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_Body;
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);
3406 -- Check No_Wide_Characters restriction
3408 Check_Wide_Character_Restriction (T, Object_Definition (N));
3410 -- Indicate this is not set in source. Certainly true for constants,
3411 -- and true for variables so far (will be reset for a variable if and
3412 -- when we encounter a modification in the source).
3414 Set_Never_Set_In_Source (Id, True);
3416 -- Now establish the proper kind and type of the object
3418 if Constant_Present (N) then
3419 Set_Ekind (Id, E_Constant);
3420 Set_Is_True_Constant (Id, True);
3423 Set_Ekind (Id, E_Variable);
3425 -- A variable is set as shared passive if it appears in a shared
3426 -- passive package, and is at the outer level. This is not done
3427 -- for entities generated during expansion, because those are
3428 -- always manipulated locally.
3430 if Is_Shared_Passive (Current_Scope)
3431 and then Is_Library_Level_Entity (Id)
3432 and then Comes_From_Source (Id)
3434 Set_Is_Shared_Passive (Id);
3435 Check_Shared_Var (Id, T, N);
3438 -- Set Has_Initial_Value if initializing expression present. Note
3439 -- that if there is no initializing expression, we leave the state
3440 -- of this flag unchanged (usually it will be False, but notably in
3441 -- the case of exception choice variables, it will already be true).
3444 Set_Has_Initial_Value (Id, True);
3448 -- Initialize alignment and size and capture alignment setting
3450 Init_Alignment (Id);
3452 Set_Optimize_Alignment_Flags (Id);
3454 -- Deal with aliased case
3456 if Aliased_Present (N) then
3457 Set_Is_Aliased (Id);
3459 -- If the object is aliased and the type is unconstrained with
3460 -- defaulted discriminants and there is no expression, then the
3461 -- object is constrained by the defaults, so it is worthwhile
3462 -- building the corresponding subtype.
3464 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3465 -- unconstrained, then only establish an actual subtype if the
3466 -- nominal subtype is indefinite. In definite cases the object is
3467 -- unconstrained in Ada 2005.
3470 and then Is_Record_Type (T)
3471 and then not Is_Constrained (T)
3472 and then Has_Discriminants (T)
3473 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3475 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3479 -- Now we can set the type of the object
3481 Set_Etype (Id, Act_T);
3483 -- Deal with controlled types
3485 if Has_Controlled_Component (Etype (Id))
3486 or else Is_Controlled (Etype (Id))
3488 if not Is_Library_Level_Entity (Id) then
3489 Check_Restriction (No_Nested_Finalization, N);
3491 Validate_Controlled_Object (Id);
3494 -- Generate a warning when an initialization causes an obvious ABE
3495 -- violation. If the init expression is a simple aggregate there
3496 -- shouldn't be any initialize/adjust call generated. This will be
3497 -- true as soon as aggregates are built in place when possible.
3499 -- ??? at the moment we do not generate warnings for temporaries
3500 -- created for those aggregates although Program_Error might be
3501 -- generated if compiled with -gnato.
3503 if Is_Controlled (Etype (Id))
3504 and then Comes_From_Source (Id)
3507 BT : constant Entity_Id := Base_Type (Etype (Id));
3509 Implicit_Call : Entity_Id;
3510 pragma Warnings (Off, Implicit_Call);
3511 -- ??? what is this for (never referenced!)
3513 function Is_Aggr (N : Node_Id) return Boolean;
3514 -- Check that N is an aggregate
3520 function Is_Aggr (N : Node_Id) return Boolean is
3522 case Nkind (Original_Node (N)) is
3523 when N_Aggregate | N_Extension_Aggregate =>
3526 when N_Qualified_Expression |
3528 N_Unchecked_Type_Conversion =>
3529 return Is_Aggr (Expression (Original_Node (N)));
3537 -- If no underlying type, we already are in an error situation.
3538 -- Do not try to add a warning since we do not have access to
3541 if No (Underlying_Type (BT)) then
3542 Implicit_Call := Empty;
3544 -- A generic type does not have usable primitive operators.
3545 -- Initialization calls are built for instances.
3547 elsif Is_Generic_Type (BT) then
3548 Implicit_Call := Empty;
3550 -- If the init expression is not an aggregate, an adjust call
3551 -- will be generated
3553 elsif Present (E) and then not Is_Aggr (E) then
3554 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3556 -- If no init expression and we are not in the deferred
3557 -- constant case, an Initialize call will be generated
3559 elsif No (E) and then not Constant_Present (N) then
3560 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3563 Implicit_Call := Empty;
3569 if Has_Task (Etype (Id)) then
3570 Check_Restriction (No_Tasking, N);
3572 -- Deal with counting max tasks
3574 -- Nothing to do if inside a generic
3576 if Inside_A_Generic then
3579 -- If library level entity, then count tasks
3581 elsif Is_Library_Level_Entity (Id) then
3582 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3584 -- If not library level entity, then indicate we don't know max
3585 -- tasks and also check task hierarchy restriction and blocking
3586 -- operation (since starting a task is definitely blocking!)
3589 Check_Restriction (Max_Tasks, N);
3590 Check_Restriction (No_Task_Hierarchy, N);
3591 Check_Potentially_Blocking_Operation (N);
3594 -- A rather specialized test. If we see two tasks being declared
3595 -- of the same type in the same object declaration, and the task
3596 -- has an entry with an address clause, we know that program error
3597 -- will be raised at run time since we can't have two tasks with
3598 -- entries at the same address.
3600 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3605 E := First_Entity (Etype (Id));
3606 while Present (E) loop
3607 if Ekind (E) = E_Entry
3608 and then Present (Get_Attribute_Definition_Clause
3609 (E, Attribute_Address))
3612 ("?more than one task with same entry address", N);
3614 ("\?Program_Error will be raised at run time", N);
3616 Make_Raise_Program_Error (Loc,
3617 Reason => PE_Duplicated_Entry_Address));
3627 -- Some simple constant-propagation: if the expression is a constant
3628 -- string initialized with a literal, share the literal. This avoids
3632 and then Is_Entity_Name (E)
3633 and then Ekind (Entity (E)) = E_Constant
3634 and then Base_Type (Etype (E)) = Standard_String
3637 Val : constant Node_Id := Constant_Value (Entity (E));
3640 and then Nkind (Val) = N_String_Literal
3642 Rewrite (E, New_Copy (Val));
3647 -- Another optimization: if the nominal subtype is unconstrained and
3648 -- the expression is a function call that returns an unconstrained
3649 -- type, rewrite the declaration as a renaming of the result of the
3650 -- call. The exceptions below are cases where the copy is expected,
3651 -- either by the back end (Aliased case) or by the semantics, as for
3652 -- initializing controlled types or copying tags for classwide types.
3655 and then Nkind (E) = N_Explicit_Dereference
3656 and then Nkind (Original_Node (E)) = N_Function_Call
3657 and then not Is_Library_Level_Entity (Id)
3658 and then not Is_Constrained (Underlying_Type (T))
3659 and then not Is_Aliased (Id)
3660 and then not Is_Class_Wide_Type (T)
3661 and then not Is_Controlled (T)
3662 and then not Has_Controlled_Component (Base_Type (T))
3663 and then Expander_Active
3666 Make_Object_Renaming_Declaration (Loc,
3667 Defining_Identifier => Id,
3668 Access_Definition => Empty,
3669 Subtype_Mark => New_Occurrence_Of
3670 (Base_Type (Etype (Id)), Loc),
3673 Set_Renamed_Object (Id, E);
3675 -- Force generation of debugging information for the constant and for
3676 -- the renamed function call.
3678 Set_Debug_Info_Needed (Id);
3679 Set_Debug_Info_Needed (Entity (Prefix (E)));
3682 if Present (Prev_Entity)
3683 and then Is_Frozen (Prev_Entity)
3684 and then not Error_Posted (Id)
3686 Error_Msg_N ("full constant declaration appears too late", N);
3689 Check_Eliminated (Id);
3691 -- Deal with setting In_Private_Part flag if in private part
3693 if Ekind (Scope (Id)) = E_Package
3694 and then In_Private_Part (Scope (Id))
3696 Set_In_Private_Part (Id);
3699 -- Check for violation of No_Local_Timing_Events
3701 if Restriction_Check_Required (No_Local_Timing_Events)
3702 and then not Is_Library_Level_Entity (Id)
3703 and then Is_RTE (Etype (Id), RE_Timing_Event)
3705 Check_Restriction (No_Local_Timing_Events, N);
3709 if Has_Aspects (N) then
3710 Analyze_Aspect_Specifications (N, Id);
3713 -- Generate 'I' xref for object initialization at definition, only used
3714 -- for the local xref section used in ALFA mode.
3716 if ALFA_Mode and then Present (Expression (Original_Node (N))) then
3717 Generate_Reference (Id, Id, 'I');
3719 end Analyze_Object_Declaration;
3721 ---------------------------
3722 -- Analyze_Others_Choice --
3723 ---------------------------
3725 -- Nothing to do for the others choice node itself, the semantic analysis
3726 -- of the others choice will occur as part of the processing of the parent
3728 procedure Analyze_Others_Choice (N : Node_Id) is
3729 pragma Warnings (Off, N);
3732 end Analyze_Others_Choice;
3734 -------------------------------------------
3735 -- Analyze_Private_Extension_Declaration --
3736 -------------------------------------------
3738 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3739 T : constant Entity_Id := Defining_Identifier (N);
3740 Indic : constant Node_Id := Subtype_Indication (N);
3741 Parent_Type : Entity_Id;
3742 Parent_Base : Entity_Id;
3745 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3747 if Is_Non_Empty_List (Interface_List (N)) then
3753 Intf := First (Interface_List (N));
3754 while Present (Intf) loop
3755 T := Find_Type_Of_Subtype_Indic (Intf);
3757 Diagnose_Interface (Intf, T);
3763 Generate_Definition (T);
3765 -- For other than Ada 2012, just enter the name in the current scope
3767 if Ada_Version < Ada_2012 then
3770 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3771 -- case of private type that completes an incomplete type.
3778 Prev := Find_Type_Name (N);
3780 pragma Assert (Prev = T
3781 or else (Ekind (Prev) = E_Incomplete_Type
3782 and then Present (Full_View (Prev))
3783 and then Full_View (Prev) = T));
3787 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3788 Parent_Base := Base_Type (Parent_Type);
3790 if Parent_Type = Any_Type
3791 or else Etype (Parent_Type) = Any_Type
3793 Set_Ekind (T, Ekind (Parent_Type));
3794 Set_Etype (T, Any_Type);
3797 elsif not Is_Tagged_Type (Parent_Type) then
3799 ("parent of type extension must be a tagged type ", Indic);
3802 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3803 Error_Msg_N ("premature derivation of incomplete type", Indic);
3806 elsif Is_Concurrent_Type (Parent_Type) then
3808 ("parent type of a private extension cannot be "
3809 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3811 Set_Etype (T, Any_Type);
3812 Set_Ekind (T, E_Limited_Private_Type);
3813 Set_Private_Dependents (T, New_Elmt_List);
3814 Set_Error_Posted (T);
3818 -- Perhaps the parent type should be changed to the class-wide type's
3819 -- specific type in this case to prevent cascading errors ???
3821 if Is_Class_Wide_Type (Parent_Type) then
3823 ("parent of type extension must not be a class-wide type", Indic);
3827 if (not Is_Package_Or_Generic_Package (Current_Scope)
3828 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3829 or else In_Private_Part (Current_Scope)
3832 Error_Msg_N ("invalid context for private extension", N);
3835 -- Set common attributes
3837 Set_Is_Pure (T, Is_Pure (Current_Scope));
3838 Set_Scope (T, Current_Scope);
3839 Set_Ekind (T, E_Record_Type_With_Private);
3840 Init_Size_Align (T);
3842 Set_Etype (T, Parent_Base);
3843 Set_Has_Task (T, Has_Task (Parent_Base));
3845 Set_Convention (T, Convention (Parent_Type));
3846 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3847 Set_Is_First_Subtype (T);
3848 Make_Class_Wide_Type (T);
3850 if Unknown_Discriminants_Present (N) then
3851 Set_Discriminant_Constraint (T, No_Elist);
3854 Build_Derived_Record_Type (N, Parent_Type, T);
3856 -- Propagate inherited invariant information. The new type has
3857 -- invariants, if the parent type has inheritable invariants,
3858 -- and these invariants can in turn be inherited.
3860 if Has_Inheritable_Invariants (Parent_Type) then
3861 Set_Has_Inheritable_Invariants (T);
3862 Set_Has_Invariants (T);
3865 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3866 -- synchronized formal derived type.
3868 if Ada_Version >= Ada_2005
3869 and then Synchronized_Present (N)
3871 Set_Is_Limited_Record (T);
3873 -- Formal derived type case
3875 if Is_Generic_Type (T) then
3877 -- The parent must be a tagged limited type or a synchronized
3880 if (not Is_Tagged_Type (Parent_Type)
3881 or else not Is_Limited_Type (Parent_Type))
3883 (not Is_Interface (Parent_Type)
3884 or else not Is_Synchronized_Interface (Parent_Type))
3886 Error_Msg_NE ("parent type of & must be tagged limited " &
3887 "or synchronized", N, T);
3890 -- The progenitors (if any) must be limited or synchronized
3893 if Present (Interfaces (T)) then
3896 Iface_Elmt : Elmt_Id;
3899 Iface_Elmt := First_Elmt (Interfaces (T));
3900 while Present (Iface_Elmt) loop
3901 Iface := Node (Iface_Elmt);
3903 if not Is_Limited_Interface (Iface)
3904 and then not Is_Synchronized_Interface (Iface)
3906 Error_Msg_NE ("progenitor & must be limited " &
3907 "or synchronized", N, Iface);
3910 Next_Elmt (Iface_Elmt);
3915 -- Regular derived extension, the parent must be a limited or
3916 -- synchronized interface.
3919 if not Is_Interface (Parent_Type)
3920 or else (not Is_Limited_Interface (Parent_Type)
3922 not Is_Synchronized_Interface (Parent_Type))
3925 ("parent type of & must be limited interface", N, T);
3929 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3930 -- extension with a synchronized parent must be explicitly declared
3931 -- synchronized, because the full view will be a synchronized type.
3932 -- This must be checked before the check for limited types below,
3933 -- to ensure that types declared limited are not allowed to extend
3934 -- synchronized interfaces.
3936 elsif Is_Interface (Parent_Type)
3937 and then Is_Synchronized_Interface (Parent_Type)
3938 and then not Synchronized_Present (N)
3941 ("private extension of& must be explicitly synchronized",
3944 elsif Limited_Present (N) then
3945 Set_Is_Limited_Record (T);
3947 if not Is_Limited_Type (Parent_Type)
3949 (not Is_Interface (Parent_Type)
3950 or else not Is_Limited_Interface (Parent_Type))
3952 Error_Msg_NE ("parent type& of limited extension must be limited",
3958 if Has_Aspects (N) then
3959 Analyze_Aspect_Specifications (N, T);
3961 end Analyze_Private_Extension_Declaration;
3963 ---------------------------------
3964 -- Analyze_Subtype_Declaration --
3965 ---------------------------------
3967 procedure Analyze_Subtype_Declaration
3969 Skip : Boolean := False)
3971 Id : constant Entity_Id := Defining_Identifier (N);
3973 R_Checks : Check_Result;
3976 Generate_Definition (Id);
3977 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3978 Init_Size_Align (Id);
3980 -- The following guard condition on Enter_Name is to handle cases where
3981 -- the defining identifier has already been entered into the scope but
3982 -- the declaration as a whole needs to be analyzed.
3984 -- This case in particular happens for derived enumeration types. The
3985 -- derived enumeration type is processed as an inserted enumeration type
3986 -- declaration followed by a rewritten subtype declaration. The defining
3987 -- identifier, however, is entered into the name scope very early in the
3988 -- processing of the original type declaration and therefore needs to be
3989 -- avoided here, when the created subtype declaration is analyzed. (See
3990 -- Build_Derived_Types)
3992 -- This also happens when the full view of a private type is derived
3993 -- type with constraints. In this case the entity has been introduced
3994 -- in the private declaration.
3997 or else (Present (Etype (Id))
3998 and then (Is_Private_Type (Etype (Id))
3999 or else Is_Task_Type (Etype (Id))
4000 or else Is_Rewrite_Substitution (N)))
4008 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4010 -- Inherit common attributes
4012 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4013 Set_Is_Volatile (Id, Is_Volatile (T));
4014 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4015 Set_Is_Atomic (Id, Is_Atomic (T));
4016 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4017 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4018 Set_Convention (Id, Convention (T));
4020 -- If ancestor has predicates then so does the subtype, and in addition
4021 -- we must delay the freeze to properly arrange predicate inheritance.
4023 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4024 -- which T = ID, so the above tests and assignments do nothing???
4026 if Has_Predicates (T)
4027 or else (Present (Ancestor_Subtype (T))
4028 and then Has_Predicates (Ancestor_Subtype (T)))
4030 Set_Has_Predicates (Id);
4031 Set_Has_Delayed_Freeze (Id);
4034 -- Subtype of Boolean cannot have a constraint in SPARK
4036 if Is_Boolean_Type (T)
4037 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4039 Check_SPARK_Restriction
4040 ("subtype of Boolean cannot have constraint", N);
4043 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4045 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4051 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4052 One_Cstr := First (Constraints (Cstr));
4053 while Present (One_Cstr) loop
4055 -- Index or discriminant constraint in SPARK must be a
4059 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4061 Check_SPARK_Restriction
4062 ("subtype mark required", One_Cstr);
4064 -- String subtype must have a lower bound of 1 in SPARK.
4065 -- Note that we do not need to test for the non-static case
4066 -- here, since that was already taken care of in
4067 -- Process_Range_Expr_In_Decl.
4069 elsif Base_Type (T) = Standard_String then
4070 Get_Index_Bounds (One_Cstr, Low, High);
4072 if Is_OK_Static_Expression (Low)
4073 and then Expr_Value (Low) /= 1
4075 Check_SPARK_Restriction
4076 ("String subtype must have lower bound of 1", N);
4086 -- In the case where there is no constraint given in the subtype
4087 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4088 -- semantic attributes must be established here.
4090 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4091 Set_Etype (Id, Base_Type (T));
4093 -- Subtype of unconstrained array without constraint is not allowed
4096 if Is_Array_Type (T)
4097 and then not Is_Constrained (T)
4099 Check_SPARK_Restriction
4100 ("subtype of unconstrained array must have constraint", N);
4105 Set_Ekind (Id, E_Array_Subtype);
4106 Copy_Array_Subtype_Attributes (Id, T);
4108 when Decimal_Fixed_Point_Kind =>
4109 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4110 Set_Digits_Value (Id, Digits_Value (T));
4111 Set_Delta_Value (Id, Delta_Value (T));
4112 Set_Scale_Value (Id, Scale_Value (T));
4113 Set_Small_Value (Id, Small_Value (T));
4114 Set_Scalar_Range (Id, Scalar_Range (T));
4115 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4116 Set_Is_Constrained (Id, Is_Constrained (T));
4117 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4118 Set_RM_Size (Id, RM_Size (T));
4120 when Enumeration_Kind =>
4121 Set_Ekind (Id, E_Enumeration_Subtype);
4122 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4123 Set_Scalar_Range (Id, Scalar_Range (T));
4124 Set_Is_Character_Type (Id, Is_Character_Type (T));
4125 Set_Is_Constrained (Id, Is_Constrained (T));
4126 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4127 Set_RM_Size (Id, RM_Size (T));
4129 when Ordinary_Fixed_Point_Kind =>
4130 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4131 Set_Scalar_Range (Id, Scalar_Range (T));
4132 Set_Small_Value (Id, Small_Value (T));
4133 Set_Delta_Value (Id, Delta_Value (T));
4134 Set_Is_Constrained (Id, Is_Constrained (T));
4135 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4136 Set_RM_Size (Id, RM_Size (T));
4139 Set_Ekind (Id, E_Floating_Point_Subtype);
4140 Set_Scalar_Range (Id, Scalar_Range (T));
4141 Set_Digits_Value (Id, Digits_Value (T));
4142 Set_Is_Constrained (Id, Is_Constrained (T));
4144 when Signed_Integer_Kind =>
4145 Set_Ekind (Id, E_Signed_Integer_Subtype);
4146 Set_Scalar_Range (Id, Scalar_Range (T));
4147 Set_Is_Constrained (Id, Is_Constrained (T));
4148 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4149 Set_RM_Size (Id, RM_Size (T));
4151 when Modular_Integer_Kind =>
4152 Set_Ekind (Id, E_Modular_Integer_Subtype);
4153 Set_Scalar_Range (Id, Scalar_Range (T));
4154 Set_Is_Constrained (Id, Is_Constrained (T));
4155 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4156 Set_RM_Size (Id, RM_Size (T));
4158 when Class_Wide_Kind =>
4159 Set_Ekind (Id, E_Class_Wide_Subtype);
4160 Set_First_Entity (Id, First_Entity (T));
4161 Set_Last_Entity (Id, Last_Entity (T));
4162 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4163 Set_Cloned_Subtype (Id, T);
4164 Set_Is_Tagged_Type (Id, True);
4165 Set_Has_Unknown_Discriminants
4168 if Ekind (T) = E_Class_Wide_Subtype then
4169 Set_Equivalent_Type (Id, Equivalent_Type (T));
4172 when E_Record_Type | E_Record_Subtype =>
4173 Set_Ekind (Id, E_Record_Subtype);
4175 if Ekind (T) = E_Record_Subtype
4176 and then Present (Cloned_Subtype (T))
4178 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4180 Set_Cloned_Subtype (Id, T);
4183 Set_First_Entity (Id, First_Entity (T));
4184 Set_Last_Entity (Id, Last_Entity (T));
4185 Set_Has_Discriminants (Id, Has_Discriminants (T));
4186 Set_Is_Constrained (Id, Is_Constrained (T));
4187 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4188 Set_Has_Unknown_Discriminants
4189 (Id, Has_Unknown_Discriminants (T));
4191 if Has_Discriminants (T) then
4192 Set_Discriminant_Constraint
4193 (Id, Discriminant_Constraint (T));
4194 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4196 elsif Has_Unknown_Discriminants (Id) then
4197 Set_Discriminant_Constraint (Id, No_Elist);
4200 if Is_Tagged_Type (T) then
4201 Set_Is_Tagged_Type (Id);
4202 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4203 Set_Direct_Primitive_Operations
4204 (Id, Direct_Primitive_Operations (T));
4205 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4207 if Is_Interface (T) then
4208 Set_Is_Interface (Id);
4209 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4213 when Private_Kind =>
4214 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4215 Set_Has_Discriminants (Id, Has_Discriminants (T));
4216 Set_Is_Constrained (Id, Is_Constrained (T));
4217 Set_First_Entity (Id, First_Entity (T));
4218 Set_Last_Entity (Id, Last_Entity (T));
4219 Set_Private_Dependents (Id, New_Elmt_List);
4220 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4221 Set_Has_Unknown_Discriminants
4222 (Id, Has_Unknown_Discriminants (T));
4223 Set_Known_To_Have_Preelab_Init
4224 (Id, Known_To_Have_Preelab_Init (T));
4226 if Is_Tagged_Type (T) then
4227 Set_Is_Tagged_Type (Id);
4228 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4229 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4230 Set_Direct_Primitive_Operations (Id,
4231 Direct_Primitive_Operations (T));
4234 -- In general the attributes of the subtype of a private type
4235 -- are the attributes of the partial view of parent. However,
4236 -- the full view may be a discriminated type, and the subtype
4237 -- must share the discriminant constraint to generate correct
4238 -- calls to initialization procedures.
4240 if Has_Discriminants (T) then
4241 Set_Discriminant_Constraint
4242 (Id, Discriminant_Constraint (T));
4243 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4245 elsif Present (Full_View (T))
4246 and then Has_Discriminants (Full_View (T))
4248 Set_Discriminant_Constraint
4249 (Id, Discriminant_Constraint (Full_View (T)));
4250 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4252 -- This would seem semantically correct, but apparently
4253 -- confuses the back-end. To be explained and checked with
4254 -- current version ???
4256 -- Set_Has_Discriminants (Id);
4259 Prepare_Private_Subtype_Completion (Id, N);
4262 Set_Ekind (Id, E_Access_Subtype);
4263 Set_Is_Constrained (Id, Is_Constrained (T));
4264 Set_Is_Access_Constant
4265 (Id, Is_Access_Constant (T));
4266 Set_Directly_Designated_Type
4267 (Id, Designated_Type (T));
4268 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4270 -- A Pure library_item must not contain the declaration of a
4271 -- named access type, except within a subprogram, generic
4272 -- subprogram, task unit, or protected unit, or if it has
4273 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4275 if Comes_From_Source (Id)
4276 and then In_Pure_Unit
4277 and then not In_Subprogram_Task_Protected_Unit
4278 and then not No_Pool_Assigned (Id)
4281 ("named access types not allowed in pure unit", N);
4284 when Concurrent_Kind =>
4285 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4286 Set_Corresponding_Record_Type (Id,
4287 Corresponding_Record_Type (T));
4288 Set_First_Entity (Id, First_Entity (T));
4289 Set_First_Private_Entity (Id, First_Private_Entity (T));
4290 Set_Has_Discriminants (Id, Has_Discriminants (T));
4291 Set_Is_Constrained (Id, Is_Constrained (T));
4292 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4293 Set_Last_Entity (Id, Last_Entity (T));
4295 if Has_Discriminants (T) then
4296 Set_Discriminant_Constraint (Id,
4297 Discriminant_Constraint (T));
4298 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4301 when E_Incomplete_Type =>
4302 if Ada_Version >= Ada_2005 then
4303 Set_Ekind (Id, E_Incomplete_Subtype);
4305 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4306 -- of an incomplete type visible through a limited
4309 if From_With_Type (T)
4310 and then Present (Non_Limited_View (T))
4312 Set_From_With_Type (Id);
4313 Set_Non_Limited_View (Id, Non_Limited_View (T));
4315 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4316 -- to the private dependents of the original incomplete
4317 -- type for future transformation.
4320 Append_Elmt (Id, Private_Dependents (T));
4323 -- If the subtype name denotes an incomplete type an error
4324 -- was already reported by Process_Subtype.
4327 Set_Etype (Id, Any_Type);
4331 raise Program_Error;
4335 if Etype (Id) = Any_Type then
4339 -- Some common processing on all types
4341 Set_Size_Info (Id, T);
4342 Set_First_Rep_Item (Id, First_Rep_Item (T));
4346 Set_Is_Immediately_Visible (Id, True);
4347 Set_Depends_On_Private (Id, Has_Private_Component (T));
4348 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4350 if Is_Interface (T) then
4351 Set_Is_Interface (Id);
4354 if Present (Generic_Parent_Type (N))
4357 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4359 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4360 /= N_Formal_Private_Type_Definition)
4362 if Is_Tagged_Type (Id) then
4364 -- If this is a generic actual subtype for a synchronized type,
4365 -- the primitive operations are those of the corresponding record
4366 -- for which there is a separate subtype declaration.
4368 if Is_Concurrent_Type (Id) then
4370 elsif Is_Class_Wide_Type (Id) then
4371 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4373 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4376 elsif Scope (Etype (Id)) /= Standard_Standard then
4377 Derive_Subprograms (Generic_Parent_Type (N), Id);
4381 if Is_Private_Type (T)
4382 and then Present (Full_View (T))
4384 Conditional_Delay (Id, Full_View (T));
4386 -- The subtypes of components or subcomponents of protected types
4387 -- do not need freeze nodes, which would otherwise appear in the
4388 -- wrong scope (before the freeze node for the protected type). The
4389 -- proper subtypes are those of the subcomponents of the corresponding
4392 elsif Ekind (Scope (Id)) /= E_Protected_Type
4393 and then Present (Scope (Scope (Id))) -- error defense!
4394 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4396 Conditional_Delay (Id, T);
4399 -- Check that Constraint_Error is raised for a scalar subtype indication
4400 -- when the lower or upper bound of a non-null range lies outside the
4401 -- range of the type mark.
4403 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4404 if Is_Scalar_Type (Etype (Id))
4405 and then Scalar_Range (Id) /=
4406 Scalar_Range (Etype (Subtype_Mark
4407 (Subtype_Indication (N))))
4411 Etype (Subtype_Mark (Subtype_Indication (N))));
4413 -- In the array case, check compatibility for each index
4415 elsif Is_Array_Type (Etype (Id))
4416 and then Present (First_Index (Id))
4418 -- This really should be a subprogram that finds the indications
4422 Subt_Index : Node_Id := First_Index (Id);
4423 Target_Index : Node_Id :=
4425 (Subtype_Mark (Subtype_Indication (N))));
4426 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4429 while Present (Subt_Index) loop
4430 if ((Nkind (Subt_Index) = N_Identifier
4431 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4432 or else Nkind (Subt_Index) = N_Subtype_Indication)
4434 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4437 Target_Typ : constant Entity_Id :=
4438 Etype (Target_Index);
4442 (Scalar_Range (Etype (Subt_Index)),
4445 Defining_Identifier (N));
4447 -- Reset Has_Dynamic_Range_Check on the subtype to
4448 -- prevent elision of the index check due to a dynamic
4449 -- check generated for a preceding index (needed since
4450 -- Insert_Range_Checks tries to avoid generating
4451 -- redundant checks on a given declaration).
4453 Set_Has_Dynamic_Range_Check (N, False);
4459 Sloc (Defining_Identifier (N)));
4461 -- Record whether this index involved a dynamic check
4464 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4468 Next_Index (Subt_Index);
4469 Next_Index (Target_Index);
4472 -- Finally, mark whether the subtype involves dynamic checks
4474 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4479 -- Make sure that generic actual types are properly frozen. The subtype
4480 -- is marked as a generic actual type when the enclosing instance is
4481 -- analyzed, so here we identify the subtype from the tree structure.
4484 and then Is_Generic_Actual_Type (Id)
4485 and then In_Instance
4486 and then not Comes_From_Source (N)
4487 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4488 and then Is_Frozen (T)
4490 Freeze_Before (N, Id);
4493 Set_Optimize_Alignment_Flags (Id);
4494 Check_Eliminated (Id);
4497 if Has_Aspects (N) then
4498 Analyze_Aspect_Specifications (N, Id);
4500 end Analyze_Subtype_Declaration;
4502 --------------------------------
4503 -- Analyze_Subtype_Indication --
4504 --------------------------------
4506 procedure Analyze_Subtype_Indication (N : Node_Id) is
4507 T : constant Entity_Id := Subtype_Mark (N);
4508 R : constant Node_Id := Range_Expression (Constraint (N));
4515 Set_Etype (N, Etype (R));
4516 Resolve (R, Entity (T));
4518 Set_Error_Posted (R);
4519 Set_Error_Posted (T);
4521 end Analyze_Subtype_Indication;
4523 --------------------------
4524 -- Analyze_Variant_Part --
4525 --------------------------
4527 procedure Analyze_Variant_Part (N : Node_Id) is
4529 procedure Non_Static_Choice_Error (Choice : Node_Id);
4530 -- Error routine invoked by the generic instantiation below when the
4531 -- variant part has a non static choice.
4533 procedure Process_Declarations (Variant : Node_Id);
4534 -- Analyzes all the declarations associated with a Variant. Needed by
4535 -- the generic instantiation below.
4537 package Variant_Choices_Processing is new
4538 Generic_Choices_Processing
4539 (Get_Alternatives => Variants,
4540 Get_Choices => Discrete_Choices,
4541 Process_Empty_Choice => No_OP,
4542 Process_Non_Static_Choice => Non_Static_Choice_Error,
4543 Process_Associated_Node => Process_Declarations);
4544 use Variant_Choices_Processing;
4545 -- Instantiation of the generic choice processing package
4547 -----------------------------
4548 -- Non_Static_Choice_Error --
4549 -----------------------------
4551 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4553 Flag_Non_Static_Expr
4554 ("choice given in variant part is not static!", Choice);
4555 end Non_Static_Choice_Error;
4557 --------------------------
4558 -- Process_Declarations --
4559 --------------------------
4561 procedure Process_Declarations (Variant : Node_Id) is
4563 if not Null_Present (Component_List (Variant)) then
4564 Analyze_Declarations (Component_Items (Component_List (Variant)));
4566 if Present (Variant_Part (Component_List (Variant))) then
4567 Analyze (Variant_Part (Component_List (Variant)));
4570 end Process_Declarations;
4574 Discr_Name : Node_Id;
4575 Discr_Type : Entity_Id;
4577 Dont_Care : Boolean;
4578 Others_Present : Boolean := False;
4580 pragma Warnings (Off, Dont_Care);
4581 pragma Warnings (Off, Others_Present);
4582 -- We don't care about the assigned values of any of these
4584 -- Start of processing for Analyze_Variant_Part
4587 Discr_Name := Name (N);
4588 Analyze (Discr_Name);
4590 -- If Discr_Name bad, get out (prevent cascaded errors)
4592 if Etype (Discr_Name) = Any_Type then
4596 -- Check invalid discriminant in variant part
4598 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4599 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4602 Discr_Type := Etype (Entity (Discr_Name));
4604 if not Is_Discrete_Type (Discr_Type) then
4606 ("discriminant in a variant part must be of a discrete type",
4611 -- Call the instantiated Analyze_Choices which does the rest of the work
4613 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4614 end Analyze_Variant_Part;
4616 ----------------------------
4617 -- Array_Type_Declaration --
4618 ----------------------------
4620 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4621 Component_Def : constant Node_Id := Component_Definition (Def);
4622 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4623 Element_Type : Entity_Id;
4624 Implicit_Base : Entity_Id;
4626 Related_Id : Entity_Id := Empty;
4628 P : constant Node_Id := Parent (Def);
4632 if Nkind (Def) = N_Constrained_Array_Definition then
4633 Index := First (Discrete_Subtype_Definitions (Def));
4635 Index := First (Subtype_Marks (Def));
4638 -- Find proper names for the implicit types which may be public. In case
4639 -- of anonymous arrays we use the name of the first object of that type
4643 Related_Id := Defining_Identifier (P);
4649 while Present (Index) loop
4652 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4653 Check_SPARK_Restriction ("subtype mark required", Index);
4656 -- Add a subtype declaration for each index of private array type
4657 -- declaration whose etype is also private. For example:
4660 -- type Index is private;
4662 -- type Table is array (Index) of ...
4665 -- This is currently required by the expander for the internally
4666 -- generated equality subprogram of records with variant parts in
4667 -- which the etype of some component is such private type.
4669 if Ekind (Current_Scope) = E_Package
4670 and then In_Private_Part (Current_Scope)
4671 and then Has_Private_Declaration (Etype (Index))
4674 Loc : constant Source_Ptr := Sloc (Def);
4679 New_E := Make_Temporary (Loc, 'T');
4680 Set_Is_Internal (New_E);
4683 Make_Subtype_Declaration (Loc,
4684 Defining_Identifier => New_E,
4685 Subtype_Indication =>
4686 New_Occurrence_Of (Etype (Index), Loc));
4688 Insert_Before (Parent (Def), Decl);
4690 Set_Etype (Index, New_E);
4692 -- If the index is a range the Entity attribute is not
4693 -- available. Example:
4696 -- type T is private;
4698 -- type T is new Natural;
4699 -- Table : array (T(1) .. T(10)) of Boolean;
4702 if Nkind (Index) /= N_Range then
4703 Set_Entity (Index, New_E);
4708 Make_Index (Index, P, Related_Id, Nb_Index);
4710 -- Check error of subtype with predicate for index type
4712 Bad_Predicated_Subtype_Use
4713 ("subtype& has predicate, not allowed as index subtype",
4714 Index, Etype (Index));
4716 -- Move to next index
4719 Nb_Index := Nb_Index + 1;
4722 -- Process subtype indication if one is present
4724 if Present (Component_Typ) then
4725 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4727 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4728 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4731 -- Ada 2005 (AI-230): Access Definition case
4733 else pragma Assert (Present (Access_Definition (Component_Def)));
4735 -- Indicate that the anonymous access type is created by the
4736 -- array type declaration.
4738 Element_Type := Access_Definition
4740 N => Access_Definition (Component_Def));
4741 Set_Is_Local_Anonymous_Access (Element_Type);
4743 -- Propagate the parent. This field is needed if we have to generate
4744 -- the master_id associated with an anonymous access to task type
4745 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4747 Set_Parent (Element_Type, Parent (T));
4749 -- Ada 2005 (AI-230): In case of components that are anonymous access
4750 -- types the level of accessibility depends on the enclosing type
4753 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4755 -- Ada 2005 (AI-254)
4758 CD : constant Node_Id :=
4759 Access_To_Subprogram_Definition
4760 (Access_Definition (Component_Def));
4762 if Present (CD) and then Protected_Present (CD) then
4764 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4769 -- Constrained array case
4772 T := Create_Itype (E_Void, P, Related_Id, 'T');
4775 if Nkind (Def) = N_Constrained_Array_Definition then
4777 -- Establish Implicit_Base as unconstrained base type
4779 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4781 Set_Etype (Implicit_Base, Implicit_Base);
4782 Set_Scope (Implicit_Base, Current_Scope);
4783 Set_Has_Delayed_Freeze (Implicit_Base);
4785 -- The constrained array type is a subtype of the unconstrained one
4787 Set_Ekind (T, E_Array_Subtype);
4788 Init_Size_Align (T);
4789 Set_Etype (T, Implicit_Base);
4790 Set_Scope (T, Current_Scope);
4791 Set_Is_Constrained (T, True);
4792 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4793 Set_Has_Delayed_Freeze (T);
4795 -- Complete setup of implicit base type
4797 Set_First_Index (Implicit_Base, First_Index (T));
4798 Set_Component_Type (Implicit_Base, Element_Type);
4799 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4800 Set_Component_Size (Implicit_Base, Uint_0);
4801 Set_Packed_Array_Type (Implicit_Base, Empty);
4802 Set_Has_Controlled_Component
4803 (Implicit_Base, Has_Controlled_Component
4805 or else Is_Controlled
4807 Set_Finalize_Storage_Only
4808 (Implicit_Base, Finalize_Storage_Only
4811 -- Unconstrained array case
4814 Set_Ekind (T, E_Array_Type);
4815 Init_Size_Align (T);
4817 Set_Scope (T, Current_Scope);
4818 Set_Component_Size (T, Uint_0);
4819 Set_Is_Constrained (T, False);
4820 Set_First_Index (T, First (Subtype_Marks (Def)));
4821 Set_Has_Delayed_Freeze (T, True);
4822 Set_Has_Task (T, Has_Task (Element_Type));
4823 Set_Has_Controlled_Component (T, Has_Controlled_Component
4826 Is_Controlled (Element_Type));
4827 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4831 -- Common attributes for both cases
4833 Set_Component_Type (Base_Type (T), Element_Type);
4834 Set_Packed_Array_Type (T, Empty);
4836 if Aliased_Present (Component_Definition (Def)) then
4837 Check_SPARK_Restriction
4838 ("aliased is not allowed", Component_Definition (Def));
4839 Set_Has_Aliased_Components (Etype (T));
4842 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4843 -- array type to ensure that objects of this type are initialized.
4845 if Ada_Version >= Ada_2005
4846 and then Can_Never_Be_Null (Element_Type)
4848 Set_Can_Never_Be_Null (T);
4850 if Null_Exclusion_Present (Component_Definition (Def))
4852 -- No need to check itypes because in their case this check was
4853 -- done at their point of creation
4855 and then not Is_Itype (Element_Type)
4858 ("`NOT NULL` not allowed (null already excluded)",
4859 Subtype_Indication (Component_Definition (Def)));
4863 Priv := Private_Component (Element_Type);
4865 if Present (Priv) then
4867 -- Check for circular definitions
4869 if Priv = Any_Type then
4870 Set_Component_Type (Etype (T), Any_Type);
4872 -- There is a gap in the visibility of operations on the composite
4873 -- type only if the component type is defined in a different scope.
4875 elsif Scope (Priv) = Current_Scope then
4878 elsif Is_Limited_Type (Priv) then
4879 Set_Is_Limited_Composite (Etype (T));
4880 Set_Is_Limited_Composite (T);
4882 Set_Is_Private_Composite (Etype (T));
4883 Set_Is_Private_Composite (T);
4887 -- A syntax error in the declaration itself may lead to an empty index
4888 -- list, in which case do a minimal patch.
4890 if No (First_Index (T)) then
4891 Error_Msg_N ("missing index definition in array type declaration", T);
4894 Indexes : constant List_Id :=
4895 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4897 Set_Discrete_Subtype_Definitions (Def, Indexes);
4898 Set_First_Index (T, First (Indexes));
4903 -- Create a concatenation operator for the new type. Internal array
4904 -- types created for packed entities do not need such, they are
4905 -- compatible with the user-defined type.
4907 if Number_Dimensions (T) = 1
4908 and then not Is_Packed_Array_Type (T)
4910 New_Concatenation_Op (T);
4913 -- In the case of an unconstrained array the parser has already verified
4914 -- that all the indexes are unconstrained but we still need to make sure
4915 -- that the element type is constrained.
4917 if Is_Indefinite_Subtype (Element_Type) then
4919 ("unconstrained element type in array declaration",
4920 Subtype_Indication (Component_Def));
4922 elsif Is_Abstract_Type (Element_Type) then
4924 ("the type of a component cannot be abstract",
4925 Subtype_Indication (Component_Def));
4927 end Array_Type_Declaration;
4929 ------------------------------------------------------
4930 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4931 ------------------------------------------------------
4933 function Replace_Anonymous_Access_To_Protected_Subprogram
4934 (N : Node_Id) return Entity_Id
4936 Loc : constant Source_Ptr := Sloc (N);
4938 Curr_Scope : constant Scope_Stack_Entry :=
4939 Scope_Stack.Table (Scope_Stack.Last);
4941 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
4948 Set_Is_Internal (Anon);
4951 when N_Component_Declaration |
4952 N_Unconstrained_Array_Definition |
4953 N_Constrained_Array_Definition =>
4954 Comp := Component_Definition (N);
4955 Acc := Access_Definition (Comp);
4957 when N_Discriminant_Specification =>
4958 Comp := Discriminant_Type (N);
4961 when N_Parameter_Specification =>
4962 Comp := Parameter_Type (N);
4965 when N_Access_Function_Definition =>
4966 Comp := Result_Definition (N);
4969 when N_Object_Declaration =>
4970 Comp := Object_Definition (N);
4973 when N_Function_Specification =>
4974 Comp := Result_Definition (N);
4978 raise Program_Error;
4981 Decl := Make_Full_Type_Declaration (Loc,
4982 Defining_Identifier => Anon,
4984 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
4986 Mark_Rewrite_Insertion (Decl);
4988 -- Insert the new declaration in the nearest enclosing scope. If the
4989 -- node is a body and N is its return type, the declaration belongs in
4990 -- the enclosing scope.
4994 if Nkind (P) = N_Subprogram_Body
4995 and then Nkind (N) = N_Function_Specification
5000 while Present (P) and then not Has_Declarations (P) loop
5004 pragma Assert (Present (P));
5006 if Nkind (P) = N_Package_Specification then
5007 Prepend (Decl, Visible_Declarations (P));
5009 Prepend (Decl, Declarations (P));
5012 -- Replace the anonymous type with an occurrence of the new declaration.
5013 -- In all cases the rewritten node does not have the null-exclusion
5014 -- attribute because (if present) it was already inherited by the
5015 -- anonymous entity (Anon). Thus, in case of components we do not
5016 -- inherit this attribute.
5018 if Nkind (N) = N_Parameter_Specification then
5019 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5020 Set_Etype (Defining_Identifier (N), Anon);
5021 Set_Null_Exclusion_Present (N, False);
5023 elsif Nkind (N) = N_Object_Declaration then
5024 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5025 Set_Etype (Defining_Identifier (N), Anon);
5027 elsif Nkind (N) = N_Access_Function_Definition then
5028 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5030 elsif Nkind (N) = N_Function_Specification then
5031 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5032 Set_Etype (Defining_Unit_Name (N), Anon);
5036 Make_Component_Definition (Loc,
5037 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5040 Mark_Rewrite_Insertion (Comp);
5042 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5046 -- Temporarily remove the current scope (record or subprogram) from
5047 -- the stack to add the new declarations to the enclosing scope.
5049 Scope_Stack.Decrement_Last;
5051 Set_Is_Itype (Anon);
5052 Scope_Stack.Append (Curr_Scope);
5055 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5056 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5058 end Replace_Anonymous_Access_To_Protected_Subprogram;
5060 -------------------------------
5061 -- Build_Derived_Access_Type --
5062 -------------------------------
5064 procedure Build_Derived_Access_Type
5066 Parent_Type : Entity_Id;
5067 Derived_Type : Entity_Id)
5069 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5071 Desig_Type : Entity_Id;
5073 Discr_Con_Elist : Elist_Id;
5074 Discr_Con_El : Elmt_Id;
5078 -- Set the designated type so it is available in case this is an access
5079 -- to a self-referential type, e.g. a standard list type with a next
5080 -- pointer. Will be reset after subtype is built.
5082 Set_Directly_Designated_Type
5083 (Derived_Type, Designated_Type (Parent_Type));
5085 Subt := Process_Subtype (S, N);
5087 if Nkind (S) /= N_Subtype_Indication
5088 and then Subt /= Base_Type (Subt)
5090 Set_Ekind (Derived_Type, E_Access_Subtype);
5093 if Ekind (Derived_Type) = E_Access_Subtype then
5095 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5096 Ibase : constant Entity_Id :=
5097 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5098 Svg_Chars : constant Name_Id := Chars (Ibase);
5099 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5102 Copy_Node (Pbase, Ibase);
5104 Set_Chars (Ibase, Svg_Chars);
5105 Set_Next_Entity (Ibase, Svg_Next_E);
5106 Set_Sloc (Ibase, Sloc (Derived_Type));
5107 Set_Scope (Ibase, Scope (Derived_Type));
5108 Set_Freeze_Node (Ibase, Empty);
5109 Set_Is_Frozen (Ibase, False);
5110 Set_Comes_From_Source (Ibase, False);
5111 Set_Is_First_Subtype (Ibase, False);
5113 Set_Etype (Ibase, Pbase);
5114 Set_Etype (Derived_Type, Ibase);
5118 Set_Directly_Designated_Type
5119 (Derived_Type, Designated_Type (Subt));
5121 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5122 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5123 Set_Size_Info (Derived_Type, Parent_Type);
5124 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5125 Set_Depends_On_Private (Derived_Type,
5126 Has_Private_Component (Derived_Type));
5127 Conditional_Delay (Derived_Type, Subt);
5129 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5130 -- that it is not redundant.
5132 if Null_Exclusion_Present (Type_Definition (N)) then
5133 Set_Can_Never_Be_Null (Derived_Type);
5135 if Can_Never_Be_Null (Parent_Type)
5139 ("`NOT NULL` not allowed (& already excludes null)",
5143 elsif Can_Never_Be_Null (Parent_Type) then
5144 Set_Can_Never_Be_Null (Derived_Type);
5147 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5148 -- the root type for this information.
5150 -- Apply range checks to discriminants for derived record case
5151 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5153 Desig_Type := Designated_Type (Derived_Type);
5154 if Is_Composite_Type (Desig_Type)
5155 and then (not Is_Array_Type (Desig_Type))
5156 and then Has_Discriminants (Desig_Type)
5157 and then Base_Type (Desig_Type) /= Desig_Type
5159 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5160 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5162 Discr := First_Discriminant (Base_Type (Desig_Type));
5163 while Present (Discr_Con_El) loop
5164 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5165 Next_Elmt (Discr_Con_El);
5166 Next_Discriminant (Discr);
5169 end Build_Derived_Access_Type;
5171 ------------------------------
5172 -- Build_Derived_Array_Type --
5173 ------------------------------
5175 procedure Build_Derived_Array_Type
5177 Parent_Type : Entity_Id;
5178 Derived_Type : Entity_Id)
5180 Loc : constant Source_Ptr := Sloc (N);
5181 Tdef : constant Node_Id := Type_Definition (N);
5182 Indic : constant Node_Id := Subtype_Indication (Tdef);
5183 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5184 Implicit_Base : Entity_Id;
5185 New_Indic : Node_Id;
5187 procedure Make_Implicit_Base;
5188 -- If the parent subtype is constrained, the derived type is a subtype
5189 -- of an implicit base type derived from the parent base.
5191 ------------------------
5192 -- Make_Implicit_Base --
5193 ------------------------
5195 procedure Make_Implicit_Base is
5198 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5200 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5201 Set_Etype (Implicit_Base, Parent_Base);
5203 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5204 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5206 Set_Has_Delayed_Freeze (Implicit_Base, True);
5207 end Make_Implicit_Base;
5209 -- Start of processing for Build_Derived_Array_Type
5212 if not Is_Constrained (Parent_Type) then
5213 if Nkind (Indic) /= N_Subtype_Indication then
5214 Set_Ekind (Derived_Type, E_Array_Type);
5216 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5217 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5219 Set_Has_Delayed_Freeze (Derived_Type, True);
5223 Set_Etype (Derived_Type, Implicit_Base);
5226 Make_Subtype_Declaration (Loc,
5227 Defining_Identifier => Derived_Type,
5228 Subtype_Indication =>
5229 Make_Subtype_Indication (Loc,
5230 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5231 Constraint => Constraint (Indic)));
5233 Rewrite (N, New_Indic);
5238 if Nkind (Indic) /= N_Subtype_Indication then
5241 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5242 Set_Etype (Derived_Type, Implicit_Base);
5243 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5246 Error_Msg_N ("illegal constraint on constrained type", Indic);
5250 -- If parent type is not a derived type itself, and is declared in
5251 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5252 -- the new type's concatenation operator since Derive_Subprograms
5253 -- will not inherit the parent's operator. If the parent type is
5254 -- unconstrained, the operator is of the unconstrained base type.
5256 if Number_Dimensions (Parent_Type) = 1
5257 and then not Is_Limited_Type (Parent_Type)
5258 and then not Is_Derived_Type (Parent_Type)
5259 and then not Is_Package_Or_Generic_Package
5260 (Scope (Base_Type (Parent_Type)))
5262 if not Is_Constrained (Parent_Type)
5263 and then Is_Constrained (Derived_Type)
5265 New_Concatenation_Op (Implicit_Base);
5267 New_Concatenation_Op (Derived_Type);
5270 end Build_Derived_Array_Type;
5272 -----------------------------------
5273 -- Build_Derived_Concurrent_Type --
5274 -----------------------------------
5276 procedure Build_Derived_Concurrent_Type
5278 Parent_Type : Entity_Id;
5279 Derived_Type : Entity_Id)
5281 Loc : constant Source_Ptr := Sloc (N);
5283 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5284 Corr_Decl : Node_Id;
5285 Corr_Decl_Needed : Boolean;
5286 -- If the derived type has fewer discriminants than its parent, the
5287 -- corresponding record is also a derived type, in order to account for
5288 -- the bound discriminants. We create a full type declaration for it in
5291 Constraint_Present : constant Boolean :=
5292 Nkind (Subtype_Indication (Type_Definition (N))) =
5293 N_Subtype_Indication;
5295 D_Constraint : Node_Id;
5296 New_Constraint : Elist_Id;
5297 Old_Disc : Entity_Id;
5298 New_Disc : Entity_Id;
5302 Set_Stored_Constraint (Derived_Type, No_Elist);
5303 Corr_Decl_Needed := False;
5306 if Present (Discriminant_Specifications (N))
5307 and then Constraint_Present
5309 Old_Disc := First_Discriminant (Parent_Type);
5310 New_Disc := First (Discriminant_Specifications (N));
5311 while Present (New_Disc) and then Present (Old_Disc) loop
5312 Next_Discriminant (Old_Disc);
5317 if Present (Old_Disc) and then Expander_Active then
5319 -- The new type has fewer discriminants, so we need to create a new
5320 -- corresponding record, which is derived from the corresponding
5321 -- record of the parent, and has a stored constraint that captures
5322 -- the values of the discriminant constraints. The corresponding
5323 -- record is needed only if expander is active and code generation is
5326 -- The type declaration for the derived corresponding record has the
5327 -- same discriminant part and constraints as the current declaration.
5328 -- Copy the unanalyzed tree to build declaration.
5330 Corr_Decl_Needed := True;
5331 New_N := Copy_Separate_Tree (N);
5334 Make_Full_Type_Declaration (Loc,
5335 Defining_Identifier => Corr_Record,
5336 Discriminant_Specifications =>
5337 Discriminant_Specifications (New_N),
5339 Make_Derived_Type_Definition (Loc,
5340 Subtype_Indication =>
5341 Make_Subtype_Indication (Loc,
5344 (Corresponding_Record_Type (Parent_Type), Loc),
5347 (Subtype_Indication (Type_Definition (New_N))))));
5350 -- Copy Storage_Size and Relative_Deadline variables if task case
5352 if Is_Task_Type (Parent_Type) then
5353 Set_Storage_Size_Variable (Derived_Type,
5354 Storage_Size_Variable (Parent_Type));
5355 Set_Relative_Deadline_Variable (Derived_Type,
5356 Relative_Deadline_Variable (Parent_Type));
5359 if Present (Discriminant_Specifications (N)) then
5360 Push_Scope (Derived_Type);
5361 Check_Or_Process_Discriminants (N, Derived_Type);
5363 if Constraint_Present then
5365 Expand_To_Stored_Constraint
5367 Build_Discriminant_Constraints
5369 Subtype_Indication (Type_Definition (N)), True));
5374 elsif Constraint_Present then
5376 -- Build constrained subtype and derive from it
5379 Loc : constant Source_Ptr := Sloc (N);
5380 Anon : constant Entity_Id :=
5381 Make_Defining_Identifier (Loc,
5382 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5387 Make_Subtype_Declaration (Loc,
5388 Defining_Identifier => Anon,
5389 Subtype_Indication =>
5390 Subtype_Indication (Type_Definition (N)));
5391 Insert_Before (N, Decl);
5394 Rewrite (Subtype_Indication (Type_Definition (N)),
5395 New_Occurrence_Of (Anon, Loc));
5396 Set_Analyzed (Derived_Type, False);
5402 -- By default, operations and private data are inherited from parent.
5403 -- However, in the presence of bound discriminants, a new corresponding
5404 -- record will be created, see below.
5406 Set_Has_Discriminants
5407 (Derived_Type, Has_Discriminants (Parent_Type));
5408 Set_Corresponding_Record_Type
5409 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5411 -- Is_Constrained is set according the parent subtype, but is set to
5412 -- False if the derived type is declared with new discriminants.
5416 (Is_Constrained (Parent_Type) or else Constraint_Present)
5417 and then not Present (Discriminant_Specifications (N)));
5419 if Constraint_Present then
5420 if not Has_Discriminants (Parent_Type) then
5421 Error_Msg_N ("untagged parent must have discriminants", N);
5423 elsif Present (Discriminant_Specifications (N)) then
5425 -- Verify that new discriminants are used to constrain old ones
5430 (Constraint (Subtype_Indication (Type_Definition (N)))));
5432 Old_Disc := First_Discriminant (Parent_Type);
5434 while Present (D_Constraint) loop
5435 if Nkind (D_Constraint) /= N_Discriminant_Association then
5437 -- Positional constraint. If it is a reference to a new
5438 -- discriminant, it constrains the corresponding old one.
5440 if Nkind (D_Constraint) = N_Identifier then
5441 New_Disc := First_Discriminant (Derived_Type);
5442 while Present (New_Disc) loop
5443 exit when Chars (New_Disc) = Chars (D_Constraint);
5444 Next_Discriminant (New_Disc);
5447 if Present (New_Disc) then
5448 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5452 Next_Discriminant (Old_Disc);
5454 -- if this is a named constraint, search by name for the old
5455 -- discriminants constrained by the new one.
5457 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5459 -- Find new discriminant with that name
5461 New_Disc := First_Discriminant (Derived_Type);
5462 while Present (New_Disc) loop
5464 Chars (New_Disc) = Chars (Expression (D_Constraint));
5465 Next_Discriminant (New_Disc);
5468 if Present (New_Disc) then
5470 -- Verify that new discriminant renames some discriminant
5471 -- of the parent type, and associate the new discriminant
5472 -- with one or more old ones that it renames.
5478 Selector := First (Selector_Names (D_Constraint));
5479 while Present (Selector) loop
5480 Old_Disc := First_Discriminant (Parent_Type);
5481 while Present (Old_Disc) loop
5482 exit when Chars (Old_Disc) = Chars (Selector);
5483 Next_Discriminant (Old_Disc);
5486 if Present (Old_Disc) then
5487 Set_Corresponding_Discriminant
5488 (New_Disc, Old_Disc);
5497 Next (D_Constraint);
5500 New_Disc := First_Discriminant (Derived_Type);
5501 while Present (New_Disc) loop
5502 if No (Corresponding_Discriminant (New_Disc)) then
5504 ("new discriminant& must constrain old one", N, New_Disc);
5507 Subtypes_Statically_Compatible
5509 Etype (Corresponding_Discriminant (New_Disc)))
5512 ("& not statically compatible with parent discriminant",
5516 Next_Discriminant (New_Disc);
5520 elsif Present (Discriminant_Specifications (N)) then
5522 ("missing discriminant constraint in untagged derivation", N);
5525 -- The entity chain of the derived type includes the new discriminants
5526 -- but shares operations with the parent.
5528 if Present (Discriminant_Specifications (N)) then
5529 Old_Disc := First_Discriminant (Parent_Type);
5530 while Present (Old_Disc) loop
5531 if No (Next_Entity (Old_Disc))
5532 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5535 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5539 Next_Discriminant (Old_Disc);
5543 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5544 if Has_Discriminants (Parent_Type) then
5545 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5546 Set_Discriminant_Constraint (
5547 Derived_Type, Discriminant_Constraint (Parent_Type));
5551 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5553 Set_Has_Completion (Derived_Type);
5555 if Corr_Decl_Needed then
5556 Set_Stored_Constraint (Derived_Type, New_Constraint);
5557 Insert_After (N, Corr_Decl);
5558 Analyze (Corr_Decl);
5559 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5561 end Build_Derived_Concurrent_Type;
5563 ------------------------------------
5564 -- Build_Derived_Enumeration_Type --
5565 ------------------------------------
5567 procedure Build_Derived_Enumeration_Type
5569 Parent_Type : Entity_Id;
5570 Derived_Type : Entity_Id)
5572 Loc : constant Source_Ptr := Sloc (N);
5573 Def : constant Node_Id := Type_Definition (N);
5574 Indic : constant Node_Id := Subtype_Indication (Def);
5575 Implicit_Base : Entity_Id;
5576 Literal : Entity_Id;
5577 New_Lit : Entity_Id;
5578 Literals_List : List_Id;
5579 Type_Decl : Node_Id;
5581 Rang_Expr : Node_Id;
5584 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5585 -- not have explicit literals lists we need to process types derived
5586 -- from them specially. This is handled by Derived_Standard_Character.
5587 -- If the parent type is a generic type, there are no literals either,
5588 -- and we construct the same skeletal representation as for the generic
5591 if Is_Standard_Character_Type (Parent_Type) then
5592 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5594 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5600 if Nkind (Indic) /= N_Subtype_Indication then
5602 Make_Attribute_Reference (Loc,
5603 Attribute_Name => Name_First,
5604 Prefix => New_Reference_To (Derived_Type, Loc));
5605 Set_Etype (Lo, Derived_Type);
5608 Make_Attribute_Reference (Loc,
5609 Attribute_Name => Name_Last,
5610 Prefix => New_Reference_To (Derived_Type, Loc));
5611 Set_Etype (Hi, Derived_Type);
5613 Set_Scalar_Range (Derived_Type,
5619 -- Analyze subtype indication and verify compatibility
5620 -- with parent type.
5622 if Base_Type (Process_Subtype (Indic, N)) /=
5623 Base_Type (Parent_Type)
5626 ("illegal constraint for formal discrete type", N);
5632 -- If a constraint is present, analyze the bounds to catch
5633 -- premature usage of the derived literals.
5635 if Nkind (Indic) = N_Subtype_Indication
5636 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5638 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5639 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5642 -- Introduce an implicit base type for the derived type even if there
5643 -- is no constraint attached to it, since this seems closer to the
5644 -- Ada semantics. Build a full type declaration tree for the derived
5645 -- type using the implicit base type as the defining identifier. The
5646 -- build a subtype declaration tree which applies the constraint (if
5647 -- any) have it replace the derived type declaration.
5649 Literal := First_Literal (Parent_Type);
5650 Literals_List := New_List;
5651 while Present (Literal)
5652 and then Ekind (Literal) = E_Enumeration_Literal
5654 -- Literals of the derived type have the same representation as
5655 -- those of the parent type, but this representation can be
5656 -- overridden by an explicit representation clause. Indicate
5657 -- that there is no explicit representation given yet. These
5658 -- derived literals are implicit operations of the new type,
5659 -- and can be overridden by explicit ones.
5661 if Nkind (Literal) = N_Defining_Character_Literal then
5663 Make_Defining_Character_Literal (Loc, Chars (Literal));
5665 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5668 Set_Ekind (New_Lit, E_Enumeration_Literal);
5669 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5670 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5671 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5672 Set_Alias (New_Lit, Literal);
5673 Set_Is_Known_Valid (New_Lit, True);
5675 Append (New_Lit, Literals_List);
5676 Next_Literal (Literal);
5680 Make_Defining_Identifier (Sloc (Derived_Type),
5681 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5683 -- Indicate the proper nature of the derived type. This must be done
5684 -- before analysis of the literals, to recognize cases when a literal
5685 -- may be hidden by a previous explicit function definition (cf.
5688 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5689 Set_Etype (Derived_Type, Implicit_Base);
5692 Make_Full_Type_Declaration (Loc,
5693 Defining_Identifier => Implicit_Base,
5694 Discriminant_Specifications => No_List,
5696 Make_Enumeration_Type_Definition (Loc, Literals_List));
5698 Mark_Rewrite_Insertion (Type_Decl);
5699 Insert_Before (N, Type_Decl);
5700 Analyze (Type_Decl);
5702 -- After the implicit base is analyzed its Etype needs to be changed
5703 -- to reflect the fact that it is derived from the parent type which
5704 -- was ignored during analysis. We also set the size at this point.
5706 Set_Etype (Implicit_Base, Parent_Type);
5708 Set_Size_Info (Implicit_Base, Parent_Type);
5709 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5710 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5712 -- Copy other flags from parent type
5714 Set_Has_Non_Standard_Rep
5715 (Implicit_Base, Has_Non_Standard_Rep
5717 Set_Has_Pragma_Ordered
5718 (Implicit_Base, Has_Pragma_Ordered
5720 Set_Has_Delayed_Freeze (Implicit_Base);
5722 -- Process the subtype indication including a validation check on the
5723 -- constraint, if any. If a constraint is given, its bounds must be
5724 -- implicitly converted to the new type.
5726 if Nkind (Indic) = N_Subtype_Indication then
5728 R : constant Node_Id :=
5729 Range_Expression (Constraint (Indic));
5732 if Nkind (R) = N_Range then
5733 Hi := Build_Scalar_Bound
5734 (High_Bound (R), Parent_Type, Implicit_Base);
5735 Lo := Build_Scalar_Bound
5736 (Low_Bound (R), Parent_Type, Implicit_Base);
5739 -- Constraint is a Range attribute. Replace with explicit
5740 -- mention of the bounds of the prefix, which must be a
5743 Analyze (Prefix (R));
5745 Convert_To (Implicit_Base,
5746 Make_Attribute_Reference (Loc,
5747 Attribute_Name => Name_Last,
5749 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5752 Convert_To (Implicit_Base,
5753 Make_Attribute_Reference (Loc,
5754 Attribute_Name => Name_First,
5756 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5763 (Type_High_Bound (Parent_Type),
5764 Parent_Type, Implicit_Base);
5767 (Type_Low_Bound (Parent_Type),
5768 Parent_Type, Implicit_Base);
5776 -- If we constructed a default range for the case where no range
5777 -- was given, then the expressions in the range must not freeze
5778 -- since they do not correspond to expressions in the source.
5780 if Nkind (Indic) /= N_Subtype_Indication then
5781 Set_Must_Not_Freeze (Lo);
5782 Set_Must_Not_Freeze (Hi);
5783 Set_Must_Not_Freeze (Rang_Expr);
5787 Make_Subtype_Declaration (Loc,
5788 Defining_Identifier => Derived_Type,
5789 Subtype_Indication =>
5790 Make_Subtype_Indication (Loc,
5791 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5793 Make_Range_Constraint (Loc,
5794 Range_Expression => Rang_Expr))));
5798 -- If pragma Discard_Names applies on the first subtype of the parent
5799 -- type, then it must be applied on this subtype as well.
5801 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5802 Set_Discard_Names (Derived_Type);
5805 -- Apply a range check. Since this range expression doesn't have an
5806 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5809 if Nkind (Indic) = N_Subtype_Indication then
5810 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5812 Source_Typ => Entity (Subtype_Mark (Indic)));
5815 end Build_Derived_Enumeration_Type;
5817 --------------------------------
5818 -- Build_Derived_Numeric_Type --
5819 --------------------------------
5821 procedure Build_Derived_Numeric_Type
5823 Parent_Type : Entity_Id;
5824 Derived_Type : Entity_Id)
5826 Loc : constant Source_Ptr := Sloc (N);
5827 Tdef : constant Node_Id := Type_Definition (N);
5828 Indic : constant Node_Id := Subtype_Indication (Tdef);
5829 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5830 No_Constraint : constant Boolean := Nkind (Indic) /=
5831 N_Subtype_Indication;
5832 Implicit_Base : Entity_Id;
5838 -- Process the subtype indication including a validation check on
5839 -- the constraint if any.
5841 Discard_Node (Process_Subtype (Indic, N));
5843 -- Introduce an implicit base type for the derived type even if there
5844 -- is no constraint attached to it, since this seems closer to the Ada
5848 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5850 Set_Etype (Implicit_Base, Parent_Base);
5851 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5852 Set_Size_Info (Implicit_Base, Parent_Base);
5853 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5854 Set_Parent (Implicit_Base, Parent (Derived_Type));
5855 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5857 -- Set RM Size for discrete type or decimal fixed-point type
5858 -- Ordinary fixed-point is excluded, why???
5860 if Is_Discrete_Type (Parent_Base)
5861 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5863 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5866 Set_Has_Delayed_Freeze (Implicit_Base);
5868 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5869 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5871 Set_Scalar_Range (Implicit_Base,
5876 if Has_Infinities (Parent_Base) then
5877 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5880 -- The Derived_Type, which is the entity of the declaration, is a
5881 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5882 -- absence of an explicit constraint.
5884 Set_Etype (Derived_Type, Implicit_Base);
5886 -- If we did not have a constraint, then the Ekind is set from the
5887 -- parent type (otherwise Process_Subtype has set the bounds)
5889 if No_Constraint then
5890 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5893 -- If we did not have a range constraint, then set the range from the
5894 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5897 or else not Has_Range_Constraint (Indic)
5899 Set_Scalar_Range (Derived_Type,
5901 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5902 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5903 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5905 if Has_Infinities (Parent_Type) then
5906 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5909 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5912 Set_Is_Descendent_Of_Address (Derived_Type,
5913 Is_Descendent_Of_Address (Parent_Type));
5914 Set_Is_Descendent_Of_Address (Implicit_Base,
5915 Is_Descendent_Of_Address (Parent_Type));
5917 -- Set remaining type-specific fields, depending on numeric type
5919 if Is_Modular_Integer_Type (Parent_Type) then
5920 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5922 Set_Non_Binary_Modulus
5923 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5926 (Implicit_Base, Is_Known_Valid (Parent_Base));
5928 elsif Is_Floating_Point_Type (Parent_Type) then
5930 -- Digits of base type is always copied from the digits value of
5931 -- the parent base type, but the digits of the derived type will
5932 -- already have been set if there was a constraint present.
5934 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5935 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
5937 if No_Constraint then
5938 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5941 elsif Is_Fixed_Point_Type (Parent_Type) then
5943 -- Small of base type and derived type are always copied from the
5944 -- parent base type, since smalls never change. The delta of the
5945 -- base type is also copied from the parent base type. However the
5946 -- delta of the derived type will have been set already if a
5947 -- constraint was present.
5949 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5950 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5951 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5953 if No_Constraint then
5954 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
5957 -- The scale and machine radix in the decimal case are always
5958 -- copied from the parent base type.
5960 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
5961 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
5962 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
5964 Set_Machine_Radix_10
5965 (Derived_Type, Machine_Radix_10 (Parent_Base));
5966 Set_Machine_Radix_10
5967 (Implicit_Base, Machine_Radix_10 (Parent_Base));
5969 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5971 if No_Constraint then
5972 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
5975 -- the analysis of the subtype_indication sets the
5976 -- digits value of the derived type.
5983 -- The type of the bounds is that of the parent type, and they
5984 -- must be converted to the derived type.
5986 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
5988 -- The implicit_base should be frozen when the derived type is frozen,
5989 -- but note that it is used in the conversions of the bounds. For fixed
5990 -- types we delay the determination of the bounds until the proper
5991 -- freezing point. For other numeric types this is rejected by GCC, for
5992 -- reasons that are currently unclear (???), so we choose to freeze the
5993 -- implicit base now. In the case of integers and floating point types
5994 -- this is harmless because subsequent representation clauses cannot
5995 -- affect anything, but it is still baffling that we cannot use the
5996 -- same mechanism for all derived numeric types.
5998 -- There is a further complication: actually *some* representation
5999 -- clauses can affect the implicit base type. Namely, attribute
6000 -- definition clauses for stream-oriented attributes need to set the
6001 -- corresponding TSS entries on the base type, and this normally cannot
6002 -- be done after the base type is frozen, so the circuitry in
6003 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6004 -- not use Set_TSS in this case.
6006 if Is_Fixed_Point_Type (Parent_Type) then
6007 Conditional_Delay (Implicit_Base, Parent_Type);
6009 Freeze_Before (N, Implicit_Base);
6011 end Build_Derived_Numeric_Type;
6013 --------------------------------
6014 -- Build_Derived_Private_Type --
6015 --------------------------------
6017 procedure Build_Derived_Private_Type
6019 Parent_Type : Entity_Id;
6020 Derived_Type : Entity_Id;
6021 Is_Completion : Boolean;
6022 Derive_Subps : Boolean := True)
6024 Loc : constant Source_Ptr := Sloc (N);
6025 Der_Base : Entity_Id;
6027 Full_Decl : Node_Id := Empty;
6028 Full_Der : Entity_Id;
6030 Last_Discr : Entity_Id;
6031 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6032 Swapped : Boolean := False;
6034 procedure Copy_And_Build;
6035 -- Copy derived type declaration, replace parent with its full view,
6036 -- and analyze new declaration.
6038 --------------------
6039 -- Copy_And_Build --
6040 --------------------
6042 procedure Copy_And_Build is
6046 if Ekind (Parent_Type) in Record_Kind
6048 (Ekind (Parent_Type) in Enumeration_Kind
6049 and then not Is_Standard_Character_Type (Parent_Type)
6050 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6052 Full_N := New_Copy_Tree (N);
6053 Insert_After (N, Full_N);
6054 Build_Derived_Type (
6055 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6058 Build_Derived_Type (
6059 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6063 -- Start of processing for Build_Derived_Private_Type
6066 if Is_Tagged_Type (Parent_Type) then
6067 Full_P := Full_View (Parent_Type);
6069 -- A type extension of a type with unknown discriminants is an
6070 -- indefinite type that the back-end cannot handle directly.
6071 -- We treat it as a private type, and build a completion that is
6072 -- derived from the full view of the parent, and hopefully has
6073 -- known discriminants.
6075 -- If the full view of the parent type has an underlying record view,
6076 -- use it to generate the underlying record view of this derived type
6077 -- (required for chains of derivations with unknown discriminants).
6079 -- Minor optimization: we avoid the generation of useless underlying
6080 -- record view entities if the private type declaration has unknown
6081 -- discriminants but its corresponding full view has no
6084 if Has_Unknown_Discriminants (Parent_Type)
6085 and then Present (Full_P)
6086 and then (Has_Discriminants (Full_P)
6087 or else Present (Underlying_Record_View (Full_P)))
6088 and then not In_Open_Scopes (Par_Scope)
6089 and then Expander_Active
6092 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6093 New_Ext : constant Node_Id :=
6095 (Record_Extension_Part (Type_Definition (N)));
6099 Build_Derived_Record_Type
6100 (N, Parent_Type, Derived_Type, Derive_Subps);
6102 -- Build anonymous completion, as a derivation from the full
6103 -- view of the parent. This is not a completion in the usual
6104 -- sense, because the current type is not private.
6107 Make_Full_Type_Declaration (Loc,
6108 Defining_Identifier => Full_Der,
6110 Make_Derived_Type_Definition (Loc,
6111 Subtype_Indication =>
6113 (Subtype_Indication (Type_Definition (N))),
6114 Record_Extension_Part => New_Ext));
6116 -- If the parent type has an underlying record view, use it
6117 -- here to build the new underlying record view.
6119 if Present (Underlying_Record_View (Full_P)) then
6121 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6123 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6124 Underlying_Record_View (Full_P));
6127 Install_Private_Declarations (Par_Scope);
6128 Install_Visible_Declarations (Par_Scope);
6129 Insert_Before (N, Decl);
6131 -- Mark entity as an underlying record view before analysis,
6132 -- to avoid generating the list of its primitive operations
6133 -- (which is not really required for this entity) and thus
6134 -- prevent spurious errors associated with missing overriding
6135 -- of abstract primitives (overridden only for Derived_Type).
6137 Set_Ekind (Full_Der, E_Record_Type);
6138 Set_Is_Underlying_Record_View (Full_Der);
6142 pragma Assert (Has_Discriminants (Full_Der)
6143 and then not Has_Unknown_Discriminants (Full_Der));
6145 Uninstall_Declarations (Par_Scope);
6147 -- Freeze the underlying record view, to prevent generation of
6148 -- useless dispatching information, which is simply shared with
6149 -- the real derived type.
6151 Set_Is_Frozen (Full_Der);
6153 -- Set up links between real entity and underlying record view
6155 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6156 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6159 -- If discriminants are known, build derived record
6162 Build_Derived_Record_Type
6163 (N, Parent_Type, Derived_Type, Derive_Subps);
6168 elsif Has_Discriminants (Parent_Type) then
6169 if Present (Full_View (Parent_Type)) then
6170 if not Is_Completion then
6172 -- Copy declaration for subsequent analysis, to provide a
6173 -- completion for what is a private declaration. Indicate that
6174 -- the full type is internally generated.
6176 Full_Decl := New_Copy_Tree (N);
6177 Full_Der := New_Copy (Derived_Type);
6178 Set_Comes_From_Source (Full_Decl, False);
6179 Set_Comes_From_Source (Full_Der, False);
6180 Set_Parent (Full_Der, Full_Decl);
6182 Insert_After (N, Full_Decl);
6185 -- If this is a completion, the full view being built is itself
6186 -- private. We build a subtype of the parent with the same
6187 -- constraints as this full view, to convey to the back end the
6188 -- constrained components and the size of this subtype. If the
6189 -- parent is constrained, its full view can serve as the
6190 -- underlying full view of the derived type.
6192 if No (Discriminant_Specifications (N)) then
6193 if Nkind (Subtype_Indication (Type_Definition (N))) =
6194 N_Subtype_Indication
6196 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6198 elsif Is_Constrained (Full_View (Parent_Type)) then
6199 Set_Underlying_Full_View
6200 (Derived_Type, Full_View (Parent_Type));
6204 -- If there are new discriminants, the parent subtype is
6205 -- constrained by them, but it is not clear how to build
6206 -- the Underlying_Full_View in this case???
6213 -- Build partial view of derived type from partial view of parent
6215 Build_Derived_Record_Type
6216 (N, Parent_Type, Derived_Type, Derive_Subps);
6218 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6219 if not In_Open_Scopes (Par_Scope)
6220 or else not In_Same_Source_Unit (N, Parent_Type)
6222 -- Swap partial and full views temporarily
6224 Install_Private_Declarations (Par_Scope);
6225 Install_Visible_Declarations (Par_Scope);
6229 -- Build full view of derived type from full view of parent which
6230 -- is now installed. Subprograms have been derived on the partial
6231 -- view, the completion does not derive them anew.
6233 if not Is_Tagged_Type (Parent_Type) then
6235 -- If the parent is itself derived from another private type,
6236 -- installing the private declarations has not affected its
6237 -- privacy status, so use its own full view explicitly.
6239 if Is_Private_Type (Parent_Type) then
6240 Build_Derived_Record_Type
6241 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6243 Build_Derived_Record_Type
6244 (Full_Decl, Parent_Type, Full_Der, False);
6248 -- If full view of parent is tagged, the completion inherits
6249 -- the proper primitive operations.
6251 Set_Defining_Identifier (Full_Decl, Full_Der);
6252 Build_Derived_Record_Type
6253 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6256 -- The full declaration has been introduced into the tree and
6257 -- processed in the step above. It should not be analyzed again
6258 -- (when encountered later in the current list of declarations)
6259 -- to prevent spurious name conflicts. The full entity remains
6262 Set_Analyzed (Full_Decl);
6265 Uninstall_Declarations (Par_Scope);
6267 if In_Open_Scopes (Par_Scope) then
6268 Install_Visible_Declarations (Par_Scope);
6272 Der_Base := Base_Type (Derived_Type);
6273 Set_Full_View (Derived_Type, Full_Der);
6274 Set_Full_View (Der_Base, Base_Type (Full_Der));
6276 -- Copy the discriminant list from full view to the partial views
6277 -- (base type and its subtype). Gigi requires that the partial and
6278 -- full views have the same discriminants.
6280 -- Note that since the partial view is pointing to discriminants
6281 -- in the full view, their scope will be that of the full view.
6282 -- This might cause some front end problems and need adjustment???
6284 Discr := First_Discriminant (Base_Type (Full_Der));
6285 Set_First_Entity (Der_Base, Discr);
6288 Last_Discr := Discr;
6289 Next_Discriminant (Discr);
6290 exit when No (Discr);
6293 Set_Last_Entity (Der_Base, Last_Discr);
6295 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6296 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6297 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6300 -- If this is a completion, the derived type stays private and
6301 -- there is no need to create a further full view, except in the
6302 -- unusual case when the derivation is nested within a child unit,
6308 elsif Present (Full_View (Parent_Type))
6309 and then Has_Discriminants (Full_View (Parent_Type))
6311 if Has_Unknown_Discriminants (Parent_Type)
6312 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6313 N_Subtype_Indication
6316 ("cannot constrain type with unknown discriminants",
6317 Subtype_Indication (Type_Definition (N)));
6321 -- If full view of parent is a record type, build full view as a
6322 -- derivation from the parent's full view. Partial view remains
6323 -- private. For code generation and linking, the full view must have
6324 -- the same public status as the partial one. This full view is only
6325 -- needed if the parent type is in an enclosing scope, so that the
6326 -- full view may actually become visible, e.g. in a child unit. This
6327 -- is both more efficient, and avoids order of freezing problems with
6328 -- the added entities.
6330 if not Is_Private_Type (Full_View (Parent_Type))
6331 and then (In_Open_Scopes (Scope (Parent_Type)))
6334 Make_Defining_Identifier
6335 (Sloc (Derived_Type), Chars (Derived_Type));
6336 Set_Is_Itype (Full_Der);
6337 Set_Has_Private_Declaration (Full_Der);
6338 Set_Has_Private_Declaration (Derived_Type);
6339 Set_Associated_Node_For_Itype (Full_Der, N);
6340 Set_Parent (Full_Der, Parent (Derived_Type));
6341 Set_Full_View (Derived_Type, Full_Der);
6342 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6343 Full_P := Full_View (Parent_Type);
6344 Exchange_Declarations (Parent_Type);
6346 Exchange_Declarations (Full_P);
6349 Build_Derived_Record_Type
6350 (N, Full_View (Parent_Type), Derived_Type,
6351 Derive_Subps => False);
6354 -- In any case, the primitive operations are inherited from the
6355 -- parent type, not from the internal full view.
6357 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6359 if Derive_Subps then
6360 Derive_Subprograms (Parent_Type, Derived_Type);
6364 -- Untagged type, No discriminants on either view
6366 if Nkind (Subtype_Indication (Type_Definition (N))) =
6367 N_Subtype_Indication
6370 ("illegal constraint on type without discriminants", N);
6373 if Present (Discriminant_Specifications (N))
6374 and then Present (Full_View (Parent_Type))
6375 and then not Is_Tagged_Type (Full_View (Parent_Type))
6377 Error_Msg_N ("cannot add discriminants to untagged type", N);
6380 Set_Stored_Constraint (Derived_Type, No_Elist);
6381 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6382 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6383 Set_Has_Controlled_Component
6384 (Derived_Type, Has_Controlled_Component
6387 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6389 if not Is_Controlled (Parent_Type) then
6390 Set_Finalize_Storage_Only
6391 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6394 -- Construct the implicit full view by deriving from full view of the
6395 -- parent type. In order to get proper visibility, we install the
6396 -- parent scope and its declarations.
6398 -- ??? If the parent is untagged private and its completion is
6399 -- tagged, this mechanism will not work because we cannot derive from
6400 -- the tagged full view unless we have an extension.
6402 if Present (Full_View (Parent_Type))
6403 and then not Is_Tagged_Type (Full_View (Parent_Type))
6404 and then not Is_Completion
6407 Make_Defining_Identifier
6408 (Sloc (Derived_Type), Chars (Derived_Type));
6409 Set_Is_Itype (Full_Der);
6410 Set_Has_Private_Declaration (Full_Der);
6411 Set_Has_Private_Declaration (Derived_Type);
6412 Set_Associated_Node_For_Itype (Full_Der, N);
6413 Set_Parent (Full_Der, Parent (Derived_Type));
6414 Set_Full_View (Derived_Type, Full_Der);
6416 if not In_Open_Scopes (Par_Scope) then
6417 Install_Private_Declarations (Par_Scope);
6418 Install_Visible_Declarations (Par_Scope);
6420 Uninstall_Declarations (Par_Scope);
6422 -- If parent scope is open and in another unit, and parent has a
6423 -- completion, then the derivation is taking place in the visible
6424 -- part of a child unit. In that case retrieve the full view of
6425 -- the parent momentarily.
6427 elsif not In_Same_Source_Unit (N, Parent_Type) then
6428 Full_P := Full_View (Parent_Type);
6429 Exchange_Declarations (Parent_Type);
6431 Exchange_Declarations (Full_P);
6433 -- Otherwise it is a local derivation
6439 Set_Scope (Full_Der, Current_Scope);
6440 Set_Is_First_Subtype (Full_Der,
6441 Is_First_Subtype (Derived_Type));
6442 Set_Has_Size_Clause (Full_Der, False);
6443 Set_Has_Alignment_Clause (Full_Der, False);
6444 Set_Next_Entity (Full_Der, Empty);
6445 Set_Has_Delayed_Freeze (Full_Der);
6446 Set_Is_Frozen (Full_Der, False);
6447 Set_Freeze_Node (Full_Der, Empty);
6448 Set_Depends_On_Private (Full_Der,
6449 Has_Private_Component (Full_Der));
6450 Set_Public_Status (Full_Der);
6454 Set_Has_Unknown_Discriminants (Derived_Type,
6455 Has_Unknown_Discriminants (Parent_Type));
6457 if Is_Private_Type (Derived_Type) then
6458 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6461 if Is_Private_Type (Parent_Type)
6462 and then Base_Type (Parent_Type) = Parent_Type
6463 and then In_Open_Scopes (Scope (Parent_Type))
6465 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6467 if Is_Child_Unit (Scope (Current_Scope))
6468 and then Is_Completion
6469 and then In_Private_Part (Current_Scope)
6470 and then Scope (Parent_Type) /= Current_Scope
6472 -- This is the unusual case where a type completed by a private
6473 -- derivation occurs within a package nested in a child unit, and
6474 -- the parent is declared in an ancestor. In this case, the full
6475 -- view of the parent type will become visible in the body of
6476 -- the enclosing child, and only then will the current type be
6477 -- possibly non-private. We build a underlying full view that
6478 -- will be installed when the enclosing child body is compiled.
6481 Make_Defining_Identifier
6482 (Sloc (Derived_Type), Chars (Derived_Type));
6483 Set_Is_Itype (Full_Der);
6484 Build_Itype_Reference (Full_Der, N);
6486 -- The full view will be used to swap entities on entry/exit to
6487 -- the body, and must appear in the entity list for the package.
6489 Append_Entity (Full_Der, Scope (Derived_Type));
6490 Set_Has_Private_Declaration (Full_Der);
6491 Set_Has_Private_Declaration (Derived_Type);
6492 Set_Associated_Node_For_Itype (Full_Der, N);
6493 Set_Parent (Full_Der, Parent (Derived_Type));
6494 Full_P := Full_View (Parent_Type);
6495 Exchange_Declarations (Parent_Type);
6497 Exchange_Declarations (Full_P);
6498 Set_Underlying_Full_View (Derived_Type, Full_Der);
6501 end Build_Derived_Private_Type;
6503 -------------------------------
6504 -- Build_Derived_Record_Type --
6505 -------------------------------
6509 -- Ideally we would like to use the same model of type derivation for
6510 -- tagged and untagged record types. Unfortunately this is not quite
6511 -- possible because the semantics of representation clauses is different
6512 -- for tagged and untagged records under inheritance. Consider the
6515 -- type R (...) is [tagged] record ... end record;
6516 -- type T (...) is new R (...) [with ...];
6518 -- The representation clauses for T can specify a completely different
6519 -- record layout from R's. Hence the same component can be placed in two
6520 -- very different positions in objects of type T and R. If R and T are
6521 -- tagged types, representation clauses for T can only specify the layout
6522 -- of non inherited components, thus components that are common in R and T
6523 -- have the same position in objects of type R and T.
6525 -- This has two implications. The first is that the entire tree for R's
6526 -- declaration needs to be copied for T in the untagged case, so that T
6527 -- can be viewed as a record type of its own with its own representation
6528 -- clauses. The second implication is the way we handle discriminants.
6529 -- Specifically, in the untagged case we need a way to communicate to Gigi
6530 -- what are the real discriminants in the record, while for the semantics
6531 -- we need to consider those introduced by the user to rename the
6532 -- discriminants in the parent type. This is handled by introducing the
6533 -- notion of stored discriminants. See below for more.
6535 -- Fortunately the way regular components are inherited can be handled in
6536 -- the same way in tagged and untagged types.
6538 -- To complicate things a bit more the private view of a private extension
6539 -- cannot be handled in the same way as the full view (for one thing the
6540 -- semantic rules are somewhat different). We will explain what differs
6543 -- 2. DISCRIMINANTS UNDER INHERITANCE
6545 -- The semantic rules governing the discriminants of derived types are
6548 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6549 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6551 -- If parent type has discriminants, then the discriminants that are
6552 -- declared in the derived type are [3.4 (11)]:
6554 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6557 -- o Otherwise, each discriminant of the parent type (implicitly declared
6558 -- in the same order with the same specifications). In this case, the
6559 -- discriminants are said to be "inherited", or if unknown in the parent
6560 -- are also unknown in the derived type.
6562 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6564 -- o The parent subtype shall be constrained;
6566 -- o If the parent type is not a tagged type, then each discriminant of
6567 -- the derived type shall be used in the constraint defining a parent
6568 -- subtype. [Implementation note: This ensures that the new discriminant
6569 -- can share storage with an existing discriminant.]
6571 -- For the derived type each discriminant of the parent type is either
6572 -- inherited, constrained to equal some new discriminant of the derived
6573 -- type, or constrained to the value of an expression.
6575 -- When inherited or constrained to equal some new discriminant, the
6576 -- parent discriminant and the discriminant of the derived type are said
6579 -- If a discriminant of the parent type is constrained to a specific value
6580 -- in the derived type definition, then the discriminant is said to be
6581 -- "specified" by that derived type definition.
6583 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6585 -- We have spoken about stored discriminants in point 1 (introduction)
6586 -- above. There are two sort of stored discriminants: implicit and
6587 -- explicit. As long as the derived type inherits the same discriminants as
6588 -- the root record type, stored discriminants are the same as regular
6589 -- discriminants, and are said to be implicit. However, if any discriminant
6590 -- in the root type was renamed in the derived type, then the derived
6591 -- type will contain explicit stored discriminants. Explicit stored
6592 -- discriminants are discriminants in addition to the semantically visible
6593 -- discriminants defined for the derived type. Stored discriminants are
6594 -- used by Gigi to figure out what are the physical discriminants in
6595 -- objects of the derived type (see precise definition in einfo.ads).
6596 -- As an example, consider the following:
6598 -- type R (D1, D2, D3 : Int) is record ... end record;
6599 -- type T1 is new R;
6600 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6601 -- type T3 is new T2;
6602 -- type T4 (Y : Int) is new T3 (Y, 99);
6604 -- The following table summarizes the discriminants and stored
6605 -- discriminants in R and T1 through T4.
6607 -- Type Discrim Stored Discrim Comment
6608 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6609 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6610 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6611 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6612 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6614 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6615 -- find the corresponding discriminant in the parent type, while
6616 -- Original_Record_Component (abbreviated ORC below), the actual physical
6617 -- component that is renamed. Finally the field Is_Completely_Hidden
6618 -- (abbreviated ICH below) is set for all explicit stored discriminants
6619 -- (see einfo.ads for more info). For the above example this gives:
6621 -- Discrim CD ORC ICH
6622 -- ^^^^^^^ ^^ ^^^ ^^^
6623 -- D1 in R empty itself no
6624 -- D2 in R empty itself no
6625 -- D3 in R empty itself no
6627 -- D1 in T1 D1 in R itself no
6628 -- D2 in T1 D2 in R itself no
6629 -- D3 in T1 D3 in R itself no
6631 -- X1 in T2 D3 in T1 D3 in T2 no
6632 -- X2 in T2 D1 in T1 D1 in T2 no
6633 -- D1 in T2 empty itself yes
6634 -- D2 in T2 empty itself yes
6635 -- D3 in T2 empty itself yes
6637 -- X1 in T3 X1 in T2 D3 in T3 no
6638 -- X2 in T3 X2 in T2 D1 in T3 no
6639 -- D1 in T3 empty itself yes
6640 -- D2 in T3 empty itself yes
6641 -- D3 in T3 empty itself yes
6643 -- Y in T4 X1 in T3 D3 in T3 no
6644 -- D1 in T3 empty itself yes
6645 -- D2 in T3 empty itself yes
6646 -- D3 in T3 empty itself yes
6648 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6650 -- Type derivation for tagged types is fairly straightforward. If no
6651 -- discriminants are specified by the derived type, these are inherited
6652 -- from the parent. No explicit stored discriminants are ever necessary.
6653 -- The only manipulation that is done to the tree is that of adding a
6654 -- _parent field with parent type and constrained to the same constraint
6655 -- specified for the parent in the derived type definition. For instance:
6657 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6658 -- type T1 is new R with null record;
6659 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6661 -- are changed into:
6663 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6664 -- _parent : R (D1, D2, D3);
6667 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6668 -- _parent : T1 (X2, 88, X1);
6671 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6672 -- ORC and ICH fields are:
6674 -- Discrim CD ORC ICH
6675 -- ^^^^^^^ ^^ ^^^ ^^^
6676 -- D1 in R empty itself no
6677 -- D2 in R empty itself no
6678 -- D3 in R empty itself no
6680 -- D1 in T1 D1 in R D1 in R no
6681 -- D2 in T1 D2 in R D2 in R no
6682 -- D3 in T1 D3 in R D3 in R no
6684 -- X1 in T2 D3 in T1 D3 in R no
6685 -- X2 in T2 D1 in T1 D1 in R no
6687 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6689 -- Regardless of whether we dealing with a tagged or untagged type
6690 -- we will transform all derived type declarations of the form
6692 -- type T is new R (...) [with ...];
6694 -- subtype S is R (...);
6695 -- type T is new S [with ...];
6697 -- type BT is new R [with ...];
6698 -- subtype T is BT (...);
6700 -- That is, the base derived type is constrained only if it has no
6701 -- discriminants. The reason for doing this is that GNAT's semantic model
6702 -- assumes that a base type with discriminants is unconstrained.
6704 -- Note that, strictly speaking, the above transformation is not always
6705 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6707 -- procedure B34011A is
6708 -- type REC (D : integer := 0) is record
6713 -- type T6 is new Rec;
6714 -- function F return T6;
6719 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6722 -- The definition of Q6.U is illegal. However transforming Q6.U into
6724 -- type BaseU is new T6;
6725 -- subtype U is BaseU (Q6.F.I)
6727 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6728 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6729 -- the transformation described above.
6731 -- There is another instance where the above transformation is incorrect.
6735 -- type Base (D : Integer) is tagged null record;
6736 -- procedure P (X : Base);
6738 -- type Der is new Base (2) with null record;
6739 -- procedure P (X : Der);
6742 -- Then the above transformation turns this into
6744 -- type Der_Base is new Base with null record;
6745 -- -- procedure P (X : Base) is implicitly inherited here
6746 -- -- as procedure P (X : Der_Base).
6748 -- subtype Der is Der_Base (2);
6749 -- procedure P (X : Der);
6750 -- -- The overriding of P (X : Der_Base) is illegal since we
6751 -- -- have a parameter conformance problem.
6753 -- To get around this problem, after having semantically processed Der_Base
6754 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6755 -- Discriminant_Constraint from Der so that when parameter conformance is
6756 -- checked when P is overridden, no semantic errors are flagged.
6758 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6760 -- Regardless of whether we are dealing with a tagged or untagged type
6761 -- we will transform all derived type declarations of the form
6763 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6764 -- type T is new R [with ...];
6766 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6768 -- The reason for such transformation is that it allows us to implement a
6769 -- very clean form of component inheritance as explained below.
6771 -- Note that this transformation is not achieved by direct tree rewriting
6772 -- and manipulation, but rather by redoing the semantic actions that the
6773 -- above transformation will entail. This is done directly in routine
6774 -- Inherit_Components.
6776 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6778 -- In both tagged and untagged derived types, regular non discriminant
6779 -- components are inherited in the derived type from the parent type. In
6780 -- the absence of discriminants component, inheritance is straightforward
6781 -- as components can simply be copied from the parent.
6783 -- If the parent has discriminants, inheriting components constrained with
6784 -- these discriminants requires caution. Consider the following example:
6786 -- type R (D1, D2 : Positive) is [tagged] record
6787 -- S : String (D1 .. D2);
6790 -- type T1 is new R [with null record];
6791 -- type T2 (X : positive) is new R (1, X) [with null record];
6793 -- As explained in 6. above, T1 is rewritten as
6794 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6795 -- which makes the treatment for T1 and T2 identical.
6797 -- What we want when inheriting S, is that references to D1 and D2 in R are
6798 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6799 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6800 -- with either discriminant references in the derived type or expressions.
6801 -- This replacement is achieved as follows: before inheriting R's
6802 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6803 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6804 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6805 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6806 -- by String (1 .. X).
6808 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6810 -- We explain here the rules governing private type extensions relevant to
6811 -- type derivation. These rules are explained on the following example:
6813 -- type D [(...)] is new A [(...)] with private; <-- partial view
6814 -- type D [(...)] is new P [(...)] with null record; <-- full view
6816 -- Type A is called the ancestor subtype of the private extension.
6817 -- Type P is the parent type of the full view of the private extension. It
6818 -- must be A or a type derived from A.
6820 -- The rules concerning the discriminants of private type extensions are
6823 -- o If a private extension inherits known discriminants from the ancestor
6824 -- subtype, then the full view shall also inherit its discriminants from
6825 -- the ancestor subtype and the parent subtype of the full view shall be
6826 -- constrained if and only if the ancestor subtype is constrained.
6828 -- o If a partial view has unknown discriminants, then the full view may
6829 -- define a definite or an indefinite subtype, with or without
6832 -- o If a partial view has neither known nor unknown discriminants, then
6833 -- the full view shall define a definite subtype.
6835 -- o If the ancestor subtype of a private extension has constrained
6836 -- discriminants, then the parent subtype of the full view shall impose a
6837 -- statically matching constraint on those discriminants.
6839 -- This means that only the following forms of private extensions are
6842 -- type D is new A with private; <-- partial view
6843 -- type D is new P with null record; <-- full view
6845 -- If A has no discriminants than P has no discriminants, otherwise P must
6846 -- inherit A's discriminants.
6848 -- type D is new A (...) with private; <-- partial view
6849 -- type D is new P (:::) with null record; <-- full view
6851 -- P must inherit A's discriminants and (...) and (:::) must statically
6854 -- subtype A is R (...);
6855 -- type D is new A with private; <-- partial view
6856 -- type D is new P with null record; <-- full view
6858 -- P must have inherited R's discriminants and must be derived from A or
6859 -- any of its subtypes.
6861 -- type D (..) is new A with private; <-- partial view
6862 -- type D (..) is new P [(:::)] with null record; <-- full view
6864 -- No specific constraints on P's discriminants or constraint (:::).
6865 -- Note that A can be unconstrained, but the parent subtype P must either
6866 -- be constrained or (:::) must be present.
6868 -- type D (..) is new A [(...)] with private; <-- partial view
6869 -- type D (..) is new P [(:::)] with null record; <-- full view
6871 -- P's constraints on A's discriminants must statically match those
6872 -- imposed by (...).
6874 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6876 -- The full view of a private extension is handled exactly as described
6877 -- above. The model chose for the private view of a private extension is
6878 -- the same for what concerns discriminants (i.e. they receive the same
6879 -- treatment as in the tagged case). However, the private view of the
6880 -- private extension always inherits the components of the parent base,
6881 -- without replacing any discriminant reference. Strictly speaking this is
6882 -- incorrect. However, Gigi never uses this view to generate code so this
6883 -- is a purely semantic issue. In theory, a set of transformations similar
6884 -- to those given in 5. and 6. above could be applied to private views of
6885 -- private extensions to have the same model of component inheritance as
6886 -- for non private extensions. However, this is not done because it would
6887 -- further complicate private type processing. Semantically speaking, this
6888 -- leaves us in an uncomfortable situation. As an example consider:
6891 -- type R (D : integer) is tagged record
6892 -- S : String (1 .. D);
6894 -- procedure P (X : R);
6895 -- type T is new R (1) with private;
6897 -- type T is new R (1) with null record;
6900 -- This is transformed into:
6903 -- type R (D : integer) is tagged record
6904 -- S : String (1 .. D);
6906 -- procedure P (X : R);
6907 -- type T is new R (1) with private;
6909 -- type BaseT is new R with null record;
6910 -- subtype T is BaseT (1);
6913 -- (strictly speaking the above is incorrect Ada)
6915 -- From the semantic standpoint the private view of private extension T
6916 -- should be flagged as constrained since one can clearly have
6920 -- in a unit withing Pack. However, when deriving subprograms for the
6921 -- private view of private extension T, T must be seen as unconstrained
6922 -- since T has discriminants (this is a constraint of the current
6923 -- subprogram derivation model). Thus, when processing the private view of
6924 -- a private extension such as T, we first mark T as unconstrained, we
6925 -- process it, we perform program derivation and just before returning from
6926 -- Build_Derived_Record_Type we mark T as constrained.
6928 -- ??? Are there are other uncomfortable cases that we will have to
6931 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6933 -- Types that are derived from a visible record type and have a private
6934 -- extension present other peculiarities. They behave mostly like private
6935 -- types, but if they have primitive operations defined, these will not
6936 -- have the proper signatures for further inheritance, because other
6937 -- primitive operations will use the implicit base that we define for
6938 -- private derivations below. This affect subprogram inheritance (see
6939 -- Derive_Subprograms for details). We also derive the implicit base from
6940 -- the base type of the full view, so that the implicit base is a record
6941 -- type and not another private type, This avoids infinite loops.
6943 procedure Build_Derived_Record_Type
6945 Parent_Type : Entity_Id;
6946 Derived_Type : Entity_Id;
6947 Derive_Subps : Boolean := True)
6949 Loc : constant Source_Ptr := Sloc (N);
6950 Parent_Base : Entity_Id;
6953 Discrim : Entity_Id;
6954 Last_Discrim : Entity_Id;
6957 Discs : Elist_Id := New_Elmt_List;
6958 -- An empty Discs list means that there were no constraints in the
6959 -- subtype indication or that there was an error processing it.
6961 Assoc_List : Elist_Id;
6962 New_Discrs : Elist_Id;
6963 New_Base : Entity_Id;
6965 New_Indic : Node_Id;
6967 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6968 Discriminant_Specs : constant Boolean :=
6969 Present (Discriminant_Specifications (N));
6970 Private_Extension : constant Boolean :=
6971 Nkind (N) = N_Private_Extension_Declaration;
6973 Constraint_Present : Boolean;
6974 Inherit_Discrims : Boolean := False;
6975 Save_Etype : Entity_Id;
6976 Save_Discr_Constr : Elist_Id;
6977 Save_Next_Entity : Entity_Id;
6980 if Ekind (Parent_Type) = E_Record_Type_With_Private
6981 and then Present (Full_View (Parent_Type))
6982 and then Has_Discriminants (Parent_Type)
6984 Parent_Base := Base_Type (Full_View (Parent_Type));
6986 Parent_Base := Base_Type (Parent_Type);
6989 -- Before we start the previously documented transformations, here is
6990 -- little fix for size and alignment of tagged types. Normally when we
6991 -- derive type D from type P, we copy the size and alignment of P as the
6992 -- default for D, and in the absence of explicit representation clauses
6993 -- for D, the size and alignment are indeed the same as the parent.
6995 -- But this is wrong for tagged types, since fields may be added, and
6996 -- the default size may need to be larger, and the default alignment may
6997 -- need to be larger.
6999 -- We therefore reset the size and alignment fields in the tagged case.
7000 -- Note that the size and alignment will in any case be at least as
7001 -- large as the parent type (since the derived type has a copy of the
7002 -- parent type in the _parent field)
7004 -- The type is also marked as being tagged here, which is needed when
7005 -- processing components with a self-referential anonymous access type
7006 -- in the call to Check_Anonymous_Access_Components below. Note that
7007 -- this flag is also set later on for completeness.
7010 Set_Is_Tagged_Type (Derived_Type);
7011 Init_Size_Align (Derived_Type);
7014 -- STEP 0a: figure out what kind of derived type declaration we have
7016 if Private_Extension then
7018 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7021 Type_Def := Type_Definition (N);
7023 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7024 -- Parent_Base can be a private type or private extension. However,
7025 -- for tagged types with an extension the newly added fields are
7026 -- visible and hence the Derived_Type is always an E_Record_Type.
7027 -- (except that the parent may have its own private fields).
7028 -- For untagged types we preserve the Ekind of the Parent_Base.
7030 if Present (Record_Extension_Part (Type_Def)) then
7031 Set_Ekind (Derived_Type, E_Record_Type);
7033 -- Create internal access types for components with anonymous
7036 if Ada_Version >= Ada_2005 then
7037 Check_Anonymous_Access_Components
7038 (N, Derived_Type, Derived_Type,
7039 Component_List (Record_Extension_Part (Type_Def)));
7043 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7047 -- Indic can either be an N_Identifier if the subtype indication
7048 -- contains no constraint or an N_Subtype_Indication if the subtype
7049 -- indication has a constraint.
7051 Indic := Subtype_Indication (Type_Def);
7052 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7054 -- Check that the type has visible discriminants. The type may be
7055 -- a private type with unknown discriminants whose full view has
7056 -- discriminants which are invisible.
7058 if Constraint_Present then
7059 if not Has_Discriminants (Parent_Base)
7061 (Has_Unknown_Discriminants (Parent_Base)
7062 and then Is_Private_Type (Parent_Base))
7065 ("invalid constraint: type has no discriminant",
7066 Constraint (Indic));
7068 Constraint_Present := False;
7069 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7071 elsif Is_Constrained (Parent_Type) then
7073 ("invalid constraint: parent type is already constrained",
7074 Constraint (Indic));
7076 Constraint_Present := False;
7077 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7081 -- STEP 0b: If needed, apply transformation given in point 5. above
7083 if not Private_Extension
7084 and then Has_Discriminants (Parent_Type)
7085 and then not Discriminant_Specs
7086 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7088 -- First, we must analyze the constraint (see comment in point 5.)
7090 if Constraint_Present then
7091 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7093 if Has_Discriminants (Derived_Type)
7094 and then Has_Private_Declaration (Derived_Type)
7095 and then Present (Discriminant_Constraint (Derived_Type))
7097 -- Verify that constraints of the full view statically match
7098 -- those given in the partial view.
7104 C1 := First_Elmt (New_Discrs);
7105 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7106 while Present (C1) and then Present (C2) loop
7107 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7109 (Is_OK_Static_Expression (Node (C1))
7111 Is_OK_Static_Expression (Node (C2))
7113 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7119 "constraint not conformant to previous declaration",
7130 -- Insert and analyze the declaration for the unconstrained base type
7132 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7135 Make_Full_Type_Declaration (Loc,
7136 Defining_Identifier => New_Base,
7138 Make_Derived_Type_Definition (Loc,
7139 Abstract_Present => Abstract_Present (Type_Def),
7140 Limited_Present => Limited_Present (Type_Def),
7141 Subtype_Indication =>
7142 New_Occurrence_Of (Parent_Base, Loc),
7143 Record_Extension_Part =>
7144 Relocate_Node (Record_Extension_Part (Type_Def)),
7145 Interface_List => Interface_List (Type_Def)));
7147 Set_Parent (New_Decl, Parent (N));
7148 Mark_Rewrite_Insertion (New_Decl);
7149 Insert_Before (N, New_Decl);
7151 -- In the extension case, make sure ancestor is frozen appropriately
7152 -- (see also non-discriminated case below).
7154 if Present (Record_Extension_Part (Type_Def))
7155 or else Is_Interface (Parent_Base)
7157 Freeze_Before (New_Decl, Parent_Type);
7160 -- Note that this call passes False for the Derive_Subps parameter
7161 -- because subprogram derivation is deferred until after creating
7162 -- the subtype (see below).
7165 (New_Decl, Parent_Base, New_Base,
7166 Is_Completion => True, Derive_Subps => False);
7168 -- ??? This needs re-examination to determine whether the
7169 -- above call can simply be replaced by a call to Analyze.
7171 Set_Analyzed (New_Decl);
7173 -- Insert and analyze the declaration for the constrained subtype
7175 if Constraint_Present then
7177 Make_Subtype_Indication (Loc,
7178 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7179 Constraint => Relocate_Node (Constraint (Indic)));
7183 Constr_List : constant List_Id := New_List;
7188 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7189 while Present (C) loop
7192 -- It is safe here to call New_Copy_Tree since
7193 -- Force_Evaluation was called on each constraint in
7194 -- Build_Discriminant_Constraints.
7196 Append (New_Copy_Tree (Expr), To => Constr_List);
7202 Make_Subtype_Indication (Loc,
7203 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7205 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7210 Make_Subtype_Declaration (Loc,
7211 Defining_Identifier => Derived_Type,
7212 Subtype_Indication => New_Indic));
7216 -- Derivation of subprograms must be delayed until the full subtype
7217 -- has been established to ensure proper overriding of subprograms
7218 -- inherited by full types. If the derivations occurred as part of
7219 -- the call to Build_Derived_Type above, then the check for type
7220 -- conformance would fail because earlier primitive subprograms
7221 -- could still refer to the full type prior the change to the new
7222 -- subtype and hence would not match the new base type created here.
7224 Derive_Subprograms (Parent_Type, Derived_Type);
7226 -- For tagged types the Discriminant_Constraint of the new base itype
7227 -- is inherited from the first subtype so that no subtype conformance
7228 -- problem arise when the first subtype overrides primitive
7229 -- operations inherited by the implicit base type.
7232 Set_Discriminant_Constraint
7233 (New_Base, Discriminant_Constraint (Derived_Type));
7239 -- If we get here Derived_Type will have no discriminants or it will be
7240 -- a discriminated unconstrained base type.
7242 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7246 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7247 -- The declaration of a specific descendant of an interface type
7248 -- freezes the interface type (RM 13.14).
7250 if not Private_Extension or else Is_Interface (Parent_Base) then
7251 Freeze_Before (N, Parent_Type);
7254 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7255 -- cannot be declared at a deeper level than its parent type is
7256 -- removed. The check on derivation within a generic body is also
7257 -- relaxed, but there's a restriction that a derived tagged type
7258 -- cannot be declared in a generic body if it's derived directly
7259 -- or indirectly from a formal type of that generic.
7261 if Ada_Version >= Ada_2005 then
7262 if Present (Enclosing_Generic_Body (Derived_Type)) then
7264 Ancestor_Type : Entity_Id;
7267 -- Check to see if any ancestor of the derived type is a
7270 Ancestor_Type := Parent_Type;
7271 while not Is_Generic_Type (Ancestor_Type)
7272 and then Etype (Ancestor_Type) /= Ancestor_Type
7274 Ancestor_Type := Etype (Ancestor_Type);
7277 -- If the derived type does have a formal type as an
7278 -- ancestor, then it's an error if the derived type is
7279 -- declared within the body of the generic unit that
7280 -- declares the formal type in its generic formal part. It's
7281 -- sufficient to check whether the ancestor type is declared
7282 -- inside the same generic body as the derived type (such as
7283 -- within a nested generic spec), in which case the
7284 -- derivation is legal. If the formal type is declared
7285 -- outside of that generic body, then it's guaranteed that
7286 -- the derived type is declared within the generic body of
7287 -- the generic unit declaring the formal type.
7289 if Is_Generic_Type (Ancestor_Type)
7290 and then Enclosing_Generic_Body (Ancestor_Type) /=
7291 Enclosing_Generic_Body (Derived_Type)
7294 ("parent type of& must not be descendant of formal type"
7295 & " of an enclosing generic body",
7296 Indic, Derived_Type);
7301 elsif Type_Access_Level (Derived_Type) /=
7302 Type_Access_Level (Parent_Type)
7303 and then not Is_Generic_Type (Derived_Type)
7305 if Is_Controlled (Parent_Type) then
7307 ("controlled type must be declared at the library level",
7311 ("type extension at deeper accessibility level than parent",
7317 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7321 and then GB /= Enclosing_Generic_Body (Parent_Base)
7324 ("parent type of& must not be outside generic body"
7326 Indic, Derived_Type);
7332 -- Ada 2005 (AI-251)
7334 if Ada_Version >= Ada_2005 and then Is_Tagged then
7336 -- "The declaration of a specific descendant of an interface type
7337 -- freezes the interface type" (RM 13.14).
7342 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7343 Iface := First (Interface_List (Type_Def));
7344 while Present (Iface) loop
7345 Freeze_Before (N, Etype (Iface));
7352 -- STEP 1b : preliminary cleanup of the full view of private types
7354 -- If the type is already marked as having discriminants, then it's the
7355 -- completion of a private type or private extension and we need to
7356 -- retain the discriminants from the partial view if the current
7357 -- declaration has Discriminant_Specifications so that we can verify
7358 -- conformance. However, we must remove any existing components that
7359 -- were inherited from the parent (and attached in Copy_And_Swap)
7360 -- because the full type inherits all appropriate components anyway, and
7361 -- we do not want the partial view's components interfering.
7363 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7364 Discrim := First_Discriminant (Derived_Type);
7366 Last_Discrim := Discrim;
7367 Next_Discriminant (Discrim);
7368 exit when No (Discrim);
7371 Set_Last_Entity (Derived_Type, Last_Discrim);
7373 -- In all other cases wipe out the list of inherited components (even
7374 -- inherited discriminants), it will be properly rebuilt here.
7377 Set_First_Entity (Derived_Type, Empty);
7378 Set_Last_Entity (Derived_Type, Empty);
7381 -- STEP 1c: Initialize some flags for the Derived_Type
7383 -- The following flags must be initialized here so that
7384 -- Process_Discriminants can check that discriminants of tagged types do
7385 -- not have a default initial value and that access discriminants are
7386 -- only specified for limited records. For completeness, these flags are
7387 -- also initialized along with all the other flags below.
7389 -- AI-419: Limitedness is not inherited from an interface parent, so to
7390 -- be limited in that case the type must be explicitly declared as
7391 -- limited. However, task and protected interfaces are always limited.
7393 if Limited_Present (Type_Def) then
7394 Set_Is_Limited_Record (Derived_Type);
7396 elsif Is_Limited_Record (Parent_Type)
7397 or else (Present (Full_View (Parent_Type))
7398 and then Is_Limited_Record (Full_View (Parent_Type)))
7400 if not Is_Interface (Parent_Type)
7401 or else Is_Synchronized_Interface (Parent_Type)
7402 or else Is_Protected_Interface (Parent_Type)
7403 or else Is_Task_Interface (Parent_Type)
7405 Set_Is_Limited_Record (Derived_Type);
7409 -- STEP 2a: process discriminants of derived type if any
7411 Push_Scope (Derived_Type);
7413 if Discriminant_Specs then
7414 Set_Has_Unknown_Discriminants (Derived_Type, False);
7416 -- The following call initializes fields Has_Discriminants and
7417 -- Discriminant_Constraint, unless we are processing the completion
7418 -- of a private type declaration.
7420 Check_Or_Process_Discriminants (N, Derived_Type);
7422 -- For untagged types, the constraint on the Parent_Type must be
7423 -- present and is used to rename the discriminants.
7425 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7426 Error_Msg_N ("untagged parent must have discriminants", Indic);
7428 elsif not Is_Tagged and then not Constraint_Present then
7430 ("discriminant constraint needed for derived untagged records",
7433 -- Otherwise the parent subtype must be constrained unless we have a
7434 -- private extension.
7436 elsif not Constraint_Present
7437 and then not Private_Extension
7438 and then not Is_Constrained (Parent_Type)
7441 ("unconstrained type not allowed in this context", Indic);
7443 elsif Constraint_Present then
7444 -- The following call sets the field Corresponding_Discriminant
7445 -- for the discriminants in the Derived_Type.
7447 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7449 -- For untagged types all new discriminants must rename
7450 -- discriminants in the parent. For private extensions new
7451 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7453 Discrim := First_Discriminant (Derived_Type);
7454 while Present (Discrim) loop
7456 and then No (Corresponding_Discriminant (Discrim))
7459 ("new discriminants must constrain old ones", Discrim);
7461 elsif Private_Extension
7462 and then Present (Corresponding_Discriminant (Discrim))
7465 ("only static constraints allowed for parent"
7466 & " discriminants in the partial view", Indic);
7470 -- If a new discriminant is used in the constraint, then its
7471 -- subtype must be statically compatible with the parent
7472 -- discriminant's subtype (3.7(15)).
7474 if Present (Corresponding_Discriminant (Discrim))
7476 not Subtypes_Statically_Compatible
7478 Etype (Corresponding_Discriminant (Discrim)))
7481 ("subtype must be compatible with parent discriminant",
7485 Next_Discriminant (Discrim);
7488 -- Check whether the constraints of the full view statically
7489 -- match those imposed by the parent subtype [7.3(13)].
7491 if Present (Stored_Constraint (Derived_Type)) then
7496 C1 := First_Elmt (Discs);
7497 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7498 while Present (C1) and then Present (C2) loop
7500 Fully_Conformant_Expressions (Node (C1), Node (C2))
7503 ("not conformant with previous declaration",
7514 -- STEP 2b: No new discriminants, inherit discriminants if any
7517 if Private_Extension then
7518 Set_Has_Unknown_Discriminants
7520 Has_Unknown_Discriminants (Parent_Type)
7521 or else Unknown_Discriminants_Present (N));
7523 -- The partial view of the parent may have unknown discriminants,
7524 -- but if the full view has discriminants and the parent type is
7525 -- in scope they must be inherited.
7527 elsif Has_Unknown_Discriminants (Parent_Type)
7529 (not Has_Discriminants (Parent_Type)
7530 or else not In_Open_Scopes (Scope (Parent_Type)))
7532 Set_Has_Unknown_Discriminants (Derived_Type);
7535 if not Has_Unknown_Discriminants (Derived_Type)
7536 and then not Has_Unknown_Discriminants (Parent_Base)
7537 and then Has_Discriminants (Parent_Type)
7539 Inherit_Discrims := True;
7540 Set_Has_Discriminants
7541 (Derived_Type, True);
7542 Set_Discriminant_Constraint
7543 (Derived_Type, Discriminant_Constraint (Parent_Base));
7546 -- The following test is true for private types (remember
7547 -- transformation 5. is not applied to those) and in an error
7550 if Constraint_Present then
7551 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7554 -- For now mark a new derived type as constrained only if it has no
7555 -- discriminants. At the end of Build_Derived_Record_Type we properly
7556 -- set this flag in the case of private extensions. See comments in
7557 -- point 9. just before body of Build_Derived_Record_Type.
7561 not (Inherit_Discrims
7562 or else Has_Unknown_Discriminants (Derived_Type)));
7565 -- STEP 3: initialize fields of derived type
7567 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7568 Set_Stored_Constraint (Derived_Type, No_Elist);
7570 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7571 -- but cannot be interfaces
7573 if not Private_Extension
7574 and then Ekind (Derived_Type) /= E_Private_Type
7575 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7577 if Interface_Present (Type_Def) then
7578 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7581 Set_Interfaces (Derived_Type, No_Elist);
7584 -- Fields inherited from the Parent_Type
7587 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7588 Set_Has_Specified_Layout
7589 (Derived_Type, Has_Specified_Layout (Parent_Type));
7590 Set_Is_Limited_Composite
7591 (Derived_Type, Is_Limited_Composite (Parent_Type));
7592 Set_Is_Private_Composite
7593 (Derived_Type, Is_Private_Composite (Parent_Type));
7595 -- Fields inherited from the Parent_Base
7597 Set_Has_Controlled_Component
7598 (Derived_Type, Has_Controlled_Component (Parent_Base));
7599 Set_Has_Non_Standard_Rep
7600 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7601 Set_Has_Primitive_Operations
7602 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7604 -- Fields inherited from the Parent_Base in the non-private case
7606 if Ekind (Derived_Type) = E_Record_Type then
7607 Set_Has_Complex_Representation
7608 (Derived_Type, Has_Complex_Representation (Parent_Base));
7611 -- Fields inherited from the Parent_Base for record types
7613 if Is_Record_Type (Derived_Type) then
7615 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7616 -- Parent_Base can be a private type or private extension.
7618 if Present (Full_View (Parent_Base)) then
7619 Set_OK_To_Reorder_Components
7621 OK_To_Reorder_Components (Full_View (Parent_Base)));
7622 Set_Reverse_Bit_Order
7623 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7625 Set_OK_To_Reorder_Components
7626 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7627 Set_Reverse_Bit_Order
7628 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7632 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7634 if not Is_Controlled (Parent_Type) then
7635 Set_Finalize_Storage_Only
7636 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7639 -- Set fields for private derived types
7641 if Is_Private_Type (Derived_Type) then
7642 Set_Depends_On_Private (Derived_Type, True);
7643 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7645 -- Inherit fields from non private record types. If this is the
7646 -- completion of a derivation from a private type, the parent itself
7647 -- is private, and the attributes come from its full view, which must
7651 if Is_Private_Type (Parent_Base)
7652 and then not Is_Record_Type (Parent_Base)
7654 Set_Component_Alignment
7655 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7657 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7659 Set_Component_Alignment
7660 (Derived_Type, Component_Alignment (Parent_Base));
7662 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7666 -- Set fields for tagged types
7669 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7671 -- All tagged types defined in Ada.Finalization are controlled
7673 if Chars (Scope (Derived_Type)) = Name_Finalization
7674 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7675 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7677 Set_Is_Controlled (Derived_Type);
7679 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7682 -- Minor optimization: there is no need to generate the class-wide
7683 -- entity associated with an underlying record view.
7685 if not Is_Underlying_Record_View (Derived_Type) then
7686 Make_Class_Wide_Type (Derived_Type);
7689 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7691 if Has_Discriminants (Derived_Type)
7692 and then Constraint_Present
7694 Set_Stored_Constraint
7695 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7698 if Ada_Version >= Ada_2005 then
7700 Ifaces_List : Elist_Id;
7703 -- Checks rules 3.9.4 (13/2 and 14/2)
7705 if Comes_From_Source (Derived_Type)
7706 and then not Is_Private_Type (Derived_Type)
7707 and then Is_Interface (Parent_Type)
7708 and then not Is_Interface (Derived_Type)
7710 if Is_Task_Interface (Parent_Type) then
7712 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7715 elsif Is_Protected_Interface (Parent_Type) then
7717 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7722 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7724 Check_Interfaces (N, Type_Def);
7726 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7727 -- not already in the parents.
7731 Ifaces_List => Ifaces_List,
7732 Exclude_Parents => True);
7734 Set_Interfaces (Derived_Type, Ifaces_List);
7736 -- If the derived type is the anonymous type created for
7737 -- a declaration whose parent has a constraint, propagate
7738 -- the interface list to the source type. This must be done
7739 -- prior to the completion of the analysis of the source type
7740 -- because the components in the extension may contain current
7741 -- instances whose legality depends on some ancestor.
7743 if Is_Itype (Derived_Type) then
7745 Def : constant Node_Id :=
7746 Associated_Node_For_Itype (Derived_Type);
7749 and then Nkind (Def) = N_Full_Type_Declaration
7752 (Defining_Identifier (Def), Ifaces_List);
7760 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7761 Set_Has_Non_Standard_Rep
7762 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7765 -- STEP 4: Inherit components from the parent base and constrain them.
7766 -- Apply the second transformation described in point 6. above.
7768 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7769 or else not Has_Discriminants (Parent_Type)
7770 or else not Is_Constrained (Parent_Type)
7774 Constrs := Discriminant_Constraint (Parent_Type);
7779 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7781 -- STEP 5a: Copy the parent record declaration for untagged types
7783 if not Is_Tagged then
7785 -- Discriminant_Constraint (Derived_Type) has been properly
7786 -- constructed. Save it and temporarily set it to Empty because we
7787 -- do not want the call to New_Copy_Tree below to mess this list.
7789 if Has_Discriminants (Derived_Type) then
7790 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7791 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7793 Save_Discr_Constr := No_Elist;
7796 -- Save the Etype field of Derived_Type. It is correctly set now,
7797 -- but the call to New_Copy tree may remap it to point to itself,
7798 -- which is not what we want. Ditto for the Next_Entity field.
7800 Save_Etype := Etype (Derived_Type);
7801 Save_Next_Entity := Next_Entity (Derived_Type);
7803 -- Assoc_List maps all stored discriminants in the Parent_Base to
7804 -- stored discriminants in the Derived_Type. It is fundamental that
7805 -- no types or itypes with discriminants other than the stored
7806 -- discriminants appear in the entities declared inside
7807 -- Derived_Type, since the back end cannot deal with it.
7811 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7813 -- Restore the fields saved prior to the New_Copy_Tree call
7814 -- and compute the stored constraint.
7816 Set_Etype (Derived_Type, Save_Etype);
7817 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7819 if Has_Discriminants (Derived_Type) then
7820 Set_Discriminant_Constraint
7821 (Derived_Type, Save_Discr_Constr);
7822 Set_Stored_Constraint
7823 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7824 Replace_Components (Derived_Type, New_Decl);
7827 -- Insert the new derived type declaration
7829 Rewrite (N, New_Decl);
7831 -- STEP 5b: Complete the processing for record extensions in generics
7833 -- There is no completion for record extensions declared in the
7834 -- parameter part of a generic, so we need to complete processing for
7835 -- these generic record extensions here. The Record_Type_Definition call
7836 -- will change the Ekind of the components from E_Void to E_Component.
7838 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7839 Record_Type_Definition (Empty, Derived_Type);
7841 -- STEP 5c: Process the record extension for non private tagged types
7843 elsif not Private_Extension then
7845 -- Add the _parent field in the derived type
7847 Expand_Record_Extension (Derived_Type, Type_Def);
7849 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7850 -- implemented interfaces if we are in expansion mode
7853 and then Has_Interfaces (Derived_Type)
7855 Add_Interface_Tag_Components (N, Derived_Type);
7858 -- Analyze the record extension
7860 Record_Type_Definition
7861 (Record_Extension_Part (Type_Def), Derived_Type);
7866 -- Nothing else to do if there is an error in the derivation.
7867 -- An unusual case: the full view may be derived from a type in an
7868 -- instance, when the partial view was used illegally as an actual
7869 -- in that instance, leading to a circular definition.
7871 if Etype (Derived_Type) = Any_Type
7872 or else Etype (Parent_Type) = Derived_Type
7877 -- Set delayed freeze and then derive subprograms, we need to do
7878 -- this in this order so that derived subprograms inherit the
7879 -- derived freeze if necessary.
7881 Set_Has_Delayed_Freeze (Derived_Type);
7883 if Derive_Subps then
7884 Derive_Subprograms (Parent_Type, Derived_Type);
7887 -- If we have a private extension which defines a constrained derived
7888 -- type mark as constrained here after we have derived subprograms. See
7889 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7891 if Private_Extension and then Inherit_Discrims then
7892 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7893 Set_Is_Constrained (Derived_Type, True);
7894 Set_Discriminant_Constraint (Derived_Type, Discs);
7896 elsif Is_Constrained (Parent_Type) then
7898 (Derived_Type, True);
7899 Set_Discriminant_Constraint
7900 (Derived_Type, Discriminant_Constraint (Parent_Type));
7904 -- Update the class-wide type, which shares the now-completed entity
7905 -- list with its specific type. In case of underlying record views,
7906 -- we do not generate the corresponding class wide entity.
7909 and then not Is_Underlying_Record_View (Derived_Type)
7912 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7914 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7917 -- Update the scope of anonymous access types of discriminants and other
7918 -- components, to prevent scope anomalies in gigi, when the derivation
7919 -- appears in a scope nested within that of the parent.
7925 D := First_Entity (Derived_Type);
7926 while Present (D) loop
7927 if Ekind_In (D, E_Discriminant, E_Component) then
7928 if Is_Itype (Etype (D))
7929 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7931 Set_Scope (Etype (D), Current_Scope);
7938 end Build_Derived_Record_Type;
7940 ------------------------
7941 -- Build_Derived_Type --
7942 ------------------------
7944 procedure Build_Derived_Type
7946 Parent_Type : Entity_Id;
7947 Derived_Type : Entity_Id;
7948 Is_Completion : Boolean;
7949 Derive_Subps : Boolean := True)
7951 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7954 -- Set common attributes
7956 Set_Scope (Derived_Type, Current_Scope);
7958 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7959 Set_Etype (Derived_Type, Parent_Base);
7960 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
7962 Set_Size_Info (Derived_Type, Parent_Type);
7963 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
7964 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7965 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
7967 -- If the parent type is a private subtype, the convention on the base
7968 -- type may be set in the private part, and not propagated to the
7969 -- subtype until later, so we obtain the convention from the base type.
7971 Set_Convention (Derived_Type, Convention (Parent_Base));
7973 -- Propagate invariant information. The new type has invariants if
7974 -- they are inherited from the parent type, and these invariants can
7975 -- be further inherited, so both flags are set.
7977 if Has_Inheritable_Invariants (Parent_Type) then
7978 Set_Has_Inheritable_Invariants (Derived_Type);
7979 Set_Has_Invariants (Derived_Type);
7982 -- We similarly inherit predicates
7984 if Has_Predicates (Parent_Type) then
7985 Set_Has_Predicates (Derived_Type);
7988 -- The derived type inherits the representation clauses of the parent.
7989 -- However, for a private type that is completed by a derivation, there
7990 -- may be operation attributes that have been specified already (stream
7991 -- attributes and External_Tag) and those must be provided. Finally,
7992 -- if the partial view is a private extension, the representation items
7993 -- of the parent have been inherited already, and should not be chained
7994 -- twice to the derived type.
7996 if Is_Tagged_Type (Parent_Type)
7997 and then Present (First_Rep_Item (Derived_Type))
7999 -- The existing items are either operational items or items inherited
8000 -- from a private extension declaration.
8004 -- Used to iterate over representation items of the derived type
8007 -- Last representation item of the (non-empty) representation
8008 -- item list of the derived type.
8010 Found : Boolean := False;
8013 Rep := First_Rep_Item (Derived_Type);
8015 while Present (Rep) loop
8016 if Rep = First_Rep_Item (Parent_Type) then
8021 Rep := Next_Rep_Item (Rep);
8023 if Present (Rep) then
8029 -- Here if we either encountered the parent type's first rep
8030 -- item on the derived type's rep item list (in which case
8031 -- Found is True, and we have nothing else to do), or if we
8032 -- reached the last rep item of the derived type, which is
8033 -- Last_Rep, in which case we further chain the parent type's
8034 -- rep items to those of the derived type.
8037 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8042 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8045 case Ekind (Parent_Type) is
8046 when Numeric_Kind =>
8047 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8050 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8054 | Class_Wide_Kind =>
8055 Build_Derived_Record_Type
8056 (N, Parent_Type, Derived_Type, Derive_Subps);
8059 when Enumeration_Kind =>
8060 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8063 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8065 when Incomplete_Or_Private_Kind =>
8066 Build_Derived_Private_Type
8067 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8069 -- For discriminated types, the derivation includes deriving
8070 -- primitive operations. For others it is done below.
8072 if Is_Tagged_Type (Parent_Type)
8073 or else Has_Discriminants (Parent_Type)
8074 or else (Present (Full_View (Parent_Type))
8075 and then Has_Discriminants (Full_View (Parent_Type)))
8080 when Concurrent_Kind =>
8081 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8084 raise Program_Error;
8087 if Etype (Derived_Type) = Any_Type then
8091 -- Set delayed freeze and then derive subprograms, we need to do this
8092 -- in this order so that derived subprograms inherit the derived freeze
8095 Set_Has_Delayed_Freeze (Derived_Type);
8096 if Derive_Subps then
8097 Derive_Subprograms (Parent_Type, Derived_Type);
8100 Set_Has_Primitive_Operations
8101 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8102 end Build_Derived_Type;
8104 -----------------------
8105 -- Build_Discriminal --
8106 -----------------------
8108 procedure Build_Discriminal (Discrim : Entity_Id) is
8109 D_Minal : Entity_Id;
8110 CR_Disc : Entity_Id;
8113 -- A discriminal has the same name as the discriminant
8115 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8117 Set_Ekind (D_Minal, E_In_Parameter);
8118 Set_Mechanism (D_Minal, Default_Mechanism);
8119 Set_Etype (D_Minal, Etype (Discrim));
8120 Set_Scope (D_Minal, Current_Scope);
8122 Set_Discriminal (Discrim, D_Minal);
8123 Set_Discriminal_Link (D_Minal, Discrim);
8125 -- For task types, build at once the discriminants of the corresponding
8126 -- record, which are needed if discriminants are used in entry defaults
8127 -- and in family bounds.
8129 if Is_Concurrent_Type (Current_Scope)
8130 or else Is_Limited_Type (Current_Scope)
8132 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8134 Set_Ekind (CR_Disc, E_In_Parameter);
8135 Set_Mechanism (CR_Disc, Default_Mechanism);
8136 Set_Etype (CR_Disc, Etype (Discrim));
8137 Set_Scope (CR_Disc, Current_Scope);
8138 Set_Discriminal_Link (CR_Disc, Discrim);
8139 Set_CR_Discriminant (Discrim, CR_Disc);
8141 end Build_Discriminal;
8143 ------------------------------------
8144 -- Build_Discriminant_Constraints --
8145 ------------------------------------
8147 function Build_Discriminant_Constraints
8150 Derived_Def : Boolean := False) return Elist_Id
8152 C : constant Node_Id := Constraint (Def);
8153 Nb_Discr : constant Nat := Number_Discriminants (T);
8155 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8156 -- Saves the expression corresponding to a given discriminant in T
8158 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8159 -- Return the Position number within array Discr_Expr of a discriminant
8160 -- D within the discriminant list of the discriminated type T.
8166 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8170 Disc := First_Discriminant (T);
8171 for J in Discr_Expr'Range loop
8176 Next_Discriminant (Disc);
8179 -- Note: Since this function is called on discriminants that are
8180 -- known to belong to the discriminated type, falling through the
8181 -- loop with no match signals an internal compiler error.
8183 raise Program_Error;
8186 -- Declarations local to Build_Discriminant_Constraints
8190 Elist : constant Elist_Id := New_Elmt_List;
8198 Discrim_Present : Boolean := False;
8200 -- Start of processing for Build_Discriminant_Constraints
8203 -- The following loop will process positional associations only.
8204 -- For a positional association, the (single) discriminant is
8205 -- implicitly specified by position, in textual order (RM 3.7.2).
8207 Discr := First_Discriminant (T);
8208 Constr := First (Constraints (C));
8209 for D in Discr_Expr'Range loop
8210 exit when Nkind (Constr) = N_Discriminant_Association;
8213 Error_Msg_N ("too few discriminants given in constraint", C);
8214 return New_Elmt_List;
8216 elsif Nkind (Constr) = N_Range
8217 or else (Nkind (Constr) = N_Attribute_Reference
8219 Attribute_Name (Constr) = Name_Range)
8222 ("a range is not a valid discriminant constraint", Constr);
8223 Discr_Expr (D) := Error;
8226 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8227 Discr_Expr (D) := Constr;
8230 Next_Discriminant (Discr);
8234 if No (Discr) and then Present (Constr) then
8235 Error_Msg_N ("too many discriminants given in constraint", Constr);
8236 return New_Elmt_List;
8239 -- Named associations can be given in any order, but if both positional
8240 -- and named associations are used in the same discriminant constraint,
8241 -- then positional associations must occur first, at their normal
8242 -- position. Hence once a named association is used, the rest of the
8243 -- discriminant constraint must use only named associations.
8245 while Present (Constr) loop
8247 -- Positional association forbidden after a named association
8249 if Nkind (Constr) /= N_Discriminant_Association then
8250 Error_Msg_N ("positional association follows named one", Constr);
8251 return New_Elmt_List;
8253 -- Otherwise it is a named association
8256 -- E records the type of the discriminants in the named
8257 -- association. All the discriminants specified in the same name
8258 -- association must have the same type.
8262 -- Search the list of discriminants in T to see if the simple name
8263 -- given in the constraint matches any of them.
8265 Id := First (Selector_Names (Constr));
8266 while Present (Id) loop
8269 -- If Original_Discriminant is present, we are processing a
8270 -- generic instantiation and this is an instance node. We need
8271 -- to find the name of the corresponding discriminant in the
8272 -- actual record type T and not the name of the discriminant in
8273 -- the generic formal. Example:
8276 -- type G (D : int) is private;
8278 -- subtype W is G (D => 1);
8280 -- type Rec (X : int) is record ... end record;
8281 -- package Q is new P (G => Rec);
8283 -- At the point of the instantiation, formal type G is Rec
8284 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8285 -- which really looks like "subtype W is Rec (D => 1);" at
8286 -- the point of instantiation, we want to find the discriminant
8287 -- that corresponds to D in Rec, i.e. X.
8289 if Present (Original_Discriminant (Id)) then
8290 Discr := Find_Corresponding_Discriminant (Id, T);
8294 Discr := First_Discriminant (T);
8295 while Present (Discr) loop
8296 if Chars (Discr) = Chars (Id) then
8301 Next_Discriminant (Discr);
8305 Error_Msg_N ("& does not match any discriminant", Id);
8306 return New_Elmt_List;
8308 -- The following is only useful for the benefit of generic
8309 -- instances but it does not interfere with other
8310 -- processing for the non-generic case so we do it in all
8311 -- cases (for generics this statement is executed when
8312 -- processing the generic definition, see comment at the
8313 -- beginning of this if statement).
8316 Set_Original_Discriminant (Id, Discr);
8320 Position := Pos_Of_Discr (T, Discr);
8322 if Present (Discr_Expr (Position)) then
8323 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8326 -- Each discriminant specified in the same named association
8327 -- must be associated with a separate copy of the
8328 -- corresponding expression.
8330 if Present (Next (Id)) then
8331 Expr := New_Copy_Tree (Expression (Constr));
8332 Set_Parent (Expr, Parent (Expression (Constr)));
8334 Expr := Expression (Constr);
8337 Discr_Expr (Position) := Expr;
8338 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8341 -- A discriminant association with more than one discriminant
8342 -- name is only allowed if the named discriminants are all of
8343 -- the same type (RM 3.7.1(8)).
8346 E := Base_Type (Etype (Discr));
8348 elsif Base_Type (Etype (Discr)) /= E then
8350 ("all discriminants in an association " &
8351 "must have the same type", Id);
8361 -- A discriminant constraint must provide exactly one value for each
8362 -- discriminant of the type (RM 3.7.1(8)).
8364 for J in Discr_Expr'Range loop
8365 if No (Discr_Expr (J)) then
8366 Error_Msg_N ("too few discriminants given in constraint", C);
8367 return New_Elmt_List;
8371 -- Determine if there are discriminant expressions in the constraint
8373 for J in Discr_Expr'Range loop
8374 if Denotes_Discriminant
8375 (Discr_Expr (J), Check_Concurrent => True)
8377 Discrim_Present := True;
8381 -- Build an element list consisting of the expressions given in the
8382 -- discriminant constraint and apply the appropriate checks. The list
8383 -- is constructed after resolving any named discriminant associations
8384 -- and therefore the expressions appear in the textual order of the
8387 Discr := First_Discriminant (T);
8388 for J in Discr_Expr'Range loop
8389 if Discr_Expr (J) /= Error then
8390 Append_Elmt (Discr_Expr (J), Elist);
8392 -- If any of the discriminant constraints is given by a
8393 -- discriminant and we are in a derived type declaration we
8394 -- have a discriminant renaming. Establish link between new
8395 -- and old discriminant.
8397 if Denotes_Discriminant (Discr_Expr (J)) then
8399 Set_Corresponding_Discriminant
8400 (Entity (Discr_Expr (J)), Discr);
8403 -- Force the evaluation of non-discriminant expressions.
8404 -- If we have found a discriminant in the constraint 3.4(26)
8405 -- and 3.8(18) demand that no range checks are performed are
8406 -- after evaluation. If the constraint is for a component
8407 -- definition that has a per-object constraint, expressions are
8408 -- evaluated but not checked either. In all other cases perform
8412 if Discrim_Present then
8415 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8417 Has_Per_Object_Constraint
8418 (Defining_Identifier (Parent (Parent (Def))))
8422 elsif Is_Access_Type (Etype (Discr)) then
8423 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8426 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8429 Force_Evaluation (Discr_Expr (J));
8432 -- Check that the designated type of an access discriminant's
8433 -- expression is not a class-wide type unless the discriminant's
8434 -- designated type is also class-wide.
8436 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8437 and then not Is_Class_Wide_Type
8438 (Designated_Type (Etype (Discr)))
8439 and then Etype (Discr_Expr (J)) /= Any_Type
8440 and then Is_Class_Wide_Type
8441 (Designated_Type (Etype (Discr_Expr (J))))
8443 Wrong_Type (Discr_Expr (J), Etype (Discr));
8445 elsif Is_Access_Type (Etype (Discr))
8446 and then not Is_Access_Constant (Etype (Discr))
8447 and then Is_Access_Type (Etype (Discr_Expr (J)))
8448 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8451 ("constraint for discriminant& must be access to variable",
8456 Next_Discriminant (Discr);
8460 end Build_Discriminant_Constraints;
8462 ---------------------------------
8463 -- Build_Discriminated_Subtype --
8464 ---------------------------------
8466 procedure Build_Discriminated_Subtype
8470 Related_Nod : Node_Id;
8471 For_Access : Boolean := False)
8473 Has_Discrs : constant Boolean := Has_Discriminants (T);
8474 Constrained : constant Boolean :=
8476 and then not Is_Empty_Elmt_List (Elist)
8477 and then not Is_Class_Wide_Type (T))
8478 or else Is_Constrained (T);
8481 if Ekind (T) = E_Record_Type then
8483 Set_Ekind (Def_Id, E_Private_Subtype);
8484 Set_Is_For_Access_Subtype (Def_Id, True);
8486 Set_Ekind (Def_Id, E_Record_Subtype);
8489 -- Inherit preelaboration flag from base, for types for which it
8490 -- may have been set: records, private types, protected types.
8492 Set_Known_To_Have_Preelab_Init
8493 (Def_Id, Known_To_Have_Preelab_Init (T));
8495 elsif Ekind (T) = E_Task_Type then
8496 Set_Ekind (Def_Id, E_Task_Subtype);
8498 elsif Ekind (T) = E_Protected_Type then
8499 Set_Ekind (Def_Id, E_Protected_Subtype);
8500 Set_Known_To_Have_Preelab_Init
8501 (Def_Id, Known_To_Have_Preelab_Init (T));
8503 elsif Is_Private_Type (T) then
8504 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8505 Set_Known_To_Have_Preelab_Init
8506 (Def_Id, Known_To_Have_Preelab_Init (T));
8508 elsif Is_Class_Wide_Type (T) then
8509 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8512 -- Incomplete type. Attach subtype to list of dependents, to be
8513 -- completed with full view of parent type, unless is it the
8514 -- designated subtype of a record component within an init_proc.
8515 -- This last case arises for a component of an access type whose
8516 -- designated type is incomplete (e.g. a Taft Amendment type).
8517 -- The designated subtype is within an inner scope, and needs no
8518 -- elaboration, because only the access type is needed in the
8519 -- initialization procedure.
8521 Set_Ekind (Def_Id, Ekind (T));
8523 if For_Access and then Within_Init_Proc then
8526 Append_Elmt (Def_Id, Private_Dependents (T));
8530 Set_Etype (Def_Id, T);
8531 Init_Size_Align (Def_Id);
8532 Set_Has_Discriminants (Def_Id, Has_Discrs);
8533 Set_Is_Constrained (Def_Id, Constrained);
8535 Set_First_Entity (Def_Id, First_Entity (T));
8536 Set_Last_Entity (Def_Id, Last_Entity (T));
8538 -- If the subtype is the completion of a private declaration, there may
8539 -- have been representation clauses for the partial view, and they must
8540 -- be preserved. Build_Derived_Type chains the inherited clauses with
8541 -- the ones appearing on the extension. If this comes from a subtype
8542 -- declaration, all clauses are inherited.
8544 if No (First_Rep_Item (Def_Id)) then
8545 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8548 if Is_Tagged_Type (T) then
8549 Set_Is_Tagged_Type (Def_Id);
8550 Make_Class_Wide_Type (Def_Id);
8553 Set_Stored_Constraint (Def_Id, No_Elist);
8556 Set_Discriminant_Constraint (Def_Id, Elist);
8557 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8560 if Is_Tagged_Type (T) then
8562 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8563 -- concurrent record type (which has the list of primitive
8566 if Ada_Version >= Ada_2005
8567 and then Is_Concurrent_Type (T)
8569 Set_Corresponding_Record_Type (Def_Id,
8570 Corresponding_Record_Type (T));
8572 Set_Direct_Primitive_Operations (Def_Id,
8573 Direct_Primitive_Operations (T));
8576 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8579 -- Subtypes introduced by component declarations do not need to be
8580 -- marked as delayed, and do not get freeze nodes, because the semantics
8581 -- verifies that the parents of the subtypes are frozen before the
8582 -- enclosing record is frozen.
8584 if not Is_Type (Scope (Def_Id)) then
8585 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8587 if Is_Private_Type (T)
8588 and then Present (Full_View (T))
8590 Conditional_Delay (Def_Id, Full_View (T));
8592 Conditional_Delay (Def_Id, T);
8596 if Is_Record_Type (T) then
8597 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8600 and then not Is_Empty_Elmt_List (Elist)
8601 and then not For_Access
8603 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8604 elsif not For_Access then
8605 Set_Cloned_Subtype (Def_Id, T);
8608 end Build_Discriminated_Subtype;
8610 ---------------------------
8611 -- Build_Itype_Reference --
8612 ---------------------------
8614 procedure Build_Itype_Reference
8618 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8620 Set_Itype (IR, Ityp);
8621 Insert_After (Nod, IR);
8622 end Build_Itype_Reference;
8624 ------------------------
8625 -- Build_Scalar_Bound --
8626 ------------------------
8628 function Build_Scalar_Bound
8631 Der_T : Entity_Id) return Node_Id
8633 New_Bound : Entity_Id;
8636 -- Note: not clear why this is needed, how can the original bound
8637 -- be unanalyzed at this point? and if it is, what business do we
8638 -- have messing around with it? and why is the base type of the
8639 -- parent type the right type for the resolution. It probably is
8640 -- not! It is OK for the new bound we are creating, but not for
8641 -- the old one??? Still if it never happens, no problem!
8643 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8645 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8646 New_Bound := New_Copy (Bound);
8647 Set_Etype (New_Bound, Der_T);
8648 Set_Analyzed (New_Bound);
8650 elsif Is_Entity_Name (Bound) then
8651 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8653 -- The following is almost certainly wrong. What business do we have
8654 -- relocating a node (Bound) that is presumably still attached to
8655 -- the tree elsewhere???
8658 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8661 Set_Etype (New_Bound, Der_T);
8663 end Build_Scalar_Bound;
8665 --------------------------------
8666 -- Build_Underlying_Full_View --
8667 --------------------------------
8669 procedure Build_Underlying_Full_View
8674 Loc : constant Source_Ptr := Sloc (N);
8675 Subt : constant Entity_Id :=
8676 Make_Defining_Identifier
8677 (Loc, New_External_Name (Chars (Typ), 'S'));
8684 procedure Set_Discriminant_Name (Id : Node_Id);
8685 -- If the derived type has discriminants, they may rename discriminants
8686 -- of the parent. When building the full view of the parent, we need to
8687 -- recover the names of the original discriminants if the constraint is
8688 -- given by named associations.
8690 ---------------------------
8691 -- Set_Discriminant_Name --
8692 ---------------------------
8694 procedure Set_Discriminant_Name (Id : Node_Id) is
8698 Set_Original_Discriminant (Id, Empty);
8700 if Has_Discriminants (Typ) then
8701 Disc := First_Discriminant (Typ);
8702 while Present (Disc) loop
8703 if Chars (Disc) = Chars (Id)
8704 and then Present (Corresponding_Discriminant (Disc))
8706 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8708 Next_Discriminant (Disc);
8711 end Set_Discriminant_Name;
8713 -- Start of processing for Build_Underlying_Full_View
8716 if Nkind (N) = N_Full_Type_Declaration then
8717 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8719 elsif Nkind (N) = N_Subtype_Declaration then
8720 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8722 elsif Nkind (N) = N_Component_Declaration then
8725 (Constraint (Subtype_Indication (Component_Definition (N))));
8728 raise Program_Error;
8731 C := First (Constraints (Constr));
8732 while Present (C) loop
8733 if Nkind (C) = N_Discriminant_Association then
8734 Id := First (Selector_Names (C));
8735 while Present (Id) loop
8736 Set_Discriminant_Name (Id);
8745 Make_Subtype_Declaration (Loc,
8746 Defining_Identifier => Subt,
8747 Subtype_Indication =>
8748 Make_Subtype_Indication (Loc,
8749 Subtype_Mark => New_Reference_To (Par, Loc),
8750 Constraint => New_Copy_Tree (Constr)));
8752 -- If this is a component subtype for an outer itype, it is not
8753 -- a list member, so simply set the parent link for analysis: if
8754 -- the enclosing type does not need to be in a declarative list,
8755 -- neither do the components.
8757 if Is_List_Member (N)
8758 and then Nkind (N) /= N_Component_Declaration
8760 Insert_Before (N, Indic);
8762 Set_Parent (Indic, Parent (N));
8766 Set_Underlying_Full_View (Typ, Full_View (Subt));
8767 end Build_Underlying_Full_View;
8769 -------------------------------
8770 -- Check_Abstract_Overriding --
8771 -------------------------------
8773 procedure Check_Abstract_Overriding (T : Entity_Id) is
8774 Alias_Subp : Entity_Id;
8780 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8781 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8782 -- which has pragma Implemented already set. Check whether Subp's entity
8783 -- kind conforms to the implementation kind of the overridden routine.
8785 procedure Check_Pragma_Implemented
8787 Iface_Subp : Entity_Id);
8788 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8789 -- Iface_Subp and both entities have pragma Implemented already set on
8790 -- them. Check whether the two implementation kinds are conforming.
8792 procedure Inherit_Pragma_Implemented
8794 Iface_Subp : Entity_Id);
8795 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8796 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8797 -- Propagate the implementation kind of Iface_Subp to Subp.
8799 ------------------------------
8800 -- Check_Pragma_Implemented --
8801 ------------------------------
8803 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8804 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8805 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8806 Contr_Typ : Entity_Id;
8809 -- Subp must have an alias since it is a hidden entity used to link
8810 -- an interface subprogram to its overriding counterpart.
8812 pragma Assert (Present (Alias (Subp)));
8814 -- Extract the type of the controlling formal
8816 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8818 if Is_Concurrent_Record_Type (Contr_Typ) then
8819 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8822 -- An interface subprogram whose implementation kind is By_Entry must
8823 -- be implemented by an entry.
8825 if Impl_Kind = Name_By_Entry
8826 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8828 Error_Msg_Node_2 := Iface_Alias;
8830 ("type & must implement abstract subprogram & with an entry",
8831 Alias (Subp), Contr_Typ);
8833 elsif Impl_Kind = Name_By_Protected_Procedure then
8835 -- An interface subprogram whose implementation kind is By_
8836 -- Protected_Procedure cannot be implemented by a primitive
8837 -- procedure of a task type.
8839 if Ekind (Contr_Typ) /= E_Protected_Type then
8840 Error_Msg_Node_2 := Contr_Typ;
8842 ("interface subprogram & cannot be implemented by a " &
8843 "primitive procedure of task type &", Alias (Subp),
8846 -- An interface subprogram whose implementation kind is By_
8847 -- Protected_Procedure must be implemented by a procedure.
8849 elsif Is_Primitive_Wrapper (Alias (Subp))
8850 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8852 Error_Msg_Node_2 := Iface_Alias;
8854 ("type & must implement abstract subprogram & with a " &
8855 "procedure", Alias (Subp), Contr_Typ);
8858 end Check_Pragma_Implemented;
8860 ------------------------------
8861 -- Check_Pragma_Implemented --
8862 ------------------------------
8864 procedure Check_Pragma_Implemented
8866 Iface_Subp : Entity_Id)
8868 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8869 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8872 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8873 -- and overriding subprogram are different. In general this is an
8874 -- error except when the implementation kind of the overridden
8875 -- subprograms is By_Any.
8877 if Iface_Kind /= Subp_Kind
8878 and then Iface_Kind /= Name_By_Any
8880 if Iface_Kind = Name_By_Entry then
8882 ("incompatible implementation kind, overridden subprogram " &
8883 "is marked By_Entry", Subp);
8886 ("incompatible implementation kind, overridden subprogram " &
8887 "is marked By_Protected_Procedure", Subp);
8890 end Check_Pragma_Implemented;
8892 --------------------------------
8893 -- Inherit_Pragma_Implemented --
8894 --------------------------------
8896 procedure Inherit_Pragma_Implemented
8898 Iface_Subp : Entity_Id)
8900 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8901 Loc : constant Source_Ptr := Sloc (Subp);
8902 Impl_Prag : Node_Id;
8905 -- Since the implementation kind is stored as a representation item
8906 -- rather than a flag, create a pragma node.
8910 Chars => Name_Implemented,
8911 Pragma_Argument_Associations => New_List (
8912 Make_Pragma_Argument_Association (Loc,
8914 New_Reference_To (Subp, Loc)),
8916 Make_Pragma_Argument_Association (Loc,
8917 Expression => Make_Identifier (Loc, Iface_Kind))));
8919 -- The pragma doesn't need to be analyzed because it is internally
8920 -- build. It is safe to directly register it as a rep item since we
8921 -- are only interested in the characters of the implementation kind.
8923 Record_Rep_Item (Subp, Impl_Prag);
8924 end Inherit_Pragma_Implemented;
8926 -- Start of processing for Check_Abstract_Overriding
8929 Op_List := Primitive_Operations (T);
8931 -- Loop to check primitive operations
8933 Elmt := First_Elmt (Op_List);
8934 while Present (Elmt) loop
8935 Subp := Node (Elmt);
8936 Alias_Subp := Alias (Subp);
8938 -- Inherited subprograms are identified by the fact that they do not
8939 -- come from source, and the associated source location is the
8940 -- location of the first subtype of the derived type.
8942 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8943 -- subprograms that "require overriding".
8945 -- Special exception, do not complain about failure to override the
8946 -- stream routines _Input and _Output, as well as the primitive
8947 -- operations used in dispatching selects since we always provide
8948 -- automatic overridings for these subprograms.
8950 -- Also ignore this rule for convention CIL since .NET libraries
8951 -- do bizarre things with interfaces???
8953 -- The partial view of T may have been a private extension, for
8954 -- which inherited functions dispatching on result are abstract.
8955 -- If the full view is a null extension, there is no need for
8956 -- overriding in Ada2005, but wrappers need to be built for them
8957 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
8959 if Is_Null_Extension (T)
8960 and then Has_Controlling_Result (Subp)
8961 and then Ada_Version >= Ada_2005
8962 and then Present (Alias_Subp)
8963 and then not Comes_From_Source (Subp)
8964 and then not Is_Abstract_Subprogram (Alias_Subp)
8965 and then not Is_Access_Type (Etype (Subp))
8969 -- Ada 2005 (AI-251): Internal entities of interfaces need no
8970 -- processing because this check is done with the aliased
8973 elsif Present (Interface_Alias (Subp)) then
8976 elsif (Is_Abstract_Subprogram (Subp)
8977 or else Requires_Overriding (Subp)
8979 (Has_Controlling_Result (Subp)
8980 and then Present (Alias_Subp)
8981 and then not Comes_From_Source (Subp)
8982 and then Sloc (Subp) = Sloc (First_Subtype (T))))
8983 and then not Is_TSS (Subp, TSS_Stream_Input)
8984 and then not Is_TSS (Subp, TSS_Stream_Output)
8985 and then not Is_Abstract_Type (T)
8986 and then Convention (T) /= Convention_CIL
8987 and then not Is_Predefined_Interface_Primitive (Subp)
8989 -- Ada 2005 (AI-251): Do not consider hidden entities associated
8990 -- with abstract interface types because the check will be done
8991 -- with the aliased entity (otherwise we generate a duplicated
8994 and then not Present (Interface_Alias (Subp))
8996 if Present (Alias_Subp) then
8998 -- Only perform the check for a derived subprogram when the
8999 -- type has an explicit record extension. This avoids incorrect
9000 -- flagging of abstract subprograms for the case of a type
9001 -- without an extension that is derived from a formal type
9002 -- with a tagged actual (can occur within a private part).
9004 -- Ada 2005 (AI-391): In the case of an inherited function with
9005 -- a controlling result of the type, the rule does not apply if
9006 -- the type is a null extension (unless the parent function
9007 -- itself is abstract, in which case the function must still be
9008 -- be overridden). The expander will generate an overriding
9009 -- wrapper function calling the parent subprogram (see
9010 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9012 Type_Def := Type_Definition (Parent (T));
9014 if Nkind (Type_Def) = N_Derived_Type_Definition
9015 and then Present (Record_Extension_Part (Type_Def))
9017 (Ada_Version < Ada_2005
9018 or else not Is_Null_Extension (T)
9019 or else Ekind (Subp) = E_Procedure
9020 or else not Has_Controlling_Result (Subp)
9021 or else Is_Abstract_Subprogram (Alias_Subp)
9022 or else Requires_Overriding (Subp)
9023 or else Is_Access_Type (Etype (Subp)))
9025 -- Avoid reporting error in case of abstract predefined
9026 -- primitive inherited from interface type because the
9027 -- body of internally generated predefined primitives
9028 -- of tagged types are generated later by Freeze_Type
9030 if Is_Interface (Root_Type (T))
9031 and then Is_Abstract_Subprogram (Subp)
9032 and then Is_Predefined_Dispatching_Operation (Subp)
9033 and then not Comes_From_Source (Ultimate_Alias (Subp))
9039 ("type must be declared abstract or & overridden",
9042 -- Traverse the whole chain of aliased subprograms to
9043 -- complete the error notification. This is especially
9044 -- useful for traceability of the chain of entities when
9045 -- the subprogram corresponds with an interface
9046 -- subprogram (which may be defined in another package).
9048 if Present (Alias_Subp) then
9054 while Present (Alias (E)) loop
9055 Error_Msg_Sloc := Sloc (E);
9057 ("\& has been inherited #", T, Subp);
9061 Error_Msg_Sloc := Sloc (E);
9063 ("\& has been inherited from subprogram #",
9069 -- Ada 2005 (AI-345): Protected or task type implementing
9070 -- abstract interfaces.
9072 elsif Is_Concurrent_Record_Type (T)
9073 and then Present (Interfaces (T))
9075 -- The controlling formal of Subp must be of mode "out",
9076 -- "in out" or an access-to-variable to be overridden.
9078 -- Error message below needs rewording (remember comma
9079 -- in -gnatj mode) ???
9081 if Ekind (First_Formal (Subp)) = E_In_Parameter
9082 and then Ekind (Subp) /= E_Function
9084 if not Is_Predefined_Dispatching_Operation (Subp) then
9086 ("first formal of & must be of mode `OUT`, " &
9087 "`IN OUT` or access-to-variable", T, Subp);
9089 ("\to be overridden by protected procedure or " &
9090 "entry (RM 9.4(11.9/2))", T);
9093 -- Some other kind of overriding failure
9097 ("interface subprogram & must be overridden",
9100 -- Examine primitive operations of synchronized type,
9101 -- to find homonyms that have the wrong profile.
9108 First_Entity (Corresponding_Concurrent_Type (T));
9109 while Present (Prim) loop
9110 if Chars (Prim) = Chars (Subp) then
9112 ("profile is not type conformant with "
9113 & "prefixed view profile of "
9114 & "inherited operation&", Prim, Subp);
9124 Error_Msg_Node_2 := T;
9126 ("abstract subprogram& not allowed for type&", Subp);
9128 -- Also post unconditional warning on the type (unconditional
9129 -- so that if there are more than one of these cases, we get
9130 -- them all, and not just the first one).
9132 Error_Msg_Node_2 := Subp;
9133 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9137 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9140 -- Subp is an expander-generated procedure which maps an interface
9141 -- alias to a protected wrapper. The interface alias is flagged by
9142 -- pragma Implemented. Ensure that Subp is a procedure when the
9143 -- implementation kind is By_Protected_Procedure or an entry when
9146 if Ada_Version >= Ada_2012
9147 and then Is_Hidden (Subp)
9148 and then Present (Interface_Alias (Subp))
9149 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9151 Check_Pragma_Implemented (Subp);
9154 -- Subp is an interface primitive which overrides another interface
9155 -- primitive marked with pragma Implemented.
9157 if Ada_Version >= Ada_2012
9158 and then Present (Overridden_Operation (Subp))
9159 and then Has_Rep_Pragma
9160 (Overridden_Operation (Subp), Name_Implemented)
9162 -- If the overriding routine is also marked by Implemented, check
9163 -- that the two implementation kinds are conforming.
9165 if Has_Rep_Pragma (Subp, Name_Implemented) then
9166 Check_Pragma_Implemented
9168 Iface_Subp => Overridden_Operation (Subp));
9170 -- Otherwise the overriding routine inherits the implementation
9171 -- kind from the overridden subprogram.
9174 Inherit_Pragma_Implemented
9176 Iface_Subp => Overridden_Operation (Subp));
9182 end Check_Abstract_Overriding;
9184 ------------------------------------------------
9185 -- Check_Access_Discriminant_Requires_Limited --
9186 ------------------------------------------------
9188 procedure Check_Access_Discriminant_Requires_Limited
9193 -- A discriminant_specification for an access discriminant shall appear
9194 -- only in the declaration for a task or protected type, or for a type
9195 -- with the reserved word 'limited' in its definition or in one of its
9196 -- ancestors (RM 3.7(10)).
9198 -- AI-0063: The proper condition is that type must be immutably limited,
9199 -- or else be a partial view.
9201 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9202 if Is_Immutably_Limited_Type (Current_Scope)
9204 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9205 and then Limited_Present (Parent (Current_Scope)))
9211 ("access discriminants allowed only for limited types", Loc);
9214 end Check_Access_Discriminant_Requires_Limited;
9216 -----------------------------------
9217 -- Check_Aliased_Component_Types --
9218 -----------------------------------
9220 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9224 -- ??? Also need to check components of record extensions, but not
9225 -- components of protected types (which are always limited).
9227 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9228 -- types to be unconstrained. This is safe because it is illegal to
9229 -- create access subtypes to such types with explicit discriminant
9232 if not Is_Limited_Type (T) then
9233 if Ekind (T) = E_Record_Type then
9234 C := First_Component (T);
9235 while Present (C) loop
9237 and then Has_Discriminants (Etype (C))
9238 and then not Is_Constrained (Etype (C))
9239 and then not In_Instance_Body
9240 and then Ada_Version < Ada_2005
9243 ("aliased component must be constrained (RM 3.6(11))",
9250 elsif Ekind (T) = E_Array_Type then
9251 if Has_Aliased_Components (T)
9252 and then Has_Discriminants (Component_Type (T))
9253 and then not Is_Constrained (Component_Type (T))
9254 and then not In_Instance_Body
9255 and then Ada_Version < Ada_2005
9258 ("aliased component type must be constrained (RM 3.6(11))",
9263 end Check_Aliased_Component_Types;
9265 ----------------------
9266 -- Check_Completion --
9267 ----------------------
9269 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9272 procedure Post_Error;
9273 -- Post error message for lack of completion for entity E
9279 procedure Post_Error is
9281 procedure Missing_Body;
9282 -- Output missing body message
9288 procedure Missing_Body is
9290 -- Spec is in same unit, so we can post on spec
9292 if In_Same_Source_Unit (Body_Id, E) then
9293 Error_Msg_N ("missing body for &", E);
9295 -- Spec is in a separate unit, so we have to post on the body
9298 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9302 -- Start of processing for Post_Error
9305 if not Comes_From_Source (E) then
9307 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9308 -- It may be an anonymous protected type created for a
9309 -- single variable. Post error on variable, if present.
9315 Var := First_Entity (Current_Scope);
9316 while Present (Var) loop
9317 exit when Etype (Var) = E
9318 and then Comes_From_Source (Var);
9323 if Present (Var) then
9330 -- If a generated entity has no completion, then either previous
9331 -- semantic errors have disabled the expansion phase, or else we had
9332 -- missing subunits, or else we are compiling without expansion,
9333 -- or else something is very wrong.
9335 if not Comes_From_Source (E) then
9337 (Serious_Errors_Detected > 0
9338 or else Configurable_Run_Time_Violations > 0
9339 or else Subunits_Missing
9340 or else not Expander_Active);
9343 -- Here for source entity
9346 -- Here if no body to post the error message, so we post the error
9347 -- on the declaration that has no completion. This is not really
9348 -- the right place to post it, think about this later ???
9350 if No (Body_Id) then
9353 ("missing full declaration for }", Parent (E), E);
9355 Error_Msg_NE ("missing body for &", Parent (E), E);
9358 -- Package body has no completion for a declaration that appears
9359 -- in the corresponding spec. Post error on the body, with a
9360 -- reference to the non-completed declaration.
9363 Error_Msg_Sloc := Sloc (E);
9366 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9368 elsif Is_Overloadable (E)
9369 and then Current_Entity_In_Scope (E) /= E
9371 -- It may be that the completion is mistyped and appears as
9372 -- a distinct overloading of the entity.
9375 Candidate : constant Entity_Id :=
9376 Current_Entity_In_Scope (E);
9377 Decl : constant Node_Id :=
9378 Unit_Declaration_Node (Candidate);
9381 if Is_Overloadable (Candidate)
9382 and then Ekind (Candidate) = Ekind (E)
9383 and then Nkind (Decl) = N_Subprogram_Body
9384 and then Acts_As_Spec (Decl)
9386 Check_Type_Conformant (Candidate, E);
9400 -- Start of processing for Check_Completion
9403 E := First_Entity (Current_Scope);
9404 while Present (E) loop
9405 if Is_Intrinsic_Subprogram (E) then
9408 -- The following situation requires special handling: a child unit
9409 -- that appears in the context clause of the body of its parent:
9411 -- procedure Parent.Child (...);
9413 -- with Parent.Child;
9414 -- package body Parent is
9416 -- Here Parent.Child appears as a local entity, but should not be
9417 -- flagged as requiring completion, because it is a compilation
9420 -- Ignore missing completion for a subprogram that does not come from
9421 -- source (including the _Call primitive operation of RAS types,
9422 -- which has to have the flag Comes_From_Source for other purposes):
9423 -- we assume that the expander will provide the missing completion.
9424 -- In case of previous errors, other expansion actions that provide
9425 -- bodies for null procedures with not be invoked, so inhibit message
9427 -- Note that E_Operator is not in the list that follows, because
9428 -- this kind is reserved for predefined operators, that are
9429 -- intrinsic and do not need completion.
9431 elsif Ekind (E) = E_Function
9432 or else Ekind (E) = E_Procedure
9433 or else Ekind (E) = E_Generic_Function
9434 or else Ekind (E) = E_Generic_Procedure
9436 if Has_Completion (E) then
9439 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9442 elsif Is_Subprogram (E)
9443 and then (not Comes_From_Source (E)
9444 or else Chars (E) = Name_uCall)
9449 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9453 elsif Nkind (Parent (E)) = N_Procedure_Specification
9454 and then Null_Present (Parent (E))
9455 and then Serious_Errors_Detected > 0
9463 elsif Is_Entry (E) then
9464 if not Has_Completion (E) and then
9465 (Ekind (Scope (E)) = E_Protected_Object
9466 or else Ekind (Scope (E)) = E_Protected_Type)
9471 elsif Is_Package_Or_Generic_Package (E) then
9472 if Unit_Requires_Body (E) then
9473 if not Has_Completion (E)
9474 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9480 elsif not Is_Child_Unit (E) then
9481 May_Need_Implicit_Body (E);
9484 elsif Ekind (E) = E_Incomplete_Type
9485 and then No (Underlying_Type (E))
9489 elsif (Ekind (E) = E_Task_Type or else
9490 Ekind (E) = E_Protected_Type)
9491 and then not Has_Completion (E)
9495 -- A single task declared in the current scope is a constant, verify
9496 -- that the body of its anonymous type is in the same scope. If the
9497 -- task is defined elsewhere, this may be a renaming declaration for
9498 -- which no completion is needed.
9500 elsif Ekind (E) = E_Constant
9501 and then Ekind (Etype (E)) = E_Task_Type
9502 and then not Has_Completion (Etype (E))
9503 and then Scope (Etype (E)) = Current_Scope
9507 elsif Ekind (E) = E_Protected_Object
9508 and then not Has_Completion (Etype (E))
9512 elsif Ekind (E) = E_Record_Type then
9513 if Is_Tagged_Type (E) then
9514 Check_Abstract_Overriding (E);
9515 Check_Conventions (E);
9518 Check_Aliased_Component_Types (E);
9520 elsif Ekind (E) = E_Array_Type then
9521 Check_Aliased_Component_Types (E);
9527 end Check_Completion;
9529 ----------------------------
9530 -- Check_Delta_Expression --
9531 ----------------------------
9533 procedure Check_Delta_Expression (E : Node_Id) is
9535 if not (Is_Real_Type (Etype (E))) then
9536 Wrong_Type (E, Any_Real);
9538 elsif not Is_OK_Static_Expression (E) then
9539 Flag_Non_Static_Expr
9540 ("non-static expression used for delta value!", E);
9542 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9543 Error_Msg_N ("delta expression must be positive", E);
9549 -- If any of above errors occurred, then replace the incorrect
9550 -- expression by the real 0.1, which should prevent further errors.
9553 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9554 Analyze_And_Resolve (E, Standard_Float);
9555 end Check_Delta_Expression;
9557 -----------------------------
9558 -- Check_Digits_Expression --
9559 -----------------------------
9561 procedure Check_Digits_Expression (E : Node_Id) is
9563 if not (Is_Integer_Type (Etype (E))) then
9564 Wrong_Type (E, Any_Integer);
9566 elsif not Is_OK_Static_Expression (E) then
9567 Flag_Non_Static_Expr
9568 ("non-static expression used for digits value!", E);
9570 elsif Expr_Value (E) <= 0 then
9571 Error_Msg_N ("digits value must be greater than zero", E);
9577 -- If any of above errors occurred, then replace the incorrect
9578 -- expression by the integer 1, which should prevent further errors.
9580 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9581 Analyze_And_Resolve (E, Standard_Integer);
9583 end Check_Digits_Expression;
9585 --------------------------
9586 -- Check_Initialization --
9587 --------------------------
9589 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9591 if Is_Limited_Type (T)
9592 and then not In_Instance
9593 and then not In_Inlined_Body
9595 if not OK_For_Limited_Init (T, Exp) then
9597 -- In GNAT mode, this is just a warning, to allow it to be evilly
9598 -- turned off. Otherwise it is a real error.
9602 ("?cannot initialize entities of limited type!", Exp);
9604 elsif Ada_Version < Ada_2005 then
9606 ("cannot initialize entities of limited type", Exp);
9607 Explain_Limited_Type (T, Exp);
9610 -- Specialize error message according to kind of illegal
9611 -- initial expression.
9613 if Nkind (Exp) = N_Type_Conversion
9614 and then Nkind (Expression (Exp)) = N_Function_Call
9617 ("illegal context for call"
9618 & " to function with limited result", Exp);
9622 ("initialization of limited object requires aggregate "
9623 & "or function call", Exp);
9628 end Check_Initialization;
9630 ----------------------
9631 -- Check_Interfaces --
9632 ----------------------
9634 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9635 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9638 Iface_Def : Node_Id;
9639 Iface_Typ : Entity_Id;
9640 Parent_Node : Node_Id;
9642 Is_Task : Boolean := False;
9643 -- Set True if parent type or any progenitor is a task interface
9645 Is_Protected : Boolean := False;
9646 -- Set True if parent type or any progenitor is a protected interface
9648 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9649 -- Check that a progenitor is compatible with declaration.
9650 -- Error is posted on Error_Node.
9656 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9657 Iface_Id : constant Entity_Id :=
9658 Defining_Identifier (Parent (Iface_Def));
9662 if Nkind (N) = N_Private_Extension_Declaration then
9665 Type_Def := Type_Definition (N);
9668 if Is_Task_Interface (Iface_Id) then
9671 elsif Is_Protected_Interface (Iface_Id) then
9672 Is_Protected := True;
9675 if Is_Synchronized_Interface (Iface_Id) then
9677 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9678 -- extension derived from a synchronized interface must explicitly
9679 -- be declared synchronized, because the full view will be a
9680 -- synchronized type.
9682 if Nkind (N) = N_Private_Extension_Declaration then
9683 if not Synchronized_Present (N) then
9685 ("private extension of& must be explicitly synchronized",
9689 -- However, by 3.9.4(16/2), a full type that is a record extension
9690 -- is never allowed to derive from a synchronized interface (note
9691 -- that interfaces must be excluded from this check, because those
9692 -- are represented by derived type definitions in some cases).
9694 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9695 and then not Interface_Present (Type_Definition (N))
9697 Error_Msg_N ("record extension cannot derive from synchronized"
9698 & " interface", Error_Node);
9702 -- Check that the characteristics of the progenitor are compatible
9703 -- with the explicit qualifier in the declaration.
9704 -- The check only applies to qualifiers that come from source.
9705 -- Limited_Present also appears in the declaration of corresponding
9706 -- records, and the check does not apply to them.
9708 if Limited_Present (Type_Def)
9710 Is_Concurrent_Record_Type (Defining_Identifier (N))
9712 if Is_Limited_Interface (Parent_Type)
9713 and then not Is_Limited_Interface (Iface_Id)
9716 ("progenitor& must be limited interface",
9717 Error_Node, Iface_Id);
9720 (Task_Present (Iface_Def)
9721 or else Protected_Present (Iface_Def)
9722 or else Synchronized_Present (Iface_Def))
9723 and then Nkind (N) /= N_Private_Extension_Declaration
9724 and then not Error_Posted (N)
9727 ("progenitor& must be limited interface",
9728 Error_Node, Iface_Id);
9731 -- Protected interfaces can only inherit from limited, synchronized
9732 -- or protected interfaces.
9734 elsif Nkind (N) = N_Full_Type_Declaration
9735 and then Protected_Present (Type_Def)
9737 if Limited_Present (Iface_Def)
9738 or else Synchronized_Present (Iface_Def)
9739 or else Protected_Present (Iface_Def)
9743 elsif Task_Present (Iface_Def) then
9744 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9745 & " from task interface", Error_Node);
9748 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9749 & " from non-limited interface", Error_Node);
9752 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9753 -- limited and synchronized.
9755 elsif Synchronized_Present (Type_Def) then
9756 if Limited_Present (Iface_Def)
9757 or else Synchronized_Present (Iface_Def)
9761 elsif Protected_Present (Iface_Def)
9762 and then Nkind (N) /= N_Private_Extension_Declaration
9764 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9765 & " from protected interface", Error_Node);
9767 elsif Task_Present (Iface_Def)
9768 and then Nkind (N) /= N_Private_Extension_Declaration
9770 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9771 & " from task interface", Error_Node);
9773 elsif not Is_Limited_Interface (Iface_Id) then
9774 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9775 & " from non-limited interface", Error_Node);
9778 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9779 -- synchronized or task interfaces.
9781 elsif Nkind (N) = N_Full_Type_Declaration
9782 and then Task_Present (Type_Def)
9784 if Limited_Present (Iface_Def)
9785 or else Synchronized_Present (Iface_Def)
9786 or else Task_Present (Iface_Def)
9790 elsif Protected_Present (Iface_Def) then
9791 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9792 & " protected interface", Error_Node);
9795 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9796 & " non-limited interface", Error_Node);
9801 -- Start of processing for Check_Interfaces
9804 if Is_Interface (Parent_Type) then
9805 if Is_Task_Interface (Parent_Type) then
9808 elsif Is_Protected_Interface (Parent_Type) then
9809 Is_Protected := True;
9813 if Nkind (N) = N_Private_Extension_Declaration then
9815 -- Check that progenitors are compatible with declaration
9817 Iface := First (Interface_List (Def));
9818 while Present (Iface) loop
9819 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9821 Parent_Node := Parent (Base_Type (Iface_Typ));
9822 Iface_Def := Type_Definition (Parent_Node);
9824 if not Is_Interface (Iface_Typ) then
9825 Diagnose_Interface (Iface, Iface_Typ);
9828 Check_Ifaces (Iface_Def, Iface);
9834 if Is_Task and Is_Protected then
9836 ("type cannot derive from task and protected interface", N);
9842 -- Full type declaration of derived type.
9843 -- Check compatibility with parent if it is interface type
9845 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9846 and then Is_Interface (Parent_Type)
9848 Parent_Node := Parent (Parent_Type);
9850 -- More detailed checks for interface varieties
9853 (Iface_Def => Type_Definition (Parent_Node),
9854 Error_Node => Subtype_Indication (Type_Definition (N)));
9857 Iface := First (Interface_List (Def));
9858 while Present (Iface) loop
9859 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9861 Parent_Node := Parent (Base_Type (Iface_Typ));
9862 Iface_Def := Type_Definition (Parent_Node);
9864 if not Is_Interface (Iface_Typ) then
9865 Diagnose_Interface (Iface, Iface_Typ);
9868 -- "The declaration of a specific descendant of an interface
9869 -- type freezes the interface type" RM 13.14
9871 Freeze_Before (N, Iface_Typ);
9872 Check_Ifaces (Iface_Def, Error_Node => Iface);
9878 if Is_Task and Is_Protected then
9880 ("type cannot derive from task and protected interface", N);
9882 end Check_Interfaces;
9884 ------------------------------------
9885 -- Check_Or_Process_Discriminants --
9886 ------------------------------------
9888 -- If an incomplete or private type declaration was already given for the
9889 -- type, the discriminants may have already been processed if they were
9890 -- present on the incomplete declaration. In this case a full conformance
9891 -- check has been performed in Find_Type_Name, and we then recheck here
9892 -- some properties that can't be checked on the partial view alone.
9893 -- Otherwise we call Process_Discriminants.
9895 procedure Check_Or_Process_Discriminants
9898 Prev : Entity_Id := Empty)
9901 if Has_Discriminants (T) then
9903 -- Discriminants are already set on T if they were already present
9904 -- on the partial view. Make them visible to component declarations.
9908 -- Discriminant on T (full view) referencing expr on partial view
9911 -- Entity of corresponding discriminant on partial view
9914 -- Discriminant specification for full view, expression is the
9915 -- syntactic copy on full view (which has been checked for
9916 -- conformance with partial view), only used here to post error
9920 D := First_Discriminant (T);
9921 New_D := First (Discriminant_Specifications (N));
9922 while Present (D) loop
9923 Prev_D := Current_Entity (D);
9924 Set_Current_Entity (D);
9925 Set_Is_Immediately_Visible (D);
9926 Set_Homonym (D, Prev_D);
9928 -- Handle the case where there is an untagged partial view and
9929 -- the full view is tagged: must disallow discriminants with
9930 -- defaults, unless compiling for Ada 2012, which allows a
9931 -- limited tagged type to have defaulted discriminants (see
9932 -- AI05-0214). However, suppress the error here if it was
9933 -- already reported on the default expression of the partial
9936 if Is_Tagged_Type (T)
9937 and then Present (Expression (Parent (D)))
9938 and then (not Is_Limited_Type (Current_Scope)
9939 or else Ada_Version < Ada_2012)
9940 and then not Error_Posted (Expression (Parent (D)))
9942 if Ada_Version >= Ada_2012 then
9944 ("discriminants of nonlimited tagged type cannot have"
9946 Expression (New_D));
9949 ("discriminants of tagged type cannot have defaults",
9950 Expression (New_D));
9954 -- Ada 2005 (AI-230): Access discriminant allowed in
9955 -- non-limited record types.
9957 if Ada_Version < Ada_2005 then
9959 -- This restriction gets applied to the full type here. It
9960 -- has already been applied earlier to the partial view.
9962 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
9965 Next_Discriminant (D);
9970 elsif Present (Discriminant_Specifications (N)) then
9971 Process_Discriminants (N, Prev);
9973 end Check_Or_Process_Discriminants;
9975 ----------------------
9976 -- Check_Real_Bound --
9977 ----------------------
9979 procedure Check_Real_Bound (Bound : Node_Id) is
9981 if not Is_Real_Type (Etype (Bound)) then
9983 ("bound in real type definition must be of real type", Bound);
9985 elsif not Is_OK_Static_Expression (Bound) then
9986 Flag_Non_Static_Expr
9987 ("non-static expression used for real type bound!", Bound);
9994 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
9996 Resolve (Bound, Standard_Float);
9997 end Check_Real_Bound;
9999 ------------------------------
10000 -- Complete_Private_Subtype --
10001 ------------------------------
10003 procedure Complete_Private_Subtype
10006 Full_Base : Entity_Id;
10007 Related_Nod : Node_Id)
10009 Save_Next_Entity : Entity_Id;
10010 Save_Homonym : Entity_Id;
10013 -- Set semantic attributes for (implicit) private subtype completion.
10014 -- If the full type has no discriminants, then it is a copy of the full
10015 -- view of the base. Otherwise, it is a subtype of the base with a
10016 -- possible discriminant constraint. Save and restore the original
10017 -- Next_Entity field of full to ensure that the calls to Copy_Node
10018 -- do not corrupt the entity chain.
10020 -- Note that the type of the full view is the same entity as the type of
10021 -- the partial view. In this fashion, the subtype has access to the
10022 -- correct view of the parent.
10024 Save_Next_Entity := Next_Entity (Full);
10025 Save_Homonym := Homonym (Priv);
10027 case Ekind (Full_Base) is
10028 when E_Record_Type |
10034 Copy_Node (Priv, Full);
10036 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10037 Set_First_Entity (Full, First_Entity (Full_Base));
10038 Set_Last_Entity (Full, Last_Entity (Full_Base));
10041 Copy_Node (Full_Base, Full);
10042 Set_Chars (Full, Chars (Priv));
10043 Conditional_Delay (Full, Priv);
10044 Set_Sloc (Full, Sloc (Priv));
10047 Set_Next_Entity (Full, Save_Next_Entity);
10048 Set_Homonym (Full, Save_Homonym);
10049 Set_Associated_Node_For_Itype (Full, Related_Nod);
10051 -- Set common attributes for all subtypes: kind, convention, etc.
10053 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10054 Set_Convention (Full, Convention (Full_Base));
10056 -- The Etype of the full view is inconsistent. Gigi needs to see the
10057 -- structural full view, which is what the current scheme gives:
10058 -- the Etype of the full view is the etype of the full base. However,
10059 -- if the full base is a derived type, the full view then looks like
10060 -- a subtype of the parent, not a subtype of the full base. If instead
10063 -- Set_Etype (Full, Full_Base);
10065 -- then we get inconsistencies in the front-end (confusion between
10066 -- views). Several outstanding bugs are related to this ???
10068 Set_Is_First_Subtype (Full, False);
10069 Set_Scope (Full, Scope (Priv));
10070 Set_Size_Info (Full, Full_Base);
10071 Set_RM_Size (Full, RM_Size (Full_Base));
10072 Set_Is_Itype (Full);
10074 -- A subtype of a private-type-without-discriminants, whose full-view
10075 -- has discriminants with default expressions, is not constrained!
10077 if not Has_Discriminants (Priv) then
10078 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10080 if Has_Discriminants (Full_Base) then
10081 Set_Discriminant_Constraint
10082 (Full, Discriminant_Constraint (Full_Base));
10084 -- The partial view may have been indefinite, the full view
10087 Set_Has_Unknown_Discriminants
10088 (Full, Has_Unknown_Discriminants (Full_Base));
10092 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10093 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10095 -- Freeze the private subtype entity if its parent is delayed, and not
10096 -- already frozen. We skip this processing if the type is an anonymous
10097 -- subtype of a record component, or is the corresponding record of a
10098 -- protected type, since ???
10100 if not Is_Type (Scope (Full)) then
10101 Set_Has_Delayed_Freeze (Full,
10102 Has_Delayed_Freeze (Full_Base)
10103 and then (not Is_Frozen (Full_Base)));
10106 Set_Freeze_Node (Full, Empty);
10107 Set_Is_Frozen (Full, False);
10108 Set_Full_View (Priv, Full);
10110 if Has_Discriminants (Full) then
10111 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10112 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10114 if Has_Unknown_Discriminants (Full) then
10115 Set_Discriminant_Constraint (Full, No_Elist);
10119 if Ekind (Full_Base) = E_Record_Type
10120 and then Has_Discriminants (Full_Base)
10121 and then Has_Discriminants (Priv) -- might not, if errors
10122 and then not Has_Unknown_Discriminants (Priv)
10123 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10125 Create_Constrained_Components
10126 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10128 -- If the full base is itself derived from private, build a congruent
10129 -- subtype of its underlying type, for use by the back end. For a
10130 -- constrained record component, the declaration cannot be placed on
10131 -- the component list, but it must nevertheless be built an analyzed, to
10132 -- supply enough information for Gigi to compute the size of component.
10134 elsif Ekind (Full_Base) in Private_Kind
10135 and then Is_Derived_Type (Full_Base)
10136 and then Has_Discriminants (Full_Base)
10137 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10139 if not Is_Itype (Priv)
10141 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10143 Build_Underlying_Full_View
10144 (Parent (Priv), Full, Etype (Full_Base));
10146 elsif Nkind (Related_Nod) = N_Component_Declaration then
10147 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10150 elsif Is_Record_Type (Full_Base) then
10152 -- Show Full is simply a renaming of Full_Base
10154 Set_Cloned_Subtype (Full, Full_Base);
10157 -- It is unsafe to share to bounds of a scalar type, because the Itype
10158 -- is elaborated on demand, and if a bound is non-static then different
10159 -- orders of elaboration in different units will lead to different
10160 -- external symbols.
10162 if Is_Scalar_Type (Full_Base) then
10163 Set_Scalar_Range (Full,
10164 Make_Range (Sloc (Related_Nod),
10166 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10168 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10170 -- This completion inherits the bounds of the full parent, but if
10171 -- the parent is an unconstrained floating point type, so is the
10174 if Is_Floating_Point_Type (Full_Base) then
10175 Set_Includes_Infinities
10176 (Scalar_Range (Full), Has_Infinities (Full_Base));
10180 -- ??? It seems that a lot of fields are missing that should be copied
10181 -- from Full_Base to Full. Here are some that are introduced in a
10182 -- non-disruptive way but a cleanup is necessary.
10184 if Is_Tagged_Type (Full_Base) then
10185 Set_Is_Tagged_Type (Full);
10186 Set_Direct_Primitive_Operations (Full,
10187 Direct_Primitive_Operations (Full_Base));
10189 -- Inherit class_wide type of full_base in case the partial view was
10190 -- not tagged. Otherwise it has already been created when the private
10191 -- subtype was analyzed.
10193 if No (Class_Wide_Type (Full)) then
10194 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10197 -- If this is a subtype of a protected or task type, constrain its
10198 -- corresponding record, unless this is a subtype without constraints,
10199 -- i.e. a simple renaming as with an actual subtype in an instance.
10201 elsif Is_Concurrent_Type (Full_Base) then
10202 if Has_Discriminants (Full)
10203 and then Present (Corresponding_Record_Type (Full_Base))
10205 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10207 Set_Corresponding_Record_Type (Full,
10208 Constrain_Corresponding_Record
10209 (Full, Corresponding_Record_Type (Full_Base),
10210 Related_Nod, Full_Base));
10213 Set_Corresponding_Record_Type (Full,
10214 Corresponding_Record_Type (Full_Base));
10218 -- Link rep item chain, and also setting of Has_Predicates from private
10219 -- subtype to full subtype, since we will need these on the full subtype
10220 -- to create the predicate function. Note that the full subtype may
10221 -- already have rep items, inherited from the full view of the base
10222 -- type, so we must be sure not to overwrite these entries.
10226 Next_Item : Node_Id;
10229 Item := First_Rep_Item (Full);
10231 -- If no existing rep items on full type, we can just link directly
10232 -- to the list of items on the private type.
10235 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10237 -- Otherwise, search to the end of items currently linked to the full
10238 -- subtype and append the private items to the end. However, if Priv
10239 -- and Full already have the same list of rep items, then the append
10240 -- is not done, as that would create a circularity.
10242 elsif Item /= First_Rep_Item (Priv) then
10244 Next_Item := Next_Rep_Item (Item);
10245 exit when No (Next_Item);
10249 -- And link the private type items at the end of the chain
10251 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10255 -- Make sure Has_Predicates is set on full type if it is set on the
10256 -- private type. Note that it may already be set on the full type and
10257 -- if so, we don't want to unset it.
10259 if Has_Predicates (Priv) then
10260 Set_Has_Predicates (Full);
10262 end Complete_Private_Subtype;
10264 ----------------------------
10265 -- Constant_Redeclaration --
10266 ----------------------------
10268 procedure Constant_Redeclaration
10273 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10274 Obj_Def : constant Node_Id := Object_Definition (N);
10277 procedure Check_Possible_Deferred_Completion
10278 (Prev_Id : Entity_Id;
10279 Prev_Obj_Def : Node_Id;
10280 Curr_Obj_Def : Node_Id);
10281 -- Determine whether the two object definitions describe the partial
10282 -- and the full view of a constrained deferred constant. Generate
10283 -- a subtype for the full view and verify that it statically matches
10284 -- the subtype of the partial view.
10286 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10287 -- If deferred constant is an access type initialized with an allocator,
10288 -- check whether there is an illegal recursion in the definition,
10289 -- through a default value of some record subcomponent. This is normally
10290 -- detected when generating init procs, but requires this additional
10291 -- mechanism when expansion is disabled.
10293 ----------------------------------------
10294 -- Check_Possible_Deferred_Completion --
10295 ----------------------------------------
10297 procedure Check_Possible_Deferred_Completion
10298 (Prev_Id : Entity_Id;
10299 Prev_Obj_Def : Node_Id;
10300 Curr_Obj_Def : Node_Id)
10303 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10304 and then Present (Constraint (Prev_Obj_Def))
10305 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10306 and then Present (Constraint (Curr_Obj_Def))
10309 Loc : constant Source_Ptr := Sloc (N);
10310 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10311 Decl : constant Node_Id :=
10312 Make_Subtype_Declaration (Loc,
10313 Defining_Identifier => Def_Id,
10314 Subtype_Indication =>
10315 Relocate_Node (Curr_Obj_Def));
10318 Insert_Before_And_Analyze (N, Decl);
10319 Set_Etype (Id, Def_Id);
10321 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10322 Error_Msg_Sloc := Sloc (Prev_Id);
10323 Error_Msg_N ("subtype does not statically match deferred " &
10324 "declaration#", N);
10328 end Check_Possible_Deferred_Completion;
10330 ---------------------------------
10331 -- Check_Recursive_Declaration --
10332 ---------------------------------
10334 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10338 if Is_Record_Type (Typ) then
10339 Comp := First_Component (Typ);
10340 while Present (Comp) loop
10341 if Comes_From_Source (Comp) then
10342 if Present (Expression (Parent (Comp)))
10343 and then Is_Entity_Name (Expression (Parent (Comp)))
10344 and then Entity (Expression (Parent (Comp))) = Prev
10346 Error_Msg_Sloc := Sloc (Parent (Comp));
10348 ("illegal circularity with declaration for&#",
10352 elsif Is_Record_Type (Etype (Comp)) then
10353 Check_Recursive_Declaration (Etype (Comp));
10357 Next_Component (Comp);
10360 end Check_Recursive_Declaration;
10362 -- Start of processing for Constant_Redeclaration
10365 if Nkind (Parent (Prev)) = N_Object_Declaration then
10366 if Nkind (Object_Definition
10367 (Parent (Prev))) = N_Subtype_Indication
10369 -- Find type of new declaration. The constraints of the two
10370 -- views must match statically, but there is no point in
10371 -- creating an itype for the full view.
10373 if Nkind (Obj_Def) = N_Subtype_Indication then
10374 Find_Type (Subtype_Mark (Obj_Def));
10375 New_T := Entity (Subtype_Mark (Obj_Def));
10378 Find_Type (Obj_Def);
10379 New_T := Entity (Obj_Def);
10385 -- The full view may impose a constraint, even if the partial
10386 -- view does not, so construct the subtype.
10388 New_T := Find_Type_Of_Object (Obj_Def, N);
10393 -- Current declaration is illegal, diagnosed below in Enter_Name
10399 -- If previous full declaration or a renaming declaration exists, or if
10400 -- a homograph is present, let Enter_Name handle it, either with an
10401 -- error or with the removal of an overridden implicit subprogram.
10403 if Ekind (Prev) /= E_Constant
10404 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10405 or else Present (Expression (Parent (Prev)))
10406 or else Present (Full_View (Prev))
10410 -- Verify that types of both declarations match, or else that both types
10411 -- are anonymous access types whose designated subtypes statically match
10412 -- (as allowed in Ada 2005 by AI-385).
10414 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10416 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10417 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10418 or else Is_Access_Constant (Etype (New_T)) /=
10419 Is_Access_Constant (Etype (Prev))
10420 or else Can_Never_Be_Null (Etype (New_T)) /=
10421 Can_Never_Be_Null (Etype (Prev))
10422 or else Null_Exclusion_Present (Parent (Prev)) /=
10423 Null_Exclusion_Present (Parent (Id))
10424 or else not Subtypes_Statically_Match
10425 (Designated_Type (Etype (Prev)),
10426 Designated_Type (Etype (New_T))))
10428 Error_Msg_Sloc := Sloc (Prev);
10429 Error_Msg_N ("type does not match declaration#", N);
10430 Set_Full_View (Prev, Id);
10431 Set_Etype (Id, Any_Type);
10434 Null_Exclusion_Present (Parent (Prev))
10435 and then not Null_Exclusion_Present (N)
10437 Error_Msg_Sloc := Sloc (Prev);
10438 Error_Msg_N ("null-exclusion does not match declaration#", N);
10439 Set_Full_View (Prev, Id);
10440 Set_Etype (Id, Any_Type);
10442 -- If so, process the full constant declaration
10445 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10446 -- the deferred declaration is constrained, then the subtype defined
10447 -- by the subtype_indication in the full declaration shall match it
10450 Check_Possible_Deferred_Completion
10452 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10453 Curr_Obj_Def => Obj_Def);
10455 Set_Full_View (Prev, Id);
10456 Set_Is_Public (Id, Is_Public (Prev));
10457 Set_Is_Internal (Id);
10458 Append_Entity (Id, Current_Scope);
10460 -- Check ALIASED present if present before (RM 7.4(7))
10462 if Is_Aliased (Prev)
10463 and then not Aliased_Present (N)
10465 Error_Msg_Sloc := Sloc (Prev);
10466 Error_Msg_N ("ALIASED required (see declaration#)", N);
10469 -- Check that placement is in private part and that the incomplete
10470 -- declaration appeared in the visible part.
10472 if Ekind (Current_Scope) = E_Package
10473 and then not In_Private_Part (Current_Scope)
10475 Error_Msg_Sloc := Sloc (Prev);
10477 ("full constant for declaration#"
10478 & " must be in private part", N);
10480 elsif Ekind (Current_Scope) = E_Package
10482 List_Containing (Parent (Prev)) /=
10483 Visible_Declarations
10484 (Specification (Unit_Declaration_Node (Current_Scope)))
10487 ("deferred constant must be declared in visible part",
10491 if Is_Access_Type (T)
10492 and then Nkind (Expression (N)) = N_Allocator
10494 Check_Recursive_Declaration (Designated_Type (T));
10497 end Constant_Redeclaration;
10499 ----------------------
10500 -- Constrain_Access --
10501 ----------------------
10503 procedure Constrain_Access
10504 (Def_Id : in out Entity_Id;
10506 Related_Nod : Node_Id)
10508 T : constant Entity_Id := Entity (Subtype_Mark (S));
10509 Desig_Type : constant Entity_Id := Designated_Type (T);
10510 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10511 Constraint_OK : Boolean := True;
10513 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10514 -- Simple predicate to test for defaulted discriminants
10515 -- Shouldn't this be in sem_util???
10517 ---------------------------------
10518 -- Has_Defaulted_Discriminants --
10519 ---------------------------------
10521 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10523 return Has_Discriminants (Typ)
10524 and then Present (First_Discriminant (Typ))
10526 (Discriminant_Default_Value (First_Discriminant (Typ)));
10527 end Has_Defaulted_Discriminants;
10529 -- Start of processing for Constrain_Access
10532 if Is_Array_Type (Desig_Type) then
10533 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10535 elsif (Is_Record_Type (Desig_Type)
10536 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10537 and then not Is_Constrained (Desig_Type)
10539 -- ??? The following code is a temporary kludge to ignore a
10540 -- discriminant constraint on access type if it is constraining
10541 -- the current record. Avoid creating the implicit subtype of the
10542 -- record we are currently compiling since right now, we cannot
10543 -- handle these. For now, just return the access type itself.
10545 if Desig_Type = Current_Scope
10546 and then No (Def_Id)
10548 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10549 Def_Id := Entity (Subtype_Mark (S));
10551 -- This call added to ensure that the constraint is analyzed
10552 -- (needed for a B test). Note that we still return early from
10553 -- this procedure to avoid recursive processing. ???
10555 Constrain_Discriminated_Type
10556 (Desig_Subtype, S, Related_Nod, For_Access => True);
10560 if (Ekind (T) = E_General_Access_Type
10561 or else Ada_Version >= Ada_2005)
10562 and then Has_Private_Declaration (Desig_Type)
10563 and then In_Open_Scopes (Scope (Desig_Type))
10564 and then Has_Discriminants (Desig_Type)
10566 -- Enforce rule that the constraint is illegal if there is
10567 -- an unconstrained view of the designated type. This means
10568 -- that the partial view (either a private type declaration or
10569 -- a derivation from a private type) has no discriminants.
10570 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
10571 -- by ACATS B371001).
10573 -- Rule updated for Ada 2005: the private type is said to have
10574 -- a constrained partial view, given that objects of the type
10575 -- can be declared. Furthermore, the rule applies to all access
10576 -- types, unlike the rule concerning default discriminants.
10579 Pack : constant Node_Id :=
10580 Unit_Declaration_Node (Scope (Desig_Type));
10585 if Nkind (Pack) = N_Package_Declaration then
10586 Decls := Visible_Declarations (Specification (Pack));
10587 Decl := First (Decls);
10588 while Present (Decl) loop
10589 if (Nkind (Decl) = N_Private_Type_Declaration
10591 Chars (Defining_Identifier (Decl)) =
10592 Chars (Desig_Type))
10595 (Nkind (Decl) = N_Full_Type_Declaration
10597 Chars (Defining_Identifier (Decl)) =
10599 and then Is_Derived_Type (Desig_Type)
10601 Has_Private_Declaration (Etype (Desig_Type)))
10603 if No (Discriminant_Specifications (Decl)) then
10605 ("cannot constrain general access type if " &
10606 "designated type has constrained partial view",
10619 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10620 For_Access => True);
10622 elsif (Is_Task_Type (Desig_Type)
10623 or else Is_Protected_Type (Desig_Type))
10624 and then not Is_Constrained (Desig_Type)
10626 Constrain_Concurrent
10627 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10630 Error_Msg_N ("invalid constraint on access type", S);
10631 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10632 Constraint_OK := False;
10635 if No (Def_Id) then
10636 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10638 Set_Ekind (Def_Id, E_Access_Subtype);
10641 if Constraint_OK then
10642 Set_Etype (Def_Id, Base_Type (T));
10644 if Is_Private_Type (Desig_Type) then
10645 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10648 Set_Etype (Def_Id, Any_Type);
10651 Set_Size_Info (Def_Id, T);
10652 Set_Is_Constrained (Def_Id, Constraint_OK);
10653 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10654 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10655 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10657 Conditional_Delay (Def_Id, T);
10659 -- AI-363 : Subtypes of general access types whose designated types have
10660 -- default discriminants are disallowed. In instances, the rule has to
10661 -- be checked against the actual, of which T is the subtype. In a
10662 -- generic body, the rule is checked assuming that the actual type has
10663 -- defaulted discriminants.
10665 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10666 if Ekind (Base_Type (T)) = E_General_Access_Type
10667 and then Has_Defaulted_Discriminants (Desig_Type)
10669 if Ada_Version < Ada_2005 then
10671 ("access subtype of general access type would not " &
10672 "be allowed in Ada 2005?", S);
10675 ("access subtype of general access type not allowed", S);
10678 Error_Msg_N ("\discriminants have defaults", S);
10680 elsif Is_Access_Type (T)
10681 and then Is_Generic_Type (Desig_Type)
10682 and then Has_Discriminants (Desig_Type)
10683 and then In_Package_Body (Current_Scope)
10685 if Ada_Version < Ada_2005 then
10687 ("access subtype would not be allowed in generic body " &
10688 "in Ada 2005?", S);
10691 ("access subtype not allowed in generic body", S);
10695 ("\designated type is a discriminated formal", S);
10698 end Constrain_Access;
10700 ---------------------
10701 -- Constrain_Array --
10702 ---------------------
10704 procedure Constrain_Array
10705 (Def_Id : in out Entity_Id;
10707 Related_Nod : Node_Id;
10708 Related_Id : Entity_Id;
10709 Suffix : Character)
10711 C : constant Node_Id := Constraint (SI);
10712 Number_Of_Constraints : Nat := 0;
10715 Constraint_OK : Boolean := True;
10718 T := Entity (Subtype_Mark (SI));
10720 if Ekind (T) in Access_Kind then
10721 T := Designated_Type (T);
10724 -- If an index constraint follows a subtype mark in a subtype indication
10725 -- then the type or subtype denoted by the subtype mark must not already
10726 -- impose an index constraint. The subtype mark must denote either an
10727 -- unconstrained array type or an access type whose designated type
10728 -- is such an array type... (RM 3.6.1)
10730 if Is_Constrained (T) then
10731 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10732 Constraint_OK := False;
10735 S := First (Constraints (C));
10736 while Present (S) loop
10737 Number_Of_Constraints := Number_Of_Constraints + 1;
10741 -- In either case, the index constraint must provide a discrete
10742 -- range for each index of the array type and the type of each
10743 -- discrete range must be the same as that of the corresponding
10744 -- index. (RM 3.6.1)
10746 if Number_Of_Constraints /= Number_Dimensions (T) then
10747 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10748 Constraint_OK := False;
10751 S := First (Constraints (C));
10752 Index := First_Index (T);
10755 -- Apply constraints to each index type
10757 for J in 1 .. Number_Of_Constraints loop
10758 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10766 if No (Def_Id) then
10768 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10769 Set_Parent (Def_Id, Related_Nod);
10772 Set_Ekind (Def_Id, E_Array_Subtype);
10775 Set_Size_Info (Def_Id, (T));
10776 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10777 Set_Etype (Def_Id, Base_Type (T));
10779 if Constraint_OK then
10780 Set_First_Index (Def_Id, First (Constraints (C)));
10782 Set_First_Index (Def_Id, First_Index (T));
10785 Set_Is_Constrained (Def_Id, True);
10786 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10787 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10789 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10790 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10792 -- A subtype does not inherit the packed_array_type of is parent. We
10793 -- need to initialize the attribute because if Def_Id is previously
10794 -- analyzed through a limited_with clause, it will have the attributes
10795 -- of an incomplete type, one of which is an Elist that overlaps the
10796 -- Packed_Array_Type field.
10798 Set_Packed_Array_Type (Def_Id, Empty);
10800 -- Build a freeze node if parent still needs one. Also make sure that
10801 -- the Depends_On_Private status is set because the subtype will need
10802 -- reprocessing at the time the base type does, and also we must set a
10803 -- conditional delay.
10805 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10806 Conditional_Delay (Def_Id, T);
10807 end Constrain_Array;
10809 ------------------------------
10810 -- Constrain_Component_Type --
10811 ------------------------------
10813 function Constrain_Component_Type
10815 Constrained_Typ : Entity_Id;
10816 Related_Node : Node_Id;
10818 Constraints : Elist_Id) return Entity_Id
10820 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10821 Compon_Type : constant Entity_Id := Etype (Comp);
10823 function Build_Constrained_Array_Type
10824 (Old_Type : Entity_Id) return Entity_Id;
10825 -- If Old_Type is an array type, one of whose indexes is constrained
10826 -- by a discriminant, build an Itype whose constraint replaces the
10827 -- discriminant with its value in the constraint.
10829 function Build_Constrained_Discriminated_Type
10830 (Old_Type : Entity_Id) return Entity_Id;
10831 -- Ditto for record components
10833 function Build_Constrained_Access_Type
10834 (Old_Type : Entity_Id) return Entity_Id;
10835 -- Ditto for access types. Makes use of previous two functions, to
10836 -- constrain designated type.
10838 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10839 -- T is an array or discriminated type, C is a list of constraints
10840 -- that apply to T. This routine builds the constrained subtype.
10842 function Is_Discriminant (Expr : Node_Id) return Boolean;
10843 -- Returns True if Expr is a discriminant
10845 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10846 -- Find the value of discriminant Discrim in Constraint
10848 -----------------------------------
10849 -- Build_Constrained_Access_Type --
10850 -----------------------------------
10852 function Build_Constrained_Access_Type
10853 (Old_Type : Entity_Id) return Entity_Id
10855 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10857 Desig_Subtype : Entity_Id;
10861 -- if the original access type was not embedded in the enclosing
10862 -- type definition, there is no need to produce a new access
10863 -- subtype. In fact every access type with an explicit constraint
10864 -- generates an itype whose scope is the enclosing record.
10866 if not Is_Type (Scope (Old_Type)) then
10869 elsif Is_Array_Type (Desig_Type) then
10870 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10872 elsif Has_Discriminants (Desig_Type) then
10874 -- This may be an access type to an enclosing record type for
10875 -- which we are constructing the constrained components. Return
10876 -- the enclosing record subtype. This is not always correct,
10877 -- but avoids infinite recursion. ???
10879 Desig_Subtype := Any_Type;
10881 for J in reverse 0 .. Scope_Stack.Last loop
10882 Scop := Scope_Stack.Table (J).Entity;
10885 and then Base_Type (Scop) = Base_Type (Desig_Type)
10887 Desig_Subtype := Scop;
10890 exit when not Is_Type (Scop);
10893 if Desig_Subtype = Any_Type then
10895 Build_Constrained_Discriminated_Type (Desig_Type);
10902 if Desig_Subtype /= Desig_Type then
10904 -- The Related_Node better be here or else we won't be able
10905 -- to attach new itypes to a node in the tree.
10907 pragma Assert (Present (Related_Node));
10909 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10911 Set_Etype (Itype, Base_Type (Old_Type));
10912 Set_Size_Info (Itype, (Old_Type));
10913 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10914 Set_Depends_On_Private (Itype, Has_Private_Component
10916 Set_Is_Access_Constant (Itype, Is_Access_Constant
10919 -- The new itype needs freezing when it depends on a not frozen
10920 -- type and the enclosing subtype needs freezing.
10922 if Has_Delayed_Freeze (Constrained_Typ)
10923 and then not Is_Frozen (Constrained_Typ)
10925 Conditional_Delay (Itype, Base_Type (Old_Type));
10933 end Build_Constrained_Access_Type;
10935 ----------------------------------
10936 -- Build_Constrained_Array_Type --
10937 ----------------------------------
10939 function Build_Constrained_Array_Type
10940 (Old_Type : Entity_Id) return Entity_Id
10944 Old_Index : Node_Id;
10945 Range_Node : Node_Id;
10946 Constr_List : List_Id;
10948 Need_To_Create_Itype : Boolean := False;
10951 Old_Index := First_Index (Old_Type);
10952 while Present (Old_Index) loop
10953 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10955 if Is_Discriminant (Lo_Expr)
10956 or else Is_Discriminant (Hi_Expr)
10958 Need_To_Create_Itype := True;
10961 Next_Index (Old_Index);
10964 if Need_To_Create_Itype then
10965 Constr_List := New_List;
10967 Old_Index := First_Index (Old_Type);
10968 while Present (Old_Index) loop
10969 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10971 if Is_Discriminant (Lo_Expr) then
10972 Lo_Expr := Get_Discr_Value (Lo_Expr);
10975 if Is_Discriminant (Hi_Expr) then
10976 Hi_Expr := Get_Discr_Value (Hi_Expr);
10981 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
10983 Append (Range_Node, To => Constr_List);
10985 Next_Index (Old_Index);
10988 return Build_Subtype (Old_Type, Constr_List);
10993 end Build_Constrained_Array_Type;
10995 ------------------------------------------
10996 -- Build_Constrained_Discriminated_Type --
10997 ------------------------------------------
10999 function Build_Constrained_Discriminated_Type
11000 (Old_Type : Entity_Id) return Entity_Id
11003 Constr_List : List_Id;
11004 Old_Constraint : Elmt_Id;
11006 Need_To_Create_Itype : Boolean := False;
11009 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11010 while Present (Old_Constraint) loop
11011 Expr := Node (Old_Constraint);
11013 if Is_Discriminant (Expr) then
11014 Need_To_Create_Itype := True;
11017 Next_Elmt (Old_Constraint);
11020 if Need_To_Create_Itype then
11021 Constr_List := New_List;
11023 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11024 while Present (Old_Constraint) loop
11025 Expr := Node (Old_Constraint);
11027 if Is_Discriminant (Expr) then
11028 Expr := Get_Discr_Value (Expr);
11031 Append (New_Copy_Tree (Expr), To => Constr_List);
11033 Next_Elmt (Old_Constraint);
11036 return Build_Subtype (Old_Type, Constr_List);
11041 end Build_Constrained_Discriminated_Type;
11043 -------------------
11044 -- Build_Subtype --
11045 -------------------
11047 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11049 Subtyp_Decl : Node_Id;
11050 Def_Id : Entity_Id;
11051 Btyp : Entity_Id := Base_Type (T);
11054 -- The Related_Node better be here or else we won't be able to
11055 -- attach new itypes to a node in the tree.
11057 pragma Assert (Present (Related_Node));
11059 -- If the view of the component's type is incomplete or private
11060 -- with unknown discriminants, then the constraint must be applied
11061 -- to the full type.
11063 if Has_Unknown_Discriminants (Btyp)
11064 and then Present (Underlying_Type (Btyp))
11066 Btyp := Underlying_Type (Btyp);
11070 Make_Subtype_Indication (Loc,
11071 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11072 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11074 Def_Id := Create_Itype (Ekind (T), Related_Node);
11077 Make_Subtype_Declaration (Loc,
11078 Defining_Identifier => Def_Id,
11079 Subtype_Indication => Indic);
11081 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11083 -- Itypes must be analyzed with checks off (see package Itypes)
11085 Analyze (Subtyp_Decl, Suppress => All_Checks);
11090 ---------------------
11091 -- Get_Discr_Value --
11092 ---------------------
11094 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11099 -- The discriminant may be declared for the type, in which case we
11100 -- find it by iterating over the list of discriminants. If the
11101 -- discriminant is inherited from a parent type, it appears as the
11102 -- corresponding discriminant of the current type. This will be the
11103 -- case when constraining an inherited component whose constraint is
11104 -- given by a discriminant of the parent.
11106 D := First_Discriminant (Typ);
11107 E := First_Elmt (Constraints);
11109 while Present (D) loop
11110 if D = Entity (Discrim)
11111 or else D = CR_Discriminant (Entity (Discrim))
11112 or else Corresponding_Discriminant (D) = Entity (Discrim)
11117 Next_Discriminant (D);
11121 -- The Corresponding_Discriminant mechanism is incomplete, because
11122 -- the correspondence between new and old discriminants is not one
11123 -- to one: one new discriminant can constrain several old ones. In
11124 -- that case, scan sequentially the stored_constraint, the list of
11125 -- discriminants of the parents, and the constraints.
11126 -- Previous code checked for the present of the Stored_Constraint
11127 -- list for the derived type, but did not use it at all. Should it
11128 -- be present when the component is a discriminated task type?
11130 if Is_Derived_Type (Typ)
11131 and then Scope (Entity (Discrim)) = Etype (Typ)
11133 D := First_Discriminant (Etype (Typ));
11134 E := First_Elmt (Constraints);
11135 while Present (D) loop
11136 if D = Entity (Discrim) then
11140 Next_Discriminant (D);
11145 -- Something is wrong if we did not find the value
11147 raise Program_Error;
11148 end Get_Discr_Value;
11150 ---------------------
11151 -- Is_Discriminant --
11152 ---------------------
11154 function Is_Discriminant (Expr : Node_Id) return Boolean is
11155 Discrim_Scope : Entity_Id;
11158 if Denotes_Discriminant (Expr) then
11159 Discrim_Scope := Scope (Entity (Expr));
11161 -- Either we have a reference to one of Typ's discriminants,
11163 pragma Assert (Discrim_Scope = Typ
11165 -- or to the discriminants of the parent type, in the case
11166 -- of a derivation of a tagged type with variants.
11168 or else Discrim_Scope = Etype (Typ)
11169 or else Full_View (Discrim_Scope) = Etype (Typ)
11171 -- or same as above for the case where the discriminants
11172 -- were declared in Typ's private view.
11174 or else (Is_Private_Type (Discrim_Scope)
11175 and then Chars (Discrim_Scope) = Chars (Typ))
11177 -- or else we are deriving from the full view and the
11178 -- discriminant is declared in the private entity.
11180 or else (Is_Private_Type (Typ)
11181 and then Chars (Discrim_Scope) = Chars (Typ))
11183 -- Or we are constrained the corresponding record of a
11184 -- synchronized type that completes a private declaration.
11186 or else (Is_Concurrent_Record_Type (Typ)
11188 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11190 -- or we have a class-wide type, in which case make sure the
11191 -- discriminant found belongs to the root type.
11193 or else (Is_Class_Wide_Type (Typ)
11194 and then Etype (Typ) = Discrim_Scope));
11199 -- In all other cases we have something wrong
11202 end Is_Discriminant;
11204 -- Start of processing for Constrain_Component_Type
11207 if Nkind (Parent (Comp)) = N_Component_Declaration
11208 and then Comes_From_Source (Parent (Comp))
11209 and then Comes_From_Source
11210 (Subtype_Indication (Component_Definition (Parent (Comp))))
11213 (Subtype_Indication (Component_Definition (Parent (Comp))))
11215 return Compon_Type;
11217 elsif Is_Array_Type (Compon_Type) then
11218 return Build_Constrained_Array_Type (Compon_Type);
11220 elsif Has_Discriminants (Compon_Type) then
11221 return Build_Constrained_Discriminated_Type (Compon_Type);
11223 elsif Is_Access_Type (Compon_Type) then
11224 return Build_Constrained_Access_Type (Compon_Type);
11227 return Compon_Type;
11229 end Constrain_Component_Type;
11231 --------------------------
11232 -- Constrain_Concurrent --
11233 --------------------------
11235 -- For concurrent types, the associated record value type carries the same
11236 -- discriminants, so when we constrain a concurrent type, we must constrain
11237 -- the corresponding record type as well.
11239 procedure Constrain_Concurrent
11240 (Def_Id : in out Entity_Id;
11242 Related_Nod : Node_Id;
11243 Related_Id : Entity_Id;
11244 Suffix : Character)
11246 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
11250 if Ekind (T_Ent) in Access_Kind then
11251 T_Ent := Designated_Type (T_Ent);
11254 T_Val := Corresponding_Record_Type (T_Ent);
11256 if Present (T_Val) then
11258 if No (Def_Id) then
11259 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11262 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11264 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11265 Set_Corresponding_Record_Type (Def_Id,
11266 Constrain_Corresponding_Record
11267 (Def_Id, T_Val, Related_Nod, Related_Id));
11270 -- If there is no associated record, expansion is disabled and this
11271 -- is a generic context. Create a subtype in any case, so that
11272 -- semantic analysis can proceed.
11274 if No (Def_Id) then
11275 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11278 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11280 end Constrain_Concurrent;
11282 ------------------------------------
11283 -- Constrain_Corresponding_Record --
11284 ------------------------------------
11286 function Constrain_Corresponding_Record
11287 (Prot_Subt : Entity_Id;
11288 Corr_Rec : Entity_Id;
11289 Related_Nod : Node_Id;
11290 Related_Id : Entity_Id) return Entity_Id
11292 T_Sub : constant Entity_Id :=
11293 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11296 Set_Etype (T_Sub, Corr_Rec);
11297 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11298 Set_Is_Constrained (T_Sub, True);
11299 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11300 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11302 -- As elsewhere, we do not want to create a freeze node for this itype
11303 -- if it is created for a constrained component of an enclosing record
11304 -- because references to outer discriminants will appear out of scope.
11306 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11307 Conditional_Delay (T_Sub, Corr_Rec);
11309 Set_Is_Frozen (T_Sub);
11312 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11313 Set_Discriminant_Constraint
11314 (T_Sub, Discriminant_Constraint (Prot_Subt));
11315 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11316 Create_Constrained_Components
11317 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11320 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11323 end Constrain_Corresponding_Record;
11325 -----------------------
11326 -- Constrain_Decimal --
11327 -----------------------
11329 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11330 T : constant Entity_Id := Entity (Subtype_Mark (S));
11331 C : constant Node_Id := Constraint (S);
11332 Loc : constant Source_Ptr := Sloc (C);
11333 Range_Expr : Node_Id;
11334 Digits_Expr : Node_Id;
11339 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11341 if Nkind (C) = N_Range_Constraint then
11342 Range_Expr := Range_Expression (C);
11343 Digits_Val := Digits_Value (T);
11346 pragma Assert (Nkind (C) = N_Digits_Constraint);
11348 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11350 Digits_Expr := Digits_Expression (C);
11351 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11353 Check_Digits_Expression (Digits_Expr);
11354 Digits_Val := Expr_Value (Digits_Expr);
11356 if Digits_Val > Digits_Value (T) then
11358 ("digits expression is incompatible with subtype", C);
11359 Digits_Val := Digits_Value (T);
11362 if Present (Range_Constraint (C)) then
11363 Range_Expr := Range_Expression (Range_Constraint (C));
11365 Range_Expr := Empty;
11369 Set_Etype (Def_Id, Base_Type (T));
11370 Set_Size_Info (Def_Id, (T));
11371 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11372 Set_Delta_Value (Def_Id, Delta_Value (T));
11373 Set_Scale_Value (Def_Id, Scale_Value (T));
11374 Set_Small_Value (Def_Id, Small_Value (T));
11375 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11376 Set_Digits_Value (Def_Id, Digits_Val);
11378 -- Manufacture range from given digits value if no range present
11380 if No (Range_Expr) then
11381 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11385 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11387 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11390 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11391 Set_Discrete_RM_Size (Def_Id);
11393 -- Unconditionally delay the freeze, since we cannot set size
11394 -- information in all cases correctly until the freeze point.
11396 Set_Has_Delayed_Freeze (Def_Id);
11397 end Constrain_Decimal;
11399 ----------------------------------
11400 -- Constrain_Discriminated_Type --
11401 ----------------------------------
11403 procedure Constrain_Discriminated_Type
11404 (Def_Id : Entity_Id;
11406 Related_Nod : Node_Id;
11407 For_Access : Boolean := False)
11409 E : constant Entity_Id := Entity (Subtype_Mark (S));
11412 Elist : Elist_Id := New_Elmt_List;
11414 procedure Fixup_Bad_Constraint;
11415 -- This is called after finding a bad constraint, and after having
11416 -- posted an appropriate error message. The mission is to leave the
11417 -- entity T in as reasonable state as possible!
11419 --------------------------
11420 -- Fixup_Bad_Constraint --
11421 --------------------------
11423 procedure Fixup_Bad_Constraint is
11425 -- Set a reasonable Ekind for the entity. For an incomplete type,
11426 -- we can't do much, but for other types, we can set the proper
11427 -- corresponding subtype kind.
11429 if Ekind (T) = E_Incomplete_Type then
11430 Set_Ekind (Def_Id, Ekind (T));
11432 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11435 -- Set Etype to the known type, to reduce chances of cascaded errors
11437 Set_Etype (Def_Id, E);
11438 Set_Error_Posted (Def_Id);
11439 end Fixup_Bad_Constraint;
11441 -- Start of processing for Constrain_Discriminated_Type
11444 C := Constraint (S);
11446 -- A discriminant constraint is only allowed in a subtype indication,
11447 -- after a subtype mark. This subtype mark must denote either a type
11448 -- with discriminants, or an access type whose designated type is a
11449 -- type with discriminants. A discriminant constraint specifies the
11450 -- values of these discriminants (RM 3.7.2(5)).
11452 T := Base_Type (Entity (Subtype_Mark (S)));
11454 if Ekind (T) in Access_Kind then
11455 T := Designated_Type (T);
11458 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11459 -- Avoid generating an error for access-to-incomplete subtypes.
11461 if Ada_Version >= Ada_2005
11462 and then Ekind (T) = E_Incomplete_Type
11463 and then Nkind (Parent (S)) = N_Subtype_Declaration
11464 and then not Is_Itype (Def_Id)
11466 -- A little sanity check, emit an error message if the type
11467 -- has discriminants to begin with. Type T may be a regular
11468 -- incomplete type or imported via a limited with clause.
11470 if Has_Discriminants (T)
11472 (From_With_Type (T)
11473 and then Present (Non_Limited_View (T))
11474 and then Nkind (Parent (Non_Limited_View (T))) =
11475 N_Full_Type_Declaration
11476 and then Present (Discriminant_Specifications
11477 (Parent (Non_Limited_View (T)))))
11480 ("(Ada 2005) incomplete subtype may not be constrained", C);
11482 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11485 Fixup_Bad_Constraint;
11488 -- Check that the type has visible discriminants. The type may be
11489 -- a private type with unknown discriminants whose full view has
11490 -- discriminants which are invisible.
11492 elsif not Has_Discriminants (T)
11494 (Has_Unknown_Discriminants (T)
11495 and then Is_Private_Type (T))
11497 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11498 Fixup_Bad_Constraint;
11501 elsif Is_Constrained (E)
11502 or else (Ekind (E) = E_Class_Wide_Subtype
11503 and then Present (Discriminant_Constraint (E)))
11505 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11506 Fixup_Bad_Constraint;
11510 -- T may be an unconstrained subtype (e.g. a generic actual).
11511 -- Constraint applies to the base type.
11513 T := Base_Type (T);
11515 Elist := Build_Discriminant_Constraints (T, S);
11517 -- If the list returned was empty we had an error in building the
11518 -- discriminant constraint. We have also already signalled an error
11519 -- in the incomplete type case
11521 if Is_Empty_Elmt_List (Elist) then
11522 Fixup_Bad_Constraint;
11526 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11527 end Constrain_Discriminated_Type;
11529 ---------------------------
11530 -- Constrain_Enumeration --
11531 ---------------------------
11533 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11534 T : constant Entity_Id := Entity (Subtype_Mark (S));
11535 C : constant Node_Id := Constraint (S);
11538 -- By default, consider that the enumeration subtype is in ALFA if the
11539 -- entity of its subtype mark is in ALFA. This is reversed later if the
11540 -- range of the subtype is not static.
11542 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11543 and then Is_In_ALFA (T)
11545 Set_Is_In_ALFA (Def_Id);
11548 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11550 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11552 Set_Etype (Def_Id, Base_Type (T));
11553 Set_Size_Info (Def_Id, (T));
11554 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11555 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11557 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11559 Set_Discrete_RM_Size (Def_Id);
11560 end Constrain_Enumeration;
11562 ----------------------
11563 -- Constrain_Float --
11564 ----------------------
11566 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11567 T : constant Entity_Id := Entity (Subtype_Mark (S));
11573 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11575 Set_Etype (Def_Id, Base_Type (T));
11576 Set_Size_Info (Def_Id, (T));
11577 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11579 -- Process the constraint
11581 C := Constraint (S);
11583 -- Digits constraint present
11585 if Nkind (C) = N_Digits_Constraint then
11587 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11588 Check_Restriction (No_Obsolescent_Features, C);
11590 if Warn_On_Obsolescent_Feature then
11592 ("subtype digits constraint is an " &
11593 "obsolescent feature (RM J.3(8))?", C);
11596 D := Digits_Expression (C);
11597 Analyze_And_Resolve (D, Any_Integer);
11598 Check_Digits_Expression (D);
11599 Set_Digits_Value (Def_Id, Expr_Value (D));
11601 -- Check that digits value is in range. Obviously we can do this
11602 -- at compile time, but it is strictly a runtime check, and of
11603 -- course there is an ACVC test that checks this!
11605 if Digits_Value (Def_Id) > Digits_Value (T) then
11606 Error_Msg_Uint_1 := Digits_Value (T);
11607 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11609 Make_Raise_Constraint_Error (Sloc (D),
11610 Reason => CE_Range_Check_Failed);
11611 Insert_Action (Declaration_Node (Def_Id), Rais);
11614 C := Range_Constraint (C);
11616 -- No digits constraint present
11619 Set_Digits_Value (Def_Id, Digits_Value (T));
11622 -- Range constraint present
11624 if Nkind (C) = N_Range_Constraint then
11625 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11627 -- No range constraint present
11630 pragma Assert (No (C));
11631 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11634 Set_Is_Constrained (Def_Id);
11635 end Constrain_Float;
11637 ---------------------
11638 -- Constrain_Index --
11639 ---------------------
11641 procedure Constrain_Index
11644 Related_Nod : Node_Id;
11645 Related_Id : Entity_Id;
11646 Suffix : Character;
11647 Suffix_Index : Nat)
11649 Def_Id : Entity_Id;
11650 R : Node_Id := Empty;
11651 T : constant Entity_Id := Etype (Index);
11654 if Nkind (S) = N_Range
11656 (Nkind (S) = N_Attribute_Reference
11657 and then Attribute_Name (S) = Name_Range)
11659 -- A Range attribute will be transformed into N_Range by Resolve
11665 Process_Range_Expr_In_Decl (R, T, Empty_List);
11667 if not Error_Posted (S)
11669 (Nkind (S) /= N_Range
11670 or else not Covers (T, (Etype (Low_Bound (S))))
11671 or else not Covers (T, (Etype (High_Bound (S)))))
11673 if Base_Type (T) /= Any_Type
11674 and then Etype (Low_Bound (S)) /= Any_Type
11675 and then Etype (High_Bound (S)) /= Any_Type
11677 Error_Msg_N ("range expected", S);
11681 elsif Nkind (S) = N_Subtype_Indication then
11683 -- The parser has verified that this is a discrete indication
11685 Resolve_Discrete_Subtype_Indication (S, T);
11686 R := Range_Expression (Constraint (S));
11688 -- Capture values of bounds and generate temporaries for them if
11689 -- needed, since checks may cause duplication of the expressions
11690 -- which must not be reevaluated.
11692 if Expander_Active then
11693 Force_Evaluation (Low_Bound (R));
11694 Force_Evaluation (High_Bound (R));
11697 elsif Nkind (S) = N_Discriminant_Association then
11699 -- Syntactically valid in subtype indication
11701 Error_Msg_N ("invalid index constraint", S);
11702 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11705 -- Subtype_Mark case, no anonymous subtypes to construct
11710 if Is_Entity_Name (S) then
11711 if not Is_Type (Entity (S)) then
11712 Error_Msg_N ("expect subtype mark for index constraint", S);
11714 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11715 Wrong_Type (S, Base_Type (T));
11717 -- Check error of subtype with predicate in index constraint
11720 Bad_Predicated_Subtype_Use
11721 ("subtype& has predicate, not allowed in index constraint",
11728 Error_Msg_N ("invalid index constraint", S);
11729 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11735 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11737 Set_Etype (Def_Id, Base_Type (T));
11739 if Is_Modular_Integer_Type (T) then
11740 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11742 elsif Is_Integer_Type (T) then
11743 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11746 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11747 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11748 Set_First_Literal (Def_Id, First_Literal (T));
11751 Set_Size_Info (Def_Id, (T));
11752 Set_RM_Size (Def_Id, RM_Size (T));
11753 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11755 Set_Scalar_Range (Def_Id, R);
11757 Set_Etype (S, Def_Id);
11758 Set_Discrete_RM_Size (Def_Id);
11759 end Constrain_Index;
11761 -----------------------
11762 -- Constrain_Integer --
11763 -----------------------
11765 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11766 T : constant Entity_Id := Entity (Subtype_Mark (S));
11767 C : constant Node_Id := Constraint (S);
11770 -- By default, consider that the integer subtype is in ALFA if the
11771 -- entity of its subtype mark is in ALFA. This is reversed later if the
11772 -- range of the subtype is not static.
11774 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11775 and then Is_In_ALFA (T)
11777 Set_Is_In_ALFA (Def_Id);
11780 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11782 if Is_Modular_Integer_Type (T) then
11783 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11785 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11788 Set_Etype (Def_Id, Base_Type (T));
11789 Set_Size_Info (Def_Id, (T));
11790 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11791 Set_Discrete_RM_Size (Def_Id);
11792 end Constrain_Integer;
11794 ------------------------------
11795 -- Constrain_Ordinary_Fixed --
11796 ------------------------------
11798 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11799 T : constant Entity_Id := Entity (Subtype_Mark (S));
11805 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11806 Set_Etype (Def_Id, Base_Type (T));
11807 Set_Size_Info (Def_Id, (T));
11808 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11809 Set_Small_Value (Def_Id, Small_Value (T));
11811 -- Process the constraint
11813 C := Constraint (S);
11815 -- Delta constraint present
11817 if Nkind (C) = N_Delta_Constraint then
11819 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11820 Check_Restriction (No_Obsolescent_Features, C);
11822 if Warn_On_Obsolescent_Feature then
11824 ("subtype delta constraint is an " &
11825 "obsolescent feature (RM J.3(7))?");
11828 D := Delta_Expression (C);
11829 Analyze_And_Resolve (D, Any_Real);
11830 Check_Delta_Expression (D);
11831 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11833 -- Check that delta value is in range. Obviously we can do this
11834 -- at compile time, but it is strictly a runtime check, and of
11835 -- course there is an ACVC test that checks this!
11837 if Delta_Value (Def_Id) < Delta_Value (T) then
11838 Error_Msg_N ("?delta value is too small", D);
11840 Make_Raise_Constraint_Error (Sloc (D),
11841 Reason => CE_Range_Check_Failed);
11842 Insert_Action (Declaration_Node (Def_Id), Rais);
11845 C := Range_Constraint (C);
11847 -- No delta constraint present
11850 Set_Delta_Value (Def_Id, Delta_Value (T));
11853 -- Range constraint present
11855 if Nkind (C) = N_Range_Constraint then
11856 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11858 -- No range constraint present
11861 pragma Assert (No (C));
11862 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11866 Set_Discrete_RM_Size (Def_Id);
11868 -- Unconditionally delay the freeze, since we cannot set size
11869 -- information in all cases correctly until the freeze point.
11871 Set_Has_Delayed_Freeze (Def_Id);
11872 end Constrain_Ordinary_Fixed;
11874 -----------------------
11875 -- Contain_Interface --
11876 -----------------------
11878 function Contain_Interface
11879 (Iface : Entity_Id;
11880 Ifaces : Elist_Id) return Boolean
11882 Iface_Elmt : Elmt_Id;
11885 if Present (Ifaces) then
11886 Iface_Elmt := First_Elmt (Ifaces);
11887 while Present (Iface_Elmt) loop
11888 if Node (Iface_Elmt) = Iface then
11892 Next_Elmt (Iface_Elmt);
11897 end Contain_Interface;
11899 ---------------------------
11900 -- Convert_Scalar_Bounds --
11901 ---------------------------
11903 procedure Convert_Scalar_Bounds
11905 Parent_Type : Entity_Id;
11906 Derived_Type : Entity_Id;
11909 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11916 -- Defend against previous errors
11918 if No (Scalar_Range (Derived_Type)) then
11922 Lo := Build_Scalar_Bound
11923 (Type_Low_Bound (Derived_Type),
11924 Parent_Type, Implicit_Base);
11926 Hi := Build_Scalar_Bound
11927 (Type_High_Bound (Derived_Type),
11928 Parent_Type, Implicit_Base);
11935 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11937 Set_Parent (Rng, N);
11938 Set_Scalar_Range (Derived_Type, Rng);
11940 -- Analyze the bounds
11942 Analyze_And_Resolve (Lo, Implicit_Base);
11943 Analyze_And_Resolve (Hi, Implicit_Base);
11945 -- Analyze the range itself, except that we do not analyze it if
11946 -- the bounds are real literals, and we have a fixed-point type.
11947 -- The reason for this is that we delay setting the bounds in this
11948 -- case till we know the final Small and Size values (see circuit
11949 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11951 if Is_Fixed_Point_Type (Parent_Type)
11952 and then Nkind (Lo) = N_Real_Literal
11953 and then Nkind (Hi) = N_Real_Literal
11957 -- Here we do the analysis of the range
11959 -- Note: we do this manually, since if we do a normal Analyze and
11960 -- Resolve call, there are problems with the conversions used for
11961 -- the derived type range.
11964 Set_Etype (Rng, Implicit_Base);
11965 Set_Analyzed (Rng, True);
11967 end Convert_Scalar_Bounds;
11969 -------------------
11970 -- Copy_And_Swap --
11971 -------------------
11973 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
11975 -- Initialize new full declaration entity by copying the pertinent
11976 -- fields of the corresponding private declaration entity.
11978 -- We temporarily set Ekind to a value appropriate for a type to
11979 -- avoid assert failures in Einfo from checking for setting type
11980 -- attributes on something that is not a type. Ekind (Priv) is an
11981 -- appropriate choice, since it allowed the attributes to be set
11982 -- in the first place. This Ekind value will be modified later.
11984 Set_Ekind (Full, Ekind (Priv));
11986 -- Also set Etype temporarily to Any_Type, again, in the absence
11987 -- of errors, it will be properly reset, and if there are errors,
11988 -- then we want a value of Any_Type to remain.
11990 Set_Etype (Full, Any_Type);
11992 -- Now start copying attributes
11994 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
11996 if Has_Discriminants (Full) then
11997 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
11998 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12001 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12002 Set_Homonym (Full, Homonym (Priv));
12003 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12004 Set_Is_Public (Full, Is_Public (Priv));
12005 Set_Is_Pure (Full, Is_Pure (Priv));
12006 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12007 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12008 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12009 Set_Has_Pragma_Unreferenced_Objects
12010 (Full, Has_Pragma_Unreferenced_Objects
12013 Conditional_Delay (Full, Priv);
12015 if Is_Tagged_Type (Full) then
12016 Set_Direct_Primitive_Operations (Full,
12017 Direct_Primitive_Operations (Priv));
12019 if Is_Base_Type (Priv) then
12020 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12024 Set_Is_Volatile (Full, Is_Volatile (Priv));
12025 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12026 Set_Scope (Full, Scope (Priv));
12027 Set_Next_Entity (Full, Next_Entity (Priv));
12028 Set_First_Entity (Full, First_Entity (Priv));
12029 Set_Last_Entity (Full, Last_Entity (Priv));
12031 -- If access types have been recorded for later handling, keep them in
12032 -- the full view so that they get handled when the full view freeze
12033 -- node is expanded.
12035 if Present (Freeze_Node (Priv))
12036 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12038 Ensure_Freeze_Node (Full);
12039 Set_Access_Types_To_Process
12040 (Freeze_Node (Full),
12041 Access_Types_To_Process (Freeze_Node (Priv)));
12044 -- Swap the two entities. Now Private is the full type entity and Full
12045 -- is the private one. They will be swapped back at the end of the
12046 -- private part. This swapping ensures that the entity that is visible
12047 -- in the private part is the full declaration.
12049 Exchange_Entities (Priv, Full);
12050 Append_Entity (Full, Scope (Full));
12053 -------------------------------------
12054 -- Copy_Array_Base_Type_Attributes --
12055 -------------------------------------
12057 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12059 Set_Component_Alignment (T1, Component_Alignment (T2));
12060 Set_Component_Type (T1, Component_Type (T2));
12061 Set_Component_Size (T1, Component_Size (T2));
12062 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12063 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12064 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12065 Set_Has_Task (T1, Has_Task (T2));
12066 Set_Is_Packed (T1, Is_Packed (T2));
12067 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12068 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12069 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12070 end Copy_Array_Base_Type_Attributes;
12072 -----------------------------------
12073 -- Copy_Array_Subtype_Attributes --
12074 -----------------------------------
12076 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12078 Set_Size_Info (T1, T2);
12080 Set_First_Index (T1, First_Index (T2));
12081 Set_Is_Aliased (T1, Is_Aliased (T2));
12082 Set_Is_Atomic (T1, Is_Atomic (T2));
12083 Set_Is_Volatile (T1, Is_Volatile (T2));
12084 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12085 Set_Is_Constrained (T1, Is_Constrained (T2));
12086 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12087 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12088 Set_Convention (T1, Convention (T2));
12089 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12090 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12091 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12092 end Copy_Array_Subtype_Attributes;
12094 -----------------------------------
12095 -- Create_Constrained_Components --
12096 -----------------------------------
12098 procedure Create_Constrained_Components
12100 Decl_Node : Node_Id;
12102 Constraints : Elist_Id)
12104 Loc : constant Source_Ptr := Sloc (Subt);
12105 Comp_List : constant Elist_Id := New_Elmt_List;
12106 Parent_Type : constant Entity_Id := Etype (Typ);
12107 Assoc_List : constant List_Id := New_List;
12108 Discr_Val : Elmt_Id;
12112 Is_Static : Boolean := True;
12114 procedure Collect_Fixed_Components (Typ : Entity_Id);
12115 -- Collect parent type components that do not appear in a variant part
12117 procedure Create_All_Components;
12118 -- Iterate over Comp_List to create the components of the subtype
12120 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12121 -- Creates a new component from Old_Compon, copying all the fields from
12122 -- it, including its Etype, inserts the new component in the Subt entity
12123 -- chain and returns the new component.
12125 function Is_Variant_Record (T : Entity_Id) return Boolean;
12126 -- If true, and discriminants are static, collect only components from
12127 -- variants selected by discriminant values.
12129 ------------------------------
12130 -- Collect_Fixed_Components --
12131 ------------------------------
12133 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12135 -- Build association list for discriminants, and find components of the
12136 -- variant part selected by the values of the discriminants.
12138 Old_C := First_Discriminant (Typ);
12139 Discr_Val := First_Elmt (Constraints);
12140 while Present (Old_C) loop
12141 Append_To (Assoc_List,
12142 Make_Component_Association (Loc,
12143 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12144 Expression => New_Copy (Node (Discr_Val))));
12146 Next_Elmt (Discr_Val);
12147 Next_Discriminant (Old_C);
12150 -- The tag, and the possible parent and controller components
12151 -- are unconditionally in the subtype.
12153 if Is_Tagged_Type (Typ)
12154 or else Has_Controlled_Component (Typ)
12156 Old_C := First_Component (Typ);
12157 while Present (Old_C) loop
12158 if Chars ((Old_C)) = Name_uTag
12159 or else Chars ((Old_C)) = Name_uParent
12160 or else Chars ((Old_C)) = Name_uController
12162 Append_Elmt (Old_C, Comp_List);
12165 Next_Component (Old_C);
12168 end Collect_Fixed_Components;
12170 ---------------------------
12171 -- Create_All_Components --
12172 ---------------------------
12174 procedure Create_All_Components is
12178 Comp := First_Elmt (Comp_List);
12179 while Present (Comp) loop
12180 Old_C := Node (Comp);
12181 New_C := Create_Component (Old_C);
12185 Constrain_Component_Type
12186 (Old_C, Subt, Decl_Node, Typ, Constraints));
12187 Set_Is_Public (New_C, Is_Public (Subt));
12191 end Create_All_Components;
12193 ----------------------
12194 -- Create_Component --
12195 ----------------------
12197 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12198 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12201 if Ekind (Old_Compon) = E_Discriminant
12202 and then Is_Completely_Hidden (Old_Compon)
12204 -- This is a shadow discriminant created for a discriminant of
12205 -- the parent type, which needs to be present in the subtype.
12206 -- Give the shadow discriminant an internal name that cannot
12207 -- conflict with that of visible components.
12209 Set_Chars (New_Compon, New_Internal_Name ('C'));
12212 -- Set the parent so we have a proper link for freezing etc. This is
12213 -- not a real parent pointer, since of course our parent does not own
12214 -- up to us and reference us, we are an illegitimate child of the
12215 -- original parent!
12217 Set_Parent (New_Compon, Parent (Old_Compon));
12219 -- If the old component's Esize was already determined and is a
12220 -- static value, then the new component simply inherits it. Otherwise
12221 -- the old component's size may require run-time determination, but
12222 -- the new component's size still might be statically determinable
12223 -- (if, for example it has a static constraint). In that case we want
12224 -- Layout_Type to recompute the component's size, so we reset its
12225 -- size and positional fields.
12227 if Frontend_Layout_On_Target
12228 and then not Known_Static_Esize (Old_Compon)
12230 Set_Esize (New_Compon, Uint_0);
12231 Init_Normalized_First_Bit (New_Compon);
12232 Init_Normalized_Position (New_Compon);
12233 Init_Normalized_Position_Max (New_Compon);
12236 -- We do not want this node marked as Comes_From_Source, since
12237 -- otherwise it would get first class status and a separate cross-
12238 -- reference line would be generated. Illegitimate children do not
12239 -- rate such recognition.
12241 Set_Comes_From_Source (New_Compon, False);
12243 -- But it is a real entity, and a birth certificate must be properly
12244 -- registered by entering it into the entity list.
12246 Enter_Name (New_Compon);
12249 end Create_Component;
12251 -----------------------
12252 -- Is_Variant_Record --
12253 -----------------------
12255 function Is_Variant_Record (T : Entity_Id) return Boolean is
12257 return Nkind (Parent (T)) = N_Full_Type_Declaration
12258 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12259 and then Present (Component_List (Type_Definition (Parent (T))))
12262 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12263 end Is_Variant_Record;
12265 -- Start of processing for Create_Constrained_Components
12268 pragma Assert (Subt /= Base_Type (Subt));
12269 pragma Assert (Typ = Base_Type (Typ));
12271 Set_First_Entity (Subt, Empty);
12272 Set_Last_Entity (Subt, Empty);
12274 -- Check whether constraint is fully static, in which case we can
12275 -- optimize the list of components.
12277 Discr_Val := First_Elmt (Constraints);
12278 while Present (Discr_Val) loop
12279 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12280 Is_Static := False;
12284 Next_Elmt (Discr_Val);
12287 Set_Has_Static_Discriminants (Subt, Is_Static);
12291 -- Inherit the discriminants of the parent type
12293 Add_Discriminants : declare
12299 Old_C := First_Discriminant (Typ);
12301 while Present (Old_C) loop
12302 Num_Disc := Num_Disc + 1;
12303 New_C := Create_Component (Old_C);
12304 Set_Is_Public (New_C, Is_Public (Subt));
12305 Next_Discriminant (Old_C);
12308 -- For an untagged derived subtype, the number of discriminants may
12309 -- be smaller than the number of inherited discriminants, because
12310 -- several of them may be renamed by a single new discriminant or
12311 -- constrained. In this case, add the hidden discriminants back into
12312 -- the subtype, because they need to be present if the optimizer of
12313 -- the GCC 4.x back-end decides to break apart assignments between
12314 -- objects using the parent view into member-wise assignments.
12318 if Is_Derived_Type (Typ)
12319 and then not Is_Tagged_Type (Typ)
12321 Old_C := First_Stored_Discriminant (Typ);
12323 while Present (Old_C) loop
12324 Num_Gird := Num_Gird + 1;
12325 Next_Stored_Discriminant (Old_C);
12329 if Num_Gird > Num_Disc then
12331 -- Find out multiple uses of new discriminants, and add hidden
12332 -- components for the extra renamed discriminants. We recognize
12333 -- multiple uses through the Corresponding_Discriminant of a
12334 -- new discriminant: if it constrains several old discriminants,
12335 -- this field points to the last one in the parent type. The
12336 -- stored discriminants of the derived type have the same name
12337 -- as those of the parent.
12341 New_Discr : Entity_Id;
12342 Old_Discr : Entity_Id;
12345 Constr := First_Elmt (Stored_Constraint (Typ));
12346 Old_Discr := First_Stored_Discriminant (Typ);
12347 while Present (Constr) loop
12348 if Is_Entity_Name (Node (Constr))
12349 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12351 New_Discr := Entity (Node (Constr));
12353 if Chars (Corresponding_Discriminant (New_Discr)) /=
12356 -- The new discriminant has been used to rename a
12357 -- subsequent old discriminant. Introduce a shadow
12358 -- component for the current old discriminant.
12360 New_C := Create_Component (Old_Discr);
12361 Set_Original_Record_Component (New_C, Old_Discr);
12365 -- The constraint has eliminated the old discriminant.
12366 -- Introduce a shadow component.
12368 New_C := Create_Component (Old_Discr);
12369 Set_Original_Record_Component (New_C, Old_Discr);
12372 Next_Elmt (Constr);
12373 Next_Stored_Discriminant (Old_Discr);
12377 end Add_Discriminants;
12380 and then Is_Variant_Record (Typ)
12382 Collect_Fixed_Components (Typ);
12384 Gather_Components (
12386 Component_List (Type_Definition (Parent (Typ))),
12387 Governed_By => Assoc_List,
12389 Report_Errors => Errors);
12390 pragma Assert (not Errors);
12392 Create_All_Components;
12394 -- If the subtype declaration is created for a tagged type derivation
12395 -- with constraints, we retrieve the record definition of the parent
12396 -- type to select the components of the proper variant.
12399 and then Is_Tagged_Type (Typ)
12400 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12402 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12403 and then Is_Variant_Record (Parent_Type)
12405 Collect_Fixed_Components (Typ);
12407 Gather_Components (
12409 Component_List (Type_Definition (Parent (Parent_Type))),
12410 Governed_By => Assoc_List,
12412 Report_Errors => Errors);
12413 pragma Assert (not Errors);
12415 -- If the tagged derivation has a type extension, collect all the
12416 -- new components therein.
12419 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12421 Old_C := First_Component (Typ);
12422 while Present (Old_C) loop
12423 if Original_Record_Component (Old_C) = Old_C
12424 and then Chars (Old_C) /= Name_uTag
12425 and then Chars (Old_C) /= Name_uParent
12426 and then Chars (Old_C) /= Name_uController
12428 Append_Elmt (Old_C, Comp_List);
12431 Next_Component (Old_C);
12435 Create_All_Components;
12438 -- If discriminants are not static, or if this is a multi-level type
12439 -- extension, we have to include all components of the parent type.
12441 Old_C := First_Component (Typ);
12442 while Present (Old_C) loop
12443 New_C := Create_Component (Old_C);
12447 Constrain_Component_Type
12448 (Old_C, Subt, Decl_Node, Typ, Constraints));
12449 Set_Is_Public (New_C, Is_Public (Subt));
12451 Next_Component (Old_C);
12456 end Create_Constrained_Components;
12458 ------------------------------------------
12459 -- Decimal_Fixed_Point_Type_Declaration --
12460 ------------------------------------------
12462 procedure Decimal_Fixed_Point_Type_Declaration
12466 Loc : constant Source_Ptr := Sloc (Def);
12467 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12468 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12469 Implicit_Base : Entity_Id;
12476 Check_SPARK_Restriction
12477 ("decimal fixed point type is not allowed", Def);
12478 Check_Restriction (No_Fixed_Point, Def);
12480 -- Create implicit base type
12483 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12484 Set_Etype (Implicit_Base, Implicit_Base);
12486 -- Analyze and process delta expression
12488 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12490 Check_Delta_Expression (Delta_Expr);
12491 Delta_Val := Expr_Value_R (Delta_Expr);
12493 -- Check delta is power of 10, and determine scale value from it
12499 Scale_Val := Uint_0;
12502 if Val < Ureal_1 then
12503 while Val < Ureal_1 loop
12504 Val := Val * Ureal_10;
12505 Scale_Val := Scale_Val + 1;
12508 if Scale_Val > 18 then
12509 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12510 Scale_Val := UI_From_Int (+18);
12514 while Val > Ureal_1 loop
12515 Val := Val / Ureal_10;
12516 Scale_Val := Scale_Val - 1;
12519 if Scale_Val < -18 then
12520 Error_Msg_N ("scale is less than minimum value of -18", Def);
12521 Scale_Val := UI_From_Int (-18);
12525 if Val /= Ureal_1 then
12526 Error_Msg_N ("delta expression must be a power of 10", Def);
12527 Delta_Val := Ureal_10 ** (-Scale_Val);
12531 -- Set delta, scale and small (small = delta for decimal type)
12533 Set_Delta_Value (Implicit_Base, Delta_Val);
12534 Set_Scale_Value (Implicit_Base, Scale_Val);
12535 Set_Small_Value (Implicit_Base, Delta_Val);
12537 -- Analyze and process digits expression
12539 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12540 Check_Digits_Expression (Digs_Expr);
12541 Digs_Val := Expr_Value (Digs_Expr);
12543 if Digs_Val > 18 then
12544 Digs_Val := UI_From_Int (+18);
12545 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12548 Set_Digits_Value (Implicit_Base, Digs_Val);
12549 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12551 -- Set range of base type from digits value for now. This will be
12552 -- expanded to represent the true underlying base range by Freeze.
12554 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12556 -- Note: We leave size as zero for now, size will be set at freeze
12557 -- time. We have to do this for ordinary fixed-point, because the size
12558 -- depends on the specified small, and we might as well do the same for
12559 -- decimal fixed-point.
12561 pragma Assert (Esize (Implicit_Base) = Uint_0);
12563 -- If there are bounds given in the declaration use them as the
12564 -- bounds of the first named subtype.
12566 if Present (Real_Range_Specification (Def)) then
12568 RRS : constant Node_Id := Real_Range_Specification (Def);
12569 Low : constant Node_Id := Low_Bound (RRS);
12570 High : constant Node_Id := High_Bound (RRS);
12575 Analyze_And_Resolve (Low, Any_Real);
12576 Analyze_And_Resolve (High, Any_Real);
12577 Check_Real_Bound (Low);
12578 Check_Real_Bound (High);
12579 Low_Val := Expr_Value_R (Low);
12580 High_Val := Expr_Value_R (High);
12582 if Low_Val < (-Bound_Val) then
12584 ("range low bound too small for digits value", Low);
12585 Low_Val := -Bound_Val;
12588 if High_Val > Bound_Val then
12590 ("range high bound too large for digits value", High);
12591 High_Val := Bound_Val;
12594 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12597 -- If no explicit range, use range that corresponds to given
12598 -- digits value. This will end up as the final range for the
12602 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12605 -- Complete entity for first subtype
12607 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12608 Set_Etype (T, Implicit_Base);
12609 Set_Size_Info (T, Implicit_Base);
12610 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12611 Set_Digits_Value (T, Digs_Val);
12612 Set_Delta_Value (T, Delta_Val);
12613 Set_Small_Value (T, Delta_Val);
12614 Set_Scale_Value (T, Scale_Val);
12615 Set_Is_Constrained (T);
12616 end Decimal_Fixed_Point_Type_Declaration;
12618 -----------------------------------
12619 -- Derive_Progenitor_Subprograms --
12620 -----------------------------------
12622 procedure Derive_Progenitor_Subprograms
12623 (Parent_Type : Entity_Id;
12624 Tagged_Type : Entity_Id)
12629 Iface_Elmt : Elmt_Id;
12630 Iface_Subp : Entity_Id;
12631 New_Subp : Entity_Id := Empty;
12632 Prim_Elmt : Elmt_Id;
12637 pragma Assert (Ada_Version >= Ada_2005
12638 and then Is_Record_Type (Tagged_Type)
12639 and then Is_Tagged_Type (Tagged_Type)
12640 and then Has_Interfaces (Tagged_Type));
12642 -- Step 1: Transfer to the full-view primitives associated with the
12643 -- partial-view that cover interface primitives. Conceptually this
12644 -- work should be done later by Process_Full_View; done here to
12645 -- simplify its implementation at later stages. It can be safely
12646 -- done here because interfaces must be visible in the partial and
12647 -- private view (RM 7.3(7.3/2)).
12649 -- Small optimization: This work is only required if the parent is
12650 -- abstract. If the tagged type is not abstract, it cannot have
12651 -- abstract primitives (the only entities in the list of primitives of
12652 -- non-abstract tagged types that can reference abstract primitives
12653 -- through its Alias attribute are the internal entities that have
12654 -- attribute Interface_Alias, and these entities are generated later
12655 -- by Add_Internal_Interface_Entities).
12657 if In_Private_Part (Current_Scope)
12658 and then Is_Abstract_Type (Parent_Type)
12660 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12661 while Present (Elmt) loop
12662 Subp := Node (Elmt);
12664 -- At this stage it is not possible to have entities in the list
12665 -- of primitives that have attribute Interface_Alias
12667 pragma Assert (No (Interface_Alias (Subp)));
12669 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12671 if Is_Interface (Typ) then
12672 E := Find_Primitive_Covering_Interface
12673 (Tagged_Type => Tagged_Type,
12674 Iface_Prim => Subp);
12677 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12679 Replace_Elmt (Elmt, E);
12680 Remove_Homonym (Subp);
12688 -- Step 2: Add primitives of progenitors that are not implemented by
12689 -- parents of Tagged_Type
12691 if Present (Interfaces (Base_Type (Tagged_Type))) then
12692 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12693 while Present (Iface_Elmt) loop
12694 Iface := Node (Iface_Elmt);
12696 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12697 while Present (Prim_Elmt) loop
12698 Iface_Subp := Node (Prim_Elmt);
12700 -- Exclude derivation of predefined primitives except those
12701 -- that come from source. Required to catch declarations of
12702 -- equality operators of interfaces. For example:
12704 -- type Iface is interface;
12705 -- function "=" (Left, Right : Iface) return Boolean;
12707 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12708 or else Comes_From_Source (Iface_Subp)
12710 E := Find_Primitive_Covering_Interface
12711 (Tagged_Type => Tagged_Type,
12712 Iface_Prim => Iface_Subp);
12714 -- If not found we derive a new primitive leaving its alias
12715 -- attribute referencing the interface primitive
12719 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12721 -- Ada 2012 (AI05-0197): If the covering primitive's name
12722 -- differs from the name of the interface primitive then it
12723 -- is a private primitive inherited from a parent type. In
12724 -- such case, given that Tagged_Type covers the interface,
12725 -- the inherited private primitive becomes visible. For such
12726 -- purpose we add a new entity that renames the inherited
12727 -- private primitive.
12729 elsif Chars (E) /= Chars (Iface_Subp) then
12730 pragma Assert (Has_Suffix (E, 'P'));
12732 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12733 Set_Alias (New_Subp, E);
12734 Set_Is_Abstract_Subprogram (New_Subp,
12735 Is_Abstract_Subprogram (E));
12737 -- Propagate to the full view interface entities associated
12738 -- with the partial view
12740 elsif In_Private_Part (Current_Scope)
12741 and then Present (Alias (E))
12742 and then Alias (E) = Iface_Subp
12744 List_Containing (Parent (E)) /=
12745 Private_Declarations
12747 (Unit_Declaration_Node (Current_Scope)))
12749 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12753 Next_Elmt (Prim_Elmt);
12756 Next_Elmt (Iface_Elmt);
12759 end Derive_Progenitor_Subprograms;
12761 -----------------------
12762 -- Derive_Subprogram --
12763 -----------------------
12765 procedure Derive_Subprogram
12766 (New_Subp : in out Entity_Id;
12767 Parent_Subp : Entity_Id;
12768 Derived_Type : Entity_Id;
12769 Parent_Type : Entity_Id;
12770 Actual_Subp : Entity_Id := Empty)
12772 Formal : Entity_Id;
12773 -- Formal parameter of parent primitive operation
12775 Formal_Of_Actual : Entity_Id;
12776 -- Formal parameter of actual operation, when the derivation is to
12777 -- create a renaming for a primitive operation of an actual in an
12780 New_Formal : Entity_Id;
12781 -- Formal of inherited operation
12783 Visible_Subp : Entity_Id := Parent_Subp;
12785 function Is_Private_Overriding return Boolean;
12786 -- If Subp is a private overriding of a visible operation, the inherited
12787 -- operation derives from the overridden op (even though its body is the
12788 -- overriding one) and the inherited operation is visible now. See
12789 -- sem_disp to see the full details of the handling of the overridden
12790 -- subprogram, which is removed from the list of primitive operations of
12791 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12792 -- and used to diagnose abstract operations that need overriding in the
12795 procedure Replace_Type (Id, New_Id : Entity_Id);
12796 -- When the type is an anonymous access type, create a new access type
12797 -- designating the derived type.
12799 procedure Set_Derived_Name;
12800 -- This procedure sets the appropriate Chars name for New_Subp. This
12801 -- is normally just a copy of the parent name. An exception arises for
12802 -- type support subprograms, where the name is changed to reflect the
12803 -- name of the derived type, e.g. if type foo is derived from type bar,
12804 -- then a procedure barDA is derived with a name fooDA.
12806 ---------------------------
12807 -- Is_Private_Overriding --
12808 ---------------------------
12810 function Is_Private_Overriding return Boolean is
12814 -- If the parent is not a dispatching operation there is no
12815 -- need to investigate overridings
12817 if not Is_Dispatching_Operation (Parent_Subp) then
12821 -- The visible operation that is overridden is a homonym of the
12822 -- parent subprogram. We scan the homonym chain to find the one
12823 -- whose alias is the subprogram we are deriving.
12825 Prev := Current_Entity (Parent_Subp);
12826 while Present (Prev) loop
12827 if Ekind (Prev) = Ekind (Parent_Subp)
12828 and then Alias (Prev) = Parent_Subp
12829 and then Scope (Parent_Subp) = Scope (Prev)
12830 and then not Is_Hidden (Prev)
12832 Visible_Subp := Prev;
12836 Prev := Homonym (Prev);
12840 end Is_Private_Overriding;
12846 procedure Replace_Type (Id, New_Id : Entity_Id) is
12847 Acc_Type : Entity_Id;
12848 Par : constant Node_Id := Parent (Derived_Type);
12851 -- When the type is an anonymous access type, create a new access
12852 -- type designating the derived type. This itype must be elaborated
12853 -- at the point of the derivation, not on subsequent calls that may
12854 -- be out of the proper scope for Gigi, so we insert a reference to
12855 -- it after the derivation.
12857 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12859 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12862 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12863 and then Present (Full_View (Desig_Typ))
12864 and then not Is_Private_Type (Parent_Type)
12866 Desig_Typ := Full_View (Desig_Typ);
12869 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12871 -- Ada 2005 (AI-251): Handle also derivations of abstract
12872 -- interface primitives.
12874 or else (Is_Interface (Desig_Typ)
12875 and then not Is_Class_Wide_Type (Desig_Typ))
12877 Acc_Type := New_Copy (Etype (Id));
12878 Set_Etype (Acc_Type, Acc_Type);
12879 Set_Scope (Acc_Type, New_Subp);
12881 -- Compute size of anonymous access type
12883 if Is_Array_Type (Desig_Typ)
12884 and then not Is_Constrained (Desig_Typ)
12886 Init_Size (Acc_Type, 2 * System_Address_Size);
12888 Init_Size (Acc_Type, System_Address_Size);
12891 Init_Alignment (Acc_Type);
12892 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12894 Set_Etype (New_Id, Acc_Type);
12895 Set_Scope (New_Id, New_Subp);
12897 -- Create a reference to it
12898 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12901 Set_Etype (New_Id, Etype (Id));
12905 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12907 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12908 and then Present (Full_View (Etype (Id)))
12910 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12912 -- Constraint checks on formals are generated during expansion,
12913 -- based on the signature of the original subprogram. The bounds
12914 -- of the derived type are not relevant, and thus we can use
12915 -- the base type for the formals. However, the return type may be
12916 -- used in a context that requires that the proper static bounds
12917 -- be used (a case statement, for example) and for those cases
12918 -- we must use the derived type (first subtype), not its base.
12920 -- If the derived_type_definition has no constraints, we know that
12921 -- the derived type has the same constraints as the first subtype
12922 -- of the parent, and we can also use it rather than its base,
12923 -- which can lead to more efficient code.
12925 if Etype (Id) = Parent_Type then
12926 if Is_Scalar_Type (Parent_Type)
12928 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12930 Set_Etype (New_Id, Derived_Type);
12932 elsif Nkind (Par) = N_Full_Type_Declaration
12934 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12937 (Subtype_Indication (Type_Definition (Par)))
12939 Set_Etype (New_Id, Derived_Type);
12942 Set_Etype (New_Id, Base_Type (Derived_Type));
12946 Set_Etype (New_Id, Base_Type (Derived_Type));
12950 Set_Etype (New_Id, Etype (Id));
12954 ----------------------
12955 -- Set_Derived_Name --
12956 ----------------------
12958 procedure Set_Derived_Name is
12959 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
12961 if Nm = TSS_Null then
12962 Set_Chars (New_Subp, Chars (Parent_Subp));
12964 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
12966 end Set_Derived_Name;
12968 -- Start of processing for Derive_Subprogram
12972 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
12973 Set_Ekind (New_Subp, Ekind (Parent_Subp));
12975 -- Check whether the inherited subprogram is a private operation that
12976 -- should be inherited but not yet made visible. Such subprograms can
12977 -- become visible at a later point (e.g., the private part of a public
12978 -- child unit) via Declare_Inherited_Private_Subprograms. If the
12979 -- following predicate is true, then this is not such a private
12980 -- operation and the subprogram simply inherits the name of the parent
12981 -- subprogram. Note the special check for the names of controlled
12982 -- operations, which are currently exempted from being inherited with
12983 -- a hidden name because they must be findable for generation of
12984 -- implicit run-time calls.
12986 if not Is_Hidden (Parent_Subp)
12987 or else Is_Internal (Parent_Subp)
12988 or else Is_Private_Overriding
12989 or else Is_Internal_Name (Chars (Parent_Subp))
12990 or else Chars (Parent_Subp) = Name_Initialize
12991 or else Chars (Parent_Subp) = Name_Adjust
12992 or else Chars (Parent_Subp) = Name_Finalize
12996 -- An inherited dispatching equality will be overridden by an internally
12997 -- generated one, or by an explicit one, so preserve its name and thus
12998 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
12999 -- private operation it may become invisible if the full view has
13000 -- progenitors, and the dispatch table will be malformed.
13001 -- We check that the type is limited to handle the anomalous declaration
13002 -- of Limited_Controlled, which is derived from a non-limited type, and
13003 -- which is handled specially elsewhere as well.
13005 elsif Chars (Parent_Subp) = Name_Op_Eq
13006 and then Is_Dispatching_Operation (Parent_Subp)
13007 and then Etype (Parent_Subp) = Standard_Boolean
13008 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13010 Etype (First_Formal (Parent_Subp)) =
13011 Etype (Next_Formal (First_Formal (Parent_Subp)))
13015 -- If parent is hidden, this can be a regular derivation if the
13016 -- parent is immediately visible in a non-instantiating context,
13017 -- or if we are in the private part of an instance. This test
13018 -- should still be refined ???
13020 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13021 -- operation as a non-visible operation in cases where the parent
13022 -- subprogram might not be visible now, but was visible within the
13023 -- original generic, so it would be wrong to make the inherited
13024 -- subprogram non-visible now. (Not clear if this test is fully
13025 -- correct; are there any cases where we should declare the inherited
13026 -- operation as not visible to avoid it being overridden, e.g., when
13027 -- the parent type is a generic actual with private primitives ???)
13029 -- (they should be treated the same as other private inherited
13030 -- subprograms, but it's not clear how to do this cleanly). ???
13032 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13033 and then Is_Immediately_Visible (Parent_Subp)
13034 and then not In_Instance)
13035 or else In_Instance_Not_Visible
13039 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13040 -- overrides an interface primitive because interface primitives
13041 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13043 elsif Ada_Version >= Ada_2005
13044 and then Is_Dispatching_Operation (Parent_Subp)
13045 and then Covers_Some_Interface (Parent_Subp)
13049 -- Otherwise, the type is inheriting a private operation, so enter
13050 -- it with a special name so it can't be overridden.
13053 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13056 Set_Parent (New_Subp, Parent (Derived_Type));
13058 if Present (Actual_Subp) then
13059 Replace_Type (Actual_Subp, New_Subp);
13061 Replace_Type (Parent_Subp, New_Subp);
13064 Conditional_Delay (New_Subp, Parent_Subp);
13066 -- If we are creating a renaming for a primitive operation of an
13067 -- actual of a generic derived type, we must examine the signature
13068 -- of the actual primitive, not that of the generic formal, which for
13069 -- example may be an interface. However the name and initial value
13070 -- of the inherited operation are those of the formal primitive.
13072 Formal := First_Formal (Parent_Subp);
13074 if Present (Actual_Subp) then
13075 Formal_Of_Actual := First_Formal (Actual_Subp);
13077 Formal_Of_Actual := Empty;
13080 while Present (Formal) loop
13081 New_Formal := New_Copy (Formal);
13083 -- Normally we do not go copying parents, but in the case of
13084 -- formals, we need to link up to the declaration (which is the
13085 -- parameter specification), and it is fine to link up to the
13086 -- original formal's parameter specification in this case.
13088 Set_Parent (New_Formal, Parent (Formal));
13089 Append_Entity (New_Formal, New_Subp);
13091 if Present (Formal_Of_Actual) then
13092 Replace_Type (Formal_Of_Actual, New_Formal);
13093 Next_Formal (Formal_Of_Actual);
13095 Replace_Type (Formal, New_Formal);
13098 Next_Formal (Formal);
13101 -- If this derivation corresponds to a tagged generic actual, then
13102 -- primitive operations rename those of the actual. Otherwise the
13103 -- primitive operations rename those of the parent type, If the parent
13104 -- renames an intrinsic operator, so does the new subprogram. We except
13105 -- concatenation, which is always properly typed, and does not get
13106 -- expanded as other intrinsic operations.
13108 if No (Actual_Subp) then
13109 if Is_Intrinsic_Subprogram (Parent_Subp) then
13110 Set_Is_Intrinsic_Subprogram (New_Subp);
13112 if Present (Alias (Parent_Subp))
13113 and then Chars (Parent_Subp) /= Name_Op_Concat
13115 Set_Alias (New_Subp, Alias (Parent_Subp));
13117 Set_Alias (New_Subp, Parent_Subp);
13121 Set_Alias (New_Subp, Parent_Subp);
13125 Set_Alias (New_Subp, Actual_Subp);
13128 -- Derived subprograms of a tagged type must inherit the convention
13129 -- of the parent subprogram (a requirement of AI-117). Derived
13130 -- subprograms of untagged types simply get convention Ada by default.
13132 if Is_Tagged_Type (Derived_Type) then
13133 Set_Convention (New_Subp, Convention (Parent_Subp));
13136 -- Predefined controlled operations retain their name even if the parent
13137 -- is hidden (see above), but they are not primitive operations if the
13138 -- ancestor is not visible, for example if the parent is a private
13139 -- extension completed with a controlled extension. Note that a full
13140 -- type that is controlled can break privacy: the flag Is_Controlled is
13141 -- set on both views of the type.
13143 if Is_Controlled (Parent_Type)
13145 (Chars (Parent_Subp) = Name_Initialize
13146 or else Chars (Parent_Subp) = Name_Adjust
13147 or else Chars (Parent_Subp) = Name_Finalize)
13148 and then Is_Hidden (Parent_Subp)
13149 and then not Is_Visibly_Controlled (Parent_Type)
13151 Set_Is_Hidden (New_Subp);
13154 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13155 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13157 if Ekind (Parent_Subp) = E_Procedure then
13158 Set_Is_Valued_Procedure
13159 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13161 Set_Has_Controlling_Result
13162 (New_Subp, Has_Controlling_Result (Parent_Subp));
13165 -- No_Return must be inherited properly. If this is overridden in the
13166 -- case of a dispatching operation, then a check is made in Sem_Disp
13167 -- that the overriding operation is also No_Return (no such check is
13168 -- required for the case of non-dispatching operation.
13170 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13172 -- A derived function with a controlling result is abstract. If the
13173 -- Derived_Type is a nonabstract formal generic derived type, then
13174 -- inherited operations are not abstract: the required check is done at
13175 -- instantiation time. If the derivation is for a generic actual, the
13176 -- function is not abstract unless the actual is.
13178 if Is_Generic_Type (Derived_Type)
13179 and then not Is_Abstract_Type (Derived_Type)
13183 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13184 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13186 elsif Ada_Version >= Ada_2005
13187 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13188 or else (Is_Tagged_Type (Derived_Type)
13189 and then Etype (New_Subp) = Derived_Type
13190 and then not Is_Null_Extension (Derived_Type))
13191 or else (Is_Tagged_Type (Derived_Type)
13192 and then Ekind (Etype (New_Subp)) =
13193 E_Anonymous_Access_Type
13194 and then Designated_Type (Etype (New_Subp)) =
13196 and then not Is_Null_Extension (Derived_Type)))
13197 and then No (Actual_Subp)
13199 if not Is_Tagged_Type (Derived_Type)
13200 or else Is_Abstract_Type (Derived_Type)
13201 or else Is_Abstract_Subprogram (Alias (New_Subp))
13203 Set_Is_Abstract_Subprogram (New_Subp);
13205 Set_Requires_Overriding (New_Subp);
13208 elsif Ada_Version < Ada_2005
13209 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13210 or else (Is_Tagged_Type (Derived_Type)
13211 and then Etype (New_Subp) = Derived_Type
13212 and then No (Actual_Subp)))
13214 Set_Is_Abstract_Subprogram (New_Subp);
13216 -- AI05-0097 : an inherited operation that dispatches on result is
13217 -- abstract if the derived type is abstract, even if the parent type
13218 -- is concrete and the derived type is a null extension.
13220 elsif Has_Controlling_Result (Alias (New_Subp))
13221 and then Is_Abstract_Type (Etype (New_Subp))
13223 Set_Is_Abstract_Subprogram (New_Subp);
13225 -- Finally, if the parent type is abstract we must verify that all
13226 -- inherited operations are either non-abstract or overridden, or that
13227 -- the derived type itself is abstract (this check is performed at the
13228 -- end of a package declaration, in Check_Abstract_Overriding). A
13229 -- private overriding in the parent type will not be visible in the
13230 -- derivation if we are not in an inner package or in a child unit of
13231 -- the parent type, in which case the abstractness of the inherited
13232 -- operation is carried to the new subprogram.
13234 elsif Is_Abstract_Type (Parent_Type)
13235 and then not In_Open_Scopes (Scope (Parent_Type))
13236 and then Is_Private_Overriding
13237 and then Is_Abstract_Subprogram (Visible_Subp)
13239 if No (Actual_Subp) then
13240 Set_Alias (New_Subp, Visible_Subp);
13241 Set_Is_Abstract_Subprogram (New_Subp, True);
13244 -- If this is a derivation for an instance of a formal derived
13245 -- type, abstractness comes from the primitive operation of the
13246 -- actual, not from the operation inherited from the ancestor.
13248 Set_Is_Abstract_Subprogram
13249 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13253 New_Overloaded_Entity (New_Subp, Derived_Type);
13255 -- Check for case of a derived subprogram for the instantiation of a
13256 -- formal derived tagged type, if so mark the subprogram as dispatching
13257 -- and inherit the dispatching attributes of the parent subprogram. The
13258 -- derived subprogram is effectively renaming of the actual subprogram,
13259 -- so it needs to have the same attributes as the actual.
13261 if Present (Actual_Subp)
13262 and then Is_Dispatching_Operation (Parent_Subp)
13264 Set_Is_Dispatching_Operation (New_Subp);
13266 if Present (DTC_Entity (Parent_Subp)) then
13267 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
13268 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
13272 -- Indicate that a derived subprogram does not require a body and that
13273 -- it does not require processing of default expressions.
13275 Set_Has_Completion (New_Subp);
13276 Set_Default_Expressions_Processed (New_Subp);
13278 if Ekind (New_Subp) = E_Function then
13279 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13281 end Derive_Subprogram;
13283 ------------------------
13284 -- Derive_Subprograms --
13285 ------------------------
13287 procedure Derive_Subprograms
13288 (Parent_Type : Entity_Id;
13289 Derived_Type : Entity_Id;
13290 Generic_Actual : Entity_Id := Empty)
13292 Op_List : constant Elist_Id :=
13293 Collect_Primitive_Operations (Parent_Type);
13295 function Check_Derived_Type return Boolean;
13296 -- Check that all the entities derived from Parent_Type are found in
13297 -- the list of primitives of Derived_Type exactly in the same order.
13299 procedure Derive_Interface_Subprogram
13300 (New_Subp : in out Entity_Id;
13302 Actual_Subp : Entity_Id);
13303 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13304 -- (which is an interface primitive). If Generic_Actual is present then
13305 -- Actual_Subp is the actual subprogram corresponding with the generic
13306 -- subprogram Subp.
13308 function Check_Derived_Type return Boolean is
13312 New_Subp : Entity_Id;
13317 -- Traverse list of entities in the current scope searching for
13318 -- an incomplete type whose full-view is derived type
13320 E := First_Entity (Scope (Derived_Type));
13322 and then E /= Derived_Type
13324 if Ekind (E) = E_Incomplete_Type
13325 and then Present (Full_View (E))
13326 and then Full_View (E) = Derived_Type
13328 -- Disable this test if Derived_Type completes an incomplete
13329 -- type because in such case more primitives can be added
13330 -- later to the list of primitives of Derived_Type by routine
13331 -- Process_Incomplete_Dependents
13336 E := Next_Entity (E);
13339 List := Collect_Primitive_Operations (Derived_Type);
13340 Elmt := First_Elmt (List);
13342 Op_Elmt := First_Elmt (Op_List);
13343 while Present (Op_Elmt) loop
13344 Subp := Node (Op_Elmt);
13345 New_Subp := Node (Elmt);
13347 -- At this early stage Derived_Type has no entities with attribute
13348 -- Interface_Alias. In addition, such primitives are always
13349 -- located at the end of the list of primitives of Parent_Type.
13350 -- Therefore, if found we can safely stop processing pending
13353 exit when Present (Interface_Alias (Subp));
13355 -- Handle hidden entities
13357 if not Is_Predefined_Dispatching_Operation (Subp)
13358 and then Is_Hidden (Subp)
13360 if Present (New_Subp)
13361 and then Primitive_Names_Match (Subp, New_Subp)
13367 if not Present (New_Subp)
13368 or else Ekind (Subp) /= Ekind (New_Subp)
13369 or else not Primitive_Names_Match (Subp, New_Subp)
13377 Next_Elmt (Op_Elmt);
13381 end Check_Derived_Type;
13383 ---------------------------------
13384 -- Derive_Interface_Subprogram --
13385 ---------------------------------
13387 procedure Derive_Interface_Subprogram
13388 (New_Subp : in out Entity_Id;
13390 Actual_Subp : Entity_Id)
13392 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13393 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13396 pragma Assert (Is_Interface (Iface_Type));
13399 (New_Subp => New_Subp,
13400 Parent_Subp => Iface_Subp,
13401 Derived_Type => Derived_Type,
13402 Parent_Type => Iface_Type,
13403 Actual_Subp => Actual_Subp);
13405 -- Given that this new interface entity corresponds with a primitive
13406 -- of the parent that was not overridden we must leave it associated
13407 -- with its parent primitive to ensure that it will share the same
13408 -- dispatch table slot when overridden.
13410 if No (Actual_Subp) then
13411 Set_Alias (New_Subp, Subp);
13413 -- For instantiations this is not needed since the previous call to
13414 -- Derive_Subprogram leaves the entity well decorated.
13417 pragma Assert (Alias (New_Subp) = Actual_Subp);
13420 end Derive_Interface_Subprogram;
13424 Alias_Subp : Entity_Id;
13425 Act_List : Elist_Id;
13426 Act_Elmt : Elmt_Id := No_Elmt;
13427 Act_Subp : Entity_Id := Empty;
13429 Need_Search : Boolean := False;
13430 New_Subp : Entity_Id := Empty;
13431 Parent_Base : Entity_Id;
13434 -- Start of processing for Derive_Subprograms
13437 if Ekind (Parent_Type) = E_Record_Type_With_Private
13438 and then Has_Discriminants (Parent_Type)
13439 and then Present (Full_View (Parent_Type))
13441 Parent_Base := Full_View (Parent_Type);
13443 Parent_Base := Parent_Type;
13446 if Present (Generic_Actual) then
13447 Act_List := Collect_Primitive_Operations (Generic_Actual);
13448 Act_Elmt := First_Elmt (Act_List);
13451 -- Derive primitives inherited from the parent. Note that if the generic
13452 -- actual is present, this is not really a type derivation, it is a
13453 -- completion within an instance.
13455 -- Case 1: Derived_Type does not implement interfaces
13457 if not Is_Tagged_Type (Derived_Type)
13458 or else (not Has_Interfaces (Derived_Type)
13459 and then not (Present (Generic_Actual)
13461 Has_Interfaces (Generic_Actual)))
13463 Elmt := First_Elmt (Op_List);
13464 while Present (Elmt) loop
13465 Subp := Node (Elmt);
13467 -- Literals are derived earlier in the process of building the
13468 -- derived type, and are skipped here.
13470 if Ekind (Subp) = E_Enumeration_Literal then
13473 -- The actual is a direct descendant and the common primitive
13474 -- operations appear in the same order.
13476 -- If the generic parent type is present, the derived type is an
13477 -- instance of a formal derived type, and within the instance its
13478 -- operations are those of the actual. We derive from the formal
13479 -- type but make the inherited operations aliases of the
13480 -- corresponding operations of the actual.
13483 pragma Assert (No (Node (Act_Elmt))
13484 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13486 Type_Conformant (Subp, Node (Act_Elmt),
13487 Skip_Controlling_Formals => True)));
13490 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13492 if Present (Act_Elmt) then
13493 Next_Elmt (Act_Elmt);
13500 -- Case 2: Derived_Type implements interfaces
13503 -- If the parent type has no predefined primitives we remove
13504 -- predefined primitives from the list of primitives of generic
13505 -- actual to simplify the complexity of this algorithm.
13507 if Present (Generic_Actual) then
13509 Has_Predefined_Primitives : Boolean := False;
13512 -- Check if the parent type has predefined primitives
13514 Elmt := First_Elmt (Op_List);
13515 while Present (Elmt) loop
13516 Subp := Node (Elmt);
13518 if Is_Predefined_Dispatching_Operation (Subp)
13519 and then not Comes_From_Source (Ultimate_Alias (Subp))
13521 Has_Predefined_Primitives := True;
13528 -- Remove predefined primitives of Generic_Actual. We must use
13529 -- an auxiliary list because in case of tagged types the value
13530 -- returned by Collect_Primitive_Operations is the value stored
13531 -- in its Primitive_Operations attribute (and we don't want to
13532 -- modify its current contents).
13534 if not Has_Predefined_Primitives then
13536 Aux_List : constant Elist_Id := New_Elmt_List;
13539 Elmt := First_Elmt (Act_List);
13540 while Present (Elmt) loop
13541 Subp := Node (Elmt);
13543 if not Is_Predefined_Dispatching_Operation (Subp)
13544 or else Comes_From_Source (Subp)
13546 Append_Elmt (Subp, Aux_List);
13552 Act_List := Aux_List;
13556 Act_Elmt := First_Elmt (Act_List);
13557 Act_Subp := Node (Act_Elmt);
13561 -- Stage 1: If the generic actual is not present we derive the
13562 -- primitives inherited from the parent type. If the generic parent
13563 -- type is present, the derived type is an instance of a formal
13564 -- derived type, and within the instance its operations are those of
13565 -- the actual. We derive from the formal type but make the inherited
13566 -- operations aliases of the corresponding operations of the actual.
13568 Elmt := First_Elmt (Op_List);
13569 while Present (Elmt) loop
13570 Subp := Node (Elmt);
13571 Alias_Subp := Ultimate_Alias (Subp);
13573 -- Do not derive internal entities of the parent that link
13574 -- interface primitives with their covering primitive. These
13575 -- entities will be added to this type when frozen.
13577 if Present (Interface_Alias (Subp)) then
13581 -- If the generic actual is present find the corresponding
13582 -- operation in the generic actual. If the parent type is a
13583 -- direct ancestor of the derived type then, even if it is an
13584 -- interface, the operations are inherited from the primary
13585 -- dispatch table and are in the proper order. If we detect here
13586 -- that primitives are not in the same order we traverse the list
13587 -- of primitive operations of the actual to find the one that
13588 -- implements the interface primitive.
13592 (Present (Generic_Actual)
13593 and then Present (Act_Subp)
13595 (Primitive_Names_Match (Subp, Act_Subp)
13597 Type_Conformant (Subp, Act_Subp,
13598 Skip_Controlling_Formals => True)))
13600 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
13602 -- Remember that we need searching for all pending primitives
13604 Need_Search := True;
13606 -- Handle entities associated with interface primitives
13608 if Present (Alias_Subp)
13609 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13610 and then not Is_Predefined_Dispatching_Operation (Subp)
13612 -- Search for the primitive in the homonym chain
13615 Find_Primitive_Covering_Interface
13616 (Tagged_Type => Generic_Actual,
13617 Iface_Prim => Alias_Subp);
13619 -- Previous search may not locate primitives covering
13620 -- interfaces defined in generics units or instantiations.
13621 -- (it fails if the covering primitive has formals whose
13622 -- type is also defined in generics or instantiations).
13623 -- In such case we search in the list of primitives of the
13624 -- generic actual for the internal entity that links the
13625 -- interface primitive and the covering primitive.
13628 and then Is_Generic_Type (Parent_Type)
13630 -- This code has been designed to handle only generic
13631 -- formals that implement interfaces that are defined
13632 -- in a generic unit or instantiation. If this code is
13633 -- needed for other cases we must review it because
13634 -- (given that it relies on Original_Location to locate
13635 -- the primitive of Generic_Actual that covers the
13636 -- interface) it could leave linked through attribute
13637 -- Alias entities of unrelated instantiations).
13641 (Scope (Find_Dispatching_Type (Alias_Subp)))
13643 Instantiation_Depth
13644 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13647 Iface_Prim_Loc : constant Source_Ptr :=
13648 Original_Location (Sloc (Alias_Subp));
13653 First_Elmt (Primitive_Operations (Generic_Actual));
13655 Search : while Present (Elmt) loop
13656 Prim := Node (Elmt);
13658 if Present (Interface_Alias (Prim))
13659 and then Original_Location
13660 (Sloc (Interface_Alias (Prim)))
13663 Act_Subp := Alias (Prim);
13672 pragma Assert (Present (Act_Subp)
13673 or else Is_Abstract_Type (Generic_Actual)
13674 or else Serious_Errors_Detected > 0);
13676 -- Handle predefined primitives plus the rest of user-defined
13680 Act_Elmt := First_Elmt (Act_List);
13681 while Present (Act_Elmt) loop
13682 Act_Subp := Node (Act_Elmt);
13684 exit when Primitive_Names_Match (Subp, Act_Subp)
13685 and then Type_Conformant
13687 Skip_Controlling_Formals => True)
13688 and then No (Interface_Alias (Act_Subp));
13690 Next_Elmt (Act_Elmt);
13693 if No (Act_Elmt) then
13699 -- Case 1: If the parent is a limited interface then it has the
13700 -- predefined primitives of synchronized interfaces. However, the
13701 -- actual type may be a non-limited type and hence it does not
13702 -- have such primitives.
13704 if Present (Generic_Actual)
13705 and then not Present (Act_Subp)
13706 and then Is_Limited_Interface (Parent_Base)
13707 and then Is_Predefined_Interface_Primitive (Subp)
13711 -- Case 2: Inherit entities associated with interfaces that were
13712 -- not covered by the parent type. We exclude here null interface
13713 -- primitives because they do not need special management.
13715 -- We also exclude interface operations that are renamings. If the
13716 -- subprogram is an explicit renaming of an interface primitive,
13717 -- it is a regular primitive operation, and the presence of its
13718 -- alias is not relevant: it has to be derived like any other
13721 elsif Present (Alias (Subp))
13722 and then Nkind (Unit_Declaration_Node (Subp)) /=
13723 N_Subprogram_Renaming_Declaration
13724 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13726 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13727 and then Null_Present (Parent (Alias_Subp)))
13729 -- If this is an abstract private type then we transfer the
13730 -- derivation of the interface primitive from the partial view
13731 -- to the full view. This is safe because all the interfaces
13732 -- must be visible in the partial view. Done to avoid adding
13733 -- a new interface derivation to the private part of the
13734 -- enclosing package; otherwise this new derivation would be
13735 -- decorated as hidden when the analysis of the enclosing
13736 -- package completes.
13738 if Is_Abstract_Type (Derived_Type)
13739 and then In_Private_Part (Current_Scope)
13740 and then Has_Private_Declaration (Derived_Type)
13743 Partial_View : Entity_Id;
13748 Partial_View := First_Entity (Current_Scope);
13750 exit when No (Partial_View)
13751 or else (Has_Private_Declaration (Partial_View)
13753 Full_View (Partial_View) = Derived_Type);
13755 Next_Entity (Partial_View);
13758 -- If the partial view was not found then the source code
13759 -- has errors and the derivation is not needed.
13761 if Present (Partial_View) then
13763 First_Elmt (Primitive_Operations (Partial_View));
13764 while Present (Elmt) loop
13765 Ent := Node (Elmt);
13767 if Present (Alias (Ent))
13768 and then Ultimate_Alias (Ent) = Alias (Subp)
13771 (Ent, Primitive_Operations (Derived_Type));
13778 -- If the interface primitive was not found in the
13779 -- partial view then this interface primitive was
13780 -- overridden. We add a derivation to activate in
13781 -- Derive_Progenitor_Subprograms the machinery to
13785 Derive_Interface_Subprogram
13786 (New_Subp => New_Subp,
13788 Actual_Subp => Act_Subp);
13793 Derive_Interface_Subprogram
13794 (New_Subp => New_Subp,
13796 Actual_Subp => Act_Subp);
13799 -- Case 3: Common derivation
13803 (New_Subp => New_Subp,
13804 Parent_Subp => Subp,
13805 Derived_Type => Derived_Type,
13806 Parent_Type => Parent_Base,
13807 Actual_Subp => Act_Subp);
13810 -- No need to update Act_Elm if we must search for the
13811 -- corresponding operation in the generic actual
13814 and then Present (Act_Elmt)
13816 Next_Elmt (Act_Elmt);
13817 Act_Subp := Node (Act_Elmt);
13824 -- Inherit additional operations from progenitors. If the derived
13825 -- type is a generic actual, there are not new primitive operations
13826 -- for the type because it has those of the actual, and therefore
13827 -- nothing needs to be done. The renamings generated above are not
13828 -- primitive operations, and their purpose is simply to make the
13829 -- proper operations visible within an instantiation.
13831 if No (Generic_Actual) then
13832 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13836 -- Final check: Direct descendants must have their primitives in the
13837 -- same order. We exclude from this test untagged types and instances
13838 -- of formal derived types. We skip this test if we have already
13839 -- reported serious errors in the sources.
13841 pragma Assert (not Is_Tagged_Type (Derived_Type)
13842 or else Present (Generic_Actual)
13843 or else Serious_Errors_Detected > 0
13844 or else Check_Derived_Type);
13845 end Derive_Subprograms;
13847 --------------------------------
13848 -- Derived_Standard_Character --
13849 --------------------------------
13851 procedure Derived_Standard_Character
13853 Parent_Type : Entity_Id;
13854 Derived_Type : Entity_Id)
13856 Loc : constant Source_Ptr := Sloc (N);
13857 Def : constant Node_Id := Type_Definition (N);
13858 Indic : constant Node_Id := Subtype_Indication (Def);
13859 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13860 Implicit_Base : constant Entity_Id :=
13862 (E_Enumeration_Type, N, Derived_Type, 'B');
13868 Discard_Node (Process_Subtype (Indic, N));
13870 Set_Etype (Implicit_Base, Parent_Base);
13871 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
13872 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
13874 Set_Is_Character_Type (Implicit_Base, True);
13875 Set_Has_Delayed_Freeze (Implicit_Base);
13877 -- The bounds of the implicit base are the bounds of the parent base.
13878 -- Note that their type is the parent base.
13880 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13881 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13883 Set_Scalar_Range (Implicit_Base,
13886 High_Bound => Hi));
13888 Conditional_Delay (Derived_Type, Parent_Type);
13890 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13891 Set_Etype (Derived_Type, Implicit_Base);
13892 Set_Size_Info (Derived_Type, Parent_Type);
13894 if Unknown_RM_Size (Derived_Type) then
13895 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13898 Set_Is_Character_Type (Derived_Type, True);
13900 if Nkind (Indic) /= N_Subtype_Indication then
13902 -- If no explicit constraint, the bounds are those
13903 -- of the parent type.
13905 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13906 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13907 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13910 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13912 -- Because the implicit base is used in the conversion of the bounds, we
13913 -- have to freeze it now. This is similar to what is done for numeric
13914 -- types, and it equally suspicious, but otherwise a non-static bound
13915 -- will have a reference to an unfrozen type, which is rejected by Gigi
13916 -- (???). This requires specific care for definition of stream
13917 -- attributes. For details, see comments at the end of
13918 -- Build_Derived_Numeric_Type.
13920 Freeze_Before (N, Implicit_Base);
13921 end Derived_Standard_Character;
13923 ------------------------------
13924 -- Derived_Type_Declaration --
13925 ------------------------------
13927 procedure Derived_Type_Declaration
13930 Is_Completion : Boolean)
13932 Parent_Type : Entity_Id;
13934 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13935 -- Check whether the parent type is a generic formal, or derives
13936 -- directly or indirectly from one.
13938 ------------------------
13939 -- Comes_From_Generic --
13940 ------------------------
13942 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13944 if Is_Generic_Type (Typ) then
13947 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13950 elsif Is_Private_Type (Typ)
13951 and then Present (Full_View (Typ))
13952 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
13956 elsif Is_Generic_Actual_Type (Typ) then
13962 end Comes_From_Generic;
13966 Def : constant Node_Id := Type_Definition (N);
13967 Iface_Def : Node_Id;
13968 Indic : constant Node_Id := Subtype_Indication (Def);
13969 Extension : constant Node_Id := Record_Extension_Part (Def);
13970 Parent_Node : Node_Id;
13973 -- Start of processing for Derived_Type_Declaration
13976 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
13978 -- Ada 2005 (AI-251): In case of interface derivation check that the
13979 -- parent is also an interface.
13981 if Interface_Present (Def) then
13982 Check_SPARK_Restriction ("interface is not allowed", Def);
13984 if not Is_Interface (Parent_Type) then
13985 Diagnose_Interface (Indic, Parent_Type);
13988 Parent_Node := Parent (Base_Type (Parent_Type));
13989 Iface_Def := Type_Definition (Parent_Node);
13991 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
13992 -- other limited interfaces.
13994 if Limited_Present (Def) then
13995 if Limited_Present (Iface_Def) then
13998 elsif Protected_Present (Iface_Def) then
14000 ("descendant of& must be declared"
14001 & " as a protected interface",
14004 elsif Synchronized_Present (Iface_Def) then
14006 ("descendant of& must be declared"
14007 & " as a synchronized interface",
14010 elsif Task_Present (Iface_Def) then
14012 ("descendant of& must be declared as a task interface",
14017 ("(Ada 2005) limited interface cannot "
14018 & "inherit from non-limited interface", Indic);
14021 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14022 -- from non-limited or limited interfaces.
14024 elsif not Protected_Present (Def)
14025 and then not Synchronized_Present (Def)
14026 and then not Task_Present (Def)
14028 if Limited_Present (Iface_Def) then
14031 elsif Protected_Present (Iface_Def) then
14033 ("descendant of& must be declared"
14034 & " as a protected interface",
14037 elsif Synchronized_Present (Iface_Def) then
14039 ("descendant of& must be declared"
14040 & " as a synchronized interface",
14043 elsif Task_Present (Iface_Def) then
14045 ("descendant of& must be declared as a task interface",
14054 if Is_Tagged_Type (Parent_Type)
14055 and then Is_Concurrent_Type (Parent_Type)
14056 and then not Is_Interface (Parent_Type)
14059 ("parent type of a record extension cannot be "
14060 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14061 Set_Etype (T, Any_Type);
14065 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14068 if Is_Tagged_Type (Parent_Type)
14069 and then Is_Non_Empty_List (Interface_List (Def))
14076 Intf := First (Interface_List (Def));
14077 while Present (Intf) loop
14078 T := Find_Type_Of_Subtype_Indic (Intf);
14080 if not Is_Interface (T) then
14081 Diagnose_Interface (Intf, T);
14083 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14084 -- a limited type from having a nonlimited progenitor.
14086 elsif (Limited_Present (Def)
14087 or else (not Is_Interface (Parent_Type)
14088 and then Is_Limited_Type (Parent_Type)))
14089 and then not Is_Limited_Interface (T)
14092 ("progenitor interface& of limited type must be limited",
14101 if Parent_Type = Any_Type
14102 or else Etype (Parent_Type) = Any_Type
14103 or else (Is_Class_Wide_Type (Parent_Type)
14104 and then Etype (Parent_Type) = T)
14106 -- If Parent_Type is undefined or illegal, make new type into a
14107 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14108 -- errors. If this is a self-definition, emit error now.
14111 or else T = Etype (Parent_Type)
14113 Error_Msg_N ("type cannot be used in its own definition", Indic);
14116 Set_Ekind (T, Ekind (Parent_Type));
14117 Set_Etype (T, Any_Type);
14118 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14120 if Is_Tagged_Type (T)
14121 and then Is_Record_Type (T)
14123 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14129 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14130 -- an interface is special because the list of interfaces in the full
14131 -- view can be given in any order. For example:
14133 -- type A is interface;
14134 -- type B is interface and A;
14135 -- type D is new B with private;
14137 -- type D is new A and B with null record; -- 1 --
14139 -- In this case we perform the following transformation of -1-:
14141 -- type D is new B and A with null record;
14143 -- If the parent of the full-view covers the parent of the partial-view
14144 -- we have two possible cases:
14146 -- 1) They have the same parent
14147 -- 2) The parent of the full-view implements some further interfaces
14149 -- In both cases we do not need to perform the transformation. In the
14150 -- first case the source program is correct and the transformation is
14151 -- not needed; in the second case the source program does not fulfill
14152 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14155 -- This transformation not only simplifies the rest of the analysis of
14156 -- this type declaration but also simplifies the correct generation of
14157 -- the object layout to the expander.
14159 if In_Private_Part (Current_Scope)
14160 and then Is_Interface (Parent_Type)
14164 Partial_View : Entity_Id;
14165 Partial_View_Parent : Entity_Id;
14166 New_Iface : Node_Id;
14169 -- Look for the associated private type declaration
14171 Partial_View := First_Entity (Current_Scope);
14173 exit when No (Partial_View)
14174 or else (Has_Private_Declaration (Partial_View)
14175 and then Full_View (Partial_View) = T);
14177 Next_Entity (Partial_View);
14180 -- If the partial view was not found then the source code has
14181 -- errors and the transformation is not needed.
14183 if Present (Partial_View) then
14184 Partial_View_Parent := Etype (Partial_View);
14186 -- If the parent of the full-view covers the parent of the
14187 -- partial-view we have nothing else to do.
14189 if Interface_Present_In_Ancestor
14190 (Parent_Type, Partial_View_Parent)
14194 -- Traverse the list of interfaces of the full-view to look
14195 -- for the parent of the partial-view and perform the tree
14199 Iface := First (Interface_List (Def));
14200 while Present (Iface) loop
14201 if Etype (Iface) = Etype (Partial_View) then
14202 Rewrite (Subtype_Indication (Def),
14203 New_Copy (Subtype_Indication
14204 (Parent (Partial_View))));
14207 Make_Identifier (Sloc (N), Chars (Parent_Type));
14208 Append (New_Iface, Interface_List (Def));
14210 -- Analyze the transformed code
14212 Derived_Type_Declaration (T, N, Is_Completion);
14223 -- Only composite types other than array types are allowed to have
14224 -- discriminants. In SPARK, no types are allowed to have discriminants.
14226 if Present (Discriminant_Specifications (N)) then
14227 if (Is_Elementary_Type (Parent_Type)
14228 or else Is_Array_Type (Parent_Type))
14229 and then not Error_Posted (N)
14232 ("elementary or array type cannot have discriminants",
14233 Defining_Identifier (First (Discriminant_Specifications (N))));
14234 Set_Has_Discriminants (T, False);
14236 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14240 -- In Ada 83, a derived type defined in a package specification cannot
14241 -- be used for further derivation until the end of its visible part.
14242 -- Note that derivation in the private part of the package is allowed.
14244 if Ada_Version = Ada_83
14245 and then Is_Derived_Type (Parent_Type)
14246 and then In_Visible_Part (Scope (Parent_Type))
14248 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14250 ("(Ada 83): premature use of type for derivation", Indic);
14254 -- Check for early use of incomplete or private type
14256 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14257 Error_Msg_N ("premature derivation of incomplete type", Indic);
14260 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14261 and then not Comes_From_Generic (Parent_Type))
14262 or else Has_Private_Component (Parent_Type)
14264 -- The ancestor type of a formal type can be incomplete, in which
14265 -- case only the operations of the partial view are available in the
14266 -- generic. Subsequent checks may be required when the full view is
14267 -- analyzed to verify that a derivation from a tagged type has an
14270 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14273 elsif No (Underlying_Type (Parent_Type))
14274 or else Has_Private_Component (Parent_Type)
14277 ("premature derivation of derived or private type", Indic);
14279 -- Flag the type itself as being in error, this prevents some
14280 -- nasty problems with subsequent uses of the malformed type.
14282 Set_Error_Posted (T);
14284 -- Check that within the immediate scope of an untagged partial
14285 -- view it's illegal to derive from the partial view if the
14286 -- full view is tagged. (7.3(7))
14288 -- We verify that the Parent_Type is a partial view by checking
14289 -- that it is not a Full_Type_Declaration (i.e. a private type or
14290 -- private extension declaration), to distinguish a partial view
14291 -- from a derivation from a private type which also appears as
14292 -- E_Private_Type. If the parent base type is not declared in an
14293 -- enclosing scope there is no need to check.
14295 elsif Present (Full_View (Parent_Type))
14296 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14297 and then not Is_Tagged_Type (Parent_Type)
14298 and then Is_Tagged_Type (Full_View (Parent_Type))
14299 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14302 ("premature derivation from type with tagged full view",
14307 -- Check that form of derivation is appropriate
14309 Taggd := Is_Tagged_Type (Parent_Type);
14311 -- Perhaps the parent type should be changed to the class-wide type's
14312 -- specific type in this case to prevent cascading errors ???
14314 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14315 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14319 if Present (Extension) and then not Taggd then
14321 ("type derived from untagged type cannot have extension", Indic);
14323 elsif No (Extension) and then Taggd then
14325 -- If this declaration is within a private part (or body) of a
14326 -- generic instantiation then the derivation is allowed (the parent
14327 -- type can only appear tagged in this case if it's a generic actual
14328 -- type, since it would otherwise have been rejected in the analysis
14329 -- of the generic template).
14331 if not Is_Generic_Actual_Type (Parent_Type)
14332 or else In_Visible_Part (Scope (Parent_Type))
14334 if Is_Class_Wide_Type (Parent_Type) then
14336 ("parent type must not be a class-wide type", Indic);
14338 -- Use specific type to prevent cascaded errors.
14340 Parent_Type := Etype (Parent_Type);
14344 ("type derived from tagged type must have extension", Indic);
14349 -- AI-443: Synchronized formal derived types require a private
14350 -- extension. There is no point in checking the ancestor type or
14351 -- the progenitors since the construct is wrong to begin with.
14353 if Ada_Version >= Ada_2005
14354 and then Is_Generic_Type (T)
14355 and then Present (Original_Node (N))
14358 Decl : constant Node_Id := Original_Node (N);
14361 if Nkind (Decl) = N_Formal_Type_Declaration
14362 and then Nkind (Formal_Type_Definition (Decl)) =
14363 N_Formal_Derived_Type_Definition
14364 and then Synchronized_Present (Formal_Type_Definition (Decl))
14365 and then No (Extension)
14367 -- Avoid emitting a duplicate error message
14369 and then not Error_Posted (Indic)
14372 ("synchronized derived type must have extension", N);
14377 if Null_Exclusion_Present (Def)
14378 and then not Is_Access_Type (Parent_Type)
14380 Error_Msg_N ("null exclusion can only apply to an access type", N);
14383 -- Avoid deriving parent primitives of underlying record views
14385 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14386 Derive_Subps => not Is_Underlying_Record_View (T));
14388 -- AI-419: The parent type of an explicitly limited derived type must
14389 -- be a limited type or a limited interface.
14391 if Limited_Present (Def) then
14392 Set_Is_Limited_Record (T);
14394 if Is_Interface (T) then
14395 Set_Is_Limited_Interface (T);
14398 if not Is_Limited_Type (Parent_Type)
14400 (not Is_Interface (Parent_Type)
14401 or else not Is_Limited_Interface (Parent_Type))
14403 -- AI05-0096: a derivation in the private part of an instance is
14404 -- legal if the generic formal is untagged limited, and the actual
14407 if Is_Generic_Actual_Type (Parent_Type)
14408 and then In_Private_Part (Current_Scope)
14411 (Generic_Parent_Type (Parent (Parent_Type)))
14417 ("parent type& of limited type must be limited",
14423 -- In SPARK, there are no derived type definitions other than type
14424 -- extensions of tagged record types.
14426 if No (Extension) then
14427 Check_SPARK_Restriction ("derived type is not allowed", N);
14429 end Derived_Type_Declaration;
14431 ------------------------
14432 -- Diagnose_Interface --
14433 ------------------------
14435 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14437 if not Is_Interface (E)
14438 and then E /= Any_Type
14440 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14442 end Diagnose_Interface;
14444 ----------------------------------
14445 -- Enumeration_Type_Declaration --
14446 ----------------------------------
14448 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14455 -- Create identifier node representing lower bound
14457 B_Node := New_Node (N_Identifier, Sloc (Def));
14458 L := First (Literals (Def));
14459 Set_Chars (B_Node, Chars (L));
14460 Set_Entity (B_Node, L);
14461 Set_Etype (B_Node, T);
14462 Set_Is_Static_Expression (B_Node, True);
14464 R_Node := New_Node (N_Range, Sloc (Def));
14465 Set_Low_Bound (R_Node, B_Node);
14467 Set_Ekind (T, E_Enumeration_Type);
14468 Set_First_Literal (T, L);
14470 Set_Is_Constrained (T);
14474 -- Loop through literals of enumeration type setting pos and rep values
14475 -- except that if the Ekind is already set, then it means the literal
14476 -- was already constructed (case of a derived type declaration and we
14477 -- should not disturb the Pos and Rep values.
14479 while Present (L) loop
14480 if Ekind (L) /= E_Enumeration_Literal then
14481 Set_Ekind (L, E_Enumeration_Literal);
14482 Set_Enumeration_Pos (L, Ev);
14483 Set_Enumeration_Rep (L, Ev);
14484 Set_Is_Known_Valid (L, True);
14488 New_Overloaded_Entity (L);
14489 Generate_Definition (L);
14490 Set_Convention (L, Convention_Intrinsic);
14492 -- Case of character literal
14494 if Nkind (L) = N_Defining_Character_Literal then
14495 Set_Is_Character_Type (T, True);
14497 -- Check violation of No_Wide_Characters
14499 if Restriction_Check_Required (No_Wide_Characters) then
14500 Get_Name_String (Chars (L));
14502 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14503 Check_Restriction (No_Wide_Characters, L);
14512 -- Now create a node representing upper bound
14514 B_Node := New_Node (N_Identifier, Sloc (Def));
14515 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14516 Set_Entity (B_Node, Last (Literals (Def)));
14517 Set_Etype (B_Node, T);
14518 Set_Is_Static_Expression (B_Node, True);
14520 Set_High_Bound (R_Node, B_Node);
14522 -- Initialize various fields of the type. Some of this information
14523 -- may be overwritten later through rep.clauses.
14525 Set_Scalar_Range (T, R_Node);
14526 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14527 Set_Enum_Esize (T);
14528 Set_Enum_Pos_To_Rep (T, Empty);
14530 -- Enumeration type is in ALFA only if it is not a character type
14532 if not Is_Character_Type (T) then
14533 Set_Is_In_ALFA (T);
14536 -- Set Discard_Names if configuration pragma set, or if there is
14537 -- a parameterless pragma in the current declarative region
14539 if Global_Discard_Names
14540 or else Discard_Names (Scope (T))
14542 Set_Discard_Names (T);
14545 -- Process end label if there is one
14547 if Present (Def) then
14548 Process_End_Label (Def, 'e', T);
14550 end Enumeration_Type_Declaration;
14552 ---------------------------------
14553 -- Expand_To_Stored_Constraint --
14554 ---------------------------------
14556 function Expand_To_Stored_Constraint
14558 Constraint : Elist_Id) return Elist_Id
14560 Explicitly_Discriminated_Type : Entity_Id;
14561 Expansion : Elist_Id;
14562 Discriminant : Entity_Id;
14564 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14565 -- Find the nearest type that actually specifies discriminants
14567 ---------------------------------
14568 -- Type_With_Explicit_Discrims --
14569 ---------------------------------
14571 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14572 Typ : constant E := Base_Type (Id);
14575 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14576 if Present (Full_View (Typ)) then
14577 return Type_With_Explicit_Discrims (Full_View (Typ));
14581 if Has_Discriminants (Typ) then
14586 if Etype (Typ) = Typ then
14588 elsif Has_Discriminants (Typ) then
14591 return Type_With_Explicit_Discrims (Etype (Typ));
14594 end Type_With_Explicit_Discrims;
14596 -- Start of processing for Expand_To_Stored_Constraint
14600 or else Is_Empty_Elmt_List (Constraint)
14605 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14607 if No (Explicitly_Discriminated_Type) then
14611 Expansion := New_Elmt_List;
14614 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14615 while Present (Discriminant) loop
14617 Get_Discriminant_Value (
14618 Discriminant, Explicitly_Discriminated_Type, Constraint),
14620 Next_Stored_Discriminant (Discriminant);
14624 end Expand_To_Stored_Constraint;
14626 ---------------------------
14627 -- Find_Hidden_Interface --
14628 ---------------------------
14630 function Find_Hidden_Interface
14632 Dest : Elist_Id) return Entity_Id
14635 Iface_Elmt : Elmt_Id;
14638 if Present (Src) and then Present (Dest) then
14639 Iface_Elmt := First_Elmt (Src);
14640 while Present (Iface_Elmt) loop
14641 Iface := Node (Iface_Elmt);
14643 if Is_Interface (Iface)
14644 and then not Contain_Interface (Iface, Dest)
14649 Next_Elmt (Iface_Elmt);
14654 end Find_Hidden_Interface;
14656 --------------------
14657 -- Find_Type_Name --
14658 --------------------
14660 function Find_Type_Name (N : Node_Id) return Entity_Id is
14661 Id : constant Entity_Id := Defining_Identifier (N);
14663 New_Id : Entity_Id;
14664 Prev_Par : Node_Id;
14666 procedure Tag_Mismatch;
14667 -- Diagnose a tagged partial view whose full view is untagged.
14668 -- We post the message on the full view, with a reference to
14669 -- the previous partial view. The partial view can be private
14670 -- or incomplete, and these are handled in a different manner,
14671 -- so we determine the position of the error message from the
14672 -- respective slocs of both.
14678 procedure Tag_Mismatch is
14680 if Sloc (Prev) < Sloc (Id) then
14681 if Ada_Version >= Ada_2012
14682 and then Nkind (N) = N_Private_Type_Declaration
14685 ("declaration of private } must be a tagged type ", Id, Prev);
14688 ("full declaration of } must be a tagged type ", Id, Prev);
14691 if Ada_Version >= Ada_2012
14692 and then Nkind (N) = N_Private_Type_Declaration
14695 ("declaration of private } must be a tagged type ", Prev, Id);
14698 ("full declaration of } must be a tagged type ", Prev, Id);
14703 -- Start of processing for Find_Type_Name
14706 -- Find incomplete declaration, if one was given
14708 Prev := Current_Entity_In_Scope (Id);
14710 -- New type declaration
14716 -- Previous declaration exists
14719 Prev_Par := Parent (Prev);
14721 -- Error if not incomplete/private case except if previous
14722 -- declaration is implicit, etc. Enter_Name will emit error if
14725 if not Is_Incomplete_Or_Private_Type (Prev) then
14729 -- Check invalid completion of private or incomplete type
14731 elsif not Nkind_In (N, N_Full_Type_Declaration,
14732 N_Task_Type_Declaration,
14733 N_Protected_Type_Declaration)
14735 (Ada_Version < Ada_2012
14736 or else not Is_Incomplete_Type (Prev)
14737 or else not Nkind_In (N, N_Private_Type_Declaration,
14738 N_Private_Extension_Declaration))
14740 -- Completion must be a full type declarations (RM 7.3(4))
14742 Error_Msg_Sloc := Sloc (Prev);
14743 Error_Msg_NE ("invalid completion of }", Id, Prev);
14745 -- Set scope of Id to avoid cascaded errors. Entity is never
14746 -- examined again, except when saving globals in generics.
14748 Set_Scope (Id, Current_Scope);
14751 -- If this is a repeated incomplete declaration, no further
14752 -- checks are possible.
14754 if Nkind (N) = N_Incomplete_Type_Declaration then
14758 -- Case of full declaration of incomplete type
14760 elsif Ekind (Prev) = E_Incomplete_Type
14761 and then (Ada_Version < Ada_2012
14762 or else No (Full_View (Prev))
14763 or else not Is_Private_Type (Full_View (Prev)))
14766 -- Indicate that the incomplete declaration has a matching full
14767 -- declaration. The defining occurrence of the incomplete
14768 -- declaration remains the visible one, and the procedure
14769 -- Get_Full_View dereferences it whenever the type is used.
14771 if Present (Full_View (Prev)) then
14772 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14775 Set_Full_View (Prev, Id);
14776 Append_Entity (Id, Current_Scope);
14777 Set_Is_Public (Id, Is_Public (Prev));
14778 Set_Is_Internal (Id);
14781 -- If the incomplete view is tagged, a class_wide type has been
14782 -- created already. Use it for the private type as well, in order
14783 -- to prevent multiple incompatible class-wide types that may be
14784 -- created for self-referential anonymous access components.
14786 if Is_Tagged_Type (Prev)
14787 and then Present (Class_Wide_Type (Prev))
14789 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14790 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14791 Set_Etype (Class_Wide_Type (Id), Id);
14794 -- Case of full declaration of private type
14797 -- If the private type was a completion of an incomplete type then
14798 -- update Prev to reference the private type
14800 if Ada_Version >= Ada_2012
14801 and then Ekind (Prev) = E_Incomplete_Type
14802 and then Present (Full_View (Prev))
14803 and then Is_Private_Type (Full_View (Prev))
14805 Prev := Full_View (Prev);
14806 Prev_Par := Parent (Prev);
14809 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14810 if Etype (Prev) /= Prev then
14812 -- Prev is a private subtype or a derived type, and needs
14815 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14818 elsif Ekind (Prev) = E_Private_Type
14819 and then Nkind_In (N, N_Task_Type_Declaration,
14820 N_Protected_Type_Declaration)
14823 ("completion of nonlimited type cannot be limited", N);
14825 elsif Ekind (Prev) = E_Record_Type_With_Private
14826 and then Nkind_In (N, N_Task_Type_Declaration,
14827 N_Protected_Type_Declaration)
14829 if not Is_Limited_Record (Prev) then
14831 ("completion of nonlimited type cannot be limited", N);
14833 elsif No (Interface_List (N)) then
14835 ("completion of tagged private type must be tagged",
14839 elsif Nkind (N) = N_Full_Type_Declaration
14841 Nkind (Type_Definition (N)) = N_Record_Definition
14842 and then Interface_Present (Type_Definition (N))
14845 ("completion of private type cannot be an interface", N);
14848 -- Ada 2005 (AI-251): Private extension declaration of a task
14849 -- type or a protected type. This case arises when covering
14850 -- interface types.
14852 elsif Nkind_In (N, N_Task_Type_Declaration,
14853 N_Protected_Type_Declaration)
14857 elsif Nkind (N) /= N_Full_Type_Declaration
14858 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14861 ("full view of private extension must be an extension", N);
14863 elsif not (Abstract_Present (Parent (Prev)))
14864 and then Abstract_Present (Type_Definition (N))
14867 ("full view of non-abstract extension cannot be abstract", N);
14870 if not In_Private_Part (Current_Scope) then
14872 ("declaration of full view must appear in private part", N);
14875 Copy_And_Swap (Prev, Id);
14876 Set_Has_Private_Declaration (Prev);
14877 Set_Has_Private_Declaration (Id);
14879 -- If no error, propagate freeze_node from private to full view.
14880 -- It may have been generated for an early operational item.
14882 if Present (Freeze_Node (Id))
14883 and then Serious_Errors_Detected = 0
14884 and then No (Full_View (Id))
14886 Set_Freeze_Node (Prev, Freeze_Node (Id));
14887 Set_Freeze_Node (Id, Empty);
14888 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
14891 Set_Full_View (Id, Prev);
14895 -- Verify that full declaration conforms to partial one
14897 if Is_Incomplete_Or_Private_Type (Prev)
14898 and then Present (Discriminant_Specifications (Prev_Par))
14900 if Present (Discriminant_Specifications (N)) then
14901 if Ekind (Prev) = E_Incomplete_Type then
14902 Check_Discriminant_Conformance (N, Prev, Prev);
14904 Check_Discriminant_Conformance (N, Prev, Id);
14909 ("missing discriminants in full type declaration", N);
14911 -- To avoid cascaded errors on subsequent use, share the
14912 -- discriminants of the partial view.
14914 Set_Discriminant_Specifications (N,
14915 Discriminant_Specifications (Prev_Par));
14919 -- A prior untagged partial view can have an associated class-wide
14920 -- type due to use of the class attribute, and in this case the full
14921 -- type must also be tagged. This Ada 95 usage is deprecated in favor
14922 -- of incomplete tagged declarations, but we check for it.
14925 and then (Is_Tagged_Type (Prev)
14926 or else Present (Class_Wide_Type (Prev)))
14928 -- Ada 2012 (AI05-0162): A private type may be the completion of
14929 -- an incomplete type
14931 if Ada_Version >= Ada_2012
14932 and then Is_Incomplete_Type (Prev)
14933 and then Nkind_In (N, N_Private_Type_Declaration,
14934 N_Private_Extension_Declaration)
14936 -- No need to check private extensions since they are tagged
14938 if Nkind (N) = N_Private_Type_Declaration
14939 and then not Tagged_Present (N)
14944 -- The full declaration is either a tagged type (including
14945 -- a synchronized type that implements interfaces) or a
14946 -- type extension, otherwise this is an error.
14948 elsif Nkind_In (N, N_Task_Type_Declaration,
14949 N_Protected_Type_Declaration)
14951 if No (Interface_List (N))
14952 and then not Error_Posted (N)
14957 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
14959 -- Indicate that the previous declaration (tagged incomplete
14960 -- or private declaration) requires the same on the full one.
14962 if not Tagged_Present (Type_Definition (N)) then
14964 Set_Is_Tagged_Type (Id);
14967 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
14968 if No (Record_Extension_Part (Type_Definition (N))) then
14970 ("full declaration of } must be a record extension",
14973 -- Set some attributes to produce a usable full view
14975 Set_Is_Tagged_Type (Id);
14985 end Find_Type_Name;
14987 -------------------------
14988 -- Find_Type_Of_Object --
14989 -------------------------
14991 function Find_Type_Of_Object
14992 (Obj_Def : Node_Id;
14993 Related_Nod : Node_Id) return Entity_Id
14995 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
14996 P : Node_Id := Parent (Obj_Def);
15001 -- If the parent is a component_definition node we climb to the
15002 -- component_declaration node
15004 if Nkind (P) = N_Component_Definition then
15008 -- Case of an anonymous array subtype
15010 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15011 N_Unconstrained_Array_Definition)
15014 Array_Type_Declaration (T, Obj_Def);
15016 -- Create an explicit subtype whenever possible
15018 elsif Nkind (P) /= N_Component_Declaration
15019 and then Def_Kind = N_Subtype_Indication
15021 -- Base name of subtype on object name, which will be unique in
15022 -- the current scope.
15024 -- If this is a duplicate declaration, return base type, to avoid
15025 -- generating duplicate anonymous types.
15027 if Error_Posted (P) then
15028 Analyze (Subtype_Mark (Obj_Def));
15029 return Entity (Subtype_Mark (Obj_Def));
15034 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15036 T := Make_Defining_Identifier (Sloc (P), Nam);
15038 Insert_Action (Obj_Def,
15039 Make_Subtype_Declaration (Sloc (P),
15040 Defining_Identifier => T,
15041 Subtype_Indication => Relocate_Node (Obj_Def)));
15043 -- This subtype may need freezing, and this will not be done
15044 -- automatically if the object declaration is not in declarative
15045 -- part. Since this is an object declaration, the type cannot always
15046 -- be frozen here. Deferred constants do not freeze their type
15047 -- (which often enough will be private).
15049 if Nkind (P) = N_Object_Declaration
15050 and then Constant_Present (P)
15051 and then No (Expression (P))
15055 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15058 -- Ada 2005 AI-406: the object definition in an object declaration
15059 -- can be an access definition.
15061 elsif Def_Kind = N_Access_Definition then
15062 T := Access_Definition (Related_Nod, Obj_Def);
15063 Set_Is_Local_Anonymous_Access (T);
15065 -- Otherwise, the object definition is just a subtype_mark
15068 T := Process_Subtype (Obj_Def, Related_Nod);
15070 -- If expansion is disabled an object definition that is an aggregate
15071 -- will not get expanded and may lead to scoping problems in the back
15072 -- end, if the object is referenced in an inner scope. In that case
15073 -- create an itype reference for the object definition now. This
15074 -- may be redundant in some cases, but harmless.
15077 and then Nkind (Related_Nod) = N_Object_Declaration
15080 Build_Itype_Reference (T, Related_Nod);
15085 end Find_Type_Of_Object;
15087 --------------------------------
15088 -- Find_Type_Of_Subtype_Indic --
15089 --------------------------------
15091 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15095 -- Case of subtype mark with a constraint
15097 if Nkind (S) = N_Subtype_Indication then
15098 Find_Type (Subtype_Mark (S));
15099 Typ := Entity (Subtype_Mark (S));
15102 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15105 ("incorrect constraint for this kind of type", Constraint (S));
15106 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15109 -- Otherwise we have a subtype mark without a constraint
15111 elsif Error_Posted (S) then
15112 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15120 -- Check No_Wide_Characters restriction
15122 Check_Wide_Character_Restriction (Typ, S);
15125 end Find_Type_Of_Subtype_Indic;
15127 -------------------------------------
15128 -- Floating_Point_Type_Declaration --
15129 -------------------------------------
15131 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15132 Digs : constant Node_Id := Digits_Expression (Def);
15133 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15135 Base_Typ : Entity_Id;
15136 Implicit_Base : Entity_Id;
15139 function Can_Derive_From (E : Entity_Id) return Boolean;
15140 -- Find if given digits value, and possibly a specified range, allows
15141 -- derivation from specified type
15143 function Find_Base_Type return Entity_Id;
15144 -- Find a predefined base type that Def can derive from, or generate
15145 -- an error and substitute Long_Long_Float if none exists.
15147 ---------------------
15148 -- Can_Derive_From --
15149 ---------------------
15151 function Can_Derive_From (E : Entity_Id) return Boolean is
15152 Spec : constant Entity_Id := Real_Range_Specification (Def);
15155 if Digs_Val > Digits_Value (E) then
15159 if Present (Spec) then
15160 if Expr_Value_R (Type_Low_Bound (E)) >
15161 Expr_Value_R (Low_Bound (Spec))
15166 if Expr_Value_R (Type_High_Bound (E)) <
15167 Expr_Value_R (High_Bound (Spec))
15174 end Can_Derive_From;
15176 --------------------
15177 -- Find_Base_Type --
15178 --------------------
15180 function Find_Base_Type return Entity_Id is
15181 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15184 -- Iterate over the predefined types in order, returning the first
15185 -- one that Def can derive from.
15187 while Present (Choice) loop
15188 if Can_Derive_From (Node (Choice)) then
15189 return Node (Choice);
15192 Next_Elmt (Choice);
15195 -- If we can't derive from any existing type, use Long_Long_Float
15196 -- and give appropriate message explaining the problem.
15198 if Digs_Val > Max_Digs_Val then
15199 -- It might be the case that there is a type with the requested
15200 -- range, just not the combination of digits and range.
15203 ("no predefined type has requested range and precision",
15204 Real_Range_Specification (Def));
15208 ("range too large for any predefined type",
15209 Real_Range_Specification (Def));
15212 return Standard_Long_Long_Float;
15213 end Find_Base_Type;
15215 -- Start of processing for Floating_Point_Type_Declaration
15218 Check_Restriction (No_Floating_Point, Def);
15220 -- Create an implicit base type
15223 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15225 -- Analyze and verify digits value
15227 Analyze_And_Resolve (Digs, Any_Integer);
15228 Check_Digits_Expression (Digs);
15229 Digs_Val := Expr_Value (Digs);
15231 -- Process possible range spec and find correct type to derive from
15233 Process_Real_Range_Specification (Def);
15235 -- Check that requested number of digits is not too high.
15237 if Digs_Val > Max_Digs_Val then
15238 -- The check for Max_Base_Digits may be somewhat expensive, as it
15239 -- requires reading System, so only do it when necessary.
15242 Max_Base_Digits : constant Uint :=
15245 (Parent (RTE (RE_Max_Base_Digits))));
15248 if Digs_Val > Max_Base_Digits then
15249 Error_Msg_Uint_1 := Max_Base_Digits;
15250 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15252 elsif No (Real_Range_Specification (Def)) then
15253 Error_Msg_Uint_1 := Max_Digs_Val;
15254 Error_Msg_N ("types with more than ^ digits need range spec "
15255 & "('R'M 3.5.7(6))", Digs);
15260 -- Find a suitable type to derive from or complain and use a substitute
15262 Base_Typ := Find_Base_Type;
15264 -- If there are bounds given in the declaration use them as the bounds
15265 -- of the type, otherwise use the bounds of the predefined base type
15266 -- that was chosen based on the Digits value.
15268 if Present (Real_Range_Specification (Def)) then
15269 Set_Scalar_Range (T, Real_Range_Specification (Def));
15270 Set_Is_Constrained (T);
15272 -- The bounds of this range must be converted to machine numbers
15273 -- in accordance with RM 4.9(38).
15275 Bound := Type_Low_Bound (T);
15277 if Nkind (Bound) = N_Real_Literal then
15279 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15280 Set_Is_Machine_Number (Bound);
15283 Bound := Type_High_Bound (T);
15285 if Nkind (Bound) = N_Real_Literal then
15287 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15288 Set_Is_Machine_Number (Bound);
15292 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15295 -- Complete definition of implicit base and declared first subtype
15297 Set_Etype (Implicit_Base, Base_Typ);
15299 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15300 Set_Size_Info (Implicit_Base, (Base_Typ));
15301 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15302 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15303 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15304 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15306 Set_Ekind (T, E_Floating_Point_Subtype);
15307 Set_Etype (T, Implicit_Base);
15309 Set_Size_Info (T, (Implicit_Base));
15310 Set_RM_Size (T, RM_Size (Implicit_Base));
15311 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15312 Set_Digits_Value (T, Digs_Val);
15313 end Floating_Point_Type_Declaration;
15315 ----------------------------
15316 -- Get_Discriminant_Value --
15317 ----------------------------
15319 -- This is the situation:
15321 -- There is a non-derived type
15323 -- type T0 (Dx, Dy, Dz...)
15325 -- There are zero or more levels of derivation, with each derivation
15326 -- either purely inheriting the discriminants, or defining its own.
15328 -- type Ti is new Ti-1
15330 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15332 -- subtype Ti is ...
15334 -- The subtype issue is avoided by the use of Original_Record_Component,
15335 -- and the fact that derived subtypes also derive the constraints.
15337 -- This chain leads back from
15339 -- Typ_For_Constraint
15341 -- Typ_For_Constraint has discriminants, and the value for each
15342 -- discriminant is given by its corresponding Elmt of Constraints.
15344 -- Discriminant is some discriminant in this hierarchy
15346 -- We need to return its value
15348 -- We do this by recursively searching each level, and looking for
15349 -- Discriminant. Once we get to the bottom, we start backing up
15350 -- returning the value for it which may in turn be a discriminant
15351 -- further up, so on the backup we continue the substitution.
15353 function Get_Discriminant_Value
15354 (Discriminant : Entity_Id;
15355 Typ_For_Constraint : Entity_Id;
15356 Constraint : Elist_Id) return Node_Id
15358 function Search_Derivation_Levels
15360 Discrim_Values : Elist_Id;
15361 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15362 -- This is the routine that performs the recursive search of levels
15363 -- as described above.
15365 ------------------------------
15366 -- Search_Derivation_Levels --
15367 ------------------------------
15369 function Search_Derivation_Levels
15371 Discrim_Values : Elist_Id;
15372 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15376 Result : Node_Or_Entity_Id;
15377 Result_Entity : Node_Id;
15380 -- If inappropriate type, return Error, this happens only in
15381 -- cascaded error situations, and we want to avoid a blow up.
15383 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15387 -- Look deeper if possible. Use Stored_Constraints only for
15388 -- untagged types. For tagged types use the given constraint.
15389 -- This asymmetry needs explanation???
15391 if not Stored_Discrim_Values
15392 and then Present (Stored_Constraint (Ti))
15393 and then not Is_Tagged_Type (Ti)
15396 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15399 Td : constant Entity_Id := Etype (Ti);
15403 Result := Discriminant;
15406 if Present (Stored_Constraint (Ti)) then
15408 Search_Derivation_Levels
15409 (Td, Stored_Constraint (Ti), True);
15412 Search_Derivation_Levels
15413 (Td, Discrim_Values, Stored_Discrim_Values);
15419 -- Extra underlying places to search, if not found above. For
15420 -- concurrent types, the relevant discriminant appears in the
15421 -- corresponding record. For a type derived from a private type
15422 -- without discriminant, the full view inherits the discriminants
15423 -- of the full view of the parent.
15425 if Result = Discriminant then
15426 if Is_Concurrent_Type (Ti)
15427 and then Present (Corresponding_Record_Type (Ti))
15430 Search_Derivation_Levels (
15431 Corresponding_Record_Type (Ti),
15433 Stored_Discrim_Values);
15435 elsif Is_Private_Type (Ti)
15436 and then not Has_Discriminants (Ti)
15437 and then Present (Full_View (Ti))
15438 and then Etype (Full_View (Ti)) /= Ti
15441 Search_Derivation_Levels (
15444 Stored_Discrim_Values);
15448 -- If Result is not a (reference to a) discriminant, return it,
15449 -- otherwise set Result_Entity to the discriminant.
15451 if Nkind (Result) = N_Defining_Identifier then
15452 pragma Assert (Result = Discriminant);
15453 Result_Entity := Result;
15456 if not Denotes_Discriminant (Result) then
15460 Result_Entity := Entity (Result);
15463 -- See if this level of derivation actually has discriminants
15464 -- because tagged derivations can add them, hence the lower
15465 -- levels need not have any.
15467 if not Has_Discriminants (Ti) then
15471 -- Scan Ti's discriminants for Result_Entity,
15472 -- and return its corresponding value, if any.
15474 Result_Entity := Original_Record_Component (Result_Entity);
15476 Assoc := First_Elmt (Discrim_Values);
15478 if Stored_Discrim_Values then
15479 Disc := First_Stored_Discriminant (Ti);
15481 Disc := First_Discriminant (Ti);
15484 while Present (Disc) loop
15485 pragma Assert (Present (Assoc));
15487 if Original_Record_Component (Disc) = Result_Entity then
15488 return Node (Assoc);
15493 if Stored_Discrim_Values then
15494 Next_Stored_Discriminant (Disc);
15496 Next_Discriminant (Disc);
15500 -- Could not find it
15503 end Search_Derivation_Levels;
15507 Result : Node_Or_Entity_Id;
15509 -- Start of processing for Get_Discriminant_Value
15512 -- ??? This routine is a gigantic mess and will be deleted. For the
15513 -- time being just test for the trivial case before calling recurse.
15515 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15521 D := First_Discriminant (Typ_For_Constraint);
15522 E := First_Elmt (Constraint);
15523 while Present (D) loop
15524 if Chars (D) = Chars (Discriminant) then
15528 Next_Discriminant (D);
15534 Result := Search_Derivation_Levels
15535 (Typ_For_Constraint, Constraint, False);
15537 -- ??? hack to disappear when this routine is gone
15539 if Nkind (Result) = N_Defining_Identifier then
15545 D := First_Discriminant (Typ_For_Constraint);
15546 E := First_Elmt (Constraint);
15547 while Present (D) loop
15548 if Corresponding_Discriminant (D) = Discriminant then
15552 Next_Discriminant (D);
15558 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15560 end Get_Discriminant_Value;
15562 --------------------------
15563 -- Has_Range_Constraint --
15564 --------------------------
15566 function Has_Range_Constraint (N : Node_Id) return Boolean is
15567 C : constant Node_Id := Constraint (N);
15570 if Nkind (C) = N_Range_Constraint then
15573 elsif Nkind (C) = N_Digits_Constraint then
15575 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15577 Present (Range_Constraint (C));
15579 elsif Nkind (C) = N_Delta_Constraint then
15580 return Present (Range_Constraint (C));
15585 end Has_Range_Constraint;
15587 ------------------------
15588 -- Inherit_Components --
15589 ------------------------
15591 function Inherit_Components
15593 Parent_Base : Entity_Id;
15594 Derived_Base : Entity_Id;
15595 Is_Tagged : Boolean;
15596 Inherit_Discr : Boolean;
15597 Discs : Elist_Id) return Elist_Id
15599 Assoc_List : constant Elist_Id := New_Elmt_List;
15601 procedure Inherit_Component
15602 (Old_C : Entity_Id;
15603 Plain_Discrim : Boolean := False;
15604 Stored_Discrim : Boolean := False);
15605 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15606 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15607 -- True, Old_C is a stored discriminant. If they are both false then
15608 -- Old_C is a regular component.
15610 -----------------------
15611 -- Inherit_Component --
15612 -----------------------
15614 procedure Inherit_Component
15615 (Old_C : Entity_Id;
15616 Plain_Discrim : Boolean := False;
15617 Stored_Discrim : Boolean := False)
15619 New_C : constant Entity_Id := New_Copy (Old_C);
15621 Discrim : Entity_Id;
15622 Corr_Discrim : Entity_Id;
15625 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15627 Set_Parent (New_C, Parent (Old_C));
15629 -- Regular discriminants and components must be inserted in the scope
15630 -- of the Derived_Base. Do it here.
15632 if not Stored_Discrim then
15633 Enter_Name (New_C);
15636 -- For tagged types the Original_Record_Component must point to
15637 -- whatever this field was pointing to in the parent type. This has
15638 -- already been achieved by the call to New_Copy above.
15640 if not Is_Tagged then
15641 Set_Original_Record_Component (New_C, New_C);
15644 -- If we have inherited a component then see if its Etype contains
15645 -- references to Parent_Base discriminants. In this case, replace
15646 -- these references with the constraints given in Discs. We do not
15647 -- do this for the partial view of private types because this is
15648 -- not needed (only the components of the full view will be used
15649 -- for code generation) and cause problem. We also avoid this
15650 -- transformation in some error situations.
15652 if Ekind (New_C) = E_Component then
15653 if (Is_Private_Type (Derived_Base)
15654 and then not Is_Generic_Type (Derived_Base))
15655 or else (Is_Empty_Elmt_List (Discs)
15656 and then not Expander_Active)
15658 Set_Etype (New_C, Etype (Old_C));
15661 -- The current component introduces a circularity of the
15664 -- limited with Pack_2;
15665 -- package Pack_1 is
15666 -- type T_1 is tagged record
15667 -- Comp : access Pack_2.T_2;
15673 -- package Pack_2 is
15674 -- type T_2 is new Pack_1.T_1 with ...;
15679 Constrain_Component_Type
15680 (Old_C, Derived_Base, N, Parent_Base, Discs));
15684 -- In derived tagged types it is illegal to reference a non
15685 -- discriminant component in the parent type. To catch this, mark
15686 -- these components with an Ekind of E_Void. This will be reset in
15687 -- Record_Type_Definition after processing the record extension of
15688 -- the derived type.
15690 -- If the declaration is a private extension, there is no further
15691 -- record extension to process, and the components retain their
15692 -- current kind, because they are visible at this point.
15694 if Is_Tagged and then Ekind (New_C) = E_Component
15695 and then Nkind (N) /= N_Private_Extension_Declaration
15697 Set_Ekind (New_C, E_Void);
15700 if Plain_Discrim then
15701 Set_Corresponding_Discriminant (New_C, Old_C);
15702 Build_Discriminal (New_C);
15704 -- If we are explicitly inheriting a stored discriminant it will be
15705 -- completely hidden.
15707 elsif Stored_Discrim then
15708 Set_Corresponding_Discriminant (New_C, Empty);
15709 Set_Discriminal (New_C, Empty);
15710 Set_Is_Completely_Hidden (New_C);
15712 -- Set the Original_Record_Component of each discriminant in the
15713 -- derived base to point to the corresponding stored that we just
15716 Discrim := First_Discriminant (Derived_Base);
15717 while Present (Discrim) loop
15718 Corr_Discrim := Corresponding_Discriminant (Discrim);
15720 -- Corr_Discrim could be missing in an error situation
15722 if Present (Corr_Discrim)
15723 and then Original_Record_Component (Corr_Discrim) = Old_C
15725 Set_Original_Record_Component (Discrim, New_C);
15728 Next_Discriminant (Discrim);
15731 Append_Entity (New_C, Derived_Base);
15734 if not Is_Tagged then
15735 Append_Elmt (Old_C, Assoc_List);
15736 Append_Elmt (New_C, Assoc_List);
15738 end Inherit_Component;
15740 -- Variables local to Inherit_Component
15742 Loc : constant Source_Ptr := Sloc (N);
15744 Parent_Discrim : Entity_Id;
15745 Stored_Discrim : Entity_Id;
15747 Component : Entity_Id;
15749 -- Start of processing for Inherit_Components
15752 if not Is_Tagged then
15753 Append_Elmt (Parent_Base, Assoc_List);
15754 Append_Elmt (Derived_Base, Assoc_List);
15757 -- Inherit parent discriminants if needed
15759 if Inherit_Discr then
15760 Parent_Discrim := First_Discriminant (Parent_Base);
15761 while Present (Parent_Discrim) loop
15762 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15763 Next_Discriminant (Parent_Discrim);
15767 -- Create explicit stored discrims for untagged types when necessary
15769 if not Has_Unknown_Discriminants (Derived_Base)
15770 and then Has_Discriminants (Parent_Base)
15771 and then not Is_Tagged
15774 or else First_Discriminant (Parent_Base) /=
15775 First_Stored_Discriminant (Parent_Base))
15777 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15778 while Present (Stored_Discrim) loop
15779 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15780 Next_Stored_Discriminant (Stored_Discrim);
15784 -- See if we can apply the second transformation for derived types, as
15785 -- explained in point 6. in the comments above Build_Derived_Record_Type
15786 -- This is achieved by appending Derived_Base discriminants into Discs,
15787 -- which has the side effect of returning a non empty Discs list to the
15788 -- caller of Inherit_Components, which is what we want. This must be
15789 -- done for private derived types if there are explicit stored
15790 -- discriminants, to ensure that we can retrieve the values of the
15791 -- constraints provided in the ancestors.
15794 and then Is_Empty_Elmt_List (Discs)
15795 and then Present (First_Discriminant (Derived_Base))
15797 (not Is_Private_Type (Derived_Base)
15798 or else Is_Completely_Hidden
15799 (First_Stored_Discriminant (Derived_Base))
15800 or else Is_Generic_Type (Derived_Base))
15802 D := First_Discriminant (Derived_Base);
15803 while Present (D) loop
15804 Append_Elmt (New_Reference_To (D, Loc), Discs);
15805 Next_Discriminant (D);
15809 -- Finally, inherit non-discriminant components unless they are not
15810 -- visible because defined or inherited from the full view of the
15811 -- parent. Don't inherit the _parent field of the parent type.
15813 Component := First_Entity (Parent_Base);
15814 while Present (Component) loop
15816 -- Ada 2005 (AI-251): Do not inherit components associated with
15817 -- secondary tags of the parent.
15819 if Ekind (Component) = E_Component
15820 and then Present (Related_Type (Component))
15824 elsif Ekind (Component) /= E_Component
15825 or else Chars (Component) = Name_uParent
15829 -- If the derived type is within the parent type's declarative
15830 -- region, then the components can still be inherited even though
15831 -- they aren't visible at this point. This can occur for cases
15832 -- such as within public child units where the components must
15833 -- become visible upon entering the child unit's private part.
15835 elsif not Is_Visible_Component (Component)
15836 and then not In_Open_Scopes (Scope (Parent_Base))
15840 elsif Ekind_In (Derived_Base, E_Private_Type,
15841 E_Limited_Private_Type)
15846 Inherit_Component (Component);
15849 Next_Entity (Component);
15852 -- For tagged derived types, inherited discriminants cannot be used in
15853 -- component declarations of the record extension part. To achieve this
15854 -- we mark the inherited discriminants as not visible.
15856 if Is_Tagged and then Inherit_Discr then
15857 D := First_Discriminant (Derived_Base);
15858 while Present (D) loop
15859 Set_Is_Immediately_Visible (D, False);
15860 Next_Discriminant (D);
15865 end Inherit_Components;
15867 -----------------------
15868 -- Is_Constant_Bound --
15869 -----------------------
15871 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
15873 if Compile_Time_Known_Value (Exp) then
15876 elsif Is_Entity_Name (Exp)
15877 and then Present (Entity (Exp))
15879 return Is_Constant_Object (Entity (Exp))
15880 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
15882 elsif Nkind (Exp) in N_Binary_Op then
15883 return Is_Constant_Bound (Left_Opnd (Exp))
15884 and then Is_Constant_Bound (Right_Opnd (Exp))
15885 and then Scope (Entity (Exp)) = Standard_Standard;
15890 end Is_Constant_Bound;
15892 -----------------------
15893 -- Is_Null_Extension --
15894 -----------------------
15896 function Is_Null_Extension (T : Entity_Id) return Boolean is
15897 Type_Decl : constant Node_Id := Parent (Base_Type (T));
15898 Comp_List : Node_Id;
15902 if Nkind (Type_Decl) /= N_Full_Type_Declaration
15903 or else not Is_Tagged_Type (T)
15904 or else Nkind (Type_Definition (Type_Decl)) /=
15905 N_Derived_Type_Definition
15906 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
15912 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
15914 if Present (Discriminant_Specifications (Type_Decl)) then
15917 elsif Present (Comp_List)
15918 and then Is_Non_Empty_List (Component_Items (Comp_List))
15920 Comp := First (Component_Items (Comp_List));
15922 -- Only user-defined components are relevant. The component list
15923 -- may also contain a parent component and internal components
15924 -- corresponding to secondary tags, but these do not determine
15925 -- whether this is a null extension.
15927 while Present (Comp) loop
15928 if Comes_From_Source (Comp) then
15939 end Is_Null_Extension;
15941 ------------------------------
15942 -- Is_Valid_Constraint_Kind --
15943 ------------------------------
15945 function Is_Valid_Constraint_Kind
15946 (T_Kind : Type_Kind;
15947 Constraint_Kind : Node_Kind) return Boolean
15951 when Enumeration_Kind |
15953 return Constraint_Kind = N_Range_Constraint;
15955 when Decimal_Fixed_Point_Kind =>
15956 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
15957 N_Range_Constraint);
15959 when Ordinary_Fixed_Point_Kind =>
15960 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
15961 N_Range_Constraint);
15964 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
15965 N_Range_Constraint);
15972 E_Incomplete_Type |
15975 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
15978 return True; -- Error will be detected later
15980 end Is_Valid_Constraint_Kind;
15982 --------------------------
15983 -- Is_Visible_Component --
15984 --------------------------
15986 function Is_Visible_Component (C : Entity_Id) return Boolean is
15987 Original_Comp : Entity_Id := Empty;
15988 Original_Scope : Entity_Id;
15989 Type_Scope : Entity_Id;
15991 function Is_Local_Type (Typ : Entity_Id) return Boolean;
15992 -- Check whether parent type of inherited component is declared locally,
15993 -- possibly within a nested package or instance. The current scope is
15994 -- the derived record itself.
15996 -------------------
15997 -- Is_Local_Type --
15998 -------------------
16000 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16004 Scop := Scope (Typ);
16005 while Present (Scop)
16006 and then Scop /= Standard_Standard
16008 if Scop = Scope (Current_Scope) then
16012 Scop := Scope (Scop);
16018 -- Start of processing for Is_Visible_Component
16021 if Ekind_In (C, E_Component, E_Discriminant) then
16022 Original_Comp := Original_Record_Component (C);
16025 if No (Original_Comp) then
16027 -- Premature usage, or previous error
16032 Original_Scope := Scope (Original_Comp);
16033 Type_Scope := Scope (Base_Type (Scope (C)));
16036 -- This test only concerns tagged types
16038 if not Is_Tagged_Type (Original_Scope) then
16041 -- If it is _Parent or _Tag, there is no visibility issue
16043 elsif not Comes_From_Source (Original_Comp) then
16046 -- If we are in the body of an instantiation, the component is visible
16047 -- even when the parent type (possibly defined in an enclosing unit or
16048 -- in a parent unit) might not.
16050 elsif In_Instance_Body then
16053 -- Discriminants are always visible
16055 elsif Ekind (Original_Comp) = E_Discriminant
16056 and then not Has_Unknown_Discriminants (Original_Scope)
16060 -- If the component has been declared in an ancestor which is currently
16061 -- a private type, then it is not visible. The same applies if the
16062 -- component's containing type is not in an open scope and the original
16063 -- component's enclosing type is a visible full view of a private type
16064 -- (which can occur in cases where an attempt is being made to reference
16065 -- a component in a sibling package that is inherited from a visible
16066 -- component of a type in an ancestor package; the component in the
16067 -- sibling package should not be visible even though the component it
16068 -- inherited from is visible). This does not apply however in the case
16069 -- where the scope of the type is a private child unit, or when the
16070 -- parent comes from a local package in which the ancestor is currently
16071 -- visible. The latter suppression of visibility is needed for cases
16072 -- that are tested in B730006.
16074 elsif Is_Private_Type (Original_Scope)
16076 (not Is_Private_Descendant (Type_Scope)
16077 and then not In_Open_Scopes (Type_Scope)
16078 and then Has_Private_Declaration (Original_Scope))
16080 -- If the type derives from an entity in a formal package, there
16081 -- are no additional visible components.
16083 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16084 N_Formal_Package_Declaration
16088 -- if we are not in the private part of the current package, there
16089 -- are no additional visible components.
16091 elsif Ekind (Scope (Current_Scope)) = E_Package
16092 and then not In_Private_Part (Scope (Current_Scope))
16097 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16098 and then In_Open_Scopes (Scope (Original_Scope))
16099 and then Is_Local_Type (Type_Scope);
16102 -- There is another weird way in which a component may be invisible
16103 -- when the private and the full view are not derived from the same
16104 -- ancestor. Here is an example :
16106 -- type A1 is tagged record F1 : integer; end record;
16107 -- type A2 is new A1 with record F2 : integer; end record;
16108 -- type T is new A1 with private;
16110 -- type T is new A2 with null record;
16112 -- In this case, the full view of T inherits F1 and F2 but the private
16113 -- view inherits only F1
16117 Ancestor : Entity_Id := Scope (C);
16121 if Ancestor = Original_Scope then
16123 elsif Ancestor = Etype (Ancestor) then
16127 Ancestor := Etype (Ancestor);
16131 end Is_Visible_Component;
16133 --------------------------
16134 -- Make_Class_Wide_Type --
16135 --------------------------
16137 procedure Make_Class_Wide_Type (T : Entity_Id) is
16138 CW_Type : Entity_Id;
16140 Next_E : Entity_Id;
16143 -- The class wide type can have been defined by the partial view, in
16144 -- which case everything is already done.
16146 if Present (Class_Wide_Type (T)) then
16151 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16153 -- Inherit root type characteristics
16155 CW_Name := Chars (CW_Type);
16156 Next_E := Next_Entity (CW_Type);
16157 Copy_Node (T, CW_Type);
16158 Set_Comes_From_Source (CW_Type, False);
16159 Set_Chars (CW_Type, CW_Name);
16160 Set_Parent (CW_Type, Parent (T));
16161 Set_Next_Entity (CW_Type, Next_E);
16163 -- Ensure we have a new freeze node for the class-wide type. The partial
16164 -- view may have freeze action of its own, requiring a proper freeze
16165 -- node, and the same freeze node cannot be shared between the two
16168 Set_Has_Delayed_Freeze (CW_Type);
16169 Set_Freeze_Node (CW_Type, Empty);
16171 -- Customize the class-wide type: It has no prim. op., it cannot be
16172 -- abstract and its Etype points back to the specific root type.
16174 Set_Ekind (CW_Type, E_Class_Wide_Type);
16175 Set_Is_Tagged_Type (CW_Type, True);
16176 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16177 Set_Is_Abstract_Type (CW_Type, False);
16178 Set_Is_Constrained (CW_Type, False);
16179 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16181 if Ekind (T) = E_Class_Wide_Subtype then
16182 Set_Etype (CW_Type, Etype (Base_Type (T)));
16184 Set_Etype (CW_Type, T);
16187 -- If this is the class_wide type of a constrained subtype, it does
16188 -- not have discriminants.
16190 Set_Has_Discriminants (CW_Type,
16191 Has_Discriminants (T) and then not Is_Constrained (T));
16193 Set_Has_Unknown_Discriminants (CW_Type, True);
16194 Set_Class_Wide_Type (T, CW_Type);
16195 Set_Equivalent_Type (CW_Type, Empty);
16197 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16199 Set_Class_Wide_Type (CW_Type, CW_Type);
16200 end Make_Class_Wide_Type;
16206 procedure Make_Index
16208 Related_Nod : Node_Id;
16209 Related_Id : Entity_Id := Empty;
16210 Suffix_Index : Nat := 1;
16211 In_Iter_Schm : Boolean := False)
16215 Def_Id : Entity_Id := Empty;
16216 Found : Boolean := False;
16219 -- For a discrete range used in a constrained array definition and
16220 -- defined by a range, an implicit conversion to the predefined type
16221 -- INTEGER is assumed if each bound is either a numeric literal, a named
16222 -- number, or an attribute, and the type of both bounds (prior to the
16223 -- implicit conversion) is the type universal_integer. Otherwise, both
16224 -- bounds must be of the same discrete type, other than universal
16225 -- integer; this type must be determinable independently of the
16226 -- context, but using the fact that the type must be discrete and that
16227 -- both bounds must have the same type.
16229 -- Character literals also have a universal type in the absence of
16230 -- of additional context, and are resolved to Standard_Character.
16232 if Nkind (I) = N_Range then
16234 -- The index is given by a range constraint. The bounds are known
16235 -- to be of a consistent type.
16237 if not Is_Overloaded (I) then
16240 -- For universal bounds, choose the specific predefined type
16242 if T = Universal_Integer then
16243 T := Standard_Integer;
16245 elsif T = Any_Character then
16246 Ambiguous_Character (Low_Bound (I));
16248 T := Standard_Character;
16251 -- The node may be overloaded because some user-defined operators
16252 -- are available, but if a universal interpretation exists it is
16253 -- also the selected one.
16255 elsif Universal_Interpretation (I) = Universal_Integer then
16256 T := Standard_Integer;
16262 Ind : Interp_Index;
16266 Get_First_Interp (I, Ind, It);
16267 while Present (It.Typ) loop
16268 if Is_Discrete_Type (It.Typ) then
16271 and then not Covers (It.Typ, T)
16272 and then not Covers (T, It.Typ)
16274 Error_Msg_N ("ambiguous bounds in discrete range", I);
16282 Get_Next_Interp (Ind, It);
16285 if T = Any_Type then
16286 Error_Msg_N ("discrete type required for range", I);
16287 Set_Etype (I, Any_Type);
16290 elsif T = Universal_Integer then
16291 T := Standard_Integer;
16296 if not Is_Discrete_Type (T) then
16297 Error_Msg_N ("discrete type required for range", I);
16298 Set_Etype (I, Any_Type);
16302 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16303 and then Attribute_Name (Low_Bound (I)) = Name_First
16304 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16305 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16306 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16308 -- The type of the index will be the type of the prefix, as long
16309 -- as the upper bound is 'Last of the same type.
16311 Def_Id := Entity (Prefix (Low_Bound (I)));
16313 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16314 or else Attribute_Name (High_Bound (I)) /= Name_Last
16315 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16316 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16323 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16325 elsif Nkind (I) = N_Subtype_Indication then
16327 -- The index is given by a subtype with a range constraint
16329 T := Base_Type (Entity (Subtype_Mark (I)));
16331 if not Is_Discrete_Type (T) then
16332 Error_Msg_N ("discrete type required for range", I);
16333 Set_Etype (I, Any_Type);
16337 R := Range_Expression (Constraint (I));
16340 Process_Range_Expr_In_Decl
16341 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16343 elsif Nkind (I) = N_Attribute_Reference then
16345 -- The parser guarantees that the attribute is a RANGE attribute
16347 -- If the node denotes the range of a type mark, that is also the
16348 -- resulting type, and we do no need to create an Itype for it.
16350 if Is_Entity_Name (Prefix (I))
16351 and then Comes_From_Source (I)
16352 and then Is_Type (Entity (Prefix (I)))
16353 and then Is_Discrete_Type (Entity (Prefix (I)))
16355 Def_Id := Entity (Prefix (I));
16358 Analyze_And_Resolve (I);
16362 -- If none of the above, must be a subtype. We convert this to a
16363 -- range attribute reference because in the case of declared first
16364 -- named subtypes, the types in the range reference can be different
16365 -- from the type of the entity. A range attribute normalizes the
16366 -- reference and obtains the correct types for the bounds.
16368 -- This transformation is in the nature of an expansion, is only
16369 -- done if expansion is active. In particular, it is not done on
16370 -- formal generic types, because we need to retain the name of the
16371 -- original index for instantiation purposes.
16374 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16375 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16376 Set_Etype (I, Any_Integer);
16380 -- The type mark may be that of an incomplete type. It is only
16381 -- now that we can get the full view, previous analysis does
16382 -- not look specifically for a type mark.
16384 Set_Entity (I, Get_Full_View (Entity (I)));
16385 Set_Etype (I, Entity (I));
16386 Def_Id := Entity (I);
16388 if not Is_Discrete_Type (Def_Id) then
16389 Error_Msg_N ("discrete type required for index", I);
16390 Set_Etype (I, Any_Type);
16395 if Expander_Active then
16397 Make_Attribute_Reference (Sloc (I),
16398 Attribute_Name => Name_Range,
16399 Prefix => Relocate_Node (I)));
16401 -- The original was a subtype mark that does not freeze. This
16402 -- means that the rewritten version must not freeze either.
16404 Set_Must_Not_Freeze (I);
16405 Set_Must_Not_Freeze (Prefix (I));
16407 -- Is order critical??? if so, document why, if not
16408 -- use Analyze_And_Resolve
16410 Analyze_And_Resolve (I);
16414 -- If expander is inactive, type is legal, nothing else to construct
16421 if not Is_Discrete_Type (T) then
16422 Error_Msg_N ("discrete type required for range", I);
16423 Set_Etype (I, Any_Type);
16426 elsif T = Any_Type then
16427 Set_Etype (I, Any_Type);
16431 -- We will now create the appropriate Itype to describe the range, but
16432 -- first a check. If we originally had a subtype, then we just label
16433 -- the range with this subtype. Not only is there no need to construct
16434 -- a new subtype, but it is wrong to do so for two reasons:
16436 -- 1. A legality concern, if we have a subtype, it must not freeze,
16437 -- and the Itype would cause freezing incorrectly
16439 -- 2. An efficiency concern, if we created an Itype, it would not be
16440 -- recognized as the same type for the purposes of eliminating
16441 -- checks in some circumstances.
16443 -- We signal this case by setting the subtype entity in Def_Id
16445 if No (Def_Id) then
16447 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16448 Set_Etype (Def_Id, Base_Type (T));
16450 if Is_Signed_Integer_Type (T) then
16451 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16453 elsif Is_Modular_Integer_Type (T) then
16454 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16457 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16458 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16459 Set_First_Literal (Def_Id, First_Literal (T));
16462 Set_Size_Info (Def_Id, (T));
16463 Set_RM_Size (Def_Id, RM_Size (T));
16464 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16466 Set_Scalar_Range (Def_Id, R);
16467 Conditional_Delay (Def_Id, T);
16469 -- In the subtype indication case, if the immediate parent of the
16470 -- new subtype is non-static, then the subtype we create is non-
16471 -- static, even if its bounds are static.
16473 if Nkind (I) = N_Subtype_Indication
16474 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16476 Set_Is_Non_Static_Subtype (Def_Id);
16480 -- Final step is to label the index with this constructed type
16482 Set_Etype (I, Def_Id);
16485 ------------------------------
16486 -- Modular_Type_Declaration --
16487 ------------------------------
16489 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16490 Mod_Expr : constant Node_Id := Expression (Def);
16493 procedure Set_Modular_Size (Bits : Int);
16494 -- Sets RM_Size to Bits, and Esize to normal word size above this
16496 ----------------------
16497 -- Set_Modular_Size --
16498 ----------------------
16500 procedure Set_Modular_Size (Bits : Int) is
16502 Set_RM_Size (T, UI_From_Int (Bits));
16507 elsif Bits <= 16 then
16508 Init_Esize (T, 16);
16510 elsif Bits <= 32 then
16511 Init_Esize (T, 32);
16514 Init_Esize (T, System_Max_Binary_Modulus_Power);
16517 if not Non_Binary_Modulus (T)
16518 and then Esize (T) = RM_Size (T)
16520 Set_Is_Known_Valid (T);
16522 end Set_Modular_Size;
16524 -- Start of processing for Modular_Type_Declaration
16527 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16529 Set_Ekind (T, E_Modular_Integer_Type);
16530 Init_Alignment (T);
16531 Set_Is_Constrained (T);
16533 if not Is_OK_Static_Expression (Mod_Expr) then
16534 Flag_Non_Static_Expr
16535 ("non-static expression used for modular type bound!", Mod_Expr);
16536 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16538 M_Val := Expr_Value (Mod_Expr);
16542 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16543 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16546 Set_Modulus (T, M_Val);
16548 -- Create bounds for the modular type based on the modulus given in
16549 -- the type declaration and then analyze and resolve those bounds.
16551 Set_Scalar_Range (T,
16552 Make_Range (Sloc (Mod_Expr),
16553 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16554 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16556 -- Properly analyze the literals for the range. We do this manually
16557 -- because we can't go calling Resolve, since we are resolving these
16558 -- bounds with the type, and this type is certainly not complete yet!
16560 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16561 Set_Etype (High_Bound (Scalar_Range (T)), T);
16562 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16563 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16565 -- Loop through powers of two to find number of bits required
16567 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16571 if M_Val = 2 ** Bits then
16572 Set_Modular_Size (Bits);
16577 elsif M_Val < 2 ** Bits then
16578 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16579 Set_Non_Binary_Modulus (T);
16581 if Bits > System_Max_Nonbinary_Modulus_Power then
16582 Error_Msg_Uint_1 :=
16583 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16585 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16586 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16590 -- In the non-binary case, set size as per RM 13.3(55)
16592 Set_Modular_Size (Bits);
16599 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16600 -- so we just signal an error and set the maximum size.
16602 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16603 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16605 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16606 Init_Alignment (T);
16608 end Modular_Type_Declaration;
16610 --------------------------
16611 -- New_Concatenation_Op --
16612 --------------------------
16614 procedure New_Concatenation_Op (Typ : Entity_Id) is
16615 Loc : constant Source_Ptr := Sloc (Typ);
16618 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16619 -- Create abbreviated declaration for the formal of a predefined
16620 -- Operator 'Op' of type 'Typ'
16622 --------------------
16623 -- Make_Op_Formal --
16624 --------------------
16626 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16627 Formal : Entity_Id;
16629 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16630 Set_Etype (Formal, Typ);
16631 Set_Mechanism (Formal, Default_Mechanism);
16633 end Make_Op_Formal;
16635 -- Start of processing for New_Concatenation_Op
16638 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16640 Set_Ekind (Op, E_Operator);
16641 Set_Scope (Op, Current_Scope);
16642 Set_Etype (Op, Typ);
16643 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16644 Set_Is_Immediately_Visible (Op);
16645 Set_Is_Intrinsic_Subprogram (Op);
16646 Set_Has_Completion (Op);
16647 Append_Entity (Op, Current_Scope);
16649 Set_Name_Entity_Id (Name_Op_Concat, Op);
16651 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16652 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16653 end New_Concatenation_Op;
16655 -------------------------
16656 -- OK_For_Limited_Init --
16657 -------------------------
16659 -- ???Check all calls of this, and compare the conditions under which it's
16662 function OK_For_Limited_Init
16664 Exp : Node_Id) return Boolean
16667 return Is_CPP_Constructor_Call (Exp)
16668 or else (Ada_Version >= Ada_2005
16669 and then not Debug_Flag_Dot_L
16670 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16671 end OK_For_Limited_Init;
16673 -------------------------------
16674 -- OK_For_Limited_Init_In_05 --
16675 -------------------------------
16677 function OK_For_Limited_Init_In_05
16679 Exp : Node_Id) return Boolean
16682 -- An object of a limited interface type can be initialized with any
16683 -- expression of a nonlimited descendant type.
16685 if Is_Class_Wide_Type (Typ)
16686 and then Is_Limited_Interface (Typ)
16687 and then not Is_Limited_Type (Etype (Exp))
16692 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16693 -- case of limited aggregates (including extension aggregates), and
16694 -- function calls. The function call may have been given in prefixed
16695 -- notation, in which case the original node is an indexed component.
16696 -- If the function is parameterless, the original node was an explicit
16699 case Nkind (Original_Node (Exp)) is
16700 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16703 when N_Qualified_Expression =>
16705 OK_For_Limited_Init_In_05
16706 (Typ, Expression (Original_Node (Exp)));
16708 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16709 -- with a function call, the expander has rewritten the call into an
16710 -- N_Type_Conversion node to force displacement of the pointer to
16711 -- reference the component containing the secondary dispatch table.
16712 -- Otherwise a type conversion is not a legal context.
16713 -- A return statement for a build-in-place function returning a
16714 -- synchronized type also introduces an unchecked conversion.
16716 when N_Type_Conversion |
16717 N_Unchecked_Type_Conversion =>
16718 return not Comes_From_Source (Exp)
16720 OK_For_Limited_Init_In_05
16721 (Typ, Expression (Original_Node (Exp)));
16723 when N_Indexed_Component |
16724 N_Selected_Component |
16725 N_Explicit_Dereference =>
16726 return Nkind (Exp) = N_Function_Call;
16728 -- A use of 'Input is a function call, hence allowed. Normally the
16729 -- attribute will be changed to a call, but the attribute by itself
16730 -- can occur with -gnatc.
16732 when N_Attribute_Reference =>
16733 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16738 end OK_For_Limited_Init_In_05;
16740 -------------------------------------------
16741 -- Ordinary_Fixed_Point_Type_Declaration --
16742 -------------------------------------------
16744 procedure Ordinary_Fixed_Point_Type_Declaration
16748 Loc : constant Source_Ptr := Sloc (Def);
16749 Delta_Expr : constant Node_Id := Delta_Expression (Def);
16750 RRS : constant Node_Id := Real_Range_Specification (Def);
16751 Implicit_Base : Entity_Id;
16758 Check_Restriction (No_Fixed_Point, Def);
16760 -- Create implicit base type
16763 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
16764 Set_Etype (Implicit_Base, Implicit_Base);
16766 -- Analyze and process delta expression
16768 Analyze_And_Resolve (Delta_Expr, Any_Real);
16770 Check_Delta_Expression (Delta_Expr);
16771 Delta_Val := Expr_Value_R (Delta_Expr);
16773 Set_Delta_Value (Implicit_Base, Delta_Val);
16775 -- Compute default small from given delta, which is the largest power
16776 -- of two that does not exceed the given delta value.
16786 if Delta_Val < Ureal_1 then
16787 while Delta_Val < Tmp loop
16788 Tmp := Tmp / Ureal_2;
16789 Scale := Scale + 1;
16794 Tmp := Tmp * Ureal_2;
16795 exit when Tmp > Delta_Val;
16796 Scale := Scale - 1;
16800 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
16803 Set_Small_Value (Implicit_Base, Small_Val);
16805 -- If no range was given, set a dummy range
16807 if RRS <= Empty_Or_Error then
16808 Low_Val := -Small_Val;
16809 High_Val := Small_Val;
16811 -- Otherwise analyze and process given range
16815 Low : constant Node_Id := Low_Bound (RRS);
16816 High : constant Node_Id := High_Bound (RRS);
16819 Analyze_And_Resolve (Low, Any_Real);
16820 Analyze_And_Resolve (High, Any_Real);
16821 Check_Real_Bound (Low);
16822 Check_Real_Bound (High);
16824 -- Obtain and set the range
16826 Low_Val := Expr_Value_R (Low);
16827 High_Val := Expr_Value_R (High);
16829 if Low_Val > High_Val then
16830 Error_Msg_NE ("?fixed point type& has null range", Def, T);
16835 -- The range for both the implicit base and the declared first subtype
16836 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
16837 -- set a temporary range in place. Note that the bounds of the base
16838 -- type will be widened to be symmetrical and to fill the available
16839 -- bits when the type is frozen.
16841 -- We could do this with all discrete types, and probably should, but
16842 -- we absolutely have to do it for fixed-point, since the end-points
16843 -- of the range and the size are determined by the small value, which
16844 -- could be reset before the freeze point.
16846 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
16847 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
16849 -- Complete definition of first subtype
16851 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
16852 Set_Etype (T, Implicit_Base);
16853 Init_Size_Align (T);
16854 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16855 Set_Small_Value (T, Small_Val);
16856 Set_Delta_Value (T, Delta_Val);
16857 Set_Is_Constrained (T);
16859 end Ordinary_Fixed_Point_Type_Declaration;
16861 ----------------------------------------
16862 -- Prepare_Private_Subtype_Completion --
16863 ----------------------------------------
16865 procedure Prepare_Private_Subtype_Completion
16867 Related_Nod : Node_Id)
16869 Id_B : constant Entity_Id := Base_Type (Id);
16870 Full_B : constant Entity_Id := Full_View (Id_B);
16874 if Present (Full_B) then
16876 -- The Base_Type is already completed, we can complete the subtype
16877 -- now. We have to create a new entity with the same name, Thus we
16878 -- can't use Create_Itype.
16880 -- This is messy, should be fixed ???
16882 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
16883 Set_Is_Itype (Full);
16884 Set_Associated_Node_For_Itype (Full, Related_Nod);
16885 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
16888 -- The parent subtype may be private, but the base might not, in some
16889 -- nested instances. In that case, the subtype does not need to be
16890 -- exchanged. It would still be nice to make private subtypes and their
16891 -- bases consistent at all times ???
16893 if Is_Private_Type (Id_B) then
16894 Append_Elmt (Id, Private_Dependents (Id_B));
16897 end Prepare_Private_Subtype_Completion;
16899 ---------------------------
16900 -- Process_Discriminants --
16901 ---------------------------
16903 procedure Process_Discriminants
16905 Prev : Entity_Id := Empty)
16907 Elist : constant Elist_Id := New_Elmt_List;
16910 Discr_Number : Uint;
16911 Discr_Type : Entity_Id;
16912 Default_Present : Boolean := False;
16913 Default_Not_Present : Boolean := False;
16916 -- A composite type other than an array type can have discriminants.
16917 -- On entry, the current scope is the composite type.
16919 -- The discriminants are initially entered into the scope of the type
16920 -- via Enter_Name with the default Ekind of E_Void to prevent premature
16921 -- use, as explained at the end of this procedure.
16923 Discr := First (Discriminant_Specifications (N));
16924 while Present (Discr) loop
16925 Enter_Name (Defining_Identifier (Discr));
16927 -- For navigation purposes we add a reference to the discriminant
16928 -- in the entity for the type. If the current declaration is a
16929 -- completion, place references on the partial view. Otherwise the
16930 -- type is the current scope.
16932 if Present (Prev) then
16934 -- The references go on the partial view, if present. If the
16935 -- partial view has discriminants, the references have been
16936 -- generated already.
16938 if not Has_Discriminants (Prev) then
16939 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
16943 (Current_Scope, Defining_Identifier (Discr), 'd');
16946 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
16947 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
16949 -- Ada 2005 (AI-254)
16951 if Present (Access_To_Subprogram_Definition
16952 (Discriminant_Type (Discr)))
16953 and then Protected_Present (Access_To_Subprogram_Definition
16954 (Discriminant_Type (Discr)))
16957 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
16961 Find_Type (Discriminant_Type (Discr));
16962 Discr_Type := Etype (Discriminant_Type (Discr));
16964 if Error_Posted (Discriminant_Type (Discr)) then
16965 Discr_Type := Any_Type;
16969 if Is_Access_Type (Discr_Type) then
16971 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
16974 if Ada_Version < Ada_2005 then
16975 Check_Access_Discriminant_Requires_Limited
16976 (Discr, Discriminant_Type (Discr));
16979 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
16981 ("(Ada 83) access discriminant not allowed", Discr);
16984 elsif not Is_Discrete_Type (Discr_Type) then
16985 Error_Msg_N ("discriminants must have a discrete or access type",
16986 Discriminant_Type (Discr));
16989 Set_Etype (Defining_Identifier (Discr), Discr_Type);
16991 -- If a discriminant specification includes the assignment compound
16992 -- delimiter followed by an expression, the expression is the default
16993 -- expression of the discriminant; the default expression must be of
16994 -- the type of the discriminant. (RM 3.7.1) Since this expression is
16995 -- a default expression, we do the special preanalysis, since this
16996 -- expression does not freeze (see "Handling of Default and Per-
16997 -- Object Expressions" in spec of package Sem).
16999 if Present (Expression (Discr)) then
17000 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17002 if Nkind (N) = N_Formal_Type_Declaration then
17004 ("discriminant defaults not allowed for formal type",
17005 Expression (Discr));
17007 -- Flag an error for a tagged type with defaulted discriminants,
17008 -- excluding limited tagged types when compiling for Ada 2012
17009 -- (see AI05-0214).
17011 elsif Is_Tagged_Type (Current_Scope)
17012 and then (not Is_Limited_Type (Current_Scope)
17013 or else Ada_Version < Ada_2012)
17014 and then Comes_From_Source (N)
17016 -- Note: see similar test in Check_Or_Process_Discriminants, to
17017 -- handle the (illegal) case of the completion of an untagged
17018 -- view with discriminants with defaults by a tagged full view.
17019 -- We skip the check if Discr does not come from source, to
17020 -- account for the case of an untagged derived type providing
17021 -- defaults for a renamed discriminant from a private untagged
17022 -- ancestor with a tagged full view (ACATS B460006).
17024 if Ada_Version >= Ada_2012 then
17026 ("discriminants of nonlimited tagged type cannot have"
17028 Expression (Discr));
17031 ("discriminants of tagged type cannot have defaults",
17032 Expression (Discr));
17036 Default_Present := True;
17037 Append_Elmt (Expression (Discr), Elist);
17039 -- Tag the defining identifiers for the discriminants with
17040 -- their corresponding default expressions from the tree.
17042 Set_Discriminant_Default_Value
17043 (Defining_Identifier (Discr), Expression (Discr));
17047 Default_Not_Present := True;
17050 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17051 -- Discr_Type but with the null-exclusion attribute
17053 if Ada_Version >= Ada_2005 then
17055 -- Ada 2005 (AI-231): Static checks
17057 if Can_Never_Be_Null (Discr_Type) then
17058 Null_Exclusion_Static_Checks (Discr);
17060 elsif Is_Access_Type (Discr_Type)
17061 and then Null_Exclusion_Present (Discr)
17063 -- No need to check itypes because in their case this check
17064 -- was done at their point of creation
17066 and then not Is_Itype (Discr_Type)
17068 if Can_Never_Be_Null (Discr_Type) then
17070 ("`NOT NULL` not allowed (& already excludes null)",
17075 Set_Etype (Defining_Identifier (Discr),
17076 Create_Null_Excluding_Itype
17078 Related_Nod => Discr));
17080 -- Check for improper null exclusion if the type is otherwise
17081 -- legal for a discriminant.
17083 elsif Null_Exclusion_Present (Discr)
17084 and then Is_Discrete_Type (Discr_Type)
17087 ("null exclusion can only apply to an access type", Discr);
17090 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17091 -- can't have defaults. Synchronized types, or types that are
17092 -- explicitly limited are fine, but special tests apply to derived
17093 -- types in generics: in a generic body we have to assume the
17094 -- worst, and therefore defaults are not allowed if the parent is
17095 -- a generic formal private type (see ACATS B370001).
17097 if Is_Access_Type (Discr_Type) then
17098 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17099 or else not Default_Present
17100 or else Is_Limited_Record (Current_Scope)
17101 or else Is_Concurrent_Type (Current_Scope)
17102 or else Is_Concurrent_Record_Type (Current_Scope)
17103 or else Ekind (Current_Scope) = E_Limited_Private_Type
17105 if not Is_Derived_Type (Current_Scope)
17106 or else not Is_Generic_Type (Etype (Current_Scope))
17107 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17108 or else Limited_Present
17109 (Type_Definition (Parent (Current_Scope)))
17114 Error_Msg_N ("access discriminants of nonlimited types",
17115 Expression (Discr));
17116 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17119 elsif Present (Expression (Discr)) then
17121 ("(Ada 2005) access discriminants of nonlimited types",
17122 Expression (Discr));
17123 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17131 -- An element list consisting of the default expressions of the
17132 -- discriminants is constructed in the above loop and used to set
17133 -- the Discriminant_Constraint attribute for the type. If an object
17134 -- is declared of this (record or task) type without any explicit
17135 -- discriminant constraint given, this element list will form the
17136 -- actual parameters for the corresponding initialization procedure
17139 Set_Discriminant_Constraint (Current_Scope, Elist);
17140 Set_Stored_Constraint (Current_Scope, No_Elist);
17142 -- Default expressions must be provided either for all or for none
17143 -- of the discriminants of a discriminant part. (RM 3.7.1)
17145 if Default_Present and then Default_Not_Present then
17147 ("incomplete specification of defaults for discriminants", N);
17150 -- The use of the name of a discriminant is not allowed in default
17151 -- expressions of a discriminant part if the specification of the
17152 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17154 -- To detect this, the discriminant names are entered initially with an
17155 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17156 -- attempt to use a void entity (for example in an expression that is
17157 -- type-checked) produces the error message: premature usage. Now after
17158 -- completing the semantic analysis of the discriminant part, we can set
17159 -- the Ekind of all the discriminants appropriately.
17161 Discr := First (Discriminant_Specifications (N));
17162 Discr_Number := Uint_1;
17163 while Present (Discr) loop
17164 Id := Defining_Identifier (Discr);
17165 Set_Ekind (Id, E_Discriminant);
17166 Init_Component_Location (Id);
17168 Set_Discriminant_Number (Id, Discr_Number);
17170 -- Make sure this is always set, even in illegal programs
17172 Set_Corresponding_Discriminant (Id, Empty);
17174 -- Initialize the Original_Record_Component to the entity itself.
17175 -- Inherit_Components will propagate the right value to
17176 -- discriminants in derived record types.
17178 Set_Original_Record_Component (Id, Id);
17180 -- Create the discriminal for the discriminant
17182 Build_Discriminal (Id);
17185 Discr_Number := Discr_Number + 1;
17188 Set_Has_Discriminants (Current_Scope);
17189 end Process_Discriminants;
17191 -----------------------
17192 -- Process_Full_View --
17193 -----------------------
17195 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17196 Priv_Parent : Entity_Id;
17197 Full_Parent : Entity_Id;
17198 Full_Indic : Node_Id;
17200 procedure Collect_Implemented_Interfaces
17202 Ifaces : Elist_Id);
17203 -- Ada 2005: Gather all the interfaces that Typ directly or
17204 -- inherently implements. Duplicate entries are not added to
17205 -- the list Ifaces.
17207 ------------------------------------
17208 -- Collect_Implemented_Interfaces --
17209 ------------------------------------
17211 procedure Collect_Implemented_Interfaces
17216 Iface_Elmt : Elmt_Id;
17219 -- Abstract interfaces are only associated with tagged record types
17221 if not Is_Tagged_Type (Typ)
17222 or else not Is_Record_Type (Typ)
17227 -- Recursively climb to the ancestors
17229 if Etype (Typ) /= Typ
17231 -- Protect the frontend against wrong cyclic declarations like:
17233 -- type B is new A with private;
17234 -- type C is new A with private;
17236 -- type B is new C with null record;
17237 -- type C is new B with null record;
17239 and then Etype (Typ) /= Priv_T
17240 and then Etype (Typ) /= Full_T
17242 -- Keep separate the management of private type declarations
17244 if Ekind (Typ) = E_Record_Type_With_Private then
17246 -- Handle the following erroneous case:
17247 -- type Private_Type is tagged private;
17249 -- type Private_Type is new Type_Implementing_Iface;
17251 if Present (Full_View (Typ))
17252 and then Etype (Typ) /= Full_View (Typ)
17254 if Is_Interface (Etype (Typ)) then
17255 Append_Unique_Elmt (Etype (Typ), Ifaces);
17258 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17261 -- Non-private types
17264 if Is_Interface (Etype (Typ)) then
17265 Append_Unique_Elmt (Etype (Typ), Ifaces);
17268 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17272 -- Handle entities in the list of abstract interfaces
17274 if Present (Interfaces (Typ)) then
17275 Iface_Elmt := First_Elmt (Interfaces (Typ));
17276 while Present (Iface_Elmt) loop
17277 Iface := Node (Iface_Elmt);
17279 pragma Assert (Is_Interface (Iface));
17281 if not Contain_Interface (Iface, Ifaces) then
17282 Append_Elmt (Iface, Ifaces);
17283 Collect_Implemented_Interfaces (Iface, Ifaces);
17286 Next_Elmt (Iface_Elmt);
17289 end Collect_Implemented_Interfaces;
17291 -- Start of processing for Process_Full_View
17294 -- First some sanity checks that must be done after semantic
17295 -- decoration of the full view and thus cannot be placed with other
17296 -- similar checks in Find_Type_Name
17298 if not Is_Limited_Type (Priv_T)
17299 and then (Is_Limited_Type (Full_T)
17300 or else Is_Limited_Composite (Full_T))
17303 ("completion of nonlimited type cannot be limited", Full_T);
17304 Explain_Limited_Type (Full_T, Full_T);
17306 elsif Is_Abstract_Type (Full_T)
17307 and then not Is_Abstract_Type (Priv_T)
17310 ("completion of nonabstract type cannot be abstract", Full_T);
17312 elsif Is_Tagged_Type (Priv_T)
17313 and then Is_Limited_Type (Priv_T)
17314 and then not Is_Limited_Type (Full_T)
17316 -- If pragma CPP_Class was applied to the private declaration
17317 -- propagate the limitedness to the full-view
17319 if Is_CPP_Class (Priv_T) then
17320 Set_Is_Limited_Record (Full_T);
17322 -- GNAT allow its own definition of Limited_Controlled to disobey
17323 -- this rule in order in ease the implementation. The next test is
17324 -- safe because Root_Controlled is defined in a private system child
17326 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
17327 Set_Is_Limited_Composite (Full_T);
17330 ("completion of limited tagged type must be limited", Full_T);
17333 elsif Is_Generic_Type (Priv_T) then
17334 Error_Msg_N ("generic type cannot have a completion", Full_T);
17337 -- Check that ancestor interfaces of private and full views are
17338 -- consistent. We omit this check for synchronized types because
17339 -- they are performed on the corresponding record type when frozen.
17341 if Ada_Version >= Ada_2005
17342 and then Is_Tagged_Type (Priv_T)
17343 and then Is_Tagged_Type (Full_T)
17344 and then not Is_Concurrent_Type (Full_T)
17348 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17349 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17352 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17353 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17355 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17356 -- an interface type if and only if the full type is descendant
17357 -- of the interface type (AARM 7.3 (7.3/2).
17359 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17361 if Present (Iface) then
17363 ("interface & not implemented by full type " &
17364 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17367 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17369 if Present (Iface) then
17371 ("interface & not implemented by partial view " &
17372 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17377 if Is_Tagged_Type (Priv_T)
17378 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17379 and then Is_Derived_Type (Full_T)
17381 Priv_Parent := Etype (Priv_T);
17383 -- The full view of a private extension may have been transformed
17384 -- into an unconstrained derived type declaration and a subtype
17385 -- declaration (see build_derived_record_type for details).
17387 if Nkind (N) = N_Subtype_Declaration then
17388 Full_Indic := Subtype_Indication (N);
17389 Full_Parent := Etype (Base_Type (Full_T));
17391 Full_Indic := Subtype_Indication (Type_Definition (N));
17392 Full_Parent := Etype (Full_T);
17395 -- Check that the parent type of the full type is a descendant of
17396 -- the ancestor subtype given in the private extension. If either
17397 -- entity has an Etype equal to Any_Type then we had some previous
17398 -- error situation [7.3(8)].
17400 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17403 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17404 -- any order. Therefore we don't have to check that its parent must
17405 -- be a descendant of the parent of the private type declaration.
17407 elsif Is_Interface (Priv_Parent)
17408 and then Is_Interface (Full_Parent)
17412 -- Ada 2005 (AI-251): If the parent of the private type declaration
17413 -- is an interface there is no need to check that it is an ancestor
17414 -- of the associated full type declaration. The required tests for
17415 -- this case are performed by Build_Derived_Record_Type.
17417 elsif not Is_Interface (Base_Type (Priv_Parent))
17418 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17421 ("parent of full type must descend from parent"
17422 & " of private extension", Full_Indic);
17424 -- First check a formal restriction, and then proceed with checking
17425 -- Ada rules. Since the formal restriction is not a serious error, we
17426 -- don't prevent further error detection for this check, hence the
17431 -- In formal mode, when completing a private extension the type
17432 -- named in the private part must be exactly the same as that
17433 -- named in the visible part.
17435 if Priv_Parent /= Full_Parent then
17436 Error_Msg_Name_1 := Chars (Priv_Parent);
17437 Check_SPARK_Restriction ("% expected", Full_Indic);
17440 -- Check the rules of 7.3(10): if the private extension inherits
17441 -- known discriminants, then the full type must also inherit those
17442 -- discriminants from the same (ancestor) type, and the parent
17443 -- subtype of the full type must be constrained if and only if
17444 -- the ancestor subtype of the private extension is constrained.
17446 if No (Discriminant_Specifications (Parent (Priv_T)))
17447 and then not Has_Unknown_Discriminants (Priv_T)
17448 and then Has_Discriminants (Base_Type (Priv_Parent))
17451 Priv_Indic : constant Node_Id :=
17452 Subtype_Indication (Parent (Priv_T));
17454 Priv_Constr : constant Boolean :=
17455 Is_Constrained (Priv_Parent)
17457 Nkind (Priv_Indic) = N_Subtype_Indication
17459 Is_Constrained (Entity (Priv_Indic));
17461 Full_Constr : constant Boolean :=
17462 Is_Constrained (Full_Parent)
17464 Nkind (Full_Indic) = N_Subtype_Indication
17466 Is_Constrained (Entity (Full_Indic));
17468 Priv_Discr : Entity_Id;
17469 Full_Discr : Entity_Id;
17472 Priv_Discr := First_Discriminant (Priv_Parent);
17473 Full_Discr := First_Discriminant (Full_Parent);
17474 while Present (Priv_Discr) and then Present (Full_Discr) loop
17475 if Original_Record_Component (Priv_Discr) =
17476 Original_Record_Component (Full_Discr)
17478 Corresponding_Discriminant (Priv_Discr) =
17479 Corresponding_Discriminant (Full_Discr)
17486 Next_Discriminant (Priv_Discr);
17487 Next_Discriminant (Full_Discr);
17490 if Present (Priv_Discr) or else Present (Full_Discr) then
17492 ("full view must inherit discriminants of the parent"
17493 & " type used in the private extension", Full_Indic);
17495 elsif Priv_Constr and then not Full_Constr then
17497 ("parent subtype of full type must be constrained",
17500 elsif Full_Constr and then not Priv_Constr then
17502 ("parent subtype of full type must be unconstrained",
17507 -- Check the rules of 7.3(12): if a partial view has neither
17508 -- known or unknown discriminants, then the full type
17509 -- declaration shall define a definite subtype.
17511 elsif not Has_Unknown_Discriminants (Priv_T)
17512 and then not Has_Discriminants (Priv_T)
17513 and then not Is_Constrained (Full_T)
17516 ("full view must define a constrained type if partial view"
17517 & " has no discriminants", Full_T);
17520 -- ??????? Do we implement the following properly ?????
17521 -- If the ancestor subtype of a private extension has constrained
17522 -- discriminants, then the parent subtype of the full view shall
17523 -- impose a statically matching constraint on those discriminants
17528 -- For untagged types, verify that a type without discriminants
17529 -- is not completed with an unconstrained type.
17531 if not Is_Indefinite_Subtype (Priv_T)
17532 and then Is_Indefinite_Subtype (Full_T)
17534 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17538 -- AI-419: verify that the use of "limited" is consistent
17541 Orig_Decl : constant Node_Id := Original_Node (N);
17544 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17545 and then not Limited_Present (Parent (Priv_T))
17546 and then not Synchronized_Present (Parent (Priv_T))
17547 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17549 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17550 and then Limited_Present (Type_Definition (Orig_Decl))
17553 ("full view of non-limited extension cannot be limited", N);
17557 -- Ada 2005 (AI-443): A synchronized private extension must be
17558 -- completed by a task or protected type.
17560 if Ada_Version >= Ada_2005
17561 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17562 and then Synchronized_Present (Parent (Priv_T))
17563 and then not Is_Concurrent_Type (Full_T)
17565 Error_Msg_N ("full view of synchronized extension must " &
17566 "be synchronized type", N);
17569 -- Ada 2005 AI-363: if the full view has discriminants with
17570 -- defaults, it is illegal to declare constrained access subtypes
17571 -- whose designated type is the current type. This allows objects
17572 -- of the type that are declared in the heap to be unconstrained.
17574 if not Has_Unknown_Discriminants (Priv_T)
17575 and then not Has_Discriminants (Priv_T)
17576 and then Has_Discriminants (Full_T)
17578 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17580 Set_Has_Constrained_Partial_View (Full_T);
17581 Set_Has_Constrained_Partial_View (Priv_T);
17584 -- Create a full declaration for all its subtypes recorded in
17585 -- Private_Dependents and swap them similarly to the base type. These
17586 -- are subtypes that have been define before the full declaration of
17587 -- the private type. We also swap the entry in Private_Dependents list
17588 -- so we can properly restore the private view on exit from the scope.
17591 Priv_Elmt : Elmt_Id;
17596 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17597 while Present (Priv_Elmt) loop
17598 Priv := Node (Priv_Elmt);
17600 if Ekind_In (Priv, E_Private_Subtype,
17601 E_Limited_Private_Subtype,
17602 E_Record_Subtype_With_Private)
17604 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17605 Set_Is_Itype (Full);
17606 Set_Parent (Full, Parent (Priv));
17607 Set_Associated_Node_For_Itype (Full, N);
17609 -- Now we need to complete the private subtype, but since the
17610 -- base type has already been swapped, we must also swap the
17611 -- subtypes (and thus, reverse the arguments in the call to
17612 -- Complete_Private_Subtype).
17614 Copy_And_Swap (Priv, Full);
17615 Complete_Private_Subtype (Full, Priv, Full_T, N);
17616 Replace_Elmt (Priv_Elmt, Full);
17619 Next_Elmt (Priv_Elmt);
17623 -- If the private view was tagged, copy the new primitive operations
17624 -- from the private view to the full view.
17626 if Is_Tagged_Type (Full_T) then
17628 Disp_Typ : Entity_Id;
17629 Full_List : Elist_Id;
17631 Prim_Elmt : Elmt_Id;
17632 Priv_List : Elist_Id;
17636 L : Elist_Id) return Boolean;
17637 -- Determine whether list L contains element E
17645 L : Elist_Id) return Boolean
17647 List_Elmt : Elmt_Id;
17650 List_Elmt := First_Elmt (L);
17651 while Present (List_Elmt) loop
17652 if Node (List_Elmt) = E then
17656 Next_Elmt (List_Elmt);
17662 -- Start of processing
17665 if Is_Tagged_Type (Priv_T) then
17666 Priv_List := Primitive_Operations (Priv_T);
17667 Prim_Elmt := First_Elmt (Priv_List);
17669 -- In the case of a concurrent type completing a private tagged
17670 -- type, primitives may have been declared in between the two
17671 -- views. These subprograms need to be wrapped the same way
17672 -- entries and protected procedures are handled because they
17673 -- cannot be directly shared by the two views.
17675 if Is_Concurrent_Type (Full_T) then
17677 Conc_Typ : constant Entity_Id :=
17678 Corresponding_Record_Type (Full_T);
17679 Curr_Nod : Node_Id := Parent (Conc_Typ);
17680 Wrap_Spec : Node_Id;
17683 while Present (Prim_Elmt) loop
17684 Prim := Node (Prim_Elmt);
17686 if Comes_From_Source (Prim)
17687 and then not Is_Abstract_Subprogram (Prim)
17690 Make_Subprogram_Declaration (Sloc (Prim),
17694 Obj_Typ => Conc_Typ,
17696 Parameter_Specifications (
17699 Insert_After (Curr_Nod, Wrap_Spec);
17700 Curr_Nod := Wrap_Spec;
17702 Analyze (Wrap_Spec);
17705 Next_Elmt (Prim_Elmt);
17711 -- For non-concurrent types, transfer explicit primitives, but
17712 -- omit those inherited from the parent of the private view
17713 -- since they will be re-inherited later on.
17716 Full_List := Primitive_Operations (Full_T);
17718 while Present (Prim_Elmt) loop
17719 Prim := Node (Prim_Elmt);
17721 if Comes_From_Source (Prim)
17722 and then not Contains (Prim, Full_List)
17724 Append_Elmt (Prim, Full_List);
17727 Next_Elmt (Prim_Elmt);
17731 -- Untagged private view
17734 Full_List := Primitive_Operations (Full_T);
17736 -- In this case the partial view is untagged, so here we locate
17737 -- all of the earlier primitives that need to be treated as
17738 -- dispatching (those that appear between the two views). Note
17739 -- that these additional operations must all be new operations
17740 -- (any earlier operations that override inherited operations
17741 -- of the full view will already have been inserted in the
17742 -- primitives list, marked by Check_Operation_From_Private_View
17743 -- as dispatching. Note that implicit "/=" operators are
17744 -- excluded from being added to the primitives list since they
17745 -- shouldn't be treated as dispatching (tagged "/=" is handled
17748 Prim := Next_Entity (Full_T);
17749 while Present (Prim) and then Prim /= Priv_T loop
17750 if Ekind_In (Prim, E_Procedure, E_Function) then
17751 Disp_Typ := Find_Dispatching_Type (Prim);
17753 if Disp_Typ = Full_T
17754 and then (Chars (Prim) /= Name_Op_Ne
17755 or else Comes_From_Source (Prim))
17757 Check_Controlling_Formals (Full_T, Prim);
17759 if not Is_Dispatching_Operation (Prim) then
17760 Append_Elmt (Prim, Full_List);
17761 Set_Is_Dispatching_Operation (Prim, True);
17762 Set_DT_Position (Prim, No_Uint);
17765 elsif Is_Dispatching_Operation (Prim)
17766 and then Disp_Typ /= Full_T
17769 -- Verify that it is not otherwise controlled by a
17770 -- formal or a return value of type T.
17772 Check_Controlling_Formals (Disp_Typ, Prim);
17776 Next_Entity (Prim);
17780 -- For the tagged case, the two views can share the same primitive
17781 -- operations list and the same class-wide type. Update attributes
17782 -- of the class-wide type which depend on the full declaration.
17784 if Is_Tagged_Type (Priv_T) then
17785 Set_Direct_Primitive_Operations (Priv_T, Full_List);
17786 Set_Class_Wide_Type
17787 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
17789 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
17794 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
17796 if Known_To_Have_Preelab_Init (Priv_T) then
17798 -- Case where there is a pragma Preelaborable_Initialization. We
17799 -- always allow this in predefined units, which is a bit of a kludge,
17800 -- but it means we don't have to struggle to meet the requirements in
17801 -- the RM for having Preelaborable Initialization. Otherwise we
17802 -- require that the type meets the RM rules. But we can't check that
17803 -- yet, because of the rule about overriding Initialize, so we simply
17804 -- set a flag that will be checked at freeze time.
17806 if not In_Predefined_Unit (Full_T) then
17807 Set_Must_Have_Preelab_Init (Full_T);
17811 -- If pragma CPP_Class was applied to the private type declaration,
17812 -- propagate it now to the full type declaration.
17814 if Is_CPP_Class (Priv_T) then
17815 Set_Is_CPP_Class (Full_T);
17816 Set_Convention (Full_T, Convention_CPP);
17819 -- If the private view has user specified stream attributes, then so has
17822 -- Why the test, how could these flags be already set in Full_T ???
17824 if Has_Specified_Stream_Read (Priv_T) then
17825 Set_Has_Specified_Stream_Read (Full_T);
17828 if Has_Specified_Stream_Write (Priv_T) then
17829 Set_Has_Specified_Stream_Write (Full_T);
17832 if Has_Specified_Stream_Input (Priv_T) then
17833 Set_Has_Specified_Stream_Input (Full_T);
17836 if Has_Specified_Stream_Output (Priv_T) then
17837 Set_Has_Specified_Stream_Output (Full_T);
17840 -- Propagate invariants to full type
17842 if Has_Invariants (Priv_T) then
17843 Set_Has_Invariants (Full_T);
17844 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
17847 if Has_Inheritable_Invariants (Priv_T) then
17848 Set_Has_Inheritable_Invariants (Full_T);
17851 -- Propagate predicates to full type
17853 if Has_Predicates (Priv_T) then
17854 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
17855 Set_Has_Predicates (Priv_T);
17857 end Process_Full_View;
17859 -----------------------------------
17860 -- Process_Incomplete_Dependents --
17861 -----------------------------------
17863 procedure Process_Incomplete_Dependents
17865 Full_T : Entity_Id;
17868 Inc_Elmt : Elmt_Id;
17869 Priv_Dep : Entity_Id;
17870 New_Subt : Entity_Id;
17872 Disc_Constraint : Elist_Id;
17875 if No (Private_Dependents (Inc_T)) then
17879 -- Itypes that may be generated by the completion of an incomplete
17880 -- subtype are not used by the back-end and not attached to the tree.
17881 -- They are created only for constraint-checking purposes.
17883 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
17884 while Present (Inc_Elmt) loop
17885 Priv_Dep := Node (Inc_Elmt);
17887 if Ekind (Priv_Dep) = E_Subprogram_Type then
17889 -- An Access_To_Subprogram type may have a return type or a
17890 -- parameter type that is incomplete. Replace with the full view.
17892 if Etype (Priv_Dep) = Inc_T then
17893 Set_Etype (Priv_Dep, Full_T);
17897 Formal : Entity_Id;
17900 Formal := First_Formal (Priv_Dep);
17901 while Present (Formal) loop
17902 if Etype (Formal) = Inc_T then
17903 Set_Etype (Formal, Full_T);
17906 Next_Formal (Formal);
17910 elsif Is_Overloadable (Priv_Dep) then
17912 -- If a subprogram in the incomplete dependents list is primitive
17913 -- for a tagged full type then mark it as a dispatching operation,
17914 -- check whether it overrides an inherited subprogram, and check
17915 -- restrictions on its controlling formals. Note that a protected
17916 -- operation is never dispatching: only its wrapper operation
17917 -- (which has convention Ada) is.
17919 if Is_Tagged_Type (Full_T)
17920 and then Is_Primitive (Priv_Dep)
17921 and then Convention (Priv_Dep) /= Convention_Protected
17923 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
17924 Set_Is_Dispatching_Operation (Priv_Dep);
17925 Check_Controlling_Formals (Full_T, Priv_Dep);
17928 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
17930 -- Can happen during processing of a body before the completion
17931 -- of a TA type. Ignore, because spec is also on dependent list.
17935 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
17936 -- corresponding subtype of the full view.
17938 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
17939 Set_Subtype_Indication
17940 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
17941 Set_Etype (Priv_Dep, Full_T);
17942 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
17943 Set_Analyzed (Parent (Priv_Dep), False);
17945 -- Reanalyze the declaration, suppressing the call to
17946 -- Enter_Name to avoid duplicate names.
17948 Analyze_Subtype_Declaration
17949 (N => Parent (Priv_Dep),
17952 -- Dependent is a subtype
17955 -- We build a new subtype indication using the full view of the
17956 -- incomplete parent. The discriminant constraints have been
17957 -- elaborated already at the point of the subtype declaration.
17959 New_Subt := Create_Itype (E_Void, N);
17961 if Has_Discriminants (Full_T) then
17962 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
17964 Disc_Constraint := No_Elist;
17967 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
17968 Set_Full_View (Priv_Dep, New_Subt);
17971 Next_Elmt (Inc_Elmt);
17973 end Process_Incomplete_Dependents;
17975 --------------------------------
17976 -- Process_Range_Expr_In_Decl --
17977 --------------------------------
17979 procedure Process_Range_Expr_In_Decl
17982 Check_List : List_Id := Empty_List;
17983 R_Check_Off : Boolean := False;
17984 In_Iter_Schm : Boolean := False)
17987 R_Checks : Check_Result;
17988 Insert_Node : Node_Id;
17989 Def_Id : Entity_Id;
17992 Analyze_And_Resolve (R, Base_Type (T));
17994 if Nkind (R) = N_Range then
17996 -- In SPARK, all ranges should be static, with the exception of the
17997 -- discrete type definition of a loop parameter specification.
17999 if not In_Iter_Schm
18000 and then not Is_Static_Range (R)
18002 Check_SPARK_Restriction ("range should be static", R);
18005 Lo := Low_Bound (R);
18006 Hi := High_Bound (R);
18008 -- We need to ensure validity of the bounds here, because if we
18009 -- go ahead and do the expansion, then the expanded code will get
18010 -- analyzed with range checks suppressed and we miss the check.
18012 Validity_Check_Range (R);
18014 -- If there were errors in the declaration, try and patch up some
18015 -- common mistakes in the bounds. The cases handled are literals
18016 -- which are Integer where the expected type is Real and vice versa.
18017 -- These corrections allow the compilation process to proceed further
18018 -- along since some basic assumptions of the format of the bounds
18021 if Etype (R) = Any_Type then
18023 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18025 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18027 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18029 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18031 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18033 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18035 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18037 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18044 -- If the bounds of the range have been mistakenly given as string
18045 -- literals (perhaps in place of character literals), then an error
18046 -- has already been reported, but we rewrite the string literal as a
18047 -- bound of the range's type to avoid blowups in later processing
18048 -- that looks at static values.
18050 if Nkind (Lo) = N_String_Literal then
18052 Make_Attribute_Reference (Sloc (Lo),
18053 Attribute_Name => Name_First,
18054 Prefix => New_Reference_To (T, Sloc (Lo))));
18055 Analyze_And_Resolve (Lo);
18058 if Nkind (Hi) = N_String_Literal then
18060 Make_Attribute_Reference (Sloc (Hi),
18061 Attribute_Name => Name_First,
18062 Prefix => New_Reference_To (T, Sloc (Hi))));
18063 Analyze_And_Resolve (Hi);
18066 -- If bounds aren't scalar at this point then exit, avoiding
18067 -- problems with further processing of the range in this procedure.
18069 if not Is_Scalar_Type (Etype (Lo)) then
18073 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18074 -- then range of the base type. Here we check whether the bounds
18075 -- are in the range of the subtype itself. Note that if the bounds
18076 -- represent the null range the Constraint_Error exception should
18079 -- ??? The following code should be cleaned up as follows
18081 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18082 -- is done in the call to Range_Check (R, T); below
18084 -- 2. The use of R_Check_Off should be investigated and possibly
18085 -- removed, this would clean up things a bit.
18087 if Is_Null_Range (Lo, Hi) then
18091 -- Capture values of bounds and generate temporaries for them
18092 -- if needed, before applying checks, since checks may cause
18093 -- duplication of the expression without forcing evaluation.
18095 if Expander_Active then
18096 Force_Evaluation (Lo);
18097 Force_Evaluation (Hi);
18100 -- We use a flag here instead of suppressing checks on the
18101 -- type because the type we check against isn't necessarily
18102 -- the place where we put the check.
18104 if not R_Check_Off then
18105 R_Checks := Get_Range_Checks (R, T);
18107 -- Look up tree to find an appropriate insertion point. We
18108 -- can't just use insert_actions because later processing
18109 -- depends on the insertion node. Prior to Ada2012 the
18110 -- insertion point could only be a declaration or a loop, but
18111 -- quantified expressions can appear within any context in an
18112 -- expression, and the insertion point can be any statement,
18113 -- pragma, or declaration.
18115 Insert_Node := Parent (R);
18116 while Present (Insert_Node) loop
18118 Nkind (Insert_Node) in N_Declaration
18121 (Insert_Node, N_Component_Declaration,
18122 N_Loop_Parameter_Specification,
18123 N_Function_Specification,
18124 N_Procedure_Specification);
18126 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18127 or else Nkind (Insert_Node) in
18128 N_Statement_Other_Than_Procedure_Call
18129 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18132 Insert_Node := Parent (Insert_Node);
18135 -- Why would Type_Decl not be present??? Without this test,
18136 -- short regression tests fail.
18138 if Present (Insert_Node) then
18140 -- Case of loop statement. Verify that the range is part
18141 -- of the subtype indication of the iteration scheme.
18143 if Nkind (Insert_Node) = N_Loop_Statement then
18148 Indic := Parent (R);
18149 while Present (Indic)
18150 and then Nkind (Indic) /= N_Subtype_Indication
18152 Indic := Parent (Indic);
18155 if Present (Indic) then
18156 Def_Id := Etype (Subtype_Mark (Indic));
18158 Insert_Range_Checks
18162 Sloc (Insert_Node),
18164 Do_Before => True);
18168 -- Insertion before a declaration. If the declaration
18169 -- includes discriminants, the list of applicable checks
18170 -- is given by the caller.
18172 elsif Nkind (Insert_Node) in N_Declaration then
18173 Def_Id := Defining_Identifier (Insert_Node);
18175 if (Ekind (Def_Id) = E_Record_Type
18176 and then Depends_On_Discriminant (R))
18178 (Ekind (Def_Id) = E_Protected_Type
18179 and then Has_Discriminants (Def_Id))
18181 Append_Range_Checks
18183 Check_List, Def_Id, Sloc (Insert_Node), R);
18186 Insert_Range_Checks
18188 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18192 -- Insertion before a statement. Range appears in the
18193 -- context of a quantified expression. Insertion will
18194 -- take place when expression is expanded.
18203 -- Case of other than an explicit N_Range node
18205 elsif Expander_Active then
18206 Get_Index_Bounds (R, Lo, Hi);
18207 Force_Evaluation (Lo);
18208 Force_Evaluation (Hi);
18210 end Process_Range_Expr_In_Decl;
18212 --------------------------------------
18213 -- Process_Real_Range_Specification --
18214 --------------------------------------
18216 procedure Process_Real_Range_Specification (Def : Node_Id) is
18217 Spec : constant Node_Id := Real_Range_Specification (Def);
18220 Err : Boolean := False;
18222 procedure Analyze_Bound (N : Node_Id);
18223 -- Analyze and check one bound
18225 -------------------
18226 -- Analyze_Bound --
18227 -------------------
18229 procedure Analyze_Bound (N : Node_Id) is
18231 Analyze_And_Resolve (N, Any_Real);
18233 if not Is_OK_Static_Expression (N) then
18234 Flag_Non_Static_Expr
18235 ("bound in real type definition is not static!", N);
18240 -- Start of processing for Process_Real_Range_Specification
18243 if Present (Spec) then
18244 Lo := Low_Bound (Spec);
18245 Hi := High_Bound (Spec);
18246 Analyze_Bound (Lo);
18247 Analyze_Bound (Hi);
18249 -- If error, clear away junk range specification
18252 Set_Real_Range_Specification (Def, Empty);
18255 end Process_Real_Range_Specification;
18257 ---------------------
18258 -- Process_Subtype --
18259 ---------------------
18261 function Process_Subtype
18263 Related_Nod : Node_Id;
18264 Related_Id : Entity_Id := Empty;
18265 Suffix : Character := ' ') return Entity_Id
18268 Def_Id : Entity_Id;
18269 Error_Node : Node_Id;
18270 Full_View_Id : Entity_Id;
18271 Subtype_Mark_Id : Entity_Id;
18273 May_Have_Null_Exclusion : Boolean;
18275 procedure Check_Incomplete (T : Entity_Id);
18276 -- Called to verify that an incomplete type is not used prematurely
18278 ----------------------
18279 -- Check_Incomplete --
18280 ----------------------
18282 procedure Check_Incomplete (T : Entity_Id) is
18284 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18286 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18288 not (Ada_Version >= Ada_2005
18290 (Nkind (Parent (T)) = N_Subtype_Declaration
18292 (Nkind (Parent (T)) = N_Subtype_Indication
18293 and then Nkind (Parent (Parent (T))) =
18294 N_Subtype_Declaration)))
18296 Error_Msg_N ("invalid use of type before its full declaration", T);
18298 end Check_Incomplete;
18300 -- Start of processing for Process_Subtype
18303 -- Case of no constraints present
18305 if Nkind (S) /= N_Subtype_Indication then
18307 Check_Incomplete (S);
18310 -- Ada 2005 (AI-231): Static check
18312 if Ada_Version >= Ada_2005
18313 and then Present (P)
18314 and then Null_Exclusion_Present (P)
18315 and then Nkind (P) /= N_Access_To_Object_Definition
18316 and then not Is_Access_Type (Entity (S))
18318 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18321 -- The following is ugly, can't we have a range or even a flag???
18323 May_Have_Null_Exclusion :=
18324 Nkind_In (P, N_Access_Definition,
18325 N_Access_Function_Definition,
18326 N_Access_Procedure_Definition,
18327 N_Access_To_Object_Definition,
18329 N_Component_Definition)
18331 Nkind_In (P, N_Derived_Type_Definition,
18332 N_Discriminant_Specification,
18333 N_Formal_Object_Declaration,
18334 N_Object_Declaration,
18335 N_Object_Renaming_Declaration,
18336 N_Parameter_Specification,
18337 N_Subtype_Declaration);
18339 -- Create an Itype that is a duplicate of Entity (S) but with the
18340 -- null-exclusion attribute.
18342 if May_Have_Null_Exclusion
18343 and then Is_Access_Type (Entity (S))
18344 and then Null_Exclusion_Present (P)
18346 -- No need to check the case of an access to object definition.
18347 -- It is correct to define double not-null pointers.
18350 -- type Not_Null_Int_Ptr is not null access Integer;
18351 -- type Acc is not null access Not_Null_Int_Ptr;
18353 and then Nkind (P) /= N_Access_To_Object_Definition
18355 if Can_Never_Be_Null (Entity (S)) then
18356 case Nkind (Related_Nod) is
18357 when N_Full_Type_Declaration =>
18358 if Nkind (Type_Definition (Related_Nod))
18359 in N_Array_Type_Definition
18363 (Component_Definition
18364 (Type_Definition (Related_Nod)));
18367 Subtype_Indication (Type_Definition (Related_Nod));
18370 when N_Subtype_Declaration =>
18371 Error_Node := Subtype_Indication (Related_Nod);
18373 when N_Object_Declaration =>
18374 Error_Node := Object_Definition (Related_Nod);
18376 when N_Component_Declaration =>
18378 Subtype_Indication (Component_Definition (Related_Nod));
18380 when N_Allocator =>
18381 Error_Node := Expression (Related_Nod);
18384 pragma Assert (False);
18385 Error_Node := Related_Nod;
18389 ("`NOT NULL` not allowed (& already excludes null)",
18395 Create_Null_Excluding_Itype
18397 Related_Nod => P));
18398 Set_Entity (S, Etype (S));
18403 -- Case of constraint present, so that we have an N_Subtype_Indication
18404 -- node (this node is created only if constraints are present).
18407 Find_Type (Subtype_Mark (S));
18409 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18411 (Nkind (Parent (S)) = N_Subtype_Declaration
18412 and then Is_Itype (Defining_Identifier (Parent (S))))
18414 Check_Incomplete (Subtype_Mark (S));
18418 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18420 -- Explicit subtype declaration case
18422 if Nkind (P) = N_Subtype_Declaration then
18423 Def_Id := Defining_Identifier (P);
18425 -- Explicit derived type definition case
18427 elsif Nkind (P) = N_Derived_Type_Definition then
18428 Def_Id := Defining_Identifier (Parent (P));
18430 -- Implicit case, the Def_Id must be created as an implicit type.
18431 -- The one exception arises in the case of concurrent types, array
18432 -- and access types, where other subsidiary implicit types may be
18433 -- created and must appear before the main implicit type. In these
18434 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18435 -- has not yet been called to create Def_Id.
18438 if Is_Array_Type (Subtype_Mark_Id)
18439 or else Is_Concurrent_Type (Subtype_Mark_Id)
18440 or else Is_Access_Type (Subtype_Mark_Id)
18444 -- For the other cases, we create a new unattached Itype,
18445 -- and set the indication to ensure it gets attached later.
18449 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18453 -- If the kind of constraint is invalid for this kind of type,
18454 -- then give an error, and then pretend no constraint was given.
18456 if not Is_Valid_Constraint_Kind
18457 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18460 ("incorrect constraint for this kind of type", Constraint (S));
18462 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18464 -- Set Ekind of orphan itype, to prevent cascaded errors
18466 if Present (Def_Id) then
18467 Set_Ekind (Def_Id, Ekind (Any_Type));
18470 -- Make recursive call, having got rid of the bogus constraint
18472 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18475 -- Remaining processing depends on type
18477 case Ekind (Subtype_Mark_Id) is
18478 when Access_Kind =>
18479 Constrain_Access (Def_Id, S, Related_Nod);
18482 and then Is_Itype (Designated_Type (Def_Id))
18483 and then Nkind (Related_Nod) = N_Subtype_Declaration
18484 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18486 Build_Itype_Reference
18487 (Designated_Type (Def_Id), Related_Nod);
18491 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18493 when Decimal_Fixed_Point_Kind =>
18494 Constrain_Decimal (Def_Id, S);
18496 when Enumeration_Kind =>
18497 Constrain_Enumeration (Def_Id, S);
18499 when Ordinary_Fixed_Point_Kind =>
18500 Constrain_Ordinary_Fixed (Def_Id, S);
18503 Constrain_Float (Def_Id, S);
18505 when Integer_Kind =>
18506 Constrain_Integer (Def_Id, S);
18508 when E_Record_Type |
18511 E_Incomplete_Type =>
18512 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18514 if Ekind (Def_Id) = E_Incomplete_Type then
18515 Set_Private_Dependents (Def_Id, New_Elmt_List);
18518 when Private_Kind =>
18519 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18520 Set_Private_Dependents (Def_Id, New_Elmt_List);
18522 -- In case of an invalid constraint prevent further processing
18523 -- since the type constructed is missing expected fields.
18525 if Etype (Def_Id) = Any_Type then
18529 -- If the full view is that of a task with discriminants,
18530 -- we must constrain both the concurrent type and its
18531 -- corresponding record type. Otherwise we will just propagate
18532 -- the constraint to the full view, if available.
18534 if Present (Full_View (Subtype_Mark_Id))
18535 and then Has_Discriminants (Subtype_Mark_Id)
18536 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18539 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18541 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18542 Constrain_Concurrent (Full_View_Id, S,
18543 Related_Nod, Related_Id, Suffix);
18544 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18545 Set_Full_View (Def_Id, Full_View_Id);
18547 -- Introduce an explicit reference to the private subtype,
18548 -- to prevent scope anomalies in gigi if first use appears
18549 -- in a nested context, e.g. a later function body.
18550 -- Should this be generated in other contexts than a full
18551 -- type declaration?
18553 if Is_Itype (Def_Id)
18555 Nkind (Parent (P)) = N_Full_Type_Declaration
18557 Build_Itype_Reference (Def_Id, Parent (P));
18561 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18564 when Concurrent_Kind =>
18565 Constrain_Concurrent (Def_Id, S,
18566 Related_Nod, Related_Id, Suffix);
18569 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18572 -- Size and Convention are always inherited from the base type
18574 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18575 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18579 end Process_Subtype;
18581 ---------------------------------------
18582 -- Check_Anonymous_Access_Components --
18583 ---------------------------------------
18585 procedure Check_Anonymous_Access_Components
18586 (Typ_Decl : Node_Id;
18589 Comp_List : Node_Id)
18591 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18592 Anon_Access : Entity_Id;
18595 Comp_Def : Node_Id;
18597 Type_Def : Node_Id;
18599 procedure Build_Incomplete_Type_Declaration;
18600 -- If the record type contains components that include an access to the
18601 -- current record, then create an incomplete type declaration for the
18602 -- record, to be used as the designated type of the anonymous access.
18603 -- This is done only once, and only if there is no previous partial
18604 -- view of the type.
18606 function Designates_T (Subt : Node_Id) return Boolean;
18607 -- Check whether a node designates the enclosing record type, or 'Class
18610 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18611 -- Check whether an access definition includes a reference to
18612 -- the enclosing record type. The reference can be a subtype mark
18613 -- in the access definition itself, a 'Class attribute reference, or
18614 -- recursively a reference appearing in a parameter specification
18615 -- or result definition of an access_to_subprogram definition.
18617 --------------------------------------
18618 -- Build_Incomplete_Type_Declaration --
18619 --------------------------------------
18621 procedure Build_Incomplete_Type_Declaration is
18626 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18627 -- it's "is new ... with record" or else "is tagged record ...".
18629 Is_Tagged : constant Boolean :=
18630 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18633 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18635 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18636 and then Tagged_Present (Type_Definition (Typ_Decl)));
18639 -- If there is a previous partial view, no need to create a new one
18640 -- If the partial view, given by Prev, is incomplete, If Prev is
18641 -- a private declaration, full declaration is flagged accordingly.
18643 if Prev /= Typ then
18645 Make_Class_Wide_Type (Prev);
18646 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18647 Set_Etype (Class_Wide_Type (Typ), Typ);
18652 elsif Has_Private_Declaration (Typ) then
18654 -- If we refer to T'Class inside T, and T is the completion of a
18655 -- private type, then we need to make sure the class-wide type
18659 Make_Class_Wide_Type (Typ);
18664 -- If there was a previous anonymous access type, the incomplete
18665 -- type declaration will have been created already.
18667 elsif Present (Current_Entity (Typ))
18668 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18669 and then Full_View (Current_Entity (Typ)) = Typ
18672 and then Comes_From_Source (Current_Entity (Typ))
18673 and then not Is_Tagged_Type (Current_Entity (Typ))
18675 Make_Class_Wide_Type (Typ);
18677 ("incomplete view of tagged type should be declared tagged?",
18678 Parent (Current_Entity (Typ)));
18683 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18684 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18686 -- Type has already been inserted into the current scope. Remove
18687 -- it, and add incomplete declaration for type, so that subsequent
18688 -- anonymous access types can use it. The entity is unchained from
18689 -- the homonym list and from immediate visibility. After analysis,
18690 -- the entity in the incomplete declaration becomes immediately
18691 -- visible in the record declaration that follows.
18693 H := Current_Entity (Typ);
18696 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18699 and then Homonym (H) /= Typ
18701 H := Homonym (Typ);
18704 Set_Homonym (H, Homonym (Typ));
18707 Insert_Before (Typ_Decl, Decl);
18709 Set_Full_View (Inc_T, Typ);
18713 -- Create a common class-wide type for both views, and set the
18714 -- Etype of the class-wide type to the full view.
18716 Make_Class_Wide_Type (Inc_T);
18717 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
18718 Set_Etype (Class_Wide_Type (Typ), Typ);
18721 end Build_Incomplete_Type_Declaration;
18727 function Designates_T (Subt : Node_Id) return Boolean is
18728 Type_Id : constant Name_Id := Chars (Typ);
18730 function Names_T (Nam : Node_Id) return Boolean;
18731 -- The record type has not been introduced in the current scope
18732 -- yet, so we must examine the name of the type itself, either
18733 -- an identifier T, or an expanded name of the form P.T, where
18734 -- P denotes the current scope.
18740 function Names_T (Nam : Node_Id) return Boolean is
18742 if Nkind (Nam) = N_Identifier then
18743 return Chars (Nam) = Type_Id;
18745 elsif Nkind (Nam) = N_Selected_Component then
18746 if Chars (Selector_Name (Nam)) = Type_Id then
18747 if Nkind (Prefix (Nam)) = N_Identifier then
18748 return Chars (Prefix (Nam)) = Chars (Current_Scope);
18750 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
18751 return Chars (Selector_Name (Prefix (Nam))) =
18752 Chars (Current_Scope);
18766 -- Start of processing for Designates_T
18769 if Nkind (Subt) = N_Identifier then
18770 return Chars (Subt) = Type_Id;
18772 -- Reference can be through an expanded name which has not been
18773 -- analyzed yet, and which designates enclosing scopes.
18775 elsif Nkind (Subt) = N_Selected_Component then
18776 if Names_T (Subt) then
18779 -- Otherwise it must denote an entity that is already visible.
18780 -- The access definition may name a subtype of the enclosing
18781 -- type, if there is a previous incomplete declaration for it.
18784 Find_Selected_Component (Subt);
18786 Is_Entity_Name (Subt)
18787 and then Scope (Entity (Subt)) = Current_Scope
18789 (Chars (Base_Type (Entity (Subt))) = Type_Id
18791 (Is_Class_Wide_Type (Entity (Subt))
18793 Chars (Etype (Base_Type (Entity (Subt)))) =
18797 -- A reference to the current type may appear as the prefix of
18798 -- a 'Class attribute.
18800 elsif Nkind (Subt) = N_Attribute_Reference
18801 and then Attribute_Name (Subt) = Name_Class
18803 return Names_T (Prefix (Subt));
18814 function Mentions_T (Acc_Def : Node_Id) return Boolean is
18815 Param_Spec : Node_Id;
18817 Acc_Subprg : constant Node_Id :=
18818 Access_To_Subprogram_Definition (Acc_Def);
18821 if No (Acc_Subprg) then
18822 return Designates_T (Subtype_Mark (Acc_Def));
18825 -- Component is an access_to_subprogram: examine its formals,
18826 -- and result definition in the case of an access_to_function.
18828 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
18829 while Present (Param_Spec) loop
18830 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
18831 and then Mentions_T (Parameter_Type (Param_Spec))
18835 elsif Designates_T (Parameter_Type (Param_Spec)) then
18842 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
18843 if Nkind (Result_Definition (Acc_Subprg)) =
18844 N_Access_Definition
18846 return Mentions_T (Result_Definition (Acc_Subprg));
18848 return Designates_T (Result_Definition (Acc_Subprg));
18855 -- Start of processing for Check_Anonymous_Access_Components
18858 if No (Comp_List) then
18862 Comp := First (Component_Items (Comp_List));
18863 while Present (Comp) loop
18864 if Nkind (Comp) = N_Component_Declaration
18866 (Access_Definition (Component_Definition (Comp)))
18868 Mentions_T (Access_Definition (Component_Definition (Comp)))
18870 Comp_Def := Component_Definition (Comp);
18872 Access_To_Subprogram_Definition
18873 (Access_Definition (Comp_Def));
18875 Build_Incomplete_Type_Declaration;
18876 Anon_Access := Make_Temporary (Loc, 'S');
18878 -- Create a declaration for the anonymous access type: either
18879 -- an access_to_object or an access_to_subprogram.
18881 if Present (Acc_Def) then
18882 if Nkind (Acc_Def) = N_Access_Function_Definition then
18884 Make_Access_Function_Definition (Loc,
18885 Parameter_Specifications =>
18886 Parameter_Specifications (Acc_Def),
18887 Result_Definition => Result_Definition (Acc_Def));
18890 Make_Access_Procedure_Definition (Loc,
18891 Parameter_Specifications =>
18892 Parameter_Specifications (Acc_Def));
18897 Make_Access_To_Object_Definition (Loc,
18898 Subtype_Indication =>
18901 (Access_Definition (Comp_Def))));
18903 Set_Constant_Present
18904 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
18906 (Type_Def, All_Present (Access_Definition (Comp_Def)));
18909 Set_Null_Exclusion_Present
18911 Null_Exclusion_Present (Access_Definition (Comp_Def)));
18914 Make_Full_Type_Declaration (Loc,
18915 Defining_Identifier => Anon_Access,
18916 Type_Definition => Type_Def);
18918 Insert_Before (Typ_Decl, Decl);
18921 -- If an access to subprogram, create the extra formals
18923 if Present (Acc_Def) then
18924 Create_Extra_Formals (Designated_Type (Anon_Access));
18926 -- If an access to object, preserve entity of designated type,
18927 -- for ASIS use, before rewriting the component definition.
18934 Desig := Entity (Subtype_Indication (Type_Def));
18936 -- If the access definition is to the current record,
18937 -- the visible entity at this point is an incomplete
18938 -- type. Retrieve the full view to simplify ASIS queries
18940 if Ekind (Desig) = E_Incomplete_Type then
18941 Desig := Full_View (Desig);
18945 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
18950 Make_Component_Definition (Loc,
18951 Subtype_Indication =>
18952 New_Occurrence_Of (Anon_Access, Loc)));
18954 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
18955 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
18957 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
18960 Set_Is_Local_Anonymous_Access (Anon_Access);
18966 if Present (Variant_Part (Comp_List)) then
18970 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
18971 while Present (V) loop
18972 Check_Anonymous_Access_Components
18973 (Typ_Decl, Typ, Prev, Component_List (V));
18974 Next_Non_Pragma (V);
18978 end Check_Anonymous_Access_Components;
18980 --------------------------------
18981 -- Preanalyze_Spec_Expression --
18982 --------------------------------
18984 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18985 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18987 In_Spec_Expression := True;
18988 Preanalyze_And_Resolve (N, T);
18989 In_Spec_Expression := Save_In_Spec_Expression;
18990 end Preanalyze_Spec_Expression;
18992 -----------------------------
18993 -- Record_Type_Declaration --
18994 -----------------------------
18996 procedure Record_Type_Declaration
19001 Def : constant Node_Id := Type_Definition (N);
19002 Is_Tagged : Boolean;
19003 Tag_Comp : Entity_Id;
19006 -- These flags must be initialized before calling Process_Discriminants
19007 -- because this routine makes use of them.
19009 Set_Ekind (T, E_Record_Type);
19011 Init_Size_Align (T);
19012 Set_Interfaces (T, No_Elist);
19013 Set_Stored_Constraint (T, No_Elist);
19017 if Ada_Version < Ada_2005
19018 or else not Interface_Present (Def)
19020 if Limited_Present (Def) then
19021 Check_SPARK_Restriction ("limited is not allowed", N);
19024 if Abstract_Present (Def) then
19025 Check_SPARK_Restriction ("abstract is not allowed", N);
19028 -- The flag Is_Tagged_Type might have already been set by
19029 -- Find_Type_Name if it detected an error for declaration T. This
19030 -- arises in the case of private tagged types where the full view
19031 -- omits the word tagged.
19034 Tagged_Present (Def)
19035 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19037 Set_Is_Tagged_Type (T, Is_Tagged);
19038 Set_Is_Limited_Record (T, Limited_Present (Def));
19040 -- Type is abstract if full declaration carries keyword, or if
19041 -- previous partial view did.
19043 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19044 or else Abstract_Present (Def));
19047 Check_SPARK_Restriction ("interface is not allowed", N);
19050 Analyze_Interface_Declaration (T, Def);
19052 if Present (Discriminant_Specifications (N)) then
19054 ("interface types cannot have discriminants",
19055 Defining_Identifier
19056 (First (Discriminant_Specifications (N))));
19060 -- First pass: if there are self-referential access components,
19061 -- create the required anonymous access type declarations, and if
19062 -- need be an incomplete type declaration for T itself.
19064 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19066 if Ada_Version >= Ada_2005
19067 and then Present (Interface_List (Def))
19069 Check_Interfaces (N, Def);
19072 Ifaces_List : Elist_Id;
19075 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19076 -- already in the parents.
19080 Ifaces_List => Ifaces_List,
19081 Exclude_Parents => True);
19083 Set_Interfaces (T, Ifaces_List);
19087 -- Records constitute a scope for the component declarations within.
19088 -- The scope is created prior to the processing of these declarations.
19089 -- Discriminants are processed first, so that they are visible when
19090 -- processing the other components. The Ekind of the record type itself
19091 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19093 -- Enter record scope
19097 -- If an incomplete or private type declaration was already given for
19098 -- the type, then this scope already exists, and the discriminants have
19099 -- been declared within. We must verify that the full declaration
19100 -- matches the incomplete one.
19102 Check_Or_Process_Discriminants (N, T, Prev);
19104 Set_Is_Constrained (T, not Has_Discriminants (T));
19105 Set_Has_Delayed_Freeze (T, True);
19107 -- For tagged types add a manually analyzed component corresponding
19108 -- to the component _tag, the corresponding piece of tree will be
19109 -- expanded as part of the freezing actions if it is not a CPP_Class.
19113 -- Do not add the tag unless we are in expansion mode
19115 if Expander_Active then
19116 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19117 Enter_Name (Tag_Comp);
19119 Set_Ekind (Tag_Comp, E_Component);
19120 Set_Is_Tag (Tag_Comp);
19121 Set_Is_Aliased (Tag_Comp);
19122 Set_Etype (Tag_Comp, RTE (RE_Tag));
19123 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19124 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19125 Init_Component_Location (Tag_Comp);
19127 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19128 -- implemented interfaces.
19130 if Has_Interfaces (T) then
19131 Add_Interface_Tag_Components (N, T);
19135 Make_Class_Wide_Type (T);
19136 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19139 -- We must suppress range checks when processing record components in
19140 -- the presence of discriminants, since we don't want spurious checks to
19141 -- be generated during their analysis, but Suppress_Range_Checks flags
19142 -- must be reset the after processing the record definition.
19144 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19145 -- couldn't we just use the normal range check suppression method here.
19146 -- That would seem cleaner ???
19148 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19149 Set_Kill_Range_Checks (T, True);
19150 Record_Type_Definition (Def, Prev);
19151 Set_Kill_Range_Checks (T, False);
19153 Record_Type_Definition (Def, Prev);
19156 -- Exit from record scope
19160 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19161 -- the implemented interfaces and associate them an aliased entity.
19164 and then not Is_Empty_List (Interface_List (Def))
19166 Derive_Progenitor_Subprograms (T, T);
19168 end Record_Type_Declaration;
19170 ----------------------------
19171 -- Record_Type_Definition --
19172 ----------------------------
19174 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19175 Component : Entity_Id;
19176 Ctrl_Components : Boolean := False;
19177 Final_Storage_Only : Boolean;
19181 if Ekind (Prev_T) = E_Incomplete_Type then
19182 T := Full_View (Prev_T);
19187 -- In SPARK, tagged types and type extensions may only be declared in
19188 -- the specification of library unit packages.
19190 if Present (Def) and then Is_Tagged_Type (T) then
19196 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19197 Typ := Parent (Def);
19200 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19201 Typ := Parent (Parent (Def));
19204 Ctxt := Parent (Typ);
19206 if Nkind (Ctxt) = N_Package_Body
19207 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19209 Check_SPARK_Restriction
19210 ("type should be defined in package specification", Typ);
19212 elsif Nkind (Ctxt) /= N_Package_Specification
19213 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19215 Check_SPARK_Restriction
19216 ("type should be defined in library unit package", Typ);
19221 Final_Storage_Only := not Is_Controlled (T);
19223 -- Ada 2005: check whether an explicit Limited is present in a derived
19224 -- type declaration.
19226 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19227 and then Limited_Present (Parent (Def))
19229 Set_Is_Limited_Record (T);
19232 -- If the component list of a record type is defined by the reserved
19233 -- word null and there is no discriminant part, then the record type has
19234 -- no components and all records of the type are null records (RM 3.7)
19235 -- This procedure is also called to process the extension part of a
19236 -- record extension, in which case the current scope may have inherited
19240 or else No (Component_List (Def))
19241 or else Null_Present (Component_List (Def))
19243 if not Is_Tagged_Type (T) then
19244 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19248 Analyze_Declarations (Component_Items (Component_List (Def)));
19250 if Present (Variant_Part (Component_List (Def))) then
19251 Check_SPARK_Restriction ("variant part is not allowed", Def);
19252 Analyze (Variant_Part (Component_List (Def)));
19256 -- After completing the semantic analysis of the record definition,
19257 -- record components, both new and inherited, are accessible. Set their
19258 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19259 -- whose Ekind may be void.
19261 Component := First_Entity (Current_Scope);
19262 while Present (Component) loop
19263 if Ekind (Component) = E_Void
19264 and then not Is_Itype (Component)
19266 Set_Ekind (Component, E_Component);
19267 Init_Component_Location (Component);
19270 if Has_Task (Etype (Component)) then
19274 if Ekind (Component) /= E_Component then
19277 -- Do not set Has_Controlled_Component on a class-wide equivalent
19278 -- type. See Make_CW_Equivalent_Type.
19280 elsif not Is_Class_Wide_Equivalent_Type (T)
19281 and then (Has_Controlled_Component (Etype (Component))
19282 or else (Chars (Component) /= Name_uParent
19283 and then Is_Controlled (Etype (Component))))
19285 Set_Has_Controlled_Component (T, True);
19286 Final_Storage_Only :=
19288 and then Finalize_Storage_Only (Etype (Component));
19289 Ctrl_Components := True;
19292 Next_Entity (Component);
19295 -- A Type is Finalize_Storage_Only only if all its controlled components
19298 if Ctrl_Components then
19299 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19302 -- Place reference to end record on the proper entity, which may
19303 -- be a partial view.
19305 if Present (Def) then
19306 Process_End_Label (Def, 'e', Prev_T);
19308 end Record_Type_Definition;
19310 ------------------------
19311 -- Replace_Components --
19312 ------------------------
19314 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19315 function Process (N : Node_Id) return Traverse_Result;
19321 function Process (N : Node_Id) return Traverse_Result is
19325 if Nkind (N) = N_Discriminant_Specification then
19326 Comp := First_Discriminant (Typ);
19327 while Present (Comp) loop
19328 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19329 Set_Defining_Identifier (N, Comp);
19333 Next_Discriminant (Comp);
19336 elsif Nkind (N) = N_Component_Declaration then
19337 Comp := First_Component (Typ);
19338 while Present (Comp) loop
19339 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19340 Set_Defining_Identifier (N, Comp);
19344 Next_Component (Comp);
19351 procedure Replace is new Traverse_Proc (Process);
19353 -- Start of processing for Replace_Components
19357 end Replace_Components;
19359 -------------------------------
19360 -- Set_Completion_Referenced --
19361 -------------------------------
19363 procedure Set_Completion_Referenced (E : Entity_Id) is
19365 -- If in main unit, mark entity that is a completion as referenced,
19366 -- warnings go on the partial view when needed.
19368 if In_Extended_Main_Source_Unit (E) then
19369 Set_Referenced (E);
19371 end Set_Completion_Referenced;
19373 ---------------------
19374 -- Set_Fixed_Range --
19375 ---------------------
19377 -- The range for fixed-point types is complicated by the fact that we
19378 -- do not know the exact end points at the time of the declaration. This
19379 -- is true for three reasons:
19381 -- A size clause may affect the fudging of the end-points
19382 -- A small clause may affect the values of the end-points
19383 -- We try to include the end-points if it does not affect the size
19385 -- This means that the actual end-points must be established at the point
19386 -- when the type is frozen. Meanwhile, we first narrow the range as
19387 -- permitted (so that it will fit if necessary in a small specified size),
19388 -- and then build a range subtree with these narrowed bounds.
19390 -- Set_Fixed_Range constructs the range from real literal values, and sets
19391 -- the range as the Scalar_Range of the given fixed-point type entity.
19393 -- The parent of this range is set to point to the entity so that it is
19394 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19395 -- other scalar types, which are just pointers to the range in the
19396 -- original tree, this would otherwise be an orphan).
19398 -- The tree is left unanalyzed. When the type is frozen, the processing
19399 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19400 -- analyzed, and uses this as an indication that it should complete
19401 -- work on the range (it will know the final small and size values).
19403 procedure Set_Fixed_Range
19409 S : constant Node_Id :=
19411 Low_Bound => Make_Real_Literal (Loc, Lo),
19412 High_Bound => Make_Real_Literal (Loc, Hi));
19414 Set_Scalar_Range (E, S);
19416 end Set_Fixed_Range;
19418 ----------------------------------
19419 -- Set_Scalar_Range_For_Subtype --
19420 ----------------------------------
19422 procedure Set_Scalar_Range_For_Subtype
19423 (Def_Id : Entity_Id;
19427 Kind : constant Entity_Kind := Ekind (Def_Id);
19430 -- Defend against previous error
19432 if Nkind (R) = N_Error then
19436 Set_Scalar_Range (Def_Id, R);
19438 -- We need to link the range into the tree before resolving it so
19439 -- that types that are referenced, including importantly the subtype
19440 -- itself, are properly frozen (Freeze_Expression requires that the
19441 -- expression be properly linked into the tree). Of course if it is
19442 -- already linked in, then we do not disturb the current link.
19444 if No (Parent (R)) then
19445 Set_Parent (R, Def_Id);
19448 -- Reset the kind of the subtype during analysis of the range, to
19449 -- catch possible premature use in the bounds themselves.
19451 Set_Ekind (Def_Id, E_Void);
19452 Process_Range_Expr_In_Decl (R, Subt);
19453 Set_Ekind (Def_Id, Kind);
19455 -- In ALFA, all subtypes should have a static range
19457 if Nkind (R) = N_Range
19458 and then not Is_Static_Range (R)
19460 Set_Is_In_ALFA (Def_Id, False);
19462 end Set_Scalar_Range_For_Subtype;
19464 --------------------------------------------------------
19465 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19466 --------------------------------------------------------
19468 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19472 -- Make sure set if encountered during Expand_To_Stored_Constraint
19474 Set_Stored_Constraint (E, No_Elist);
19476 -- Give it the right value
19478 if Is_Constrained (E) and then Has_Discriminants (E) then
19479 Set_Stored_Constraint (E,
19480 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19482 end Set_Stored_Constraint_From_Discriminant_Constraint;
19484 -------------------------------------
19485 -- Signed_Integer_Type_Declaration --
19486 -------------------------------------
19488 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19489 Implicit_Base : Entity_Id;
19490 Base_Typ : Entity_Id;
19493 Errs : Boolean := False;
19497 function Can_Derive_From (E : Entity_Id) return Boolean;
19498 -- Determine whether given bounds allow derivation from specified type
19500 procedure Check_Bound (Expr : Node_Id);
19501 -- Check bound to make sure it is integral and static. If not, post
19502 -- appropriate error message and set Errs flag
19504 ---------------------
19505 -- Can_Derive_From --
19506 ---------------------
19508 -- Note we check both bounds against both end values, to deal with
19509 -- strange types like ones with a range of 0 .. -12341234.
19511 function Can_Derive_From (E : Entity_Id) return Boolean is
19512 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19513 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19515 return Lo <= Lo_Val and then Lo_Val <= Hi
19517 Lo <= Hi_Val and then Hi_Val <= Hi;
19518 end Can_Derive_From;
19524 procedure Check_Bound (Expr : Node_Id) is
19526 -- If a range constraint is used as an integer type definition, each
19527 -- bound of the range must be defined by a static expression of some
19528 -- integer type, but the two bounds need not have the same integer
19529 -- type (Negative bounds are allowed.) (RM 3.5.4)
19531 if not Is_Integer_Type (Etype (Expr)) then
19533 ("integer type definition bounds must be of integer type", Expr);
19536 elsif not Is_OK_Static_Expression (Expr) then
19537 Flag_Non_Static_Expr
19538 ("non-static expression used for integer type bound!", Expr);
19541 -- The bounds are folded into literals, and we set their type to be
19542 -- universal, to avoid typing difficulties: we cannot set the type
19543 -- of the literal to the new type, because this would be a forward
19544 -- reference for the back end, and if the original type is user-
19545 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19548 if Is_Entity_Name (Expr) then
19549 Fold_Uint (Expr, Expr_Value (Expr), True);
19552 Set_Etype (Expr, Universal_Integer);
19556 -- Start of processing for Signed_Integer_Type_Declaration
19559 -- Create an anonymous base type
19562 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19564 -- Analyze and check the bounds, they can be of any integer type
19566 Lo := Low_Bound (Def);
19567 Hi := High_Bound (Def);
19569 -- Arbitrarily use Integer as the type if either bound had an error
19571 if Hi = Error or else Lo = Error then
19572 Base_Typ := Any_Integer;
19573 Set_Error_Posted (T, True);
19575 -- Here both bounds are OK expressions
19578 Analyze_And_Resolve (Lo, Any_Integer);
19579 Analyze_And_Resolve (Hi, Any_Integer);
19585 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19586 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19589 -- Find type to derive from
19591 Lo_Val := Expr_Value (Lo);
19592 Hi_Val := Expr_Value (Hi);
19594 if Can_Derive_From (Standard_Short_Short_Integer) then
19595 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19597 elsif Can_Derive_From (Standard_Short_Integer) then
19598 Base_Typ := Base_Type (Standard_Short_Integer);
19600 elsif Can_Derive_From (Standard_Integer) then
19601 Base_Typ := Base_Type (Standard_Integer);
19603 elsif Can_Derive_From (Standard_Long_Integer) then
19604 Base_Typ := Base_Type (Standard_Long_Integer);
19606 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19607 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19610 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19611 Error_Msg_N ("integer type definition bounds out of range", Def);
19612 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19613 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19617 -- Complete both implicit base and declared first subtype entities
19619 Set_Etype (Implicit_Base, Base_Typ);
19620 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19621 Set_Size_Info (Implicit_Base, (Base_Typ));
19622 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19623 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19625 Set_Ekind (T, E_Signed_Integer_Subtype);
19626 Set_Etype (T, Implicit_Base);
19628 Set_Size_Info (T, (Implicit_Base));
19629 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19630 Set_Scalar_Range (T, Def);
19631 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19632 Set_Is_Constrained (T);
19633 Set_Is_In_ALFA (T);
19634 end Signed_Integer_Type_Declaration;