1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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 Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Prag; use Sem_Prag;
65 with Sem_Res; use Sem_Res;
66 with Sem_Smem; use Sem_Smem;
67 with Sem_Type; use Sem_Type;
68 with Sem_Util; use Sem_Util;
69 with Sem_Warn; use Sem_Warn;
70 with Stand; use Stand;
71 with Sinfo; use Sinfo;
72 with Sinput; use Sinput;
73 with Snames; use Snames;
74 with Targparm; use Targparm;
75 with Tbuild; use Tbuild;
76 with Ttypes; use Ttypes;
77 with Uintp; use Uintp;
78 with Urealp; use Urealp;
80 package body Sem_Ch3 is
82 -----------------------
83 -- Local Subprograms --
84 -----------------------
86 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
87 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
88 -- abstract interface types implemented by a record type or a derived
91 procedure Build_Derived_Type
93 Parent_Type : Entity_Id;
94 Derived_Type : Entity_Id;
95 Is_Completion : Boolean;
96 Derive_Subps : Boolean := True);
97 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
98 -- the N_Full_Type_Declaration node containing the derived type definition.
99 -- Parent_Type is the entity for the parent type in the derived type
100 -- definition and Derived_Type the actual derived type. Is_Completion must
101 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
102 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
103 -- completion of a private type declaration. If Is_Completion is set to
104 -- True, N is the completion of a private type declaration and Derived_Type
105 -- is different from the defining identifier inside N (i.e. Derived_Type /=
106 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
107 -- subprograms should be derived. The only case where this parameter is
108 -- False is when Build_Derived_Type is recursively called to process an
109 -- implicit derived full type for a type derived from a private type (in
110 -- that case the subprograms must only be derived for the private view of
113 -- ??? These flags need a bit of re-examination and re-documentation:
114 -- ??? are they both necessary (both seem related to the recursion)?
116 procedure Build_Derived_Access_Type
118 Parent_Type : Entity_Id;
119 Derived_Type : Entity_Id);
120 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
121 -- create an implicit base if the parent type is constrained or if the
122 -- subtype indication has a constraint.
124 procedure Build_Derived_Array_Type
126 Parent_Type : Entity_Id;
127 Derived_Type : Entity_Id);
128 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
129 -- create an implicit base if the parent type is constrained or if the
130 -- subtype indication has a constraint.
132 procedure Build_Derived_Concurrent_Type
134 Parent_Type : Entity_Id;
135 Derived_Type : Entity_Id);
136 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
137 -- protected type, inherit entries and protected subprograms, check
138 -- legality of discriminant constraints if any.
140 procedure Build_Derived_Enumeration_Type
142 Parent_Type : Entity_Id;
143 Derived_Type : Entity_Id);
144 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
145 -- type, we must create a new list of literals. Types derived from
146 -- Character and [Wide_]Wide_Character are special-cased.
148 procedure Build_Derived_Numeric_Type
150 Parent_Type : Entity_Id;
151 Derived_Type : Entity_Id);
152 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
153 -- an anonymous base type, and propagate constraint to subtype if needed.
155 procedure Build_Derived_Private_Type
157 Parent_Type : Entity_Id;
158 Derived_Type : Entity_Id;
159 Is_Completion : Boolean;
160 Derive_Subps : Boolean := True);
161 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
162 -- because the parent may or may not have a completion, and the derivation
163 -- may itself be a completion.
165 procedure Build_Derived_Record_Type
167 Parent_Type : Entity_Id;
168 Derived_Type : Entity_Id;
169 Derive_Subps : Boolean := True);
170 -- Subsidiary procedure for Build_Derived_Type and
171 -- Analyze_Private_Extension_Declaration used for tagged and untagged
172 -- record types. All parameters are as in Build_Derived_Type except that
173 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
174 -- N_Private_Extension_Declaration node. See the definition of this routine
175 -- for much more info. Derive_Subps indicates whether subprograms should
176 -- be derived from the parent type. The only case where Derive_Subps is
177 -- False is for an implicit derived full type for a type derived from a
178 -- private type (see Build_Derived_Type).
180 procedure Build_Discriminal (Discrim : Entity_Id);
181 -- Create the discriminal corresponding to discriminant Discrim, that is
182 -- the parameter corresponding to Discrim to be used in initialization
183 -- procedures for the type where Discrim is a discriminant. Discriminals
184 -- are not used during semantic analysis, and are not fully defined
185 -- entities until expansion. Thus they are not given a scope until
186 -- initialization procedures are built.
188 function Build_Discriminant_Constraints
191 Derived_Def : Boolean := False) return Elist_Id;
192 -- Validate discriminant constraints and return the list of the constraints
193 -- in order of discriminant declarations, where T is the discriminated
194 -- unconstrained type. Def is the N_Subtype_Indication node where the
195 -- discriminants constraints for T are specified. Derived_Def is True
196 -- when building the discriminant constraints in a derived type definition
197 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
198 -- type and Def is the constraint "(xxx)" on T and this routine sets the
199 -- Corresponding_Discriminant field of the discriminants in the derived
200 -- type D to point to the corresponding discriminants in the parent type T.
202 procedure Build_Discriminated_Subtype
206 Related_Nod : Node_Id;
207 For_Access : Boolean := False);
208 -- Subsidiary procedure to Constrain_Discriminated_Type and to
209 -- Process_Incomplete_Dependents. Given
211 -- T (a possibly discriminated base type)
212 -- Def_Id (a very partially built subtype for T),
214 -- the call completes Def_Id to be the appropriate E_*_Subtype.
216 -- The Elist is the list of discriminant constraints if any (it is set
217 -- to No_Elist if T is not a discriminated type, and to an empty list if
218 -- T has discriminants but there are no discriminant constraints). The
219 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
220 -- The For_Access says whether or not this subtype is really constraining
221 -- an access type. That is its sole purpose is the designated type of an
222 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
223 -- is built to avoid freezing T when the access subtype is frozen.
225 function Build_Scalar_Bound
228 Der_T : Entity_Id) return Node_Id;
229 -- The bounds of a derived scalar type are conversions of the bounds of
230 -- the parent type. Optimize the representation if the bounds are literals.
231 -- Needs a more complete spec--what are the parameters exactly, and what
232 -- exactly is the returned value, and how is Bound affected???
234 procedure Build_Underlying_Full_View
238 -- If the completion of a private type is itself derived from a private
239 -- type, or if the full view of a private subtype is itself private, the
240 -- back-end has no way to compute the actual size of this type. We build
241 -- an internal subtype declaration of the proper parent type to convey
242 -- this information. This extra mechanism is needed because a full
243 -- view cannot itself have a full view (it would get clobbered during
246 procedure Check_Access_Discriminant_Requires_Limited
249 -- Check the restriction that the type to which an access discriminant
250 -- belongs must be a concurrent type or a descendant of a type with
251 -- the reserved word 'limited' in its declaration.
253 procedure Check_Anonymous_Access_Components
257 Comp_List : Node_Id);
258 -- Ada 2005 AI-382: an access component in a record definition can refer to
259 -- the enclosing record, in which case it denotes the type itself, and not
260 -- the current instance of the type. We create an anonymous access type for
261 -- the component, and flag it as an access to a component, so accessibility
262 -- checks are properly performed on it. The declaration of the access type
263 -- is placed ahead of that of the record to prevent order-of-elaboration
264 -- circularity issues in Gigi. We create an incomplete type for the record
265 -- declaration, which is the designated type of the anonymous access.
267 procedure Check_Delta_Expression (E : Node_Id);
268 -- Check that the expression represented by E is suitable for use as a
269 -- delta expression, i.e. it is of real type and is static.
271 procedure Check_Digits_Expression (E : Node_Id);
272 -- Check that the expression represented by E is suitable for use as a
273 -- digits expression, i.e. it is of integer type, positive and static.
275 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
276 -- Validate the initialization of an object declaration. T is the required
277 -- type, and Exp is the initialization expression.
279 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
280 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
282 procedure Check_Or_Process_Discriminants
285 Prev : Entity_Id := Empty);
286 -- If N is the full declaration of the completion T of an incomplete or
287 -- private type, check its discriminants (which are already known to be
288 -- conformant with those of the partial view, see Find_Type_Name),
289 -- otherwise process them. Prev is the entity of the partial declaration,
292 procedure Check_Real_Bound (Bound : Node_Id);
293 -- Check given bound for being of real type and static. If not, post an
294 -- appropriate message, and rewrite the bound with the real literal zero.
296 procedure Constant_Redeclaration
300 -- Various checks on legality of full declaration of deferred constant.
301 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
302 -- node. The caller has not yet set any attributes of this entity.
304 function Contain_Interface
306 Ifaces : Elist_Id) return Boolean;
307 -- Ada 2005: Determine whether Iface is present in the list Ifaces
309 procedure Convert_Scalar_Bounds
311 Parent_Type : Entity_Id;
312 Derived_Type : Entity_Id;
314 -- For derived scalar types, convert the bounds in the type definition to
315 -- the derived type, and complete their analysis. Given a constraint of the
316 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
317 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
318 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
319 -- subtype are conversions of those bounds to the derived_type, so that
320 -- their typing is consistent.
322 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array base type T2 to array base type T1. Copies
324 -- only attributes that apply to base types, but not subtypes.
326 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
327 -- Copies attributes from array subtype T2 to array subtype T1. Copies
328 -- attributes that apply to both subtypes and base types.
330 procedure Create_Constrained_Components
334 Constraints : Elist_Id);
335 -- Build the list of entities for a constrained discriminated record
336 -- subtype. If a component depends on a discriminant, replace its subtype
337 -- using the discriminant values in the discriminant constraint. Subt
338 -- is the defining identifier for the subtype whose list of constrained
339 -- entities we will create. Decl_Node is the type declaration node where
340 -- we will attach all the itypes created. Typ is the base discriminated
341 -- type for the subtype Subt. Constraints is the list of discriminant
342 -- constraints for Typ.
344 function Constrain_Component_Type
346 Constrained_Typ : Entity_Id;
347 Related_Node : Node_Id;
349 Constraints : Elist_Id) return Entity_Id;
350 -- Given a discriminated base type Typ, a list of discriminant constraint
351 -- Constraints for Typ and a component of Typ, with type Compon_Type,
352 -- create and return the type corresponding to Compon_type where all
353 -- discriminant references are replaced with the corresponding constraint.
354 -- If no discriminant references occur in Compon_Typ then return it as is.
355 -- Constrained_Typ is the final constrained subtype to which the
356 -- constrained Compon_Type belongs. Related_Node is the node where we will
357 -- attach all the itypes created.
359 -- Above description is confused, what is Compon_Type???
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id;
413 Related_Id : Entity_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
527 -- implicit 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 function Is_Valid_Constraint_Kind
582 Constraint_Kind : Node_Kind) return Boolean;
583 -- Returns True if it is legal to apply the given kind of constraint to the
584 -- given kind of type (index constraint to an array type, for example).
586 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
587 -- Create new modular type. Verify that modulus is in bounds
589 procedure New_Concatenation_Op (Typ : Entity_Id);
590 -- Create an abbreviated declaration for an operator in order to
591 -- materialize concatenation on array types.
593 procedure Ordinary_Fixed_Point_Type_Declaration
596 -- Create a new ordinary fixed point type, and apply the constraint to
597 -- obtain subtype of it.
599 procedure Prepare_Private_Subtype_Completion
601 Related_Nod : Node_Id);
602 -- Id is a subtype of some private type. Creates the full declaration
603 -- associated with Id whenever possible, i.e. when the full declaration
604 -- of the base type is already known. Records each subtype into
605 -- Private_Dependents of the base type.
607 procedure Process_Incomplete_Dependents
611 -- Process all entities that depend on an incomplete type. There include
612 -- subtypes, subprogram types that mention the incomplete type in their
613 -- profiles, and subprogram with access parameters that designate the
616 -- Inc_T is the defining identifier of an incomplete type declaration, its
617 -- Ekind is E_Incomplete_Type.
619 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
621 -- Full_T is N's defining identifier.
623 -- Subtypes of incomplete types with discriminants are completed when the
624 -- parent type is. This is simpler than private subtypes, because they can
625 -- only appear in the same scope, and there is no need to exchange views.
626 -- Similarly, access_to_subprogram types may have a parameter or a return
627 -- type that is an incomplete type, and that must be replaced with the
630 -- If the full type is tagged, subprogram with access parameters that
631 -- designated the incomplete may be primitive operations of the full type,
632 -- and have to be processed accordingly.
634 procedure Process_Real_Range_Specification (Def : Node_Id);
635 -- Given the type definition for a real type, this procedure processes and
636 -- checks the real range specification of this type definition if one is
637 -- present. If errors are found, error messages are posted, and the
638 -- Real_Range_Specification of Def is reset to Empty.
640 procedure Record_Type_Declaration
644 -- Process a record type declaration (for both untagged and tagged
645 -- records). Parameters T and N are exactly like in procedure
646 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
647 -- for this routine. If this is the completion of an incomplete type
648 -- declaration, Prev is the entity of the incomplete declaration, used for
649 -- cross-referencing. Otherwise Prev = T.
651 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
652 -- This routine is used to process the actual record type definition (both
653 -- for untagged and tagged records). Def is a record type definition node.
654 -- This procedure analyzes the components in this record type definition.
655 -- Prev_T is the entity for the enclosing record type. It is provided so
656 -- that its Has_Task flag can be set if any of the component have Has_Task
657 -- set. If the declaration is the completion of an incomplete type
658 -- declaration, Prev_T is the original incomplete type, whose full view is
661 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
662 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
663 -- build a copy of the declaration tree of the parent, and we create
664 -- independently the list of components for the derived type. Semantic
665 -- information uses the component entities, but record representation
666 -- clauses are validated on the declaration tree. This procedure replaces
667 -- discriminants and components in the declaration with those that have
668 -- been created by Inherit_Components.
670 procedure Set_Fixed_Range
675 -- Build a range node with the given bounds and set it as the Scalar_Range
676 -- of the given fixed-point type entity. Loc is the source location used
677 -- for the constructed range. See body for further details.
679 procedure Set_Scalar_Range_For_Subtype
683 -- This routine is used to set the scalar range field for a subtype given
684 -- Def_Id, the entity for the subtype, and R, the range expression for the
685 -- scalar range. Subt provides the parent subtype to be used to analyze,
686 -- resolve, and check the given range.
688 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
689 -- Create a new signed integer entity, and apply the constraint to obtain
690 -- the required first named subtype of this type.
692 procedure Set_Stored_Constraint_From_Discriminant_Constraint
694 -- E is some record type. This routine computes E's Stored_Constraint
695 -- from its Discriminant_Constraint.
697 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
698 -- Check that an entity in a list of progenitors is an interface,
699 -- emit error otherwise.
701 -----------------------
702 -- Access_Definition --
703 -----------------------
705 function Access_Definition
706 (Related_Nod : Node_Id;
707 N : Node_Id) return Entity_Id
709 Loc : constant Source_Ptr := Sloc (Related_Nod);
710 Anon_Type : Entity_Id;
711 Anon_Scope : Entity_Id;
712 Desig_Type : Entity_Id;
714 Enclosing_Prot_Type : Entity_Id := Empty;
717 Check_SPARK_Restriction ("access type is not allowed", N);
719 if Is_Entry (Current_Scope)
720 and then Is_Task_Type (Etype (Scope (Current_Scope)))
722 Error_Msg_N ("task entries cannot have access parameters", N);
726 -- Ada 2005: for an object declaration the corresponding anonymous
727 -- type is declared in the current scope.
729 -- If the access definition is the return type of another access to
730 -- function, scope is the current one, because it is the one of the
731 -- current type declaration.
733 if Nkind_In (Related_Nod, N_Object_Declaration,
734 N_Access_Function_Definition)
736 Anon_Scope := Current_Scope;
738 -- For the anonymous function result case, retrieve the scope of the
739 -- function specification's associated entity rather than using the
740 -- current scope. The current scope will be the function itself if the
741 -- formal part is currently being analyzed, but will be the parent scope
742 -- in the case of a parameterless function, and we always want to use
743 -- the function's parent scope. Finally, if the function is a child
744 -- unit, we must traverse the tree to retrieve the proper entity.
746 elsif Nkind (Related_Nod) = N_Function_Specification
747 and then Nkind (Parent (N)) /= N_Parameter_Specification
749 -- If the current scope is a protected type, the anonymous access
750 -- is associated with one of the protected operations, and must
751 -- be available in the scope that encloses the protected declaration.
752 -- Otherwise the type is in the scope enclosing the subprogram.
754 -- If the function has formals, The return type of a subprogram
755 -- declaration is analyzed in the scope of the subprogram (see
756 -- Process_Formals) and thus the protected type, if present, is
757 -- the scope of the current function scope.
759 if Ekind (Current_Scope) = E_Protected_Type then
760 Enclosing_Prot_Type := Current_Scope;
762 elsif Ekind (Current_Scope) = E_Function
763 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
765 Enclosing_Prot_Type := Scope (Current_Scope);
768 if Present (Enclosing_Prot_Type) then
769 Anon_Scope := Scope (Enclosing_Prot_Type);
772 Anon_Scope := Scope (Defining_Entity (Related_Nod));
776 -- For access formals, access components, and access discriminants,
777 -- the scope is that of the enclosing declaration,
779 Anon_Scope := Scope (Current_Scope);
784 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
787 and then Ada_Version >= Ada_2005
789 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
792 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
793 -- the corresponding semantic routine
795 if Present (Access_To_Subprogram_Definition (N)) then
796 Access_Subprogram_Declaration
797 (T_Name => Anon_Type,
798 T_Def => Access_To_Subprogram_Definition (N));
800 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
802 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
805 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
808 Set_Can_Use_Internal_Rep
809 (Anon_Type, not Always_Compatible_Rep_On_Target);
811 -- If the anonymous access is associated with a protected operation
812 -- create a reference to it after the enclosing protected definition
813 -- because the itype will be used in the subsequent bodies.
815 if Ekind (Current_Scope) = E_Protected_Type then
816 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
822 Find_Type (Subtype_Mark (N));
823 Desig_Type := Entity (Subtype_Mark (N));
825 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
826 Set_Etype (Anon_Type, Anon_Type);
828 -- Make sure the anonymous access type has size and alignment fields
829 -- set, as required by gigi. This is necessary in the case of the
830 -- Task_Body_Procedure.
832 if not Has_Private_Component (Desig_Type) then
833 Layout_Type (Anon_Type);
836 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
837 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
838 -- the null value is allowed. In Ada 95 the null value is never allowed.
840 if Ada_Version >= Ada_2005 then
841 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
843 Set_Can_Never_Be_Null (Anon_Type, True);
846 -- The anonymous access type is as public as the discriminated type or
847 -- subprogram that defines it. It is imported (for back-end purposes)
848 -- if the designated type is.
850 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
852 -- Ada 2005 (AI-231): Propagate the access-constant attribute
854 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
856 -- The context is either a subprogram declaration, object declaration,
857 -- or an access discriminant, in a private or a full type declaration.
858 -- In the case of a subprogram, if the designated type is incomplete,
859 -- the operation will be a primitive operation of the full type, to be
860 -- updated subsequently. If the type is imported through a limited_with
861 -- clause, the subprogram is not a primitive operation of the type
862 -- (which is declared elsewhere in some other scope).
864 if Ekind (Desig_Type) = E_Incomplete_Type
865 and then not From_With_Type (Desig_Type)
866 and then Is_Overloadable (Current_Scope)
868 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
869 Set_Has_Delayed_Freeze (Current_Scope);
872 -- Ada 2005: if the designated type is an interface that may contain
873 -- tasks, create a Master entity for the declaration. This must be done
874 -- before expansion of the full declaration, because the declaration may
875 -- include an expression that is an allocator, whose expansion needs the
876 -- proper Master for the created tasks.
878 if Nkind (Related_Nod) = N_Object_Declaration
879 and then Expander_Active
881 if Is_Interface (Desig_Type)
882 and then Is_Limited_Record (Desig_Type)
884 Build_Class_Wide_Master (Anon_Type);
886 -- Similarly, if the type is an anonymous access that designates
887 -- tasks, create a master entity for it in the current context.
889 elsif Has_Task (Desig_Type)
890 and then Comes_From_Source (Related_Nod)
891 and then not Restriction_Active (No_Task_Hierarchy)
893 if not Has_Master_Entity (Current_Scope) then
895 Make_Object_Declaration (Loc,
896 Defining_Identifier =>
897 Make_Defining_Identifier (Loc, Name_uMaster),
898 Constant_Present => True,
900 New_Reference_To (RTE (RE_Master_Id), Loc),
902 Make_Explicit_Dereference (Loc,
903 New_Reference_To (RTE (RE_Current_Master), Loc)));
905 Insert_Before (Related_Nod, Decl);
908 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
909 Set_Has_Master_Entity (Current_Scope);
911 Build_Master_Renaming (Related_Nod, Anon_Type);
916 -- For a private component of a protected type, it is imperative that
917 -- the back-end elaborate the type immediately after the protected
918 -- declaration, because this type will be used in the declarations
919 -- created for the component within each protected body, so we must
920 -- create an itype reference for it now.
922 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
923 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
925 -- Similarly, if the access definition is the return result of a
926 -- function, create an itype reference for it because it will be used
927 -- within the function body. For a regular function that is not a
928 -- compilation unit, insert reference after the declaration. For a
929 -- protected operation, insert it after the enclosing protected type
930 -- declaration. In either case, do not create a reference for a type
931 -- obtained through a limited_with clause, because this would introduce
932 -- semantic dependencies.
934 -- Similarly, do not create a reference if the designated type is a
935 -- generic formal, because no use of it will reach the backend.
937 elsif Nkind (Related_Nod) = N_Function_Specification
938 and then not From_With_Type (Desig_Type)
939 and then not Is_Generic_Type (Desig_Type)
941 if Present (Enclosing_Prot_Type) then
942 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
944 elsif Is_List_Member (Parent (Related_Nod))
945 and then Nkind (Parent (N)) /= N_Parameter_Specification
947 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
950 -- Finally, create an itype reference for an object declaration of an
951 -- anonymous access type. This is strictly necessary only for deferred
952 -- constants, but in any case will avoid out-of-scope problems in the
955 elsif Nkind (Related_Nod) = N_Object_Declaration then
956 Build_Itype_Reference (Anon_Type, Related_Nod);
960 end Access_Definition;
962 -----------------------------------
963 -- Access_Subprogram_Declaration --
964 -----------------------------------
966 procedure Access_Subprogram_Declaration
971 procedure Check_For_Premature_Usage (Def : Node_Id);
972 -- Check that type T_Name is not used, directly or recursively, as a
973 -- parameter or a return type in Def. Def is either a subtype, an
974 -- access_definition, or an access_to_subprogram_definition.
976 -------------------------------
977 -- Check_For_Premature_Usage --
978 -------------------------------
980 procedure Check_For_Premature_Usage (Def : Node_Id) is
984 -- Check for a subtype mark
986 if Nkind (Def) in N_Has_Etype then
987 if Etype (Def) = T_Name then
989 ("type& cannot be used before end of its declaration", Def);
992 -- If this is not a subtype, then this is an access_definition
994 elsif Nkind (Def) = N_Access_Definition then
995 if Present (Access_To_Subprogram_Definition (Def)) then
996 Check_For_Premature_Usage
997 (Access_To_Subprogram_Definition (Def));
999 Check_For_Premature_Usage (Subtype_Mark (Def));
1002 -- The only cases left are N_Access_Function_Definition and
1003 -- N_Access_Procedure_Definition.
1006 if Present (Parameter_Specifications (Def)) then
1007 Param := First (Parameter_Specifications (Def));
1008 while Present (Param) loop
1009 Check_For_Premature_Usage (Parameter_Type (Param));
1010 Param := Next (Param);
1014 if Nkind (Def) = N_Access_Function_Definition then
1015 Check_For_Premature_Usage (Result_Definition (Def));
1018 end Check_For_Premature_Usage;
1022 Formals : constant List_Id := Parameter_Specifications (T_Def);
1025 Desig_Type : constant Entity_Id :=
1026 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1028 -- Start of processing for Access_Subprogram_Declaration
1031 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1033 -- Associate the Itype node with the inner full-type declaration or
1034 -- subprogram spec or entry body. This is required to handle nested
1035 -- anonymous declarations. For example:
1038 -- (X : access procedure
1039 -- (Y : access procedure
1042 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1043 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1044 N_Private_Type_Declaration,
1045 N_Private_Extension_Declaration,
1046 N_Procedure_Specification,
1047 N_Function_Specification,
1051 Nkind_In (D_Ityp, N_Object_Declaration,
1052 N_Object_Renaming_Declaration,
1053 N_Formal_Object_Declaration,
1054 N_Formal_Type_Declaration,
1055 N_Task_Type_Declaration,
1056 N_Protected_Type_Declaration))
1058 D_Ityp := Parent (D_Ityp);
1059 pragma Assert (D_Ityp /= Empty);
1062 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1064 if Nkind_In (D_Ityp, N_Procedure_Specification,
1065 N_Function_Specification)
1067 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1069 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1070 N_Object_Declaration,
1071 N_Object_Renaming_Declaration,
1072 N_Formal_Type_Declaration)
1074 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1077 if Nkind (T_Def) = N_Access_Function_Definition then
1078 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1080 Acc : constant Node_Id := Result_Definition (T_Def);
1083 if Present (Access_To_Subprogram_Definition (Acc))
1085 Protected_Present (Access_To_Subprogram_Definition (Acc))
1089 Replace_Anonymous_Access_To_Protected_Subprogram
1095 Access_Definition (T_Def, Result_Definition (T_Def)));
1100 Analyze (Result_Definition (T_Def));
1103 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1106 -- If a null exclusion is imposed on the result type, then
1107 -- create a null-excluding itype (an access subtype) and use
1108 -- it as the function's Etype.
1110 if Is_Access_Type (Typ)
1111 and then Null_Exclusion_In_Return_Present (T_Def)
1113 Set_Etype (Desig_Type,
1114 Create_Null_Excluding_Itype
1116 Related_Nod => T_Def,
1117 Scope_Id => Current_Scope));
1120 if From_With_Type (Typ) then
1122 -- AI05-151: Incomplete types are allowed in all basic
1123 -- declarations, including access to subprograms.
1125 if Ada_Version >= Ada_2012 then
1130 ("illegal use of incomplete type&",
1131 Result_Definition (T_Def), Typ);
1134 elsif Ekind (Current_Scope) = E_Package
1135 and then In_Private_Part (Current_Scope)
1137 if Ekind (Typ) = E_Incomplete_Type then
1138 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1140 elsif Is_Class_Wide_Type (Typ)
1141 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1144 (Desig_Type, Private_Dependents (Etype (Typ)));
1148 Set_Etype (Desig_Type, Typ);
1153 if not (Is_Type (Etype (Desig_Type))) then
1155 ("expect type in function specification",
1156 Result_Definition (T_Def));
1160 Set_Etype (Desig_Type, Standard_Void_Type);
1163 if Present (Formals) then
1164 Push_Scope (Desig_Type);
1166 -- A bit of a kludge here. These kludges will be removed when Itypes
1167 -- have proper parent pointers to their declarations???
1169 -- Kludge 1) Link defining_identifier of formals. Required by
1170 -- First_Formal to provide its functionality.
1176 F := First (Formals);
1178 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1179 -- when it is part of an unconstrained type and subtype expansion
1180 -- is disabled. To avoid back-end problems with shared profiles,
1181 -- use previous subprogram type as the designated type.
1184 and then Present (Scope (Defining_Identifier (F)))
1186 Set_Etype (T_Name, T_Name);
1187 Init_Size_Align (T_Name);
1188 Set_Directly_Designated_Type (T_Name,
1189 Scope (Defining_Identifier (F)));
1193 while Present (F) loop
1194 if No (Parent (Defining_Identifier (F))) then
1195 Set_Parent (Defining_Identifier (F), F);
1202 Process_Formals (Formals, Parent (T_Def));
1204 -- Kludge 2) End_Scope requires that the parent pointer be set to
1205 -- something reasonable, but Itypes don't have parent pointers. So
1206 -- we set it and then unset it ???
1208 Set_Parent (Desig_Type, T_Name);
1210 Set_Parent (Desig_Type, Empty);
1213 -- Check for premature usage of the type being defined
1215 Check_For_Premature_Usage (T_Def);
1217 -- The return type and/or any parameter type may be incomplete. Mark
1218 -- the subprogram_type as depending on the incomplete type, so that
1219 -- it can be updated when the full type declaration is seen. This
1220 -- only applies to incomplete types declared in some enclosing scope,
1221 -- not to limited views from other packages.
1223 if Present (Formals) then
1224 Formal := First_Formal (Desig_Type);
1225 while Present (Formal) loop
1226 if Ekind (Formal) /= E_In_Parameter
1227 and then Nkind (T_Def) = N_Access_Function_Definition
1229 Error_Msg_N ("functions can only have IN parameters", Formal);
1232 if Ekind (Etype (Formal)) = E_Incomplete_Type
1233 and then In_Open_Scopes (Scope (Etype (Formal)))
1235 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1236 Set_Has_Delayed_Freeze (Desig_Type);
1239 Next_Formal (Formal);
1243 -- If the return type is incomplete, this is legal as long as the
1244 -- type is declared in the current scope and will be completed in
1245 -- it (rather than being part of limited view).
1247 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1248 and then not Has_Delayed_Freeze (Desig_Type)
1249 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1251 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1252 Set_Has_Delayed_Freeze (Desig_Type);
1255 Check_Delayed_Subprogram (Desig_Type);
1257 if Protected_Present (T_Def) then
1258 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1259 Set_Convention (Desig_Type, Convention_Protected);
1261 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1264 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1266 Set_Etype (T_Name, T_Name);
1267 Init_Size_Align (T_Name);
1268 Set_Directly_Designated_Type (T_Name, Desig_Type);
1270 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1272 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1274 Check_Restriction (No_Access_Subprograms, T_Def);
1275 end Access_Subprogram_Declaration;
1277 ----------------------------
1278 -- Access_Type_Declaration --
1279 ----------------------------
1281 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1282 S : constant Node_Id := Subtype_Indication (Def);
1283 P : constant Node_Id := Parent (Def);
1285 Check_SPARK_Restriction ("access type is not allowed", Def);
1287 -- Check for permissible use of incomplete type
1289 if Nkind (S) /= N_Subtype_Indication then
1292 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1293 Set_Directly_Designated_Type (T, Entity (S));
1295 Set_Directly_Designated_Type (T,
1296 Process_Subtype (S, P, T, 'P'));
1300 Set_Directly_Designated_Type (T,
1301 Process_Subtype (S, P, T, 'P'));
1304 if All_Present (Def) or Constant_Present (Def) then
1305 Set_Ekind (T, E_General_Access_Type);
1307 Set_Ekind (T, E_Access_Type);
1310 if Base_Type (Designated_Type (T)) = T then
1311 Error_Msg_N ("access type cannot designate itself", S);
1313 -- In Ada 2005, the type may have a limited view through some unit
1314 -- in its own context, allowing the following circularity that cannot
1315 -- be detected earlier
1317 elsif Is_Class_Wide_Type (Designated_Type (T))
1318 and then Etype (Designated_Type (T)) = T
1321 ("access type cannot designate its own classwide type", S);
1323 -- Clean up indication of tagged status to prevent cascaded errors
1325 Set_Is_Tagged_Type (T, False);
1330 -- If the type has appeared already in a with_type clause, it is
1331 -- frozen and the pointer size is already set. Else, initialize.
1333 if not From_With_Type (T) then
1334 Init_Size_Align (T);
1337 -- Note that Has_Task is always false, since the access type itself
1338 -- is not a task type. See Einfo for more description on this point.
1339 -- Exactly the same consideration applies to Has_Controlled_Component.
1341 Set_Has_Task (T, False);
1342 Set_Has_Controlled_Component (T, False);
1344 -- Initialize Associated_Final_Chain explicitly to Empty, to avoid
1345 -- problems where an incomplete view of this entity has been previously
1346 -- established by a limited with and an overlaid version of this field
1347 -- (Stored_Constraint) was initialized for the incomplete view.
1349 Set_Associated_Final_Chain (T, Empty);
1351 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1354 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1355 Set_Is_Access_Constant (T, Constant_Present (Def));
1356 end Access_Type_Declaration;
1358 ----------------------------------
1359 -- Add_Interface_Tag_Components --
1360 ----------------------------------
1362 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1363 Loc : constant Source_Ptr := Sloc (N);
1367 procedure Add_Tag (Iface : Entity_Id);
1368 -- Add tag for one of the progenitor interfaces
1374 procedure Add_Tag (Iface : Entity_Id) is
1381 pragma Assert (Is_Tagged_Type (Iface)
1382 and then Is_Interface (Iface));
1384 -- This is a reasonable place to propagate predicates
1386 if Has_Predicates (Iface) then
1387 Set_Has_Predicates (Typ);
1391 Make_Component_Definition (Loc,
1392 Aliased_Present => True,
1393 Subtype_Indication =>
1394 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1396 Tag := Make_Temporary (Loc, 'V');
1399 Make_Component_Declaration (Loc,
1400 Defining_Identifier => Tag,
1401 Component_Definition => Def);
1403 Analyze_Component_Declaration (Decl);
1405 Set_Analyzed (Decl);
1406 Set_Ekind (Tag, E_Component);
1408 Set_Is_Aliased (Tag);
1409 Set_Related_Type (Tag, Iface);
1410 Init_Component_Location (Tag);
1412 pragma Assert (Is_Frozen (Iface));
1414 Set_DT_Entry_Count (Tag,
1415 DT_Entry_Count (First_Entity (Iface)));
1417 if No (Last_Tag) then
1420 Insert_After (Last_Tag, Decl);
1425 -- If the ancestor has discriminants we need to give special support
1426 -- to store the offset_to_top value of the secondary dispatch tables.
1427 -- For this purpose we add a supplementary component just after the
1428 -- field that contains the tag associated with each secondary DT.
1430 if Typ /= Etype (Typ)
1431 and then Has_Discriminants (Etype (Typ))
1434 Make_Component_Definition (Loc,
1435 Subtype_Indication =>
1436 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1438 Offset := Make_Temporary (Loc, 'V');
1441 Make_Component_Declaration (Loc,
1442 Defining_Identifier => Offset,
1443 Component_Definition => Def);
1445 Analyze_Component_Declaration (Decl);
1447 Set_Analyzed (Decl);
1448 Set_Ekind (Offset, E_Component);
1449 Set_Is_Aliased (Offset);
1450 Set_Related_Type (Offset, Iface);
1451 Init_Component_Location (Offset);
1452 Insert_After (Last_Tag, Decl);
1463 -- Start of processing for Add_Interface_Tag_Components
1466 if not RTE_Available (RE_Interface_Tag) then
1468 ("(Ada 2005) interface types not supported by this run-time!",
1473 if Ekind (Typ) /= E_Record_Type
1474 or else (Is_Concurrent_Record_Type (Typ)
1475 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1476 or else (not Is_Concurrent_Record_Type (Typ)
1477 and then No (Interfaces (Typ))
1478 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1483 -- Find the current last tag
1485 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1486 Ext := Record_Extension_Part (Type_Definition (N));
1488 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1489 Ext := Type_Definition (N);
1494 if not (Present (Component_List (Ext))) then
1495 Set_Null_Present (Ext, False);
1497 Set_Component_List (Ext,
1498 Make_Component_List (Loc,
1499 Component_Items => L,
1500 Null_Present => False));
1502 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1503 L := Component_Items
1505 (Record_Extension_Part
1506 (Type_Definition (N))));
1508 L := Component_Items
1510 (Type_Definition (N)));
1513 -- Find the last tag component
1516 while Present (Comp) loop
1517 if Nkind (Comp) = N_Component_Declaration
1518 and then Is_Tag (Defining_Identifier (Comp))
1527 -- At this point L references the list of components and Last_Tag
1528 -- references the current last tag (if any). Now we add the tag
1529 -- corresponding with all the interfaces that are not implemented
1532 if Present (Interfaces (Typ)) then
1533 Elmt := First_Elmt (Interfaces (Typ));
1534 while Present (Elmt) loop
1535 Add_Tag (Node (Elmt));
1539 end Add_Interface_Tag_Components;
1541 -------------------------------------
1542 -- Add_Internal_Interface_Entities --
1543 -------------------------------------
1545 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1548 Iface_Elmt : Elmt_Id;
1549 Iface_Prim : Entity_Id;
1550 Ifaces_List : Elist_Id;
1551 New_Subp : Entity_Id := Empty;
1553 Restore_Scope : Boolean := False;
1556 pragma Assert (Ada_Version >= Ada_2005
1557 and then Is_Record_Type (Tagged_Type)
1558 and then Is_Tagged_Type (Tagged_Type)
1559 and then Has_Interfaces (Tagged_Type)
1560 and then not Is_Interface (Tagged_Type));
1562 -- Ensure that the internal entities are added to the scope of the type
1564 if Scope (Tagged_Type) /= Current_Scope then
1565 Push_Scope (Scope (Tagged_Type));
1566 Restore_Scope := True;
1569 Collect_Interfaces (Tagged_Type, Ifaces_List);
1571 Iface_Elmt := First_Elmt (Ifaces_List);
1572 while Present (Iface_Elmt) loop
1573 Iface := Node (Iface_Elmt);
1575 -- Originally we excluded here from this processing interfaces that
1576 -- are parents of Tagged_Type because their primitives are located
1577 -- in the primary dispatch table (and hence no auxiliary internal
1578 -- entities are required to handle secondary dispatch tables in such
1579 -- case). However, these auxiliary entities are also required to
1580 -- handle derivations of interfaces in formals of generics (see
1581 -- Derive_Subprograms).
1583 Elmt := First_Elmt (Primitive_Operations (Iface));
1584 while Present (Elmt) loop
1585 Iface_Prim := Node (Elmt);
1587 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1589 Find_Primitive_Covering_Interface
1590 (Tagged_Type => Tagged_Type,
1591 Iface_Prim => Iface_Prim);
1593 pragma Assert (Present (Prim));
1595 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1596 -- differs from the name of the interface primitive then it is
1597 -- a private primitive inherited from a parent type. In such
1598 -- case, given that Tagged_Type covers the interface, the
1599 -- inherited private primitive becomes visible. For such
1600 -- purpose we add a new entity that renames the inherited
1601 -- private primitive.
1603 if Chars (Prim) /= Chars (Iface_Prim) then
1604 pragma Assert (Has_Suffix (Prim, 'P'));
1606 (New_Subp => New_Subp,
1607 Parent_Subp => Iface_Prim,
1608 Derived_Type => Tagged_Type,
1609 Parent_Type => Iface);
1610 Set_Alias (New_Subp, Prim);
1611 Set_Is_Abstract_Subprogram
1612 (New_Subp, Is_Abstract_Subprogram (Prim));
1616 (New_Subp => New_Subp,
1617 Parent_Subp => Iface_Prim,
1618 Derived_Type => Tagged_Type,
1619 Parent_Type => Iface);
1621 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1622 -- associated with interface types. These entities are
1623 -- only registered in the list of primitives of its
1624 -- corresponding tagged type because they are only used
1625 -- to fill the contents of the secondary dispatch tables.
1626 -- Therefore they are removed from the homonym chains.
1628 Set_Is_Hidden (New_Subp);
1629 Set_Is_Internal (New_Subp);
1630 Set_Alias (New_Subp, Prim);
1631 Set_Is_Abstract_Subprogram
1632 (New_Subp, Is_Abstract_Subprogram (Prim));
1633 Set_Interface_Alias (New_Subp, Iface_Prim);
1635 -- Internal entities associated with interface types are
1636 -- only registered in the list of primitives of the tagged
1637 -- type. They are only used to fill the contents of the
1638 -- secondary dispatch tables. Therefore they are not needed
1639 -- in the homonym chains.
1641 Remove_Homonym (New_Subp);
1643 -- Hidden entities associated with interfaces must have set
1644 -- the Has_Delay_Freeze attribute to ensure that, in case of
1645 -- locally defined tagged types (or compiling with static
1646 -- dispatch tables generation disabled) the corresponding
1647 -- entry of the secondary dispatch table is filled when
1648 -- such an entity is frozen.
1650 Set_Has_Delayed_Freeze (New_Subp);
1656 Next_Elmt (Iface_Elmt);
1659 if Restore_Scope then
1662 end Add_Internal_Interface_Entities;
1664 -----------------------------------
1665 -- Analyze_Component_Declaration --
1666 -----------------------------------
1668 procedure Analyze_Component_Declaration (N : Node_Id) is
1669 Id : constant Entity_Id := Defining_Identifier (N);
1670 E : constant Node_Id := Expression (N);
1671 Typ : constant Node_Id :=
1672 Subtype_Indication (Component_Definition (N));
1676 function Contains_POC (Constr : Node_Id) return Boolean;
1677 -- Determines whether a constraint uses the discriminant of a record
1678 -- type thus becoming a per-object constraint (POC).
1680 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1681 -- Typ is the type of the current component, check whether this type is
1682 -- a limited type. Used to validate declaration against that of
1683 -- enclosing record.
1689 function Contains_POC (Constr : Node_Id) return Boolean is
1691 -- Prevent cascaded errors
1693 if Error_Posted (Constr) then
1697 case Nkind (Constr) is
1698 when N_Attribute_Reference =>
1700 Attribute_Name (Constr) = Name_Access
1701 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1703 when N_Discriminant_Association =>
1704 return Denotes_Discriminant (Expression (Constr));
1706 when N_Identifier =>
1707 return Denotes_Discriminant (Constr);
1709 when N_Index_Or_Discriminant_Constraint =>
1714 IDC := First (Constraints (Constr));
1715 while Present (IDC) loop
1717 -- One per-object constraint is sufficient
1719 if Contains_POC (IDC) then
1730 return Denotes_Discriminant (Low_Bound (Constr))
1732 Denotes_Discriminant (High_Bound (Constr));
1734 when N_Range_Constraint =>
1735 return Denotes_Discriminant (Range_Expression (Constr));
1743 ----------------------
1744 -- Is_Known_Limited --
1745 ----------------------
1747 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1748 P : constant Entity_Id := Etype (Typ);
1749 R : constant Entity_Id := Root_Type (Typ);
1752 if Is_Limited_Record (Typ) then
1755 -- If the root type is limited (and not a limited interface)
1756 -- so is the current type
1758 elsif Is_Limited_Record (R)
1760 (not Is_Interface (R)
1761 or else not Is_Limited_Interface (R))
1765 -- Else the type may have a limited interface progenitor, but a
1766 -- limited record parent.
1769 and then Is_Limited_Record (P)
1776 end Is_Known_Limited;
1778 -- Start of processing for Analyze_Component_Declaration
1781 Generate_Definition (Id);
1784 if Present (Typ) then
1785 T := Find_Type_Of_Object
1786 (Subtype_Indication (Component_Definition (N)), N);
1788 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1789 Check_SPARK_Restriction ("subtype mark required", Typ);
1792 -- Ada 2005 (AI-230): Access Definition case
1795 pragma Assert (Present
1796 (Access_Definition (Component_Definition (N))));
1798 T := Access_Definition
1800 N => Access_Definition (Component_Definition (N)));
1801 Set_Is_Local_Anonymous_Access (T);
1803 -- Ada 2005 (AI-254)
1805 if Present (Access_To_Subprogram_Definition
1806 (Access_Definition (Component_Definition (N))))
1807 and then Protected_Present (Access_To_Subprogram_Definition
1809 (Component_Definition (N))))
1811 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1815 -- If the subtype is a constrained subtype of the enclosing record,
1816 -- (which must have a partial view) the back-end does not properly
1817 -- handle the recursion. Rewrite the component declaration with an
1818 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1819 -- the tree directly because side effects have already been removed from
1820 -- discriminant constraints.
1822 if Ekind (T) = E_Access_Subtype
1823 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1824 and then Comes_From_Source (T)
1825 and then Nkind (Parent (T)) = N_Subtype_Declaration
1826 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1829 (Subtype_Indication (Component_Definition (N)),
1830 New_Copy_Tree (Subtype_Indication (Parent (T))));
1831 T := Find_Type_Of_Object
1832 (Subtype_Indication (Component_Definition (N)), N);
1835 -- If the component declaration includes a default expression, then we
1836 -- check that the component is not of a limited type (RM 3.7(5)),
1837 -- and do the special preanalysis of the expression (see section on
1838 -- "Handling of Default and Per-Object Expressions" in the spec of
1842 Check_SPARK_Restriction ("default expression is not allowed", E);
1843 Preanalyze_Spec_Expression (E, T);
1844 Check_Initialization (T, E);
1846 if Ada_Version >= Ada_2005
1847 and then Ekind (T) = E_Anonymous_Access_Type
1848 and then Etype (E) /= Any_Type
1850 -- Check RM 3.9.2(9): "if the expected type for an expression is
1851 -- an anonymous access-to-specific tagged type, then the object
1852 -- designated by the expression shall not be dynamically tagged
1853 -- unless it is a controlling operand in a call on a dispatching
1856 if Is_Tagged_Type (Directly_Designated_Type (T))
1858 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1860 Ekind (Directly_Designated_Type (Etype (E))) =
1864 ("access to specific tagged type required (RM 3.9.2(9))", E);
1867 -- (Ada 2005: AI-230): Accessibility check for anonymous
1870 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1872 ("expression has deeper access level than component " &
1873 "(RM 3.10.2 (12.2))", E);
1876 -- The initialization expression is a reference to an access
1877 -- discriminant. The type of the discriminant is always deeper
1878 -- than any access type.
1880 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1881 and then Is_Entity_Name (E)
1882 and then Ekind (Entity (E)) = E_In_Parameter
1883 and then Present (Discriminal_Link (Entity (E)))
1886 ("discriminant has deeper accessibility level than target",
1892 -- The parent type may be a private view with unknown discriminants,
1893 -- and thus unconstrained. Regular components must be constrained.
1895 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1896 if Is_Class_Wide_Type (T) then
1898 ("class-wide subtype with unknown discriminants" &
1899 " in component declaration",
1900 Subtype_Indication (Component_Definition (N)));
1903 ("unconstrained subtype in component declaration",
1904 Subtype_Indication (Component_Definition (N)));
1907 -- Components cannot be abstract, except for the special case of
1908 -- the _Parent field (case of extending an abstract tagged type)
1910 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1911 Error_Msg_N ("type of a component cannot be abstract", N);
1915 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1917 -- The component declaration may have a per-object constraint, set
1918 -- the appropriate flag in the defining identifier of the subtype.
1920 if Present (Subtype_Indication (Component_Definition (N))) then
1922 Sindic : constant Node_Id :=
1923 Subtype_Indication (Component_Definition (N));
1925 if Nkind (Sindic) = N_Subtype_Indication
1926 and then Present (Constraint (Sindic))
1927 and then Contains_POC (Constraint (Sindic))
1929 Set_Has_Per_Object_Constraint (Id);
1934 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1935 -- out some static checks.
1937 if Ada_Version >= Ada_2005
1938 and then Can_Never_Be_Null (T)
1940 Null_Exclusion_Static_Checks (N);
1943 -- If this component is private (or depends on a private type), flag the
1944 -- record type to indicate that some operations are not available.
1946 P := Private_Component (T);
1950 -- Check for circular definitions
1952 if P = Any_Type then
1953 Set_Etype (Id, Any_Type);
1955 -- There is a gap in the visibility of operations only if the
1956 -- component type is not defined in the scope of the record type.
1958 elsif Scope (P) = Scope (Current_Scope) then
1961 elsif Is_Limited_Type (P) then
1962 Set_Is_Limited_Composite (Current_Scope);
1965 Set_Is_Private_Composite (Current_Scope);
1970 and then Is_Limited_Type (T)
1971 and then Chars (Id) /= Name_uParent
1972 and then Is_Tagged_Type (Current_Scope)
1974 if Is_Derived_Type (Current_Scope)
1975 and then not Is_Known_Limited (Current_Scope)
1978 ("extension of nonlimited type cannot have limited components",
1981 if Is_Interface (Root_Type (Current_Scope)) then
1983 ("\limitedness is not inherited from limited interface", N);
1984 Error_Msg_N ("\add LIMITED to type indication", N);
1987 Explain_Limited_Type (T, N);
1988 Set_Etype (Id, Any_Type);
1989 Set_Is_Limited_Composite (Current_Scope, False);
1991 elsif not Is_Derived_Type (Current_Scope)
1992 and then not Is_Limited_Record (Current_Scope)
1993 and then not Is_Concurrent_Type (Current_Scope)
1996 ("nonlimited tagged type cannot have limited components", N);
1997 Explain_Limited_Type (T, N);
1998 Set_Etype (Id, Any_Type);
1999 Set_Is_Limited_Composite (Current_Scope, False);
2003 Set_Original_Record_Component (Id, Id);
2005 if Has_Aspects (N) then
2006 Analyze_Aspect_Specifications (N, Id);
2008 end Analyze_Component_Declaration;
2010 --------------------------
2011 -- Analyze_Declarations --
2012 --------------------------
2014 procedure Analyze_Declarations (L : List_Id) is
2016 Freeze_From : Entity_Id := Empty;
2017 Next_Node : Node_Id;
2020 -- Adjust D not to include implicit label declarations, since these
2021 -- have strange Sloc values that result in elaboration check problems.
2022 -- (They have the sloc of the label as found in the source, and that
2023 -- is ahead of the current declarative part).
2029 procedure Adjust_D is
2031 while Present (Prev (D))
2032 and then Nkind (D) = N_Implicit_Label_Declaration
2038 -- Start of processing for Analyze_Declarations
2041 if SPARK_Mode or else Restriction_Check_Required (SPARK) then
2042 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2046 while Present (D) loop
2048 -- Package specification cannot contain a package declaration in
2051 if Nkind (D) = N_Package_Declaration
2052 and then Nkind (Parent (L)) = N_Package_Specification
2054 Check_SPARK_Restriction ("package specification cannot contain "
2055 & "a package declaration", D);
2058 -- Complete analysis of declaration
2061 Next_Node := Next (D);
2063 if No (Freeze_From) then
2064 Freeze_From := First_Entity (Current_Scope);
2067 -- At the end of a declarative part, freeze remaining entities
2068 -- declared in it. The end of the visible declarations of package
2069 -- specification is not the end of a declarative part if private
2070 -- declarations are present. The end of a package declaration is a
2071 -- freezing point only if it a library package. A task definition or
2072 -- protected type definition is not a freeze point either. Finally,
2073 -- we do not freeze entities in generic scopes, because there is no
2074 -- code generated for them and freeze nodes will be generated for
2077 -- The end of a package instantiation is not a freeze point, but
2078 -- for now we make it one, because the generic body is inserted
2079 -- (currently) immediately after. Generic instantiations will not
2080 -- be a freeze point once delayed freezing of bodies is implemented.
2081 -- (This is needed in any case for early instantiations ???).
2083 if No (Next_Node) then
2084 if Nkind_In (Parent (L), N_Component_List,
2086 N_Protected_Definition)
2090 elsif Nkind (Parent (L)) /= N_Package_Specification then
2091 if Nkind (Parent (L)) = N_Package_Body then
2092 Freeze_From := First_Entity (Current_Scope);
2096 Freeze_All (Freeze_From, D);
2097 Freeze_From := Last_Entity (Current_Scope);
2099 elsif Scope (Current_Scope) /= Standard_Standard
2100 and then not Is_Child_Unit (Current_Scope)
2101 and then No (Generic_Parent (Parent (L)))
2105 elsif L /= Visible_Declarations (Parent (L))
2106 or else No (Private_Declarations (Parent (L)))
2107 or else Is_Empty_List (Private_Declarations (Parent (L)))
2110 Freeze_All (Freeze_From, D);
2111 Freeze_From := Last_Entity (Current_Scope);
2114 -- If next node is a body then freeze all types before the body.
2115 -- An exception occurs for some expander-generated bodies. If these
2116 -- are generated at places where in general language rules would not
2117 -- allow a freeze point, then we assume that the expander has
2118 -- explicitly checked that all required types are properly frozen,
2119 -- and we do not cause general freezing here. This special circuit
2120 -- is used when the encountered body is marked as having already
2123 -- In all other cases (bodies that come from source, and expander
2124 -- generated bodies that have not been analyzed yet), freeze all
2125 -- types now. Note that in the latter case, the expander must take
2126 -- care to attach the bodies at a proper place in the tree so as to
2127 -- not cause unwanted freezing at that point.
2129 elsif not Analyzed (Next_Node)
2130 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2136 Nkind (Next_Node) in N_Body_Stub)
2139 Freeze_All (Freeze_From, D);
2140 Freeze_From := Last_Entity (Current_Scope);
2146 -- One more thing to do, we need to scan the declarations to check
2147 -- for any precondition/postcondition pragmas (Pre/Post aspects have
2148 -- by this stage been converted into corresponding pragmas). It is
2149 -- at this point that we analyze the expressions in such pragmas,
2150 -- to implement the delayed visibility requirement.
2160 while Present (Decl) loop
2161 if Nkind (Original_Node (Decl)) = N_Subprogram_Declaration then
2162 Spec := Specification (Original_Node (Decl));
2163 Sent := Defining_Unit_Name (Spec);
2164 Prag := Spec_PPC_List (Sent);
2165 while Present (Prag) loop
2166 Analyze_PPC_In_Decl_Part (Prag, Sent);
2167 Prag := Next_Pragma (Prag);
2174 end Analyze_Declarations;
2176 -----------------------------------
2177 -- Analyze_Full_Type_Declaration --
2178 -----------------------------------
2180 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2181 Def : constant Node_Id := Type_Definition (N);
2182 Def_Id : constant Entity_Id := Defining_Identifier (N);
2186 Is_Remote : constant Boolean :=
2187 (Is_Remote_Types (Current_Scope)
2188 or else Is_Remote_Call_Interface (Current_Scope))
2189 and then not (In_Private_Part (Current_Scope)
2190 or else In_Package_Body (Current_Scope));
2192 procedure Check_Ops_From_Incomplete_Type;
2193 -- If there is a tagged incomplete partial view of the type, traverse
2194 -- the primitives of the incomplete view and change the type of any
2195 -- controlling formals and result to indicate the full view. The
2196 -- primitives will be added to the full type's primitive operations
2197 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2198 -- is called from Process_Incomplete_Dependents).
2200 ------------------------------------
2201 -- Check_Ops_From_Incomplete_Type --
2202 ------------------------------------
2204 procedure Check_Ops_From_Incomplete_Type is
2211 and then Ekind (Prev) = E_Incomplete_Type
2212 and then Is_Tagged_Type (Prev)
2213 and then Is_Tagged_Type (T)
2215 Elmt := First_Elmt (Primitive_Operations (Prev));
2216 while Present (Elmt) loop
2219 Formal := First_Formal (Op);
2220 while Present (Formal) loop
2221 if Etype (Formal) = Prev then
2222 Set_Etype (Formal, T);
2225 Next_Formal (Formal);
2228 if Etype (Op) = Prev then
2235 end Check_Ops_From_Incomplete_Type;
2237 -- Start of processing for Analyze_Full_Type_Declaration
2240 Prev := Find_Type_Name (N);
2242 -- The full view, if present, now points to the current type
2244 -- Ada 2005 (AI-50217): If the type was previously decorated when
2245 -- imported through a LIMITED WITH clause, it appears as incomplete
2246 -- but has no full view.
2248 if Ekind (Prev) = E_Incomplete_Type
2249 and then Present (Full_View (Prev))
2251 T := Full_View (Prev);
2256 Set_Is_Pure (T, Is_Pure (Current_Scope));
2258 -- We set the flag Is_First_Subtype here. It is needed to set the
2259 -- corresponding flag for the Implicit class-wide-type created
2260 -- during tagged types processing.
2262 Set_Is_First_Subtype (T, True);
2264 -- Only composite types other than array types are allowed to have
2269 -- For derived types, the rule will be checked once we've figured
2270 -- out the parent type.
2272 when N_Derived_Type_Definition =>
2275 -- For record types, discriminants are allowed, unless we are in
2278 when N_Record_Definition =>
2279 if Present (Discriminant_Specifications (N)) then
2280 Check_SPARK_Restriction
2281 ("discriminant type is not allowed",
2283 (First (Discriminant_Specifications (N))));
2287 if Present (Discriminant_Specifications (N)) then
2289 ("elementary or array type cannot have discriminants",
2291 (First (Discriminant_Specifications (N))));
2295 -- Elaborate the type definition according to kind, and generate
2296 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2297 -- already done (this happens during the reanalysis that follows a call
2298 -- to the high level optimizer).
2300 if not Analyzed (T) then
2305 when N_Access_To_Subprogram_Definition =>
2306 Access_Subprogram_Declaration (T, Def);
2308 -- If this is a remote access to subprogram, we must create the
2309 -- equivalent fat pointer type, and related subprograms.
2312 Process_Remote_AST_Declaration (N);
2315 -- Validate categorization rule against access type declaration
2316 -- usually a violation in Pure unit, Shared_Passive unit.
2318 Validate_Access_Type_Declaration (T, N);
2320 when N_Access_To_Object_Definition =>
2321 Access_Type_Declaration (T, Def);
2323 -- Validate categorization rule against access type declaration
2324 -- usually a violation in Pure unit, Shared_Passive unit.
2326 Validate_Access_Type_Declaration (T, N);
2328 -- If we are in a Remote_Call_Interface package and define a
2329 -- RACW, then calling stubs and specific stream attributes
2333 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2335 Add_RACW_Features (Def_Id);
2338 -- Set no strict aliasing flag if config pragma seen
2340 if Opt.No_Strict_Aliasing then
2341 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2344 when N_Array_Type_Definition =>
2345 Array_Type_Declaration (T, Def);
2347 when N_Derived_Type_Definition =>
2348 Derived_Type_Declaration (T, N, T /= Def_Id);
2350 when N_Enumeration_Type_Definition =>
2351 Enumeration_Type_Declaration (T, Def);
2353 when N_Floating_Point_Definition =>
2354 Floating_Point_Type_Declaration (T, Def);
2356 when N_Decimal_Fixed_Point_Definition =>
2357 Decimal_Fixed_Point_Type_Declaration (T, Def);
2359 when N_Ordinary_Fixed_Point_Definition =>
2360 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2362 when N_Signed_Integer_Type_Definition =>
2363 Signed_Integer_Type_Declaration (T, Def);
2365 when N_Modular_Type_Definition =>
2366 Modular_Type_Declaration (T, Def);
2368 when N_Record_Definition =>
2369 Record_Type_Declaration (T, N, Prev);
2371 -- If declaration has a parse error, nothing to elaborate.
2377 raise Program_Error;
2382 if Etype (T) = Any_Type then
2386 -- Controlled type is not allowed in SPARK
2388 if Is_Visibly_Controlled (T) then
2389 Check_SPARK_Restriction ("controlled type is not allowed", N);
2392 -- Some common processing for all types
2394 Set_Depends_On_Private (T, Has_Private_Component (T));
2395 Check_Ops_From_Incomplete_Type;
2397 -- Both the declared entity, and its anonymous base type if one
2398 -- was created, need freeze nodes allocated.
2401 B : constant Entity_Id := Base_Type (T);
2404 -- In the case where the base type differs from the first subtype, we
2405 -- pre-allocate a freeze node, and set the proper link to the first
2406 -- subtype. Freeze_Entity will use this preallocated freeze node when
2407 -- it freezes the entity.
2409 -- This does not apply if the base type is a generic type, whose
2410 -- declaration is independent of the current derived definition.
2412 if B /= T and then not Is_Generic_Type (B) then
2413 Ensure_Freeze_Node (B);
2414 Set_First_Subtype_Link (Freeze_Node (B), T);
2417 -- A type that is imported through a limited_with clause cannot
2418 -- generate any code, and thus need not be frozen. However, an access
2419 -- type with an imported designated type needs a finalization list,
2420 -- which may be referenced in some other package that has non-limited
2421 -- visibility on the designated type. Thus we must create the
2422 -- finalization list at the point the access type is frozen, to
2423 -- prevent unsatisfied references at link time.
2425 if not From_With_Type (T) or else Is_Access_Type (T) then
2426 Set_Has_Delayed_Freeze (T);
2430 -- Case where T is the full declaration of some private type which has
2431 -- been swapped in Defining_Identifier (N).
2433 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2434 Process_Full_View (N, T, Def_Id);
2436 -- Record the reference. The form of this is a little strange, since
2437 -- the full declaration has been swapped in. So the first parameter
2438 -- here represents the entity to which a reference is made which is
2439 -- the "real" entity, i.e. the one swapped in, and the second
2440 -- parameter provides the reference location.
2442 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2443 -- since we don't want a complaint about the full type being an
2444 -- unwanted reference to the private type
2447 B : constant Boolean := Has_Pragma_Unreferenced (T);
2449 Set_Has_Pragma_Unreferenced (T, False);
2450 Generate_Reference (T, T, 'c');
2451 Set_Has_Pragma_Unreferenced (T, B);
2454 Set_Completion_Referenced (Def_Id);
2456 -- For completion of incomplete type, process incomplete dependents
2457 -- and always mark the full type as referenced (it is the incomplete
2458 -- type that we get for any real reference).
2460 elsif Ekind (Prev) = E_Incomplete_Type then
2461 Process_Incomplete_Dependents (N, T, Prev);
2462 Generate_Reference (Prev, Def_Id, 'c');
2463 Set_Completion_Referenced (Def_Id);
2465 -- If not private type or incomplete type completion, this is a real
2466 -- definition of a new entity, so record it.
2469 Generate_Definition (Def_Id);
2472 if Chars (Scope (Def_Id)) = Name_System
2473 and then Chars (Def_Id) = Name_Address
2474 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2476 Set_Is_Descendent_Of_Address (Def_Id);
2477 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2478 Set_Is_Descendent_Of_Address (Prev);
2481 Set_Optimize_Alignment_Flags (Def_Id);
2482 Check_Eliminated (Def_Id);
2484 if Has_Aspects (N) then
2485 Analyze_Aspect_Specifications (N, Def_Id);
2487 end Analyze_Full_Type_Declaration;
2489 ----------------------------------
2490 -- Analyze_Incomplete_Type_Decl --
2491 ----------------------------------
2493 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2494 F : constant Boolean := Is_Pure (Current_Scope);
2498 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2500 Generate_Definition (Defining_Identifier (N));
2502 -- Process an incomplete declaration. The identifier must not have been
2503 -- declared already in the scope. However, an incomplete declaration may
2504 -- appear in the private part of a package, for a private type that has
2505 -- already been declared.
2507 -- In this case, the discriminants (if any) must match
2509 T := Find_Type_Name (N);
2511 Set_Ekind (T, E_Incomplete_Type);
2512 Init_Size_Align (T);
2513 Set_Is_First_Subtype (T, True);
2516 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2517 -- incomplete types.
2519 if Tagged_Present (N) then
2520 Set_Is_Tagged_Type (T);
2521 Make_Class_Wide_Type (T);
2522 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2527 Set_Stored_Constraint (T, No_Elist);
2529 if Present (Discriminant_Specifications (N)) then
2530 Process_Discriminants (N);
2535 -- If the type has discriminants, non-trivial subtypes may be
2536 -- declared before the full view of the type. The full views of those
2537 -- subtypes will be built after the full view of the type.
2539 Set_Private_Dependents (T, New_Elmt_List);
2541 end Analyze_Incomplete_Type_Decl;
2543 -----------------------------------
2544 -- Analyze_Interface_Declaration --
2545 -----------------------------------
2547 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2548 CW : constant Entity_Id := Class_Wide_Type (T);
2551 Set_Is_Tagged_Type (T);
2553 Set_Is_Limited_Record (T, Limited_Present (Def)
2554 or else Task_Present (Def)
2555 or else Protected_Present (Def)
2556 or else Synchronized_Present (Def));
2558 -- Type is abstract if full declaration carries keyword, or if previous
2559 -- partial view did.
2561 Set_Is_Abstract_Type (T);
2562 Set_Is_Interface (T);
2564 -- Type is a limited interface if it includes the keyword limited, task,
2565 -- protected, or synchronized.
2567 Set_Is_Limited_Interface
2568 (T, Limited_Present (Def)
2569 or else Protected_Present (Def)
2570 or else Synchronized_Present (Def)
2571 or else Task_Present (Def));
2573 Set_Interfaces (T, New_Elmt_List);
2574 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2576 -- Complete the decoration of the class-wide entity if it was already
2577 -- built (i.e. during the creation of the limited view)
2579 if Present (CW) then
2580 Set_Is_Interface (CW);
2581 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2584 -- Check runtime support for synchronized interfaces
2586 if VM_Target = No_VM
2587 and then (Is_Task_Interface (T)
2588 or else Is_Protected_Interface (T)
2589 or else Is_Synchronized_Interface (T))
2590 and then not RTE_Available (RE_Select_Specific_Data)
2592 Error_Msg_CRT ("synchronized interfaces", T);
2594 end Analyze_Interface_Declaration;
2596 -----------------------------
2597 -- Analyze_Itype_Reference --
2598 -----------------------------
2600 -- Nothing to do. This node is placed in the tree only for the benefit of
2601 -- back end processing, and has no effect on the semantic processing.
2603 procedure Analyze_Itype_Reference (N : Node_Id) is
2605 pragma Assert (Is_Itype (Itype (N)));
2607 end Analyze_Itype_Reference;
2609 --------------------------------
2610 -- Analyze_Number_Declaration --
2611 --------------------------------
2613 procedure Analyze_Number_Declaration (N : Node_Id) is
2614 Id : constant Entity_Id := Defining_Identifier (N);
2615 E : constant Node_Id := Expression (N);
2617 Index : Interp_Index;
2621 Generate_Definition (Id);
2624 -- This is an optimization of a common case of an integer literal
2626 if Nkind (E) = N_Integer_Literal then
2627 Set_Is_Static_Expression (E, True);
2628 Set_Etype (E, Universal_Integer);
2630 Set_Etype (Id, Universal_Integer);
2631 Set_Ekind (Id, E_Named_Integer);
2632 Set_Is_Frozen (Id, True);
2636 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2638 -- Process expression, replacing error by integer zero, to avoid
2639 -- cascaded errors or aborts further along in the processing
2641 -- Replace Error by integer zero, which seems least likely to
2642 -- cause cascaded errors.
2645 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2646 Set_Error_Posted (E);
2651 -- Verify that the expression is static and numeric. If
2652 -- the expression is overloaded, we apply the preference
2653 -- rule that favors root numeric types.
2655 if not Is_Overloaded (E) then
2661 Get_First_Interp (E, Index, It);
2662 while Present (It.Typ) loop
2663 if (Is_Integer_Type (It.Typ)
2664 or else Is_Real_Type (It.Typ))
2665 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2667 if T = Any_Type then
2670 elsif It.Typ = Universal_Real
2671 or else It.Typ = Universal_Integer
2673 -- Choose universal interpretation over any other
2680 Get_Next_Interp (Index, It);
2684 if Is_Integer_Type (T) then
2686 Set_Etype (Id, Universal_Integer);
2687 Set_Ekind (Id, E_Named_Integer);
2689 elsif Is_Real_Type (T) then
2691 -- Because the real value is converted to universal_real, this is a
2692 -- legal context for a universal fixed expression.
2694 if T = Universal_Fixed then
2696 Loc : constant Source_Ptr := Sloc (N);
2697 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2699 New_Occurrence_Of (Universal_Real, Loc),
2700 Expression => Relocate_Node (E));
2707 elsif T = Any_Fixed then
2708 Error_Msg_N ("illegal context for mixed mode operation", E);
2710 -- Expression is of the form : universal_fixed * integer. Try to
2711 -- resolve as universal_real.
2713 T := Universal_Real;
2718 Set_Etype (Id, Universal_Real);
2719 Set_Ekind (Id, E_Named_Real);
2722 Wrong_Type (E, Any_Numeric);
2726 Set_Ekind (Id, E_Constant);
2727 Set_Never_Set_In_Source (Id, True);
2728 Set_Is_True_Constant (Id, True);
2732 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2733 Set_Etype (E, Etype (Id));
2736 if not Is_OK_Static_Expression (E) then
2737 Flag_Non_Static_Expr
2738 ("non-static expression used in number declaration!", E);
2739 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2740 Set_Etype (E, Any_Type);
2742 end Analyze_Number_Declaration;
2744 --------------------------------
2745 -- Analyze_Object_Declaration --
2746 --------------------------------
2748 procedure Analyze_Object_Declaration (N : Node_Id) is
2749 Loc : constant Source_Ptr := Sloc (N);
2750 Id : constant Entity_Id := Defining_Identifier (N);
2754 E : Node_Id := Expression (N);
2755 -- E is set to Expression (N) throughout this routine. When
2756 -- Expression (N) is modified, E is changed accordingly.
2758 Prev_Entity : Entity_Id := Empty;
2760 function Count_Tasks (T : Entity_Id) return Uint;
2761 -- This function is called when a non-generic library level object of a
2762 -- task type is declared. Its function is to count the static number of
2763 -- tasks declared within the type (it is only called if Has_Tasks is set
2764 -- for T). As a side effect, if an array of tasks with non-static bounds
2765 -- or a variant record type is encountered, Check_Restrictions is called
2766 -- indicating the count is unknown.
2772 function Count_Tasks (T : Entity_Id) return Uint is
2778 if Is_Task_Type (T) then
2781 elsif Is_Record_Type (T) then
2782 if Has_Discriminants (T) then
2783 Check_Restriction (Max_Tasks, N);
2788 C := First_Component (T);
2789 while Present (C) loop
2790 V := V + Count_Tasks (Etype (C));
2797 elsif Is_Array_Type (T) then
2798 X := First_Index (T);
2799 V := Count_Tasks (Component_Type (T));
2800 while Present (X) loop
2803 if not Is_Static_Subtype (C) then
2804 Check_Restriction (Max_Tasks, N);
2807 V := V * (UI_Max (Uint_0,
2808 Expr_Value (Type_High_Bound (C)) -
2809 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2822 -- Start of processing for Analyze_Object_Declaration
2825 -- There are three kinds of implicit types generated by an
2826 -- object declaration:
2828 -- 1. Those generated by the original Object Definition
2830 -- 2. Those generated by the Expression
2832 -- 3. Those used to constrained the Object Definition with the
2833 -- expression constraints when it is unconstrained
2835 -- They must be generated in this order to avoid order of elaboration
2836 -- issues. Thus the first step (after entering the name) is to analyze
2837 -- the object definition.
2839 if Constant_Present (N) then
2840 Prev_Entity := Current_Entity_In_Scope (Id);
2842 if Present (Prev_Entity)
2844 -- If the homograph is an implicit subprogram, it is overridden
2845 -- by the current declaration.
2847 ((Is_Overloadable (Prev_Entity)
2848 and then Is_Inherited_Operation (Prev_Entity))
2850 -- The current object is a discriminal generated for an entry
2851 -- family index. Even though the index is a constant, in this
2852 -- particular context there is no true constant redeclaration.
2853 -- Enter_Name will handle the visibility.
2856 (Is_Discriminal (Id)
2857 and then Ekind (Discriminal_Link (Id)) =
2858 E_Entry_Index_Parameter)
2860 -- The current object is the renaming for a generic declared
2861 -- within the instance.
2864 (Ekind (Prev_Entity) = E_Package
2865 and then Nkind (Parent (Prev_Entity)) =
2866 N_Package_Renaming_Declaration
2867 and then not Comes_From_Source (Prev_Entity)
2868 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2870 Prev_Entity := Empty;
2874 if Present (Prev_Entity) then
2875 Constant_Redeclaration (Id, N, T);
2877 Generate_Reference (Prev_Entity, Id, 'c');
2878 Set_Completion_Referenced (Id);
2880 if Error_Posted (N) then
2882 -- Type mismatch or illegal redeclaration, Do not analyze
2883 -- expression to avoid cascaded errors.
2885 T := Find_Type_Of_Object (Object_Definition (N), N);
2887 Set_Ekind (Id, E_Variable);
2891 -- In the normal case, enter identifier at the start to catch premature
2892 -- usage in the initialization expression.
2895 Generate_Definition (Id);
2898 Mark_Coextensions (N, Object_Definition (N));
2900 T := Find_Type_Of_Object (Object_Definition (N), N);
2902 if Nkind (Object_Definition (N)) = N_Access_Definition
2904 (Access_To_Subprogram_Definition (Object_Definition (N)))
2905 and then Protected_Present
2906 (Access_To_Subprogram_Definition (Object_Definition (N)))
2908 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2911 if Error_Posted (Id) then
2913 Set_Ekind (Id, E_Variable);
2918 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2919 -- out some static checks
2921 if Ada_Version >= Ada_2005
2922 and then Can_Never_Be_Null (T)
2924 -- In case of aggregates we must also take care of the correct
2925 -- initialization of nested aggregates bug this is done at the
2926 -- point of the analysis of the aggregate (see sem_aggr.adb)
2928 if Present (Expression (N))
2929 and then Nkind (Expression (N)) = N_Aggregate
2935 Save_Typ : constant Entity_Id := Etype (Id);
2937 Set_Etype (Id, T); -- Temp. decoration for static checks
2938 Null_Exclusion_Static_Checks (N);
2939 Set_Etype (Id, Save_Typ);
2944 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2946 -- If deferred constant, make sure context is appropriate. We detect
2947 -- a deferred constant as a constant declaration with no expression.
2948 -- A deferred constant can appear in a package body if its completion
2949 -- is by means of an interface pragma.
2951 if Constant_Present (N)
2954 -- A deferred constant may appear in the declarative part of the
2955 -- following constructs:
2959 -- extended return statements
2962 -- subprogram bodies
2965 -- When declared inside a package spec, a deferred constant must be
2966 -- completed by a full constant declaration or pragma Import. In all
2967 -- other cases, the only proper completion is pragma Import. Extended
2968 -- return statements are flagged as invalid contexts because they do
2969 -- not have a declarative part and so cannot accommodate the pragma.
2971 if Ekind (Current_Scope) = E_Return_Statement then
2973 ("invalid context for deferred constant declaration (RM 7.4)",
2976 ("\declaration requires an initialization expression",
2978 Set_Constant_Present (N, False);
2980 -- In Ada 83, deferred constant must be of private type
2982 elsif not Is_Private_Type (T) then
2983 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2985 ("(Ada 83) deferred constant must be private type", N);
2989 -- If not a deferred constant, then object declaration freezes its type
2992 Check_Fully_Declared (T, N);
2993 Freeze_Before (N, T);
2996 -- If the object was created by a constrained array definition, then
2997 -- set the link in both the anonymous base type and anonymous subtype
2998 -- that are built to represent the array type to point to the object.
3000 if Nkind (Object_Definition (Declaration_Node (Id))) =
3001 N_Constrained_Array_Definition
3003 Set_Related_Array_Object (T, Id);
3004 Set_Related_Array_Object (Base_Type (T), Id);
3007 -- Special checks for protected objects not at library level
3009 if Is_Protected_Type (T)
3010 and then not Is_Library_Level_Entity (Id)
3012 Check_Restriction (No_Local_Protected_Objects, Id);
3014 -- Protected objects with interrupt handlers must be at library level
3016 -- Ada 2005: this test is not needed (and the corresponding clause
3017 -- in the RM is removed) because accessibility checks are sufficient
3018 -- to make handlers not at the library level illegal.
3020 if Has_Interrupt_Handler (T)
3021 and then Ada_Version < Ada_2005
3024 ("interrupt object can only be declared at library level", Id);
3028 -- The actual subtype of the object is the nominal subtype, unless
3029 -- the nominal one is unconstrained and obtained from the expression.
3033 -- The object is in ALFA if-and-only-if its type is in ALFA and it is
3036 if Is_In_ALFA (T) and then not Aliased_Present (N) then
3037 Set_Is_In_ALFA (Id);
3039 Mark_Non_ALFA_Subprogram;
3042 -- These checks should be performed before the initialization expression
3043 -- is considered, so that the Object_Definition node is still the same
3044 -- as in source code.
3046 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3047 -- shall not be unconstrained. (The only exception to this is the
3048 -- admission of declarations of constants of type String.)
3051 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3053 Check_SPARK_Restriction
3054 ("subtype mark required", Object_Definition (N));
3056 elsif Is_Array_Type (T)
3057 and then not Is_Constrained (T)
3058 and then T /= Standard_String
3060 Check_SPARK_Restriction
3061 ("subtype mark of constrained type expected",
3062 Object_Definition (N));
3065 -- There are no aliased objects in SPARK
3067 if Aliased_Present (N) then
3068 Check_SPARK_Restriction ("aliased object is not allowed", N);
3071 -- Process initialization expression if present and not in error
3073 if Present (E) and then E /= Error then
3075 -- Generate an error in case of CPP class-wide object initialization.
3076 -- Required because otherwise the expansion of the class-wide
3077 -- assignment would try to use 'size to initialize the object
3078 -- (primitive that is not available in CPP tagged types).
3080 if Is_Class_Wide_Type (Act_T)
3082 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3084 (Present (Full_View (Root_Type (Etype (Act_T))))
3086 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3089 ("predefined assignment not available for 'C'P'P tagged types",
3093 Mark_Coextensions (N, E);
3096 -- In case of errors detected in the analysis of the expression,
3097 -- decorate it with the expected type to avoid cascaded errors
3099 if No (Etype (E)) then
3103 -- If an initialization expression is present, then we set the
3104 -- Is_True_Constant flag. It will be reset if this is a variable
3105 -- and it is indeed modified.
3107 Set_Is_True_Constant (Id, True);
3109 -- If we are analyzing a constant declaration, set its completion
3110 -- flag after analyzing and resolving the expression.
3112 if Constant_Present (N) then
3113 Set_Has_Completion (Id);
3116 -- Set type and resolve (type may be overridden later on)
3121 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3122 -- node (which was marked already-analyzed), we need to set the type
3123 -- to something other than Any_Access in order to keep gigi happy.
3125 if Etype (E) = Any_Access then
3129 -- If the object is an access to variable, the initialization
3130 -- expression cannot be an access to constant.
3132 if Is_Access_Type (T)
3133 and then not Is_Access_Constant (T)
3134 and then Is_Access_Type (Etype (E))
3135 and then Is_Access_Constant (Etype (E))
3138 ("access to variable cannot be initialized "
3139 & "with an access-to-constant expression", E);
3142 if not Assignment_OK (N) then
3143 Check_Initialization (T, E);
3146 Check_Unset_Reference (E);
3148 -- If this is a variable, then set current value. If this is a
3149 -- declared constant of a scalar type with a static expression,
3150 -- indicate that it is always valid.
3152 if not Constant_Present (N) then
3153 if Compile_Time_Known_Value (E) then
3154 Set_Current_Value (Id, E);
3157 elsif Is_Scalar_Type (T)
3158 and then Is_OK_Static_Expression (E)
3160 Set_Is_Known_Valid (Id);
3163 -- Deal with setting of null flags
3165 if Is_Access_Type (T) then
3166 if Known_Non_Null (E) then
3167 Set_Is_Known_Non_Null (Id, True);
3168 elsif Known_Null (E)
3169 and then not Can_Never_Be_Null (Id)
3171 Set_Is_Known_Null (Id, True);
3175 -- Check incorrect use of dynamically tagged expressions.
3177 if Is_Tagged_Type (T) then
3178 Check_Dynamically_Tagged_Expression
3184 Apply_Scalar_Range_Check (E, T);
3185 Apply_Static_Length_Check (E, T);
3187 if Nkind (Original_Node (N)) = N_Object_Declaration
3188 and then Comes_From_Source (Original_Node (N))
3190 -- Only call test if needed
3192 and then Restriction_Check_Required (SPARK)
3193 and then not Is_SPARK_Initialization_Expr (E)
3195 Check_SPARK_Restriction
3196 ("initialization expression is not appropriate", E);
3200 -- If the No_Streams restriction is set, check that the type of the
3201 -- object is not, and does not contain, any subtype derived from
3202 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3203 -- Has_Stream just for efficiency reasons. There is no point in
3204 -- spending time on a Has_Stream check if the restriction is not set.
3206 if Restriction_Check_Required (No_Streams) then
3207 if Has_Stream (T) then
3208 Check_Restriction (No_Streams, N);
3212 -- Deal with predicate check before we start to do major rewriting.
3213 -- it is OK to initialize and then check the initialized value, since
3214 -- the object goes out of scope if we get a predicate failure. Note
3215 -- that we do this in the analyzer and not the expander because the
3216 -- analyzer does some substantial rewriting in some cases.
3218 -- We need a predicate check if the type has predicates, and if either
3219 -- there is an initializing expression, or for default initialization
3220 -- when we have at least one case of an explicit default initial value.
3222 if not Suppress_Assignment_Checks (N)
3223 and then Present (Predicate_Function (T))
3227 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3230 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3233 -- Case of unconstrained type
3235 if Is_Indefinite_Subtype (T) then
3237 -- Nothing to do in deferred constant case
3239 if Constant_Present (N) and then No (E) then
3242 -- Case of no initialization present
3245 if No_Initialization (N) then
3248 elsif Is_Class_Wide_Type (T) then
3250 ("initialization required in class-wide declaration ", N);
3254 ("unconstrained subtype not allowed (need initialization)",
3255 Object_Definition (N));
3257 if Is_Record_Type (T) and then Has_Discriminants (T) then
3259 ("\provide initial value or explicit discriminant values",
3260 Object_Definition (N));
3263 ("\or give default discriminant values for type&",
3264 Object_Definition (N), T);
3266 elsif Is_Array_Type (T) then
3268 ("\provide initial value or explicit array bounds",
3269 Object_Definition (N));
3273 -- Case of initialization present but in error. Set initial
3274 -- expression as absent (but do not make above complaints)
3276 elsif E = Error then
3277 Set_Expression (N, Empty);
3280 -- Case of initialization present
3283 -- Not allowed in Ada 83
3285 if not Constant_Present (N) then
3286 if Ada_Version = Ada_83
3287 and then Comes_From_Source (Object_Definition (N))
3290 ("(Ada 83) unconstrained variable not allowed",
3291 Object_Definition (N));
3295 -- Now we constrain the variable from the initializing expression
3297 -- If the expression is an aggregate, it has been expanded into
3298 -- individual assignments. Retrieve the actual type from the
3299 -- expanded construct.
3301 if Is_Array_Type (T)
3302 and then No_Initialization (N)
3303 and then Nkind (Original_Node (E)) = N_Aggregate
3307 -- In case of class-wide interface object declarations we delay
3308 -- the generation of the equivalent record type declarations until
3309 -- its expansion because there are cases in they are not required.
3311 elsif Is_Interface (T) then
3315 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3316 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3319 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3321 if Aliased_Present (N) then
3322 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3325 Freeze_Before (N, Act_T);
3326 Freeze_Before (N, T);
3329 elsif Is_Array_Type (T)
3330 and then No_Initialization (N)
3331 and then Nkind (Original_Node (E)) = N_Aggregate
3333 if not Is_Entity_Name (Object_Definition (N)) then
3335 Check_Compile_Time_Size (Act_T);
3337 if Aliased_Present (N) then
3338 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3342 -- When the given object definition and the aggregate are specified
3343 -- independently, and their lengths might differ do a length check.
3344 -- This cannot happen if the aggregate is of the form (others =>...)
3346 if not Is_Constrained (T) then
3349 elsif Nkind (E) = N_Raise_Constraint_Error then
3351 -- Aggregate is statically illegal. Place back in declaration
3353 Set_Expression (N, E);
3354 Set_No_Initialization (N, False);
3356 elsif T = Etype (E) then
3359 elsif Nkind (E) = N_Aggregate
3360 and then Present (Component_Associations (E))
3361 and then Present (Choices (First (Component_Associations (E))))
3362 and then Nkind (First
3363 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3368 Apply_Length_Check (E, T);
3371 -- If the type is limited unconstrained with defaulted discriminants and
3372 -- there is no expression, then the object is constrained by the
3373 -- defaults, so it is worthwhile building the corresponding subtype.
3375 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3376 and then not Is_Constrained (T)
3377 and then Has_Discriminants (T)
3380 Act_T := Build_Default_Subtype (T, N);
3382 -- Ada 2005: a limited object may be initialized by means of an
3383 -- aggregate. If the type has default discriminants it has an
3384 -- unconstrained nominal type, Its actual subtype will be obtained
3385 -- from the aggregate, and not from the default discriminants.
3390 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3392 elsif Present (Underlying_Type (T))
3393 and then not Is_Constrained (Underlying_Type (T))
3394 and then Has_Discriminants (Underlying_Type (T))
3395 and then Nkind (E) = N_Function_Call
3396 and then Constant_Present (N)
3398 -- The back-end has problems with constants of a discriminated type
3399 -- with defaults, if the initial value is a function call. We
3400 -- generate an intermediate temporary for the result of the call.
3401 -- It is unclear why this should make it acceptable to gcc. ???
3403 Remove_Side_Effects (E);
3405 -- If this is a constant declaration of an unconstrained type and
3406 -- the initialization is an aggregate, we can use the subtype of the
3407 -- aggregate for the declared entity because it is immutable.
3409 elsif not Is_Constrained (T)
3410 and then Has_Discriminants (T)
3411 and then Constant_Present (N)
3412 and then not Has_Unchecked_Union (T)
3413 and then Nkind (E) = N_Aggregate
3418 -- Check No_Wide_Characters restriction
3420 Check_Wide_Character_Restriction (T, Object_Definition (N));
3422 -- Indicate this is not set in source. Certainly true for constants, and
3423 -- true for variables so far (will be reset for a variable if and when
3424 -- we encounter a modification in the source).
3426 Set_Never_Set_In_Source (Id, True);
3428 -- Now establish the proper kind and type of the object
3430 if Constant_Present (N) then
3431 Set_Ekind (Id, E_Constant);
3432 Set_Is_True_Constant (Id, True);
3435 Set_Ekind (Id, E_Variable);
3437 -- A variable is set as shared passive if it appears in a shared
3438 -- passive package, and is at the outer level. This is not done for
3439 -- entities generated during expansion, because those are always
3440 -- manipulated locally.
3442 if Is_Shared_Passive (Current_Scope)
3443 and then Is_Library_Level_Entity (Id)
3444 and then Comes_From_Source (Id)
3446 Set_Is_Shared_Passive (Id);
3447 Check_Shared_Var (Id, T, N);
3450 -- Set Has_Initial_Value if initializing expression present. Note
3451 -- that if there is no initializing expression, we leave the state
3452 -- of this flag unchanged (usually it will be False, but notably in
3453 -- the case of exception choice variables, it will already be true).
3456 Set_Has_Initial_Value (Id, True);
3460 -- Initialize alignment and size and capture alignment setting
3462 Init_Alignment (Id);
3464 Set_Optimize_Alignment_Flags (Id);
3466 -- Deal with aliased case
3468 if Aliased_Present (N) then
3469 Set_Is_Aliased (Id);
3471 -- If the object is aliased and the type is unconstrained with
3472 -- defaulted discriminants and there is no expression, then the
3473 -- object is constrained by the defaults, so it is worthwhile
3474 -- building the corresponding subtype.
3476 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3477 -- unconstrained, then only establish an actual subtype if the
3478 -- nominal subtype is indefinite. In definite cases the object is
3479 -- unconstrained in Ada 2005.
3482 and then Is_Record_Type (T)
3483 and then not Is_Constrained (T)
3484 and then Has_Discriminants (T)
3485 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3487 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3491 -- Now we can set the type of the object
3493 Set_Etype (Id, Act_T);
3495 -- Deal with controlled types
3497 if Has_Controlled_Component (Etype (Id))
3498 or else Is_Controlled (Etype (Id))
3500 if not Is_Library_Level_Entity (Id) then
3501 Check_Restriction (No_Nested_Finalization, N);
3503 Validate_Controlled_Object (Id);
3506 -- Generate a warning when an initialization causes an obvious ABE
3507 -- violation. If the init expression is a simple aggregate there
3508 -- shouldn't be any initialize/adjust call generated. This will be
3509 -- true as soon as aggregates are built in place when possible.
3511 -- ??? at the moment we do not generate warnings for temporaries
3512 -- created for those aggregates although Program_Error might be
3513 -- generated if compiled with -gnato.
3515 if Is_Controlled (Etype (Id))
3516 and then Comes_From_Source (Id)
3519 BT : constant Entity_Id := Base_Type (Etype (Id));
3521 Implicit_Call : Entity_Id;
3522 pragma Warnings (Off, Implicit_Call);
3523 -- ??? what is this for (never referenced!)
3525 function Is_Aggr (N : Node_Id) return Boolean;
3526 -- Check that N is an aggregate
3532 function Is_Aggr (N : Node_Id) return Boolean is
3534 case Nkind (Original_Node (N)) is
3535 when N_Aggregate | N_Extension_Aggregate =>
3538 when N_Qualified_Expression |
3540 N_Unchecked_Type_Conversion =>
3541 return Is_Aggr (Expression (Original_Node (N)));
3549 -- If no underlying type, we already are in an error situation.
3550 -- Do not try to add a warning since we do not have access to
3553 if No (Underlying_Type (BT)) then
3554 Implicit_Call := Empty;
3556 -- A generic type does not have usable primitive operators.
3557 -- Initialization calls are built for instances.
3559 elsif Is_Generic_Type (BT) then
3560 Implicit_Call := Empty;
3562 -- If the init expression is not an aggregate, an adjust call
3563 -- will be generated
3565 elsif Present (E) and then not Is_Aggr (E) then
3566 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3568 -- If no init expression and we are not in the deferred
3569 -- constant case, an Initialize call will be generated
3571 elsif No (E) and then not Constant_Present (N) then
3572 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3575 Implicit_Call := Empty;
3581 if Has_Task (Etype (Id)) then
3582 Check_Restriction (No_Tasking, N);
3584 -- Deal with counting max tasks
3586 -- Nothing to do if inside a generic
3588 if Inside_A_Generic then
3591 -- If library level entity, then count tasks
3593 elsif Is_Library_Level_Entity (Id) then
3594 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3596 -- If not library level entity, then indicate we don't know max
3597 -- tasks and also check task hierarchy restriction and blocking
3598 -- operation (since starting a task is definitely blocking!)
3601 Check_Restriction (Max_Tasks, N);
3602 Check_Restriction (No_Task_Hierarchy, N);
3603 Check_Potentially_Blocking_Operation (N);
3606 -- A rather specialized test. If we see two tasks being declared
3607 -- of the same type in the same object declaration, and the task
3608 -- has an entry with an address clause, we know that program error
3609 -- will be raised at run time since we can't have two tasks with
3610 -- entries at the same address.
3612 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3617 E := First_Entity (Etype (Id));
3618 while Present (E) loop
3619 if Ekind (E) = E_Entry
3620 and then Present (Get_Attribute_Definition_Clause
3621 (E, Attribute_Address))
3624 ("?more than one task with same entry address", N);
3626 ("\?Program_Error will be raised at run time", N);
3628 Make_Raise_Program_Error (Loc,
3629 Reason => PE_Duplicated_Entry_Address));
3639 -- Some simple constant-propagation: if the expression is a constant
3640 -- string initialized with a literal, share the literal. This avoids
3644 and then Is_Entity_Name (E)
3645 and then Ekind (Entity (E)) = E_Constant
3646 and then Base_Type (Etype (E)) = Standard_String
3649 Val : constant Node_Id := Constant_Value (Entity (E));
3652 and then Nkind (Val) = N_String_Literal
3654 Rewrite (E, New_Copy (Val));
3659 -- Another optimization: if the nominal subtype is unconstrained and
3660 -- the expression is a function call that returns an unconstrained
3661 -- type, rewrite the declaration as a renaming of the result of the
3662 -- call. The exceptions below are cases where the copy is expected,
3663 -- either by the back end (Aliased case) or by the semantics, as for
3664 -- initializing controlled types or copying tags for classwide types.
3667 and then Nkind (E) = N_Explicit_Dereference
3668 and then Nkind (Original_Node (E)) = N_Function_Call
3669 and then not Is_Library_Level_Entity (Id)
3670 and then not Is_Constrained (Underlying_Type (T))
3671 and then not Is_Aliased (Id)
3672 and then not Is_Class_Wide_Type (T)
3673 and then not Is_Controlled (T)
3674 and then not Has_Controlled_Component (Base_Type (T))
3675 and then Expander_Active
3678 Make_Object_Renaming_Declaration (Loc,
3679 Defining_Identifier => Id,
3680 Access_Definition => Empty,
3681 Subtype_Mark => New_Occurrence_Of
3682 (Base_Type (Etype (Id)), Loc),
3685 Set_Renamed_Object (Id, E);
3687 -- Force generation of debugging information for the constant and for
3688 -- the renamed function call.
3690 Set_Debug_Info_Needed (Id);
3691 Set_Debug_Info_Needed (Entity (Prefix (E)));
3694 if Present (Prev_Entity)
3695 and then Is_Frozen (Prev_Entity)
3696 and then not Error_Posted (Id)
3698 Error_Msg_N ("full constant declaration appears too late", N);
3701 Check_Eliminated (Id);
3703 -- Deal with setting In_Private_Part flag if in private part
3705 if Ekind (Scope (Id)) = E_Package
3706 and then In_Private_Part (Scope (Id))
3708 Set_In_Private_Part (Id);
3711 -- Check for violation of No_Local_Timing_Events
3713 if Restriction_Check_Required (No_Local_Timing_Events)
3714 and then not Is_Library_Level_Entity (Id)
3715 and then Is_RTE (Etype (Id), RE_Timing_Event)
3717 Check_Restriction (No_Local_Timing_Events, N);
3721 if Has_Aspects (N) then
3722 Analyze_Aspect_Specifications (N, Id);
3725 -- Generate 'I' xref for object initialization at definition, only used
3726 -- for the local xref section used in ALFA mode.
3728 if ALFA_Mode and then Present (Expression (Original_Node (N))) then
3729 Generate_Reference (Id, Id, 'I');
3731 end Analyze_Object_Declaration;
3733 ---------------------------
3734 -- Analyze_Others_Choice --
3735 ---------------------------
3737 -- Nothing to do for the others choice node itself, the semantic analysis
3738 -- of the others choice will occur as part of the processing of the parent
3740 procedure Analyze_Others_Choice (N : Node_Id) is
3741 pragma Warnings (Off, N);
3744 end Analyze_Others_Choice;
3746 -------------------------------------------
3747 -- Analyze_Private_Extension_Declaration --
3748 -------------------------------------------
3750 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3751 T : constant Entity_Id := Defining_Identifier (N);
3752 Indic : constant Node_Id := Subtype_Indication (N);
3753 Parent_Type : Entity_Id;
3754 Parent_Base : Entity_Id;
3757 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3759 if Is_Non_Empty_List (Interface_List (N)) then
3765 Intf := First (Interface_List (N));
3766 while Present (Intf) loop
3767 T := Find_Type_Of_Subtype_Indic (Intf);
3769 Diagnose_Interface (Intf, T);
3775 Generate_Definition (T);
3777 -- For other than Ada 2012, just enter the name in the current scope
3779 if Ada_Version < Ada_2012 then
3782 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3783 -- case of private type that completes an incomplete type.
3790 Prev := Find_Type_Name (N);
3792 pragma Assert (Prev = T
3793 or else (Ekind (Prev) = E_Incomplete_Type
3794 and then Present (Full_View (Prev))
3795 and then Full_View (Prev) = T));
3799 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3800 Parent_Base := Base_Type (Parent_Type);
3802 if Parent_Type = Any_Type
3803 or else Etype (Parent_Type) = Any_Type
3805 Set_Ekind (T, Ekind (Parent_Type));
3806 Set_Etype (T, Any_Type);
3809 elsif not Is_Tagged_Type (Parent_Type) then
3811 ("parent of type extension must be a tagged type ", Indic);
3814 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3815 Error_Msg_N ("premature derivation of incomplete type", Indic);
3818 elsif Is_Concurrent_Type (Parent_Type) then
3820 ("parent type of a private extension cannot be "
3821 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3823 Set_Etype (T, Any_Type);
3824 Set_Ekind (T, E_Limited_Private_Type);
3825 Set_Private_Dependents (T, New_Elmt_List);
3826 Set_Error_Posted (T);
3830 -- Perhaps the parent type should be changed to the class-wide type's
3831 -- specific type in this case to prevent cascading errors ???
3833 if Is_Class_Wide_Type (Parent_Type) then
3835 ("parent of type extension must not be a class-wide type", Indic);
3839 if (not Is_Package_Or_Generic_Package (Current_Scope)
3840 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3841 or else In_Private_Part (Current_Scope)
3844 Error_Msg_N ("invalid context for private extension", N);
3847 -- Set common attributes
3849 Set_Is_Pure (T, Is_Pure (Current_Scope));
3850 Set_Scope (T, Current_Scope);
3851 Set_Ekind (T, E_Record_Type_With_Private);
3852 Init_Size_Align (T);
3854 Set_Etype (T, Parent_Base);
3855 Set_Has_Task (T, Has_Task (Parent_Base));
3857 Set_Convention (T, Convention (Parent_Type));
3858 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3859 Set_Is_First_Subtype (T);
3860 Make_Class_Wide_Type (T);
3862 if Unknown_Discriminants_Present (N) then
3863 Set_Discriminant_Constraint (T, No_Elist);
3866 Build_Derived_Record_Type (N, Parent_Type, T);
3868 -- Propagate inherited invariant information. The new type has
3869 -- invariants, if the parent type has inheritable invariants,
3870 -- and these invariants can in turn be inherited.
3872 if Has_Inheritable_Invariants (Parent_Type) then
3873 Set_Has_Inheritable_Invariants (T);
3874 Set_Has_Invariants (T);
3877 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3878 -- synchronized formal derived type.
3880 if Ada_Version >= Ada_2005
3881 and then Synchronized_Present (N)
3883 Set_Is_Limited_Record (T);
3885 -- Formal derived type case
3887 if Is_Generic_Type (T) then
3889 -- The parent must be a tagged limited type or a synchronized
3892 if (not Is_Tagged_Type (Parent_Type)
3893 or else not Is_Limited_Type (Parent_Type))
3895 (not Is_Interface (Parent_Type)
3896 or else not Is_Synchronized_Interface (Parent_Type))
3898 Error_Msg_NE ("parent type of & must be tagged limited " &
3899 "or synchronized", N, T);
3902 -- The progenitors (if any) must be limited or synchronized
3905 if Present (Interfaces (T)) then
3908 Iface_Elmt : Elmt_Id;
3911 Iface_Elmt := First_Elmt (Interfaces (T));
3912 while Present (Iface_Elmt) loop
3913 Iface := Node (Iface_Elmt);
3915 if not Is_Limited_Interface (Iface)
3916 and then not Is_Synchronized_Interface (Iface)
3918 Error_Msg_NE ("progenitor & must be limited " &
3919 "or synchronized", N, Iface);
3922 Next_Elmt (Iface_Elmt);
3927 -- Regular derived extension, the parent must be a limited or
3928 -- synchronized interface.
3931 if not Is_Interface (Parent_Type)
3932 or else (not Is_Limited_Interface (Parent_Type)
3934 not Is_Synchronized_Interface (Parent_Type))
3937 ("parent type of & must be limited interface", N, T);
3941 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3942 -- extension with a synchronized parent must be explicitly declared
3943 -- synchronized, because the full view will be a synchronized type.
3944 -- This must be checked before the check for limited types below,
3945 -- to ensure that types declared limited are not allowed to extend
3946 -- synchronized interfaces.
3948 elsif Is_Interface (Parent_Type)
3949 and then Is_Synchronized_Interface (Parent_Type)
3950 and then not Synchronized_Present (N)
3953 ("private extension of& must be explicitly synchronized",
3956 elsif Limited_Present (N) then
3957 Set_Is_Limited_Record (T);
3959 if not Is_Limited_Type (Parent_Type)
3961 (not Is_Interface (Parent_Type)
3962 or else not Is_Limited_Interface (Parent_Type))
3964 Error_Msg_NE ("parent type& of limited extension must be limited",
3970 if Has_Aspects (N) then
3971 Analyze_Aspect_Specifications (N, T);
3973 end Analyze_Private_Extension_Declaration;
3975 ---------------------------------
3976 -- Analyze_Subtype_Declaration --
3977 ---------------------------------
3979 procedure Analyze_Subtype_Declaration
3981 Skip : Boolean := False)
3983 Id : constant Entity_Id := Defining_Identifier (N);
3985 R_Checks : Check_Result;
3988 Generate_Definition (Id);
3989 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3990 Init_Size_Align (Id);
3992 -- The following guard condition on Enter_Name is to handle cases where
3993 -- the defining identifier has already been entered into the scope but
3994 -- the declaration as a whole needs to be analyzed.
3996 -- This case in particular happens for derived enumeration types. The
3997 -- derived enumeration type is processed as an inserted enumeration type
3998 -- declaration followed by a rewritten subtype declaration. The defining
3999 -- identifier, however, is entered into the name scope very early in the
4000 -- processing of the original type declaration and therefore needs to be
4001 -- avoided here, when the created subtype declaration is analyzed. (See
4002 -- Build_Derived_Types)
4004 -- This also happens when the full view of a private type is derived
4005 -- type with constraints. In this case the entity has been introduced
4006 -- in the private declaration.
4009 or else (Present (Etype (Id))
4010 and then (Is_Private_Type (Etype (Id))
4011 or else Is_Task_Type (Etype (Id))
4012 or else Is_Rewrite_Substitution (N)))
4020 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4022 -- Inherit common attributes
4024 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4025 Set_Is_Volatile (Id, Is_Volatile (T));
4026 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4027 Set_Is_Atomic (Id, Is_Atomic (T));
4028 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4029 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4030 Set_Convention (Id, Convention (T));
4032 -- If ancestor has predicates then so does the subtype, and in addition
4033 -- we must delay the freeze to properly arrange predicate inheritance.
4035 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4036 -- which T = ID, so the above tests and assignments do nothing???
4038 if Has_Predicates (T)
4039 or else (Present (Ancestor_Subtype (T))
4040 and then Has_Predicates (Ancestor_Subtype (T)))
4042 Set_Has_Predicates (Id);
4043 Set_Has_Delayed_Freeze (Id);
4046 -- Subtype of Boolean cannot have a constraint in SPARK
4048 if Is_Boolean_Type (T)
4049 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4051 Check_SPARK_Restriction
4052 ("subtype of Boolean cannot have constraint", N);
4055 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4057 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4063 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4064 One_Cstr := First (Constraints (Cstr));
4065 while Present (One_Cstr) loop
4067 -- Index or discriminant constraint in SPARK must be a
4071 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4073 Check_SPARK_Restriction
4074 ("subtype mark required", One_Cstr);
4076 -- String subtype must have a lower bound of 1 in SPARK.
4077 -- Note that we do not need to test for the non-static case
4078 -- here, since that was already taken care of in
4079 -- Process_Range_Expr_In_Decl.
4081 elsif Base_Type (T) = Standard_String then
4082 Get_Index_Bounds (One_Cstr, Low, High);
4084 if Is_OK_Static_Expression (Low)
4085 and then Expr_Value (Low) /= 1
4087 Check_SPARK_Restriction
4088 ("String subtype must have lower bound of 1", N);
4098 -- In the case where there is no constraint given in the subtype
4099 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4100 -- semantic attributes must be established here.
4102 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4103 Set_Etype (Id, Base_Type (T));
4105 -- Subtype of unconstrained array without constraint is not allowed
4108 if Is_Array_Type (T)
4109 and then not Is_Constrained (T)
4111 Check_SPARK_Restriction
4112 ("subtype of unconstrained array must have constraint", N);
4117 Set_Ekind (Id, E_Array_Subtype);
4118 Copy_Array_Subtype_Attributes (Id, T);
4120 when Decimal_Fixed_Point_Kind =>
4121 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4122 Set_Digits_Value (Id, Digits_Value (T));
4123 Set_Delta_Value (Id, Delta_Value (T));
4124 Set_Scale_Value (Id, Scale_Value (T));
4125 Set_Small_Value (Id, Small_Value (T));
4126 Set_Scalar_Range (Id, Scalar_Range (T));
4127 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4128 Set_Is_Constrained (Id, Is_Constrained (T));
4129 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4130 Set_RM_Size (Id, RM_Size (T));
4132 when Enumeration_Kind =>
4133 Set_Ekind (Id, E_Enumeration_Subtype);
4134 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4135 Set_Scalar_Range (Id, Scalar_Range (T));
4136 Set_Is_Character_Type (Id, Is_Character_Type (T));
4137 Set_Is_Constrained (Id, Is_Constrained (T));
4138 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4139 Set_RM_Size (Id, RM_Size (T));
4141 when Ordinary_Fixed_Point_Kind =>
4142 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4143 Set_Scalar_Range (Id, Scalar_Range (T));
4144 Set_Small_Value (Id, Small_Value (T));
4145 Set_Delta_Value (Id, Delta_Value (T));
4146 Set_Is_Constrained (Id, Is_Constrained (T));
4147 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4148 Set_RM_Size (Id, RM_Size (T));
4151 Set_Ekind (Id, E_Floating_Point_Subtype);
4152 Set_Scalar_Range (Id, Scalar_Range (T));
4153 Set_Digits_Value (Id, Digits_Value (T));
4154 Set_Is_Constrained (Id, Is_Constrained (T));
4156 when Signed_Integer_Kind =>
4157 Set_Ekind (Id, E_Signed_Integer_Subtype);
4158 Set_Scalar_Range (Id, Scalar_Range (T));
4159 Set_Is_Constrained (Id, Is_Constrained (T));
4160 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4161 Set_RM_Size (Id, RM_Size (T));
4163 when Modular_Integer_Kind =>
4164 Set_Ekind (Id, E_Modular_Integer_Subtype);
4165 Set_Scalar_Range (Id, Scalar_Range (T));
4166 Set_Is_Constrained (Id, Is_Constrained (T));
4167 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4168 Set_RM_Size (Id, RM_Size (T));
4170 when Class_Wide_Kind =>
4171 Set_Ekind (Id, E_Class_Wide_Subtype);
4172 Set_First_Entity (Id, First_Entity (T));
4173 Set_Last_Entity (Id, Last_Entity (T));
4174 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4175 Set_Cloned_Subtype (Id, T);
4176 Set_Is_Tagged_Type (Id, True);
4177 Set_Has_Unknown_Discriminants
4180 if Ekind (T) = E_Class_Wide_Subtype then
4181 Set_Equivalent_Type (Id, Equivalent_Type (T));
4184 when E_Record_Type | E_Record_Subtype =>
4185 Set_Ekind (Id, E_Record_Subtype);
4187 if Ekind (T) = E_Record_Subtype
4188 and then Present (Cloned_Subtype (T))
4190 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4192 Set_Cloned_Subtype (Id, T);
4195 Set_First_Entity (Id, First_Entity (T));
4196 Set_Last_Entity (Id, Last_Entity (T));
4197 Set_Has_Discriminants (Id, Has_Discriminants (T));
4198 Set_Is_Constrained (Id, Is_Constrained (T));
4199 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4200 Set_Has_Unknown_Discriminants
4201 (Id, Has_Unknown_Discriminants (T));
4203 if Has_Discriminants (T) then
4204 Set_Discriminant_Constraint
4205 (Id, Discriminant_Constraint (T));
4206 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4208 elsif Has_Unknown_Discriminants (Id) then
4209 Set_Discriminant_Constraint (Id, No_Elist);
4212 if Is_Tagged_Type (T) then
4213 Set_Is_Tagged_Type (Id);
4214 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4215 Set_Direct_Primitive_Operations
4216 (Id, Direct_Primitive_Operations (T));
4217 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4219 if Is_Interface (T) then
4220 Set_Is_Interface (Id);
4221 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4225 when Private_Kind =>
4226 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4227 Set_Has_Discriminants (Id, Has_Discriminants (T));
4228 Set_Is_Constrained (Id, Is_Constrained (T));
4229 Set_First_Entity (Id, First_Entity (T));
4230 Set_Last_Entity (Id, Last_Entity (T));
4231 Set_Private_Dependents (Id, New_Elmt_List);
4232 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4233 Set_Has_Unknown_Discriminants
4234 (Id, Has_Unknown_Discriminants (T));
4235 Set_Known_To_Have_Preelab_Init
4236 (Id, Known_To_Have_Preelab_Init (T));
4238 if Is_Tagged_Type (T) then
4239 Set_Is_Tagged_Type (Id);
4240 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4241 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4242 Set_Direct_Primitive_Operations (Id,
4243 Direct_Primitive_Operations (T));
4246 -- In general the attributes of the subtype of a private type
4247 -- are the attributes of the partial view of parent. However,
4248 -- the full view may be a discriminated type, and the subtype
4249 -- must share the discriminant constraint to generate correct
4250 -- calls to initialization procedures.
4252 if Has_Discriminants (T) then
4253 Set_Discriminant_Constraint
4254 (Id, Discriminant_Constraint (T));
4255 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4257 elsif Present (Full_View (T))
4258 and then Has_Discriminants (Full_View (T))
4260 Set_Discriminant_Constraint
4261 (Id, Discriminant_Constraint (Full_View (T)));
4262 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4264 -- This would seem semantically correct, but apparently
4265 -- confuses the back-end. To be explained and checked with
4266 -- current version ???
4268 -- Set_Has_Discriminants (Id);
4271 Prepare_Private_Subtype_Completion (Id, N);
4274 Set_Ekind (Id, E_Access_Subtype);
4275 Set_Is_Constrained (Id, Is_Constrained (T));
4276 Set_Is_Access_Constant
4277 (Id, Is_Access_Constant (T));
4278 Set_Directly_Designated_Type
4279 (Id, Designated_Type (T));
4280 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4282 -- A Pure library_item must not contain the declaration of a
4283 -- named access type, except within a subprogram, generic
4284 -- subprogram, task unit, or protected unit, or if it has
4285 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4287 if Comes_From_Source (Id)
4288 and then In_Pure_Unit
4289 and then not In_Subprogram_Task_Protected_Unit
4290 and then not No_Pool_Assigned (Id)
4293 ("named access types not allowed in pure unit", N);
4296 when Concurrent_Kind =>
4297 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4298 Set_Corresponding_Record_Type (Id,
4299 Corresponding_Record_Type (T));
4300 Set_First_Entity (Id, First_Entity (T));
4301 Set_First_Private_Entity (Id, First_Private_Entity (T));
4302 Set_Has_Discriminants (Id, Has_Discriminants (T));
4303 Set_Is_Constrained (Id, Is_Constrained (T));
4304 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4305 Set_Last_Entity (Id, Last_Entity (T));
4307 if Has_Discriminants (T) then
4308 Set_Discriminant_Constraint (Id,
4309 Discriminant_Constraint (T));
4310 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4313 when E_Incomplete_Type =>
4314 if Ada_Version >= Ada_2005 then
4315 Set_Ekind (Id, E_Incomplete_Subtype);
4317 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4318 -- of an incomplete type visible through a limited
4321 if From_With_Type (T)
4322 and then Present (Non_Limited_View (T))
4324 Set_From_With_Type (Id);
4325 Set_Non_Limited_View (Id, Non_Limited_View (T));
4327 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4328 -- to the private dependents of the original incomplete
4329 -- type for future transformation.
4332 Append_Elmt (Id, Private_Dependents (T));
4335 -- If the subtype name denotes an incomplete type an error
4336 -- was already reported by Process_Subtype.
4339 Set_Etype (Id, Any_Type);
4343 raise Program_Error;
4347 if Etype (Id) = Any_Type then
4351 -- Some common processing on all types
4353 Set_Size_Info (Id, T);
4354 Set_First_Rep_Item (Id, First_Rep_Item (T));
4358 Set_Is_Immediately_Visible (Id, True);
4359 Set_Depends_On_Private (Id, Has_Private_Component (T));
4360 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4362 if Is_Interface (T) then
4363 Set_Is_Interface (Id);
4366 if Present (Generic_Parent_Type (N))
4369 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4371 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4372 /= N_Formal_Private_Type_Definition)
4374 if Is_Tagged_Type (Id) then
4376 -- If this is a generic actual subtype for a synchronized type,
4377 -- the primitive operations are those of the corresponding record
4378 -- for which there is a separate subtype declaration.
4380 if Is_Concurrent_Type (Id) then
4382 elsif Is_Class_Wide_Type (Id) then
4383 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4385 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4388 elsif Scope (Etype (Id)) /= Standard_Standard then
4389 Derive_Subprograms (Generic_Parent_Type (N), Id);
4393 if Is_Private_Type (T)
4394 and then Present (Full_View (T))
4396 Conditional_Delay (Id, Full_View (T));
4398 -- The subtypes of components or subcomponents of protected types
4399 -- do not need freeze nodes, which would otherwise appear in the
4400 -- wrong scope (before the freeze node for the protected type). The
4401 -- proper subtypes are those of the subcomponents of the corresponding
4404 elsif Ekind (Scope (Id)) /= E_Protected_Type
4405 and then Present (Scope (Scope (Id))) -- error defense!
4406 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4408 Conditional_Delay (Id, T);
4411 -- Check that Constraint_Error is raised for a scalar subtype indication
4412 -- when the lower or upper bound of a non-null range lies outside the
4413 -- range of the type mark.
4415 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4416 if Is_Scalar_Type (Etype (Id))
4417 and then Scalar_Range (Id) /=
4418 Scalar_Range (Etype (Subtype_Mark
4419 (Subtype_Indication (N))))
4423 Etype (Subtype_Mark (Subtype_Indication (N))));
4425 -- In the array case, check compatibility for each index
4427 elsif Is_Array_Type (Etype (Id))
4428 and then Present (First_Index (Id))
4430 -- This really should be a subprogram that finds the indications
4434 Subt_Index : Node_Id := First_Index (Id);
4435 Target_Index : Node_Id :=
4437 (Subtype_Mark (Subtype_Indication (N))));
4438 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4441 while Present (Subt_Index) loop
4442 if ((Nkind (Subt_Index) = N_Identifier
4443 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4444 or else Nkind (Subt_Index) = N_Subtype_Indication)
4446 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4449 Target_Typ : constant Entity_Id :=
4450 Etype (Target_Index);
4454 (Scalar_Range (Etype (Subt_Index)),
4457 Defining_Identifier (N));
4459 -- Reset Has_Dynamic_Range_Check on the subtype to
4460 -- prevent elision of the index check due to a dynamic
4461 -- check generated for a preceding index (needed since
4462 -- Insert_Range_Checks tries to avoid generating
4463 -- redundant checks on a given declaration).
4465 Set_Has_Dynamic_Range_Check (N, False);
4471 Sloc (Defining_Identifier (N)));
4473 -- Record whether this index involved a dynamic check
4476 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4480 Next_Index (Subt_Index);
4481 Next_Index (Target_Index);
4484 -- Finally, mark whether the subtype involves dynamic checks
4486 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4491 -- Make sure that generic actual types are properly frozen. The subtype
4492 -- is marked as a generic actual type when the enclosing instance is
4493 -- analyzed, so here we identify the subtype from the tree structure.
4496 and then Is_Generic_Actual_Type (Id)
4497 and then In_Instance
4498 and then not Comes_From_Source (N)
4499 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4500 and then Is_Frozen (T)
4502 Freeze_Before (N, Id);
4505 Set_Optimize_Alignment_Flags (Id);
4506 Check_Eliminated (Id);
4509 if Has_Aspects (N) then
4510 Analyze_Aspect_Specifications (N, Id);
4512 end Analyze_Subtype_Declaration;
4514 --------------------------------
4515 -- Analyze_Subtype_Indication --
4516 --------------------------------
4518 procedure Analyze_Subtype_Indication (N : Node_Id) is
4519 T : constant Entity_Id := Subtype_Mark (N);
4520 R : constant Node_Id := Range_Expression (Constraint (N));
4527 Set_Etype (N, Etype (R));
4528 Resolve (R, Entity (T));
4530 Set_Error_Posted (R);
4531 Set_Error_Posted (T);
4533 end Analyze_Subtype_Indication;
4535 --------------------------
4536 -- Analyze_Variant_Part --
4537 --------------------------
4539 procedure Analyze_Variant_Part (N : Node_Id) is
4541 procedure Non_Static_Choice_Error (Choice : Node_Id);
4542 -- Error routine invoked by the generic instantiation below when the
4543 -- variant part has a non static choice.
4545 procedure Process_Declarations (Variant : Node_Id);
4546 -- Analyzes all the declarations associated with a Variant. Needed by
4547 -- the generic instantiation below.
4549 package Variant_Choices_Processing is new
4550 Generic_Choices_Processing
4551 (Get_Alternatives => Variants,
4552 Get_Choices => Discrete_Choices,
4553 Process_Empty_Choice => No_OP,
4554 Process_Non_Static_Choice => Non_Static_Choice_Error,
4555 Process_Associated_Node => Process_Declarations);
4556 use Variant_Choices_Processing;
4557 -- Instantiation of the generic choice processing package
4559 -----------------------------
4560 -- Non_Static_Choice_Error --
4561 -----------------------------
4563 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4565 Flag_Non_Static_Expr
4566 ("choice given in variant part is not static!", Choice);
4567 end Non_Static_Choice_Error;
4569 --------------------------
4570 -- Process_Declarations --
4571 --------------------------
4573 procedure Process_Declarations (Variant : Node_Id) is
4575 if not Null_Present (Component_List (Variant)) then
4576 Analyze_Declarations (Component_Items (Component_List (Variant)));
4578 if Present (Variant_Part (Component_List (Variant))) then
4579 Analyze (Variant_Part (Component_List (Variant)));
4582 end Process_Declarations;
4586 Discr_Name : Node_Id;
4587 Discr_Type : Entity_Id;
4589 Dont_Care : Boolean;
4590 Others_Present : Boolean := False;
4592 pragma Warnings (Off, Dont_Care);
4593 pragma Warnings (Off, Others_Present);
4594 -- We don't care about the assigned values of any of these
4596 -- Start of processing for Analyze_Variant_Part
4599 Discr_Name := Name (N);
4600 Analyze (Discr_Name);
4602 -- If Discr_Name bad, get out (prevent cascaded errors)
4604 if Etype (Discr_Name) = Any_Type then
4608 -- Check invalid discriminant in variant part
4610 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4611 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4614 Discr_Type := Etype (Entity (Discr_Name));
4616 if not Is_Discrete_Type (Discr_Type) then
4618 ("discriminant in a variant part must be of a discrete type",
4623 -- Call the instantiated Analyze_Choices which does the rest of the work
4625 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4626 end Analyze_Variant_Part;
4628 ----------------------------
4629 -- Array_Type_Declaration --
4630 ----------------------------
4632 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4633 Component_Def : constant Node_Id := Component_Definition (Def);
4634 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4635 Element_Type : Entity_Id;
4636 Implicit_Base : Entity_Id;
4638 Related_Id : Entity_Id := Empty;
4640 P : constant Node_Id := Parent (Def);
4642 T_In_ALFA : Boolean := True;
4645 if Nkind (Def) = N_Constrained_Array_Definition then
4646 Index := First (Discrete_Subtype_Definitions (Def));
4648 Index := First (Subtype_Marks (Def));
4651 -- Find proper names for the implicit types which may be public. In case
4652 -- of anonymous arrays we use the name of the first object of that type
4656 Related_Id := Defining_Identifier (P);
4662 while Present (Index) loop
4665 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4666 Check_SPARK_Restriction ("subtype mark required", Index);
4669 if Present (Etype (Index))
4670 and then not Is_In_ALFA (Etype (Index))
4675 -- Add a subtype declaration for each index of private array type
4676 -- declaration whose etype is also private. For example:
4679 -- type Index is private;
4681 -- type Table is array (Index) of ...
4684 -- This is currently required by the expander for the internally
4685 -- generated equality subprogram of records with variant parts in
4686 -- which the etype of some component is such private type.
4688 if Ekind (Current_Scope) = E_Package
4689 and then In_Private_Part (Current_Scope)
4690 and then Has_Private_Declaration (Etype (Index))
4693 Loc : constant Source_Ptr := Sloc (Def);
4698 New_E := Make_Temporary (Loc, 'T');
4699 Set_Is_Internal (New_E);
4702 Make_Subtype_Declaration (Loc,
4703 Defining_Identifier => New_E,
4704 Subtype_Indication =>
4705 New_Occurrence_Of (Etype (Index), Loc));
4707 Insert_Before (Parent (Def), Decl);
4709 Set_Etype (Index, New_E);
4711 -- If the index is a range the Entity attribute is not
4712 -- available. Example:
4715 -- type T is private;
4717 -- type T is new Natural;
4718 -- Table : array (T(1) .. T(10)) of Boolean;
4721 if Nkind (Index) /= N_Range then
4722 Set_Entity (Index, New_E);
4727 Make_Index (Index, P, Related_Id, Nb_Index);
4729 -- Check error of subtype with predicate for index type
4731 Bad_Predicated_Subtype_Use
4732 ("subtype& has predicate, not allowed as index subtype",
4733 Index, Etype (Index));
4735 -- Move to next index
4738 Nb_Index := Nb_Index + 1;
4741 -- Process subtype indication if one is present
4743 if Present (Component_Typ) then
4744 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4746 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4747 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4750 if Present (Element_Type)
4751 and then not Is_In_ALFA (Element_Type)
4756 -- Ada 2005 (AI-230): Access Definition case
4758 else pragma Assert (Present (Access_Definition (Component_Def)));
4762 -- Indicate that the anonymous access type is created by the
4763 -- array type declaration.
4765 Element_Type := Access_Definition
4767 N => Access_Definition (Component_Def));
4768 Set_Is_Local_Anonymous_Access (Element_Type);
4770 -- Propagate the parent. This field is needed if we have to generate
4771 -- the master_id associated with an anonymous access to task type
4772 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4774 Set_Parent (Element_Type, Parent (T));
4776 -- Ada 2005 (AI-230): In case of components that are anonymous access
4777 -- types the level of accessibility depends on the enclosing type
4780 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4782 -- Ada 2005 (AI-254)
4785 CD : constant Node_Id :=
4786 Access_To_Subprogram_Definition
4787 (Access_Definition (Component_Def));
4789 if Present (CD) and then Protected_Present (CD) then
4791 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4796 -- Constrained array case
4799 T := Create_Itype (E_Void, P, Related_Id, 'T');
4802 if Nkind (Def) = N_Constrained_Array_Definition then
4804 -- Establish Implicit_Base as unconstrained base type
4806 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4808 Set_Etype (Implicit_Base, Implicit_Base);
4809 Set_Scope (Implicit_Base, Current_Scope);
4810 Set_Has_Delayed_Freeze (Implicit_Base);
4812 -- The constrained array type is a subtype of the unconstrained one
4814 Set_Ekind (T, E_Array_Subtype);
4815 Init_Size_Align (T);
4816 Set_Etype (T, Implicit_Base);
4817 Set_Scope (T, Current_Scope);
4818 Set_Is_Constrained (T, True);
4819 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4820 Set_Has_Delayed_Freeze (T);
4822 -- Complete setup of implicit base type
4824 Set_First_Index (Implicit_Base, First_Index (T));
4825 Set_Component_Type (Implicit_Base, Element_Type);
4826 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4827 Set_Component_Size (Implicit_Base, Uint_0);
4828 Set_Packed_Array_Type (Implicit_Base, Empty);
4829 Set_Has_Controlled_Component
4830 (Implicit_Base, Has_Controlled_Component
4832 or else Is_Controlled
4834 Set_Finalize_Storage_Only
4835 (Implicit_Base, Finalize_Storage_Only
4838 -- Final check for static bounds on array
4840 if not Has_Static_Array_Bounds (T) then
4844 -- Unconstrained array case
4847 Set_Ekind (T, E_Array_Type);
4848 Init_Size_Align (T);
4850 Set_Scope (T, Current_Scope);
4851 Set_Component_Size (T, Uint_0);
4852 Set_Is_Constrained (T, False);
4853 Set_First_Index (T, First (Subtype_Marks (Def)));
4854 Set_Has_Delayed_Freeze (T, True);
4855 Set_Has_Task (T, Has_Task (Element_Type));
4856 Set_Has_Controlled_Component (T, Has_Controlled_Component
4859 Is_Controlled (Element_Type));
4860 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4864 -- Common attributes for both cases
4866 Set_Component_Type (Base_Type (T), Element_Type);
4867 Set_Packed_Array_Type (T, Empty);
4868 Set_Is_In_ALFA (T, T_In_ALFA);
4870 if Aliased_Present (Component_Definition (Def)) then
4871 Check_SPARK_Restriction
4872 ("aliased is not allowed", Component_Definition (Def));
4873 Set_Has_Aliased_Components (Etype (T));
4876 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4877 -- array type to ensure that objects of this type are initialized.
4879 if Ada_Version >= Ada_2005
4880 and then Can_Never_Be_Null (Element_Type)
4882 Set_Can_Never_Be_Null (T);
4884 if Null_Exclusion_Present (Component_Definition (Def))
4886 -- No need to check itypes because in their case this check was
4887 -- done at their point of creation
4889 and then not Is_Itype (Element_Type)
4892 ("`NOT NULL` not allowed (null already excluded)",
4893 Subtype_Indication (Component_Definition (Def)));
4897 Priv := Private_Component (Element_Type);
4899 if Present (Priv) then
4901 -- Check for circular definitions
4903 if Priv = Any_Type then
4904 Set_Component_Type (Etype (T), Any_Type);
4906 -- There is a gap in the visibility of operations on the composite
4907 -- type only if the component type is defined in a different scope.
4909 elsif Scope (Priv) = Current_Scope then
4912 elsif Is_Limited_Type (Priv) then
4913 Set_Is_Limited_Composite (Etype (T));
4914 Set_Is_Limited_Composite (T);
4916 Set_Is_Private_Composite (Etype (T));
4917 Set_Is_Private_Composite (T);
4921 -- A syntax error in the declaration itself may lead to an empty index
4922 -- list, in which case do a minimal patch.
4924 if No (First_Index (T)) then
4925 Error_Msg_N ("missing index definition in array type declaration", T);
4928 Indexes : constant List_Id :=
4929 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4931 Set_Discrete_Subtype_Definitions (Def, Indexes);
4932 Set_First_Index (T, First (Indexes));
4937 -- Create a concatenation operator for the new type. Internal array
4938 -- types created for packed entities do not need such, they are
4939 -- compatible with the user-defined type.
4941 if Number_Dimensions (T) = 1
4942 and then not Is_Packed_Array_Type (T)
4944 New_Concatenation_Op (T);
4947 -- In the case of an unconstrained array the parser has already verified
4948 -- that all the indexes are unconstrained but we still need to make sure
4949 -- that the element type is constrained.
4951 if Is_Indefinite_Subtype (Element_Type) then
4953 ("unconstrained element type in array declaration",
4954 Subtype_Indication (Component_Def));
4956 elsif Is_Abstract_Type (Element_Type) then
4958 ("the type of a component cannot be abstract",
4959 Subtype_Indication (Component_Def));
4961 end Array_Type_Declaration;
4963 ------------------------------------------------------
4964 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4965 ------------------------------------------------------
4967 function Replace_Anonymous_Access_To_Protected_Subprogram
4968 (N : Node_Id) return Entity_Id
4970 Loc : constant Source_Ptr := Sloc (N);
4972 Curr_Scope : constant Scope_Stack_Entry :=
4973 Scope_Stack.Table (Scope_Stack.Last);
4975 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
4982 Set_Is_Internal (Anon);
4985 when N_Component_Declaration |
4986 N_Unconstrained_Array_Definition |
4987 N_Constrained_Array_Definition =>
4988 Comp := Component_Definition (N);
4989 Acc := Access_Definition (Comp);
4991 when N_Discriminant_Specification =>
4992 Comp := Discriminant_Type (N);
4995 when N_Parameter_Specification =>
4996 Comp := Parameter_Type (N);
4999 when N_Access_Function_Definition =>
5000 Comp := Result_Definition (N);
5003 when N_Object_Declaration =>
5004 Comp := Object_Definition (N);
5007 when N_Function_Specification =>
5008 Comp := Result_Definition (N);
5012 raise Program_Error;
5015 Decl := Make_Full_Type_Declaration (Loc,
5016 Defining_Identifier => Anon,
5018 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
5020 Mark_Rewrite_Insertion (Decl);
5022 -- Insert the new declaration in the nearest enclosing scope. If the
5023 -- node is a body and N is its return type, the declaration belongs in
5024 -- the enclosing scope.
5028 if Nkind (P) = N_Subprogram_Body
5029 and then Nkind (N) = N_Function_Specification
5034 while Present (P) and then not Has_Declarations (P) loop
5038 pragma Assert (Present (P));
5040 if Nkind (P) = N_Package_Specification then
5041 Prepend (Decl, Visible_Declarations (P));
5043 Prepend (Decl, Declarations (P));
5046 -- Replace the anonymous type with an occurrence of the new declaration.
5047 -- In all cases the rewritten node does not have the null-exclusion
5048 -- attribute because (if present) it was already inherited by the
5049 -- anonymous entity (Anon). Thus, in case of components we do not
5050 -- inherit this attribute.
5052 if Nkind (N) = N_Parameter_Specification then
5053 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5054 Set_Etype (Defining_Identifier (N), Anon);
5055 Set_Null_Exclusion_Present (N, False);
5057 elsif Nkind (N) = N_Object_Declaration then
5058 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5059 Set_Etype (Defining_Identifier (N), Anon);
5061 elsif Nkind (N) = N_Access_Function_Definition then
5062 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5064 elsif Nkind (N) = N_Function_Specification then
5065 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5066 Set_Etype (Defining_Unit_Name (N), Anon);
5070 Make_Component_Definition (Loc,
5071 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5074 Mark_Rewrite_Insertion (Comp);
5076 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5080 -- Temporarily remove the current scope (record or subprogram) from
5081 -- the stack to add the new declarations to the enclosing scope.
5083 Scope_Stack.Decrement_Last;
5085 Set_Is_Itype (Anon);
5086 Scope_Stack.Append (Curr_Scope);
5089 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5090 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5092 end Replace_Anonymous_Access_To_Protected_Subprogram;
5094 -------------------------------
5095 -- Build_Derived_Access_Type --
5096 -------------------------------
5098 procedure Build_Derived_Access_Type
5100 Parent_Type : Entity_Id;
5101 Derived_Type : Entity_Id)
5103 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5105 Desig_Type : Entity_Id;
5107 Discr_Con_Elist : Elist_Id;
5108 Discr_Con_El : Elmt_Id;
5112 -- Set the designated type so it is available in case this is an access
5113 -- to a self-referential type, e.g. a standard list type with a next
5114 -- pointer. Will be reset after subtype is built.
5116 Set_Directly_Designated_Type
5117 (Derived_Type, Designated_Type (Parent_Type));
5119 Subt := Process_Subtype (S, N);
5121 if Nkind (S) /= N_Subtype_Indication
5122 and then Subt /= Base_Type (Subt)
5124 Set_Ekind (Derived_Type, E_Access_Subtype);
5127 if Ekind (Derived_Type) = E_Access_Subtype then
5129 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5130 Ibase : constant Entity_Id :=
5131 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5132 Svg_Chars : constant Name_Id := Chars (Ibase);
5133 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5136 Copy_Node (Pbase, Ibase);
5138 Set_Chars (Ibase, Svg_Chars);
5139 Set_Next_Entity (Ibase, Svg_Next_E);
5140 Set_Sloc (Ibase, Sloc (Derived_Type));
5141 Set_Scope (Ibase, Scope (Derived_Type));
5142 Set_Freeze_Node (Ibase, Empty);
5143 Set_Is_Frozen (Ibase, False);
5144 Set_Comes_From_Source (Ibase, False);
5145 Set_Is_First_Subtype (Ibase, False);
5147 Set_Etype (Ibase, Pbase);
5148 Set_Etype (Derived_Type, Ibase);
5152 Set_Directly_Designated_Type
5153 (Derived_Type, Designated_Type (Subt));
5155 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5156 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5157 Set_Size_Info (Derived_Type, Parent_Type);
5158 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5159 Set_Depends_On_Private (Derived_Type,
5160 Has_Private_Component (Derived_Type));
5161 Conditional_Delay (Derived_Type, Subt);
5163 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5164 -- that it is not redundant.
5166 if Null_Exclusion_Present (Type_Definition (N)) then
5167 Set_Can_Never_Be_Null (Derived_Type);
5169 if Can_Never_Be_Null (Parent_Type)
5173 ("`NOT NULL` not allowed (& already excludes null)",
5177 elsif Can_Never_Be_Null (Parent_Type) then
5178 Set_Can_Never_Be_Null (Derived_Type);
5181 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5182 -- the root type for this information.
5184 -- Apply range checks to discriminants for derived record case
5185 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5187 Desig_Type := Designated_Type (Derived_Type);
5188 if Is_Composite_Type (Desig_Type)
5189 and then (not Is_Array_Type (Desig_Type))
5190 and then Has_Discriminants (Desig_Type)
5191 and then Base_Type (Desig_Type) /= Desig_Type
5193 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5194 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5196 Discr := First_Discriminant (Base_Type (Desig_Type));
5197 while Present (Discr_Con_El) loop
5198 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5199 Next_Elmt (Discr_Con_El);
5200 Next_Discriminant (Discr);
5203 end Build_Derived_Access_Type;
5205 ------------------------------
5206 -- Build_Derived_Array_Type --
5207 ------------------------------
5209 procedure Build_Derived_Array_Type
5211 Parent_Type : Entity_Id;
5212 Derived_Type : Entity_Id)
5214 Loc : constant Source_Ptr := Sloc (N);
5215 Tdef : constant Node_Id := Type_Definition (N);
5216 Indic : constant Node_Id := Subtype_Indication (Tdef);
5217 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5218 Implicit_Base : Entity_Id;
5219 New_Indic : Node_Id;
5221 procedure Make_Implicit_Base;
5222 -- If the parent subtype is constrained, the derived type is a subtype
5223 -- of an implicit base type derived from the parent base.
5225 ------------------------
5226 -- Make_Implicit_Base --
5227 ------------------------
5229 procedure Make_Implicit_Base is
5232 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5234 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5235 Set_Etype (Implicit_Base, Parent_Base);
5237 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5238 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5240 Set_Has_Delayed_Freeze (Implicit_Base, True);
5241 end Make_Implicit_Base;
5243 -- Start of processing for Build_Derived_Array_Type
5246 if not Is_Constrained (Parent_Type) then
5247 if Nkind (Indic) /= N_Subtype_Indication then
5248 Set_Ekind (Derived_Type, E_Array_Type);
5250 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5251 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5253 Set_Has_Delayed_Freeze (Derived_Type, True);
5257 Set_Etype (Derived_Type, Implicit_Base);
5260 Make_Subtype_Declaration (Loc,
5261 Defining_Identifier => Derived_Type,
5262 Subtype_Indication =>
5263 Make_Subtype_Indication (Loc,
5264 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5265 Constraint => Constraint (Indic)));
5267 Rewrite (N, New_Indic);
5272 if Nkind (Indic) /= N_Subtype_Indication then
5275 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5276 Set_Etype (Derived_Type, Implicit_Base);
5277 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5280 Error_Msg_N ("illegal constraint on constrained type", Indic);
5284 -- If parent type is not a derived type itself, and is declared in
5285 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5286 -- the new type's concatenation operator since Derive_Subprograms
5287 -- will not inherit the parent's operator. If the parent type is
5288 -- unconstrained, the operator is of the unconstrained base type.
5290 if Number_Dimensions (Parent_Type) = 1
5291 and then not Is_Limited_Type (Parent_Type)
5292 and then not Is_Derived_Type (Parent_Type)
5293 and then not Is_Package_Or_Generic_Package
5294 (Scope (Base_Type (Parent_Type)))
5296 if not Is_Constrained (Parent_Type)
5297 and then Is_Constrained (Derived_Type)
5299 New_Concatenation_Op (Implicit_Base);
5301 New_Concatenation_Op (Derived_Type);
5304 end Build_Derived_Array_Type;
5306 -----------------------------------
5307 -- Build_Derived_Concurrent_Type --
5308 -----------------------------------
5310 procedure Build_Derived_Concurrent_Type
5312 Parent_Type : Entity_Id;
5313 Derived_Type : Entity_Id)
5315 Loc : constant Source_Ptr := Sloc (N);
5317 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5318 Corr_Decl : Node_Id;
5319 Corr_Decl_Needed : Boolean;
5320 -- If the derived type has fewer discriminants than its parent, the
5321 -- corresponding record is also a derived type, in order to account for
5322 -- the bound discriminants. We create a full type declaration for it in
5325 Constraint_Present : constant Boolean :=
5326 Nkind (Subtype_Indication (Type_Definition (N))) =
5327 N_Subtype_Indication;
5329 D_Constraint : Node_Id;
5330 New_Constraint : Elist_Id;
5331 Old_Disc : Entity_Id;
5332 New_Disc : Entity_Id;
5336 Set_Stored_Constraint (Derived_Type, No_Elist);
5337 Corr_Decl_Needed := False;
5340 if Present (Discriminant_Specifications (N))
5341 and then Constraint_Present
5343 Old_Disc := First_Discriminant (Parent_Type);
5344 New_Disc := First (Discriminant_Specifications (N));
5345 while Present (New_Disc) and then Present (Old_Disc) loop
5346 Next_Discriminant (Old_Disc);
5351 if Present (Old_Disc) and then Expander_Active then
5353 -- The new type has fewer discriminants, so we need to create a new
5354 -- corresponding record, which is derived from the corresponding
5355 -- record of the parent, and has a stored constraint that captures
5356 -- the values of the discriminant constraints. The corresponding
5357 -- record is needed only if expander is active and code generation is
5360 -- The type declaration for the derived corresponding record has the
5361 -- same discriminant part and constraints as the current declaration.
5362 -- Copy the unanalyzed tree to build declaration.
5364 Corr_Decl_Needed := True;
5365 New_N := Copy_Separate_Tree (N);
5368 Make_Full_Type_Declaration (Loc,
5369 Defining_Identifier => Corr_Record,
5370 Discriminant_Specifications =>
5371 Discriminant_Specifications (New_N),
5373 Make_Derived_Type_Definition (Loc,
5374 Subtype_Indication =>
5375 Make_Subtype_Indication (Loc,
5378 (Corresponding_Record_Type (Parent_Type), Loc),
5381 (Subtype_Indication (Type_Definition (New_N))))));
5384 -- Copy Storage_Size and Relative_Deadline variables if task case
5386 if Is_Task_Type (Parent_Type) then
5387 Set_Storage_Size_Variable (Derived_Type,
5388 Storage_Size_Variable (Parent_Type));
5389 Set_Relative_Deadline_Variable (Derived_Type,
5390 Relative_Deadline_Variable (Parent_Type));
5393 if Present (Discriminant_Specifications (N)) then
5394 Push_Scope (Derived_Type);
5395 Check_Or_Process_Discriminants (N, Derived_Type);
5397 if Constraint_Present then
5399 Expand_To_Stored_Constraint
5401 Build_Discriminant_Constraints
5403 Subtype_Indication (Type_Definition (N)), True));
5408 elsif Constraint_Present then
5410 -- Build constrained subtype and derive from it
5413 Loc : constant Source_Ptr := Sloc (N);
5414 Anon : constant Entity_Id :=
5415 Make_Defining_Identifier (Loc,
5416 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5421 Make_Subtype_Declaration (Loc,
5422 Defining_Identifier => Anon,
5423 Subtype_Indication =>
5424 Subtype_Indication (Type_Definition (N)));
5425 Insert_Before (N, Decl);
5428 Rewrite (Subtype_Indication (Type_Definition (N)),
5429 New_Occurrence_Of (Anon, Loc));
5430 Set_Analyzed (Derived_Type, False);
5436 -- By default, operations and private data are inherited from parent.
5437 -- However, in the presence of bound discriminants, a new corresponding
5438 -- record will be created, see below.
5440 Set_Has_Discriminants
5441 (Derived_Type, Has_Discriminants (Parent_Type));
5442 Set_Corresponding_Record_Type
5443 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5445 -- Is_Constrained is set according the parent subtype, but is set to
5446 -- False if the derived type is declared with new discriminants.
5450 (Is_Constrained (Parent_Type) or else Constraint_Present)
5451 and then not Present (Discriminant_Specifications (N)));
5453 if Constraint_Present then
5454 if not Has_Discriminants (Parent_Type) then
5455 Error_Msg_N ("untagged parent must have discriminants", N);
5457 elsif Present (Discriminant_Specifications (N)) then
5459 -- Verify that new discriminants are used to constrain old ones
5464 (Constraint (Subtype_Indication (Type_Definition (N)))));
5466 Old_Disc := First_Discriminant (Parent_Type);
5468 while Present (D_Constraint) loop
5469 if Nkind (D_Constraint) /= N_Discriminant_Association then
5471 -- Positional constraint. If it is a reference to a new
5472 -- discriminant, it constrains the corresponding old one.
5474 if Nkind (D_Constraint) = N_Identifier then
5475 New_Disc := First_Discriminant (Derived_Type);
5476 while Present (New_Disc) loop
5477 exit when Chars (New_Disc) = Chars (D_Constraint);
5478 Next_Discriminant (New_Disc);
5481 if Present (New_Disc) then
5482 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5486 Next_Discriminant (Old_Disc);
5488 -- if this is a named constraint, search by name for the old
5489 -- discriminants constrained by the new one.
5491 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5493 -- Find new discriminant with that name
5495 New_Disc := First_Discriminant (Derived_Type);
5496 while Present (New_Disc) loop
5498 Chars (New_Disc) = Chars (Expression (D_Constraint));
5499 Next_Discriminant (New_Disc);
5502 if Present (New_Disc) then
5504 -- Verify that new discriminant renames some discriminant
5505 -- of the parent type, and associate the new discriminant
5506 -- with one or more old ones that it renames.
5512 Selector := First (Selector_Names (D_Constraint));
5513 while Present (Selector) loop
5514 Old_Disc := First_Discriminant (Parent_Type);
5515 while Present (Old_Disc) loop
5516 exit when Chars (Old_Disc) = Chars (Selector);
5517 Next_Discriminant (Old_Disc);
5520 if Present (Old_Disc) then
5521 Set_Corresponding_Discriminant
5522 (New_Disc, Old_Disc);
5531 Next (D_Constraint);
5534 New_Disc := First_Discriminant (Derived_Type);
5535 while Present (New_Disc) loop
5536 if No (Corresponding_Discriminant (New_Disc)) then
5538 ("new discriminant& must constrain old one", N, New_Disc);
5541 Subtypes_Statically_Compatible
5543 Etype (Corresponding_Discriminant (New_Disc)))
5546 ("& not statically compatible with parent discriminant",
5550 Next_Discriminant (New_Disc);
5554 elsif Present (Discriminant_Specifications (N)) then
5556 ("missing discriminant constraint in untagged derivation", N);
5559 -- The entity chain of the derived type includes the new discriminants
5560 -- but shares operations with the parent.
5562 if Present (Discriminant_Specifications (N)) then
5563 Old_Disc := First_Discriminant (Parent_Type);
5564 while Present (Old_Disc) loop
5565 if No (Next_Entity (Old_Disc))
5566 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5569 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5573 Next_Discriminant (Old_Disc);
5577 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5578 if Has_Discriminants (Parent_Type) then
5579 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5580 Set_Discriminant_Constraint (
5581 Derived_Type, Discriminant_Constraint (Parent_Type));
5585 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5587 Set_Has_Completion (Derived_Type);
5589 if Corr_Decl_Needed then
5590 Set_Stored_Constraint (Derived_Type, New_Constraint);
5591 Insert_After (N, Corr_Decl);
5592 Analyze (Corr_Decl);
5593 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5595 end Build_Derived_Concurrent_Type;
5597 ------------------------------------
5598 -- Build_Derived_Enumeration_Type --
5599 ------------------------------------
5601 procedure Build_Derived_Enumeration_Type
5603 Parent_Type : Entity_Id;
5604 Derived_Type : Entity_Id)
5606 Loc : constant Source_Ptr := Sloc (N);
5607 Def : constant Node_Id := Type_Definition (N);
5608 Indic : constant Node_Id := Subtype_Indication (Def);
5609 Implicit_Base : Entity_Id;
5610 Literal : Entity_Id;
5611 New_Lit : Entity_Id;
5612 Literals_List : List_Id;
5613 Type_Decl : Node_Id;
5615 Rang_Expr : Node_Id;
5618 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5619 -- not have explicit literals lists we need to process types derived
5620 -- from them specially. This is handled by Derived_Standard_Character.
5621 -- If the parent type is a generic type, there are no literals either,
5622 -- and we construct the same skeletal representation as for the generic
5625 if Is_Standard_Character_Type (Parent_Type) then
5626 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5628 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5634 if Nkind (Indic) /= N_Subtype_Indication then
5636 Make_Attribute_Reference (Loc,
5637 Attribute_Name => Name_First,
5638 Prefix => New_Reference_To (Derived_Type, Loc));
5639 Set_Etype (Lo, Derived_Type);
5642 Make_Attribute_Reference (Loc,
5643 Attribute_Name => Name_Last,
5644 Prefix => New_Reference_To (Derived_Type, Loc));
5645 Set_Etype (Hi, Derived_Type);
5647 Set_Scalar_Range (Derived_Type,
5653 -- Analyze subtype indication and verify compatibility
5654 -- with parent type.
5656 if Base_Type (Process_Subtype (Indic, N)) /=
5657 Base_Type (Parent_Type)
5660 ("illegal constraint for formal discrete type", N);
5666 -- If a constraint is present, analyze the bounds to catch
5667 -- premature usage of the derived literals.
5669 if Nkind (Indic) = N_Subtype_Indication
5670 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5672 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5673 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5676 -- Introduce an implicit base type for the derived type even if there
5677 -- is no constraint attached to it, since this seems closer to the
5678 -- Ada semantics. Build a full type declaration tree for the derived
5679 -- type using the implicit base type as the defining identifier. The
5680 -- build a subtype declaration tree which applies the constraint (if
5681 -- any) have it replace the derived type declaration.
5683 Literal := First_Literal (Parent_Type);
5684 Literals_List := New_List;
5685 while Present (Literal)
5686 and then Ekind (Literal) = E_Enumeration_Literal
5688 -- Literals of the derived type have the same representation as
5689 -- those of the parent type, but this representation can be
5690 -- overridden by an explicit representation clause. Indicate
5691 -- that there is no explicit representation given yet. These
5692 -- derived literals are implicit operations of the new type,
5693 -- and can be overridden by explicit ones.
5695 if Nkind (Literal) = N_Defining_Character_Literal then
5697 Make_Defining_Character_Literal (Loc, Chars (Literal));
5699 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5702 Set_Ekind (New_Lit, E_Enumeration_Literal);
5703 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5704 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5705 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5706 Set_Alias (New_Lit, Literal);
5707 Set_Is_Known_Valid (New_Lit, True);
5709 Append (New_Lit, Literals_List);
5710 Next_Literal (Literal);
5714 Make_Defining_Identifier (Sloc (Derived_Type),
5715 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5717 -- Indicate the proper nature of the derived type. This must be done
5718 -- before analysis of the literals, to recognize cases when a literal
5719 -- may be hidden by a previous explicit function definition (cf.
5722 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5723 Set_Etype (Derived_Type, Implicit_Base);
5726 Make_Full_Type_Declaration (Loc,
5727 Defining_Identifier => Implicit_Base,
5728 Discriminant_Specifications => No_List,
5730 Make_Enumeration_Type_Definition (Loc, Literals_List));
5732 Mark_Rewrite_Insertion (Type_Decl);
5733 Insert_Before (N, Type_Decl);
5734 Analyze (Type_Decl);
5736 -- After the implicit base is analyzed its Etype needs to be changed
5737 -- to reflect the fact that it is derived from the parent type which
5738 -- was ignored during analysis. We also set the size at this point.
5740 Set_Etype (Implicit_Base, Parent_Type);
5742 Set_Size_Info (Implicit_Base, Parent_Type);
5743 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5744 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5746 -- Copy other flags from parent type
5748 Set_Has_Non_Standard_Rep
5749 (Implicit_Base, Has_Non_Standard_Rep
5751 Set_Has_Pragma_Ordered
5752 (Implicit_Base, Has_Pragma_Ordered
5754 Set_Has_Delayed_Freeze (Implicit_Base);
5756 -- Process the subtype indication including a validation check on the
5757 -- constraint, if any. If a constraint is given, its bounds must be
5758 -- implicitly converted to the new type.
5760 if Nkind (Indic) = N_Subtype_Indication then
5762 R : constant Node_Id :=
5763 Range_Expression (Constraint (Indic));
5766 if Nkind (R) = N_Range then
5767 Hi := Build_Scalar_Bound
5768 (High_Bound (R), Parent_Type, Implicit_Base);
5769 Lo := Build_Scalar_Bound
5770 (Low_Bound (R), Parent_Type, Implicit_Base);
5773 -- Constraint is a Range attribute. Replace with explicit
5774 -- mention of the bounds of the prefix, which must be a
5777 Analyze (Prefix (R));
5779 Convert_To (Implicit_Base,
5780 Make_Attribute_Reference (Loc,
5781 Attribute_Name => Name_Last,
5783 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5786 Convert_To (Implicit_Base,
5787 Make_Attribute_Reference (Loc,
5788 Attribute_Name => Name_First,
5790 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5797 (Type_High_Bound (Parent_Type),
5798 Parent_Type, Implicit_Base);
5801 (Type_Low_Bound (Parent_Type),
5802 Parent_Type, Implicit_Base);
5810 -- If we constructed a default range for the case where no range
5811 -- was given, then the expressions in the range must not freeze
5812 -- since they do not correspond to expressions in the source.
5814 if Nkind (Indic) /= N_Subtype_Indication then
5815 Set_Must_Not_Freeze (Lo);
5816 Set_Must_Not_Freeze (Hi);
5817 Set_Must_Not_Freeze (Rang_Expr);
5821 Make_Subtype_Declaration (Loc,
5822 Defining_Identifier => Derived_Type,
5823 Subtype_Indication =>
5824 Make_Subtype_Indication (Loc,
5825 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5827 Make_Range_Constraint (Loc,
5828 Range_Expression => Rang_Expr))));
5832 -- If pragma Discard_Names applies on the first subtype of the parent
5833 -- type, then it must be applied on this subtype as well.
5835 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5836 Set_Discard_Names (Derived_Type);
5839 -- Apply a range check. Since this range expression doesn't have an
5840 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5843 if Nkind (Indic) = N_Subtype_Indication then
5844 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5846 Source_Typ => Entity (Subtype_Mark (Indic)));
5849 end Build_Derived_Enumeration_Type;
5851 --------------------------------
5852 -- Build_Derived_Numeric_Type --
5853 --------------------------------
5855 procedure Build_Derived_Numeric_Type
5857 Parent_Type : Entity_Id;
5858 Derived_Type : Entity_Id)
5860 Loc : constant Source_Ptr := Sloc (N);
5861 Tdef : constant Node_Id := Type_Definition (N);
5862 Indic : constant Node_Id := Subtype_Indication (Tdef);
5863 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5864 No_Constraint : constant Boolean := Nkind (Indic) /=
5865 N_Subtype_Indication;
5866 Implicit_Base : Entity_Id;
5872 -- Process the subtype indication including a validation check on
5873 -- the constraint if any.
5875 Discard_Node (Process_Subtype (Indic, N));
5877 -- Introduce an implicit base type for the derived type even if there
5878 -- is no constraint attached to it, since this seems closer to the Ada
5882 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5884 Set_Etype (Implicit_Base, Parent_Base);
5885 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5886 Set_Size_Info (Implicit_Base, Parent_Base);
5887 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5888 Set_Parent (Implicit_Base, Parent (Derived_Type));
5889 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5891 -- Set RM Size for discrete type or decimal fixed-point type
5892 -- Ordinary fixed-point is excluded, why???
5894 if Is_Discrete_Type (Parent_Base)
5895 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5897 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5900 Set_Has_Delayed_Freeze (Implicit_Base);
5902 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5903 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5905 Set_Scalar_Range (Implicit_Base,
5910 if Has_Infinities (Parent_Base) then
5911 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5914 -- The Derived_Type, which is the entity of the declaration, is a
5915 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5916 -- absence of an explicit constraint.
5918 Set_Etype (Derived_Type, Implicit_Base);
5920 -- If we did not have a constraint, then the Ekind is set from the
5921 -- parent type (otherwise Process_Subtype has set the bounds)
5923 if No_Constraint then
5924 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5927 -- If we did not have a range constraint, then set the range from the
5928 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5931 or else not Has_Range_Constraint (Indic)
5933 Set_Scalar_Range (Derived_Type,
5935 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5936 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5937 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5939 if Has_Infinities (Parent_Type) then
5940 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5943 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5946 Set_Is_Descendent_Of_Address (Derived_Type,
5947 Is_Descendent_Of_Address (Parent_Type));
5948 Set_Is_Descendent_Of_Address (Implicit_Base,
5949 Is_Descendent_Of_Address (Parent_Type));
5951 -- Set remaining type-specific fields, depending on numeric type
5953 if Is_Modular_Integer_Type (Parent_Type) then
5954 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5956 Set_Non_Binary_Modulus
5957 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5960 (Implicit_Base, Is_Known_Valid (Parent_Base));
5962 elsif Is_Floating_Point_Type (Parent_Type) then
5964 -- Digits of base type is always copied from the digits value of
5965 -- the parent base type, but the digits of the derived type will
5966 -- already have been set if there was a constraint present.
5968 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5969 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
5971 if No_Constraint then
5972 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5975 elsif Is_Fixed_Point_Type (Parent_Type) then
5977 -- Small of base type and derived type are always copied from the
5978 -- parent base type, since smalls never change. The delta of the
5979 -- base type is also copied from the parent base type. However the
5980 -- delta of the derived type will have been set already if a
5981 -- constraint was present.
5983 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5984 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5985 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5987 if No_Constraint then
5988 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
5991 -- The scale and machine radix in the decimal case are always
5992 -- copied from the parent base type.
5994 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
5995 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
5996 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
5998 Set_Machine_Radix_10
5999 (Derived_Type, Machine_Radix_10 (Parent_Base));
6000 Set_Machine_Radix_10
6001 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6003 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6005 if No_Constraint then
6006 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6009 -- the analysis of the subtype_indication sets the
6010 -- digits value of the derived type.
6017 -- The type of the bounds is that of the parent type, and they
6018 -- must be converted to the derived type.
6020 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6022 -- The implicit_base should be frozen when the derived type is frozen,
6023 -- but note that it is used in the conversions of the bounds. For fixed
6024 -- types we delay the determination of the bounds until the proper
6025 -- freezing point. For other numeric types this is rejected by GCC, for
6026 -- reasons that are currently unclear (???), so we choose to freeze the
6027 -- implicit base now. In the case of integers and floating point types
6028 -- this is harmless because subsequent representation clauses cannot
6029 -- affect anything, but it is still baffling that we cannot use the
6030 -- same mechanism for all derived numeric types.
6032 -- There is a further complication: actually *some* representation
6033 -- clauses can affect the implicit base type. Namely, attribute
6034 -- definition clauses for stream-oriented attributes need to set the
6035 -- corresponding TSS entries on the base type, and this normally cannot
6036 -- be done after the base type is frozen, so the circuitry in
6037 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6038 -- not use Set_TSS in this case.
6040 if Is_Fixed_Point_Type (Parent_Type) then
6041 Conditional_Delay (Implicit_Base, Parent_Type);
6043 Freeze_Before (N, Implicit_Base);
6045 end Build_Derived_Numeric_Type;
6047 --------------------------------
6048 -- Build_Derived_Private_Type --
6049 --------------------------------
6051 procedure Build_Derived_Private_Type
6053 Parent_Type : Entity_Id;
6054 Derived_Type : Entity_Id;
6055 Is_Completion : Boolean;
6056 Derive_Subps : Boolean := True)
6058 Loc : constant Source_Ptr := Sloc (N);
6059 Der_Base : Entity_Id;
6061 Full_Decl : Node_Id := Empty;
6062 Full_Der : Entity_Id;
6064 Last_Discr : Entity_Id;
6065 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6066 Swapped : Boolean := False;
6068 procedure Copy_And_Build;
6069 -- Copy derived type declaration, replace parent with its full view,
6070 -- and analyze new declaration.
6072 --------------------
6073 -- Copy_And_Build --
6074 --------------------
6076 procedure Copy_And_Build is
6080 if Ekind (Parent_Type) in Record_Kind
6082 (Ekind (Parent_Type) in Enumeration_Kind
6083 and then not Is_Standard_Character_Type (Parent_Type)
6084 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6086 Full_N := New_Copy_Tree (N);
6087 Insert_After (N, Full_N);
6088 Build_Derived_Type (
6089 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6092 Build_Derived_Type (
6093 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6097 -- Start of processing for Build_Derived_Private_Type
6100 if Is_Tagged_Type (Parent_Type) then
6101 Full_P := Full_View (Parent_Type);
6103 -- A type extension of a type with unknown discriminants is an
6104 -- indefinite type that the back-end cannot handle directly.
6105 -- We treat it as a private type, and build a completion that is
6106 -- derived from the full view of the parent, and hopefully has
6107 -- known discriminants.
6109 -- If the full view of the parent type has an underlying record view,
6110 -- use it to generate the underlying record view of this derived type
6111 -- (required for chains of derivations with unknown discriminants).
6113 -- Minor optimization: we avoid the generation of useless underlying
6114 -- record view entities if the private type declaration has unknown
6115 -- discriminants but its corresponding full view has no
6118 if Has_Unknown_Discriminants (Parent_Type)
6119 and then Present (Full_P)
6120 and then (Has_Discriminants (Full_P)
6121 or else Present (Underlying_Record_View (Full_P)))
6122 and then not In_Open_Scopes (Par_Scope)
6123 and then Expander_Active
6126 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6127 New_Ext : constant Node_Id :=
6129 (Record_Extension_Part (Type_Definition (N)));
6133 Build_Derived_Record_Type
6134 (N, Parent_Type, Derived_Type, Derive_Subps);
6136 -- Build anonymous completion, as a derivation from the full
6137 -- view of the parent. This is not a completion in the usual
6138 -- sense, because the current type is not private.
6141 Make_Full_Type_Declaration (Loc,
6142 Defining_Identifier => Full_Der,
6144 Make_Derived_Type_Definition (Loc,
6145 Subtype_Indication =>
6147 (Subtype_Indication (Type_Definition (N))),
6148 Record_Extension_Part => New_Ext));
6150 -- If the parent type has an underlying record view, use it
6151 -- here to build the new underlying record view.
6153 if Present (Underlying_Record_View (Full_P)) then
6155 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6157 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6158 Underlying_Record_View (Full_P));
6161 Install_Private_Declarations (Par_Scope);
6162 Install_Visible_Declarations (Par_Scope);
6163 Insert_Before (N, Decl);
6165 -- Mark entity as an underlying record view before analysis,
6166 -- to avoid generating the list of its primitive operations
6167 -- (which is not really required for this entity) and thus
6168 -- prevent spurious errors associated with missing overriding
6169 -- of abstract primitives (overridden only for Derived_Type).
6171 Set_Ekind (Full_Der, E_Record_Type);
6172 Set_Is_Underlying_Record_View (Full_Der);
6176 pragma Assert (Has_Discriminants (Full_Der)
6177 and then not Has_Unknown_Discriminants (Full_Der));
6179 Uninstall_Declarations (Par_Scope);
6181 -- Freeze the underlying record view, to prevent generation of
6182 -- useless dispatching information, which is simply shared with
6183 -- the real derived type.
6185 Set_Is_Frozen (Full_Der);
6187 -- Set up links between real entity and underlying record view
6189 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6190 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6193 -- If discriminants are known, build derived record
6196 Build_Derived_Record_Type
6197 (N, Parent_Type, Derived_Type, Derive_Subps);
6202 elsif Has_Discriminants (Parent_Type) then
6203 if Present (Full_View (Parent_Type)) then
6204 if not Is_Completion then
6206 -- Copy declaration for subsequent analysis, to provide a
6207 -- completion for what is a private declaration. Indicate that
6208 -- the full type is internally generated.
6210 Full_Decl := New_Copy_Tree (N);
6211 Full_Der := New_Copy (Derived_Type);
6212 Set_Comes_From_Source (Full_Decl, False);
6213 Set_Comes_From_Source (Full_Der, False);
6214 Set_Parent (Full_Der, Full_Decl);
6216 Insert_After (N, Full_Decl);
6219 -- If this is a completion, the full view being built is itself
6220 -- private. We build a subtype of the parent with the same
6221 -- constraints as this full view, to convey to the back end the
6222 -- constrained components and the size of this subtype. If the
6223 -- parent is constrained, its full view can serve as the
6224 -- underlying full view of the derived type.
6226 if No (Discriminant_Specifications (N)) then
6227 if Nkind (Subtype_Indication (Type_Definition (N))) =
6228 N_Subtype_Indication
6230 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6232 elsif Is_Constrained (Full_View (Parent_Type)) then
6233 Set_Underlying_Full_View
6234 (Derived_Type, Full_View (Parent_Type));
6238 -- If there are new discriminants, the parent subtype is
6239 -- constrained by them, but it is not clear how to build
6240 -- the Underlying_Full_View in this case???
6247 -- Build partial view of derived type from partial view of parent
6249 Build_Derived_Record_Type
6250 (N, Parent_Type, Derived_Type, Derive_Subps);
6252 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6253 if not In_Open_Scopes (Par_Scope)
6254 or else not In_Same_Source_Unit (N, Parent_Type)
6256 -- Swap partial and full views temporarily
6258 Install_Private_Declarations (Par_Scope);
6259 Install_Visible_Declarations (Par_Scope);
6263 -- Build full view of derived type from full view of parent which
6264 -- is now installed. Subprograms have been derived on the partial
6265 -- view, the completion does not derive them anew.
6267 if not Is_Tagged_Type (Parent_Type) then
6269 -- If the parent is itself derived from another private type,
6270 -- installing the private declarations has not affected its
6271 -- privacy status, so use its own full view explicitly.
6273 if Is_Private_Type (Parent_Type) then
6274 Build_Derived_Record_Type
6275 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6277 Build_Derived_Record_Type
6278 (Full_Decl, Parent_Type, Full_Der, False);
6282 -- If full view of parent is tagged, the completion inherits
6283 -- the proper primitive operations.
6285 Set_Defining_Identifier (Full_Decl, Full_Der);
6286 Build_Derived_Record_Type
6287 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6290 -- The full declaration has been introduced into the tree and
6291 -- processed in the step above. It should not be analyzed again
6292 -- (when encountered later in the current list of declarations)
6293 -- to prevent spurious name conflicts. The full entity remains
6296 Set_Analyzed (Full_Decl);
6299 Uninstall_Declarations (Par_Scope);
6301 if In_Open_Scopes (Par_Scope) then
6302 Install_Visible_Declarations (Par_Scope);
6306 Der_Base := Base_Type (Derived_Type);
6307 Set_Full_View (Derived_Type, Full_Der);
6308 Set_Full_View (Der_Base, Base_Type (Full_Der));
6310 -- Copy the discriminant list from full view to the partial views
6311 -- (base type and its subtype). Gigi requires that the partial and
6312 -- full views have the same discriminants.
6314 -- Note that since the partial view is pointing to discriminants
6315 -- in the full view, their scope will be that of the full view.
6316 -- This might cause some front end problems and need adjustment???
6318 Discr := First_Discriminant (Base_Type (Full_Der));
6319 Set_First_Entity (Der_Base, Discr);
6322 Last_Discr := Discr;
6323 Next_Discriminant (Discr);
6324 exit when No (Discr);
6327 Set_Last_Entity (Der_Base, Last_Discr);
6329 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6330 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6331 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6334 -- If this is a completion, the derived type stays private and
6335 -- there is no need to create a further full view, except in the
6336 -- unusual case when the derivation is nested within a child unit,
6342 elsif Present (Full_View (Parent_Type))
6343 and then Has_Discriminants (Full_View (Parent_Type))
6345 if Has_Unknown_Discriminants (Parent_Type)
6346 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6347 N_Subtype_Indication
6350 ("cannot constrain type with unknown discriminants",
6351 Subtype_Indication (Type_Definition (N)));
6355 -- If full view of parent is a record type, build full view as a
6356 -- derivation from the parent's full view. Partial view remains
6357 -- private. For code generation and linking, the full view must have
6358 -- the same public status as the partial one. This full view is only
6359 -- needed if the parent type is in an enclosing scope, so that the
6360 -- full view may actually become visible, e.g. in a child unit. This
6361 -- is both more efficient, and avoids order of freezing problems with
6362 -- the added entities.
6364 if not Is_Private_Type (Full_View (Parent_Type))
6365 and then (In_Open_Scopes (Scope (Parent_Type)))
6368 Make_Defining_Identifier
6369 (Sloc (Derived_Type), Chars (Derived_Type));
6370 Set_Is_Itype (Full_Der);
6371 Set_Has_Private_Declaration (Full_Der);
6372 Set_Has_Private_Declaration (Derived_Type);
6373 Set_Associated_Node_For_Itype (Full_Der, N);
6374 Set_Parent (Full_Der, Parent (Derived_Type));
6375 Set_Full_View (Derived_Type, Full_Der);
6376 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6377 Full_P := Full_View (Parent_Type);
6378 Exchange_Declarations (Parent_Type);
6380 Exchange_Declarations (Full_P);
6383 Build_Derived_Record_Type
6384 (N, Full_View (Parent_Type), Derived_Type,
6385 Derive_Subps => False);
6388 -- In any case, the primitive operations are inherited from the
6389 -- parent type, not from the internal full view.
6391 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6393 if Derive_Subps then
6394 Derive_Subprograms (Parent_Type, Derived_Type);
6398 -- Untagged type, No discriminants on either view
6400 if Nkind (Subtype_Indication (Type_Definition (N))) =
6401 N_Subtype_Indication
6404 ("illegal constraint on type without discriminants", N);
6407 if Present (Discriminant_Specifications (N))
6408 and then Present (Full_View (Parent_Type))
6409 and then not Is_Tagged_Type (Full_View (Parent_Type))
6411 Error_Msg_N ("cannot add discriminants to untagged type", N);
6414 Set_Stored_Constraint (Derived_Type, No_Elist);
6415 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6416 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6417 Set_Has_Controlled_Component
6418 (Derived_Type, Has_Controlled_Component
6421 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6423 if not Is_Controlled (Parent_Type) then
6424 Set_Finalize_Storage_Only
6425 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6428 -- Construct the implicit full view by deriving from full view of the
6429 -- parent type. In order to get proper visibility, we install the
6430 -- parent scope and its declarations.
6432 -- ??? If the parent is untagged private and its completion is
6433 -- tagged, this mechanism will not work because we cannot derive from
6434 -- the tagged full view unless we have an extension.
6436 if Present (Full_View (Parent_Type))
6437 and then not Is_Tagged_Type (Full_View (Parent_Type))
6438 and then not Is_Completion
6441 Make_Defining_Identifier
6442 (Sloc (Derived_Type), Chars (Derived_Type));
6443 Set_Is_Itype (Full_Der);
6444 Set_Has_Private_Declaration (Full_Der);
6445 Set_Has_Private_Declaration (Derived_Type);
6446 Set_Associated_Node_For_Itype (Full_Der, N);
6447 Set_Parent (Full_Der, Parent (Derived_Type));
6448 Set_Full_View (Derived_Type, Full_Der);
6450 if not In_Open_Scopes (Par_Scope) then
6451 Install_Private_Declarations (Par_Scope);
6452 Install_Visible_Declarations (Par_Scope);
6454 Uninstall_Declarations (Par_Scope);
6456 -- If parent scope is open and in another unit, and parent has a
6457 -- completion, then the derivation is taking place in the visible
6458 -- part of a child unit. In that case retrieve the full view of
6459 -- the parent momentarily.
6461 elsif not In_Same_Source_Unit (N, Parent_Type) then
6462 Full_P := Full_View (Parent_Type);
6463 Exchange_Declarations (Parent_Type);
6465 Exchange_Declarations (Full_P);
6467 -- Otherwise it is a local derivation
6473 Set_Scope (Full_Der, Current_Scope);
6474 Set_Is_First_Subtype (Full_Der,
6475 Is_First_Subtype (Derived_Type));
6476 Set_Has_Size_Clause (Full_Der, False);
6477 Set_Has_Alignment_Clause (Full_Der, False);
6478 Set_Next_Entity (Full_Der, Empty);
6479 Set_Has_Delayed_Freeze (Full_Der);
6480 Set_Is_Frozen (Full_Der, False);
6481 Set_Freeze_Node (Full_Der, Empty);
6482 Set_Depends_On_Private (Full_Der,
6483 Has_Private_Component (Full_Der));
6484 Set_Public_Status (Full_Der);
6488 Set_Has_Unknown_Discriminants (Derived_Type,
6489 Has_Unknown_Discriminants (Parent_Type));
6491 if Is_Private_Type (Derived_Type) then
6492 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6495 if Is_Private_Type (Parent_Type)
6496 and then Base_Type (Parent_Type) = Parent_Type
6497 and then In_Open_Scopes (Scope (Parent_Type))
6499 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6501 if Is_Child_Unit (Scope (Current_Scope))
6502 and then Is_Completion
6503 and then In_Private_Part (Current_Scope)
6504 and then Scope (Parent_Type) /= Current_Scope
6506 -- This is the unusual case where a type completed by a private
6507 -- derivation occurs within a package nested in a child unit, and
6508 -- the parent is declared in an ancestor. In this case, the full
6509 -- view of the parent type will become visible in the body of
6510 -- the enclosing child, and only then will the current type be
6511 -- possibly non-private. We build a underlying full view that
6512 -- will be installed when the enclosing child body is compiled.
6515 Make_Defining_Identifier
6516 (Sloc (Derived_Type), Chars (Derived_Type));
6517 Set_Is_Itype (Full_Der);
6518 Build_Itype_Reference (Full_Der, N);
6520 -- The full view will be used to swap entities on entry/exit to
6521 -- the body, and must appear in the entity list for the package.
6523 Append_Entity (Full_Der, Scope (Derived_Type));
6524 Set_Has_Private_Declaration (Full_Der);
6525 Set_Has_Private_Declaration (Derived_Type);
6526 Set_Associated_Node_For_Itype (Full_Der, N);
6527 Set_Parent (Full_Der, Parent (Derived_Type));
6528 Full_P := Full_View (Parent_Type);
6529 Exchange_Declarations (Parent_Type);
6531 Exchange_Declarations (Full_P);
6532 Set_Underlying_Full_View (Derived_Type, Full_Der);
6535 end Build_Derived_Private_Type;
6537 -------------------------------
6538 -- Build_Derived_Record_Type --
6539 -------------------------------
6543 -- Ideally we would like to use the same model of type derivation for
6544 -- tagged and untagged record types. Unfortunately this is not quite
6545 -- possible because the semantics of representation clauses is different
6546 -- for tagged and untagged records under inheritance. Consider the
6549 -- type R (...) is [tagged] record ... end record;
6550 -- type T (...) is new R (...) [with ...];
6552 -- The representation clauses for T can specify a completely different
6553 -- record layout from R's. Hence the same component can be placed in two
6554 -- very different positions in objects of type T and R. If R and T are
6555 -- tagged types, representation clauses for T can only specify the layout
6556 -- of non inherited components, thus components that are common in R and T
6557 -- have the same position in objects of type R and T.
6559 -- This has two implications. The first is that the entire tree for R's
6560 -- declaration needs to be copied for T in the untagged case, so that T
6561 -- can be viewed as a record type of its own with its own representation
6562 -- clauses. The second implication is the way we handle discriminants.
6563 -- Specifically, in the untagged case we need a way to communicate to Gigi
6564 -- what are the real discriminants in the record, while for the semantics
6565 -- we need to consider those introduced by the user to rename the
6566 -- discriminants in the parent type. This is handled by introducing the
6567 -- notion of stored discriminants. See below for more.
6569 -- Fortunately the way regular components are inherited can be handled in
6570 -- the same way in tagged and untagged types.
6572 -- To complicate things a bit more the private view of a private extension
6573 -- cannot be handled in the same way as the full view (for one thing the
6574 -- semantic rules are somewhat different). We will explain what differs
6577 -- 2. DISCRIMINANTS UNDER INHERITANCE
6579 -- The semantic rules governing the discriminants of derived types are
6582 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6583 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6585 -- If parent type has discriminants, then the discriminants that are
6586 -- declared in the derived type are [3.4 (11)]:
6588 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6591 -- o Otherwise, each discriminant of the parent type (implicitly declared
6592 -- in the same order with the same specifications). In this case, the
6593 -- discriminants are said to be "inherited", or if unknown in the parent
6594 -- are also unknown in the derived type.
6596 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6598 -- o The parent subtype shall be constrained;
6600 -- o If the parent type is not a tagged type, then each discriminant of
6601 -- the derived type shall be used in the constraint defining a parent
6602 -- subtype. [Implementation note: This ensures that the new discriminant
6603 -- can share storage with an existing discriminant.]
6605 -- For the derived type each discriminant of the parent type is either
6606 -- inherited, constrained to equal some new discriminant of the derived
6607 -- type, or constrained to the value of an expression.
6609 -- When inherited or constrained to equal some new discriminant, the
6610 -- parent discriminant and the discriminant of the derived type are said
6613 -- If a discriminant of the parent type is constrained to a specific value
6614 -- in the derived type definition, then the discriminant is said to be
6615 -- "specified" by that derived type definition.
6617 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6619 -- We have spoken about stored discriminants in point 1 (introduction)
6620 -- above. There are two sort of stored discriminants: implicit and
6621 -- explicit. As long as the derived type inherits the same discriminants as
6622 -- the root record type, stored discriminants are the same as regular
6623 -- discriminants, and are said to be implicit. However, if any discriminant
6624 -- in the root type was renamed in the derived type, then the derived
6625 -- type will contain explicit stored discriminants. Explicit stored
6626 -- discriminants are discriminants in addition to the semantically visible
6627 -- discriminants defined for the derived type. Stored discriminants are
6628 -- used by Gigi to figure out what are the physical discriminants in
6629 -- objects of the derived type (see precise definition in einfo.ads).
6630 -- As an example, consider the following:
6632 -- type R (D1, D2, D3 : Int) is record ... end record;
6633 -- type T1 is new R;
6634 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6635 -- type T3 is new T2;
6636 -- type T4 (Y : Int) is new T3 (Y, 99);
6638 -- The following table summarizes the discriminants and stored
6639 -- discriminants in R and T1 through T4.
6641 -- Type Discrim Stored Discrim Comment
6642 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6643 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6644 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6645 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6646 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6648 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6649 -- find the corresponding discriminant in the parent type, while
6650 -- Original_Record_Component (abbreviated ORC below), the actual physical
6651 -- component that is renamed. Finally the field Is_Completely_Hidden
6652 -- (abbreviated ICH below) is set for all explicit stored discriminants
6653 -- (see einfo.ads for more info). For the above example this gives:
6655 -- Discrim CD ORC ICH
6656 -- ^^^^^^^ ^^ ^^^ ^^^
6657 -- D1 in R empty itself no
6658 -- D2 in R empty itself no
6659 -- D3 in R empty itself no
6661 -- D1 in T1 D1 in R itself no
6662 -- D2 in T1 D2 in R itself no
6663 -- D3 in T1 D3 in R itself no
6665 -- X1 in T2 D3 in T1 D3 in T2 no
6666 -- X2 in T2 D1 in T1 D1 in T2 no
6667 -- D1 in T2 empty itself yes
6668 -- D2 in T2 empty itself yes
6669 -- D3 in T2 empty itself yes
6671 -- X1 in T3 X1 in T2 D3 in T3 no
6672 -- X2 in T3 X2 in T2 D1 in T3 no
6673 -- D1 in T3 empty itself yes
6674 -- D2 in T3 empty itself yes
6675 -- D3 in T3 empty itself yes
6677 -- Y in T4 X1 in T3 D3 in T3 no
6678 -- D1 in T3 empty itself yes
6679 -- D2 in T3 empty itself yes
6680 -- D3 in T3 empty itself yes
6682 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6684 -- Type derivation for tagged types is fairly straightforward. If no
6685 -- discriminants are specified by the derived type, these are inherited
6686 -- from the parent. No explicit stored discriminants are ever necessary.
6687 -- The only manipulation that is done to the tree is that of adding a
6688 -- _parent field with parent type and constrained to the same constraint
6689 -- specified for the parent in the derived type definition. For instance:
6691 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6692 -- type T1 is new R with null record;
6693 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6695 -- are changed into:
6697 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6698 -- _parent : R (D1, D2, D3);
6701 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6702 -- _parent : T1 (X2, 88, X1);
6705 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6706 -- ORC and ICH fields are:
6708 -- Discrim CD ORC ICH
6709 -- ^^^^^^^ ^^ ^^^ ^^^
6710 -- D1 in R empty itself no
6711 -- D2 in R empty itself no
6712 -- D3 in R empty itself no
6714 -- D1 in T1 D1 in R D1 in R no
6715 -- D2 in T1 D2 in R D2 in R no
6716 -- D3 in T1 D3 in R D3 in R no
6718 -- X1 in T2 D3 in T1 D3 in R no
6719 -- X2 in T2 D1 in T1 D1 in R no
6721 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6723 -- Regardless of whether we dealing with a tagged or untagged type
6724 -- we will transform all derived type declarations of the form
6726 -- type T is new R (...) [with ...];
6728 -- subtype S is R (...);
6729 -- type T is new S [with ...];
6731 -- type BT is new R [with ...];
6732 -- subtype T is BT (...);
6734 -- That is, the base derived type is constrained only if it has no
6735 -- discriminants. The reason for doing this is that GNAT's semantic model
6736 -- assumes that a base type with discriminants is unconstrained.
6738 -- Note that, strictly speaking, the above transformation is not always
6739 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6741 -- procedure B34011A is
6742 -- type REC (D : integer := 0) is record
6747 -- type T6 is new Rec;
6748 -- function F return T6;
6753 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6756 -- The definition of Q6.U is illegal. However transforming Q6.U into
6758 -- type BaseU is new T6;
6759 -- subtype U is BaseU (Q6.F.I)
6761 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6762 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6763 -- the transformation described above.
6765 -- There is another instance where the above transformation is incorrect.
6769 -- type Base (D : Integer) is tagged null record;
6770 -- procedure P (X : Base);
6772 -- type Der is new Base (2) with null record;
6773 -- procedure P (X : Der);
6776 -- Then the above transformation turns this into
6778 -- type Der_Base is new Base with null record;
6779 -- -- procedure P (X : Base) is implicitly inherited here
6780 -- -- as procedure P (X : Der_Base).
6782 -- subtype Der is Der_Base (2);
6783 -- procedure P (X : Der);
6784 -- -- The overriding of P (X : Der_Base) is illegal since we
6785 -- -- have a parameter conformance problem.
6787 -- To get around this problem, after having semantically processed Der_Base
6788 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6789 -- Discriminant_Constraint from Der so that when parameter conformance is
6790 -- checked when P is overridden, no semantic errors are flagged.
6792 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6794 -- Regardless of whether we are dealing with a tagged or untagged type
6795 -- we will transform all derived type declarations of the form
6797 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6798 -- type T is new R [with ...];
6800 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6802 -- The reason for such transformation is that it allows us to implement a
6803 -- very clean form of component inheritance as explained below.
6805 -- Note that this transformation is not achieved by direct tree rewriting
6806 -- and manipulation, but rather by redoing the semantic actions that the
6807 -- above transformation will entail. This is done directly in routine
6808 -- Inherit_Components.
6810 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6812 -- In both tagged and untagged derived types, regular non discriminant
6813 -- components are inherited in the derived type from the parent type. In
6814 -- the absence of discriminants component, inheritance is straightforward
6815 -- as components can simply be copied from the parent.
6817 -- If the parent has discriminants, inheriting components constrained with
6818 -- these discriminants requires caution. Consider the following example:
6820 -- type R (D1, D2 : Positive) is [tagged] record
6821 -- S : String (D1 .. D2);
6824 -- type T1 is new R [with null record];
6825 -- type T2 (X : positive) is new R (1, X) [with null record];
6827 -- As explained in 6. above, T1 is rewritten as
6828 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6829 -- which makes the treatment for T1 and T2 identical.
6831 -- What we want when inheriting S, is that references to D1 and D2 in R are
6832 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6833 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6834 -- with either discriminant references in the derived type or expressions.
6835 -- This replacement is achieved as follows: before inheriting R's
6836 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6837 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6838 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6839 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6840 -- by String (1 .. X).
6842 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6844 -- We explain here the rules governing private type extensions relevant to
6845 -- type derivation. These rules are explained on the following example:
6847 -- type D [(...)] is new A [(...)] with private; <-- partial view
6848 -- type D [(...)] is new P [(...)] with null record; <-- full view
6850 -- Type A is called the ancestor subtype of the private extension.
6851 -- Type P is the parent type of the full view of the private extension. It
6852 -- must be A or a type derived from A.
6854 -- The rules concerning the discriminants of private type extensions are
6857 -- o If a private extension inherits known discriminants from the ancestor
6858 -- subtype, then the full view shall also inherit its discriminants from
6859 -- the ancestor subtype and the parent subtype of the full view shall be
6860 -- constrained if and only if the ancestor subtype is constrained.
6862 -- o If a partial view has unknown discriminants, then the full view may
6863 -- define a definite or an indefinite subtype, with or without
6866 -- o If a partial view has neither known nor unknown discriminants, then
6867 -- the full view shall define a definite subtype.
6869 -- o If the ancestor subtype of a private extension has constrained
6870 -- discriminants, then the parent subtype of the full view shall impose a
6871 -- statically matching constraint on those discriminants.
6873 -- This means that only the following forms of private extensions are
6876 -- type D is new A with private; <-- partial view
6877 -- type D is new P with null record; <-- full view
6879 -- If A has no discriminants than P has no discriminants, otherwise P must
6880 -- inherit A's discriminants.
6882 -- type D is new A (...) with private; <-- partial view
6883 -- type D is new P (:::) with null record; <-- full view
6885 -- P must inherit A's discriminants and (...) and (:::) must statically
6888 -- subtype A is R (...);
6889 -- type D is new A with private; <-- partial view
6890 -- type D is new P with null record; <-- full view
6892 -- P must have inherited R's discriminants and must be derived from A or
6893 -- any of its subtypes.
6895 -- type D (..) is new A with private; <-- partial view
6896 -- type D (..) is new P [(:::)] with null record; <-- full view
6898 -- No specific constraints on P's discriminants or constraint (:::).
6899 -- Note that A can be unconstrained, but the parent subtype P must either
6900 -- be constrained or (:::) must be present.
6902 -- type D (..) is new A [(...)] with private; <-- partial view
6903 -- type D (..) is new P [(:::)] with null record; <-- full view
6905 -- P's constraints on A's discriminants must statically match those
6906 -- imposed by (...).
6908 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6910 -- The full view of a private extension is handled exactly as described
6911 -- above. The model chose for the private view of a private extension is
6912 -- the same for what concerns discriminants (i.e. they receive the same
6913 -- treatment as in the tagged case). However, the private view of the
6914 -- private extension always inherits the components of the parent base,
6915 -- without replacing any discriminant reference. Strictly speaking this is
6916 -- incorrect. However, Gigi never uses this view to generate code so this
6917 -- is a purely semantic issue. In theory, a set of transformations similar
6918 -- to those given in 5. and 6. above could be applied to private views of
6919 -- private extensions to have the same model of component inheritance as
6920 -- for non private extensions. However, this is not done because it would
6921 -- further complicate private type processing. Semantically speaking, this
6922 -- leaves us in an uncomfortable situation. As an example consider:
6925 -- type R (D : integer) is tagged record
6926 -- S : String (1 .. D);
6928 -- procedure P (X : R);
6929 -- type T is new R (1) with private;
6931 -- type T is new R (1) with null record;
6934 -- This is transformed into:
6937 -- type R (D : integer) is tagged record
6938 -- S : String (1 .. D);
6940 -- procedure P (X : R);
6941 -- type T is new R (1) with private;
6943 -- type BaseT is new R with null record;
6944 -- subtype T is BaseT (1);
6947 -- (strictly speaking the above is incorrect Ada)
6949 -- From the semantic standpoint the private view of private extension T
6950 -- should be flagged as constrained since one can clearly have
6954 -- in a unit withing Pack. However, when deriving subprograms for the
6955 -- private view of private extension T, T must be seen as unconstrained
6956 -- since T has discriminants (this is a constraint of the current
6957 -- subprogram derivation model). Thus, when processing the private view of
6958 -- a private extension such as T, we first mark T as unconstrained, we
6959 -- process it, we perform program derivation and just before returning from
6960 -- Build_Derived_Record_Type we mark T as constrained.
6962 -- ??? Are there are other uncomfortable cases that we will have to
6965 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6967 -- Types that are derived from a visible record type and have a private
6968 -- extension present other peculiarities. They behave mostly like private
6969 -- types, but if they have primitive operations defined, these will not
6970 -- have the proper signatures for further inheritance, because other
6971 -- primitive operations will use the implicit base that we define for
6972 -- private derivations below. This affect subprogram inheritance (see
6973 -- Derive_Subprograms for details). We also derive the implicit base from
6974 -- the base type of the full view, so that the implicit base is a record
6975 -- type and not another private type, This avoids infinite loops.
6977 procedure Build_Derived_Record_Type
6979 Parent_Type : Entity_Id;
6980 Derived_Type : Entity_Id;
6981 Derive_Subps : Boolean := True)
6983 Loc : constant Source_Ptr := Sloc (N);
6984 Parent_Base : Entity_Id;
6987 Discrim : Entity_Id;
6988 Last_Discrim : Entity_Id;
6991 Discs : Elist_Id := New_Elmt_List;
6992 -- An empty Discs list means that there were no constraints in the
6993 -- subtype indication or that there was an error processing it.
6995 Assoc_List : Elist_Id;
6996 New_Discrs : Elist_Id;
6997 New_Base : Entity_Id;
6999 New_Indic : Node_Id;
7001 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7002 Discriminant_Specs : constant Boolean :=
7003 Present (Discriminant_Specifications (N));
7004 Private_Extension : constant Boolean :=
7005 Nkind (N) = N_Private_Extension_Declaration;
7007 Constraint_Present : Boolean;
7008 Inherit_Discrims : Boolean := False;
7009 Save_Etype : Entity_Id;
7010 Save_Discr_Constr : Elist_Id;
7011 Save_Next_Entity : Entity_Id;
7014 if Ekind (Parent_Type) = E_Record_Type_With_Private
7015 and then Present (Full_View (Parent_Type))
7016 and then Has_Discriminants (Parent_Type)
7018 Parent_Base := Base_Type (Full_View (Parent_Type));
7020 Parent_Base := Base_Type (Parent_Type);
7023 -- Before we start the previously documented transformations, here is
7024 -- little fix for size and alignment of tagged types. Normally when we
7025 -- derive type D from type P, we copy the size and alignment of P as the
7026 -- default for D, and in the absence of explicit representation clauses
7027 -- for D, the size and alignment are indeed the same as the parent.
7029 -- But this is wrong for tagged types, since fields may be added, and
7030 -- the default size may need to be larger, and the default alignment may
7031 -- need to be larger.
7033 -- We therefore reset the size and alignment fields in the tagged case.
7034 -- Note that the size and alignment will in any case be at least as
7035 -- large as the parent type (since the derived type has a copy of the
7036 -- parent type in the _parent field)
7038 -- The type is also marked as being tagged here, which is needed when
7039 -- processing components with a self-referential anonymous access type
7040 -- in the call to Check_Anonymous_Access_Components below. Note that
7041 -- this flag is also set later on for completeness.
7044 Set_Is_Tagged_Type (Derived_Type);
7045 Init_Size_Align (Derived_Type);
7048 -- STEP 0a: figure out what kind of derived type declaration we have
7050 if Private_Extension then
7052 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7055 Type_Def := Type_Definition (N);
7057 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7058 -- Parent_Base can be a private type or private extension. However,
7059 -- for tagged types with an extension the newly added fields are
7060 -- visible and hence the Derived_Type is always an E_Record_Type.
7061 -- (except that the parent may have its own private fields).
7062 -- For untagged types we preserve the Ekind of the Parent_Base.
7064 if Present (Record_Extension_Part (Type_Def)) then
7065 Set_Ekind (Derived_Type, E_Record_Type);
7067 -- Create internal access types for components with anonymous
7070 if Ada_Version >= Ada_2005 then
7071 Check_Anonymous_Access_Components
7072 (N, Derived_Type, Derived_Type,
7073 Component_List (Record_Extension_Part (Type_Def)));
7077 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7081 -- Indic can either be an N_Identifier if the subtype indication
7082 -- contains no constraint or an N_Subtype_Indication if the subtype
7083 -- indication has a constraint.
7085 Indic := Subtype_Indication (Type_Def);
7086 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7088 -- Check that the type has visible discriminants. The type may be
7089 -- a private type with unknown discriminants whose full view has
7090 -- discriminants which are invisible.
7092 if Constraint_Present then
7093 if not Has_Discriminants (Parent_Base)
7095 (Has_Unknown_Discriminants (Parent_Base)
7096 and then Is_Private_Type (Parent_Base))
7099 ("invalid constraint: type has no discriminant",
7100 Constraint (Indic));
7102 Constraint_Present := False;
7103 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7105 elsif Is_Constrained (Parent_Type) then
7107 ("invalid constraint: parent type is already constrained",
7108 Constraint (Indic));
7110 Constraint_Present := False;
7111 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7115 -- STEP 0b: If needed, apply transformation given in point 5. above
7117 if not Private_Extension
7118 and then Has_Discriminants (Parent_Type)
7119 and then not Discriminant_Specs
7120 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7122 -- First, we must analyze the constraint (see comment in point 5.)
7124 if Constraint_Present then
7125 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7127 if Has_Discriminants (Derived_Type)
7128 and then Has_Private_Declaration (Derived_Type)
7129 and then Present (Discriminant_Constraint (Derived_Type))
7131 -- Verify that constraints of the full view statically match
7132 -- those given in the partial view.
7138 C1 := First_Elmt (New_Discrs);
7139 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7140 while Present (C1) and then Present (C2) loop
7141 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7143 (Is_OK_Static_Expression (Node (C1))
7145 Is_OK_Static_Expression (Node (C2))
7147 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7153 "constraint not conformant to previous declaration",
7164 -- Insert and analyze the declaration for the unconstrained base type
7166 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7169 Make_Full_Type_Declaration (Loc,
7170 Defining_Identifier => New_Base,
7172 Make_Derived_Type_Definition (Loc,
7173 Abstract_Present => Abstract_Present (Type_Def),
7174 Limited_Present => Limited_Present (Type_Def),
7175 Subtype_Indication =>
7176 New_Occurrence_Of (Parent_Base, Loc),
7177 Record_Extension_Part =>
7178 Relocate_Node (Record_Extension_Part (Type_Def)),
7179 Interface_List => Interface_List (Type_Def)));
7181 Set_Parent (New_Decl, Parent (N));
7182 Mark_Rewrite_Insertion (New_Decl);
7183 Insert_Before (N, New_Decl);
7185 -- In the extension case, make sure ancestor is frozen appropriately
7186 -- (see also non-discriminated case below).
7188 if Present (Record_Extension_Part (Type_Def))
7189 or else Is_Interface (Parent_Base)
7191 Freeze_Before (New_Decl, Parent_Type);
7194 -- Note that this call passes False for the Derive_Subps parameter
7195 -- because subprogram derivation is deferred until after creating
7196 -- the subtype (see below).
7199 (New_Decl, Parent_Base, New_Base,
7200 Is_Completion => True, Derive_Subps => False);
7202 -- ??? This needs re-examination to determine whether the
7203 -- above call can simply be replaced by a call to Analyze.
7205 Set_Analyzed (New_Decl);
7207 -- Insert and analyze the declaration for the constrained subtype
7209 if Constraint_Present then
7211 Make_Subtype_Indication (Loc,
7212 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7213 Constraint => Relocate_Node (Constraint (Indic)));
7217 Constr_List : constant List_Id := New_List;
7222 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7223 while Present (C) loop
7226 -- It is safe here to call New_Copy_Tree since
7227 -- Force_Evaluation was called on each constraint in
7228 -- Build_Discriminant_Constraints.
7230 Append (New_Copy_Tree (Expr), To => Constr_List);
7236 Make_Subtype_Indication (Loc,
7237 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7239 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7244 Make_Subtype_Declaration (Loc,
7245 Defining_Identifier => Derived_Type,
7246 Subtype_Indication => New_Indic));
7250 -- Derivation of subprograms must be delayed until the full subtype
7251 -- has been established, to ensure proper overriding of subprograms
7252 -- inherited by full types. If the derivations occurred as part of
7253 -- the call to Build_Derived_Type above, then the check for type
7254 -- conformance would fail because earlier primitive subprograms
7255 -- could still refer to the full type prior the change to the new
7256 -- subtype and hence would not match the new base type created here.
7257 -- Subprograms are not derived, however, when Derive_Subps is False
7258 -- (since otherwise there could be redundant derivations).
7260 if Derive_Subps then
7261 Derive_Subprograms (Parent_Type, Derived_Type);
7264 -- For tagged types the Discriminant_Constraint of the new base itype
7265 -- is inherited from the first subtype so that no subtype conformance
7266 -- problem arise when the first subtype overrides primitive
7267 -- operations inherited by the implicit base type.
7270 Set_Discriminant_Constraint
7271 (New_Base, Discriminant_Constraint (Derived_Type));
7277 -- If we get here Derived_Type will have no discriminants or it will be
7278 -- a discriminated unconstrained base type.
7280 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7284 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7285 -- The declaration of a specific descendant of an interface type
7286 -- freezes the interface type (RM 13.14).
7288 if not Private_Extension or else Is_Interface (Parent_Base) then
7289 Freeze_Before (N, Parent_Type);
7292 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7293 -- cannot be declared at a deeper level than its parent type is
7294 -- removed. The check on derivation within a generic body is also
7295 -- relaxed, but there's a restriction that a derived tagged type
7296 -- cannot be declared in a generic body if it's derived directly
7297 -- or indirectly from a formal type of that generic.
7299 if Ada_Version >= Ada_2005 then
7300 if Present (Enclosing_Generic_Body (Derived_Type)) then
7302 Ancestor_Type : Entity_Id;
7305 -- Check to see if any ancestor of the derived type is a
7308 Ancestor_Type := Parent_Type;
7309 while not Is_Generic_Type (Ancestor_Type)
7310 and then Etype (Ancestor_Type) /= Ancestor_Type
7312 Ancestor_Type := Etype (Ancestor_Type);
7315 -- If the derived type does have a formal type as an
7316 -- ancestor, then it's an error if the derived type is
7317 -- declared within the body of the generic unit that
7318 -- declares the formal type in its generic formal part. It's
7319 -- sufficient to check whether the ancestor type is declared
7320 -- inside the same generic body as the derived type (such as
7321 -- within a nested generic spec), in which case the
7322 -- derivation is legal. If the formal type is declared
7323 -- outside of that generic body, then it's guaranteed that
7324 -- the derived type is declared within the generic body of
7325 -- the generic unit declaring the formal type.
7327 if Is_Generic_Type (Ancestor_Type)
7328 and then Enclosing_Generic_Body (Ancestor_Type) /=
7329 Enclosing_Generic_Body (Derived_Type)
7332 ("parent type of& must not be descendant of formal type"
7333 & " of an enclosing generic body",
7334 Indic, Derived_Type);
7339 elsif Type_Access_Level (Derived_Type) /=
7340 Type_Access_Level (Parent_Type)
7341 and then not Is_Generic_Type (Derived_Type)
7343 if Is_Controlled (Parent_Type) then
7345 ("controlled type must be declared at the library level",
7349 ("type extension at deeper accessibility level than parent",
7355 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7359 and then GB /= Enclosing_Generic_Body (Parent_Base)
7362 ("parent type of& must not be outside generic body"
7364 Indic, Derived_Type);
7370 -- Ada 2005 (AI-251)
7372 if Ada_Version >= Ada_2005 and then Is_Tagged then
7374 -- "The declaration of a specific descendant of an interface type
7375 -- freezes the interface type" (RM 13.14).
7380 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7381 Iface := First (Interface_List (Type_Def));
7382 while Present (Iface) loop
7383 Freeze_Before (N, Etype (Iface));
7390 -- STEP 1b : preliminary cleanup of the full view of private types
7392 -- If the type is already marked as having discriminants, then it's the
7393 -- completion of a private type or private extension and we need to
7394 -- retain the discriminants from the partial view if the current
7395 -- declaration has Discriminant_Specifications so that we can verify
7396 -- conformance. However, we must remove any existing components that
7397 -- were inherited from the parent (and attached in Copy_And_Swap)
7398 -- because the full type inherits all appropriate components anyway, and
7399 -- we do not want the partial view's components interfering.
7401 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7402 Discrim := First_Discriminant (Derived_Type);
7404 Last_Discrim := Discrim;
7405 Next_Discriminant (Discrim);
7406 exit when No (Discrim);
7409 Set_Last_Entity (Derived_Type, Last_Discrim);
7411 -- In all other cases wipe out the list of inherited components (even
7412 -- inherited discriminants), it will be properly rebuilt here.
7415 Set_First_Entity (Derived_Type, Empty);
7416 Set_Last_Entity (Derived_Type, Empty);
7419 -- STEP 1c: Initialize some flags for the Derived_Type
7421 -- The following flags must be initialized here so that
7422 -- Process_Discriminants can check that discriminants of tagged types do
7423 -- not have a default initial value and that access discriminants are
7424 -- only specified for limited records. For completeness, these flags are
7425 -- also initialized along with all the other flags below.
7427 -- AI-419: Limitedness is not inherited from an interface parent, so to
7428 -- be limited in that case the type must be explicitly declared as
7429 -- limited. However, task and protected interfaces are always limited.
7431 if Limited_Present (Type_Def) then
7432 Set_Is_Limited_Record (Derived_Type);
7434 elsif Is_Limited_Record (Parent_Type)
7435 or else (Present (Full_View (Parent_Type))
7436 and then Is_Limited_Record (Full_View (Parent_Type)))
7438 if not Is_Interface (Parent_Type)
7439 or else Is_Synchronized_Interface (Parent_Type)
7440 or else Is_Protected_Interface (Parent_Type)
7441 or else Is_Task_Interface (Parent_Type)
7443 Set_Is_Limited_Record (Derived_Type);
7447 -- STEP 2a: process discriminants of derived type if any
7449 Push_Scope (Derived_Type);
7451 if Discriminant_Specs then
7452 Set_Has_Unknown_Discriminants (Derived_Type, False);
7454 -- The following call initializes fields Has_Discriminants and
7455 -- Discriminant_Constraint, unless we are processing the completion
7456 -- of a private type declaration.
7458 Check_Or_Process_Discriminants (N, Derived_Type);
7460 -- For untagged types, the constraint on the Parent_Type must be
7461 -- present and is used to rename the discriminants.
7463 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7464 Error_Msg_N ("untagged parent must have discriminants", Indic);
7466 elsif not Is_Tagged and then not Constraint_Present then
7468 ("discriminant constraint needed for derived untagged records",
7471 -- Otherwise the parent subtype must be constrained unless we have a
7472 -- private extension.
7474 elsif not Constraint_Present
7475 and then not Private_Extension
7476 and then not Is_Constrained (Parent_Type)
7479 ("unconstrained type not allowed in this context", Indic);
7481 elsif Constraint_Present then
7482 -- The following call sets the field Corresponding_Discriminant
7483 -- for the discriminants in the Derived_Type.
7485 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7487 -- For untagged types all new discriminants must rename
7488 -- discriminants in the parent. For private extensions new
7489 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7491 Discrim := First_Discriminant (Derived_Type);
7492 while Present (Discrim) loop
7494 and then No (Corresponding_Discriminant (Discrim))
7497 ("new discriminants must constrain old ones", Discrim);
7499 elsif Private_Extension
7500 and then Present (Corresponding_Discriminant (Discrim))
7503 ("only static constraints allowed for parent"
7504 & " discriminants in the partial view", Indic);
7508 -- If a new discriminant is used in the constraint, then its
7509 -- subtype must be statically compatible with the parent
7510 -- discriminant's subtype (3.7(15)).
7512 if Present (Corresponding_Discriminant (Discrim))
7514 not Subtypes_Statically_Compatible
7516 Etype (Corresponding_Discriminant (Discrim)))
7519 ("subtype must be compatible with parent discriminant",
7523 Next_Discriminant (Discrim);
7526 -- Check whether the constraints of the full view statically
7527 -- match those imposed by the parent subtype [7.3(13)].
7529 if Present (Stored_Constraint (Derived_Type)) then
7534 C1 := First_Elmt (Discs);
7535 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7536 while Present (C1) and then Present (C2) loop
7538 Fully_Conformant_Expressions (Node (C1), Node (C2))
7541 ("not conformant with previous declaration",
7552 -- STEP 2b: No new discriminants, inherit discriminants if any
7555 if Private_Extension then
7556 Set_Has_Unknown_Discriminants
7558 Has_Unknown_Discriminants (Parent_Type)
7559 or else Unknown_Discriminants_Present (N));
7561 -- The partial view of the parent may have unknown discriminants,
7562 -- but if the full view has discriminants and the parent type is
7563 -- in scope they must be inherited.
7565 elsif Has_Unknown_Discriminants (Parent_Type)
7567 (not Has_Discriminants (Parent_Type)
7568 or else not In_Open_Scopes (Scope (Parent_Type)))
7570 Set_Has_Unknown_Discriminants (Derived_Type);
7573 if not Has_Unknown_Discriminants (Derived_Type)
7574 and then not Has_Unknown_Discriminants (Parent_Base)
7575 and then Has_Discriminants (Parent_Type)
7577 Inherit_Discrims := True;
7578 Set_Has_Discriminants
7579 (Derived_Type, True);
7580 Set_Discriminant_Constraint
7581 (Derived_Type, Discriminant_Constraint (Parent_Base));
7584 -- The following test is true for private types (remember
7585 -- transformation 5. is not applied to those) and in an error
7588 if Constraint_Present then
7589 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7592 -- For now mark a new derived type as constrained only if it has no
7593 -- discriminants. At the end of Build_Derived_Record_Type we properly
7594 -- set this flag in the case of private extensions. See comments in
7595 -- point 9. just before body of Build_Derived_Record_Type.
7599 not (Inherit_Discrims
7600 or else Has_Unknown_Discriminants (Derived_Type)));
7603 -- STEP 3: initialize fields of derived type
7605 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7606 Set_Stored_Constraint (Derived_Type, No_Elist);
7608 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7609 -- but cannot be interfaces
7611 if not Private_Extension
7612 and then Ekind (Derived_Type) /= E_Private_Type
7613 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7615 if Interface_Present (Type_Def) then
7616 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7619 Set_Interfaces (Derived_Type, No_Elist);
7622 -- Fields inherited from the Parent_Type
7625 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7626 Set_Has_Specified_Layout
7627 (Derived_Type, Has_Specified_Layout (Parent_Type));
7628 Set_Is_Limited_Composite
7629 (Derived_Type, Is_Limited_Composite (Parent_Type));
7630 Set_Is_Private_Composite
7631 (Derived_Type, Is_Private_Composite (Parent_Type));
7633 -- Fields inherited from the Parent_Base
7635 Set_Has_Controlled_Component
7636 (Derived_Type, Has_Controlled_Component (Parent_Base));
7637 Set_Has_Non_Standard_Rep
7638 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7639 Set_Has_Primitive_Operations
7640 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7642 -- Fields inherited from the Parent_Base in the non-private case
7644 if Ekind (Derived_Type) = E_Record_Type then
7645 Set_Has_Complex_Representation
7646 (Derived_Type, Has_Complex_Representation (Parent_Base));
7649 -- Fields inherited from the Parent_Base for record types
7651 if Is_Record_Type (Derived_Type) then
7653 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7654 -- Parent_Base can be a private type or private extension.
7656 if Present (Full_View (Parent_Base)) then
7657 Set_OK_To_Reorder_Components
7659 OK_To_Reorder_Components (Full_View (Parent_Base)));
7660 Set_Reverse_Bit_Order
7661 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7663 Set_OK_To_Reorder_Components
7664 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7665 Set_Reverse_Bit_Order
7666 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7670 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7672 if not Is_Controlled (Parent_Type) then
7673 Set_Finalize_Storage_Only
7674 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7677 -- Set fields for private derived types
7679 if Is_Private_Type (Derived_Type) then
7680 Set_Depends_On_Private (Derived_Type, True);
7681 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7683 -- Inherit fields from non private record types. If this is the
7684 -- completion of a derivation from a private type, the parent itself
7685 -- is private, and the attributes come from its full view, which must
7689 if Is_Private_Type (Parent_Base)
7690 and then not Is_Record_Type (Parent_Base)
7692 Set_Component_Alignment
7693 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7695 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7697 Set_Component_Alignment
7698 (Derived_Type, Component_Alignment (Parent_Base));
7700 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7704 -- Set fields for tagged types
7707 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7709 -- All tagged types defined in Ada.Finalization are controlled
7711 if Chars (Scope (Derived_Type)) = Name_Finalization
7712 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7713 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7715 Set_Is_Controlled (Derived_Type);
7717 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7720 -- Minor optimization: there is no need to generate the class-wide
7721 -- entity associated with an underlying record view.
7723 if not Is_Underlying_Record_View (Derived_Type) then
7724 Make_Class_Wide_Type (Derived_Type);
7727 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7729 if Has_Discriminants (Derived_Type)
7730 and then Constraint_Present
7732 Set_Stored_Constraint
7733 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7736 if Ada_Version >= Ada_2005 then
7738 Ifaces_List : Elist_Id;
7741 -- Checks rules 3.9.4 (13/2 and 14/2)
7743 if Comes_From_Source (Derived_Type)
7744 and then not Is_Private_Type (Derived_Type)
7745 and then Is_Interface (Parent_Type)
7746 and then not Is_Interface (Derived_Type)
7748 if Is_Task_Interface (Parent_Type) then
7750 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7753 elsif Is_Protected_Interface (Parent_Type) then
7755 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7760 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7762 Check_Interfaces (N, Type_Def);
7764 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7765 -- not already in the parents.
7769 Ifaces_List => Ifaces_List,
7770 Exclude_Parents => True);
7772 Set_Interfaces (Derived_Type, Ifaces_List);
7774 -- If the derived type is the anonymous type created for
7775 -- a declaration whose parent has a constraint, propagate
7776 -- the interface list to the source type. This must be done
7777 -- prior to the completion of the analysis of the source type
7778 -- because the components in the extension may contain current
7779 -- instances whose legality depends on some ancestor.
7781 if Is_Itype (Derived_Type) then
7783 Def : constant Node_Id :=
7784 Associated_Node_For_Itype (Derived_Type);
7787 and then Nkind (Def) = N_Full_Type_Declaration
7790 (Defining_Identifier (Def), Ifaces_List);
7798 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7799 Set_Has_Non_Standard_Rep
7800 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7803 -- STEP 4: Inherit components from the parent base and constrain them.
7804 -- Apply the second transformation described in point 6. above.
7806 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7807 or else not Has_Discriminants (Parent_Type)
7808 or else not Is_Constrained (Parent_Type)
7812 Constrs := Discriminant_Constraint (Parent_Type);
7817 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7819 -- STEP 5a: Copy the parent record declaration for untagged types
7821 if not Is_Tagged then
7823 -- Discriminant_Constraint (Derived_Type) has been properly
7824 -- constructed. Save it and temporarily set it to Empty because we
7825 -- do not want the call to New_Copy_Tree below to mess this list.
7827 if Has_Discriminants (Derived_Type) then
7828 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7829 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7831 Save_Discr_Constr := No_Elist;
7834 -- Save the Etype field of Derived_Type. It is correctly set now,
7835 -- but the call to New_Copy tree may remap it to point to itself,
7836 -- which is not what we want. Ditto for the Next_Entity field.
7838 Save_Etype := Etype (Derived_Type);
7839 Save_Next_Entity := Next_Entity (Derived_Type);
7841 -- Assoc_List maps all stored discriminants in the Parent_Base to
7842 -- stored discriminants in the Derived_Type. It is fundamental that
7843 -- no types or itypes with discriminants other than the stored
7844 -- discriminants appear in the entities declared inside
7845 -- Derived_Type, since the back end cannot deal with it.
7849 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7851 -- Restore the fields saved prior to the New_Copy_Tree call
7852 -- and compute the stored constraint.
7854 Set_Etype (Derived_Type, Save_Etype);
7855 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7857 if Has_Discriminants (Derived_Type) then
7858 Set_Discriminant_Constraint
7859 (Derived_Type, Save_Discr_Constr);
7860 Set_Stored_Constraint
7861 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7862 Replace_Components (Derived_Type, New_Decl);
7865 -- Insert the new derived type declaration
7867 Rewrite (N, New_Decl);
7869 -- STEP 5b: Complete the processing for record extensions in generics
7871 -- There is no completion for record extensions declared in the
7872 -- parameter part of a generic, so we need to complete processing for
7873 -- these generic record extensions here. The Record_Type_Definition call
7874 -- will change the Ekind of the components from E_Void to E_Component.
7876 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7877 Record_Type_Definition (Empty, Derived_Type);
7879 -- STEP 5c: Process the record extension for non private tagged types
7881 elsif not Private_Extension then
7883 -- Add the _parent field in the derived type
7885 Expand_Record_Extension (Derived_Type, Type_Def);
7887 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7888 -- implemented interfaces if we are in expansion mode
7891 and then Has_Interfaces (Derived_Type)
7893 Add_Interface_Tag_Components (N, Derived_Type);
7896 -- Analyze the record extension
7898 Record_Type_Definition
7899 (Record_Extension_Part (Type_Def), Derived_Type);
7904 -- Nothing else to do if there is an error in the derivation.
7905 -- An unusual case: the full view may be derived from a type in an
7906 -- instance, when the partial view was used illegally as an actual
7907 -- in that instance, leading to a circular definition.
7909 if Etype (Derived_Type) = Any_Type
7910 or else Etype (Parent_Type) = Derived_Type
7915 -- Set delayed freeze and then derive subprograms, we need to do
7916 -- this in this order so that derived subprograms inherit the
7917 -- derived freeze if necessary.
7919 Set_Has_Delayed_Freeze (Derived_Type);
7921 if Derive_Subps then
7922 Derive_Subprograms (Parent_Type, Derived_Type);
7925 -- If we have a private extension which defines a constrained derived
7926 -- type mark as constrained here after we have derived subprograms. See
7927 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7929 if Private_Extension and then Inherit_Discrims then
7930 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7931 Set_Is_Constrained (Derived_Type, True);
7932 Set_Discriminant_Constraint (Derived_Type, Discs);
7934 elsif Is_Constrained (Parent_Type) then
7936 (Derived_Type, True);
7937 Set_Discriminant_Constraint
7938 (Derived_Type, Discriminant_Constraint (Parent_Type));
7942 -- Update the class-wide type, which shares the now-completed entity
7943 -- list with its specific type. In case of underlying record views,
7944 -- we do not generate the corresponding class wide entity.
7947 and then not Is_Underlying_Record_View (Derived_Type)
7950 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7952 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7955 -- Update the scope of anonymous access types of discriminants and other
7956 -- components, to prevent scope anomalies in gigi, when the derivation
7957 -- appears in a scope nested within that of the parent.
7963 D := First_Entity (Derived_Type);
7964 while Present (D) loop
7965 if Ekind_In (D, E_Discriminant, E_Component) then
7966 if Is_Itype (Etype (D))
7967 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7969 Set_Scope (Etype (D), Current_Scope);
7976 end Build_Derived_Record_Type;
7978 ------------------------
7979 -- Build_Derived_Type --
7980 ------------------------
7982 procedure Build_Derived_Type
7984 Parent_Type : Entity_Id;
7985 Derived_Type : Entity_Id;
7986 Is_Completion : Boolean;
7987 Derive_Subps : Boolean := True)
7989 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7992 -- Set common attributes
7994 Set_Scope (Derived_Type, Current_Scope);
7996 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7997 Set_Etype (Derived_Type, Parent_Base);
7998 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8000 Set_Size_Info (Derived_Type, Parent_Type);
8001 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8002 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8003 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8005 -- If the parent type is a private subtype, the convention on the base
8006 -- type may be set in the private part, and not propagated to the
8007 -- subtype until later, so we obtain the convention from the base type.
8009 Set_Convention (Derived_Type, Convention (Parent_Base));
8011 -- Propagate invariant information. The new type has invariants if
8012 -- they are inherited from the parent type, and these invariants can
8013 -- be further inherited, so both flags are set.
8015 if Has_Inheritable_Invariants (Parent_Type) then
8016 Set_Has_Inheritable_Invariants (Derived_Type);
8017 Set_Has_Invariants (Derived_Type);
8020 -- We similarly inherit predicates
8022 if Has_Predicates (Parent_Type) then
8023 Set_Has_Predicates (Derived_Type);
8026 -- The derived type inherits the representation clauses of the parent.
8027 -- However, for a private type that is completed by a derivation, there
8028 -- may be operation attributes that have been specified already (stream
8029 -- attributes and External_Tag) and those must be provided. Finally,
8030 -- if the partial view is a private extension, the representation items
8031 -- of the parent have been inherited already, and should not be chained
8032 -- twice to the derived type.
8034 if Is_Tagged_Type (Parent_Type)
8035 and then Present (First_Rep_Item (Derived_Type))
8037 -- The existing items are either operational items or items inherited
8038 -- from a private extension declaration.
8042 -- Used to iterate over representation items of the derived type
8045 -- Last representation item of the (non-empty) representation
8046 -- item list of the derived type.
8048 Found : Boolean := False;
8051 Rep := First_Rep_Item (Derived_Type);
8053 while Present (Rep) loop
8054 if Rep = First_Rep_Item (Parent_Type) then
8059 Rep := Next_Rep_Item (Rep);
8061 if Present (Rep) then
8067 -- Here if we either encountered the parent type's first rep
8068 -- item on the derived type's rep item list (in which case
8069 -- Found is True, and we have nothing else to do), or if we
8070 -- reached the last rep item of the derived type, which is
8071 -- Last_Rep, in which case we further chain the parent type's
8072 -- rep items to those of the derived type.
8075 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8080 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8083 case Ekind (Parent_Type) is
8084 when Numeric_Kind =>
8085 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8088 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8092 | Class_Wide_Kind =>
8093 Build_Derived_Record_Type
8094 (N, Parent_Type, Derived_Type, Derive_Subps);
8097 when Enumeration_Kind =>
8098 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8101 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8103 when Incomplete_Or_Private_Kind =>
8104 Build_Derived_Private_Type
8105 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8107 -- For discriminated types, the derivation includes deriving
8108 -- primitive operations. For others it is done below.
8110 if Is_Tagged_Type (Parent_Type)
8111 or else Has_Discriminants (Parent_Type)
8112 or else (Present (Full_View (Parent_Type))
8113 and then Has_Discriminants (Full_View (Parent_Type)))
8118 when Concurrent_Kind =>
8119 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8122 raise Program_Error;
8125 if Etype (Derived_Type) = Any_Type then
8129 -- Set delayed freeze and then derive subprograms, we need to do this
8130 -- in this order so that derived subprograms inherit the derived freeze
8133 Set_Has_Delayed_Freeze (Derived_Type);
8134 if Derive_Subps then
8135 Derive_Subprograms (Parent_Type, Derived_Type);
8138 Set_Has_Primitive_Operations
8139 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8140 end Build_Derived_Type;
8142 -----------------------
8143 -- Build_Discriminal --
8144 -----------------------
8146 procedure Build_Discriminal (Discrim : Entity_Id) is
8147 D_Minal : Entity_Id;
8148 CR_Disc : Entity_Id;
8151 -- A discriminal has the same name as the discriminant
8153 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8155 Set_Ekind (D_Minal, E_In_Parameter);
8156 Set_Mechanism (D_Minal, Default_Mechanism);
8157 Set_Etype (D_Minal, Etype (Discrim));
8158 Set_Scope (D_Minal, Current_Scope);
8160 Set_Discriminal (Discrim, D_Minal);
8161 Set_Discriminal_Link (D_Minal, Discrim);
8163 -- For task types, build at once the discriminants of the corresponding
8164 -- record, which are needed if discriminants are used in entry defaults
8165 -- and in family bounds.
8167 if Is_Concurrent_Type (Current_Scope)
8168 or else Is_Limited_Type (Current_Scope)
8170 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8172 Set_Ekind (CR_Disc, E_In_Parameter);
8173 Set_Mechanism (CR_Disc, Default_Mechanism);
8174 Set_Etype (CR_Disc, Etype (Discrim));
8175 Set_Scope (CR_Disc, Current_Scope);
8176 Set_Discriminal_Link (CR_Disc, Discrim);
8177 Set_CR_Discriminant (Discrim, CR_Disc);
8179 end Build_Discriminal;
8181 ------------------------------------
8182 -- Build_Discriminant_Constraints --
8183 ------------------------------------
8185 function Build_Discriminant_Constraints
8188 Derived_Def : Boolean := False) return Elist_Id
8190 C : constant Node_Id := Constraint (Def);
8191 Nb_Discr : constant Nat := Number_Discriminants (T);
8193 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8194 -- Saves the expression corresponding to a given discriminant in T
8196 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8197 -- Return the Position number within array Discr_Expr of a discriminant
8198 -- D within the discriminant list of the discriminated type T.
8204 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8208 Disc := First_Discriminant (T);
8209 for J in Discr_Expr'Range loop
8214 Next_Discriminant (Disc);
8217 -- Note: Since this function is called on discriminants that are
8218 -- known to belong to the discriminated type, falling through the
8219 -- loop with no match signals an internal compiler error.
8221 raise Program_Error;
8224 -- Declarations local to Build_Discriminant_Constraints
8228 Elist : constant Elist_Id := New_Elmt_List;
8236 Discrim_Present : Boolean := False;
8238 -- Start of processing for Build_Discriminant_Constraints
8241 -- The following loop will process positional associations only.
8242 -- For a positional association, the (single) discriminant is
8243 -- implicitly specified by position, in textual order (RM 3.7.2).
8245 Discr := First_Discriminant (T);
8246 Constr := First (Constraints (C));
8247 for D in Discr_Expr'Range loop
8248 exit when Nkind (Constr) = N_Discriminant_Association;
8251 Error_Msg_N ("too few discriminants given in constraint", C);
8252 return New_Elmt_List;
8254 elsif Nkind (Constr) = N_Range
8255 or else (Nkind (Constr) = N_Attribute_Reference
8257 Attribute_Name (Constr) = Name_Range)
8260 ("a range is not a valid discriminant constraint", Constr);
8261 Discr_Expr (D) := Error;
8264 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8265 Discr_Expr (D) := Constr;
8268 Next_Discriminant (Discr);
8272 if No (Discr) and then Present (Constr) then
8273 Error_Msg_N ("too many discriminants given in constraint", Constr);
8274 return New_Elmt_List;
8277 -- Named associations can be given in any order, but if both positional
8278 -- and named associations are used in the same discriminant constraint,
8279 -- then positional associations must occur first, at their normal
8280 -- position. Hence once a named association is used, the rest of the
8281 -- discriminant constraint must use only named associations.
8283 while Present (Constr) loop
8285 -- Positional association forbidden after a named association
8287 if Nkind (Constr) /= N_Discriminant_Association then
8288 Error_Msg_N ("positional association follows named one", Constr);
8289 return New_Elmt_List;
8291 -- Otherwise it is a named association
8294 -- E records the type of the discriminants in the named
8295 -- association. All the discriminants specified in the same name
8296 -- association must have the same type.
8300 -- Search the list of discriminants in T to see if the simple name
8301 -- given in the constraint matches any of them.
8303 Id := First (Selector_Names (Constr));
8304 while Present (Id) loop
8307 -- If Original_Discriminant is present, we are processing a
8308 -- generic instantiation and this is an instance node. We need
8309 -- to find the name of the corresponding discriminant in the
8310 -- actual record type T and not the name of the discriminant in
8311 -- the generic formal. Example:
8314 -- type G (D : int) is private;
8316 -- subtype W is G (D => 1);
8318 -- type Rec (X : int) is record ... end record;
8319 -- package Q is new P (G => Rec);
8321 -- At the point of the instantiation, formal type G is Rec
8322 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8323 -- which really looks like "subtype W is Rec (D => 1);" at
8324 -- the point of instantiation, we want to find the discriminant
8325 -- that corresponds to D in Rec, i.e. X.
8327 if Present (Original_Discriminant (Id))
8328 and then In_Instance
8330 Discr := Find_Corresponding_Discriminant (Id, T);
8334 Discr := First_Discriminant (T);
8335 while Present (Discr) loop
8336 if Chars (Discr) = Chars (Id) then
8341 Next_Discriminant (Discr);
8345 Error_Msg_N ("& does not match any discriminant", Id);
8346 return New_Elmt_List;
8348 -- The following is only useful for the benefit of generic
8349 -- instances but it does not interfere with other
8350 -- processing for the non-generic case so we do it in all
8351 -- cases (for generics this statement is executed when
8352 -- processing the generic definition, see comment at the
8353 -- beginning of this if statement).
8356 Set_Original_Discriminant (Id, Discr);
8360 Position := Pos_Of_Discr (T, Discr);
8362 if Present (Discr_Expr (Position)) then
8363 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8366 -- Each discriminant specified in the same named association
8367 -- must be associated with a separate copy of the
8368 -- corresponding expression.
8370 if Present (Next (Id)) then
8371 Expr := New_Copy_Tree (Expression (Constr));
8372 Set_Parent (Expr, Parent (Expression (Constr)));
8374 Expr := Expression (Constr);
8377 Discr_Expr (Position) := Expr;
8378 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8381 -- A discriminant association with more than one discriminant
8382 -- name is only allowed if the named discriminants are all of
8383 -- the same type (RM 3.7.1(8)).
8386 E := Base_Type (Etype (Discr));
8388 elsif Base_Type (Etype (Discr)) /= E then
8390 ("all discriminants in an association " &
8391 "must have the same type", Id);
8401 -- A discriminant constraint must provide exactly one value for each
8402 -- discriminant of the type (RM 3.7.1(8)).
8404 for J in Discr_Expr'Range loop
8405 if No (Discr_Expr (J)) then
8406 Error_Msg_N ("too few discriminants given in constraint", C);
8407 return New_Elmt_List;
8411 -- Determine if there are discriminant expressions in the constraint
8413 for J in Discr_Expr'Range loop
8414 if Denotes_Discriminant
8415 (Discr_Expr (J), Check_Concurrent => True)
8417 Discrim_Present := True;
8421 -- Build an element list consisting of the expressions given in the
8422 -- discriminant constraint and apply the appropriate checks. The list
8423 -- is constructed after resolving any named discriminant associations
8424 -- and therefore the expressions appear in the textual order of the
8427 Discr := First_Discriminant (T);
8428 for J in Discr_Expr'Range loop
8429 if Discr_Expr (J) /= Error then
8430 Append_Elmt (Discr_Expr (J), Elist);
8432 -- If any of the discriminant constraints is given by a
8433 -- discriminant and we are in a derived type declaration we
8434 -- have a discriminant renaming. Establish link between new
8435 -- and old discriminant.
8437 if Denotes_Discriminant (Discr_Expr (J)) then
8439 Set_Corresponding_Discriminant
8440 (Entity (Discr_Expr (J)), Discr);
8443 -- Force the evaluation of non-discriminant expressions.
8444 -- If we have found a discriminant in the constraint 3.4(26)
8445 -- and 3.8(18) demand that no range checks are performed are
8446 -- after evaluation. If the constraint is for a component
8447 -- definition that has a per-object constraint, expressions are
8448 -- evaluated but not checked either. In all other cases perform
8452 if Discrim_Present then
8455 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8457 Has_Per_Object_Constraint
8458 (Defining_Identifier (Parent (Parent (Def))))
8462 elsif Is_Access_Type (Etype (Discr)) then
8463 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8466 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8469 Force_Evaluation (Discr_Expr (J));
8472 -- Check that the designated type of an access discriminant's
8473 -- expression is not a class-wide type unless the discriminant's
8474 -- designated type is also class-wide.
8476 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8477 and then not Is_Class_Wide_Type
8478 (Designated_Type (Etype (Discr)))
8479 and then Etype (Discr_Expr (J)) /= Any_Type
8480 and then Is_Class_Wide_Type
8481 (Designated_Type (Etype (Discr_Expr (J))))
8483 Wrong_Type (Discr_Expr (J), Etype (Discr));
8485 elsif Is_Access_Type (Etype (Discr))
8486 and then not Is_Access_Constant (Etype (Discr))
8487 and then Is_Access_Type (Etype (Discr_Expr (J)))
8488 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8491 ("constraint for discriminant& must be access to variable",
8496 Next_Discriminant (Discr);
8500 end Build_Discriminant_Constraints;
8502 ---------------------------------
8503 -- Build_Discriminated_Subtype --
8504 ---------------------------------
8506 procedure Build_Discriminated_Subtype
8510 Related_Nod : Node_Id;
8511 For_Access : Boolean := False)
8513 Has_Discrs : constant Boolean := Has_Discriminants (T);
8514 Constrained : constant Boolean :=
8516 and then not Is_Empty_Elmt_List (Elist)
8517 and then not Is_Class_Wide_Type (T))
8518 or else Is_Constrained (T);
8521 if Ekind (T) = E_Record_Type then
8523 Set_Ekind (Def_Id, E_Private_Subtype);
8524 Set_Is_For_Access_Subtype (Def_Id, True);
8526 Set_Ekind (Def_Id, E_Record_Subtype);
8529 -- Inherit preelaboration flag from base, for types for which it
8530 -- may have been set: records, private types, protected types.
8532 Set_Known_To_Have_Preelab_Init
8533 (Def_Id, Known_To_Have_Preelab_Init (T));
8535 elsif Ekind (T) = E_Task_Type then
8536 Set_Ekind (Def_Id, E_Task_Subtype);
8538 elsif Ekind (T) = E_Protected_Type then
8539 Set_Ekind (Def_Id, E_Protected_Subtype);
8540 Set_Known_To_Have_Preelab_Init
8541 (Def_Id, Known_To_Have_Preelab_Init (T));
8543 elsif Is_Private_Type (T) then
8544 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8545 Set_Known_To_Have_Preelab_Init
8546 (Def_Id, Known_To_Have_Preelab_Init (T));
8548 elsif Is_Class_Wide_Type (T) then
8549 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8552 -- Incomplete type. Attach subtype to list of dependents, to be
8553 -- completed with full view of parent type, unless is it the
8554 -- designated subtype of a record component within an init_proc.
8555 -- This last case arises for a component of an access type whose
8556 -- designated type is incomplete (e.g. a Taft Amendment type).
8557 -- The designated subtype is within an inner scope, and needs no
8558 -- elaboration, because only the access type is needed in the
8559 -- initialization procedure.
8561 Set_Ekind (Def_Id, Ekind (T));
8563 if For_Access and then Within_Init_Proc then
8566 Append_Elmt (Def_Id, Private_Dependents (T));
8570 Set_Etype (Def_Id, T);
8571 Init_Size_Align (Def_Id);
8572 Set_Has_Discriminants (Def_Id, Has_Discrs);
8573 Set_Is_Constrained (Def_Id, Constrained);
8575 Set_First_Entity (Def_Id, First_Entity (T));
8576 Set_Last_Entity (Def_Id, Last_Entity (T));
8578 -- If the subtype is the completion of a private declaration, there may
8579 -- have been representation clauses for the partial view, and they must
8580 -- be preserved. Build_Derived_Type chains the inherited clauses with
8581 -- the ones appearing on the extension. If this comes from a subtype
8582 -- declaration, all clauses are inherited.
8584 if No (First_Rep_Item (Def_Id)) then
8585 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8588 if Is_Tagged_Type (T) then
8589 Set_Is_Tagged_Type (Def_Id);
8590 Make_Class_Wide_Type (Def_Id);
8593 Set_Stored_Constraint (Def_Id, No_Elist);
8596 Set_Discriminant_Constraint (Def_Id, Elist);
8597 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8600 if Is_Tagged_Type (T) then
8602 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8603 -- concurrent record type (which has the list of primitive
8606 if Ada_Version >= Ada_2005
8607 and then Is_Concurrent_Type (T)
8609 Set_Corresponding_Record_Type (Def_Id,
8610 Corresponding_Record_Type (T));
8612 Set_Direct_Primitive_Operations (Def_Id,
8613 Direct_Primitive_Operations (T));
8616 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8619 -- Subtypes introduced by component declarations do not need to be
8620 -- marked as delayed, and do not get freeze nodes, because the semantics
8621 -- verifies that the parents of the subtypes are frozen before the
8622 -- enclosing record is frozen.
8624 if not Is_Type (Scope (Def_Id)) then
8625 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8627 if Is_Private_Type (T)
8628 and then Present (Full_View (T))
8630 Conditional_Delay (Def_Id, Full_View (T));
8632 Conditional_Delay (Def_Id, T);
8636 if Is_Record_Type (T) then
8637 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8640 and then not Is_Empty_Elmt_List (Elist)
8641 and then not For_Access
8643 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8644 elsif not For_Access then
8645 Set_Cloned_Subtype (Def_Id, T);
8648 end Build_Discriminated_Subtype;
8650 ---------------------------
8651 -- Build_Itype_Reference --
8652 ---------------------------
8654 procedure Build_Itype_Reference
8658 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8661 -- Itype references are only created for use by the back-end
8663 if Inside_A_Generic then
8666 Set_Itype (IR, Ityp);
8667 Insert_After (Nod, IR);
8669 end Build_Itype_Reference;
8671 ------------------------
8672 -- Build_Scalar_Bound --
8673 ------------------------
8675 function Build_Scalar_Bound
8678 Der_T : Entity_Id) return Node_Id
8680 New_Bound : Entity_Id;
8683 -- Note: not clear why this is needed, how can the original bound
8684 -- be unanalyzed at this point? and if it is, what business do we
8685 -- have messing around with it? and why is the base type of the
8686 -- parent type the right type for the resolution. It probably is
8687 -- not! It is OK for the new bound we are creating, but not for
8688 -- the old one??? Still if it never happens, no problem!
8690 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8692 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8693 New_Bound := New_Copy (Bound);
8694 Set_Etype (New_Bound, Der_T);
8695 Set_Analyzed (New_Bound);
8697 elsif Is_Entity_Name (Bound) then
8698 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8700 -- The following is almost certainly wrong. What business do we have
8701 -- relocating a node (Bound) that is presumably still attached to
8702 -- the tree elsewhere???
8705 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8708 Set_Etype (New_Bound, Der_T);
8710 end Build_Scalar_Bound;
8712 --------------------------------
8713 -- Build_Underlying_Full_View --
8714 --------------------------------
8716 procedure Build_Underlying_Full_View
8721 Loc : constant Source_Ptr := Sloc (N);
8722 Subt : constant Entity_Id :=
8723 Make_Defining_Identifier
8724 (Loc, New_External_Name (Chars (Typ), 'S'));
8731 procedure Set_Discriminant_Name (Id : Node_Id);
8732 -- If the derived type has discriminants, they may rename discriminants
8733 -- of the parent. When building the full view of the parent, we need to
8734 -- recover the names of the original discriminants if the constraint is
8735 -- given by named associations.
8737 ---------------------------
8738 -- Set_Discriminant_Name --
8739 ---------------------------
8741 procedure Set_Discriminant_Name (Id : Node_Id) is
8745 Set_Original_Discriminant (Id, Empty);
8747 if Has_Discriminants (Typ) then
8748 Disc := First_Discriminant (Typ);
8749 while Present (Disc) loop
8750 if Chars (Disc) = Chars (Id)
8751 and then Present (Corresponding_Discriminant (Disc))
8753 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8755 Next_Discriminant (Disc);
8758 end Set_Discriminant_Name;
8760 -- Start of processing for Build_Underlying_Full_View
8763 if Nkind (N) = N_Full_Type_Declaration then
8764 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8766 elsif Nkind (N) = N_Subtype_Declaration then
8767 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8769 elsif Nkind (N) = N_Component_Declaration then
8772 (Constraint (Subtype_Indication (Component_Definition (N))));
8775 raise Program_Error;
8778 C := First (Constraints (Constr));
8779 while Present (C) loop
8780 if Nkind (C) = N_Discriminant_Association then
8781 Id := First (Selector_Names (C));
8782 while Present (Id) loop
8783 Set_Discriminant_Name (Id);
8792 Make_Subtype_Declaration (Loc,
8793 Defining_Identifier => Subt,
8794 Subtype_Indication =>
8795 Make_Subtype_Indication (Loc,
8796 Subtype_Mark => New_Reference_To (Par, Loc),
8797 Constraint => New_Copy_Tree (Constr)));
8799 -- If this is a component subtype for an outer itype, it is not
8800 -- a list member, so simply set the parent link for analysis: if
8801 -- the enclosing type does not need to be in a declarative list,
8802 -- neither do the components.
8804 if Is_List_Member (N)
8805 and then Nkind (N) /= N_Component_Declaration
8807 Insert_Before (N, Indic);
8809 Set_Parent (Indic, Parent (N));
8813 Set_Underlying_Full_View (Typ, Full_View (Subt));
8814 end Build_Underlying_Full_View;
8816 -------------------------------
8817 -- Check_Abstract_Overriding --
8818 -------------------------------
8820 procedure Check_Abstract_Overriding (T : Entity_Id) is
8821 Alias_Subp : Entity_Id;
8827 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8828 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8829 -- which has pragma Implemented already set. Check whether Subp's entity
8830 -- kind conforms to the implementation kind of the overridden routine.
8832 procedure Check_Pragma_Implemented
8834 Iface_Subp : Entity_Id);
8835 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8836 -- Iface_Subp and both entities have pragma Implemented already set on
8837 -- them. Check whether the two implementation kinds are conforming.
8839 procedure Inherit_Pragma_Implemented
8841 Iface_Subp : Entity_Id);
8842 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8843 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8844 -- Propagate the implementation kind of Iface_Subp to Subp.
8846 ------------------------------
8847 -- Check_Pragma_Implemented --
8848 ------------------------------
8850 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8851 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8852 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8853 Contr_Typ : Entity_Id;
8856 -- Subp must have an alias since it is a hidden entity used to link
8857 -- an interface subprogram to its overriding counterpart.
8859 pragma Assert (Present (Alias (Subp)));
8861 -- Extract the type of the controlling formal
8863 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8865 if Is_Concurrent_Record_Type (Contr_Typ) then
8866 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8869 -- An interface subprogram whose implementation kind is By_Entry must
8870 -- be implemented by an entry.
8872 if Impl_Kind = Name_By_Entry
8873 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8875 Error_Msg_Node_2 := Iface_Alias;
8877 ("type & must implement abstract subprogram & with an entry",
8878 Alias (Subp), Contr_Typ);
8880 elsif Impl_Kind = Name_By_Protected_Procedure then
8882 -- An interface subprogram whose implementation kind is By_
8883 -- Protected_Procedure cannot be implemented by a primitive
8884 -- procedure of a task type.
8886 if Ekind (Contr_Typ) /= E_Protected_Type then
8887 Error_Msg_Node_2 := Contr_Typ;
8889 ("interface subprogram & cannot be implemented by a " &
8890 "primitive procedure of task type &", Alias (Subp),
8893 -- An interface subprogram whose implementation kind is By_
8894 -- Protected_Procedure must be implemented by a procedure.
8896 elsif Is_Primitive_Wrapper (Alias (Subp))
8897 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8899 Error_Msg_Node_2 := Iface_Alias;
8901 ("type & must implement abstract subprogram & with a " &
8902 "procedure", Alias (Subp), Contr_Typ);
8905 end Check_Pragma_Implemented;
8907 ------------------------------
8908 -- Check_Pragma_Implemented --
8909 ------------------------------
8911 procedure Check_Pragma_Implemented
8913 Iface_Subp : Entity_Id)
8915 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8916 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8919 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8920 -- and overriding subprogram are different. In general this is an
8921 -- error except when the implementation kind of the overridden
8922 -- subprograms is By_Any.
8924 if Iface_Kind /= Subp_Kind
8925 and then Iface_Kind /= Name_By_Any
8927 if Iface_Kind = Name_By_Entry then
8929 ("incompatible implementation kind, overridden subprogram " &
8930 "is marked By_Entry", Subp);
8933 ("incompatible implementation kind, overridden subprogram " &
8934 "is marked By_Protected_Procedure", Subp);
8937 end Check_Pragma_Implemented;
8939 --------------------------------
8940 -- Inherit_Pragma_Implemented --
8941 --------------------------------
8943 procedure Inherit_Pragma_Implemented
8945 Iface_Subp : Entity_Id)
8947 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8948 Loc : constant Source_Ptr := Sloc (Subp);
8949 Impl_Prag : Node_Id;
8952 -- Since the implementation kind is stored as a representation item
8953 -- rather than a flag, create a pragma node.
8957 Chars => Name_Implemented,
8958 Pragma_Argument_Associations => New_List (
8959 Make_Pragma_Argument_Association (Loc,
8961 New_Reference_To (Subp, Loc)),
8963 Make_Pragma_Argument_Association (Loc,
8964 Expression => Make_Identifier (Loc, Iface_Kind))));
8966 -- The pragma doesn't need to be analyzed because it is internally
8967 -- build. It is safe to directly register it as a rep item since we
8968 -- are only interested in the characters of the implementation kind.
8970 Record_Rep_Item (Subp, Impl_Prag);
8971 end Inherit_Pragma_Implemented;
8973 -- Start of processing for Check_Abstract_Overriding
8976 Op_List := Primitive_Operations (T);
8978 -- Loop to check primitive operations
8980 Elmt := First_Elmt (Op_List);
8981 while Present (Elmt) loop
8982 Subp := Node (Elmt);
8983 Alias_Subp := Alias (Subp);
8985 -- Inherited subprograms are identified by the fact that they do not
8986 -- come from source, and the associated source location is the
8987 -- location of the first subtype of the derived type.
8989 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8990 -- subprograms that "require overriding".
8992 -- Special exception, do not complain about failure to override the
8993 -- stream routines _Input and _Output, as well as the primitive
8994 -- operations used in dispatching selects since we always provide
8995 -- automatic overridings for these subprograms.
8997 -- Also ignore this rule for convention CIL since .NET libraries
8998 -- do bizarre things with interfaces???
9000 -- The partial view of T may have been a private extension, for
9001 -- which inherited functions dispatching on result are abstract.
9002 -- If the full view is a null extension, there is no need for
9003 -- overriding in Ada2005, but wrappers need to be built for them
9004 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9006 if Is_Null_Extension (T)
9007 and then Has_Controlling_Result (Subp)
9008 and then Ada_Version >= Ada_2005
9009 and then Present (Alias_Subp)
9010 and then not Comes_From_Source (Subp)
9011 and then not Is_Abstract_Subprogram (Alias_Subp)
9012 and then not Is_Access_Type (Etype (Subp))
9016 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9017 -- processing because this check is done with the aliased
9020 elsif Present (Interface_Alias (Subp)) then
9023 elsif (Is_Abstract_Subprogram (Subp)
9024 or else Requires_Overriding (Subp)
9026 (Has_Controlling_Result (Subp)
9027 and then Present (Alias_Subp)
9028 and then not Comes_From_Source (Subp)
9029 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9030 and then not Is_TSS (Subp, TSS_Stream_Input)
9031 and then not Is_TSS (Subp, TSS_Stream_Output)
9032 and then not Is_Abstract_Type (T)
9033 and then Convention (T) /= Convention_CIL
9034 and then not Is_Predefined_Interface_Primitive (Subp)
9036 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9037 -- with abstract interface types because the check will be done
9038 -- with the aliased entity (otherwise we generate a duplicated
9041 and then not Present (Interface_Alias (Subp))
9043 if Present (Alias_Subp) then
9045 -- Only perform the check for a derived subprogram when the
9046 -- type has an explicit record extension. This avoids incorrect
9047 -- flagging of abstract subprograms for the case of a type
9048 -- without an extension that is derived from a formal type
9049 -- with a tagged actual (can occur within a private part).
9051 -- Ada 2005 (AI-391): In the case of an inherited function with
9052 -- a controlling result of the type, the rule does not apply if
9053 -- the type is a null extension (unless the parent function
9054 -- itself is abstract, in which case the function must still be
9055 -- be overridden). The expander will generate an overriding
9056 -- wrapper function calling the parent subprogram (see
9057 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9059 Type_Def := Type_Definition (Parent (T));
9061 if Nkind (Type_Def) = N_Derived_Type_Definition
9062 and then Present (Record_Extension_Part (Type_Def))
9064 (Ada_Version < Ada_2005
9065 or else not Is_Null_Extension (T)
9066 or else Ekind (Subp) = E_Procedure
9067 or else not Has_Controlling_Result (Subp)
9068 or else Is_Abstract_Subprogram (Alias_Subp)
9069 or else Requires_Overriding (Subp)
9070 or else Is_Access_Type (Etype (Subp)))
9072 -- Avoid reporting error in case of abstract predefined
9073 -- primitive inherited from interface type because the
9074 -- body of internally generated predefined primitives
9075 -- of tagged types are generated later by Freeze_Type
9077 if Is_Interface (Root_Type (T))
9078 and then Is_Abstract_Subprogram (Subp)
9079 and then Is_Predefined_Dispatching_Operation (Subp)
9080 and then not Comes_From_Source (Ultimate_Alias (Subp))
9086 ("type must be declared abstract or & overridden",
9089 -- Traverse the whole chain of aliased subprograms to
9090 -- complete the error notification. This is especially
9091 -- useful for traceability of the chain of entities when
9092 -- the subprogram corresponds with an interface
9093 -- subprogram (which may be defined in another package).
9095 if Present (Alias_Subp) then
9101 while Present (Alias (E)) loop
9102 Error_Msg_Sloc := Sloc (E);
9104 ("\& has been inherited #", T, Subp);
9108 Error_Msg_Sloc := Sloc (E);
9110 ("\& has been inherited from subprogram #",
9116 -- Ada 2005 (AI-345): Protected or task type implementing
9117 -- abstract interfaces.
9119 elsif Is_Concurrent_Record_Type (T)
9120 and then Present (Interfaces (T))
9122 -- The controlling formal of Subp must be of mode "out",
9123 -- "in out" or an access-to-variable to be overridden.
9125 -- Error message below needs rewording (remember comma
9126 -- in -gnatj mode) ???
9128 if Ekind (First_Formal (Subp)) = E_In_Parameter
9129 and then Ekind (Subp) /= E_Function
9131 if not Is_Predefined_Dispatching_Operation (Subp) then
9133 ("first formal of & must be of mode `OUT`, " &
9134 "`IN OUT` or access-to-variable", T, Subp);
9136 ("\to be overridden by protected procedure or " &
9137 "entry (RM 9.4(11.9/2))", T);
9140 -- Some other kind of overriding failure
9144 ("interface subprogram & must be overridden",
9147 -- Examine primitive operations of synchronized type,
9148 -- to find homonyms that have the wrong profile.
9155 First_Entity (Corresponding_Concurrent_Type (T));
9156 while Present (Prim) loop
9157 if Chars (Prim) = Chars (Subp) then
9159 ("profile is not type conformant with "
9160 & "prefixed view profile of "
9161 & "inherited operation&", Prim, Subp);
9171 Error_Msg_Node_2 := T;
9173 ("abstract subprogram& not allowed for type&", Subp);
9175 -- Also post unconditional warning on the type (unconditional
9176 -- so that if there are more than one of these cases, we get
9177 -- them all, and not just the first one).
9179 Error_Msg_Node_2 := Subp;
9180 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9184 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9187 -- Subp is an expander-generated procedure which maps an interface
9188 -- alias to a protected wrapper. The interface alias is flagged by
9189 -- pragma Implemented. Ensure that Subp is a procedure when the
9190 -- implementation kind is By_Protected_Procedure or an entry when
9193 if Ada_Version >= Ada_2012
9194 and then Is_Hidden (Subp)
9195 and then Present (Interface_Alias (Subp))
9196 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9198 Check_Pragma_Implemented (Subp);
9201 -- Subp is an interface primitive which overrides another interface
9202 -- primitive marked with pragma Implemented.
9204 if Ada_Version >= Ada_2012
9205 and then Present (Overridden_Operation (Subp))
9206 and then Has_Rep_Pragma
9207 (Overridden_Operation (Subp), Name_Implemented)
9209 -- If the overriding routine is also marked by Implemented, check
9210 -- that the two implementation kinds are conforming.
9212 if Has_Rep_Pragma (Subp, Name_Implemented) then
9213 Check_Pragma_Implemented
9215 Iface_Subp => Overridden_Operation (Subp));
9217 -- Otherwise the overriding routine inherits the implementation
9218 -- kind from the overridden subprogram.
9221 Inherit_Pragma_Implemented
9223 Iface_Subp => Overridden_Operation (Subp));
9229 end Check_Abstract_Overriding;
9231 ------------------------------------------------
9232 -- Check_Access_Discriminant_Requires_Limited --
9233 ------------------------------------------------
9235 procedure Check_Access_Discriminant_Requires_Limited
9240 -- A discriminant_specification for an access discriminant shall appear
9241 -- only in the declaration for a task or protected type, or for a type
9242 -- with the reserved word 'limited' in its definition or in one of its
9243 -- ancestors (RM 3.7(10)).
9245 -- AI-0063: The proper condition is that type must be immutably limited,
9246 -- or else be a partial view.
9248 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9249 if Is_Immutably_Limited_Type (Current_Scope)
9251 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9252 and then Limited_Present (Parent (Current_Scope)))
9258 ("access discriminants allowed only for limited types", Loc);
9261 end Check_Access_Discriminant_Requires_Limited;
9263 -----------------------------------
9264 -- Check_Aliased_Component_Types --
9265 -----------------------------------
9267 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9271 -- ??? Also need to check components of record extensions, but not
9272 -- components of protected types (which are always limited).
9274 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9275 -- types to be unconstrained. This is safe because it is illegal to
9276 -- create access subtypes to such types with explicit discriminant
9279 if not Is_Limited_Type (T) then
9280 if Ekind (T) = E_Record_Type then
9281 C := First_Component (T);
9282 while Present (C) loop
9284 and then Has_Discriminants (Etype (C))
9285 and then not Is_Constrained (Etype (C))
9286 and then not In_Instance_Body
9287 and then Ada_Version < Ada_2005
9290 ("aliased component must be constrained (RM 3.6(11))",
9297 elsif Ekind (T) = E_Array_Type then
9298 if Has_Aliased_Components (T)
9299 and then Has_Discriminants (Component_Type (T))
9300 and then not Is_Constrained (Component_Type (T))
9301 and then not In_Instance_Body
9302 and then Ada_Version < Ada_2005
9305 ("aliased component type must be constrained (RM 3.6(11))",
9310 end Check_Aliased_Component_Types;
9312 ----------------------
9313 -- Check_Completion --
9314 ----------------------
9316 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9319 procedure Post_Error;
9320 -- Post error message for lack of completion for entity E
9326 procedure Post_Error is
9328 procedure Missing_Body;
9329 -- Output missing body message
9335 procedure Missing_Body is
9337 -- Spec is in same unit, so we can post on spec
9339 if In_Same_Source_Unit (Body_Id, E) then
9340 Error_Msg_N ("missing body for &", E);
9342 -- Spec is in a separate unit, so we have to post on the body
9345 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9349 -- Start of processing for Post_Error
9352 if not Comes_From_Source (E) then
9354 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9355 -- It may be an anonymous protected type created for a
9356 -- single variable. Post error on variable, if present.
9362 Var := First_Entity (Current_Scope);
9363 while Present (Var) loop
9364 exit when Etype (Var) = E
9365 and then Comes_From_Source (Var);
9370 if Present (Var) then
9377 -- If a generated entity has no completion, then either previous
9378 -- semantic errors have disabled the expansion phase, or else we had
9379 -- missing subunits, or else we are compiling without expansion,
9380 -- or else something is very wrong.
9382 if not Comes_From_Source (E) then
9384 (Serious_Errors_Detected > 0
9385 or else Configurable_Run_Time_Violations > 0
9386 or else Subunits_Missing
9387 or else not Expander_Active);
9390 -- Here for source entity
9393 -- Here if no body to post the error message, so we post the error
9394 -- on the declaration that has no completion. This is not really
9395 -- the right place to post it, think about this later ???
9397 if No (Body_Id) then
9400 ("missing full declaration for }", Parent (E), E);
9402 Error_Msg_NE ("missing body for &", Parent (E), E);
9405 -- Package body has no completion for a declaration that appears
9406 -- in the corresponding spec. Post error on the body, with a
9407 -- reference to the non-completed declaration.
9410 Error_Msg_Sloc := Sloc (E);
9413 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9415 elsif Is_Overloadable (E)
9416 and then Current_Entity_In_Scope (E) /= E
9418 -- It may be that the completion is mistyped and appears as
9419 -- a distinct overloading of the entity.
9422 Candidate : constant Entity_Id :=
9423 Current_Entity_In_Scope (E);
9424 Decl : constant Node_Id :=
9425 Unit_Declaration_Node (Candidate);
9428 if Is_Overloadable (Candidate)
9429 and then Ekind (Candidate) = Ekind (E)
9430 and then Nkind (Decl) = N_Subprogram_Body
9431 and then Acts_As_Spec (Decl)
9433 Check_Type_Conformant (Candidate, E);
9447 -- Start of processing for Check_Completion
9450 E := First_Entity (Current_Scope);
9451 while Present (E) loop
9452 if Is_Intrinsic_Subprogram (E) then
9455 -- The following situation requires special handling: a child unit
9456 -- that appears in the context clause of the body of its parent:
9458 -- procedure Parent.Child (...);
9460 -- with Parent.Child;
9461 -- package body Parent is
9463 -- Here Parent.Child appears as a local entity, but should not be
9464 -- flagged as requiring completion, because it is a compilation
9467 -- Ignore missing completion for a subprogram that does not come from
9468 -- source (including the _Call primitive operation of RAS types,
9469 -- which has to have the flag Comes_From_Source for other purposes):
9470 -- we assume that the expander will provide the missing completion.
9471 -- In case of previous errors, other expansion actions that provide
9472 -- bodies for null procedures with not be invoked, so inhibit message
9474 -- Note that E_Operator is not in the list that follows, because
9475 -- this kind is reserved for predefined operators, that are
9476 -- intrinsic and do not need completion.
9478 elsif Ekind (E) = E_Function
9479 or else Ekind (E) = E_Procedure
9480 or else Ekind (E) = E_Generic_Function
9481 or else Ekind (E) = E_Generic_Procedure
9483 if Has_Completion (E) then
9486 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9489 elsif Is_Subprogram (E)
9490 and then (not Comes_From_Source (E)
9491 or else Chars (E) = Name_uCall)
9496 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9500 elsif Nkind (Parent (E)) = N_Procedure_Specification
9501 and then Null_Present (Parent (E))
9502 and then Serious_Errors_Detected > 0
9510 elsif Is_Entry (E) then
9511 if not Has_Completion (E) and then
9512 (Ekind (Scope (E)) = E_Protected_Object
9513 or else Ekind (Scope (E)) = E_Protected_Type)
9518 elsif Is_Package_Or_Generic_Package (E) then
9519 if Unit_Requires_Body (E) then
9520 if not Has_Completion (E)
9521 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9527 elsif not Is_Child_Unit (E) then
9528 May_Need_Implicit_Body (E);
9531 elsif Ekind (E) = E_Incomplete_Type
9532 and then No (Underlying_Type (E))
9536 elsif (Ekind (E) = E_Task_Type or else
9537 Ekind (E) = E_Protected_Type)
9538 and then not Has_Completion (E)
9542 -- A single task declared in the current scope is a constant, verify
9543 -- that the body of its anonymous type is in the same scope. If the
9544 -- task is defined elsewhere, this may be a renaming declaration for
9545 -- which no completion is needed.
9547 elsif Ekind (E) = E_Constant
9548 and then Ekind (Etype (E)) = E_Task_Type
9549 and then not Has_Completion (Etype (E))
9550 and then Scope (Etype (E)) = Current_Scope
9554 elsif Ekind (E) = E_Protected_Object
9555 and then not Has_Completion (Etype (E))
9559 elsif Ekind (E) = E_Record_Type then
9560 if Is_Tagged_Type (E) then
9561 Check_Abstract_Overriding (E);
9562 Check_Conventions (E);
9565 Check_Aliased_Component_Types (E);
9567 elsif Ekind (E) = E_Array_Type then
9568 Check_Aliased_Component_Types (E);
9574 end Check_Completion;
9576 ----------------------------
9577 -- Check_Delta_Expression --
9578 ----------------------------
9580 procedure Check_Delta_Expression (E : Node_Id) is
9582 if not (Is_Real_Type (Etype (E))) then
9583 Wrong_Type (E, Any_Real);
9585 elsif not Is_OK_Static_Expression (E) then
9586 Flag_Non_Static_Expr
9587 ("non-static expression used for delta value!", E);
9589 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9590 Error_Msg_N ("delta expression must be positive", E);
9596 -- If any of above errors occurred, then replace the incorrect
9597 -- expression by the real 0.1, which should prevent further errors.
9600 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9601 Analyze_And_Resolve (E, Standard_Float);
9602 end Check_Delta_Expression;
9604 -----------------------------
9605 -- Check_Digits_Expression --
9606 -----------------------------
9608 procedure Check_Digits_Expression (E : Node_Id) is
9610 if not (Is_Integer_Type (Etype (E))) then
9611 Wrong_Type (E, Any_Integer);
9613 elsif not Is_OK_Static_Expression (E) then
9614 Flag_Non_Static_Expr
9615 ("non-static expression used for digits value!", E);
9617 elsif Expr_Value (E) <= 0 then
9618 Error_Msg_N ("digits value must be greater than zero", E);
9624 -- If any of above errors occurred, then replace the incorrect
9625 -- expression by the integer 1, which should prevent further errors.
9627 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9628 Analyze_And_Resolve (E, Standard_Integer);
9630 end Check_Digits_Expression;
9632 --------------------------
9633 -- Check_Initialization --
9634 --------------------------
9636 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9638 if Is_Limited_Type (T)
9639 and then not In_Instance
9640 and then not In_Inlined_Body
9642 if not OK_For_Limited_Init (T, Exp) then
9644 -- In GNAT mode, this is just a warning, to allow it to be evilly
9645 -- turned off. Otherwise it is a real error.
9649 ("?cannot initialize entities of limited type!", Exp);
9651 elsif Ada_Version < Ada_2005 then
9653 ("cannot initialize entities of limited type", Exp);
9654 Explain_Limited_Type (T, Exp);
9657 -- Specialize error message according to kind of illegal
9658 -- initial expression.
9660 if Nkind (Exp) = N_Type_Conversion
9661 and then Nkind (Expression (Exp)) = N_Function_Call
9664 ("illegal context for call"
9665 & " to function with limited result", Exp);
9669 ("initialization of limited object requires aggregate "
9670 & "or function call", Exp);
9675 end Check_Initialization;
9677 ----------------------
9678 -- Check_Interfaces --
9679 ----------------------
9681 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9682 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9685 Iface_Def : Node_Id;
9686 Iface_Typ : Entity_Id;
9687 Parent_Node : Node_Id;
9689 Is_Task : Boolean := False;
9690 -- Set True if parent type or any progenitor is a task interface
9692 Is_Protected : Boolean := False;
9693 -- Set True if parent type or any progenitor is a protected interface
9695 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9696 -- Check that a progenitor is compatible with declaration.
9697 -- Error is posted on Error_Node.
9703 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9704 Iface_Id : constant Entity_Id :=
9705 Defining_Identifier (Parent (Iface_Def));
9709 if Nkind (N) = N_Private_Extension_Declaration then
9712 Type_Def := Type_Definition (N);
9715 if Is_Task_Interface (Iface_Id) then
9718 elsif Is_Protected_Interface (Iface_Id) then
9719 Is_Protected := True;
9722 if Is_Synchronized_Interface (Iface_Id) then
9724 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9725 -- extension derived from a synchronized interface must explicitly
9726 -- be declared synchronized, because the full view will be a
9727 -- synchronized type.
9729 if Nkind (N) = N_Private_Extension_Declaration then
9730 if not Synchronized_Present (N) then
9732 ("private extension of& must be explicitly synchronized",
9736 -- However, by 3.9.4(16/2), a full type that is a record extension
9737 -- is never allowed to derive from a synchronized interface (note
9738 -- that interfaces must be excluded from this check, because those
9739 -- are represented by derived type definitions in some cases).
9741 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9742 and then not Interface_Present (Type_Definition (N))
9744 Error_Msg_N ("record extension cannot derive from synchronized"
9745 & " interface", Error_Node);
9749 -- Check that the characteristics of the progenitor are compatible
9750 -- with the explicit qualifier in the declaration.
9751 -- The check only applies to qualifiers that come from source.
9752 -- Limited_Present also appears in the declaration of corresponding
9753 -- records, and the check does not apply to them.
9755 if Limited_Present (Type_Def)
9757 Is_Concurrent_Record_Type (Defining_Identifier (N))
9759 if Is_Limited_Interface (Parent_Type)
9760 and then not Is_Limited_Interface (Iface_Id)
9763 ("progenitor& must be limited interface",
9764 Error_Node, Iface_Id);
9767 (Task_Present (Iface_Def)
9768 or else Protected_Present (Iface_Def)
9769 or else Synchronized_Present (Iface_Def))
9770 and then Nkind (N) /= N_Private_Extension_Declaration
9771 and then not Error_Posted (N)
9774 ("progenitor& must be limited interface",
9775 Error_Node, Iface_Id);
9778 -- Protected interfaces can only inherit from limited, synchronized
9779 -- or protected interfaces.
9781 elsif Nkind (N) = N_Full_Type_Declaration
9782 and then Protected_Present (Type_Def)
9784 if Limited_Present (Iface_Def)
9785 or else Synchronized_Present (Iface_Def)
9786 or else Protected_Present (Iface_Def)
9790 elsif Task_Present (Iface_Def) then
9791 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9792 & " from task interface", Error_Node);
9795 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9796 & " from non-limited interface", Error_Node);
9799 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9800 -- limited and synchronized.
9802 elsif Synchronized_Present (Type_Def) then
9803 if Limited_Present (Iface_Def)
9804 or else Synchronized_Present (Iface_Def)
9808 elsif Protected_Present (Iface_Def)
9809 and then Nkind (N) /= N_Private_Extension_Declaration
9811 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9812 & " from protected interface", Error_Node);
9814 elsif Task_Present (Iface_Def)
9815 and then Nkind (N) /= N_Private_Extension_Declaration
9817 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9818 & " from task interface", Error_Node);
9820 elsif not Is_Limited_Interface (Iface_Id) then
9821 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9822 & " from non-limited interface", Error_Node);
9825 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9826 -- synchronized or task interfaces.
9828 elsif Nkind (N) = N_Full_Type_Declaration
9829 and then Task_Present (Type_Def)
9831 if Limited_Present (Iface_Def)
9832 or else Synchronized_Present (Iface_Def)
9833 or else Task_Present (Iface_Def)
9837 elsif Protected_Present (Iface_Def) then
9838 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9839 & " protected interface", Error_Node);
9842 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9843 & " non-limited interface", Error_Node);
9848 -- Start of processing for Check_Interfaces
9851 if Is_Interface (Parent_Type) then
9852 if Is_Task_Interface (Parent_Type) then
9855 elsif Is_Protected_Interface (Parent_Type) then
9856 Is_Protected := True;
9860 if Nkind (N) = N_Private_Extension_Declaration then
9862 -- Check that progenitors are compatible with declaration
9864 Iface := First (Interface_List (Def));
9865 while Present (Iface) loop
9866 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9868 Parent_Node := Parent (Base_Type (Iface_Typ));
9869 Iface_Def := Type_Definition (Parent_Node);
9871 if not Is_Interface (Iface_Typ) then
9872 Diagnose_Interface (Iface, Iface_Typ);
9875 Check_Ifaces (Iface_Def, Iface);
9881 if Is_Task and Is_Protected then
9883 ("type cannot derive from task and protected interface", N);
9889 -- Full type declaration of derived type.
9890 -- Check compatibility with parent if it is interface type
9892 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9893 and then Is_Interface (Parent_Type)
9895 Parent_Node := Parent (Parent_Type);
9897 -- More detailed checks for interface varieties
9900 (Iface_Def => Type_Definition (Parent_Node),
9901 Error_Node => Subtype_Indication (Type_Definition (N)));
9904 Iface := First (Interface_List (Def));
9905 while Present (Iface) loop
9906 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9908 Parent_Node := Parent (Base_Type (Iface_Typ));
9909 Iface_Def := Type_Definition (Parent_Node);
9911 if not Is_Interface (Iface_Typ) then
9912 Diagnose_Interface (Iface, Iface_Typ);
9915 -- "The declaration of a specific descendant of an interface
9916 -- type freezes the interface type" RM 13.14
9918 Freeze_Before (N, Iface_Typ);
9919 Check_Ifaces (Iface_Def, Error_Node => Iface);
9925 if Is_Task and Is_Protected then
9927 ("type cannot derive from task and protected interface", N);
9929 end Check_Interfaces;
9931 ------------------------------------
9932 -- Check_Or_Process_Discriminants --
9933 ------------------------------------
9935 -- If an incomplete or private type declaration was already given for the
9936 -- type, the discriminants may have already been processed if they were
9937 -- present on the incomplete declaration. In this case a full conformance
9938 -- check has been performed in Find_Type_Name, and we then recheck here
9939 -- some properties that can't be checked on the partial view alone.
9940 -- Otherwise we call Process_Discriminants.
9942 procedure Check_Or_Process_Discriminants
9945 Prev : Entity_Id := Empty)
9948 if Has_Discriminants (T) then
9950 -- Discriminants are already set on T if they were already present
9951 -- on the partial view. Make them visible to component declarations.
9955 -- Discriminant on T (full view) referencing expr on partial view
9958 -- Entity of corresponding discriminant on partial view
9961 -- Discriminant specification for full view, expression is the
9962 -- syntactic copy on full view (which has been checked for
9963 -- conformance with partial view), only used here to post error
9967 D := First_Discriminant (T);
9968 New_D := First (Discriminant_Specifications (N));
9969 while Present (D) loop
9970 Prev_D := Current_Entity (D);
9971 Set_Current_Entity (D);
9972 Set_Is_Immediately_Visible (D);
9973 Set_Homonym (D, Prev_D);
9975 -- Handle the case where there is an untagged partial view and
9976 -- the full view is tagged: must disallow discriminants with
9977 -- defaults, unless compiling for Ada 2012, which allows a
9978 -- limited tagged type to have defaulted discriminants (see
9979 -- AI05-0214). However, suppress the error here if it was
9980 -- already reported on the default expression of the partial
9983 if Is_Tagged_Type (T)
9984 and then Present (Expression (Parent (D)))
9985 and then (not Is_Limited_Type (Current_Scope)
9986 or else Ada_Version < Ada_2012)
9987 and then not Error_Posted (Expression (Parent (D)))
9989 if Ada_Version >= Ada_2012 then
9991 ("discriminants of nonlimited tagged type cannot have"
9993 Expression (New_D));
9996 ("discriminants of tagged type cannot have defaults",
9997 Expression (New_D));
10001 -- Ada 2005 (AI-230): Access discriminant allowed in
10002 -- non-limited record types.
10004 if Ada_Version < Ada_2005 then
10006 -- This restriction gets applied to the full type here. It
10007 -- has already been applied earlier to the partial view.
10009 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10012 Next_Discriminant (D);
10017 elsif Present (Discriminant_Specifications (N)) then
10018 Process_Discriminants (N, Prev);
10020 end Check_Or_Process_Discriminants;
10022 ----------------------
10023 -- Check_Real_Bound --
10024 ----------------------
10026 procedure Check_Real_Bound (Bound : Node_Id) is
10028 if not Is_Real_Type (Etype (Bound)) then
10030 ("bound in real type definition must be of real type", Bound);
10032 elsif not Is_OK_Static_Expression (Bound) then
10033 Flag_Non_Static_Expr
10034 ("non-static expression used for real type bound!", Bound);
10041 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10043 Resolve (Bound, Standard_Float);
10044 end Check_Real_Bound;
10046 ------------------------------
10047 -- Complete_Private_Subtype --
10048 ------------------------------
10050 procedure Complete_Private_Subtype
10053 Full_Base : Entity_Id;
10054 Related_Nod : Node_Id)
10056 Save_Next_Entity : Entity_Id;
10057 Save_Homonym : Entity_Id;
10060 -- Set semantic attributes for (implicit) private subtype completion.
10061 -- If the full type has no discriminants, then it is a copy of the full
10062 -- view of the base. Otherwise, it is a subtype of the base with a
10063 -- possible discriminant constraint. Save and restore the original
10064 -- Next_Entity field of full to ensure that the calls to Copy_Node
10065 -- do not corrupt the entity chain.
10067 -- Note that the type of the full view is the same entity as the type of
10068 -- the partial view. In this fashion, the subtype has access to the
10069 -- correct view of the parent.
10071 Save_Next_Entity := Next_Entity (Full);
10072 Save_Homonym := Homonym (Priv);
10074 case Ekind (Full_Base) is
10075 when E_Record_Type |
10081 Copy_Node (Priv, Full);
10083 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10084 Set_First_Entity (Full, First_Entity (Full_Base));
10085 Set_Last_Entity (Full, Last_Entity (Full_Base));
10088 Copy_Node (Full_Base, Full);
10089 Set_Chars (Full, Chars (Priv));
10090 Conditional_Delay (Full, Priv);
10091 Set_Sloc (Full, Sloc (Priv));
10094 Set_Next_Entity (Full, Save_Next_Entity);
10095 Set_Homonym (Full, Save_Homonym);
10096 Set_Associated_Node_For_Itype (Full, Related_Nod);
10098 -- Set common attributes for all subtypes: kind, convention, etc.
10100 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10101 Set_Convention (Full, Convention (Full_Base));
10103 -- The Etype of the full view is inconsistent. Gigi needs to see the
10104 -- structural full view, which is what the current scheme gives:
10105 -- the Etype of the full view is the etype of the full base. However,
10106 -- if the full base is a derived type, the full view then looks like
10107 -- a subtype of the parent, not a subtype of the full base. If instead
10110 -- Set_Etype (Full, Full_Base);
10112 -- then we get inconsistencies in the front-end (confusion between
10113 -- views). Several outstanding bugs are related to this ???
10115 Set_Is_First_Subtype (Full, False);
10116 Set_Scope (Full, Scope (Priv));
10117 Set_Size_Info (Full, Full_Base);
10118 Set_RM_Size (Full, RM_Size (Full_Base));
10119 Set_Is_Itype (Full);
10121 -- A subtype of a private-type-without-discriminants, whose full-view
10122 -- has discriminants with default expressions, is not constrained!
10124 if not Has_Discriminants (Priv) then
10125 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10127 if Has_Discriminants (Full_Base) then
10128 Set_Discriminant_Constraint
10129 (Full, Discriminant_Constraint (Full_Base));
10131 -- The partial view may have been indefinite, the full view
10134 Set_Has_Unknown_Discriminants
10135 (Full, Has_Unknown_Discriminants (Full_Base));
10139 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10140 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10142 -- Freeze the private subtype entity if its parent is delayed, and not
10143 -- already frozen. We skip this processing if the type is an anonymous
10144 -- subtype of a record component, or is the corresponding record of a
10145 -- protected type, since ???
10147 if not Is_Type (Scope (Full)) then
10148 Set_Has_Delayed_Freeze (Full,
10149 Has_Delayed_Freeze (Full_Base)
10150 and then (not Is_Frozen (Full_Base)));
10153 Set_Freeze_Node (Full, Empty);
10154 Set_Is_Frozen (Full, False);
10155 Set_Full_View (Priv, Full);
10157 if Has_Discriminants (Full) then
10158 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10159 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10161 if Has_Unknown_Discriminants (Full) then
10162 Set_Discriminant_Constraint (Full, No_Elist);
10166 if Ekind (Full_Base) = E_Record_Type
10167 and then Has_Discriminants (Full_Base)
10168 and then Has_Discriminants (Priv) -- might not, if errors
10169 and then not Has_Unknown_Discriminants (Priv)
10170 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10172 Create_Constrained_Components
10173 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10175 -- If the full base is itself derived from private, build a congruent
10176 -- subtype of its underlying type, for use by the back end. For a
10177 -- constrained record component, the declaration cannot be placed on
10178 -- the component list, but it must nevertheless be built an analyzed, to
10179 -- supply enough information for Gigi to compute the size of component.
10181 elsif Ekind (Full_Base) in Private_Kind
10182 and then Is_Derived_Type (Full_Base)
10183 and then Has_Discriminants (Full_Base)
10184 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10186 if not Is_Itype (Priv)
10188 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10190 Build_Underlying_Full_View
10191 (Parent (Priv), Full, Etype (Full_Base));
10193 elsif Nkind (Related_Nod) = N_Component_Declaration then
10194 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10197 elsif Is_Record_Type (Full_Base) then
10199 -- Show Full is simply a renaming of Full_Base
10201 Set_Cloned_Subtype (Full, Full_Base);
10204 -- It is unsafe to share to bounds of a scalar type, because the Itype
10205 -- is elaborated on demand, and if a bound is non-static then different
10206 -- orders of elaboration in different units will lead to different
10207 -- external symbols.
10209 if Is_Scalar_Type (Full_Base) then
10210 Set_Scalar_Range (Full,
10211 Make_Range (Sloc (Related_Nod),
10213 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10215 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10217 -- This completion inherits the bounds of the full parent, but if
10218 -- the parent is an unconstrained floating point type, so is the
10221 if Is_Floating_Point_Type (Full_Base) then
10222 Set_Includes_Infinities
10223 (Scalar_Range (Full), Has_Infinities (Full_Base));
10227 -- ??? It seems that a lot of fields are missing that should be copied
10228 -- from Full_Base to Full. Here are some that are introduced in a
10229 -- non-disruptive way but a cleanup is necessary.
10231 if Is_Tagged_Type (Full_Base) then
10232 Set_Is_Tagged_Type (Full);
10233 Set_Direct_Primitive_Operations (Full,
10234 Direct_Primitive_Operations (Full_Base));
10236 -- Inherit class_wide type of full_base in case the partial view was
10237 -- not tagged. Otherwise it has already been created when the private
10238 -- subtype was analyzed.
10240 if No (Class_Wide_Type (Full)) then
10241 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10244 -- If this is a subtype of a protected or task type, constrain its
10245 -- corresponding record, unless this is a subtype without constraints,
10246 -- i.e. a simple renaming as with an actual subtype in an instance.
10248 elsif Is_Concurrent_Type (Full_Base) then
10249 if Has_Discriminants (Full)
10250 and then Present (Corresponding_Record_Type (Full_Base))
10252 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10254 Set_Corresponding_Record_Type (Full,
10255 Constrain_Corresponding_Record
10256 (Full, Corresponding_Record_Type (Full_Base),
10257 Related_Nod, Full_Base));
10260 Set_Corresponding_Record_Type (Full,
10261 Corresponding_Record_Type (Full_Base));
10265 -- Link rep item chain, and also setting of Has_Predicates from private
10266 -- subtype to full subtype, since we will need these on the full subtype
10267 -- to create the predicate function. Note that the full subtype may
10268 -- already have rep items, inherited from the full view of the base
10269 -- type, so we must be sure not to overwrite these entries.
10273 Next_Item : Node_Id;
10276 Item := First_Rep_Item (Full);
10278 -- If no existing rep items on full type, we can just link directly
10279 -- to the list of items on the private type.
10282 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10284 -- Otherwise, search to the end of items currently linked to the full
10285 -- subtype and append the private items to the end. However, if Priv
10286 -- and Full already have the same list of rep items, then the append
10287 -- is not done, as that would create a circularity.
10289 elsif Item /= First_Rep_Item (Priv) then
10291 Next_Item := Next_Rep_Item (Item);
10292 exit when No (Next_Item);
10296 -- And link the private type items at the end of the chain
10298 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10302 -- Make sure Has_Predicates is set on full type if it is set on the
10303 -- private type. Note that it may already be set on the full type and
10304 -- if so, we don't want to unset it.
10306 if Has_Predicates (Priv) then
10307 Set_Has_Predicates (Full);
10309 end Complete_Private_Subtype;
10311 ----------------------------
10312 -- Constant_Redeclaration --
10313 ----------------------------
10315 procedure Constant_Redeclaration
10320 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10321 Obj_Def : constant Node_Id := Object_Definition (N);
10324 procedure Check_Possible_Deferred_Completion
10325 (Prev_Id : Entity_Id;
10326 Prev_Obj_Def : Node_Id;
10327 Curr_Obj_Def : Node_Id);
10328 -- Determine whether the two object definitions describe the partial
10329 -- and the full view of a constrained deferred constant. Generate
10330 -- a subtype for the full view and verify that it statically matches
10331 -- the subtype of the partial view.
10333 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10334 -- If deferred constant is an access type initialized with an allocator,
10335 -- check whether there is an illegal recursion in the definition,
10336 -- through a default value of some record subcomponent. This is normally
10337 -- detected when generating init procs, but requires this additional
10338 -- mechanism when expansion is disabled.
10340 ----------------------------------------
10341 -- Check_Possible_Deferred_Completion --
10342 ----------------------------------------
10344 procedure Check_Possible_Deferred_Completion
10345 (Prev_Id : Entity_Id;
10346 Prev_Obj_Def : Node_Id;
10347 Curr_Obj_Def : Node_Id)
10350 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10351 and then Present (Constraint (Prev_Obj_Def))
10352 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10353 and then Present (Constraint (Curr_Obj_Def))
10356 Loc : constant Source_Ptr := Sloc (N);
10357 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10358 Decl : constant Node_Id :=
10359 Make_Subtype_Declaration (Loc,
10360 Defining_Identifier => Def_Id,
10361 Subtype_Indication =>
10362 Relocate_Node (Curr_Obj_Def));
10365 Insert_Before_And_Analyze (N, Decl);
10366 Set_Etype (Id, Def_Id);
10368 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10369 Error_Msg_Sloc := Sloc (Prev_Id);
10370 Error_Msg_N ("subtype does not statically match deferred " &
10371 "declaration#", N);
10375 end Check_Possible_Deferred_Completion;
10377 ---------------------------------
10378 -- Check_Recursive_Declaration --
10379 ---------------------------------
10381 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10385 if Is_Record_Type (Typ) then
10386 Comp := First_Component (Typ);
10387 while Present (Comp) loop
10388 if Comes_From_Source (Comp) then
10389 if Present (Expression (Parent (Comp)))
10390 and then Is_Entity_Name (Expression (Parent (Comp)))
10391 and then Entity (Expression (Parent (Comp))) = Prev
10393 Error_Msg_Sloc := Sloc (Parent (Comp));
10395 ("illegal circularity with declaration for&#",
10399 elsif Is_Record_Type (Etype (Comp)) then
10400 Check_Recursive_Declaration (Etype (Comp));
10404 Next_Component (Comp);
10407 end Check_Recursive_Declaration;
10409 -- Start of processing for Constant_Redeclaration
10412 if Nkind (Parent (Prev)) = N_Object_Declaration then
10413 if Nkind (Object_Definition
10414 (Parent (Prev))) = N_Subtype_Indication
10416 -- Find type of new declaration. The constraints of the two
10417 -- views must match statically, but there is no point in
10418 -- creating an itype for the full view.
10420 if Nkind (Obj_Def) = N_Subtype_Indication then
10421 Find_Type (Subtype_Mark (Obj_Def));
10422 New_T := Entity (Subtype_Mark (Obj_Def));
10425 Find_Type (Obj_Def);
10426 New_T := Entity (Obj_Def);
10432 -- The full view may impose a constraint, even if the partial
10433 -- view does not, so construct the subtype.
10435 New_T := Find_Type_Of_Object (Obj_Def, N);
10440 -- Current declaration is illegal, diagnosed below in Enter_Name
10446 -- If previous full declaration or a renaming declaration exists, or if
10447 -- a homograph is present, let Enter_Name handle it, either with an
10448 -- error or with the removal of an overridden implicit subprogram.
10450 if Ekind (Prev) /= E_Constant
10451 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10452 or else Present (Expression (Parent (Prev)))
10453 or else Present (Full_View (Prev))
10457 -- Verify that types of both declarations match, or else that both types
10458 -- are anonymous access types whose designated subtypes statically match
10459 -- (as allowed in Ada 2005 by AI-385).
10461 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10463 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10464 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10465 or else Is_Access_Constant (Etype (New_T)) /=
10466 Is_Access_Constant (Etype (Prev))
10467 or else Can_Never_Be_Null (Etype (New_T)) /=
10468 Can_Never_Be_Null (Etype (Prev))
10469 or else Null_Exclusion_Present (Parent (Prev)) /=
10470 Null_Exclusion_Present (Parent (Id))
10471 or else not Subtypes_Statically_Match
10472 (Designated_Type (Etype (Prev)),
10473 Designated_Type (Etype (New_T))))
10475 Error_Msg_Sloc := Sloc (Prev);
10476 Error_Msg_N ("type does not match declaration#", N);
10477 Set_Full_View (Prev, Id);
10478 Set_Etype (Id, Any_Type);
10481 Null_Exclusion_Present (Parent (Prev))
10482 and then not Null_Exclusion_Present (N)
10484 Error_Msg_Sloc := Sloc (Prev);
10485 Error_Msg_N ("null-exclusion does not match declaration#", N);
10486 Set_Full_View (Prev, Id);
10487 Set_Etype (Id, Any_Type);
10489 -- If so, process the full constant declaration
10492 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10493 -- the deferred declaration is constrained, then the subtype defined
10494 -- by the subtype_indication in the full declaration shall match it
10497 Check_Possible_Deferred_Completion
10499 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10500 Curr_Obj_Def => Obj_Def);
10502 Set_Full_View (Prev, Id);
10503 Set_Is_Public (Id, Is_Public (Prev));
10504 Set_Is_Internal (Id);
10505 Append_Entity (Id, Current_Scope);
10507 -- Check ALIASED present if present before (RM 7.4(7))
10509 if Is_Aliased (Prev)
10510 and then not Aliased_Present (N)
10512 Error_Msg_Sloc := Sloc (Prev);
10513 Error_Msg_N ("ALIASED required (see declaration#)", N);
10516 -- Check that placement is in private part and that the incomplete
10517 -- declaration appeared in the visible part.
10519 if Ekind (Current_Scope) = E_Package
10520 and then not In_Private_Part (Current_Scope)
10522 Error_Msg_Sloc := Sloc (Prev);
10524 ("full constant for declaration#"
10525 & " must be in private part", N);
10527 elsif Ekind (Current_Scope) = E_Package
10529 List_Containing (Parent (Prev)) /=
10530 Visible_Declarations
10531 (Specification (Unit_Declaration_Node (Current_Scope)))
10534 ("deferred constant must be declared in visible part",
10538 if Is_Access_Type (T)
10539 and then Nkind (Expression (N)) = N_Allocator
10541 Check_Recursive_Declaration (Designated_Type (T));
10544 end Constant_Redeclaration;
10546 ----------------------
10547 -- Constrain_Access --
10548 ----------------------
10550 procedure Constrain_Access
10551 (Def_Id : in out Entity_Id;
10553 Related_Nod : Node_Id)
10555 T : constant Entity_Id := Entity (Subtype_Mark (S));
10556 Desig_Type : constant Entity_Id := Designated_Type (T);
10557 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10558 Constraint_OK : Boolean := True;
10560 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10561 -- Simple predicate to test for defaulted discriminants
10562 -- Shouldn't this be in sem_util???
10564 ---------------------------------
10565 -- Has_Defaulted_Discriminants --
10566 ---------------------------------
10568 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10570 return Has_Discriminants (Typ)
10571 and then Present (First_Discriminant (Typ))
10573 (Discriminant_Default_Value (First_Discriminant (Typ)));
10574 end Has_Defaulted_Discriminants;
10576 -- Start of processing for Constrain_Access
10579 if Is_Array_Type (Desig_Type) then
10580 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10582 elsif (Is_Record_Type (Desig_Type)
10583 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10584 and then not Is_Constrained (Desig_Type)
10586 -- ??? The following code is a temporary kludge to ignore a
10587 -- discriminant constraint on access type if it is constraining
10588 -- the current record. Avoid creating the implicit subtype of the
10589 -- record we are currently compiling since right now, we cannot
10590 -- handle these. For now, just return the access type itself.
10592 if Desig_Type = Current_Scope
10593 and then No (Def_Id)
10595 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10596 Def_Id := Entity (Subtype_Mark (S));
10598 -- This call added to ensure that the constraint is analyzed
10599 -- (needed for a B test). Note that we still return early from
10600 -- this procedure to avoid recursive processing. ???
10602 Constrain_Discriminated_Type
10603 (Desig_Subtype, S, Related_Nod, For_Access => True);
10607 if (Ekind (T) = E_General_Access_Type
10608 or else Ada_Version >= Ada_2005)
10609 and then Has_Private_Declaration (Desig_Type)
10610 and then In_Open_Scopes (Scope (Desig_Type))
10611 and then Has_Discriminants (Desig_Type)
10613 -- Enforce rule that the constraint is illegal if there is
10614 -- an unconstrained view of the designated type. This means
10615 -- that the partial view (either a private type declaration or
10616 -- a derivation from a private type) has no discriminants.
10617 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
10618 -- by ACATS B371001).
10620 -- Rule updated for Ada 2005: the private type is said to have
10621 -- a constrained partial view, given that objects of the type
10622 -- can be declared. Furthermore, the rule applies to all access
10623 -- types, unlike the rule concerning default discriminants.
10626 Pack : constant Node_Id :=
10627 Unit_Declaration_Node (Scope (Desig_Type));
10632 if Nkind (Pack) = N_Package_Declaration then
10633 Decls := Visible_Declarations (Specification (Pack));
10634 Decl := First (Decls);
10635 while Present (Decl) loop
10636 if (Nkind (Decl) = N_Private_Type_Declaration
10638 Chars (Defining_Identifier (Decl)) =
10639 Chars (Desig_Type))
10642 (Nkind (Decl) = N_Full_Type_Declaration
10644 Chars (Defining_Identifier (Decl)) =
10646 and then Is_Derived_Type (Desig_Type)
10648 Has_Private_Declaration (Etype (Desig_Type)))
10650 if No (Discriminant_Specifications (Decl)) then
10652 ("cannot constrain general access type if " &
10653 "designated type has constrained partial view",
10666 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10667 For_Access => True);
10669 elsif (Is_Task_Type (Desig_Type)
10670 or else Is_Protected_Type (Desig_Type))
10671 and then not Is_Constrained (Desig_Type)
10673 Constrain_Concurrent
10674 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10677 Error_Msg_N ("invalid constraint on access type", S);
10678 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10679 Constraint_OK := False;
10682 if No (Def_Id) then
10683 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10685 Set_Ekind (Def_Id, E_Access_Subtype);
10688 if Constraint_OK then
10689 Set_Etype (Def_Id, Base_Type (T));
10691 if Is_Private_Type (Desig_Type) then
10692 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10695 Set_Etype (Def_Id, Any_Type);
10698 Set_Size_Info (Def_Id, T);
10699 Set_Is_Constrained (Def_Id, Constraint_OK);
10700 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10701 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10702 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10704 Conditional_Delay (Def_Id, T);
10706 -- AI-363 : Subtypes of general access types whose designated types have
10707 -- default discriminants are disallowed. In instances, the rule has to
10708 -- be checked against the actual, of which T is the subtype. In a
10709 -- generic body, the rule is checked assuming that the actual type has
10710 -- defaulted discriminants.
10712 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10713 if Ekind (Base_Type (T)) = E_General_Access_Type
10714 and then Has_Defaulted_Discriminants (Desig_Type)
10716 if Ada_Version < Ada_2005 then
10718 ("access subtype of general access type would not " &
10719 "be allowed in Ada 2005?", S);
10722 ("access subtype of general access type not allowed", S);
10725 Error_Msg_N ("\discriminants have defaults", S);
10727 elsif Is_Access_Type (T)
10728 and then Is_Generic_Type (Desig_Type)
10729 and then Has_Discriminants (Desig_Type)
10730 and then In_Package_Body (Current_Scope)
10732 if Ada_Version < Ada_2005 then
10734 ("access subtype would not be allowed in generic body " &
10735 "in Ada 2005?", S);
10738 ("access subtype not allowed in generic body", S);
10742 ("\designated type is a discriminated formal", S);
10745 end Constrain_Access;
10747 ---------------------
10748 -- Constrain_Array --
10749 ---------------------
10751 procedure Constrain_Array
10752 (Def_Id : in out Entity_Id;
10754 Related_Nod : Node_Id;
10755 Related_Id : Entity_Id;
10756 Suffix : Character)
10758 C : constant Node_Id := Constraint (SI);
10759 Number_Of_Constraints : Nat := 0;
10762 Constraint_OK : Boolean := True;
10765 T := Entity (Subtype_Mark (SI));
10767 if Ekind (T) in Access_Kind then
10768 T := Designated_Type (T);
10771 -- If an index constraint follows a subtype mark in a subtype indication
10772 -- then the type or subtype denoted by the subtype mark must not already
10773 -- impose an index constraint. The subtype mark must denote either an
10774 -- unconstrained array type or an access type whose designated type
10775 -- is such an array type... (RM 3.6.1)
10777 if Is_Constrained (T) then
10778 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10779 Constraint_OK := False;
10782 S := First (Constraints (C));
10783 while Present (S) loop
10784 Number_Of_Constraints := Number_Of_Constraints + 1;
10788 -- In either case, the index constraint must provide a discrete
10789 -- range for each index of the array type and the type of each
10790 -- discrete range must be the same as that of the corresponding
10791 -- index. (RM 3.6.1)
10793 if Number_Of_Constraints /= Number_Dimensions (T) then
10794 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10795 Constraint_OK := False;
10798 S := First (Constraints (C));
10799 Index := First_Index (T);
10802 -- Apply constraints to each index type
10804 for J in 1 .. Number_Of_Constraints loop
10805 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10813 if No (Def_Id) then
10815 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10816 Set_Parent (Def_Id, Related_Nod);
10819 Set_Ekind (Def_Id, E_Array_Subtype);
10822 Set_Size_Info (Def_Id, (T));
10823 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10824 Set_Etype (Def_Id, Base_Type (T));
10826 if Constraint_OK then
10827 Set_First_Index (Def_Id, First (Constraints (C)));
10829 Set_First_Index (Def_Id, First_Index (T));
10832 Set_Is_Constrained (Def_Id, True);
10833 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10834 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10836 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10837 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10839 -- A subtype does not inherit the packed_array_type of is parent. We
10840 -- need to initialize the attribute because if Def_Id is previously
10841 -- analyzed through a limited_with clause, it will have the attributes
10842 -- of an incomplete type, one of which is an Elist that overlaps the
10843 -- Packed_Array_Type field.
10845 Set_Packed_Array_Type (Def_Id, Empty);
10847 -- Build a freeze node if parent still needs one. Also make sure that
10848 -- the Depends_On_Private status is set because the subtype will need
10849 -- reprocessing at the time the base type does, and also we must set a
10850 -- conditional delay.
10852 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10853 Conditional_Delay (Def_Id, T);
10854 end Constrain_Array;
10856 ------------------------------
10857 -- Constrain_Component_Type --
10858 ------------------------------
10860 function Constrain_Component_Type
10862 Constrained_Typ : Entity_Id;
10863 Related_Node : Node_Id;
10865 Constraints : Elist_Id) return Entity_Id
10867 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10868 Compon_Type : constant Entity_Id := Etype (Comp);
10870 function Build_Constrained_Array_Type
10871 (Old_Type : Entity_Id) return Entity_Id;
10872 -- If Old_Type is an array type, one of whose indexes is constrained
10873 -- by a discriminant, build an Itype whose constraint replaces the
10874 -- discriminant with its value in the constraint.
10876 function Build_Constrained_Discriminated_Type
10877 (Old_Type : Entity_Id) return Entity_Id;
10878 -- Ditto for record components
10880 function Build_Constrained_Access_Type
10881 (Old_Type : Entity_Id) return Entity_Id;
10882 -- Ditto for access types. Makes use of previous two functions, to
10883 -- constrain designated type.
10885 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10886 -- T is an array or discriminated type, C is a list of constraints
10887 -- that apply to T. This routine builds the constrained subtype.
10889 function Is_Discriminant (Expr : Node_Id) return Boolean;
10890 -- Returns True if Expr is a discriminant
10892 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10893 -- Find the value of discriminant Discrim in Constraint
10895 -----------------------------------
10896 -- Build_Constrained_Access_Type --
10897 -----------------------------------
10899 function Build_Constrained_Access_Type
10900 (Old_Type : Entity_Id) return Entity_Id
10902 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10904 Desig_Subtype : Entity_Id;
10908 -- if the original access type was not embedded in the enclosing
10909 -- type definition, there is no need to produce a new access
10910 -- subtype. In fact every access type with an explicit constraint
10911 -- generates an itype whose scope is the enclosing record.
10913 if not Is_Type (Scope (Old_Type)) then
10916 elsif Is_Array_Type (Desig_Type) then
10917 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10919 elsif Has_Discriminants (Desig_Type) then
10921 -- This may be an access type to an enclosing record type for
10922 -- which we are constructing the constrained components. Return
10923 -- the enclosing record subtype. This is not always correct,
10924 -- but avoids infinite recursion. ???
10926 Desig_Subtype := Any_Type;
10928 for J in reverse 0 .. Scope_Stack.Last loop
10929 Scop := Scope_Stack.Table (J).Entity;
10932 and then Base_Type (Scop) = Base_Type (Desig_Type)
10934 Desig_Subtype := Scop;
10937 exit when not Is_Type (Scop);
10940 if Desig_Subtype = Any_Type then
10942 Build_Constrained_Discriminated_Type (Desig_Type);
10949 if Desig_Subtype /= Desig_Type then
10951 -- The Related_Node better be here or else we won't be able
10952 -- to attach new itypes to a node in the tree.
10954 pragma Assert (Present (Related_Node));
10956 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10958 Set_Etype (Itype, Base_Type (Old_Type));
10959 Set_Size_Info (Itype, (Old_Type));
10960 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10961 Set_Depends_On_Private (Itype, Has_Private_Component
10963 Set_Is_Access_Constant (Itype, Is_Access_Constant
10966 -- The new itype needs freezing when it depends on a not frozen
10967 -- type and the enclosing subtype needs freezing.
10969 if Has_Delayed_Freeze (Constrained_Typ)
10970 and then not Is_Frozen (Constrained_Typ)
10972 Conditional_Delay (Itype, Base_Type (Old_Type));
10980 end Build_Constrained_Access_Type;
10982 ----------------------------------
10983 -- Build_Constrained_Array_Type --
10984 ----------------------------------
10986 function Build_Constrained_Array_Type
10987 (Old_Type : Entity_Id) return Entity_Id
10991 Old_Index : Node_Id;
10992 Range_Node : Node_Id;
10993 Constr_List : List_Id;
10995 Need_To_Create_Itype : Boolean := False;
10998 Old_Index := First_Index (Old_Type);
10999 while Present (Old_Index) loop
11000 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11002 if Is_Discriminant (Lo_Expr)
11003 or else Is_Discriminant (Hi_Expr)
11005 Need_To_Create_Itype := True;
11008 Next_Index (Old_Index);
11011 if Need_To_Create_Itype then
11012 Constr_List := New_List;
11014 Old_Index := First_Index (Old_Type);
11015 while Present (Old_Index) loop
11016 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11018 if Is_Discriminant (Lo_Expr) then
11019 Lo_Expr := Get_Discr_Value (Lo_Expr);
11022 if Is_Discriminant (Hi_Expr) then
11023 Hi_Expr := Get_Discr_Value (Hi_Expr);
11028 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11030 Append (Range_Node, To => Constr_List);
11032 Next_Index (Old_Index);
11035 return Build_Subtype (Old_Type, Constr_List);
11040 end Build_Constrained_Array_Type;
11042 ------------------------------------------
11043 -- Build_Constrained_Discriminated_Type --
11044 ------------------------------------------
11046 function Build_Constrained_Discriminated_Type
11047 (Old_Type : Entity_Id) return Entity_Id
11050 Constr_List : List_Id;
11051 Old_Constraint : Elmt_Id;
11053 Need_To_Create_Itype : Boolean := False;
11056 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11057 while Present (Old_Constraint) loop
11058 Expr := Node (Old_Constraint);
11060 if Is_Discriminant (Expr) then
11061 Need_To_Create_Itype := True;
11064 Next_Elmt (Old_Constraint);
11067 if Need_To_Create_Itype then
11068 Constr_List := New_List;
11070 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11071 while Present (Old_Constraint) loop
11072 Expr := Node (Old_Constraint);
11074 if Is_Discriminant (Expr) then
11075 Expr := Get_Discr_Value (Expr);
11078 Append (New_Copy_Tree (Expr), To => Constr_List);
11080 Next_Elmt (Old_Constraint);
11083 return Build_Subtype (Old_Type, Constr_List);
11088 end Build_Constrained_Discriminated_Type;
11090 -------------------
11091 -- Build_Subtype --
11092 -------------------
11094 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11096 Subtyp_Decl : Node_Id;
11097 Def_Id : Entity_Id;
11098 Btyp : Entity_Id := Base_Type (T);
11101 -- The Related_Node better be here or else we won't be able to
11102 -- attach new itypes to a node in the tree.
11104 pragma Assert (Present (Related_Node));
11106 -- If the view of the component's type is incomplete or private
11107 -- with unknown discriminants, then the constraint must be applied
11108 -- to the full type.
11110 if Has_Unknown_Discriminants (Btyp)
11111 and then Present (Underlying_Type (Btyp))
11113 Btyp := Underlying_Type (Btyp);
11117 Make_Subtype_Indication (Loc,
11118 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11119 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11121 Def_Id := Create_Itype (Ekind (T), Related_Node);
11124 Make_Subtype_Declaration (Loc,
11125 Defining_Identifier => Def_Id,
11126 Subtype_Indication => Indic);
11128 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11130 -- Itypes must be analyzed with checks off (see package Itypes)
11132 Analyze (Subtyp_Decl, Suppress => All_Checks);
11137 ---------------------
11138 -- Get_Discr_Value --
11139 ---------------------
11141 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11146 -- The discriminant may be declared for the type, in which case we
11147 -- find it by iterating over the list of discriminants. If the
11148 -- discriminant is inherited from a parent type, it appears as the
11149 -- corresponding discriminant of the current type. This will be the
11150 -- case when constraining an inherited component whose constraint is
11151 -- given by a discriminant of the parent.
11153 D := First_Discriminant (Typ);
11154 E := First_Elmt (Constraints);
11156 while Present (D) loop
11157 if D = Entity (Discrim)
11158 or else D = CR_Discriminant (Entity (Discrim))
11159 or else Corresponding_Discriminant (D) = Entity (Discrim)
11164 Next_Discriminant (D);
11168 -- The Corresponding_Discriminant mechanism is incomplete, because
11169 -- the correspondence between new and old discriminants is not one
11170 -- to one: one new discriminant can constrain several old ones. In
11171 -- that case, scan sequentially the stored_constraint, the list of
11172 -- discriminants of the parents, and the constraints.
11173 -- Previous code checked for the present of the Stored_Constraint
11174 -- list for the derived type, but did not use it at all. Should it
11175 -- be present when the component is a discriminated task type?
11177 if Is_Derived_Type (Typ)
11178 and then Scope (Entity (Discrim)) = Etype (Typ)
11180 D := First_Discriminant (Etype (Typ));
11181 E := First_Elmt (Constraints);
11182 while Present (D) loop
11183 if D = Entity (Discrim) then
11187 Next_Discriminant (D);
11192 -- Something is wrong if we did not find the value
11194 raise Program_Error;
11195 end Get_Discr_Value;
11197 ---------------------
11198 -- Is_Discriminant --
11199 ---------------------
11201 function Is_Discriminant (Expr : Node_Id) return Boolean is
11202 Discrim_Scope : Entity_Id;
11205 if Denotes_Discriminant (Expr) then
11206 Discrim_Scope := Scope (Entity (Expr));
11208 -- Either we have a reference to one of Typ's discriminants,
11210 pragma Assert (Discrim_Scope = Typ
11212 -- or to the discriminants of the parent type, in the case
11213 -- of a derivation of a tagged type with variants.
11215 or else Discrim_Scope = Etype (Typ)
11216 or else Full_View (Discrim_Scope) = Etype (Typ)
11218 -- or same as above for the case where the discriminants
11219 -- were declared in Typ's private view.
11221 or else (Is_Private_Type (Discrim_Scope)
11222 and then Chars (Discrim_Scope) = Chars (Typ))
11224 -- or else we are deriving from the full view and the
11225 -- discriminant is declared in the private entity.
11227 or else (Is_Private_Type (Typ)
11228 and then Chars (Discrim_Scope) = Chars (Typ))
11230 -- Or we are constrained the corresponding record of a
11231 -- synchronized type that completes a private declaration.
11233 or else (Is_Concurrent_Record_Type (Typ)
11235 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11237 -- or we have a class-wide type, in which case make sure the
11238 -- discriminant found belongs to the root type.
11240 or else (Is_Class_Wide_Type (Typ)
11241 and then Etype (Typ) = Discrim_Scope));
11246 -- In all other cases we have something wrong
11249 end Is_Discriminant;
11251 -- Start of processing for Constrain_Component_Type
11254 if Nkind (Parent (Comp)) = N_Component_Declaration
11255 and then Comes_From_Source (Parent (Comp))
11256 and then Comes_From_Source
11257 (Subtype_Indication (Component_Definition (Parent (Comp))))
11260 (Subtype_Indication (Component_Definition (Parent (Comp))))
11262 return Compon_Type;
11264 elsif Is_Array_Type (Compon_Type) then
11265 return Build_Constrained_Array_Type (Compon_Type);
11267 elsif Has_Discriminants (Compon_Type) then
11268 return Build_Constrained_Discriminated_Type (Compon_Type);
11270 elsif Is_Access_Type (Compon_Type) then
11271 return Build_Constrained_Access_Type (Compon_Type);
11274 return Compon_Type;
11276 end Constrain_Component_Type;
11278 --------------------------
11279 -- Constrain_Concurrent --
11280 --------------------------
11282 -- For concurrent types, the associated record value type carries the same
11283 -- discriminants, so when we constrain a concurrent type, we must constrain
11284 -- the corresponding record type as well.
11286 procedure Constrain_Concurrent
11287 (Def_Id : in out Entity_Id;
11289 Related_Nod : Node_Id;
11290 Related_Id : Entity_Id;
11291 Suffix : Character)
11293 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
11297 if Ekind (T_Ent) in Access_Kind then
11298 T_Ent := Designated_Type (T_Ent);
11301 T_Val := Corresponding_Record_Type (T_Ent);
11303 if Present (T_Val) then
11305 if No (Def_Id) then
11306 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11309 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11311 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11312 Set_Corresponding_Record_Type (Def_Id,
11313 Constrain_Corresponding_Record
11314 (Def_Id, T_Val, Related_Nod, Related_Id));
11317 -- If there is no associated record, expansion is disabled and this
11318 -- is a generic context. Create a subtype in any case, so that
11319 -- semantic analysis can proceed.
11321 if No (Def_Id) then
11322 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11325 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11327 end Constrain_Concurrent;
11329 ------------------------------------
11330 -- Constrain_Corresponding_Record --
11331 ------------------------------------
11333 function Constrain_Corresponding_Record
11334 (Prot_Subt : Entity_Id;
11335 Corr_Rec : Entity_Id;
11336 Related_Nod : Node_Id;
11337 Related_Id : Entity_Id) return Entity_Id
11339 T_Sub : constant Entity_Id :=
11340 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11343 Set_Etype (T_Sub, Corr_Rec);
11344 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11345 Set_Is_Constrained (T_Sub, True);
11346 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11347 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11349 -- As elsewhere, we do not want to create a freeze node for this itype
11350 -- if it is created for a constrained component of an enclosing record
11351 -- because references to outer discriminants will appear out of scope.
11353 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11354 Conditional_Delay (T_Sub, Corr_Rec);
11356 Set_Is_Frozen (T_Sub);
11359 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11360 Set_Discriminant_Constraint
11361 (T_Sub, Discriminant_Constraint (Prot_Subt));
11362 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11363 Create_Constrained_Components
11364 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11367 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11370 end Constrain_Corresponding_Record;
11372 -----------------------
11373 -- Constrain_Decimal --
11374 -----------------------
11376 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11377 T : constant Entity_Id := Entity (Subtype_Mark (S));
11378 C : constant Node_Id := Constraint (S);
11379 Loc : constant Source_Ptr := Sloc (C);
11380 Range_Expr : Node_Id;
11381 Digits_Expr : Node_Id;
11386 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11388 if Nkind (C) = N_Range_Constraint then
11389 Range_Expr := Range_Expression (C);
11390 Digits_Val := Digits_Value (T);
11393 pragma Assert (Nkind (C) = N_Digits_Constraint);
11395 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11397 Digits_Expr := Digits_Expression (C);
11398 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11400 Check_Digits_Expression (Digits_Expr);
11401 Digits_Val := Expr_Value (Digits_Expr);
11403 if Digits_Val > Digits_Value (T) then
11405 ("digits expression is incompatible with subtype", C);
11406 Digits_Val := Digits_Value (T);
11409 if Present (Range_Constraint (C)) then
11410 Range_Expr := Range_Expression (Range_Constraint (C));
11412 Range_Expr := Empty;
11416 Set_Etype (Def_Id, Base_Type (T));
11417 Set_Size_Info (Def_Id, (T));
11418 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11419 Set_Delta_Value (Def_Id, Delta_Value (T));
11420 Set_Scale_Value (Def_Id, Scale_Value (T));
11421 Set_Small_Value (Def_Id, Small_Value (T));
11422 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11423 Set_Digits_Value (Def_Id, Digits_Val);
11425 -- Manufacture range from given digits value if no range present
11427 if No (Range_Expr) then
11428 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11432 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11434 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11437 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11438 Set_Discrete_RM_Size (Def_Id);
11440 -- Unconditionally delay the freeze, since we cannot set size
11441 -- information in all cases correctly until the freeze point.
11443 Set_Has_Delayed_Freeze (Def_Id);
11444 end Constrain_Decimal;
11446 ----------------------------------
11447 -- Constrain_Discriminated_Type --
11448 ----------------------------------
11450 procedure Constrain_Discriminated_Type
11451 (Def_Id : Entity_Id;
11453 Related_Nod : Node_Id;
11454 For_Access : Boolean := False)
11456 E : constant Entity_Id := Entity (Subtype_Mark (S));
11459 Elist : Elist_Id := New_Elmt_List;
11461 procedure Fixup_Bad_Constraint;
11462 -- This is called after finding a bad constraint, and after having
11463 -- posted an appropriate error message. The mission is to leave the
11464 -- entity T in as reasonable state as possible!
11466 --------------------------
11467 -- Fixup_Bad_Constraint --
11468 --------------------------
11470 procedure Fixup_Bad_Constraint is
11472 -- Set a reasonable Ekind for the entity. For an incomplete type,
11473 -- we can't do much, but for other types, we can set the proper
11474 -- corresponding subtype kind.
11476 if Ekind (T) = E_Incomplete_Type then
11477 Set_Ekind (Def_Id, Ekind (T));
11479 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11482 -- Set Etype to the known type, to reduce chances of cascaded errors
11484 Set_Etype (Def_Id, E);
11485 Set_Error_Posted (Def_Id);
11486 end Fixup_Bad_Constraint;
11488 -- Start of processing for Constrain_Discriminated_Type
11491 C := Constraint (S);
11493 -- A discriminant constraint is only allowed in a subtype indication,
11494 -- after a subtype mark. This subtype mark must denote either a type
11495 -- with discriminants, or an access type whose designated type is a
11496 -- type with discriminants. A discriminant constraint specifies the
11497 -- values of these discriminants (RM 3.7.2(5)).
11499 T := Base_Type (Entity (Subtype_Mark (S)));
11501 if Ekind (T) in Access_Kind then
11502 T := Designated_Type (T);
11505 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11506 -- Avoid generating an error for access-to-incomplete subtypes.
11508 if Ada_Version >= Ada_2005
11509 and then Ekind (T) = E_Incomplete_Type
11510 and then Nkind (Parent (S)) = N_Subtype_Declaration
11511 and then not Is_Itype (Def_Id)
11513 -- A little sanity check, emit an error message if the type
11514 -- has discriminants to begin with. Type T may be a regular
11515 -- incomplete type or imported via a limited with clause.
11517 if Has_Discriminants (T)
11519 (From_With_Type (T)
11520 and then Present (Non_Limited_View (T))
11521 and then Nkind (Parent (Non_Limited_View (T))) =
11522 N_Full_Type_Declaration
11523 and then Present (Discriminant_Specifications
11524 (Parent (Non_Limited_View (T)))))
11527 ("(Ada 2005) incomplete subtype may not be constrained", C);
11529 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11532 Fixup_Bad_Constraint;
11535 -- Check that the type has visible discriminants. The type may be
11536 -- a private type with unknown discriminants whose full view has
11537 -- discriminants which are invisible.
11539 elsif not Has_Discriminants (T)
11541 (Has_Unknown_Discriminants (T)
11542 and then Is_Private_Type (T))
11544 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11545 Fixup_Bad_Constraint;
11548 elsif Is_Constrained (E)
11549 or else (Ekind (E) = E_Class_Wide_Subtype
11550 and then Present (Discriminant_Constraint (E)))
11552 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11553 Fixup_Bad_Constraint;
11557 -- T may be an unconstrained subtype (e.g. a generic actual).
11558 -- Constraint applies to the base type.
11560 T := Base_Type (T);
11562 Elist := Build_Discriminant_Constraints (T, S);
11564 -- If the list returned was empty we had an error in building the
11565 -- discriminant constraint. We have also already signalled an error
11566 -- in the incomplete type case
11568 if Is_Empty_Elmt_List (Elist) then
11569 Fixup_Bad_Constraint;
11573 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11574 end Constrain_Discriminated_Type;
11576 ---------------------------
11577 -- Constrain_Enumeration --
11578 ---------------------------
11580 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11581 T : constant Entity_Id := Entity (Subtype_Mark (S));
11582 C : constant Node_Id := Constraint (S);
11585 -- By default, consider that the enumeration subtype is in ALFA if the
11586 -- entity of its subtype mark is in ALFA. This is reversed later if the
11587 -- range of the subtype is not static.
11589 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11590 and then Is_In_ALFA (T)
11592 Set_Is_In_ALFA (Def_Id);
11595 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11597 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11599 Set_Etype (Def_Id, Base_Type (T));
11600 Set_Size_Info (Def_Id, (T));
11601 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11602 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11604 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11606 Set_Discrete_RM_Size (Def_Id);
11607 end Constrain_Enumeration;
11609 ----------------------
11610 -- Constrain_Float --
11611 ----------------------
11613 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11614 T : constant Entity_Id := Entity (Subtype_Mark (S));
11620 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11622 Set_Etype (Def_Id, Base_Type (T));
11623 Set_Size_Info (Def_Id, (T));
11624 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11626 -- Process the constraint
11628 C := Constraint (S);
11630 -- Digits constraint present
11632 if Nkind (C) = N_Digits_Constraint then
11634 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11635 Check_Restriction (No_Obsolescent_Features, C);
11637 if Warn_On_Obsolescent_Feature then
11639 ("subtype digits constraint is an " &
11640 "obsolescent feature (RM J.3(8))?", C);
11643 D := Digits_Expression (C);
11644 Analyze_And_Resolve (D, Any_Integer);
11645 Check_Digits_Expression (D);
11646 Set_Digits_Value (Def_Id, Expr_Value (D));
11648 -- Check that digits value is in range. Obviously we can do this
11649 -- at compile time, but it is strictly a runtime check, and of
11650 -- course there is an ACVC test that checks this!
11652 if Digits_Value (Def_Id) > Digits_Value (T) then
11653 Error_Msg_Uint_1 := Digits_Value (T);
11654 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11656 Make_Raise_Constraint_Error (Sloc (D),
11657 Reason => CE_Range_Check_Failed);
11658 Insert_Action (Declaration_Node (Def_Id), Rais);
11661 C := Range_Constraint (C);
11663 -- No digits constraint present
11666 Set_Digits_Value (Def_Id, Digits_Value (T));
11669 -- Range constraint present
11671 if Nkind (C) = N_Range_Constraint then
11672 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11674 -- No range constraint present
11677 pragma Assert (No (C));
11678 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11681 Set_Is_Constrained (Def_Id);
11682 end Constrain_Float;
11684 ---------------------
11685 -- Constrain_Index --
11686 ---------------------
11688 procedure Constrain_Index
11691 Related_Nod : Node_Id;
11692 Related_Id : Entity_Id;
11693 Suffix : Character;
11694 Suffix_Index : Nat)
11696 Def_Id : Entity_Id;
11697 R : Node_Id := Empty;
11698 T : constant Entity_Id := Etype (Index);
11701 if Nkind (S) = N_Range
11703 (Nkind (S) = N_Attribute_Reference
11704 and then Attribute_Name (S) = Name_Range)
11706 -- A Range attribute will be transformed into N_Range by Resolve
11712 Process_Range_Expr_In_Decl (R, T, Empty_List);
11714 if not Error_Posted (S)
11716 (Nkind (S) /= N_Range
11717 or else not Covers (T, (Etype (Low_Bound (S))))
11718 or else not Covers (T, (Etype (High_Bound (S)))))
11720 if Base_Type (T) /= Any_Type
11721 and then Etype (Low_Bound (S)) /= Any_Type
11722 and then Etype (High_Bound (S)) /= Any_Type
11724 Error_Msg_N ("range expected", S);
11728 elsif Nkind (S) = N_Subtype_Indication then
11730 -- The parser has verified that this is a discrete indication
11732 Resolve_Discrete_Subtype_Indication (S, T);
11733 R := Range_Expression (Constraint (S));
11735 -- Capture values of bounds and generate temporaries for them if
11736 -- needed, since checks may cause duplication of the expressions
11737 -- which must not be reevaluated.
11739 if Expander_Active then
11740 Force_Evaluation (Low_Bound (R));
11741 Force_Evaluation (High_Bound (R));
11744 elsif Nkind (S) = N_Discriminant_Association then
11746 -- Syntactically valid in subtype indication
11748 Error_Msg_N ("invalid index constraint", S);
11749 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11752 -- Subtype_Mark case, no anonymous subtypes to construct
11757 if Is_Entity_Name (S) then
11758 if not Is_Type (Entity (S)) then
11759 Error_Msg_N ("expect subtype mark for index constraint", S);
11761 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11762 Wrong_Type (S, Base_Type (T));
11764 -- Check error of subtype with predicate in index constraint
11767 Bad_Predicated_Subtype_Use
11768 ("subtype& has predicate, not allowed in index constraint",
11775 Error_Msg_N ("invalid index constraint", S);
11776 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11782 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11784 Set_Etype (Def_Id, Base_Type (T));
11786 if Is_Modular_Integer_Type (T) then
11787 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11789 elsif Is_Integer_Type (T) then
11790 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11793 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11794 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11795 Set_First_Literal (Def_Id, First_Literal (T));
11798 Set_Size_Info (Def_Id, (T));
11799 Set_RM_Size (Def_Id, RM_Size (T));
11800 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11802 Set_Scalar_Range (Def_Id, R);
11804 Set_Etype (S, Def_Id);
11805 Set_Discrete_RM_Size (Def_Id);
11806 end Constrain_Index;
11808 -----------------------
11809 -- Constrain_Integer --
11810 -----------------------
11812 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11813 T : constant Entity_Id := Entity (Subtype_Mark (S));
11814 C : constant Node_Id := Constraint (S);
11817 -- By default, consider that the integer subtype is in ALFA if the
11818 -- entity of its subtype mark is in ALFA. This is reversed later if the
11819 -- range of the subtype is not static.
11821 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11822 and then Is_In_ALFA (T)
11824 Set_Is_In_ALFA (Def_Id);
11827 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11829 if Is_Modular_Integer_Type (T) then
11830 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11832 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11835 Set_Etype (Def_Id, Base_Type (T));
11836 Set_Size_Info (Def_Id, (T));
11837 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11838 Set_Discrete_RM_Size (Def_Id);
11839 end Constrain_Integer;
11841 ------------------------------
11842 -- Constrain_Ordinary_Fixed --
11843 ------------------------------
11845 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11846 T : constant Entity_Id := Entity (Subtype_Mark (S));
11852 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11853 Set_Etype (Def_Id, Base_Type (T));
11854 Set_Size_Info (Def_Id, (T));
11855 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11856 Set_Small_Value (Def_Id, Small_Value (T));
11858 -- Process the constraint
11860 C := Constraint (S);
11862 -- Delta constraint present
11864 if Nkind (C) = N_Delta_Constraint then
11866 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11867 Check_Restriction (No_Obsolescent_Features, C);
11869 if Warn_On_Obsolescent_Feature then
11871 ("subtype delta constraint is an " &
11872 "obsolescent feature (RM J.3(7))?");
11875 D := Delta_Expression (C);
11876 Analyze_And_Resolve (D, Any_Real);
11877 Check_Delta_Expression (D);
11878 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11880 -- Check that delta value is in range. Obviously we can do this
11881 -- at compile time, but it is strictly a runtime check, and of
11882 -- course there is an ACVC test that checks this!
11884 if Delta_Value (Def_Id) < Delta_Value (T) then
11885 Error_Msg_N ("?delta value is too small", D);
11887 Make_Raise_Constraint_Error (Sloc (D),
11888 Reason => CE_Range_Check_Failed);
11889 Insert_Action (Declaration_Node (Def_Id), Rais);
11892 C := Range_Constraint (C);
11894 -- No delta constraint present
11897 Set_Delta_Value (Def_Id, Delta_Value (T));
11900 -- Range constraint present
11902 if Nkind (C) = N_Range_Constraint then
11903 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11905 -- No range constraint present
11908 pragma Assert (No (C));
11909 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11913 Set_Discrete_RM_Size (Def_Id);
11915 -- Unconditionally delay the freeze, since we cannot set size
11916 -- information in all cases correctly until the freeze point.
11918 Set_Has_Delayed_Freeze (Def_Id);
11919 end Constrain_Ordinary_Fixed;
11921 -----------------------
11922 -- Contain_Interface --
11923 -----------------------
11925 function Contain_Interface
11926 (Iface : Entity_Id;
11927 Ifaces : Elist_Id) return Boolean
11929 Iface_Elmt : Elmt_Id;
11932 if Present (Ifaces) then
11933 Iface_Elmt := First_Elmt (Ifaces);
11934 while Present (Iface_Elmt) loop
11935 if Node (Iface_Elmt) = Iface then
11939 Next_Elmt (Iface_Elmt);
11944 end Contain_Interface;
11946 ---------------------------
11947 -- Convert_Scalar_Bounds --
11948 ---------------------------
11950 procedure Convert_Scalar_Bounds
11952 Parent_Type : Entity_Id;
11953 Derived_Type : Entity_Id;
11956 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11963 -- Defend against previous errors
11965 if No (Scalar_Range (Derived_Type)) then
11969 Lo := Build_Scalar_Bound
11970 (Type_Low_Bound (Derived_Type),
11971 Parent_Type, Implicit_Base);
11973 Hi := Build_Scalar_Bound
11974 (Type_High_Bound (Derived_Type),
11975 Parent_Type, Implicit_Base);
11982 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11984 Set_Parent (Rng, N);
11985 Set_Scalar_Range (Derived_Type, Rng);
11987 -- Analyze the bounds
11989 Analyze_And_Resolve (Lo, Implicit_Base);
11990 Analyze_And_Resolve (Hi, Implicit_Base);
11992 -- Analyze the range itself, except that we do not analyze it if
11993 -- the bounds are real literals, and we have a fixed-point type.
11994 -- The reason for this is that we delay setting the bounds in this
11995 -- case till we know the final Small and Size values (see circuit
11996 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11998 if Is_Fixed_Point_Type (Parent_Type)
11999 and then Nkind (Lo) = N_Real_Literal
12000 and then Nkind (Hi) = N_Real_Literal
12004 -- Here we do the analysis of the range
12006 -- Note: we do this manually, since if we do a normal Analyze and
12007 -- Resolve call, there are problems with the conversions used for
12008 -- the derived type range.
12011 Set_Etype (Rng, Implicit_Base);
12012 Set_Analyzed (Rng, True);
12014 end Convert_Scalar_Bounds;
12016 -------------------
12017 -- Copy_And_Swap --
12018 -------------------
12020 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12022 -- Initialize new full declaration entity by copying the pertinent
12023 -- fields of the corresponding private declaration entity.
12025 -- We temporarily set Ekind to a value appropriate for a type to
12026 -- avoid assert failures in Einfo from checking for setting type
12027 -- attributes on something that is not a type. Ekind (Priv) is an
12028 -- appropriate choice, since it allowed the attributes to be set
12029 -- in the first place. This Ekind value will be modified later.
12031 Set_Ekind (Full, Ekind (Priv));
12033 -- Also set Etype temporarily to Any_Type, again, in the absence
12034 -- of errors, it will be properly reset, and if there are errors,
12035 -- then we want a value of Any_Type to remain.
12037 Set_Etype (Full, Any_Type);
12039 -- Now start copying attributes
12041 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12043 if Has_Discriminants (Full) then
12044 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12045 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12048 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12049 Set_Homonym (Full, Homonym (Priv));
12050 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12051 Set_Is_Public (Full, Is_Public (Priv));
12052 Set_Is_Pure (Full, Is_Pure (Priv));
12053 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12054 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12055 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12056 Set_Has_Pragma_Unreferenced_Objects
12057 (Full, Has_Pragma_Unreferenced_Objects
12060 Conditional_Delay (Full, Priv);
12062 if Is_Tagged_Type (Full) then
12063 Set_Direct_Primitive_Operations (Full,
12064 Direct_Primitive_Operations (Priv));
12066 if Is_Base_Type (Priv) then
12067 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12071 Set_Is_Volatile (Full, Is_Volatile (Priv));
12072 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12073 Set_Scope (Full, Scope (Priv));
12074 Set_Next_Entity (Full, Next_Entity (Priv));
12075 Set_First_Entity (Full, First_Entity (Priv));
12076 Set_Last_Entity (Full, Last_Entity (Priv));
12078 -- If access types have been recorded for later handling, keep them in
12079 -- the full view so that they get handled when the full view freeze
12080 -- node is expanded.
12082 if Present (Freeze_Node (Priv))
12083 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12085 Ensure_Freeze_Node (Full);
12086 Set_Access_Types_To_Process
12087 (Freeze_Node (Full),
12088 Access_Types_To_Process (Freeze_Node (Priv)));
12091 -- Swap the two entities. Now Private is the full type entity and Full
12092 -- is the private one. They will be swapped back at the end of the
12093 -- private part. This swapping ensures that the entity that is visible
12094 -- in the private part is the full declaration.
12096 Exchange_Entities (Priv, Full);
12097 Append_Entity (Full, Scope (Full));
12100 -------------------------------------
12101 -- Copy_Array_Base_Type_Attributes --
12102 -------------------------------------
12104 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12106 Set_Component_Alignment (T1, Component_Alignment (T2));
12107 Set_Component_Type (T1, Component_Type (T2));
12108 Set_Component_Size (T1, Component_Size (T2));
12109 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12110 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12111 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12112 Set_Has_Task (T1, Has_Task (T2));
12113 Set_Is_Packed (T1, Is_Packed (T2));
12114 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12115 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12116 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12117 end Copy_Array_Base_Type_Attributes;
12119 -----------------------------------
12120 -- Copy_Array_Subtype_Attributes --
12121 -----------------------------------
12123 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12125 Set_Size_Info (T1, T2);
12127 Set_First_Index (T1, First_Index (T2));
12128 Set_Is_Aliased (T1, Is_Aliased (T2));
12129 Set_Is_Atomic (T1, Is_Atomic (T2));
12130 Set_Is_Volatile (T1, Is_Volatile (T2));
12131 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12132 Set_Is_Constrained (T1, Is_Constrained (T2));
12133 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12134 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12135 Set_Convention (T1, Convention (T2));
12136 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12137 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12138 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12139 end Copy_Array_Subtype_Attributes;
12141 -----------------------------------
12142 -- Create_Constrained_Components --
12143 -----------------------------------
12145 procedure Create_Constrained_Components
12147 Decl_Node : Node_Id;
12149 Constraints : Elist_Id)
12151 Loc : constant Source_Ptr := Sloc (Subt);
12152 Comp_List : constant Elist_Id := New_Elmt_List;
12153 Parent_Type : constant Entity_Id := Etype (Typ);
12154 Assoc_List : constant List_Id := New_List;
12155 Discr_Val : Elmt_Id;
12159 Is_Static : Boolean := True;
12161 procedure Collect_Fixed_Components (Typ : Entity_Id);
12162 -- Collect parent type components that do not appear in a variant part
12164 procedure Create_All_Components;
12165 -- Iterate over Comp_List to create the components of the subtype
12167 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12168 -- Creates a new component from Old_Compon, copying all the fields from
12169 -- it, including its Etype, inserts the new component in the Subt entity
12170 -- chain and returns the new component.
12172 function Is_Variant_Record (T : Entity_Id) return Boolean;
12173 -- If true, and discriminants are static, collect only components from
12174 -- variants selected by discriminant values.
12176 ------------------------------
12177 -- Collect_Fixed_Components --
12178 ------------------------------
12180 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12182 -- Build association list for discriminants, and find components of the
12183 -- variant part selected by the values of the discriminants.
12185 Old_C := First_Discriminant (Typ);
12186 Discr_Val := First_Elmt (Constraints);
12187 while Present (Old_C) loop
12188 Append_To (Assoc_List,
12189 Make_Component_Association (Loc,
12190 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12191 Expression => New_Copy (Node (Discr_Val))));
12193 Next_Elmt (Discr_Val);
12194 Next_Discriminant (Old_C);
12197 -- The tag, and the possible parent and controller components
12198 -- are unconditionally in the subtype.
12200 if Is_Tagged_Type (Typ)
12201 or else Has_Controlled_Component (Typ)
12203 Old_C := First_Component (Typ);
12204 while Present (Old_C) loop
12205 if Chars ((Old_C)) = Name_uTag
12206 or else Chars ((Old_C)) = Name_uParent
12207 or else Chars ((Old_C)) = Name_uController
12209 Append_Elmt (Old_C, Comp_List);
12212 Next_Component (Old_C);
12215 end Collect_Fixed_Components;
12217 ---------------------------
12218 -- Create_All_Components --
12219 ---------------------------
12221 procedure Create_All_Components is
12225 Comp := First_Elmt (Comp_List);
12226 while Present (Comp) loop
12227 Old_C := Node (Comp);
12228 New_C := Create_Component (Old_C);
12232 Constrain_Component_Type
12233 (Old_C, Subt, Decl_Node, Typ, Constraints));
12234 Set_Is_Public (New_C, Is_Public (Subt));
12238 end Create_All_Components;
12240 ----------------------
12241 -- Create_Component --
12242 ----------------------
12244 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12245 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12248 if Ekind (Old_Compon) = E_Discriminant
12249 and then Is_Completely_Hidden (Old_Compon)
12251 -- This is a shadow discriminant created for a discriminant of
12252 -- the parent type, which needs to be present in the subtype.
12253 -- Give the shadow discriminant an internal name that cannot
12254 -- conflict with that of visible components.
12256 Set_Chars (New_Compon, New_Internal_Name ('C'));
12259 -- Set the parent so we have a proper link for freezing etc. This is
12260 -- not a real parent pointer, since of course our parent does not own
12261 -- up to us and reference us, we are an illegitimate child of the
12262 -- original parent!
12264 Set_Parent (New_Compon, Parent (Old_Compon));
12266 -- If the old component's Esize was already determined and is a
12267 -- static value, then the new component simply inherits it. Otherwise
12268 -- the old component's size may require run-time determination, but
12269 -- the new component's size still might be statically determinable
12270 -- (if, for example it has a static constraint). In that case we want
12271 -- Layout_Type to recompute the component's size, so we reset its
12272 -- size and positional fields.
12274 if Frontend_Layout_On_Target
12275 and then not Known_Static_Esize (Old_Compon)
12277 Set_Esize (New_Compon, Uint_0);
12278 Init_Normalized_First_Bit (New_Compon);
12279 Init_Normalized_Position (New_Compon);
12280 Init_Normalized_Position_Max (New_Compon);
12283 -- We do not want this node marked as Comes_From_Source, since
12284 -- otherwise it would get first class status and a separate cross-
12285 -- reference line would be generated. Illegitimate children do not
12286 -- rate such recognition.
12288 Set_Comes_From_Source (New_Compon, False);
12290 -- But it is a real entity, and a birth certificate must be properly
12291 -- registered by entering it into the entity list.
12293 Enter_Name (New_Compon);
12296 end Create_Component;
12298 -----------------------
12299 -- Is_Variant_Record --
12300 -----------------------
12302 function Is_Variant_Record (T : Entity_Id) return Boolean is
12304 return Nkind (Parent (T)) = N_Full_Type_Declaration
12305 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12306 and then Present (Component_List (Type_Definition (Parent (T))))
12309 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12310 end Is_Variant_Record;
12312 -- Start of processing for Create_Constrained_Components
12315 pragma Assert (Subt /= Base_Type (Subt));
12316 pragma Assert (Typ = Base_Type (Typ));
12318 Set_First_Entity (Subt, Empty);
12319 Set_Last_Entity (Subt, Empty);
12321 -- Check whether constraint is fully static, in which case we can
12322 -- optimize the list of components.
12324 Discr_Val := First_Elmt (Constraints);
12325 while Present (Discr_Val) loop
12326 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12327 Is_Static := False;
12331 Next_Elmt (Discr_Val);
12334 Set_Has_Static_Discriminants (Subt, Is_Static);
12338 -- Inherit the discriminants of the parent type
12340 Add_Discriminants : declare
12346 Old_C := First_Discriminant (Typ);
12348 while Present (Old_C) loop
12349 Num_Disc := Num_Disc + 1;
12350 New_C := Create_Component (Old_C);
12351 Set_Is_Public (New_C, Is_Public (Subt));
12352 Next_Discriminant (Old_C);
12355 -- For an untagged derived subtype, the number of discriminants may
12356 -- be smaller than the number of inherited discriminants, because
12357 -- several of them may be renamed by a single new discriminant or
12358 -- constrained. In this case, add the hidden discriminants back into
12359 -- the subtype, because they need to be present if the optimizer of
12360 -- the GCC 4.x back-end decides to break apart assignments between
12361 -- objects using the parent view into member-wise assignments.
12365 if Is_Derived_Type (Typ)
12366 and then not Is_Tagged_Type (Typ)
12368 Old_C := First_Stored_Discriminant (Typ);
12370 while Present (Old_C) loop
12371 Num_Gird := Num_Gird + 1;
12372 Next_Stored_Discriminant (Old_C);
12376 if Num_Gird > Num_Disc then
12378 -- Find out multiple uses of new discriminants, and add hidden
12379 -- components for the extra renamed discriminants. We recognize
12380 -- multiple uses through the Corresponding_Discriminant of a
12381 -- new discriminant: if it constrains several old discriminants,
12382 -- this field points to the last one in the parent type. The
12383 -- stored discriminants of the derived type have the same name
12384 -- as those of the parent.
12388 New_Discr : Entity_Id;
12389 Old_Discr : Entity_Id;
12392 Constr := First_Elmt (Stored_Constraint (Typ));
12393 Old_Discr := First_Stored_Discriminant (Typ);
12394 while Present (Constr) loop
12395 if Is_Entity_Name (Node (Constr))
12396 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12398 New_Discr := Entity (Node (Constr));
12400 if Chars (Corresponding_Discriminant (New_Discr)) /=
12403 -- The new discriminant has been used to rename a
12404 -- subsequent old discriminant. Introduce a shadow
12405 -- component for the current old discriminant.
12407 New_C := Create_Component (Old_Discr);
12408 Set_Original_Record_Component (New_C, Old_Discr);
12412 -- The constraint has eliminated the old discriminant.
12413 -- Introduce a shadow component.
12415 New_C := Create_Component (Old_Discr);
12416 Set_Original_Record_Component (New_C, Old_Discr);
12419 Next_Elmt (Constr);
12420 Next_Stored_Discriminant (Old_Discr);
12424 end Add_Discriminants;
12427 and then Is_Variant_Record (Typ)
12429 Collect_Fixed_Components (Typ);
12431 Gather_Components (
12433 Component_List (Type_Definition (Parent (Typ))),
12434 Governed_By => Assoc_List,
12436 Report_Errors => Errors);
12437 pragma Assert (not Errors);
12439 Create_All_Components;
12441 -- If the subtype declaration is created for a tagged type derivation
12442 -- with constraints, we retrieve the record definition of the parent
12443 -- type to select the components of the proper variant.
12446 and then Is_Tagged_Type (Typ)
12447 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12449 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12450 and then Is_Variant_Record (Parent_Type)
12452 Collect_Fixed_Components (Typ);
12454 Gather_Components (
12456 Component_List (Type_Definition (Parent (Parent_Type))),
12457 Governed_By => Assoc_List,
12459 Report_Errors => Errors);
12460 pragma Assert (not Errors);
12462 -- If the tagged derivation has a type extension, collect all the
12463 -- new components therein.
12466 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12468 Old_C := First_Component (Typ);
12469 while Present (Old_C) loop
12470 if Original_Record_Component (Old_C) = Old_C
12471 and then Chars (Old_C) /= Name_uTag
12472 and then Chars (Old_C) /= Name_uParent
12473 and then Chars (Old_C) /= Name_uController
12475 Append_Elmt (Old_C, Comp_List);
12478 Next_Component (Old_C);
12482 Create_All_Components;
12485 -- If discriminants are not static, or if this is a multi-level type
12486 -- extension, we have to include all components of the parent type.
12488 Old_C := First_Component (Typ);
12489 while Present (Old_C) loop
12490 New_C := Create_Component (Old_C);
12494 Constrain_Component_Type
12495 (Old_C, Subt, Decl_Node, Typ, Constraints));
12496 Set_Is_Public (New_C, Is_Public (Subt));
12498 Next_Component (Old_C);
12503 end Create_Constrained_Components;
12505 ------------------------------------------
12506 -- Decimal_Fixed_Point_Type_Declaration --
12507 ------------------------------------------
12509 procedure Decimal_Fixed_Point_Type_Declaration
12513 Loc : constant Source_Ptr := Sloc (Def);
12514 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12515 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12516 Implicit_Base : Entity_Id;
12523 Check_SPARK_Restriction
12524 ("decimal fixed point type is not allowed", Def);
12525 Check_Restriction (No_Fixed_Point, Def);
12527 -- Create implicit base type
12530 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12531 Set_Etype (Implicit_Base, Implicit_Base);
12533 -- Analyze and process delta expression
12535 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12537 Check_Delta_Expression (Delta_Expr);
12538 Delta_Val := Expr_Value_R (Delta_Expr);
12540 -- Check delta is power of 10, and determine scale value from it
12546 Scale_Val := Uint_0;
12549 if Val < Ureal_1 then
12550 while Val < Ureal_1 loop
12551 Val := Val * Ureal_10;
12552 Scale_Val := Scale_Val + 1;
12555 if Scale_Val > 18 then
12556 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12557 Scale_Val := UI_From_Int (+18);
12561 while Val > Ureal_1 loop
12562 Val := Val / Ureal_10;
12563 Scale_Val := Scale_Val - 1;
12566 if Scale_Val < -18 then
12567 Error_Msg_N ("scale is less than minimum value of -18", Def);
12568 Scale_Val := UI_From_Int (-18);
12572 if Val /= Ureal_1 then
12573 Error_Msg_N ("delta expression must be a power of 10", Def);
12574 Delta_Val := Ureal_10 ** (-Scale_Val);
12578 -- Set delta, scale and small (small = delta for decimal type)
12580 Set_Delta_Value (Implicit_Base, Delta_Val);
12581 Set_Scale_Value (Implicit_Base, Scale_Val);
12582 Set_Small_Value (Implicit_Base, Delta_Val);
12584 -- Analyze and process digits expression
12586 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12587 Check_Digits_Expression (Digs_Expr);
12588 Digs_Val := Expr_Value (Digs_Expr);
12590 if Digs_Val > 18 then
12591 Digs_Val := UI_From_Int (+18);
12592 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12595 Set_Digits_Value (Implicit_Base, Digs_Val);
12596 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12598 -- Set range of base type from digits value for now. This will be
12599 -- expanded to represent the true underlying base range by Freeze.
12601 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12603 -- Note: We leave size as zero for now, size will be set at freeze
12604 -- time. We have to do this for ordinary fixed-point, because the size
12605 -- depends on the specified small, and we might as well do the same for
12606 -- decimal fixed-point.
12608 pragma Assert (Esize (Implicit_Base) = Uint_0);
12610 -- If there are bounds given in the declaration use them as the
12611 -- bounds of the first named subtype.
12613 if Present (Real_Range_Specification (Def)) then
12615 RRS : constant Node_Id := Real_Range_Specification (Def);
12616 Low : constant Node_Id := Low_Bound (RRS);
12617 High : constant Node_Id := High_Bound (RRS);
12622 Analyze_And_Resolve (Low, Any_Real);
12623 Analyze_And_Resolve (High, Any_Real);
12624 Check_Real_Bound (Low);
12625 Check_Real_Bound (High);
12626 Low_Val := Expr_Value_R (Low);
12627 High_Val := Expr_Value_R (High);
12629 if Low_Val < (-Bound_Val) then
12631 ("range low bound too small for digits value", Low);
12632 Low_Val := -Bound_Val;
12635 if High_Val > Bound_Val then
12637 ("range high bound too large for digits value", High);
12638 High_Val := Bound_Val;
12641 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12644 -- If no explicit range, use range that corresponds to given
12645 -- digits value. This will end up as the final range for the
12649 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12652 -- Complete entity for first subtype
12654 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12655 Set_Etype (T, Implicit_Base);
12656 Set_Size_Info (T, Implicit_Base);
12657 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12658 Set_Digits_Value (T, Digs_Val);
12659 Set_Delta_Value (T, Delta_Val);
12660 Set_Small_Value (T, Delta_Val);
12661 Set_Scale_Value (T, Scale_Val);
12662 Set_Is_Constrained (T);
12663 end Decimal_Fixed_Point_Type_Declaration;
12665 -----------------------------------
12666 -- Derive_Progenitor_Subprograms --
12667 -----------------------------------
12669 procedure Derive_Progenitor_Subprograms
12670 (Parent_Type : Entity_Id;
12671 Tagged_Type : Entity_Id)
12676 Iface_Elmt : Elmt_Id;
12677 Iface_Subp : Entity_Id;
12678 New_Subp : Entity_Id := Empty;
12679 Prim_Elmt : Elmt_Id;
12684 pragma Assert (Ada_Version >= Ada_2005
12685 and then Is_Record_Type (Tagged_Type)
12686 and then Is_Tagged_Type (Tagged_Type)
12687 and then Has_Interfaces (Tagged_Type));
12689 -- Step 1: Transfer to the full-view primitives associated with the
12690 -- partial-view that cover interface primitives. Conceptually this
12691 -- work should be done later by Process_Full_View; done here to
12692 -- simplify its implementation at later stages. It can be safely
12693 -- done here because interfaces must be visible in the partial and
12694 -- private view (RM 7.3(7.3/2)).
12696 -- Small optimization: This work is only required if the parent is
12697 -- abstract. If the tagged type is not abstract, it cannot have
12698 -- abstract primitives (the only entities in the list of primitives of
12699 -- non-abstract tagged types that can reference abstract primitives
12700 -- through its Alias attribute are the internal entities that have
12701 -- attribute Interface_Alias, and these entities are generated later
12702 -- by Add_Internal_Interface_Entities).
12704 if In_Private_Part (Current_Scope)
12705 and then Is_Abstract_Type (Parent_Type)
12707 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12708 while Present (Elmt) loop
12709 Subp := Node (Elmt);
12711 -- At this stage it is not possible to have entities in the list
12712 -- of primitives that have attribute Interface_Alias
12714 pragma Assert (No (Interface_Alias (Subp)));
12716 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12718 if Is_Interface (Typ) then
12719 E := Find_Primitive_Covering_Interface
12720 (Tagged_Type => Tagged_Type,
12721 Iface_Prim => Subp);
12724 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12726 Replace_Elmt (Elmt, E);
12727 Remove_Homonym (Subp);
12735 -- Step 2: Add primitives of progenitors that are not implemented by
12736 -- parents of Tagged_Type
12738 if Present (Interfaces (Base_Type (Tagged_Type))) then
12739 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12740 while Present (Iface_Elmt) loop
12741 Iface := Node (Iface_Elmt);
12743 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12744 while Present (Prim_Elmt) loop
12745 Iface_Subp := Node (Prim_Elmt);
12747 -- Exclude derivation of predefined primitives except those
12748 -- that come from source. Required to catch declarations of
12749 -- equality operators of interfaces. For example:
12751 -- type Iface is interface;
12752 -- function "=" (Left, Right : Iface) return Boolean;
12754 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12755 or else Comes_From_Source (Iface_Subp)
12757 E := Find_Primitive_Covering_Interface
12758 (Tagged_Type => Tagged_Type,
12759 Iface_Prim => Iface_Subp);
12761 -- If not found we derive a new primitive leaving its alias
12762 -- attribute referencing the interface primitive
12766 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12768 -- Ada 2012 (AI05-0197): If the covering primitive's name
12769 -- differs from the name of the interface primitive then it
12770 -- is a private primitive inherited from a parent type. In
12771 -- such case, given that Tagged_Type covers the interface,
12772 -- the inherited private primitive becomes visible. For such
12773 -- purpose we add a new entity that renames the inherited
12774 -- private primitive.
12776 elsif Chars (E) /= Chars (Iface_Subp) then
12777 pragma Assert (Has_Suffix (E, 'P'));
12779 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12780 Set_Alias (New_Subp, E);
12781 Set_Is_Abstract_Subprogram (New_Subp,
12782 Is_Abstract_Subprogram (E));
12784 -- Propagate to the full view interface entities associated
12785 -- with the partial view
12787 elsif In_Private_Part (Current_Scope)
12788 and then Present (Alias (E))
12789 and then Alias (E) = Iface_Subp
12791 List_Containing (Parent (E)) /=
12792 Private_Declarations
12794 (Unit_Declaration_Node (Current_Scope)))
12796 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12800 Next_Elmt (Prim_Elmt);
12803 Next_Elmt (Iface_Elmt);
12806 end Derive_Progenitor_Subprograms;
12808 -----------------------
12809 -- Derive_Subprogram --
12810 -----------------------
12812 procedure Derive_Subprogram
12813 (New_Subp : in out Entity_Id;
12814 Parent_Subp : Entity_Id;
12815 Derived_Type : Entity_Id;
12816 Parent_Type : Entity_Id;
12817 Actual_Subp : Entity_Id := Empty)
12819 Formal : Entity_Id;
12820 -- Formal parameter of parent primitive operation
12822 Formal_Of_Actual : Entity_Id;
12823 -- Formal parameter of actual operation, when the derivation is to
12824 -- create a renaming for a primitive operation of an actual in an
12827 New_Formal : Entity_Id;
12828 -- Formal of inherited operation
12830 Visible_Subp : Entity_Id := Parent_Subp;
12832 function Is_Private_Overriding return Boolean;
12833 -- If Subp is a private overriding of a visible operation, the inherited
12834 -- operation derives from the overridden op (even though its body is the
12835 -- overriding one) and the inherited operation is visible now. See
12836 -- sem_disp to see the full details of the handling of the overridden
12837 -- subprogram, which is removed from the list of primitive operations of
12838 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12839 -- and used to diagnose abstract operations that need overriding in the
12842 procedure Replace_Type (Id, New_Id : Entity_Id);
12843 -- When the type is an anonymous access type, create a new access type
12844 -- designating the derived type.
12846 procedure Set_Derived_Name;
12847 -- This procedure sets the appropriate Chars name for New_Subp. This
12848 -- is normally just a copy of the parent name. An exception arises for
12849 -- type support subprograms, where the name is changed to reflect the
12850 -- name of the derived type, e.g. if type foo is derived from type bar,
12851 -- then a procedure barDA is derived with a name fooDA.
12853 ---------------------------
12854 -- Is_Private_Overriding --
12855 ---------------------------
12857 function Is_Private_Overriding return Boolean is
12861 -- If the parent is not a dispatching operation there is no
12862 -- need to investigate overridings
12864 if not Is_Dispatching_Operation (Parent_Subp) then
12868 -- The visible operation that is overridden is a homonym of the
12869 -- parent subprogram. We scan the homonym chain to find the one
12870 -- whose alias is the subprogram we are deriving.
12872 Prev := Current_Entity (Parent_Subp);
12873 while Present (Prev) loop
12874 if Ekind (Prev) = Ekind (Parent_Subp)
12875 and then Alias (Prev) = Parent_Subp
12876 and then Scope (Parent_Subp) = Scope (Prev)
12877 and then not Is_Hidden (Prev)
12879 Visible_Subp := Prev;
12883 Prev := Homonym (Prev);
12887 end Is_Private_Overriding;
12893 procedure Replace_Type (Id, New_Id : Entity_Id) is
12894 Acc_Type : Entity_Id;
12895 Par : constant Node_Id := Parent (Derived_Type);
12898 -- When the type is an anonymous access type, create a new access
12899 -- type designating the derived type. This itype must be elaborated
12900 -- at the point of the derivation, not on subsequent calls that may
12901 -- be out of the proper scope for Gigi, so we insert a reference to
12902 -- it after the derivation.
12904 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12906 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12909 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12910 and then Present (Full_View (Desig_Typ))
12911 and then not Is_Private_Type (Parent_Type)
12913 Desig_Typ := Full_View (Desig_Typ);
12916 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12918 -- Ada 2005 (AI-251): Handle also derivations of abstract
12919 -- interface primitives.
12921 or else (Is_Interface (Desig_Typ)
12922 and then not Is_Class_Wide_Type (Desig_Typ))
12924 Acc_Type := New_Copy (Etype (Id));
12925 Set_Etype (Acc_Type, Acc_Type);
12926 Set_Scope (Acc_Type, New_Subp);
12928 -- Compute size of anonymous access type
12930 if Is_Array_Type (Desig_Typ)
12931 and then not Is_Constrained (Desig_Typ)
12933 Init_Size (Acc_Type, 2 * System_Address_Size);
12935 Init_Size (Acc_Type, System_Address_Size);
12938 Init_Alignment (Acc_Type);
12939 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12941 Set_Etype (New_Id, Acc_Type);
12942 Set_Scope (New_Id, New_Subp);
12944 -- Create a reference to it
12945 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12948 Set_Etype (New_Id, Etype (Id));
12952 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12954 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12955 and then Present (Full_View (Etype (Id)))
12957 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12959 -- Constraint checks on formals are generated during expansion,
12960 -- based on the signature of the original subprogram. The bounds
12961 -- of the derived type are not relevant, and thus we can use
12962 -- the base type for the formals. However, the return type may be
12963 -- used in a context that requires that the proper static bounds
12964 -- be used (a case statement, for example) and for those cases
12965 -- we must use the derived type (first subtype), not its base.
12967 -- If the derived_type_definition has no constraints, we know that
12968 -- the derived type has the same constraints as the first subtype
12969 -- of the parent, and we can also use it rather than its base,
12970 -- which can lead to more efficient code.
12972 if Etype (Id) = Parent_Type then
12973 if Is_Scalar_Type (Parent_Type)
12975 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12977 Set_Etype (New_Id, Derived_Type);
12979 elsif Nkind (Par) = N_Full_Type_Declaration
12981 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12984 (Subtype_Indication (Type_Definition (Par)))
12986 Set_Etype (New_Id, Derived_Type);
12989 Set_Etype (New_Id, Base_Type (Derived_Type));
12993 Set_Etype (New_Id, Base_Type (Derived_Type));
12997 Set_Etype (New_Id, Etype (Id));
13001 ----------------------
13002 -- Set_Derived_Name --
13003 ----------------------
13005 procedure Set_Derived_Name is
13006 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13008 if Nm = TSS_Null then
13009 Set_Chars (New_Subp, Chars (Parent_Subp));
13011 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13013 end Set_Derived_Name;
13015 -- Start of processing for Derive_Subprogram
13019 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13020 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13022 -- Check whether the inherited subprogram is a private operation that
13023 -- should be inherited but not yet made visible. Such subprograms can
13024 -- become visible at a later point (e.g., the private part of a public
13025 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13026 -- following predicate is true, then this is not such a private
13027 -- operation and the subprogram simply inherits the name of the parent
13028 -- subprogram. Note the special check for the names of controlled
13029 -- operations, which are currently exempted from being inherited with
13030 -- a hidden name because they must be findable for generation of
13031 -- implicit run-time calls.
13033 if not Is_Hidden (Parent_Subp)
13034 or else Is_Internal (Parent_Subp)
13035 or else Is_Private_Overriding
13036 or else Is_Internal_Name (Chars (Parent_Subp))
13037 or else Chars (Parent_Subp) = Name_Initialize
13038 or else Chars (Parent_Subp) = Name_Adjust
13039 or else Chars (Parent_Subp) = Name_Finalize
13043 -- An inherited dispatching equality will be overridden by an internally
13044 -- generated one, or by an explicit one, so preserve its name and thus
13045 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13046 -- private operation it may become invisible if the full view has
13047 -- progenitors, and the dispatch table will be malformed.
13048 -- We check that the type is limited to handle the anomalous declaration
13049 -- of Limited_Controlled, which is derived from a non-limited type, and
13050 -- which is handled specially elsewhere as well.
13052 elsif Chars (Parent_Subp) = Name_Op_Eq
13053 and then Is_Dispatching_Operation (Parent_Subp)
13054 and then Etype (Parent_Subp) = Standard_Boolean
13055 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13057 Etype (First_Formal (Parent_Subp)) =
13058 Etype (Next_Formal (First_Formal (Parent_Subp)))
13062 -- If parent is hidden, this can be a regular derivation if the
13063 -- parent is immediately visible in a non-instantiating context,
13064 -- or if we are in the private part of an instance. This test
13065 -- should still be refined ???
13067 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13068 -- operation as a non-visible operation in cases where the parent
13069 -- subprogram might not be visible now, but was visible within the
13070 -- original generic, so it would be wrong to make the inherited
13071 -- subprogram non-visible now. (Not clear if this test is fully
13072 -- correct; are there any cases where we should declare the inherited
13073 -- operation as not visible to avoid it being overridden, e.g., when
13074 -- the parent type is a generic actual with private primitives ???)
13076 -- (they should be treated the same as other private inherited
13077 -- subprograms, but it's not clear how to do this cleanly). ???
13079 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13080 and then Is_Immediately_Visible (Parent_Subp)
13081 and then not In_Instance)
13082 or else In_Instance_Not_Visible
13086 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13087 -- overrides an interface primitive because interface primitives
13088 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13090 elsif Ada_Version >= Ada_2005
13091 and then Is_Dispatching_Operation (Parent_Subp)
13092 and then Covers_Some_Interface (Parent_Subp)
13096 -- Otherwise, the type is inheriting a private operation, so enter
13097 -- it with a special name so it can't be overridden.
13100 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13103 Set_Parent (New_Subp, Parent (Derived_Type));
13105 if Present (Actual_Subp) then
13106 Replace_Type (Actual_Subp, New_Subp);
13108 Replace_Type (Parent_Subp, New_Subp);
13111 Conditional_Delay (New_Subp, Parent_Subp);
13113 -- If we are creating a renaming for a primitive operation of an
13114 -- actual of a generic derived type, we must examine the signature
13115 -- of the actual primitive, not that of the generic formal, which for
13116 -- example may be an interface. However the name and initial value
13117 -- of the inherited operation are those of the formal primitive.
13119 Formal := First_Formal (Parent_Subp);
13121 if Present (Actual_Subp) then
13122 Formal_Of_Actual := First_Formal (Actual_Subp);
13124 Formal_Of_Actual := Empty;
13127 while Present (Formal) loop
13128 New_Formal := New_Copy (Formal);
13130 -- Normally we do not go copying parents, but in the case of
13131 -- formals, we need to link up to the declaration (which is the
13132 -- parameter specification), and it is fine to link up to the
13133 -- original formal's parameter specification in this case.
13135 Set_Parent (New_Formal, Parent (Formal));
13136 Append_Entity (New_Formal, New_Subp);
13138 if Present (Formal_Of_Actual) then
13139 Replace_Type (Formal_Of_Actual, New_Formal);
13140 Next_Formal (Formal_Of_Actual);
13142 Replace_Type (Formal, New_Formal);
13145 Next_Formal (Formal);
13148 -- If this derivation corresponds to a tagged generic actual, then
13149 -- primitive operations rename those of the actual. Otherwise the
13150 -- primitive operations rename those of the parent type, If the parent
13151 -- renames an intrinsic operator, so does the new subprogram. We except
13152 -- concatenation, which is always properly typed, and does not get
13153 -- expanded as other intrinsic operations.
13155 if No (Actual_Subp) then
13156 if Is_Intrinsic_Subprogram (Parent_Subp) then
13157 Set_Is_Intrinsic_Subprogram (New_Subp);
13159 if Present (Alias (Parent_Subp))
13160 and then Chars (Parent_Subp) /= Name_Op_Concat
13162 Set_Alias (New_Subp, Alias (Parent_Subp));
13164 Set_Alias (New_Subp, Parent_Subp);
13168 Set_Alias (New_Subp, Parent_Subp);
13172 Set_Alias (New_Subp, Actual_Subp);
13175 -- Derived subprograms of a tagged type must inherit the convention
13176 -- of the parent subprogram (a requirement of AI-117). Derived
13177 -- subprograms of untagged types simply get convention Ada by default.
13179 if Is_Tagged_Type (Derived_Type) then
13180 Set_Convention (New_Subp, Convention (Parent_Subp));
13183 -- Predefined controlled operations retain their name even if the parent
13184 -- is hidden (see above), but they are not primitive operations if the
13185 -- ancestor is not visible, for example if the parent is a private
13186 -- extension completed with a controlled extension. Note that a full
13187 -- type that is controlled can break privacy: the flag Is_Controlled is
13188 -- set on both views of the type.
13190 if Is_Controlled (Parent_Type)
13192 (Chars (Parent_Subp) = Name_Initialize
13193 or else Chars (Parent_Subp) = Name_Adjust
13194 or else Chars (Parent_Subp) = Name_Finalize)
13195 and then Is_Hidden (Parent_Subp)
13196 and then not Is_Visibly_Controlled (Parent_Type)
13198 Set_Is_Hidden (New_Subp);
13201 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13202 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13204 if Ekind (Parent_Subp) = E_Procedure then
13205 Set_Is_Valued_Procedure
13206 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13208 Set_Has_Controlling_Result
13209 (New_Subp, Has_Controlling_Result (Parent_Subp));
13212 -- No_Return must be inherited properly. If this is overridden in the
13213 -- case of a dispatching operation, then a check is made in Sem_Disp
13214 -- that the overriding operation is also No_Return (no such check is
13215 -- required for the case of non-dispatching operation.
13217 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13219 -- A derived function with a controlling result is abstract. If the
13220 -- Derived_Type is a nonabstract formal generic derived type, then
13221 -- inherited operations are not abstract: the required check is done at
13222 -- instantiation time. If the derivation is for a generic actual, the
13223 -- function is not abstract unless the actual is.
13225 if Is_Generic_Type (Derived_Type)
13226 and then not Is_Abstract_Type (Derived_Type)
13230 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13231 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13233 elsif Ada_Version >= Ada_2005
13234 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13235 or else (Is_Tagged_Type (Derived_Type)
13236 and then Etype (New_Subp) = Derived_Type
13237 and then not Is_Null_Extension (Derived_Type))
13238 or else (Is_Tagged_Type (Derived_Type)
13239 and then Ekind (Etype (New_Subp)) =
13240 E_Anonymous_Access_Type
13241 and then Designated_Type (Etype (New_Subp)) =
13243 and then not Is_Null_Extension (Derived_Type)))
13244 and then No (Actual_Subp)
13246 if not Is_Tagged_Type (Derived_Type)
13247 or else Is_Abstract_Type (Derived_Type)
13248 or else Is_Abstract_Subprogram (Alias (New_Subp))
13250 Set_Is_Abstract_Subprogram (New_Subp);
13252 Set_Requires_Overriding (New_Subp);
13255 elsif Ada_Version < Ada_2005
13256 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13257 or else (Is_Tagged_Type (Derived_Type)
13258 and then Etype (New_Subp) = Derived_Type
13259 and then No (Actual_Subp)))
13261 Set_Is_Abstract_Subprogram (New_Subp);
13263 -- AI05-0097 : an inherited operation that dispatches on result is
13264 -- abstract if the derived type is abstract, even if the parent type
13265 -- is concrete and the derived type is a null extension.
13267 elsif Has_Controlling_Result (Alias (New_Subp))
13268 and then Is_Abstract_Type (Etype (New_Subp))
13270 Set_Is_Abstract_Subprogram (New_Subp);
13272 -- Finally, if the parent type is abstract we must verify that all
13273 -- inherited operations are either non-abstract or overridden, or that
13274 -- the derived type itself is abstract (this check is performed at the
13275 -- end of a package declaration, in Check_Abstract_Overriding). A
13276 -- private overriding in the parent type will not be visible in the
13277 -- derivation if we are not in an inner package or in a child unit of
13278 -- the parent type, in which case the abstractness of the inherited
13279 -- operation is carried to the new subprogram.
13281 elsif Is_Abstract_Type (Parent_Type)
13282 and then not In_Open_Scopes (Scope (Parent_Type))
13283 and then Is_Private_Overriding
13284 and then Is_Abstract_Subprogram (Visible_Subp)
13286 if No (Actual_Subp) then
13287 Set_Alias (New_Subp, Visible_Subp);
13288 Set_Is_Abstract_Subprogram (New_Subp, True);
13291 -- If this is a derivation for an instance of a formal derived
13292 -- type, abstractness comes from the primitive operation of the
13293 -- actual, not from the operation inherited from the ancestor.
13295 Set_Is_Abstract_Subprogram
13296 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13300 New_Overloaded_Entity (New_Subp, Derived_Type);
13302 -- Check for case of a derived subprogram for the instantiation of a
13303 -- formal derived tagged type, if so mark the subprogram as dispatching
13304 -- and inherit the dispatching attributes of the parent subprogram. The
13305 -- derived subprogram is effectively renaming of the actual subprogram,
13306 -- so it needs to have the same attributes as the actual.
13308 if Present (Actual_Subp)
13309 and then Is_Dispatching_Operation (Parent_Subp)
13311 Set_Is_Dispatching_Operation (New_Subp);
13313 if Present (DTC_Entity (Parent_Subp)) then
13314 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
13315 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
13319 -- Indicate that a derived subprogram does not require a body and that
13320 -- it does not require processing of default expressions.
13322 Set_Has_Completion (New_Subp);
13323 Set_Default_Expressions_Processed (New_Subp);
13325 if Ekind (New_Subp) = E_Function then
13326 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13328 end Derive_Subprogram;
13330 ------------------------
13331 -- Derive_Subprograms --
13332 ------------------------
13334 procedure Derive_Subprograms
13335 (Parent_Type : Entity_Id;
13336 Derived_Type : Entity_Id;
13337 Generic_Actual : Entity_Id := Empty)
13339 Op_List : constant Elist_Id :=
13340 Collect_Primitive_Operations (Parent_Type);
13342 function Check_Derived_Type return Boolean;
13343 -- Check that all the entities derived from Parent_Type are found in
13344 -- the list of primitives of Derived_Type exactly in the same order.
13346 procedure Derive_Interface_Subprogram
13347 (New_Subp : in out Entity_Id;
13349 Actual_Subp : Entity_Id);
13350 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13351 -- (which is an interface primitive). If Generic_Actual is present then
13352 -- Actual_Subp is the actual subprogram corresponding with the generic
13353 -- subprogram Subp.
13355 function Check_Derived_Type return Boolean is
13359 New_Subp : Entity_Id;
13364 -- Traverse list of entities in the current scope searching for
13365 -- an incomplete type whose full-view is derived type
13367 E := First_Entity (Scope (Derived_Type));
13369 and then E /= Derived_Type
13371 if Ekind (E) = E_Incomplete_Type
13372 and then Present (Full_View (E))
13373 and then Full_View (E) = Derived_Type
13375 -- Disable this test if Derived_Type completes an incomplete
13376 -- type because in such case more primitives can be added
13377 -- later to the list of primitives of Derived_Type by routine
13378 -- Process_Incomplete_Dependents
13383 E := Next_Entity (E);
13386 List := Collect_Primitive_Operations (Derived_Type);
13387 Elmt := First_Elmt (List);
13389 Op_Elmt := First_Elmt (Op_List);
13390 while Present (Op_Elmt) loop
13391 Subp := Node (Op_Elmt);
13392 New_Subp := Node (Elmt);
13394 -- At this early stage Derived_Type has no entities with attribute
13395 -- Interface_Alias. In addition, such primitives are always
13396 -- located at the end of the list of primitives of Parent_Type.
13397 -- Therefore, if found we can safely stop processing pending
13400 exit when Present (Interface_Alias (Subp));
13402 -- Handle hidden entities
13404 if not Is_Predefined_Dispatching_Operation (Subp)
13405 and then Is_Hidden (Subp)
13407 if Present (New_Subp)
13408 and then Primitive_Names_Match (Subp, New_Subp)
13414 if not Present (New_Subp)
13415 or else Ekind (Subp) /= Ekind (New_Subp)
13416 or else not Primitive_Names_Match (Subp, New_Subp)
13424 Next_Elmt (Op_Elmt);
13428 end Check_Derived_Type;
13430 ---------------------------------
13431 -- Derive_Interface_Subprogram --
13432 ---------------------------------
13434 procedure Derive_Interface_Subprogram
13435 (New_Subp : in out Entity_Id;
13437 Actual_Subp : Entity_Id)
13439 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13440 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13443 pragma Assert (Is_Interface (Iface_Type));
13446 (New_Subp => New_Subp,
13447 Parent_Subp => Iface_Subp,
13448 Derived_Type => Derived_Type,
13449 Parent_Type => Iface_Type,
13450 Actual_Subp => Actual_Subp);
13452 -- Given that this new interface entity corresponds with a primitive
13453 -- of the parent that was not overridden we must leave it associated
13454 -- with its parent primitive to ensure that it will share the same
13455 -- dispatch table slot when overridden.
13457 if No (Actual_Subp) then
13458 Set_Alias (New_Subp, Subp);
13460 -- For instantiations this is not needed since the previous call to
13461 -- Derive_Subprogram leaves the entity well decorated.
13464 pragma Assert (Alias (New_Subp) = Actual_Subp);
13467 end Derive_Interface_Subprogram;
13471 Alias_Subp : Entity_Id;
13472 Act_List : Elist_Id;
13473 Act_Elmt : Elmt_Id := No_Elmt;
13474 Act_Subp : Entity_Id := Empty;
13476 Need_Search : Boolean := False;
13477 New_Subp : Entity_Id := Empty;
13478 Parent_Base : Entity_Id;
13481 -- Start of processing for Derive_Subprograms
13484 if Ekind (Parent_Type) = E_Record_Type_With_Private
13485 and then Has_Discriminants (Parent_Type)
13486 and then Present (Full_View (Parent_Type))
13488 Parent_Base := Full_View (Parent_Type);
13490 Parent_Base := Parent_Type;
13493 if Present (Generic_Actual) then
13494 Act_List := Collect_Primitive_Operations (Generic_Actual);
13495 Act_Elmt := First_Elmt (Act_List);
13498 -- Derive primitives inherited from the parent. Note that if the generic
13499 -- actual is present, this is not really a type derivation, it is a
13500 -- completion within an instance.
13502 -- Case 1: Derived_Type does not implement interfaces
13504 if not Is_Tagged_Type (Derived_Type)
13505 or else (not Has_Interfaces (Derived_Type)
13506 and then not (Present (Generic_Actual)
13508 Has_Interfaces (Generic_Actual)))
13510 Elmt := First_Elmt (Op_List);
13511 while Present (Elmt) loop
13512 Subp := Node (Elmt);
13514 -- Literals are derived earlier in the process of building the
13515 -- derived type, and are skipped here.
13517 if Ekind (Subp) = E_Enumeration_Literal then
13520 -- The actual is a direct descendant and the common primitive
13521 -- operations appear in the same order.
13523 -- If the generic parent type is present, the derived type is an
13524 -- instance of a formal derived type, and within the instance its
13525 -- operations are those of the actual. We derive from the formal
13526 -- type but make the inherited operations aliases of the
13527 -- corresponding operations of the actual.
13530 pragma Assert (No (Node (Act_Elmt))
13531 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13533 Type_Conformant (Subp, Node (Act_Elmt),
13534 Skip_Controlling_Formals => True)));
13537 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13539 if Present (Act_Elmt) then
13540 Next_Elmt (Act_Elmt);
13547 -- Case 2: Derived_Type implements interfaces
13550 -- If the parent type has no predefined primitives we remove
13551 -- predefined primitives from the list of primitives of generic
13552 -- actual to simplify the complexity of this algorithm.
13554 if Present (Generic_Actual) then
13556 Has_Predefined_Primitives : Boolean := False;
13559 -- Check if the parent type has predefined primitives
13561 Elmt := First_Elmt (Op_List);
13562 while Present (Elmt) loop
13563 Subp := Node (Elmt);
13565 if Is_Predefined_Dispatching_Operation (Subp)
13566 and then not Comes_From_Source (Ultimate_Alias (Subp))
13568 Has_Predefined_Primitives := True;
13575 -- Remove predefined primitives of Generic_Actual. We must use
13576 -- an auxiliary list because in case of tagged types the value
13577 -- returned by Collect_Primitive_Operations is the value stored
13578 -- in its Primitive_Operations attribute (and we don't want to
13579 -- modify its current contents).
13581 if not Has_Predefined_Primitives then
13583 Aux_List : constant Elist_Id := New_Elmt_List;
13586 Elmt := First_Elmt (Act_List);
13587 while Present (Elmt) loop
13588 Subp := Node (Elmt);
13590 if not Is_Predefined_Dispatching_Operation (Subp)
13591 or else Comes_From_Source (Subp)
13593 Append_Elmt (Subp, Aux_List);
13599 Act_List := Aux_List;
13603 Act_Elmt := First_Elmt (Act_List);
13604 Act_Subp := Node (Act_Elmt);
13608 -- Stage 1: If the generic actual is not present we derive the
13609 -- primitives inherited from the parent type. If the generic parent
13610 -- type is present, the derived type is an instance of a formal
13611 -- derived type, and within the instance its operations are those of
13612 -- the actual. We derive from the formal type but make the inherited
13613 -- operations aliases of the corresponding operations of the actual.
13615 Elmt := First_Elmt (Op_List);
13616 while Present (Elmt) loop
13617 Subp := Node (Elmt);
13618 Alias_Subp := Ultimate_Alias (Subp);
13620 -- Do not derive internal entities of the parent that link
13621 -- interface primitives with their covering primitive. These
13622 -- entities will be added to this type when frozen.
13624 if Present (Interface_Alias (Subp)) then
13628 -- If the generic actual is present find the corresponding
13629 -- operation in the generic actual. If the parent type is a
13630 -- direct ancestor of the derived type then, even if it is an
13631 -- interface, the operations are inherited from the primary
13632 -- dispatch table and are in the proper order. If we detect here
13633 -- that primitives are not in the same order we traverse the list
13634 -- of primitive operations of the actual to find the one that
13635 -- implements the interface primitive.
13639 (Present (Generic_Actual)
13640 and then Present (Act_Subp)
13642 (Primitive_Names_Match (Subp, Act_Subp)
13644 Type_Conformant (Subp, Act_Subp,
13645 Skip_Controlling_Formals => True)))
13647 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
13649 -- Remember that we need searching for all pending primitives
13651 Need_Search := True;
13653 -- Handle entities associated with interface primitives
13655 if Present (Alias_Subp)
13656 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13657 and then not Is_Predefined_Dispatching_Operation (Subp)
13659 -- Search for the primitive in the homonym chain
13662 Find_Primitive_Covering_Interface
13663 (Tagged_Type => Generic_Actual,
13664 Iface_Prim => Alias_Subp);
13666 -- Previous search may not locate primitives covering
13667 -- interfaces defined in generics units or instantiations.
13668 -- (it fails if the covering primitive has formals whose
13669 -- type is also defined in generics or instantiations).
13670 -- In such case we search in the list of primitives of the
13671 -- generic actual for the internal entity that links the
13672 -- interface primitive and the covering primitive.
13675 and then Is_Generic_Type (Parent_Type)
13677 -- This code has been designed to handle only generic
13678 -- formals that implement interfaces that are defined
13679 -- in a generic unit or instantiation. If this code is
13680 -- needed for other cases we must review it because
13681 -- (given that it relies on Original_Location to locate
13682 -- the primitive of Generic_Actual that covers the
13683 -- interface) it could leave linked through attribute
13684 -- Alias entities of unrelated instantiations).
13688 (Scope (Find_Dispatching_Type (Alias_Subp)))
13690 Instantiation_Depth
13691 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13694 Iface_Prim_Loc : constant Source_Ptr :=
13695 Original_Location (Sloc (Alias_Subp));
13700 First_Elmt (Primitive_Operations (Generic_Actual));
13702 Search : while Present (Elmt) loop
13703 Prim := Node (Elmt);
13705 if Present (Interface_Alias (Prim))
13706 and then Original_Location
13707 (Sloc (Interface_Alias (Prim)))
13710 Act_Subp := Alias (Prim);
13719 pragma Assert (Present (Act_Subp)
13720 or else Is_Abstract_Type (Generic_Actual)
13721 or else Serious_Errors_Detected > 0);
13723 -- Handle predefined primitives plus the rest of user-defined
13727 Act_Elmt := First_Elmt (Act_List);
13728 while Present (Act_Elmt) loop
13729 Act_Subp := Node (Act_Elmt);
13731 exit when Primitive_Names_Match (Subp, Act_Subp)
13732 and then Type_Conformant
13734 Skip_Controlling_Formals => True)
13735 and then No (Interface_Alias (Act_Subp));
13737 Next_Elmt (Act_Elmt);
13740 if No (Act_Elmt) then
13746 -- Case 1: If the parent is a limited interface then it has the
13747 -- predefined primitives of synchronized interfaces. However, the
13748 -- actual type may be a non-limited type and hence it does not
13749 -- have such primitives.
13751 if Present (Generic_Actual)
13752 and then not Present (Act_Subp)
13753 and then Is_Limited_Interface (Parent_Base)
13754 and then Is_Predefined_Interface_Primitive (Subp)
13758 -- Case 2: Inherit entities associated with interfaces that were
13759 -- not covered by the parent type. We exclude here null interface
13760 -- primitives because they do not need special management.
13762 -- We also exclude interface operations that are renamings. If the
13763 -- subprogram is an explicit renaming of an interface primitive,
13764 -- it is a regular primitive operation, and the presence of its
13765 -- alias is not relevant: it has to be derived like any other
13768 elsif Present (Alias (Subp))
13769 and then Nkind (Unit_Declaration_Node (Subp)) /=
13770 N_Subprogram_Renaming_Declaration
13771 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13773 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13774 and then Null_Present (Parent (Alias_Subp)))
13776 -- If this is an abstract private type then we transfer the
13777 -- derivation of the interface primitive from the partial view
13778 -- to the full view. This is safe because all the interfaces
13779 -- must be visible in the partial view. Done to avoid adding
13780 -- a new interface derivation to the private part of the
13781 -- enclosing package; otherwise this new derivation would be
13782 -- decorated as hidden when the analysis of the enclosing
13783 -- package completes.
13785 if Is_Abstract_Type (Derived_Type)
13786 and then In_Private_Part (Current_Scope)
13787 and then Has_Private_Declaration (Derived_Type)
13790 Partial_View : Entity_Id;
13795 Partial_View := First_Entity (Current_Scope);
13797 exit when No (Partial_View)
13798 or else (Has_Private_Declaration (Partial_View)
13800 Full_View (Partial_View) = Derived_Type);
13802 Next_Entity (Partial_View);
13805 -- If the partial view was not found then the source code
13806 -- has errors and the derivation is not needed.
13808 if Present (Partial_View) then
13810 First_Elmt (Primitive_Operations (Partial_View));
13811 while Present (Elmt) loop
13812 Ent := Node (Elmt);
13814 if Present (Alias (Ent))
13815 and then Ultimate_Alias (Ent) = Alias (Subp)
13818 (Ent, Primitive_Operations (Derived_Type));
13825 -- If the interface primitive was not found in the
13826 -- partial view then this interface primitive was
13827 -- overridden. We add a derivation to activate in
13828 -- Derive_Progenitor_Subprograms the machinery to
13832 Derive_Interface_Subprogram
13833 (New_Subp => New_Subp,
13835 Actual_Subp => Act_Subp);
13840 Derive_Interface_Subprogram
13841 (New_Subp => New_Subp,
13843 Actual_Subp => Act_Subp);
13846 -- Case 3: Common derivation
13850 (New_Subp => New_Subp,
13851 Parent_Subp => Subp,
13852 Derived_Type => Derived_Type,
13853 Parent_Type => Parent_Base,
13854 Actual_Subp => Act_Subp);
13857 -- No need to update Act_Elm if we must search for the
13858 -- corresponding operation in the generic actual
13861 and then Present (Act_Elmt)
13863 Next_Elmt (Act_Elmt);
13864 Act_Subp := Node (Act_Elmt);
13871 -- Inherit additional operations from progenitors. If the derived
13872 -- type is a generic actual, there are not new primitive operations
13873 -- for the type because it has those of the actual, and therefore
13874 -- nothing needs to be done. The renamings generated above are not
13875 -- primitive operations, and their purpose is simply to make the
13876 -- proper operations visible within an instantiation.
13878 if No (Generic_Actual) then
13879 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13883 -- Final check: Direct descendants must have their primitives in the
13884 -- same order. We exclude from this test untagged types and instances
13885 -- of formal derived types. We skip this test if we have already
13886 -- reported serious errors in the sources.
13888 pragma Assert (not Is_Tagged_Type (Derived_Type)
13889 or else Present (Generic_Actual)
13890 or else Serious_Errors_Detected > 0
13891 or else Check_Derived_Type);
13892 end Derive_Subprograms;
13894 --------------------------------
13895 -- Derived_Standard_Character --
13896 --------------------------------
13898 procedure Derived_Standard_Character
13900 Parent_Type : Entity_Id;
13901 Derived_Type : Entity_Id)
13903 Loc : constant Source_Ptr := Sloc (N);
13904 Def : constant Node_Id := Type_Definition (N);
13905 Indic : constant Node_Id := Subtype_Indication (Def);
13906 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13907 Implicit_Base : constant Entity_Id :=
13909 (E_Enumeration_Type, N, Derived_Type, 'B');
13915 Discard_Node (Process_Subtype (Indic, N));
13917 Set_Etype (Implicit_Base, Parent_Base);
13918 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
13919 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
13921 Set_Is_Character_Type (Implicit_Base, True);
13922 Set_Has_Delayed_Freeze (Implicit_Base);
13924 -- The bounds of the implicit base are the bounds of the parent base.
13925 -- Note that their type is the parent base.
13927 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13928 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13930 Set_Scalar_Range (Implicit_Base,
13933 High_Bound => Hi));
13935 Conditional_Delay (Derived_Type, Parent_Type);
13937 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13938 Set_Etype (Derived_Type, Implicit_Base);
13939 Set_Size_Info (Derived_Type, Parent_Type);
13941 if Unknown_RM_Size (Derived_Type) then
13942 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13945 Set_Is_Character_Type (Derived_Type, True);
13947 if Nkind (Indic) /= N_Subtype_Indication then
13949 -- If no explicit constraint, the bounds are those
13950 -- of the parent type.
13952 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13953 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13954 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13957 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13959 -- Because the implicit base is used in the conversion of the bounds, we
13960 -- have to freeze it now. This is similar to what is done for numeric
13961 -- types, and it equally suspicious, but otherwise a non-static bound
13962 -- will have a reference to an unfrozen type, which is rejected by Gigi
13963 -- (???). This requires specific care for definition of stream
13964 -- attributes. For details, see comments at the end of
13965 -- Build_Derived_Numeric_Type.
13967 Freeze_Before (N, Implicit_Base);
13968 end Derived_Standard_Character;
13970 ------------------------------
13971 -- Derived_Type_Declaration --
13972 ------------------------------
13974 procedure Derived_Type_Declaration
13977 Is_Completion : Boolean)
13979 Parent_Type : Entity_Id;
13981 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13982 -- Check whether the parent type is a generic formal, or derives
13983 -- directly or indirectly from one.
13985 ------------------------
13986 -- Comes_From_Generic --
13987 ------------------------
13989 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13991 if Is_Generic_Type (Typ) then
13994 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13997 elsif Is_Private_Type (Typ)
13998 and then Present (Full_View (Typ))
13999 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14003 elsif Is_Generic_Actual_Type (Typ) then
14009 end Comes_From_Generic;
14013 Def : constant Node_Id := Type_Definition (N);
14014 Iface_Def : Node_Id;
14015 Indic : constant Node_Id := Subtype_Indication (Def);
14016 Extension : constant Node_Id := Record_Extension_Part (Def);
14017 Parent_Node : Node_Id;
14020 -- Start of processing for Derived_Type_Declaration
14023 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14025 -- Ada 2005 (AI-251): In case of interface derivation check that the
14026 -- parent is also an interface.
14028 if Interface_Present (Def) then
14029 Check_SPARK_Restriction ("interface is not allowed", Def);
14031 if not Is_Interface (Parent_Type) then
14032 Diagnose_Interface (Indic, Parent_Type);
14035 Parent_Node := Parent (Base_Type (Parent_Type));
14036 Iface_Def := Type_Definition (Parent_Node);
14038 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14039 -- other limited interfaces.
14041 if Limited_Present (Def) then
14042 if Limited_Present (Iface_Def) then
14045 elsif Protected_Present (Iface_Def) then
14047 ("descendant of& must be declared"
14048 & " as a protected interface",
14051 elsif Synchronized_Present (Iface_Def) then
14053 ("descendant of& must be declared"
14054 & " as a synchronized interface",
14057 elsif Task_Present (Iface_Def) then
14059 ("descendant of& must be declared as a task interface",
14064 ("(Ada 2005) limited interface cannot "
14065 & "inherit from non-limited interface", Indic);
14068 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14069 -- from non-limited or limited interfaces.
14071 elsif not Protected_Present (Def)
14072 and then not Synchronized_Present (Def)
14073 and then not Task_Present (Def)
14075 if Limited_Present (Iface_Def) then
14078 elsif Protected_Present (Iface_Def) then
14080 ("descendant of& must be declared"
14081 & " as a protected interface",
14084 elsif Synchronized_Present (Iface_Def) then
14086 ("descendant of& must be declared"
14087 & " as a synchronized interface",
14090 elsif Task_Present (Iface_Def) then
14092 ("descendant of& must be declared as a task interface",
14101 if Is_Tagged_Type (Parent_Type)
14102 and then Is_Concurrent_Type (Parent_Type)
14103 and then not Is_Interface (Parent_Type)
14106 ("parent type of a record extension cannot be "
14107 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14108 Set_Etype (T, Any_Type);
14112 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14115 if Is_Tagged_Type (Parent_Type)
14116 and then Is_Non_Empty_List (Interface_List (Def))
14123 Intf := First (Interface_List (Def));
14124 while Present (Intf) loop
14125 T := Find_Type_Of_Subtype_Indic (Intf);
14127 if not Is_Interface (T) then
14128 Diagnose_Interface (Intf, T);
14130 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14131 -- a limited type from having a nonlimited progenitor.
14133 elsif (Limited_Present (Def)
14134 or else (not Is_Interface (Parent_Type)
14135 and then Is_Limited_Type (Parent_Type)))
14136 and then not Is_Limited_Interface (T)
14139 ("progenitor interface& of limited type must be limited",
14148 if Parent_Type = Any_Type
14149 or else Etype (Parent_Type) = Any_Type
14150 or else (Is_Class_Wide_Type (Parent_Type)
14151 and then Etype (Parent_Type) = T)
14153 -- If Parent_Type is undefined or illegal, make new type into a
14154 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14155 -- errors. If this is a self-definition, emit error now.
14158 or else T = Etype (Parent_Type)
14160 Error_Msg_N ("type cannot be used in its own definition", Indic);
14163 Set_Ekind (T, Ekind (Parent_Type));
14164 Set_Etype (T, Any_Type);
14165 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14167 if Is_Tagged_Type (T)
14168 and then Is_Record_Type (T)
14170 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14176 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14177 -- an interface is special because the list of interfaces in the full
14178 -- view can be given in any order. For example:
14180 -- type A is interface;
14181 -- type B is interface and A;
14182 -- type D is new B with private;
14184 -- type D is new A and B with null record; -- 1 --
14186 -- In this case we perform the following transformation of -1-:
14188 -- type D is new B and A with null record;
14190 -- If the parent of the full-view covers the parent of the partial-view
14191 -- we have two possible cases:
14193 -- 1) They have the same parent
14194 -- 2) The parent of the full-view implements some further interfaces
14196 -- In both cases we do not need to perform the transformation. In the
14197 -- first case the source program is correct and the transformation is
14198 -- not needed; in the second case the source program does not fulfill
14199 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14202 -- This transformation not only simplifies the rest of the analysis of
14203 -- this type declaration but also simplifies the correct generation of
14204 -- the object layout to the expander.
14206 if In_Private_Part (Current_Scope)
14207 and then Is_Interface (Parent_Type)
14211 Partial_View : Entity_Id;
14212 Partial_View_Parent : Entity_Id;
14213 New_Iface : Node_Id;
14216 -- Look for the associated private type declaration
14218 Partial_View := First_Entity (Current_Scope);
14220 exit when No (Partial_View)
14221 or else (Has_Private_Declaration (Partial_View)
14222 and then Full_View (Partial_View) = T);
14224 Next_Entity (Partial_View);
14227 -- If the partial view was not found then the source code has
14228 -- errors and the transformation is not needed.
14230 if Present (Partial_View) then
14231 Partial_View_Parent := Etype (Partial_View);
14233 -- If the parent of the full-view covers the parent of the
14234 -- partial-view we have nothing else to do.
14236 if Interface_Present_In_Ancestor
14237 (Parent_Type, Partial_View_Parent)
14241 -- Traverse the list of interfaces of the full-view to look
14242 -- for the parent of the partial-view and perform the tree
14246 Iface := First (Interface_List (Def));
14247 while Present (Iface) loop
14248 if Etype (Iface) = Etype (Partial_View) then
14249 Rewrite (Subtype_Indication (Def),
14250 New_Copy (Subtype_Indication
14251 (Parent (Partial_View))));
14254 Make_Identifier (Sloc (N), Chars (Parent_Type));
14255 Append (New_Iface, Interface_List (Def));
14257 -- Analyze the transformed code
14259 Derived_Type_Declaration (T, N, Is_Completion);
14270 -- Only composite types other than array types are allowed to have
14271 -- discriminants. In SPARK, no types are allowed to have discriminants.
14273 if Present (Discriminant_Specifications (N)) then
14274 if (Is_Elementary_Type (Parent_Type)
14275 or else Is_Array_Type (Parent_Type))
14276 and then not Error_Posted (N)
14279 ("elementary or array type cannot have discriminants",
14280 Defining_Identifier (First (Discriminant_Specifications (N))));
14281 Set_Has_Discriminants (T, False);
14283 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14287 -- In Ada 83, a derived type defined in a package specification cannot
14288 -- be used for further derivation until the end of its visible part.
14289 -- Note that derivation in the private part of the package is allowed.
14291 if Ada_Version = Ada_83
14292 and then Is_Derived_Type (Parent_Type)
14293 and then In_Visible_Part (Scope (Parent_Type))
14295 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14297 ("(Ada 83): premature use of type for derivation", Indic);
14301 -- Check for early use of incomplete or private type
14303 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14304 Error_Msg_N ("premature derivation of incomplete type", Indic);
14307 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14308 and then not Comes_From_Generic (Parent_Type))
14309 or else Has_Private_Component (Parent_Type)
14311 -- The ancestor type of a formal type can be incomplete, in which
14312 -- case only the operations of the partial view are available in the
14313 -- generic. Subsequent checks may be required when the full view is
14314 -- analyzed to verify that a derivation from a tagged type has an
14317 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14320 elsif No (Underlying_Type (Parent_Type))
14321 or else Has_Private_Component (Parent_Type)
14324 ("premature derivation of derived or private type", Indic);
14326 -- Flag the type itself as being in error, this prevents some
14327 -- nasty problems with subsequent uses of the malformed type.
14329 Set_Error_Posted (T);
14331 -- Check that within the immediate scope of an untagged partial
14332 -- view it's illegal to derive from the partial view if the
14333 -- full view is tagged. (7.3(7))
14335 -- We verify that the Parent_Type is a partial view by checking
14336 -- that it is not a Full_Type_Declaration (i.e. a private type or
14337 -- private extension declaration), to distinguish a partial view
14338 -- from a derivation from a private type which also appears as
14339 -- E_Private_Type. If the parent base type is not declared in an
14340 -- enclosing scope there is no need to check.
14342 elsif Present (Full_View (Parent_Type))
14343 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14344 and then not Is_Tagged_Type (Parent_Type)
14345 and then Is_Tagged_Type (Full_View (Parent_Type))
14346 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14349 ("premature derivation from type with tagged full view",
14354 -- Check that form of derivation is appropriate
14356 Taggd := Is_Tagged_Type (Parent_Type);
14358 -- Perhaps the parent type should be changed to the class-wide type's
14359 -- specific type in this case to prevent cascading errors ???
14361 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14362 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14366 if Present (Extension) and then not Taggd then
14368 ("type derived from untagged type cannot have extension", Indic);
14370 elsif No (Extension) and then Taggd then
14372 -- If this declaration is within a private part (or body) of a
14373 -- generic instantiation then the derivation is allowed (the parent
14374 -- type can only appear tagged in this case if it's a generic actual
14375 -- type, since it would otherwise have been rejected in the analysis
14376 -- of the generic template).
14378 if not Is_Generic_Actual_Type (Parent_Type)
14379 or else In_Visible_Part (Scope (Parent_Type))
14381 if Is_Class_Wide_Type (Parent_Type) then
14383 ("parent type must not be a class-wide type", Indic);
14385 -- Use specific type to prevent cascaded errors.
14387 Parent_Type := Etype (Parent_Type);
14391 ("type derived from tagged type must have extension", Indic);
14396 -- AI-443: Synchronized formal derived types require a private
14397 -- extension. There is no point in checking the ancestor type or
14398 -- the progenitors since the construct is wrong to begin with.
14400 if Ada_Version >= Ada_2005
14401 and then Is_Generic_Type (T)
14402 and then Present (Original_Node (N))
14405 Decl : constant Node_Id := Original_Node (N);
14408 if Nkind (Decl) = N_Formal_Type_Declaration
14409 and then Nkind (Formal_Type_Definition (Decl)) =
14410 N_Formal_Derived_Type_Definition
14411 and then Synchronized_Present (Formal_Type_Definition (Decl))
14412 and then No (Extension)
14414 -- Avoid emitting a duplicate error message
14416 and then not Error_Posted (Indic)
14419 ("synchronized derived type must have extension", N);
14424 if Null_Exclusion_Present (Def)
14425 and then not Is_Access_Type (Parent_Type)
14427 Error_Msg_N ("null exclusion can only apply to an access type", N);
14430 -- Avoid deriving parent primitives of underlying record views
14432 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14433 Derive_Subps => not Is_Underlying_Record_View (T));
14435 -- AI-419: The parent type of an explicitly limited derived type must
14436 -- be a limited type or a limited interface.
14438 if Limited_Present (Def) then
14439 Set_Is_Limited_Record (T);
14441 if Is_Interface (T) then
14442 Set_Is_Limited_Interface (T);
14445 if not Is_Limited_Type (Parent_Type)
14447 (not Is_Interface (Parent_Type)
14448 or else not Is_Limited_Interface (Parent_Type))
14450 -- AI05-0096: a derivation in the private part of an instance is
14451 -- legal if the generic formal is untagged limited, and the actual
14454 if Is_Generic_Actual_Type (Parent_Type)
14455 and then In_Private_Part (Current_Scope)
14458 (Generic_Parent_Type (Parent (Parent_Type)))
14464 ("parent type& of limited type must be limited",
14470 -- In SPARK, there are no derived type definitions other than type
14471 -- extensions of tagged record types.
14473 if No (Extension) then
14474 Check_SPARK_Restriction ("derived type is not allowed", N);
14476 end Derived_Type_Declaration;
14478 ------------------------
14479 -- Diagnose_Interface --
14480 ------------------------
14482 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14484 if not Is_Interface (E)
14485 and then E /= Any_Type
14487 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14489 end Diagnose_Interface;
14491 ----------------------------------
14492 -- Enumeration_Type_Declaration --
14493 ----------------------------------
14495 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14502 -- Create identifier node representing lower bound
14504 B_Node := New_Node (N_Identifier, Sloc (Def));
14505 L := First (Literals (Def));
14506 Set_Chars (B_Node, Chars (L));
14507 Set_Entity (B_Node, L);
14508 Set_Etype (B_Node, T);
14509 Set_Is_Static_Expression (B_Node, True);
14511 R_Node := New_Node (N_Range, Sloc (Def));
14512 Set_Low_Bound (R_Node, B_Node);
14514 Set_Ekind (T, E_Enumeration_Type);
14515 Set_First_Literal (T, L);
14517 Set_Is_Constrained (T);
14521 -- Loop through literals of enumeration type setting pos and rep values
14522 -- except that if the Ekind is already set, then it means the literal
14523 -- was already constructed (case of a derived type declaration and we
14524 -- should not disturb the Pos and Rep values.
14526 while Present (L) loop
14527 if Ekind (L) /= E_Enumeration_Literal then
14528 Set_Ekind (L, E_Enumeration_Literal);
14529 Set_Enumeration_Pos (L, Ev);
14530 Set_Enumeration_Rep (L, Ev);
14531 Set_Is_Known_Valid (L, True);
14535 New_Overloaded_Entity (L);
14536 Generate_Definition (L);
14537 Set_Convention (L, Convention_Intrinsic);
14539 -- Case of character literal
14541 if Nkind (L) = N_Defining_Character_Literal then
14542 Set_Is_Character_Type (T, True);
14544 -- Check violation of No_Wide_Characters
14546 if Restriction_Check_Required (No_Wide_Characters) then
14547 Get_Name_String (Chars (L));
14549 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14550 Check_Restriction (No_Wide_Characters, L);
14559 -- Now create a node representing upper bound
14561 B_Node := New_Node (N_Identifier, Sloc (Def));
14562 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14563 Set_Entity (B_Node, Last (Literals (Def)));
14564 Set_Etype (B_Node, T);
14565 Set_Is_Static_Expression (B_Node, True);
14567 Set_High_Bound (R_Node, B_Node);
14569 -- Initialize various fields of the type. Some of this information
14570 -- may be overwritten later through rep.clauses.
14572 Set_Scalar_Range (T, R_Node);
14573 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14574 Set_Enum_Esize (T);
14575 Set_Enum_Pos_To_Rep (T, Empty);
14577 -- Enumeration type is in ALFA only if it is not a character type
14579 if not Is_Character_Type (T) then
14580 Set_Is_In_ALFA (T);
14583 -- Set Discard_Names if configuration pragma set, or if there is
14584 -- a parameterless pragma in the current declarative region
14586 if Global_Discard_Names
14587 or else Discard_Names (Scope (T))
14589 Set_Discard_Names (T);
14592 -- Process end label if there is one
14594 if Present (Def) then
14595 Process_End_Label (Def, 'e', T);
14597 end Enumeration_Type_Declaration;
14599 ---------------------------------
14600 -- Expand_To_Stored_Constraint --
14601 ---------------------------------
14603 function Expand_To_Stored_Constraint
14605 Constraint : Elist_Id) return Elist_Id
14607 Explicitly_Discriminated_Type : Entity_Id;
14608 Expansion : Elist_Id;
14609 Discriminant : Entity_Id;
14611 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14612 -- Find the nearest type that actually specifies discriminants
14614 ---------------------------------
14615 -- Type_With_Explicit_Discrims --
14616 ---------------------------------
14618 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14619 Typ : constant E := Base_Type (Id);
14622 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14623 if Present (Full_View (Typ)) then
14624 return Type_With_Explicit_Discrims (Full_View (Typ));
14628 if Has_Discriminants (Typ) then
14633 if Etype (Typ) = Typ then
14635 elsif Has_Discriminants (Typ) then
14638 return Type_With_Explicit_Discrims (Etype (Typ));
14641 end Type_With_Explicit_Discrims;
14643 -- Start of processing for Expand_To_Stored_Constraint
14647 or else Is_Empty_Elmt_List (Constraint)
14652 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14654 if No (Explicitly_Discriminated_Type) then
14658 Expansion := New_Elmt_List;
14661 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14662 while Present (Discriminant) loop
14664 Get_Discriminant_Value (
14665 Discriminant, Explicitly_Discriminated_Type, Constraint),
14667 Next_Stored_Discriminant (Discriminant);
14671 end Expand_To_Stored_Constraint;
14673 ---------------------------
14674 -- Find_Hidden_Interface --
14675 ---------------------------
14677 function Find_Hidden_Interface
14679 Dest : Elist_Id) return Entity_Id
14682 Iface_Elmt : Elmt_Id;
14685 if Present (Src) and then Present (Dest) then
14686 Iface_Elmt := First_Elmt (Src);
14687 while Present (Iface_Elmt) loop
14688 Iface := Node (Iface_Elmt);
14690 if Is_Interface (Iface)
14691 and then not Contain_Interface (Iface, Dest)
14696 Next_Elmt (Iface_Elmt);
14701 end Find_Hidden_Interface;
14703 --------------------
14704 -- Find_Type_Name --
14705 --------------------
14707 function Find_Type_Name (N : Node_Id) return Entity_Id is
14708 Id : constant Entity_Id := Defining_Identifier (N);
14710 New_Id : Entity_Id;
14711 Prev_Par : Node_Id;
14713 procedure Tag_Mismatch;
14714 -- Diagnose a tagged partial view whose full view is untagged.
14715 -- We post the message on the full view, with a reference to
14716 -- the previous partial view. The partial view can be private
14717 -- or incomplete, and these are handled in a different manner,
14718 -- so we determine the position of the error message from the
14719 -- respective slocs of both.
14725 procedure Tag_Mismatch is
14727 if Sloc (Prev) < Sloc (Id) then
14728 if Ada_Version >= Ada_2012
14729 and then Nkind (N) = N_Private_Type_Declaration
14732 ("declaration of private } must be a tagged type ", Id, Prev);
14735 ("full declaration of } must be a tagged type ", Id, Prev);
14738 if Ada_Version >= Ada_2012
14739 and then Nkind (N) = N_Private_Type_Declaration
14742 ("declaration of private } must be a tagged type ", Prev, Id);
14745 ("full declaration of } must be a tagged type ", Prev, Id);
14750 -- Start of processing for Find_Type_Name
14753 -- Find incomplete declaration, if one was given
14755 Prev := Current_Entity_In_Scope (Id);
14757 -- New type declaration
14763 -- Previous declaration exists
14766 Prev_Par := Parent (Prev);
14768 -- Error if not incomplete/private case except if previous
14769 -- declaration is implicit, etc. Enter_Name will emit error if
14772 if not Is_Incomplete_Or_Private_Type (Prev) then
14776 -- Check invalid completion of private or incomplete type
14778 elsif not Nkind_In (N, N_Full_Type_Declaration,
14779 N_Task_Type_Declaration,
14780 N_Protected_Type_Declaration)
14782 (Ada_Version < Ada_2012
14783 or else not Is_Incomplete_Type (Prev)
14784 or else not Nkind_In (N, N_Private_Type_Declaration,
14785 N_Private_Extension_Declaration))
14787 -- Completion must be a full type declarations (RM 7.3(4))
14789 Error_Msg_Sloc := Sloc (Prev);
14790 Error_Msg_NE ("invalid completion of }", Id, Prev);
14792 -- Set scope of Id to avoid cascaded errors. Entity is never
14793 -- examined again, except when saving globals in generics.
14795 Set_Scope (Id, Current_Scope);
14798 -- If this is a repeated incomplete declaration, no further
14799 -- checks are possible.
14801 if Nkind (N) = N_Incomplete_Type_Declaration then
14805 -- Case of full declaration of incomplete type
14807 elsif Ekind (Prev) = E_Incomplete_Type
14808 and then (Ada_Version < Ada_2012
14809 or else No (Full_View (Prev))
14810 or else not Is_Private_Type (Full_View (Prev)))
14813 -- Indicate that the incomplete declaration has a matching full
14814 -- declaration. The defining occurrence of the incomplete
14815 -- declaration remains the visible one, and the procedure
14816 -- Get_Full_View dereferences it whenever the type is used.
14818 if Present (Full_View (Prev)) then
14819 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14822 Set_Full_View (Prev, Id);
14823 Append_Entity (Id, Current_Scope);
14824 Set_Is_Public (Id, Is_Public (Prev));
14825 Set_Is_Internal (Id);
14828 -- If the incomplete view is tagged, a class_wide type has been
14829 -- created already. Use it for the private type as well, in order
14830 -- to prevent multiple incompatible class-wide types that may be
14831 -- created for self-referential anonymous access components.
14833 if Is_Tagged_Type (Prev)
14834 and then Present (Class_Wide_Type (Prev))
14836 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14837 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14838 Set_Etype (Class_Wide_Type (Id), Id);
14841 -- Case of full declaration of private type
14844 -- If the private type was a completion of an incomplete type then
14845 -- update Prev to reference the private type
14847 if Ada_Version >= Ada_2012
14848 and then Ekind (Prev) = E_Incomplete_Type
14849 and then Present (Full_View (Prev))
14850 and then Is_Private_Type (Full_View (Prev))
14852 Prev := Full_View (Prev);
14853 Prev_Par := Parent (Prev);
14856 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14857 if Etype (Prev) /= Prev then
14859 -- Prev is a private subtype or a derived type, and needs
14862 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14865 elsif Ekind (Prev) = E_Private_Type
14866 and then Nkind_In (N, N_Task_Type_Declaration,
14867 N_Protected_Type_Declaration)
14870 ("completion of nonlimited type cannot be limited", N);
14872 elsif Ekind (Prev) = E_Record_Type_With_Private
14873 and then Nkind_In (N, N_Task_Type_Declaration,
14874 N_Protected_Type_Declaration)
14876 if not Is_Limited_Record (Prev) then
14878 ("completion of nonlimited type cannot be limited", N);
14880 elsif No (Interface_List (N)) then
14882 ("completion of tagged private type must be tagged",
14886 elsif Nkind (N) = N_Full_Type_Declaration
14888 Nkind (Type_Definition (N)) = N_Record_Definition
14889 and then Interface_Present (Type_Definition (N))
14892 ("completion of private type cannot be an interface", N);
14895 -- Ada 2005 (AI-251): Private extension declaration of a task
14896 -- type or a protected type. This case arises when covering
14897 -- interface types.
14899 elsif Nkind_In (N, N_Task_Type_Declaration,
14900 N_Protected_Type_Declaration)
14904 elsif Nkind (N) /= N_Full_Type_Declaration
14905 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14908 ("full view of private extension must be an extension", N);
14910 elsif not (Abstract_Present (Parent (Prev)))
14911 and then Abstract_Present (Type_Definition (N))
14914 ("full view of non-abstract extension cannot be abstract", N);
14917 if not In_Private_Part (Current_Scope) then
14919 ("declaration of full view must appear in private part", N);
14922 Copy_And_Swap (Prev, Id);
14923 Set_Has_Private_Declaration (Prev);
14924 Set_Has_Private_Declaration (Id);
14926 -- If no error, propagate freeze_node from private to full view.
14927 -- It may have been generated for an early operational item.
14929 if Present (Freeze_Node (Id))
14930 and then Serious_Errors_Detected = 0
14931 and then No (Full_View (Id))
14933 Set_Freeze_Node (Prev, Freeze_Node (Id));
14934 Set_Freeze_Node (Id, Empty);
14935 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
14938 Set_Full_View (Id, Prev);
14942 -- Verify that full declaration conforms to partial one
14944 if Is_Incomplete_Or_Private_Type (Prev)
14945 and then Present (Discriminant_Specifications (Prev_Par))
14947 if Present (Discriminant_Specifications (N)) then
14948 if Ekind (Prev) = E_Incomplete_Type then
14949 Check_Discriminant_Conformance (N, Prev, Prev);
14951 Check_Discriminant_Conformance (N, Prev, Id);
14956 ("missing discriminants in full type declaration", N);
14958 -- To avoid cascaded errors on subsequent use, share the
14959 -- discriminants of the partial view.
14961 Set_Discriminant_Specifications (N,
14962 Discriminant_Specifications (Prev_Par));
14966 -- A prior untagged partial view can have an associated class-wide
14967 -- type due to use of the class attribute, and in this case the full
14968 -- type must also be tagged. This Ada 95 usage is deprecated in favor
14969 -- of incomplete tagged declarations, but we check for it.
14972 and then (Is_Tagged_Type (Prev)
14973 or else Present (Class_Wide_Type (Prev)))
14975 -- Ada 2012 (AI05-0162): A private type may be the completion of
14976 -- an incomplete type
14978 if Ada_Version >= Ada_2012
14979 and then Is_Incomplete_Type (Prev)
14980 and then Nkind_In (N, N_Private_Type_Declaration,
14981 N_Private_Extension_Declaration)
14983 -- No need to check private extensions since they are tagged
14985 if Nkind (N) = N_Private_Type_Declaration
14986 and then not Tagged_Present (N)
14991 -- The full declaration is either a tagged type (including
14992 -- a synchronized type that implements interfaces) or a
14993 -- type extension, otherwise this is an error.
14995 elsif Nkind_In (N, N_Task_Type_Declaration,
14996 N_Protected_Type_Declaration)
14998 if No (Interface_List (N))
14999 and then not Error_Posted (N)
15004 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15006 -- Indicate that the previous declaration (tagged incomplete
15007 -- or private declaration) requires the same on the full one.
15009 if not Tagged_Present (Type_Definition (N)) then
15011 Set_Is_Tagged_Type (Id);
15014 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15015 if No (Record_Extension_Part (Type_Definition (N))) then
15017 ("full declaration of } must be a record extension",
15020 -- Set some attributes to produce a usable full view
15022 Set_Is_Tagged_Type (Id);
15032 end Find_Type_Name;
15034 -------------------------
15035 -- Find_Type_Of_Object --
15036 -------------------------
15038 function Find_Type_Of_Object
15039 (Obj_Def : Node_Id;
15040 Related_Nod : Node_Id) return Entity_Id
15042 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15043 P : Node_Id := Parent (Obj_Def);
15048 -- If the parent is a component_definition node we climb to the
15049 -- component_declaration node
15051 if Nkind (P) = N_Component_Definition then
15055 -- Case of an anonymous array subtype
15057 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15058 N_Unconstrained_Array_Definition)
15061 Array_Type_Declaration (T, Obj_Def);
15063 -- Create an explicit subtype whenever possible
15065 elsif Nkind (P) /= N_Component_Declaration
15066 and then Def_Kind = N_Subtype_Indication
15068 -- Base name of subtype on object name, which will be unique in
15069 -- the current scope.
15071 -- If this is a duplicate declaration, return base type, to avoid
15072 -- generating duplicate anonymous types.
15074 if Error_Posted (P) then
15075 Analyze (Subtype_Mark (Obj_Def));
15076 return Entity (Subtype_Mark (Obj_Def));
15081 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15083 T := Make_Defining_Identifier (Sloc (P), Nam);
15085 Insert_Action (Obj_Def,
15086 Make_Subtype_Declaration (Sloc (P),
15087 Defining_Identifier => T,
15088 Subtype_Indication => Relocate_Node (Obj_Def)));
15090 -- This subtype may need freezing, and this will not be done
15091 -- automatically if the object declaration is not in declarative
15092 -- part. Since this is an object declaration, the type cannot always
15093 -- be frozen here. Deferred constants do not freeze their type
15094 -- (which often enough will be private).
15096 if Nkind (P) = N_Object_Declaration
15097 and then Constant_Present (P)
15098 and then No (Expression (P))
15102 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15105 -- Ada 2005 AI-406: the object definition in an object declaration
15106 -- can be an access definition.
15108 elsif Def_Kind = N_Access_Definition then
15109 T := Access_Definition (Related_Nod, Obj_Def);
15110 Set_Is_Local_Anonymous_Access (T);
15112 -- Otherwise, the object definition is just a subtype_mark
15115 T := Process_Subtype (Obj_Def, Related_Nod);
15117 -- If expansion is disabled an object definition that is an aggregate
15118 -- will not get expanded and may lead to scoping problems in the back
15119 -- end, if the object is referenced in an inner scope. In that case
15120 -- create an itype reference for the object definition now. This
15121 -- may be redundant in some cases, but harmless.
15124 and then Nkind (Related_Nod) = N_Object_Declaration
15127 Build_Itype_Reference (T, Related_Nod);
15132 end Find_Type_Of_Object;
15134 --------------------------------
15135 -- Find_Type_Of_Subtype_Indic --
15136 --------------------------------
15138 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15142 -- Case of subtype mark with a constraint
15144 if Nkind (S) = N_Subtype_Indication then
15145 Find_Type (Subtype_Mark (S));
15146 Typ := Entity (Subtype_Mark (S));
15149 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15152 ("incorrect constraint for this kind of type", Constraint (S));
15153 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15156 -- Otherwise we have a subtype mark without a constraint
15158 elsif Error_Posted (S) then
15159 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15167 -- Check No_Wide_Characters restriction
15169 Check_Wide_Character_Restriction (Typ, S);
15172 end Find_Type_Of_Subtype_Indic;
15174 -------------------------------------
15175 -- Floating_Point_Type_Declaration --
15176 -------------------------------------
15178 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15179 Digs : constant Node_Id := Digits_Expression (Def);
15180 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15182 Base_Typ : Entity_Id;
15183 Implicit_Base : Entity_Id;
15186 function Can_Derive_From (E : Entity_Id) return Boolean;
15187 -- Find if given digits value, and possibly a specified range, allows
15188 -- derivation from specified type
15190 function Find_Base_Type return Entity_Id;
15191 -- Find a predefined base type that Def can derive from, or generate
15192 -- an error and substitute Long_Long_Float if none exists.
15194 ---------------------
15195 -- Can_Derive_From --
15196 ---------------------
15198 function Can_Derive_From (E : Entity_Id) return Boolean is
15199 Spec : constant Entity_Id := Real_Range_Specification (Def);
15202 if Digs_Val > Digits_Value (E) then
15206 if Present (Spec) then
15207 if Expr_Value_R (Type_Low_Bound (E)) >
15208 Expr_Value_R (Low_Bound (Spec))
15213 if Expr_Value_R (Type_High_Bound (E)) <
15214 Expr_Value_R (High_Bound (Spec))
15221 end Can_Derive_From;
15223 --------------------
15224 -- Find_Base_Type --
15225 --------------------
15227 function Find_Base_Type return Entity_Id is
15228 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15231 -- Iterate over the predefined types in order, returning the first
15232 -- one that Def can derive from.
15234 while Present (Choice) loop
15235 if Can_Derive_From (Node (Choice)) then
15236 return Node (Choice);
15239 Next_Elmt (Choice);
15242 -- If we can't derive from any existing type, use Long_Long_Float
15243 -- and give appropriate message explaining the problem.
15245 if Digs_Val > Max_Digs_Val then
15246 -- It might be the case that there is a type with the requested
15247 -- range, just not the combination of digits and range.
15250 ("no predefined type has requested range and precision",
15251 Real_Range_Specification (Def));
15255 ("range too large for any predefined type",
15256 Real_Range_Specification (Def));
15259 return Standard_Long_Long_Float;
15260 end Find_Base_Type;
15262 -- Start of processing for Floating_Point_Type_Declaration
15265 Check_Restriction (No_Floating_Point, Def);
15267 -- Create an implicit base type
15270 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15272 -- Analyze and verify digits value
15274 Analyze_And_Resolve (Digs, Any_Integer);
15275 Check_Digits_Expression (Digs);
15276 Digs_Val := Expr_Value (Digs);
15278 -- Process possible range spec and find correct type to derive from
15280 Process_Real_Range_Specification (Def);
15282 -- Check that requested number of digits is not too high.
15284 if Digs_Val > Max_Digs_Val then
15285 -- The check for Max_Base_Digits may be somewhat expensive, as it
15286 -- requires reading System, so only do it when necessary.
15289 Max_Base_Digits : constant Uint :=
15292 (Parent (RTE (RE_Max_Base_Digits))));
15295 if Digs_Val > Max_Base_Digits then
15296 Error_Msg_Uint_1 := Max_Base_Digits;
15297 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15299 elsif No (Real_Range_Specification (Def)) then
15300 Error_Msg_Uint_1 := Max_Digs_Val;
15301 Error_Msg_N ("types with more than ^ digits need range spec "
15302 & "('R'M 3.5.7(6))", Digs);
15307 -- Find a suitable type to derive from or complain and use a substitute
15309 Base_Typ := Find_Base_Type;
15311 -- If there are bounds given in the declaration use them as the bounds
15312 -- of the type, otherwise use the bounds of the predefined base type
15313 -- that was chosen based on the Digits value.
15315 if Present (Real_Range_Specification (Def)) then
15316 Set_Scalar_Range (T, Real_Range_Specification (Def));
15317 Set_Is_Constrained (T);
15319 -- The bounds of this range must be converted to machine numbers
15320 -- in accordance with RM 4.9(38).
15322 Bound := Type_Low_Bound (T);
15324 if Nkind (Bound) = N_Real_Literal then
15326 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15327 Set_Is_Machine_Number (Bound);
15330 Bound := Type_High_Bound (T);
15332 if Nkind (Bound) = N_Real_Literal then
15334 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15335 Set_Is_Machine_Number (Bound);
15339 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15342 -- Complete definition of implicit base and declared first subtype
15344 Set_Etype (Implicit_Base, Base_Typ);
15346 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15347 Set_Size_Info (Implicit_Base, (Base_Typ));
15348 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15349 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15350 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15351 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15353 Set_Ekind (T, E_Floating_Point_Subtype);
15354 Set_Etype (T, Implicit_Base);
15356 Set_Size_Info (T, (Implicit_Base));
15357 Set_RM_Size (T, RM_Size (Implicit_Base));
15358 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15359 Set_Digits_Value (T, Digs_Val);
15360 end Floating_Point_Type_Declaration;
15362 ----------------------------
15363 -- Get_Discriminant_Value --
15364 ----------------------------
15366 -- This is the situation:
15368 -- There is a non-derived type
15370 -- type T0 (Dx, Dy, Dz...)
15372 -- There are zero or more levels of derivation, with each derivation
15373 -- either purely inheriting the discriminants, or defining its own.
15375 -- type Ti is new Ti-1
15377 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15379 -- subtype Ti is ...
15381 -- The subtype issue is avoided by the use of Original_Record_Component,
15382 -- and the fact that derived subtypes also derive the constraints.
15384 -- This chain leads back from
15386 -- Typ_For_Constraint
15388 -- Typ_For_Constraint has discriminants, and the value for each
15389 -- discriminant is given by its corresponding Elmt of Constraints.
15391 -- Discriminant is some discriminant in this hierarchy
15393 -- We need to return its value
15395 -- We do this by recursively searching each level, and looking for
15396 -- Discriminant. Once we get to the bottom, we start backing up
15397 -- returning the value for it which may in turn be a discriminant
15398 -- further up, so on the backup we continue the substitution.
15400 function Get_Discriminant_Value
15401 (Discriminant : Entity_Id;
15402 Typ_For_Constraint : Entity_Id;
15403 Constraint : Elist_Id) return Node_Id
15405 function Search_Derivation_Levels
15407 Discrim_Values : Elist_Id;
15408 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15409 -- This is the routine that performs the recursive search of levels
15410 -- as described above.
15412 ------------------------------
15413 -- Search_Derivation_Levels --
15414 ------------------------------
15416 function Search_Derivation_Levels
15418 Discrim_Values : Elist_Id;
15419 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15423 Result : Node_Or_Entity_Id;
15424 Result_Entity : Node_Id;
15427 -- If inappropriate type, return Error, this happens only in
15428 -- cascaded error situations, and we want to avoid a blow up.
15430 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15434 -- Look deeper if possible. Use Stored_Constraints only for
15435 -- untagged types. For tagged types use the given constraint.
15436 -- This asymmetry needs explanation???
15438 if not Stored_Discrim_Values
15439 and then Present (Stored_Constraint (Ti))
15440 and then not Is_Tagged_Type (Ti)
15443 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15446 Td : constant Entity_Id := Etype (Ti);
15450 Result := Discriminant;
15453 if Present (Stored_Constraint (Ti)) then
15455 Search_Derivation_Levels
15456 (Td, Stored_Constraint (Ti), True);
15459 Search_Derivation_Levels
15460 (Td, Discrim_Values, Stored_Discrim_Values);
15466 -- Extra underlying places to search, if not found above. For
15467 -- concurrent types, the relevant discriminant appears in the
15468 -- corresponding record. For a type derived from a private type
15469 -- without discriminant, the full view inherits the discriminants
15470 -- of the full view of the parent.
15472 if Result = Discriminant then
15473 if Is_Concurrent_Type (Ti)
15474 and then Present (Corresponding_Record_Type (Ti))
15477 Search_Derivation_Levels (
15478 Corresponding_Record_Type (Ti),
15480 Stored_Discrim_Values);
15482 elsif Is_Private_Type (Ti)
15483 and then not Has_Discriminants (Ti)
15484 and then Present (Full_View (Ti))
15485 and then Etype (Full_View (Ti)) /= Ti
15488 Search_Derivation_Levels (
15491 Stored_Discrim_Values);
15495 -- If Result is not a (reference to a) discriminant, return it,
15496 -- otherwise set Result_Entity to the discriminant.
15498 if Nkind (Result) = N_Defining_Identifier then
15499 pragma Assert (Result = Discriminant);
15500 Result_Entity := Result;
15503 if not Denotes_Discriminant (Result) then
15507 Result_Entity := Entity (Result);
15510 -- See if this level of derivation actually has discriminants
15511 -- because tagged derivations can add them, hence the lower
15512 -- levels need not have any.
15514 if not Has_Discriminants (Ti) then
15518 -- Scan Ti's discriminants for Result_Entity,
15519 -- and return its corresponding value, if any.
15521 Result_Entity := Original_Record_Component (Result_Entity);
15523 Assoc := First_Elmt (Discrim_Values);
15525 if Stored_Discrim_Values then
15526 Disc := First_Stored_Discriminant (Ti);
15528 Disc := First_Discriminant (Ti);
15531 while Present (Disc) loop
15532 pragma Assert (Present (Assoc));
15534 if Original_Record_Component (Disc) = Result_Entity then
15535 return Node (Assoc);
15540 if Stored_Discrim_Values then
15541 Next_Stored_Discriminant (Disc);
15543 Next_Discriminant (Disc);
15547 -- Could not find it
15550 end Search_Derivation_Levels;
15554 Result : Node_Or_Entity_Id;
15556 -- Start of processing for Get_Discriminant_Value
15559 -- ??? This routine is a gigantic mess and will be deleted. For the
15560 -- time being just test for the trivial case before calling recurse.
15562 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15568 D := First_Discriminant (Typ_For_Constraint);
15569 E := First_Elmt (Constraint);
15570 while Present (D) loop
15571 if Chars (D) = Chars (Discriminant) then
15575 Next_Discriminant (D);
15581 Result := Search_Derivation_Levels
15582 (Typ_For_Constraint, Constraint, False);
15584 -- ??? hack to disappear when this routine is gone
15586 if Nkind (Result) = N_Defining_Identifier then
15592 D := First_Discriminant (Typ_For_Constraint);
15593 E := First_Elmt (Constraint);
15594 while Present (D) loop
15595 if Corresponding_Discriminant (D) = Discriminant then
15599 Next_Discriminant (D);
15605 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15607 end Get_Discriminant_Value;
15609 --------------------------
15610 -- Has_Range_Constraint --
15611 --------------------------
15613 function Has_Range_Constraint (N : Node_Id) return Boolean is
15614 C : constant Node_Id := Constraint (N);
15617 if Nkind (C) = N_Range_Constraint then
15620 elsif Nkind (C) = N_Digits_Constraint then
15622 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15624 Present (Range_Constraint (C));
15626 elsif Nkind (C) = N_Delta_Constraint then
15627 return Present (Range_Constraint (C));
15632 end Has_Range_Constraint;
15634 ------------------------
15635 -- Inherit_Components --
15636 ------------------------
15638 function Inherit_Components
15640 Parent_Base : Entity_Id;
15641 Derived_Base : Entity_Id;
15642 Is_Tagged : Boolean;
15643 Inherit_Discr : Boolean;
15644 Discs : Elist_Id) return Elist_Id
15646 Assoc_List : constant Elist_Id := New_Elmt_List;
15648 procedure Inherit_Component
15649 (Old_C : Entity_Id;
15650 Plain_Discrim : Boolean := False;
15651 Stored_Discrim : Boolean := False);
15652 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15653 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15654 -- True, Old_C is a stored discriminant. If they are both false then
15655 -- Old_C is a regular component.
15657 -----------------------
15658 -- Inherit_Component --
15659 -----------------------
15661 procedure Inherit_Component
15662 (Old_C : Entity_Id;
15663 Plain_Discrim : Boolean := False;
15664 Stored_Discrim : Boolean := False)
15666 New_C : constant Entity_Id := New_Copy (Old_C);
15668 Discrim : Entity_Id;
15669 Corr_Discrim : Entity_Id;
15672 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15674 Set_Parent (New_C, Parent (Old_C));
15676 -- Regular discriminants and components must be inserted in the scope
15677 -- of the Derived_Base. Do it here.
15679 if not Stored_Discrim then
15680 Enter_Name (New_C);
15683 -- For tagged types the Original_Record_Component must point to
15684 -- whatever this field was pointing to in the parent type. This has
15685 -- already been achieved by the call to New_Copy above.
15687 if not Is_Tagged then
15688 Set_Original_Record_Component (New_C, New_C);
15691 -- If we have inherited a component then see if its Etype contains
15692 -- references to Parent_Base discriminants. In this case, replace
15693 -- these references with the constraints given in Discs. We do not
15694 -- do this for the partial view of private types because this is
15695 -- not needed (only the components of the full view will be used
15696 -- for code generation) and cause problem. We also avoid this
15697 -- transformation in some error situations.
15699 if Ekind (New_C) = E_Component then
15700 if (Is_Private_Type (Derived_Base)
15701 and then not Is_Generic_Type (Derived_Base))
15702 or else (Is_Empty_Elmt_List (Discs)
15703 and then not Expander_Active)
15705 Set_Etype (New_C, Etype (Old_C));
15708 -- The current component introduces a circularity of the
15711 -- limited with Pack_2;
15712 -- package Pack_1 is
15713 -- type T_1 is tagged record
15714 -- Comp : access Pack_2.T_2;
15720 -- package Pack_2 is
15721 -- type T_2 is new Pack_1.T_1 with ...;
15726 Constrain_Component_Type
15727 (Old_C, Derived_Base, N, Parent_Base, Discs));
15731 -- In derived tagged types it is illegal to reference a non
15732 -- discriminant component in the parent type. To catch this, mark
15733 -- these components with an Ekind of E_Void. This will be reset in
15734 -- Record_Type_Definition after processing the record extension of
15735 -- the derived type.
15737 -- If the declaration is a private extension, there is no further
15738 -- record extension to process, and the components retain their
15739 -- current kind, because they are visible at this point.
15741 if Is_Tagged and then Ekind (New_C) = E_Component
15742 and then Nkind (N) /= N_Private_Extension_Declaration
15744 Set_Ekind (New_C, E_Void);
15747 if Plain_Discrim then
15748 Set_Corresponding_Discriminant (New_C, Old_C);
15749 Build_Discriminal (New_C);
15751 -- If we are explicitly inheriting a stored discriminant it will be
15752 -- completely hidden.
15754 elsif Stored_Discrim then
15755 Set_Corresponding_Discriminant (New_C, Empty);
15756 Set_Discriminal (New_C, Empty);
15757 Set_Is_Completely_Hidden (New_C);
15759 -- Set the Original_Record_Component of each discriminant in the
15760 -- derived base to point to the corresponding stored that we just
15763 Discrim := First_Discriminant (Derived_Base);
15764 while Present (Discrim) loop
15765 Corr_Discrim := Corresponding_Discriminant (Discrim);
15767 -- Corr_Discrim could be missing in an error situation
15769 if Present (Corr_Discrim)
15770 and then Original_Record_Component (Corr_Discrim) = Old_C
15772 Set_Original_Record_Component (Discrim, New_C);
15775 Next_Discriminant (Discrim);
15778 Append_Entity (New_C, Derived_Base);
15781 if not Is_Tagged then
15782 Append_Elmt (Old_C, Assoc_List);
15783 Append_Elmt (New_C, Assoc_List);
15785 end Inherit_Component;
15787 -- Variables local to Inherit_Component
15789 Loc : constant Source_Ptr := Sloc (N);
15791 Parent_Discrim : Entity_Id;
15792 Stored_Discrim : Entity_Id;
15794 Component : Entity_Id;
15796 -- Start of processing for Inherit_Components
15799 if not Is_Tagged then
15800 Append_Elmt (Parent_Base, Assoc_List);
15801 Append_Elmt (Derived_Base, Assoc_List);
15804 -- Inherit parent discriminants if needed
15806 if Inherit_Discr then
15807 Parent_Discrim := First_Discriminant (Parent_Base);
15808 while Present (Parent_Discrim) loop
15809 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15810 Next_Discriminant (Parent_Discrim);
15814 -- Create explicit stored discrims for untagged types when necessary
15816 if not Has_Unknown_Discriminants (Derived_Base)
15817 and then Has_Discriminants (Parent_Base)
15818 and then not Is_Tagged
15821 or else First_Discriminant (Parent_Base) /=
15822 First_Stored_Discriminant (Parent_Base))
15824 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15825 while Present (Stored_Discrim) loop
15826 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15827 Next_Stored_Discriminant (Stored_Discrim);
15831 -- See if we can apply the second transformation for derived types, as
15832 -- explained in point 6. in the comments above Build_Derived_Record_Type
15833 -- This is achieved by appending Derived_Base discriminants into Discs,
15834 -- which has the side effect of returning a non empty Discs list to the
15835 -- caller of Inherit_Components, which is what we want. This must be
15836 -- done for private derived types if there are explicit stored
15837 -- discriminants, to ensure that we can retrieve the values of the
15838 -- constraints provided in the ancestors.
15841 and then Is_Empty_Elmt_List (Discs)
15842 and then Present (First_Discriminant (Derived_Base))
15844 (not Is_Private_Type (Derived_Base)
15845 or else Is_Completely_Hidden
15846 (First_Stored_Discriminant (Derived_Base))
15847 or else Is_Generic_Type (Derived_Base))
15849 D := First_Discriminant (Derived_Base);
15850 while Present (D) loop
15851 Append_Elmt (New_Reference_To (D, Loc), Discs);
15852 Next_Discriminant (D);
15856 -- Finally, inherit non-discriminant components unless they are not
15857 -- visible because defined or inherited from the full view of the
15858 -- parent. Don't inherit the _parent field of the parent type.
15860 Component := First_Entity (Parent_Base);
15861 while Present (Component) loop
15863 -- Ada 2005 (AI-251): Do not inherit components associated with
15864 -- secondary tags of the parent.
15866 if Ekind (Component) = E_Component
15867 and then Present (Related_Type (Component))
15871 elsif Ekind (Component) /= E_Component
15872 or else Chars (Component) = Name_uParent
15876 -- If the derived type is within the parent type's declarative
15877 -- region, then the components can still be inherited even though
15878 -- they aren't visible at this point. This can occur for cases
15879 -- such as within public child units where the components must
15880 -- become visible upon entering the child unit's private part.
15882 elsif not Is_Visible_Component (Component)
15883 and then not In_Open_Scopes (Scope (Parent_Base))
15887 elsif Ekind_In (Derived_Base, E_Private_Type,
15888 E_Limited_Private_Type)
15893 Inherit_Component (Component);
15896 Next_Entity (Component);
15899 -- For tagged derived types, inherited discriminants cannot be used in
15900 -- component declarations of the record extension part. To achieve this
15901 -- we mark the inherited discriminants as not visible.
15903 if Is_Tagged and then Inherit_Discr then
15904 D := First_Discriminant (Derived_Base);
15905 while Present (D) loop
15906 Set_Is_Immediately_Visible (D, False);
15907 Next_Discriminant (D);
15912 end Inherit_Components;
15914 -----------------------
15915 -- Is_Constant_Bound --
15916 -----------------------
15918 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
15920 if Compile_Time_Known_Value (Exp) then
15923 elsif Is_Entity_Name (Exp)
15924 and then Present (Entity (Exp))
15926 return Is_Constant_Object (Entity (Exp))
15927 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
15929 elsif Nkind (Exp) in N_Binary_Op then
15930 return Is_Constant_Bound (Left_Opnd (Exp))
15931 and then Is_Constant_Bound (Right_Opnd (Exp))
15932 and then Scope (Entity (Exp)) = Standard_Standard;
15937 end Is_Constant_Bound;
15939 -----------------------
15940 -- Is_Null_Extension --
15941 -----------------------
15943 function Is_Null_Extension (T : Entity_Id) return Boolean is
15944 Type_Decl : constant Node_Id := Parent (Base_Type (T));
15945 Comp_List : Node_Id;
15949 if Nkind (Type_Decl) /= N_Full_Type_Declaration
15950 or else not Is_Tagged_Type (T)
15951 or else Nkind (Type_Definition (Type_Decl)) /=
15952 N_Derived_Type_Definition
15953 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
15959 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
15961 if Present (Discriminant_Specifications (Type_Decl)) then
15964 elsif Present (Comp_List)
15965 and then Is_Non_Empty_List (Component_Items (Comp_List))
15967 Comp := First (Component_Items (Comp_List));
15969 -- Only user-defined components are relevant. The component list
15970 -- may also contain a parent component and internal components
15971 -- corresponding to secondary tags, but these do not determine
15972 -- whether this is a null extension.
15974 while Present (Comp) loop
15975 if Comes_From_Source (Comp) then
15986 end Is_Null_Extension;
15988 ------------------------------
15989 -- Is_Valid_Constraint_Kind --
15990 ------------------------------
15992 function Is_Valid_Constraint_Kind
15993 (T_Kind : Type_Kind;
15994 Constraint_Kind : Node_Kind) return Boolean
15998 when Enumeration_Kind |
16000 return Constraint_Kind = N_Range_Constraint;
16002 when Decimal_Fixed_Point_Kind =>
16003 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16004 N_Range_Constraint);
16006 when Ordinary_Fixed_Point_Kind =>
16007 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16008 N_Range_Constraint);
16011 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16012 N_Range_Constraint);
16019 E_Incomplete_Type |
16022 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16025 return True; -- Error will be detected later
16027 end Is_Valid_Constraint_Kind;
16029 --------------------------
16030 -- Is_Visible_Component --
16031 --------------------------
16033 function Is_Visible_Component (C : Entity_Id) return Boolean is
16034 Original_Comp : Entity_Id := Empty;
16035 Original_Scope : Entity_Id;
16036 Type_Scope : Entity_Id;
16038 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16039 -- Check whether parent type of inherited component is declared locally,
16040 -- possibly within a nested package or instance. The current scope is
16041 -- the derived record itself.
16043 -------------------
16044 -- Is_Local_Type --
16045 -------------------
16047 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16051 Scop := Scope (Typ);
16052 while Present (Scop)
16053 and then Scop /= Standard_Standard
16055 if Scop = Scope (Current_Scope) then
16059 Scop := Scope (Scop);
16065 -- Start of processing for Is_Visible_Component
16068 if Ekind_In (C, E_Component, E_Discriminant) then
16069 Original_Comp := Original_Record_Component (C);
16072 if No (Original_Comp) then
16074 -- Premature usage, or previous error
16079 Original_Scope := Scope (Original_Comp);
16080 Type_Scope := Scope (Base_Type (Scope (C)));
16083 -- This test only concerns tagged types
16085 if not Is_Tagged_Type (Original_Scope) then
16088 -- If it is _Parent or _Tag, there is no visibility issue
16090 elsif not Comes_From_Source (Original_Comp) then
16093 -- If we are in the body of an instantiation, the component is visible
16094 -- even when the parent type (possibly defined in an enclosing unit or
16095 -- in a parent unit) might not.
16097 elsif In_Instance_Body then
16100 -- Discriminants are always visible
16102 elsif Ekind (Original_Comp) = E_Discriminant
16103 and then not Has_Unknown_Discriminants (Original_Scope)
16107 -- If the component has been declared in an ancestor which is currently
16108 -- a private type, then it is not visible. The same applies if the
16109 -- component's containing type is not in an open scope and the original
16110 -- component's enclosing type is a visible full view of a private type
16111 -- (which can occur in cases where an attempt is being made to reference
16112 -- a component in a sibling package that is inherited from a visible
16113 -- component of a type in an ancestor package; the component in the
16114 -- sibling package should not be visible even though the component it
16115 -- inherited from is visible). This does not apply however in the case
16116 -- where the scope of the type is a private child unit, or when the
16117 -- parent comes from a local package in which the ancestor is currently
16118 -- visible. The latter suppression of visibility is needed for cases
16119 -- that are tested in B730006.
16121 elsif Is_Private_Type (Original_Scope)
16123 (not Is_Private_Descendant (Type_Scope)
16124 and then not In_Open_Scopes (Type_Scope)
16125 and then Has_Private_Declaration (Original_Scope))
16127 -- If the type derives from an entity in a formal package, there
16128 -- are no additional visible components.
16130 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16131 N_Formal_Package_Declaration
16135 -- if we are not in the private part of the current package, there
16136 -- are no additional visible components.
16138 elsif Ekind (Scope (Current_Scope)) = E_Package
16139 and then not In_Private_Part (Scope (Current_Scope))
16144 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16145 and then In_Open_Scopes (Scope (Original_Scope))
16146 and then Is_Local_Type (Type_Scope);
16149 -- There is another weird way in which a component may be invisible
16150 -- when the private and the full view are not derived from the same
16151 -- ancestor. Here is an example :
16153 -- type A1 is tagged record F1 : integer; end record;
16154 -- type A2 is new A1 with record F2 : integer; end record;
16155 -- type T is new A1 with private;
16157 -- type T is new A2 with null record;
16159 -- In this case, the full view of T inherits F1 and F2 but the private
16160 -- view inherits only F1
16164 Ancestor : Entity_Id := Scope (C);
16168 if Ancestor = Original_Scope then
16170 elsif Ancestor = Etype (Ancestor) then
16174 Ancestor := Etype (Ancestor);
16178 end Is_Visible_Component;
16180 --------------------------
16181 -- Make_Class_Wide_Type --
16182 --------------------------
16184 procedure Make_Class_Wide_Type (T : Entity_Id) is
16185 CW_Type : Entity_Id;
16187 Next_E : Entity_Id;
16190 -- The class wide type can have been defined by the partial view, in
16191 -- which case everything is already done.
16193 if Present (Class_Wide_Type (T)) then
16198 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16200 -- Inherit root type characteristics
16202 CW_Name := Chars (CW_Type);
16203 Next_E := Next_Entity (CW_Type);
16204 Copy_Node (T, CW_Type);
16205 Set_Comes_From_Source (CW_Type, False);
16206 Set_Chars (CW_Type, CW_Name);
16207 Set_Parent (CW_Type, Parent (T));
16208 Set_Next_Entity (CW_Type, Next_E);
16210 -- Ensure we have a new freeze node for the class-wide type. The partial
16211 -- view may have freeze action of its own, requiring a proper freeze
16212 -- node, and the same freeze node cannot be shared between the two
16215 Set_Has_Delayed_Freeze (CW_Type);
16216 Set_Freeze_Node (CW_Type, Empty);
16218 -- Customize the class-wide type: It has no prim. op., it cannot be
16219 -- abstract and its Etype points back to the specific root type.
16221 Set_Ekind (CW_Type, E_Class_Wide_Type);
16222 Set_Is_Tagged_Type (CW_Type, True);
16223 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16224 Set_Is_Abstract_Type (CW_Type, False);
16225 Set_Is_Constrained (CW_Type, False);
16226 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16228 if Ekind (T) = E_Class_Wide_Subtype then
16229 Set_Etype (CW_Type, Etype (Base_Type (T)));
16231 Set_Etype (CW_Type, T);
16234 -- If this is the class_wide type of a constrained subtype, it does
16235 -- not have discriminants.
16237 Set_Has_Discriminants (CW_Type,
16238 Has_Discriminants (T) and then not Is_Constrained (T));
16240 Set_Has_Unknown_Discriminants (CW_Type, True);
16241 Set_Class_Wide_Type (T, CW_Type);
16242 Set_Equivalent_Type (CW_Type, Empty);
16244 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16246 Set_Class_Wide_Type (CW_Type, CW_Type);
16247 end Make_Class_Wide_Type;
16253 procedure Make_Index
16255 Related_Nod : Node_Id;
16256 Related_Id : Entity_Id := Empty;
16257 Suffix_Index : Nat := 1;
16258 In_Iter_Schm : Boolean := False)
16262 Def_Id : Entity_Id := Empty;
16263 Found : Boolean := False;
16266 -- For a discrete range used in a constrained array definition and
16267 -- defined by a range, an implicit conversion to the predefined type
16268 -- INTEGER is assumed if each bound is either a numeric literal, a named
16269 -- number, or an attribute, and the type of both bounds (prior to the
16270 -- implicit conversion) is the type universal_integer. Otherwise, both
16271 -- bounds must be of the same discrete type, other than universal
16272 -- integer; this type must be determinable independently of the
16273 -- context, but using the fact that the type must be discrete and that
16274 -- both bounds must have the same type.
16276 -- Character literals also have a universal type in the absence of
16277 -- of additional context, and are resolved to Standard_Character.
16279 if Nkind (I) = N_Range then
16281 -- The index is given by a range constraint. The bounds are known
16282 -- to be of a consistent type.
16284 if not Is_Overloaded (I) then
16287 -- For universal bounds, choose the specific predefined type
16289 if T = Universal_Integer then
16290 T := Standard_Integer;
16292 elsif T = Any_Character then
16293 Ambiguous_Character (Low_Bound (I));
16295 T := Standard_Character;
16298 -- The node may be overloaded because some user-defined operators
16299 -- are available, but if a universal interpretation exists it is
16300 -- also the selected one.
16302 elsif Universal_Interpretation (I) = Universal_Integer then
16303 T := Standard_Integer;
16309 Ind : Interp_Index;
16313 Get_First_Interp (I, Ind, It);
16314 while Present (It.Typ) loop
16315 if Is_Discrete_Type (It.Typ) then
16318 and then not Covers (It.Typ, T)
16319 and then not Covers (T, It.Typ)
16321 Error_Msg_N ("ambiguous bounds in discrete range", I);
16329 Get_Next_Interp (Ind, It);
16332 if T = Any_Type then
16333 Error_Msg_N ("discrete type required for range", I);
16334 Set_Etype (I, Any_Type);
16337 elsif T = Universal_Integer then
16338 T := Standard_Integer;
16343 if not Is_Discrete_Type (T) then
16344 Error_Msg_N ("discrete type required for range", I);
16345 Set_Etype (I, Any_Type);
16349 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16350 and then Attribute_Name (Low_Bound (I)) = Name_First
16351 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16352 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16353 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16355 -- The type of the index will be the type of the prefix, as long
16356 -- as the upper bound is 'Last of the same type.
16358 Def_Id := Entity (Prefix (Low_Bound (I)));
16360 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16361 or else Attribute_Name (High_Bound (I)) /= Name_Last
16362 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16363 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16370 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16372 elsif Nkind (I) = N_Subtype_Indication then
16374 -- The index is given by a subtype with a range constraint
16376 T := Base_Type (Entity (Subtype_Mark (I)));
16378 if not Is_Discrete_Type (T) then
16379 Error_Msg_N ("discrete type required for range", I);
16380 Set_Etype (I, Any_Type);
16384 R := Range_Expression (Constraint (I));
16387 Process_Range_Expr_In_Decl
16388 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16390 elsif Nkind (I) = N_Attribute_Reference then
16392 -- The parser guarantees that the attribute is a RANGE attribute
16394 -- If the node denotes the range of a type mark, that is also the
16395 -- resulting type, and we do no need to create an Itype for it.
16397 if Is_Entity_Name (Prefix (I))
16398 and then Comes_From_Source (I)
16399 and then Is_Type (Entity (Prefix (I)))
16400 and then Is_Discrete_Type (Entity (Prefix (I)))
16402 Def_Id := Entity (Prefix (I));
16405 Analyze_And_Resolve (I);
16409 -- If none of the above, must be a subtype. We convert this to a
16410 -- range attribute reference because in the case of declared first
16411 -- named subtypes, the types in the range reference can be different
16412 -- from the type of the entity. A range attribute normalizes the
16413 -- reference and obtains the correct types for the bounds.
16415 -- This transformation is in the nature of an expansion, is only
16416 -- done if expansion is active. In particular, it is not done on
16417 -- formal generic types, because we need to retain the name of the
16418 -- original index for instantiation purposes.
16421 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16422 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16423 Set_Etype (I, Any_Integer);
16427 -- The type mark may be that of an incomplete type. It is only
16428 -- now that we can get the full view, previous analysis does
16429 -- not look specifically for a type mark.
16431 Set_Entity (I, Get_Full_View (Entity (I)));
16432 Set_Etype (I, Entity (I));
16433 Def_Id := Entity (I);
16435 if not Is_Discrete_Type (Def_Id) then
16436 Error_Msg_N ("discrete type required for index", I);
16437 Set_Etype (I, Any_Type);
16442 if Expander_Active then
16444 Make_Attribute_Reference (Sloc (I),
16445 Attribute_Name => Name_Range,
16446 Prefix => Relocate_Node (I)));
16448 -- The original was a subtype mark that does not freeze. This
16449 -- means that the rewritten version must not freeze either.
16451 Set_Must_Not_Freeze (I);
16452 Set_Must_Not_Freeze (Prefix (I));
16454 -- Is order critical??? if so, document why, if not
16455 -- use Analyze_And_Resolve
16457 Analyze_And_Resolve (I);
16461 -- If expander is inactive, type is legal, nothing else to construct
16468 if not Is_Discrete_Type (T) then
16469 Error_Msg_N ("discrete type required for range", I);
16470 Set_Etype (I, Any_Type);
16473 elsif T = Any_Type then
16474 Set_Etype (I, Any_Type);
16478 -- We will now create the appropriate Itype to describe the range, but
16479 -- first a check. If we originally had a subtype, then we just label
16480 -- the range with this subtype. Not only is there no need to construct
16481 -- a new subtype, but it is wrong to do so for two reasons:
16483 -- 1. A legality concern, if we have a subtype, it must not freeze,
16484 -- and the Itype would cause freezing incorrectly
16486 -- 2. An efficiency concern, if we created an Itype, it would not be
16487 -- recognized as the same type for the purposes of eliminating
16488 -- checks in some circumstances.
16490 -- We signal this case by setting the subtype entity in Def_Id
16492 if No (Def_Id) then
16494 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16495 Set_Etype (Def_Id, Base_Type (T));
16497 if Is_Signed_Integer_Type (T) then
16498 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16500 elsif Is_Modular_Integer_Type (T) then
16501 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16504 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16505 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16506 Set_First_Literal (Def_Id, First_Literal (T));
16509 Set_Size_Info (Def_Id, (T));
16510 Set_RM_Size (Def_Id, RM_Size (T));
16511 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16513 Set_Scalar_Range (Def_Id, R);
16514 Conditional_Delay (Def_Id, T);
16516 -- In the subtype indication case, if the immediate parent of the
16517 -- new subtype is non-static, then the subtype we create is non-
16518 -- static, even if its bounds are static.
16520 if Nkind (I) = N_Subtype_Indication
16521 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16523 Set_Is_Non_Static_Subtype (Def_Id);
16527 -- Final step is to label the index with this constructed type
16529 Set_Etype (I, Def_Id);
16532 ------------------------------
16533 -- Modular_Type_Declaration --
16534 ------------------------------
16536 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16537 Mod_Expr : constant Node_Id := Expression (Def);
16540 procedure Set_Modular_Size (Bits : Int);
16541 -- Sets RM_Size to Bits, and Esize to normal word size above this
16543 ----------------------
16544 -- Set_Modular_Size --
16545 ----------------------
16547 procedure Set_Modular_Size (Bits : Int) is
16549 Set_RM_Size (T, UI_From_Int (Bits));
16554 elsif Bits <= 16 then
16555 Init_Esize (T, 16);
16557 elsif Bits <= 32 then
16558 Init_Esize (T, 32);
16561 Init_Esize (T, System_Max_Binary_Modulus_Power);
16564 if not Non_Binary_Modulus (T)
16565 and then Esize (T) = RM_Size (T)
16567 Set_Is_Known_Valid (T);
16569 end Set_Modular_Size;
16571 -- Start of processing for Modular_Type_Declaration
16574 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16576 Set_Ekind (T, E_Modular_Integer_Type);
16577 Init_Alignment (T);
16578 Set_Is_Constrained (T);
16580 if not Is_OK_Static_Expression (Mod_Expr) then
16581 Flag_Non_Static_Expr
16582 ("non-static expression used for modular type bound!", Mod_Expr);
16583 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16585 M_Val := Expr_Value (Mod_Expr);
16589 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16590 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16593 Set_Modulus (T, M_Val);
16595 -- Create bounds for the modular type based on the modulus given in
16596 -- the type declaration and then analyze and resolve those bounds.
16598 Set_Scalar_Range (T,
16599 Make_Range (Sloc (Mod_Expr),
16600 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16601 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16603 -- Properly analyze the literals for the range. We do this manually
16604 -- because we can't go calling Resolve, since we are resolving these
16605 -- bounds with the type, and this type is certainly not complete yet!
16607 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16608 Set_Etype (High_Bound (Scalar_Range (T)), T);
16609 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16610 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16612 -- Loop through powers of two to find number of bits required
16614 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16618 if M_Val = 2 ** Bits then
16619 Set_Modular_Size (Bits);
16624 elsif M_Val < 2 ** Bits then
16625 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16626 Set_Non_Binary_Modulus (T);
16628 if Bits > System_Max_Nonbinary_Modulus_Power then
16629 Error_Msg_Uint_1 :=
16630 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16632 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16633 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16637 -- In the non-binary case, set size as per RM 13.3(55)
16639 Set_Modular_Size (Bits);
16646 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16647 -- so we just signal an error and set the maximum size.
16649 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16650 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16652 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16653 Init_Alignment (T);
16655 end Modular_Type_Declaration;
16657 --------------------------
16658 -- New_Concatenation_Op --
16659 --------------------------
16661 procedure New_Concatenation_Op (Typ : Entity_Id) is
16662 Loc : constant Source_Ptr := Sloc (Typ);
16665 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16666 -- Create abbreviated declaration for the formal of a predefined
16667 -- Operator 'Op' of type 'Typ'
16669 --------------------
16670 -- Make_Op_Formal --
16671 --------------------
16673 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16674 Formal : Entity_Id;
16676 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16677 Set_Etype (Formal, Typ);
16678 Set_Mechanism (Formal, Default_Mechanism);
16680 end Make_Op_Formal;
16682 -- Start of processing for New_Concatenation_Op
16685 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16687 Set_Ekind (Op, E_Operator);
16688 Set_Scope (Op, Current_Scope);
16689 Set_Etype (Op, Typ);
16690 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16691 Set_Is_Immediately_Visible (Op);
16692 Set_Is_Intrinsic_Subprogram (Op);
16693 Set_Has_Completion (Op);
16694 Append_Entity (Op, Current_Scope);
16696 Set_Name_Entity_Id (Name_Op_Concat, Op);
16698 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16699 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16700 end New_Concatenation_Op;
16702 -------------------------
16703 -- OK_For_Limited_Init --
16704 -------------------------
16706 -- ???Check all calls of this, and compare the conditions under which it's
16709 function OK_For_Limited_Init
16711 Exp : Node_Id) return Boolean
16714 return Is_CPP_Constructor_Call (Exp)
16715 or else (Ada_Version >= Ada_2005
16716 and then not Debug_Flag_Dot_L
16717 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16718 end OK_For_Limited_Init;
16720 -------------------------------
16721 -- OK_For_Limited_Init_In_05 --
16722 -------------------------------
16724 function OK_For_Limited_Init_In_05
16726 Exp : Node_Id) return Boolean
16729 -- An object of a limited interface type can be initialized with any
16730 -- expression of a nonlimited descendant type.
16732 if Is_Class_Wide_Type (Typ)
16733 and then Is_Limited_Interface (Typ)
16734 and then not Is_Limited_Type (Etype (Exp))
16739 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16740 -- case of limited aggregates (including extension aggregates), and
16741 -- function calls. The function call may have been given in prefixed
16742 -- notation, in which case the original node is an indexed component.
16743 -- If the function is parameterless, the original node was an explicit
16746 case Nkind (Original_Node (Exp)) is
16747 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16750 when N_Qualified_Expression =>
16752 OK_For_Limited_Init_In_05
16753 (Typ, Expression (Original_Node (Exp)));
16755 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16756 -- with a function call, the expander has rewritten the call into an
16757 -- N_Type_Conversion node to force displacement of the pointer to
16758 -- reference the component containing the secondary dispatch table.
16759 -- Otherwise a type conversion is not a legal context.
16760 -- A return statement for a build-in-place function returning a
16761 -- synchronized type also introduces an unchecked conversion.
16763 when N_Type_Conversion |
16764 N_Unchecked_Type_Conversion =>
16765 return not Comes_From_Source (Exp)
16767 OK_For_Limited_Init_In_05
16768 (Typ, Expression (Original_Node (Exp)));
16770 when N_Indexed_Component |
16771 N_Selected_Component |
16772 N_Explicit_Dereference =>
16773 return Nkind (Exp) = N_Function_Call;
16775 -- A use of 'Input is a function call, hence allowed. Normally the
16776 -- attribute will be changed to a call, but the attribute by itself
16777 -- can occur with -gnatc.
16779 when N_Attribute_Reference =>
16780 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16785 end OK_For_Limited_Init_In_05;
16787 -------------------------------------------
16788 -- Ordinary_Fixed_Point_Type_Declaration --
16789 -------------------------------------------
16791 procedure Ordinary_Fixed_Point_Type_Declaration
16795 Loc : constant Source_Ptr := Sloc (Def);
16796 Delta_Expr : constant Node_Id := Delta_Expression (Def);
16797 RRS : constant Node_Id := Real_Range_Specification (Def);
16798 Implicit_Base : Entity_Id;
16805 Check_Restriction (No_Fixed_Point, Def);
16807 -- Create implicit base type
16810 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
16811 Set_Etype (Implicit_Base, Implicit_Base);
16813 -- Analyze and process delta expression
16815 Analyze_And_Resolve (Delta_Expr, Any_Real);
16817 Check_Delta_Expression (Delta_Expr);
16818 Delta_Val := Expr_Value_R (Delta_Expr);
16820 Set_Delta_Value (Implicit_Base, Delta_Val);
16822 -- Compute default small from given delta, which is the largest power
16823 -- of two that does not exceed the given delta value.
16833 if Delta_Val < Ureal_1 then
16834 while Delta_Val < Tmp loop
16835 Tmp := Tmp / Ureal_2;
16836 Scale := Scale + 1;
16841 Tmp := Tmp * Ureal_2;
16842 exit when Tmp > Delta_Val;
16843 Scale := Scale - 1;
16847 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
16850 Set_Small_Value (Implicit_Base, Small_Val);
16852 -- If no range was given, set a dummy range
16854 if RRS <= Empty_Or_Error then
16855 Low_Val := -Small_Val;
16856 High_Val := Small_Val;
16858 -- Otherwise analyze and process given range
16862 Low : constant Node_Id := Low_Bound (RRS);
16863 High : constant Node_Id := High_Bound (RRS);
16866 Analyze_And_Resolve (Low, Any_Real);
16867 Analyze_And_Resolve (High, Any_Real);
16868 Check_Real_Bound (Low);
16869 Check_Real_Bound (High);
16871 -- Obtain and set the range
16873 Low_Val := Expr_Value_R (Low);
16874 High_Val := Expr_Value_R (High);
16876 if Low_Val > High_Val then
16877 Error_Msg_NE ("?fixed point type& has null range", Def, T);
16882 -- The range for both the implicit base and the declared first subtype
16883 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
16884 -- set a temporary range in place. Note that the bounds of the base
16885 -- type will be widened to be symmetrical and to fill the available
16886 -- bits when the type is frozen.
16888 -- We could do this with all discrete types, and probably should, but
16889 -- we absolutely have to do it for fixed-point, since the end-points
16890 -- of the range and the size are determined by the small value, which
16891 -- could be reset before the freeze point.
16893 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
16894 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
16896 -- Complete definition of first subtype
16898 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
16899 Set_Etype (T, Implicit_Base);
16900 Init_Size_Align (T);
16901 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16902 Set_Small_Value (T, Small_Val);
16903 Set_Delta_Value (T, Delta_Val);
16904 Set_Is_Constrained (T);
16906 end Ordinary_Fixed_Point_Type_Declaration;
16908 ----------------------------------------
16909 -- Prepare_Private_Subtype_Completion --
16910 ----------------------------------------
16912 procedure Prepare_Private_Subtype_Completion
16914 Related_Nod : Node_Id)
16916 Id_B : constant Entity_Id := Base_Type (Id);
16917 Full_B : constant Entity_Id := Full_View (Id_B);
16921 if Present (Full_B) then
16923 -- The Base_Type is already completed, we can complete the subtype
16924 -- now. We have to create a new entity with the same name, Thus we
16925 -- can't use Create_Itype.
16927 -- This is messy, should be fixed ???
16929 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
16930 Set_Is_Itype (Full);
16931 Set_Associated_Node_For_Itype (Full, Related_Nod);
16932 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
16935 -- The parent subtype may be private, but the base might not, in some
16936 -- nested instances. In that case, the subtype does not need to be
16937 -- exchanged. It would still be nice to make private subtypes and their
16938 -- bases consistent at all times ???
16940 if Is_Private_Type (Id_B) then
16941 Append_Elmt (Id, Private_Dependents (Id_B));
16944 end Prepare_Private_Subtype_Completion;
16946 ---------------------------
16947 -- Process_Discriminants --
16948 ---------------------------
16950 procedure Process_Discriminants
16952 Prev : Entity_Id := Empty)
16954 Elist : constant Elist_Id := New_Elmt_List;
16957 Discr_Number : Uint;
16958 Discr_Type : Entity_Id;
16959 Default_Present : Boolean := False;
16960 Default_Not_Present : Boolean := False;
16963 -- A composite type other than an array type can have discriminants.
16964 -- On entry, the current scope is the composite type.
16966 -- The discriminants are initially entered into the scope of the type
16967 -- via Enter_Name with the default Ekind of E_Void to prevent premature
16968 -- use, as explained at the end of this procedure.
16970 Discr := First (Discriminant_Specifications (N));
16971 while Present (Discr) loop
16972 Enter_Name (Defining_Identifier (Discr));
16974 -- For navigation purposes we add a reference to the discriminant
16975 -- in the entity for the type. If the current declaration is a
16976 -- completion, place references on the partial view. Otherwise the
16977 -- type is the current scope.
16979 if Present (Prev) then
16981 -- The references go on the partial view, if present. If the
16982 -- partial view has discriminants, the references have been
16983 -- generated already.
16985 if not Has_Discriminants (Prev) then
16986 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
16990 (Current_Scope, Defining_Identifier (Discr), 'd');
16993 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
16994 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
16996 -- Ada 2005 (AI-254)
16998 if Present (Access_To_Subprogram_Definition
16999 (Discriminant_Type (Discr)))
17000 and then Protected_Present (Access_To_Subprogram_Definition
17001 (Discriminant_Type (Discr)))
17004 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17008 Find_Type (Discriminant_Type (Discr));
17009 Discr_Type := Etype (Discriminant_Type (Discr));
17011 if Error_Posted (Discriminant_Type (Discr)) then
17012 Discr_Type := Any_Type;
17016 if Is_Access_Type (Discr_Type) then
17018 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17021 if Ada_Version < Ada_2005 then
17022 Check_Access_Discriminant_Requires_Limited
17023 (Discr, Discriminant_Type (Discr));
17026 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17028 ("(Ada 83) access discriminant not allowed", Discr);
17031 elsif not Is_Discrete_Type (Discr_Type) then
17032 Error_Msg_N ("discriminants must have a discrete or access type",
17033 Discriminant_Type (Discr));
17036 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17038 -- If a discriminant specification includes the assignment compound
17039 -- delimiter followed by an expression, the expression is the default
17040 -- expression of the discriminant; the default expression must be of
17041 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17042 -- a default expression, we do the special preanalysis, since this
17043 -- expression does not freeze (see "Handling of Default and Per-
17044 -- Object Expressions" in spec of package Sem).
17046 if Present (Expression (Discr)) then
17047 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17049 if Nkind (N) = N_Formal_Type_Declaration then
17051 ("discriminant defaults not allowed for formal type",
17052 Expression (Discr));
17054 -- Flag an error for a tagged type with defaulted discriminants,
17055 -- excluding limited tagged types when compiling for Ada 2012
17056 -- (see AI05-0214).
17058 elsif Is_Tagged_Type (Current_Scope)
17059 and then (not Is_Limited_Type (Current_Scope)
17060 or else Ada_Version < Ada_2012)
17061 and then Comes_From_Source (N)
17063 -- Note: see similar test in Check_Or_Process_Discriminants, to
17064 -- handle the (illegal) case of the completion of an untagged
17065 -- view with discriminants with defaults by a tagged full view.
17066 -- We skip the check if Discr does not come from source, to
17067 -- account for the case of an untagged derived type providing
17068 -- defaults for a renamed discriminant from a private untagged
17069 -- ancestor with a tagged full view (ACATS B460006).
17071 if Ada_Version >= Ada_2012 then
17073 ("discriminants of nonlimited tagged type cannot have"
17075 Expression (Discr));
17078 ("discriminants of tagged type cannot have defaults",
17079 Expression (Discr));
17083 Default_Present := True;
17084 Append_Elmt (Expression (Discr), Elist);
17086 -- Tag the defining identifiers for the discriminants with
17087 -- their corresponding default expressions from the tree.
17089 Set_Discriminant_Default_Value
17090 (Defining_Identifier (Discr), Expression (Discr));
17094 Default_Not_Present := True;
17097 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17098 -- Discr_Type but with the null-exclusion attribute
17100 if Ada_Version >= Ada_2005 then
17102 -- Ada 2005 (AI-231): Static checks
17104 if Can_Never_Be_Null (Discr_Type) then
17105 Null_Exclusion_Static_Checks (Discr);
17107 elsif Is_Access_Type (Discr_Type)
17108 and then Null_Exclusion_Present (Discr)
17110 -- No need to check itypes because in their case this check
17111 -- was done at their point of creation
17113 and then not Is_Itype (Discr_Type)
17115 if Can_Never_Be_Null (Discr_Type) then
17117 ("`NOT NULL` not allowed (& already excludes null)",
17122 Set_Etype (Defining_Identifier (Discr),
17123 Create_Null_Excluding_Itype
17125 Related_Nod => Discr));
17127 -- Check for improper null exclusion if the type is otherwise
17128 -- legal for a discriminant.
17130 elsif Null_Exclusion_Present (Discr)
17131 and then Is_Discrete_Type (Discr_Type)
17134 ("null exclusion can only apply to an access type", Discr);
17137 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17138 -- can't have defaults. Synchronized types, or types that are
17139 -- explicitly limited are fine, but special tests apply to derived
17140 -- types in generics: in a generic body we have to assume the
17141 -- worst, and therefore defaults are not allowed if the parent is
17142 -- a generic formal private type (see ACATS B370001).
17144 if Is_Access_Type (Discr_Type) then
17145 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17146 or else not Default_Present
17147 or else Is_Limited_Record (Current_Scope)
17148 or else Is_Concurrent_Type (Current_Scope)
17149 or else Is_Concurrent_Record_Type (Current_Scope)
17150 or else Ekind (Current_Scope) = E_Limited_Private_Type
17152 if not Is_Derived_Type (Current_Scope)
17153 or else not Is_Generic_Type (Etype (Current_Scope))
17154 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17155 or else Limited_Present
17156 (Type_Definition (Parent (Current_Scope)))
17161 Error_Msg_N ("access discriminants of nonlimited types",
17162 Expression (Discr));
17163 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17166 elsif Present (Expression (Discr)) then
17168 ("(Ada 2005) access discriminants of nonlimited types",
17169 Expression (Discr));
17170 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17178 -- An element list consisting of the default expressions of the
17179 -- discriminants is constructed in the above loop and used to set
17180 -- the Discriminant_Constraint attribute for the type. If an object
17181 -- is declared of this (record or task) type without any explicit
17182 -- discriminant constraint given, this element list will form the
17183 -- actual parameters for the corresponding initialization procedure
17186 Set_Discriminant_Constraint (Current_Scope, Elist);
17187 Set_Stored_Constraint (Current_Scope, No_Elist);
17189 -- Default expressions must be provided either for all or for none
17190 -- of the discriminants of a discriminant part. (RM 3.7.1)
17192 if Default_Present and then Default_Not_Present then
17194 ("incomplete specification of defaults for discriminants", N);
17197 -- The use of the name of a discriminant is not allowed in default
17198 -- expressions of a discriminant part if the specification of the
17199 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17201 -- To detect this, the discriminant names are entered initially with an
17202 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17203 -- attempt to use a void entity (for example in an expression that is
17204 -- type-checked) produces the error message: premature usage. Now after
17205 -- completing the semantic analysis of the discriminant part, we can set
17206 -- the Ekind of all the discriminants appropriately.
17208 Discr := First (Discriminant_Specifications (N));
17209 Discr_Number := Uint_1;
17210 while Present (Discr) loop
17211 Id := Defining_Identifier (Discr);
17212 Set_Ekind (Id, E_Discriminant);
17213 Init_Component_Location (Id);
17215 Set_Discriminant_Number (Id, Discr_Number);
17217 -- Make sure this is always set, even in illegal programs
17219 Set_Corresponding_Discriminant (Id, Empty);
17221 -- Initialize the Original_Record_Component to the entity itself.
17222 -- Inherit_Components will propagate the right value to
17223 -- discriminants in derived record types.
17225 Set_Original_Record_Component (Id, Id);
17227 -- Create the discriminal for the discriminant
17229 Build_Discriminal (Id);
17232 Discr_Number := Discr_Number + 1;
17235 Set_Has_Discriminants (Current_Scope);
17236 end Process_Discriminants;
17238 -----------------------
17239 -- Process_Full_View --
17240 -----------------------
17242 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17243 Priv_Parent : Entity_Id;
17244 Full_Parent : Entity_Id;
17245 Full_Indic : Node_Id;
17247 procedure Collect_Implemented_Interfaces
17249 Ifaces : Elist_Id);
17250 -- Ada 2005: Gather all the interfaces that Typ directly or
17251 -- inherently implements. Duplicate entries are not added to
17252 -- the list Ifaces.
17254 ------------------------------------
17255 -- Collect_Implemented_Interfaces --
17256 ------------------------------------
17258 procedure Collect_Implemented_Interfaces
17263 Iface_Elmt : Elmt_Id;
17266 -- Abstract interfaces are only associated with tagged record types
17268 if not Is_Tagged_Type (Typ)
17269 or else not Is_Record_Type (Typ)
17274 -- Recursively climb to the ancestors
17276 if Etype (Typ) /= Typ
17278 -- Protect the frontend against wrong cyclic declarations like:
17280 -- type B is new A with private;
17281 -- type C is new A with private;
17283 -- type B is new C with null record;
17284 -- type C is new B with null record;
17286 and then Etype (Typ) /= Priv_T
17287 and then Etype (Typ) /= Full_T
17289 -- Keep separate the management of private type declarations
17291 if Ekind (Typ) = E_Record_Type_With_Private then
17293 -- Handle the following erroneous case:
17294 -- type Private_Type is tagged private;
17296 -- type Private_Type is new Type_Implementing_Iface;
17298 if Present (Full_View (Typ))
17299 and then Etype (Typ) /= Full_View (Typ)
17301 if Is_Interface (Etype (Typ)) then
17302 Append_Unique_Elmt (Etype (Typ), Ifaces);
17305 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17308 -- Non-private types
17311 if Is_Interface (Etype (Typ)) then
17312 Append_Unique_Elmt (Etype (Typ), Ifaces);
17315 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17319 -- Handle entities in the list of abstract interfaces
17321 if Present (Interfaces (Typ)) then
17322 Iface_Elmt := First_Elmt (Interfaces (Typ));
17323 while Present (Iface_Elmt) loop
17324 Iface := Node (Iface_Elmt);
17326 pragma Assert (Is_Interface (Iface));
17328 if not Contain_Interface (Iface, Ifaces) then
17329 Append_Elmt (Iface, Ifaces);
17330 Collect_Implemented_Interfaces (Iface, Ifaces);
17333 Next_Elmt (Iface_Elmt);
17336 end Collect_Implemented_Interfaces;
17338 -- Start of processing for Process_Full_View
17341 -- First some sanity checks that must be done after semantic
17342 -- decoration of the full view and thus cannot be placed with other
17343 -- similar checks in Find_Type_Name
17345 if not Is_Limited_Type (Priv_T)
17346 and then (Is_Limited_Type (Full_T)
17347 or else Is_Limited_Composite (Full_T))
17350 ("completion of nonlimited type cannot be limited", Full_T);
17351 Explain_Limited_Type (Full_T, Full_T);
17353 elsif Is_Abstract_Type (Full_T)
17354 and then not Is_Abstract_Type (Priv_T)
17357 ("completion of nonabstract type cannot be abstract", Full_T);
17359 elsif Is_Tagged_Type (Priv_T)
17360 and then Is_Limited_Type (Priv_T)
17361 and then not Is_Limited_Type (Full_T)
17363 -- If pragma CPP_Class was applied to the private declaration
17364 -- propagate the limitedness to the full-view
17366 if Is_CPP_Class (Priv_T) then
17367 Set_Is_Limited_Record (Full_T);
17369 -- GNAT allow its own definition of Limited_Controlled to disobey
17370 -- this rule in order in ease the implementation. The next test is
17371 -- safe because Root_Controlled is defined in a private system child
17373 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
17374 Set_Is_Limited_Composite (Full_T);
17377 ("completion of limited tagged type must be limited", Full_T);
17380 elsif Is_Generic_Type (Priv_T) then
17381 Error_Msg_N ("generic type cannot have a completion", Full_T);
17384 -- Check that ancestor interfaces of private and full views are
17385 -- consistent. We omit this check for synchronized types because
17386 -- they are performed on the corresponding record type when frozen.
17388 if Ada_Version >= Ada_2005
17389 and then Is_Tagged_Type (Priv_T)
17390 and then Is_Tagged_Type (Full_T)
17391 and then not Is_Concurrent_Type (Full_T)
17395 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17396 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17399 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17400 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17402 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17403 -- an interface type if and only if the full type is descendant
17404 -- of the interface type (AARM 7.3 (7.3/2).
17406 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17408 if Present (Iface) then
17410 ("interface & not implemented by full type " &
17411 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17414 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17416 if Present (Iface) then
17418 ("interface & not implemented by partial view " &
17419 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17424 if Is_Tagged_Type (Priv_T)
17425 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17426 and then Is_Derived_Type (Full_T)
17428 Priv_Parent := Etype (Priv_T);
17430 -- The full view of a private extension may have been transformed
17431 -- into an unconstrained derived type declaration and a subtype
17432 -- declaration (see build_derived_record_type for details).
17434 if Nkind (N) = N_Subtype_Declaration then
17435 Full_Indic := Subtype_Indication (N);
17436 Full_Parent := Etype (Base_Type (Full_T));
17438 Full_Indic := Subtype_Indication (Type_Definition (N));
17439 Full_Parent := Etype (Full_T);
17442 -- Check that the parent type of the full type is a descendant of
17443 -- the ancestor subtype given in the private extension. If either
17444 -- entity has an Etype equal to Any_Type then we had some previous
17445 -- error situation [7.3(8)].
17447 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17450 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17451 -- any order. Therefore we don't have to check that its parent must
17452 -- be a descendant of the parent of the private type declaration.
17454 elsif Is_Interface (Priv_Parent)
17455 and then Is_Interface (Full_Parent)
17459 -- Ada 2005 (AI-251): If the parent of the private type declaration
17460 -- is an interface there is no need to check that it is an ancestor
17461 -- of the associated full type declaration. The required tests for
17462 -- this case are performed by Build_Derived_Record_Type.
17464 elsif not Is_Interface (Base_Type (Priv_Parent))
17465 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17468 ("parent of full type must descend from parent"
17469 & " of private extension", Full_Indic);
17471 -- First check a formal restriction, and then proceed with checking
17472 -- Ada rules. Since the formal restriction is not a serious error, we
17473 -- don't prevent further error detection for this check, hence the
17478 -- In formal mode, when completing a private extension the type
17479 -- named in the private part must be exactly the same as that
17480 -- named in the visible part.
17482 if Priv_Parent /= Full_Parent then
17483 Error_Msg_Name_1 := Chars (Priv_Parent);
17484 Check_SPARK_Restriction ("% expected", Full_Indic);
17487 -- Check the rules of 7.3(10): if the private extension inherits
17488 -- known discriminants, then the full type must also inherit those
17489 -- discriminants from the same (ancestor) type, and the parent
17490 -- subtype of the full type must be constrained if and only if
17491 -- the ancestor subtype of the private extension is constrained.
17493 if No (Discriminant_Specifications (Parent (Priv_T)))
17494 and then not Has_Unknown_Discriminants (Priv_T)
17495 and then Has_Discriminants (Base_Type (Priv_Parent))
17498 Priv_Indic : constant Node_Id :=
17499 Subtype_Indication (Parent (Priv_T));
17501 Priv_Constr : constant Boolean :=
17502 Is_Constrained (Priv_Parent)
17504 Nkind (Priv_Indic) = N_Subtype_Indication
17506 Is_Constrained (Entity (Priv_Indic));
17508 Full_Constr : constant Boolean :=
17509 Is_Constrained (Full_Parent)
17511 Nkind (Full_Indic) = N_Subtype_Indication
17513 Is_Constrained (Entity (Full_Indic));
17515 Priv_Discr : Entity_Id;
17516 Full_Discr : Entity_Id;
17519 Priv_Discr := First_Discriminant (Priv_Parent);
17520 Full_Discr := First_Discriminant (Full_Parent);
17521 while Present (Priv_Discr) and then Present (Full_Discr) loop
17522 if Original_Record_Component (Priv_Discr) =
17523 Original_Record_Component (Full_Discr)
17525 Corresponding_Discriminant (Priv_Discr) =
17526 Corresponding_Discriminant (Full_Discr)
17533 Next_Discriminant (Priv_Discr);
17534 Next_Discriminant (Full_Discr);
17537 if Present (Priv_Discr) or else Present (Full_Discr) then
17539 ("full view must inherit discriminants of the parent"
17540 & " type used in the private extension", Full_Indic);
17542 elsif Priv_Constr and then not Full_Constr then
17544 ("parent subtype of full type must be constrained",
17547 elsif Full_Constr and then not Priv_Constr then
17549 ("parent subtype of full type must be unconstrained",
17554 -- Check the rules of 7.3(12): if a partial view has neither
17555 -- known or unknown discriminants, then the full type
17556 -- declaration shall define a definite subtype.
17558 elsif not Has_Unknown_Discriminants (Priv_T)
17559 and then not Has_Discriminants (Priv_T)
17560 and then not Is_Constrained (Full_T)
17563 ("full view must define a constrained type if partial view"
17564 & " has no discriminants", Full_T);
17567 -- ??????? Do we implement the following properly ?????
17568 -- If the ancestor subtype of a private extension has constrained
17569 -- discriminants, then the parent subtype of the full view shall
17570 -- impose a statically matching constraint on those discriminants
17575 -- For untagged types, verify that a type without discriminants
17576 -- is not completed with an unconstrained type.
17578 if not Is_Indefinite_Subtype (Priv_T)
17579 and then Is_Indefinite_Subtype (Full_T)
17581 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17585 -- AI-419: verify that the use of "limited" is consistent
17588 Orig_Decl : constant Node_Id := Original_Node (N);
17591 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17592 and then not Limited_Present (Parent (Priv_T))
17593 and then not Synchronized_Present (Parent (Priv_T))
17594 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17596 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17597 and then Limited_Present (Type_Definition (Orig_Decl))
17600 ("full view of non-limited extension cannot be limited", N);
17604 -- Ada 2005 (AI-443): A synchronized private extension must be
17605 -- completed by a task or protected type.
17607 if Ada_Version >= Ada_2005
17608 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17609 and then Synchronized_Present (Parent (Priv_T))
17610 and then not Is_Concurrent_Type (Full_T)
17612 Error_Msg_N ("full view of synchronized extension must " &
17613 "be synchronized type", N);
17616 -- Ada 2005 AI-363: if the full view has discriminants with
17617 -- defaults, it is illegal to declare constrained access subtypes
17618 -- whose designated type is the current type. This allows objects
17619 -- of the type that are declared in the heap to be unconstrained.
17621 if not Has_Unknown_Discriminants (Priv_T)
17622 and then not Has_Discriminants (Priv_T)
17623 and then Has_Discriminants (Full_T)
17625 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17627 Set_Has_Constrained_Partial_View (Full_T);
17628 Set_Has_Constrained_Partial_View (Priv_T);
17631 -- Create a full declaration for all its subtypes recorded in
17632 -- Private_Dependents and swap them similarly to the base type. These
17633 -- are subtypes that have been define before the full declaration of
17634 -- the private type. We also swap the entry in Private_Dependents list
17635 -- so we can properly restore the private view on exit from the scope.
17638 Priv_Elmt : Elmt_Id;
17643 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17644 while Present (Priv_Elmt) loop
17645 Priv := Node (Priv_Elmt);
17647 if Ekind_In (Priv, E_Private_Subtype,
17648 E_Limited_Private_Subtype,
17649 E_Record_Subtype_With_Private)
17651 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17652 Set_Is_Itype (Full);
17653 Set_Parent (Full, Parent (Priv));
17654 Set_Associated_Node_For_Itype (Full, N);
17656 -- Now we need to complete the private subtype, but since the
17657 -- base type has already been swapped, we must also swap the
17658 -- subtypes (and thus, reverse the arguments in the call to
17659 -- Complete_Private_Subtype).
17661 Copy_And_Swap (Priv, Full);
17662 Complete_Private_Subtype (Full, Priv, Full_T, N);
17663 Replace_Elmt (Priv_Elmt, Full);
17666 Next_Elmt (Priv_Elmt);
17670 -- If the private view was tagged, copy the new primitive operations
17671 -- from the private view to the full view.
17673 if Is_Tagged_Type (Full_T) then
17675 Disp_Typ : Entity_Id;
17676 Full_List : Elist_Id;
17678 Prim_Elmt : Elmt_Id;
17679 Priv_List : Elist_Id;
17683 L : Elist_Id) return Boolean;
17684 -- Determine whether list L contains element E
17692 L : Elist_Id) return Boolean
17694 List_Elmt : Elmt_Id;
17697 List_Elmt := First_Elmt (L);
17698 while Present (List_Elmt) loop
17699 if Node (List_Elmt) = E then
17703 Next_Elmt (List_Elmt);
17709 -- Start of processing
17712 if Is_Tagged_Type (Priv_T) then
17713 Priv_List := Primitive_Operations (Priv_T);
17714 Prim_Elmt := First_Elmt (Priv_List);
17716 -- In the case of a concurrent type completing a private tagged
17717 -- type, primitives may have been declared in between the two
17718 -- views. These subprograms need to be wrapped the same way
17719 -- entries and protected procedures are handled because they
17720 -- cannot be directly shared by the two views.
17722 if Is_Concurrent_Type (Full_T) then
17724 Conc_Typ : constant Entity_Id :=
17725 Corresponding_Record_Type (Full_T);
17726 Curr_Nod : Node_Id := Parent (Conc_Typ);
17727 Wrap_Spec : Node_Id;
17730 while Present (Prim_Elmt) loop
17731 Prim := Node (Prim_Elmt);
17733 if Comes_From_Source (Prim)
17734 and then not Is_Abstract_Subprogram (Prim)
17737 Make_Subprogram_Declaration (Sloc (Prim),
17741 Obj_Typ => Conc_Typ,
17743 Parameter_Specifications (
17746 Insert_After (Curr_Nod, Wrap_Spec);
17747 Curr_Nod := Wrap_Spec;
17749 Analyze (Wrap_Spec);
17752 Next_Elmt (Prim_Elmt);
17758 -- For non-concurrent types, transfer explicit primitives, but
17759 -- omit those inherited from the parent of the private view
17760 -- since they will be re-inherited later on.
17763 Full_List := Primitive_Operations (Full_T);
17765 while Present (Prim_Elmt) loop
17766 Prim := Node (Prim_Elmt);
17768 if Comes_From_Source (Prim)
17769 and then not Contains (Prim, Full_List)
17771 Append_Elmt (Prim, Full_List);
17774 Next_Elmt (Prim_Elmt);
17778 -- Untagged private view
17781 Full_List := Primitive_Operations (Full_T);
17783 -- In this case the partial view is untagged, so here we locate
17784 -- all of the earlier primitives that need to be treated as
17785 -- dispatching (those that appear between the two views). Note
17786 -- that these additional operations must all be new operations
17787 -- (any earlier operations that override inherited operations
17788 -- of the full view will already have been inserted in the
17789 -- primitives list, marked by Check_Operation_From_Private_View
17790 -- as dispatching. Note that implicit "/=" operators are
17791 -- excluded from being added to the primitives list since they
17792 -- shouldn't be treated as dispatching (tagged "/=" is handled
17795 Prim := Next_Entity (Full_T);
17796 while Present (Prim) and then Prim /= Priv_T loop
17797 if Ekind_In (Prim, E_Procedure, E_Function) then
17798 Disp_Typ := Find_Dispatching_Type (Prim);
17800 if Disp_Typ = Full_T
17801 and then (Chars (Prim) /= Name_Op_Ne
17802 or else Comes_From_Source (Prim))
17804 Check_Controlling_Formals (Full_T, Prim);
17806 if not Is_Dispatching_Operation (Prim) then
17807 Append_Elmt (Prim, Full_List);
17808 Set_Is_Dispatching_Operation (Prim, True);
17809 Set_DT_Position (Prim, No_Uint);
17812 elsif Is_Dispatching_Operation (Prim)
17813 and then Disp_Typ /= Full_T
17816 -- Verify that it is not otherwise controlled by a
17817 -- formal or a return value of type T.
17819 Check_Controlling_Formals (Disp_Typ, Prim);
17823 Next_Entity (Prim);
17827 -- For the tagged case, the two views can share the same primitive
17828 -- operations list and the same class-wide type. Update attributes
17829 -- of the class-wide type which depend on the full declaration.
17831 if Is_Tagged_Type (Priv_T) then
17832 Set_Direct_Primitive_Operations (Priv_T, Full_List);
17833 Set_Class_Wide_Type
17834 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
17836 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
17841 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
17843 if Known_To_Have_Preelab_Init (Priv_T) then
17845 -- Case where there is a pragma Preelaborable_Initialization. We
17846 -- always allow this in predefined units, which is a bit of a kludge,
17847 -- but it means we don't have to struggle to meet the requirements in
17848 -- the RM for having Preelaborable Initialization. Otherwise we
17849 -- require that the type meets the RM rules. But we can't check that
17850 -- yet, because of the rule about overriding Initialize, so we simply
17851 -- set a flag that will be checked at freeze time.
17853 if not In_Predefined_Unit (Full_T) then
17854 Set_Must_Have_Preelab_Init (Full_T);
17858 -- If pragma CPP_Class was applied to the private type declaration,
17859 -- propagate it now to the full type declaration.
17861 if Is_CPP_Class (Priv_T) then
17862 Set_Is_CPP_Class (Full_T);
17863 Set_Convention (Full_T, Convention_CPP);
17866 -- If the private view has user specified stream attributes, then so has
17869 -- Why the test, how could these flags be already set in Full_T ???
17871 if Has_Specified_Stream_Read (Priv_T) then
17872 Set_Has_Specified_Stream_Read (Full_T);
17875 if Has_Specified_Stream_Write (Priv_T) then
17876 Set_Has_Specified_Stream_Write (Full_T);
17879 if Has_Specified_Stream_Input (Priv_T) then
17880 Set_Has_Specified_Stream_Input (Full_T);
17883 if Has_Specified_Stream_Output (Priv_T) then
17884 Set_Has_Specified_Stream_Output (Full_T);
17887 -- Propagate invariants to full type
17889 if Has_Invariants (Priv_T) then
17890 Set_Has_Invariants (Full_T);
17891 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
17894 if Has_Inheritable_Invariants (Priv_T) then
17895 Set_Has_Inheritable_Invariants (Full_T);
17898 -- Propagate predicates to full type
17900 if Has_Predicates (Priv_T) then
17901 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
17902 Set_Has_Predicates (Priv_T);
17904 end Process_Full_View;
17906 -----------------------------------
17907 -- Process_Incomplete_Dependents --
17908 -----------------------------------
17910 procedure Process_Incomplete_Dependents
17912 Full_T : Entity_Id;
17915 Inc_Elmt : Elmt_Id;
17916 Priv_Dep : Entity_Id;
17917 New_Subt : Entity_Id;
17919 Disc_Constraint : Elist_Id;
17922 if No (Private_Dependents (Inc_T)) then
17926 -- Itypes that may be generated by the completion of an incomplete
17927 -- subtype are not used by the back-end and not attached to the tree.
17928 -- They are created only for constraint-checking purposes.
17930 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
17931 while Present (Inc_Elmt) loop
17932 Priv_Dep := Node (Inc_Elmt);
17934 if Ekind (Priv_Dep) = E_Subprogram_Type then
17936 -- An Access_To_Subprogram type may have a return type or a
17937 -- parameter type that is incomplete. Replace with the full view.
17939 if Etype (Priv_Dep) = Inc_T then
17940 Set_Etype (Priv_Dep, Full_T);
17944 Formal : Entity_Id;
17947 Formal := First_Formal (Priv_Dep);
17948 while Present (Formal) loop
17949 if Etype (Formal) = Inc_T then
17950 Set_Etype (Formal, Full_T);
17953 Next_Formal (Formal);
17957 elsif Is_Overloadable (Priv_Dep) then
17959 -- If a subprogram in the incomplete dependents list is primitive
17960 -- for a tagged full type then mark it as a dispatching operation,
17961 -- check whether it overrides an inherited subprogram, and check
17962 -- restrictions on its controlling formals. Note that a protected
17963 -- operation is never dispatching: only its wrapper operation
17964 -- (which has convention Ada) is.
17966 if Is_Tagged_Type (Full_T)
17967 and then Is_Primitive (Priv_Dep)
17968 and then Convention (Priv_Dep) /= Convention_Protected
17970 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
17971 Set_Is_Dispatching_Operation (Priv_Dep);
17972 Check_Controlling_Formals (Full_T, Priv_Dep);
17975 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
17977 -- Can happen during processing of a body before the completion
17978 -- of a TA type. Ignore, because spec is also on dependent list.
17982 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
17983 -- corresponding subtype of the full view.
17985 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
17986 Set_Subtype_Indication
17987 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
17988 Set_Etype (Priv_Dep, Full_T);
17989 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
17990 Set_Analyzed (Parent (Priv_Dep), False);
17992 -- Reanalyze the declaration, suppressing the call to
17993 -- Enter_Name to avoid duplicate names.
17995 Analyze_Subtype_Declaration
17996 (N => Parent (Priv_Dep),
17999 -- Dependent is a subtype
18002 -- We build a new subtype indication using the full view of the
18003 -- incomplete parent. The discriminant constraints have been
18004 -- elaborated already at the point of the subtype declaration.
18006 New_Subt := Create_Itype (E_Void, N);
18008 if Has_Discriminants (Full_T) then
18009 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18011 Disc_Constraint := No_Elist;
18014 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18015 Set_Full_View (Priv_Dep, New_Subt);
18018 Next_Elmt (Inc_Elmt);
18020 end Process_Incomplete_Dependents;
18022 --------------------------------
18023 -- Process_Range_Expr_In_Decl --
18024 --------------------------------
18026 procedure Process_Range_Expr_In_Decl
18029 Check_List : List_Id := Empty_List;
18030 R_Check_Off : Boolean := False;
18031 In_Iter_Schm : Boolean := False)
18034 R_Checks : Check_Result;
18035 Insert_Node : Node_Id;
18036 Def_Id : Entity_Id;
18039 Analyze_And_Resolve (R, Base_Type (T));
18041 if Nkind (R) = N_Range then
18043 -- In SPARK, all ranges should be static, with the exception of the
18044 -- discrete type definition of a loop parameter specification.
18046 if not In_Iter_Schm
18047 and then not Is_Static_Range (R)
18049 Check_SPARK_Restriction ("range should be static", R);
18052 Lo := Low_Bound (R);
18053 Hi := High_Bound (R);
18055 -- We need to ensure validity of the bounds here, because if we
18056 -- go ahead and do the expansion, then the expanded code will get
18057 -- analyzed with range checks suppressed and we miss the check.
18059 Validity_Check_Range (R);
18061 -- If there were errors in the declaration, try and patch up some
18062 -- common mistakes in the bounds. The cases handled are literals
18063 -- which are Integer where the expected type is Real and vice versa.
18064 -- These corrections allow the compilation process to proceed further
18065 -- along since some basic assumptions of the format of the bounds
18068 if Etype (R) = Any_Type then
18070 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18072 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18074 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18076 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18078 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18080 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18082 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18084 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18091 -- If the bounds of the range have been mistakenly given as string
18092 -- literals (perhaps in place of character literals), then an error
18093 -- has already been reported, but we rewrite the string literal as a
18094 -- bound of the range's type to avoid blowups in later processing
18095 -- that looks at static values.
18097 if Nkind (Lo) = N_String_Literal then
18099 Make_Attribute_Reference (Sloc (Lo),
18100 Attribute_Name => Name_First,
18101 Prefix => New_Reference_To (T, Sloc (Lo))));
18102 Analyze_And_Resolve (Lo);
18105 if Nkind (Hi) = N_String_Literal then
18107 Make_Attribute_Reference (Sloc (Hi),
18108 Attribute_Name => Name_First,
18109 Prefix => New_Reference_To (T, Sloc (Hi))));
18110 Analyze_And_Resolve (Hi);
18113 -- If bounds aren't scalar at this point then exit, avoiding
18114 -- problems with further processing of the range in this procedure.
18116 if not Is_Scalar_Type (Etype (Lo)) then
18120 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18121 -- then range of the base type. Here we check whether the bounds
18122 -- are in the range of the subtype itself. Note that if the bounds
18123 -- represent the null range the Constraint_Error exception should
18126 -- ??? The following code should be cleaned up as follows
18128 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18129 -- is done in the call to Range_Check (R, T); below
18131 -- 2. The use of R_Check_Off should be investigated and possibly
18132 -- removed, this would clean up things a bit.
18134 if Is_Null_Range (Lo, Hi) then
18138 -- Capture values of bounds and generate temporaries for them
18139 -- if needed, before applying checks, since checks may cause
18140 -- duplication of the expression without forcing evaluation.
18142 if Expander_Active then
18143 Force_Evaluation (Lo);
18144 Force_Evaluation (Hi);
18147 -- We use a flag here instead of suppressing checks on the
18148 -- type because the type we check against isn't necessarily
18149 -- the place where we put the check.
18151 if not R_Check_Off then
18152 R_Checks := Get_Range_Checks (R, T);
18154 -- Look up tree to find an appropriate insertion point. We
18155 -- can't just use insert_actions because later processing
18156 -- depends on the insertion node. Prior to Ada2012 the
18157 -- insertion point could only be a declaration or a loop, but
18158 -- quantified expressions can appear within any context in an
18159 -- expression, and the insertion point can be any statement,
18160 -- pragma, or declaration.
18162 Insert_Node := Parent (R);
18163 while Present (Insert_Node) loop
18165 Nkind (Insert_Node) in N_Declaration
18168 (Insert_Node, N_Component_Declaration,
18169 N_Loop_Parameter_Specification,
18170 N_Function_Specification,
18171 N_Procedure_Specification);
18173 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18174 or else Nkind (Insert_Node) in
18175 N_Statement_Other_Than_Procedure_Call
18176 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18179 Insert_Node := Parent (Insert_Node);
18182 -- Why would Type_Decl not be present??? Without this test,
18183 -- short regression tests fail.
18185 if Present (Insert_Node) then
18187 -- Case of loop statement. Verify that the range is part
18188 -- of the subtype indication of the iteration scheme.
18190 if Nkind (Insert_Node) = N_Loop_Statement then
18195 Indic := Parent (R);
18196 while Present (Indic)
18197 and then Nkind (Indic) /= N_Subtype_Indication
18199 Indic := Parent (Indic);
18202 if Present (Indic) then
18203 Def_Id := Etype (Subtype_Mark (Indic));
18205 Insert_Range_Checks
18209 Sloc (Insert_Node),
18211 Do_Before => True);
18215 -- Insertion before a declaration. If the declaration
18216 -- includes discriminants, the list of applicable checks
18217 -- is given by the caller.
18219 elsif Nkind (Insert_Node) in N_Declaration then
18220 Def_Id := Defining_Identifier (Insert_Node);
18222 if (Ekind (Def_Id) = E_Record_Type
18223 and then Depends_On_Discriminant (R))
18225 (Ekind (Def_Id) = E_Protected_Type
18226 and then Has_Discriminants (Def_Id))
18228 Append_Range_Checks
18230 Check_List, Def_Id, Sloc (Insert_Node), R);
18233 Insert_Range_Checks
18235 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18239 -- Insertion before a statement. Range appears in the
18240 -- context of a quantified expression. Insertion will
18241 -- take place when expression is expanded.
18250 -- Case of other than an explicit N_Range node
18252 elsif Expander_Active then
18253 Get_Index_Bounds (R, Lo, Hi);
18254 Force_Evaluation (Lo);
18255 Force_Evaluation (Hi);
18257 end Process_Range_Expr_In_Decl;
18259 --------------------------------------
18260 -- Process_Real_Range_Specification --
18261 --------------------------------------
18263 procedure Process_Real_Range_Specification (Def : Node_Id) is
18264 Spec : constant Node_Id := Real_Range_Specification (Def);
18267 Err : Boolean := False;
18269 procedure Analyze_Bound (N : Node_Id);
18270 -- Analyze and check one bound
18272 -------------------
18273 -- Analyze_Bound --
18274 -------------------
18276 procedure Analyze_Bound (N : Node_Id) is
18278 Analyze_And_Resolve (N, Any_Real);
18280 if not Is_OK_Static_Expression (N) then
18281 Flag_Non_Static_Expr
18282 ("bound in real type definition is not static!", N);
18287 -- Start of processing for Process_Real_Range_Specification
18290 if Present (Spec) then
18291 Lo := Low_Bound (Spec);
18292 Hi := High_Bound (Spec);
18293 Analyze_Bound (Lo);
18294 Analyze_Bound (Hi);
18296 -- If error, clear away junk range specification
18299 Set_Real_Range_Specification (Def, Empty);
18302 end Process_Real_Range_Specification;
18304 ---------------------
18305 -- Process_Subtype --
18306 ---------------------
18308 function Process_Subtype
18310 Related_Nod : Node_Id;
18311 Related_Id : Entity_Id := Empty;
18312 Suffix : Character := ' ') return Entity_Id
18315 Def_Id : Entity_Id;
18316 Error_Node : Node_Id;
18317 Full_View_Id : Entity_Id;
18318 Subtype_Mark_Id : Entity_Id;
18320 May_Have_Null_Exclusion : Boolean;
18322 procedure Check_Incomplete (T : Entity_Id);
18323 -- Called to verify that an incomplete type is not used prematurely
18325 ----------------------
18326 -- Check_Incomplete --
18327 ----------------------
18329 procedure Check_Incomplete (T : Entity_Id) is
18331 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18333 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18335 not (Ada_Version >= Ada_2005
18337 (Nkind (Parent (T)) = N_Subtype_Declaration
18339 (Nkind (Parent (T)) = N_Subtype_Indication
18340 and then Nkind (Parent (Parent (T))) =
18341 N_Subtype_Declaration)))
18343 Error_Msg_N ("invalid use of type before its full declaration", T);
18345 end Check_Incomplete;
18347 -- Start of processing for Process_Subtype
18350 -- Case of no constraints present
18352 if Nkind (S) /= N_Subtype_Indication then
18354 Check_Incomplete (S);
18357 -- Ada 2005 (AI-231): Static check
18359 if Ada_Version >= Ada_2005
18360 and then Present (P)
18361 and then Null_Exclusion_Present (P)
18362 and then Nkind (P) /= N_Access_To_Object_Definition
18363 and then not Is_Access_Type (Entity (S))
18365 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18368 -- The following is ugly, can't we have a range or even a flag???
18370 May_Have_Null_Exclusion :=
18371 Nkind_In (P, N_Access_Definition,
18372 N_Access_Function_Definition,
18373 N_Access_Procedure_Definition,
18374 N_Access_To_Object_Definition,
18376 N_Component_Definition)
18378 Nkind_In (P, N_Derived_Type_Definition,
18379 N_Discriminant_Specification,
18380 N_Formal_Object_Declaration,
18381 N_Object_Declaration,
18382 N_Object_Renaming_Declaration,
18383 N_Parameter_Specification,
18384 N_Subtype_Declaration);
18386 -- Create an Itype that is a duplicate of Entity (S) but with the
18387 -- null-exclusion attribute.
18389 if May_Have_Null_Exclusion
18390 and then Is_Access_Type (Entity (S))
18391 and then Null_Exclusion_Present (P)
18393 -- No need to check the case of an access to object definition.
18394 -- It is correct to define double not-null pointers.
18397 -- type Not_Null_Int_Ptr is not null access Integer;
18398 -- type Acc is not null access Not_Null_Int_Ptr;
18400 and then Nkind (P) /= N_Access_To_Object_Definition
18402 if Can_Never_Be_Null (Entity (S)) then
18403 case Nkind (Related_Nod) is
18404 when N_Full_Type_Declaration =>
18405 if Nkind (Type_Definition (Related_Nod))
18406 in N_Array_Type_Definition
18410 (Component_Definition
18411 (Type_Definition (Related_Nod)));
18414 Subtype_Indication (Type_Definition (Related_Nod));
18417 when N_Subtype_Declaration =>
18418 Error_Node := Subtype_Indication (Related_Nod);
18420 when N_Object_Declaration =>
18421 Error_Node := Object_Definition (Related_Nod);
18423 when N_Component_Declaration =>
18425 Subtype_Indication (Component_Definition (Related_Nod));
18427 when N_Allocator =>
18428 Error_Node := Expression (Related_Nod);
18431 pragma Assert (False);
18432 Error_Node := Related_Nod;
18436 ("`NOT NULL` not allowed (& already excludes null)",
18442 Create_Null_Excluding_Itype
18444 Related_Nod => P));
18445 Set_Entity (S, Etype (S));
18450 -- Case of constraint present, so that we have an N_Subtype_Indication
18451 -- node (this node is created only if constraints are present).
18454 Find_Type (Subtype_Mark (S));
18456 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18458 (Nkind (Parent (S)) = N_Subtype_Declaration
18459 and then Is_Itype (Defining_Identifier (Parent (S))))
18461 Check_Incomplete (Subtype_Mark (S));
18465 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18467 -- Explicit subtype declaration case
18469 if Nkind (P) = N_Subtype_Declaration then
18470 Def_Id := Defining_Identifier (P);
18472 -- Explicit derived type definition case
18474 elsif Nkind (P) = N_Derived_Type_Definition then
18475 Def_Id := Defining_Identifier (Parent (P));
18477 -- Implicit case, the Def_Id must be created as an implicit type.
18478 -- The one exception arises in the case of concurrent types, array
18479 -- and access types, where other subsidiary implicit types may be
18480 -- created and must appear before the main implicit type. In these
18481 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18482 -- has not yet been called to create Def_Id.
18485 if Is_Array_Type (Subtype_Mark_Id)
18486 or else Is_Concurrent_Type (Subtype_Mark_Id)
18487 or else Is_Access_Type (Subtype_Mark_Id)
18491 -- For the other cases, we create a new unattached Itype,
18492 -- and set the indication to ensure it gets attached later.
18496 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18500 -- If the kind of constraint is invalid for this kind of type,
18501 -- then give an error, and then pretend no constraint was given.
18503 if not Is_Valid_Constraint_Kind
18504 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18507 ("incorrect constraint for this kind of type", Constraint (S));
18509 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18511 -- Set Ekind of orphan itype, to prevent cascaded errors
18513 if Present (Def_Id) then
18514 Set_Ekind (Def_Id, Ekind (Any_Type));
18517 -- Make recursive call, having got rid of the bogus constraint
18519 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18522 -- Remaining processing depends on type
18524 case Ekind (Subtype_Mark_Id) is
18525 when Access_Kind =>
18526 Constrain_Access (Def_Id, S, Related_Nod);
18529 and then Is_Itype (Designated_Type (Def_Id))
18530 and then Nkind (Related_Nod) = N_Subtype_Declaration
18531 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18533 Build_Itype_Reference
18534 (Designated_Type (Def_Id), Related_Nod);
18538 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18540 when Decimal_Fixed_Point_Kind =>
18541 Constrain_Decimal (Def_Id, S);
18543 when Enumeration_Kind =>
18544 Constrain_Enumeration (Def_Id, S);
18546 when Ordinary_Fixed_Point_Kind =>
18547 Constrain_Ordinary_Fixed (Def_Id, S);
18550 Constrain_Float (Def_Id, S);
18552 when Integer_Kind =>
18553 Constrain_Integer (Def_Id, S);
18555 when E_Record_Type |
18558 E_Incomplete_Type =>
18559 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18561 if Ekind (Def_Id) = E_Incomplete_Type then
18562 Set_Private_Dependents (Def_Id, New_Elmt_List);
18565 when Private_Kind =>
18566 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18567 Set_Private_Dependents (Def_Id, New_Elmt_List);
18569 -- In case of an invalid constraint prevent further processing
18570 -- since the type constructed is missing expected fields.
18572 if Etype (Def_Id) = Any_Type then
18576 -- If the full view is that of a task with discriminants,
18577 -- we must constrain both the concurrent type and its
18578 -- corresponding record type. Otherwise we will just propagate
18579 -- the constraint to the full view, if available.
18581 if Present (Full_View (Subtype_Mark_Id))
18582 and then Has_Discriminants (Subtype_Mark_Id)
18583 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18586 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18588 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18589 Constrain_Concurrent (Full_View_Id, S,
18590 Related_Nod, Related_Id, Suffix);
18591 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18592 Set_Full_View (Def_Id, Full_View_Id);
18594 -- Introduce an explicit reference to the private subtype,
18595 -- to prevent scope anomalies in gigi if first use appears
18596 -- in a nested context, e.g. a later function body.
18597 -- Should this be generated in other contexts than a full
18598 -- type declaration?
18600 if Is_Itype (Def_Id)
18602 Nkind (Parent (P)) = N_Full_Type_Declaration
18604 Build_Itype_Reference (Def_Id, Parent (P));
18608 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18611 when Concurrent_Kind =>
18612 Constrain_Concurrent (Def_Id, S,
18613 Related_Nod, Related_Id, Suffix);
18616 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18619 -- Size and Convention are always inherited from the base type
18621 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18622 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18626 end Process_Subtype;
18628 ---------------------------------------
18629 -- Check_Anonymous_Access_Components --
18630 ---------------------------------------
18632 procedure Check_Anonymous_Access_Components
18633 (Typ_Decl : Node_Id;
18636 Comp_List : Node_Id)
18638 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18639 Anon_Access : Entity_Id;
18642 Comp_Def : Node_Id;
18644 Type_Def : Node_Id;
18646 procedure Build_Incomplete_Type_Declaration;
18647 -- If the record type contains components that include an access to the
18648 -- current record, then create an incomplete type declaration for the
18649 -- record, to be used as the designated type of the anonymous access.
18650 -- This is done only once, and only if there is no previous partial
18651 -- view of the type.
18653 function Designates_T (Subt : Node_Id) return Boolean;
18654 -- Check whether a node designates the enclosing record type, or 'Class
18657 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18658 -- Check whether an access definition includes a reference to
18659 -- the enclosing record type. The reference can be a subtype mark
18660 -- in the access definition itself, a 'Class attribute reference, or
18661 -- recursively a reference appearing in a parameter specification
18662 -- or result definition of an access_to_subprogram definition.
18664 --------------------------------------
18665 -- Build_Incomplete_Type_Declaration --
18666 --------------------------------------
18668 procedure Build_Incomplete_Type_Declaration is
18673 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18674 -- it's "is new ... with record" or else "is tagged record ...".
18676 Is_Tagged : constant Boolean :=
18677 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18680 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18682 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18683 and then Tagged_Present (Type_Definition (Typ_Decl)));
18686 -- If there is a previous partial view, no need to create a new one
18687 -- If the partial view, given by Prev, is incomplete, If Prev is
18688 -- a private declaration, full declaration is flagged accordingly.
18690 if Prev /= Typ then
18692 Make_Class_Wide_Type (Prev);
18693 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18694 Set_Etype (Class_Wide_Type (Typ), Typ);
18699 elsif Has_Private_Declaration (Typ) then
18701 -- If we refer to T'Class inside T, and T is the completion of a
18702 -- private type, then we need to make sure the class-wide type
18706 Make_Class_Wide_Type (Typ);
18711 -- If there was a previous anonymous access type, the incomplete
18712 -- type declaration will have been created already.
18714 elsif Present (Current_Entity (Typ))
18715 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18716 and then Full_View (Current_Entity (Typ)) = Typ
18719 and then Comes_From_Source (Current_Entity (Typ))
18720 and then not Is_Tagged_Type (Current_Entity (Typ))
18722 Make_Class_Wide_Type (Typ);
18724 ("incomplete view of tagged type should be declared tagged?",
18725 Parent (Current_Entity (Typ)));
18730 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18731 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18733 -- Type has already been inserted into the current scope. Remove
18734 -- it, and add incomplete declaration for type, so that subsequent
18735 -- anonymous access types can use it. The entity is unchained from
18736 -- the homonym list and from immediate visibility. After analysis,
18737 -- the entity in the incomplete declaration becomes immediately
18738 -- visible in the record declaration that follows.
18740 H := Current_Entity (Typ);
18743 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18746 and then Homonym (H) /= Typ
18748 H := Homonym (Typ);
18751 Set_Homonym (H, Homonym (Typ));
18754 Insert_Before (Typ_Decl, Decl);
18756 Set_Full_View (Inc_T, Typ);
18760 -- Create a common class-wide type for both views, and set the
18761 -- Etype of the class-wide type to the full view.
18763 Make_Class_Wide_Type (Inc_T);
18764 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
18765 Set_Etype (Class_Wide_Type (Typ), Typ);
18768 end Build_Incomplete_Type_Declaration;
18774 function Designates_T (Subt : Node_Id) return Boolean is
18775 Type_Id : constant Name_Id := Chars (Typ);
18777 function Names_T (Nam : Node_Id) return Boolean;
18778 -- The record type has not been introduced in the current scope
18779 -- yet, so we must examine the name of the type itself, either
18780 -- an identifier T, or an expanded name of the form P.T, where
18781 -- P denotes the current scope.
18787 function Names_T (Nam : Node_Id) return Boolean is
18789 if Nkind (Nam) = N_Identifier then
18790 return Chars (Nam) = Type_Id;
18792 elsif Nkind (Nam) = N_Selected_Component then
18793 if Chars (Selector_Name (Nam)) = Type_Id then
18794 if Nkind (Prefix (Nam)) = N_Identifier then
18795 return Chars (Prefix (Nam)) = Chars (Current_Scope);
18797 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
18798 return Chars (Selector_Name (Prefix (Nam))) =
18799 Chars (Current_Scope);
18813 -- Start of processing for Designates_T
18816 if Nkind (Subt) = N_Identifier then
18817 return Chars (Subt) = Type_Id;
18819 -- Reference can be through an expanded name which has not been
18820 -- analyzed yet, and which designates enclosing scopes.
18822 elsif Nkind (Subt) = N_Selected_Component then
18823 if Names_T (Subt) then
18826 -- Otherwise it must denote an entity that is already visible.
18827 -- The access definition may name a subtype of the enclosing
18828 -- type, if there is a previous incomplete declaration for it.
18831 Find_Selected_Component (Subt);
18833 Is_Entity_Name (Subt)
18834 and then Scope (Entity (Subt)) = Current_Scope
18836 (Chars (Base_Type (Entity (Subt))) = Type_Id
18838 (Is_Class_Wide_Type (Entity (Subt))
18840 Chars (Etype (Base_Type (Entity (Subt)))) =
18844 -- A reference to the current type may appear as the prefix of
18845 -- a 'Class attribute.
18847 elsif Nkind (Subt) = N_Attribute_Reference
18848 and then Attribute_Name (Subt) = Name_Class
18850 return Names_T (Prefix (Subt));
18861 function Mentions_T (Acc_Def : Node_Id) return Boolean is
18862 Param_Spec : Node_Id;
18864 Acc_Subprg : constant Node_Id :=
18865 Access_To_Subprogram_Definition (Acc_Def);
18868 if No (Acc_Subprg) then
18869 return Designates_T (Subtype_Mark (Acc_Def));
18872 -- Component is an access_to_subprogram: examine its formals,
18873 -- and result definition in the case of an access_to_function.
18875 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
18876 while Present (Param_Spec) loop
18877 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
18878 and then Mentions_T (Parameter_Type (Param_Spec))
18882 elsif Designates_T (Parameter_Type (Param_Spec)) then
18889 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
18890 if Nkind (Result_Definition (Acc_Subprg)) =
18891 N_Access_Definition
18893 return Mentions_T (Result_Definition (Acc_Subprg));
18895 return Designates_T (Result_Definition (Acc_Subprg));
18902 -- Start of processing for Check_Anonymous_Access_Components
18905 if No (Comp_List) then
18909 Comp := First (Component_Items (Comp_List));
18910 while Present (Comp) loop
18911 if Nkind (Comp) = N_Component_Declaration
18913 (Access_Definition (Component_Definition (Comp)))
18915 Mentions_T (Access_Definition (Component_Definition (Comp)))
18917 Comp_Def := Component_Definition (Comp);
18919 Access_To_Subprogram_Definition
18920 (Access_Definition (Comp_Def));
18922 Build_Incomplete_Type_Declaration;
18923 Anon_Access := Make_Temporary (Loc, 'S');
18925 -- Create a declaration for the anonymous access type: either
18926 -- an access_to_object or an access_to_subprogram.
18928 if Present (Acc_Def) then
18929 if Nkind (Acc_Def) = N_Access_Function_Definition then
18931 Make_Access_Function_Definition (Loc,
18932 Parameter_Specifications =>
18933 Parameter_Specifications (Acc_Def),
18934 Result_Definition => Result_Definition (Acc_Def));
18937 Make_Access_Procedure_Definition (Loc,
18938 Parameter_Specifications =>
18939 Parameter_Specifications (Acc_Def));
18944 Make_Access_To_Object_Definition (Loc,
18945 Subtype_Indication =>
18948 (Access_Definition (Comp_Def))));
18950 Set_Constant_Present
18951 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
18953 (Type_Def, All_Present (Access_Definition (Comp_Def)));
18956 Set_Null_Exclusion_Present
18958 Null_Exclusion_Present (Access_Definition (Comp_Def)));
18961 Make_Full_Type_Declaration (Loc,
18962 Defining_Identifier => Anon_Access,
18963 Type_Definition => Type_Def);
18965 Insert_Before (Typ_Decl, Decl);
18968 -- If an access to subprogram, create the extra formals
18970 if Present (Acc_Def) then
18971 Create_Extra_Formals (Designated_Type (Anon_Access));
18973 -- If an access to object, preserve entity of designated type,
18974 -- for ASIS use, before rewriting the component definition.
18981 Desig := Entity (Subtype_Indication (Type_Def));
18983 -- If the access definition is to the current record,
18984 -- the visible entity at this point is an incomplete
18985 -- type. Retrieve the full view to simplify ASIS queries
18987 if Ekind (Desig) = E_Incomplete_Type then
18988 Desig := Full_View (Desig);
18992 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
18997 Make_Component_Definition (Loc,
18998 Subtype_Indication =>
18999 New_Occurrence_Of (Anon_Access, Loc)));
19001 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19002 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19004 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19007 Set_Is_Local_Anonymous_Access (Anon_Access);
19013 if Present (Variant_Part (Comp_List)) then
19017 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19018 while Present (V) loop
19019 Check_Anonymous_Access_Components
19020 (Typ_Decl, Typ, Prev, Component_List (V));
19021 Next_Non_Pragma (V);
19025 end Check_Anonymous_Access_Components;
19027 --------------------------------
19028 -- Preanalyze_Spec_Expression --
19029 --------------------------------
19031 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19032 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19034 In_Spec_Expression := True;
19035 Preanalyze_And_Resolve (N, T);
19036 In_Spec_Expression := Save_In_Spec_Expression;
19037 end Preanalyze_Spec_Expression;
19039 -----------------------------
19040 -- Record_Type_Declaration --
19041 -----------------------------
19043 procedure Record_Type_Declaration
19048 Def : constant Node_Id := Type_Definition (N);
19049 Is_Tagged : Boolean;
19050 Tag_Comp : Entity_Id;
19053 -- These flags must be initialized before calling Process_Discriminants
19054 -- because this routine makes use of them.
19056 Set_Ekind (T, E_Record_Type);
19058 Init_Size_Align (T);
19059 Set_Interfaces (T, No_Elist);
19060 Set_Stored_Constraint (T, No_Elist);
19064 if Ada_Version < Ada_2005
19065 or else not Interface_Present (Def)
19067 if Limited_Present (Def) then
19068 Check_SPARK_Restriction ("limited is not allowed", N);
19071 if Abstract_Present (Def) then
19072 Check_SPARK_Restriction ("abstract is not allowed", N);
19075 -- The flag Is_Tagged_Type might have already been set by
19076 -- Find_Type_Name if it detected an error for declaration T. This
19077 -- arises in the case of private tagged types where the full view
19078 -- omits the word tagged.
19081 Tagged_Present (Def)
19082 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19084 Set_Is_Tagged_Type (T, Is_Tagged);
19085 Set_Is_Limited_Record (T, Limited_Present (Def));
19087 -- Type is abstract if full declaration carries keyword, or if
19088 -- previous partial view did.
19090 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19091 or else Abstract_Present (Def));
19094 Check_SPARK_Restriction ("interface is not allowed", N);
19097 Analyze_Interface_Declaration (T, Def);
19099 if Present (Discriminant_Specifications (N)) then
19101 ("interface types cannot have discriminants",
19102 Defining_Identifier
19103 (First (Discriminant_Specifications (N))));
19107 -- First pass: if there are self-referential access components,
19108 -- create the required anonymous access type declarations, and if
19109 -- need be an incomplete type declaration for T itself.
19111 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19113 if Ada_Version >= Ada_2005
19114 and then Present (Interface_List (Def))
19116 Check_Interfaces (N, Def);
19119 Ifaces_List : Elist_Id;
19122 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19123 -- already in the parents.
19127 Ifaces_List => Ifaces_List,
19128 Exclude_Parents => True);
19130 Set_Interfaces (T, Ifaces_List);
19134 -- Records constitute a scope for the component declarations within.
19135 -- The scope is created prior to the processing of these declarations.
19136 -- Discriminants are processed first, so that they are visible when
19137 -- processing the other components. The Ekind of the record type itself
19138 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19140 -- Enter record scope
19144 -- If an incomplete or private type declaration was already given for
19145 -- the type, then this scope already exists, and the discriminants have
19146 -- been declared within. We must verify that the full declaration
19147 -- matches the incomplete one.
19149 Check_Or_Process_Discriminants (N, T, Prev);
19151 Set_Is_Constrained (T, not Has_Discriminants (T));
19152 Set_Has_Delayed_Freeze (T, True);
19154 -- For tagged types add a manually analyzed component corresponding
19155 -- to the component _tag, the corresponding piece of tree will be
19156 -- expanded as part of the freezing actions if it is not a CPP_Class.
19160 -- Do not add the tag unless we are in expansion mode
19162 if Expander_Active then
19163 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19164 Enter_Name (Tag_Comp);
19166 Set_Ekind (Tag_Comp, E_Component);
19167 Set_Is_Tag (Tag_Comp);
19168 Set_Is_Aliased (Tag_Comp);
19169 Set_Etype (Tag_Comp, RTE (RE_Tag));
19170 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19171 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19172 Init_Component_Location (Tag_Comp);
19174 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19175 -- implemented interfaces.
19177 if Has_Interfaces (T) then
19178 Add_Interface_Tag_Components (N, T);
19182 Make_Class_Wide_Type (T);
19183 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19186 -- We must suppress range checks when processing record components in
19187 -- the presence of discriminants, since we don't want spurious checks to
19188 -- be generated during their analysis, but Suppress_Range_Checks flags
19189 -- must be reset the after processing the record definition.
19191 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19192 -- couldn't we just use the normal range check suppression method here.
19193 -- That would seem cleaner ???
19195 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19196 Set_Kill_Range_Checks (T, True);
19197 Record_Type_Definition (Def, Prev);
19198 Set_Kill_Range_Checks (T, False);
19200 Record_Type_Definition (Def, Prev);
19203 -- Exit from record scope
19207 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19208 -- the implemented interfaces and associate them an aliased entity.
19211 and then not Is_Empty_List (Interface_List (Def))
19213 Derive_Progenitor_Subprograms (T, T);
19215 end Record_Type_Declaration;
19217 ----------------------------
19218 -- Record_Type_Definition --
19219 ----------------------------
19221 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19222 Component : Entity_Id;
19223 Ctrl_Components : Boolean := False;
19224 Final_Storage_Only : Boolean;
19228 if Ekind (Prev_T) = E_Incomplete_Type then
19229 T := Full_View (Prev_T);
19234 -- In SPARK, tagged types and type extensions may only be declared in
19235 -- the specification of library unit packages.
19237 if Present (Def) and then Is_Tagged_Type (T) then
19243 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19244 Typ := Parent (Def);
19247 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19248 Typ := Parent (Parent (Def));
19251 Ctxt := Parent (Typ);
19253 if Nkind (Ctxt) = N_Package_Body
19254 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19256 Check_SPARK_Restriction
19257 ("type should be defined in package specification", Typ);
19259 elsif Nkind (Ctxt) /= N_Package_Specification
19260 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19262 Check_SPARK_Restriction
19263 ("type should be defined in library unit package", Typ);
19268 Final_Storage_Only := not Is_Controlled (T);
19270 -- Ada 2005: check whether an explicit Limited is present in a derived
19271 -- type declaration.
19273 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19274 and then Limited_Present (Parent (Def))
19276 Set_Is_Limited_Record (T);
19279 -- If the component list of a record type is defined by the reserved
19280 -- word null and there is no discriminant part, then the record type has
19281 -- no components and all records of the type are null records (RM 3.7)
19282 -- This procedure is also called to process the extension part of a
19283 -- record extension, in which case the current scope may have inherited
19287 or else No (Component_List (Def))
19288 or else Null_Present (Component_List (Def))
19290 if not Is_Tagged_Type (T) then
19291 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19295 Analyze_Declarations (Component_Items (Component_List (Def)));
19297 if Present (Variant_Part (Component_List (Def))) then
19298 Check_SPARK_Restriction ("variant part is not allowed", Def);
19299 Analyze (Variant_Part (Component_List (Def)));
19303 -- After completing the semantic analysis of the record definition,
19304 -- record components, both new and inherited, are accessible. Set their
19305 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19306 -- whose Ekind may be void.
19308 Component := First_Entity (Current_Scope);
19309 while Present (Component) loop
19310 if Ekind (Component) = E_Void
19311 and then not Is_Itype (Component)
19313 Set_Ekind (Component, E_Component);
19314 Init_Component_Location (Component);
19317 if Has_Task (Etype (Component)) then
19321 if Ekind (Component) /= E_Component then
19324 -- Do not set Has_Controlled_Component on a class-wide equivalent
19325 -- type. See Make_CW_Equivalent_Type.
19327 elsif not Is_Class_Wide_Equivalent_Type (T)
19328 and then (Has_Controlled_Component (Etype (Component))
19329 or else (Chars (Component) /= Name_uParent
19330 and then Is_Controlled (Etype (Component))))
19332 Set_Has_Controlled_Component (T, True);
19333 Final_Storage_Only :=
19335 and then Finalize_Storage_Only (Etype (Component));
19336 Ctrl_Components := True;
19339 Next_Entity (Component);
19342 -- A Type is Finalize_Storage_Only only if all its controlled components
19345 if Ctrl_Components then
19346 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19349 -- Place reference to end record on the proper entity, which may
19350 -- be a partial view.
19352 if Present (Def) then
19353 Process_End_Label (Def, 'e', Prev_T);
19355 end Record_Type_Definition;
19357 ------------------------
19358 -- Replace_Components --
19359 ------------------------
19361 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19362 function Process (N : Node_Id) return Traverse_Result;
19368 function Process (N : Node_Id) return Traverse_Result is
19372 if Nkind (N) = N_Discriminant_Specification then
19373 Comp := First_Discriminant (Typ);
19374 while Present (Comp) loop
19375 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19376 Set_Defining_Identifier (N, Comp);
19380 Next_Discriminant (Comp);
19383 elsif Nkind (N) = N_Component_Declaration then
19384 Comp := First_Component (Typ);
19385 while Present (Comp) loop
19386 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19387 Set_Defining_Identifier (N, Comp);
19391 Next_Component (Comp);
19398 procedure Replace is new Traverse_Proc (Process);
19400 -- Start of processing for Replace_Components
19404 end Replace_Components;
19406 -------------------------------
19407 -- Set_Completion_Referenced --
19408 -------------------------------
19410 procedure Set_Completion_Referenced (E : Entity_Id) is
19412 -- If in main unit, mark entity that is a completion as referenced,
19413 -- warnings go on the partial view when needed.
19415 if In_Extended_Main_Source_Unit (E) then
19416 Set_Referenced (E);
19418 end Set_Completion_Referenced;
19420 ---------------------
19421 -- Set_Fixed_Range --
19422 ---------------------
19424 -- The range for fixed-point types is complicated by the fact that we
19425 -- do not know the exact end points at the time of the declaration. This
19426 -- is true for three reasons:
19428 -- A size clause may affect the fudging of the end-points
19429 -- A small clause may affect the values of the end-points
19430 -- We try to include the end-points if it does not affect the size
19432 -- This means that the actual end-points must be established at the point
19433 -- when the type is frozen. Meanwhile, we first narrow the range as
19434 -- permitted (so that it will fit if necessary in a small specified size),
19435 -- and then build a range subtree with these narrowed bounds.
19437 -- Set_Fixed_Range constructs the range from real literal values, and sets
19438 -- the range as the Scalar_Range of the given fixed-point type entity.
19440 -- The parent of this range is set to point to the entity so that it is
19441 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19442 -- other scalar types, which are just pointers to the range in the
19443 -- original tree, this would otherwise be an orphan).
19445 -- The tree is left unanalyzed. When the type is frozen, the processing
19446 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19447 -- analyzed, and uses this as an indication that it should complete
19448 -- work on the range (it will know the final small and size values).
19450 procedure Set_Fixed_Range
19456 S : constant Node_Id :=
19458 Low_Bound => Make_Real_Literal (Loc, Lo),
19459 High_Bound => Make_Real_Literal (Loc, Hi));
19461 Set_Scalar_Range (E, S);
19463 end Set_Fixed_Range;
19465 ----------------------------------
19466 -- Set_Scalar_Range_For_Subtype --
19467 ----------------------------------
19469 procedure Set_Scalar_Range_For_Subtype
19470 (Def_Id : Entity_Id;
19474 Kind : constant Entity_Kind := Ekind (Def_Id);
19477 -- Defend against previous error
19479 if Nkind (R) = N_Error then
19483 Set_Scalar_Range (Def_Id, R);
19485 -- We need to link the range into the tree before resolving it so
19486 -- that types that are referenced, including importantly the subtype
19487 -- itself, are properly frozen (Freeze_Expression requires that the
19488 -- expression be properly linked into the tree). Of course if it is
19489 -- already linked in, then we do not disturb the current link.
19491 if No (Parent (R)) then
19492 Set_Parent (R, Def_Id);
19495 -- Reset the kind of the subtype during analysis of the range, to
19496 -- catch possible premature use in the bounds themselves.
19498 Set_Ekind (Def_Id, E_Void);
19499 Process_Range_Expr_In_Decl (R, Subt);
19500 Set_Ekind (Def_Id, Kind);
19502 -- In ALFA, all subtypes should have a static range
19504 if Nkind (R) = N_Range
19505 and then not Is_Static_Range (R)
19507 Set_Is_In_ALFA (Def_Id, False);
19509 end Set_Scalar_Range_For_Subtype;
19511 --------------------------------------------------------
19512 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19513 --------------------------------------------------------
19515 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19519 -- Make sure set if encountered during Expand_To_Stored_Constraint
19521 Set_Stored_Constraint (E, No_Elist);
19523 -- Give it the right value
19525 if Is_Constrained (E) and then Has_Discriminants (E) then
19526 Set_Stored_Constraint (E,
19527 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19529 end Set_Stored_Constraint_From_Discriminant_Constraint;
19531 -------------------------------------
19532 -- Signed_Integer_Type_Declaration --
19533 -------------------------------------
19535 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19536 Implicit_Base : Entity_Id;
19537 Base_Typ : Entity_Id;
19540 Errs : Boolean := False;
19544 function Can_Derive_From (E : Entity_Id) return Boolean;
19545 -- Determine whether given bounds allow derivation from specified type
19547 procedure Check_Bound (Expr : Node_Id);
19548 -- Check bound to make sure it is integral and static. If not, post
19549 -- appropriate error message and set Errs flag
19551 ---------------------
19552 -- Can_Derive_From --
19553 ---------------------
19555 -- Note we check both bounds against both end values, to deal with
19556 -- strange types like ones with a range of 0 .. -12341234.
19558 function Can_Derive_From (E : Entity_Id) return Boolean is
19559 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19560 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19562 return Lo <= Lo_Val and then Lo_Val <= Hi
19564 Lo <= Hi_Val and then Hi_Val <= Hi;
19565 end Can_Derive_From;
19571 procedure Check_Bound (Expr : Node_Id) is
19573 -- If a range constraint is used as an integer type definition, each
19574 -- bound of the range must be defined by a static expression of some
19575 -- integer type, but the two bounds need not have the same integer
19576 -- type (Negative bounds are allowed.) (RM 3.5.4)
19578 if not Is_Integer_Type (Etype (Expr)) then
19580 ("integer type definition bounds must be of integer type", Expr);
19583 elsif not Is_OK_Static_Expression (Expr) then
19584 Flag_Non_Static_Expr
19585 ("non-static expression used for integer type bound!", Expr);
19588 -- The bounds are folded into literals, and we set their type to be
19589 -- universal, to avoid typing difficulties: we cannot set the type
19590 -- of the literal to the new type, because this would be a forward
19591 -- reference for the back end, and if the original type is user-
19592 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19595 if Is_Entity_Name (Expr) then
19596 Fold_Uint (Expr, Expr_Value (Expr), True);
19599 Set_Etype (Expr, Universal_Integer);
19603 -- Start of processing for Signed_Integer_Type_Declaration
19606 -- Create an anonymous base type
19609 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19611 -- Analyze and check the bounds, they can be of any integer type
19613 Lo := Low_Bound (Def);
19614 Hi := High_Bound (Def);
19616 -- Arbitrarily use Integer as the type if either bound had an error
19618 if Hi = Error or else Lo = Error then
19619 Base_Typ := Any_Integer;
19620 Set_Error_Posted (T, True);
19622 -- Here both bounds are OK expressions
19625 Analyze_And_Resolve (Lo, Any_Integer);
19626 Analyze_And_Resolve (Hi, Any_Integer);
19632 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19633 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19636 -- Find type to derive from
19638 Lo_Val := Expr_Value (Lo);
19639 Hi_Val := Expr_Value (Hi);
19641 if Can_Derive_From (Standard_Short_Short_Integer) then
19642 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19644 elsif Can_Derive_From (Standard_Short_Integer) then
19645 Base_Typ := Base_Type (Standard_Short_Integer);
19647 elsif Can_Derive_From (Standard_Integer) then
19648 Base_Typ := Base_Type (Standard_Integer);
19650 elsif Can_Derive_From (Standard_Long_Integer) then
19651 Base_Typ := Base_Type (Standard_Long_Integer);
19653 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19654 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19657 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19658 Error_Msg_N ("integer type definition bounds out of range", Def);
19659 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19660 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19664 -- Complete both implicit base and declared first subtype entities
19666 Set_Etype (Implicit_Base, Base_Typ);
19667 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19668 Set_Size_Info (Implicit_Base, (Base_Typ));
19669 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19670 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19672 Set_Ekind (T, E_Signed_Integer_Subtype);
19673 Set_Etype (T, Implicit_Base);
19675 Set_Size_Info (T, (Implicit_Base));
19676 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19677 Set_Scalar_Range (T, Def);
19678 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19679 Set_Is_Constrained (T);
19680 Set_Is_In_ALFA (T);
19681 end Signed_Integer_Type_Declaration;