3802 and then Has_Discriminants (T)
3805 Act_T := Build_Default_Subtype (T, N);
3807 -- Ada 2005: A limited object may be initialized by means of an
3808 -- aggregate. If the type has default discriminants it has an
3809 -- unconstrained nominal type, Its actual subtype will be obtained
3810 -- from the aggregate, and not from the default discriminants.
3815 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3817 elsif Nkind (E) = N_Function_Call
3818 and then Constant_Present (N)
3819 and then Has_Unconstrained_Elements (Etype (E))
3821 -- The back-end has problems with constants of a discriminated type
3822 -- with defaults, if the initial value is a function call. We
3823 -- generate an intermediate temporary that will receive a reference
3824 -- to the result of the call. The initialization expression then
3825 -- becomes a dereference of that temporary.
3827 Remove_Side_Effects (E);
3829 -- If this is a constant declaration of an unconstrained type and
3830 -- the initialization is an aggregate, we can use the subtype of the
3831 -- aggregate for the declared entity because it is immutable.
3833 elsif not Is_Constrained (T)
3834 and then Has_Discriminants (T)
3835 and then Constant_Present (N)
3836 and then not Has_Unchecked_Union (T)
3837 and then Nkind (E) = N_Aggregate
3842 -- Check No_Wide_Characters restriction
3844 Check_Wide_Character_Restriction (T, Object_Definition (N));
3846 -- Indicate this is not set in source. Certainly true for constants, and
3847 -- true for variables so far (will be reset for a variable if and when
3848 -- we encounter a modification in the source).
3850 Set_Never_Set_In_Source (Id, True);
3852 -- Now establish the proper kind and type of the object
3854 if Constant_Present (N) then
3855 Set_Ekind (Id, E_Constant);
3856 Set_Is_True_Constant (Id);
3859 Set_Ekind (Id, E_Variable);
3861 -- A variable is set as shared passive if it appears in a shared
3862 -- passive package, and is at the outer level. This is not done for
3863 -- entities generated during expansion, because those are always
3864 -- manipulated locally.
3866 if Is_Shared_Passive (Current_Scope)
3867 and then Is_Library_Level_Entity (Id)
3868 and then Comes_From_Source (Id)
3870 Set_Is_Shared_Passive (Id);
3871 Check_Shared_Var (Id, T, N);
3874 -- Set Has_Initial_Value if initializing expression present. Note
3875 -- that if there is no initializing expression, we leave the state
3876 -- of this flag unchanged (usually it will be False, but notably in
3877 -- the case of exception choice variables, it will already be true).
3880 Set_Has_Initial_Value (Id, True);
3883 Set_Contract (Id, Make_Contract (Sloc (Id)));
3886 -- Initialize alignment and size and capture alignment setting
3888 Init_Alignment (Id);
3890 Set_Optimize_Alignment_Flags (Id);
3892 -- Deal with aliased case
3894 if Aliased_Present (N) then
3895 Set_Is_Aliased (Id);
3897 -- If the object is aliased and the type is unconstrained with
3898 -- defaulted discriminants and there is no expression, then the
3899 -- object is constrained by the defaults, so it is worthwhile
3900 -- building the corresponding subtype.
3902 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3903 -- unconstrained, then only establish an actual subtype if the
3904 -- nominal subtype is indefinite. In definite cases the object is
3905 -- unconstrained in Ada 2005.
3908 and then Is_Record_Type (T)
3909 and then not Is_Constrained (T)
3910 and then Has_Discriminants (T)
3911 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3913 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3917 -- Now we can set the type of the object
3919 Set_Etype (Id, Act_T);
3921 -- Object is marked to be treated as volatile if type is volatile and
3922 -- we clear the Current_Value setting that may have been set above.
3924 if Treat_As_Volatile (Etype (Id)) then
3925 Set_Treat_As_Volatile (Id);
3926 Set_Current_Value (Id, Empty);
3929 -- Deal with controlled types
3931 if Has_Controlled_Component (Etype (Id))
3932 or else Is_Controlled (Etype (Id))
3934 if not Is_Library_Level_Entity (Id) then
3935 Check_Restriction (No_Nested_Finalization, N);
3937 Validate_Controlled_Object (Id);
3941 if Has_Task (Etype (Id)) then
3942 Check_Restriction (No_Tasking, N);
3944 -- Deal with counting max tasks
3946 -- Nothing to do if inside a generic
3948 if Inside_A_Generic then
3951 -- If library level entity, then count tasks
3953 elsif Is_Library_Level_Entity (Id) then
3954 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3956 -- If not library level entity, then indicate we don't know max
3957 -- tasks and also check task hierarchy restriction and blocking
3958 -- operation (since starting a task is definitely blocking).
3961 Check_Restriction (Max_Tasks, N);
3962 Check_Restriction (No_Task_Hierarchy, N);
3963 Check_Potentially_Blocking_Operation (N);
3966 -- A rather specialized test. If we see two tasks being declared
3967 -- of the same type in the same object declaration, and the task
3968 -- has an entry with an address clause, we know that program error
3969 -- will be raised at run time since we can't have two tasks with
3970 -- entries at the same address.
3972 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3977 E := First_Entity (Etype (Id));
3978 while Present (E) loop
3979 if Ekind (E) = E_Entry
3980 and then Present (Get_Attribute_Definition_Clause
3981 (E, Attribute_Address))
3983 Error_Msg_Warn := SPARK_Mode /= On;
3985 ("more than one task with same entry address<<", N);
3986 Error_Msg_N ("\Program_Error [<<", N);
3988 Make_Raise_Program_Error (Loc,
3989 Reason => PE_Duplicated_Entry_Address));
3999 -- Some simple constant-propagation: if the expression is a constant
4000 -- string initialized with a literal, share the literal. This avoids
4004 and then Is_Entity_Name (E)
4005 and then Ekind (Entity (E)) = E_Constant
4006 and then Base_Type (Etype (E)) = Standard_String
4009 Val : constant Node_Id := Constant_Value (Entity (E));
4011 if Present (Val) and then Nkind (Val) = N_String_Literal then
4012 Rewrite (E, New_Copy (Val));
4017 -- Another optimization: if the nominal subtype is unconstrained and
4018 -- the expression is a function call that returns an unconstrained
4019 -- type, rewrite the declaration as a renaming of the result of the
4020 -- call. The exceptions below are cases where the copy is expected,
4021 -- either by the back end (Aliased case) or by the semantics, as for
4022 -- initializing controlled types or copying tags for classwide types.
4025 and then Nkind (E) = N_Explicit_Dereference
4026 and then Nkind (Original_Node (E)) = N_Function_Call
4027 and then not Is_Library_Level_Entity (Id)
4028 and then not Is_Constrained (Underlying_Type (T))
4029 and then not Is_Aliased (Id)
4030 and then not Is_Class_Wide_Type (T)
4031 and then not Is_Controlled (T)
4032 and then not Has_Controlled_Component (Base_Type (T))
4033 and then Expander_Active
4036 Make_Object_Renaming_Declaration (Loc,
4037 Defining_Identifier => Id,
4038 Access_Definition => Empty,
4039 Subtype_Mark => New_Occurrence_Of
4040 (Base_Type (Etype (Id)), Loc),
4043 Set_Renamed_Object (Id, E);
4045 -- Force generation of debugging information for the constant and for
4046 -- the renamed function call.
4048 Set_Debug_Info_Needed (Id);
4049 Set_Debug_Info_Needed (Entity (Prefix (E)));
4052 if Present (Prev_Entity)
4053 and then Is_Frozen (Prev_Entity)
4054 and then not Error_Posted (Id)
4056 Error_Msg_N ("full constant declaration appears too late", N);
4059 Check_Eliminated (Id);
4061 -- Deal with setting In_Private_Part flag if in private part
4063 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4065 Set_In_Private_Part (Id);
4068 -- Check for violation of No_Local_Timing_Events
4070 if Restriction_Check_Required (No_Local_Timing_Events)
4071 and then not Is_Library_Level_Entity (Id)
4072 and then Is_RTE (Etype (Id), RE_Timing_Event)
4074 Check_Restriction (No_Local_Timing_Events, N);
4078 -- Initialize the refined state of a variable here because this is a
4079 -- common destination for legal and illegal object declarations.
4081 if Ekind (Id) = E_Variable then
4082 Set_Encapsulating_State (Id, Empty);
4085 if Has_Aspects (N) then
4086 Analyze_Aspect_Specifications (N, Id);
4089 Analyze_Dimension (N);
4091 -- Verify whether the object declaration introduces an illegal hidden
4092 -- state within a package subject to a null abstract state.
4094 if Ekind (Id) = E_Variable then
4095 Check_No_Hidden_State (Id);
4097 end Analyze_Object_Declaration;
4099 ---------------------------
4100 -- Analyze_Others_Choice --
4101 ---------------------------
4103 -- Nothing to do for the others choice node itself, the semantic analysis
4104 -- of the others choice will occur as part of the processing of the parent
4106 procedure Analyze_Others_Choice (N : Node_Id) is
4107 pragma Warnings (Off, N);
4110 end Analyze_Others_Choice;
4112 -------------------------------------------
4113 -- Analyze_Private_Extension_Declaration --
4114 -------------------------------------------
4116 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4117 T : constant Entity_Id := Defining_Identifier (N);
4118 Indic : constant Node_Id := Subtype_Indication (N);
4119 Parent_Type : Entity_Id;
4120 Parent_Base : Entity_Id;
4123 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4125 if Is_Non_Empty_List (Interface_List (N)) then
4131 Intf := First (Interface_List (N));
4132 while Present (Intf) loop
4133 T := Find_Type_Of_Subtype_Indic (Intf);
4135 Diagnose_Interface (Intf, T);
4141 Generate_Definition (T);
4143 -- For other than Ada 2012, just enter the name in the current scope
4145 if Ada_Version < Ada_2012 then
4148 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4149 -- case of private type that completes an incomplete type.
4156 Prev := Find_Type_Name (N);
4158 pragma Assert (Prev = T
4159 or else (Ekind (Prev) = E_Incomplete_Type
4160 and then Present (Full_View (Prev))
4161 and then Full_View (Prev) = T));
4165 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4166 Parent_Base := Base_Type (Parent_Type);
4168 if Parent_Type = Any_Type
4169 or else Etype (Parent_Type) = Any_Type
4171 Set_Ekind (T, Ekind (Parent_Type));
4172 Set_Etype (T, Any_Type);
4175 elsif not Is_Tagged_Type (Parent_Type) then
4177 ("parent of type extension must be a tagged type ", Indic);
4180 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4181 Error_Msg_N ("premature derivation of incomplete type", Indic);
4184 elsif Is_Concurrent_Type (Parent_Type) then
4186 ("parent type of a private extension cannot be "
4187 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4189 Set_Etype (T, Any_Type);
4190 Set_Ekind (T, E_Limited_Private_Type);
4191 Set_Private_Dependents (T, New_Elmt_List);
4192 Set_Error_Posted (T);
4196 -- Perhaps the parent type should be changed to the class-wide type's
4197 -- specific type in this case to prevent cascading errors ???
4199 if Is_Class_Wide_Type (Parent_Type) then
4201 ("parent of type extension must not be a class-wide type", Indic);
4205 if (not Is_Package_Or_Generic_Package (Current_Scope)
4206 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4207 or else In_Private_Part (Current_Scope)
4210 Error_Msg_N ("invalid context for private extension", N);
4213 -- Set common attributes
4215 Set_Is_Pure (T, Is_Pure (Current_Scope));
4216 Set_Scope (T, Current_Scope);
4217 Set_Ekind (T, E_Record_Type_With_Private);
4218 Init_Size_Align (T);
4219 Set_Default_SSO (T);
4221 Set_Etype (T, Parent_Base);
4222 Set_Has_Task (T, Has_Task (Parent_Base));
4223 Set_Has_Protected (T, Has_Task (Parent_Base));
4225 Set_Convention (T, Convention (Parent_Type));
4226 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4227 Set_Is_First_Subtype (T);
4228 Make_Class_Wide_Type (T);
4230 if Unknown_Discriminants_Present (N) then
4231 Set_Discriminant_Constraint (T, No_Elist);
4234 Build_Derived_Record_Type (N, Parent_Type, T);
4236 -- Propagate inherited invariant information. The new type has
4237 -- invariants, if the parent type has inheritable invariants,
4238 -- and these invariants can in turn be inherited.
4240 if Has_Inheritable_Invariants (Parent_Type) then
4241 Set_Has_Inheritable_Invariants (T);
4242 Set_Has_Invariants (T);
4245 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4246 -- synchronized formal derived type.
4248 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4249 Set_Is_Limited_Record (T);
4251 -- Formal derived type case
4253 if Is_Generic_Type (T) then
4255 -- The parent must be a tagged limited type or a synchronized
4258 if (not Is_Tagged_Type (Parent_Type)
4259 or else not Is_Limited_Type (Parent_Type))
4261 (not Is_Interface (Parent_Type)
4262 or else not Is_Synchronized_Interface (Parent_Type))
4264 Error_Msg_NE ("parent type of & must be tagged limited " &
4265 "or synchronized", N, T);
4268 -- The progenitors (if any) must be limited or synchronized
4271 if Present (Interfaces (T)) then
4274 Iface_Elmt : Elmt_Id;
4277 Iface_Elmt := First_Elmt (Interfaces (T));
4278 while Present (Iface_Elmt) loop
4279 Iface := Node (Iface_Elmt);
4281 if not Is_Limited_Interface (Iface)
4282 and then not Is_Synchronized_Interface (Iface)
4284 Error_Msg_NE ("progenitor & must be limited " &
4285 "or synchronized", N, Iface);
4288 Next_Elmt (Iface_Elmt);
4293 -- Regular derived extension, the parent must be a limited or
4294 -- synchronized interface.
4297 if not Is_Interface (Parent_Type)
4298 or else (not Is_Limited_Interface (Parent_Type)
4299 and then not Is_Synchronized_Interface (Parent_Type))
4302 ("parent type of & must be limited interface", N, T);
4306 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4307 -- extension with a synchronized parent must be explicitly declared
4308 -- synchronized, because the full view will be a synchronized type.
4309 -- This must be checked before the check for limited types below,
4310 -- to ensure that types declared limited are not allowed to extend
4311 -- synchronized interfaces.
4313 elsif Is_Interface (Parent_Type)
4314 and then Is_Synchronized_Interface (Parent_Type)
4315 and then not Synchronized_Present (N)
4318 ("private extension of& must be explicitly synchronized",
4321 elsif Limited_Present (N) then
4322 Set_Is_Limited_Record (T);
4324 if not Is_Limited_Type (Parent_Type)
4326 (not Is_Interface (Parent_Type)
4327 or else not Is_Limited_Interface (Parent_Type))
4329 Error_Msg_NE ("parent type& of limited extension must be limited",
4335 if Has_Aspects (N) then
4336 Analyze_Aspect_Specifications (N, T);
4338 end Analyze_Private_Extension_Declaration;
4340 ---------------------------------
4341 -- Analyze_Subtype_Declaration --
4342 ---------------------------------
4344 procedure Analyze_Subtype_Declaration
4346 Skip : Boolean := False)
4348 Id : constant Entity_Id := Defining_Identifier (N);
4350 R_Checks : Check_Result;
4353 Generate_Definition (Id);
4354 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4355 Init_Size_Align (Id);
4357 -- The following guard condition on Enter_Name is to handle cases where
4358 -- the defining identifier has already been entered into the scope but
4359 -- the declaration as a whole needs to be analyzed.
4361 -- This case in particular happens for derived enumeration types. The
4362 -- derived enumeration type is processed as an inserted enumeration type
4363 -- declaration followed by a rewritten subtype declaration. The defining
4364 -- identifier, however, is entered into the name scope very early in the
4365 -- processing of the original type declaration and therefore needs to be
4366 -- avoided here, when the created subtype declaration is analyzed. (See
4367 -- Build_Derived_Types)
4369 -- This also happens when the full view of a private type is derived
4370 -- type with constraints. In this case the entity has been introduced
4371 -- in the private declaration.
4373 -- Finally this happens in some complex cases when validity checks are
4374 -- enabled, where the same subtype declaration may be analyzed twice.
4375 -- This can happen if the subtype is created by the pre-analysis of
4376 -- an attribute tht gives the range of a loop statement, and the loop
4377 -- itself appears within an if_statement that will be rewritten during
4381 or else (Present (Etype (Id))
4382 and then (Is_Private_Type (Etype (Id))
4383 or else Is_Task_Type (Etype (Id))
4384 or else Is_Rewrite_Substitution (N)))
4388 elsif Current_Entity (Id) = Id then
4395 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4397 -- Class-wide equivalent types of records with unknown discriminants
4398 -- involve the generation of an itype which serves as the private view
4399 -- of a constrained record subtype. In such cases the base type of the
4400 -- current subtype we are processing is the private itype. Use the full
4401 -- of the private itype when decorating various attributes.
4404 and then Is_Private_Type (T)
4405 and then Present (Full_View (T))
4410 -- Inherit common attributes
4412 Set_Is_Volatile (Id, Is_Volatile (T));
4413 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4414 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4415 Set_Convention (Id, Convention (T));
4417 -- If ancestor has predicates then so does the subtype, and in addition
4418 -- we must delay the freeze to properly arrange predicate inheritance.
4420 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4421 -- in which T = ID, so the above tests and assignments do nothing???
4423 if Has_Predicates (T)
4424 or else (Present (Ancestor_Subtype (T))
4425 and then Has_Predicates (Ancestor_Subtype (T)))
4427 Set_Has_Predicates (Id);
4428 Set_Has_Delayed_Freeze (Id);
4431 -- Subtype of Boolean cannot have a constraint in SPARK
4433 if Is_Boolean_Type (T)
4434 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4436 Check_SPARK_Restriction
4437 ("subtype of Boolean cannot have constraint", N);
4440 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4442 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4448 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4449 One_Cstr := First (Constraints (Cstr));
4450 while Present (One_Cstr) loop
4452 -- Index or discriminant constraint in SPARK must be a
4456 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4458 Check_SPARK_Restriction
4459 ("subtype mark required", One_Cstr);
4461 -- String subtype must have a lower bound of 1 in SPARK.
4462 -- Note that we do not need to test for the non-static case
4463 -- here, since that was already taken care of in
4464 -- Process_Range_Expr_In_Decl.
4466 elsif Base_Type (T) = Standard_String then
4467 Get_Index_Bounds (One_Cstr, Low, High);
4469 if Is_OK_Static_Expression (Low)
4470 and then Expr_Value (Low) /= 1
4472 Check_SPARK_Restriction
4473 ("String subtype must have lower bound of 1", N);
4483 -- In the case where there is no constraint given in the subtype
4484 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4485 -- semantic attributes must be established here.
4487 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4488 Set_Etype (Id, Base_Type (T));
4490 -- Subtype of unconstrained array without constraint is not allowed
4493 if Is_Array_Type (T) and then not Is_Constrained (T) then
4494 Check_SPARK_Restriction
4495 ("subtype of unconstrained array must have constraint", N);
4500 Set_Ekind (Id, E_Array_Subtype);
4501 Copy_Array_Subtype_Attributes (Id, T);
4503 when Decimal_Fixed_Point_Kind =>
4504 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4505 Set_Digits_Value (Id, Digits_Value (T));
4506 Set_Delta_Value (Id, Delta_Value (T));
4507 Set_Scale_Value (Id, Scale_Value (T));
4508 Set_Small_Value (Id, Small_Value (T));
4509 Set_Scalar_Range (Id, Scalar_Range (T));
4510 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4511 Set_Is_Constrained (Id, Is_Constrained (T));
4512 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4513 Set_RM_Size (Id, RM_Size (T));
4515 when Enumeration_Kind =>
4516 Set_Ekind (Id, E_Enumeration_Subtype);
4517 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4518 Set_Scalar_Range (Id, Scalar_Range (T));
4519 Set_Is_Character_Type (Id, Is_Character_Type (T));
4520 Set_Is_Constrained (Id, Is_Constrained (T));
4521 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4522 Set_RM_Size (Id, RM_Size (T));
4524 when Ordinary_Fixed_Point_Kind =>
4525 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4526 Set_Scalar_Range (Id, Scalar_Range (T));
4527 Set_Small_Value (Id, Small_Value (T));
4528 Set_Delta_Value (Id, Delta_Value (T));
4529 Set_Is_Constrained (Id, Is_Constrained (T));
4530 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4531 Set_RM_Size (Id, RM_Size (T));
4534 Set_Ekind (Id, E_Floating_Point_Subtype);
4535 Set_Scalar_Range (Id, Scalar_Range (T));
4536 Set_Digits_Value (Id, Digits_Value (T));
4537 Set_Is_Constrained (Id, Is_Constrained (T));
4539 when Signed_Integer_Kind =>
4540 Set_Ekind (Id, E_Signed_Integer_Subtype);
4541 Set_Scalar_Range (Id, Scalar_Range (T));
4542 Set_Is_Constrained (Id, Is_Constrained (T));
4543 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4544 Set_RM_Size (Id, RM_Size (T));
4546 when Modular_Integer_Kind =>
4547 Set_Ekind (Id, E_Modular_Integer_Subtype);
4548 Set_Scalar_Range (Id, Scalar_Range (T));
4549 Set_Is_Constrained (Id, Is_Constrained (T));
4550 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4551 Set_RM_Size (Id, RM_Size (T));
4553 when Class_Wide_Kind =>
4554 Set_Ekind (Id, E_Class_Wide_Subtype);
4555 Set_First_Entity (Id, First_Entity (T));
4556 Set_Last_Entity (Id, Last_Entity (T));
4557 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4558 Set_Cloned_Subtype (Id, T);
4559 Set_Is_Tagged_Type (Id, True);
4560 Set_Has_Unknown_Discriminants
4563 if Ekind (T) = E_Class_Wide_Subtype then
4564 Set_Equivalent_Type (Id, Equivalent_Type (T));
4567 when E_Record_Type | E_Record_Subtype =>
4568 Set_Ekind (Id, E_Record_Subtype);
4570 if Ekind (T) = E_Record_Subtype
4571 and then Present (Cloned_Subtype (T))
4573 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4575 Set_Cloned_Subtype (Id, T);
4578 Set_First_Entity (Id, First_Entity (T));
4579 Set_Last_Entity (Id, Last_Entity (T));
4580 Set_Has_Discriminants (Id, Has_Discriminants (T));
4581 Set_Is_Constrained (Id, Is_Constrained (T));
4582 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4583 Set_Has_Implicit_Dereference
4584 (Id, Has_Implicit_Dereference (T));
4585 Set_Has_Unknown_Discriminants
4586 (Id, Has_Unknown_Discriminants (T));
4588 if Has_Discriminants (T) then
4589 Set_Discriminant_Constraint
4590 (Id, Discriminant_Constraint (T));
4591 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4593 elsif Has_Unknown_Discriminants (Id) then
4594 Set_Discriminant_Constraint (Id, No_Elist);
4597 if Is_Tagged_Type (T) then
4598 Set_Is_Tagged_Type (Id);
4599 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4600 Set_Direct_Primitive_Operations
4601 (Id, Direct_Primitive_Operations (T));
4602 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4604 if Is_Interface (T) then
4605 Set_Is_Interface (Id);
4606 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4610 when Private_Kind =>
4611 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4612 Set_Has_Discriminants (Id, Has_Discriminants (T));
4613 Set_Is_Constrained (Id, Is_Constrained (T));
4614 Set_First_Entity (Id, First_Entity (T));
4615 Set_Last_Entity (Id, Last_Entity (T));
4616 Set_Private_Dependents (Id, New_Elmt_List);
4617 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4618 Set_Has_Implicit_Dereference
4619 (Id, Has_Implicit_Dereference (T));
4620 Set_Has_Unknown_Discriminants
4621 (Id, Has_Unknown_Discriminants (T));
4622 Set_Known_To_Have_Preelab_Init
4623 (Id, Known_To_Have_Preelab_Init (T));
4625 if Is_Tagged_Type (T) then
4626 Set_Is_Tagged_Type (Id);
4627 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4628 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4629 Set_Direct_Primitive_Operations (Id,
4630 Direct_Primitive_Operations (T));
4633 -- In general the attributes of the subtype of a private type
4634 -- are the attributes of the partial view of parent. However,
4635 -- the full view may be a discriminated type, and the subtype
4636 -- must share the discriminant constraint to generate correct
4637 -- calls to initialization procedures.
4639 if Has_Discriminants (T) then
4640 Set_Discriminant_Constraint
4641 (Id, Discriminant_Constraint (T));
4642 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4644 elsif Present (Full_View (T))
4645 and then Has_Discriminants (Full_View (T))
4647 Set_Discriminant_Constraint
4648 (Id, Discriminant_Constraint (Full_View (T)));
4649 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4651 -- This would seem semantically correct, but apparently
4652 -- generates spurious errors about missing components ???
4654 -- Set_Has_Discriminants (Id);
4657 Prepare_Private_Subtype_Completion (Id, N);
4659 -- If this is the subtype of a constrained private type with
4660 -- discriminants that has got a full view and we also have
4661 -- built a completion just above, show that the completion
4662 -- is a clone of the full view to the back-end.
4664 if Has_Discriminants (T)
4665 and then not Has_Unknown_Discriminants (T)
4666 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4667 and then Present (Full_View (T))
4668 and then Present (Full_View (Id))
4670 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4674 Set_Ekind (Id, E_Access_Subtype);
4675 Set_Is_Constrained (Id, Is_Constrained (T));
4676 Set_Is_Access_Constant
4677 (Id, Is_Access_Constant (T));
4678 Set_Directly_Designated_Type
4679 (Id, Designated_Type (T));
4680 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4682 -- A Pure library_item must not contain the declaration of a
4683 -- named access type, except within a subprogram, generic
4684 -- subprogram, task unit, or protected unit, or if it has
4685 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4687 if Comes_From_Source (Id)
4688 and then In_Pure_Unit
4689 and then not In_Subprogram_Task_Protected_Unit
4690 and then not No_Pool_Assigned (Id)
4693 ("named access types not allowed in pure unit", N);
4696 when Concurrent_Kind =>
4697 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4698 Set_Corresponding_Record_Type (Id,
4699 Corresponding_Record_Type (T));
4700 Set_First_Entity (Id, First_Entity (T));
4701 Set_First_Private_Entity (Id, First_Private_Entity (T));
4702 Set_Has_Discriminants (Id, Has_Discriminants (T));
4703 Set_Is_Constrained (Id, Is_Constrained (T));
4704 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4705 Set_Last_Entity (Id, Last_Entity (T));
4707 if Has_Discriminants (T) then
4708 Set_Discriminant_Constraint (Id,
4709 Discriminant_Constraint (T));
4710 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4713 when E_Incomplete_Type =>
4714 if Ada_Version >= Ada_2005 then
4716 -- In Ada 2005 an incomplete type can be explicitly tagged:
4717 -- propagate indication.
4719 Set_Ekind (Id, E_Incomplete_Subtype);
4720 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4721 Set_Private_Dependents (Id, New_Elmt_List);
4723 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
4724 -- incomplete type visible through a limited with clause.
4726 if From_Limited_With (T)
4727 and then Present (Non_Limited_View (T))
4729 Set_From_Limited_With (Id);
4730 Set_Non_Limited_View (Id, Non_Limited_View (T));
4732 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4733 -- to the private dependents of the original incomplete
4734 -- type for future transformation.
4737 Append_Elmt (Id, Private_Dependents (T));
4740 -- If the subtype name denotes an incomplete type an error
4741 -- was already reported by Process_Subtype.
4744 Set_Etype (Id, Any_Type);
4748 raise Program_Error;
4752 if Etype (Id) = Any_Type then
4756 -- Some common processing on all types
4758 Set_Size_Info (Id, T);
4759 Set_First_Rep_Item (Id, First_Rep_Item (T));
4761 -- If the parent type is a generic actual, so is the subtype. This may
4762 -- happen in a nested instance. Why Comes_From_Source test???
4764 if not Comes_From_Source (N) then
4765 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
4770 Set_Is_Immediately_Visible (Id, True);
4771 Set_Depends_On_Private (Id, Has_Private_Component (T));
4772 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4774 if Is_Interface (T) then
4775 Set_Is_Interface (Id);
4778 if Present (Generic_Parent_Type (N))
4780 (Nkind (Parent (Generic_Parent_Type (N))) /=
4781 N_Formal_Type_Declaration
4783 (Formal_Type_Definition (Parent (Generic_Parent_Type (N)))) /=
4784 N_Formal_Private_Type_Definition)
4786 if Is_Tagged_Type (Id) then
4788 -- If this is a generic actual subtype for a synchronized type,
4789 -- the primitive operations are those of the corresponding record
4790 -- for which there is a separate subtype declaration.
4792 if Is_Concurrent_Type (Id) then
4794 elsif Is_Class_Wide_Type (Id) then
4795 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4797 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4800 elsif Scope (Etype (Id)) /= Standard_Standard then
4801 Derive_Subprograms (Generic_Parent_Type (N), Id);
4805 if Is_Private_Type (T) and then Present (Full_View (T)) then
4806 Conditional_Delay (Id, Full_View (T));
4808 -- The subtypes of components or subcomponents of protected types
4809 -- do not need freeze nodes, which would otherwise appear in the
4810 -- wrong scope (before the freeze node for the protected type). The
4811 -- proper subtypes are those of the subcomponents of the corresponding
4814 elsif Ekind (Scope (Id)) /= E_Protected_Type
4815 and then Present (Scope (Scope (Id))) -- error defense
4816 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4818 Conditional_Delay (Id, T);
4821 -- Check that Constraint_Error is raised for a scalar subtype indication
4822 -- when the lower or upper bound of a non-null range lies outside the
4823 -- range of the type mark.
4825 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4826 if Is_Scalar_Type (Etype (Id))
4827 and then Scalar_Range (Id) /=
4828 Scalar_Range (Etype (Subtype_Mark
4829 (Subtype_Indication (N))))
4833 Etype (Subtype_Mark (Subtype_Indication (N))));
4835 -- In the array case, check compatibility for each index
4837 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
4839 -- This really should be a subprogram that finds the indications
4843 Subt_Index : Node_Id := First_Index (Id);
4844 Target_Index : Node_Id :=
4846 (Subtype_Mark (Subtype_Indication (N))));
4847 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4850 while Present (Subt_Index) loop
4851 if ((Nkind (Subt_Index) = N_Identifier
4852 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4853 or else Nkind (Subt_Index) = N_Subtype_Indication)
4855 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4858 Target_Typ : constant Entity_Id :=
4859 Etype (Target_Index);
4863 (Scalar_Range (Etype (Subt_Index)),
4866 Defining_Identifier (N));
4868 -- Reset Has_Dynamic_Range_Check on the subtype to
4869 -- prevent elision of the index check due to a dynamic
4870 -- check generated for a preceding index (needed since
4871 -- Insert_Range_Checks tries to avoid generating
4872 -- redundant checks on a given declaration).
4874 Set_Has_Dynamic_Range_Check (N, False);
4880 Sloc (Defining_Identifier (N)));
4882 -- Record whether this index involved a dynamic check
4885 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4889 Next_Index (Subt_Index);
4890 Next_Index (Target_Index);
4893 -- Finally, mark whether the subtype involves dynamic checks
4895 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4900 -- Make sure that generic actual types are properly frozen. The subtype
4901 -- is marked as a generic actual type when the enclosing instance is
4902 -- analyzed, so here we identify the subtype from the tree structure.
4905 and then Is_Generic_Actual_Type (Id)
4906 and then In_Instance
4907 and then not Comes_From_Source (N)
4908 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4909 and then Is_Frozen (T)
4911 Freeze_Before (N, Id);
4914 Set_Optimize_Alignment_Flags (Id);
4915 Check_Eliminated (Id);
4918 if Has_Aspects (N) then
4919 Analyze_Aspect_Specifications (N, Id);
4922 Analyze_Dimension (N);
4923 end Analyze_Subtype_Declaration;
4925 --------------------------------
4926 -- Analyze_Subtype_Indication --
4927 --------------------------------
4929 procedure Analyze_Subtype_Indication (N : Node_Id) is
4930 T : constant Entity_Id := Subtype_Mark (N);
4931 R : constant Node_Id := Range_Expression (Constraint (N));
4938 Set_Etype (N, Etype (R));
4939 Resolve (R, Entity (T));
4941 Set_Error_Posted (R);
4942 Set_Error_Posted (T);
4944 end Analyze_Subtype_Indication;
4946 --------------------------
4947 -- Analyze_Variant_Part --
4948 --------------------------
4950 procedure Analyze_Variant_Part (N : Node_Id) is
4951 Discr_Name : Node_Id;
4952 Discr_Type : Entity_Id;
4954 procedure Process_Variant (A : Node_Id);
4955 -- Analyze declarations for a single variant
4957 package Analyze_Variant_Choices is
4958 new Generic_Analyze_Choices (Process_Variant);
4959 use Analyze_Variant_Choices;
4961 ---------------------
4962 -- Process_Variant --
4963 ---------------------
4965 procedure Process_Variant (A : Node_Id) is
4966 CL : constant Node_Id := Component_List (A);
4968 if not Null_Present (CL) then
4969 Analyze_Declarations (Component_Items (CL));
4971 if Present (Variant_Part (CL)) then
4972 Analyze (Variant_Part (CL));
4975 end Process_Variant;
4977 -- Start of processing for Analyze_Variant_Part
4980 Discr_Name := Name (N);
4981 Analyze (Discr_Name);
4983 -- If Discr_Name bad, get out (prevent cascaded errors)
4985 if Etype (Discr_Name) = Any_Type then
4989 -- Check invalid discriminant in variant part
4991 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4992 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4995 Discr_Type := Etype (Entity (Discr_Name));
4997 if not Is_Discrete_Type (Discr_Type) then
4999 ("discriminant in a variant part must be of a discrete type",
5004 -- Now analyze the choices, which also analyzes the declarations that
5005 -- are associated with each choice.
5007 Analyze_Choices (Variants (N), Discr_Type);
5009 -- Note: we used to instantiate and call Check_Choices here to check
5010 -- that the choices covered the discriminant, but it's too early to do
5011 -- that because of statically predicated subtypes, whose analysis may
5012 -- be deferred to their freeze point which may be as late as the freeze
5013 -- point of the containing record. So this call is now to be found in
5014 -- Freeze_Record_Declaration.
5016 end Analyze_Variant_Part;
5018 ----------------------------
5019 -- Array_Type_Declaration --
5020 ----------------------------
5022 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5023 Component_Def : constant Node_Id := Component_Definition (Def);
5024 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5025 Element_Type : Entity_Id;
5026 Implicit_Base : Entity_Id;
5028 Related_Id : Entity_Id := Empty;
5030 P : constant Node_Id := Parent (Def);
5034 if Nkind (Def) = N_Constrained_Array_Definition then
5035 Index := First (Discrete_Subtype_Definitions (Def));
5037 Index := First (Subtype_Marks (Def));
5040 -- Find proper names for the implicit types which may be public. In case
5041 -- of anonymous arrays we use the name of the first object of that type
5045 Related_Id := Defining_Identifier (P);
5051 while Present (Index) loop
5054 -- Test for odd case of trying to index a type by the type itself
5056 if Is_Entity_Name (Index) and then Entity (Index) = T then
5057 Error_Msg_N ("type& cannot be indexed by itself", Index);
5058 Set_Entity (Index, Standard_Boolean);
5059 Set_Etype (Index, Standard_Boolean);
5062 -- Check SPARK restriction requiring a subtype mark
5064 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5065 Check_SPARK_Restriction ("subtype mark required", Index);
5068 -- Add a subtype declaration for each index of private array type
5069 -- declaration whose etype is also private. For example:
5072 -- type Index is private;
5074 -- type Table is array (Index) of ...
5077 -- This is currently required by the expander for the internally
5078 -- generated equality subprogram of records with variant parts in
5079 -- which the etype of some component is such private type.
5081 if Ekind (Current_Scope) = E_Package
5082 and then In_Private_Part (Current_Scope)
5083 and then Has_Private_Declaration (Etype (Index))
5086 Loc : constant Source_Ptr := Sloc (Def);
5091 New_E := Make_Temporary (Loc, 'T');
5092 Set_Is_Internal (New_E);
5095 Make_Subtype_Declaration (Loc,
5096 Defining_Identifier => New_E,
5097 Subtype_Indication =>
5098 New_Occurrence_Of (Etype (Index), Loc));
5100 Insert_Before (Parent (Def), Decl);
5102 Set_Etype (Index, New_E);
5104 -- If the index is a range the Entity attribute is not
5105 -- available. Example:
5108 -- type T is private;
5110 -- type T is new Natural;
5111 -- Table : array (T(1) .. T(10)) of Boolean;
5114 if Nkind (Index) /= N_Range then
5115 Set_Entity (Index, New_E);
5120 Make_Index (Index, P, Related_Id, Nb_Index);
5122 -- Check error of subtype with predicate for index type
5124 Bad_Predicated_Subtype_Use
5125 ("subtype& has predicate, not allowed as index subtype",
5126 Index, Etype (Index));
5128 -- Move to next index
5131 Nb_Index := Nb_Index + 1;
5134 -- Process subtype indication if one is present
5136 if Present (Component_Typ) then
5137 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5139 Set_Etype (Component_Typ, Element_Type);
5141 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5142 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
5145 -- Ada 2005 (AI-230): Access Definition case
5147 else pragma Assert (Present (Access_Definition (Component_Def)));
5149 -- Indicate that the anonymous access type is created by the
5150 -- array type declaration.
5152 Element_Type := Access_Definition
5154 N => Access_Definition (Component_Def));
5155 Set_Is_Local_Anonymous_Access (Element_Type);
5157 -- Propagate the parent. This field is needed if we have to generate
5158 -- the master_id associated with an anonymous access to task type
5159 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5161 Set_Parent (Element_Type, Parent (T));
5163 -- Ada 2005 (AI-230): In case of components that are anonymous access
5164 -- types the level of accessibility depends on the enclosing type
5167 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5169 -- Ada 2005 (AI-254)
5172 CD : constant Node_Id :=
5173 Access_To_Subprogram_Definition
5174 (Access_Definition (Component_Def));
5176 if Present (CD) and then Protected_Present (CD) then
5178 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5183 -- Constrained array case
5186 T := Create_Itype (E_Void, P, Related_Id, 'T');
5189 if Nkind (Def) = N_Constrained_Array_Definition then
5191 -- Establish Implicit_Base as unconstrained base type
5193 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5195 Set_Etype (Implicit_Base, Implicit_Base);
5196 Set_Scope (Implicit_Base, Current_Scope);
5197 Set_Has_Delayed_Freeze (Implicit_Base);
5198 Set_Default_SSO (Implicit_Base);
5200 -- The constrained array type is a subtype of the unconstrained one
5202 Set_Ekind (T, E_Array_Subtype);
5203 Init_Size_Align (T);
5204 Set_Etype (T, Implicit_Base);
5205 Set_Scope (T, Current_Scope);
5206 Set_Is_Constrained (T, True);
5207 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
5208 Set_Has_Delayed_Freeze (T);
5210 -- Complete setup of implicit base type
5212 Set_First_Index (Implicit_Base, First_Index (T));
5213 Set_Component_Type (Implicit_Base, Element_Type);
5214 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5215 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5216 Set_Component_Size (Implicit_Base, Uint_0);
5217 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5218 Set_Has_Controlled_Component
5219 (Implicit_Base, Has_Controlled_Component
5221 or else Is_Controlled
5223 Set_Finalize_Storage_Only
5224 (Implicit_Base, Finalize_Storage_Only
5227 -- Unconstrained array case
5230 Set_Ekind (T, E_Array_Type);
5231 Init_Size_Align (T);
5233 Set_Scope (T, Current_Scope);
5234 Set_Component_Size (T, Uint_0);
5235 Set_Is_Constrained (T, False);
5236 Set_First_Index (T, First (Subtype_Marks (Def)));
5237 Set_Has_Delayed_Freeze (T, True);
5238 Set_Has_Task (T, Has_Task (Element_Type));
5239 Set_Has_Protected (T, Has_Protected (Element_Type));
5240 Set_Has_Controlled_Component (T, Has_Controlled_Component
5243 Is_Controlled (Element_Type));
5244 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5246 Set_Default_SSO (T);
5249 -- Common attributes for both cases
5251 Set_Component_Type (Base_Type (T), Element_Type);
5252 Set_Packed_Array_Impl_Type (T, Empty);
5254 if Aliased_Present (Component_Definition (Def)) then
5255 Check_SPARK_Restriction
5256 ("aliased is not allowed", Component_Definition (Def));
5257 Set_Has_Aliased_Components (Etype (T));
5260 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5261 -- array type to ensure that objects of this type are initialized.
5263 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5264 Set_Can_Never_Be_Null (T);
5266 if Null_Exclusion_Present (Component_Definition (Def))
5268 -- No need to check itypes because in their case this check was
5269 -- done at their point of creation
5271 and then not Is_Itype (Element_Type)
5274 ("`NOT NULL` not allowed (null already excluded)",
5275 Subtype_Indication (Component_Definition (Def)));
5279 Priv := Private_Component (Element_Type);
5281 if Present (Priv) then
5283 -- Check for circular definitions
5285 if Priv = Any_Type then
5286 Set_Component_Type (Etype (T), Any_Type);
5288 -- There is a gap in the visibility of operations on the composite
5289 -- type only if the component type is defined in a different scope.
5291 elsif Scope (Priv) = Current_Scope then
5294 elsif Is_Limited_Type (Priv) then
5295 Set_Is_Limited_Composite (Etype (T));
5296 Set_Is_Limited_Composite (T);
5298 Set_Is_Private_Composite (Etype (T));
5299 Set_Is_Private_Composite (T);
5303 -- A syntax error in the declaration itself may lead to an empty index
5304 -- list, in which case do a minimal patch.
5306 if No (First_Index (T)) then
5307 Error_Msg_N ("missing index definition in array type declaration", T);
5310 Indexes : constant List_Id :=
5311 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5313 Set_Discrete_Subtype_Definitions (Def, Indexes);
5314 Set_First_Index (T, First (Indexes));
5319 -- Create a concatenation operator for the new type. Internal array
5320 -- types created for packed entities do not need such, they are
5321 -- compatible with the user-defined type.
5323 if Number_Dimensions (T) = 1
5324 and then not Is_Packed_Array_Impl_Type (T)
5326 New_Concatenation_Op (T);
5329 -- In the case of an unconstrained array the parser has already verified
5330 -- that all the indexes are unconstrained but we still need to make sure
5331 -- that the element type is constrained.
5333 if Is_Indefinite_Subtype (Element_Type) then
5335 ("unconstrained element type in array declaration",
5336 Subtype_Indication (Component_Def));
5338 elsif Is_Abstract_Type (Element_Type) then
5340 ("the type of a component cannot be abstract",
5341 Subtype_Indication (Component_Def));
5344 -- There may be an invariant declared for the component type, but
5345 -- the construction of the component invariant checking procedure
5346 -- takes place during expansion.
5347 end Array_Type_Declaration;
5349 ------------------------------------------------------
5350 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5351 ------------------------------------------------------
5353 function Replace_Anonymous_Access_To_Protected_Subprogram
5354 (N : Node_Id) return Entity_Id
5356 Loc : constant Source_Ptr := Sloc (N);
5358 Curr_Scope : constant Scope_Stack_Entry :=
5359 Scope_Stack.Table (Scope_Stack.Last);
5361 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5364 -- Access definition in declaration
5367 -- Object definition or formal definition with an access definition
5370 -- Declaration of anonymous access to subprogram type
5373 -- Original specification in access to subprogram
5378 Set_Is_Internal (Anon);
5381 when N_Component_Declaration |
5382 N_Unconstrained_Array_Definition |
5383 N_Constrained_Array_Definition =>
5384 Comp := Component_Definition (N);
5385 Acc := Access_Definition (Comp);
5387 when N_Discriminant_Specification =>
5388 Comp := Discriminant_Type (N);
5391 when N_Parameter_Specification =>
5392 Comp := Parameter_Type (N);
5395 when N_Access_Function_Definition =>
5396 Comp := Result_Definition (N);
5399 when N_Object_Declaration =>
5400 Comp := Object_Definition (N);
5403 when N_Function_Specification =>
5404 Comp := Result_Definition (N);
5408 raise Program_Error;
5411 Spec := Access_To_Subprogram_Definition (Acc);
5414 Make_Full_Type_Declaration (Loc,
5415 Defining_Identifier => Anon,
5416 Type_Definition => Copy_Separate_Tree (Spec));
5418 Mark_Rewrite_Insertion (Decl);
5420 -- In ASIS mode, analyze the profile on the original node, because
5421 -- the separate copy does not provide enough links to recover the
5422 -- original tree. Analysis is limited to type annotations, within
5423 -- a temporary scope that serves as an anonymous subprogram to collect
5424 -- otherwise useless temporaries and itypes.
5428 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5431 if Nkind (Spec) = N_Access_Function_Definition then
5432 Set_Ekind (Typ, E_Function);
5434 Set_Ekind (Typ, E_Procedure);
5437 Set_Parent (Typ, N);
5438 Set_Scope (Typ, Current_Scope);
5441 Process_Formals (Parameter_Specifications (Spec), Spec);
5443 if Nkind (Spec) = N_Access_Function_Definition then
5445 Def : constant Node_Id := Result_Definition (Spec);
5448 -- The result might itself be an anonymous access type, so
5451 if Nkind (Def) = N_Access_Definition then
5452 if Present (Access_To_Subprogram_Definition (Def)) then
5455 Replace_Anonymous_Access_To_Protected_Subprogram
5458 Find_Type (Subtype_Mark (Def));
5471 -- Insert the new declaration in the nearest enclosing scope. If the
5472 -- node is a body and N is its return type, the declaration belongs in
5473 -- the enclosing scope.
5477 if Nkind (P) = N_Subprogram_Body
5478 and then Nkind (N) = N_Function_Specification
5483 while Present (P) and then not Has_Declarations (P) loop
5487 pragma Assert (Present (P));
5489 if Nkind (P) = N_Package_Specification then
5490 Prepend (Decl, Visible_Declarations (P));
5492 Prepend (Decl, Declarations (P));
5495 -- Replace the anonymous type with an occurrence of the new declaration.
5496 -- In all cases the rewritten node does not have the null-exclusion
5497 -- attribute because (if present) it was already inherited by the
5498 -- anonymous entity (Anon). Thus, in case of components we do not
5499 -- inherit this attribute.
5501 if Nkind (N) = N_Parameter_Specification then
5502 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5503 Set_Etype (Defining_Identifier (N), Anon);
5504 Set_Null_Exclusion_Present (N, False);
5506 elsif Nkind (N) = N_Object_Declaration then
5507 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5508 Set_Etype (Defining_Identifier (N), Anon);
5510 elsif Nkind (N) = N_Access_Function_Definition then
5511 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5513 elsif Nkind (N) = N_Function_Specification then
5514 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5515 Set_Etype (Defining_Unit_Name (N), Anon);
5519 Make_Component_Definition (Loc,
5520 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5523 Mark_Rewrite_Insertion (Comp);
5525 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5529 -- Temporarily remove the current scope (record or subprogram) from
5530 -- the stack to add the new declarations to the enclosing scope.
5532 Scope_Stack.Decrement_Last;
5534 Set_Is_Itype (Anon);
5535 Scope_Stack.Append (Curr_Scope);
5538 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5539 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5541 end Replace_Anonymous_Access_To_Protected_Subprogram;
5543 -------------------------------
5544 -- Build_Derived_Access_Type --
5545 -------------------------------
5547 procedure Build_Derived_Access_Type
5549 Parent_Type : Entity_Id;
5550 Derived_Type : Entity_Id)
5552 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5554 Desig_Type : Entity_Id;
5556 Discr_Con_Elist : Elist_Id;
5557 Discr_Con_El : Elmt_Id;
5561 -- Set the designated type so it is available in case this is an access
5562 -- to a self-referential type, e.g. a standard list type with a next
5563 -- pointer. Will be reset after subtype is built.
5565 Set_Directly_Designated_Type
5566 (Derived_Type, Designated_Type (Parent_Type));
5568 Subt := Process_Subtype (S, N);
5570 if Nkind (S) /= N_Subtype_Indication
5571 and then Subt /= Base_Type (Subt)
5573 Set_Ekind (Derived_Type, E_Access_Subtype);
5576 if Ekind (Derived_Type) = E_Access_Subtype then
5578 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5579 Ibase : constant Entity_Id :=
5580 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5581 Svg_Chars : constant Name_Id := Chars (Ibase);
5582 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5585 Copy_Node (Pbase, Ibase);
5587 Set_Chars (Ibase, Svg_Chars);
5588 Set_Next_Entity (Ibase, Svg_Next_E);
5589 Set_Sloc (Ibase, Sloc (Derived_Type));
5590 Set_Scope (Ibase, Scope (Derived_Type));
5591 Set_Freeze_Node (Ibase, Empty);
5592 Set_Is_Frozen (Ibase, False);
5593 Set_Comes_From_Source (Ibase, False);
5594 Set_Is_First_Subtype (Ibase, False);
5596 Set_Etype (Ibase, Pbase);
5597 Set_Etype (Derived_Type, Ibase);
5601 Set_Directly_Designated_Type
5602 (Derived_Type, Designated_Type (Subt));
5604 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5605 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5606 Set_Size_Info (Derived_Type, Parent_Type);
5607 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5608 Set_Depends_On_Private (Derived_Type,
5609 Has_Private_Component (Derived_Type));
5610 Conditional_Delay (Derived_Type, Subt);
5612 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5613 -- that it is not redundant.
5615 if Null_Exclusion_Present (Type_Definition (N)) then
5616 Set_Can_Never_Be_Null (Derived_Type);
5618 -- What is with the "AND THEN FALSE" here ???
5620 if Can_Never_Be_Null (Parent_Type)
5624 ("`NOT NULL` not allowed (& already excludes null)",
5628 elsif Can_Never_Be_Null (Parent_Type) then
5629 Set_Can_Never_Be_Null (Derived_Type);
5632 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5633 -- the root type for this information.
5635 -- Apply range checks to discriminants for derived record case
5636 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5638 Desig_Type := Designated_Type (Derived_Type);
5639 if Is_Composite_Type (Desig_Type)
5640 and then (not Is_Array_Type (Desig_Type))
5641 and then Has_Discriminants (Desig_Type)
5642 and then Base_Type (Desig_Type) /= Desig_Type
5644 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5645 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5647 Discr := First_Discriminant (Base_Type (Desig_Type));
5648 while Present (Discr_Con_El) loop
5649 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5650 Next_Elmt (Discr_Con_El);
5651 Next_Discriminant (Discr);
5654 end Build_Derived_Access_Type;
5656 ------------------------------
5657 -- Build_Derived_Array_Type --
5658 ------------------------------
5660 procedure Build_Derived_Array_Type
5662 Parent_Type : Entity_Id;
5663 Derived_Type : Entity_Id)
5665 Loc : constant Source_Ptr := Sloc (N);
5666 Tdef : constant Node_Id := Type_Definition (N);
5667 Indic : constant Node_Id := Subtype_Indication (Tdef);
5668 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5669 Implicit_Base : Entity_Id;
5670 New_Indic : Node_Id;
5672 procedure Make_Implicit_Base;
5673 -- If the parent subtype is constrained, the derived type is a subtype
5674 -- of an implicit base type derived from the parent base.
5676 ------------------------
5677 -- Make_Implicit_Base --
5678 ------------------------
5680 procedure Make_Implicit_Base is
5683 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5685 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5686 Set_Etype (Implicit_Base, Parent_Base);
5688 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5689 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5691 Set_Has_Delayed_Freeze (Implicit_Base, True);
5692 end Make_Implicit_Base;
5694 -- Start of processing for Build_Derived_Array_Type
5697 if not Is_Constrained (Parent_Type) then
5698 if Nkind (Indic) /= N_Subtype_Indication then
5699 Set_Ekind (Derived_Type, E_Array_Type);
5701 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5702 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5704 Set_Has_Delayed_Freeze (Derived_Type, True);
5708 Set_Etype (Derived_Type, Implicit_Base);
5711 Make_Subtype_Declaration (Loc,
5712 Defining_Identifier => Derived_Type,
5713 Subtype_Indication =>
5714 Make_Subtype_Indication (Loc,
5715 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5716 Constraint => Constraint (Indic)));
5718 Rewrite (N, New_Indic);
5723 if Nkind (Indic) /= N_Subtype_Indication then
5726 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5727 Set_Etype (Derived_Type, Implicit_Base);
5728 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5731 Error_Msg_N ("illegal constraint on constrained type", Indic);
5735 -- If parent type is not a derived type itself, and is declared in
5736 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5737 -- the new type's concatenation operator since Derive_Subprograms
5738 -- will not inherit the parent's operator. If the parent type is
5739 -- unconstrained, the operator is of the unconstrained base type.
5741 if Number_Dimensions (Parent_Type) = 1
5742 and then not Is_Limited_Type (Parent_Type)
5743 and then not Is_Derived_Type (Parent_Type)
5744 and then not Is_Package_Or_Generic_Package
5745 (Scope (Base_Type (Parent_Type)))
5747 if not Is_Constrained (Parent_Type)
5748 and then Is_Constrained (Derived_Type)
5750 New_Concatenation_Op (Implicit_Base);
5752 New_Concatenation_Op (Derived_Type);
5755 end Build_Derived_Array_Type;
5757 -----------------------------------
5758 -- Build_Derived_Concurrent_Type --
5759 -----------------------------------
5761 procedure Build_Derived_Concurrent_Type
5763 Parent_Type : Entity_Id;
5764 Derived_Type : Entity_Id)
5766 Loc : constant Source_Ptr := Sloc (N);
5768 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5769 Corr_Decl : Node_Id;
5770 Corr_Decl_Needed : Boolean;
5771 -- If the derived type has fewer discriminants than its parent, the
5772 -- corresponding record is also a derived type, in order to account for
5773 -- the bound discriminants. We create a full type declaration for it in
5776 Constraint_Present : constant Boolean :=
5777 Nkind (Subtype_Indication (Type_Definition (N))) =
5778 N_Subtype_Indication;
5780 D_Constraint : Node_Id;
5781 New_Constraint : Elist_Id;
5782 Old_Disc : Entity_Id;
5783 New_Disc : Entity_Id;
5787 Set_Stored_Constraint (Derived_Type, No_Elist);
5788 Corr_Decl_Needed := False;
5791 if Present (Discriminant_Specifications (N))
5792 and then Constraint_Present
5794 Old_Disc := First_Discriminant (Parent_Type);
5795 New_Disc := First (Discriminant_Specifications (N));
5796 while Present (New_Disc) and then Present (Old_Disc) loop
5797 Next_Discriminant (Old_Disc);
5802 if Present (Old_Disc) and then Expander_Active then
5804 -- The new type has fewer discriminants, so we need to create a new
5805 -- corresponding record, which is derived from the corresponding
5806 -- record of the parent, and has a stored constraint that captures
5807 -- the values of the discriminant constraints. The corresponding
5808 -- record is needed only if expander is active and code generation is
5811 -- The type declaration for the derived corresponding record has the
5812 -- same discriminant part and constraints as the current declaration.
5813 -- Copy the unanalyzed tree to build declaration.
5815 Corr_Decl_Needed := True;
5816 New_N := Copy_Separate_Tree (N);
5819 Make_Full_Type_Declaration (Loc,
5820 Defining_Identifier => Corr_Record,
5821 Discriminant_Specifications =>
5822 Discriminant_Specifications (New_N),
5824 Make_Derived_Type_Definition (Loc,
5825 Subtype_Indication =>
5826 Make_Subtype_Indication (Loc,
5829 (Corresponding_Record_Type (Parent_Type), Loc),
5832 (Subtype_Indication (Type_Definition (New_N))))));
5835 -- Copy Storage_Size and Relative_Deadline variables if task case
5837 if Is_Task_Type (Parent_Type) then
5838 Set_Storage_Size_Variable (Derived_Type,
5839 Storage_Size_Variable (Parent_Type));
5840 Set_Relative_Deadline_Variable (Derived_Type,
5841 Relative_Deadline_Variable (Parent_Type));
5844 if Present (Discriminant_Specifications (N)) then
5845 Push_Scope (Derived_Type);
5846 Check_Or_Process_Discriminants (N, Derived_Type);
5848 if Constraint_Present then
5850 Expand_To_Stored_Constraint
5852 Build_Discriminant_Constraints
5854 Subtype_Indication (Type_Definition (N)), True));
5859 elsif Constraint_Present then
5861 -- Build constrained subtype, copying the constraint, and derive
5862 -- from it to create a derived constrained type.
5865 Loc : constant Source_Ptr := Sloc (N);
5866 Anon : constant Entity_Id :=
5867 Make_Defining_Identifier (Loc,
5868 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5873 Make_Subtype_Declaration (Loc,
5874 Defining_Identifier => Anon,
5875 Subtype_Indication =>
5876 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
5877 Insert_Before (N, Decl);
5880 Rewrite (Subtype_Indication (Type_Definition (N)),
5881 New_Occurrence_Of (Anon, Loc));
5882 Set_Analyzed (Derived_Type, False);
5888 -- By default, operations and private data are inherited from parent.
5889 -- However, in the presence of bound discriminants, a new corresponding
5890 -- record will be created, see below.
5892 Set_Has_Discriminants
5893 (Derived_Type, Has_Discriminants (Parent_Type));
5894 Set_Corresponding_Record_Type
5895 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5897 -- Is_Constrained is set according the parent subtype, but is set to
5898 -- False if the derived type is declared with new discriminants.
5902 (Is_Constrained (Parent_Type) or else Constraint_Present)
5903 and then not Present (Discriminant_Specifications (N)));
5905 if Constraint_Present then
5906 if not Has_Discriminants (Parent_Type) then
5907 Error_Msg_N ("untagged parent must have discriminants", N);
5909 elsif Present (Discriminant_Specifications (N)) then
5911 -- Verify that new discriminants are used to constrain old ones
5916 (Constraint (Subtype_Indication (Type_Definition (N)))));
5918 Old_Disc := First_Discriminant (Parent_Type);
5920 while Present (D_Constraint) loop
5921 if Nkind (D_Constraint) /= N_Discriminant_Association then
5923 -- Positional constraint. If it is a reference to a new
5924 -- discriminant, it constrains the corresponding old one.
5926 if Nkind (D_Constraint) = N_Identifier then
5927 New_Disc := First_Discriminant (Derived_Type);
5928 while Present (New_Disc) loop
5929 exit when Chars (New_Disc) = Chars (D_Constraint);
5930 Next_Discriminant (New_Disc);
5933 if Present (New_Disc) then
5934 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5938 Next_Discriminant (Old_Disc);
5940 -- if this is a named constraint, search by name for the old
5941 -- discriminants constrained by the new one.
5943 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5945 -- Find new discriminant with that name
5947 New_Disc := First_Discriminant (Derived_Type);
5948 while Present (New_Disc) loop
5950 Chars (New_Disc) = Chars (Expression (D_Constraint));
5951 Next_Discriminant (New_Disc);
5954 if Present (New_Disc) then
5956 -- Verify that new discriminant renames some discriminant
5957 -- of the parent type, and associate the new discriminant
5958 -- with one or more old ones that it renames.
5964 Selector := First (Selector_Names (D_Constraint));
5965 while Present (Selector) loop
5966 Old_Disc := First_Discriminant (Parent_Type);
5967 while Present (Old_Disc) loop
5968 exit when Chars (Old_Disc) = Chars (Selector);
5969 Next_Discriminant (Old_Disc);
5972 if Present (Old_Disc) then
5973 Set_Corresponding_Discriminant
5974 (New_Disc, Old_Disc);
5983 Next (D_Constraint);
5986 New_Disc := First_Discriminant (Derived_Type);
5987 while Present (New_Disc) loop
5988 if No (Corresponding_Discriminant (New_Disc)) then
5990 ("new discriminant& must constrain old one", N, New_Disc);
5993 Subtypes_Statically_Compatible
5995 Etype (Corresponding_Discriminant (New_Disc)))
5998 ("& not statically compatible with parent discriminant",
6002 Next_Discriminant (New_Disc);
6006 elsif Present (Discriminant_Specifications (N)) then
6008 ("missing discriminant constraint in untagged derivation", N);
6011 -- The entity chain of the derived type includes the new discriminants
6012 -- but shares operations with the parent.
6014 if Present (Discriminant_Specifications (N)) then
6015 Old_Disc := First_Discriminant (Parent_Type);
6016 while Present (Old_Disc) loop
6017 if No (Next_Entity (Old_Disc))
6018 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6021 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6025 Next_Discriminant (Old_Disc);
6029 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6030 if Has_Discriminants (Parent_Type) then
6031 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6032 Set_Discriminant_Constraint (
6033 Derived_Type, Discriminant_Constraint (Parent_Type));
6037 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6039 Set_Has_Completion (Derived_Type);
6041 if Corr_Decl_Needed then
6042 Set_Stored_Constraint (Derived_Type, New_Constraint);
6043 Insert_After (N, Corr_Decl);
6044 Analyze (Corr_Decl);
6045 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6047 end Build_Derived_Concurrent_Type;
6049 ------------------------------------
6050 -- Build_Derived_Enumeration_Type --
6051 ------------------------------------
6053 procedure Build_Derived_Enumeration_Type
6055 Parent_Type : Entity_Id;
6056 Derived_Type : Entity_Id)
6058 Loc : constant Source_Ptr := Sloc (N);
6059 Def : constant Node_Id := Type_Definition (N);
6060 Indic : constant Node_Id := Subtype_Indication (Def);
6061 Implicit_Base : Entity_Id;
6062 Literal : Entity_Id;
6063 New_Lit : Entity_Id;
6064 Literals_List : List_Id;
6065 Type_Decl : Node_Id;
6067 Rang_Expr : Node_Id;
6070 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6071 -- not have explicit literals lists we need to process types derived
6072 -- from them specially. This is handled by Derived_Standard_Character.
6073 -- If the parent type is a generic type, there are no literals either,
6074 -- and we construct the same skeletal representation as for the generic
6077 if Is_Standard_Character_Type (Parent_Type) then
6078 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6080 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6086 if Nkind (Indic) /= N_Subtype_Indication then
6088 Make_Attribute_Reference (Loc,
6089 Attribute_Name => Name_First,
6090 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6091 Set_Etype (Lo, Derived_Type);
6094 Make_Attribute_Reference (Loc,
6095 Attribute_Name => Name_Last,
6096 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6097 Set_Etype (Hi, Derived_Type);
6099 Set_Scalar_Range (Derived_Type,
6105 -- Analyze subtype indication and verify compatibility
6106 -- with parent type.
6108 if Base_Type (Process_Subtype (Indic, N)) /=
6109 Base_Type (Parent_Type)
6112 ("illegal constraint for formal discrete type", N);
6118 -- If a constraint is present, analyze the bounds to catch
6119 -- premature usage of the derived literals.
6121 if Nkind (Indic) = N_Subtype_Indication
6122 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6124 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6125 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6128 -- Introduce an implicit base type for the derived type even if there
6129 -- is no constraint attached to it, since this seems closer to the
6130 -- Ada semantics. Build a full type declaration tree for the derived
6131 -- type using the implicit base type as the defining identifier. The
6132 -- build a subtype declaration tree which applies the constraint (if
6133 -- any) have it replace the derived type declaration.
6135 Literal := First_Literal (Parent_Type);
6136 Literals_List := New_List;
6137 while Present (Literal)
6138 and then Ekind (Literal) = E_Enumeration_Literal
6140 -- Literals of the derived type have the same representation as
6141 -- those of the parent type, but this representation can be
6142 -- overridden by an explicit representation clause. Indicate
6143 -- that there is no explicit representation given yet. These
6144 -- derived literals are implicit operations of the new type,
6145 -- and can be overridden by explicit ones.
6147 if Nkind (Literal) = N_Defining_Character_Literal then
6149 Make_Defining_Character_Literal (Loc, Chars (Literal));
6151 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6154 Set_Ekind (New_Lit, E_Enumeration_Literal);
6155 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6156 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6157 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6158 Set_Alias (New_Lit, Literal);
6159 Set_Is_Known_Valid (New_Lit, True);
6161 Append (New_Lit, Literals_List);
6162 Next_Literal (Literal);
6166 Make_Defining_Identifier (Sloc (Derived_Type),
6167 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6169 -- Indicate the proper nature of the derived type. This must be done
6170 -- before analysis of the literals, to recognize cases when a literal
6171 -- may be hidden by a previous explicit function definition (cf.
6174 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6175 Set_Etype (Derived_Type, Implicit_Base);
6178 Make_Full_Type_Declaration (Loc,
6179 Defining_Identifier => Implicit_Base,
6180 Discriminant_Specifications => No_List,
6182 Make_Enumeration_Type_Definition (Loc, Literals_List));
6184 Mark_Rewrite_Insertion (Type_Decl);
6185 Insert_Before (N, Type_Decl);
6186 Analyze (Type_Decl);
6188 -- After the implicit base is analyzed its Etype needs to be changed
6189 -- to reflect the fact that it is derived from the parent type which
6190 -- was ignored during analysis. We also set the size at this point.
6192 Set_Etype (Implicit_Base, Parent_Type);
6194 Set_Size_Info (Implicit_Base, Parent_Type);
6195 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6196 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6198 -- Copy other flags from parent type
6200 Set_Has_Non_Standard_Rep
6201 (Implicit_Base, Has_Non_Standard_Rep
6203 Set_Has_Pragma_Ordered
6204 (Implicit_Base, Has_Pragma_Ordered
6206 Set_Has_Delayed_Freeze (Implicit_Base);
6208 -- Process the subtype indication including a validation check on the
6209 -- constraint, if any. If a constraint is given, its bounds must be
6210 -- implicitly converted to the new type.
6212 if Nkind (Indic) = N_Subtype_Indication then
6214 R : constant Node_Id :=
6215 Range_Expression (Constraint (Indic));
6218 if Nkind (R) = N_Range then
6219 Hi := Build_Scalar_Bound
6220 (High_Bound (R), Parent_Type, Implicit_Base);
6221 Lo := Build_Scalar_Bound
6222 (Low_Bound (R), Parent_Type, Implicit_Base);
6225 -- Constraint is a Range attribute. Replace with explicit
6226 -- mention of the bounds of the prefix, which must be a
6229 Analyze (Prefix (R));
6231 Convert_To (Implicit_Base,
6232 Make_Attribute_Reference (Loc,
6233 Attribute_Name => Name_Last,
6235 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6238 Convert_To (Implicit_Base,
6239 Make_Attribute_Reference (Loc,
6240 Attribute_Name => Name_First,
6242 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6249 (Type_High_Bound (Parent_Type),
6250 Parent_Type, Implicit_Base);
6253 (Type_Low_Bound (Parent_Type),
6254 Parent_Type, Implicit_Base);
6262 -- If we constructed a default range for the case where no range
6263 -- was given, then the expressions in the range must not freeze
6264 -- since they do not correspond to expressions in the source.
6266 if Nkind (Indic) /= N_Subtype_Indication then
6267 Set_Must_Not_Freeze (Lo);
6268 Set_Must_Not_Freeze (Hi);
6269 Set_Must_Not_Freeze (Rang_Expr);
6273 Make_Subtype_Declaration (Loc,
6274 Defining_Identifier => Derived_Type,
6275 Subtype_Indication =>
6276 Make_Subtype_Indication (Loc,
6277 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6279 Make_Range_Constraint (Loc,
6280 Range_Expression => Rang_Expr))));
6284 -- Apply a range check. Since this range expression doesn't have an
6285 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6288 if Nkind (Indic) = N_Subtype_Indication then
6289 Apply_Range_Check (Range_Expression (Constraint (Indic)),
6291 Source_Typ => Entity (Subtype_Mark (Indic)));
6294 end Build_Derived_Enumeration_Type;
6296 --------------------------------
6297 -- Build_Derived_Numeric_Type --
6298 --------------------------------
6300 procedure Build_Derived_Numeric_Type
6302 Parent_Type : Entity_Id;
6303 Derived_Type : Entity_Id)
6305 Loc : constant Source_Ptr := Sloc (N);
6306 Tdef : constant Node_Id := Type_Definition (N);
6307 Indic : constant Node_Id := Subtype_Indication (Tdef);
6308 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6309 No_Constraint : constant Boolean := Nkind (Indic) /=
6310 N_Subtype_Indication;
6311 Implicit_Base : Entity_Id;
6317 -- Process the subtype indication including a validation check on
6318 -- the constraint if any.
6320 Discard_Node (Process_Subtype (Indic, N));
6322 -- Introduce an implicit base type for the derived type even if there
6323 -- is no constraint attached to it, since this seems closer to the Ada
6327 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6329 Set_Etype (Implicit_Base, Parent_Base);
6330 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6331 Set_Size_Info (Implicit_Base, Parent_Base);
6332 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6333 Set_Parent (Implicit_Base, Parent (Derived_Type));
6334 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6336 -- Set RM Size for discrete type or decimal fixed-point type
6337 -- Ordinary fixed-point is excluded, why???
6339 if Is_Discrete_Type (Parent_Base)
6340 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6342 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6345 Set_Has_Delayed_Freeze (Implicit_Base);
6347 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6348 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6350 Set_Scalar_Range (Implicit_Base,
6355 if Has_Infinities (Parent_Base) then
6356 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6359 -- The Derived_Type, which is the entity of the declaration, is a
6360 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6361 -- absence of an explicit constraint.
6363 Set_Etype (Derived_Type, Implicit_Base);
6365 -- If we did not have a constraint, then the Ekind is set from the
6366 -- parent type (otherwise Process_Subtype has set the bounds)
6368 if No_Constraint then
6369 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6372 -- If we did not have a range constraint, then set the range from the
6373 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6376 or else not Has_Range_Constraint (Indic)
6378 Set_Scalar_Range (Derived_Type,
6380 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6381 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6382 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6384 if Has_Infinities (Parent_Type) then
6385 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6388 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6391 Set_Is_Descendent_Of_Address (Derived_Type,
6392 Is_Descendent_Of_Address (Parent_Type));
6393 Set_Is_Descendent_Of_Address (Implicit_Base,
6394 Is_Descendent_Of_Address (Parent_Type));
6396 -- Set remaining type-specific fields, depending on numeric type
6398 if Is_Modular_Integer_Type (Parent_Type) then
6399 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6401 Set_Non_Binary_Modulus
6402 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6405 (Implicit_Base, Is_Known_Valid (Parent_Base));
6407 elsif Is_Floating_Point_Type (Parent_Type) then
6409 -- Digits of base type is always copied from the digits value of
6410 -- the parent base type, but the digits of the derived type will
6411 -- already have been set if there was a constraint present.
6413 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6414 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6416 if No_Constraint then
6417 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6420 elsif Is_Fixed_Point_Type (Parent_Type) then
6422 -- Small of base type and derived type are always copied from the
6423 -- parent base type, since smalls never change. The delta of the
6424 -- base type is also copied from the parent base type. However the
6425 -- delta of the derived type will have been set already if a
6426 -- constraint was present.
6428 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6429 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6430 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6432 if No_Constraint then
6433 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6436 -- The scale and machine radix in the decimal case are always
6437 -- copied from the parent base type.
6439 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6440 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6441 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6443 Set_Machine_Radix_10
6444 (Derived_Type, Machine_Radix_10 (Parent_Base));
6445 Set_Machine_Radix_10
6446 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6448 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6450 if No_Constraint then
6451 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6454 -- the analysis of the subtype_indication sets the
6455 -- digits value of the derived type.
6462 if Is_Integer_Type (Parent_Type) then
6463 Set_Has_Shift_Operator
6464 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6467 -- The type of the bounds is that of the parent type, and they
6468 -- must be converted to the derived type.
6470 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6472 -- The implicit_base should be frozen when the derived type is frozen,
6473 -- but note that it is used in the conversions of the bounds. For fixed
6474 -- types we delay the determination of the bounds until the proper
6475 -- freezing point. For other numeric types this is rejected by GCC, for
6476 -- reasons that are currently unclear (???), so we choose to freeze the
6477 -- implicit base now. In the case of integers and floating point types
6478 -- this is harmless because subsequent representation clauses cannot
6479 -- affect anything, but it is still baffling that we cannot use the
6480 -- same mechanism for all derived numeric types.
6482 -- There is a further complication: actually some representation
6483 -- clauses can affect the implicit base type. For example, attribute
6484 -- definition clauses for stream-oriented attributes need to set the
6485 -- corresponding TSS entries on the base type, and this normally
6486 -- cannot be done after the base type is frozen, so the circuitry in
6487 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6488 -- and not use Set_TSS in this case.
6490 -- There are also consequences for the case of delayed representation
6491 -- aspects for some cases. For example, a Size aspect is delayed and
6492 -- should not be evaluated to the freeze point. This early freezing
6493 -- means that the size attribute evaluation happens too early???
6495 if Is_Fixed_Point_Type (Parent_Type) then
6496 Conditional_Delay (Implicit_Base, Parent_Type);
6498 Freeze_Before (N, Implicit_Base);
6500 end Build_Derived_Numeric_Type;
6502 --------------------------------
6503 -- Build_Derived_Private_Type --
6504 --------------------------------
6506 procedure Build_Derived_Private_Type
6508 Parent_Type : Entity_Id;
6509 Derived_Type : Entity_Id;
6510 Is_Completion : Boolean;
6511 Derive_Subps : Boolean := True)
6513 Loc : constant Source_Ptr := Sloc (N);
6514 Der_Base : Entity_Id;
6516 Full_Decl : Node_Id := Empty;
6517 Full_Der : Entity_Id;
6519 Last_Discr : Entity_Id;
6520 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6521 Swapped : Boolean := False;
6523 procedure Copy_And_Build;
6524 -- Copy derived type declaration, replace parent with its full view,
6525 -- and analyze new declaration.
6527 --------------------
6528 -- Copy_And_Build --
6529 --------------------
6531 procedure Copy_And_Build is
6535 if Ekind (Parent_Type) in Record_Kind
6537 (Ekind (Parent_Type) in Enumeration_Kind
6538 and then not Is_Standard_Character_Type (Parent_Type)
6539 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6541 Full_N := New_Copy_Tree (N);
6542 Insert_After (N, Full_N);
6543 Build_Derived_Type (
6544 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6547 Build_Derived_Type (
6548 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6552 -- Start of processing for Build_Derived_Private_Type
6555 if Is_Tagged_Type (Parent_Type) then
6556 Full_P := Full_View (Parent_Type);
6558 -- A type extension of a type with unknown discriminants is an
6559 -- indefinite type that the back-end cannot handle directly.
6560 -- We treat it as a private type, and build a completion that is
6561 -- derived from the full view of the parent, and hopefully has
6562 -- known discriminants.
6564 -- If the full view of the parent type has an underlying record view,
6565 -- use it to generate the underlying record view of this derived type
6566 -- (required for chains of derivations with unknown discriminants).
6568 -- Minor optimization: we avoid the generation of useless underlying
6569 -- record view entities if the private type declaration has unknown
6570 -- discriminants but its corresponding full view has no
6573 if Has_Unknown_Discriminants (Parent_Type)
6574 and then Present (Full_P)
6575 and then (Has_Discriminants (Full_P)
6576 or else Present (Underlying_Record_View (Full_P)))
6577 and then not In_Open_Scopes (Par_Scope)
6578 and then Expander_Active
6581 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6582 New_Ext : constant Node_Id :=
6584 (Record_Extension_Part (Type_Definition (N)));
6588 Build_Derived_Record_Type
6589 (N, Parent_Type, Derived_Type, Derive_Subps);
6591 -- Build anonymous completion, as a derivation from the full
6592 -- view of the parent. This is not a completion in the usual
6593 -- sense, because the current type is not private.
6596 Make_Full_Type_Declaration (Loc,
6597 Defining_Identifier => Full_Der,
6599 Make_Derived_Type_Definition (Loc,
6600 Subtype_Indication =>
6602 (Subtype_Indication (Type_Definition (N))),
6603 Record_Extension_Part => New_Ext));
6605 -- If the parent type has an underlying record view, use it
6606 -- here to build the new underlying record view.
6608 if Present (Underlying_Record_View (Full_P)) then
6610 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6612 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6613 Underlying_Record_View (Full_P));
6616 Install_Private_Declarations (Par_Scope);
6617 Install_Visible_Declarations (Par_Scope);
6618 Insert_Before (N, Decl);
6620 -- Mark entity as an underlying record view before analysis,
6621 -- to avoid generating the list of its primitive operations
6622 -- (which is not really required for this entity) and thus
6623 -- prevent spurious errors associated with missing overriding
6624 -- of abstract primitives (overridden only for Derived_Type).
6626 Set_Ekind (Full_Der, E_Record_Type);
6627 Set_Is_Underlying_Record_View (Full_Der);
6628 Set_Default_SSO (Full_Der);
6632 pragma Assert (Has_Discriminants (Full_Der)
6633 and then not Has_Unknown_Discriminants (Full_Der));
6635 Uninstall_Declarations (Par_Scope);
6637 -- Freeze the underlying record view, to prevent generation of
6638 -- useless dispatching information, which is simply shared with
6639 -- the real derived type.
6641 Set_Is_Frozen (Full_Der);
6643 -- Set up links between real entity and underlying record view
6645 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6646 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6649 -- If discriminants are known, build derived record
6652 Build_Derived_Record_Type
6653 (N, Parent_Type, Derived_Type, Derive_Subps);
6658 elsif Has_Discriminants (Parent_Type) then
6659 if Present (Full_View (Parent_Type)) then
6660 if not Is_Completion then
6662 -- Copy declaration for subsequent analysis, to provide a
6663 -- completion for what is a private declaration. Indicate that
6664 -- the full type is internally generated.
6666 Full_Decl := New_Copy_Tree (N);
6667 Full_Der := New_Copy (Derived_Type);
6668 Set_Comes_From_Source (Full_Decl, False);
6669 Set_Comes_From_Source (Full_Der, False);
6670 Set_Parent (Full_Der, Full_Decl);
6672 Insert_After (N, Full_Decl);
6675 -- If this is a completion, the full view being built is itself
6676 -- private. We build a subtype of the parent with the same
6677 -- constraints as this full view, to convey to the back end the
6678 -- constrained components and the size of this subtype. If the
6679 -- parent is constrained, its full view can serve as the
6680 -- underlying full view of the derived type.
6682 if No (Discriminant_Specifications (N)) then
6683 if Nkind (Subtype_Indication (Type_Definition (N))) =
6684 N_Subtype_Indication
6686 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6688 elsif Is_Constrained (Full_View (Parent_Type)) then
6689 Set_Underlying_Full_View
6690 (Derived_Type, Full_View (Parent_Type));
6694 -- If there are new discriminants, the parent subtype is
6695 -- constrained by them, but it is not clear how to build
6696 -- the Underlying_Full_View in this case???
6703 -- Build partial view of derived type from partial view of parent
6705 Build_Derived_Record_Type
6706 (N, Parent_Type, Derived_Type, Derive_Subps);
6708 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6709 if not In_Open_Scopes (Par_Scope)
6710 or else not In_Same_Source_Unit (N, Parent_Type)
6712 -- Swap partial and full views temporarily
6714 Install_Private_Declarations (Par_Scope);
6715 Install_Visible_Declarations (Par_Scope);
6719 -- Build full view of derived type from full view of parent which
6720 -- is now installed. Subprograms have been derived on the partial
6721 -- view, the completion does not derive them anew.
6723 if not Is_Tagged_Type (Parent_Type) then
6725 -- If the parent is itself derived from another private type,
6726 -- installing the private declarations has not affected its
6727 -- privacy status, so use its own full view explicitly.
6729 if Is_Private_Type (Parent_Type) then
6730 Build_Derived_Record_Type
6731 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6733 Build_Derived_Record_Type
6734 (Full_Decl, Parent_Type, Full_Der, False);
6738 -- If full view of parent is tagged, the completion inherits
6739 -- the proper primitive operations.
6741 Set_Defining_Identifier (Full_Decl, Full_Der);
6742 Build_Derived_Record_Type
6743 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6746 -- The full declaration has been introduced into the tree and
6747 -- processed in the step above. It should not be analyzed again
6748 -- (when encountered later in the current list of declarations)
6749 -- to prevent spurious name conflicts. The full entity remains
6752 Set_Analyzed (Full_Decl);
6755 Uninstall_Declarations (Par_Scope);
6757 if In_Open_Scopes (Par_Scope) then
6758 Install_Visible_Declarations (Par_Scope);
6762 Der_Base := Base_Type (Derived_Type);
6763 Set_Full_View (Derived_Type, Full_Der);
6764 Set_Full_View (Der_Base, Base_Type (Full_Der));
6766 -- Copy the discriminant list from full view to the partial views
6767 -- (base type and its subtype). Gigi requires that the partial and
6768 -- full views have the same discriminants.
6770 -- Note that since the partial view is pointing to discriminants
6771 -- in the full view, their scope will be that of the full view.
6772 -- This might cause some front end problems and need adjustment???
6774 Discr := First_Discriminant (Base_Type (Full_Der));
6775 Set_First_Entity (Der_Base, Discr);
6778 Last_Discr := Discr;
6779 Next_Discriminant (Discr);
6780 exit when No (Discr);
6783 Set_Last_Entity (Der_Base, Last_Discr);
6785 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6786 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6787 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6790 -- If this is a completion, the derived type stays private and
6791 -- there is no need to create a further full view, except in the
6792 -- unusual case when the derivation is nested within a child unit,
6798 elsif Present (Full_View (Parent_Type))
6799 and then Has_Discriminants (Full_View (Parent_Type))
6801 if Has_Unknown_Discriminants (Parent_Type)
6802 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6803 N_Subtype_Indication
6806 ("cannot constrain type with unknown discriminants",
6807 Subtype_Indication (Type_Definition (N)));
6811 -- If full view of parent is a record type, build full view as a
6812 -- derivation from the parent's full view. Partial view remains
6813 -- private. For code generation and linking, the full view must have
6814 -- the same public status as the partial one. This full view is only
6815 -- needed if the parent type is in an enclosing scope, so that the
6816 -- full view may actually become visible, e.g. in a child unit. This
6817 -- is both more efficient, and avoids order of freezing problems with
6818 -- the added entities.
6820 if not Is_Private_Type (Full_View (Parent_Type))
6821 and then (In_Open_Scopes (Scope (Parent_Type)))
6824 Make_Defining_Identifier (Sloc (Derived_Type),
6825 Chars => Chars (Derived_Type));
6827 Set_Is_Itype (Full_Der);
6828 Set_Has_Private_Declaration (Full_Der);
6829 Set_Has_Private_Declaration (Derived_Type);
6830 Set_Associated_Node_For_Itype (Full_Der, N);
6831 Set_Parent (Full_Der, Parent (Derived_Type));
6832 Set_Full_View (Derived_Type, Full_Der);
6833 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6834 Full_P := Full_View (Parent_Type);
6835 Exchange_Declarations (Parent_Type);
6837 Exchange_Declarations (Full_P);
6840 Build_Derived_Record_Type
6841 (N, Full_View (Parent_Type), Derived_Type,
6842 Derive_Subps => False);
6844 -- Except in the context of the full view of the parent, there
6845 -- are no non-extension aggregates for the derived type.
6847 Set_Has_Private_Ancestor (Derived_Type);
6850 -- In any case, the primitive operations are inherited from the
6851 -- parent type, not from the internal full view.
6853 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6855 if Derive_Subps then
6856 Derive_Subprograms (Parent_Type, Derived_Type);
6860 -- Untagged type, No discriminants on either view
6862 if Nkind (Subtype_Indication (Type_Definition (N))) =
6863 N_Subtype_Indication
6866 ("illegal constraint on type without discriminants", N);
6869 if Present (Discriminant_Specifications (N))
6870 and then Present (Full_View (Parent_Type))
6871 and then not Is_Tagged_Type (Full_View (Parent_Type))
6873 Error_Msg_N ("cannot add discriminants to untagged type", N);
6876 Set_Stored_Constraint (Derived_Type, No_Elist);
6877 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6878 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6879 Set_Has_Controlled_Component
6880 (Derived_Type, Has_Controlled_Component
6883 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6885 if not Is_Controlled (Parent_Type) then
6886 Set_Finalize_Storage_Only
6887 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6890 -- Construct the implicit full view by deriving from full view of the
6891 -- parent type. In order to get proper visibility, we install the
6892 -- parent scope and its declarations.
6894 -- ??? If the parent is untagged private and its completion is
6895 -- tagged, this mechanism will not work because we cannot derive from
6896 -- the tagged full view unless we have an extension.
6898 if Present (Full_View (Parent_Type))
6899 and then not Is_Tagged_Type (Full_View (Parent_Type))
6900 and then not Is_Completion
6903 Make_Defining_Identifier
6904 (Sloc (Derived_Type), Chars (Derived_Type));
6905 Set_Is_Itype (Full_Der);
6906 Set_Has_Private_Declaration (Full_Der);
6907 Set_Has_Private_Declaration (Derived_Type);
6908 Set_Associated_Node_For_Itype (Full_Der, N);
6909 Set_Parent (Full_Der, Parent (Derived_Type));
6910 Set_Full_View (Derived_Type, Full_Der);
6912 if not In_Open_Scopes (Par_Scope) then
6913 Install_Private_Declarations (Par_Scope);
6914 Install_Visible_Declarations (Par_Scope);
6916 Uninstall_Declarations (Par_Scope);
6918 -- If parent scope is open and in another unit, and parent has a
6919 -- completion, then the derivation is taking place in the visible
6920 -- part of a child unit. In that case retrieve the full view of
6921 -- the parent momentarily.
6923 elsif not In_Same_Source_Unit (N, Parent_Type) then
6924 Full_P := Full_View (Parent_Type);
6925 Exchange_Declarations (Parent_Type);
6927 Exchange_Declarations (Full_P);
6929 -- Otherwise it is a local derivation
6935 Set_Scope (Full_Der, Current_Scope);
6936 Set_Is_First_Subtype (Full_Der,
6937 Is_First_Subtype (Derived_Type));
6938 Set_Has_Size_Clause (Full_Der, False);
6939 Set_Has_Alignment_Clause (Full_Der, False);
6940 Set_Next_Entity (Full_Der, Empty);
6941 Set_Has_Delayed_Freeze (Full_Der);
6942 Set_Is_Frozen (Full_Der, False);
6943 Set_Freeze_Node (Full_Der, Empty);
6944 Set_Depends_On_Private (Full_Der,
6945 Has_Private_Component (Full_Der));
6946 Set_Public_Status (Full_Der);
6950 Set_Has_Unknown_Discriminants (Derived_Type,
6951 Has_Unknown_Discriminants (Parent_Type));
6953 if Is_Private_Type (Derived_Type) then
6954 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6957 if Is_Private_Type (Parent_Type)
6958 and then Base_Type (Parent_Type) = Parent_Type
6959 and then In_Open_Scopes (Scope (Parent_Type))
6961 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6963 -- Check for unusual case where a type completed by a private
6964 -- derivation occurs within a package nested in a child unit, and
6965 -- the parent is declared in an ancestor.
6967 if Is_Child_Unit (Scope (Current_Scope))
6968 and then Is_Completion
6969 and then In_Private_Part (Current_Scope)
6970 and then Scope (Parent_Type) /= Current_Scope
6972 -- Note that if the parent has a completion in the private part,
6973 -- (which is itself a derivation from some other private type)
6974 -- it is that completion that is visible, there is no full view
6975 -- available, and no special processing is needed.
6977 and then Present (Full_View (Parent_Type))
6979 -- In this case, the full view of the parent type will become
6980 -- visible in the body of the enclosing child, and only then will
6981 -- the current type be possibly non-private. We build an
6982 -- underlying full view that will be installed when the enclosing
6983 -- child body is compiled.
6986 Make_Defining_Identifier
6987 (Sloc (Derived_Type), Chars (Derived_Type));
6988 Set_Is_Itype (Full_Der);
6989 Build_Itype_Reference (Full_Der, N);
6991 -- The full view will be used to swap entities on entry/exit to
6992 -- the body, and must appear in the entity list for the package.
6994 Append_Entity (Full_Der, Scope (Derived_Type));
6995 Set_Has_Private_Declaration (Full_Der);
6996 Set_Has_Private_Declaration (Derived_Type);
6997 Set_Associated_Node_For_Itype (Full_Der, N);
6998 Set_Parent (Full_Der, Parent (Derived_Type));
6999 Full_P := Full_View (Parent_Type);
7000 Exchange_Declarations (Parent_Type);
7002 Exchange_Declarations (Full_P);
7003 Set_Underlying_Full_View (Derived_Type, Full_Der);
7006 end Build_Derived_Private_Type;
7008 -------------------------------
7009 -- Build_Derived_Record_Type --
7010 -------------------------------
7014 -- Ideally we would like to use the same model of type derivation for
7015 -- tagged and untagged record types. Unfortunately this is not quite
7016 -- possible because the semantics of representation clauses is different
7017 -- for tagged and untagged records under inheritance. Consider the
7020 -- type R (...) is [tagged] record ... end record;
7021 -- type T (...) is new R (...) [with ...];
7023 -- The representation clauses for T can specify a completely different
7024 -- record layout from R's. Hence the same component can be placed in two
7025 -- very different positions in objects of type T and R. If R and T are
7026 -- tagged types, representation clauses for T can only specify the layout
7027 -- of non inherited components, thus components that are common in R and T
7028 -- have the same position in objects of type R and T.
7030 -- This has two implications. The first is that the entire tree for R's
7031 -- declaration needs to be copied for T in the untagged case, so that T
7032 -- can be viewed as a record type of its own with its own representation
7033 -- clauses. The second implication is the way we handle discriminants.
7034 -- Specifically, in the untagged case we need a way to communicate to Gigi
7035 -- what are the real discriminants in the record, while for the semantics
7036 -- we need to consider those introduced by the user to rename the
7037 -- discriminants in the parent type. This is handled by introducing the
7038 -- notion of stored discriminants. See below for more.
7040 -- Fortunately the way regular components are inherited can be handled in
7041 -- the same way in tagged and untagged types.
7043 -- To complicate things a bit more the private view of a private extension
7044 -- cannot be handled in the same way as the full view (for one thing the
7045 -- semantic rules are somewhat different). We will explain what differs
7048 -- 2. DISCRIMINANTS UNDER INHERITANCE
7050 -- The semantic rules governing the discriminants of derived types are
7053 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7054 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7056 -- If parent type has discriminants, then the discriminants that are
7057 -- declared in the derived type are [3.4 (11)]:
7059 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7062 -- o Otherwise, each discriminant of the parent type (implicitly declared
7063 -- in the same order with the same specifications). In this case, the
7064 -- discriminants are said to be "inherited", or if unknown in the parent
7065 -- are also unknown in the derived type.
7067 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7069 -- o The parent subtype shall be constrained;
7071 -- o If the parent type is not a tagged type, then each discriminant of
7072 -- the derived type shall be used in the constraint defining a parent
7073 -- subtype. [Implementation note: This ensures that the new discriminant
7074 -- can share storage with an existing discriminant.]
7076 -- For the derived type each discriminant of the parent type is either
7077 -- inherited, constrained to equal some new discriminant of the derived
7078 -- type, or constrained to the value of an expression.
7080 -- When inherited or constrained to equal some new discriminant, the
7081 -- parent discriminant and the discriminant of the derived type are said
7084 -- If a discriminant of the parent type is constrained to a specific value
7085 -- in the derived type definition, then the discriminant is said to be
7086 -- "specified" by that derived type definition.
7088 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7090 -- We have spoken about stored discriminants in point 1 (introduction)
7091 -- above. There are two sort of stored discriminants: implicit and
7092 -- explicit. As long as the derived type inherits the same discriminants as
7093 -- the root record type, stored discriminants are the same as regular
7094 -- discriminants, and are said to be implicit. However, if any discriminant
7095 -- in the root type was renamed in the derived type, then the derived
7096 -- type will contain explicit stored discriminants. Explicit stored
7097 -- discriminants are discriminants in addition to the semantically visible
7098 -- discriminants defined for the derived type. Stored discriminants are
7099 -- used by Gigi to figure out what are the physical discriminants in
7100 -- objects of the derived type (see precise definition in einfo.ads).
7101 -- As an example, consider the following:
7103 -- type R (D1, D2, D3 : Int) is record ... end record;
7104 -- type T1 is new R;
7105 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7106 -- type T3 is new T2;
7107 -- type T4 (Y : Int) is new T3 (Y, 99);
7109 -- The following table summarizes the discriminants and stored
7110 -- discriminants in R and T1 through T4.
7112 -- Type Discrim Stored Discrim Comment
7113 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7114 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7115 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7116 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7117 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7119 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7120 -- find the corresponding discriminant in the parent type, while
7121 -- Original_Record_Component (abbreviated ORC below), the actual physical
7122 -- component that is renamed. Finally the field Is_Completely_Hidden
7123 -- (abbreviated ICH below) is set for all explicit stored discriminants
7124 -- (see einfo.ads for more info). For the above example this gives:
7126 -- Discrim CD ORC ICH
7127 -- ^^^^^^^ ^^ ^^^ ^^^
7128 -- D1 in R empty itself no
7129 -- D2 in R empty itself no
7130 -- D3 in R empty itself no
7132 -- D1 in T1 D1 in R itself no
7133 -- D2 in T1 D2 in R itself no
7134 -- D3 in T1 D3 in R itself no
7136 -- X1 in T2 D3 in T1 D3 in T2 no
7137 -- X2 in T2 D1 in T1 D1 in T2 no
7138 -- D1 in T2 empty itself yes
7139 -- D2 in T2 empty itself yes
7140 -- D3 in T2 empty itself yes
7142 -- X1 in T3 X1 in T2 D3 in T3 no
7143 -- X2 in T3 X2 in T2 D1 in T3 no
7144 -- D1 in T3 empty itself yes
7145 -- D2 in T3 empty itself yes
7146 -- D3 in T3 empty itself yes
7148 -- Y in T4 X1 in T3 D3 in T3 no
7149 -- D1 in T3 empty itself yes
7150 -- D2 in T3 empty itself yes
7151 -- D3 in T3 empty itself yes
7153 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7155 -- Type derivation for tagged types is fairly straightforward. If no
7156 -- discriminants are specified by the derived type, these are inherited
7157 -- from the parent. No explicit stored discriminants are ever necessary.
7158 -- The only manipulation that is done to the tree is that of adding a
7159 -- _parent field with parent type and constrained to the same constraint
7160 -- specified for the parent in the derived type definition. For instance:
7162 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7163 -- type T1 is new R with null record;
7164 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7166 -- are changed into:
7168 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7169 -- _parent : R (D1, D2, D3);
7172 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7173 -- _parent : T1 (X2, 88, X1);
7176 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7177 -- ORC and ICH fields are:
7179 -- Discrim CD ORC ICH
7180 -- ^^^^^^^ ^^ ^^^ ^^^
7181 -- D1 in R empty itself no
7182 -- D2 in R empty itself no
7183 -- D3 in R empty itself no
7185 -- D1 in T1 D1 in R D1 in R no
7186 -- D2 in T1 D2 in R D2 in R no
7187 -- D3 in T1 D3 in R D3 in R no
7189 -- X1 in T2 D3 in T1 D3 in R no
7190 -- X2 in T2 D1 in T1 D1 in R no
7192 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7194 -- Regardless of whether we dealing with a tagged or untagged type
7195 -- we will transform all derived type declarations of the form
7197 -- type T is new R (...) [with ...];
7199 -- subtype S is R (...);
7200 -- type T is new S [with ...];
7202 -- type BT is new R [with ...];
7203 -- subtype T is BT (...);
7205 -- That is, the base derived type is constrained only if it has no
7206 -- discriminants. The reason for doing this is that GNAT's semantic model
7207 -- assumes that a base type with discriminants is unconstrained.
7209 -- Note that, strictly speaking, the above transformation is not always
7210 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7212 -- procedure B34011A is
7213 -- type REC (D : integer := 0) is record
7218 -- type T6 is new Rec;
7219 -- function F return T6;
7224 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7227 -- The definition of Q6.U is illegal. However transforming Q6.U into
7229 -- type BaseU is new T6;
7230 -- subtype U is BaseU (Q6.F.I)
7232 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7233 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7234 -- the transformation described above.
7236 -- There is another instance where the above transformation is incorrect.
7240 -- type Base (D : Integer) is tagged null record;
7241 -- procedure P (X : Base);
7243 -- type Der is new Base (2) with null record;
7244 -- procedure P (X : Der);
7247 -- Then the above transformation turns this into
7249 -- type Der_Base is new Base with null record;
7250 -- -- procedure P (X : Base) is implicitly inherited here
7251 -- -- as procedure P (X : Der_Base).
7253 -- subtype Der is Der_Base (2);
7254 -- procedure P (X : Der);
7255 -- -- The overriding of P (X : Der_Base) is illegal since we
7256 -- -- have a parameter conformance problem.
7258 -- To get around this problem, after having semantically processed Der_Base
7259 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7260 -- Discriminant_Constraint from Der so that when parameter conformance is
7261 -- checked when P is overridden, no semantic errors are flagged.
7263 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7265 -- Regardless of whether we are dealing with a tagged or untagged type
7266 -- we will transform all derived type declarations of the form
7268 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7269 -- type T is new R [with ...];
7271 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7273 -- The reason for such transformation is that it allows us to implement a
7274 -- very clean form of component inheritance as explained below.
7276 -- Note that this transformation is not achieved by direct tree rewriting
7277 -- and manipulation, but rather by redoing the semantic actions that the
7278 -- above transformation will entail. This is done directly in routine
7279 -- Inherit_Components.
7281 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7283 -- In both tagged and untagged derived types, regular non discriminant
7284 -- components are inherited in the derived type from the parent type. In
7285 -- the absence of discriminants component, inheritance is straightforward
7286 -- as components can simply be copied from the parent.
7288 -- If the parent has discriminants, inheriting components constrained with
7289 -- these discriminants requires caution. Consider the following example:
7291 -- type R (D1, D2 : Positive) is [tagged] record
7292 -- S : String (D1 .. D2);
7295 -- type T1 is new R [with null record];
7296 -- type T2 (X : positive) is new R (1, X) [with null record];
7298 -- As explained in 6. above, T1 is rewritten as
7299 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7300 -- which makes the treatment for T1 and T2 identical.
7302 -- What we want when inheriting S, is that references to D1 and D2 in R are
7303 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7304 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7305 -- with either discriminant references in the derived type or expressions.
7306 -- This replacement is achieved as follows: before inheriting R's
7307 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7308 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7309 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7310 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7311 -- by String (1 .. X).
7313 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7315 -- We explain here the rules governing private type extensions relevant to
7316 -- type derivation. These rules are explained on the following example:
7318 -- type D [(...)] is new A [(...)] with private; <-- partial view
7319 -- type D [(...)] is new P [(...)] with null record; <-- full view
7321 -- Type A is called the ancestor subtype of the private extension.
7322 -- Type P is the parent type of the full view of the private extension. It
7323 -- must be A or a type derived from A.
7325 -- The rules concerning the discriminants of private type extensions are
7328 -- o If a private extension inherits known discriminants from the ancestor
7329 -- subtype, then the full view shall also inherit its discriminants from
7330 -- the ancestor subtype and the parent subtype of the full view shall be
7331 -- constrained if and only if the ancestor subtype is constrained.
7333 -- o If a partial view has unknown discriminants, then the full view may
7334 -- define a definite or an indefinite subtype, with or without
7337 -- o If a partial view has neither known nor unknown discriminants, then
7338 -- the full view shall define a definite subtype.
7340 -- o If the ancestor subtype of a private extension has constrained
7341 -- discriminants, then the parent subtype of the full view shall impose a
7342 -- statically matching constraint on those discriminants.
7344 -- This means that only the following forms of private extensions are
7347 -- type D is new A with private; <-- partial view
7348 -- type D is new P with null record; <-- full view
7350 -- If A has no discriminants than P has no discriminants, otherwise P must
7351 -- inherit A's discriminants.
7353 -- type D is new A (...) with private; <-- partial view
7354 -- type D is new P (:::) with null record; <-- full view
7356 -- P must inherit A's discriminants and (...) and (:::) must statically
7359 -- subtype A is R (...);
7360 -- type D is new A with private; <-- partial view
7361 -- type D is new P with null record; <-- full view
7363 -- P must have inherited R's discriminants and must be derived from A or
7364 -- any of its subtypes.
7366 -- type D (..) is new A with private; <-- partial view
7367 -- type D (..) is new P [(:::)] with null record; <-- full view
7369 -- No specific constraints on P's discriminants or constraint (:::).
7370 -- Note that A can be unconstrained, but the parent subtype P must either
7371 -- be constrained or (:::) must be present.
7373 -- type D (..) is new A [(...)] with private; <-- partial view
7374 -- type D (..) is new P [(:::)] with null record; <-- full view
7376 -- P's constraints on A's discriminants must statically match those
7377 -- imposed by (...).
7379 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7381 -- The full view of a private extension is handled exactly as described
7382 -- above. The model chose for the private view of a private extension is
7383 -- the same for what concerns discriminants (i.e. they receive the same
7384 -- treatment as in the tagged case). However, the private view of the
7385 -- private extension always inherits the components of the parent base,
7386 -- without replacing any discriminant reference. Strictly speaking this is
7387 -- incorrect. However, Gigi never uses this view to generate code so this
7388 -- is a purely semantic issue. In theory, a set of transformations similar
7389 -- to those given in 5. and 6. above could be applied to private views of
7390 -- private extensions to have the same model of component inheritance as
7391 -- for non private extensions. However, this is not done because it would
7392 -- further complicate private type processing. Semantically speaking, this
7393 -- leaves us in an uncomfortable situation. As an example consider:
7396 -- type R (D : integer) is tagged record
7397 -- S : String (1 .. D);
7399 -- procedure P (X : R);
7400 -- type T is new R (1) with private;
7402 -- type T is new R (1) with null record;
7405 -- This is transformed into:
7408 -- type R (D : integer) is tagged record
7409 -- S : String (1 .. D);
7411 -- procedure P (X : R);
7412 -- type T is new R (1) with private;
7414 -- type BaseT is new R with null record;
7415 -- subtype T is BaseT (1);
7418 -- (strictly speaking the above is incorrect Ada)
7420 -- From the semantic standpoint the private view of private extension T
7421 -- should be flagged as constrained since one can clearly have
7425 -- in a unit withing Pack. However, when deriving subprograms for the
7426 -- private view of private extension T, T must be seen as unconstrained
7427 -- since T has discriminants (this is a constraint of the current
7428 -- subprogram derivation model). Thus, when processing the private view of
7429 -- a private extension such as T, we first mark T as unconstrained, we
7430 -- process it, we perform program derivation and just before returning from
7431 -- Build_Derived_Record_Type we mark T as constrained.
7433 -- ??? Are there are other uncomfortable cases that we will have to
7436 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7438 -- Types that are derived from a visible record type and have a private
7439 -- extension present other peculiarities. They behave mostly like private
7440 -- types, but if they have primitive operations defined, these will not
7441 -- have the proper signatures for further inheritance, because other
7442 -- primitive operations will use the implicit base that we define for
7443 -- private derivations below. This affect subprogram inheritance (see
7444 -- Derive_Subprograms for details). We also derive the implicit base from
7445 -- the base type of the full view, so that the implicit base is a record
7446 -- type and not another private type, This avoids infinite loops.
7448 procedure Build_Derived_Record_Type
7450 Parent_Type : Entity_Id;
7451 Derived_Type : Entity_Id;
7452 Derive_Subps : Boolean := True)
7454 Discriminant_Specs : constant Boolean :=
7455 Present (Discriminant_Specifications (N));
7456 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7457 Loc : constant Source_Ptr := Sloc (N);
7458 Private_Extension : constant Boolean :=
7459 Nkind (N) = N_Private_Extension_Declaration;
7460 Assoc_List : Elist_Id;
7461 Constraint_Present : Boolean;
7463 Discrim : Entity_Id;
7465 Inherit_Discrims : Boolean := False;
7466 Last_Discrim : Entity_Id;
7467 New_Base : Entity_Id;
7469 New_Discrs : Elist_Id;
7470 New_Indic : Node_Id;
7471 Parent_Base : Entity_Id;
7472 Save_Etype : Entity_Id;
7473 Save_Discr_Constr : Elist_Id;
7474 Save_Next_Entity : Entity_Id;
7477 Discs : Elist_Id := New_Elmt_List;
7478 -- An empty Discs list means that there were no constraints in the
7479 -- subtype indication or that there was an error processing it.
7482 if Ekind (Parent_Type) = E_Record_Type_With_Private
7483 and then Present (Full_View (Parent_Type))
7484 and then Has_Discriminants (Parent_Type)
7486 Parent_Base := Base_Type (Full_View (Parent_Type));
7488 Parent_Base := Base_Type (Parent_Type);
7491 -- AI05-0115 : if this is a derivation from a private type in some
7492 -- other scope that may lead to invisible components for the derived
7493 -- type, mark it accordingly.
7495 if Is_Private_Type (Parent_Type) then
7496 if Scope (Parent_Type) = Scope (Derived_Type) then
7499 elsif In_Open_Scopes (Scope (Parent_Type))
7500 and then In_Private_Part (Scope (Parent_Type))
7505 Set_Has_Private_Ancestor (Derived_Type);
7509 Set_Has_Private_Ancestor
7510 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7513 -- Before we start the previously documented transformations, here is
7514 -- little fix for size and alignment of tagged types. Normally when we
7515 -- derive type D from type P, we copy the size and alignment of P as the
7516 -- default for D, and in the absence of explicit representation clauses
7517 -- for D, the size and alignment are indeed the same as the parent.
7519 -- But this is wrong for tagged types, since fields may be added, and
7520 -- the default size may need to be larger, and the default alignment may
7521 -- need to be larger.
7523 -- We therefore reset the size and alignment fields in the tagged case.
7524 -- Note that the size and alignment will in any case be at least as
7525 -- large as the parent type (since the derived type has a copy of the
7526 -- parent type in the _parent field)
7528 -- The type is also marked as being tagged here, which is needed when
7529 -- processing components with a self-referential anonymous access type
7530 -- in the call to Check_Anonymous_Access_Components below. Note that
7531 -- this flag is also set later on for completeness.
7534 Set_Is_Tagged_Type (Derived_Type);
7535 Init_Size_Align (Derived_Type);
7538 -- STEP 0a: figure out what kind of derived type declaration we have
7540 if Private_Extension then
7542 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7543 Set_Default_SSO (Derived_Type);
7546 Type_Def := Type_Definition (N);
7548 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7549 -- Parent_Base can be a private type or private extension. However,
7550 -- for tagged types with an extension the newly added fields are
7551 -- visible and hence the Derived_Type is always an E_Record_Type.
7552 -- (except that the parent may have its own private fields).
7553 -- For untagged types we preserve the Ekind of the Parent_Base.
7555 if Present (Record_Extension_Part (Type_Def)) then
7556 Set_Ekind (Derived_Type, E_Record_Type);
7557 Set_Default_SSO (Derived_Type);
7559 -- Create internal access types for components with anonymous
7562 if Ada_Version >= Ada_2005 then
7563 Check_Anonymous_Access_Components
7564 (N, Derived_Type, Derived_Type,
7565 Component_List (Record_Extension_Part (Type_Def)));
7569 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7573 -- Indic can either be an N_Identifier if the subtype indication
7574 -- contains no constraint or an N_Subtype_Indication if the subtype
7575 -- indication has a constraint.
7577 Indic := Subtype_Indication (Type_Def);
7578 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7580 -- Check that the type has visible discriminants. The type may be
7581 -- a private type with unknown discriminants whose full view has
7582 -- discriminants which are invisible.
7584 if Constraint_Present then
7585 if not Has_Discriminants (Parent_Base)
7587 (Has_Unknown_Discriminants (Parent_Base)
7588 and then Is_Private_Type (Parent_Base))
7591 ("invalid constraint: type has no discriminant",
7592 Constraint (Indic));
7594 Constraint_Present := False;
7595 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7597 elsif Is_Constrained (Parent_Type) then
7599 ("invalid constraint: parent type is already constrained",
7600 Constraint (Indic));
7602 Constraint_Present := False;
7603 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7607 -- STEP 0b: If needed, apply transformation given in point 5. above
7609 if not Private_Extension
7610 and then Has_Discriminants (Parent_Type)
7611 and then not Discriminant_Specs
7612 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7614 -- First, we must analyze the constraint (see comment in point 5.)
7615 -- The constraint may come from the subtype indication of the full
7618 if Constraint_Present then
7619 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7621 -- If there is no explicit constraint, there might be one that is
7622 -- inherited from a constrained parent type. In that case verify that
7623 -- it conforms to the constraint in the partial view. In perverse
7624 -- cases the parent subtypes of the partial and full view can have
7625 -- different constraints.
7627 elsif Present (Stored_Constraint (Parent_Type)) then
7628 New_Discrs := Stored_Constraint (Parent_Type);
7631 New_Discrs := No_Elist;
7634 if Has_Discriminants (Derived_Type)
7635 and then Has_Private_Declaration (Derived_Type)
7636 and then Present (Discriminant_Constraint (Derived_Type))
7637 and then Present (New_Discrs)
7639 -- Verify that constraints of the full view statically match
7640 -- those given in the partial view.
7646 C1 := First_Elmt (New_Discrs);
7647 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7648 while Present (C1) and then Present (C2) loop
7649 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7651 (Is_OK_Static_Expression (Node (C1))
7652 and then Is_OK_Static_Expression (Node (C2))
7654 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7659 if Constraint_Present then
7661 ("constraint not conformant to previous declaration",
7665 ("constraint of full view is incompatible "
7666 & "with partial view", N);
7676 -- Insert and analyze the declaration for the unconstrained base type
7678 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7681 Make_Full_Type_Declaration (Loc,
7682 Defining_Identifier => New_Base,
7684 Make_Derived_Type_Definition (Loc,
7685 Abstract_Present => Abstract_Present (Type_Def),
7686 Limited_Present => Limited_Present (Type_Def),
7687 Subtype_Indication =>
7688 New_Occurrence_Of (Parent_Base, Loc),
7689 Record_Extension_Part =>
7690 Relocate_Node (Record_Extension_Part (Type_Def)),
7691 Interface_List => Interface_List (Type_Def)));
7693 Set_Parent (New_Decl, Parent (N));
7694 Mark_Rewrite_Insertion (New_Decl);
7695 Insert_Before (N, New_Decl);
7697 -- In the extension case, make sure ancestor is frozen appropriately
7698 -- (see also non-discriminated case below).
7700 if Present (Record_Extension_Part (Type_Def))
7701 or else Is_Interface (Parent_Base)
7703 Freeze_Before (New_Decl, Parent_Type);
7706 -- Note that this call passes False for the Derive_Subps parameter
7707 -- because subprogram derivation is deferred until after creating
7708 -- the subtype (see below).
7711 (New_Decl, Parent_Base, New_Base,
7712 Is_Completion => True, Derive_Subps => False);
7714 -- ??? This needs re-examination to determine whether the
7715 -- above call can simply be replaced by a call to Analyze.
7717 Set_Analyzed (New_Decl);
7719 -- Insert and analyze the declaration for the constrained subtype
7721 if Constraint_Present then
7723 Make_Subtype_Indication (Loc,
7724 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7725 Constraint => Relocate_Node (Constraint (Indic)));
7729 Constr_List : constant List_Id := New_List;
7734 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7735 while Present (C) loop
7738 -- It is safe here to call New_Copy_Tree since
7739 -- Force_Evaluation was called on each constraint in
7740 -- Build_Discriminant_Constraints.
7742 Append (New_Copy_Tree (Expr), To => Constr_List);
7748 Make_Subtype_Indication (Loc,
7749 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7751 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7756 Make_Subtype_Declaration (Loc,
7757 Defining_Identifier => Derived_Type,
7758 Subtype_Indication => New_Indic));
7762 -- Derivation of subprograms must be delayed until the full subtype
7763 -- has been established, to ensure proper overriding of subprograms
7764 -- inherited by full types. If the derivations occurred as part of
7765 -- the call to Build_Derived_Type above, then the check for type
7766 -- conformance would fail because earlier primitive subprograms
7767 -- could still refer to the full type prior the change to the new
7768 -- subtype and hence would not match the new base type created here.
7769 -- Subprograms are not derived, however, when Derive_Subps is False
7770 -- (since otherwise there could be redundant derivations).
7772 if Derive_Subps then
7773 Derive_Subprograms (Parent_Type, Derived_Type);
7776 -- For tagged types the Discriminant_Constraint of the new base itype
7777 -- is inherited from the first subtype so that no subtype conformance
7778 -- problem arise when the first subtype overrides primitive
7779 -- operations inherited by the implicit base type.
7782 Set_Discriminant_Constraint
7783 (New_Base, Discriminant_Constraint (Derived_Type));
7789 -- If we get here Derived_Type will have no discriminants or it will be
7790 -- a discriminated unconstrained base type.
7792 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7796 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7797 -- The declaration of a specific descendant of an interface type
7798 -- freezes the interface type (RM 13.14).
7800 if not Private_Extension or else Is_Interface (Parent_Base) then
7801 Freeze_Before (N, Parent_Type);
7804 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7805 -- cannot be declared at a deeper level than its parent type is
7806 -- removed. The check on derivation within a generic body is also
7807 -- relaxed, but there's a restriction that a derived tagged type
7808 -- cannot be declared in a generic body if it's derived directly
7809 -- or indirectly from a formal type of that generic.
7811 if Ada_Version >= Ada_2005 then
7812 if Present (Enclosing_Generic_Body (Derived_Type)) then
7814 Ancestor_Type : Entity_Id;
7817 -- Check to see if any ancestor of the derived type is a
7820 Ancestor_Type := Parent_Type;
7821 while not Is_Generic_Type (Ancestor_Type)
7822 and then Etype (Ancestor_Type) /= Ancestor_Type
7824 Ancestor_Type := Etype (Ancestor_Type);
7827 -- If the derived type does have a formal type as an
7828 -- ancestor, then it's an error if the derived type is
7829 -- declared within the body of the generic unit that
7830 -- declares the formal type in its generic formal part. It's
7831 -- sufficient to check whether the ancestor type is declared
7832 -- inside the same generic body as the derived type (such as
7833 -- within a nested generic spec), in which case the
7834 -- derivation is legal. If the formal type is declared
7835 -- outside of that generic body, then it's guaranteed that
7836 -- the derived type is declared within the generic body of
7837 -- the generic unit declaring the formal type.
7839 if Is_Generic_Type (Ancestor_Type)
7840 and then Enclosing_Generic_Body (Ancestor_Type) /=
7841 Enclosing_Generic_Body (Derived_Type)
7844 ("parent type of& must not be descendant of formal type"
7845 & " of an enclosing generic body",
7846 Indic, Derived_Type);
7851 elsif Type_Access_Level (Derived_Type) /=
7852 Type_Access_Level (Parent_Type)
7853 and then not Is_Generic_Type (Derived_Type)
7855 if Is_Controlled (Parent_Type) then
7857 ("controlled type must be declared at the library level",
7861 ("type extension at deeper accessibility level than parent",
7867 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7870 and then GB /= Enclosing_Generic_Body (Parent_Base)
7873 ("parent type of& must not be outside generic body"
7875 Indic, Derived_Type);
7881 -- Ada 2005 (AI-251)
7883 if Ada_Version >= Ada_2005 and then Is_Tagged then
7885 -- "The declaration of a specific descendant of an interface type
7886 -- freezes the interface type" (RM 13.14).
7891 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7892 Iface := First (Interface_List (Type_Def));
7893 while Present (Iface) loop
7894 Freeze_Before (N, Etype (Iface));
7901 -- STEP 1b : preliminary cleanup of the full view of private types
7903 -- If the type is already marked as having discriminants, then it's the
7904 -- completion of a private type or private extension and we need to
7905 -- retain the discriminants from the partial view if the current
7906 -- declaration has Discriminant_Specifications so that we can verify
7907 -- conformance. However, we must remove any existing components that
7908 -- were inherited from the parent (and attached in Copy_And_Swap)
7909 -- because the full type inherits all appropriate components anyway, and
7910 -- we do not want the partial view's components interfering.
7912 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7913 Discrim := First_Discriminant (Derived_Type);
7915 Last_Discrim := Discrim;
7916 Next_Discriminant (Discrim);
7917 exit when No (Discrim);
7920 Set_Last_Entity (Derived_Type, Last_Discrim);
7922 -- In all other cases wipe out the list of inherited components (even
7923 -- inherited discriminants), it will be properly rebuilt here.
7926 Set_First_Entity (Derived_Type, Empty);
7927 Set_Last_Entity (Derived_Type, Empty);
7930 -- STEP 1c: Initialize some flags for the Derived_Type
7932 -- The following flags must be initialized here so that
7933 -- Process_Discriminants can check that discriminants of tagged types do
7934 -- not have a default initial value and that access discriminants are
7935 -- only specified for limited records. For completeness, these flags are
7936 -- also initialized along with all the other flags below.
7938 -- AI-419: Limitedness is not inherited from an interface parent, so to
7939 -- be limited in that case the type must be explicitly declared as
7940 -- limited. However, task and protected interfaces are always limited.
7942 if Limited_Present (Type_Def) then
7943 Set_Is_Limited_Record (Derived_Type);
7945 elsif Is_Limited_Record (Parent_Type)
7946 or else (Present (Full_View (Parent_Type))
7947 and then Is_Limited_Record (Full_View (Parent_Type)))
7949 if not Is_Interface (Parent_Type)
7950 or else Is_Synchronized_Interface (Parent_Type)
7951 or else Is_Protected_Interface (Parent_Type)
7952 or else Is_Task_Interface (Parent_Type)
7954 Set_Is_Limited_Record (Derived_Type);
7958 -- STEP 2a: process discriminants of derived type if any
7960 Push_Scope (Derived_Type);
7962 if Discriminant_Specs then
7963 Set_Has_Unknown_Discriminants (Derived_Type, False);
7965 -- The following call initializes fields Has_Discriminants and
7966 -- Discriminant_Constraint, unless we are processing the completion
7967 -- of a private type declaration.
7969 Check_Or_Process_Discriminants (N, Derived_Type);
7971 -- For untagged types, the constraint on the Parent_Type must be
7972 -- present and is used to rename the discriminants.
7974 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7975 Error_Msg_N ("untagged parent must have discriminants", Indic);
7977 elsif not Is_Tagged and then not Constraint_Present then
7979 ("discriminant constraint needed for derived untagged records",
7982 -- Otherwise the parent subtype must be constrained unless we have a
7983 -- private extension.
7985 elsif not Constraint_Present
7986 and then not Private_Extension
7987 and then not Is_Constrained (Parent_Type)
7990 ("unconstrained type not allowed in this context", Indic);
7992 elsif Constraint_Present then
7993 -- The following call sets the field Corresponding_Discriminant
7994 -- for the discriminants in the Derived_Type.
7996 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7998 -- For untagged types all new discriminants must rename
7999 -- discriminants in the parent. For private extensions new
8000 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8002 Discrim := First_Discriminant (Derived_Type);
8003 while Present (Discrim) loop
8005 and then No (Corresponding_Discriminant (Discrim))
8008 ("new discriminants must constrain old ones", Discrim);
8010 elsif Private_Extension
8011 and then Present (Corresponding_Discriminant (Discrim))
8014 ("only static constraints allowed for parent"
8015 & " discriminants in the partial view", Indic);
8019 -- If a new discriminant is used in the constraint, then its
8020 -- subtype must be statically compatible with the parent
8021 -- discriminant's subtype (3.7(15)).
8023 -- However, if the record contains an array constrained by
8024 -- the discriminant but with some different bound, the compiler
8025 -- attemps to create a smaller range for the discriminant type.
8026 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8027 -- the discriminant type is a scalar type, the check must use
8028 -- the original discriminant type in the parent declaration.
8031 Corr_Disc : constant Entity_Id :=
8032 Corresponding_Discriminant (Discrim);
8033 Disc_Type : constant Entity_Id := Etype (Discrim);
8034 Corr_Type : Entity_Id;
8037 if Present (Corr_Disc) then
8038 if Is_Scalar_Type (Disc_Type) then
8040 Entity (Discriminant_Type (Parent (Corr_Disc)));
8042 Corr_Type := Etype (Corr_Disc);
8046 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8049 ("subtype must be compatible "
8050 & "with parent discriminant",
8056 Next_Discriminant (Discrim);
8059 -- Check whether the constraints of the full view statically
8060 -- match those imposed by the parent subtype [7.3(13)].
8062 if Present (Stored_Constraint (Derived_Type)) then
8067 C1 := First_Elmt (Discs);
8068 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8069 while Present (C1) and then Present (C2) loop
8071 Fully_Conformant_Expressions (Node (C1), Node (C2))
8074 ("not conformant with previous declaration",
8085 -- STEP 2b: No new discriminants, inherit discriminants if any
8088 if Private_Extension then
8089 Set_Has_Unknown_Discriminants
8091 Has_Unknown_Discriminants (Parent_Type)
8092 or else Unknown_Discriminants_Present (N));
8094 -- The partial view of the parent may have unknown discriminants,
8095 -- but if the full view has discriminants and the parent type is
8096 -- in scope they must be inherited.
8098 elsif Has_Unknown_Discriminants (Parent_Type)
8100 (not Has_Discriminants (Parent_Type)
8101 or else not In_Open_Scopes (Scope (Parent_Type)))
8103 Set_Has_Unknown_Discriminants (Derived_Type);
8106 if not Has_Unknown_Discriminants (Derived_Type)
8107 and then not Has_Unknown_Discriminants (Parent_Base)
8108 and then Has_Discriminants (Parent_Type)
8110 Inherit_Discrims := True;
8111 Set_Has_Discriminants
8112 (Derived_Type, True);
8113 Set_Discriminant_Constraint
8114 (Derived_Type, Discriminant_Constraint (Parent_Base));
8117 -- The following test is true for private types (remember
8118 -- transformation 5. is not applied to those) and in an error
8121 if Constraint_Present then
8122 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8125 -- For now mark a new derived type as constrained only if it has no
8126 -- discriminants. At the end of Build_Derived_Record_Type we properly
8127 -- set this flag in the case of private extensions. See comments in
8128 -- point 9. just before body of Build_Derived_Record_Type.
8132 not (Inherit_Discrims
8133 or else Has_Unknown_Discriminants (Derived_Type)));
8136 -- STEP 3: initialize fields of derived type
8138 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8139 Set_Stored_Constraint (Derived_Type, No_Elist);
8141 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8142 -- but cannot be interfaces
8144 if not Private_Extension
8145 and then Ekind (Derived_Type) /= E_Private_Type
8146 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8148 if Interface_Present (Type_Def) then
8149 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8152 Set_Interfaces (Derived_Type, No_Elist);
8155 -- Fields inherited from the Parent_Type
8157 Set_Has_Specified_Layout
8158 (Derived_Type, Has_Specified_Layout (Parent_Type));
8159 Set_Is_Limited_Composite
8160 (Derived_Type, Is_Limited_Composite (Parent_Type));
8161 Set_Is_Private_Composite
8162 (Derived_Type, Is_Private_Composite (Parent_Type));
8164 -- Fields inherited from the Parent_Base
8166 Set_Has_Controlled_Component
8167 (Derived_Type, Has_Controlled_Component (Parent_Base));
8168 Set_Has_Non_Standard_Rep
8169 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8170 Set_Has_Primitive_Operations
8171 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8173 -- Fields inherited from the Parent_Base in the non-private case
8175 if Ekind (Derived_Type) = E_Record_Type then
8176 Set_Has_Complex_Representation
8177 (Derived_Type, Has_Complex_Representation (Parent_Base));
8180 -- Fields inherited from the Parent_Base for record types
8182 if Is_Record_Type (Derived_Type) then
8185 Parent_Full : Entity_Id;
8188 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8189 -- Parent_Base can be a private type or private extension. Go
8190 -- to the full view here to get the E_Record_Type specific flags.
8192 if Present (Full_View (Parent_Base)) then
8193 Parent_Full := Full_View (Parent_Base);
8195 Parent_Full := Parent_Base;
8198 Set_OK_To_Reorder_Components
8199 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8203 -- Set fields for private derived types
8205 if Is_Private_Type (Derived_Type) then
8206 Set_Depends_On_Private (Derived_Type, True);
8207 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8209 -- Inherit fields from non private record types. If this is the
8210 -- completion of a derivation from a private type, the parent itself
8211 -- is private, and the attributes come from its full view, which must
8215 if Is_Private_Type (Parent_Base)
8216 and then not Is_Record_Type (Parent_Base)
8218 Set_Component_Alignment
8219 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8221 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8223 Set_Component_Alignment
8224 (Derived_Type, Component_Alignment (Parent_Base));
8226 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8230 -- Set fields for tagged types
8233 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8235 -- All tagged types defined in Ada.Finalization are controlled
8237 if Chars (Scope (Derived_Type)) = Name_Finalization
8238 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8239 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8241 Set_Is_Controlled (Derived_Type);
8243 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8246 -- Minor optimization: there is no need to generate the class-wide
8247 -- entity associated with an underlying record view.
8249 if not Is_Underlying_Record_View (Derived_Type) then
8250 Make_Class_Wide_Type (Derived_Type);
8253 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8255 if Has_Discriminants (Derived_Type)
8256 and then Constraint_Present
8258 Set_Stored_Constraint
8259 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8262 if Ada_Version >= Ada_2005 then
8264 Ifaces_List : Elist_Id;
8267 -- Checks rules 3.9.4 (13/2 and 14/2)
8269 if Comes_From_Source (Derived_Type)
8270 and then not Is_Private_Type (Derived_Type)
8271 and then Is_Interface (Parent_Type)
8272 and then not Is_Interface (Derived_Type)
8274 if Is_Task_Interface (Parent_Type) then
8276 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8279 elsif Is_Protected_Interface (Parent_Type) then
8281 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8286 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8288 Check_Interfaces (N, Type_Def);
8290 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8291 -- not already in the parents.
8295 Ifaces_List => Ifaces_List,
8296 Exclude_Parents => True);
8298 Set_Interfaces (Derived_Type, Ifaces_List);
8300 -- If the derived type is the anonymous type created for
8301 -- a declaration whose parent has a constraint, propagate
8302 -- the interface list to the source type. This must be done
8303 -- prior to the completion of the analysis of the source type
8304 -- because the components in the extension may contain current
8305 -- instances whose legality depends on some ancestor.
8307 if Is_Itype (Derived_Type) then
8309 Def : constant Node_Id :=
8310 Associated_Node_For_Itype (Derived_Type);
8313 and then Nkind (Def) = N_Full_Type_Declaration
8316 (Defining_Identifier (Def), Ifaces_List);
8324 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8325 Set_Has_Non_Standard_Rep
8326 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8329 -- STEP 4: Inherit components from the parent base and constrain them.
8330 -- Apply the second transformation described in point 6. above.
8332 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8333 or else not Has_Discriminants (Parent_Type)
8334 or else not Is_Constrained (Parent_Type)
8338 Constrs := Discriminant_Constraint (Parent_Type);
8343 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8345 -- STEP 5a: Copy the parent record declaration for untagged types
8347 if not Is_Tagged then
8349 -- Discriminant_Constraint (Derived_Type) has been properly
8350 -- constructed. Save it and temporarily set it to Empty because we
8351 -- do not want the call to New_Copy_Tree below to mess this list.
8353 if Has_Discriminants (Derived_Type) then
8354 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8355 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8357 Save_Discr_Constr := No_Elist;
8360 -- Save the Etype field of Derived_Type. It is correctly set now,
8361 -- but the call to New_Copy tree may remap it to point to itself,
8362 -- which is not what we want. Ditto for the Next_Entity field.
8364 Save_Etype := Etype (Derived_Type);
8365 Save_Next_Entity := Next_Entity (Derived_Type);
8367 -- Assoc_List maps all stored discriminants in the Parent_Base to
8368 -- stored discriminants in the Derived_Type. It is fundamental that
8369 -- no types or itypes with discriminants other than the stored
8370 -- discriminants appear in the entities declared inside
8371 -- Derived_Type, since the back end cannot deal with it.
8375 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8377 -- Restore the fields saved prior to the New_Copy_Tree call
8378 -- and compute the stored constraint.
8380 Set_Etype (Derived_Type, Save_Etype);
8381 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8383 if Has_Discriminants (Derived_Type) then
8384 Set_Discriminant_Constraint
8385 (Derived_Type, Save_Discr_Constr);
8386 Set_Stored_Constraint
8387 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8388 Replace_Components (Derived_Type, New_Decl);
8389 Set_Has_Implicit_Dereference
8390 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8393 -- Insert the new derived type declaration
8395 Rewrite (N, New_Decl);
8397 -- STEP 5b: Complete the processing for record extensions in generics
8399 -- There is no completion for record extensions declared in the
8400 -- parameter part of a generic, so we need to complete processing for
8401 -- these generic record extensions here. The Record_Type_Definition call
8402 -- will change the Ekind of the components from E_Void to E_Component.
8404 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8405 Record_Type_Definition (Empty, Derived_Type);
8407 -- STEP 5c: Process the record extension for non private tagged types
8409 elsif not Private_Extension then
8411 -- Add the _parent field in the derived type. In ASIS mode there is
8412 -- not enough semantic information for full expansion, but set the
8413 -- parent subtype to allow resolution of selected components in
8417 Set_Parent_Subtype (Derived_Type, Parent_Type);
8419 Expand_Record_Extension (Derived_Type, Type_Def);
8422 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8423 -- implemented interfaces if we are in expansion mode
8426 and then Has_Interfaces (Derived_Type)
8428 Add_Interface_Tag_Components (N, Derived_Type);
8431 -- Analyze the record extension
8433 Record_Type_Definition
8434 (Record_Extension_Part (Type_Def), Derived_Type);
8439 -- Nothing else to do if there is an error in the derivation.
8440 -- An unusual case: the full view may be derived from a type in an
8441 -- instance, when the partial view was used illegally as an actual
8442 -- in that instance, leading to a circular definition.
8444 if Etype (Derived_Type) = Any_Type
8445 or else Etype (Parent_Type) = Derived_Type
8450 -- Set delayed freeze and then derive subprograms, we need to do
8451 -- this in this order so that derived subprograms inherit the
8452 -- derived freeze if necessary.
8454 Set_Has_Delayed_Freeze (Derived_Type);
8456 if Derive_Subps then
8457 Derive_Subprograms (Parent_Type, Derived_Type);
8460 -- If we have a private extension which defines a constrained derived
8461 -- type mark as constrained here after we have derived subprograms. See
8462 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8464 if Private_Extension and then Inherit_Discrims then
8465 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8466 Set_Is_Constrained (Derived_Type, True);
8467 Set_Discriminant_Constraint (Derived_Type, Discs);
8469 elsif Is_Constrained (Parent_Type) then
8471 (Derived_Type, True);
8472 Set_Discriminant_Constraint
8473 (Derived_Type, Discriminant_Constraint (Parent_Type));
8477 -- Update the class-wide type, which shares the now-completed entity
8478 -- list with its specific type. In case of underlying record views,
8479 -- we do not generate the corresponding class wide entity.
8482 and then not Is_Underlying_Record_View (Derived_Type)
8485 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8487 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8490 Check_Function_Writable_Actuals (N);
8491 end Build_Derived_Record_Type;
8493 ------------------------
8494 -- Build_Derived_Type --
8495 ------------------------
8497 procedure Build_Derived_Type
8499 Parent_Type : Entity_Id;
8500 Derived_Type : Entity_Id;
8501 Is_Completion : Boolean;
8502 Derive_Subps : Boolean := True)
8504 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8507 -- Set common attributes
8509 Set_Scope (Derived_Type, Current_Scope);
8511 Set_Etype (Derived_Type, Parent_Base);
8512 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8513 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8514 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8516 Set_Size_Info (Derived_Type, Parent_Type);
8517 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8518 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8519 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8521 -- If the parent has primitive routines, set the derived type link
8523 if Has_Primitive_Operations (Parent_Type) then
8524 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8527 -- If the parent type is a private subtype, the convention on the base
8528 -- type may be set in the private part, and not propagated to the
8529 -- subtype until later, so we obtain the convention from the base type.
8531 Set_Convention (Derived_Type, Convention (Parent_Base));
8533 -- Set SSO default for record or array type
8535 if (Is_Array_Type (Derived_Type)
8536 or else Is_Record_Type (Derived_Type))
8537 and then Is_Base_Type (Derived_Type)
8539 Set_Default_SSO (Derived_Type);
8542 -- Propagate invariant information. The new type has invariants if
8543 -- they are inherited from the parent type, and these invariants can
8544 -- be further inherited, so both flags are set.
8546 -- We similarly inherit predicates
8548 if Has_Predicates (Parent_Type) then
8549 Set_Has_Predicates (Derived_Type);
8552 -- The derived type inherits the representation clauses of the parent.
8553 -- However, for a private type that is completed by a derivation, there
8554 -- may be operation attributes that have been specified already (stream
8555 -- attributes and External_Tag) and those must be provided. Finally,
8556 -- if the partial view is a private extension, the representation items
8557 -- of the parent have been inherited already, and should not be chained
8558 -- twice to the derived type.
8560 if Is_Tagged_Type (Parent_Type)
8561 and then Present (First_Rep_Item (Derived_Type))
8563 -- The existing items are either operational items or items inherited
8564 -- from a private extension declaration.
8568 -- Used to iterate over representation items of the derived type
8571 -- Last representation item of the (non-empty) representation
8572 -- item list of the derived type.
8574 Found : Boolean := False;
8577 Rep := First_Rep_Item (Derived_Type);
8579 while Present (Rep) loop
8580 if Rep = First_Rep_Item (Parent_Type) then
8585 Rep := Next_Rep_Item (Rep);
8587 if Present (Rep) then
8593 -- Here if we either encountered the parent type's first rep
8594 -- item on the derived type's rep item list (in which case
8595 -- Found is True, and we have nothing else to do), or if we
8596 -- reached the last rep item of the derived type, which is
8597 -- Last_Rep, in which case we further chain the parent type's
8598 -- rep items to those of the derived type.
8601 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8606 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8609 -- If the parent type has delayed rep aspects, then mark the derived
8610 -- type as possibly inheriting a delayed rep aspect.
8612 if Has_Delayed_Rep_Aspects (Parent_Type) then
8613 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8616 -- Type dependent processing
8618 case Ekind (Parent_Type) is
8619 when Numeric_Kind =>
8620 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8623 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8627 | Class_Wide_Kind =>
8628 Build_Derived_Record_Type
8629 (N, Parent_Type, Derived_Type, Derive_Subps);
8632 when Enumeration_Kind =>
8633 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8636 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8638 when Incomplete_Or_Private_Kind =>
8639 Build_Derived_Private_Type
8640 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8642 -- For discriminated types, the derivation includes deriving
8643 -- primitive operations. For others it is done below.
8645 if Is_Tagged_Type (Parent_Type)
8646 or else Has_Discriminants (Parent_Type)
8647 or else (Present (Full_View (Parent_Type))
8648 and then Has_Discriminants (Full_View (Parent_Type)))
8653 when Concurrent_Kind =>
8654 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8657 raise Program_Error;
8660 -- Nothing more to do if some error occurred
8662 if Etype (Derived_Type) = Any_Type then
8666 -- Set delayed freeze and then derive subprograms, we need to do this
8667 -- in this order so that derived subprograms inherit the derived freeze
8670 Set_Has_Delayed_Freeze (Derived_Type);
8672 if Derive_Subps then
8673 Derive_Subprograms (Parent_Type, Derived_Type);
8676 Set_Has_Primitive_Operations
8677 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8678 end Build_Derived_Type;
8680 -----------------------
8681 -- Build_Discriminal --
8682 -----------------------
8684 procedure Build_Discriminal (Discrim : Entity_Id) is
8685 D_Minal : Entity_Id;
8686 CR_Disc : Entity_Id;
8689 -- A discriminal has the same name as the discriminant
8691 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8693 Set_Ekind (D_Minal, E_In_Parameter);
8694 Set_Mechanism (D_Minal, Default_Mechanism);
8695 Set_Etype (D_Minal, Etype (Discrim));
8696 Set_Scope (D_Minal, Current_Scope);
8698 Set_Discriminal (Discrim, D_Minal);
8699 Set_Discriminal_Link (D_Minal, Discrim);
8701 -- For task types, build at once the discriminants of the corresponding
8702 -- record, which are needed if discriminants are used in entry defaults
8703 -- and in family bounds.
8705 if Is_Concurrent_Type (Current_Scope)
8706 or else Is_Limited_Type (Current_Scope)
8708 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8710 Set_Ekind (CR_Disc, E_In_Parameter);
8711 Set_Mechanism (CR_Disc, Default_Mechanism);
8712 Set_Etype (CR_Disc, Etype (Discrim));
8713 Set_Scope (CR_Disc, Current_Scope);
8714 Set_Discriminal_Link (CR_Disc, Discrim);
8715 Set_CR_Discriminant (Discrim, CR_Disc);
8717 end Build_Discriminal;
8719 ------------------------------------
8720 -- Build_Discriminant_Constraints --
8721 ------------------------------------
8723 function Build_Discriminant_Constraints
8726 Derived_Def : Boolean := False) return Elist_Id
8728 C : constant Node_Id := Constraint (Def);
8729 Nb_Discr : constant Nat := Number_Discriminants (T);
8731 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8732 -- Saves the expression corresponding to a given discriminant in T
8734 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8735 -- Return the Position number within array Discr_Expr of a discriminant
8736 -- D within the discriminant list of the discriminated type T.
8738 procedure Process_Discriminant_Expression
8741 -- If this is a discriminant constraint on a partial view, do not
8742 -- generate an overflow check on the discriminant expression. The check
8743 -- will be generated when constraining the full view. Otherwise the
8744 -- backend creates duplicate symbols for the temporaries corresponding
8745 -- to the expressions to be checked, causing spurious assembler errors.
8751 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8755 Disc := First_Discriminant (T);
8756 for J in Discr_Expr'Range loop
8761 Next_Discriminant (Disc);
8764 -- Note: Since this function is called on discriminants that are
8765 -- known to belong to the discriminated type, falling through the
8766 -- loop with no match signals an internal compiler error.
8768 raise Program_Error;
8771 -------------------------------------
8772 -- Process_Discriminant_Expression --
8773 -------------------------------------
8775 procedure Process_Discriminant_Expression
8779 BDT : constant Entity_Id := Base_Type (Etype (D));
8782 -- If this is a discriminant constraint on a partial view, do
8783 -- not generate an overflow on the discriminant expression. The
8784 -- check will be generated when constraining the full view.
8786 if Is_Private_Type (T)
8787 and then Present (Full_View (T))
8789 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
8791 Analyze_And_Resolve (Expr, BDT);
8793 end Process_Discriminant_Expression;
8795 -- Declarations local to Build_Discriminant_Constraints
8799 Elist : constant Elist_Id := New_Elmt_List;
8807 Discrim_Present : Boolean := False;
8809 -- Start of processing for Build_Discriminant_Constraints
8812 -- The following loop will process positional associations only.
8813 -- For a positional association, the (single) discriminant is
8814 -- implicitly specified by position, in textual order (RM 3.7.2).
8816 Discr := First_Discriminant (T);
8817 Constr := First (Constraints (C));
8818 for D in Discr_Expr'Range loop
8819 exit when Nkind (Constr) = N_Discriminant_Association;
8822 Error_Msg_N ("too few discriminants given in constraint", C);
8823 return New_Elmt_List;
8825 elsif Nkind (Constr) = N_Range
8826 or else (Nkind (Constr) = N_Attribute_Reference
8828 Attribute_Name (Constr) = Name_Range)
8831 ("a range is not a valid discriminant constraint", Constr);
8832 Discr_Expr (D) := Error;
8835 Process_Discriminant_Expression (Constr, Discr);
8836 Discr_Expr (D) := Constr;
8839 Next_Discriminant (Discr);
8843 if No (Discr) and then Present (Constr) then
8844 Error_Msg_N ("too many discriminants given in constraint", Constr);
8845 return New_Elmt_List;
8848 -- Named associations can be given in any order, but if both positional
8849 -- and named associations are used in the same discriminant constraint,
8850 -- then positional associations must occur first, at their normal
8851 -- position. Hence once a named association is used, the rest of the
8852 -- discriminant constraint must use only named associations.
8854 while Present (Constr) loop
8856 -- Positional association forbidden after a named association
8858 if Nkind (Constr) /= N_Discriminant_Association then
8859 Error_Msg_N ("positional association follows named one", Constr);
8860 return New_Elmt_List;
8862 -- Otherwise it is a named association
8865 -- E records the type of the discriminants in the named
8866 -- association. All the discriminants specified in the same name
8867 -- association must have the same type.
8871 -- Search the list of discriminants in T to see if the simple name
8872 -- given in the constraint matches any of them.
8874 Id := First (Selector_Names (Constr));
8875 while Present (Id) loop
8878 -- If Original_Discriminant is present, we are processing a
8879 -- generic instantiation and this is an instance node. We need
8880 -- to find the name of the corresponding discriminant in the
8881 -- actual record type T and not the name of the discriminant in
8882 -- the generic formal. Example:
8885 -- type G (D : int) is private;
8887 -- subtype W is G (D => 1);
8889 -- type Rec (X : int) is record ... end record;
8890 -- package Q is new P (G => Rec);
8892 -- At the point of the instantiation, formal type G is Rec
8893 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8894 -- which really looks like "subtype W is Rec (D => 1);" at
8895 -- the point of instantiation, we want to find the discriminant
8896 -- that corresponds to D in Rec, i.e. X.
8898 if Present (Original_Discriminant (Id))
8899 and then In_Instance
8901 Discr := Find_Corresponding_Discriminant (Id, T);
8905 Discr := First_Discriminant (T);
8906 while Present (Discr) loop
8907 if Chars (Discr) = Chars (Id) then
8912 Next_Discriminant (Discr);
8916 Error_Msg_N ("& does not match any discriminant", Id);
8917 return New_Elmt_List;
8919 -- If the parent type is a generic formal, preserve the
8920 -- name of the discriminant for subsequent instances.
8921 -- see comment at the beginning of this if statement.
8923 elsif Is_Generic_Type (Root_Type (T)) then
8924 Set_Original_Discriminant (Id, Discr);
8928 Position := Pos_Of_Discr (T, Discr);
8930 if Present (Discr_Expr (Position)) then
8931 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8934 -- Each discriminant specified in the same named association
8935 -- must be associated with a separate copy of the
8936 -- corresponding expression.
8938 if Present (Next (Id)) then
8939 Expr := New_Copy_Tree (Expression (Constr));
8940 Set_Parent (Expr, Parent (Expression (Constr)));
8942 Expr := Expression (Constr);
8945 Discr_Expr (Position) := Expr;
8946 Process_Discriminant_Expression (Expr, Discr);
8949 -- A discriminant association with more than one discriminant
8950 -- name is only allowed if the named discriminants are all of
8951 -- the same type (RM 3.7.1(8)).
8954 E := Base_Type (Etype (Discr));
8956 elsif Base_Type (Etype (Discr)) /= E then
8958 ("all discriminants in an association " &
8959 "must have the same type", Id);
8969 -- A discriminant constraint must provide exactly one value for each
8970 -- discriminant of the type (RM 3.7.1(8)).
8972 for J in Discr_Expr'Range loop
8973 if No (Discr_Expr (J)) then
8974 Error_Msg_N ("too few discriminants given in constraint", C);
8975 return New_Elmt_List;
8979 -- Determine if there are discriminant expressions in the constraint
8981 for J in Discr_Expr'Range loop
8982 if Denotes_Discriminant
8983 (Discr_Expr (J), Check_Concurrent => True)
8985 Discrim_Present := True;
8989 -- Build an element list consisting of the expressions given in the
8990 -- discriminant constraint and apply the appropriate checks. The list
8991 -- is constructed after resolving any named discriminant associations
8992 -- and therefore the expressions appear in the textual order of the
8995 Discr := First_Discriminant (T);
8996 for J in Discr_Expr'Range loop
8997 if Discr_Expr (J) /= Error then
8998 Append_Elmt (Discr_Expr (J), Elist);
9000 -- If any of the discriminant constraints is given by a
9001 -- discriminant and we are in a derived type declaration we
9002 -- have a discriminant renaming. Establish link between new
9003 -- and old discriminant.
9005 if Denotes_Discriminant (Discr_Expr (J)) then
9007 Set_Corresponding_Discriminant
9008 (Entity (Discr_Expr (J)), Discr);
9011 -- Force the evaluation of non-discriminant expressions.
9012 -- If we have found a discriminant in the constraint 3.4(26)
9013 -- and 3.8(18) demand that no range checks are performed are
9014 -- after evaluation. If the constraint is for a component
9015 -- definition that has a per-object constraint, expressions are
9016 -- evaluated but not checked either. In all other cases perform
9020 if Discrim_Present then
9023 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9025 Has_Per_Object_Constraint
9026 (Defining_Identifier (Parent (Parent (Def))))
9030 elsif Is_Access_Type (Etype (Discr)) then
9031 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9034 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9037 Force_Evaluation (Discr_Expr (J));
9040 -- Check that the designated type of an access discriminant's
9041 -- expression is not a class-wide type unless the discriminant's
9042 -- designated type is also class-wide.
9044 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9045 and then not Is_Class_Wide_Type
9046 (Designated_Type (Etype (Discr)))
9047 and then Etype (Discr_Expr (J)) /= Any_Type
9048 and then Is_Class_Wide_Type
9049 (Designated_Type (Etype (Discr_Expr (J))))
9051 Wrong_Type (Discr_Expr (J), Etype (Discr));
9053 elsif Is_Access_Type (Etype (Discr))
9054 and then not Is_Access_Constant (Etype (Discr))
9055 and then Is_Access_Type (Etype (Discr_Expr (J)))
9056 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9059 ("constraint for discriminant& must be access to variable",
9064 Next_Discriminant (Discr);
9068 end Build_Discriminant_Constraints;
9070 ---------------------------------
9071 -- Build_Discriminated_Subtype --
9072 ---------------------------------
9074 procedure Build_Discriminated_Subtype
9078 Related_Nod : Node_Id;
9079 For_Access : Boolean := False)
9081 Has_Discrs : constant Boolean := Has_Discriminants (T);
9082 Constrained : constant Boolean :=
9084 and then not Is_Empty_Elmt_List (Elist)
9085 and then not Is_Class_Wide_Type (T))
9086 or else Is_Constrained (T);
9089 if Ekind (T) = E_Record_Type then
9091 Set_Ekind (Def_Id, E_Private_Subtype);
9092 Set_Is_For_Access_Subtype (Def_Id, True);
9094 Set_Ekind (Def_Id, E_Record_Subtype);
9097 -- Inherit preelaboration flag from base, for types for which it
9098 -- may have been set: records, private types, protected types.
9100 Set_Known_To_Have_Preelab_Init
9101 (Def_Id, Known_To_Have_Preelab_Init (T));
9103 elsif Ekind (T) = E_Task_Type then
9104 Set_Ekind (Def_Id, E_Task_Subtype);
9106 elsif Ekind (T) = E_Protected_Type then
9107 Set_Ekind (Def_Id, E_Protected_Subtype);
9108 Set_Known_To_Have_Preelab_Init
9109 (Def_Id, Known_To_Have_Preelab_Init (T));
9111 elsif Is_Private_Type (T) then
9112 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9113 Set_Known_To_Have_Preelab_Init
9114 (Def_Id, Known_To_Have_Preelab_Init (T));
9116 -- Private subtypes may have private dependents
9118 Set_Private_Dependents (Def_Id, New_Elmt_List);
9120 elsif Is_Class_Wide_Type (T) then
9121 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9124 -- Incomplete type. Attach subtype to list of dependents, to be
9125 -- completed with full view of parent type, unless is it the
9126 -- designated subtype of a record component within an init_proc.
9127 -- This last case arises for a component of an access type whose
9128 -- designated type is incomplete (e.g. a Taft Amendment type).
9129 -- The designated subtype is within an inner scope, and needs no
9130 -- elaboration, because only the access type is needed in the
9131 -- initialization procedure.
9133 Set_Ekind (Def_Id, Ekind (T));
9135 if For_Access and then Within_Init_Proc then
9138 Append_Elmt (Def_Id, Private_Dependents (T));
9142 Set_Etype (Def_Id, T);
9143 Init_Size_Align (Def_Id);
9144 Set_Has_Discriminants (Def_Id, Has_Discrs);
9145 Set_Is_Constrained (Def_Id, Constrained);
9147 Set_First_Entity (Def_Id, First_Entity (T));
9148 Set_Last_Entity (Def_Id, Last_Entity (T));
9149 Set_Has_Implicit_Dereference
9150 (Def_Id, Has_Implicit_Dereference (T));
9152 -- If the subtype is the completion of a private declaration, there may
9153 -- have been representation clauses for the partial view, and they must
9154 -- be preserved. Build_Derived_Type chains the inherited clauses with
9155 -- the ones appearing on the extension. If this comes from a subtype
9156 -- declaration, all clauses are inherited.
9158 if No (First_Rep_Item (Def_Id)) then
9159 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9162 if Is_Tagged_Type (T) then
9163 Set_Is_Tagged_Type (Def_Id);
9164 Make_Class_Wide_Type (Def_Id);
9167 Set_Stored_Constraint (Def_Id, No_Elist);
9170 Set_Discriminant_Constraint (Def_Id, Elist);
9171 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9174 if Is_Tagged_Type (T) then
9176 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9177 -- concurrent record type (which has the list of primitive
9180 if Ada_Version >= Ada_2005
9181 and then Is_Concurrent_Type (T)
9183 Set_Corresponding_Record_Type (Def_Id,
9184 Corresponding_Record_Type (T));
9186 Set_Direct_Primitive_Operations (Def_Id,
9187 Direct_Primitive_Operations (T));
9190 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9193 -- Subtypes introduced by component declarations do not need to be
9194 -- marked as delayed, and do not get freeze nodes, because the semantics
9195 -- verifies that the parents of the subtypes are frozen before the
9196 -- enclosing record is frozen.
9198 if not Is_Type (Scope (Def_Id)) then
9199 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9201 if Is_Private_Type (T)
9202 and then Present (Full_View (T))
9204 Conditional_Delay (Def_Id, Full_View (T));
9206 Conditional_Delay (Def_Id, T);
9210 if Is_Record_Type (T) then
9211 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9214 and then not Is_Empty_Elmt_List (Elist)
9215 and then not For_Access
9217 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9218 elsif not For_Access then
9219 Set_Cloned_Subtype (Def_Id, T);
9222 end Build_Discriminated_Subtype;
9224 ---------------------------
9225 -- Build_Itype_Reference --
9226 ---------------------------
9228 procedure Build_Itype_Reference
9232 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9235 -- Itype references are only created for use by the back-end
9237 if Inside_A_Generic then
9240 Set_Itype (IR, Ityp);
9241 Insert_After (Nod, IR);
9243 end Build_Itype_Reference;
9245 ------------------------
9246 -- Build_Scalar_Bound --
9247 ------------------------
9249 function Build_Scalar_Bound
9252 Der_T : Entity_Id) return Node_Id
9254 New_Bound : Entity_Id;
9257 -- Note: not clear why this is needed, how can the original bound
9258 -- be unanalyzed at this point? and if it is, what business do we
9259 -- have messing around with it? and why is the base type of the
9260 -- parent type the right type for the resolution. It probably is
9261 -- not. It is OK for the new bound we are creating, but not for
9262 -- the old one??? Still if it never happens, no problem.
9264 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9266 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9267 New_Bound := New_Copy (Bound);
9268 Set_Etype (New_Bound, Der_T);
9269 Set_Analyzed (New_Bound);
9271 elsif Is_Entity_Name (Bound) then
9272 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9274 -- The following is almost certainly wrong. What business do we have
9275 -- relocating a node (Bound) that is presumably still attached to
9276 -- the tree elsewhere???
9279 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9282 Set_Etype (New_Bound, Der_T);
9284 end Build_Scalar_Bound;
9286 --------------------------------
9287 -- Build_Underlying_Full_View --
9288 --------------------------------
9290 procedure Build_Underlying_Full_View
9295 Loc : constant Source_Ptr := Sloc (N);
9296 Subt : constant Entity_Id :=
9297 Make_Defining_Identifier
9298 (Loc, New_External_Name (Chars (Typ), 'S'));
9305 procedure Set_Discriminant_Name (Id : Node_Id);
9306 -- If the derived type has discriminants, they may rename discriminants
9307 -- of the parent. When building the full view of the parent, we need to
9308 -- recover the names of the original discriminants if the constraint is
9309 -- given by named associations.
9311 ---------------------------
9312 -- Set_Discriminant_Name --
9313 ---------------------------
9315 procedure Set_Discriminant_Name (Id : Node_Id) is
9319 Set_Original_Discriminant (Id, Empty);
9321 if Has_Discriminants (Typ) then
9322 Disc := First_Discriminant (Typ);
9323 while Present (Disc) loop
9324 if Chars (Disc) = Chars (Id)
9325 and then Present (Corresponding_Discriminant (Disc))
9327 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9329 Next_Discriminant (Disc);
9332 end Set_Discriminant_Name;
9334 -- Start of processing for Build_Underlying_Full_View
9337 if Nkind (N) = N_Full_Type_Declaration then
9338 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9340 elsif Nkind (N) = N_Subtype_Declaration then
9341 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9343 elsif Nkind (N) = N_Component_Declaration then
9346 (Constraint (Subtype_Indication (Component_Definition (N))));
9349 raise Program_Error;
9352 C := First (Constraints (Constr));
9353 while Present (C) loop
9354 if Nkind (C) = N_Discriminant_Association then
9355 Id := First (Selector_Names (C));
9356 while Present (Id) loop
9357 Set_Discriminant_Name (Id);
9366 Make_Subtype_Declaration (Loc,
9367 Defining_Identifier => Subt,
9368 Subtype_Indication =>
9369 Make_Subtype_Indication (Loc,
9370 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9371 Constraint => New_Copy_Tree (Constr)));
9373 -- If this is a component subtype for an outer itype, it is not
9374 -- a list member, so simply set the parent link for analysis: if
9375 -- the enclosing type does not need to be in a declarative list,
9376 -- neither do the components.
9378 if Is_List_Member (N)
9379 and then Nkind (N) /= N_Component_Declaration
9381 Insert_Before (N, Indic);
9383 Set_Parent (Indic, Parent (N));
9387 Set_Underlying_Full_View (Typ, Full_View (Subt));
9388 end Build_Underlying_Full_View;
9390 -------------------------------
9391 -- Check_Abstract_Overriding --
9392 -------------------------------
9394 procedure Check_Abstract_Overriding (T : Entity_Id) is
9395 Alias_Subp : Entity_Id;
9401 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9402 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9403 -- which has pragma Implemented already set. Check whether Subp's entity
9404 -- kind conforms to the implementation kind of the overridden routine.
9406 procedure Check_Pragma_Implemented
9408 Iface_Subp : Entity_Id);
9409 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9410 -- Iface_Subp and both entities have pragma Implemented already set on
9411 -- them. Check whether the two implementation kinds are conforming.
9413 procedure Inherit_Pragma_Implemented
9415 Iface_Subp : Entity_Id);
9416 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9417 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9418 -- Propagate the implementation kind of Iface_Subp to Subp.
9420 ------------------------------
9421 -- Check_Pragma_Implemented --
9422 ------------------------------
9424 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9425 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9426 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9427 Subp_Alias : constant Entity_Id := Alias (Subp);
9428 Contr_Typ : Entity_Id;
9429 Impl_Subp : Entity_Id;
9432 -- Subp must have an alias since it is a hidden entity used to link
9433 -- an interface subprogram to its overriding counterpart.
9435 pragma Assert (Present (Subp_Alias));
9437 -- Handle aliases to synchronized wrappers
9439 Impl_Subp := Subp_Alias;
9441 if Is_Primitive_Wrapper (Impl_Subp) then
9442 Impl_Subp := Wrapped_Entity (Impl_Subp);
9445 -- Extract the type of the controlling formal
9447 Contr_Typ := Etype (First_Formal (Subp_Alias));
9449 if Is_Concurrent_Record_Type (Contr_Typ) then
9450 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9453 -- An interface subprogram whose implementation kind is By_Entry must
9454 -- be implemented by an entry.
9456 if Impl_Kind = Name_By_Entry
9457 and then Ekind (Impl_Subp) /= E_Entry
9459 Error_Msg_Node_2 := Iface_Alias;
9461 ("type & must implement abstract subprogram & with an entry",
9462 Subp_Alias, Contr_Typ);
9464 elsif Impl_Kind = Name_By_Protected_Procedure then
9466 -- An interface subprogram whose implementation kind is By_
9467 -- Protected_Procedure cannot be implemented by a primitive
9468 -- procedure of a task type.
9470 if Ekind (Contr_Typ) /= E_Protected_Type then
9471 Error_Msg_Node_2 := Contr_Typ;
9473 ("interface subprogram & cannot be implemented by a " &
9474 "primitive procedure of task type &", Subp_Alias,
9477 -- An interface subprogram whose implementation kind is By_
9478 -- Protected_Procedure must be implemented by a procedure.
9480 elsif Ekind (Impl_Subp) /= E_Procedure then
9481 Error_Msg_Node_2 := Iface_Alias;
9483 ("type & must implement abstract subprogram & with a " &
9484 "procedure", Subp_Alias, Contr_Typ);
9486 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9487 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9489 Error_Msg_Name_1 := Impl_Kind;
9491 ("overriding operation& must have synchronization%",
9495 -- If primitive has Optional synchronization, overriding operation
9496 -- must match if it has an explicit synchronization..
9498 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9499 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9501 Error_Msg_Name_1 := Impl_Kind;
9503 ("overriding operation& must have syncrhonization%",
9506 end Check_Pragma_Implemented;
9508 ------------------------------
9509 -- Check_Pragma_Implemented --
9510 ------------------------------
9512 procedure Check_Pragma_Implemented
9514 Iface_Subp : Entity_Id)
9516 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9517 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9520 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9521 -- and overriding subprogram are different. In general this is an
9522 -- error except when the implementation kind of the overridden
9523 -- subprograms is By_Any or Optional.
9525 if Iface_Kind /= Subp_Kind
9526 and then Iface_Kind /= Name_By_Any
9527 and then Iface_Kind /= Name_Optional
9529 if Iface_Kind = Name_By_Entry then
9531 ("incompatible implementation kind, overridden subprogram " &
9532 "is marked By_Entry", Subp);
9535 ("incompatible implementation kind, overridden subprogram " &
9536 "is marked By_Protected_Procedure", Subp);
9539 end Check_Pragma_Implemented;
9541 --------------------------------
9542 -- Inherit_Pragma_Implemented --
9543 --------------------------------
9545 procedure Inherit_Pragma_Implemented
9547 Iface_Subp : Entity_Id)
9549 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9550 Loc : constant Source_Ptr := Sloc (Subp);
9551 Impl_Prag : Node_Id;
9554 -- Since the implementation kind is stored as a representation item
9555 -- rather than a flag, create a pragma node.
9559 Chars => Name_Implemented,
9560 Pragma_Argument_Associations => New_List (
9561 Make_Pragma_Argument_Association (Loc,
9562 Expression => New_Occurrence_Of (Subp, Loc)),
9564 Make_Pragma_Argument_Association (Loc,
9565 Expression => Make_Identifier (Loc, Iface_Kind))));
9567 -- The pragma doesn't need to be analyzed because it is internally
9568 -- built. It is safe to directly register it as a rep item since we
9569 -- are only interested in the characters of the implementation kind.
9571 Record_Rep_Item (Subp, Impl_Prag);
9572 end Inherit_Pragma_Implemented;
9574 -- Start of processing for Check_Abstract_Overriding
9577 Op_List := Primitive_Operations (T);
9579 -- Loop to check primitive operations
9581 Elmt := First_Elmt (Op_List);
9582 while Present (Elmt) loop
9583 Subp := Node (Elmt);
9584 Alias_Subp := Alias (Subp);
9586 -- Inherited subprograms are identified by the fact that they do not
9587 -- come from source, and the associated source location is the
9588 -- location of the first subtype of the derived type.
9590 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9591 -- subprograms that "require overriding".
9593 -- Special exception, do not complain about failure to override the
9594 -- stream routines _Input and _Output, as well as the primitive
9595 -- operations used in dispatching selects since we always provide
9596 -- automatic overridings for these subprograms.
9598 -- Also ignore this rule for convention CIL since .NET libraries
9599 -- do bizarre things with interfaces???
9601 -- The partial view of T may have been a private extension, for
9602 -- which inherited functions dispatching on result are abstract.
9603 -- If the full view is a null extension, there is no need for
9604 -- overriding in Ada 2005, but wrappers need to be built for them
9605 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9607 if Is_Null_Extension (T)
9608 and then Has_Controlling_Result (Subp)
9609 and then Ada_Version >= Ada_2005
9610 and then Present (Alias_Subp)
9611 and then not Comes_From_Source (Subp)
9612 and then not Is_Abstract_Subprogram (Alias_Subp)
9613 and then not Is_Access_Type (Etype (Subp))
9617 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9618 -- processing because this check is done with the aliased
9621 elsif Present (Interface_Alias (Subp)) then
9624 elsif (Is_Abstract_Subprogram (Subp)
9625 or else Requires_Overriding (Subp)
9627 (Has_Controlling_Result (Subp)
9628 and then Present (Alias_Subp)
9629 and then not Comes_From_Source (Subp)
9630 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9631 and then not Is_TSS (Subp, TSS_Stream_Input)
9632 and then not Is_TSS (Subp, TSS_Stream_Output)
9633 and then not Is_Abstract_Type (T)
9634 and then Convention (T) /= Convention_CIL
9635 and then not Is_Predefined_Interface_Primitive (Subp)
9637 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9638 -- with abstract interface types because the check will be done
9639 -- with the aliased entity (otherwise we generate a duplicated
9642 and then not Present (Interface_Alias (Subp))
9644 if Present (Alias_Subp) then
9646 -- Only perform the check for a derived subprogram when the
9647 -- type has an explicit record extension. This avoids incorrect
9648 -- flagging of abstract subprograms for the case of a type
9649 -- without an extension that is derived from a formal type
9650 -- with a tagged actual (can occur within a private part).
9652 -- Ada 2005 (AI-391): In the case of an inherited function with
9653 -- a controlling result of the type, the rule does not apply if
9654 -- the type is a null extension (unless the parent function
9655 -- itself is abstract, in which case the function must still be
9656 -- be overridden). The expander will generate an overriding
9657 -- wrapper function calling the parent subprogram (see
9658 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9660 Type_Def := Type_Definition (Parent (T));
9662 if Nkind (Type_Def) = N_Derived_Type_Definition
9663 and then Present (Record_Extension_Part (Type_Def))
9665 (Ada_Version < Ada_2005
9666 or else not Is_Null_Extension (T)
9667 or else Ekind (Subp) = E_Procedure
9668 or else not Has_Controlling_Result (Subp)
9669 or else Is_Abstract_Subprogram (Alias_Subp)
9670 or else Requires_Overriding (Subp)
9671 or else Is_Access_Type (Etype (Subp)))
9673 -- Avoid reporting error in case of abstract predefined
9674 -- primitive inherited from interface type because the
9675 -- body of internally generated predefined primitives
9676 -- of tagged types are generated later by Freeze_Type
9678 if Is_Interface (Root_Type (T))
9679 and then Is_Abstract_Subprogram (Subp)
9680 and then Is_Predefined_Dispatching_Operation (Subp)
9681 and then not Comes_From_Source (Ultimate_Alias (Subp))
9687 ("type must be declared abstract or & overridden",
9690 -- Traverse the whole chain of aliased subprograms to
9691 -- complete the error notification. This is especially
9692 -- useful for traceability of the chain of entities when
9693 -- the subprogram corresponds with an interface
9694 -- subprogram (which may be defined in another package).
9696 if Present (Alias_Subp) then
9702 while Present (Alias (E)) loop
9704 -- Avoid reporting redundant errors on entities
9705 -- inherited from interfaces
9707 if Sloc (E) /= Sloc (T) then
9708 Error_Msg_Sloc := Sloc (E);
9710 ("\& has been inherited #", T, Subp);
9716 Error_Msg_Sloc := Sloc (E);
9718 -- AI05-0068: report if there is an overriding
9719 -- non-abstract subprogram that is invisible.
9722 and then not Is_Abstract_Subprogram (E)
9725 ("\& subprogram# is not visible",
9730 ("\& has been inherited from subprogram #",
9737 -- Ada 2005 (AI-345): Protected or task type implementing
9738 -- abstract interfaces.
9740 elsif Is_Concurrent_Record_Type (T)
9741 and then Present (Interfaces (T))
9743 -- If an inherited subprogram is implemented by a protected
9744 -- procedure or an entry, then the first parameter of the
9745 -- inherited subprogram shall be of mode OUT or IN OUT, or
9746 -- an access-to-variable parameter (RM 9.4(11.9/3))
9748 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
9749 and then Ekind (First_Formal (Subp)) = E_In_Parameter
9750 and then Ekind (Subp) /= E_Function
9751 and then not Is_Predefined_Dispatching_Operation (Subp)
9753 Error_Msg_PT (T, Subp);
9755 -- Some other kind of overriding failure
9759 ("interface subprogram & must be overridden",
9762 -- Examine primitive operations of synchronized type,
9763 -- to find homonyms that have the wrong profile.
9770 First_Entity (Corresponding_Concurrent_Type (T));
9771 while Present (Prim) loop
9772 if Chars (Prim) = Chars (Subp) then
9774 ("profile is not type conformant with "
9775 & "prefixed view profile of "
9776 & "inherited operation&", Prim, Subp);
9786 Error_Msg_Node_2 := T;
9788 ("abstract subprogram& not allowed for type&", Subp);
9790 -- Also post unconditional warning on the type (unconditional
9791 -- so that if there are more than one of these cases, we get
9792 -- them all, and not just the first one).
9794 Error_Msg_Node_2 := Subp;
9795 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9799 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
9801 -- Subp is an expander-generated procedure which maps an interface
9802 -- alias to a protected wrapper. The interface alias is flagged by
9803 -- pragma Implemented. Ensure that Subp is a procedure when the
9804 -- implementation kind is By_Protected_Procedure or an entry when
9807 if Ada_Version >= Ada_2012
9808 and then Is_Hidden (Subp)
9809 and then Present (Interface_Alias (Subp))
9810 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9812 Check_Pragma_Implemented (Subp);
9815 -- Subp is an interface primitive which overrides another interface
9816 -- primitive marked with pragma Implemented.
9818 if Ada_Version >= Ada_2012
9819 and then Present (Overridden_Operation (Subp))
9820 and then Has_Rep_Pragma
9821 (Overridden_Operation (Subp), Name_Implemented)
9823 -- If the overriding routine is also marked by Implemented, check
9824 -- that the two implementation kinds are conforming.
9826 if Has_Rep_Pragma (Subp, Name_Implemented) then
9827 Check_Pragma_Implemented
9829 Iface_Subp => Overridden_Operation (Subp));
9831 -- Otherwise the overriding routine inherits the implementation
9832 -- kind from the overridden subprogram.
9835 Inherit_Pragma_Implemented
9837 Iface_Subp => Overridden_Operation (Subp));
9841 -- If the operation is a wrapper for a synchronized primitive, it
9842 -- may be called indirectly through a dispatching select. We assume
9843 -- that it will be referenced elsewhere indirectly, and suppress
9844 -- warnings about an unused entity.
9846 if Is_Primitive_Wrapper (Subp)
9847 and then Present (Wrapped_Entity (Subp))
9849 Set_Referenced (Wrapped_Entity (Subp));
9854 end Check_Abstract_Overriding;
9856 ------------------------------------------------
9857 -- Check_Access_Discriminant_Requires_Limited --
9858 ------------------------------------------------
9860 procedure Check_Access_Discriminant_Requires_Limited
9865 -- A discriminant_specification for an access discriminant shall appear
9866 -- only in the declaration for a task or protected type, or for a type
9867 -- with the reserved word 'limited' in its definition or in one of its
9868 -- ancestors (RM 3.7(10)).
9870 -- AI-0063: The proper condition is that type must be immutably limited,
9871 -- or else be a partial view.
9873 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9874 if Is_Limited_View (Current_Scope)
9876 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9877 and then Limited_Present (Parent (Current_Scope)))
9883 ("access discriminants allowed only for limited types", Loc);
9886 end Check_Access_Discriminant_Requires_Limited;
9888 -----------------------------------
9889 -- Check_Aliased_Component_Types --
9890 -----------------------------------
9892 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9896 -- ??? Also need to check components of record extensions, but not
9897 -- components of protected types (which are always limited).
9899 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9900 -- types to be unconstrained. This is safe because it is illegal to
9901 -- create access subtypes to such types with explicit discriminant
9904 if not Is_Limited_Type (T) then
9905 if Ekind (T) = E_Record_Type then
9906 C := First_Component (T);
9907 while Present (C) loop
9909 and then Has_Discriminants (Etype (C))
9910 and then not Is_Constrained (Etype (C))
9911 and then not In_Instance_Body
9912 and then Ada_Version < Ada_2005
9915 ("aliased component must be constrained (RM 3.6(11))",
9922 elsif Ekind (T) = E_Array_Type then
9923 if Has_Aliased_Components (T)
9924 and then Has_Discriminants (Component_Type (T))
9925 and then not Is_Constrained (Component_Type (T))
9926 and then not In_Instance_Body
9927 and then Ada_Version < Ada_2005
9930 ("aliased component type must be constrained (RM 3.6(11))",
9935 end Check_Aliased_Component_Types;
9937 ----------------------
9938 -- Check_Completion --
9939 ----------------------
9941 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9944 procedure Post_Error;
9945 -- Post error message for lack of completion for entity E
9951 procedure Post_Error is
9953 procedure Missing_Body;
9954 -- Output missing body message
9960 procedure Missing_Body is
9962 -- Spec is in same unit, so we can post on spec
9964 if In_Same_Source_Unit (Body_Id, E) then
9965 Error_Msg_N ("missing body for &", E);
9967 -- Spec is in a separate unit, so we have to post on the body
9970 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9974 -- Start of processing for Post_Error
9977 if not Comes_From_Source (E) then
9979 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9980 -- It may be an anonymous protected type created for a
9981 -- single variable. Post error on variable, if present.
9987 Var := First_Entity (Current_Scope);
9988 while Present (Var) loop
9989 exit when Etype (Var) = E
9990 and then Comes_From_Source (Var);
9995 if Present (Var) then
10002 -- If a generated entity has no completion, then either previous
10003 -- semantic errors have disabled the expansion phase, or else we had
10004 -- missing subunits, or else we are compiling without expansion,
10005 -- or else something is very wrong.
10007 if not Comes_From_Source (E) then
10009 (Serious_Errors_Detected > 0
10010 or else Configurable_Run_Time_Violations > 0
10011 or else Subunits_Missing
10012 or else not Expander_Active);
10015 -- Here for source entity
10018 -- Here if no body to post the error message, so we post the error
10019 -- on the declaration that has no completion. This is not really
10020 -- the right place to post it, think about this later ???
10022 if No (Body_Id) then
10023 if Is_Type (E) then
10025 ("missing full declaration for }", Parent (E), E);
10027 Error_Msg_NE ("missing body for &", Parent (E), E);
10030 -- Package body has no completion for a declaration that appears
10031 -- in the corresponding spec. Post error on the body, with a
10032 -- reference to the non-completed declaration.
10035 Error_Msg_Sloc := Sloc (E);
10037 if Is_Type (E) then
10038 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10040 elsif Is_Overloadable (E)
10041 and then Current_Entity_In_Scope (E) /= E
10043 -- It may be that the completion is mistyped and appears as
10044 -- a distinct overloading of the entity.
10047 Candidate : constant Entity_Id :=
10048 Current_Entity_In_Scope (E);
10049 Decl : constant Node_Id :=
10050 Unit_Declaration_Node (Candidate);
10053 if Is_Overloadable (Candidate)
10054 and then Ekind (Candidate) = Ekind (E)
10055 and then Nkind (Decl) = N_Subprogram_Body
10056 and then Acts_As_Spec (Decl)
10058 Check_Type_Conformant (Candidate, E);
10072 -- Start of processing for Check_Completion
10075 E := First_Entity (Current_Scope);
10076 while Present (E) loop
10077 if Is_Intrinsic_Subprogram (E) then
10080 -- The following situation requires special handling: a child unit
10081 -- that appears in the context clause of the body of its parent:
10083 -- procedure Parent.Child (...);
10085 -- with Parent.Child;
10086 -- package body Parent is
10088 -- Here Parent.Child appears as a local entity, but should not be
10089 -- flagged as requiring completion, because it is a compilation
10092 -- Ignore missing completion for a subprogram that does not come from
10093 -- source (including the _Call primitive operation of RAS types,
10094 -- which has to have the flag Comes_From_Source for other purposes):
10095 -- we assume that the expander will provide the missing completion.
10096 -- In case of previous errors, other expansion actions that provide
10097 -- bodies for null procedures with not be invoked, so inhibit message
10100 -- Note that E_Operator is not in the list that follows, because
10101 -- this kind is reserved for predefined operators, that are
10102 -- intrinsic and do not need completion.
10104 elsif Ekind (E) = E_Function
10105 or else Ekind (E) = E_Procedure
10106 or else Ekind (E) = E_Generic_Function
10107 or else Ekind (E) = E_Generic_Procedure
10109 if Has_Completion (E) then
10112 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10115 elsif Is_Subprogram (E)
10116 and then (not Comes_From_Source (E)
10117 or else Chars (E) = Name_uCall)
10122 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10126 elsif Nkind (Parent (E)) = N_Procedure_Specification
10127 and then Null_Present (Parent (E))
10128 and then Serious_Errors_Detected > 0
10136 elsif Is_Entry (E) then
10137 if not Has_Completion (E) and then
10138 (Ekind (Scope (E)) = E_Protected_Object
10139 or else Ekind (Scope (E)) = E_Protected_Type)
10144 elsif Is_Package_Or_Generic_Package (E) then
10145 if Unit_Requires_Body (E) then
10146 if not Has_Completion (E)
10147 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10153 elsif not Is_Child_Unit (E) then
10154 May_Need_Implicit_Body (E);
10157 -- A formal incomplete type (Ada 2012) does not require a completion;
10158 -- other incomplete type declarations do.
10160 elsif Ekind (E) = E_Incomplete_Type
10161 and then No (Underlying_Type (E))
10162 and then not Is_Generic_Type (E)
10166 elsif (Ekind (E) = E_Task_Type or else
10167 Ekind (E) = E_Protected_Type)
10168 and then not Has_Completion (E)
10172 -- A single task declared in the current scope is a constant, verify
10173 -- that the body of its anonymous type is in the same scope. If the
10174 -- task is defined elsewhere, this may be a renaming declaration for
10175 -- which no completion is needed.
10177 elsif Ekind (E) = E_Constant
10178 and then Ekind (Etype (E)) = E_Task_Type
10179 and then not Has_Completion (Etype (E))
10180 and then Scope (Etype (E)) = Current_Scope
10184 elsif Ekind (E) = E_Protected_Object
10185 and then not Has_Completion (Etype (E))
10189 elsif Ekind (E) = E_Record_Type then
10190 if Is_Tagged_Type (E) then
10191 Check_Abstract_Overriding (E);
10192 Check_Conventions (E);
10195 Check_Aliased_Component_Types (E);
10197 elsif Ekind (E) = E_Array_Type then
10198 Check_Aliased_Component_Types (E);
10204 end Check_Completion;
10206 ------------------------------------
10207 -- Check_CPP_Type_Has_No_Defaults --
10208 ------------------------------------
10210 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10211 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10216 -- Obtain the component list
10218 if Nkind (Tdef) = N_Record_Definition then
10219 Clist := Component_List (Tdef);
10220 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10221 Clist := Component_List (Record_Extension_Part (Tdef));
10224 -- Check all components to ensure no default expressions
10226 if Present (Clist) then
10227 Comp := First (Component_Items (Clist));
10228 while Present (Comp) loop
10229 if Present (Expression (Comp)) then
10231 ("component of imported 'C'P'P type cannot have "
10232 & "default expression", Expression (Comp));
10238 end Check_CPP_Type_Has_No_Defaults;
10240 ----------------------------
10241 -- Check_Delta_Expression --
10242 ----------------------------
10244 procedure Check_Delta_Expression (E : Node_Id) is
10246 if not (Is_Real_Type (Etype (E))) then
10247 Wrong_Type (E, Any_Real);
10249 elsif not Is_OK_Static_Expression (E) then
10250 Flag_Non_Static_Expr
10251 ("non-static expression used for delta value!", E);
10253 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10254 Error_Msg_N ("delta expression must be positive", E);
10260 -- If any of above errors occurred, then replace the incorrect
10261 -- expression by the real 0.1, which should prevent further errors.
10264 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10265 Analyze_And_Resolve (E, Standard_Float);
10266 end Check_Delta_Expression;
10268 -----------------------------
10269 -- Check_Digits_Expression --
10270 -----------------------------
10272 procedure Check_Digits_Expression (E : Node_Id) is
10274 if not (Is_Integer_Type (Etype (E))) then
10275 Wrong_Type (E, Any_Integer);
10277 elsif not Is_OK_Static_Expression (E) then
10278 Flag_Non_Static_Expr
10279 ("non-static expression used for digits value!", E);
10281 elsif Expr_Value (E) <= 0 then
10282 Error_Msg_N ("digits value must be greater than zero", E);
10288 -- If any of above errors occurred, then replace the incorrect
10289 -- expression by the integer 1, which should prevent further errors.
10291 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
10292 Analyze_And_Resolve (E, Standard_Integer);
10294 end Check_Digits_Expression;
10296 --------------------------
10297 -- Check_Initialization --
10298 --------------------------
10300 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
10302 if Is_Limited_Type (T)
10303 and then not In_Instance
10304 and then not In_Inlined_Body
10306 if not OK_For_Limited_Init (T, Exp) then
10308 -- In GNAT mode, this is just a warning, to allow it to be evilly
10309 -- turned off. Otherwise it is a real error.
10313 ("??cannot initialize entities of limited type!", Exp);
10315 elsif Ada_Version < Ada_2005 then
10317 -- The side effect removal machinery may generate illegal Ada
10318 -- code to avoid the usage of access types and 'reference in
10319 -- SPARK mode. Since this is legal code with respect to theorem
10320 -- proving, do not emit the error.
10323 and then Nkind (Exp) = N_Function_Call
10324 and then Nkind (Parent (Exp)) = N_Object_Declaration
10325 and then not Comes_From_Source
10326 (Defining_Identifier (Parent (Exp)))
10332 ("cannot initialize entities of limited type", Exp);
10333 Explain_Limited_Type (T, Exp);
10337 -- Specialize error message according to kind of illegal
10338 -- initial expression.
10340 if Nkind (Exp) = N_Type_Conversion
10341 and then Nkind (Expression (Exp)) = N_Function_Call
10344 ("illegal context for call"
10345 & " to function with limited result", Exp);
10349 ("initialization of limited object requires aggregate "
10350 & "or function call", Exp);
10355 end Check_Initialization;
10357 ----------------------
10358 -- Check_Interfaces --
10359 ----------------------
10361 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
10362 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
10365 Iface_Def : Node_Id;
10366 Iface_Typ : Entity_Id;
10367 Parent_Node : Node_Id;
10369 Is_Task : Boolean := False;
10370 -- Set True if parent type or any progenitor is a task interface
10372 Is_Protected : Boolean := False;
10373 -- Set True if parent type or any progenitor is a protected interface
10375 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
10376 -- Check that a progenitor is compatible with declaration.
10377 -- Error is posted on Error_Node.
10383 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
10384 Iface_Id : constant Entity_Id :=
10385 Defining_Identifier (Parent (Iface_Def));
10386 Type_Def : Node_Id;
10389 if Nkind (N) = N_Private_Extension_Declaration then
10392 Type_Def := Type_Definition (N);
10395 if Is_Task_Interface (Iface_Id) then
10398 elsif Is_Protected_Interface (Iface_Id) then
10399 Is_Protected := True;
10402 if Is_Synchronized_Interface (Iface_Id) then
10404 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
10405 -- extension derived from a synchronized interface must explicitly
10406 -- be declared synchronized, because the full view will be a
10407 -- synchronized type.
10409 if Nkind (N) = N_Private_Extension_Declaration then
10410 if not Synchronized_Present (N) then
10412 ("private extension of& must be explicitly synchronized",
10416 -- However, by 3.9.4(16/2), a full type that is a record extension
10417 -- is never allowed to derive from a synchronized interface (note
10418 -- that interfaces must be excluded from this check, because those
10419 -- are represented by derived type definitions in some cases).
10421 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10422 and then not Interface_Present (Type_Definition (N))
10424 Error_Msg_N ("record extension cannot derive from synchronized"
10425 & " interface", Error_Node);
10429 -- Check that the characteristics of the progenitor are compatible
10430 -- with the explicit qualifier in the declaration.
10431 -- The check only applies to qualifiers that come from source.
10432 -- Limited_Present also appears in the declaration of corresponding
10433 -- records, and the check does not apply to them.
10435 if Limited_Present (Type_Def)
10437 Is_Concurrent_Record_Type (Defining_Identifier (N))
10439 if Is_Limited_Interface (Parent_Type)
10440 and then not Is_Limited_Interface (Iface_Id)
10443 ("progenitor& must be limited interface",
10444 Error_Node, Iface_Id);
10447 (Task_Present (Iface_Def)
10448 or else Protected_Present (Iface_Def)
10449 or else Synchronized_Present (Iface_Def))
10450 and then Nkind (N) /= N_Private_Extension_Declaration
10451 and then not Error_Posted (N)
10454 ("progenitor& must be limited interface",
10455 Error_Node, Iface_Id);
10458 -- Protected interfaces can only inherit from limited, synchronized
10459 -- or protected interfaces.
10461 elsif Nkind (N) = N_Full_Type_Declaration
10462 and then Protected_Present (Type_Def)
10464 if Limited_Present (Iface_Def)
10465 or else Synchronized_Present (Iface_Def)
10466 or else Protected_Present (Iface_Def)
10470 elsif Task_Present (Iface_Def) then
10471 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10472 & " from task interface", Error_Node);
10475 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10476 & " from non-limited interface", Error_Node);
10479 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
10480 -- limited and synchronized.
10482 elsif Synchronized_Present (Type_Def) then
10483 if Limited_Present (Iface_Def)
10484 or else Synchronized_Present (Iface_Def)
10488 elsif Protected_Present (Iface_Def)
10489 and then Nkind (N) /= N_Private_Extension_Declaration
10491 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10492 & " from protected interface", Error_Node);
10494 elsif Task_Present (Iface_Def)
10495 and then Nkind (N) /= N_Private_Extension_Declaration
10497 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10498 & " from task interface", Error_Node);
10500 elsif not Is_Limited_Interface (Iface_Id) then
10501 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10502 & " from non-limited interface", Error_Node);
10505 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
10506 -- synchronized or task interfaces.
10508 elsif Nkind (N) = N_Full_Type_Declaration
10509 and then Task_Present (Type_Def)
10511 if Limited_Present (Iface_Def)
10512 or else Synchronized_Present (Iface_Def)
10513 or else Task_Present (Iface_Def)
10517 elsif Protected_Present (Iface_Def) then
10518 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10519 & " protected interface", Error_Node);
10522 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10523 & " non-limited interface", Error_Node);
10528 -- Start of processing for Check_Interfaces
10531 if Is_Interface (Parent_Type) then
10532 if Is_Task_Interface (Parent_Type) then
10535 elsif Is_Protected_Interface (Parent_Type) then
10536 Is_Protected := True;
10540 if Nkind (N) = N_Private_Extension_Declaration then
10542 -- Check that progenitors are compatible with declaration
10544 Iface := First (Interface_List (Def));
10545 while Present (Iface) loop
10546 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10548 Parent_Node := Parent (Base_Type (Iface_Typ));
10549 Iface_Def := Type_Definition (Parent_Node);
10551 if not Is_Interface (Iface_Typ) then
10552 Diagnose_Interface (Iface, Iface_Typ);
10555 Check_Ifaces (Iface_Def, Iface);
10561 if Is_Task and Is_Protected then
10563 ("type cannot derive from task and protected interface", N);
10569 -- Full type declaration of derived type.
10570 -- Check compatibility with parent if it is interface type
10572 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10573 and then Is_Interface (Parent_Type)
10575 Parent_Node := Parent (Parent_Type);
10577 -- More detailed checks for interface varieties
10580 (Iface_Def => Type_Definition (Parent_Node),
10581 Error_Node => Subtype_Indication (Type_Definition (N)));
10584 Iface := First (Interface_List (Def));
10585 while Present (Iface) loop
10586 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10588 Parent_Node := Parent (Base_Type (Iface_Typ));
10589 Iface_Def := Type_Definition (Parent_Node);
10591 if not Is_Interface (Iface_Typ) then
10592 Diagnose_Interface (Iface, Iface_Typ);
10595 -- "The declaration of a specific descendant of an interface
10596 -- type freezes the interface type" RM 13.14
10598 Freeze_Before (N, Iface_Typ);
10599 Check_Ifaces (Iface_Def, Error_Node => Iface);
10605 if Is_Task and Is_Protected then
10607 ("type cannot derive from task and protected interface", N);
10609 end Check_Interfaces;
10611 ------------------------------------
10612 -- Check_Or_Process_Discriminants --
10613 ------------------------------------
10615 -- If an incomplete or private type declaration was already given for the
10616 -- type, the discriminants may have already been processed if they were
10617 -- present on the incomplete declaration. In this case a full conformance
10618 -- check has been performed in Find_Type_Name, and we then recheck here
10619 -- some properties that can't be checked on the partial view alone.
10620 -- Otherwise we call Process_Discriminants.
10622 procedure Check_Or_Process_Discriminants
10625 Prev : Entity_Id := Empty)
10628 if Has_Discriminants (T) then
10630 -- Discriminants are already set on T if they were already present
10631 -- on the partial view. Make them visible to component declarations.
10635 -- Discriminant on T (full view) referencing expr on partial view
10637 Prev_D : Entity_Id;
10638 -- Entity of corresponding discriminant on partial view
10641 -- Discriminant specification for full view, expression is the
10642 -- syntactic copy on full view (which has been checked for
10643 -- conformance with partial view), only used here to post error
10647 D := First_Discriminant (T);
10648 New_D := First (Discriminant_Specifications (N));
10649 while Present (D) loop
10650 Prev_D := Current_Entity (D);
10651 Set_Current_Entity (D);
10652 Set_Is_Immediately_Visible (D);
10653 Set_Homonym (D, Prev_D);
10655 -- Handle the case where there is an untagged partial view and
10656 -- the full view is tagged: must disallow discriminants with
10657 -- defaults, unless compiling for Ada 2012, which allows a
10658 -- limited tagged type to have defaulted discriminants (see
10659 -- AI05-0214). However, suppress error here if it was already
10660 -- reported on the default expression of the partial view.
10662 if Is_Tagged_Type (T)
10663 and then Present (Expression (Parent (D)))
10664 and then (not Is_Limited_Type (Current_Scope)
10665 or else Ada_Version < Ada_2012)
10666 and then not Error_Posted (Expression (Parent (D)))
10668 if Ada_Version >= Ada_2012 then
10670 ("discriminants of nonlimited tagged type cannot have"
10672 Expression (New_D));
10675 ("discriminants of tagged type cannot have defaults",
10676 Expression (New_D));
10680 -- Ada 2005 (AI-230): Access discriminant allowed in
10681 -- non-limited record types.
10683 if Ada_Version < Ada_2005 then
10685 -- This restriction gets applied to the full type here. It
10686 -- has already been applied earlier to the partial view.
10688 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10691 Next_Discriminant (D);
10696 elsif Present (Discriminant_Specifications (N)) then
10697 Process_Discriminants (N, Prev);
10699 end Check_Or_Process_Discriminants;
10701 ----------------------
10702 -- Check_Real_Bound --
10703 ----------------------
10705 procedure Check_Real_Bound (Bound : Node_Id) is
10707 if not Is_Real_Type (Etype (Bound)) then
10709 ("bound in real type definition must be of real type", Bound);
10711 elsif not Is_OK_Static_Expression (Bound) then
10712 Flag_Non_Static_Expr
10713 ("non-static expression used for real type bound!", Bound);
10720 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10722 Resolve (Bound, Standard_Float);
10723 end Check_Real_Bound;
10725 ------------------------------
10726 -- Complete_Private_Subtype --
10727 ------------------------------
10729 procedure Complete_Private_Subtype
10732 Full_Base : Entity_Id;
10733 Related_Nod : Node_Id)
10735 Save_Next_Entity : Entity_Id;
10736 Save_Homonym : Entity_Id;
10739 -- Set semantic attributes for (implicit) private subtype completion.
10740 -- If the full type has no discriminants, then it is a copy of the full
10741 -- view of the base. Otherwise, it is a subtype of the base with a
10742 -- possible discriminant constraint. Save and restore the original
10743 -- Next_Entity field of full to ensure that the calls to Copy_Node
10744 -- do not corrupt the entity chain.
10746 -- Note that the type of the full view is the same entity as the type of
10747 -- the partial view. In this fashion, the subtype has access to the
10748 -- correct view of the parent.
10750 Save_Next_Entity := Next_Entity (Full);
10751 Save_Homonym := Homonym (Priv);
10753 case Ekind (Full_Base) is
10754 when E_Record_Type |
10760 Copy_Node (Priv, Full);
10762 Set_Has_Discriminants
10763 (Full, Has_Discriminants (Full_Base));
10764 Set_Has_Unknown_Discriminants
10765 (Full, Has_Unknown_Discriminants (Full_Base));
10766 Set_First_Entity (Full, First_Entity (Full_Base));
10767 Set_Last_Entity (Full, Last_Entity (Full_Base));
10769 -- If the underlying base type is constrained, we know that the
10770 -- full view of the subtype is constrained as well (the converse
10771 -- is not necessarily true).
10773 if Is_Constrained (Full_Base) then
10774 Set_Is_Constrained (Full);
10778 Copy_Node (Full_Base, Full);
10780 Set_Chars (Full, Chars (Priv));
10781 Conditional_Delay (Full, Priv);
10782 Set_Sloc (Full, Sloc (Priv));
10785 Set_Next_Entity (Full, Save_Next_Entity);
10786 Set_Homonym (Full, Save_Homonym);
10787 Set_Associated_Node_For_Itype (Full, Related_Nod);
10789 -- Set common attributes for all subtypes: kind, convention, etc.
10791 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10792 Set_Convention (Full, Convention (Full_Base));
10794 -- The Etype of the full view is inconsistent. Gigi needs to see the
10795 -- structural full view, which is what the current scheme gives:
10796 -- the Etype of the full view is the etype of the full base. However,
10797 -- if the full base is a derived type, the full view then looks like
10798 -- a subtype of the parent, not a subtype of the full base. If instead
10801 -- Set_Etype (Full, Full_Base);
10803 -- then we get inconsistencies in the front-end (confusion between
10804 -- views). Several outstanding bugs are related to this ???
10806 Set_Is_First_Subtype (Full, False);
10807 Set_Scope (Full, Scope (Priv));
10808 Set_Size_Info (Full, Full_Base);
10809 Set_RM_Size (Full, RM_Size (Full_Base));
10810 Set_Is_Itype (Full);
10812 -- A subtype of a private-type-without-discriminants, whose full-view
10813 -- has discriminants with default expressions, is not constrained.
10815 if not Has_Discriminants (Priv) then
10816 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10818 if Has_Discriminants (Full_Base) then
10819 Set_Discriminant_Constraint
10820 (Full, Discriminant_Constraint (Full_Base));
10822 -- The partial view may have been indefinite, the full view
10825 Set_Has_Unknown_Discriminants
10826 (Full, Has_Unknown_Discriminants (Full_Base));
10830 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10831 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10833 -- Freeze the private subtype entity if its parent is delayed, and not
10834 -- already frozen. We skip this processing if the type is an anonymous
10835 -- subtype of a record component, or is the corresponding record of a
10836 -- protected type, since ???
10838 if not Is_Type (Scope (Full)) then
10839 Set_Has_Delayed_Freeze (Full,
10840 Has_Delayed_Freeze (Full_Base)
10841 and then (not Is_Frozen (Full_Base)));
10844 Set_Freeze_Node (Full, Empty);
10845 Set_Is_Frozen (Full, False);
10846 Set_Full_View (Priv, Full);
10848 if Has_Discriminants (Full) then
10849 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10850 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10852 if Has_Unknown_Discriminants (Full) then
10853 Set_Discriminant_Constraint (Full, No_Elist);
10857 if Ekind (Full_Base) = E_Record_Type
10858 and then Has_Discriminants (Full_Base)
10859 and then Has_Discriminants (Priv) -- might not, if errors
10860 and then not Has_Unknown_Discriminants (Priv)
10861 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10863 Create_Constrained_Components
10864 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10866 -- If the full base is itself derived from private, build a congruent
10867 -- subtype of its underlying type, for use by the back end. For a
10868 -- constrained record component, the declaration cannot be placed on
10869 -- the component list, but it must nevertheless be built an analyzed, to
10870 -- supply enough information for Gigi to compute the size of component.
10872 elsif Ekind (Full_Base) in Private_Kind
10873 and then Is_Derived_Type (Full_Base)
10874 and then Has_Discriminants (Full_Base)
10875 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10877 if not Is_Itype (Priv)
10879 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10881 Build_Underlying_Full_View
10882 (Parent (Priv), Full, Etype (Full_Base));
10884 elsif Nkind (Related_Nod) = N_Component_Declaration then
10885 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10888 elsif Is_Record_Type (Full_Base) then
10890 -- Show Full is simply a renaming of Full_Base
10892 Set_Cloned_Subtype (Full, Full_Base);
10895 -- It is unsafe to share the bounds of a scalar type, because the Itype
10896 -- is elaborated on demand, and if a bound is non-static then different
10897 -- orders of elaboration in different units will lead to different
10898 -- external symbols.
10900 if Is_Scalar_Type (Full_Base) then
10901 Set_Scalar_Range (Full,
10902 Make_Range (Sloc (Related_Nod),
10904 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10906 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10908 -- This completion inherits the bounds of the full parent, but if
10909 -- the parent is an unconstrained floating point type, so is the
10912 if Is_Floating_Point_Type (Full_Base) then
10913 Set_Includes_Infinities
10914 (Scalar_Range (Full), Has_Infinities (Full_Base));
10918 -- ??? It seems that a lot of fields are missing that should be copied
10919 -- from Full_Base to Full. Here are some that are introduced in a
10920 -- non-disruptive way but a cleanup is necessary.
10922 if Is_Tagged_Type (Full_Base) then
10923 Set_Is_Tagged_Type (Full);
10924 Set_Direct_Primitive_Operations (Full,
10925 Direct_Primitive_Operations (Full_Base));
10927 -- Inherit class_wide type of full_base in case the partial view was
10928 -- not tagged. Otherwise it has already been created when the private
10929 -- subtype was analyzed.
10931 if No (Class_Wide_Type (Full)) then
10932 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10935 -- If this is a subtype of a protected or task type, constrain its
10936 -- corresponding record, unless this is a subtype without constraints,
10937 -- i.e. a simple renaming as with an actual subtype in an instance.
10939 elsif Is_Concurrent_Type (Full_Base) then
10940 if Has_Discriminants (Full)
10941 and then Present (Corresponding_Record_Type (Full_Base))
10943 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10945 Set_Corresponding_Record_Type (Full,
10946 Constrain_Corresponding_Record
10947 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
10950 Set_Corresponding_Record_Type (Full,
10951 Corresponding_Record_Type (Full_Base));
10955 -- Link rep item chain, and also setting of Has_Predicates from private
10956 -- subtype to full subtype, since we will need these on the full subtype
10957 -- to create the predicate function. Note that the full subtype may
10958 -- already have rep items, inherited from the full view of the base
10959 -- type, so we must be sure not to overwrite these entries.
10964 Next_Item : Node_Id;
10967 Item := First_Rep_Item (Full);
10969 -- If no existing rep items on full type, we can just link directly
10970 -- to the list of items on the private type.
10973 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10975 -- Otherwise, search to the end of items currently linked to the full
10976 -- subtype and append the private items to the end. However, if Priv
10977 -- and Full already have the same list of rep items, then the append
10978 -- is not done, as that would create a circularity.
10980 elsif Item /= First_Rep_Item (Priv) then
10984 Next_Item := Next_Rep_Item (Item);
10985 exit when No (Next_Item);
10988 -- If the private view has aspect specifications, the full view
10989 -- inherits them. Since these aspects may already have been
10990 -- attached to the full view during derivation, do not append
10991 -- them if already present.
10993 if Item = First_Rep_Item (Priv) then
10999 -- And link the private type items at the end of the chain
11002 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11007 -- Make sure Has_Predicates is set on full type if it is set on the
11008 -- private type. Note that it may already be set on the full type and
11009 -- if so, we don't want to unset it.
11011 if Has_Predicates (Priv) then
11012 Set_Has_Predicates (Full);
11014 end Complete_Private_Subtype;
11016 ----------------------------
11017 -- Constant_Redeclaration --
11018 ----------------------------
11020 procedure Constant_Redeclaration
11025 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11026 Obj_Def : constant Node_Id := Object_Definition (N);
11029 procedure Check_Possible_Deferred_Completion
11030 (Prev_Id : Entity_Id;
11031 Prev_Obj_Def : Node_Id;
11032 Curr_Obj_Def : Node_Id);
11033 -- Determine whether the two object definitions describe the partial
11034 -- and the full view of a constrained deferred constant. Generate
11035 -- a subtype for the full view and verify that it statically matches
11036 -- the subtype of the partial view.
11038 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11039 -- If deferred constant is an access type initialized with an allocator,
11040 -- check whether there is an illegal recursion in the definition,
11041 -- through a default value of some record subcomponent. This is normally
11042 -- detected when generating init procs, but requires this additional
11043 -- mechanism when expansion is disabled.
11045 ----------------------------------------
11046 -- Check_Possible_Deferred_Completion --
11047 ----------------------------------------
11049 procedure Check_Possible_Deferred_Completion
11050 (Prev_Id : Entity_Id;
11051 Prev_Obj_Def : Node_Id;
11052 Curr_Obj_Def : Node_Id)
11055 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11056 and then Present (Constraint (Prev_Obj_Def))
11057 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11058 and then Present (Constraint (Curr_Obj_Def))
11061 Loc : constant Source_Ptr := Sloc (N);
11062 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11063 Decl : constant Node_Id :=
11064 Make_Subtype_Declaration (Loc,
11065 Defining_Identifier => Def_Id,
11066 Subtype_Indication =>
11067 Relocate_Node (Curr_Obj_Def));
11070 Insert_Before_And_Analyze (N, Decl);
11071 Set_Etype (Id, Def_Id);
11073 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11074 Error_Msg_Sloc := Sloc (Prev_Id);
11075 Error_Msg_N ("subtype does not statically match deferred " &
11076 "declaration#", N);
11080 end Check_Possible_Deferred_Completion;
11082 ---------------------------------
11083 -- Check_Recursive_Declaration --
11084 ---------------------------------
11086 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11090 if Is_Record_Type (Typ) then
11091 Comp := First_Component (Typ);
11092 while Present (Comp) loop
11093 if Comes_From_Source (Comp) then
11094 if Present (Expression (Parent (Comp)))
11095 and then Is_Entity_Name (Expression (Parent (Comp)))
11096 and then Entity (Expression (Parent (Comp))) = Prev
11098 Error_Msg_Sloc := Sloc (Parent (Comp));
11100 ("illegal circularity with declaration for&#",
11104 elsif Is_Record_Type (Etype (Comp)) then
11105 Check_Recursive_Declaration (Etype (Comp));
11109 Next_Component (Comp);
11112 end Check_Recursive_Declaration;
11114 -- Start of processing for Constant_Redeclaration
11117 if Nkind (Parent (Prev)) = N_Object_Declaration then
11118 if Nkind (Object_Definition
11119 (Parent (Prev))) = N_Subtype_Indication
11121 -- Find type of new declaration. The constraints of the two
11122 -- views must match statically, but there is no point in
11123 -- creating an itype for the full view.
11125 if Nkind (Obj_Def) = N_Subtype_Indication then
11126 Find_Type (Subtype_Mark (Obj_Def));
11127 New_T := Entity (Subtype_Mark (Obj_Def));
11130 Find_Type (Obj_Def);
11131 New_T := Entity (Obj_Def);
11137 -- The full view may impose a constraint, even if the partial
11138 -- view does not, so construct the subtype.
11140 New_T := Find_Type_Of_Object (Obj_Def, N);
11145 -- Current declaration is illegal, diagnosed below in Enter_Name
11151 -- If previous full declaration or a renaming declaration exists, or if
11152 -- a homograph is present, let Enter_Name handle it, either with an
11153 -- error or with the removal of an overridden implicit subprogram.
11154 -- The previous one is a full declaration if it has an expression
11155 -- (which in the case of an aggregate is indicated by the Init flag).
11157 if Ekind (Prev) /= E_Constant
11158 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11159 or else Present (Expression (Parent (Prev)))
11160 or else Has_Init_Expression (Parent (Prev))
11161 or else Present (Full_View (Prev))
11165 -- Verify that types of both declarations match, or else that both types
11166 -- are anonymous access types whose designated subtypes statically match
11167 -- (as allowed in Ada 2005 by AI-385).
11169 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11171 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11172 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11173 or else Is_Access_Constant (Etype (New_T)) /=
11174 Is_Access_Constant (Etype (Prev))
11175 or else Can_Never_Be_Null (Etype (New_T)) /=
11176 Can_Never_Be_Null (Etype (Prev))
11177 or else Null_Exclusion_Present (Parent (Prev)) /=
11178 Null_Exclusion_Present (Parent (Id))
11179 or else not Subtypes_Statically_Match
11180 (Designated_Type (Etype (Prev)),
11181 Designated_Type (Etype (New_T))))
11183 Error_Msg_Sloc := Sloc (Prev);
11184 Error_Msg_N ("type does not match declaration#", N);
11185 Set_Full_View (Prev, Id);
11186 Set_Etype (Id, Any_Type);
11189 Null_Exclusion_Present (Parent (Prev))
11190 and then not Null_Exclusion_Present (N)
11192 Error_Msg_Sloc := Sloc (Prev);
11193 Error_Msg_N ("null-exclusion does not match declaration#", N);
11194 Set_Full_View (Prev, Id);
11195 Set_Etype (Id, Any_Type);
11197 -- If so, process the full constant declaration
11200 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11201 -- the deferred declaration is constrained, then the subtype defined
11202 -- by the subtype_indication in the full declaration shall match it
11205 Check_Possible_Deferred_Completion
11207 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11208 Curr_Obj_Def => Obj_Def);
11210 Set_Full_View (Prev, Id);
11211 Set_Is_Public (Id, Is_Public (Prev));
11212 Set_Is_Internal (Id);
11213 Append_Entity (Id, Current_Scope);
11215 -- Check ALIASED present if present before (RM 7.4(7))
11217 if Is_Aliased (Prev)
11218 and then not Aliased_Present (N)
11220 Error_Msg_Sloc := Sloc (Prev);
11221 Error_Msg_N ("ALIASED required (see declaration#)", N);
11224 -- Check that placement is in private part and that the incomplete
11225 -- declaration appeared in the visible part.
11227 if Ekind (Current_Scope) = E_Package
11228 and then not In_Private_Part (Current_Scope)
11230 Error_Msg_Sloc := Sloc (Prev);
11232 ("full constant for declaration#"
11233 & " must be in private part", N);
11235 elsif Ekind (Current_Scope) = E_Package
11237 List_Containing (Parent (Prev)) /=
11238 Visible_Declarations (Package_Specification (Current_Scope))
11241 ("deferred constant must be declared in visible part",
11245 if Is_Access_Type (T)
11246 and then Nkind (Expression (N)) = N_Allocator
11248 Check_Recursive_Declaration (Designated_Type (T));
11251 -- A deferred constant is a visible entity. If type has invariants,
11252 -- verify that the initial value satisfies them.
11254 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
11256 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
11259 end Constant_Redeclaration;
11261 ----------------------
11262 -- Constrain_Access --
11263 ----------------------
11265 procedure Constrain_Access
11266 (Def_Id : in out Entity_Id;
11268 Related_Nod : Node_Id)
11270 T : constant Entity_Id := Entity (Subtype_Mark (S));
11271 Desig_Type : constant Entity_Id := Designated_Type (T);
11272 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
11273 Constraint_OK : Boolean := True;
11276 if Is_Array_Type (Desig_Type) then
11277 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
11279 elsif (Is_Record_Type (Desig_Type)
11280 or else Is_Incomplete_Or_Private_Type (Desig_Type))
11281 and then not Is_Constrained (Desig_Type)
11283 -- ??? The following code is a temporary bypass to ignore a
11284 -- discriminant constraint on access type if it is constraining
11285 -- the current record. Avoid creating the implicit subtype of the
11286 -- record we are currently compiling since right now, we cannot
11287 -- handle these. For now, just return the access type itself.
11289 if Desig_Type = Current_Scope
11290 and then No (Def_Id)
11292 Set_Ekind (Desig_Subtype, E_Record_Subtype);
11293 Def_Id := Entity (Subtype_Mark (S));
11295 -- This call added to ensure that the constraint is analyzed
11296 -- (needed for a B test). Note that we still return early from
11297 -- this procedure to avoid recursive processing. ???
11299 Constrain_Discriminated_Type
11300 (Desig_Subtype, S, Related_Nod, For_Access => True);
11304 -- Enforce rule that the constraint is illegal if there is an
11305 -- unconstrained view of the designated type. This means that the
11306 -- partial view (either a private type declaration or a derivation
11307 -- from a private type) has no discriminants. (Defect Report
11308 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
11310 -- Rule updated for Ada 2005: The private type is said to have
11311 -- a constrained partial view, given that objects of the type
11312 -- can be declared. Furthermore, the rule applies to all access
11313 -- types, unlike the rule concerning default discriminants (see
11316 if (Ekind (T) = E_General_Access_Type
11317 or else Ada_Version >= Ada_2005)
11318 and then Has_Private_Declaration (Desig_Type)
11319 and then In_Open_Scopes (Scope (Desig_Type))
11320 and then Has_Discriminants (Desig_Type)
11323 Pack : constant Node_Id :=
11324 Unit_Declaration_Node (Scope (Desig_Type));
11329 if Nkind (Pack) = N_Package_Declaration then
11330 Decls := Visible_Declarations (Specification (Pack));
11331 Decl := First (Decls);
11332 while Present (Decl) loop
11333 if (Nkind (Decl) = N_Private_Type_Declaration
11335 Chars (Defining_Identifier (Decl)) =
11336 Chars (Desig_Type))
11339 (Nkind (Decl) = N_Full_Type_Declaration
11341 Chars (Defining_Identifier (Decl)) =
11343 and then Is_Derived_Type (Desig_Type)
11345 Has_Private_Declaration (Etype (Desig_Type)))
11347 if No (Discriminant_Specifications (Decl)) then
11349 ("cannot constrain access type if designated " &
11350 "type has constrained partial view", S);
11362 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
11363 For_Access => True);
11365 elsif (Is_Task_Type (Desig_Type)
11366 or else Is_Protected_Type (Desig_Type))
11367 and then not Is_Constrained (Desig_Type)
11369 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
11372 Error_Msg_N ("invalid constraint on access type", S);
11373 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
11374 Constraint_OK := False;
11377 if No (Def_Id) then
11378 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
11380 Set_Ekind (Def_Id, E_Access_Subtype);
11383 if Constraint_OK then
11384 Set_Etype (Def_Id, Base_Type (T));
11386 if Is_Private_Type (Desig_Type) then
11387 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
11390 Set_Etype (Def_Id, Any_Type);
11393 Set_Size_Info (Def_Id, T);
11394 Set_Is_Constrained (Def_Id, Constraint_OK);
11395 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
11396 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11397 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
11399 Conditional_Delay (Def_Id, T);
11401 -- AI-363 : Subtypes of general access types whose designated types have
11402 -- default discriminants are disallowed. In instances, the rule has to
11403 -- be checked against the actual, of which T is the subtype. In a
11404 -- generic body, the rule is checked assuming that the actual type has
11405 -- defaulted discriminants.
11407 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
11408 if Ekind (Base_Type (T)) = E_General_Access_Type
11409 and then Has_Defaulted_Discriminants (Desig_Type)
11411 if Ada_Version < Ada_2005 then
11413 ("access subtype of general access type would not " &
11414 "be allowed in Ada 2005?y?", S);
11417 ("access subtype of general access type not allowed", S);
11420 Error_Msg_N ("\discriminants have defaults", S);
11422 elsif Is_Access_Type (T)
11423 and then Is_Generic_Type (Desig_Type)
11424 and then Has_Discriminants (Desig_Type)
11425 and then In_Package_Body (Current_Scope)
11427 if Ada_Version < Ada_2005 then
11429 ("access subtype would not be allowed in generic body " &
11430 "in Ada 2005?y?", S);
11433 ("access subtype not allowed in generic body", S);
11437 ("\designated type is a discriminated formal", S);
11440 end Constrain_Access;
11442 ---------------------
11443 -- Constrain_Array --
11444 ---------------------
11446 procedure Constrain_Array
11447 (Def_Id : in out Entity_Id;
11449 Related_Nod : Node_Id;
11450 Related_Id : Entity_Id;
11451 Suffix : Character)
11453 C : constant Node_Id := Constraint (SI);
11454 Number_Of_Constraints : Nat := 0;
11457 Constraint_OK : Boolean := True;
11460 T := Entity (Subtype_Mark (SI));
11462 if Is_Access_Type (T) then
11463 T := Designated_Type (T);
11466 -- If an index constraint follows a subtype mark in a subtype indication
11467 -- then the type or subtype denoted by the subtype mark must not already
11468 -- impose an index constraint. The subtype mark must denote either an
11469 -- unconstrained array type or an access type whose designated type
11470 -- is such an array type... (RM 3.6.1)
11472 if Is_Constrained (T) then
11473 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
11474 Constraint_OK := False;
11477 S := First (Constraints (C));
11478 while Present (S) loop
11479 Number_Of_Constraints := Number_Of_Constraints + 1;
11483 -- In either case, the index constraint must provide a discrete
11484 -- range for each index of the array type and the type of each
11485 -- discrete range must be the same as that of the corresponding
11486 -- index. (RM 3.6.1)
11488 if Number_Of_Constraints /= Number_Dimensions (T) then
11489 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
11490 Constraint_OK := False;
11493 S := First (Constraints (C));
11494 Index := First_Index (T);
11497 -- Apply constraints to each index type
11499 for J in 1 .. Number_Of_Constraints loop
11500 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
11508 if No (Def_Id) then
11510 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
11511 Set_Parent (Def_Id, Related_Nod);
11514 Set_Ekind (Def_Id, E_Array_Subtype);
11517 Set_Size_Info (Def_Id, (T));
11518 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11519 Set_Etype (Def_Id, Base_Type (T));
11521 if Constraint_OK then
11522 Set_First_Index (Def_Id, First (Constraints (C)));
11524 Set_First_Index (Def_Id, First_Index (T));
11527 Set_Is_Constrained (Def_Id, True);
11528 Set_Is_Aliased (Def_Id, Is_Aliased (T));
11529 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11531 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
11532 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
11534 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
11535 -- We need to initialize the attribute because if Def_Id is previously
11536 -- analyzed through a limited_with clause, it will have the attributes
11537 -- of an incomplete type, one of which is an Elist that overlaps the
11538 -- Packed_Array_Impl_Type field.
11540 Set_Packed_Array_Impl_Type (Def_Id, Empty);
11542 -- Build a freeze node if parent still needs one. Also make sure that
11543 -- the Depends_On_Private status is set because the subtype will need
11544 -- reprocessing at the time the base type does, and also we must set a
11545 -- conditional delay.
11547 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
11548 Conditional_Delay (Def_Id, T);
11549 end Constrain_Array;
11551 ------------------------------
11552 -- Constrain_Component_Type --
11553 ------------------------------
11555 function Constrain_Component_Type
11557 Constrained_Typ : Entity_Id;
11558 Related_Node : Node_Id;
11560 Constraints : Elist_Id) return Entity_Id
11562 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
11563 Compon_Type : constant Entity_Id := Etype (Comp);
11565 function Build_Constrained_Array_Type
11566 (Old_Type : Entity_Id) return Entity_Id;
11567 -- If Old_Type is an array type, one of whose indexes is constrained
11568 -- by a discriminant, build an Itype whose constraint replaces the
11569 -- discriminant with its value in the constraint.
11571 function Build_Constrained_Discriminated_Type
11572 (Old_Type : Entity_Id) return Entity_Id;
11573 -- Ditto for record components
11575 function Build_Constrained_Access_Type
11576 (Old_Type : Entity_Id) return Entity_Id;
11577 -- Ditto for access types. Makes use of previous two functions, to
11578 -- constrain designated type.
11580 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
11581 -- T is an array or discriminated type, C is a list of constraints
11582 -- that apply to T. This routine builds the constrained subtype.
11584 function Is_Discriminant (Expr : Node_Id) return Boolean;
11585 -- Returns True if Expr is a discriminant
11587 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
11588 -- Find the value of discriminant Discrim in Constraint
11590 -----------------------------------
11591 -- Build_Constrained_Access_Type --
11592 -----------------------------------
11594 function Build_Constrained_Access_Type
11595 (Old_Type : Entity_Id) return Entity_Id
11597 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
11599 Desig_Subtype : Entity_Id;
11603 -- if the original access type was not embedded in the enclosing
11604 -- type definition, there is no need to produce a new access
11605 -- subtype. In fact every access type with an explicit constraint
11606 -- generates an itype whose scope is the enclosing record.
11608 if not Is_Type (Scope (Old_Type)) then
11611 elsif Is_Array_Type (Desig_Type) then
11612 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
11614 elsif Has_Discriminants (Desig_Type) then
11616 -- This may be an access type to an enclosing record type for
11617 -- which we are constructing the constrained components. Return
11618 -- the enclosing record subtype. This is not always correct,
11619 -- but avoids infinite recursion. ???
11621 Desig_Subtype := Any_Type;
11623 for J in reverse 0 .. Scope_Stack.Last loop
11624 Scop := Scope_Stack.Table (J).Entity;
11627 and then Base_Type (Scop) = Base_Type (Desig_Type)
11629 Desig_Subtype := Scop;
11632 exit when not Is_Type (Scop);
11635 if Desig_Subtype = Any_Type then
11637 Build_Constrained_Discriminated_Type (Desig_Type);
11644 if Desig_Subtype /= Desig_Type then
11646 -- The Related_Node better be here or else we won't be able
11647 -- to attach new itypes to a node in the tree.
11649 pragma Assert (Present (Related_Node));
11651 Itype := Create_Itype (E_Access_Subtype, Related_Node);
11653 Set_Etype (Itype, Base_Type (Old_Type));
11654 Set_Size_Info (Itype, (Old_Type));
11655 Set_Directly_Designated_Type (Itype, Desig_Subtype);
11656 Set_Depends_On_Private (Itype, Has_Private_Component
11658 Set_Is_Access_Constant (Itype, Is_Access_Constant
11661 -- The new itype needs freezing when it depends on a not frozen
11662 -- type and the enclosing subtype needs freezing.
11664 if Has_Delayed_Freeze (Constrained_Typ)
11665 and then not Is_Frozen (Constrained_Typ)
11667 Conditional_Delay (Itype, Base_Type (Old_Type));
11675 end Build_Constrained_Access_Type;
11677 ----------------------------------
11678 -- Build_Constrained_Array_Type --
11679 ----------------------------------
11681 function Build_Constrained_Array_Type
11682 (Old_Type : Entity_Id) return Entity_Id
11686 Old_Index : Node_Id;
11687 Range_Node : Node_Id;
11688 Constr_List : List_Id;
11690 Need_To_Create_Itype : Boolean := False;
11693 Old_Index := First_Index (Old_Type);
11694 while Present (Old_Index) loop
11695 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11697 if Is_Discriminant (Lo_Expr)
11698 or else Is_Discriminant (Hi_Expr)
11700 Need_To_Create_Itype := True;
11703 Next_Index (Old_Index);
11706 if Need_To_Create_Itype then
11707 Constr_List := New_List;
11709 Old_Index := First_Index (Old_Type);
11710 while Present (Old_Index) loop
11711 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11713 if Is_Discriminant (Lo_Expr) then
11714 Lo_Expr := Get_Discr_Value (Lo_Expr);
11717 if Is_Discriminant (Hi_Expr) then
11718 Hi_Expr := Get_Discr_Value (Hi_Expr);
11723 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11725 Append (Range_Node, To => Constr_List);
11727 Next_Index (Old_Index);
11730 return Build_Subtype (Old_Type, Constr_List);
11735 end Build_Constrained_Array_Type;
11737 ------------------------------------------
11738 -- Build_Constrained_Discriminated_Type --
11739 ------------------------------------------
11741 function Build_Constrained_Discriminated_Type
11742 (Old_Type : Entity_Id) return Entity_Id
11745 Constr_List : List_Id;
11746 Old_Constraint : Elmt_Id;
11748 Need_To_Create_Itype : Boolean := False;
11751 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11752 while Present (Old_Constraint) loop
11753 Expr := Node (Old_Constraint);
11755 if Is_Discriminant (Expr) then
11756 Need_To_Create_Itype := True;
11759 Next_Elmt (Old_Constraint);
11762 if Need_To_Create_Itype then
11763 Constr_List := New_List;
11765 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11766 while Present (Old_Constraint) loop
11767 Expr := Node (Old_Constraint);
11769 if Is_Discriminant (Expr) then
11770 Expr := Get_Discr_Value (Expr);
11773 Append (New_Copy_Tree (Expr), To => Constr_List);
11775 Next_Elmt (Old_Constraint);
11778 return Build_Subtype (Old_Type, Constr_List);
11783 end Build_Constrained_Discriminated_Type;
11785 -------------------
11786 -- Build_Subtype --
11787 -------------------
11789 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11791 Subtyp_Decl : Node_Id;
11792 Def_Id : Entity_Id;
11793 Btyp : Entity_Id := Base_Type (T);
11796 -- The Related_Node better be here or else we won't be able to
11797 -- attach new itypes to a node in the tree.
11799 pragma Assert (Present (Related_Node));
11801 -- If the view of the component's type is incomplete or private
11802 -- with unknown discriminants, then the constraint must be applied
11803 -- to the full type.
11805 if Has_Unknown_Discriminants (Btyp)
11806 and then Present (Underlying_Type (Btyp))
11808 Btyp := Underlying_Type (Btyp);
11812 Make_Subtype_Indication (Loc,
11813 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11814 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11816 Def_Id := Create_Itype (Ekind (T), Related_Node);
11819 Make_Subtype_Declaration (Loc,
11820 Defining_Identifier => Def_Id,
11821 Subtype_Indication => Indic);
11823 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11825 -- Itypes must be analyzed with checks off (see package Itypes)
11827 Analyze (Subtyp_Decl, Suppress => All_Checks);
11832 ---------------------
11833 -- Get_Discr_Value --
11834 ---------------------
11836 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11841 -- The discriminant may be declared for the type, in which case we
11842 -- find it by iterating over the list of discriminants. If the
11843 -- discriminant is inherited from a parent type, it appears as the
11844 -- corresponding discriminant of the current type. This will be the
11845 -- case when constraining an inherited component whose constraint is
11846 -- given by a discriminant of the parent.
11848 D := First_Discriminant (Typ);
11849 E := First_Elmt (Constraints);
11851 while Present (D) loop
11852 if D = Entity (Discrim)
11853 or else D = CR_Discriminant (Entity (Discrim))
11854 or else Corresponding_Discriminant (D) = Entity (Discrim)
11859 Next_Discriminant (D);
11863 -- The Corresponding_Discriminant mechanism is incomplete, because
11864 -- the correspondence between new and old discriminants is not one
11865 -- to one: one new discriminant can constrain several old ones. In
11866 -- that case, scan sequentially the stored_constraint, the list of
11867 -- discriminants of the parents, and the constraints.
11869 -- Previous code checked for the present of the Stored_Constraint
11870 -- list for the derived type, but did not use it at all. Should it
11871 -- be present when the component is a discriminated task type?
11873 if Is_Derived_Type (Typ)
11874 and then Scope (Entity (Discrim)) = Etype (Typ)
11876 D := First_Discriminant (Etype (Typ));
11877 E := First_Elmt (Constraints);
11878 while Present (D) loop
11879 if D = Entity (Discrim) then
11883 Next_Discriminant (D);
11888 -- Something is wrong if we did not find the value
11890 raise Program_Error;
11891 end Get_Discr_Value;
11893 ---------------------
11894 -- Is_Discriminant --
11895 ---------------------
11897 function Is_Discriminant (Expr : Node_Id) return Boolean is
11898 Discrim_Scope : Entity_Id;
11901 if Denotes_Discriminant (Expr) then
11902 Discrim_Scope := Scope (Entity (Expr));
11904 -- Either we have a reference to one of Typ's discriminants,
11906 pragma Assert (Discrim_Scope = Typ
11908 -- or to the discriminants of the parent type, in the case
11909 -- of a derivation of a tagged type with variants.
11911 or else Discrim_Scope = Etype (Typ)
11912 or else Full_View (Discrim_Scope) = Etype (Typ)
11914 -- or same as above for the case where the discriminants
11915 -- were declared in Typ's private view.
11917 or else (Is_Private_Type (Discrim_Scope)
11918 and then Chars (Discrim_Scope) = Chars (Typ))
11920 -- or else we are deriving from the full view and the
11921 -- discriminant is declared in the private entity.
11923 or else (Is_Private_Type (Typ)
11924 and then Chars (Discrim_Scope) = Chars (Typ))
11926 -- Or we are constrained the corresponding record of a
11927 -- synchronized type that completes a private declaration.
11929 or else (Is_Concurrent_Record_Type (Typ)
11931 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11933 -- or we have a class-wide type, in which case make sure the
11934 -- discriminant found belongs to the root type.
11936 or else (Is_Class_Wide_Type (Typ)
11937 and then Etype (Typ) = Discrim_Scope));
11942 -- In all other cases we have something wrong
11945 end Is_Discriminant;
11947 -- Start of processing for Constrain_Component_Type
11950 if Nkind (Parent (Comp)) = N_Component_Declaration
11951 and then Comes_From_Source (Parent (Comp))
11952 and then Comes_From_Source
11953 (Subtype_Indication (Component_Definition (Parent (Comp))))
11956 (Subtype_Indication (Component_Definition (Parent (Comp))))
11958 return Compon_Type;
11960 elsif Is_Array_Type (Compon_Type) then
11961 return Build_Constrained_Array_Type (Compon_Type);
11963 elsif Has_Discriminants (Compon_Type) then
11964 return Build_Constrained_Discriminated_Type (Compon_Type);
11966 elsif Is_Access_Type (Compon_Type) then
11967 return Build_Constrained_Access_Type (Compon_Type);
11970 return Compon_Type;
11972 end Constrain_Component_Type;
11974 --------------------------
11975 -- Constrain_Concurrent --
11976 --------------------------
11978 -- For concurrent types, the associated record value type carries the same
11979 -- discriminants, so when we constrain a concurrent type, we must constrain
11980 -- the corresponding record type as well.
11982 procedure Constrain_Concurrent
11983 (Def_Id : in out Entity_Id;
11985 Related_Nod : Node_Id;
11986 Related_Id : Entity_Id;
11987 Suffix : Character)
11989 -- Retrieve Base_Type to ensure getting to the concurrent type in the
11990 -- case of a private subtype (needed when only doing semantic analysis).
11992 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
11996 if Is_Access_Type (T_Ent) then
11997 T_Ent := Designated_Type (T_Ent);
12000 T_Val := Corresponding_Record_Type (T_Ent);
12002 if Present (T_Val) then
12004 if No (Def_Id) then
12005 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12008 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12010 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12011 Set_Corresponding_Record_Type (Def_Id,
12012 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12015 -- If there is no associated record, expansion is disabled and this
12016 -- is a generic context. Create a subtype in any case, so that
12017 -- semantic analysis can proceed.
12019 if No (Def_Id) then
12020 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12023 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12025 end Constrain_Concurrent;
12027 ------------------------------------
12028 -- Constrain_Corresponding_Record --
12029 ------------------------------------
12031 function Constrain_Corresponding_Record
12032 (Prot_Subt : Entity_Id;
12033 Corr_Rec : Entity_Id;
12034 Related_Nod : Node_Id) return Entity_Id
12036 T_Sub : constant Entity_Id :=
12037 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12040 Set_Etype (T_Sub, Corr_Rec);
12041 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12042 Set_Is_Constrained (T_Sub, True);
12043 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12044 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12046 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12047 Set_Discriminant_Constraint
12048 (T_Sub, Discriminant_Constraint (Prot_Subt));
12049 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12050 Create_Constrained_Components
12051 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12054 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12056 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12057 Conditional_Delay (T_Sub, Corr_Rec);
12060 -- This is a component subtype: it will be frozen in the context of
12061 -- the enclosing record's init_proc, so that discriminant references
12062 -- are resolved to discriminals. (Note: we used to skip freezing
12063 -- altogether in that case, which caused errors downstream for
12064 -- components of a bit packed array type).
12066 Set_Has_Delayed_Freeze (T_Sub);
12070 end Constrain_Corresponding_Record;
12072 -----------------------
12073 -- Constrain_Decimal --
12074 -----------------------
12076 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12077 T : constant Entity_Id := Entity (Subtype_Mark (S));
12078 C : constant Node_Id := Constraint (S);
12079 Loc : constant Source_Ptr := Sloc (C);
12080 Range_Expr : Node_Id;
12081 Digits_Expr : Node_Id;
12086 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12088 if Nkind (C) = N_Range_Constraint then
12089 Range_Expr := Range_Expression (C);
12090 Digits_Val := Digits_Value (T);
12093 pragma Assert (Nkind (C) = N_Digits_Constraint);
12095 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12097 Digits_Expr := Digits_Expression (C);
12098 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12100 Check_Digits_Expression (Digits_Expr);
12101 Digits_Val := Expr_Value (Digits_Expr);
12103 if Digits_Val > Digits_Value (T) then
12105 ("digits expression is incompatible with subtype", C);
12106 Digits_Val := Digits_Value (T);
12109 if Present (Range_Constraint (C)) then
12110 Range_Expr := Range_Expression (Range_Constraint (C));
12112 Range_Expr := Empty;
12116 Set_Etype (Def_Id, Base_Type (T));
12117 Set_Size_Info (Def_Id, (T));
12118 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12119 Set_Delta_Value (Def_Id, Delta_Value (T));
12120 Set_Scale_Value (Def_Id, Scale_Value (T));
12121 Set_Small_Value (Def_Id, Small_Value (T));
12122 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12123 Set_Digits_Value (Def_Id, Digits_Val);
12125 -- Manufacture range from given digits value if no range present
12127 if No (Range_Expr) then
12128 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12132 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12134 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12137 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12138 Set_Discrete_RM_Size (Def_Id);
12140 -- Unconditionally delay the freeze, since we cannot set size
12141 -- information in all cases correctly until the freeze point.
12143 Set_Has_Delayed_Freeze (Def_Id);
12144 end Constrain_Decimal;
12146 ----------------------------------
12147 -- Constrain_Discriminated_Type --
12148 ----------------------------------
12150 procedure Constrain_Discriminated_Type
12151 (Def_Id : Entity_Id;
12153 Related_Nod : Node_Id;
12154 For_Access : Boolean := False)
12156 E : constant Entity_Id := Entity (Subtype_Mark (S));
12159 Elist : Elist_Id := New_Elmt_List;
12161 procedure Fixup_Bad_Constraint;
12162 -- This is called after finding a bad constraint, and after having
12163 -- posted an appropriate error message. The mission is to leave the
12164 -- entity T in as reasonable state as possible.
12166 --------------------------
12167 -- Fixup_Bad_Constraint --
12168 --------------------------
12170 procedure Fixup_Bad_Constraint is
12172 -- Set a reasonable Ekind for the entity. For an incomplete type,
12173 -- we can't do much, but for other types, we can set the proper
12174 -- corresponding subtype kind.
12176 if Ekind (T) = E_Incomplete_Type then
12177 Set_Ekind (Def_Id, Ekind (T));
12179 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12182 -- Set Etype to the known type, to reduce chances of cascaded errors
12184 Set_Etype (Def_Id, E);
12185 Set_Error_Posted (Def_Id);
12186 end Fixup_Bad_Constraint;
12188 -- Start of processing for Constrain_Discriminated_Type
12191 C := Constraint (S);
12193 -- A discriminant constraint is only allowed in a subtype indication,
12194 -- after a subtype mark. This subtype mark must denote either a type
12195 -- with discriminants, or an access type whose designated type is a
12196 -- type with discriminants. A discriminant constraint specifies the
12197 -- values of these discriminants (RM 3.7.2(5)).
12199 T := Base_Type (Entity (Subtype_Mark (S)));
12201 if Is_Access_Type (T) then
12202 T := Designated_Type (T);
12205 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12206 -- Avoid generating an error for access-to-incomplete subtypes.
12208 if Ada_Version >= Ada_2005
12209 and then Ekind (T) = E_Incomplete_Type
12210 and then Nkind (Parent (S)) = N_Subtype_Declaration
12211 and then not Is_Itype (Def_Id)
12213 -- A little sanity check, emit an error message if the type
12214 -- has discriminants to begin with. Type T may be a regular
12215 -- incomplete type or imported via a limited with clause.
12217 if Has_Discriminants (T)
12218 or else (From_Limited_With (T)
12219 and then Present (Non_Limited_View (T))
12220 and then Nkind (Parent (Non_Limited_View (T))) =
12221 N_Full_Type_Declaration
12222 and then Present (Discriminant_Specifications
12223 (Parent (Non_Limited_View (T)))))
12226 ("(Ada 2005) incomplete subtype may not be constrained", C);
12228 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12231 Fixup_Bad_Constraint;
12234 -- Check that the type has visible discriminants. The type may be
12235 -- a private type with unknown discriminants whose full view has
12236 -- discriminants which are invisible.
12238 elsif not Has_Discriminants (T)
12240 (Has_Unknown_Discriminants (T)
12241 and then Is_Private_Type (T))
12243 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12244 Fixup_Bad_Constraint;
12247 elsif Is_Constrained (E)
12248 or else (Ekind (E) = E_Class_Wide_Subtype
12249 and then Present (Discriminant_Constraint (E)))
12251 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
12252 Fixup_Bad_Constraint;
12256 -- T may be an unconstrained subtype (e.g. a generic actual).
12257 -- Constraint applies to the base type.
12259 T := Base_Type (T);
12261 Elist := Build_Discriminant_Constraints (T, S);
12263 -- If the list returned was empty we had an error in building the
12264 -- discriminant constraint. We have also already signalled an error
12265 -- in the incomplete type case
12267 if Is_Empty_Elmt_List (Elist) then
12268 Fixup_Bad_Constraint;
12272 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
12273 end Constrain_Discriminated_Type;
12275 ---------------------------
12276 -- Constrain_Enumeration --
12277 ---------------------------
12279 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
12280 T : constant Entity_Id := Entity (Subtype_Mark (S));
12281 C : constant Node_Id := Constraint (S);
12284 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12286 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
12288 Set_Etype (Def_Id, Base_Type (T));
12289 Set_Size_Info (Def_Id, (T));
12290 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12291 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12293 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12295 Set_Discrete_RM_Size (Def_Id);
12296 end Constrain_Enumeration;
12298 ----------------------
12299 -- Constrain_Float --
12300 ----------------------
12302 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
12303 T : constant Entity_Id := Entity (Subtype_Mark (S));
12309 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
12311 Set_Etype (Def_Id, Base_Type (T));
12312 Set_Size_Info (Def_Id, (T));
12313 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12315 -- Process the constraint
12317 C := Constraint (S);
12319 -- Digits constraint present
12321 if Nkind (C) = N_Digits_Constraint then
12323 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12324 Check_Restriction (No_Obsolescent_Features, C);
12326 if Warn_On_Obsolescent_Feature then
12328 ("subtype digits constraint is an " &
12329 "obsolescent feature (RM J.3(8))?j?", C);
12332 D := Digits_Expression (C);
12333 Analyze_And_Resolve (D, Any_Integer);
12334 Check_Digits_Expression (D);
12335 Set_Digits_Value (Def_Id, Expr_Value (D));
12337 -- Check that digits value is in range. Obviously we can do this
12338 -- at compile time, but it is strictly a runtime check, and of
12339 -- course there is an ACVC test that checks this.
12341 if Digits_Value (Def_Id) > Digits_Value (T) then
12342 Error_Msg_Uint_1 := Digits_Value (T);
12343 Error_Msg_N ("??digits value is too large, maximum is ^", D);
12345 Make_Raise_Constraint_Error (Sloc (D),
12346 Reason => CE_Range_Check_Failed);
12347 Insert_Action (Declaration_Node (Def_Id), Rais);
12350 C := Range_Constraint (C);
12352 -- No digits constraint present
12355 Set_Digits_Value (Def_Id, Digits_Value (T));
12358 -- Range constraint present
12360 if Nkind (C) = N_Range_Constraint then
12361 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12363 -- No range constraint present
12366 pragma Assert (No (C));
12367 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12370 Set_Is_Constrained (Def_Id);
12371 end Constrain_Float;
12373 ---------------------
12374 -- Constrain_Index --
12375 ---------------------
12377 procedure Constrain_Index
12380 Related_Nod : Node_Id;
12381 Related_Id : Entity_Id;
12382 Suffix : Character;
12383 Suffix_Index : Nat)
12385 Def_Id : Entity_Id;
12386 R : Node_Id := Empty;
12387 T : constant Entity_Id := Etype (Index);
12390 if Nkind (S) = N_Range
12392 (Nkind (S) = N_Attribute_Reference
12393 and then Attribute_Name (S) = Name_Range)
12395 -- A Range attribute will be transformed into N_Range by Resolve
12401 Process_Range_Expr_In_Decl (R, T);
12403 if not Error_Posted (S)
12405 (Nkind (S) /= N_Range
12406 or else not Covers (T, (Etype (Low_Bound (S))))
12407 or else not Covers (T, (Etype (High_Bound (S)))))
12409 if Base_Type (T) /= Any_Type
12410 and then Etype (Low_Bound (S)) /= Any_Type
12411 and then Etype (High_Bound (S)) /= Any_Type
12413 Error_Msg_N ("range expected", S);
12417 elsif Nkind (S) = N_Subtype_Indication then
12419 -- The parser has verified that this is a discrete indication
12421 Resolve_Discrete_Subtype_Indication (S, T);
12422 R := Range_Expression (Constraint (S));
12424 -- Capture values of bounds and generate temporaries for them if
12425 -- needed, since checks may cause duplication of the expressions
12426 -- which must not be reevaluated.
12428 -- The forced evaluation removes side effects from expressions, which
12429 -- should occur also in GNATprove mode. Otherwise, we end up with
12430 -- unexpected insertions of actions at places where this is not
12431 -- supposed to occur, e.g. on default parameters of a call.
12433 if Expander_Active or GNATprove_Mode then
12434 Force_Evaluation (Low_Bound (R));
12435 Force_Evaluation (High_Bound (R));
12438 elsif Nkind (S) = N_Discriminant_Association then
12440 -- Syntactically valid in subtype indication
12442 Error_Msg_N ("invalid index constraint", S);
12443 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12446 -- Subtype_Mark case, no anonymous subtypes to construct
12451 if Is_Entity_Name (S) then
12452 if not Is_Type (Entity (S)) then
12453 Error_Msg_N ("expect subtype mark for index constraint", S);
12455 elsif Base_Type (Entity (S)) /= Base_Type (T) then
12456 Wrong_Type (S, Base_Type (T));
12458 -- Check error of subtype with predicate in index constraint
12461 Bad_Predicated_Subtype_Use
12462 ("subtype& has predicate, not allowed in index constraint",
12469 Error_Msg_N ("invalid index constraint", S);
12470 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12476 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
12478 Set_Etype (Def_Id, Base_Type (T));
12480 if Is_Modular_Integer_Type (T) then
12481 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12483 elsif Is_Integer_Type (T) then
12484 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12487 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12488 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12489 Set_First_Literal (Def_Id, First_Literal (T));
12492 Set_Size_Info (Def_Id, (T));
12493 Set_RM_Size (Def_Id, RM_Size (T));
12494 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12496 Set_Scalar_Range (Def_Id, R);
12498 Set_Etype (S, Def_Id);
12499 Set_Discrete_RM_Size (Def_Id);
12500 end Constrain_Index;
12502 -----------------------
12503 -- Constrain_Integer --
12504 -----------------------
12506 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
12507 T : constant Entity_Id := Entity (Subtype_Mark (S));
12508 C : constant Node_Id := Constraint (S);
12511 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12513 if Is_Modular_Integer_Type (T) then
12514 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12516 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12519 Set_Etype (Def_Id, Base_Type (T));
12520 Set_Size_Info (Def_Id, (T));
12521 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12522 Set_Discrete_RM_Size (Def_Id);
12523 end Constrain_Integer;
12525 ------------------------------
12526 -- Constrain_Ordinary_Fixed --
12527 ------------------------------
12529 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
12530 T : constant Entity_Id := Entity (Subtype_Mark (S));
12536 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
12537 Set_Etype (Def_Id, Base_Type (T));
12538 Set_Size_Info (Def_Id, (T));
12539 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12540 Set_Small_Value (Def_Id, Small_Value (T));
12542 -- Process the constraint
12544 C := Constraint (S);
12546 -- Delta constraint present
12548 if Nkind (C) = N_Delta_Constraint then
12550 Check_SPARK_Restriction ("delta constraint is not allowed", S);
12551 Check_Restriction (No_Obsolescent_Features, C);
12553 if Warn_On_Obsolescent_Feature then
12555 ("subtype delta constraint is an " &
12556 "obsolescent feature (RM J.3(7))?j?");
12559 D := Delta_Expression (C);
12560 Analyze_And_Resolve (D, Any_Real);
12561 Check_Delta_Expression (D);
12562 Set_Delta_Value (Def_Id, Expr_Value_R (D));
12564 -- Check that delta value is in range. Obviously we can do this
12565 -- at compile time, but it is strictly a runtime check, and of
12566 -- course there is an ACVC test that checks this.
12568 if Delta_Value (Def_Id) < Delta_Value (T) then
12569 Error_Msg_N ("??delta value is too small", D);
12571 Make_Raise_Constraint_Error (Sloc (D),
12572 Reason => CE_Range_Check_Failed);
12573 Insert_Action (Declaration_Node (Def_Id), Rais);
12576 C := Range_Constraint (C);
12578 -- No delta constraint present
12581 Set_Delta_Value (Def_Id, Delta_Value (T));
12584 -- Range constraint present
12586 if Nkind (C) = N_Range_Constraint then
12587 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12589 -- No range constraint present
12592 pragma Assert (No (C));
12593 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12597 Set_Discrete_RM_Size (Def_Id);
12599 -- Unconditionally delay the freeze, since we cannot set size
12600 -- information in all cases correctly until the freeze point.
12602 Set_Has_Delayed_Freeze (Def_Id);
12603 end Constrain_Ordinary_Fixed;
12605 -----------------------
12606 -- Contain_Interface --
12607 -----------------------
12609 function Contain_Interface
12610 (Iface : Entity_Id;
12611 Ifaces : Elist_Id) return Boolean
12613 Iface_Elmt : Elmt_Id;
12616 if Present (Ifaces) then
12617 Iface_Elmt := First_Elmt (Ifaces);
12618 while Present (Iface_Elmt) loop
12619 if Node (Iface_Elmt) = Iface then
12623 Next_Elmt (Iface_Elmt);
12628 end Contain_Interface;
12630 ---------------------------
12631 -- Convert_Scalar_Bounds --
12632 ---------------------------
12634 procedure Convert_Scalar_Bounds
12636 Parent_Type : Entity_Id;
12637 Derived_Type : Entity_Id;
12640 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
12647 -- Defend against previous errors
12649 if No (Scalar_Range (Derived_Type)) then
12650 Check_Error_Detected;
12654 Lo := Build_Scalar_Bound
12655 (Type_Low_Bound (Derived_Type),
12656 Parent_Type, Implicit_Base);
12658 Hi := Build_Scalar_Bound
12659 (Type_High_Bound (Derived_Type),
12660 Parent_Type, Implicit_Base);
12667 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
12669 Set_Parent (Rng, N);
12670 Set_Scalar_Range (Derived_Type, Rng);
12672 -- Analyze the bounds
12674 Analyze_And_Resolve (Lo, Implicit_Base);
12675 Analyze_And_Resolve (Hi, Implicit_Base);
12677 -- Analyze the range itself, except that we do not analyze it if
12678 -- the bounds are real literals, and we have a fixed-point type.
12679 -- The reason for this is that we delay setting the bounds in this
12680 -- case till we know the final Small and Size values (see circuit
12681 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12683 if Is_Fixed_Point_Type (Parent_Type)
12684 and then Nkind (Lo) = N_Real_Literal
12685 and then Nkind (Hi) = N_Real_Literal
12689 -- Here we do the analysis of the range
12691 -- Note: we do this manually, since if we do a normal Analyze and
12692 -- Resolve call, there are problems with the conversions used for
12693 -- the derived type range.
12696 Set_Etype (Rng, Implicit_Base);
12697 Set_Analyzed (Rng, True);
12699 end Convert_Scalar_Bounds;
12701 -------------------
12702 -- Copy_And_Swap --
12703 -------------------
12705 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12707 -- Initialize new full declaration entity by copying the pertinent
12708 -- fields of the corresponding private declaration entity.
12710 -- We temporarily set Ekind to a value appropriate for a type to
12711 -- avoid assert failures in Einfo from checking for setting type
12712 -- attributes on something that is not a type. Ekind (Priv) is an
12713 -- appropriate choice, since it allowed the attributes to be set
12714 -- in the first place. This Ekind value will be modified later.
12716 Set_Ekind (Full, Ekind (Priv));
12718 -- Also set Etype temporarily to Any_Type, again, in the absence
12719 -- of errors, it will be properly reset, and if there are errors,
12720 -- then we want a value of Any_Type to remain.
12722 Set_Etype (Full, Any_Type);
12724 -- Now start copying attributes
12726 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12728 if Has_Discriminants (Full) then
12729 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12730 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12733 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12734 Set_Homonym (Full, Homonym (Priv));
12735 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12736 Set_Is_Public (Full, Is_Public (Priv));
12737 Set_Is_Pure (Full, Is_Pure (Priv));
12738 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12739 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12740 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12741 Set_Has_Pragma_Unreferenced_Objects
12742 (Full, Has_Pragma_Unreferenced_Objects
12745 Conditional_Delay (Full, Priv);
12747 if Is_Tagged_Type (Full) then
12748 Set_Direct_Primitive_Operations (Full,
12749 Direct_Primitive_Operations (Priv));
12751 if Is_Base_Type (Priv) then
12752 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12756 Set_Is_Volatile (Full, Is_Volatile (Priv));
12757 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12758 Set_Scope (Full, Scope (Priv));
12759 Set_Next_Entity (Full, Next_Entity (Priv));
12760 Set_First_Entity (Full, First_Entity (Priv));
12761 Set_Last_Entity (Full, Last_Entity (Priv));
12763 -- If access types have been recorded for later handling, keep them in
12764 -- the full view so that they get handled when the full view freeze
12765 -- node is expanded.
12767 if Present (Freeze_Node (Priv))
12768 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12770 Ensure_Freeze_Node (Full);
12771 Set_Access_Types_To_Process
12772 (Freeze_Node (Full),
12773 Access_Types_To_Process (Freeze_Node (Priv)));
12776 -- Swap the two entities. Now Private is the full type entity and Full
12777 -- is the private one. They will be swapped back at the end of the
12778 -- private part. This swapping ensures that the entity that is visible
12779 -- in the private part is the full declaration.
12781 Exchange_Entities (Priv, Full);
12782 Append_Entity (Full, Scope (Full));
12785 -------------------------------------
12786 -- Copy_Array_Base_Type_Attributes --
12787 -------------------------------------
12789 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12791 Set_Component_Alignment (T1, Component_Alignment (T2));
12792 Set_Component_Type (T1, Component_Type (T2));
12793 Set_Component_Size (T1, Component_Size (T2));
12794 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12795 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12796 Set_Has_Protected (T1, Has_Protected (T2));
12797 Set_Has_Task (T1, Has_Task (T2));
12798 Set_Is_Packed (T1, Is_Packed (T2));
12799 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12800 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12801 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12802 end Copy_Array_Base_Type_Attributes;
12804 -----------------------------------
12805 -- Copy_Array_Subtype_Attributes --
12806 -----------------------------------
12808 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12810 Set_Size_Info (T1, T2);
12812 Set_First_Index (T1, First_Index (T2));
12813 Set_Is_Aliased (T1, Is_Aliased (T2));
12814 Set_Is_Volatile (T1, Is_Volatile (T2));
12815 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12816 Set_Is_Constrained (T1, Is_Constrained (T2));
12817 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12818 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12819 Set_Convention (T1, Convention (T2));
12820 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12821 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12822 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
12823 end Copy_Array_Subtype_Attributes;
12825 -----------------------------------
12826 -- Create_Constrained_Components --
12827 -----------------------------------
12829 procedure Create_Constrained_Components
12831 Decl_Node : Node_Id;
12833 Constraints : Elist_Id)
12835 Loc : constant Source_Ptr := Sloc (Subt);
12836 Comp_List : constant Elist_Id := New_Elmt_List;
12837 Parent_Type : constant Entity_Id := Etype (Typ);
12838 Assoc_List : constant List_Id := New_List;
12839 Discr_Val : Elmt_Id;
12843 Is_Static : Boolean := True;
12845 procedure Collect_Fixed_Components (Typ : Entity_Id);
12846 -- Collect parent type components that do not appear in a variant part
12848 procedure Create_All_Components;
12849 -- Iterate over Comp_List to create the components of the subtype
12851 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12852 -- Creates a new component from Old_Compon, copying all the fields from
12853 -- it, including its Etype, inserts the new component in the Subt entity
12854 -- chain and returns the new component.
12856 function Is_Variant_Record (T : Entity_Id) return Boolean;
12857 -- If true, and discriminants are static, collect only components from
12858 -- variants selected by discriminant values.
12860 ------------------------------
12861 -- Collect_Fixed_Components --
12862 ------------------------------
12864 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12866 -- Build association list for discriminants, and find components of the
12867 -- variant part selected by the values of the discriminants.
12869 Old_C := First_Discriminant (Typ);
12870 Discr_Val := First_Elmt (Constraints);
12871 while Present (Old_C) loop
12872 Append_To (Assoc_List,
12873 Make_Component_Association (Loc,
12874 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12875 Expression => New_Copy (Node (Discr_Val))));
12877 Next_Elmt (Discr_Val);
12878 Next_Discriminant (Old_C);
12881 -- The tag and the possible parent component are unconditionally in
12884 if Is_Tagged_Type (Typ)
12885 or else Has_Controlled_Component (Typ)
12887 Old_C := First_Component (Typ);
12888 while Present (Old_C) loop
12889 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
12890 Append_Elmt (Old_C, Comp_List);
12893 Next_Component (Old_C);
12896 end Collect_Fixed_Components;
12898 ---------------------------
12899 -- Create_All_Components --
12900 ---------------------------
12902 procedure Create_All_Components is
12906 Comp := First_Elmt (Comp_List);
12907 while Present (Comp) loop
12908 Old_C := Node (Comp);
12909 New_C := Create_Component (Old_C);
12913 Constrain_Component_Type
12914 (Old_C, Subt, Decl_Node, Typ, Constraints));
12915 Set_Is_Public (New_C, Is_Public (Subt));
12919 end Create_All_Components;
12921 ----------------------
12922 -- Create_Component --
12923 ----------------------
12925 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12926 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12929 if Ekind (Old_Compon) = E_Discriminant
12930 and then Is_Completely_Hidden (Old_Compon)
12932 -- This is a shadow discriminant created for a discriminant of
12933 -- the parent type, which needs to be present in the subtype.
12934 -- Give the shadow discriminant an internal name that cannot
12935 -- conflict with that of visible components.
12937 Set_Chars (New_Compon, New_Internal_Name ('C'));
12940 -- Set the parent so we have a proper link for freezing etc. This is
12941 -- not a real parent pointer, since of course our parent does not own
12942 -- up to us and reference us, we are an illegitimate child of the
12943 -- original parent.
12945 Set_Parent (New_Compon, Parent (Old_Compon));
12947 -- If the old component's Esize was already determined and is a
12948 -- static value, then the new component simply inherits it. Otherwise
12949 -- the old component's size may require run-time determination, but
12950 -- the new component's size still might be statically determinable
12951 -- (if, for example it has a static constraint). In that case we want
12952 -- Layout_Type to recompute the component's size, so we reset its
12953 -- size and positional fields.
12955 if Frontend_Layout_On_Target
12956 and then not Known_Static_Esize (Old_Compon)
12958 Set_Esize (New_Compon, Uint_0);
12959 Init_Normalized_First_Bit (New_Compon);
12960 Init_Normalized_Position (New_Compon);
12961 Init_Normalized_Position_Max (New_Compon);
12964 -- We do not want this node marked as Comes_From_Source, since
12965 -- otherwise it would get first class status and a separate cross-
12966 -- reference line would be generated. Illegitimate children do not
12967 -- rate such recognition.
12969 Set_Comes_From_Source (New_Compon, False);
12971 -- But it is a real entity, and a birth certificate must be properly
12972 -- registered by entering it into the entity list.
12974 Enter_Name (New_Compon);
12977 end Create_Component;
12979 -----------------------
12980 -- Is_Variant_Record --
12981 -----------------------
12983 function Is_Variant_Record (T : Entity_Id) return Boolean is
12985 return Nkind (Parent (T)) = N_Full_Type_Declaration
12986 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12987 and then Present (Component_List (Type_Definition (Parent (T))))
12990 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12991 end Is_Variant_Record;
12993 -- Start of processing for Create_Constrained_Components
12996 pragma Assert (Subt /= Base_Type (Subt));
12997 pragma Assert (Typ = Base_Type (Typ));
12999 Set_First_Entity (Subt, Empty);
13000 Set_Last_Entity (Subt, Empty);
13002 -- Check whether constraint is fully static, in which case we can
13003 -- optimize the list of components.
13005 Discr_Val := First_Elmt (Constraints);
13006 while Present (Discr_Val) loop
13007 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13008 Is_Static := False;
13012 Next_Elmt (Discr_Val);
13015 Set_Has_Static_Discriminants (Subt, Is_Static);
13019 -- Inherit the discriminants of the parent type
13021 Add_Discriminants : declare
13027 Old_C := First_Discriminant (Typ);
13029 while Present (Old_C) loop
13030 Num_Disc := Num_Disc + 1;
13031 New_C := Create_Component (Old_C);
13032 Set_Is_Public (New_C, Is_Public (Subt));
13033 Next_Discriminant (Old_C);
13036 -- For an untagged derived subtype, the number of discriminants may
13037 -- be smaller than the number of inherited discriminants, because
13038 -- several of them may be renamed by a single new discriminant or
13039 -- constrained. In this case, add the hidden discriminants back into
13040 -- the subtype, because they need to be present if the optimizer of
13041 -- the GCC 4.x back-end decides to break apart assignments between
13042 -- objects using the parent view into member-wise assignments.
13046 if Is_Derived_Type (Typ)
13047 and then not Is_Tagged_Type (Typ)
13049 Old_C := First_Stored_Discriminant (Typ);
13051 while Present (Old_C) loop
13052 Num_Gird := Num_Gird + 1;
13053 Next_Stored_Discriminant (Old_C);
13057 if Num_Gird > Num_Disc then
13059 -- Find out multiple uses of new discriminants, and add hidden
13060 -- components for the extra renamed discriminants. We recognize
13061 -- multiple uses through the Corresponding_Discriminant of a
13062 -- new discriminant: if it constrains several old discriminants,
13063 -- this field points to the last one in the parent type. The
13064 -- stored discriminants of the derived type have the same name
13065 -- as those of the parent.
13069 New_Discr : Entity_Id;
13070 Old_Discr : Entity_Id;
13073 Constr := First_Elmt (Stored_Constraint (Typ));
13074 Old_Discr := First_Stored_Discriminant (Typ);
13075 while Present (Constr) loop
13076 if Is_Entity_Name (Node (Constr))
13077 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13079 New_Discr := Entity (Node (Constr));
13081 if Chars (Corresponding_Discriminant (New_Discr)) /=
13084 -- The new discriminant has been used to rename a
13085 -- subsequent old discriminant. Introduce a shadow
13086 -- component for the current old discriminant.
13088 New_C := Create_Component (Old_Discr);
13089 Set_Original_Record_Component (New_C, Old_Discr);
13093 -- The constraint has eliminated the old discriminant.
13094 -- Introduce a shadow component.
13096 New_C := Create_Component (Old_Discr);
13097 Set_Original_Record_Component (New_C, Old_Discr);
13100 Next_Elmt (Constr);
13101 Next_Stored_Discriminant (Old_Discr);
13105 end Add_Discriminants;
13108 and then Is_Variant_Record (Typ)
13110 Collect_Fixed_Components (Typ);
13112 Gather_Components (
13114 Component_List (Type_Definition (Parent (Typ))),
13115 Governed_By => Assoc_List,
13117 Report_Errors => Errors);
13118 pragma Assert (not Errors);
13120 Create_All_Components;
13122 -- If the subtype declaration is created for a tagged type derivation
13123 -- with constraints, we retrieve the record definition of the parent
13124 -- type to select the components of the proper variant.
13127 and then Is_Tagged_Type (Typ)
13128 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13130 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13131 and then Is_Variant_Record (Parent_Type)
13133 Collect_Fixed_Components (Typ);
13135 Gather_Components (
13137 Component_List (Type_Definition (Parent (Parent_Type))),
13138 Governed_By => Assoc_List,
13140 Report_Errors => Errors);
13141 pragma Assert (not Errors);
13143 -- If the tagged derivation has a type extension, collect all the
13144 -- new components therein.
13147 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13149 Old_C := First_Component (Typ);
13150 while Present (Old_C) loop
13151 if Original_Record_Component (Old_C) = Old_C
13152 and then Chars (Old_C) /= Name_uTag
13153 and then Chars (Old_C) /= Name_uParent
13155 Append_Elmt (Old_C, Comp_List);
13158 Next_Component (Old_C);
13162 Create_All_Components;
13165 -- If discriminants are not static, or if this is a multi-level type
13166 -- extension, we have to include all components of the parent type.
13168 Old_C := First_Component (Typ);
13169 while Present (Old_C) loop
13170 New_C := Create_Component (Old_C);
13174 Constrain_Component_Type
13175 (Old_C, Subt, Decl_Node, Typ, Constraints));
13176 Set_Is_Public (New_C, Is_Public (Subt));
13178 Next_Component (Old_C);
13183 end Create_Constrained_Components;
13185 ------------------------------------------
13186 -- Decimal_Fixed_Point_Type_Declaration --
13187 ------------------------------------------
13189 procedure Decimal_Fixed_Point_Type_Declaration
13193 Loc : constant Source_Ptr := Sloc (Def);
13194 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13195 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13196 Implicit_Base : Entity_Id;
13203 Check_SPARK_Restriction
13204 ("decimal fixed point type is not allowed", Def);
13205 Check_Restriction (No_Fixed_Point, Def);
13207 -- Create implicit base type
13210 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13211 Set_Etype (Implicit_Base, Implicit_Base);
13213 -- Analyze and process delta expression
13215 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13217 Check_Delta_Expression (Delta_Expr);
13218 Delta_Val := Expr_Value_R (Delta_Expr);
13220 -- Check delta is power of 10, and determine scale value from it
13226 Scale_Val := Uint_0;
13229 if Val < Ureal_1 then
13230 while Val < Ureal_1 loop
13231 Val := Val * Ureal_10;
13232 Scale_Val := Scale_Val + 1;
13235 if Scale_Val > 18 then
13236 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13237 Scale_Val := UI_From_Int (+18);
13241 while Val > Ureal_1 loop
13242 Val := Val / Ureal_10;
13243 Scale_Val := Scale_Val - 1;
13246 if Scale_Val < -18 then
13247 Error_Msg_N ("scale is less than minimum value of -18", Def);
13248 Scale_Val := UI_From_Int (-18);
13252 if Val /= Ureal_1 then
13253 Error_Msg_N ("delta expression must be a power of 10", Def);
13254 Delta_Val := Ureal_10 ** (-Scale_Val);
13258 -- Set delta, scale and small (small = delta for decimal type)
13260 Set_Delta_Value (Implicit_Base, Delta_Val);
13261 Set_Scale_Value (Implicit_Base, Scale_Val);
13262 Set_Small_Value (Implicit_Base, Delta_Val);
13264 -- Analyze and process digits expression
13266 Analyze_And_Resolve (Digs_Expr, Any_Integer);
13267 Check_Digits_Expression (Digs_Expr);
13268 Digs_Val := Expr_Value (Digs_Expr);
13270 if Digs_Val > 18 then
13271 Digs_Val := UI_From_Int (+18);
13272 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
13275 Set_Digits_Value (Implicit_Base, Digs_Val);
13276 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
13278 -- Set range of base type from digits value for now. This will be
13279 -- expanded to represent the true underlying base range by Freeze.
13281 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
13283 -- Note: We leave size as zero for now, size will be set at freeze
13284 -- time. We have to do this for ordinary fixed-point, because the size
13285 -- depends on the specified small, and we might as well do the same for
13286 -- decimal fixed-point.
13288 pragma Assert (Esize (Implicit_Base) = Uint_0);
13290 -- If there are bounds given in the declaration use them as the
13291 -- bounds of the first named subtype.
13293 if Present (Real_Range_Specification (Def)) then
13295 RRS : constant Node_Id := Real_Range_Specification (Def);
13296 Low : constant Node_Id := Low_Bound (RRS);
13297 High : constant Node_Id := High_Bound (RRS);
13302 Analyze_And_Resolve (Low, Any_Real);
13303 Analyze_And_Resolve (High, Any_Real);
13304 Check_Real_Bound (Low);
13305 Check_Real_Bound (High);
13306 Low_Val := Expr_Value_R (Low);
13307 High_Val := Expr_Value_R (High);
13309 if Low_Val < (-Bound_Val) then
13311 ("range low bound too small for digits value", Low);
13312 Low_Val := -Bound_Val;
13315 if High_Val > Bound_Val then
13317 ("range high bound too large for digits value", High);
13318 High_Val := Bound_Val;
13321 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
13324 -- If no explicit range, use range that corresponds to given
13325 -- digits value. This will end up as the final range for the
13329 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
13332 -- Complete entity for first subtype
13334 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
13335 Set_Etype (T, Implicit_Base);
13336 Set_Size_Info (T, Implicit_Base);
13337 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
13338 Set_Digits_Value (T, Digs_Val);
13339 Set_Delta_Value (T, Delta_Val);
13340 Set_Small_Value (T, Delta_Val);
13341 Set_Scale_Value (T, Scale_Val);
13342 Set_Is_Constrained (T);
13343 end Decimal_Fixed_Point_Type_Declaration;
13345 -----------------------------------
13346 -- Derive_Progenitor_Subprograms --
13347 -----------------------------------
13349 procedure Derive_Progenitor_Subprograms
13350 (Parent_Type : Entity_Id;
13351 Tagged_Type : Entity_Id)
13356 Iface_Elmt : Elmt_Id;
13357 Iface_Subp : Entity_Id;
13358 New_Subp : Entity_Id := Empty;
13359 Prim_Elmt : Elmt_Id;
13364 pragma Assert (Ada_Version >= Ada_2005
13365 and then Is_Record_Type (Tagged_Type)
13366 and then Is_Tagged_Type (Tagged_Type)
13367 and then Has_Interfaces (Tagged_Type));
13369 -- Step 1: Transfer to the full-view primitives associated with the
13370 -- partial-view that cover interface primitives. Conceptually this
13371 -- work should be done later by Process_Full_View; done here to
13372 -- simplify its implementation at later stages. It can be safely
13373 -- done here because interfaces must be visible in the partial and
13374 -- private view (RM 7.3(7.3/2)).
13376 -- Small optimization: This work is only required if the parent may
13377 -- have entities whose Alias attribute reference an interface primitive.
13378 -- Such a situation may occur if the parent is an abstract type and the
13379 -- primitive has not been yet overridden or if the parent is a generic
13380 -- formal type covering interfaces.
13382 -- If the tagged type is not abstract, it cannot have abstract
13383 -- primitives (the only entities in the list of primitives of
13384 -- non-abstract tagged types that can reference abstract primitives
13385 -- through its Alias attribute are the internal entities that have
13386 -- attribute Interface_Alias, and these entities are generated later
13387 -- by Add_Internal_Interface_Entities).
13389 if In_Private_Part (Current_Scope)
13390 and then (Is_Abstract_Type (Parent_Type)
13392 Is_Generic_Type (Parent_Type))
13394 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
13395 while Present (Elmt) loop
13396 Subp := Node (Elmt);
13398 -- At this stage it is not possible to have entities in the list
13399 -- of primitives that have attribute Interface_Alias.
13401 pragma Assert (No (Interface_Alias (Subp)));
13403 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
13405 if Is_Interface (Typ) then
13406 E := Find_Primitive_Covering_Interface
13407 (Tagged_Type => Tagged_Type,
13408 Iface_Prim => Subp);
13411 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
13413 Replace_Elmt (Elmt, E);
13414 Remove_Homonym (Subp);
13422 -- Step 2: Add primitives of progenitors that are not implemented by
13423 -- parents of Tagged_Type.
13425 if Present (Interfaces (Base_Type (Tagged_Type))) then
13426 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
13427 while Present (Iface_Elmt) loop
13428 Iface := Node (Iface_Elmt);
13430 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
13431 while Present (Prim_Elmt) loop
13432 Iface_Subp := Node (Prim_Elmt);
13434 -- Exclude derivation of predefined primitives except those
13435 -- that come from source, or are inherited from one that comes
13436 -- from source. Required to catch declarations of equality
13437 -- operators of interfaces. For example:
13439 -- type Iface is interface;
13440 -- function "=" (Left, Right : Iface) return Boolean;
13442 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
13443 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
13445 E := Find_Primitive_Covering_Interface
13446 (Tagged_Type => Tagged_Type,
13447 Iface_Prim => Iface_Subp);
13449 -- If not found we derive a new primitive leaving its alias
13450 -- attribute referencing the interface primitive.
13454 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13456 -- Ada 2012 (AI05-0197): If the covering primitive's name
13457 -- differs from the name of the interface primitive then it
13458 -- is a private primitive inherited from a parent type. In
13459 -- such case, given that Tagged_Type covers the interface,
13460 -- the inherited private primitive becomes visible. For such
13461 -- purpose we add a new entity that renames the inherited
13462 -- private primitive.
13464 elsif Chars (E) /= Chars (Iface_Subp) then
13465 pragma Assert (Has_Suffix (E, 'P'));
13467 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13468 Set_Alias (New_Subp, E);
13469 Set_Is_Abstract_Subprogram (New_Subp,
13470 Is_Abstract_Subprogram (E));
13472 -- Propagate to the full view interface entities associated
13473 -- with the partial view.
13475 elsif In_Private_Part (Current_Scope)
13476 and then Present (Alias (E))
13477 and then Alias (E) = Iface_Subp
13479 List_Containing (Parent (E)) /=
13480 Private_Declarations
13482 (Unit_Declaration_Node (Current_Scope)))
13484 Append_Elmt (E, Primitive_Operations (Tagged_Type));
13488 Next_Elmt (Prim_Elmt);
13491 Next_Elmt (Iface_Elmt);
13494 end Derive_Progenitor_Subprograms;
13496 -----------------------
13497 -- Derive_Subprogram --
13498 -----------------------
13500 procedure Derive_Subprogram
13501 (New_Subp : in out Entity_Id;
13502 Parent_Subp : Entity_Id;
13503 Derived_Type : Entity_Id;
13504 Parent_Type : Entity_Id;
13505 Actual_Subp : Entity_Id := Empty)
13507 Formal : Entity_Id;
13508 -- Formal parameter of parent primitive operation
13510 Formal_Of_Actual : Entity_Id;
13511 -- Formal parameter of actual operation, when the derivation is to
13512 -- create a renaming for a primitive operation of an actual in an
13515 New_Formal : Entity_Id;
13516 -- Formal of inherited operation
13518 Visible_Subp : Entity_Id := Parent_Subp;
13520 function Is_Private_Overriding return Boolean;
13521 -- If Subp is a private overriding of a visible operation, the inherited
13522 -- operation derives from the overridden op (even though its body is the
13523 -- overriding one) and the inherited operation is visible now. See
13524 -- sem_disp to see the full details of the handling of the overridden
13525 -- subprogram, which is removed from the list of primitive operations of
13526 -- the type. The overridden subprogram is saved locally in Visible_Subp,
13527 -- and used to diagnose abstract operations that need overriding in the
13530 procedure Replace_Type (Id, New_Id : Entity_Id);
13531 -- When the type is an anonymous access type, create a new access type
13532 -- designating the derived type.
13534 procedure Set_Derived_Name;
13535 -- This procedure sets the appropriate Chars name for New_Subp. This
13536 -- is normally just a copy of the parent name. An exception arises for
13537 -- type support subprograms, where the name is changed to reflect the
13538 -- name of the derived type, e.g. if type foo is derived from type bar,
13539 -- then a procedure barDA is derived with a name fooDA.
13541 ---------------------------
13542 -- Is_Private_Overriding --
13543 ---------------------------
13545 function Is_Private_Overriding return Boolean is
13549 -- If the parent is not a dispatching operation there is no
13550 -- need to investigate overridings
13552 if not Is_Dispatching_Operation (Parent_Subp) then
13556 -- The visible operation that is overridden is a homonym of the
13557 -- parent subprogram. We scan the homonym chain to find the one
13558 -- whose alias is the subprogram we are deriving.
13560 Prev := Current_Entity (Parent_Subp);
13561 while Present (Prev) loop
13562 if Ekind (Prev) = Ekind (Parent_Subp)
13563 and then Alias (Prev) = Parent_Subp
13564 and then Scope (Parent_Subp) = Scope (Prev)
13565 and then not Is_Hidden (Prev)
13567 Visible_Subp := Prev;
13571 Prev := Homonym (Prev);
13575 end Is_Private_Overriding;
13581 procedure Replace_Type (Id, New_Id : Entity_Id) is
13582 Id_Type : constant Entity_Id := Etype (Id);
13583 Acc_Type : Entity_Id;
13584 Par : constant Node_Id := Parent (Derived_Type);
13587 -- When the type is an anonymous access type, create a new access
13588 -- type designating the derived type. This itype must be elaborated
13589 -- at the point of the derivation, not on subsequent calls that may
13590 -- be out of the proper scope for Gigi, so we insert a reference to
13591 -- it after the derivation.
13593 if Ekind (Id_Type) = E_Anonymous_Access_Type then
13595 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
13598 if Ekind (Desig_Typ) = E_Record_Type_With_Private
13599 and then Present (Full_View (Desig_Typ))
13600 and then not Is_Private_Type (Parent_Type)
13602 Desig_Typ := Full_View (Desig_Typ);
13605 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
13607 -- Ada 2005 (AI-251): Handle also derivations of abstract
13608 -- interface primitives.
13610 or else (Is_Interface (Desig_Typ)
13611 and then not Is_Class_Wide_Type (Desig_Typ))
13613 Acc_Type := New_Copy (Id_Type);
13614 Set_Etype (Acc_Type, Acc_Type);
13615 Set_Scope (Acc_Type, New_Subp);
13617 -- Set size of anonymous access type. If we have an access
13618 -- to an unconstrained array, this is a fat pointer, so it
13619 -- is sizes at twice addtress size.
13621 if Is_Array_Type (Desig_Typ)
13622 and then not Is_Constrained (Desig_Typ)
13624 Init_Size (Acc_Type, 2 * System_Address_Size);
13626 -- Other cases use a thin pointer
13629 Init_Size (Acc_Type, System_Address_Size);
13632 -- Set remaining characterstics of anonymous access type
13634 Init_Alignment (Acc_Type);
13635 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
13637 Set_Etype (New_Id, Acc_Type);
13638 Set_Scope (New_Id, New_Subp);
13640 -- Create a reference to it
13642 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
13645 Set_Etype (New_Id, Id_Type);
13649 -- In Ada2012, a formal may have an incomplete type but the type
13650 -- derivation that inherits the primitive follows the full view.
13652 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
13654 (Ekind (Id_Type) = E_Record_Type_With_Private
13655 and then Present (Full_View (Id_Type))
13657 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
13659 (Ada_Version >= Ada_2012
13660 and then Ekind (Id_Type) = E_Incomplete_Type
13661 and then Full_View (Id_Type) = Parent_Type)
13663 -- Constraint checks on formals are generated during expansion,
13664 -- based on the signature of the original subprogram. The bounds
13665 -- of the derived type are not relevant, and thus we can use
13666 -- the base type for the formals. However, the return type may be
13667 -- used in a context that requires that the proper static bounds
13668 -- be used (a case statement, for example) and for those cases
13669 -- we must use the derived type (first subtype), not its base.
13671 -- If the derived_type_definition has no constraints, we know that
13672 -- the derived type has the same constraints as the first subtype
13673 -- of the parent, and we can also use it rather than its base,
13674 -- which can lead to more efficient code.
13676 if Etype (Id) = Parent_Type then
13677 if Is_Scalar_Type (Parent_Type)
13679 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
13681 Set_Etype (New_Id, Derived_Type);
13683 elsif Nkind (Par) = N_Full_Type_Declaration
13685 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
13688 (Subtype_Indication (Type_Definition (Par)))
13690 Set_Etype (New_Id, Derived_Type);
13693 Set_Etype (New_Id, Base_Type (Derived_Type));
13697 Set_Etype (New_Id, Base_Type (Derived_Type));
13701 Set_Etype (New_Id, Etype (Id));
13705 ----------------------
13706 -- Set_Derived_Name --
13707 ----------------------
13709 procedure Set_Derived_Name is
13710 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13712 if Nm = TSS_Null then
13713 Set_Chars (New_Subp, Chars (Parent_Subp));
13715 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13717 end Set_Derived_Name;
13719 -- Start of processing for Derive_Subprogram
13723 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13724 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13725 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
13727 -- Check whether the inherited subprogram is a private operation that
13728 -- should be inherited but not yet made visible. Such subprograms can
13729 -- become visible at a later point (e.g., the private part of a public
13730 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13731 -- following predicate is true, then this is not such a private
13732 -- operation and the subprogram simply inherits the name of the parent
13733 -- subprogram. Note the special check for the names of controlled
13734 -- operations, which are currently exempted from being inherited with
13735 -- a hidden name because they must be findable for generation of
13736 -- implicit run-time calls.
13738 if not Is_Hidden (Parent_Subp)
13739 or else Is_Internal (Parent_Subp)
13740 or else Is_Private_Overriding
13741 or else Is_Internal_Name (Chars (Parent_Subp))
13742 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
13748 -- An inherited dispatching equality will be overridden by an internally
13749 -- generated one, or by an explicit one, so preserve its name and thus
13750 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13751 -- private operation it may become invisible if the full view has
13752 -- progenitors, and the dispatch table will be malformed.
13753 -- We check that the type is limited to handle the anomalous declaration
13754 -- of Limited_Controlled, which is derived from a non-limited type, and
13755 -- which is handled specially elsewhere as well.
13757 elsif Chars (Parent_Subp) = Name_Op_Eq
13758 and then Is_Dispatching_Operation (Parent_Subp)
13759 and then Etype (Parent_Subp) = Standard_Boolean
13760 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13762 Etype (First_Formal (Parent_Subp)) =
13763 Etype (Next_Formal (First_Formal (Parent_Subp)))
13767 -- If parent is hidden, this can be a regular derivation if the
13768 -- parent is immediately visible in a non-instantiating context,
13769 -- or if we are in the private part of an instance. This test
13770 -- should still be refined ???
13772 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13773 -- operation as a non-visible operation in cases where the parent
13774 -- subprogram might not be visible now, but was visible within the
13775 -- original generic, so it would be wrong to make the inherited
13776 -- subprogram non-visible now. (Not clear if this test is fully
13777 -- correct; are there any cases where we should declare the inherited
13778 -- operation as not visible to avoid it being overridden, e.g., when
13779 -- the parent type is a generic actual with private primitives ???)
13781 -- (they should be treated the same as other private inherited
13782 -- subprograms, but it's not clear how to do this cleanly). ???
13784 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13785 and then Is_Immediately_Visible (Parent_Subp)
13786 and then not In_Instance)
13787 or else In_Instance_Not_Visible
13791 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13792 -- overrides an interface primitive because interface primitives
13793 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13795 elsif Ada_Version >= Ada_2005
13796 and then Is_Dispatching_Operation (Parent_Subp)
13797 and then Covers_Some_Interface (Parent_Subp)
13801 -- Otherwise, the type is inheriting a private operation, so enter
13802 -- it with a special name so it can't be overridden.
13805 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13808 Set_Parent (New_Subp, Parent (Derived_Type));
13810 if Present (Actual_Subp) then
13811 Replace_Type (Actual_Subp, New_Subp);
13813 Replace_Type (Parent_Subp, New_Subp);
13816 Conditional_Delay (New_Subp, Parent_Subp);
13818 -- If we are creating a renaming for a primitive operation of an
13819 -- actual of a generic derived type, we must examine the signature
13820 -- of the actual primitive, not that of the generic formal, which for
13821 -- example may be an interface. However the name and initial value
13822 -- of the inherited operation are those of the formal primitive.
13824 Formal := First_Formal (Parent_Subp);
13826 if Present (Actual_Subp) then
13827 Formal_Of_Actual := First_Formal (Actual_Subp);
13829 Formal_Of_Actual := Empty;
13832 while Present (Formal) loop
13833 New_Formal := New_Copy (Formal);
13835 -- Normally we do not go copying parents, but in the case of
13836 -- formals, we need to link up to the declaration (which is the
13837 -- parameter specification), and it is fine to link up to the
13838 -- original formal's parameter specification in this case.
13840 Set_Parent (New_Formal, Parent (Formal));
13841 Append_Entity (New_Formal, New_Subp);
13843 if Present (Formal_Of_Actual) then
13844 Replace_Type (Formal_Of_Actual, New_Formal);
13845 Next_Formal (Formal_Of_Actual);
13847 Replace_Type (Formal, New_Formal);
13850 Next_Formal (Formal);
13853 -- If this derivation corresponds to a tagged generic actual, then
13854 -- primitive operations rename those of the actual. Otherwise the
13855 -- primitive operations rename those of the parent type, If the parent
13856 -- renames an intrinsic operator, so does the new subprogram. We except
13857 -- concatenation, which is always properly typed, and does not get
13858 -- expanded as other intrinsic operations.
13860 if No (Actual_Subp) then
13861 if Is_Intrinsic_Subprogram (Parent_Subp) then
13862 Set_Is_Intrinsic_Subprogram (New_Subp);
13864 if Present (Alias (Parent_Subp))
13865 and then Chars (Parent_Subp) /= Name_Op_Concat
13867 Set_Alias (New_Subp, Alias (Parent_Subp));
13869 Set_Alias (New_Subp, Parent_Subp);
13873 Set_Alias (New_Subp, Parent_Subp);
13877 Set_Alias (New_Subp, Actual_Subp);
13880 -- Derived subprograms of a tagged type must inherit the convention
13881 -- of the parent subprogram (a requirement of AI-117). Derived
13882 -- subprograms of untagged types simply get convention Ada by default.
13884 -- If the derived type is a tagged generic formal type with unknown
13885 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
13887 -- However, if the type is derived from a generic formal, the further
13888 -- inherited subprogram has the convention of the non-generic ancestor.
13889 -- Otherwise there would be no way to override the operation.
13890 -- (This is subject to forthcoming ARG discussions).
13892 if Is_Tagged_Type (Derived_Type) then
13893 if Is_Generic_Type (Derived_Type)
13894 and then Has_Unknown_Discriminants (Derived_Type)
13896 Set_Convention (New_Subp, Convention_Intrinsic);
13899 if Is_Generic_Type (Parent_Type)
13900 and then Has_Unknown_Discriminants (Parent_Type)
13902 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
13904 Set_Convention (New_Subp, Convention (Parent_Subp));
13909 -- Predefined controlled operations retain their name even if the parent
13910 -- is hidden (see above), but they are not primitive operations if the
13911 -- ancestor is not visible, for example if the parent is a private
13912 -- extension completed with a controlled extension. Note that a full
13913 -- type that is controlled can break privacy: the flag Is_Controlled is
13914 -- set on both views of the type.
13916 if Is_Controlled (Parent_Type)
13917 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
13920 and then Is_Hidden (Parent_Subp)
13921 and then not Is_Visibly_Controlled (Parent_Type)
13923 Set_Is_Hidden (New_Subp);
13926 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13927 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13929 if Ekind (Parent_Subp) = E_Procedure then
13930 Set_Is_Valued_Procedure
13931 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13933 Set_Has_Controlling_Result
13934 (New_Subp, Has_Controlling_Result (Parent_Subp));
13937 -- No_Return must be inherited properly. If this is overridden in the
13938 -- case of a dispatching operation, then a check is made in Sem_Disp
13939 -- that the overriding operation is also No_Return (no such check is
13940 -- required for the case of non-dispatching operation.
13942 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13944 -- A derived function with a controlling result is abstract. If the
13945 -- Derived_Type is a nonabstract formal generic derived type, then
13946 -- inherited operations are not abstract: the required check is done at
13947 -- instantiation time. If the derivation is for a generic actual, the
13948 -- function is not abstract unless the actual is.
13950 if Is_Generic_Type (Derived_Type)
13951 and then not Is_Abstract_Type (Derived_Type)
13955 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13956 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13958 elsif Ada_Version >= Ada_2005
13959 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13960 or else (Is_Tagged_Type (Derived_Type)
13961 and then Etype (New_Subp) = Derived_Type
13962 and then not Is_Null_Extension (Derived_Type))
13963 or else (Is_Tagged_Type (Derived_Type)
13964 and then Ekind (Etype (New_Subp)) =
13965 E_Anonymous_Access_Type
13966 and then Designated_Type (Etype (New_Subp)) =
13968 and then not Is_Null_Extension (Derived_Type)))
13969 and then No (Actual_Subp)
13971 if not Is_Tagged_Type (Derived_Type)
13972 or else Is_Abstract_Type (Derived_Type)
13973 or else Is_Abstract_Subprogram (Alias (New_Subp))
13975 Set_Is_Abstract_Subprogram (New_Subp);
13977 Set_Requires_Overriding (New_Subp);
13980 elsif Ada_Version < Ada_2005
13981 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13982 or else (Is_Tagged_Type (Derived_Type)
13983 and then Etype (New_Subp) = Derived_Type
13984 and then No (Actual_Subp)))
13986 Set_Is_Abstract_Subprogram (New_Subp);
13988 -- AI05-0097 : an inherited operation that dispatches on result is
13989 -- abstract if the derived type is abstract, even if the parent type
13990 -- is concrete and the derived type is a null extension.
13992 elsif Has_Controlling_Result (Alias (New_Subp))
13993 and then Is_Abstract_Type (Etype (New_Subp))
13995 Set_Is_Abstract_Subprogram (New_Subp);
13997 -- Finally, if the parent type is abstract we must verify that all
13998 -- inherited operations are either non-abstract or overridden, or that
13999 -- the derived type itself is abstract (this check is performed at the
14000 -- end of a package declaration, in Check_Abstract_Overriding). A
14001 -- private overriding in the parent type will not be visible in the
14002 -- derivation if we are not in an inner package or in a child unit of
14003 -- the parent type, in which case the abstractness of the inherited
14004 -- operation is carried to the new subprogram.
14006 elsif Is_Abstract_Type (Parent_Type)
14007 and then not In_Open_Scopes (Scope (Parent_Type))
14008 and then Is_Private_Overriding
14009 and then Is_Abstract_Subprogram (Visible_Subp)
14011 if No (Actual_Subp) then
14012 Set_Alias (New_Subp, Visible_Subp);
14013 Set_Is_Abstract_Subprogram (New_Subp, True);
14016 -- If this is a derivation for an instance of a formal derived
14017 -- type, abstractness comes from the primitive operation of the
14018 -- actual, not from the operation inherited from the ancestor.
14020 Set_Is_Abstract_Subprogram
14021 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14025 New_Overloaded_Entity (New_Subp, Derived_Type);
14027 -- Check for case of a derived subprogram for the instantiation of a
14028 -- formal derived tagged type, if so mark the subprogram as dispatching
14029 -- and inherit the dispatching attributes of the actual subprogram. The
14030 -- derived subprogram is effectively renaming of the actual subprogram,
14031 -- so it needs to have the same attributes as the actual.
14033 if Present (Actual_Subp)
14034 and then Is_Dispatching_Operation (Actual_Subp)
14036 Set_Is_Dispatching_Operation (New_Subp);
14038 if Present (DTC_Entity (Actual_Subp)) then
14039 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14040 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
14044 -- Indicate that a derived subprogram does not require a body and that
14045 -- it does not require processing of default expressions.
14047 Set_Has_Completion (New_Subp);
14048 Set_Default_Expressions_Processed (New_Subp);
14050 if Ekind (New_Subp) = E_Function then
14051 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14053 end Derive_Subprogram;
14055 ------------------------
14056 -- Derive_Subprograms --
14057 ------------------------
14059 procedure Derive_Subprograms
14060 (Parent_Type : Entity_Id;
14061 Derived_Type : Entity_Id;
14062 Generic_Actual : Entity_Id := Empty)
14064 Op_List : constant Elist_Id :=
14065 Collect_Primitive_Operations (Parent_Type);
14067 function Check_Derived_Type return Boolean;
14068 -- Check that all the entities derived from Parent_Type are found in
14069 -- the list of primitives of Derived_Type exactly in the same order.
14071 procedure Derive_Interface_Subprogram
14072 (New_Subp : in out Entity_Id;
14074 Actual_Subp : Entity_Id);
14075 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14076 -- (which is an interface primitive). If Generic_Actual is present then
14077 -- Actual_Subp is the actual subprogram corresponding with the generic
14078 -- subprogram Subp.
14080 function Check_Derived_Type return Boolean is
14084 New_Subp : Entity_Id;
14089 -- Traverse list of entities in the current scope searching for
14090 -- an incomplete type whose full-view is derived type
14092 E := First_Entity (Scope (Derived_Type));
14093 while Present (E) and then E /= Derived_Type loop
14094 if Ekind (E) = E_Incomplete_Type
14095 and then Present (Full_View (E))
14096 and then Full_View (E) = Derived_Type
14098 -- Disable this test if Derived_Type completes an incomplete
14099 -- type because in such case more primitives can be added
14100 -- later to the list of primitives of Derived_Type by routine
14101 -- Process_Incomplete_Dependents
14106 E := Next_Entity (E);
14109 List := Collect_Primitive_Operations (Derived_Type);
14110 Elmt := First_Elmt (List);
14112 Op_Elmt := First_Elmt (Op_List);
14113 while Present (Op_Elmt) loop
14114 Subp := Node (Op_Elmt);
14115 New_Subp := Node (Elmt);
14117 -- At this early stage Derived_Type has no entities with attribute
14118 -- Interface_Alias. In addition, such primitives are always
14119 -- located at the end of the list of primitives of Parent_Type.
14120 -- Therefore, if found we can safely stop processing pending
14123 exit when Present (Interface_Alias (Subp));
14125 -- Handle hidden entities
14127 if not Is_Predefined_Dispatching_Operation (Subp)
14128 and then Is_Hidden (Subp)
14130 if Present (New_Subp)
14131 and then Primitive_Names_Match (Subp, New_Subp)
14137 if not Present (New_Subp)
14138 or else Ekind (Subp) /= Ekind (New_Subp)
14139 or else not Primitive_Names_Match (Subp, New_Subp)
14147 Next_Elmt (Op_Elmt);
14151 end Check_Derived_Type;
14153 ---------------------------------
14154 -- Derive_Interface_Subprogram --
14155 ---------------------------------
14157 procedure Derive_Interface_Subprogram
14158 (New_Subp : in out Entity_Id;
14160 Actual_Subp : Entity_Id)
14162 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14163 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14166 pragma Assert (Is_Interface (Iface_Type));
14169 (New_Subp => New_Subp,
14170 Parent_Subp => Iface_Subp,
14171 Derived_Type => Derived_Type,
14172 Parent_Type => Iface_Type,
14173 Actual_Subp => Actual_Subp);
14175 -- Given that this new interface entity corresponds with a primitive
14176 -- of the parent that was not overridden we must leave it associated
14177 -- with its parent primitive to ensure that it will share the same
14178 -- dispatch table slot when overridden.
14180 if No (Actual_Subp) then
14181 Set_Alias (New_Subp, Subp);
14183 -- For instantiations this is not needed since the previous call to
14184 -- Derive_Subprogram leaves the entity well decorated.
14187 pragma Assert (Alias (New_Subp) = Actual_Subp);
14190 end Derive_Interface_Subprogram;
14194 Alias_Subp : Entity_Id;
14195 Act_List : Elist_Id;
14196 Act_Elmt : Elmt_Id;
14197 Act_Subp : Entity_Id := Empty;
14199 Need_Search : Boolean := False;
14200 New_Subp : Entity_Id := Empty;
14201 Parent_Base : Entity_Id;
14204 -- Start of processing for Derive_Subprograms
14207 if Ekind (Parent_Type) = E_Record_Type_With_Private
14208 and then Has_Discriminants (Parent_Type)
14209 and then Present (Full_View (Parent_Type))
14211 Parent_Base := Full_View (Parent_Type);
14213 Parent_Base := Parent_Type;
14216 if Present (Generic_Actual) then
14217 Act_List := Collect_Primitive_Operations (Generic_Actual);
14218 Act_Elmt := First_Elmt (Act_List);
14220 Act_List := No_Elist;
14221 Act_Elmt := No_Elmt;
14224 -- Derive primitives inherited from the parent. Note that if the generic
14225 -- actual is present, this is not really a type derivation, it is a
14226 -- completion within an instance.
14228 -- Case 1: Derived_Type does not implement interfaces
14230 if not Is_Tagged_Type (Derived_Type)
14231 or else (not Has_Interfaces (Derived_Type)
14232 and then not (Present (Generic_Actual)
14233 and then Has_Interfaces (Generic_Actual)))
14235 Elmt := First_Elmt (Op_List);
14236 while Present (Elmt) loop
14237 Subp := Node (Elmt);
14239 -- Literals are derived earlier in the process of building the
14240 -- derived type, and are skipped here.
14242 if Ekind (Subp) = E_Enumeration_Literal then
14245 -- The actual is a direct descendant and the common primitive
14246 -- operations appear in the same order.
14248 -- If the generic parent type is present, the derived type is an
14249 -- instance of a formal derived type, and within the instance its
14250 -- operations are those of the actual. We derive from the formal
14251 -- type but make the inherited operations aliases of the
14252 -- corresponding operations of the actual.
14255 pragma Assert (No (Node (Act_Elmt))
14256 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
14259 (Subp, Node (Act_Elmt),
14260 Skip_Controlling_Formals => True)));
14263 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
14265 if Present (Act_Elmt) then
14266 Next_Elmt (Act_Elmt);
14273 -- Case 2: Derived_Type implements interfaces
14276 -- If the parent type has no predefined primitives we remove
14277 -- predefined primitives from the list of primitives of generic
14278 -- actual to simplify the complexity of this algorithm.
14280 if Present (Generic_Actual) then
14282 Has_Predefined_Primitives : Boolean := False;
14285 -- Check if the parent type has predefined primitives
14287 Elmt := First_Elmt (Op_List);
14288 while Present (Elmt) loop
14289 Subp := Node (Elmt);
14291 if Is_Predefined_Dispatching_Operation (Subp)
14292 and then not Comes_From_Source (Ultimate_Alias (Subp))
14294 Has_Predefined_Primitives := True;
14301 -- Remove predefined primitives of Generic_Actual. We must use
14302 -- an auxiliary list because in case of tagged types the value
14303 -- returned by Collect_Primitive_Operations is the value stored
14304 -- in its Primitive_Operations attribute (and we don't want to
14305 -- modify its current contents).
14307 if not Has_Predefined_Primitives then
14309 Aux_List : constant Elist_Id := New_Elmt_List;
14312 Elmt := First_Elmt (Act_List);
14313 while Present (Elmt) loop
14314 Subp := Node (Elmt);
14316 if not Is_Predefined_Dispatching_Operation (Subp)
14317 or else Comes_From_Source (Subp)
14319 Append_Elmt (Subp, Aux_List);
14325 Act_List := Aux_List;
14329 Act_Elmt := First_Elmt (Act_List);
14330 Act_Subp := Node (Act_Elmt);
14334 -- Stage 1: If the generic actual is not present we derive the
14335 -- primitives inherited from the parent type. If the generic parent
14336 -- type is present, the derived type is an instance of a formal
14337 -- derived type, and within the instance its operations are those of
14338 -- the actual. We derive from the formal type but make the inherited
14339 -- operations aliases of the corresponding operations of the actual.
14341 Elmt := First_Elmt (Op_List);
14342 while Present (Elmt) loop
14343 Subp := Node (Elmt);
14344 Alias_Subp := Ultimate_Alias (Subp);
14346 -- Do not derive internal entities of the parent that link
14347 -- interface primitives with their covering primitive. These
14348 -- entities will be added to this type when frozen.
14350 if Present (Interface_Alias (Subp)) then
14354 -- If the generic actual is present find the corresponding
14355 -- operation in the generic actual. If the parent type is a
14356 -- direct ancestor of the derived type then, even if it is an
14357 -- interface, the operations are inherited from the primary
14358 -- dispatch table and are in the proper order. If we detect here
14359 -- that primitives are not in the same order we traverse the list
14360 -- of primitive operations of the actual to find the one that
14361 -- implements the interface primitive.
14365 (Present (Generic_Actual)
14366 and then Present (Act_Subp)
14368 (Primitive_Names_Match (Subp, Act_Subp)
14370 Type_Conformant (Subp, Act_Subp,
14371 Skip_Controlling_Formals => True)))
14373 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
14374 Use_Full_View => True));
14376 -- Remember that we need searching for all pending primitives
14378 Need_Search := True;
14380 -- Handle entities associated with interface primitives
14382 if Present (Alias_Subp)
14383 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14384 and then not Is_Predefined_Dispatching_Operation (Subp)
14386 -- Search for the primitive in the homonym chain
14389 Find_Primitive_Covering_Interface
14390 (Tagged_Type => Generic_Actual,
14391 Iface_Prim => Alias_Subp);
14393 -- Previous search may not locate primitives covering
14394 -- interfaces defined in generics units or instantiations.
14395 -- (it fails if the covering primitive has formals whose
14396 -- type is also defined in generics or instantiations).
14397 -- In such case we search in the list of primitives of the
14398 -- generic actual for the internal entity that links the
14399 -- interface primitive and the covering primitive.
14402 and then Is_Generic_Type (Parent_Type)
14404 -- This code has been designed to handle only generic
14405 -- formals that implement interfaces that are defined
14406 -- in a generic unit or instantiation. If this code is
14407 -- needed for other cases we must review it because
14408 -- (given that it relies on Original_Location to locate
14409 -- the primitive of Generic_Actual that covers the
14410 -- interface) it could leave linked through attribute
14411 -- Alias entities of unrelated instantiations).
14415 (Scope (Find_Dispatching_Type (Alias_Subp)))
14417 Instantiation_Depth
14418 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
14421 Iface_Prim_Loc : constant Source_Ptr :=
14422 Original_Location (Sloc (Alias_Subp));
14429 First_Elmt (Primitive_Operations (Generic_Actual));
14431 Search : while Present (Elmt) loop
14432 Prim := Node (Elmt);
14434 if Present (Interface_Alias (Prim))
14435 and then Original_Location
14436 (Sloc (Interface_Alias (Prim))) =
14439 Act_Subp := Alias (Prim);
14448 pragma Assert (Present (Act_Subp)
14449 or else Is_Abstract_Type (Generic_Actual)
14450 or else Serious_Errors_Detected > 0);
14452 -- Handle predefined primitives plus the rest of user-defined
14456 Act_Elmt := First_Elmt (Act_List);
14457 while Present (Act_Elmt) loop
14458 Act_Subp := Node (Act_Elmt);
14460 exit when Primitive_Names_Match (Subp, Act_Subp)
14461 and then Type_Conformant
14463 Skip_Controlling_Formals => True)
14464 and then No (Interface_Alias (Act_Subp));
14466 Next_Elmt (Act_Elmt);
14469 if No (Act_Elmt) then
14475 -- Case 1: If the parent is a limited interface then it has the
14476 -- predefined primitives of synchronized interfaces. However, the
14477 -- actual type may be a non-limited type and hence it does not
14478 -- have such primitives.
14480 if Present (Generic_Actual)
14481 and then not Present (Act_Subp)
14482 and then Is_Limited_Interface (Parent_Base)
14483 and then Is_Predefined_Interface_Primitive (Subp)
14487 -- Case 2: Inherit entities associated with interfaces that were
14488 -- not covered by the parent type. We exclude here null interface
14489 -- primitives because they do not need special management.
14491 -- We also exclude interface operations that are renamings. If the
14492 -- subprogram is an explicit renaming of an interface primitive,
14493 -- it is a regular primitive operation, and the presence of its
14494 -- alias is not relevant: it has to be derived like any other
14497 elsif Present (Alias (Subp))
14498 and then Nkind (Unit_Declaration_Node (Subp)) /=
14499 N_Subprogram_Renaming_Declaration
14500 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14502 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
14503 and then Null_Present (Parent (Alias_Subp)))
14505 -- If this is an abstract private type then we transfer the
14506 -- derivation of the interface primitive from the partial view
14507 -- to the full view. This is safe because all the interfaces
14508 -- must be visible in the partial view. Done to avoid adding
14509 -- a new interface derivation to the private part of the
14510 -- enclosing package; otherwise this new derivation would be
14511 -- decorated as hidden when the analysis of the enclosing
14512 -- package completes.
14514 if Is_Abstract_Type (Derived_Type)
14515 and then In_Private_Part (Current_Scope)
14516 and then Has_Private_Declaration (Derived_Type)
14519 Partial_View : Entity_Id;
14524 Partial_View := First_Entity (Current_Scope);
14526 exit when No (Partial_View)
14527 or else (Has_Private_Declaration (Partial_View)
14529 Full_View (Partial_View) = Derived_Type);
14531 Next_Entity (Partial_View);
14534 -- If the partial view was not found then the source code
14535 -- has errors and the derivation is not needed.
14537 if Present (Partial_View) then
14539 First_Elmt (Primitive_Operations (Partial_View));
14540 while Present (Elmt) loop
14541 Ent := Node (Elmt);
14543 if Present (Alias (Ent))
14544 and then Ultimate_Alias (Ent) = Alias (Subp)
14547 (Ent, Primitive_Operations (Derived_Type));
14554 -- If the interface primitive was not found in the
14555 -- partial view then this interface primitive was
14556 -- overridden. We add a derivation to activate in
14557 -- Derive_Progenitor_Subprograms the machinery to
14561 Derive_Interface_Subprogram
14562 (New_Subp => New_Subp,
14564 Actual_Subp => Act_Subp);
14569 Derive_Interface_Subprogram
14570 (New_Subp => New_Subp,
14572 Actual_Subp => Act_Subp);
14575 -- Case 3: Common derivation
14579 (New_Subp => New_Subp,
14580 Parent_Subp => Subp,
14581 Derived_Type => Derived_Type,
14582 Parent_Type => Parent_Base,
14583 Actual_Subp => Act_Subp);
14586 -- No need to update Act_Elm if we must search for the
14587 -- corresponding operation in the generic actual
14590 and then Present (Act_Elmt)
14592 Next_Elmt (Act_Elmt);
14593 Act_Subp := Node (Act_Elmt);
14600 -- Inherit additional operations from progenitors. If the derived
14601 -- type is a generic actual, there are not new primitive operations
14602 -- for the type because it has those of the actual, and therefore
14603 -- nothing needs to be done. The renamings generated above are not
14604 -- primitive operations, and their purpose is simply to make the
14605 -- proper operations visible within an instantiation.
14607 if No (Generic_Actual) then
14608 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
14612 -- Final check: Direct descendants must have their primitives in the
14613 -- same order. We exclude from this test untagged types and instances
14614 -- of formal derived types. We skip this test if we have already
14615 -- reported serious errors in the sources.
14617 pragma Assert (not Is_Tagged_Type (Derived_Type)
14618 or else Present (Generic_Actual)
14619 or else Serious_Errors_Detected > 0
14620 or else Check_Derived_Type);
14621 end Derive_Subprograms;
14623 --------------------------------
14624 -- Derived_Standard_Character --
14625 --------------------------------
14627 procedure Derived_Standard_Character
14629 Parent_Type : Entity_Id;
14630 Derived_Type : Entity_Id)
14632 Loc : constant Source_Ptr := Sloc (N);
14633 Def : constant Node_Id := Type_Definition (N);
14634 Indic : constant Node_Id := Subtype_Indication (Def);
14635 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
14636 Implicit_Base : constant Entity_Id :=
14638 (E_Enumeration_Type, N, Derived_Type, 'B');
14644 Discard_Node (Process_Subtype (Indic, N));
14646 Set_Etype (Implicit_Base, Parent_Base);
14647 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
14648 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
14650 Set_Is_Character_Type (Implicit_Base, True);
14651 Set_Has_Delayed_Freeze (Implicit_Base);
14653 -- The bounds of the implicit base are the bounds of the parent base.
14654 -- Note that their type is the parent base.
14656 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
14657 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
14659 Set_Scalar_Range (Implicit_Base,
14662 High_Bound => Hi));
14664 Conditional_Delay (Derived_Type, Parent_Type);
14666 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
14667 Set_Etype (Derived_Type, Implicit_Base);
14668 Set_Size_Info (Derived_Type, Parent_Type);
14670 if Unknown_RM_Size (Derived_Type) then
14671 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
14674 Set_Is_Character_Type (Derived_Type, True);
14676 if Nkind (Indic) /= N_Subtype_Indication then
14678 -- If no explicit constraint, the bounds are those
14679 -- of the parent type.
14681 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
14682 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
14683 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
14686 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
14688 -- Because the implicit base is used in the conversion of the bounds, we
14689 -- have to freeze it now. This is similar to what is done for numeric
14690 -- types, and it equally suspicious, but otherwise a non-static bound
14691 -- will have a reference to an unfrozen type, which is rejected by Gigi
14692 -- (???). This requires specific care for definition of stream
14693 -- attributes. For details, see comments at the end of
14694 -- Build_Derived_Numeric_Type.
14696 Freeze_Before (N, Implicit_Base);
14697 end Derived_Standard_Character;
14699 ------------------------------
14700 -- Derived_Type_Declaration --
14701 ------------------------------
14703 procedure Derived_Type_Declaration
14706 Is_Completion : Boolean)
14708 Parent_Type : Entity_Id;
14710 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
14711 -- Check whether the parent type is a generic formal, or derives
14712 -- directly or indirectly from one.
14714 ------------------------
14715 -- Comes_From_Generic --
14716 ------------------------
14718 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
14720 if Is_Generic_Type (Typ) then
14723 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14726 elsif Is_Private_Type (Typ)
14727 and then Present (Full_View (Typ))
14728 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14732 elsif Is_Generic_Actual_Type (Typ) then
14738 end Comes_From_Generic;
14742 Def : constant Node_Id := Type_Definition (N);
14743 Iface_Def : Node_Id;
14744 Indic : constant Node_Id := Subtype_Indication (Def);
14745 Extension : constant Node_Id := Record_Extension_Part (Def);
14746 Parent_Node : Node_Id;
14749 -- Start of processing for Derived_Type_Declaration
14752 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14754 -- Ada 2005 (AI-251): In case of interface derivation check that the
14755 -- parent is also an interface.
14757 if Interface_Present (Def) then
14758 Check_SPARK_Restriction ("interface is not allowed", Def);
14760 if not Is_Interface (Parent_Type) then
14761 Diagnose_Interface (Indic, Parent_Type);
14764 Parent_Node := Parent (Base_Type (Parent_Type));
14765 Iface_Def := Type_Definition (Parent_Node);
14767 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14768 -- other limited interfaces.
14770 if Limited_Present (Def) then
14771 if Limited_Present (Iface_Def) then
14774 elsif Protected_Present (Iface_Def) then
14776 ("descendant of& must be declared"
14777 & " as a protected interface",
14780 elsif Synchronized_Present (Iface_Def) then
14782 ("descendant of& must be declared"
14783 & " as a synchronized interface",
14786 elsif Task_Present (Iface_Def) then
14788 ("descendant of& must be declared as a task interface",
14793 ("(Ada 2005) limited interface cannot "
14794 & "inherit from non-limited interface", Indic);
14797 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14798 -- from non-limited or limited interfaces.
14800 elsif not Protected_Present (Def)
14801 and then not Synchronized_Present (Def)
14802 and then not Task_Present (Def)
14804 if Limited_Present (Iface_Def) then
14807 elsif Protected_Present (Iface_Def) then
14809 ("descendant of& must be declared"
14810 & " as a protected interface",
14813 elsif Synchronized_Present (Iface_Def) then
14815 ("descendant of& must be declared"
14816 & " as a synchronized interface",
14819 elsif Task_Present (Iface_Def) then
14821 ("descendant of& must be declared as a task interface",
14830 if Is_Tagged_Type (Parent_Type)
14831 and then Is_Concurrent_Type (Parent_Type)
14832 and then not Is_Interface (Parent_Type)
14835 ("parent type of a record extension cannot be "
14836 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14837 Set_Etype (T, Any_Type);
14841 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14844 if Is_Tagged_Type (Parent_Type)
14845 and then Is_Non_Empty_List (Interface_List (Def))
14852 Intf := First (Interface_List (Def));
14853 while Present (Intf) loop
14854 T := Find_Type_Of_Subtype_Indic (Intf);
14856 if not Is_Interface (T) then
14857 Diagnose_Interface (Intf, T);
14859 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14860 -- a limited type from having a nonlimited progenitor.
14862 elsif (Limited_Present (Def)
14863 or else (not Is_Interface (Parent_Type)
14864 and then Is_Limited_Type (Parent_Type)))
14865 and then not Is_Limited_Interface (T)
14868 ("progenitor interface& of limited type must be limited",
14877 if Parent_Type = Any_Type
14878 or else Etype (Parent_Type) = Any_Type
14879 or else (Is_Class_Wide_Type (Parent_Type)
14880 and then Etype (Parent_Type) = T)
14882 -- If Parent_Type is undefined or illegal, make new type into a
14883 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14884 -- errors. If this is a self-definition, emit error now.
14887 or else T = Etype (Parent_Type)
14889 Error_Msg_N ("type cannot be used in its own definition", Indic);
14892 Set_Ekind (T, Ekind (Parent_Type));
14893 Set_Etype (T, Any_Type);
14894 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14896 if Is_Tagged_Type (T)
14897 and then Is_Record_Type (T)
14899 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14905 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14906 -- an interface is special because the list of interfaces in the full
14907 -- view can be given in any order. For example:
14909 -- type A is interface;
14910 -- type B is interface and A;
14911 -- type D is new B with private;
14913 -- type D is new A and B with null record; -- 1 --
14915 -- In this case we perform the following transformation of -1-:
14917 -- type D is new B and A with null record;
14919 -- If the parent of the full-view covers the parent of the partial-view
14920 -- we have two possible cases:
14922 -- 1) They have the same parent
14923 -- 2) The parent of the full-view implements some further interfaces
14925 -- In both cases we do not need to perform the transformation. In the
14926 -- first case the source program is correct and the transformation is
14927 -- not needed; in the second case the source program does not fulfill
14928 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14931 -- This transformation not only simplifies the rest of the analysis of
14932 -- this type declaration but also simplifies the correct generation of
14933 -- the object layout to the expander.
14935 if In_Private_Part (Current_Scope)
14936 and then Is_Interface (Parent_Type)
14940 Partial_View : Entity_Id;
14941 Partial_View_Parent : Entity_Id;
14942 New_Iface : Node_Id;
14945 -- Look for the associated private type declaration
14947 Partial_View := First_Entity (Current_Scope);
14949 exit when No (Partial_View)
14950 or else (Has_Private_Declaration (Partial_View)
14951 and then Full_View (Partial_View) = T);
14953 Next_Entity (Partial_View);
14956 -- If the partial view was not found then the source code has
14957 -- errors and the transformation is not needed.
14959 if Present (Partial_View) then
14960 Partial_View_Parent := Etype (Partial_View);
14962 -- If the parent of the full-view covers the parent of the
14963 -- partial-view we have nothing else to do.
14965 if Interface_Present_In_Ancestor
14966 (Parent_Type, Partial_View_Parent)
14970 -- Traverse the list of interfaces of the full-view to look
14971 -- for the parent of the partial-view and perform the tree
14975 Iface := First (Interface_List (Def));
14976 while Present (Iface) loop
14977 if Etype (Iface) = Etype (Partial_View) then
14978 Rewrite (Subtype_Indication (Def),
14979 New_Copy (Subtype_Indication
14980 (Parent (Partial_View))));
14983 Make_Identifier (Sloc (N), Chars (Parent_Type));
14984 Append (New_Iface, Interface_List (Def));
14986 -- Analyze the transformed code
14988 Derived_Type_Declaration (T, N, Is_Completion);
14999 -- Only composite types other than array types are allowed to have
15000 -- discriminants. In SPARK, no types are allowed to have discriminants.
15002 if Present (Discriminant_Specifications (N)) then
15003 if (Is_Elementary_Type (Parent_Type)
15004 or else Is_Array_Type (Parent_Type))
15005 and then not Error_Posted (N)
15008 ("elementary or array type cannot have discriminants",
15009 Defining_Identifier (First (Discriminant_Specifications (N))));
15010 Set_Has_Discriminants (T, False);
15012 Check_SPARK_Restriction ("discriminant type is not allowed", N);
15016 -- In Ada 83, a derived type defined in a package specification cannot
15017 -- be used for further derivation until the end of its visible part.
15018 -- Note that derivation in the private part of the package is allowed.
15020 if Ada_Version = Ada_83
15021 and then Is_Derived_Type (Parent_Type)
15022 and then In_Visible_Part (Scope (Parent_Type))
15024 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15026 ("(Ada 83): premature use of type for derivation", Indic);
15030 -- Check for early use of incomplete or private type
15032 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15033 Error_Msg_N ("premature derivation of incomplete type", Indic);
15036 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15037 and then not Comes_From_Generic (Parent_Type))
15038 or else Has_Private_Component (Parent_Type)
15040 -- The ancestor type of a formal type can be incomplete, in which
15041 -- case only the operations of the partial view are available in the
15042 -- generic. Subsequent checks may be required when the full view is
15043 -- analyzed to verify that a derivation from a tagged type has an
15046 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15049 elsif No (Underlying_Type (Parent_Type))
15050 or else Has_Private_Component (Parent_Type)
15053 ("premature derivation of derived or private type", Indic);
15055 -- Flag the type itself as being in error, this prevents some
15056 -- nasty problems with subsequent uses of the malformed type.
15058 Set_Error_Posted (T);
15060 -- Check that within the immediate scope of an untagged partial
15061 -- view it's illegal to derive from the partial view if the
15062 -- full view is tagged. (7.3(7))
15064 -- We verify that the Parent_Type is a partial view by checking
15065 -- that it is not a Full_Type_Declaration (i.e. a private type or
15066 -- private extension declaration), to distinguish a partial view
15067 -- from a derivation from a private type which also appears as
15068 -- E_Private_Type. If the parent base type is not declared in an
15069 -- enclosing scope there is no need to check.
15071 elsif Present (Full_View (Parent_Type))
15072 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15073 and then not Is_Tagged_Type (Parent_Type)
15074 and then Is_Tagged_Type (Full_View (Parent_Type))
15075 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15078 ("premature derivation from type with tagged full view",
15083 -- Check that form of derivation is appropriate
15085 Taggd := Is_Tagged_Type (Parent_Type);
15087 -- Perhaps the parent type should be changed to the class-wide type's
15088 -- specific type in this case to prevent cascading errors ???
15090 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15091 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15095 if Present (Extension) and then not Taggd then
15097 ("type derived from untagged type cannot have extension", Indic);
15099 elsif No (Extension) and then Taggd then
15101 -- If this declaration is within a private part (or body) of a
15102 -- generic instantiation then the derivation is allowed (the parent
15103 -- type can only appear tagged in this case if it's a generic actual
15104 -- type, since it would otherwise have been rejected in the analysis
15105 -- of the generic template).
15107 if not Is_Generic_Actual_Type (Parent_Type)
15108 or else In_Visible_Part (Scope (Parent_Type))
15110 if Is_Class_Wide_Type (Parent_Type) then
15112 ("parent type must not be a class-wide type", Indic);
15114 -- Use specific type to prevent cascaded errors.
15116 Parent_Type := Etype (Parent_Type);
15120 ("type derived from tagged type must have extension", Indic);
15125 -- AI-443: Synchronized formal derived types require a private
15126 -- extension. There is no point in checking the ancestor type or
15127 -- the progenitors since the construct is wrong to begin with.
15129 if Ada_Version >= Ada_2005
15130 and then Is_Generic_Type (T)
15131 and then Present (Original_Node (N))
15134 Decl : constant Node_Id := Original_Node (N);
15137 if Nkind (Decl) = N_Formal_Type_Declaration
15138 and then Nkind (Formal_Type_Definition (Decl)) =
15139 N_Formal_Derived_Type_Definition
15140 and then Synchronized_Present (Formal_Type_Definition (Decl))
15141 and then No (Extension)
15143 -- Avoid emitting a duplicate error message
15145 and then not Error_Posted (Indic)
15148 ("synchronized derived type must have extension", N);
15153 if Null_Exclusion_Present (Def)
15154 and then not Is_Access_Type (Parent_Type)
15156 Error_Msg_N ("null exclusion can only apply to an access type", N);
15159 -- Avoid deriving parent primitives of underlying record views
15161 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15162 Derive_Subps => not Is_Underlying_Record_View (T));
15164 -- AI-419: The parent type of an explicitly limited derived type must
15165 -- be a limited type or a limited interface.
15167 if Limited_Present (Def) then
15168 Set_Is_Limited_Record (T);
15170 if Is_Interface (T) then
15171 Set_Is_Limited_Interface (T);
15174 if not Is_Limited_Type (Parent_Type)
15176 (not Is_Interface (Parent_Type)
15177 or else not Is_Limited_Interface (Parent_Type))
15179 -- AI05-0096: a derivation in the private part of an instance is
15180 -- legal if the generic formal is untagged limited, and the actual
15183 if Is_Generic_Actual_Type (Parent_Type)
15184 and then In_Private_Part (Current_Scope)
15187 (Generic_Parent_Type (Parent (Parent_Type)))
15193 ("parent type& of limited type must be limited",
15199 -- In SPARK, there are no derived type definitions other than type
15200 -- extensions of tagged record types.
15202 if No (Extension) then
15203 Check_SPARK_Restriction
15204 ("derived type is not allowed", Original_Node (N));
15206 end Derived_Type_Declaration;
15208 ------------------------
15209 -- Diagnose_Interface --
15210 ------------------------
15212 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15214 if not Is_Interface (E)
15215 and then E /= Any_Type
15217 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15219 end Diagnose_Interface;
15221 ----------------------------------
15222 -- Enumeration_Type_Declaration --
15223 ----------------------------------
15225 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15232 -- Create identifier node representing lower bound
15234 B_Node := New_Node (N_Identifier, Sloc (Def));
15235 L := First (Literals (Def));
15236 Set_Chars (B_Node, Chars (L));
15237 Set_Entity (B_Node, L);
15238 Set_Etype (B_Node, T);
15239 Set_Is_Static_Expression (B_Node, True);
15241 R_Node := New_Node (N_Range, Sloc (Def));
15242 Set_Low_Bound (R_Node, B_Node);
15244 Set_Ekind (T, E_Enumeration_Type);
15245 Set_First_Literal (T, L);
15247 Set_Is_Constrained (T);
15251 -- Loop through literals of enumeration type setting pos and rep values
15252 -- except that if the Ekind is already set, then it means the literal
15253 -- was already constructed (case of a derived type declaration and we
15254 -- should not disturb the Pos and Rep values.
15256 while Present (L) loop
15257 if Ekind (L) /= E_Enumeration_Literal then
15258 Set_Ekind (L, E_Enumeration_Literal);
15259 Set_Enumeration_Pos (L, Ev);
15260 Set_Enumeration_Rep (L, Ev);
15261 Set_Is_Known_Valid (L, True);
15265 New_Overloaded_Entity (L);
15266 Generate_Definition (L);
15267 Set_Convention (L, Convention_Intrinsic);
15269 -- Case of character literal
15271 if Nkind (L) = N_Defining_Character_Literal then
15272 Set_Is_Character_Type (T, True);
15274 -- Check violation of No_Wide_Characters
15276 if Restriction_Check_Required (No_Wide_Characters) then
15277 Get_Name_String (Chars (L));
15279 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
15280 Check_Restriction (No_Wide_Characters, L);
15289 -- Now create a node representing upper bound
15291 B_Node := New_Node (N_Identifier, Sloc (Def));
15292 Set_Chars (B_Node, Chars (Last (Literals (Def))));
15293 Set_Entity (B_Node, Last (Literals (Def)));
15294 Set_Etype (B_Node, T);
15295 Set_Is_Static_Expression (B_Node, True);
15297 Set_High_Bound (R_Node, B_Node);
15299 -- Initialize various fields of the type. Some of this information
15300 -- may be overwritten later through rep.clauses.
15302 Set_Scalar_Range (T, R_Node);
15303 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
15304 Set_Enum_Esize (T);
15305 Set_Enum_Pos_To_Rep (T, Empty);
15307 -- Set Discard_Names if configuration pragma set, or if there is
15308 -- a parameterless pragma in the current declarative region
15310 if Global_Discard_Names or else Discard_Names (Scope (T)) then
15311 Set_Discard_Names (T);
15314 -- Process end label if there is one
15316 if Present (Def) then
15317 Process_End_Label (Def, 'e', T);
15319 end Enumeration_Type_Declaration;
15321 ---------------------------------
15322 -- Expand_To_Stored_Constraint --
15323 ---------------------------------
15325 function Expand_To_Stored_Constraint
15327 Constraint : Elist_Id) return Elist_Id
15329 Explicitly_Discriminated_Type : Entity_Id;
15330 Expansion : Elist_Id;
15331 Discriminant : Entity_Id;
15333 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
15334 -- Find the nearest type that actually specifies discriminants
15336 ---------------------------------
15337 -- Type_With_Explicit_Discrims --
15338 ---------------------------------
15340 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
15341 Typ : constant E := Base_Type (Id);
15344 if Ekind (Typ) in Incomplete_Or_Private_Kind then
15345 if Present (Full_View (Typ)) then
15346 return Type_With_Explicit_Discrims (Full_View (Typ));
15350 if Has_Discriminants (Typ) then
15355 if Etype (Typ) = Typ then
15357 elsif Has_Discriminants (Typ) then
15360 return Type_With_Explicit_Discrims (Etype (Typ));
15363 end Type_With_Explicit_Discrims;
15365 -- Start of processing for Expand_To_Stored_Constraint
15369 or else Is_Empty_Elmt_List (Constraint)
15374 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
15376 if No (Explicitly_Discriminated_Type) then
15380 Expansion := New_Elmt_List;
15383 First_Stored_Discriminant (Explicitly_Discriminated_Type);
15384 while Present (Discriminant) loop
15386 Get_Discriminant_Value (
15387 Discriminant, Explicitly_Discriminated_Type, Constraint),
15389 Next_Stored_Discriminant (Discriminant);
15393 end Expand_To_Stored_Constraint;
15395 ---------------------------
15396 -- Find_Hidden_Interface --
15397 ---------------------------
15399 function Find_Hidden_Interface
15401 Dest : Elist_Id) return Entity_Id
15404 Iface_Elmt : Elmt_Id;
15407 if Present (Src) and then Present (Dest) then
15408 Iface_Elmt := First_Elmt (Src);
15409 while Present (Iface_Elmt) loop
15410 Iface := Node (Iface_Elmt);
15412 if Is_Interface (Iface)
15413 and then not Contain_Interface (Iface, Dest)
15418 Next_Elmt (Iface_Elmt);
15423 end Find_Hidden_Interface;
15425 --------------------
15426 -- Find_Type_Name --
15427 --------------------
15429 function Find_Type_Name (N : Node_Id) return Entity_Id is
15430 Id : constant Entity_Id := Defining_Identifier (N);
15432 New_Id : Entity_Id;
15433 Prev_Par : Node_Id;
15435 procedure Check_Duplicate_Aspects;
15436 -- Check that aspects specified in a completion have not been specified
15437 -- already in the partial view. Type_Invariant and others can be
15438 -- specified on either view but never on both.
15440 procedure Tag_Mismatch;
15441 -- Diagnose a tagged partial view whose full view is untagged.
15442 -- We post the message on the full view, with a reference to
15443 -- the previous partial view. The partial view can be private
15444 -- or incomplete, and these are handled in a different manner,
15445 -- so we determine the position of the error message from the
15446 -- respective slocs of both.
15448 -----------------------------
15449 -- Check_Duplicate_Aspects --
15450 -----------------------------
15451 procedure Check_Duplicate_Aspects is
15452 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
15453 Full_Aspects : constant List_Id := Aspect_Specifications (N);
15454 F_Spec, P_Spec : Node_Id;
15457 if Present (Prev_Aspects) and then Present (Full_Aspects) then
15458 F_Spec := First (Full_Aspects);
15459 while Present (F_Spec) loop
15460 P_Spec := First (Prev_Aspects);
15461 while Present (P_Spec) loop
15463 Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
15466 ("aspect already specified in private declaration",
15478 end Check_Duplicate_Aspects;
15484 procedure Tag_Mismatch is
15486 if Sloc (Prev) < Sloc (Id) then
15487 if Ada_Version >= Ada_2012
15488 and then Nkind (N) = N_Private_Type_Declaration
15491 ("declaration of private } must be a tagged type ", Id, Prev);
15494 ("full declaration of } must be a tagged type ", Id, Prev);
15498 if Ada_Version >= Ada_2012
15499 and then Nkind (N) = N_Private_Type_Declaration
15502 ("declaration of private } must be a tagged type ", Prev, Id);
15505 ("full declaration of } must be a tagged type ", Prev, Id);
15510 -- Start of processing for Find_Type_Name
15513 -- Find incomplete declaration, if one was given
15515 Prev := Current_Entity_In_Scope (Id);
15517 -- New type declaration
15523 -- Previous declaration exists
15526 Prev_Par := Parent (Prev);
15528 -- Error if not incomplete/private case except if previous
15529 -- declaration is implicit, etc. Enter_Name will emit error if
15532 if not Is_Incomplete_Or_Private_Type (Prev) then
15536 -- Check invalid completion of private or incomplete type
15538 elsif not Nkind_In (N, N_Full_Type_Declaration,
15539 N_Task_Type_Declaration,
15540 N_Protected_Type_Declaration)
15542 (Ada_Version < Ada_2012
15543 or else not Is_Incomplete_Type (Prev)
15544 or else not Nkind_In (N, N_Private_Type_Declaration,
15545 N_Private_Extension_Declaration))
15547 -- Completion must be a full type declarations (RM 7.3(4))
15549 Error_Msg_Sloc := Sloc (Prev);
15550 Error_Msg_NE ("invalid completion of }", Id, Prev);
15552 -- Set scope of Id to avoid cascaded errors. Entity is never
15553 -- examined again, except when saving globals in generics.
15555 Set_Scope (Id, Current_Scope);
15558 -- If this is a repeated incomplete declaration, no further
15559 -- checks are possible.
15561 if Nkind (N) = N_Incomplete_Type_Declaration then
15565 -- Case of full declaration of incomplete type
15567 elsif Ekind (Prev) = E_Incomplete_Type
15568 and then (Ada_Version < Ada_2012
15569 or else No (Full_View (Prev))
15570 or else not Is_Private_Type (Full_View (Prev)))
15572 -- Indicate that the incomplete declaration has a matching full
15573 -- declaration. The defining occurrence of the incomplete
15574 -- declaration remains the visible one, and the procedure
15575 -- Get_Full_View dereferences it whenever the type is used.
15577 if Present (Full_View (Prev)) then
15578 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15581 Set_Full_View (Prev, Id);
15582 Append_Entity (Id, Current_Scope);
15583 Set_Is_Public (Id, Is_Public (Prev));
15584 Set_Is_Internal (Id);
15587 -- If the incomplete view is tagged, a class_wide type has been
15588 -- created already. Use it for the private type as well, in order
15589 -- to prevent multiple incompatible class-wide types that may be
15590 -- created for self-referential anonymous access components.
15592 if Is_Tagged_Type (Prev)
15593 and then Present (Class_Wide_Type (Prev))
15595 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
15596 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
15598 -- If the incomplete type is completed by a private declaration
15599 -- the class-wide type remains associated with the incomplete
15600 -- type, to prevent order-of-elaboration issues in gigi, else
15601 -- we associate the class-wide type with the known full view.
15603 if Nkind (N) /= N_Private_Type_Declaration then
15604 Set_Etype (Class_Wide_Type (Id), Id);
15608 -- Case of full declaration of private type
15611 -- If the private type was a completion of an incomplete type then
15612 -- update Prev to reference the private type
15614 if Ada_Version >= Ada_2012
15615 and then Ekind (Prev) = E_Incomplete_Type
15616 and then Present (Full_View (Prev))
15617 and then Is_Private_Type (Full_View (Prev))
15619 Prev := Full_View (Prev);
15620 Prev_Par := Parent (Prev);
15623 if Nkind (N) = N_Full_Type_Declaration
15625 (Type_Definition (N), N_Record_Definition,
15626 N_Derived_Type_Definition)
15627 and then Interface_Present (Type_Definition (N))
15630 ("completion of private type cannot be an interface", N);
15633 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
15634 if Etype (Prev) /= Prev then
15636 -- Prev is a private subtype or a derived type, and needs
15639 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15642 elsif Ekind (Prev) = E_Private_Type
15643 and then Nkind_In (N, N_Task_Type_Declaration,
15644 N_Protected_Type_Declaration)
15647 ("completion of nonlimited type cannot be limited", N);
15649 elsif Ekind (Prev) = E_Record_Type_With_Private
15650 and then Nkind_In (N, N_Task_Type_Declaration,
15651 N_Protected_Type_Declaration)
15653 if not Is_Limited_Record (Prev) then
15655 ("completion of nonlimited type cannot be limited", N);
15657 elsif No (Interface_List (N)) then
15659 ("completion of tagged private type must be tagged",
15664 -- Ada 2005 (AI-251): Private extension declaration of a task
15665 -- type or a protected type. This case arises when covering
15666 -- interface types.
15668 elsif Nkind_In (N, N_Task_Type_Declaration,
15669 N_Protected_Type_Declaration)
15673 elsif Nkind (N) /= N_Full_Type_Declaration
15674 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
15677 ("full view of private extension must be an extension", N);
15679 elsif not (Abstract_Present (Parent (Prev)))
15680 and then Abstract_Present (Type_Definition (N))
15683 ("full view of non-abstract extension cannot be abstract", N);
15686 if not In_Private_Part (Current_Scope) then
15688 ("declaration of full view must appear in private part", N);
15691 if Ada_Version >= Ada_2012 then
15692 Check_Duplicate_Aspects;
15695 Copy_And_Swap (Prev, Id);
15696 Set_Has_Private_Declaration (Prev);
15697 Set_Has_Private_Declaration (Id);
15699 -- Preserve aspect and iterator flags that may have been set on
15700 -- the partial view.
15702 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
15703 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
15705 -- If no error, propagate freeze_node from private to full view.
15706 -- It may have been generated for an early operational item.
15708 if Present (Freeze_Node (Id))
15709 and then Serious_Errors_Detected = 0
15710 and then No (Full_View (Id))
15712 Set_Freeze_Node (Prev, Freeze_Node (Id));
15713 Set_Freeze_Node (Id, Empty);
15714 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
15717 Set_Full_View (Id, Prev);
15721 -- Verify that full declaration conforms to partial one
15723 if Is_Incomplete_Or_Private_Type (Prev)
15724 and then Present (Discriminant_Specifications (Prev_Par))
15726 if Present (Discriminant_Specifications (N)) then
15727 if Ekind (Prev) = E_Incomplete_Type then
15728 Check_Discriminant_Conformance (N, Prev, Prev);
15730 Check_Discriminant_Conformance (N, Prev, Id);
15735 ("missing discriminants in full type declaration", N);
15737 -- To avoid cascaded errors on subsequent use, share the
15738 -- discriminants of the partial view.
15740 Set_Discriminant_Specifications (N,
15741 Discriminant_Specifications (Prev_Par));
15745 -- A prior untagged partial view can have an associated class-wide
15746 -- type due to use of the class attribute, and in this case the full
15747 -- type must also be tagged. This Ada 95 usage is deprecated in favor
15748 -- of incomplete tagged declarations, but we check for it.
15751 and then (Is_Tagged_Type (Prev)
15752 or else Present (Class_Wide_Type (Prev)))
15754 -- Ada 2012 (AI05-0162): A private type may be the completion of
15755 -- an incomplete type.
15757 if Ada_Version >= Ada_2012
15758 and then Is_Incomplete_Type (Prev)
15759 and then Nkind_In (N, N_Private_Type_Declaration,
15760 N_Private_Extension_Declaration)
15762 -- No need to check private extensions since they are tagged
15764 if Nkind (N) = N_Private_Type_Declaration
15765 and then not Tagged_Present (N)
15770 -- The full declaration is either a tagged type (including
15771 -- a synchronized type that implements interfaces) or a
15772 -- type extension, otherwise this is an error.
15774 elsif Nkind_In (N, N_Task_Type_Declaration,
15775 N_Protected_Type_Declaration)
15777 if No (Interface_List (N))
15778 and then not Error_Posted (N)
15783 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15785 -- Indicate that the previous declaration (tagged incomplete
15786 -- or private declaration) requires the same on the full one.
15788 if not Tagged_Present (Type_Definition (N)) then
15790 Set_Is_Tagged_Type (Id);
15793 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15794 if No (Record_Extension_Part (Type_Definition (N))) then
15796 ("full declaration of } must be a record extension",
15799 -- Set some attributes to produce a usable full view
15801 Set_Is_Tagged_Type (Id);
15810 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
15811 and then Present (Premature_Use (Parent (Prev)))
15813 Error_Msg_Sloc := Sloc (N);
15815 ("\full declaration #", Premature_Use (Parent (Prev)));
15820 end Find_Type_Name;
15822 -------------------------
15823 -- Find_Type_Of_Object --
15824 -------------------------
15826 function Find_Type_Of_Object
15827 (Obj_Def : Node_Id;
15828 Related_Nod : Node_Id) return Entity_Id
15830 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15831 P : Node_Id := Parent (Obj_Def);
15836 -- If the parent is a component_definition node we climb to the
15837 -- component_declaration node
15839 if Nkind (P) = N_Component_Definition then
15843 -- Case of an anonymous array subtype
15845 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15846 N_Unconstrained_Array_Definition)
15849 Array_Type_Declaration (T, Obj_Def);
15851 -- Create an explicit subtype whenever possible
15853 elsif Nkind (P) /= N_Component_Declaration
15854 and then Def_Kind = N_Subtype_Indication
15856 -- Base name of subtype on object name, which will be unique in
15857 -- the current scope.
15859 -- If this is a duplicate declaration, return base type, to avoid
15860 -- generating duplicate anonymous types.
15862 if Error_Posted (P) then
15863 Analyze (Subtype_Mark (Obj_Def));
15864 return Entity (Subtype_Mark (Obj_Def));
15869 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15871 T := Make_Defining_Identifier (Sloc (P), Nam);
15873 Insert_Action (Obj_Def,
15874 Make_Subtype_Declaration (Sloc (P),
15875 Defining_Identifier => T,
15876 Subtype_Indication => Relocate_Node (Obj_Def)));
15878 -- This subtype may need freezing, and this will not be done
15879 -- automatically if the object declaration is not in declarative
15880 -- part. Since this is an object declaration, the type cannot always
15881 -- be frozen here. Deferred constants do not freeze their type
15882 -- (which often enough will be private).
15884 if Nkind (P) = N_Object_Declaration
15885 and then Constant_Present (P)
15886 and then No (Expression (P))
15890 -- Here we freeze the base type of object type to catch premature use
15891 -- of discriminated private type without a full view.
15894 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
15897 -- Ada 2005 AI-406: the object definition in an object declaration
15898 -- can be an access definition.
15900 elsif Def_Kind = N_Access_Definition then
15901 T := Access_Definition (Related_Nod, Obj_Def);
15903 Set_Is_Local_Anonymous_Access
15905 V => (Ada_Version < Ada_2012)
15906 or else (Nkind (P) /= N_Object_Declaration)
15907 or else Is_Library_Level_Entity (Defining_Identifier (P)));
15909 -- Otherwise, the object definition is just a subtype_mark
15912 T := Process_Subtype (Obj_Def, Related_Nod);
15914 -- If expansion is disabled an object definition that is an aggregate
15915 -- will not get expanded and may lead to scoping problems in the back
15916 -- end, if the object is referenced in an inner scope. In that case
15917 -- create an itype reference for the object definition now. This
15918 -- may be redundant in some cases, but harmless.
15921 and then Nkind (Related_Nod) = N_Object_Declaration
15924 Build_Itype_Reference (T, Related_Nod);
15929 end Find_Type_Of_Object;
15931 --------------------------------
15932 -- Find_Type_Of_Subtype_Indic --
15933 --------------------------------
15935 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15939 -- Case of subtype mark with a constraint
15941 if Nkind (S) = N_Subtype_Indication then
15942 Find_Type (Subtype_Mark (S));
15943 Typ := Entity (Subtype_Mark (S));
15946 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15949 ("incorrect constraint for this kind of type", Constraint (S));
15950 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15953 -- Otherwise we have a subtype mark without a constraint
15955 elsif Error_Posted (S) then
15956 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15964 -- Check No_Wide_Characters restriction
15966 Check_Wide_Character_Restriction (Typ, S);
15969 end Find_Type_Of_Subtype_Indic;
15971 -------------------------------------
15972 -- Floating_Point_Type_Declaration --
15973 -------------------------------------
15975 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15976 Digs : constant Node_Id := Digits_Expression (Def);
15977 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15979 Base_Typ : Entity_Id;
15980 Implicit_Base : Entity_Id;
15983 function Can_Derive_From (E : Entity_Id) return Boolean;
15984 -- Find if given digits value, and possibly a specified range, allows
15985 -- derivation from specified type
15987 function Find_Base_Type return Entity_Id;
15988 -- Find a predefined base type that Def can derive from, or generate
15989 -- an error and substitute Long_Long_Float if none exists.
15991 ---------------------
15992 -- Can_Derive_From --
15993 ---------------------
15995 function Can_Derive_From (E : Entity_Id) return Boolean is
15996 Spec : constant Entity_Id := Real_Range_Specification (Def);
15999 -- Check specified "digits" constraint
16001 if Digs_Val > Digits_Value (E) then
16005 -- Avoid types not matching pragma Float_Representation, if present
16007 if (Opt.Float_Format = 'I' and then Float_Rep (E) /= IEEE_Binary)
16009 (Opt.Float_Format = 'V' and then Float_Rep (E) /= VAX_Native)
16014 -- Check for matching range, if specified
16016 if Present (Spec) then
16017 if Expr_Value_R (Type_Low_Bound (E)) >
16018 Expr_Value_R (Low_Bound (Spec))
16023 if Expr_Value_R (Type_High_Bound (E)) <
16024 Expr_Value_R (High_Bound (Spec))
16031 end Can_Derive_From;
16033 --------------------
16034 -- Find_Base_Type --
16035 --------------------
16037 function Find_Base_Type return Entity_Id is
16038 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16041 -- Iterate over the predefined types in order, returning the first
16042 -- one that Def can derive from.
16044 while Present (Choice) loop
16045 if Can_Derive_From (Node (Choice)) then
16046 return Node (Choice);
16049 Next_Elmt (Choice);
16052 -- If we can't derive from any existing type, use Long_Long_Float
16053 -- and give appropriate message explaining the problem.
16055 if Digs_Val > Max_Digs_Val then
16056 -- It might be the case that there is a type with the requested
16057 -- range, just not the combination of digits and range.
16060 ("no predefined type has requested range and precision",
16061 Real_Range_Specification (Def));
16065 ("range too large for any predefined type",
16066 Real_Range_Specification (Def));
16069 return Standard_Long_Long_Float;
16070 end Find_Base_Type;
16072 -- Start of processing for Floating_Point_Type_Declaration
16075 Check_Restriction (No_Floating_Point, Def);
16077 -- Create an implicit base type
16080 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16082 -- Analyze and verify digits value
16084 Analyze_And_Resolve (Digs, Any_Integer);
16085 Check_Digits_Expression (Digs);
16086 Digs_Val := Expr_Value (Digs);
16088 -- Process possible range spec and find correct type to derive from
16090 Process_Real_Range_Specification (Def);
16092 -- Check that requested number of digits is not too high.
16094 if Digs_Val > Max_Digs_Val then
16095 -- The check for Max_Base_Digits may be somewhat expensive, as it
16096 -- requires reading System, so only do it when necessary.
16099 Max_Base_Digits : constant Uint :=
16102 (Parent (RTE (RE_Max_Base_Digits))));
16105 if Digs_Val > Max_Base_Digits then
16106 Error_Msg_Uint_1 := Max_Base_Digits;
16107 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16109 elsif No (Real_Range_Specification (Def)) then
16110 Error_Msg_Uint_1 := Max_Digs_Val;
16111 Error_Msg_N ("types with more than ^ digits need range spec "
16112 & "(RM 3.5.7(6))", Digs);
16117 -- Find a suitable type to derive from or complain and use a substitute
16119 Base_Typ := Find_Base_Type;
16121 -- If there are bounds given in the declaration use them as the bounds
16122 -- of the type, otherwise use the bounds of the predefined base type
16123 -- that was chosen based on the Digits value.
16125 if Present (Real_Range_Specification (Def)) then
16126 Set_Scalar_Range (T, Real_Range_Specification (Def));
16127 Set_Is_Constrained (T);
16129 -- The bounds of this range must be converted to machine numbers
16130 -- in accordance with RM 4.9(38).
16132 Bound := Type_Low_Bound (T);
16134 if Nkind (Bound) = N_Real_Literal then
16136 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16137 Set_Is_Machine_Number (Bound);
16140 Bound := Type_High_Bound (T);
16142 if Nkind (Bound) = N_Real_Literal then
16144 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16145 Set_Is_Machine_Number (Bound);
16149 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16152 -- Complete definition of implicit base and declared first subtype
16154 Set_Etype (Implicit_Base, Base_Typ);
16156 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16157 Set_Size_Info (Implicit_Base, (Base_Typ));
16158 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16159 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16160 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16161 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16163 Set_Ekind (T, E_Floating_Point_Subtype);
16164 Set_Etype (T, Implicit_Base);
16166 Set_Size_Info (T, (Implicit_Base));
16167 Set_RM_Size (T, RM_Size (Implicit_Base));
16168 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16169 Set_Digits_Value (T, Digs_Val);
16170 end Floating_Point_Type_Declaration;
16172 ----------------------------
16173 -- Get_Discriminant_Value --
16174 ----------------------------
16176 -- This is the situation:
16178 -- There is a non-derived type
16180 -- type T0 (Dx, Dy, Dz...)
16182 -- There are zero or more levels of derivation, with each derivation
16183 -- either purely inheriting the discriminants, or defining its own.
16185 -- type Ti is new Ti-1
16187 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16189 -- subtype Ti is ...
16191 -- The subtype issue is avoided by the use of Original_Record_Component,
16192 -- and the fact that derived subtypes also derive the constraints.
16194 -- This chain leads back from
16196 -- Typ_For_Constraint
16198 -- Typ_For_Constraint has discriminants, and the value for each
16199 -- discriminant is given by its corresponding Elmt of Constraints.
16201 -- Discriminant is some discriminant in this hierarchy
16203 -- We need to return its value
16205 -- We do this by recursively searching each level, and looking for
16206 -- Discriminant. Once we get to the bottom, we start backing up
16207 -- returning the value for it which may in turn be a discriminant
16208 -- further up, so on the backup we continue the substitution.
16210 function Get_Discriminant_Value
16211 (Discriminant : Entity_Id;
16212 Typ_For_Constraint : Entity_Id;
16213 Constraint : Elist_Id) return Node_Id
16215 function Root_Corresponding_Discriminant
16216 (Discr : Entity_Id) return Entity_Id;
16217 -- Given a discriminant, traverse the chain of inherited discriminants
16218 -- and return the topmost discriminant.
16220 function Search_Derivation_Levels
16222 Discrim_Values : Elist_Id;
16223 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16224 -- This is the routine that performs the recursive search of levels
16225 -- as described above.
16227 -------------------------------------
16228 -- Root_Corresponding_Discriminant --
16229 -------------------------------------
16231 function Root_Corresponding_Discriminant
16232 (Discr : Entity_Id) return Entity_Id
16238 while Present (Corresponding_Discriminant (D)) loop
16239 D := Corresponding_Discriminant (D);
16243 end Root_Corresponding_Discriminant;
16245 ------------------------------
16246 -- Search_Derivation_Levels --
16247 ------------------------------
16249 function Search_Derivation_Levels
16251 Discrim_Values : Elist_Id;
16252 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
16256 Result : Node_Or_Entity_Id;
16257 Result_Entity : Node_Id;
16260 -- If inappropriate type, return Error, this happens only in
16261 -- cascaded error situations, and we want to avoid a blow up.
16263 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
16267 -- Look deeper if possible. Use Stored_Constraints only for
16268 -- untagged types. For tagged types use the given constraint.
16269 -- This asymmetry needs explanation???
16271 if not Stored_Discrim_Values
16272 and then Present (Stored_Constraint (Ti))
16273 and then not Is_Tagged_Type (Ti)
16276 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
16279 Td : constant Entity_Id := Etype (Ti);
16283 Result := Discriminant;
16286 if Present (Stored_Constraint (Ti)) then
16288 Search_Derivation_Levels
16289 (Td, Stored_Constraint (Ti), True);
16292 Search_Derivation_Levels
16293 (Td, Discrim_Values, Stored_Discrim_Values);
16299 -- Extra underlying places to search, if not found above. For
16300 -- concurrent types, the relevant discriminant appears in the
16301 -- corresponding record. For a type derived from a private type
16302 -- without discriminant, the full view inherits the discriminants
16303 -- of the full view of the parent.
16305 if Result = Discriminant then
16306 if Is_Concurrent_Type (Ti)
16307 and then Present (Corresponding_Record_Type (Ti))
16310 Search_Derivation_Levels (
16311 Corresponding_Record_Type (Ti),
16313 Stored_Discrim_Values);
16315 elsif Is_Private_Type (Ti)
16316 and then not Has_Discriminants (Ti)
16317 and then Present (Full_View (Ti))
16318 and then Etype (Full_View (Ti)) /= Ti
16321 Search_Derivation_Levels (
16324 Stored_Discrim_Values);
16328 -- If Result is not a (reference to a) discriminant, return it,
16329 -- otherwise set Result_Entity to the discriminant.
16331 if Nkind (Result) = N_Defining_Identifier then
16332 pragma Assert (Result = Discriminant);
16333 Result_Entity := Result;
16336 if not Denotes_Discriminant (Result) then
16340 Result_Entity := Entity (Result);
16343 -- See if this level of derivation actually has discriminants
16344 -- because tagged derivations can add them, hence the lower
16345 -- levels need not have any.
16347 if not Has_Discriminants (Ti) then
16351 -- Scan Ti's discriminants for Result_Entity,
16352 -- and return its corresponding value, if any.
16354 Result_Entity := Original_Record_Component (Result_Entity);
16356 Assoc := First_Elmt (Discrim_Values);
16358 if Stored_Discrim_Values then
16359 Disc := First_Stored_Discriminant (Ti);
16361 Disc := First_Discriminant (Ti);
16364 while Present (Disc) loop
16365 pragma Assert (Present (Assoc));
16367 if Original_Record_Component (Disc) = Result_Entity then
16368 return Node (Assoc);
16373 if Stored_Discrim_Values then
16374 Next_Stored_Discriminant (Disc);
16376 Next_Discriminant (Disc);
16380 -- Could not find it
16383 end Search_Derivation_Levels;
16387 Result : Node_Or_Entity_Id;
16389 -- Start of processing for Get_Discriminant_Value
16392 -- ??? This routine is a gigantic mess and will be deleted. For the
16393 -- time being just test for the trivial case before calling recurse.
16395 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
16401 D := First_Discriminant (Typ_For_Constraint);
16402 E := First_Elmt (Constraint);
16403 while Present (D) loop
16404 if Chars (D) = Chars (Discriminant) then
16408 Next_Discriminant (D);
16414 Result := Search_Derivation_Levels
16415 (Typ_For_Constraint, Constraint, False);
16417 -- ??? hack to disappear when this routine is gone
16419 if Nkind (Result) = N_Defining_Identifier then
16425 D := First_Discriminant (Typ_For_Constraint);
16426 E := First_Elmt (Constraint);
16427 while Present (D) loop
16428 if Root_Corresponding_Discriminant (D) = Discriminant then
16432 Next_Discriminant (D);
16438 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
16440 end Get_Discriminant_Value;
16442 --------------------------
16443 -- Has_Range_Constraint --
16444 --------------------------
16446 function Has_Range_Constraint (N : Node_Id) return Boolean is
16447 C : constant Node_Id := Constraint (N);
16450 if Nkind (C) = N_Range_Constraint then
16453 elsif Nkind (C) = N_Digits_Constraint then
16455 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
16457 Present (Range_Constraint (C));
16459 elsif Nkind (C) = N_Delta_Constraint then
16460 return Present (Range_Constraint (C));
16465 end Has_Range_Constraint;
16467 ------------------------
16468 -- Inherit_Components --
16469 ------------------------
16471 function Inherit_Components
16473 Parent_Base : Entity_Id;
16474 Derived_Base : Entity_Id;
16475 Is_Tagged : Boolean;
16476 Inherit_Discr : Boolean;
16477 Discs : Elist_Id) return Elist_Id
16479 Assoc_List : constant Elist_Id := New_Elmt_List;
16481 procedure Inherit_Component
16482 (Old_C : Entity_Id;
16483 Plain_Discrim : Boolean := False;
16484 Stored_Discrim : Boolean := False);
16485 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
16486 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
16487 -- True, Old_C is a stored discriminant. If they are both false then
16488 -- Old_C is a regular component.
16490 -----------------------
16491 -- Inherit_Component --
16492 -----------------------
16494 procedure Inherit_Component
16495 (Old_C : Entity_Id;
16496 Plain_Discrim : Boolean := False;
16497 Stored_Discrim : Boolean := False)
16499 procedure Set_Anonymous_Type (Id : Entity_Id);
16500 -- Id denotes the entity of an access discriminant or anonymous
16501 -- access component. Set the type of Id to either the same type of
16502 -- Old_C or create a new one depending on whether the parent and
16503 -- the child types are in the same scope.
16505 ------------------------
16506 -- Set_Anonymous_Type --
16507 ------------------------
16509 procedure Set_Anonymous_Type (Id : Entity_Id) is
16510 Old_Typ : constant Entity_Id := Etype (Old_C);
16513 if Scope (Parent_Base) = Scope (Derived_Base) then
16514 Set_Etype (Id, Old_Typ);
16516 -- The parent and the derived type are in two different scopes.
16517 -- Reuse the type of the original discriminant / component by
16518 -- copying it in order to preserve all attributes.
16522 Typ : constant Entity_Id := New_Copy (Old_Typ);
16525 Set_Etype (Id, Typ);
16527 -- Since we do not generate component declarations for
16528 -- inherited components, associate the itype with the
16531 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
16532 Set_Scope (Typ, Derived_Base);
16535 end Set_Anonymous_Type;
16537 -- Local variables and constants
16539 New_C : constant Entity_Id := New_Copy (Old_C);
16541 Corr_Discrim : Entity_Id;
16542 Discrim : Entity_Id;
16544 -- Start of processing for Inherit_Component
16547 pragma Assert (not Is_Tagged or else not Stored_Discrim);
16549 Set_Parent (New_C, Parent (Old_C));
16551 -- Regular discriminants and components must be inserted in the scope
16552 -- of the Derived_Base. Do it here.
16554 if not Stored_Discrim then
16555 Enter_Name (New_C);
16558 -- For tagged types the Original_Record_Component must point to
16559 -- whatever this field was pointing to in the parent type. This has
16560 -- already been achieved by the call to New_Copy above.
16562 if not Is_Tagged then
16563 Set_Original_Record_Component (New_C, New_C);
16566 -- Set the proper type of an access discriminant
16568 if Ekind (New_C) = E_Discriminant
16569 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
16571 Set_Anonymous_Type (New_C);
16574 -- If we have inherited a component then see if its Etype contains
16575 -- references to Parent_Base discriminants. In this case, replace
16576 -- these references with the constraints given in Discs. We do not
16577 -- do this for the partial view of private types because this is
16578 -- not needed (only the components of the full view will be used
16579 -- for code generation) and cause problem. We also avoid this
16580 -- transformation in some error situations.
16582 if Ekind (New_C) = E_Component then
16584 -- Set the proper type of an anonymous access component
16586 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
16587 Set_Anonymous_Type (New_C);
16589 elsif (Is_Private_Type (Derived_Base)
16590 and then not Is_Generic_Type (Derived_Base))
16591 or else (Is_Empty_Elmt_List (Discs)
16592 and then not Expander_Active)
16594 Set_Etype (New_C, Etype (Old_C));
16597 -- The current component introduces a circularity of the
16600 -- limited with Pack_2;
16601 -- package Pack_1 is
16602 -- type T_1 is tagged record
16603 -- Comp : access Pack_2.T_2;
16609 -- package Pack_2 is
16610 -- type T_2 is new Pack_1.T_1 with ...;
16615 Constrain_Component_Type
16616 (Old_C, Derived_Base, N, Parent_Base, Discs));
16620 -- In derived tagged types it is illegal to reference a non
16621 -- discriminant component in the parent type. To catch this, mark
16622 -- these components with an Ekind of E_Void. This will be reset in
16623 -- Record_Type_Definition after processing the record extension of
16624 -- the derived type.
16626 -- If the declaration is a private extension, there is no further
16627 -- record extension to process, and the components retain their
16628 -- current kind, because they are visible at this point.
16630 if Is_Tagged and then Ekind (New_C) = E_Component
16631 and then Nkind (N) /= N_Private_Extension_Declaration
16633 Set_Ekind (New_C, E_Void);
16636 if Plain_Discrim then
16637 Set_Corresponding_Discriminant (New_C, Old_C);
16638 Build_Discriminal (New_C);
16640 -- If we are explicitly inheriting a stored discriminant it will be
16641 -- completely hidden.
16643 elsif Stored_Discrim then
16644 Set_Corresponding_Discriminant (New_C, Empty);
16645 Set_Discriminal (New_C, Empty);
16646 Set_Is_Completely_Hidden (New_C);
16648 -- Set the Original_Record_Component of each discriminant in the
16649 -- derived base to point to the corresponding stored that we just
16652 Discrim := First_Discriminant (Derived_Base);
16653 while Present (Discrim) loop
16654 Corr_Discrim := Corresponding_Discriminant (Discrim);
16656 -- Corr_Discrim could be missing in an error situation
16658 if Present (Corr_Discrim)
16659 and then Original_Record_Component (Corr_Discrim) = Old_C
16661 Set_Original_Record_Component (Discrim, New_C);
16664 Next_Discriminant (Discrim);
16667 Append_Entity (New_C, Derived_Base);
16670 if not Is_Tagged then
16671 Append_Elmt (Old_C, Assoc_List);
16672 Append_Elmt (New_C, Assoc_List);
16674 end Inherit_Component;
16676 -- Variables local to Inherit_Component
16678 Loc : constant Source_Ptr := Sloc (N);
16680 Parent_Discrim : Entity_Id;
16681 Stored_Discrim : Entity_Id;
16683 Component : Entity_Id;
16685 -- Start of processing for Inherit_Components
16688 if not Is_Tagged then
16689 Append_Elmt (Parent_Base, Assoc_List);
16690 Append_Elmt (Derived_Base, Assoc_List);
16693 -- Inherit parent discriminants if needed
16695 if Inherit_Discr then
16696 Parent_Discrim := First_Discriminant (Parent_Base);
16697 while Present (Parent_Discrim) loop
16698 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
16699 Next_Discriminant (Parent_Discrim);
16703 -- Create explicit stored discrims for untagged types when necessary
16705 if not Has_Unknown_Discriminants (Derived_Base)
16706 and then Has_Discriminants (Parent_Base)
16707 and then not Is_Tagged
16710 or else First_Discriminant (Parent_Base) /=
16711 First_Stored_Discriminant (Parent_Base))
16713 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
16714 while Present (Stored_Discrim) loop
16715 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
16716 Next_Stored_Discriminant (Stored_Discrim);
16720 -- See if we can apply the second transformation for derived types, as
16721 -- explained in point 6. in the comments above Build_Derived_Record_Type
16722 -- This is achieved by appending Derived_Base discriminants into Discs,
16723 -- which has the side effect of returning a non empty Discs list to the
16724 -- caller of Inherit_Components, which is what we want. This must be
16725 -- done for private derived types if there are explicit stored
16726 -- discriminants, to ensure that we can retrieve the values of the
16727 -- constraints provided in the ancestors.
16730 and then Is_Empty_Elmt_List (Discs)
16731 and then Present (First_Discriminant (Derived_Base))
16733 (not Is_Private_Type (Derived_Base)
16734 or else Is_Completely_Hidden
16735 (First_Stored_Discriminant (Derived_Base))
16736 or else Is_Generic_Type (Derived_Base))
16738 D := First_Discriminant (Derived_Base);
16739 while Present (D) loop
16740 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
16741 Next_Discriminant (D);
16745 -- Finally, inherit non-discriminant components unless they are not
16746 -- visible because defined or inherited from the full view of the
16747 -- parent. Don't inherit the _parent field of the parent type.
16749 Component := First_Entity (Parent_Base);
16750 while Present (Component) loop
16752 -- Ada 2005 (AI-251): Do not inherit components associated with
16753 -- secondary tags of the parent.
16755 if Ekind (Component) = E_Component
16756 and then Present (Related_Type (Component))
16760 elsif Ekind (Component) /= E_Component
16761 or else Chars (Component) = Name_uParent
16765 -- If the derived type is within the parent type's declarative
16766 -- region, then the components can still be inherited even though
16767 -- they aren't visible at this point. This can occur for cases
16768 -- such as within public child units where the components must
16769 -- become visible upon entering the child unit's private part.
16771 elsif not Is_Visible_Component (Component)
16772 and then not In_Open_Scopes (Scope (Parent_Base))
16776 elsif Ekind_In (Derived_Base, E_Private_Type,
16777 E_Limited_Private_Type)
16782 Inherit_Component (Component);
16785 Next_Entity (Component);
16788 -- For tagged derived types, inherited discriminants cannot be used in
16789 -- component declarations of the record extension part. To achieve this
16790 -- we mark the inherited discriminants as not visible.
16792 if Is_Tagged and then Inherit_Discr then
16793 D := First_Discriminant (Derived_Base);
16794 while Present (D) loop
16795 Set_Is_Immediately_Visible (D, False);
16796 Next_Discriminant (D);
16801 end Inherit_Components;
16803 -----------------------
16804 -- Is_Null_Extension --
16805 -----------------------
16807 function Is_Null_Extension (T : Entity_Id) return Boolean is
16808 Type_Decl : constant Node_Id := Parent (Base_Type (T));
16809 Comp_List : Node_Id;
16813 if Nkind (Type_Decl) /= N_Full_Type_Declaration
16814 or else not Is_Tagged_Type (T)
16815 or else Nkind (Type_Definition (Type_Decl)) /=
16816 N_Derived_Type_Definition
16817 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
16823 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
16825 if Present (Discriminant_Specifications (Type_Decl)) then
16828 elsif Present (Comp_List)
16829 and then Is_Non_Empty_List (Component_Items (Comp_List))
16831 Comp := First (Component_Items (Comp_List));
16833 -- Only user-defined components are relevant. The component list
16834 -- may also contain a parent component and internal components
16835 -- corresponding to secondary tags, but these do not determine
16836 -- whether this is a null extension.
16838 while Present (Comp) loop
16839 if Comes_From_Source (Comp) then
16850 end Is_Null_Extension;
16852 ------------------------------
16853 -- Is_Valid_Constraint_Kind --
16854 ------------------------------
16856 function Is_Valid_Constraint_Kind
16857 (T_Kind : Type_Kind;
16858 Constraint_Kind : Node_Kind) return Boolean
16862 when Enumeration_Kind |
16864 return Constraint_Kind = N_Range_Constraint;
16866 when Decimal_Fixed_Point_Kind =>
16867 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16868 N_Range_Constraint);
16870 when Ordinary_Fixed_Point_Kind =>
16871 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16872 N_Range_Constraint);
16875 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16876 N_Range_Constraint);
16883 E_Incomplete_Type |
16886 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16889 return True; -- Error will be detected later
16891 end Is_Valid_Constraint_Kind;
16893 --------------------------
16894 -- Is_Visible_Component --
16895 --------------------------
16897 function Is_Visible_Component
16899 N : Node_Id := Empty) return Boolean
16901 Original_Comp : Entity_Id := Empty;
16902 Original_Scope : Entity_Id;
16903 Type_Scope : Entity_Id;
16905 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16906 -- Check whether parent type of inherited component is declared locally,
16907 -- possibly within a nested package or instance. The current scope is
16908 -- the derived record itself.
16910 -------------------
16911 -- Is_Local_Type --
16912 -------------------
16914 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16918 Scop := Scope (Typ);
16919 while Present (Scop)
16920 and then Scop /= Standard_Standard
16922 if Scop = Scope (Current_Scope) then
16926 Scop := Scope (Scop);
16932 -- Start of processing for Is_Visible_Component
16935 if Ekind_In (C, E_Component, E_Discriminant) then
16936 Original_Comp := Original_Record_Component (C);
16939 if No (Original_Comp) then
16941 -- Premature usage, or previous error
16946 Original_Scope := Scope (Original_Comp);
16947 Type_Scope := Scope (Base_Type (Scope (C)));
16950 -- For an untagged type derived from a private type, the only visible
16951 -- components are new discriminants. In an instance all components are
16952 -- visible (see Analyze_Selected_Component).
16954 if not Is_Tagged_Type (Original_Scope) then
16955 return not Has_Private_Ancestor (Original_Scope)
16956 or else In_Open_Scopes (Scope (Original_Scope))
16957 or else In_Instance
16958 or else (Ekind (Original_Comp) = E_Discriminant
16959 and then Original_Scope = Type_Scope);
16961 -- If it is _Parent or _Tag, there is no visibility issue
16963 elsif not Comes_From_Source (Original_Comp) then
16966 -- Discriminants are visible unless the (private) type has unknown
16967 -- discriminants. If the discriminant reference is inserted for a
16968 -- discriminant check on a full view it is also visible.
16970 elsif Ekind (Original_Comp) = E_Discriminant
16972 (not Has_Unknown_Discriminants (Original_Scope)
16973 or else (Present (N)
16974 and then Nkind (N) = N_Selected_Component
16975 and then Nkind (Prefix (N)) = N_Type_Conversion
16976 and then not Comes_From_Source (Prefix (N))))
16980 -- In the body of an instantiation, no need to check for the visibility
16983 elsif In_Instance_Body then
16986 -- If the component has been declared in an ancestor which is currently
16987 -- a private type, then it is not visible. The same applies if the
16988 -- component's containing type is not in an open scope and the original
16989 -- component's enclosing type is a visible full view of a private type
16990 -- (which can occur in cases where an attempt is being made to reference
16991 -- a component in a sibling package that is inherited from a visible
16992 -- component of a type in an ancestor package; the component in the
16993 -- sibling package should not be visible even though the component it
16994 -- inherited from is visible). This does not apply however in the case
16995 -- where the scope of the type is a private child unit, or when the
16996 -- parent comes from a local package in which the ancestor is currently
16997 -- visible. The latter suppression of visibility is needed for cases
16998 -- that are tested in B730006.
17000 elsif Is_Private_Type (Original_Scope)
17002 (not Is_Private_Descendant (Type_Scope)
17003 and then not In_Open_Scopes (Type_Scope)
17004 and then Has_Private_Declaration (Original_Scope))
17006 -- If the type derives from an entity in a formal package, there
17007 -- are no additional visible components.
17009 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17010 N_Formal_Package_Declaration
17014 -- if we are not in the private part of the current package, there
17015 -- are no additional visible components.
17017 elsif Ekind (Scope (Current_Scope)) = E_Package
17018 and then not In_Private_Part (Scope (Current_Scope))
17023 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17024 and then In_Open_Scopes (Scope (Original_Scope))
17025 and then Is_Local_Type (Type_Scope);
17028 -- There is another weird way in which a component may be invisible when
17029 -- the private and the full view are not derived from the same ancestor.
17030 -- Here is an example :
17032 -- type A1 is tagged record F1 : integer; end record;
17033 -- type A2 is new A1 with record F2 : integer; end record;
17034 -- type T is new A1 with private;
17036 -- type T is new A2 with null record;
17038 -- In this case, the full view of T inherits F1 and F2 but the private
17039 -- view inherits only F1
17043 Ancestor : Entity_Id := Scope (C);
17047 if Ancestor = Original_Scope then
17049 elsif Ancestor = Etype (Ancestor) then
17053 Ancestor := Etype (Ancestor);
17057 end Is_Visible_Component;
17059 --------------------------
17060 -- Make_Class_Wide_Type --
17061 --------------------------
17063 procedure Make_Class_Wide_Type (T : Entity_Id) is
17064 CW_Type : Entity_Id;
17066 Next_E : Entity_Id;
17069 if Present (Class_Wide_Type (T)) then
17071 -- The class-wide type is a partially decorated entity created for a
17072 -- unanalyzed tagged type referenced through a limited with clause.
17073 -- When the tagged type is analyzed, its class-wide type needs to be
17074 -- redecorated. Note that we reuse the entity created by Decorate_
17075 -- Tagged_Type in order to preserve all links.
17077 if Materialize_Entity (Class_Wide_Type (T)) then
17078 CW_Type := Class_Wide_Type (T);
17079 Set_Materialize_Entity (CW_Type, False);
17081 -- The class wide type can have been defined by the partial view, in
17082 -- which case everything is already done.
17088 -- Default case, we need to create a new class-wide type
17092 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17095 -- Inherit root type characteristics
17097 CW_Name := Chars (CW_Type);
17098 Next_E := Next_Entity (CW_Type);
17099 Copy_Node (T, CW_Type);
17100 Set_Comes_From_Source (CW_Type, False);
17101 Set_Chars (CW_Type, CW_Name);
17102 Set_Parent (CW_Type, Parent (T));
17103 Set_Next_Entity (CW_Type, Next_E);
17105 -- Ensure we have a new freeze node for the class-wide type. The partial
17106 -- view may have freeze action of its own, requiring a proper freeze
17107 -- node, and the same freeze node cannot be shared between the two
17110 Set_Has_Delayed_Freeze (CW_Type);
17111 Set_Freeze_Node (CW_Type, Empty);
17113 -- Customize the class-wide type: It has no prim. op., it cannot be
17114 -- abstract and its Etype points back to the specific root type.
17116 Set_Ekind (CW_Type, E_Class_Wide_Type);
17117 Set_Is_Tagged_Type (CW_Type, True);
17118 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17119 Set_Is_Abstract_Type (CW_Type, False);
17120 Set_Is_Constrained (CW_Type, False);
17121 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17122 Set_Default_SSO (CW_Type);
17124 if Ekind (T) = E_Class_Wide_Subtype then
17125 Set_Etype (CW_Type, Etype (Base_Type (T)));
17127 Set_Etype (CW_Type, T);
17130 -- If this is the class_wide type of a constrained subtype, it does
17131 -- not have discriminants.
17133 Set_Has_Discriminants (CW_Type,
17134 Has_Discriminants (T) and then not Is_Constrained (T));
17136 Set_Has_Unknown_Discriminants (CW_Type, True);
17137 Set_Class_Wide_Type (T, CW_Type);
17138 Set_Equivalent_Type (CW_Type, Empty);
17140 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17142 Set_Class_Wide_Type (CW_Type, CW_Type);
17143 end Make_Class_Wide_Type;
17149 procedure Make_Index
17151 Related_Nod : Node_Id;
17152 Related_Id : Entity_Id := Empty;
17153 Suffix_Index : Nat := 1;
17154 In_Iter_Schm : Boolean := False)
17158 Def_Id : Entity_Id := Empty;
17159 Found : Boolean := False;
17162 -- For a discrete range used in a constrained array definition and
17163 -- defined by a range, an implicit conversion to the predefined type
17164 -- INTEGER is assumed if each bound is either a numeric literal, a named
17165 -- number, or an attribute, and the type of both bounds (prior to the
17166 -- implicit conversion) is the type universal_integer. Otherwise, both
17167 -- bounds must be of the same discrete type, other than universal
17168 -- integer; this type must be determinable independently of the
17169 -- context, but using the fact that the type must be discrete and that
17170 -- both bounds must have the same type.
17172 -- Character literals also have a universal type in the absence of
17173 -- of additional context, and are resolved to Standard_Character.
17175 if Nkind (N) = N_Range then
17177 -- The index is given by a range constraint. The bounds are known
17178 -- to be of a consistent type.
17180 if not Is_Overloaded (N) then
17183 -- For universal bounds, choose the specific predefined type
17185 if T = Universal_Integer then
17186 T := Standard_Integer;
17188 elsif T = Any_Character then
17189 Ambiguous_Character (Low_Bound (N));
17191 T := Standard_Character;
17194 -- The node may be overloaded because some user-defined operators
17195 -- are available, but if a universal interpretation exists it is
17196 -- also the selected one.
17198 elsif Universal_Interpretation (N) = Universal_Integer then
17199 T := Standard_Integer;
17205 Ind : Interp_Index;
17209 Get_First_Interp (N, Ind, It);
17210 while Present (It.Typ) loop
17211 if Is_Discrete_Type (It.Typ) then
17214 and then not Covers (It.Typ, T)
17215 and then not Covers (T, It.Typ)
17217 Error_Msg_N ("ambiguous bounds in discrete range", N);
17225 Get_Next_Interp (Ind, It);
17228 if T = Any_Type then
17229 Error_Msg_N ("discrete type required for range", N);
17230 Set_Etype (N, Any_Type);
17233 elsif T = Universal_Integer then
17234 T := Standard_Integer;
17239 if not Is_Discrete_Type (T) then
17240 Error_Msg_N ("discrete type required for range", N);
17241 Set_Etype (N, Any_Type);
17245 if Nkind (Low_Bound (N)) = N_Attribute_Reference
17246 and then Attribute_Name (Low_Bound (N)) = Name_First
17247 and then Is_Entity_Name (Prefix (Low_Bound (N)))
17248 and then Is_Type (Entity (Prefix (Low_Bound (N))))
17249 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
17251 -- The type of the index will be the type of the prefix, as long
17252 -- as the upper bound is 'Last of the same type.
17254 Def_Id := Entity (Prefix (Low_Bound (N)));
17256 if Nkind (High_Bound (N)) /= N_Attribute_Reference
17257 or else Attribute_Name (High_Bound (N)) /= Name_Last
17258 or else not Is_Entity_Name (Prefix (High_Bound (N)))
17259 or else Entity (Prefix (High_Bound (N))) /= Def_Id
17266 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
17268 elsif Nkind (N) = N_Subtype_Indication then
17270 -- The index is given by a subtype with a range constraint
17272 T := Base_Type (Entity (Subtype_Mark (N)));
17274 if not Is_Discrete_Type (T) then
17275 Error_Msg_N ("discrete type required for range", N);
17276 Set_Etype (N, Any_Type);
17280 R := Range_Expression (Constraint (N));
17283 Process_Range_Expr_In_Decl
17284 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
17286 elsif Nkind (N) = N_Attribute_Reference then
17288 -- Catch beginner's error (use of attribute other than 'Range)
17290 if Attribute_Name (N) /= Name_Range then
17291 Error_Msg_N ("expect attribute ''Range", N);
17292 Set_Etype (N, Any_Type);
17296 -- If the node denotes the range of a type mark, that is also the
17297 -- resulting type, and we do not need to create an Itype for it.
17299 if Is_Entity_Name (Prefix (N))
17300 and then Comes_From_Source (N)
17301 and then Is_Type (Entity (Prefix (N)))
17302 and then Is_Discrete_Type (Entity (Prefix (N)))
17304 Def_Id := Entity (Prefix (N));
17307 Analyze_And_Resolve (N);
17311 -- If none of the above, must be a subtype. We convert this to a
17312 -- range attribute reference because in the case of declared first
17313 -- named subtypes, the types in the range reference can be different
17314 -- from the type of the entity. A range attribute normalizes the
17315 -- reference and obtains the correct types for the bounds.
17317 -- This transformation is in the nature of an expansion, is only
17318 -- done if expansion is active. In particular, it is not done on
17319 -- formal generic types, because we need to retain the name of the
17320 -- original index for instantiation purposes.
17323 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
17324 Error_Msg_N ("invalid subtype mark in discrete range ", N);
17325 Set_Etype (N, Any_Integer);
17329 -- The type mark may be that of an incomplete type. It is only
17330 -- now that we can get the full view, previous analysis does
17331 -- not look specifically for a type mark.
17333 Set_Entity (N, Get_Full_View (Entity (N)));
17334 Set_Etype (N, Entity (N));
17335 Def_Id := Entity (N);
17337 if not Is_Discrete_Type (Def_Id) then
17338 Error_Msg_N ("discrete type required for index", N);
17339 Set_Etype (N, Any_Type);
17344 if Expander_Active then
17346 Make_Attribute_Reference (Sloc (N),
17347 Attribute_Name => Name_Range,
17348 Prefix => Relocate_Node (N)));
17350 -- The original was a subtype mark that does not freeze. This
17351 -- means that the rewritten version must not freeze either.
17353 Set_Must_Not_Freeze (N);
17354 Set_Must_Not_Freeze (Prefix (N));
17355 Analyze_And_Resolve (N);
17359 -- If expander is inactive, type is legal, nothing else to construct
17366 if not Is_Discrete_Type (T) then
17367 Error_Msg_N ("discrete type required for range", N);
17368 Set_Etype (N, Any_Type);
17371 elsif T = Any_Type then
17372 Set_Etype (N, Any_Type);
17376 -- We will now create the appropriate Itype to describe the range, but
17377 -- first a check. If we originally had a subtype, then we just label
17378 -- the range with this subtype. Not only is there no need to construct
17379 -- a new subtype, but it is wrong to do so for two reasons:
17381 -- 1. A legality concern, if we have a subtype, it must not freeze,
17382 -- and the Itype would cause freezing incorrectly
17384 -- 2. An efficiency concern, if we created an Itype, it would not be
17385 -- recognized as the same type for the purposes of eliminating
17386 -- checks in some circumstances.
17388 -- We signal this case by setting the subtype entity in Def_Id
17390 if No (Def_Id) then
17392 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
17393 Set_Etype (Def_Id, Base_Type (T));
17395 if Is_Signed_Integer_Type (T) then
17396 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
17398 elsif Is_Modular_Integer_Type (T) then
17399 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
17402 Set_Ekind (Def_Id, E_Enumeration_Subtype);
17403 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
17404 Set_First_Literal (Def_Id, First_Literal (T));
17407 Set_Size_Info (Def_Id, (T));
17408 Set_RM_Size (Def_Id, RM_Size (T));
17409 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
17411 Set_Scalar_Range (Def_Id, R);
17412 Conditional_Delay (Def_Id, T);
17414 -- In the subtype indication case, if the immediate parent of the
17415 -- new subtype is non-static, then the subtype we create is non-
17416 -- static, even if its bounds are static.
17418 if Nkind (N) = N_Subtype_Indication
17419 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
17421 Set_Is_Non_Static_Subtype (Def_Id);
17425 -- Final step is to label the index with this constructed type
17427 Set_Etype (N, Def_Id);
17430 ------------------------------
17431 -- Modular_Type_Declaration --
17432 ------------------------------
17434 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17435 Mod_Expr : constant Node_Id := Expression (Def);
17438 procedure Set_Modular_Size (Bits : Int);
17439 -- Sets RM_Size to Bits, and Esize to normal word size above this
17441 ----------------------
17442 -- Set_Modular_Size --
17443 ----------------------
17445 procedure Set_Modular_Size (Bits : Int) is
17447 Set_RM_Size (T, UI_From_Int (Bits));
17452 elsif Bits <= 16 then
17453 Init_Esize (T, 16);
17455 elsif Bits <= 32 then
17456 Init_Esize (T, 32);
17459 Init_Esize (T, System_Max_Binary_Modulus_Power);
17462 if not Non_Binary_Modulus (T)
17463 and then Esize (T) = RM_Size (T)
17465 Set_Is_Known_Valid (T);
17467 end Set_Modular_Size;
17469 -- Start of processing for Modular_Type_Declaration
17472 -- If the mod expression is (exactly) 2 * literal, where literal is
17473 -- 64 or less,then almost certainly the * was meant to be **. Warn.
17475 if Warn_On_Suspicious_Modulus_Value
17476 and then Nkind (Mod_Expr) = N_Op_Multiply
17477 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
17478 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
17479 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
17480 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
17483 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
17486 -- Proceed with analysis of mod expression
17488 Analyze_And_Resolve (Mod_Expr, Any_Integer);
17490 Set_Ekind (T, E_Modular_Integer_Type);
17491 Init_Alignment (T);
17492 Set_Is_Constrained (T);
17494 if not Is_OK_Static_Expression (Mod_Expr) then
17495 Flag_Non_Static_Expr
17496 ("non-static expression used for modular type bound!", Mod_Expr);
17497 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17499 M_Val := Expr_Value (Mod_Expr);
17503 Error_Msg_N ("modulus value must be positive", Mod_Expr);
17504 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17507 if M_Val > 2 ** Standard_Long_Integer_Size then
17508 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
17511 Set_Modulus (T, M_Val);
17513 -- Create bounds for the modular type based on the modulus given in
17514 -- the type declaration and then analyze and resolve those bounds.
17516 Set_Scalar_Range (T,
17517 Make_Range (Sloc (Mod_Expr),
17518 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
17519 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
17521 -- Properly analyze the literals for the range. We do this manually
17522 -- because we can't go calling Resolve, since we are resolving these
17523 -- bounds with the type, and this type is certainly not complete yet.
17525 Set_Etype (Low_Bound (Scalar_Range (T)), T);
17526 Set_Etype (High_Bound (Scalar_Range (T)), T);
17527 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
17528 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
17530 -- Loop through powers of two to find number of bits required
17532 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
17536 if M_Val = 2 ** Bits then
17537 Set_Modular_Size (Bits);
17542 elsif M_Val < 2 ** Bits then
17543 Check_SPARK_Restriction ("modulus should be a power of 2", T);
17544 Set_Non_Binary_Modulus (T);
17546 if Bits > System_Max_Nonbinary_Modulus_Power then
17547 Error_Msg_Uint_1 :=
17548 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
17550 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
17551 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17555 -- In the non-binary case, set size as per RM 13.3(55)
17557 Set_Modular_Size (Bits);
17564 -- If we fall through, then the size exceed System.Max_Binary_Modulus
17565 -- so we just signal an error and set the maximum size.
17567 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
17568 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
17570 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17571 Init_Alignment (T);
17573 end Modular_Type_Declaration;
17575 --------------------------
17576 -- New_Concatenation_Op --
17577 --------------------------
17579 procedure New_Concatenation_Op (Typ : Entity_Id) is
17580 Loc : constant Source_Ptr := Sloc (Typ);
17583 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
17584 -- Create abbreviated declaration for the formal of a predefined
17585 -- Operator 'Op' of type 'Typ'
17587 --------------------
17588 -- Make_Op_Formal --
17589 --------------------
17591 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
17592 Formal : Entity_Id;
17594 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
17595 Set_Etype (Formal, Typ);
17596 Set_Mechanism (Formal, Default_Mechanism);
17598 end Make_Op_Formal;
17600 -- Start of processing for New_Concatenation_Op
17603 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
17605 Set_Ekind (Op, E_Operator);
17606 Set_Scope (Op, Current_Scope);
17607 Set_Etype (Op, Typ);
17608 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
17609 Set_Is_Immediately_Visible (Op);
17610 Set_Is_Intrinsic_Subprogram (Op);
17611 Set_Has_Completion (Op);
17612 Append_Entity (Op, Current_Scope);
17614 Set_Name_Entity_Id (Name_Op_Concat, Op);
17616 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17617 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17618 end New_Concatenation_Op;
17620 -------------------------
17621 -- OK_For_Limited_Init --
17622 -------------------------
17624 -- ???Check all calls of this, and compare the conditions under which it's
17627 function OK_For_Limited_Init
17629 Exp : Node_Id) return Boolean
17632 return Is_CPP_Constructor_Call (Exp)
17633 or else (Ada_Version >= Ada_2005
17634 and then not Debug_Flag_Dot_L
17635 and then OK_For_Limited_Init_In_05 (Typ, Exp));
17636 end OK_For_Limited_Init;
17638 -------------------------------
17639 -- OK_For_Limited_Init_In_05 --
17640 -------------------------------
17642 function OK_For_Limited_Init_In_05
17644 Exp : Node_Id) return Boolean
17647 -- An object of a limited interface type can be initialized with any
17648 -- expression of a nonlimited descendant type.
17650 if Is_Class_Wide_Type (Typ)
17651 and then Is_Limited_Interface (Typ)
17652 and then not Is_Limited_Type (Etype (Exp))
17657 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
17658 -- case of limited aggregates (including extension aggregates), and
17659 -- function calls. The function call may have been given in prefixed
17660 -- notation, in which case the original node is an indexed component.
17661 -- If the function is parameterless, the original node was an explicit
17662 -- dereference. The function may also be parameterless, in which case
17663 -- the source node is just an identifier.
17665 case Nkind (Original_Node (Exp)) is
17666 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
17669 when N_Identifier =>
17670 return Present (Entity (Original_Node (Exp)))
17671 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
17673 when N_Qualified_Expression =>
17675 OK_For_Limited_Init_In_05
17676 (Typ, Expression (Original_Node (Exp)));
17678 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
17679 -- with a function call, the expander has rewritten the call into an
17680 -- N_Type_Conversion node to force displacement of the pointer to
17681 -- reference the component containing the secondary dispatch table.
17682 -- Otherwise a type conversion is not a legal context.
17683 -- A return statement for a build-in-place function returning a
17684 -- synchronized type also introduces an unchecked conversion.
17686 when N_Type_Conversion |
17687 N_Unchecked_Type_Conversion =>
17688 return not Comes_From_Source (Exp)
17690 OK_For_Limited_Init_In_05
17691 (Typ, Expression (Original_Node (Exp)));
17693 when N_Indexed_Component |
17694 N_Selected_Component |
17695 N_Explicit_Dereference =>
17696 return Nkind (Exp) = N_Function_Call;
17698 -- A use of 'Input is a function call, hence allowed. Normally the
17699 -- attribute will be changed to a call, but the attribute by itself
17700 -- can occur with -gnatc.
17702 when N_Attribute_Reference =>
17703 return Attribute_Name (Original_Node (Exp)) = Name_Input;
17705 -- For a case expression, all dependent expressions must be legal
17707 when N_Case_Expression =>
17712 Alt := First (Alternatives (Original_Node (Exp)));
17713 while Present (Alt) loop
17714 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
17724 -- For an if expression, all dependent expressions must be legal
17726 when N_If_Expression =>
17728 Then_Expr : constant Node_Id :=
17729 Next (First (Expressions (Original_Node (Exp))));
17730 Else_Expr : constant Node_Id := Next (Then_Expr);
17732 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
17734 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
17740 end OK_For_Limited_Init_In_05;
17742 -------------------------------------------
17743 -- Ordinary_Fixed_Point_Type_Declaration --
17744 -------------------------------------------
17746 procedure Ordinary_Fixed_Point_Type_Declaration
17750 Loc : constant Source_Ptr := Sloc (Def);
17751 Delta_Expr : constant Node_Id := Delta_Expression (Def);
17752 RRS : constant Node_Id := Real_Range_Specification (Def);
17753 Implicit_Base : Entity_Id;
17760 Check_Restriction (No_Fixed_Point, Def);
17762 -- Create implicit base type
17765 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
17766 Set_Etype (Implicit_Base, Implicit_Base);
17768 -- Analyze and process delta expression
17770 Analyze_And_Resolve (Delta_Expr, Any_Real);
17772 Check_Delta_Expression (Delta_Expr);
17773 Delta_Val := Expr_Value_R (Delta_Expr);
17775 Set_Delta_Value (Implicit_Base, Delta_Val);
17777 -- Compute default small from given delta, which is the largest power
17778 -- of two that does not exceed the given delta value.
17788 if Delta_Val < Ureal_1 then
17789 while Delta_Val < Tmp loop
17790 Tmp := Tmp / Ureal_2;
17791 Scale := Scale + 1;
17796 Tmp := Tmp * Ureal_2;
17797 exit when Tmp > Delta_Val;
17798 Scale := Scale - 1;
17802 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
17805 Set_Small_Value (Implicit_Base, Small_Val);
17807 -- If no range was given, set a dummy range
17809 if RRS <= Empty_Or_Error then
17810 Low_Val := -Small_Val;
17811 High_Val := Small_Val;
17813 -- Otherwise analyze and process given range
17817 Low : constant Node_Id := Low_Bound (RRS);
17818 High : constant Node_Id := High_Bound (RRS);
17821 Analyze_And_Resolve (Low, Any_Real);
17822 Analyze_And_Resolve (High, Any_Real);
17823 Check_Real_Bound (Low);
17824 Check_Real_Bound (High);
17826 -- Obtain and set the range
17828 Low_Val := Expr_Value_R (Low);
17829 High_Val := Expr_Value_R (High);
17831 if Low_Val > High_Val then
17832 Error_Msg_NE ("??fixed point type& has null range", Def, T);
17837 -- The range for both the implicit base and the declared first subtype
17838 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
17839 -- set a temporary range in place. Note that the bounds of the base
17840 -- type will be widened to be symmetrical and to fill the available
17841 -- bits when the type is frozen.
17843 -- We could do this with all discrete types, and probably should, but
17844 -- we absolutely have to do it for fixed-point, since the end-points
17845 -- of the range and the size are determined by the small value, which
17846 -- could be reset before the freeze point.
17848 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
17849 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
17851 -- Complete definition of first subtype
17853 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
17854 Set_Etype (T, Implicit_Base);
17855 Init_Size_Align (T);
17856 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
17857 Set_Small_Value (T, Small_Val);
17858 Set_Delta_Value (T, Delta_Val);
17859 Set_Is_Constrained (T);
17861 end Ordinary_Fixed_Point_Type_Declaration;
17863 ----------------------------------------
17864 -- Prepare_Private_Subtype_Completion --
17865 ----------------------------------------
17867 procedure Prepare_Private_Subtype_Completion
17869 Related_Nod : Node_Id)
17871 Id_B : constant Entity_Id := Base_Type (Id);
17872 Full_B : constant Entity_Id := Full_View (Id_B);
17876 if Present (Full_B) then
17878 -- The Base_Type is already completed, we can complete the subtype
17879 -- now. We have to create a new entity with the same name, Thus we
17880 -- can't use Create_Itype.
17882 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
17883 Set_Is_Itype (Full);
17884 Set_Associated_Node_For_Itype (Full, Related_Nod);
17885 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
17888 -- The parent subtype may be private, but the base might not, in some
17889 -- nested instances. In that case, the subtype does not need to be
17890 -- exchanged. It would still be nice to make private subtypes and their
17891 -- bases consistent at all times ???
17893 if Is_Private_Type (Id_B) then
17894 Append_Elmt (Id, Private_Dependents (Id_B));
17896 end Prepare_Private_Subtype_Completion;
17898 ---------------------------
17899 -- Process_Discriminants --
17900 ---------------------------
17902 procedure Process_Discriminants
17904 Prev : Entity_Id := Empty)
17906 Elist : constant Elist_Id := New_Elmt_List;
17909 Discr_Number : Uint;
17910 Discr_Type : Entity_Id;
17911 Default_Present : Boolean := False;
17912 Default_Not_Present : Boolean := False;
17915 -- A composite type other than an array type can have discriminants.
17916 -- On entry, the current scope is the composite type.
17918 -- The discriminants are initially entered into the scope of the type
17919 -- via Enter_Name with the default Ekind of E_Void to prevent premature
17920 -- use, as explained at the end of this procedure.
17922 Discr := First (Discriminant_Specifications (N));
17923 while Present (Discr) loop
17924 Enter_Name (Defining_Identifier (Discr));
17926 -- For navigation purposes we add a reference to the discriminant
17927 -- in the entity for the type. If the current declaration is a
17928 -- completion, place references on the partial view. Otherwise the
17929 -- type is the current scope.
17931 if Present (Prev) then
17933 -- The references go on the partial view, if present. If the
17934 -- partial view has discriminants, the references have been
17935 -- generated already.
17937 if not Has_Discriminants (Prev) then
17938 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17942 (Current_Scope, Defining_Identifier (Discr), 'd');
17945 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17946 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17948 -- Ada 2005 (AI-254)
17950 if Present (Access_To_Subprogram_Definition
17951 (Discriminant_Type (Discr)))
17952 and then Protected_Present (Access_To_Subprogram_Definition
17953 (Discriminant_Type (Discr)))
17956 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17960 Find_Type (Discriminant_Type (Discr));
17961 Discr_Type := Etype (Discriminant_Type (Discr));
17963 if Error_Posted (Discriminant_Type (Discr)) then
17964 Discr_Type := Any_Type;
17968 if Is_Access_Type (Discr_Type) then
17970 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17973 if Ada_Version < Ada_2005 then
17974 Check_Access_Discriminant_Requires_Limited
17975 (Discr, Discriminant_Type (Discr));
17978 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17980 ("(Ada 83) access discriminant not allowed", Discr);
17983 elsif not Is_Discrete_Type (Discr_Type) then
17984 Error_Msg_N ("discriminants must have a discrete or access type",
17985 Discriminant_Type (Discr));
17988 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17990 -- If a discriminant specification includes the assignment compound
17991 -- delimiter followed by an expression, the expression is the default
17992 -- expression of the discriminant; the default expression must be of
17993 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17994 -- a default expression, we do the special preanalysis, since this
17995 -- expression does not freeze (see "Handling of Default and Per-
17996 -- Object Expressions" in spec of package Sem).
17998 if Present (Expression (Discr)) then
17999 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18001 if Nkind (N) = N_Formal_Type_Declaration then
18003 ("discriminant defaults not allowed for formal type",
18004 Expression (Discr));
18006 -- Flag an error for a tagged type with defaulted discriminants,
18007 -- excluding limited tagged types when compiling for Ada 2012
18008 -- (see AI05-0214).
18010 elsif Is_Tagged_Type (Current_Scope)
18011 and then (not Is_Limited_Type (Current_Scope)
18012 or else Ada_Version < Ada_2012)
18013 and then Comes_From_Source (N)
18015 -- Note: see similar test in Check_Or_Process_Discriminants, to
18016 -- handle the (illegal) case of the completion of an untagged
18017 -- view with discriminants with defaults by a tagged full view.
18018 -- We skip the check if Discr does not come from source, to
18019 -- account for the case of an untagged derived type providing
18020 -- defaults for a renamed discriminant from a private untagged
18021 -- ancestor with a tagged full view (ACATS B460006).
18023 if Ada_Version >= Ada_2012 then
18025 ("discriminants of nonlimited tagged type cannot have"
18027 Expression (Discr));
18030 ("discriminants of tagged type cannot have defaults",
18031 Expression (Discr));
18035 Default_Present := True;
18036 Append_Elmt (Expression (Discr), Elist);
18038 -- Tag the defining identifiers for the discriminants with
18039 -- their corresponding default expressions from the tree.
18041 Set_Discriminant_Default_Value
18042 (Defining_Identifier (Discr), Expression (Discr));
18046 Default_Not_Present := True;
18049 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
18050 -- Discr_Type but with the null-exclusion attribute
18052 if Ada_Version >= Ada_2005 then
18054 -- Ada 2005 (AI-231): Static checks
18056 if Can_Never_Be_Null (Discr_Type) then
18057 Null_Exclusion_Static_Checks (Discr);
18059 elsif Is_Access_Type (Discr_Type)
18060 and then Null_Exclusion_Present (Discr)
18062 -- No need to check itypes because in their case this check
18063 -- was done at their point of creation
18065 and then not Is_Itype (Discr_Type)
18067 if Can_Never_Be_Null (Discr_Type) then
18069 ("`NOT NULL` not allowed (& already excludes null)",
18074 Set_Etype (Defining_Identifier (Discr),
18075 Create_Null_Excluding_Itype
18077 Related_Nod => Discr));
18079 -- Check for improper null exclusion if the type is otherwise
18080 -- legal for a discriminant.
18082 elsif Null_Exclusion_Present (Discr)
18083 and then Is_Discrete_Type (Discr_Type)
18086 ("null exclusion can only apply to an access type", Discr);
18089 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18090 -- can't have defaults. Synchronized types, or types that are
18091 -- explicitly limited are fine, but special tests apply to derived
18092 -- types in generics: in a generic body we have to assume the
18093 -- worst, and therefore defaults are not allowed if the parent is
18094 -- a generic formal private type (see ACATS B370001).
18096 if Is_Access_Type (Discr_Type) and then Default_Present then
18097 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18098 or else Is_Limited_Record (Current_Scope)
18099 or else Is_Concurrent_Type (Current_Scope)
18100 or else Is_Concurrent_Record_Type (Current_Scope)
18101 or else Ekind (Current_Scope) = E_Limited_Private_Type
18103 if not Is_Derived_Type (Current_Scope)
18104 or else not Is_Generic_Type (Etype (Current_Scope))
18105 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18106 or else Limited_Present
18107 (Type_Definition (Parent (Current_Scope)))
18112 Error_Msg_N ("access discriminants of nonlimited types",
18113 Expression (Discr));
18114 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18117 elsif Present (Expression (Discr)) then
18119 ("(Ada 2005) access discriminants of nonlimited types",
18120 Expression (Discr));
18121 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18126 -- A discriminant cannot be volatile. This check is only relevant
18127 -- when SPARK_Mode is on as it is not standard Ada legality rule
18128 -- (SPARK RM 7.1.3(6)).
18131 and then Is_SPARK_Volatile (Defining_Identifier (Discr))
18133 Error_Msg_N ("discriminant cannot be volatile", Discr);
18139 -- An element list consisting of the default expressions of the
18140 -- discriminants is constructed in the above loop and used to set
18141 -- the Discriminant_Constraint attribute for the type. If an object
18142 -- is declared of this (record or task) type without any explicit
18143 -- discriminant constraint given, this element list will form the
18144 -- actual parameters for the corresponding initialization procedure
18147 Set_Discriminant_Constraint (Current_Scope, Elist);
18148 Set_Stored_Constraint (Current_Scope, No_Elist);
18150 -- Default expressions must be provided either for all or for none
18151 -- of the discriminants of a discriminant part. (RM 3.7.1)
18153 if Default_Present and then Default_Not_Present then
18155 ("incomplete specification of defaults for discriminants", N);
18158 -- The use of the name of a discriminant is not allowed in default
18159 -- expressions of a discriminant part if the specification of the
18160 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
18162 -- To detect this, the discriminant names are entered initially with an
18163 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
18164 -- attempt to use a void entity (for example in an expression that is
18165 -- type-checked) produces the error message: premature usage. Now after
18166 -- completing the semantic analysis of the discriminant part, we can set
18167 -- the Ekind of all the discriminants appropriately.
18169 Discr := First (Discriminant_Specifications (N));
18170 Discr_Number := Uint_1;
18171 while Present (Discr) loop
18172 Id := Defining_Identifier (Discr);
18173 Set_Ekind (Id, E_Discriminant);
18174 Init_Component_Location (Id);
18176 Set_Discriminant_Number (Id, Discr_Number);
18178 -- Make sure this is always set, even in illegal programs
18180 Set_Corresponding_Discriminant (Id, Empty);
18182 -- Initialize the Original_Record_Component to the entity itself.
18183 -- Inherit_Components will propagate the right value to
18184 -- discriminants in derived record types.
18186 Set_Original_Record_Component (Id, Id);
18188 -- Create the discriminal for the discriminant
18190 Build_Discriminal (Id);
18193 Discr_Number := Discr_Number + 1;
18196 Set_Has_Discriminants (Current_Scope);
18197 end Process_Discriminants;
18199 -----------------------
18200 -- Process_Full_View --
18201 -----------------------
18203 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
18204 Priv_Parent : Entity_Id;
18205 Full_Parent : Entity_Id;
18206 Full_Indic : Node_Id;
18208 procedure Collect_Implemented_Interfaces
18210 Ifaces : Elist_Id);
18211 -- Ada 2005: Gather all the interfaces that Typ directly or
18212 -- inherently implements. Duplicate entries are not added to
18213 -- the list Ifaces.
18215 ------------------------------------
18216 -- Collect_Implemented_Interfaces --
18217 ------------------------------------
18219 procedure Collect_Implemented_Interfaces
18224 Iface_Elmt : Elmt_Id;
18227 -- Abstract interfaces are only associated with tagged record types
18229 if not Is_Tagged_Type (Typ)
18230 or else not Is_Record_Type (Typ)
18235 -- Recursively climb to the ancestors
18237 if Etype (Typ) /= Typ
18239 -- Protect the frontend against wrong cyclic declarations like:
18241 -- type B is new A with private;
18242 -- type C is new A with private;
18244 -- type B is new C with null record;
18245 -- type C is new B with null record;
18247 and then Etype (Typ) /= Priv_T
18248 and then Etype (Typ) /= Full_T
18250 -- Keep separate the management of private type declarations
18252 if Ekind (Typ) = E_Record_Type_With_Private then
18254 -- Handle the following illegal usage:
18255 -- type Private_Type is tagged private;
18257 -- type Private_Type is new Type_Implementing_Iface;
18259 if Present (Full_View (Typ))
18260 and then Etype (Typ) /= Full_View (Typ)
18262 if Is_Interface (Etype (Typ)) then
18263 Append_Unique_Elmt (Etype (Typ), Ifaces);
18266 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18269 -- Non-private types
18272 if Is_Interface (Etype (Typ)) then
18273 Append_Unique_Elmt (Etype (Typ), Ifaces);
18276 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18280 -- Handle entities in the list of abstract interfaces
18282 if Present (Interfaces (Typ)) then
18283 Iface_Elmt := First_Elmt (Interfaces (Typ));
18284 while Present (Iface_Elmt) loop
18285 Iface := Node (Iface_Elmt);
18287 pragma Assert (Is_Interface (Iface));
18289 if not Contain_Interface (Iface, Ifaces) then
18290 Append_Elmt (Iface, Ifaces);
18291 Collect_Implemented_Interfaces (Iface, Ifaces);
18294 Next_Elmt (Iface_Elmt);
18297 end Collect_Implemented_Interfaces;
18299 -- Start of processing for Process_Full_View
18302 -- First some sanity checks that must be done after semantic
18303 -- decoration of the full view and thus cannot be placed with other
18304 -- similar checks in Find_Type_Name
18306 if not Is_Limited_Type (Priv_T)
18307 and then (Is_Limited_Type (Full_T)
18308 or else Is_Limited_Composite (Full_T))
18310 if In_Instance then
18314 ("completion of nonlimited type cannot be limited", Full_T);
18315 Explain_Limited_Type (Full_T, Full_T);
18318 elsif Is_Abstract_Type (Full_T)
18319 and then not Is_Abstract_Type (Priv_T)
18322 ("completion of nonabstract type cannot be abstract", Full_T);
18324 elsif Is_Tagged_Type (Priv_T)
18325 and then Is_Limited_Type (Priv_T)
18326 and then not Is_Limited_Type (Full_T)
18328 -- If pragma CPP_Class was applied to the private declaration
18329 -- propagate the limitedness to the full-view
18331 if Is_CPP_Class (Priv_T) then
18332 Set_Is_Limited_Record (Full_T);
18334 -- GNAT allow its own definition of Limited_Controlled to disobey
18335 -- this rule in order in ease the implementation. This test is safe
18336 -- because Root_Controlled is defined in a child of System that
18337 -- normal programs are not supposed to use.
18339 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
18340 Set_Is_Limited_Composite (Full_T);
18343 ("completion of limited tagged type must be limited", Full_T);
18346 elsif Is_Generic_Type (Priv_T) then
18347 Error_Msg_N ("generic type cannot have a completion", Full_T);
18350 -- Check that ancestor interfaces of private and full views are
18351 -- consistent. We omit this check for synchronized types because
18352 -- they are performed on the corresponding record type when frozen.
18354 if Ada_Version >= Ada_2005
18355 and then Is_Tagged_Type (Priv_T)
18356 and then Is_Tagged_Type (Full_T)
18357 and then not Is_Concurrent_Type (Full_T)
18361 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
18362 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
18365 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
18366 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
18368 -- Ada 2005 (AI-251): The partial view shall be a descendant of
18369 -- an interface type if and only if the full type is descendant
18370 -- of the interface type (AARM 7.3 (7.3/2)).
18372 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
18374 if Present (Iface) then
18376 ("interface in partial view& not implemented by full type "
18377 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18380 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
18382 if Present (Iface) then
18384 ("interface & not implemented by partial view "
18385 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18390 if Is_Tagged_Type (Priv_T)
18391 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18392 and then Is_Derived_Type (Full_T)
18394 Priv_Parent := Etype (Priv_T);
18396 -- The full view of a private extension may have been transformed
18397 -- into an unconstrained derived type declaration and a subtype
18398 -- declaration (see build_derived_record_type for details).
18400 if Nkind (N) = N_Subtype_Declaration then
18401 Full_Indic := Subtype_Indication (N);
18402 Full_Parent := Etype (Base_Type (Full_T));
18404 Full_Indic := Subtype_Indication (Type_Definition (N));
18405 Full_Parent := Etype (Full_T);
18408 -- Check that the parent type of the full type is a descendant of
18409 -- the ancestor subtype given in the private extension. If either
18410 -- entity has an Etype equal to Any_Type then we had some previous
18411 -- error situation [7.3(8)].
18413 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
18416 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
18417 -- any order. Therefore we don't have to check that its parent must
18418 -- be a descendant of the parent of the private type declaration.
18420 elsif Is_Interface (Priv_Parent)
18421 and then Is_Interface (Full_Parent)
18425 -- Ada 2005 (AI-251): If the parent of the private type declaration
18426 -- is an interface there is no need to check that it is an ancestor
18427 -- of the associated full type declaration. The required tests for
18428 -- this case are performed by Build_Derived_Record_Type.
18430 elsif not Is_Interface (Base_Type (Priv_Parent))
18431 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
18434 ("parent of full type must descend from parent"
18435 & " of private extension", Full_Indic);
18437 -- First check a formal restriction, and then proceed with checking
18438 -- Ada rules. Since the formal restriction is not a serious error, we
18439 -- don't prevent further error detection for this check, hence the
18444 -- In formal mode, when completing a private extension the type
18445 -- named in the private part must be exactly the same as that
18446 -- named in the visible part.
18448 if Priv_Parent /= Full_Parent then
18449 Error_Msg_Name_1 := Chars (Priv_Parent);
18450 Check_SPARK_Restriction ("% expected", Full_Indic);
18453 -- Check the rules of 7.3(10): if the private extension inherits
18454 -- known discriminants, then the full type must also inherit those
18455 -- discriminants from the same (ancestor) type, and the parent
18456 -- subtype of the full type must be constrained if and only if
18457 -- the ancestor subtype of the private extension is constrained.
18459 if No (Discriminant_Specifications (Parent (Priv_T)))
18460 and then not Has_Unknown_Discriminants (Priv_T)
18461 and then Has_Discriminants (Base_Type (Priv_Parent))
18464 Priv_Indic : constant Node_Id :=
18465 Subtype_Indication (Parent (Priv_T));
18467 Priv_Constr : constant Boolean :=
18468 Is_Constrained (Priv_Parent)
18470 Nkind (Priv_Indic) = N_Subtype_Indication
18472 Is_Constrained (Entity (Priv_Indic));
18474 Full_Constr : constant Boolean :=
18475 Is_Constrained (Full_Parent)
18477 Nkind (Full_Indic) = N_Subtype_Indication
18479 Is_Constrained (Entity (Full_Indic));
18481 Priv_Discr : Entity_Id;
18482 Full_Discr : Entity_Id;
18485 Priv_Discr := First_Discriminant (Priv_Parent);
18486 Full_Discr := First_Discriminant (Full_Parent);
18487 while Present (Priv_Discr) and then Present (Full_Discr) loop
18488 if Original_Record_Component (Priv_Discr) =
18489 Original_Record_Component (Full_Discr)
18491 Corresponding_Discriminant (Priv_Discr) =
18492 Corresponding_Discriminant (Full_Discr)
18499 Next_Discriminant (Priv_Discr);
18500 Next_Discriminant (Full_Discr);
18503 if Present (Priv_Discr) or else Present (Full_Discr) then
18505 ("full view must inherit discriminants of the parent"
18506 & " type used in the private extension", Full_Indic);
18508 elsif Priv_Constr and then not Full_Constr then
18510 ("parent subtype of full type must be constrained",
18513 elsif Full_Constr and then not Priv_Constr then
18515 ("parent subtype of full type must be unconstrained",
18520 -- Check the rules of 7.3(12): if a partial view has neither
18521 -- known or unknown discriminants, then the full type
18522 -- declaration shall define a definite subtype.
18524 elsif not Has_Unknown_Discriminants (Priv_T)
18525 and then not Has_Discriminants (Priv_T)
18526 and then not Is_Constrained (Full_T)
18529 ("full view must define a constrained type if partial view"
18530 & " has no discriminants", Full_T);
18533 -- ??????? Do we implement the following properly ?????
18534 -- If the ancestor subtype of a private extension has constrained
18535 -- discriminants, then the parent subtype of the full view shall
18536 -- impose a statically matching constraint on those discriminants
18541 -- For untagged types, verify that a type without discriminants is
18542 -- not completed with an unconstrained type. A separate error message
18543 -- is produced if the full type has defaulted discriminants.
18545 if not Is_Indefinite_Subtype (Priv_T)
18546 and then Is_Indefinite_Subtype (Full_T)
18548 Error_Msg_Sloc := Sloc (Parent (Priv_T));
18550 ("full view of& not compatible with declaration#",
18553 if not Is_Tagged_Type (Full_T) then
18555 ("\one is constrained, the other unconstrained", Full_T);
18560 -- AI-419: verify that the use of "limited" is consistent
18563 Orig_Decl : constant Node_Id := Original_Node (N);
18566 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18567 and then not Limited_Present (Parent (Priv_T))
18568 and then not Synchronized_Present (Parent (Priv_T))
18569 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
18571 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
18572 and then Limited_Present (Type_Definition (Orig_Decl))
18575 ("full view of non-limited extension cannot be limited", N);
18579 -- Ada 2005 (AI-443): A synchronized private extension must be
18580 -- completed by a task or protected type.
18582 if Ada_Version >= Ada_2005
18583 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18584 and then Synchronized_Present (Parent (Priv_T))
18585 and then not Is_Concurrent_Type (Full_T)
18587 Error_Msg_N ("full view of synchronized extension must " &
18588 "be synchronized type", N);
18591 -- Ada 2005 AI-363: if the full view has discriminants with
18592 -- defaults, it is illegal to declare constrained access subtypes
18593 -- whose designated type is the current type. This allows objects
18594 -- of the type that are declared in the heap to be unconstrained.
18596 if not Has_Unknown_Discriminants (Priv_T)
18597 and then not Has_Discriminants (Priv_T)
18598 and then Has_Discriminants (Full_T)
18600 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
18602 Set_Has_Constrained_Partial_View (Full_T);
18603 Set_Has_Constrained_Partial_View (Priv_T);
18606 -- Create a full declaration for all its subtypes recorded in
18607 -- Private_Dependents and swap them similarly to the base type. These
18608 -- are subtypes that have been define before the full declaration of
18609 -- the private type. We also swap the entry in Private_Dependents list
18610 -- so we can properly restore the private view on exit from the scope.
18613 Priv_Elmt : Elmt_Id;
18614 Priv_Scop : Entity_Id;
18619 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
18620 while Present (Priv_Elmt) loop
18621 Priv := Node (Priv_Elmt);
18622 Priv_Scop := Scope (Priv);
18624 if Ekind_In (Priv, E_Private_Subtype,
18625 E_Limited_Private_Subtype,
18626 E_Record_Subtype_With_Private)
18628 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
18629 Set_Is_Itype (Full);
18630 Set_Parent (Full, Parent (Priv));
18631 Set_Associated_Node_For_Itype (Full, N);
18633 -- Now we need to complete the private subtype, but since the
18634 -- base type has already been swapped, we must also swap the
18635 -- subtypes (and thus, reverse the arguments in the call to
18636 -- Complete_Private_Subtype). Also note that we may need to
18637 -- re-establish the scope of the private subtype.
18639 Copy_And_Swap (Priv, Full);
18641 if not In_Open_Scopes (Priv_Scop) then
18642 Push_Scope (Priv_Scop);
18645 -- Reset Priv_Scop to Empty to indicate no scope was pushed
18647 Priv_Scop := Empty;
18650 Complete_Private_Subtype (Full, Priv, Full_T, N);
18652 if Present (Priv_Scop) then
18656 Replace_Elmt (Priv_Elmt, Full);
18659 Next_Elmt (Priv_Elmt);
18663 -- If the private view was tagged, copy the new primitive operations
18664 -- from the private view to the full view.
18666 if Is_Tagged_Type (Full_T) then
18668 Disp_Typ : Entity_Id;
18669 Full_List : Elist_Id;
18671 Prim_Elmt : Elmt_Id;
18672 Priv_List : Elist_Id;
18676 L : Elist_Id) return Boolean;
18677 -- Determine whether list L contains element E
18685 L : Elist_Id) return Boolean
18687 List_Elmt : Elmt_Id;
18690 List_Elmt := First_Elmt (L);
18691 while Present (List_Elmt) loop
18692 if Node (List_Elmt) = E then
18696 Next_Elmt (List_Elmt);
18702 -- Start of processing
18705 if Is_Tagged_Type (Priv_T) then
18706 Priv_List := Primitive_Operations (Priv_T);
18707 Prim_Elmt := First_Elmt (Priv_List);
18709 -- In the case of a concurrent type completing a private tagged
18710 -- type, primitives may have been declared in between the two
18711 -- views. These subprograms need to be wrapped the same way
18712 -- entries and protected procedures are handled because they
18713 -- cannot be directly shared by the two views.
18715 if Is_Concurrent_Type (Full_T) then
18717 Conc_Typ : constant Entity_Id :=
18718 Corresponding_Record_Type (Full_T);
18719 Curr_Nod : Node_Id := Parent (Conc_Typ);
18720 Wrap_Spec : Node_Id;
18723 while Present (Prim_Elmt) loop
18724 Prim := Node (Prim_Elmt);
18726 if Comes_From_Source (Prim)
18727 and then not Is_Abstract_Subprogram (Prim)
18730 Make_Subprogram_Declaration (Sloc (Prim),
18734 Obj_Typ => Conc_Typ,
18736 Parameter_Specifications (
18739 Insert_After (Curr_Nod, Wrap_Spec);
18740 Curr_Nod := Wrap_Spec;
18742 Analyze (Wrap_Spec);
18745 Next_Elmt (Prim_Elmt);
18751 -- For non-concurrent types, transfer explicit primitives, but
18752 -- omit those inherited from the parent of the private view
18753 -- since they will be re-inherited later on.
18756 Full_List := Primitive_Operations (Full_T);
18758 while Present (Prim_Elmt) loop
18759 Prim := Node (Prim_Elmt);
18761 if Comes_From_Source (Prim)
18762 and then not Contains (Prim, Full_List)
18764 Append_Elmt (Prim, Full_List);
18767 Next_Elmt (Prim_Elmt);
18771 -- Untagged private view
18774 Full_List := Primitive_Operations (Full_T);
18776 -- In this case the partial view is untagged, so here we locate
18777 -- all of the earlier primitives that need to be treated as
18778 -- dispatching (those that appear between the two views). Note
18779 -- that these additional operations must all be new operations
18780 -- (any earlier operations that override inherited operations
18781 -- of the full view will already have been inserted in the
18782 -- primitives list, marked by Check_Operation_From_Private_View
18783 -- as dispatching. Note that implicit "/=" operators are
18784 -- excluded from being added to the primitives list since they
18785 -- shouldn't be treated as dispatching (tagged "/=" is handled
18788 Prim := Next_Entity (Full_T);
18789 while Present (Prim) and then Prim /= Priv_T loop
18790 if Ekind_In (Prim, E_Procedure, E_Function) then
18791 Disp_Typ := Find_Dispatching_Type (Prim);
18793 if Disp_Typ = Full_T
18794 and then (Chars (Prim) /= Name_Op_Ne
18795 or else Comes_From_Source (Prim))
18797 Check_Controlling_Formals (Full_T, Prim);
18799 if not Is_Dispatching_Operation (Prim) then
18800 Append_Elmt (Prim, Full_List);
18801 Set_Is_Dispatching_Operation (Prim, True);
18802 Set_DT_Position (Prim, No_Uint);
18805 elsif Is_Dispatching_Operation (Prim)
18806 and then Disp_Typ /= Full_T
18809 -- Verify that it is not otherwise controlled by a
18810 -- formal or a return value of type T.
18812 Check_Controlling_Formals (Disp_Typ, Prim);
18816 Next_Entity (Prim);
18820 -- For the tagged case, the two views can share the same primitive
18821 -- operations list and the same class-wide type. Update attributes
18822 -- of the class-wide type which depend on the full declaration.
18824 if Is_Tagged_Type (Priv_T) then
18825 Set_Direct_Primitive_Operations (Priv_T, Full_List);
18826 Set_Class_Wide_Type
18827 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
18829 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
18831 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
18836 -- Ada 2005 AI 161: Check preelaborable initialization consistency
18838 if Known_To_Have_Preelab_Init (Priv_T) then
18840 -- Case where there is a pragma Preelaborable_Initialization. We
18841 -- always allow this in predefined units, which is cheating a bit,
18842 -- but it means we don't have to struggle to meet the requirements in
18843 -- the RM for having Preelaborable Initialization. Otherwise we
18844 -- require that the type meets the RM rules. But we can't check that
18845 -- yet, because of the rule about overriding Initialize, so we simply
18846 -- set a flag that will be checked at freeze time.
18848 if not In_Predefined_Unit (Full_T) then
18849 Set_Must_Have_Preelab_Init (Full_T);
18853 -- If pragma CPP_Class was applied to the private type declaration,
18854 -- propagate it now to the full type declaration.
18856 if Is_CPP_Class (Priv_T) then
18857 Set_Is_CPP_Class (Full_T);
18858 Set_Convention (Full_T, Convention_CPP);
18860 -- Check that components of imported CPP types do not have default
18863 Check_CPP_Type_Has_No_Defaults (Full_T);
18866 -- If the private view has user specified stream attributes, then so has
18869 -- Why the test, how could these flags be already set in Full_T ???
18871 if Has_Specified_Stream_Read (Priv_T) then
18872 Set_Has_Specified_Stream_Read (Full_T);
18875 if Has_Specified_Stream_Write (Priv_T) then
18876 Set_Has_Specified_Stream_Write (Full_T);
18879 if Has_Specified_Stream_Input (Priv_T) then
18880 Set_Has_Specified_Stream_Input (Full_T);
18883 if Has_Specified_Stream_Output (Priv_T) then
18884 Set_Has_Specified_Stream_Output (Full_T);
18887 -- Propagate invariants to full type
18889 if Has_Invariants (Priv_T) then
18890 Set_Has_Invariants (Full_T);
18891 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
18894 if Has_Inheritable_Invariants (Priv_T) then
18895 Set_Has_Inheritable_Invariants (Full_T);
18898 -- Propagate predicates to full type, and predicate function if already
18899 -- defined. It is not clear that this can actually happen? the partial
18900 -- view cannot be frozen yet, and the predicate function has not been
18901 -- built. Still it is a cheap check and seems safer to make it.
18903 if Has_Predicates (Priv_T) then
18904 if Present (Predicate_Function (Priv_T)) then
18905 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
18908 Set_Has_Predicates (Full_T);
18910 end Process_Full_View;
18912 -----------------------------------
18913 -- Process_Incomplete_Dependents --
18914 -----------------------------------
18916 procedure Process_Incomplete_Dependents
18918 Full_T : Entity_Id;
18921 Inc_Elmt : Elmt_Id;
18922 Priv_Dep : Entity_Id;
18923 New_Subt : Entity_Id;
18925 Disc_Constraint : Elist_Id;
18928 if No (Private_Dependents (Inc_T)) then
18932 -- Itypes that may be generated by the completion of an incomplete
18933 -- subtype are not used by the back-end and not attached to the tree.
18934 -- They are created only for constraint-checking purposes.
18936 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
18937 while Present (Inc_Elmt) loop
18938 Priv_Dep := Node (Inc_Elmt);
18940 if Ekind (Priv_Dep) = E_Subprogram_Type then
18942 -- An Access_To_Subprogram type may have a return type or a
18943 -- parameter type that is incomplete. Replace with the full view.
18945 if Etype (Priv_Dep) = Inc_T then
18946 Set_Etype (Priv_Dep, Full_T);
18950 Formal : Entity_Id;
18953 Formal := First_Formal (Priv_Dep);
18954 while Present (Formal) loop
18955 if Etype (Formal) = Inc_T then
18956 Set_Etype (Formal, Full_T);
18959 Next_Formal (Formal);
18963 elsif Is_Overloadable (Priv_Dep) then
18965 -- If a subprogram in the incomplete dependents list is primitive
18966 -- for a tagged full type then mark it as a dispatching operation,
18967 -- check whether it overrides an inherited subprogram, and check
18968 -- restrictions on its controlling formals. Note that a protected
18969 -- operation is never dispatching: only its wrapper operation
18970 -- (which has convention Ada) is.
18972 if Is_Tagged_Type (Full_T)
18973 and then Is_Primitive (Priv_Dep)
18974 and then Convention (Priv_Dep) /= Convention_Protected
18976 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
18977 Set_Is_Dispatching_Operation (Priv_Dep);
18978 Check_Controlling_Formals (Full_T, Priv_Dep);
18981 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18983 -- Can happen during processing of a body before the completion
18984 -- of a TA type. Ignore, because spec is also on dependent list.
18988 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18989 -- corresponding subtype of the full view.
18991 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18992 Set_Subtype_Indication
18993 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
18994 Set_Etype (Priv_Dep, Full_T);
18995 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18996 Set_Analyzed (Parent (Priv_Dep), False);
18998 -- Reanalyze the declaration, suppressing the call to
18999 -- Enter_Name to avoid duplicate names.
19001 Analyze_Subtype_Declaration
19002 (N => Parent (Priv_Dep),
19005 -- Dependent is a subtype
19008 -- We build a new subtype indication using the full view of the
19009 -- incomplete parent. The discriminant constraints have been
19010 -- elaborated already at the point of the subtype declaration.
19012 New_Subt := Create_Itype (E_Void, N);
19014 if Has_Discriminants (Full_T) then
19015 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
19017 Disc_Constraint := No_Elist;
19020 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
19021 Set_Full_View (Priv_Dep, New_Subt);
19024 Next_Elmt (Inc_Elmt);
19026 end Process_Incomplete_Dependents;
19028 --------------------------------
19029 -- Process_Range_Expr_In_Decl --
19030 --------------------------------
19032 procedure Process_Range_Expr_In_Decl
19035 Subtyp : Entity_Id := Empty;
19036 Check_List : List_Id := Empty_List;
19037 R_Check_Off : Boolean := False;
19038 In_Iter_Schm : Boolean := False)
19041 R_Checks : Check_Result;
19042 Insert_Node : Node_Id;
19043 Def_Id : Entity_Id;
19046 Analyze_And_Resolve (R, Base_Type (T));
19048 if Nkind (R) = N_Range then
19050 -- In SPARK, all ranges should be static, with the exception of the
19051 -- discrete type definition of a loop parameter specification.
19053 if not In_Iter_Schm
19054 and then not Is_OK_Static_Range (R)
19056 Check_SPARK_Restriction ("range should be static", R);
19059 Lo := Low_Bound (R);
19060 Hi := High_Bound (R);
19062 -- We need to ensure validity of the bounds here, because if we
19063 -- go ahead and do the expansion, then the expanded code will get
19064 -- analyzed with range checks suppressed and we miss the check.
19065 -- Validity checks on the range of a quantified expression are
19066 -- delayed until the construct is transformed into a loop.
19068 if Nkind (Parent (R)) /= N_Loop_Parameter_Specification
19069 or else Nkind (Parent (Parent (R))) /= N_Quantified_Expression
19071 Validity_Check_Range (R);
19074 -- If there were errors in the declaration, try and patch up some
19075 -- common mistakes in the bounds. The cases handled are literals
19076 -- which are Integer where the expected type is Real and vice versa.
19077 -- These corrections allow the compilation process to proceed further
19078 -- along since some basic assumptions of the format of the bounds
19081 if Etype (R) = Any_Type then
19082 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
19084 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
19086 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
19088 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
19090 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
19092 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
19094 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
19096 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
19103 -- If the bounds of the range have been mistakenly given as string
19104 -- literals (perhaps in place of character literals), then an error
19105 -- has already been reported, but we rewrite the string literal as a
19106 -- bound of the range's type to avoid blowups in later processing
19107 -- that looks at static values.
19109 if Nkind (Lo) = N_String_Literal then
19111 Make_Attribute_Reference (Sloc (Lo),
19112 Attribute_Name => Name_First,
19113 Prefix => New_Occurrence_Of (T, Sloc (Lo))));
19114 Analyze_And_Resolve (Lo);
19117 if Nkind (Hi) = N_String_Literal then
19119 Make_Attribute_Reference (Sloc (Hi),
19120 Attribute_Name => Name_First,
19121 Prefix => New_Occurrence_Of (T, Sloc (Hi))));
19122 Analyze_And_Resolve (Hi);
19125 -- If bounds aren't scalar at this point then exit, avoiding
19126 -- problems with further processing of the range in this procedure.
19128 if not Is_Scalar_Type (Etype (Lo)) then
19132 -- Resolve (actually Sem_Eval) has checked that the bounds are in
19133 -- then range of the base type. Here we check whether the bounds
19134 -- are in the range of the subtype itself. Note that if the bounds
19135 -- represent the null range the Constraint_Error exception should
19138 -- ??? The following code should be cleaned up as follows
19140 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
19141 -- is done in the call to Range_Check (R, T); below
19143 -- 2. The use of R_Check_Off should be investigated and possibly
19144 -- removed, this would clean up things a bit.
19146 if Is_Null_Range (Lo, Hi) then
19150 -- Capture values of bounds and generate temporaries for them
19151 -- if needed, before applying checks, since checks may cause
19152 -- duplication of the expression without forcing evaluation.
19154 -- The forced evaluation removes side effects from expressions,
19155 -- which should occur also in GNATprove mode. Otherwise, we end up
19156 -- with unexpected insertions of actions at places where this is
19157 -- not supposed to occur, e.g. on default parameters of a call.
19159 if Expander_Active or GNATprove_Mode then
19161 -- If no subtype name, then just call Force_Evaluation to
19162 -- create declarations as needed to deal with side effects.
19163 -- Also ignore calls from within a record type, where we
19164 -- have possible scoping issues.
19166 if No (Subtyp) or else Is_Record_Type (Current_Scope) then
19167 Force_Evaluation (Lo);
19168 Force_Evaluation (Hi);
19170 -- If a subtype is given, then we capture the bounds if they
19171 -- are not known at compile time, using constant identifiers
19172 -- xxx_FIRST and xxx_LAST where xxx is the name of the subtype.
19174 -- Note: we do this transformation even if expansion is not
19175 -- active, and in particular we do it in GNATprove_Mode since
19176 -- the transformation is in general required to ensure that the
19177 -- resulting tree has proper Ada semantics.
19179 -- Historical note: We used to just do Force_Evaluation calls
19180 -- in all cases, but it is better to capture the bounds with
19181 -- proper non-serialized names, since these will be accessed
19182 -- from other units, and hence may be public, and also we can
19183 -- then expand 'First and 'Last references to be references to
19184 -- these special names.
19187 if not Compile_Time_Known_Value (Lo)
19189 -- No need to capture bounds if they already are
19190 -- references to constants.
19192 and then not (Is_Entity_Name (Lo)
19193 and then Is_Constant_Object (Entity (Lo)))
19196 Loc : constant Source_Ptr := Sloc (Lo);
19197 Lov : constant Entity_Id :=
19198 Make_Defining_Identifier (Loc,
19200 New_External_Name (Chars (Subtyp), "_FIRST"));
19203 Make_Object_Declaration (Loc,
19204 Defining_Identifier => Lov,
19205 Object_Definition =>
19206 New_Occurrence_Of (Base_Type (T), Loc),
19207 Constant_Present => True,
19208 Expression => Relocate_Node (Lo)));
19209 Rewrite (Lo, New_Occurrence_Of (Lov, Loc));
19213 if not Compile_Time_Known_Value (Hi)
19214 and then not (Is_Entity_Name (Hi)
19215 and then Is_Constant_Object (Entity (Hi)))
19218 Loc : constant Source_Ptr := Sloc (Hi);
19219 Hiv : constant Entity_Id :=
19220 Make_Defining_Identifier (Loc,
19222 New_External_Name (Chars (Subtyp), "_LAST"));
19225 Make_Object_Declaration (Loc,
19226 Defining_Identifier => Hiv,
19227 Object_Definition =>
19228 New_Occurrence_Of (Base_Type (T), Loc),
19229 Constant_Present => True,
19230 Expression => Relocate_Node (Hi)));
19231 Rewrite (Hi, New_Occurrence_Of (Hiv, Loc));
19237 -- We use a flag here instead of suppressing checks on the
19238 -- type because the type we check against isn't necessarily
19239 -- the place where we put the check.
19241 if not R_Check_Off then
19242 R_Checks := Get_Range_Checks (R, T);
19244 -- Look up tree to find an appropriate insertion point. We
19245 -- can't just use insert_actions because later processing
19246 -- depends on the insertion node. Prior to Ada 2012 the
19247 -- insertion point could only be a declaration or a loop, but
19248 -- quantified expressions can appear within any context in an
19249 -- expression, and the insertion point can be any statement,
19250 -- pragma, or declaration.
19252 Insert_Node := Parent (R);
19253 while Present (Insert_Node) loop
19255 Nkind (Insert_Node) in N_Declaration
19258 (Insert_Node, N_Component_Declaration,
19259 N_Loop_Parameter_Specification,
19260 N_Function_Specification,
19261 N_Procedure_Specification);
19263 exit when Nkind (Insert_Node) in N_Later_Decl_Item
19264 or else Nkind (Insert_Node) in
19265 N_Statement_Other_Than_Procedure_Call
19266 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
19269 Insert_Node := Parent (Insert_Node);
19272 -- Why would Type_Decl not be present??? Without this test,
19273 -- short regression tests fail.
19275 if Present (Insert_Node) then
19277 -- Case of loop statement. Verify that the range is part
19278 -- of the subtype indication of the iteration scheme.
19280 if Nkind (Insert_Node) = N_Loop_Statement then
19285 Indic := Parent (R);
19286 while Present (Indic)
19287 and then Nkind (Indic) /= N_Subtype_Indication
19289 Indic := Parent (Indic);
19292 if Present (Indic) then
19293 Def_Id := Etype (Subtype_Mark (Indic));
19295 Insert_Range_Checks
19299 Sloc (Insert_Node),
19301 Do_Before => True);
19305 -- Insertion before a declaration. If the declaration
19306 -- includes discriminants, the list of applicable checks
19307 -- is given by the caller.
19309 elsif Nkind (Insert_Node) in N_Declaration then
19310 Def_Id := Defining_Identifier (Insert_Node);
19312 if (Ekind (Def_Id) = E_Record_Type
19313 and then Depends_On_Discriminant (R))
19315 (Ekind (Def_Id) = E_Protected_Type
19316 and then Has_Discriminants (Def_Id))
19318 Append_Range_Checks
19320 Check_List, Def_Id, Sloc (Insert_Node), R);
19323 Insert_Range_Checks
19325 Insert_Node, Def_Id, Sloc (Insert_Node), R);
19329 -- Insertion before a statement. Range appears in the
19330 -- context of a quantified expression. Insertion will
19331 -- take place when expression is expanded.
19340 -- Case of other than an explicit N_Range node
19342 -- The forced evaluation removes side effects from expressions, which
19343 -- should occur also in GNATprove mode. Otherwise, we end up with
19344 -- unexpected insertions of actions at places where this is not
19345 -- supposed to occur, e.g. on default parameters of a call.
19347 elsif Expander_Active or GNATprove_Mode then
19348 Get_Index_Bounds (R, Lo, Hi);
19349 Force_Evaluation (Lo);
19350 Force_Evaluation (Hi);
19352 end Process_Range_Expr_In_Decl;
19354 --------------------------------------
19355 -- Process_Real_Range_Specification --
19356 --------------------------------------
19358 procedure Process_Real_Range_Specification (Def : Node_Id) is
19359 Spec : constant Node_Id := Real_Range_Specification (Def);
19362 Err : Boolean := False;
19364 procedure Analyze_Bound (N : Node_Id);
19365 -- Analyze and check one bound
19367 -------------------
19368 -- Analyze_Bound --
19369 -------------------
19371 procedure Analyze_Bound (N : Node_Id) is
19373 Analyze_And_Resolve (N, Any_Real);
19375 if not Is_OK_Static_Expression (N) then
19376 Flag_Non_Static_Expr
19377 ("bound in real type definition is not static!", N);
19382 -- Start of processing for Process_Real_Range_Specification
19385 if Present (Spec) then
19386 Lo := Low_Bound (Spec);
19387 Hi := High_Bound (Spec);
19388 Analyze_Bound (Lo);
19389 Analyze_Bound (Hi);
19391 -- If error, clear away junk range specification
19394 Set_Real_Range_Specification (Def, Empty);
19397 end Process_Real_Range_Specification;
19399 ---------------------
19400 -- Process_Subtype --
19401 ---------------------
19403 function Process_Subtype
19405 Related_Nod : Node_Id;
19406 Related_Id : Entity_Id := Empty;
19407 Suffix : Character := ' ') return Entity_Id
19410 Def_Id : Entity_Id;
19411 Error_Node : Node_Id;
19412 Full_View_Id : Entity_Id;
19413 Subtype_Mark_Id : Entity_Id;
19415 May_Have_Null_Exclusion : Boolean;
19417 procedure Check_Incomplete (T : Entity_Id);
19418 -- Called to verify that an incomplete type is not used prematurely
19420 ----------------------
19421 -- Check_Incomplete --
19422 ----------------------
19424 procedure Check_Incomplete (T : Entity_Id) is
19426 -- Ada 2005 (AI-412): Incomplete subtypes are legal
19428 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
19430 not (Ada_Version >= Ada_2005
19432 (Nkind (Parent (T)) = N_Subtype_Declaration
19434 (Nkind (Parent (T)) = N_Subtype_Indication
19435 and then Nkind (Parent (Parent (T))) =
19436 N_Subtype_Declaration)))
19438 Error_Msg_N ("invalid use of type before its full declaration", T);
19440 end Check_Incomplete;
19442 -- Start of processing for Process_Subtype
19445 -- Case of no constraints present
19447 if Nkind (S) /= N_Subtype_Indication then
19449 Check_Incomplete (S);
19452 -- Ada 2005 (AI-231): Static check
19454 if Ada_Version >= Ada_2005
19455 and then Present (P)
19456 and then Null_Exclusion_Present (P)
19457 and then Nkind (P) /= N_Access_To_Object_Definition
19458 and then not Is_Access_Type (Entity (S))
19460 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
19463 -- The following is ugly, can't we have a range or even a flag???
19465 May_Have_Null_Exclusion :=
19466 Nkind_In (P, N_Access_Definition,
19467 N_Access_Function_Definition,
19468 N_Access_Procedure_Definition,
19469 N_Access_To_Object_Definition,
19471 N_Component_Definition)
19473 Nkind_In (P, N_Derived_Type_Definition,
19474 N_Discriminant_Specification,
19475 N_Formal_Object_Declaration,
19476 N_Object_Declaration,
19477 N_Object_Renaming_Declaration,
19478 N_Parameter_Specification,
19479 N_Subtype_Declaration);
19481 -- Create an Itype that is a duplicate of Entity (S) but with the
19482 -- null-exclusion attribute.
19484 if May_Have_Null_Exclusion
19485 and then Is_Access_Type (Entity (S))
19486 and then Null_Exclusion_Present (P)
19488 -- No need to check the case of an access to object definition.
19489 -- It is correct to define double not-null pointers.
19492 -- type Not_Null_Int_Ptr is not null access Integer;
19493 -- type Acc is not null access Not_Null_Int_Ptr;
19495 and then Nkind (P) /= N_Access_To_Object_Definition
19497 if Can_Never_Be_Null (Entity (S)) then
19498 case Nkind (Related_Nod) is
19499 when N_Full_Type_Declaration =>
19500 if Nkind (Type_Definition (Related_Nod))
19501 in N_Array_Type_Definition
19505 (Component_Definition
19506 (Type_Definition (Related_Nod)));
19509 Subtype_Indication (Type_Definition (Related_Nod));
19512 when N_Subtype_Declaration =>
19513 Error_Node := Subtype_Indication (Related_Nod);
19515 when N_Object_Declaration =>
19516 Error_Node := Object_Definition (Related_Nod);
19518 when N_Component_Declaration =>
19520 Subtype_Indication (Component_Definition (Related_Nod));
19522 when N_Allocator =>
19523 Error_Node := Expression (Related_Nod);
19526 pragma Assert (False);
19527 Error_Node := Related_Nod;
19531 ("`NOT NULL` not allowed (& already excludes null)",
19537 Create_Null_Excluding_Itype
19539 Related_Nod => P));
19540 Set_Entity (S, Etype (S));
19545 -- Case of constraint present, so that we have an N_Subtype_Indication
19546 -- node (this node is created only if constraints are present).
19549 Find_Type (Subtype_Mark (S));
19551 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
19553 (Nkind (Parent (S)) = N_Subtype_Declaration
19554 and then Is_Itype (Defining_Identifier (Parent (S))))
19556 Check_Incomplete (Subtype_Mark (S));
19560 Subtype_Mark_Id := Entity (Subtype_Mark (S));
19562 -- Explicit subtype declaration case
19564 if Nkind (P) = N_Subtype_Declaration then
19565 Def_Id := Defining_Identifier (P);
19567 -- Explicit derived type definition case
19569 elsif Nkind (P) = N_Derived_Type_Definition then
19570 Def_Id := Defining_Identifier (Parent (P));
19572 -- Implicit case, the Def_Id must be created as an implicit type.
19573 -- The one exception arises in the case of concurrent types, array
19574 -- and access types, where other subsidiary implicit types may be
19575 -- created and must appear before the main implicit type. In these
19576 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
19577 -- has not yet been called to create Def_Id.
19580 if Is_Array_Type (Subtype_Mark_Id)
19581 or else Is_Concurrent_Type (Subtype_Mark_Id)
19582 or else Is_Access_Type (Subtype_Mark_Id)
19586 -- For the other cases, we create a new unattached Itype,
19587 -- and set the indication to ensure it gets attached later.
19591 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19595 -- If the kind of constraint is invalid for this kind of type,
19596 -- then give an error, and then pretend no constraint was given.
19598 if not Is_Valid_Constraint_Kind
19599 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
19602 ("incorrect constraint for this kind of type", Constraint (S));
19604 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
19606 -- Set Ekind of orphan itype, to prevent cascaded errors
19608 if Present (Def_Id) then
19609 Set_Ekind (Def_Id, Ekind (Any_Type));
19612 -- Make recursive call, having got rid of the bogus constraint
19614 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
19617 -- Remaining processing depends on type. Select on Base_Type kind to
19618 -- ensure getting to the concrete type kind in the case of a private
19619 -- subtype (needed when only doing semantic analysis).
19621 case Ekind (Base_Type (Subtype_Mark_Id)) is
19622 when Access_Kind =>
19624 -- If this is a constraint on a class-wide type, discard it.
19625 -- There is currently no way to express a partial discriminant
19626 -- constraint on a type with unknown discriminants. This is
19627 -- a pathology that the ACATS wisely decides not to test.
19629 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
19630 if Comes_From_Source (S) then
19632 ("constraint on class-wide type ignored??",
19636 if Nkind (P) = N_Subtype_Declaration then
19637 Set_Subtype_Indication (P,
19638 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
19641 return Subtype_Mark_Id;
19644 Constrain_Access (Def_Id, S, Related_Nod);
19647 and then Is_Itype (Designated_Type (Def_Id))
19648 and then Nkind (Related_Nod) = N_Subtype_Declaration
19649 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
19651 Build_Itype_Reference
19652 (Designated_Type (Def_Id), Related_Nod);
19656 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
19658 when Decimal_Fixed_Point_Kind =>
19659 Constrain_Decimal (Def_Id, S);
19661 when Enumeration_Kind =>
19662 Constrain_Enumeration (Def_Id, S);
19664 when Ordinary_Fixed_Point_Kind =>
19665 Constrain_Ordinary_Fixed (Def_Id, S);
19668 Constrain_Float (Def_Id, S);
19670 when Integer_Kind =>
19671 Constrain_Integer (Def_Id, S);
19673 when E_Record_Type |
19676 E_Incomplete_Type =>
19677 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19679 if Ekind (Def_Id) = E_Incomplete_Type then
19680 Set_Private_Dependents (Def_Id, New_Elmt_List);
19683 when Private_Kind =>
19684 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19685 Set_Private_Dependents (Def_Id, New_Elmt_List);
19687 -- In case of an invalid constraint prevent further processing
19688 -- since the type constructed is missing expected fields.
19690 if Etype (Def_Id) = Any_Type then
19694 -- If the full view is that of a task with discriminants,
19695 -- we must constrain both the concurrent type and its
19696 -- corresponding record type. Otherwise we will just propagate
19697 -- the constraint to the full view, if available.
19699 if Present (Full_View (Subtype_Mark_Id))
19700 and then Has_Discriminants (Subtype_Mark_Id)
19701 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
19704 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19706 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
19707 Constrain_Concurrent (Full_View_Id, S,
19708 Related_Nod, Related_Id, Suffix);
19709 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
19710 Set_Full_View (Def_Id, Full_View_Id);
19712 -- Introduce an explicit reference to the private subtype,
19713 -- to prevent scope anomalies in gigi if first use appears
19714 -- in a nested context, e.g. a later function body.
19715 -- Should this be generated in other contexts than a full
19716 -- type declaration?
19718 if Is_Itype (Def_Id)
19720 Nkind (Parent (P)) = N_Full_Type_Declaration
19722 Build_Itype_Reference (Def_Id, Parent (P));
19726 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
19729 when Concurrent_Kind =>
19730 Constrain_Concurrent (Def_Id, S,
19731 Related_Nod, Related_Id, Suffix);
19734 Error_Msg_N ("invalid subtype mark in subtype indication", S);
19737 -- Size and Convention are always inherited from the base type
19739 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
19740 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
19744 end Process_Subtype;
19746 ---------------------------------------
19747 -- Check_Anonymous_Access_Components --
19748 ---------------------------------------
19750 procedure Check_Anonymous_Access_Components
19751 (Typ_Decl : Node_Id;
19754 Comp_List : Node_Id)
19756 Loc : constant Source_Ptr := Sloc (Typ_Decl);
19757 Anon_Access : Entity_Id;
19760 Comp_Def : Node_Id;
19762 Type_Def : Node_Id;
19764 procedure Build_Incomplete_Type_Declaration;
19765 -- If the record type contains components that include an access to the
19766 -- current record, then create an incomplete type declaration for the
19767 -- record, to be used as the designated type of the anonymous access.
19768 -- This is done only once, and only if there is no previous partial
19769 -- view of the type.
19771 function Designates_T (Subt : Node_Id) return Boolean;
19772 -- Check whether a node designates the enclosing record type, or 'Class
19775 function Mentions_T (Acc_Def : Node_Id) return Boolean;
19776 -- Check whether an access definition includes a reference to
19777 -- the enclosing record type. The reference can be a subtype mark
19778 -- in the access definition itself, a 'Class attribute reference, or
19779 -- recursively a reference appearing in a parameter specification
19780 -- or result definition of an access_to_subprogram definition.
19782 --------------------------------------
19783 -- Build_Incomplete_Type_Declaration --
19784 --------------------------------------
19786 procedure Build_Incomplete_Type_Declaration is
19791 -- Is_Tagged indicates whether the type is tagged. It is tagged if
19792 -- it's "is new ... with record" or else "is tagged record ...".
19794 Is_Tagged : constant Boolean :=
19795 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
19798 (Record_Extension_Part (Type_Definition (Typ_Decl))))
19800 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
19801 and then Tagged_Present (Type_Definition (Typ_Decl)));
19804 -- If there is a previous partial view, no need to create a new one
19805 -- If the partial view, given by Prev, is incomplete, If Prev is
19806 -- a private declaration, full declaration is flagged accordingly.
19808 if Prev /= Typ then
19810 Make_Class_Wide_Type (Prev);
19811 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
19812 Set_Etype (Class_Wide_Type (Typ), Typ);
19817 elsif Has_Private_Declaration (Typ) then
19819 -- If we refer to T'Class inside T, and T is the completion of a
19820 -- private type, then we need to make sure the class-wide type
19824 Make_Class_Wide_Type (Typ);
19829 -- If there was a previous anonymous access type, the incomplete
19830 -- type declaration will have been created already.
19832 elsif Present (Current_Entity (Typ))
19833 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
19834 and then Full_View (Current_Entity (Typ)) = Typ
19837 and then Comes_From_Source (Current_Entity (Typ))
19838 and then not Is_Tagged_Type (Current_Entity (Typ))
19840 Make_Class_Wide_Type (Typ);
19842 ("incomplete view of tagged type should be declared tagged??",
19843 Parent (Current_Entity (Typ)));
19848 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
19849 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
19851 -- Type has already been inserted into the current scope. Remove
19852 -- it, and add incomplete declaration for type, so that subsequent
19853 -- anonymous access types can use it. The entity is unchained from
19854 -- the homonym list and from immediate visibility. After analysis,
19855 -- the entity in the incomplete declaration becomes immediately
19856 -- visible in the record declaration that follows.
19858 H := Current_Entity (Typ);
19861 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
19864 and then Homonym (H) /= Typ
19866 H := Homonym (Typ);
19869 Set_Homonym (H, Homonym (Typ));
19872 Insert_Before (Typ_Decl, Decl);
19874 Set_Full_View (Inc_T, Typ);
19878 -- Create a common class-wide type for both views, and set the
19879 -- Etype of the class-wide type to the full view.
19881 Make_Class_Wide_Type (Inc_T);
19882 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
19883 Set_Etype (Class_Wide_Type (Typ), Typ);
19886 end Build_Incomplete_Type_Declaration;
19892 function Designates_T (Subt : Node_Id) return Boolean is
19893 Type_Id : constant Name_Id := Chars (Typ);
19895 function Names_T (Nam : Node_Id) return Boolean;
19896 -- The record type has not been introduced in the current scope
19897 -- yet, so we must examine the name of the type itself, either
19898 -- an identifier T, or an expanded name of the form P.T, where
19899 -- P denotes the current scope.
19905 function Names_T (Nam : Node_Id) return Boolean is
19907 if Nkind (Nam) = N_Identifier then
19908 return Chars (Nam) = Type_Id;
19910 elsif Nkind (Nam) = N_Selected_Component then
19911 if Chars (Selector_Name (Nam)) = Type_Id then
19912 if Nkind (Prefix (Nam)) = N_Identifier then
19913 return Chars (Prefix (Nam)) = Chars (Current_Scope);
19915 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
19916 return Chars (Selector_Name (Prefix (Nam))) =
19917 Chars (Current_Scope);
19931 -- Start of processing for Designates_T
19934 if Nkind (Subt) = N_Identifier then
19935 return Chars (Subt) = Type_Id;
19937 -- Reference can be through an expanded name which has not been
19938 -- analyzed yet, and which designates enclosing scopes.
19940 elsif Nkind (Subt) = N_Selected_Component then
19941 if Names_T (Subt) then
19944 -- Otherwise it must denote an entity that is already visible.
19945 -- The access definition may name a subtype of the enclosing
19946 -- type, if there is a previous incomplete declaration for it.
19949 Find_Selected_Component (Subt);
19951 Is_Entity_Name (Subt)
19952 and then Scope (Entity (Subt)) = Current_Scope
19954 (Chars (Base_Type (Entity (Subt))) = Type_Id
19956 (Is_Class_Wide_Type (Entity (Subt))
19958 Chars (Etype (Base_Type (Entity (Subt)))) =
19962 -- A reference to the current type may appear as the prefix of
19963 -- a 'Class attribute.
19965 elsif Nkind (Subt) = N_Attribute_Reference
19966 and then Attribute_Name (Subt) = Name_Class
19968 return Names_T (Prefix (Subt));
19979 function Mentions_T (Acc_Def : Node_Id) return Boolean is
19980 Param_Spec : Node_Id;
19982 Acc_Subprg : constant Node_Id :=
19983 Access_To_Subprogram_Definition (Acc_Def);
19986 if No (Acc_Subprg) then
19987 return Designates_T (Subtype_Mark (Acc_Def));
19990 -- Component is an access_to_subprogram: examine its formals,
19991 -- and result definition in the case of an access_to_function.
19993 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
19994 while Present (Param_Spec) loop
19995 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
19996 and then Mentions_T (Parameter_Type (Param_Spec))
20000 elsif Designates_T (Parameter_Type (Param_Spec)) then
20007 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
20008 if Nkind (Result_Definition (Acc_Subprg)) =
20009 N_Access_Definition
20011 return Mentions_T (Result_Definition (Acc_Subprg));
20013 return Designates_T (Result_Definition (Acc_Subprg));
20020 -- Start of processing for Check_Anonymous_Access_Components
20023 if No (Comp_List) then
20027 Comp := First (Component_Items (Comp_List));
20028 while Present (Comp) loop
20029 if Nkind (Comp) = N_Component_Declaration
20031 (Access_Definition (Component_Definition (Comp)))
20033 Mentions_T (Access_Definition (Component_Definition (Comp)))
20035 Comp_Def := Component_Definition (Comp);
20037 Access_To_Subprogram_Definition
20038 (Access_Definition (Comp_Def));
20040 Build_Incomplete_Type_Declaration;
20041 Anon_Access := Make_Temporary (Loc, 'S');
20043 -- Create a declaration for the anonymous access type: either
20044 -- an access_to_object or an access_to_subprogram.
20046 if Present (Acc_Def) then
20047 if Nkind (Acc_Def) = N_Access_Function_Definition then
20049 Make_Access_Function_Definition (Loc,
20050 Parameter_Specifications =>
20051 Parameter_Specifications (Acc_Def),
20052 Result_Definition => Result_Definition (Acc_Def));
20055 Make_Access_Procedure_Definition (Loc,
20056 Parameter_Specifications =>
20057 Parameter_Specifications (Acc_Def));
20062 Make_Access_To_Object_Definition (Loc,
20063 Subtype_Indication =>
20066 (Access_Definition (Comp_Def))));
20068 Set_Constant_Present
20069 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
20071 (Type_Def, All_Present (Access_Definition (Comp_Def)));
20074 Set_Null_Exclusion_Present
20076 Null_Exclusion_Present (Access_Definition (Comp_Def)));
20079 Make_Full_Type_Declaration (Loc,
20080 Defining_Identifier => Anon_Access,
20081 Type_Definition => Type_Def);
20083 Insert_Before (Typ_Decl, Decl);
20086 -- If an access to subprogram, create the extra formals
20088 if Present (Acc_Def) then
20089 Create_Extra_Formals (Designated_Type (Anon_Access));
20091 -- If an access to object, preserve entity of designated type,
20092 -- for ASIS use, before rewriting the component definition.
20099 Desig := Entity (Subtype_Indication (Type_Def));
20101 -- If the access definition is to the current record,
20102 -- the visible entity at this point is an incomplete
20103 -- type. Retrieve the full view to simplify ASIS queries
20105 if Ekind (Desig) = E_Incomplete_Type then
20106 Desig := Full_View (Desig);
20110 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
20115 Make_Component_Definition (Loc,
20116 Subtype_Indication =>
20117 New_Occurrence_Of (Anon_Access, Loc)));
20119 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
20120 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
20122 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
20125 Set_Is_Local_Anonymous_Access (Anon_Access);
20131 if Present (Variant_Part (Comp_List)) then
20135 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
20136 while Present (V) loop
20137 Check_Anonymous_Access_Components
20138 (Typ_Decl, Typ, Prev, Component_List (V));
20139 Next_Non_Pragma (V);
20143 end Check_Anonymous_Access_Components;
20145 ----------------------------------
20146 -- Preanalyze_Assert_Expression --
20147 ----------------------------------
20149 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
20151 In_Assertion_Expr := In_Assertion_Expr + 1;
20152 Preanalyze_Spec_Expression (N, T);
20153 In_Assertion_Expr := In_Assertion_Expr - 1;
20154 end Preanalyze_Assert_Expression;
20156 --------------------------------
20157 -- Preanalyze_Spec_Expression --
20158 --------------------------------
20160 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
20161 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
20163 In_Spec_Expression := True;
20164 Preanalyze_And_Resolve (N, T);
20165 In_Spec_Expression := Save_In_Spec_Expression;
20166 end Preanalyze_Spec_Expression;
20168 -----------------------------
20169 -- Record_Type_Declaration --
20170 -----------------------------
20172 procedure Record_Type_Declaration
20177 Def : constant Node_Id := Type_Definition (N);
20178 Is_Tagged : Boolean;
20179 Tag_Comp : Entity_Id;
20182 -- These flags must be initialized before calling Process_Discriminants
20183 -- because this routine makes use of them.
20185 Set_Ekind (T, E_Record_Type);
20187 Init_Size_Align (T);
20188 Set_Interfaces (T, No_Elist);
20189 Set_Stored_Constraint (T, No_Elist);
20190 Set_Default_SSO (T);
20194 if Ada_Version < Ada_2005
20195 or else not Interface_Present (Def)
20197 if Limited_Present (Def) then
20198 Check_SPARK_Restriction ("limited is not allowed", N);
20201 if Abstract_Present (Def) then
20202 Check_SPARK_Restriction ("abstract is not allowed", N);
20205 -- The flag Is_Tagged_Type might have already been set by
20206 -- Find_Type_Name if it detected an error for declaration T. This
20207 -- arises in the case of private tagged types where the full view
20208 -- omits the word tagged.
20211 Tagged_Present (Def)
20212 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20214 Set_Is_Tagged_Type (T, Is_Tagged);
20215 Set_Is_Limited_Record (T, Limited_Present (Def));
20217 -- Type is abstract if full declaration carries keyword, or if
20218 -- previous partial view did.
20220 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20221 or else Abstract_Present (Def));
20224 Check_SPARK_Restriction ("interface is not allowed", N);
20227 Analyze_Interface_Declaration (T, Def);
20229 if Present (Discriminant_Specifications (N)) then
20231 ("interface types cannot have discriminants",
20232 Defining_Identifier
20233 (First (Discriminant_Specifications (N))));
20237 -- First pass: if there are self-referential access components,
20238 -- create the required anonymous access type declarations, and if
20239 -- need be an incomplete type declaration for T itself.
20241 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20243 if Ada_Version >= Ada_2005
20244 and then Present (Interface_List (Def))
20246 Check_Interfaces (N, Def);
20249 Ifaces_List : Elist_Id;
20252 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20253 -- already in the parents.
20257 Ifaces_List => Ifaces_List,
20258 Exclude_Parents => True);
20260 Set_Interfaces (T, Ifaces_List);
20264 -- Records constitute a scope for the component declarations within.
20265 -- The scope is created prior to the processing of these declarations.
20266 -- Discriminants are processed first, so that they are visible when
20267 -- processing the other components. The Ekind of the record type itself
20268 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20270 -- Enter record scope
20274 -- If an incomplete or private type declaration was already given for
20275 -- the type, then this scope already exists, and the discriminants have
20276 -- been declared within. We must verify that the full declaration
20277 -- matches the incomplete one.
20279 Check_Or_Process_Discriminants (N, T, Prev);
20281 Set_Is_Constrained (T, not Has_Discriminants (T));
20282 Set_Has_Delayed_Freeze (T, True);
20284 -- For tagged types add a manually analyzed component corresponding
20285 -- to the component _tag, the corresponding piece of tree will be
20286 -- expanded as part of the freezing actions if it is not a CPP_Class.
20290 -- Do not add the tag unless we are in expansion mode
20292 if Expander_Active then
20293 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20294 Enter_Name (Tag_Comp);
20296 Set_Ekind (Tag_Comp, E_Component);
20297 Set_Is_Tag (Tag_Comp);
20298 Set_Is_Aliased (Tag_Comp);
20299 Set_Etype (Tag_Comp, RTE (RE_Tag));
20300 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20301 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20302 Init_Component_Location (Tag_Comp);
20304 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20305 -- implemented interfaces.
20307 if Has_Interfaces (T) then
20308 Add_Interface_Tag_Components (N, T);
20312 Make_Class_Wide_Type (T);
20313 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20316 -- We must suppress range checks when processing record components in
20317 -- the presence of discriminants, since we don't want spurious checks to
20318 -- be generated during their analysis, but Suppress_Range_Checks flags
20319 -- must be reset the after processing the record definition.
20321 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20322 -- couldn't we just use the normal range check suppression method here.
20323 -- That would seem cleaner ???
20325 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20326 Set_Kill_Range_Checks (T, True);
20327 Record_Type_Definition (Def, Prev);
20328 Set_Kill_Range_Checks (T, False);
20330 Record_Type_Definition (Def, Prev);
20333 -- Exit from record scope
20337 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20338 -- the implemented interfaces and associate them an aliased entity.
20341 and then not Is_Empty_List (Interface_List (Def))
20343 Derive_Progenitor_Subprograms (T, T);
20346 Check_Function_Writable_Actuals (N);
20347 end Record_Type_Declaration;
20349 ----------------------------
20350 -- Record_Type_Definition --
20351 ----------------------------
20353 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20354 Component : Entity_Id;
20355 Ctrl_Components : Boolean := False;
20356 Final_Storage_Only : Boolean;
20360 if Ekind (Prev_T) = E_Incomplete_Type then
20361 T := Full_View (Prev_T);
20366 -- In SPARK, tagged types and type extensions may only be declared in
20367 -- the specification of library unit packages.
20369 if Present (Def) and then Is_Tagged_Type (T) then
20375 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
20376 Typ := Parent (Def);
20379 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
20380 Typ := Parent (Parent (Def));
20383 Ctxt := Parent (Typ);
20385 if Nkind (Ctxt) = N_Package_Body
20386 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
20388 Check_SPARK_Restriction
20389 ("type should be defined in package specification", Typ);
20391 elsif Nkind (Ctxt) /= N_Package_Specification
20392 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
20394 Check_SPARK_Restriction
20395 ("type should be defined in library unit package", Typ);
20400 Final_Storage_Only := not Is_Controlled (T);
20402 -- Ada 2005: Check whether an explicit Limited is present in a derived
20403 -- type declaration.
20405 if Nkind (Parent (Def)) = N_Derived_Type_Definition
20406 and then Limited_Present (Parent (Def))
20408 Set_Is_Limited_Record (T);
20411 -- If the component list of a record type is defined by the reserved
20412 -- word null and there is no discriminant part, then the record type has
20413 -- no components and all records of the type are null records (RM 3.7)
20414 -- This procedure is also called to process the extension part of a
20415 -- record extension, in which case the current scope may have inherited
20419 or else No (Component_List (Def))
20420 or else Null_Present (Component_List (Def))
20422 if not Is_Tagged_Type (T) then
20423 Check_SPARK_Restriction ("untagged record cannot be null", Def);
20427 Analyze_Declarations (Component_Items (Component_List (Def)));
20429 if Present (Variant_Part (Component_List (Def))) then
20430 Check_SPARK_Restriction ("variant part is not allowed", Def);
20431 Analyze (Variant_Part (Component_List (Def)));
20435 -- After completing the semantic analysis of the record definition,
20436 -- record components, both new and inherited, are accessible. Set their
20437 -- kind accordingly. Exclude malformed itypes from illegal declarations,
20438 -- whose Ekind may be void.
20440 Component := First_Entity (Current_Scope);
20441 while Present (Component) loop
20442 if Ekind (Component) = E_Void
20443 and then not Is_Itype (Component)
20445 Set_Ekind (Component, E_Component);
20446 Init_Component_Location (Component);
20449 if Has_Task (Etype (Component)) then
20453 if Has_Protected (Etype (Component)) then
20454 Set_Has_Protected (T);
20457 if Ekind (Component) /= E_Component then
20460 -- Do not set Has_Controlled_Component on a class-wide equivalent
20461 -- type. See Make_CW_Equivalent_Type.
20463 elsif not Is_Class_Wide_Equivalent_Type (T)
20464 and then (Has_Controlled_Component (Etype (Component))
20465 or else (Chars (Component) /= Name_uParent
20466 and then Is_Controlled (Etype (Component))))
20468 Set_Has_Controlled_Component (T, True);
20469 Final_Storage_Only :=
20471 and then Finalize_Storage_Only (Etype (Component));
20472 Ctrl_Components := True;
20475 Next_Entity (Component);
20478 -- A Type is Finalize_Storage_Only only if all its controlled components
20481 if Ctrl_Components then
20482 Set_Finalize_Storage_Only (T, Final_Storage_Only);
20485 -- Place reference to end record on the proper entity, which may
20486 -- be a partial view.
20488 if Present (Def) then
20489 Process_End_Label (Def, 'e', Prev_T);
20491 end Record_Type_Definition;
20493 ------------------------
20494 -- Replace_Components --
20495 ------------------------
20497 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
20498 function Process (N : Node_Id) return Traverse_Result;
20504 function Process (N : Node_Id) return Traverse_Result is
20508 if Nkind (N) = N_Discriminant_Specification then
20509 Comp := First_Discriminant (Typ);
20510 while Present (Comp) loop
20511 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20512 Set_Defining_Identifier (N, Comp);
20516 Next_Discriminant (Comp);
20519 elsif Nkind (N) = N_Component_Declaration then
20520 Comp := First_Component (Typ);
20521 while Present (Comp) loop
20522 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20523 Set_Defining_Identifier (N, Comp);
20527 Next_Component (Comp);
20534 procedure Replace is new Traverse_Proc (Process);
20536 -- Start of processing for Replace_Components
20540 end Replace_Components;
20542 -------------------------------
20543 -- Set_Completion_Referenced --
20544 -------------------------------
20546 procedure Set_Completion_Referenced (E : Entity_Id) is
20548 -- If in main unit, mark entity that is a completion as referenced,
20549 -- warnings go on the partial view when needed.
20551 if In_Extended_Main_Source_Unit (E) then
20552 Set_Referenced (E);
20554 end Set_Completion_Referenced;
20556 ---------------------
20557 -- Set_Default_SSO --
20558 ---------------------
20560 procedure Set_Default_SSO (T : Entity_Id) is
20562 case Opt.Default_SSO is
20566 Set_SSO_Set_Low_By_Default (T, True);
20568 Set_SSO_Set_High_By_Default (T, True);
20570 raise Program_Error;
20572 end Set_Default_SSO;
20574 ---------------------
20575 -- Set_Fixed_Range --
20576 ---------------------
20578 -- The range for fixed-point types is complicated by the fact that we
20579 -- do not know the exact end points at the time of the declaration. This
20580 -- is true for three reasons:
20582 -- A size clause may affect the fudging of the end-points.
20583 -- A small clause may affect the values of the end-points.
20584 -- We try to include the end-points if it does not affect the size.
20586 -- This means that the actual end-points must be established at the
20587 -- point when the type is frozen. Meanwhile, we first narrow the range
20588 -- as permitted (so that it will fit if necessary in a small specified
20589 -- size), and then build a range subtree with these narrowed bounds.
20590 -- Set_Fixed_Range constructs the range from real literal values, and
20591 -- sets the range as the Scalar_Range of the given fixed-point type entity.
20593 -- The parent of this range is set to point to the entity so that it is
20594 -- properly hooked into the tree (unlike normal Scalar_Range entries for
20595 -- other scalar types, which are just pointers to the range in the
20596 -- original tree, this would otherwise be an orphan).
20598 -- The tree is left unanalyzed. When the type is frozen, the processing
20599 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
20600 -- analyzed, and uses this as an indication that it should complete
20601 -- work on the range (it will know the final small and size values).
20603 procedure Set_Fixed_Range
20609 S : constant Node_Id :=
20611 Low_Bound => Make_Real_Literal (Loc, Lo),
20612 High_Bound => Make_Real_Literal (Loc, Hi));
20614 Set_Scalar_Range (E, S);
20617 -- Before the freeze point, the bounds of a fixed point are universal
20618 -- and carry the corresponding type.
20620 Set_Etype (Low_Bound (S), Universal_Real);
20621 Set_Etype (High_Bound (S), Universal_Real);
20622 end Set_Fixed_Range;
20624 ----------------------------------
20625 -- Set_Scalar_Range_For_Subtype --
20626 ----------------------------------
20628 procedure Set_Scalar_Range_For_Subtype
20629 (Def_Id : Entity_Id;
20633 Kind : constant Entity_Kind := Ekind (Def_Id);
20636 -- Defend against previous error
20638 if Nkind (R) = N_Error then
20642 Set_Scalar_Range (Def_Id, R);
20644 -- We need to link the range into the tree before resolving it so
20645 -- that types that are referenced, including importantly the subtype
20646 -- itself, are properly frozen (Freeze_Expression requires that the
20647 -- expression be properly linked into the tree). Of course if it is
20648 -- already linked in, then we do not disturb the current link.
20650 if No (Parent (R)) then
20651 Set_Parent (R, Def_Id);
20654 -- Reset the kind of the subtype during analysis of the range, to
20655 -- catch possible premature use in the bounds themselves.
20657 Set_Ekind (Def_Id, E_Void);
20658 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
20659 Set_Ekind (Def_Id, Kind);
20660 end Set_Scalar_Range_For_Subtype;
20662 --------------------------------------------------------
20663 -- Set_Stored_Constraint_From_Discriminant_Constraint --
20664 --------------------------------------------------------
20666 procedure Set_Stored_Constraint_From_Discriminant_Constraint
20670 -- Make sure set if encountered during Expand_To_Stored_Constraint
20672 Set_Stored_Constraint (E, No_Elist);
20674 -- Give it the right value
20676 if Is_Constrained (E) and then Has_Discriminants (E) then
20677 Set_Stored_Constraint (E,
20678 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
20680 end Set_Stored_Constraint_From_Discriminant_Constraint;
20682 -------------------------------------
20683 -- Signed_Integer_Type_Declaration --
20684 -------------------------------------
20686 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
20687 Implicit_Base : Entity_Id;
20688 Base_Typ : Entity_Id;
20691 Errs : Boolean := False;
20695 function Can_Derive_From (E : Entity_Id) return Boolean;
20696 -- Determine whether given bounds allow derivation from specified type
20698 procedure Check_Bound (Expr : Node_Id);
20699 -- Check bound to make sure it is integral and static. If not, post
20700 -- appropriate error message and set Errs flag
20702 ---------------------
20703 -- Can_Derive_From --
20704 ---------------------
20706 -- Note we check both bounds against both end values, to deal with
20707 -- strange types like ones with a range of 0 .. -12341234.
20709 function Can_Derive_From (E : Entity_Id) return Boolean is
20710 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
20711 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
20713 return Lo <= Lo_Val and then Lo_Val <= Hi
20715 Lo <= Hi_Val and then Hi_Val <= Hi;
20716 end Can_Derive_From;
20722 procedure Check_Bound (Expr : Node_Id) is
20724 -- If a range constraint is used as an integer type definition, each
20725 -- bound of the range must be defined by a static expression of some
20726 -- integer type, but the two bounds need not have the same integer
20727 -- type (Negative bounds are allowed.) (RM 3.5.4)
20729 if not Is_Integer_Type (Etype (Expr)) then
20731 ("integer type definition bounds must be of integer type", Expr);
20734 elsif not Is_OK_Static_Expression (Expr) then
20735 Flag_Non_Static_Expr
20736 ("non-static expression used for integer type bound!", Expr);
20739 -- The bounds are folded into literals, and we set their type to be
20740 -- universal, to avoid typing difficulties: we cannot set the type
20741 -- of the literal to the new type, because this would be a forward
20742 -- reference for the back end, and if the original type is user-
20743 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
20746 if Is_Entity_Name (Expr) then
20747 Fold_Uint (Expr, Expr_Value (Expr), True);
20750 Set_Etype (Expr, Universal_Integer);
20754 -- Start of processing for Signed_Integer_Type_Declaration
20757 -- Create an anonymous base type
20760 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
20762 -- Analyze and check the bounds, they can be of any integer type
20764 Lo := Low_Bound (Def);
20765 Hi := High_Bound (Def);
20767 -- Arbitrarily use Integer as the type if either bound had an error
20769 if Hi = Error or else Lo = Error then
20770 Base_Typ := Any_Integer;
20771 Set_Error_Posted (T, True);
20773 -- Here both bounds are OK expressions
20776 Analyze_And_Resolve (Lo, Any_Integer);
20777 Analyze_And_Resolve (Hi, Any_Integer);
20783 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20784 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20787 -- Find type to derive from
20789 Lo_Val := Expr_Value (Lo);
20790 Hi_Val := Expr_Value (Hi);
20792 if Can_Derive_From (Standard_Short_Short_Integer) then
20793 Base_Typ := Base_Type (Standard_Short_Short_Integer);
20795 elsif Can_Derive_From (Standard_Short_Integer) then
20796 Base_Typ := Base_Type (Standard_Short_Integer);
20798 elsif Can_Derive_From (Standard_Integer) then
20799 Base_Typ := Base_Type (Standard_Integer);
20801 elsif Can_Derive_From (Standard_Long_Integer) then
20802 Base_Typ := Base_Type (Standard_Long_Integer);
20804 elsif Can_Derive_From (Standard_Long_Long_Integer) then
20805 Check_Restriction (No_Long_Long_Integers, Def);
20806 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20809 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20810 Error_Msg_N ("integer type definition bounds out of range", Def);
20811 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20812 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20816 -- Complete both implicit base and declared first subtype entities
20818 Set_Etype (Implicit_Base, Base_Typ);
20819 Set_Size_Info (Implicit_Base, (Base_Typ));
20820 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
20821 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
20823 Set_Ekind (T, E_Signed_Integer_Subtype);
20824 Set_Etype (T, Implicit_Base);
20826 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
20828 Set_Size_Info (T, (Implicit_Base));
20829 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
20830 Set_Scalar_Range (T, Def);
20831 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
20832 Set_Is_Constrained (T);
20833 end Signed_Integer_Type_Declaration;