1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Contracts; use Contracts;
30 with Debug; use Debug;
31 with Elists; use Elists;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Eval_Fat; use Eval_Fat;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Dist; use Exp_Dist;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Fname; use Fname;
43 with Freeze; use Freeze;
44 with Ghost; use Ghost;
45 with Itypes; use Itypes;
46 with Layout; use Layout;
48 with Lib.Xref; use Lib.Xref;
49 with Namet; use Namet;
50 with Nmake; use Nmake;
52 with Restrict; use Restrict;
53 with Rident; use Rident;
54 with Rtsfind; use Rtsfind;
56 with Sem_Aux; use Sem_Aux;
57 with Sem_Case; use Sem_Case;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch6; use Sem_Ch6;
60 with Sem_Ch7; use Sem_Ch7;
61 with Sem_Ch8; use Sem_Ch8;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Dim; use Sem_Dim;
64 with Sem_Disp; use Sem_Disp;
65 with Sem_Dist; use Sem_Dist;
66 with Sem_Elim; use Sem_Elim;
67 with Sem_Eval; use Sem_Eval;
68 with Sem_Mech; use Sem_Mech;
69 with Sem_Res; use Sem_Res;
70 with Sem_Smem; use Sem_Smem;
71 with Sem_Type; use Sem_Type;
72 with Sem_Util; use Sem_Util;
73 with Sem_Warn; use Sem_Warn;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinput; use Sinput;
77 with Snames; use Snames;
78 with Targparm; use Targparm;
79 with Tbuild; use Tbuild;
80 with Ttypes; use Ttypes;
81 with Uintp; use Uintp;
82 with Urealp; use Urealp;
84 package body Sem_Ch3 is
86 -----------------------
87 -- Local Subprograms --
88 -----------------------
90 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
91 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
92 -- abstract interface types implemented by a record type or a derived
95 procedure Build_Derived_Type
97 Parent_Type : Entity_Id;
98 Derived_Type : Entity_Id;
99 Is_Completion : Boolean;
100 Derive_Subps : Boolean := True);
101 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
102 -- the N_Full_Type_Declaration node containing the derived type definition.
103 -- Parent_Type is the entity for the parent type in the derived type
104 -- definition and Derived_Type the actual derived type. Is_Completion must
105 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
106 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
107 -- completion of a private type declaration. If Is_Completion is set to
108 -- True, N is the completion of a private type declaration and Derived_Type
109 -- is different from the defining identifier inside N (i.e. Derived_Type /=
110 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
111 -- subprograms should be derived. The only case where this parameter is
112 -- False is when Build_Derived_Type is recursively called to process an
113 -- implicit derived full type for a type derived from a private type (in
114 -- that case the subprograms must only be derived for the private view of
117 -- ??? These flags need a bit of re-examination and re-documentation:
118 -- ??? are they both necessary (both seem related to the recursion)?
120 procedure Build_Derived_Access_Type
122 Parent_Type : Entity_Id;
123 Derived_Type : Entity_Id);
124 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
125 -- create an implicit base if the parent type is constrained or if the
126 -- subtype indication has a constraint.
128 procedure Build_Derived_Array_Type
130 Parent_Type : Entity_Id;
131 Derived_Type : Entity_Id);
132 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
133 -- create an implicit base if the parent type is constrained or if the
134 -- subtype indication has a constraint.
136 procedure Build_Derived_Concurrent_Type
138 Parent_Type : Entity_Id;
139 Derived_Type : Entity_Id);
140 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
141 -- protected type, inherit entries and protected subprograms, check
142 -- legality of discriminant constraints if any.
144 procedure Build_Derived_Enumeration_Type
146 Parent_Type : Entity_Id;
147 Derived_Type : Entity_Id);
148 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
149 -- type, we must create a new list of literals. Types derived from
150 -- Character and [Wide_]Wide_Character are special-cased.
152 procedure Build_Derived_Numeric_Type
154 Parent_Type : Entity_Id;
155 Derived_Type : Entity_Id);
156 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
157 -- an anonymous base type, and propagate constraint to subtype if needed.
159 procedure Build_Derived_Private_Type
161 Parent_Type : Entity_Id;
162 Derived_Type : Entity_Id;
163 Is_Completion : Boolean;
164 Derive_Subps : Boolean := True);
165 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
166 -- because the parent may or may not have a completion, and the derivation
167 -- may itself be a completion.
169 procedure Build_Derived_Record_Type
171 Parent_Type : Entity_Id;
172 Derived_Type : Entity_Id;
173 Derive_Subps : Boolean := True);
174 -- Subsidiary procedure used for tagged and untagged record types
175 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
176 -- All parameters are as in Build_Derived_Type except that N, in
177 -- addition to being an N_Full_Type_Declaration node, can also be an
178 -- N_Private_Extension_Declaration node. See the definition of this routine
179 -- for much more info. Derive_Subps indicates whether subprograms should be
180 -- derived from the parent type. The only case where Derive_Subps is False
181 -- is for an implicit derived full type for a type derived from a private
182 -- type (see Build_Derived_Type).
184 procedure Build_Discriminal (Discrim : Entity_Id);
185 -- Create the discriminal corresponding to discriminant Discrim, that is
186 -- the parameter corresponding to Discrim to be used in initialization
187 -- procedures for the type where Discrim is a discriminant. Discriminals
188 -- are not used during semantic analysis, and are not fully defined
189 -- entities until expansion. Thus they are not given a scope until
190 -- initialization procedures are built.
192 function Build_Discriminant_Constraints
195 Derived_Def : Boolean := False) return Elist_Id;
196 -- Validate discriminant constraints and return the list of the constraints
197 -- in order of discriminant declarations, where T is the discriminated
198 -- unconstrained type. Def is the N_Subtype_Indication node where the
199 -- discriminants constraints for T are specified. Derived_Def is True
200 -- when building the discriminant constraints in a derived type definition
201 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
202 -- type and Def is the constraint "(xxx)" on T and this routine sets the
203 -- Corresponding_Discriminant field of the discriminants in the derived
204 -- type D to point to the corresponding discriminants in the parent type T.
206 procedure Build_Discriminated_Subtype
210 Related_Nod : Node_Id;
211 For_Access : Boolean := False);
212 -- Subsidiary procedure to Constrain_Discriminated_Type and to
213 -- Process_Incomplete_Dependents. Given
215 -- T (a possibly discriminated base type)
216 -- Def_Id (a very partially built subtype for T),
218 -- the call completes Def_Id to be the appropriate E_*_Subtype.
220 -- The Elist is the list of discriminant constraints if any (it is set
221 -- to No_Elist if T is not a discriminated type, and to an empty list if
222 -- T has discriminants but there are no discriminant constraints). The
223 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
224 -- The For_Access says whether or not this subtype is really constraining
225 -- an access type. That is its sole purpose is the designated type of an
226 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
227 -- is built to avoid freezing T when the access subtype is frozen.
229 function Build_Scalar_Bound
232 Der_T : Entity_Id) return Node_Id;
233 -- The bounds of a derived scalar type are conversions of the bounds of
234 -- the parent type. Optimize the representation if the bounds are literals.
235 -- Needs a more complete spec--what are the parameters exactly, and what
236 -- exactly is the returned value, and how is Bound affected???
238 procedure Build_Underlying_Full_View
242 -- If the completion of a private type is itself derived from a private
243 -- type, or if the full view of a private subtype is itself private, the
244 -- back-end has no way to compute the actual size of this type. We build
245 -- an internal subtype declaration of the proper parent type to convey
246 -- this information. This extra mechanism is needed because a full
247 -- view cannot itself have a full view (it would get clobbered during
250 procedure Check_Access_Discriminant_Requires_Limited
253 -- Check the restriction that the type to which an access discriminant
254 -- belongs must be a concurrent type or a descendant of a type with
255 -- the reserved word 'limited' in its declaration.
257 procedure Check_Anonymous_Access_Components
261 Comp_List : Node_Id);
262 -- Ada 2005 AI-382: an access component in a record definition can refer to
263 -- the enclosing record, in which case it denotes the type itself, and not
264 -- the current instance of the type. We create an anonymous access type for
265 -- the component, and flag it as an access to a component, so accessibility
266 -- checks are properly performed on it. The declaration of the access type
267 -- is placed ahead of that of the record to prevent order-of-elaboration
268 -- circularity issues in Gigi. We create an incomplete type for the record
269 -- declaration, which is the designated type of the anonymous access.
271 procedure Check_Delta_Expression (E : Node_Id);
272 -- Check that the expression represented by E is suitable for use as a
273 -- delta expression, i.e. it is of real type and is static.
275 procedure Check_Digits_Expression (E : Node_Id);
276 -- Check that the expression represented by E is suitable for use as a
277 -- digits expression, i.e. it is of integer type, positive and static.
279 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
280 -- Validate the initialization of an object declaration. T is the required
281 -- type, and Exp is the initialization expression.
283 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
284 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
286 procedure Check_Or_Process_Discriminants
289 Prev : Entity_Id := Empty);
290 -- If N is the full declaration of the completion T of an incomplete or
291 -- private type, check its discriminants (which are already known to be
292 -- conformant with those of the partial view, see Find_Type_Name),
293 -- otherwise process them. Prev is the entity of the partial declaration,
296 procedure Check_Real_Bound (Bound : Node_Id);
297 -- Check given bound for being of real type and static. If not, post an
298 -- appropriate message, and rewrite the bound with the real literal zero.
300 procedure Constant_Redeclaration
304 -- Various checks on legality of full declaration of deferred constant.
305 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
306 -- node. The caller has not yet set any attributes of this entity.
308 function Contain_Interface
310 Ifaces : Elist_Id) return Boolean;
311 -- Ada 2005: Determine whether Iface is present in the list Ifaces
313 procedure Convert_Scalar_Bounds
315 Parent_Type : Entity_Id;
316 Derived_Type : Entity_Id;
318 -- For derived scalar types, convert the bounds in the type definition to
319 -- the derived type, and complete their analysis. Given a constraint of the
320 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
321 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
322 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
323 -- subtype are conversions of those bounds to the derived_type, so that
324 -- their typing is consistent.
326 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
327 -- Copies attributes from array base type T2 to array base type T1. Copies
328 -- only attributes that apply to base types, but not subtypes.
330 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
331 -- Copies attributes from array subtype T2 to array subtype T1. Copies
332 -- attributes that apply to both subtypes and base types.
334 procedure Create_Constrained_Components
338 Constraints : Elist_Id);
339 -- Build the list of entities for a constrained discriminated record
340 -- subtype. If a component depends on a discriminant, replace its subtype
341 -- using the discriminant values in the discriminant constraint. Subt
342 -- is the defining identifier for the subtype whose list of constrained
343 -- entities we will create. Decl_Node is the type declaration node where
344 -- we will attach all the itypes created. Typ is the base discriminated
345 -- type for the subtype Subt. Constraints is the list of discriminant
346 -- constraints for Typ.
348 function Constrain_Component_Type
350 Constrained_Typ : Entity_Id;
351 Related_Node : Node_Id;
353 Constraints : Elist_Id) return Entity_Id;
354 -- Given a discriminated base type Typ, a list of discriminant constraints,
355 -- Constraints, for Typ and a component Comp of Typ, create and return the
356 -- type corresponding to Etype (Comp) where all discriminant references
357 -- are replaced with the corresponding constraint. If Etype (Comp) contains
358 -- no discriminant references then it is returned as-is. Constrained_Typ
359 -- is the final constrained subtype to which the constrained component
360 -- belongs. Related_Node is the node where we attach all created itypes.
362 procedure Constrain_Access
363 (Def_Id : in out Entity_Id;
365 Related_Nod : Node_Id);
366 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
367 -- an anonymous type created for a subtype indication. In that case it is
368 -- created in the procedure and attached to Related_Nod.
370 procedure Constrain_Array
371 (Def_Id : in out Entity_Id;
373 Related_Nod : Node_Id;
374 Related_Id : Entity_Id;
376 -- Apply a list of index constraints to an unconstrained array type. The
377 -- first parameter is the entity for the resulting subtype. A value of
378 -- Empty for Def_Id indicates that an implicit type must be created, but
379 -- creation is delayed (and must be done by this procedure) because other
380 -- subsidiary implicit types must be created first (which is why Def_Id
381 -- is an in/out parameter). The second parameter is a subtype indication
382 -- node for the constrained array to be created (e.g. something of the
383 -- form string (1 .. 10)). Related_Nod gives the place where this type
384 -- has to be inserted in the tree. The Related_Id and Suffix parameters
385 -- are used to build the associated Implicit type name.
387 procedure Constrain_Concurrent
388 (Def_Id : in out Entity_Id;
390 Related_Nod : Node_Id;
391 Related_Id : Entity_Id;
393 -- Apply list of discriminant constraints to an unconstrained concurrent
396 -- SI is the N_Subtype_Indication node containing the constraint and
397 -- the unconstrained type to constrain.
399 -- Def_Id is the entity for the resulting constrained subtype. A value
400 -- of Empty for Def_Id indicates that an implicit type must be created,
401 -- but creation is delayed (and must be done by this procedure) because
402 -- other subsidiary implicit types must be created first (which is why
403 -- Def_Id is an in/out parameter).
405 -- Related_Nod gives the place where this type has to be inserted
408 -- The last two arguments are used to create its external name if needed.
410 function Constrain_Corresponding_Record
411 (Prot_Subt : Entity_Id;
412 Corr_Rec : Entity_Id;
413 Related_Nod : Node_Id) return Entity_Id;
414 -- When constraining a protected type or task type with discriminants,
415 -- constrain the corresponding record with the same discriminant values.
417 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
418 -- Constrain a decimal fixed point type with a digits constraint and/or a
419 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
421 procedure Constrain_Discriminated_Type
424 Related_Nod : Node_Id;
425 For_Access : Boolean := False);
426 -- Process discriminant constraints of composite type. Verify that values
427 -- have been provided for all discriminants, that the original type is
428 -- unconstrained, and that the types of the supplied expressions match
429 -- the discriminant types. The first three parameters are like in routine
430 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
433 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain an enumeration type with a range constraint. This is identical
435 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
437 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
438 -- Constrain a floating point type with either a digits constraint
439 -- and/or a range constraint, building a E_Floating_Point_Subtype.
441 procedure Constrain_Index
444 Related_Nod : Node_Id;
445 Related_Id : Entity_Id;
448 -- Process an index constraint S in a constrained array declaration. The
449 -- constraint can be a subtype name, or a range with or without an explicit
450 -- subtype mark. The index is the corresponding index of the unconstrained
451 -- array. The Related_Id and Suffix parameters are used to build the
452 -- associated Implicit type name.
454 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
455 -- Build subtype of a signed or modular integer type
457 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
458 -- Constrain an ordinary fixed point type with a range constraint, and
459 -- build an E_Ordinary_Fixed_Point_Subtype entity.
461 procedure Copy_And_Swap (Priv, Full : Entity_Id);
462 -- Copy the Priv entity into the entity of its full declaration then swap
463 -- the two entities in such a manner that the former private type is now
464 -- seen as a full type.
466 procedure Decimal_Fixed_Point_Type_Declaration
469 -- Create a new decimal fixed point type, and apply the constraint to
470 -- obtain a subtype of this new type.
472 procedure Complete_Private_Subtype
475 Full_Base : Entity_Id;
476 Related_Nod : Node_Id);
477 -- Complete the implicit full view of a private subtype by setting the
478 -- appropriate semantic fields. If the full view of the parent is a record
479 -- type, build constrained components of subtype.
481 procedure Derive_Progenitor_Subprograms
482 (Parent_Type : Entity_Id;
483 Tagged_Type : Entity_Id);
484 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
485 -- operations of progenitors of Tagged_Type, and replace the subsidiary
486 -- subtypes with Tagged_Type, to build the specs of the inherited interface
487 -- primitives. The derived primitives are aliased to those of the
488 -- interface. This routine takes care also of transferring to the full view
489 -- subprograms associated with the partial view of Tagged_Type that cover
490 -- interface primitives.
492 procedure Derived_Standard_Character
494 Parent_Type : Entity_Id;
495 Derived_Type : Entity_Id);
496 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
497 -- derivations from types Standard.Character and Standard.Wide_Character.
499 procedure Derived_Type_Declaration
502 Is_Completion : Boolean);
503 -- Process a derived type declaration. Build_Derived_Type is invoked
504 -- to process the actual derived type definition. Parameters N and
505 -- Is_Completion have the same meaning as in Build_Derived_Type.
506 -- T is the N_Defining_Identifier for the entity defined in the
507 -- N_Full_Type_Declaration node N, that is T is the derived type.
509 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
510 -- Insert each literal in symbol table, as an overloadable identifier. Each
511 -- enumeration type is mapped into a sequence of integers, and each literal
512 -- is defined as a constant with integer value. If any of the literals are
513 -- character literals, the type is a character type, which means that
514 -- strings are legal aggregates for arrays of components of the type.
516 function Expand_To_Stored_Constraint
518 Constraint : Elist_Id) return Elist_Id;
519 -- Given a constraint (i.e. a list of expressions) on the discriminants of
520 -- Typ, expand it into a constraint on the stored discriminants and return
521 -- the new list of expressions constraining the stored discriminants.
523 function Find_Type_Of_Object
525 Related_Nod : Node_Id) return Entity_Id;
526 -- Get type entity for object referenced by Obj_Def, attaching the implicit
527 -- types generated to Related_Nod.
529 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
530 -- Create a new float and apply the constraint to obtain subtype of it
532 function Has_Range_Constraint (N : Node_Id) return Boolean;
533 -- Given an N_Subtype_Indication node N, return True if a range constraint
534 -- is present, either directly, or as part of a digits or delta constraint.
535 -- In addition, a digits constraint in the decimal case returns True, since
536 -- it establishes a default range if no explicit range is present.
538 function Inherit_Components
540 Parent_Base : Entity_Id;
541 Derived_Base : Entity_Id;
543 Inherit_Discr : Boolean;
544 Discs : Elist_Id) return Elist_Id;
545 -- Called from Build_Derived_Record_Type to inherit the components of
546 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
547 -- For more information on derived types and component inheritance please
548 -- consult the comment above the body of Build_Derived_Record_Type.
550 -- N is the original derived type declaration
552 -- Is_Tagged is set if we are dealing with tagged types
554 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
555 -- Parent_Base, otherwise no discriminants are inherited.
557 -- Discs gives the list of constraints that apply to Parent_Base in the
558 -- derived type declaration. If Discs is set to No_Elist, then we have
559 -- the following situation:
561 -- type Parent (D1..Dn : ..) is [tagged] record ...;
562 -- type Derived is new Parent [with ...];
564 -- which gets treated as
566 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
568 -- For untagged types the returned value is an association list. The list
569 -- starts from the association (Parent_Base => Derived_Base), and then it
570 -- contains a sequence of the associations of the form
572 -- (Old_Component => New_Component),
574 -- where Old_Component is the Entity_Id of a component in Parent_Base and
575 -- New_Component is the Entity_Id of the corresponding component in
576 -- Derived_Base. For untagged records, this association list is needed when
577 -- copying the record declaration for the derived base. In the tagged case
578 -- the value returned is irrelevant.
580 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
581 -- Propagate static and dynamic predicate flags from a parent to the
582 -- subtype in a subtype declaration with and without constraints.
584 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
585 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
586 -- Determine whether subprogram Subp is a procedure subject to pragma
587 -- Extensions_Visible with value False and has at least one controlling
588 -- parameter of mode OUT.
590 function Is_Valid_Constraint_Kind
592 Constraint_Kind : Node_Kind) return Boolean;
593 -- Returns True if it is legal to apply the given kind of constraint to the
594 -- given kind of type (index constraint to an array type, for example).
596 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
597 -- Create new modular type. Verify that modulus is in bounds
599 procedure New_Concatenation_Op (Typ : Entity_Id);
600 -- Create an abbreviated declaration for an operator in order to
601 -- materialize concatenation on array types.
603 procedure Ordinary_Fixed_Point_Type_Declaration
606 -- Create a new ordinary fixed point type, and apply the constraint to
607 -- obtain subtype of it.
609 procedure Prepare_Private_Subtype_Completion
611 Related_Nod : Node_Id);
612 -- Id is a subtype of some private type. Creates the full declaration
613 -- associated with Id whenever possible, i.e. when the full declaration
614 -- of the base type is already known. Records each subtype into
615 -- Private_Dependents of the base type.
617 procedure Process_Incomplete_Dependents
621 -- Process all entities that depend on an incomplete type. There include
622 -- subtypes, subprogram types that mention the incomplete type in their
623 -- profiles, and subprogram with access parameters that designate the
626 -- Inc_T is the defining identifier of an incomplete type declaration, its
627 -- Ekind is E_Incomplete_Type.
629 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
631 -- Full_T is N's defining identifier.
633 -- Subtypes of incomplete types with discriminants are completed when the
634 -- parent type is. This is simpler than private subtypes, because they can
635 -- only appear in the same scope, and there is no need to exchange views.
636 -- Similarly, access_to_subprogram types may have a parameter or a return
637 -- type that is an incomplete type, and that must be replaced with the
640 -- If the full type is tagged, subprogram with access parameters that
641 -- designated the incomplete may be primitive operations of the full type,
642 -- and have to be processed accordingly.
644 procedure Process_Real_Range_Specification (Def : Node_Id);
645 -- Given the type definition for a real type, this procedure processes and
646 -- checks the real range specification of this type definition if one is
647 -- present. If errors are found, error messages are posted, and the
648 -- Real_Range_Specification of Def is reset to Empty.
650 procedure Record_Type_Declaration
654 -- Process a record type declaration (for both untagged and tagged
655 -- records). Parameters T and N are exactly like in procedure
656 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
657 -- for this routine. If this is the completion of an incomplete type
658 -- declaration, Prev is the entity of the incomplete declaration, used for
659 -- cross-referencing. Otherwise Prev = T.
661 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
662 -- This routine is used to process the actual record type definition (both
663 -- for untagged and tagged records). Def is a record type definition node.
664 -- This procedure analyzes the components in this record type definition.
665 -- Prev_T is the entity for the enclosing record type. It is provided so
666 -- that its Has_Task flag can be set if any of the component have Has_Task
667 -- set. If the declaration is the completion of an incomplete type
668 -- declaration, Prev_T is the original incomplete type, whose full view is
671 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
672 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
673 -- build a copy of the declaration tree of the parent, and we create
674 -- independently the list of components for the derived type. Semantic
675 -- information uses the component entities, but record representation
676 -- clauses are validated on the declaration tree. This procedure replaces
677 -- discriminants and components in the declaration with those that have
678 -- been created by Inherit_Components.
680 procedure Set_Fixed_Range
685 -- Build a range node with the given bounds and set it as the Scalar_Range
686 -- of the given fixed-point type entity. Loc is the source location used
687 -- for the constructed range. See body for further details.
689 procedure Set_Scalar_Range_For_Subtype
693 -- This routine is used to set the scalar range field for a subtype given
694 -- Def_Id, the entity for the subtype, and R, the range expression for the
695 -- scalar range. Subt provides the parent subtype to be used to analyze,
696 -- resolve, and check the given range.
698 procedure Set_Default_SSO (T : Entity_Id);
699 -- T is the entity for an array or record being declared. This procedure
700 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
701 -- to the setting of Opt.Default_SSO.
703 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
704 -- Create a new signed integer entity, and apply the constraint to obtain
705 -- the required first named subtype of this type.
707 procedure Set_Stored_Constraint_From_Discriminant_Constraint
709 -- E is some record type. This routine computes E's Stored_Constraint
710 -- from its Discriminant_Constraint.
712 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
713 -- Check that an entity in a list of progenitors is an interface,
714 -- emit error otherwise.
716 -----------------------
717 -- Access_Definition --
718 -----------------------
720 function Access_Definition
721 (Related_Nod : Node_Id;
722 N : Node_Id) return Entity_Id
724 Anon_Type : Entity_Id;
725 Anon_Scope : Entity_Id;
726 Desig_Type : Entity_Id;
727 Enclosing_Prot_Type : Entity_Id := Empty;
730 Check_SPARK_05_Restriction ("access type is not allowed", N);
732 if Is_Entry (Current_Scope)
733 and then Is_Task_Type (Etype (Scope (Current_Scope)))
735 Error_Msg_N ("task entries cannot have access parameters", N);
739 -- Ada 2005: For an object declaration the corresponding anonymous
740 -- type is declared in the current scope.
742 -- If the access definition is the return type of another access to
743 -- function, scope is the current one, because it is the one of the
744 -- current type declaration, except for the pathological case below.
746 if Nkind_In (Related_Nod, N_Object_Declaration,
747 N_Access_Function_Definition)
749 Anon_Scope := Current_Scope;
751 -- A pathological case: function returning access functions that
752 -- return access functions, etc. Each anonymous access type created
753 -- is in the enclosing scope of the outermost function.
760 while Nkind_In (Par, N_Access_Function_Definition,
766 if Nkind (Par) = N_Function_Specification then
767 Anon_Scope := Scope (Defining_Entity (Par));
771 -- For the anonymous function result case, retrieve the scope of the
772 -- function specification's associated entity rather than using the
773 -- current scope. The current scope will be the function itself if the
774 -- formal part is currently being analyzed, but will be the parent scope
775 -- in the case of a parameterless function, and we always want to use
776 -- the function's parent scope. Finally, if the function is a child
777 -- unit, we must traverse the tree to retrieve the proper entity.
779 elsif Nkind (Related_Nod) = N_Function_Specification
780 and then Nkind (Parent (N)) /= N_Parameter_Specification
782 -- If the current scope is a protected type, the anonymous access
783 -- is associated with one of the protected operations, and must
784 -- be available in the scope that encloses the protected declaration.
785 -- Otherwise the type is in the scope enclosing the subprogram.
787 -- If the function has formals, The return type of a subprogram
788 -- declaration is analyzed in the scope of the subprogram (see
789 -- Process_Formals) and thus the protected type, if present, is
790 -- the scope of the current function scope.
792 if Ekind (Current_Scope) = E_Protected_Type then
793 Enclosing_Prot_Type := Current_Scope;
795 elsif Ekind (Current_Scope) = E_Function
796 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
798 Enclosing_Prot_Type := Scope (Current_Scope);
801 if Present (Enclosing_Prot_Type) then
802 Anon_Scope := Scope (Enclosing_Prot_Type);
805 Anon_Scope := Scope (Defining_Entity (Related_Nod));
808 -- For an access type definition, if the current scope is a child
809 -- unit it is the scope of the type.
811 elsif Is_Compilation_Unit (Current_Scope) then
812 Anon_Scope := Current_Scope;
814 -- For access formals, access components, and access discriminants, the
815 -- scope is that of the enclosing declaration,
818 Anon_Scope := Scope (Current_Scope);
823 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
826 and then Ada_Version >= Ada_2005
828 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
831 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
832 -- the corresponding semantic routine
834 if Present (Access_To_Subprogram_Definition (N)) then
836 -- Compiler runtime units are compiled in Ada 2005 mode when building
837 -- the runtime library but must also be compilable in Ada 95 mode
838 -- (when bootstrapping the compiler).
840 Check_Compiler_Unit ("anonymous access to subprogram", N);
842 Access_Subprogram_Declaration
843 (T_Name => Anon_Type,
844 T_Def => Access_To_Subprogram_Definition (N));
846 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
848 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
850 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
853 Set_Can_Use_Internal_Rep
854 (Anon_Type, not Always_Compatible_Rep_On_Target);
856 -- If the anonymous access is associated with a protected operation,
857 -- create a reference to it after the enclosing protected definition
858 -- because the itype will be used in the subsequent bodies.
860 -- If the anonymous access itself is protected, a full type
861 -- declaratiton will be created for it, so that the equivalent
862 -- record type can be constructed. For further details, see
863 -- Replace_Anonymous_Access_To_Protected-Subprogram.
865 if Ekind (Current_Scope) = E_Protected_Type
866 and then not Protected_Present (Access_To_Subprogram_Definition (N))
868 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
874 Find_Type (Subtype_Mark (N));
875 Desig_Type := Entity (Subtype_Mark (N));
877 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
878 Set_Etype (Anon_Type, Anon_Type);
880 -- Make sure the anonymous access type has size and alignment fields
881 -- set, as required by gigi. This is necessary in the case of the
882 -- Task_Body_Procedure.
884 if not Has_Private_Component (Desig_Type) then
885 Layout_Type (Anon_Type);
888 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
889 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
890 -- the null value is allowed. In Ada 95 the null value is never allowed.
892 if Ada_Version >= Ada_2005 then
893 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
895 Set_Can_Never_Be_Null (Anon_Type, True);
898 -- The anonymous access type is as public as the discriminated type or
899 -- subprogram that defines it. It is imported (for back-end purposes)
900 -- if the designated type is.
902 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
904 -- Ada 2005 (AI-231): Propagate the access-constant attribute
906 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
908 -- The context is either a subprogram declaration, object declaration,
909 -- or an access discriminant, in a private or a full type declaration.
910 -- In the case of a subprogram, if the designated type is incomplete,
911 -- the operation will be a primitive operation of the full type, to be
912 -- updated subsequently. If the type is imported through a limited_with
913 -- clause, the subprogram is not a primitive operation of the type
914 -- (which is declared elsewhere in some other scope).
916 if Ekind (Desig_Type) = E_Incomplete_Type
917 and then not From_Limited_With (Desig_Type)
918 and then Is_Overloadable (Current_Scope)
920 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
921 Set_Has_Delayed_Freeze (Current_Scope);
924 -- Ada 2005: If the designated type is an interface that may contain
925 -- tasks, create a Master entity for the declaration. This must be done
926 -- before expansion of the full declaration, because the declaration may
927 -- include an expression that is an allocator, whose expansion needs the
928 -- proper Master for the created tasks.
930 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
932 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
934 Build_Class_Wide_Master (Anon_Type);
936 -- Similarly, if the type is an anonymous access that designates
937 -- tasks, create a master entity for it in the current context.
939 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
941 Build_Master_Entity (Defining_Identifier (Related_Nod));
942 Build_Master_Renaming (Anon_Type);
946 -- For a private component of a protected type, it is imperative that
947 -- the back-end elaborate the type immediately after the protected
948 -- declaration, because this type will be used in the declarations
949 -- created for the component within each protected body, so we must
950 -- create an itype reference for it now.
952 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
953 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
955 -- Similarly, if the access definition is the return result of a
956 -- function, create an itype reference for it because it will be used
957 -- within the function body. For a regular function that is not a
958 -- compilation unit, insert reference after the declaration. For a
959 -- protected operation, insert it after the enclosing protected type
960 -- declaration. In either case, do not create a reference for a type
961 -- obtained through a limited_with clause, because this would introduce
962 -- semantic dependencies.
964 -- Similarly, do not create a reference if the designated type is a
965 -- generic formal, because no use of it will reach the backend.
967 elsif Nkind (Related_Nod) = N_Function_Specification
968 and then not From_Limited_With (Desig_Type)
969 and then not Is_Generic_Type (Desig_Type)
971 if Present (Enclosing_Prot_Type) then
972 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
974 elsif Is_List_Member (Parent (Related_Nod))
975 and then Nkind (Parent (N)) /= N_Parameter_Specification
977 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
980 -- Finally, create an itype reference for an object declaration of an
981 -- anonymous access type. This is strictly necessary only for deferred
982 -- constants, but in any case will avoid out-of-scope problems in the
985 elsif Nkind (Related_Nod) = N_Object_Declaration then
986 Build_Itype_Reference (Anon_Type, Related_Nod);
990 end Access_Definition;
992 -----------------------------------
993 -- Access_Subprogram_Declaration --
994 -----------------------------------
996 procedure Access_Subprogram_Declaration
1000 procedure Check_For_Premature_Usage (Def : Node_Id);
1001 -- Check that type T_Name is not used, directly or recursively, as a
1002 -- parameter or a return type in Def. Def is either a subtype, an
1003 -- access_definition, or an access_to_subprogram_definition.
1005 -------------------------------
1006 -- Check_For_Premature_Usage --
1007 -------------------------------
1009 procedure Check_For_Premature_Usage (Def : Node_Id) is
1013 -- Check for a subtype mark
1015 if Nkind (Def) in N_Has_Etype then
1016 if Etype (Def) = T_Name then
1018 ("type& cannot be used before end of its declaration", Def);
1021 -- If this is not a subtype, then this is an access_definition
1023 elsif Nkind (Def) = N_Access_Definition then
1024 if Present (Access_To_Subprogram_Definition (Def)) then
1025 Check_For_Premature_Usage
1026 (Access_To_Subprogram_Definition (Def));
1028 Check_For_Premature_Usage (Subtype_Mark (Def));
1031 -- The only cases left are N_Access_Function_Definition and
1032 -- N_Access_Procedure_Definition.
1035 if Present (Parameter_Specifications (Def)) then
1036 Param := First (Parameter_Specifications (Def));
1037 while Present (Param) loop
1038 Check_For_Premature_Usage (Parameter_Type (Param));
1039 Param := Next (Param);
1043 if Nkind (Def) = N_Access_Function_Definition then
1044 Check_For_Premature_Usage (Result_Definition (Def));
1047 end Check_For_Premature_Usage;
1051 Formals : constant List_Id := Parameter_Specifications (T_Def);
1054 Desig_Type : constant Entity_Id :=
1055 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1057 -- Start of processing for Access_Subprogram_Declaration
1060 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1062 -- Associate the Itype node with the inner full-type declaration or
1063 -- subprogram spec or entry body. This is required to handle nested
1064 -- anonymous declarations. For example:
1067 -- (X : access procedure
1068 -- (Y : access procedure
1071 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1072 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1073 N_Private_Type_Declaration,
1074 N_Private_Extension_Declaration,
1075 N_Procedure_Specification,
1076 N_Function_Specification,
1080 Nkind_In (D_Ityp, N_Object_Declaration,
1081 N_Object_Renaming_Declaration,
1082 N_Formal_Object_Declaration,
1083 N_Formal_Type_Declaration,
1084 N_Task_Type_Declaration,
1085 N_Protected_Type_Declaration))
1087 D_Ityp := Parent (D_Ityp);
1088 pragma Assert (D_Ityp /= Empty);
1091 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1093 if Nkind_In (D_Ityp, N_Procedure_Specification,
1094 N_Function_Specification)
1096 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1098 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1099 N_Object_Declaration,
1100 N_Object_Renaming_Declaration,
1101 N_Formal_Type_Declaration)
1103 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1106 if Nkind (T_Def) = N_Access_Function_Definition then
1107 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1109 Acc : constant Node_Id := Result_Definition (T_Def);
1112 if Present (Access_To_Subprogram_Definition (Acc))
1114 Protected_Present (Access_To_Subprogram_Definition (Acc))
1118 Replace_Anonymous_Access_To_Protected_Subprogram
1124 Access_Definition (T_Def, Result_Definition (T_Def)));
1129 Analyze (Result_Definition (T_Def));
1132 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1135 -- If a null exclusion is imposed on the result type, then
1136 -- create a null-excluding itype (an access subtype) and use
1137 -- it as the function's Etype.
1139 if Is_Access_Type (Typ)
1140 and then Null_Exclusion_In_Return_Present (T_Def)
1142 Set_Etype (Desig_Type,
1143 Create_Null_Excluding_Itype
1145 Related_Nod => T_Def,
1146 Scope_Id => Current_Scope));
1149 if From_Limited_With (Typ) then
1151 -- AI05-151: Incomplete types are allowed in all basic
1152 -- declarations, including access to subprograms.
1154 if Ada_Version >= Ada_2012 then
1159 ("illegal use of incomplete type&",
1160 Result_Definition (T_Def), Typ);
1163 elsif Ekind (Current_Scope) = E_Package
1164 and then In_Private_Part (Current_Scope)
1166 if Ekind (Typ) = E_Incomplete_Type then
1167 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1169 elsif Is_Class_Wide_Type (Typ)
1170 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1173 (Desig_Type, Private_Dependents (Etype (Typ)));
1177 Set_Etype (Desig_Type, Typ);
1182 if not (Is_Type (Etype (Desig_Type))) then
1184 ("expect type in function specification",
1185 Result_Definition (T_Def));
1189 Set_Etype (Desig_Type, Standard_Void_Type);
1192 if Present (Formals) then
1193 Push_Scope (Desig_Type);
1195 -- Some special tests here. These special tests can be removed
1196 -- if and when Itypes always have proper parent pointers to their
1199 -- Special test 1) Link defining_identifier of formals. Required by
1200 -- First_Formal to provide its functionality.
1206 F := First (Formals);
1208 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1209 -- when it is part of an unconstrained type and subtype expansion
1210 -- is disabled. To avoid back-end problems with shared profiles,
1211 -- use previous subprogram type as the designated type, and then
1212 -- remove scope added above.
1214 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1216 Set_Etype (T_Name, T_Name);
1217 Init_Size_Align (T_Name);
1218 Set_Directly_Designated_Type (T_Name,
1219 Scope (Defining_Identifier (F)));
1224 while Present (F) loop
1225 if No (Parent (Defining_Identifier (F))) then
1226 Set_Parent (Defining_Identifier (F), F);
1233 Process_Formals (Formals, Parent (T_Def));
1235 -- Special test 2) End_Scope requires that the parent pointer be set
1236 -- to something reasonable, but Itypes don't have parent pointers. So
1237 -- we set it and then unset it ???
1239 Set_Parent (Desig_Type, T_Name);
1241 Set_Parent (Desig_Type, Empty);
1244 -- Check for premature usage of the type being defined
1246 Check_For_Premature_Usage (T_Def);
1248 -- The return type and/or any parameter type may be incomplete. Mark the
1249 -- subprogram_type as depending on the incomplete type, so that it can
1250 -- be updated when the full type declaration is seen. This only applies
1251 -- to incomplete types declared in some enclosing scope, not to limited
1252 -- views from other packages.
1254 -- Prior to Ada 2012, access to functions can only have in_parameters.
1256 if Present (Formals) then
1257 Formal := First_Formal (Desig_Type);
1258 while Present (Formal) loop
1259 if Ekind (Formal) /= E_In_Parameter
1260 and then Nkind (T_Def) = N_Access_Function_Definition
1261 and then Ada_Version < Ada_2012
1263 Error_Msg_N ("functions can only have IN parameters", Formal);
1266 if Ekind (Etype (Formal)) = E_Incomplete_Type
1267 and then In_Open_Scopes (Scope (Etype (Formal)))
1269 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1270 Set_Has_Delayed_Freeze (Desig_Type);
1273 Next_Formal (Formal);
1277 -- Check whether an indirect call without actuals may be possible. This
1278 -- is used when resolving calls whose result is then indexed.
1280 May_Need_Actuals (Desig_Type);
1282 -- If the return type is incomplete, this is legal as long as the type
1283 -- is declared in the current scope and will be completed in it (rather
1284 -- than being part of limited view).
1286 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1287 and then not Has_Delayed_Freeze (Desig_Type)
1288 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1290 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1291 Set_Has_Delayed_Freeze (Desig_Type);
1294 Check_Delayed_Subprogram (Desig_Type);
1296 if Protected_Present (T_Def) then
1297 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1298 Set_Convention (Desig_Type, Convention_Protected);
1300 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1303 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1305 Set_Etype (T_Name, T_Name);
1306 Init_Size_Align (T_Name);
1307 Set_Directly_Designated_Type (T_Name, Desig_Type);
1309 Generate_Reference_To_Formals (T_Name);
1311 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1313 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1315 Check_Restriction (No_Access_Subprograms, T_Def);
1316 end Access_Subprogram_Declaration;
1318 ----------------------------
1319 -- Access_Type_Declaration --
1320 ----------------------------
1322 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1323 P : constant Node_Id := Parent (Def);
1324 S : constant Node_Id := Subtype_Indication (Def);
1326 Full_Desig : Entity_Id;
1329 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1331 -- Check for permissible use of incomplete type
1333 if Nkind (S) /= N_Subtype_Indication then
1336 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1337 Set_Directly_Designated_Type (T, Entity (S));
1339 -- If the designated type is a limited view, we cannot tell if
1340 -- the full view contains tasks, and there is no way to handle
1341 -- that full view in a client. We create a master entity for the
1342 -- scope, which will be used when a client determines that one
1345 if From_Limited_With (Entity (S))
1346 and then not Is_Class_Wide_Type (Entity (S))
1348 Set_Ekind (T, E_Access_Type);
1349 Build_Master_Entity (T);
1350 Build_Master_Renaming (T);
1354 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1357 -- If the access definition is of the form: ACCESS NOT NULL ..
1358 -- the subtype indication must be of an access type. Create
1359 -- a null-excluding subtype of it.
1361 if Null_Excluding_Subtype (Def) then
1362 if not Is_Access_Type (Entity (S)) then
1363 Error_Msg_N ("null exclusion must apply to access type", Def);
1367 Loc : constant Source_Ptr := Sloc (S);
1369 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1373 Make_Subtype_Declaration (Loc,
1374 Defining_Identifier => Nam,
1375 Subtype_Indication =>
1376 New_Occurrence_Of (Entity (S), Loc));
1377 Set_Null_Exclusion_Present (Decl);
1378 Insert_Before (Parent (Def), Decl);
1380 Set_Entity (S, Nam);
1386 Set_Directly_Designated_Type (T,
1387 Process_Subtype (S, P, T, 'P'));
1390 if All_Present (Def) or Constant_Present (Def) then
1391 Set_Ekind (T, E_General_Access_Type);
1393 Set_Ekind (T, E_Access_Type);
1396 Full_Desig := Designated_Type (T);
1398 if Base_Type (Full_Desig) = T then
1399 Error_Msg_N ("access type cannot designate itself", S);
1401 -- In Ada 2005, the type may have a limited view through some unit in
1402 -- its own context, allowing the following circularity that cannot be
1403 -- detected earlier.
1405 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1408 ("access type cannot designate its own class-wide type", S);
1410 -- Clean up indication of tagged status to prevent cascaded errors
1412 Set_Is_Tagged_Type (T, False);
1417 -- If the type has appeared already in a with_type clause, it is frozen
1418 -- and the pointer size is already set. Else, initialize.
1420 if not From_Limited_With (T) then
1421 Init_Size_Align (T);
1424 -- Note that Has_Task is always false, since the access type itself
1425 -- is not a task type. See Einfo for more description on this point.
1426 -- Exactly the same consideration applies to Has_Controlled_Component
1427 -- and to Has_Protected.
1429 Set_Has_Task (T, False);
1430 Set_Has_Protected (T, False);
1431 Set_Has_Timing_Event (T, False);
1432 Set_Has_Controlled_Component (T, False);
1434 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1435 -- problems where an incomplete view of this entity has been previously
1436 -- established by a limited with and an overlaid version of this field
1437 -- (Stored_Constraint) was initialized for the incomplete view.
1439 -- This reset is performed in most cases except where the access type
1440 -- has been created for the purposes of allocating or deallocating a
1441 -- build-in-place object. Such access types have explicitly set pools
1442 -- and finalization masters.
1444 if No (Associated_Storage_Pool (T)) then
1445 Set_Finalization_Master (T, Empty);
1448 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1451 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1452 Set_Is_Access_Constant (T, Constant_Present (Def));
1453 end Access_Type_Declaration;
1455 ----------------------------------
1456 -- Add_Interface_Tag_Components --
1457 ----------------------------------
1459 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1460 Loc : constant Source_Ptr := Sloc (N);
1464 procedure Add_Tag (Iface : Entity_Id);
1465 -- Add tag for one of the progenitor interfaces
1471 procedure Add_Tag (Iface : Entity_Id) is
1478 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1480 -- This is a reasonable place to propagate predicates
1482 if Has_Predicates (Iface) then
1483 Set_Has_Predicates (Typ);
1487 Make_Component_Definition (Loc,
1488 Aliased_Present => True,
1489 Subtype_Indication =>
1490 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1492 Tag := Make_Temporary (Loc, 'V');
1495 Make_Component_Declaration (Loc,
1496 Defining_Identifier => Tag,
1497 Component_Definition => Def);
1499 Analyze_Component_Declaration (Decl);
1501 Set_Analyzed (Decl);
1502 Set_Ekind (Tag, E_Component);
1504 Set_Is_Aliased (Tag);
1505 Set_Related_Type (Tag, Iface);
1506 Init_Component_Location (Tag);
1508 pragma Assert (Is_Frozen (Iface));
1510 Set_DT_Entry_Count (Tag,
1511 DT_Entry_Count (First_Entity (Iface)));
1513 if No (Last_Tag) then
1516 Insert_After (Last_Tag, Decl);
1521 -- If the ancestor has discriminants we need to give special support
1522 -- to store the offset_to_top value of the secondary dispatch tables.
1523 -- For this purpose we add a supplementary component just after the
1524 -- field that contains the tag associated with each secondary DT.
1526 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1528 Make_Component_Definition (Loc,
1529 Subtype_Indication =>
1530 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1532 Offset := Make_Temporary (Loc, 'V');
1535 Make_Component_Declaration (Loc,
1536 Defining_Identifier => Offset,
1537 Component_Definition => Def);
1539 Analyze_Component_Declaration (Decl);
1541 Set_Analyzed (Decl);
1542 Set_Ekind (Offset, E_Component);
1543 Set_Is_Aliased (Offset);
1544 Set_Related_Type (Offset, Iface);
1545 Init_Component_Location (Offset);
1546 Insert_After (Last_Tag, Decl);
1557 -- Start of processing for Add_Interface_Tag_Components
1560 if not RTE_Available (RE_Interface_Tag) then
1562 ("(Ada 2005) interface types not supported by this run-time!",
1567 if Ekind (Typ) /= E_Record_Type
1568 or else (Is_Concurrent_Record_Type (Typ)
1569 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1570 or else (not Is_Concurrent_Record_Type (Typ)
1571 and then No (Interfaces (Typ))
1572 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1577 -- Find the current last tag
1579 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1580 Ext := Record_Extension_Part (Type_Definition (N));
1582 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1583 Ext := Type_Definition (N);
1588 if not (Present (Component_List (Ext))) then
1589 Set_Null_Present (Ext, False);
1591 Set_Component_List (Ext,
1592 Make_Component_List (Loc,
1593 Component_Items => L,
1594 Null_Present => False));
1596 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1597 L := Component_Items
1599 (Record_Extension_Part
1600 (Type_Definition (N))));
1602 L := Component_Items
1604 (Type_Definition (N)));
1607 -- Find the last tag component
1610 while Present (Comp) loop
1611 if Nkind (Comp) = N_Component_Declaration
1612 and then Is_Tag (Defining_Identifier (Comp))
1621 -- At this point L references the list of components and Last_Tag
1622 -- references the current last tag (if any). Now we add the tag
1623 -- corresponding with all the interfaces that are not implemented
1626 if Present (Interfaces (Typ)) then
1627 Elmt := First_Elmt (Interfaces (Typ));
1628 while Present (Elmt) loop
1629 Add_Tag (Node (Elmt));
1633 end Add_Interface_Tag_Components;
1635 -------------------------------------
1636 -- Add_Internal_Interface_Entities --
1637 -------------------------------------
1639 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1642 Iface_Elmt : Elmt_Id;
1643 Iface_Prim : Entity_Id;
1644 Ifaces_List : Elist_Id;
1645 New_Subp : Entity_Id := Empty;
1647 Restore_Scope : Boolean := False;
1650 pragma Assert (Ada_Version >= Ada_2005
1651 and then Is_Record_Type (Tagged_Type)
1652 and then Is_Tagged_Type (Tagged_Type)
1653 and then Has_Interfaces (Tagged_Type)
1654 and then not Is_Interface (Tagged_Type));
1656 -- Ensure that the internal entities are added to the scope of the type
1658 if Scope (Tagged_Type) /= Current_Scope then
1659 Push_Scope (Scope (Tagged_Type));
1660 Restore_Scope := True;
1663 Collect_Interfaces (Tagged_Type, Ifaces_List);
1665 Iface_Elmt := First_Elmt (Ifaces_List);
1666 while Present (Iface_Elmt) loop
1667 Iface := Node (Iface_Elmt);
1669 -- Originally we excluded here from this processing interfaces that
1670 -- are parents of Tagged_Type because their primitives are located
1671 -- in the primary dispatch table (and hence no auxiliary internal
1672 -- entities are required to handle secondary dispatch tables in such
1673 -- case). However, these auxiliary entities are also required to
1674 -- handle derivations of interfaces in formals of generics (see
1675 -- Derive_Subprograms).
1677 Elmt := First_Elmt (Primitive_Operations (Iface));
1678 while Present (Elmt) loop
1679 Iface_Prim := Node (Elmt);
1681 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1683 Find_Primitive_Covering_Interface
1684 (Tagged_Type => Tagged_Type,
1685 Iface_Prim => Iface_Prim);
1687 if No (Prim) and then Serious_Errors_Detected > 0 then
1691 pragma Assert (Present (Prim));
1693 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1694 -- differs from the name of the interface primitive then it is
1695 -- a private primitive inherited from a parent type. In such
1696 -- case, given that Tagged_Type covers the interface, the
1697 -- inherited private primitive becomes visible. For such
1698 -- purpose we add a new entity that renames the inherited
1699 -- private primitive.
1701 if Chars (Prim) /= Chars (Iface_Prim) then
1702 pragma Assert (Has_Suffix (Prim, 'P'));
1704 (New_Subp => New_Subp,
1705 Parent_Subp => Iface_Prim,
1706 Derived_Type => Tagged_Type,
1707 Parent_Type => Iface);
1708 Set_Alias (New_Subp, Prim);
1709 Set_Is_Abstract_Subprogram
1710 (New_Subp, Is_Abstract_Subprogram (Prim));
1714 (New_Subp => New_Subp,
1715 Parent_Subp => Iface_Prim,
1716 Derived_Type => Tagged_Type,
1717 Parent_Type => Iface);
1719 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1720 -- associated with interface types. These entities are
1721 -- only registered in the list of primitives of its
1722 -- corresponding tagged type because they are only used
1723 -- to fill the contents of the secondary dispatch tables.
1724 -- Therefore they are removed from the homonym chains.
1726 Set_Is_Hidden (New_Subp);
1727 Set_Is_Internal (New_Subp);
1728 Set_Alias (New_Subp, Prim);
1729 Set_Is_Abstract_Subprogram
1730 (New_Subp, Is_Abstract_Subprogram (Prim));
1731 Set_Interface_Alias (New_Subp, Iface_Prim);
1733 -- If the returned type is an interface then propagate it to
1734 -- the returned type. Needed by the thunk to generate the code
1735 -- which displaces "this" to reference the corresponding
1736 -- secondary dispatch table in the returned object.
1738 if Is_Interface (Etype (Iface_Prim)) then
1739 Set_Etype (New_Subp, Etype (Iface_Prim));
1742 -- Internal entities associated with interface types are only
1743 -- registered in the list of primitives of the tagged type.
1744 -- They are only used to fill the contents of the secondary
1745 -- dispatch tables. Therefore they are not needed in the
1748 Remove_Homonym (New_Subp);
1750 -- Hidden entities associated with interfaces must have set
1751 -- the Has_Delay_Freeze attribute to ensure that, in case
1752 -- of locally defined tagged types (or compiling with static
1753 -- dispatch tables generation disabled) the corresponding
1754 -- entry of the secondary dispatch table is filled when such
1755 -- an entity is frozen. This is an expansion activity that must
1756 -- be suppressed for ASIS because it leads to gigi elaboration
1757 -- issues in annotate mode.
1759 if not ASIS_Mode then
1760 Set_Has_Delayed_Freeze (New_Subp);
1768 Next_Elmt (Iface_Elmt);
1771 if Restore_Scope then
1774 end Add_Internal_Interface_Entities;
1776 -----------------------------------
1777 -- Analyze_Component_Declaration --
1778 -----------------------------------
1780 procedure Analyze_Component_Declaration (N : Node_Id) is
1781 Loc : constant Source_Ptr := Sloc (Component_Definition (N));
1782 Id : constant Entity_Id := Defining_Identifier (N);
1783 E : constant Node_Id := Expression (N);
1784 Typ : constant Node_Id :=
1785 Subtype_Indication (Component_Definition (N));
1789 function Contains_POC (Constr : Node_Id) return Boolean;
1790 -- Determines whether a constraint uses the discriminant of a record
1791 -- type thus becoming a per-object constraint (POC).
1793 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1794 -- Typ is the type of the current component, check whether this type is
1795 -- a limited type. Used to validate declaration against that of
1796 -- enclosing record.
1802 function Contains_POC (Constr : Node_Id) return Boolean is
1804 -- Prevent cascaded errors
1806 if Error_Posted (Constr) then
1810 case Nkind (Constr) is
1811 when N_Attribute_Reference =>
1812 return Attribute_Name (Constr) = Name_Access
1813 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1815 when N_Discriminant_Association =>
1816 return Denotes_Discriminant (Expression (Constr));
1818 when N_Identifier =>
1819 return Denotes_Discriminant (Constr);
1821 when N_Index_Or_Discriminant_Constraint =>
1826 IDC := First (Constraints (Constr));
1827 while Present (IDC) loop
1829 -- One per-object constraint is sufficient
1831 if Contains_POC (IDC) then
1842 return Denotes_Discriminant (Low_Bound (Constr))
1844 Denotes_Discriminant (High_Bound (Constr));
1846 when N_Range_Constraint =>
1847 return Denotes_Discriminant (Range_Expression (Constr));
1854 ----------------------
1855 -- Is_Known_Limited --
1856 ----------------------
1858 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1859 P : constant Entity_Id := Etype (Typ);
1860 R : constant Entity_Id := Root_Type (Typ);
1863 if Is_Limited_Record (Typ) then
1866 -- If the root type is limited (and not a limited interface)
1867 -- so is the current type
1869 elsif Is_Limited_Record (R)
1870 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1874 -- Else the type may have a limited interface progenitor, but a
1875 -- limited record parent.
1877 elsif R /= P and then Is_Limited_Record (P) then
1883 end Is_Known_Limited;
1885 -- Start of processing for Analyze_Component_Declaration
1888 Generate_Definition (Id);
1891 if Present (Typ) then
1892 T := Find_Type_Of_Object
1893 (Subtype_Indication (Component_Definition (N)), N);
1895 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1896 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1899 -- Ada 2005 (AI-230): Access Definition case
1902 pragma Assert (Present
1903 (Access_Definition (Component_Definition (N))));
1905 T := Access_Definition
1907 N => Access_Definition (Component_Definition (N)));
1908 Set_Is_Local_Anonymous_Access (T);
1910 -- Ada 2005 (AI-254)
1912 if Present (Access_To_Subprogram_Definition
1913 (Access_Definition (Component_Definition (N))))
1914 and then Protected_Present (Access_To_Subprogram_Definition
1916 (Component_Definition (N))))
1918 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1922 -- If the subtype is a constrained subtype of the enclosing record,
1923 -- (which must have a partial view) the back-end does not properly
1924 -- handle the recursion. Rewrite the component declaration with an
1925 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1926 -- the tree directly because side effects have already been removed from
1927 -- discriminant constraints.
1929 if Ekind (T) = E_Access_Subtype
1930 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1931 and then Comes_From_Source (T)
1932 and then Nkind (Parent (T)) = N_Subtype_Declaration
1933 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1936 (Subtype_Indication (Component_Definition (N)),
1937 New_Copy_Tree (Subtype_Indication (Parent (T))));
1938 T := Find_Type_Of_Object
1939 (Subtype_Indication (Component_Definition (N)), N);
1942 -- If the component declaration includes a default expression, then we
1943 -- check that the component is not of a limited type (RM 3.7(5)),
1944 -- and do the special preanalysis of the expression (see section on
1945 -- "Handling of Default and Per-Object Expressions" in the spec of
1949 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1950 Preanalyze_Default_Expression (E, T);
1951 Check_Initialization (T, E);
1953 if Ada_Version >= Ada_2005
1954 and then Ekind (T) = E_Anonymous_Access_Type
1955 and then Etype (E) /= Any_Type
1957 -- Check RM 3.9.2(9): "if the expected type for an expression is
1958 -- an anonymous access-to-specific tagged type, then the object
1959 -- designated by the expression shall not be dynamically tagged
1960 -- unless it is a controlling operand in a call on a dispatching
1963 if Is_Tagged_Type (Directly_Designated_Type (T))
1965 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1967 Ekind (Directly_Designated_Type (Etype (E))) =
1971 ("access to specific tagged type required (RM 3.9.2(9))", E);
1974 -- (Ada 2005: AI-230): Accessibility check for anonymous
1977 if Type_Access_Level (Etype (E)) >
1978 Deepest_Type_Access_Level (T)
1981 ("expression has deeper access level than component " &
1982 "(RM 3.10.2 (12.2))", E);
1985 -- The initialization expression is a reference to an access
1986 -- discriminant. The type of the discriminant is always deeper
1987 -- than any access type.
1989 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1990 and then Is_Entity_Name (E)
1991 and then Ekind (Entity (E)) = E_In_Parameter
1992 and then Present (Discriminal_Link (Entity (E)))
1995 ("discriminant has deeper accessibility level than target",
2001 -- The parent type may be a private view with unknown discriminants,
2002 -- and thus unconstrained. Regular components must be constrained.
2004 if not Is_Definite_Subtype (T) and then Chars (Id) /= Name_uParent then
2005 if Is_Class_Wide_Type (T) then
2007 ("class-wide subtype with unknown discriminants" &
2008 " in component declaration",
2009 Subtype_Indication (Component_Definition (N)));
2012 ("unconstrained subtype in component declaration",
2013 Subtype_Indication (Component_Definition (N)));
2016 -- Components cannot be abstract, except for the special case of
2017 -- the _Parent field (case of extending an abstract tagged type)
2019 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2020 Error_Msg_N ("type of a component cannot be abstract", N);
2024 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2026 -- The component declaration may have a per-object constraint, set
2027 -- the appropriate flag in the defining identifier of the subtype.
2029 if Present (Subtype_Indication (Component_Definition (N))) then
2031 Sindic : constant Node_Id :=
2032 Subtype_Indication (Component_Definition (N));
2034 if Nkind (Sindic) = N_Subtype_Indication
2035 and then Present (Constraint (Sindic))
2036 and then Contains_POC (Constraint (Sindic))
2038 Set_Has_Per_Object_Constraint (Id);
2043 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2044 -- out some static checks.
2046 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2047 Null_Exclusion_Static_Checks (N);
2050 -- If this component is private (or depends on a private type), flag the
2051 -- record type to indicate that some operations are not available.
2053 P := Private_Component (T);
2057 -- Check for circular definitions
2059 if P = Any_Type then
2060 Set_Etype (Id, Any_Type);
2062 -- There is a gap in the visibility of operations only if the
2063 -- component type is not defined in the scope of the record type.
2065 elsif Scope (P) = Scope (Current_Scope) then
2068 elsif Is_Limited_Type (P) then
2069 Set_Is_Limited_Composite (Current_Scope);
2072 Set_Is_Private_Composite (Current_Scope);
2077 and then Is_Limited_Type (T)
2078 and then Chars (Id) /= Name_uParent
2079 and then Is_Tagged_Type (Current_Scope)
2081 if Is_Derived_Type (Current_Scope)
2082 and then not Is_Known_Limited (Current_Scope)
2085 ("extension of nonlimited type cannot have limited components",
2088 if Is_Interface (Root_Type (Current_Scope)) then
2090 ("\limitedness is not inherited from limited interface", N);
2091 Error_Msg_N ("\add LIMITED to type indication", N);
2094 Explain_Limited_Type (T, N);
2095 Set_Etype (Id, Any_Type);
2096 Set_Is_Limited_Composite (Current_Scope, False);
2098 elsif not Is_Derived_Type (Current_Scope)
2099 and then not Is_Limited_Record (Current_Scope)
2100 and then not Is_Concurrent_Type (Current_Scope)
2103 ("nonlimited tagged type cannot have limited components", N);
2104 Explain_Limited_Type (T, N);
2105 Set_Etype (Id, Any_Type);
2106 Set_Is_Limited_Composite (Current_Scope, False);
2110 -- If the component is an unconstrained task or protected type with
2111 -- discriminants, the component and the enclosing record are limited
2112 -- and the component is constrained by its default values. Compute
2113 -- its actual subtype, else it may be allocated the maximum size by
2114 -- the backend, and possibly overflow.
2116 if Is_Concurrent_Type (T)
2117 and then not Is_Constrained (T)
2118 and then Has_Discriminants (T)
2119 and then not Has_Discriminants (Current_Scope)
2122 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2125 Set_Etype (Id, Act_T);
2127 -- Rewrite component definition to use the constrained subtype
2129 Rewrite (Component_Definition (N),
2130 Make_Component_Definition (Loc,
2131 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2135 Set_Original_Record_Component (Id, Id);
2137 if Has_Aspects (N) then
2138 Analyze_Aspect_Specifications (N, Id);
2141 Analyze_Dimension (N);
2142 end Analyze_Component_Declaration;
2144 --------------------------
2145 -- Analyze_Declarations --
2146 --------------------------
2148 procedure Analyze_Declarations (L : List_Id) is
2151 procedure Adjust_Decl;
2152 -- Adjust Decl not to include implicit label declarations, since these
2153 -- have strange Sloc values that result in elaboration check problems.
2154 -- (They have the sloc of the label as found in the source, and that
2155 -- is ahead of the current declarative part).
2157 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id);
2158 -- Create the subprogram bodies which verify the run-time semantics of
2159 -- the pragmas listed below for each elibigle type found in declarative
2160 -- list Decls. The pragmas are:
2162 -- Default_Initial_Condition
2166 -- Context denotes the owner of the declarative list.
2168 procedure Check_Entry_Contracts;
2169 -- Perform a pre-analysis of the pre- and postconditions of an entry
2170 -- declaration. This must be done before full resolution and creation
2171 -- of the parameter block, etc. to catch illegal uses within the
2172 -- contract expression. Full analysis of the expression is done when
2173 -- the contract is processed.
2175 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2176 -- Determine whether Body_Decl denotes the body of a late controlled
2177 -- primitive (either Initialize, Adjust or Finalize). If this is the
2178 -- case, add a proper spec if the body lacks one. The spec is inserted
2179 -- before Body_Decl and immediately analyzed.
2181 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id);
2182 -- Spec_Id is the entity of a package that may define abstract states,
2183 -- and in the case of a child unit, whose ancestors may define abstract
2184 -- states. If the states have partial visible refinement, remove the
2185 -- partial visibility of each constituent at the end of the package
2186 -- spec and body declarations.
2188 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2189 -- Spec_Id is the entity of a package that may define abstract states.
2190 -- If the states have visible refinement, remove the visibility of each
2191 -- constituent at the end of the package body declaration.
2193 procedure Resolve_Aspects;
2194 -- Utility to resolve the expressions of aspects at the end of a list of
2201 procedure Adjust_Decl is
2203 while Present (Prev (Decl))
2204 and then Nkind (Decl) = N_Implicit_Label_Declaration
2210 ----------------------------
2211 -- Build_Assertion_Bodies --
2212 ----------------------------
2214 procedure Build_Assertion_Bodies (Decls : List_Id; Context : Node_Id) is
2215 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id);
2216 -- Create the subprogram bodies which verify the run-time semantics
2217 -- of the pragmas listed below for type Typ. The pragmas are:
2219 -- Default_Initial_Condition
2223 -------------------------------------
2224 -- Build_Assertion_Bodies_For_Type --
2225 -------------------------------------
2227 procedure Build_Assertion_Bodies_For_Type (Typ : Entity_Id) is
2229 -- Preanalyze and resolve the Default_Initial_Condition assertion
2230 -- expression at the end of the declarations to catch any errors.
2232 if Has_DIC (Typ) then
2233 Build_DIC_Procedure_Body (Typ);
2236 if Nkind (Context) = N_Package_Specification then
2238 -- Preanalyze and resolve the invariants of a private type
2239 -- at the end of the visible declarations to catch potential
2240 -- errors. Inherited class-wide invariants are not included
2241 -- because they have already been resolved.
2243 if Decls = Visible_Declarations (Context)
2244 and then Ekind_In (Typ, E_Limited_Private_Type,
2246 E_Record_Type_With_Private)
2247 and then Has_Own_Invariants (Typ)
2249 Build_Invariant_Procedure_Body
2251 Partial_Invariant => True);
2253 -- Preanalyze and resolve the invariants of a private type's
2254 -- full view at the end of the private declarations to catch
2255 -- potential errors.
2257 elsif Decls = Private_Declarations (Context)
2258 and then not Is_Private_Type (Typ)
2259 and then Has_Private_Declaration (Typ)
2260 and then Has_Invariants (Typ)
2262 Build_Invariant_Procedure_Body (Typ);
2265 end Build_Assertion_Bodies_For_Type;
2270 Decl_Id : Entity_Id;
2272 -- Start of processing for Build_Assertion_Bodies
2275 Decl := First (Decls);
2276 while Present (Decl) loop
2277 if Is_Declaration (Decl) then
2278 Decl_Id := Defining_Entity (Decl);
2280 if Is_Type (Decl_Id) then
2281 Build_Assertion_Bodies_For_Type (Decl_Id);
2287 end Build_Assertion_Bodies;
2289 ---------------------------
2290 -- Check_Entry_Contracts --
2291 ---------------------------
2293 procedure Check_Entry_Contracts is
2299 Ent := First_Entity (Current_Scope);
2300 while Present (Ent) loop
2302 -- This only concerns entries with pre/postconditions
2304 if Ekind (Ent) = E_Entry
2305 and then Present (Contract (Ent))
2306 and then Present (Pre_Post_Conditions (Contract (Ent)))
2308 ASN := Pre_Post_Conditions (Contract (Ent));
2310 Install_Formals (Ent);
2312 -- Pre/postconditions are rewritten as Check pragmas. Analysis
2313 -- is performed on a copy of the pragma expression, to prevent
2314 -- modifying the original expression.
2316 while Present (ASN) loop
2317 if Nkind (ASN) = N_Pragma then
2321 (First (Pragma_Argument_Associations (ASN))));
2322 Set_Parent (Exp, ASN);
2324 -- ??? why not Preanalyze_Assert_Expression
2329 ASN := Next_Pragma (ASN);
2337 end Check_Entry_Contracts;
2339 --------------------------------------
2340 -- Handle_Late_Controlled_Primitive --
2341 --------------------------------------
2343 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2344 Body_Spec : constant Node_Id := Specification (Body_Decl);
2345 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2346 Loc : constant Source_Ptr := Sloc (Body_Id);
2347 Params : constant List_Id :=
2348 Parameter_Specifications (Body_Spec);
2350 Spec_Id : Entity_Id;
2354 -- Consider only procedure bodies whose name matches one of the three
2355 -- controlled primitives.
2357 if Nkind (Body_Spec) /= N_Procedure_Specification
2358 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2364 -- A controlled primitive must have exactly one formal which is not
2365 -- an anonymous access type.
2367 elsif List_Length (Params) /= 1 then
2371 Typ := Parameter_Type (First (Params));
2373 if Nkind (Typ) = N_Access_Definition then
2379 -- The type of the formal must be derived from [Limited_]Controlled
2381 if not Is_Controlled (Entity (Typ)) then
2385 -- Check whether a specification exists for this body. We do not
2386 -- analyze the spec of the body in full, because it will be analyzed
2387 -- again when the body is properly analyzed, and we cannot create
2388 -- duplicate entries in the formals chain. We look for an explicit
2389 -- specification because the body may be an overriding operation and
2390 -- an inherited spec may be present.
2392 Spec_Id := Current_Entity (Body_Id);
2394 while Present (Spec_Id) loop
2395 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2396 and then Scope (Spec_Id) = Current_Scope
2397 and then Present (First_Formal (Spec_Id))
2398 and then No (Next_Formal (First_Formal (Spec_Id)))
2399 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2400 and then Comes_From_Source (Spec_Id)
2405 Spec_Id := Homonym (Spec_Id);
2408 -- At this point the body is known to be a late controlled primitive.
2409 -- Generate a matching spec and insert it before the body. Note the
2410 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2411 -- tree in this case.
2413 Spec := Copy_Separate_Tree (Body_Spec);
2415 -- Ensure that the subprogram declaration does not inherit the null
2416 -- indicator from the body as we now have a proper spec/body pair.
2418 Set_Null_Present (Spec, False);
2420 -- Ensure that the freeze node is inserted after the declaration of
2421 -- the primitive since its expansion will freeze the primitive.
2423 Decl := Make_Subprogram_Declaration (Loc, Specification => Spec);
2425 Insert_Before_And_Analyze (Body_Decl, Decl);
2426 end Handle_Late_Controlled_Primitive;
2428 ----------------------------------------
2429 -- Remove_Partial_Visible_Refinements --
2430 ----------------------------------------
2432 procedure Remove_Partial_Visible_Refinements (Spec_Id : Entity_Id) is
2433 State_Elmt : Elmt_Id;
2435 if Present (Abstract_States (Spec_Id)) then
2436 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2437 while Present (State_Elmt) loop
2438 Set_Has_Partial_Visible_Refinement (Node (State_Elmt), False);
2439 Next_Elmt (State_Elmt);
2443 -- For a child unit, also hide the partial state refinement from
2444 -- ancestor packages.
2446 if Is_Child_Unit (Spec_Id) then
2447 Remove_Partial_Visible_Refinements (Scope (Spec_Id));
2449 end Remove_Partial_Visible_Refinements;
2451 --------------------------------
2452 -- Remove_Visible_Refinements --
2453 --------------------------------
2455 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2456 State_Elmt : Elmt_Id;
2458 if Present (Abstract_States (Spec_Id)) then
2459 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2460 while Present (State_Elmt) loop
2461 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2462 Next_Elmt (State_Elmt);
2465 end Remove_Visible_Refinements;
2467 ---------------------
2468 -- Resolve_Aspects --
2469 ---------------------
2471 procedure Resolve_Aspects is
2475 E := First_Entity (Current_Scope);
2476 while Present (E) loop
2477 Resolve_Aspect_Expressions (E);
2480 end Resolve_Aspects;
2484 Context : Node_Id := Empty;
2485 Freeze_From : Entity_Id := Empty;
2486 Next_Decl : Node_Id;
2488 Body_Seen : Boolean := False;
2489 -- Flag set when the first body [stub] is encountered
2491 -- Start of processing for Analyze_Declarations
2494 if Restriction_Check_Required (SPARK_05) then
2495 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2499 while Present (Decl) loop
2501 -- Package spec cannot contain a package declaration in SPARK
2503 if Nkind (Decl) = N_Package_Declaration
2504 and then Nkind (Parent (L)) = N_Package_Specification
2506 Check_SPARK_05_Restriction
2507 ("package specification cannot contain a package declaration",
2511 -- Complete analysis of declaration
2514 Next_Decl := Next (Decl);
2516 if No (Freeze_From) then
2517 Freeze_From := First_Entity (Current_Scope);
2520 -- At the end of a declarative part, freeze remaining entities
2521 -- declared in it. The end of the visible declarations of package
2522 -- specification is not the end of a declarative part if private
2523 -- declarations are present. The end of a package declaration is a
2524 -- freezing point only if it a library package. A task definition or
2525 -- protected type definition is not a freeze point either. Finally,
2526 -- we do not freeze entities in generic scopes, because there is no
2527 -- code generated for them and freeze nodes will be generated for
2530 -- The end of a package instantiation is not a freeze point, but
2531 -- for now we make it one, because the generic body is inserted
2532 -- (currently) immediately after. Generic instantiations will not
2533 -- be a freeze point once delayed freezing of bodies is implemented.
2534 -- (This is needed in any case for early instantiations ???).
2536 if No (Next_Decl) then
2537 if Nkind (Parent (L)) = N_Component_List then
2540 elsif Nkind_In (Parent (L), N_Protected_Definition,
2543 Check_Entry_Contracts;
2545 elsif Nkind (Parent (L)) /= N_Package_Specification then
2546 if Nkind (Parent (L)) = N_Package_Body then
2547 Freeze_From := First_Entity (Current_Scope);
2550 -- There may have been several freezing points previously,
2551 -- for example object declarations or subprogram bodies, but
2552 -- at the end of a declarative part we check freezing from
2553 -- the beginning, even though entities may already be frozen,
2554 -- in order to perform visibility checks on delayed aspects.
2557 Freeze_All (First_Entity (Current_Scope), Decl);
2558 Freeze_From := Last_Entity (Current_Scope);
2560 -- Current scope is a package specification
2562 elsif Scope (Current_Scope) /= Standard_Standard
2563 and then not Is_Child_Unit (Current_Scope)
2564 and then No (Generic_Parent (Parent (L)))
2566 -- This is needed in all cases to catch visibility errors in
2567 -- aspect expressions, but several large user tests are now
2568 -- rejected. Pending notification we restrict this call to
2575 elsif L /= Visible_Declarations (Parent (L))
2576 or else No (Private_Declarations (Parent (L)))
2577 or else Is_Empty_List (Private_Declarations (Parent (L)))
2581 -- End of a package declaration
2583 -- In compilation mode the expansion of freeze node takes care
2584 -- of resolving expressions of all aspects in the list. In ASIS
2585 -- mode this must be done explicitly.
2588 and then Scope (Current_Scope) = Standard_Standard
2593 -- This is a freeze point because it is the end of a
2594 -- compilation unit.
2596 Freeze_All (First_Entity (Current_Scope), Decl);
2597 Freeze_From := Last_Entity (Current_Scope);
2599 -- At the end of the visible declarations the expressions in
2600 -- aspects of all entities declared so far must be resolved.
2601 -- The entities themselves might be frozen later, and the
2602 -- generated pragmas and attribute definition clauses analyzed
2603 -- in full at that point, but name resolution must take place
2605 -- In addition to being the proper semantics, this is mandatory
2606 -- within generic units, because global name capture requires
2607 -- those expressions to be analyzed, given that the generated
2608 -- pragmas do not appear in the original generic tree.
2610 elsif Serious_Errors_Detected = 0 then
2614 -- If next node is a body then freeze all types before the body.
2615 -- An exception occurs for some expander-generated bodies. If these
2616 -- are generated at places where in general language rules would not
2617 -- allow a freeze point, then we assume that the expander has
2618 -- explicitly checked that all required types are properly frozen,
2619 -- and we do not cause general freezing here. This special circuit
2620 -- is used when the encountered body is marked as having already
2623 -- In all other cases (bodies that come from source, and expander
2624 -- generated bodies that have not been analyzed yet), freeze all
2625 -- types now. Note that in the latter case, the expander must take
2626 -- care to attach the bodies at a proper place in the tree so as to
2627 -- not cause unwanted freezing at that point.
2629 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2631 -- When a controlled type is frozen, the expander generates stream
2632 -- and controlled type support routines. If the freeze is caused
2633 -- by the stand alone body of Initialize, Adjust and Finalize, the
2634 -- expander will end up using the wrong version of these routines
2635 -- as the body has not been processed yet. To remedy this, detect
2636 -- a late controlled primitive and create a proper spec for it.
2637 -- This ensures that the primitive will override its inherited
2638 -- counterpart before the freeze takes place.
2640 -- If the declaration we just processed is a body, do not attempt
2641 -- to examine Next_Decl as the late primitive idiom can only apply
2642 -- to the first encountered body.
2644 -- The spec of the late primitive is not generated in ASIS mode to
2645 -- ensure a consistent list of primitives that indicates the true
2646 -- semantic structure of the program (which is not relevant when
2647 -- generating executable code.
2649 -- ??? a cleaner approach may be possible and/or this solution
2650 -- could be extended to general-purpose late primitives, TBD.
2652 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2656 if Nkind (Next_Decl) = N_Subprogram_Body then
2657 Handle_Late_Controlled_Primitive (Next_Decl);
2663 -- The generated body of an expression function does not freeze,
2664 -- unless it is a completion, in which case only the expression
2665 -- itself freezes. THis is handled when the body itself is
2666 -- analyzed (see Freeze_Expr_Types, sem_ch6.adb).
2668 Freeze_All (Freeze_From, Decl);
2669 Freeze_From := Last_Entity (Current_Scope);
2675 -- Post-freezing actions
2678 Context := Parent (L);
2680 -- Analyze the contracts of packages and their bodies
2682 if Nkind (Context) = N_Package_Specification then
2684 -- When a package has private declarations, its contract must be
2685 -- analyzed at the end of the said declarations. This way both the
2686 -- analysis and freeze actions are properly synchronized in case
2687 -- of private type use within the contract.
2689 if L = Private_Declarations (Context) then
2690 Analyze_Package_Contract (Defining_Entity (Context));
2692 -- Otherwise the contract is analyzed at the end of the visible
2695 elsif L = Visible_Declarations (Context)
2696 and then No (Private_Declarations (Context))
2698 Analyze_Package_Contract (Defining_Entity (Context));
2701 elsif Nkind (Context) = N_Package_Body then
2702 Analyze_Package_Body_Contract (Defining_Entity (Context));
2705 -- Analyze the contracts of various constructs now due to the delayed
2706 -- visibility needs of their aspects and pragmas.
2708 Analyze_Contracts (L);
2710 if Nkind (Context) = N_Package_Body then
2712 -- Ensure that all abstract states and objects declared in the
2713 -- state space of a package body are utilized as constituents.
2715 Check_Unused_Body_States (Defining_Entity (Context));
2717 -- State refinements are visible up to the end of the package body
2718 -- declarations. Hide the state refinements from visibility to
2719 -- restore the original state conditions.
2721 Remove_Visible_Refinements (Corresponding_Spec (Context));
2722 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2724 elsif Nkind (Context) = N_Package_Declaration then
2726 -- Partial state refinements are visible up to the end of the
2727 -- package spec declarations. Hide the partial state refinements
2728 -- from visibility to restore the original state conditions.
2730 Remove_Partial_Visible_Refinements (Corresponding_Spec (Context));
2733 -- Verify that all abstract states found in any package declared in
2734 -- the input declarative list have proper refinements. The check is
2735 -- performed only when the context denotes a block, entry, package,
2736 -- protected, subprogram, or task body (SPARK RM 7.2.2(3)).
2738 Check_State_Refinements (Context);
2740 -- Create the subprogram bodies which verify the run-time semantics
2741 -- of pragmas Default_Initial_Condition and [Type_]Invariant for all
2742 -- types within the current declarative list. This ensures that all
2743 -- assertion expressions are preanalyzed and resolved at the end of
2744 -- the declarative part. Note that the resolution happens even when
2745 -- freezing does not take place.
2747 Build_Assertion_Bodies (L, Context);
2749 end Analyze_Declarations;
2751 -----------------------------------
2752 -- Analyze_Full_Type_Declaration --
2753 -----------------------------------
2755 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2756 Def : constant Node_Id := Type_Definition (N);
2757 Def_Id : constant Entity_Id := Defining_Identifier (N);
2761 Is_Remote : constant Boolean :=
2762 (Is_Remote_Types (Current_Scope)
2763 or else Is_Remote_Call_Interface (Current_Scope))
2764 and then not (In_Private_Part (Current_Scope)
2765 or else In_Package_Body (Current_Scope));
2767 procedure Check_Nonoverridable_Aspects;
2768 -- Apply the rule in RM 13.1.1(18.4/4) on iterator aspects that cannot
2769 -- be overridden, and can only be confirmed on derivation.
2771 procedure Check_Ops_From_Incomplete_Type;
2772 -- If there is a tagged incomplete partial view of the type, traverse
2773 -- the primitives of the incomplete view and change the type of any
2774 -- controlling formals and result to indicate the full view. The
2775 -- primitives will be added to the full type's primitive operations
2776 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2777 -- is called from Process_Incomplete_Dependents).
2779 ----------------------------------
2780 -- Check_Nonoverridable_Aspects --
2781 ----------------------------------
2783 procedure Check_Nonoverridable_Aspects is
2784 Prev_Aspects : constant List_Id :=
2785 Aspect_Specifications (Parent (Def_Id));
2786 Par_Type : Entity_Id;
2788 function Has_Aspect_Spec
2790 Aspect_Name : Name_Id) return Boolean;
2791 -- Check whether a list of aspect specifications includes an entry
2792 -- for a specific aspect. The list is either that of a partial or
2795 ---------------------
2796 -- Has_Aspect_Spec --
2797 ---------------------
2799 function Has_Aspect_Spec
2801 Aspect_Name : Name_Id) return Boolean
2805 Spec := First (Specs);
2806 while Present (Spec) loop
2807 if Chars (Identifier (Spec)) = Aspect_Name then
2813 end Has_Aspect_Spec;
2815 -- Start of processing for Check_Nonoverridable_Aspects
2819 -- Get parent type of derived type. Note that Prev is the entity
2820 -- in the partial declaration, but its contents are now those of
2821 -- full view, while Def_Id reflects the partial view.
2823 if Is_Private_Type (Def_Id) then
2824 Par_Type := Etype (Full_View (Def_Id));
2826 Par_Type := Etype (Def_Id);
2829 -- If there is an inherited Implicit_Dereference, verify that it is
2830 -- made explicit in the partial view.
2832 if Has_Discriminants (Base_Type (Par_Type))
2833 and then Nkind (Parent (Prev)) = N_Full_Type_Declaration
2834 and then Present (Discriminant_Specifications (Parent (Prev)))
2835 and then Present (Get_Reference_Discriminant (Par_Type))
2838 not Has_Aspect_Spec (Prev_Aspects, Name_Implicit_Dereference)
2841 ("type does not inherit implicit dereference", Prev);
2844 -- If one of the views has the aspect specified, verify that it
2845 -- is consistent with that of the parent.
2848 Par_Discr : constant Entity_Id :=
2849 Get_Reference_Discriminant (Par_Type);
2850 Cur_Discr : constant Entity_Id :=
2851 Get_Reference_Discriminant (Prev);
2853 if Corresponding_Discriminant (Cur_Discr) /= Par_Discr then
2854 Error_Msg_N ("aspect incosistent with that of parent", N);
2860 -- TBD : other nonoverridable aspects.
2861 end Check_Nonoverridable_Aspects;
2863 ------------------------------------
2864 -- Check_Ops_From_Incomplete_Type --
2865 ------------------------------------
2867 procedure Check_Ops_From_Incomplete_Type is
2874 and then Ekind (Prev) = E_Incomplete_Type
2875 and then Is_Tagged_Type (Prev)
2876 and then Is_Tagged_Type (T)
2878 Elmt := First_Elmt (Primitive_Operations (Prev));
2879 while Present (Elmt) loop
2882 Formal := First_Formal (Op);
2883 while Present (Formal) loop
2884 if Etype (Formal) = Prev then
2885 Set_Etype (Formal, T);
2888 Next_Formal (Formal);
2891 if Etype (Op) = Prev then
2898 end Check_Ops_From_Incomplete_Type;
2900 -- Start of processing for Analyze_Full_Type_Declaration
2903 Prev := Find_Type_Name (N);
2905 -- The full view, if present, now points to the current type. If there
2906 -- is an incomplete partial view, set a link to it, to simplify the
2907 -- retrieval of primitive operations of the type.
2909 -- Ada 2005 (AI-50217): If the type was previously decorated when
2910 -- imported through a LIMITED WITH clause, it appears as incomplete
2911 -- but has no full view.
2913 if Ekind (Prev) = E_Incomplete_Type
2914 and then Present (Full_View (Prev))
2916 T := Full_View (Prev);
2917 Set_Incomplete_View (N, Parent (Prev));
2922 Set_Is_Pure (T, Is_Pure (Current_Scope));
2924 -- We set the flag Is_First_Subtype here. It is needed to set the
2925 -- corresponding flag for the Implicit class-wide-type created
2926 -- during tagged types processing.
2928 Set_Is_First_Subtype (T, True);
2930 -- Only composite types other than array types are allowed to have
2935 -- For derived types, the rule will be checked once we've figured
2936 -- out the parent type.
2938 when N_Derived_Type_Definition =>
2941 -- For record types, discriminants are allowed, unless we are in
2944 when N_Record_Definition =>
2945 if Present (Discriminant_Specifications (N)) then
2946 Check_SPARK_05_Restriction
2947 ("discriminant type is not allowed",
2949 (First (Discriminant_Specifications (N))));
2953 if Present (Discriminant_Specifications (N)) then
2955 ("elementary or array type cannot have discriminants",
2957 (First (Discriminant_Specifications (N))));
2961 -- Elaborate the type definition according to kind, and generate
2962 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2963 -- already done (this happens during the reanalysis that follows a call
2964 -- to the high level optimizer).
2966 if not Analyzed (T) then
2970 when N_Access_To_Subprogram_Definition =>
2971 Access_Subprogram_Declaration (T, Def);
2973 -- If this is a remote access to subprogram, we must create the
2974 -- equivalent fat pointer type, and related subprograms.
2977 Process_Remote_AST_Declaration (N);
2980 -- Validate categorization rule against access type declaration
2981 -- usually a violation in Pure unit, Shared_Passive unit.
2983 Validate_Access_Type_Declaration (T, N);
2985 when N_Access_To_Object_Definition =>
2986 Access_Type_Declaration (T, Def);
2988 -- Validate categorization rule against access type declaration
2989 -- usually a violation in Pure unit, Shared_Passive unit.
2991 Validate_Access_Type_Declaration (T, N);
2993 -- If we are in a Remote_Call_Interface package and define a
2994 -- RACW, then calling stubs and specific stream attributes
2998 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
3000 Add_RACW_Features (Def_Id);
3003 when N_Array_Type_Definition =>
3004 Array_Type_Declaration (T, Def);
3006 when N_Derived_Type_Definition =>
3007 Derived_Type_Declaration (T, N, T /= Def_Id);
3009 when N_Enumeration_Type_Definition =>
3010 Enumeration_Type_Declaration (T, Def);
3012 when N_Floating_Point_Definition =>
3013 Floating_Point_Type_Declaration (T, Def);
3015 when N_Decimal_Fixed_Point_Definition =>
3016 Decimal_Fixed_Point_Type_Declaration (T, Def);
3018 when N_Ordinary_Fixed_Point_Definition =>
3019 Ordinary_Fixed_Point_Type_Declaration (T, Def);
3021 when N_Signed_Integer_Type_Definition =>
3022 Signed_Integer_Type_Declaration (T, Def);
3024 when N_Modular_Type_Definition =>
3025 Modular_Type_Declaration (T, Def);
3027 when N_Record_Definition =>
3028 Record_Type_Declaration (T, N, Prev);
3030 -- If declaration has a parse error, nothing to elaborate.
3036 raise Program_Error;
3040 if Etype (T) = Any_Type then
3044 -- Controlled type is not allowed in SPARK
3046 if Is_Visibly_Controlled (T) then
3047 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
3050 -- Some common processing for all types
3052 Set_Depends_On_Private (T, Has_Private_Component (T));
3053 Check_Ops_From_Incomplete_Type;
3055 -- Both the declared entity, and its anonymous base type if one was
3056 -- created, need freeze nodes allocated.
3059 B : constant Entity_Id := Base_Type (T);
3062 -- In the case where the base type differs from the first subtype, we
3063 -- pre-allocate a freeze node, and set the proper link to the first
3064 -- subtype. Freeze_Entity will use this preallocated freeze node when
3065 -- it freezes the entity.
3067 -- This does not apply if the base type is a generic type, whose
3068 -- declaration is independent of the current derived definition.
3070 if B /= T and then not Is_Generic_Type (B) then
3071 Ensure_Freeze_Node (B);
3072 Set_First_Subtype_Link (Freeze_Node (B), T);
3075 -- A type that is imported through a limited_with clause cannot
3076 -- generate any code, and thus need not be frozen. However, an access
3077 -- type with an imported designated type needs a finalization list,
3078 -- which may be referenced in some other package that has non-limited
3079 -- visibility on the designated type. Thus we must create the
3080 -- finalization list at the point the access type is frozen, to
3081 -- prevent unsatisfied references at link time.
3083 if not From_Limited_With (T) or else Is_Access_Type (T) then
3084 Set_Has_Delayed_Freeze (T);
3088 -- Case where T is the full declaration of some private type which has
3089 -- been swapped in Defining_Identifier (N).
3091 if T /= Def_Id and then Is_Private_Type (Def_Id) then
3092 Process_Full_View (N, T, Def_Id);
3094 -- Record the reference. The form of this is a little strange, since
3095 -- the full declaration has been swapped in. So the first parameter
3096 -- here represents the entity to which a reference is made which is
3097 -- the "real" entity, i.e. the one swapped in, and the second
3098 -- parameter provides the reference location.
3100 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
3101 -- since we don't want a complaint about the full type being an
3102 -- unwanted reference to the private type
3105 B : constant Boolean := Has_Pragma_Unreferenced (T);
3107 Set_Has_Pragma_Unreferenced (T, False);
3108 Generate_Reference (T, T, 'c');
3109 Set_Has_Pragma_Unreferenced (T, B);
3112 Set_Completion_Referenced (Def_Id);
3114 -- For completion of incomplete type, process incomplete dependents
3115 -- and always mark the full type as referenced (it is the incomplete
3116 -- type that we get for any real reference).
3118 elsif Ekind (Prev) = E_Incomplete_Type then
3119 Process_Incomplete_Dependents (N, T, Prev);
3120 Generate_Reference (Prev, Def_Id, 'c');
3121 Set_Completion_Referenced (Def_Id);
3123 -- If not private type or incomplete type completion, this is a real
3124 -- definition of a new entity, so record it.
3127 Generate_Definition (Def_Id);
3130 -- Propagate any pending access types whose finalization masters need to
3131 -- be fully initialized from the partial to the full view. Guard against
3132 -- an illegal full view that remains unanalyzed.
3134 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
3135 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
3138 if Chars (Scope (Def_Id)) = Name_System
3139 and then Chars (Def_Id) = Name_Address
3140 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
3142 Set_Is_Descendant_Of_Address (Def_Id);
3143 Set_Is_Descendant_Of_Address (Base_Type (Def_Id));
3144 Set_Is_Descendant_Of_Address (Prev);
3147 Set_Optimize_Alignment_Flags (Def_Id);
3148 Check_Eliminated (Def_Id);
3150 -- If the declaration is a completion and aspects are present, apply
3151 -- them to the entity for the type which is currently the partial
3152 -- view, but which is the one that will be frozen.
3154 if Has_Aspects (N) then
3156 -- In most cases the partial view is a private type, and both views
3157 -- appear in different declarative parts. In the unusual case where
3158 -- the partial view is incomplete, perform the analysis on the
3159 -- full view, to prevent freezing anomalies with the corresponding
3160 -- class-wide type, which otherwise might be frozen before the
3161 -- dispatch table is built.
3164 and then Ekind (Prev) /= E_Incomplete_Type
3166 Analyze_Aspect_Specifications (N, Prev);
3171 Analyze_Aspect_Specifications (N, Def_Id);
3175 if Is_Derived_Type (Prev)
3176 and then Def_Id /= Prev
3178 Check_Nonoverridable_Aspects;
3180 end Analyze_Full_Type_Declaration;
3182 ----------------------------------
3183 -- Analyze_Incomplete_Type_Decl --
3184 ----------------------------------
3186 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
3187 F : constant Boolean := Is_Pure (Current_Scope);
3191 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
3193 Generate_Definition (Defining_Identifier (N));
3195 -- Process an incomplete declaration. The identifier must not have been
3196 -- declared already in the scope. However, an incomplete declaration may
3197 -- appear in the private part of a package, for a private type that has
3198 -- already been declared.
3200 -- In this case, the discriminants (if any) must match
3202 T := Find_Type_Name (N);
3204 Set_Ekind (T, E_Incomplete_Type);
3205 Init_Size_Align (T);
3206 Set_Is_First_Subtype (T, True);
3209 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
3210 -- incomplete types.
3212 if Tagged_Present (N) then
3213 Set_Is_Tagged_Type (T, True);
3214 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3215 Make_Class_Wide_Type (T);
3216 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3219 Set_Stored_Constraint (T, No_Elist);
3221 if Present (Discriminant_Specifications (N)) then
3223 Process_Discriminants (N);
3227 -- If the type has discriminants, nontrivial subtypes may be declared
3228 -- before the full view of the type. The full views of those subtypes
3229 -- will be built after the full view of the type.
3231 Set_Private_Dependents (T, New_Elmt_List);
3233 end Analyze_Incomplete_Type_Decl;
3235 -----------------------------------
3236 -- Analyze_Interface_Declaration --
3237 -----------------------------------
3239 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
3240 CW : constant Entity_Id := Class_Wide_Type (T);
3243 Set_Is_Tagged_Type (T);
3244 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
3246 Set_Is_Limited_Record (T, Limited_Present (Def)
3247 or else Task_Present (Def)
3248 or else Protected_Present (Def)
3249 or else Synchronized_Present (Def));
3251 -- Type is abstract if full declaration carries keyword, or if previous
3252 -- partial view did.
3254 Set_Is_Abstract_Type (T);
3255 Set_Is_Interface (T);
3257 -- Type is a limited interface if it includes the keyword limited, task,
3258 -- protected, or synchronized.
3260 Set_Is_Limited_Interface
3261 (T, Limited_Present (Def)
3262 or else Protected_Present (Def)
3263 or else Synchronized_Present (Def)
3264 or else Task_Present (Def));
3266 Set_Interfaces (T, New_Elmt_List);
3267 Set_Direct_Primitive_Operations (T, New_Elmt_List);
3269 -- Complete the decoration of the class-wide entity if it was already
3270 -- built (i.e. during the creation of the limited view)
3272 if Present (CW) then
3273 Set_Is_Interface (CW);
3274 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
3277 -- Check runtime support for synchronized interfaces
3279 if (Is_Task_Interface (T)
3280 or else Is_Protected_Interface (T)
3281 or else Is_Synchronized_Interface (T))
3282 and then not RTE_Available (RE_Select_Specific_Data)
3284 Error_Msg_CRT ("synchronized interfaces", T);
3286 end Analyze_Interface_Declaration;
3288 -----------------------------
3289 -- Analyze_Itype_Reference --
3290 -----------------------------
3292 -- Nothing to do. This node is placed in the tree only for the benefit of
3293 -- back end processing, and has no effect on the semantic processing.
3295 procedure Analyze_Itype_Reference (N : Node_Id) is
3297 pragma Assert (Is_Itype (Itype (N)));
3299 end Analyze_Itype_Reference;
3301 --------------------------------
3302 -- Analyze_Number_Declaration --
3303 --------------------------------
3305 procedure Analyze_Number_Declaration (N : Node_Id) is
3306 E : constant Node_Id := Expression (N);
3307 Id : constant Entity_Id := Defining_Identifier (N);
3308 Index : Interp_Index;
3313 Generate_Definition (Id);
3316 -- This is an optimization of a common case of an integer literal
3318 if Nkind (E) = N_Integer_Literal then
3319 Set_Is_Static_Expression (E, True);
3320 Set_Etype (E, Universal_Integer);
3322 Set_Etype (Id, Universal_Integer);
3323 Set_Ekind (Id, E_Named_Integer);
3324 Set_Is_Frozen (Id, True);
3328 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3330 -- Process expression, replacing error by integer zero, to avoid
3331 -- cascaded errors or aborts further along in the processing
3333 -- Replace Error by integer zero, which seems least likely to cause
3337 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3338 Set_Error_Posted (E);
3343 -- Verify that the expression is static and numeric. If
3344 -- the expression is overloaded, we apply the preference
3345 -- rule that favors root numeric types.
3347 if not Is_Overloaded (E) then
3349 if Has_Dynamic_Predicate_Aspect (T) then
3351 ("subtype has dynamic predicate, "
3352 & "not allowed in number declaration", N);
3358 Get_First_Interp (E, Index, It);
3359 while Present (It.Typ) loop
3360 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3361 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3363 if T = Any_Type then
3366 elsif It.Typ = Universal_Real
3368 It.Typ = Universal_Integer
3370 -- Choose universal interpretation over any other
3377 Get_Next_Interp (Index, It);
3381 if Is_Integer_Type (T) then
3383 Set_Etype (Id, Universal_Integer);
3384 Set_Ekind (Id, E_Named_Integer);
3386 elsif Is_Real_Type (T) then
3388 -- Because the real value is converted to universal_real, this is a
3389 -- legal context for a universal fixed expression.
3391 if T = Universal_Fixed then
3393 Loc : constant Source_Ptr := Sloc (N);
3394 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3396 New_Occurrence_Of (Universal_Real, Loc),
3397 Expression => Relocate_Node (E));
3404 elsif T = Any_Fixed then
3405 Error_Msg_N ("illegal context for mixed mode operation", E);
3407 -- Expression is of the form : universal_fixed * integer. Try to
3408 -- resolve as universal_real.
3410 T := Universal_Real;
3415 Set_Etype (Id, Universal_Real);
3416 Set_Ekind (Id, E_Named_Real);
3419 Wrong_Type (E, Any_Numeric);
3423 Set_Ekind (Id, E_Constant);
3424 Set_Never_Set_In_Source (Id, True);
3425 Set_Is_True_Constant (Id, True);
3429 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3430 Set_Etype (E, Etype (Id));
3433 if not Is_OK_Static_Expression (E) then
3434 Flag_Non_Static_Expr
3435 ("non-static expression used in number declaration!", E);
3436 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3437 Set_Etype (E, Any_Type);
3440 Analyze_Dimension (N);
3441 end Analyze_Number_Declaration;
3443 --------------------------------
3444 -- Analyze_Object_Declaration --
3445 --------------------------------
3447 -- WARNING: This routine manages Ghost regions. Return statements must be
3448 -- replaced by gotos which jump to the end of the routine and restore the
3451 procedure Analyze_Object_Declaration (N : Node_Id) is
3452 Loc : constant Source_Ptr := Sloc (N);
3453 Id : constant Entity_Id := Defining_Identifier (N);
3457 E : Node_Id := Expression (N);
3458 -- E is set to Expression (N) throughout this routine. When
3459 -- Expression (N) is modified, E is changed accordingly.
3461 Prev_Entity : Entity_Id := Empty;
3463 function Count_Tasks (T : Entity_Id) return Uint;
3464 -- This function is called when a non-generic library level object of a
3465 -- task type is declared. Its function is to count the static number of
3466 -- tasks declared within the type (it is only called if Has_Task is set
3467 -- for T). As a side effect, if an array of tasks with non-static bounds
3468 -- or a variant record type is encountered, Check_Restriction is called
3469 -- indicating the count is unknown.
3471 function Delayed_Aspect_Present return Boolean;
3472 -- If the declaration has an expression that is an aggregate, and it
3473 -- has aspects that require delayed analysis, the resolution of the
3474 -- aggregate must be deferred to the freeze point of the objet. This
3475 -- special processing was created for address clauses, but it must
3476 -- also apply to Alignment. This must be done before the aspect
3477 -- specifications are analyzed because we must handle the aggregate
3478 -- before the analysis of the object declaration is complete.
3480 -- Any other relevant delayed aspects on object declarations ???
3486 function Count_Tasks (T : Entity_Id) return Uint is
3492 if Is_Task_Type (T) then
3495 elsif Is_Record_Type (T) then
3496 if Has_Discriminants (T) then
3497 Check_Restriction (Max_Tasks, N);
3502 C := First_Component (T);
3503 while Present (C) loop
3504 V := V + Count_Tasks (Etype (C));
3511 elsif Is_Array_Type (T) then
3512 X := First_Index (T);
3513 V := Count_Tasks (Component_Type (T));
3514 while Present (X) loop
3517 if not Is_OK_Static_Subtype (C) then
3518 Check_Restriction (Max_Tasks, N);
3521 V := V * (UI_Max (Uint_0,
3522 Expr_Value (Type_High_Bound (C)) -
3523 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3536 ----------------------------
3537 -- Delayed_Aspect_Present --
3538 ----------------------------
3540 function Delayed_Aspect_Present return Boolean is
3545 if Present (Aspect_Specifications (N)) then
3546 A := First (Aspect_Specifications (N));
3547 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3548 while Present (A) loop
3549 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3558 end Delayed_Aspect_Present;
3562 Mode : Ghost_Mode_Type;
3563 Mode_Set : Boolean := False;
3564 Related_Id : Entity_Id;
3566 -- Start of processing for Analyze_Object_Declaration
3569 -- There are three kinds of implicit types generated by an
3570 -- object declaration:
3572 -- 1. Those generated by the original Object Definition
3574 -- 2. Those generated by the Expression
3576 -- 3. Those used to constrain the Object Definition with the
3577 -- expression constraints when the definition is unconstrained.
3579 -- They must be generated in this order to avoid order of elaboration
3580 -- issues. Thus the first step (after entering the name) is to analyze
3581 -- the object definition.
3583 if Constant_Present (N) then
3584 Prev_Entity := Current_Entity_In_Scope (Id);
3586 if Present (Prev_Entity)
3588 -- If the homograph is an implicit subprogram, it is overridden
3589 -- by the current declaration.
3591 ((Is_Overloadable (Prev_Entity)
3592 and then Is_Inherited_Operation (Prev_Entity))
3594 -- The current object is a discriminal generated for an entry
3595 -- family index. Even though the index is a constant, in this
3596 -- particular context there is no true constant redeclaration.
3597 -- Enter_Name will handle the visibility.
3600 (Is_Discriminal (Id)
3601 and then Ekind (Discriminal_Link (Id)) =
3602 E_Entry_Index_Parameter)
3604 -- The current object is the renaming for a generic declared
3605 -- within the instance.
3608 (Ekind (Prev_Entity) = E_Package
3609 and then Nkind (Parent (Prev_Entity)) =
3610 N_Package_Renaming_Declaration
3611 and then not Comes_From_Source (Prev_Entity)
3613 Is_Generic_Instance (Renamed_Entity (Prev_Entity)))
3615 -- The entity may be a homonym of a private component of the
3616 -- enclosing protected object, for which we create a local
3617 -- renaming declaration. The declaration is legal, even if
3618 -- useless when it just captures that component.
3621 (Ekind (Scope (Current_Scope)) = E_Protected_Type
3622 and then Nkind (Parent (Prev_Entity)) =
3623 N_Object_Renaming_Declaration))
3625 Prev_Entity := Empty;
3629 if Present (Prev_Entity) then
3631 -- The object declaration is Ghost when it completes a deferred Ghost
3634 Mark_And_Set_Ghost_Completion (N, Prev_Entity, Mode);
3637 Constant_Redeclaration (Id, N, T);
3639 Generate_Reference (Prev_Entity, Id, 'c');
3640 Set_Completion_Referenced (Id);
3642 if Error_Posted (N) then
3644 -- Type mismatch or illegal redeclaration; do not analyze
3645 -- expression to avoid cascaded errors.
3647 T := Find_Type_Of_Object (Object_Definition (N), N);
3649 Set_Ekind (Id, E_Variable);
3653 -- In the normal case, enter identifier at the start to catch premature
3654 -- usage in the initialization expression.
3657 Generate_Definition (Id);
3660 Mark_Coextensions (N, Object_Definition (N));
3662 T := Find_Type_Of_Object (Object_Definition (N), N);
3664 if Nkind (Object_Definition (N)) = N_Access_Definition
3666 (Access_To_Subprogram_Definition (Object_Definition (N)))
3667 and then Protected_Present
3668 (Access_To_Subprogram_Definition (Object_Definition (N)))
3670 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3673 if Error_Posted (Id) then
3675 Set_Ekind (Id, E_Variable);
3680 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3681 -- out some static checks.
3683 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3685 -- In case of aggregates we must also take care of the correct
3686 -- initialization of nested aggregates bug this is done at the
3687 -- point of the analysis of the aggregate (see sem_aggr.adb) ???
3689 if Present (Expression (N))
3690 and then Nkind (Expression (N)) = N_Aggregate
3696 Save_Typ : constant Entity_Id := Etype (Id);
3698 Set_Etype (Id, T); -- Temp. decoration for static checks
3699 Null_Exclusion_Static_Checks (N);
3700 Set_Etype (Id, Save_Typ);
3705 -- Object is marked pure if it is in a pure scope
3707 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3709 -- If deferred constant, make sure context is appropriate. We detect
3710 -- a deferred constant as a constant declaration with no expression.
3711 -- A deferred constant can appear in a package body if its completion
3712 -- is by means of an interface pragma.
3714 if Constant_Present (N) and then No (E) then
3716 -- A deferred constant may appear in the declarative part of the
3717 -- following constructs:
3721 -- extended return statements
3724 -- subprogram bodies
3727 -- When declared inside a package spec, a deferred constant must be
3728 -- completed by a full constant declaration or pragma Import. In all
3729 -- other cases, the only proper completion is pragma Import. Extended
3730 -- return statements are flagged as invalid contexts because they do
3731 -- not have a declarative part and so cannot accommodate the pragma.
3733 if Ekind (Current_Scope) = E_Return_Statement then
3735 ("invalid context for deferred constant declaration (RM 7.4)",
3738 ("\declaration requires an initialization expression",
3740 Set_Constant_Present (N, False);
3742 -- In Ada 83, deferred constant must be of private type
3744 elsif not Is_Private_Type (T) then
3745 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3747 ("(Ada 83) deferred constant must be private type", N);
3751 -- If not a deferred constant, then the object declaration freezes
3752 -- its type, unless the object is of an anonymous type and has delayed
3753 -- aspects. In that case the type is frozen when the object itself is.
3756 Check_Fully_Declared (T, N);
3758 if Has_Delayed_Aspects (Id)
3759 and then Is_Array_Type (T)
3760 and then Is_Itype (T)
3762 Set_Has_Delayed_Freeze (T);
3764 Freeze_Before (N, T);
3768 -- If the object was created by a constrained array definition, then
3769 -- set the link in both the anonymous base type and anonymous subtype
3770 -- that are built to represent the array type to point to the object.
3772 if Nkind (Object_Definition (Declaration_Node (Id))) =
3773 N_Constrained_Array_Definition
3775 Set_Related_Array_Object (T, Id);
3776 Set_Related_Array_Object (Base_Type (T), Id);
3779 -- Special checks for protected objects not at library level
3781 if Has_Protected (T) and then not Is_Library_Level_Entity (Id) then
3782 Check_Restriction (No_Local_Protected_Objects, Id);
3784 -- Protected objects with interrupt handlers must be at library level
3786 -- Ada 2005: This test is not needed (and the corresponding clause
3787 -- in the RM is removed) because accessibility checks are sufficient
3788 -- to make handlers not at the library level illegal.
3790 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3791 -- applies to the '95 version of the language as well.
3793 if Is_Protected_Type (T)
3794 and then Has_Interrupt_Handler (T)
3795 and then Ada_Version < Ada_95
3798 ("interrupt object can only be declared at library level", Id);
3802 -- Check for violation of No_Local_Timing_Events
3804 if Has_Timing_Event (T) and then not Is_Library_Level_Entity (Id) then
3805 Check_Restriction (No_Local_Timing_Events, Id);
3808 -- The actual subtype of the object is the nominal subtype, unless
3809 -- the nominal one is unconstrained and obtained from the expression.
3813 -- These checks should be performed before the initialization expression
3814 -- is considered, so that the Object_Definition node is still the same
3815 -- as in source code.
3817 -- In SPARK, the nominal subtype is always given by a subtype mark
3818 -- and must not be unconstrained. (The only exception to this is the
3819 -- acceptance of declarations of constants of type String.)
3821 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3823 Check_SPARK_05_Restriction
3824 ("subtype mark required", Object_Definition (N));
3826 elsif Is_Array_Type (T)
3827 and then not Is_Constrained (T)
3828 and then T /= Standard_String
3830 Check_SPARK_05_Restriction
3831 ("subtype mark of constrained type expected",
3832 Object_Definition (N));
3835 -- There are no aliased objects in SPARK
3837 if Aliased_Present (N) then
3838 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3841 -- Process initialization expression if present and not in error
3843 if Present (E) and then E /= Error then
3845 -- Generate an error in case of CPP class-wide object initialization.
3846 -- Required because otherwise the expansion of the class-wide
3847 -- assignment would try to use 'size to initialize the object
3848 -- (primitive that is not available in CPP tagged types).
3850 if Is_Class_Wide_Type (Act_T)
3852 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3854 (Present (Full_View (Root_Type (Etype (Act_T))))
3856 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3859 ("predefined assignment not available for 'C'P'P tagged types",
3863 Mark_Coextensions (N, E);
3866 -- In case of errors detected in the analysis of the expression,
3867 -- decorate it with the expected type to avoid cascaded errors
3869 if No (Etype (E)) then
3873 -- If an initialization expression is present, then we set the
3874 -- Is_True_Constant flag. It will be reset if this is a variable
3875 -- and it is indeed modified.
3877 Set_Is_True_Constant (Id, True);
3879 -- If we are analyzing a constant declaration, set its completion
3880 -- flag after analyzing and resolving the expression.
3882 if Constant_Present (N) then
3883 Set_Has_Completion (Id);
3886 -- Set type and resolve (type may be overridden later on). Note:
3887 -- Ekind (Id) must still be E_Void at this point so that incorrect
3888 -- early usage within E is properly diagnosed.
3892 -- If the expression is an aggregate we must look ahead to detect
3893 -- the possible presence of an address clause, and defer resolution
3894 -- and expansion of the aggregate to the freeze point of the entity.
3896 -- This is not always legal because the aggregate may contain other
3897 -- references that need freezing, e.g. references to other entities
3898 -- with address clauses. In any case, when compiling with -gnatI the
3899 -- presence of the address clause must be ignored.
3901 if Comes_From_Source (N)
3902 and then Expander_Active
3903 and then Nkind (E) = N_Aggregate
3905 ((Present (Following_Address_Clause (N))
3906 and then not Ignore_Rep_Clauses)
3907 or else Delayed_Aspect_Present)
3915 -- No further action needed if E is a call to an inlined function
3916 -- which returns an unconstrained type and it has been expanded into
3917 -- a procedure call. In that case N has been replaced by an object
3918 -- declaration without initializing expression and it has been
3919 -- analyzed (see Expand_Inlined_Call).
3921 if Back_End_Inlining
3922 and then Expander_Active
3923 and then Nkind (E) = N_Function_Call
3924 and then Nkind (Name (E)) in N_Has_Entity
3925 and then Is_Inlined (Entity (Name (E)))
3926 and then not Is_Constrained (Etype (E))
3927 and then Analyzed (N)
3928 and then No (Expression (N))
3933 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3934 -- node (which was marked already-analyzed), we need to set the type
3935 -- to something other than Any_Access in order to keep gigi happy.
3937 if Etype (E) = Any_Access then
3941 -- If the object is an access to variable, the initialization
3942 -- expression cannot be an access to constant.
3944 if Is_Access_Type (T)
3945 and then not Is_Access_Constant (T)
3946 and then Is_Access_Type (Etype (E))
3947 and then Is_Access_Constant (Etype (E))
3950 ("access to variable cannot be initialized with an "
3951 & "access-to-constant expression", E);
3954 if not Assignment_OK (N) then
3955 Check_Initialization (T, E);
3958 Check_Unset_Reference (E);
3960 -- If this is a variable, then set current value. If this is a
3961 -- declared constant of a scalar type with a static expression,
3962 -- indicate that it is always valid.
3964 if not Constant_Present (N) then
3965 if Compile_Time_Known_Value (E) then
3966 Set_Current_Value (Id, E);
3969 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3970 Set_Is_Known_Valid (Id);
3973 -- Deal with setting of null flags
3975 if Is_Access_Type (T) then
3976 if Known_Non_Null (E) then
3977 Set_Is_Known_Non_Null (Id, True);
3978 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3979 Set_Is_Known_Null (Id, True);
3983 -- Check incorrect use of dynamically tagged expressions
3985 if Is_Tagged_Type (T) then
3986 Check_Dynamically_Tagged_Expression
3992 Apply_Scalar_Range_Check (E, T);
3993 Apply_Static_Length_Check (E, T);
3995 if Nkind (Original_Node (N)) = N_Object_Declaration
3996 and then Comes_From_Source (Original_Node (N))
3998 -- Only call test if needed
4000 and then Restriction_Check_Required (SPARK_05)
4001 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
4003 Check_SPARK_05_Restriction
4004 ("initialization expression is not appropriate", E);
4007 -- A formal parameter of a specific tagged type whose related
4008 -- subprogram is subject to pragma Extensions_Visible with value
4009 -- "False" cannot be implicitly converted to a class-wide type by
4010 -- means of an initialization expression (SPARK RM 6.1.7(3)). Do
4011 -- not consider internally generated expressions.
4013 if Is_Class_Wide_Type (T)
4014 and then Comes_From_Source (E)
4015 and then Is_EVF_Expression (E)
4018 ("formal parameter cannot be implicitly converted to "
4019 & "class-wide type when Extensions_Visible is False", E);
4023 -- If the No_Streams restriction is set, check that the type of the
4024 -- object is not, and does not contain, any subtype derived from
4025 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
4026 -- Has_Stream just for efficiency reasons. There is no point in
4027 -- spending time on a Has_Stream check if the restriction is not set.
4029 if Restriction_Check_Required (No_Streams) then
4030 if Has_Stream (T) then
4031 Check_Restriction (No_Streams, N);
4035 -- Deal with predicate check before we start to do major rewriting. It
4036 -- is OK to initialize and then check the initialized value, since the
4037 -- object goes out of scope if we get a predicate failure. Note that we
4038 -- do this in the analyzer and not the expander because the analyzer
4039 -- does some substantial rewriting in some cases.
4041 -- We need a predicate check if the type has predicates that are not
4042 -- ignored, and if either there is an initializing expression, or for
4043 -- default initialization when we have at least one case of an explicit
4044 -- default initial value and then this is not an internal declaration
4045 -- whose initialization comes later (as for an aggregate expansion).
4047 if not Suppress_Assignment_Checks (N)
4048 and then Present (Predicate_Function (T))
4049 and then not Predicates_Ignored (T)
4050 and then not No_Initialization (N)
4054 Is_Partially_Initialized_Type (T, Include_Implicit => False))
4056 -- If the type has a static predicate and the expression is known at
4057 -- compile time, see if the expression satisfies the predicate.
4060 Check_Expression_Against_Static_Predicate (E, T);
4063 -- If the type is a null record and there is no explicit initial
4064 -- expression, no predicate check applies.
4066 if No (E) and then Is_Null_Record_Type (T) then
4071 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
4075 -- Case of unconstrained type
4077 if not Is_Definite_Subtype (T) then
4079 -- In SPARK, a declaration of unconstrained type is allowed
4080 -- only for constants of type string.
4082 if Is_String_Type (T) and then not Constant_Present (N) then
4083 Check_SPARK_05_Restriction
4084 ("declaration of object of unconstrained type not allowed", N);
4087 -- Nothing to do in deferred constant case
4089 if Constant_Present (N) and then No (E) then
4092 -- Case of no initialization present
4095 if No_Initialization (N) then
4098 elsif Is_Class_Wide_Type (T) then
4100 ("initialization required in class-wide declaration ", N);
4104 ("unconstrained subtype not allowed (need initialization)",
4105 Object_Definition (N));
4107 if Is_Record_Type (T) and then Has_Discriminants (T) then
4109 ("\provide initial value or explicit discriminant values",
4110 Object_Definition (N));
4113 ("\or give default discriminant values for type&",
4114 Object_Definition (N), T);
4116 elsif Is_Array_Type (T) then
4118 ("\provide initial value or explicit array bounds",
4119 Object_Definition (N));
4123 -- Case of initialization present but in error. Set initial
4124 -- expression as absent (but do not make above complaints)
4126 elsif E = Error then
4127 Set_Expression (N, Empty);
4130 -- Case of initialization present
4133 -- Check restrictions in Ada 83
4135 if not Constant_Present (N) then
4137 -- Unconstrained variables not allowed in Ada 83 mode
4139 if Ada_Version = Ada_83
4140 and then Comes_From_Source (Object_Definition (N))
4143 ("(Ada 83) unconstrained variable not allowed",
4144 Object_Definition (N));
4148 -- Now we constrain the variable from the initializing expression
4150 -- If the expression is an aggregate, it has been expanded into
4151 -- individual assignments. Retrieve the actual type from the
4152 -- expanded construct.
4154 if Is_Array_Type (T)
4155 and then No_Initialization (N)
4156 and then Nkind (Original_Node (E)) = N_Aggregate
4160 -- In case of class-wide interface object declarations we delay
4161 -- the generation of the equivalent record type declarations until
4162 -- its expansion because there are cases in they are not required.
4164 elsif Is_Interface (T) then
4167 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
4168 -- we should prevent the generation of another Itype with the
4169 -- same name as the one already generated, or we end up with
4170 -- two identical types in GNATprove.
4172 elsif GNATprove_Mode then
4175 -- If the type is an unchecked union, no subtype can be built from
4176 -- the expression. Rewrite declaration as a renaming, which the
4177 -- back-end can handle properly. This is a rather unusual case,
4178 -- because most unchecked_union declarations have default values
4179 -- for discriminants and are thus not indefinite.
4181 elsif Is_Unchecked_Union (T) then
4182 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4183 Set_Ekind (Id, E_Constant);
4185 Set_Ekind (Id, E_Variable);
4189 Make_Object_Renaming_Declaration (Loc,
4190 Defining_Identifier => Id,
4191 Subtype_Mark => New_Occurrence_Of (T, Loc),
4194 Set_Renamed_Object (Id, E);
4195 Freeze_Before (N, T);
4200 -- Ensure that the generated subtype has a unique external name
4201 -- when the related object is public. This guarantees that the
4202 -- subtype and its bounds will not be affected by switches or
4203 -- pragmas that may offset the internal counter due to extra
4206 if Is_Public (Id) then
4209 Related_Id := Empty;
4212 Expand_Subtype_From_Expr
4215 Subtype_Indic => Object_Definition (N),
4217 Related_Id => Related_Id);
4219 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4222 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4224 if Aliased_Present (N) then
4225 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4228 Freeze_Before (N, Act_T);
4229 Freeze_Before (N, T);
4232 elsif Is_Array_Type (T)
4233 and then No_Initialization (N)
4234 and then (Nkind (Original_Node (E)) = N_Aggregate
4235 or else (Nkind (Original_Node (E)) = N_Qualified_Expression
4236 and then Nkind (Original_Node (Expression
4237 (Original_Node (E)))) = N_Aggregate))
4239 if not Is_Entity_Name (Object_Definition (N)) then
4241 Check_Compile_Time_Size (Act_T);
4243 if Aliased_Present (N) then
4244 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4248 -- When the given object definition and the aggregate are specified
4249 -- independently, and their lengths might differ do a length check.
4250 -- This cannot happen if the aggregate is of the form (others =>...)
4252 if not Is_Constrained (T) then
4255 elsif Nkind (E) = N_Raise_Constraint_Error then
4257 -- Aggregate is statically illegal. Place back in declaration
4259 Set_Expression (N, E);
4260 Set_No_Initialization (N, False);
4262 elsif T = Etype (E) then
4265 elsif Nkind (E) = N_Aggregate
4266 and then Present (Component_Associations (E))
4267 and then Present (Choice_List (First (Component_Associations (E))))
4269 Nkind (First (Choice_List (First (Component_Associations (E))))) =
4275 Apply_Length_Check (E, T);
4278 -- If the type is limited unconstrained with defaulted discriminants and
4279 -- there is no expression, then the object is constrained by the
4280 -- defaults, so it is worthwhile building the corresponding subtype.
4282 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4283 and then not Is_Constrained (T)
4284 and then Has_Discriminants (T)
4287 Act_T := Build_Default_Subtype (T, N);
4289 -- Ada 2005: A limited object may be initialized by means of an
4290 -- aggregate. If the type has default discriminants it has an
4291 -- unconstrained nominal type, Its actual subtype will be obtained
4292 -- from the aggregate, and not from the default discriminants.
4297 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4299 elsif Nkind (E) = N_Function_Call
4300 and then Constant_Present (N)
4301 and then Has_Unconstrained_Elements (Etype (E))
4303 -- The back-end has problems with constants of a discriminated type
4304 -- with defaults, if the initial value is a function call. We
4305 -- generate an intermediate temporary that will receive a reference
4306 -- to the result of the call. The initialization expression then
4307 -- becomes a dereference of that temporary.
4309 Remove_Side_Effects (E);
4311 -- If this is a constant declaration of an unconstrained type and
4312 -- the initialization is an aggregate, we can use the subtype of the
4313 -- aggregate for the declared entity because it is immutable.
4315 elsif not Is_Constrained (T)
4316 and then Has_Discriminants (T)
4317 and then Constant_Present (N)
4318 and then not Has_Unchecked_Union (T)
4319 and then Nkind (E) = N_Aggregate
4324 -- Check No_Wide_Characters restriction
4326 Check_Wide_Character_Restriction (T, Object_Definition (N));
4328 -- Indicate this is not set in source. Certainly true for constants, and
4329 -- true for variables so far (will be reset for a variable if and when
4330 -- we encounter a modification in the source).
4332 Set_Never_Set_In_Source (Id);
4334 -- Now establish the proper kind and type of the object
4336 if Constant_Present (N) then
4337 Set_Ekind (Id, E_Constant);
4338 Set_Is_True_Constant (Id);
4341 Set_Ekind (Id, E_Variable);
4343 -- A variable is set as shared passive if it appears in a shared
4344 -- passive package, and is at the outer level. This is not done for
4345 -- entities generated during expansion, because those are always
4346 -- manipulated locally.
4348 if Is_Shared_Passive (Current_Scope)
4349 and then Is_Library_Level_Entity (Id)
4350 and then Comes_From_Source (Id)
4352 Set_Is_Shared_Passive (Id);
4353 Check_Shared_Var (Id, T, N);
4356 -- Set Has_Initial_Value if initializing expression present. Note
4357 -- that if there is no initializing expression, we leave the state
4358 -- of this flag unchanged (usually it will be False, but notably in
4359 -- the case of exception choice variables, it will already be true).
4362 Set_Has_Initial_Value (Id);
4366 -- Initialize alignment and size and capture alignment setting
4368 Init_Alignment (Id);
4370 Set_Optimize_Alignment_Flags (Id);
4372 -- Deal with aliased case
4374 if Aliased_Present (N) then
4375 Set_Is_Aliased (Id);
4377 -- If the object is aliased and the type is unconstrained with
4378 -- defaulted discriminants and there is no expression, then the
4379 -- object is constrained by the defaults, so it is worthwhile
4380 -- building the corresponding subtype.
4382 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4383 -- unconstrained, then only establish an actual subtype if the
4384 -- nominal subtype is indefinite. In definite cases the object is
4385 -- unconstrained in Ada 2005.
4388 and then Is_Record_Type (T)
4389 and then not Is_Constrained (T)
4390 and then Has_Discriminants (T)
4391 and then (Ada_Version < Ada_2005
4392 or else not Is_Definite_Subtype (T))
4394 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4398 -- Now we can set the type of the object
4400 Set_Etype (Id, Act_T);
4402 -- Non-constant object is marked to be treated as volatile if type is
4403 -- volatile and we clear the Current_Value setting that may have been
4404 -- set above. Doing so for constants isn't required and might interfere
4405 -- with possible uses of the object as a static expression in contexts
4406 -- incompatible with volatility (e.g. as a case-statement alternative).
4408 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4409 Set_Treat_As_Volatile (Id);
4410 Set_Current_Value (Id, Empty);
4413 -- Deal with controlled types
4415 if Has_Controlled_Component (Etype (Id))
4416 or else Is_Controlled (Etype (Id))
4418 if not Is_Library_Level_Entity (Id) then
4419 Check_Restriction (No_Nested_Finalization, N);
4421 Validate_Controlled_Object (Id);
4425 if Has_Task (Etype (Id)) then
4426 Check_Restriction (No_Tasking, N);
4428 -- Deal with counting max tasks
4430 -- Nothing to do if inside a generic
4432 if Inside_A_Generic then
4435 -- If library level entity, then count tasks
4437 elsif Is_Library_Level_Entity (Id) then
4438 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4440 -- If not library level entity, then indicate we don't know max
4441 -- tasks and also check task hierarchy restriction and blocking
4442 -- operation (since starting a task is definitely blocking).
4445 Check_Restriction (Max_Tasks, N);
4446 Check_Restriction (No_Task_Hierarchy, N);
4447 Check_Potentially_Blocking_Operation (N);
4450 -- A rather specialized test. If we see two tasks being declared
4451 -- of the same type in the same object declaration, and the task
4452 -- has an entry with an address clause, we know that program error
4453 -- will be raised at run time since we can't have two tasks with
4454 -- entries at the same address.
4456 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4461 E := First_Entity (Etype (Id));
4462 while Present (E) loop
4463 if Ekind (E) = E_Entry
4464 and then Present (Get_Attribute_Definition_Clause
4465 (E, Attribute_Address))
4467 Error_Msg_Warn := SPARK_Mode /= On;
4469 ("more than one task with same entry address<<", N);
4470 Error_Msg_N ("\Program_Error [<<", N);
4472 Make_Raise_Program_Error (Loc,
4473 Reason => PE_Duplicated_Entry_Address));
4483 -- Some simple constant-propagation: if the expression is a constant
4484 -- string initialized with a literal, share the literal. This avoids
4488 and then Is_Entity_Name (E)
4489 and then Ekind (Entity (E)) = E_Constant
4490 and then Base_Type (Etype (E)) = Standard_String
4493 Val : constant Node_Id := Constant_Value (Entity (E));
4495 if Present (Val) and then Nkind (Val) = N_String_Literal then
4496 Rewrite (E, New_Copy (Val));
4501 -- Another optimization: if the nominal subtype is unconstrained and
4502 -- the expression is a function call that returns an unconstrained
4503 -- type, rewrite the declaration as a renaming of the result of the
4504 -- call. The exceptions below are cases where the copy is expected,
4505 -- either by the back end (Aliased case) or by the semantics, as for
4506 -- initializing controlled types or copying tags for class-wide types.
4509 and then Nkind (E) = N_Explicit_Dereference
4510 and then Nkind (Original_Node (E)) = N_Function_Call
4511 and then not Is_Library_Level_Entity (Id)
4512 and then not Is_Constrained (Underlying_Type (T))
4513 and then not Is_Aliased (Id)
4514 and then not Is_Class_Wide_Type (T)
4515 and then not Is_Controlled_Active (T)
4516 and then not Has_Controlled_Component (Base_Type (T))
4517 and then Expander_Active
4520 Make_Object_Renaming_Declaration (Loc,
4521 Defining_Identifier => Id,
4522 Access_Definition => Empty,
4523 Subtype_Mark => New_Occurrence_Of
4524 (Base_Type (Etype (Id)), Loc),
4527 Set_Renamed_Object (Id, E);
4529 -- Force generation of debugging information for the constant and for
4530 -- the renamed function call.
4532 Set_Debug_Info_Needed (Id);
4533 Set_Debug_Info_Needed (Entity (Prefix (E)));
4536 if Present (Prev_Entity)
4537 and then Is_Frozen (Prev_Entity)
4538 and then not Error_Posted (Id)
4540 Error_Msg_N ("full constant declaration appears too late", N);
4543 Check_Eliminated (Id);
4545 -- Deal with setting In_Private_Part flag if in private part
4547 if Ekind (Scope (Id)) = E_Package
4548 and then In_Private_Part (Scope (Id))
4550 Set_In_Private_Part (Id);
4554 -- Initialize the refined state of a variable here because this is a
4555 -- common destination for legal and illegal object declarations.
4557 if Ekind (Id) = E_Variable then
4558 Set_Encapsulating_State (Id, Empty);
4561 if Has_Aspects (N) then
4562 Analyze_Aspect_Specifications (N, Id);
4565 Analyze_Dimension (N);
4567 -- Verify whether the object declaration introduces an illegal hidden
4568 -- state within a package subject to a null abstract state.
4570 if Ekind (Id) = E_Variable then
4571 Check_No_Hidden_State (Id);
4575 Restore_Ghost_Mode (Mode);
4577 end Analyze_Object_Declaration;
4579 ---------------------------
4580 -- Analyze_Others_Choice --
4581 ---------------------------
4583 -- Nothing to do for the others choice node itself, the semantic analysis
4584 -- of the others choice will occur as part of the processing of the parent
4586 procedure Analyze_Others_Choice (N : Node_Id) is
4587 pragma Warnings (Off, N);
4590 end Analyze_Others_Choice;
4592 -------------------------------------------
4593 -- Analyze_Private_Extension_Declaration --
4594 -------------------------------------------
4596 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4597 Indic : constant Node_Id := Subtype_Indication (N);
4598 T : constant Entity_Id := Defining_Identifier (N);
4600 Iface_Elmt : Elmt_Id;
4601 Parent_Base : Entity_Id;
4602 Parent_Type : Entity_Id;
4605 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4607 if Is_Non_Empty_List (Interface_List (N)) then
4613 Intf := First (Interface_List (N));
4614 while Present (Intf) loop
4615 T := Find_Type_Of_Subtype_Indic (Intf);
4617 Diagnose_Interface (Intf, T);
4623 Generate_Definition (T);
4625 -- For other than Ada 2012, just enter the name in the current scope
4627 if Ada_Version < Ada_2012 then
4630 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4631 -- case of private type that completes an incomplete type.
4638 Prev := Find_Type_Name (N);
4640 pragma Assert (Prev = T
4641 or else (Ekind (Prev) = E_Incomplete_Type
4642 and then Present (Full_View (Prev))
4643 and then Full_View (Prev) = T));
4647 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4648 Parent_Base := Base_Type (Parent_Type);
4650 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4651 Set_Ekind (T, Ekind (Parent_Type));
4652 Set_Etype (T, Any_Type);
4655 elsif not Is_Tagged_Type (Parent_Type) then
4657 ("parent of type extension must be a tagged type ", Indic);
4660 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4661 Error_Msg_N ("premature derivation of incomplete type", Indic);
4664 elsif Is_Concurrent_Type (Parent_Type) then
4666 ("parent type of a private extension cannot be a synchronized "
4667 & "tagged type (RM 3.9.1 (3/1))", N);
4669 Set_Etype (T, Any_Type);
4670 Set_Ekind (T, E_Limited_Private_Type);
4671 Set_Private_Dependents (T, New_Elmt_List);
4672 Set_Error_Posted (T);
4676 -- Perhaps the parent type should be changed to the class-wide type's
4677 -- specific type in this case to prevent cascading errors ???
4679 if Is_Class_Wide_Type (Parent_Type) then
4681 ("parent of type extension must not be a class-wide type", Indic);
4685 if (not Is_Package_Or_Generic_Package (Current_Scope)
4686 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4687 or else In_Private_Part (Current_Scope)
4689 Error_Msg_N ("invalid context for private extension", N);
4692 -- Set common attributes
4694 Set_Is_Pure (T, Is_Pure (Current_Scope));
4695 Set_Scope (T, Current_Scope);
4696 Set_Ekind (T, E_Record_Type_With_Private);
4697 Init_Size_Align (T);
4698 Set_Default_SSO (T);
4700 Set_Etype (T, Parent_Base);
4701 Propagate_Concurrent_Flags (T, Parent_Base);
4703 Set_Convention (T, Convention (Parent_Type));
4704 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4705 Set_Is_First_Subtype (T);
4706 Make_Class_Wide_Type (T);
4708 if Unknown_Discriminants_Present (N) then
4709 Set_Discriminant_Constraint (T, No_Elist);
4712 Build_Derived_Record_Type (N, Parent_Type, T);
4714 -- A private extension inherits the Default_Initial_Condition pragma
4715 -- coming from any parent type within the derivation chain.
4717 if Has_DIC (Parent_Type) then
4718 Set_Has_Inherited_DIC (T);
4721 -- A private extension inherits any class-wide invariants coming from a
4722 -- parent type or an interface. Note that the invariant procedure of the
4723 -- parent type should not be inherited because the private extension may
4724 -- define invariants of its own.
4726 if Has_Inherited_Invariants (Parent_Type)
4727 or else Has_Inheritable_Invariants (Parent_Type)
4729 Set_Has_Inherited_Invariants (T);
4731 elsif Present (Interfaces (T)) then
4732 Iface_Elmt := First_Elmt (Interfaces (T));
4733 while Present (Iface_Elmt) loop
4734 Iface := Node (Iface_Elmt);
4736 if Has_Inheritable_Invariants (Iface) then
4737 Set_Has_Inherited_Invariants (T);
4741 Next_Elmt (Iface_Elmt);
4745 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4746 -- synchronized formal derived type.
4748 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4749 Set_Is_Limited_Record (T);
4751 -- Formal derived type case
4753 if Is_Generic_Type (T) then
4755 -- The parent must be a tagged limited type or a synchronized
4758 if (not Is_Tagged_Type (Parent_Type)
4759 or else not Is_Limited_Type (Parent_Type))
4761 (not Is_Interface (Parent_Type)
4762 or else not Is_Synchronized_Interface (Parent_Type))
4765 ("parent type of & must be tagged limited or synchronized",
4769 -- The progenitors (if any) must be limited or synchronized
4772 if Present (Interfaces (T)) then
4773 Iface_Elmt := First_Elmt (Interfaces (T));
4774 while Present (Iface_Elmt) loop
4775 Iface := Node (Iface_Elmt);
4777 if not Is_Limited_Interface (Iface)
4778 and then not Is_Synchronized_Interface (Iface)
4781 ("progenitor & must be limited or synchronized",
4785 Next_Elmt (Iface_Elmt);
4789 -- Regular derived extension, the parent must be a limited or
4790 -- synchronized interface.
4793 if not Is_Interface (Parent_Type)
4794 or else (not Is_Limited_Interface (Parent_Type)
4795 and then not Is_Synchronized_Interface (Parent_Type))
4798 ("parent type of & must be limited interface", N, T);
4802 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4803 -- extension with a synchronized parent must be explicitly declared
4804 -- synchronized, because the full view will be a synchronized type.
4805 -- This must be checked before the check for limited types below,
4806 -- to ensure that types declared limited are not allowed to extend
4807 -- synchronized interfaces.
4809 elsif Is_Interface (Parent_Type)
4810 and then Is_Synchronized_Interface (Parent_Type)
4811 and then not Synchronized_Present (N)
4814 ("private extension of& must be explicitly synchronized",
4817 elsif Limited_Present (N) then
4818 Set_Is_Limited_Record (T);
4820 if not Is_Limited_Type (Parent_Type)
4822 (not Is_Interface (Parent_Type)
4823 or else not Is_Limited_Interface (Parent_Type))
4825 Error_Msg_NE ("parent type& of limited extension must be limited",
4831 if Has_Aspects (N) then
4832 Analyze_Aspect_Specifications (N, T);
4834 end Analyze_Private_Extension_Declaration;
4836 ---------------------------------
4837 -- Analyze_Subtype_Declaration --
4838 ---------------------------------
4840 procedure Analyze_Subtype_Declaration
4842 Skip : Boolean := False)
4844 Id : constant Entity_Id := Defining_Identifier (N);
4845 R_Checks : Check_Result;
4849 Generate_Definition (Id);
4850 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4851 Init_Size_Align (Id);
4853 -- The following guard condition on Enter_Name is to handle cases where
4854 -- the defining identifier has already been entered into the scope but
4855 -- the declaration as a whole needs to be analyzed.
4857 -- This case in particular happens for derived enumeration types. The
4858 -- derived enumeration type is processed as an inserted enumeration type
4859 -- declaration followed by a rewritten subtype declaration. The defining
4860 -- identifier, however, is entered into the name scope very early in the
4861 -- processing of the original type declaration and therefore needs to be
4862 -- avoided here, when the created subtype declaration is analyzed. (See
4863 -- Build_Derived_Types)
4865 -- This also happens when the full view of a private type is derived
4866 -- type with constraints. In this case the entity has been introduced
4867 -- in the private declaration.
4869 -- Finally this happens in some complex cases when validity checks are
4870 -- enabled, where the same subtype declaration may be analyzed twice.
4871 -- This can happen if the subtype is created by the pre-analysis of
4872 -- an attribute tht gives the range of a loop statement, and the loop
4873 -- itself appears within an if_statement that will be rewritten during
4877 or else (Present (Etype (Id))
4878 and then (Is_Private_Type (Etype (Id))
4879 or else Is_Task_Type (Etype (Id))
4880 or else Is_Rewrite_Substitution (N)))
4884 elsif Current_Entity (Id) = Id then
4891 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4893 -- Class-wide equivalent types of records with unknown discriminants
4894 -- involve the generation of an itype which serves as the private view
4895 -- of a constrained record subtype. In such cases the base type of the
4896 -- current subtype we are processing is the private itype. Use the full
4897 -- of the private itype when decorating various attributes.
4900 and then Is_Private_Type (T)
4901 and then Present (Full_View (T))
4906 -- Inherit common attributes
4908 Set_Is_Volatile (Id, Is_Volatile (T));
4909 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4910 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4911 Set_Convention (Id, Convention (T));
4913 -- If ancestor has predicates then so does the subtype, and in addition
4914 -- we must delay the freeze to properly arrange predicate inheritance.
4916 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4917 -- in which T = ID, so the above tests and assignments do nothing???
4919 if Has_Predicates (T)
4920 or else (Present (Ancestor_Subtype (T))
4921 and then Has_Predicates (Ancestor_Subtype (T)))
4923 Set_Has_Predicates (Id);
4924 Set_Has_Delayed_Freeze (Id);
4926 -- Generated subtypes inherit the predicate function from the parent
4927 -- (no aspects to examine on the generated declaration).
4929 if not Comes_From_Source (N) then
4930 Set_Ekind (Id, Ekind (T));
4932 if Present (Predicate_Function (T)) then
4933 Set_Predicate_Function (Id, Predicate_Function (T));
4935 elsif Present (Ancestor_Subtype (T))
4936 and then Has_Predicates (Ancestor_Subtype (T))
4937 and then Present (Predicate_Function (Ancestor_Subtype (T)))
4939 Set_Predicate_Function (Id,
4940 Predicate_Function (Ancestor_Subtype (T)));
4945 -- Subtype of Boolean cannot have a constraint in SPARK
4947 if Is_Boolean_Type (T)
4948 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4950 Check_SPARK_05_Restriction
4951 ("subtype of Boolean cannot have constraint", N);
4954 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4956 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4962 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4963 One_Cstr := First (Constraints (Cstr));
4964 while Present (One_Cstr) loop
4966 -- Index or discriminant constraint in SPARK must be a
4970 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4972 Check_SPARK_05_Restriction
4973 ("subtype mark required", One_Cstr);
4975 -- String subtype must have a lower bound of 1 in SPARK.
4976 -- Note that we do not need to test for the non-static case
4977 -- here, since that was already taken care of in
4978 -- Process_Range_Expr_In_Decl.
4980 elsif Base_Type (T) = Standard_String then
4981 Get_Index_Bounds (One_Cstr, Low, High);
4983 if Is_OK_Static_Expression (Low)
4984 and then Expr_Value (Low) /= 1
4986 Check_SPARK_05_Restriction
4987 ("String subtype must have lower bound of 1", N);
4997 -- In the case where there is no constraint given in the subtype
4998 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4999 -- semantic attributes must be established here.
5001 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
5002 Set_Etype (Id, Base_Type (T));
5004 -- Subtype of unconstrained array without constraint is not allowed
5007 if Is_Array_Type (T) and then not Is_Constrained (T) then
5008 Check_SPARK_05_Restriction
5009 ("subtype of unconstrained array must have constraint", N);
5014 Set_Ekind (Id, E_Array_Subtype);
5015 Copy_Array_Subtype_Attributes (Id, T);
5017 when Decimal_Fixed_Point_Kind =>
5018 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
5019 Set_Digits_Value (Id, Digits_Value (T));
5020 Set_Delta_Value (Id, Delta_Value (T));
5021 Set_Scale_Value (Id, Scale_Value (T));
5022 Set_Small_Value (Id, Small_Value (T));
5023 Set_Scalar_Range (Id, Scalar_Range (T));
5024 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
5025 Set_Is_Constrained (Id, Is_Constrained (T));
5026 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5027 Set_RM_Size (Id, RM_Size (T));
5029 when Enumeration_Kind =>
5030 Set_Ekind (Id, E_Enumeration_Subtype);
5031 Set_First_Literal (Id, First_Literal (Base_Type (T)));
5032 Set_Scalar_Range (Id, Scalar_Range (T));
5033 Set_Is_Character_Type (Id, Is_Character_Type (T));
5034 Set_Is_Constrained (Id, Is_Constrained (T));
5035 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5036 Set_RM_Size (Id, RM_Size (T));
5037 Inherit_Predicate_Flags (Id, T);
5039 when Ordinary_Fixed_Point_Kind =>
5040 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
5041 Set_Scalar_Range (Id, Scalar_Range (T));
5042 Set_Small_Value (Id, Small_Value (T));
5043 Set_Delta_Value (Id, Delta_Value (T));
5044 Set_Is_Constrained (Id, Is_Constrained (T));
5045 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5046 Set_RM_Size (Id, RM_Size (T));
5049 Set_Ekind (Id, E_Floating_Point_Subtype);
5050 Set_Scalar_Range (Id, Scalar_Range (T));
5051 Set_Digits_Value (Id, Digits_Value (T));
5052 Set_Is_Constrained (Id, Is_Constrained (T));
5054 -- If the floating point type has dimensions, these will be
5055 -- inherited subsequently when Analyze_Dimensions is called.
5057 when Signed_Integer_Kind =>
5058 Set_Ekind (Id, E_Signed_Integer_Subtype);
5059 Set_Scalar_Range (Id, Scalar_Range (T));
5060 Set_Is_Constrained (Id, Is_Constrained (T));
5061 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5062 Set_RM_Size (Id, RM_Size (T));
5063 Inherit_Predicate_Flags (Id, T);
5065 when Modular_Integer_Kind =>
5066 Set_Ekind (Id, E_Modular_Integer_Subtype);
5067 Set_Scalar_Range (Id, Scalar_Range (T));
5068 Set_Is_Constrained (Id, Is_Constrained (T));
5069 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
5070 Set_RM_Size (Id, RM_Size (T));
5071 Inherit_Predicate_Flags (Id, T);
5073 when Class_Wide_Kind =>
5074 Set_Ekind (Id, E_Class_Wide_Subtype);
5075 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5076 Set_Cloned_Subtype (Id, T);
5077 Set_Is_Tagged_Type (Id, True);
5078 Set_Has_Unknown_Discriminants
5080 Set_No_Tagged_Streams_Pragma
5081 (Id, No_Tagged_Streams_Pragma (T));
5083 if Ekind (T) = E_Class_Wide_Subtype then
5084 Set_Equivalent_Type (Id, Equivalent_Type (T));
5087 when E_Record_Subtype
5090 Set_Ekind (Id, E_Record_Subtype);
5092 if Ekind (T) = E_Record_Subtype
5093 and then Present (Cloned_Subtype (T))
5095 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
5097 Set_Cloned_Subtype (Id, T);
5100 Set_First_Entity (Id, First_Entity (T));
5101 Set_Last_Entity (Id, Last_Entity (T));
5102 Set_Has_Discriminants (Id, Has_Discriminants (T));
5103 Set_Is_Constrained (Id, Is_Constrained (T));
5104 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5105 Set_Has_Implicit_Dereference
5106 (Id, Has_Implicit_Dereference (T));
5107 Set_Has_Unknown_Discriminants
5108 (Id, Has_Unknown_Discriminants (T));
5110 if Has_Discriminants (T) then
5111 Set_Discriminant_Constraint
5112 (Id, Discriminant_Constraint (T));
5113 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5115 elsif Has_Unknown_Discriminants (Id) then
5116 Set_Discriminant_Constraint (Id, No_Elist);
5119 if Is_Tagged_Type (T) then
5120 Set_Is_Tagged_Type (Id, True);
5121 Set_No_Tagged_Streams_Pragma
5122 (Id, No_Tagged_Streams_Pragma (T));
5123 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5124 Set_Direct_Primitive_Operations
5125 (Id, Direct_Primitive_Operations (T));
5126 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5128 if Is_Interface (T) then
5129 Set_Is_Interface (Id);
5130 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
5134 when Private_Kind =>
5135 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5136 Set_Has_Discriminants (Id, Has_Discriminants (T));
5137 Set_Is_Constrained (Id, Is_Constrained (T));
5138 Set_First_Entity (Id, First_Entity (T));
5139 Set_Last_Entity (Id, Last_Entity (T));
5140 Set_Private_Dependents (Id, New_Elmt_List);
5141 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
5142 Set_Has_Implicit_Dereference
5143 (Id, Has_Implicit_Dereference (T));
5144 Set_Has_Unknown_Discriminants
5145 (Id, Has_Unknown_Discriminants (T));
5146 Set_Known_To_Have_Preelab_Init
5147 (Id, Known_To_Have_Preelab_Init (T));
5149 if Is_Tagged_Type (T) then
5150 Set_Is_Tagged_Type (Id);
5151 Set_No_Tagged_Streams_Pragma (Id,
5152 No_Tagged_Streams_Pragma (T));
5153 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
5154 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
5155 Set_Direct_Primitive_Operations (Id,
5156 Direct_Primitive_Operations (T));
5159 -- In general the attributes of the subtype of a private type
5160 -- are the attributes of the partial view of parent. However,
5161 -- the full view may be a discriminated type, and the subtype
5162 -- must share the discriminant constraint to generate correct
5163 -- calls to initialization procedures.
5165 if Has_Discriminants (T) then
5166 Set_Discriminant_Constraint
5167 (Id, Discriminant_Constraint (T));
5168 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5170 elsif Present (Full_View (T))
5171 and then Has_Discriminants (Full_View (T))
5173 Set_Discriminant_Constraint
5174 (Id, Discriminant_Constraint (Full_View (T)));
5175 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5177 -- This would seem semantically correct, but apparently
5178 -- generates spurious errors about missing components ???
5180 -- Set_Has_Discriminants (Id);
5183 Prepare_Private_Subtype_Completion (Id, N);
5185 -- If this is the subtype of a constrained private type with
5186 -- discriminants that has got a full view and we also have
5187 -- built a completion just above, show that the completion
5188 -- is a clone of the full view to the back-end.
5190 if Has_Discriminants (T)
5191 and then not Has_Unknown_Discriminants (T)
5192 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5193 and then Present (Full_View (T))
5194 and then Present (Full_View (Id))
5196 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5200 Set_Ekind (Id, E_Access_Subtype);
5201 Set_Is_Constrained (Id, Is_Constrained (T));
5202 Set_Is_Access_Constant
5203 (Id, Is_Access_Constant (T));
5204 Set_Directly_Designated_Type
5205 (Id, Designated_Type (T));
5206 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5208 -- A Pure library_item must not contain the declaration of a
5209 -- named access type, except within a subprogram, generic
5210 -- subprogram, task unit, or protected unit, or if it has
5211 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5213 if Comes_From_Source (Id)
5214 and then In_Pure_Unit
5215 and then not In_Subprogram_Task_Protected_Unit
5216 and then not No_Pool_Assigned (Id)
5219 ("named access types not allowed in pure unit", N);
5222 when Concurrent_Kind =>
5223 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5224 Set_Corresponding_Record_Type (Id,
5225 Corresponding_Record_Type (T));
5226 Set_First_Entity (Id, First_Entity (T));
5227 Set_First_Private_Entity (Id, First_Private_Entity (T));
5228 Set_Has_Discriminants (Id, Has_Discriminants (T));
5229 Set_Is_Constrained (Id, Is_Constrained (T));
5230 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5231 Set_Last_Entity (Id, Last_Entity (T));
5233 if Is_Tagged_Type (T) then
5234 Set_No_Tagged_Streams_Pragma
5235 (Id, No_Tagged_Streams_Pragma (T));
5238 if Has_Discriminants (T) then
5239 Set_Discriminant_Constraint
5240 (Id, Discriminant_Constraint (T));
5241 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5244 when Incomplete_Kind =>
5245 if Ada_Version >= Ada_2005 then
5247 -- In Ada 2005 an incomplete type can be explicitly tagged:
5248 -- propagate indication. Note that we also have to include
5249 -- subtypes for Ada 2012 extended use of incomplete types.
5251 Set_Ekind (Id, E_Incomplete_Subtype);
5252 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5253 Set_Private_Dependents (Id, New_Elmt_List);
5255 if Is_Tagged_Type (Id) then
5256 Set_No_Tagged_Streams_Pragma
5257 (Id, No_Tagged_Streams_Pragma (T));
5258 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5261 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5262 -- incomplete type visible through a limited with clause.
5264 if From_Limited_With (T)
5265 and then Present (Non_Limited_View (T))
5267 Set_From_Limited_With (Id);
5268 Set_Non_Limited_View (Id, Non_Limited_View (T));
5270 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5271 -- to the private dependents of the original incomplete
5272 -- type for future transformation.
5275 Append_Elmt (Id, Private_Dependents (T));
5278 -- If the subtype name denotes an incomplete type an error
5279 -- was already reported by Process_Subtype.
5282 Set_Etype (Id, Any_Type);
5286 raise Program_Error;
5290 if Etype (Id) = Any_Type then
5294 -- Some common processing on all types
5296 Set_Size_Info (Id, T);
5297 Set_First_Rep_Item (Id, First_Rep_Item (T));
5299 -- If the parent type is a generic actual, so is the subtype. This may
5300 -- happen in a nested instance. Why Comes_From_Source test???
5302 if not Comes_From_Source (N) then
5303 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5306 -- If this is a subtype declaration for an actual in an instance,
5307 -- inherit static and dynamic predicates if any.
5309 -- If declaration has no aspect specifications, inherit predicate
5310 -- info as well. Unclear how to handle the case of both specified
5311 -- and inherited predicates ??? Other inherited aspects, such as
5312 -- invariants, should be OK, but the combination with later pragmas
5313 -- may also require special merging.
5315 if Has_Predicates (T)
5316 and then Present (Predicate_Function (T))
5318 ((In_Instance and then not Comes_From_Source (N))
5319 or else No (Aspect_Specifications (N)))
5321 Set_Subprograms_For_Type (Id, Subprograms_For_Type (T));
5323 if Has_Static_Predicate (T) then
5324 Set_Has_Static_Predicate (Id);
5325 Set_Static_Discrete_Predicate (Id, Static_Discrete_Predicate (T));
5329 -- Remaining processing depends on characteristics of base type
5333 Set_Is_Immediately_Visible (Id, True);
5334 Set_Depends_On_Private (Id, Has_Private_Component (T));
5335 Set_Is_Descendant_Of_Address (Id, Is_Descendant_Of_Address (T));
5337 if Is_Interface (T) then
5338 Set_Is_Interface (Id);
5341 if Present (Generic_Parent_Type (N))
5343 (Nkind (Parent (Generic_Parent_Type (N))) /=
5344 N_Formal_Type_Declaration
5345 or else Nkind (Formal_Type_Definition
5346 (Parent (Generic_Parent_Type (N)))) /=
5347 N_Formal_Private_Type_Definition)
5349 if Is_Tagged_Type (Id) then
5351 -- If this is a generic actual subtype for a synchronized type,
5352 -- the primitive operations are those of the corresponding record
5353 -- for which there is a separate subtype declaration.
5355 if Is_Concurrent_Type (Id) then
5357 elsif Is_Class_Wide_Type (Id) then
5358 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5360 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5363 elsif Scope (Etype (Id)) /= Standard_Standard then
5364 Derive_Subprograms (Generic_Parent_Type (N), Id);
5368 if Is_Private_Type (T) and then Present (Full_View (T)) then
5369 Conditional_Delay (Id, Full_View (T));
5371 -- The subtypes of components or subcomponents of protected types
5372 -- do not need freeze nodes, which would otherwise appear in the
5373 -- wrong scope (before the freeze node for the protected type). The
5374 -- proper subtypes are those of the subcomponents of the corresponding
5377 elsif Ekind (Scope (Id)) /= E_Protected_Type
5378 and then Present (Scope (Scope (Id))) -- error defense
5379 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5381 Conditional_Delay (Id, T);
5384 -- Check that Constraint_Error is raised for a scalar subtype indication
5385 -- when the lower or upper bound of a non-null range lies outside the
5386 -- range of the type mark.
5388 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5389 if Is_Scalar_Type (Etype (Id))
5390 and then Scalar_Range (Id) /=
5392 (Etype (Subtype_Mark (Subtype_Indication (N))))
5396 Etype (Subtype_Mark (Subtype_Indication (N))));
5398 -- In the array case, check compatibility for each index
5400 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5402 -- This really should be a subprogram that finds the indications
5406 Subt_Index : Node_Id := First_Index (Id);
5407 Target_Index : Node_Id :=
5409 (Subtype_Mark (Subtype_Indication (N))));
5410 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5413 while Present (Subt_Index) loop
5414 if ((Nkind (Subt_Index) = N_Identifier
5415 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5416 or else Nkind (Subt_Index) = N_Subtype_Indication)
5418 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5421 Target_Typ : constant Entity_Id :=
5422 Etype (Target_Index);
5426 (Scalar_Range (Etype (Subt_Index)),
5429 Defining_Identifier (N));
5431 -- Reset Has_Dynamic_Range_Check on the subtype to
5432 -- prevent elision of the index check due to a dynamic
5433 -- check generated for a preceding index (needed since
5434 -- Insert_Range_Checks tries to avoid generating
5435 -- redundant checks on a given declaration).
5437 Set_Has_Dynamic_Range_Check (N, False);
5443 Sloc (Defining_Identifier (N)));
5445 -- Record whether this index involved a dynamic check
5448 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5452 Next_Index (Subt_Index);
5453 Next_Index (Target_Index);
5456 -- Finally, mark whether the subtype involves dynamic checks
5458 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5463 Set_Optimize_Alignment_Flags (Id);
5464 Check_Eliminated (Id);
5467 if Has_Aspects (N) then
5468 Analyze_Aspect_Specifications (N, Id);
5471 Analyze_Dimension (N);
5473 -- Check No_Dynamic_Sized_Objects restriction, which disallows subtype
5474 -- indications on composite types where the constraints are dynamic.
5475 -- Note that object declarations and aggregates generate implicit
5476 -- subtype declarations, which this covers. One special case is that the
5477 -- implicitly generated "=" for discriminated types includes an
5478 -- offending subtype declaration, which is harmless, so we ignore it
5481 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5483 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
5485 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint
5486 and then not (Is_Internal (Id)
5487 and then Is_TSS (Scope (Id),
5488 TSS_Composite_Equality))
5489 and then not Within_Init_Proc
5490 and then not All_Composite_Constraints_Static (Cstr)
5492 Check_Restriction (No_Dynamic_Sized_Objects, Cstr);
5496 end Analyze_Subtype_Declaration;
5498 --------------------------------
5499 -- Analyze_Subtype_Indication --
5500 --------------------------------
5502 procedure Analyze_Subtype_Indication (N : Node_Id) is
5503 T : constant Entity_Id := Subtype_Mark (N);
5504 R : constant Node_Id := Range_Expression (Constraint (N));
5511 Set_Etype (N, Etype (R));
5512 Resolve (R, Entity (T));
5514 Set_Error_Posted (R);
5515 Set_Error_Posted (T);
5517 end Analyze_Subtype_Indication;
5519 --------------------------
5520 -- Analyze_Variant_Part --
5521 --------------------------
5523 procedure Analyze_Variant_Part (N : Node_Id) is
5524 Discr_Name : Node_Id;
5525 Discr_Type : Entity_Id;
5527 procedure Process_Variant (A : Node_Id);
5528 -- Analyze declarations for a single variant
5530 package Analyze_Variant_Choices is
5531 new Generic_Analyze_Choices (Process_Variant);
5532 use Analyze_Variant_Choices;
5534 ---------------------
5535 -- Process_Variant --
5536 ---------------------
5538 procedure Process_Variant (A : Node_Id) is
5539 CL : constant Node_Id := Component_List (A);
5541 if not Null_Present (CL) then
5542 Analyze_Declarations (Component_Items (CL));
5544 if Present (Variant_Part (CL)) then
5545 Analyze (Variant_Part (CL));
5548 end Process_Variant;
5550 -- Start of processing for Analyze_Variant_Part
5553 Discr_Name := Name (N);
5554 Analyze (Discr_Name);
5556 -- If Discr_Name bad, get out (prevent cascaded errors)
5558 if Etype (Discr_Name) = Any_Type then
5562 -- Check invalid discriminant in variant part
5564 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5565 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5568 Discr_Type := Etype (Entity (Discr_Name));
5570 if not Is_Discrete_Type (Discr_Type) then
5572 ("discriminant in a variant part must be of a discrete type",
5577 -- Now analyze the choices, which also analyzes the declarations that
5578 -- are associated with each choice.
5580 Analyze_Choices (Variants (N), Discr_Type);
5582 -- Note: we used to instantiate and call Check_Choices here to check
5583 -- that the choices covered the discriminant, but it's too early to do
5584 -- that because of statically predicated subtypes, whose analysis may
5585 -- be deferred to their freeze point which may be as late as the freeze
5586 -- point of the containing record. So this call is now to be found in
5587 -- Freeze_Record_Declaration.
5589 end Analyze_Variant_Part;
5591 ----------------------------
5592 -- Array_Type_Declaration --
5593 ----------------------------
5595 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5596 Component_Def : constant Node_Id := Component_Definition (Def);
5597 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5598 P : constant Node_Id := Parent (Def);
5599 Element_Type : Entity_Id;
5600 Implicit_Base : Entity_Id;
5604 Related_Id : Entity_Id := Empty;
5607 if Nkind (Def) = N_Constrained_Array_Definition then
5608 Index := First (Discrete_Subtype_Definitions (Def));
5610 Index := First (Subtype_Marks (Def));
5613 -- Find proper names for the implicit types which may be public. In case
5614 -- of anonymous arrays we use the name of the first object of that type
5618 Related_Id := Defining_Identifier (P);
5624 while Present (Index) loop
5627 -- Test for odd case of trying to index a type by the type itself
5629 if Is_Entity_Name (Index) and then Entity (Index) = T then
5630 Error_Msg_N ("type& cannot be indexed by itself", Index);
5631 Set_Entity (Index, Standard_Boolean);
5632 Set_Etype (Index, Standard_Boolean);
5635 -- Check SPARK restriction requiring a subtype mark
5637 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5638 Check_SPARK_05_Restriction ("subtype mark required", Index);
5641 -- Add a subtype declaration for each index of private array type
5642 -- declaration whose etype is also private. For example:
5645 -- type Index is private;
5647 -- type Table is array (Index) of ...
5650 -- This is currently required by the expander for the internally
5651 -- generated equality subprogram of records with variant parts in
5652 -- which the etype of some component is such private type.
5654 if Ekind (Current_Scope) = E_Package
5655 and then In_Private_Part (Current_Scope)
5656 and then Has_Private_Declaration (Etype (Index))
5659 Loc : constant Source_Ptr := Sloc (Def);
5664 New_E := Make_Temporary (Loc, 'T');
5665 Set_Is_Internal (New_E);
5668 Make_Subtype_Declaration (Loc,
5669 Defining_Identifier => New_E,
5670 Subtype_Indication =>
5671 New_Occurrence_Of (Etype (Index), Loc));
5673 Insert_Before (Parent (Def), Decl);
5675 Set_Etype (Index, New_E);
5677 -- If the index is a range the Entity attribute is not
5678 -- available. Example:
5681 -- type T is private;
5683 -- type T is new Natural;
5684 -- Table : array (T(1) .. T(10)) of Boolean;
5687 if Nkind (Index) /= N_Range then
5688 Set_Entity (Index, New_E);
5693 Make_Index (Index, P, Related_Id, Nb_Index);
5695 -- Check error of subtype with predicate for index type
5697 Bad_Predicated_Subtype_Use
5698 ("subtype& has predicate, not allowed as index subtype",
5699 Index, Etype (Index));
5701 -- Move to next index
5704 Nb_Index := Nb_Index + 1;
5707 -- Process subtype indication if one is present
5709 if Present (Component_Typ) then
5710 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5712 Set_Etype (Component_Typ, Element_Type);
5714 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5715 Check_SPARK_05_Restriction
5716 ("subtype mark required", Component_Typ);
5719 -- Ada 2005 (AI-230): Access Definition case
5721 else pragma Assert (Present (Access_Definition (Component_Def)));
5723 -- Indicate that the anonymous access type is created by the
5724 -- array type declaration.
5726 Element_Type := Access_Definition
5728 N => Access_Definition (Component_Def));
5729 Set_Is_Local_Anonymous_Access (Element_Type);
5731 -- Propagate the parent. This field is needed if we have to generate
5732 -- the master_id associated with an anonymous access to task type
5733 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5735 Set_Parent (Element_Type, Parent (T));
5737 -- Ada 2005 (AI-230): In case of components that are anonymous access
5738 -- types the level of accessibility depends on the enclosing type
5741 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5743 -- Ada 2005 (AI-254)
5746 CD : constant Node_Id :=
5747 Access_To_Subprogram_Definition
5748 (Access_Definition (Component_Def));
5750 if Present (CD) and then Protected_Present (CD) then
5752 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5757 -- Constrained array case
5760 T := Create_Itype (E_Void, P, Related_Id, 'T');
5763 if Nkind (Def) = N_Constrained_Array_Definition then
5765 -- Establish Implicit_Base as unconstrained base type
5767 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5769 Set_Etype (Implicit_Base, Implicit_Base);
5770 Set_Scope (Implicit_Base, Current_Scope);
5771 Set_Has_Delayed_Freeze (Implicit_Base);
5772 Set_Default_SSO (Implicit_Base);
5774 -- The constrained array type is a subtype of the unconstrained one
5776 Set_Ekind (T, E_Array_Subtype);
5777 Init_Size_Align (T);
5778 Set_Etype (T, Implicit_Base);
5779 Set_Scope (T, Current_Scope);
5780 Set_Is_Constrained (T);
5782 First (Discrete_Subtype_Definitions (Def)));
5783 Set_Has_Delayed_Freeze (T);
5785 -- Complete setup of implicit base type
5787 Set_Component_Size (Implicit_Base, Uint_0);
5788 Set_Component_Type (Implicit_Base, Element_Type);
5789 Set_Finalize_Storage_Only
5791 Finalize_Storage_Only (Element_Type));
5792 Set_First_Index (Implicit_Base, First_Index (T));
5793 Set_Has_Controlled_Component
5795 Has_Controlled_Component (Element_Type)
5796 or else Is_Controlled_Active (Element_Type));
5797 Set_Packed_Array_Impl_Type
5798 (Implicit_Base, Empty);
5800 Propagate_Concurrent_Flags (Implicit_Base, Element_Type);
5802 -- Unconstrained array case
5805 Set_Ekind (T, E_Array_Type);
5806 Init_Size_Align (T);
5808 Set_Scope (T, Current_Scope);
5809 Set_Component_Size (T, Uint_0);
5810 Set_Is_Constrained (T, False);
5811 Set_First_Index (T, First (Subtype_Marks (Def)));
5812 Set_Has_Delayed_Freeze (T, True);
5813 Propagate_Concurrent_Flags (T, Element_Type);
5814 Set_Has_Controlled_Component (T, Has_Controlled_Component
5817 Is_Controlled_Active (Element_Type));
5818 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5820 Set_Default_SSO (T);
5823 -- Common attributes for both cases
5825 Set_Component_Type (Base_Type (T), Element_Type);
5826 Set_Packed_Array_Impl_Type (T, Empty);
5828 if Aliased_Present (Component_Definition (Def)) then
5829 Check_SPARK_05_Restriction
5830 ("aliased is not allowed", Component_Definition (Def));
5831 Set_Has_Aliased_Components (Etype (T));
5834 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5835 -- array type to ensure that objects of this type are initialized.
5837 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5838 Set_Can_Never_Be_Null (T);
5840 if Null_Exclusion_Present (Component_Definition (Def))
5842 -- No need to check itypes because in their case this check was
5843 -- done at their point of creation
5845 and then not Is_Itype (Element_Type)
5848 ("`NOT NULL` not allowed (null already excluded)",
5849 Subtype_Indication (Component_Definition (Def)));
5853 Priv := Private_Component (Element_Type);
5855 if Present (Priv) then
5857 -- Check for circular definitions
5859 if Priv = Any_Type then
5860 Set_Component_Type (Etype (T), Any_Type);
5862 -- There is a gap in the visibility of operations on the composite
5863 -- type only if the component type is defined in a different scope.
5865 elsif Scope (Priv) = Current_Scope then
5868 elsif Is_Limited_Type (Priv) then
5869 Set_Is_Limited_Composite (Etype (T));
5870 Set_Is_Limited_Composite (T);
5872 Set_Is_Private_Composite (Etype (T));
5873 Set_Is_Private_Composite (T);
5877 -- A syntax error in the declaration itself may lead to an empty index
5878 -- list, in which case do a minimal patch.
5880 if No (First_Index (T)) then
5881 Error_Msg_N ("missing index definition in array type declaration", T);
5884 Indexes : constant List_Id :=
5885 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5887 Set_Discrete_Subtype_Definitions (Def, Indexes);
5888 Set_First_Index (T, First (Indexes));
5893 -- Create a concatenation operator for the new type. Internal array
5894 -- types created for packed entities do not need such, they are
5895 -- compatible with the user-defined type.
5897 if Number_Dimensions (T) = 1
5898 and then not Is_Packed_Array_Impl_Type (T)
5900 New_Concatenation_Op (T);
5903 -- In the case of an unconstrained array the parser has already verified
5904 -- that all the indexes are unconstrained but we still need to make sure
5905 -- that the element type is constrained.
5907 if not Is_Definite_Subtype (Element_Type) then
5909 ("unconstrained element type in array declaration",
5910 Subtype_Indication (Component_Def));
5912 elsif Is_Abstract_Type (Element_Type) then
5914 ("the type of a component cannot be abstract",
5915 Subtype_Indication (Component_Def));
5918 -- There may be an invariant declared for the component type, but
5919 -- the construction of the component invariant checking procedure
5920 -- takes place during expansion.
5921 end Array_Type_Declaration;
5923 ------------------------------------------------------
5924 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5925 ------------------------------------------------------
5927 function Replace_Anonymous_Access_To_Protected_Subprogram
5928 (N : Node_Id) return Entity_Id
5930 Loc : constant Source_Ptr := Sloc (N);
5932 Curr_Scope : constant Scope_Stack_Entry :=
5933 Scope_Stack.Table (Scope_Stack.Last);
5935 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5938 -- Access definition in declaration
5941 -- Object definition or formal definition with an access definition
5944 -- Declaration of anonymous access to subprogram type
5947 -- Original specification in access to subprogram
5952 Set_Is_Internal (Anon);
5955 when N_Constrained_Array_Definition
5956 | N_Component_Declaration
5957 | N_Unconstrained_Array_Definition
5959 Comp := Component_Definition (N);
5960 Acc := Access_Definition (Comp);
5962 when N_Discriminant_Specification =>
5963 Comp := Discriminant_Type (N);
5966 when N_Parameter_Specification =>
5967 Comp := Parameter_Type (N);
5970 when N_Access_Function_Definition =>
5971 Comp := Result_Definition (N);
5974 when N_Object_Declaration =>
5975 Comp := Object_Definition (N);
5978 when N_Function_Specification =>
5979 Comp := Result_Definition (N);
5983 raise Program_Error;
5986 Spec := Access_To_Subprogram_Definition (Acc);
5989 Make_Full_Type_Declaration (Loc,
5990 Defining_Identifier => Anon,
5991 Type_Definition => Copy_Separate_Tree (Spec));
5993 Mark_Rewrite_Insertion (Decl);
5995 -- In ASIS mode, analyze the profile on the original node, because
5996 -- the separate copy does not provide enough links to recover the
5997 -- original tree. Analysis is limited to type annotations, within
5998 -- a temporary scope that serves as an anonymous subprogram to collect
5999 -- otherwise useless temporaries and itypes.
6003 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
6006 if Nkind (Spec) = N_Access_Function_Definition then
6007 Set_Ekind (Typ, E_Function);
6009 Set_Ekind (Typ, E_Procedure);
6012 Set_Parent (Typ, N);
6013 Set_Scope (Typ, Current_Scope);
6016 -- Nothing to do if procedure is parameterless
6018 if Present (Parameter_Specifications (Spec)) then
6019 Process_Formals (Parameter_Specifications (Spec), Spec);
6022 if Nkind (Spec) = N_Access_Function_Definition then
6024 Def : constant Node_Id := Result_Definition (Spec);
6027 -- The result might itself be an anonymous access type, so
6030 if Nkind (Def) = N_Access_Definition then
6031 if Present (Access_To_Subprogram_Definition (Def)) then
6034 Replace_Anonymous_Access_To_Protected_Subprogram
6037 Find_Type (Subtype_Mark (Def));
6050 -- Insert the new declaration in the nearest enclosing scope. If the
6051 -- parent is a body and N is its return type, the declaration belongs
6052 -- in the enclosing scope. Likewise if N is the type of a parameter.
6056 if Nkind (N) = N_Function_Specification
6057 and then Nkind (P) = N_Subprogram_Body
6060 elsif Nkind (N) = N_Parameter_Specification
6061 and then Nkind (P) in N_Subprogram_Specification
6062 and then Nkind (Parent (P)) = N_Subprogram_Body
6064 P := Parent (Parent (P));
6067 while Present (P) and then not Has_Declarations (P) loop
6071 pragma Assert (Present (P));
6073 if Nkind (P) = N_Package_Specification then
6074 Prepend (Decl, Visible_Declarations (P));
6076 Prepend (Decl, Declarations (P));
6079 -- Replace the anonymous type with an occurrence of the new declaration.
6080 -- In all cases the rewritten node does not have the null-exclusion
6081 -- attribute because (if present) it was already inherited by the
6082 -- anonymous entity (Anon). Thus, in case of components we do not
6083 -- inherit this attribute.
6085 if Nkind (N) = N_Parameter_Specification then
6086 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6087 Set_Etype (Defining_Identifier (N), Anon);
6088 Set_Null_Exclusion_Present (N, False);
6090 elsif Nkind (N) = N_Object_Declaration then
6091 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6092 Set_Etype (Defining_Identifier (N), Anon);
6094 elsif Nkind (N) = N_Access_Function_Definition then
6095 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6097 elsif Nkind (N) = N_Function_Specification then
6098 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
6099 Set_Etype (Defining_Unit_Name (N), Anon);
6103 Make_Component_Definition (Loc,
6104 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
6107 Mark_Rewrite_Insertion (Comp);
6109 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition)
6110 or else (Nkind (Parent (N)) = N_Full_Type_Declaration
6111 and then not Is_Type (Current_Scope))
6114 -- Declaration can be analyzed in the current scope.
6119 -- Temporarily remove the current scope (record or subprogram) from
6120 -- the stack to add the new declarations to the enclosing scope.
6121 -- The anonymous entity is an Itype with the proper attributes.
6123 Scope_Stack.Decrement_Last;
6125 Set_Is_Itype (Anon);
6126 Set_Associated_Node_For_Itype (Anon, N);
6127 Scope_Stack.Append (Curr_Scope);
6130 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
6131 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
6133 end Replace_Anonymous_Access_To_Protected_Subprogram;
6135 -------------------------------
6136 -- Build_Derived_Access_Type --
6137 -------------------------------
6139 procedure Build_Derived_Access_Type
6141 Parent_Type : Entity_Id;
6142 Derived_Type : Entity_Id)
6144 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
6146 Desig_Type : Entity_Id;
6148 Discr_Con_Elist : Elist_Id;
6149 Discr_Con_El : Elmt_Id;
6153 -- Set the designated type so it is available in case this is an access
6154 -- to a self-referential type, e.g. a standard list type with a next
6155 -- pointer. Will be reset after subtype is built.
6157 Set_Directly_Designated_Type
6158 (Derived_Type, Designated_Type (Parent_Type));
6160 Subt := Process_Subtype (S, N);
6162 if Nkind (S) /= N_Subtype_Indication
6163 and then Subt /= Base_Type (Subt)
6165 Set_Ekind (Derived_Type, E_Access_Subtype);
6168 if Ekind (Derived_Type) = E_Access_Subtype then
6170 Pbase : constant Entity_Id := Base_Type (Parent_Type);
6171 Ibase : constant Entity_Id :=
6172 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
6173 Svg_Chars : constant Name_Id := Chars (Ibase);
6174 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
6177 Copy_Node (Pbase, Ibase);
6179 -- Restore Itype status after Copy_Node
6181 Set_Is_Itype (Ibase);
6182 Set_Associated_Node_For_Itype (Ibase, N);
6184 Set_Chars (Ibase, Svg_Chars);
6185 Set_Next_Entity (Ibase, Svg_Next_E);
6186 Set_Sloc (Ibase, Sloc (Derived_Type));
6187 Set_Scope (Ibase, Scope (Derived_Type));
6188 Set_Freeze_Node (Ibase, Empty);
6189 Set_Is_Frozen (Ibase, False);
6190 Set_Comes_From_Source (Ibase, False);
6191 Set_Is_First_Subtype (Ibase, False);
6193 Set_Etype (Ibase, Pbase);
6194 Set_Etype (Derived_Type, Ibase);
6198 Set_Directly_Designated_Type
6199 (Derived_Type, Designated_Type (Subt));
6201 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
6202 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
6203 Set_Size_Info (Derived_Type, Parent_Type);
6204 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
6205 Set_Depends_On_Private (Derived_Type,
6206 Has_Private_Component (Derived_Type));
6207 Conditional_Delay (Derived_Type, Subt);
6209 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
6210 -- that it is not redundant.
6212 if Null_Exclusion_Present (Type_Definition (N)) then
6213 Set_Can_Never_Be_Null (Derived_Type);
6215 elsif Can_Never_Be_Null (Parent_Type) then
6216 Set_Can_Never_Be_Null (Derived_Type);
6219 -- Note: we do not copy the Storage_Size_Variable, since we always go to
6220 -- the root type for this information.
6222 -- Apply range checks to discriminants for derived record case
6223 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6225 Desig_Type := Designated_Type (Derived_Type);
6227 if Is_Composite_Type (Desig_Type)
6228 and then (not Is_Array_Type (Desig_Type))
6229 and then Has_Discriminants (Desig_Type)
6230 and then Base_Type (Desig_Type) /= Desig_Type
6232 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6233 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6235 Discr := First_Discriminant (Base_Type (Desig_Type));
6236 while Present (Discr_Con_El) loop
6237 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6238 Next_Elmt (Discr_Con_El);
6239 Next_Discriminant (Discr);
6242 end Build_Derived_Access_Type;
6244 ------------------------------
6245 -- Build_Derived_Array_Type --
6246 ------------------------------
6248 procedure Build_Derived_Array_Type
6250 Parent_Type : Entity_Id;
6251 Derived_Type : Entity_Id)
6253 Loc : constant Source_Ptr := Sloc (N);
6254 Tdef : constant Node_Id := Type_Definition (N);
6255 Indic : constant Node_Id := Subtype_Indication (Tdef);
6256 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6257 Implicit_Base : Entity_Id;
6258 New_Indic : Node_Id;
6260 procedure Make_Implicit_Base;
6261 -- If the parent subtype is constrained, the derived type is a subtype
6262 -- of an implicit base type derived from the parent base.
6264 ------------------------
6265 -- Make_Implicit_Base --
6266 ------------------------
6268 procedure Make_Implicit_Base is
6271 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6273 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6274 Set_Etype (Implicit_Base, Parent_Base);
6276 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6277 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6279 Set_Has_Delayed_Freeze (Implicit_Base, True);
6280 end Make_Implicit_Base;
6282 -- Start of processing for Build_Derived_Array_Type
6285 if not Is_Constrained (Parent_Type) then
6286 if Nkind (Indic) /= N_Subtype_Indication then
6287 Set_Ekind (Derived_Type, E_Array_Type);
6289 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6290 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6292 Set_Has_Delayed_Freeze (Derived_Type, True);
6296 Set_Etype (Derived_Type, Implicit_Base);
6299 Make_Subtype_Declaration (Loc,
6300 Defining_Identifier => Derived_Type,
6301 Subtype_Indication =>
6302 Make_Subtype_Indication (Loc,
6303 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6304 Constraint => Constraint (Indic)));
6306 Rewrite (N, New_Indic);
6311 if Nkind (Indic) /= N_Subtype_Indication then
6314 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6315 Set_Etype (Derived_Type, Implicit_Base);
6316 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6319 Error_Msg_N ("illegal constraint on constrained type", Indic);
6323 -- If parent type is not a derived type itself, and is declared in
6324 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6325 -- the new type's concatenation operator since Derive_Subprograms
6326 -- will not inherit the parent's operator. If the parent type is
6327 -- unconstrained, the operator is of the unconstrained base type.
6329 if Number_Dimensions (Parent_Type) = 1
6330 and then not Is_Limited_Type (Parent_Type)
6331 and then not Is_Derived_Type (Parent_Type)
6332 and then not Is_Package_Or_Generic_Package
6333 (Scope (Base_Type (Parent_Type)))
6335 if not Is_Constrained (Parent_Type)
6336 and then Is_Constrained (Derived_Type)
6338 New_Concatenation_Op (Implicit_Base);
6340 New_Concatenation_Op (Derived_Type);
6343 end Build_Derived_Array_Type;
6345 -----------------------------------
6346 -- Build_Derived_Concurrent_Type --
6347 -----------------------------------
6349 procedure Build_Derived_Concurrent_Type
6351 Parent_Type : Entity_Id;
6352 Derived_Type : Entity_Id)
6354 Loc : constant Source_Ptr := Sloc (N);
6356 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6357 Corr_Decl : Node_Id;
6358 Corr_Decl_Needed : Boolean;
6359 -- If the derived type has fewer discriminants than its parent, the
6360 -- corresponding record is also a derived type, in order to account for
6361 -- the bound discriminants. We create a full type declaration for it in
6364 Constraint_Present : constant Boolean :=
6365 Nkind (Subtype_Indication (Type_Definition (N))) =
6366 N_Subtype_Indication;
6368 D_Constraint : Node_Id;
6369 New_Constraint : Elist_Id;
6370 Old_Disc : Entity_Id;
6371 New_Disc : Entity_Id;
6375 Set_Stored_Constraint (Derived_Type, No_Elist);
6376 Corr_Decl_Needed := False;
6379 if Present (Discriminant_Specifications (N))
6380 and then Constraint_Present
6382 Old_Disc := First_Discriminant (Parent_Type);
6383 New_Disc := First (Discriminant_Specifications (N));
6384 while Present (New_Disc) and then Present (Old_Disc) loop
6385 Next_Discriminant (Old_Disc);
6390 if Present (Old_Disc) and then Expander_Active then
6392 -- The new type has fewer discriminants, so we need to create a new
6393 -- corresponding record, which is derived from the corresponding
6394 -- record of the parent, and has a stored constraint that captures
6395 -- the values of the discriminant constraints. The corresponding
6396 -- record is needed only if expander is active and code generation is
6399 -- The type declaration for the derived corresponding record has the
6400 -- same discriminant part and constraints as the current declaration.
6401 -- Copy the unanalyzed tree to build declaration.
6403 Corr_Decl_Needed := True;
6404 New_N := Copy_Separate_Tree (N);
6407 Make_Full_Type_Declaration (Loc,
6408 Defining_Identifier => Corr_Record,
6409 Discriminant_Specifications =>
6410 Discriminant_Specifications (New_N),
6412 Make_Derived_Type_Definition (Loc,
6413 Subtype_Indication =>
6414 Make_Subtype_Indication (Loc,
6417 (Corresponding_Record_Type (Parent_Type), Loc),
6420 (Subtype_Indication (Type_Definition (New_N))))));
6423 -- Copy Storage_Size and Relative_Deadline variables if task case
6425 if Is_Task_Type (Parent_Type) then
6426 Set_Storage_Size_Variable (Derived_Type,
6427 Storage_Size_Variable (Parent_Type));
6428 Set_Relative_Deadline_Variable (Derived_Type,
6429 Relative_Deadline_Variable (Parent_Type));
6432 if Present (Discriminant_Specifications (N)) then
6433 Push_Scope (Derived_Type);
6434 Check_Or_Process_Discriminants (N, Derived_Type);
6436 if Constraint_Present then
6438 Expand_To_Stored_Constraint
6440 Build_Discriminant_Constraints
6442 Subtype_Indication (Type_Definition (N)), True));
6447 elsif Constraint_Present then
6449 -- Build constrained subtype, copying the constraint, and derive
6450 -- from it to create a derived constrained type.
6453 Loc : constant Source_Ptr := Sloc (N);
6454 Anon : constant Entity_Id :=
6455 Make_Defining_Identifier (Loc,
6456 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6461 Make_Subtype_Declaration (Loc,
6462 Defining_Identifier => Anon,
6463 Subtype_Indication =>
6464 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6465 Insert_Before (N, Decl);
6468 Rewrite (Subtype_Indication (Type_Definition (N)),
6469 New_Occurrence_Of (Anon, Loc));
6470 Set_Analyzed (Derived_Type, False);
6476 -- By default, operations and private data are inherited from parent.
6477 -- However, in the presence of bound discriminants, a new corresponding
6478 -- record will be created, see below.
6480 Set_Has_Discriminants
6481 (Derived_Type, Has_Discriminants (Parent_Type));
6482 Set_Corresponding_Record_Type
6483 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6485 -- Is_Constrained is set according the parent subtype, but is set to
6486 -- False if the derived type is declared with new discriminants.
6490 (Is_Constrained (Parent_Type) or else Constraint_Present)
6491 and then not Present (Discriminant_Specifications (N)));
6493 if Constraint_Present then
6494 if not Has_Discriminants (Parent_Type) then
6495 Error_Msg_N ("untagged parent must have discriminants", N);
6497 elsif Present (Discriminant_Specifications (N)) then
6499 -- Verify that new discriminants are used to constrain old ones
6504 (Constraint (Subtype_Indication (Type_Definition (N)))));
6506 Old_Disc := First_Discriminant (Parent_Type);
6508 while Present (D_Constraint) loop
6509 if Nkind (D_Constraint) /= N_Discriminant_Association then
6511 -- Positional constraint. If it is a reference to a new
6512 -- discriminant, it constrains the corresponding old one.
6514 if Nkind (D_Constraint) = N_Identifier then
6515 New_Disc := First_Discriminant (Derived_Type);
6516 while Present (New_Disc) loop
6517 exit when Chars (New_Disc) = Chars (D_Constraint);
6518 Next_Discriminant (New_Disc);
6521 if Present (New_Disc) then
6522 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6526 Next_Discriminant (Old_Disc);
6528 -- if this is a named constraint, search by name for the old
6529 -- discriminants constrained by the new one.
6531 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6533 -- Find new discriminant with that name
6535 New_Disc := First_Discriminant (Derived_Type);
6536 while Present (New_Disc) loop
6538 Chars (New_Disc) = Chars (Expression (D_Constraint));
6539 Next_Discriminant (New_Disc);
6542 if Present (New_Disc) then
6544 -- Verify that new discriminant renames some discriminant
6545 -- of the parent type, and associate the new discriminant
6546 -- with one or more old ones that it renames.
6552 Selector := First (Selector_Names (D_Constraint));
6553 while Present (Selector) loop
6554 Old_Disc := First_Discriminant (Parent_Type);
6555 while Present (Old_Disc) loop
6556 exit when Chars (Old_Disc) = Chars (Selector);
6557 Next_Discriminant (Old_Disc);
6560 if Present (Old_Disc) then
6561 Set_Corresponding_Discriminant
6562 (New_Disc, Old_Disc);
6571 Next (D_Constraint);
6574 New_Disc := First_Discriminant (Derived_Type);
6575 while Present (New_Disc) loop
6576 if No (Corresponding_Discriminant (New_Disc)) then
6578 ("new discriminant& must constrain old one", N, New_Disc);
6581 Subtypes_Statically_Compatible
6583 Etype (Corresponding_Discriminant (New_Disc)))
6586 ("& not statically compatible with parent discriminant",
6590 Next_Discriminant (New_Disc);
6594 elsif Present (Discriminant_Specifications (N)) then
6596 ("missing discriminant constraint in untagged derivation", N);
6599 -- The entity chain of the derived type includes the new discriminants
6600 -- but shares operations with the parent.
6602 if Present (Discriminant_Specifications (N)) then
6603 Old_Disc := First_Discriminant (Parent_Type);
6604 while Present (Old_Disc) loop
6605 if No (Next_Entity (Old_Disc))
6606 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6609 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6613 Next_Discriminant (Old_Disc);
6617 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6618 if Has_Discriminants (Parent_Type) then
6619 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6620 Set_Discriminant_Constraint (
6621 Derived_Type, Discriminant_Constraint (Parent_Type));
6625 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6627 Set_Has_Completion (Derived_Type);
6629 if Corr_Decl_Needed then
6630 Set_Stored_Constraint (Derived_Type, New_Constraint);
6631 Insert_After (N, Corr_Decl);
6632 Analyze (Corr_Decl);
6633 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6635 end Build_Derived_Concurrent_Type;
6637 ------------------------------------
6638 -- Build_Derived_Enumeration_Type --
6639 ------------------------------------
6641 procedure Build_Derived_Enumeration_Type
6643 Parent_Type : Entity_Id;
6644 Derived_Type : Entity_Id)
6646 Loc : constant Source_Ptr := Sloc (N);
6647 Def : constant Node_Id := Type_Definition (N);
6648 Indic : constant Node_Id := Subtype_Indication (Def);
6649 Implicit_Base : Entity_Id;
6650 Literal : Entity_Id;
6651 New_Lit : Entity_Id;
6652 Literals_List : List_Id;
6653 Type_Decl : Node_Id;
6655 Rang_Expr : Node_Id;
6658 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6659 -- not have explicit literals lists we need to process types derived
6660 -- from them specially. This is handled by Derived_Standard_Character.
6661 -- If the parent type is a generic type, there are no literals either,
6662 -- and we construct the same skeletal representation as for the generic
6665 if Is_Standard_Character_Type (Parent_Type) then
6666 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6668 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6674 if Nkind (Indic) /= N_Subtype_Indication then
6676 Make_Attribute_Reference (Loc,
6677 Attribute_Name => Name_First,
6678 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6679 Set_Etype (Lo, Derived_Type);
6682 Make_Attribute_Reference (Loc,
6683 Attribute_Name => Name_Last,
6684 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6685 Set_Etype (Hi, Derived_Type);
6687 Set_Scalar_Range (Derived_Type,
6693 -- Analyze subtype indication and verify compatibility
6694 -- with parent type.
6696 if Base_Type (Process_Subtype (Indic, N)) /=
6697 Base_Type (Parent_Type)
6700 ("illegal constraint for formal discrete type", N);
6706 -- If a constraint is present, analyze the bounds to catch
6707 -- premature usage of the derived literals.
6709 if Nkind (Indic) = N_Subtype_Indication
6710 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6712 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6713 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6716 -- Introduce an implicit base type for the derived type even if there
6717 -- is no constraint attached to it, since this seems closer to the
6718 -- Ada semantics. Build a full type declaration tree for the derived
6719 -- type using the implicit base type as the defining identifier. The
6720 -- build a subtype declaration tree which applies the constraint (if
6721 -- any) have it replace the derived type declaration.
6723 Literal := First_Literal (Parent_Type);
6724 Literals_List := New_List;
6725 while Present (Literal)
6726 and then Ekind (Literal) = E_Enumeration_Literal
6728 -- Literals of the derived type have the same representation as
6729 -- those of the parent type, but this representation can be
6730 -- overridden by an explicit representation clause. Indicate
6731 -- that there is no explicit representation given yet. These
6732 -- derived literals are implicit operations of the new type,
6733 -- and can be overridden by explicit ones.
6735 if Nkind (Literal) = N_Defining_Character_Literal then
6737 Make_Defining_Character_Literal (Loc, Chars (Literal));
6739 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6742 Set_Ekind (New_Lit, E_Enumeration_Literal);
6743 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6744 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6745 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6746 Set_Alias (New_Lit, Literal);
6747 Set_Is_Known_Valid (New_Lit, True);
6749 Append (New_Lit, Literals_List);
6750 Next_Literal (Literal);
6754 Make_Defining_Identifier (Sloc (Derived_Type),
6755 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6757 -- Indicate the proper nature of the derived type. This must be done
6758 -- before analysis of the literals, to recognize cases when a literal
6759 -- may be hidden by a previous explicit function definition (cf.
6762 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6763 Set_Etype (Derived_Type, Implicit_Base);
6766 Make_Full_Type_Declaration (Loc,
6767 Defining_Identifier => Implicit_Base,
6768 Discriminant_Specifications => No_List,
6770 Make_Enumeration_Type_Definition (Loc, Literals_List));
6772 Mark_Rewrite_Insertion (Type_Decl);
6773 Insert_Before (N, Type_Decl);
6774 Analyze (Type_Decl);
6776 -- The anonymous base now has a full declaration, but this base
6777 -- is not a first subtype.
6779 Set_Is_First_Subtype (Implicit_Base, False);
6781 -- After the implicit base is analyzed its Etype needs to be changed
6782 -- to reflect the fact that it is derived from the parent type which
6783 -- was ignored during analysis. We also set the size at this point.
6785 Set_Etype (Implicit_Base, Parent_Type);
6787 Set_Size_Info (Implicit_Base, Parent_Type);
6788 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6789 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6791 -- Copy other flags from parent type
6793 Set_Has_Non_Standard_Rep
6794 (Implicit_Base, Has_Non_Standard_Rep
6796 Set_Has_Pragma_Ordered
6797 (Implicit_Base, Has_Pragma_Ordered
6799 Set_Has_Delayed_Freeze (Implicit_Base);
6801 -- Process the subtype indication including a validation check on the
6802 -- constraint, if any. If a constraint is given, its bounds must be
6803 -- implicitly converted to the new type.
6805 if Nkind (Indic) = N_Subtype_Indication then
6807 R : constant Node_Id :=
6808 Range_Expression (Constraint (Indic));
6811 if Nkind (R) = N_Range then
6812 Hi := Build_Scalar_Bound
6813 (High_Bound (R), Parent_Type, Implicit_Base);
6814 Lo := Build_Scalar_Bound
6815 (Low_Bound (R), Parent_Type, Implicit_Base);
6818 -- Constraint is a Range attribute. Replace with explicit
6819 -- mention of the bounds of the prefix, which must be a
6822 Analyze (Prefix (R));
6824 Convert_To (Implicit_Base,
6825 Make_Attribute_Reference (Loc,
6826 Attribute_Name => Name_Last,
6828 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6831 Convert_To (Implicit_Base,
6832 Make_Attribute_Reference (Loc,
6833 Attribute_Name => Name_First,
6835 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6842 (Type_High_Bound (Parent_Type),
6843 Parent_Type, Implicit_Base);
6846 (Type_Low_Bound (Parent_Type),
6847 Parent_Type, Implicit_Base);
6855 -- If we constructed a default range for the case where no range
6856 -- was given, then the expressions in the range must not freeze
6857 -- since they do not correspond to expressions in the source.
6858 -- However, if the type inherits predicates the expressions will
6859 -- be elaborated earlier and must freeze.
6861 if Nkind (Indic) /= N_Subtype_Indication
6862 and then not Has_Predicates (Derived_Type)
6864 Set_Must_Not_Freeze (Lo);
6865 Set_Must_Not_Freeze (Hi);
6866 Set_Must_Not_Freeze (Rang_Expr);
6870 Make_Subtype_Declaration (Loc,
6871 Defining_Identifier => Derived_Type,
6872 Subtype_Indication =>
6873 Make_Subtype_Indication (Loc,
6874 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6876 Make_Range_Constraint (Loc,
6877 Range_Expression => Rang_Expr))));
6881 -- Propagate the aspects from the original type declaration to the
6882 -- declaration of the implicit base.
6884 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6886 -- Apply a range check. Since this range expression doesn't have an
6887 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6890 if Nkind (Indic) = N_Subtype_Indication then
6892 (Range_Expression (Constraint (Indic)), Parent_Type,
6893 Source_Typ => Entity (Subtype_Mark (Indic)));
6896 end Build_Derived_Enumeration_Type;
6898 --------------------------------
6899 -- Build_Derived_Numeric_Type --
6900 --------------------------------
6902 procedure Build_Derived_Numeric_Type
6904 Parent_Type : Entity_Id;
6905 Derived_Type : Entity_Id)
6907 Loc : constant Source_Ptr := Sloc (N);
6908 Tdef : constant Node_Id := Type_Definition (N);
6909 Indic : constant Node_Id := Subtype_Indication (Tdef);
6910 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6911 No_Constraint : constant Boolean := Nkind (Indic) /=
6912 N_Subtype_Indication;
6913 Implicit_Base : Entity_Id;
6919 -- Process the subtype indication including a validation check on
6920 -- the constraint if any.
6922 Discard_Node (Process_Subtype (Indic, N));
6924 -- Introduce an implicit base type for the derived type even if there
6925 -- is no constraint attached to it, since this seems closer to the Ada
6929 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6931 Set_Etype (Implicit_Base, Parent_Base);
6932 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6933 Set_Size_Info (Implicit_Base, Parent_Base);
6934 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6935 Set_Parent (Implicit_Base, Parent (Derived_Type));
6936 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6938 -- Set RM Size for discrete type or decimal fixed-point type
6939 -- Ordinary fixed-point is excluded, why???
6941 if Is_Discrete_Type (Parent_Base)
6942 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6944 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6947 Set_Has_Delayed_Freeze (Implicit_Base);
6949 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6950 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6952 Set_Scalar_Range (Implicit_Base,
6957 if Has_Infinities (Parent_Base) then
6958 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6961 -- The Derived_Type, which is the entity of the declaration, is a
6962 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6963 -- absence of an explicit constraint.
6965 Set_Etype (Derived_Type, Implicit_Base);
6967 -- If we did not have a constraint, then the Ekind is set from the
6968 -- parent type (otherwise Process_Subtype has set the bounds)
6970 if No_Constraint then
6971 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6974 -- If we did not have a range constraint, then set the range from the
6975 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6977 if No_Constraint or else not Has_Range_Constraint (Indic) then
6978 Set_Scalar_Range (Derived_Type,
6980 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6981 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6982 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6984 if Has_Infinities (Parent_Type) then
6985 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6988 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6991 Set_Is_Descendant_Of_Address (Derived_Type,
6992 Is_Descendant_Of_Address (Parent_Type));
6993 Set_Is_Descendant_Of_Address (Implicit_Base,
6994 Is_Descendant_Of_Address (Parent_Type));
6996 -- Set remaining type-specific fields, depending on numeric type
6998 if Is_Modular_Integer_Type (Parent_Type) then
6999 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
7001 Set_Non_Binary_Modulus
7002 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
7005 (Implicit_Base, Is_Known_Valid (Parent_Base));
7007 elsif Is_Floating_Point_Type (Parent_Type) then
7009 -- Digits of base type is always copied from the digits value of
7010 -- the parent base type, but the digits of the derived type will
7011 -- already have been set if there was a constraint present.
7013 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7014 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
7016 if No_Constraint then
7017 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
7020 elsif Is_Fixed_Point_Type (Parent_Type) then
7022 -- Small of base type and derived type are always copied from the
7023 -- parent base type, since smalls never change. The delta of the
7024 -- base type is also copied from the parent base type. However the
7025 -- delta of the derived type will have been set already if a
7026 -- constraint was present.
7028 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
7029 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
7030 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
7032 if No_Constraint then
7033 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
7036 -- The scale and machine radix in the decimal case are always
7037 -- copied from the parent base type.
7039 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
7040 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
7041 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
7043 Set_Machine_Radix_10
7044 (Derived_Type, Machine_Radix_10 (Parent_Base));
7045 Set_Machine_Radix_10
7046 (Implicit_Base, Machine_Radix_10 (Parent_Base));
7048 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
7050 if No_Constraint then
7051 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
7054 -- the analysis of the subtype_indication sets the
7055 -- digits value of the derived type.
7062 if Is_Integer_Type (Parent_Type) then
7063 Set_Has_Shift_Operator
7064 (Implicit_Base, Has_Shift_Operator (Parent_Type));
7067 -- The type of the bounds is that of the parent type, and they
7068 -- must be converted to the derived type.
7070 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
7072 -- The implicit_base should be frozen when the derived type is frozen,
7073 -- but note that it is used in the conversions of the bounds. For fixed
7074 -- types we delay the determination of the bounds until the proper
7075 -- freezing point. For other numeric types this is rejected by GCC, for
7076 -- reasons that are currently unclear (???), so we choose to freeze the
7077 -- implicit base now. In the case of integers and floating point types
7078 -- this is harmless because subsequent representation clauses cannot
7079 -- affect anything, but it is still baffling that we cannot use the
7080 -- same mechanism for all derived numeric types.
7082 -- There is a further complication: actually some representation
7083 -- clauses can affect the implicit base type. For example, attribute
7084 -- definition clauses for stream-oriented attributes need to set the
7085 -- corresponding TSS entries on the base type, and this normally
7086 -- cannot be done after the base type is frozen, so the circuitry in
7087 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
7088 -- and not use Set_TSS in this case.
7090 -- There are also consequences for the case of delayed representation
7091 -- aspects for some cases. For example, a Size aspect is delayed and
7092 -- should not be evaluated to the freeze point. This early freezing
7093 -- means that the size attribute evaluation happens too early???
7095 if Is_Fixed_Point_Type (Parent_Type) then
7096 Conditional_Delay (Implicit_Base, Parent_Type);
7098 Freeze_Before (N, Implicit_Base);
7100 end Build_Derived_Numeric_Type;
7102 --------------------------------
7103 -- Build_Derived_Private_Type --
7104 --------------------------------
7106 procedure Build_Derived_Private_Type
7108 Parent_Type : Entity_Id;
7109 Derived_Type : Entity_Id;
7110 Is_Completion : Boolean;
7111 Derive_Subps : Boolean := True)
7113 Loc : constant Source_Ptr := Sloc (N);
7114 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
7115 Par_Scope : constant Entity_Id := Scope (Par_Base);
7116 Full_N : constant Node_Id := New_Copy_Tree (N);
7117 Full_Der : Entity_Id := New_Copy (Derived_Type);
7120 procedure Build_Full_Derivation;
7121 -- Build full derivation, i.e. derive from the full view
7123 procedure Copy_And_Build;
7124 -- Copy derived type declaration, replace parent with its full view,
7125 -- and build derivation
7127 ---------------------------
7128 -- Build_Full_Derivation --
7129 ---------------------------
7131 procedure Build_Full_Derivation is
7133 -- If parent scope is not open, install the declarations
7135 if not In_Open_Scopes (Par_Scope) then
7136 Install_Private_Declarations (Par_Scope);
7137 Install_Visible_Declarations (Par_Scope);
7139 Uninstall_Declarations (Par_Scope);
7141 -- If parent scope is open and in another unit, and parent has a
7142 -- completion, then the derivation is taking place in the visible
7143 -- part of a child unit. In that case retrieve the full view of
7144 -- the parent momentarily.
7146 elsif not In_Same_Source_Unit (N, Parent_Type) then
7147 Full_P := Full_View (Parent_Type);
7148 Exchange_Declarations (Parent_Type);
7150 Exchange_Declarations (Full_P);
7152 -- Otherwise it is a local derivation
7157 end Build_Full_Derivation;
7159 --------------------
7160 -- Copy_And_Build --
7161 --------------------
7163 procedure Copy_And_Build is
7164 Full_Parent : Entity_Id := Parent_Type;
7167 -- If the parent is itself derived from another private type,
7168 -- installing the private declarations has not affected its
7169 -- privacy status, so use its own full view explicitly.
7171 if Is_Private_Type (Full_Parent)
7172 and then Present (Full_View (Full_Parent))
7174 Full_Parent := Full_View (Full_Parent);
7177 -- And its underlying full view if necessary
7179 if Is_Private_Type (Full_Parent)
7180 and then Present (Underlying_Full_View (Full_Parent))
7182 Full_Parent := Underlying_Full_View (Full_Parent);
7185 -- For record, access and most enumeration types, derivation from
7186 -- the full view requires a fully-fledged declaration. In the other
7187 -- cases, just use an itype.
7189 if Ekind (Full_Parent) in Record_Kind
7190 or else Ekind (Full_Parent) in Access_Kind
7192 (Ekind (Full_Parent) in Enumeration_Kind
7193 and then not Is_Standard_Character_Type (Full_Parent)
7194 and then not Is_Generic_Type (Root_Type (Full_Parent)))
7196 -- Copy and adjust declaration to provide a completion for what
7197 -- is originally a private declaration. Indicate that full view
7198 -- is internally generated.
7200 Set_Comes_From_Source (Full_N, False);
7201 Set_Comes_From_Source (Full_Der, False);
7202 Set_Parent (Full_Der, Full_N);
7203 Set_Defining_Identifier (Full_N, Full_Der);
7205 -- If there are no constraints, adjust the subtype mark
7207 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
7208 N_Subtype_Indication
7210 Set_Subtype_Indication
7211 (Type_Definition (Full_N),
7212 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
7215 Insert_After (N, Full_N);
7217 -- Build full view of derived type from full view of parent which
7218 -- is now installed. Subprograms have been derived on the partial
7219 -- view, the completion does not derive them anew.
7221 if Ekind (Full_Parent) in Record_Kind then
7223 -- If parent type is tagged, the completion inherits the proper
7224 -- primitive operations.
7226 if Is_Tagged_Type (Parent_Type) then
7227 Build_Derived_Record_Type
7228 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7230 Build_Derived_Record_Type
7231 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7236 (Full_N, Full_Parent, Full_Der,
7237 Is_Completion => False, Derive_Subps => False);
7240 -- The full declaration has been introduced into the tree and
7241 -- processed in the step above. It should not be analyzed again
7242 -- (when encountered later in the current list of declarations)
7243 -- to prevent spurious name conflicts. The full entity remains
7246 Set_Analyzed (Full_N);
7250 Make_Defining_Identifier (Sloc (Derived_Type),
7251 Chars => Chars (Derived_Type));
7252 Set_Is_Itype (Full_Der);
7253 Set_Associated_Node_For_Itype (Full_Der, N);
7254 Set_Parent (Full_Der, N);
7256 (N, Full_Parent, Full_Der,
7257 Is_Completion => False, Derive_Subps => False);
7260 Set_Has_Private_Declaration (Full_Der);
7261 Set_Has_Private_Declaration (Derived_Type);
7263 Set_Scope (Full_Der, Scope (Derived_Type));
7264 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7265 Set_Has_Size_Clause (Full_Der, False);
7266 Set_Has_Alignment_Clause (Full_Der, False);
7267 Set_Has_Delayed_Freeze (Full_Der);
7268 Set_Is_Frozen (Full_Der, False);
7269 Set_Freeze_Node (Full_Der, Empty);
7270 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7271 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7273 -- The convention on the base type may be set in the private part
7274 -- and not propagated to the subtype until later, so we obtain the
7275 -- convention from the base type of the parent.
7277 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7280 -- Start of processing for Build_Derived_Private_Type
7283 if Is_Tagged_Type (Parent_Type) then
7284 Full_P := Full_View (Parent_Type);
7286 -- A type extension of a type with unknown discriminants is an
7287 -- indefinite type that the back-end cannot handle directly.
7288 -- We treat it as a private type, and build a completion that is
7289 -- derived from the full view of the parent, and hopefully has
7290 -- known discriminants.
7292 -- If the full view of the parent type has an underlying record view,
7293 -- use it to generate the underlying record view of this derived type
7294 -- (required for chains of derivations with unknown discriminants).
7296 -- Minor optimization: we avoid the generation of useless underlying
7297 -- record view entities if the private type declaration has unknown
7298 -- discriminants but its corresponding full view has no
7301 if Has_Unknown_Discriminants (Parent_Type)
7302 and then Present (Full_P)
7303 and then (Has_Discriminants (Full_P)
7304 or else Present (Underlying_Record_View (Full_P)))
7305 and then not In_Open_Scopes (Par_Scope)
7306 and then Expander_Active
7309 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7310 New_Ext : constant Node_Id :=
7312 (Record_Extension_Part (Type_Definition (N)));
7316 Build_Derived_Record_Type
7317 (N, Parent_Type, Derived_Type, Derive_Subps);
7319 -- Build anonymous completion, as a derivation from the full
7320 -- view of the parent. This is not a completion in the usual
7321 -- sense, because the current type is not private.
7324 Make_Full_Type_Declaration (Loc,
7325 Defining_Identifier => Full_Der,
7327 Make_Derived_Type_Definition (Loc,
7328 Subtype_Indication =>
7330 (Subtype_Indication (Type_Definition (N))),
7331 Record_Extension_Part => New_Ext));
7333 -- If the parent type has an underlying record view, use it
7334 -- here to build the new underlying record view.
7336 if Present (Underlying_Record_View (Full_P)) then
7338 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7340 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7341 Underlying_Record_View (Full_P));
7344 Install_Private_Declarations (Par_Scope);
7345 Install_Visible_Declarations (Par_Scope);
7346 Insert_Before (N, Decl);
7348 -- Mark entity as an underlying record view before analysis,
7349 -- to avoid generating the list of its primitive operations
7350 -- (which is not really required for this entity) and thus
7351 -- prevent spurious errors associated with missing overriding
7352 -- of abstract primitives (overridden only for Derived_Type).
7354 Set_Ekind (Full_Der, E_Record_Type);
7355 Set_Is_Underlying_Record_View (Full_Der);
7356 Set_Default_SSO (Full_Der);
7360 pragma Assert (Has_Discriminants (Full_Der)
7361 and then not Has_Unknown_Discriminants (Full_Der));
7363 Uninstall_Declarations (Par_Scope);
7365 -- Freeze the underlying record view, to prevent generation of
7366 -- useless dispatching information, which is simply shared with
7367 -- the real derived type.
7369 Set_Is_Frozen (Full_Der);
7371 -- If the derived type has access discriminants, create
7372 -- references to their anonymous types now, to prevent
7373 -- back-end problems when their first use is in generated
7374 -- bodies of primitives.
7380 E := First_Entity (Full_Der);
7382 while Present (E) loop
7383 if Ekind (E) = E_Discriminant
7384 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7386 Build_Itype_Reference (Etype (E), Decl);
7393 -- Set up links between real entity and underlying record view
7395 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7396 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7399 -- If discriminants are known, build derived record
7402 Build_Derived_Record_Type
7403 (N, Parent_Type, Derived_Type, Derive_Subps);
7408 elsif Has_Discriminants (Parent_Type) then
7410 -- Build partial view of derived type from partial view of parent.
7411 -- This must be done before building the full derivation because the
7412 -- second derivation will modify the discriminants of the first and
7413 -- the discriminants are chained with the rest of the components in
7414 -- the full derivation.
7416 Build_Derived_Record_Type
7417 (N, Parent_Type, Derived_Type, Derive_Subps);
7419 -- Build the full derivation if this is not the anonymous derived
7420 -- base type created by Build_Derived_Record_Type in the constrained
7421 -- case (see point 5. of its head comment) since we build it for the
7422 -- derived subtype. And skip it for protected types altogether, as
7423 -- gigi does not use these types directly.
7425 if Present (Full_View (Parent_Type))
7426 and then not Is_Itype (Derived_Type)
7427 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7430 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7432 Last_Discr : Entity_Id;
7435 -- If this is not a completion, construct the implicit full
7436 -- view by deriving from the full view of the parent type.
7437 -- But if this is a completion, the derived private type
7438 -- being built is a full view and the full derivation can
7439 -- only be its underlying full view.
7441 Build_Full_Derivation;
7443 if not Is_Completion then
7444 Set_Full_View (Derived_Type, Full_Der);
7446 Set_Underlying_Full_View (Derived_Type, Full_Der);
7449 if not Is_Base_Type (Derived_Type) then
7450 Set_Full_View (Der_Base, Base_Type (Full_Der));
7453 -- Copy the discriminant list from full view to the partial
7454 -- view (base type and its subtype). Gigi requires that the
7455 -- partial and full views have the same discriminants.
7457 -- Note that since the partial view points to discriminants
7458 -- in the full view, their scope will be that of the full
7459 -- view. This might cause some front end problems and need
7462 Discr := First_Discriminant (Base_Type (Full_Der));
7463 Set_First_Entity (Der_Base, Discr);
7466 Last_Discr := Discr;
7467 Next_Discriminant (Discr);
7468 exit when No (Discr);
7471 Set_Last_Entity (Der_Base, Last_Discr);
7472 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7473 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7475 Set_Stored_Constraint
7476 (Full_Der, Stored_Constraint (Derived_Type));
7480 elsif Present (Full_View (Parent_Type))
7481 and then Has_Discriminants (Full_View (Parent_Type))
7483 if Has_Unknown_Discriminants (Parent_Type)
7484 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7485 N_Subtype_Indication
7488 ("cannot constrain type with unknown discriminants",
7489 Subtype_Indication (Type_Definition (N)));
7493 -- If this is not a completion, construct the implicit full view by
7494 -- deriving from the full view of the parent type. But if this is a
7495 -- completion, the derived private type being built is a full view
7496 -- and the full derivation can only be its underlying full view.
7498 Build_Full_Derivation;
7500 if not Is_Completion then
7501 Set_Full_View (Derived_Type, Full_Der);
7503 Set_Underlying_Full_View (Derived_Type, Full_Der);
7506 -- In any case, the primitive operations are inherited from the
7507 -- parent type, not from the internal full view.
7509 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7511 if Derive_Subps then
7512 Derive_Subprograms (Parent_Type, Derived_Type);
7515 Set_Stored_Constraint (Derived_Type, No_Elist);
7517 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7520 -- Untagged type, No discriminants on either view
7522 if Nkind (Subtype_Indication (Type_Definition (N))) =
7523 N_Subtype_Indication
7526 ("illegal constraint on type without discriminants", N);
7529 if Present (Discriminant_Specifications (N))
7530 and then Present (Full_View (Parent_Type))
7531 and then not Is_Tagged_Type (Full_View (Parent_Type))
7533 Error_Msg_N ("cannot add discriminants to untagged type", N);
7536 Set_Stored_Constraint (Derived_Type, No_Elist);
7537 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7538 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7539 Set_Disable_Controlled (Derived_Type, Disable_Controlled
7541 Set_Has_Controlled_Component
7542 (Derived_Type, Has_Controlled_Component
7545 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7547 if not Is_Controlled_Active (Parent_Type) then
7548 Set_Finalize_Storage_Only
7549 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7552 -- If this is not a completion, construct the implicit full view by
7553 -- deriving from the full view of the parent type.
7555 -- ??? If the parent is untagged private and its completion is
7556 -- tagged, this mechanism will not work because we cannot derive from
7557 -- the tagged full view unless we have an extension.
7559 if Present (Full_View (Parent_Type))
7560 and then not Is_Tagged_Type (Full_View (Parent_Type))
7561 and then not Is_Completion
7563 Build_Full_Derivation;
7564 Set_Full_View (Derived_Type, Full_Der);
7568 Set_Has_Unknown_Discriminants (Derived_Type,
7569 Has_Unknown_Discriminants (Parent_Type));
7571 if Is_Private_Type (Derived_Type) then
7572 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7575 -- If the parent base type is in scope, add the derived type to its
7576 -- list of private dependents, because its full view may become
7577 -- visible subsequently (in a nested private part, a body, or in a
7578 -- further child unit).
7580 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7581 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7583 -- Check for unusual case where a type completed by a private
7584 -- derivation occurs within a package nested in a child unit, and
7585 -- the parent is declared in an ancestor.
7587 if Is_Child_Unit (Scope (Current_Scope))
7588 and then Is_Completion
7589 and then In_Private_Part (Current_Scope)
7590 and then Scope (Parent_Type) /= Current_Scope
7592 -- Note that if the parent has a completion in the private part,
7593 -- (which is itself a derivation from some other private type)
7594 -- it is that completion that is visible, there is no full view
7595 -- available, and no special processing is needed.
7597 and then Present (Full_View (Parent_Type))
7599 -- In this case, the full view of the parent type will become
7600 -- visible in the body of the enclosing child, and only then will
7601 -- the current type be possibly non-private. Build an underlying
7602 -- full view that will be installed when the enclosing child body
7605 if Present (Underlying_Full_View (Derived_Type)) then
7606 Full_Der := Underlying_Full_View (Derived_Type);
7608 Build_Full_Derivation;
7609 Set_Underlying_Full_View (Derived_Type, Full_Der);
7612 -- The full view will be used to swap entities on entry/exit to
7613 -- the body, and must appear in the entity list for the package.
7615 Append_Entity (Full_Der, Scope (Derived_Type));
7618 end Build_Derived_Private_Type;
7620 -------------------------------
7621 -- Build_Derived_Record_Type --
7622 -------------------------------
7626 -- Ideally we would like to use the same model of type derivation for
7627 -- tagged and untagged record types. Unfortunately this is not quite
7628 -- possible because the semantics of representation clauses is different
7629 -- for tagged and untagged records under inheritance. Consider the
7632 -- type R (...) is [tagged] record ... end record;
7633 -- type T (...) is new R (...) [with ...];
7635 -- The representation clauses for T can specify a completely different
7636 -- record layout from R's. Hence the same component can be placed in two
7637 -- very different positions in objects of type T and R. If R and T are
7638 -- tagged types, representation clauses for T can only specify the layout
7639 -- of non inherited components, thus components that are common in R and T
7640 -- have the same position in objects of type R and T.
7642 -- This has two implications. The first is that the entire tree for R's
7643 -- declaration needs to be copied for T in the untagged case, so that T
7644 -- can be viewed as a record type of its own with its own representation
7645 -- clauses. The second implication is the way we handle discriminants.
7646 -- Specifically, in the untagged case we need a way to communicate to Gigi
7647 -- what are the real discriminants in the record, while for the semantics
7648 -- we need to consider those introduced by the user to rename the
7649 -- discriminants in the parent type. This is handled by introducing the
7650 -- notion of stored discriminants. See below for more.
7652 -- Fortunately the way regular components are inherited can be handled in
7653 -- the same way in tagged and untagged types.
7655 -- To complicate things a bit more the private view of a private extension
7656 -- cannot be handled in the same way as the full view (for one thing the
7657 -- semantic rules are somewhat different). We will explain what differs
7660 -- 2. DISCRIMINANTS UNDER INHERITANCE
7662 -- The semantic rules governing the discriminants of derived types are
7665 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7666 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7668 -- If parent type has discriminants, then the discriminants that are
7669 -- declared in the derived type are [3.4 (11)]:
7671 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7674 -- o Otherwise, each discriminant of the parent type (implicitly declared
7675 -- in the same order with the same specifications). In this case, the
7676 -- discriminants are said to be "inherited", or if unknown in the parent
7677 -- are also unknown in the derived type.
7679 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7681 -- o The parent subtype must be constrained;
7683 -- o If the parent type is not a tagged type, then each discriminant of
7684 -- the derived type must be used in the constraint defining a parent
7685 -- subtype. [Implementation note: This ensures that the new discriminant
7686 -- can share storage with an existing discriminant.]
7688 -- For the derived type each discriminant of the parent type is either
7689 -- inherited, constrained to equal some new discriminant of the derived
7690 -- type, or constrained to the value of an expression.
7692 -- When inherited or constrained to equal some new discriminant, the
7693 -- parent discriminant and the discriminant of the derived type are said
7696 -- If a discriminant of the parent type is constrained to a specific value
7697 -- in the derived type definition, then the discriminant is said to be
7698 -- "specified" by that derived type definition.
7700 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7702 -- We have spoken about stored discriminants in point 1 (introduction)
7703 -- above. There are two sort of stored discriminants: implicit and
7704 -- explicit. As long as the derived type inherits the same discriminants as
7705 -- the root record type, stored discriminants are the same as regular
7706 -- discriminants, and are said to be implicit. However, if any discriminant
7707 -- in the root type was renamed in the derived type, then the derived
7708 -- type will contain explicit stored discriminants. Explicit stored
7709 -- discriminants are discriminants in addition to the semantically visible
7710 -- discriminants defined for the derived type. Stored discriminants are
7711 -- used by Gigi to figure out what are the physical discriminants in
7712 -- objects of the derived type (see precise definition in einfo.ads).
7713 -- As an example, consider the following:
7715 -- type R (D1, D2, D3 : Int) is record ... end record;
7716 -- type T1 is new R;
7717 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7718 -- type T3 is new T2;
7719 -- type T4 (Y : Int) is new T3 (Y, 99);
7721 -- The following table summarizes the discriminants and stored
7722 -- discriminants in R and T1 through T4.
7724 -- Type Discrim Stored Discrim Comment
7725 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7726 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7727 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7728 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7729 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7731 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7732 -- find the corresponding discriminant in the parent type, while
7733 -- Original_Record_Component (abbreviated ORC below), the actual physical
7734 -- component that is renamed. Finally the field Is_Completely_Hidden
7735 -- (abbreviated ICH below) is set for all explicit stored discriminants
7736 -- (see einfo.ads for more info). For the above example this gives:
7738 -- Discrim CD ORC ICH
7739 -- ^^^^^^^ ^^ ^^^ ^^^
7740 -- D1 in R empty itself no
7741 -- D2 in R empty itself no
7742 -- D3 in R empty itself no
7744 -- D1 in T1 D1 in R itself no
7745 -- D2 in T1 D2 in R itself no
7746 -- D3 in T1 D3 in R itself no
7748 -- X1 in T2 D3 in T1 D3 in T2 no
7749 -- X2 in T2 D1 in T1 D1 in T2 no
7750 -- D1 in T2 empty itself yes
7751 -- D2 in T2 empty itself yes
7752 -- D3 in T2 empty itself yes
7754 -- X1 in T3 X1 in T2 D3 in T3 no
7755 -- X2 in T3 X2 in T2 D1 in T3 no
7756 -- D1 in T3 empty itself yes
7757 -- D2 in T3 empty itself yes
7758 -- D3 in T3 empty itself yes
7760 -- Y in T4 X1 in T3 D3 in T3 no
7761 -- D1 in T3 empty itself yes
7762 -- D2 in T3 empty itself yes
7763 -- D3 in T3 empty itself yes
7765 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7767 -- Type derivation for tagged types is fairly straightforward. If no
7768 -- discriminants are specified by the derived type, these are inherited
7769 -- from the parent. No explicit stored discriminants are ever necessary.
7770 -- The only manipulation that is done to the tree is that of adding a
7771 -- _parent field with parent type and constrained to the same constraint
7772 -- specified for the parent in the derived type definition. For instance:
7774 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7775 -- type T1 is new R with null record;
7776 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7778 -- are changed into:
7780 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7781 -- _parent : R (D1, D2, D3);
7784 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7785 -- _parent : T1 (X2, 88, X1);
7788 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7789 -- ORC and ICH fields are:
7791 -- Discrim CD ORC ICH
7792 -- ^^^^^^^ ^^ ^^^ ^^^
7793 -- D1 in R empty itself no
7794 -- D2 in R empty itself no
7795 -- D3 in R empty itself no
7797 -- D1 in T1 D1 in R D1 in R no
7798 -- D2 in T1 D2 in R D2 in R no
7799 -- D3 in T1 D3 in R D3 in R no
7801 -- X1 in T2 D3 in T1 D3 in R no
7802 -- X2 in T2 D1 in T1 D1 in R no
7804 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7806 -- Regardless of whether we dealing with a tagged or untagged type
7807 -- we will transform all derived type declarations of the form
7809 -- type T is new R (...) [with ...];
7811 -- subtype S is R (...);
7812 -- type T is new S [with ...];
7814 -- type BT is new R [with ...];
7815 -- subtype T is BT (...);
7817 -- That is, the base derived type is constrained only if it has no
7818 -- discriminants. The reason for doing this is that GNAT's semantic model
7819 -- assumes that a base type with discriminants is unconstrained.
7821 -- Note that, strictly speaking, the above transformation is not always
7822 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7824 -- procedure B34011A is
7825 -- type REC (D : integer := 0) is record
7830 -- type T6 is new Rec;
7831 -- function F return T6;
7836 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7839 -- The definition of Q6.U is illegal. However transforming Q6.U into
7841 -- type BaseU is new T6;
7842 -- subtype U is BaseU (Q6.F.I)
7844 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7845 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7846 -- the transformation described above.
7848 -- There is another instance where the above transformation is incorrect.
7852 -- type Base (D : Integer) is tagged null record;
7853 -- procedure P (X : Base);
7855 -- type Der is new Base (2) with null record;
7856 -- procedure P (X : Der);
7859 -- Then the above transformation turns this into
7861 -- type Der_Base is new Base with null record;
7862 -- -- procedure P (X : Base) is implicitly inherited here
7863 -- -- as procedure P (X : Der_Base).
7865 -- subtype Der is Der_Base (2);
7866 -- procedure P (X : Der);
7867 -- -- The overriding of P (X : Der_Base) is illegal since we
7868 -- -- have a parameter conformance problem.
7870 -- To get around this problem, after having semantically processed Der_Base
7871 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7872 -- Discriminant_Constraint from Der so that when parameter conformance is
7873 -- checked when P is overridden, no semantic errors are flagged.
7875 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7877 -- Regardless of whether we are dealing with a tagged or untagged type
7878 -- we will transform all derived type declarations of the form
7880 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7881 -- type T is new R [with ...];
7883 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7885 -- The reason for such transformation is that it allows us to implement a
7886 -- very clean form of component inheritance as explained below.
7888 -- Note that this transformation is not achieved by direct tree rewriting
7889 -- and manipulation, but rather by redoing the semantic actions that the
7890 -- above transformation will entail. This is done directly in routine
7891 -- Inherit_Components.
7893 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7895 -- In both tagged and untagged derived types, regular non discriminant
7896 -- components are inherited in the derived type from the parent type. In
7897 -- the absence of discriminants component, inheritance is straightforward
7898 -- as components can simply be copied from the parent.
7900 -- If the parent has discriminants, inheriting components constrained with
7901 -- these discriminants requires caution. Consider the following example:
7903 -- type R (D1, D2 : Positive) is [tagged] record
7904 -- S : String (D1 .. D2);
7907 -- type T1 is new R [with null record];
7908 -- type T2 (X : positive) is new R (1, X) [with null record];
7910 -- As explained in 6. above, T1 is rewritten as
7911 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7912 -- which makes the treatment for T1 and T2 identical.
7914 -- What we want when inheriting S, is that references to D1 and D2 in R are
7915 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7916 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7917 -- with either discriminant references in the derived type or expressions.
7918 -- This replacement is achieved as follows: before inheriting R's
7919 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7920 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7921 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7922 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7923 -- by String (1 .. X).
7925 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7927 -- We explain here the rules governing private type extensions relevant to
7928 -- type derivation. These rules are explained on the following example:
7930 -- type D [(...)] is new A [(...)] with private; <-- partial view
7931 -- type D [(...)] is new P [(...)] with null record; <-- full view
7933 -- Type A is called the ancestor subtype of the private extension.
7934 -- Type P is the parent type of the full view of the private extension. It
7935 -- must be A or a type derived from A.
7937 -- The rules concerning the discriminants of private type extensions are
7940 -- o If a private extension inherits known discriminants from the ancestor
7941 -- subtype, then the full view must also inherit its discriminants from
7942 -- the ancestor subtype and the parent subtype of the full view must be
7943 -- constrained if and only if the ancestor subtype is constrained.
7945 -- o If a partial view has unknown discriminants, then the full view may
7946 -- define a definite or an indefinite subtype, with or without
7949 -- o If a partial view has neither known nor unknown discriminants, then
7950 -- the full view must define a definite subtype.
7952 -- o If the ancestor subtype of a private extension has constrained
7953 -- discriminants, then the parent subtype of the full view must impose a
7954 -- statically matching constraint on those discriminants.
7956 -- This means that only the following forms of private extensions are
7959 -- type D is new A with private; <-- partial view
7960 -- type D is new P with null record; <-- full view
7962 -- If A has no discriminants than P has no discriminants, otherwise P must
7963 -- inherit A's discriminants.
7965 -- type D is new A (...) with private; <-- partial view
7966 -- type D is new P (:::) with null record; <-- full view
7968 -- P must inherit A's discriminants and (...) and (:::) must statically
7971 -- subtype A is R (...);
7972 -- type D is new A with private; <-- partial view
7973 -- type D is new P with null record; <-- full view
7975 -- P must have inherited R's discriminants and must be derived from A or
7976 -- any of its subtypes.
7978 -- type D (..) is new A with private; <-- partial view
7979 -- type D (..) is new P [(:::)] with null record; <-- full view
7981 -- No specific constraints on P's discriminants or constraint (:::).
7982 -- Note that A can be unconstrained, but the parent subtype P must either
7983 -- be constrained or (:::) must be present.
7985 -- type D (..) is new A [(...)] with private; <-- partial view
7986 -- type D (..) is new P [(:::)] with null record; <-- full view
7988 -- P's constraints on A's discriminants must statically match those
7989 -- imposed by (...).
7991 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7993 -- The full view of a private extension is handled exactly as described
7994 -- above. The model chose for the private view of a private extension is
7995 -- the same for what concerns discriminants (i.e. they receive the same
7996 -- treatment as in the tagged case). However, the private view of the
7997 -- private extension always inherits the components of the parent base,
7998 -- without replacing any discriminant reference. Strictly speaking this is
7999 -- incorrect. However, Gigi never uses this view to generate code so this
8000 -- is a purely semantic issue. In theory, a set of transformations similar
8001 -- to those given in 5. and 6. above could be applied to private views of
8002 -- private extensions to have the same model of component inheritance as
8003 -- for non private extensions. However, this is not done because it would
8004 -- further complicate private type processing. Semantically speaking, this
8005 -- leaves us in an uncomfortable situation. As an example consider:
8008 -- type R (D : integer) is tagged record
8009 -- S : String (1 .. D);
8011 -- procedure P (X : R);
8012 -- type T is new R (1) with private;
8014 -- type T is new R (1) with null record;
8017 -- This is transformed into:
8020 -- type R (D : integer) is tagged record
8021 -- S : String (1 .. D);
8023 -- procedure P (X : R);
8024 -- type T is new R (1) with private;
8026 -- type BaseT is new R with null record;
8027 -- subtype T is BaseT (1);
8030 -- (strictly speaking the above is incorrect Ada)
8032 -- From the semantic standpoint the private view of private extension T
8033 -- should be flagged as constrained since one can clearly have
8037 -- in a unit withing Pack. However, when deriving subprograms for the
8038 -- private view of private extension T, T must be seen as unconstrained
8039 -- since T has discriminants (this is a constraint of the current
8040 -- subprogram derivation model). Thus, when processing the private view of
8041 -- a private extension such as T, we first mark T as unconstrained, we
8042 -- process it, we perform program derivation and just before returning from
8043 -- Build_Derived_Record_Type we mark T as constrained.
8045 -- ??? Are there are other uncomfortable cases that we will have to
8048 -- 10. RECORD_TYPE_WITH_PRIVATE complications
8050 -- Types that are derived from a visible record type and have a private
8051 -- extension present other peculiarities. They behave mostly like private
8052 -- types, but if they have primitive operations defined, these will not
8053 -- have the proper signatures for further inheritance, because other
8054 -- primitive operations will use the implicit base that we define for
8055 -- private derivations below. This affect subprogram inheritance (see
8056 -- Derive_Subprograms for details). We also derive the implicit base from
8057 -- the base type of the full view, so that the implicit base is a record
8058 -- type and not another private type, This avoids infinite loops.
8060 procedure Build_Derived_Record_Type
8062 Parent_Type : Entity_Id;
8063 Derived_Type : Entity_Id;
8064 Derive_Subps : Boolean := True)
8066 Discriminant_Specs : constant Boolean :=
8067 Present (Discriminant_Specifications (N));
8068 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
8069 Loc : constant Source_Ptr := Sloc (N);
8070 Private_Extension : constant Boolean :=
8071 Nkind (N) = N_Private_Extension_Declaration;
8072 Assoc_List : Elist_Id;
8073 Constraint_Present : Boolean;
8075 Discrim : Entity_Id;
8077 Inherit_Discrims : Boolean := False;
8078 Last_Discrim : Entity_Id;
8079 New_Base : Entity_Id;
8081 New_Discrs : Elist_Id;
8082 New_Indic : Node_Id;
8083 Parent_Base : Entity_Id;
8084 Save_Etype : Entity_Id;
8085 Save_Discr_Constr : Elist_Id;
8086 Save_Next_Entity : Entity_Id;
8089 Discs : Elist_Id := New_Elmt_List;
8090 -- An empty Discs list means that there were no constraints in the
8091 -- subtype indication or that there was an error processing it.
8094 if Ekind (Parent_Type) = E_Record_Type_With_Private
8095 and then Present (Full_View (Parent_Type))
8096 and then Has_Discriminants (Parent_Type)
8098 Parent_Base := Base_Type (Full_View (Parent_Type));
8100 Parent_Base := Base_Type (Parent_Type);
8103 -- AI05-0115 : if this is a derivation from a private type in some
8104 -- other scope that may lead to invisible components for the derived
8105 -- type, mark it accordingly.
8107 if Is_Private_Type (Parent_Type) then
8108 if Scope (Parent_Type) = Scope (Derived_Type) then
8111 elsif In_Open_Scopes (Scope (Parent_Type))
8112 and then In_Private_Part (Scope (Parent_Type))
8117 Set_Has_Private_Ancestor (Derived_Type);
8121 Set_Has_Private_Ancestor
8122 (Derived_Type, Has_Private_Ancestor (Parent_Type));
8125 -- Before we start the previously documented transformations, here is
8126 -- little fix for size and alignment of tagged types. Normally when we
8127 -- derive type D from type P, we copy the size and alignment of P as the
8128 -- default for D, and in the absence of explicit representation clauses
8129 -- for D, the size and alignment are indeed the same as the parent.
8131 -- But this is wrong for tagged types, since fields may be added, and
8132 -- the default size may need to be larger, and the default alignment may
8133 -- need to be larger.
8135 -- We therefore reset the size and alignment fields in the tagged case.
8136 -- Note that the size and alignment will in any case be at least as
8137 -- large as the parent type (since the derived type has a copy of the
8138 -- parent type in the _parent field)
8140 -- The type is also marked as being tagged here, which is needed when
8141 -- processing components with a self-referential anonymous access type
8142 -- in the call to Check_Anonymous_Access_Components below. Note that
8143 -- this flag is also set later on for completeness.
8146 Set_Is_Tagged_Type (Derived_Type);
8147 Init_Size_Align (Derived_Type);
8150 -- STEP 0a: figure out what kind of derived type declaration we have
8152 if Private_Extension then
8154 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
8155 Set_Default_SSO (Derived_Type);
8158 Type_Def := Type_Definition (N);
8160 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8161 -- Parent_Base can be a private type or private extension. However,
8162 -- for tagged types with an extension the newly added fields are
8163 -- visible and hence the Derived_Type is always an E_Record_Type.
8164 -- (except that the parent may have its own private fields).
8165 -- For untagged types we preserve the Ekind of the Parent_Base.
8167 if Present (Record_Extension_Part (Type_Def)) then
8168 Set_Ekind (Derived_Type, E_Record_Type);
8169 Set_Default_SSO (Derived_Type);
8171 -- Create internal access types for components with anonymous
8174 if Ada_Version >= Ada_2005 then
8175 Check_Anonymous_Access_Components
8176 (N, Derived_Type, Derived_Type,
8177 Component_List (Record_Extension_Part (Type_Def)));
8181 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8185 -- Indic can either be an N_Identifier if the subtype indication
8186 -- contains no constraint or an N_Subtype_Indication if the subtype
8187 -- indication has a constraint.
8189 Indic := Subtype_Indication (Type_Def);
8190 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
8192 -- Check that the type has visible discriminants. The type may be
8193 -- a private type with unknown discriminants whose full view has
8194 -- discriminants which are invisible.
8196 if Constraint_Present then
8197 if not Has_Discriminants (Parent_Base)
8199 (Has_Unknown_Discriminants (Parent_Base)
8200 and then Is_Private_Type (Parent_Base))
8203 ("invalid constraint: type has no discriminant",
8204 Constraint (Indic));
8206 Constraint_Present := False;
8207 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8209 elsif Is_Constrained (Parent_Type) then
8211 ("invalid constraint: parent type is already constrained",
8212 Constraint (Indic));
8214 Constraint_Present := False;
8215 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
8219 -- STEP 0b: If needed, apply transformation given in point 5. above
8221 if not Private_Extension
8222 and then Has_Discriminants (Parent_Type)
8223 and then not Discriminant_Specs
8224 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
8226 -- First, we must analyze the constraint (see comment in point 5.)
8227 -- The constraint may come from the subtype indication of the full
8230 if Constraint_Present then
8231 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8233 -- If there is no explicit constraint, there might be one that is
8234 -- inherited from a constrained parent type. In that case verify that
8235 -- it conforms to the constraint in the partial view. In perverse
8236 -- cases the parent subtypes of the partial and full view can have
8237 -- different constraints.
8239 elsif Present (Stored_Constraint (Parent_Type)) then
8240 New_Discrs := Stored_Constraint (Parent_Type);
8243 New_Discrs := No_Elist;
8246 if Has_Discriminants (Derived_Type)
8247 and then Has_Private_Declaration (Derived_Type)
8248 and then Present (Discriminant_Constraint (Derived_Type))
8249 and then Present (New_Discrs)
8251 -- Verify that constraints of the full view statically match
8252 -- those given in the partial view.
8258 C1 := First_Elmt (New_Discrs);
8259 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8260 while Present (C1) and then Present (C2) loop
8261 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8263 (Is_OK_Static_Expression (Node (C1))
8264 and then Is_OK_Static_Expression (Node (C2))
8266 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8271 if Constraint_Present then
8273 ("constraint not conformant to previous declaration",
8277 ("constraint of full view is incompatible "
8278 & "with partial view", N);
8288 -- Insert and analyze the declaration for the unconstrained base type
8290 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8293 Make_Full_Type_Declaration (Loc,
8294 Defining_Identifier => New_Base,
8296 Make_Derived_Type_Definition (Loc,
8297 Abstract_Present => Abstract_Present (Type_Def),
8298 Limited_Present => Limited_Present (Type_Def),
8299 Subtype_Indication =>
8300 New_Occurrence_Of (Parent_Base, Loc),
8301 Record_Extension_Part =>
8302 Relocate_Node (Record_Extension_Part (Type_Def)),
8303 Interface_List => Interface_List (Type_Def)));
8305 Set_Parent (New_Decl, Parent (N));
8306 Mark_Rewrite_Insertion (New_Decl);
8307 Insert_Before (N, New_Decl);
8309 -- In the extension case, make sure ancestor is frozen appropriately
8310 -- (see also non-discriminated case below).
8312 if Present (Record_Extension_Part (Type_Def))
8313 or else Is_Interface (Parent_Base)
8315 Freeze_Before (New_Decl, Parent_Type);
8318 -- Note that this call passes False for the Derive_Subps parameter
8319 -- because subprogram derivation is deferred until after creating
8320 -- the subtype (see below).
8323 (New_Decl, Parent_Base, New_Base,
8324 Is_Completion => False, Derive_Subps => False);
8326 -- ??? This needs re-examination to determine whether the
8327 -- above call can simply be replaced by a call to Analyze.
8329 Set_Analyzed (New_Decl);
8331 -- Insert and analyze the declaration for the constrained subtype
8333 if Constraint_Present then
8335 Make_Subtype_Indication (Loc,
8336 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8337 Constraint => Relocate_Node (Constraint (Indic)));
8341 Constr_List : constant List_Id := New_List;
8346 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8347 while Present (C) loop
8350 -- It is safe here to call New_Copy_Tree since we called
8351 -- Force_Evaluation on each constraint previously
8352 -- in Build_Discriminant_Constraints.
8354 Append (New_Copy_Tree (Expr), To => Constr_List);
8360 Make_Subtype_Indication (Loc,
8361 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8363 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8368 Make_Subtype_Declaration (Loc,
8369 Defining_Identifier => Derived_Type,
8370 Subtype_Indication => New_Indic));
8374 -- Derivation of subprograms must be delayed until the full subtype
8375 -- has been established, to ensure proper overriding of subprograms
8376 -- inherited by full types. If the derivations occurred as part of
8377 -- the call to Build_Derived_Type above, then the check for type
8378 -- conformance would fail because earlier primitive subprograms
8379 -- could still refer to the full type prior the change to the new
8380 -- subtype and hence would not match the new base type created here.
8381 -- Subprograms are not derived, however, when Derive_Subps is False
8382 -- (since otherwise there could be redundant derivations).
8384 if Derive_Subps then
8385 Derive_Subprograms (Parent_Type, Derived_Type);
8388 -- For tagged types the Discriminant_Constraint of the new base itype
8389 -- is inherited from the first subtype so that no subtype conformance
8390 -- problem arise when the first subtype overrides primitive
8391 -- operations inherited by the implicit base type.
8394 Set_Discriminant_Constraint
8395 (New_Base, Discriminant_Constraint (Derived_Type));
8401 -- If we get here Derived_Type will have no discriminants or it will be
8402 -- a discriminated unconstrained base type.
8404 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8408 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8409 -- The declaration of a specific descendant of an interface type
8410 -- freezes the interface type (RM 13.14).
8412 if not Private_Extension or else Is_Interface (Parent_Base) then
8413 Freeze_Before (N, Parent_Type);
8416 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8417 -- cannot be declared at a deeper level than its parent type is
8418 -- removed. The check on derivation within a generic body is also
8419 -- relaxed, but there's a restriction that a derived tagged type
8420 -- cannot be declared in a generic body if it's derived directly
8421 -- or indirectly from a formal type of that generic.
8423 if Ada_Version >= Ada_2005 then
8424 if Present (Enclosing_Generic_Body (Derived_Type)) then
8426 Ancestor_Type : Entity_Id;
8429 -- Check to see if any ancestor of the derived type is a
8432 Ancestor_Type := Parent_Type;
8433 while not Is_Generic_Type (Ancestor_Type)
8434 and then Etype (Ancestor_Type) /= Ancestor_Type
8436 Ancestor_Type := Etype (Ancestor_Type);
8439 -- If the derived type does have a formal type as an
8440 -- ancestor, then it's an error if the derived type is
8441 -- declared within the body of the generic unit that
8442 -- declares the formal type in its generic formal part. It's
8443 -- sufficient to check whether the ancestor type is declared
8444 -- inside the same generic body as the derived type (such as
8445 -- within a nested generic spec), in which case the
8446 -- derivation is legal. If the formal type is declared
8447 -- outside of that generic body, then it's guaranteed that
8448 -- the derived type is declared within the generic body of
8449 -- the generic unit declaring the formal type.
8451 if Is_Generic_Type (Ancestor_Type)
8452 and then Enclosing_Generic_Body (Ancestor_Type) /=
8453 Enclosing_Generic_Body (Derived_Type)
8456 ("parent type of& must not be descendant of formal type"
8457 & " of an enclosing generic body",
8458 Indic, Derived_Type);
8463 elsif Type_Access_Level (Derived_Type) /=
8464 Type_Access_Level (Parent_Type)
8465 and then not Is_Generic_Type (Derived_Type)
8467 if Is_Controlled (Parent_Type) then
8469 ("controlled type must be declared at the library level",
8473 ("type extension at deeper accessibility level than parent",
8479 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8482 and then GB /= Enclosing_Generic_Body (Parent_Base)
8485 ("parent type of& must not be outside generic body"
8487 Indic, Derived_Type);
8493 -- Ada 2005 (AI-251)
8495 if Ada_Version >= Ada_2005 and then Is_Tagged then
8497 -- "The declaration of a specific descendant of an interface type
8498 -- freezes the interface type" (RM 13.14).
8503 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8504 Iface := First (Interface_List (Type_Def));
8505 while Present (Iface) loop
8506 Freeze_Before (N, Etype (Iface));
8513 -- STEP 1b : preliminary cleanup of the full view of private types
8515 -- If the type is already marked as having discriminants, then it's the
8516 -- completion of a private type or private extension and we need to
8517 -- retain the discriminants from the partial view if the current
8518 -- declaration has Discriminant_Specifications so that we can verify
8519 -- conformance. However, we must remove any existing components that
8520 -- were inherited from the parent (and attached in Copy_And_Swap)
8521 -- because the full type inherits all appropriate components anyway, and
8522 -- we do not want the partial view's components interfering.
8524 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8525 Discrim := First_Discriminant (Derived_Type);
8527 Last_Discrim := Discrim;
8528 Next_Discriminant (Discrim);
8529 exit when No (Discrim);
8532 Set_Last_Entity (Derived_Type, Last_Discrim);
8534 -- In all other cases wipe out the list of inherited components (even
8535 -- inherited discriminants), it will be properly rebuilt here.
8538 Set_First_Entity (Derived_Type, Empty);
8539 Set_Last_Entity (Derived_Type, Empty);
8542 -- STEP 1c: Initialize some flags for the Derived_Type
8544 -- The following flags must be initialized here so that
8545 -- Process_Discriminants can check that discriminants of tagged types do
8546 -- not have a default initial value and that access discriminants are
8547 -- only specified for limited records. For completeness, these flags are
8548 -- also initialized along with all the other flags below.
8550 -- AI-419: Limitedness is not inherited from an interface parent, so to
8551 -- be limited in that case the type must be explicitly declared as
8552 -- limited. However, task and protected interfaces are always limited.
8554 if Limited_Present (Type_Def) then
8555 Set_Is_Limited_Record (Derived_Type);
8557 elsif Is_Limited_Record (Parent_Type)
8558 or else (Present (Full_View (Parent_Type))
8559 and then Is_Limited_Record (Full_View (Parent_Type)))
8561 if not Is_Interface (Parent_Type)
8562 or else Is_Synchronized_Interface (Parent_Type)
8563 or else Is_Protected_Interface (Parent_Type)
8564 or else Is_Task_Interface (Parent_Type)
8566 Set_Is_Limited_Record (Derived_Type);
8570 -- STEP 2a: process discriminants of derived type if any
8572 Push_Scope (Derived_Type);
8574 if Discriminant_Specs then
8575 Set_Has_Unknown_Discriminants (Derived_Type, False);
8577 -- The following call initializes fields Has_Discriminants and
8578 -- Discriminant_Constraint, unless we are processing the completion
8579 -- of a private type declaration.
8581 Check_Or_Process_Discriminants (N, Derived_Type);
8583 -- For untagged types, the constraint on the Parent_Type must be
8584 -- present and is used to rename the discriminants.
8586 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8587 Error_Msg_N ("untagged parent must have discriminants", Indic);
8589 elsif not Is_Tagged and then not Constraint_Present then
8591 ("discriminant constraint needed for derived untagged records",
8594 -- Otherwise the parent subtype must be constrained unless we have a
8595 -- private extension.
8597 elsif not Constraint_Present
8598 and then not Private_Extension
8599 and then not Is_Constrained (Parent_Type)
8602 ("unconstrained type not allowed in this context", Indic);
8604 elsif Constraint_Present then
8605 -- The following call sets the field Corresponding_Discriminant
8606 -- for the discriminants in the Derived_Type.
8608 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8610 -- For untagged types all new discriminants must rename
8611 -- discriminants in the parent. For private extensions new
8612 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8614 Discrim := First_Discriminant (Derived_Type);
8615 while Present (Discrim) loop
8617 and then No (Corresponding_Discriminant (Discrim))
8620 ("new discriminants must constrain old ones", Discrim);
8622 elsif Private_Extension
8623 and then Present (Corresponding_Discriminant (Discrim))
8626 ("only static constraints allowed for parent"
8627 & " discriminants in the partial view", Indic);
8631 -- If a new discriminant is used in the constraint, then its
8632 -- subtype must be statically compatible with the parent
8633 -- discriminant's subtype (3.7(15)).
8635 -- However, if the record contains an array constrained by
8636 -- the discriminant but with some different bound, the compiler
8637 -- attemps to create a smaller range for the discriminant type.
8638 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8639 -- the discriminant type is a scalar type, the check must use
8640 -- the original discriminant type in the parent declaration.
8643 Corr_Disc : constant Entity_Id :=
8644 Corresponding_Discriminant (Discrim);
8645 Disc_Type : constant Entity_Id := Etype (Discrim);
8646 Corr_Type : Entity_Id;
8649 if Present (Corr_Disc) then
8650 if Is_Scalar_Type (Disc_Type) then
8652 Entity (Discriminant_Type (Parent (Corr_Disc)));
8654 Corr_Type := Etype (Corr_Disc);
8658 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8661 ("subtype must be compatible "
8662 & "with parent discriminant",
8668 Next_Discriminant (Discrim);
8671 -- Check whether the constraints of the full view statically
8672 -- match those imposed by the parent subtype [7.3(13)].
8674 if Present (Stored_Constraint (Derived_Type)) then
8679 C1 := First_Elmt (Discs);
8680 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8681 while Present (C1) and then Present (C2) loop
8683 Fully_Conformant_Expressions (Node (C1), Node (C2))
8686 ("not conformant with previous declaration",
8697 -- STEP 2b: No new discriminants, inherit discriminants if any
8700 if Private_Extension then
8701 Set_Has_Unknown_Discriminants
8703 Has_Unknown_Discriminants (Parent_Type)
8704 or else Unknown_Discriminants_Present (N));
8706 -- The partial view of the parent may have unknown discriminants,
8707 -- but if the full view has discriminants and the parent type is
8708 -- in scope they must be inherited.
8710 elsif Has_Unknown_Discriminants (Parent_Type)
8712 (not Has_Discriminants (Parent_Type)
8713 or else not In_Open_Scopes (Scope (Parent_Type)))
8715 Set_Has_Unknown_Discriminants (Derived_Type);
8718 if not Has_Unknown_Discriminants (Derived_Type)
8719 and then not Has_Unknown_Discriminants (Parent_Base)
8720 and then Has_Discriminants (Parent_Type)
8722 Inherit_Discrims := True;
8723 Set_Has_Discriminants
8724 (Derived_Type, True);
8725 Set_Discriminant_Constraint
8726 (Derived_Type, Discriminant_Constraint (Parent_Base));
8729 -- The following test is true for private types (remember
8730 -- transformation 5. is not applied to those) and in an error
8733 if Constraint_Present then
8734 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8737 -- For now mark a new derived type as constrained only if it has no
8738 -- discriminants. At the end of Build_Derived_Record_Type we properly
8739 -- set this flag in the case of private extensions. See comments in
8740 -- point 9. just before body of Build_Derived_Record_Type.
8744 not (Inherit_Discrims
8745 or else Has_Unknown_Discriminants (Derived_Type)));
8748 -- STEP 3: initialize fields of derived type
8750 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8751 Set_Stored_Constraint (Derived_Type, No_Elist);
8753 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8754 -- but cannot be interfaces
8756 if not Private_Extension
8757 and then Ekind (Derived_Type) /= E_Private_Type
8758 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8760 if Interface_Present (Type_Def) then
8761 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8764 Set_Interfaces (Derived_Type, No_Elist);
8767 -- Fields inherited from the Parent_Type
8769 Set_Has_Specified_Layout
8770 (Derived_Type, Has_Specified_Layout (Parent_Type));
8771 Set_Is_Limited_Composite
8772 (Derived_Type, Is_Limited_Composite (Parent_Type));
8773 Set_Is_Private_Composite
8774 (Derived_Type, Is_Private_Composite (Parent_Type));
8776 if Is_Tagged_Type (Parent_Type) then
8777 Set_No_Tagged_Streams_Pragma
8778 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8781 -- Fields inherited from the Parent_Base
8783 Set_Has_Controlled_Component
8784 (Derived_Type, Has_Controlled_Component (Parent_Base));
8785 Set_Has_Non_Standard_Rep
8786 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8787 Set_Has_Primitive_Operations
8788 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8790 -- Fields inherited from the Parent_Base in the non-private case
8792 if Ekind (Derived_Type) = E_Record_Type then
8793 Set_Has_Complex_Representation
8794 (Derived_Type, Has_Complex_Representation (Parent_Base));
8797 -- Fields inherited from the Parent_Base for record types
8799 if Is_Record_Type (Derived_Type) then
8801 Parent_Full : Entity_Id;
8804 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8805 -- Parent_Base can be a private type or private extension. Go
8806 -- to the full view here to get the E_Record_Type specific flags.
8808 if Present (Full_View (Parent_Base)) then
8809 Parent_Full := Full_View (Parent_Base);
8811 Parent_Full := Parent_Base;
8814 Set_OK_To_Reorder_Components
8815 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8819 -- Set fields for private derived types
8821 if Is_Private_Type (Derived_Type) then
8822 Set_Depends_On_Private (Derived_Type, True);
8823 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8825 -- Inherit fields from non private record types. If this is the
8826 -- completion of a derivation from a private type, the parent itself
8827 -- is private, and the attributes come from its full view, which must
8831 if Is_Private_Type (Parent_Base)
8832 and then not Is_Record_Type (Parent_Base)
8834 Set_Component_Alignment
8835 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8837 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8839 Set_Component_Alignment
8840 (Derived_Type, Component_Alignment (Parent_Base));
8842 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8846 -- Set fields for tagged types
8849 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8851 -- All tagged types defined in Ada.Finalization are controlled
8853 if Chars (Scope (Derived_Type)) = Name_Finalization
8854 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8855 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8857 Set_Is_Controlled (Derived_Type);
8859 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8862 -- Minor optimization: there is no need to generate the class-wide
8863 -- entity associated with an underlying record view.
8865 if not Is_Underlying_Record_View (Derived_Type) then
8866 Make_Class_Wide_Type (Derived_Type);
8869 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8871 if Has_Discriminants (Derived_Type)
8872 and then Constraint_Present
8874 Set_Stored_Constraint
8875 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8878 if Ada_Version >= Ada_2005 then
8880 Ifaces_List : Elist_Id;
8883 -- Checks rules 3.9.4 (13/2 and 14/2)
8885 if Comes_From_Source (Derived_Type)
8886 and then not Is_Private_Type (Derived_Type)
8887 and then Is_Interface (Parent_Type)
8888 and then not Is_Interface (Derived_Type)
8890 if Is_Task_Interface (Parent_Type) then
8892 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8895 elsif Is_Protected_Interface (Parent_Type) then
8897 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8902 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8904 Check_Interfaces (N, Type_Def);
8906 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8907 -- not already in the parents.
8911 Ifaces_List => Ifaces_List,
8912 Exclude_Parents => True);
8914 Set_Interfaces (Derived_Type, Ifaces_List);
8916 -- If the derived type is the anonymous type created for
8917 -- a declaration whose parent has a constraint, propagate
8918 -- the interface list to the source type. This must be done
8919 -- prior to the completion of the analysis of the source type
8920 -- because the components in the extension may contain current
8921 -- instances whose legality depends on some ancestor.
8923 if Is_Itype (Derived_Type) then
8925 Def : constant Node_Id :=
8926 Associated_Node_For_Itype (Derived_Type);
8929 and then Nkind (Def) = N_Full_Type_Declaration
8932 (Defining_Identifier (Def), Ifaces_List);
8937 -- A type extension is automatically Ghost when one of its
8938 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8939 -- also inherited when the parent type is Ghost, but this is
8940 -- done in Build_Derived_Type as the mechanism also handles
8941 -- untagged derivations.
8943 if Implements_Ghost_Interface (Derived_Type) then
8944 Set_Is_Ghost_Entity (Derived_Type);
8950 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8951 Set_Has_Non_Standard_Rep
8952 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8955 -- STEP 4: Inherit components from the parent base and constrain them.
8956 -- Apply the second transformation described in point 6. above.
8958 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8959 or else not Has_Discriminants (Parent_Type)
8960 or else not Is_Constrained (Parent_Type)
8964 Constrs := Discriminant_Constraint (Parent_Type);
8969 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8971 -- STEP 5a: Copy the parent record declaration for untagged types
8973 if not Is_Tagged then
8975 -- Discriminant_Constraint (Derived_Type) has been properly
8976 -- constructed. Save it and temporarily set it to Empty because we
8977 -- do not want the call to New_Copy_Tree below to mess this list.
8979 if Has_Discriminants (Derived_Type) then
8980 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8981 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8983 Save_Discr_Constr := No_Elist;
8986 -- Save the Etype field of Derived_Type. It is correctly set now,
8987 -- but the call to New_Copy tree may remap it to point to itself,
8988 -- which is not what we want. Ditto for the Next_Entity field.
8990 Save_Etype := Etype (Derived_Type);
8991 Save_Next_Entity := Next_Entity (Derived_Type);
8993 -- Assoc_List maps all stored discriminants in the Parent_Base to
8994 -- stored discriminants in the Derived_Type. It is fundamental that
8995 -- no types or itypes with discriminants other than the stored
8996 -- discriminants appear in the entities declared inside
8997 -- Derived_Type, since the back end cannot deal with it.
9001 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
9003 -- Restore the fields saved prior to the New_Copy_Tree call
9004 -- and compute the stored constraint.
9006 Set_Etype (Derived_Type, Save_Etype);
9007 Set_Next_Entity (Derived_Type, Save_Next_Entity);
9009 if Has_Discriminants (Derived_Type) then
9010 Set_Discriminant_Constraint
9011 (Derived_Type, Save_Discr_Constr);
9012 Set_Stored_Constraint
9013 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
9014 Replace_Components (Derived_Type, New_Decl);
9015 Set_Has_Implicit_Dereference
9016 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
9019 -- Insert the new derived type declaration
9021 Rewrite (N, New_Decl);
9023 -- STEP 5b: Complete the processing for record extensions in generics
9025 -- There is no completion for record extensions declared in the
9026 -- parameter part of a generic, so we need to complete processing for
9027 -- these generic record extensions here. The Record_Type_Definition call
9028 -- will change the Ekind of the components from E_Void to E_Component.
9030 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
9031 Record_Type_Definition (Empty, Derived_Type);
9033 -- STEP 5c: Process the record extension for non private tagged types
9035 elsif not Private_Extension then
9036 Expand_Record_Extension (Derived_Type, Type_Def);
9038 -- Note : previously in ASIS mode we set the Parent_Subtype of the
9039 -- derived type to propagate some semantic information. This led
9040 -- to other ASIS failures and has been removed.
9042 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
9043 -- implemented interfaces if we are in expansion mode
9046 and then Has_Interfaces (Derived_Type)
9048 Add_Interface_Tag_Components (N, Derived_Type);
9051 -- Analyze the record extension
9053 Record_Type_Definition
9054 (Record_Extension_Part (Type_Def), Derived_Type);
9059 -- Nothing else to do if there is an error in the derivation.
9060 -- An unusual case: the full view may be derived from a type in an
9061 -- instance, when the partial view was used illegally as an actual
9062 -- in that instance, leading to a circular definition.
9064 if Etype (Derived_Type) = Any_Type
9065 or else Etype (Parent_Type) = Derived_Type
9070 -- Set delayed freeze and then derive subprograms, we need to do
9071 -- this in this order so that derived subprograms inherit the
9072 -- derived freeze if necessary.
9074 Set_Has_Delayed_Freeze (Derived_Type);
9076 if Derive_Subps then
9077 Derive_Subprograms (Parent_Type, Derived_Type);
9080 -- If we have a private extension which defines a constrained derived
9081 -- type mark as constrained here after we have derived subprograms. See
9082 -- comment on point 9. just above the body of Build_Derived_Record_Type.
9084 if Private_Extension and then Inherit_Discrims then
9085 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
9086 Set_Is_Constrained (Derived_Type, True);
9087 Set_Discriminant_Constraint (Derived_Type, Discs);
9089 elsif Is_Constrained (Parent_Type) then
9091 (Derived_Type, True);
9092 Set_Discriminant_Constraint
9093 (Derived_Type, Discriminant_Constraint (Parent_Type));
9097 -- Update the class-wide type, which shares the now-completed entity
9098 -- list with its specific type. In case of underlying record views,
9099 -- we do not generate the corresponding class wide entity.
9102 and then not Is_Underlying_Record_View (Derived_Type)
9105 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
9107 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
9110 Check_Function_Writable_Actuals (N);
9111 end Build_Derived_Record_Type;
9113 ------------------------
9114 -- Build_Derived_Type --
9115 ------------------------
9117 procedure Build_Derived_Type
9119 Parent_Type : Entity_Id;
9120 Derived_Type : Entity_Id;
9121 Is_Completion : Boolean;
9122 Derive_Subps : Boolean := True)
9124 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
9127 -- Set common attributes
9129 Set_Scope (Derived_Type, Current_Scope);
9131 Set_Etype (Derived_Type, Parent_Base);
9132 Set_Ekind (Derived_Type, Ekind (Parent_Base));
9133 Propagate_Concurrent_Flags (Derived_Type, Parent_Base);
9135 Set_Size_Info (Derived_Type, Parent_Type);
9136 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
9137 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
9138 Set_Disable_Controlled (Derived_Type, Disable_Controlled (Parent_Type));
9140 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
9141 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
9143 if Is_Tagged_Type (Derived_Type) then
9144 Set_No_Tagged_Streams_Pragma
9145 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
9148 -- If the parent has primitive routines, set the derived type link
9150 if Has_Primitive_Operations (Parent_Type) then
9151 Set_Derived_Type_Link (Parent_Base, Derived_Type);
9154 -- If the parent type is a private subtype, the convention on the base
9155 -- type may be set in the private part, and not propagated to the
9156 -- subtype until later, so we obtain the convention from the base type.
9158 Set_Convention (Derived_Type, Convention (Parent_Base));
9160 -- Set SSO default for record or array type
9162 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
9163 and then Is_Base_Type (Derived_Type)
9165 Set_Default_SSO (Derived_Type);
9168 -- A derived type inherits the Default_Initial_Condition pragma coming
9169 -- from any parent type within the derivation chain.
9171 if Has_DIC (Parent_Type) then
9172 Set_Has_Inherited_DIC (Derived_Type);
9175 -- A derived type inherits any class-wide invariants coming from a
9176 -- parent type or an interface. Note that the invariant procedure of
9177 -- the parent type should not be inherited because the derived type may
9178 -- define invariants of its own.
9180 if not Is_Interface (Derived_Type) then
9181 if Has_Inherited_Invariants (Parent_Type)
9182 or else Has_Inheritable_Invariants (Parent_Type)
9184 Set_Has_Inherited_Invariants (Derived_Type);
9186 elsif Is_Concurrent_Type (Derived_Type)
9187 or else Is_Tagged_Type (Derived_Type)
9192 Iface_Elmt : Elmt_Id;
9197 Ifaces_List => Ifaces,
9198 Exclude_Parents => True);
9200 if Present (Ifaces) then
9201 Iface_Elmt := First_Elmt (Ifaces);
9202 while Present (Iface_Elmt) loop
9203 Iface := Node (Iface_Elmt);
9205 if Has_Inheritable_Invariants (Iface) then
9206 Set_Has_Inherited_Invariants (Derived_Type);
9210 Next_Elmt (Iface_Elmt);
9217 -- We similarly inherit predicates. Note that for scalar derived types
9218 -- the predicate is inherited from the first subtype, and not from its
9219 -- (anonymous) base type.
9221 if Has_Predicates (Parent_Type)
9222 or else Has_Predicates (First_Subtype (Parent_Type))
9224 Set_Has_Predicates (Derived_Type);
9227 -- The derived type inherits the representation clauses of the parent
9229 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
9231 -- If the parent type has delayed rep aspects, then mark the derived
9232 -- type as possibly inheriting a delayed rep aspect.
9234 if Has_Delayed_Rep_Aspects (Parent_Type) then
9235 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
9238 -- A derived type becomes Ghost when its parent type is also Ghost
9239 -- (SPARK RM 6.9(9)). Note that the Ghost-related attributes are not
9240 -- directly inherited because the Ghost policy in effect may differ.
9242 if Is_Ghost_Entity (Parent_Type) then
9243 Set_Is_Ghost_Entity (Derived_Type);
9246 -- Type dependent processing
9248 case Ekind (Parent_Type) is
9249 when Numeric_Kind =>
9250 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9253 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9255 when Class_Wide_Kind
9259 Build_Derived_Record_Type
9260 (N, Parent_Type, Derived_Type, Derive_Subps);
9263 when Enumeration_Kind =>
9264 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9267 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9269 when Incomplete_Or_Private_Kind =>
9270 Build_Derived_Private_Type
9271 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9273 -- For discriminated types, the derivation includes deriving
9274 -- primitive operations. For others it is done below.
9276 if Is_Tagged_Type (Parent_Type)
9277 or else Has_Discriminants (Parent_Type)
9278 or else (Present (Full_View (Parent_Type))
9279 and then Has_Discriminants (Full_View (Parent_Type)))
9284 when Concurrent_Kind =>
9285 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9288 raise Program_Error;
9291 -- Nothing more to do if some error occurred
9293 if Etype (Derived_Type) = Any_Type then
9297 -- Set delayed freeze and then derive subprograms, we need to do this
9298 -- in this order so that derived subprograms inherit the derived freeze
9301 Set_Has_Delayed_Freeze (Derived_Type);
9303 if Derive_Subps then
9304 Derive_Subprograms (Parent_Type, Derived_Type);
9307 Set_Has_Primitive_Operations
9308 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9309 end Build_Derived_Type;
9311 -----------------------
9312 -- Build_Discriminal --
9313 -----------------------
9315 procedure Build_Discriminal (Discrim : Entity_Id) is
9316 D_Minal : Entity_Id;
9317 CR_Disc : Entity_Id;
9320 -- A discriminal has the same name as the discriminant
9322 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9324 Set_Ekind (D_Minal, E_In_Parameter);
9325 Set_Mechanism (D_Minal, Default_Mechanism);
9326 Set_Etype (D_Minal, Etype (Discrim));
9327 Set_Scope (D_Minal, Current_Scope);
9328 Set_Parent (D_Minal, Parent (Discrim));
9330 Set_Discriminal (Discrim, D_Minal);
9331 Set_Discriminal_Link (D_Minal, Discrim);
9333 -- For task types, build at once the discriminants of the corresponding
9334 -- record, which are needed if discriminants are used in entry defaults
9335 -- and in family bounds.
9337 if Is_Concurrent_Type (Current_Scope)
9339 Is_Limited_Type (Current_Scope)
9341 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9343 Set_Ekind (CR_Disc, E_In_Parameter);
9344 Set_Mechanism (CR_Disc, Default_Mechanism);
9345 Set_Etype (CR_Disc, Etype (Discrim));
9346 Set_Scope (CR_Disc, Current_Scope);
9347 Set_Discriminal_Link (CR_Disc, Discrim);
9348 Set_CR_Discriminant (Discrim, CR_Disc);
9350 end Build_Discriminal;
9352 ------------------------------------
9353 -- Build_Discriminant_Constraints --
9354 ------------------------------------
9356 function Build_Discriminant_Constraints
9359 Derived_Def : Boolean := False) return Elist_Id
9361 C : constant Node_Id := Constraint (Def);
9362 Nb_Discr : constant Nat := Number_Discriminants (T);
9364 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9365 -- Saves the expression corresponding to a given discriminant in T
9367 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9368 -- Return the Position number within array Discr_Expr of a discriminant
9369 -- D within the discriminant list of the discriminated type T.
9371 procedure Process_Discriminant_Expression
9374 -- If this is a discriminant constraint on a partial view, do not
9375 -- generate an overflow check on the discriminant expression. The check
9376 -- will be generated when constraining the full view. Otherwise the
9377 -- backend creates duplicate symbols for the temporaries corresponding
9378 -- to the expressions to be checked, causing spurious assembler errors.
9384 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9388 Disc := First_Discriminant (T);
9389 for J in Discr_Expr'Range loop
9394 Next_Discriminant (Disc);
9397 -- Note: Since this function is called on discriminants that are
9398 -- known to belong to the discriminated type, falling through the
9399 -- loop with no match signals an internal compiler error.
9401 raise Program_Error;
9404 -------------------------------------
9405 -- Process_Discriminant_Expression --
9406 -------------------------------------
9408 procedure Process_Discriminant_Expression
9412 BDT : constant Entity_Id := Base_Type (Etype (D));
9415 -- If this is a discriminant constraint on a partial view, do
9416 -- not generate an overflow on the discriminant expression. The
9417 -- check will be generated when constraining the full view.
9419 if Is_Private_Type (T)
9420 and then Present (Full_View (T))
9422 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9424 Analyze_And_Resolve (Expr, BDT);
9426 end Process_Discriminant_Expression;
9428 -- Declarations local to Build_Discriminant_Constraints
9432 Elist : constant Elist_Id := New_Elmt_List;
9440 Discrim_Present : Boolean := False;
9442 -- Start of processing for Build_Discriminant_Constraints
9445 -- The following loop will process positional associations only.
9446 -- For a positional association, the (single) discriminant is
9447 -- implicitly specified by position, in textual order (RM 3.7.2).
9449 Discr := First_Discriminant (T);
9450 Constr := First (Constraints (C));
9451 for D in Discr_Expr'Range loop
9452 exit when Nkind (Constr) = N_Discriminant_Association;
9455 Error_Msg_N ("too few discriminants given in constraint", C);
9456 return New_Elmt_List;
9458 elsif Nkind (Constr) = N_Range
9459 or else (Nkind (Constr) = N_Attribute_Reference
9460 and then Attribute_Name (Constr) = Name_Range)
9463 ("a range is not a valid discriminant constraint", Constr);
9464 Discr_Expr (D) := Error;
9467 Process_Discriminant_Expression (Constr, Discr);
9468 Discr_Expr (D) := Constr;
9471 Next_Discriminant (Discr);
9475 if No (Discr) and then Present (Constr) then
9476 Error_Msg_N ("too many discriminants given in constraint", Constr);
9477 return New_Elmt_List;
9480 -- Named associations can be given in any order, but if both positional
9481 -- and named associations are used in the same discriminant constraint,
9482 -- then positional associations must occur first, at their normal
9483 -- position. Hence once a named association is used, the rest of the
9484 -- discriminant constraint must use only named associations.
9486 while Present (Constr) loop
9488 -- Positional association forbidden after a named association
9490 if Nkind (Constr) /= N_Discriminant_Association then
9491 Error_Msg_N ("positional association follows named one", Constr);
9492 return New_Elmt_List;
9494 -- Otherwise it is a named association
9497 -- E records the type of the discriminants in the named
9498 -- association. All the discriminants specified in the same name
9499 -- association must have the same type.
9503 -- Search the list of discriminants in T to see if the simple name
9504 -- given in the constraint matches any of them.
9506 Id := First (Selector_Names (Constr));
9507 while Present (Id) loop
9510 -- If Original_Discriminant is present, we are processing a
9511 -- generic instantiation and this is an instance node. We need
9512 -- to find the name of the corresponding discriminant in the
9513 -- actual record type T and not the name of the discriminant in
9514 -- the generic formal. Example:
9517 -- type G (D : int) is private;
9519 -- subtype W is G (D => 1);
9521 -- type Rec (X : int) is record ... end record;
9522 -- package Q is new P (G => Rec);
9524 -- At the point of the instantiation, formal type G is Rec
9525 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9526 -- which really looks like "subtype W is Rec (D => 1);" at
9527 -- the point of instantiation, we want to find the discriminant
9528 -- that corresponds to D in Rec, i.e. X.
9530 if Present (Original_Discriminant (Id))
9531 and then In_Instance
9533 Discr := Find_Corresponding_Discriminant (Id, T);
9537 Discr := First_Discriminant (T);
9538 while Present (Discr) loop
9539 if Chars (Discr) = Chars (Id) then
9544 Next_Discriminant (Discr);
9548 Error_Msg_N ("& does not match any discriminant", Id);
9549 return New_Elmt_List;
9551 -- If the parent type is a generic formal, preserve the
9552 -- name of the discriminant for subsequent instances.
9553 -- see comment at the beginning of this if statement.
9555 elsif Is_Generic_Type (Root_Type (T)) then
9556 Set_Original_Discriminant (Id, Discr);
9560 Position := Pos_Of_Discr (T, Discr);
9562 if Present (Discr_Expr (Position)) then
9563 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9566 -- Each discriminant specified in the same named association
9567 -- must be associated with a separate copy of the
9568 -- corresponding expression.
9570 if Present (Next (Id)) then
9571 Expr := New_Copy_Tree (Expression (Constr));
9572 Set_Parent (Expr, Parent (Expression (Constr)));
9574 Expr := Expression (Constr);
9577 Discr_Expr (Position) := Expr;
9578 Process_Discriminant_Expression (Expr, Discr);
9581 -- A discriminant association with more than one discriminant
9582 -- name is only allowed if the named discriminants are all of
9583 -- the same type (RM 3.7.1(8)).
9586 E := Base_Type (Etype (Discr));
9588 elsif Base_Type (Etype (Discr)) /= E then
9590 ("all discriminants in an association " &
9591 "must have the same type", Id);
9601 -- A discriminant constraint must provide exactly one value for each
9602 -- discriminant of the type (RM 3.7.1(8)).
9604 for J in Discr_Expr'Range loop
9605 if No (Discr_Expr (J)) then
9606 Error_Msg_N ("too few discriminants given in constraint", C);
9607 return New_Elmt_List;
9611 -- Determine if there are discriminant expressions in the constraint
9613 for J in Discr_Expr'Range loop
9614 if Denotes_Discriminant
9615 (Discr_Expr (J), Check_Concurrent => True)
9617 Discrim_Present := True;
9621 -- Build an element list consisting of the expressions given in the
9622 -- discriminant constraint and apply the appropriate checks. The list
9623 -- is constructed after resolving any named discriminant associations
9624 -- and therefore the expressions appear in the textual order of the
9627 Discr := First_Discriminant (T);
9628 for J in Discr_Expr'Range loop
9629 if Discr_Expr (J) /= Error then
9630 Append_Elmt (Discr_Expr (J), Elist);
9632 -- If any of the discriminant constraints is given by a
9633 -- discriminant and we are in a derived type declaration we
9634 -- have a discriminant renaming. Establish link between new
9635 -- and old discriminant.
9637 if Denotes_Discriminant (Discr_Expr (J)) then
9639 Set_Corresponding_Discriminant
9640 (Entity (Discr_Expr (J)), Discr);
9643 -- Force the evaluation of non-discriminant expressions.
9644 -- If we have found a discriminant in the constraint 3.4(26)
9645 -- and 3.8(18) demand that no range checks are performed are
9646 -- after evaluation. If the constraint is for a component
9647 -- definition that has a per-object constraint, expressions are
9648 -- evaluated but not checked either. In all other cases perform
9652 if Discrim_Present then
9655 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9657 Has_Per_Object_Constraint
9658 (Defining_Identifier (Parent (Parent (Def))))
9662 elsif Is_Access_Type (Etype (Discr)) then
9663 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9666 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9669 Force_Evaluation (Discr_Expr (J));
9672 -- Check that the designated type of an access discriminant's
9673 -- expression is not a class-wide type unless the discriminant's
9674 -- designated type is also class-wide.
9676 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9677 and then not Is_Class_Wide_Type
9678 (Designated_Type (Etype (Discr)))
9679 and then Etype (Discr_Expr (J)) /= Any_Type
9680 and then Is_Class_Wide_Type
9681 (Designated_Type (Etype (Discr_Expr (J))))
9683 Wrong_Type (Discr_Expr (J), Etype (Discr));
9685 elsif Is_Access_Type (Etype (Discr))
9686 and then not Is_Access_Constant (Etype (Discr))
9687 and then Is_Access_Type (Etype (Discr_Expr (J)))
9688 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9691 ("constraint for discriminant& must be access to variable",
9696 Next_Discriminant (Discr);
9700 end Build_Discriminant_Constraints;
9702 ---------------------------------
9703 -- Build_Discriminated_Subtype --
9704 ---------------------------------
9706 procedure Build_Discriminated_Subtype
9710 Related_Nod : Node_Id;
9711 For_Access : Boolean := False)
9713 Has_Discrs : constant Boolean := Has_Discriminants (T);
9714 Constrained : constant Boolean :=
9716 and then not Is_Empty_Elmt_List (Elist)
9717 and then not Is_Class_Wide_Type (T))
9718 or else Is_Constrained (T);
9721 if Ekind (T) = E_Record_Type then
9723 Set_Ekind (Def_Id, E_Private_Subtype);
9724 Set_Is_For_Access_Subtype (Def_Id, True);
9726 Set_Ekind (Def_Id, E_Record_Subtype);
9729 -- Inherit preelaboration flag from base, for types for which it
9730 -- may have been set: records, private types, protected types.
9732 Set_Known_To_Have_Preelab_Init
9733 (Def_Id, Known_To_Have_Preelab_Init (T));
9735 elsif Ekind (T) = E_Task_Type then
9736 Set_Ekind (Def_Id, E_Task_Subtype);
9738 elsif Ekind (T) = E_Protected_Type then
9739 Set_Ekind (Def_Id, E_Protected_Subtype);
9740 Set_Known_To_Have_Preelab_Init
9741 (Def_Id, Known_To_Have_Preelab_Init (T));
9743 elsif Is_Private_Type (T) then
9744 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9745 Set_Known_To_Have_Preelab_Init
9746 (Def_Id, Known_To_Have_Preelab_Init (T));
9748 -- Private subtypes may have private dependents
9750 Set_Private_Dependents (Def_Id, New_Elmt_List);
9752 elsif Is_Class_Wide_Type (T) then
9753 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9756 -- Incomplete type. Attach subtype to list of dependents, to be
9757 -- completed with full view of parent type, unless is it the
9758 -- designated subtype of a record component within an init_proc.
9759 -- This last case arises for a component of an access type whose
9760 -- designated type is incomplete (e.g. a Taft Amendment type).
9761 -- The designated subtype is within an inner scope, and needs no
9762 -- elaboration, because only the access type is needed in the
9763 -- initialization procedure.
9765 Set_Ekind (Def_Id, Ekind (T));
9767 if For_Access and then Within_Init_Proc then
9770 Append_Elmt (Def_Id, Private_Dependents (T));
9774 Set_Etype (Def_Id, T);
9775 Init_Size_Align (Def_Id);
9776 Set_Has_Discriminants (Def_Id, Has_Discrs);
9777 Set_Is_Constrained (Def_Id, Constrained);
9779 Set_First_Entity (Def_Id, First_Entity (T));
9780 Set_Last_Entity (Def_Id, Last_Entity (T));
9781 Set_Has_Implicit_Dereference
9782 (Def_Id, Has_Implicit_Dereference (T));
9784 -- If the subtype is the completion of a private declaration, there may
9785 -- have been representation clauses for the partial view, and they must
9786 -- be preserved. Build_Derived_Type chains the inherited clauses with
9787 -- the ones appearing on the extension. If this comes from a subtype
9788 -- declaration, all clauses are inherited.
9790 if No (First_Rep_Item (Def_Id)) then
9791 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9794 if Is_Tagged_Type (T) then
9795 Set_Is_Tagged_Type (Def_Id);
9796 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9797 Make_Class_Wide_Type (Def_Id);
9800 Set_Stored_Constraint (Def_Id, No_Elist);
9803 Set_Discriminant_Constraint (Def_Id, Elist);
9804 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9807 if Is_Tagged_Type (T) then
9809 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9810 -- concurrent record type (which has the list of primitive
9813 if Ada_Version >= Ada_2005
9814 and then Is_Concurrent_Type (T)
9816 Set_Corresponding_Record_Type (Def_Id,
9817 Corresponding_Record_Type (T));
9819 Set_Direct_Primitive_Operations (Def_Id,
9820 Direct_Primitive_Operations (T));
9823 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9826 -- Subtypes introduced by component declarations do not need to be
9827 -- marked as delayed, and do not get freeze nodes, because the semantics
9828 -- verifies that the parents of the subtypes are frozen before the
9829 -- enclosing record is frozen.
9831 if not Is_Type (Scope (Def_Id)) then
9832 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9834 if Is_Private_Type (T)
9835 and then Present (Full_View (T))
9837 Conditional_Delay (Def_Id, Full_View (T));
9839 Conditional_Delay (Def_Id, T);
9843 if Is_Record_Type (T) then
9844 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9847 and then not Is_Empty_Elmt_List (Elist)
9848 and then not For_Access
9850 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9851 elsif not For_Access then
9852 Set_Cloned_Subtype (Def_Id, T);
9855 end Build_Discriminated_Subtype;
9857 ---------------------------
9858 -- Build_Itype_Reference --
9859 ---------------------------
9861 procedure Build_Itype_Reference
9865 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9868 -- Itype references are only created for use by the back-end
9870 if Inside_A_Generic then
9873 Set_Itype (IR, Ityp);
9874 Insert_After (Nod, IR);
9876 end Build_Itype_Reference;
9878 ------------------------
9879 -- Build_Scalar_Bound --
9880 ------------------------
9882 function Build_Scalar_Bound
9885 Der_T : Entity_Id) return Node_Id
9887 New_Bound : Entity_Id;
9890 -- Note: not clear why this is needed, how can the original bound
9891 -- be unanalyzed at this point? and if it is, what business do we
9892 -- have messing around with it? and why is the base type of the
9893 -- parent type the right type for the resolution. It probably is
9894 -- not. It is OK for the new bound we are creating, but not for
9895 -- the old one??? Still if it never happens, no problem.
9897 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9899 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9900 New_Bound := New_Copy (Bound);
9901 Set_Etype (New_Bound, Der_T);
9902 Set_Analyzed (New_Bound);
9904 elsif Is_Entity_Name (Bound) then
9905 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9907 -- The following is almost certainly wrong. What business do we have
9908 -- relocating a node (Bound) that is presumably still attached to
9909 -- the tree elsewhere???
9912 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9915 Set_Etype (New_Bound, Der_T);
9917 end Build_Scalar_Bound;
9919 --------------------------------
9920 -- Build_Underlying_Full_View --
9921 --------------------------------
9923 procedure Build_Underlying_Full_View
9928 Loc : constant Source_Ptr := Sloc (N);
9929 Subt : constant Entity_Id :=
9930 Make_Defining_Identifier
9931 (Loc, New_External_Name (Chars (Typ), 'S'));
9938 procedure Set_Discriminant_Name (Id : Node_Id);
9939 -- If the derived type has discriminants, they may rename discriminants
9940 -- of the parent. When building the full view of the parent, we need to
9941 -- recover the names of the original discriminants if the constraint is
9942 -- given by named associations.
9944 ---------------------------
9945 -- Set_Discriminant_Name --
9946 ---------------------------
9948 procedure Set_Discriminant_Name (Id : Node_Id) is
9952 Set_Original_Discriminant (Id, Empty);
9954 if Has_Discriminants (Typ) then
9955 Disc := First_Discriminant (Typ);
9956 while Present (Disc) loop
9957 if Chars (Disc) = Chars (Id)
9958 and then Present (Corresponding_Discriminant (Disc))
9960 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9962 Next_Discriminant (Disc);
9965 end Set_Discriminant_Name;
9967 -- Start of processing for Build_Underlying_Full_View
9970 if Nkind (N) = N_Full_Type_Declaration then
9971 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9973 elsif Nkind (N) = N_Subtype_Declaration then
9974 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9976 elsif Nkind (N) = N_Component_Declaration then
9979 (Constraint (Subtype_Indication (Component_Definition (N))));
9982 raise Program_Error;
9985 C := First (Constraints (Constr));
9986 while Present (C) loop
9987 if Nkind (C) = N_Discriminant_Association then
9988 Id := First (Selector_Names (C));
9989 while Present (Id) loop
9990 Set_Discriminant_Name (Id);
9999 Make_Subtype_Declaration (Loc,
10000 Defining_Identifier => Subt,
10001 Subtype_Indication =>
10002 Make_Subtype_Indication (Loc,
10003 Subtype_Mark => New_Occurrence_Of (Par, Loc),
10004 Constraint => New_Copy_Tree (Constr)));
10006 -- If this is a component subtype for an outer itype, it is not
10007 -- a list member, so simply set the parent link for analysis: if
10008 -- the enclosing type does not need to be in a declarative list,
10009 -- neither do the components.
10011 if Is_List_Member (N)
10012 and then Nkind (N) /= N_Component_Declaration
10014 Insert_Before (N, Indic);
10016 Set_Parent (Indic, Parent (N));
10020 Set_Underlying_Full_View (Typ, Full_View (Subt));
10021 end Build_Underlying_Full_View;
10023 -------------------------------
10024 -- Check_Abstract_Overriding --
10025 -------------------------------
10027 procedure Check_Abstract_Overriding (T : Entity_Id) is
10028 Alias_Subp : Entity_Id;
10030 Op_List : Elist_Id;
10032 Type_Def : Node_Id;
10034 procedure Check_Pragma_Implemented (Subp : Entity_Id);
10035 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
10036 -- which has pragma Implemented already set. Check whether Subp's entity
10037 -- kind conforms to the implementation kind of the overridden routine.
10039 procedure Check_Pragma_Implemented
10041 Iface_Subp : Entity_Id);
10042 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
10043 -- Iface_Subp and both entities have pragma Implemented already set on
10044 -- them. Check whether the two implementation kinds are conforming.
10046 procedure Inherit_Pragma_Implemented
10048 Iface_Subp : Entity_Id);
10049 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
10050 -- subprogram Iface_Subp which has been marked by pragma Implemented.
10051 -- Propagate the implementation kind of Iface_Subp to Subp.
10053 ------------------------------
10054 -- Check_Pragma_Implemented --
10055 ------------------------------
10057 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
10058 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
10059 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
10060 Subp_Alias : constant Entity_Id := Alias (Subp);
10061 Contr_Typ : Entity_Id;
10062 Impl_Subp : Entity_Id;
10065 -- Subp must have an alias since it is a hidden entity used to link
10066 -- an interface subprogram to its overriding counterpart.
10068 pragma Assert (Present (Subp_Alias));
10070 -- Handle aliases to synchronized wrappers
10072 Impl_Subp := Subp_Alias;
10074 if Is_Primitive_Wrapper (Impl_Subp) then
10075 Impl_Subp := Wrapped_Entity (Impl_Subp);
10078 -- Extract the type of the controlling formal
10080 Contr_Typ := Etype (First_Formal (Subp_Alias));
10082 if Is_Concurrent_Record_Type (Contr_Typ) then
10083 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
10086 -- An interface subprogram whose implementation kind is By_Entry must
10087 -- be implemented by an entry.
10089 if Impl_Kind = Name_By_Entry
10090 and then Ekind (Impl_Subp) /= E_Entry
10092 Error_Msg_Node_2 := Iface_Alias;
10094 ("type & must implement abstract subprogram & with an entry",
10095 Subp_Alias, Contr_Typ);
10097 elsif Impl_Kind = Name_By_Protected_Procedure then
10099 -- An interface subprogram whose implementation kind is By_
10100 -- Protected_Procedure cannot be implemented by a primitive
10101 -- procedure of a task type.
10103 if Ekind (Contr_Typ) /= E_Protected_Type then
10104 Error_Msg_Node_2 := Contr_Typ;
10106 ("interface subprogram & cannot be implemented by a " &
10107 "primitive procedure of task type &", Subp_Alias,
10110 -- An interface subprogram whose implementation kind is By_
10111 -- Protected_Procedure must be implemented by a procedure.
10113 elsif Ekind (Impl_Subp) /= E_Procedure then
10114 Error_Msg_Node_2 := Iface_Alias;
10116 ("type & must implement abstract subprogram & with a " &
10117 "procedure", Subp_Alias, Contr_Typ);
10119 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10120 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10122 Error_Msg_Name_1 := Impl_Kind;
10124 ("overriding operation& must have synchronization%",
10128 -- If primitive has Optional synchronization, overriding operation
10129 -- must match if it has an explicit synchronization..
10131 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
10132 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
10134 Error_Msg_Name_1 := Impl_Kind;
10136 ("overriding operation& must have syncrhonization%",
10139 end Check_Pragma_Implemented;
10141 ------------------------------
10142 -- Check_Pragma_Implemented --
10143 ------------------------------
10145 procedure Check_Pragma_Implemented
10147 Iface_Subp : Entity_Id)
10149 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10150 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
10153 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
10154 -- and overriding subprogram are different. In general this is an
10155 -- error except when the implementation kind of the overridden
10156 -- subprograms is By_Any or Optional.
10158 if Iface_Kind /= Subp_Kind
10159 and then Iface_Kind /= Name_By_Any
10160 and then Iface_Kind /= Name_Optional
10162 if Iface_Kind = Name_By_Entry then
10164 ("incompatible implementation kind, overridden subprogram " &
10165 "is marked By_Entry", Subp);
10168 ("incompatible implementation kind, overridden subprogram " &
10169 "is marked By_Protected_Procedure", Subp);
10172 end Check_Pragma_Implemented;
10174 --------------------------------
10175 -- Inherit_Pragma_Implemented --
10176 --------------------------------
10178 procedure Inherit_Pragma_Implemented
10180 Iface_Subp : Entity_Id)
10182 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
10183 Loc : constant Source_Ptr := Sloc (Subp);
10184 Impl_Prag : Node_Id;
10187 -- Since the implementation kind is stored as a representation item
10188 -- rather than a flag, create a pragma node.
10192 Chars => Name_Implemented,
10193 Pragma_Argument_Associations => New_List (
10194 Make_Pragma_Argument_Association (Loc,
10195 Expression => New_Occurrence_Of (Subp, Loc)),
10197 Make_Pragma_Argument_Association (Loc,
10198 Expression => Make_Identifier (Loc, Iface_Kind))));
10200 -- The pragma doesn't need to be analyzed because it is internally
10201 -- built. It is safe to directly register it as a rep item since we
10202 -- are only interested in the characters of the implementation kind.
10204 Record_Rep_Item (Subp, Impl_Prag);
10205 end Inherit_Pragma_Implemented;
10207 -- Start of processing for Check_Abstract_Overriding
10210 Op_List := Primitive_Operations (T);
10212 -- Loop to check primitive operations
10214 Elmt := First_Elmt (Op_List);
10215 while Present (Elmt) loop
10216 Subp := Node (Elmt);
10217 Alias_Subp := Alias (Subp);
10219 -- Inherited subprograms are identified by the fact that they do not
10220 -- come from source, and the associated source location is the
10221 -- location of the first subtype of the derived type.
10223 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
10224 -- subprograms that "require overriding".
10226 -- Special exception, do not complain about failure to override the
10227 -- stream routines _Input and _Output, as well as the primitive
10228 -- operations used in dispatching selects since we always provide
10229 -- automatic overridings for these subprograms.
10231 -- The partial view of T may have been a private extension, for
10232 -- which inherited functions dispatching on result are abstract.
10233 -- If the full view is a null extension, there is no need for
10234 -- overriding in Ada 2005, but wrappers need to be built for them
10235 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
10237 if Is_Null_Extension (T)
10238 and then Has_Controlling_Result (Subp)
10239 and then Ada_Version >= Ada_2005
10240 and then Present (Alias_Subp)
10241 and then not Comes_From_Source (Subp)
10242 and then not Is_Abstract_Subprogram (Alias_Subp)
10243 and then not Is_Access_Type (Etype (Subp))
10247 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10248 -- processing because this check is done with the aliased
10251 elsif Present (Interface_Alias (Subp)) then
10254 elsif (Is_Abstract_Subprogram (Subp)
10255 or else Requires_Overriding (Subp)
10257 (Has_Controlling_Result (Subp)
10258 and then Present (Alias_Subp)
10259 and then not Comes_From_Source (Subp)
10260 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10261 and then not Is_TSS (Subp, TSS_Stream_Input)
10262 and then not Is_TSS (Subp, TSS_Stream_Output)
10263 and then not Is_Abstract_Type (T)
10264 and then not Is_Predefined_Interface_Primitive (Subp)
10266 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10267 -- with abstract interface types because the check will be done
10268 -- with the aliased entity (otherwise we generate a duplicated
10271 and then not Present (Interface_Alias (Subp))
10273 if Present (Alias_Subp) then
10275 -- Only perform the check for a derived subprogram when the
10276 -- type has an explicit record extension. This avoids incorrect
10277 -- flagging of abstract subprograms for the case of a type
10278 -- without an extension that is derived from a formal type
10279 -- with a tagged actual (can occur within a private part).
10281 -- Ada 2005 (AI-391): In the case of an inherited function with
10282 -- a controlling result of the type, the rule does not apply if
10283 -- the type is a null extension (unless the parent function
10284 -- itself is abstract, in which case the function must still be
10285 -- be overridden). The expander will generate an overriding
10286 -- wrapper function calling the parent subprogram (see
10287 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10289 Type_Def := Type_Definition (Parent (T));
10291 if Nkind (Type_Def) = N_Derived_Type_Definition
10292 and then Present (Record_Extension_Part (Type_Def))
10294 (Ada_Version < Ada_2005
10295 or else not Is_Null_Extension (T)
10296 or else Ekind (Subp) = E_Procedure
10297 or else not Has_Controlling_Result (Subp)
10298 or else Is_Abstract_Subprogram (Alias_Subp)
10299 or else Requires_Overriding (Subp)
10300 or else Is_Access_Type (Etype (Subp)))
10302 -- Avoid reporting error in case of abstract predefined
10303 -- primitive inherited from interface type because the
10304 -- body of internally generated predefined primitives
10305 -- of tagged types are generated later by Freeze_Type
10307 if Is_Interface (Root_Type (T))
10308 and then Is_Abstract_Subprogram (Subp)
10309 and then Is_Predefined_Dispatching_Operation (Subp)
10310 and then not Comes_From_Source (Ultimate_Alias (Subp))
10314 -- A null extension is not obliged to override an inherited
10315 -- procedure subject to pragma Extensions_Visible with value
10316 -- False and at least one controlling OUT parameter
10317 -- (SPARK RM 6.1.7(6)).
10319 elsif Is_Null_Extension (T)
10320 and then Is_EVF_Procedure (Subp)
10326 ("type must be declared abstract or & overridden",
10329 -- Traverse the whole chain of aliased subprograms to
10330 -- complete the error notification. This is especially
10331 -- useful for traceability of the chain of entities when
10332 -- the subprogram corresponds with an interface
10333 -- subprogram (which may be defined in another package).
10335 if Present (Alias_Subp) then
10341 while Present (Alias (E)) loop
10343 -- Avoid reporting redundant errors on entities
10344 -- inherited from interfaces
10346 if Sloc (E) /= Sloc (T) then
10347 Error_Msg_Sloc := Sloc (E);
10349 ("\& has been inherited #", T, Subp);
10355 Error_Msg_Sloc := Sloc (E);
10357 -- AI05-0068: report if there is an overriding
10358 -- non-abstract subprogram that is invisible.
10361 and then not Is_Abstract_Subprogram (E)
10364 ("\& subprogram# is not visible",
10367 -- Clarify the case where a non-null extension must
10368 -- override inherited procedure subject to pragma
10369 -- Extensions_Visible with value False and at least
10370 -- one controlling OUT param.
10372 elsif Is_EVF_Procedure (E) then
10374 ("\& # is subject to Extensions_Visible False",
10379 ("\& has been inherited from subprogram #",
10386 -- Ada 2005 (AI-345): Protected or task type implementing
10387 -- abstract interfaces.
10389 elsif Is_Concurrent_Record_Type (T)
10390 and then Present (Interfaces (T))
10392 -- There is no need to check here RM 9.4(11.9/3) since we
10393 -- are processing the corresponding record type and the
10394 -- mode of the overriding subprograms was verified by
10395 -- Check_Conformance when the corresponding concurrent
10396 -- type declaration was analyzed.
10399 ("interface subprogram & must be overridden", T, Subp);
10401 -- Examine primitive operations of synchronized type to find
10402 -- homonyms that have the wrong profile.
10408 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10409 while Present (Prim) loop
10410 if Chars (Prim) = Chars (Subp) then
10412 ("profile is not type conformant with prefixed "
10413 & "view profile of inherited operation&",
10417 Next_Entity (Prim);
10423 Error_Msg_Node_2 := T;
10425 ("abstract subprogram& not allowed for type&", Subp);
10427 -- Also post unconditional warning on the type (unconditional
10428 -- so that if there are more than one of these cases, we get
10429 -- them all, and not just the first one).
10431 Error_Msg_Node_2 := Subp;
10432 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10435 -- A subprogram subject to pragma Extensions_Visible with value
10436 -- "True" cannot override a subprogram subject to the same pragma
10437 -- with value "False" (SPARK RM 6.1.7(5)).
10439 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10440 and then Present (Overridden_Operation (Subp))
10441 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10442 Extensions_Visible_False
10444 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10446 ("subprogram & with Extensions_Visible True cannot override "
10447 & "subprogram # with Extensions_Visible False", Subp);
10450 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10452 -- Subp is an expander-generated procedure which maps an interface
10453 -- alias to a protected wrapper. The interface alias is flagged by
10454 -- pragma Implemented. Ensure that Subp is a procedure when the
10455 -- implementation kind is By_Protected_Procedure or an entry when
10458 if Ada_Version >= Ada_2012
10459 and then Is_Hidden (Subp)
10460 and then Present (Interface_Alias (Subp))
10461 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10463 Check_Pragma_Implemented (Subp);
10466 -- Subp is an interface primitive which overrides another interface
10467 -- primitive marked with pragma Implemented.
10469 if Ada_Version >= Ada_2012
10470 and then Present (Overridden_Operation (Subp))
10471 and then Has_Rep_Pragma
10472 (Overridden_Operation (Subp), Name_Implemented)
10474 -- If the overriding routine is also marked by Implemented, check
10475 -- that the two implementation kinds are conforming.
10477 if Has_Rep_Pragma (Subp, Name_Implemented) then
10478 Check_Pragma_Implemented
10480 Iface_Subp => Overridden_Operation (Subp));
10482 -- Otherwise the overriding routine inherits the implementation
10483 -- kind from the overridden subprogram.
10486 Inherit_Pragma_Implemented
10488 Iface_Subp => Overridden_Operation (Subp));
10492 -- If the operation is a wrapper for a synchronized primitive, it
10493 -- may be called indirectly through a dispatching select. We assume
10494 -- that it will be referenced elsewhere indirectly, and suppress
10495 -- warnings about an unused entity.
10497 if Is_Primitive_Wrapper (Subp)
10498 and then Present (Wrapped_Entity (Subp))
10500 Set_Referenced (Wrapped_Entity (Subp));
10505 end Check_Abstract_Overriding;
10507 ------------------------------------------------
10508 -- Check_Access_Discriminant_Requires_Limited --
10509 ------------------------------------------------
10511 procedure Check_Access_Discriminant_Requires_Limited
10516 -- A discriminant_specification for an access discriminant shall appear
10517 -- only in the declaration for a task or protected type, or for a type
10518 -- with the reserved word 'limited' in its definition or in one of its
10519 -- ancestors (RM 3.7(10)).
10521 -- AI-0063: The proper condition is that type must be immutably limited,
10522 -- or else be a partial view.
10524 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10525 if Is_Limited_View (Current_Scope)
10527 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10528 and then Limited_Present (Parent (Current_Scope)))
10534 ("access discriminants allowed only for limited types", Loc);
10537 end Check_Access_Discriminant_Requires_Limited;
10539 -----------------------------------
10540 -- Check_Aliased_Component_Types --
10541 -----------------------------------
10543 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10547 -- ??? Also need to check components of record extensions, but not
10548 -- components of protected types (which are always limited).
10550 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10551 -- types to be unconstrained. This is safe because it is illegal to
10552 -- create access subtypes to such types with explicit discriminant
10555 if not Is_Limited_Type (T) then
10556 if Ekind (T) = E_Record_Type then
10557 C := First_Component (T);
10558 while Present (C) loop
10560 and then Has_Discriminants (Etype (C))
10561 and then not Is_Constrained (Etype (C))
10562 and then not In_Instance_Body
10563 and then Ada_Version < Ada_2005
10566 ("aliased component must be constrained (RM 3.6(11))",
10570 Next_Component (C);
10573 elsif Ekind (T) = E_Array_Type then
10574 if Has_Aliased_Components (T)
10575 and then Has_Discriminants (Component_Type (T))
10576 and then not Is_Constrained (Component_Type (T))
10577 and then not In_Instance_Body
10578 and then Ada_Version < Ada_2005
10581 ("aliased component type must be constrained (RM 3.6(11))",
10586 end Check_Aliased_Component_Types;
10588 ---------------------------------------
10589 -- Check_Anonymous_Access_Components --
10590 ---------------------------------------
10592 procedure Check_Anonymous_Access_Components
10593 (Typ_Decl : Node_Id;
10596 Comp_List : Node_Id)
10598 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10599 Anon_Access : Entity_Id;
10602 Comp_Def : Node_Id;
10604 Type_Def : Node_Id;
10606 procedure Build_Incomplete_Type_Declaration;
10607 -- If the record type contains components that include an access to the
10608 -- current record, then create an incomplete type declaration for the
10609 -- record, to be used as the designated type of the anonymous access.
10610 -- This is done only once, and only if there is no previous partial
10611 -- view of the type.
10613 function Designates_T (Subt : Node_Id) return Boolean;
10614 -- Check whether a node designates the enclosing record type, or 'Class
10617 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10618 -- Check whether an access definition includes a reference to
10619 -- the enclosing record type. The reference can be a subtype mark
10620 -- in the access definition itself, a 'Class attribute reference, or
10621 -- recursively a reference appearing in a parameter specification
10622 -- or result definition of an access_to_subprogram definition.
10624 --------------------------------------
10625 -- Build_Incomplete_Type_Declaration --
10626 --------------------------------------
10628 procedure Build_Incomplete_Type_Declaration is
10633 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10634 -- it's "is new ... with record" or else "is tagged record ...".
10636 Is_Tagged : constant Boolean :=
10637 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10639 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10641 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10642 and then Tagged_Present (Type_Definition (Typ_Decl)));
10645 -- If there is a previous partial view, no need to create a new one
10646 -- If the partial view, given by Prev, is incomplete, If Prev is
10647 -- a private declaration, full declaration is flagged accordingly.
10649 if Prev /= Typ then
10651 Make_Class_Wide_Type (Prev);
10652 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10653 Set_Etype (Class_Wide_Type (Typ), Typ);
10658 elsif Has_Private_Declaration (Typ) then
10660 -- If we refer to T'Class inside T, and T is the completion of a
10661 -- private type, then make sure the class-wide type exists.
10664 Make_Class_Wide_Type (Typ);
10669 -- If there was a previous anonymous access type, the incomplete
10670 -- type declaration will have been created already.
10672 elsif Present (Current_Entity (Typ))
10673 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10674 and then Full_View (Current_Entity (Typ)) = Typ
10677 and then Comes_From_Source (Current_Entity (Typ))
10678 and then not Is_Tagged_Type (Current_Entity (Typ))
10680 Make_Class_Wide_Type (Typ);
10682 ("incomplete view of tagged type should be declared tagged??",
10683 Parent (Current_Entity (Typ)));
10688 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10689 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10691 -- Type has already been inserted into the current scope. Remove
10692 -- it, and add incomplete declaration for type, so that subsequent
10693 -- anonymous access types can use it. The entity is unchained from
10694 -- the homonym list and from immediate visibility. After analysis,
10695 -- the entity in the incomplete declaration becomes immediately
10696 -- visible in the record declaration that follows.
10698 H := Current_Entity (Typ);
10701 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10704 and then Homonym (H) /= Typ
10706 H := Homonym (Typ);
10709 Set_Homonym (H, Homonym (Typ));
10712 Insert_Before (Typ_Decl, Decl);
10714 Set_Full_View (Inc_T, Typ);
10718 -- Create a common class-wide type for both views, and set the
10719 -- Etype of the class-wide type to the full view.
10721 Make_Class_Wide_Type (Inc_T);
10722 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10723 Set_Etype (Class_Wide_Type (Typ), Typ);
10726 end Build_Incomplete_Type_Declaration;
10732 function Designates_T (Subt : Node_Id) return Boolean is
10733 Type_Id : constant Name_Id := Chars (Typ);
10735 function Names_T (Nam : Node_Id) return Boolean;
10736 -- The record type has not been introduced in the current scope
10737 -- yet, so we must examine the name of the type itself, either
10738 -- an identifier T, or an expanded name of the form P.T, where
10739 -- P denotes the current scope.
10745 function Names_T (Nam : Node_Id) return Boolean is
10747 if Nkind (Nam) = N_Identifier then
10748 return Chars (Nam) = Type_Id;
10750 elsif Nkind (Nam) = N_Selected_Component then
10751 if Chars (Selector_Name (Nam)) = Type_Id then
10752 if Nkind (Prefix (Nam)) = N_Identifier then
10753 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10755 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10756 return Chars (Selector_Name (Prefix (Nam))) =
10757 Chars (Current_Scope);
10771 -- Start of processing for Designates_T
10774 if Nkind (Subt) = N_Identifier then
10775 return Chars (Subt) = Type_Id;
10777 -- Reference can be through an expanded name which has not been
10778 -- analyzed yet, and which designates enclosing scopes.
10780 elsif Nkind (Subt) = N_Selected_Component then
10781 if Names_T (Subt) then
10784 -- Otherwise it must denote an entity that is already visible.
10785 -- The access definition may name a subtype of the enclosing
10786 -- type, if there is a previous incomplete declaration for it.
10789 Find_Selected_Component (Subt);
10791 Is_Entity_Name (Subt)
10792 and then Scope (Entity (Subt)) = Current_Scope
10794 (Chars (Base_Type (Entity (Subt))) = Type_Id
10796 (Is_Class_Wide_Type (Entity (Subt))
10798 Chars (Etype (Base_Type (Entity (Subt)))) =
10802 -- A reference to the current type may appear as the prefix of
10803 -- a 'Class attribute.
10805 elsif Nkind (Subt) = N_Attribute_Reference
10806 and then Attribute_Name (Subt) = Name_Class
10808 return Names_T (Prefix (Subt));
10819 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10820 Param_Spec : Node_Id;
10822 Acc_Subprg : constant Node_Id :=
10823 Access_To_Subprogram_Definition (Acc_Def);
10826 if No (Acc_Subprg) then
10827 return Designates_T (Subtype_Mark (Acc_Def));
10830 -- Component is an access_to_subprogram: examine its formals,
10831 -- and result definition in the case of an access_to_function.
10833 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10834 while Present (Param_Spec) loop
10835 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10836 and then Mentions_T (Parameter_Type (Param_Spec))
10840 elsif Designates_T (Parameter_Type (Param_Spec)) then
10847 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10848 if Nkind (Result_Definition (Acc_Subprg)) =
10849 N_Access_Definition
10851 return Mentions_T (Result_Definition (Acc_Subprg));
10853 return Designates_T (Result_Definition (Acc_Subprg));
10860 -- Start of processing for Check_Anonymous_Access_Components
10863 if No (Comp_List) then
10867 Comp := First (Component_Items (Comp_List));
10868 while Present (Comp) loop
10869 if Nkind (Comp) = N_Component_Declaration
10871 (Access_Definition (Component_Definition (Comp)))
10873 Mentions_T (Access_Definition (Component_Definition (Comp)))
10875 Comp_Def := Component_Definition (Comp);
10877 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10879 Build_Incomplete_Type_Declaration;
10880 Anon_Access := Make_Temporary (Loc, 'S');
10882 -- Create a declaration for the anonymous access type: either
10883 -- an access_to_object or an access_to_subprogram.
10885 if Present (Acc_Def) then
10886 if Nkind (Acc_Def) = N_Access_Function_Definition then
10888 Make_Access_Function_Definition (Loc,
10889 Parameter_Specifications =>
10890 Parameter_Specifications (Acc_Def),
10891 Result_Definition => Result_Definition (Acc_Def));
10894 Make_Access_Procedure_Definition (Loc,
10895 Parameter_Specifications =>
10896 Parameter_Specifications (Acc_Def));
10901 Make_Access_To_Object_Definition (Loc,
10902 Subtype_Indication =>
10904 (Subtype_Mark (Access_Definition (Comp_Def))));
10906 Set_Constant_Present
10907 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10909 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10912 Set_Null_Exclusion_Present
10914 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10917 Make_Full_Type_Declaration (Loc,
10918 Defining_Identifier => Anon_Access,
10919 Type_Definition => Type_Def);
10921 Insert_Before (Typ_Decl, Decl);
10924 -- If an access to subprogram, create the extra formals
10926 if Present (Acc_Def) then
10927 Create_Extra_Formals (Designated_Type (Anon_Access));
10929 -- If an access to object, preserve entity of designated type,
10930 -- for ASIS use, before rewriting the component definition.
10937 Desig := Entity (Subtype_Indication (Type_Def));
10939 -- If the access definition is to the current record,
10940 -- the visible entity at this point is an incomplete
10941 -- type. Retrieve the full view to simplify ASIS queries
10943 if Ekind (Desig) = E_Incomplete_Type then
10944 Desig := Full_View (Desig);
10948 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10953 Make_Component_Definition (Loc,
10954 Subtype_Indication =>
10955 New_Occurrence_Of (Anon_Access, Loc)));
10957 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10958 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10960 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10963 Set_Is_Local_Anonymous_Access (Anon_Access);
10969 if Present (Variant_Part (Comp_List)) then
10973 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10974 while Present (V) loop
10975 Check_Anonymous_Access_Components
10976 (Typ_Decl, Typ, Prev, Component_List (V));
10977 Next_Non_Pragma (V);
10981 end Check_Anonymous_Access_Components;
10983 ----------------------
10984 -- Check_Completion --
10985 ----------------------
10987 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10990 procedure Post_Error;
10991 -- Post error message for lack of completion for entity E
10997 procedure Post_Error is
10998 procedure Missing_Body;
10999 -- Output missing body message
11005 procedure Missing_Body is
11007 -- Spec is in same unit, so we can post on spec
11009 if In_Same_Source_Unit (Body_Id, E) then
11010 Error_Msg_N ("missing body for &", E);
11012 -- Spec is in a separate unit, so we have to post on the body
11015 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
11019 -- Start of processing for Post_Error
11022 if not Comes_From_Source (E) then
11023 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
11025 -- It may be an anonymous protected type created for a
11026 -- single variable. Post error on variable, if present.
11032 Var := First_Entity (Current_Scope);
11033 while Present (Var) loop
11034 exit when Etype (Var) = E
11035 and then Comes_From_Source (Var);
11040 if Present (Var) then
11047 -- If a generated entity has no completion, then either previous
11048 -- semantic errors have disabled the expansion phase, or else we had
11049 -- missing subunits, or else we are compiling without expansion,
11050 -- or else something is very wrong.
11052 if not Comes_From_Source (E) then
11054 (Serious_Errors_Detected > 0
11055 or else Configurable_Run_Time_Violations > 0
11056 or else Subunits_Missing
11057 or else not Expander_Active);
11060 -- Here for source entity
11063 -- Here if no body to post the error message, so we post the error
11064 -- on the declaration that has no completion. This is not really
11065 -- the right place to post it, think about this later ???
11067 if No (Body_Id) then
11068 if Is_Type (E) then
11070 ("missing full declaration for }", Parent (E), E);
11072 Error_Msg_NE ("missing body for &", Parent (E), E);
11075 -- Package body has no completion for a declaration that appears
11076 -- in the corresponding spec. Post error on the body, with a
11077 -- reference to the non-completed declaration.
11080 Error_Msg_Sloc := Sloc (E);
11082 if Is_Type (E) then
11083 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
11085 elsif Is_Overloadable (E)
11086 and then Current_Entity_In_Scope (E) /= E
11088 -- It may be that the completion is mistyped and appears as
11089 -- a distinct overloading of the entity.
11092 Candidate : constant Entity_Id :=
11093 Current_Entity_In_Scope (E);
11094 Decl : constant Node_Id :=
11095 Unit_Declaration_Node (Candidate);
11098 if Is_Overloadable (Candidate)
11099 and then Ekind (Candidate) = Ekind (E)
11100 and then Nkind (Decl) = N_Subprogram_Body
11101 and then Acts_As_Spec (Decl)
11103 Check_Type_Conformant (Candidate, E);
11119 Pack_Id : constant Entity_Id := Current_Scope;
11121 -- Start of processing for Check_Completion
11124 E := First_Entity (Pack_Id);
11125 while Present (E) loop
11126 if Is_Intrinsic_Subprogram (E) then
11129 -- The following situation requires special handling: a child unit
11130 -- that appears in the context clause of the body of its parent:
11132 -- procedure Parent.Child (...);
11134 -- with Parent.Child;
11135 -- package body Parent is
11137 -- Here Parent.Child appears as a local entity, but should not be
11138 -- flagged as requiring completion, because it is a compilation
11141 -- Ignore missing completion for a subprogram that does not come from
11142 -- source (including the _Call primitive operation of RAS types,
11143 -- which has to have the flag Comes_From_Source for other purposes):
11144 -- we assume that the expander will provide the missing completion.
11145 -- In case of previous errors, other expansion actions that provide
11146 -- bodies for null procedures with not be invoked, so inhibit message
11149 -- Note that E_Operator is not in the list that follows, because
11150 -- this kind is reserved for predefined operators, that are
11151 -- intrinsic and do not need completion.
11153 elsif Ekind_In (E, E_Function,
11155 E_Generic_Function,
11156 E_Generic_Procedure)
11158 if Has_Completion (E) then
11161 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
11164 elsif Is_Subprogram (E)
11165 and then (not Comes_From_Source (E)
11166 or else Chars (E) = Name_uCall)
11171 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
11175 elsif Nkind (Parent (E)) = N_Procedure_Specification
11176 and then Null_Present (Parent (E))
11177 and then Serious_Errors_Detected > 0
11185 elsif Is_Entry (E) then
11186 if not Has_Completion (E) and then
11187 (Ekind (Scope (E)) = E_Protected_Object
11188 or else Ekind (Scope (E)) = E_Protected_Type)
11193 elsif Is_Package_Or_Generic_Package (E) then
11194 if Unit_Requires_Body (E) then
11195 if not Has_Completion (E)
11196 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
11202 elsif not Is_Child_Unit (E) then
11203 May_Need_Implicit_Body (E);
11206 -- A formal incomplete type (Ada 2012) does not require a completion;
11207 -- other incomplete type declarations do.
11209 elsif Ekind (E) = E_Incomplete_Type
11210 and then No (Underlying_Type (E))
11211 and then not Is_Generic_Type (E)
11215 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
11216 and then not Has_Completion (E)
11220 -- A single task declared in the current scope is a constant, verify
11221 -- that the body of its anonymous type is in the same scope. If the
11222 -- task is defined elsewhere, this may be a renaming declaration for
11223 -- which no completion is needed.
11225 elsif Ekind (E) = E_Constant
11226 and then Ekind (Etype (E)) = E_Task_Type
11227 and then not Has_Completion (Etype (E))
11228 and then Scope (Etype (E)) = Current_Scope
11232 elsif Ekind (E) = E_Protected_Object
11233 and then not Has_Completion (Etype (E))
11237 elsif Ekind (E) = E_Record_Type then
11238 if Is_Tagged_Type (E) then
11239 Check_Abstract_Overriding (E);
11240 Check_Conventions (E);
11243 Check_Aliased_Component_Types (E);
11245 elsif Ekind (E) = E_Array_Type then
11246 Check_Aliased_Component_Types (E);
11252 end Check_Completion;
11254 ------------------------------------
11255 -- Check_CPP_Type_Has_No_Defaults --
11256 ------------------------------------
11258 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11259 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11264 -- Obtain the component list
11266 if Nkind (Tdef) = N_Record_Definition then
11267 Clist := Component_List (Tdef);
11268 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11269 Clist := Component_List (Record_Extension_Part (Tdef));
11272 -- Check all components to ensure no default expressions
11274 if Present (Clist) then
11275 Comp := First (Component_Items (Clist));
11276 while Present (Comp) loop
11277 if Present (Expression (Comp)) then
11279 ("component of imported 'C'P'P type cannot have "
11280 & "default expression", Expression (Comp));
11286 end Check_CPP_Type_Has_No_Defaults;
11288 ----------------------------
11289 -- Check_Delta_Expression --
11290 ----------------------------
11292 procedure Check_Delta_Expression (E : Node_Id) is
11294 if not (Is_Real_Type (Etype (E))) then
11295 Wrong_Type (E, Any_Real);
11297 elsif not Is_OK_Static_Expression (E) then
11298 Flag_Non_Static_Expr
11299 ("non-static expression used for delta value!", E);
11301 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11302 Error_Msg_N ("delta expression must be positive", E);
11308 -- If any of above errors occurred, then replace the incorrect
11309 -- expression by the real 0.1, which should prevent further errors.
11312 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11313 Analyze_And_Resolve (E, Standard_Float);
11314 end Check_Delta_Expression;
11316 -----------------------------
11317 -- Check_Digits_Expression --
11318 -----------------------------
11320 procedure Check_Digits_Expression (E : Node_Id) is
11322 if not (Is_Integer_Type (Etype (E))) then
11323 Wrong_Type (E, Any_Integer);
11325 elsif not Is_OK_Static_Expression (E) then
11326 Flag_Non_Static_Expr
11327 ("non-static expression used for digits value!", E);
11329 elsif Expr_Value (E) <= 0 then
11330 Error_Msg_N ("digits value must be greater than zero", E);
11336 -- If any of above errors occurred, then replace the incorrect
11337 -- expression by the integer 1, which should prevent further errors.
11339 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11340 Analyze_And_Resolve (E, Standard_Integer);
11342 end Check_Digits_Expression;
11344 --------------------------
11345 -- Check_Initialization --
11346 --------------------------
11348 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11350 -- Special processing for limited types
11352 if Is_Limited_Type (T)
11353 and then not In_Instance
11354 and then not In_Inlined_Body
11356 if not OK_For_Limited_Init (T, Exp) then
11358 -- In GNAT mode, this is just a warning, to allow it to be evilly
11359 -- turned off. Otherwise it is a real error.
11363 ("??cannot initialize entities of limited type!", Exp);
11365 elsif Ada_Version < Ada_2005 then
11367 -- The side effect removal machinery may generate illegal Ada
11368 -- code to avoid the usage of access types and 'reference in
11369 -- SPARK mode. Since this is legal code with respect to theorem
11370 -- proving, do not emit the error.
11373 and then Nkind (Exp) = N_Function_Call
11374 and then Nkind (Parent (Exp)) = N_Object_Declaration
11375 and then not Comes_From_Source
11376 (Defining_Identifier (Parent (Exp)))
11382 ("cannot initialize entities of limited type", Exp);
11383 Explain_Limited_Type (T, Exp);
11387 -- Specialize error message according to kind of illegal
11388 -- initial expression.
11390 if Nkind (Exp) = N_Type_Conversion
11391 and then Nkind (Expression (Exp)) = N_Function_Call
11394 ("illegal context for call"
11395 & " to function with limited result", Exp);
11399 ("initialization of limited object requires aggregate "
11400 & "or function call", Exp);
11406 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11407 -- set unless we can be sure that no range check is required.
11409 if (GNATprove_Mode or not Expander_Active)
11410 and then Is_Scalar_Type (T)
11411 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11413 Set_Do_Range_Check (Exp);
11415 end Check_Initialization;
11417 ----------------------
11418 -- Check_Interfaces --
11419 ----------------------
11421 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11422 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11425 Iface_Def : Node_Id;
11426 Iface_Typ : Entity_Id;
11427 Parent_Node : Node_Id;
11429 Is_Task : Boolean := False;
11430 -- Set True if parent type or any progenitor is a task interface
11432 Is_Protected : Boolean := False;
11433 -- Set True if parent type or any progenitor is a protected interface
11435 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11436 -- Check that a progenitor is compatible with declaration. If an error
11437 -- message is output, it is posted on Error_Node.
11443 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11444 Iface_Id : constant Entity_Id :=
11445 Defining_Identifier (Parent (Iface_Def));
11446 Type_Def : Node_Id;
11449 if Nkind (N) = N_Private_Extension_Declaration then
11452 Type_Def := Type_Definition (N);
11455 if Is_Task_Interface (Iface_Id) then
11458 elsif Is_Protected_Interface (Iface_Id) then
11459 Is_Protected := True;
11462 if Is_Synchronized_Interface (Iface_Id) then
11464 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11465 -- extension derived from a synchronized interface must explicitly
11466 -- be declared synchronized, because the full view will be a
11467 -- synchronized type.
11469 if Nkind (N) = N_Private_Extension_Declaration then
11470 if not Synchronized_Present (N) then
11472 ("private extension of& must be explicitly synchronized",
11476 -- However, by 3.9.4(16/2), a full type that is a record extension
11477 -- is never allowed to derive from a synchronized interface (note
11478 -- that interfaces must be excluded from this check, because those
11479 -- are represented by derived type definitions in some cases).
11481 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11482 and then not Interface_Present (Type_Definition (N))
11484 Error_Msg_N ("record extension cannot derive from synchronized "
11485 & "interface", Error_Node);
11489 -- Check that the characteristics of the progenitor are compatible
11490 -- with the explicit qualifier in the declaration.
11491 -- The check only applies to qualifiers that come from source.
11492 -- Limited_Present also appears in the declaration of corresponding
11493 -- records, and the check does not apply to them.
11495 if Limited_Present (Type_Def)
11497 Is_Concurrent_Record_Type (Defining_Identifier (N))
11499 if Is_Limited_Interface (Parent_Type)
11500 and then not Is_Limited_Interface (Iface_Id)
11503 ("progenitor & must be limited interface",
11504 Error_Node, Iface_Id);
11507 (Task_Present (Iface_Def)
11508 or else Protected_Present (Iface_Def)
11509 or else Synchronized_Present (Iface_Def))
11510 and then Nkind (N) /= N_Private_Extension_Declaration
11511 and then not Error_Posted (N)
11514 ("progenitor & must be limited interface",
11515 Error_Node, Iface_Id);
11518 -- Protected interfaces can only inherit from limited, synchronized
11519 -- or protected interfaces.
11521 elsif Nkind (N) = N_Full_Type_Declaration
11522 and then Protected_Present (Type_Def)
11524 if Limited_Present (Iface_Def)
11525 or else Synchronized_Present (Iface_Def)
11526 or else Protected_Present (Iface_Def)
11530 elsif Task_Present (Iface_Def) then
11531 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11532 & "from task interface", Error_Node);
11535 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11536 & "from non-limited interface", Error_Node);
11539 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11540 -- limited and synchronized.
11542 elsif Synchronized_Present (Type_Def) then
11543 if Limited_Present (Iface_Def)
11544 or else Synchronized_Present (Iface_Def)
11548 elsif Protected_Present (Iface_Def)
11549 and then Nkind (N) /= N_Private_Extension_Declaration
11551 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11552 & "from protected interface", Error_Node);
11554 elsif Task_Present (Iface_Def)
11555 and then Nkind (N) /= N_Private_Extension_Declaration
11557 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11558 & "from task interface", Error_Node);
11560 elsif not Is_Limited_Interface (Iface_Id) then
11561 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11562 & "from non-limited interface", Error_Node);
11565 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11566 -- synchronized or task interfaces.
11568 elsif Nkind (N) = N_Full_Type_Declaration
11569 and then Task_Present (Type_Def)
11571 if Limited_Present (Iface_Def)
11572 or else Synchronized_Present (Iface_Def)
11573 or else Task_Present (Iface_Def)
11577 elsif Protected_Present (Iface_Def) then
11578 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11579 & "protected interface", Error_Node);
11582 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11583 & "non-limited interface", Error_Node);
11588 -- Start of processing for Check_Interfaces
11591 if Is_Interface (Parent_Type) then
11592 if Is_Task_Interface (Parent_Type) then
11595 elsif Is_Protected_Interface (Parent_Type) then
11596 Is_Protected := True;
11600 if Nkind (N) = N_Private_Extension_Declaration then
11602 -- Check that progenitors are compatible with declaration
11604 Iface := First (Interface_List (Def));
11605 while Present (Iface) loop
11606 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11608 Parent_Node := Parent (Base_Type (Iface_Typ));
11609 Iface_Def := Type_Definition (Parent_Node);
11611 if not Is_Interface (Iface_Typ) then
11612 Diagnose_Interface (Iface, Iface_Typ);
11614 Check_Ifaces (Iface_Def, Iface);
11620 if Is_Task and Is_Protected then
11622 ("type cannot derive from task and protected interface", N);
11628 -- Full type declaration of derived type.
11629 -- Check compatibility with parent if it is interface type
11631 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11632 and then Is_Interface (Parent_Type)
11634 Parent_Node := Parent (Parent_Type);
11636 -- More detailed checks for interface varieties
11639 (Iface_Def => Type_Definition (Parent_Node),
11640 Error_Node => Subtype_Indication (Type_Definition (N)));
11643 Iface := First (Interface_List (Def));
11644 while Present (Iface) loop
11645 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11647 Parent_Node := Parent (Base_Type (Iface_Typ));
11648 Iface_Def := Type_Definition (Parent_Node);
11650 if not Is_Interface (Iface_Typ) then
11651 Diagnose_Interface (Iface, Iface_Typ);
11654 -- "The declaration of a specific descendant of an interface
11655 -- type freezes the interface type" RM 13.14
11657 Freeze_Before (N, Iface_Typ);
11658 Check_Ifaces (Iface_Def, Error_Node => Iface);
11664 if Is_Task and Is_Protected then
11666 ("type cannot derive from task and protected interface", N);
11668 end Check_Interfaces;
11670 ------------------------------------
11671 -- Check_Or_Process_Discriminants --
11672 ------------------------------------
11674 -- If an incomplete or private type declaration was already given for the
11675 -- type, the discriminants may have already been processed if they were
11676 -- present on the incomplete declaration. In this case a full conformance
11677 -- check has been performed in Find_Type_Name, and we then recheck here
11678 -- some properties that can't be checked on the partial view alone.
11679 -- Otherwise we call Process_Discriminants.
11681 procedure Check_Or_Process_Discriminants
11684 Prev : Entity_Id := Empty)
11687 if Has_Discriminants (T) then
11689 -- Discriminants are already set on T if they were already present
11690 -- on the partial view. Make them visible to component declarations.
11694 -- Discriminant on T (full view) referencing expr on partial view
11696 Prev_D : Entity_Id;
11697 -- Entity of corresponding discriminant on partial view
11700 -- Discriminant specification for full view, expression is
11701 -- the syntactic copy on full view (which has been checked for
11702 -- conformance with partial view), only used here to post error
11706 D := First_Discriminant (T);
11707 New_D := First (Discriminant_Specifications (N));
11708 while Present (D) loop
11709 Prev_D := Current_Entity (D);
11710 Set_Current_Entity (D);
11711 Set_Is_Immediately_Visible (D);
11712 Set_Homonym (D, Prev_D);
11714 -- Handle the case where there is an untagged partial view and
11715 -- the full view is tagged: must disallow discriminants with
11716 -- defaults, unless compiling for Ada 2012, which allows a
11717 -- limited tagged type to have defaulted discriminants (see
11718 -- AI05-0214). However, suppress error here if it was already
11719 -- reported on the default expression of the partial view.
11721 if Is_Tagged_Type (T)
11722 and then Present (Expression (Parent (D)))
11723 and then (not Is_Limited_Type (Current_Scope)
11724 or else Ada_Version < Ada_2012)
11725 and then not Error_Posted (Expression (Parent (D)))
11727 if Ada_Version >= Ada_2012 then
11729 ("discriminants of nonlimited tagged type cannot have "
11731 Expression (New_D));
11734 ("discriminants of tagged type cannot have defaults",
11735 Expression (New_D));
11739 -- Ada 2005 (AI-230): Access discriminant allowed in
11740 -- non-limited record types.
11742 if Ada_Version < Ada_2005 then
11744 -- This restriction gets applied to the full type here. It
11745 -- has already been applied earlier to the partial view.
11747 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11750 Next_Discriminant (D);
11755 elsif Present (Discriminant_Specifications (N)) then
11756 Process_Discriminants (N, Prev);
11758 end Check_Or_Process_Discriminants;
11760 ----------------------
11761 -- Check_Real_Bound --
11762 ----------------------
11764 procedure Check_Real_Bound (Bound : Node_Id) is
11766 if not Is_Real_Type (Etype (Bound)) then
11768 ("bound in real type definition must be of real type", Bound);
11770 elsif not Is_OK_Static_Expression (Bound) then
11771 Flag_Non_Static_Expr
11772 ("non-static expression used for real type bound!", Bound);
11779 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11781 Resolve (Bound, Standard_Float);
11782 end Check_Real_Bound;
11784 ------------------------------
11785 -- Complete_Private_Subtype --
11786 ------------------------------
11788 procedure Complete_Private_Subtype
11791 Full_Base : Entity_Id;
11792 Related_Nod : Node_Id)
11794 Save_Next_Entity : Entity_Id;
11795 Save_Homonym : Entity_Id;
11798 -- Set semantic attributes for (implicit) private subtype completion.
11799 -- If the full type has no discriminants, then it is a copy of the
11800 -- full view of the base. Otherwise, it is a subtype of the base with
11801 -- a possible discriminant constraint. Save and restore the original
11802 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11803 -- not corrupt the entity chain.
11805 -- Note that the type of the full view is the same entity as the type
11806 -- of the partial view. In this fashion, the subtype has access to the
11807 -- correct view of the parent.
11809 Save_Next_Entity := Next_Entity (Full);
11810 Save_Homonym := Homonym (Priv);
11812 case Ekind (Full_Base) is
11813 when Class_Wide_Kind
11820 Copy_Node (Priv, Full);
11822 Set_Has_Discriminants
11823 (Full, Has_Discriminants (Full_Base));
11824 Set_Has_Unknown_Discriminants
11825 (Full, Has_Unknown_Discriminants (Full_Base));
11826 Set_First_Entity (Full, First_Entity (Full_Base));
11827 Set_Last_Entity (Full, Last_Entity (Full_Base));
11829 -- If the underlying base type is constrained, we know that the
11830 -- full view of the subtype is constrained as well (the converse
11831 -- is not necessarily true).
11833 if Is_Constrained (Full_Base) then
11834 Set_Is_Constrained (Full);
11838 Copy_Node (Full_Base, Full);
11840 Set_Chars (Full, Chars (Priv));
11841 Conditional_Delay (Full, Priv);
11842 Set_Sloc (Full, Sloc (Priv));
11845 Set_Next_Entity (Full, Save_Next_Entity);
11846 Set_Homonym (Full, Save_Homonym);
11847 Set_Associated_Node_For_Itype (Full, Related_Nod);
11849 -- Set common attributes for all subtypes: kind, convention, etc.
11851 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11852 Set_Convention (Full, Convention (Full_Base));
11854 -- The Etype of the full view is inconsistent. Gigi needs to see the
11855 -- structural full view, which is what the current scheme gives: the
11856 -- Etype of the full view is the etype of the full base. However, if the
11857 -- full base is a derived type, the full view then looks like a subtype
11858 -- of the parent, not a subtype of the full base. If instead we write:
11860 -- Set_Etype (Full, Full_Base);
11862 -- then we get inconsistencies in the front-end (confusion between
11863 -- views). Several outstanding bugs are related to this ???
11865 Set_Is_First_Subtype (Full, False);
11866 Set_Scope (Full, Scope (Priv));
11867 Set_Size_Info (Full, Full_Base);
11868 Set_RM_Size (Full, RM_Size (Full_Base));
11869 Set_Is_Itype (Full);
11871 -- A subtype of a private-type-without-discriminants, whose full-view
11872 -- has discriminants with default expressions, is not constrained.
11874 if not Has_Discriminants (Priv) then
11875 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11877 if Has_Discriminants (Full_Base) then
11878 Set_Discriminant_Constraint
11879 (Full, Discriminant_Constraint (Full_Base));
11881 -- The partial view may have been indefinite, the full view
11884 Set_Has_Unknown_Discriminants
11885 (Full, Has_Unknown_Discriminants (Full_Base));
11889 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11890 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11892 -- Freeze the private subtype entity if its parent is delayed, and not
11893 -- already frozen. We skip this processing if the type is an anonymous
11894 -- subtype of a record component, or is the corresponding record of a
11895 -- protected type, since these are processed when the enclosing type
11898 if not Is_Type (Scope (Full)) then
11899 Set_Has_Delayed_Freeze (Full,
11900 Has_Delayed_Freeze (Full_Base)
11901 and then (not Is_Frozen (Full_Base)));
11904 Set_Freeze_Node (Full, Empty);
11905 Set_Is_Frozen (Full, False);
11906 Set_Full_View (Priv, Full);
11908 if Has_Discriminants (Full) then
11909 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11910 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11912 if Has_Unknown_Discriminants (Full) then
11913 Set_Discriminant_Constraint (Full, No_Elist);
11917 if Ekind (Full_Base) = E_Record_Type
11918 and then Has_Discriminants (Full_Base)
11919 and then Has_Discriminants (Priv) -- might not, if errors
11920 and then not Has_Unknown_Discriminants (Priv)
11921 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11923 Create_Constrained_Components
11924 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11926 -- If the full base is itself derived from private, build a congruent
11927 -- subtype of its underlying type, for use by the back end. For a
11928 -- constrained record component, the declaration cannot be placed on
11929 -- the component list, but it must nevertheless be built an analyzed, to
11930 -- supply enough information for Gigi to compute the size of component.
11932 elsif Ekind (Full_Base) in Private_Kind
11933 and then Is_Derived_Type (Full_Base)
11934 and then Has_Discriminants (Full_Base)
11935 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11937 if not Is_Itype (Priv)
11939 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11941 Build_Underlying_Full_View
11942 (Parent (Priv), Full, Etype (Full_Base));
11944 elsif Nkind (Related_Nod) = N_Component_Declaration then
11945 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11948 elsif Is_Record_Type (Full_Base) then
11950 -- Show Full is simply a renaming of Full_Base
11952 Set_Cloned_Subtype (Full, Full_Base);
11955 -- It is unsafe to share the bounds of a scalar type, because the Itype
11956 -- is elaborated on demand, and if a bound is non-static then different
11957 -- orders of elaboration in different units will lead to different
11958 -- external symbols.
11960 if Is_Scalar_Type (Full_Base) then
11961 Set_Scalar_Range (Full,
11962 Make_Range (Sloc (Related_Nod),
11964 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11966 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11968 -- This completion inherits the bounds of the full parent, but if
11969 -- the parent is an unconstrained floating point type, so is the
11972 if Is_Floating_Point_Type (Full_Base) then
11973 Set_Includes_Infinities
11974 (Scalar_Range (Full), Has_Infinities (Full_Base));
11978 -- ??? It seems that a lot of fields are missing that should be copied
11979 -- from Full_Base to Full. Here are some that are introduced in a
11980 -- non-disruptive way but a cleanup is necessary.
11982 if Is_Tagged_Type (Full_Base) then
11983 Set_Is_Tagged_Type (Full);
11984 Set_Direct_Primitive_Operations
11985 (Full, Direct_Primitive_Operations (Full_Base));
11986 Set_No_Tagged_Streams_Pragma
11987 (Full, No_Tagged_Streams_Pragma (Full_Base));
11989 -- Inherit class_wide type of full_base in case the partial view was
11990 -- not tagged. Otherwise it has already been created when the private
11991 -- subtype was analyzed.
11993 if No (Class_Wide_Type (Full)) then
11994 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11997 -- If this is a subtype of a protected or task type, constrain its
11998 -- corresponding record, unless this is a subtype without constraints,
11999 -- i.e. a simple renaming as with an actual subtype in an instance.
12001 elsif Is_Concurrent_Type (Full_Base) then
12002 if Has_Discriminants (Full)
12003 and then Present (Corresponding_Record_Type (Full_Base))
12005 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
12007 Set_Corresponding_Record_Type (Full,
12008 Constrain_Corresponding_Record
12009 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
12012 Set_Corresponding_Record_Type (Full,
12013 Corresponding_Record_Type (Full_Base));
12017 -- Link rep item chain, and also setting of Has_Predicates from private
12018 -- subtype to full subtype, since we will need these on the full subtype
12019 -- to create the predicate function. Note that the full subtype may
12020 -- already have rep items, inherited from the full view of the base
12021 -- type, so we must be sure not to overwrite these entries.
12026 Next_Item : Node_Id;
12027 Priv_Item : Node_Id;
12030 Item := First_Rep_Item (Full);
12031 Priv_Item := First_Rep_Item (Priv);
12033 -- If no existing rep items on full type, we can just link directly
12034 -- to the list of items on the private type, if any exist.. Same if
12035 -- the rep items are only those inherited from the base
12038 or else Nkind (Item) /= N_Aspect_Specification
12039 or else Entity (Item) = Full_Base)
12040 and then Present (First_Rep_Item (Priv))
12042 Set_First_Rep_Item (Full, Priv_Item);
12044 -- Otherwise, search to the end of items currently linked to the full
12045 -- subtype and append the private items to the end. However, if Priv
12046 -- and Full already have the same list of rep items, then the append
12047 -- is not done, as that would create a circularity.
12049 -- The partial view may have a predicate and the rep item lists of
12050 -- both views agree when inherited from the same ancestor. In that
12051 -- case, simply propagate the list from one view to the other.
12052 -- A more complex analysis needed here ???
12054 elsif Present (Priv_Item)
12055 and then Item = Next_Rep_Item (Priv_Item)
12057 Set_First_Rep_Item (Full, Priv_Item);
12059 elsif Item /= Priv_Item then
12062 Next_Item := Next_Rep_Item (Item);
12063 exit when No (Next_Item);
12066 -- If the private view has aspect specifications, the full view
12067 -- inherits them. Since these aspects may already have been
12068 -- attached to the full view during derivation, do not append
12069 -- them if already present.
12071 if Item = First_Rep_Item (Priv) then
12077 -- And link the private type items at the end of the chain
12080 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
12085 -- Make sure Has_Predicates is set on full type if it is set on the
12086 -- private type. Note that it may already be set on the full type and
12087 -- if so, we don't want to unset it. Similarly, propagate information
12088 -- about delayed aspects, because the corresponding pragmas must be
12089 -- analyzed when one of the views is frozen. This last step is needed
12090 -- in particular when the full type is a scalar type for which an
12091 -- anonymous base type is constructed.
12093 -- The predicate functions are generated either at the freeze point
12094 -- of the type or at the end of the visible part, and we must avoid
12095 -- generating them twice.
12097 if Has_Predicates (Priv) then
12098 Set_Has_Predicates (Full);
12100 if Present (Predicate_Function (Priv))
12101 and then No (Predicate_Function (Full))
12103 Set_Predicate_Function (Full, Predicate_Function (Priv));
12107 if Has_Delayed_Aspects (Priv) then
12108 Set_Has_Delayed_Aspects (Full);
12110 end Complete_Private_Subtype;
12112 ----------------------------
12113 -- Constant_Redeclaration --
12114 ----------------------------
12116 procedure Constant_Redeclaration
12121 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
12122 Obj_Def : constant Node_Id := Object_Definition (N);
12125 procedure Check_Possible_Deferred_Completion
12126 (Prev_Id : Entity_Id;
12127 Prev_Obj_Def : Node_Id;
12128 Curr_Obj_Def : Node_Id);
12129 -- Determine whether the two object definitions describe the partial
12130 -- and the full view of a constrained deferred constant. Generate
12131 -- a subtype for the full view and verify that it statically matches
12132 -- the subtype of the partial view.
12134 procedure Check_Recursive_Declaration (Typ : Entity_Id);
12135 -- If deferred constant is an access type initialized with an allocator,
12136 -- check whether there is an illegal recursion in the definition,
12137 -- through a default value of some record subcomponent. This is normally
12138 -- detected when generating init procs, but requires this additional
12139 -- mechanism when expansion is disabled.
12141 ----------------------------------------
12142 -- Check_Possible_Deferred_Completion --
12143 ----------------------------------------
12145 procedure Check_Possible_Deferred_Completion
12146 (Prev_Id : Entity_Id;
12147 Prev_Obj_Def : Node_Id;
12148 Curr_Obj_Def : Node_Id)
12151 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
12152 and then Present (Constraint (Prev_Obj_Def))
12153 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
12154 and then Present (Constraint (Curr_Obj_Def))
12157 Loc : constant Source_Ptr := Sloc (N);
12158 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
12159 Decl : constant Node_Id :=
12160 Make_Subtype_Declaration (Loc,
12161 Defining_Identifier => Def_Id,
12162 Subtype_Indication =>
12163 Relocate_Node (Curr_Obj_Def));
12166 Insert_Before_And_Analyze (N, Decl);
12167 Set_Etype (Id, Def_Id);
12169 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
12170 Error_Msg_Sloc := Sloc (Prev_Id);
12171 Error_Msg_N ("subtype does not statically match deferred "
12172 & "declaration #", N);
12176 end Check_Possible_Deferred_Completion;
12178 ---------------------------------
12179 -- Check_Recursive_Declaration --
12180 ---------------------------------
12182 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
12186 if Is_Record_Type (Typ) then
12187 Comp := First_Component (Typ);
12188 while Present (Comp) loop
12189 if Comes_From_Source (Comp) then
12190 if Present (Expression (Parent (Comp)))
12191 and then Is_Entity_Name (Expression (Parent (Comp)))
12192 and then Entity (Expression (Parent (Comp))) = Prev
12194 Error_Msg_Sloc := Sloc (Parent (Comp));
12196 ("illegal circularity with declaration for & #",
12200 elsif Is_Record_Type (Etype (Comp)) then
12201 Check_Recursive_Declaration (Etype (Comp));
12205 Next_Component (Comp);
12208 end Check_Recursive_Declaration;
12210 -- Start of processing for Constant_Redeclaration
12213 if Nkind (Parent (Prev)) = N_Object_Declaration then
12214 if Nkind (Object_Definition
12215 (Parent (Prev))) = N_Subtype_Indication
12217 -- Find type of new declaration. The constraints of the two
12218 -- views must match statically, but there is no point in
12219 -- creating an itype for the full view.
12221 if Nkind (Obj_Def) = N_Subtype_Indication then
12222 Find_Type (Subtype_Mark (Obj_Def));
12223 New_T := Entity (Subtype_Mark (Obj_Def));
12226 Find_Type (Obj_Def);
12227 New_T := Entity (Obj_Def);
12233 -- The full view may impose a constraint, even if the partial
12234 -- view does not, so construct the subtype.
12236 New_T := Find_Type_Of_Object (Obj_Def, N);
12241 -- Current declaration is illegal, diagnosed below in Enter_Name
12247 -- If previous full declaration or a renaming declaration exists, or if
12248 -- a homograph is present, let Enter_Name handle it, either with an
12249 -- error or with the removal of an overridden implicit subprogram.
12250 -- The previous one is a full declaration if it has an expression
12251 -- (which in the case of an aggregate is indicated by the Init flag).
12253 if Ekind (Prev) /= E_Constant
12254 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12255 or else Present (Expression (Parent (Prev)))
12256 or else Has_Init_Expression (Parent (Prev))
12257 or else Present (Full_View (Prev))
12261 -- Verify that types of both declarations match, or else that both types
12262 -- are anonymous access types whose designated subtypes statically match
12263 -- (as allowed in Ada 2005 by AI-385).
12265 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12267 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12268 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12269 or else Is_Access_Constant (Etype (New_T)) /=
12270 Is_Access_Constant (Etype (Prev))
12271 or else Can_Never_Be_Null (Etype (New_T)) /=
12272 Can_Never_Be_Null (Etype (Prev))
12273 or else Null_Exclusion_Present (Parent (Prev)) /=
12274 Null_Exclusion_Present (Parent (Id))
12275 or else not Subtypes_Statically_Match
12276 (Designated_Type (Etype (Prev)),
12277 Designated_Type (Etype (New_T))))
12279 Error_Msg_Sloc := Sloc (Prev);
12280 Error_Msg_N ("type does not match declaration#", N);
12281 Set_Full_View (Prev, Id);
12282 Set_Etype (Id, Any_Type);
12284 -- A deferred constant whose type is an anonymous array is always
12285 -- illegal (unless imported). A detailed error message might be
12286 -- helpful for Ada beginners.
12288 if Nkind (Object_Definition (Parent (Prev)))
12289 = N_Constrained_Array_Definition
12290 and then Nkind (Object_Definition (N))
12291 = N_Constrained_Array_Definition
12293 Error_Msg_N ("\each anonymous array is a distinct type", N);
12294 Error_Msg_N ("a deferred constant must have a named type",
12295 Object_Definition (Parent (Prev)));
12299 Null_Exclusion_Present (Parent (Prev))
12300 and then not Null_Exclusion_Present (N)
12302 Error_Msg_Sloc := Sloc (Prev);
12303 Error_Msg_N ("null-exclusion does not match declaration#", N);
12304 Set_Full_View (Prev, Id);
12305 Set_Etype (Id, Any_Type);
12307 -- If so, process the full constant declaration
12310 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12311 -- the deferred declaration is constrained, then the subtype defined
12312 -- by the subtype_indication in the full declaration shall match it
12315 Check_Possible_Deferred_Completion
12317 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12318 Curr_Obj_Def => Obj_Def);
12320 Set_Full_View (Prev, Id);
12321 Set_Is_Public (Id, Is_Public (Prev));
12322 Set_Is_Internal (Id);
12323 Append_Entity (Id, Current_Scope);
12325 -- Check ALIASED present if present before (RM 7.4(7))
12327 if Is_Aliased (Prev)
12328 and then not Aliased_Present (N)
12330 Error_Msg_Sloc := Sloc (Prev);
12331 Error_Msg_N ("ALIASED required (see declaration #)", N);
12334 -- Check that placement is in private part and that the incomplete
12335 -- declaration appeared in the visible part.
12337 if Ekind (Current_Scope) = E_Package
12338 and then not In_Private_Part (Current_Scope)
12340 Error_Msg_Sloc := Sloc (Prev);
12342 ("full constant for declaration # must be in private part", N);
12344 elsif Ekind (Current_Scope) = E_Package
12346 List_Containing (Parent (Prev)) /=
12347 Visible_Declarations (Package_Specification (Current_Scope))
12350 ("deferred constant must be declared in visible part",
12354 if Is_Access_Type (T)
12355 and then Nkind (Expression (N)) = N_Allocator
12357 Check_Recursive_Declaration (Designated_Type (T));
12360 -- A deferred constant is a visible entity. If type has invariants,
12361 -- verify that the initial value satisfies them.
12363 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12365 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12368 end Constant_Redeclaration;
12370 ----------------------
12371 -- Constrain_Access --
12372 ----------------------
12374 procedure Constrain_Access
12375 (Def_Id : in out Entity_Id;
12377 Related_Nod : Node_Id)
12379 T : constant Entity_Id := Entity (Subtype_Mark (S));
12380 Desig_Type : constant Entity_Id := Designated_Type (T);
12381 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12382 Constraint_OK : Boolean := True;
12385 if Is_Array_Type (Desig_Type) then
12386 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12388 elsif (Is_Record_Type (Desig_Type)
12389 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12390 and then not Is_Constrained (Desig_Type)
12392 -- ??? The following code is a temporary bypass to ignore a
12393 -- discriminant constraint on access type if it is constraining
12394 -- the current record. Avoid creating the implicit subtype of the
12395 -- record we are currently compiling since right now, we cannot
12396 -- handle these. For now, just return the access type itself.
12398 if Desig_Type = Current_Scope
12399 and then No (Def_Id)
12401 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12402 Def_Id := Entity (Subtype_Mark (S));
12404 -- This call added to ensure that the constraint is analyzed
12405 -- (needed for a B test). Note that we still return early from
12406 -- this procedure to avoid recursive processing. ???
12408 Constrain_Discriminated_Type
12409 (Desig_Subtype, S, Related_Nod, For_Access => True);
12413 -- Enforce rule that the constraint is illegal if there is an
12414 -- unconstrained view of the designated type. This means that the
12415 -- partial view (either a private type declaration or a derivation
12416 -- from a private type) has no discriminants. (Defect Report
12417 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12419 -- Rule updated for Ada 2005: The private type is said to have
12420 -- a constrained partial view, given that objects of the type
12421 -- can be declared. Furthermore, the rule applies to all access
12422 -- types, unlike the rule concerning default discriminants (see
12425 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12426 and then Has_Private_Declaration (Desig_Type)
12427 and then In_Open_Scopes (Scope (Desig_Type))
12428 and then Has_Discriminants (Desig_Type)
12431 Pack : constant Node_Id :=
12432 Unit_Declaration_Node (Scope (Desig_Type));
12437 if Nkind (Pack) = N_Package_Declaration then
12438 Decls := Visible_Declarations (Specification (Pack));
12439 Decl := First (Decls);
12440 while Present (Decl) loop
12441 if (Nkind (Decl) = N_Private_Type_Declaration
12442 and then Chars (Defining_Identifier (Decl)) =
12443 Chars (Desig_Type))
12446 (Nkind (Decl) = N_Full_Type_Declaration
12448 Chars (Defining_Identifier (Decl)) =
12450 and then Is_Derived_Type (Desig_Type)
12452 Has_Private_Declaration (Etype (Desig_Type)))
12454 if No (Discriminant_Specifications (Decl)) then
12456 ("cannot constrain access type if designated "
12457 & "type has constrained partial view", S);
12469 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12470 For_Access => True);
12472 elsif Is_Concurrent_Type (Desig_Type)
12473 and then not Is_Constrained (Desig_Type)
12475 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12478 Error_Msg_N ("invalid constraint on access type", S);
12480 -- We simply ignore an invalid constraint
12482 Desig_Subtype := Desig_Type;
12483 Constraint_OK := False;
12486 if No (Def_Id) then
12487 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12489 Set_Ekind (Def_Id, E_Access_Subtype);
12492 if Constraint_OK then
12493 Set_Etype (Def_Id, Base_Type (T));
12495 if Is_Private_Type (Desig_Type) then
12496 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12499 Set_Etype (Def_Id, Any_Type);
12502 Set_Size_Info (Def_Id, T);
12503 Set_Is_Constrained (Def_Id, Constraint_OK);
12504 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12505 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12506 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12508 Conditional_Delay (Def_Id, T);
12510 -- AI-363 : Subtypes of general access types whose designated types have
12511 -- default discriminants are disallowed. In instances, the rule has to
12512 -- be checked against the actual, of which T is the subtype. In a
12513 -- generic body, the rule is checked assuming that the actual type has
12514 -- defaulted discriminants.
12516 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12517 if Ekind (Base_Type (T)) = E_General_Access_Type
12518 and then Has_Defaulted_Discriminants (Desig_Type)
12520 if Ada_Version < Ada_2005 then
12522 ("access subtype of general access type would not " &
12523 "be allowed in Ada 2005?y?", S);
12526 ("access subtype of general access type not allowed", S);
12529 Error_Msg_N ("\discriminants have defaults", S);
12531 elsif Is_Access_Type (T)
12532 and then Is_Generic_Type (Desig_Type)
12533 and then Has_Discriminants (Desig_Type)
12534 and then In_Package_Body (Current_Scope)
12536 if Ada_Version < Ada_2005 then
12538 ("access subtype would not be allowed in generic body "
12539 & "in Ada 2005?y?", S);
12542 ("access subtype not allowed in generic body", S);
12546 ("\designated type is a discriminated formal", S);
12549 end Constrain_Access;
12551 ---------------------
12552 -- Constrain_Array --
12553 ---------------------
12555 procedure Constrain_Array
12556 (Def_Id : in out Entity_Id;
12558 Related_Nod : Node_Id;
12559 Related_Id : Entity_Id;
12560 Suffix : Character)
12562 C : constant Node_Id := Constraint (SI);
12563 Number_Of_Constraints : Nat := 0;
12566 Constraint_OK : Boolean := True;
12569 T := Entity (Subtype_Mark (SI));
12571 if Is_Access_Type (T) then
12572 T := Designated_Type (T);
12575 -- If an index constraint follows a subtype mark in a subtype indication
12576 -- then the type or subtype denoted by the subtype mark must not already
12577 -- impose an index constraint. The subtype mark must denote either an
12578 -- unconstrained array type or an access type whose designated type
12579 -- is such an array type... (RM 3.6.1)
12581 if Is_Constrained (T) then
12582 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12583 Constraint_OK := False;
12586 S := First (Constraints (C));
12587 while Present (S) loop
12588 Number_Of_Constraints := Number_Of_Constraints + 1;
12592 -- In either case, the index constraint must provide a discrete
12593 -- range for each index of the array type and the type of each
12594 -- discrete range must be the same as that of the corresponding
12595 -- index. (RM 3.6.1)
12597 if Number_Of_Constraints /= Number_Dimensions (T) then
12598 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12599 Constraint_OK := False;
12602 S := First (Constraints (C));
12603 Index := First_Index (T);
12606 -- Apply constraints to each index type
12608 for J in 1 .. Number_Of_Constraints loop
12609 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12617 if No (Def_Id) then
12619 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12620 Set_Parent (Def_Id, Related_Nod);
12623 Set_Ekind (Def_Id, E_Array_Subtype);
12626 Set_Size_Info (Def_Id, (T));
12627 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12628 Set_Etype (Def_Id, Base_Type (T));
12630 if Constraint_OK then
12631 Set_First_Index (Def_Id, First (Constraints (C)));
12633 Set_First_Index (Def_Id, First_Index (T));
12636 Set_Is_Constrained (Def_Id, True);
12637 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12638 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12640 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12641 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12643 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12644 -- We need to initialize the attribute because if Def_Id is previously
12645 -- analyzed through a limited_with clause, it will have the attributes
12646 -- of an incomplete type, one of which is an Elist that overlaps the
12647 -- Packed_Array_Impl_Type field.
12649 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12651 -- Build a freeze node if parent still needs one. Also make sure that
12652 -- the Depends_On_Private status is set because the subtype will need
12653 -- reprocessing at the time the base type does, and also we must set a
12654 -- conditional delay.
12656 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12657 Conditional_Delay (Def_Id, T);
12658 end Constrain_Array;
12660 ------------------------------
12661 -- Constrain_Component_Type --
12662 ------------------------------
12664 function Constrain_Component_Type
12666 Constrained_Typ : Entity_Id;
12667 Related_Node : Node_Id;
12669 Constraints : Elist_Id) return Entity_Id
12671 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12672 Compon_Type : constant Entity_Id := Etype (Comp);
12674 function Build_Constrained_Array_Type
12675 (Old_Type : Entity_Id) return Entity_Id;
12676 -- If Old_Type is an array type, one of whose indexes is constrained
12677 -- by a discriminant, build an Itype whose constraint replaces the
12678 -- discriminant with its value in the constraint.
12680 function Build_Constrained_Discriminated_Type
12681 (Old_Type : Entity_Id) return Entity_Id;
12682 -- Ditto for record components
12684 function Build_Constrained_Access_Type
12685 (Old_Type : Entity_Id) return Entity_Id;
12686 -- Ditto for access types. Makes use of previous two functions, to
12687 -- constrain designated type.
12689 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12690 -- T is an array or discriminated type, C is a list of constraints
12691 -- that apply to T. This routine builds the constrained subtype.
12693 function Is_Discriminant (Expr : Node_Id) return Boolean;
12694 -- Returns True if Expr is a discriminant
12696 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12697 -- Find the value of discriminant Discrim in Constraint
12699 -----------------------------------
12700 -- Build_Constrained_Access_Type --
12701 -----------------------------------
12703 function Build_Constrained_Access_Type
12704 (Old_Type : Entity_Id) return Entity_Id
12706 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12708 Desig_Subtype : Entity_Id;
12712 -- if the original access type was not embedded in the enclosing
12713 -- type definition, there is no need to produce a new access
12714 -- subtype. In fact every access type with an explicit constraint
12715 -- generates an itype whose scope is the enclosing record.
12717 if not Is_Type (Scope (Old_Type)) then
12720 elsif Is_Array_Type (Desig_Type) then
12721 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12723 elsif Has_Discriminants (Desig_Type) then
12725 -- This may be an access type to an enclosing record type for
12726 -- which we are constructing the constrained components. Return
12727 -- the enclosing record subtype. This is not always correct,
12728 -- but avoids infinite recursion. ???
12730 Desig_Subtype := Any_Type;
12732 for J in reverse 0 .. Scope_Stack.Last loop
12733 Scop := Scope_Stack.Table (J).Entity;
12736 and then Base_Type (Scop) = Base_Type (Desig_Type)
12738 Desig_Subtype := Scop;
12741 exit when not Is_Type (Scop);
12744 if Desig_Subtype = Any_Type then
12746 Build_Constrained_Discriminated_Type (Desig_Type);
12753 if Desig_Subtype /= Desig_Type then
12755 -- The Related_Node better be here or else we won't be able
12756 -- to attach new itypes to a node in the tree.
12758 pragma Assert (Present (Related_Node));
12760 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12762 Set_Etype (Itype, Base_Type (Old_Type));
12763 Set_Size_Info (Itype, (Old_Type));
12764 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12765 Set_Depends_On_Private (Itype, Has_Private_Component
12767 Set_Is_Access_Constant (Itype, Is_Access_Constant
12770 -- The new itype needs freezing when it depends on a not frozen
12771 -- type and the enclosing subtype needs freezing.
12773 if Has_Delayed_Freeze (Constrained_Typ)
12774 and then not Is_Frozen (Constrained_Typ)
12776 Conditional_Delay (Itype, Base_Type (Old_Type));
12784 end Build_Constrained_Access_Type;
12786 ----------------------------------
12787 -- Build_Constrained_Array_Type --
12788 ----------------------------------
12790 function Build_Constrained_Array_Type
12791 (Old_Type : Entity_Id) return Entity_Id
12795 Old_Index : Node_Id;
12796 Range_Node : Node_Id;
12797 Constr_List : List_Id;
12799 Need_To_Create_Itype : Boolean := False;
12802 Old_Index := First_Index (Old_Type);
12803 while Present (Old_Index) loop
12804 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12806 if Is_Discriminant (Lo_Expr)
12808 Is_Discriminant (Hi_Expr)
12810 Need_To_Create_Itype := True;
12813 Next_Index (Old_Index);
12816 if Need_To_Create_Itype then
12817 Constr_List := New_List;
12819 Old_Index := First_Index (Old_Type);
12820 while Present (Old_Index) loop
12821 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12823 if Is_Discriminant (Lo_Expr) then
12824 Lo_Expr := Get_Discr_Value (Lo_Expr);
12827 if Is_Discriminant (Hi_Expr) then
12828 Hi_Expr := Get_Discr_Value (Hi_Expr);
12833 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12835 Append (Range_Node, To => Constr_List);
12837 Next_Index (Old_Index);
12840 return Build_Subtype (Old_Type, Constr_List);
12845 end Build_Constrained_Array_Type;
12847 ------------------------------------------
12848 -- Build_Constrained_Discriminated_Type --
12849 ------------------------------------------
12851 function Build_Constrained_Discriminated_Type
12852 (Old_Type : Entity_Id) return Entity_Id
12855 Constr_List : List_Id;
12856 Old_Constraint : Elmt_Id;
12858 Need_To_Create_Itype : Boolean := False;
12861 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12862 while Present (Old_Constraint) loop
12863 Expr := Node (Old_Constraint);
12865 if Is_Discriminant (Expr) then
12866 Need_To_Create_Itype := True;
12869 Next_Elmt (Old_Constraint);
12872 if Need_To_Create_Itype then
12873 Constr_List := New_List;
12875 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12876 while Present (Old_Constraint) loop
12877 Expr := Node (Old_Constraint);
12879 if Is_Discriminant (Expr) then
12880 Expr := Get_Discr_Value (Expr);
12883 Append (New_Copy_Tree (Expr), To => Constr_List);
12885 Next_Elmt (Old_Constraint);
12888 return Build_Subtype (Old_Type, Constr_List);
12893 end Build_Constrained_Discriminated_Type;
12895 -------------------
12896 -- Build_Subtype --
12897 -------------------
12899 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12901 Subtyp_Decl : Node_Id;
12902 Def_Id : Entity_Id;
12903 Btyp : Entity_Id := Base_Type (T);
12906 -- The Related_Node better be here or else we won't be able to
12907 -- attach new itypes to a node in the tree.
12909 pragma Assert (Present (Related_Node));
12911 -- If the view of the component's type is incomplete or private
12912 -- with unknown discriminants, then the constraint must be applied
12913 -- to the full type.
12915 if Has_Unknown_Discriminants (Btyp)
12916 and then Present (Underlying_Type (Btyp))
12918 Btyp := Underlying_Type (Btyp);
12922 Make_Subtype_Indication (Loc,
12923 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12924 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12926 Def_Id := Create_Itype (Ekind (T), Related_Node);
12929 Make_Subtype_Declaration (Loc,
12930 Defining_Identifier => Def_Id,
12931 Subtype_Indication => Indic);
12933 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12935 -- Itypes must be analyzed with checks off (see package Itypes)
12937 Analyze (Subtyp_Decl, Suppress => All_Checks);
12942 ---------------------
12943 -- Get_Discr_Value --
12944 ---------------------
12946 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12951 -- The discriminant may be declared for the type, in which case we
12952 -- find it by iterating over the list of discriminants. If the
12953 -- discriminant is inherited from a parent type, it appears as the
12954 -- corresponding discriminant of the current type. This will be the
12955 -- case when constraining an inherited component whose constraint is
12956 -- given by a discriminant of the parent.
12958 D := First_Discriminant (Typ);
12959 E := First_Elmt (Constraints);
12961 while Present (D) loop
12962 if D = Entity (Discrim)
12963 or else D = CR_Discriminant (Entity (Discrim))
12964 or else Corresponding_Discriminant (D) = Entity (Discrim)
12969 Next_Discriminant (D);
12973 -- The Corresponding_Discriminant mechanism is incomplete, because
12974 -- the correspondence between new and old discriminants is not one
12975 -- to one: one new discriminant can constrain several old ones. In
12976 -- that case, scan sequentially the stored_constraint, the list of
12977 -- discriminants of the parents, and the constraints.
12979 -- Previous code checked for the present of the Stored_Constraint
12980 -- list for the derived type, but did not use it at all. Should it
12981 -- be present when the component is a discriminated task type?
12983 if Is_Derived_Type (Typ)
12984 and then Scope (Entity (Discrim)) = Etype (Typ)
12986 D := First_Discriminant (Etype (Typ));
12987 E := First_Elmt (Constraints);
12988 while Present (D) loop
12989 if D = Entity (Discrim) then
12993 Next_Discriminant (D);
12998 -- Something is wrong if we did not find the value
13000 raise Program_Error;
13001 end Get_Discr_Value;
13003 ---------------------
13004 -- Is_Discriminant --
13005 ---------------------
13007 function Is_Discriminant (Expr : Node_Id) return Boolean is
13008 Discrim_Scope : Entity_Id;
13011 if Denotes_Discriminant (Expr) then
13012 Discrim_Scope := Scope (Entity (Expr));
13014 -- Either we have a reference to one of Typ's discriminants,
13016 pragma Assert (Discrim_Scope = Typ
13018 -- or to the discriminants of the parent type, in the case
13019 -- of a derivation of a tagged type with variants.
13021 or else Discrim_Scope = Etype (Typ)
13022 or else Full_View (Discrim_Scope) = Etype (Typ)
13024 -- or same as above for the case where the discriminants
13025 -- were declared in Typ's private view.
13027 or else (Is_Private_Type (Discrim_Scope)
13028 and then Chars (Discrim_Scope) = Chars (Typ))
13030 -- or else we are deriving from the full view and the
13031 -- discriminant is declared in the private entity.
13033 or else (Is_Private_Type (Typ)
13034 and then Chars (Discrim_Scope) = Chars (Typ))
13036 -- Or we are constrained the corresponding record of a
13037 -- synchronized type that completes a private declaration.
13039 or else (Is_Concurrent_Record_Type (Typ)
13041 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
13043 -- or we have a class-wide type, in which case make sure the
13044 -- discriminant found belongs to the root type.
13046 or else (Is_Class_Wide_Type (Typ)
13047 and then Etype (Typ) = Discrim_Scope));
13052 -- In all other cases we have something wrong
13055 end Is_Discriminant;
13057 -- Start of processing for Constrain_Component_Type
13060 if Nkind (Parent (Comp)) = N_Component_Declaration
13061 and then Comes_From_Source (Parent (Comp))
13062 and then Comes_From_Source
13063 (Subtype_Indication (Component_Definition (Parent (Comp))))
13066 (Subtype_Indication (Component_Definition (Parent (Comp))))
13068 return Compon_Type;
13070 elsif Is_Array_Type (Compon_Type) then
13071 return Build_Constrained_Array_Type (Compon_Type);
13073 elsif Has_Discriminants (Compon_Type) then
13074 return Build_Constrained_Discriminated_Type (Compon_Type);
13076 elsif Is_Access_Type (Compon_Type) then
13077 return Build_Constrained_Access_Type (Compon_Type);
13080 return Compon_Type;
13082 end Constrain_Component_Type;
13084 --------------------------
13085 -- Constrain_Concurrent --
13086 --------------------------
13088 -- For concurrent types, the associated record value type carries the same
13089 -- discriminants, so when we constrain a concurrent type, we must constrain
13090 -- the corresponding record type as well.
13092 procedure Constrain_Concurrent
13093 (Def_Id : in out Entity_Id;
13095 Related_Nod : Node_Id;
13096 Related_Id : Entity_Id;
13097 Suffix : Character)
13099 -- Retrieve Base_Type to ensure getting to the concurrent type in the
13100 -- case of a private subtype (needed when only doing semantic analysis).
13102 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
13106 if Is_Access_Type (T_Ent) then
13107 T_Ent := Designated_Type (T_Ent);
13110 T_Val := Corresponding_Record_Type (T_Ent);
13112 if Present (T_Val) then
13114 if No (Def_Id) then
13115 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13117 -- Elaborate itype now, as it may be used in a subsequent
13118 -- synchronized operation in another scope.
13120 if Nkind (Related_Nod) = N_Full_Type_Declaration then
13121 Build_Itype_Reference (Def_Id, Related_Nod);
13125 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13127 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
13128 Set_Corresponding_Record_Type (Def_Id,
13129 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
13132 -- If there is no associated record, expansion is disabled and this
13133 -- is a generic context. Create a subtype in any case, so that
13134 -- semantic analysis can proceed.
13136 if No (Def_Id) then
13137 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
13140 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
13142 end Constrain_Concurrent;
13144 ------------------------------------
13145 -- Constrain_Corresponding_Record --
13146 ------------------------------------
13148 function Constrain_Corresponding_Record
13149 (Prot_Subt : Entity_Id;
13150 Corr_Rec : Entity_Id;
13151 Related_Nod : Node_Id) return Entity_Id
13153 T_Sub : constant Entity_Id :=
13154 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
13157 Set_Etype (T_Sub, Corr_Rec);
13158 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
13159 Set_Is_Constrained (T_Sub, True);
13160 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
13161 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
13163 if Has_Discriminants (Prot_Subt) then -- False only if errors.
13164 Set_Discriminant_Constraint
13165 (T_Sub, Discriminant_Constraint (Prot_Subt));
13166 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
13167 Create_Constrained_Components
13168 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
13171 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
13173 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
13174 Conditional_Delay (T_Sub, Corr_Rec);
13177 -- This is a component subtype: it will be frozen in the context of
13178 -- the enclosing record's init_proc, so that discriminant references
13179 -- are resolved to discriminals. (Note: we used to skip freezing
13180 -- altogether in that case, which caused errors downstream for
13181 -- components of a bit packed array type).
13183 Set_Has_Delayed_Freeze (T_Sub);
13187 end Constrain_Corresponding_Record;
13189 -----------------------
13190 -- Constrain_Decimal --
13191 -----------------------
13193 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
13194 T : constant Entity_Id := Entity (Subtype_Mark (S));
13195 C : constant Node_Id := Constraint (S);
13196 Loc : constant Source_Ptr := Sloc (C);
13197 Range_Expr : Node_Id;
13198 Digits_Expr : Node_Id;
13203 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
13205 if Nkind (C) = N_Range_Constraint then
13206 Range_Expr := Range_Expression (C);
13207 Digits_Val := Digits_Value (T);
13210 pragma Assert (Nkind (C) = N_Digits_Constraint);
13212 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13214 Digits_Expr := Digits_Expression (C);
13215 Analyze_And_Resolve (Digits_Expr, Any_Integer);
13217 Check_Digits_Expression (Digits_Expr);
13218 Digits_Val := Expr_Value (Digits_Expr);
13220 if Digits_Val > Digits_Value (T) then
13222 ("digits expression is incompatible with subtype", C);
13223 Digits_Val := Digits_Value (T);
13226 if Present (Range_Constraint (C)) then
13227 Range_Expr := Range_Expression (Range_Constraint (C));
13229 Range_Expr := Empty;
13233 Set_Etype (Def_Id, Base_Type (T));
13234 Set_Size_Info (Def_Id, (T));
13235 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13236 Set_Delta_Value (Def_Id, Delta_Value (T));
13237 Set_Scale_Value (Def_Id, Scale_Value (T));
13238 Set_Small_Value (Def_Id, Small_Value (T));
13239 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
13240 Set_Digits_Value (Def_Id, Digits_Val);
13242 -- Manufacture range from given digits value if no range present
13244 if No (Range_Expr) then
13245 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
13249 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
13251 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
13254 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
13255 Set_Discrete_RM_Size (Def_Id);
13257 -- Unconditionally delay the freeze, since we cannot set size
13258 -- information in all cases correctly until the freeze point.
13260 Set_Has_Delayed_Freeze (Def_Id);
13261 end Constrain_Decimal;
13263 ----------------------------------
13264 -- Constrain_Discriminated_Type --
13265 ----------------------------------
13267 procedure Constrain_Discriminated_Type
13268 (Def_Id : Entity_Id;
13270 Related_Nod : Node_Id;
13271 For_Access : Boolean := False)
13273 E : Entity_Id := Entity (Subtype_Mark (S));
13276 procedure Fixup_Bad_Constraint;
13277 -- Called after finding a bad constraint, and after having posted an
13278 -- appropriate error message. The goal is to leave type Def_Id in as
13279 -- reasonable state as possible.
13281 --------------------------
13282 -- Fixup_Bad_Constraint --
13283 --------------------------
13285 procedure Fixup_Bad_Constraint is
13287 -- Set a reasonable Ekind for the entity. For an incomplete type,
13288 -- we can't do much, but for other types, we can set the proper
13289 -- corresponding subtype kind.
13291 if Ekind (T) = E_Incomplete_Type then
13292 Set_Ekind (Def_Id, Ekind (T));
13294 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13297 -- Set Etype to the known type, to reduce chances of cascaded errors
13299 Set_Etype (Def_Id, E);
13300 Set_Error_Posted (Def_Id);
13301 end Fixup_Bad_Constraint;
13306 Constr : Elist_Id := New_Elmt_List;
13308 -- Start of processing for Constrain_Discriminated_Type
13311 C := Constraint (S);
13313 -- A discriminant constraint is only allowed in a subtype indication,
13314 -- after a subtype mark. This subtype mark must denote either a type
13315 -- with discriminants, or an access type whose designated type is a
13316 -- type with discriminants. A discriminant constraint specifies the
13317 -- values of these discriminants (RM 3.7.2(5)).
13319 T := Base_Type (Entity (Subtype_Mark (S)));
13321 if Is_Access_Type (T) then
13322 T := Designated_Type (T);
13325 -- In an instance it may be necessary to retrieve the full view of a
13326 -- type with unknown discriminants, or a full view with defaulted
13327 -- discriminants. In other contexts the constraint is illegal.
13330 and then Is_Private_Type (T)
13331 and then Present (Full_View (T))
13333 (Has_Unknown_Discriminants (T)
13335 (not Has_Discriminants (T)
13336 and then Has_Discriminants (Full_View (T))
13337 and then Present (Discriminant_Default_Value
13338 (First_Discriminant (Full_View (T))))))
13340 T := Full_View (T);
13341 E := Full_View (E);
13344 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal. Avoid
13345 -- generating an error for access-to-incomplete subtypes.
13347 if Ada_Version >= Ada_2005
13348 and then Ekind (T) = E_Incomplete_Type
13349 and then Nkind (Parent (S)) = N_Subtype_Declaration
13350 and then not Is_Itype (Def_Id)
13352 -- A little sanity check: emit an error message if the type has
13353 -- discriminants to begin with. Type T may be a regular incomplete
13354 -- type or imported via a limited with clause.
13356 if Has_Discriminants (T)
13357 or else (From_Limited_With (T)
13358 and then Present (Non_Limited_View (T))
13359 and then Nkind (Parent (Non_Limited_View (T))) =
13360 N_Full_Type_Declaration
13361 and then Present (Discriminant_Specifications
13362 (Parent (Non_Limited_View (T)))))
13365 ("(Ada 2005) incomplete subtype may not be constrained", C);
13367 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13370 Fixup_Bad_Constraint;
13373 -- Check that the type has visible discriminants. The type may be
13374 -- a private type with unknown discriminants whose full view has
13375 -- discriminants which are invisible.
13377 elsif not Has_Discriminants (T)
13379 (Has_Unknown_Discriminants (T)
13380 and then Is_Private_Type (T))
13382 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13383 Fixup_Bad_Constraint;
13386 elsif Is_Constrained (E)
13387 or else (Ekind (E) = E_Class_Wide_Subtype
13388 and then Present (Discriminant_Constraint (E)))
13390 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13391 Fixup_Bad_Constraint;
13395 -- T may be an unconstrained subtype (e.g. a generic actual). Constraint
13396 -- applies to the base type.
13398 T := Base_Type (T);
13400 Constr := Build_Discriminant_Constraints (T, S);
13402 -- If the list returned was empty we had an error in building the
13403 -- discriminant constraint. We have also already signalled an error
13404 -- in the incomplete type case
13406 if Is_Empty_Elmt_List (Constr) then
13407 Fixup_Bad_Constraint;
13411 Build_Discriminated_Subtype (T, Def_Id, Constr, Related_Nod, For_Access);
13412 end Constrain_Discriminated_Type;
13414 ---------------------------
13415 -- Constrain_Enumeration --
13416 ---------------------------
13418 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13419 T : constant Entity_Id := Entity (Subtype_Mark (S));
13420 C : constant Node_Id := Constraint (S);
13423 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13425 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13427 Set_Etype (Def_Id, Base_Type (T));
13428 Set_Size_Info (Def_Id, (T));
13429 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13430 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13432 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13434 Set_Discrete_RM_Size (Def_Id);
13435 end Constrain_Enumeration;
13437 ----------------------
13438 -- Constrain_Float --
13439 ----------------------
13441 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13442 T : constant Entity_Id := Entity (Subtype_Mark (S));
13448 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13450 Set_Etype (Def_Id, Base_Type (T));
13451 Set_Size_Info (Def_Id, (T));
13452 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13454 -- Process the constraint
13456 C := Constraint (S);
13458 -- Digits constraint present
13460 if Nkind (C) = N_Digits_Constraint then
13462 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13463 Check_Restriction (No_Obsolescent_Features, C);
13465 if Warn_On_Obsolescent_Feature then
13467 ("subtype digits constraint is an " &
13468 "obsolescent feature (RM J.3(8))?j?", C);
13471 D := Digits_Expression (C);
13472 Analyze_And_Resolve (D, Any_Integer);
13473 Check_Digits_Expression (D);
13474 Set_Digits_Value (Def_Id, Expr_Value (D));
13476 -- Check that digits value is in range. Obviously we can do this
13477 -- at compile time, but it is strictly a runtime check, and of
13478 -- course there is an ACVC test that checks this.
13480 if Digits_Value (Def_Id) > Digits_Value (T) then
13481 Error_Msg_Uint_1 := Digits_Value (T);
13482 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13484 Make_Raise_Constraint_Error (Sloc (D),
13485 Reason => CE_Range_Check_Failed);
13486 Insert_Action (Declaration_Node (Def_Id), Rais);
13489 C := Range_Constraint (C);
13491 -- No digits constraint present
13494 Set_Digits_Value (Def_Id, Digits_Value (T));
13497 -- Range constraint present
13499 if Nkind (C) = N_Range_Constraint then
13500 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13502 -- No range constraint present
13505 pragma Assert (No (C));
13506 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13509 Set_Is_Constrained (Def_Id);
13510 end Constrain_Float;
13512 ---------------------
13513 -- Constrain_Index --
13514 ---------------------
13516 procedure Constrain_Index
13519 Related_Nod : Node_Id;
13520 Related_Id : Entity_Id;
13521 Suffix : Character;
13522 Suffix_Index : Nat)
13524 Def_Id : Entity_Id;
13525 R : Node_Id := Empty;
13526 T : constant Entity_Id := Etype (Index);
13530 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13531 Set_Etype (Def_Id, Base_Type (T));
13533 if Nkind (S) = N_Range
13535 (Nkind (S) = N_Attribute_Reference
13536 and then Attribute_Name (S) = Name_Range)
13538 -- A Range attribute will be transformed into N_Range by Resolve
13544 Process_Range_Expr_In_Decl (R, T);
13546 if not Error_Posted (S)
13548 (Nkind (S) /= N_Range
13549 or else not Covers (T, (Etype (Low_Bound (S))))
13550 or else not Covers (T, (Etype (High_Bound (S)))))
13552 if Base_Type (T) /= Any_Type
13553 and then Etype (Low_Bound (S)) /= Any_Type
13554 and then Etype (High_Bound (S)) /= Any_Type
13556 Error_Msg_N ("range expected", S);
13560 elsif Nkind (S) = N_Subtype_Indication then
13562 -- The parser has verified that this is a discrete indication
13564 Resolve_Discrete_Subtype_Indication (S, T);
13565 Bad_Predicated_Subtype_Use
13566 ("subtype& has predicate, not allowed in index constraint",
13567 S, Entity (Subtype_Mark (S)));
13569 R := Range_Expression (Constraint (S));
13571 -- Capture values of bounds and generate temporaries for them if
13572 -- needed, since checks may cause duplication of the expressions
13573 -- which must not be reevaluated.
13575 -- The forced evaluation removes side effects from expressions, which
13576 -- should occur also in GNATprove mode. Otherwise, we end up with
13577 -- unexpected insertions of actions at places where this is not
13578 -- supposed to occur, e.g. on default parameters of a call.
13580 if Expander_Active or GNATprove_Mode then
13582 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13584 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13587 elsif Nkind (S) = N_Discriminant_Association then
13589 -- Syntactically valid in subtype indication
13591 Error_Msg_N ("invalid index constraint", S);
13592 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13595 -- Subtype_Mark case, no anonymous subtypes to construct
13600 if Is_Entity_Name (S) then
13601 if not Is_Type (Entity (S)) then
13602 Error_Msg_N ("expect subtype mark for index constraint", S);
13604 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13605 Wrong_Type (S, Base_Type (T));
13607 -- Check error of subtype with predicate in index constraint
13610 Bad_Predicated_Subtype_Use
13611 ("subtype& has predicate, not allowed in index constraint",
13618 Error_Msg_N ("invalid index constraint", S);
13619 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13624 -- Complete construction of the Itype
13626 if Is_Modular_Integer_Type (T) then
13627 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13629 elsif Is_Integer_Type (T) then
13630 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13633 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13634 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13635 Set_First_Literal (Def_Id, First_Literal (T));
13638 Set_Size_Info (Def_Id, (T));
13639 Set_RM_Size (Def_Id, RM_Size (T));
13640 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13642 Set_Scalar_Range (Def_Id, R);
13644 Set_Etype (S, Def_Id);
13645 Set_Discrete_RM_Size (Def_Id);
13646 end Constrain_Index;
13648 -----------------------
13649 -- Constrain_Integer --
13650 -----------------------
13652 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13653 T : constant Entity_Id := Entity (Subtype_Mark (S));
13654 C : constant Node_Id := Constraint (S);
13657 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13659 if Is_Modular_Integer_Type (T) then
13660 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13662 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13665 Set_Etype (Def_Id, Base_Type (T));
13666 Set_Size_Info (Def_Id, (T));
13667 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13668 Set_Discrete_RM_Size (Def_Id);
13669 end Constrain_Integer;
13671 ------------------------------
13672 -- Constrain_Ordinary_Fixed --
13673 ------------------------------
13675 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13676 T : constant Entity_Id := Entity (Subtype_Mark (S));
13682 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13683 Set_Etype (Def_Id, Base_Type (T));
13684 Set_Size_Info (Def_Id, (T));
13685 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13686 Set_Small_Value (Def_Id, Small_Value (T));
13688 -- Process the constraint
13690 C := Constraint (S);
13692 -- Delta constraint present
13694 if Nkind (C) = N_Delta_Constraint then
13696 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13697 Check_Restriction (No_Obsolescent_Features, C);
13699 if Warn_On_Obsolescent_Feature then
13701 ("subtype delta constraint is an " &
13702 "obsolescent feature (RM J.3(7))?j?");
13705 D := Delta_Expression (C);
13706 Analyze_And_Resolve (D, Any_Real);
13707 Check_Delta_Expression (D);
13708 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13710 -- Check that delta value is in range. Obviously we can do this
13711 -- at compile time, but it is strictly a runtime check, and of
13712 -- course there is an ACVC test that checks this.
13714 if Delta_Value (Def_Id) < Delta_Value (T) then
13715 Error_Msg_N ("??delta value is too small", D);
13717 Make_Raise_Constraint_Error (Sloc (D),
13718 Reason => CE_Range_Check_Failed);
13719 Insert_Action (Declaration_Node (Def_Id), Rais);
13722 C := Range_Constraint (C);
13724 -- No delta constraint present
13727 Set_Delta_Value (Def_Id, Delta_Value (T));
13730 -- Range constraint present
13732 if Nkind (C) = N_Range_Constraint then
13733 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13735 -- No range constraint present
13738 pragma Assert (No (C));
13739 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13742 Set_Discrete_RM_Size (Def_Id);
13744 -- Unconditionally delay the freeze, since we cannot set size
13745 -- information in all cases correctly until the freeze point.
13747 Set_Has_Delayed_Freeze (Def_Id);
13748 end Constrain_Ordinary_Fixed;
13750 -----------------------
13751 -- Contain_Interface --
13752 -----------------------
13754 function Contain_Interface
13755 (Iface : Entity_Id;
13756 Ifaces : Elist_Id) return Boolean
13758 Iface_Elmt : Elmt_Id;
13761 if Present (Ifaces) then
13762 Iface_Elmt := First_Elmt (Ifaces);
13763 while Present (Iface_Elmt) loop
13764 if Node (Iface_Elmt) = Iface then
13768 Next_Elmt (Iface_Elmt);
13773 end Contain_Interface;
13775 ---------------------------
13776 -- Convert_Scalar_Bounds --
13777 ---------------------------
13779 procedure Convert_Scalar_Bounds
13781 Parent_Type : Entity_Id;
13782 Derived_Type : Entity_Id;
13785 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13792 -- Defend against previous errors
13794 if No (Scalar_Range (Derived_Type)) then
13795 Check_Error_Detected;
13799 Lo := Build_Scalar_Bound
13800 (Type_Low_Bound (Derived_Type),
13801 Parent_Type, Implicit_Base);
13803 Hi := Build_Scalar_Bound
13804 (Type_High_Bound (Derived_Type),
13805 Parent_Type, Implicit_Base);
13812 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13814 Set_Parent (Rng, N);
13815 Set_Scalar_Range (Derived_Type, Rng);
13817 -- Analyze the bounds
13819 Analyze_And_Resolve (Lo, Implicit_Base);
13820 Analyze_And_Resolve (Hi, Implicit_Base);
13822 -- Analyze the range itself, except that we do not analyze it if
13823 -- the bounds are real literals, and we have a fixed-point type.
13824 -- The reason for this is that we delay setting the bounds in this
13825 -- case till we know the final Small and Size values (see circuit
13826 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13828 if Is_Fixed_Point_Type (Parent_Type)
13829 and then Nkind (Lo) = N_Real_Literal
13830 and then Nkind (Hi) = N_Real_Literal
13834 -- Here we do the analysis of the range
13836 -- Note: we do this manually, since if we do a normal Analyze and
13837 -- Resolve call, there are problems with the conversions used for
13838 -- the derived type range.
13841 Set_Etype (Rng, Implicit_Base);
13842 Set_Analyzed (Rng, True);
13844 end Convert_Scalar_Bounds;
13846 -------------------
13847 -- Copy_And_Swap --
13848 -------------------
13850 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13852 -- Initialize new full declaration entity by copying the pertinent
13853 -- fields of the corresponding private declaration entity.
13855 -- We temporarily set Ekind to a value appropriate for a type to
13856 -- avoid assert failures in Einfo from checking for setting type
13857 -- attributes on something that is not a type. Ekind (Priv) is an
13858 -- appropriate choice, since it allowed the attributes to be set
13859 -- in the first place. This Ekind value will be modified later.
13861 Set_Ekind (Full, Ekind (Priv));
13863 -- Also set Etype temporarily to Any_Type, again, in the absence
13864 -- of errors, it will be properly reset, and if there are errors,
13865 -- then we want a value of Any_Type to remain.
13867 Set_Etype (Full, Any_Type);
13869 -- Now start copying attributes
13871 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13873 if Has_Discriminants (Full) then
13874 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13875 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13878 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13879 Set_Homonym (Full, Homonym (Priv));
13880 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13881 Set_Is_Public (Full, Is_Public (Priv));
13882 Set_Is_Pure (Full, Is_Pure (Priv));
13883 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13884 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13885 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13886 Set_Has_Pragma_Unreferenced_Objects
13887 (Full, Has_Pragma_Unreferenced_Objects
13890 Conditional_Delay (Full, Priv);
13892 if Is_Tagged_Type (Full) then
13893 Set_Direct_Primitive_Operations
13894 (Full, Direct_Primitive_Operations (Priv));
13895 Set_No_Tagged_Streams_Pragma
13896 (Full, No_Tagged_Streams_Pragma (Priv));
13898 if Is_Base_Type (Priv) then
13899 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13903 Set_Is_Volatile (Full, Is_Volatile (Priv));
13904 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13905 Set_Scope (Full, Scope (Priv));
13906 Set_Next_Entity (Full, Next_Entity (Priv));
13907 Set_First_Entity (Full, First_Entity (Priv));
13908 Set_Last_Entity (Full, Last_Entity (Priv));
13910 -- If access types have been recorded for later handling, keep them in
13911 -- the full view so that they get handled when the full view freeze
13912 -- node is expanded.
13914 if Present (Freeze_Node (Priv))
13915 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13917 Ensure_Freeze_Node (Full);
13918 Set_Access_Types_To_Process
13919 (Freeze_Node (Full),
13920 Access_Types_To_Process (Freeze_Node (Priv)));
13923 -- Swap the two entities. Now Private is the full type entity and Full
13924 -- is the private one. They will be swapped back at the end of the
13925 -- private part. This swapping ensures that the entity that is visible
13926 -- in the private part is the full declaration.
13928 Exchange_Entities (Priv, Full);
13929 Append_Entity (Full, Scope (Full));
13932 -------------------------------------
13933 -- Copy_Array_Base_Type_Attributes --
13934 -------------------------------------
13936 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13938 Set_Component_Alignment (T1, Component_Alignment (T2));
13939 Set_Component_Type (T1, Component_Type (T2));
13940 Set_Component_Size (T1, Component_Size (T2));
13941 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13942 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13943 Propagate_Concurrent_Flags (T1, T2);
13944 Set_Is_Packed (T1, Is_Packed (T2));
13945 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13946 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13947 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13948 end Copy_Array_Base_Type_Attributes;
13950 -----------------------------------
13951 -- Copy_Array_Subtype_Attributes --
13952 -----------------------------------
13954 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13956 Set_Size_Info (T1, T2);
13958 Set_First_Index (T1, First_Index (T2));
13959 Set_Is_Aliased (T1, Is_Aliased (T2));
13960 Set_Is_Volatile (T1, Is_Volatile (T2));
13961 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13962 Set_Is_Constrained (T1, Is_Constrained (T2));
13963 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13964 Inherit_Rep_Item_Chain (T1, T2);
13965 Set_Convention (T1, Convention (T2));
13966 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13967 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13968 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13969 end Copy_Array_Subtype_Attributes;
13971 -----------------------------------
13972 -- Create_Constrained_Components --
13973 -----------------------------------
13975 procedure Create_Constrained_Components
13977 Decl_Node : Node_Id;
13979 Constraints : Elist_Id)
13981 Loc : constant Source_Ptr := Sloc (Subt);
13982 Comp_List : constant Elist_Id := New_Elmt_List;
13983 Parent_Type : constant Entity_Id := Etype (Typ);
13984 Assoc_List : constant List_Id := New_List;
13985 Discr_Val : Elmt_Id;
13989 Is_Static : Boolean := True;
13991 procedure Collect_Fixed_Components (Typ : Entity_Id);
13992 -- Collect parent type components that do not appear in a variant part
13994 procedure Create_All_Components;
13995 -- Iterate over Comp_List to create the components of the subtype
13997 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13998 -- Creates a new component from Old_Compon, copying all the fields from
13999 -- it, including its Etype, inserts the new component in the Subt entity
14000 -- chain and returns the new component.
14002 function Is_Variant_Record (T : Entity_Id) return Boolean;
14003 -- If true, and discriminants are static, collect only components from
14004 -- variants selected by discriminant values.
14006 ------------------------------
14007 -- Collect_Fixed_Components --
14008 ------------------------------
14010 procedure Collect_Fixed_Components (Typ : Entity_Id) is
14012 -- Build association list for discriminants, and find components of the
14013 -- variant part selected by the values of the discriminants.
14015 Old_C := First_Discriminant (Typ);
14016 Discr_Val := First_Elmt (Constraints);
14017 while Present (Old_C) loop
14018 Append_To (Assoc_List,
14019 Make_Component_Association (Loc,
14020 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
14021 Expression => New_Copy (Node (Discr_Val))));
14023 Next_Elmt (Discr_Val);
14024 Next_Discriminant (Old_C);
14027 -- The tag and the possible parent component are unconditionally in
14030 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
14031 Old_C := First_Component (Typ);
14032 while Present (Old_C) loop
14033 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
14034 Append_Elmt (Old_C, Comp_List);
14037 Next_Component (Old_C);
14040 end Collect_Fixed_Components;
14042 ---------------------------
14043 -- Create_All_Components --
14044 ---------------------------
14046 procedure Create_All_Components is
14050 Comp := First_Elmt (Comp_List);
14051 while Present (Comp) loop
14052 Old_C := Node (Comp);
14053 New_C := Create_Component (Old_C);
14057 Constrain_Component_Type
14058 (Old_C, Subt, Decl_Node, Typ, Constraints));
14059 Set_Is_Public (New_C, Is_Public (Subt));
14063 end Create_All_Components;
14065 ----------------------
14066 -- Create_Component --
14067 ----------------------
14069 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
14070 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
14073 if Ekind (Old_Compon) = E_Discriminant
14074 and then Is_Completely_Hidden (Old_Compon)
14076 -- This is a shadow discriminant created for a discriminant of
14077 -- the parent type, which needs to be present in the subtype.
14078 -- Give the shadow discriminant an internal name that cannot
14079 -- conflict with that of visible components.
14081 Set_Chars (New_Compon, New_Internal_Name ('C'));
14084 -- Set the parent so we have a proper link for freezing etc. This is
14085 -- not a real parent pointer, since of course our parent does not own
14086 -- up to us and reference us, we are an illegitimate child of the
14087 -- original parent.
14089 Set_Parent (New_Compon, Parent (Old_Compon));
14091 -- If the old component's Esize was already determined and is a
14092 -- static value, then the new component simply inherits it. Otherwise
14093 -- the old component's size may require run-time determination, but
14094 -- the new component's size still might be statically determinable
14095 -- (if, for example it has a static constraint). In that case we want
14096 -- Layout_Type to recompute the component's size, so we reset its
14097 -- size and positional fields.
14099 if Frontend_Layout_On_Target
14100 and then not Known_Static_Esize (Old_Compon)
14102 Set_Esize (New_Compon, Uint_0);
14103 Init_Normalized_First_Bit (New_Compon);
14104 Init_Normalized_Position (New_Compon);
14105 Init_Normalized_Position_Max (New_Compon);
14108 -- We do not want this node marked as Comes_From_Source, since
14109 -- otherwise it would get first class status and a separate cross-
14110 -- reference line would be generated. Illegitimate children do not
14111 -- rate such recognition.
14113 Set_Comes_From_Source (New_Compon, False);
14115 -- But it is a real entity, and a birth certificate must be properly
14116 -- registered by entering it into the entity list.
14118 Enter_Name (New_Compon);
14121 end Create_Component;
14123 -----------------------
14124 -- Is_Variant_Record --
14125 -----------------------
14127 function Is_Variant_Record (T : Entity_Id) return Boolean is
14129 return Nkind (Parent (T)) = N_Full_Type_Declaration
14130 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
14131 and then Present (Component_List (Type_Definition (Parent (T))))
14134 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
14135 end Is_Variant_Record;
14137 -- Start of processing for Create_Constrained_Components
14140 pragma Assert (Subt /= Base_Type (Subt));
14141 pragma Assert (Typ = Base_Type (Typ));
14143 Set_First_Entity (Subt, Empty);
14144 Set_Last_Entity (Subt, Empty);
14146 -- Check whether constraint is fully static, in which case we can
14147 -- optimize the list of components.
14149 Discr_Val := First_Elmt (Constraints);
14150 while Present (Discr_Val) loop
14151 if not Is_OK_Static_Expression (Node (Discr_Val)) then
14152 Is_Static := False;
14156 Next_Elmt (Discr_Val);
14159 Set_Has_Static_Discriminants (Subt, Is_Static);
14163 -- Inherit the discriminants of the parent type
14165 Add_Discriminants : declare
14171 Old_C := First_Discriminant (Typ);
14173 while Present (Old_C) loop
14174 Num_Disc := Num_Disc + 1;
14175 New_C := Create_Component (Old_C);
14176 Set_Is_Public (New_C, Is_Public (Subt));
14177 Next_Discriminant (Old_C);
14180 -- For an untagged derived subtype, the number of discriminants may
14181 -- be smaller than the number of inherited discriminants, because
14182 -- several of them may be renamed by a single new discriminant or
14183 -- constrained. In this case, add the hidden discriminants back into
14184 -- the subtype, because they need to be present if the optimizer of
14185 -- the GCC 4.x back-end decides to break apart assignments between
14186 -- objects using the parent view into member-wise assignments.
14190 if Is_Derived_Type (Typ)
14191 and then not Is_Tagged_Type (Typ)
14193 Old_C := First_Stored_Discriminant (Typ);
14195 while Present (Old_C) loop
14196 Num_Gird := Num_Gird + 1;
14197 Next_Stored_Discriminant (Old_C);
14201 if Num_Gird > Num_Disc then
14203 -- Find out multiple uses of new discriminants, and add hidden
14204 -- components for the extra renamed discriminants. We recognize
14205 -- multiple uses through the Corresponding_Discriminant of a
14206 -- new discriminant: if it constrains several old discriminants,
14207 -- this field points to the last one in the parent type. The
14208 -- stored discriminants of the derived type have the same name
14209 -- as those of the parent.
14213 New_Discr : Entity_Id;
14214 Old_Discr : Entity_Id;
14217 Constr := First_Elmt (Stored_Constraint (Typ));
14218 Old_Discr := First_Stored_Discriminant (Typ);
14219 while Present (Constr) loop
14220 if Is_Entity_Name (Node (Constr))
14221 and then Ekind (Entity (Node (Constr))) = E_Discriminant
14223 New_Discr := Entity (Node (Constr));
14225 if Chars (Corresponding_Discriminant (New_Discr)) /=
14228 -- The new discriminant has been used to rename a
14229 -- subsequent old discriminant. Introduce a shadow
14230 -- component for the current old discriminant.
14232 New_C := Create_Component (Old_Discr);
14233 Set_Original_Record_Component (New_C, Old_Discr);
14237 -- The constraint has eliminated the old discriminant.
14238 -- Introduce a shadow component.
14240 New_C := Create_Component (Old_Discr);
14241 Set_Original_Record_Component (New_C, Old_Discr);
14244 Next_Elmt (Constr);
14245 Next_Stored_Discriminant (Old_Discr);
14249 end Add_Discriminants;
14252 and then Is_Variant_Record (Typ)
14254 Collect_Fixed_Components (Typ);
14256 Gather_Components (
14258 Component_List (Type_Definition (Parent (Typ))),
14259 Governed_By => Assoc_List,
14261 Report_Errors => Errors);
14262 pragma Assert (not Errors
14263 or else Serious_Errors_Detected > 0);
14265 Create_All_Components;
14267 -- If the subtype declaration is created for a tagged type derivation
14268 -- with constraints, we retrieve the record definition of the parent
14269 -- type to select the components of the proper variant.
14272 and then Is_Tagged_Type (Typ)
14273 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
14275 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
14276 and then Is_Variant_Record (Parent_Type)
14278 Collect_Fixed_Components (Typ);
14282 Component_List (Type_Definition (Parent (Parent_Type))),
14283 Governed_By => Assoc_List,
14285 Report_Errors => Errors);
14287 -- Note: previously there was a check at this point that no errors
14288 -- were detected. As a consequence of AI05-220 there may be an error
14289 -- if an inherited discriminant that controls a variant has a non-
14290 -- static constraint.
14292 -- If the tagged derivation has a type extension, collect all the
14293 -- new components therein.
14295 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14297 Old_C := First_Component (Typ);
14298 while Present (Old_C) loop
14299 if Original_Record_Component (Old_C) = Old_C
14300 and then Chars (Old_C) /= Name_uTag
14301 and then Chars (Old_C) /= Name_uParent
14303 Append_Elmt (Old_C, Comp_List);
14306 Next_Component (Old_C);
14310 Create_All_Components;
14313 -- If discriminants are not static, or if this is a multi-level type
14314 -- extension, we have to include all components of the parent type.
14316 Old_C := First_Component (Typ);
14317 while Present (Old_C) loop
14318 New_C := Create_Component (Old_C);
14322 Constrain_Component_Type
14323 (Old_C, Subt, Decl_Node, Typ, Constraints));
14324 Set_Is_Public (New_C, Is_Public (Subt));
14326 Next_Component (Old_C);
14331 end Create_Constrained_Components;
14333 ------------------------------------------
14334 -- Decimal_Fixed_Point_Type_Declaration --
14335 ------------------------------------------
14337 procedure Decimal_Fixed_Point_Type_Declaration
14341 Loc : constant Source_Ptr := Sloc (Def);
14342 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14343 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14344 Implicit_Base : Entity_Id;
14351 Check_SPARK_05_Restriction
14352 ("decimal fixed point type is not allowed", Def);
14353 Check_Restriction (No_Fixed_Point, Def);
14355 -- Create implicit base type
14358 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14359 Set_Etype (Implicit_Base, Implicit_Base);
14361 -- Analyze and process delta expression
14363 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14365 Check_Delta_Expression (Delta_Expr);
14366 Delta_Val := Expr_Value_R (Delta_Expr);
14368 -- Check delta is power of 10, and determine scale value from it
14374 Scale_Val := Uint_0;
14377 if Val < Ureal_1 then
14378 while Val < Ureal_1 loop
14379 Val := Val * Ureal_10;
14380 Scale_Val := Scale_Val + 1;
14383 if Scale_Val > 18 then
14384 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14385 Scale_Val := UI_From_Int (+18);
14389 while Val > Ureal_1 loop
14390 Val := Val / Ureal_10;
14391 Scale_Val := Scale_Val - 1;
14394 if Scale_Val < -18 then
14395 Error_Msg_N ("scale is less than minimum value of -18", Def);
14396 Scale_Val := UI_From_Int (-18);
14400 if Val /= Ureal_1 then
14401 Error_Msg_N ("delta expression must be a power of 10", Def);
14402 Delta_Val := Ureal_10 ** (-Scale_Val);
14406 -- Set delta, scale and small (small = delta for decimal type)
14408 Set_Delta_Value (Implicit_Base, Delta_Val);
14409 Set_Scale_Value (Implicit_Base, Scale_Val);
14410 Set_Small_Value (Implicit_Base, Delta_Val);
14412 -- Analyze and process digits expression
14414 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14415 Check_Digits_Expression (Digs_Expr);
14416 Digs_Val := Expr_Value (Digs_Expr);
14418 if Digs_Val > 18 then
14419 Digs_Val := UI_From_Int (+18);
14420 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14423 Set_Digits_Value (Implicit_Base, Digs_Val);
14424 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14426 -- Set range of base type from digits value for now. This will be
14427 -- expanded to represent the true underlying base range by Freeze.
14429 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14431 -- Note: We leave size as zero for now, size will be set at freeze
14432 -- time. We have to do this for ordinary fixed-point, because the size
14433 -- depends on the specified small, and we might as well do the same for
14434 -- decimal fixed-point.
14436 pragma Assert (Esize (Implicit_Base) = Uint_0);
14438 -- If there are bounds given in the declaration use them as the
14439 -- bounds of the first named subtype.
14441 if Present (Real_Range_Specification (Def)) then
14443 RRS : constant Node_Id := Real_Range_Specification (Def);
14444 Low : constant Node_Id := Low_Bound (RRS);
14445 High : constant Node_Id := High_Bound (RRS);
14450 Analyze_And_Resolve (Low, Any_Real);
14451 Analyze_And_Resolve (High, Any_Real);
14452 Check_Real_Bound (Low);
14453 Check_Real_Bound (High);
14454 Low_Val := Expr_Value_R (Low);
14455 High_Val := Expr_Value_R (High);
14457 if Low_Val < (-Bound_Val) then
14459 ("range low bound too small for digits value", Low);
14460 Low_Val := -Bound_Val;
14463 if High_Val > Bound_Val then
14465 ("range high bound too large for digits value", High);
14466 High_Val := Bound_Val;
14469 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14472 -- If no explicit range, use range that corresponds to given
14473 -- digits value. This will end up as the final range for the
14477 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14480 -- Complete entity for first subtype. The inheritance of the rep item
14481 -- chain ensures that SPARK-related pragmas are not clobbered when the
14482 -- decimal fixed point type acts as a full view of a private type.
14484 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14485 Set_Etype (T, Implicit_Base);
14486 Set_Size_Info (T, Implicit_Base);
14487 Inherit_Rep_Item_Chain (T, Implicit_Base);
14488 Set_Digits_Value (T, Digs_Val);
14489 Set_Delta_Value (T, Delta_Val);
14490 Set_Small_Value (T, Delta_Val);
14491 Set_Scale_Value (T, Scale_Val);
14492 Set_Is_Constrained (T);
14493 end Decimal_Fixed_Point_Type_Declaration;
14495 -----------------------------------
14496 -- Derive_Progenitor_Subprograms --
14497 -----------------------------------
14499 procedure Derive_Progenitor_Subprograms
14500 (Parent_Type : Entity_Id;
14501 Tagged_Type : Entity_Id)
14506 Iface_Elmt : Elmt_Id;
14507 Iface_Subp : Entity_Id;
14508 New_Subp : Entity_Id := Empty;
14509 Prim_Elmt : Elmt_Id;
14514 pragma Assert (Ada_Version >= Ada_2005
14515 and then Is_Record_Type (Tagged_Type)
14516 and then Is_Tagged_Type (Tagged_Type)
14517 and then Has_Interfaces (Tagged_Type));
14519 -- Step 1: Transfer to the full-view primitives associated with the
14520 -- partial-view that cover interface primitives. Conceptually this
14521 -- work should be done later by Process_Full_View; done here to
14522 -- simplify its implementation at later stages. It can be safely
14523 -- done here because interfaces must be visible in the partial and
14524 -- private view (RM 7.3(7.3/2)).
14526 -- Small optimization: This work is only required if the parent may
14527 -- have entities whose Alias attribute reference an interface primitive.
14528 -- Such a situation may occur if the parent is an abstract type and the
14529 -- primitive has not been yet overridden or if the parent is a generic
14530 -- formal type covering interfaces.
14532 -- If the tagged type is not abstract, it cannot have abstract
14533 -- primitives (the only entities in the list of primitives of
14534 -- non-abstract tagged types that can reference abstract primitives
14535 -- through its Alias attribute are the internal entities that have
14536 -- attribute Interface_Alias, and these entities are generated later
14537 -- by Add_Internal_Interface_Entities).
14539 if In_Private_Part (Current_Scope)
14540 and then (Is_Abstract_Type (Parent_Type)
14542 Is_Generic_Type (Parent_Type))
14544 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14545 while Present (Elmt) loop
14546 Subp := Node (Elmt);
14548 -- At this stage it is not possible to have entities in the list
14549 -- of primitives that have attribute Interface_Alias.
14551 pragma Assert (No (Interface_Alias (Subp)));
14553 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14555 if Is_Interface (Typ) then
14556 E := Find_Primitive_Covering_Interface
14557 (Tagged_Type => Tagged_Type,
14558 Iface_Prim => Subp);
14561 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14563 Replace_Elmt (Elmt, E);
14564 Remove_Homonym (Subp);
14572 -- Step 2: Add primitives of progenitors that are not implemented by
14573 -- parents of Tagged_Type.
14575 if Present (Interfaces (Base_Type (Tagged_Type))) then
14576 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14577 while Present (Iface_Elmt) loop
14578 Iface := Node (Iface_Elmt);
14580 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14581 while Present (Prim_Elmt) loop
14582 Iface_Subp := Node (Prim_Elmt);
14584 -- Exclude derivation of predefined primitives except those
14585 -- that come from source, or are inherited from one that comes
14586 -- from source. Required to catch declarations of equality
14587 -- operators of interfaces. For example:
14589 -- type Iface is interface;
14590 -- function "=" (Left, Right : Iface) return Boolean;
14592 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14593 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14595 E := Find_Primitive_Covering_Interface
14596 (Tagged_Type => Tagged_Type,
14597 Iface_Prim => Iface_Subp);
14599 -- If not found we derive a new primitive leaving its alias
14600 -- attribute referencing the interface primitive.
14604 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14606 -- Ada 2012 (AI05-0197): If the covering primitive's name
14607 -- differs from the name of the interface primitive then it
14608 -- is a private primitive inherited from a parent type. In
14609 -- such case, given that Tagged_Type covers the interface,
14610 -- the inherited private primitive becomes visible. For such
14611 -- purpose we add a new entity that renames the inherited
14612 -- private primitive.
14614 elsif Chars (E) /= Chars (Iface_Subp) then
14615 pragma Assert (Has_Suffix (E, 'P'));
14617 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14618 Set_Alias (New_Subp, E);
14619 Set_Is_Abstract_Subprogram (New_Subp,
14620 Is_Abstract_Subprogram (E));
14622 -- Propagate to the full view interface entities associated
14623 -- with the partial view.
14625 elsif In_Private_Part (Current_Scope)
14626 and then Present (Alias (E))
14627 and then Alias (E) = Iface_Subp
14629 List_Containing (Parent (E)) /=
14630 Private_Declarations
14632 (Unit_Declaration_Node (Current_Scope)))
14634 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14638 Next_Elmt (Prim_Elmt);
14641 Next_Elmt (Iface_Elmt);
14644 end Derive_Progenitor_Subprograms;
14646 -----------------------
14647 -- Derive_Subprogram --
14648 -----------------------
14650 procedure Derive_Subprogram
14651 (New_Subp : out Entity_Id;
14652 Parent_Subp : Entity_Id;
14653 Derived_Type : Entity_Id;
14654 Parent_Type : Entity_Id;
14655 Actual_Subp : Entity_Id := Empty)
14657 Formal : Entity_Id;
14658 -- Formal parameter of parent primitive operation
14660 Formal_Of_Actual : Entity_Id;
14661 -- Formal parameter of actual operation, when the derivation is to
14662 -- create a renaming for a primitive operation of an actual in an
14665 New_Formal : Entity_Id;
14666 -- Formal of inherited operation
14668 Visible_Subp : Entity_Id := Parent_Subp;
14670 function Is_Private_Overriding return Boolean;
14671 -- If Subp is a private overriding of a visible operation, the inherited
14672 -- operation derives from the overridden op (even though its body is the
14673 -- overriding one) and the inherited operation is visible now. See
14674 -- sem_disp to see the full details of the handling of the overridden
14675 -- subprogram, which is removed from the list of primitive operations of
14676 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14677 -- and used to diagnose abstract operations that need overriding in the
14680 procedure Replace_Type (Id, New_Id : Entity_Id);
14681 -- When the type is an anonymous access type, create a new access type
14682 -- designating the derived type.
14684 procedure Set_Derived_Name;
14685 -- This procedure sets the appropriate Chars name for New_Subp. This
14686 -- is normally just a copy of the parent name. An exception arises for
14687 -- type support subprograms, where the name is changed to reflect the
14688 -- name of the derived type, e.g. if type foo is derived from type bar,
14689 -- then a procedure barDA is derived with a name fooDA.
14691 ---------------------------
14692 -- Is_Private_Overriding --
14693 ---------------------------
14695 function Is_Private_Overriding return Boolean is
14699 -- If the parent is not a dispatching operation there is no
14700 -- need to investigate overridings
14702 if not Is_Dispatching_Operation (Parent_Subp) then
14706 -- The visible operation that is overridden is a homonym of the
14707 -- parent subprogram. We scan the homonym chain to find the one
14708 -- whose alias is the subprogram we are deriving.
14710 Prev := Current_Entity (Parent_Subp);
14711 while Present (Prev) loop
14712 if Ekind (Prev) = Ekind (Parent_Subp)
14713 and then Alias (Prev) = Parent_Subp
14714 and then Scope (Parent_Subp) = Scope (Prev)
14715 and then not Is_Hidden (Prev)
14717 Visible_Subp := Prev;
14721 Prev := Homonym (Prev);
14725 end Is_Private_Overriding;
14731 procedure Replace_Type (Id, New_Id : Entity_Id) is
14732 Id_Type : constant Entity_Id := Etype (Id);
14733 Acc_Type : Entity_Id;
14734 Par : constant Node_Id := Parent (Derived_Type);
14737 -- When the type is an anonymous access type, create a new access
14738 -- type designating the derived type. This itype must be elaborated
14739 -- at the point of the derivation, not on subsequent calls that may
14740 -- be out of the proper scope for Gigi, so we insert a reference to
14741 -- it after the derivation.
14743 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14745 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14748 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14749 and then Present (Full_View (Desig_Typ))
14750 and then not Is_Private_Type (Parent_Type)
14752 Desig_Typ := Full_View (Desig_Typ);
14755 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14757 -- Ada 2005 (AI-251): Handle also derivations of abstract
14758 -- interface primitives.
14760 or else (Is_Interface (Desig_Typ)
14761 and then not Is_Class_Wide_Type (Desig_Typ))
14763 Acc_Type := New_Copy (Id_Type);
14764 Set_Etype (Acc_Type, Acc_Type);
14765 Set_Scope (Acc_Type, New_Subp);
14767 -- Set size of anonymous access type. If we have an access
14768 -- to an unconstrained array, this is a fat pointer, so it
14769 -- is sizes at twice addtress size.
14771 if Is_Array_Type (Desig_Typ)
14772 and then not Is_Constrained (Desig_Typ)
14774 Init_Size (Acc_Type, 2 * System_Address_Size);
14776 -- Other cases use a thin pointer
14779 Init_Size (Acc_Type, System_Address_Size);
14782 -- Set remaining characterstics of anonymous access type
14784 Init_Alignment (Acc_Type);
14785 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14787 Set_Etype (New_Id, Acc_Type);
14788 Set_Scope (New_Id, New_Subp);
14790 -- Create a reference to it
14792 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14795 Set_Etype (New_Id, Id_Type);
14799 -- In Ada2012, a formal may have an incomplete type but the type
14800 -- derivation that inherits the primitive follows the full view.
14802 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14804 (Ekind (Id_Type) = E_Record_Type_With_Private
14805 and then Present (Full_View (Id_Type))
14807 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14809 (Ada_Version >= Ada_2012
14810 and then Ekind (Id_Type) = E_Incomplete_Type
14811 and then Full_View (Id_Type) = Parent_Type)
14813 -- Constraint checks on formals are generated during expansion,
14814 -- based on the signature of the original subprogram. The bounds
14815 -- of the derived type are not relevant, and thus we can use
14816 -- the base type for the formals. However, the return type may be
14817 -- used in a context that requires that the proper static bounds
14818 -- be used (a case statement, for example) and for those cases
14819 -- we must use the derived type (first subtype), not its base.
14821 -- If the derived_type_definition has no constraints, we know that
14822 -- the derived type has the same constraints as the first subtype
14823 -- of the parent, and we can also use it rather than its base,
14824 -- which can lead to more efficient code.
14826 if Etype (Id) = Parent_Type then
14827 if Is_Scalar_Type (Parent_Type)
14829 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14831 Set_Etype (New_Id, Derived_Type);
14833 elsif Nkind (Par) = N_Full_Type_Declaration
14835 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14838 (Subtype_Indication (Type_Definition (Par)))
14840 Set_Etype (New_Id, Derived_Type);
14843 Set_Etype (New_Id, Base_Type (Derived_Type));
14847 Set_Etype (New_Id, Base_Type (Derived_Type));
14851 Set_Etype (New_Id, Etype (Id));
14855 ----------------------
14856 -- Set_Derived_Name --
14857 ----------------------
14859 procedure Set_Derived_Name is
14860 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14862 if Nm = TSS_Null then
14863 Set_Chars (New_Subp, Chars (Parent_Subp));
14865 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14867 end Set_Derived_Name;
14869 -- Start of processing for Derive_Subprogram
14872 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14873 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14875 -- Check whether the inherited subprogram is a private operation that
14876 -- should be inherited but not yet made visible. Such subprograms can
14877 -- become visible at a later point (e.g., the private part of a public
14878 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14879 -- following predicate is true, then this is not such a private
14880 -- operation and the subprogram simply inherits the name of the parent
14881 -- subprogram. Note the special check for the names of controlled
14882 -- operations, which are currently exempted from being inherited with
14883 -- a hidden name because they must be findable for generation of
14884 -- implicit run-time calls.
14886 if not Is_Hidden (Parent_Subp)
14887 or else Is_Internal (Parent_Subp)
14888 or else Is_Private_Overriding
14889 or else Is_Internal_Name (Chars (Parent_Subp))
14890 or else (Is_Controlled (Parent_Type)
14891 and then Nam_In (Chars (Parent_Subp), Name_Adjust,
14897 -- An inherited dispatching equality will be overridden by an internally
14898 -- generated one, or by an explicit one, so preserve its name and thus
14899 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14900 -- private operation it may become invisible if the full view has
14901 -- progenitors, and the dispatch table will be malformed.
14902 -- We check that the type is limited to handle the anomalous declaration
14903 -- of Limited_Controlled, which is derived from a non-limited type, and
14904 -- which is handled specially elsewhere as well.
14906 elsif Chars (Parent_Subp) = Name_Op_Eq
14907 and then Is_Dispatching_Operation (Parent_Subp)
14908 and then Etype (Parent_Subp) = Standard_Boolean
14909 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14911 Etype (First_Formal (Parent_Subp)) =
14912 Etype (Next_Formal (First_Formal (Parent_Subp)))
14916 -- If parent is hidden, this can be a regular derivation if the
14917 -- parent is immediately visible in a non-instantiating context,
14918 -- or if we are in the private part of an instance. This test
14919 -- should still be refined ???
14921 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14922 -- operation as a non-visible operation in cases where the parent
14923 -- subprogram might not be visible now, but was visible within the
14924 -- original generic, so it would be wrong to make the inherited
14925 -- subprogram non-visible now. (Not clear if this test is fully
14926 -- correct; are there any cases where we should declare the inherited
14927 -- operation as not visible to avoid it being overridden, e.g., when
14928 -- the parent type is a generic actual with private primitives ???)
14930 -- (they should be treated the same as other private inherited
14931 -- subprograms, but it's not clear how to do this cleanly). ???
14933 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14934 and then Is_Immediately_Visible (Parent_Subp)
14935 and then not In_Instance)
14936 or else In_Instance_Not_Visible
14940 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14941 -- overrides an interface primitive because interface primitives
14942 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14944 elsif Ada_Version >= Ada_2005
14945 and then Is_Dispatching_Operation (Parent_Subp)
14946 and then Covers_Some_Interface (Parent_Subp)
14950 -- Otherwise, the type is inheriting a private operation, so enter it
14951 -- with a special name so it can't be overridden.
14954 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14957 Set_Parent (New_Subp, Parent (Derived_Type));
14959 if Present (Actual_Subp) then
14960 Replace_Type (Actual_Subp, New_Subp);
14962 Replace_Type (Parent_Subp, New_Subp);
14965 Conditional_Delay (New_Subp, Parent_Subp);
14967 -- If we are creating a renaming for a primitive operation of an
14968 -- actual of a generic derived type, we must examine the signature
14969 -- of the actual primitive, not that of the generic formal, which for
14970 -- example may be an interface. However the name and initial value
14971 -- of the inherited operation are those of the formal primitive.
14973 Formal := First_Formal (Parent_Subp);
14975 if Present (Actual_Subp) then
14976 Formal_Of_Actual := First_Formal (Actual_Subp);
14978 Formal_Of_Actual := Empty;
14981 while Present (Formal) loop
14982 New_Formal := New_Copy (Formal);
14984 -- Normally we do not go copying parents, but in the case of
14985 -- formals, we need to link up to the declaration (which is the
14986 -- parameter specification), and it is fine to link up to the
14987 -- original formal's parameter specification in this case.
14989 Set_Parent (New_Formal, Parent (Formal));
14990 Append_Entity (New_Formal, New_Subp);
14992 if Present (Formal_Of_Actual) then
14993 Replace_Type (Formal_Of_Actual, New_Formal);
14994 Next_Formal (Formal_Of_Actual);
14996 Replace_Type (Formal, New_Formal);
14999 Next_Formal (Formal);
15002 -- If this derivation corresponds to a tagged generic actual, then
15003 -- primitive operations rename those of the actual. Otherwise the
15004 -- primitive operations rename those of the parent type, If the parent
15005 -- renames an intrinsic operator, so does the new subprogram. We except
15006 -- concatenation, which is always properly typed, and does not get
15007 -- expanded as other intrinsic operations.
15009 if No (Actual_Subp) then
15010 if Is_Intrinsic_Subprogram (Parent_Subp) then
15011 Set_Is_Intrinsic_Subprogram (New_Subp);
15013 if Present (Alias (Parent_Subp))
15014 and then Chars (Parent_Subp) /= Name_Op_Concat
15016 Set_Alias (New_Subp, Alias (Parent_Subp));
15018 Set_Alias (New_Subp, Parent_Subp);
15022 Set_Alias (New_Subp, Parent_Subp);
15026 Set_Alias (New_Subp, Actual_Subp);
15029 -- Derived subprograms of a tagged type must inherit the convention
15030 -- of the parent subprogram (a requirement of AI-117). Derived
15031 -- subprograms of untagged types simply get convention Ada by default.
15033 -- If the derived type is a tagged generic formal type with unknown
15034 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
15036 -- However, if the type is derived from a generic formal, the further
15037 -- inherited subprogram has the convention of the non-generic ancestor.
15038 -- Otherwise there would be no way to override the operation.
15039 -- (This is subject to forthcoming ARG discussions).
15041 if Is_Tagged_Type (Derived_Type) then
15042 if Is_Generic_Type (Derived_Type)
15043 and then Has_Unknown_Discriminants (Derived_Type)
15045 Set_Convention (New_Subp, Convention_Intrinsic);
15048 if Is_Generic_Type (Parent_Type)
15049 and then Has_Unknown_Discriminants (Parent_Type)
15051 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
15053 Set_Convention (New_Subp, Convention (Parent_Subp));
15058 -- Predefined controlled operations retain their name even if the parent
15059 -- is hidden (see above), but they are not primitive operations if the
15060 -- ancestor is not visible, for example if the parent is a private
15061 -- extension completed with a controlled extension. Note that a full
15062 -- type that is controlled can break privacy: the flag Is_Controlled is
15063 -- set on both views of the type.
15065 if Is_Controlled (Parent_Type)
15066 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
15069 and then Is_Hidden (Parent_Subp)
15070 and then not Is_Visibly_Controlled (Parent_Type)
15072 Set_Is_Hidden (New_Subp);
15075 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
15076 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
15078 if Ekind (Parent_Subp) = E_Procedure then
15079 Set_Is_Valued_Procedure
15080 (New_Subp, Is_Valued_Procedure (Parent_Subp));
15082 Set_Has_Controlling_Result
15083 (New_Subp, Has_Controlling_Result (Parent_Subp));
15086 -- No_Return must be inherited properly. If this is overridden in the
15087 -- case of a dispatching operation, then a check is made in Sem_Disp
15088 -- that the overriding operation is also No_Return (no such check is
15089 -- required for the case of non-dispatching operation.
15091 Set_No_Return (New_Subp, No_Return (Parent_Subp));
15093 -- A derived function with a controlling result is abstract. If the
15094 -- Derived_Type is a nonabstract formal generic derived type, then
15095 -- inherited operations are not abstract: the required check is done at
15096 -- instantiation time. If the derivation is for a generic actual, the
15097 -- function is not abstract unless the actual is.
15099 if Is_Generic_Type (Derived_Type)
15100 and then not Is_Abstract_Type (Derived_Type)
15104 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
15105 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
15107 -- A subprogram subject to pragma Extensions_Visible with value False
15108 -- requires overriding if the subprogram has at least one controlling
15109 -- OUT parameter (SPARK RM 6.1.7(6)).
15111 elsif Ada_Version >= Ada_2005
15112 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15113 or else (Is_Tagged_Type (Derived_Type)
15114 and then Etype (New_Subp) = Derived_Type
15115 and then not Is_Null_Extension (Derived_Type))
15116 or else (Is_Tagged_Type (Derived_Type)
15117 and then Ekind (Etype (New_Subp)) =
15118 E_Anonymous_Access_Type
15119 and then Designated_Type (Etype (New_Subp)) =
15121 and then not Is_Null_Extension (Derived_Type))
15122 or else (Comes_From_Source (Alias (New_Subp))
15123 and then Is_EVF_Procedure (Alias (New_Subp))))
15124 and then No (Actual_Subp)
15126 if not Is_Tagged_Type (Derived_Type)
15127 or else Is_Abstract_Type (Derived_Type)
15128 or else Is_Abstract_Subprogram (Alias (New_Subp))
15130 Set_Is_Abstract_Subprogram (New_Subp);
15132 Set_Requires_Overriding (New_Subp);
15135 elsif Ada_Version < Ada_2005
15136 and then (Is_Abstract_Subprogram (Alias (New_Subp))
15137 or else (Is_Tagged_Type (Derived_Type)
15138 and then Etype (New_Subp) = Derived_Type
15139 and then No (Actual_Subp)))
15141 Set_Is_Abstract_Subprogram (New_Subp);
15143 -- AI05-0097 : an inherited operation that dispatches on result is
15144 -- abstract if the derived type is abstract, even if the parent type
15145 -- is concrete and the derived type is a null extension.
15147 elsif Has_Controlling_Result (Alias (New_Subp))
15148 and then Is_Abstract_Type (Etype (New_Subp))
15150 Set_Is_Abstract_Subprogram (New_Subp);
15152 -- Finally, if the parent type is abstract we must verify that all
15153 -- inherited operations are either non-abstract or overridden, or that
15154 -- the derived type itself is abstract (this check is performed at the
15155 -- end of a package declaration, in Check_Abstract_Overriding). A
15156 -- private overriding in the parent type will not be visible in the
15157 -- derivation if we are not in an inner package or in a child unit of
15158 -- the parent type, in which case the abstractness of the inherited
15159 -- operation is carried to the new subprogram.
15161 elsif Is_Abstract_Type (Parent_Type)
15162 and then not In_Open_Scopes (Scope (Parent_Type))
15163 and then Is_Private_Overriding
15164 and then Is_Abstract_Subprogram (Visible_Subp)
15166 if No (Actual_Subp) then
15167 Set_Alias (New_Subp, Visible_Subp);
15168 Set_Is_Abstract_Subprogram (New_Subp, True);
15171 -- If this is a derivation for an instance of a formal derived
15172 -- type, abstractness comes from the primitive operation of the
15173 -- actual, not from the operation inherited from the ancestor.
15175 Set_Is_Abstract_Subprogram
15176 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
15180 New_Overloaded_Entity (New_Subp, Derived_Type);
15182 -- Check for case of a derived subprogram for the instantiation of a
15183 -- formal derived tagged type, if so mark the subprogram as dispatching
15184 -- and inherit the dispatching attributes of the actual subprogram. The
15185 -- derived subprogram is effectively renaming of the actual subprogram,
15186 -- so it needs to have the same attributes as the actual.
15188 if Present (Actual_Subp)
15189 and then Is_Dispatching_Operation (Actual_Subp)
15191 Set_Is_Dispatching_Operation (New_Subp);
15193 if Present (DTC_Entity (Actual_Subp)) then
15194 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
15195 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
15199 -- Indicate that a derived subprogram does not require a body and that
15200 -- it does not require processing of default expressions.
15202 Set_Has_Completion (New_Subp);
15203 Set_Default_Expressions_Processed (New_Subp);
15205 if Ekind (New_Subp) = E_Function then
15206 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
15208 end Derive_Subprogram;
15210 ------------------------
15211 -- Derive_Subprograms --
15212 ------------------------
15214 procedure Derive_Subprograms
15215 (Parent_Type : Entity_Id;
15216 Derived_Type : Entity_Id;
15217 Generic_Actual : Entity_Id := Empty)
15219 Op_List : constant Elist_Id :=
15220 Collect_Primitive_Operations (Parent_Type);
15222 function Check_Derived_Type return Boolean;
15223 -- Check that all the entities derived from Parent_Type are found in
15224 -- the list of primitives of Derived_Type exactly in the same order.
15226 procedure Derive_Interface_Subprogram
15227 (New_Subp : out Entity_Id;
15229 Actual_Subp : Entity_Id);
15230 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
15231 -- (which is an interface primitive). If Generic_Actual is present then
15232 -- Actual_Subp is the actual subprogram corresponding with the generic
15233 -- subprogram Subp.
15235 ------------------------
15236 -- Check_Derived_Type --
15237 ------------------------
15239 function Check_Derived_Type return Boolean is
15243 New_Subp : Entity_Id;
15248 -- Traverse list of entities in the current scope searching for
15249 -- an incomplete type whose full-view is derived type.
15251 E := First_Entity (Scope (Derived_Type));
15252 while Present (E) and then E /= Derived_Type loop
15253 if Ekind (E) = E_Incomplete_Type
15254 and then Present (Full_View (E))
15255 and then Full_View (E) = Derived_Type
15257 -- Disable this test if Derived_Type completes an incomplete
15258 -- type because in such case more primitives can be added
15259 -- later to the list of primitives of Derived_Type by routine
15260 -- Process_Incomplete_Dependents
15265 E := Next_Entity (E);
15268 List := Collect_Primitive_Operations (Derived_Type);
15269 Elmt := First_Elmt (List);
15271 Op_Elmt := First_Elmt (Op_List);
15272 while Present (Op_Elmt) loop
15273 Subp := Node (Op_Elmt);
15274 New_Subp := Node (Elmt);
15276 -- At this early stage Derived_Type has no entities with attribute
15277 -- Interface_Alias. In addition, such primitives are always
15278 -- located at the end of the list of primitives of Parent_Type.
15279 -- Therefore, if found we can safely stop processing pending
15282 exit when Present (Interface_Alias (Subp));
15284 -- Handle hidden entities
15286 if not Is_Predefined_Dispatching_Operation (Subp)
15287 and then Is_Hidden (Subp)
15289 if Present (New_Subp)
15290 and then Primitive_Names_Match (Subp, New_Subp)
15296 if not Present (New_Subp)
15297 or else Ekind (Subp) /= Ekind (New_Subp)
15298 or else not Primitive_Names_Match (Subp, New_Subp)
15306 Next_Elmt (Op_Elmt);
15310 end Check_Derived_Type;
15312 ---------------------------------
15313 -- Derive_Interface_Subprogram --
15314 ---------------------------------
15316 procedure Derive_Interface_Subprogram
15317 (New_Subp : out Entity_Id;
15319 Actual_Subp : Entity_Id)
15321 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15322 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15325 pragma Assert (Is_Interface (Iface_Type));
15328 (New_Subp => New_Subp,
15329 Parent_Subp => Iface_Subp,
15330 Derived_Type => Derived_Type,
15331 Parent_Type => Iface_Type,
15332 Actual_Subp => Actual_Subp);
15334 -- Given that this new interface entity corresponds with a primitive
15335 -- of the parent that was not overridden we must leave it associated
15336 -- with its parent primitive to ensure that it will share the same
15337 -- dispatch table slot when overridden. We must set the Alias to Subp
15338 -- (instead of Iface_Subp), and we must fix Is_Abstract_Subprogram
15339 -- (in case we inherited Subp from Iface_Type via a nonabstract
15340 -- generic formal type).
15342 if No (Actual_Subp) then
15343 Set_Alias (New_Subp, Subp);
15346 T : Entity_Id := Find_Dispatching_Type (Subp);
15348 while Etype (T) /= T loop
15349 if Is_Generic_Type (T) and then not Is_Abstract_Type (T) then
15350 Set_Is_Abstract_Subprogram (New_Subp, False);
15358 -- For instantiations this is not needed since the previous call to
15359 -- Derive_Subprogram leaves the entity well decorated.
15362 pragma Assert (Alias (New_Subp) = Actual_Subp);
15365 end Derive_Interface_Subprogram;
15369 Alias_Subp : Entity_Id;
15370 Act_List : Elist_Id;
15371 Act_Elmt : Elmt_Id;
15372 Act_Subp : Entity_Id := Empty;
15374 Need_Search : Boolean := False;
15375 New_Subp : Entity_Id := Empty;
15376 Parent_Base : Entity_Id;
15379 -- Start of processing for Derive_Subprograms
15382 if Ekind (Parent_Type) = E_Record_Type_With_Private
15383 and then Has_Discriminants (Parent_Type)
15384 and then Present (Full_View (Parent_Type))
15386 Parent_Base := Full_View (Parent_Type);
15388 Parent_Base := Parent_Type;
15391 if Present (Generic_Actual) then
15392 Act_List := Collect_Primitive_Operations (Generic_Actual);
15393 Act_Elmt := First_Elmt (Act_List);
15395 Act_List := No_Elist;
15396 Act_Elmt := No_Elmt;
15399 -- Derive primitives inherited from the parent. Note that if the generic
15400 -- actual is present, this is not really a type derivation, it is a
15401 -- completion within an instance.
15403 -- Case 1: Derived_Type does not implement interfaces
15405 if not Is_Tagged_Type (Derived_Type)
15406 or else (not Has_Interfaces (Derived_Type)
15407 and then not (Present (Generic_Actual)
15408 and then Has_Interfaces (Generic_Actual)))
15410 Elmt := First_Elmt (Op_List);
15411 while Present (Elmt) loop
15412 Subp := Node (Elmt);
15414 -- Literals are derived earlier in the process of building the
15415 -- derived type, and are skipped here.
15417 if Ekind (Subp) = E_Enumeration_Literal then
15420 -- The actual is a direct descendant and the common primitive
15421 -- operations appear in the same order.
15423 -- If the generic parent type is present, the derived type is an
15424 -- instance of a formal derived type, and within the instance its
15425 -- operations are those of the actual. We derive from the formal
15426 -- type but make the inherited operations aliases of the
15427 -- corresponding operations of the actual.
15430 pragma Assert (No (Node (Act_Elmt))
15431 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15434 (Subp, Node (Act_Elmt),
15435 Skip_Controlling_Formals => True)));
15438 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15440 if Present (Act_Elmt) then
15441 Next_Elmt (Act_Elmt);
15448 -- Case 2: Derived_Type implements interfaces
15451 -- If the parent type has no predefined primitives we remove
15452 -- predefined primitives from the list of primitives of generic
15453 -- actual to simplify the complexity of this algorithm.
15455 if Present (Generic_Actual) then
15457 Has_Predefined_Primitives : Boolean := False;
15460 -- Check if the parent type has predefined primitives
15462 Elmt := First_Elmt (Op_List);
15463 while Present (Elmt) loop
15464 Subp := Node (Elmt);
15466 if Is_Predefined_Dispatching_Operation (Subp)
15467 and then not Comes_From_Source (Ultimate_Alias (Subp))
15469 Has_Predefined_Primitives := True;
15476 -- Remove predefined primitives of Generic_Actual. We must use
15477 -- an auxiliary list because in case of tagged types the value
15478 -- returned by Collect_Primitive_Operations is the value stored
15479 -- in its Primitive_Operations attribute (and we don't want to
15480 -- modify its current contents).
15482 if not Has_Predefined_Primitives then
15484 Aux_List : constant Elist_Id := New_Elmt_List;
15487 Elmt := First_Elmt (Act_List);
15488 while Present (Elmt) loop
15489 Subp := Node (Elmt);
15491 if not Is_Predefined_Dispatching_Operation (Subp)
15492 or else Comes_From_Source (Subp)
15494 Append_Elmt (Subp, Aux_List);
15500 Act_List := Aux_List;
15504 Act_Elmt := First_Elmt (Act_List);
15505 Act_Subp := Node (Act_Elmt);
15509 -- Stage 1: If the generic actual is not present we derive the
15510 -- primitives inherited from the parent type. If the generic parent
15511 -- type is present, the derived type is an instance of a formal
15512 -- derived type, and within the instance its operations are those of
15513 -- the actual. We derive from the formal type but make the inherited
15514 -- operations aliases of the corresponding operations of the actual.
15516 Elmt := First_Elmt (Op_List);
15517 while Present (Elmt) loop
15518 Subp := Node (Elmt);
15519 Alias_Subp := Ultimate_Alias (Subp);
15521 -- Do not derive internal entities of the parent that link
15522 -- interface primitives with their covering primitive. These
15523 -- entities will be added to this type when frozen.
15525 if Present (Interface_Alias (Subp)) then
15529 -- If the generic actual is present find the corresponding
15530 -- operation in the generic actual. If the parent type is a
15531 -- direct ancestor of the derived type then, even if it is an
15532 -- interface, the operations are inherited from the primary
15533 -- dispatch table and are in the proper order. If we detect here
15534 -- that primitives are not in the same order we traverse the list
15535 -- of primitive operations of the actual to find the one that
15536 -- implements the interface primitive.
15540 (Present (Generic_Actual)
15541 and then Present (Act_Subp)
15543 (Primitive_Names_Match (Subp, Act_Subp)
15545 Type_Conformant (Subp, Act_Subp,
15546 Skip_Controlling_Formals => True)))
15548 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15549 Use_Full_View => True));
15551 -- Remember that we need searching for all pending primitives
15553 Need_Search := True;
15555 -- Handle entities associated with interface primitives
15557 if Present (Alias_Subp)
15558 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15559 and then not Is_Predefined_Dispatching_Operation (Subp)
15561 -- Search for the primitive in the homonym chain
15564 Find_Primitive_Covering_Interface
15565 (Tagged_Type => Generic_Actual,
15566 Iface_Prim => Alias_Subp);
15568 -- Previous search may not locate primitives covering
15569 -- interfaces defined in generics units or instantiations.
15570 -- (it fails if the covering primitive has formals whose
15571 -- type is also defined in generics or instantiations).
15572 -- In such case we search in the list of primitives of the
15573 -- generic actual for the internal entity that links the
15574 -- interface primitive and the covering primitive.
15577 and then Is_Generic_Type (Parent_Type)
15579 -- This code has been designed to handle only generic
15580 -- formals that implement interfaces that are defined
15581 -- in a generic unit or instantiation. If this code is
15582 -- needed for other cases we must review it because
15583 -- (given that it relies on Original_Location to locate
15584 -- the primitive of Generic_Actual that covers the
15585 -- interface) it could leave linked through attribute
15586 -- Alias entities of unrelated instantiations).
15590 (Scope (Find_Dispatching_Type (Alias_Subp)))
15592 Instantiation_Depth
15593 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15596 Iface_Prim_Loc : constant Source_Ptr :=
15597 Original_Location (Sloc (Alias_Subp));
15604 First_Elmt (Primitive_Operations (Generic_Actual));
15606 Search : while Present (Elmt) loop
15607 Prim := Node (Elmt);
15609 if Present (Interface_Alias (Prim))
15610 and then Original_Location
15611 (Sloc (Interface_Alias (Prim))) =
15614 Act_Subp := Alias (Prim);
15623 pragma Assert (Present (Act_Subp)
15624 or else Is_Abstract_Type (Generic_Actual)
15625 or else Serious_Errors_Detected > 0);
15627 -- Handle predefined primitives plus the rest of user-defined
15631 Act_Elmt := First_Elmt (Act_List);
15632 while Present (Act_Elmt) loop
15633 Act_Subp := Node (Act_Elmt);
15635 exit when Primitive_Names_Match (Subp, Act_Subp)
15636 and then Type_Conformant
15638 Skip_Controlling_Formals => True)
15639 and then No (Interface_Alias (Act_Subp));
15641 Next_Elmt (Act_Elmt);
15644 if No (Act_Elmt) then
15650 -- Case 1: If the parent is a limited interface then it has the
15651 -- predefined primitives of synchronized interfaces. However, the
15652 -- actual type may be a non-limited type and hence it does not
15653 -- have such primitives.
15655 if Present (Generic_Actual)
15656 and then not Present (Act_Subp)
15657 and then Is_Limited_Interface (Parent_Base)
15658 and then Is_Predefined_Interface_Primitive (Subp)
15662 -- Case 2: Inherit entities associated with interfaces that were
15663 -- not covered by the parent type. We exclude here null interface
15664 -- primitives because they do not need special management.
15666 -- We also exclude interface operations that are renamings. If the
15667 -- subprogram is an explicit renaming of an interface primitive,
15668 -- it is a regular primitive operation, and the presence of its
15669 -- alias is not relevant: it has to be derived like any other
15672 elsif Present (Alias (Subp))
15673 and then Nkind (Unit_Declaration_Node (Subp)) /=
15674 N_Subprogram_Renaming_Declaration
15675 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15677 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15678 and then Null_Present (Parent (Alias_Subp)))
15680 -- If this is an abstract private type then we transfer the
15681 -- derivation of the interface primitive from the partial view
15682 -- to the full view. This is safe because all the interfaces
15683 -- must be visible in the partial view. Done to avoid adding
15684 -- a new interface derivation to the private part of the
15685 -- enclosing package; otherwise this new derivation would be
15686 -- decorated as hidden when the analysis of the enclosing
15687 -- package completes.
15689 if Is_Abstract_Type (Derived_Type)
15690 and then In_Private_Part (Current_Scope)
15691 and then Has_Private_Declaration (Derived_Type)
15694 Partial_View : Entity_Id;
15699 Partial_View := First_Entity (Current_Scope);
15701 exit when No (Partial_View)
15702 or else (Has_Private_Declaration (Partial_View)
15704 Full_View (Partial_View) = Derived_Type);
15706 Next_Entity (Partial_View);
15709 -- If the partial view was not found then the source code
15710 -- has errors and the derivation is not needed.
15712 if Present (Partial_View) then
15714 First_Elmt (Primitive_Operations (Partial_View));
15715 while Present (Elmt) loop
15716 Ent := Node (Elmt);
15718 if Present (Alias (Ent))
15719 and then Ultimate_Alias (Ent) = Alias (Subp)
15722 (Ent, Primitive_Operations (Derived_Type));
15729 -- If the interface primitive was not found in the
15730 -- partial view then this interface primitive was
15731 -- overridden. We add a derivation to activate in
15732 -- Derive_Progenitor_Subprograms the machinery to
15736 Derive_Interface_Subprogram
15737 (New_Subp => New_Subp,
15739 Actual_Subp => Act_Subp);
15744 Derive_Interface_Subprogram
15745 (New_Subp => New_Subp,
15747 Actual_Subp => Act_Subp);
15750 -- Case 3: Common derivation
15754 (New_Subp => New_Subp,
15755 Parent_Subp => Subp,
15756 Derived_Type => Derived_Type,
15757 Parent_Type => Parent_Base,
15758 Actual_Subp => Act_Subp);
15761 -- No need to update Act_Elm if we must search for the
15762 -- corresponding operation in the generic actual
15765 and then Present (Act_Elmt)
15767 Next_Elmt (Act_Elmt);
15768 Act_Subp := Node (Act_Elmt);
15775 -- Inherit additional operations from progenitors. If the derived
15776 -- type is a generic actual, there are not new primitive operations
15777 -- for the type because it has those of the actual, and therefore
15778 -- nothing needs to be done. The renamings generated above are not
15779 -- primitive operations, and their purpose is simply to make the
15780 -- proper operations visible within an instantiation.
15782 if No (Generic_Actual) then
15783 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15787 -- Final check: Direct descendants must have their primitives in the
15788 -- same order. We exclude from this test untagged types and instances
15789 -- of formal derived types. We skip this test if we have already
15790 -- reported serious errors in the sources.
15792 pragma Assert (not Is_Tagged_Type (Derived_Type)
15793 or else Present (Generic_Actual)
15794 or else Serious_Errors_Detected > 0
15795 or else Check_Derived_Type);
15796 end Derive_Subprograms;
15798 --------------------------------
15799 -- Derived_Standard_Character --
15800 --------------------------------
15802 procedure Derived_Standard_Character
15804 Parent_Type : Entity_Id;
15805 Derived_Type : Entity_Id)
15807 Loc : constant Source_Ptr := Sloc (N);
15808 Def : constant Node_Id := Type_Definition (N);
15809 Indic : constant Node_Id := Subtype_Indication (Def);
15810 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15811 Implicit_Base : constant Entity_Id :=
15813 (E_Enumeration_Type, N, Derived_Type, 'B');
15819 Discard_Node (Process_Subtype (Indic, N));
15821 Set_Etype (Implicit_Base, Parent_Base);
15822 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15823 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15825 Set_Is_Character_Type (Implicit_Base, True);
15826 Set_Has_Delayed_Freeze (Implicit_Base);
15828 -- The bounds of the implicit base are the bounds of the parent base.
15829 -- Note that their type is the parent base.
15831 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15832 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15834 Set_Scalar_Range (Implicit_Base,
15837 High_Bound => Hi));
15839 Conditional_Delay (Derived_Type, Parent_Type);
15841 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15842 Set_Etype (Derived_Type, Implicit_Base);
15843 Set_Size_Info (Derived_Type, Parent_Type);
15845 if Unknown_RM_Size (Derived_Type) then
15846 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15849 Set_Is_Character_Type (Derived_Type, True);
15851 if Nkind (Indic) /= N_Subtype_Indication then
15853 -- If no explicit constraint, the bounds are those
15854 -- of the parent type.
15856 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15857 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15858 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15861 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15863 -- Because the implicit base is used in the conversion of the bounds, we
15864 -- have to freeze it now. This is similar to what is done for numeric
15865 -- types, and it equally suspicious, but otherwise a non-static bound
15866 -- will have a reference to an unfrozen type, which is rejected by Gigi
15867 -- (???). This requires specific care for definition of stream
15868 -- attributes. For details, see comments at the end of
15869 -- Build_Derived_Numeric_Type.
15871 Freeze_Before (N, Implicit_Base);
15872 end Derived_Standard_Character;
15874 ------------------------------
15875 -- Derived_Type_Declaration --
15876 ------------------------------
15878 procedure Derived_Type_Declaration
15881 Is_Completion : Boolean)
15883 Parent_Type : Entity_Id;
15885 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15886 -- Check whether the parent type is a generic formal, or derives
15887 -- directly or indirectly from one.
15889 ------------------------
15890 -- Comes_From_Generic --
15891 ------------------------
15893 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15895 if Is_Generic_Type (Typ) then
15898 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15901 elsif Is_Private_Type (Typ)
15902 and then Present (Full_View (Typ))
15903 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15907 elsif Is_Generic_Actual_Type (Typ) then
15913 end Comes_From_Generic;
15917 Def : constant Node_Id := Type_Definition (N);
15918 Iface_Def : Node_Id;
15919 Indic : constant Node_Id := Subtype_Indication (Def);
15920 Extension : constant Node_Id := Record_Extension_Part (Def);
15921 Parent_Node : Node_Id;
15924 -- Start of processing for Derived_Type_Declaration
15927 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15929 -- Ada 2005 (AI-251): In case of interface derivation check that the
15930 -- parent is also an interface.
15932 if Interface_Present (Def) then
15933 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15935 if not Is_Interface (Parent_Type) then
15936 Diagnose_Interface (Indic, Parent_Type);
15939 Parent_Node := Parent (Base_Type (Parent_Type));
15940 Iface_Def := Type_Definition (Parent_Node);
15942 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15943 -- other limited interfaces.
15945 if Limited_Present (Def) then
15946 if Limited_Present (Iface_Def) then
15949 elsif Protected_Present (Iface_Def) then
15951 ("descendant of & must be declared as a protected "
15952 & "interface", N, Parent_Type);
15954 elsif Synchronized_Present (Iface_Def) then
15956 ("descendant of & must be declared as a synchronized "
15957 & "interface", N, Parent_Type);
15959 elsif Task_Present (Iface_Def) then
15961 ("descendant of & must be declared as a task interface",
15966 ("(Ada 2005) limited interface cannot inherit from "
15967 & "non-limited interface", Indic);
15970 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15971 -- from non-limited or limited interfaces.
15973 elsif not Protected_Present (Def)
15974 and then not Synchronized_Present (Def)
15975 and then not Task_Present (Def)
15977 if Limited_Present (Iface_Def) then
15980 elsif Protected_Present (Iface_Def) then
15982 ("descendant of & must be declared as a protected "
15983 & "interface", N, Parent_Type);
15985 elsif Synchronized_Present (Iface_Def) then
15987 ("descendant of & must be declared as a synchronized "
15988 & "interface", N, Parent_Type);
15990 elsif Task_Present (Iface_Def) then
15992 ("descendant of & must be declared as a task interface",
16001 if Is_Tagged_Type (Parent_Type)
16002 and then Is_Concurrent_Type (Parent_Type)
16003 and then not Is_Interface (Parent_Type)
16006 ("parent type of a record extension cannot be a synchronized "
16007 & "tagged type (RM 3.9.1 (3/1))", N);
16008 Set_Etype (T, Any_Type);
16012 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
16015 if Is_Tagged_Type (Parent_Type)
16016 and then Is_Non_Empty_List (Interface_List (Def))
16023 Intf := First (Interface_List (Def));
16024 while Present (Intf) loop
16025 T := Find_Type_Of_Subtype_Indic (Intf);
16027 if not Is_Interface (T) then
16028 Diagnose_Interface (Intf, T);
16030 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
16031 -- a limited type from having a nonlimited progenitor.
16033 elsif (Limited_Present (Def)
16034 or else (not Is_Interface (Parent_Type)
16035 and then Is_Limited_Type (Parent_Type)))
16036 and then not Is_Limited_Interface (T)
16039 ("progenitor interface& of limited type must be limited",
16048 if Parent_Type = Any_Type
16049 or else Etype (Parent_Type) = Any_Type
16050 or else (Is_Class_Wide_Type (Parent_Type)
16051 and then Etype (Parent_Type) = T)
16053 -- If Parent_Type is undefined or illegal, make new type into a
16054 -- subtype of Any_Type, and set a few attributes to prevent cascaded
16055 -- errors. If this is a self-definition, emit error now.
16057 if T = Parent_Type or else T = Etype (Parent_Type) then
16058 Error_Msg_N ("type cannot be used in its own definition", Indic);
16061 Set_Ekind (T, Ekind (Parent_Type));
16062 Set_Etype (T, Any_Type);
16063 Set_Scalar_Range (T, Scalar_Range (Any_Type));
16065 if Is_Tagged_Type (T)
16066 and then Is_Record_Type (T)
16068 Set_Direct_Primitive_Operations (T, New_Elmt_List);
16074 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
16075 -- an interface is special because the list of interfaces in the full
16076 -- view can be given in any order. For example:
16078 -- type A is interface;
16079 -- type B is interface and A;
16080 -- type D is new B with private;
16082 -- type D is new A and B with null record; -- 1 --
16084 -- In this case we perform the following transformation of -1-:
16086 -- type D is new B and A with null record;
16088 -- If the parent of the full-view covers the parent of the partial-view
16089 -- we have two possible cases:
16091 -- 1) They have the same parent
16092 -- 2) The parent of the full-view implements some further interfaces
16094 -- In both cases we do not need to perform the transformation. In the
16095 -- first case the source program is correct and the transformation is
16096 -- not needed; in the second case the source program does not fulfill
16097 -- the no-hidden interfaces rule (AI-396) and the error will be reported
16100 -- This transformation not only simplifies the rest of the analysis of
16101 -- this type declaration but also simplifies the correct generation of
16102 -- the object layout to the expander.
16104 if In_Private_Part (Current_Scope)
16105 and then Is_Interface (Parent_Type)
16109 Partial_View : Entity_Id;
16110 Partial_View_Parent : Entity_Id;
16111 New_Iface : Node_Id;
16114 -- Look for the associated private type declaration
16116 Partial_View := First_Entity (Current_Scope);
16118 exit when No (Partial_View)
16119 or else (Has_Private_Declaration (Partial_View)
16120 and then Full_View (Partial_View) = T);
16122 Next_Entity (Partial_View);
16125 -- If the partial view was not found then the source code has
16126 -- errors and the transformation is not needed.
16128 if Present (Partial_View) then
16129 Partial_View_Parent := Etype (Partial_View);
16131 -- If the parent of the full-view covers the parent of the
16132 -- partial-view we have nothing else to do.
16134 if Interface_Present_In_Ancestor
16135 (Parent_Type, Partial_View_Parent)
16139 -- Traverse the list of interfaces of the full-view to look
16140 -- for the parent of the partial-view and perform the tree
16144 Iface := First (Interface_List (Def));
16145 while Present (Iface) loop
16146 if Etype (Iface) = Etype (Partial_View) then
16147 Rewrite (Subtype_Indication (Def),
16148 New_Copy (Subtype_Indication
16149 (Parent (Partial_View))));
16152 Make_Identifier (Sloc (N), Chars (Parent_Type));
16153 Append (New_Iface, Interface_List (Def));
16155 -- Analyze the transformed code
16157 Derived_Type_Declaration (T, N, Is_Completion);
16168 -- Only composite types other than array types are allowed to have
16171 if Present (Discriminant_Specifications (N)) then
16172 if (Is_Elementary_Type (Parent_Type)
16174 Is_Array_Type (Parent_Type))
16175 and then not Error_Posted (N)
16178 ("elementary or array type cannot have discriminants",
16179 Defining_Identifier (First (Discriminant_Specifications (N))));
16180 Set_Has_Discriminants (T, False);
16182 -- The type is allowed to have discriminants
16185 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
16189 -- In Ada 83, a derived type defined in a package specification cannot
16190 -- be used for further derivation until the end of its visible part.
16191 -- Note that derivation in the private part of the package is allowed.
16193 if Ada_Version = Ada_83
16194 and then Is_Derived_Type (Parent_Type)
16195 and then In_Visible_Part (Scope (Parent_Type))
16197 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
16199 ("(Ada 83): premature use of type for derivation", Indic);
16203 -- Check for early use of incomplete or private type
16205 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
16206 Error_Msg_N ("premature derivation of incomplete type", Indic);
16209 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
16210 and then not Comes_From_Generic (Parent_Type))
16211 or else Has_Private_Component (Parent_Type)
16213 -- The ancestor type of a formal type can be incomplete, in which
16214 -- case only the operations of the partial view are available in the
16215 -- generic. Subsequent checks may be required when the full view is
16216 -- analyzed to verify that a derivation from a tagged type has an
16219 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
16222 elsif No (Underlying_Type (Parent_Type))
16223 or else Has_Private_Component (Parent_Type)
16226 ("premature derivation of derived or private type", Indic);
16228 -- Flag the type itself as being in error, this prevents some
16229 -- nasty problems with subsequent uses of the malformed type.
16231 Set_Error_Posted (T);
16233 -- Check that within the immediate scope of an untagged partial
16234 -- view it's illegal to derive from the partial view if the
16235 -- full view is tagged. (7.3(7))
16237 -- We verify that the Parent_Type is a partial view by checking
16238 -- that it is not a Full_Type_Declaration (i.e. a private type or
16239 -- private extension declaration), to distinguish a partial view
16240 -- from a derivation from a private type which also appears as
16241 -- E_Private_Type. If the parent base type is not declared in an
16242 -- enclosing scope there is no need to check.
16244 elsif Present (Full_View (Parent_Type))
16245 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
16246 and then not Is_Tagged_Type (Parent_Type)
16247 and then Is_Tagged_Type (Full_View (Parent_Type))
16248 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
16251 ("premature derivation from type with tagged full view",
16256 -- Check that form of derivation is appropriate
16258 Taggd := Is_Tagged_Type (Parent_Type);
16260 -- Set the parent type to the class-wide type's specific type in this
16261 -- case to prevent cascading errors
16263 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
16264 Error_Msg_N ("parent type must not be a class-wide type", Indic);
16265 Set_Etype (T, Etype (Parent_Type));
16269 if Present (Extension) and then not Taggd then
16271 ("type derived from untagged type cannot have extension", Indic);
16273 elsif No (Extension) and then Taggd then
16275 -- If this declaration is within a private part (or body) of a
16276 -- generic instantiation then the derivation is allowed (the parent
16277 -- type can only appear tagged in this case if it's a generic actual
16278 -- type, since it would otherwise have been rejected in the analysis
16279 -- of the generic template).
16281 if not Is_Generic_Actual_Type (Parent_Type)
16282 or else In_Visible_Part (Scope (Parent_Type))
16284 if Is_Class_Wide_Type (Parent_Type) then
16286 ("parent type must not be a class-wide type", Indic);
16288 -- Use specific type to prevent cascaded errors.
16290 Parent_Type := Etype (Parent_Type);
16294 ("type derived from tagged type must have extension", Indic);
16299 -- AI-443: Synchronized formal derived types require a private
16300 -- extension. There is no point in checking the ancestor type or
16301 -- the progenitors since the construct is wrong to begin with.
16303 if Ada_Version >= Ada_2005
16304 and then Is_Generic_Type (T)
16305 and then Present (Original_Node (N))
16308 Decl : constant Node_Id := Original_Node (N);
16311 if Nkind (Decl) = N_Formal_Type_Declaration
16312 and then Nkind (Formal_Type_Definition (Decl)) =
16313 N_Formal_Derived_Type_Definition
16314 and then Synchronized_Present (Formal_Type_Definition (Decl))
16315 and then No (Extension)
16317 -- Avoid emitting a duplicate error message
16319 and then not Error_Posted (Indic)
16322 ("synchronized derived type must have extension", N);
16327 if Null_Exclusion_Present (Def)
16328 and then not Is_Access_Type (Parent_Type)
16330 Error_Msg_N ("null exclusion can only apply to an access type", N);
16333 -- Avoid deriving parent primitives of underlying record views
16335 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16336 Derive_Subps => not Is_Underlying_Record_View (T));
16338 -- AI-419: The parent type of an explicitly limited derived type must
16339 -- be a limited type or a limited interface.
16341 if Limited_Present (Def) then
16342 Set_Is_Limited_Record (T);
16344 if Is_Interface (T) then
16345 Set_Is_Limited_Interface (T);
16348 if not Is_Limited_Type (Parent_Type)
16350 (not Is_Interface (Parent_Type)
16351 or else not Is_Limited_Interface (Parent_Type))
16353 -- AI05-0096: a derivation in the private part of an instance is
16354 -- legal if the generic formal is untagged limited, and the actual
16357 if Is_Generic_Actual_Type (Parent_Type)
16358 and then In_Private_Part (Current_Scope)
16361 (Generic_Parent_Type (Parent (Parent_Type)))
16367 ("parent type& of limited type must be limited",
16373 -- In SPARK, there are no derived type definitions other than type
16374 -- extensions of tagged record types.
16376 if No (Extension) then
16377 Check_SPARK_05_Restriction
16378 ("derived type is not allowed", Original_Node (N));
16380 end Derived_Type_Declaration;
16382 ------------------------
16383 -- Diagnose_Interface --
16384 ------------------------
16386 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16388 if not Is_Interface (E) and then E /= Any_Type then
16389 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16391 end Diagnose_Interface;
16393 ----------------------------------
16394 -- Enumeration_Type_Declaration --
16395 ----------------------------------
16397 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16404 -- Create identifier node representing lower bound
16406 B_Node := New_Node (N_Identifier, Sloc (Def));
16407 L := First (Literals (Def));
16408 Set_Chars (B_Node, Chars (L));
16409 Set_Entity (B_Node, L);
16410 Set_Etype (B_Node, T);
16411 Set_Is_Static_Expression (B_Node, True);
16413 R_Node := New_Node (N_Range, Sloc (Def));
16414 Set_Low_Bound (R_Node, B_Node);
16416 Set_Ekind (T, E_Enumeration_Type);
16417 Set_First_Literal (T, L);
16419 Set_Is_Constrained (T);
16423 -- Loop through literals of enumeration type setting pos and rep values
16424 -- except that if the Ekind is already set, then it means the literal
16425 -- was already constructed (case of a derived type declaration and we
16426 -- should not disturb the Pos and Rep values.
16428 while Present (L) loop
16429 if Ekind (L) /= E_Enumeration_Literal then
16430 Set_Ekind (L, E_Enumeration_Literal);
16431 Set_Enumeration_Pos (L, Ev);
16432 Set_Enumeration_Rep (L, Ev);
16433 Set_Is_Known_Valid (L, True);
16437 New_Overloaded_Entity (L);
16438 Generate_Definition (L);
16439 Set_Convention (L, Convention_Intrinsic);
16441 -- Case of character literal
16443 if Nkind (L) = N_Defining_Character_Literal then
16444 Set_Is_Character_Type (T, True);
16446 -- Check violation of No_Wide_Characters
16448 if Restriction_Check_Required (No_Wide_Characters) then
16449 Get_Name_String (Chars (L));
16451 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16452 Check_Restriction (No_Wide_Characters, L);
16461 -- Now create a node representing upper bound
16463 B_Node := New_Node (N_Identifier, Sloc (Def));
16464 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16465 Set_Entity (B_Node, Last (Literals (Def)));
16466 Set_Etype (B_Node, T);
16467 Set_Is_Static_Expression (B_Node, True);
16469 Set_High_Bound (R_Node, B_Node);
16471 -- Initialize various fields of the type. Some of this information
16472 -- may be overwritten later through rep.clauses.
16474 Set_Scalar_Range (T, R_Node);
16475 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16476 Set_Enum_Esize (T);
16477 Set_Enum_Pos_To_Rep (T, Empty);
16479 -- Set Discard_Names if configuration pragma set, or if there is
16480 -- a parameterless pragma in the current declarative region
16482 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16483 Set_Discard_Names (T);
16486 -- Process end label if there is one
16488 if Present (Def) then
16489 Process_End_Label (Def, 'e', T);
16491 end Enumeration_Type_Declaration;
16493 ---------------------------------
16494 -- Expand_To_Stored_Constraint --
16495 ---------------------------------
16497 function Expand_To_Stored_Constraint
16499 Constraint : Elist_Id) return Elist_Id
16501 Explicitly_Discriminated_Type : Entity_Id;
16502 Expansion : Elist_Id;
16503 Discriminant : Entity_Id;
16505 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16506 -- Find the nearest type that actually specifies discriminants
16508 ---------------------------------
16509 -- Type_With_Explicit_Discrims --
16510 ---------------------------------
16512 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16513 Typ : constant E := Base_Type (Id);
16516 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16517 if Present (Full_View (Typ)) then
16518 return Type_With_Explicit_Discrims (Full_View (Typ));
16522 if Has_Discriminants (Typ) then
16527 if Etype (Typ) = Typ then
16529 elsif Has_Discriminants (Typ) then
16532 return Type_With_Explicit_Discrims (Etype (Typ));
16535 end Type_With_Explicit_Discrims;
16537 -- Start of processing for Expand_To_Stored_Constraint
16540 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16544 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16546 if No (Explicitly_Discriminated_Type) then
16550 Expansion := New_Elmt_List;
16553 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16554 while Present (Discriminant) loop
16556 (Get_Discriminant_Value
16557 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16559 Next_Stored_Discriminant (Discriminant);
16563 end Expand_To_Stored_Constraint;
16565 ---------------------------
16566 -- Find_Hidden_Interface --
16567 ---------------------------
16569 function Find_Hidden_Interface
16571 Dest : Elist_Id) return Entity_Id
16574 Iface_Elmt : Elmt_Id;
16577 if Present (Src) and then Present (Dest) then
16578 Iface_Elmt := First_Elmt (Src);
16579 while Present (Iface_Elmt) loop
16580 Iface := Node (Iface_Elmt);
16582 if Is_Interface (Iface)
16583 and then not Contain_Interface (Iface, Dest)
16588 Next_Elmt (Iface_Elmt);
16593 end Find_Hidden_Interface;
16595 --------------------
16596 -- Find_Type_Name --
16597 --------------------
16599 function Find_Type_Name (N : Node_Id) return Entity_Id is
16600 Id : constant Entity_Id := Defining_Identifier (N);
16601 New_Id : Entity_Id;
16603 Prev_Par : Node_Id;
16605 procedure Check_Duplicate_Aspects;
16606 -- Check that aspects specified in a completion have not been specified
16607 -- already in the partial view.
16609 procedure Tag_Mismatch;
16610 -- Diagnose a tagged partial view whose full view is untagged. We post
16611 -- the message on the full view, with a reference to the previous
16612 -- partial view. The partial view can be private or incomplete, and
16613 -- these are handled in a different manner, so we determine the position
16614 -- of the error message from the respective slocs of both.
16616 -----------------------------
16617 -- Check_Duplicate_Aspects --
16618 -----------------------------
16620 procedure Check_Duplicate_Aspects is
16621 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id;
16622 -- Return the corresponding aspect of the partial view which matches
16623 -- the aspect id of Asp. Return Empty is no such aspect exists.
16625 -----------------------------
16626 -- Get_Partial_View_Aspect --
16627 -----------------------------
16629 function Get_Partial_View_Aspect (Asp : Node_Id) return Node_Id is
16630 Asp_Id : constant Aspect_Id := Get_Aspect_Id (Asp);
16631 Prev_Asps : constant List_Id := Aspect_Specifications (Prev_Par);
16632 Prev_Asp : Node_Id;
16635 if Present (Prev_Asps) then
16636 Prev_Asp := First (Prev_Asps);
16637 while Present (Prev_Asp) loop
16638 if Get_Aspect_Id (Prev_Asp) = Asp_Id then
16647 end Get_Partial_View_Aspect;
16651 Full_Asps : constant List_Id := Aspect_Specifications (N);
16652 Full_Asp : Node_Id;
16653 Part_Asp : Node_Id;
16655 -- Start of processing for Check_Duplicate_Aspects
16658 if Present (Full_Asps) then
16659 Full_Asp := First (Full_Asps);
16660 while Present (Full_Asp) loop
16661 Part_Asp := Get_Partial_View_Aspect (Full_Asp);
16663 -- An aspect and its class-wide counterpart are two distinct
16664 -- aspects and may apply to both views of an entity.
16666 if Present (Part_Asp)
16667 and then Class_Present (Part_Asp) = Class_Present (Full_Asp)
16670 ("aspect already specified in private declaration",
16677 if Has_Discriminants (Prev)
16678 and then not Has_Unknown_Discriminants (Prev)
16679 and then Get_Aspect_Id (Full_Asp) =
16680 Aspect_Implicit_Dereference
16683 ("cannot specify aspect if partial view has known "
16684 & "discriminants", Full_Asp);
16690 end Check_Duplicate_Aspects;
16696 procedure Tag_Mismatch is
16698 if Sloc (Prev) < Sloc (Id) then
16699 if Ada_Version >= Ada_2012
16700 and then Nkind (N) = N_Private_Type_Declaration
16703 ("declaration of private } must be a tagged type ", Id, Prev);
16706 ("full declaration of } must be a tagged type ", Id, Prev);
16710 if Ada_Version >= Ada_2012
16711 and then Nkind (N) = N_Private_Type_Declaration
16714 ("declaration of private } must be a tagged type ", Prev, Id);
16717 ("full declaration of } must be a tagged type ", Prev, Id);
16722 -- Start of processing for Find_Type_Name
16725 -- Find incomplete declaration, if one was given
16727 Prev := Current_Entity_In_Scope (Id);
16729 -- New type declaration
16735 -- Previous declaration exists
16738 Prev_Par := Parent (Prev);
16740 -- Error if not incomplete/private case except if previous
16741 -- declaration is implicit, etc. Enter_Name will emit error if
16744 if not Is_Incomplete_Or_Private_Type (Prev) then
16748 -- Check invalid completion of private or incomplete type
16750 elsif not Nkind_In (N, N_Full_Type_Declaration,
16751 N_Task_Type_Declaration,
16752 N_Protected_Type_Declaration)
16754 (Ada_Version < Ada_2012
16755 or else not Is_Incomplete_Type (Prev)
16756 or else not Nkind_In (N, N_Private_Type_Declaration,
16757 N_Private_Extension_Declaration))
16759 -- Completion must be a full type declarations (RM 7.3(4))
16761 Error_Msg_Sloc := Sloc (Prev);
16762 Error_Msg_NE ("invalid completion of }", Id, Prev);
16764 -- Set scope of Id to avoid cascaded errors. Entity is never
16765 -- examined again, except when saving globals in generics.
16767 Set_Scope (Id, Current_Scope);
16770 -- If this is a repeated incomplete declaration, no further
16771 -- checks are possible.
16773 if Nkind (N) = N_Incomplete_Type_Declaration then
16777 -- Case of full declaration of incomplete type
16779 elsif Ekind (Prev) = E_Incomplete_Type
16780 and then (Ada_Version < Ada_2012
16781 or else No (Full_View (Prev))
16782 or else not Is_Private_Type (Full_View (Prev)))
16784 -- Indicate that the incomplete declaration has a matching full
16785 -- declaration. The defining occurrence of the incomplete
16786 -- declaration remains the visible one, and the procedure
16787 -- Get_Full_View dereferences it whenever the type is used.
16789 if Present (Full_View (Prev)) then
16790 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16793 Set_Full_View (Prev, Id);
16794 Append_Entity (Id, Current_Scope);
16795 Set_Is_Public (Id, Is_Public (Prev));
16796 Set_Is_Internal (Id);
16799 -- If the incomplete view is tagged, a class_wide type has been
16800 -- created already. Use it for the private type as well, in order
16801 -- to prevent multiple incompatible class-wide types that may be
16802 -- created for self-referential anonymous access components.
16804 if Is_Tagged_Type (Prev)
16805 and then Present (Class_Wide_Type (Prev))
16807 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16808 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16810 -- Type of the class-wide type is the current Id. Previously
16811 -- this was not done for private declarations because of order-
16812 -- of-elaboration issues in the back end, but gigi now handles
16815 Set_Etype (Class_Wide_Type (Id), Id);
16818 -- Case of full declaration of private type
16821 -- If the private type was a completion of an incomplete type then
16822 -- update Prev to reference the private type
16824 if Ada_Version >= Ada_2012
16825 and then Ekind (Prev) = E_Incomplete_Type
16826 and then Present (Full_View (Prev))
16827 and then Is_Private_Type (Full_View (Prev))
16829 Prev := Full_View (Prev);
16830 Prev_Par := Parent (Prev);
16833 if Nkind (N) = N_Full_Type_Declaration
16835 (Type_Definition (N), N_Record_Definition,
16836 N_Derived_Type_Definition)
16837 and then Interface_Present (Type_Definition (N))
16840 ("completion of private type cannot be an interface", N);
16843 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16844 if Etype (Prev) /= Prev then
16846 -- Prev is a private subtype or a derived type, and needs
16849 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16852 elsif Ekind (Prev) = E_Private_Type
16853 and then Nkind_In (N, N_Task_Type_Declaration,
16854 N_Protected_Type_Declaration)
16857 ("completion of nonlimited type cannot be limited", N);
16859 elsif Ekind (Prev) = E_Record_Type_With_Private
16860 and then Nkind_In (N, N_Task_Type_Declaration,
16861 N_Protected_Type_Declaration)
16863 if not Is_Limited_Record (Prev) then
16865 ("completion of nonlimited type cannot be limited", N);
16867 elsif No (Interface_List (N)) then
16869 ("completion of tagged private type must be tagged",
16874 -- Ada 2005 (AI-251): Private extension declaration of a task
16875 -- type or a protected type. This case arises when covering
16876 -- interface types.
16878 elsif Nkind_In (N, N_Task_Type_Declaration,
16879 N_Protected_Type_Declaration)
16883 elsif Nkind (N) /= N_Full_Type_Declaration
16884 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16887 ("full view of private extension must be an extension", N);
16889 elsif not (Abstract_Present (Parent (Prev)))
16890 and then Abstract_Present (Type_Definition (N))
16893 ("full view of non-abstract extension cannot be abstract", N);
16896 if not In_Private_Part (Current_Scope) then
16898 ("declaration of full view must appear in private part", N);
16901 if Ada_Version >= Ada_2012 then
16902 Check_Duplicate_Aspects;
16905 Copy_And_Swap (Prev, Id);
16906 Set_Has_Private_Declaration (Prev);
16907 Set_Has_Private_Declaration (Id);
16909 -- AI12-0133: Indicate whether we have a partial view with
16910 -- unknown discriminants, in which case initialization of objects
16911 -- of the type do not receive an invariant check.
16913 Set_Partial_View_Has_Unknown_Discr
16914 (Prev, Has_Unknown_Discriminants (Id));
16916 -- Preserve aspect and iterator flags that may have been set on
16917 -- the partial view.
16919 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16920 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16922 -- If no error, propagate freeze_node from private to full view.
16923 -- It may have been generated for an early operational item.
16925 if Present (Freeze_Node (Id))
16926 and then Serious_Errors_Detected = 0
16927 and then No (Full_View (Id))
16929 Set_Freeze_Node (Prev, Freeze_Node (Id));
16930 Set_Freeze_Node (Id, Empty);
16931 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16934 Set_Full_View (Id, Prev);
16938 -- Verify that full declaration conforms to partial one
16940 if Is_Incomplete_Or_Private_Type (Prev)
16941 and then Present (Discriminant_Specifications (Prev_Par))
16943 if Present (Discriminant_Specifications (N)) then
16944 if Ekind (Prev) = E_Incomplete_Type then
16945 Check_Discriminant_Conformance (N, Prev, Prev);
16947 Check_Discriminant_Conformance (N, Prev, Id);
16952 ("missing discriminants in full type declaration", N);
16954 -- To avoid cascaded errors on subsequent use, share the
16955 -- discriminants of the partial view.
16957 Set_Discriminant_Specifications (N,
16958 Discriminant_Specifications (Prev_Par));
16962 -- A prior untagged partial view can have an associated class-wide
16963 -- type due to use of the class attribute, and in this case the full
16964 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16965 -- of incomplete tagged declarations, but we check for it.
16968 and then (Is_Tagged_Type (Prev)
16969 or else Present (Class_Wide_Type (Prev)))
16971 -- Ada 2012 (AI05-0162): A private type may be the completion of
16972 -- an incomplete type.
16974 if Ada_Version >= Ada_2012
16975 and then Is_Incomplete_Type (Prev)
16976 and then Nkind_In (N, N_Private_Type_Declaration,
16977 N_Private_Extension_Declaration)
16979 -- No need to check private extensions since they are tagged
16981 if Nkind (N) = N_Private_Type_Declaration
16982 and then not Tagged_Present (N)
16987 -- The full declaration is either a tagged type (including
16988 -- a synchronized type that implements interfaces) or a
16989 -- type extension, otherwise this is an error.
16991 elsif Nkind_In (N, N_Task_Type_Declaration,
16992 N_Protected_Type_Declaration)
16994 if No (Interface_List (N)) and then not Error_Posted (N) then
16998 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
17000 -- Indicate that the previous declaration (tagged incomplete
17001 -- or private declaration) requires the same on the full one.
17003 if not Tagged_Present (Type_Definition (N)) then
17005 Set_Is_Tagged_Type (Id);
17008 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
17009 if No (Record_Extension_Part (Type_Definition (N))) then
17011 ("full declaration of } must be a record extension",
17014 -- Set some attributes to produce a usable full view
17016 Set_Is_Tagged_Type (Id);
17025 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
17026 and then Present (Premature_Use (Parent (Prev)))
17028 Error_Msg_Sloc := Sloc (N);
17030 ("\full declaration #", Premature_Use (Parent (Prev)));
17035 end Find_Type_Name;
17037 -------------------------
17038 -- Find_Type_Of_Object --
17039 -------------------------
17041 function Find_Type_Of_Object
17042 (Obj_Def : Node_Id;
17043 Related_Nod : Node_Id) return Entity_Id
17045 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
17046 P : Node_Id := Parent (Obj_Def);
17051 -- If the parent is a component_definition node we climb to the
17052 -- component_declaration node
17054 if Nkind (P) = N_Component_Definition then
17058 -- Case of an anonymous array subtype
17060 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
17061 N_Unconstrained_Array_Definition)
17064 Array_Type_Declaration (T, Obj_Def);
17066 -- Create an explicit subtype whenever possible
17068 elsif Nkind (P) /= N_Component_Declaration
17069 and then Def_Kind = N_Subtype_Indication
17071 -- Base name of subtype on object name, which will be unique in
17072 -- the current scope.
17074 -- If this is a duplicate declaration, return base type, to avoid
17075 -- generating duplicate anonymous types.
17077 if Error_Posted (P) then
17078 Analyze (Subtype_Mark (Obj_Def));
17079 return Entity (Subtype_Mark (Obj_Def));
17084 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
17086 T := Make_Defining_Identifier (Sloc (P), Nam);
17088 Insert_Action (Obj_Def,
17089 Make_Subtype_Declaration (Sloc (P),
17090 Defining_Identifier => T,
17091 Subtype_Indication => Relocate_Node (Obj_Def)));
17093 -- This subtype may need freezing, and this will not be done
17094 -- automatically if the object declaration is not in declarative
17095 -- part. Since this is an object declaration, the type cannot always
17096 -- be frozen here. Deferred constants do not freeze their type
17097 -- (which often enough will be private).
17099 if Nkind (P) = N_Object_Declaration
17100 and then Constant_Present (P)
17101 and then No (Expression (P))
17105 -- Here we freeze the base type of object type to catch premature use
17106 -- of discriminated private type without a full view.
17109 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
17112 -- Ada 2005 AI-406: the object definition in an object declaration
17113 -- can be an access definition.
17115 elsif Def_Kind = N_Access_Definition then
17116 T := Access_Definition (Related_Nod, Obj_Def);
17118 Set_Is_Local_Anonymous_Access
17120 V => (Ada_Version < Ada_2012)
17121 or else (Nkind (P) /= N_Object_Declaration)
17122 or else Is_Library_Level_Entity (Defining_Identifier (P)));
17124 -- Otherwise, the object definition is just a subtype_mark
17127 T := Process_Subtype (Obj_Def, Related_Nod);
17129 -- If expansion is disabled an object definition that is an aggregate
17130 -- will not get expanded and may lead to scoping problems in the back
17131 -- end, if the object is referenced in an inner scope. In that case
17132 -- create an itype reference for the object definition now. This
17133 -- may be redundant in some cases, but harmless.
17136 and then Nkind (Related_Nod) = N_Object_Declaration
17139 Build_Itype_Reference (T, Related_Nod);
17144 end Find_Type_Of_Object;
17146 --------------------------------
17147 -- Find_Type_Of_Subtype_Indic --
17148 --------------------------------
17150 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
17154 -- Case of subtype mark with a constraint
17156 if Nkind (S) = N_Subtype_Indication then
17157 Find_Type (Subtype_Mark (S));
17158 Typ := Entity (Subtype_Mark (S));
17161 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
17164 ("incorrect constraint for this kind of type", Constraint (S));
17165 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17168 -- Otherwise we have a subtype mark without a constraint
17170 elsif Error_Posted (S) then
17171 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
17179 -- Check No_Wide_Characters restriction
17181 Check_Wide_Character_Restriction (Typ, S);
17184 end Find_Type_Of_Subtype_Indic;
17186 -------------------------------------
17187 -- Floating_Point_Type_Declaration --
17188 -------------------------------------
17190 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17191 Digs : constant Node_Id := Digits_Expression (Def);
17192 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
17194 Base_Typ : Entity_Id;
17195 Implicit_Base : Entity_Id;
17198 function Can_Derive_From (E : Entity_Id) return Boolean;
17199 -- Find if given digits value, and possibly a specified range, allows
17200 -- derivation from specified type
17202 function Find_Base_Type return Entity_Id;
17203 -- Find a predefined base type that Def can derive from, or generate
17204 -- an error and substitute Long_Long_Float if none exists.
17206 ---------------------
17207 -- Can_Derive_From --
17208 ---------------------
17210 function Can_Derive_From (E : Entity_Id) return Boolean is
17211 Spec : constant Entity_Id := Real_Range_Specification (Def);
17214 -- Check specified "digits" constraint
17216 if Digs_Val > Digits_Value (E) then
17220 -- Check for matching range, if specified
17222 if Present (Spec) then
17223 if Expr_Value_R (Type_Low_Bound (E)) >
17224 Expr_Value_R (Low_Bound (Spec))
17229 if Expr_Value_R (Type_High_Bound (E)) <
17230 Expr_Value_R (High_Bound (Spec))
17237 end Can_Derive_From;
17239 --------------------
17240 -- Find_Base_Type --
17241 --------------------
17243 function Find_Base_Type return Entity_Id is
17244 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
17247 -- Iterate over the predefined types in order, returning the first
17248 -- one that Def can derive from.
17250 while Present (Choice) loop
17251 if Can_Derive_From (Node (Choice)) then
17252 return Node (Choice);
17255 Next_Elmt (Choice);
17258 -- If we can't derive from any existing type, use Long_Long_Float
17259 -- and give appropriate message explaining the problem.
17261 if Digs_Val > Max_Digs_Val then
17262 -- It might be the case that there is a type with the requested
17263 -- range, just not the combination of digits and range.
17266 ("no predefined type has requested range and precision",
17267 Real_Range_Specification (Def));
17271 ("range too large for any predefined type",
17272 Real_Range_Specification (Def));
17275 return Standard_Long_Long_Float;
17276 end Find_Base_Type;
17278 -- Start of processing for Floating_Point_Type_Declaration
17281 Check_Restriction (No_Floating_Point, Def);
17283 -- Create an implicit base type
17286 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
17288 -- Analyze and verify digits value
17290 Analyze_And_Resolve (Digs, Any_Integer);
17291 Check_Digits_Expression (Digs);
17292 Digs_Val := Expr_Value (Digs);
17294 -- Process possible range spec and find correct type to derive from
17296 Process_Real_Range_Specification (Def);
17298 -- Check that requested number of digits is not too high.
17300 if Digs_Val > Max_Digs_Val then
17302 -- The check for Max_Base_Digits may be somewhat expensive, as it
17303 -- requires reading System, so only do it when necessary.
17306 Max_Base_Digits : constant Uint :=
17309 (Parent (RTE (RE_Max_Base_Digits))));
17312 if Digs_Val > Max_Base_Digits then
17313 Error_Msg_Uint_1 := Max_Base_Digits;
17314 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
17316 elsif No (Real_Range_Specification (Def)) then
17317 Error_Msg_Uint_1 := Max_Digs_Val;
17318 Error_Msg_N ("types with more than ^ digits need range spec "
17319 & "(RM 3.5.7(6))", Digs);
17324 -- Find a suitable type to derive from or complain and use a substitute
17326 Base_Typ := Find_Base_Type;
17328 -- If there are bounds given in the declaration use them as the bounds
17329 -- of the type, otherwise use the bounds of the predefined base type
17330 -- that was chosen based on the Digits value.
17332 if Present (Real_Range_Specification (Def)) then
17333 Set_Scalar_Range (T, Real_Range_Specification (Def));
17334 Set_Is_Constrained (T);
17336 -- The bounds of this range must be converted to machine numbers
17337 -- in accordance with RM 4.9(38).
17339 Bound := Type_Low_Bound (T);
17341 if Nkind (Bound) = N_Real_Literal then
17343 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17344 Set_Is_Machine_Number (Bound);
17347 Bound := Type_High_Bound (T);
17349 if Nkind (Bound) = N_Real_Literal then
17351 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17352 Set_Is_Machine_Number (Bound);
17356 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17359 -- Complete definition of implicit base and declared first subtype. The
17360 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17361 -- are not clobbered when the floating point type acts as a full view of
17364 Set_Etype (Implicit_Base, Base_Typ);
17365 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17366 Set_Size_Info (Implicit_Base, Base_Typ);
17367 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17368 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17369 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17370 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17372 Set_Ekind (T, E_Floating_Point_Subtype);
17373 Set_Etype (T, Implicit_Base);
17374 Set_Size_Info (T, Implicit_Base);
17375 Set_RM_Size (T, RM_Size (Implicit_Base));
17376 Inherit_Rep_Item_Chain (T, Implicit_Base);
17377 Set_Digits_Value (T, Digs_Val);
17378 end Floating_Point_Type_Declaration;
17380 ----------------------------
17381 -- Get_Discriminant_Value --
17382 ----------------------------
17384 -- This is the situation:
17386 -- There is a non-derived type
17388 -- type T0 (Dx, Dy, Dz...)
17390 -- There are zero or more levels of derivation, with each derivation
17391 -- either purely inheriting the discriminants, or defining its own.
17393 -- type Ti is new Ti-1
17395 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17397 -- subtype Ti is ...
17399 -- The subtype issue is avoided by the use of Original_Record_Component,
17400 -- and the fact that derived subtypes also derive the constraints.
17402 -- This chain leads back from
17404 -- Typ_For_Constraint
17406 -- Typ_For_Constraint has discriminants, and the value for each
17407 -- discriminant is given by its corresponding Elmt of Constraints.
17409 -- Discriminant is some discriminant in this hierarchy
17411 -- We need to return its value
17413 -- We do this by recursively searching each level, and looking for
17414 -- Discriminant. Once we get to the bottom, we start backing up
17415 -- returning the value for it which may in turn be a discriminant
17416 -- further up, so on the backup we continue the substitution.
17418 function Get_Discriminant_Value
17419 (Discriminant : Entity_Id;
17420 Typ_For_Constraint : Entity_Id;
17421 Constraint : Elist_Id) return Node_Id
17423 function Root_Corresponding_Discriminant
17424 (Discr : Entity_Id) return Entity_Id;
17425 -- Given a discriminant, traverse the chain of inherited discriminants
17426 -- and return the topmost discriminant.
17428 function Search_Derivation_Levels
17430 Discrim_Values : Elist_Id;
17431 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17432 -- This is the routine that performs the recursive search of levels
17433 -- as described above.
17435 -------------------------------------
17436 -- Root_Corresponding_Discriminant --
17437 -------------------------------------
17439 function Root_Corresponding_Discriminant
17440 (Discr : Entity_Id) return Entity_Id
17446 while Present (Corresponding_Discriminant (D)) loop
17447 D := Corresponding_Discriminant (D);
17451 end Root_Corresponding_Discriminant;
17453 ------------------------------
17454 -- Search_Derivation_Levels --
17455 ------------------------------
17457 function Search_Derivation_Levels
17459 Discrim_Values : Elist_Id;
17460 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17464 Result : Node_Or_Entity_Id;
17465 Result_Entity : Node_Id;
17468 -- If inappropriate type, return Error, this happens only in
17469 -- cascaded error situations, and we want to avoid a blow up.
17471 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17475 -- Look deeper if possible. Use Stored_Constraints only for
17476 -- untagged types. For tagged types use the given constraint.
17477 -- This asymmetry needs explanation???
17479 if not Stored_Discrim_Values
17480 and then Present (Stored_Constraint (Ti))
17481 and then not Is_Tagged_Type (Ti)
17484 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17487 Td : constant Entity_Id := Etype (Ti);
17491 Result := Discriminant;
17494 if Present (Stored_Constraint (Ti)) then
17496 Search_Derivation_Levels
17497 (Td, Stored_Constraint (Ti), True);
17500 Search_Derivation_Levels
17501 (Td, Discrim_Values, Stored_Discrim_Values);
17507 -- Extra underlying places to search, if not found above. For
17508 -- concurrent types, the relevant discriminant appears in the
17509 -- corresponding record. For a type derived from a private type
17510 -- without discriminant, the full view inherits the discriminants
17511 -- of the full view of the parent.
17513 if Result = Discriminant then
17514 if Is_Concurrent_Type (Ti)
17515 and then Present (Corresponding_Record_Type (Ti))
17518 Search_Derivation_Levels (
17519 Corresponding_Record_Type (Ti),
17521 Stored_Discrim_Values);
17523 elsif Is_Private_Type (Ti)
17524 and then not Has_Discriminants (Ti)
17525 and then Present (Full_View (Ti))
17526 and then Etype (Full_View (Ti)) /= Ti
17529 Search_Derivation_Levels (
17532 Stored_Discrim_Values);
17536 -- If Result is not a (reference to a) discriminant, return it,
17537 -- otherwise set Result_Entity to the discriminant.
17539 if Nkind (Result) = N_Defining_Identifier then
17540 pragma Assert (Result = Discriminant);
17541 Result_Entity := Result;
17544 if not Denotes_Discriminant (Result) then
17548 Result_Entity := Entity (Result);
17551 -- See if this level of derivation actually has discriminants because
17552 -- tagged derivations can add them, hence the lower levels need not
17555 if not Has_Discriminants (Ti) then
17559 -- Scan Ti's discriminants for Result_Entity, and return its
17560 -- corresponding value, if any.
17562 Result_Entity := Original_Record_Component (Result_Entity);
17564 Assoc := First_Elmt (Discrim_Values);
17566 if Stored_Discrim_Values then
17567 Disc := First_Stored_Discriminant (Ti);
17569 Disc := First_Discriminant (Ti);
17572 while Present (Disc) loop
17573 pragma Assert (Present (Assoc));
17575 if Original_Record_Component (Disc) = Result_Entity then
17576 return Node (Assoc);
17581 if Stored_Discrim_Values then
17582 Next_Stored_Discriminant (Disc);
17584 Next_Discriminant (Disc);
17588 -- Could not find it
17591 end Search_Derivation_Levels;
17595 Result : Node_Or_Entity_Id;
17597 -- Start of processing for Get_Discriminant_Value
17600 -- ??? This routine is a gigantic mess and will be deleted. For the
17601 -- time being just test for the trivial case before calling recurse.
17603 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17609 D := First_Discriminant (Typ_For_Constraint);
17610 E := First_Elmt (Constraint);
17611 while Present (D) loop
17612 if Chars (D) = Chars (Discriminant) then
17616 Next_Discriminant (D);
17622 Result := Search_Derivation_Levels
17623 (Typ_For_Constraint, Constraint, False);
17625 -- ??? hack to disappear when this routine is gone
17627 if Nkind (Result) = N_Defining_Identifier then
17633 D := First_Discriminant (Typ_For_Constraint);
17634 E := First_Elmt (Constraint);
17635 while Present (D) loop
17636 if Root_Corresponding_Discriminant (D) = Discriminant then
17640 Next_Discriminant (D);
17646 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17648 end Get_Discriminant_Value;
17650 --------------------------
17651 -- Has_Range_Constraint --
17652 --------------------------
17654 function Has_Range_Constraint (N : Node_Id) return Boolean is
17655 C : constant Node_Id := Constraint (N);
17658 if Nkind (C) = N_Range_Constraint then
17661 elsif Nkind (C) = N_Digits_Constraint then
17663 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17664 or else Present (Range_Constraint (C));
17666 elsif Nkind (C) = N_Delta_Constraint then
17667 return Present (Range_Constraint (C));
17672 end Has_Range_Constraint;
17674 ------------------------
17675 -- Inherit_Components --
17676 ------------------------
17678 function Inherit_Components
17680 Parent_Base : Entity_Id;
17681 Derived_Base : Entity_Id;
17682 Is_Tagged : Boolean;
17683 Inherit_Discr : Boolean;
17684 Discs : Elist_Id) return Elist_Id
17686 Assoc_List : constant Elist_Id := New_Elmt_List;
17688 procedure Inherit_Component
17689 (Old_C : Entity_Id;
17690 Plain_Discrim : Boolean := False;
17691 Stored_Discrim : Boolean := False);
17692 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17693 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17694 -- True, Old_C is a stored discriminant. If they are both false then
17695 -- Old_C is a regular component.
17697 -----------------------
17698 -- Inherit_Component --
17699 -----------------------
17701 procedure Inherit_Component
17702 (Old_C : Entity_Id;
17703 Plain_Discrim : Boolean := False;
17704 Stored_Discrim : Boolean := False)
17706 procedure Set_Anonymous_Type (Id : Entity_Id);
17707 -- Id denotes the entity of an access discriminant or anonymous
17708 -- access component. Set the type of Id to either the same type of
17709 -- Old_C or create a new one depending on whether the parent and
17710 -- the child types are in the same scope.
17712 ------------------------
17713 -- Set_Anonymous_Type --
17714 ------------------------
17716 procedure Set_Anonymous_Type (Id : Entity_Id) is
17717 Old_Typ : constant Entity_Id := Etype (Old_C);
17720 if Scope (Parent_Base) = Scope (Derived_Base) then
17721 Set_Etype (Id, Old_Typ);
17723 -- The parent and the derived type are in two different scopes.
17724 -- Reuse the type of the original discriminant / component by
17725 -- copying it in order to preserve all attributes.
17729 Typ : constant Entity_Id := New_Copy (Old_Typ);
17732 Set_Etype (Id, Typ);
17734 -- Since we do not generate component declarations for
17735 -- inherited components, associate the itype with the
17738 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17739 Set_Scope (Typ, Derived_Base);
17742 end Set_Anonymous_Type;
17744 -- Local variables and constants
17746 New_C : constant Entity_Id := New_Copy (Old_C);
17748 Corr_Discrim : Entity_Id;
17749 Discrim : Entity_Id;
17751 -- Start of processing for Inherit_Component
17754 pragma Assert (not Is_Tagged or not Stored_Discrim);
17756 Set_Parent (New_C, Parent (Old_C));
17758 -- Regular discriminants and components must be inserted in the scope
17759 -- of the Derived_Base. Do it here.
17761 if not Stored_Discrim then
17762 Enter_Name (New_C);
17765 -- For tagged types the Original_Record_Component must point to
17766 -- whatever this field was pointing to in the parent type. This has
17767 -- already been achieved by the call to New_Copy above.
17769 if not Is_Tagged then
17770 Set_Original_Record_Component (New_C, New_C);
17773 -- Set the proper type of an access discriminant
17775 if Ekind (New_C) = E_Discriminant
17776 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17778 Set_Anonymous_Type (New_C);
17781 -- If we have inherited a component then see if its Etype contains
17782 -- references to Parent_Base discriminants. In this case, replace
17783 -- these references with the constraints given in Discs. We do not
17784 -- do this for the partial view of private types because this is
17785 -- not needed (only the components of the full view will be used
17786 -- for code generation) and cause problem. We also avoid this
17787 -- transformation in some error situations.
17789 if Ekind (New_C) = E_Component then
17791 -- Set the proper type of an anonymous access component
17793 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17794 Set_Anonymous_Type (New_C);
17796 elsif (Is_Private_Type (Derived_Base)
17797 and then not Is_Generic_Type (Derived_Base))
17798 or else (Is_Empty_Elmt_List (Discs)
17799 and then not Expander_Active)
17801 Set_Etype (New_C, Etype (Old_C));
17804 -- The current component introduces a circularity of the
17807 -- limited with Pack_2;
17808 -- package Pack_1 is
17809 -- type T_1 is tagged record
17810 -- Comp : access Pack_2.T_2;
17816 -- package Pack_2 is
17817 -- type T_2 is new Pack_1.T_1 with ...;
17822 Constrain_Component_Type
17823 (Old_C, Derived_Base, N, Parent_Base, Discs));
17827 -- In derived tagged types it is illegal to reference a non
17828 -- discriminant component in the parent type. To catch this, mark
17829 -- these components with an Ekind of E_Void. This will be reset in
17830 -- Record_Type_Definition after processing the record extension of
17831 -- the derived type.
17833 -- If the declaration is a private extension, there is no further
17834 -- record extension to process, and the components retain their
17835 -- current kind, because they are visible at this point.
17837 if Is_Tagged and then Ekind (New_C) = E_Component
17838 and then Nkind (N) /= N_Private_Extension_Declaration
17840 Set_Ekind (New_C, E_Void);
17843 if Plain_Discrim then
17844 Set_Corresponding_Discriminant (New_C, Old_C);
17845 Build_Discriminal (New_C);
17847 -- If we are explicitly inheriting a stored discriminant it will be
17848 -- completely hidden.
17850 elsif Stored_Discrim then
17851 Set_Corresponding_Discriminant (New_C, Empty);
17852 Set_Discriminal (New_C, Empty);
17853 Set_Is_Completely_Hidden (New_C);
17855 -- Set the Original_Record_Component of each discriminant in the
17856 -- derived base to point to the corresponding stored that we just
17859 Discrim := First_Discriminant (Derived_Base);
17860 while Present (Discrim) loop
17861 Corr_Discrim := Corresponding_Discriminant (Discrim);
17863 -- Corr_Discrim could be missing in an error situation
17865 if Present (Corr_Discrim)
17866 and then Original_Record_Component (Corr_Discrim) = Old_C
17868 Set_Original_Record_Component (Discrim, New_C);
17871 Next_Discriminant (Discrim);
17874 Append_Entity (New_C, Derived_Base);
17877 if not Is_Tagged then
17878 Append_Elmt (Old_C, Assoc_List);
17879 Append_Elmt (New_C, Assoc_List);
17881 end Inherit_Component;
17883 -- Variables local to Inherit_Component
17885 Loc : constant Source_Ptr := Sloc (N);
17887 Parent_Discrim : Entity_Id;
17888 Stored_Discrim : Entity_Id;
17890 Component : Entity_Id;
17892 -- Start of processing for Inherit_Components
17895 if not Is_Tagged then
17896 Append_Elmt (Parent_Base, Assoc_List);
17897 Append_Elmt (Derived_Base, Assoc_List);
17900 -- Inherit parent discriminants if needed
17902 if Inherit_Discr then
17903 Parent_Discrim := First_Discriminant (Parent_Base);
17904 while Present (Parent_Discrim) loop
17905 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17906 Next_Discriminant (Parent_Discrim);
17910 -- Create explicit stored discrims for untagged types when necessary
17912 if not Has_Unknown_Discriminants (Derived_Base)
17913 and then Has_Discriminants (Parent_Base)
17914 and then not Is_Tagged
17917 or else First_Discriminant (Parent_Base) /=
17918 First_Stored_Discriminant (Parent_Base))
17920 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17921 while Present (Stored_Discrim) loop
17922 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17923 Next_Stored_Discriminant (Stored_Discrim);
17927 -- See if we can apply the second transformation for derived types, as
17928 -- explained in point 6. in the comments above Build_Derived_Record_Type
17929 -- This is achieved by appending Derived_Base discriminants into Discs,
17930 -- which has the side effect of returning a non empty Discs list to the
17931 -- caller of Inherit_Components, which is what we want. This must be
17932 -- done for private derived types if there are explicit stored
17933 -- discriminants, to ensure that we can retrieve the values of the
17934 -- constraints provided in the ancestors.
17937 and then Is_Empty_Elmt_List (Discs)
17938 and then Present (First_Discriminant (Derived_Base))
17940 (not Is_Private_Type (Derived_Base)
17941 or else Is_Completely_Hidden
17942 (First_Stored_Discriminant (Derived_Base))
17943 or else Is_Generic_Type (Derived_Base))
17945 D := First_Discriminant (Derived_Base);
17946 while Present (D) loop
17947 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17948 Next_Discriminant (D);
17952 -- Finally, inherit non-discriminant components unless they are not
17953 -- visible because defined or inherited from the full view of the
17954 -- parent. Don't inherit the _parent field of the parent type.
17956 Component := First_Entity (Parent_Base);
17957 while Present (Component) loop
17959 -- Ada 2005 (AI-251): Do not inherit components associated with
17960 -- secondary tags of the parent.
17962 if Ekind (Component) = E_Component
17963 and then Present (Related_Type (Component))
17967 elsif Ekind (Component) /= E_Component
17968 or else Chars (Component) = Name_uParent
17972 -- If the derived type is within the parent type's declarative
17973 -- region, then the components can still be inherited even though
17974 -- they aren't visible at this point. This can occur for cases
17975 -- such as within public child units where the components must
17976 -- become visible upon entering the child unit's private part.
17978 elsif not Is_Visible_Component (Component)
17979 and then not In_Open_Scopes (Scope (Parent_Base))
17983 elsif Ekind_In (Derived_Base, E_Private_Type,
17984 E_Limited_Private_Type)
17989 Inherit_Component (Component);
17992 Next_Entity (Component);
17995 -- For tagged derived types, inherited discriminants cannot be used in
17996 -- component declarations of the record extension part. To achieve this
17997 -- we mark the inherited discriminants as not visible.
17999 if Is_Tagged and then Inherit_Discr then
18000 D := First_Discriminant (Derived_Base);
18001 while Present (D) loop
18002 Set_Is_Immediately_Visible (D, False);
18003 Next_Discriminant (D);
18008 end Inherit_Components;
18010 -----------------------------
18011 -- Inherit_Predicate_Flags --
18012 -----------------------------
18014 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
18016 Set_Has_Predicates (Subt, Has_Predicates (Par));
18017 Set_Has_Static_Predicate_Aspect
18018 (Subt, Has_Static_Predicate_Aspect (Par));
18019 Set_Has_Dynamic_Predicate_Aspect
18020 (Subt, Has_Dynamic_Predicate_Aspect (Par));
18021 end Inherit_Predicate_Flags;
18023 ----------------------
18024 -- Is_EVF_Procedure --
18025 ----------------------
18027 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
18028 Formal : Entity_Id;
18031 -- Examine the formals of an Extensions_Visible False procedure looking
18032 -- for a controlling OUT parameter.
18034 if Ekind (Subp) = E_Procedure
18035 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
18037 Formal := First_Formal (Subp);
18038 while Present (Formal) loop
18039 if Ekind (Formal) = E_Out_Parameter
18040 and then Is_Controlling_Formal (Formal)
18045 Next_Formal (Formal);
18050 end Is_EVF_Procedure;
18052 -----------------------
18053 -- Is_Null_Extension --
18054 -----------------------
18056 function Is_Null_Extension (T : Entity_Id) return Boolean is
18057 Type_Decl : constant Node_Id := Parent (Base_Type (T));
18058 Comp_List : Node_Id;
18062 if Nkind (Type_Decl) /= N_Full_Type_Declaration
18063 or else not Is_Tagged_Type (T)
18064 or else Nkind (Type_Definition (Type_Decl)) /=
18065 N_Derived_Type_Definition
18066 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
18072 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
18074 if Present (Discriminant_Specifications (Type_Decl)) then
18077 elsif Present (Comp_List)
18078 and then Is_Non_Empty_List (Component_Items (Comp_List))
18080 Comp := First (Component_Items (Comp_List));
18082 -- Only user-defined components are relevant. The component list
18083 -- may also contain a parent component and internal components
18084 -- corresponding to secondary tags, but these do not determine
18085 -- whether this is a null extension.
18087 while Present (Comp) loop
18088 if Comes_From_Source (Comp) then
18100 end Is_Null_Extension;
18102 ------------------------------
18103 -- Is_Valid_Constraint_Kind --
18104 ------------------------------
18106 function Is_Valid_Constraint_Kind
18107 (T_Kind : Type_Kind;
18108 Constraint_Kind : Node_Kind) return Boolean
18112 when Enumeration_Kind
18115 return Constraint_Kind = N_Range_Constraint;
18117 when Decimal_Fixed_Point_Kind =>
18118 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18119 N_Range_Constraint);
18121 when Ordinary_Fixed_Point_Kind =>
18122 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
18123 N_Range_Constraint);
18126 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
18127 N_Range_Constraint);
18134 | E_Incomplete_Type
18138 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
18141 return True; -- Error will be detected later
18143 end Is_Valid_Constraint_Kind;
18145 --------------------------
18146 -- Is_Visible_Component --
18147 --------------------------
18149 function Is_Visible_Component
18151 N : Node_Id := Empty) return Boolean
18153 Original_Comp : Entity_Id := Empty;
18154 Original_Type : Entity_Id;
18155 Type_Scope : Entity_Id;
18157 function Is_Local_Type (Typ : Entity_Id) return Boolean;
18158 -- Check whether parent type of inherited component is declared locally,
18159 -- possibly within a nested package or instance. The current scope is
18160 -- the derived record itself.
18162 -------------------
18163 -- Is_Local_Type --
18164 -------------------
18166 function Is_Local_Type (Typ : Entity_Id) return Boolean is
18170 Scop := Scope (Typ);
18171 while Present (Scop)
18172 and then Scop /= Standard_Standard
18174 if Scop = Scope (Current_Scope) then
18178 Scop := Scope (Scop);
18184 -- Start of processing for Is_Visible_Component
18187 if Ekind_In (C, E_Component, E_Discriminant) then
18188 Original_Comp := Original_Record_Component (C);
18191 if No (Original_Comp) then
18193 -- Premature usage, or previous error
18198 Original_Type := Scope (Original_Comp);
18199 Type_Scope := Scope (Base_Type (Scope (C)));
18202 -- This test only concerns tagged types
18204 if not Is_Tagged_Type (Original_Type) then
18207 -- If it is _Parent or _Tag, there is no visibility issue
18209 elsif not Comes_From_Source (Original_Comp) then
18212 -- Discriminants are visible unless the (private) type has unknown
18213 -- discriminants. If the discriminant reference is inserted for a
18214 -- discriminant check on a full view it is also visible.
18216 elsif Ekind (Original_Comp) = E_Discriminant
18218 (not Has_Unknown_Discriminants (Original_Type)
18219 or else (Present (N)
18220 and then Nkind (N) = N_Selected_Component
18221 and then Nkind (Prefix (N)) = N_Type_Conversion
18222 and then not Comes_From_Source (Prefix (N))))
18226 -- In the body of an instantiation, check the visibility of a component
18227 -- in case it has a homograph that is a primitive operation of a private
18228 -- type which was not visible in the generic unit.
18230 -- Should Is_Prefixed_Call be propagated from template to instance???
18232 elsif In_Instance_Body then
18233 if not Is_Tagged_Type (Original_Type)
18234 or else not Is_Private_Type (Original_Type)
18240 Subp_Elmt : Elmt_Id;
18243 Subp_Elmt := First_Elmt (Primitive_Operations (Original_Type));
18244 while Present (Subp_Elmt) loop
18246 -- The component is hidden by a primitive operation
18248 if Chars (Node (Subp_Elmt)) = Chars (C) then
18252 Next_Elmt (Subp_Elmt);
18259 -- If the component has been declared in an ancestor which is currently
18260 -- a private type, then it is not visible. The same applies if the
18261 -- component's containing type is not in an open scope and the original
18262 -- component's enclosing type is a visible full view of a private type
18263 -- (which can occur in cases where an attempt is being made to reference
18264 -- a component in a sibling package that is inherited from a visible
18265 -- component of a type in an ancestor package; the component in the
18266 -- sibling package should not be visible even though the component it
18267 -- inherited from is visible). This does not apply however in the case
18268 -- where the scope of the type is a private child unit, or when the
18269 -- parent comes from a local package in which the ancestor is currently
18270 -- visible. The latter suppression of visibility is needed for cases
18271 -- that are tested in B730006.
18273 elsif Is_Private_Type (Original_Type)
18275 (not Is_Private_Descendant (Type_Scope)
18276 and then not In_Open_Scopes (Type_Scope)
18277 and then Has_Private_Declaration (Original_Type))
18279 -- If the type derives from an entity in a formal package, there
18280 -- are no additional visible components.
18282 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
18283 N_Formal_Package_Declaration
18287 -- if we are not in the private part of the current package, there
18288 -- are no additional visible components.
18290 elsif Ekind (Scope (Current_Scope)) = E_Package
18291 and then not In_Private_Part (Scope (Current_Scope))
18296 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
18297 and then In_Open_Scopes (Scope (Original_Type))
18298 and then Is_Local_Type (Type_Scope);
18301 -- There is another weird way in which a component may be invisible when
18302 -- the private and the full view are not derived from the same ancestor.
18303 -- Here is an example :
18305 -- type A1 is tagged record F1 : integer; end record;
18306 -- type A2 is new A1 with record F2 : integer; end record;
18307 -- type T is new A1 with private;
18309 -- type T is new A2 with null record;
18311 -- In this case, the full view of T inherits F1 and F2 but the private
18312 -- view inherits only F1
18316 Ancestor : Entity_Id := Scope (C);
18320 if Ancestor = Original_Type then
18323 -- The ancestor may have a partial view of the original type,
18324 -- but if the full view is in scope, as in a child body, the
18325 -- component is visible.
18327 elsif In_Private_Part (Scope (Original_Type))
18328 and then Full_View (Ancestor) = Original_Type
18332 elsif Ancestor = Etype (Ancestor) then
18334 -- No further ancestors to examine
18339 Ancestor := Etype (Ancestor);
18343 end Is_Visible_Component;
18345 --------------------------
18346 -- Make_Class_Wide_Type --
18347 --------------------------
18349 procedure Make_Class_Wide_Type (T : Entity_Id) is
18350 CW_Type : Entity_Id;
18352 Next_E : Entity_Id;
18355 if Present (Class_Wide_Type (T)) then
18357 -- The class-wide type is a partially decorated entity created for a
18358 -- unanalyzed tagged type referenced through a limited with clause.
18359 -- When the tagged type is analyzed, its class-wide type needs to be
18360 -- redecorated. Note that we reuse the entity created by Decorate_
18361 -- Tagged_Type in order to preserve all links.
18363 if Materialize_Entity (Class_Wide_Type (T)) then
18364 CW_Type := Class_Wide_Type (T);
18365 Set_Materialize_Entity (CW_Type, False);
18367 -- The class wide type can have been defined by the partial view, in
18368 -- which case everything is already done.
18374 -- Default case, we need to create a new class-wide type
18378 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18381 -- Inherit root type characteristics
18383 CW_Name := Chars (CW_Type);
18384 Next_E := Next_Entity (CW_Type);
18385 Copy_Node (T, CW_Type);
18386 Set_Comes_From_Source (CW_Type, False);
18387 Set_Chars (CW_Type, CW_Name);
18388 Set_Parent (CW_Type, Parent (T));
18389 Set_Next_Entity (CW_Type, Next_E);
18391 -- Ensure we have a new freeze node for the class-wide type. The partial
18392 -- view may have freeze action of its own, requiring a proper freeze
18393 -- node, and the same freeze node cannot be shared between the two
18396 Set_Has_Delayed_Freeze (CW_Type);
18397 Set_Freeze_Node (CW_Type, Empty);
18399 -- Customize the class-wide type: It has no prim. op., it cannot be
18400 -- abstract, its Etype points back to the specific root type, and it
18401 -- cannot have any invariants.
18403 Set_Ekind (CW_Type, E_Class_Wide_Type);
18404 Set_Is_Tagged_Type (CW_Type, True);
18405 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18406 Set_Is_Abstract_Type (CW_Type, False);
18407 Set_Is_Constrained (CW_Type, False);
18408 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18409 Set_Default_SSO (CW_Type);
18410 Set_Has_Inheritable_Invariants (CW_Type, False);
18411 Set_Has_Inherited_Invariants (CW_Type, False);
18412 Set_Has_Own_Invariants (CW_Type, False);
18414 if Ekind (T) = E_Class_Wide_Subtype then
18415 Set_Etype (CW_Type, Etype (Base_Type (T)));
18417 Set_Etype (CW_Type, T);
18420 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18422 -- If this is the class_wide type of a constrained subtype, it does
18423 -- not have discriminants.
18425 Set_Has_Discriminants (CW_Type,
18426 Has_Discriminants (T) and then not Is_Constrained (T));
18428 Set_Has_Unknown_Discriminants (CW_Type, True);
18429 Set_Class_Wide_Type (T, CW_Type);
18430 Set_Equivalent_Type (CW_Type, Empty);
18432 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18434 Set_Class_Wide_Type (CW_Type, CW_Type);
18435 end Make_Class_Wide_Type;
18441 procedure Make_Index
18443 Related_Nod : Node_Id;
18444 Related_Id : Entity_Id := Empty;
18445 Suffix_Index : Nat := 1;
18446 In_Iter_Schm : Boolean := False)
18450 Def_Id : Entity_Id := Empty;
18451 Found : Boolean := False;
18454 -- For a discrete range used in a constrained array definition and
18455 -- defined by a range, an implicit conversion to the predefined type
18456 -- INTEGER is assumed if each bound is either a numeric literal, a named
18457 -- number, or an attribute, and the type of both bounds (prior to the
18458 -- implicit conversion) is the type universal_integer. Otherwise, both
18459 -- bounds must be of the same discrete type, other than universal
18460 -- integer; this type must be determinable independently of the
18461 -- context, but using the fact that the type must be discrete and that
18462 -- both bounds must have the same type.
18464 -- Character literals also have a universal type in the absence of
18465 -- of additional context, and are resolved to Standard_Character.
18467 if Nkind (N) = N_Range then
18469 -- The index is given by a range constraint. The bounds are known
18470 -- to be of a consistent type.
18472 if not Is_Overloaded (N) then
18475 -- For universal bounds, choose the specific predefined type
18477 if T = Universal_Integer then
18478 T := Standard_Integer;
18480 elsif T = Any_Character then
18481 Ambiguous_Character (Low_Bound (N));
18483 T := Standard_Character;
18486 -- The node may be overloaded because some user-defined operators
18487 -- are available, but if a universal interpretation exists it is
18488 -- also the selected one.
18490 elsif Universal_Interpretation (N) = Universal_Integer then
18491 T := Standard_Integer;
18497 Ind : Interp_Index;
18501 Get_First_Interp (N, Ind, It);
18502 while Present (It.Typ) loop
18503 if Is_Discrete_Type (It.Typ) then
18506 and then not Covers (It.Typ, T)
18507 and then not Covers (T, It.Typ)
18509 Error_Msg_N ("ambiguous bounds in discrete range", N);
18517 Get_Next_Interp (Ind, It);
18520 if T = Any_Type then
18521 Error_Msg_N ("discrete type required for range", N);
18522 Set_Etype (N, Any_Type);
18525 elsif T = Universal_Integer then
18526 T := Standard_Integer;
18531 if not Is_Discrete_Type (T) then
18532 Error_Msg_N ("discrete type required for range", N);
18533 Set_Etype (N, Any_Type);
18537 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18538 and then Attribute_Name (Low_Bound (N)) = Name_First
18539 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18540 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18541 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18543 -- The type of the index will be the type of the prefix, as long
18544 -- as the upper bound is 'Last of the same type.
18546 Def_Id := Entity (Prefix (Low_Bound (N)));
18548 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18549 or else Attribute_Name (High_Bound (N)) /= Name_Last
18550 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18551 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18558 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18560 elsif Nkind (N) = N_Subtype_Indication then
18562 -- The index is given by a subtype with a range constraint
18564 T := Base_Type (Entity (Subtype_Mark (N)));
18566 if not Is_Discrete_Type (T) then
18567 Error_Msg_N ("discrete type required for range", N);
18568 Set_Etype (N, Any_Type);
18572 R := Range_Expression (Constraint (N));
18575 Process_Range_Expr_In_Decl
18576 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18578 elsif Nkind (N) = N_Attribute_Reference then
18580 -- Catch beginner's error (use of attribute other than 'Range)
18582 if Attribute_Name (N) /= Name_Range then
18583 Error_Msg_N ("expect attribute ''Range", N);
18584 Set_Etype (N, Any_Type);
18588 -- If the node denotes the range of a type mark, that is also the
18589 -- resulting type, and we do not need to create an Itype for it.
18591 if Is_Entity_Name (Prefix (N))
18592 and then Comes_From_Source (N)
18593 and then Is_Type (Entity (Prefix (N)))
18594 and then Is_Discrete_Type (Entity (Prefix (N)))
18596 Def_Id := Entity (Prefix (N));
18599 Analyze_And_Resolve (N);
18603 -- If none of the above, must be a subtype. We convert this to a
18604 -- range attribute reference because in the case of declared first
18605 -- named subtypes, the types in the range reference can be different
18606 -- from the type of the entity. A range attribute normalizes the
18607 -- reference and obtains the correct types for the bounds.
18609 -- This transformation is in the nature of an expansion, is only
18610 -- done if expansion is active. In particular, it is not done on
18611 -- formal generic types, because we need to retain the name of the
18612 -- original index for instantiation purposes.
18615 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18616 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18617 Set_Etype (N, Any_Integer);
18621 -- The type mark may be that of an incomplete type. It is only
18622 -- now that we can get the full view, previous analysis does
18623 -- not look specifically for a type mark.
18625 Set_Entity (N, Get_Full_View (Entity (N)));
18626 Set_Etype (N, Entity (N));
18627 Def_Id := Entity (N);
18629 if not Is_Discrete_Type (Def_Id) then
18630 Error_Msg_N ("discrete type required for index", N);
18631 Set_Etype (N, Any_Type);
18636 if Expander_Active then
18638 Make_Attribute_Reference (Sloc (N),
18639 Attribute_Name => Name_Range,
18640 Prefix => Relocate_Node (N)));
18642 -- The original was a subtype mark that does not freeze. This
18643 -- means that the rewritten version must not freeze either.
18645 Set_Must_Not_Freeze (N);
18646 Set_Must_Not_Freeze (Prefix (N));
18647 Analyze_And_Resolve (N);
18651 -- If expander is inactive, type is legal, nothing else to construct
18658 if not Is_Discrete_Type (T) then
18659 Error_Msg_N ("discrete type required for range", N);
18660 Set_Etype (N, Any_Type);
18663 elsif T = Any_Type then
18664 Set_Etype (N, Any_Type);
18668 -- We will now create the appropriate Itype to describe the range, but
18669 -- first a check. If we originally had a subtype, then we just label
18670 -- the range with this subtype. Not only is there no need to construct
18671 -- a new subtype, but it is wrong to do so for two reasons:
18673 -- 1. A legality concern, if we have a subtype, it must not freeze,
18674 -- and the Itype would cause freezing incorrectly
18676 -- 2. An efficiency concern, if we created an Itype, it would not be
18677 -- recognized as the same type for the purposes of eliminating
18678 -- checks in some circumstances.
18680 -- We signal this case by setting the subtype entity in Def_Id
18682 if No (Def_Id) then
18684 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18685 Set_Etype (Def_Id, Base_Type (T));
18687 if Is_Signed_Integer_Type (T) then
18688 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18690 elsif Is_Modular_Integer_Type (T) then
18691 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18694 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18695 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18696 Set_First_Literal (Def_Id, First_Literal (T));
18699 Set_Size_Info (Def_Id, (T));
18700 Set_RM_Size (Def_Id, RM_Size (T));
18701 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18703 Set_Scalar_Range (Def_Id, R);
18704 Conditional_Delay (Def_Id, T);
18706 if Nkind (N) = N_Subtype_Indication then
18707 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18710 -- In the subtype indication case, if the immediate parent of the
18711 -- new subtype is non-static, then the subtype we create is non-
18712 -- static, even if its bounds are static.
18714 if Nkind (N) = N_Subtype_Indication
18715 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18717 Set_Is_Non_Static_Subtype (Def_Id);
18721 -- Final step is to label the index with this constructed type
18723 Set_Etype (N, Def_Id);
18726 ------------------------------
18727 -- Modular_Type_Declaration --
18728 ------------------------------
18730 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18731 Mod_Expr : constant Node_Id := Expression (Def);
18734 procedure Set_Modular_Size (Bits : Int);
18735 -- Sets RM_Size to Bits, and Esize to normal word size above this
18737 ----------------------
18738 -- Set_Modular_Size --
18739 ----------------------
18741 procedure Set_Modular_Size (Bits : Int) is
18743 Set_RM_Size (T, UI_From_Int (Bits));
18748 elsif Bits <= 16 then
18749 Init_Esize (T, 16);
18751 elsif Bits <= 32 then
18752 Init_Esize (T, 32);
18755 Init_Esize (T, System_Max_Binary_Modulus_Power);
18758 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18759 Set_Is_Known_Valid (T);
18761 end Set_Modular_Size;
18763 -- Start of processing for Modular_Type_Declaration
18766 -- If the mod expression is (exactly) 2 * literal, where literal is
18767 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18769 if Warn_On_Suspicious_Modulus_Value
18770 and then Nkind (Mod_Expr) = N_Op_Multiply
18771 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18772 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18773 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18774 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18777 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18780 -- Proceed with analysis of mod expression
18782 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18784 Set_Ekind (T, E_Modular_Integer_Type);
18785 Init_Alignment (T);
18786 Set_Is_Constrained (T);
18788 if not Is_OK_Static_Expression (Mod_Expr) then
18789 Flag_Non_Static_Expr
18790 ("non-static expression used for modular type bound!", Mod_Expr);
18791 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18793 M_Val := Expr_Value (Mod_Expr);
18797 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18798 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18801 if M_Val > 2 ** Standard_Long_Integer_Size then
18802 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18805 Set_Modulus (T, M_Val);
18807 -- Create bounds for the modular type based on the modulus given in
18808 -- the type declaration and then analyze and resolve those bounds.
18810 Set_Scalar_Range (T,
18811 Make_Range (Sloc (Mod_Expr),
18812 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18813 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18815 -- Properly analyze the literals for the range. We do this manually
18816 -- because we can't go calling Resolve, since we are resolving these
18817 -- bounds with the type, and this type is certainly not complete yet.
18819 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18820 Set_Etype (High_Bound (Scalar_Range (T)), T);
18821 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18822 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18824 -- Loop through powers of two to find number of bits required
18826 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18830 if M_Val = 2 ** Bits then
18831 Set_Modular_Size (Bits);
18836 elsif M_Val < 2 ** Bits then
18837 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18838 Set_Non_Binary_Modulus (T);
18840 if Bits > System_Max_Nonbinary_Modulus_Power then
18841 Error_Msg_Uint_1 :=
18842 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18844 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18845 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18849 -- In the nonbinary case, set size as per RM 13.3(55)
18851 Set_Modular_Size (Bits);
18858 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18859 -- so we just signal an error and set the maximum size.
18861 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18862 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18864 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18865 Init_Alignment (T);
18867 end Modular_Type_Declaration;
18869 --------------------------
18870 -- New_Concatenation_Op --
18871 --------------------------
18873 procedure New_Concatenation_Op (Typ : Entity_Id) is
18874 Loc : constant Source_Ptr := Sloc (Typ);
18877 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18878 -- Create abbreviated declaration for the formal of a predefined
18879 -- Operator 'Op' of type 'Typ'
18881 --------------------
18882 -- Make_Op_Formal --
18883 --------------------
18885 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18886 Formal : Entity_Id;
18888 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18889 Set_Etype (Formal, Typ);
18890 Set_Mechanism (Formal, Default_Mechanism);
18892 end Make_Op_Formal;
18894 -- Start of processing for New_Concatenation_Op
18897 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18899 Set_Ekind (Op, E_Operator);
18900 Set_Scope (Op, Current_Scope);
18901 Set_Etype (Op, Typ);
18902 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18903 Set_Is_Immediately_Visible (Op);
18904 Set_Is_Intrinsic_Subprogram (Op);
18905 Set_Has_Completion (Op);
18906 Append_Entity (Op, Current_Scope);
18908 Set_Name_Entity_Id (Name_Op_Concat, Op);
18910 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18911 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18912 end New_Concatenation_Op;
18914 -------------------------
18915 -- OK_For_Limited_Init --
18916 -------------------------
18918 -- ???Check all calls of this, and compare the conditions under which it's
18921 function OK_For_Limited_Init
18923 Exp : Node_Id) return Boolean
18926 return Is_CPP_Constructor_Call (Exp)
18927 or else (Ada_Version >= Ada_2005
18928 and then not Debug_Flag_Dot_L
18929 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18930 end OK_For_Limited_Init;
18932 -------------------------------
18933 -- OK_For_Limited_Init_In_05 --
18934 -------------------------------
18936 function OK_For_Limited_Init_In_05
18938 Exp : Node_Id) return Boolean
18941 -- An object of a limited interface type can be initialized with any
18942 -- expression of a nonlimited descendant type. However this does not
18943 -- apply if this is a view conversion of some other expression. This
18944 -- is checked below.
18946 if Is_Class_Wide_Type (Typ)
18947 and then Is_Limited_Interface (Typ)
18948 and then not Is_Limited_Type (Etype (Exp))
18949 and then Nkind (Exp) /= N_Type_Conversion
18954 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18955 -- case of limited aggregates (including extension aggregates), and
18956 -- function calls. The function call may have been given in prefixed
18957 -- notation, in which case the original node is an indexed component.
18958 -- If the function is parameterless, the original node was an explicit
18959 -- dereference. The function may also be parameterless, in which case
18960 -- the source node is just an identifier.
18962 -- A branch of a conditional expression may have been removed if the
18963 -- condition is statically known. This happens during expansion, and
18964 -- thus will not happen if previous errors were encountered. The check
18965 -- will have been performed on the chosen branch, which replaces the
18966 -- original conditional expression.
18972 case Nkind (Original_Node (Exp)) is
18974 | N_Extension_Aggregate
18980 when N_Identifier =>
18981 return Present (Entity (Original_Node (Exp)))
18982 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18984 when N_Qualified_Expression =>
18986 OK_For_Limited_Init_In_05
18987 (Typ, Expression (Original_Node (Exp)));
18989 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18990 -- with a function call, the expander has rewritten the call into an
18991 -- N_Type_Conversion node to force displacement of the pointer to
18992 -- reference the component containing the secondary dispatch table.
18993 -- Otherwise a type conversion is not a legal context.
18994 -- A return statement for a build-in-place function returning a
18995 -- synchronized type also introduces an unchecked conversion.
18997 when N_Type_Conversion
18998 | N_Unchecked_Type_Conversion
19000 return not Comes_From_Source (Exp)
19002 OK_For_Limited_Init_In_05
19003 (Typ, Expression (Original_Node (Exp)));
19005 when N_Explicit_Dereference
19006 | N_Indexed_Component
19007 | N_Selected_Component
19009 return Nkind (Exp) = N_Function_Call;
19011 -- A use of 'Input is a function call, hence allowed. Normally the
19012 -- attribute will be changed to a call, but the attribute by itself
19013 -- can occur with -gnatc.
19015 when N_Attribute_Reference =>
19016 return Attribute_Name (Original_Node (Exp)) = Name_Input;
19018 -- For a case expression, all dependent expressions must be legal
19020 when N_Case_Expression =>
19025 Alt := First (Alternatives (Original_Node (Exp)));
19026 while Present (Alt) loop
19027 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
19037 -- For an if expression, all dependent expressions must be legal
19039 when N_If_Expression =>
19041 Then_Expr : constant Node_Id :=
19042 Next (First (Expressions (Original_Node (Exp))));
19043 Else_Expr : constant Node_Id := Next (Then_Expr);
19045 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
19047 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
19053 end OK_For_Limited_Init_In_05;
19055 -------------------------------------------
19056 -- Ordinary_Fixed_Point_Type_Declaration --
19057 -------------------------------------------
19059 procedure Ordinary_Fixed_Point_Type_Declaration
19063 Loc : constant Source_Ptr := Sloc (Def);
19064 Delta_Expr : constant Node_Id := Delta_Expression (Def);
19065 RRS : constant Node_Id := Real_Range_Specification (Def);
19066 Implicit_Base : Entity_Id;
19073 Check_Restriction (No_Fixed_Point, Def);
19075 -- Create implicit base type
19078 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
19079 Set_Etype (Implicit_Base, Implicit_Base);
19081 -- Analyze and process delta expression
19083 Analyze_And_Resolve (Delta_Expr, Any_Real);
19085 Check_Delta_Expression (Delta_Expr);
19086 Delta_Val := Expr_Value_R (Delta_Expr);
19088 Set_Delta_Value (Implicit_Base, Delta_Val);
19090 -- Compute default small from given delta, which is the largest power
19091 -- of two that does not exceed the given delta value.
19101 if Delta_Val < Ureal_1 then
19102 while Delta_Val < Tmp loop
19103 Tmp := Tmp / Ureal_2;
19104 Scale := Scale + 1;
19109 Tmp := Tmp * Ureal_2;
19110 exit when Tmp > Delta_Val;
19111 Scale := Scale - 1;
19115 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
19118 Set_Small_Value (Implicit_Base, Small_Val);
19120 -- If no range was given, set a dummy range
19122 if RRS <= Empty_Or_Error then
19123 Low_Val := -Small_Val;
19124 High_Val := Small_Val;
19126 -- Otherwise analyze and process given range
19130 Low : constant Node_Id := Low_Bound (RRS);
19131 High : constant Node_Id := High_Bound (RRS);
19134 Analyze_And_Resolve (Low, Any_Real);
19135 Analyze_And_Resolve (High, Any_Real);
19136 Check_Real_Bound (Low);
19137 Check_Real_Bound (High);
19139 -- Obtain and set the range
19141 Low_Val := Expr_Value_R (Low);
19142 High_Val := Expr_Value_R (High);
19144 if Low_Val > High_Val then
19145 Error_Msg_NE ("??fixed point type& has null range", Def, T);
19150 -- The range for both the implicit base and the declared first subtype
19151 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
19152 -- set a temporary range in place. Note that the bounds of the base
19153 -- type will be widened to be symmetrical and to fill the available
19154 -- bits when the type is frozen.
19156 -- We could do this with all discrete types, and probably should, but
19157 -- we absolutely have to do it for fixed-point, since the end-points
19158 -- of the range and the size are determined by the small value, which
19159 -- could be reset before the freeze point.
19161 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
19162 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
19164 -- Complete definition of first subtype. The inheritance of the rep item
19165 -- chain ensures that SPARK-related pragmas are not clobbered when the
19166 -- ordinary fixed point type acts as a full view of a private type.
19168 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
19169 Set_Etype (T, Implicit_Base);
19170 Init_Size_Align (T);
19171 Inherit_Rep_Item_Chain (T, Implicit_Base);
19172 Set_Small_Value (T, Small_Val);
19173 Set_Delta_Value (T, Delta_Val);
19174 Set_Is_Constrained (T);
19175 end Ordinary_Fixed_Point_Type_Declaration;
19177 ----------------------------------
19178 -- Preanalyze_Assert_Expression --
19179 ----------------------------------
19181 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19183 In_Assertion_Expr := In_Assertion_Expr + 1;
19184 Preanalyze_Spec_Expression (N, T);
19185 In_Assertion_Expr := In_Assertion_Expr - 1;
19186 end Preanalyze_Assert_Expression;
19188 -----------------------------------
19189 -- Preanalyze_Default_Expression --
19190 -----------------------------------
19192 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
19193 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
19195 In_Default_Expr := True;
19196 Preanalyze_Spec_Expression (N, T);
19197 In_Default_Expr := Save_In_Default_Expr;
19198 end Preanalyze_Default_Expression;
19200 --------------------------------
19201 -- Preanalyze_Spec_Expression --
19202 --------------------------------
19204 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19205 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19207 In_Spec_Expression := True;
19208 Preanalyze_And_Resolve (N, T);
19209 In_Spec_Expression := Save_In_Spec_Expression;
19210 end Preanalyze_Spec_Expression;
19212 ----------------------------------------
19213 -- Prepare_Private_Subtype_Completion --
19214 ----------------------------------------
19216 procedure Prepare_Private_Subtype_Completion
19218 Related_Nod : Node_Id)
19220 Id_B : constant Entity_Id := Base_Type (Id);
19221 Full_B : Entity_Id := Full_View (Id_B);
19225 if Present (Full_B) then
19227 -- Get to the underlying full view if necessary
19229 if Is_Private_Type (Full_B)
19230 and then Present (Underlying_Full_View (Full_B))
19232 Full_B := Underlying_Full_View (Full_B);
19235 -- The Base_Type is already completed, we can complete the subtype
19236 -- now. We have to create a new entity with the same name, Thus we
19237 -- can't use Create_Itype.
19239 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
19240 Set_Is_Itype (Full);
19241 Set_Associated_Node_For_Itype (Full, Related_Nod);
19242 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
19245 -- The parent subtype may be private, but the base might not, in some
19246 -- nested instances. In that case, the subtype does not need to be
19247 -- exchanged. It would still be nice to make private subtypes and their
19248 -- bases consistent at all times ???
19250 if Is_Private_Type (Id_B) then
19251 Append_Elmt (Id, Private_Dependents (Id_B));
19253 end Prepare_Private_Subtype_Completion;
19255 ---------------------------
19256 -- Process_Discriminants --
19257 ---------------------------
19259 procedure Process_Discriminants
19261 Prev : Entity_Id := Empty)
19263 Elist : constant Elist_Id := New_Elmt_List;
19266 Discr_Number : Uint;
19267 Discr_Type : Entity_Id;
19268 Default_Present : Boolean := False;
19269 Default_Not_Present : Boolean := False;
19272 -- A composite type other than an array type can have discriminants.
19273 -- On entry, the current scope is the composite type.
19275 -- The discriminants are initially entered into the scope of the type
19276 -- via Enter_Name with the default Ekind of E_Void to prevent premature
19277 -- use, as explained at the end of this procedure.
19279 Discr := First (Discriminant_Specifications (N));
19280 while Present (Discr) loop
19281 Enter_Name (Defining_Identifier (Discr));
19283 -- For navigation purposes we add a reference to the discriminant
19284 -- in the entity for the type. If the current declaration is a
19285 -- completion, place references on the partial view. Otherwise the
19286 -- type is the current scope.
19288 if Present (Prev) then
19290 -- The references go on the partial view, if present. If the
19291 -- partial view has discriminants, the references have been
19292 -- generated already.
19294 if not Has_Discriminants (Prev) then
19295 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
19299 (Current_Scope, Defining_Identifier (Discr), 'd');
19302 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
19303 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
19305 -- Ada 2005 (AI-254)
19307 if Present (Access_To_Subprogram_Definition
19308 (Discriminant_Type (Discr)))
19309 and then Protected_Present (Access_To_Subprogram_Definition
19310 (Discriminant_Type (Discr)))
19313 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
19317 Find_Type (Discriminant_Type (Discr));
19318 Discr_Type := Etype (Discriminant_Type (Discr));
19320 if Error_Posted (Discriminant_Type (Discr)) then
19321 Discr_Type := Any_Type;
19325 -- Handling of discriminants that are access types
19327 if Is_Access_Type (Discr_Type) then
19329 -- Ada 2005 (AI-230): Access discriminant allowed in non-
19330 -- limited record types
19332 if Ada_Version < Ada_2005 then
19333 Check_Access_Discriminant_Requires_Limited
19334 (Discr, Discriminant_Type (Discr));
19337 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
19339 ("(Ada 83) access discriminant not allowed", Discr);
19342 -- If not access type, must be a discrete type
19344 elsif not Is_Discrete_Type (Discr_Type) then
19346 ("discriminants must have a discrete or access type",
19347 Discriminant_Type (Discr));
19350 Set_Etype (Defining_Identifier (Discr), Discr_Type);
19352 -- If a discriminant specification includes the assignment compound
19353 -- delimiter followed by an expression, the expression is the default
19354 -- expression of the discriminant; the default expression must be of
19355 -- the type of the discriminant. (RM 3.7.1) Since this expression is
19356 -- a default expression, we do the special preanalysis, since this
19357 -- expression does not freeze (see section "Handling of Default and
19358 -- Per-Object Expressions" in spec of package Sem).
19360 if Present (Expression (Discr)) then
19361 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
19365 if Nkind (N) = N_Formal_Type_Declaration then
19367 ("discriminant defaults not allowed for formal type",
19368 Expression (Discr));
19370 -- Flag an error for a tagged type with defaulted discriminants,
19371 -- excluding limited tagged types when compiling for Ada 2012
19372 -- (see AI05-0214).
19374 elsif Is_Tagged_Type (Current_Scope)
19375 and then (not Is_Limited_Type (Current_Scope)
19376 or else Ada_Version < Ada_2012)
19377 and then Comes_From_Source (N)
19379 -- Note: see similar test in Check_Or_Process_Discriminants, to
19380 -- handle the (illegal) case of the completion of an untagged
19381 -- view with discriminants with defaults by a tagged full view.
19382 -- We skip the check if Discr does not come from source, to
19383 -- account for the case of an untagged derived type providing
19384 -- defaults for a renamed discriminant from a private untagged
19385 -- ancestor with a tagged full view (ACATS B460006).
19387 if Ada_Version >= Ada_2012 then
19389 ("discriminants of nonlimited tagged type cannot have"
19391 Expression (Discr));
19394 ("discriminants of tagged type cannot have defaults",
19395 Expression (Discr));
19399 Default_Present := True;
19400 Append_Elmt (Expression (Discr), Elist);
19402 -- Tag the defining identifiers for the discriminants with
19403 -- their corresponding default expressions from the tree.
19405 Set_Discriminant_Default_Value
19406 (Defining_Identifier (Discr), Expression (Discr));
19409 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19410 -- gets set unless we can be sure that no range check is required.
19412 if (GNATprove_Mode or not Expander_Active)
19415 (Expression (Discr), Discr_Type, Assume_Valid => True)
19417 Set_Do_Range_Check (Expression (Discr));
19420 -- No default discriminant value given
19423 Default_Not_Present := True;
19426 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19427 -- Discr_Type but with the null-exclusion attribute
19429 if Ada_Version >= Ada_2005 then
19431 -- Ada 2005 (AI-231): Static checks
19433 if Can_Never_Be_Null (Discr_Type) then
19434 Null_Exclusion_Static_Checks (Discr);
19436 elsif Is_Access_Type (Discr_Type)
19437 and then Null_Exclusion_Present (Discr)
19439 -- No need to check itypes because in their case this check
19440 -- was done at their point of creation
19442 and then not Is_Itype (Discr_Type)
19444 if Can_Never_Be_Null (Discr_Type) then
19446 ("`NOT NULL` not allowed (& already excludes null)",
19451 Set_Etype (Defining_Identifier (Discr),
19452 Create_Null_Excluding_Itype
19454 Related_Nod => Discr));
19456 -- Check for improper null exclusion if the type is otherwise
19457 -- legal for a discriminant.
19459 elsif Null_Exclusion_Present (Discr)
19460 and then Is_Discrete_Type (Discr_Type)
19463 ("null exclusion can only apply to an access type", Discr);
19466 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19467 -- can't have defaults. Synchronized types, or types that are
19468 -- explicitly limited are fine, but special tests apply to derived
19469 -- types in generics: in a generic body we have to assume the
19470 -- worst, and therefore defaults are not allowed if the parent is
19471 -- a generic formal private type (see ACATS B370001).
19473 if Is_Access_Type (Discr_Type) and then Default_Present then
19474 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19475 or else Is_Limited_Record (Current_Scope)
19476 or else Is_Concurrent_Type (Current_Scope)
19477 or else Is_Concurrent_Record_Type (Current_Scope)
19478 or else Ekind (Current_Scope) = E_Limited_Private_Type
19480 if not Is_Derived_Type (Current_Scope)
19481 or else not Is_Generic_Type (Etype (Current_Scope))
19482 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19483 or else Limited_Present
19484 (Type_Definition (Parent (Current_Scope)))
19490 ("access discriminants of nonlimited types cannot "
19491 & "have defaults", Expression (Discr));
19494 elsif Present (Expression (Discr)) then
19496 ("(Ada 2005) access discriminants of nonlimited types "
19497 & "cannot have defaults", Expression (Discr));
19502 -- A discriminant cannot be effectively volatile (SPARK RM 7.1.3(6)).
19503 -- This check is relevant only when SPARK_Mode is on as it is not a
19504 -- standard Ada legality rule.
19507 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19509 Error_Msg_N ("discriminant cannot be volatile", Discr);
19515 -- An element list consisting of the default expressions of the
19516 -- discriminants is constructed in the above loop and used to set
19517 -- the Discriminant_Constraint attribute for the type. If an object
19518 -- is declared of this (record or task) type without any explicit
19519 -- discriminant constraint given, this element list will form the
19520 -- actual parameters for the corresponding initialization procedure
19523 Set_Discriminant_Constraint (Current_Scope, Elist);
19524 Set_Stored_Constraint (Current_Scope, No_Elist);
19526 -- Default expressions must be provided either for all or for none
19527 -- of the discriminants of a discriminant part. (RM 3.7.1)
19529 if Default_Present and then Default_Not_Present then
19531 ("incomplete specification of defaults for discriminants", N);
19534 -- The use of the name of a discriminant is not allowed in default
19535 -- expressions of a discriminant part if the specification of the
19536 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19538 -- To detect this, the discriminant names are entered initially with an
19539 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19540 -- attempt to use a void entity (for example in an expression that is
19541 -- type-checked) produces the error message: premature usage. Now after
19542 -- completing the semantic analysis of the discriminant part, we can set
19543 -- the Ekind of all the discriminants appropriately.
19545 Discr := First (Discriminant_Specifications (N));
19546 Discr_Number := Uint_1;
19547 while Present (Discr) loop
19548 Id := Defining_Identifier (Discr);
19549 Set_Ekind (Id, E_Discriminant);
19550 Init_Component_Location (Id);
19552 Set_Discriminant_Number (Id, Discr_Number);
19554 -- Make sure this is always set, even in illegal programs
19556 Set_Corresponding_Discriminant (Id, Empty);
19558 -- Initialize the Original_Record_Component to the entity itself.
19559 -- Inherit_Components will propagate the right value to
19560 -- discriminants in derived record types.
19562 Set_Original_Record_Component (Id, Id);
19564 -- Create the discriminal for the discriminant
19566 Build_Discriminal (Id);
19569 Discr_Number := Discr_Number + 1;
19572 Set_Has_Discriminants (Current_Scope);
19573 end Process_Discriminants;
19575 -----------------------
19576 -- Process_Full_View --
19577 -----------------------
19579 -- WARNING: This routine manages Ghost regions. Return statements must be
19580 -- replaced by gotos which jump to the end of the routine and restore the
19583 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19584 procedure Collect_Implemented_Interfaces
19586 Ifaces : Elist_Id);
19587 -- Ada 2005: Gather all the interfaces that Typ directly or
19588 -- inherently implements. Duplicate entries are not added to
19589 -- the list Ifaces.
19591 ------------------------------------
19592 -- Collect_Implemented_Interfaces --
19593 ------------------------------------
19595 procedure Collect_Implemented_Interfaces
19600 Iface_Elmt : Elmt_Id;
19603 -- Abstract interfaces are only associated with tagged record types
19605 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19609 -- Recursively climb to the ancestors
19611 if Etype (Typ) /= Typ
19613 -- Protect the frontend against wrong cyclic declarations like:
19615 -- type B is new A with private;
19616 -- type C is new A with private;
19618 -- type B is new C with null record;
19619 -- type C is new B with null record;
19621 and then Etype (Typ) /= Priv_T
19622 and then Etype (Typ) /= Full_T
19624 -- Keep separate the management of private type declarations
19626 if Ekind (Typ) = E_Record_Type_With_Private then
19628 -- Handle the following illegal usage:
19629 -- type Private_Type is tagged private;
19631 -- type Private_Type is new Type_Implementing_Iface;
19633 if Present (Full_View (Typ))
19634 and then Etype (Typ) /= Full_View (Typ)
19636 if Is_Interface (Etype (Typ)) then
19637 Append_Unique_Elmt (Etype (Typ), Ifaces);
19640 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19643 -- Non-private types
19646 if Is_Interface (Etype (Typ)) then
19647 Append_Unique_Elmt (Etype (Typ), Ifaces);
19650 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19654 -- Handle entities in the list of abstract interfaces
19656 if Present (Interfaces (Typ)) then
19657 Iface_Elmt := First_Elmt (Interfaces (Typ));
19658 while Present (Iface_Elmt) loop
19659 Iface := Node (Iface_Elmt);
19661 pragma Assert (Is_Interface (Iface));
19663 if not Contain_Interface (Iface, Ifaces) then
19664 Append_Elmt (Iface, Ifaces);
19665 Collect_Implemented_Interfaces (Iface, Ifaces);
19668 Next_Elmt (Iface_Elmt);
19671 end Collect_Implemented_Interfaces;
19675 Full_Indic : Node_Id;
19676 Full_Parent : Entity_Id;
19677 Mode : Ghost_Mode_Type;
19678 Priv_Parent : Entity_Id;
19680 -- Start of processing for Process_Full_View
19683 Mark_And_Set_Ghost_Completion (N, Priv_T, Mode);
19685 -- First some sanity checks that must be done after semantic
19686 -- decoration of the full view and thus cannot be placed with other
19687 -- similar checks in Find_Type_Name
19689 if not Is_Limited_Type (Priv_T)
19690 and then (Is_Limited_Type (Full_T)
19691 or else Is_Limited_Composite (Full_T))
19693 if In_Instance then
19697 ("completion of nonlimited type cannot be limited", Full_T);
19698 Explain_Limited_Type (Full_T, Full_T);
19701 elsif Is_Abstract_Type (Full_T)
19702 and then not Is_Abstract_Type (Priv_T)
19705 ("completion of nonabstract type cannot be abstract", Full_T);
19707 elsif Is_Tagged_Type (Priv_T)
19708 and then Is_Limited_Type (Priv_T)
19709 and then not Is_Limited_Type (Full_T)
19711 -- If pragma CPP_Class was applied to the private declaration
19712 -- propagate the limitedness to the full-view
19714 if Is_CPP_Class (Priv_T) then
19715 Set_Is_Limited_Record (Full_T);
19717 -- GNAT allow its own definition of Limited_Controlled to disobey
19718 -- this rule in order in ease the implementation. This test is safe
19719 -- because Root_Controlled is defined in a child of System that
19720 -- normal programs are not supposed to use.
19722 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19723 Set_Is_Limited_Composite (Full_T);
19726 ("completion of limited tagged type must be limited", Full_T);
19729 elsif Is_Generic_Type (Priv_T) then
19730 Error_Msg_N ("generic type cannot have a completion", Full_T);
19733 -- Check that ancestor interfaces of private and full views are
19734 -- consistent. We omit this check for synchronized types because
19735 -- they are performed on the corresponding record type when frozen.
19737 if Ada_Version >= Ada_2005
19738 and then Is_Tagged_Type (Priv_T)
19739 and then Is_Tagged_Type (Full_T)
19740 and then not Is_Concurrent_Type (Full_T)
19744 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19745 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19748 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19749 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19751 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19752 -- an interface type if and only if the full type is descendant
19753 -- of the interface type (AARM 7.3 (7.3/2)).
19755 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19757 if Present (Iface) then
19759 ("interface in partial view& not implemented by full type "
19760 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19763 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19765 if Present (Iface) then
19767 ("interface & not implemented by partial view "
19768 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19773 if Is_Tagged_Type (Priv_T)
19774 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19775 and then Is_Derived_Type (Full_T)
19777 Priv_Parent := Etype (Priv_T);
19779 -- The full view of a private extension may have been transformed
19780 -- into an unconstrained derived type declaration and a subtype
19781 -- declaration (see build_derived_record_type for details).
19783 if Nkind (N) = N_Subtype_Declaration then
19784 Full_Indic := Subtype_Indication (N);
19785 Full_Parent := Etype (Base_Type (Full_T));
19787 Full_Indic := Subtype_Indication (Type_Definition (N));
19788 Full_Parent := Etype (Full_T);
19791 -- Check that the parent type of the full type is a descendant of
19792 -- the ancestor subtype given in the private extension. If either
19793 -- entity has an Etype equal to Any_Type then we had some previous
19794 -- error situation [7.3(8)].
19796 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19799 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19800 -- any order. Therefore we don't have to check that its parent must
19801 -- be a descendant of the parent of the private type declaration.
19803 elsif Is_Interface (Priv_Parent)
19804 and then Is_Interface (Full_Parent)
19808 -- Ada 2005 (AI-251): If the parent of the private type declaration
19809 -- is an interface there is no need to check that it is an ancestor
19810 -- of the associated full type declaration. The required tests for
19811 -- this case are performed by Build_Derived_Record_Type.
19813 elsif not Is_Interface (Base_Type (Priv_Parent))
19814 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19817 ("parent of full type must descend from parent of private "
19818 & "extension", Full_Indic);
19820 -- First check a formal restriction, and then proceed with checking
19821 -- Ada rules. Since the formal restriction is not a serious error, we
19822 -- don't prevent further error detection for this check, hence the
19826 -- In formal mode, when completing a private extension the type
19827 -- named in the private part must be exactly the same as that
19828 -- named in the visible part.
19830 if Priv_Parent /= Full_Parent then
19831 Error_Msg_Name_1 := Chars (Priv_Parent);
19832 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19835 -- Check the rules of 7.3(10): if the private extension inherits
19836 -- known discriminants, then the full type must also inherit those
19837 -- discriminants from the same (ancestor) type, and the parent
19838 -- subtype of the full type must be constrained if and only if
19839 -- the ancestor subtype of the private extension is constrained.
19841 if No (Discriminant_Specifications (Parent (Priv_T)))
19842 and then not Has_Unknown_Discriminants (Priv_T)
19843 and then Has_Discriminants (Base_Type (Priv_Parent))
19846 Priv_Indic : constant Node_Id :=
19847 Subtype_Indication (Parent (Priv_T));
19849 Priv_Constr : constant Boolean :=
19850 Is_Constrained (Priv_Parent)
19852 Nkind (Priv_Indic) = N_Subtype_Indication
19854 Is_Constrained (Entity (Priv_Indic));
19856 Full_Constr : constant Boolean :=
19857 Is_Constrained (Full_Parent)
19859 Nkind (Full_Indic) = N_Subtype_Indication
19861 Is_Constrained (Entity (Full_Indic));
19863 Priv_Discr : Entity_Id;
19864 Full_Discr : Entity_Id;
19867 Priv_Discr := First_Discriminant (Priv_Parent);
19868 Full_Discr := First_Discriminant (Full_Parent);
19869 while Present (Priv_Discr) and then Present (Full_Discr) loop
19870 if Original_Record_Component (Priv_Discr) =
19871 Original_Record_Component (Full_Discr)
19873 Corresponding_Discriminant (Priv_Discr) =
19874 Corresponding_Discriminant (Full_Discr)
19881 Next_Discriminant (Priv_Discr);
19882 Next_Discriminant (Full_Discr);
19885 if Present (Priv_Discr) or else Present (Full_Discr) then
19887 ("full view must inherit discriminants of the parent "
19888 & "type used in the private extension", Full_Indic);
19890 elsif Priv_Constr and then not Full_Constr then
19892 ("parent subtype of full type must be constrained",
19895 elsif Full_Constr and then not Priv_Constr then
19897 ("parent subtype of full type must be unconstrained",
19902 -- Check the rules of 7.3(12): if a partial view has neither
19903 -- known or unknown discriminants, then the full type
19904 -- declaration shall define a definite subtype.
19906 elsif not Has_Unknown_Discriminants (Priv_T)
19907 and then not Has_Discriminants (Priv_T)
19908 and then not Is_Constrained (Full_T)
19911 ("full view must define a constrained type if partial view "
19912 & "has no discriminants", Full_T);
19915 -- ??????? Do we implement the following properly ?????
19916 -- If the ancestor subtype of a private extension has constrained
19917 -- discriminants, then the parent subtype of the full view shall
19918 -- impose a statically matching constraint on those discriminants
19923 -- For untagged types, verify that a type without discriminants is
19924 -- not completed with an unconstrained type. A separate error message
19925 -- is produced if the full type has defaulted discriminants.
19927 if Is_Definite_Subtype (Priv_T)
19928 and then not Is_Definite_Subtype (Full_T)
19930 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19932 ("full view of& not compatible with declaration#",
19935 if not Is_Tagged_Type (Full_T) then
19937 ("\one is constrained, the other unconstrained", Full_T);
19942 -- AI-419: verify that the use of "limited" is consistent
19945 Orig_Decl : constant Node_Id := Original_Node (N);
19948 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19949 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19951 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19953 if not Limited_Present (Parent (Priv_T))
19954 and then not Synchronized_Present (Parent (Priv_T))
19955 and then Limited_Present (Type_Definition (Orig_Decl))
19958 ("full view of non-limited extension cannot be limited", N);
19960 -- Conversely, if the partial view carries the limited keyword,
19961 -- the full view must as well, even if it may be redundant.
19963 elsif Limited_Present (Parent (Priv_T))
19964 and then not Limited_Present (Type_Definition (Orig_Decl))
19967 ("full view of limited extension must be explicitly limited",
19973 -- Ada 2005 (AI-443): A synchronized private extension must be
19974 -- completed by a task or protected type.
19976 if Ada_Version >= Ada_2005
19977 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19978 and then Synchronized_Present (Parent (Priv_T))
19979 and then not Is_Concurrent_Type (Full_T)
19981 Error_Msg_N ("full view of synchronized extension must " &
19982 "be synchronized type", N);
19985 -- Ada 2005 AI-363: if the full view has discriminants with
19986 -- defaults, it is illegal to declare constrained access subtypes
19987 -- whose designated type is the current type. This allows objects
19988 -- of the type that are declared in the heap to be unconstrained.
19990 if not Has_Unknown_Discriminants (Priv_T)
19991 and then not Has_Discriminants (Priv_T)
19992 and then Has_Discriminants (Full_T)
19994 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19996 Set_Has_Constrained_Partial_View (Full_T);
19997 Set_Has_Constrained_Partial_View (Priv_T);
20000 -- Create a full declaration for all its subtypes recorded in
20001 -- Private_Dependents and swap them similarly to the base type. These
20002 -- are subtypes that have been define before the full declaration of
20003 -- the private type. We also swap the entry in Private_Dependents list
20004 -- so we can properly restore the private view on exit from the scope.
20007 Priv_Elmt : Elmt_Id;
20008 Priv_Scop : Entity_Id;
20013 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
20014 while Present (Priv_Elmt) loop
20015 Priv := Node (Priv_Elmt);
20016 Priv_Scop := Scope (Priv);
20018 if Ekind_In (Priv, E_Private_Subtype,
20019 E_Limited_Private_Subtype,
20020 E_Record_Subtype_With_Private)
20022 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
20023 Set_Is_Itype (Full);
20024 Set_Parent (Full, Parent (Priv));
20025 Set_Associated_Node_For_Itype (Full, N);
20027 -- Now we need to complete the private subtype, but since the
20028 -- base type has already been swapped, we must also swap the
20029 -- subtypes (and thus, reverse the arguments in the call to
20030 -- Complete_Private_Subtype). Also note that we may need to
20031 -- re-establish the scope of the private subtype.
20033 Copy_And_Swap (Priv, Full);
20035 if not In_Open_Scopes (Priv_Scop) then
20036 Push_Scope (Priv_Scop);
20039 -- Reset Priv_Scop to Empty to indicate no scope was pushed
20041 Priv_Scop := Empty;
20044 Complete_Private_Subtype (Full, Priv, Full_T, N);
20046 if Present (Priv_Scop) then
20050 Replace_Elmt (Priv_Elmt, Full);
20053 Next_Elmt (Priv_Elmt);
20057 -- If the private view was tagged, copy the new primitive operations
20058 -- from the private view to the full view.
20060 if Is_Tagged_Type (Full_T) then
20062 Disp_Typ : Entity_Id;
20063 Full_List : Elist_Id;
20065 Prim_Elmt : Elmt_Id;
20066 Priv_List : Elist_Id;
20070 L : Elist_Id) return Boolean;
20071 -- Determine whether list L contains element E
20079 L : Elist_Id) return Boolean
20081 List_Elmt : Elmt_Id;
20084 List_Elmt := First_Elmt (L);
20085 while Present (List_Elmt) loop
20086 if Node (List_Elmt) = E then
20090 Next_Elmt (List_Elmt);
20096 -- Start of processing
20099 if Is_Tagged_Type (Priv_T) then
20100 Priv_List := Primitive_Operations (Priv_T);
20101 Prim_Elmt := First_Elmt (Priv_List);
20103 -- In the case of a concurrent type completing a private tagged
20104 -- type, primitives may have been declared in between the two
20105 -- views. These subprograms need to be wrapped the same way
20106 -- entries and protected procedures are handled because they
20107 -- cannot be directly shared by the two views.
20109 if Is_Concurrent_Type (Full_T) then
20111 Conc_Typ : constant Entity_Id :=
20112 Corresponding_Record_Type (Full_T);
20113 Curr_Nod : Node_Id := Parent (Conc_Typ);
20114 Wrap_Spec : Node_Id;
20117 while Present (Prim_Elmt) loop
20118 Prim := Node (Prim_Elmt);
20120 if Comes_From_Source (Prim)
20121 and then not Is_Abstract_Subprogram (Prim)
20124 Make_Subprogram_Declaration (Sloc (Prim),
20128 Obj_Typ => Conc_Typ,
20130 Parameter_Specifications
20133 Insert_After (Curr_Nod, Wrap_Spec);
20134 Curr_Nod := Wrap_Spec;
20136 Analyze (Wrap_Spec);
20138 -- Remove the wrapper from visibility to avoid
20139 -- spurious conflict with the wrapped entity.
20141 Set_Is_Immediately_Visible
20142 (Defining_Entity (Specification (Wrap_Spec)),
20146 Next_Elmt (Prim_Elmt);
20152 -- For non-concurrent types, transfer explicit primitives, but
20153 -- omit those inherited from the parent of the private view
20154 -- since they will be re-inherited later on.
20157 Full_List := Primitive_Operations (Full_T);
20159 while Present (Prim_Elmt) loop
20160 Prim := Node (Prim_Elmt);
20162 if Comes_From_Source (Prim)
20163 and then not Contains (Prim, Full_List)
20165 Append_Elmt (Prim, Full_List);
20168 Next_Elmt (Prim_Elmt);
20172 -- Untagged private view
20175 Full_List := Primitive_Operations (Full_T);
20177 -- In this case the partial view is untagged, so here we locate
20178 -- all of the earlier primitives that need to be treated as
20179 -- dispatching (those that appear between the two views). Note
20180 -- that these additional operations must all be new operations
20181 -- (any earlier operations that override inherited operations
20182 -- of the full view will already have been inserted in the
20183 -- primitives list, marked by Check_Operation_From_Private_View
20184 -- as dispatching. Note that implicit "/=" operators are
20185 -- excluded from being added to the primitives list since they
20186 -- shouldn't be treated as dispatching (tagged "/=" is handled
20189 Prim := Next_Entity (Full_T);
20190 while Present (Prim) and then Prim /= Priv_T loop
20191 if Ekind_In (Prim, E_Procedure, E_Function) then
20192 Disp_Typ := Find_Dispatching_Type (Prim);
20194 if Disp_Typ = Full_T
20195 and then (Chars (Prim) /= Name_Op_Ne
20196 or else Comes_From_Source (Prim))
20198 Check_Controlling_Formals (Full_T, Prim);
20200 if not Is_Dispatching_Operation (Prim) then
20201 Append_Elmt (Prim, Full_List);
20202 Set_Is_Dispatching_Operation (Prim, True);
20203 Set_DT_Position_Value (Prim, No_Uint);
20206 elsif Is_Dispatching_Operation (Prim)
20207 and then Disp_Typ /= Full_T
20210 -- Verify that it is not otherwise controlled by a
20211 -- formal or a return value of type T.
20213 Check_Controlling_Formals (Disp_Typ, Prim);
20217 Next_Entity (Prim);
20221 -- For the tagged case, the two views can share the same primitive
20222 -- operations list and the same class-wide type. Update attributes
20223 -- of the class-wide type which depend on the full declaration.
20225 if Is_Tagged_Type (Priv_T) then
20226 Set_Direct_Primitive_Operations (Priv_T, Full_List);
20227 Set_Class_Wide_Type
20228 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
20230 Propagate_Concurrent_Flags (Class_Wide_Type (Priv_T), Full_T);
20235 -- Ada 2005 AI 161: Check preelaborable initialization consistency
20237 if Known_To_Have_Preelab_Init (Priv_T) then
20239 -- Case where there is a pragma Preelaborable_Initialization. We
20240 -- always allow this in predefined units, which is cheating a bit,
20241 -- but it means we don't have to struggle to meet the requirements in
20242 -- the RM for having Preelaborable Initialization. Otherwise we
20243 -- require that the type meets the RM rules. But we can't check that
20244 -- yet, because of the rule about overriding Initialize, so we simply
20245 -- set a flag that will be checked at freeze time.
20247 if not In_Predefined_Unit (Full_T) then
20248 Set_Must_Have_Preelab_Init (Full_T);
20252 -- If pragma CPP_Class was applied to the private type declaration,
20253 -- propagate it now to the full type declaration.
20255 if Is_CPP_Class (Priv_T) then
20256 Set_Is_CPP_Class (Full_T);
20257 Set_Convention (Full_T, Convention_CPP);
20259 -- Check that components of imported CPP types do not have default
20262 Check_CPP_Type_Has_No_Defaults (Full_T);
20265 -- If the private view has user specified stream attributes, then so has
20268 -- Why the test, how could these flags be already set in Full_T ???
20270 if Has_Specified_Stream_Read (Priv_T) then
20271 Set_Has_Specified_Stream_Read (Full_T);
20274 if Has_Specified_Stream_Write (Priv_T) then
20275 Set_Has_Specified_Stream_Write (Full_T);
20278 if Has_Specified_Stream_Input (Priv_T) then
20279 Set_Has_Specified_Stream_Input (Full_T);
20282 if Has_Specified_Stream_Output (Priv_T) then
20283 Set_Has_Specified_Stream_Output (Full_T);
20286 -- Propagate Default_Initial_Condition-related attributes from the
20287 -- partial view to the full view and its base type.
20289 Propagate_DIC_Attributes (Full_T, From_Typ => Priv_T);
20290 Propagate_DIC_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20292 -- Propagate invariant-related attributes from the partial view to the
20293 -- full view and its base type.
20295 Propagate_Invariant_Attributes (Full_T, From_Typ => Priv_T);
20296 Propagate_Invariant_Attributes (Base_Type (Full_T), From_Typ => Priv_T);
20298 -- AI12-0041: Detect an attempt to inherit a class-wide type invariant
20299 -- in the full view without advertising the inheritance in the partial
20300 -- view. This can only occur when the partial view has no parent type
20301 -- and the full view has an interface as a parent. Any other scenarios
20302 -- are illegal because implemented interfaces must match between the
20305 if Is_Tagged_Type (Priv_T) and then Is_Tagged_Type (Full_T) then
20307 Full_Par : constant Entity_Id := Etype (Full_T);
20308 Priv_Par : constant Entity_Id := Etype (Priv_T);
20311 if not Is_Interface (Priv_Par)
20312 and then Is_Interface (Full_Par)
20313 and then Has_Inheritable_Invariants (Full_Par)
20316 ("hidden inheritance of class-wide type invariants not "
20322 -- Propagate predicates to full type, and predicate function if already
20323 -- defined. It is not clear that this can actually happen? the partial
20324 -- view cannot be frozen yet, and the predicate function has not been
20325 -- built. Still it is a cheap check and seems safer to make it.
20327 if Has_Predicates (Priv_T) then
20328 Set_Has_Predicates (Full_T);
20330 if Present (Predicate_Function (Priv_T)) then
20331 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
20336 Restore_Ghost_Mode (Mode);
20337 end Process_Full_View;
20339 -----------------------------------
20340 -- Process_Incomplete_Dependents --
20341 -----------------------------------
20343 procedure Process_Incomplete_Dependents
20345 Full_T : Entity_Id;
20348 Inc_Elmt : Elmt_Id;
20349 Priv_Dep : Entity_Id;
20350 New_Subt : Entity_Id;
20352 Disc_Constraint : Elist_Id;
20355 if No (Private_Dependents (Inc_T)) then
20359 -- Itypes that may be generated by the completion of an incomplete
20360 -- subtype are not used by the back-end and not attached to the tree.
20361 -- They are created only for constraint-checking purposes.
20363 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20364 while Present (Inc_Elmt) loop
20365 Priv_Dep := Node (Inc_Elmt);
20367 if Ekind (Priv_Dep) = E_Subprogram_Type then
20369 -- An Access_To_Subprogram type may have a return type or a
20370 -- parameter type that is incomplete. Replace with the full view.
20372 if Etype (Priv_Dep) = Inc_T then
20373 Set_Etype (Priv_Dep, Full_T);
20377 Formal : Entity_Id;
20380 Formal := First_Formal (Priv_Dep);
20381 while Present (Formal) loop
20382 if Etype (Formal) = Inc_T then
20383 Set_Etype (Formal, Full_T);
20386 Next_Formal (Formal);
20390 elsif Is_Overloadable (Priv_Dep) then
20392 -- If a subprogram in the incomplete dependents list is primitive
20393 -- for a tagged full type then mark it as a dispatching operation,
20394 -- check whether it overrides an inherited subprogram, and check
20395 -- restrictions on its controlling formals. Note that a protected
20396 -- operation is never dispatching: only its wrapper operation
20397 -- (which has convention Ada) is.
20399 if Is_Tagged_Type (Full_T)
20400 and then Is_Primitive (Priv_Dep)
20401 and then Convention (Priv_Dep) /= Convention_Protected
20403 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20404 Set_Is_Dispatching_Operation (Priv_Dep);
20405 Check_Controlling_Formals (Full_T, Priv_Dep);
20408 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20410 -- Can happen during processing of a body before the completion
20411 -- of a TA type. Ignore, because spec is also on dependent list.
20415 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20416 -- corresponding subtype of the full view.
20418 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20419 Set_Subtype_Indication
20420 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20421 Set_Etype (Priv_Dep, Full_T);
20422 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20423 Set_Analyzed (Parent (Priv_Dep), False);
20425 -- Reanalyze the declaration, suppressing the call to
20426 -- Enter_Name to avoid duplicate names.
20428 Analyze_Subtype_Declaration
20429 (N => Parent (Priv_Dep),
20432 -- Dependent is a subtype
20435 -- We build a new subtype indication using the full view of the
20436 -- incomplete parent. The discriminant constraints have been
20437 -- elaborated already at the point of the subtype declaration.
20439 New_Subt := Create_Itype (E_Void, N);
20441 if Has_Discriminants (Full_T) then
20442 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20444 Disc_Constraint := No_Elist;
20447 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20448 Set_Full_View (Priv_Dep, New_Subt);
20451 Next_Elmt (Inc_Elmt);
20453 end Process_Incomplete_Dependents;
20455 --------------------------------
20456 -- Process_Range_Expr_In_Decl --
20457 --------------------------------
20459 procedure Process_Range_Expr_In_Decl
20462 Subtyp : Entity_Id := Empty;
20463 Check_List : List_Id := Empty_List;
20464 R_Check_Off : Boolean := False;
20465 In_Iter_Schm : Boolean := False)
20468 R_Checks : Check_Result;
20469 Insert_Node : Node_Id;
20470 Def_Id : Entity_Id;
20473 Analyze_And_Resolve (R, Base_Type (T));
20475 if Nkind (R) = N_Range then
20477 -- In SPARK, all ranges should be static, with the exception of the
20478 -- discrete type definition of a loop parameter specification.
20480 if not In_Iter_Schm
20481 and then not Is_OK_Static_Range (R)
20483 Check_SPARK_05_Restriction ("range should be static", R);
20486 Lo := Low_Bound (R);
20487 Hi := High_Bound (R);
20489 -- Validity checks on the range of a quantified expression are
20490 -- delayed until the construct is transformed into a loop.
20492 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20493 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20497 -- We need to ensure validity of the bounds here, because if we
20498 -- go ahead and do the expansion, then the expanded code will get
20499 -- analyzed with range checks suppressed and we miss the check.
20501 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20502 -- the temporaries generated by routine Remove_Side_Effects by means
20503 -- of validity checks must use the same names. When a range appears
20504 -- in the parent of a generic, the range is processed with checks
20505 -- disabled as part of the generic context and with checks enabled
20506 -- for code generation purposes. This leads to link issues as the
20507 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20508 -- template sees the temporaries generated by Remove_Side_Effects.
20511 Validity_Check_Range (R, Subtyp);
20514 -- If there were errors in the declaration, try and patch up some
20515 -- common mistakes in the bounds. The cases handled are literals
20516 -- which are Integer where the expected type is Real and vice versa.
20517 -- These corrections allow the compilation process to proceed further
20518 -- along since some basic assumptions of the format of the bounds
20521 if Etype (R) = Any_Type then
20522 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20524 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20526 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20528 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20530 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20532 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20534 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20536 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20543 -- If the bounds of the range have been mistakenly given as string
20544 -- literals (perhaps in place of character literals), then an error
20545 -- has already been reported, but we rewrite the string literal as a
20546 -- bound of the range's type to avoid blowups in later processing
20547 -- that looks at static values.
20549 if Nkind (Lo) = N_String_Literal then
20551 Make_Attribute_Reference (Sloc (Lo),
20552 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20553 Attribute_Name => Name_First));
20554 Analyze_And_Resolve (Lo);
20557 if Nkind (Hi) = N_String_Literal then
20559 Make_Attribute_Reference (Sloc (Hi),
20560 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20561 Attribute_Name => Name_First));
20562 Analyze_And_Resolve (Hi);
20565 -- If bounds aren't scalar at this point then exit, avoiding
20566 -- problems with further processing of the range in this procedure.
20568 if not Is_Scalar_Type (Etype (Lo)) then
20572 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20573 -- then range of the base type. Here we check whether the bounds
20574 -- are in the range of the subtype itself. Note that if the bounds
20575 -- represent the null range the Constraint_Error exception should
20578 -- ??? The following code should be cleaned up as follows
20580 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20581 -- is done in the call to Range_Check (R, T); below
20583 -- 2. The use of R_Check_Off should be investigated and possibly
20584 -- removed, this would clean up things a bit.
20586 if Is_Null_Range (Lo, Hi) then
20590 -- Capture values of bounds and generate temporaries for them
20591 -- if needed, before applying checks, since checks may cause
20592 -- duplication of the expression without forcing evaluation.
20594 -- The forced evaluation removes side effects from expressions,
20595 -- which should occur also in GNATprove mode. Otherwise, we end up
20596 -- with unexpected insertions of actions at places where this is
20597 -- not supposed to occur, e.g. on default parameters of a call.
20599 if Expander_Active or GNATprove_Mode then
20601 -- Call Force_Evaluation to create declarations as needed to
20602 -- deal with side effects, and also create typ_FIRST/LAST
20603 -- entities for bounds if we have a subtype name.
20605 -- Note: we do this transformation even if expansion is not
20606 -- active if we are in GNATprove_Mode since the transformation
20607 -- is in general required to ensure that the resulting tree has
20608 -- proper Ada semantics.
20611 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20613 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20616 -- We use a flag here instead of suppressing checks on the type
20617 -- because the type we check against isn't necessarily the place
20618 -- where we put the check.
20620 if not R_Check_Off then
20621 R_Checks := Get_Range_Checks (R, T);
20623 -- Look up tree to find an appropriate insertion point. We
20624 -- can't just use insert_actions because later processing
20625 -- depends on the insertion node. Prior to Ada 2012 the
20626 -- insertion point could only be a declaration or a loop, but
20627 -- quantified expressions can appear within any context in an
20628 -- expression, and the insertion point can be any statement,
20629 -- pragma, or declaration.
20631 Insert_Node := Parent (R);
20632 while Present (Insert_Node) loop
20634 Nkind (Insert_Node) in N_Declaration
20637 (Insert_Node, N_Component_Declaration,
20638 N_Loop_Parameter_Specification,
20639 N_Function_Specification,
20640 N_Procedure_Specification);
20642 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20643 or else Nkind (Insert_Node) in
20644 N_Statement_Other_Than_Procedure_Call
20645 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20648 Insert_Node := Parent (Insert_Node);
20651 -- Why would Type_Decl not be present??? Without this test,
20652 -- short regression tests fail.
20654 if Present (Insert_Node) then
20656 -- Case of loop statement. Verify that the range is part
20657 -- of the subtype indication of the iteration scheme.
20659 if Nkind (Insert_Node) = N_Loop_Statement then
20664 Indic := Parent (R);
20665 while Present (Indic)
20666 and then Nkind (Indic) /= N_Subtype_Indication
20668 Indic := Parent (Indic);
20671 if Present (Indic) then
20672 Def_Id := Etype (Subtype_Mark (Indic));
20674 Insert_Range_Checks
20678 Sloc (Insert_Node),
20680 Do_Before => True);
20684 -- Insertion before a declaration. If the declaration
20685 -- includes discriminants, the list of applicable checks
20686 -- is given by the caller.
20688 elsif Nkind (Insert_Node) in N_Declaration then
20689 Def_Id := Defining_Identifier (Insert_Node);
20691 if (Ekind (Def_Id) = E_Record_Type
20692 and then Depends_On_Discriminant (R))
20694 (Ekind (Def_Id) = E_Protected_Type
20695 and then Has_Discriminants (Def_Id))
20697 Append_Range_Checks
20699 Check_List, Def_Id, Sloc (Insert_Node), R);
20702 Insert_Range_Checks
20704 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20708 -- Insertion before a statement. Range appears in the
20709 -- context of a quantified expression. Insertion will
20710 -- take place when expression is expanded.
20719 -- Case of other than an explicit N_Range node
20721 -- The forced evaluation removes side effects from expressions, which
20722 -- should occur also in GNATprove mode. Otherwise, we end up with
20723 -- unexpected insertions of actions at places where this is not
20724 -- supposed to occur, e.g. on default parameters of a call.
20726 elsif Expander_Active or GNATprove_Mode then
20727 Get_Index_Bounds (R, Lo, Hi);
20728 Force_Evaluation (Lo);
20729 Force_Evaluation (Hi);
20731 end Process_Range_Expr_In_Decl;
20733 --------------------------------------
20734 -- Process_Real_Range_Specification --
20735 --------------------------------------
20737 procedure Process_Real_Range_Specification (Def : Node_Id) is
20738 Spec : constant Node_Id := Real_Range_Specification (Def);
20741 Err : Boolean := False;
20743 procedure Analyze_Bound (N : Node_Id);
20744 -- Analyze and check one bound
20746 -------------------
20747 -- Analyze_Bound --
20748 -------------------
20750 procedure Analyze_Bound (N : Node_Id) is
20752 Analyze_And_Resolve (N, Any_Real);
20754 if not Is_OK_Static_Expression (N) then
20755 Flag_Non_Static_Expr
20756 ("bound in real type definition is not static!", N);
20761 -- Start of processing for Process_Real_Range_Specification
20764 if Present (Spec) then
20765 Lo := Low_Bound (Spec);
20766 Hi := High_Bound (Spec);
20767 Analyze_Bound (Lo);
20768 Analyze_Bound (Hi);
20770 -- If error, clear away junk range specification
20773 Set_Real_Range_Specification (Def, Empty);
20776 end Process_Real_Range_Specification;
20778 ---------------------
20779 -- Process_Subtype --
20780 ---------------------
20782 function Process_Subtype
20784 Related_Nod : Node_Id;
20785 Related_Id : Entity_Id := Empty;
20786 Suffix : Character := ' ') return Entity_Id
20789 Def_Id : Entity_Id;
20790 Error_Node : Node_Id;
20791 Full_View_Id : Entity_Id;
20792 Subtype_Mark_Id : Entity_Id;
20794 May_Have_Null_Exclusion : Boolean;
20796 procedure Check_Incomplete (T : Node_Id);
20797 -- Called to verify that an incomplete type is not used prematurely
20799 ----------------------
20800 -- Check_Incomplete --
20801 ----------------------
20803 procedure Check_Incomplete (T : Node_Id) is
20805 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20807 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20809 not (Ada_Version >= Ada_2005
20811 (Nkind (Parent (T)) = N_Subtype_Declaration
20812 or else (Nkind (Parent (T)) = N_Subtype_Indication
20813 and then Nkind (Parent (Parent (T))) =
20814 N_Subtype_Declaration)))
20816 Error_Msg_N ("invalid use of type before its full declaration", T);
20818 end Check_Incomplete;
20820 -- Start of processing for Process_Subtype
20823 -- Case of no constraints present
20825 if Nkind (S) /= N_Subtype_Indication then
20827 Check_Incomplete (S);
20830 -- Ada 2005 (AI-231): Static check
20832 if Ada_Version >= Ada_2005
20833 and then Present (P)
20834 and then Null_Exclusion_Present (P)
20835 and then Nkind (P) /= N_Access_To_Object_Definition
20836 and then not Is_Access_Type (Entity (S))
20838 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20841 -- The following is ugly, can't we have a range or even a flag???
20843 May_Have_Null_Exclusion :=
20844 Nkind_In (P, N_Access_Definition,
20845 N_Access_Function_Definition,
20846 N_Access_Procedure_Definition,
20847 N_Access_To_Object_Definition,
20849 N_Component_Definition)
20851 Nkind_In (P, N_Derived_Type_Definition,
20852 N_Discriminant_Specification,
20853 N_Formal_Object_Declaration,
20854 N_Object_Declaration,
20855 N_Object_Renaming_Declaration,
20856 N_Parameter_Specification,
20857 N_Subtype_Declaration);
20859 -- Create an Itype that is a duplicate of Entity (S) but with the
20860 -- null-exclusion attribute.
20862 if May_Have_Null_Exclusion
20863 and then Is_Access_Type (Entity (S))
20864 and then Null_Exclusion_Present (P)
20866 -- No need to check the case of an access to object definition.
20867 -- It is correct to define double not-null pointers.
20870 -- type Not_Null_Int_Ptr is not null access Integer;
20871 -- type Acc is not null access Not_Null_Int_Ptr;
20873 and then Nkind (P) /= N_Access_To_Object_Definition
20875 if Can_Never_Be_Null (Entity (S)) then
20876 case Nkind (Related_Nod) is
20877 when N_Full_Type_Declaration =>
20878 if Nkind (Type_Definition (Related_Nod))
20879 in N_Array_Type_Definition
20883 (Component_Definition
20884 (Type_Definition (Related_Nod)));
20887 Subtype_Indication (Type_Definition (Related_Nod));
20890 when N_Subtype_Declaration =>
20891 Error_Node := Subtype_Indication (Related_Nod);
20893 when N_Object_Declaration =>
20894 Error_Node := Object_Definition (Related_Nod);
20896 when N_Component_Declaration =>
20898 Subtype_Indication (Component_Definition (Related_Nod));
20900 when N_Allocator =>
20901 Error_Node := Expression (Related_Nod);
20904 pragma Assert (False);
20905 Error_Node := Related_Nod;
20909 ("`NOT NULL` not allowed (& already excludes null)",
20915 Create_Null_Excluding_Itype
20917 Related_Nod => P));
20918 Set_Entity (S, Etype (S));
20923 -- Case of constraint present, so that we have an N_Subtype_Indication
20924 -- node (this node is created only if constraints are present).
20927 Find_Type (Subtype_Mark (S));
20929 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20931 (Nkind (Parent (S)) = N_Subtype_Declaration
20932 and then Is_Itype (Defining_Identifier (Parent (S))))
20934 Check_Incomplete (Subtype_Mark (S));
20938 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20940 -- Explicit subtype declaration case
20942 if Nkind (P) = N_Subtype_Declaration then
20943 Def_Id := Defining_Identifier (P);
20945 -- Explicit derived type definition case
20947 elsif Nkind (P) = N_Derived_Type_Definition then
20948 Def_Id := Defining_Identifier (Parent (P));
20950 -- Implicit case, the Def_Id must be created as an implicit type.
20951 -- The one exception arises in the case of concurrent types, array
20952 -- and access types, where other subsidiary implicit types may be
20953 -- created and must appear before the main implicit type. In these
20954 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20955 -- has not yet been called to create Def_Id.
20958 if Is_Array_Type (Subtype_Mark_Id)
20959 or else Is_Concurrent_Type (Subtype_Mark_Id)
20960 or else Is_Access_Type (Subtype_Mark_Id)
20964 -- For the other cases, we create a new unattached Itype,
20965 -- and set the indication to ensure it gets attached later.
20969 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20973 -- If the kind of constraint is invalid for this kind of type,
20974 -- then give an error, and then pretend no constraint was given.
20976 if not Is_Valid_Constraint_Kind
20977 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20980 ("incorrect constraint for this kind of type", Constraint (S));
20982 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20984 -- Set Ekind of orphan itype, to prevent cascaded errors
20986 if Present (Def_Id) then
20987 Set_Ekind (Def_Id, Ekind (Any_Type));
20990 -- Make recursive call, having got rid of the bogus constraint
20992 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20995 -- Remaining processing depends on type. Select on Base_Type kind to
20996 -- ensure getting to the concrete type kind in the case of a private
20997 -- subtype (needed when only doing semantic analysis).
20999 case Ekind (Base_Type (Subtype_Mark_Id)) is
21000 when Access_Kind =>
21002 -- If this is a constraint on a class-wide type, discard it.
21003 -- There is currently no way to express a partial discriminant
21004 -- constraint on a type with unknown discriminants. This is
21005 -- a pathology that the ACATS wisely decides not to test.
21007 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
21008 if Comes_From_Source (S) then
21010 ("constraint on class-wide type ignored??",
21014 if Nkind (P) = N_Subtype_Declaration then
21015 Set_Subtype_Indication (P,
21016 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
21019 return Subtype_Mark_Id;
21022 Constrain_Access (Def_Id, S, Related_Nod);
21025 and then Is_Itype (Designated_Type (Def_Id))
21026 and then Nkind (Related_Nod) = N_Subtype_Declaration
21027 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
21029 Build_Itype_Reference
21030 (Designated_Type (Def_Id), Related_Nod);
21034 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
21036 when Decimal_Fixed_Point_Kind =>
21037 Constrain_Decimal (Def_Id, S);
21039 when Enumeration_Kind =>
21040 Constrain_Enumeration (Def_Id, S);
21041 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21043 when Ordinary_Fixed_Point_Kind =>
21044 Constrain_Ordinary_Fixed (Def_Id, S);
21047 Constrain_Float (Def_Id, S);
21049 when Integer_Kind =>
21050 Constrain_Integer (Def_Id, S);
21051 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
21053 when Class_Wide_Kind
21054 | E_Incomplete_Type
21058 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21060 if Ekind (Def_Id) = E_Incomplete_Type then
21061 Set_Private_Dependents (Def_Id, New_Elmt_List);
21064 when Private_Kind =>
21065 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
21067 -- The base type may be private but Def_Id may be a full view
21070 if Is_Private_Type (Def_Id) then
21071 Set_Private_Dependents (Def_Id, New_Elmt_List);
21074 -- In case of an invalid constraint prevent further processing
21075 -- since the type constructed is missing expected fields.
21077 if Etype (Def_Id) = Any_Type then
21081 -- If the full view is that of a task with discriminants,
21082 -- we must constrain both the concurrent type and its
21083 -- corresponding record type. Otherwise we will just propagate
21084 -- the constraint to the full view, if available.
21086 if Present (Full_View (Subtype_Mark_Id))
21087 and then Has_Discriminants (Subtype_Mark_Id)
21088 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
21091 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
21093 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
21094 Constrain_Concurrent (Full_View_Id, S,
21095 Related_Nod, Related_Id, Suffix);
21096 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
21097 Set_Full_View (Def_Id, Full_View_Id);
21099 -- Introduce an explicit reference to the private subtype,
21100 -- to prevent scope anomalies in gigi if first use appears
21101 -- in a nested context, e.g. a later function body.
21102 -- Should this be generated in other contexts than a full
21103 -- type declaration?
21105 if Is_Itype (Def_Id)
21107 Nkind (Parent (P)) = N_Full_Type_Declaration
21109 Build_Itype_Reference (Def_Id, Parent (P));
21113 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
21116 when Concurrent_Kind =>
21117 Constrain_Concurrent (Def_Id, S,
21118 Related_Nod, Related_Id, Suffix);
21121 Error_Msg_N ("invalid subtype mark in subtype indication", S);
21124 -- Size and Convention are always inherited from the base type
21126 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
21127 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
21131 end Process_Subtype;
21133 -----------------------------
21134 -- Record_Type_Declaration --
21135 -----------------------------
21137 procedure Record_Type_Declaration
21142 Def : constant Node_Id := Type_Definition (N);
21143 Is_Tagged : Boolean;
21144 Tag_Comp : Entity_Id;
21147 -- These flags must be initialized before calling Process_Discriminants
21148 -- because this routine makes use of them.
21150 Set_Ekind (T, E_Record_Type);
21152 Init_Size_Align (T);
21153 Set_Interfaces (T, No_Elist);
21154 Set_Stored_Constraint (T, No_Elist);
21155 Set_Default_SSO (T);
21159 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
21160 if Limited_Present (Def) then
21161 Check_SPARK_05_Restriction ("limited is not allowed", N);
21164 if Abstract_Present (Def) then
21165 Check_SPARK_05_Restriction ("abstract is not allowed", N);
21168 -- The flag Is_Tagged_Type might have already been set by
21169 -- Find_Type_Name if it detected an error for declaration T. This
21170 -- arises in the case of private tagged types where the full view
21171 -- omits the word tagged.
21174 Tagged_Present (Def)
21175 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
21177 Set_Is_Limited_Record (T, Limited_Present (Def));
21180 Set_Is_Tagged_Type (T, True);
21181 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
21184 -- Type is abstract if full declaration carries keyword, or if
21185 -- previous partial view did.
21187 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
21188 or else Abstract_Present (Def));
21191 Check_SPARK_05_Restriction ("interface is not allowed", N);
21194 Analyze_Interface_Declaration (T, Def);
21196 if Present (Discriminant_Specifications (N)) then
21198 ("interface types cannot have discriminants",
21199 Defining_Identifier
21200 (First (Discriminant_Specifications (N))));
21204 -- First pass: if there are self-referential access components,
21205 -- create the required anonymous access type declarations, and if
21206 -- need be an incomplete type declaration for T itself.
21208 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
21210 if Ada_Version >= Ada_2005
21211 and then Present (Interface_List (Def))
21213 Check_Interfaces (N, Def);
21216 Ifaces_List : Elist_Id;
21219 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
21220 -- already in the parents.
21224 Ifaces_List => Ifaces_List,
21225 Exclude_Parents => True);
21227 Set_Interfaces (T, Ifaces_List);
21231 -- Records constitute a scope for the component declarations within.
21232 -- The scope is created prior to the processing of these declarations.
21233 -- Discriminants are processed first, so that they are visible when
21234 -- processing the other components. The Ekind of the record type itself
21235 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
21237 -- Enter record scope
21241 -- If an incomplete or private type declaration was already given for
21242 -- the type, then this scope already exists, and the discriminants have
21243 -- been declared within. We must verify that the full declaration
21244 -- matches the incomplete one.
21246 Check_Or_Process_Discriminants (N, T, Prev);
21248 Set_Is_Constrained (T, not Has_Discriminants (T));
21249 Set_Has_Delayed_Freeze (T, True);
21251 -- For tagged types add a manually analyzed component corresponding
21252 -- to the component _tag, the corresponding piece of tree will be
21253 -- expanded as part of the freezing actions if it is not a CPP_Class.
21257 -- Do not add the tag unless we are in expansion mode
21259 if Expander_Active then
21260 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21261 Enter_Name (Tag_Comp);
21263 Set_Ekind (Tag_Comp, E_Component);
21264 Set_Is_Tag (Tag_Comp);
21265 Set_Is_Aliased (Tag_Comp);
21266 Set_Etype (Tag_Comp, RTE (RE_Tag));
21267 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21268 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21269 Init_Component_Location (Tag_Comp);
21271 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21272 -- implemented interfaces.
21274 if Has_Interfaces (T) then
21275 Add_Interface_Tag_Components (N, T);
21279 Make_Class_Wide_Type (T);
21280 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21283 -- We must suppress range checks when processing record components in
21284 -- the presence of discriminants, since we don't want spurious checks to
21285 -- be generated during their analysis, but Suppress_Range_Checks flags
21286 -- must be reset the after processing the record definition.
21288 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21289 -- couldn't we just use the normal range check suppression method here.
21290 -- That would seem cleaner ???
21292 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21293 Set_Kill_Range_Checks (T, True);
21294 Record_Type_Definition (Def, Prev);
21295 Set_Kill_Range_Checks (T, False);
21297 Record_Type_Definition (Def, Prev);
21300 -- Exit from record scope
21304 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21305 -- the implemented interfaces and associate them an aliased entity.
21308 and then not Is_Empty_List (Interface_List (Def))
21310 Derive_Progenitor_Subprograms (T, T);
21313 Check_Function_Writable_Actuals (N);
21314 end Record_Type_Declaration;
21316 ----------------------------
21317 -- Record_Type_Definition --
21318 ----------------------------
21320 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21321 Component : Entity_Id;
21322 Ctrl_Components : Boolean := False;
21323 Final_Storage_Only : Boolean;
21327 if Ekind (Prev_T) = E_Incomplete_Type then
21328 T := Full_View (Prev_T);
21333 -- In SPARK, tagged types and type extensions may only be declared in
21334 -- the specification of library unit packages.
21336 if Present (Def) and then Is_Tagged_Type (T) then
21342 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21343 Typ := Parent (Def);
21346 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21347 Typ := Parent (Parent (Def));
21350 Ctxt := Parent (Typ);
21352 if Nkind (Ctxt) = N_Package_Body
21353 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21355 Check_SPARK_05_Restriction
21356 ("type should be defined in package specification", Typ);
21358 elsif Nkind (Ctxt) /= N_Package_Specification
21359 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21361 Check_SPARK_05_Restriction
21362 ("type should be defined in library unit package", Typ);
21367 Final_Storage_Only := not Is_Controlled_Active (T);
21369 -- Ada 2005: Check whether an explicit Limited is present in a derived
21370 -- type declaration.
21372 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21373 and then Limited_Present (Parent (Def))
21375 Set_Is_Limited_Record (T);
21378 -- If the component list of a record type is defined by the reserved
21379 -- word null and there is no discriminant part, then the record type has
21380 -- no components and all records of the type are null records (RM 3.7)
21381 -- This procedure is also called to process the extension part of a
21382 -- record extension, in which case the current scope may have inherited
21386 or else No (Component_List (Def))
21387 or else Null_Present (Component_List (Def))
21389 if not Is_Tagged_Type (T) then
21390 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21394 Analyze_Declarations (Component_Items (Component_List (Def)));
21396 if Present (Variant_Part (Component_List (Def))) then
21397 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21398 Analyze (Variant_Part (Component_List (Def)));
21402 -- After completing the semantic analysis of the record definition,
21403 -- record components, both new and inherited, are accessible. Set their
21404 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21405 -- whose Ekind may be void.
21407 Component := First_Entity (Current_Scope);
21408 while Present (Component) loop
21409 if Ekind (Component) = E_Void
21410 and then not Is_Itype (Component)
21412 Set_Ekind (Component, E_Component);
21413 Init_Component_Location (Component);
21416 Propagate_Concurrent_Flags (T, Etype (Component));
21418 if Ekind (Component) /= E_Component then
21421 -- Do not set Has_Controlled_Component on a class-wide equivalent
21422 -- type. See Make_CW_Equivalent_Type.
21424 elsif not Is_Class_Wide_Equivalent_Type (T)
21425 and then (Has_Controlled_Component (Etype (Component))
21426 or else (Chars (Component) /= Name_uParent
21427 and then Is_Controlled_Active
21428 (Etype (Component))))
21430 Set_Has_Controlled_Component (T, True);
21431 Final_Storage_Only :=
21433 and then Finalize_Storage_Only (Etype (Component));
21434 Ctrl_Components := True;
21437 Next_Entity (Component);
21440 -- A Type is Finalize_Storage_Only only if all its controlled components
21443 if Ctrl_Components then
21444 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21447 -- Place reference to end record on the proper entity, which may
21448 -- be a partial view.
21450 if Present (Def) then
21451 Process_End_Label (Def, 'e', Prev_T);
21453 end Record_Type_Definition;
21455 ------------------------
21456 -- Replace_Components --
21457 ------------------------
21459 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21460 function Process (N : Node_Id) return Traverse_Result;
21466 function Process (N : Node_Id) return Traverse_Result is
21470 if Nkind (N) = N_Discriminant_Specification then
21471 Comp := First_Discriminant (Typ);
21472 while Present (Comp) loop
21473 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21474 Set_Defining_Identifier (N, Comp);
21478 Next_Discriminant (Comp);
21481 elsif Nkind (N) = N_Component_Declaration then
21482 Comp := First_Component (Typ);
21483 while Present (Comp) loop
21484 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21485 Set_Defining_Identifier (N, Comp);
21489 Next_Component (Comp);
21496 procedure Replace is new Traverse_Proc (Process);
21498 -- Start of processing for Replace_Components
21502 end Replace_Components;
21504 -------------------------------
21505 -- Set_Completion_Referenced --
21506 -------------------------------
21508 procedure Set_Completion_Referenced (E : Entity_Id) is
21510 -- If in main unit, mark entity that is a completion as referenced,
21511 -- warnings go on the partial view when needed.
21513 if In_Extended_Main_Source_Unit (E) then
21514 Set_Referenced (E);
21516 end Set_Completion_Referenced;
21518 ---------------------
21519 -- Set_Default_SSO --
21520 ---------------------
21522 procedure Set_Default_SSO (T : Entity_Id) is
21524 case Opt.Default_SSO is
21528 Set_SSO_Set_Low_By_Default (T, True);
21530 Set_SSO_Set_High_By_Default (T, True);
21532 raise Program_Error;
21534 end Set_Default_SSO;
21536 ---------------------
21537 -- Set_Fixed_Range --
21538 ---------------------
21540 -- The range for fixed-point types is complicated by the fact that we
21541 -- do not know the exact end points at the time of the declaration. This
21542 -- is true for three reasons:
21544 -- A size clause may affect the fudging of the end-points.
21545 -- A small clause may affect the values of the end-points.
21546 -- We try to include the end-points if it does not affect the size.
21548 -- This means that the actual end-points must be established at the
21549 -- point when the type is frozen. Meanwhile, we first narrow the range
21550 -- as permitted (so that it will fit if necessary in a small specified
21551 -- size), and then build a range subtree with these narrowed bounds.
21552 -- Set_Fixed_Range constructs the range from real literal values, and
21553 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21555 -- The parent of this range is set to point to the entity so that it is
21556 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21557 -- other scalar types, which are just pointers to the range in the
21558 -- original tree, this would otherwise be an orphan).
21560 -- The tree is left unanalyzed. When the type is frozen, the processing
21561 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21562 -- analyzed, and uses this as an indication that it should complete
21563 -- work on the range (it will know the final small and size values).
21565 procedure Set_Fixed_Range
21571 S : constant Node_Id :=
21573 Low_Bound => Make_Real_Literal (Loc, Lo),
21574 High_Bound => Make_Real_Literal (Loc, Hi));
21576 Set_Scalar_Range (E, S);
21579 -- Before the freeze point, the bounds of a fixed point are universal
21580 -- and carry the corresponding type.
21582 Set_Etype (Low_Bound (S), Universal_Real);
21583 Set_Etype (High_Bound (S), Universal_Real);
21584 end Set_Fixed_Range;
21586 ----------------------------------
21587 -- Set_Scalar_Range_For_Subtype --
21588 ----------------------------------
21590 procedure Set_Scalar_Range_For_Subtype
21591 (Def_Id : Entity_Id;
21595 Kind : constant Entity_Kind := Ekind (Def_Id);
21598 -- Defend against previous error
21600 if Nkind (R) = N_Error then
21604 Set_Scalar_Range (Def_Id, R);
21606 -- We need to link the range into the tree before resolving it so
21607 -- that types that are referenced, including importantly the subtype
21608 -- itself, are properly frozen (Freeze_Expression requires that the
21609 -- expression be properly linked into the tree). Of course if it is
21610 -- already linked in, then we do not disturb the current link.
21612 if No (Parent (R)) then
21613 Set_Parent (R, Def_Id);
21616 -- Reset the kind of the subtype during analysis of the range, to
21617 -- catch possible premature use in the bounds themselves.
21619 Set_Ekind (Def_Id, E_Void);
21620 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21621 Set_Ekind (Def_Id, Kind);
21622 end Set_Scalar_Range_For_Subtype;
21624 --------------------------------------------------------
21625 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21626 --------------------------------------------------------
21628 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21632 -- Make sure set if encountered during Expand_To_Stored_Constraint
21634 Set_Stored_Constraint (E, No_Elist);
21636 -- Give it the right value
21638 if Is_Constrained (E) and then Has_Discriminants (E) then
21639 Set_Stored_Constraint (E,
21640 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21642 end Set_Stored_Constraint_From_Discriminant_Constraint;
21644 -------------------------------------
21645 -- Signed_Integer_Type_Declaration --
21646 -------------------------------------
21648 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21649 Implicit_Base : Entity_Id;
21650 Base_Typ : Entity_Id;
21653 Errs : Boolean := False;
21657 function Can_Derive_From (E : Entity_Id) return Boolean;
21658 -- Determine whether given bounds allow derivation from specified type
21660 procedure Check_Bound (Expr : Node_Id);
21661 -- Check bound to make sure it is integral and static. If not, post
21662 -- appropriate error message and set Errs flag
21664 ---------------------
21665 -- Can_Derive_From --
21666 ---------------------
21668 -- Note we check both bounds against both end values, to deal with
21669 -- strange types like ones with a range of 0 .. -12341234.
21671 function Can_Derive_From (E : Entity_Id) return Boolean is
21672 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21673 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21675 return Lo <= Lo_Val and then Lo_Val <= Hi
21677 Lo <= Hi_Val and then Hi_Val <= Hi;
21678 end Can_Derive_From;
21684 procedure Check_Bound (Expr : Node_Id) is
21686 -- If a range constraint is used as an integer type definition, each
21687 -- bound of the range must be defined by a static expression of some
21688 -- integer type, but the two bounds need not have the same integer
21689 -- type (Negative bounds are allowed.) (RM 3.5.4)
21691 if not Is_Integer_Type (Etype (Expr)) then
21693 ("integer type definition bounds must be of integer type", Expr);
21696 elsif not Is_OK_Static_Expression (Expr) then
21697 Flag_Non_Static_Expr
21698 ("non-static expression used for integer type bound!", Expr);
21701 -- The bounds are folded into literals, and we set their type to be
21702 -- universal, to avoid typing difficulties: we cannot set the type
21703 -- of the literal to the new type, because this would be a forward
21704 -- reference for the back end, and if the original type is user-
21705 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21708 if Is_Entity_Name (Expr) then
21709 Fold_Uint (Expr, Expr_Value (Expr), True);
21712 Set_Etype (Expr, Universal_Integer);
21716 -- Start of processing for Signed_Integer_Type_Declaration
21719 -- Create an anonymous base type
21722 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21724 -- Analyze and check the bounds, they can be of any integer type
21726 Lo := Low_Bound (Def);
21727 Hi := High_Bound (Def);
21729 -- Arbitrarily use Integer as the type if either bound had an error
21731 if Hi = Error or else Lo = Error then
21732 Base_Typ := Any_Integer;
21733 Set_Error_Posted (T, True);
21735 -- Here both bounds are OK expressions
21738 Analyze_And_Resolve (Lo, Any_Integer);
21739 Analyze_And_Resolve (Hi, Any_Integer);
21745 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21746 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21749 -- Find type to derive from
21751 Lo_Val := Expr_Value (Lo);
21752 Hi_Val := Expr_Value (Hi);
21754 if Can_Derive_From (Standard_Short_Short_Integer) then
21755 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21757 elsif Can_Derive_From (Standard_Short_Integer) then
21758 Base_Typ := Base_Type (Standard_Short_Integer);
21760 elsif Can_Derive_From (Standard_Integer) then
21761 Base_Typ := Base_Type (Standard_Integer);
21763 elsif Can_Derive_From (Standard_Long_Integer) then
21764 Base_Typ := Base_Type (Standard_Long_Integer);
21766 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21767 Check_Restriction (No_Long_Long_Integers, Def);
21768 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21771 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21772 Error_Msg_N ("integer type definition bounds out of range", Def);
21773 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21774 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21778 -- Complete both implicit base and declared first subtype entities. The
21779 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21780 -- are not clobbered when the signed integer type acts as a full view of
21783 Set_Etype (Implicit_Base, Base_Typ);
21784 Set_Size_Info (Implicit_Base, Base_Typ);
21785 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21786 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21787 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21789 Set_Ekind (T, E_Signed_Integer_Subtype);
21790 Set_Etype (T, Implicit_Base);
21791 Set_Size_Info (T, Implicit_Base);
21792 Inherit_Rep_Item_Chain (T, Implicit_Base);
21793 Set_Scalar_Range (T, Def);
21794 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21795 Set_Is_Constrained (T);
21796 end Signed_Integer_Type_Declaration;