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 effectively volatile. This check is only
3022 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3023 -- rule. Do not flag internally-generated constants that map generic
3024 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3027 and then Is_Effectively_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_Effectively_Volatile (Obj_Id) then
3041 -- The declaration of an effectively volatile object must
3042 -- appear at the 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 effectively
3050 -- volatile (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 effectively 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 effectively volatile
3066 -- A non-effectively volatile object cannot have effectively
3067 -- volatile components (SPARK RM 7.1.3(7)).
3069 if not Is_Effectively_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_Has_Dynamic_Predicate_Aspect
4518 (Id, Has_Dynamic_Predicate_Aspect (T));
4519 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4520 Set_Scalar_Range (Id, Scalar_Range (T));
4521 Set_Is_Character_Type (Id, Is_Character_Type (T));
4522 Set_Is_Constrained (Id, Is_Constrained (T));
4523 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4524 Set_RM_Size (Id, RM_Size (T));
4526 when Ordinary_Fixed_Point_Kind =>
4527 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4528 Set_Scalar_Range (Id, Scalar_Range (T));
4529 Set_Small_Value (Id, Small_Value (T));
4530 Set_Delta_Value (Id, Delta_Value (T));
4531 Set_Is_Constrained (Id, Is_Constrained (T));
4532 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4533 Set_RM_Size (Id, RM_Size (T));
4536 Set_Ekind (Id, E_Floating_Point_Subtype);
4537 Set_Scalar_Range (Id, Scalar_Range (T));
4538 Set_Digits_Value (Id, Digits_Value (T));
4539 Set_Is_Constrained (Id, Is_Constrained (T));
4541 when Signed_Integer_Kind =>
4542 Set_Ekind (Id, E_Signed_Integer_Subtype);
4543 Set_Scalar_Range (Id, Scalar_Range (T));
4544 Set_Is_Constrained (Id, Is_Constrained (T));
4545 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4546 Set_RM_Size (Id, RM_Size (T));
4548 when Modular_Integer_Kind =>
4549 Set_Ekind (Id, E_Modular_Integer_Subtype);
4550 Set_Scalar_Range (Id, Scalar_Range (T));
4551 Set_Is_Constrained (Id, Is_Constrained (T));
4552 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4553 Set_RM_Size (Id, RM_Size (T));
4555 when Class_Wide_Kind =>
4556 Set_Ekind (Id, E_Class_Wide_Subtype);
4557 Set_First_Entity (Id, First_Entity (T));
4558 Set_Last_Entity (Id, Last_Entity (T));
4559 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4560 Set_Cloned_Subtype (Id, T);
4561 Set_Is_Tagged_Type (Id, True);
4562 Set_Has_Unknown_Discriminants
4565 if Ekind (T) = E_Class_Wide_Subtype then
4566 Set_Equivalent_Type (Id, Equivalent_Type (T));
4569 when E_Record_Type | E_Record_Subtype =>
4570 Set_Ekind (Id, E_Record_Subtype);
4572 if Ekind (T) = E_Record_Subtype
4573 and then Present (Cloned_Subtype (T))
4575 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4577 Set_Cloned_Subtype (Id, T);
4580 Set_First_Entity (Id, First_Entity (T));
4581 Set_Last_Entity (Id, Last_Entity (T));
4582 Set_Has_Discriminants (Id, Has_Discriminants (T));
4583 Set_Is_Constrained (Id, Is_Constrained (T));
4584 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4585 Set_Has_Implicit_Dereference
4586 (Id, Has_Implicit_Dereference (T));
4587 Set_Has_Unknown_Discriminants
4588 (Id, Has_Unknown_Discriminants (T));
4590 if Has_Discriminants (T) then
4591 Set_Discriminant_Constraint
4592 (Id, Discriminant_Constraint (T));
4593 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4595 elsif Has_Unknown_Discriminants (Id) then
4596 Set_Discriminant_Constraint (Id, No_Elist);
4599 if Is_Tagged_Type (T) then
4600 Set_Is_Tagged_Type (Id);
4601 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4602 Set_Direct_Primitive_Operations
4603 (Id, Direct_Primitive_Operations (T));
4604 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4606 if Is_Interface (T) then
4607 Set_Is_Interface (Id);
4608 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4612 when Private_Kind =>
4613 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4614 Set_Has_Discriminants (Id, Has_Discriminants (T));
4615 Set_Is_Constrained (Id, Is_Constrained (T));
4616 Set_First_Entity (Id, First_Entity (T));
4617 Set_Last_Entity (Id, Last_Entity (T));
4618 Set_Private_Dependents (Id, New_Elmt_List);
4619 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4620 Set_Has_Implicit_Dereference
4621 (Id, Has_Implicit_Dereference (T));
4622 Set_Has_Unknown_Discriminants
4623 (Id, Has_Unknown_Discriminants (T));
4624 Set_Known_To_Have_Preelab_Init
4625 (Id, Known_To_Have_Preelab_Init (T));
4627 if Is_Tagged_Type (T) then
4628 Set_Is_Tagged_Type (Id);
4629 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4630 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4631 Set_Direct_Primitive_Operations (Id,
4632 Direct_Primitive_Operations (T));
4635 -- In general the attributes of the subtype of a private type
4636 -- are the attributes of the partial view of parent. However,
4637 -- the full view may be a discriminated type, and the subtype
4638 -- must share the discriminant constraint to generate correct
4639 -- calls to initialization procedures.
4641 if Has_Discriminants (T) then
4642 Set_Discriminant_Constraint
4643 (Id, Discriminant_Constraint (T));
4644 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4646 elsif Present (Full_View (T))
4647 and then Has_Discriminants (Full_View (T))
4649 Set_Discriminant_Constraint
4650 (Id, Discriminant_Constraint (Full_View (T)));
4651 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4653 -- This would seem semantically correct, but apparently
4654 -- generates spurious errors about missing components ???
4656 -- Set_Has_Discriminants (Id);
4659 Prepare_Private_Subtype_Completion (Id, N);
4661 -- If this is the subtype of a constrained private type with
4662 -- discriminants that has got a full view and we also have
4663 -- built a completion just above, show that the completion
4664 -- is a clone of the full view to the back-end.
4666 if Has_Discriminants (T)
4667 and then not Has_Unknown_Discriminants (T)
4668 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4669 and then Present (Full_View (T))
4670 and then Present (Full_View (Id))
4672 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4676 Set_Ekind (Id, E_Access_Subtype);
4677 Set_Is_Constrained (Id, Is_Constrained (T));
4678 Set_Is_Access_Constant
4679 (Id, Is_Access_Constant (T));
4680 Set_Directly_Designated_Type
4681 (Id, Designated_Type (T));
4682 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4684 -- A Pure library_item must not contain the declaration of a
4685 -- named access type, except within a subprogram, generic
4686 -- subprogram, task unit, or protected unit, or if it has
4687 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4689 if Comes_From_Source (Id)
4690 and then In_Pure_Unit
4691 and then not In_Subprogram_Task_Protected_Unit
4692 and then not No_Pool_Assigned (Id)
4695 ("named access types not allowed in pure unit", N);
4698 when Concurrent_Kind =>
4699 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4700 Set_Corresponding_Record_Type (Id,
4701 Corresponding_Record_Type (T));
4702 Set_First_Entity (Id, First_Entity (T));
4703 Set_First_Private_Entity (Id, First_Private_Entity (T));
4704 Set_Has_Discriminants (Id, Has_Discriminants (T));
4705 Set_Is_Constrained (Id, Is_Constrained (T));
4706 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4707 Set_Last_Entity (Id, Last_Entity (T));
4709 if Has_Discriminants (T) then
4710 Set_Discriminant_Constraint (Id,
4711 Discriminant_Constraint (T));
4712 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4715 when E_Incomplete_Type =>
4716 if Ada_Version >= Ada_2005 then
4718 -- In Ada 2005 an incomplete type can be explicitly tagged:
4719 -- propagate indication.
4721 Set_Ekind (Id, E_Incomplete_Subtype);
4722 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4723 Set_Private_Dependents (Id, New_Elmt_List);
4725 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
4726 -- incomplete type visible through a limited with clause.
4728 if From_Limited_With (T)
4729 and then Present (Non_Limited_View (T))
4731 Set_From_Limited_With (Id);
4732 Set_Non_Limited_View (Id, Non_Limited_View (T));
4734 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4735 -- to the private dependents of the original incomplete
4736 -- type for future transformation.
4739 Append_Elmt (Id, Private_Dependents (T));
4742 -- If the subtype name denotes an incomplete type an error
4743 -- was already reported by Process_Subtype.
4746 Set_Etype (Id, Any_Type);
4750 raise Program_Error;
4754 if Etype (Id) = Any_Type then
4758 -- Some common processing on all types
4760 Set_Size_Info (Id, T);
4761 Set_First_Rep_Item (Id, First_Rep_Item (T));
4763 -- If the parent type is a generic actual, so is the subtype. This may
4764 -- happen in a nested instance. Why Comes_From_Source test???
4766 if not Comes_From_Source (N) then
4767 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
4772 Set_Is_Immediately_Visible (Id, True);
4773 Set_Depends_On_Private (Id, Has_Private_Component (T));
4774 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4776 if Is_Interface (T) then
4777 Set_Is_Interface (Id);
4780 if Present (Generic_Parent_Type (N))
4782 (Nkind (Parent (Generic_Parent_Type (N))) /=
4783 N_Formal_Type_Declaration
4785 (Formal_Type_Definition (Parent (Generic_Parent_Type (N)))) /=
4786 N_Formal_Private_Type_Definition)
4788 if Is_Tagged_Type (Id) then
4790 -- If this is a generic actual subtype for a synchronized type,
4791 -- the primitive operations are those of the corresponding record
4792 -- for which there is a separate subtype declaration.
4794 if Is_Concurrent_Type (Id) then
4796 elsif Is_Class_Wide_Type (Id) then
4797 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4799 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4802 elsif Scope (Etype (Id)) /= Standard_Standard then
4803 Derive_Subprograms (Generic_Parent_Type (N), Id);
4807 if Is_Private_Type (T) and then Present (Full_View (T)) then
4808 Conditional_Delay (Id, Full_View (T));
4810 -- The subtypes of components or subcomponents of protected types
4811 -- do not need freeze nodes, which would otherwise appear in the
4812 -- wrong scope (before the freeze node for the protected type). The
4813 -- proper subtypes are those of the subcomponents of the corresponding
4816 elsif Ekind (Scope (Id)) /= E_Protected_Type
4817 and then Present (Scope (Scope (Id))) -- error defense
4818 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4820 Conditional_Delay (Id, T);
4823 -- Check that Constraint_Error is raised for a scalar subtype indication
4824 -- when the lower or upper bound of a non-null range lies outside the
4825 -- range of the type mark.
4827 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4828 if Is_Scalar_Type (Etype (Id))
4829 and then Scalar_Range (Id) /=
4830 Scalar_Range (Etype (Subtype_Mark
4831 (Subtype_Indication (N))))
4835 Etype (Subtype_Mark (Subtype_Indication (N))));
4837 -- In the array case, check compatibility for each index
4839 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
4841 -- This really should be a subprogram that finds the indications
4845 Subt_Index : Node_Id := First_Index (Id);
4846 Target_Index : Node_Id :=
4848 (Subtype_Mark (Subtype_Indication (N))));
4849 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4852 while Present (Subt_Index) loop
4853 if ((Nkind (Subt_Index) = N_Identifier
4854 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4855 or else Nkind (Subt_Index) = N_Subtype_Indication)
4857 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4860 Target_Typ : constant Entity_Id :=
4861 Etype (Target_Index);
4865 (Scalar_Range (Etype (Subt_Index)),
4868 Defining_Identifier (N));
4870 -- Reset Has_Dynamic_Range_Check on the subtype to
4871 -- prevent elision of the index check due to a dynamic
4872 -- check generated for a preceding index (needed since
4873 -- Insert_Range_Checks tries to avoid generating
4874 -- redundant checks on a given declaration).
4876 Set_Has_Dynamic_Range_Check (N, False);
4882 Sloc (Defining_Identifier (N)));
4884 -- Record whether this index involved a dynamic check
4887 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4891 Next_Index (Subt_Index);
4892 Next_Index (Target_Index);
4895 -- Finally, mark whether the subtype involves dynamic checks
4897 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4902 -- Make sure that generic actual types are properly frozen. The subtype
4903 -- is marked as a generic actual type when the enclosing instance is
4904 -- analyzed, so here we identify the subtype from the tree structure.
4907 and then Is_Generic_Actual_Type (Id)
4908 and then In_Instance
4909 and then not Comes_From_Source (N)
4910 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4911 and then Is_Frozen (T)
4913 Freeze_Before (N, Id);
4916 Set_Optimize_Alignment_Flags (Id);
4917 Check_Eliminated (Id);
4920 if Has_Aspects (N) then
4921 Analyze_Aspect_Specifications (N, Id);
4924 Analyze_Dimension (N);
4925 end Analyze_Subtype_Declaration;
4927 --------------------------------
4928 -- Analyze_Subtype_Indication --
4929 --------------------------------
4931 procedure Analyze_Subtype_Indication (N : Node_Id) is
4932 T : constant Entity_Id := Subtype_Mark (N);
4933 R : constant Node_Id := Range_Expression (Constraint (N));
4940 Set_Etype (N, Etype (R));
4941 Resolve (R, Entity (T));
4943 Set_Error_Posted (R);
4944 Set_Error_Posted (T);
4946 end Analyze_Subtype_Indication;
4948 --------------------------
4949 -- Analyze_Variant_Part --
4950 --------------------------
4952 procedure Analyze_Variant_Part (N : Node_Id) is
4953 Discr_Name : Node_Id;
4954 Discr_Type : Entity_Id;
4956 procedure Process_Variant (A : Node_Id);
4957 -- Analyze declarations for a single variant
4959 package Analyze_Variant_Choices is
4960 new Generic_Analyze_Choices (Process_Variant);
4961 use Analyze_Variant_Choices;
4963 ---------------------
4964 -- Process_Variant --
4965 ---------------------
4967 procedure Process_Variant (A : Node_Id) is
4968 CL : constant Node_Id := Component_List (A);
4970 if not Null_Present (CL) then
4971 Analyze_Declarations (Component_Items (CL));
4973 if Present (Variant_Part (CL)) then
4974 Analyze (Variant_Part (CL));
4977 end Process_Variant;
4979 -- Start of processing for Analyze_Variant_Part
4982 Discr_Name := Name (N);
4983 Analyze (Discr_Name);
4985 -- If Discr_Name bad, get out (prevent cascaded errors)
4987 if Etype (Discr_Name) = Any_Type then
4991 -- Check invalid discriminant in variant part
4993 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4994 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4997 Discr_Type := Etype (Entity (Discr_Name));
4999 if not Is_Discrete_Type (Discr_Type) then
5001 ("discriminant in a variant part must be of a discrete type",
5006 -- Now analyze the choices, which also analyzes the declarations that
5007 -- are associated with each choice.
5009 Analyze_Choices (Variants (N), Discr_Type);
5011 -- Note: we used to instantiate and call Check_Choices here to check
5012 -- that the choices covered the discriminant, but it's too early to do
5013 -- that because of statically predicated subtypes, whose analysis may
5014 -- be deferred to their freeze point which may be as late as the freeze
5015 -- point of the containing record. So this call is now to be found in
5016 -- Freeze_Record_Declaration.
5018 end Analyze_Variant_Part;
5020 ----------------------------
5021 -- Array_Type_Declaration --
5022 ----------------------------
5024 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5025 Component_Def : constant Node_Id := Component_Definition (Def);
5026 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5027 Element_Type : Entity_Id;
5028 Implicit_Base : Entity_Id;
5030 Related_Id : Entity_Id := Empty;
5032 P : constant Node_Id := Parent (Def);
5036 if Nkind (Def) = N_Constrained_Array_Definition then
5037 Index := First (Discrete_Subtype_Definitions (Def));
5039 Index := First (Subtype_Marks (Def));
5042 -- Find proper names for the implicit types which may be public. In case
5043 -- of anonymous arrays we use the name of the first object of that type
5047 Related_Id := Defining_Identifier (P);
5053 while Present (Index) loop
5056 -- Test for odd case of trying to index a type by the type itself
5058 if Is_Entity_Name (Index) and then Entity (Index) = T then
5059 Error_Msg_N ("type& cannot be indexed by itself", Index);
5060 Set_Entity (Index, Standard_Boolean);
5061 Set_Etype (Index, Standard_Boolean);
5064 -- Check SPARK restriction requiring a subtype mark
5066 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5067 Check_SPARK_Restriction ("subtype mark required", Index);
5070 -- Add a subtype declaration for each index of private array type
5071 -- declaration whose etype is also private. For example:
5074 -- type Index is private;
5076 -- type Table is array (Index) of ...
5079 -- This is currently required by the expander for the internally
5080 -- generated equality subprogram of records with variant parts in
5081 -- which the etype of some component is such private type.
5083 if Ekind (Current_Scope) = E_Package
5084 and then In_Private_Part (Current_Scope)
5085 and then Has_Private_Declaration (Etype (Index))
5088 Loc : constant Source_Ptr := Sloc (Def);
5093 New_E := Make_Temporary (Loc, 'T');
5094 Set_Is_Internal (New_E);
5097 Make_Subtype_Declaration (Loc,
5098 Defining_Identifier => New_E,
5099 Subtype_Indication =>
5100 New_Occurrence_Of (Etype (Index), Loc));
5102 Insert_Before (Parent (Def), Decl);
5104 Set_Etype (Index, New_E);
5106 -- If the index is a range the Entity attribute is not
5107 -- available. Example:
5110 -- type T is private;
5112 -- type T is new Natural;
5113 -- Table : array (T(1) .. T(10)) of Boolean;
5116 if Nkind (Index) /= N_Range then
5117 Set_Entity (Index, New_E);
5122 Make_Index (Index, P, Related_Id, Nb_Index);
5124 -- Check error of subtype with predicate for index type
5126 Bad_Predicated_Subtype_Use
5127 ("subtype& has predicate, not allowed as index subtype",
5128 Index, Etype (Index));
5130 -- Move to next index
5133 Nb_Index := Nb_Index + 1;
5136 -- Process subtype indication if one is present
5138 if Present (Component_Typ) then
5139 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5141 Set_Etype (Component_Typ, Element_Type);
5143 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5144 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
5147 -- Ada 2005 (AI-230): Access Definition case
5149 else pragma Assert (Present (Access_Definition (Component_Def)));
5151 -- Indicate that the anonymous access type is created by the
5152 -- array type declaration.
5154 Element_Type := Access_Definition
5156 N => Access_Definition (Component_Def));
5157 Set_Is_Local_Anonymous_Access (Element_Type);
5159 -- Propagate the parent. This field is needed if we have to generate
5160 -- the master_id associated with an anonymous access to task type
5161 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5163 Set_Parent (Element_Type, Parent (T));
5165 -- Ada 2005 (AI-230): In case of components that are anonymous access
5166 -- types the level of accessibility depends on the enclosing type
5169 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5171 -- Ada 2005 (AI-254)
5174 CD : constant Node_Id :=
5175 Access_To_Subprogram_Definition
5176 (Access_Definition (Component_Def));
5178 if Present (CD) and then Protected_Present (CD) then
5180 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5185 -- Constrained array case
5188 T := Create_Itype (E_Void, P, Related_Id, 'T');
5191 if Nkind (Def) = N_Constrained_Array_Definition then
5193 -- Establish Implicit_Base as unconstrained base type
5195 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5197 Set_Etype (Implicit_Base, Implicit_Base);
5198 Set_Scope (Implicit_Base, Current_Scope);
5199 Set_Has_Delayed_Freeze (Implicit_Base);
5200 Set_Default_SSO (Implicit_Base);
5202 -- The constrained array type is a subtype of the unconstrained one
5204 Set_Ekind (T, E_Array_Subtype);
5205 Init_Size_Align (T);
5206 Set_Etype (T, Implicit_Base);
5207 Set_Scope (T, Current_Scope);
5208 Set_Is_Constrained (T, True);
5209 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
5210 Set_Has_Delayed_Freeze (T);
5212 -- Complete setup of implicit base type
5214 Set_First_Index (Implicit_Base, First_Index (T));
5215 Set_Component_Type (Implicit_Base, Element_Type);
5216 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5217 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5218 Set_Component_Size (Implicit_Base, Uint_0);
5219 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5220 Set_Has_Controlled_Component
5221 (Implicit_Base, Has_Controlled_Component
5223 or else Is_Controlled
5225 Set_Finalize_Storage_Only
5226 (Implicit_Base, Finalize_Storage_Only
5229 -- Unconstrained array case
5232 Set_Ekind (T, E_Array_Type);
5233 Init_Size_Align (T);
5235 Set_Scope (T, Current_Scope);
5236 Set_Component_Size (T, Uint_0);
5237 Set_Is_Constrained (T, False);
5238 Set_First_Index (T, First (Subtype_Marks (Def)));
5239 Set_Has_Delayed_Freeze (T, True);
5240 Set_Has_Task (T, Has_Task (Element_Type));
5241 Set_Has_Protected (T, Has_Protected (Element_Type));
5242 Set_Has_Controlled_Component (T, Has_Controlled_Component
5245 Is_Controlled (Element_Type));
5246 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5248 Set_Default_SSO (T);
5251 -- Common attributes for both cases
5253 Set_Component_Type (Base_Type (T), Element_Type);
5254 Set_Packed_Array_Impl_Type (T, Empty);
5256 if Aliased_Present (Component_Definition (Def)) then
5257 Check_SPARK_Restriction
5258 ("aliased is not allowed", Component_Definition (Def));
5259 Set_Has_Aliased_Components (Etype (T));
5262 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5263 -- array type to ensure that objects of this type are initialized.
5265 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5266 Set_Can_Never_Be_Null (T);
5268 if Null_Exclusion_Present (Component_Definition (Def))
5270 -- No need to check itypes because in their case this check was
5271 -- done at their point of creation
5273 and then not Is_Itype (Element_Type)
5276 ("`NOT NULL` not allowed (null already excluded)",
5277 Subtype_Indication (Component_Definition (Def)));
5281 Priv := Private_Component (Element_Type);
5283 if Present (Priv) then
5285 -- Check for circular definitions
5287 if Priv = Any_Type then
5288 Set_Component_Type (Etype (T), Any_Type);
5290 -- There is a gap in the visibility of operations on the composite
5291 -- type only if the component type is defined in a different scope.
5293 elsif Scope (Priv) = Current_Scope then
5296 elsif Is_Limited_Type (Priv) then
5297 Set_Is_Limited_Composite (Etype (T));
5298 Set_Is_Limited_Composite (T);
5300 Set_Is_Private_Composite (Etype (T));
5301 Set_Is_Private_Composite (T);
5305 -- A syntax error in the declaration itself may lead to an empty index
5306 -- list, in which case do a minimal patch.
5308 if No (First_Index (T)) then
5309 Error_Msg_N ("missing index definition in array type declaration", T);
5312 Indexes : constant List_Id :=
5313 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5315 Set_Discrete_Subtype_Definitions (Def, Indexes);
5316 Set_First_Index (T, First (Indexes));
5321 -- Create a concatenation operator for the new type. Internal array
5322 -- types created for packed entities do not need such, they are
5323 -- compatible with the user-defined type.
5325 if Number_Dimensions (T) = 1
5326 and then not Is_Packed_Array_Impl_Type (T)
5328 New_Concatenation_Op (T);
5331 -- In the case of an unconstrained array the parser has already verified
5332 -- that all the indexes are unconstrained but we still need to make sure
5333 -- that the element type is constrained.
5335 if Is_Indefinite_Subtype (Element_Type) then
5337 ("unconstrained element type in array declaration",
5338 Subtype_Indication (Component_Def));
5340 elsif Is_Abstract_Type (Element_Type) then
5342 ("the type of a component cannot be abstract",
5343 Subtype_Indication (Component_Def));
5346 -- There may be an invariant declared for the component type, but
5347 -- the construction of the component invariant checking procedure
5348 -- takes place during expansion.
5349 end Array_Type_Declaration;
5351 ------------------------------------------------------
5352 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5353 ------------------------------------------------------
5355 function Replace_Anonymous_Access_To_Protected_Subprogram
5356 (N : Node_Id) return Entity_Id
5358 Loc : constant Source_Ptr := Sloc (N);
5360 Curr_Scope : constant Scope_Stack_Entry :=
5361 Scope_Stack.Table (Scope_Stack.Last);
5363 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5366 -- Access definition in declaration
5369 -- Object definition or formal definition with an access definition
5372 -- Declaration of anonymous access to subprogram type
5375 -- Original specification in access to subprogram
5380 Set_Is_Internal (Anon);
5383 when N_Component_Declaration |
5384 N_Unconstrained_Array_Definition |
5385 N_Constrained_Array_Definition =>
5386 Comp := Component_Definition (N);
5387 Acc := Access_Definition (Comp);
5389 when N_Discriminant_Specification =>
5390 Comp := Discriminant_Type (N);
5393 when N_Parameter_Specification =>
5394 Comp := Parameter_Type (N);
5397 when N_Access_Function_Definition =>
5398 Comp := Result_Definition (N);
5401 when N_Object_Declaration =>
5402 Comp := Object_Definition (N);
5405 when N_Function_Specification =>
5406 Comp := Result_Definition (N);
5410 raise Program_Error;
5413 Spec := Access_To_Subprogram_Definition (Acc);
5416 Make_Full_Type_Declaration (Loc,
5417 Defining_Identifier => Anon,
5418 Type_Definition => Copy_Separate_Tree (Spec));
5420 Mark_Rewrite_Insertion (Decl);
5422 -- In ASIS mode, analyze the profile on the original node, because
5423 -- the separate copy does not provide enough links to recover the
5424 -- original tree. Analysis is limited to type annotations, within
5425 -- a temporary scope that serves as an anonymous subprogram to collect
5426 -- otherwise useless temporaries and itypes.
5430 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5433 if Nkind (Spec) = N_Access_Function_Definition then
5434 Set_Ekind (Typ, E_Function);
5436 Set_Ekind (Typ, E_Procedure);
5439 Set_Parent (Typ, N);
5440 Set_Scope (Typ, Current_Scope);
5443 Process_Formals (Parameter_Specifications (Spec), Spec);
5445 if Nkind (Spec) = N_Access_Function_Definition then
5447 Def : constant Node_Id := Result_Definition (Spec);
5450 -- The result might itself be an anonymous access type, so
5453 if Nkind (Def) = N_Access_Definition then
5454 if Present (Access_To_Subprogram_Definition (Def)) then
5457 Replace_Anonymous_Access_To_Protected_Subprogram
5460 Find_Type (Subtype_Mark (Def));
5473 -- Insert the new declaration in the nearest enclosing scope. If the
5474 -- node is a body and N is its return type, the declaration belongs in
5475 -- the enclosing scope.
5479 if Nkind (P) = N_Subprogram_Body
5480 and then Nkind (N) = N_Function_Specification
5485 while Present (P) and then not Has_Declarations (P) loop
5489 pragma Assert (Present (P));
5491 if Nkind (P) = N_Package_Specification then
5492 Prepend (Decl, Visible_Declarations (P));
5494 Prepend (Decl, Declarations (P));
5497 -- Replace the anonymous type with an occurrence of the new declaration.
5498 -- In all cases the rewritten node does not have the null-exclusion
5499 -- attribute because (if present) it was already inherited by the
5500 -- anonymous entity (Anon). Thus, in case of components we do not
5501 -- inherit this attribute.
5503 if Nkind (N) = N_Parameter_Specification then
5504 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5505 Set_Etype (Defining_Identifier (N), Anon);
5506 Set_Null_Exclusion_Present (N, False);
5508 elsif Nkind (N) = N_Object_Declaration then
5509 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5510 Set_Etype (Defining_Identifier (N), Anon);
5512 elsif Nkind (N) = N_Access_Function_Definition then
5513 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5515 elsif Nkind (N) = N_Function_Specification then
5516 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5517 Set_Etype (Defining_Unit_Name (N), Anon);
5521 Make_Component_Definition (Loc,
5522 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5525 Mark_Rewrite_Insertion (Comp);
5527 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5531 -- Temporarily remove the current scope (record or subprogram) from
5532 -- the stack to add the new declarations to the enclosing scope.
5534 Scope_Stack.Decrement_Last;
5536 Set_Is_Itype (Anon);
5537 Scope_Stack.Append (Curr_Scope);
5540 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5541 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5543 end Replace_Anonymous_Access_To_Protected_Subprogram;
5545 -------------------------------
5546 -- Build_Derived_Access_Type --
5547 -------------------------------
5549 procedure Build_Derived_Access_Type
5551 Parent_Type : Entity_Id;
5552 Derived_Type : Entity_Id)
5554 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5556 Desig_Type : Entity_Id;
5558 Discr_Con_Elist : Elist_Id;
5559 Discr_Con_El : Elmt_Id;
5563 -- Set the designated type so it is available in case this is an access
5564 -- to a self-referential type, e.g. a standard list type with a next
5565 -- pointer. Will be reset after subtype is built.
5567 Set_Directly_Designated_Type
5568 (Derived_Type, Designated_Type (Parent_Type));
5570 Subt := Process_Subtype (S, N);
5572 if Nkind (S) /= N_Subtype_Indication
5573 and then Subt /= Base_Type (Subt)
5575 Set_Ekind (Derived_Type, E_Access_Subtype);
5578 if Ekind (Derived_Type) = E_Access_Subtype then
5580 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5581 Ibase : constant Entity_Id :=
5582 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5583 Svg_Chars : constant Name_Id := Chars (Ibase);
5584 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5587 Copy_Node (Pbase, Ibase);
5589 Set_Chars (Ibase, Svg_Chars);
5590 Set_Next_Entity (Ibase, Svg_Next_E);
5591 Set_Sloc (Ibase, Sloc (Derived_Type));
5592 Set_Scope (Ibase, Scope (Derived_Type));
5593 Set_Freeze_Node (Ibase, Empty);
5594 Set_Is_Frozen (Ibase, False);
5595 Set_Comes_From_Source (Ibase, False);
5596 Set_Is_First_Subtype (Ibase, False);
5598 Set_Etype (Ibase, Pbase);
5599 Set_Etype (Derived_Type, Ibase);
5603 Set_Directly_Designated_Type
5604 (Derived_Type, Designated_Type (Subt));
5606 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5607 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5608 Set_Size_Info (Derived_Type, Parent_Type);
5609 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5610 Set_Depends_On_Private (Derived_Type,
5611 Has_Private_Component (Derived_Type));
5612 Conditional_Delay (Derived_Type, Subt);
5614 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5615 -- that it is not redundant.
5617 if Null_Exclusion_Present (Type_Definition (N)) then
5618 Set_Can_Never_Be_Null (Derived_Type);
5620 -- What is with the "AND THEN FALSE" here ???
5622 if Can_Never_Be_Null (Parent_Type)
5626 ("`NOT NULL` not allowed (& already excludes null)",
5630 elsif Can_Never_Be_Null (Parent_Type) then
5631 Set_Can_Never_Be_Null (Derived_Type);
5634 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5635 -- the root type for this information.
5637 -- Apply range checks to discriminants for derived record case
5638 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5640 Desig_Type := Designated_Type (Derived_Type);
5641 if Is_Composite_Type (Desig_Type)
5642 and then (not Is_Array_Type (Desig_Type))
5643 and then Has_Discriminants (Desig_Type)
5644 and then Base_Type (Desig_Type) /= Desig_Type
5646 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5647 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5649 Discr := First_Discriminant (Base_Type (Desig_Type));
5650 while Present (Discr_Con_El) loop
5651 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5652 Next_Elmt (Discr_Con_El);
5653 Next_Discriminant (Discr);
5656 end Build_Derived_Access_Type;
5658 ------------------------------
5659 -- Build_Derived_Array_Type --
5660 ------------------------------
5662 procedure Build_Derived_Array_Type
5664 Parent_Type : Entity_Id;
5665 Derived_Type : Entity_Id)
5667 Loc : constant Source_Ptr := Sloc (N);
5668 Tdef : constant Node_Id := Type_Definition (N);
5669 Indic : constant Node_Id := Subtype_Indication (Tdef);
5670 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5671 Implicit_Base : Entity_Id;
5672 New_Indic : Node_Id;
5674 procedure Make_Implicit_Base;
5675 -- If the parent subtype is constrained, the derived type is a subtype
5676 -- of an implicit base type derived from the parent base.
5678 ------------------------
5679 -- Make_Implicit_Base --
5680 ------------------------
5682 procedure Make_Implicit_Base is
5685 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5687 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5688 Set_Etype (Implicit_Base, Parent_Base);
5690 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5691 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5693 Set_Has_Delayed_Freeze (Implicit_Base, True);
5694 end Make_Implicit_Base;
5696 -- Start of processing for Build_Derived_Array_Type
5699 if not Is_Constrained (Parent_Type) then
5700 if Nkind (Indic) /= N_Subtype_Indication then
5701 Set_Ekind (Derived_Type, E_Array_Type);
5703 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5704 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5706 Set_Has_Delayed_Freeze (Derived_Type, True);
5710 Set_Etype (Derived_Type, Implicit_Base);
5713 Make_Subtype_Declaration (Loc,
5714 Defining_Identifier => Derived_Type,
5715 Subtype_Indication =>
5716 Make_Subtype_Indication (Loc,
5717 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5718 Constraint => Constraint (Indic)));
5720 Rewrite (N, New_Indic);
5725 if Nkind (Indic) /= N_Subtype_Indication then
5728 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5729 Set_Etype (Derived_Type, Implicit_Base);
5730 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5733 Error_Msg_N ("illegal constraint on constrained type", Indic);
5737 -- If parent type is not a derived type itself, and is declared in
5738 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5739 -- the new type's concatenation operator since Derive_Subprograms
5740 -- will not inherit the parent's operator. If the parent type is
5741 -- unconstrained, the operator is of the unconstrained base type.
5743 if Number_Dimensions (Parent_Type) = 1
5744 and then not Is_Limited_Type (Parent_Type)
5745 and then not Is_Derived_Type (Parent_Type)
5746 and then not Is_Package_Or_Generic_Package
5747 (Scope (Base_Type (Parent_Type)))
5749 if not Is_Constrained (Parent_Type)
5750 and then Is_Constrained (Derived_Type)
5752 New_Concatenation_Op (Implicit_Base);
5754 New_Concatenation_Op (Derived_Type);
5757 end Build_Derived_Array_Type;
5759 -----------------------------------
5760 -- Build_Derived_Concurrent_Type --
5761 -----------------------------------
5763 procedure Build_Derived_Concurrent_Type
5765 Parent_Type : Entity_Id;
5766 Derived_Type : Entity_Id)
5768 Loc : constant Source_Ptr := Sloc (N);
5770 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5771 Corr_Decl : Node_Id;
5772 Corr_Decl_Needed : Boolean;
5773 -- If the derived type has fewer discriminants than its parent, the
5774 -- corresponding record is also a derived type, in order to account for
5775 -- the bound discriminants. We create a full type declaration for it in
5778 Constraint_Present : constant Boolean :=
5779 Nkind (Subtype_Indication (Type_Definition (N))) =
5780 N_Subtype_Indication;
5782 D_Constraint : Node_Id;
5783 New_Constraint : Elist_Id;
5784 Old_Disc : Entity_Id;
5785 New_Disc : Entity_Id;
5789 Set_Stored_Constraint (Derived_Type, No_Elist);
5790 Corr_Decl_Needed := False;
5793 if Present (Discriminant_Specifications (N))
5794 and then Constraint_Present
5796 Old_Disc := First_Discriminant (Parent_Type);
5797 New_Disc := First (Discriminant_Specifications (N));
5798 while Present (New_Disc) and then Present (Old_Disc) loop
5799 Next_Discriminant (Old_Disc);
5804 if Present (Old_Disc) and then Expander_Active then
5806 -- The new type has fewer discriminants, so we need to create a new
5807 -- corresponding record, which is derived from the corresponding
5808 -- record of the parent, and has a stored constraint that captures
5809 -- the values of the discriminant constraints. The corresponding
5810 -- record is needed only if expander is active and code generation is
5813 -- The type declaration for the derived corresponding record has the
5814 -- same discriminant part and constraints as the current declaration.
5815 -- Copy the unanalyzed tree to build declaration.
5817 Corr_Decl_Needed := True;
5818 New_N := Copy_Separate_Tree (N);
5821 Make_Full_Type_Declaration (Loc,
5822 Defining_Identifier => Corr_Record,
5823 Discriminant_Specifications =>
5824 Discriminant_Specifications (New_N),
5826 Make_Derived_Type_Definition (Loc,
5827 Subtype_Indication =>
5828 Make_Subtype_Indication (Loc,
5831 (Corresponding_Record_Type (Parent_Type), Loc),
5834 (Subtype_Indication (Type_Definition (New_N))))));
5837 -- Copy Storage_Size and Relative_Deadline variables if task case
5839 if Is_Task_Type (Parent_Type) then
5840 Set_Storage_Size_Variable (Derived_Type,
5841 Storage_Size_Variable (Parent_Type));
5842 Set_Relative_Deadline_Variable (Derived_Type,
5843 Relative_Deadline_Variable (Parent_Type));
5846 if Present (Discriminant_Specifications (N)) then
5847 Push_Scope (Derived_Type);
5848 Check_Or_Process_Discriminants (N, Derived_Type);
5850 if Constraint_Present then
5852 Expand_To_Stored_Constraint
5854 Build_Discriminant_Constraints
5856 Subtype_Indication (Type_Definition (N)), True));
5861 elsif Constraint_Present then
5863 -- Build constrained subtype, copying the constraint, and derive
5864 -- from it to create a derived constrained type.
5867 Loc : constant Source_Ptr := Sloc (N);
5868 Anon : constant Entity_Id :=
5869 Make_Defining_Identifier (Loc,
5870 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5875 Make_Subtype_Declaration (Loc,
5876 Defining_Identifier => Anon,
5877 Subtype_Indication =>
5878 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
5879 Insert_Before (N, Decl);
5882 Rewrite (Subtype_Indication (Type_Definition (N)),
5883 New_Occurrence_Of (Anon, Loc));
5884 Set_Analyzed (Derived_Type, False);
5890 -- By default, operations and private data are inherited from parent.
5891 -- However, in the presence of bound discriminants, a new corresponding
5892 -- record will be created, see below.
5894 Set_Has_Discriminants
5895 (Derived_Type, Has_Discriminants (Parent_Type));
5896 Set_Corresponding_Record_Type
5897 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5899 -- Is_Constrained is set according the parent subtype, but is set to
5900 -- False if the derived type is declared with new discriminants.
5904 (Is_Constrained (Parent_Type) or else Constraint_Present)
5905 and then not Present (Discriminant_Specifications (N)));
5907 if Constraint_Present then
5908 if not Has_Discriminants (Parent_Type) then
5909 Error_Msg_N ("untagged parent must have discriminants", N);
5911 elsif Present (Discriminant_Specifications (N)) then
5913 -- Verify that new discriminants are used to constrain old ones
5918 (Constraint (Subtype_Indication (Type_Definition (N)))));
5920 Old_Disc := First_Discriminant (Parent_Type);
5922 while Present (D_Constraint) loop
5923 if Nkind (D_Constraint) /= N_Discriminant_Association then
5925 -- Positional constraint. If it is a reference to a new
5926 -- discriminant, it constrains the corresponding old one.
5928 if Nkind (D_Constraint) = N_Identifier then
5929 New_Disc := First_Discriminant (Derived_Type);
5930 while Present (New_Disc) loop
5931 exit when Chars (New_Disc) = Chars (D_Constraint);
5932 Next_Discriminant (New_Disc);
5935 if Present (New_Disc) then
5936 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5940 Next_Discriminant (Old_Disc);
5942 -- if this is a named constraint, search by name for the old
5943 -- discriminants constrained by the new one.
5945 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5947 -- Find new discriminant with that name
5949 New_Disc := First_Discriminant (Derived_Type);
5950 while Present (New_Disc) loop
5952 Chars (New_Disc) = Chars (Expression (D_Constraint));
5953 Next_Discriminant (New_Disc);
5956 if Present (New_Disc) then
5958 -- Verify that new discriminant renames some discriminant
5959 -- of the parent type, and associate the new discriminant
5960 -- with one or more old ones that it renames.
5966 Selector := First (Selector_Names (D_Constraint));
5967 while Present (Selector) loop
5968 Old_Disc := First_Discriminant (Parent_Type);
5969 while Present (Old_Disc) loop
5970 exit when Chars (Old_Disc) = Chars (Selector);
5971 Next_Discriminant (Old_Disc);
5974 if Present (Old_Disc) then
5975 Set_Corresponding_Discriminant
5976 (New_Disc, Old_Disc);
5985 Next (D_Constraint);
5988 New_Disc := First_Discriminant (Derived_Type);
5989 while Present (New_Disc) loop
5990 if No (Corresponding_Discriminant (New_Disc)) then
5992 ("new discriminant& must constrain old one", N, New_Disc);
5995 Subtypes_Statically_Compatible
5997 Etype (Corresponding_Discriminant (New_Disc)))
6000 ("& not statically compatible with parent discriminant",
6004 Next_Discriminant (New_Disc);
6008 elsif Present (Discriminant_Specifications (N)) then
6010 ("missing discriminant constraint in untagged derivation", N);
6013 -- The entity chain of the derived type includes the new discriminants
6014 -- but shares operations with the parent.
6016 if Present (Discriminant_Specifications (N)) then
6017 Old_Disc := First_Discriminant (Parent_Type);
6018 while Present (Old_Disc) loop
6019 if No (Next_Entity (Old_Disc))
6020 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6023 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6027 Next_Discriminant (Old_Disc);
6031 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6032 if Has_Discriminants (Parent_Type) then
6033 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6034 Set_Discriminant_Constraint (
6035 Derived_Type, Discriminant_Constraint (Parent_Type));
6039 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6041 Set_Has_Completion (Derived_Type);
6043 if Corr_Decl_Needed then
6044 Set_Stored_Constraint (Derived_Type, New_Constraint);
6045 Insert_After (N, Corr_Decl);
6046 Analyze (Corr_Decl);
6047 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6049 end Build_Derived_Concurrent_Type;
6051 ------------------------------------
6052 -- Build_Derived_Enumeration_Type --
6053 ------------------------------------
6055 procedure Build_Derived_Enumeration_Type
6057 Parent_Type : Entity_Id;
6058 Derived_Type : Entity_Id)
6060 Loc : constant Source_Ptr := Sloc (N);
6061 Def : constant Node_Id := Type_Definition (N);
6062 Indic : constant Node_Id := Subtype_Indication (Def);
6063 Implicit_Base : Entity_Id;
6064 Literal : Entity_Id;
6065 New_Lit : Entity_Id;
6066 Literals_List : List_Id;
6067 Type_Decl : Node_Id;
6069 Rang_Expr : Node_Id;
6072 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6073 -- not have explicit literals lists we need to process types derived
6074 -- from them specially. This is handled by Derived_Standard_Character.
6075 -- If the parent type is a generic type, there are no literals either,
6076 -- and we construct the same skeletal representation as for the generic
6079 if Is_Standard_Character_Type (Parent_Type) then
6080 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6082 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6088 if Nkind (Indic) /= N_Subtype_Indication then
6090 Make_Attribute_Reference (Loc,
6091 Attribute_Name => Name_First,
6092 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6093 Set_Etype (Lo, Derived_Type);
6096 Make_Attribute_Reference (Loc,
6097 Attribute_Name => Name_Last,
6098 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6099 Set_Etype (Hi, Derived_Type);
6101 Set_Scalar_Range (Derived_Type,
6107 -- Analyze subtype indication and verify compatibility
6108 -- with parent type.
6110 if Base_Type (Process_Subtype (Indic, N)) /=
6111 Base_Type (Parent_Type)
6114 ("illegal constraint for formal discrete type", N);
6120 -- If a constraint is present, analyze the bounds to catch
6121 -- premature usage of the derived literals.
6123 if Nkind (Indic) = N_Subtype_Indication
6124 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6126 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6127 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6130 -- Introduce an implicit base type for the derived type even if there
6131 -- is no constraint attached to it, since this seems closer to the
6132 -- Ada semantics. Build a full type declaration tree for the derived
6133 -- type using the implicit base type as the defining identifier. The
6134 -- build a subtype declaration tree which applies the constraint (if
6135 -- any) have it replace the derived type declaration.
6137 Literal := First_Literal (Parent_Type);
6138 Literals_List := New_List;
6139 while Present (Literal)
6140 and then Ekind (Literal) = E_Enumeration_Literal
6142 -- Literals of the derived type have the same representation as
6143 -- those of the parent type, but this representation can be
6144 -- overridden by an explicit representation clause. Indicate
6145 -- that there is no explicit representation given yet. These
6146 -- derived literals are implicit operations of the new type,
6147 -- and can be overridden by explicit ones.
6149 if Nkind (Literal) = N_Defining_Character_Literal then
6151 Make_Defining_Character_Literal (Loc, Chars (Literal));
6153 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6156 Set_Ekind (New_Lit, E_Enumeration_Literal);
6157 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6158 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6159 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6160 Set_Alias (New_Lit, Literal);
6161 Set_Is_Known_Valid (New_Lit, True);
6163 Append (New_Lit, Literals_List);
6164 Next_Literal (Literal);
6168 Make_Defining_Identifier (Sloc (Derived_Type),
6169 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6171 -- Indicate the proper nature of the derived type. This must be done
6172 -- before analysis of the literals, to recognize cases when a literal
6173 -- may be hidden by a previous explicit function definition (cf.
6176 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6177 Set_Etype (Derived_Type, Implicit_Base);
6180 Make_Full_Type_Declaration (Loc,
6181 Defining_Identifier => Implicit_Base,
6182 Discriminant_Specifications => No_List,
6184 Make_Enumeration_Type_Definition (Loc, Literals_List));
6186 Mark_Rewrite_Insertion (Type_Decl);
6187 Insert_Before (N, Type_Decl);
6188 Analyze (Type_Decl);
6190 -- After the implicit base is analyzed its Etype needs to be changed
6191 -- to reflect the fact that it is derived from the parent type which
6192 -- was ignored during analysis. We also set the size at this point.
6194 Set_Etype (Implicit_Base, Parent_Type);
6196 Set_Size_Info (Implicit_Base, Parent_Type);
6197 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6198 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6200 -- Copy other flags from parent type
6202 Set_Has_Non_Standard_Rep
6203 (Implicit_Base, Has_Non_Standard_Rep
6205 Set_Has_Pragma_Ordered
6206 (Implicit_Base, Has_Pragma_Ordered
6208 Set_Has_Delayed_Freeze (Implicit_Base);
6210 -- Process the subtype indication including a validation check on the
6211 -- constraint, if any. If a constraint is given, its bounds must be
6212 -- implicitly converted to the new type.
6214 if Nkind (Indic) = N_Subtype_Indication then
6216 R : constant Node_Id :=
6217 Range_Expression (Constraint (Indic));
6220 if Nkind (R) = N_Range then
6221 Hi := Build_Scalar_Bound
6222 (High_Bound (R), Parent_Type, Implicit_Base);
6223 Lo := Build_Scalar_Bound
6224 (Low_Bound (R), Parent_Type, Implicit_Base);
6227 -- Constraint is a Range attribute. Replace with explicit
6228 -- mention of the bounds of the prefix, which must be a
6231 Analyze (Prefix (R));
6233 Convert_To (Implicit_Base,
6234 Make_Attribute_Reference (Loc,
6235 Attribute_Name => Name_Last,
6237 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6240 Convert_To (Implicit_Base,
6241 Make_Attribute_Reference (Loc,
6242 Attribute_Name => Name_First,
6244 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6251 (Type_High_Bound (Parent_Type),
6252 Parent_Type, Implicit_Base);
6255 (Type_Low_Bound (Parent_Type),
6256 Parent_Type, Implicit_Base);
6264 -- If we constructed a default range for the case where no range
6265 -- was given, then the expressions in the range must not freeze
6266 -- since they do not correspond to expressions in the source.
6268 if Nkind (Indic) /= N_Subtype_Indication then
6269 Set_Must_Not_Freeze (Lo);
6270 Set_Must_Not_Freeze (Hi);
6271 Set_Must_Not_Freeze (Rang_Expr);
6275 Make_Subtype_Declaration (Loc,
6276 Defining_Identifier => Derived_Type,
6277 Subtype_Indication =>
6278 Make_Subtype_Indication (Loc,
6279 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6281 Make_Range_Constraint (Loc,
6282 Range_Expression => Rang_Expr))));
6286 -- Apply a range check. Since this range expression doesn't have an
6287 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6290 if Nkind (Indic) = N_Subtype_Indication then
6291 Apply_Range_Check (Range_Expression (Constraint (Indic)),
6293 Source_Typ => Entity (Subtype_Mark (Indic)));
6296 end Build_Derived_Enumeration_Type;
6298 --------------------------------
6299 -- Build_Derived_Numeric_Type --
6300 --------------------------------
6302 procedure Build_Derived_Numeric_Type
6304 Parent_Type : Entity_Id;
6305 Derived_Type : Entity_Id)
6307 Loc : constant Source_Ptr := Sloc (N);
6308 Tdef : constant Node_Id := Type_Definition (N);
6309 Indic : constant Node_Id := Subtype_Indication (Tdef);
6310 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6311 No_Constraint : constant Boolean := Nkind (Indic) /=
6312 N_Subtype_Indication;
6313 Implicit_Base : Entity_Id;
6319 -- Process the subtype indication including a validation check on
6320 -- the constraint if any.
6322 Discard_Node (Process_Subtype (Indic, N));
6324 -- Introduce an implicit base type for the derived type even if there
6325 -- is no constraint attached to it, since this seems closer to the Ada
6329 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6331 Set_Etype (Implicit_Base, Parent_Base);
6332 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6333 Set_Size_Info (Implicit_Base, Parent_Base);
6334 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6335 Set_Parent (Implicit_Base, Parent (Derived_Type));
6336 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6338 -- Set RM Size for discrete type or decimal fixed-point type
6339 -- Ordinary fixed-point is excluded, why???
6341 if Is_Discrete_Type (Parent_Base)
6342 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6344 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6347 Set_Has_Delayed_Freeze (Implicit_Base);
6349 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6350 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6352 Set_Scalar_Range (Implicit_Base,
6357 if Has_Infinities (Parent_Base) then
6358 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6361 -- The Derived_Type, which is the entity of the declaration, is a
6362 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6363 -- absence of an explicit constraint.
6365 Set_Etype (Derived_Type, Implicit_Base);
6367 -- If we did not have a constraint, then the Ekind is set from the
6368 -- parent type (otherwise Process_Subtype has set the bounds)
6370 if No_Constraint then
6371 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6374 -- If we did not have a range constraint, then set the range from the
6375 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6378 or else not Has_Range_Constraint (Indic)
6380 Set_Scalar_Range (Derived_Type,
6382 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6383 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6384 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6386 if Has_Infinities (Parent_Type) then
6387 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6390 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6393 Set_Is_Descendent_Of_Address (Derived_Type,
6394 Is_Descendent_Of_Address (Parent_Type));
6395 Set_Is_Descendent_Of_Address (Implicit_Base,
6396 Is_Descendent_Of_Address (Parent_Type));
6398 -- Set remaining type-specific fields, depending on numeric type
6400 if Is_Modular_Integer_Type (Parent_Type) then
6401 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6403 Set_Non_Binary_Modulus
6404 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6407 (Implicit_Base, Is_Known_Valid (Parent_Base));
6409 elsif Is_Floating_Point_Type (Parent_Type) then
6411 -- Digits of base type is always copied from the digits value of
6412 -- the parent base type, but the digits of the derived type will
6413 -- already have been set if there was a constraint present.
6415 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6416 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6418 if No_Constraint then
6419 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6422 elsif Is_Fixed_Point_Type (Parent_Type) then
6424 -- Small of base type and derived type are always copied from the
6425 -- parent base type, since smalls never change. The delta of the
6426 -- base type is also copied from the parent base type. However the
6427 -- delta of the derived type will have been set already if a
6428 -- constraint was present.
6430 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6431 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6432 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6434 if No_Constraint then
6435 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6438 -- The scale and machine radix in the decimal case are always
6439 -- copied from the parent base type.
6441 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6442 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6443 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6445 Set_Machine_Radix_10
6446 (Derived_Type, Machine_Radix_10 (Parent_Base));
6447 Set_Machine_Radix_10
6448 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6450 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6452 if No_Constraint then
6453 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6456 -- the analysis of the subtype_indication sets the
6457 -- digits value of the derived type.
6464 if Is_Integer_Type (Parent_Type) then
6465 Set_Has_Shift_Operator
6466 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6469 -- The type of the bounds is that of the parent type, and they
6470 -- must be converted to the derived type.
6472 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6474 -- The implicit_base should be frozen when the derived type is frozen,
6475 -- but note that it is used in the conversions of the bounds. For fixed
6476 -- types we delay the determination of the bounds until the proper
6477 -- freezing point. For other numeric types this is rejected by GCC, for
6478 -- reasons that are currently unclear (???), so we choose to freeze the
6479 -- implicit base now. In the case of integers and floating point types
6480 -- this is harmless because subsequent representation clauses cannot
6481 -- affect anything, but it is still baffling that we cannot use the
6482 -- same mechanism for all derived numeric types.
6484 -- There is a further complication: actually some representation
6485 -- clauses can affect the implicit base type. For example, attribute
6486 -- definition clauses for stream-oriented attributes need to set the
6487 -- corresponding TSS entries on the base type, and this normally
6488 -- cannot be done after the base type is frozen, so the circuitry in
6489 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6490 -- and not use Set_TSS in this case.
6492 -- There are also consequences for the case of delayed representation
6493 -- aspects for some cases. For example, a Size aspect is delayed and
6494 -- should not be evaluated to the freeze point. This early freezing
6495 -- means that the size attribute evaluation happens too early???
6497 if Is_Fixed_Point_Type (Parent_Type) then
6498 Conditional_Delay (Implicit_Base, Parent_Type);
6500 Freeze_Before (N, Implicit_Base);
6502 end Build_Derived_Numeric_Type;
6504 --------------------------------
6505 -- Build_Derived_Private_Type --
6506 --------------------------------
6508 procedure Build_Derived_Private_Type
6510 Parent_Type : Entity_Id;
6511 Derived_Type : Entity_Id;
6512 Is_Completion : Boolean;
6513 Derive_Subps : Boolean := True)
6515 Loc : constant Source_Ptr := Sloc (N);
6516 Der_Base : Entity_Id;
6518 Full_Decl : Node_Id := Empty;
6519 Full_Der : Entity_Id;
6521 Last_Discr : Entity_Id;
6522 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6523 Swapped : Boolean := False;
6525 procedure Copy_And_Build;
6526 -- Copy derived type declaration, replace parent with its full view,
6527 -- and analyze new declaration.
6529 --------------------
6530 -- Copy_And_Build --
6531 --------------------
6533 procedure Copy_And_Build is
6537 if Ekind (Parent_Type) in Record_Kind
6539 (Ekind (Parent_Type) in Enumeration_Kind
6540 and then not Is_Standard_Character_Type (Parent_Type)
6541 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6543 Full_N := New_Copy_Tree (N);
6544 Insert_After (N, Full_N);
6545 Build_Derived_Type (
6546 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6549 Build_Derived_Type (
6550 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6554 -- Start of processing for Build_Derived_Private_Type
6557 if Is_Tagged_Type (Parent_Type) then
6558 Full_P := Full_View (Parent_Type);
6560 -- A type extension of a type with unknown discriminants is an
6561 -- indefinite type that the back-end cannot handle directly.
6562 -- We treat it as a private type, and build a completion that is
6563 -- derived from the full view of the parent, and hopefully has
6564 -- known discriminants.
6566 -- If the full view of the parent type has an underlying record view,
6567 -- use it to generate the underlying record view of this derived type
6568 -- (required for chains of derivations with unknown discriminants).
6570 -- Minor optimization: we avoid the generation of useless underlying
6571 -- record view entities if the private type declaration has unknown
6572 -- discriminants but its corresponding full view has no
6575 if Has_Unknown_Discriminants (Parent_Type)
6576 and then Present (Full_P)
6577 and then (Has_Discriminants (Full_P)
6578 or else Present (Underlying_Record_View (Full_P)))
6579 and then not In_Open_Scopes (Par_Scope)
6580 and then Expander_Active
6583 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6584 New_Ext : constant Node_Id :=
6586 (Record_Extension_Part (Type_Definition (N)));
6590 Build_Derived_Record_Type
6591 (N, Parent_Type, Derived_Type, Derive_Subps);
6593 -- Build anonymous completion, as a derivation from the full
6594 -- view of the parent. This is not a completion in the usual
6595 -- sense, because the current type is not private.
6598 Make_Full_Type_Declaration (Loc,
6599 Defining_Identifier => Full_Der,
6601 Make_Derived_Type_Definition (Loc,
6602 Subtype_Indication =>
6604 (Subtype_Indication (Type_Definition (N))),
6605 Record_Extension_Part => New_Ext));
6607 -- If the parent type has an underlying record view, use it
6608 -- here to build the new underlying record view.
6610 if Present (Underlying_Record_View (Full_P)) then
6612 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6614 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6615 Underlying_Record_View (Full_P));
6618 Install_Private_Declarations (Par_Scope);
6619 Install_Visible_Declarations (Par_Scope);
6620 Insert_Before (N, Decl);
6622 -- Mark entity as an underlying record view before analysis,
6623 -- to avoid generating the list of its primitive operations
6624 -- (which is not really required for this entity) and thus
6625 -- prevent spurious errors associated with missing overriding
6626 -- of abstract primitives (overridden only for Derived_Type).
6628 Set_Ekind (Full_Der, E_Record_Type);
6629 Set_Is_Underlying_Record_View (Full_Der);
6630 Set_Default_SSO (Full_Der);
6634 pragma Assert (Has_Discriminants (Full_Der)
6635 and then not Has_Unknown_Discriminants (Full_Der));
6637 Uninstall_Declarations (Par_Scope);
6639 -- Freeze the underlying record view, to prevent generation of
6640 -- useless dispatching information, which is simply shared with
6641 -- the real derived type.
6643 Set_Is_Frozen (Full_Der);
6645 -- Set up links between real entity and underlying record view
6647 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6648 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6651 -- If discriminants are known, build derived record
6654 Build_Derived_Record_Type
6655 (N, Parent_Type, Derived_Type, Derive_Subps);
6660 elsif Has_Discriminants (Parent_Type) then
6661 if Present (Full_View (Parent_Type)) then
6662 if not Is_Completion then
6664 -- Copy declaration for subsequent analysis, to provide a
6665 -- completion for what is a private declaration. Indicate that
6666 -- the full type is internally generated.
6668 Full_Decl := New_Copy_Tree (N);
6669 Full_Der := New_Copy (Derived_Type);
6670 Set_Comes_From_Source (Full_Decl, False);
6671 Set_Comes_From_Source (Full_Der, False);
6672 Set_Parent (Full_Der, Full_Decl);
6674 Insert_After (N, Full_Decl);
6677 -- If this is a completion, the full view being built is itself
6678 -- private. We build a subtype of the parent with the same
6679 -- constraints as this full view, to convey to the back end the
6680 -- constrained components and the size of this subtype. If the
6681 -- parent is constrained, its full view can serve as the
6682 -- underlying full view of the derived type.
6684 if No (Discriminant_Specifications (N)) then
6685 if Nkind (Subtype_Indication (Type_Definition (N))) =
6686 N_Subtype_Indication
6688 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6690 elsif Is_Constrained (Full_View (Parent_Type)) then
6691 Set_Underlying_Full_View
6692 (Derived_Type, Full_View (Parent_Type));
6696 -- If there are new discriminants, the parent subtype is
6697 -- constrained by them, but it is not clear how to build
6698 -- the Underlying_Full_View in this case???
6705 -- Build partial view of derived type from partial view of parent
6707 Build_Derived_Record_Type
6708 (N, Parent_Type, Derived_Type, Derive_Subps);
6710 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6711 if not In_Open_Scopes (Par_Scope)
6712 or else not In_Same_Source_Unit (N, Parent_Type)
6714 -- Swap partial and full views temporarily
6716 Install_Private_Declarations (Par_Scope);
6717 Install_Visible_Declarations (Par_Scope);
6721 -- Build full view of derived type from full view of parent which
6722 -- is now installed. Subprograms have been derived on the partial
6723 -- view, the completion does not derive them anew.
6725 if not Is_Tagged_Type (Parent_Type) then
6727 -- If the parent is itself derived from another private type,
6728 -- installing the private declarations has not affected its
6729 -- privacy status, so use its own full view explicitly.
6731 if Is_Private_Type (Parent_Type) then
6732 Build_Derived_Record_Type
6733 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6735 Build_Derived_Record_Type
6736 (Full_Decl, Parent_Type, Full_Der, False);
6740 -- If full view of parent is tagged, the completion inherits
6741 -- the proper primitive operations.
6743 Set_Defining_Identifier (Full_Decl, Full_Der);
6744 Build_Derived_Record_Type
6745 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6748 -- The full declaration has been introduced into the tree and
6749 -- processed in the step above. It should not be analyzed again
6750 -- (when encountered later in the current list of declarations)
6751 -- to prevent spurious name conflicts. The full entity remains
6754 Set_Analyzed (Full_Decl);
6757 Uninstall_Declarations (Par_Scope);
6759 if In_Open_Scopes (Par_Scope) then
6760 Install_Visible_Declarations (Par_Scope);
6764 Der_Base := Base_Type (Derived_Type);
6765 Set_Full_View (Derived_Type, Full_Der);
6766 Set_Full_View (Der_Base, Base_Type (Full_Der));
6768 -- Copy the discriminant list from full view to the partial views
6769 -- (base type and its subtype). Gigi requires that the partial and
6770 -- full views have the same discriminants.
6772 -- Note that since the partial view is pointing to discriminants
6773 -- in the full view, their scope will be that of the full view.
6774 -- This might cause some front end problems and need adjustment???
6776 Discr := First_Discriminant (Base_Type (Full_Der));
6777 Set_First_Entity (Der_Base, Discr);
6780 Last_Discr := Discr;
6781 Next_Discriminant (Discr);
6782 exit when No (Discr);
6785 Set_Last_Entity (Der_Base, Last_Discr);
6787 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6788 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6789 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6792 -- If this is a completion, the derived type stays private and
6793 -- there is no need to create a further full view, except in the
6794 -- unusual case when the derivation is nested within a child unit,
6800 elsif Present (Full_View (Parent_Type))
6801 and then Has_Discriminants (Full_View (Parent_Type))
6803 if Has_Unknown_Discriminants (Parent_Type)
6804 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6805 N_Subtype_Indication
6808 ("cannot constrain type with unknown discriminants",
6809 Subtype_Indication (Type_Definition (N)));
6813 -- If full view of parent is a record type, build full view as a
6814 -- derivation from the parent's full view. Partial view remains
6815 -- private. For code generation and linking, the full view must have
6816 -- the same public status as the partial one. This full view is only
6817 -- needed if the parent type is in an enclosing scope, so that the
6818 -- full view may actually become visible, e.g. in a child unit. This
6819 -- is both more efficient, and avoids order of freezing problems with
6820 -- the added entities.
6822 if not Is_Private_Type (Full_View (Parent_Type))
6823 and then (In_Open_Scopes (Scope (Parent_Type)))
6826 Make_Defining_Identifier (Sloc (Derived_Type),
6827 Chars => Chars (Derived_Type));
6829 Set_Is_Itype (Full_Der);
6830 Set_Has_Private_Declaration (Full_Der);
6831 Set_Has_Private_Declaration (Derived_Type);
6832 Set_Associated_Node_For_Itype (Full_Der, N);
6833 Set_Parent (Full_Der, Parent (Derived_Type));
6834 Set_Full_View (Derived_Type, Full_Der);
6835 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6836 Full_P := Full_View (Parent_Type);
6837 Exchange_Declarations (Parent_Type);
6839 Exchange_Declarations (Full_P);
6842 Build_Derived_Record_Type
6843 (N, Full_View (Parent_Type), Derived_Type,
6844 Derive_Subps => False);
6846 -- Except in the context of the full view of the parent, there
6847 -- are no non-extension aggregates for the derived type.
6849 Set_Has_Private_Ancestor (Derived_Type);
6852 -- In any case, the primitive operations are inherited from the
6853 -- parent type, not from the internal full view.
6855 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6857 if Derive_Subps then
6858 Derive_Subprograms (Parent_Type, Derived_Type);
6862 -- Untagged type, No discriminants on either view
6864 if Nkind (Subtype_Indication (Type_Definition (N))) =
6865 N_Subtype_Indication
6868 ("illegal constraint on type without discriminants", N);
6871 if Present (Discriminant_Specifications (N))
6872 and then Present (Full_View (Parent_Type))
6873 and then not Is_Tagged_Type (Full_View (Parent_Type))
6875 Error_Msg_N ("cannot add discriminants to untagged type", N);
6878 Set_Stored_Constraint (Derived_Type, No_Elist);
6879 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6880 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6881 Set_Has_Controlled_Component
6882 (Derived_Type, Has_Controlled_Component
6885 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6887 if not Is_Controlled (Parent_Type) then
6888 Set_Finalize_Storage_Only
6889 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6892 -- Construct the implicit full view by deriving from full view of the
6893 -- parent type. In order to get proper visibility, we install the
6894 -- parent scope and its declarations.
6896 -- ??? If the parent is untagged private and its completion is
6897 -- tagged, this mechanism will not work because we cannot derive from
6898 -- the tagged full view unless we have an extension.
6900 if Present (Full_View (Parent_Type))
6901 and then not Is_Tagged_Type (Full_View (Parent_Type))
6902 and then not Is_Completion
6905 Make_Defining_Identifier
6906 (Sloc (Derived_Type), Chars (Derived_Type));
6907 Set_Is_Itype (Full_Der);
6908 Set_Has_Private_Declaration (Full_Der);
6909 Set_Has_Private_Declaration (Derived_Type);
6910 Set_Associated_Node_For_Itype (Full_Der, N);
6911 Set_Parent (Full_Der, Parent (Derived_Type));
6912 Set_Full_View (Derived_Type, Full_Der);
6914 if not In_Open_Scopes (Par_Scope) then
6915 Install_Private_Declarations (Par_Scope);
6916 Install_Visible_Declarations (Par_Scope);
6918 Uninstall_Declarations (Par_Scope);
6920 -- If parent scope is open and in another unit, and parent has a
6921 -- completion, then the derivation is taking place in the visible
6922 -- part of a child unit. In that case retrieve the full view of
6923 -- the parent momentarily.
6925 elsif not In_Same_Source_Unit (N, Parent_Type) then
6926 Full_P := Full_View (Parent_Type);
6927 Exchange_Declarations (Parent_Type);
6929 Exchange_Declarations (Full_P);
6931 -- Otherwise it is a local derivation
6937 Set_Scope (Full_Der, Current_Scope);
6938 Set_Is_First_Subtype (Full_Der,
6939 Is_First_Subtype (Derived_Type));
6940 Set_Has_Size_Clause (Full_Der, False);
6941 Set_Has_Alignment_Clause (Full_Der, False);
6942 Set_Next_Entity (Full_Der, Empty);
6943 Set_Has_Delayed_Freeze (Full_Der);
6944 Set_Is_Frozen (Full_Der, False);
6945 Set_Freeze_Node (Full_Der, Empty);
6946 Set_Depends_On_Private (Full_Der,
6947 Has_Private_Component (Full_Der));
6948 Set_Public_Status (Full_Der);
6952 Set_Has_Unknown_Discriminants (Derived_Type,
6953 Has_Unknown_Discriminants (Parent_Type));
6955 if Is_Private_Type (Derived_Type) then
6956 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6959 if Is_Private_Type (Parent_Type)
6960 and then Base_Type (Parent_Type) = Parent_Type
6961 and then In_Open_Scopes (Scope (Parent_Type))
6963 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6965 -- Check for unusual case where a type completed by a private
6966 -- derivation occurs within a package nested in a child unit, and
6967 -- the parent is declared in an ancestor.
6969 if Is_Child_Unit (Scope (Current_Scope))
6970 and then Is_Completion
6971 and then In_Private_Part (Current_Scope)
6972 and then Scope (Parent_Type) /= Current_Scope
6974 -- Note that if the parent has a completion in the private part,
6975 -- (which is itself a derivation from some other private type)
6976 -- it is that completion that is visible, there is no full view
6977 -- available, and no special processing is needed.
6979 and then Present (Full_View (Parent_Type))
6981 -- In this case, the full view of the parent type will become
6982 -- visible in the body of the enclosing child, and only then will
6983 -- the current type be possibly non-private. We build an
6984 -- underlying full view that will be installed when the enclosing
6985 -- child body is compiled.
6988 Make_Defining_Identifier
6989 (Sloc (Derived_Type), Chars (Derived_Type));
6990 Set_Is_Itype (Full_Der);
6991 Build_Itype_Reference (Full_Der, N);
6993 -- The full view will be used to swap entities on entry/exit to
6994 -- the body, and must appear in the entity list for the package.
6996 Append_Entity (Full_Der, Scope (Derived_Type));
6997 Set_Has_Private_Declaration (Full_Der);
6998 Set_Has_Private_Declaration (Derived_Type);
6999 Set_Associated_Node_For_Itype (Full_Der, N);
7000 Set_Parent (Full_Der, Parent (Derived_Type));
7001 Full_P := Full_View (Parent_Type);
7002 Exchange_Declarations (Parent_Type);
7004 Exchange_Declarations (Full_P);
7005 Set_Underlying_Full_View (Derived_Type, Full_Der);
7008 end Build_Derived_Private_Type;
7010 -------------------------------
7011 -- Build_Derived_Record_Type --
7012 -------------------------------
7016 -- Ideally we would like to use the same model of type derivation for
7017 -- tagged and untagged record types. Unfortunately this is not quite
7018 -- possible because the semantics of representation clauses is different
7019 -- for tagged and untagged records under inheritance. Consider the
7022 -- type R (...) is [tagged] record ... end record;
7023 -- type T (...) is new R (...) [with ...];
7025 -- The representation clauses for T can specify a completely different
7026 -- record layout from R's. Hence the same component can be placed in two
7027 -- very different positions in objects of type T and R. If R and T are
7028 -- tagged types, representation clauses for T can only specify the layout
7029 -- of non inherited components, thus components that are common in R and T
7030 -- have the same position in objects of type R and T.
7032 -- This has two implications. The first is that the entire tree for R's
7033 -- declaration needs to be copied for T in the untagged case, so that T
7034 -- can be viewed as a record type of its own with its own representation
7035 -- clauses. The second implication is the way we handle discriminants.
7036 -- Specifically, in the untagged case we need a way to communicate to Gigi
7037 -- what are the real discriminants in the record, while for the semantics
7038 -- we need to consider those introduced by the user to rename the
7039 -- discriminants in the parent type. This is handled by introducing the
7040 -- notion of stored discriminants. See below for more.
7042 -- Fortunately the way regular components are inherited can be handled in
7043 -- the same way in tagged and untagged types.
7045 -- To complicate things a bit more the private view of a private extension
7046 -- cannot be handled in the same way as the full view (for one thing the
7047 -- semantic rules are somewhat different). We will explain what differs
7050 -- 2. DISCRIMINANTS UNDER INHERITANCE
7052 -- The semantic rules governing the discriminants of derived types are
7055 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7056 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7058 -- If parent type has discriminants, then the discriminants that are
7059 -- declared in the derived type are [3.4 (11)]:
7061 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7064 -- o Otherwise, each discriminant of the parent type (implicitly declared
7065 -- in the same order with the same specifications). In this case, the
7066 -- discriminants are said to be "inherited", or if unknown in the parent
7067 -- are also unknown in the derived type.
7069 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7071 -- o The parent subtype shall be constrained;
7073 -- o If the parent type is not a tagged type, then each discriminant of
7074 -- the derived type shall be used in the constraint defining a parent
7075 -- subtype. [Implementation note: This ensures that the new discriminant
7076 -- can share storage with an existing discriminant.]
7078 -- For the derived type each discriminant of the parent type is either
7079 -- inherited, constrained to equal some new discriminant of the derived
7080 -- type, or constrained to the value of an expression.
7082 -- When inherited or constrained to equal some new discriminant, the
7083 -- parent discriminant and the discriminant of the derived type are said
7086 -- If a discriminant of the parent type is constrained to a specific value
7087 -- in the derived type definition, then the discriminant is said to be
7088 -- "specified" by that derived type definition.
7090 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7092 -- We have spoken about stored discriminants in point 1 (introduction)
7093 -- above. There are two sort of stored discriminants: implicit and
7094 -- explicit. As long as the derived type inherits the same discriminants as
7095 -- the root record type, stored discriminants are the same as regular
7096 -- discriminants, and are said to be implicit. However, if any discriminant
7097 -- in the root type was renamed in the derived type, then the derived
7098 -- type will contain explicit stored discriminants. Explicit stored
7099 -- discriminants are discriminants in addition to the semantically visible
7100 -- discriminants defined for the derived type. Stored discriminants are
7101 -- used by Gigi to figure out what are the physical discriminants in
7102 -- objects of the derived type (see precise definition in einfo.ads).
7103 -- As an example, consider the following:
7105 -- type R (D1, D2, D3 : Int) is record ... end record;
7106 -- type T1 is new R;
7107 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7108 -- type T3 is new T2;
7109 -- type T4 (Y : Int) is new T3 (Y, 99);
7111 -- The following table summarizes the discriminants and stored
7112 -- discriminants in R and T1 through T4.
7114 -- Type Discrim Stored Discrim Comment
7115 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7116 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7117 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7118 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7119 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7121 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7122 -- find the corresponding discriminant in the parent type, while
7123 -- Original_Record_Component (abbreviated ORC below), the actual physical
7124 -- component that is renamed. Finally the field Is_Completely_Hidden
7125 -- (abbreviated ICH below) is set for all explicit stored discriminants
7126 -- (see einfo.ads for more info). For the above example this gives:
7128 -- Discrim CD ORC ICH
7129 -- ^^^^^^^ ^^ ^^^ ^^^
7130 -- D1 in R empty itself no
7131 -- D2 in R empty itself no
7132 -- D3 in R empty itself no
7134 -- D1 in T1 D1 in R itself no
7135 -- D2 in T1 D2 in R itself no
7136 -- D3 in T1 D3 in R itself no
7138 -- X1 in T2 D3 in T1 D3 in T2 no
7139 -- X2 in T2 D1 in T1 D1 in T2 no
7140 -- D1 in T2 empty itself yes
7141 -- D2 in T2 empty itself yes
7142 -- D3 in T2 empty itself yes
7144 -- X1 in T3 X1 in T2 D3 in T3 no
7145 -- X2 in T3 X2 in T2 D1 in T3 no
7146 -- D1 in T3 empty itself yes
7147 -- D2 in T3 empty itself yes
7148 -- D3 in T3 empty itself yes
7150 -- Y in T4 X1 in T3 D3 in T3 no
7151 -- D1 in T3 empty itself yes
7152 -- D2 in T3 empty itself yes
7153 -- D3 in T3 empty itself yes
7155 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7157 -- Type derivation for tagged types is fairly straightforward. If no
7158 -- discriminants are specified by the derived type, these are inherited
7159 -- from the parent. No explicit stored discriminants are ever necessary.
7160 -- The only manipulation that is done to the tree is that of adding a
7161 -- _parent field with parent type and constrained to the same constraint
7162 -- specified for the parent in the derived type definition. For instance:
7164 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7165 -- type T1 is new R with null record;
7166 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7168 -- are changed into:
7170 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7171 -- _parent : R (D1, D2, D3);
7174 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7175 -- _parent : T1 (X2, 88, X1);
7178 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7179 -- ORC and ICH fields are:
7181 -- Discrim CD ORC ICH
7182 -- ^^^^^^^ ^^ ^^^ ^^^
7183 -- D1 in R empty itself no
7184 -- D2 in R empty itself no
7185 -- D3 in R empty itself no
7187 -- D1 in T1 D1 in R D1 in R no
7188 -- D2 in T1 D2 in R D2 in R no
7189 -- D3 in T1 D3 in R D3 in R no
7191 -- X1 in T2 D3 in T1 D3 in R no
7192 -- X2 in T2 D1 in T1 D1 in R no
7194 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7196 -- Regardless of whether we dealing with a tagged or untagged type
7197 -- we will transform all derived type declarations of the form
7199 -- type T is new R (...) [with ...];
7201 -- subtype S is R (...);
7202 -- type T is new S [with ...];
7204 -- type BT is new R [with ...];
7205 -- subtype T is BT (...);
7207 -- That is, the base derived type is constrained only if it has no
7208 -- discriminants. The reason for doing this is that GNAT's semantic model
7209 -- assumes that a base type with discriminants is unconstrained.
7211 -- Note that, strictly speaking, the above transformation is not always
7212 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7214 -- procedure B34011A is
7215 -- type REC (D : integer := 0) is record
7220 -- type T6 is new Rec;
7221 -- function F return T6;
7226 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7229 -- The definition of Q6.U is illegal. However transforming Q6.U into
7231 -- type BaseU is new T6;
7232 -- subtype U is BaseU (Q6.F.I)
7234 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7235 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7236 -- the transformation described above.
7238 -- There is another instance where the above transformation is incorrect.
7242 -- type Base (D : Integer) is tagged null record;
7243 -- procedure P (X : Base);
7245 -- type Der is new Base (2) with null record;
7246 -- procedure P (X : Der);
7249 -- Then the above transformation turns this into
7251 -- type Der_Base is new Base with null record;
7252 -- -- procedure P (X : Base) is implicitly inherited here
7253 -- -- as procedure P (X : Der_Base).
7255 -- subtype Der is Der_Base (2);
7256 -- procedure P (X : Der);
7257 -- -- The overriding of P (X : Der_Base) is illegal since we
7258 -- -- have a parameter conformance problem.
7260 -- To get around this problem, after having semantically processed Der_Base
7261 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7262 -- Discriminant_Constraint from Der so that when parameter conformance is
7263 -- checked when P is overridden, no semantic errors are flagged.
7265 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7267 -- Regardless of whether we are dealing with a tagged or untagged type
7268 -- we will transform all derived type declarations of the form
7270 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7271 -- type T is new R [with ...];
7273 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7275 -- The reason for such transformation is that it allows us to implement a
7276 -- very clean form of component inheritance as explained below.
7278 -- Note that this transformation is not achieved by direct tree rewriting
7279 -- and manipulation, but rather by redoing the semantic actions that the
7280 -- above transformation will entail. This is done directly in routine
7281 -- Inherit_Components.
7283 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7285 -- In both tagged and untagged derived types, regular non discriminant
7286 -- components are inherited in the derived type from the parent type. In
7287 -- the absence of discriminants component, inheritance is straightforward
7288 -- as components can simply be copied from the parent.
7290 -- If the parent has discriminants, inheriting components constrained with
7291 -- these discriminants requires caution. Consider the following example:
7293 -- type R (D1, D2 : Positive) is [tagged] record
7294 -- S : String (D1 .. D2);
7297 -- type T1 is new R [with null record];
7298 -- type T2 (X : positive) is new R (1, X) [with null record];
7300 -- As explained in 6. above, T1 is rewritten as
7301 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7302 -- which makes the treatment for T1 and T2 identical.
7304 -- What we want when inheriting S, is that references to D1 and D2 in R are
7305 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7306 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7307 -- with either discriminant references in the derived type or expressions.
7308 -- This replacement is achieved as follows: before inheriting R's
7309 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7310 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7311 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7312 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7313 -- by String (1 .. X).
7315 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7317 -- We explain here the rules governing private type extensions relevant to
7318 -- type derivation. These rules are explained on the following example:
7320 -- type D [(...)] is new A [(...)] with private; <-- partial view
7321 -- type D [(...)] is new P [(...)] with null record; <-- full view
7323 -- Type A is called the ancestor subtype of the private extension.
7324 -- Type P is the parent type of the full view of the private extension. It
7325 -- must be A or a type derived from A.
7327 -- The rules concerning the discriminants of private type extensions are
7330 -- o If a private extension inherits known discriminants from the ancestor
7331 -- subtype, then the full view shall also inherit its discriminants from
7332 -- the ancestor subtype and the parent subtype of the full view shall be
7333 -- constrained if and only if the ancestor subtype is constrained.
7335 -- o If a partial view has unknown discriminants, then the full view may
7336 -- define a definite or an indefinite subtype, with or without
7339 -- o If a partial view has neither known nor unknown discriminants, then
7340 -- the full view shall define a definite subtype.
7342 -- o If the ancestor subtype of a private extension has constrained
7343 -- discriminants, then the parent subtype of the full view shall impose a
7344 -- statically matching constraint on those discriminants.
7346 -- This means that only the following forms of private extensions are
7349 -- type D is new A with private; <-- partial view
7350 -- type D is new P with null record; <-- full view
7352 -- If A has no discriminants than P has no discriminants, otherwise P must
7353 -- inherit A's discriminants.
7355 -- type D is new A (...) with private; <-- partial view
7356 -- type D is new P (:::) with null record; <-- full view
7358 -- P must inherit A's discriminants and (...) and (:::) must statically
7361 -- subtype A is R (...);
7362 -- type D is new A with private; <-- partial view
7363 -- type D is new P with null record; <-- full view
7365 -- P must have inherited R's discriminants and must be derived from A or
7366 -- any of its subtypes.
7368 -- type D (..) is new A with private; <-- partial view
7369 -- type D (..) is new P [(:::)] with null record; <-- full view
7371 -- No specific constraints on P's discriminants or constraint (:::).
7372 -- Note that A can be unconstrained, but the parent subtype P must either
7373 -- be constrained or (:::) must be present.
7375 -- type D (..) is new A [(...)] with private; <-- partial view
7376 -- type D (..) is new P [(:::)] with null record; <-- full view
7378 -- P's constraints on A's discriminants must statically match those
7379 -- imposed by (...).
7381 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7383 -- The full view of a private extension is handled exactly as described
7384 -- above. The model chose for the private view of a private extension is
7385 -- the same for what concerns discriminants (i.e. they receive the same
7386 -- treatment as in the tagged case). However, the private view of the
7387 -- private extension always inherits the components of the parent base,
7388 -- without replacing any discriminant reference. Strictly speaking this is
7389 -- incorrect. However, Gigi never uses this view to generate code so this
7390 -- is a purely semantic issue. In theory, a set of transformations similar
7391 -- to those given in 5. and 6. above could be applied to private views of
7392 -- private extensions to have the same model of component inheritance as
7393 -- for non private extensions. However, this is not done because it would
7394 -- further complicate private type processing. Semantically speaking, this
7395 -- leaves us in an uncomfortable situation. As an example consider:
7398 -- type R (D : integer) is tagged record
7399 -- S : String (1 .. D);
7401 -- procedure P (X : R);
7402 -- type T is new R (1) with private;
7404 -- type T is new R (1) with null record;
7407 -- This is transformed into:
7410 -- type R (D : integer) is tagged record
7411 -- S : String (1 .. D);
7413 -- procedure P (X : R);
7414 -- type T is new R (1) with private;
7416 -- type BaseT is new R with null record;
7417 -- subtype T is BaseT (1);
7420 -- (strictly speaking the above is incorrect Ada)
7422 -- From the semantic standpoint the private view of private extension T
7423 -- should be flagged as constrained since one can clearly have
7427 -- in a unit withing Pack. However, when deriving subprograms for the
7428 -- private view of private extension T, T must be seen as unconstrained
7429 -- since T has discriminants (this is a constraint of the current
7430 -- subprogram derivation model). Thus, when processing the private view of
7431 -- a private extension such as T, we first mark T as unconstrained, we
7432 -- process it, we perform program derivation and just before returning from
7433 -- Build_Derived_Record_Type we mark T as constrained.
7435 -- ??? Are there are other uncomfortable cases that we will have to
7438 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7440 -- Types that are derived from a visible record type and have a private
7441 -- extension present other peculiarities. They behave mostly like private
7442 -- types, but if they have primitive operations defined, these will not
7443 -- have the proper signatures for further inheritance, because other
7444 -- primitive operations will use the implicit base that we define for
7445 -- private derivations below. This affect subprogram inheritance (see
7446 -- Derive_Subprograms for details). We also derive the implicit base from
7447 -- the base type of the full view, so that the implicit base is a record
7448 -- type and not another private type, This avoids infinite loops.
7450 procedure Build_Derived_Record_Type
7452 Parent_Type : Entity_Id;
7453 Derived_Type : Entity_Id;
7454 Derive_Subps : Boolean := True)
7456 Discriminant_Specs : constant Boolean :=
7457 Present (Discriminant_Specifications (N));
7458 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7459 Loc : constant Source_Ptr := Sloc (N);
7460 Private_Extension : constant Boolean :=
7461 Nkind (N) = N_Private_Extension_Declaration;
7462 Assoc_List : Elist_Id;
7463 Constraint_Present : Boolean;
7465 Discrim : Entity_Id;
7467 Inherit_Discrims : Boolean := False;
7468 Last_Discrim : Entity_Id;
7469 New_Base : Entity_Id;
7471 New_Discrs : Elist_Id;
7472 New_Indic : Node_Id;
7473 Parent_Base : Entity_Id;
7474 Save_Etype : Entity_Id;
7475 Save_Discr_Constr : Elist_Id;
7476 Save_Next_Entity : Entity_Id;
7479 Discs : Elist_Id := New_Elmt_List;
7480 -- An empty Discs list means that there were no constraints in the
7481 -- subtype indication or that there was an error processing it.
7484 if Ekind (Parent_Type) = E_Record_Type_With_Private
7485 and then Present (Full_View (Parent_Type))
7486 and then Has_Discriminants (Parent_Type)
7488 Parent_Base := Base_Type (Full_View (Parent_Type));
7490 Parent_Base := Base_Type (Parent_Type);
7493 -- AI05-0115 : if this is a derivation from a private type in some
7494 -- other scope that may lead to invisible components for the derived
7495 -- type, mark it accordingly.
7497 if Is_Private_Type (Parent_Type) then
7498 if Scope (Parent_Type) = Scope (Derived_Type) then
7501 elsif In_Open_Scopes (Scope (Parent_Type))
7502 and then In_Private_Part (Scope (Parent_Type))
7507 Set_Has_Private_Ancestor (Derived_Type);
7511 Set_Has_Private_Ancestor
7512 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7515 -- Before we start the previously documented transformations, here is
7516 -- little fix for size and alignment of tagged types. Normally when we
7517 -- derive type D from type P, we copy the size and alignment of P as the
7518 -- default for D, and in the absence of explicit representation clauses
7519 -- for D, the size and alignment are indeed the same as the parent.
7521 -- But this is wrong for tagged types, since fields may be added, and
7522 -- the default size may need to be larger, and the default alignment may
7523 -- need to be larger.
7525 -- We therefore reset the size and alignment fields in the tagged case.
7526 -- Note that the size and alignment will in any case be at least as
7527 -- large as the parent type (since the derived type has a copy of the
7528 -- parent type in the _parent field)
7530 -- The type is also marked as being tagged here, which is needed when
7531 -- processing components with a self-referential anonymous access type
7532 -- in the call to Check_Anonymous_Access_Components below. Note that
7533 -- this flag is also set later on for completeness.
7536 Set_Is_Tagged_Type (Derived_Type);
7537 Init_Size_Align (Derived_Type);
7540 -- STEP 0a: figure out what kind of derived type declaration we have
7542 if Private_Extension then
7544 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7545 Set_Default_SSO (Derived_Type);
7548 Type_Def := Type_Definition (N);
7550 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7551 -- Parent_Base can be a private type or private extension. However,
7552 -- for tagged types with an extension the newly added fields are
7553 -- visible and hence the Derived_Type is always an E_Record_Type.
7554 -- (except that the parent may have its own private fields).
7555 -- For untagged types we preserve the Ekind of the Parent_Base.
7557 if Present (Record_Extension_Part (Type_Def)) then
7558 Set_Ekind (Derived_Type, E_Record_Type);
7559 Set_Default_SSO (Derived_Type);
7561 -- Create internal access types for components with anonymous
7564 if Ada_Version >= Ada_2005 then
7565 Check_Anonymous_Access_Components
7566 (N, Derived_Type, Derived_Type,
7567 Component_List (Record_Extension_Part (Type_Def)));
7571 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7575 -- Indic can either be an N_Identifier if the subtype indication
7576 -- contains no constraint or an N_Subtype_Indication if the subtype
7577 -- indication has a constraint.
7579 Indic := Subtype_Indication (Type_Def);
7580 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7582 -- Check that the type has visible discriminants. The type may be
7583 -- a private type with unknown discriminants whose full view has
7584 -- discriminants which are invisible.
7586 if Constraint_Present then
7587 if not Has_Discriminants (Parent_Base)
7589 (Has_Unknown_Discriminants (Parent_Base)
7590 and then Is_Private_Type (Parent_Base))
7593 ("invalid constraint: type has no discriminant",
7594 Constraint (Indic));
7596 Constraint_Present := False;
7597 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7599 elsif Is_Constrained (Parent_Type) then
7601 ("invalid constraint: parent type is already constrained",
7602 Constraint (Indic));
7604 Constraint_Present := False;
7605 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7609 -- STEP 0b: If needed, apply transformation given in point 5. above
7611 if not Private_Extension
7612 and then Has_Discriminants (Parent_Type)
7613 and then not Discriminant_Specs
7614 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7616 -- First, we must analyze the constraint (see comment in point 5.)
7617 -- The constraint may come from the subtype indication of the full
7620 if Constraint_Present then
7621 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7623 -- If there is no explicit constraint, there might be one that is
7624 -- inherited from a constrained parent type. In that case verify that
7625 -- it conforms to the constraint in the partial view. In perverse
7626 -- cases the parent subtypes of the partial and full view can have
7627 -- different constraints.
7629 elsif Present (Stored_Constraint (Parent_Type)) then
7630 New_Discrs := Stored_Constraint (Parent_Type);
7633 New_Discrs := No_Elist;
7636 if Has_Discriminants (Derived_Type)
7637 and then Has_Private_Declaration (Derived_Type)
7638 and then Present (Discriminant_Constraint (Derived_Type))
7639 and then Present (New_Discrs)
7641 -- Verify that constraints of the full view statically match
7642 -- those given in the partial view.
7648 C1 := First_Elmt (New_Discrs);
7649 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7650 while Present (C1) and then Present (C2) loop
7651 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7653 (Is_OK_Static_Expression (Node (C1))
7654 and then Is_OK_Static_Expression (Node (C2))
7656 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7661 if Constraint_Present then
7663 ("constraint not conformant to previous declaration",
7667 ("constraint of full view is incompatible "
7668 & "with partial view", N);
7678 -- Insert and analyze the declaration for the unconstrained base type
7680 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7683 Make_Full_Type_Declaration (Loc,
7684 Defining_Identifier => New_Base,
7686 Make_Derived_Type_Definition (Loc,
7687 Abstract_Present => Abstract_Present (Type_Def),
7688 Limited_Present => Limited_Present (Type_Def),
7689 Subtype_Indication =>
7690 New_Occurrence_Of (Parent_Base, Loc),
7691 Record_Extension_Part =>
7692 Relocate_Node (Record_Extension_Part (Type_Def)),
7693 Interface_List => Interface_List (Type_Def)));
7695 Set_Parent (New_Decl, Parent (N));
7696 Mark_Rewrite_Insertion (New_Decl);
7697 Insert_Before (N, New_Decl);
7699 -- In the extension case, make sure ancestor is frozen appropriately
7700 -- (see also non-discriminated case below).
7702 if Present (Record_Extension_Part (Type_Def))
7703 or else Is_Interface (Parent_Base)
7705 Freeze_Before (New_Decl, Parent_Type);
7708 -- Note that this call passes False for the Derive_Subps parameter
7709 -- because subprogram derivation is deferred until after creating
7710 -- the subtype (see below).
7713 (New_Decl, Parent_Base, New_Base,
7714 Is_Completion => True, Derive_Subps => False);
7716 -- ??? This needs re-examination to determine whether the
7717 -- above call can simply be replaced by a call to Analyze.
7719 Set_Analyzed (New_Decl);
7721 -- Insert and analyze the declaration for the constrained subtype
7723 if Constraint_Present then
7725 Make_Subtype_Indication (Loc,
7726 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7727 Constraint => Relocate_Node (Constraint (Indic)));
7731 Constr_List : constant List_Id := New_List;
7736 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7737 while Present (C) loop
7740 -- It is safe here to call New_Copy_Tree since
7741 -- Force_Evaluation was called on each constraint in
7742 -- Build_Discriminant_Constraints.
7744 Append (New_Copy_Tree (Expr), To => Constr_List);
7750 Make_Subtype_Indication (Loc,
7751 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7753 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7758 Make_Subtype_Declaration (Loc,
7759 Defining_Identifier => Derived_Type,
7760 Subtype_Indication => New_Indic));
7764 -- Derivation of subprograms must be delayed until the full subtype
7765 -- has been established, to ensure proper overriding of subprograms
7766 -- inherited by full types. If the derivations occurred as part of
7767 -- the call to Build_Derived_Type above, then the check for type
7768 -- conformance would fail because earlier primitive subprograms
7769 -- could still refer to the full type prior the change to the new
7770 -- subtype and hence would not match the new base type created here.
7771 -- Subprograms are not derived, however, when Derive_Subps is False
7772 -- (since otherwise there could be redundant derivations).
7774 if Derive_Subps then
7775 Derive_Subprograms (Parent_Type, Derived_Type);
7778 -- For tagged types the Discriminant_Constraint of the new base itype
7779 -- is inherited from the first subtype so that no subtype conformance
7780 -- problem arise when the first subtype overrides primitive
7781 -- operations inherited by the implicit base type.
7784 Set_Discriminant_Constraint
7785 (New_Base, Discriminant_Constraint (Derived_Type));
7791 -- If we get here Derived_Type will have no discriminants or it will be
7792 -- a discriminated unconstrained base type.
7794 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7798 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7799 -- The declaration of a specific descendant of an interface type
7800 -- freezes the interface type (RM 13.14).
7802 if not Private_Extension or else Is_Interface (Parent_Base) then
7803 Freeze_Before (N, Parent_Type);
7806 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7807 -- cannot be declared at a deeper level than its parent type is
7808 -- removed. The check on derivation within a generic body is also
7809 -- relaxed, but there's a restriction that a derived tagged type
7810 -- cannot be declared in a generic body if it's derived directly
7811 -- or indirectly from a formal type of that generic.
7813 if Ada_Version >= Ada_2005 then
7814 if Present (Enclosing_Generic_Body (Derived_Type)) then
7816 Ancestor_Type : Entity_Id;
7819 -- Check to see if any ancestor of the derived type is a
7822 Ancestor_Type := Parent_Type;
7823 while not Is_Generic_Type (Ancestor_Type)
7824 and then Etype (Ancestor_Type) /= Ancestor_Type
7826 Ancestor_Type := Etype (Ancestor_Type);
7829 -- If the derived type does have a formal type as an
7830 -- ancestor, then it's an error if the derived type is
7831 -- declared within the body of the generic unit that
7832 -- declares the formal type in its generic formal part. It's
7833 -- sufficient to check whether the ancestor type is declared
7834 -- inside the same generic body as the derived type (such as
7835 -- within a nested generic spec), in which case the
7836 -- derivation is legal. If the formal type is declared
7837 -- outside of that generic body, then it's guaranteed that
7838 -- the derived type is declared within the generic body of
7839 -- the generic unit declaring the formal type.
7841 if Is_Generic_Type (Ancestor_Type)
7842 and then Enclosing_Generic_Body (Ancestor_Type) /=
7843 Enclosing_Generic_Body (Derived_Type)
7846 ("parent type of& must not be descendant of formal type"
7847 & " of an enclosing generic body",
7848 Indic, Derived_Type);
7853 elsif Type_Access_Level (Derived_Type) /=
7854 Type_Access_Level (Parent_Type)
7855 and then not Is_Generic_Type (Derived_Type)
7857 if Is_Controlled (Parent_Type) then
7859 ("controlled type must be declared at the library level",
7863 ("type extension at deeper accessibility level than parent",
7869 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7872 and then GB /= Enclosing_Generic_Body (Parent_Base)
7875 ("parent type of& must not be outside generic body"
7877 Indic, Derived_Type);
7883 -- Ada 2005 (AI-251)
7885 if Ada_Version >= Ada_2005 and then Is_Tagged then
7887 -- "The declaration of a specific descendant of an interface type
7888 -- freezes the interface type" (RM 13.14).
7893 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7894 Iface := First (Interface_List (Type_Def));
7895 while Present (Iface) loop
7896 Freeze_Before (N, Etype (Iface));
7903 -- STEP 1b : preliminary cleanup of the full view of private types
7905 -- If the type is already marked as having discriminants, then it's the
7906 -- completion of a private type or private extension and we need to
7907 -- retain the discriminants from the partial view if the current
7908 -- declaration has Discriminant_Specifications so that we can verify
7909 -- conformance. However, we must remove any existing components that
7910 -- were inherited from the parent (and attached in Copy_And_Swap)
7911 -- because the full type inherits all appropriate components anyway, and
7912 -- we do not want the partial view's components interfering.
7914 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7915 Discrim := First_Discriminant (Derived_Type);
7917 Last_Discrim := Discrim;
7918 Next_Discriminant (Discrim);
7919 exit when No (Discrim);
7922 Set_Last_Entity (Derived_Type, Last_Discrim);
7924 -- In all other cases wipe out the list of inherited components (even
7925 -- inherited discriminants), it will be properly rebuilt here.
7928 Set_First_Entity (Derived_Type, Empty);
7929 Set_Last_Entity (Derived_Type, Empty);
7932 -- STEP 1c: Initialize some flags for the Derived_Type
7934 -- The following flags must be initialized here so that
7935 -- Process_Discriminants can check that discriminants of tagged types do
7936 -- not have a default initial value and that access discriminants are
7937 -- only specified for limited records. For completeness, these flags are
7938 -- also initialized along with all the other flags below.
7940 -- AI-419: Limitedness is not inherited from an interface parent, so to
7941 -- be limited in that case the type must be explicitly declared as
7942 -- limited. However, task and protected interfaces are always limited.
7944 if Limited_Present (Type_Def) then
7945 Set_Is_Limited_Record (Derived_Type);
7947 elsif Is_Limited_Record (Parent_Type)
7948 or else (Present (Full_View (Parent_Type))
7949 and then Is_Limited_Record (Full_View (Parent_Type)))
7951 if not Is_Interface (Parent_Type)
7952 or else Is_Synchronized_Interface (Parent_Type)
7953 or else Is_Protected_Interface (Parent_Type)
7954 or else Is_Task_Interface (Parent_Type)
7956 Set_Is_Limited_Record (Derived_Type);
7960 -- STEP 2a: process discriminants of derived type if any
7962 Push_Scope (Derived_Type);
7964 if Discriminant_Specs then
7965 Set_Has_Unknown_Discriminants (Derived_Type, False);
7967 -- The following call initializes fields Has_Discriminants and
7968 -- Discriminant_Constraint, unless we are processing the completion
7969 -- of a private type declaration.
7971 Check_Or_Process_Discriminants (N, Derived_Type);
7973 -- For untagged types, the constraint on the Parent_Type must be
7974 -- present and is used to rename the discriminants.
7976 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7977 Error_Msg_N ("untagged parent must have discriminants", Indic);
7979 elsif not Is_Tagged and then not Constraint_Present then
7981 ("discriminant constraint needed for derived untagged records",
7984 -- Otherwise the parent subtype must be constrained unless we have a
7985 -- private extension.
7987 elsif not Constraint_Present
7988 and then not Private_Extension
7989 and then not Is_Constrained (Parent_Type)
7992 ("unconstrained type not allowed in this context", Indic);
7994 elsif Constraint_Present then
7995 -- The following call sets the field Corresponding_Discriminant
7996 -- for the discriminants in the Derived_Type.
7998 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8000 -- For untagged types all new discriminants must rename
8001 -- discriminants in the parent. For private extensions new
8002 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8004 Discrim := First_Discriminant (Derived_Type);
8005 while Present (Discrim) loop
8007 and then No (Corresponding_Discriminant (Discrim))
8010 ("new discriminants must constrain old ones", Discrim);
8012 elsif Private_Extension
8013 and then Present (Corresponding_Discriminant (Discrim))
8016 ("only static constraints allowed for parent"
8017 & " discriminants in the partial view", Indic);
8021 -- If a new discriminant is used in the constraint, then its
8022 -- subtype must be statically compatible with the parent
8023 -- discriminant's subtype (3.7(15)).
8025 -- However, if the record contains an array constrained by
8026 -- the discriminant but with some different bound, the compiler
8027 -- attemps to create a smaller range for the discriminant type.
8028 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8029 -- the discriminant type is a scalar type, the check must use
8030 -- the original discriminant type in the parent declaration.
8033 Corr_Disc : constant Entity_Id :=
8034 Corresponding_Discriminant (Discrim);
8035 Disc_Type : constant Entity_Id := Etype (Discrim);
8036 Corr_Type : Entity_Id;
8039 if Present (Corr_Disc) then
8040 if Is_Scalar_Type (Disc_Type) then
8042 Entity (Discriminant_Type (Parent (Corr_Disc)));
8044 Corr_Type := Etype (Corr_Disc);
8048 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8051 ("subtype must be compatible "
8052 & "with parent discriminant",
8058 Next_Discriminant (Discrim);
8061 -- Check whether the constraints of the full view statically
8062 -- match those imposed by the parent subtype [7.3(13)].
8064 if Present (Stored_Constraint (Derived_Type)) then
8069 C1 := First_Elmt (Discs);
8070 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8071 while Present (C1) and then Present (C2) loop
8073 Fully_Conformant_Expressions (Node (C1), Node (C2))
8076 ("not conformant with previous declaration",
8087 -- STEP 2b: No new discriminants, inherit discriminants if any
8090 if Private_Extension then
8091 Set_Has_Unknown_Discriminants
8093 Has_Unknown_Discriminants (Parent_Type)
8094 or else Unknown_Discriminants_Present (N));
8096 -- The partial view of the parent may have unknown discriminants,
8097 -- but if the full view has discriminants and the parent type is
8098 -- in scope they must be inherited.
8100 elsif Has_Unknown_Discriminants (Parent_Type)
8102 (not Has_Discriminants (Parent_Type)
8103 or else not In_Open_Scopes (Scope (Parent_Type)))
8105 Set_Has_Unknown_Discriminants (Derived_Type);
8108 if not Has_Unknown_Discriminants (Derived_Type)
8109 and then not Has_Unknown_Discriminants (Parent_Base)
8110 and then Has_Discriminants (Parent_Type)
8112 Inherit_Discrims := True;
8113 Set_Has_Discriminants
8114 (Derived_Type, True);
8115 Set_Discriminant_Constraint
8116 (Derived_Type, Discriminant_Constraint (Parent_Base));
8119 -- The following test is true for private types (remember
8120 -- transformation 5. is not applied to those) and in an error
8123 if Constraint_Present then
8124 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8127 -- For now mark a new derived type as constrained only if it has no
8128 -- discriminants. At the end of Build_Derived_Record_Type we properly
8129 -- set this flag in the case of private extensions. See comments in
8130 -- point 9. just before body of Build_Derived_Record_Type.
8134 not (Inherit_Discrims
8135 or else Has_Unknown_Discriminants (Derived_Type)));
8138 -- STEP 3: initialize fields of derived type
8140 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8141 Set_Stored_Constraint (Derived_Type, No_Elist);
8143 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8144 -- but cannot be interfaces
8146 if not Private_Extension
8147 and then Ekind (Derived_Type) /= E_Private_Type
8148 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8150 if Interface_Present (Type_Def) then
8151 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8154 Set_Interfaces (Derived_Type, No_Elist);
8157 -- Fields inherited from the Parent_Type
8159 Set_Has_Specified_Layout
8160 (Derived_Type, Has_Specified_Layout (Parent_Type));
8161 Set_Is_Limited_Composite
8162 (Derived_Type, Is_Limited_Composite (Parent_Type));
8163 Set_Is_Private_Composite
8164 (Derived_Type, Is_Private_Composite (Parent_Type));
8166 -- Fields inherited from the Parent_Base
8168 Set_Has_Controlled_Component
8169 (Derived_Type, Has_Controlled_Component (Parent_Base));
8170 Set_Has_Non_Standard_Rep
8171 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8172 Set_Has_Primitive_Operations
8173 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8175 -- Fields inherited from the Parent_Base in the non-private case
8177 if Ekind (Derived_Type) = E_Record_Type then
8178 Set_Has_Complex_Representation
8179 (Derived_Type, Has_Complex_Representation (Parent_Base));
8182 -- Fields inherited from the Parent_Base for record types
8184 if Is_Record_Type (Derived_Type) then
8187 Parent_Full : Entity_Id;
8190 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8191 -- Parent_Base can be a private type or private extension. Go
8192 -- to the full view here to get the E_Record_Type specific flags.
8194 if Present (Full_View (Parent_Base)) then
8195 Parent_Full := Full_View (Parent_Base);
8197 Parent_Full := Parent_Base;
8200 Set_OK_To_Reorder_Components
8201 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8205 -- Set fields for private derived types
8207 if Is_Private_Type (Derived_Type) then
8208 Set_Depends_On_Private (Derived_Type, True);
8209 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8211 -- Inherit fields from non private record types. If this is the
8212 -- completion of a derivation from a private type, the parent itself
8213 -- is private, and the attributes come from its full view, which must
8217 if Is_Private_Type (Parent_Base)
8218 and then not Is_Record_Type (Parent_Base)
8220 Set_Component_Alignment
8221 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8223 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8225 Set_Component_Alignment
8226 (Derived_Type, Component_Alignment (Parent_Base));
8228 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8232 -- Set fields for tagged types
8235 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8237 -- All tagged types defined in Ada.Finalization are controlled
8239 if Chars (Scope (Derived_Type)) = Name_Finalization
8240 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8241 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8243 Set_Is_Controlled (Derived_Type);
8245 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8248 -- Minor optimization: there is no need to generate the class-wide
8249 -- entity associated with an underlying record view.
8251 if not Is_Underlying_Record_View (Derived_Type) then
8252 Make_Class_Wide_Type (Derived_Type);
8255 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8257 if Has_Discriminants (Derived_Type)
8258 and then Constraint_Present
8260 Set_Stored_Constraint
8261 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8264 if Ada_Version >= Ada_2005 then
8266 Ifaces_List : Elist_Id;
8269 -- Checks rules 3.9.4 (13/2 and 14/2)
8271 if Comes_From_Source (Derived_Type)
8272 and then not Is_Private_Type (Derived_Type)
8273 and then Is_Interface (Parent_Type)
8274 and then not Is_Interface (Derived_Type)
8276 if Is_Task_Interface (Parent_Type) then
8278 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8281 elsif Is_Protected_Interface (Parent_Type) then
8283 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8288 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8290 Check_Interfaces (N, Type_Def);
8292 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8293 -- not already in the parents.
8297 Ifaces_List => Ifaces_List,
8298 Exclude_Parents => True);
8300 Set_Interfaces (Derived_Type, Ifaces_List);
8302 -- If the derived type is the anonymous type created for
8303 -- a declaration whose parent has a constraint, propagate
8304 -- the interface list to the source type. This must be done
8305 -- prior to the completion of the analysis of the source type
8306 -- because the components in the extension may contain current
8307 -- instances whose legality depends on some ancestor.
8309 if Is_Itype (Derived_Type) then
8311 Def : constant Node_Id :=
8312 Associated_Node_For_Itype (Derived_Type);
8315 and then Nkind (Def) = N_Full_Type_Declaration
8318 (Defining_Identifier (Def), Ifaces_List);
8326 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8327 Set_Has_Non_Standard_Rep
8328 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8331 -- STEP 4: Inherit components from the parent base and constrain them.
8332 -- Apply the second transformation described in point 6. above.
8334 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8335 or else not Has_Discriminants (Parent_Type)
8336 or else not Is_Constrained (Parent_Type)
8340 Constrs := Discriminant_Constraint (Parent_Type);
8345 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8347 -- STEP 5a: Copy the parent record declaration for untagged types
8349 if not Is_Tagged then
8351 -- Discriminant_Constraint (Derived_Type) has been properly
8352 -- constructed. Save it and temporarily set it to Empty because we
8353 -- do not want the call to New_Copy_Tree below to mess this list.
8355 if Has_Discriminants (Derived_Type) then
8356 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8357 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8359 Save_Discr_Constr := No_Elist;
8362 -- Save the Etype field of Derived_Type. It is correctly set now,
8363 -- but the call to New_Copy tree may remap it to point to itself,
8364 -- which is not what we want. Ditto for the Next_Entity field.
8366 Save_Etype := Etype (Derived_Type);
8367 Save_Next_Entity := Next_Entity (Derived_Type);
8369 -- Assoc_List maps all stored discriminants in the Parent_Base to
8370 -- stored discriminants in the Derived_Type. It is fundamental that
8371 -- no types or itypes with discriminants other than the stored
8372 -- discriminants appear in the entities declared inside
8373 -- Derived_Type, since the back end cannot deal with it.
8377 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8379 -- Restore the fields saved prior to the New_Copy_Tree call
8380 -- and compute the stored constraint.
8382 Set_Etype (Derived_Type, Save_Etype);
8383 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8385 if Has_Discriminants (Derived_Type) then
8386 Set_Discriminant_Constraint
8387 (Derived_Type, Save_Discr_Constr);
8388 Set_Stored_Constraint
8389 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8390 Replace_Components (Derived_Type, New_Decl);
8391 Set_Has_Implicit_Dereference
8392 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8395 -- Insert the new derived type declaration
8397 Rewrite (N, New_Decl);
8399 -- STEP 5b: Complete the processing for record extensions in generics
8401 -- There is no completion for record extensions declared in the
8402 -- parameter part of a generic, so we need to complete processing for
8403 -- these generic record extensions here. The Record_Type_Definition call
8404 -- will change the Ekind of the components from E_Void to E_Component.
8406 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8407 Record_Type_Definition (Empty, Derived_Type);
8409 -- STEP 5c: Process the record extension for non private tagged types
8411 elsif not Private_Extension then
8413 -- Add the _parent field in the derived type. In ASIS mode there is
8414 -- not enough semantic information for full expansion, but set the
8415 -- parent subtype to allow resolution of selected components in
8419 Set_Parent_Subtype (Derived_Type, Parent_Type);
8421 Expand_Record_Extension (Derived_Type, Type_Def);
8424 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8425 -- implemented interfaces if we are in expansion mode
8428 and then Has_Interfaces (Derived_Type)
8430 Add_Interface_Tag_Components (N, Derived_Type);
8433 -- Analyze the record extension
8435 Record_Type_Definition
8436 (Record_Extension_Part (Type_Def), Derived_Type);
8441 -- Nothing else to do if there is an error in the derivation.
8442 -- An unusual case: the full view may be derived from a type in an
8443 -- instance, when the partial view was used illegally as an actual
8444 -- in that instance, leading to a circular definition.
8446 if Etype (Derived_Type) = Any_Type
8447 or else Etype (Parent_Type) = Derived_Type
8452 -- Set delayed freeze and then derive subprograms, we need to do
8453 -- this in this order so that derived subprograms inherit the
8454 -- derived freeze if necessary.
8456 Set_Has_Delayed_Freeze (Derived_Type);
8458 if Derive_Subps then
8459 Derive_Subprograms (Parent_Type, Derived_Type);
8462 -- If we have a private extension which defines a constrained derived
8463 -- type mark as constrained here after we have derived subprograms. See
8464 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8466 if Private_Extension and then Inherit_Discrims then
8467 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8468 Set_Is_Constrained (Derived_Type, True);
8469 Set_Discriminant_Constraint (Derived_Type, Discs);
8471 elsif Is_Constrained (Parent_Type) then
8473 (Derived_Type, True);
8474 Set_Discriminant_Constraint
8475 (Derived_Type, Discriminant_Constraint (Parent_Type));
8479 -- Update the class-wide type, which shares the now-completed entity
8480 -- list with its specific type. In case of underlying record views,
8481 -- we do not generate the corresponding class wide entity.
8484 and then not Is_Underlying_Record_View (Derived_Type)
8487 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8489 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8492 Check_Function_Writable_Actuals (N);
8493 end Build_Derived_Record_Type;
8495 ------------------------
8496 -- Build_Derived_Type --
8497 ------------------------
8499 procedure Build_Derived_Type
8501 Parent_Type : Entity_Id;
8502 Derived_Type : Entity_Id;
8503 Is_Completion : Boolean;
8504 Derive_Subps : Boolean := True)
8506 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8509 -- Set common attributes
8511 Set_Scope (Derived_Type, Current_Scope);
8513 Set_Etype (Derived_Type, Parent_Base);
8514 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8515 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8516 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8518 Set_Size_Info (Derived_Type, Parent_Type);
8519 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8520 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8521 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8523 -- If the parent has primitive routines, set the derived type link
8525 if Has_Primitive_Operations (Parent_Type) then
8526 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8529 -- If the parent type is a private subtype, the convention on the base
8530 -- type may be set in the private part, and not propagated to the
8531 -- subtype until later, so we obtain the convention from the base type.
8533 Set_Convention (Derived_Type, Convention (Parent_Base));
8535 -- Set SSO default for record or array type
8537 if (Is_Array_Type (Derived_Type)
8538 or else Is_Record_Type (Derived_Type))
8539 and then Is_Base_Type (Derived_Type)
8541 Set_Default_SSO (Derived_Type);
8544 -- Propagate invariant information. The new type has invariants if
8545 -- they are inherited from the parent type, and these invariants can
8546 -- be further inherited, so both flags are set.
8548 -- We similarly inherit predicates
8550 if Has_Predicates (Parent_Type) then
8551 Set_Has_Predicates (Derived_Type);
8554 -- The derived type inherits the representation clauses of the parent.
8555 -- However, for a private type that is completed by a derivation, there
8556 -- may be operation attributes that have been specified already (stream
8557 -- attributes and External_Tag) and those must be provided. Finally,
8558 -- if the partial view is a private extension, the representation items
8559 -- of the parent have been inherited already, and should not be chained
8560 -- twice to the derived type.
8562 if Is_Tagged_Type (Parent_Type)
8563 and then Present (First_Rep_Item (Derived_Type))
8565 -- The existing items are either operational items or items inherited
8566 -- from a private extension declaration.
8570 -- Used to iterate over representation items of the derived type
8573 -- Last representation item of the (non-empty) representation
8574 -- item list of the derived type.
8576 Found : Boolean := False;
8579 Rep := First_Rep_Item (Derived_Type);
8581 while Present (Rep) loop
8582 if Rep = First_Rep_Item (Parent_Type) then
8587 Rep := Next_Rep_Item (Rep);
8589 if Present (Rep) then
8595 -- Here if we either encountered the parent type's first rep
8596 -- item on the derived type's rep item list (in which case
8597 -- Found is True, and we have nothing else to do), or if we
8598 -- reached the last rep item of the derived type, which is
8599 -- Last_Rep, in which case we further chain the parent type's
8600 -- rep items to those of the derived type.
8603 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8608 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8611 -- If the parent type has delayed rep aspects, then mark the derived
8612 -- type as possibly inheriting a delayed rep aspect.
8614 if Has_Delayed_Rep_Aspects (Parent_Type) then
8615 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8618 -- Type dependent processing
8620 case Ekind (Parent_Type) is
8621 when Numeric_Kind =>
8622 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8625 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8629 | Class_Wide_Kind =>
8630 Build_Derived_Record_Type
8631 (N, Parent_Type, Derived_Type, Derive_Subps);
8634 when Enumeration_Kind =>
8635 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8638 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8640 when Incomplete_Or_Private_Kind =>
8641 Build_Derived_Private_Type
8642 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8644 -- For discriminated types, the derivation includes deriving
8645 -- primitive operations. For others it is done below.
8647 if Is_Tagged_Type (Parent_Type)
8648 or else Has_Discriminants (Parent_Type)
8649 or else (Present (Full_View (Parent_Type))
8650 and then Has_Discriminants (Full_View (Parent_Type)))
8655 when Concurrent_Kind =>
8656 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8659 raise Program_Error;
8662 -- Nothing more to do if some error occurred
8664 if Etype (Derived_Type) = Any_Type then
8668 -- Set delayed freeze and then derive subprograms, we need to do this
8669 -- in this order so that derived subprograms inherit the derived freeze
8672 Set_Has_Delayed_Freeze (Derived_Type);
8674 if Derive_Subps then
8675 Derive_Subprograms (Parent_Type, Derived_Type);
8678 Set_Has_Primitive_Operations
8679 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8680 end Build_Derived_Type;
8682 -----------------------
8683 -- Build_Discriminal --
8684 -----------------------
8686 procedure Build_Discriminal (Discrim : Entity_Id) is
8687 D_Minal : Entity_Id;
8688 CR_Disc : Entity_Id;
8691 -- A discriminal has the same name as the discriminant
8693 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8695 Set_Ekind (D_Minal, E_In_Parameter);
8696 Set_Mechanism (D_Minal, Default_Mechanism);
8697 Set_Etype (D_Minal, Etype (Discrim));
8698 Set_Scope (D_Minal, Current_Scope);
8700 Set_Discriminal (Discrim, D_Minal);
8701 Set_Discriminal_Link (D_Minal, Discrim);
8703 -- For task types, build at once the discriminants of the corresponding
8704 -- record, which are needed if discriminants are used in entry defaults
8705 -- and in family bounds.
8707 if Is_Concurrent_Type (Current_Scope)
8708 or else Is_Limited_Type (Current_Scope)
8710 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8712 Set_Ekind (CR_Disc, E_In_Parameter);
8713 Set_Mechanism (CR_Disc, Default_Mechanism);
8714 Set_Etype (CR_Disc, Etype (Discrim));
8715 Set_Scope (CR_Disc, Current_Scope);
8716 Set_Discriminal_Link (CR_Disc, Discrim);
8717 Set_CR_Discriminant (Discrim, CR_Disc);
8719 end Build_Discriminal;
8721 ------------------------------------
8722 -- Build_Discriminant_Constraints --
8723 ------------------------------------
8725 function Build_Discriminant_Constraints
8728 Derived_Def : Boolean := False) return Elist_Id
8730 C : constant Node_Id := Constraint (Def);
8731 Nb_Discr : constant Nat := Number_Discriminants (T);
8733 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8734 -- Saves the expression corresponding to a given discriminant in T
8736 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8737 -- Return the Position number within array Discr_Expr of a discriminant
8738 -- D within the discriminant list of the discriminated type T.
8740 procedure Process_Discriminant_Expression
8743 -- If this is a discriminant constraint on a partial view, do not
8744 -- generate an overflow check on the discriminant expression. The check
8745 -- will be generated when constraining the full view. Otherwise the
8746 -- backend creates duplicate symbols for the temporaries corresponding
8747 -- to the expressions to be checked, causing spurious assembler errors.
8753 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8757 Disc := First_Discriminant (T);
8758 for J in Discr_Expr'Range loop
8763 Next_Discriminant (Disc);
8766 -- Note: Since this function is called on discriminants that are
8767 -- known to belong to the discriminated type, falling through the
8768 -- loop with no match signals an internal compiler error.
8770 raise Program_Error;
8773 -------------------------------------
8774 -- Process_Discriminant_Expression --
8775 -------------------------------------
8777 procedure Process_Discriminant_Expression
8781 BDT : constant Entity_Id := Base_Type (Etype (D));
8784 -- If this is a discriminant constraint on a partial view, do
8785 -- not generate an overflow on the discriminant expression. The
8786 -- check will be generated when constraining the full view.
8788 if Is_Private_Type (T)
8789 and then Present (Full_View (T))
8791 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
8793 Analyze_And_Resolve (Expr, BDT);
8795 end Process_Discriminant_Expression;
8797 -- Declarations local to Build_Discriminant_Constraints
8801 Elist : constant Elist_Id := New_Elmt_List;
8809 Discrim_Present : Boolean := False;
8811 -- Start of processing for Build_Discriminant_Constraints
8814 -- The following loop will process positional associations only.
8815 -- For a positional association, the (single) discriminant is
8816 -- implicitly specified by position, in textual order (RM 3.7.2).
8818 Discr := First_Discriminant (T);
8819 Constr := First (Constraints (C));
8820 for D in Discr_Expr'Range loop
8821 exit when Nkind (Constr) = N_Discriminant_Association;
8824 Error_Msg_N ("too few discriminants given in constraint", C);
8825 return New_Elmt_List;
8827 elsif Nkind (Constr) = N_Range
8828 or else (Nkind (Constr) = N_Attribute_Reference
8830 Attribute_Name (Constr) = Name_Range)
8833 ("a range is not a valid discriminant constraint", Constr);
8834 Discr_Expr (D) := Error;
8837 Process_Discriminant_Expression (Constr, Discr);
8838 Discr_Expr (D) := Constr;
8841 Next_Discriminant (Discr);
8845 if No (Discr) and then Present (Constr) then
8846 Error_Msg_N ("too many discriminants given in constraint", Constr);
8847 return New_Elmt_List;
8850 -- Named associations can be given in any order, but if both positional
8851 -- and named associations are used in the same discriminant constraint,
8852 -- then positional associations must occur first, at their normal
8853 -- position. Hence once a named association is used, the rest of the
8854 -- discriminant constraint must use only named associations.
8856 while Present (Constr) loop
8858 -- Positional association forbidden after a named association
8860 if Nkind (Constr) /= N_Discriminant_Association then
8861 Error_Msg_N ("positional association follows named one", Constr);
8862 return New_Elmt_List;
8864 -- Otherwise it is a named association
8867 -- E records the type of the discriminants in the named
8868 -- association. All the discriminants specified in the same name
8869 -- association must have the same type.
8873 -- Search the list of discriminants in T to see if the simple name
8874 -- given in the constraint matches any of them.
8876 Id := First (Selector_Names (Constr));
8877 while Present (Id) loop
8880 -- If Original_Discriminant is present, we are processing a
8881 -- generic instantiation and this is an instance node. We need
8882 -- to find the name of the corresponding discriminant in the
8883 -- actual record type T and not the name of the discriminant in
8884 -- the generic formal. Example:
8887 -- type G (D : int) is private;
8889 -- subtype W is G (D => 1);
8891 -- type Rec (X : int) is record ... end record;
8892 -- package Q is new P (G => Rec);
8894 -- At the point of the instantiation, formal type G is Rec
8895 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8896 -- which really looks like "subtype W is Rec (D => 1);" at
8897 -- the point of instantiation, we want to find the discriminant
8898 -- that corresponds to D in Rec, i.e. X.
8900 if Present (Original_Discriminant (Id))
8901 and then In_Instance
8903 Discr := Find_Corresponding_Discriminant (Id, T);
8907 Discr := First_Discriminant (T);
8908 while Present (Discr) loop
8909 if Chars (Discr) = Chars (Id) then
8914 Next_Discriminant (Discr);
8918 Error_Msg_N ("& does not match any discriminant", Id);
8919 return New_Elmt_List;
8921 -- If the parent type is a generic formal, preserve the
8922 -- name of the discriminant for subsequent instances.
8923 -- see comment at the beginning of this if statement.
8925 elsif Is_Generic_Type (Root_Type (T)) then
8926 Set_Original_Discriminant (Id, Discr);
8930 Position := Pos_Of_Discr (T, Discr);
8932 if Present (Discr_Expr (Position)) then
8933 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8936 -- Each discriminant specified in the same named association
8937 -- must be associated with a separate copy of the
8938 -- corresponding expression.
8940 if Present (Next (Id)) then
8941 Expr := New_Copy_Tree (Expression (Constr));
8942 Set_Parent (Expr, Parent (Expression (Constr)));
8944 Expr := Expression (Constr);
8947 Discr_Expr (Position) := Expr;
8948 Process_Discriminant_Expression (Expr, Discr);
8951 -- A discriminant association with more than one discriminant
8952 -- name is only allowed if the named discriminants are all of
8953 -- the same type (RM 3.7.1(8)).
8956 E := Base_Type (Etype (Discr));
8958 elsif Base_Type (Etype (Discr)) /= E then
8960 ("all discriminants in an association " &
8961 "must have the same type", Id);
8971 -- A discriminant constraint must provide exactly one value for each
8972 -- discriminant of the type (RM 3.7.1(8)).
8974 for J in Discr_Expr'Range loop
8975 if No (Discr_Expr (J)) then
8976 Error_Msg_N ("too few discriminants given in constraint", C);
8977 return New_Elmt_List;
8981 -- Determine if there are discriminant expressions in the constraint
8983 for J in Discr_Expr'Range loop
8984 if Denotes_Discriminant
8985 (Discr_Expr (J), Check_Concurrent => True)
8987 Discrim_Present := True;
8991 -- Build an element list consisting of the expressions given in the
8992 -- discriminant constraint and apply the appropriate checks. The list
8993 -- is constructed after resolving any named discriminant associations
8994 -- and therefore the expressions appear in the textual order of the
8997 Discr := First_Discriminant (T);
8998 for J in Discr_Expr'Range loop
8999 if Discr_Expr (J) /= Error then
9000 Append_Elmt (Discr_Expr (J), Elist);
9002 -- If any of the discriminant constraints is given by a
9003 -- discriminant and we are in a derived type declaration we
9004 -- have a discriminant renaming. Establish link between new
9005 -- and old discriminant.
9007 if Denotes_Discriminant (Discr_Expr (J)) then
9009 Set_Corresponding_Discriminant
9010 (Entity (Discr_Expr (J)), Discr);
9013 -- Force the evaluation of non-discriminant expressions.
9014 -- If we have found a discriminant in the constraint 3.4(26)
9015 -- and 3.8(18) demand that no range checks are performed are
9016 -- after evaluation. If the constraint is for a component
9017 -- definition that has a per-object constraint, expressions are
9018 -- evaluated but not checked either. In all other cases perform
9022 if Discrim_Present then
9025 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9027 Has_Per_Object_Constraint
9028 (Defining_Identifier (Parent (Parent (Def))))
9032 elsif Is_Access_Type (Etype (Discr)) then
9033 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9036 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9039 Force_Evaluation (Discr_Expr (J));
9042 -- Check that the designated type of an access discriminant's
9043 -- expression is not a class-wide type unless the discriminant's
9044 -- designated type is also class-wide.
9046 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9047 and then not Is_Class_Wide_Type
9048 (Designated_Type (Etype (Discr)))
9049 and then Etype (Discr_Expr (J)) /= Any_Type
9050 and then Is_Class_Wide_Type
9051 (Designated_Type (Etype (Discr_Expr (J))))
9053 Wrong_Type (Discr_Expr (J), Etype (Discr));
9055 elsif Is_Access_Type (Etype (Discr))
9056 and then not Is_Access_Constant (Etype (Discr))
9057 and then Is_Access_Type (Etype (Discr_Expr (J)))
9058 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9061 ("constraint for discriminant& must be access to variable",
9066 Next_Discriminant (Discr);
9070 end Build_Discriminant_Constraints;
9072 ---------------------------------
9073 -- Build_Discriminated_Subtype --
9074 ---------------------------------
9076 procedure Build_Discriminated_Subtype
9080 Related_Nod : Node_Id;
9081 For_Access : Boolean := False)
9083 Has_Discrs : constant Boolean := Has_Discriminants (T);
9084 Constrained : constant Boolean :=
9086 and then not Is_Empty_Elmt_List (Elist)
9087 and then not Is_Class_Wide_Type (T))
9088 or else Is_Constrained (T);
9091 if Ekind (T) = E_Record_Type then
9093 Set_Ekind (Def_Id, E_Private_Subtype);
9094 Set_Is_For_Access_Subtype (Def_Id, True);
9096 Set_Ekind (Def_Id, E_Record_Subtype);
9099 -- Inherit preelaboration flag from base, for types for which it
9100 -- may have been set: records, private types, protected types.
9102 Set_Known_To_Have_Preelab_Init
9103 (Def_Id, Known_To_Have_Preelab_Init (T));
9105 elsif Ekind (T) = E_Task_Type then
9106 Set_Ekind (Def_Id, E_Task_Subtype);
9108 elsif Ekind (T) = E_Protected_Type then
9109 Set_Ekind (Def_Id, E_Protected_Subtype);
9110 Set_Known_To_Have_Preelab_Init
9111 (Def_Id, Known_To_Have_Preelab_Init (T));
9113 elsif Is_Private_Type (T) then
9114 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9115 Set_Known_To_Have_Preelab_Init
9116 (Def_Id, Known_To_Have_Preelab_Init (T));
9118 -- Private subtypes may have private dependents
9120 Set_Private_Dependents (Def_Id, New_Elmt_List);
9122 elsif Is_Class_Wide_Type (T) then
9123 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9126 -- Incomplete type. Attach subtype to list of dependents, to be
9127 -- completed with full view of parent type, unless is it the
9128 -- designated subtype of a record component within an init_proc.
9129 -- This last case arises for a component of an access type whose
9130 -- designated type is incomplete (e.g. a Taft Amendment type).
9131 -- The designated subtype is within an inner scope, and needs no
9132 -- elaboration, because only the access type is needed in the
9133 -- initialization procedure.
9135 Set_Ekind (Def_Id, Ekind (T));
9137 if For_Access and then Within_Init_Proc then
9140 Append_Elmt (Def_Id, Private_Dependents (T));
9144 Set_Etype (Def_Id, T);
9145 Init_Size_Align (Def_Id);
9146 Set_Has_Discriminants (Def_Id, Has_Discrs);
9147 Set_Is_Constrained (Def_Id, Constrained);
9149 Set_First_Entity (Def_Id, First_Entity (T));
9150 Set_Last_Entity (Def_Id, Last_Entity (T));
9151 Set_Has_Implicit_Dereference
9152 (Def_Id, Has_Implicit_Dereference (T));
9154 -- If the subtype is the completion of a private declaration, there may
9155 -- have been representation clauses for the partial view, and they must
9156 -- be preserved. Build_Derived_Type chains the inherited clauses with
9157 -- the ones appearing on the extension. If this comes from a subtype
9158 -- declaration, all clauses are inherited.
9160 if No (First_Rep_Item (Def_Id)) then
9161 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9164 if Is_Tagged_Type (T) then
9165 Set_Is_Tagged_Type (Def_Id);
9166 Make_Class_Wide_Type (Def_Id);
9169 Set_Stored_Constraint (Def_Id, No_Elist);
9172 Set_Discriminant_Constraint (Def_Id, Elist);
9173 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9176 if Is_Tagged_Type (T) then
9178 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9179 -- concurrent record type (which has the list of primitive
9182 if Ada_Version >= Ada_2005
9183 and then Is_Concurrent_Type (T)
9185 Set_Corresponding_Record_Type (Def_Id,
9186 Corresponding_Record_Type (T));
9188 Set_Direct_Primitive_Operations (Def_Id,
9189 Direct_Primitive_Operations (T));
9192 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9195 -- Subtypes introduced by component declarations do not need to be
9196 -- marked as delayed, and do not get freeze nodes, because the semantics
9197 -- verifies that the parents of the subtypes are frozen before the
9198 -- enclosing record is frozen.
9200 if not Is_Type (Scope (Def_Id)) then
9201 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9203 if Is_Private_Type (T)
9204 and then Present (Full_View (T))
9206 Conditional_Delay (Def_Id, Full_View (T));
9208 Conditional_Delay (Def_Id, T);
9212 if Is_Record_Type (T) then
9213 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9216 and then not Is_Empty_Elmt_List (Elist)
9217 and then not For_Access
9219 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9220 elsif not For_Access then
9221 Set_Cloned_Subtype (Def_Id, T);
9224 end Build_Discriminated_Subtype;
9226 ---------------------------
9227 -- Build_Itype_Reference --
9228 ---------------------------
9230 procedure Build_Itype_Reference
9234 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9237 -- Itype references are only created for use by the back-end
9239 if Inside_A_Generic then
9242 Set_Itype (IR, Ityp);
9243 Insert_After (Nod, IR);
9245 end Build_Itype_Reference;
9247 ------------------------
9248 -- Build_Scalar_Bound --
9249 ------------------------
9251 function Build_Scalar_Bound
9254 Der_T : Entity_Id) return Node_Id
9256 New_Bound : Entity_Id;
9259 -- Note: not clear why this is needed, how can the original bound
9260 -- be unanalyzed at this point? and if it is, what business do we
9261 -- have messing around with it? and why is the base type of the
9262 -- parent type the right type for the resolution. It probably is
9263 -- not. It is OK for the new bound we are creating, but not for
9264 -- the old one??? Still if it never happens, no problem.
9266 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9268 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9269 New_Bound := New_Copy (Bound);
9270 Set_Etype (New_Bound, Der_T);
9271 Set_Analyzed (New_Bound);
9273 elsif Is_Entity_Name (Bound) then
9274 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9276 -- The following is almost certainly wrong. What business do we have
9277 -- relocating a node (Bound) that is presumably still attached to
9278 -- the tree elsewhere???
9281 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9284 Set_Etype (New_Bound, Der_T);
9286 end Build_Scalar_Bound;
9288 --------------------------------
9289 -- Build_Underlying_Full_View --
9290 --------------------------------
9292 procedure Build_Underlying_Full_View
9297 Loc : constant Source_Ptr := Sloc (N);
9298 Subt : constant Entity_Id :=
9299 Make_Defining_Identifier
9300 (Loc, New_External_Name (Chars (Typ), 'S'));
9307 procedure Set_Discriminant_Name (Id : Node_Id);
9308 -- If the derived type has discriminants, they may rename discriminants
9309 -- of the parent. When building the full view of the parent, we need to
9310 -- recover the names of the original discriminants if the constraint is
9311 -- given by named associations.
9313 ---------------------------
9314 -- Set_Discriminant_Name --
9315 ---------------------------
9317 procedure Set_Discriminant_Name (Id : Node_Id) is
9321 Set_Original_Discriminant (Id, Empty);
9323 if Has_Discriminants (Typ) then
9324 Disc := First_Discriminant (Typ);
9325 while Present (Disc) loop
9326 if Chars (Disc) = Chars (Id)
9327 and then Present (Corresponding_Discriminant (Disc))
9329 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9331 Next_Discriminant (Disc);
9334 end Set_Discriminant_Name;
9336 -- Start of processing for Build_Underlying_Full_View
9339 if Nkind (N) = N_Full_Type_Declaration then
9340 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9342 elsif Nkind (N) = N_Subtype_Declaration then
9343 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9345 elsif Nkind (N) = N_Component_Declaration then
9348 (Constraint (Subtype_Indication (Component_Definition (N))));
9351 raise Program_Error;
9354 C := First (Constraints (Constr));
9355 while Present (C) loop
9356 if Nkind (C) = N_Discriminant_Association then
9357 Id := First (Selector_Names (C));
9358 while Present (Id) loop
9359 Set_Discriminant_Name (Id);
9368 Make_Subtype_Declaration (Loc,
9369 Defining_Identifier => Subt,
9370 Subtype_Indication =>
9371 Make_Subtype_Indication (Loc,
9372 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9373 Constraint => New_Copy_Tree (Constr)));
9375 -- If this is a component subtype for an outer itype, it is not
9376 -- a list member, so simply set the parent link for analysis: if
9377 -- the enclosing type does not need to be in a declarative list,
9378 -- neither do the components.
9380 if Is_List_Member (N)
9381 and then Nkind (N) /= N_Component_Declaration
9383 Insert_Before (N, Indic);
9385 Set_Parent (Indic, Parent (N));
9389 Set_Underlying_Full_View (Typ, Full_View (Subt));
9390 end Build_Underlying_Full_View;
9392 -------------------------------
9393 -- Check_Abstract_Overriding --
9394 -------------------------------
9396 procedure Check_Abstract_Overriding (T : Entity_Id) is
9397 Alias_Subp : Entity_Id;
9403 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9404 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9405 -- which has pragma Implemented already set. Check whether Subp's entity
9406 -- kind conforms to the implementation kind of the overridden routine.
9408 procedure Check_Pragma_Implemented
9410 Iface_Subp : Entity_Id);
9411 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9412 -- Iface_Subp and both entities have pragma Implemented already set on
9413 -- them. Check whether the two implementation kinds are conforming.
9415 procedure Inherit_Pragma_Implemented
9417 Iface_Subp : Entity_Id);
9418 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9419 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9420 -- Propagate the implementation kind of Iface_Subp to Subp.
9422 ------------------------------
9423 -- Check_Pragma_Implemented --
9424 ------------------------------
9426 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9427 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9428 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9429 Subp_Alias : constant Entity_Id := Alias (Subp);
9430 Contr_Typ : Entity_Id;
9431 Impl_Subp : Entity_Id;
9434 -- Subp must have an alias since it is a hidden entity used to link
9435 -- an interface subprogram to its overriding counterpart.
9437 pragma Assert (Present (Subp_Alias));
9439 -- Handle aliases to synchronized wrappers
9441 Impl_Subp := Subp_Alias;
9443 if Is_Primitive_Wrapper (Impl_Subp) then
9444 Impl_Subp := Wrapped_Entity (Impl_Subp);
9447 -- Extract the type of the controlling formal
9449 Contr_Typ := Etype (First_Formal (Subp_Alias));
9451 if Is_Concurrent_Record_Type (Contr_Typ) then
9452 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9455 -- An interface subprogram whose implementation kind is By_Entry must
9456 -- be implemented by an entry.
9458 if Impl_Kind = Name_By_Entry
9459 and then Ekind (Impl_Subp) /= E_Entry
9461 Error_Msg_Node_2 := Iface_Alias;
9463 ("type & must implement abstract subprogram & with an entry",
9464 Subp_Alias, Contr_Typ);
9466 elsif Impl_Kind = Name_By_Protected_Procedure then
9468 -- An interface subprogram whose implementation kind is By_
9469 -- Protected_Procedure cannot be implemented by a primitive
9470 -- procedure of a task type.
9472 if Ekind (Contr_Typ) /= E_Protected_Type then
9473 Error_Msg_Node_2 := Contr_Typ;
9475 ("interface subprogram & cannot be implemented by a " &
9476 "primitive procedure of task type &", Subp_Alias,
9479 -- An interface subprogram whose implementation kind is By_
9480 -- Protected_Procedure must be implemented by a procedure.
9482 elsif Ekind (Impl_Subp) /= E_Procedure then
9483 Error_Msg_Node_2 := Iface_Alias;
9485 ("type & must implement abstract subprogram & with a " &
9486 "procedure", Subp_Alias, Contr_Typ);
9488 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9489 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9491 Error_Msg_Name_1 := Impl_Kind;
9493 ("overriding operation& must have synchronization%",
9497 -- If primitive has Optional synchronization, overriding operation
9498 -- must match if it has an explicit synchronization..
9500 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9501 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9503 Error_Msg_Name_1 := Impl_Kind;
9505 ("overriding operation& must have syncrhonization%",
9508 end Check_Pragma_Implemented;
9510 ------------------------------
9511 -- Check_Pragma_Implemented --
9512 ------------------------------
9514 procedure Check_Pragma_Implemented
9516 Iface_Subp : Entity_Id)
9518 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9519 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9522 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9523 -- and overriding subprogram are different. In general this is an
9524 -- error except when the implementation kind of the overridden
9525 -- subprograms is By_Any or Optional.
9527 if Iface_Kind /= Subp_Kind
9528 and then Iface_Kind /= Name_By_Any
9529 and then Iface_Kind /= Name_Optional
9531 if Iface_Kind = Name_By_Entry then
9533 ("incompatible implementation kind, overridden subprogram " &
9534 "is marked By_Entry", Subp);
9537 ("incompatible implementation kind, overridden subprogram " &
9538 "is marked By_Protected_Procedure", Subp);
9541 end Check_Pragma_Implemented;
9543 --------------------------------
9544 -- Inherit_Pragma_Implemented --
9545 --------------------------------
9547 procedure Inherit_Pragma_Implemented
9549 Iface_Subp : Entity_Id)
9551 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9552 Loc : constant Source_Ptr := Sloc (Subp);
9553 Impl_Prag : Node_Id;
9556 -- Since the implementation kind is stored as a representation item
9557 -- rather than a flag, create a pragma node.
9561 Chars => Name_Implemented,
9562 Pragma_Argument_Associations => New_List (
9563 Make_Pragma_Argument_Association (Loc,
9564 Expression => New_Occurrence_Of (Subp, Loc)),
9566 Make_Pragma_Argument_Association (Loc,
9567 Expression => Make_Identifier (Loc, Iface_Kind))));
9569 -- The pragma doesn't need to be analyzed because it is internally
9570 -- built. It is safe to directly register it as a rep item since we
9571 -- are only interested in the characters of the implementation kind.
9573 Record_Rep_Item (Subp, Impl_Prag);
9574 end Inherit_Pragma_Implemented;
9576 -- Start of processing for Check_Abstract_Overriding
9579 Op_List := Primitive_Operations (T);
9581 -- Loop to check primitive operations
9583 Elmt := First_Elmt (Op_List);
9584 while Present (Elmt) loop
9585 Subp := Node (Elmt);
9586 Alias_Subp := Alias (Subp);
9588 -- Inherited subprograms are identified by the fact that they do not
9589 -- come from source, and the associated source location is the
9590 -- location of the first subtype of the derived type.
9592 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9593 -- subprograms that "require overriding".
9595 -- Special exception, do not complain about failure to override the
9596 -- stream routines _Input and _Output, as well as the primitive
9597 -- operations used in dispatching selects since we always provide
9598 -- automatic overridings for these subprograms.
9600 -- Also ignore this rule for convention CIL since .NET libraries
9601 -- do bizarre things with interfaces???
9603 -- The partial view of T may have been a private extension, for
9604 -- which inherited functions dispatching on result are abstract.
9605 -- If the full view is a null extension, there is no need for
9606 -- overriding in Ada 2005, but wrappers need to be built for them
9607 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9609 if Is_Null_Extension (T)
9610 and then Has_Controlling_Result (Subp)
9611 and then Ada_Version >= Ada_2005
9612 and then Present (Alias_Subp)
9613 and then not Comes_From_Source (Subp)
9614 and then not Is_Abstract_Subprogram (Alias_Subp)
9615 and then not Is_Access_Type (Etype (Subp))
9619 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9620 -- processing because this check is done with the aliased
9623 elsif Present (Interface_Alias (Subp)) then
9626 elsif (Is_Abstract_Subprogram (Subp)
9627 or else Requires_Overriding (Subp)
9629 (Has_Controlling_Result (Subp)
9630 and then Present (Alias_Subp)
9631 and then not Comes_From_Source (Subp)
9632 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9633 and then not Is_TSS (Subp, TSS_Stream_Input)
9634 and then not Is_TSS (Subp, TSS_Stream_Output)
9635 and then not Is_Abstract_Type (T)
9636 and then Convention (T) /= Convention_CIL
9637 and then not Is_Predefined_Interface_Primitive (Subp)
9639 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9640 -- with abstract interface types because the check will be done
9641 -- with the aliased entity (otherwise we generate a duplicated
9644 and then not Present (Interface_Alias (Subp))
9646 if Present (Alias_Subp) then
9648 -- Only perform the check for a derived subprogram when the
9649 -- type has an explicit record extension. This avoids incorrect
9650 -- flagging of abstract subprograms for the case of a type
9651 -- without an extension that is derived from a formal type
9652 -- with a tagged actual (can occur within a private part).
9654 -- Ada 2005 (AI-391): In the case of an inherited function with
9655 -- a controlling result of the type, the rule does not apply if
9656 -- the type is a null extension (unless the parent function
9657 -- itself is abstract, in which case the function must still be
9658 -- be overridden). The expander will generate an overriding
9659 -- wrapper function calling the parent subprogram (see
9660 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9662 Type_Def := Type_Definition (Parent (T));
9664 if Nkind (Type_Def) = N_Derived_Type_Definition
9665 and then Present (Record_Extension_Part (Type_Def))
9667 (Ada_Version < Ada_2005
9668 or else not Is_Null_Extension (T)
9669 or else Ekind (Subp) = E_Procedure
9670 or else not Has_Controlling_Result (Subp)
9671 or else Is_Abstract_Subprogram (Alias_Subp)
9672 or else Requires_Overriding (Subp)
9673 or else Is_Access_Type (Etype (Subp)))
9675 -- Avoid reporting error in case of abstract predefined
9676 -- primitive inherited from interface type because the
9677 -- body of internally generated predefined primitives
9678 -- of tagged types are generated later by Freeze_Type
9680 if Is_Interface (Root_Type (T))
9681 and then Is_Abstract_Subprogram (Subp)
9682 and then Is_Predefined_Dispatching_Operation (Subp)
9683 and then not Comes_From_Source (Ultimate_Alias (Subp))
9689 ("type must be declared abstract or & overridden",
9692 -- Traverse the whole chain of aliased subprograms to
9693 -- complete the error notification. This is especially
9694 -- useful for traceability of the chain of entities when
9695 -- the subprogram corresponds with an interface
9696 -- subprogram (which may be defined in another package).
9698 if Present (Alias_Subp) then
9704 while Present (Alias (E)) loop
9706 -- Avoid reporting redundant errors on entities
9707 -- inherited from interfaces
9709 if Sloc (E) /= Sloc (T) then
9710 Error_Msg_Sloc := Sloc (E);
9712 ("\& has been inherited #", T, Subp);
9718 Error_Msg_Sloc := Sloc (E);
9720 -- AI05-0068: report if there is an overriding
9721 -- non-abstract subprogram that is invisible.
9724 and then not Is_Abstract_Subprogram (E)
9727 ("\& subprogram# is not visible",
9732 ("\& has been inherited from subprogram #",
9739 -- Ada 2005 (AI-345): Protected or task type implementing
9740 -- abstract interfaces.
9742 elsif Is_Concurrent_Record_Type (T)
9743 and then Present (Interfaces (T))
9745 -- If an inherited subprogram is implemented by a protected
9746 -- procedure or an entry, then the first parameter of the
9747 -- inherited subprogram shall be of mode OUT or IN OUT, or
9748 -- an access-to-variable parameter (RM 9.4(11.9/3))
9750 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
9751 and then Ekind (First_Formal (Subp)) = E_In_Parameter
9752 and then Ekind (Subp) /= E_Function
9753 and then not Is_Predefined_Dispatching_Operation (Subp)
9755 Error_Msg_PT (T, Subp);
9757 -- Some other kind of overriding failure
9761 ("interface subprogram & must be overridden",
9764 -- Examine primitive operations of synchronized type,
9765 -- to find homonyms that have the wrong profile.
9772 First_Entity (Corresponding_Concurrent_Type (T));
9773 while Present (Prim) loop
9774 if Chars (Prim) = Chars (Subp) then
9776 ("profile is not type conformant with "
9777 & "prefixed view profile of "
9778 & "inherited operation&", Prim, Subp);
9788 Error_Msg_Node_2 := T;
9790 ("abstract subprogram& not allowed for type&", Subp);
9792 -- Also post unconditional warning on the type (unconditional
9793 -- so that if there are more than one of these cases, we get
9794 -- them all, and not just the first one).
9796 Error_Msg_Node_2 := Subp;
9797 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9801 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
9803 -- Subp is an expander-generated procedure which maps an interface
9804 -- alias to a protected wrapper. The interface alias is flagged by
9805 -- pragma Implemented. Ensure that Subp is a procedure when the
9806 -- implementation kind is By_Protected_Procedure or an entry when
9809 if Ada_Version >= Ada_2012
9810 and then Is_Hidden (Subp)
9811 and then Present (Interface_Alias (Subp))
9812 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9814 Check_Pragma_Implemented (Subp);
9817 -- Subp is an interface primitive which overrides another interface
9818 -- primitive marked with pragma Implemented.
9820 if Ada_Version >= Ada_2012
9821 and then Present (Overridden_Operation (Subp))
9822 and then Has_Rep_Pragma
9823 (Overridden_Operation (Subp), Name_Implemented)
9825 -- If the overriding routine is also marked by Implemented, check
9826 -- that the two implementation kinds are conforming.
9828 if Has_Rep_Pragma (Subp, Name_Implemented) then
9829 Check_Pragma_Implemented
9831 Iface_Subp => Overridden_Operation (Subp));
9833 -- Otherwise the overriding routine inherits the implementation
9834 -- kind from the overridden subprogram.
9837 Inherit_Pragma_Implemented
9839 Iface_Subp => Overridden_Operation (Subp));
9843 -- If the operation is a wrapper for a synchronized primitive, it
9844 -- may be called indirectly through a dispatching select. We assume
9845 -- that it will be referenced elsewhere indirectly, and suppress
9846 -- warnings about an unused entity.
9848 if Is_Primitive_Wrapper (Subp)
9849 and then Present (Wrapped_Entity (Subp))
9851 Set_Referenced (Wrapped_Entity (Subp));
9856 end Check_Abstract_Overriding;
9858 ------------------------------------------------
9859 -- Check_Access_Discriminant_Requires_Limited --
9860 ------------------------------------------------
9862 procedure Check_Access_Discriminant_Requires_Limited
9867 -- A discriminant_specification for an access discriminant shall appear
9868 -- only in the declaration for a task or protected type, or for a type
9869 -- with the reserved word 'limited' in its definition or in one of its
9870 -- ancestors (RM 3.7(10)).
9872 -- AI-0063: The proper condition is that type must be immutably limited,
9873 -- or else be a partial view.
9875 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9876 if Is_Limited_View (Current_Scope)
9878 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9879 and then Limited_Present (Parent (Current_Scope)))
9885 ("access discriminants allowed only for limited types", Loc);
9888 end Check_Access_Discriminant_Requires_Limited;
9890 -----------------------------------
9891 -- Check_Aliased_Component_Types --
9892 -----------------------------------
9894 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9898 -- ??? Also need to check components of record extensions, but not
9899 -- components of protected types (which are always limited).
9901 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9902 -- types to be unconstrained. This is safe because it is illegal to
9903 -- create access subtypes to such types with explicit discriminant
9906 if not Is_Limited_Type (T) then
9907 if Ekind (T) = E_Record_Type then
9908 C := First_Component (T);
9909 while Present (C) loop
9911 and then Has_Discriminants (Etype (C))
9912 and then not Is_Constrained (Etype (C))
9913 and then not In_Instance_Body
9914 and then Ada_Version < Ada_2005
9917 ("aliased component must be constrained (RM 3.6(11))",
9924 elsif Ekind (T) = E_Array_Type then
9925 if Has_Aliased_Components (T)
9926 and then Has_Discriminants (Component_Type (T))
9927 and then not Is_Constrained (Component_Type (T))
9928 and then not In_Instance_Body
9929 and then Ada_Version < Ada_2005
9932 ("aliased component type must be constrained (RM 3.6(11))",
9937 end Check_Aliased_Component_Types;
9939 ----------------------
9940 -- Check_Completion --
9941 ----------------------
9943 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9946 procedure Post_Error;
9947 -- Post error message for lack of completion for entity E
9953 procedure Post_Error is
9955 procedure Missing_Body;
9956 -- Output missing body message
9962 procedure Missing_Body is
9964 -- Spec is in same unit, so we can post on spec
9966 if In_Same_Source_Unit (Body_Id, E) then
9967 Error_Msg_N ("missing body for &", E);
9969 -- Spec is in a separate unit, so we have to post on the body
9972 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9976 -- Start of processing for Post_Error
9979 if not Comes_From_Source (E) then
9981 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9982 -- It may be an anonymous protected type created for a
9983 -- single variable. Post error on variable, if present.
9989 Var := First_Entity (Current_Scope);
9990 while Present (Var) loop
9991 exit when Etype (Var) = E
9992 and then Comes_From_Source (Var);
9997 if Present (Var) then
10004 -- If a generated entity has no completion, then either previous
10005 -- semantic errors have disabled the expansion phase, or else we had
10006 -- missing subunits, or else we are compiling without expansion,
10007 -- or else something is very wrong.
10009 if not Comes_From_Source (E) then
10011 (Serious_Errors_Detected > 0
10012 or else Configurable_Run_Time_Violations > 0
10013 or else Subunits_Missing
10014 or else not Expander_Active);
10017 -- Here for source entity
10020 -- Here if no body to post the error message, so we post the error
10021 -- on the declaration that has no completion. This is not really
10022 -- the right place to post it, think about this later ???
10024 if No (Body_Id) then
10025 if Is_Type (E) then
10027 ("missing full declaration for }", Parent (E), E);
10029 Error_Msg_NE ("missing body for &", Parent (E), E);
10032 -- Package body has no completion for a declaration that appears
10033 -- in the corresponding spec. Post error on the body, with a
10034 -- reference to the non-completed declaration.
10037 Error_Msg_Sloc := Sloc (E);
10039 if Is_Type (E) then
10040 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10042 elsif Is_Overloadable (E)
10043 and then Current_Entity_In_Scope (E) /= E
10045 -- It may be that the completion is mistyped and appears as
10046 -- a distinct overloading of the entity.
10049 Candidate : constant Entity_Id :=
10050 Current_Entity_In_Scope (E);
10051 Decl : constant Node_Id :=
10052 Unit_Declaration_Node (Candidate);
10055 if Is_Overloadable (Candidate)
10056 and then Ekind (Candidate) = Ekind (E)
10057 and then Nkind (Decl) = N_Subprogram_Body
10058 and then Acts_As_Spec (Decl)
10060 Check_Type_Conformant (Candidate, E);
10074 -- Start of processing for Check_Completion
10077 E := First_Entity (Current_Scope);
10078 while Present (E) loop
10079 if Is_Intrinsic_Subprogram (E) then
10082 -- The following situation requires special handling: a child unit
10083 -- that appears in the context clause of the body of its parent:
10085 -- procedure Parent.Child (...);
10087 -- with Parent.Child;
10088 -- package body Parent is
10090 -- Here Parent.Child appears as a local entity, but should not be
10091 -- flagged as requiring completion, because it is a compilation
10094 -- Ignore missing completion for a subprogram that does not come from
10095 -- source (including the _Call primitive operation of RAS types,
10096 -- which has to have the flag Comes_From_Source for other purposes):
10097 -- we assume that the expander will provide the missing completion.
10098 -- In case of previous errors, other expansion actions that provide
10099 -- bodies for null procedures with not be invoked, so inhibit message
10102 -- Note that E_Operator is not in the list that follows, because
10103 -- this kind is reserved for predefined operators, that are
10104 -- intrinsic and do not need completion.
10106 elsif Ekind (E) = E_Function
10107 or else Ekind (E) = E_Procedure
10108 or else Ekind (E) = E_Generic_Function
10109 or else Ekind (E) = E_Generic_Procedure
10111 if Has_Completion (E) then
10114 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10117 elsif Is_Subprogram (E)
10118 and then (not Comes_From_Source (E)
10119 or else Chars (E) = Name_uCall)
10124 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10128 elsif Nkind (Parent (E)) = N_Procedure_Specification
10129 and then Null_Present (Parent (E))
10130 and then Serious_Errors_Detected > 0
10138 elsif Is_Entry (E) then
10139 if not Has_Completion (E) and then
10140 (Ekind (Scope (E)) = E_Protected_Object
10141 or else Ekind (Scope (E)) = E_Protected_Type)
10146 elsif Is_Package_Or_Generic_Package (E) then
10147 if Unit_Requires_Body (E) then
10148 if not Has_Completion (E)
10149 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10155 elsif not Is_Child_Unit (E) then
10156 May_Need_Implicit_Body (E);
10159 -- A formal incomplete type (Ada 2012) does not require a completion;
10160 -- other incomplete type declarations do.
10162 elsif Ekind (E) = E_Incomplete_Type
10163 and then No (Underlying_Type (E))
10164 and then not Is_Generic_Type (E)
10168 elsif (Ekind (E) = E_Task_Type or else
10169 Ekind (E) = E_Protected_Type)
10170 and then not Has_Completion (E)
10174 -- A single task declared in the current scope is a constant, verify
10175 -- that the body of its anonymous type is in the same scope. If the
10176 -- task is defined elsewhere, this may be a renaming declaration for
10177 -- which no completion is needed.
10179 elsif Ekind (E) = E_Constant
10180 and then Ekind (Etype (E)) = E_Task_Type
10181 and then not Has_Completion (Etype (E))
10182 and then Scope (Etype (E)) = Current_Scope
10186 elsif Ekind (E) = E_Protected_Object
10187 and then not Has_Completion (Etype (E))
10191 elsif Ekind (E) = E_Record_Type then
10192 if Is_Tagged_Type (E) then
10193 Check_Abstract_Overriding (E);
10194 Check_Conventions (E);
10197 Check_Aliased_Component_Types (E);
10199 elsif Ekind (E) = E_Array_Type then
10200 Check_Aliased_Component_Types (E);
10206 end Check_Completion;
10208 ------------------------------------
10209 -- Check_CPP_Type_Has_No_Defaults --
10210 ------------------------------------
10212 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10213 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10218 -- Obtain the component list
10220 if Nkind (Tdef) = N_Record_Definition then
10221 Clist := Component_List (Tdef);
10222 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10223 Clist := Component_List (Record_Extension_Part (Tdef));
10226 -- Check all components to ensure no default expressions
10228 if Present (Clist) then
10229 Comp := First (Component_Items (Clist));
10230 while Present (Comp) loop
10231 if Present (Expression (Comp)) then
10233 ("component of imported 'C'P'P type cannot have "
10234 & "default expression", Expression (Comp));
10240 end Check_CPP_Type_Has_No_Defaults;
10242 ----------------------------
10243 -- Check_Delta_Expression --
10244 ----------------------------
10246 procedure Check_Delta_Expression (E : Node_Id) is
10248 if not (Is_Real_Type (Etype (E))) then
10249 Wrong_Type (E, Any_Real);
10251 elsif not Is_OK_Static_Expression (E) then
10252 Flag_Non_Static_Expr
10253 ("non-static expression used for delta value!", E);
10255 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10256 Error_Msg_N ("delta expression must be positive", E);
10262 -- If any of above errors occurred, then replace the incorrect
10263 -- expression by the real 0.1, which should prevent further errors.
10266 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10267 Analyze_And_Resolve (E, Standard_Float);
10268 end Check_Delta_Expression;
10270 -----------------------------
10271 -- Check_Digits_Expression --
10272 -----------------------------
10274 procedure Check_Digits_Expression (E : Node_Id) is
10276 if not (Is_Integer_Type (Etype (E))) then
10277 Wrong_Type (E, Any_Integer);
10279 elsif not Is_OK_Static_Expression (E) then
10280 Flag_Non_Static_Expr
10281 ("non-static expression used for digits value!", E);
10283 elsif Expr_Value (E) <= 0 then
10284 Error_Msg_N ("digits value must be greater than zero", E);
10290 -- If any of above errors occurred, then replace the incorrect
10291 -- expression by the integer 1, which should prevent further errors.
10293 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
10294 Analyze_And_Resolve (E, Standard_Integer);
10296 end Check_Digits_Expression;
10298 --------------------------
10299 -- Check_Initialization --
10300 --------------------------
10302 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
10304 if Is_Limited_Type (T)
10305 and then not In_Instance
10306 and then not In_Inlined_Body
10308 if not OK_For_Limited_Init (T, Exp) then
10310 -- In GNAT mode, this is just a warning, to allow it to be evilly
10311 -- turned off. Otherwise it is a real error.
10315 ("??cannot initialize entities of limited type!", Exp);
10317 elsif Ada_Version < Ada_2005 then
10319 -- The side effect removal machinery may generate illegal Ada
10320 -- code to avoid the usage of access types and 'reference in
10321 -- SPARK mode. Since this is legal code with respect to theorem
10322 -- proving, do not emit the error.
10325 and then Nkind (Exp) = N_Function_Call
10326 and then Nkind (Parent (Exp)) = N_Object_Declaration
10327 and then not Comes_From_Source
10328 (Defining_Identifier (Parent (Exp)))
10334 ("cannot initialize entities of limited type", Exp);
10335 Explain_Limited_Type (T, Exp);
10339 -- Specialize error message according to kind of illegal
10340 -- initial expression.
10342 if Nkind (Exp) = N_Type_Conversion
10343 and then Nkind (Expression (Exp)) = N_Function_Call
10346 ("illegal context for call"
10347 & " to function with limited result", Exp);
10351 ("initialization of limited object requires aggregate "
10352 & "or function call", Exp);
10357 end Check_Initialization;
10359 ----------------------
10360 -- Check_Interfaces --
10361 ----------------------
10363 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
10364 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
10367 Iface_Def : Node_Id;
10368 Iface_Typ : Entity_Id;
10369 Parent_Node : Node_Id;
10371 Is_Task : Boolean := False;
10372 -- Set True if parent type or any progenitor is a task interface
10374 Is_Protected : Boolean := False;
10375 -- Set True if parent type or any progenitor is a protected interface
10377 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
10378 -- Check that a progenitor is compatible with declaration.
10379 -- Error is posted on Error_Node.
10385 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
10386 Iface_Id : constant Entity_Id :=
10387 Defining_Identifier (Parent (Iface_Def));
10388 Type_Def : Node_Id;
10391 if Nkind (N) = N_Private_Extension_Declaration then
10394 Type_Def := Type_Definition (N);
10397 if Is_Task_Interface (Iface_Id) then
10400 elsif Is_Protected_Interface (Iface_Id) then
10401 Is_Protected := True;
10404 if Is_Synchronized_Interface (Iface_Id) then
10406 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
10407 -- extension derived from a synchronized interface must explicitly
10408 -- be declared synchronized, because the full view will be a
10409 -- synchronized type.
10411 if Nkind (N) = N_Private_Extension_Declaration then
10412 if not Synchronized_Present (N) then
10414 ("private extension of& must be explicitly synchronized",
10418 -- However, by 3.9.4(16/2), a full type that is a record extension
10419 -- is never allowed to derive from a synchronized interface (note
10420 -- that interfaces must be excluded from this check, because those
10421 -- are represented by derived type definitions in some cases).
10423 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10424 and then not Interface_Present (Type_Definition (N))
10426 Error_Msg_N ("record extension cannot derive from synchronized"
10427 & " interface", Error_Node);
10431 -- Check that the characteristics of the progenitor are compatible
10432 -- with the explicit qualifier in the declaration.
10433 -- The check only applies to qualifiers that come from source.
10434 -- Limited_Present also appears in the declaration of corresponding
10435 -- records, and the check does not apply to them.
10437 if Limited_Present (Type_Def)
10439 Is_Concurrent_Record_Type (Defining_Identifier (N))
10441 if Is_Limited_Interface (Parent_Type)
10442 and then not Is_Limited_Interface (Iface_Id)
10445 ("progenitor& must be limited interface",
10446 Error_Node, Iface_Id);
10449 (Task_Present (Iface_Def)
10450 or else Protected_Present (Iface_Def)
10451 or else Synchronized_Present (Iface_Def))
10452 and then Nkind (N) /= N_Private_Extension_Declaration
10453 and then not Error_Posted (N)
10456 ("progenitor& must be limited interface",
10457 Error_Node, Iface_Id);
10460 -- Protected interfaces can only inherit from limited, synchronized
10461 -- or protected interfaces.
10463 elsif Nkind (N) = N_Full_Type_Declaration
10464 and then Protected_Present (Type_Def)
10466 if Limited_Present (Iface_Def)
10467 or else Synchronized_Present (Iface_Def)
10468 or else Protected_Present (Iface_Def)
10472 elsif Task_Present (Iface_Def) then
10473 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10474 & " from task interface", Error_Node);
10477 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10478 & " from non-limited interface", Error_Node);
10481 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
10482 -- limited and synchronized.
10484 elsif Synchronized_Present (Type_Def) then
10485 if Limited_Present (Iface_Def)
10486 or else Synchronized_Present (Iface_Def)
10490 elsif Protected_Present (Iface_Def)
10491 and then Nkind (N) /= N_Private_Extension_Declaration
10493 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10494 & " from protected interface", Error_Node);
10496 elsif Task_Present (Iface_Def)
10497 and then Nkind (N) /= N_Private_Extension_Declaration
10499 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10500 & " from task interface", Error_Node);
10502 elsif not Is_Limited_Interface (Iface_Id) then
10503 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10504 & " from non-limited interface", Error_Node);
10507 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
10508 -- synchronized or task interfaces.
10510 elsif Nkind (N) = N_Full_Type_Declaration
10511 and then Task_Present (Type_Def)
10513 if Limited_Present (Iface_Def)
10514 or else Synchronized_Present (Iface_Def)
10515 or else Task_Present (Iface_Def)
10519 elsif Protected_Present (Iface_Def) then
10520 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10521 & " protected interface", Error_Node);
10524 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10525 & " non-limited interface", Error_Node);
10530 -- Start of processing for Check_Interfaces
10533 if Is_Interface (Parent_Type) then
10534 if Is_Task_Interface (Parent_Type) then
10537 elsif Is_Protected_Interface (Parent_Type) then
10538 Is_Protected := True;
10542 if Nkind (N) = N_Private_Extension_Declaration then
10544 -- Check that progenitors are compatible with declaration
10546 Iface := First (Interface_List (Def));
10547 while Present (Iface) loop
10548 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10550 Parent_Node := Parent (Base_Type (Iface_Typ));
10551 Iface_Def := Type_Definition (Parent_Node);
10553 if not Is_Interface (Iface_Typ) then
10554 Diagnose_Interface (Iface, Iface_Typ);
10557 Check_Ifaces (Iface_Def, Iface);
10563 if Is_Task and Is_Protected then
10565 ("type cannot derive from task and protected interface", N);
10571 -- Full type declaration of derived type.
10572 -- Check compatibility with parent if it is interface type
10574 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10575 and then Is_Interface (Parent_Type)
10577 Parent_Node := Parent (Parent_Type);
10579 -- More detailed checks for interface varieties
10582 (Iface_Def => Type_Definition (Parent_Node),
10583 Error_Node => Subtype_Indication (Type_Definition (N)));
10586 Iface := First (Interface_List (Def));
10587 while Present (Iface) loop
10588 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10590 Parent_Node := Parent (Base_Type (Iface_Typ));
10591 Iface_Def := Type_Definition (Parent_Node);
10593 if not Is_Interface (Iface_Typ) then
10594 Diagnose_Interface (Iface, Iface_Typ);
10597 -- "The declaration of a specific descendant of an interface
10598 -- type freezes the interface type" RM 13.14
10600 Freeze_Before (N, Iface_Typ);
10601 Check_Ifaces (Iface_Def, Error_Node => Iface);
10607 if Is_Task and Is_Protected then
10609 ("type cannot derive from task and protected interface", N);
10611 end Check_Interfaces;
10613 ------------------------------------
10614 -- Check_Or_Process_Discriminants --
10615 ------------------------------------
10617 -- If an incomplete or private type declaration was already given for the
10618 -- type, the discriminants may have already been processed if they were
10619 -- present on the incomplete declaration. In this case a full conformance
10620 -- check has been performed in Find_Type_Name, and we then recheck here
10621 -- some properties that can't be checked on the partial view alone.
10622 -- Otherwise we call Process_Discriminants.
10624 procedure Check_Or_Process_Discriminants
10627 Prev : Entity_Id := Empty)
10630 if Has_Discriminants (T) then
10632 -- Discriminants are already set on T if they were already present
10633 -- on the partial view. Make them visible to component declarations.
10637 -- Discriminant on T (full view) referencing expr on partial view
10639 Prev_D : Entity_Id;
10640 -- Entity of corresponding discriminant on partial view
10643 -- Discriminant specification for full view, expression is the
10644 -- syntactic copy on full view (which has been checked for
10645 -- conformance with partial view), only used here to post error
10649 D := First_Discriminant (T);
10650 New_D := First (Discriminant_Specifications (N));
10651 while Present (D) loop
10652 Prev_D := Current_Entity (D);
10653 Set_Current_Entity (D);
10654 Set_Is_Immediately_Visible (D);
10655 Set_Homonym (D, Prev_D);
10657 -- Handle the case where there is an untagged partial view and
10658 -- the full view is tagged: must disallow discriminants with
10659 -- defaults, unless compiling for Ada 2012, which allows a
10660 -- limited tagged type to have defaulted discriminants (see
10661 -- AI05-0214). However, suppress error here if it was already
10662 -- reported on the default expression of the partial view.
10664 if Is_Tagged_Type (T)
10665 and then Present (Expression (Parent (D)))
10666 and then (not Is_Limited_Type (Current_Scope)
10667 or else Ada_Version < Ada_2012)
10668 and then not Error_Posted (Expression (Parent (D)))
10670 if Ada_Version >= Ada_2012 then
10672 ("discriminants of nonlimited tagged type cannot have"
10674 Expression (New_D));
10677 ("discriminants of tagged type cannot have defaults",
10678 Expression (New_D));
10682 -- Ada 2005 (AI-230): Access discriminant allowed in
10683 -- non-limited record types.
10685 if Ada_Version < Ada_2005 then
10687 -- This restriction gets applied to the full type here. It
10688 -- has already been applied earlier to the partial view.
10690 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10693 Next_Discriminant (D);
10698 elsif Present (Discriminant_Specifications (N)) then
10699 Process_Discriminants (N, Prev);
10701 end Check_Or_Process_Discriminants;
10703 ----------------------
10704 -- Check_Real_Bound --
10705 ----------------------
10707 procedure Check_Real_Bound (Bound : Node_Id) is
10709 if not Is_Real_Type (Etype (Bound)) then
10711 ("bound in real type definition must be of real type", Bound);
10713 elsif not Is_OK_Static_Expression (Bound) then
10714 Flag_Non_Static_Expr
10715 ("non-static expression used for real type bound!", Bound);
10722 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10724 Resolve (Bound, Standard_Float);
10725 end Check_Real_Bound;
10727 ------------------------------
10728 -- Complete_Private_Subtype --
10729 ------------------------------
10731 procedure Complete_Private_Subtype
10734 Full_Base : Entity_Id;
10735 Related_Nod : Node_Id)
10737 Save_Next_Entity : Entity_Id;
10738 Save_Homonym : Entity_Id;
10741 -- Set semantic attributes for (implicit) private subtype completion.
10742 -- If the full type has no discriminants, then it is a copy of the full
10743 -- view of the base. Otherwise, it is a subtype of the base with a
10744 -- possible discriminant constraint. Save and restore the original
10745 -- Next_Entity field of full to ensure that the calls to Copy_Node
10746 -- do not corrupt the entity chain.
10748 -- Note that the type of the full view is the same entity as the type of
10749 -- the partial view. In this fashion, the subtype has access to the
10750 -- correct view of the parent.
10752 Save_Next_Entity := Next_Entity (Full);
10753 Save_Homonym := Homonym (Priv);
10755 case Ekind (Full_Base) is
10756 when E_Record_Type |
10762 Copy_Node (Priv, Full);
10764 Set_Has_Discriminants
10765 (Full, Has_Discriminants (Full_Base));
10766 Set_Has_Unknown_Discriminants
10767 (Full, Has_Unknown_Discriminants (Full_Base));
10768 Set_First_Entity (Full, First_Entity (Full_Base));
10769 Set_Last_Entity (Full, Last_Entity (Full_Base));
10771 -- If the underlying base type is constrained, we know that the
10772 -- full view of the subtype is constrained as well (the converse
10773 -- is not necessarily true).
10775 if Is_Constrained (Full_Base) then
10776 Set_Is_Constrained (Full);
10780 Copy_Node (Full_Base, Full);
10782 Set_Chars (Full, Chars (Priv));
10783 Conditional_Delay (Full, Priv);
10784 Set_Sloc (Full, Sloc (Priv));
10787 Set_Next_Entity (Full, Save_Next_Entity);
10788 Set_Homonym (Full, Save_Homonym);
10789 Set_Associated_Node_For_Itype (Full, Related_Nod);
10791 -- Set common attributes for all subtypes: kind, convention, etc.
10793 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10794 Set_Convention (Full, Convention (Full_Base));
10796 -- The Etype of the full view is inconsistent. Gigi needs to see the
10797 -- structural full view, which is what the current scheme gives:
10798 -- the Etype of the full view is the etype of the full base. However,
10799 -- if the full base is a derived type, the full view then looks like
10800 -- a subtype of the parent, not a subtype of the full base. If instead
10803 -- Set_Etype (Full, Full_Base);
10805 -- then we get inconsistencies in the front-end (confusion between
10806 -- views). Several outstanding bugs are related to this ???
10808 Set_Is_First_Subtype (Full, False);
10809 Set_Scope (Full, Scope (Priv));
10810 Set_Size_Info (Full, Full_Base);
10811 Set_RM_Size (Full, RM_Size (Full_Base));
10812 Set_Is_Itype (Full);
10814 -- A subtype of a private-type-without-discriminants, whose full-view
10815 -- has discriminants with default expressions, is not constrained.
10817 if not Has_Discriminants (Priv) then
10818 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10820 if Has_Discriminants (Full_Base) then
10821 Set_Discriminant_Constraint
10822 (Full, Discriminant_Constraint (Full_Base));
10824 -- The partial view may have been indefinite, the full view
10827 Set_Has_Unknown_Discriminants
10828 (Full, Has_Unknown_Discriminants (Full_Base));
10832 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10833 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10835 -- Freeze the private subtype entity if its parent is delayed, and not
10836 -- already frozen. We skip this processing if the type is an anonymous
10837 -- subtype of a record component, or is the corresponding record of a
10838 -- protected type, since ???
10840 if not Is_Type (Scope (Full)) then
10841 Set_Has_Delayed_Freeze (Full,
10842 Has_Delayed_Freeze (Full_Base)
10843 and then (not Is_Frozen (Full_Base)));
10846 Set_Freeze_Node (Full, Empty);
10847 Set_Is_Frozen (Full, False);
10848 Set_Full_View (Priv, Full);
10850 if Has_Discriminants (Full) then
10851 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10852 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10854 if Has_Unknown_Discriminants (Full) then
10855 Set_Discriminant_Constraint (Full, No_Elist);
10859 if Ekind (Full_Base) = E_Record_Type
10860 and then Has_Discriminants (Full_Base)
10861 and then Has_Discriminants (Priv) -- might not, if errors
10862 and then not Has_Unknown_Discriminants (Priv)
10863 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10865 Create_Constrained_Components
10866 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10868 -- If the full base is itself derived from private, build a congruent
10869 -- subtype of its underlying type, for use by the back end. For a
10870 -- constrained record component, the declaration cannot be placed on
10871 -- the component list, but it must nevertheless be built an analyzed, to
10872 -- supply enough information for Gigi to compute the size of component.
10874 elsif Ekind (Full_Base) in Private_Kind
10875 and then Is_Derived_Type (Full_Base)
10876 and then Has_Discriminants (Full_Base)
10877 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10879 if not Is_Itype (Priv)
10881 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10883 Build_Underlying_Full_View
10884 (Parent (Priv), Full, Etype (Full_Base));
10886 elsif Nkind (Related_Nod) = N_Component_Declaration then
10887 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10890 elsif Is_Record_Type (Full_Base) then
10892 -- Show Full is simply a renaming of Full_Base
10894 Set_Cloned_Subtype (Full, Full_Base);
10897 -- It is unsafe to share the bounds of a scalar type, because the Itype
10898 -- is elaborated on demand, and if a bound is non-static then different
10899 -- orders of elaboration in different units will lead to different
10900 -- external symbols.
10902 if Is_Scalar_Type (Full_Base) then
10903 Set_Scalar_Range (Full,
10904 Make_Range (Sloc (Related_Nod),
10906 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10908 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10910 -- This completion inherits the bounds of the full parent, but if
10911 -- the parent is an unconstrained floating point type, so is the
10914 if Is_Floating_Point_Type (Full_Base) then
10915 Set_Includes_Infinities
10916 (Scalar_Range (Full), Has_Infinities (Full_Base));
10920 -- ??? It seems that a lot of fields are missing that should be copied
10921 -- from Full_Base to Full. Here are some that are introduced in a
10922 -- non-disruptive way but a cleanup is necessary.
10924 if Is_Tagged_Type (Full_Base) then
10925 Set_Is_Tagged_Type (Full);
10926 Set_Direct_Primitive_Operations (Full,
10927 Direct_Primitive_Operations (Full_Base));
10929 -- Inherit class_wide type of full_base in case the partial view was
10930 -- not tagged. Otherwise it has already been created when the private
10931 -- subtype was analyzed.
10933 if No (Class_Wide_Type (Full)) then
10934 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10937 -- If this is a subtype of a protected or task type, constrain its
10938 -- corresponding record, unless this is a subtype without constraints,
10939 -- i.e. a simple renaming as with an actual subtype in an instance.
10941 elsif Is_Concurrent_Type (Full_Base) then
10942 if Has_Discriminants (Full)
10943 and then Present (Corresponding_Record_Type (Full_Base))
10945 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10947 Set_Corresponding_Record_Type (Full,
10948 Constrain_Corresponding_Record
10949 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
10952 Set_Corresponding_Record_Type (Full,
10953 Corresponding_Record_Type (Full_Base));
10957 -- Link rep item chain, and also setting of Has_Predicates from private
10958 -- subtype to full subtype, since we will need these on the full subtype
10959 -- to create the predicate function. Note that the full subtype may
10960 -- already have rep items, inherited from the full view of the base
10961 -- type, so we must be sure not to overwrite these entries.
10966 Next_Item : Node_Id;
10969 Item := First_Rep_Item (Full);
10971 -- If no existing rep items on full type, we can just link directly
10972 -- to the list of items on the private type.
10975 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10977 -- Otherwise, search to the end of items currently linked to the full
10978 -- subtype and append the private items to the end. However, if Priv
10979 -- and Full already have the same list of rep items, then the append
10980 -- is not done, as that would create a circularity.
10982 elsif Item /= First_Rep_Item (Priv) then
10986 Next_Item := Next_Rep_Item (Item);
10987 exit when No (Next_Item);
10990 -- If the private view has aspect specifications, the full view
10991 -- inherits them. Since these aspects may already have been
10992 -- attached to the full view during derivation, do not append
10993 -- them if already present.
10995 if Item = First_Rep_Item (Priv) then
11001 -- And link the private type items at the end of the chain
11004 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11009 -- Make sure Has_Predicates is set on full type if it is set on the
11010 -- private type. Note that it may already be set on the full type and
11011 -- if so, we don't want to unset it.
11013 if Has_Predicates (Priv) then
11014 Set_Has_Predicates (Full);
11016 end Complete_Private_Subtype;
11018 ----------------------------
11019 -- Constant_Redeclaration --
11020 ----------------------------
11022 procedure Constant_Redeclaration
11027 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11028 Obj_Def : constant Node_Id := Object_Definition (N);
11031 procedure Check_Possible_Deferred_Completion
11032 (Prev_Id : Entity_Id;
11033 Prev_Obj_Def : Node_Id;
11034 Curr_Obj_Def : Node_Id);
11035 -- Determine whether the two object definitions describe the partial
11036 -- and the full view of a constrained deferred constant. Generate
11037 -- a subtype for the full view and verify that it statically matches
11038 -- the subtype of the partial view.
11040 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11041 -- If deferred constant is an access type initialized with an allocator,
11042 -- check whether there is an illegal recursion in the definition,
11043 -- through a default value of some record subcomponent. This is normally
11044 -- detected when generating init procs, but requires this additional
11045 -- mechanism when expansion is disabled.
11047 ----------------------------------------
11048 -- Check_Possible_Deferred_Completion --
11049 ----------------------------------------
11051 procedure Check_Possible_Deferred_Completion
11052 (Prev_Id : Entity_Id;
11053 Prev_Obj_Def : Node_Id;
11054 Curr_Obj_Def : Node_Id)
11057 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11058 and then Present (Constraint (Prev_Obj_Def))
11059 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11060 and then Present (Constraint (Curr_Obj_Def))
11063 Loc : constant Source_Ptr := Sloc (N);
11064 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11065 Decl : constant Node_Id :=
11066 Make_Subtype_Declaration (Loc,
11067 Defining_Identifier => Def_Id,
11068 Subtype_Indication =>
11069 Relocate_Node (Curr_Obj_Def));
11072 Insert_Before_And_Analyze (N, Decl);
11073 Set_Etype (Id, Def_Id);
11075 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11076 Error_Msg_Sloc := Sloc (Prev_Id);
11077 Error_Msg_N ("subtype does not statically match deferred " &
11078 "declaration#", N);
11082 end Check_Possible_Deferred_Completion;
11084 ---------------------------------
11085 -- Check_Recursive_Declaration --
11086 ---------------------------------
11088 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11092 if Is_Record_Type (Typ) then
11093 Comp := First_Component (Typ);
11094 while Present (Comp) loop
11095 if Comes_From_Source (Comp) then
11096 if Present (Expression (Parent (Comp)))
11097 and then Is_Entity_Name (Expression (Parent (Comp)))
11098 and then Entity (Expression (Parent (Comp))) = Prev
11100 Error_Msg_Sloc := Sloc (Parent (Comp));
11102 ("illegal circularity with declaration for&#",
11106 elsif Is_Record_Type (Etype (Comp)) then
11107 Check_Recursive_Declaration (Etype (Comp));
11111 Next_Component (Comp);
11114 end Check_Recursive_Declaration;
11116 -- Start of processing for Constant_Redeclaration
11119 if Nkind (Parent (Prev)) = N_Object_Declaration then
11120 if Nkind (Object_Definition
11121 (Parent (Prev))) = N_Subtype_Indication
11123 -- Find type of new declaration. The constraints of the two
11124 -- views must match statically, but there is no point in
11125 -- creating an itype for the full view.
11127 if Nkind (Obj_Def) = N_Subtype_Indication then
11128 Find_Type (Subtype_Mark (Obj_Def));
11129 New_T := Entity (Subtype_Mark (Obj_Def));
11132 Find_Type (Obj_Def);
11133 New_T := Entity (Obj_Def);
11139 -- The full view may impose a constraint, even if the partial
11140 -- view does not, so construct the subtype.
11142 New_T := Find_Type_Of_Object (Obj_Def, N);
11147 -- Current declaration is illegal, diagnosed below in Enter_Name
11153 -- If previous full declaration or a renaming declaration exists, or if
11154 -- a homograph is present, let Enter_Name handle it, either with an
11155 -- error or with the removal of an overridden implicit subprogram.
11156 -- The previous one is a full declaration if it has an expression
11157 -- (which in the case of an aggregate is indicated by the Init flag).
11159 if Ekind (Prev) /= E_Constant
11160 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11161 or else Present (Expression (Parent (Prev)))
11162 or else Has_Init_Expression (Parent (Prev))
11163 or else Present (Full_View (Prev))
11167 -- Verify that types of both declarations match, or else that both types
11168 -- are anonymous access types whose designated subtypes statically match
11169 -- (as allowed in Ada 2005 by AI-385).
11171 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11173 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11174 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11175 or else Is_Access_Constant (Etype (New_T)) /=
11176 Is_Access_Constant (Etype (Prev))
11177 or else Can_Never_Be_Null (Etype (New_T)) /=
11178 Can_Never_Be_Null (Etype (Prev))
11179 or else Null_Exclusion_Present (Parent (Prev)) /=
11180 Null_Exclusion_Present (Parent (Id))
11181 or else not Subtypes_Statically_Match
11182 (Designated_Type (Etype (Prev)),
11183 Designated_Type (Etype (New_T))))
11185 Error_Msg_Sloc := Sloc (Prev);
11186 Error_Msg_N ("type does not match declaration#", N);
11187 Set_Full_View (Prev, Id);
11188 Set_Etype (Id, Any_Type);
11191 Null_Exclusion_Present (Parent (Prev))
11192 and then not Null_Exclusion_Present (N)
11194 Error_Msg_Sloc := Sloc (Prev);
11195 Error_Msg_N ("null-exclusion does not match declaration#", N);
11196 Set_Full_View (Prev, Id);
11197 Set_Etype (Id, Any_Type);
11199 -- If so, process the full constant declaration
11202 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11203 -- the deferred declaration is constrained, then the subtype defined
11204 -- by the subtype_indication in the full declaration shall match it
11207 Check_Possible_Deferred_Completion
11209 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11210 Curr_Obj_Def => Obj_Def);
11212 Set_Full_View (Prev, Id);
11213 Set_Is_Public (Id, Is_Public (Prev));
11214 Set_Is_Internal (Id);
11215 Append_Entity (Id, Current_Scope);
11217 -- Check ALIASED present if present before (RM 7.4(7))
11219 if Is_Aliased (Prev)
11220 and then not Aliased_Present (N)
11222 Error_Msg_Sloc := Sloc (Prev);
11223 Error_Msg_N ("ALIASED required (see declaration#)", N);
11226 -- Check that placement is in private part and that the incomplete
11227 -- declaration appeared in the visible part.
11229 if Ekind (Current_Scope) = E_Package
11230 and then not In_Private_Part (Current_Scope)
11232 Error_Msg_Sloc := Sloc (Prev);
11234 ("full constant for declaration#"
11235 & " must be in private part", N);
11237 elsif Ekind (Current_Scope) = E_Package
11239 List_Containing (Parent (Prev)) /=
11240 Visible_Declarations (Package_Specification (Current_Scope))
11243 ("deferred constant must be declared in visible part",
11247 if Is_Access_Type (T)
11248 and then Nkind (Expression (N)) = N_Allocator
11250 Check_Recursive_Declaration (Designated_Type (T));
11253 -- A deferred constant is a visible entity. If type has invariants,
11254 -- verify that the initial value satisfies them.
11256 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
11258 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
11261 end Constant_Redeclaration;
11263 ----------------------
11264 -- Constrain_Access --
11265 ----------------------
11267 procedure Constrain_Access
11268 (Def_Id : in out Entity_Id;
11270 Related_Nod : Node_Id)
11272 T : constant Entity_Id := Entity (Subtype_Mark (S));
11273 Desig_Type : constant Entity_Id := Designated_Type (T);
11274 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
11275 Constraint_OK : Boolean := True;
11278 if Is_Array_Type (Desig_Type) then
11279 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
11281 elsif (Is_Record_Type (Desig_Type)
11282 or else Is_Incomplete_Or_Private_Type (Desig_Type))
11283 and then not Is_Constrained (Desig_Type)
11285 -- ??? The following code is a temporary bypass to ignore a
11286 -- discriminant constraint on access type if it is constraining
11287 -- the current record. Avoid creating the implicit subtype of the
11288 -- record we are currently compiling since right now, we cannot
11289 -- handle these. For now, just return the access type itself.
11291 if Desig_Type = Current_Scope
11292 and then No (Def_Id)
11294 Set_Ekind (Desig_Subtype, E_Record_Subtype);
11295 Def_Id := Entity (Subtype_Mark (S));
11297 -- This call added to ensure that the constraint is analyzed
11298 -- (needed for a B test). Note that we still return early from
11299 -- this procedure to avoid recursive processing. ???
11301 Constrain_Discriminated_Type
11302 (Desig_Subtype, S, Related_Nod, For_Access => True);
11306 -- Enforce rule that the constraint is illegal if there is an
11307 -- unconstrained view of the designated type. This means that the
11308 -- partial view (either a private type declaration or a derivation
11309 -- from a private type) has no discriminants. (Defect Report
11310 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
11312 -- Rule updated for Ada 2005: The private type is said to have
11313 -- a constrained partial view, given that objects of the type
11314 -- can be declared. Furthermore, the rule applies to all access
11315 -- types, unlike the rule concerning default discriminants (see
11318 if (Ekind (T) = E_General_Access_Type
11319 or else Ada_Version >= Ada_2005)
11320 and then Has_Private_Declaration (Desig_Type)
11321 and then In_Open_Scopes (Scope (Desig_Type))
11322 and then Has_Discriminants (Desig_Type)
11325 Pack : constant Node_Id :=
11326 Unit_Declaration_Node (Scope (Desig_Type));
11331 if Nkind (Pack) = N_Package_Declaration then
11332 Decls := Visible_Declarations (Specification (Pack));
11333 Decl := First (Decls);
11334 while Present (Decl) loop
11335 if (Nkind (Decl) = N_Private_Type_Declaration
11337 Chars (Defining_Identifier (Decl)) =
11338 Chars (Desig_Type))
11341 (Nkind (Decl) = N_Full_Type_Declaration
11343 Chars (Defining_Identifier (Decl)) =
11345 and then Is_Derived_Type (Desig_Type)
11347 Has_Private_Declaration (Etype (Desig_Type)))
11349 if No (Discriminant_Specifications (Decl)) then
11351 ("cannot constrain access type if designated " &
11352 "type has constrained partial view", S);
11364 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
11365 For_Access => True);
11367 elsif (Is_Task_Type (Desig_Type)
11368 or else Is_Protected_Type (Desig_Type))
11369 and then not Is_Constrained (Desig_Type)
11371 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
11374 Error_Msg_N ("invalid constraint on access type", S);
11375 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
11376 Constraint_OK := False;
11379 if No (Def_Id) then
11380 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
11382 Set_Ekind (Def_Id, E_Access_Subtype);
11385 if Constraint_OK then
11386 Set_Etype (Def_Id, Base_Type (T));
11388 if Is_Private_Type (Desig_Type) then
11389 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
11392 Set_Etype (Def_Id, Any_Type);
11395 Set_Size_Info (Def_Id, T);
11396 Set_Is_Constrained (Def_Id, Constraint_OK);
11397 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
11398 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11399 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
11401 Conditional_Delay (Def_Id, T);
11403 -- AI-363 : Subtypes of general access types whose designated types have
11404 -- default discriminants are disallowed. In instances, the rule has to
11405 -- be checked against the actual, of which T is the subtype. In a
11406 -- generic body, the rule is checked assuming that the actual type has
11407 -- defaulted discriminants.
11409 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
11410 if Ekind (Base_Type (T)) = E_General_Access_Type
11411 and then Has_Defaulted_Discriminants (Desig_Type)
11413 if Ada_Version < Ada_2005 then
11415 ("access subtype of general access type would not " &
11416 "be allowed in Ada 2005?y?", S);
11419 ("access subtype of general access type not allowed", S);
11422 Error_Msg_N ("\discriminants have defaults", S);
11424 elsif Is_Access_Type (T)
11425 and then Is_Generic_Type (Desig_Type)
11426 and then Has_Discriminants (Desig_Type)
11427 and then In_Package_Body (Current_Scope)
11429 if Ada_Version < Ada_2005 then
11431 ("access subtype would not be allowed in generic body " &
11432 "in Ada 2005?y?", S);
11435 ("access subtype not allowed in generic body", S);
11439 ("\designated type is a discriminated formal", S);
11442 end Constrain_Access;
11444 ---------------------
11445 -- Constrain_Array --
11446 ---------------------
11448 procedure Constrain_Array
11449 (Def_Id : in out Entity_Id;
11451 Related_Nod : Node_Id;
11452 Related_Id : Entity_Id;
11453 Suffix : Character)
11455 C : constant Node_Id := Constraint (SI);
11456 Number_Of_Constraints : Nat := 0;
11459 Constraint_OK : Boolean := True;
11462 T := Entity (Subtype_Mark (SI));
11464 if Is_Access_Type (T) then
11465 T := Designated_Type (T);
11468 -- If an index constraint follows a subtype mark in a subtype indication
11469 -- then the type or subtype denoted by the subtype mark must not already
11470 -- impose an index constraint. The subtype mark must denote either an
11471 -- unconstrained array type or an access type whose designated type
11472 -- is such an array type... (RM 3.6.1)
11474 if Is_Constrained (T) then
11475 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
11476 Constraint_OK := False;
11479 S := First (Constraints (C));
11480 while Present (S) loop
11481 Number_Of_Constraints := Number_Of_Constraints + 1;
11485 -- In either case, the index constraint must provide a discrete
11486 -- range for each index of the array type and the type of each
11487 -- discrete range must be the same as that of the corresponding
11488 -- index. (RM 3.6.1)
11490 if Number_Of_Constraints /= Number_Dimensions (T) then
11491 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
11492 Constraint_OK := False;
11495 S := First (Constraints (C));
11496 Index := First_Index (T);
11499 -- Apply constraints to each index type
11501 for J in 1 .. Number_Of_Constraints loop
11502 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
11510 if No (Def_Id) then
11512 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
11513 Set_Parent (Def_Id, Related_Nod);
11516 Set_Ekind (Def_Id, E_Array_Subtype);
11519 Set_Size_Info (Def_Id, (T));
11520 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11521 Set_Etype (Def_Id, Base_Type (T));
11523 if Constraint_OK then
11524 Set_First_Index (Def_Id, First (Constraints (C)));
11526 Set_First_Index (Def_Id, First_Index (T));
11529 Set_Is_Constrained (Def_Id, True);
11530 Set_Is_Aliased (Def_Id, Is_Aliased (T));
11531 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11533 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
11534 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
11536 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
11537 -- We need to initialize the attribute because if Def_Id is previously
11538 -- analyzed through a limited_with clause, it will have the attributes
11539 -- of an incomplete type, one of which is an Elist that overlaps the
11540 -- Packed_Array_Impl_Type field.
11542 Set_Packed_Array_Impl_Type (Def_Id, Empty);
11544 -- Build a freeze node if parent still needs one. Also make sure that
11545 -- the Depends_On_Private status is set because the subtype will need
11546 -- reprocessing at the time the base type does, and also we must set a
11547 -- conditional delay.
11549 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
11550 Conditional_Delay (Def_Id, T);
11551 end Constrain_Array;
11553 ------------------------------
11554 -- Constrain_Component_Type --
11555 ------------------------------
11557 function Constrain_Component_Type
11559 Constrained_Typ : Entity_Id;
11560 Related_Node : Node_Id;
11562 Constraints : Elist_Id) return Entity_Id
11564 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
11565 Compon_Type : constant Entity_Id := Etype (Comp);
11567 function Build_Constrained_Array_Type
11568 (Old_Type : Entity_Id) return Entity_Id;
11569 -- If Old_Type is an array type, one of whose indexes is constrained
11570 -- by a discriminant, build an Itype whose constraint replaces the
11571 -- discriminant with its value in the constraint.
11573 function Build_Constrained_Discriminated_Type
11574 (Old_Type : Entity_Id) return Entity_Id;
11575 -- Ditto for record components
11577 function Build_Constrained_Access_Type
11578 (Old_Type : Entity_Id) return Entity_Id;
11579 -- Ditto for access types. Makes use of previous two functions, to
11580 -- constrain designated type.
11582 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
11583 -- T is an array or discriminated type, C is a list of constraints
11584 -- that apply to T. This routine builds the constrained subtype.
11586 function Is_Discriminant (Expr : Node_Id) return Boolean;
11587 -- Returns True if Expr is a discriminant
11589 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
11590 -- Find the value of discriminant Discrim in Constraint
11592 -----------------------------------
11593 -- Build_Constrained_Access_Type --
11594 -----------------------------------
11596 function Build_Constrained_Access_Type
11597 (Old_Type : Entity_Id) return Entity_Id
11599 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
11601 Desig_Subtype : Entity_Id;
11605 -- if the original access type was not embedded in the enclosing
11606 -- type definition, there is no need to produce a new access
11607 -- subtype. In fact every access type with an explicit constraint
11608 -- generates an itype whose scope is the enclosing record.
11610 if not Is_Type (Scope (Old_Type)) then
11613 elsif Is_Array_Type (Desig_Type) then
11614 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
11616 elsif Has_Discriminants (Desig_Type) then
11618 -- This may be an access type to an enclosing record type for
11619 -- which we are constructing the constrained components. Return
11620 -- the enclosing record subtype. This is not always correct,
11621 -- but avoids infinite recursion. ???
11623 Desig_Subtype := Any_Type;
11625 for J in reverse 0 .. Scope_Stack.Last loop
11626 Scop := Scope_Stack.Table (J).Entity;
11629 and then Base_Type (Scop) = Base_Type (Desig_Type)
11631 Desig_Subtype := Scop;
11634 exit when not Is_Type (Scop);
11637 if Desig_Subtype = Any_Type then
11639 Build_Constrained_Discriminated_Type (Desig_Type);
11646 if Desig_Subtype /= Desig_Type then
11648 -- The Related_Node better be here or else we won't be able
11649 -- to attach new itypes to a node in the tree.
11651 pragma Assert (Present (Related_Node));
11653 Itype := Create_Itype (E_Access_Subtype, Related_Node);
11655 Set_Etype (Itype, Base_Type (Old_Type));
11656 Set_Size_Info (Itype, (Old_Type));
11657 Set_Directly_Designated_Type (Itype, Desig_Subtype);
11658 Set_Depends_On_Private (Itype, Has_Private_Component
11660 Set_Is_Access_Constant (Itype, Is_Access_Constant
11663 -- The new itype needs freezing when it depends on a not frozen
11664 -- type and the enclosing subtype needs freezing.
11666 if Has_Delayed_Freeze (Constrained_Typ)
11667 and then not Is_Frozen (Constrained_Typ)
11669 Conditional_Delay (Itype, Base_Type (Old_Type));
11677 end Build_Constrained_Access_Type;
11679 ----------------------------------
11680 -- Build_Constrained_Array_Type --
11681 ----------------------------------
11683 function Build_Constrained_Array_Type
11684 (Old_Type : Entity_Id) return Entity_Id
11688 Old_Index : Node_Id;
11689 Range_Node : Node_Id;
11690 Constr_List : List_Id;
11692 Need_To_Create_Itype : Boolean := False;
11695 Old_Index := First_Index (Old_Type);
11696 while Present (Old_Index) loop
11697 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11699 if Is_Discriminant (Lo_Expr)
11700 or else Is_Discriminant (Hi_Expr)
11702 Need_To_Create_Itype := True;
11705 Next_Index (Old_Index);
11708 if Need_To_Create_Itype then
11709 Constr_List := New_List;
11711 Old_Index := First_Index (Old_Type);
11712 while Present (Old_Index) loop
11713 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11715 if Is_Discriminant (Lo_Expr) then
11716 Lo_Expr := Get_Discr_Value (Lo_Expr);
11719 if Is_Discriminant (Hi_Expr) then
11720 Hi_Expr := Get_Discr_Value (Hi_Expr);
11725 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11727 Append (Range_Node, To => Constr_List);
11729 Next_Index (Old_Index);
11732 return Build_Subtype (Old_Type, Constr_List);
11737 end Build_Constrained_Array_Type;
11739 ------------------------------------------
11740 -- Build_Constrained_Discriminated_Type --
11741 ------------------------------------------
11743 function Build_Constrained_Discriminated_Type
11744 (Old_Type : Entity_Id) return Entity_Id
11747 Constr_List : List_Id;
11748 Old_Constraint : Elmt_Id;
11750 Need_To_Create_Itype : Boolean := False;
11753 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11754 while Present (Old_Constraint) loop
11755 Expr := Node (Old_Constraint);
11757 if Is_Discriminant (Expr) then
11758 Need_To_Create_Itype := True;
11761 Next_Elmt (Old_Constraint);
11764 if Need_To_Create_Itype then
11765 Constr_List := New_List;
11767 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11768 while Present (Old_Constraint) loop
11769 Expr := Node (Old_Constraint);
11771 if Is_Discriminant (Expr) then
11772 Expr := Get_Discr_Value (Expr);
11775 Append (New_Copy_Tree (Expr), To => Constr_List);
11777 Next_Elmt (Old_Constraint);
11780 return Build_Subtype (Old_Type, Constr_List);
11785 end Build_Constrained_Discriminated_Type;
11787 -------------------
11788 -- Build_Subtype --
11789 -------------------
11791 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11793 Subtyp_Decl : Node_Id;
11794 Def_Id : Entity_Id;
11795 Btyp : Entity_Id := Base_Type (T);
11798 -- The Related_Node better be here or else we won't be able to
11799 -- attach new itypes to a node in the tree.
11801 pragma Assert (Present (Related_Node));
11803 -- If the view of the component's type is incomplete or private
11804 -- with unknown discriminants, then the constraint must be applied
11805 -- to the full type.
11807 if Has_Unknown_Discriminants (Btyp)
11808 and then Present (Underlying_Type (Btyp))
11810 Btyp := Underlying_Type (Btyp);
11814 Make_Subtype_Indication (Loc,
11815 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11816 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11818 Def_Id := Create_Itype (Ekind (T), Related_Node);
11821 Make_Subtype_Declaration (Loc,
11822 Defining_Identifier => Def_Id,
11823 Subtype_Indication => Indic);
11825 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11827 -- Itypes must be analyzed with checks off (see package Itypes)
11829 Analyze (Subtyp_Decl, Suppress => All_Checks);
11834 ---------------------
11835 -- Get_Discr_Value --
11836 ---------------------
11838 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11843 -- The discriminant may be declared for the type, in which case we
11844 -- find it by iterating over the list of discriminants. If the
11845 -- discriminant is inherited from a parent type, it appears as the
11846 -- corresponding discriminant of the current type. This will be the
11847 -- case when constraining an inherited component whose constraint is
11848 -- given by a discriminant of the parent.
11850 D := First_Discriminant (Typ);
11851 E := First_Elmt (Constraints);
11853 while Present (D) loop
11854 if D = Entity (Discrim)
11855 or else D = CR_Discriminant (Entity (Discrim))
11856 or else Corresponding_Discriminant (D) = Entity (Discrim)
11861 Next_Discriminant (D);
11865 -- The Corresponding_Discriminant mechanism is incomplete, because
11866 -- the correspondence between new and old discriminants is not one
11867 -- to one: one new discriminant can constrain several old ones. In
11868 -- that case, scan sequentially the stored_constraint, the list of
11869 -- discriminants of the parents, and the constraints.
11871 -- Previous code checked for the present of the Stored_Constraint
11872 -- list for the derived type, but did not use it at all. Should it
11873 -- be present when the component is a discriminated task type?
11875 if Is_Derived_Type (Typ)
11876 and then Scope (Entity (Discrim)) = Etype (Typ)
11878 D := First_Discriminant (Etype (Typ));
11879 E := First_Elmt (Constraints);
11880 while Present (D) loop
11881 if D = Entity (Discrim) then
11885 Next_Discriminant (D);
11890 -- Something is wrong if we did not find the value
11892 raise Program_Error;
11893 end Get_Discr_Value;
11895 ---------------------
11896 -- Is_Discriminant --
11897 ---------------------
11899 function Is_Discriminant (Expr : Node_Id) return Boolean is
11900 Discrim_Scope : Entity_Id;
11903 if Denotes_Discriminant (Expr) then
11904 Discrim_Scope := Scope (Entity (Expr));
11906 -- Either we have a reference to one of Typ's discriminants,
11908 pragma Assert (Discrim_Scope = Typ
11910 -- or to the discriminants of the parent type, in the case
11911 -- of a derivation of a tagged type with variants.
11913 or else Discrim_Scope = Etype (Typ)
11914 or else Full_View (Discrim_Scope) = Etype (Typ)
11916 -- or same as above for the case where the discriminants
11917 -- were declared in Typ's private view.
11919 or else (Is_Private_Type (Discrim_Scope)
11920 and then Chars (Discrim_Scope) = Chars (Typ))
11922 -- or else we are deriving from the full view and the
11923 -- discriminant is declared in the private entity.
11925 or else (Is_Private_Type (Typ)
11926 and then Chars (Discrim_Scope) = Chars (Typ))
11928 -- Or we are constrained the corresponding record of a
11929 -- synchronized type that completes a private declaration.
11931 or else (Is_Concurrent_Record_Type (Typ)
11933 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11935 -- or we have a class-wide type, in which case make sure the
11936 -- discriminant found belongs to the root type.
11938 or else (Is_Class_Wide_Type (Typ)
11939 and then Etype (Typ) = Discrim_Scope));
11944 -- In all other cases we have something wrong
11947 end Is_Discriminant;
11949 -- Start of processing for Constrain_Component_Type
11952 if Nkind (Parent (Comp)) = N_Component_Declaration
11953 and then Comes_From_Source (Parent (Comp))
11954 and then Comes_From_Source
11955 (Subtype_Indication (Component_Definition (Parent (Comp))))
11958 (Subtype_Indication (Component_Definition (Parent (Comp))))
11960 return Compon_Type;
11962 elsif Is_Array_Type (Compon_Type) then
11963 return Build_Constrained_Array_Type (Compon_Type);
11965 elsif Has_Discriminants (Compon_Type) then
11966 return Build_Constrained_Discriminated_Type (Compon_Type);
11968 elsif Is_Access_Type (Compon_Type) then
11969 return Build_Constrained_Access_Type (Compon_Type);
11972 return Compon_Type;
11974 end Constrain_Component_Type;
11976 --------------------------
11977 -- Constrain_Concurrent --
11978 --------------------------
11980 -- For concurrent types, the associated record value type carries the same
11981 -- discriminants, so when we constrain a concurrent type, we must constrain
11982 -- the corresponding record type as well.
11984 procedure Constrain_Concurrent
11985 (Def_Id : in out Entity_Id;
11987 Related_Nod : Node_Id;
11988 Related_Id : Entity_Id;
11989 Suffix : Character)
11991 -- Retrieve Base_Type to ensure getting to the concurrent type in the
11992 -- case of a private subtype (needed when only doing semantic analysis).
11994 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
11998 if Is_Access_Type (T_Ent) then
11999 T_Ent := Designated_Type (T_Ent);
12002 T_Val := Corresponding_Record_Type (T_Ent);
12004 if Present (T_Val) then
12006 if No (Def_Id) then
12007 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12010 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12012 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12013 Set_Corresponding_Record_Type (Def_Id,
12014 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12017 -- If there is no associated record, expansion is disabled and this
12018 -- is a generic context. Create a subtype in any case, so that
12019 -- semantic analysis can proceed.
12021 if No (Def_Id) then
12022 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12025 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12027 end Constrain_Concurrent;
12029 ------------------------------------
12030 -- Constrain_Corresponding_Record --
12031 ------------------------------------
12033 function Constrain_Corresponding_Record
12034 (Prot_Subt : Entity_Id;
12035 Corr_Rec : Entity_Id;
12036 Related_Nod : Node_Id) return Entity_Id
12038 T_Sub : constant Entity_Id :=
12039 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12042 Set_Etype (T_Sub, Corr_Rec);
12043 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12044 Set_Is_Constrained (T_Sub, True);
12045 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12046 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12048 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12049 Set_Discriminant_Constraint
12050 (T_Sub, Discriminant_Constraint (Prot_Subt));
12051 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12052 Create_Constrained_Components
12053 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12056 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12058 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12059 Conditional_Delay (T_Sub, Corr_Rec);
12062 -- This is a component subtype: it will be frozen in the context of
12063 -- the enclosing record's init_proc, so that discriminant references
12064 -- are resolved to discriminals. (Note: we used to skip freezing
12065 -- altogether in that case, which caused errors downstream for
12066 -- components of a bit packed array type).
12068 Set_Has_Delayed_Freeze (T_Sub);
12072 end Constrain_Corresponding_Record;
12074 -----------------------
12075 -- Constrain_Decimal --
12076 -----------------------
12078 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12079 T : constant Entity_Id := Entity (Subtype_Mark (S));
12080 C : constant Node_Id := Constraint (S);
12081 Loc : constant Source_Ptr := Sloc (C);
12082 Range_Expr : Node_Id;
12083 Digits_Expr : Node_Id;
12088 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12090 if Nkind (C) = N_Range_Constraint then
12091 Range_Expr := Range_Expression (C);
12092 Digits_Val := Digits_Value (T);
12095 pragma Assert (Nkind (C) = N_Digits_Constraint);
12097 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12099 Digits_Expr := Digits_Expression (C);
12100 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12102 Check_Digits_Expression (Digits_Expr);
12103 Digits_Val := Expr_Value (Digits_Expr);
12105 if Digits_Val > Digits_Value (T) then
12107 ("digits expression is incompatible with subtype", C);
12108 Digits_Val := Digits_Value (T);
12111 if Present (Range_Constraint (C)) then
12112 Range_Expr := Range_Expression (Range_Constraint (C));
12114 Range_Expr := Empty;
12118 Set_Etype (Def_Id, Base_Type (T));
12119 Set_Size_Info (Def_Id, (T));
12120 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12121 Set_Delta_Value (Def_Id, Delta_Value (T));
12122 Set_Scale_Value (Def_Id, Scale_Value (T));
12123 Set_Small_Value (Def_Id, Small_Value (T));
12124 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12125 Set_Digits_Value (Def_Id, Digits_Val);
12127 -- Manufacture range from given digits value if no range present
12129 if No (Range_Expr) then
12130 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12134 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12136 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12139 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12140 Set_Discrete_RM_Size (Def_Id);
12142 -- Unconditionally delay the freeze, since we cannot set size
12143 -- information in all cases correctly until the freeze point.
12145 Set_Has_Delayed_Freeze (Def_Id);
12146 end Constrain_Decimal;
12148 ----------------------------------
12149 -- Constrain_Discriminated_Type --
12150 ----------------------------------
12152 procedure Constrain_Discriminated_Type
12153 (Def_Id : Entity_Id;
12155 Related_Nod : Node_Id;
12156 For_Access : Boolean := False)
12158 E : constant Entity_Id := Entity (Subtype_Mark (S));
12161 Elist : Elist_Id := New_Elmt_List;
12163 procedure Fixup_Bad_Constraint;
12164 -- This is called after finding a bad constraint, and after having
12165 -- posted an appropriate error message. The mission is to leave the
12166 -- entity T in as reasonable state as possible.
12168 --------------------------
12169 -- Fixup_Bad_Constraint --
12170 --------------------------
12172 procedure Fixup_Bad_Constraint is
12174 -- Set a reasonable Ekind for the entity. For an incomplete type,
12175 -- we can't do much, but for other types, we can set the proper
12176 -- corresponding subtype kind.
12178 if Ekind (T) = E_Incomplete_Type then
12179 Set_Ekind (Def_Id, Ekind (T));
12181 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12184 -- Set Etype to the known type, to reduce chances of cascaded errors
12186 Set_Etype (Def_Id, E);
12187 Set_Error_Posted (Def_Id);
12188 end Fixup_Bad_Constraint;
12190 -- Start of processing for Constrain_Discriminated_Type
12193 C := Constraint (S);
12195 -- A discriminant constraint is only allowed in a subtype indication,
12196 -- after a subtype mark. This subtype mark must denote either a type
12197 -- with discriminants, or an access type whose designated type is a
12198 -- type with discriminants. A discriminant constraint specifies the
12199 -- values of these discriminants (RM 3.7.2(5)).
12201 T := Base_Type (Entity (Subtype_Mark (S)));
12203 if Is_Access_Type (T) then
12204 T := Designated_Type (T);
12207 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12208 -- Avoid generating an error for access-to-incomplete subtypes.
12210 if Ada_Version >= Ada_2005
12211 and then Ekind (T) = E_Incomplete_Type
12212 and then Nkind (Parent (S)) = N_Subtype_Declaration
12213 and then not Is_Itype (Def_Id)
12215 -- A little sanity check, emit an error message if the type
12216 -- has discriminants to begin with. Type T may be a regular
12217 -- incomplete type or imported via a limited with clause.
12219 if Has_Discriminants (T)
12220 or else (From_Limited_With (T)
12221 and then Present (Non_Limited_View (T))
12222 and then Nkind (Parent (Non_Limited_View (T))) =
12223 N_Full_Type_Declaration
12224 and then Present (Discriminant_Specifications
12225 (Parent (Non_Limited_View (T)))))
12228 ("(Ada 2005) incomplete subtype may not be constrained", C);
12230 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12233 Fixup_Bad_Constraint;
12236 -- Check that the type has visible discriminants. The type may be
12237 -- a private type with unknown discriminants whose full view has
12238 -- discriminants which are invisible.
12240 elsif not Has_Discriminants (T)
12242 (Has_Unknown_Discriminants (T)
12243 and then Is_Private_Type (T))
12245 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12246 Fixup_Bad_Constraint;
12249 elsif Is_Constrained (E)
12250 or else (Ekind (E) = E_Class_Wide_Subtype
12251 and then Present (Discriminant_Constraint (E)))
12253 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
12254 Fixup_Bad_Constraint;
12258 -- T may be an unconstrained subtype (e.g. a generic actual).
12259 -- Constraint applies to the base type.
12261 T := Base_Type (T);
12263 Elist := Build_Discriminant_Constraints (T, S);
12265 -- If the list returned was empty we had an error in building the
12266 -- discriminant constraint. We have also already signalled an error
12267 -- in the incomplete type case
12269 if Is_Empty_Elmt_List (Elist) then
12270 Fixup_Bad_Constraint;
12274 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
12275 end Constrain_Discriminated_Type;
12277 ---------------------------
12278 -- Constrain_Enumeration --
12279 ---------------------------
12281 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
12282 T : constant Entity_Id := Entity (Subtype_Mark (S));
12283 C : constant Node_Id := Constraint (S);
12286 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12288 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
12290 Set_Etype (Def_Id, Base_Type (T));
12291 Set_Size_Info (Def_Id, (T));
12292 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12293 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12295 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12297 Set_Discrete_RM_Size (Def_Id);
12298 end Constrain_Enumeration;
12300 ----------------------
12301 -- Constrain_Float --
12302 ----------------------
12304 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
12305 T : constant Entity_Id := Entity (Subtype_Mark (S));
12311 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
12313 Set_Etype (Def_Id, Base_Type (T));
12314 Set_Size_Info (Def_Id, (T));
12315 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12317 -- Process the constraint
12319 C := Constraint (S);
12321 -- Digits constraint present
12323 if Nkind (C) = N_Digits_Constraint then
12325 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12326 Check_Restriction (No_Obsolescent_Features, C);
12328 if Warn_On_Obsolescent_Feature then
12330 ("subtype digits constraint is an " &
12331 "obsolescent feature (RM J.3(8))?j?", C);
12334 D := Digits_Expression (C);
12335 Analyze_And_Resolve (D, Any_Integer);
12336 Check_Digits_Expression (D);
12337 Set_Digits_Value (Def_Id, Expr_Value (D));
12339 -- Check that digits value is in range. Obviously we can do this
12340 -- at compile time, but it is strictly a runtime check, and of
12341 -- course there is an ACVC test that checks this.
12343 if Digits_Value (Def_Id) > Digits_Value (T) then
12344 Error_Msg_Uint_1 := Digits_Value (T);
12345 Error_Msg_N ("??digits value is too large, maximum is ^", D);
12347 Make_Raise_Constraint_Error (Sloc (D),
12348 Reason => CE_Range_Check_Failed);
12349 Insert_Action (Declaration_Node (Def_Id), Rais);
12352 C := Range_Constraint (C);
12354 -- No digits constraint present
12357 Set_Digits_Value (Def_Id, Digits_Value (T));
12360 -- Range constraint present
12362 if Nkind (C) = N_Range_Constraint then
12363 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12365 -- No range constraint present
12368 pragma Assert (No (C));
12369 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12372 Set_Is_Constrained (Def_Id);
12373 end Constrain_Float;
12375 ---------------------
12376 -- Constrain_Index --
12377 ---------------------
12379 procedure Constrain_Index
12382 Related_Nod : Node_Id;
12383 Related_Id : Entity_Id;
12384 Suffix : Character;
12385 Suffix_Index : Nat)
12387 Def_Id : Entity_Id;
12388 R : Node_Id := Empty;
12389 T : constant Entity_Id := Etype (Index);
12392 if Nkind (S) = N_Range
12394 (Nkind (S) = N_Attribute_Reference
12395 and then Attribute_Name (S) = Name_Range)
12397 -- A Range attribute will be transformed into N_Range by Resolve
12403 Process_Range_Expr_In_Decl (R, T);
12405 if not Error_Posted (S)
12407 (Nkind (S) /= N_Range
12408 or else not Covers (T, (Etype (Low_Bound (S))))
12409 or else not Covers (T, (Etype (High_Bound (S)))))
12411 if Base_Type (T) /= Any_Type
12412 and then Etype (Low_Bound (S)) /= Any_Type
12413 and then Etype (High_Bound (S)) /= Any_Type
12415 Error_Msg_N ("range expected", S);
12419 elsif Nkind (S) = N_Subtype_Indication then
12421 -- The parser has verified that this is a discrete indication
12423 Resolve_Discrete_Subtype_Indication (S, T);
12424 R := Range_Expression (Constraint (S));
12426 -- Capture values of bounds and generate temporaries for them if
12427 -- needed, since checks may cause duplication of the expressions
12428 -- which must not be reevaluated.
12430 -- The forced evaluation removes side effects from expressions, which
12431 -- should occur also in GNATprove mode. Otherwise, we end up with
12432 -- unexpected insertions of actions at places where this is not
12433 -- supposed to occur, e.g. on default parameters of a call.
12435 if Expander_Active or GNATprove_Mode then
12436 Force_Evaluation (Low_Bound (R));
12437 Force_Evaluation (High_Bound (R));
12440 elsif Nkind (S) = N_Discriminant_Association then
12442 -- Syntactically valid in subtype indication
12444 Error_Msg_N ("invalid index constraint", S);
12445 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12448 -- Subtype_Mark case, no anonymous subtypes to construct
12453 if Is_Entity_Name (S) then
12454 if not Is_Type (Entity (S)) then
12455 Error_Msg_N ("expect subtype mark for index constraint", S);
12457 elsif Base_Type (Entity (S)) /= Base_Type (T) then
12458 Wrong_Type (S, Base_Type (T));
12460 -- Check error of subtype with predicate in index constraint
12463 Bad_Predicated_Subtype_Use
12464 ("subtype& has predicate, not allowed in index constraint",
12471 Error_Msg_N ("invalid index constraint", S);
12472 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12478 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
12480 Set_Etype (Def_Id, Base_Type (T));
12482 if Is_Modular_Integer_Type (T) then
12483 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12485 elsif Is_Integer_Type (T) then
12486 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12489 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12490 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12491 Set_First_Literal (Def_Id, First_Literal (T));
12494 Set_Size_Info (Def_Id, (T));
12495 Set_RM_Size (Def_Id, RM_Size (T));
12496 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12498 Set_Scalar_Range (Def_Id, R);
12500 Set_Etype (S, Def_Id);
12501 Set_Discrete_RM_Size (Def_Id);
12502 end Constrain_Index;
12504 -----------------------
12505 -- Constrain_Integer --
12506 -----------------------
12508 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
12509 T : constant Entity_Id := Entity (Subtype_Mark (S));
12510 C : constant Node_Id := Constraint (S);
12513 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12515 if Is_Modular_Integer_Type (T) then
12516 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12518 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12521 Set_Etype (Def_Id, Base_Type (T));
12522 Set_Size_Info (Def_Id, (T));
12523 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12524 Set_Discrete_RM_Size (Def_Id);
12525 end Constrain_Integer;
12527 ------------------------------
12528 -- Constrain_Ordinary_Fixed --
12529 ------------------------------
12531 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
12532 T : constant Entity_Id := Entity (Subtype_Mark (S));
12538 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
12539 Set_Etype (Def_Id, Base_Type (T));
12540 Set_Size_Info (Def_Id, (T));
12541 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12542 Set_Small_Value (Def_Id, Small_Value (T));
12544 -- Process the constraint
12546 C := Constraint (S);
12548 -- Delta constraint present
12550 if Nkind (C) = N_Delta_Constraint then
12552 Check_SPARK_Restriction ("delta constraint is not allowed", S);
12553 Check_Restriction (No_Obsolescent_Features, C);
12555 if Warn_On_Obsolescent_Feature then
12557 ("subtype delta constraint is an " &
12558 "obsolescent feature (RM J.3(7))?j?");
12561 D := Delta_Expression (C);
12562 Analyze_And_Resolve (D, Any_Real);
12563 Check_Delta_Expression (D);
12564 Set_Delta_Value (Def_Id, Expr_Value_R (D));
12566 -- Check that delta value is in range. Obviously we can do this
12567 -- at compile time, but it is strictly a runtime check, and of
12568 -- course there is an ACVC test that checks this.
12570 if Delta_Value (Def_Id) < Delta_Value (T) then
12571 Error_Msg_N ("??delta value is too small", D);
12573 Make_Raise_Constraint_Error (Sloc (D),
12574 Reason => CE_Range_Check_Failed);
12575 Insert_Action (Declaration_Node (Def_Id), Rais);
12578 C := Range_Constraint (C);
12580 -- No delta constraint present
12583 Set_Delta_Value (Def_Id, Delta_Value (T));
12586 -- Range constraint present
12588 if Nkind (C) = N_Range_Constraint then
12589 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12591 -- No range constraint present
12594 pragma Assert (No (C));
12595 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12599 Set_Discrete_RM_Size (Def_Id);
12601 -- Unconditionally delay the freeze, since we cannot set size
12602 -- information in all cases correctly until the freeze point.
12604 Set_Has_Delayed_Freeze (Def_Id);
12605 end Constrain_Ordinary_Fixed;
12607 -----------------------
12608 -- Contain_Interface --
12609 -----------------------
12611 function Contain_Interface
12612 (Iface : Entity_Id;
12613 Ifaces : Elist_Id) return Boolean
12615 Iface_Elmt : Elmt_Id;
12618 if Present (Ifaces) then
12619 Iface_Elmt := First_Elmt (Ifaces);
12620 while Present (Iface_Elmt) loop
12621 if Node (Iface_Elmt) = Iface then
12625 Next_Elmt (Iface_Elmt);
12630 end Contain_Interface;
12632 ---------------------------
12633 -- Convert_Scalar_Bounds --
12634 ---------------------------
12636 procedure Convert_Scalar_Bounds
12638 Parent_Type : Entity_Id;
12639 Derived_Type : Entity_Id;
12642 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
12649 -- Defend against previous errors
12651 if No (Scalar_Range (Derived_Type)) then
12652 Check_Error_Detected;
12656 Lo := Build_Scalar_Bound
12657 (Type_Low_Bound (Derived_Type),
12658 Parent_Type, Implicit_Base);
12660 Hi := Build_Scalar_Bound
12661 (Type_High_Bound (Derived_Type),
12662 Parent_Type, Implicit_Base);
12669 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
12671 Set_Parent (Rng, N);
12672 Set_Scalar_Range (Derived_Type, Rng);
12674 -- Analyze the bounds
12676 Analyze_And_Resolve (Lo, Implicit_Base);
12677 Analyze_And_Resolve (Hi, Implicit_Base);
12679 -- Analyze the range itself, except that we do not analyze it if
12680 -- the bounds are real literals, and we have a fixed-point type.
12681 -- The reason for this is that we delay setting the bounds in this
12682 -- case till we know the final Small and Size values (see circuit
12683 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12685 if Is_Fixed_Point_Type (Parent_Type)
12686 and then Nkind (Lo) = N_Real_Literal
12687 and then Nkind (Hi) = N_Real_Literal
12691 -- Here we do the analysis of the range
12693 -- Note: we do this manually, since if we do a normal Analyze and
12694 -- Resolve call, there are problems with the conversions used for
12695 -- the derived type range.
12698 Set_Etype (Rng, Implicit_Base);
12699 Set_Analyzed (Rng, True);
12701 end Convert_Scalar_Bounds;
12703 -------------------
12704 -- Copy_And_Swap --
12705 -------------------
12707 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12709 -- Initialize new full declaration entity by copying the pertinent
12710 -- fields of the corresponding private declaration entity.
12712 -- We temporarily set Ekind to a value appropriate for a type to
12713 -- avoid assert failures in Einfo from checking for setting type
12714 -- attributes on something that is not a type. Ekind (Priv) is an
12715 -- appropriate choice, since it allowed the attributes to be set
12716 -- in the first place. This Ekind value will be modified later.
12718 Set_Ekind (Full, Ekind (Priv));
12720 -- Also set Etype temporarily to Any_Type, again, in the absence
12721 -- of errors, it will be properly reset, and if there are errors,
12722 -- then we want a value of Any_Type to remain.
12724 Set_Etype (Full, Any_Type);
12726 -- Now start copying attributes
12728 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12730 if Has_Discriminants (Full) then
12731 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12732 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12735 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12736 Set_Homonym (Full, Homonym (Priv));
12737 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12738 Set_Is_Public (Full, Is_Public (Priv));
12739 Set_Is_Pure (Full, Is_Pure (Priv));
12740 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12741 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12742 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12743 Set_Has_Pragma_Unreferenced_Objects
12744 (Full, Has_Pragma_Unreferenced_Objects
12747 Conditional_Delay (Full, Priv);
12749 if Is_Tagged_Type (Full) then
12750 Set_Direct_Primitive_Operations (Full,
12751 Direct_Primitive_Operations (Priv));
12753 if Is_Base_Type (Priv) then
12754 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12758 Set_Is_Volatile (Full, Is_Volatile (Priv));
12759 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12760 Set_Scope (Full, Scope (Priv));
12761 Set_Next_Entity (Full, Next_Entity (Priv));
12762 Set_First_Entity (Full, First_Entity (Priv));
12763 Set_Last_Entity (Full, Last_Entity (Priv));
12765 -- If access types have been recorded for later handling, keep them in
12766 -- the full view so that they get handled when the full view freeze
12767 -- node is expanded.
12769 if Present (Freeze_Node (Priv))
12770 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12772 Ensure_Freeze_Node (Full);
12773 Set_Access_Types_To_Process
12774 (Freeze_Node (Full),
12775 Access_Types_To_Process (Freeze_Node (Priv)));
12778 -- Swap the two entities. Now Private is the full type entity and Full
12779 -- is the private one. They will be swapped back at the end of the
12780 -- private part. This swapping ensures that the entity that is visible
12781 -- in the private part is the full declaration.
12783 Exchange_Entities (Priv, Full);
12784 Append_Entity (Full, Scope (Full));
12787 -------------------------------------
12788 -- Copy_Array_Base_Type_Attributes --
12789 -------------------------------------
12791 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12793 Set_Component_Alignment (T1, Component_Alignment (T2));
12794 Set_Component_Type (T1, Component_Type (T2));
12795 Set_Component_Size (T1, Component_Size (T2));
12796 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12797 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12798 Set_Has_Protected (T1, Has_Protected (T2));
12799 Set_Has_Task (T1, Has_Task (T2));
12800 Set_Is_Packed (T1, Is_Packed (T2));
12801 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12802 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12803 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12804 end Copy_Array_Base_Type_Attributes;
12806 -----------------------------------
12807 -- Copy_Array_Subtype_Attributes --
12808 -----------------------------------
12810 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12812 Set_Size_Info (T1, T2);
12814 Set_First_Index (T1, First_Index (T2));
12815 Set_Is_Aliased (T1, Is_Aliased (T2));
12816 Set_Is_Volatile (T1, Is_Volatile (T2));
12817 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12818 Set_Is_Constrained (T1, Is_Constrained (T2));
12819 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12820 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12821 Set_Convention (T1, Convention (T2));
12822 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12823 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12824 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
12825 end Copy_Array_Subtype_Attributes;
12827 -----------------------------------
12828 -- Create_Constrained_Components --
12829 -----------------------------------
12831 procedure Create_Constrained_Components
12833 Decl_Node : Node_Id;
12835 Constraints : Elist_Id)
12837 Loc : constant Source_Ptr := Sloc (Subt);
12838 Comp_List : constant Elist_Id := New_Elmt_List;
12839 Parent_Type : constant Entity_Id := Etype (Typ);
12840 Assoc_List : constant List_Id := New_List;
12841 Discr_Val : Elmt_Id;
12845 Is_Static : Boolean := True;
12847 procedure Collect_Fixed_Components (Typ : Entity_Id);
12848 -- Collect parent type components that do not appear in a variant part
12850 procedure Create_All_Components;
12851 -- Iterate over Comp_List to create the components of the subtype
12853 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12854 -- Creates a new component from Old_Compon, copying all the fields from
12855 -- it, including its Etype, inserts the new component in the Subt entity
12856 -- chain and returns the new component.
12858 function Is_Variant_Record (T : Entity_Id) return Boolean;
12859 -- If true, and discriminants are static, collect only components from
12860 -- variants selected by discriminant values.
12862 ------------------------------
12863 -- Collect_Fixed_Components --
12864 ------------------------------
12866 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12868 -- Build association list for discriminants, and find components of the
12869 -- variant part selected by the values of the discriminants.
12871 Old_C := First_Discriminant (Typ);
12872 Discr_Val := First_Elmt (Constraints);
12873 while Present (Old_C) loop
12874 Append_To (Assoc_List,
12875 Make_Component_Association (Loc,
12876 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12877 Expression => New_Copy (Node (Discr_Val))));
12879 Next_Elmt (Discr_Val);
12880 Next_Discriminant (Old_C);
12883 -- The tag and the possible parent component are unconditionally in
12886 if Is_Tagged_Type (Typ)
12887 or else Has_Controlled_Component (Typ)
12889 Old_C := First_Component (Typ);
12890 while Present (Old_C) loop
12891 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
12892 Append_Elmt (Old_C, Comp_List);
12895 Next_Component (Old_C);
12898 end Collect_Fixed_Components;
12900 ---------------------------
12901 -- Create_All_Components --
12902 ---------------------------
12904 procedure Create_All_Components is
12908 Comp := First_Elmt (Comp_List);
12909 while Present (Comp) loop
12910 Old_C := Node (Comp);
12911 New_C := Create_Component (Old_C);
12915 Constrain_Component_Type
12916 (Old_C, Subt, Decl_Node, Typ, Constraints));
12917 Set_Is_Public (New_C, Is_Public (Subt));
12921 end Create_All_Components;
12923 ----------------------
12924 -- Create_Component --
12925 ----------------------
12927 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12928 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12931 if Ekind (Old_Compon) = E_Discriminant
12932 and then Is_Completely_Hidden (Old_Compon)
12934 -- This is a shadow discriminant created for a discriminant of
12935 -- the parent type, which needs to be present in the subtype.
12936 -- Give the shadow discriminant an internal name that cannot
12937 -- conflict with that of visible components.
12939 Set_Chars (New_Compon, New_Internal_Name ('C'));
12942 -- Set the parent so we have a proper link for freezing etc. This is
12943 -- not a real parent pointer, since of course our parent does not own
12944 -- up to us and reference us, we are an illegitimate child of the
12945 -- original parent.
12947 Set_Parent (New_Compon, Parent (Old_Compon));
12949 -- If the old component's Esize was already determined and is a
12950 -- static value, then the new component simply inherits it. Otherwise
12951 -- the old component's size may require run-time determination, but
12952 -- the new component's size still might be statically determinable
12953 -- (if, for example it has a static constraint). In that case we want
12954 -- Layout_Type to recompute the component's size, so we reset its
12955 -- size and positional fields.
12957 if Frontend_Layout_On_Target
12958 and then not Known_Static_Esize (Old_Compon)
12960 Set_Esize (New_Compon, Uint_0);
12961 Init_Normalized_First_Bit (New_Compon);
12962 Init_Normalized_Position (New_Compon);
12963 Init_Normalized_Position_Max (New_Compon);
12966 -- We do not want this node marked as Comes_From_Source, since
12967 -- otherwise it would get first class status and a separate cross-
12968 -- reference line would be generated. Illegitimate children do not
12969 -- rate such recognition.
12971 Set_Comes_From_Source (New_Compon, False);
12973 -- But it is a real entity, and a birth certificate must be properly
12974 -- registered by entering it into the entity list.
12976 Enter_Name (New_Compon);
12979 end Create_Component;
12981 -----------------------
12982 -- Is_Variant_Record --
12983 -----------------------
12985 function Is_Variant_Record (T : Entity_Id) return Boolean is
12987 return Nkind (Parent (T)) = N_Full_Type_Declaration
12988 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12989 and then Present (Component_List (Type_Definition (Parent (T))))
12992 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12993 end Is_Variant_Record;
12995 -- Start of processing for Create_Constrained_Components
12998 pragma Assert (Subt /= Base_Type (Subt));
12999 pragma Assert (Typ = Base_Type (Typ));
13001 Set_First_Entity (Subt, Empty);
13002 Set_Last_Entity (Subt, Empty);
13004 -- Check whether constraint is fully static, in which case we can
13005 -- optimize the list of components.
13007 Discr_Val := First_Elmt (Constraints);
13008 while Present (Discr_Val) loop
13009 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13010 Is_Static := False;
13014 Next_Elmt (Discr_Val);
13017 Set_Has_Static_Discriminants (Subt, Is_Static);
13021 -- Inherit the discriminants of the parent type
13023 Add_Discriminants : declare
13029 Old_C := First_Discriminant (Typ);
13031 while Present (Old_C) loop
13032 Num_Disc := Num_Disc + 1;
13033 New_C := Create_Component (Old_C);
13034 Set_Is_Public (New_C, Is_Public (Subt));
13035 Next_Discriminant (Old_C);
13038 -- For an untagged derived subtype, the number of discriminants may
13039 -- be smaller than the number of inherited discriminants, because
13040 -- several of them may be renamed by a single new discriminant or
13041 -- constrained. In this case, add the hidden discriminants back into
13042 -- the subtype, because they need to be present if the optimizer of
13043 -- the GCC 4.x back-end decides to break apart assignments between
13044 -- objects using the parent view into member-wise assignments.
13048 if Is_Derived_Type (Typ)
13049 and then not Is_Tagged_Type (Typ)
13051 Old_C := First_Stored_Discriminant (Typ);
13053 while Present (Old_C) loop
13054 Num_Gird := Num_Gird + 1;
13055 Next_Stored_Discriminant (Old_C);
13059 if Num_Gird > Num_Disc then
13061 -- Find out multiple uses of new discriminants, and add hidden
13062 -- components for the extra renamed discriminants. We recognize
13063 -- multiple uses through the Corresponding_Discriminant of a
13064 -- new discriminant: if it constrains several old discriminants,
13065 -- this field points to the last one in the parent type. The
13066 -- stored discriminants of the derived type have the same name
13067 -- as those of the parent.
13071 New_Discr : Entity_Id;
13072 Old_Discr : Entity_Id;
13075 Constr := First_Elmt (Stored_Constraint (Typ));
13076 Old_Discr := First_Stored_Discriminant (Typ);
13077 while Present (Constr) loop
13078 if Is_Entity_Name (Node (Constr))
13079 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13081 New_Discr := Entity (Node (Constr));
13083 if Chars (Corresponding_Discriminant (New_Discr)) /=
13086 -- The new discriminant has been used to rename a
13087 -- subsequent old discriminant. Introduce a shadow
13088 -- component for the current old discriminant.
13090 New_C := Create_Component (Old_Discr);
13091 Set_Original_Record_Component (New_C, Old_Discr);
13095 -- The constraint has eliminated the old discriminant.
13096 -- Introduce a shadow component.
13098 New_C := Create_Component (Old_Discr);
13099 Set_Original_Record_Component (New_C, Old_Discr);
13102 Next_Elmt (Constr);
13103 Next_Stored_Discriminant (Old_Discr);
13107 end Add_Discriminants;
13110 and then Is_Variant_Record (Typ)
13112 Collect_Fixed_Components (Typ);
13114 Gather_Components (
13116 Component_List (Type_Definition (Parent (Typ))),
13117 Governed_By => Assoc_List,
13119 Report_Errors => Errors);
13120 pragma Assert (not Errors);
13122 Create_All_Components;
13124 -- If the subtype declaration is created for a tagged type derivation
13125 -- with constraints, we retrieve the record definition of the parent
13126 -- type to select the components of the proper variant.
13129 and then Is_Tagged_Type (Typ)
13130 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13132 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13133 and then Is_Variant_Record (Parent_Type)
13135 Collect_Fixed_Components (Typ);
13137 Gather_Components (
13139 Component_List (Type_Definition (Parent (Parent_Type))),
13140 Governed_By => Assoc_List,
13142 Report_Errors => Errors);
13143 pragma Assert (not Errors);
13145 -- If the tagged derivation has a type extension, collect all the
13146 -- new components therein.
13149 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13151 Old_C := First_Component (Typ);
13152 while Present (Old_C) loop
13153 if Original_Record_Component (Old_C) = Old_C
13154 and then Chars (Old_C) /= Name_uTag
13155 and then Chars (Old_C) /= Name_uParent
13157 Append_Elmt (Old_C, Comp_List);
13160 Next_Component (Old_C);
13164 Create_All_Components;
13167 -- If discriminants are not static, or if this is a multi-level type
13168 -- extension, we have to include all components of the parent type.
13170 Old_C := First_Component (Typ);
13171 while Present (Old_C) loop
13172 New_C := Create_Component (Old_C);
13176 Constrain_Component_Type
13177 (Old_C, Subt, Decl_Node, Typ, Constraints));
13178 Set_Is_Public (New_C, Is_Public (Subt));
13180 Next_Component (Old_C);
13185 end Create_Constrained_Components;
13187 ------------------------------------------
13188 -- Decimal_Fixed_Point_Type_Declaration --
13189 ------------------------------------------
13191 procedure Decimal_Fixed_Point_Type_Declaration
13195 Loc : constant Source_Ptr := Sloc (Def);
13196 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13197 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13198 Implicit_Base : Entity_Id;
13205 Check_SPARK_Restriction
13206 ("decimal fixed point type is not allowed", Def);
13207 Check_Restriction (No_Fixed_Point, Def);
13209 -- Create implicit base type
13212 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13213 Set_Etype (Implicit_Base, Implicit_Base);
13215 -- Analyze and process delta expression
13217 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13219 Check_Delta_Expression (Delta_Expr);
13220 Delta_Val := Expr_Value_R (Delta_Expr);
13222 -- Check delta is power of 10, and determine scale value from it
13228 Scale_Val := Uint_0;
13231 if Val < Ureal_1 then
13232 while Val < Ureal_1 loop
13233 Val := Val * Ureal_10;
13234 Scale_Val := Scale_Val + 1;
13237 if Scale_Val > 18 then
13238 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13239 Scale_Val := UI_From_Int (+18);
13243 while Val > Ureal_1 loop
13244 Val := Val / Ureal_10;
13245 Scale_Val := Scale_Val - 1;
13248 if Scale_Val < -18 then
13249 Error_Msg_N ("scale is less than minimum value of -18", Def);
13250 Scale_Val := UI_From_Int (-18);
13254 if Val /= Ureal_1 then
13255 Error_Msg_N ("delta expression must be a power of 10", Def);
13256 Delta_Val := Ureal_10 ** (-Scale_Val);
13260 -- Set delta, scale and small (small = delta for decimal type)
13262 Set_Delta_Value (Implicit_Base, Delta_Val);
13263 Set_Scale_Value (Implicit_Base, Scale_Val);
13264 Set_Small_Value (Implicit_Base, Delta_Val);
13266 -- Analyze and process digits expression
13268 Analyze_And_Resolve (Digs_Expr, Any_Integer);
13269 Check_Digits_Expression (Digs_Expr);
13270 Digs_Val := Expr_Value (Digs_Expr);
13272 if Digs_Val > 18 then
13273 Digs_Val := UI_From_Int (+18);
13274 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
13277 Set_Digits_Value (Implicit_Base, Digs_Val);
13278 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
13280 -- Set range of base type from digits value for now. This will be
13281 -- expanded to represent the true underlying base range by Freeze.
13283 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
13285 -- Note: We leave size as zero for now, size will be set at freeze
13286 -- time. We have to do this for ordinary fixed-point, because the size
13287 -- depends on the specified small, and we might as well do the same for
13288 -- decimal fixed-point.
13290 pragma Assert (Esize (Implicit_Base) = Uint_0);
13292 -- If there are bounds given in the declaration use them as the
13293 -- bounds of the first named subtype.
13295 if Present (Real_Range_Specification (Def)) then
13297 RRS : constant Node_Id := Real_Range_Specification (Def);
13298 Low : constant Node_Id := Low_Bound (RRS);
13299 High : constant Node_Id := High_Bound (RRS);
13304 Analyze_And_Resolve (Low, Any_Real);
13305 Analyze_And_Resolve (High, Any_Real);
13306 Check_Real_Bound (Low);
13307 Check_Real_Bound (High);
13308 Low_Val := Expr_Value_R (Low);
13309 High_Val := Expr_Value_R (High);
13311 if Low_Val < (-Bound_Val) then
13313 ("range low bound too small for digits value", Low);
13314 Low_Val := -Bound_Val;
13317 if High_Val > Bound_Val then
13319 ("range high bound too large for digits value", High);
13320 High_Val := Bound_Val;
13323 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
13326 -- If no explicit range, use range that corresponds to given
13327 -- digits value. This will end up as the final range for the
13331 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
13334 -- Complete entity for first subtype
13336 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
13337 Set_Etype (T, Implicit_Base);
13338 Set_Size_Info (T, Implicit_Base);
13339 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
13340 Set_Digits_Value (T, Digs_Val);
13341 Set_Delta_Value (T, Delta_Val);
13342 Set_Small_Value (T, Delta_Val);
13343 Set_Scale_Value (T, Scale_Val);
13344 Set_Is_Constrained (T);
13345 end Decimal_Fixed_Point_Type_Declaration;
13347 -----------------------------------
13348 -- Derive_Progenitor_Subprograms --
13349 -----------------------------------
13351 procedure Derive_Progenitor_Subprograms
13352 (Parent_Type : Entity_Id;
13353 Tagged_Type : Entity_Id)
13358 Iface_Elmt : Elmt_Id;
13359 Iface_Subp : Entity_Id;
13360 New_Subp : Entity_Id := Empty;
13361 Prim_Elmt : Elmt_Id;
13366 pragma Assert (Ada_Version >= Ada_2005
13367 and then Is_Record_Type (Tagged_Type)
13368 and then Is_Tagged_Type (Tagged_Type)
13369 and then Has_Interfaces (Tagged_Type));
13371 -- Step 1: Transfer to the full-view primitives associated with the
13372 -- partial-view that cover interface primitives. Conceptually this
13373 -- work should be done later by Process_Full_View; done here to
13374 -- simplify its implementation at later stages. It can be safely
13375 -- done here because interfaces must be visible in the partial and
13376 -- private view (RM 7.3(7.3/2)).
13378 -- Small optimization: This work is only required if the parent may
13379 -- have entities whose Alias attribute reference an interface primitive.
13380 -- Such a situation may occur if the parent is an abstract type and the
13381 -- primitive has not been yet overridden or if the parent is a generic
13382 -- formal type covering interfaces.
13384 -- If the tagged type is not abstract, it cannot have abstract
13385 -- primitives (the only entities in the list of primitives of
13386 -- non-abstract tagged types that can reference abstract primitives
13387 -- through its Alias attribute are the internal entities that have
13388 -- attribute Interface_Alias, and these entities are generated later
13389 -- by Add_Internal_Interface_Entities).
13391 if In_Private_Part (Current_Scope)
13392 and then (Is_Abstract_Type (Parent_Type)
13394 Is_Generic_Type (Parent_Type))
13396 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
13397 while Present (Elmt) loop
13398 Subp := Node (Elmt);
13400 -- At this stage it is not possible to have entities in the list
13401 -- of primitives that have attribute Interface_Alias.
13403 pragma Assert (No (Interface_Alias (Subp)));
13405 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
13407 if Is_Interface (Typ) then
13408 E := Find_Primitive_Covering_Interface
13409 (Tagged_Type => Tagged_Type,
13410 Iface_Prim => Subp);
13413 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
13415 Replace_Elmt (Elmt, E);
13416 Remove_Homonym (Subp);
13424 -- Step 2: Add primitives of progenitors that are not implemented by
13425 -- parents of Tagged_Type.
13427 if Present (Interfaces (Base_Type (Tagged_Type))) then
13428 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
13429 while Present (Iface_Elmt) loop
13430 Iface := Node (Iface_Elmt);
13432 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
13433 while Present (Prim_Elmt) loop
13434 Iface_Subp := Node (Prim_Elmt);
13436 -- Exclude derivation of predefined primitives except those
13437 -- that come from source, or are inherited from one that comes
13438 -- from source. Required to catch declarations of equality
13439 -- operators of interfaces. For example:
13441 -- type Iface is interface;
13442 -- function "=" (Left, Right : Iface) return Boolean;
13444 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
13445 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
13447 E := Find_Primitive_Covering_Interface
13448 (Tagged_Type => Tagged_Type,
13449 Iface_Prim => Iface_Subp);
13451 -- If not found we derive a new primitive leaving its alias
13452 -- attribute referencing the interface primitive.
13456 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13458 -- Ada 2012 (AI05-0197): If the covering primitive's name
13459 -- differs from the name of the interface primitive then it
13460 -- is a private primitive inherited from a parent type. In
13461 -- such case, given that Tagged_Type covers the interface,
13462 -- the inherited private primitive becomes visible. For such
13463 -- purpose we add a new entity that renames the inherited
13464 -- private primitive.
13466 elsif Chars (E) /= Chars (Iface_Subp) then
13467 pragma Assert (Has_Suffix (E, 'P'));
13469 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13470 Set_Alias (New_Subp, E);
13471 Set_Is_Abstract_Subprogram (New_Subp,
13472 Is_Abstract_Subprogram (E));
13474 -- Propagate to the full view interface entities associated
13475 -- with the partial view.
13477 elsif In_Private_Part (Current_Scope)
13478 and then Present (Alias (E))
13479 and then Alias (E) = Iface_Subp
13481 List_Containing (Parent (E)) /=
13482 Private_Declarations
13484 (Unit_Declaration_Node (Current_Scope)))
13486 Append_Elmt (E, Primitive_Operations (Tagged_Type));
13490 Next_Elmt (Prim_Elmt);
13493 Next_Elmt (Iface_Elmt);
13496 end Derive_Progenitor_Subprograms;
13498 -----------------------
13499 -- Derive_Subprogram --
13500 -----------------------
13502 procedure Derive_Subprogram
13503 (New_Subp : in out Entity_Id;
13504 Parent_Subp : Entity_Id;
13505 Derived_Type : Entity_Id;
13506 Parent_Type : Entity_Id;
13507 Actual_Subp : Entity_Id := Empty)
13509 Formal : Entity_Id;
13510 -- Formal parameter of parent primitive operation
13512 Formal_Of_Actual : Entity_Id;
13513 -- Formal parameter of actual operation, when the derivation is to
13514 -- create a renaming for a primitive operation of an actual in an
13517 New_Formal : Entity_Id;
13518 -- Formal of inherited operation
13520 Visible_Subp : Entity_Id := Parent_Subp;
13522 function Is_Private_Overriding return Boolean;
13523 -- If Subp is a private overriding of a visible operation, the inherited
13524 -- operation derives from the overridden op (even though its body is the
13525 -- overriding one) and the inherited operation is visible now. See
13526 -- sem_disp to see the full details of the handling of the overridden
13527 -- subprogram, which is removed from the list of primitive operations of
13528 -- the type. The overridden subprogram is saved locally in Visible_Subp,
13529 -- and used to diagnose abstract operations that need overriding in the
13532 procedure Replace_Type (Id, New_Id : Entity_Id);
13533 -- When the type is an anonymous access type, create a new access type
13534 -- designating the derived type.
13536 procedure Set_Derived_Name;
13537 -- This procedure sets the appropriate Chars name for New_Subp. This
13538 -- is normally just a copy of the parent name. An exception arises for
13539 -- type support subprograms, where the name is changed to reflect the
13540 -- name of the derived type, e.g. if type foo is derived from type bar,
13541 -- then a procedure barDA is derived with a name fooDA.
13543 ---------------------------
13544 -- Is_Private_Overriding --
13545 ---------------------------
13547 function Is_Private_Overriding return Boolean is
13551 -- If the parent is not a dispatching operation there is no
13552 -- need to investigate overridings
13554 if not Is_Dispatching_Operation (Parent_Subp) then
13558 -- The visible operation that is overridden is a homonym of the
13559 -- parent subprogram. We scan the homonym chain to find the one
13560 -- whose alias is the subprogram we are deriving.
13562 Prev := Current_Entity (Parent_Subp);
13563 while Present (Prev) loop
13564 if Ekind (Prev) = Ekind (Parent_Subp)
13565 and then Alias (Prev) = Parent_Subp
13566 and then Scope (Parent_Subp) = Scope (Prev)
13567 and then not Is_Hidden (Prev)
13569 Visible_Subp := Prev;
13573 Prev := Homonym (Prev);
13577 end Is_Private_Overriding;
13583 procedure Replace_Type (Id, New_Id : Entity_Id) is
13584 Id_Type : constant Entity_Id := Etype (Id);
13585 Acc_Type : Entity_Id;
13586 Par : constant Node_Id := Parent (Derived_Type);
13589 -- When the type is an anonymous access type, create a new access
13590 -- type designating the derived type. This itype must be elaborated
13591 -- at the point of the derivation, not on subsequent calls that may
13592 -- be out of the proper scope for Gigi, so we insert a reference to
13593 -- it after the derivation.
13595 if Ekind (Id_Type) = E_Anonymous_Access_Type then
13597 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
13600 if Ekind (Desig_Typ) = E_Record_Type_With_Private
13601 and then Present (Full_View (Desig_Typ))
13602 and then not Is_Private_Type (Parent_Type)
13604 Desig_Typ := Full_View (Desig_Typ);
13607 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
13609 -- Ada 2005 (AI-251): Handle also derivations of abstract
13610 -- interface primitives.
13612 or else (Is_Interface (Desig_Typ)
13613 and then not Is_Class_Wide_Type (Desig_Typ))
13615 Acc_Type := New_Copy (Id_Type);
13616 Set_Etype (Acc_Type, Acc_Type);
13617 Set_Scope (Acc_Type, New_Subp);
13619 -- Set size of anonymous access type. If we have an access
13620 -- to an unconstrained array, this is a fat pointer, so it
13621 -- is sizes at twice addtress size.
13623 if Is_Array_Type (Desig_Typ)
13624 and then not Is_Constrained (Desig_Typ)
13626 Init_Size (Acc_Type, 2 * System_Address_Size);
13628 -- Other cases use a thin pointer
13631 Init_Size (Acc_Type, System_Address_Size);
13634 -- Set remaining characterstics of anonymous access type
13636 Init_Alignment (Acc_Type);
13637 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
13639 Set_Etype (New_Id, Acc_Type);
13640 Set_Scope (New_Id, New_Subp);
13642 -- Create a reference to it
13644 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
13647 Set_Etype (New_Id, Id_Type);
13651 -- In Ada2012, a formal may have an incomplete type but the type
13652 -- derivation that inherits the primitive follows the full view.
13654 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
13656 (Ekind (Id_Type) = E_Record_Type_With_Private
13657 and then Present (Full_View (Id_Type))
13659 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
13661 (Ada_Version >= Ada_2012
13662 and then Ekind (Id_Type) = E_Incomplete_Type
13663 and then Full_View (Id_Type) = Parent_Type)
13665 -- Constraint checks on formals are generated during expansion,
13666 -- based on the signature of the original subprogram. The bounds
13667 -- of the derived type are not relevant, and thus we can use
13668 -- the base type for the formals. However, the return type may be
13669 -- used in a context that requires that the proper static bounds
13670 -- be used (a case statement, for example) and for those cases
13671 -- we must use the derived type (first subtype), not its base.
13673 -- If the derived_type_definition has no constraints, we know that
13674 -- the derived type has the same constraints as the first subtype
13675 -- of the parent, and we can also use it rather than its base,
13676 -- which can lead to more efficient code.
13678 if Etype (Id) = Parent_Type then
13679 if Is_Scalar_Type (Parent_Type)
13681 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
13683 Set_Etype (New_Id, Derived_Type);
13685 elsif Nkind (Par) = N_Full_Type_Declaration
13687 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
13690 (Subtype_Indication (Type_Definition (Par)))
13692 Set_Etype (New_Id, Derived_Type);
13695 Set_Etype (New_Id, Base_Type (Derived_Type));
13699 Set_Etype (New_Id, Base_Type (Derived_Type));
13703 Set_Etype (New_Id, Etype (Id));
13707 ----------------------
13708 -- Set_Derived_Name --
13709 ----------------------
13711 procedure Set_Derived_Name is
13712 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13714 if Nm = TSS_Null then
13715 Set_Chars (New_Subp, Chars (Parent_Subp));
13717 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13719 end Set_Derived_Name;
13721 -- Start of processing for Derive_Subprogram
13725 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13726 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13727 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
13729 -- Check whether the inherited subprogram is a private operation that
13730 -- should be inherited but not yet made visible. Such subprograms can
13731 -- become visible at a later point (e.g., the private part of a public
13732 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13733 -- following predicate is true, then this is not such a private
13734 -- operation and the subprogram simply inherits the name of the parent
13735 -- subprogram. Note the special check for the names of controlled
13736 -- operations, which are currently exempted from being inherited with
13737 -- a hidden name because they must be findable for generation of
13738 -- implicit run-time calls.
13740 if not Is_Hidden (Parent_Subp)
13741 or else Is_Internal (Parent_Subp)
13742 or else Is_Private_Overriding
13743 or else Is_Internal_Name (Chars (Parent_Subp))
13744 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
13750 -- An inherited dispatching equality will be overridden by an internally
13751 -- generated one, or by an explicit one, so preserve its name and thus
13752 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13753 -- private operation it may become invisible if the full view has
13754 -- progenitors, and the dispatch table will be malformed.
13755 -- We check that the type is limited to handle the anomalous declaration
13756 -- of Limited_Controlled, which is derived from a non-limited type, and
13757 -- which is handled specially elsewhere as well.
13759 elsif Chars (Parent_Subp) = Name_Op_Eq
13760 and then Is_Dispatching_Operation (Parent_Subp)
13761 and then Etype (Parent_Subp) = Standard_Boolean
13762 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13764 Etype (First_Formal (Parent_Subp)) =
13765 Etype (Next_Formal (First_Formal (Parent_Subp)))
13769 -- If parent is hidden, this can be a regular derivation if the
13770 -- parent is immediately visible in a non-instantiating context,
13771 -- or if we are in the private part of an instance. This test
13772 -- should still be refined ???
13774 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13775 -- operation as a non-visible operation in cases where the parent
13776 -- subprogram might not be visible now, but was visible within the
13777 -- original generic, so it would be wrong to make the inherited
13778 -- subprogram non-visible now. (Not clear if this test is fully
13779 -- correct; are there any cases where we should declare the inherited
13780 -- operation as not visible to avoid it being overridden, e.g., when
13781 -- the parent type is a generic actual with private primitives ???)
13783 -- (they should be treated the same as other private inherited
13784 -- subprograms, but it's not clear how to do this cleanly). ???
13786 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13787 and then Is_Immediately_Visible (Parent_Subp)
13788 and then not In_Instance)
13789 or else In_Instance_Not_Visible
13793 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13794 -- overrides an interface primitive because interface primitives
13795 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13797 elsif Ada_Version >= Ada_2005
13798 and then Is_Dispatching_Operation (Parent_Subp)
13799 and then Covers_Some_Interface (Parent_Subp)
13803 -- Otherwise, the type is inheriting a private operation, so enter
13804 -- it with a special name so it can't be overridden.
13807 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13810 Set_Parent (New_Subp, Parent (Derived_Type));
13812 if Present (Actual_Subp) then
13813 Replace_Type (Actual_Subp, New_Subp);
13815 Replace_Type (Parent_Subp, New_Subp);
13818 Conditional_Delay (New_Subp, Parent_Subp);
13820 -- If we are creating a renaming for a primitive operation of an
13821 -- actual of a generic derived type, we must examine the signature
13822 -- of the actual primitive, not that of the generic formal, which for
13823 -- example may be an interface. However the name and initial value
13824 -- of the inherited operation are those of the formal primitive.
13826 Formal := First_Formal (Parent_Subp);
13828 if Present (Actual_Subp) then
13829 Formal_Of_Actual := First_Formal (Actual_Subp);
13831 Formal_Of_Actual := Empty;
13834 while Present (Formal) loop
13835 New_Formal := New_Copy (Formal);
13837 -- Normally we do not go copying parents, but in the case of
13838 -- formals, we need to link up to the declaration (which is the
13839 -- parameter specification), and it is fine to link up to the
13840 -- original formal's parameter specification in this case.
13842 Set_Parent (New_Formal, Parent (Formal));
13843 Append_Entity (New_Formal, New_Subp);
13845 if Present (Formal_Of_Actual) then
13846 Replace_Type (Formal_Of_Actual, New_Formal);
13847 Next_Formal (Formal_Of_Actual);
13849 Replace_Type (Formal, New_Formal);
13852 Next_Formal (Formal);
13855 -- If this derivation corresponds to a tagged generic actual, then
13856 -- primitive operations rename those of the actual. Otherwise the
13857 -- primitive operations rename those of the parent type, If the parent
13858 -- renames an intrinsic operator, so does the new subprogram. We except
13859 -- concatenation, which is always properly typed, and does not get
13860 -- expanded as other intrinsic operations.
13862 if No (Actual_Subp) then
13863 if Is_Intrinsic_Subprogram (Parent_Subp) then
13864 Set_Is_Intrinsic_Subprogram (New_Subp);
13866 if Present (Alias (Parent_Subp))
13867 and then Chars (Parent_Subp) /= Name_Op_Concat
13869 Set_Alias (New_Subp, Alias (Parent_Subp));
13871 Set_Alias (New_Subp, Parent_Subp);
13875 Set_Alias (New_Subp, Parent_Subp);
13879 Set_Alias (New_Subp, Actual_Subp);
13882 -- Derived subprograms of a tagged type must inherit the convention
13883 -- of the parent subprogram (a requirement of AI-117). Derived
13884 -- subprograms of untagged types simply get convention Ada by default.
13886 -- If the derived type is a tagged generic formal type with unknown
13887 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
13889 -- However, if the type is derived from a generic formal, the further
13890 -- inherited subprogram has the convention of the non-generic ancestor.
13891 -- Otherwise there would be no way to override the operation.
13892 -- (This is subject to forthcoming ARG discussions).
13894 if Is_Tagged_Type (Derived_Type) then
13895 if Is_Generic_Type (Derived_Type)
13896 and then Has_Unknown_Discriminants (Derived_Type)
13898 Set_Convention (New_Subp, Convention_Intrinsic);
13901 if Is_Generic_Type (Parent_Type)
13902 and then Has_Unknown_Discriminants (Parent_Type)
13904 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
13906 Set_Convention (New_Subp, Convention (Parent_Subp));
13911 -- Predefined controlled operations retain their name even if the parent
13912 -- is hidden (see above), but they are not primitive operations if the
13913 -- ancestor is not visible, for example if the parent is a private
13914 -- extension completed with a controlled extension. Note that a full
13915 -- type that is controlled can break privacy: the flag Is_Controlled is
13916 -- set on both views of the type.
13918 if Is_Controlled (Parent_Type)
13919 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
13922 and then Is_Hidden (Parent_Subp)
13923 and then not Is_Visibly_Controlled (Parent_Type)
13925 Set_Is_Hidden (New_Subp);
13928 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13929 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13931 if Ekind (Parent_Subp) = E_Procedure then
13932 Set_Is_Valued_Procedure
13933 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13935 Set_Has_Controlling_Result
13936 (New_Subp, Has_Controlling_Result (Parent_Subp));
13939 -- No_Return must be inherited properly. If this is overridden in the
13940 -- case of a dispatching operation, then a check is made in Sem_Disp
13941 -- that the overriding operation is also No_Return (no such check is
13942 -- required for the case of non-dispatching operation.
13944 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13946 -- A derived function with a controlling result is abstract. If the
13947 -- Derived_Type is a nonabstract formal generic derived type, then
13948 -- inherited operations are not abstract: the required check is done at
13949 -- instantiation time. If the derivation is for a generic actual, the
13950 -- function is not abstract unless the actual is.
13952 if Is_Generic_Type (Derived_Type)
13953 and then not Is_Abstract_Type (Derived_Type)
13957 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13958 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13960 elsif Ada_Version >= Ada_2005
13961 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13962 or else (Is_Tagged_Type (Derived_Type)
13963 and then Etype (New_Subp) = Derived_Type
13964 and then not Is_Null_Extension (Derived_Type))
13965 or else (Is_Tagged_Type (Derived_Type)
13966 and then Ekind (Etype (New_Subp)) =
13967 E_Anonymous_Access_Type
13968 and then Designated_Type (Etype (New_Subp)) =
13970 and then not Is_Null_Extension (Derived_Type)))
13971 and then No (Actual_Subp)
13973 if not Is_Tagged_Type (Derived_Type)
13974 or else Is_Abstract_Type (Derived_Type)
13975 or else Is_Abstract_Subprogram (Alias (New_Subp))
13977 Set_Is_Abstract_Subprogram (New_Subp);
13979 Set_Requires_Overriding (New_Subp);
13982 elsif Ada_Version < Ada_2005
13983 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13984 or else (Is_Tagged_Type (Derived_Type)
13985 and then Etype (New_Subp) = Derived_Type
13986 and then No (Actual_Subp)))
13988 Set_Is_Abstract_Subprogram (New_Subp);
13990 -- AI05-0097 : an inherited operation that dispatches on result is
13991 -- abstract if the derived type is abstract, even if the parent type
13992 -- is concrete and the derived type is a null extension.
13994 elsif Has_Controlling_Result (Alias (New_Subp))
13995 and then Is_Abstract_Type (Etype (New_Subp))
13997 Set_Is_Abstract_Subprogram (New_Subp);
13999 -- Finally, if the parent type is abstract we must verify that all
14000 -- inherited operations are either non-abstract or overridden, or that
14001 -- the derived type itself is abstract (this check is performed at the
14002 -- end of a package declaration, in Check_Abstract_Overriding). A
14003 -- private overriding in the parent type will not be visible in the
14004 -- derivation if we are not in an inner package or in a child unit of
14005 -- the parent type, in which case the abstractness of the inherited
14006 -- operation is carried to the new subprogram.
14008 elsif Is_Abstract_Type (Parent_Type)
14009 and then not In_Open_Scopes (Scope (Parent_Type))
14010 and then Is_Private_Overriding
14011 and then Is_Abstract_Subprogram (Visible_Subp)
14013 if No (Actual_Subp) then
14014 Set_Alias (New_Subp, Visible_Subp);
14015 Set_Is_Abstract_Subprogram (New_Subp, True);
14018 -- If this is a derivation for an instance of a formal derived
14019 -- type, abstractness comes from the primitive operation of the
14020 -- actual, not from the operation inherited from the ancestor.
14022 Set_Is_Abstract_Subprogram
14023 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14027 New_Overloaded_Entity (New_Subp, Derived_Type);
14029 -- Check for case of a derived subprogram for the instantiation of a
14030 -- formal derived tagged type, if so mark the subprogram as dispatching
14031 -- and inherit the dispatching attributes of the actual subprogram. The
14032 -- derived subprogram is effectively renaming of the actual subprogram,
14033 -- so it needs to have the same attributes as the actual.
14035 if Present (Actual_Subp)
14036 and then Is_Dispatching_Operation (Actual_Subp)
14038 Set_Is_Dispatching_Operation (New_Subp);
14040 if Present (DTC_Entity (Actual_Subp)) then
14041 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14042 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
14046 -- Indicate that a derived subprogram does not require a body and that
14047 -- it does not require processing of default expressions.
14049 Set_Has_Completion (New_Subp);
14050 Set_Default_Expressions_Processed (New_Subp);
14052 if Ekind (New_Subp) = E_Function then
14053 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14055 end Derive_Subprogram;
14057 ------------------------
14058 -- Derive_Subprograms --
14059 ------------------------
14061 procedure Derive_Subprograms
14062 (Parent_Type : Entity_Id;
14063 Derived_Type : Entity_Id;
14064 Generic_Actual : Entity_Id := Empty)
14066 Op_List : constant Elist_Id :=
14067 Collect_Primitive_Operations (Parent_Type);
14069 function Check_Derived_Type return Boolean;
14070 -- Check that all the entities derived from Parent_Type are found in
14071 -- the list of primitives of Derived_Type exactly in the same order.
14073 procedure Derive_Interface_Subprogram
14074 (New_Subp : in out Entity_Id;
14076 Actual_Subp : Entity_Id);
14077 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14078 -- (which is an interface primitive). If Generic_Actual is present then
14079 -- Actual_Subp is the actual subprogram corresponding with the generic
14080 -- subprogram Subp.
14082 function Check_Derived_Type return Boolean is
14086 New_Subp : Entity_Id;
14091 -- Traverse list of entities in the current scope searching for
14092 -- an incomplete type whose full-view is derived type
14094 E := First_Entity (Scope (Derived_Type));
14095 while Present (E) and then E /= Derived_Type loop
14096 if Ekind (E) = E_Incomplete_Type
14097 and then Present (Full_View (E))
14098 and then Full_View (E) = Derived_Type
14100 -- Disable this test if Derived_Type completes an incomplete
14101 -- type because in such case more primitives can be added
14102 -- later to the list of primitives of Derived_Type by routine
14103 -- Process_Incomplete_Dependents
14108 E := Next_Entity (E);
14111 List := Collect_Primitive_Operations (Derived_Type);
14112 Elmt := First_Elmt (List);
14114 Op_Elmt := First_Elmt (Op_List);
14115 while Present (Op_Elmt) loop
14116 Subp := Node (Op_Elmt);
14117 New_Subp := Node (Elmt);
14119 -- At this early stage Derived_Type has no entities with attribute
14120 -- Interface_Alias. In addition, such primitives are always
14121 -- located at the end of the list of primitives of Parent_Type.
14122 -- Therefore, if found we can safely stop processing pending
14125 exit when Present (Interface_Alias (Subp));
14127 -- Handle hidden entities
14129 if not Is_Predefined_Dispatching_Operation (Subp)
14130 and then Is_Hidden (Subp)
14132 if Present (New_Subp)
14133 and then Primitive_Names_Match (Subp, New_Subp)
14139 if not Present (New_Subp)
14140 or else Ekind (Subp) /= Ekind (New_Subp)
14141 or else not Primitive_Names_Match (Subp, New_Subp)
14149 Next_Elmt (Op_Elmt);
14153 end Check_Derived_Type;
14155 ---------------------------------
14156 -- Derive_Interface_Subprogram --
14157 ---------------------------------
14159 procedure Derive_Interface_Subprogram
14160 (New_Subp : in out Entity_Id;
14162 Actual_Subp : Entity_Id)
14164 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14165 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14168 pragma Assert (Is_Interface (Iface_Type));
14171 (New_Subp => New_Subp,
14172 Parent_Subp => Iface_Subp,
14173 Derived_Type => Derived_Type,
14174 Parent_Type => Iface_Type,
14175 Actual_Subp => Actual_Subp);
14177 -- Given that this new interface entity corresponds with a primitive
14178 -- of the parent that was not overridden we must leave it associated
14179 -- with its parent primitive to ensure that it will share the same
14180 -- dispatch table slot when overridden.
14182 if No (Actual_Subp) then
14183 Set_Alias (New_Subp, Subp);
14185 -- For instantiations this is not needed since the previous call to
14186 -- Derive_Subprogram leaves the entity well decorated.
14189 pragma Assert (Alias (New_Subp) = Actual_Subp);
14192 end Derive_Interface_Subprogram;
14196 Alias_Subp : Entity_Id;
14197 Act_List : Elist_Id;
14198 Act_Elmt : Elmt_Id;
14199 Act_Subp : Entity_Id := Empty;
14201 Need_Search : Boolean := False;
14202 New_Subp : Entity_Id := Empty;
14203 Parent_Base : Entity_Id;
14206 -- Start of processing for Derive_Subprograms
14209 if Ekind (Parent_Type) = E_Record_Type_With_Private
14210 and then Has_Discriminants (Parent_Type)
14211 and then Present (Full_View (Parent_Type))
14213 Parent_Base := Full_View (Parent_Type);
14215 Parent_Base := Parent_Type;
14218 if Present (Generic_Actual) then
14219 Act_List := Collect_Primitive_Operations (Generic_Actual);
14220 Act_Elmt := First_Elmt (Act_List);
14222 Act_List := No_Elist;
14223 Act_Elmt := No_Elmt;
14226 -- Derive primitives inherited from the parent. Note that if the generic
14227 -- actual is present, this is not really a type derivation, it is a
14228 -- completion within an instance.
14230 -- Case 1: Derived_Type does not implement interfaces
14232 if not Is_Tagged_Type (Derived_Type)
14233 or else (not Has_Interfaces (Derived_Type)
14234 and then not (Present (Generic_Actual)
14235 and then Has_Interfaces (Generic_Actual)))
14237 Elmt := First_Elmt (Op_List);
14238 while Present (Elmt) loop
14239 Subp := Node (Elmt);
14241 -- Literals are derived earlier in the process of building the
14242 -- derived type, and are skipped here.
14244 if Ekind (Subp) = E_Enumeration_Literal then
14247 -- The actual is a direct descendant and the common primitive
14248 -- operations appear in the same order.
14250 -- If the generic parent type is present, the derived type is an
14251 -- instance of a formal derived type, and within the instance its
14252 -- operations are those of the actual. We derive from the formal
14253 -- type but make the inherited operations aliases of the
14254 -- corresponding operations of the actual.
14257 pragma Assert (No (Node (Act_Elmt))
14258 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
14261 (Subp, Node (Act_Elmt),
14262 Skip_Controlling_Formals => True)));
14265 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
14267 if Present (Act_Elmt) then
14268 Next_Elmt (Act_Elmt);
14275 -- Case 2: Derived_Type implements interfaces
14278 -- If the parent type has no predefined primitives we remove
14279 -- predefined primitives from the list of primitives of generic
14280 -- actual to simplify the complexity of this algorithm.
14282 if Present (Generic_Actual) then
14284 Has_Predefined_Primitives : Boolean := False;
14287 -- Check if the parent type has predefined primitives
14289 Elmt := First_Elmt (Op_List);
14290 while Present (Elmt) loop
14291 Subp := Node (Elmt);
14293 if Is_Predefined_Dispatching_Operation (Subp)
14294 and then not Comes_From_Source (Ultimate_Alias (Subp))
14296 Has_Predefined_Primitives := True;
14303 -- Remove predefined primitives of Generic_Actual. We must use
14304 -- an auxiliary list because in case of tagged types the value
14305 -- returned by Collect_Primitive_Operations is the value stored
14306 -- in its Primitive_Operations attribute (and we don't want to
14307 -- modify its current contents).
14309 if not Has_Predefined_Primitives then
14311 Aux_List : constant Elist_Id := New_Elmt_List;
14314 Elmt := First_Elmt (Act_List);
14315 while Present (Elmt) loop
14316 Subp := Node (Elmt);
14318 if not Is_Predefined_Dispatching_Operation (Subp)
14319 or else Comes_From_Source (Subp)
14321 Append_Elmt (Subp, Aux_List);
14327 Act_List := Aux_List;
14331 Act_Elmt := First_Elmt (Act_List);
14332 Act_Subp := Node (Act_Elmt);
14336 -- Stage 1: If the generic actual is not present we derive the
14337 -- primitives inherited from the parent type. If the generic parent
14338 -- type is present, the derived type is an instance of a formal
14339 -- derived type, and within the instance its operations are those of
14340 -- the actual. We derive from the formal type but make the inherited
14341 -- operations aliases of the corresponding operations of the actual.
14343 Elmt := First_Elmt (Op_List);
14344 while Present (Elmt) loop
14345 Subp := Node (Elmt);
14346 Alias_Subp := Ultimate_Alias (Subp);
14348 -- Do not derive internal entities of the parent that link
14349 -- interface primitives with their covering primitive. These
14350 -- entities will be added to this type when frozen.
14352 if Present (Interface_Alias (Subp)) then
14356 -- If the generic actual is present find the corresponding
14357 -- operation in the generic actual. If the parent type is a
14358 -- direct ancestor of the derived type then, even if it is an
14359 -- interface, the operations are inherited from the primary
14360 -- dispatch table and are in the proper order. If we detect here
14361 -- that primitives are not in the same order we traverse the list
14362 -- of primitive operations of the actual to find the one that
14363 -- implements the interface primitive.
14367 (Present (Generic_Actual)
14368 and then Present (Act_Subp)
14370 (Primitive_Names_Match (Subp, Act_Subp)
14372 Type_Conformant (Subp, Act_Subp,
14373 Skip_Controlling_Formals => True)))
14375 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
14376 Use_Full_View => True));
14378 -- Remember that we need searching for all pending primitives
14380 Need_Search := True;
14382 -- Handle entities associated with interface primitives
14384 if Present (Alias_Subp)
14385 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14386 and then not Is_Predefined_Dispatching_Operation (Subp)
14388 -- Search for the primitive in the homonym chain
14391 Find_Primitive_Covering_Interface
14392 (Tagged_Type => Generic_Actual,
14393 Iface_Prim => Alias_Subp);
14395 -- Previous search may not locate primitives covering
14396 -- interfaces defined in generics units or instantiations.
14397 -- (it fails if the covering primitive has formals whose
14398 -- type is also defined in generics or instantiations).
14399 -- In such case we search in the list of primitives of the
14400 -- generic actual for the internal entity that links the
14401 -- interface primitive and the covering primitive.
14404 and then Is_Generic_Type (Parent_Type)
14406 -- This code has been designed to handle only generic
14407 -- formals that implement interfaces that are defined
14408 -- in a generic unit or instantiation. If this code is
14409 -- needed for other cases we must review it because
14410 -- (given that it relies on Original_Location to locate
14411 -- the primitive of Generic_Actual that covers the
14412 -- interface) it could leave linked through attribute
14413 -- Alias entities of unrelated instantiations).
14417 (Scope (Find_Dispatching_Type (Alias_Subp)))
14419 Instantiation_Depth
14420 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
14423 Iface_Prim_Loc : constant Source_Ptr :=
14424 Original_Location (Sloc (Alias_Subp));
14431 First_Elmt (Primitive_Operations (Generic_Actual));
14433 Search : while Present (Elmt) loop
14434 Prim := Node (Elmt);
14436 if Present (Interface_Alias (Prim))
14437 and then Original_Location
14438 (Sloc (Interface_Alias (Prim))) =
14441 Act_Subp := Alias (Prim);
14450 pragma Assert (Present (Act_Subp)
14451 or else Is_Abstract_Type (Generic_Actual)
14452 or else Serious_Errors_Detected > 0);
14454 -- Handle predefined primitives plus the rest of user-defined
14458 Act_Elmt := First_Elmt (Act_List);
14459 while Present (Act_Elmt) loop
14460 Act_Subp := Node (Act_Elmt);
14462 exit when Primitive_Names_Match (Subp, Act_Subp)
14463 and then Type_Conformant
14465 Skip_Controlling_Formals => True)
14466 and then No (Interface_Alias (Act_Subp));
14468 Next_Elmt (Act_Elmt);
14471 if No (Act_Elmt) then
14477 -- Case 1: If the parent is a limited interface then it has the
14478 -- predefined primitives of synchronized interfaces. However, the
14479 -- actual type may be a non-limited type and hence it does not
14480 -- have such primitives.
14482 if Present (Generic_Actual)
14483 and then not Present (Act_Subp)
14484 and then Is_Limited_Interface (Parent_Base)
14485 and then Is_Predefined_Interface_Primitive (Subp)
14489 -- Case 2: Inherit entities associated with interfaces that were
14490 -- not covered by the parent type. We exclude here null interface
14491 -- primitives because they do not need special management.
14493 -- We also exclude interface operations that are renamings. If the
14494 -- subprogram is an explicit renaming of an interface primitive,
14495 -- it is a regular primitive operation, and the presence of its
14496 -- alias is not relevant: it has to be derived like any other
14499 elsif Present (Alias (Subp))
14500 and then Nkind (Unit_Declaration_Node (Subp)) /=
14501 N_Subprogram_Renaming_Declaration
14502 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14504 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
14505 and then Null_Present (Parent (Alias_Subp)))
14507 -- If this is an abstract private type then we transfer the
14508 -- derivation of the interface primitive from the partial view
14509 -- to the full view. This is safe because all the interfaces
14510 -- must be visible in the partial view. Done to avoid adding
14511 -- a new interface derivation to the private part of the
14512 -- enclosing package; otherwise this new derivation would be
14513 -- decorated as hidden when the analysis of the enclosing
14514 -- package completes.
14516 if Is_Abstract_Type (Derived_Type)
14517 and then In_Private_Part (Current_Scope)
14518 and then Has_Private_Declaration (Derived_Type)
14521 Partial_View : Entity_Id;
14526 Partial_View := First_Entity (Current_Scope);
14528 exit when No (Partial_View)
14529 or else (Has_Private_Declaration (Partial_View)
14531 Full_View (Partial_View) = Derived_Type);
14533 Next_Entity (Partial_View);
14536 -- If the partial view was not found then the source code
14537 -- has errors and the derivation is not needed.
14539 if Present (Partial_View) then
14541 First_Elmt (Primitive_Operations (Partial_View));
14542 while Present (Elmt) loop
14543 Ent := Node (Elmt);
14545 if Present (Alias (Ent))
14546 and then Ultimate_Alias (Ent) = Alias (Subp)
14549 (Ent, Primitive_Operations (Derived_Type));
14556 -- If the interface primitive was not found in the
14557 -- partial view then this interface primitive was
14558 -- overridden. We add a derivation to activate in
14559 -- Derive_Progenitor_Subprograms the machinery to
14563 Derive_Interface_Subprogram
14564 (New_Subp => New_Subp,
14566 Actual_Subp => Act_Subp);
14571 Derive_Interface_Subprogram
14572 (New_Subp => New_Subp,
14574 Actual_Subp => Act_Subp);
14577 -- Case 3: Common derivation
14581 (New_Subp => New_Subp,
14582 Parent_Subp => Subp,
14583 Derived_Type => Derived_Type,
14584 Parent_Type => Parent_Base,
14585 Actual_Subp => Act_Subp);
14588 -- No need to update Act_Elm if we must search for the
14589 -- corresponding operation in the generic actual
14592 and then Present (Act_Elmt)
14594 Next_Elmt (Act_Elmt);
14595 Act_Subp := Node (Act_Elmt);
14602 -- Inherit additional operations from progenitors. If the derived
14603 -- type is a generic actual, there are not new primitive operations
14604 -- for the type because it has those of the actual, and therefore
14605 -- nothing needs to be done. The renamings generated above are not
14606 -- primitive operations, and their purpose is simply to make the
14607 -- proper operations visible within an instantiation.
14609 if No (Generic_Actual) then
14610 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
14614 -- Final check: Direct descendants must have their primitives in the
14615 -- same order. We exclude from this test untagged types and instances
14616 -- of formal derived types. We skip this test if we have already
14617 -- reported serious errors in the sources.
14619 pragma Assert (not Is_Tagged_Type (Derived_Type)
14620 or else Present (Generic_Actual)
14621 or else Serious_Errors_Detected > 0
14622 or else Check_Derived_Type);
14623 end Derive_Subprograms;
14625 --------------------------------
14626 -- Derived_Standard_Character --
14627 --------------------------------
14629 procedure Derived_Standard_Character
14631 Parent_Type : Entity_Id;
14632 Derived_Type : Entity_Id)
14634 Loc : constant Source_Ptr := Sloc (N);
14635 Def : constant Node_Id := Type_Definition (N);
14636 Indic : constant Node_Id := Subtype_Indication (Def);
14637 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
14638 Implicit_Base : constant Entity_Id :=
14640 (E_Enumeration_Type, N, Derived_Type, 'B');
14646 Discard_Node (Process_Subtype (Indic, N));
14648 Set_Etype (Implicit_Base, Parent_Base);
14649 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
14650 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
14652 Set_Is_Character_Type (Implicit_Base, True);
14653 Set_Has_Delayed_Freeze (Implicit_Base);
14655 -- The bounds of the implicit base are the bounds of the parent base.
14656 -- Note that their type is the parent base.
14658 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
14659 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
14661 Set_Scalar_Range (Implicit_Base,
14664 High_Bound => Hi));
14666 Conditional_Delay (Derived_Type, Parent_Type);
14668 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
14669 Set_Etype (Derived_Type, Implicit_Base);
14670 Set_Size_Info (Derived_Type, Parent_Type);
14672 if Unknown_RM_Size (Derived_Type) then
14673 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
14676 Set_Is_Character_Type (Derived_Type, True);
14678 if Nkind (Indic) /= N_Subtype_Indication then
14680 -- If no explicit constraint, the bounds are those
14681 -- of the parent type.
14683 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
14684 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
14685 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
14688 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
14690 -- Because the implicit base is used in the conversion of the bounds, we
14691 -- have to freeze it now. This is similar to what is done for numeric
14692 -- types, and it equally suspicious, but otherwise a non-static bound
14693 -- will have a reference to an unfrozen type, which is rejected by Gigi
14694 -- (???). This requires specific care for definition of stream
14695 -- attributes. For details, see comments at the end of
14696 -- Build_Derived_Numeric_Type.
14698 Freeze_Before (N, Implicit_Base);
14699 end Derived_Standard_Character;
14701 ------------------------------
14702 -- Derived_Type_Declaration --
14703 ------------------------------
14705 procedure Derived_Type_Declaration
14708 Is_Completion : Boolean)
14710 Parent_Type : Entity_Id;
14712 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
14713 -- Check whether the parent type is a generic formal, or derives
14714 -- directly or indirectly from one.
14716 ------------------------
14717 -- Comes_From_Generic --
14718 ------------------------
14720 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
14722 if Is_Generic_Type (Typ) then
14725 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14728 elsif Is_Private_Type (Typ)
14729 and then Present (Full_View (Typ))
14730 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14734 elsif Is_Generic_Actual_Type (Typ) then
14740 end Comes_From_Generic;
14744 Def : constant Node_Id := Type_Definition (N);
14745 Iface_Def : Node_Id;
14746 Indic : constant Node_Id := Subtype_Indication (Def);
14747 Extension : constant Node_Id := Record_Extension_Part (Def);
14748 Parent_Node : Node_Id;
14751 -- Start of processing for Derived_Type_Declaration
14754 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14756 -- Ada 2005 (AI-251): In case of interface derivation check that the
14757 -- parent is also an interface.
14759 if Interface_Present (Def) then
14760 Check_SPARK_Restriction ("interface is not allowed", Def);
14762 if not Is_Interface (Parent_Type) then
14763 Diagnose_Interface (Indic, Parent_Type);
14766 Parent_Node := Parent (Base_Type (Parent_Type));
14767 Iface_Def := Type_Definition (Parent_Node);
14769 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14770 -- other limited interfaces.
14772 if Limited_Present (Def) then
14773 if Limited_Present (Iface_Def) then
14776 elsif Protected_Present (Iface_Def) then
14778 ("descendant of& must be declared"
14779 & " as a protected interface",
14782 elsif Synchronized_Present (Iface_Def) then
14784 ("descendant of& must be declared"
14785 & " as a synchronized interface",
14788 elsif Task_Present (Iface_Def) then
14790 ("descendant of& must be declared as a task interface",
14795 ("(Ada 2005) limited interface cannot "
14796 & "inherit from non-limited interface", Indic);
14799 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14800 -- from non-limited or limited interfaces.
14802 elsif not Protected_Present (Def)
14803 and then not Synchronized_Present (Def)
14804 and then not Task_Present (Def)
14806 if Limited_Present (Iface_Def) then
14809 elsif Protected_Present (Iface_Def) then
14811 ("descendant of& must be declared"
14812 & " as a protected interface",
14815 elsif Synchronized_Present (Iface_Def) then
14817 ("descendant of& must be declared"
14818 & " as a synchronized interface",
14821 elsif Task_Present (Iface_Def) then
14823 ("descendant of& must be declared as a task interface",
14832 if Is_Tagged_Type (Parent_Type)
14833 and then Is_Concurrent_Type (Parent_Type)
14834 and then not Is_Interface (Parent_Type)
14837 ("parent type of a record extension cannot be "
14838 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14839 Set_Etype (T, Any_Type);
14843 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14846 if Is_Tagged_Type (Parent_Type)
14847 and then Is_Non_Empty_List (Interface_List (Def))
14854 Intf := First (Interface_List (Def));
14855 while Present (Intf) loop
14856 T := Find_Type_Of_Subtype_Indic (Intf);
14858 if not Is_Interface (T) then
14859 Diagnose_Interface (Intf, T);
14861 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14862 -- a limited type from having a nonlimited progenitor.
14864 elsif (Limited_Present (Def)
14865 or else (not Is_Interface (Parent_Type)
14866 and then Is_Limited_Type (Parent_Type)))
14867 and then not Is_Limited_Interface (T)
14870 ("progenitor interface& of limited type must be limited",
14879 if Parent_Type = Any_Type
14880 or else Etype (Parent_Type) = Any_Type
14881 or else (Is_Class_Wide_Type (Parent_Type)
14882 and then Etype (Parent_Type) = T)
14884 -- If Parent_Type is undefined or illegal, make new type into a
14885 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14886 -- errors. If this is a self-definition, emit error now.
14889 or else T = Etype (Parent_Type)
14891 Error_Msg_N ("type cannot be used in its own definition", Indic);
14894 Set_Ekind (T, Ekind (Parent_Type));
14895 Set_Etype (T, Any_Type);
14896 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14898 if Is_Tagged_Type (T)
14899 and then Is_Record_Type (T)
14901 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14907 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14908 -- an interface is special because the list of interfaces in the full
14909 -- view can be given in any order. For example:
14911 -- type A is interface;
14912 -- type B is interface and A;
14913 -- type D is new B with private;
14915 -- type D is new A and B with null record; -- 1 --
14917 -- In this case we perform the following transformation of -1-:
14919 -- type D is new B and A with null record;
14921 -- If the parent of the full-view covers the parent of the partial-view
14922 -- we have two possible cases:
14924 -- 1) They have the same parent
14925 -- 2) The parent of the full-view implements some further interfaces
14927 -- In both cases we do not need to perform the transformation. In the
14928 -- first case the source program is correct and the transformation is
14929 -- not needed; in the second case the source program does not fulfill
14930 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14933 -- This transformation not only simplifies the rest of the analysis of
14934 -- this type declaration but also simplifies the correct generation of
14935 -- the object layout to the expander.
14937 if In_Private_Part (Current_Scope)
14938 and then Is_Interface (Parent_Type)
14942 Partial_View : Entity_Id;
14943 Partial_View_Parent : Entity_Id;
14944 New_Iface : Node_Id;
14947 -- Look for the associated private type declaration
14949 Partial_View := First_Entity (Current_Scope);
14951 exit when No (Partial_View)
14952 or else (Has_Private_Declaration (Partial_View)
14953 and then Full_View (Partial_View) = T);
14955 Next_Entity (Partial_View);
14958 -- If the partial view was not found then the source code has
14959 -- errors and the transformation is not needed.
14961 if Present (Partial_View) then
14962 Partial_View_Parent := Etype (Partial_View);
14964 -- If the parent of the full-view covers the parent of the
14965 -- partial-view we have nothing else to do.
14967 if Interface_Present_In_Ancestor
14968 (Parent_Type, Partial_View_Parent)
14972 -- Traverse the list of interfaces of the full-view to look
14973 -- for the parent of the partial-view and perform the tree
14977 Iface := First (Interface_List (Def));
14978 while Present (Iface) loop
14979 if Etype (Iface) = Etype (Partial_View) then
14980 Rewrite (Subtype_Indication (Def),
14981 New_Copy (Subtype_Indication
14982 (Parent (Partial_View))));
14985 Make_Identifier (Sloc (N), Chars (Parent_Type));
14986 Append (New_Iface, Interface_List (Def));
14988 -- Analyze the transformed code
14990 Derived_Type_Declaration (T, N, Is_Completion);
15001 -- Only composite types other than array types are allowed to have
15002 -- discriminants. In SPARK, no types are allowed to have discriminants.
15004 if Present (Discriminant_Specifications (N)) then
15005 if (Is_Elementary_Type (Parent_Type)
15006 or else Is_Array_Type (Parent_Type))
15007 and then not Error_Posted (N)
15010 ("elementary or array type cannot have discriminants",
15011 Defining_Identifier (First (Discriminant_Specifications (N))));
15012 Set_Has_Discriminants (T, False);
15014 Check_SPARK_Restriction ("discriminant type is not allowed", N);
15018 -- In Ada 83, a derived type defined in a package specification cannot
15019 -- be used for further derivation until the end of its visible part.
15020 -- Note that derivation in the private part of the package is allowed.
15022 if Ada_Version = Ada_83
15023 and then Is_Derived_Type (Parent_Type)
15024 and then In_Visible_Part (Scope (Parent_Type))
15026 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15028 ("(Ada 83): premature use of type for derivation", Indic);
15032 -- Check for early use of incomplete or private type
15034 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15035 Error_Msg_N ("premature derivation of incomplete type", Indic);
15038 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15039 and then not Comes_From_Generic (Parent_Type))
15040 or else Has_Private_Component (Parent_Type)
15042 -- The ancestor type of a formal type can be incomplete, in which
15043 -- case only the operations of the partial view are available in the
15044 -- generic. Subsequent checks may be required when the full view is
15045 -- analyzed to verify that a derivation from a tagged type has an
15048 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15051 elsif No (Underlying_Type (Parent_Type))
15052 or else Has_Private_Component (Parent_Type)
15055 ("premature derivation of derived or private type", Indic);
15057 -- Flag the type itself as being in error, this prevents some
15058 -- nasty problems with subsequent uses of the malformed type.
15060 Set_Error_Posted (T);
15062 -- Check that within the immediate scope of an untagged partial
15063 -- view it's illegal to derive from the partial view if the
15064 -- full view is tagged. (7.3(7))
15066 -- We verify that the Parent_Type is a partial view by checking
15067 -- that it is not a Full_Type_Declaration (i.e. a private type or
15068 -- private extension declaration), to distinguish a partial view
15069 -- from a derivation from a private type which also appears as
15070 -- E_Private_Type. If the parent base type is not declared in an
15071 -- enclosing scope there is no need to check.
15073 elsif Present (Full_View (Parent_Type))
15074 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15075 and then not Is_Tagged_Type (Parent_Type)
15076 and then Is_Tagged_Type (Full_View (Parent_Type))
15077 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15080 ("premature derivation from type with tagged full view",
15085 -- Check that form of derivation is appropriate
15087 Taggd := Is_Tagged_Type (Parent_Type);
15089 -- Perhaps the parent type should be changed to the class-wide type's
15090 -- specific type in this case to prevent cascading errors ???
15092 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15093 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15097 if Present (Extension) and then not Taggd then
15099 ("type derived from untagged type cannot have extension", Indic);
15101 elsif No (Extension) and then Taggd then
15103 -- If this declaration is within a private part (or body) of a
15104 -- generic instantiation then the derivation is allowed (the parent
15105 -- type can only appear tagged in this case if it's a generic actual
15106 -- type, since it would otherwise have been rejected in the analysis
15107 -- of the generic template).
15109 if not Is_Generic_Actual_Type (Parent_Type)
15110 or else In_Visible_Part (Scope (Parent_Type))
15112 if Is_Class_Wide_Type (Parent_Type) then
15114 ("parent type must not be a class-wide type", Indic);
15116 -- Use specific type to prevent cascaded errors.
15118 Parent_Type := Etype (Parent_Type);
15122 ("type derived from tagged type must have extension", Indic);
15127 -- AI-443: Synchronized formal derived types require a private
15128 -- extension. There is no point in checking the ancestor type or
15129 -- the progenitors since the construct is wrong to begin with.
15131 if Ada_Version >= Ada_2005
15132 and then Is_Generic_Type (T)
15133 and then Present (Original_Node (N))
15136 Decl : constant Node_Id := Original_Node (N);
15139 if Nkind (Decl) = N_Formal_Type_Declaration
15140 and then Nkind (Formal_Type_Definition (Decl)) =
15141 N_Formal_Derived_Type_Definition
15142 and then Synchronized_Present (Formal_Type_Definition (Decl))
15143 and then No (Extension)
15145 -- Avoid emitting a duplicate error message
15147 and then not Error_Posted (Indic)
15150 ("synchronized derived type must have extension", N);
15155 if Null_Exclusion_Present (Def)
15156 and then not Is_Access_Type (Parent_Type)
15158 Error_Msg_N ("null exclusion can only apply to an access type", N);
15161 -- Avoid deriving parent primitives of underlying record views
15163 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15164 Derive_Subps => not Is_Underlying_Record_View (T));
15166 -- AI-419: The parent type of an explicitly limited derived type must
15167 -- be a limited type or a limited interface.
15169 if Limited_Present (Def) then
15170 Set_Is_Limited_Record (T);
15172 if Is_Interface (T) then
15173 Set_Is_Limited_Interface (T);
15176 if not Is_Limited_Type (Parent_Type)
15178 (not Is_Interface (Parent_Type)
15179 or else not Is_Limited_Interface (Parent_Type))
15181 -- AI05-0096: a derivation in the private part of an instance is
15182 -- legal if the generic formal is untagged limited, and the actual
15185 if Is_Generic_Actual_Type (Parent_Type)
15186 and then In_Private_Part (Current_Scope)
15189 (Generic_Parent_Type (Parent (Parent_Type)))
15195 ("parent type& of limited type must be limited",
15201 -- In SPARK, there are no derived type definitions other than type
15202 -- extensions of tagged record types.
15204 if No (Extension) then
15205 Check_SPARK_Restriction
15206 ("derived type is not allowed", Original_Node (N));
15208 end Derived_Type_Declaration;
15210 ------------------------
15211 -- Diagnose_Interface --
15212 ------------------------
15214 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15216 if not Is_Interface (E)
15217 and then E /= Any_Type
15219 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15221 end Diagnose_Interface;
15223 ----------------------------------
15224 -- Enumeration_Type_Declaration --
15225 ----------------------------------
15227 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15234 -- Create identifier node representing lower bound
15236 B_Node := New_Node (N_Identifier, Sloc (Def));
15237 L := First (Literals (Def));
15238 Set_Chars (B_Node, Chars (L));
15239 Set_Entity (B_Node, L);
15240 Set_Etype (B_Node, T);
15241 Set_Is_Static_Expression (B_Node, True);
15243 R_Node := New_Node (N_Range, Sloc (Def));
15244 Set_Low_Bound (R_Node, B_Node);
15246 Set_Ekind (T, E_Enumeration_Type);
15247 Set_First_Literal (T, L);
15249 Set_Is_Constrained (T);
15253 -- Loop through literals of enumeration type setting pos and rep values
15254 -- except that if the Ekind is already set, then it means the literal
15255 -- was already constructed (case of a derived type declaration and we
15256 -- should not disturb the Pos and Rep values.
15258 while Present (L) loop
15259 if Ekind (L) /= E_Enumeration_Literal then
15260 Set_Ekind (L, E_Enumeration_Literal);
15261 Set_Enumeration_Pos (L, Ev);
15262 Set_Enumeration_Rep (L, Ev);
15263 Set_Is_Known_Valid (L, True);
15267 New_Overloaded_Entity (L);
15268 Generate_Definition (L);
15269 Set_Convention (L, Convention_Intrinsic);
15271 -- Case of character literal
15273 if Nkind (L) = N_Defining_Character_Literal then
15274 Set_Is_Character_Type (T, True);
15276 -- Check violation of No_Wide_Characters
15278 if Restriction_Check_Required (No_Wide_Characters) then
15279 Get_Name_String (Chars (L));
15281 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
15282 Check_Restriction (No_Wide_Characters, L);
15291 -- Now create a node representing upper bound
15293 B_Node := New_Node (N_Identifier, Sloc (Def));
15294 Set_Chars (B_Node, Chars (Last (Literals (Def))));
15295 Set_Entity (B_Node, Last (Literals (Def)));
15296 Set_Etype (B_Node, T);
15297 Set_Is_Static_Expression (B_Node, True);
15299 Set_High_Bound (R_Node, B_Node);
15301 -- Initialize various fields of the type. Some of this information
15302 -- may be overwritten later through rep.clauses.
15304 Set_Scalar_Range (T, R_Node);
15305 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
15306 Set_Enum_Esize (T);
15307 Set_Enum_Pos_To_Rep (T, Empty);
15309 -- Set Discard_Names if configuration pragma set, or if there is
15310 -- a parameterless pragma in the current declarative region
15312 if Global_Discard_Names or else Discard_Names (Scope (T)) then
15313 Set_Discard_Names (T);
15316 -- Process end label if there is one
15318 if Present (Def) then
15319 Process_End_Label (Def, 'e', T);
15321 end Enumeration_Type_Declaration;
15323 ---------------------------------
15324 -- Expand_To_Stored_Constraint --
15325 ---------------------------------
15327 function Expand_To_Stored_Constraint
15329 Constraint : Elist_Id) return Elist_Id
15331 Explicitly_Discriminated_Type : Entity_Id;
15332 Expansion : Elist_Id;
15333 Discriminant : Entity_Id;
15335 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
15336 -- Find the nearest type that actually specifies discriminants
15338 ---------------------------------
15339 -- Type_With_Explicit_Discrims --
15340 ---------------------------------
15342 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
15343 Typ : constant E := Base_Type (Id);
15346 if Ekind (Typ) in Incomplete_Or_Private_Kind then
15347 if Present (Full_View (Typ)) then
15348 return Type_With_Explicit_Discrims (Full_View (Typ));
15352 if Has_Discriminants (Typ) then
15357 if Etype (Typ) = Typ then
15359 elsif Has_Discriminants (Typ) then
15362 return Type_With_Explicit_Discrims (Etype (Typ));
15365 end Type_With_Explicit_Discrims;
15367 -- Start of processing for Expand_To_Stored_Constraint
15371 or else Is_Empty_Elmt_List (Constraint)
15376 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
15378 if No (Explicitly_Discriminated_Type) then
15382 Expansion := New_Elmt_List;
15385 First_Stored_Discriminant (Explicitly_Discriminated_Type);
15386 while Present (Discriminant) loop
15388 Get_Discriminant_Value (
15389 Discriminant, Explicitly_Discriminated_Type, Constraint),
15391 Next_Stored_Discriminant (Discriminant);
15395 end Expand_To_Stored_Constraint;
15397 ---------------------------
15398 -- Find_Hidden_Interface --
15399 ---------------------------
15401 function Find_Hidden_Interface
15403 Dest : Elist_Id) return Entity_Id
15406 Iface_Elmt : Elmt_Id;
15409 if Present (Src) and then Present (Dest) then
15410 Iface_Elmt := First_Elmt (Src);
15411 while Present (Iface_Elmt) loop
15412 Iface := Node (Iface_Elmt);
15414 if Is_Interface (Iface)
15415 and then not Contain_Interface (Iface, Dest)
15420 Next_Elmt (Iface_Elmt);
15425 end Find_Hidden_Interface;
15427 --------------------
15428 -- Find_Type_Name --
15429 --------------------
15431 function Find_Type_Name (N : Node_Id) return Entity_Id is
15432 Id : constant Entity_Id := Defining_Identifier (N);
15434 New_Id : Entity_Id;
15435 Prev_Par : Node_Id;
15437 procedure Check_Duplicate_Aspects;
15438 -- Check that aspects specified in a completion have not been specified
15439 -- already in the partial view. Type_Invariant and others can be
15440 -- specified on either view but never on both.
15442 procedure Tag_Mismatch;
15443 -- Diagnose a tagged partial view whose full view is untagged.
15444 -- We post the message on the full view, with a reference to
15445 -- the previous partial view. The partial view can be private
15446 -- or incomplete, and these are handled in a different manner,
15447 -- so we determine the position of the error message from the
15448 -- respective slocs of both.
15450 -----------------------------
15451 -- Check_Duplicate_Aspects --
15452 -----------------------------
15453 procedure Check_Duplicate_Aspects is
15454 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
15455 Full_Aspects : constant List_Id := Aspect_Specifications (N);
15456 F_Spec, P_Spec : Node_Id;
15459 if Present (Prev_Aspects) and then Present (Full_Aspects) then
15460 F_Spec := First (Full_Aspects);
15461 while Present (F_Spec) loop
15462 P_Spec := First (Prev_Aspects);
15463 while Present (P_Spec) loop
15465 Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
15468 ("aspect already specified in private declaration",
15480 end Check_Duplicate_Aspects;
15486 procedure Tag_Mismatch is
15488 if Sloc (Prev) < Sloc (Id) then
15489 if Ada_Version >= Ada_2012
15490 and then Nkind (N) = N_Private_Type_Declaration
15493 ("declaration of private } must be a tagged type ", Id, Prev);
15496 ("full declaration of } must be a tagged type ", Id, Prev);
15500 if Ada_Version >= Ada_2012
15501 and then Nkind (N) = N_Private_Type_Declaration
15504 ("declaration of private } must be a tagged type ", Prev, Id);
15507 ("full declaration of } must be a tagged type ", Prev, Id);
15512 -- Start of processing for Find_Type_Name
15515 -- Find incomplete declaration, if one was given
15517 Prev := Current_Entity_In_Scope (Id);
15519 -- New type declaration
15525 -- Previous declaration exists
15528 Prev_Par := Parent (Prev);
15530 -- Error if not incomplete/private case except if previous
15531 -- declaration is implicit, etc. Enter_Name will emit error if
15534 if not Is_Incomplete_Or_Private_Type (Prev) then
15538 -- Check invalid completion of private or incomplete type
15540 elsif not Nkind_In (N, N_Full_Type_Declaration,
15541 N_Task_Type_Declaration,
15542 N_Protected_Type_Declaration)
15544 (Ada_Version < Ada_2012
15545 or else not Is_Incomplete_Type (Prev)
15546 or else not Nkind_In (N, N_Private_Type_Declaration,
15547 N_Private_Extension_Declaration))
15549 -- Completion must be a full type declarations (RM 7.3(4))
15551 Error_Msg_Sloc := Sloc (Prev);
15552 Error_Msg_NE ("invalid completion of }", Id, Prev);
15554 -- Set scope of Id to avoid cascaded errors. Entity is never
15555 -- examined again, except when saving globals in generics.
15557 Set_Scope (Id, Current_Scope);
15560 -- If this is a repeated incomplete declaration, no further
15561 -- checks are possible.
15563 if Nkind (N) = N_Incomplete_Type_Declaration then
15567 -- Case of full declaration of incomplete type
15569 elsif Ekind (Prev) = E_Incomplete_Type
15570 and then (Ada_Version < Ada_2012
15571 or else No (Full_View (Prev))
15572 or else not Is_Private_Type (Full_View (Prev)))
15574 -- Indicate that the incomplete declaration has a matching full
15575 -- declaration. The defining occurrence of the incomplete
15576 -- declaration remains the visible one, and the procedure
15577 -- Get_Full_View dereferences it whenever the type is used.
15579 if Present (Full_View (Prev)) then
15580 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15583 Set_Full_View (Prev, Id);
15584 Append_Entity (Id, Current_Scope);
15585 Set_Is_Public (Id, Is_Public (Prev));
15586 Set_Is_Internal (Id);
15589 -- If the incomplete view is tagged, a class_wide type has been
15590 -- created already. Use it for the private type as well, in order
15591 -- to prevent multiple incompatible class-wide types that may be
15592 -- created for self-referential anonymous access components.
15594 if Is_Tagged_Type (Prev)
15595 and then Present (Class_Wide_Type (Prev))
15597 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
15598 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
15600 -- If the incomplete type is completed by a private declaration
15601 -- the class-wide type remains associated with the incomplete
15602 -- type, to prevent order-of-elaboration issues in gigi, else
15603 -- we associate the class-wide type with the known full view.
15605 if Nkind (N) /= N_Private_Type_Declaration then
15606 Set_Etype (Class_Wide_Type (Id), Id);
15610 -- Case of full declaration of private type
15613 -- If the private type was a completion of an incomplete type then
15614 -- update Prev to reference the private type
15616 if Ada_Version >= Ada_2012
15617 and then Ekind (Prev) = E_Incomplete_Type
15618 and then Present (Full_View (Prev))
15619 and then Is_Private_Type (Full_View (Prev))
15621 Prev := Full_View (Prev);
15622 Prev_Par := Parent (Prev);
15625 if Nkind (N) = N_Full_Type_Declaration
15627 (Type_Definition (N), N_Record_Definition,
15628 N_Derived_Type_Definition)
15629 and then Interface_Present (Type_Definition (N))
15632 ("completion of private type cannot be an interface", N);
15635 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
15636 if Etype (Prev) /= Prev then
15638 -- Prev is a private subtype or a derived type, and needs
15641 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15644 elsif Ekind (Prev) = E_Private_Type
15645 and then Nkind_In (N, N_Task_Type_Declaration,
15646 N_Protected_Type_Declaration)
15649 ("completion of nonlimited type cannot be limited", N);
15651 elsif Ekind (Prev) = E_Record_Type_With_Private
15652 and then Nkind_In (N, N_Task_Type_Declaration,
15653 N_Protected_Type_Declaration)
15655 if not Is_Limited_Record (Prev) then
15657 ("completion of nonlimited type cannot be limited", N);
15659 elsif No (Interface_List (N)) then
15661 ("completion of tagged private type must be tagged",
15666 -- Ada 2005 (AI-251): Private extension declaration of a task
15667 -- type or a protected type. This case arises when covering
15668 -- interface types.
15670 elsif Nkind_In (N, N_Task_Type_Declaration,
15671 N_Protected_Type_Declaration)
15675 elsif Nkind (N) /= N_Full_Type_Declaration
15676 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
15679 ("full view of private extension must be an extension", N);
15681 elsif not (Abstract_Present (Parent (Prev)))
15682 and then Abstract_Present (Type_Definition (N))
15685 ("full view of non-abstract extension cannot be abstract", N);
15688 if not In_Private_Part (Current_Scope) then
15690 ("declaration of full view must appear in private part", N);
15693 if Ada_Version >= Ada_2012 then
15694 Check_Duplicate_Aspects;
15697 Copy_And_Swap (Prev, Id);
15698 Set_Has_Private_Declaration (Prev);
15699 Set_Has_Private_Declaration (Id);
15701 -- Preserve aspect and iterator flags that may have been set on
15702 -- the partial view.
15704 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
15705 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
15707 -- If no error, propagate freeze_node from private to full view.
15708 -- It may have been generated for an early operational item.
15710 if Present (Freeze_Node (Id))
15711 and then Serious_Errors_Detected = 0
15712 and then No (Full_View (Id))
15714 Set_Freeze_Node (Prev, Freeze_Node (Id));
15715 Set_Freeze_Node (Id, Empty);
15716 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
15719 Set_Full_View (Id, Prev);
15723 -- Verify that full declaration conforms to partial one
15725 if Is_Incomplete_Or_Private_Type (Prev)
15726 and then Present (Discriminant_Specifications (Prev_Par))
15728 if Present (Discriminant_Specifications (N)) then
15729 if Ekind (Prev) = E_Incomplete_Type then
15730 Check_Discriminant_Conformance (N, Prev, Prev);
15732 Check_Discriminant_Conformance (N, Prev, Id);
15737 ("missing discriminants in full type declaration", N);
15739 -- To avoid cascaded errors on subsequent use, share the
15740 -- discriminants of the partial view.
15742 Set_Discriminant_Specifications (N,
15743 Discriminant_Specifications (Prev_Par));
15747 -- A prior untagged partial view can have an associated class-wide
15748 -- type due to use of the class attribute, and in this case the full
15749 -- type must also be tagged. This Ada 95 usage is deprecated in favor
15750 -- of incomplete tagged declarations, but we check for it.
15753 and then (Is_Tagged_Type (Prev)
15754 or else Present (Class_Wide_Type (Prev)))
15756 -- Ada 2012 (AI05-0162): A private type may be the completion of
15757 -- an incomplete type.
15759 if Ada_Version >= Ada_2012
15760 and then Is_Incomplete_Type (Prev)
15761 and then Nkind_In (N, N_Private_Type_Declaration,
15762 N_Private_Extension_Declaration)
15764 -- No need to check private extensions since they are tagged
15766 if Nkind (N) = N_Private_Type_Declaration
15767 and then not Tagged_Present (N)
15772 -- The full declaration is either a tagged type (including
15773 -- a synchronized type that implements interfaces) or a
15774 -- type extension, otherwise this is an error.
15776 elsif Nkind_In (N, N_Task_Type_Declaration,
15777 N_Protected_Type_Declaration)
15779 if No (Interface_List (N))
15780 and then not Error_Posted (N)
15785 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15787 -- Indicate that the previous declaration (tagged incomplete
15788 -- or private declaration) requires the same on the full one.
15790 if not Tagged_Present (Type_Definition (N)) then
15792 Set_Is_Tagged_Type (Id);
15795 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15796 if No (Record_Extension_Part (Type_Definition (N))) then
15798 ("full declaration of } must be a record extension",
15801 -- Set some attributes to produce a usable full view
15803 Set_Is_Tagged_Type (Id);
15812 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
15813 and then Present (Premature_Use (Parent (Prev)))
15815 Error_Msg_Sloc := Sloc (N);
15817 ("\full declaration #", Premature_Use (Parent (Prev)));
15822 end Find_Type_Name;
15824 -------------------------
15825 -- Find_Type_Of_Object --
15826 -------------------------
15828 function Find_Type_Of_Object
15829 (Obj_Def : Node_Id;
15830 Related_Nod : Node_Id) return Entity_Id
15832 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15833 P : Node_Id := Parent (Obj_Def);
15838 -- If the parent is a component_definition node we climb to the
15839 -- component_declaration node
15841 if Nkind (P) = N_Component_Definition then
15845 -- Case of an anonymous array subtype
15847 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15848 N_Unconstrained_Array_Definition)
15851 Array_Type_Declaration (T, Obj_Def);
15853 -- Create an explicit subtype whenever possible
15855 elsif Nkind (P) /= N_Component_Declaration
15856 and then Def_Kind = N_Subtype_Indication
15858 -- Base name of subtype on object name, which will be unique in
15859 -- the current scope.
15861 -- If this is a duplicate declaration, return base type, to avoid
15862 -- generating duplicate anonymous types.
15864 if Error_Posted (P) then
15865 Analyze (Subtype_Mark (Obj_Def));
15866 return Entity (Subtype_Mark (Obj_Def));
15871 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15873 T := Make_Defining_Identifier (Sloc (P), Nam);
15875 Insert_Action (Obj_Def,
15876 Make_Subtype_Declaration (Sloc (P),
15877 Defining_Identifier => T,
15878 Subtype_Indication => Relocate_Node (Obj_Def)));
15880 -- This subtype may need freezing, and this will not be done
15881 -- automatically if the object declaration is not in declarative
15882 -- part. Since this is an object declaration, the type cannot always
15883 -- be frozen here. Deferred constants do not freeze their type
15884 -- (which often enough will be private).
15886 if Nkind (P) = N_Object_Declaration
15887 and then Constant_Present (P)
15888 and then No (Expression (P))
15892 -- Here we freeze the base type of object type to catch premature use
15893 -- of discriminated private type without a full view.
15896 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
15899 -- Ada 2005 AI-406: the object definition in an object declaration
15900 -- can be an access definition.
15902 elsif Def_Kind = N_Access_Definition then
15903 T := Access_Definition (Related_Nod, Obj_Def);
15905 Set_Is_Local_Anonymous_Access
15907 V => (Ada_Version < Ada_2012)
15908 or else (Nkind (P) /= N_Object_Declaration)
15909 or else Is_Library_Level_Entity (Defining_Identifier (P)));
15911 -- Otherwise, the object definition is just a subtype_mark
15914 T := Process_Subtype (Obj_Def, Related_Nod);
15916 -- If expansion is disabled an object definition that is an aggregate
15917 -- will not get expanded and may lead to scoping problems in the back
15918 -- end, if the object is referenced in an inner scope. In that case
15919 -- create an itype reference for the object definition now. This
15920 -- may be redundant in some cases, but harmless.
15923 and then Nkind (Related_Nod) = N_Object_Declaration
15926 Build_Itype_Reference (T, Related_Nod);
15931 end Find_Type_Of_Object;
15933 --------------------------------
15934 -- Find_Type_Of_Subtype_Indic --
15935 --------------------------------
15937 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15941 -- Case of subtype mark with a constraint
15943 if Nkind (S) = N_Subtype_Indication then
15944 Find_Type (Subtype_Mark (S));
15945 Typ := Entity (Subtype_Mark (S));
15948 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15951 ("incorrect constraint for this kind of type", Constraint (S));
15952 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15955 -- Otherwise we have a subtype mark without a constraint
15957 elsif Error_Posted (S) then
15958 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15966 -- Check No_Wide_Characters restriction
15968 Check_Wide_Character_Restriction (Typ, S);
15971 end Find_Type_Of_Subtype_Indic;
15973 -------------------------------------
15974 -- Floating_Point_Type_Declaration --
15975 -------------------------------------
15977 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15978 Digs : constant Node_Id := Digits_Expression (Def);
15979 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15981 Base_Typ : Entity_Id;
15982 Implicit_Base : Entity_Id;
15985 function Can_Derive_From (E : Entity_Id) return Boolean;
15986 -- Find if given digits value, and possibly a specified range, allows
15987 -- derivation from specified type
15989 function Find_Base_Type return Entity_Id;
15990 -- Find a predefined base type that Def can derive from, or generate
15991 -- an error and substitute Long_Long_Float if none exists.
15993 ---------------------
15994 -- Can_Derive_From --
15995 ---------------------
15997 function Can_Derive_From (E : Entity_Id) return Boolean is
15998 Spec : constant Entity_Id := Real_Range_Specification (Def);
16001 -- Check specified "digits" constraint
16003 if Digs_Val > Digits_Value (E) then
16007 -- Avoid types not matching pragma Float_Representation, if present
16009 if (Opt.Float_Format = 'I' and then Float_Rep (E) /= IEEE_Binary)
16011 (Opt.Float_Format = 'V' and then Float_Rep (E) /= VAX_Native)
16016 -- Check for matching range, if specified
16018 if Present (Spec) then
16019 if Expr_Value_R (Type_Low_Bound (E)) >
16020 Expr_Value_R (Low_Bound (Spec))
16025 if Expr_Value_R (Type_High_Bound (E)) <
16026 Expr_Value_R (High_Bound (Spec))
16033 end Can_Derive_From;
16035 --------------------
16036 -- Find_Base_Type --
16037 --------------------
16039 function Find_Base_Type return Entity_Id is
16040 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16043 -- Iterate over the predefined types in order, returning the first
16044 -- one that Def can derive from.
16046 while Present (Choice) loop
16047 if Can_Derive_From (Node (Choice)) then
16048 return Node (Choice);
16051 Next_Elmt (Choice);
16054 -- If we can't derive from any existing type, use Long_Long_Float
16055 -- and give appropriate message explaining the problem.
16057 if Digs_Val > Max_Digs_Val then
16058 -- It might be the case that there is a type with the requested
16059 -- range, just not the combination of digits and range.
16062 ("no predefined type has requested range and precision",
16063 Real_Range_Specification (Def));
16067 ("range too large for any predefined type",
16068 Real_Range_Specification (Def));
16071 return Standard_Long_Long_Float;
16072 end Find_Base_Type;
16074 -- Start of processing for Floating_Point_Type_Declaration
16077 Check_Restriction (No_Floating_Point, Def);
16079 -- Create an implicit base type
16082 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16084 -- Analyze and verify digits value
16086 Analyze_And_Resolve (Digs, Any_Integer);
16087 Check_Digits_Expression (Digs);
16088 Digs_Val := Expr_Value (Digs);
16090 -- Process possible range spec and find correct type to derive from
16092 Process_Real_Range_Specification (Def);
16094 -- Check that requested number of digits is not too high.
16096 if Digs_Val > Max_Digs_Val then
16097 -- The check for Max_Base_Digits may be somewhat expensive, as it
16098 -- requires reading System, so only do it when necessary.
16101 Max_Base_Digits : constant Uint :=
16104 (Parent (RTE (RE_Max_Base_Digits))));
16107 if Digs_Val > Max_Base_Digits then
16108 Error_Msg_Uint_1 := Max_Base_Digits;
16109 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16111 elsif No (Real_Range_Specification (Def)) then
16112 Error_Msg_Uint_1 := Max_Digs_Val;
16113 Error_Msg_N ("types with more than ^ digits need range spec "
16114 & "(RM 3.5.7(6))", Digs);
16119 -- Find a suitable type to derive from or complain and use a substitute
16121 Base_Typ := Find_Base_Type;
16123 -- If there are bounds given in the declaration use them as the bounds
16124 -- of the type, otherwise use the bounds of the predefined base type
16125 -- that was chosen based on the Digits value.
16127 if Present (Real_Range_Specification (Def)) then
16128 Set_Scalar_Range (T, Real_Range_Specification (Def));
16129 Set_Is_Constrained (T);
16131 -- The bounds of this range must be converted to machine numbers
16132 -- in accordance with RM 4.9(38).
16134 Bound := Type_Low_Bound (T);
16136 if Nkind (Bound) = N_Real_Literal then
16138 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16139 Set_Is_Machine_Number (Bound);
16142 Bound := Type_High_Bound (T);
16144 if Nkind (Bound) = N_Real_Literal then
16146 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16147 Set_Is_Machine_Number (Bound);
16151 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16154 -- Complete definition of implicit base and declared first subtype
16156 Set_Etype (Implicit_Base, Base_Typ);
16158 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16159 Set_Size_Info (Implicit_Base, (Base_Typ));
16160 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16161 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16162 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16163 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16165 Set_Ekind (T, E_Floating_Point_Subtype);
16166 Set_Etype (T, Implicit_Base);
16168 Set_Size_Info (T, (Implicit_Base));
16169 Set_RM_Size (T, RM_Size (Implicit_Base));
16170 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16171 Set_Digits_Value (T, Digs_Val);
16172 end Floating_Point_Type_Declaration;
16174 ----------------------------
16175 -- Get_Discriminant_Value --
16176 ----------------------------
16178 -- This is the situation:
16180 -- There is a non-derived type
16182 -- type T0 (Dx, Dy, Dz...)
16184 -- There are zero or more levels of derivation, with each derivation
16185 -- either purely inheriting the discriminants, or defining its own.
16187 -- type Ti is new Ti-1
16189 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16191 -- subtype Ti is ...
16193 -- The subtype issue is avoided by the use of Original_Record_Component,
16194 -- and the fact that derived subtypes also derive the constraints.
16196 -- This chain leads back from
16198 -- Typ_For_Constraint
16200 -- Typ_For_Constraint has discriminants, and the value for each
16201 -- discriminant is given by its corresponding Elmt of Constraints.
16203 -- Discriminant is some discriminant in this hierarchy
16205 -- We need to return its value
16207 -- We do this by recursively searching each level, and looking for
16208 -- Discriminant. Once we get to the bottom, we start backing up
16209 -- returning the value for it which may in turn be a discriminant
16210 -- further up, so on the backup we continue the substitution.
16212 function Get_Discriminant_Value
16213 (Discriminant : Entity_Id;
16214 Typ_For_Constraint : Entity_Id;
16215 Constraint : Elist_Id) return Node_Id
16217 function Root_Corresponding_Discriminant
16218 (Discr : Entity_Id) return Entity_Id;
16219 -- Given a discriminant, traverse the chain of inherited discriminants
16220 -- and return the topmost discriminant.
16222 function Search_Derivation_Levels
16224 Discrim_Values : Elist_Id;
16225 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16226 -- This is the routine that performs the recursive search of levels
16227 -- as described above.
16229 -------------------------------------
16230 -- Root_Corresponding_Discriminant --
16231 -------------------------------------
16233 function Root_Corresponding_Discriminant
16234 (Discr : Entity_Id) return Entity_Id
16240 while Present (Corresponding_Discriminant (D)) loop
16241 D := Corresponding_Discriminant (D);
16245 end Root_Corresponding_Discriminant;
16247 ------------------------------
16248 -- Search_Derivation_Levels --
16249 ------------------------------
16251 function Search_Derivation_Levels
16253 Discrim_Values : Elist_Id;
16254 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
16258 Result : Node_Or_Entity_Id;
16259 Result_Entity : Node_Id;
16262 -- If inappropriate type, return Error, this happens only in
16263 -- cascaded error situations, and we want to avoid a blow up.
16265 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
16269 -- Look deeper if possible. Use Stored_Constraints only for
16270 -- untagged types. For tagged types use the given constraint.
16271 -- This asymmetry needs explanation???
16273 if not Stored_Discrim_Values
16274 and then Present (Stored_Constraint (Ti))
16275 and then not Is_Tagged_Type (Ti)
16278 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
16281 Td : constant Entity_Id := Etype (Ti);
16285 Result := Discriminant;
16288 if Present (Stored_Constraint (Ti)) then
16290 Search_Derivation_Levels
16291 (Td, Stored_Constraint (Ti), True);
16294 Search_Derivation_Levels
16295 (Td, Discrim_Values, Stored_Discrim_Values);
16301 -- Extra underlying places to search, if not found above. For
16302 -- concurrent types, the relevant discriminant appears in the
16303 -- corresponding record. For a type derived from a private type
16304 -- without discriminant, the full view inherits the discriminants
16305 -- of the full view of the parent.
16307 if Result = Discriminant then
16308 if Is_Concurrent_Type (Ti)
16309 and then Present (Corresponding_Record_Type (Ti))
16312 Search_Derivation_Levels (
16313 Corresponding_Record_Type (Ti),
16315 Stored_Discrim_Values);
16317 elsif Is_Private_Type (Ti)
16318 and then not Has_Discriminants (Ti)
16319 and then Present (Full_View (Ti))
16320 and then Etype (Full_View (Ti)) /= Ti
16323 Search_Derivation_Levels (
16326 Stored_Discrim_Values);
16330 -- If Result is not a (reference to a) discriminant, return it,
16331 -- otherwise set Result_Entity to the discriminant.
16333 if Nkind (Result) = N_Defining_Identifier then
16334 pragma Assert (Result = Discriminant);
16335 Result_Entity := Result;
16338 if not Denotes_Discriminant (Result) then
16342 Result_Entity := Entity (Result);
16345 -- See if this level of derivation actually has discriminants
16346 -- because tagged derivations can add them, hence the lower
16347 -- levels need not have any.
16349 if not Has_Discriminants (Ti) then
16353 -- Scan Ti's discriminants for Result_Entity,
16354 -- and return its corresponding value, if any.
16356 Result_Entity := Original_Record_Component (Result_Entity);
16358 Assoc := First_Elmt (Discrim_Values);
16360 if Stored_Discrim_Values then
16361 Disc := First_Stored_Discriminant (Ti);
16363 Disc := First_Discriminant (Ti);
16366 while Present (Disc) loop
16367 pragma Assert (Present (Assoc));
16369 if Original_Record_Component (Disc) = Result_Entity then
16370 return Node (Assoc);
16375 if Stored_Discrim_Values then
16376 Next_Stored_Discriminant (Disc);
16378 Next_Discriminant (Disc);
16382 -- Could not find it
16385 end Search_Derivation_Levels;
16389 Result : Node_Or_Entity_Id;
16391 -- Start of processing for Get_Discriminant_Value
16394 -- ??? This routine is a gigantic mess and will be deleted. For the
16395 -- time being just test for the trivial case before calling recurse.
16397 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
16403 D := First_Discriminant (Typ_For_Constraint);
16404 E := First_Elmt (Constraint);
16405 while Present (D) loop
16406 if Chars (D) = Chars (Discriminant) then
16410 Next_Discriminant (D);
16416 Result := Search_Derivation_Levels
16417 (Typ_For_Constraint, Constraint, False);
16419 -- ??? hack to disappear when this routine is gone
16421 if Nkind (Result) = N_Defining_Identifier then
16427 D := First_Discriminant (Typ_For_Constraint);
16428 E := First_Elmt (Constraint);
16429 while Present (D) loop
16430 if Root_Corresponding_Discriminant (D) = Discriminant then
16434 Next_Discriminant (D);
16440 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
16442 end Get_Discriminant_Value;
16444 --------------------------
16445 -- Has_Range_Constraint --
16446 --------------------------
16448 function Has_Range_Constraint (N : Node_Id) return Boolean is
16449 C : constant Node_Id := Constraint (N);
16452 if Nkind (C) = N_Range_Constraint then
16455 elsif Nkind (C) = N_Digits_Constraint then
16457 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
16459 Present (Range_Constraint (C));
16461 elsif Nkind (C) = N_Delta_Constraint then
16462 return Present (Range_Constraint (C));
16467 end Has_Range_Constraint;
16469 ------------------------
16470 -- Inherit_Components --
16471 ------------------------
16473 function Inherit_Components
16475 Parent_Base : Entity_Id;
16476 Derived_Base : Entity_Id;
16477 Is_Tagged : Boolean;
16478 Inherit_Discr : Boolean;
16479 Discs : Elist_Id) return Elist_Id
16481 Assoc_List : constant Elist_Id := New_Elmt_List;
16483 procedure Inherit_Component
16484 (Old_C : Entity_Id;
16485 Plain_Discrim : Boolean := False;
16486 Stored_Discrim : Boolean := False);
16487 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
16488 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
16489 -- True, Old_C is a stored discriminant. If they are both false then
16490 -- Old_C is a regular component.
16492 -----------------------
16493 -- Inherit_Component --
16494 -----------------------
16496 procedure Inherit_Component
16497 (Old_C : Entity_Id;
16498 Plain_Discrim : Boolean := False;
16499 Stored_Discrim : Boolean := False)
16501 procedure Set_Anonymous_Type (Id : Entity_Id);
16502 -- Id denotes the entity of an access discriminant or anonymous
16503 -- access component. Set the type of Id to either the same type of
16504 -- Old_C or create a new one depending on whether the parent and
16505 -- the child types are in the same scope.
16507 ------------------------
16508 -- Set_Anonymous_Type --
16509 ------------------------
16511 procedure Set_Anonymous_Type (Id : Entity_Id) is
16512 Old_Typ : constant Entity_Id := Etype (Old_C);
16515 if Scope (Parent_Base) = Scope (Derived_Base) then
16516 Set_Etype (Id, Old_Typ);
16518 -- The parent and the derived type are in two different scopes.
16519 -- Reuse the type of the original discriminant / component by
16520 -- copying it in order to preserve all attributes.
16524 Typ : constant Entity_Id := New_Copy (Old_Typ);
16527 Set_Etype (Id, Typ);
16529 -- Since we do not generate component declarations for
16530 -- inherited components, associate the itype with the
16533 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
16534 Set_Scope (Typ, Derived_Base);
16537 end Set_Anonymous_Type;
16539 -- Local variables and constants
16541 New_C : constant Entity_Id := New_Copy (Old_C);
16543 Corr_Discrim : Entity_Id;
16544 Discrim : Entity_Id;
16546 -- Start of processing for Inherit_Component
16549 pragma Assert (not Is_Tagged or else not Stored_Discrim);
16551 Set_Parent (New_C, Parent (Old_C));
16553 -- Regular discriminants and components must be inserted in the scope
16554 -- of the Derived_Base. Do it here.
16556 if not Stored_Discrim then
16557 Enter_Name (New_C);
16560 -- For tagged types the Original_Record_Component must point to
16561 -- whatever this field was pointing to in the parent type. This has
16562 -- already been achieved by the call to New_Copy above.
16564 if not Is_Tagged then
16565 Set_Original_Record_Component (New_C, New_C);
16568 -- Set the proper type of an access discriminant
16570 if Ekind (New_C) = E_Discriminant
16571 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
16573 Set_Anonymous_Type (New_C);
16576 -- If we have inherited a component then see if its Etype contains
16577 -- references to Parent_Base discriminants. In this case, replace
16578 -- these references with the constraints given in Discs. We do not
16579 -- do this for the partial view of private types because this is
16580 -- not needed (only the components of the full view will be used
16581 -- for code generation) and cause problem. We also avoid this
16582 -- transformation in some error situations.
16584 if Ekind (New_C) = E_Component then
16586 -- Set the proper type of an anonymous access component
16588 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
16589 Set_Anonymous_Type (New_C);
16591 elsif (Is_Private_Type (Derived_Base)
16592 and then not Is_Generic_Type (Derived_Base))
16593 or else (Is_Empty_Elmt_List (Discs)
16594 and then not Expander_Active)
16596 Set_Etype (New_C, Etype (Old_C));
16599 -- The current component introduces a circularity of the
16602 -- limited with Pack_2;
16603 -- package Pack_1 is
16604 -- type T_1 is tagged record
16605 -- Comp : access Pack_2.T_2;
16611 -- package Pack_2 is
16612 -- type T_2 is new Pack_1.T_1 with ...;
16617 Constrain_Component_Type
16618 (Old_C, Derived_Base, N, Parent_Base, Discs));
16622 -- In derived tagged types it is illegal to reference a non
16623 -- discriminant component in the parent type. To catch this, mark
16624 -- these components with an Ekind of E_Void. This will be reset in
16625 -- Record_Type_Definition after processing the record extension of
16626 -- the derived type.
16628 -- If the declaration is a private extension, there is no further
16629 -- record extension to process, and the components retain their
16630 -- current kind, because they are visible at this point.
16632 if Is_Tagged and then Ekind (New_C) = E_Component
16633 and then Nkind (N) /= N_Private_Extension_Declaration
16635 Set_Ekind (New_C, E_Void);
16638 if Plain_Discrim then
16639 Set_Corresponding_Discriminant (New_C, Old_C);
16640 Build_Discriminal (New_C);
16642 -- If we are explicitly inheriting a stored discriminant it will be
16643 -- completely hidden.
16645 elsif Stored_Discrim then
16646 Set_Corresponding_Discriminant (New_C, Empty);
16647 Set_Discriminal (New_C, Empty);
16648 Set_Is_Completely_Hidden (New_C);
16650 -- Set the Original_Record_Component of each discriminant in the
16651 -- derived base to point to the corresponding stored that we just
16654 Discrim := First_Discriminant (Derived_Base);
16655 while Present (Discrim) loop
16656 Corr_Discrim := Corresponding_Discriminant (Discrim);
16658 -- Corr_Discrim could be missing in an error situation
16660 if Present (Corr_Discrim)
16661 and then Original_Record_Component (Corr_Discrim) = Old_C
16663 Set_Original_Record_Component (Discrim, New_C);
16666 Next_Discriminant (Discrim);
16669 Append_Entity (New_C, Derived_Base);
16672 if not Is_Tagged then
16673 Append_Elmt (Old_C, Assoc_List);
16674 Append_Elmt (New_C, Assoc_List);
16676 end Inherit_Component;
16678 -- Variables local to Inherit_Component
16680 Loc : constant Source_Ptr := Sloc (N);
16682 Parent_Discrim : Entity_Id;
16683 Stored_Discrim : Entity_Id;
16685 Component : Entity_Id;
16687 -- Start of processing for Inherit_Components
16690 if not Is_Tagged then
16691 Append_Elmt (Parent_Base, Assoc_List);
16692 Append_Elmt (Derived_Base, Assoc_List);
16695 -- Inherit parent discriminants if needed
16697 if Inherit_Discr then
16698 Parent_Discrim := First_Discriminant (Parent_Base);
16699 while Present (Parent_Discrim) loop
16700 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
16701 Next_Discriminant (Parent_Discrim);
16705 -- Create explicit stored discrims for untagged types when necessary
16707 if not Has_Unknown_Discriminants (Derived_Base)
16708 and then Has_Discriminants (Parent_Base)
16709 and then not Is_Tagged
16712 or else First_Discriminant (Parent_Base) /=
16713 First_Stored_Discriminant (Parent_Base))
16715 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
16716 while Present (Stored_Discrim) loop
16717 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
16718 Next_Stored_Discriminant (Stored_Discrim);
16722 -- See if we can apply the second transformation for derived types, as
16723 -- explained in point 6. in the comments above Build_Derived_Record_Type
16724 -- This is achieved by appending Derived_Base discriminants into Discs,
16725 -- which has the side effect of returning a non empty Discs list to the
16726 -- caller of Inherit_Components, which is what we want. This must be
16727 -- done for private derived types if there are explicit stored
16728 -- discriminants, to ensure that we can retrieve the values of the
16729 -- constraints provided in the ancestors.
16732 and then Is_Empty_Elmt_List (Discs)
16733 and then Present (First_Discriminant (Derived_Base))
16735 (not Is_Private_Type (Derived_Base)
16736 or else Is_Completely_Hidden
16737 (First_Stored_Discriminant (Derived_Base))
16738 or else Is_Generic_Type (Derived_Base))
16740 D := First_Discriminant (Derived_Base);
16741 while Present (D) loop
16742 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
16743 Next_Discriminant (D);
16747 -- Finally, inherit non-discriminant components unless they are not
16748 -- visible because defined or inherited from the full view of the
16749 -- parent. Don't inherit the _parent field of the parent type.
16751 Component := First_Entity (Parent_Base);
16752 while Present (Component) loop
16754 -- Ada 2005 (AI-251): Do not inherit components associated with
16755 -- secondary tags of the parent.
16757 if Ekind (Component) = E_Component
16758 and then Present (Related_Type (Component))
16762 elsif Ekind (Component) /= E_Component
16763 or else Chars (Component) = Name_uParent
16767 -- If the derived type is within the parent type's declarative
16768 -- region, then the components can still be inherited even though
16769 -- they aren't visible at this point. This can occur for cases
16770 -- such as within public child units where the components must
16771 -- become visible upon entering the child unit's private part.
16773 elsif not Is_Visible_Component (Component)
16774 and then not In_Open_Scopes (Scope (Parent_Base))
16778 elsif Ekind_In (Derived_Base, E_Private_Type,
16779 E_Limited_Private_Type)
16784 Inherit_Component (Component);
16787 Next_Entity (Component);
16790 -- For tagged derived types, inherited discriminants cannot be used in
16791 -- component declarations of the record extension part. To achieve this
16792 -- we mark the inherited discriminants as not visible.
16794 if Is_Tagged and then Inherit_Discr then
16795 D := First_Discriminant (Derived_Base);
16796 while Present (D) loop
16797 Set_Is_Immediately_Visible (D, False);
16798 Next_Discriminant (D);
16803 end Inherit_Components;
16805 -----------------------
16806 -- Is_Null_Extension --
16807 -----------------------
16809 function Is_Null_Extension (T : Entity_Id) return Boolean is
16810 Type_Decl : constant Node_Id := Parent (Base_Type (T));
16811 Comp_List : Node_Id;
16815 if Nkind (Type_Decl) /= N_Full_Type_Declaration
16816 or else not Is_Tagged_Type (T)
16817 or else Nkind (Type_Definition (Type_Decl)) /=
16818 N_Derived_Type_Definition
16819 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
16825 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
16827 if Present (Discriminant_Specifications (Type_Decl)) then
16830 elsif Present (Comp_List)
16831 and then Is_Non_Empty_List (Component_Items (Comp_List))
16833 Comp := First (Component_Items (Comp_List));
16835 -- Only user-defined components are relevant. The component list
16836 -- may also contain a parent component and internal components
16837 -- corresponding to secondary tags, but these do not determine
16838 -- whether this is a null extension.
16840 while Present (Comp) loop
16841 if Comes_From_Source (Comp) then
16852 end Is_Null_Extension;
16854 ------------------------------
16855 -- Is_Valid_Constraint_Kind --
16856 ------------------------------
16858 function Is_Valid_Constraint_Kind
16859 (T_Kind : Type_Kind;
16860 Constraint_Kind : Node_Kind) return Boolean
16864 when Enumeration_Kind |
16866 return Constraint_Kind = N_Range_Constraint;
16868 when Decimal_Fixed_Point_Kind =>
16869 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16870 N_Range_Constraint);
16872 when Ordinary_Fixed_Point_Kind =>
16873 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16874 N_Range_Constraint);
16877 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16878 N_Range_Constraint);
16885 E_Incomplete_Type |
16888 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16891 return True; -- Error will be detected later
16893 end Is_Valid_Constraint_Kind;
16895 --------------------------
16896 -- Is_Visible_Component --
16897 --------------------------
16899 function Is_Visible_Component
16901 N : Node_Id := Empty) return Boolean
16903 Original_Comp : Entity_Id := Empty;
16904 Original_Scope : Entity_Id;
16905 Type_Scope : Entity_Id;
16907 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16908 -- Check whether parent type of inherited component is declared locally,
16909 -- possibly within a nested package or instance. The current scope is
16910 -- the derived record itself.
16912 -------------------
16913 -- Is_Local_Type --
16914 -------------------
16916 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16920 Scop := Scope (Typ);
16921 while Present (Scop)
16922 and then Scop /= Standard_Standard
16924 if Scop = Scope (Current_Scope) then
16928 Scop := Scope (Scop);
16934 -- Start of processing for Is_Visible_Component
16937 if Ekind_In (C, E_Component, E_Discriminant) then
16938 Original_Comp := Original_Record_Component (C);
16941 if No (Original_Comp) then
16943 -- Premature usage, or previous error
16948 Original_Scope := Scope (Original_Comp);
16949 Type_Scope := Scope (Base_Type (Scope (C)));
16952 -- For an untagged type derived from a private type, the only visible
16953 -- components are new discriminants. In an instance all components are
16954 -- visible (see Analyze_Selected_Component).
16956 if not Is_Tagged_Type (Original_Scope) then
16957 return not Has_Private_Ancestor (Original_Scope)
16958 or else In_Open_Scopes (Scope (Original_Scope))
16959 or else In_Instance
16960 or else (Ekind (Original_Comp) = E_Discriminant
16961 and then Original_Scope = Type_Scope);
16963 -- If it is _Parent or _Tag, there is no visibility issue
16965 elsif not Comes_From_Source (Original_Comp) then
16968 -- Discriminants are visible unless the (private) type has unknown
16969 -- discriminants. If the discriminant reference is inserted for a
16970 -- discriminant check on a full view it is also visible.
16972 elsif Ekind (Original_Comp) = E_Discriminant
16974 (not Has_Unknown_Discriminants (Original_Scope)
16975 or else (Present (N)
16976 and then Nkind (N) = N_Selected_Component
16977 and then Nkind (Prefix (N)) = N_Type_Conversion
16978 and then not Comes_From_Source (Prefix (N))))
16982 -- In the body of an instantiation, no need to check for the visibility
16985 elsif In_Instance_Body then
16988 -- If the component has been declared in an ancestor which is currently
16989 -- a private type, then it is not visible. The same applies if the
16990 -- component's containing type is not in an open scope and the original
16991 -- component's enclosing type is a visible full view of a private type
16992 -- (which can occur in cases where an attempt is being made to reference
16993 -- a component in a sibling package that is inherited from a visible
16994 -- component of a type in an ancestor package; the component in the
16995 -- sibling package should not be visible even though the component it
16996 -- inherited from is visible). This does not apply however in the case
16997 -- where the scope of the type is a private child unit, or when the
16998 -- parent comes from a local package in which the ancestor is currently
16999 -- visible. The latter suppression of visibility is needed for cases
17000 -- that are tested in B730006.
17002 elsif Is_Private_Type (Original_Scope)
17004 (not Is_Private_Descendant (Type_Scope)
17005 and then not In_Open_Scopes (Type_Scope)
17006 and then Has_Private_Declaration (Original_Scope))
17008 -- If the type derives from an entity in a formal package, there
17009 -- are no additional visible components.
17011 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17012 N_Formal_Package_Declaration
17016 -- if we are not in the private part of the current package, there
17017 -- are no additional visible components.
17019 elsif Ekind (Scope (Current_Scope)) = E_Package
17020 and then not In_Private_Part (Scope (Current_Scope))
17025 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17026 and then In_Open_Scopes (Scope (Original_Scope))
17027 and then Is_Local_Type (Type_Scope);
17030 -- There is another weird way in which a component may be invisible when
17031 -- the private and the full view are not derived from the same ancestor.
17032 -- Here is an example :
17034 -- type A1 is tagged record F1 : integer; end record;
17035 -- type A2 is new A1 with record F2 : integer; end record;
17036 -- type T is new A1 with private;
17038 -- type T is new A2 with null record;
17040 -- In this case, the full view of T inherits F1 and F2 but the private
17041 -- view inherits only F1
17045 Ancestor : Entity_Id := Scope (C);
17049 if Ancestor = Original_Scope then
17051 elsif Ancestor = Etype (Ancestor) then
17055 Ancestor := Etype (Ancestor);
17059 end Is_Visible_Component;
17061 --------------------------
17062 -- Make_Class_Wide_Type --
17063 --------------------------
17065 procedure Make_Class_Wide_Type (T : Entity_Id) is
17066 CW_Type : Entity_Id;
17068 Next_E : Entity_Id;
17071 if Present (Class_Wide_Type (T)) then
17073 -- The class-wide type is a partially decorated entity created for a
17074 -- unanalyzed tagged type referenced through a limited with clause.
17075 -- When the tagged type is analyzed, its class-wide type needs to be
17076 -- redecorated. Note that we reuse the entity created by Decorate_
17077 -- Tagged_Type in order to preserve all links.
17079 if Materialize_Entity (Class_Wide_Type (T)) then
17080 CW_Type := Class_Wide_Type (T);
17081 Set_Materialize_Entity (CW_Type, False);
17083 -- The class wide type can have been defined by the partial view, in
17084 -- which case everything is already done.
17090 -- Default case, we need to create a new class-wide type
17094 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17097 -- Inherit root type characteristics
17099 CW_Name := Chars (CW_Type);
17100 Next_E := Next_Entity (CW_Type);
17101 Copy_Node (T, CW_Type);
17102 Set_Comes_From_Source (CW_Type, False);
17103 Set_Chars (CW_Type, CW_Name);
17104 Set_Parent (CW_Type, Parent (T));
17105 Set_Next_Entity (CW_Type, Next_E);
17107 -- Ensure we have a new freeze node for the class-wide type. The partial
17108 -- view may have freeze action of its own, requiring a proper freeze
17109 -- node, and the same freeze node cannot be shared between the two
17112 Set_Has_Delayed_Freeze (CW_Type);
17113 Set_Freeze_Node (CW_Type, Empty);
17115 -- Customize the class-wide type: It has no prim. op., it cannot be
17116 -- abstract and its Etype points back to the specific root type.
17118 Set_Ekind (CW_Type, E_Class_Wide_Type);
17119 Set_Is_Tagged_Type (CW_Type, True);
17120 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17121 Set_Is_Abstract_Type (CW_Type, False);
17122 Set_Is_Constrained (CW_Type, False);
17123 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17124 Set_Default_SSO (CW_Type);
17126 if Ekind (T) = E_Class_Wide_Subtype then
17127 Set_Etype (CW_Type, Etype (Base_Type (T)));
17129 Set_Etype (CW_Type, T);
17132 -- If this is the class_wide type of a constrained subtype, it does
17133 -- not have discriminants.
17135 Set_Has_Discriminants (CW_Type,
17136 Has_Discriminants (T) and then not Is_Constrained (T));
17138 Set_Has_Unknown_Discriminants (CW_Type, True);
17139 Set_Class_Wide_Type (T, CW_Type);
17140 Set_Equivalent_Type (CW_Type, Empty);
17142 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17144 Set_Class_Wide_Type (CW_Type, CW_Type);
17145 end Make_Class_Wide_Type;
17151 procedure Make_Index
17153 Related_Nod : Node_Id;
17154 Related_Id : Entity_Id := Empty;
17155 Suffix_Index : Nat := 1;
17156 In_Iter_Schm : Boolean := False)
17160 Def_Id : Entity_Id := Empty;
17161 Found : Boolean := False;
17164 -- For a discrete range used in a constrained array definition and
17165 -- defined by a range, an implicit conversion to the predefined type
17166 -- INTEGER is assumed if each bound is either a numeric literal, a named
17167 -- number, or an attribute, and the type of both bounds (prior to the
17168 -- implicit conversion) is the type universal_integer. Otherwise, both
17169 -- bounds must be of the same discrete type, other than universal
17170 -- integer; this type must be determinable independently of the
17171 -- context, but using the fact that the type must be discrete and that
17172 -- both bounds must have the same type.
17174 -- Character literals also have a universal type in the absence of
17175 -- of additional context, and are resolved to Standard_Character.
17177 if Nkind (N) = N_Range then
17179 -- The index is given by a range constraint. The bounds are known
17180 -- to be of a consistent type.
17182 if not Is_Overloaded (N) then
17185 -- For universal bounds, choose the specific predefined type
17187 if T = Universal_Integer then
17188 T := Standard_Integer;
17190 elsif T = Any_Character then
17191 Ambiguous_Character (Low_Bound (N));
17193 T := Standard_Character;
17196 -- The node may be overloaded because some user-defined operators
17197 -- are available, but if a universal interpretation exists it is
17198 -- also the selected one.
17200 elsif Universal_Interpretation (N) = Universal_Integer then
17201 T := Standard_Integer;
17207 Ind : Interp_Index;
17211 Get_First_Interp (N, Ind, It);
17212 while Present (It.Typ) loop
17213 if Is_Discrete_Type (It.Typ) then
17216 and then not Covers (It.Typ, T)
17217 and then not Covers (T, It.Typ)
17219 Error_Msg_N ("ambiguous bounds in discrete range", N);
17227 Get_Next_Interp (Ind, It);
17230 if T = Any_Type then
17231 Error_Msg_N ("discrete type required for range", N);
17232 Set_Etype (N, Any_Type);
17235 elsif T = Universal_Integer then
17236 T := Standard_Integer;
17241 if not Is_Discrete_Type (T) then
17242 Error_Msg_N ("discrete type required for range", N);
17243 Set_Etype (N, Any_Type);
17247 if Nkind (Low_Bound (N)) = N_Attribute_Reference
17248 and then Attribute_Name (Low_Bound (N)) = Name_First
17249 and then Is_Entity_Name (Prefix (Low_Bound (N)))
17250 and then Is_Type (Entity (Prefix (Low_Bound (N))))
17251 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
17253 -- The type of the index will be the type of the prefix, as long
17254 -- as the upper bound is 'Last of the same type.
17256 Def_Id := Entity (Prefix (Low_Bound (N)));
17258 if Nkind (High_Bound (N)) /= N_Attribute_Reference
17259 or else Attribute_Name (High_Bound (N)) /= Name_Last
17260 or else not Is_Entity_Name (Prefix (High_Bound (N)))
17261 or else Entity (Prefix (High_Bound (N))) /= Def_Id
17268 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
17270 elsif Nkind (N) = N_Subtype_Indication then
17272 -- The index is given by a subtype with a range constraint
17274 T := Base_Type (Entity (Subtype_Mark (N)));
17276 if not Is_Discrete_Type (T) then
17277 Error_Msg_N ("discrete type required for range", N);
17278 Set_Etype (N, Any_Type);
17282 R := Range_Expression (Constraint (N));
17285 Process_Range_Expr_In_Decl
17286 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
17288 elsif Nkind (N) = N_Attribute_Reference then
17290 -- Catch beginner's error (use of attribute other than 'Range)
17292 if Attribute_Name (N) /= Name_Range then
17293 Error_Msg_N ("expect attribute ''Range", N);
17294 Set_Etype (N, Any_Type);
17298 -- If the node denotes the range of a type mark, that is also the
17299 -- resulting type, and we do not need to create an Itype for it.
17301 if Is_Entity_Name (Prefix (N))
17302 and then Comes_From_Source (N)
17303 and then Is_Type (Entity (Prefix (N)))
17304 and then Is_Discrete_Type (Entity (Prefix (N)))
17306 Def_Id := Entity (Prefix (N));
17309 Analyze_And_Resolve (N);
17313 -- If none of the above, must be a subtype. We convert this to a
17314 -- range attribute reference because in the case of declared first
17315 -- named subtypes, the types in the range reference can be different
17316 -- from the type of the entity. A range attribute normalizes the
17317 -- reference and obtains the correct types for the bounds.
17319 -- This transformation is in the nature of an expansion, is only
17320 -- done if expansion is active. In particular, it is not done on
17321 -- formal generic types, because we need to retain the name of the
17322 -- original index for instantiation purposes.
17325 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
17326 Error_Msg_N ("invalid subtype mark in discrete range ", N);
17327 Set_Etype (N, Any_Integer);
17331 -- The type mark may be that of an incomplete type. It is only
17332 -- now that we can get the full view, previous analysis does
17333 -- not look specifically for a type mark.
17335 Set_Entity (N, Get_Full_View (Entity (N)));
17336 Set_Etype (N, Entity (N));
17337 Def_Id := Entity (N);
17339 if not Is_Discrete_Type (Def_Id) then
17340 Error_Msg_N ("discrete type required for index", N);
17341 Set_Etype (N, Any_Type);
17346 if Expander_Active then
17348 Make_Attribute_Reference (Sloc (N),
17349 Attribute_Name => Name_Range,
17350 Prefix => Relocate_Node (N)));
17352 -- The original was a subtype mark that does not freeze. This
17353 -- means that the rewritten version must not freeze either.
17355 Set_Must_Not_Freeze (N);
17356 Set_Must_Not_Freeze (Prefix (N));
17357 Analyze_And_Resolve (N);
17361 -- If expander is inactive, type is legal, nothing else to construct
17368 if not Is_Discrete_Type (T) then
17369 Error_Msg_N ("discrete type required for range", N);
17370 Set_Etype (N, Any_Type);
17373 elsif T = Any_Type then
17374 Set_Etype (N, Any_Type);
17378 -- We will now create the appropriate Itype to describe the range, but
17379 -- first a check. If we originally had a subtype, then we just label
17380 -- the range with this subtype. Not only is there no need to construct
17381 -- a new subtype, but it is wrong to do so for two reasons:
17383 -- 1. A legality concern, if we have a subtype, it must not freeze,
17384 -- and the Itype would cause freezing incorrectly
17386 -- 2. An efficiency concern, if we created an Itype, it would not be
17387 -- recognized as the same type for the purposes of eliminating
17388 -- checks in some circumstances.
17390 -- We signal this case by setting the subtype entity in Def_Id
17392 if No (Def_Id) then
17394 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
17395 Set_Etype (Def_Id, Base_Type (T));
17397 if Is_Signed_Integer_Type (T) then
17398 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
17400 elsif Is_Modular_Integer_Type (T) then
17401 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
17404 Set_Ekind (Def_Id, E_Enumeration_Subtype);
17405 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
17406 Set_First_Literal (Def_Id, First_Literal (T));
17409 Set_Size_Info (Def_Id, (T));
17410 Set_RM_Size (Def_Id, RM_Size (T));
17411 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
17413 Set_Scalar_Range (Def_Id, R);
17414 Conditional_Delay (Def_Id, T);
17416 -- In the subtype indication case, if the immediate parent of the
17417 -- new subtype is non-static, then the subtype we create is non-
17418 -- static, even if its bounds are static.
17420 if Nkind (N) = N_Subtype_Indication
17421 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
17423 Set_Is_Non_Static_Subtype (Def_Id);
17427 -- Final step is to label the index with this constructed type
17429 Set_Etype (N, Def_Id);
17432 ------------------------------
17433 -- Modular_Type_Declaration --
17434 ------------------------------
17436 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17437 Mod_Expr : constant Node_Id := Expression (Def);
17440 procedure Set_Modular_Size (Bits : Int);
17441 -- Sets RM_Size to Bits, and Esize to normal word size above this
17443 ----------------------
17444 -- Set_Modular_Size --
17445 ----------------------
17447 procedure Set_Modular_Size (Bits : Int) is
17449 Set_RM_Size (T, UI_From_Int (Bits));
17454 elsif Bits <= 16 then
17455 Init_Esize (T, 16);
17457 elsif Bits <= 32 then
17458 Init_Esize (T, 32);
17461 Init_Esize (T, System_Max_Binary_Modulus_Power);
17464 if not Non_Binary_Modulus (T)
17465 and then Esize (T) = RM_Size (T)
17467 Set_Is_Known_Valid (T);
17469 end Set_Modular_Size;
17471 -- Start of processing for Modular_Type_Declaration
17474 -- If the mod expression is (exactly) 2 * literal, where literal is
17475 -- 64 or less,then almost certainly the * was meant to be **. Warn.
17477 if Warn_On_Suspicious_Modulus_Value
17478 and then Nkind (Mod_Expr) = N_Op_Multiply
17479 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
17480 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
17481 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
17482 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
17485 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
17488 -- Proceed with analysis of mod expression
17490 Analyze_And_Resolve (Mod_Expr, Any_Integer);
17492 Set_Ekind (T, E_Modular_Integer_Type);
17493 Init_Alignment (T);
17494 Set_Is_Constrained (T);
17496 if not Is_OK_Static_Expression (Mod_Expr) then
17497 Flag_Non_Static_Expr
17498 ("non-static expression used for modular type bound!", Mod_Expr);
17499 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17501 M_Val := Expr_Value (Mod_Expr);
17505 Error_Msg_N ("modulus value must be positive", Mod_Expr);
17506 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17509 if M_Val > 2 ** Standard_Long_Integer_Size then
17510 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
17513 Set_Modulus (T, M_Val);
17515 -- Create bounds for the modular type based on the modulus given in
17516 -- the type declaration and then analyze and resolve those bounds.
17518 Set_Scalar_Range (T,
17519 Make_Range (Sloc (Mod_Expr),
17520 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
17521 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
17523 -- Properly analyze the literals for the range. We do this manually
17524 -- because we can't go calling Resolve, since we are resolving these
17525 -- bounds with the type, and this type is certainly not complete yet.
17527 Set_Etype (Low_Bound (Scalar_Range (T)), T);
17528 Set_Etype (High_Bound (Scalar_Range (T)), T);
17529 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
17530 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
17532 -- Loop through powers of two to find number of bits required
17534 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
17538 if M_Val = 2 ** Bits then
17539 Set_Modular_Size (Bits);
17544 elsif M_Val < 2 ** Bits then
17545 Check_SPARK_Restriction ("modulus should be a power of 2", T);
17546 Set_Non_Binary_Modulus (T);
17548 if Bits > System_Max_Nonbinary_Modulus_Power then
17549 Error_Msg_Uint_1 :=
17550 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
17552 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
17553 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17557 -- In the non-binary case, set size as per RM 13.3(55)
17559 Set_Modular_Size (Bits);
17566 -- If we fall through, then the size exceed System.Max_Binary_Modulus
17567 -- so we just signal an error and set the maximum size.
17569 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
17570 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
17572 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17573 Init_Alignment (T);
17575 end Modular_Type_Declaration;
17577 --------------------------
17578 -- New_Concatenation_Op --
17579 --------------------------
17581 procedure New_Concatenation_Op (Typ : Entity_Id) is
17582 Loc : constant Source_Ptr := Sloc (Typ);
17585 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
17586 -- Create abbreviated declaration for the formal of a predefined
17587 -- Operator 'Op' of type 'Typ'
17589 --------------------
17590 -- Make_Op_Formal --
17591 --------------------
17593 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
17594 Formal : Entity_Id;
17596 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
17597 Set_Etype (Formal, Typ);
17598 Set_Mechanism (Formal, Default_Mechanism);
17600 end Make_Op_Formal;
17602 -- Start of processing for New_Concatenation_Op
17605 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
17607 Set_Ekind (Op, E_Operator);
17608 Set_Scope (Op, Current_Scope);
17609 Set_Etype (Op, Typ);
17610 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
17611 Set_Is_Immediately_Visible (Op);
17612 Set_Is_Intrinsic_Subprogram (Op);
17613 Set_Has_Completion (Op);
17614 Append_Entity (Op, Current_Scope);
17616 Set_Name_Entity_Id (Name_Op_Concat, Op);
17618 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17619 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17620 end New_Concatenation_Op;
17622 -------------------------
17623 -- OK_For_Limited_Init --
17624 -------------------------
17626 -- ???Check all calls of this, and compare the conditions under which it's
17629 function OK_For_Limited_Init
17631 Exp : Node_Id) return Boolean
17634 return Is_CPP_Constructor_Call (Exp)
17635 or else (Ada_Version >= Ada_2005
17636 and then not Debug_Flag_Dot_L
17637 and then OK_For_Limited_Init_In_05 (Typ, Exp));
17638 end OK_For_Limited_Init;
17640 -------------------------------
17641 -- OK_For_Limited_Init_In_05 --
17642 -------------------------------
17644 function OK_For_Limited_Init_In_05
17646 Exp : Node_Id) return Boolean
17649 -- An object of a limited interface type can be initialized with any
17650 -- expression of a nonlimited descendant type.
17652 if Is_Class_Wide_Type (Typ)
17653 and then Is_Limited_Interface (Typ)
17654 and then not Is_Limited_Type (Etype (Exp))
17659 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
17660 -- case of limited aggregates (including extension aggregates), and
17661 -- function calls. The function call may have been given in prefixed
17662 -- notation, in which case the original node is an indexed component.
17663 -- If the function is parameterless, the original node was an explicit
17664 -- dereference. The function may also be parameterless, in which case
17665 -- the source node is just an identifier.
17667 case Nkind (Original_Node (Exp)) is
17668 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
17671 when N_Identifier =>
17672 return Present (Entity (Original_Node (Exp)))
17673 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
17675 when N_Qualified_Expression =>
17677 OK_For_Limited_Init_In_05
17678 (Typ, Expression (Original_Node (Exp)));
17680 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
17681 -- with a function call, the expander has rewritten the call into an
17682 -- N_Type_Conversion node to force displacement of the pointer to
17683 -- reference the component containing the secondary dispatch table.
17684 -- Otherwise a type conversion is not a legal context.
17685 -- A return statement for a build-in-place function returning a
17686 -- synchronized type also introduces an unchecked conversion.
17688 when N_Type_Conversion |
17689 N_Unchecked_Type_Conversion =>
17690 return not Comes_From_Source (Exp)
17692 OK_For_Limited_Init_In_05
17693 (Typ, Expression (Original_Node (Exp)));
17695 when N_Indexed_Component |
17696 N_Selected_Component |
17697 N_Explicit_Dereference =>
17698 return Nkind (Exp) = N_Function_Call;
17700 -- A use of 'Input is a function call, hence allowed. Normally the
17701 -- attribute will be changed to a call, but the attribute by itself
17702 -- can occur with -gnatc.
17704 when N_Attribute_Reference =>
17705 return Attribute_Name (Original_Node (Exp)) = Name_Input;
17707 -- For a case expression, all dependent expressions must be legal
17709 when N_Case_Expression =>
17714 Alt := First (Alternatives (Original_Node (Exp)));
17715 while Present (Alt) loop
17716 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
17726 -- For an if expression, all dependent expressions must be legal
17728 when N_If_Expression =>
17730 Then_Expr : constant Node_Id :=
17731 Next (First (Expressions (Original_Node (Exp))));
17732 Else_Expr : constant Node_Id := Next (Then_Expr);
17734 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
17736 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
17742 end OK_For_Limited_Init_In_05;
17744 -------------------------------------------
17745 -- Ordinary_Fixed_Point_Type_Declaration --
17746 -------------------------------------------
17748 procedure Ordinary_Fixed_Point_Type_Declaration
17752 Loc : constant Source_Ptr := Sloc (Def);
17753 Delta_Expr : constant Node_Id := Delta_Expression (Def);
17754 RRS : constant Node_Id := Real_Range_Specification (Def);
17755 Implicit_Base : Entity_Id;
17762 Check_Restriction (No_Fixed_Point, Def);
17764 -- Create implicit base type
17767 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
17768 Set_Etype (Implicit_Base, Implicit_Base);
17770 -- Analyze and process delta expression
17772 Analyze_And_Resolve (Delta_Expr, Any_Real);
17774 Check_Delta_Expression (Delta_Expr);
17775 Delta_Val := Expr_Value_R (Delta_Expr);
17777 Set_Delta_Value (Implicit_Base, Delta_Val);
17779 -- Compute default small from given delta, which is the largest power
17780 -- of two that does not exceed the given delta value.
17790 if Delta_Val < Ureal_1 then
17791 while Delta_Val < Tmp loop
17792 Tmp := Tmp / Ureal_2;
17793 Scale := Scale + 1;
17798 Tmp := Tmp * Ureal_2;
17799 exit when Tmp > Delta_Val;
17800 Scale := Scale - 1;
17804 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
17807 Set_Small_Value (Implicit_Base, Small_Val);
17809 -- If no range was given, set a dummy range
17811 if RRS <= Empty_Or_Error then
17812 Low_Val := -Small_Val;
17813 High_Val := Small_Val;
17815 -- Otherwise analyze and process given range
17819 Low : constant Node_Id := Low_Bound (RRS);
17820 High : constant Node_Id := High_Bound (RRS);
17823 Analyze_And_Resolve (Low, Any_Real);
17824 Analyze_And_Resolve (High, Any_Real);
17825 Check_Real_Bound (Low);
17826 Check_Real_Bound (High);
17828 -- Obtain and set the range
17830 Low_Val := Expr_Value_R (Low);
17831 High_Val := Expr_Value_R (High);
17833 if Low_Val > High_Val then
17834 Error_Msg_NE ("??fixed point type& has null range", Def, T);
17839 -- The range for both the implicit base and the declared first subtype
17840 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
17841 -- set a temporary range in place. Note that the bounds of the base
17842 -- type will be widened to be symmetrical and to fill the available
17843 -- bits when the type is frozen.
17845 -- We could do this with all discrete types, and probably should, but
17846 -- we absolutely have to do it for fixed-point, since the end-points
17847 -- of the range and the size are determined by the small value, which
17848 -- could be reset before the freeze point.
17850 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
17851 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
17853 -- Complete definition of first subtype
17855 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
17856 Set_Etype (T, Implicit_Base);
17857 Init_Size_Align (T);
17858 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
17859 Set_Small_Value (T, Small_Val);
17860 Set_Delta_Value (T, Delta_Val);
17861 Set_Is_Constrained (T);
17863 end Ordinary_Fixed_Point_Type_Declaration;
17865 ----------------------------------------
17866 -- Prepare_Private_Subtype_Completion --
17867 ----------------------------------------
17869 procedure Prepare_Private_Subtype_Completion
17871 Related_Nod : Node_Id)
17873 Id_B : constant Entity_Id := Base_Type (Id);
17874 Full_B : constant Entity_Id := Full_View (Id_B);
17878 if Present (Full_B) then
17880 -- The Base_Type is already completed, we can complete the subtype
17881 -- now. We have to create a new entity with the same name, Thus we
17882 -- can't use Create_Itype.
17884 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
17885 Set_Is_Itype (Full);
17886 Set_Associated_Node_For_Itype (Full, Related_Nod);
17887 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
17890 -- The parent subtype may be private, but the base might not, in some
17891 -- nested instances. In that case, the subtype does not need to be
17892 -- exchanged. It would still be nice to make private subtypes and their
17893 -- bases consistent at all times ???
17895 if Is_Private_Type (Id_B) then
17896 Append_Elmt (Id, Private_Dependents (Id_B));
17898 end Prepare_Private_Subtype_Completion;
17900 ---------------------------
17901 -- Process_Discriminants --
17902 ---------------------------
17904 procedure Process_Discriminants
17906 Prev : Entity_Id := Empty)
17908 Elist : constant Elist_Id := New_Elmt_List;
17911 Discr_Number : Uint;
17912 Discr_Type : Entity_Id;
17913 Default_Present : Boolean := False;
17914 Default_Not_Present : Boolean := False;
17917 -- A composite type other than an array type can have discriminants.
17918 -- On entry, the current scope is the composite type.
17920 -- The discriminants are initially entered into the scope of the type
17921 -- via Enter_Name with the default Ekind of E_Void to prevent premature
17922 -- use, as explained at the end of this procedure.
17924 Discr := First (Discriminant_Specifications (N));
17925 while Present (Discr) loop
17926 Enter_Name (Defining_Identifier (Discr));
17928 -- For navigation purposes we add a reference to the discriminant
17929 -- in the entity for the type. If the current declaration is a
17930 -- completion, place references on the partial view. Otherwise the
17931 -- type is the current scope.
17933 if Present (Prev) then
17935 -- The references go on the partial view, if present. If the
17936 -- partial view has discriminants, the references have been
17937 -- generated already.
17939 if not Has_Discriminants (Prev) then
17940 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17944 (Current_Scope, Defining_Identifier (Discr), 'd');
17947 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17948 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17950 -- Ada 2005 (AI-254)
17952 if Present (Access_To_Subprogram_Definition
17953 (Discriminant_Type (Discr)))
17954 and then Protected_Present (Access_To_Subprogram_Definition
17955 (Discriminant_Type (Discr)))
17958 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17962 Find_Type (Discriminant_Type (Discr));
17963 Discr_Type := Etype (Discriminant_Type (Discr));
17965 if Error_Posted (Discriminant_Type (Discr)) then
17966 Discr_Type := Any_Type;
17970 if Is_Access_Type (Discr_Type) then
17972 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17975 if Ada_Version < Ada_2005 then
17976 Check_Access_Discriminant_Requires_Limited
17977 (Discr, Discriminant_Type (Discr));
17980 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17982 ("(Ada 83) access discriminant not allowed", Discr);
17985 elsif not Is_Discrete_Type (Discr_Type) then
17986 Error_Msg_N ("discriminants must have a discrete or access type",
17987 Discriminant_Type (Discr));
17990 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17992 -- If a discriminant specification includes the assignment compound
17993 -- delimiter followed by an expression, the expression is the default
17994 -- expression of the discriminant; the default expression must be of
17995 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17996 -- a default expression, we do the special preanalysis, since this
17997 -- expression does not freeze (see "Handling of Default and Per-
17998 -- Object Expressions" in spec of package Sem).
18000 if Present (Expression (Discr)) then
18001 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18003 if Nkind (N) = N_Formal_Type_Declaration then
18005 ("discriminant defaults not allowed for formal type",
18006 Expression (Discr));
18008 -- Flag an error for a tagged type with defaulted discriminants,
18009 -- excluding limited tagged types when compiling for Ada 2012
18010 -- (see AI05-0214).
18012 elsif Is_Tagged_Type (Current_Scope)
18013 and then (not Is_Limited_Type (Current_Scope)
18014 or else Ada_Version < Ada_2012)
18015 and then Comes_From_Source (N)
18017 -- Note: see similar test in Check_Or_Process_Discriminants, to
18018 -- handle the (illegal) case of the completion of an untagged
18019 -- view with discriminants with defaults by a tagged full view.
18020 -- We skip the check if Discr does not come from source, to
18021 -- account for the case of an untagged derived type providing
18022 -- defaults for a renamed discriminant from a private untagged
18023 -- ancestor with a tagged full view (ACATS B460006).
18025 if Ada_Version >= Ada_2012 then
18027 ("discriminants of nonlimited tagged type cannot have"
18029 Expression (Discr));
18032 ("discriminants of tagged type cannot have defaults",
18033 Expression (Discr));
18037 Default_Present := True;
18038 Append_Elmt (Expression (Discr), Elist);
18040 -- Tag the defining identifiers for the discriminants with
18041 -- their corresponding default expressions from the tree.
18043 Set_Discriminant_Default_Value
18044 (Defining_Identifier (Discr), Expression (Discr));
18048 Default_Not_Present := True;
18051 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
18052 -- Discr_Type but with the null-exclusion attribute
18054 if Ada_Version >= Ada_2005 then
18056 -- Ada 2005 (AI-231): Static checks
18058 if Can_Never_Be_Null (Discr_Type) then
18059 Null_Exclusion_Static_Checks (Discr);
18061 elsif Is_Access_Type (Discr_Type)
18062 and then Null_Exclusion_Present (Discr)
18064 -- No need to check itypes because in their case this check
18065 -- was done at their point of creation
18067 and then not Is_Itype (Discr_Type)
18069 if Can_Never_Be_Null (Discr_Type) then
18071 ("`NOT NULL` not allowed (& already excludes null)",
18076 Set_Etype (Defining_Identifier (Discr),
18077 Create_Null_Excluding_Itype
18079 Related_Nod => Discr));
18081 -- Check for improper null exclusion if the type is otherwise
18082 -- legal for a discriminant.
18084 elsif Null_Exclusion_Present (Discr)
18085 and then Is_Discrete_Type (Discr_Type)
18088 ("null exclusion can only apply to an access type", Discr);
18091 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18092 -- can't have defaults. Synchronized types, or types that are
18093 -- explicitly limited are fine, but special tests apply to derived
18094 -- types in generics: in a generic body we have to assume the
18095 -- worst, and therefore defaults are not allowed if the parent is
18096 -- a generic formal private type (see ACATS B370001).
18098 if Is_Access_Type (Discr_Type) and then Default_Present then
18099 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18100 or else Is_Limited_Record (Current_Scope)
18101 or else Is_Concurrent_Type (Current_Scope)
18102 or else Is_Concurrent_Record_Type (Current_Scope)
18103 or else Ekind (Current_Scope) = E_Limited_Private_Type
18105 if not Is_Derived_Type (Current_Scope)
18106 or else not Is_Generic_Type (Etype (Current_Scope))
18107 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18108 or else Limited_Present
18109 (Type_Definition (Parent (Current_Scope)))
18114 Error_Msg_N ("access discriminants of nonlimited types",
18115 Expression (Discr));
18116 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18119 elsif Present (Expression (Discr)) then
18121 ("(Ada 2005) access discriminants of nonlimited types",
18122 Expression (Discr));
18123 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18128 -- A discriminant cannot be effectively volatile. This check is only
18129 -- relevant when SPARK_Mode is on as it is not standard Ada legality
18130 -- rule (SPARK RM 7.1.3(6)).
18133 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
18135 Error_Msg_N ("discriminant cannot be volatile", Discr);
18141 -- An element list consisting of the default expressions of the
18142 -- discriminants is constructed in the above loop and used to set
18143 -- the Discriminant_Constraint attribute for the type. If an object
18144 -- is declared of this (record or task) type without any explicit
18145 -- discriminant constraint given, this element list will form the
18146 -- actual parameters for the corresponding initialization procedure
18149 Set_Discriminant_Constraint (Current_Scope, Elist);
18150 Set_Stored_Constraint (Current_Scope, No_Elist);
18152 -- Default expressions must be provided either for all or for none
18153 -- of the discriminants of a discriminant part. (RM 3.7.1)
18155 if Default_Present and then Default_Not_Present then
18157 ("incomplete specification of defaults for discriminants", N);
18160 -- The use of the name of a discriminant is not allowed in default
18161 -- expressions of a discriminant part if the specification of the
18162 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
18164 -- To detect this, the discriminant names are entered initially with an
18165 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
18166 -- attempt to use a void entity (for example in an expression that is
18167 -- type-checked) produces the error message: premature usage. Now after
18168 -- completing the semantic analysis of the discriminant part, we can set
18169 -- the Ekind of all the discriminants appropriately.
18171 Discr := First (Discriminant_Specifications (N));
18172 Discr_Number := Uint_1;
18173 while Present (Discr) loop
18174 Id := Defining_Identifier (Discr);
18175 Set_Ekind (Id, E_Discriminant);
18176 Init_Component_Location (Id);
18178 Set_Discriminant_Number (Id, Discr_Number);
18180 -- Make sure this is always set, even in illegal programs
18182 Set_Corresponding_Discriminant (Id, Empty);
18184 -- Initialize the Original_Record_Component to the entity itself.
18185 -- Inherit_Components will propagate the right value to
18186 -- discriminants in derived record types.
18188 Set_Original_Record_Component (Id, Id);
18190 -- Create the discriminal for the discriminant
18192 Build_Discriminal (Id);
18195 Discr_Number := Discr_Number + 1;
18198 Set_Has_Discriminants (Current_Scope);
18199 end Process_Discriminants;
18201 -----------------------
18202 -- Process_Full_View --
18203 -----------------------
18205 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
18206 Priv_Parent : Entity_Id;
18207 Full_Parent : Entity_Id;
18208 Full_Indic : Node_Id;
18210 procedure Collect_Implemented_Interfaces
18212 Ifaces : Elist_Id);
18213 -- Ada 2005: Gather all the interfaces that Typ directly or
18214 -- inherently implements. Duplicate entries are not added to
18215 -- the list Ifaces.
18217 ------------------------------------
18218 -- Collect_Implemented_Interfaces --
18219 ------------------------------------
18221 procedure Collect_Implemented_Interfaces
18226 Iface_Elmt : Elmt_Id;
18229 -- Abstract interfaces are only associated with tagged record types
18231 if not Is_Tagged_Type (Typ)
18232 or else not Is_Record_Type (Typ)
18237 -- Recursively climb to the ancestors
18239 if Etype (Typ) /= Typ
18241 -- Protect the frontend against wrong cyclic declarations like:
18243 -- type B is new A with private;
18244 -- type C is new A with private;
18246 -- type B is new C with null record;
18247 -- type C is new B with null record;
18249 and then Etype (Typ) /= Priv_T
18250 and then Etype (Typ) /= Full_T
18252 -- Keep separate the management of private type declarations
18254 if Ekind (Typ) = E_Record_Type_With_Private then
18256 -- Handle the following illegal usage:
18257 -- type Private_Type is tagged private;
18259 -- type Private_Type is new Type_Implementing_Iface;
18261 if Present (Full_View (Typ))
18262 and then Etype (Typ) /= Full_View (Typ)
18264 if Is_Interface (Etype (Typ)) then
18265 Append_Unique_Elmt (Etype (Typ), Ifaces);
18268 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18271 -- Non-private types
18274 if Is_Interface (Etype (Typ)) then
18275 Append_Unique_Elmt (Etype (Typ), Ifaces);
18278 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18282 -- Handle entities in the list of abstract interfaces
18284 if Present (Interfaces (Typ)) then
18285 Iface_Elmt := First_Elmt (Interfaces (Typ));
18286 while Present (Iface_Elmt) loop
18287 Iface := Node (Iface_Elmt);
18289 pragma Assert (Is_Interface (Iface));
18291 if not Contain_Interface (Iface, Ifaces) then
18292 Append_Elmt (Iface, Ifaces);
18293 Collect_Implemented_Interfaces (Iface, Ifaces);
18296 Next_Elmt (Iface_Elmt);
18299 end Collect_Implemented_Interfaces;
18301 -- Start of processing for Process_Full_View
18304 -- First some sanity checks that must be done after semantic
18305 -- decoration of the full view and thus cannot be placed with other
18306 -- similar checks in Find_Type_Name
18308 if not Is_Limited_Type (Priv_T)
18309 and then (Is_Limited_Type (Full_T)
18310 or else Is_Limited_Composite (Full_T))
18312 if In_Instance then
18316 ("completion of nonlimited type cannot be limited", Full_T);
18317 Explain_Limited_Type (Full_T, Full_T);
18320 elsif Is_Abstract_Type (Full_T)
18321 and then not Is_Abstract_Type (Priv_T)
18324 ("completion of nonabstract type cannot be abstract", Full_T);
18326 elsif Is_Tagged_Type (Priv_T)
18327 and then Is_Limited_Type (Priv_T)
18328 and then not Is_Limited_Type (Full_T)
18330 -- If pragma CPP_Class was applied to the private declaration
18331 -- propagate the limitedness to the full-view
18333 if Is_CPP_Class (Priv_T) then
18334 Set_Is_Limited_Record (Full_T);
18336 -- GNAT allow its own definition of Limited_Controlled to disobey
18337 -- this rule in order in ease the implementation. This test is safe
18338 -- because Root_Controlled is defined in a child of System that
18339 -- normal programs are not supposed to use.
18341 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
18342 Set_Is_Limited_Composite (Full_T);
18345 ("completion of limited tagged type must be limited", Full_T);
18348 elsif Is_Generic_Type (Priv_T) then
18349 Error_Msg_N ("generic type cannot have a completion", Full_T);
18352 -- Check that ancestor interfaces of private and full views are
18353 -- consistent. We omit this check for synchronized types because
18354 -- they are performed on the corresponding record type when frozen.
18356 if Ada_Version >= Ada_2005
18357 and then Is_Tagged_Type (Priv_T)
18358 and then Is_Tagged_Type (Full_T)
18359 and then not Is_Concurrent_Type (Full_T)
18363 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
18364 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
18367 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
18368 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
18370 -- Ada 2005 (AI-251): The partial view shall be a descendant of
18371 -- an interface type if and only if the full type is descendant
18372 -- of the interface type (AARM 7.3 (7.3/2)).
18374 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
18376 if Present (Iface) then
18378 ("interface in partial view& not implemented by full type "
18379 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18382 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
18384 if Present (Iface) then
18386 ("interface & not implemented by partial view "
18387 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18392 if Is_Tagged_Type (Priv_T)
18393 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18394 and then Is_Derived_Type (Full_T)
18396 Priv_Parent := Etype (Priv_T);
18398 -- The full view of a private extension may have been transformed
18399 -- into an unconstrained derived type declaration and a subtype
18400 -- declaration (see build_derived_record_type for details).
18402 if Nkind (N) = N_Subtype_Declaration then
18403 Full_Indic := Subtype_Indication (N);
18404 Full_Parent := Etype (Base_Type (Full_T));
18406 Full_Indic := Subtype_Indication (Type_Definition (N));
18407 Full_Parent := Etype (Full_T);
18410 -- Check that the parent type of the full type is a descendant of
18411 -- the ancestor subtype given in the private extension. If either
18412 -- entity has an Etype equal to Any_Type then we had some previous
18413 -- error situation [7.3(8)].
18415 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
18418 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
18419 -- any order. Therefore we don't have to check that its parent must
18420 -- be a descendant of the parent of the private type declaration.
18422 elsif Is_Interface (Priv_Parent)
18423 and then Is_Interface (Full_Parent)
18427 -- Ada 2005 (AI-251): If the parent of the private type declaration
18428 -- is an interface there is no need to check that it is an ancestor
18429 -- of the associated full type declaration. The required tests for
18430 -- this case are performed by Build_Derived_Record_Type.
18432 elsif not Is_Interface (Base_Type (Priv_Parent))
18433 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
18436 ("parent of full type must descend from parent"
18437 & " of private extension", Full_Indic);
18439 -- First check a formal restriction, and then proceed with checking
18440 -- Ada rules. Since the formal restriction is not a serious error, we
18441 -- don't prevent further error detection for this check, hence the
18446 -- In formal mode, when completing a private extension the type
18447 -- named in the private part must be exactly the same as that
18448 -- named in the visible part.
18450 if Priv_Parent /= Full_Parent then
18451 Error_Msg_Name_1 := Chars (Priv_Parent);
18452 Check_SPARK_Restriction ("% expected", Full_Indic);
18455 -- Check the rules of 7.3(10): if the private extension inherits
18456 -- known discriminants, then the full type must also inherit those
18457 -- discriminants from the same (ancestor) type, and the parent
18458 -- subtype of the full type must be constrained if and only if
18459 -- the ancestor subtype of the private extension is constrained.
18461 if No (Discriminant_Specifications (Parent (Priv_T)))
18462 and then not Has_Unknown_Discriminants (Priv_T)
18463 and then Has_Discriminants (Base_Type (Priv_Parent))
18466 Priv_Indic : constant Node_Id :=
18467 Subtype_Indication (Parent (Priv_T));
18469 Priv_Constr : constant Boolean :=
18470 Is_Constrained (Priv_Parent)
18472 Nkind (Priv_Indic) = N_Subtype_Indication
18474 Is_Constrained (Entity (Priv_Indic));
18476 Full_Constr : constant Boolean :=
18477 Is_Constrained (Full_Parent)
18479 Nkind (Full_Indic) = N_Subtype_Indication
18481 Is_Constrained (Entity (Full_Indic));
18483 Priv_Discr : Entity_Id;
18484 Full_Discr : Entity_Id;
18487 Priv_Discr := First_Discriminant (Priv_Parent);
18488 Full_Discr := First_Discriminant (Full_Parent);
18489 while Present (Priv_Discr) and then Present (Full_Discr) loop
18490 if Original_Record_Component (Priv_Discr) =
18491 Original_Record_Component (Full_Discr)
18493 Corresponding_Discriminant (Priv_Discr) =
18494 Corresponding_Discriminant (Full_Discr)
18501 Next_Discriminant (Priv_Discr);
18502 Next_Discriminant (Full_Discr);
18505 if Present (Priv_Discr) or else Present (Full_Discr) then
18507 ("full view must inherit discriminants of the parent"
18508 & " type used in the private extension", Full_Indic);
18510 elsif Priv_Constr and then not Full_Constr then
18512 ("parent subtype of full type must be constrained",
18515 elsif Full_Constr and then not Priv_Constr then
18517 ("parent subtype of full type must be unconstrained",
18522 -- Check the rules of 7.3(12): if a partial view has neither
18523 -- known or unknown discriminants, then the full type
18524 -- declaration shall define a definite subtype.
18526 elsif not Has_Unknown_Discriminants (Priv_T)
18527 and then not Has_Discriminants (Priv_T)
18528 and then not Is_Constrained (Full_T)
18531 ("full view must define a constrained type if partial view"
18532 & " has no discriminants", Full_T);
18535 -- ??????? Do we implement the following properly ?????
18536 -- If the ancestor subtype of a private extension has constrained
18537 -- discriminants, then the parent subtype of the full view shall
18538 -- impose a statically matching constraint on those discriminants
18543 -- For untagged types, verify that a type without discriminants is
18544 -- not completed with an unconstrained type. A separate error message
18545 -- is produced if the full type has defaulted discriminants.
18547 if not Is_Indefinite_Subtype (Priv_T)
18548 and then Is_Indefinite_Subtype (Full_T)
18550 Error_Msg_Sloc := Sloc (Parent (Priv_T));
18552 ("full view of& not compatible with declaration#",
18555 if not Is_Tagged_Type (Full_T) then
18557 ("\one is constrained, the other unconstrained", Full_T);
18562 -- AI-419: verify that the use of "limited" is consistent
18565 Orig_Decl : constant Node_Id := Original_Node (N);
18568 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18569 and then not Limited_Present (Parent (Priv_T))
18570 and then not Synchronized_Present (Parent (Priv_T))
18571 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
18573 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
18574 and then Limited_Present (Type_Definition (Orig_Decl))
18577 ("full view of non-limited extension cannot be limited", N);
18581 -- Ada 2005 (AI-443): A synchronized private extension must be
18582 -- completed by a task or protected type.
18584 if Ada_Version >= Ada_2005
18585 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18586 and then Synchronized_Present (Parent (Priv_T))
18587 and then not Is_Concurrent_Type (Full_T)
18589 Error_Msg_N ("full view of synchronized extension must " &
18590 "be synchronized type", N);
18593 -- Ada 2005 AI-363: if the full view has discriminants with
18594 -- defaults, it is illegal to declare constrained access subtypes
18595 -- whose designated type is the current type. This allows objects
18596 -- of the type that are declared in the heap to be unconstrained.
18598 if not Has_Unknown_Discriminants (Priv_T)
18599 and then not Has_Discriminants (Priv_T)
18600 and then Has_Discriminants (Full_T)
18602 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
18604 Set_Has_Constrained_Partial_View (Full_T);
18605 Set_Has_Constrained_Partial_View (Priv_T);
18608 -- Create a full declaration for all its subtypes recorded in
18609 -- Private_Dependents and swap them similarly to the base type. These
18610 -- are subtypes that have been define before the full declaration of
18611 -- the private type. We also swap the entry in Private_Dependents list
18612 -- so we can properly restore the private view on exit from the scope.
18615 Priv_Elmt : Elmt_Id;
18616 Priv_Scop : Entity_Id;
18621 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
18622 while Present (Priv_Elmt) loop
18623 Priv := Node (Priv_Elmt);
18624 Priv_Scop := Scope (Priv);
18626 if Ekind_In (Priv, E_Private_Subtype,
18627 E_Limited_Private_Subtype,
18628 E_Record_Subtype_With_Private)
18630 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
18631 Set_Is_Itype (Full);
18632 Set_Parent (Full, Parent (Priv));
18633 Set_Associated_Node_For_Itype (Full, N);
18635 -- Now we need to complete the private subtype, but since the
18636 -- base type has already been swapped, we must also swap the
18637 -- subtypes (and thus, reverse the arguments in the call to
18638 -- Complete_Private_Subtype). Also note that we may need to
18639 -- re-establish the scope of the private subtype.
18641 Copy_And_Swap (Priv, Full);
18643 if not In_Open_Scopes (Priv_Scop) then
18644 Push_Scope (Priv_Scop);
18647 -- Reset Priv_Scop to Empty to indicate no scope was pushed
18649 Priv_Scop := Empty;
18652 Complete_Private_Subtype (Full, Priv, Full_T, N);
18654 if Present (Priv_Scop) then
18658 Replace_Elmt (Priv_Elmt, Full);
18661 Next_Elmt (Priv_Elmt);
18665 -- If the private view was tagged, copy the new primitive operations
18666 -- from the private view to the full view.
18668 if Is_Tagged_Type (Full_T) then
18670 Disp_Typ : Entity_Id;
18671 Full_List : Elist_Id;
18673 Prim_Elmt : Elmt_Id;
18674 Priv_List : Elist_Id;
18678 L : Elist_Id) return Boolean;
18679 -- Determine whether list L contains element E
18687 L : Elist_Id) return Boolean
18689 List_Elmt : Elmt_Id;
18692 List_Elmt := First_Elmt (L);
18693 while Present (List_Elmt) loop
18694 if Node (List_Elmt) = E then
18698 Next_Elmt (List_Elmt);
18704 -- Start of processing
18707 if Is_Tagged_Type (Priv_T) then
18708 Priv_List := Primitive_Operations (Priv_T);
18709 Prim_Elmt := First_Elmt (Priv_List);
18711 -- In the case of a concurrent type completing a private tagged
18712 -- type, primitives may have been declared in between the two
18713 -- views. These subprograms need to be wrapped the same way
18714 -- entries and protected procedures are handled because they
18715 -- cannot be directly shared by the two views.
18717 if Is_Concurrent_Type (Full_T) then
18719 Conc_Typ : constant Entity_Id :=
18720 Corresponding_Record_Type (Full_T);
18721 Curr_Nod : Node_Id := Parent (Conc_Typ);
18722 Wrap_Spec : Node_Id;
18725 while Present (Prim_Elmt) loop
18726 Prim := Node (Prim_Elmt);
18728 if Comes_From_Source (Prim)
18729 and then not Is_Abstract_Subprogram (Prim)
18732 Make_Subprogram_Declaration (Sloc (Prim),
18736 Obj_Typ => Conc_Typ,
18738 Parameter_Specifications (
18741 Insert_After (Curr_Nod, Wrap_Spec);
18742 Curr_Nod := Wrap_Spec;
18744 Analyze (Wrap_Spec);
18747 Next_Elmt (Prim_Elmt);
18753 -- For non-concurrent types, transfer explicit primitives, but
18754 -- omit those inherited from the parent of the private view
18755 -- since they will be re-inherited later on.
18758 Full_List := Primitive_Operations (Full_T);
18760 while Present (Prim_Elmt) loop
18761 Prim := Node (Prim_Elmt);
18763 if Comes_From_Source (Prim)
18764 and then not Contains (Prim, Full_List)
18766 Append_Elmt (Prim, Full_List);
18769 Next_Elmt (Prim_Elmt);
18773 -- Untagged private view
18776 Full_List := Primitive_Operations (Full_T);
18778 -- In this case the partial view is untagged, so here we locate
18779 -- all of the earlier primitives that need to be treated as
18780 -- dispatching (those that appear between the two views). Note
18781 -- that these additional operations must all be new operations
18782 -- (any earlier operations that override inherited operations
18783 -- of the full view will already have been inserted in the
18784 -- primitives list, marked by Check_Operation_From_Private_View
18785 -- as dispatching. Note that implicit "/=" operators are
18786 -- excluded from being added to the primitives list since they
18787 -- shouldn't be treated as dispatching (tagged "/=" is handled
18790 Prim := Next_Entity (Full_T);
18791 while Present (Prim) and then Prim /= Priv_T loop
18792 if Ekind_In (Prim, E_Procedure, E_Function) then
18793 Disp_Typ := Find_Dispatching_Type (Prim);
18795 if Disp_Typ = Full_T
18796 and then (Chars (Prim) /= Name_Op_Ne
18797 or else Comes_From_Source (Prim))
18799 Check_Controlling_Formals (Full_T, Prim);
18801 if not Is_Dispatching_Operation (Prim) then
18802 Append_Elmt (Prim, Full_List);
18803 Set_Is_Dispatching_Operation (Prim, True);
18804 Set_DT_Position (Prim, No_Uint);
18807 elsif Is_Dispatching_Operation (Prim)
18808 and then Disp_Typ /= Full_T
18811 -- Verify that it is not otherwise controlled by a
18812 -- formal or a return value of type T.
18814 Check_Controlling_Formals (Disp_Typ, Prim);
18818 Next_Entity (Prim);
18822 -- For the tagged case, the two views can share the same primitive
18823 -- operations list and the same class-wide type. Update attributes
18824 -- of the class-wide type which depend on the full declaration.
18826 if Is_Tagged_Type (Priv_T) then
18827 Set_Direct_Primitive_Operations (Priv_T, Full_List);
18828 Set_Class_Wide_Type
18829 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
18831 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
18833 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
18838 -- Ada 2005 AI 161: Check preelaborable initialization consistency
18840 if Known_To_Have_Preelab_Init (Priv_T) then
18842 -- Case where there is a pragma Preelaborable_Initialization. We
18843 -- always allow this in predefined units, which is cheating a bit,
18844 -- but it means we don't have to struggle to meet the requirements in
18845 -- the RM for having Preelaborable Initialization. Otherwise we
18846 -- require that the type meets the RM rules. But we can't check that
18847 -- yet, because of the rule about overriding Initialize, so we simply
18848 -- set a flag that will be checked at freeze time.
18850 if not In_Predefined_Unit (Full_T) then
18851 Set_Must_Have_Preelab_Init (Full_T);
18855 -- If pragma CPP_Class was applied to the private type declaration,
18856 -- propagate it now to the full type declaration.
18858 if Is_CPP_Class (Priv_T) then
18859 Set_Is_CPP_Class (Full_T);
18860 Set_Convention (Full_T, Convention_CPP);
18862 -- Check that components of imported CPP types do not have default
18865 Check_CPP_Type_Has_No_Defaults (Full_T);
18868 -- If the private view has user specified stream attributes, then so has
18871 -- Why the test, how could these flags be already set in Full_T ???
18873 if Has_Specified_Stream_Read (Priv_T) then
18874 Set_Has_Specified_Stream_Read (Full_T);
18877 if Has_Specified_Stream_Write (Priv_T) then
18878 Set_Has_Specified_Stream_Write (Full_T);
18881 if Has_Specified_Stream_Input (Priv_T) then
18882 Set_Has_Specified_Stream_Input (Full_T);
18885 if Has_Specified_Stream_Output (Priv_T) then
18886 Set_Has_Specified_Stream_Output (Full_T);
18889 -- Propagate invariants to full type
18891 if Has_Invariants (Priv_T) then
18892 Set_Has_Invariants (Full_T);
18893 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
18896 if Has_Inheritable_Invariants (Priv_T) then
18897 Set_Has_Inheritable_Invariants (Full_T);
18900 -- Propagate predicates to full type, and predicate function if already
18901 -- defined. It is not clear that this can actually happen? the partial
18902 -- view cannot be frozen yet, and the predicate function has not been
18903 -- built. Still it is a cheap check and seems safer to make it.
18905 if Has_Predicates (Priv_T) then
18906 if Present (Predicate_Function (Priv_T)) then
18907 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
18910 Set_Has_Predicates (Full_T);
18912 end Process_Full_View;
18914 -----------------------------------
18915 -- Process_Incomplete_Dependents --
18916 -----------------------------------
18918 procedure Process_Incomplete_Dependents
18920 Full_T : Entity_Id;
18923 Inc_Elmt : Elmt_Id;
18924 Priv_Dep : Entity_Id;
18925 New_Subt : Entity_Id;
18927 Disc_Constraint : Elist_Id;
18930 if No (Private_Dependents (Inc_T)) then
18934 -- Itypes that may be generated by the completion of an incomplete
18935 -- subtype are not used by the back-end and not attached to the tree.
18936 -- They are created only for constraint-checking purposes.
18938 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
18939 while Present (Inc_Elmt) loop
18940 Priv_Dep := Node (Inc_Elmt);
18942 if Ekind (Priv_Dep) = E_Subprogram_Type then
18944 -- An Access_To_Subprogram type may have a return type or a
18945 -- parameter type that is incomplete. Replace with the full view.
18947 if Etype (Priv_Dep) = Inc_T then
18948 Set_Etype (Priv_Dep, Full_T);
18952 Formal : Entity_Id;
18955 Formal := First_Formal (Priv_Dep);
18956 while Present (Formal) loop
18957 if Etype (Formal) = Inc_T then
18958 Set_Etype (Formal, Full_T);
18961 Next_Formal (Formal);
18965 elsif Is_Overloadable (Priv_Dep) then
18967 -- If a subprogram in the incomplete dependents list is primitive
18968 -- for a tagged full type then mark it as a dispatching operation,
18969 -- check whether it overrides an inherited subprogram, and check
18970 -- restrictions on its controlling formals. Note that a protected
18971 -- operation is never dispatching: only its wrapper operation
18972 -- (which has convention Ada) is.
18974 if Is_Tagged_Type (Full_T)
18975 and then Is_Primitive (Priv_Dep)
18976 and then Convention (Priv_Dep) /= Convention_Protected
18978 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
18979 Set_Is_Dispatching_Operation (Priv_Dep);
18980 Check_Controlling_Formals (Full_T, Priv_Dep);
18983 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18985 -- Can happen during processing of a body before the completion
18986 -- of a TA type. Ignore, because spec is also on dependent list.
18990 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18991 -- corresponding subtype of the full view.
18993 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18994 Set_Subtype_Indication
18995 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
18996 Set_Etype (Priv_Dep, Full_T);
18997 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18998 Set_Analyzed (Parent (Priv_Dep), False);
19000 -- Reanalyze the declaration, suppressing the call to
19001 -- Enter_Name to avoid duplicate names.
19003 Analyze_Subtype_Declaration
19004 (N => Parent (Priv_Dep),
19007 -- Dependent is a subtype
19010 -- We build a new subtype indication using the full view of the
19011 -- incomplete parent. The discriminant constraints have been
19012 -- elaborated already at the point of the subtype declaration.
19014 New_Subt := Create_Itype (E_Void, N);
19016 if Has_Discriminants (Full_T) then
19017 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
19019 Disc_Constraint := No_Elist;
19022 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
19023 Set_Full_View (Priv_Dep, New_Subt);
19026 Next_Elmt (Inc_Elmt);
19028 end Process_Incomplete_Dependents;
19030 --------------------------------
19031 -- Process_Range_Expr_In_Decl --
19032 --------------------------------
19034 procedure Process_Range_Expr_In_Decl
19037 Subtyp : Entity_Id := Empty;
19038 Check_List : List_Id := Empty_List;
19039 R_Check_Off : Boolean := False;
19040 In_Iter_Schm : Boolean := False)
19043 R_Checks : Check_Result;
19044 Insert_Node : Node_Id;
19045 Def_Id : Entity_Id;
19048 Analyze_And_Resolve (R, Base_Type (T));
19050 if Nkind (R) = N_Range then
19052 -- In SPARK, all ranges should be static, with the exception of the
19053 -- discrete type definition of a loop parameter specification.
19055 if not In_Iter_Schm
19056 and then not Is_OK_Static_Range (R)
19058 Check_SPARK_Restriction ("range should be static", R);
19061 Lo := Low_Bound (R);
19062 Hi := High_Bound (R);
19064 -- We need to ensure validity of the bounds here, because if we
19065 -- go ahead and do the expansion, then the expanded code will get
19066 -- analyzed with range checks suppressed and we miss the check.
19067 -- Validity checks on the range of a quantified expression are
19068 -- delayed until the construct is transformed into a loop.
19070 if Nkind (Parent (R)) /= N_Loop_Parameter_Specification
19071 or else Nkind (Parent (Parent (R))) /= N_Quantified_Expression
19073 Validity_Check_Range (R);
19076 -- If there were errors in the declaration, try and patch up some
19077 -- common mistakes in the bounds. The cases handled are literals
19078 -- which are Integer where the expected type is Real and vice versa.
19079 -- These corrections allow the compilation process to proceed further
19080 -- along since some basic assumptions of the format of the bounds
19083 if Etype (R) = Any_Type then
19084 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
19086 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
19088 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
19090 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
19092 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
19094 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
19096 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
19098 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
19105 -- If the bounds of the range have been mistakenly given as string
19106 -- literals (perhaps in place of character literals), then an error
19107 -- has already been reported, but we rewrite the string literal as a
19108 -- bound of the range's type to avoid blowups in later processing
19109 -- that looks at static values.
19111 if Nkind (Lo) = N_String_Literal then
19113 Make_Attribute_Reference (Sloc (Lo),
19114 Attribute_Name => Name_First,
19115 Prefix => New_Occurrence_Of (T, Sloc (Lo))));
19116 Analyze_And_Resolve (Lo);
19119 if Nkind (Hi) = N_String_Literal then
19121 Make_Attribute_Reference (Sloc (Hi),
19122 Attribute_Name => Name_First,
19123 Prefix => New_Occurrence_Of (T, Sloc (Hi))));
19124 Analyze_And_Resolve (Hi);
19127 -- If bounds aren't scalar at this point then exit, avoiding
19128 -- problems with further processing of the range in this procedure.
19130 if not Is_Scalar_Type (Etype (Lo)) then
19134 -- Resolve (actually Sem_Eval) has checked that the bounds are in
19135 -- then range of the base type. Here we check whether the bounds
19136 -- are in the range of the subtype itself. Note that if the bounds
19137 -- represent the null range the Constraint_Error exception should
19140 -- ??? The following code should be cleaned up as follows
19142 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
19143 -- is done in the call to Range_Check (R, T); below
19145 -- 2. The use of R_Check_Off should be investigated and possibly
19146 -- removed, this would clean up things a bit.
19148 if Is_Null_Range (Lo, Hi) then
19152 -- Capture values of bounds and generate temporaries for them
19153 -- if needed, before applying checks, since checks may cause
19154 -- duplication of the expression without forcing evaluation.
19156 -- The forced evaluation removes side effects from expressions,
19157 -- which should occur also in GNATprove mode. Otherwise, we end up
19158 -- with unexpected insertions of actions at places where this is
19159 -- not supposed to occur, e.g. on default parameters of a call.
19161 if Expander_Active or GNATprove_Mode then
19163 -- If no subtype name, then just call Force_Evaluation to
19164 -- create declarations as needed to deal with side effects.
19165 -- Also ignore calls from within a record type, where we
19166 -- have possible scoping issues.
19168 if No (Subtyp) or else Is_Record_Type (Current_Scope) then
19169 Force_Evaluation (Lo);
19170 Force_Evaluation (Hi);
19172 -- If a subtype is given, then we capture the bounds if they
19173 -- are not known at compile time, using constant identifiers
19174 -- xxx_FIRST and xxx_LAST where xxx is the name of the subtype.
19176 -- Note: we do this transformation even if expansion is not
19177 -- active, and in particular we do it in GNATprove_Mode since
19178 -- the transformation is in general required to ensure that the
19179 -- resulting tree has proper Ada semantics.
19181 -- Historical note: We used to just do Force_Evaluation calls
19182 -- in all cases, but it is better to capture the bounds with
19183 -- proper non-serialized names, since these will be accessed
19184 -- from other units, and hence may be public, and also we can
19185 -- then expand 'First and 'Last references to be references to
19186 -- these special names.
19189 if not Compile_Time_Known_Value (Lo)
19191 -- No need to capture bounds if they already are
19192 -- references to constants.
19194 and then not (Is_Entity_Name (Lo)
19195 and then Is_Constant_Object (Entity (Lo)))
19198 Loc : constant Source_Ptr := Sloc (Lo);
19199 Lov : constant Entity_Id :=
19200 Make_Defining_Identifier (Loc,
19202 New_External_Name (Chars (Subtyp), "_FIRST"));
19205 Make_Object_Declaration (Loc,
19206 Defining_Identifier => Lov,
19207 Object_Definition =>
19208 New_Occurrence_Of (Base_Type (T), Loc),
19209 Constant_Present => True,
19210 Expression => Relocate_Node (Lo)));
19211 Rewrite (Lo, New_Occurrence_Of (Lov, Loc));
19215 if not Compile_Time_Known_Value (Hi)
19216 and then not (Is_Entity_Name (Hi)
19217 and then Is_Constant_Object (Entity (Hi)))
19220 Loc : constant Source_Ptr := Sloc (Hi);
19221 Hiv : constant Entity_Id :=
19222 Make_Defining_Identifier (Loc,
19224 New_External_Name (Chars (Subtyp), "_LAST"));
19227 Make_Object_Declaration (Loc,
19228 Defining_Identifier => Hiv,
19229 Object_Definition =>
19230 New_Occurrence_Of (Base_Type (T), Loc),
19231 Constant_Present => True,
19232 Expression => Relocate_Node (Hi)));
19233 Rewrite (Hi, New_Occurrence_Of (Hiv, Loc));
19239 -- We use a flag here instead of suppressing checks on the
19240 -- type because the type we check against isn't necessarily
19241 -- the place where we put the check.
19243 if not R_Check_Off then
19244 R_Checks := Get_Range_Checks (R, T);
19246 -- Look up tree to find an appropriate insertion point. We
19247 -- can't just use insert_actions because later processing
19248 -- depends on the insertion node. Prior to Ada 2012 the
19249 -- insertion point could only be a declaration or a loop, but
19250 -- quantified expressions can appear within any context in an
19251 -- expression, and the insertion point can be any statement,
19252 -- pragma, or declaration.
19254 Insert_Node := Parent (R);
19255 while Present (Insert_Node) loop
19257 Nkind (Insert_Node) in N_Declaration
19260 (Insert_Node, N_Component_Declaration,
19261 N_Loop_Parameter_Specification,
19262 N_Function_Specification,
19263 N_Procedure_Specification);
19265 exit when Nkind (Insert_Node) in N_Later_Decl_Item
19266 or else Nkind (Insert_Node) in
19267 N_Statement_Other_Than_Procedure_Call
19268 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
19271 Insert_Node := Parent (Insert_Node);
19274 -- Why would Type_Decl not be present??? Without this test,
19275 -- short regression tests fail.
19277 if Present (Insert_Node) then
19279 -- Case of loop statement. Verify that the range is part
19280 -- of the subtype indication of the iteration scheme.
19282 if Nkind (Insert_Node) = N_Loop_Statement then
19287 Indic := Parent (R);
19288 while Present (Indic)
19289 and then Nkind (Indic) /= N_Subtype_Indication
19291 Indic := Parent (Indic);
19294 if Present (Indic) then
19295 Def_Id := Etype (Subtype_Mark (Indic));
19297 Insert_Range_Checks
19301 Sloc (Insert_Node),
19303 Do_Before => True);
19307 -- Insertion before a declaration. If the declaration
19308 -- includes discriminants, the list of applicable checks
19309 -- is given by the caller.
19311 elsif Nkind (Insert_Node) in N_Declaration then
19312 Def_Id := Defining_Identifier (Insert_Node);
19314 if (Ekind (Def_Id) = E_Record_Type
19315 and then Depends_On_Discriminant (R))
19317 (Ekind (Def_Id) = E_Protected_Type
19318 and then Has_Discriminants (Def_Id))
19320 Append_Range_Checks
19322 Check_List, Def_Id, Sloc (Insert_Node), R);
19325 Insert_Range_Checks
19327 Insert_Node, Def_Id, Sloc (Insert_Node), R);
19331 -- Insertion before a statement. Range appears in the
19332 -- context of a quantified expression. Insertion will
19333 -- take place when expression is expanded.
19342 -- Case of other than an explicit N_Range node
19344 -- The forced evaluation removes side effects from expressions, which
19345 -- should occur also in GNATprove mode. Otherwise, we end up with
19346 -- unexpected insertions of actions at places where this is not
19347 -- supposed to occur, e.g. on default parameters of a call.
19349 elsif Expander_Active or GNATprove_Mode then
19350 Get_Index_Bounds (R, Lo, Hi);
19351 Force_Evaluation (Lo);
19352 Force_Evaluation (Hi);
19354 end Process_Range_Expr_In_Decl;
19356 --------------------------------------
19357 -- Process_Real_Range_Specification --
19358 --------------------------------------
19360 procedure Process_Real_Range_Specification (Def : Node_Id) is
19361 Spec : constant Node_Id := Real_Range_Specification (Def);
19364 Err : Boolean := False;
19366 procedure Analyze_Bound (N : Node_Id);
19367 -- Analyze and check one bound
19369 -------------------
19370 -- Analyze_Bound --
19371 -------------------
19373 procedure Analyze_Bound (N : Node_Id) is
19375 Analyze_And_Resolve (N, Any_Real);
19377 if not Is_OK_Static_Expression (N) then
19378 Flag_Non_Static_Expr
19379 ("bound in real type definition is not static!", N);
19384 -- Start of processing for Process_Real_Range_Specification
19387 if Present (Spec) then
19388 Lo := Low_Bound (Spec);
19389 Hi := High_Bound (Spec);
19390 Analyze_Bound (Lo);
19391 Analyze_Bound (Hi);
19393 -- If error, clear away junk range specification
19396 Set_Real_Range_Specification (Def, Empty);
19399 end Process_Real_Range_Specification;
19401 ---------------------
19402 -- Process_Subtype --
19403 ---------------------
19405 function Process_Subtype
19407 Related_Nod : Node_Id;
19408 Related_Id : Entity_Id := Empty;
19409 Suffix : Character := ' ') return Entity_Id
19412 Def_Id : Entity_Id;
19413 Error_Node : Node_Id;
19414 Full_View_Id : Entity_Id;
19415 Subtype_Mark_Id : Entity_Id;
19417 May_Have_Null_Exclusion : Boolean;
19419 procedure Check_Incomplete (T : Entity_Id);
19420 -- Called to verify that an incomplete type is not used prematurely
19422 ----------------------
19423 -- Check_Incomplete --
19424 ----------------------
19426 procedure Check_Incomplete (T : Entity_Id) is
19428 -- Ada 2005 (AI-412): Incomplete subtypes are legal
19430 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
19432 not (Ada_Version >= Ada_2005
19434 (Nkind (Parent (T)) = N_Subtype_Declaration
19436 (Nkind (Parent (T)) = N_Subtype_Indication
19437 and then Nkind (Parent (Parent (T))) =
19438 N_Subtype_Declaration)))
19440 Error_Msg_N ("invalid use of type before its full declaration", T);
19442 end Check_Incomplete;
19444 -- Start of processing for Process_Subtype
19447 -- Case of no constraints present
19449 if Nkind (S) /= N_Subtype_Indication then
19451 Check_Incomplete (S);
19454 -- Ada 2005 (AI-231): Static check
19456 if Ada_Version >= Ada_2005
19457 and then Present (P)
19458 and then Null_Exclusion_Present (P)
19459 and then Nkind (P) /= N_Access_To_Object_Definition
19460 and then not Is_Access_Type (Entity (S))
19462 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
19465 -- The following is ugly, can't we have a range or even a flag???
19467 May_Have_Null_Exclusion :=
19468 Nkind_In (P, N_Access_Definition,
19469 N_Access_Function_Definition,
19470 N_Access_Procedure_Definition,
19471 N_Access_To_Object_Definition,
19473 N_Component_Definition)
19475 Nkind_In (P, N_Derived_Type_Definition,
19476 N_Discriminant_Specification,
19477 N_Formal_Object_Declaration,
19478 N_Object_Declaration,
19479 N_Object_Renaming_Declaration,
19480 N_Parameter_Specification,
19481 N_Subtype_Declaration);
19483 -- Create an Itype that is a duplicate of Entity (S) but with the
19484 -- null-exclusion attribute.
19486 if May_Have_Null_Exclusion
19487 and then Is_Access_Type (Entity (S))
19488 and then Null_Exclusion_Present (P)
19490 -- No need to check the case of an access to object definition.
19491 -- It is correct to define double not-null pointers.
19494 -- type Not_Null_Int_Ptr is not null access Integer;
19495 -- type Acc is not null access Not_Null_Int_Ptr;
19497 and then Nkind (P) /= N_Access_To_Object_Definition
19499 if Can_Never_Be_Null (Entity (S)) then
19500 case Nkind (Related_Nod) is
19501 when N_Full_Type_Declaration =>
19502 if Nkind (Type_Definition (Related_Nod))
19503 in N_Array_Type_Definition
19507 (Component_Definition
19508 (Type_Definition (Related_Nod)));
19511 Subtype_Indication (Type_Definition (Related_Nod));
19514 when N_Subtype_Declaration =>
19515 Error_Node := Subtype_Indication (Related_Nod);
19517 when N_Object_Declaration =>
19518 Error_Node := Object_Definition (Related_Nod);
19520 when N_Component_Declaration =>
19522 Subtype_Indication (Component_Definition (Related_Nod));
19524 when N_Allocator =>
19525 Error_Node := Expression (Related_Nod);
19528 pragma Assert (False);
19529 Error_Node := Related_Nod;
19533 ("`NOT NULL` not allowed (& already excludes null)",
19539 Create_Null_Excluding_Itype
19541 Related_Nod => P));
19542 Set_Entity (S, Etype (S));
19547 -- Case of constraint present, so that we have an N_Subtype_Indication
19548 -- node (this node is created only if constraints are present).
19551 Find_Type (Subtype_Mark (S));
19553 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
19555 (Nkind (Parent (S)) = N_Subtype_Declaration
19556 and then Is_Itype (Defining_Identifier (Parent (S))))
19558 Check_Incomplete (Subtype_Mark (S));
19562 Subtype_Mark_Id := Entity (Subtype_Mark (S));
19564 -- Explicit subtype declaration case
19566 if Nkind (P) = N_Subtype_Declaration then
19567 Def_Id := Defining_Identifier (P);
19569 -- Explicit derived type definition case
19571 elsif Nkind (P) = N_Derived_Type_Definition then
19572 Def_Id := Defining_Identifier (Parent (P));
19574 -- Implicit case, the Def_Id must be created as an implicit type.
19575 -- The one exception arises in the case of concurrent types, array
19576 -- and access types, where other subsidiary implicit types may be
19577 -- created and must appear before the main implicit type. In these
19578 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
19579 -- has not yet been called to create Def_Id.
19582 if Is_Array_Type (Subtype_Mark_Id)
19583 or else Is_Concurrent_Type (Subtype_Mark_Id)
19584 or else Is_Access_Type (Subtype_Mark_Id)
19588 -- For the other cases, we create a new unattached Itype,
19589 -- and set the indication to ensure it gets attached later.
19593 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19597 -- If the kind of constraint is invalid for this kind of type,
19598 -- then give an error, and then pretend no constraint was given.
19600 if not Is_Valid_Constraint_Kind
19601 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
19604 ("incorrect constraint for this kind of type", Constraint (S));
19606 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
19608 -- Set Ekind of orphan itype, to prevent cascaded errors
19610 if Present (Def_Id) then
19611 Set_Ekind (Def_Id, Ekind (Any_Type));
19614 -- Make recursive call, having got rid of the bogus constraint
19616 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
19619 -- Remaining processing depends on type. Select on Base_Type kind to
19620 -- ensure getting to the concrete type kind in the case of a private
19621 -- subtype (needed when only doing semantic analysis).
19623 case Ekind (Base_Type (Subtype_Mark_Id)) is
19624 when Access_Kind =>
19626 -- If this is a constraint on a class-wide type, discard it.
19627 -- There is currently no way to express a partial discriminant
19628 -- constraint on a type with unknown discriminants. This is
19629 -- a pathology that the ACATS wisely decides not to test.
19631 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
19632 if Comes_From_Source (S) then
19634 ("constraint on class-wide type ignored??",
19638 if Nkind (P) = N_Subtype_Declaration then
19639 Set_Subtype_Indication (P,
19640 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
19643 return Subtype_Mark_Id;
19646 Constrain_Access (Def_Id, S, Related_Nod);
19649 and then Is_Itype (Designated_Type (Def_Id))
19650 and then Nkind (Related_Nod) = N_Subtype_Declaration
19651 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
19653 Build_Itype_Reference
19654 (Designated_Type (Def_Id), Related_Nod);
19658 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
19660 when Decimal_Fixed_Point_Kind =>
19661 Constrain_Decimal (Def_Id, S);
19663 when Enumeration_Kind =>
19664 Constrain_Enumeration (Def_Id, S);
19666 when Ordinary_Fixed_Point_Kind =>
19667 Constrain_Ordinary_Fixed (Def_Id, S);
19670 Constrain_Float (Def_Id, S);
19672 when Integer_Kind =>
19673 Constrain_Integer (Def_Id, S);
19675 when E_Record_Type |
19678 E_Incomplete_Type =>
19679 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19681 if Ekind (Def_Id) = E_Incomplete_Type then
19682 Set_Private_Dependents (Def_Id, New_Elmt_List);
19685 when Private_Kind =>
19686 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19687 Set_Private_Dependents (Def_Id, New_Elmt_List);
19689 -- In case of an invalid constraint prevent further processing
19690 -- since the type constructed is missing expected fields.
19692 if Etype (Def_Id) = Any_Type then
19696 -- If the full view is that of a task with discriminants,
19697 -- we must constrain both the concurrent type and its
19698 -- corresponding record type. Otherwise we will just propagate
19699 -- the constraint to the full view, if available.
19701 if Present (Full_View (Subtype_Mark_Id))
19702 and then Has_Discriminants (Subtype_Mark_Id)
19703 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
19706 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19708 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
19709 Constrain_Concurrent (Full_View_Id, S,
19710 Related_Nod, Related_Id, Suffix);
19711 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
19712 Set_Full_View (Def_Id, Full_View_Id);
19714 -- Introduce an explicit reference to the private subtype,
19715 -- to prevent scope anomalies in gigi if first use appears
19716 -- in a nested context, e.g. a later function body.
19717 -- Should this be generated in other contexts than a full
19718 -- type declaration?
19720 if Is_Itype (Def_Id)
19722 Nkind (Parent (P)) = N_Full_Type_Declaration
19724 Build_Itype_Reference (Def_Id, Parent (P));
19728 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
19731 when Concurrent_Kind =>
19732 Constrain_Concurrent (Def_Id, S,
19733 Related_Nod, Related_Id, Suffix);
19736 Error_Msg_N ("invalid subtype mark in subtype indication", S);
19739 -- Size and Convention are always inherited from the base type
19741 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
19742 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
19746 end Process_Subtype;
19748 ---------------------------------------
19749 -- Check_Anonymous_Access_Components --
19750 ---------------------------------------
19752 procedure Check_Anonymous_Access_Components
19753 (Typ_Decl : Node_Id;
19756 Comp_List : Node_Id)
19758 Loc : constant Source_Ptr := Sloc (Typ_Decl);
19759 Anon_Access : Entity_Id;
19762 Comp_Def : Node_Id;
19764 Type_Def : Node_Id;
19766 procedure Build_Incomplete_Type_Declaration;
19767 -- If the record type contains components that include an access to the
19768 -- current record, then create an incomplete type declaration for the
19769 -- record, to be used as the designated type of the anonymous access.
19770 -- This is done only once, and only if there is no previous partial
19771 -- view of the type.
19773 function Designates_T (Subt : Node_Id) return Boolean;
19774 -- Check whether a node designates the enclosing record type, or 'Class
19777 function Mentions_T (Acc_Def : Node_Id) return Boolean;
19778 -- Check whether an access definition includes a reference to
19779 -- the enclosing record type. The reference can be a subtype mark
19780 -- in the access definition itself, a 'Class attribute reference, or
19781 -- recursively a reference appearing in a parameter specification
19782 -- or result definition of an access_to_subprogram definition.
19784 --------------------------------------
19785 -- Build_Incomplete_Type_Declaration --
19786 --------------------------------------
19788 procedure Build_Incomplete_Type_Declaration is
19793 -- Is_Tagged indicates whether the type is tagged. It is tagged if
19794 -- it's "is new ... with record" or else "is tagged record ...".
19796 Is_Tagged : constant Boolean :=
19797 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
19800 (Record_Extension_Part (Type_Definition (Typ_Decl))))
19802 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
19803 and then Tagged_Present (Type_Definition (Typ_Decl)));
19806 -- If there is a previous partial view, no need to create a new one
19807 -- If the partial view, given by Prev, is incomplete, If Prev is
19808 -- a private declaration, full declaration is flagged accordingly.
19810 if Prev /= Typ then
19812 Make_Class_Wide_Type (Prev);
19813 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
19814 Set_Etype (Class_Wide_Type (Typ), Typ);
19819 elsif Has_Private_Declaration (Typ) then
19821 -- If we refer to T'Class inside T, and T is the completion of a
19822 -- private type, then we need to make sure the class-wide type
19826 Make_Class_Wide_Type (Typ);
19831 -- If there was a previous anonymous access type, the incomplete
19832 -- type declaration will have been created already.
19834 elsif Present (Current_Entity (Typ))
19835 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
19836 and then Full_View (Current_Entity (Typ)) = Typ
19839 and then Comes_From_Source (Current_Entity (Typ))
19840 and then not Is_Tagged_Type (Current_Entity (Typ))
19842 Make_Class_Wide_Type (Typ);
19844 ("incomplete view of tagged type should be declared tagged??",
19845 Parent (Current_Entity (Typ)));
19850 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
19851 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
19853 -- Type has already been inserted into the current scope. Remove
19854 -- it, and add incomplete declaration for type, so that subsequent
19855 -- anonymous access types can use it. The entity is unchained from
19856 -- the homonym list and from immediate visibility. After analysis,
19857 -- the entity in the incomplete declaration becomes immediately
19858 -- visible in the record declaration that follows.
19860 H := Current_Entity (Typ);
19863 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
19866 and then Homonym (H) /= Typ
19868 H := Homonym (Typ);
19871 Set_Homonym (H, Homonym (Typ));
19874 Insert_Before (Typ_Decl, Decl);
19876 Set_Full_View (Inc_T, Typ);
19880 -- Create a common class-wide type for both views, and set the
19881 -- Etype of the class-wide type to the full view.
19883 Make_Class_Wide_Type (Inc_T);
19884 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
19885 Set_Etype (Class_Wide_Type (Typ), Typ);
19888 end Build_Incomplete_Type_Declaration;
19894 function Designates_T (Subt : Node_Id) return Boolean is
19895 Type_Id : constant Name_Id := Chars (Typ);
19897 function Names_T (Nam : Node_Id) return Boolean;
19898 -- The record type has not been introduced in the current scope
19899 -- yet, so we must examine the name of the type itself, either
19900 -- an identifier T, or an expanded name of the form P.T, where
19901 -- P denotes the current scope.
19907 function Names_T (Nam : Node_Id) return Boolean is
19909 if Nkind (Nam) = N_Identifier then
19910 return Chars (Nam) = Type_Id;
19912 elsif Nkind (Nam) = N_Selected_Component then
19913 if Chars (Selector_Name (Nam)) = Type_Id then
19914 if Nkind (Prefix (Nam)) = N_Identifier then
19915 return Chars (Prefix (Nam)) = Chars (Current_Scope);
19917 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
19918 return Chars (Selector_Name (Prefix (Nam))) =
19919 Chars (Current_Scope);
19933 -- Start of processing for Designates_T
19936 if Nkind (Subt) = N_Identifier then
19937 return Chars (Subt) = Type_Id;
19939 -- Reference can be through an expanded name which has not been
19940 -- analyzed yet, and which designates enclosing scopes.
19942 elsif Nkind (Subt) = N_Selected_Component then
19943 if Names_T (Subt) then
19946 -- Otherwise it must denote an entity that is already visible.
19947 -- The access definition may name a subtype of the enclosing
19948 -- type, if there is a previous incomplete declaration for it.
19951 Find_Selected_Component (Subt);
19953 Is_Entity_Name (Subt)
19954 and then Scope (Entity (Subt)) = Current_Scope
19956 (Chars (Base_Type (Entity (Subt))) = Type_Id
19958 (Is_Class_Wide_Type (Entity (Subt))
19960 Chars (Etype (Base_Type (Entity (Subt)))) =
19964 -- A reference to the current type may appear as the prefix of
19965 -- a 'Class attribute.
19967 elsif Nkind (Subt) = N_Attribute_Reference
19968 and then Attribute_Name (Subt) = Name_Class
19970 return Names_T (Prefix (Subt));
19981 function Mentions_T (Acc_Def : Node_Id) return Boolean is
19982 Param_Spec : Node_Id;
19984 Acc_Subprg : constant Node_Id :=
19985 Access_To_Subprogram_Definition (Acc_Def);
19988 if No (Acc_Subprg) then
19989 return Designates_T (Subtype_Mark (Acc_Def));
19992 -- Component is an access_to_subprogram: examine its formals,
19993 -- and result definition in the case of an access_to_function.
19995 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
19996 while Present (Param_Spec) loop
19997 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
19998 and then Mentions_T (Parameter_Type (Param_Spec))
20002 elsif Designates_T (Parameter_Type (Param_Spec)) then
20009 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
20010 if Nkind (Result_Definition (Acc_Subprg)) =
20011 N_Access_Definition
20013 return Mentions_T (Result_Definition (Acc_Subprg));
20015 return Designates_T (Result_Definition (Acc_Subprg));
20022 -- Start of processing for Check_Anonymous_Access_Components
20025 if No (Comp_List) then
20029 Comp := First (Component_Items (Comp_List));
20030 while Present (Comp) loop
20031 if Nkind (Comp) = N_Component_Declaration
20033 (Access_Definition (Component_Definition (Comp)))
20035 Mentions_T (Access_Definition (Component_Definition (Comp)))
20037 Comp_Def := Component_Definition (Comp);
20039 Access_To_Subprogram_Definition
20040 (Access_Definition (Comp_Def));
20042 Build_Incomplete_Type_Declaration;
20043 Anon_Access := Make_Temporary (Loc, 'S');
20045 -- Create a declaration for the anonymous access type: either
20046 -- an access_to_object or an access_to_subprogram.
20048 if Present (Acc_Def) then
20049 if Nkind (Acc_Def) = N_Access_Function_Definition then
20051 Make_Access_Function_Definition (Loc,
20052 Parameter_Specifications =>
20053 Parameter_Specifications (Acc_Def),
20054 Result_Definition => Result_Definition (Acc_Def));
20057 Make_Access_Procedure_Definition (Loc,
20058 Parameter_Specifications =>
20059 Parameter_Specifications (Acc_Def));
20064 Make_Access_To_Object_Definition (Loc,
20065 Subtype_Indication =>
20068 (Access_Definition (Comp_Def))));
20070 Set_Constant_Present
20071 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
20073 (Type_Def, All_Present (Access_Definition (Comp_Def)));
20076 Set_Null_Exclusion_Present
20078 Null_Exclusion_Present (Access_Definition (Comp_Def)));
20081 Make_Full_Type_Declaration (Loc,
20082 Defining_Identifier => Anon_Access,
20083 Type_Definition => Type_Def);
20085 Insert_Before (Typ_Decl, Decl);
20088 -- If an access to subprogram, create the extra formals
20090 if Present (Acc_Def) then
20091 Create_Extra_Formals (Designated_Type (Anon_Access));
20093 -- If an access to object, preserve entity of designated type,
20094 -- for ASIS use, before rewriting the component definition.
20101 Desig := Entity (Subtype_Indication (Type_Def));
20103 -- If the access definition is to the current record,
20104 -- the visible entity at this point is an incomplete
20105 -- type. Retrieve the full view to simplify ASIS queries
20107 if Ekind (Desig) = E_Incomplete_Type then
20108 Desig := Full_View (Desig);
20112 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
20117 Make_Component_Definition (Loc,
20118 Subtype_Indication =>
20119 New_Occurrence_Of (Anon_Access, Loc)));
20121 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
20122 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
20124 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
20127 Set_Is_Local_Anonymous_Access (Anon_Access);
20133 if Present (Variant_Part (Comp_List)) then
20137 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
20138 while Present (V) loop
20139 Check_Anonymous_Access_Components
20140 (Typ_Decl, Typ, Prev, Component_List (V));
20141 Next_Non_Pragma (V);
20145 end Check_Anonymous_Access_Components;
20147 ----------------------------------
20148 -- Preanalyze_Assert_Expression --
20149 ----------------------------------
20151 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
20153 In_Assertion_Expr := In_Assertion_Expr + 1;
20154 Preanalyze_Spec_Expression (N, T);
20155 In_Assertion_Expr := In_Assertion_Expr - 1;
20156 end Preanalyze_Assert_Expression;
20158 --------------------------------
20159 -- Preanalyze_Spec_Expression --
20160 --------------------------------
20162 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
20163 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
20165 In_Spec_Expression := True;
20166 Preanalyze_And_Resolve (N, T);
20167 In_Spec_Expression := Save_In_Spec_Expression;
20168 end Preanalyze_Spec_Expression;
20170 -----------------------------
20171 -- Record_Type_Declaration --
20172 -----------------------------
20174 procedure Record_Type_Declaration
20179 Def : constant Node_Id := Type_Definition (N);
20180 Is_Tagged : Boolean;
20181 Tag_Comp : Entity_Id;
20184 -- These flags must be initialized before calling Process_Discriminants
20185 -- because this routine makes use of them.
20187 Set_Ekind (T, E_Record_Type);
20189 Init_Size_Align (T);
20190 Set_Interfaces (T, No_Elist);
20191 Set_Stored_Constraint (T, No_Elist);
20192 Set_Default_SSO (T);
20196 if Ada_Version < Ada_2005
20197 or else not Interface_Present (Def)
20199 if Limited_Present (Def) then
20200 Check_SPARK_Restriction ("limited is not allowed", N);
20203 if Abstract_Present (Def) then
20204 Check_SPARK_Restriction ("abstract is not allowed", N);
20207 -- The flag Is_Tagged_Type might have already been set by
20208 -- Find_Type_Name if it detected an error for declaration T. This
20209 -- arises in the case of private tagged types where the full view
20210 -- omits the word tagged.
20213 Tagged_Present (Def)
20214 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20216 Set_Is_Tagged_Type (T, Is_Tagged);
20217 Set_Is_Limited_Record (T, Limited_Present (Def));
20219 -- Type is abstract if full declaration carries keyword, or if
20220 -- previous partial view did.
20222 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20223 or else Abstract_Present (Def));
20226 Check_SPARK_Restriction ("interface is not allowed", N);
20229 Analyze_Interface_Declaration (T, Def);
20231 if Present (Discriminant_Specifications (N)) then
20233 ("interface types cannot have discriminants",
20234 Defining_Identifier
20235 (First (Discriminant_Specifications (N))));
20239 -- First pass: if there are self-referential access components,
20240 -- create the required anonymous access type declarations, and if
20241 -- need be an incomplete type declaration for T itself.
20243 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20245 if Ada_Version >= Ada_2005
20246 and then Present (Interface_List (Def))
20248 Check_Interfaces (N, Def);
20251 Ifaces_List : Elist_Id;
20254 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20255 -- already in the parents.
20259 Ifaces_List => Ifaces_List,
20260 Exclude_Parents => True);
20262 Set_Interfaces (T, Ifaces_List);
20266 -- Records constitute a scope for the component declarations within.
20267 -- The scope is created prior to the processing of these declarations.
20268 -- Discriminants are processed first, so that they are visible when
20269 -- processing the other components. The Ekind of the record type itself
20270 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20272 -- Enter record scope
20276 -- If an incomplete or private type declaration was already given for
20277 -- the type, then this scope already exists, and the discriminants have
20278 -- been declared within. We must verify that the full declaration
20279 -- matches the incomplete one.
20281 Check_Or_Process_Discriminants (N, T, Prev);
20283 Set_Is_Constrained (T, not Has_Discriminants (T));
20284 Set_Has_Delayed_Freeze (T, True);
20286 -- For tagged types add a manually analyzed component corresponding
20287 -- to the component _tag, the corresponding piece of tree will be
20288 -- expanded as part of the freezing actions if it is not a CPP_Class.
20292 -- Do not add the tag unless we are in expansion mode
20294 if Expander_Active then
20295 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20296 Enter_Name (Tag_Comp);
20298 Set_Ekind (Tag_Comp, E_Component);
20299 Set_Is_Tag (Tag_Comp);
20300 Set_Is_Aliased (Tag_Comp);
20301 Set_Etype (Tag_Comp, RTE (RE_Tag));
20302 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20303 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20304 Init_Component_Location (Tag_Comp);
20306 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20307 -- implemented interfaces.
20309 if Has_Interfaces (T) then
20310 Add_Interface_Tag_Components (N, T);
20314 Make_Class_Wide_Type (T);
20315 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20318 -- We must suppress range checks when processing record components in
20319 -- the presence of discriminants, since we don't want spurious checks to
20320 -- be generated during their analysis, but Suppress_Range_Checks flags
20321 -- must be reset the after processing the record definition.
20323 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20324 -- couldn't we just use the normal range check suppression method here.
20325 -- That would seem cleaner ???
20327 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20328 Set_Kill_Range_Checks (T, True);
20329 Record_Type_Definition (Def, Prev);
20330 Set_Kill_Range_Checks (T, False);
20332 Record_Type_Definition (Def, Prev);
20335 -- Exit from record scope
20339 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20340 -- the implemented interfaces and associate them an aliased entity.
20343 and then not Is_Empty_List (Interface_List (Def))
20345 Derive_Progenitor_Subprograms (T, T);
20348 Check_Function_Writable_Actuals (N);
20349 end Record_Type_Declaration;
20351 ----------------------------
20352 -- Record_Type_Definition --
20353 ----------------------------
20355 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20356 Component : Entity_Id;
20357 Ctrl_Components : Boolean := False;
20358 Final_Storage_Only : Boolean;
20362 if Ekind (Prev_T) = E_Incomplete_Type then
20363 T := Full_View (Prev_T);
20368 -- In SPARK, tagged types and type extensions may only be declared in
20369 -- the specification of library unit packages.
20371 if Present (Def) and then Is_Tagged_Type (T) then
20377 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
20378 Typ := Parent (Def);
20381 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
20382 Typ := Parent (Parent (Def));
20385 Ctxt := Parent (Typ);
20387 if Nkind (Ctxt) = N_Package_Body
20388 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
20390 Check_SPARK_Restriction
20391 ("type should be defined in package specification", Typ);
20393 elsif Nkind (Ctxt) /= N_Package_Specification
20394 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
20396 Check_SPARK_Restriction
20397 ("type should be defined in library unit package", Typ);
20402 Final_Storage_Only := not Is_Controlled (T);
20404 -- Ada 2005: Check whether an explicit Limited is present in a derived
20405 -- type declaration.
20407 if Nkind (Parent (Def)) = N_Derived_Type_Definition
20408 and then Limited_Present (Parent (Def))
20410 Set_Is_Limited_Record (T);
20413 -- If the component list of a record type is defined by the reserved
20414 -- word null and there is no discriminant part, then the record type has
20415 -- no components and all records of the type are null records (RM 3.7)
20416 -- This procedure is also called to process the extension part of a
20417 -- record extension, in which case the current scope may have inherited
20421 or else No (Component_List (Def))
20422 or else Null_Present (Component_List (Def))
20424 if not Is_Tagged_Type (T) then
20425 Check_SPARK_Restriction ("untagged record cannot be null", Def);
20429 Analyze_Declarations (Component_Items (Component_List (Def)));
20431 if Present (Variant_Part (Component_List (Def))) then
20432 Check_SPARK_Restriction ("variant part is not allowed", Def);
20433 Analyze (Variant_Part (Component_List (Def)));
20437 -- After completing the semantic analysis of the record definition,
20438 -- record components, both new and inherited, are accessible. Set their
20439 -- kind accordingly. Exclude malformed itypes from illegal declarations,
20440 -- whose Ekind may be void.
20442 Component := First_Entity (Current_Scope);
20443 while Present (Component) loop
20444 if Ekind (Component) = E_Void
20445 and then not Is_Itype (Component)
20447 Set_Ekind (Component, E_Component);
20448 Init_Component_Location (Component);
20451 if Has_Task (Etype (Component)) then
20455 if Has_Protected (Etype (Component)) then
20456 Set_Has_Protected (T);
20459 if Ekind (Component) /= E_Component then
20462 -- Do not set Has_Controlled_Component on a class-wide equivalent
20463 -- type. See Make_CW_Equivalent_Type.
20465 elsif not Is_Class_Wide_Equivalent_Type (T)
20466 and then (Has_Controlled_Component (Etype (Component))
20467 or else (Chars (Component) /= Name_uParent
20468 and then Is_Controlled (Etype (Component))))
20470 Set_Has_Controlled_Component (T, True);
20471 Final_Storage_Only :=
20473 and then Finalize_Storage_Only (Etype (Component));
20474 Ctrl_Components := True;
20477 Next_Entity (Component);
20480 -- A Type is Finalize_Storage_Only only if all its controlled components
20483 if Ctrl_Components then
20484 Set_Finalize_Storage_Only (T, Final_Storage_Only);
20487 -- Place reference to end record on the proper entity, which may
20488 -- be a partial view.
20490 if Present (Def) then
20491 Process_End_Label (Def, 'e', Prev_T);
20493 end Record_Type_Definition;
20495 ------------------------
20496 -- Replace_Components --
20497 ------------------------
20499 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
20500 function Process (N : Node_Id) return Traverse_Result;
20506 function Process (N : Node_Id) return Traverse_Result is
20510 if Nkind (N) = N_Discriminant_Specification then
20511 Comp := First_Discriminant (Typ);
20512 while Present (Comp) loop
20513 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20514 Set_Defining_Identifier (N, Comp);
20518 Next_Discriminant (Comp);
20521 elsif Nkind (N) = N_Component_Declaration then
20522 Comp := First_Component (Typ);
20523 while Present (Comp) loop
20524 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20525 Set_Defining_Identifier (N, Comp);
20529 Next_Component (Comp);
20536 procedure Replace is new Traverse_Proc (Process);
20538 -- Start of processing for Replace_Components
20542 end Replace_Components;
20544 -------------------------------
20545 -- Set_Completion_Referenced --
20546 -------------------------------
20548 procedure Set_Completion_Referenced (E : Entity_Id) is
20550 -- If in main unit, mark entity that is a completion as referenced,
20551 -- warnings go on the partial view when needed.
20553 if In_Extended_Main_Source_Unit (E) then
20554 Set_Referenced (E);
20556 end Set_Completion_Referenced;
20558 ---------------------
20559 -- Set_Default_SSO --
20560 ---------------------
20562 procedure Set_Default_SSO (T : Entity_Id) is
20564 case Opt.Default_SSO is
20568 Set_SSO_Set_Low_By_Default (T, True);
20570 Set_SSO_Set_High_By_Default (T, True);
20572 raise Program_Error;
20574 end Set_Default_SSO;
20576 ---------------------
20577 -- Set_Fixed_Range --
20578 ---------------------
20580 -- The range for fixed-point types is complicated by the fact that we
20581 -- do not know the exact end points at the time of the declaration. This
20582 -- is true for three reasons:
20584 -- A size clause may affect the fudging of the end-points.
20585 -- A small clause may affect the values of the end-points.
20586 -- We try to include the end-points if it does not affect the size.
20588 -- This means that the actual end-points must be established at the
20589 -- point when the type is frozen. Meanwhile, we first narrow the range
20590 -- as permitted (so that it will fit if necessary in a small specified
20591 -- size), and then build a range subtree with these narrowed bounds.
20592 -- Set_Fixed_Range constructs the range from real literal values, and
20593 -- sets the range as the Scalar_Range of the given fixed-point type entity.
20595 -- The parent of this range is set to point to the entity so that it is
20596 -- properly hooked into the tree (unlike normal Scalar_Range entries for
20597 -- other scalar types, which are just pointers to the range in the
20598 -- original tree, this would otherwise be an orphan).
20600 -- The tree is left unanalyzed. When the type is frozen, the processing
20601 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
20602 -- analyzed, and uses this as an indication that it should complete
20603 -- work on the range (it will know the final small and size values).
20605 procedure Set_Fixed_Range
20611 S : constant Node_Id :=
20613 Low_Bound => Make_Real_Literal (Loc, Lo),
20614 High_Bound => Make_Real_Literal (Loc, Hi));
20616 Set_Scalar_Range (E, S);
20619 -- Before the freeze point, the bounds of a fixed point are universal
20620 -- and carry the corresponding type.
20622 Set_Etype (Low_Bound (S), Universal_Real);
20623 Set_Etype (High_Bound (S), Universal_Real);
20624 end Set_Fixed_Range;
20626 ----------------------------------
20627 -- Set_Scalar_Range_For_Subtype --
20628 ----------------------------------
20630 procedure Set_Scalar_Range_For_Subtype
20631 (Def_Id : Entity_Id;
20635 Kind : constant Entity_Kind := Ekind (Def_Id);
20638 -- Defend against previous error
20640 if Nkind (R) = N_Error then
20644 Set_Scalar_Range (Def_Id, R);
20646 -- We need to link the range into the tree before resolving it so
20647 -- that types that are referenced, including importantly the subtype
20648 -- itself, are properly frozen (Freeze_Expression requires that the
20649 -- expression be properly linked into the tree). Of course if it is
20650 -- already linked in, then we do not disturb the current link.
20652 if No (Parent (R)) then
20653 Set_Parent (R, Def_Id);
20656 -- Reset the kind of the subtype during analysis of the range, to
20657 -- catch possible premature use in the bounds themselves.
20659 Set_Ekind (Def_Id, E_Void);
20660 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
20661 Set_Ekind (Def_Id, Kind);
20662 end Set_Scalar_Range_For_Subtype;
20664 --------------------------------------------------------
20665 -- Set_Stored_Constraint_From_Discriminant_Constraint --
20666 --------------------------------------------------------
20668 procedure Set_Stored_Constraint_From_Discriminant_Constraint
20672 -- Make sure set if encountered during Expand_To_Stored_Constraint
20674 Set_Stored_Constraint (E, No_Elist);
20676 -- Give it the right value
20678 if Is_Constrained (E) and then Has_Discriminants (E) then
20679 Set_Stored_Constraint (E,
20680 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
20682 end Set_Stored_Constraint_From_Discriminant_Constraint;
20684 -------------------------------------
20685 -- Signed_Integer_Type_Declaration --
20686 -------------------------------------
20688 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
20689 Implicit_Base : Entity_Id;
20690 Base_Typ : Entity_Id;
20693 Errs : Boolean := False;
20697 function Can_Derive_From (E : Entity_Id) return Boolean;
20698 -- Determine whether given bounds allow derivation from specified type
20700 procedure Check_Bound (Expr : Node_Id);
20701 -- Check bound to make sure it is integral and static. If not, post
20702 -- appropriate error message and set Errs flag
20704 ---------------------
20705 -- Can_Derive_From --
20706 ---------------------
20708 -- Note we check both bounds against both end values, to deal with
20709 -- strange types like ones with a range of 0 .. -12341234.
20711 function Can_Derive_From (E : Entity_Id) return Boolean is
20712 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
20713 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
20715 return Lo <= Lo_Val and then Lo_Val <= Hi
20717 Lo <= Hi_Val and then Hi_Val <= Hi;
20718 end Can_Derive_From;
20724 procedure Check_Bound (Expr : Node_Id) is
20726 -- If a range constraint is used as an integer type definition, each
20727 -- bound of the range must be defined by a static expression of some
20728 -- integer type, but the two bounds need not have the same integer
20729 -- type (Negative bounds are allowed.) (RM 3.5.4)
20731 if not Is_Integer_Type (Etype (Expr)) then
20733 ("integer type definition bounds must be of integer type", Expr);
20736 elsif not Is_OK_Static_Expression (Expr) then
20737 Flag_Non_Static_Expr
20738 ("non-static expression used for integer type bound!", Expr);
20741 -- The bounds are folded into literals, and we set their type to be
20742 -- universal, to avoid typing difficulties: we cannot set the type
20743 -- of the literal to the new type, because this would be a forward
20744 -- reference for the back end, and if the original type is user-
20745 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
20748 if Is_Entity_Name (Expr) then
20749 Fold_Uint (Expr, Expr_Value (Expr), True);
20752 Set_Etype (Expr, Universal_Integer);
20756 -- Start of processing for Signed_Integer_Type_Declaration
20759 -- Create an anonymous base type
20762 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
20764 -- Analyze and check the bounds, they can be of any integer type
20766 Lo := Low_Bound (Def);
20767 Hi := High_Bound (Def);
20769 -- Arbitrarily use Integer as the type if either bound had an error
20771 if Hi = Error or else Lo = Error then
20772 Base_Typ := Any_Integer;
20773 Set_Error_Posted (T, True);
20775 -- Here both bounds are OK expressions
20778 Analyze_And_Resolve (Lo, Any_Integer);
20779 Analyze_And_Resolve (Hi, Any_Integer);
20785 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20786 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20789 -- Find type to derive from
20791 Lo_Val := Expr_Value (Lo);
20792 Hi_Val := Expr_Value (Hi);
20794 if Can_Derive_From (Standard_Short_Short_Integer) then
20795 Base_Typ := Base_Type (Standard_Short_Short_Integer);
20797 elsif Can_Derive_From (Standard_Short_Integer) then
20798 Base_Typ := Base_Type (Standard_Short_Integer);
20800 elsif Can_Derive_From (Standard_Integer) then
20801 Base_Typ := Base_Type (Standard_Integer);
20803 elsif Can_Derive_From (Standard_Long_Integer) then
20804 Base_Typ := Base_Type (Standard_Long_Integer);
20806 elsif Can_Derive_From (Standard_Long_Long_Integer) then
20807 Check_Restriction (No_Long_Long_Integers, Def);
20808 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20811 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20812 Error_Msg_N ("integer type definition bounds out of range", Def);
20813 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20814 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20818 -- Complete both implicit base and declared first subtype entities
20820 Set_Etype (Implicit_Base, Base_Typ);
20821 Set_Size_Info (Implicit_Base, (Base_Typ));
20822 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
20823 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
20825 Set_Ekind (T, E_Signed_Integer_Subtype);
20826 Set_Etype (T, Implicit_Base);
20828 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
20830 Set_Size_Info (T, (Implicit_Base));
20831 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
20832 Set_Scalar_Range (T, Def);
20833 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
20834 Set_Is_Constrained (T);
20835 end Signed_Integer_Type_Declaration;