1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Itypes; use Itypes;
43 with Layout; use Layout;
45 with Lib.Xref; use Lib.Xref;
46 with Namet; use Namet;
47 with Nmake; use Nmake;
49 with Restrict; use Restrict;
50 with Rident; use Rident;
51 with Rtsfind; use Rtsfind;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Case; use Sem_Case;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch7; use Sem_Ch7;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Ch10; use Sem_Ch10;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Dim; use Sem_Dim;
62 with Sem_Disp; use Sem_Disp;
63 with Sem_Dist; use Sem_Dist;
64 with Sem_Elim; use Sem_Elim;
65 with Sem_Eval; use Sem_Eval;
66 with Sem_Mech; use Sem_Mech;
67 with Sem_Prag; use Sem_Prag;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
95 -- Analyze all delayed pragmas chained on the contract of object Obj_Id as
96 -- if they appeared at the end of the declarative region. The pragmas to be
104 procedure Build_Derived_Type
106 Parent_Type : Entity_Id;
107 Derived_Type : Entity_Id;
108 Is_Completion : Boolean;
109 Derive_Subps : Boolean := True);
110 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
111 -- the N_Full_Type_Declaration node containing the derived type definition.
112 -- Parent_Type is the entity for the parent type in the derived type
113 -- definition and Derived_Type the actual derived type. Is_Completion must
114 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
115 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
116 -- completion of a private type declaration. If Is_Completion is set to
117 -- True, N is the completion of a private type declaration and Derived_Type
118 -- is different from the defining identifier inside N (i.e. Derived_Type /=
119 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
120 -- subprograms should be derived. The only case where this parameter is
121 -- False is when Build_Derived_Type is recursively called to process an
122 -- implicit derived full type for a type derived from a private type (in
123 -- that case the subprograms must only be derived for the private view of
126 -- ??? These flags need a bit of re-examination and re-documentation:
127 -- ??? are they both necessary (both seem related to the recursion)?
129 procedure Build_Derived_Access_Type
131 Parent_Type : Entity_Id;
132 Derived_Type : Entity_Id);
133 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
134 -- create an implicit base if the parent type is constrained or if the
135 -- subtype indication has a constraint.
137 procedure Build_Derived_Array_Type
139 Parent_Type : Entity_Id;
140 Derived_Type : Entity_Id);
141 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
142 -- create an implicit base if the parent type is constrained or if the
143 -- subtype indication has a constraint.
145 procedure Build_Derived_Concurrent_Type
147 Parent_Type : Entity_Id;
148 Derived_Type : Entity_Id);
149 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
150 -- protected type, inherit entries and protected subprograms, check
151 -- legality of discriminant constraints if any.
153 procedure Build_Derived_Enumeration_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id);
157 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
158 -- type, we must create a new list of literals. Types derived from
159 -- Character and [Wide_]Wide_Character are special-cased.
161 procedure Build_Derived_Numeric_Type
163 Parent_Type : Entity_Id;
164 Derived_Type : Entity_Id);
165 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
166 -- an anonymous base type, and propagate constraint to subtype if needed.
168 procedure Build_Derived_Private_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Is_Completion : Boolean;
173 Derive_Subps : Boolean := True);
174 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
175 -- because the parent may or may not have a completion, and the derivation
176 -- may itself be a completion.
178 procedure Build_Derived_Record_Type
180 Parent_Type : Entity_Id;
181 Derived_Type : Entity_Id;
182 Derive_Subps : Boolean := True);
183 -- Subsidiary procedure used for tagged and untagged record types
184 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
185 -- All parameters are as in Build_Derived_Type except that N, in
186 -- addition to being an N_Full_Type_Declaration node, can also be an
187 -- N_Private_Extension_Declaration node. See the definition of this routine
188 -- for much more info. Derive_Subps indicates whether subprograms should be
189 -- derived from the parent type. The only case where Derive_Subps is False
190 -- is for an implicit derived full type for a type derived from a private
191 -- type (see Build_Derived_Type).
193 procedure Build_Discriminal (Discrim : Entity_Id);
194 -- Create the discriminal corresponding to discriminant Discrim, that is
195 -- the parameter corresponding to Discrim to be used in initialization
196 -- procedures for the type where Discrim is a discriminant. Discriminals
197 -- are not used during semantic analysis, and are not fully defined
198 -- entities until expansion. Thus they are not given a scope until
199 -- initialization procedures are built.
201 function Build_Discriminant_Constraints
204 Derived_Def : Boolean := False) return Elist_Id;
205 -- Validate discriminant constraints and return the list of the constraints
206 -- in order of discriminant declarations, where T is the discriminated
207 -- unconstrained type. Def is the N_Subtype_Indication node where the
208 -- discriminants constraints for T are specified. Derived_Def is True
209 -- when building the discriminant constraints in a derived type definition
210 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
211 -- type and Def is the constraint "(xxx)" on T and this routine sets the
212 -- Corresponding_Discriminant field of the discriminants in the derived
213 -- type D to point to the corresponding discriminants in the parent type T.
215 procedure Build_Discriminated_Subtype
219 Related_Nod : Node_Id;
220 For_Access : Boolean := False);
221 -- Subsidiary procedure to Constrain_Discriminated_Type and to
222 -- Process_Incomplete_Dependents. Given
224 -- T (a possibly discriminated base type)
225 -- Def_Id (a very partially built subtype for T),
227 -- the call completes Def_Id to be the appropriate E_*_Subtype.
229 -- The Elist is the list of discriminant constraints if any (it is set
230 -- to No_Elist if T is not a discriminated type, and to an empty list if
231 -- T has discriminants but there are no discriminant constraints). The
232 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
233 -- The For_Access says whether or not this subtype is really constraining
234 -- an access type. That is its sole purpose is the designated type of an
235 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
236 -- is built to avoid freezing T when the access subtype is frozen.
238 function Build_Scalar_Bound
241 Der_T : Entity_Id) return Node_Id;
242 -- The bounds of a derived scalar type are conversions of the bounds of
243 -- the parent type. Optimize the representation if the bounds are literals.
244 -- Needs a more complete spec--what are the parameters exactly, and what
245 -- exactly is the returned value, and how is Bound affected???
247 procedure Build_Underlying_Full_View
251 -- If the completion of a private type is itself derived from a private
252 -- type, or if the full view of a private subtype is itself private, the
253 -- back-end has no way to compute the actual size of this type. We build
254 -- an internal subtype declaration of the proper parent type to convey
255 -- this information. This extra mechanism is needed because a full
256 -- view cannot itself have a full view (it would get clobbered during
259 procedure Check_Access_Discriminant_Requires_Limited
262 -- Check the restriction that the type to which an access discriminant
263 -- belongs must be a concurrent type or a descendant of a type with
264 -- the reserved word 'limited' in its declaration.
266 procedure Check_Anonymous_Access_Components
270 Comp_List : Node_Id);
271 -- Ada 2005 AI-382: an access component in a record definition can refer to
272 -- the enclosing record, in which case it denotes the type itself, and not
273 -- the current instance of the type. We create an anonymous access type for
274 -- the component, and flag it as an access to a component, so accessibility
275 -- checks are properly performed on it. The declaration of the access type
276 -- is placed ahead of that of the record to prevent order-of-elaboration
277 -- circularity issues in Gigi. We create an incomplete type for the record
278 -- declaration, which is the designated type of the anonymous access.
280 procedure Check_Delta_Expression (E : Node_Id);
281 -- Check that the expression represented by E is suitable for use as a
282 -- delta expression, i.e. it is of real type and is static.
284 procedure Check_Digits_Expression (E : Node_Id);
285 -- Check that the expression represented by E is suitable for use as a
286 -- digits expression, i.e. it is of integer type, positive and static.
288 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
289 -- Validate the initialization of an object declaration. T is the required
290 -- type, and Exp is the initialization expression.
292 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
293 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
295 procedure Check_Or_Process_Discriminants
298 Prev : Entity_Id := Empty);
299 -- If N is the full declaration of the completion T of an incomplete or
300 -- private type, check its discriminants (which are already known to be
301 -- conformant with those of the partial view, see Find_Type_Name),
302 -- otherwise process them. Prev is the entity of the partial declaration,
305 procedure Check_Real_Bound (Bound : Node_Id);
306 -- Check given bound for being of real type and static. If not, post an
307 -- appropriate message, and rewrite the bound with the real literal zero.
309 procedure Constant_Redeclaration
313 -- Various checks on legality of full declaration of deferred constant.
314 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
315 -- node. The caller has not yet set any attributes of this entity.
317 function Contain_Interface
319 Ifaces : Elist_Id) return Boolean;
320 -- Ada 2005: Determine whether Iface is present in the list Ifaces
322 procedure Convert_Scalar_Bounds
324 Parent_Type : Entity_Id;
325 Derived_Type : Entity_Id;
327 -- For derived scalar types, convert the bounds in the type definition to
328 -- the derived type, and complete their analysis. Given a constraint of the
329 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
330 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
331 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
332 -- subtype are conversions of those bounds to the derived_type, so that
333 -- their typing is consistent.
335 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
336 -- Copies attributes from array base type T2 to array base type T1. Copies
337 -- only attributes that apply to base types, but not subtypes.
339 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
340 -- Copies attributes from array subtype T2 to array subtype T1. Copies
341 -- attributes that apply to both subtypes and base types.
343 procedure Create_Constrained_Components
347 Constraints : Elist_Id);
348 -- Build the list of entities for a constrained discriminated record
349 -- subtype. If a component depends on a discriminant, replace its subtype
350 -- using the discriminant values in the discriminant constraint. Subt
351 -- is the defining identifier for the subtype whose list of constrained
352 -- entities we will create. Decl_Node is the type declaration node where
353 -- we will attach all the itypes created. Typ is the base discriminated
354 -- type for the subtype Subt. Constraints is the list of discriminant
355 -- constraints for Typ.
357 function Constrain_Component_Type
359 Constrained_Typ : Entity_Id;
360 Related_Node : Node_Id;
362 Constraints : Elist_Id) return Entity_Id;
363 -- Given a discriminated base type Typ, a list of discriminant constraints,
364 -- Constraints, for Typ and a component Comp of Typ, create and return the
365 -- type corresponding to Etype (Comp) where all discriminant references
366 -- are replaced with the corresponding constraint. If Etype (Comp) contains
367 -- no discriminant references then it is returned as-is. Constrained_Typ
368 -- is the final constrained subtype to which the constrained component
369 -- belongs. Related_Node is the node where we attach all created itypes.
371 procedure Constrain_Access
372 (Def_Id : in out Entity_Id;
374 Related_Nod : Node_Id);
375 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
376 -- an anonymous type created for a subtype indication. In that case it is
377 -- created in the procedure and attached to Related_Nod.
379 procedure Constrain_Array
380 (Def_Id : in out Entity_Id;
382 Related_Nod : Node_Id;
383 Related_Id : Entity_Id;
385 -- Apply a list of index constraints to an unconstrained array type. The
386 -- first parameter is the entity for the resulting subtype. A value of
387 -- Empty for Def_Id indicates that an implicit type must be created, but
388 -- creation is delayed (and must be done by this procedure) because other
389 -- subsidiary implicit types must be created first (which is why Def_Id
390 -- is an in/out parameter). The second parameter is a subtype indication
391 -- node for the constrained array to be created (e.g. something of the
392 -- form string (1 .. 10)). Related_Nod gives the place where this type
393 -- has to be inserted in the tree. The Related_Id and Suffix parameters
394 -- are used to build the associated Implicit type name.
396 procedure Constrain_Concurrent
397 (Def_Id : in out Entity_Id;
399 Related_Nod : Node_Id;
400 Related_Id : Entity_Id;
402 -- Apply list of discriminant constraints to an unconstrained concurrent
405 -- SI is the N_Subtype_Indication node containing the constraint and
406 -- the unconstrained type to constrain.
408 -- Def_Id is the entity for the resulting constrained subtype. A value
409 -- of Empty for Def_Id indicates that an implicit type must be created,
410 -- but creation is delayed (and must be done by this procedure) because
411 -- other subsidiary implicit types must be created first (which is why
412 -- Def_Id is an in/out parameter).
414 -- Related_Nod gives the place where this type has to be inserted
417 -- The last two arguments are used to create its external name if needed.
419 function Constrain_Corresponding_Record
420 (Prot_Subt : Entity_Id;
421 Corr_Rec : Entity_Id;
422 Related_Nod : Node_Id) return Entity_Id;
423 -- When constraining a protected type or task type with discriminants,
424 -- constrain the corresponding record with the same discriminant values.
426 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
427 -- Constrain a decimal fixed point type with a digits constraint and/or a
428 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
430 procedure Constrain_Discriminated_Type
433 Related_Nod : Node_Id;
434 For_Access : Boolean := False);
435 -- Process discriminant constraints of composite type. Verify that values
436 -- have been provided for all discriminants, that the original type is
437 -- unconstrained, and that the types of the supplied expressions match
438 -- the discriminant types. The first three parameters are like in routine
439 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
442 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
443 -- Constrain an enumeration type with a range constraint. This is identical
444 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
446 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
447 -- Constrain a floating point type with either a digits constraint
448 -- and/or a range constraint, building a E_Floating_Point_Subtype.
450 procedure Constrain_Index
453 Related_Nod : Node_Id;
454 Related_Id : Entity_Id;
457 -- Process an index constraint S in a constrained array declaration. The
458 -- constraint can be a subtype name, or a range with or without an explicit
459 -- subtype mark. The index is the corresponding index of the unconstrained
460 -- array. The Related_Id and Suffix parameters are used to build the
461 -- associated Implicit type name.
463 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
464 -- Build subtype of a signed or modular integer type
466 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
467 -- Constrain an ordinary fixed point type with a range constraint, and
468 -- build an E_Ordinary_Fixed_Point_Subtype entity.
470 procedure Copy_And_Swap (Priv, Full : Entity_Id);
471 -- Copy the Priv entity into the entity of its full declaration then swap
472 -- the two entities in such a manner that the former private type is now
473 -- seen as a full type.
475 procedure Decimal_Fixed_Point_Type_Declaration
478 -- Create a new decimal fixed point type, and apply the constraint to
479 -- obtain a subtype of this new type.
481 procedure Complete_Private_Subtype
484 Full_Base : Entity_Id;
485 Related_Nod : Node_Id);
486 -- Complete the implicit full view of a private subtype by setting the
487 -- appropriate semantic fields. If the full view of the parent is a record
488 -- type, build constrained components of subtype.
490 procedure Derive_Progenitor_Subprograms
491 (Parent_Type : Entity_Id;
492 Tagged_Type : Entity_Id);
493 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
494 -- operations of progenitors of Tagged_Type, and replace the subsidiary
495 -- subtypes with Tagged_Type, to build the specs of the inherited interface
496 -- primitives. The derived primitives are aliased to those of the
497 -- interface. This routine takes care also of transferring to the full view
498 -- subprograms associated with the partial view of Tagged_Type that cover
499 -- interface primitives.
501 procedure Derived_Standard_Character
503 Parent_Type : Entity_Id;
504 Derived_Type : Entity_Id);
505 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
506 -- derivations from types Standard.Character and Standard.Wide_Character.
508 procedure Derived_Type_Declaration
511 Is_Completion : Boolean);
512 -- Process a derived type declaration. Build_Derived_Type is invoked
513 -- to process the actual derived type definition. Parameters N and
514 -- Is_Completion have the same meaning as in Build_Derived_Type.
515 -- T is the N_Defining_Identifier for the entity defined in the
516 -- N_Full_Type_Declaration node N, that is T is the derived type.
518 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
519 -- Insert each literal in symbol table, as an overloadable identifier. Each
520 -- enumeration type is mapped into a sequence of integers, and each literal
521 -- is defined as a constant with integer value. If any of the literals are
522 -- character literals, the type is a character type, which means that
523 -- strings are legal aggregates for arrays of components of the type.
525 function Expand_To_Stored_Constraint
527 Constraint : Elist_Id) return Elist_Id;
528 -- Given a constraint (i.e. a list of expressions) on the discriminants of
529 -- Typ, expand it into a constraint on the stored discriminants and return
530 -- the new list of expressions constraining the stored discriminants.
532 function Find_Type_Of_Object
534 Related_Nod : Node_Id) return Entity_Id;
535 -- Get type entity for object referenced by Obj_Def, attaching the
536 -- implicit types generated to Related_Nod
538 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
539 -- Create a new float and apply the constraint to obtain subtype of it
541 function Has_Range_Constraint (N : Node_Id) return Boolean;
542 -- Given an N_Subtype_Indication node N, return True if a range constraint
543 -- is present, either directly, or as part of a digits or delta constraint.
544 -- In addition, a digits constraint in the decimal case returns True, since
545 -- it establishes a default range if no explicit range is present.
547 function Inherit_Components
549 Parent_Base : Entity_Id;
550 Derived_Base : Entity_Id;
552 Inherit_Discr : Boolean;
553 Discs : Elist_Id) return Elist_Id;
554 -- Called from Build_Derived_Record_Type to inherit the components of
555 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
556 -- For more information on derived types and component inheritance please
557 -- consult the comment above the body of Build_Derived_Record_Type.
559 -- N is the original derived type declaration
561 -- Is_Tagged is set if we are dealing with tagged types
563 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
564 -- Parent_Base, otherwise no discriminants are inherited.
566 -- Discs gives the list of constraints that apply to Parent_Base in the
567 -- derived type declaration. If Discs is set to No_Elist, then we have
568 -- the following situation:
570 -- type Parent (D1..Dn : ..) is [tagged] record ...;
571 -- type Derived is new Parent [with ...];
573 -- which gets treated as
575 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
577 -- For untagged types the returned value is an association list. The list
578 -- starts from the association (Parent_Base => Derived_Base), and then it
579 -- contains a sequence of the associations of the form
581 -- (Old_Component => New_Component),
583 -- where Old_Component is the Entity_Id of a component in Parent_Base and
584 -- New_Component is the Entity_Id of the corresponding component in
585 -- Derived_Base. For untagged records, this association list is needed when
586 -- copying the record declaration for the derived base. In the tagged case
587 -- the value returned is irrelevant.
589 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
590 -- Propagate static and dynamic predicate flags from a parent to the
591 -- subtype in a subtype declaration with and without constraints.
593 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
594 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
595 -- Determine whether subprogram Subp is a procedure subject to pragma
596 -- Extensions_Visible with value False and has at least one controlling
597 -- parameter of mode OUT.
599 function Is_Valid_Constraint_Kind
601 Constraint_Kind : Node_Kind) return Boolean;
602 -- Returns True if it is legal to apply the given kind of constraint to the
603 -- given kind of type (index constraint to an array type, for example).
605 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
606 -- Create new modular type. Verify that modulus is in bounds
608 procedure New_Concatenation_Op (Typ : Entity_Id);
609 -- Create an abbreviated declaration for an operator in order to
610 -- materialize concatenation on array types.
612 procedure Ordinary_Fixed_Point_Type_Declaration
615 -- Create a new ordinary fixed point type, and apply the constraint to
616 -- obtain subtype of it.
618 procedure Prepare_Private_Subtype_Completion
620 Related_Nod : Node_Id);
621 -- Id is a subtype of some private type. Creates the full declaration
622 -- associated with Id whenever possible, i.e. when the full declaration
623 -- of the base type is already known. Records each subtype into
624 -- Private_Dependents of the base type.
626 procedure Process_Incomplete_Dependents
630 -- Process all entities that depend on an incomplete type. There include
631 -- subtypes, subprogram types that mention the incomplete type in their
632 -- profiles, and subprogram with access parameters that designate the
635 -- Inc_T is the defining identifier of an incomplete type declaration, its
636 -- Ekind is E_Incomplete_Type.
638 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
640 -- Full_T is N's defining identifier.
642 -- Subtypes of incomplete types with discriminants are completed when the
643 -- parent type is. This is simpler than private subtypes, because they can
644 -- only appear in the same scope, and there is no need to exchange views.
645 -- Similarly, access_to_subprogram types may have a parameter or a return
646 -- type that is an incomplete type, and that must be replaced with the
649 -- If the full type is tagged, subprogram with access parameters that
650 -- designated the incomplete may be primitive operations of the full type,
651 -- and have to be processed accordingly.
653 procedure Process_Real_Range_Specification (Def : Node_Id);
654 -- Given the type definition for a real type, this procedure processes and
655 -- checks the real range specification of this type definition if one is
656 -- present. If errors are found, error messages are posted, and the
657 -- Real_Range_Specification of Def is reset to Empty.
659 procedure Propagate_Default_Init_Cond_Attributes
660 (From_Typ : Entity_Id;
662 Parent_To_Derivation : Boolean := False;
663 Private_To_Full_View : Boolean := False);
664 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
665 -- all attributes related to pragma Default_Initial_Condition from From_Typ
666 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
667 -- the creation of a derived type. Flag Private_To_Full_View should be set
668 -- when processing both views of a private type.
670 procedure Record_Type_Declaration
674 -- Process a record type declaration (for both untagged and tagged
675 -- records). Parameters T and N are exactly like in procedure
676 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
677 -- for this routine. If this is the completion of an incomplete type
678 -- declaration, Prev is the entity of the incomplete declaration, used for
679 -- cross-referencing. Otherwise Prev = T.
681 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
682 -- This routine is used to process the actual record type definition (both
683 -- for untagged and tagged records). Def is a record type definition node.
684 -- This procedure analyzes the components in this record type definition.
685 -- Prev_T is the entity for the enclosing record type. It is provided so
686 -- that its Has_Task flag can be set if any of the component have Has_Task
687 -- set. If the declaration is the completion of an incomplete type
688 -- declaration, Prev_T is the original incomplete type, whose full view is
691 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
692 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
693 -- build a copy of the declaration tree of the parent, and we create
694 -- independently the list of components for the derived type. Semantic
695 -- information uses the component entities, but record representation
696 -- clauses are validated on the declaration tree. This procedure replaces
697 -- discriminants and components in the declaration with those that have
698 -- been created by Inherit_Components.
700 procedure Set_Fixed_Range
705 -- Build a range node with the given bounds and set it as the Scalar_Range
706 -- of the given fixed-point type entity. Loc is the source location used
707 -- for the constructed range. See body for further details.
709 procedure Set_Scalar_Range_For_Subtype
713 -- This routine is used to set the scalar range field for a subtype given
714 -- Def_Id, the entity for the subtype, and R, the range expression for the
715 -- scalar range. Subt provides the parent subtype to be used to analyze,
716 -- resolve, and check the given range.
718 procedure Set_Default_SSO (T : Entity_Id);
719 -- T is the entity for an array or record being declared. This procedure
720 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
721 -- to the setting of Opt.Default_SSO.
723 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
724 -- Create a new signed integer entity, and apply the constraint to obtain
725 -- the required first named subtype of this type.
727 procedure Set_Stored_Constraint_From_Discriminant_Constraint
729 -- E is some record type. This routine computes E's Stored_Constraint
730 -- from its Discriminant_Constraint.
732 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
733 -- Check that an entity in a list of progenitors is an interface,
734 -- emit error otherwise.
736 -----------------------
737 -- Access_Definition --
738 -----------------------
740 function Access_Definition
741 (Related_Nod : Node_Id;
742 N : Node_Id) return Entity_Id
744 Anon_Type : Entity_Id;
745 Anon_Scope : Entity_Id;
746 Desig_Type : Entity_Id;
747 Enclosing_Prot_Type : Entity_Id := Empty;
750 Check_SPARK_05_Restriction ("access type is not allowed", N);
752 if Is_Entry (Current_Scope)
753 and then Is_Task_Type (Etype (Scope (Current_Scope)))
755 Error_Msg_N ("task entries cannot have access parameters", N);
759 -- Ada 2005: For an object declaration the corresponding anonymous
760 -- type is declared in the current scope.
762 -- If the access definition is the return type of another access to
763 -- function, scope is the current one, because it is the one of the
764 -- current type declaration, except for the pathological case below.
766 if Nkind_In (Related_Nod, N_Object_Declaration,
767 N_Access_Function_Definition)
769 Anon_Scope := Current_Scope;
771 -- A pathological case: function returning access functions that
772 -- return access functions, etc. Each anonymous access type created
773 -- is in the enclosing scope of the outermost function.
780 while Nkind_In (Par, N_Access_Function_Definition,
786 if Nkind (Par) = N_Function_Specification then
787 Anon_Scope := Scope (Defining_Entity (Par));
791 -- For the anonymous function result case, retrieve the scope of the
792 -- function specification's associated entity rather than using the
793 -- current scope. The current scope will be the function itself if the
794 -- formal part is currently being analyzed, but will be the parent scope
795 -- in the case of a parameterless function, and we always want to use
796 -- the function's parent scope. Finally, if the function is a child
797 -- unit, we must traverse the tree to retrieve the proper entity.
799 elsif Nkind (Related_Nod) = N_Function_Specification
800 and then Nkind (Parent (N)) /= N_Parameter_Specification
802 -- If the current scope is a protected type, the anonymous access
803 -- is associated with one of the protected operations, and must
804 -- be available in the scope that encloses the protected declaration.
805 -- Otherwise the type is in the scope enclosing the subprogram.
807 -- If the function has formals, The return type of a subprogram
808 -- declaration is analyzed in the scope of the subprogram (see
809 -- Process_Formals) and thus the protected type, if present, is
810 -- the scope of the current function scope.
812 if Ekind (Current_Scope) = E_Protected_Type then
813 Enclosing_Prot_Type := Current_Scope;
815 elsif Ekind (Current_Scope) = E_Function
816 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
818 Enclosing_Prot_Type := Scope (Current_Scope);
821 if Present (Enclosing_Prot_Type) then
822 Anon_Scope := Scope (Enclosing_Prot_Type);
825 Anon_Scope := Scope (Defining_Entity (Related_Nod));
828 -- For an access type definition, if the current scope is a child
829 -- unit it is the scope of the type.
831 elsif Is_Compilation_Unit (Current_Scope) then
832 Anon_Scope := Current_Scope;
834 -- For access formals, access components, and access discriminants, the
835 -- scope is that of the enclosing declaration,
838 Anon_Scope := Scope (Current_Scope);
843 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
846 and then Ada_Version >= Ada_2005
848 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
851 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
852 -- the corresponding semantic routine
854 if Present (Access_To_Subprogram_Definition (N)) then
856 -- Compiler runtime units are compiled in Ada 2005 mode when building
857 -- the runtime library but must also be compilable in Ada 95 mode
858 -- (when bootstrapping the compiler).
860 Check_Compiler_Unit ("anonymous access to subprogram", N);
862 Access_Subprogram_Declaration
863 (T_Name => Anon_Type,
864 T_Def => Access_To_Subprogram_Definition (N));
866 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
868 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
870 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
873 Set_Can_Use_Internal_Rep
874 (Anon_Type, not Always_Compatible_Rep_On_Target);
876 -- If the anonymous access is associated with a protected operation,
877 -- create a reference to it after the enclosing protected definition
878 -- because the itype will be used in the subsequent bodies.
880 if Ekind (Current_Scope) = E_Protected_Type then
881 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
887 Find_Type (Subtype_Mark (N));
888 Desig_Type := Entity (Subtype_Mark (N));
890 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
891 Set_Etype (Anon_Type, Anon_Type);
893 -- Make sure the anonymous access type has size and alignment fields
894 -- set, as required by gigi. This is necessary in the case of the
895 -- Task_Body_Procedure.
897 if not Has_Private_Component (Desig_Type) then
898 Layout_Type (Anon_Type);
901 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
902 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
903 -- the null value is allowed. In Ada 95 the null value is never allowed.
905 if Ada_Version >= Ada_2005 then
906 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
908 Set_Can_Never_Be_Null (Anon_Type, True);
911 -- The anonymous access type is as public as the discriminated type or
912 -- subprogram that defines it. It is imported (for back-end purposes)
913 -- if the designated type is.
915 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
917 -- Ada 2005 (AI-231): Propagate the access-constant attribute
919 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
921 -- The context is either a subprogram declaration, object declaration,
922 -- or an access discriminant, in a private or a full type declaration.
923 -- In the case of a subprogram, if the designated type is incomplete,
924 -- the operation will be a primitive operation of the full type, to be
925 -- updated subsequently. If the type is imported through a limited_with
926 -- clause, the subprogram is not a primitive operation of the type
927 -- (which is declared elsewhere in some other scope).
929 if Ekind (Desig_Type) = E_Incomplete_Type
930 and then not From_Limited_With (Desig_Type)
931 and then Is_Overloadable (Current_Scope)
933 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
934 Set_Has_Delayed_Freeze (Current_Scope);
937 -- Ada 2005: If the designated type is an interface that may contain
938 -- tasks, create a Master entity for the declaration. This must be done
939 -- before expansion of the full declaration, because the declaration may
940 -- include an expression that is an allocator, whose expansion needs the
941 -- proper Master for the created tasks.
943 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
945 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
947 Build_Class_Wide_Master (Anon_Type);
949 -- Similarly, if the type is an anonymous access that designates
950 -- tasks, create a master entity for it in the current context.
952 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
954 Build_Master_Entity (Defining_Identifier (Related_Nod));
955 Build_Master_Renaming (Anon_Type);
959 -- For a private component of a protected type, it is imperative that
960 -- the back-end elaborate the type immediately after the protected
961 -- declaration, because this type will be used in the declarations
962 -- created for the component within each protected body, so we must
963 -- create an itype reference for it now.
965 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
966 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
968 -- Similarly, if the access definition is the return result of a
969 -- function, create an itype reference for it because it will be used
970 -- within the function body. For a regular function that is not a
971 -- compilation unit, insert reference after the declaration. For a
972 -- protected operation, insert it after the enclosing protected type
973 -- declaration. In either case, do not create a reference for a type
974 -- obtained through a limited_with clause, because this would introduce
975 -- semantic dependencies.
977 -- Similarly, do not create a reference if the designated type is a
978 -- generic formal, because no use of it will reach the backend.
980 elsif Nkind (Related_Nod) = N_Function_Specification
981 and then not From_Limited_With (Desig_Type)
982 and then not Is_Generic_Type (Desig_Type)
984 if Present (Enclosing_Prot_Type) then
985 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
987 elsif Is_List_Member (Parent (Related_Nod))
988 and then Nkind (Parent (N)) /= N_Parameter_Specification
990 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
993 -- Finally, create an itype reference for an object declaration of an
994 -- anonymous access type. This is strictly necessary only for deferred
995 -- constants, but in any case will avoid out-of-scope problems in the
998 elsif Nkind (Related_Nod) = N_Object_Declaration then
999 Build_Itype_Reference (Anon_Type, Related_Nod);
1003 end Access_Definition;
1005 -----------------------------------
1006 -- Access_Subprogram_Declaration --
1007 -----------------------------------
1009 procedure Access_Subprogram_Declaration
1010 (T_Name : Entity_Id;
1013 procedure Check_For_Premature_Usage (Def : Node_Id);
1014 -- Check that type T_Name is not used, directly or recursively, as a
1015 -- parameter or a return type in Def. Def is either a subtype, an
1016 -- access_definition, or an access_to_subprogram_definition.
1018 -------------------------------
1019 -- Check_For_Premature_Usage --
1020 -------------------------------
1022 procedure Check_For_Premature_Usage (Def : Node_Id) is
1026 -- Check for a subtype mark
1028 if Nkind (Def) in N_Has_Etype then
1029 if Etype (Def) = T_Name then
1031 ("type& cannot be used before end of its declaration", Def);
1034 -- If this is not a subtype, then this is an access_definition
1036 elsif Nkind (Def) = N_Access_Definition then
1037 if Present (Access_To_Subprogram_Definition (Def)) then
1038 Check_For_Premature_Usage
1039 (Access_To_Subprogram_Definition (Def));
1041 Check_For_Premature_Usage (Subtype_Mark (Def));
1044 -- The only cases left are N_Access_Function_Definition and
1045 -- N_Access_Procedure_Definition.
1048 if Present (Parameter_Specifications (Def)) then
1049 Param := First (Parameter_Specifications (Def));
1050 while Present (Param) loop
1051 Check_For_Premature_Usage (Parameter_Type (Param));
1052 Param := Next (Param);
1056 if Nkind (Def) = N_Access_Function_Definition then
1057 Check_For_Premature_Usage (Result_Definition (Def));
1060 end Check_For_Premature_Usage;
1064 Formals : constant List_Id := Parameter_Specifications (T_Def);
1067 Desig_Type : constant Entity_Id :=
1068 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1070 -- Start of processing for Access_Subprogram_Declaration
1073 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1075 -- Associate the Itype node with the inner full-type declaration or
1076 -- subprogram spec or entry body. This is required to handle nested
1077 -- anonymous declarations. For example:
1080 -- (X : access procedure
1081 -- (Y : access procedure
1084 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1085 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1086 N_Private_Type_Declaration,
1087 N_Private_Extension_Declaration,
1088 N_Procedure_Specification,
1089 N_Function_Specification,
1093 Nkind_In (D_Ityp, N_Object_Declaration,
1094 N_Object_Renaming_Declaration,
1095 N_Formal_Object_Declaration,
1096 N_Formal_Type_Declaration,
1097 N_Task_Type_Declaration,
1098 N_Protected_Type_Declaration))
1100 D_Ityp := Parent (D_Ityp);
1101 pragma Assert (D_Ityp /= Empty);
1104 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1106 if Nkind_In (D_Ityp, N_Procedure_Specification,
1107 N_Function_Specification)
1109 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1111 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1112 N_Object_Declaration,
1113 N_Object_Renaming_Declaration,
1114 N_Formal_Type_Declaration)
1116 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1119 if Nkind (T_Def) = N_Access_Function_Definition then
1120 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1122 Acc : constant Node_Id := Result_Definition (T_Def);
1125 if Present (Access_To_Subprogram_Definition (Acc))
1127 Protected_Present (Access_To_Subprogram_Definition (Acc))
1131 Replace_Anonymous_Access_To_Protected_Subprogram
1137 Access_Definition (T_Def, Result_Definition (T_Def)));
1142 Analyze (Result_Definition (T_Def));
1145 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1148 -- If a null exclusion is imposed on the result type, then
1149 -- create a null-excluding itype (an access subtype) and use
1150 -- it as the function's Etype.
1152 if Is_Access_Type (Typ)
1153 and then Null_Exclusion_In_Return_Present (T_Def)
1155 Set_Etype (Desig_Type,
1156 Create_Null_Excluding_Itype
1158 Related_Nod => T_Def,
1159 Scope_Id => Current_Scope));
1162 if From_Limited_With (Typ) then
1164 -- AI05-151: Incomplete types are allowed in all basic
1165 -- declarations, including access to subprograms.
1167 if Ada_Version >= Ada_2012 then
1172 ("illegal use of incomplete type&",
1173 Result_Definition (T_Def), Typ);
1176 elsif Ekind (Current_Scope) = E_Package
1177 and then In_Private_Part (Current_Scope)
1179 if Ekind (Typ) = E_Incomplete_Type then
1180 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1182 elsif Is_Class_Wide_Type (Typ)
1183 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1186 (Desig_Type, Private_Dependents (Etype (Typ)));
1190 Set_Etype (Desig_Type, Typ);
1195 if not (Is_Type (Etype (Desig_Type))) then
1197 ("expect type in function specification",
1198 Result_Definition (T_Def));
1202 Set_Etype (Desig_Type, Standard_Void_Type);
1205 if Present (Formals) then
1206 Push_Scope (Desig_Type);
1208 -- Some special tests here. These special tests can be removed
1209 -- if and when Itypes always have proper parent pointers to their
1212 -- Special test 1) Link defining_identifier of formals. Required by
1213 -- First_Formal to provide its functionality.
1219 F := First (Formals);
1221 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1222 -- when it is part of an unconstrained type and subtype expansion
1223 -- is disabled. To avoid back-end problems with shared profiles,
1224 -- use previous subprogram type as the designated type, and then
1225 -- remove scope added above.
1227 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1229 Set_Etype (T_Name, T_Name);
1230 Init_Size_Align (T_Name);
1231 Set_Directly_Designated_Type (T_Name,
1232 Scope (Defining_Identifier (F)));
1237 while Present (F) loop
1238 if No (Parent (Defining_Identifier (F))) then
1239 Set_Parent (Defining_Identifier (F), F);
1246 Process_Formals (Formals, Parent (T_Def));
1248 -- Special test 2) End_Scope requires that the parent pointer be set
1249 -- to something reasonable, but Itypes don't have parent pointers. So
1250 -- we set it and then unset it ???
1252 Set_Parent (Desig_Type, T_Name);
1254 Set_Parent (Desig_Type, Empty);
1257 -- Check for premature usage of the type being defined
1259 Check_For_Premature_Usage (T_Def);
1261 -- The return type and/or any parameter type may be incomplete. Mark the
1262 -- subprogram_type as depending on the incomplete type, so that it can
1263 -- be updated when the full type declaration is seen. This only applies
1264 -- to incomplete types declared in some enclosing scope, not to limited
1265 -- views from other packages.
1267 -- Prior to Ada 2012, access to functions can only have in_parameters.
1269 if Present (Formals) then
1270 Formal := First_Formal (Desig_Type);
1271 while Present (Formal) loop
1272 if Ekind (Formal) /= E_In_Parameter
1273 and then Nkind (T_Def) = N_Access_Function_Definition
1274 and then Ada_Version < Ada_2012
1276 Error_Msg_N ("functions can only have IN parameters", Formal);
1279 if Ekind (Etype (Formal)) = E_Incomplete_Type
1280 and then In_Open_Scopes (Scope (Etype (Formal)))
1282 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1283 Set_Has_Delayed_Freeze (Desig_Type);
1286 Next_Formal (Formal);
1290 -- Check whether an indirect call without actuals may be possible. This
1291 -- is used when resolving calls whose result is then indexed.
1293 May_Need_Actuals (Desig_Type);
1295 -- If the return type is incomplete, this is legal as long as the type
1296 -- is declared in the current scope and will be completed in it (rather
1297 -- than being part of limited view).
1299 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1300 and then not Has_Delayed_Freeze (Desig_Type)
1301 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1303 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1304 Set_Has_Delayed_Freeze (Desig_Type);
1307 Check_Delayed_Subprogram (Desig_Type);
1309 if Protected_Present (T_Def) then
1310 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1311 Set_Convention (Desig_Type, Convention_Protected);
1313 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1316 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1318 Set_Etype (T_Name, T_Name);
1319 Init_Size_Align (T_Name);
1320 Set_Directly_Designated_Type (T_Name, Desig_Type);
1322 Generate_Reference_To_Formals (T_Name);
1324 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1326 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1328 Check_Restriction (No_Access_Subprograms, T_Def);
1329 end Access_Subprogram_Declaration;
1331 ----------------------------
1332 -- Access_Type_Declaration --
1333 ----------------------------
1335 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1336 P : constant Node_Id := Parent (Def);
1337 S : constant Node_Id := Subtype_Indication (Def);
1339 Full_Desig : Entity_Id;
1342 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1344 -- Check for permissible use of incomplete type
1346 if Nkind (S) /= N_Subtype_Indication then
1349 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1350 Set_Directly_Designated_Type (T, Entity (S));
1352 -- If the designated type is a limited view, we cannot tell if
1353 -- the full view contains tasks, and there is no way to handle
1354 -- that full view in a client. We create a master entity for the
1355 -- scope, which will be used when a client determines that one
1358 if From_Limited_With (Entity (S))
1359 and then not Is_Class_Wide_Type (Entity (S))
1361 Set_Ekind (T, E_Access_Type);
1362 Build_Master_Entity (T);
1363 Build_Master_Renaming (T);
1367 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1370 -- If the access definition is of the form: ACCESS NOT NULL ..
1371 -- the subtype indication must be of an access type. Create
1372 -- a null-excluding subtype of it.
1374 if Null_Excluding_Subtype (Def) then
1375 if not Is_Access_Type (Entity (S)) then
1376 Error_Msg_N ("null exclusion must apply to access type", Def);
1380 Loc : constant Source_Ptr := Sloc (S);
1382 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1386 Make_Subtype_Declaration (Loc,
1387 Defining_Identifier => Nam,
1388 Subtype_Indication =>
1389 New_Occurrence_Of (Entity (S), Loc));
1390 Set_Null_Exclusion_Present (Decl);
1391 Insert_Before (Parent (Def), Decl);
1393 Set_Entity (S, Nam);
1399 Set_Directly_Designated_Type (T,
1400 Process_Subtype (S, P, T, 'P'));
1403 if All_Present (Def) or Constant_Present (Def) then
1404 Set_Ekind (T, E_General_Access_Type);
1406 Set_Ekind (T, E_Access_Type);
1409 Full_Desig := Designated_Type (T);
1411 if Base_Type (Full_Desig) = T then
1412 Error_Msg_N ("access type cannot designate itself", S);
1414 -- In Ada 2005, the type may have a limited view through some unit in
1415 -- its own context, allowing the following circularity that cannot be
1416 -- detected earlier.
1418 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1421 ("access type cannot designate its own classwide type", S);
1423 -- Clean up indication of tagged status to prevent cascaded errors
1425 Set_Is_Tagged_Type (T, False);
1430 -- If the type has appeared already in a with_type clause, it is frozen
1431 -- and the pointer size is already set. Else, initialize.
1433 if not From_Limited_With (T) then
1434 Init_Size_Align (T);
1437 -- Note that Has_Task is always false, since the access type itself
1438 -- is not a task type. See Einfo for more description on this point.
1439 -- Exactly the same consideration applies to Has_Controlled_Component
1440 -- and to Has_Protected.
1442 Set_Has_Task (T, False);
1443 Set_Has_Controlled_Component (T, False);
1444 Set_Has_Protected (T, False);
1446 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1447 -- problems where an incomplete view of this entity has been previously
1448 -- established by a limited with and an overlaid version of this field
1449 -- (Stored_Constraint) was initialized for the incomplete view.
1451 -- This reset is performed in most cases except where the access type
1452 -- has been created for the purposes of allocating or deallocating a
1453 -- build-in-place object. Such access types have explicitly set pools
1454 -- and finalization masters.
1456 if No (Associated_Storage_Pool (T)) then
1457 Set_Finalization_Master (T, Empty);
1460 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1463 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1464 Set_Is_Access_Constant (T, Constant_Present (Def));
1465 end Access_Type_Declaration;
1467 ----------------------------------
1468 -- Add_Interface_Tag_Components --
1469 ----------------------------------
1471 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1472 Loc : constant Source_Ptr := Sloc (N);
1476 procedure Add_Tag (Iface : Entity_Id);
1477 -- Add tag for one of the progenitor interfaces
1483 procedure Add_Tag (Iface : Entity_Id) is
1490 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1492 -- This is a reasonable place to propagate predicates
1494 if Has_Predicates (Iface) then
1495 Set_Has_Predicates (Typ);
1499 Make_Component_Definition (Loc,
1500 Aliased_Present => True,
1501 Subtype_Indication =>
1502 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1504 Tag := Make_Temporary (Loc, 'V');
1507 Make_Component_Declaration (Loc,
1508 Defining_Identifier => Tag,
1509 Component_Definition => Def);
1511 Analyze_Component_Declaration (Decl);
1513 Set_Analyzed (Decl);
1514 Set_Ekind (Tag, E_Component);
1516 Set_Is_Aliased (Tag);
1517 Set_Related_Type (Tag, Iface);
1518 Init_Component_Location (Tag);
1520 pragma Assert (Is_Frozen (Iface));
1522 Set_DT_Entry_Count (Tag,
1523 DT_Entry_Count (First_Entity (Iface)));
1525 if No (Last_Tag) then
1528 Insert_After (Last_Tag, Decl);
1533 -- If the ancestor has discriminants we need to give special support
1534 -- to store the offset_to_top value of the secondary dispatch tables.
1535 -- For this purpose we add a supplementary component just after the
1536 -- field that contains the tag associated with each secondary DT.
1538 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1540 Make_Component_Definition (Loc,
1541 Subtype_Indication =>
1542 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1544 Offset := Make_Temporary (Loc, 'V');
1547 Make_Component_Declaration (Loc,
1548 Defining_Identifier => Offset,
1549 Component_Definition => Def);
1551 Analyze_Component_Declaration (Decl);
1553 Set_Analyzed (Decl);
1554 Set_Ekind (Offset, E_Component);
1555 Set_Is_Aliased (Offset);
1556 Set_Related_Type (Offset, Iface);
1557 Init_Component_Location (Offset);
1558 Insert_After (Last_Tag, Decl);
1569 -- Start of processing for Add_Interface_Tag_Components
1572 if not RTE_Available (RE_Interface_Tag) then
1574 ("(Ada 2005) interface types not supported by this run-time!",
1579 if Ekind (Typ) /= E_Record_Type
1580 or else (Is_Concurrent_Record_Type (Typ)
1581 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1582 or else (not Is_Concurrent_Record_Type (Typ)
1583 and then No (Interfaces (Typ))
1584 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1589 -- Find the current last tag
1591 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1592 Ext := Record_Extension_Part (Type_Definition (N));
1594 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1595 Ext := Type_Definition (N);
1600 if not (Present (Component_List (Ext))) then
1601 Set_Null_Present (Ext, False);
1603 Set_Component_List (Ext,
1604 Make_Component_List (Loc,
1605 Component_Items => L,
1606 Null_Present => False));
1608 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1609 L := Component_Items
1611 (Record_Extension_Part
1612 (Type_Definition (N))));
1614 L := Component_Items
1616 (Type_Definition (N)));
1619 -- Find the last tag component
1622 while Present (Comp) loop
1623 if Nkind (Comp) = N_Component_Declaration
1624 and then Is_Tag (Defining_Identifier (Comp))
1633 -- At this point L references the list of components and Last_Tag
1634 -- references the current last tag (if any). Now we add the tag
1635 -- corresponding with all the interfaces that are not implemented
1638 if Present (Interfaces (Typ)) then
1639 Elmt := First_Elmt (Interfaces (Typ));
1640 while Present (Elmt) loop
1641 Add_Tag (Node (Elmt));
1645 end Add_Interface_Tag_Components;
1647 -------------------------------------
1648 -- Add_Internal_Interface_Entities --
1649 -------------------------------------
1651 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1654 Iface_Elmt : Elmt_Id;
1655 Iface_Prim : Entity_Id;
1656 Ifaces_List : Elist_Id;
1657 New_Subp : Entity_Id := Empty;
1659 Restore_Scope : Boolean := False;
1662 pragma Assert (Ada_Version >= Ada_2005
1663 and then Is_Record_Type (Tagged_Type)
1664 and then Is_Tagged_Type (Tagged_Type)
1665 and then Has_Interfaces (Tagged_Type)
1666 and then not Is_Interface (Tagged_Type));
1668 -- Ensure that the internal entities are added to the scope of the type
1670 if Scope (Tagged_Type) /= Current_Scope then
1671 Push_Scope (Scope (Tagged_Type));
1672 Restore_Scope := True;
1675 Collect_Interfaces (Tagged_Type, Ifaces_List);
1677 Iface_Elmt := First_Elmt (Ifaces_List);
1678 while Present (Iface_Elmt) loop
1679 Iface := Node (Iface_Elmt);
1681 -- Originally we excluded here from this processing interfaces that
1682 -- are parents of Tagged_Type because their primitives are located
1683 -- in the primary dispatch table (and hence no auxiliary internal
1684 -- entities are required to handle secondary dispatch tables in such
1685 -- case). However, these auxiliary entities are also required to
1686 -- handle derivations of interfaces in formals of generics (see
1687 -- Derive_Subprograms).
1689 Elmt := First_Elmt (Primitive_Operations (Iface));
1690 while Present (Elmt) loop
1691 Iface_Prim := Node (Elmt);
1693 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1695 Find_Primitive_Covering_Interface
1696 (Tagged_Type => Tagged_Type,
1697 Iface_Prim => Iface_Prim);
1699 if No (Prim) and then Serious_Errors_Detected > 0 then
1703 pragma Assert (Present (Prim));
1705 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1706 -- differs from the name of the interface primitive then it is
1707 -- a private primitive inherited from a parent type. In such
1708 -- case, given that Tagged_Type covers the interface, the
1709 -- inherited private primitive becomes visible. For such
1710 -- purpose we add a new entity that renames the inherited
1711 -- private primitive.
1713 if Chars (Prim) /= Chars (Iface_Prim) then
1714 pragma Assert (Has_Suffix (Prim, 'P'));
1716 (New_Subp => New_Subp,
1717 Parent_Subp => Iface_Prim,
1718 Derived_Type => Tagged_Type,
1719 Parent_Type => Iface);
1720 Set_Alias (New_Subp, Prim);
1721 Set_Is_Abstract_Subprogram
1722 (New_Subp, Is_Abstract_Subprogram (Prim));
1726 (New_Subp => New_Subp,
1727 Parent_Subp => Iface_Prim,
1728 Derived_Type => Tagged_Type,
1729 Parent_Type => Iface);
1731 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1732 -- associated with interface types. These entities are
1733 -- only registered in the list of primitives of its
1734 -- corresponding tagged type because they are only used
1735 -- to fill the contents of the secondary dispatch tables.
1736 -- Therefore they are removed from the homonym chains.
1738 Set_Is_Hidden (New_Subp);
1739 Set_Is_Internal (New_Subp);
1740 Set_Alias (New_Subp, Prim);
1741 Set_Is_Abstract_Subprogram
1742 (New_Subp, Is_Abstract_Subprogram (Prim));
1743 Set_Interface_Alias (New_Subp, Iface_Prim);
1745 -- If the returned type is an interface then propagate it to
1746 -- the returned type. Needed by the thunk to generate the code
1747 -- which displaces "this" to reference the corresponding
1748 -- secondary dispatch table in the returned object.
1750 if Is_Interface (Etype (Iface_Prim)) then
1751 Set_Etype (New_Subp, Etype (Iface_Prim));
1754 -- Internal entities associated with interface types are
1755 -- only registered in the list of primitives of the tagged
1756 -- type. They are only used to fill the contents of the
1757 -- secondary dispatch tables. Therefore they are not needed
1758 -- in the homonym chains.
1760 Remove_Homonym (New_Subp);
1762 -- Hidden entities associated with interfaces must have set
1763 -- the Has_Delay_Freeze attribute to ensure that, in case of
1764 -- locally defined tagged types (or compiling with static
1765 -- dispatch tables generation disabled) the corresponding
1766 -- entry of the secondary dispatch table is filled when
1767 -- such an entity is frozen.
1769 Set_Has_Delayed_Freeze (New_Subp);
1776 Next_Elmt (Iface_Elmt);
1779 if Restore_Scope then
1782 end Add_Internal_Interface_Entities;
1784 -----------------------------------
1785 -- Analyze_Component_Declaration --
1786 -----------------------------------
1788 procedure Analyze_Component_Declaration (N : Node_Id) is
1789 Id : constant Entity_Id := Defining_Identifier (N);
1790 E : constant Node_Id := Expression (N);
1791 Typ : constant Node_Id :=
1792 Subtype_Indication (Component_Definition (N));
1796 function Contains_POC (Constr : Node_Id) return Boolean;
1797 -- Determines whether a constraint uses the discriminant of a record
1798 -- type thus becoming a per-object constraint (POC).
1800 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1801 -- Typ is the type of the current component, check whether this type is
1802 -- a limited type. Used to validate declaration against that of
1803 -- enclosing record.
1809 function Contains_POC (Constr : Node_Id) return Boolean is
1811 -- Prevent cascaded errors
1813 if Error_Posted (Constr) then
1817 case Nkind (Constr) is
1818 when N_Attribute_Reference =>
1819 return Attribute_Name (Constr) = Name_Access
1820 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1822 when N_Discriminant_Association =>
1823 return Denotes_Discriminant (Expression (Constr));
1825 when N_Identifier =>
1826 return Denotes_Discriminant (Constr);
1828 when N_Index_Or_Discriminant_Constraint =>
1833 IDC := First (Constraints (Constr));
1834 while Present (IDC) loop
1836 -- One per-object constraint is sufficient
1838 if Contains_POC (IDC) then
1849 return Denotes_Discriminant (Low_Bound (Constr))
1851 Denotes_Discriminant (High_Bound (Constr));
1853 when N_Range_Constraint =>
1854 return Denotes_Discriminant (Range_Expression (Constr));
1862 ----------------------
1863 -- Is_Known_Limited --
1864 ----------------------
1866 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1867 P : constant Entity_Id := Etype (Typ);
1868 R : constant Entity_Id := Root_Type (Typ);
1871 if Is_Limited_Record (Typ) then
1874 -- If the root type is limited (and not a limited interface)
1875 -- so is the current type
1877 elsif Is_Limited_Record (R)
1878 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1882 -- Else the type may have a limited interface progenitor, but a
1883 -- limited record parent.
1885 elsif R /= P and then Is_Limited_Record (P) then
1891 end Is_Known_Limited;
1893 -- Start of processing for Analyze_Component_Declaration
1896 Generate_Definition (Id);
1899 if Present (Typ) then
1900 T := Find_Type_Of_Object
1901 (Subtype_Indication (Component_Definition (N)), N);
1903 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1904 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1907 -- Ada 2005 (AI-230): Access Definition case
1910 pragma Assert (Present
1911 (Access_Definition (Component_Definition (N))));
1913 T := Access_Definition
1915 N => Access_Definition (Component_Definition (N)));
1916 Set_Is_Local_Anonymous_Access (T);
1918 -- Ada 2005 (AI-254)
1920 if Present (Access_To_Subprogram_Definition
1921 (Access_Definition (Component_Definition (N))))
1922 and then Protected_Present (Access_To_Subprogram_Definition
1924 (Component_Definition (N))))
1926 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1930 -- If the subtype is a constrained subtype of the enclosing record,
1931 -- (which must have a partial view) the back-end does not properly
1932 -- handle the recursion. Rewrite the component declaration with an
1933 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1934 -- the tree directly because side effects have already been removed from
1935 -- discriminant constraints.
1937 if Ekind (T) = E_Access_Subtype
1938 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1939 and then Comes_From_Source (T)
1940 and then Nkind (Parent (T)) = N_Subtype_Declaration
1941 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1944 (Subtype_Indication (Component_Definition (N)),
1945 New_Copy_Tree (Subtype_Indication (Parent (T))));
1946 T := Find_Type_Of_Object
1947 (Subtype_Indication (Component_Definition (N)), N);
1950 -- If the component declaration includes a default expression, then we
1951 -- check that the component is not of a limited type (RM 3.7(5)),
1952 -- and do the special preanalysis of the expression (see section on
1953 -- "Handling of Default and Per-Object Expressions" in the spec of
1957 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1958 Preanalyze_Default_Expression (E, T);
1959 Check_Initialization (T, E);
1961 if Ada_Version >= Ada_2005
1962 and then Ekind (T) = E_Anonymous_Access_Type
1963 and then Etype (E) /= Any_Type
1965 -- Check RM 3.9.2(9): "if the expected type for an expression is
1966 -- an anonymous access-to-specific tagged type, then the object
1967 -- designated by the expression shall not be dynamically tagged
1968 -- unless it is a controlling operand in a call on a dispatching
1971 if Is_Tagged_Type (Directly_Designated_Type (T))
1973 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1975 Ekind (Directly_Designated_Type (Etype (E))) =
1979 ("access to specific tagged type required (RM 3.9.2(9))", E);
1982 -- (Ada 2005: AI-230): Accessibility check for anonymous
1985 if Type_Access_Level (Etype (E)) >
1986 Deepest_Type_Access_Level (T)
1989 ("expression has deeper access level than component " &
1990 "(RM 3.10.2 (12.2))", E);
1993 -- The initialization expression is a reference to an access
1994 -- discriminant. The type of the discriminant is always deeper
1995 -- than any access type.
1997 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1998 and then Is_Entity_Name (E)
1999 and then Ekind (Entity (E)) = E_In_Parameter
2000 and then Present (Discriminal_Link (Entity (E)))
2003 ("discriminant has deeper accessibility level than target",
2009 -- The parent type may be a private view with unknown discriminants,
2010 -- and thus unconstrained. Regular components must be constrained.
2012 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
2013 if Is_Class_Wide_Type (T) then
2015 ("class-wide subtype with unknown discriminants" &
2016 " in component declaration",
2017 Subtype_Indication (Component_Definition (N)));
2020 ("unconstrained subtype in component declaration",
2021 Subtype_Indication (Component_Definition (N)));
2024 -- Components cannot be abstract, except for the special case of
2025 -- the _Parent field (case of extending an abstract tagged type)
2027 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2028 Error_Msg_N ("type of a component cannot be abstract", N);
2032 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2034 -- The component declaration may have a per-object constraint, set
2035 -- the appropriate flag in the defining identifier of the subtype.
2037 if Present (Subtype_Indication (Component_Definition (N))) then
2039 Sindic : constant Node_Id :=
2040 Subtype_Indication (Component_Definition (N));
2042 if Nkind (Sindic) = N_Subtype_Indication
2043 and then Present (Constraint (Sindic))
2044 and then Contains_POC (Constraint (Sindic))
2046 Set_Has_Per_Object_Constraint (Id);
2051 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2052 -- out some static checks.
2054 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2055 Null_Exclusion_Static_Checks (N);
2058 -- If this component is private (or depends on a private type), flag the
2059 -- record type to indicate that some operations are not available.
2061 P := Private_Component (T);
2065 -- Check for circular definitions
2067 if P = Any_Type then
2068 Set_Etype (Id, Any_Type);
2070 -- There is a gap in the visibility of operations only if the
2071 -- component type is not defined in the scope of the record type.
2073 elsif Scope (P) = Scope (Current_Scope) then
2076 elsif Is_Limited_Type (P) then
2077 Set_Is_Limited_Composite (Current_Scope);
2080 Set_Is_Private_Composite (Current_Scope);
2085 and then Is_Limited_Type (T)
2086 and then Chars (Id) /= Name_uParent
2087 and then Is_Tagged_Type (Current_Scope)
2089 if Is_Derived_Type (Current_Scope)
2090 and then not Is_Known_Limited (Current_Scope)
2093 ("extension of nonlimited type cannot have limited components",
2096 if Is_Interface (Root_Type (Current_Scope)) then
2098 ("\limitedness is not inherited from limited interface", N);
2099 Error_Msg_N ("\add LIMITED to type indication", N);
2102 Explain_Limited_Type (T, N);
2103 Set_Etype (Id, Any_Type);
2104 Set_Is_Limited_Composite (Current_Scope, False);
2106 elsif not Is_Derived_Type (Current_Scope)
2107 and then not Is_Limited_Record (Current_Scope)
2108 and then not Is_Concurrent_Type (Current_Scope)
2111 ("nonlimited tagged type cannot have limited components", N);
2112 Explain_Limited_Type (T, N);
2113 Set_Etype (Id, Any_Type);
2114 Set_Is_Limited_Composite (Current_Scope, False);
2118 Set_Original_Record_Component (Id, Id);
2120 if Has_Aspects (N) then
2121 Analyze_Aspect_Specifications (N, Id);
2124 Analyze_Dimension (N);
2125 end Analyze_Component_Declaration;
2127 --------------------------
2128 -- Analyze_Declarations --
2129 --------------------------
2131 procedure Analyze_Declarations (L : List_Id) is
2134 procedure Adjust_Decl;
2135 -- Adjust Decl not to include implicit label declarations, since these
2136 -- have strange Sloc values that result in elaboration check problems.
2137 -- (They have the sloc of the label as found in the source, and that
2138 -- is ahead of the current declarative part).
2140 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2141 -- Determine whether Body_Decl denotes the body of a late controlled
2142 -- primitive (either Initialize, Adjust or Finalize). If this is the
2143 -- case, add a proper spec if the body lacks one. The spec is inserted
2144 -- before Body_Decl and immedately analyzed.
2146 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2147 -- Spec_Id is the entity of a package that may define abstract states.
2148 -- If the states have visible refinement, remove the visibility of each
2149 -- constituent at the end of the package body declarations.
2155 procedure Adjust_Decl is
2157 while Present (Prev (Decl))
2158 and then Nkind (Decl) = N_Implicit_Label_Declaration
2164 --------------------------------------
2165 -- Handle_Late_Controlled_Primitive --
2166 --------------------------------------
2168 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2169 Body_Spec : constant Node_Id := Specification (Body_Decl);
2170 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2171 Loc : constant Source_Ptr := Sloc (Body_Id);
2172 Params : constant List_Id :=
2173 Parameter_Specifications (Body_Spec);
2175 Spec_Id : Entity_Id;
2179 -- Consider only procedure bodies whose name matches one of the three
2180 -- controlled primitives.
2182 if Nkind (Body_Spec) /= N_Procedure_Specification
2183 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2189 -- A controlled primitive must have exactly one formal which is not
2190 -- an anonymous access type.
2192 elsif List_Length (Params) /= 1 then
2196 Typ := Parameter_Type (First (Params));
2198 if Nkind (Typ) = N_Access_Definition then
2204 -- The type of the formal must be derived from [Limited_]Controlled
2206 if not Is_Controlled (Entity (Typ)) then
2210 -- Check whether a specification exists for this body. We do not
2211 -- analyze the spec of the body in full, because it will be analyzed
2212 -- again when the body is properly analyzed, and we cannot create
2213 -- duplicate entries in the formals chain. We look for an explicit
2214 -- specification because the body may be an overriding operation and
2215 -- an inherited spec may be present.
2217 Spec_Id := Current_Entity (Body_Id);
2219 while Present (Spec_Id) loop
2220 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2221 and then Scope (Spec_Id) = Current_Scope
2222 and then Present (First_Formal (Spec_Id))
2223 and then No (Next_Formal (First_Formal (Spec_Id)))
2224 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2225 and then Comes_From_Source (Spec_Id)
2230 Spec_Id := Homonym (Spec_Id);
2233 -- At this point the body is known to be a late controlled primitive.
2234 -- Generate a matching spec and insert it before the body. Note the
2235 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2236 -- tree in this case.
2238 Spec := Copy_Separate_Tree (Body_Spec);
2240 -- Ensure that the subprogram declaration does not inherit the null
2241 -- indicator from the body as we now have a proper spec/body pair.
2243 Set_Null_Present (Spec, False);
2245 Insert_Before_And_Analyze (Body_Decl,
2246 Make_Subprogram_Declaration (Loc, Specification => Spec));
2247 end Handle_Late_Controlled_Primitive;
2249 --------------------------------
2250 -- Remove_Visible_Refinements --
2251 --------------------------------
2253 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2254 State_Elmt : Elmt_Id;
2256 if Present (Abstract_States (Spec_Id)) then
2257 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2258 while Present (State_Elmt) loop
2259 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2260 Next_Elmt (State_Elmt);
2263 end Remove_Visible_Refinements;
2268 Freeze_From : Entity_Id := Empty;
2269 Next_Decl : Node_Id;
2270 Spec_Id : Entity_Id;
2272 Body_Seen : Boolean := False;
2273 -- Flag set when the first body [stub] is encountered
2275 In_Package_Body : Boolean := False;
2276 -- Flag set when the current declaration list belongs to a package body
2278 -- Start of processing for Analyze_Declarations
2281 if Restriction_Check_Required (SPARK_05) then
2282 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2286 while Present (Decl) loop
2288 -- Package spec cannot contain a package declaration in SPARK
2290 if Nkind (Decl) = N_Package_Declaration
2291 and then Nkind (Parent (L)) = N_Package_Specification
2293 Check_SPARK_05_Restriction
2294 ("package specification cannot contain a package declaration",
2298 -- Complete analysis of declaration
2301 Next_Decl := Next (Decl);
2303 if No (Freeze_From) then
2304 Freeze_From := First_Entity (Current_Scope);
2307 -- At the end of a declarative part, freeze remaining entities
2308 -- declared in it. The end of the visible declarations of package
2309 -- specification is not the end of a declarative part if private
2310 -- declarations are present. The end of a package declaration is a
2311 -- freezing point only if it a library package. A task definition or
2312 -- protected type definition is not a freeze point either. Finally,
2313 -- we do not freeze entities in generic scopes, because there is no
2314 -- code generated for them and freeze nodes will be generated for
2317 -- The end of a package instantiation is not a freeze point, but
2318 -- for now we make it one, because the generic body is inserted
2319 -- (currently) immediately after. Generic instantiations will not
2320 -- be a freeze point once delayed freezing of bodies is implemented.
2321 -- (This is needed in any case for early instantiations ???).
2323 if No (Next_Decl) then
2324 if Nkind_In (Parent (L), N_Component_List,
2326 N_Protected_Definition)
2330 elsif Nkind (Parent (L)) /= N_Package_Specification then
2331 if Nkind (Parent (L)) = N_Package_Body then
2332 Freeze_From := First_Entity (Current_Scope);
2335 -- There may have been several freezing points previously,
2336 -- for example object declarations or subprogram bodies, but
2337 -- at the end of a declarative part we check freezing from
2338 -- the beginning, even though entities may already be frozen,
2339 -- in order to perform visibility checks on delayed aspects.
2342 Freeze_All (First_Entity (Current_Scope), Decl);
2343 Freeze_From := Last_Entity (Current_Scope);
2345 elsif Scope (Current_Scope) /= Standard_Standard
2346 and then not Is_Child_Unit (Current_Scope)
2347 and then No (Generic_Parent (Parent (L)))
2351 elsif L /= Visible_Declarations (Parent (L))
2352 or else No (Private_Declarations (Parent (L)))
2353 or else Is_Empty_List (Private_Declarations (Parent (L)))
2356 Freeze_All (First_Entity (Current_Scope), Decl);
2357 Freeze_From := Last_Entity (Current_Scope);
2360 -- If next node is a body then freeze all types before the body.
2361 -- An exception occurs for some expander-generated bodies. If these
2362 -- are generated at places where in general language rules would not
2363 -- allow a freeze point, then we assume that the expander has
2364 -- explicitly checked that all required types are properly frozen,
2365 -- and we do not cause general freezing here. This special circuit
2366 -- is used when the encountered body is marked as having already
2369 -- In all other cases (bodies that come from source, and expander
2370 -- generated bodies that have not been analyzed yet), freeze all
2371 -- types now. Note that in the latter case, the expander must take
2372 -- care to attach the bodies at a proper place in the tree so as to
2373 -- not cause unwanted freezing at that point.
2375 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2377 -- When a controlled type is frozen, the expander generates stream
2378 -- and controlled type support routines. If the freeze is caused
2379 -- by the stand alone body of Initialize, Adjust and Finalize, the
2380 -- expander will end up using the wrong version of these routines
2381 -- as the body has not been processed yet. To remedy this, detect
2382 -- a late controlled primitive and create a proper spec for it.
2383 -- This ensures that the primitive will override its inherited
2384 -- counterpart before the freeze takes place.
2386 -- If the declaration we just processed is a body, do not attempt
2387 -- to examine Next_Decl as the late primitive idiom can only apply
2388 -- to the first encountered body.
2390 -- The spec of the late primitive is not generated in ASIS mode to
2391 -- ensure a consistent list of primitives that indicates the true
2392 -- semantic structure of the program (which is not relevant when
2393 -- generating executable code.
2395 -- ??? a cleaner approach may be possible and/or this solution
2396 -- could be extended to general-purpose late primitives, TBD.
2398 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2402 if Nkind (Next_Decl) = N_Subprogram_Body then
2403 Handle_Late_Controlled_Primitive (Next_Decl);
2408 Freeze_All (Freeze_From, Decl);
2409 Freeze_From := Last_Entity (Current_Scope);
2415 -- Analyze the contracts of packages and their bodies
2418 Context := Parent (L);
2420 if Nkind (Context) = N_Package_Specification then
2422 -- When a package has private declarations, its contract must be
2423 -- analyzed at the end of the said declarations. This way both the
2424 -- analysis and freeze actions are properly synchronized in case
2425 -- of private type use within the contract.
2427 if L = Private_Declarations (Context) then
2428 Analyze_Package_Contract (Defining_Entity (Context));
2430 -- Build the bodies of the default initial condition procedures
2431 -- for all types subject to pragma Default_Initial_Condition.
2432 -- From a purely Ada stand point, this is a freezing activity,
2433 -- however freezing is not available under GNATprove_Mode. To
2434 -- accomodate both scenarios, the bodies are build at the end
2435 -- of private declaration analysis.
2437 Build_Default_Init_Cond_Procedure_Bodies (L);
2439 -- Otherwise the contract is analyzed at the end of the visible
2442 elsif L = Visible_Declarations (Context)
2443 and then No (Private_Declarations (Context))
2445 Analyze_Package_Contract (Defining_Entity (Context));
2448 elsif Nkind (Context) = N_Package_Body then
2449 In_Package_Body := True;
2450 Spec_Id := Corresponding_Spec (Context);
2452 Analyze_Package_Body_Contract (Defining_Entity (Context));
2456 -- Analyze the contracts of subprogram declarations, subprogram bodies
2457 -- and variables now due to the delayed visibility requirements of their
2461 while Present (Decl) loop
2462 if Nkind (Decl) = N_Object_Declaration then
2463 Analyze_Object_Contract (Defining_Entity (Decl));
2465 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2466 N_Subprogram_Declaration)
2468 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2470 elsif Nkind (Decl) = N_Subprogram_Body then
2471 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2473 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2474 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2480 -- State refinements are visible upto the end the of the package body
2481 -- declarations. Hide the refinements from visibility to restore the
2482 -- original state conditions.
2484 if In_Package_Body then
2485 Remove_Visible_Refinements (Spec_Id);
2487 end Analyze_Declarations;
2489 -----------------------------------
2490 -- Analyze_Full_Type_Declaration --
2491 -----------------------------------
2493 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2494 Def : constant Node_Id := Type_Definition (N);
2495 Def_Id : constant Entity_Id := Defining_Identifier (N);
2499 Is_Remote : constant Boolean :=
2500 (Is_Remote_Types (Current_Scope)
2501 or else Is_Remote_Call_Interface (Current_Scope))
2502 and then not (In_Private_Part (Current_Scope)
2503 or else In_Package_Body (Current_Scope));
2505 procedure Check_Ops_From_Incomplete_Type;
2506 -- If there is a tagged incomplete partial view of the type, traverse
2507 -- the primitives of the incomplete view and change the type of any
2508 -- controlling formals and result to indicate the full view. The
2509 -- primitives will be added to the full type's primitive operations
2510 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2511 -- is called from Process_Incomplete_Dependents).
2513 ------------------------------------
2514 -- Check_Ops_From_Incomplete_Type --
2515 ------------------------------------
2517 procedure Check_Ops_From_Incomplete_Type is
2524 and then Ekind (Prev) = E_Incomplete_Type
2525 and then Is_Tagged_Type (Prev)
2526 and then Is_Tagged_Type (T)
2528 Elmt := First_Elmt (Primitive_Operations (Prev));
2529 while Present (Elmt) loop
2532 Formal := First_Formal (Op);
2533 while Present (Formal) loop
2534 if Etype (Formal) = Prev then
2535 Set_Etype (Formal, T);
2538 Next_Formal (Formal);
2541 if Etype (Op) = Prev then
2548 end Check_Ops_From_Incomplete_Type;
2550 -- Start of processing for Analyze_Full_Type_Declaration
2553 Prev := Find_Type_Name (N);
2555 -- The full view, if present, now points to the current type
2556 -- If there is an incomplete partial view, set a link to it, to
2557 -- simplify the retrieval of primitive operations of the type.
2559 -- Ada 2005 (AI-50217): If the type was previously decorated when
2560 -- imported through a LIMITED WITH clause, it appears as incomplete
2561 -- but has no full view.
2563 if Ekind (Prev) = E_Incomplete_Type
2564 and then Present (Full_View (Prev))
2566 T := Full_View (Prev);
2567 Set_Incomplete_View (N, Parent (Prev));
2572 Set_Is_Pure (T, Is_Pure (Current_Scope));
2574 -- We set the flag Is_First_Subtype here. It is needed to set the
2575 -- corresponding flag for the Implicit class-wide-type created
2576 -- during tagged types processing.
2578 Set_Is_First_Subtype (T, True);
2580 -- Only composite types other than array types are allowed to have
2585 -- For derived types, the rule will be checked once we've figured
2586 -- out the parent type.
2588 when N_Derived_Type_Definition =>
2591 -- For record types, discriminants are allowed, unless we are in
2594 when N_Record_Definition =>
2595 if Present (Discriminant_Specifications (N)) then
2596 Check_SPARK_05_Restriction
2597 ("discriminant type is not allowed",
2599 (First (Discriminant_Specifications (N))));
2603 if Present (Discriminant_Specifications (N)) then
2605 ("elementary or array type cannot have discriminants",
2607 (First (Discriminant_Specifications (N))));
2611 -- Elaborate the type definition according to kind, and generate
2612 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2613 -- already done (this happens during the reanalysis that follows a call
2614 -- to the high level optimizer).
2616 if not Analyzed (T) then
2620 when N_Access_To_Subprogram_Definition =>
2621 Access_Subprogram_Declaration (T, Def);
2623 -- If this is a remote access to subprogram, we must create the
2624 -- equivalent fat pointer type, and related subprograms.
2627 Process_Remote_AST_Declaration (N);
2630 -- Validate categorization rule against access type declaration
2631 -- usually a violation in Pure unit, Shared_Passive unit.
2633 Validate_Access_Type_Declaration (T, N);
2635 when N_Access_To_Object_Definition =>
2636 Access_Type_Declaration (T, Def);
2638 -- Validate categorization rule against access type declaration
2639 -- usually a violation in Pure unit, Shared_Passive unit.
2641 Validate_Access_Type_Declaration (T, N);
2643 -- If we are in a Remote_Call_Interface package and define a
2644 -- RACW, then calling stubs and specific stream attributes
2648 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2650 Add_RACW_Features (Def_Id);
2653 -- Set no strict aliasing flag if config pragma seen
2655 if Opt.No_Strict_Aliasing then
2656 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2659 when N_Array_Type_Definition =>
2660 Array_Type_Declaration (T, Def);
2662 when N_Derived_Type_Definition =>
2663 Derived_Type_Declaration (T, N, T /= Def_Id);
2665 when N_Enumeration_Type_Definition =>
2666 Enumeration_Type_Declaration (T, Def);
2668 when N_Floating_Point_Definition =>
2669 Floating_Point_Type_Declaration (T, Def);
2671 when N_Decimal_Fixed_Point_Definition =>
2672 Decimal_Fixed_Point_Type_Declaration (T, Def);
2674 when N_Ordinary_Fixed_Point_Definition =>
2675 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2677 when N_Signed_Integer_Type_Definition =>
2678 Signed_Integer_Type_Declaration (T, Def);
2680 when N_Modular_Type_Definition =>
2681 Modular_Type_Declaration (T, Def);
2683 when N_Record_Definition =>
2684 Record_Type_Declaration (T, N, Prev);
2686 -- If declaration has a parse error, nothing to elaborate.
2692 raise Program_Error;
2697 if Etype (T) = Any_Type then
2701 -- Controlled type is not allowed in SPARK
2703 if Is_Visibly_Controlled (T) then
2704 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2707 -- A type declared within a Ghost scope is automatically Ghost
2708 -- (SPARK RM 6.9(2)).
2710 if Comes_From_Source (T) and then Within_Ghost_Scope then
2711 Set_Is_Ghost_Entity (T);
2714 -- Some common processing for all types
2716 Set_Depends_On_Private (T, Has_Private_Component (T));
2717 Check_Ops_From_Incomplete_Type;
2719 -- Both the declared entity, and its anonymous base type if one was
2720 -- created, need freeze nodes allocated.
2723 B : constant Entity_Id := Base_Type (T);
2726 -- In the case where the base type differs from the first subtype, we
2727 -- pre-allocate a freeze node, and set the proper link to the first
2728 -- subtype. Freeze_Entity will use this preallocated freeze node when
2729 -- it freezes the entity.
2731 -- This does not apply if the base type is a generic type, whose
2732 -- declaration is independent of the current derived definition.
2734 if B /= T and then not Is_Generic_Type (B) then
2735 Ensure_Freeze_Node (B);
2736 Set_First_Subtype_Link (Freeze_Node (B), T);
2739 -- A type that is imported through a limited_with clause cannot
2740 -- generate any code, and thus need not be frozen. However, an access
2741 -- type with an imported designated type needs a finalization list,
2742 -- which may be referenced in some other package that has non-limited
2743 -- visibility on the designated type. Thus we must create the
2744 -- finalization list at the point the access type is frozen, to
2745 -- prevent unsatisfied references at link time.
2747 if not From_Limited_With (T) or else Is_Access_Type (T) then
2748 Set_Has_Delayed_Freeze (T);
2752 -- Case where T is the full declaration of some private type which has
2753 -- been swapped in Defining_Identifier (N).
2755 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2756 Process_Full_View (N, T, Def_Id);
2758 -- Record the reference. The form of this is a little strange, since
2759 -- the full declaration has been swapped in. So the first parameter
2760 -- here represents the entity to which a reference is made which is
2761 -- the "real" entity, i.e. the one swapped in, and the second
2762 -- parameter provides the reference location.
2764 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2765 -- since we don't want a complaint about the full type being an
2766 -- unwanted reference to the private type
2769 B : constant Boolean := Has_Pragma_Unreferenced (T);
2771 Set_Has_Pragma_Unreferenced (T, False);
2772 Generate_Reference (T, T, 'c');
2773 Set_Has_Pragma_Unreferenced (T, B);
2776 Set_Completion_Referenced (Def_Id);
2778 -- For completion of incomplete type, process incomplete dependents
2779 -- and always mark the full type as referenced (it is the incomplete
2780 -- type that we get for any real reference).
2782 elsif Ekind (Prev) = E_Incomplete_Type then
2783 Process_Incomplete_Dependents (N, T, Prev);
2784 Generate_Reference (Prev, Def_Id, 'c');
2785 Set_Completion_Referenced (Def_Id);
2787 -- If not private type or incomplete type completion, this is a real
2788 -- definition of a new entity, so record it.
2791 Generate_Definition (Def_Id);
2794 if Chars (Scope (Def_Id)) = Name_System
2795 and then Chars (Def_Id) = Name_Address
2796 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2798 Set_Is_Descendent_Of_Address (Def_Id);
2799 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2800 Set_Is_Descendent_Of_Address (Prev);
2803 Set_Optimize_Alignment_Flags (Def_Id);
2804 Check_Eliminated (Def_Id);
2806 -- If the declaration is a completion and aspects are present, apply
2807 -- them to the entity for the type which is currently the partial
2808 -- view, but which is the one that will be frozen.
2810 if Has_Aspects (N) then
2812 -- In most cases the partial view is a private type, and both views
2813 -- appear in different declarative parts. In the unusual case where
2814 -- the partial view is incomplete, perform the analysis on the
2815 -- full view, to prevent freezing anomalies with the corresponding
2816 -- class-wide type, which otherwise might be frozen before the
2817 -- dispatch table is built.
2820 and then Ekind (Prev) /= E_Incomplete_Type
2822 Analyze_Aspect_Specifications (N, Prev);
2827 Analyze_Aspect_Specifications (N, Def_Id);
2830 end Analyze_Full_Type_Declaration;
2832 ----------------------------------
2833 -- Analyze_Incomplete_Type_Decl --
2834 ----------------------------------
2836 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2837 F : constant Boolean := Is_Pure (Current_Scope);
2841 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
2843 Generate_Definition (Defining_Identifier (N));
2845 -- Process an incomplete declaration. The identifier must not have been
2846 -- declared already in the scope. However, an incomplete declaration may
2847 -- appear in the private part of a package, for a private type that has
2848 -- already been declared.
2850 -- In this case, the discriminants (if any) must match
2852 T := Find_Type_Name (N);
2854 Set_Ekind (T, E_Incomplete_Type);
2855 Init_Size_Align (T);
2856 Set_Is_First_Subtype (T, True);
2859 -- An incomplete type declared within a Ghost scope is automatically
2860 -- Ghost (SPARK RM 6.9(2)).
2862 if Within_Ghost_Scope then
2863 Set_Is_Ghost_Entity (T);
2866 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2867 -- incomplete types.
2869 if Tagged_Present (N) then
2870 Set_Is_Tagged_Type (T, True);
2871 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2872 Make_Class_Wide_Type (T);
2873 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2878 Set_Stored_Constraint (T, No_Elist);
2880 if Present (Discriminant_Specifications (N)) then
2881 Process_Discriminants (N);
2886 -- If the type has discriminants, non-trivial subtypes may be
2887 -- declared before the full view of the type. The full views of those
2888 -- subtypes will be built after the full view of the type.
2890 Set_Private_Dependents (T, New_Elmt_List);
2892 end Analyze_Incomplete_Type_Decl;
2894 -----------------------------------
2895 -- Analyze_Interface_Declaration --
2896 -----------------------------------
2898 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2899 CW : constant Entity_Id := Class_Wide_Type (T);
2902 Set_Is_Tagged_Type (T);
2903 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2905 Set_Is_Limited_Record (T, Limited_Present (Def)
2906 or else Task_Present (Def)
2907 or else Protected_Present (Def)
2908 or else Synchronized_Present (Def));
2910 -- Type is abstract if full declaration carries keyword, or if previous
2911 -- partial view did.
2913 Set_Is_Abstract_Type (T);
2914 Set_Is_Interface (T);
2916 -- Type is a limited interface if it includes the keyword limited, task,
2917 -- protected, or synchronized.
2919 Set_Is_Limited_Interface
2920 (T, Limited_Present (Def)
2921 or else Protected_Present (Def)
2922 or else Synchronized_Present (Def)
2923 or else Task_Present (Def));
2925 Set_Interfaces (T, New_Elmt_List);
2926 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2928 -- Complete the decoration of the class-wide entity if it was already
2929 -- built (i.e. during the creation of the limited view)
2931 if Present (CW) then
2932 Set_Is_Interface (CW);
2933 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2936 -- Check runtime support for synchronized interfaces
2938 if VM_Target = No_VM
2939 and then (Is_Task_Interface (T)
2940 or else Is_Protected_Interface (T)
2941 or else Is_Synchronized_Interface (T))
2942 and then not RTE_Available (RE_Select_Specific_Data)
2944 Error_Msg_CRT ("synchronized interfaces", T);
2946 end Analyze_Interface_Declaration;
2948 -----------------------------
2949 -- Analyze_Itype_Reference --
2950 -----------------------------
2952 -- Nothing to do. This node is placed in the tree only for the benefit of
2953 -- back end processing, and has no effect on the semantic processing.
2955 procedure Analyze_Itype_Reference (N : Node_Id) is
2957 pragma Assert (Is_Itype (Itype (N)));
2959 end Analyze_Itype_Reference;
2961 --------------------------------
2962 -- Analyze_Number_Declaration --
2963 --------------------------------
2965 procedure Analyze_Number_Declaration (N : Node_Id) is
2966 Id : constant Entity_Id := Defining_Identifier (N);
2967 E : constant Node_Id := Expression (N);
2969 Index : Interp_Index;
2973 Generate_Definition (Id);
2976 -- A number declared within a Ghost scope is automatically Ghost
2977 -- (SPARK RM 6.9(2)).
2979 if Within_Ghost_Scope then
2980 Set_Is_Ghost_Entity (Id);
2983 -- This is an optimization of a common case of an integer literal
2985 if Nkind (E) = N_Integer_Literal then
2986 Set_Is_Static_Expression (E, True);
2987 Set_Etype (E, Universal_Integer);
2989 Set_Etype (Id, Universal_Integer);
2990 Set_Ekind (Id, E_Named_Integer);
2991 Set_Is_Frozen (Id, True);
2995 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2997 -- Process expression, replacing error by integer zero, to avoid
2998 -- cascaded errors or aborts further along in the processing
3000 -- Replace Error by integer zero, which seems least likely to cause
3004 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3005 Set_Error_Posted (E);
3010 -- Verify that the expression is static and numeric. If
3011 -- the expression is overloaded, we apply the preference
3012 -- rule that favors root numeric types.
3014 if not Is_Overloaded (E) then
3016 if Has_Dynamic_Predicate_Aspect (T) then
3018 ("subtype has dynamic predicate, "
3019 & "not allowed in number declaration", N);
3025 Get_First_Interp (E, Index, It);
3026 while Present (It.Typ) loop
3027 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3028 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3030 if T = Any_Type then
3033 elsif It.Typ = Universal_Real
3035 It.Typ = Universal_Integer
3037 -- Choose universal interpretation over any other
3044 Get_Next_Interp (Index, It);
3048 if Is_Integer_Type (T) then
3050 Set_Etype (Id, Universal_Integer);
3051 Set_Ekind (Id, E_Named_Integer);
3053 elsif Is_Real_Type (T) then
3055 -- Because the real value is converted to universal_real, this is a
3056 -- legal context for a universal fixed expression.
3058 if T = Universal_Fixed then
3060 Loc : constant Source_Ptr := Sloc (N);
3061 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3063 New_Occurrence_Of (Universal_Real, Loc),
3064 Expression => Relocate_Node (E));
3071 elsif T = Any_Fixed then
3072 Error_Msg_N ("illegal context for mixed mode operation", E);
3074 -- Expression is of the form : universal_fixed * integer. Try to
3075 -- resolve as universal_real.
3077 T := Universal_Real;
3082 Set_Etype (Id, Universal_Real);
3083 Set_Ekind (Id, E_Named_Real);
3086 Wrong_Type (E, Any_Numeric);
3090 Set_Ekind (Id, E_Constant);
3091 Set_Never_Set_In_Source (Id, True);
3092 Set_Is_True_Constant (Id, True);
3096 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3097 Set_Etype (E, Etype (Id));
3100 if not Is_OK_Static_Expression (E) then
3101 Flag_Non_Static_Expr
3102 ("non-static expression used in number declaration!", E);
3103 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3104 Set_Etype (E, Any_Type);
3106 end Analyze_Number_Declaration;
3108 -----------------------------
3109 -- Analyze_Object_Contract --
3110 -----------------------------
3112 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3113 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3114 AR_Val : Boolean := False;
3115 AW_Val : Boolean := False;
3116 ER_Val : Boolean := False;
3117 EW_Val : Boolean := False;
3119 Seen : Boolean := False;
3122 -- The loop parameter in an element iterator over a formal container
3123 -- is declared with an object declaration but no contracts apply.
3125 if Ekind (Obj_Id) = E_Loop_Parameter then
3129 if Ekind (Obj_Id) = E_Constant then
3131 -- A constant cannot be effectively volatile. This check is only
3132 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3133 -- rule. Do not flag internally-generated constants that map generic
3134 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3137 and then Is_Effectively_Volatile (Obj_Id)
3138 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3140 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3143 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3145 -- The following checks are only relevant when SPARK_Mode is on as
3146 -- they are not standard Ada legality rules. Internally generated
3147 -- temporaries are ignored.
3149 if SPARK_Mode = On and then Comes_From_Source (Obj_Id) then
3150 if Is_Effectively_Volatile (Obj_Id) then
3152 -- The declaration of an effectively volatile object must
3153 -- appear at the library level (SPARK RM 7.1.3(7), C.6(6)).
3155 if not Is_Library_Level_Entity (Obj_Id) then
3157 ("volatile variable & must be declared at library level",
3160 -- An object of a discriminated type cannot be effectively
3161 -- volatile (SPARK RM C.6(4)).
3163 elsif Has_Discriminants (Obj_Typ) then
3165 ("discriminated object & cannot be volatile", Obj_Id);
3167 -- An object of a tagged type cannot be effectively volatile
3168 -- (SPARK RM C.6(5)).
3170 elsif Is_Tagged_Type (Obj_Typ) then
3171 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3174 -- The object is not effectively volatile
3177 -- A non-effectively volatile object cannot have effectively
3178 -- volatile components (SPARK RM 7.1.3(7)).
3180 if not Is_Effectively_Volatile (Obj_Id)
3181 and then Has_Volatile_Component (Obj_Typ)
3184 ("non-volatile object & cannot have volatile components",
3189 if Is_Ghost_Entity (Obj_Id) then
3191 -- A Ghost object cannot be effectively volatile
3192 -- (SPARK RM 6.9(8)).
3194 if Is_Effectively_Volatile (Obj_Id) then
3195 SPARK_Msg_N ("ghost variable & cannot be volatile", Obj_Id);
3197 -- A Ghost object cannot be imported or exported
3198 -- (SPARK RM 6.9(8)).
3200 elsif Is_Imported (Obj_Id) then
3201 SPARK_Msg_N ("ghost object & cannot be imported", Obj_Id);
3203 elsif Is_Exported (Obj_Id) then
3204 SPARK_Msg_N ("ghost object & cannot be exported", Obj_Id);
3209 -- Analyze all external properties
3211 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3213 if Present (Prag) then
3214 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3218 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3220 if Present (Prag) then
3221 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3225 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3227 if Present (Prag) then
3228 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3232 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3234 if Present (Prag) then
3235 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3239 -- Verify the mutual interaction of the various external properties
3242 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3245 -- Check whether the lack of indicator Part_Of agrees with the
3246 -- placement of the variable with respect to the state space.
3248 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3251 Check_Missing_Part_Of (Obj_Id);
3255 -- A ghost object cannot be imported or exported (SPARK RM 6.9(8))
3257 if Is_Ghost_Entity (Obj_Id) then
3258 if Is_Exported (Obj_Id) then
3259 SPARK_Msg_N ("ghost object & cannot be exported", Obj_Id);
3261 elsif Is_Imported (Obj_Id) then
3262 SPARK_Msg_N ("ghost object & cannot be imported", Obj_Id);
3265 end Analyze_Object_Contract;
3267 --------------------------------
3268 -- Analyze_Object_Declaration --
3269 --------------------------------
3271 procedure Analyze_Object_Declaration (N : Node_Id) is
3272 Loc : constant Source_Ptr := Sloc (N);
3273 Id : constant Entity_Id := Defining_Identifier (N);
3277 E : Node_Id := Expression (N);
3278 -- E is set to Expression (N) throughout this routine. When
3279 -- Expression (N) is modified, E is changed accordingly.
3281 Prev_Entity : Entity_Id := Empty;
3283 function Count_Tasks (T : Entity_Id) return Uint;
3284 -- This function is called when a non-generic library level object of a
3285 -- task type is declared. Its function is to count the static number of
3286 -- tasks declared within the type (it is only called if Has_Tasks is set
3287 -- for T). As a side effect, if an array of tasks with non-static bounds
3288 -- or a variant record type is encountered, Check_Restrictions is called
3289 -- indicating the count is unknown.
3295 function Count_Tasks (T : Entity_Id) return Uint is
3301 if Is_Task_Type (T) then
3304 elsif Is_Record_Type (T) then
3305 if Has_Discriminants (T) then
3306 Check_Restriction (Max_Tasks, N);
3311 C := First_Component (T);
3312 while Present (C) loop
3313 V := V + Count_Tasks (Etype (C));
3320 elsif Is_Array_Type (T) then
3321 X := First_Index (T);
3322 V := Count_Tasks (Component_Type (T));
3323 while Present (X) loop
3326 if not Is_OK_Static_Subtype (C) then
3327 Check_Restriction (Max_Tasks, N);
3330 V := V * (UI_Max (Uint_0,
3331 Expr_Value (Type_High_Bound (C)) -
3332 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3345 -- Start of processing for Analyze_Object_Declaration
3348 -- There are three kinds of implicit types generated by an
3349 -- object declaration:
3351 -- 1. Those generated by the original Object Definition
3353 -- 2. Those generated by the Expression
3355 -- 3. Those used to constrain the Object Definition with the
3356 -- expression constraints when the definition is unconstrained.
3358 -- They must be generated in this order to avoid order of elaboration
3359 -- issues. Thus the first step (after entering the name) is to analyze
3360 -- the object definition.
3362 if Constant_Present (N) then
3363 Prev_Entity := Current_Entity_In_Scope (Id);
3365 if Present (Prev_Entity)
3367 -- If the homograph is an implicit subprogram, it is overridden
3368 -- by the current declaration.
3370 ((Is_Overloadable (Prev_Entity)
3371 and then Is_Inherited_Operation (Prev_Entity))
3373 -- The current object is a discriminal generated for an entry
3374 -- family index. Even though the index is a constant, in this
3375 -- particular context there is no true constant redeclaration.
3376 -- Enter_Name will handle the visibility.
3379 (Is_Discriminal (Id)
3380 and then Ekind (Discriminal_Link (Id)) =
3381 E_Entry_Index_Parameter)
3383 -- The current object is the renaming for a generic declared
3384 -- within the instance.
3387 (Ekind (Prev_Entity) = E_Package
3388 and then Nkind (Parent (Prev_Entity)) =
3389 N_Package_Renaming_Declaration
3390 and then not Comes_From_Source (Prev_Entity)
3392 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3394 Prev_Entity := Empty;
3398 if Present (Prev_Entity) then
3399 Constant_Redeclaration (Id, N, T);
3401 Generate_Reference (Prev_Entity, Id, 'c');
3402 Set_Completion_Referenced (Id);
3404 if Error_Posted (N) then
3406 -- Type mismatch or illegal redeclaration, Do not analyze
3407 -- expression to avoid cascaded errors.
3409 T := Find_Type_Of_Object (Object_Definition (N), N);
3411 Set_Ekind (Id, E_Variable);
3415 -- In the normal case, enter identifier at the start to catch premature
3416 -- usage in the initialization expression.
3419 Generate_Definition (Id);
3422 Mark_Coextensions (N, Object_Definition (N));
3424 T := Find_Type_Of_Object (Object_Definition (N), N);
3426 if Nkind (Object_Definition (N)) = N_Access_Definition
3428 (Access_To_Subprogram_Definition (Object_Definition (N)))
3429 and then Protected_Present
3430 (Access_To_Subprogram_Definition (Object_Definition (N)))
3432 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3435 if Error_Posted (Id) then
3437 Set_Ekind (Id, E_Variable);
3442 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3443 -- out some static checks
3445 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3447 -- In case of aggregates we must also take care of the correct
3448 -- initialization of nested aggregates bug this is done at the
3449 -- point of the analysis of the aggregate (see sem_aggr.adb).
3451 if Present (Expression (N))
3452 and then Nkind (Expression (N)) = N_Aggregate
3458 Save_Typ : constant Entity_Id := Etype (Id);
3460 Set_Etype (Id, T); -- Temp. decoration for static checks
3461 Null_Exclusion_Static_Checks (N);
3462 Set_Etype (Id, Save_Typ);
3467 -- Object is marked pure if it is in a pure scope
3469 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3471 -- If deferred constant, make sure context is appropriate. We detect
3472 -- a deferred constant as a constant declaration with no expression.
3473 -- A deferred constant can appear in a package body if its completion
3474 -- is by means of an interface pragma.
3476 if Constant_Present (N) and then No (E) then
3478 -- A deferred constant may appear in the declarative part of the
3479 -- following constructs:
3483 -- extended return statements
3486 -- subprogram bodies
3489 -- When declared inside a package spec, a deferred constant must be
3490 -- completed by a full constant declaration or pragma Import. In all
3491 -- other cases, the only proper completion is pragma Import. Extended
3492 -- return statements are flagged as invalid contexts because they do
3493 -- not have a declarative part and so cannot accommodate the pragma.
3495 if Ekind (Current_Scope) = E_Return_Statement then
3497 ("invalid context for deferred constant declaration (RM 7.4)",
3500 ("\declaration requires an initialization expression",
3502 Set_Constant_Present (N, False);
3504 -- In Ada 83, deferred constant must be of private type
3506 elsif not Is_Private_Type (T) then
3507 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3509 ("(Ada 83) deferred constant must be private type", N);
3513 -- If not a deferred constant, then the object declaration freezes
3514 -- its type, unless the object is of an anonymous type and has delayed
3515 -- aspects. In that case the type is frozen when the object itself is.
3518 Check_Fully_Declared (T, N);
3520 if Has_Delayed_Aspects (Id)
3521 and then Is_Array_Type (T)
3522 and then Is_Itype (T)
3524 Set_Has_Delayed_Freeze (T);
3526 Freeze_Before (N, T);
3530 -- If the object was created by a constrained array definition, then
3531 -- set the link in both the anonymous base type and anonymous subtype
3532 -- that are built to represent the array type to point to the object.
3534 if Nkind (Object_Definition (Declaration_Node (Id))) =
3535 N_Constrained_Array_Definition
3537 Set_Related_Array_Object (T, Id);
3538 Set_Related_Array_Object (Base_Type (T), Id);
3541 -- Special checks for protected objects not at library level
3543 if Is_Protected_Type (T)
3544 and then not Is_Library_Level_Entity (Id)
3546 Check_Restriction (No_Local_Protected_Objects, Id);
3548 -- Protected objects with interrupt handlers must be at library level
3550 -- Ada 2005: This test is not needed (and the corresponding clause
3551 -- in the RM is removed) because accessibility checks are sufficient
3552 -- to make handlers not at the library level illegal.
3554 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3555 -- applies to the '95 version of the language as well.
3557 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3559 ("interrupt object can only be declared at library level", Id);
3563 -- The actual subtype of the object is the nominal subtype, unless
3564 -- the nominal one is unconstrained and obtained from the expression.
3568 -- These checks should be performed before the initialization expression
3569 -- is considered, so that the Object_Definition node is still the same
3570 -- as in source code.
3572 -- In SPARK, the nominal subtype is always given by a subtype mark
3573 -- and must not be unconstrained. (The only exception to this is the
3574 -- acceptance of declarations of constants of type String.)
3576 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3578 Check_SPARK_05_Restriction
3579 ("subtype mark required", Object_Definition (N));
3581 elsif Is_Array_Type (T)
3582 and then not Is_Constrained (T)
3583 and then T /= Standard_String
3585 Check_SPARK_05_Restriction
3586 ("subtype mark of constrained type expected",
3587 Object_Definition (N));
3590 -- There are no aliased objects in SPARK
3592 if Aliased_Present (N) then
3593 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3596 -- Process initialization expression if present and not in error
3598 if Present (E) and then E /= Error then
3600 -- Generate an error in case of CPP class-wide object initialization.
3601 -- Required because otherwise the expansion of the class-wide
3602 -- assignment would try to use 'size to initialize the object
3603 -- (primitive that is not available in CPP tagged types).
3605 if Is_Class_Wide_Type (Act_T)
3607 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3609 (Present (Full_View (Root_Type (Etype (Act_T))))
3611 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3614 ("predefined assignment not available for 'C'P'P tagged types",
3618 Mark_Coextensions (N, E);
3621 -- In case of errors detected in the analysis of the expression,
3622 -- decorate it with the expected type to avoid cascaded errors
3624 if No (Etype (E)) then
3628 -- If an initialization expression is present, then we set the
3629 -- Is_True_Constant flag. It will be reset if this is a variable
3630 -- and it is indeed modified.
3632 Set_Is_True_Constant (Id, True);
3634 -- If we are analyzing a constant declaration, set its completion
3635 -- flag after analyzing and resolving the expression.
3637 if Constant_Present (N) then
3638 Set_Has_Completion (Id);
3641 -- Set type and resolve (type may be overridden later on). Note:
3642 -- Ekind (Id) must still be E_Void at this point so that incorrect
3643 -- early usage within E is properly diagnosed.
3647 -- If the expression is an aggregate we must look ahead to detect
3648 -- the possible presence of an address clause, and defer resolution
3649 -- and expansion of the aggregate to the freeze point of the entity.
3651 if Comes_From_Source (N)
3652 and then Expander_Active
3653 and then Present (Following_Address_Clause (N))
3654 and then Nkind (E) = N_Aggregate
3662 -- No further action needed if E is a call to an inlined function
3663 -- which returns an unconstrained type and it has been expanded into
3664 -- a procedure call. In that case N has been replaced by an object
3665 -- declaration without initializing expression and it has been
3666 -- analyzed (see Expand_Inlined_Call).
3668 if Back_End_Inlining
3669 and then Expander_Active
3670 and then Nkind (E) = N_Function_Call
3671 and then Nkind (Name (E)) in N_Has_Entity
3672 and then Is_Inlined (Entity (Name (E)))
3673 and then not Is_Constrained (Etype (E))
3674 and then Analyzed (N)
3675 and then No (Expression (N))
3680 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3681 -- node (which was marked already-analyzed), we need to set the type
3682 -- to something other than Any_Access in order to keep gigi happy.
3684 if Etype (E) = Any_Access then
3688 -- If the object is an access to variable, the initialization
3689 -- expression cannot be an access to constant.
3691 if Is_Access_Type (T)
3692 and then not Is_Access_Constant (T)
3693 and then Is_Access_Type (Etype (E))
3694 and then Is_Access_Constant (Etype (E))
3697 ("access to variable cannot be initialized with an "
3698 & "access-to-constant expression", E);
3701 if not Assignment_OK (N) then
3702 Check_Initialization (T, E);
3705 Check_Unset_Reference (E);
3707 -- If this is a variable, then set current value. If this is a
3708 -- declared constant of a scalar type with a static expression,
3709 -- indicate that it is always valid.
3711 if not Constant_Present (N) then
3712 if Compile_Time_Known_Value (E) then
3713 Set_Current_Value (Id, E);
3716 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3717 Set_Is_Known_Valid (Id);
3720 -- Deal with setting of null flags
3722 if Is_Access_Type (T) then
3723 if Known_Non_Null (E) then
3724 Set_Is_Known_Non_Null (Id, True);
3725 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3726 Set_Is_Known_Null (Id, True);
3730 -- Check incorrect use of dynamically tagged expressions
3732 if Is_Tagged_Type (T) then
3733 Check_Dynamically_Tagged_Expression
3739 Apply_Scalar_Range_Check (E, T);
3740 Apply_Static_Length_Check (E, T);
3742 if Nkind (Original_Node (N)) = N_Object_Declaration
3743 and then Comes_From_Source (Original_Node (N))
3745 -- Only call test if needed
3747 and then Restriction_Check_Required (SPARK_05)
3748 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3750 Check_SPARK_05_Restriction
3751 ("initialization expression is not appropriate", E);
3754 -- A formal parameter of a specific tagged type whose related
3755 -- subprogram is subject to pragma Extensions_Visible with value
3756 -- "False" cannot be implicitly converted to a class-wide type by
3757 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3759 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3761 ("formal parameter with Extensions_Visible False cannot be "
3762 & "implicitly converted to class-wide type", E);
3766 -- If the No_Streams restriction is set, check that the type of the
3767 -- object is not, and does not contain, any subtype derived from
3768 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3769 -- Has_Stream just for efficiency reasons. There is no point in
3770 -- spending time on a Has_Stream check if the restriction is not set.
3772 if Restriction_Check_Required (No_Streams) then
3773 if Has_Stream (T) then
3774 Check_Restriction (No_Streams, N);
3778 -- Deal with predicate check before we start to do major rewriting. It
3779 -- is OK to initialize and then check the initialized value, since the
3780 -- object goes out of scope if we get a predicate failure. Note that we
3781 -- do this in the analyzer and not the expander because the analyzer
3782 -- does some substantial rewriting in some cases.
3784 -- We need a predicate check if the type has predicates, and if either
3785 -- there is an initializing expression, or for default initialization
3786 -- when we have at least one case of an explicit default initial value
3787 -- and then this is not an internal declaration whose initialization
3788 -- comes later (as for an aggregate expansion).
3790 if not Suppress_Assignment_Checks (N)
3791 and then Present (Predicate_Function (T))
3792 and then not No_Initialization (N)
3796 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3798 -- If the type has a static predicate and the expression is known at
3799 -- compile time, see if the expression satisfies the predicate.
3802 Check_Expression_Against_Static_Predicate (E, T);
3806 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3809 -- Case of unconstrained type
3811 if Is_Indefinite_Subtype (T) then
3813 -- In SPARK, a declaration of unconstrained type is allowed
3814 -- only for constants of type string.
3816 if Is_String_Type (T) and then not Constant_Present (N) then
3817 Check_SPARK_05_Restriction
3818 ("declaration of object of unconstrained type not allowed", N);
3821 -- Nothing to do in deferred constant case
3823 if Constant_Present (N) and then No (E) then
3826 -- Case of no initialization present
3829 if No_Initialization (N) then
3832 elsif Is_Class_Wide_Type (T) then
3834 ("initialization required in class-wide declaration ", N);
3838 ("unconstrained subtype not allowed (need initialization)",
3839 Object_Definition (N));
3841 if Is_Record_Type (T) and then Has_Discriminants (T) then
3843 ("\provide initial value or explicit discriminant values",
3844 Object_Definition (N));
3847 ("\or give default discriminant values for type&",
3848 Object_Definition (N), T);
3850 elsif Is_Array_Type (T) then
3852 ("\provide initial value or explicit array bounds",
3853 Object_Definition (N));
3857 -- Case of initialization present but in error. Set initial
3858 -- expression as absent (but do not make above complaints)
3860 elsif E = Error then
3861 Set_Expression (N, Empty);
3864 -- Case of initialization present
3867 -- Check restrictions in Ada 83
3869 if not Constant_Present (N) then
3871 -- Unconstrained variables not allowed in Ada 83 mode
3873 if Ada_Version = Ada_83
3874 and then Comes_From_Source (Object_Definition (N))
3877 ("(Ada 83) unconstrained variable not allowed",
3878 Object_Definition (N));
3882 -- Now we constrain the variable from the initializing expression
3884 -- If the expression is an aggregate, it has been expanded into
3885 -- individual assignments. Retrieve the actual type from the
3886 -- expanded construct.
3888 if Is_Array_Type (T)
3889 and then No_Initialization (N)
3890 and then Nkind (Original_Node (E)) = N_Aggregate
3894 -- In case of class-wide interface object declarations we delay
3895 -- the generation of the equivalent record type declarations until
3896 -- its expansion because there are cases in they are not required.
3898 elsif Is_Interface (T) then
3901 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3902 -- we should prevent the generation of another Itype with the
3903 -- same name as the one already generated, or we end up with
3904 -- two identical types in GNATprove.
3906 elsif GNATprove_Mode then
3909 -- If the type is an unchecked union, no subtype can be built from
3910 -- the expression. Rewrite declaration as a renaming, which the
3911 -- back-end can handle properly. This is a rather unusual case,
3912 -- because most unchecked_union declarations have default values
3913 -- for discriminants and are thus not indefinite.
3915 elsif Is_Unchecked_Union (T) then
3916 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3917 Set_Ekind (Id, E_Constant);
3919 Set_Ekind (Id, E_Variable);
3922 -- An object declared within a Ghost scope is automatically
3923 -- Ghost (SPARK RM 6.9(2)).
3925 if Comes_From_Source (Id) and then Within_Ghost_Scope then
3926 Set_Is_Ghost_Entity (Id);
3928 -- The Ghost policy in effect at the point of declaration
3929 -- and at the point of completion must match
3930 -- (SPARK RM 6.9(14)).
3932 if Present (Prev_Entity)
3933 and then Is_Ghost_Entity (Prev_Entity)
3935 Check_Ghost_Completion (Prev_Entity, Id);
3940 Make_Object_Renaming_Declaration (Loc,
3941 Defining_Identifier => Id,
3942 Subtype_Mark => New_Occurrence_Of (T, Loc),
3945 Set_Renamed_Object (Id, E);
3946 Freeze_Before (N, T);
3951 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3952 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3955 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3957 if Aliased_Present (N) then
3958 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3961 Freeze_Before (N, Act_T);
3962 Freeze_Before (N, T);
3965 elsif Is_Array_Type (T)
3966 and then No_Initialization (N)
3967 and then Nkind (Original_Node (E)) = N_Aggregate
3969 if not Is_Entity_Name (Object_Definition (N)) then
3971 Check_Compile_Time_Size (Act_T);
3973 if Aliased_Present (N) then
3974 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3978 -- When the given object definition and the aggregate are specified
3979 -- independently, and their lengths might differ do a length check.
3980 -- This cannot happen if the aggregate is of the form (others =>...)
3982 if not Is_Constrained (T) then
3985 elsif Nkind (E) = N_Raise_Constraint_Error then
3987 -- Aggregate is statically illegal. Place back in declaration
3989 Set_Expression (N, E);
3990 Set_No_Initialization (N, False);
3992 elsif T = Etype (E) then
3995 elsif Nkind (E) = N_Aggregate
3996 and then Present (Component_Associations (E))
3997 and then Present (Choices (First (Component_Associations (E))))
3998 and then Nkind (First
3999 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4004 Apply_Length_Check (E, T);
4007 -- If the type is limited unconstrained with defaulted discriminants and
4008 -- there is no expression, then the object is constrained by the
4009 -- defaults, so it is worthwhile building the corresponding subtype.
4011 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4012 and then not Is_Constrained (T)
4013 and then Has_Discriminants (T)
4016 Act_T := Build_Default_Subtype (T, N);
4018 -- Ada 2005: A limited object may be initialized by means of an
4019 -- aggregate. If the type has default discriminants it has an
4020 -- unconstrained nominal type, Its actual subtype will be obtained
4021 -- from the aggregate, and not from the default discriminants.
4026 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4028 elsif Nkind (E) = N_Function_Call
4029 and then Constant_Present (N)
4030 and then Has_Unconstrained_Elements (Etype (E))
4032 -- The back-end has problems with constants of a discriminated type
4033 -- with defaults, if the initial value is a function call. We
4034 -- generate an intermediate temporary that will receive a reference
4035 -- to the result of the call. The initialization expression then
4036 -- becomes a dereference of that temporary.
4038 Remove_Side_Effects (E);
4040 -- If this is a constant declaration of an unconstrained type and
4041 -- the initialization is an aggregate, we can use the subtype of the
4042 -- aggregate for the declared entity because it is immutable.
4044 elsif not Is_Constrained (T)
4045 and then Has_Discriminants (T)
4046 and then Constant_Present (N)
4047 and then not Has_Unchecked_Union (T)
4048 and then Nkind (E) = N_Aggregate
4053 -- Check No_Wide_Characters restriction
4055 Check_Wide_Character_Restriction (T, Object_Definition (N));
4057 -- Indicate this is not set in source. Certainly true for constants, and
4058 -- true for variables so far (will be reset for a variable if and when
4059 -- we encounter a modification in the source).
4061 Set_Never_Set_In_Source (Id);
4063 -- Now establish the proper kind and type of the object
4065 if Constant_Present (N) then
4066 Set_Ekind (Id, E_Constant);
4067 Set_Is_True_Constant (Id);
4070 Set_Ekind (Id, E_Variable);
4072 -- A variable is set as shared passive if it appears in a shared
4073 -- passive package, and is at the outer level. This is not done for
4074 -- entities generated during expansion, because those are always
4075 -- manipulated locally.
4077 if Is_Shared_Passive (Current_Scope)
4078 and then Is_Library_Level_Entity (Id)
4079 and then Comes_From_Source (Id)
4081 Set_Is_Shared_Passive (Id);
4082 Check_Shared_Var (Id, T, N);
4085 -- Set Has_Initial_Value if initializing expression present. Note
4086 -- that if there is no initializing expression, we leave the state
4087 -- of this flag unchanged (usually it will be False, but notably in
4088 -- the case of exception choice variables, it will already be true).
4091 Set_Has_Initial_Value (Id);
4094 Set_Contract (Id, Make_Contract (Sloc (Id)));
4097 -- Initialize alignment and size and capture alignment setting
4099 Init_Alignment (Id);
4101 Set_Optimize_Alignment_Flags (Id);
4103 -- An object declared within a Ghost scope is automatically Ghost
4104 -- (SPARK RM 6.9(2)). This property is also inherited when its type
4105 -- is Ghost or the previous declaration of the deferred constant is
4108 if Comes_From_Source (Id)
4109 and then (Is_Ghost_Entity (T)
4110 or else (Present (Prev_Entity)
4111 and then Is_Ghost_Entity (Prev_Entity))
4112 or else Within_Ghost_Scope)
4114 Set_Is_Ghost_Entity (Id);
4116 -- The Ghost policy in effect at the point of declaration and at the
4117 -- point of completion must match (SPARK RM 6.9(14)).
4119 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4120 Check_Ghost_Completion (Prev_Entity, Id);
4124 -- Deal with aliased case
4126 if Aliased_Present (N) then
4127 Set_Is_Aliased (Id);
4129 -- If the object is aliased and the type is unconstrained with
4130 -- defaulted discriminants and there is no expression, then the
4131 -- object is constrained by the defaults, so it is worthwhile
4132 -- building the corresponding subtype.
4134 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4135 -- unconstrained, then only establish an actual subtype if the
4136 -- nominal subtype is indefinite. In definite cases the object is
4137 -- unconstrained in Ada 2005.
4140 and then Is_Record_Type (T)
4141 and then not Is_Constrained (T)
4142 and then Has_Discriminants (T)
4143 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
4145 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4149 -- Now we can set the type of the object
4151 Set_Etype (Id, Act_T);
4153 -- Non-constant object is marked to be treated as volatile if type is
4154 -- volatile and we clear the Current_Value setting that may have been
4155 -- set above. Doing so for constants isn't required and might interfere
4156 -- with possible uses of the object as a static expression in contexts
4157 -- incompatible with volatility (e.g. as a case-statement alternative).
4159 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4160 Set_Treat_As_Volatile (Id);
4161 Set_Current_Value (Id, Empty);
4164 -- Deal with controlled types
4166 if Has_Controlled_Component (Etype (Id))
4167 or else Is_Controlled (Etype (Id))
4169 if not Is_Library_Level_Entity (Id) then
4170 Check_Restriction (No_Nested_Finalization, N);
4172 Validate_Controlled_Object (Id);
4176 if Has_Task (Etype (Id)) then
4177 Check_Restriction (No_Tasking, N);
4179 -- Deal with counting max tasks
4181 -- Nothing to do if inside a generic
4183 if Inside_A_Generic then
4186 -- If library level entity, then count tasks
4188 elsif Is_Library_Level_Entity (Id) then
4189 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4191 -- If not library level entity, then indicate we don't know max
4192 -- tasks and also check task hierarchy restriction and blocking
4193 -- operation (since starting a task is definitely blocking).
4196 Check_Restriction (Max_Tasks, N);
4197 Check_Restriction (No_Task_Hierarchy, N);
4198 Check_Potentially_Blocking_Operation (N);
4201 -- A rather specialized test. If we see two tasks being declared
4202 -- of the same type in the same object declaration, and the task
4203 -- has an entry with an address clause, we know that program error
4204 -- will be raised at run time since we can't have two tasks with
4205 -- entries at the same address.
4207 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4212 E := First_Entity (Etype (Id));
4213 while Present (E) loop
4214 if Ekind (E) = E_Entry
4215 and then Present (Get_Attribute_Definition_Clause
4216 (E, Attribute_Address))
4218 Error_Msg_Warn := SPARK_Mode /= On;
4220 ("more than one task with same entry address<<", N);
4221 Error_Msg_N ("\Program_Error [<<", N);
4223 Make_Raise_Program_Error (Loc,
4224 Reason => PE_Duplicated_Entry_Address));
4234 -- Some simple constant-propagation: if the expression is a constant
4235 -- string initialized with a literal, share the literal. This avoids
4239 and then Is_Entity_Name (E)
4240 and then Ekind (Entity (E)) = E_Constant
4241 and then Base_Type (Etype (E)) = Standard_String
4244 Val : constant Node_Id := Constant_Value (Entity (E));
4246 if Present (Val) and then Nkind (Val) = N_String_Literal then
4247 Rewrite (E, New_Copy (Val));
4252 -- Another optimization: if the nominal subtype is unconstrained and
4253 -- the expression is a function call that returns an unconstrained
4254 -- type, rewrite the declaration as a renaming of the result of the
4255 -- call. The exceptions below are cases where the copy is expected,
4256 -- either by the back end (Aliased case) or by the semantics, as for
4257 -- initializing controlled types or copying tags for classwide types.
4260 and then Nkind (E) = N_Explicit_Dereference
4261 and then Nkind (Original_Node (E)) = N_Function_Call
4262 and then not Is_Library_Level_Entity (Id)
4263 and then not Is_Constrained (Underlying_Type (T))
4264 and then not Is_Aliased (Id)
4265 and then not Is_Class_Wide_Type (T)
4266 and then not Is_Controlled (T)
4267 and then not Has_Controlled_Component (Base_Type (T))
4268 and then Expander_Active
4271 Make_Object_Renaming_Declaration (Loc,
4272 Defining_Identifier => Id,
4273 Access_Definition => Empty,
4274 Subtype_Mark => New_Occurrence_Of
4275 (Base_Type (Etype (Id)), Loc),
4278 Set_Renamed_Object (Id, E);
4280 -- Force generation of debugging information for the constant and for
4281 -- the renamed function call.
4283 Set_Debug_Info_Needed (Id);
4284 Set_Debug_Info_Needed (Entity (Prefix (E)));
4287 if Present (Prev_Entity)
4288 and then Is_Frozen (Prev_Entity)
4289 and then not Error_Posted (Id)
4291 Error_Msg_N ("full constant declaration appears too late", N);
4294 Check_Eliminated (Id);
4296 -- Deal with setting In_Private_Part flag if in private part
4298 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4300 Set_In_Private_Part (Id);
4303 -- Check for violation of No_Local_Timing_Events
4305 if Restriction_Check_Required (No_Local_Timing_Events)
4306 and then not Is_Library_Level_Entity (Id)
4307 and then Is_RTE (Etype (Id), RE_Timing_Event)
4309 Check_Restriction (No_Local_Timing_Events, N);
4313 -- Initialize the refined state of a variable here because this is a
4314 -- common destination for legal and illegal object declarations.
4316 if Ekind (Id) = E_Variable then
4317 Set_Encapsulating_State (Id, Empty);
4320 if Has_Aspects (N) then
4321 Analyze_Aspect_Specifications (N, Id);
4324 Analyze_Dimension (N);
4326 -- Verify whether the object declaration introduces an illegal hidden
4327 -- state within a package subject to a null abstract state.
4329 if Ekind (Id) = E_Variable then
4330 Check_No_Hidden_State (Id);
4332 end Analyze_Object_Declaration;
4334 ---------------------------
4335 -- Analyze_Others_Choice --
4336 ---------------------------
4338 -- Nothing to do for the others choice node itself, the semantic analysis
4339 -- of the others choice will occur as part of the processing of the parent
4341 procedure Analyze_Others_Choice (N : Node_Id) is
4342 pragma Warnings (Off, N);
4345 end Analyze_Others_Choice;
4347 -------------------------------------------
4348 -- Analyze_Private_Extension_Declaration --
4349 -------------------------------------------
4351 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4352 T : constant Entity_Id := Defining_Identifier (N);
4353 Indic : constant Node_Id := Subtype_Indication (N);
4354 Parent_Type : Entity_Id;
4355 Parent_Base : Entity_Id;
4358 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4360 if Is_Non_Empty_List (Interface_List (N)) then
4366 Intf := First (Interface_List (N));
4367 while Present (Intf) loop
4368 T := Find_Type_Of_Subtype_Indic (Intf);
4370 Diagnose_Interface (Intf, T);
4376 Generate_Definition (T);
4378 -- For other than Ada 2012, just enter the name in the current scope
4380 if Ada_Version < Ada_2012 then
4383 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4384 -- case of private type that completes an incomplete type.
4391 Prev := Find_Type_Name (N);
4393 pragma Assert (Prev = T
4394 or else (Ekind (Prev) = E_Incomplete_Type
4395 and then Present (Full_View (Prev))
4396 and then Full_View (Prev) = T));
4400 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4401 Parent_Base := Base_Type (Parent_Type);
4403 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4404 Set_Ekind (T, Ekind (Parent_Type));
4405 Set_Etype (T, Any_Type);
4408 elsif not Is_Tagged_Type (Parent_Type) then
4410 ("parent of type extension must be a tagged type ", Indic);
4413 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4414 Error_Msg_N ("premature derivation of incomplete type", Indic);
4417 elsif Is_Concurrent_Type (Parent_Type) then
4419 ("parent type of a private extension cannot be "
4420 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4422 Set_Etype (T, Any_Type);
4423 Set_Ekind (T, E_Limited_Private_Type);
4424 Set_Private_Dependents (T, New_Elmt_List);
4425 Set_Error_Posted (T);
4429 -- Perhaps the parent type should be changed to the class-wide type's
4430 -- specific type in this case to prevent cascading errors ???
4432 if Is_Class_Wide_Type (Parent_Type) then
4434 ("parent of type extension must not be a class-wide type", Indic);
4438 if (not Is_Package_Or_Generic_Package (Current_Scope)
4439 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4440 or else In_Private_Part (Current_Scope)
4443 Error_Msg_N ("invalid context for private extension", N);
4446 -- Set common attributes
4448 Set_Is_Pure (T, Is_Pure (Current_Scope));
4449 Set_Scope (T, Current_Scope);
4450 Set_Ekind (T, E_Record_Type_With_Private);
4451 Init_Size_Align (T);
4452 Set_Default_SSO (T);
4454 Set_Etype (T, Parent_Base);
4455 Set_Has_Task (T, Has_Task (Parent_Base));
4456 Set_Has_Protected (T, Has_Task (Parent_Base));
4458 Set_Convention (T, Convention (Parent_Type));
4459 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4460 Set_Is_First_Subtype (T);
4461 Make_Class_Wide_Type (T);
4463 if Unknown_Discriminants_Present (N) then
4464 Set_Discriminant_Constraint (T, No_Elist);
4467 Build_Derived_Record_Type (N, Parent_Type, T);
4469 -- Propagate inherited invariant information. The new type has
4470 -- invariants, if the parent type has inheritable invariants,
4471 -- and these invariants can in turn be inherited.
4473 if Has_Inheritable_Invariants (Parent_Type) then
4474 Set_Has_Inheritable_Invariants (T);
4475 Set_Has_Invariants (T);
4478 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4479 -- synchronized formal derived type.
4481 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4482 Set_Is_Limited_Record (T);
4484 -- Formal derived type case
4486 if Is_Generic_Type (T) then
4488 -- The parent must be a tagged limited type or a synchronized
4491 if (not Is_Tagged_Type (Parent_Type)
4492 or else not Is_Limited_Type (Parent_Type))
4494 (not Is_Interface (Parent_Type)
4495 or else not Is_Synchronized_Interface (Parent_Type))
4497 Error_Msg_NE ("parent type of & must be tagged limited " &
4498 "or synchronized", N, T);
4501 -- The progenitors (if any) must be limited or synchronized
4504 if Present (Interfaces (T)) then
4507 Iface_Elmt : Elmt_Id;
4510 Iface_Elmt := First_Elmt (Interfaces (T));
4511 while Present (Iface_Elmt) loop
4512 Iface := Node (Iface_Elmt);
4514 if not Is_Limited_Interface (Iface)
4515 and then not Is_Synchronized_Interface (Iface)
4517 Error_Msg_NE ("progenitor & must be limited " &
4518 "or synchronized", N, Iface);
4521 Next_Elmt (Iface_Elmt);
4526 -- Regular derived extension, the parent must be a limited or
4527 -- synchronized interface.
4530 if not Is_Interface (Parent_Type)
4531 or else (not Is_Limited_Interface (Parent_Type)
4532 and then not Is_Synchronized_Interface (Parent_Type))
4535 ("parent type of & must be limited interface", N, T);
4539 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4540 -- extension with a synchronized parent must be explicitly declared
4541 -- synchronized, because the full view will be a synchronized type.
4542 -- This must be checked before the check for limited types below,
4543 -- to ensure that types declared limited are not allowed to extend
4544 -- synchronized interfaces.
4546 elsif Is_Interface (Parent_Type)
4547 and then Is_Synchronized_Interface (Parent_Type)
4548 and then not Synchronized_Present (N)
4551 ("private extension of& must be explicitly synchronized",
4554 elsif Limited_Present (N) then
4555 Set_Is_Limited_Record (T);
4557 if not Is_Limited_Type (Parent_Type)
4559 (not Is_Interface (Parent_Type)
4560 or else not Is_Limited_Interface (Parent_Type))
4562 Error_Msg_NE ("parent type& of limited extension must be limited",
4568 if Has_Aspects (N) then
4569 Analyze_Aspect_Specifications (N, T);
4571 end Analyze_Private_Extension_Declaration;
4573 ---------------------------------
4574 -- Analyze_Subtype_Declaration --
4575 ---------------------------------
4577 procedure Analyze_Subtype_Declaration
4579 Skip : Boolean := False)
4581 Id : constant Entity_Id := Defining_Identifier (N);
4583 R_Checks : Check_Result;
4586 Generate_Definition (Id);
4587 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4588 Init_Size_Align (Id);
4590 -- The following guard condition on Enter_Name is to handle cases where
4591 -- the defining identifier has already been entered into the scope but
4592 -- the declaration as a whole needs to be analyzed.
4594 -- This case in particular happens for derived enumeration types. The
4595 -- derived enumeration type is processed as an inserted enumeration type
4596 -- declaration followed by a rewritten subtype declaration. The defining
4597 -- identifier, however, is entered into the name scope very early in the
4598 -- processing of the original type declaration and therefore needs to be
4599 -- avoided here, when the created subtype declaration is analyzed. (See
4600 -- Build_Derived_Types)
4602 -- This also happens when the full view of a private type is derived
4603 -- type with constraints. In this case the entity has been introduced
4604 -- in the private declaration.
4606 -- Finally this happens in some complex cases when validity checks are
4607 -- enabled, where the same subtype declaration may be analyzed twice.
4608 -- This can happen if the subtype is created by the pre-analysis of
4609 -- an attribute tht gives the range of a loop statement, and the loop
4610 -- itself appears within an if_statement that will be rewritten during
4614 or else (Present (Etype (Id))
4615 and then (Is_Private_Type (Etype (Id))
4616 or else Is_Task_Type (Etype (Id))
4617 or else Is_Rewrite_Substitution (N)))
4621 elsif Current_Entity (Id) = Id then
4628 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4630 -- Class-wide equivalent types of records with unknown discriminants
4631 -- involve the generation of an itype which serves as the private view
4632 -- of a constrained record subtype. In such cases the base type of the
4633 -- current subtype we are processing is the private itype. Use the full
4634 -- of the private itype when decorating various attributes.
4637 and then Is_Private_Type (T)
4638 and then Present (Full_View (T))
4643 -- Inherit common attributes
4645 Set_Is_Volatile (Id, Is_Volatile (T));
4646 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4647 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4648 Set_Convention (Id, Convention (T));
4650 -- If ancestor has predicates then so does the subtype, and in addition
4651 -- we must delay the freeze to properly arrange predicate inheritance.
4653 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4654 -- in which T = ID, so the above tests and assignments do nothing???
4656 if Has_Predicates (T)
4657 or else (Present (Ancestor_Subtype (T))
4658 and then Has_Predicates (Ancestor_Subtype (T)))
4660 Set_Has_Predicates (Id);
4661 Set_Has_Delayed_Freeze (Id);
4664 -- Subtype of Boolean cannot have a constraint in SPARK
4666 if Is_Boolean_Type (T)
4667 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4669 Check_SPARK_05_Restriction
4670 ("subtype of Boolean cannot have constraint", N);
4673 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4675 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4681 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4682 One_Cstr := First (Constraints (Cstr));
4683 while Present (One_Cstr) loop
4685 -- Index or discriminant constraint in SPARK must be a
4689 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4691 Check_SPARK_05_Restriction
4692 ("subtype mark required", One_Cstr);
4694 -- String subtype must have a lower bound of 1 in SPARK.
4695 -- Note that we do not need to test for the non-static case
4696 -- here, since that was already taken care of in
4697 -- Process_Range_Expr_In_Decl.
4699 elsif Base_Type (T) = Standard_String then
4700 Get_Index_Bounds (One_Cstr, Low, High);
4702 if Is_OK_Static_Expression (Low)
4703 and then Expr_Value (Low) /= 1
4705 Check_SPARK_05_Restriction
4706 ("String subtype must have lower bound of 1", N);
4716 -- In the case where there is no constraint given in the subtype
4717 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4718 -- semantic attributes must be established here.
4720 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4721 Set_Etype (Id, Base_Type (T));
4723 -- Subtype of unconstrained array without constraint is not allowed
4726 if Is_Array_Type (T) and then not Is_Constrained (T) then
4727 Check_SPARK_05_Restriction
4728 ("subtype of unconstrained array must have constraint", N);
4733 Set_Ekind (Id, E_Array_Subtype);
4734 Copy_Array_Subtype_Attributes (Id, T);
4736 when Decimal_Fixed_Point_Kind =>
4737 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4738 Set_Digits_Value (Id, Digits_Value (T));
4739 Set_Delta_Value (Id, Delta_Value (T));
4740 Set_Scale_Value (Id, Scale_Value (T));
4741 Set_Small_Value (Id, Small_Value (T));
4742 Set_Scalar_Range (Id, Scalar_Range (T));
4743 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4744 Set_Is_Constrained (Id, Is_Constrained (T));
4745 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4746 Set_RM_Size (Id, RM_Size (T));
4748 when Enumeration_Kind =>
4749 Set_Ekind (Id, E_Enumeration_Subtype);
4750 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4751 Set_Scalar_Range (Id, Scalar_Range (T));
4752 Set_Is_Character_Type (Id, Is_Character_Type (T));
4753 Set_Is_Constrained (Id, Is_Constrained (T));
4754 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4755 Set_RM_Size (Id, RM_Size (T));
4756 Inherit_Predicate_Flags (Id, T);
4758 when Ordinary_Fixed_Point_Kind =>
4759 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4760 Set_Scalar_Range (Id, Scalar_Range (T));
4761 Set_Small_Value (Id, Small_Value (T));
4762 Set_Delta_Value (Id, Delta_Value (T));
4763 Set_Is_Constrained (Id, Is_Constrained (T));
4764 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4765 Set_RM_Size (Id, RM_Size (T));
4768 Set_Ekind (Id, E_Floating_Point_Subtype);
4769 Set_Scalar_Range (Id, Scalar_Range (T));
4770 Set_Digits_Value (Id, Digits_Value (T));
4771 Set_Is_Constrained (Id, Is_Constrained (T));
4773 when Signed_Integer_Kind =>
4774 Set_Ekind (Id, E_Signed_Integer_Subtype);
4775 Set_Scalar_Range (Id, Scalar_Range (T));
4776 Set_Is_Constrained (Id, Is_Constrained (T));
4777 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4778 Set_RM_Size (Id, RM_Size (T));
4779 Inherit_Predicate_Flags (Id, T);
4781 when Modular_Integer_Kind =>
4782 Set_Ekind (Id, E_Modular_Integer_Subtype);
4783 Set_Scalar_Range (Id, Scalar_Range (T));
4784 Set_Is_Constrained (Id, Is_Constrained (T));
4785 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4786 Set_RM_Size (Id, RM_Size (T));
4787 Inherit_Predicate_Flags (Id, T);
4789 when Class_Wide_Kind =>
4790 Set_Ekind (Id, E_Class_Wide_Subtype);
4791 Set_First_Entity (Id, First_Entity (T));
4792 Set_Last_Entity (Id, Last_Entity (T));
4793 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4794 Set_Cloned_Subtype (Id, T);
4795 Set_Is_Tagged_Type (Id, True);
4796 Set_Has_Unknown_Discriminants
4798 Set_No_Tagged_Streams_Pragma
4799 (Id, No_Tagged_Streams_Pragma (T));
4801 if Ekind (T) = E_Class_Wide_Subtype then
4802 Set_Equivalent_Type (Id, Equivalent_Type (T));
4805 when E_Record_Type | E_Record_Subtype =>
4806 Set_Ekind (Id, E_Record_Subtype);
4808 if Ekind (T) = E_Record_Subtype
4809 and then Present (Cloned_Subtype (T))
4811 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4813 Set_Cloned_Subtype (Id, T);
4816 Set_First_Entity (Id, First_Entity (T));
4817 Set_Last_Entity (Id, Last_Entity (T));
4818 Set_Has_Discriminants (Id, Has_Discriminants (T));
4819 Set_Is_Constrained (Id, Is_Constrained (T));
4820 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4821 Set_Has_Implicit_Dereference
4822 (Id, Has_Implicit_Dereference (T));
4823 Set_Has_Unknown_Discriminants
4824 (Id, Has_Unknown_Discriminants (T));
4826 if Has_Discriminants (T) then
4827 Set_Discriminant_Constraint
4828 (Id, Discriminant_Constraint (T));
4829 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4831 elsif Has_Unknown_Discriminants (Id) then
4832 Set_Discriminant_Constraint (Id, No_Elist);
4835 if Is_Tagged_Type (T) then
4836 Set_Is_Tagged_Type (Id, True);
4837 Set_No_Tagged_Streams_Pragma
4838 (Id, No_Tagged_Streams_Pragma (T));
4839 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4840 Set_Direct_Primitive_Operations
4841 (Id, Direct_Primitive_Operations (T));
4842 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4844 if Is_Interface (T) then
4845 Set_Is_Interface (Id);
4846 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4850 when Private_Kind =>
4851 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4852 Set_Has_Discriminants (Id, Has_Discriminants (T));
4853 Set_Is_Constrained (Id, Is_Constrained (T));
4854 Set_First_Entity (Id, First_Entity (T));
4855 Set_Last_Entity (Id, Last_Entity (T));
4856 Set_Private_Dependents (Id, New_Elmt_List);
4857 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4858 Set_Has_Implicit_Dereference
4859 (Id, Has_Implicit_Dereference (T));
4860 Set_Has_Unknown_Discriminants
4861 (Id, Has_Unknown_Discriminants (T));
4862 Set_Known_To_Have_Preelab_Init
4863 (Id, Known_To_Have_Preelab_Init (T));
4865 if Is_Tagged_Type (T) then
4866 Set_Is_Tagged_Type (Id);
4867 Set_No_Tagged_Streams_Pragma (Id,
4868 No_Tagged_Streams_Pragma (T));
4869 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4870 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4871 Set_Direct_Primitive_Operations (Id,
4872 Direct_Primitive_Operations (T));
4875 -- In general the attributes of the subtype of a private type
4876 -- are the attributes of the partial view of parent. However,
4877 -- the full view may be a discriminated type, and the subtype
4878 -- must share the discriminant constraint to generate correct
4879 -- calls to initialization procedures.
4881 if Has_Discriminants (T) then
4882 Set_Discriminant_Constraint
4883 (Id, Discriminant_Constraint (T));
4884 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4886 elsif Present (Full_View (T))
4887 and then Has_Discriminants (Full_View (T))
4889 Set_Discriminant_Constraint
4890 (Id, Discriminant_Constraint (Full_View (T)));
4891 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4893 -- This would seem semantically correct, but apparently
4894 -- generates spurious errors about missing components ???
4896 -- Set_Has_Discriminants (Id);
4899 Prepare_Private_Subtype_Completion (Id, N);
4901 -- If this is the subtype of a constrained private type with
4902 -- discriminants that has got a full view and we also have
4903 -- built a completion just above, show that the completion
4904 -- is a clone of the full view to the back-end.
4906 if Has_Discriminants (T)
4907 and then not Has_Unknown_Discriminants (T)
4908 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4909 and then Present (Full_View (T))
4910 and then Present (Full_View (Id))
4912 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4916 Set_Ekind (Id, E_Access_Subtype);
4917 Set_Is_Constrained (Id, Is_Constrained (T));
4918 Set_Is_Access_Constant
4919 (Id, Is_Access_Constant (T));
4920 Set_Directly_Designated_Type
4921 (Id, Designated_Type (T));
4922 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4924 -- A Pure library_item must not contain the declaration of a
4925 -- named access type, except within a subprogram, generic
4926 -- subprogram, task unit, or protected unit, or if it has
4927 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4929 if Comes_From_Source (Id)
4930 and then In_Pure_Unit
4931 and then not In_Subprogram_Task_Protected_Unit
4932 and then not No_Pool_Assigned (Id)
4935 ("named access types not allowed in pure unit", N);
4938 when Concurrent_Kind =>
4939 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4940 Set_Corresponding_Record_Type (Id,
4941 Corresponding_Record_Type (T));
4942 Set_First_Entity (Id, First_Entity (T));
4943 Set_First_Private_Entity (Id, First_Private_Entity (T));
4944 Set_Has_Discriminants (Id, Has_Discriminants (T));
4945 Set_Is_Constrained (Id, Is_Constrained (T));
4946 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4947 Set_Last_Entity (Id, Last_Entity (T));
4949 if Is_Tagged_Type (T) then
4950 Set_No_Tagged_Streams_Pragma
4951 (Id, No_Tagged_Streams_Pragma (T));
4954 if Has_Discriminants (T) then
4955 Set_Discriminant_Constraint (Id,
4956 Discriminant_Constraint (T));
4957 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4960 when E_Incomplete_Type =>
4961 if Ada_Version >= Ada_2005 then
4963 -- In Ada 2005 an incomplete type can be explicitly tagged:
4964 -- propagate indication.
4966 Set_Ekind (Id, E_Incomplete_Subtype);
4967 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4968 Set_Private_Dependents (Id, New_Elmt_List);
4970 if Is_Tagged_Type (Id) then
4971 Set_No_Tagged_Streams_Pragma
4972 (Id, No_Tagged_Streams_Pragma (T));
4975 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
4976 -- incomplete type visible through a limited with clause.
4978 if From_Limited_With (T)
4979 and then Present (Non_Limited_View (T))
4981 Set_From_Limited_With (Id);
4982 Set_Non_Limited_View (Id, Non_Limited_View (T));
4984 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4985 -- to the private dependents of the original incomplete
4986 -- type for future transformation.
4989 Append_Elmt (Id, Private_Dependents (T));
4992 -- If the subtype name denotes an incomplete type an error
4993 -- was already reported by Process_Subtype.
4996 Set_Etype (Id, Any_Type);
5000 raise Program_Error;
5004 if Etype (Id) = Any_Type then
5008 -- Some common processing on all types
5010 Set_Size_Info (Id, T);
5011 Set_First_Rep_Item (Id, First_Rep_Item (T));
5013 -- If the parent type is a generic actual, so is the subtype. This may
5014 -- happen in a nested instance. Why Comes_From_Source test???
5016 if not Comes_From_Source (N) then
5017 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5022 Set_Is_Immediately_Visible (Id, True);
5023 Set_Depends_On_Private (Id, Has_Private_Component (T));
5024 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5026 if Is_Interface (T) then
5027 Set_Is_Interface (Id);
5030 if Present (Generic_Parent_Type (N))
5032 (Nkind (Parent (Generic_Parent_Type (N))) /=
5033 N_Formal_Type_Declaration
5034 or else Nkind (Formal_Type_Definition
5035 (Parent (Generic_Parent_Type (N)))) /=
5036 N_Formal_Private_Type_Definition)
5038 if Is_Tagged_Type (Id) then
5040 -- If this is a generic actual subtype for a synchronized type,
5041 -- the primitive operations are those of the corresponding record
5042 -- for which there is a separate subtype declaration.
5044 if Is_Concurrent_Type (Id) then
5046 elsif Is_Class_Wide_Type (Id) then
5047 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5049 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5052 elsif Scope (Etype (Id)) /= Standard_Standard then
5053 Derive_Subprograms (Generic_Parent_Type (N), Id);
5057 if Is_Private_Type (T) and then Present (Full_View (T)) then
5058 Conditional_Delay (Id, Full_View (T));
5060 -- The subtypes of components or subcomponents of protected types
5061 -- do not need freeze nodes, which would otherwise appear in the
5062 -- wrong scope (before the freeze node for the protected type). The
5063 -- proper subtypes are those of the subcomponents of the corresponding
5066 elsif Ekind (Scope (Id)) /= E_Protected_Type
5067 and then Present (Scope (Scope (Id))) -- error defense
5068 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5070 Conditional_Delay (Id, T);
5073 -- Check that Constraint_Error is raised for a scalar subtype indication
5074 -- when the lower or upper bound of a non-null range lies outside the
5075 -- range of the type mark.
5077 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5078 if Is_Scalar_Type (Etype (Id))
5079 and then Scalar_Range (Id) /=
5080 Scalar_Range (Etype (Subtype_Mark
5081 (Subtype_Indication (N))))
5085 Etype (Subtype_Mark (Subtype_Indication (N))));
5087 -- In the array case, check compatibility for each index
5089 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5091 -- This really should be a subprogram that finds the indications
5095 Subt_Index : Node_Id := First_Index (Id);
5096 Target_Index : Node_Id :=
5098 (Subtype_Mark (Subtype_Indication (N))));
5099 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5102 while Present (Subt_Index) loop
5103 if ((Nkind (Subt_Index) = N_Identifier
5104 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5105 or else Nkind (Subt_Index) = N_Subtype_Indication)
5107 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5110 Target_Typ : constant Entity_Id :=
5111 Etype (Target_Index);
5115 (Scalar_Range (Etype (Subt_Index)),
5118 Defining_Identifier (N));
5120 -- Reset Has_Dynamic_Range_Check on the subtype to
5121 -- prevent elision of the index check due to a dynamic
5122 -- check generated for a preceding index (needed since
5123 -- Insert_Range_Checks tries to avoid generating
5124 -- redundant checks on a given declaration).
5126 Set_Has_Dynamic_Range_Check (N, False);
5132 Sloc (Defining_Identifier (N)));
5134 -- Record whether this index involved a dynamic check
5137 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5141 Next_Index (Subt_Index);
5142 Next_Index (Target_Index);
5145 -- Finally, mark whether the subtype involves dynamic checks
5147 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5152 -- A type invariant applies to any subtype in its scope, in particular
5153 -- to a generic actual.
5155 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5156 Set_Has_Invariants (Id);
5157 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5160 -- Make sure that generic actual types are properly frozen. The subtype
5161 -- is marked as a generic actual type when the enclosing instance is
5162 -- analyzed, so here we identify the subtype from the tree structure.
5165 and then Is_Generic_Actual_Type (Id)
5166 and then In_Instance
5167 and then not Comes_From_Source (N)
5168 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5169 and then Is_Frozen (T)
5171 Freeze_Before (N, Id);
5174 Set_Optimize_Alignment_Flags (Id);
5175 Check_Eliminated (Id);
5178 if Has_Aspects (N) then
5179 Analyze_Aspect_Specifications (N, Id);
5182 Analyze_Dimension (N);
5183 end Analyze_Subtype_Declaration;
5185 --------------------------------
5186 -- Analyze_Subtype_Indication --
5187 --------------------------------
5189 procedure Analyze_Subtype_Indication (N : Node_Id) is
5190 T : constant Entity_Id := Subtype_Mark (N);
5191 R : constant Node_Id := Range_Expression (Constraint (N));
5198 Set_Etype (N, Etype (R));
5199 Resolve (R, Entity (T));
5201 Set_Error_Posted (R);
5202 Set_Error_Posted (T);
5204 end Analyze_Subtype_Indication;
5206 --------------------------
5207 -- Analyze_Variant_Part --
5208 --------------------------
5210 procedure Analyze_Variant_Part (N : Node_Id) is
5211 Discr_Name : Node_Id;
5212 Discr_Type : Entity_Id;
5214 procedure Process_Variant (A : Node_Id);
5215 -- Analyze declarations for a single variant
5217 package Analyze_Variant_Choices is
5218 new Generic_Analyze_Choices (Process_Variant);
5219 use Analyze_Variant_Choices;
5221 ---------------------
5222 -- Process_Variant --
5223 ---------------------
5225 procedure Process_Variant (A : Node_Id) is
5226 CL : constant Node_Id := Component_List (A);
5228 if not Null_Present (CL) then
5229 Analyze_Declarations (Component_Items (CL));
5231 if Present (Variant_Part (CL)) then
5232 Analyze (Variant_Part (CL));
5235 end Process_Variant;
5237 -- Start of processing for Analyze_Variant_Part
5240 Discr_Name := Name (N);
5241 Analyze (Discr_Name);
5243 -- If Discr_Name bad, get out (prevent cascaded errors)
5245 if Etype (Discr_Name) = Any_Type then
5249 -- Check invalid discriminant in variant part
5251 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5252 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5255 Discr_Type := Etype (Entity (Discr_Name));
5257 if not Is_Discrete_Type (Discr_Type) then
5259 ("discriminant in a variant part must be of a discrete type",
5264 -- Now analyze the choices, which also analyzes the declarations that
5265 -- are associated with each choice.
5267 Analyze_Choices (Variants (N), Discr_Type);
5269 -- Note: we used to instantiate and call Check_Choices here to check
5270 -- that the choices covered the discriminant, but it's too early to do
5271 -- that because of statically predicated subtypes, whose analysis may
5272 -- be deferred to their freeze point which may be as late as the freeze
5273 -- point of the containing record. So this call is now to be found in
5274 -- Freeze_Record_Declaration.
5276 end Analyze_Variant_Part;
5278 ----------------------------
5279 -- Array_Type_Declaration --
5280 ----------------------------
5282 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5283 Component_Def : constant Node_Id := Component_Definition (Def);
5284 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5285 Element_Type : Entity_Id;
5286 Implicit_Base : Entity_Id;
5288 Related_Id : Entity_Id := Empty;
5290 P : constant Node_Id := Parent (Def);
5294 if Nkind (Def) = N_Constrained_Array_Definition then
5295 Index := First (Discrete_Subtype_Definitions (Def));
5297 Index := First (Subtype_Marks (Def));
5300 -- Find proper names for the implicit types which may be public. In case
5301 -- of anonymous arrays we use the name of the first object of that type
5305 Related_Id := Defining_Identifier (P);
5311 while Present (Index) loop
5314 -- Test for odd case of trying to index a type by the type itself
5316 if Is_Entity_Name (Index) and then Entity (Index) = T then
5317 Error_Msg_N ("type& cannot be indexed by itself", Index);
5318 Set_Entity (Index, Standard_Boolean);
5319 Set_Etype (Index, Standard_Boolean);
5322 -- Check SPARK restriction requiring a subtype mark
5324 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5325 Check_SPARK_05_Restriction ("subtype mark required", Index);
5328 -- Add a subtype declaration for each index of private array type
5329 -- declaration whose etype is also private. For example:
5332 -- type Index is private;
5334 -- type Table is array (Index) of ...
5337 -- This is currently required by the expander for the internally
5338 -- generated equality subprogram of records with variant parts in
5339 -- which the etype of some component is such private type.
5341 if Ekind (Current_Scope) = E_Package
5342 and then In_Private_Part (Current_Scope)
5343 and then Has_Private_Declaration (Etype (Index))
5346 Loc : constant Source_Ptr := Sloc (Def);
5351 New_E := Make_Temporary (Loc, 'T');
5352 Set_Is_Internal (New_E);
5355 Make_Subtype_Declaration (Loc,
5356 Defining_Identifier => New_E,
5357 Subtype_Indication =>
5358 New_Occurrence_Of (Etype (Index), Loc));
5360 Insert_Before (Parent (Def), Decl);
5362 Set_Etype (Index, New_E);
5364 -- If the index is a range the Entity attribute is not
5365 -- available. Example:
5368 -- type T is private;
5370 -- type T is new Natural;
5371 -- Table : array (T(1) .. T(10)) of Boolean;
5374 if Nkind (Index) /= N_Range then
5375 Set_Entity (Index, New_E);
5380 Make_Index (Index, P, Related_Id, Nb_Index);
5382 -- Check error of subtype with predicate for index type
5384 Bad_Predicated_Subtype_Use
5385 ("subtype& has predicate, not allowed as index subtype",
5386 Index, Etype (Index));
5388 -- Move to next index
5391 Nb_Index := Nb_Index + 1;
5394 -- Process subtype indication if one is present
5396 if Present (Component_Typ) then
5397 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5399 Set_Etype (Component_Typ, Element_Type);
5401 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5402 Check_SPARK_05_Restriction
5403 ("subtype mark required", Component_Typ);
5406 -- Ada 2005 (AI-230): Access Definition case
5408 else pragma Assert (Present (Access_Definition (Component_Def)));
5410 -- Indicate that the anonymous access type is created by the
5411 -- array type declaration.
5413 Element_Type := Access_Definition
5415 N => Access_Definition (Component_Def));
5416 Set_Is_Local_Anonymous_Access (Element_Type);
5418 -- Propagate the parent. This field is needed if we have to generate
5419 -- the master_id associated with an anonymous access to task type
5420 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5422 Set_Parent (Element_Type, Parent (T));
5424 -- Ada 2005 (AI-230): In case of components that are anonymous access
5425 -- types the level of accessibility depends on the enclosing type
5428 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5430 -- Ada 2005 (AI-254)
5433 CD : constant Node_Id :=
5434 Access_To_Subprogram_Definition
5435 (Access_Definition (Component_Def));
5437 if Present (CD) and then Protected_Present (CD) then
5439 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5444 -- Constrained array case
5447 T := Create_Itype (E_Void, P, Related_Id, 'T');
5450 if Nkind (Def) = N_Constrained_Array_Definition then
5452 -- Establish Implicit_Base as unconstrained base type
5454 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5456 Set_Etype (Implicit_Base, Implicit_Base);
5457 Set_Scope (Implicit_Base, Current_Scope);
5458 Set_Has_Delayed_Freeze (Implicit_Base);
5459 Set_Default_SSO (Implicit_Base);
5461 -- The constrained array type is a subtype of the unconstrained one
5463 Set_Ekind (T, E_Array_Subtype);
5464 Init_Size_Align (T);
5465 Set_Etype (T, Implicit_Base);
5466 Set_Scope (T, Current_Scope);
5467 Set_Is_Constrained (T, True);
5468 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
5469 Set_Has_Delayed_Freeze (T);
5471 -- Complete setup of implicit base type
5473 Set_First_Index (Implicit_Base, First_Index (T));
5474 Set_Component_Type (Implicit_Base, Element_Type);
5475 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5476 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5477 Set_Component_Size (Implicit_Base, Uint_0);
5478 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5479 Set_Has_Controlled_Component
5481 Has_Controlled_Component (Element_Type)
5482 or else Is_Controlled (Element_Type));
5483 Set_Finalize_Storage_Only
5484 (Implicit_Base, Finalize_Storage_Only
5487 -- Unconstrained array case
5490 Set_Ekind (T, E_Array_Type);
5491 Init_Size_Align (T);
5493 Set_Scope (T, Current_Scope);
5494 Set_Component_Size (T, Uint_0);
5495 Set_Is_Constrained (T, False);
5496 Set_First_Index (T, First (Subtype_Marks (Def)));
5497 Set_Has_Delayed_Freeze (T, True);
5498 Set_Has_Task (T, Has_Task (Element_Type));
5499 Set_Has_Protected (T, Has_Protected (Element_Type));
5500 Set_Has_Controlled_Component (T, Has_Controlled_Component
5503 Is_Controlled (Element_Type));
5504 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5506 Set_Default_SSO (T);
5509 -- Common attributes for both cases
5511 Set_Component_Type (Base_Type (T), Element_Type);
5512 Set_Packed_Array_Impl_Type (T, Empty);
5514 if Aliased_Present (Component_Definition (Def)) then
5515 Check_SPARK_05_Restriction
5516 ("aliased is not allowed", Component_Definition (Def));
5517 Set_Has_Aliased_Components (Etype (T));
5520 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5521 -- array type to ensure that objects of this type are initialized.
5523 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5524 Set_Can_Never_Be_Null (T);
5526 if Null_Exclusion_Present (Component_Definition (Def))
5528 -- No need to check itypes because in their case this check was
5529 -- done at their point of creation
5531 and then not Is_Itype (Element_Type)
5534 ("`NOT NULL` not allowed (null already excluded)",
5535 Subtype_Indication (Component_Definition (Def)));
5539 Priv := Private_Component (Element_Type);
5541 if Present (Priv) then
5543 -- Check for circular definitions
5545 if Priv = Any_Type then
5546 Set_Component_Type (Etype (T), Any_Type);
5548 -- There is a gap in the visibility of operations on the composite
5549 -- type only if the component type is defined in a different scope.
5551 elsif Scope (Priv) = Current_Scope then
5554 elsif Is_Limited_Type (Priv) then
5555 Set_Is_Limited_Composite (Etype (T));
5556 Set_Is_Limited_Composite (T);
5558 Set_Is_Private_Composite (Etype (T));
5559 Set_Is_Private_Composite (T);
5563 -- A syntax error in the declaration itself may lead to an empty index
5564 -- list, in which case do a minimal patch.
5566 if No (First_Index (T)) then
5567 Error_Msg_N ("missing index definition in array type declaration", T);
5570 Indexes : constant List_Id :=
5571 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5573 Set_Discrete_Subtype_Definitions (Def, Indexes);
5574 Set_First_Index (T, First (Indexes));
5579 -- Create a concatenation operator for the new type. Internal array
5580 -- types created for packed entities do not need such, they are
5581 -- compatible with the user-defined type.
5583 if Number_Dimensions (T) = 1
5584 and then not Is_Packed_Array_Impl_Type (T)
5586 New_Concatenation_Op (T);
5589 -- In the case of an unconstrained array the parser has already verified
5590 -- that all the indexes are unconstrained but we still need to make sure
5591 -- that the element type is constrained.
5593 if Is_Indefinite_Subtype (Element_Type) then
5595 ("unconstrained element type in array declaration",
5596 Subtype_Indication (Component_Def));
5598 elsif Is_Abstract_Type (Element_Type) then
5600 ("the type of a component cannot be abstract",
5601 Subtype_Indication (Component_Def));
5604 -- There may be an invariant declared for the component type, but
5605 -- the construction of the component invariant checking procedure
5606 -- takes place during expansion.
5607 end Array_Type_Declaration;
5609 ------------------------------------------------------
5610 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5611 ------------------------------------------------------
5613 function Replace_Anonymous_Access_To_Protected_Subprogram
5614 (N : Node_Id) return Entity_Id
5616 Loc : constant Source_Ptr := Sloc (N);
5618 Curr_Scope : constant Scope_Stack_Entry :=
5619 Scope_Stack.Table (Scope_Stack.Last);
5621 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5624 -- Access definition in declaration
5627 -- Object definition or formal definition with an access definition
5630 -- Declaration of anonymous access to subprogram type
5633 -- Original specification in access to subprogram
5638 Set_Is_Internal (Anon);
5641 when N_Component_Declaration |
5642 N_Unconstrained_Array_Definition |
5643 N_Constrained_Array_Definition =>
5644 Comp := Component_Definition (N);
5645 Acc := Access_Definition (Comp);
5647 when N_Discriminant_Specification =>
5648 Comp := Discriminant_Type (N);
5651 when N_Parameter_Specification =>
5652 Comp := Parameter_Type (N);
5655 when N_Access_Function_Definition =>
5656 Comp := Result_Definition (N);
5659 when N_Object_Declaration =>
5660 Comp := Object_Definition (N);
5663 when N_Function_Specification =>
5664 Comp := Result_Definition (N);
5668 raise Program_Error;
5671 Spec := Access_To_Subprogram_Definition (Acc);
5674 Make_Full_Type_Declaration (Loc,
5675 Defining_Identifier => Anon,
5676 Type_Definition => Copy_Separate_Tree (Spec));
5678 Mark_Rewrite_Insertion (Decl);
5680 -- In ASIS mode, analyze the profile on the original node, because
5681 -- the separate copy does not provide enough links to recover the
5682 -- original tree. Analysis is limited to type annotations, within
5683 -- a temporary scope that serves as an anonymous subprogram to collect
5684 -- otherwise useless temporaries and itypes.
5688 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5691 if Nkind (Spec) = N_Access_Function_Definition then
5692 Set_Ekind (Typ, E_Function);
5694 Set_Ekind (Typ, E_Procedure);
5697 Set_Parent (Typ, N);
5698 Set_Scope (Typ, Current_Scope);
5701 Process_Formals (Parameter_Specifications (Spec), Spec);
5703 if Nkind (Spec) = N_Access_Function_Definition then
5705 Def : constant Node_Id := Result_Definition (Spec);
5708 -- The result might itself be an anonymous access type, so
5711 if Nkind (Def) = N_Access_Definition then
5712 if Present (Access_To_Subprogram_Definition (Def)) then
5715 Replace_Anonymous_Access_To_Protected_Subprogram
5718 Find_Type (Subtype_Mark (Def));
5731 -- Insert the new declaration in the nearest enclosing scope. If the
5732 -- node is a body and N is its return type, the declaration belongs in
5733 -- the enclosing scope.
5737 if Nkind (P) = N_Subprogram_Body
5738 and then Nkind (N) = N_Function_Specification
5743 while Present (P) and then not Has_Declarations (P) loop
5747 pragma Assert (Present (P));
5749 if Nkind (P) = N_Package_Specification then
5750 Prepend (Decl, Visible_Declarations (P));
5752 Prepend (Decl, Declarations (P));
5755 -- Replace the anonymous type with an occurrence of the new declaration.
5756 -- In all cases the rewritten node does not have the null-exclusion
5757 -- attribute because (if present) it was already inherited by the
5758 -- anonymous entity (Anon). Thus, in case of components we do not
5759 -- inherit this attribute.
5761 if Nkind (N) = N_Parameter_Specification then
5762 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5763 Set_Etype (Defining_Identifier (N), Anon);
5764 Set_Null_Exclusion_Present (N, False);
5766 elsif Nkind (N) = N_Object_Declaration then
5767 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5768 Set_Etype (Defining_Identifier (N), Anon);
5770 elsif Nkind (N) = N_Access_Function_Definition then
5771 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5773 elsif Nkind (N) = N_Function_Specification then
5774 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5775 Set_Etype (Defining_Unit_Name (N), Anon);
5779 Make_Component_Definition (Loc,
5780 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5783 Mark_Rewrite_Insertion (Comp);
5785 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5789 -- Temporarily remove the current scope (record or subprogram) from
5790 -- the stack to add the new declarations to the enclosing scope.
5792 Scope_Stack.Decrement_Last;
5794 Set_Is_Itype (Anon);
5795 Scope_Stack.Append (Curr_Scope);
5798 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5799 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5801 end Replace_Anonymous_Access_To_Protected_Subprogram;
5803 -------------------------------
5804 -- Build_Derived_Access_Type --
5805 -------------------------------
5807 procedure Build_Derived_Access_Type
5809 Parent_Type : Entity_Id;
5810 Derived_Type : Entity_Id)
5812 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5814 Desig_Type : Entity_Id;
5816 Discr_Con_Elist : Elist_Id;
5817 Discr_Con_El : Elmt_Id;
5821 -- Set the designated type so it is available in case this is an access
5822 -- to a self-referential type, e.g. a standard list type with a next
5823 -- pointer. Will be reset after subtype is built.
5825 Set_Directly_Designated_Type
5826 (Derived_Type, Designated_Type (Parent_Type));
5828 Subt := Process_Subtype (S, N);
5830 if Nkind (S) /= N_Subtype_Indication
5831 and then Subt /= Base_Type (Subt)
5833 Set_Ekind (Derived_Type, E_Access_Subtype);
5836 if Ekind (Derived_Type) = E_Access_Subtype then
5838 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5839 Ibase : constant Entity_Id :=
5840 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5841 Svg_Chars : constant Name_Id := Chars (Ibase);
5842 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5845 Copy_Node (Pbase, Ibase);
5847 Set_Chars (Ibase, Svg_Chars);
5848 Set_Next_Entity (Ibase, Svg_Next_E);
5849 Set_Sloc (Ibase, Sloc (Derived_Type));
5850 Set_Scope (Ibase, Scope (Derived_Type));
5851 Set_Freeze_Node (Ibase, Empty);
5852 Set_Is_Frozen (Ibase, False);
5853 Set_Comes_From_Source (Ibase, False);
5854 Set_Is_First_Subtype (Ibase, False);
5856 Set_Etype (Ibase, Pbase);
5857 Set_Etype (Derived_Type, Ibase);
5861 Set_Directly_Designated_Type
5862 (Derived_Type, Designated_Type (Subt));
5864 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5865 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5866 Set_Size_Info (Derived_Type, Parent_Type);
5867 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5868 Set_Depends_On_Private (Derived_Type,
5869 Has_Private_Component (Derived_Type));
5870 Conditional_Delay (Derived_Type, Subt);
5872 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5873 -- that it is not redundant.
5875 if Null_Exclusion_Present (Type_Definition (N)) then
5876 Set_Can_Never_Be_Null (Derived_Type);
5878 -- What is with the "AND THEN FALSE" here ???
5880 if Can_Never_Be_Null (Parent_Type)
5884 ("`NOT NULL` not allowed (& already excludes null)",
5888 elsif Can_Never_Be_Null (Parent_Type) then
5889 Set_Can_Never_Be_Null (Derived_Type);
5892 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5893 -- the root type for this information.
5895 -- Apply range checks to discriminants for derived record case
5896 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5898 Desig_Type := Designated_Type (Derived_Type);
5899 if Is_Composite_Type (Desig_Type)
5900 and then (not Is_Array_Type (Desig_Type))
5901 and then Has_Discriminants (Desig_Type)
5902 and then Base_Type (Desig_Type) /= Desig_Type
5904 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5905 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5907 Discr := First_Discriminant (Base_Type (Desig_Type));
5908 while Present (Discr_Con_El) loop
5909 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5910 Next_Elmt (Discr_Con_El);
5911 Next_Discriminant (Discr);
5914 end Build_Derived_Access_Type;
5916 ------------------------------
5917 -- Build_Derived_Array_Type --
5918 ------------------------------
5920 procedure Build_Derived_Array_Type
5922 Parent_Type : Entity_Id;
5923 Derived_Type : Entity_Id)
5925 Loc : constant Source_Ptr := Sloc (N);
5926 Tdef : constant Node_Id := Type_Definition (N);
5927 Indic : constant Node_Id := Subtype_Indication (Tdef);
5928 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5929 Implicit_Base : Entity_Id;
5930 New_Indic : Node_Id;
5932 procedure Make_Implicit_Base;
5933 -- If the parent subtype is constrained, the derived type is a subtype
5934 -- of an implicit base type derived from the parent base.
5936 ------------------------
5937 -- Make_Implicit_Base --
5938 ------------------------
5940 procedure Make_Implicit_Base is
5943 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5945 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5946 Set_Etype (Implicit_Base, Parent_Base);
5948 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5949 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5951 Set_Has_Delayed_Freeze (Implicit_Base, True);
5952 end Make_Implicit_Base;
5954 -- Start of processing for Build_Derived_Array_Type
5957 if not Is_Constrained (Parent_Type) then
5958 if Nkind (Indic) /= N_Subtype_Indication then
5959 Set_Ekind (Derived_Type, E_Array_Type);
5961 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5962 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5964 Set_Has_Delayed_Freeze (Derived_Type, True);
5968 Set_Etype (Derived_Type, Implicit_Base);
5971 Make_Subtype_Declaration (Loc,
5972 Defining_Identifier => Derived_Type,
5973 Subtype_Indication =>
5974 Make_Subtype_Indication (Loc,
5975 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5976 Constraint => Constraint (Indic)));
5978 Rewrite (N, New_Indic);
5983 if Nkind (Indic) /= N_Subtype_Indication then
5986 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5987 Set_Etype (Derived_Type, Implicit_Base);
5988 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5991 Error_Msg_N ("illegal constraint on constrained type", Indic);
5995 -- If parent type is not a derived type itself, and is declared in
5996 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5997 -- the new type's concatenation operator since Derive_Subprograms
5998 -- will not inherit the parent's operator. If the parent type is
5999 -- unconstrained, the operator is of the unconstrained base type.
6001 if Number_Dimensions (Parent_Type) = 1
6002 and then not Is_Limited_Type (Parent_Type)
6003 and then not Is_Derived_Type (Parent_Type)
6004 and then not Is_Package_Or_Generic_Package
6005 (Scope (Base_Type (Parent_Type)))
6007 if not Is_Constrained (Parent_Type)
6008 and then Is_Constrained (Derived_Type)
6010 New_Concatenation_Op (Implicit_Base);
6012 New_Concatenation_Op (Derived_Type);
6015 end Build_Derived_Array_Type;
6017 -----------------------------------
6018 -- Build_Derived_Concurrent_Type --
6019 -----------------------------------
6021 procedure Build_Derived_Concurrent_Type
6023 Parent_Type : Entity_Id;
6024 Derived_Type : Entity_Id)
6026 Loc : constant Source_Ptr := Sloc (N);
6028 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6029 Corr_Decl : Node_Id;
6030 Corr_Decl_Needed : Boolean;
6031 -- If the derived type has fewer discriminants than its parent, the
6032 -- corresponding record is also a derived type, in order to account for
6033 -- the bound discriminants. We create a full type declaration for it in
6036 Constraint_Present : constant Boolean :=
6037 Nkind (Subtype_Indication (Type_Definition (N))) =
6038 N_Subtype_Indication;
6040 D_Constraint : Node_Id;
6041 New_Constraint : Elist_Id;
6042 Old_Disc : Entity_Id;
6043 New_Disc : Entity_Id;
6047 Set_Stored_Constraint (Derived_Type, No_Elist);
6048 Corr_Decl_Needed := False;
6051 if Present (Discriminant_Specifications (N))
6052 and then Constraint_Present
6054 Old_Disc := First_Discriminant (Parent_Type);
6055 New_Disc := First (Discriminant_Specifications (N));
6056 while Present (New_Disc) and then Present (Old_Disc) loop
6057 Next_Discriminant (Old_Disc);
6062 if Present (Old_Disc) and then Expander_Active then
6064 -- The new type has fewer discriminants, so we need to create a new
6065 -- corresponding record, which is derived from the corresponding
6066 -- record of the parent, and has a stored constraint that captures
6067 -- the values of the discriminant constraints. The corresponding
6068 -- record is needed only if expander is active and code generation is
6071 -- The type declaration for the derived corresponding record has the
6072 -- same discriminant part and constraints as the current declaration.
6073 -- Copy the unanalyzed tree to build declaration.
6075 Corr_Decl_Needed := True;
6076 New_N := Copy_Separate_Tree (N);
6079 Make_Full_Type_Declaration (Loc,
6080 Defining_Identifier => Corr_Record,
6081 Discriminant_Specifications =>
6082 Discriminant_Specifications (New_N),
6084 Make_Derived_Type_Definition (Loc,
6085 Subtype_Indication =>
6086 Make_Subtype_Indication (Loc,
6089 (Corresponding_Record_Type (Parent_Type), Loc),
6092 (Subtype_Indication (Type_Definition (New_N))))));
6095 -- Copy Storage_Size and Relative_Deadline variables if task case
6097 if Is_Task_Type (Parent_Type) then
6098 Set_Storage_Size_Variable (Derived_Type,
6099 Storage_Size_Variable (Parent_Type));
6100 Set_Relative_Deadline_Variable (Derived_Type,
6101 Relative_Deadline_Variable (Parent_Type));
6104 if Present (Discriminant_Specifications (N)) then
6105 Push_Scope (Derived_Type);
6106 Check_Or_Process_Discriminants (N, Derived_Type);
6108 if Constraint_Present then
6110 Expand_To_Stored_Constraint
6112 Build_Discriminant_Constraints
6114 Subtype_Indication (Type_Definition (N)), True));
6119 elsif Constraint_Present then
6121 -- Build constrained subtype, copying the constraint, and derive
6122 -- from it to create a derived constrained type.
6125 Loc : constant Source_Ptr := Sloc (N);
6126 Anon : constant Entity_Id :=
6127 Make_Defining_Identifier (Loc,
6128 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6133 Make_Subtype_Declaration (Loc,
6134 Defining_Identifier => Anon,
6135 Subtype_Indication =>
6136 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6137 Insert_Before (N, Decl);
6140 Rewrite (Subtype_Indication (Type_Definition (N)),
6141 New_Occurrence_Of (Anon, Loc));
6142 Set_Analyzed (Derived_Type, False);
6148 -- By default, operations and private data are inherited from parent.
6149 -- However, in the presence of bound discriminants, a new corresponding
6150 -- record will be created, see below.
6152 Set_Has_Discriminants
6153 (Derived_Type, Has_Discriminants (Parent_Type));
6154 Set_Corresponding_Record_Type
6155 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6157 -- Is_Constrained is set according the parent subtype, but is set to
6158 -- False if the derived type is declared with new discriminants.
6162 (Is_Constrained (Parent_Type) or else Constraint_Present)
6163 and then not Present (Discriminant_Specifications (N)));
6165 if Constraint_Present then
6166 if not Has_Discriminants (Parent_Type) then
6167 Error_Msg_N ("untagged parent must have discriminants", N);
6169 elsif Present (Discriminant_Specifications (N)) then
6171 -- Verify that new discriminants are used to constrain old ones
6176 (Constraint (Subtype_Indication (Type_Definition (N)))));
6178 Old_Disc := First_Discriminant (Parent_Type);
6180 while Present (D_Constraint) loop
6181 if Nkind (D_Constraint) /= N_Discriminant_Association then
6183 -- Positional constraint. If it is a reference to a new
6184 -- discriminant, it constrains the corresponding old one.
6186 if Nkind (D_Constraint) = N_Identifier then
6187 New_Disc := First_Discriminant (Derived_Type);
6188 while Present (New_Disc) loop
6189 exit when Chars (New_Disc) = Chars (D_Constraint);
6190 Next_Discriminant (New_Disc);
6193 if Present (New_Disc) then
6194 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6198 Next_Discriminant (Old_Disc);
6200 -- if this is a named constraint, search by name for the old
6201 -- discriminants constrained by the new one.
6203 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6205 -- Find new discriminant with that name
6207 New_Disc := First_Discriminant (Derived_Type);
6208 while Present (New_Disc) loop
6210 Chars (New_Disc) = Chars (Expression (D_Constraint));
6211 Next_Discriminant (New_Disc);
6214 if Present (New_Disc) then
6216 -- Verify that new discriminant renames some discriminant
6217 -- of the parent type, and associate the new discriminant
6218 -- with one or more old ones that it renames.
6224 Selector := First (Selector_Names (D_Constraint));
6225 while Present (Selector) loop
6226 Old_Disc := First_Discriminant (Parent_Type);
6227 while Present (Old_Disc) loop
6228 exit when Chars (Old_Disc) = Chars (Selector);
6229 Next_Discriminant (Old_Disc);
6232 if Present (Old_Disc) then
6233 Set_Corresponding_Discriminant
6234 (New_Disc, Old_Disc);
6243 Next (D_Constraint);
6246 New_Disc := First_Discriminant (Derived_Type);
6247 while Present (New_Disc) loop
6248 if No (Corresponding_Discriminant (New_Disc)) then
6250 ("new discriminant& must constrain old one", N, New_Disc);
6253 Subtypes_Statically_Compatible
6255 Etype (Corresponding_Discriminant (New_Disc)))
6258 ("& not statically compatible with parent discriminant",
6262 Next_Discriminant (New_Disc);
6266 elsif Present (Discriminant_Specifications (N)) then
6268 ("missing discriminant constraint in untagged derivation", N);
6271 -- The entity chain of the derived type includes the new discriminants
6272 -- but shares operations with the parent.
6274 if Present (Discriminant_Specifications (N)) then
6275 Old_Disc := First_Discriminant (Parent_Type);
6276 while Present (Old_Disc) loop
6277 if No (Next_Entity (Old_Disc))
6278 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6281 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6285 Next_Discriminant (Old_Disc);
6289 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6290 if Has_Discriminants (Parent_Type) then
6291 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6292 Set_Discriminant_Constraint (
6293 Derived_Type, Discriminant_Constraint (Parent_Type));
6297 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6299 Set_Has_Completion (Derived_Type);
6301 if Corr_Decl_Needed then
6302 Set_Stored_Constraint (Derived_Type, New_Constraint);
6303 Insert_After (N, Corr_Decl);
6304 Analyze (Corr_Decl);
6305 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6307 end Build_Derived_Concurrent_Type;
6309 ------------------------------------
6310 -- Build_Derived_Enumeration_Type --
6311 ------------------------------------
6313 procedure Build_Derived_Enumeration_Type
6315 Parent_Type : Entity_Id;
6316 Derived_Type : Entity_Id)
6318 Loc : constant Source_Ptr := Sloc (N);
6319 Def : constant Node_Id := Type_Definition (N);
6320 Indic : constant Node_Id := Subtype_Indication (Def);
6321 Implicit_Base : Entity_Id;
6322 Literal : Entity_Id;
6323 New_Lit : Entity_Id;
6324 Literals_List : List_Id;
6325 Type_Decl : Node_Id;
6327 Rang_Expr : Node_Id;
6330 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6331 -- not have explicit literals lists we need to process types derived
6332 -- from them specially. This is handled by Derived_Standard_Character.
6333 -- If the parent type is a generic type, there are no literals either,
6334 -- and we construct the same skeletal representation as for the generic
6337 if Is_Standard_Character_Type (Parent_Type) then
6338 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6340 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6346 if Nkind (Indic) /= N_Subtype_Indication then
6348 Make_Attribute_Reference (Loc,
6349 Attribute_Name => Name_First,
6350 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6351 Set_Etype (Lo, Derived_Type);
6354 Make_Attribute_Reference (Loc,
6355 Attribute_Name => Name_Last,
6356 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6357 Set_Etype (Hi, Derived_Type);
6359 Set_Scalar_Range (Derived_Type,
6365 -- Analyze subtype indication and verify compatibility
6366 -- with parent type.
6368 if Base_Type (Process_Subtype (Indic, N)) /=
6369 Base_Type (Parent_Type)
6372 ("illegal constraint for formal discrete type", N);
6378 -- If a constraint is present, analyze the bounds to catch
6379 -- premature usage of the derived literals.
6381 if Nkind (Indic) = N_Subtype_Indication
6382 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6384 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6385 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6388 -- Introduce an implicit base type for the derived type even if there
6389 -- is no constraint attached to it, since this seems closer to the
6390 -- Ada semantics. Build a full type declaration tree for the derived
6391 -- type using the implicit base type as the defining identifier. The
6392 -- build a subtype declaration tree which applies the constraint (if
6393 -- any) have it replace the derived type declaration.
6395 Literal := First_Literal (Parent_Type);
6396 Literals_List := New_List;
6397 while Present (Literal)
6398 and then Ekind (Literal) = E_Enumeration_Literal
6400 -- Literals of the derived type have the same representation as
6401 -- those of the parent type, but this representation can be
6402 -- overridden by an explicit representation clause. Indicate
6403 -- that there is no explicit representation given yet. These
6404 -- derived literals are implicit operations of the new type,
6405 -- and can be overridden by explicit ones.
6407 if Nkind (Literal) = N_Defining_Character_Literal then
6409 Make_Defining_Character_Literal (Loc, Chars (Literal));
6411 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6414 Set_Ekind (New_Lit, E_Enumeration_Literal);
6415 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6416 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6417 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6418 Set_Alias (New_Lit, Literal);
6419 Set_Is_Known_Valid (New_Lit, True);
6421 Append (New_Lit, Literals_List);
6422 Next_Literal (Literal);
6426 Make_Defining_Identifier (Sloc (Derived_Type),
6427 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6429 -- Indicate the proper nature of the derived type. This must be done
6430 -- before analysis of the literals, to recognize cases when a literal
6431 -- may be hidden by a previous explicit function definition (cf.
6434 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6435 Set_Etype (Derived_Type, Implicit_Base);
6438 Make_Full_Type_Declaration (Loc,
6439 Defining_Identifier => Implicit_Base,
6440 Discriminant_Specifications => No_List,
6442 Make_Enumeration_Type_Definition (Loc, Literals_List));
6444 Mark_Rewrite_Insertion (Type_Decl);
6445 Insert_Before (N, Type_Decl);
6446 Analyze (Type_Decl);
6448 -- After the implicit base is analyzed its Etype needs to be changed
6449 -- to reflect the fact that it is derived from the parent type which
6450 -- was ignored during analysis. We also set the size at this point.
6452 Set_Etype (Implicit_Base, Parent_Type);
6454 Set_Size_Info (Implicit_Base, Parent_Type);
6455 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6456 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6458 -- Copy other flags from parent type
6460 Set_Has_Non_Standard_Rep
6461 (Implicit_Base, Has_Non_Standard_Rep
6463 Set_Has_Pragma_Ordered
6464 (Implicit_Base, Has_Pragma_Ordered
6466 Set_Has_Delayed_Freeze (Implicit_Base);
6468 -- Process the subtype indication including a validation check on the
6469 -- constraint, if any. If a constraint is given, its bounds must be
6470 -- implicitly converted to the new type.
6472 if Nkind (Indic) = N_Subtype_Indication then
6474 R : constant Node_Id :=
6475 Range_Expression (Constraint (Indic));
6478 if Nkind (R) = N_Range then
6479 Hi := Build_Scalar_Bound
6480 (High_Bound (R), Parent_Type, Implicit_Base);
6481 Lo := Build_Scalar_Bound
6482 (Low_Bound (R), Parent_Type, Implicit_Base);
6485 -- Constraint is a Range attribute. Replace with explicit
6486 -- mention of the bounds of the prefix, which must be a
6489 Analyze (Prefix (R));
6491 Convert_To (Implicit_Base,
6492 Make_Attribute_Reference (Loc,
6493 Attribute_Name => Name_Last,
6495 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6498 Convert_To (Implicit_Base,
6499 Make_Attribute_Reference (Loc,
6500 Attribute_Name => Name_First,
6502 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6509 (Type_High_Bound (Parent_Type),
6510 Parent_Type, Implicit_Base);
6513 (Type_Low_Bound (Parent_Type),
6514 Parent_Type, Implicit_Base);
6522 -- If we constructed a default range for the case where no range
6523 -- was given, then the expressions in the range must not freeze
6524 -- since they do not correspond to expressions in the source.
6526 if Nkind (Indic) /= N_Subtype_Indication then
6527 Set_Must_Not_Freeze (Lo);
6528 Set_Must_Not_Freeze (Hi);
6529 Set_Must_Not_Freeze (Rang_Expr);
6533 Make_Subtype_Declaration (Loc,
6534 Defining_Identifier => Derived_Type,
6535 Subtype_Indication =>
6536 Make_Subtype_Indication (Loc,
6537 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6539 Make_Range_Constraint (Loc,
6540 Range_Expression => Rang_Expr))));
6544 -- Propagate the aspects from the original type declaration to the
6545 -- declaration of the implicit base.
6547 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6549 -- Apply a range check. Since this range expression doesn't have an
6550 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6553 if Nkind (Indic) = N_Subtype_Indication then
6555 (Range_Expression (Constraint (Indic)), Parent_Type,
6556 Source_Typ => Entity (Subtype_Mark (Indic)));
6559 end Build_Derived_Enumeration_Type;
6561 --------------------------------
6562 -- Build_Derived_Numeric_Type --
6563 --------------------------------
6565 procedure Build_Derived_Numeric_Type
6567 Parent_Type : Entity_Id;
6568 Derived_Type : Entity_Id)
6570 Loc : constant Source_Ptr := Sloc (N);
6571 Tdef : constant Node_Id := Type_Definition (N);
6572 Indic : constant Node_Id := Subtype_Indication (Tdef);
6573 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6574 No_Constraint : constant Boolean := Nkind (Indic) /=
6575 N_Subtype_Indication;
6576 Implicit_Base : Entity_Id;
6582 -- Process the subtype indication including a validation check on
6583 -- the constraint if any.
6585 Discard_Node (Process_Subtype (Indic, N));
6587 -- Introduce an implicit base type for the derived type even if there
6588 -- is no constraint attached to it, since this seems closer to the Ada
6592 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6594 Set_Etype (Implicit_Base, Parent_Base);
6595 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6596 Set_Size_Info (Implicit_Base, Parent_Base);
6597 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6598 Set_Parent (Implicit_Base, Parent (Derived_Type));
6599 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6601 -- Set RM Size for discrete type or decimal fixed-point type
6602 -- Ordinary fixed-point is excluded, why???
6604 if Is_Discrete_Type (Parent_Base)
6605 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6607 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6610 Set_Has_Delayed_Freeze (Implicit_Base);
6612 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6613 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6615 Set_Scalar_Range (Implicit_Base,
6620 if Has_Infinities (Parent_Base) then
6621 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6624 -- The Derived_Type, which is the entity of the declaration, is a
6625 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6626 -- absence of an explicit constraint.
6628 Set_Etype (Derived_Type, Implicit_Base);
6630 -- If we did not have a constraint, then the Ekind is set from the
6631 -- parent type (otherwise Process_Subtype has set the bounds)
6633 if No_Constraint then
6634 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6637 -- If we did not have a range constraint, then set the range from the
6638 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6640 if No_Constraint or else not Has_Range_Constraint (Indic) then
6641 Set_Scalar_Range (Derived_Type,
6643 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6644 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6645 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6647 if Has_Infinities (Parent_Type) then
6648 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6651 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6654 Set_Is_Descendent_Of_Address (Derived_Type,
6655 Is_Descendent_Of_Address (Parent_Type));
6656 Set_Is_Descendent_Of_Address (Implicit_Base,
6657 Is_Descendent_Of_Address (Parent_Type));
6659 -- Set remaining type-specific fields, depending on numeric type
6661 if Is_Modular_Integer_Type (Parent_Type) then
6662 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6664 Set_Non_Binary_Modulus
6665 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6668 (Implicit_Base, Is_Known_Valid (Parent_Base));
6670 elsif Is_Floating_Point_Type (Parent_Type) then
6672 -- Digits of base type is always copied from the digits value of
6673 -- the parent base type, but the digits of the derived type will
6674 -- already have been set if there was a constraint present.
6676 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6677 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6679 if No_Constraint then
6680 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6683 elsif Is_Fixed_Point_Type (Parent_Type) then
6685 -- Small of base type and derived type are always copied from the
6686 -- parent base type, since smalls never change. The delta of the
6687 -- base type is also copied from the parent base type. However the
6688 -- delta of the derived type will have been set already if a
6689 -- constraint was present.
6691 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6692 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6693 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6695 if No_Constraint then
6696 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6699 -- The scale and machine radix in the decimal case are always
6700 -- copied from the parent base type.
6702 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6703 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6704 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6706 Set_Machine_Radix_10
6707 (Derived_Type, Machine_Radix_10 (Parent_Base));
6708 Set_Machine_Radix_10
6709 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6711 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6713 if No_Constraint then
6714 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6717 -- the analysis of the subtype_indication sets the
6718 -- digits value of the derived type.
6725 if Is_Integer_Type (Parent_Type) then
6726 Set_Has_Shift_Operator
6727 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6730 -- The type of the bounds is that of the parent type, and they
6731 -- must be converted to the derived type.
6733 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6735 -- The implicit_base should be frozen when the derived type is frozen,
6736 -- but note that it is used in the conversions of the bounds. For fixed
6737 -- types we delay the determination of the bounds until the proper
6738 -- freezing point. For other numeric types this is rejected by GCC, for
6739 -- reasons that are currently unclear (???), so we choose to freeze the
6740 -- implicit base now. In the case of integers and floating point types
6741 -- this is harmless because subsequent representation clauses cannot
6742 -- affect anything, but it is still baffling that we cannot use the
6743 -- same mechanism for all derived numeric types.
6745 -- There is a further complication: actually some representation
6746 -- clauses can affect the implicit base type. For example, attribute
6747 -- definition clauses for stream-oriented attributes need to set the
6748 -- corresponding TSS entries on the base type, and this normally
6749 -- cannot be done after the base type is frozen, so the circuitry in
6750 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6751 -- and not use Set_TSS in this case.
6753 -- There are also consequences for the case of delayed representation
6754 -- aspects for some cases. For example, a Size aspect is delayed and
6755 -- should not be evaluated to the freeze point. This early freezing
6756 -- means that the size attribute evaluation happens too early???
6758 if Is_Fixed_Point_Type (Parent_Type) then
6759 Conditional_Delay (Implicit_Base, Parent_Type);
6761 Freeze_Before (N, Implicit_Base);
6763 end Build_Derived_Numeric_Type;
6765 --------------------------------
6766 -- Build_Derived_Private_Type --
6767 --------------------------------
6769 procedure Build_Derived_Private_Type
6771 Parent_Type : Entity_Id;
6772 Derived_Type : Entity_Id;
6773 Is_Completion : Boolean;
6774 Derive_Subps : Boolean := True)
6776 Loc : constant Source_Ptr := Sloc (N);
6777 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6778 Par_Scope : constant Entity_Id := Scope (Par_Base);
6779 Full_N : constant Node_Id := New_Copy_Tree (N);
6780 Full_Der : Entity_Id := New_Copy (Derived_Type);
6783 procedure Build_Full_Derivation;
6784 -- Build full derivation, i.e. derive from the full view
6786 procedure Copy_And_Build;
6787 -- Copy derived type declaration, replace parent with its full view,
6788 -- and build derivation
6790 ---------------------------
6791 -- Build_Full_Derivation --
6792 ---------------------------
6794 procedure Build_Full_Derivation is
6796 -- If parent scope is not open, install the declarations
6798 if not In_Open_Scopes (Par_Scope) then
6799 Install_Private_Declarations (Par_Scope);
6800 Install_Visible_Declarations (Par_Scope);
6802 Uninstall_Declarations (Par_Scope);
6804 -- If parent scope is open and in another unit, and parent has a
6805 -- completion, then the derivation is taking place in the visible
6806 -- part of a child unit. In that case retrieve the full view of
6807 -- the parent momentarily.
6809 elsif not In_Same_Source_Unit (N, Parent_Type) then
6810 Full_P := Full_View (Parent_Type);
6811 Exchange_Declarations (Parent_Type);
6813 Exchange_Declarations (Full_P);
6815 -- Otherwise it is a local derivation
6820 end Build_Full_Derivation;
6822 --------------------
6823 -- Copy_And_Build --
6824 --------------------
6826 procedure Copy_And_Build is
6827 Full_Parent : Entity_Id := Parent_Type;
6830 -- If the parent is itself derived from another private type,
6831 -- installing the private declarations has not affected its
6832 -- privacy status, so use its own full view explicitly.
6834 if Is_Private_Type (Full_Parent)
6835 and then Present (Full_View (Full_Parent))
6837 Full_Parent := Full_View (Full_Parent);
6840 -- And its underlying full view if necessary
6842 if Is_Private_Type (Full_Parent)
6843 and then Present (Underlying_Full_View (Full_Parent))
6845 Full_Parent := Underlying_Full_View (Full_Parent);
6848 -- For record, access and most enumeration types, derivation from
6849 -- the full view requires a fully-fledged declaration. In the other
6850 -- cases, just use an itype.
6852 if Ekind (Full_Parent) in Record_Kind
6853 or else Ekind (Full_Parent) in Access_Kind
6855 (Ekind (Full_Parent) in Enumeration_Kind
6856 and then not Is_Standard_Character_Type (Full_Parent)
6857 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6859 -- Copy and adjust declaration to provide a completion for what
6860 -- is originally a private declaration. Indicate that full view
6861 -- is internally generated.
6863 Set_Comes_From_Source (Full_N, False);
6864 Set_Comes_From_Source (Full_Der, False);
6865 Set_Parent (Full_Der, Full_N);
6866 Set_Defining_Identifier (Full_N, Full_Der);
6868 -- If there are no constraints, adjust the subtype mark
6870 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6871 N_Subtype_Indication
6873 Set_Subtype_Indication
6874 (Type_Definition (Full_N),
6875 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6878 Insert_After (N, Full_N);
6880 -- Build full view of derived type from full view of parent which
6881 -- is now installed. Subprograms have been derived on the partial
6882 -- view, the completion does not derive them anew.
6884 if Ekind (Full_Parent) in Record_Kind then
6886 -- If parent type is tagged, the completion inherits the proper
6887 -- primitive operations.
6889 if Is_Tagged_Type (Parent_Type) then
6890 Build_Derived_Record_Type
6891 (Full_N, Full_Parent, Full_Der, Derive_Subps);
6893 Build_Derived_Record_Type
6894 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
6899 (Full_N, Full_Parent, Full_Der,
6900 Is_Completion => False, Derive_Subps => False);
6903 -- The full declaration has been introduced into the tree and
6904 -- processed in the step above. It should not be analyzed again
6905 -- (when encountered later in the current list of declarations)
6906 -- to prevent spurious name conflicts. The full entity remains
6909 Set_Analyzed (Full_N);
6913 Make_Defining_Identifier (Sloc (Derived_Type),
6914 Chars => Chars (Derived_Type));
6915 Set_Is_Itype (Full_Der);
6916 Set_Associated_Node_For_Itype (Full_Der, N);
6917 Set_Parent (Full_Der, N);
6919 (N, Full_Parent, Full_Der,
6920 Is_Completion => False, Derive_Subps => False);
6923 Set_Has_Private_Declaration (Full_Der);
6924 Set_Has_Private_Declaration (Derived_Type);
6926 Set_Scope (Full_Der, Scope (Derived_Type));
6927 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
6928 Set_Has_Size_Clause (Full_Der, False);
6929 Set_Has_Alignment_Clause (Full_Der, False);
6930 Set_Has_Delayed_Freeze (Full_Der);
6931 Set_Is_Frozen (Full_Der, False);
6932 Set_Freeze_Node (Full_Der, Empty);
6933 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
6934 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6936 -- The convention on the base type may be set in the private part
6937 -- and not propagated to the subtype until later, so we obtain the
6938 -- convention from the base type of the parent.
6940 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
6943 -- Start of processing for Build_Derived_Private_Type
6946 if Is_Tagged_Type (Parent_Type) then
6947 Full_P := Full_View (Parent_Type);
6949 -- A type extension of a type with unknown discriminants is an
6950 -- indefinite type that the back-end cannot handle directly.
6951 -- We treat it as a private type, and build a completion that is
6952 -- derived from the full view of the parent, and hopefully has
6953 -- known discriminants.
6955 -- If the full view of the parent type has an underlying record view,
6956 -- use it to generate the underlying record view of this derived type
6957 -- (required for chains of derivations with unknown discriminants).
6959 -- Minor optimization: we avoid the generation of useless underlying
6960 -- record view entities if the private type declaration has unknown
6961 -- discriminants but its corresponding full view has no
6964 if Has_Unknown_Discriminants (Parent_Type)
6965 and then Present (Full_P)
6966 and then (Has_Discriminants (Full_P)
6967 or else Present (Underlying_Record_View (Full_P)))
6968 and then not In_Open_Scopes (Par_Scope)
6969 and then Expander_Active
6972 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6973 New_Ext : constant Node_Id :=
6975 (Record_Extension_Part (Type_Definition (N)));
6979 Build_Derived_Record_Type
6980 (N, Parent_Type, Derived_Type, Derive_Subps);
6982 -- Build anonymous completion, as a derivation from the full
6983 -- view of the parent. This is not a completion in the usual
6984 -- sense, because the current type is not private.
6987 Make_Full_Type_Declaration (Loc,
6988 Defining_Identifier => Full_Der,
6990 Make_Derived_Type_Definition (Loc,
6991 Subtype_Indication =>
6993 (Subtype_Indication (Type_Definition (N))),
6994 Record_Extension_Part => New_Ext));
6996 -- If the parent type has an underlying record view, use it
6997 -- here to build the new underlying record view.
6999 if Present (Underlying_Record_View (Full_P)) then
7001 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7003 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7004 Underlying_Record_View (Full_P));
7007 Install_Private_Declarations (Par_Scope);
7008 Install_Visible_Declarations (Par_Scope);
7009 Insert_Before (N, Decl);
7011 -- Mark entity as an underlying record view before analysis,
7012 -- to avoid generating the list of its primitive operations
7013 -- (which is not really required for this entity) and thus
7014 -- prevent spurious errors associated with missing overriding
7015 -- of abstract primitives (overridden only for Derived_Type).
7017 Set_Ekind (Full_Der, E_Record_Type);
7018 Set_Is_Underlying_Record_View (Full_Der);
7019 Set_Default_SSO (Full_Der);
7023 pragma Assert (Has_Discriminants (Full_Der)
7024 and then not Has_Unknown_Discriminants (Full_Der));
7026 Uninstall_Declarations (Par_Scope);
7028 -- Freeze the underlying record view, to prevent generation of
7029 -- useless dispatching information, which is simply shared with
7030 -- the real derived type.
7032 Set_Is_Frozen (Full_Der);
7034 -- If the derived type has access discriminants, create
7035 -- references to their anonymous types now, to prevent
7036 -- back-end problems when their first use is in generated
7037 -- bodies of primitives.
7043 E := First_Entity (Full_Der);
7045 while Present (E) loop
7046 if Ekind (E) = E_Discriminant
7047 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7049 Build_Itype_Reference (Etype (E), Decl);
7056 -- Set up links between real entity and underlying record view
7058 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7059 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7062 -- If discriminants are known, build derived record
7065 Build_Derived_Record_Type
7066 (N, Parent_Type, Derived_Type, Derive_Subps);
7071 elsif Has_Discriminants (Parent_Type) then
7073 -- Build partial view of derived type from partial view of parent.
7074 -- This must be done before building the full derivation because the
7075 -- second derivation will modify the discriminants of the first and
7076 -- the discriminants are chained with the rest of the components in
7077 -- the full derivation.
7079 Build_Derived_Record_Type
7080 (N, Parent_Type, Derived_Type, Derive_Subps);
7082 -- Build the full derivation if this is not the anonymous derived
7083 -- base type created by Build_Derived_Record_Type in the constrained
7084 -- case (see point 5. of its head comment) since we build it for the
7085 -- derived subtype. And skip it for protected types altogether, as
7086 -- gigi does not use these types directly.
7088 if Present (Full_View (Parent_Type))
7089 and then not Is_Itype (Derived_Type)
7090 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7093 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7095 Last_Discr : Entity_Id;
7098 -- If this is not a completion, construct the implicit full
7099 -- view by deriving from the full view of the parent type.
7100 -- But if this is a completion, the derived private type
7101 -- being built is a full view and the full derivation can
7102 -- only be its underlying full view.
7104 Build_Full_Derivation;
7106 if not Is_Completion then
7107 Set_Full_View (Derived_Type, Full_Der);
7109 Set_Underlying_Full_View (Derived_Type, Full_Der);
7112 if not Is_Base_Type (Derived_Type) then
7113 Set_Full_View (Der_Base, Base_Type (Full_Der));
7116 -- Copy the discriminant list from full view to the partial
7117 -- view (base type and its subtype). Gigi requires that the
7118 -- partial and full views have the same discriminants.
7120 -- Note that since the partial view points to discriminants
7121 -- in the full view, their scope will be that of the full
7122 -- view. This might cause some front end problems and need
7125 Discr := First_Discriminant (Base_Type (Full_Der));
7126 Set_First_Entity (Der_Base, Discr);
7129 Last_Discr := Discr;
7130 Next_Discriminant (Discr);
7131 exit when No (Discr);
7134 Set_Last_Entity (Der_Base, Last_Discr);
7135 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7136 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7138 Set_Stored_Constraint
7139 (Full_Der, Stored_Constraint (Derived_Type));
7143 elsif Present (Full_View (Parent_Type))
7144 and then Has_Discriminants (Full_View (Parent_Type))
7146 if Has_Unknown_Discriminants (Parent_Type)
7147 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7148 N_Subtype_Indication
7151 ("cannot constrain type with unknown discriminants",
7152 Subtype_Indication (Type_Definition (N)));
7156 -- If this is not a completion, construct the implicit full view by
7157 -- deriving from the full view of the parent type. But if this is a
7158 -- completion, the derived private type being built is a full view
7159 -- and the full derivation can only be its underlying full view.
7161 Build_Full_Derivation;
7163 if not Is_Completion then
7164 Set_Full_View (Derived_Type, Full_Der);
7166 Set_Underlying_Full_View (Derived_Type, Full_Der);
7169 -- In any case, the primitive operations are inherited from the
7170 -- parent type, not from the internal full view.
7172 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7174 if Derive_Subps then
7175 Derive_Subprograms (Parent_Type, Derived_Type);
7178 Set_Stored_Constraint (Derived_Type, No_Elist);
7180 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7183 -- Untagged type, No discriminants on either view
7185 if Nkind (Subtype_Indication (Type_Definition (N))) =
7186 N_Subtype_Indication
7189 ("illegal constraint on type without discriminants", N);
7192 if Present (Discriminant_Specifications (N))
7193 and then Present (Full_View (Parent_Type))
7194 and then not Is_Tagged_Type (Full_View (Parent_Type))
7196 Error_Msg_N ("cannot add discriminants to untagged type", N);
7199 Set_Stored_Constraint (Derived_Type, No_Elist);
7200 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7201 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7202 Set_Has_Controlled_Component
7203 (Derived_Type, Has_Controlled_Component
7206 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7208 if not Is_Controlled (Parent_Type) then
7209 Set_Finalize_Storage_Only
7210 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7213 -- If this is not a completion, construct the implicit full view by
7214 -- deriving from the full view of the parent type.
7216 -- ??? If the parent is untagged private and its completion is
7217 -- tagged, this mechanism will not work because we cannot derive from
7218 -- the tagged full view unless we have an extension.
7220 if Present (Full_View (Parent_Type))
7221 and then not Is_Tagged_Type (Full_View (Parent_Type))
7222 and then not Is_Completion
7224 Build_Full_Derivation;
7225 Set_Full_View (Derived_Type, Full_Der);
7229 Set_Has_Unknown_Discriminants (Derived_Type,
7230 Has_Unknown_Discriminants (Parent_Type));
7232 if Is_Private_Type (Derived_Type) then
7233 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7236 -- If the parent base type is in scope, add the derived type to its
7237 -- list of private dependents, because its full view may become
7238 -- visible subsequently (in a nested private part, a body, or in a
7239 -- further child unit).
7241 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7242 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7244 -- Check for unusual case where a type completed by a private
7245 -- derivation occurs within a package nested in a child unit, and
7246 -- the parent is declared in an ancestor.
7248 if Is_Child_Unit (Scope (Current_Scope))
7249 and then Is_Completion
7250 and then In_Private_Part (Current_Scope)
7251 and then Scope (Parent_Type) /= Current_Scope
7253 -- Note that if the parent has a completion in the private part,
7254 -- (which is itself a derivation from some other private type)
7255 -- it is that completion that is visible, there is no full view
7256 -- available, and no special processing is needed.
7258 and then Present (Full_View (Parent_Type))
7260 -- In this case, the full view of the parent type will become
7261 -- visible in the body of the enclosing child, and only then will
7262 -- the current type be possibly non-private. Build an underlying
7263 -- full view that will be installed when the enclosing child body
7266 if Present (Underlying_Full_View (Derived_Type)) then
7267 Full_Der := Underlying_Full_View (Derived_Type);
7269 Build_Full_Derivation;
7270 Set_Underlying_Full_View (Derived_Type, Full_Der);
7273 -- The full view will be used to swap entities on entry/exit to
7274 -- the body, and must appear in the entity list for the package.
7276 Append_Entity (Full_Der, Scope (Derived_Type));
7279 end Build_Derived_Private_Type;
7281 -------------------------------
7282 -- Build_Derived_Record_Type --
7283 -------------------------------
7287 -- Ideally we would like to use the same model of type derivation for
7288 -- tagged and untagged record types. Unfortunately this is not quite
7289 -- possible because the semantics of representation clauses is different
7290 -- for tagged and untagged records under inheritance. Consider the
7293 -- type R (...) is [tagged] record ... end record;
7294 -- type T (...) is new R (...) [with ...];
7296 -- The representation clauses for T can specify a completely different
7297 -- record layout from R's. Hence the same component can be placed in two
7298 -- very different positions in objects of type T and R. If R and T are
7299 -- tagged types, representation clauses for T can only specify the layout
7300 -- of non inherited components, thus components that are common in R and T
7301 -- have the same position in objects of type R and T.
7303 -- This has two implications. The first is that the entire tree for R's
7304 -- declaration needs to be copied for T in the untagged case, so that T
7305 -- can be viewed as a record type of its own with its own representation
7306 -- clauses. The second implication is the way we handle discriminants.
7307 -- Specifically, in the untagged case we need a way to communicate to Gigi
7308 -- what are the real discriminants in the record, while for the semantics
7309 -- we need to consider those introduced by the user to rename the
7310 -- discriminants in the parent type. This is handled by introducing the
7311 -- notion of stored discriminants. See below for more.
7313 -- Fortunately the way regular components are inherited can be handled in
7314 -- the same way in tagged and untagged types.
7316 -- To complicate things a bit more the private view of a private extension
7317 -- cannot be handled in the same way as the full view (for one thing the
7318 -- semantic rules are somewhat different). We will explain what differs
7321 -- 2. DISCRIMINANTS UNDER INHERITANCE
7323 -- The semantic rules governing the discriminants of derived types are
7326 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7327 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7329 -- If parent type has discriminants, then the discriminants that are
7330 -- declared in the derived type are [3.4 (11)]:
7332 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7335 -- o Otherwise, each discriminant of the parent type (implicitly declared
7336 -- in the same order with the same specifications). In this case, the
7337 -- discriminants are said to be "inherited", or if unknown in the parent
7338 -- are also unknown in the derived type.
7340 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7342 -- o The parent subtype must be constrained;
7344 -- o If the parent type is not a tagged type, then each discriminant of
7345 -- the derived type must be used in the constraint defining a parent
7346 -- subtype. [Implementation note: This ensures that the new discriminant
7347 -- can share storage with an existing discriminant.]
7349 -- For the derived type each discriminant of the parent type is either
7350 -- inherited, constrained to equal some new discriminant of the derived
7351 -- type, or constrained to the value of an expression.
7353 -- When inherited or constrained to equal some new discriminant, the
7354 -- parent discriminant and the discriminant of the derived type are said
7357 -- If a discriminant of the parent type is constrained to a specific value
7358 -- in the derived type definition, then the discriminant is said to be
7359 -- "specified" by that derived type definition.
7361 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7363 -- We have spoken about stored discriminants in point 1 (introduction)
7364 -- above. There are two sort of stored discriminants: implicit and
7365 -- explicit. As long as the derived type inherits the same discriminants as
7366 -- the root record type, stored discriminants are the same as regular
7367 -- discriminants, and are said to be implicit. However, if any discriminant
7368 -- in the root type was renamed in the derived type, then the derived
7369 -- type will contain explicit stored discriminants. Explicit stored
7370 -- discriminants are discriminants in addition to the semantically visible
7371 -- discriminants defined for the derived type. Stored discriminants are
7372 -- used by Gigi to figure out what are the physical discriminants in
7373 -- objects of the derived type (see precise definition in einfo.ads).
7374 -- As an example, consider the following:
7376 -- type R (D1, D2, D3 : Int) is record ... end record;
7377 -- type T1 is new R;
7378 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7379 -- type T3 is new T2;
7380 -- type T4 (Y : Int) is new T3 (Y, 99);
7382 -- The following table summarizes the discriminants and stored
7383 -- discriminants in R and T1 through T4.
7385 -- Type Discrim Stored Discrim Comment
7386 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7387 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7388 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7389 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7390 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7392 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7393 -- find the corresponding discriminant in the parent type, while
7394 -- Original_Record_Component (abbreviated ORC below), the actual physical
7395 -- component that is renamed. Finally the field Is_Completely_Hidden
7396 -- (abbreviated ICH below) is set for all explicit stored discriminants
7397 -- (see einfo.ads for more info). For the above example this gives:
7399 -- Discrim CD ORC ICH
7400 -- ^^^^^^^ ^^ ^^^ ^^^
7401 -- D1 in R empty itself no
7402 -- D2 in R empty itself no
7403 -- D3 in R empty itself no
7405 -- D1 in T1 D1 in R itself no
7406 -- D2 in T1 D2 in R itself no
7407 -- D3 in T1 D3 in R itself no
7409 -- X1 in T2 D3 in T1 D3 in T2 no
7410 -- X2 in T2 D1 in T1 D1 in T2 no
7411 -- D1 in T2 empty itself yes
7412 -- D2 in T2 empty itself yes
7413 -- D3 in T2 empty itself yes
7415 -- X1 in T3 X1 in T2 D3 in T3 no
7416 -- X2 in T3 X2 in T2 D1 in T3 no
7417 -- D1 in T3 empty itself yes
7418 -- D2 in T3 empty itself yes
7419 -- D3 in T3 empty itself yes
7421 -- Y in T4 X1 in T3 D3 in T3 no
7422 -- D1 in T3 empty itself yes
7423 -- D2 in T3 empty itself yes
7424 -- D3 in T3 empty itself yes
7426 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7428 -- Type derivation for tagged types is fairly straightforward. If no
7429 -- discriminants are specified by the derived type, these are inherited
7430 -- from the parent. No explicit stored discriminants are ever necessary.
7431 -- The only manipulation that is done to the tree is that of adding a
7432 -- _parent field with parent type and constrained to the same constraint
7433 -- specified for the parent in the derived type definition. For instance:
7435 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7436 -- type T1 is new R with null record;
7437 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7439 -- are changed into:
7441 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7442 -- _parent : R (D1, D2, D3);
7445 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7446 -- _parent : T1 (X2, 88, X1);
7449 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7450 -- ORC and ICH fields are:
7452 -- Discrim CD ORC ICH
7453 -- ^^^^^^^ ^^ ^^^ ^^^
7454 -- D1 in R empty itself no
7455 -- D2 in R empty itself no
7456 -- D3 in R empty itself no
7458 -- D1 in T1 D1 in R D1 in R no
7459 -- D2 in T1 D2 in R D2 in R no
7460 -- D3 in T1 D3 in R D3 in R no
7462 -- X1 in T2 D3 in T1 D3 in R no
7463 -- X2 in T2 D1 in T1 D1 in R no
7465 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7467 -- Regardless of whether we dealing with a tagged or untagged type
7468 -- we will transform all derived type declarations of the form
7470 -- type T is new R (...) [with ...];
7472 -- subtype S is R (...);
7473 -- type T is new S [with ...];
7475 -- type BT is new R [with ...];
7476 -- subtype T is BT (...);
7478 -- That is, the base derived type is constrained only if it has no
7479 -- discriminants. The reason for doing this is that GNAT's semantic model
7480 -- assumes that a base type with discriminants is unconstrained.
7482 -- Note that, strictly speaking, the above transformation is not always
7483 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7485 -- procedure B34011A is
7486 -- type REC (D : integer := 0) is record
7491 -- type T6 is new Rec;
7492 -- function F return T6;
7497 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7500 -- The definition of Q6.U is illegal. However transforming Q6.U into
7502 -- type BaseU is new T6;
7503 -- subtype U is BaseU (Q6.F.I)
7505 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7506 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7507 -- the transformation described above.
7509 -- There is another instance where the above transformation is incorrect.
7513 -- type Base (D : Integer) is tagged null record;
7514 -- procedure P (X : Base);
7516 -- type Der is new Base (2) with null record;
7517 -- procedure P (X : Der);
7520 -- Then the above transformation turns this into
7522 -- type Der_Base is new Base with null record;
7523 -- -- procedure P (X : Base) is implicitly inherited here
7524 -- -- as procedure P (X : Der_Base).
7526 -- subtype Der is Der_Base (2);
7527 -- procedure P (X : Der);
7528 -- -- The overriding of P (X : Der_Base) is illegal since we
7529 -- -- have a parameter conformance problem.
7531 -- To get around this problem, after having semantically processed Der_Base
7532 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7533 -- Discriminant_Constraint from Der so that when parameter conformance is
7534 -- checked when P is overridden, no semantic errors are flagged.
7536 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7538 -- Regardless of whether we are dealing with a tagged or untagged type
7539 -- we will transform all derived type declarations of the form
7541 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7542 -- type T is new R [with ...];
7544 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7546 -- The reason for such transformation is that it allows us to implement a
7547 -- very clean form of component inheritance as explained below.
7549 -- Note that this transformation is not achieved by direct tree rewriting
7550 -- and manipulation, but rather by redoing the semantic actions that the
7551 -- above transformation will entail. This is done directly in routine
7552 -- Inherit_Components.
7554 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7556 -- In both tagged and untagged derived types, regular non discriminant
7557 -- components are inherited in the derived type from the parent type. In
7558 -- the absence of discriminants component, inheritance is straightforward
7559 -- as components can simply be copied from the parent.
7561 -- If the parent has discriminants, inheriting components constrained with
7562 -- these discriminants requires caution. Consider the following example:
7564 -- type R (D1, D2 : Positive) is [tagged] record
7565 -- S : String (D1 .. D2);
7568 -- type T1 is new R [with null record];
7569 -- type T2 (X : positive) is new R (1, X) [with null record];
7571 -- As explained in 6. above, T1 is rewritten as
7572 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7573 -- which makes the treatment for T1 and T2 identical.
7575 -- What we want when inheriting S, is that references to D1 and D2 in R are
7576 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7577 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7578 -- with either discriminant references in the derived type or expressions.
7579 -- This replacement is achieved as follows: before inheriting R's
7580 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7581 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7582 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7583 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7584 -- by String (1 .. X).
7586 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7588 -- We explain here the rules governing private type extensions relevant to
7589 -- type derivation. These rules are explained on the following example:
7591 -- type D [(...)] is new A [(...)] with private; <-- partial view
7592 -- type D [(...)] is new P [(...)] with null record; <-- full view
7594 -- Type A is called the ancestor subtype of the private extension.
7595 -- Type P is the parent type of the full view of the private extension. It
7596 -- must be A or a type derived from A.
7598 -- The rules concerning the discriminants of private type extensions are
7601 -- o If a private extension inherits known discriminants from the ancestor
7602 -- subtype, then the full view must also inherit its discriminants from
7603 -- the ancestor subtype and the parent subtype of the full view must be
7604 -- constrained if and only if the ancestor subtype is constrained.
7606 -- o If a partial view has unknown discriminants, then the full view may
7607 -- define a definite or an indefinite subtype, with or without
7610 -- o If a partial view has neither known nor unknown discriminants, then
7611 -- the full view must define a definite subtype.
7613 -- o If the ancestor subtype of a private extension has constrained
7614 -- discriminants, then the parent subtype of the full view must impose a
7615 -- statically matching constraint on those discriminants.
7617 -- This means that only the following forms of private extensions are
7620 -- type D is new A with private; <-- partial view
7621 -- type D is new P with null record; <-- full view
7623 -- If A has no discriminants than P has no discriminants, otherwise P must
7624 -- inherit A's discriminants.
7626 -- type D is new A (...) with private; <-- partial view
7627 -- type D is new P (:::) with null record; <-- full view
7629 -- P must inherit A's discriminants and (...) and (:::) must statically
7632 -- subtype A is R (...);
7633 -- type D is new A with private; <-- partial view
7634 -- type D is new P with null record; <-- full view
7636 -- P must have inherited R's discriminants and must be derived from A or
7637 -- any of its subtypes.
7639 -- type D (..) is new A with private; <-- partial view
7640 -- type D (..) is new P [(:::)] with null record; <-- full view
7642 -- No specific constraints on P's discriminants or constraint (:::).
7643 -- Note that A can be unconstrained, but the parent subtype P must either
7644 -- be constrained or (:::) must be present.
7646 -- type D (..) is new A [(...)] with private; <-- partial view
7647 -- type D (..) is new P [(:::)] with null record; <-- full view
7649 -- P's constraints on A's discriminants must statically match those
7650 -- imposed by (...).
7652 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7654 -- The full view of a private extension is handled exactly as described
7655 -- above. The model chose for the private view of a private extension is
7656 -- the same for what concerns discriminants (i.e. they receive the same
7657 -- treatment as in the tagged case). However, the private view of the
7658 -- private extension always inherits the components of the parent base,
7659 -- without replacing any discriminant reference. Strictly speaking this is
7660 -- incorrect. However, Gigi never uses this view to generate code so this
7661 -- is a purely semantic issue. In theory, a set of transformations similar
7662 -- to those given in 5. and 6. above could be applied to private views of
7663 -- private extensions to have the same model of component inheritance as
7664 -- for non private extensions. However, this is not done because it would
7665 -- further complicate private type processing. Semantically speaking, this
7666 -- leaves us in an uncomfortable situation. As an example consider:
7669 -- type R (D : integer) is tagged record
7670 -- S : String (1 .. D);
7672 -- procedure P (X : R);
7673 -- type T is new R (1) with private;
7675 -- type T is new R (1) with null record;
7678 -- This is transformed into:
7681 -- type R (D : integer) is tagged record
7682 -- S : String (1 .. D);
7684 -- procedure P (X : R);
7685 -- type T is new R (1) with private;
7687 -- type BaseT is new R with null record;
7688 -- subtype T is BaseT (1);
7691 -- (strictly speaking the above is incorrect Ada)
7693 -- From the semantic standpoint the private view of private extension T
7694 -- should be flagged as constrained since one can clearly have
7698 -- in a unit withing Pack. However, when deriving subprograms for the
7699 -- private view of private extension T, T must be seen as unconstrained
7700 -- since T has discriminants (this is a constraint of the current
7701 -- subprogram derivation model). Thus, when processing the private view of
7702 -- a private extension such as T, we first mark T as unconstrained, we
7703 -- process it, we perform program derivation and just before returning from
7704 -- Build_Derived_Record_Type we mark T as constrained.
7706 -- ??? Are there are other uncomfortable cases that we will have to
7709 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7711 -- Types that are derived from a visible record type and have a private
7712 -- extension present other peculiarities. They behave mostly like private
7713 -- types, but if they have primitive operations defined, these will not
7714 -- have the proper signatures for further inheritance, because other
7715 -- primitive operations will use the implicit base that we define for
7716 -- private derivations below. This affect subprogram inheritance (see
7717 -- Derive_Subprograms for details). We also derive the implicit base from
7718 -- the base type of the full view, so that the implicit base is a record
7719 -- type and not another private type, This avoids infinite loops.
7721 procedure Build_Derived_Record_Type
7723 Parent_Type : Entity_Id;
7724 Derived_Type : Entity_Id;
7725 Derive_Subps : Boolean := True)
7727 function Implements_Ghost_Interface (Typ : Entity_Id) return Boolean;
7728 -- Determine whether type Typ implements at least one Ghost interface
7730 --------------------------------
7731 -- Implements_Ghost_Interface --
7732 --------------------------------
7734 function Implements_Ghost_Interface (Typ : Entity_Id) return Boolean is
7735 Iface_Elmt : Elmt_Id;
7737 -- Traverse the list of interfaces looking for a Ghost interface
7739 if Is_Tagged_Type (Typ) and then Present (Interfaces (Typ)) then
7740 Iface_Elmt := First_Elmt (Interfaces (Typ));
7741 while Present (Iface_Elmt) loop
7742 if Is_Ghost_Entity (Node (Iface_Elmt)) then
7746 Next_Elmt (Iface_Elmt);
7751 end Implements_Ghost_Interface;
7755 Discriminant_Specs : constant Boolean :=
7756 Present (Discriminant_Specifications (N));
7757 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7758 Loc : constant Source_Ptr := Sloc (N);
7759 Private_Extension : constant Boolean :=
7760 Nkind (N) = N_Private_Extension_Declaration;
7761 Assoc_List : Elist_Id;
7762 Constraint_Present : Boolean;
7764 Discrim : Entity_Id;
7766 Inherit_Discrims : Boolean := False;
7767 Last_Discrim : Entity_Id;
7768 New_Base : Entity_Id;
7770 New_Discrs : Elist_Id;
7771 New_Indic : Node_Id;
7772 Parent_Base : Entity_Id;
7773 Save_Etype : Entity_Id;
7774 Save_Discr_Constr : Elist_Id;
7775 Save_Next_Entity : Entity_Id;
7778 Discs : Elist_Id := New_Elmt_List;
7779 -- An empty Discs list means that there were no constraints in the
7780 -- subtype indication or that there was an error processing it.
7782 -- Start of processing for Build_Derived_Record_Type
7785 if Ekind (Parent_Type) = E_Record_Type_With_Private
7786 and then Present (Full_View (Parent_Type))
7787 and then Has_Discriminants (Parent_Type)
7789 Parent_Base := Base_Type (Full_View (Parent_Type));
7791 Parent_Base := Base_Type (Parent_Type);
7794 -- AI05-0115 : if this is a derivation from a private type in some
7795 -- other scope that may lead to invisible components for the derived
7796 -- type, mark it accordingly.
7798 if Is_Private_Type (Parent_Type) then
7799 if Scope (Parent_Type) = Scope (Derived_Type) then
7802 elsif In_Open_Scopes (Scope (Parent_Type))
7803 and then In_Private_Part (Scope (Parent_Type))
7808 Set_Has_Private_Ancestor (Derived_Type);
7812 Set_Has_Private_Ancestor
7813 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7816 -- Before we start the previously documented transformations, here is
7817 -- little fix for size and alignment of tagged types. Normally when we
7818 -- derive type D from type P, we copy the size and alignment of P as the
7819 -- default for D, and in the absence of explicit representation clauses
7820 -- for D, the size and alignment are indeed the same as the parent.
7822 -- But this is wrong for tagged types, since fields may be added, and
7823 -- the default size may need to be larger, and the default alignment may
7824 -- need to be larger.
7826 -- We therefore reset the size and alignment fields in the tagged case.
7827 -- Note that the size and alignment will in any case be at least as
7828 -- large as the parent type (since the derived type has a copy of the
7829 -- parent type in the _parent field)
7831 -- The type is also marked as being tagged here, which is needed when
7832 -- processing components with a self-referential anonymous access type
7833 -- in the call to Check_Anonymous_Access_Components below. Note that
7834 -- this flag is also set later on for completeness.
7837 Set_Is_Tagged_Type (Derived_Type);
7838 Init_Size_Align (Derived_Type);
7841 -- STEP 0a: figure out what kind of derived type declaration we have
7843 if Private_Extension then
7845 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7846 Set_Default_SSO (Derived_Type);
7849 Type_Def := Type_Definition (N);
7851 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7852 -- Parent_Base can be a private type or private extension. However,
7853 -- for tagged types with an extension the newly added fields are
7854 -- visible and hence the Derived_Type is always an E_Record_Type.
7855 -- (except that the parent may have its own private fields).
7856 -- For untagged types we preserve the Ekind of the Parent_Base.
7858 if Present (Record_Extension_Part (Type_Def)) then
7859 Set_Ekind (Derived_Type, E_Record_Type);
7860 Set_Default_SSO (Derived_Type);
7862 -- Create internal access types for components with anonymous
7865 if Ada_Version >= Ada_2005 then
7866 Check_Anonymous_Access_Components
7867 (N, Derived_Type, Derived_Type,
7868 Component_List (Record_Extension_Part (Type_Def)));
7872 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7876 -- Indic can either be an N_Identifier if the subtype indication
7877 -- contains no constraint or an N_Subtype_Indication if the subtype
7878 -- indication has a constraint.
7880 Indic := Subtype_Indication (Type_Def);
7881 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7883 -- Check that the type has visible discriminants. The type may be
7884 -- a private type with unknown discriminants whose full view has
7885 -- discriminants which are invisible.
7887 if Constraint_Present then
7888 if not Has_Discriminants (Parent_Base)
7890 (Has_Unknown_Discriminants (Parent_Base)
7891 and then Is_Private_Type (Parent_Base))
7894 ("invalid constraint: type has no discriminant",
7895 Constraint (Indic));
7897 Constraint_Present := False;
7898 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7900 elsif Is_Constrained (Parent_Type) then
7902 ("invalid constraint: parent type is already constrained",
7903 Constraint (Indic));
7905 Constraint_Present := False;
7906 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7910 -- STEP 0b: If needed, apply transformation given in point 5. above
7912 if not Private_Extension
7913 and then Has_Discriminants (Parent_Type)
7914 and then not Discriminant_Specs
7915 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7917 -- First, we must analyze the constraint (see comment in point 5.)
7918 -- The constraint may come from the subtype indication of the full
7921 if Constraint_Present then
7922 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7924 -- If there is no explicit constraint, there might be one that is
7925 -- inherited from a constrained parent type. In that case verify that
7926 -- it conforms to the constraint in the partial view. In perverse
7927 -- cases the parent subtypes of the partial and full view can have
7928 -- different constraints.
7930 elsif Present (Stored_Constraint (Parent_Type)) then
7931 New_Discrs := Stored_Constraint (Parent_Type);
7934 New_Discrs := No_Elist;
7937 if Has_Discriminants (Derived_Type)
7938 and then Has_Private_Declaration (Derived_Type)
7939 and then Present (Discriminant_Constraint (Derived_Type))
7940 and then Present (New_Discrs)
7942 -- Verify that constraints of the full view statically match
7943 -- those given in the partial view.
7949 C1 := First_Elmt (New_Discrs);
7950 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7951 while Present (C1) and then Present (C2) loop
7952 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7954 (Is_OK_Static_Expression (Node (C1))
7955 and then Is_OK_Static_Expression (Node (C2))
7957 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7962 if Constraint_Present then
7964 ("constraint not conformant to previous declaration",
7968 ("constraint of full view is incompatible "
7969 & "with partial view", N);
7979 -- Insert and analyze the declaration for the unconstrained base type
7981 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7984 Make_Full_Type_Declaration (Loc,
7985 Defining_Identifier => New_Base,
7987 Make_Derived_Type_Definition (Loc,
7988 Abstract_Present => Abstract_Present (Type_Def),
7989 Limited_Present => Limited_Present (Type_Def),
7990 Subtype_Indication =>
7991 New_Occurrence_Of (Parent_Base, Loc),
7992 Record_Extension_Part =>
7993 Relocate_Node (Record_Extension_Part (Type_Def)),
7994 Interface_List => Interface_List (Type_Def)));
7996 Set_Parent (New_Decl, Parent (N));
7997 Mark_Rewrite_Insertion (New_Decl);
7998 Insert_Before (N, New_Decl);
8000 -- In the extension case, make sure ancestor is frozen appropriately
8001 -- (see also non-discriminated case below).
8003 if Present (Record_Extension_Part (Type_Def))
8004 or else Is_Interface (Parent_Base)
8006 Freeze_Before (New_Decl, Parent_Type);
8009 -- Note that this call passes False for the Derive_Subps parameter
8010 -- because subprogram derivation is deferred until after creating
8011 -- the subtype (see below).
8014 (New_Decl, Parent_Base, New_Base,
8015 Is_Completion => False, Derive_Subps => False);
8017 -- ??? This needs re-examination to determine whether the
8018 -- above call can simply be replaced by a call to Analyze.
8020 Set_Analyzed (New_Decl);
8022 -- Insert and analyze the declaration for the constrained subtype
8024 if Constraint_Present then
8026 Make_Subtype_Indication (Loc,
8027 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8028 Constraint => Relocate_Node (Constraint (Indic)));
8032 Constr_List : constant List_Id := New_List;
8037 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8038 while Present (C) loop
8041 -- It is safe here to call New_Copy_Tree since
8042 -- Force_Evaluation was called on each constraint in
8043 -- Build_Discriminant_Constraints.
8045 Append (New_Copy_Tree (Expr), To => Constr_List);
8051 Make_Subtype_Indication (Loc,
8052 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8054 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8059 Make_Subtype_Declaration (Loc,
8060 Defining_Identifier => Derived_Type,
8061 Subtype_Indication => New_Indic));
8065 -- Derivation of subprograms must be delayed until the full subtype
8066 -- has been established, to ensure proper overriding of subprograms
8067 -- inherited by full types. If the derivations occurred as part of
8068 -- the call to Build_Derived_Type above, then the check for type
8069 -- conformance would fail because earlier primitive subprograms
8070 -- could still refer to the full type prior the change to the new
8071 -- subtype and hence would not match the new base type created here.
8072 -- Subprograms are not derived, however, when Derive_Subps is False
8073 -- (since otherwise there could be redundant derivations).
8075 if Derive_Subps then
8076 Derive_Subprograms (Parent_Type, Derived_Type);
8079 -- For tagged types the Discriminant_Constraint of the new base itype
8080 -- is inherited from the first subtype so that no subtype conformance
8081 -- problem arise when the first subtype overrides primitive
8082 -- operations inherited by the implicit base type.
8085 Set_Discriminant_Constraint
8086 (New_Base, Discriminant_Constraint (Derived_Type));
8092 -- If we get here Derived_Type will have no discriminants or it will be
8093 -- a discriminated unconstrained base type.
8095 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8099 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8100 -- The declaration of a specific descendant of an interface type
8101 -- freezes the interface type (RM 13.14).
8103 if not Private_Extension or else Is_Interface (Parent_Base) then
8104 Freeze_Before (N, Parent_Type);
8107 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8108 -- cannot be declared at a deeper level than its parent type is
8109 -- removed. The check on derivation within a generic body is also
8110 -- relaxed, but there's a restriction that a derived tagged type
8111 -- cannot be declared in a generic body if it's derived directly
8112 -- or indirectly from a formal type of that generic.
8114 if Ada_Version >= Ada_2005 then
8115 if Present (Enclosing_Generic_Body (Derived_Type)) then
8117 Ancestor_Type : Entity_Id;
8120 -- Check to see if any ancestor of the derived type is a
8123 Ancestor_Type := Parent_Type;
8124 while not Is_Generic_Type (Ancestor_Type)
8125 and then Etype (Ancestor_Type) /= Ancestor_Type
8127 Ancestor_Type := Etype (Ancestor_Type);
8130 -- If the derived type does have a formal type as an
8131 -- ancestor, then it's an error if the derived type is
8132 -- declared within the body of the generic unit that
8133 -- declares the formal type in its generic formal part. It's
8134 -- sufficient to check whether the ancestor type is declared
8135 -- inside the same generic body as the derived type (such as
8136 -- within a nested generic spec), in which case the
8137 -- derivation is legal. If the formal type is declared
8138 -- outside of that generic body, then it's guaranteed that
8139 -- the derived type is declared within the generic body of
8140 -- the generic unit declaring the formal type.
8142 if Is_Generic_Type (Ancestor_Type)
8143 and then Enclosing_Generic_Body (Ancestor_Type) /=
8144 Enclosing_Generic_Body (Derived_Type)
8147 ("parent type of& must not be descendant of formal type"
8148 & " of an enclosing generic body",
8149 Indic, Derived_Type);
8154 elsif Type_Access_Level (Derived_Type) /=
8155 Type_Access_Level (Parent_Type)
8156 and then not Is_Generic_Type (Derived_Type)
8158 if Is_Controlled (Parent_Type) then
8160 ("controlled type must be declared at the library level",
8164 ("type extension at deeper accessibility level than parent",
8170 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8173 and then GB /= Enclosing_Generic_Body (Parent_Base)
8176 ("parent type of& must not be outside generic body"
8178 Indic, Derived_Type);
8184 -- Ada 2005 (AI-251)
8186 if Ada_Version >= Ada_2005 and then Is_Tagged then
8188 -- "The declaration of a specific descendant of an interface type
8189 -- freezes the interface type" (RM 13.14).
8194 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8195 Iface := First (Interface_List (Type_Def));
8196 while Present (Iface) loop
8197 Freeze_Before (N, Etype (Iface));
8204 -- STEP 1b : preliminary cleanup of the full view of private types
8206 -- If the type is already marked as having discriminants, then it's the
8207 -- completion of a private type or private extension and we need to
8208 -- retain the discriminants from the partial view if the current
8209 -- declaration has Discriminant_Specifications so that we can verify
8210 -- conformance. However, we must remove any existing components that
8211 -- were inherited from the parent (and attached in Copy_And_Swap)
8212 -- because the full type inherits all appropriate components anyway, and
8213 -- we do not want the partial view's components interfering.
8215 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8216 Discrim := First_Discriminant (Derived_Type);
8218 Last_Discrim := Discrim;
8219 Next_Discriminant (Discrim);
8220 exit when No (Discrim);
8223 Set_Last_Entity (Derived_Type, Last_Discrim);
8225 -- In all other cases wipe out the list of inherited components (even
8226 -- inherited discriminants), it will be properly rebuilt here.
8229 Set_First_Entity (Derived_Type, Empty);
8230 Set_Last_Entity (Derived_Type, Empty);
8233 -- STEP 1c: Initialize some flags for the Derived_Type
8235 -- The following flags must be initialized here so that
8236 -- Process_Discriminants can check that discriminants of tagged types do
8237 -- not have a default initial value and that access discriminants are
8238 -- only specified for limited records. For completeness, these flags are
8239 -- also initialized along with all the other flags below.
8241 -- AI-419: Limitedness is not inherited from an interface parent, so to
8242 -- be limited in that case the type must be explicitly declared as
8243 -- limited. However, task and protected interfaces are always limited.
8245 if Limited_Present (Type_Def) then
8246 Set_Is_Limited_Record (Derived_Type);
8248 elsif Is_Limited_Record (Parent_Type)
8249 or else (Present (Full_View (Parent_Type))
8250 and then Is_Limited_Record (Full_View (Parent_Type)))
8252 if not Is_Interface (Parent_Type)
8253 or else Is_Synchronized_Interface (Parent_Type)
8254 or else Is_Protected_Interface (Parent_Type)
8255 or else Is_Task_Interface (Parent_Type)
8257 Set_Is_Limited_Record (Derived_Type);
8261 -- STEP 2a: process discriminants of derived type if any
8263 Push_Scope (Derived_Type);
8265 if Discriminant_Specs then
8266 Set_Has_Unknown_Discriminants (Derived_Type, False);
8268 -- The following call initializes fields Has_Discriminants and
8269 -- Discriminant_Constraint, unless we are processing the completion
8270 -- of a private type declaration.
8272 Check_Or_Process_Discriminants (N, Derived_Type);
8274 -- For untagged types, the constraint on the Parent_Type must be
8275 -- present and is used to rename the discriminants.
8277 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8278 Error_Msg_N ("untagged parent must have discriminants", Indic);
8280 elsif not Is_Tagged and then not Constraint_Present then
8282 ("discriminant constraint needed for derived untagged records",
8285 -- Otherwise the parent subtype must be constrained unless we have a
8286 -- private extension.
8288 elsif not Constraint_Present
8289 and then not Private_Extension
8290 and then not Is_Constrained (Parent_Type)
8293 ("unconstrained type not allowed in this context", Indic);
8295 elsif Constraint_Present then
8296 -- The following call sets the field Corresponding_Discriminant
8297 -- for the discriminants in the Derived_Type.
8299 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8301 -- For untagged types all new discriminants must rename
8302 -- discriminants in the parent. For private extensions new
8303 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8305 Discrim := First_Discriminant (Derived_Type);
8306 while Present (Discrim) loop
8308 and then No (Corresponding_Discriminant (Discrim))
8311 ("new discriminants must constrain old ones", Discrim);
8313 elsif Private_Extension
8314 and then Present (Corresponding_Discriminant (Discrim))
8317 ("only static constraints allowed for parent"
8318 & " discriminants in the partial view", Indic);
8322 -- If a new discriminant is used in the constraint, then its
8323 -- subtype must be statically compatible with the parent
8324 -- discriminant's subtype (3.7(15)).
8326 -- However, if the record contains an array constrained by
8327 -- the discriminant but with some different bound, the compiler
8328 -- attemps to create a smaller range for the discriminant type.
8329 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8330 -- the discriminant type is a scalar type, the check must use
8331 -- the original discriminant type in the parent declaration.
8334 Corr_Disc : constant Entity_Id :=
8335 Corresponding_Discriminant (Discrim);
8336 Disc_Type : constant Entity_Id := Etype (Discrim);
8337 Corr_Type : Entity_Id;
8340 if Present (Corr_Disc) then
8341 if Is_Scalar_Type (Disc_Type) then
8343 Entity (Discriminant_Type (Parent (Corr_Disc)));
8345 Corr_Type := Etype (Corr_Disc);
8349 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8352 ("subtype must be compatible "
8353 & "with parent discriminant",
8359 Next_Discriminant (Discrim);
8362 -- Check whether the constraints of the full view statically
8363 -- match those imposed by the parent subtype [7.3(13)].
8365 if Present (Stored_Constraint (Derived_Type)) then
8370 C1 := First_Elmt (Discs);
8371 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8372 while Present (C1) and then Present (C2) loop
8374 Fully_Conformant_Expressions (Node (C1), Node (C2))
8377 ("not conformant with previous declaration",
8388 -- STEP 2b: No new discriminants, inherit discriminants if any
8391 if Private_Extension then
8392 Set_Has_Unknown_Discriminants
8394 Has_Unknown_Discriminants (Parent_Type)
8395 or else Unknown_Discriminants_Present (N));
8397 -- The partial view of the parent may have unknown discriminants,
8398 -- but if the full view has discriminants and the parent type is
8399 -- in scope they must be inherited.
8401 elsif Has_Unknown_Discriminants (Parent_Type)
8403 (not Has_Discriminants (Parent_Type)
8404 or else not In_Open_Scopes (Scope (Parent_Type)))
8406 Set_Has_Unknown_Discriminants (Derived_Type);
8409 if not Has_Unknown_Discriminants (Derived_Type)
8410 and then not Has_Unknown_Discriminants (Parent_Base)
8411 and then Has_Discriminants (Parent_Type)
8413 Inherit_Discrims := True;
8414 Set_Has_Discriminants
8415 (Derived_Type, True);
8416 Set_Discriminant_Constraint
8417 (Derived_Type, Discriminant_Constraint (Parent_Base));
8420 -- The following test is true for private types (remember
8421 -- transformation 5. is not applied to those) and in an error
8424 if Constraint_Present then
8425 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8428 -- For now mark a new derived type as constrained only if it has no
8429 -- discriminants. At the end of Build_Derived_Record_Type we properly
8430 -- set this flag in the case of private extensions. See comments in
8431 -- point 9. just before body of Build_Derived_Record_Type.
8435 not (Inherit_Discrims
8436 or else Has_Unknown_Discriminants (Derived_Type)));
8439 -- STEP 3: initialize fields of derived type
8441 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8442 Set_Stored_Constraint (Derived_Type, No_Elist);
8444 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8445 -- but cannot be interfaces
8447 if not Private_Extension
8448 and then Ekind (Derived_Type) /= E_Private_Type
8449 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8451 if Interface_Present (Type_Def) then
8452 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8455 Set_Interfaces (Derived_Type, No_Elist);
8458 -- Fields inherited from the Parent_Type
8460 Set_Has_Specified_Layout
8461 (Derived_Type, Has_Specified_Layout (Parent_Type));
8462 Set_Is_Limited_Composite
8463 (Derived_Type, Is_Limited_Composite (Parent_Type));
8464 Set_Is_Private_Composite
8465 (Derived_Type, Is_Private_Composite (Parent_Type));
8467 if Is_Tagged_Type (Parent_Type) then
8468 Set_No_Tagged_Streams_Pragma
8469 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8472 -- Fields inherited from the Parent_Base
8474 Set_Has_Controlled_Component
8475 (Derived_Type, Has_Controlled_Component (Parent_Base));
8476 Set_Has_Non_Standard_Rep
8477 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8478 Set_Has_Primitive_Operations
8479 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8481 -- Fields inherited from the Parent_Base in the non-private case
8483 if Ekind (Derived_Type) = E_Record_Type then
8484 Set_Has_Complex_Representation
8485 (Derived_Type, Has_Complex_Representation (Parent_Base));
8488 -- Fields inherited from the Parent_Base for record types
8490 if Is_Record_Type (Derived_Type) then
8492 Parent_Full : Entity_Id;
8495 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8496 -- Parent_Base can be a private type or private extension. Go
8497 -- to the full view here to get the E_Record_Type specific flags.
8499 if Present (Full_View (Parent_Base)) then
8500 Parent_Full := Full_View (Parent_Base);
8502 Parent_Full := Parent_Base;
8505 Set_OK_To_Reorder_Components
8506 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8510 -- Set fields for private derived types
8512 if Is_Private_Type (Derived_Type) then
8513 Set_Depends_On_Private (Derived_Type, True);
8514 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8516 -- Inherit fields from non private record types. If this is the
8517 -- completion of a derivation from a private type, the parent itself
8518 -- is private, and the attributes come from its full view, which must
8522 if Is_Private_Type (Parent_Base)
8523 and then not Is_Record_Type (Parent_Base)
8525 Set_Component_Alignment
8526 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8528 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8530 Set_Component_Alignment
8531 (Derived_Type, Component_Alignment (Parent_Base));
8533 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8537 -- Set fields for tagged types
8540 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8542 -- All tagged types defined in Ada.Finalization are controlled
8544 if Chars (Scope (Derived_Type)) = Name_Finalization
8545 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8546 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8548 Set_Is_Controlled (Derived_Type);
8550 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8553 -- Minor optimization: there is no need to generate the class-wide
8554 -- entity associated with an underlying record view.
8556 if not Is_Underlying_Record_View (Derived_Type) then
8557 Make_Class_Wide_Type (Derived_Type);
8560 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8562 if Has_Discriminants (Derived_Type)
8563 and then Constraint_Present
8565 Set_Stored_Constraint
8566 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8569 if Ada_Version >= Ada_2005 then
8571 Ifaces_List : Elist_Id;
8574 -- Checks rules 3.9.4 (13/2 and 14/2)
8576 if Comes_From_Source (Derived_Type)
8577 and then not Is_Private_Type (Derived_Type)
8578 and then Is_Interface (Parent_Type)
8579 and then not Is_Interface (Derived_Type)
8581 if Is_Task_Interface (Parent_Type) then
8583 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8586 elsif Is_Protected_Interface (Parent_Type) then
8588 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8593 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8595 Check_Interfaces (N, Type_Def);
8597 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8598 -- not already in the parents.
8602 Ifaces_List => Ifaces_List,
8603 Exclude_Parents => True);
8605 Set_Interfaces (Derived_Type, Ifaces_List);
8607 -- If the derived type is the anonymous type created for
8608 -- a declaration whose parent has a constraint, propagate
8609 -- the interface list to the source type. This must be done
8610 -- prior to the completion of the analysis of the source type
8611 -- because the components in the extension may contain current
8612 -- instances whose legality depends on some ancestor.
8614 if Is_Itype (Derived_Type) then
8616 Def : constant Node_Id :=
8617 Associated_Node_For_Itype (Derived_Type);
8620 and then Nkind (Def) = N_Full_Type_Declaration
8623 (Defining_Identifier (Def), Ifaces_List);
8628 -- A type extension is automatically Ghost when one of its
8629 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8630 -- also inherited when the parent type is Ghost, but this is
8631 -- done in Build_Derived_Type as the mechanism also handles
8632 -- untagged derivations.
8634 if Implements_Ghost_Interface (Derived_Type) then
8635 Set_Is_Ghost_Entity (Derived_Type);
8641 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8642 Set_Has_Non_Standard_Rep
8643 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8646 -- STEP 4: Inherit components from the parent base and constrain them.
8647 -- Apply the second transformation described in point 6. above.
8649 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8650 or else not Has_Discriminants (Parent_Type)
8651 or else not Is_Constrained (Parent_Type)
8655 Constrs := Discriminant_Constraint (Parent_Type);
8660 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8662 -- STEP 5a: Copy the parent record declaration for untagged types
8664 if not Is_Tagged then
8666 -- Discriminant_Constraint (Derived_Type) has been properly
8667 -- constructed. Save it and temporarily set it to Empty because we
8668 -- do not want the call to New_Copy_Tree below to mess this list.
8670 if Has_Discriminants (Derived_Type) then
8671 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8672 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8674 Save_Discr_Constr := No_Elist;
8677 -- Save the Etype field of Derived_Type. It is correctly set now,
8678 -- but the call to New_Copy tree may remap it to point to itself,
8679 -- which is not what we want. Ditto for the Next_Entity field.
8681 Save_Etype := Etype (Derived_Type);
8682 Save_Next_Entity := Next_Entity (Derived_Type);
8684 -- Assoc_List maps all stored discriminants in the Parent_Base to
8685 -- stored discriminants in the Derived_Type. It is fundamental that
8686 -- no types or itypes with discriminants other than the stored
8687 -- discriminants appear in the entities declared inside
8688 -- Derived_Type, since the back end cannot deal with it.
8692 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8694 -- Restore the fields saved prior to the New_Copy_Tree call
8695 -- and compute the stored constraint.
8697 Set_Etype (Derived_Type, Save_Etype);
8698 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8700 if Has_Discriminants (Derived_Type) then
8701 Set_Discriminant_Constraint
8702 (Derived_Type, Save_Discr_Constr);
8703 Set_Stored_Constraint
8704 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8705 Replace_Components (Derived_Type, New_Decl);
8706 Set_Has_Implicit_Dereference
8707 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8710 -- Insert the new derived type declaration
8712 Rewrite (N, New_Decl);
8714 -- STEP 5b: Complete the processing for record extensions in generics
8716 -- There is no completion for record extensions declared in the
8717 -- parameter part of a generic, so we need to complete processing for
8718 -- these generic record extensions here. The Record_Type_Definition call
8719 -- will change the Ekind of the components from E_Void to E_Component.
8721 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8722 Record_Type_Definition (Empty, Derived_Type);
8724 -- STEP 5c: Process the record extension for non private tagged types
8726 elsif not Private_Extension then
8727 Expand_Record_Extension (Derived_Type, Type_Def);
8729 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8730 -- derived type to propagate some semantic information. This led
8731 -- to other ASIS failures and has been removed.
8733 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8734 -- implemented interfaces if we are in expansion mode
8737 and then Has_Interfaces (Derived_Type)
8739 Add_Interface_Tag_Components (N, Derived_Type);
8742 -- Analyze the record extension
8744 Record_Type_Definition
8745 (Record_Extension_Part (Type_Def), Derived_Type);
8750 -- Nothing else to do if there is an error in the derivation.
8751 -- An unusual case: the full view may be derived from a type in an
8752 -- instance, when the partial view was used illegally as an actual
8753 -- in that instance, leading to a circular definition.
8755 if Etype (Derived_Type) = Any_Type
8756 or else Etype (Parent_Type) = Derived_Type
8761 -- Set delayed freeze and then derive subprograms, we need to do
8762 -- this in this order so that derived subprograms inherit the
8763 -- derived freeze if necessary.
8765 Set_Has_Delayed_Freeze (Derived_Type);
8767 if Derive_Subps then
8768 Derive_Subprograms (Parent_Type, Derived_Type);
8771 -- If we have a private extension which defines a constrained derived
8772 -- type mark as constrained here after we have derived subprograms. See
8773 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8775 if Private_Extension and then Inherit_Discrims then
8776 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8777 Set_Is_Constrained (Derived_Type, True);
8778 Set_Discriminant_Constraint (Derived_Type, Discs);
8780 elsif Is_Constrained (Parent_Type) then
8782 (Derived_Type, True);
8783 Set_Discriminant_Constraint
8784 (Derived_Type, Discriminant_Constraint (Parent_Type));
8788 -- Update the class-wide type, which shares the now-completed entity
8789 -- list with its specific type. In case of underlying record views,
8790 -- we do not generate the corresponding class wide entity.
8793 and then not Is_Underlying_Record_View (Derived_Type)
8796 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8798 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8801 Check_Function_Writable_Actuals (N);
8802 end Build_Derived_Record_Type;
8804 ------------------------
8805 -- Build_Derived_Type --
8806 ------------------------
8808 procedure Build_Derived_Type
8810 Parent_Type : Entity_Id;
8811 Derived_Type : Entity_Id;
8812 Is_Completion : Boolean;
8813 Derive_Subps : Boolean := True)
8815 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8818 -- Set common attributes
8820 Set_Scope (Derived_Type, Current_Scope);
8822 Set_Etype (Derived_Type, Parent_Base);
8823 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8824 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8825 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8827 Set_Size_Info (Derived_Type, Parent_Type);
8828 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8829 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8830 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8831 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8833 if Is_Tagged_Type (Derived_Type) then
8834 Set_No_Tagged_Streams_Pragma
8835 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8838 -- If the parent has primitive routines, set the derived type link
8840 if Has_Primitive_Operations (Parent_Type) then
8841 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8844 -- If the parent type is a private subtype, the convention on the base
8845 -- type may be set in the private part, and not propagated to the
8846 -- subtype until later, so we obtain the convention from the base type.
8848 Set_Convention (Derived_Type, Convention (Parent_Base));
8850 -- Set SSO default for record or array type
8852 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8853 and then Is_Base_Type (Derived_Type)
8855 Set_Default_SSO (Derived_Type);
8858 -- Propagate invariant information. The new type has invariants if
8859 -- they are inherited from the parent type, and these invariants can
8860 -- be further inherited, so both flags are set.
8862 -- We similarly inherit predicates
8864 if Has_Predicates (Parent_Type) then
8865 Set_Has_Predicates (Derived_Type);
8868 -- The derived type inherits the representation clauses of the parent
8870 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8872 -- Propagate the attributes related to pragma Default_Initial_Condition
8873 -- from the parent type to the private extension. A derived type always
8874 -- inherits the default initial condition flag from the parent type. If
8875 -- the derived type carries its own Default_Initial_Condition pragma,
8876 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8877 -- mutually exclusive.
8879 Propagate_Default_Init_Cond_Attributes
8880 (From_Typ => Parent_Type,
8881 To_Typ => Derived_Type,
8882 Parent_To_Derivation => True);
8884 -- If the parent type has delayed rep aspects, then mark the derived
8885 -- type as possibly inheriting a delayed rep aspect.
8887 if Has_Delayed_Rep_Aspects (Parent_Type) then
8888 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8891 -- Propagate the attributes related to pragma Ghost from the parent type
8892 -- to the derived type or type extension (SPARK RM 6.9(9)).
8894 if Is_Ghost_Entity (Parent_Type) then
8895 Set_Is_Ghost_Entity (Derived_Type);
8898 -- Type dependent processing
8900 case Ekind (Parent_Type) is
8901 when Numeric_Kind =>
8902 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8905 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8909 | Class_Wide_Kind =>
8910 Build_Derived_Record_Type
8911 (N, Parent_Type, Derived_Type, Derive_Subps);
8914 when Enumeration_Kind =>
8915 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8918 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8920 when Incomplete_Or_Private_Kind =>
8921 Build_Derived_Private_Type
8922 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8924 -- For discriminated types, the derivation includes deriving
8925 -- primitive operations. For others it is done below.
8927 if Is_Tagged_Type (Parent_Type)
8928 or else Has_Discriminants (Parent_Type)
8929 or else (Present (Full_View (Parent_Type))
8930 and then Has_Discriminants (Full_View (Parent_Type)))
8935 when Concurrent_Kind =>
8936 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8939 raise Program_Error;
8942 -- Nothing more to do if some error occurred
8944 if Etype (Derived_Type) = Any_Type then
8948 -- Set delayed freeze and then derive subprograms, we need to do this
8949 -- in this order so that derived subprograms inherit the derived freeze
8952 Set_Has_Delayed_Freeze (Derived_Type);
8954 if Derive_Subps then
8955 Derive_Subprograms (Parent_Type, Derived_Type);
8958 Set_Has_Primitive_Operations
8959 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8960 end Build_Derived_Type;
8962 -----------------------
8963 -- Build_Discriminal --
8964 -----------------------
8966 procedure Build_Discriminal (Discrim : Entity_Id) is
8967 D_Minal : Entity_Id;
8968 CR_Disc : Entity_Id;
8971 -- A discriminal has the same name as the discriminant
8973 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8975 Set_Ekind (D_Minal, E_In_Parameter);
8976 Set_Mechanism (D_Minal, Default_Mechanism);
8977 Set_Etype (D_Minal, Etype (Discrim));
8978 Set_Scope (D_Minal, Current_Scope);
8980 Set_Discriminal (Discrim, D_Minal);
8981 Set_Discriminal_Link (D_Minal, Discrim);
8983 -- For task types, build at once the discriminants of the corresponding
8984 -- record, which are needed if discriminants are used in entry defaults
8985 -- and in family bounds.
8987 if Is_Concurrent_Type (Current_Scope)
8989 Is_Limited_Type (Current_Scope)
8991 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8993 Set_Ekind (CR_Disc, E_In_Parameter);
8994 Set_Mechanism (CR_Disc, Default_Mechanism);
8995 Set_Etype (CR_Disc, Etype (Discrim));
8996 Set_Scope (CR_Disc, Current_Scope);
8997 Set_Discriminal_Link (CR_Disc, Discrim);
8998 Set_CR_Discriminant (Discrim, CR_Disc);
9000 end Build_Discriminal;
9002 ------------------------------------
9003 -- Build_Discriminant_Constraints --
9004 ------------------------------------
9006 function Build_Discriminant_Constraints
9009 Derived_Def : Boolean := False) return Elist_Id
9011 C : constant Node_Id := Constraint (Def);
9012 Nb_Discr : constant Nat := Number_Discriminants (T);
9014 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9015 -- Saves the expression corresponding to a given discriminant in T
9017 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9018 -- Return the Position number within array Discr_Expr of a discriminant
9019 -- D within the discriminant list of the discriminated type T.
9021 procedure Process_Discriminant_Expression
9024 -- If this is a discriminant constraint on a partial view, do not
9025 -- generate an overflow check on the discriminant expression. The check
9026 -- will be generated when constraining the full view. Otherwise the
9027 -- backend creates duplicate symbols for the temporaries corresponding
9028 -- to the expressions to be checked, causing spurious assembler errors.
9034 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9038 Disc := First_Discriminant (T);
9039 for J in Discr_Expr'Range loop
9044 Next_Discriminant (Disc);
9047 -- Note: Since this function is called on discriminants that are
9048 -- known to belong to the discriminated type, falling through the
9049 -- loop with no match signals an internal compiler error.
9051 raise Program_Error;
9054 -------------------------------------
9055 -- Process_Discriminant_Expression --
9056 -------------------------------------
9058 procedure Process_Discriminant_Expression
9062 BDT : constant Entity_Id := Base_Type (Etype (D));
9065 -- If this is a discriminant constraint on a partial view, do
9066 -- not generate an overflow on the discriminant expression. The
9067 -- check will be generated when constraining the full view.
9069 if Is_Private_Type (T)
9070 and then Present (Full_View (T))
9072 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9074 Analyze_And_Resolve (Expr, BDT);
9076 end Process_Discriminant_Expression;
9078 -- Declarations local to Build_Discriminant_Constraints
9082 Elist : constant Elist_Id := New_Elmt_List;
9090 Discrim_Present : Boolean := False;
9092 -- Start of processing for Build_Discriminant_Constraints
9095 -- The following loop will process positional associations only.
9096 -- For a positional association, the (single) discriminant is
9097 -- implicitly specified by position, in textual order (RM 3.7.2).
9099 Discr := First_Discriminant (T);
9100 Constr := First (Constraints (C));
9101 for D in Discr_Expr'Range loop
9102 exit when Nkind (Constr) = N_Discriminant_Association;
9105 Error_Msg_N ("too few discriminants given in constraint", C);
9106 return New_Elmt_List;
9108 elsif Nkind (Constr) = N_Range
9109 or else (Nkind (Constr) = N_Attribute_Reference
9110 and then Attribute_Name (Constr) = Name_Range)
9113 ("a range is not a valid discriminant constraint", Constr);
9114 Discr_Expr (D) := Error;
9117 Process_Discriminant_Expression (Constr, Discr);
9118 Discr_Expr (D) := Constr;
9121 Next_Discriminant (Discr);
9125 if No (Discr) and then Present (Constr) then
9126 Error_Msg_N ("too many discriminants given in constraint", Constr);
9127 return New_Elmt_List;
9130 -- Named associations can be given in any order, but if both positional
9131 -- and named associations are used in the same discriminant constraint,
9132 -- then positional associations must occur first, at their normal
9133 -- position. Hence once a named association is used, the rest of the
9134 -- discriminant constraint must use only named associations.
9136 while Present (Constr) loop
9138 -- Positional association forbidden after a named association
9140 if Nkind (Constr) /= N_Discriminant_Association then
9141 Error_Msg_N ("positional association follows named one", Constr);
9142 return New_Elmt_List;
9144 -- Otherwise it is a named association
9147 -- E records the type of the discriminants in the named
9148 -- association. All the discriminants specified in the same name
9149 -- association must have the same type.
9153 -- Search the list of discriminants in T to see if the simple name
9154 -- given in the constraint matches any of them.
9156 Id := First (Selector_Names (Constr));
9157 while Present (Id) loop
9160 -- If Original_Discriminant is present, we are processing a
9161 -- generic instantiation and this is an instance node. We need
9162 -- to find the name of the corresponding discriminant in the
9163 -- actual record type T and not the name of the discriminant in
9164 -- the generic formal. Example:
9167 -- type G (D : int) is private;
9169 -- subtype W is G (D => 1);
9171 -- type Rec (X : int) is record ... end record;
9172 -- package Q is new P (G => Rec);
9174 -- At the point of the instantiation, formal type G is Rec
9175 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9176 -- which really looks like "subtype W is Rec (D => 1);" at
9177 -- the point of instantiation, we want to find the discriminant
9178 -- that corresponds to D in Rec, i.e. X.
9180 if Present (Original_Discriminant (Id))
9181 and then In_Instance
9183 Discr := Find_Corresponding_Discriminant (Id, T);
9187 Discr := First_Discriminant (T);
9188 while Present (Discr) loop
9189 if Chars (Discr) = Chars (Id) then
9194 Next_Discriminant (Discr);
9198 Error_Msg_N ("& does not match any discriminant", Id);
9199 return New_Elmt_List;
9201 -- If the parent type is a generic formal, preserve the
9202 -- name of the discriminant for subsequent instances.
9203 -- see comment at the beginning of this if statement.
9205 elsif Is_Generic_Type (Root_Type (T)) then
9206 Set_Original_Discriminant (Id, Discr);
9210 Position := Pos_Of_Discr (T, Discr);
9212 if Present (Discr_Expr (Position)) then
9213 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9216 -- Each discriminant specified in the same named association
9217 -- must be associated with a separate copy of the
9218 -- corresponding expression.
9220 if Present (Next (Id)) then
9221 Expr := New_Copy_Tree (Expression (Constr));
9222 Set_Parent (Expr, Parent (Expression (Constr)));
9224 Expr := Expression (Constr);
9227 Discr_Expr (Position) := Expr;
9228 Process_Discriminant_Expression (Expr, Discr);
9231 -- A discriminant association with more than one discriminant
9232 -- name is only allowed if the named discriminants are all of
9233 -- the same type (RM 3.7.1(8)).
9236 E := Base_Type (Etype (Discr));
9238 elsif Base_Type (Etype (Discr)) /= E then
9240 ("all discriminants in an association " &
9241 "must have the same type", Id);
9251 -- A discriminant constraint must provide exactly one value for each
9252 -- discriminant of the type (RM 3.7.1(8)).
9254 for J in Discr_Expr'Range loop
9255 if No (Discr_Expr (J)) then
9256 Error_Msg_N ("too few discriminants given in constraint", C);
9257 return New_Elmt_List;
9261 -- Determine if there are discriminant expressions in the constraint
9263 for J in Discr_Expr'Range loop
9264 if Denotes_Discriminant
9265 (Discr_Expr (J), Check_Concurrent => True)
9267 Discrim_Present := True;
9271 -- Build an element list consisting of the expressions given in the
9272 -- discriminant constraint and apply the appropriate checks. The list
9273 -- is constructed after resolving any named discriminant associations
9274 -- and therefore the expressions appear in the textual order of the
9277 Discr := First_Discriminant (T);
9278 for J in Discr_Expr'Range loop
9279 if Discr_Expr (J) /= Error then
9280 Append_Elmt (Discr_Expr (J), Elist);
9282 -- If any of the discriminant constraints is given by a
9283 -- discriminant and we are in a derived type declaration we
9284 -- have a discriminant renaming. Establish link between new
9285 -- and old discriminant.
9287 if Denotes_Discriminant (Discr_Expr (J)) then
9289 Set_Corresponding_Discriminant
9290 (Entity (Discr_Expr (J)), Discr);
9293 -- Force the evaluation of non-discriminant expressions.
9294 -- If we have found a discriminant in the constraint 3.4(26)
9295 -- and 3.8(18) demand that no range checks are performed are
9296 -- after evaluation. If the constraint is for a component
9297 -- definition that has a per-object constraint, expressions are
9298 -- evaluated but not checked either. In all other cases perform
9302 if Discrim_Present then
9305 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9307 Has_Per_Object_Constraint
9308 (Defining_Identifier (Parent (Parent (Def))))
9312 elsif Is_Access_Type (Etype (Discr)) then
9313 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9316 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9319 Force_Evaluation (Discr_Expr (J));
9322 -- Check that the designated type of an access discriminant's
9323 -- expression is not a class-wide type unless the discriminant's
9324 -- designated type is also class-wide.
9326 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9327 and then not Is_Class_Wide_Type
9328 (Designated_Type (Etype (Discr)))
9329 and then Etype (Discr_Expr (J)) /= Any_Type
9330 and then Is_Class_Wide_Type
9331 (Designated_Type (Etype (Discr_Expr (J))))
9333 Wrong_Type (Discr_Expr (J), Etype (Discr));
9335 elsif Is_Access_Type (Etype (Discr))
9336 and then not Is_Access_Constant (Etype (Discr))
9337 and then Is_Access_Type (Etype (Discr_Expr (J)))
9338 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9341 ("constraint for discriminant& must be access to variable",
9346 Next_Discriminant (Discr);
9350 end Build_Discriminant_Constraints;
9352 ---------------------------------
9353 -- Build_Discriminated_Subtype --
9354 ---------------------------------
9356 procedure Build_Discriminated_Subtype
9360 Related_Nod : Node_Id;
9361 For_Access : Boolean := False)
9363 Has_Discrs : constant Boolean := Has_Discriminants (T);
9364 Constrained : constant Boolean :=
9366 and then not Is_Empty_Elmt_List (Elist)
9367 and then not Is_Class_Wide_Type (T))
9368 or else Is_Constrained (T);
9371 if Ekind (T) = E_Record_Type then
9373 Set_Ekind (Def_Id, E_Private_Subtype);
9374 Set_Is_For_Access_Subtype (Def_Id, True);
9376 Set_Ekind (Def_Id, E_Record_Subtype);
9379 -- Inherit preelaboration flag from base, for types for which it
9380 -- may have been set: records, private types, protected types.
9382 Set_Known_To_Have_Preelab_Init
9383 (Def_Id, Known_To_Have_Preelab_Init (T));
9385 elsif Ekind (T) = E_Task_Type then
9386 Set_Ekind (Def_Id, E_Task_Subtype);
9388 elsif Ekind (T) = E_Protected_Type then
9389 Set_Ekind (Def_Id, E_Protected_Subtype);
9390 Set_Known_To_Have_Preelab_Init
9391 (Def_Id, Known_To_Have_Preelab_Init (T));
9393 elsif Is_Private_Type (T) then
9394 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9395 Set_Known_To_Have_Preelab_Init
9396 (Def_Id, Known_To_Have_Preelab_Init (T));
9398 -- Private subtypes may have private dependents
9400 Set_Private_Dependents (Def_Id, New_Elmt_List);
9402 elsif Is_Class_Wide_Type (T) then
9403 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9406 -- Incomplete type. Attach subtype to list of dependents, to be
9407 -- completed with full view of parent type, unless is it the
9408 -- designated subtype of a record component within an init_proc.
9409 -- This last case arises for a component of an access type whose
9410 -- designated type is incomplete (e.g. a Taft Amendment type).
9411 -- The designated subtype is within an inner scope, and needs no
9412 -- elaboration, because only the access type is needed in the
9413 -- initialization procedure.
9415 Set_Ekind (Def_Id, Ekind (T));
9417 if For_Access and then Within_Init_Proc then
9420 Append_Elmt (Def_Id, Private_Dependents (T));
9424 Set_Etype (Def_Id, T);
9425 Init_Size_Align (Def_Id);
9426 Set_Has_Discriminants (Def_Id, Has_Discrs);
9427 Set_Is_Constrained (Def_Id, Constrained);
9429 Set_First_Entity (Def_Id, First_Entity (T));
9430 Set_Last_Entity (Def_Id, Last_Entity (T));
9431 Set_Has_Implicit_Dereference
9432 (Def_Id, Has_Implicit_Dereference (T));
9434 -- If the subtype is the completion of a private declaration, there may
9435 -- have been representation clauses for the partial view, and they must
9436 -- be preserved. Build_Derived_Type chains the inherited clauses with
9437 -- the ones appearing on the extension. If this comes from a subtype
9438 -- declaration, all clauses are inherited.
9440 if No (First_Rep_Item (Def_Id)) then
9441 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9444 if Is_Tagged_Type (T) then
9445 Set_Is_Tagged_Type (Def_Id);
9446 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9447 Make_Class_Wide_Type (Def_Id);
9450 Set_Stored_Constraint (Def_Id, No_Elist);
9453 Set_Discriminant_Constraint (Def_Id, Elist);
9454 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9457 if Is_Tagged_Type (T) then
9459 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9460 -- concurrent record type (which has the list of primitive
9463 if Ada_Version >= Ada_2005
9464 and then Is_Concurrent_Type (T)
9466 Set_Corresponding_Record_Type (Def_Id,
9467 Corresponding_Record_Type (T));
9469 Set_Direct_Primitive_Operations (Def_Id,
9470 Direct_Primitive_Operations (T));
9473 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9476 -- Subtypes introduced by component declarations do not need to be
9477 -- marked as delayed, and do not get freeze nodes, because the semantics
9478 -- verifies that the parents of the subtypes are frozen before the
9479 -- enclosing record is frozen.
9481 if not Is_Type (Scope (Def_Id)) then
9482 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9484 if Is_Private_Type (T)
9485 and then Present (Full_View (T))
9487 Conditional_Delay (Def_Id, Full_View (T));
9489 Conditional_Delay (Def_Id, T);
9493 if Is_Record_Type (T) then
9494 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9497 and then not Is_Empty_Elmt_List (Elist)
9498 and then not For_Access
9500 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9501 elsif not For_Access then
9502 Set_Cloned_Subtype (Def_Id, T);
9505 end Build_Discriminated_Subtype;
9507 ---------------------------
9508 -- Build_Itype_Reference --
9509 ---------------------------
9511 procedure Build_Itype_Reference
9515 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9518 -- Itype references are only created for use by the back-end
9520 if Inside_A_Generic then
9523 Set_Itype (IR, Ityp);
9524 Insert_After (Nod, IR);
9526 end Build_Itype_Reference;
9528 ------------------------
9529 -- Build_Scalar_Bound --
9530 ------------------------
9532 function Build_Scalar_Bound
9535 Der_T : Entity_Id) return Node_Id
9537 New_Bound : Entity_Id;
9540 -- Note: not clear why this is needed, how can the original bound
9541 -- be unanalyzed at this point? and if it is, what business do we
9542 -- have messing around with it? and why is the base type of the
9543 -- parent type the right type for the resolution. It probably is
9544 -- not. It is OK for the new bound we are creating, but not for
9545 -- the old one??? Still if it never happens, no problem.
9547 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9549 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9550 New_Bound := New_Copy (Bound);
9551 Set_Etype (New_Bound, Der_T);
9552 Set_Analyzed (New_Bound);
9554 elsif Is_Entity_Name (Bound) then
9555 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9557 -- The following is almost certainly wrong. What business do we have
9558 -- relocating a node (Bound) that is presumably still attached to
9559 -- the tree elsewhere???
9562 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9565 Set_Etype (New_Bound, Der_T);
9567 end Build_Scalar_Bound;
9569 --------------------------------
9570 -- Build_Underlying_Full_View --
9571 --------------------------------
9573 procedure Build_Underlying_Full_View
9578 Loc : constant Source_Ptr := Sloc (N);
9579 Subt : constant Entity_Id :=
9580 Make_Defining_Identifier
9581 (Loc, New_External_Name (Chars (Typ), 'S'));
9588 procedure Set_Discriminant_Name (Id : Node_Id);
9589 -- If the derived type has discriminants, they may rename discriminants
9590 -- of the parent. When building the full view of the parent, we need to
9591 -- recover the names of the original discriminants if the constraint is
9592 -- given by named associations.
9594 ---------------------------
9595 -- Set_Discriminant_Name --
9596 ---------------------------
9598 procedure Set_Discriminant_Name (Id : Node_Id) is
9602 Set_Original_Discriminant (Id, Empty);
9604 if Has_Discriminants (Typ) then
9605 Disc := First_Discriminant (Typ);
9606 while Present (Disc) loop
9607 if Chars (Disc) = Chars (Id)
9608 and then Present (Corresponding_Discriminant (Disc))
9610 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9612 Next_Discriminant (Disc);
9615 end Set_Discriminant_Name;
9617 -- Start of processing for Build_Underlying_Full_View
9620 if Nkind (N) = N_Full_Type_Declaration then
9621 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9623 elsif Nkind (N) = N_Subtype_Declaration then
9624 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9626 elsif Nkind (N) = N_Component_Declaration then
9629 (Constraint (Subtype_Indication (Component_Definition (N))));
9632 raise Program_Error;
9635 C := First (Constraints (Constr));
9636 while Present (C) loop
9637 if Nkind (C) = N_Discriminant_Association then
9638 Id := First (Selector_Names (C));
9639 while Present (Id) loop
9640 Set_Discriminant_Name (Id);
9649 Make_Subtype_Declaration (Loc,
9650 Defining_Identifier => Subt,
9651 Subtype_Indication =>
9652 Make_Subtype_Indication (Loc,
9653 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9654 Constraint => New_Copy_Tree (Constr)));
9656 -- If this is a component subtype for an outer itype, it is not
9657 -- a list member, so simply set the parent link for analysis: if
9658 -- the enclosing type does not need to be in a declarative list,
9659 -- neither do the components.
9661 if Is_List_Member (N)
9662 and then Nkind (N) /= N_Component_Declaration
9664 Insert_Before (N, Indic);
9666 Set_Parent (Indic, Parent (N));
9670 Set_Underlying_Full_View (Typ, Full_View (Subt));
9671 end Build_Underlying_Full_View;
9673 -------------------------------
9674 -- Check_Abstract_Overriding --
9675 -------------------------------
9677 procedure Check_Abstract_Overriding (T : Entity_Id) is
9678 Alias_Subp : Entity_Id;
9684 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9685 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9686 -- which has pragma Implemented already set. Check whether Subp's entity
9687 -- kind conforms to the implementation kind of the overridden routine.
9689 procedure Check_Pragma_Implemented
9691 Iface_Subp : Entity_Id);
9692 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9693 -- Iface_Subp and both entities have pragma Implemented already set on
9694 -- them. Check whether the two implementation kinds are conforming.
9696 procedure Inherit_Pragma_Implemented
9698 Iface_Subp : Entity_Id);
9699 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9700 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9701 -- Propagate the implementation kind of Iface_Subp to Subp.
9703 ------------------------------
9704 -- Check_Pragma_Implemented --
9705 ------------------------------
9707 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9708 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9709 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9710 Subp_Alias : constant Entity_Id := Alias (Subp);
9711 Contr_Typ : Entity_Id;
9712 Impl_Subp : Entity_Id;
9715 -- Subp must have an alias since it is a hidden entity used to link
9716 -- an interface subprogram to its overriding counterpart.
9718 pragma Assert (Present (Subp_Alias));
9720 -- Handle aliases to synchronized wrappers
9722 Impl_Subp := Subp_Alias;
9724 if Is_Primitive_Wrapper (Impl_Subp) then
9725 Impl_Subp := Wrapped_Entity (Impl_Subp);
9728 -- Extract the type of the controlling formal
9730 Contr_Typ := Etype (First_Formal (Subp_Alias));
9732 if Is_Concurrent_Record_Type (Contr_Typ) then
9733 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9736 -- An interface subprogram whose implementation kind is By_Entry must
9737 -- be implemented by an entry.
9739 if Impl_Kind = Name_By_Entry
9740 and then Ekind (Impl_Subp) /= E_Entry
9742 Error_Msg_Node_2 := Iface_Alias;
9744 ("type & must implement abstract subprogram & with an entry",
9745 Subp_Alias, Contr_Typ);
9747 elsif Impl_Kind = Name_By_Protected_Procedure then
9749 -- An interface subprogram whose implementation kind is By_
9750 -- Protected_Procedure cannot be implemented by a primitive
9751 -- procedure of a task type.
9753 if Ekind (Contr_Typ) /= E_Protected_Type then
9754 Error_Msg_Node_2 := Contr_Typ;
9756 ("interface subprogram & cannot be implemented by a " &
9757 "primitive procedure of task type &", Subp_Alias,
9760 -- An interface subprogram whose implementation kind is By_
9761 -- Protected_Procedure must be implemented by a procedure.
9763 elsif Ekind (Impl_Subp) /= E_Procedure then
9764 Error_Msg_Node_2 := Iface_Alias;
9766 ("type & must implement abstract subprogram & with a " &
9767 "procedure", Subp_Alias, Contr_Typ);
9769 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9770 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9772 Error_Msg_Name_1 := Impl_Kind;
9774 ("overriding operation& must have synchronization%",
9778 -- If primitive has Optional synchronization, overriding operation
9779 -- must match if it has an explicit synchronization..
9781 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9782 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9784 Error_Msg_Name_1 := Impl_Kind;
9786 ("overriding operation& must have syncrhonization%",
9789 end Check_Pragma_Implemented;
9791 ------------------------------
9792 -- Check_Pragma_Implemented --
9793 ------------------------------
9795 procedure Check_Pragma_Implemented
9797 Iface_Subp : Entity_Id)
9799 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9800 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9803 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9804 -- and overriding subprogram are different. In general this is an
9805 -- error except when the implementation kind of the overridden
9806 -- subprograms is By_Any or Optional.
9808 if Iface_Kind /= Subp_Kind
9809 and then Iface_Kind /= Name_By_Any
9810 and then Iface_Kind /= Name_Optional
9812 if Iface_Kind = Name_By_Entry then
9814 ("incompatible implementation kind, overridden subprogram " &
9815 "is marked By_Entry", Subp);
9818 ("incompatible implementation kind, overridden subprogram " &
9819 "is marked By_Protected_Procedure", Subp);
9822 end Check_Pragma_Implemented;
9824 --------------------------------
9825 -- Inherit_Pragma_Implemented --
9826 --------------------------------
9828 procedure Inherit_Pragma_Implemented
9830 Iface_Subp : Entity_Id)
9832 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9833 Loc : constant Source_Ptr := Sloc (Subp);
9834 Impl_Prag : Node_Id;
9837 -- Since the implementation kind is stored as a representation item
9838 -- rather than a flag, create a pragma node.
9842 Chars => Name_Implemented,
9843 Pragma_Argument_Associations => New_List (
9844 Make_Pragma_Argument_Association (Loc,
9845 Expression => New_Occurrence_Of (Subp, Loc)),
9847 Make_Pragma_Argument_Association (Loc,
9848 Expression => Make_Identifier (Loc, Iface_Kind))));
9850 -- The pragma doesn't need to be analyzed because it is internally
9851 -- built. It is safe to directly register it as a rep item since we
9852 -- are only interested in the characters of the implementation kind.
9854 Record_Rep_Item (Subp, Impl_Prag);
9855 end Inherit_Pragma_Implemented;
9857 -- Start of processing for Check_Abstract_Overriding
9860 Op_List := Primitive_Operations (T);
9862 -- Loop to check primitive operations
9864 Elmt := First_Elmt (Op_List);
9865 while Present (Elmt) loop
9866 Subp := Node (Elmt);
9867 Alias_Subp := Alias (Subp);
9869 -- Inherited subprograms are identified by the fact that they do not
9870 -- come from source, and the associated source location is the
9871 -- location of the first subtype of the derived type.
9873 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9874 -- subprograms that "require overriding".
9876 -- Special exception, do not complain about failure to override the
9877 -- stream routines _Input and _Output, as well as the primitive
9878 -- operations used in dispatching selects since we always provide
9879 -- automatic overridings for these subprograms.
9881 -- Also ignore this rule for convention CIL since .NET libraries
9882 -- do bizarre things with interfaces???
9884 -- The partial view of T may have been a private extension, for
9885 -- which inherited functions dispatching on result are abstract.
9886 -- If the full view is a null extension, there is no need for
9887 -- overriding in Ada 2005, but wrappers need to be built for them
9888 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9890 if Is_Null_Extension (T)
9891 and then Has_Controlling_Result (Subp)
9892 and then Ada_Version >= Ada_2005
9893 and then Present (Alias_Subp)
9894 and then not Comes_From_Source (Subp)
9895 and then not Is_Abstract_Subprogram (Alias_Subp)
9896 and then not Is_Access_Type (Etype (Subp))
9900 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9901 -- processing because this check is done with the aliased
9904 elsif Present (Interface_Alias (Subp)) then
9907 elsif (Is_Abstract_Subprogram (Subp)
9908 or else Requires_Overriding (Subp)
9910 (Has_Controlling_Result (Subp)
9911 and then Present (Alias_Subp)
9912 and then not Comes_From_Source (Subp)
9913 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9914 and then not Is_TSS (Subp, TSS_Stream_Input)
9915 and then not Is_TSS (Subp, TSS_Stream_Output)
9916 and then not Is_Abstract_Type (T)
9917 and then Convention (T) /= Convention_CIL
9918 and then not Is_Predefined_Interface_Primitive (Subp)
9920 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9921 -- with abstract interface types because the check will be done
9922 -- with the aliased entity (otherwise we generate a duplicated
9925 and then not Present (Interface_Alias (Subp))
9927 if Present (Alias_Subp) then
9929 -- Only perform the check for a derived subprogram when the
9930 -- type has an explicit record extension. This avoids incorrect
9931 -- flagging of abstract subprograms for the case of a type
9932 -- without an extension that is derived from a formal type
9933 -- with a tagged actual (can occur within a private part).
9935 -- Ada 2005 (AI-391): In the case of an inherited function with
9936 -- a controlling result of the type, the rule does not apply if
9937 -- the type is a null extension (unless the parent function
9938 -- itself is abstract, in which case the function must still be
9939 -- be overridden). The expander will generate an overriding
9940 -- wrapper function calling the parent subprogram (see
9941 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9943 Type_Def := Type_Definition (Parent (T));
9945 if Nkind (Type_Def) = N_Derived_Type_Definition
9946 and then Present (Record_Extension_Part (Type_Def))
9948 (Ada_Version < Ada_2005
9949 or else not Is_Null_Extension (T)
9950 or else Ekind (Subp) = E_Procedure
9951 or else not Has_Controlling_Result (Subp)
9952 or else Is_Abstract_Subprogram (Alias_Subp)
9953 or else Requires_Overriding (Subp)
9954 or else Is_Access_Type (Etype (Subp)))
9956 -- Avoid reporting error in case of abstract predefined
9957 -- primitive inherited from interface type because the
9958 -- body of internally generated predefined primitives
9959 -- of tagged types are generated later by Freeze_Type
9961 if Is_Interface (Root_Type (T))
9962 and then Is_Abstract_Subprogram (Subp)
9963 and then Is_Predefined_Dispatching_Operation (Subp)
9964 and then not Comes_From_Source (Ultimate_Alias (Subp))
9968 -- A null extension is not obliged to override an inherited
9969 -- procedure subject to pragma Extensions_Visible with value
9970 -- False and at least one controlling OUT parameter
9971 -- (SPARK RM 6.1.7(6)).
9973 elsif Is_Null_Extension (T)
9974 and then Is_EVF_Procedure (Subp)
9980 ("type must be declared abstract or & overridden",
9983 -- Traverse the whole chain of aliased subprograms to
9984 -- complete the error notification. This is especially
9985 -- useful for traceability of the chain of entities when
9986 -- the subprogram corresponds with an interface
9987 -- subprogram (which may be defined in another package).
9989 if Present (Alias_Subp) then
9995 while Present (Alias (E)) loop
9997 -- Avoid reporting redundant errors on entities
9998 -- inherited from interfaces
10000 if Sloc (E) /= Sloc (T) then
10001 Error_Msg_Sloc := Sloc (E);
10003 ("\& has been inherited #", T, Subp);
10009 Error_Msg_Sloc := Sloc (E);
10011 -- AI05-0068: report if there is an overriding
10012 -- non-abstract subprogram that is invisible.
10015 and then not Is_Abstract_Subprogram (E)
10018 ("\& subprogram# is not visible",
10021 -- Clarify the case where a non-null extension must
10022 -- override inherited procedure subject to pragma
10023 -- Extensions_Visible with value False and at least
10024 -- one controlling OUT param.
10026 elsif Is_EVF_Procedure (E) then
10028 ("\& # is subject to Extensions_Visible False",
10033 ("\& has been inherited from subprogram #",
10040 -- Ada 2005 (AI-345): Protected or task type implementing
10041 -- abstract interfaces.
10043 elsif Is_Concurrent_Record_Type (T)
10044 and then Present (Interfaces (T))
10046 -- If an inherited subprogram is implemented by a protected
10047 -- procedure or an entry, then the first parameter of the
10048 -- inherited subprogram shall be of mode OUT or IN OUT, or
10049 -- an access-to-variable parameter (RM 9.4(11.9/3))
10051 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
10052 and then Ekind (First_Formal (Subp)) = E_In_Parameter
10053 and then Ekind (Subp) /= E_Function
10054 and then not Is_Predefined_Dispatching_Operation (Subp)
10056 Error_Msg_PT (T, Subp);
10058 -- Some other kind of overriding failure
10062 ("interface subprogram & must be overridden",
10065 -- Examine primitive operations of synchronized type,
10066 -- to find homonyms that have the wrong profile.
10073 First_Entity (Corresponding_Concurrent_Type (T));
10074 while Present (Prim) loop
10075 if Chars (Prim) = Chars (Subp) then
10077 ("profile is not type conformant with "
10078 & "prefixed view profile of "
10079 & "inherited operation&", Prim, Subp);
10082 Next_Entity (Prim);
10089 Error_Msg_Node_2 := T;
10091 ("abstract subprogram& not allowed for type&", Subp);
10093 -- Also post unconditional warning on the type (unconditional
10094 -- so that if there are more than one of these cases, we get
10095 -- them all, and not just the first one).
10097 Error_Msg_Node_2 := Subp;
10098 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10101 -- A subprogram subject to pragma Extensions_Visible with value
10102 -- "True" cannot override a subprogram subject to the same pragma
10103 -- with value "False" (SPARK RM 6.1.7(5)).
10105 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10106 and then Present (Overridden_Operation (Subp))
10107 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10108 Extensions_Visible_False
10110 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10112 ("subprogram & with Extensions_Visible True cannot override "
10113 & "subprogram # with Extensions_Visible False", Subp);
10116 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10118 -- Subp is an expander-generated procedure which maps an interface
10119 -- alias to a protected wrapper. The interface alias is flagged by
10120 -- pragma Implemented. Ensure that Subp is a procedure when the
10121 -- implementation kind is By_Protected_Procedure or an entry when
10124 if Ada_Version >= Ada_2012
10125 and then Is_Hidden (Subp)
10126 and then Present (Interface_Alias (Subp))
10127 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10129 Check_Pragma_Implemented (Subp);
10132 -- Subp is an interface primitive which overrides another interface
10133 -- primitive marked with pragma Implemented.
10135 if Ada_Version >= Ada_2012
10136 and then Present (Overridden_Operation (Subp))
10137 and then Has_Rep_Pragma
10138 (Overridden_Operation (Subp), Name_Implemented)
10140 -- If the overriding routine is also marked by Implemented, check
10141 -- that the two implementation kinds are conforming.
10143 if Has_Rep_Pragma (Subp, Name_Implemented) then
10144 Check_Pragma_Implemented
10146 Iface_Subp => Overridden_Operation (Subp));
10148 -- Otherwise the overriding routine inherits the implementation
10149 -- kind from the overridden subprogram.
10152 Inherit_Pragma_Implemented
10154 Iface_Subp => Overridden_Operation (Subp));
10158 -- If the operation is a wrapper for a synchronized primitive, it
10159 -- may be called indirectly through a dispatching select. We assume
10160 -- that it will be referenced elsewhere indirectly, and suppress
10161 -- warnings about an unused entity.
10163 if Is_Primitive_Wrapper (Subp)
10164 and then Present (Wrapped_Entity (Subp))
10166 Set_Referenced (Wrapped_Entity (Subp));
10171 end Check_Abstract_Overriding;
10173 ------------------------------------------------
10174 -- Check_Access_Discriminant_Requires_Limited --
10175 ------------------------------------------------
10177 procedure Check_Access_Discriminant_Requires_Limited
10182 -- A discriminant_specification for an access discriminant shall appear
10183 -- only in the declaration for a task or protected type, or for a type
10184 -- with the reserved word 'limited' in its definition or in one of its
10185 -- ancestors (RM 3.7(10)).
10187 -- AI-0063: The proper condition is that type must be immutably limited,
10188 -- or else be a partial view.
10190 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10191 if Is_Limited_View (Current_Scope)
10193 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10194 and then Limited_Present (Parent (Current_Scope)))
10200 ("access discriminants allowed only for limited types", Loc);
10203 end Check_Access_Discriminant_Requires_Limited;
10205 -----------------------------------
10206 -- Check_Aliased_Component_Types --
10207 -----------------------------------
10209 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10213 -- ??? Also need to check components of record extensions, but not
10214 -- components of protected types (which are always limited).
10216 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10217 -- types to be unconstrained. This is safe because it is illegal to
10218 -- create access subtypes to such types with explicit discriminant
10221 if not Is_Limited_Type (T) then
10222 if Ekind (T) = E_Record_Type then
10223 C := First_Component (T);
10224 while Present (C) loop
10226 and then Has_Discriminants (Etype (C))
10227 and then not Is_Constrained (Etype (C))
10228 and then not In_Instance_Body
10229 and then Ada_Version < Ada_2005
10232 ("aliased component must be constrained (RM 3.6(11))",
10236 Next_Component (C);
10239 elsif Ekind (T) = E_Array_Type then
10240 if Has_Aliased_Components (T)
10241 and then Has_Discriminants (Component_Type (T))
10242 and then not Is_Constrained (Component_Type (T))
10243 and then not In_Instance_Body
10244 and then Ada_Version < Ada_2005
10247 ("aliased component type must be constrained (RM 3.6(11))",
10252 end Check_Aliased_Component_Types;
10254 ---------------------------------------
10255 -- Check_Anonymous_Access_Components --
10256 ---------------------------------------
10258 procedure Check_Anonymous_Access_Components
10259 (Typ_Decl : Node_Id;
10262 Comp_List : Node_Id)
10264 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10265 Anon_Access : Entity_Id;
10268 Comp_Def : Node_Id;
10270 Type_Def : Node_Id;
10272 procedure Build_Incomplete_Type_Declaration;
10273 -- If the record type contains components that include an access to the
10274 -- current record, then create an incomplete type declaration for the
10275 -- record, to be used as the designated type of the anonymous access.
10276 -- This is done only once, and only if there is no previous partial
10277 -- view of the type.
10279 function Designates_T (Subt : Node_Id) return Boolean;
10280 -- Check whether a node designates the enclosing record type, or 'Class
10283 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10284 -- Check whether an access definition includes a reference to
10285 -- the enclosing record type. The reference can be a subtype mark
10286 -- in the access definition itself, a 'Class attribute reference, or
10287 -- recursively a reference appearing in a parameter specification
10288 -- or result definition of an access_to_subprogram definition.
10290 --------------------------------------
10291 -- Build_Incomplete_Type_Declaration --
10292 --------------------------------------
10294 procedure Build_Incomplete_Type_Declaration is
10299 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10300 -- it's "is new ... with record" or else "is tagged record ...".
10302 Is_Tagged : constant Boolean :=
10303 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10305 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10307 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10308 and then Tagged_Present (Type_Definition (Typ_Decl)));
10311 -- If there is a previous partial view, no need to create a new one
10312 -- If the partial view, given by Prev, is incomplete, If Prev is
10313 -- a private declaration, full declaration is flagged accordingly.
10315 if Prev /= Typ then
10317 Make_Class_Wide_Type (Prev);
10318 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10319 Set_Etype (Class_Wide_Type (Typ), Typ);
10324 elsif Has_Private_Declaration (Typ) then
10326 -- If we refer to T'Class inside T, and T is the completion of a
10327 -- private type, then make sure the class-wide type exists.
10330 Make_Class_Wide_Type (Typ);
10335 -- If there was a previous anonymous access type, the incomplete
10336 -- type declaration will have been created already.
10338 elsif Present (Current_Entity (Typ))
10339 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10340 and then Full_View (Current_Entity (Typ)) = Typ
10343 and then Comes_From_Source (Current_Entity (Typ))
10344 and then not Is_Tagged_Type (Current_Entity (Typ))
10346 Make_Class_Wide_Type (Typ);
10348 ("incomplete view of tagged type should be declared tagged??",
10349 Parent (Current_Entity (Typ)));
10354 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10355 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10357 -- Type has already been inserted into the current scope. Remove
10358 -- it, and add incomplete declaration for type, so that subsequent
10359 -- anonymous access types can use it. The entity is unchained from
10360 -- the homonym list and from immediate visibility. After analysis,
10361 -- the entity in the incomplete declaration becomes immediately
10362 -- visible in the record declaration that follows.
10364 H := Current_Entity (Typ);
10367 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10370 and then Homonym (H) /= Typ
10372 H := Homonym (Typ);
10375 Set_Homonym (H, Homonym (Typ));
10378 Insert_Before (Typ_Decl, Decl);
10380 Set_Full_View (Inc_T, Typ);
10384 -- Create a common class-wide type for both views, and set the
10385 -- Etype of the class-wide type to the full view.
10387 Make_Class_Wide_Type (Inc_T);
10388 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10389 Set_Etype (Class_Wide_Type (Typ), Typ);
10392 end Build_Incomplete_Type_Declaration;
10398 function Designates_T (Subt : Node_Id) return Boolean is
10399 Type_Id : constant Name_Id := Chars (Typ);
10401 function Names_T (Nam : Node_Id) return Boolean;
10402 -- The record type has not been introduced in the current scope
10403 -- yet, so we must examine the name of the type itself, either
10404 -- an identifier T, or an expanded name of the form P.T, where
10405 -- P denotes the current scope.
10411 function Names_T (Nam : Node_Id) return Boolean is
10413 if Nkind (Nam) = N_Identifier then
10414 return Chars (Nam) = Type_Id;
10416 elsif Nkind (Nam) = N_Selected_Component then
10417 if Chars (Selector_Name (Nam)) = Type_Id then
10418 if Nkind (Prefix (Nam)) = N_Identifier then
10419 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10421 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10422 return Chars (Selector_Name (Prefix (Nam))) =
10423 Chars (Current_Scope);
10437 -- Start of processing for Designates_T
10440 if Nkind (Subt) = N_Identifier then
10441 return Chars (Subt) = Type_Id;
10443 -- Reference can be through an expanded name which has not been
10444 -- analyzed yet, and which designates enclosing scopes.
10446 elsif Nkind (Subt) = N_Selected_Component then
10447 if Names_T (Subt) then
10450 -- Otherwise it must denote an entity that is already visible.
10451 -- The access definition may name a subtype of the enclosing
10452 -- type, if there is a previous incomplete declaration for it.
10455 Find_Selected_Component (Subt);
10457 Is_Entity_Name (Subt)
10458 and then Scope (Entity (Subt)) = Current_Scope
10460 (Chars (Base_Type (Entity (Subt))) = Type_Id
10462 (Is_Class_Wide_Type (Entity (Subt))
10464 Chars (Etype (Base_Type (Entity (Subt)))) =
10468 -- A reference to the current type may appear as the prefix of
10469 -- a 'Class attribute.
10471 elsif Nkind (Subt) = N_Attribute_Reference
10472 and then Attribute_Name (Subt) = Name_Class
10474 return Names_T (Prefix (Subt));
10485 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10486 Param_Spec : Node_Id;
10488 Acc_Subprg : constant Node_Id :=
10489 Access_To_Subprogram_Definition (Acc_Def);
10492 if No (Acc_Subprg) then
10493 return Designates_T (Subtype_Mark (Acc_Def));
10496 -- Component is an access_to_subprogram: examine its formals,
10497 -- and result definition in the case of an access_to_function.
10499 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10500 while Present (Param_Spec) loop
10501 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10502 and then Mentions_T (Parameter_Type (Param_Spec))
10506 elsif Designates_T (Parameter_Type (Param_Spec)) then
10513 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10514 if Nkind (Result_Definition (Acc_Subprg)) =
10515 N_Access_Definition
10517 return Mentions_T (Result_Definition (Acc_Subprg));
10519 return Designates_T (Result_Definition (Acc_Subprg));
10526 -- Start of processing for Check_Anonymous_Access_Components
10529 if No (Comp_List) then
10533 Comp := First (Component_Items (Comp_List));
10534 while Present (Comp) loop
10535 if Nkind (Comp) = N_Component_Declaration
10537 (Access_Definition (Component_Definition (Comp)))
10539 Mentions_T (Access_Definition (Component_Definition (Comp)))
10541 Comp_Def := Component_Definition (Comp);
10543 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10545 Build_Incomplete_Type_Declaration;
10546 Anon_Access := Make_Temporary (Loc, 'S');
10548 -- Create a declaration for the anonymous access type: either
10549 -- an access_to_object or an access_to_subprogram.
10551 if Present (Acc_Def) then
10552 if Nkind (Acc_Def) = N_Access_Function_Definition then
10554 Make_Access_Function_Definition (Loc,
10555 Parameter_Specifications =>
10556 Parameter_Specifications (Acc_Def),
10557 Result_Definition => Result_Definition (Acc_Def));
10560 Make_Access_Procedure_Definition (Loc,
10561 Parameter_Specifications =>
10562 Parameter_Specifications (Acc_Def));
10567 Make_Access_To_Object_Definition (Loc,
10568 Subtype_Indication =>
10570 (Subtype_Mark (Access_Definition (Comp_Def))));
10572 Set_Constant_Present
10573 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10575 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10578 Set_Null_Exclusion_Present
10580 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10583 Make_Full_Type_Declaration (Loc,
10584 Defining_Identifier => Anon_Access,
10585 Type_Definition => Type_Def);
10587 Insert_Before (Typ_Decl, Decl);
10590 -- If an access to subprogram, create the extra formals
10592 if Present (Acc_Def) then
10593 Create_Extra_Formals (Designated_Type (Anon_Access));
10595 -- If an access to object, preserve entity of designated type,
10596 -- for ASIS use, before rewriting the component definition.
10603 Desig := Entity (Subtype_Indication (Type_Def));
10605 -- If the access definition is to the current record,
10606 -- the visible entity at this point is an incomplete
10607 -- type. Retrieve the full view to simplify ASIS queries
10609 if Ekind (Desig) = E_Incomplete_Type then
10610 Desig := Full_View (Desig);
10614 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10619 Make_Component_Definition (Loc,
10620 Subtype_Indication =>
10621 New_Occurrence_Of (Anon_Access, Loc)));
10623 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10624 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10626 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10629 Set_Is_Local_Anonymous_Access (Anon_Access);
10635 if Present (Variant_Part (Comp_List)) then
10639 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10640 while Present (V) loop
10641 Check_Anonymous_Access_Components
10642 (Typ_Decl, Typ, Prev, Component_List (V));
10643 Next_Non_Pragma (V);
10647 end Check_Anonymous_Access_Components;
10649 ----------------------
10650 -- Check_Completion --
10651 ----------------------
10653 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10656 procedure Post_Error;
10657 -- Post error message for lack of completion for entity E
10663 procedure Post_Error is
10665 procedure Missing_Body;
10666 -- Output missing body message
10672 procedure Missing_Body is
10674 -- Spec is in same unit, so we can post on spec
10676 if In_Same_Source_Unit (Body_Id, E) then
10677 Error_Msg_N ("missing body for &", E);
10679 -- Spec is in a separate unit, so we have to post on the body
10682 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10686 -- Start of processing for Post_Error
10689 if not Comes_From_Source (E) then
10691 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10693 -- It may be an anonymous protected type created for a
10694 -- single variable. Post error on variable, if present.
10700 Var := First_Entity (Current_Scope);
10701 while Present (Var) loop
10702 exit when Etype (Var) = E
10703 and then Comes_From_Source (Var);
10708 if Present (Var) then
10715 -- If a generated entity has no completion, then either previous
10716 -- semantic errors have disabled the expansion phase, or else we had
10717 -- missing subunits, or else we are compiling without expansion,
10718 -- or else something is very wrong.
10720 if not Comes_From_Source (E) then
10722 (Serious_Errors_Detected > 0
10723 or else Configurable_Run_Time_Violations > 0
10724 or else Subunits_Missing
10725 or else not Expander_Active);
10728 -- Here for source entity
10731 -- Here if no body to post the error message, so we post the error
10732 -- on the declaration that has no completion. This is not really
10733 -- the right place to post it, think about this later ???
10735 if No (Body_Id) then
10736 if Is_Type (E) then
10738 ("missing full declaration for }", Parent (E), E);
10740 Error_Msg_NE ("missing body for &", Parent (E), E);
10743 -- Package body has no completion for a declaration that appears
10744 -- in the corresponding spec. Post error on the body, with a
10745 -- reference to the non-completed declaration.
10748 Error_Msg_Sloc := Sloc (E);
10750 if Is_Type (E) then
10751 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10753 elsif Is_Overloadable (E)
10754 and then Current_Entity_In_Scope (E) /= E
10756 -- It may be that the completion is mistyped and appears as
10757 -- a distinct overloading of the entity.
10760 Candidate : constant Entity_Id :=
10761 Current_Entity_In_Scope (E);
10762 Decl : constant Node_Id :=
10763 Unit_Declaration_Node (Candidate);
10766 if Is_Overloadable (Candidate)
10767 and then Ekind (Candidate) = Ekind (E)
10768 and then Nkind (Decl) = N_Subprogram_Body
10769 and then Acts_As_Spec (Decl)
10771 Check_Type_Conformant (Candidate, E);
10787 Pack_Id : constant Entity_Id := Current_Scope;
10789 -- Start of processing for Check_Completion
10792 E := First_Entity (Pack_Id);
10793 while Present (E) loop
10794 if Is_Intrinsic_Subprogram (E) then
10797 -- A Ghost entity declared in a non-Ghost package does not force the
10798 -- need for a body (SPARK RM 6.9(11)).
10800 elsif not Is_Ghost_Entity (Pack_Id) and then Is_Ghost_Entity (E) then
10803 -- The following situation requires special handling: a child unit
10804 -- that appears in the context clause of the body of its parent:
10806 -- procedure Parent.Child (...);
10808 -- with Parent.Child;
10809 -- package body Parent is
10811 -- Here Parent.Child appears as a local entity, but should not be
10812 -- flagged as requiring completion, because it is a compilation
10815 -- Ignore missing completion for a subprogram that does not come from
10816 -- source (including the _Call primitive operation of RAS types,
10817 -- which has to have the flag Comes_From_Source for other purposes):
10818 -- we assume that the expander will provide the missing completion.
10819 -- In case of previous errors, other expansion actions that provide
10820 -- bodies for null procedures with not be invoked, so inhibit message
10823 -- Note that E_Operator is not in the list that follows, because
10824 -- this kind is reserved for predefined operators, that are
10825 -- intrinsic and do not need completion.
10827 elsif Ekind_In (E, E_Function,
10829 E_Generic_Function,
10830 E_Generic_Procedure)
10832 if Has_Completion (E) then
10835 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10838 elsif Is_Subprogram (E)
10839 and then (not Comes_From_Source (E)
10840 or else Chars (E) = Name_uCall)
10845 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10849 elsif Nkind (Parent (E)) = N_Procedure_Specification
10850 and then Null_Present (Parent (E))
10851 and then Serious_Errors_Detected > 0
10859 elsif Is_Entry (E) then
10860 if not Has_Completion (E) and then
10861 (Ekind (Scope (E)) = E_Protected_Object
10862 or else Ekind (Scope (E)) = E_Protected_Type)
10867 elsif Is_Package_Or_Generic_Package (E) then
10868 if Unit_Requires_Body (E) then
10869 if not Has_Completion (E)
10870 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10876 elsif not Is_Child_Unit (E) then
10877 May_Need_Implicit_Body (E);
10880 -- A formal incomplete type (Ada 2012) does not require a completion;
10881 -- other incomplete type declarations do.
10883 elsif Ekind (E) = E_Incomplete_Type
10884 and then No (Underlying_Type (E))
10885 and then not Is_Generic_Type (E)
10889 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10890 and then not Has_Completion (E)
10894 -- A single task declared in the current scope is a constant, verify
10895 -- that the body of its anonymous type is in the same scope. If the
10896 -- task is defined elsewhere, this may be a renaming declaration for
10897 -- which no completion is needed.
10899 elsif Ekind (E) = E_Constant
10900 and then Ekind (Etype (E)) = E_Task_Type
10901 and then not Has_Completion (Etype (E))
10902 and then Scope (Etype (E)) = Current_Scope
10906 elsif Ekind (E) = E_Protected_Object
10907 and then not Has_Completion (Etype (E))
10911 elsif Ekind (E) = E_Record_Type then
10912 if Is_Tagged_Type (E) then
10913 Check_Abstract_Overriding (E);
10914 Check_Conventions (E);
10917 Check_Aliased_Component_Types (E);
10919 elsif Ekind (E) = E_Array_Type then
10920 Check_Aliased_Component_Types (E);
10926 end Check_Completion;
10928 ------------------------------------
10929 -- Check_CPP_Type_Has_No_Defaults --
10930 ------------------------------------
10932 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10933 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10938 -- Obtain the component list
10940 if Nkind (Tdef) = N_Record_Definition then
10941 Clist := Component_List (Tdef);
10942 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10943 Clist := Component_List (Record_Extension_Part (Tdef));
10946 -- Check all components to ensure no default expressions
10948 if Present (Clist) then
10949 Comp := First (Component_Items (Clist));
10950 while Present (Comp) loop
10951 if Present (Expression (Comp)) then
10953 ("component of imported 'C'P'P type cannot have "
10954 & "default expression", Expression (Comp));
10960 end Check_CPP_Type_Has_No_Defaults;
10962 ----------------------------
10963 -- Check_Delta_Expression --
10964 ----------------------------
10966 procedure Check_Delta_Expression (E : Node_Id) is
10968 if not (Is_Real_Type (Etype (E))) then
10969 Wrong_Type (E, Any_Real);
10971 elsif not Is_OK_Static_Expression (E) then
10972 Flag_Non_Static_Expr
10973 ("non-static expression used for delta value!", E);
10975 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10976 Error_Msg_N ("delta expression must be positive", E);
10982 -- If any of above errors occurred, then replace the incorrect
10983 -- expression by the real 0.1, which should prevent further errors.
10986 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10987 Analyze_And_Resolve (E, Standard_Float);
10988 end Check_Delta_Expression;
10990 -----------------------------
10991 -- Check_Digits_Expression --
10992 -----------------------------
10994 procedure Check_Digits_Expression (E : Node_Id) is
10996 if not (Is_Integer_Type (Etype (E))) then
10997 Wrong_Type (E, Any_Integer);
10999 elsif not Is_OK_Static_Expression (E) then
11000 Flag_Non_Static_Expr
11001 ("non-static expression used for digits value!", E);
11003 elsif Expr_Value (E) <= 0 then
11004 Error_Msg_N ("digits value must be greater than zero", E);
11010 -- If any of above errors occurred, then replace the incorrect
11011 -- expression by the integer 1, which should prevent further errors.
11013 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11014 Analyze_And_Resolve (E, Standard_Integer);
11016 end Check_Digits_Expression;
11018 --------------------------
11019 -- Check_Initialization --
11020 --------------------------
11022 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11024 -- Special processing for limited types
11026 if Is_Limited_Type (T)
11027 and then not In_Instance
11028 and then not In_Inlined_Body
11030 if not OK_For_Limited_Init (T, Exp) then
11032 -- In GNAT mode, this is just a warning, to allow it to be evilly
11033 -- turned off. Otherwise it is a real error.
11037 ("??cannot initialize entities of limited type!", Exp);
11039 elsif Ada_Version < Ada_2005 then
11041 -- The side effect removal machinery may generate illegal Ada
11042 -- code to avoid the usage of access types and 'reference in
11043 -- SPARK mode. Since this is legal code with respect to theorem
11044 -- proving, do not emit the error.
11047 and then Nkind (Exp) = N_Function_Call
11048 and then Nkind (Parent (Exp)) = N_Object_Declaration
11049 and then not Comes_From_Source
11050 (Defining_Identifier (Parent (Exp)))
11056 ("cannot initialize entities of limited type", Exp);
11057 Explain_Limited_Type (T, Exp);
11061 -- Specialize error message according to kind of illegal
11062 -- initial expression.
11064 if Nkind (Exp) = N_Type_Conversion
11065 and then Nkind (Expression (Exp)) = N_Function_Call
11068 ("illegal context for call"
11069 & " to function with limited result", Exp);
11073 ("initialization of limited object requires aggregate "
11074 & "or function call", Exp);
11080 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11081 -- set unless we can be sure that no range check is required.
11083 if (GNATprove_Mode or not Expander_Active)
11084 and then Is_Scalar_Type (T)
11085 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11087 Set_Do_Range_Check (Exp);
11089 end Check_Initialization;
11091 ----------------------
11092 -- Check_Interfaces --
11093 ----------------------
11095 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11096 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11099 Iface_Def : Node_Id;
11100 Iface_Typ : Entity_Id;
11101 Parent_Node : Node_Id;
11103 Is_Task : Boolean := False;
11104 -- Set True if parent type or any progenitor is a task interface
11106 Is_Protected : Boolean := False;
11107 -- Set True if parent type or any progenitor is a protected interface
11109 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11110 -- Check that a progenitor is compatible with declaration. If an error
11111 -- message is output, it is posted on Error_Node.
11117 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11118 Iface_Id : constant Entity_Id :=
11119 Defining_Identifier (Parent (Iface_Def));
11120 Type_Def : Node_Id;
11123 if Nkind (N) = N_Private_Extension_Declaration then
11126 Type_Def := Type_Definition (N);
11129 if Is_Task_Interface (Iface_Id) then
11132 elsif Is_Protected_Interface (Iface_Id) then
11133 Is_Protected := True;
11136 if Is_Synchronized_Interface (Iface_Id) then
11138 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11139 -- extension derived from a synchronized interface must explicitly
11140 -- be declared synchronized, because the full view will be a
11141 -- synchronized type.
11143 if Nkind (N) = N_Private_Extension_Declaration then
11144 if not Synchronized_Present (N) then
11146 ("private extension of& must be explicitly synchronized",
11150 -- However, by 3.9.4(16/2), a full type that is a record extension
11151 -- is never allowed to derive from a synchronized interface (note
11152 -- that interfaces must be excluded from this check, because those
11153 -- are represented by derived type definitions in some cases).
11155 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11156 and then not Interface_Present (Type_Definition (N))
11158 Error_Msg_N ("record extension cannot derive from synchronized "
11159 & "interface", Error_Node);
11163 -- Check that the characteristics of the progenitor are compatible
11164 -- with the explicit qualifier in the declaration.
11165 -- The check only applies to qualifiers that come from source.
11166 -- Limited_Present also appears in the declaration of corresponding
11167 -- records, and the check does not apply to them.
11169 if Limited_Present (Type_Def)
11171 Is_Concurrent_Record_Type (Defining_Identifier (N))
11173 if Is_Limited_Interface (Parent_Type)
11174 and then not Is_Limited_Interface (Iface_Id)
11177 ("progenitor & must be limited interface",
11178 Error_Node, Iface_Id);
11181 (Task_Present (Iface_Def)
11182 or else Protected_Present (Iface_Def)
11183 or else Synchronized_Present (Iface_Def))
11184 and then Nkind (N) /= N_Private_Extension_Declaration
11185 and then not Error_Posted (N)
11188 ("progenitor & must be limited interface",
11189 Error_Node, Iface_Id);
11192 -- Protected interfaces can only inherit from limited, synchronized
11193 -- or protected interfaces.
11195 elsif Nkind (N) = N_Full_Type_Declaration
11196 and then Protected_Present (Type_Def)
11198 if Limited_Present (Iface_Def)
11199 or else Synchronized_Present (Iface_Def)
11200 or else Protected_Present (Iface_Def)
11204 elsif Task_Present (Iface_Def) then
11205 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11206 & "from task interface", Error_Node);
11209 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11210 & "from non-limited interface", Error_Node);
11213 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11214 -- limited and synchronized.
11216 elsif Synchronized_Present (Type_Def) then
11217 if Limited_Present (Iface_Def)
11218 or else Synchronized_Present (Iface_Def)
11222 elsif Protected_Present (Iface_Def)
11223 and then Nkind (N) /= N_Private_Extension_Declaration
11225 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11226 & "from protected interface", Error_Node);
11228 elsif Task_Present (Iface_Def)
11229 and then Nkind (N) /= N_Private_Extension_Declaration
11231 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11232 & "from task interface", Error_Node);
11234 elsif not Is_Limited_Interface (Iface_Id) then
11235 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11236 & "from non-limited interface", Error_Node);
11239 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11240 -- synchronized or task interfaces.
11242 elsif Nkind (N) = N_Full_Type_Declaration
11243 and then Task_Present (Type_Def)
11245 if Limited_Present (Iface_Def)
11246 or else Synchronized_Present (Iface_Def)
11247 or else Task_Present (Iface_Def)
11251 elsif Protected_Present (Iface_Def) then
11252 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11253 & "protected interface", Error_Node);
11256 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11257 & "non-limited interface", Error_Node);
11262 -- Start of processing for Check_Interfaces
11265 if Is_Interface (Parent_Type) then
11266 if Is_Task_Interface (Parent_Type) then
11269 elsif Is_Protected_Interface (Parent_Type) then
11270 Is_Protected := True;
11274 if Nkind (N) = N_Private_Extension_Declaration then
11276 -- Check that progenitors are compatible with declaration
11278 Iface := First (Interface_List (Def));
11279 while Present (Iface) loop
11280 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11282 Parent_Node := Parent (Base_Type (Iface_Typ));
11283 Iface_Def := Type_Definition (Parent_Node);
11285 if not Is_Interface (Iface_Typ) then
11286 Diagnose_Interface (Iface, Iface_Typ);
11288 Check_Ifaces (Iface_Def, Iface);
11294 if Is_Task and Is_Protected then
11296 ("type cannot derive from task and protected interface", N);
11302 -- Full type declaration of derived type.
11303 -- Check compatibility with parent if it is interface type
11305 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11306 and then Is_Interface (Parent_Type)
11308 Parent_Node := Parent (Parent_Type);
11310 -- More detailed checks for interface varieties
11313 (Iface_Def => Type_Definition (Parent_Node),
11314 Error_Node => Subtype_Indication (Type_Definition (N)));
11317 Iface := First (Interface_List (Def));
11318 while Present (Iface) loop
11319 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11321 Parent_Node := Parent (Base_Type (Iface_Typ));
11322 Iface_Def := Type_Definition (Parent_Node);
11324 if not Is_Interface (Iface_Typ) then
11325 Diagnose_Interface (Iface, Iface_Typ);
11328 -- "The declaration of a specific descendant of an interface
11329 -- type freezes the interface type" RM 13.14
11331 Freeze_Before (N, Iface_Typ);
11332 Check_Ifaces (Iface_Def, Error_Node => Iface);
11338 if Is_Task and Is_Protected then
11340 ("type cannot derive from task and protected interface", N);
11342 end Check_Interfaces;
11344 ------------------------------------
11345 -- Check_Or_Process_Discriminants --
11346 ------------------------------------
11348 -- If an incomplete or private type declaration was already given for the
11349 -- type, the discriminants may have already been processed if they were
11350 -- present on the incomplete declaration. In this case a full conformance
11351 -- check has been performed in Find_Type_Name, and we then recheck here
11352 -- some properties that can't be checked on the partial view alone.
11353 -- Otherwise we call Process_Discriminants.
11355 procedure Check_Or_Process_Discriminants
11358 Prev : Entity_Id := Empty)
11361 if Has_Discriminants (T) then
11363 -- Discriminants are already set on T if they were already present
11364 -- on the partial view. Make them visible to component declarations.
11368 -- Discriminant on T (full view) referencing expr on partial view
11370 Prev_D : Entity_Id;
11371 -- Entity of corresponding discriminant on partial view
11374 -- Discriminant specification for full view, expression is
11375 -- the syntactic copy on full view (which has been checked for
11376 -- conformance with partial view), only used here to post error
11380 D := First_Discriminant (T);
11381 New_D := First (Discriminant_Specifications (N));
11382 while Present (D) loop
11383 Prev_D := Current_Entity (D);
11384 Set_Current_Entity (D);
11385 Set_Is_Immediately_Visible (D);
11386 Set_Homonym (D, Prev_D);
11388 -- Handle the case where there is an untagged partial view and
11389 -- the full view is tagged: must disallow discriminants with
11390 -- defaults, unless compiling for Ada 2012, which allows a
11391 -- limited tagged type to have defaulted discriminants (see
11392 -- AI05-0214). However, suppress error here if it was already
11393 -- reported on the default expression of the partial view.
11395 if Is_Tagged_Type (T)
11396 and then Present (Expression (Parent (D)))
11397 and then (not Is_Limited_Type (Current_Scope)
11398 or else Ada_Version < Ada_2012)
11399 and then not Error_Posted (Expression (Parent (D)))
11401 if Ada_Version >= Ada_2012 then
11403 ("discriminants of nonlimited tagged type cannot have "
11405 Expression (New_D));
11408 ("discriminants of tagged type cannot have defaults",
11409 Expression (New_D));
11413 -- Ada 2005 (AI-230): Access discriminant allowed in
11414 -- non-limited record types.
11416 if Ada_Version < Ada_2005 then
11418 -- This restriction gets applied to the full type here. It
11419 -- has already been applied earlier to the partial view.
11421 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11424 Next_Discriminant (D);
11429 elsif Present (Discriminant_Specifications (N)) then
11430 Process_Discriminants (N, Prev);
11432 end Check_Or_Process_Discriminants;
11434 ----------------------
11435 -- Check_Real_Bound --
11436 ----------------------
11438 procedure Check_Real_Bound (Bound : Node_Id) is
11440 if not Is_Real_Type (Etype (Bound)) then
11442 ("bound in real type definition must be of real type", Bound);
11444 elsif not Is_OK_Static_Expression (Bound) then
11445 Flag_Non_Static_Expr
11446 ("non-static expression used for real type bound!", Bound);
11453 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11455 Resolve (Bound, Standard_Float);
11456 end Check_Real_Bound;
11458 ------------------------------
11459 -- Complete_Private_Subtype --
11460 ------------------------------
11462 procedure Complete_Private_Subtype
11465 Full_Base : Entity_Id;
11466 Related_Nod : Node_Id)
11468 Save_Next_Entity : Entity_Id;
11469 Save_Homonym : Entity_Id;
11472 -- Set semantic attributes for (implicit) private subtype completion.
11473 -- If the full type has no discriminants, then it is a copy of the
11474 -- full view of the base. Otherwise, it is a subtype of the base with
11475 -- a possible discriminant constraint. Save and restore the original
11476 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11477 -- not corrupt the entity chain.
11479 -- Note that the type of the full view is the same entity as the type
11480 -- of the partial view. In this fashion, the subtype has access to the
11481 -- correct view of the parent.
11483 Save_Next_Entity := Next_Entity (Full);
11484 Save_Homonym := Homonym (Priv);
11486 case Ekind (Full_Base) is
11487 when E_Record_Type |
11493 Copy_Node (Priv, Full);
11495 Set_Has_Discriminants
11496 (Full, Has_Discriminants (Full_Base));
11497 Set_Has_Unknown_Discriminants
11498 (Full, Has_Unknown_Discriminants (Full_Base));
11499 Set_First_Entity (Full, First_Entity (Full_Base));
11500 Set_Last_Entity (Full, Last_Entity (Full_Base));
11502 -- If the underlying base type is constrained, we know that the
11503 -- full view of the subtype is constrained as well (the converse
11504 -- is not necessarily true).
11506 if Is_Constrained (Full_Base) then
11507 Set_Is_Constrained (Full);
11511 Copy_Node (Full_Base, Full);
11513 Set_Chars (Full, Chars (Priv));
11514 Conditional_Delay (Full, Priv);
11515 Set_Sloc (Full, Sloc (Priv));
11518 Set_Next_Entity (Full, Save_Next_Entity);
11519 Set_Homonym (Full, Save_Homonym);
11520 Set_Associated_Node_For_Itype (Full, Related_Nod);
11522 -- Set common attributes for all subtypes: kind, convention, etc.
11524 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11525 Set_Convention (Full, Convention (Full_Base));
11527 -- The Etype of the full view is inconsistent. Gigi needs to see the
11528 -- structural full view, which is what the current scheme gives: the
11529 -- Etype of the full view is the etype of the full base. However, if the
11530 -- full base is a derived type, the full view then looks like a subtype
11531 -- of the parent, not a subtype of the full base. If instead we write:
11533 -- Set_Etype (Full, Full_Base);
11535 -- then we get inconsistencies in the front-end (confusion between
11536 -- views). Several outstanding bugs are related to this ???
11538 Set_Is_First_Subtype (Full, False);
11539 Set_Scope (Full, Scope (Priv));
11540 Set_Size_Info (Full, Full_Base);
11541 Set_RM_Size (Full, RM_Size (Full_Base));
11542 Set_Is_Itype (Full);
11544 -- A subtype of a private-type-without-discriminants, whose full-view
11545 -- has discriminants with default expressions, is not constrained.
11547 if not Has_Discriminants (Priv) then
11548 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11550 if Has_Discriminants (Full_Base) then
11551 Set_Discriminant_Constraint
11552 (Full, Discriminant_Constraint (Full_Base));
11554 -- The partial view may have been indefinite, the full view
11557 Set_Has_Unknown_Discriminants
11558 (Full, Has_Unknown_Discriminants (Full_Base));
11562 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11563 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11565 -- Freeze the private subtype entity if its parent is delayed, and not
11566 -- already frozen. We skip this processing if the type is an anonymous
11567 -- subtype of a record component, or is the corresponding record of a
11568 -- protected type, since ???
11570 if not Is_Type (Scope (Full)) then
11571 Set_Has_Delayed_Freeze (Full,
11572 Has_Delayed_Freeze (Full_Base)
11573 and then (not Is_Frozen (Full_Base)));
11576 Set_Freeze_Node (Full, Empty);
11577 Set_Is_Frozen (Full, False);
11578 Set_Full_View (Priv, Full);
11580 if Has_Discriminants (Full) then
11581 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11582 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11584 if Has_Unknown_Discriminants (Full) then
11585 Set_Discriminant_Constraint (Full, No_Elist);
11589 if Ekind (Full_Base) = E_Record_Type
11590 and then Has_Discriminants (Full_Base)
11591 and then Has_Discriminants (Priv) -- might not, if errors
11592 and then not Has_Unknown_Discriminants (Priv)
11593 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11595 Create_Constrained_Components
11596 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11598 -- If the full base is itself derived from private, build a congruent
11599 -- subtype of its underlying type, for use by the back end. For a
11600 -- constrained record component, the declaration cannot be placed on
11601 -- the component list, but it must nevertheless be built an analyzed, to
11602 -- supply enough information for Gigi to compute the size of component.
11604 elsif Ekind (Full_Base) in Private_Kind
11605 and then Is_Derived_Type (Full_Base)
11606 and then Has_Discriminants (Full_Base)
11607 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11609 if not Is_Itype (Priv)
11611 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11613 Build_Underlying_Full_View
11614 (Parent (Priv), Full, Etype (Full_Base));
11616 elsif Nkind (Related_Nod) = N_Component_Declaration then
11617 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11620 elsif Is_Record_Type (Full_Base) then
11622 -- Show Full is simply a renaming of Full_Base
11624 Set_Cloned_Subtype (Full, Full_Base);
11627 -- It is unsafe to share the bounds of a scalar type, because the Itype
11628 -- is elaborated on demand, and if a bound is non-static then different
11629 -- orders of elaboration in different units will lead to different
11630 -- external symbols.
11632 if Is_Scalar_Type (Full_Base) then
11633 Set_Scalar_Range (Full,
11634 Make_Range (Sloc (Related_Nod),
11636 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11638 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11640 -- This completion inherits the bounds of the full parent, but if
11641 -- the parent is an unconstrained floating point type, so is the
11644 if Is_Floating_Point_Type (Full_Base) then
11645 Set_Includes_Infinities
11646 (Scalar_Range (Full), Has_Infinities (Full_Base));
11650 -- ??? It seems that a lot of fields are missing that should be copied
11651 -- from Full_Base to Full. Here are some that are introduced in a
11652 -- non-disruptive way but a cleanup is necessary.
11654 if Is_Tagged_Type (Full_Base) then
11655 Set_Is_Tagged_Type (Full);
11656 Set_Direct_Primitive_Operations
11657 (Full, Direct_Primitive_Operations (Full_Base));
11658 Set_No_Tagged_Streams_Pragma
11659 (Full, No_Tagged_Streams_Pragma (Full_Base));
11661 -- Inherit class_wide type of full_base in case the partial view was
11662 -- not tagged. Otherwise it has already been created when the private
11663 -- subtype was analyzed.
11665 if No (Class_Wide_Type (Full)) then
11666 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11669 -- If this is a subtype of a protected or task type, constrain its
11670 -- corresponding record, unless this is a subtype without constraints,
11671 -- i.e. a simple renaming as with an actual subtype in an instance.
11673 elsif Is_Concurrent_Type (Full_Base) then
11674 if Has_Discriminants (Full)
11675 and then Present (Corresponding_Record_Type (Full_Base))
11677 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11679 Set_Corresponding_Record_Type (Full,
11680 Constrain_Corresponding_Record
11681 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11684 Set_Corresponding_Record_Type (Full,
11685 Corresponding_Record_Type (Full_Base));
11689 -- Link rep item chain, and also setting of Has_Predicates from private
11690 -- subtype to full subtype, since we will need these on the full subtype
11691 -- to create the predicate function. Note that the full subtype may
11692 -- already have rep items, inherited from the full view of the base
11693 -- type, so we must be sure not to overwrite these entries.
11698 Next_Item : Node_Id;
11701 Item := First_Rep_Item (Full);
11703 -- If no existing rep items on full type, we can just link directly
11704 -- to the list of items on the private type. Same if the rep items
11705 -- are only those inherited from the base
11708 or else Nkind (Item) /= N_Aspect_Specification
11709 or else Entity (Item) = Full_Base
11711 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11713 -- Otherwise, search to the end of items currently linked to the full
11714 -- subtype and append the private items to the end. However, if Priv
11715 -- and Full already have the same list of rep items, then the append
11716 -- is not done, as that would create a circularity.
11718 elsif Item /= First_Rep_Item (Priv) then
11721 Next_Item := Next_Rep_Item (Item);
11722 exit when No (Next_Item);
11725 -- If the private view has aspect specifications, the full view
11726 -- inherits them. Since these aspects may already have been
11727 -- attached to the full view during derivation, do not append
11728 -- them if already present.
11730 if Item = First_Rep_Item (Priv) then
11736 -- And link the private type items at the end of the chain
11739 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11744 -- Make sure Has_Predicates is set on full type if it is set on the
11745 -- private type. Note that it may already be set on the full type and
11746 -- if so, we don't want to unset it.
11748 if Has_Predicates (Priv) then
11749 Set_Has_Predicates (Full);
11751 end Complete_Private_Subtype;
11753 ----------------------------
11754 -- Constant_Redeclaration --
11755 ----------------------------
11757 procedure Constant_Redeclaration
11762 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11763 Obj_Def : constant Node_Id := Object_Definition (N);
11766 procedure Check_Possible_Deferred_Completion
11767 (Prev_Id : Entity_Id;
11768 Prev_Obj_Def : Node_Id;
11769 Curr_Obj_Def : Node_Id);
11770 -- Determine whether the two object definitions describe the partial
11771 -- and the full view of a constrained deferred constant. Generate
11772 -- a subtype for the full view and verify that it statically matches
11773 -- the subtype of the partial view.
11775 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11776 -- If deferred constant is an access type initialized with an allocator,
11777 -- check whether there is an illegal recursion in the definition,
11778 -- through a default value of some record subcomponent. This is normally
11779 -- detected when generating init procs, but requires this additional
11780 -- mechanism when expansion is disabled.
11782 ----------------------------------------
11783 -- Check_Possible_Deferred_Completion --
11784 ----------------------------------------
11786 procedure Check_Possible_Deferred_Completion
11787 (Prev_Id : Entity_Id;
11788 Prev_Obj_Def : Node_Id;
11789 Curr_Obj_Def : Node_Id)
11792 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11793 and then Present (Constraint (Prev_Obj_Def))
11794 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11795 and then Present (Constraint (Curr_Obj_Def))
11798 Loc : constant Source_Ptr := Sloc (N);
11799 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11800 Decl : constant Node_Id :=
11801 Make_Subtype_Declaration (Loc,
11802 Defining_Identifier => Def_Id,
11803 Subtype_Indication =>
11804 Relocate_Node (Curr_Obj_Def));
11807 Insert_Before_And_Analyze (N, Decl);
11808 Set_Etype (Id, Def_Id);
11810 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11811 Error_Msg_Sloc := Sloc (Prev_Id);
11812 Error_Msg_N ("subtype does not statically match deferred "
11813 & "declaration #", N);
11817 end Check_Possible_Deferred_Completion;
11819 ---------------------------------
11820 -- Check_Recursive_Declaration --
11821 ---------------------------------
11823 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11827 if Is_Record_Type (Typ) then
11828 Comp := First_Component (Typ);
11829 while Present (Comp) loop
11830 if Comes_From_Source (Comp) then
11831 if Present (Expression (Parent (Comp)))
11832 and then Is_Entity_Name (Expression (Parent (Comp)))
11833 and then Entity (Expression (Parent (Comp))) = Prev
11835 Error_Msg_Sloc := Sloc (Parent (Comp));
11837 ("illegal circularity with declaration for & #",
11841 elsif Is_Record_Type (Etype (Comp)) then
11842 Check_Recursive_Declaration (Etype (Comp));
11846 Next_Component (Comp);
11849 end Check_Recursive_Declaration;
11851 -- Start of processing for Constant_Redeclaration
11854 if Nkind (Parent (Prev)) = N_Object_Declaration then
11855 if Nkind (Object_Definition
11856 (Parent (Prev))) = N_Subtype_Indication
11858 -- Find type of new declaration. The constraints of the two
11859 -- views must match statically, but there is no point in
11860 -- creating an itype for the full view.
11862 if Nkind (Obj_Def) = N_Subtype_Indication then
11863 Find_Type (Subtype_Mark (Obj_Def));
11864 New_T := Entity (Subtype_Mark (Obj_Def));
11867 Find_Type (Obj_Def);
11868 New_T := Entity (Obj_Def);
11874 -- The full view may impose a constraint, even if the partial
11875 -- view does not, so construct the subtype.
11877 New_T := Find_Type_Of_Object (Obj_Def, N);
11882 -- Current declaration is illegal, diagnosed below in Enter_Name
11888 -- If previous full declaration or a renaming declaration exists, or if
11889 -- a homograph is present, let Enter_Name handle it, either with an
11890 -- error or with the removal of an overridden implicit subprogram.
11891 -- The previous one is a full declaration if it has an expression
11892 -- (which in the case of an aggregate is indicated by the Init flag).
11894 if Ekind (Prev) /= E_Constant
11895 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11896 or else Present (Expression (Parent (Prev)))
11897 or else Has_Init_Expression (Parent (Prev))
11898 or else Present (Full_View (Prev))
11902 -- Verify that types of both declarations match, or else that both types
11903 -- are anonymous access types whose designated subtypes statically match
11904 -- (as allowed in Ada 2005 by AI-385).
11906 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11908 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11909 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11910 or else Is_Access_Constant (Etype (New_T)) /=
11911 Is_Access_Constant (Etype (Prev))
11912 or else Can_Never_Be_Null (Etype (New_T)) /=
11913 Can_Never_Be_Null (Etype (Prev))
11914 or else Null_Exclusion_Present (Parent (Prev)) /=
11915 Null_Exclusion_Present (Parent (Id))
11916 or else not Subtypes_Statically_Match
11917 (Designated_Type (Etype (Prev)),
11918 Designated_Type (Etype (New_T))))
11920 Error_Msg_Sloc := Sloc (Prev);
11921 Error_Msg_N ("type does not match declaration#", N);
11922 Set_Full_View (Prev, Id);
11923 Set_Etype (Id, Any_Type);
11925 -- A deferred constant whose type is an anonymous array is always
11926 -- illegal (unless imported). A detailed error message might be
11927 -- helpful for Ada beginners.
11929 if Nkind (Object_Definition (Parent (Prev)))
11930 = N_Constrained_Array_Definition
11931 and then Nkind (Object_Definition (N))
11932 = N_Constrained_Array_Definition
11934 Error_Msg_N ("\each anonymous array is a distinct type", N);
11935 Error_Msg_N ("a deferred constant must have a named type",
11936 Object_Definition (Parent (Prev)));
11940 Null_Exclusion_Present (Parent (Prev))
11941 and then not Null_Exclusion_Present (N)
11943 Error_Msg_Sloc := Sloc (Prev);
11944 Error_Msg_N ("null-exclusion does not match declaration#", N);
11945 Set_Full_View (Prev, Id);
11946 Set_Etype (Id, Any_Type);
11948 -- If so, process the full constant declaration
11951 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11952 -- the deferred declaration is constrained, then the subtype defined
11953 -- by the subtype_indication in the full declaration shall match it
11956 Check_Possible_Deferred_Completion
11958 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11959 Curr_Obj_Def => Obj_Def);
11961 Set_Full_View (Prev, Id);
11962 Set_Is_Public (Id, Is_Public (Prev));
11963 Set_Is_Internal (Id);
11964 Append_Entity (Id, Current_Scope);
11966 -- Check ALIASED present if present before (RM 7.4(7))
11968 if Is_Aliased (Prev)
11969 and then not Aliased_Present (N)
11971 Error_Msg_Sloc := Sloc (Prev);
11972 Error_Msg_N ("ALIASED required (see declaration #)", N);
11975 -- Check that placement is in private part and that the incomplete
11976 -- declaration appeared in the visible part.
11978 if Ekind (Current_Scope) = E_Package
11979 and then not In_Private_Part (Current_Scope)
11981 Error_Msg_Sloc := Sloc (Prev);
11983 ("full constant for declaration # must be in private part", N);
11985 elsif Ekind (Current_Scope) = E_Package
11987 List_Containing (Parent (Prev)) /=
11988 Visible_Declarations (Package_Specification (Current_Scope))
11991 ("deferred constant must be declared in visible part",
11995 if Is_Access_Type (T)
11996 and then Nkind (Expression (N)) = N_Allocator
11998 Check_Recursive_Declaration (Designated_Type (T));
12001 -- A deferred constant is a visible entity. If type has invariants,
12002 -- verify that the initial value satisfies them.
12004 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12006 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12009 end Constant_Redeclaration;
12011 ----------------------
12012 -- Constrain_Access --
12013 ----------------------
12015 procedure Constrain_Access
12016 (Def_Id : in out Entity_Id;
12018 Related_Nod : Node_Id)
12020 T : constant Entity_Id := Entity (Subtype_Mark (S));
12021 Desig_Type : constant Entity_Id := Designated_Type (T);
12022 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12023 Constraint_OK : Boolean := True;
12026 if Is_Array_Type (Desig_Type) then
12027 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12029 elsif (Is_Record_Type (Desig_Type)
12030 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12031 and then not Is_Constrained (Desig_Type)
12033 -- ??? The following code is a temporary bypass to ignore a
12034 -- discriminant constraint on access type if it is constraining
12035 -- the current record. Avoid creating the implicit subtype of the
12036 -- record we are currently compiling since right now, we cannot
12037 -- handle these. For now, just return the access type itself.
12039 if Desig_Type = Current_Scope
12040 and then No (Def_Id)
12042 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12043 Def_Id := Entity (Subtype_Mark (S));
12045 -- This call added to ensure that the constraint is analyzed
12046 -- (needed for a B test). Note that we still return early from
12047 -- this procedure to avoid recursive processing. ???
12049 Constrain_Discriminated_Type
12050 (Desig_Subtype, S, Related_Nod, For_Access => True);
12054 -- Enforce rule that the constraint is illegal if there is an
12055 -- unconstrained view of the designated type. This means that the
12056 -- partial view (either a private type declaration or a derivation
12057 -- from a private type) has no discriminants. (Defect Report
12058 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12060 -- Rule updated for Ada 2005: The private type is said to have
12061 -- a constrained partial view, given that objects of the type
12062 -- can be declared. Furthermore, the rule applies to all access
12063 -- types, unlike the rule concerning default discriminants (see
12066 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12067 and then Has_Private_Declaration (Desig_Type)
12068 and then In_Open_Scopes (Scope (Desig_Type))
12069 and then Has_Discriminants (Desig_Type)
12072 Pack : constant Node_Id :=
12073 Unit_Declaration_Node (Scope (Desig_Type));
12078 if Nkind (Pack) = N_Package_Declaration then
12079 Decls := Visible_Declarations (Specification (Pack));
12080 Decl := First (Decls);
12081 while Present (Decl) loop
12082 if (Nkind (Decl) = N_Private_Type_Declaration
12083 and then Chars (Defining_Identifier (Decl)) =
12084 Chars (Desig_Type))
12087 (Nkind (Decl) = N_Full_Type_Declaration
12089 Chars (Defining_Identifier (Decl)) =
12091 and then Is_Derived_Type (Desig_Type)
12093 Has_Private_Declaration (Etype (Desig_Type)))
12095 if No (Discriminant_Specifications (Decl)) then
12097 ("cannot constrain access type if designated "
12098 & "type has constrained partial view", S);
12110 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12111 For_Access => True);
12113 elsif Is_Concurrent_Type (Desig_Type)
12114 and then not Is_Constrained (Desig_Type)
12116 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12119 Error_Msg_N ("invalid constraint on access type", S);
12121 -- We simply ignore an invalid constraint
12123 Desig_Subtype := Desig_Type;
12124 Constraint_OK := False;
12127 if No (Def_Id) then
12128 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12130 Set_Ekind (Def_Id, E_Access_Subtype);
12133 if Constraint_OK then
12134 Set_Etype (Def_Id, Base_Type (T));
12136 if Is_Private_Type (Desig_Type) then
12137 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12140 Set_Etype (Def_Id, Any_Type);
12143 Set_Size_Info (Def_Id, T);
12144 Set_Is_Constrained (Def_Id, Constraint_OK);
12145 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12146 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12147 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12149 Conditional_Delay (Def_Id, T);
12151 -- AI-363 : Subtypes of general access types whose designated types have
12152 -- default discriminants are disallowed. In instances, the rule has to
12153 -- be checked against the actual, of which T is the subtype. In a
12154 -- generic body, the rule is checked assuming that the actual type has
12155 -- defaulted discriminants.
12157 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12158 if Ekind (Base_Type (T)) = E_General_Access_Type
12159 and then Has_Defaulted_Discriminants (Desig_Type)
12161 if Ada_Version < Ada_2005 then
12163 ("access subtype of general access type would not " &
12164 "be allowed in Ada 2005?y?", S);
12167 ("access subtype of general access type not allowed", S);
12170 Error_Msg_N ("\discriminants have defaults", S);
12172 elsif Is_Access_Type (T)
12173 and then Is_Generic_Type (Desig_Type)
12174 and then Has_Discriminants (Desig_Type)
12175 and then In_Package_Body (Current_Scope)
12177 if Ada_Version < Ada_2005 then
12179 ("access subtype would not be allowed in generic body "
12180 & "in Ada 2005?y?", S);
12183 ("access subtype not allowed in generic body", S);
12187 ("\designated type is a discriminated formal", S);
12190 end Constrain_Access;
12192 ---------------------
12193 -- Constrain_Array --
12194 ---------------------
12196 procedure Constrain_Array
12197 (Def_Id : in out Entity_Id;
12199 Related_Nod : Node_Id;
12200 Related_Id : Entity_Id;
12201 Suffix : Character)
12203 C : constant Node_Id := Constraint (SI);
12204 Number_Of_Constraints : Nat := 0;
12207 Constraint_OK : Boolean := True;
12210 T := Entity (Subtype_Mark (SI));
12212 if Is_Access_Type (T) then
12213 T := Designated_Type (T);
12216 -- If an index constraint follows a subtype mark in a subtype indication
12217 -- then the type or subtype denoted by the subtype mark must not already
12218 -- impose an index constraint. The subtype mark must denote either an
12219 -- unconstrained array type or an access type whose designated type
12220 -- is such an array type... (RM 3.6.1)
12222 if Is_Constrained (T) then
12223 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12224 Constraint_OK := False;
12227 S := First (Constraints (C));
12228 while Present (S) loop
12229 Number_Of_Constraints := Number_Of_Constraints + 1;
12233 -- In either case, the index constraint must provide a discrete
12234 -- range for each index of the array type and the type of each
12235 -- discrete range must be the same as that of the corresponding
12236 -- index. (RM 3.6.1)
12238 if Number_Of_Constraints /= Number_Dimensions (T) then
12239 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12240 Constraint_OK := False;
12243 S := First (Constraints (C));
12244 Index := First_Index (T);
12247 -- Apply constraints to each index type
12249 for J in 1 .. Number_Of_Constraints loop
12250 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12258 if No (Def_Id) then
12260 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12261 Set_Parent (Def_Id, Related_Nod);
12264 Set_Ekind (Def_Id, E_Array_Subtype);
12267 Set_Size_Info (Def_Id, (T));
12268 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12269 Set_Etype (Def_Id, Base_Type (T));
12271 if Constraint_OK then
12272 Set_First_Index (Def_Id, First (Constraints (C)));
12274 Set_First_Index (Def_Id, First_Index (T));
12277 Set_Is_Constrained (Def_Id, True);
12278 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12279 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12281 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12282 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12284 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12285 -- We need to initialize the attribute because if Def_Id is previously
12286 -- analyzed through a limited_with clause, it will have the attributes
12287 -- of an incomplete type, one of which is an Elist that overlaps the
12288 -- Packed_Array_Impl_Type field.
12290 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12292 -- Build a freeze node if parent still needs one. Also make sure that
12293 -- the Depends_On_Private status is set because the subtype will need
12294 -- reprocessing at the time the base type does, and also we must set a
12295 -- conditional delay.
12297 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12298 Conditional_Delay (Def_Id, T);
12299 end Constrain_Array;
12301 ------------------------------
12302 -- Constrain_Component_Type --
12303 ------------------------------
12305 function Constrain_Component_Type
12307 Constrained_Typ : Entity_Id;
12308 Related_Node : Node_Id;
12310 Constraints : Elist_Id) return Entity_Id
12312 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12313 Compon_Type : constant Entity_Id := Etype (Comp);
12315 function Build_Constrained_Array_Type
12316 (Old_Type : Entity_Id) return Entity_Id;
12317 -- If Old_Type is an array type, one of whose indexes is constrained
12318 -- by a discriminant, build an Itype whose constraint replaces the
12319 -- discriminant with its value in the constraint.
12321 function Build_Constrained_Discriminated_Type
12322 (Old_Type : Entity_Id) return Entity_Id;
12323 -- Ditto for record components
12325 function Build_Constrained_Access_Type
12326 (Old_Type : Entity_Id) return Entity_Id;
12327 -- Ditto for access types. Makes use of previous two functions, to
12328 -- constrain designated type.
12330 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12331 -- T is an array or discriminated type, C is a list of constraints
12332 -- that apply to T. This routine builds the constrained subtype.
12334 function Is_Discriminant (Expr : Node_Id) return Boolean;
12335 -- Returns True if Expr is a discriminant
12337 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12338 -- Find the value of discriminant Discrim in Constraint
12340 -----------------------------------
12341 -- Build_Constrained_Access_Type --
12342 -----------------------------------
12344 function Build_Constrained_Access_Type
12345 (Old_Type : Entity_Id) return Entity_Id
12347 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12349 Desig_Subtype : Entity_Id;
12353 -- if the original access type was not embedded in the enclosing
12354 -- type definition, there is no need to produce a new access
12355 -- subtype. In fact every access type with an explicit constraint
12356 -- generates an itype whose scope is the enclosing record.
12358 if not Is_Type (Scope (Old_Type)) then
12361 elsif Is_Array_Type (Desig_Type) then
12362 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12364 elsif Has_Discriminants (Desig_Type) then
12366 -- This may be an access type to an enclosing record type for
12367 -- which we are constructing the constrained components. Return
12368 -- the enclosing record subtype. This is not always correct,
12369 -- but avoids infinite recursion. ???
12371 Desig_Subtype := Any_Type;
12373 for J in reverse 0 .. Scope_Stack.Last loop
12374 Scop := Scope_Stack.Table (J).Entity;
12377 and then Base_Type (Scop) = Base_Type (Desig_Type)
12379 Desig_Subtype := Scop;
12382 exit when not Is_Type (Scop);
12385 if Desig_Subtype = Any_Type then
12387 Build_Constrained_Discriminated_Type (Desig_Type);
12394 if Desig_Subtype /= Desig_Type then
12396 -- The Related_Node better be here or else we won't be able
12397 -- to attach new itypes to a node in the tree.
12399 pragma Assert (Present (Related_Node));
12401 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12403 Set_Etype (Itype, Base_Type (Old_Type));
12404 Set_Size_Info (Itype, (Old_Type));
12405 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12406 Set_Depends_On_Private (Itype, Has_Private_Component
12408 Set_Is_Access_Constant (Itype, Is_Access_Constant
12411 -- The new itype needs freezing when it depends on a not frozen
12412 -- type and the enclosing subtype needs freezing.
12414 if Has_Delayed_Freeze (Constrained_Typ)
12415 and then not Is_Frozen (Constrained_Typ)
12417 Conditional_Delay (Itype, Base_Type (Old_Type));
12425 end Build_Constrained_Access_Type;
12427 ----------------------------------
12428 -- Build_Constrained_Array_Type --
12429 ----------------------------------
12431 function Build_Constrained_Array_Type
12432 (Old_Type : Entity_Id) return Entity_Id
12436 Old_Index : Node_Id;
12437 Range_Node : Node_Id;
12438 Constr_List : List_Id;
12440 Need_To_Create_Itype : Boolean := False;
12443 Old_Index := First_Index (Old_Type);
12444 while Present (Old_Index) loop
12445 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12447 if Is_Discriminant (Lo_Expr)
12449 Is_Discriminant (Hi_Expr)
12451 Need_To_Create_Itype := True;
12454 Next_Index (Old_Index);
12457 if Need_To_Create_Itype then
12458 Constr_List := New_List;
12460 Old_Index := First_Index (Old_Type);
12461 while Present (Old_Index) loop
12462 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12464 if Is_Discriminant (Lo_Expr) then
12465 Lo_Expr := Get_Discr_Value (Lo_Expr);
12468 if Is_Discriminant (Hi_Expr) then
12469 Hi_Expr := Get_Discr_Value (Hi_Expr);
12474 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12476 Append (Range_Node, To => Constr_List);
12478 Next_Index (Old_Index);
12481 return Build_Subtype (Old_Type, Constr_List);
12486 end Build_Constrained_Array_Type;
12488 ------------------------------------------
12489 -- Build_Constrained_Discriminated_Type --
12490 ------------------------------------------
12492 function Build_Constrained_Discriminated_Type
12493 (Old_Type : Entity_Id) return Entity_Id
12496 Constr_List : List_Id;
12497 Old_Constraint : Elmt_Id;
12499 Need_To_Create_Itype : Boolean := False;
12502 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12503 while Present (Old_Constraint) loop
12504 Expr := Node (Old_Constraint);
12506 if Is_Discriminant (Expr) then
12507 Need_To_Create_Itype := True;
12510 Next_Elmt (Old_Constraint);
12513 if Need_To_Create_Itype then
12514 Constr_List := New_List;
12516 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12517 while Present (Old_Constraint) loop
12518 Expr := Node (Old_Constraint);
12520 if Is_Discriminant (Expr) then
12521 Expr := Get_Discr_Value (Expr);
12524 Append (New_Copy_Tree (Expr), To => Constr_List);
12526 Next_Elmt (Old_Constraint);
12529 return Build_Subtype (Old_Type, Constr_List);
12534 end Build_Constrained_Discriminated_Type;
12536 -------------------
12537 -- Build_Subtype --
12538 -------------------
12540 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12542 Subtyp_Decl : Node_Id;
12543 Def_Id : Entity_Id;
12544 Btyp : Entity_Id := Base_Type (T);
12547 -- The Related_Node better be here or else we won't be able to
12548 -- attach new itypes to a node in the tree.
12550 pragma Assert (Present (Related_Node));
12552 -- If the view of the component's type is incomplete or private
12553 -- with unknown discriminants, then the constraint must be applied
12554 -- to the full type.
12556 if Has_Unknown_Discriminants (Btyp)
12557 and then Present (Underlying_Type (Btyp))
12559 Btyp := Underlying_Type (Btyp);
12563 Make_Subtype_Indication (Loc,
12564 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12565 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12567 Def_Id := Create_Itype (Ekind (T), Related_Node);
12570 Make_Subtype_Declaration (Loc,
12571 Defining_Identifier => Def_Id,
12572 Subtype_Indication => Indic);
12574 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12576 -- Itypes must be analyzed with checks off (see package Itypes)
12578 Analyze (Subtyp_Decl, Suppress => All_Checks);
12583 ---------------------
12584 -- Get_Discr_Value --
12585 ---------------------
12587 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12592 -- The discriminant may be declared for the type, in which case we
12593 -- find it by iterating over the list of discriminants. If the
12594 -- discriminant is inherited from a parent type, it appears as the
12595 -- corresponding discriminant of the current type. This will be the
12596 -- case when constraining an inherited component whose constraint is
12597 -- given by a discriminant of the parent.
12599 D := First_Discriminant (Typ);
12600 E := First_Elmt (Constraints);
12602 while Present (D) loop
12603 if D = Entity (Discrim)
12604 or else D = CR_Discriminant (Entity (Discrim))
12605 or else Corresponding_Discriminant (D) = Entity (Discrim)
12610 Next_Discriminant (D);
12614 -- The Corresponding_Discriminant mechanism is incomplete, because
12615 -- the correspondence between new and old discriminants is not one
12616 -- to one: one new discriminant can constrain several old ones. In
12617 -- that case, scan sequentially the stored_constraint, the list of
12618 -- discriminants of the parents, and the constraints.
12620 -- Previous code checked for the present of the Stored_Constraint
12621 -- list for the derived type, but did not use it at all. Should it
12622 -- be present when the component is a discriminated task type?
12624 if Is_Derived_Type (Typ)
12625 and then Scope (Entity (Discrim)) = Etype (Typ)
12627 D := First_Discriminant (Etype (Typ));
12628 E := First_Elmt (Constraints);
12629 while Present (D) loop
12630 if D = Entity (Discrim) then
12634 Next_Discriminant (D);
12639 -- Something is wrong if we did not find the value
12641 raise Program_Error;
12642 end Get_Discr_Value;
12644 ---------------------
12645 -- Is_Discriminant --
12646 ---------------------
12648 function Is_Discriminant (Expr : Node_Id) return Boolean is
12649 Discrim_Scope : Entity_Id;
12652 if Denotes_Discriminant (Expr) then
12653 Discrim_Scope := Scope (Entity (Expr));
12655 -- Either we have a reference to one of Typ's discriminants,
12657 pragma Assert (Discrim_Scope = Typ
12659 -- or to the discriminants of the parent type, in the case
12660 -- of a derivation of a tagged type with variants.
12662 or else Discrim_Scope = Etype (Typ)
12663 or else Full_View (Discrim_Scope) = Etype (Typ)
12665 -- or same as above for the case where the discriminants
12666 -- were declared in Typ's private view.
12668 or else (Is_Private_Type (Discrim_Scope)
12669 and then Chars (Discrim_Scope) = Chars (Typ))
12671 -- or else we are deriving from the full view and the
12672 -- discriminant is declared in the private entity.
12674 or else (Is_Private_Type (Typ)
12675 and then Chars (Discrim_Scope) = Chars (Typ))
12677 -- Or we are constrained the corresponding record of a
12678 -- synchronized type that completes a private declaration.
12680 or else (Is_Concurrent_Record_Type (Typ)
12682 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12684 -- or we have a class-wide type, in which case make sure the
12685 -- discriminant found belongs to the root type.
12687 or else (Is_Class_Wide_Type (Typ)
12688 and then Etype (Typ) = Discrim_Scope));
12693 -- In all other cases we have something wrong
12696 end Is_Discriminant;
12698 -- Start of processing for Constrain_Component_Type
12701 if Nkind (Parent (Comp)) = N_Component_Declaration
12702 and then Comes_From_Source (Parent (Comp))
12703 and then Comes_From_Source
12704 (Subtype_Indication (Component_Definition (Parent (Comp))))
12707 (Subtype_Indication (Component_Definition (Parent (Comp))))
12709 return Compon_Type;
12711 elsif Is_Array_Type (Compon_Type) then
12712 return Build_Constrained_Array_Type (Compon_Type);
12714 elsif Has_Discriminants (Compon_Type) then
12715 return Build_Constrained_Discriminated_Type (Compon_Type);
12717 elsif Is_Access_Type (Compon_Type) then
12718 return Build_Constrained_Access_Type (Compon_Type);
12721 return Compon_Type;
12723 end Constrain_Component_Type;
12725 --------------------------
12726 -- Constrain_Concurrent --
12727 --------------------------
12729 -- For concurrent types, the associated record value type carries the same
12730 -- discriminants, so when we constrain a concurrent type, we must constrain
12731 -- the corresponding record type as well.
12733 procedure Constrain_Concurrent
12734 (Def_Id : in out Entity_Id;
12736 Related_Nod : Node_Id;
12737 Related_Id : Entity_Id;
12738 Suffix : Character)
12740 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12741 -- case of a private subtype (needed when only doing semantic analysis).
12743 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12747 if Is_Access_Type (T_Ent) then
12748 T_Ent := Designated_Type (T_Ent);
12751 T_Val := Corresponding_Record_Type (T_Ent);
12753 if Present (T_Val) then
12755 if No (Def_Id) then
12756 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12759 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12761 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12762 Set_Corresponding_Record_Type (Def_Id,
12763 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12766 -- If there is no associated record, expansion is disabled and this
12767 -- is a generic context. Create a subtype in any case, so that
12768 -- semantic analysis can proceed.
12770 if No (Def_Id) then
12771 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12774 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12776 end Constrain_Concurrent;
12778 ------------------------------------
12779 -- Constrain_Corresponding_Record --
12780 ------------------------------------
12782 function Constrain_Corresponding_Record
12783 (Prot_Subt : Entity_Id;
12784 Corr_Rec : Entity_Id;
12785 Related_Nod : Node_Id) return Entity_Id
12787 T_Sub : constant Entity_Id :=
12788 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12791 Set_Etype (T_Sub, Corr_Rec);
12792 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12793 Set_Is_Constrained (T_Sub, True);
12794 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12795 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12797 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12798 Set_Discriminant_Constraint
12799 (T_Sub, Discriminant_Constraint (Prot_Subt));
12800 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12801 Create_Constrained_Components
12802 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12805 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12807 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12808 Conditional_Delay (T_Sub, Corr_Rec);
12811 -- This is a component subtype: it will be frozen in the context of
12812 -- the enclosing record's init_proc, so that discriminant references
12813 -- are resolved to discriminals. (Note: we used to skip freezing
12814 -- altogether in that case, which caused errors downstream for
12815 -- components of a bit packed array type).
12817 Set_Has_Delayed_Freeze (T_Sub);
12821 end Constrain_Corresponding_Record;
12823 -----------------------
12824 -- Constrain_Decimal --
12825 -----------------------
12827 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12828 T : constant Entity_Id := Entity (Subtype_Mark (S));
12829 C : constant Node_Id := Constraint (S);
12830 Loc : constant Source_Ptr := Sloc (C);
12831 Range_Expr : Node_Id;
12832 Digits_Expr : Node_Id;
12837 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12839 if Nkind (C) = N_Range_Constraint then
12840 Range_Expr := Range_Expression (C);
12841 Digits_Val := Digits_Value (T);
12844 pragma Assert (Nkind (C) = N_Digits_Constraint);
12846 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12848 Digits_Expr := Digits_Expression (C);
12849 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12851 Check_Digits_Expression (Digits_Expr);
12852 Digits_Val := Expr_Value (Digits_Expr);
12854 if Digits_Val > Digits_Value (T) then
12856 ("digits expression is incompatible with subtype", C);
12857 Digits_Val := Digits_Value (T);
12860 if Present (Range_Constraint (C)) then
12861 Range_Expr := Range_Expression (Range_Constraint (C));
12863 Range_Expr := Empty;
12867 Set_Etype (Def_Id, Base_Type (T));
12868 Set_Size_Info (Def_Id, (T));
12869 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12870 Set_Delta_Value (Def_Id, Delta_Value (T));
12871 Set_Scale_Value (Def_Id, Scale_Value (T));
12872 Set_Small_Value (Def_Id, Small_Value (T));
12873 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12874 Set_Digits_Value (Def_Id, Digits_Val);
12876 -- Manufacture range from given digits value if no range present
12878 if No (Range_Expr) then
12879 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12883 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12885 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12888 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12889 Set_Discrete_RM_Size (Def_Id);
12891 -- Unconditionally delay the freeze, since we cannot set size
12892 -- information in all cases correctly until the freeze point.
12894 Set_Has_Delayed_Freeze (Def_Id);
12895 end Constrain_Decimal;
12897 ----------------------------------
12898 -- Constrain_Discriminated_Type --
12899 ----------------------------------
12901 procedure Constrain_Discriminated_Type
12902 (Def_Id : Entity_Id;
12904 Related_Nod : Node_Id;
12905 For_Access : Boolean := False)
12907 E : constant Entity_Id := Entity (Subtype_Mark (S));
12910 Elist : Elist_Id := New_Elmt_List;
12912 procedure Fixup_Bad_Constraint;
12913 -- This is called after finding a bad constraint, and after having
12914 -- posted an appropriate error message. The mission is to leave the
12915 -- entity T in as reasonable state as possible.
12917 --------------------------
12918 -- Fixup_Bad_Constraint --
12919 --------------------------
12921 procedure Fixup_Bad_Constraint is
12923 -- Set a reasonable Ekind for the entity. For an incomplete type,
12924 -- we can't do much, but for other types, we can set the proper
12925 -- corresponding subtype kind.
12927 if Ekind (T) = E_Incomplete_Type then
12928 Set_Ekind (Def_Id, Ekind (T));
12930 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12933 -- Set Etype to the known type, to reduce chances of cascaded errors
12935 Set_Etype (Def_Id, E);
12936 Set_Error_Posted (Def_Id);
12937 end Fixup_Bad_Constraint;
12939 -- Start of processing for Constrain_Discriminated_Type
12942 C := Constraint (S);
12944 -- A discriminant constraint is only allowed in a subtype indication,
12945 -- after a subtype mark. This subtype mark must denote either a type
12946 -- with discriminants, or an access type whose designated type is a
12947 -- type with discriminants. A discriminant constraint specifies the
12948 -- values of these discriminants (RM 3.7.2(5)).
12950 T := Base_Type (Entity (Subtype_Mark (S)));
12952 if Is_Access_Type (T) then
12953 T := Designated_Type (T);
12956 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12957 -- Avoid generating an error for access-to-incomplete subtypes.
12959 if Ada_Version >= Ada_2005
12960 and then Ekind (T) = E_Incomplete_Type
12961 and then Nkind (Parent (S)) = N_Subtype_Declaration
12962 and then not Is_Itype (Def_Id)
12964 -- A little sanity check, emit an error message if the type
12965 -- has discriminants to begin with. Type T may be a regular
12966 -- incomplete type or imported via a limited with clause.
12968 if Has_Discriminants (T)
12969 or else (From_Limited_With (T)
12970 and then Present (Non_Limited_View (T))
12971 and then Nkind (Parent (Non_Limited_View (T))) =
12972 N_Full_Type_Declaration
12973 and then Present (Discriminant_Specifications
12974 (Parent (Non_Limited_View (T)))))
12977 ("(Ada 2005) incomplete subtype may not be constrained", C);
12979 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12982 Fixup_Bad_Constraint;
12985 -- Check that the type has visible discriminants. The type may be
12986 -- a private type with unknown discriminants whose full view has
12987 -- discriminants which are invisible.
12989 elsif not Has_Discriminants (T)
12991 (Has_Unknown_Discriminants (T)
12992 and then Is_Private_Type (T))
12994 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12995 Fixup_Bad_Constraint;
12998 elsif Is_Constrained (E)
12999 or else (Ekind (E) = E_Class_Wide_Subtype
13000 and then Present (Discriminant_Constraint (E)))
13002 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13003 Fixup_Bad_Constraint;
13007 -- T may be an unconstrained subtype (e.g. a generic actual).
13008 -- Constraint applies to the base type.
13010 T := Base_Type (T);
13012 Elist := Build_Discriminant_Constraints (T, S);
13014 -- If the list returned was empty we had an error in building the
13015 -- discriminant constraint. We have also already signalled an error
13016 -- in the incomplete type case
13018 if Is_Empty_Elmt_List (Elist) then
13019 Fixup_Bad_Constraint;
13023 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13024 end Constrain_Discriminated_Type;
13026 ---------------------------
13027 -- Constrain_Enumeration --
13028 ---------------------------
13030 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13031 T : constant Entity_Id := Entity (Subtype_Mark (S));
13032 C : constant Node_Id := Constraint (S);
13035 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13037 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13039 Set_Etype (Def_Id, Base_Type (T));
13040 Set_Size_Info (Def_Id, (T));
13041 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13042 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13044 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13046 Set_Discrete_RM_Size (Def_Id);
13047 end Constrain_Enumeration;
13049 ----------------------
13050 -- Constrain_Float --
13051 ----------------------
13053 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13054 T : constant Entity_Id := Entity (Subtype_Mark (S));
13060 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13062 Set_Etype (Def_Id, Base_Type (T));
13063 Set_Size_Info (Def_Id, (T));
13064 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13066 -- Process the constraint
13068 C := Constraint (S);
13070 -- Digits constraint present
13072 if Nkind (C) = N_Digits_Constraint then
13074 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13075 Check_Restriction (No_Obsolescent_Features, C);
13077 if Warn_On_Obsolescent_Feature then
13079 ("subtype digits constraint is an " &
13080 "obsolescent feature (RM J.3(8))?j?", C);
13083 D := Digits_Expression (C);
13084 Analyze_And_Resolve (D, Any_Integer);
13085 Check_Digits_Expression (D);
13086 Set_Digits_Value (Def_Id, Expr_Value (D));
13088 -- Check that digits value is in range. Obviously we can do this
13089 -- at compile time, but it is strictly a runtime check, and of
13090 -- course there is an ACVC test that checks this.
13092 if Digits_Value (Def_Id) > Digits_Value (T) then
13093 Error_Msg_Uint_1 := Digits_Value (T);
13094 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13096 Make_Raise_Constraint_Error (Sloc (D),
13097 Reason => CE_Range_Check_Failed);
13098 Insert_Action (Declaration_Node (Def_Id), Rais);
13101 C := Range_Constraint (C);
13103 -- No digits constraint present
13106 Set_Digits_Value (Def_Id, Digits_Value (T));
13109 -- Range constraint present
13111 if Nkind (C) = N_Range_Constraint then
13112 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13114 -- No range constraint present
13117 pragma Assert (No (C));
13118 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13121 Set_Is_Constrained (Def_Id);
13122 end Constrain_Float;
13124 ---------------------
13125 -- Constrain_Index --
13126 ---------------------
13128 procedure Constrain_Index
13131 Related_Nod : Node_Id;
13132 Related_Id : Entity_Id;
13133 Suffix : Character;
13134 Suffix_Index : Nat)
13136 Def_Id : Entity_Id;
13137 R : Node_Id := Empty;
13138 T : constant Entity_Id := Etype (Index);
13141 if Nkind (S) = N_Range
13143 (Nkind (S) = N_Attribute_Reference
13144 and then Attribute_Name (S) = Name_Range)
13146 -- A Range attribute will be transformed into N_Range by Resolve
13152 Process_Range_Expr_In_Decl (R, T);
13154 if not Error_Posted (S)
13156 (Nkind (S) /= N_Range
13157 or else not Covers (T, (Etype (Low_Bound (S))))
13158 or else not Covers (T, (Etype (High_Bound (S)))))
13160 if Base_Type (T) /= Any_Type
13161 and then Etype (Low_Bound (S)) /= Any_Type
13162 and then Etype (High_Bound (S)) /= Any_Type
13164 Error_Msg_N ("range expected", S);
13168 elsif Nkind (S) = N_Subtype_Indication then
13170 -- The parser has verified that this is a discrete indication
13172 Resolve_Discrete_Subtype_Indication (S, T);
13173 Bad_Predicated_Subtype_Use
13174 ("subtype& has predicate, not allowed in index constraint",
13175 S, Entity (Subtype_Mark (S)));
13177 R := Range_Expression (Constraint (S));
13179 -- Capture values of bounds and generate temporaries for them if
13180 -- needed, since checks may cause duplication of the expressions
13181 -- which must not be reevaluated.
13183 -- The forced evaluation removes side effects from expressions, which
13184 -- should occur also in GNATprove mode. Otherwise, we end up with
13185 -- unexpected insertions of actions at places where this is not
13186 -- supposed to occur, e.g. on default parameters of a call.
13188 if Expander_Active or GNATprove_Mode then
13189 Force_Evaluation (Low_Bound (R));
13190 Force_Evaluation (High_Bound (R));
13193 elsif Nkind (S) = N_Discriminant_Association then
13195 -- Syntactically valid in subtype indication
13197 Error_Msg_N ("invalid index constraint", S);
13198 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13201 -- Subtype_Mark case, no anonymous subtypes to construct
13206 if Is_Entity_Name (S) then
13207 if not Is_Type (Entity (S)) then
13208 Error_Msg_N ("expect subtype mark for index constraint", S);
13210 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13211 Wrong_Type (S, Base_Type (T));
13213 -- Check error of subtype with predicate in index constraint
13216 Bad_Predicated_Subtype_Use
13217 ("subtype& has predicate, not allowed in index constraint",
13224 Error_Msg_N ("invalid index constraint", S);
13225 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13231 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13233 Set_Etype (Def_Id, Base_Type (T));
13235 if Is_Modular_Integer_Type (T) then
13236 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13238 elsif Is_Integer_Type (T) then
13239 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13242 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13243 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13244 Set_First_Literal (Def_Id, First_Literal (T));
13247 Set_Size_Info (Def_Id, (T));
13248 Set_RM_Size (Def_Id, RM_Size (T));
13249 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13251 Set_Scalar_Range (Def_Id, R);
13253 Set_Etype (S, Def_Id);
13254 Set_Discrete_RM_Size (Def_Id);
13255 end Constrain_Index;
13257 -----------------------
13258 -- Constrain_Integer --
13259 -----------------------
13261 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13262 T : constant Entity_Id := Entity (Subtype_Mark (S));
13263 C : constant Node_Id := Constraint (S);
13266 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13268 if Is_Modular_Integer_Type (T) then
13269 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13271 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13274 Set_Etype (Def_Id, Base_Type (T));
13275 Set_Size_Info (Def_Id, (T));
13276 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13277 Set_Discrete_RM_Size (Def_Id);
13278 end Constrain_Integer;
13280 ------------------------------
13281 -- Constrain_Ordinary_Fixed --
13282 ------------------------------
13284 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13285 T : constant Entity_Id := Entity (Subtype_Mark (S));
13291 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13292 Set_Etype (Def_Id, Base_Type (T));
13293 Set_Size_Info (Def_Id, (T));
13294 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13295 Set_Small_Value (Def_Id, Small_Value (T));
13297 -- Process the constraint
13299 C := Constraint (S);
13301 -- Delta constraint present
13303 if Nkind (C) = N_Delta_Constraint then
13305 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13306 Check_Restriction (No_Obsolescent_Features, C);
13308 if Warn_On_Obsolescent_Feature then
13310 ("subtype delta constraint is an " &
13311 "obsolescent feature (RM J.3(7))?j?");
13314 D := Delta_Expression (C);
13315 Analyze_And_Resolve (D, Any_Real);
13316 Check_Delta_Expression (D);
13317 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13319 -- Check that delta value is in range. Obviously we can do this
13320 -- at compile time, but it is strictly a runtime check, and of
13321 -- course there is an ACVC test that checks this.
13323 if Delta_Value (Def_Id) < Delta_Value (T) then
13324 Error_Msg_N ("??delta value is too small", D);
13326 Make_Raise_Constraint_Error (Sloc (D),
13327 Reason => CE_Range_Check_Failed);
13328 Insert_Action (Declaration_Node (Def_Id), Rais);
13331 C := Range_Constraint (C);
13333 -- No delta constraint present
13336 Set_Delta_Value (Def_Id, Delta_Value (T));
13339 -- Range constraint present
13341 if Nkind (C) = N_Range_Constraint then
13342 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13344 -- No range constraint present
13347 pragma Assert (No (C));
13348 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13352 Set_Discrete_RM_Size (Def_Id);
13354 -- Unconditionally delay the freeze, since we cannot set size
13355 -- information in all cases correctly until the freeze point.
13357 Set_Has_Delayed_Freeze (Def_Id);
13358 end Constrain_Ordinary_Fixed;
13360 -----------------------
13361 -- Contain_Interface --
13362 -----------------------
13364 function Contain_Interface
13365 (Iface : Entity_Id;
13366 Ifaces : Elist_Id) return Boolean
13368 Iface_Elmt : Elmt_Id;
13371 if Present (Ifaces) then
13372 Iface_Elmt := First_Elmt (Ifaces);
13373 while Present (Iface_Elmt) loop
13374 if Node (Iface_Elmt) = Iface then
13378 Next_Elmt (Iface_Elmt);
13383 end Contain_Interface;
13385 ---------------------------
13386 -- Convert_Scalar_Bounds --
13387 ---------------------------
13389 procedure Convert_Scalar_Bounds
13391 Parent_Type : Entity_Id;
13392 Derived_Type : Entity_Id;
13395 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13402 -- Defend against previous errors
13404 if No (Scalar_Range (Derived_Type)) then
13405 Check_Error_Detected;
13409 Lo := Build_Scalar_Bound
13410 (Type_Low_Bound (Derived_Type),
13411 Parent_Type, Implicit_Base);
13413 Hi := Build_Scalar_Bound
13414 (Type_High_Bound (Derived_Type),
13415 Parent_Type, Implicit_Base);
13422 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13424 Set_Parent (Rng, N);
13425 Set_Scalar_Range (Derived_Type, Rng);
13427 -- Analyze the bounds
13429 Analyze_And_Resolve (Lo, Implicit_Base);
13430 Analyze_And_Resolve (Hi, Implicit_Base);
13432 -- Analyze the range itself, except that we do not analyze it if
13433 -- the bounds are real literals, and we have a fixed-point type.
13434 -- The reason for this is that we delay setting the bounds in this
13435 -- case till we know the final Small and Size values (see circuit
13436 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13438 if Is_Fixed_Point_Type (Parent_Type)
13439 and then Nkind (Lo) = N_Real_Literal
13440 and then Nkind (Hi) = N_Real_Literal
13444 -- Here we do the analysis of the range
13446 -- Note: we do this manually, since if we do a normal Analyze and
13447 -- Resolve call, there are problems with the conversions used for
13448 -- the derived type range.
13451 Set_Etype (Rng, Implicit_Base);
13452 Set_Analyzed (Rng, True);
13454 end Convert_Scalar_Bounds;
13456 -------------------
13457 -- Copy_And_Swap --
13458 -------------------
13460 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13462 -- Initialize new full declaration entity by copying the pertinent
13463 -- fields of the corresponding private declaration entity.
13465 -- We temporarily set Ekind to a value appropriate for a type to
13466 -- avoid assert failures in Einfo from checking for setting type
13467 -- attributes on something that is not a type. Ekind (Priv) is an
13468 -- appropriate choice, since it allowed the attributes to be set
13469 -- in the first place. This Ekind value will be modified later.
13471 Set_Ekind (Full, Ekind (Priv));
13473 -- Also set Etype temporarily to Any_Type, again, in the absence
13474 -- of errors, it will be properly reset, and if there are errors,
13475 -- then we want a value of Any_Type to remain.
13477 Set_Etype (Full, Any_Type);
13479 -- Now start copying attributes
13481 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13483 if Has_Discriminants (Full) then
13484 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13485 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13488 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13489 Set_Homonym (Full, Homonym (Priv));
13490 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13491 Set_Is_Public (Full, Is_Public (Priv));
13492 Set_Is_Pure (Full, Is_Pure (Priv));
13493 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13494 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13495 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13496 Set_Has_Pragma_Unreferenced_Objects
13497 (Full, Has_Pragma_Unreferenced_Objects
13500 Conditional_Delay (Full, Priv);
13502 if Is_Tagged_Type (Full) then
13503 Set_Direct_Primitive_Operations
13504 (Full, Direct_Primitive_Operations (Priv));
13505 Set_No_Tagged_Streams_Pragma
13506 (Full, No_Tagged_Streams_Pragma (Priv));
13508 if Is_Base_Type (Priv) then
13509 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13513 Set_Is_Volatile (Full, Is_Volatile (Priv));
13514 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13515 Set_Scope (Full, Scope (Priv));
13516 Set_Next_Entity (Full, Next_Entity (Priv));
13517 Set_First_Entity (Full, First_Entity (Priv));
13518 Set_Last_Entity (Full, Last_Entity (Priv));
13520 -- If access types have been recorded for later handling, keep them in
13521 -- the full view so that they get handled when the full view freeze
13522 -- node is expanded.
13524 if Present (Freeze_Node (Priv))
13525 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13527 Ensure_Freeze_Node (Full);
13528 Set_Access_Types_To_Process
13529 (Freeze_Node (Full),
13530 Access_Types_To_Process (Freeze_Node (Priv)));
13533 -- Swap the two entities. Now Private is the full type entity and Full
13534 -- is the private one. They will be swapped back at the end of the
13535 -- private part. This swapping ensures that the entity that is visible
13536 -- in the private part is the full declaration.
13538 Exchange_Entities (Priv, Full);
13539 Append_Entity (Full, Scope (Full));
13542 -------------------------------------
13543 -- Copy_Array_Base_Type_Attributes --
13544 -------------------------------------
13546 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13548 Set_Component_Alignment (T1, Component_Alignment (T2));
13549 Set_Component_Type (T1, Component_Type (T2));
13550 Set_Component_Size (T1, Component_Size (T2));
13551 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13552 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13553 Set_Has_Protected (T1, Has_Protected (T2));
13554 Set_Has_Task (T1, Has_Task (T2));
13555 Set_Is_Packed (T1, Is_Packed (T2));
13556 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13557 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13558 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13559 end Copy_Array_Base_Type_Attributes;
13561 -----------------------------------
13562 -- Copy_Array_Subtype_Attributes --
13563 -----------------------------------
13565 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13567 Set_Size_Info (T1, T2);
13569 Set_First_Index (T1, First_Index (T2));
13570 Set_Is_Aliased (T1, Is_Aliased (T2));
13571 Set_Is_Volatile (T1, Is_Volatile (T2));
13572 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13573 Set_Is_Constrained (T1, Is_Constrained (T2));
13574 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13575 Inherit_Rep_Item_Chain (T1, T2);
13576 Set_Convention (T1, Convention (T2));
13577 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13578 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13579 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13580 end Copy_Array_Subtype_Attributes;
13582 -----------------------------------
13583 -- Create_Constrained_Components --
13584 -----------------------------------
13586 procedure Create_Constrained_Components
13588 Decl_Node : Node_Id;
13590 Constraints : Elist_Id)
13592 Loc : constant Source_Ptr := Sloc (Subt);
13593 Comp_List : constant Elist_Id := New_Elmt_List;
13594 Parent_Type : constant Entity_Id := Etype (Typ);
13595 Assoc_List : constant List_Id := New_List;
13596 Discr_Val : Elmt_Id;
13600 Is_Static : Boolean := True;
13602 procedure Collect_Fixed_Components (Typ : Entity_Id);
13603 -- Collect parent type components that do not appear in a variant part
13605 procedure Create_All_Components;
13606 -- Iterate over Comp_List to create the components of the subtype
13608 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13609 -- Creates a new component from Old_Compon, copying all the fields from
13610 -- it, including its Etype, inserts the new component in the Subt entity
13611 -- chain and returns the new component.
13613 function Is_Variant_Record (T : Entity_Id) return Boolean;
13614 -- If true, and discriminants are static, collect only components from
13615 -- variants selected by discriminant values.
13617 ------------------------------
13618 -- Collect_Fixed_Components --
13619 ------------------------------
13621 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13623 -- Build association list for discriminants, and find components of the
13624 -- variant part selected by the values of the discriminants.
13626 Old_C := First_Discriminant (Typ);
13627 Discr_Val := First_Elmt (Constraints);
13628 while Present (Old_C) loop
13629 Append_To (Assoc_List,
13630 Make_Component_Association (Loc,
13631 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13632 Expression => New_Copy (Node (Discr_Val))));
13634 Next_Elmt (Discr_Val);
13635 Next_Discriminant (Old_C);
13638 -- The tag and the possible parent component are unconditionally in
13641 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13642 Old_C := First_Component (Typ);
13643 while Present (Old_C) loop
13644 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13645 Append_Elmt (Old_C, Comp_List);
13648 Next_Component (Old_C);
13651 end Collect_Fixed_Components;
13653 ---------------------------
13654 -- Create_All_Components --
13655 ---------------------------
13657 procedure Create_All_Components is
13661 Comp := First_Elmt (Comp_List);
13662 while Present (Comp) loop
13663 Old_C := Node (Comp);
13664 New_C := Create_Component (Old_C);
13668 Constrain_Component_Type
13669 (Old_C, Subt, Decl_Node, Typ, Constraints));
13670 Set_Is_Public (New_C, Is_Public (Subt));
13674 end Create_All_Components;
13676 ----------------------
13677 -- Create_Component --
13678 ----------------------
13680 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13681 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13684 if Ekind (Old_Compon) = E_Discriminant
13685 and then Is_Completely_Hidden (Old_Compon)
13687 -- This is a shadow discriminant created for a discriminant of
13688 -- the parent type, which needs to be present in the subtype.
13689 -- Give the shadow discriminant an internal name that cannot
13690 -- conflict with that of visible components.
13692 Set_Chars (New_Compon, New_Internal_Name ('C'));
13695 -- Set the parent so we have a proper link for freezing etc. This is
13696 -- not a real parent pointer, since of course our parent does not own
13697 -- up to us and reference us, we are an illegitimate child of the
13698 -- original parent.
13700 Set_Parent (New_Compon, Parent (Old_Compon));
13702 -- If the old component's Esize was already determined and is a
13703 -- static value, then the new component simply inherits it. Otherwise
13704 -- the old component's size may require run-time determination, but
13705 -- the new component's size still might be statically determinable
13706 -- (if, for example it has a static constraint). In that case we want
13707 -- Layout_Type to recompute the component's size, so we reset its
13708 -- size and positional fields.
13710 if Frontend_Layout_On_Target
13711 and then not Known_Static_Esize (Old_Compon)
13713 Set_Esize (New_Compon, Uint_0);
13714 Init_Normalized_First_Bit (New_Compon);
13715 Init_Normalized_Position (New_Compon);
13716 Init_Normalized_Position_Max (New_Compon);
13719 -- We do not want this node marked as Comes_From_Source, since
13720 -- otherwise it would get first class status and a separate cross-
13721 -- reference line would be generated. Illegitimate children do not
13722 -- rate such recognition.
13724 Set_Comes_From_Source (New_Compon, False);
13726 -- But it is a real entity, and a birth certificate must be properly
13727 -- registered by entering it into the entity list.
13729 Enter_Name (New_Compon);
13732 end Create_Component;
13734 -----------------------
13735 -- Is_Variant_Record --
13736 -----------------------
13738 function Is_Variant_Record (T : Entity_Id) return Boolean is
13740 return Nkind (Parent (T)) = N_Full_Type_Declaration
13741 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13742 and then Present (Component_List (Type_Definition (Parent (T))))
13745 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13746 end Is_Variant_Record;
13748 -- Start of processing for Create_Constrained_Components
13751 pragma Assert (Subt /= Base_Type (Subt));
13752 pragma Assert (Typ = Base_Type (Typ));
13754 Set_First_Entity (Subt, Empty);
13755 Set_Last_Entity (Subt, Empty);
13757 -- Check whether constraint is fully static, in which case we can
13758 -- optimize the list of components.
13760 Discr_Val := First_Elmt (Constraints);
13761 while Present (Discr_Val) loop
13762 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13763 Is_Static := False;
13767 Next_Elmt (Discr_Val);
13770 Set_Has_Static_Discriminants (Subt, Is_Static);
13774 -- Inherit the discriminants of the parent type
13776 Add_Discriminants : declare
13782 Old_C := First_Discriminant (Typ);
13784 while Present (Old_C) loop
13785 Num_Disc := Num_Disc + 1;
13786 New_C := Create_Component (Old_C);
13787 Set_Is_Public (New_C, Is_Public (Subt));
13788 Next_Discriminant (Old_C);
13791 -- For an untagged derived subtype, the number of discriminants may
13792 -- be smaller than the number of inherited discriminants, because
13793 -- several of them may be renamed by a single new discriminant or
13794 -- constrained. In this case, add the hidden discriminants back into
13795 -- the subtype, because they need to be present if the optimizer of
13796 -- the GCC 4.x back-end decides to break apart assignments between
13797 -- objects using the parent view into member-wise assignments.
13801 if Is_Derived_Type (Typ)
13802 and then not Is_Tagged_Type (Typ)
13804 Old_C := First_Stored_Discriminant (Typ);
13806 while Present (Old_C) loop
13807 Num_Gird := Num_Gird + 1;
13808 Next_Stored_Discriminant (Old_C);
13812 if Num_Gird > Num_Disc then
13814 -- Find out multiple uses of new discriminants, and add hidden
13815 -- components for the extra renamed discriminants. We recognize
13816 -- multiple uses through the Corresponding_Discriminant of a
13817 -- new discriminant: if it constrains several old discriminants,
13818 -- this field points to the last one in the parent type. The
13819 -- stored discriminants of the derived type have the same name
13820 -- as those of the parent.
13824 New_Discr : Entity_Id;
13825 Old_Discr : Entity_Id;
13828 Constr := First_Elmt (Stored_Constraint (Typ));
13829 Old_Discr := First_Stored_Discriminant (Typ);
13830 while Present (Constr) loop
13831 if Is_Entity_Name (Node (Constr))
13832 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13834 New_Discr := Entity (Node (Constr));
13836 if Chars (Corresponding_Discriminant (New_Discr)) /=
13839 -- The new discriminant has been used to rename a
13840 -- subsequent old discriminant. Introduce a shadow
13841 -- component for the current old discriminant.
13843 New_C := Create_Component (Old_Discr);
13844 Set_Original_Record_Component (New_C, Old_Discr);
13848 -- The constraint has eliminated the old discriminant.
13849 -- Introduce a shadow component.
13851 New_C := Create_Component (Old_Discr);
13852 Set_Original_Record_Component (New_C, Old_Discr);
13855 Next_Elmt (Constr);
13856 Next_Stored_Discriminant (Old_Discr);
13860 end Add_Discriminants;
13863 and then Is_Variant_Record (Typ)
13865 Collect_Fixed_Components (Typ);
13867 Gather_Components (
13869 Component_List (Type_Definition (Parent (Typ))),
13870 Governed_By => Assoc_List,
13872 Report_Errors => Errors);
13873 pragma Assert (not Errors);
13875 Create_All_Components;
13877 -- If the subtype declaration is created for a tagged type derivation
13878 -- with constraints, we retrieve the record definition of the parent
13879 -- type to select the components of the proper variant.
13882 and then Is_Tagged_Type (Typ)
13883 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13885 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13886 and then Is_Variant_Record (Parent_Type)
13888 Collect_Fixed_Components (Typ);
13890 Gather_Components (
13892 Component_List (Type_Definition (Parent (Parent_Type))),
13893 Governed_By => Assoc_List,
13895 Report_Errors => Errors);
13896 pragma Assert (not Errors);
13898 -- If the tagged derivation has a type extension, collect all the
13899 -- new components therein.
13902 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13904 Old_C := First_Component (Typ);
13905 while Present (Old_C) loop
13906 if Original_Record_Component (Old_C) = Old_C
13907 and then Chars (Old_C) /= Name_uTag
13908 and then Chars (Old_C) /= Name_uParent
13910 Append_Elmt (Old_C, Comp_List);
13913 Next_Component (Old_C);
13917 Create_All_Components;
13920 -- If discriminants are not static, or if this is a multi-level type
13921 -- extension, we have to include all components of the parent type.
13923 Old_C := First_Component (Typ);
13924 while Present (Old_C) loop
13925 New_C := Create_Component (Old_C);
13929 Constrain_Component_Type
13930 (Old_C, Subt, Decl_Node, Typ, Constraints));
13931 Set_Is_Public (New_C, Is_Public (Subt));
13933 Next_Component (Old_C);
13938 end Create_Constrained_Components;
13940 ------------------------------------------
13941 -- Decimal_Fixed_Point_Type_Declaration --
13942 ------------------------------------------
13944 procedure Decimal_Fixed_Point_Type_Declaration
13948 Loc : constant Source_Ptr := Sloc (Def);
13949 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13950 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13951 Implicit_Base : Entity_Id;
13958 Check_SPARK_05_Restriction
13959 ("decimal fixed point type is not allowed", Def);
13960 Check_Restriction (No_Fixed_Point, Def);
13962 -- Create implicit base type
13965 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13966 Set_Etype (Implicit_Base, Implicit_Base);
13968 -- Analyze and process delta expression
13970 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13972 Check_Delta_Expression (Delta_Expr);
13973 Delta_Val := Expr_Value_R (Delta_Expr);
13975 -- Check delta is power of 10, and determine scale value from it
13981 Scale_Val := Uint_0;
13984 if Val < Ureal_1 then
13985 while Val < Ureal_1 loop
13986 Val := Val * Ureal_10;
13987 Scale_Val := Scale_Val + 1;
13990 if Scale_Val > 18 then
13991 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13992 Scale_Val := UI_From_Int (+18);
13996 while Val > Ureal_1 loop
13997 Val := Val / Ureal_10;
13998 Scale_Val := Scale_Val - 1;
14001 if Scale_Val < -18 then
14002 Error_Msg_N ("scale is less than minimum value of -18", Def);
14003 Scale_Val := UI_From_Int (-18);
14007 if Val /= Ureal_1 then
14008 Error_Msg_N ("delta expression must be a power of 10", Def);
14009 Delta_Val := Ureal_10 ** (-Scale_Val);
14013 -- Set delta, scale and small (small = delta for decimal type)
14015 Set_Delta_Value (Implicit_Base, Delta_Val);
14016 Set_Scale_Value (Implicit_Base, Scale_Val);
14017 Set_Small_Value (Implicit_Base, Delta_Val);
14019 -- Analyze and process digits expression
14021 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14022 Check_Digits_Expression (Digs_Expr);
14023 Digs_Val := Expr_Value (Digs_Expr);
14025 if Digs_Val > 18 then
14026 Digs_Val := UI_From_Int (+18);
14027 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14030 Set_Digits_Value (Implicit_Base, Digs_Val);
14031 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14033 -- Set range of base type from digits value for now. This will be
14034 -- expanded to represent the true underlying base range by Freeze.
14036 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14038 -- Note: We leave size as zero for now, size will be set at freeze
14039 -- time. We have to do this for ordinary fixed-point, because the size
14040 -- depends on the specified small, and we might as well do the same for
14041 -- decimal fixed-point.
14043 pragma Assert (Esize (Implicit_Base) = Uint_0);
14045 -- If there are bounds given in the declaration use them as the
14046 -- bounds of the first named subtype.
14048 if Present (Real_Range_Specification (Def)) then
14050 RRS : constant Node_Id := Real_Range_Specification (Def);
14051 Low : constant Node_Id := Low_Bound (RRS);
14052 High : constant Node_Id := High_Bound (RRS);
14057 Analyze_And_Resolve (Low, Any_Real);
14058 Analyze_And_Resolve (High, Any_Real);
14059 Check_Real_Bound (Low);
14060 Check_Real_Bound (High);
14061 Low_Val := Expr_Value_R (Low);
14062 High_Val := Expr_Value_R (High);
14064 if Low_Val < (-Bound_Val) then
14066 ("range low bound too small for digits value", Low);
14067 Low_Val := -Bound_Val;
14070 if High_Val > Bound_Val then
14072 ("range high bound too large for digits value", High);
14073 High_Val := Bound_Val;
14076 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14079 -- If no explicit range, use range that corresponds to given
14080 -- digits value. This will end up as the final range for the
14084 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14087 -- Complete entity for first subtype. The inheritance of the rep item
14088 -- chain ensures that SPARK-related pragmas are not clobbered when the
14089 -- decimal fixed point type acts as a full view of a private type.
14091 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14092 Set_Etype (T, Implicit_Base);
14093 Set_Size_Info (T, Implicit_Base);
14094 Inherit_Rep_Item_Chain (T, Implicit_Base);
14095 Set_Digits_Value (T, Digs_Val);
14096 Set_Delta_Value (T, Delta_Val);
14097 Set_Small_Value (T, Delta_Val);
14098 Set_Scale_Value (T, Scale_Val);
14099 Set_Is_Constrained (T);
14100 end Decimal_Fixed_Point_Type_Declaration;
14102 -----------------------------------
14103 -- Derive_Progenitor_Subprograms --
14104 -----------------------------------
14106 procedure Derive_Progenitor_Subprograms
14107 (Parent_Type : Entity_Id;
14108 Tagged_Type : Entity_Id)
14113 Iface_Elmt : Elmt_Id;
14114 Iface_Subp : Entity_Id;
14115 New_Subp : Entity_Id := Empty;
14116 Prim_Elmt : Elmt_Id;
14121 pragma Assert (Ada_Version >= Ada_2005
14122 and then Is_Record_Type (Tagged_Type)
14123 and then Is_Tagged_Type (Tagged_Type)
14124 and then Has_Interfaces (Tagged_Type));
14126 -- Step 1: Transfer to the full-view primitives associated with the
14127 -- partial-view that cover interface primitives. Conceptually this
14128 -- work should be done later by Process_Full_View; done here to
14129 -- simplify its implementation at later stages. It can be safely
14130 -- done here because interfaces must be visible in the partial and
14131 -- private view (RM 7.3(7.3/2)).
14133 -- Small optimization: This work is only required if the parent may
14134 -- have entities whose Alias attribute reference an interface primitive.
14135 -- Such a situation may occur if the parent is an abstract type and the
14136 -- primitive has not been yet overridden or if the parent is a generic
14137 -- formal type covering interfaces.
14139 -- If the tagged type is not abstract, it cannot have abstract
14140 -- primitives (the only entities in the list of primitives of
14141 -- non-abstract tagged types that can reference abstract primitives
14142 -- through its Alias attribute are the internal entities that have
14143 -- attribute Interface_Alias, and these entities are generated later
14144 -- by Add_Internal_Interface_Entities).
14146 if In_Private_Part (Current_Scope)
14147 and then (Is_Abstract_Type (Parent_Type)
14149 Is_Generic_Type (Parent_Type))
14151 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14152 while Present (Elmt) loop
14153 Subp := Node (Elmt);
14155 -- At this stage it is not possible to have entities in the list
14156 -- of primitives that have attribute Interface_Alias.
14158 pragma Assert (No (Interface_Alias (Subp)));
14160 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14162 if Is_Interface (Typ) then
14163 E := Find_Primitive_Covering_Interface
14164 (Tagged_Type => Tagged_Type,
14165 Iface_Prim => Subp);
14168 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14170 Replace_Elmt (Elmt, E);
14171 Remove_Homonym (Subp);
14179 -- Step 2: Add primitives of progenitors that are not implemented by
14180 -- parents of Tagged_Type.
14182 if Present (Interfaces (Base_Type (Tagged_Type))) then
14183 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14184 while Present (Iface_Elmt) loop
14185 Iface := Node (Iface_Elmt);
14187 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14188 while Present (Prim_Elmt) loop
14189 Iface_Subp := Node (Prim_Elmt);
14191 -- Exclude derivation of predefined primitives except those
14192 -- that come from source, or are inherited from one that comes
14193 -- from source. Required to catch declarations of equality
14194 -- operators of interfaces. For example:
14196 -- type Iface is interface;
14197 -- function "=" (Left, Right : Iface) return Boolean;
14199 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14200 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14202 E := Find_Primitive_Covering_Interface
14203 (Tagged_Type => Tagged_Type,
14204 Iface_Prim => Iface_Subp);
14206 -- If not found we derive a new primitive leaving its alias
14207 -- attribute referencing the interface primitive.
14211 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14213 -- Ada 2012 (AI05-0197): If the covering primitive's name
14214 -- differs from the name of the interface primitive then it
14215 -- is a private primitive inherited from a parent type. In
14216 -- such case, given that Tagged_Type covers the interface,
14217 -- the inherited private primitive becomes visible. For such
14218 -- purpose we add a new entity that renames the inherited
14219 -- private primitive.
14221 elsif Chars (E) /= Chars (Iface_Subp) then
14222 pragma Assert (Has_Suffix (E, 'P'));
14224 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14225 Set_Alias (New_Subp, E);
14226 Set_Is_Abstract_Subprogram (New_Subp,
14227 Is_Abstract_Subprogram (E));
14229 -- Propagate to the full view interface entities associated
14230 -- with the partial view.
14232 elsif In_Private_Part (Current_Scope)
14233 and then Present (Alias (E))
14234 and then Alias (E) = Iface_Subp
14236 List_Containing (Parent (E)) /=
14237 Private_Declarations
14239 (Unit_Declaration_Node (Current_Scope)))
14241 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14245 Next_Elmt (Prim_Elmt);
14248 Next_Elmt (Iface_Elmt);
14251 end Derive_Progenitor_Subprograms;
14253 -----------------------
14254 -- Derive_Subprogram --
14255 -----------------------
14257 procedure Derive_Subprogram
14258 (New_Subp : in out Entity_Id;
14259 Parent_Subp : Entity_Id;
14260 Derived_Type : Entity_Id;
14261 Parent_Type : Entity_Id;
14262 Actual_Subp : Entity_Id := Empty)
14264 Formal : Entity_Id;
14265 -- Formal parameter of parent primitive operation
14267 Formal_Of_Actual : Entity_Id;
14268 -- Formal parameter of actual operation, when the derivation is to
14269 -- create a renaming for a primitive operation of an actual in an
14272 New_Formal : Entity_Id;
14273 -- Formal of inherited operation
14275 Visible_Subp : Entity_Id := Parent_Subp;
14277 function Is_Private_Overriding return Boolean;
14278 -- If Subp is a private overriding of a visible operation, the inherited
14279 -- operation derives from the overridden op (even though its body is the
14280 -- overriding one) and the inherited operation is visible now. See
14281 -- sem_disp to see the full details of the handling of the overridden
14282 -- subprogram, which is removed from the list of primitive operations of
14283 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14284 -- and used to diagnose abstract operations that need overriding in the
14287 procedure Replace_Type (Id, New_Id : Entity_Id);
14288 -- When the type is an anonymous access type, create a new access type
14289 -- designating the derived type.
14291 procedure Set_Derived_Name;
14292 -- This procedure sets the appropriate Chars name for New_Subp. This
14293 -- is normally just a copy of the parent name. An exception arises for
14294 -- type support subprograms, where the name is changed to reflect the
14295 -- name of the derived type, e.g. if type foo is derived from type bar,
14296 -- then a procedure barDA is derived with a name fooDA.
14298 ---------------------------
14299 -- Is_Private_Overriding --
14300 ---------------------------
14302 function Is_Private_Overriding return Boolean is
14306 -- If the parent is not a dispatching operation there is no
14307 -- need to investigate overridings
14309 if not Is_Dispatching_Operation (Parent_Subp) then
14313 -- The visible operation that is overridden is a homonym of the
14314 -- parent subprogram. We scan the homonym chain to find the one
14315 -- whose alias is the subprogram we are deriving.
14317 Prev := Current_Entity (Parent_Subp);
14318 while Present (Prev) loop
14319 if Ekind (Prev) = Ekind (Parent_Subp)
14320 and then Alias (Prev) = Parent_Subp
14321 and then Scope (Parent_Subp) = Scope (Prev)
14322 and then not Is_Hidden (Prev)
14324 Visible_Subp := Prev;
14328 Prev := Homonym (Prev);
14332 end Is_Private_Overriding;
14338 procedure Replace_Type (Id, New_Id : Entity_Id) is
14339 Id_Type : constant Entity_Id := Etype (Id);
14340 Acc_Type : Entity_Id;
14341 Par : constant Node_Id := Parent (Derived_Type);
14344 -- When the type is an anonymous access type, create a new access
14345 -- type designating the derived type. This itype must be elaborated
14346 -- at the point of the derivation, not on subsequent calls that may
14347 -- be out of the proper scope for Gigi, so we insert a reference to
14348 -- it after the derivation.
14350 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14352 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14355 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14356 and then Present (Full_View (Desig_Typ))
14357 and then not Is_Private_Type (Parent_Type)
14359 Desig_Typ := Full_View (Desig_Typ);
14362 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14364 -- Ada 2005 (AI-251): Handle also derivations of abstract
14365 -- interface primitives.
14367 or else (Is_Interface (Desig_Typ)
14368 and then not Is_Class_Wide_Type (Desig_Typ))
14370 Acc_Type := New_Copy (Id_Type);
14371 Set_Etype (Acc_Type, Acc_Type);
14372 Set_Scope (Acc_Type, New_Subp);
14374 -- Set size of anonymous access type. If we have an access
14375 -- to an unconstrained array, this is a fat pointer, so it
14376 -- is sizes at twice addtress size.
14378 if Is_Array_Type (Desig_Typ)
14379 and then not Is_Constrained (Desig_Typ)
14381 Init_Size (Acc_Type, 2 * System_Address_Size);
14383 -- Other cases use a thin pointer
14386 Init_Size (Acc_Type, System_Address_Size);
14389 -- Set remaining characterstics of anonymous access type
14391 Init_Alignment (Acc_Type);
14392 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14394 Set_Etype (New_Id, Acc_Type);
14395 Set_Scope (New_Id, New_Subp);
14397 -- Create a reference to it
14399 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14402 Set_Etype (New_Id, Id_Type);
14406 -- In Ada2012, a formal may have an incomplete type but the type
14407 -- derivation that inherits the primitive follows the full view.
14409 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14411 (Ekind (Id_Type) = E_Record_Type_With_Private
14412 and then Present (Full_View (Id_Type))
14414 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14416 (Ada_Version >= Ada_2012
14417 and then Ekind (Id_Type) = E_Incomplete_Type
14418 and then Full_View (Id_Type) = Parent_Type)
14420 -- Constraint checks on formals are generated during expansion,
14421 -- based on the signature of the original subprogram. The bounds
14422 -- of the derived type are not relevant, and thus we can use
14423 -- the base type for the formals. However, the return type may be
14424 -- used in a context that requires that the proper static bounds
14425 -- be used (a case statement, for example) and for those cases
14426 -- we must use the derived type (first subtype), not its base.
14428 -- If the derived_type_definition has no constraints, we know that
14429 -- the derived type has the same constraints as the first subtype
14430 -- of the parent, and we can also use it rather than its base,
14431 -- which can lead to more efficient code.
14433 if Etype (Id) = Parent_Type then
14434 if Is_Scalar_Type (Parent_Type)
14436 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14438 Set_Etype (New_Id, Derived_Type);
14440 elsif Nkind (Par) = N_Full_Type_Declaration
14442 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14445 (Subtype_Indication (Type_Definition (Par)))
14447 Set_Etype (New_Id, Derived_Type);
14450 Set_Etype (New_Id, Base_Type (Derived_Type));
14454 Set_Etype (New_Id, Base_Type (Derived_Type));
14458 Set_Etype (New_Id, Etype (Id));
14462 ----------------------
14463 -- Set_Derived_Name --
14464 ----------------------
14466 procedure Set_Derived_Name is
14467 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14469 if Nm = TSS_Null then
14470 Set_Chars (New_Subp, Chars (Parent_Subp));
14472 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14474 end Set_Derived_Name;
14476 -- Start of processing for Derive_Subprogram
14479 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14480 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14481 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
14483 -- Check whether the inherited subprogram is a private operation that
14484 -- should be inherited but not yet made visible. Such subprograms can
14485 -- become visible at a later point (e.g., the private part of a public
14486 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14487 -- following predicate is true, then this is not such a private
14488 -- operation and the subprogram simply inherits the name of the parent
14489 -- subprogram. Note the special check for the names of controlled
14490 -- operations, which are currently exempted from being inherited with
14491 -- a hidden name because they must be findable for generation of
14492 -- implicit run-time calls.
14494 if not Is_Hidden (Parent_Subp)
14495 or else Is_Internal (Parent_Subp)
14496 or else Is_Private_Overriding
14497 or else Is_Internal_Name (Chars (Parent_Subp))
14498 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14504 -- An inherited dispatching equality will be overridden by an internally
14505 -- generated one, or by an explicit one, so preserve its name and thus
14506 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14507 -- private operation it may become invisible if the full view has
14508 -- progenitors, and the dispatch table will be malformed.
14509 -- We check that the type is limited to handle the anomalous declaration
14510 -- of Limited_Controlled, which is derived from a non-limited type, and
14511 -- which is handled specially elsewhere as well.
14513 elsif Chars (Parent_Subp) = Name_Op_Eq
14514 and then Is_Dispatching_Operation (Parent_Subp)
14515 and then Etype (Parent_Subp) = Standard_Boolean
14516 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14518 Etype (First_Formal (Parent_Subp)) =
14519 Etype (Next_Formal (First_Formal (Parent_Subp)))
14523 -- If parent is hidden, this can be a regular derivation if the
14524 -- parent is immediately visible in a non-instantiating context,
14525 -- or if we are in the private part of an instance. This test
14526 -- should still be refined ???
14528 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14529 -- operation as a non-visible operation in cases where the parent
14530 -- subprogram might not be visible now, but was visible within the
14531 -- original generic, so it would be wrong to make the inherited
14532 -- subprogram non-visible now. (Not clear if this test is fully
14533 -- correct; are there any cases where we should declare the inherited
14534 -- operation as not visible to avoid it being overridden, e.g., when
14535 -- the parent type is a generic actual with private primitives ???)
14537 -- (they should be treated the same as other private inherited
14538 -- subprograms, but it's not clear how to do this cleanly). ???
14540 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14541 and then Is_Immediately_Visible (Parent_Subp)
14542 and then not In_Instance)
14543 or else In_Instance_Not_Visible
14547 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14548 -- overrides an interface primitive because interface primitives
14549 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14551 elsif Ada_Version >= Ada_2005
14552 and then Is_Dispatching_Operation (Parent_Subp)
14553 and then Covers_Some_Interface (Parent_Subp)
14557 -- Otherwise, the type is inheriting a private operation, so enter
14558 -- it with a special name so it can't be overridden.
14561 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14564 Set_Parent (New_Subp, Parent (Derived_Type));
14566 if Present (Actual_Subp) then
14567 Replace_Type (Actual_Subp, New_Subp);
14569 Replace_Type (Parent_Subp, New_Subp);
14572 Conditional_Delay (New_Subp, Parent_Subp);
14574 -- If we are creating a renaming for a primitive operation of an
14575 -- actual of a generic derived type, we must examine the signature
14576 -- of the actual primitive, not that of the generic formal, which for
14577 -- example may be an interface. However the name and initial value
14578 -- of the inherited operation are those of the formal primitive.
14580 Formal := First_Formal (Parent_Subp);
14582 if Present (Actual_Subp) then
14583 Formal_Of_Actual := First_Formal (Actual_Subp);
14585 Formal_Of_Actual := Empty;
14588 while Present (Formal) loop
14589 New_Formal := New_Copy (Formal);
14591 -- Normally we do not go copying parents, but in the case of
14592 -- formals, we need to link up to the declaration (which is the
14593 -- parameter specification), and it is fine to link up to the
14594 -- original formal's parameter specification in this case.
14596 Set_Parent (New_Formal, Parent (Formal));
14597 Append_Entity (New_Formal, New_Subp);
14599 if Present (Formal_Of_Actual) then
14600 Replace_Type (Formal_Of_Actual, New_Formal);
14601 Next_Formal (Formal_Of_Actual);
14603 Replace_Type (Formal, New_Formal);
14606 Next_Formal (Formal);
14609 -- If this derivation corresponds to a tagged generic actual, then
14610 -- primitive operations rename those of the actual. Otherwise the
14611 -- primitive operations rename those of the parent type, If the parent
14612 -- renames an intrinsic operator, so does the new subprogram. We except
14613 -- concatenation, which is always properly typed, and does not get
14614 -- expanded as other intrinsic operations.
14616 if No (Actual_Subp) then
14617 if Is_Intrinsic_Subprogram (Parent_Subp) then
14618 Set_Is_Intrinsic_Subprogram (New_Subp);
14620 if Present (Alias (Parent_Subp))
14621 and then Chars (Parent_Subp) /= Name_Op_Concat
14623 Set_Alias (New_Subp, Alias (Parent_Subp));
14625 Set_Alias (New_Subp, Parent_Subp);
14629 Set_Alias (New_Subp, Parent_Subp);
14633 Set_Alias (New_Subp, Actual_Subp);
14636 -- Derived subprograms of a tagged type must inherit the convention
14637 -- of the parent subprogram (a requirement of AI-117). Derived
14638 -- subprograms of untagged types simply get convention Ada by default.
14640 -- If the derived type is a tagged generic formal type with unknown
14641 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14643 -- However, if the type is derived from a generic formal, the further
14644 -- inherited subprogram has the convention of the non-generic ancestor.
14645 -- Otherwise there would be no way to override the operation.
14646 -- (This is subject to forthcoming ARG discussions).
14648 if Is_Tagged_Type (Derived_Type) then
14649 if Is_Generic_Type (Derived_Type)
14650 and then Has_Unknown_Discriminants (Derived_Type)
14652 Set_Convention (New_Subp, Convention_Intrinsic);
14655 if Is_Generic_Type (Parent_Type)
14656 and then Has_Unknown_Discriminants (Parent_Type)
14658 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14660 Set_Convention (New_Subp, Convention (Parent_Subp));
14665 -- Predefined controlled operations retain their name even if the parent
14666 -- is hidden (see above), but they are not primitive operations if the
14667 -- ancestor is not visible, for example if the parent is a private
14668 -- extension completed with a controlled extension. Note that a full
14669 -- type that is controlled can break privacy: the flag Is_Controlled is
14670 -- set on both views of the type.
14672 if Is_Controlled (Parent_Type)
14673 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14676 and then Is_Hidden (Parent_Subp)
14677 and then not Is_Visibly_Controlled (Parent_Type)
14679 Set_Is_Hidden (New_Subp);
14682 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14683 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14685 if Ekind (Parent_Subp) = E_Procedure then
14686 Set_Is_Valued_Procedure
14687 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14689 Set_Has_Controlling_Result
14690 (New_Subp, Has_Controlling_Result (Parent_Subp));
14693 -- No_Return must be inherited properly. If this is overridden in the
14694 -- case of a dispatching operation, then a check is made in Sem_Disp
14695 -- that the overriding operation is also No_Return (no such check is
14696 -- required for the case of non-dispatching operation.
14698 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14700 -- A derived function with a controlling result is abstract. If the
14701 -- Derived_Type is a nonabstract formal generic derived type, then
14702 -- inherited operations are not abstract: the required check is done at
14703 -- instantiation time. If the derivation is for a generic actual, the
14704 -- function is not abstract unless the actual is.
14706 if Is_Generic_Type (Derived_Type)
14707 and then not Is_Abstract_Type (Derived_Type)
14711 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14712 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14714 -- A subprogram subject to pragma Extensions_Visible with value False
14715 -- requires overriding if the subprogram has at least one controlling
14716 -- OUT parameter (SPARK RM 6.1.7(6)).
14718 elsif Ada_Version >= Ada_2005
14719 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14720 or else (Is_Tagged_Type (Derived_Type)
14721 and then Etype (New_Subp) = Derived_Type
14722 and then not Is_Null_Extension (Derived_Type))
14723 or else (Is_Tagged_Type (Derived_Type)
14724 and then Ekind (Etype (New_Subp)) =
14725 E_Anonymous_Access_Type
14726 and then Designated_Type (Etype (New_Subp)) =
14728 and then not Is_Null_Extension (Derived_Type))
14729 or else (Comes_From_Source (Alias (New_Subp))
14730 and then Is_EVF_Procedure (Alias (New_Subp))))
14731 and then No (Actual_Subp)
14733 if not Is_Tagged_Type (Derived_Type)
14734 or else Is_Abstract_Type (Derived_Type)
14735 or else Is_Abstract_Subprogram (Alias (New_Subp))
14737 Set_Is_Abstract_Subprogram (New_Subp);
14739 Set_Requires_Overriding (New_Subp);
14742 elsif Ada_Version < Ada_2005
14743 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14744 or else (Is_Tagged_Type (Derived_Type)
14745 and then Etype (New_Subp) = Derived_Type
14746 and then No (Actual_Subp)))
14748 Set_Is_Abstract_Subprogram (New_Subp);
14750 -- AI05-0097 : an inherited operation that dispatches on result is
14751 -- abstract if the derived type is abstract, even if the parent type
14752 -- is concrete and the derived type is a null extension.
14754 elsif Has_Controlling_Result (Alias (New_Subp))
14755 and then Is_Abstract_Type (Etype (New_Subp))
14757 Set_Is_Abstract_Subprogram (New_Subp);
14759 -- Finally, if the parent type is abstract we must verify that all
14760 -- inherited operations are either non-abstract or overridden, or that
14761 -- the derived type itself is abstract (this check is performed at the
14762 -- end of a package declaration, in Check_Abstract_Overriding). A
14763 -- private overriding in the parent type will not be visible in the
14764 -- derivation if we are not in an inner package or in a child unit of
14765 -- the parent type, in which case the abstractness of the inherited
14766 -- operation is carried to the new subprogram.
14768 elsif Is_Abstract_Type (Parent_Type)
14769 and then not In_Open_Scopes (Scope (Parent_Type))
14770 and then Is_Private_Overriding
14771 and then Is_Abstract_Subprogram (Visible_Subp)
14773 if No (Actual_Subp) then
14774 Set_Alias (New_Subp, Visible_Subp);
14775 Set_Is_Abstract_Subprogram (New_Subp, True);
14778 -- If this is a derivation for an instance of a formal derived
14779 -- type, abstractness comes from the primitive operation of the
14780 -- actual, not from the operation inherited from the ancestor.
14782 Set_Is_Abstract_Subprogram
14783 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14787 New_Overloaded_Entity (New_Subp, Derived_Type);
14789 -- Check for case of a derived subprogram for the instantiation of a
14790 -- formal derived tagged type, if so mark the subprogram as dispatching
14791 -- and inherit the dispatching attributes of the actual subprogram. The
14792 -- derived subprogram is effectively renaming of the actual subprogram,
14793 -- so it needs to have the same attributes as the actual.
14795 if Present (Actual_Subp)
14796 and then Is_Dispatching_Operation (Actual_Subp)
14798 Set_Is_Dispatching_Operation (New_Subp);
14800 if Present (DTC_Entity (Actual_Subp)) then
14801 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14802 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
14806 -- Indicate that a derived subprogram does not require a body and that
14807 -- it does not require processing of default expressions.
14809 Set_Has_Completion (New_Subp);
14810 Set_Default_Expressions_Processed (New_Subp);
14812 if Ekind (New_Subp) = E_Function then
14813 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14815 end Derive_Subprogram;
14817 ------------------------
14818 -- Derive_Subprograms --
14819 ------------------------
14821 procedure Derive_Subprograms
14822 (Parent_Type : Entity_Id;
14823 Derived_Type : Entity_Id;
14824 Generic_Actual : Entity_Id := Empty)
14826 Op_List : constant Elist_Id :=
14827 Collect_Primitive_Operations (Parent_Type);
14829 function Check_Derived_Type return Boolean;
14830 -- Check that all the entities derived from Parent_Type are found in
14831 -- the list of primitives of Derived_Type exactly in the same order.
14833 procedure Derive_Interface_Subprogram
14834 (New_Subp : in out Entity_Id;
14836 Actual_Subp : Entity_Id);
14837 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14838 -- (which is an interface primitive). If Generic_Actual is present then
14839 -- Actual_Subp is the actual subprogram corresponding with the generic
14840 -- subprogram Subp.
14842 function Check_Derived_Type return Boolean is
14846 New_Subp : Entity_Id;
14851 -- Traverse list of entities in the current scope searching for
14852 -- an incomplete type whose full-view is derived type
14854 E := First_Entity (Scope (Derived_Type));
14855 while Present (E) and then E /= Derived_Type loop
14856 if Ekind (E) = E_Incomplete_Type
14857 and then Present (Full_View (E))
14858 and then Full_View (E) = Derived_Type
14860 -- Disable this test if Derived_Type completes an incomplete
14861 -- type because in such case more primitives can be added
14862 -- later to the list of primitives of Derived_Type by routine
14863 -- Process_Incomplete_Dependents
14868 E := Next_Entity (E);
14871 List := Collect_Primitive_Operations (Derived_Type);
14872 Elmt := First_Elmt (List);
14874 Op_Elmt := First_Elmt (Op_List);
14875 while Present (Op_Elmt) loop
14876 Subp := Node (Op_Elmt);
14877 New_Subp := Node (Elmt);
14879 -- At this early stage Derived_Type has no entities with attribute
14880 -- Interface_Alias. In addition, such primitives are always
14881 -- located at the end of the list of primitives of Parent_Type.
14882 -- Therefore, if found we can safely stop processing pending
14885 exit when Present (Interface_Alias (Subp));
14887 -- Handle hidden entities
14889 if not Is_Predefined_Dispatching_Operation (Subp)
14890 and then Is_Hidden (Subp)
14892 if Present (New_Subp)
14893 and then Primitive_Names_Match (Subp, New_Subp)
14899 if not Present (New_Subp)
14900 or else Ekind (Subp) /= Ekind (New_Subp)
14901 or else not Primitive_Names_Match (Subp, New_Subp)
14909 Next_Elmt (Op_Elmt);
14913 end Check_Derived_Type;
14915 ---------------------------------
14916 -- Derive_Interface_Subprogram --
14917 ---------------------------------
14919 procedure Derive_Interface_Subprogram
14920 (New_Subp : in out Entity_Id;
14922 Actual_Subp : Entity_Id)
14924 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14925 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14928 pragma Assert (Is_Interface (Iface_Type));
14931 (New_Subp => New_Subp,
14932 Parent_Subp => Iface_Subp,
14933 Derived_Type => Derived_Type,
14934 Parent_Type => Iface_Type,
14935 Actual_Subp => Actual_Subp);
14937 -- Given that this new interface entity corresponds with a primitive
14938 -- of the parent that was not overridden we must leave it associated
14939 -- with its parent primitive to ensure that it will share the same
14940 -- dispatch table slot when overridden.
14942 if No (Actual_Subp) then
14943 Set_Alias (New_Subp, Subp);
14945 -- For instantiations this is not needed since the previous call to
14946 -- Derive_Subprogram leaves the entity well decorated.
14949 pragma Assert (Alias (New_Subp) = Actual_Subp);
14952 end Derive_Interface_Subprogram;
14956 Alias_Subp : Entity_Id;
14957 Act_List : Elist_Id;
14958 Act_Elmt : Elmt_Id;
14959 Act_Subp : Entity_Id := Empty;
14961 Need_Search : Boolean := False;
14962 New_Subp : Entity_Id := Empty;
14963 Parent_Base : Entity_Id;
14966 -- Start of processing for Derive_Subprograms
14969 if Ekind (Parent_Type) = E_Record_Type_With_Private
14970 and then Has_Discriminants (Parent_Type)
14971 and then Present (Full_View (Parent_Type))
14973 Parent_Base := Full_View (Parent_Type);
14975 Parent_Base := Parent_Type;
14978 if Present (Generic_Actual) then
14979 Act_List := Collect_Primitive_Operations (Generic_Actual);
14980 Act_Elmt := First_Elmt (Act_List);
14982 Act_List := No_Elist;
14983 Act_Elmt := No_Elmt;
14986 -- Derive primitives inherited from the parent. Note that if the generic
14987 -- actual is present, this is not really a type derivation, it is a
14988 -- completion within an instance.
14990 -- Case 1: Derived_Type does not implement interfaces
14992 if not Is_Tagged_Type (Derived_Type)
14993 or else (not Has_Interfaces (Derived_Type)
14994 and then not (Present (Generic_Actual)
14995 and then Has_Interfaces (Generic_Actual)))
14997 Elmt := First_Elmt (Op_List);
14998 while Present (Elmt) loop
14999 Subp := Node (Elmt);
15001 -- Literals are derived earlier in the process of building the
15002 -- derived type, and are skipped here.
15004 if Ekind (Subp) = E_Enumeration_Literal then
15007 -- The actual is a direct descendant and the common primitive
15008 -- operations appear in the same order.
15010 -- If the generic parent type is present, the derived type is an
15011 -- instance of a formal derived type, and within the instance its
15012 -- operations are those of the actual. We derive from the formal
15013 -- type but make the inherited operations aliases of the
15014 -- corresponding operations of the actual.
15017 pragma Assert (No (Node (Act_Elmt))
15018 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15021 (Subp, Node (Act_Elmt),
15022 Skip_Controlling_Formals => True)));
15025 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15027 if Present (Act_Elmt) then
15028 Next_Elmt (Act_Elmt);
15035 -- Case 2: Derived_Type implements interfaces
15038 -- If the parent type has no predefined primitives we remove
15039 -- predefined primitives from the list of primitives of generic
15040 -- actual to simplify the complexity of this algorithm.
15042 if Present (Generic_Actual) then
15044 Has_Predefined_Primitives : Boolean := False;
15047 -- Check if the parent type has predefined primitives
15049 Elmt := First_Elmt (Op_List);
15050 while Present (Elmt) loop
15051 Subp := Node (Elmt);
15053 if Is_Predefined_Dispatching_Operation (Subp)
15054 and then not Comes_From_Source (Ultimate_Alias (Subp))
15056 Has_Predefined_Primitives := True;
15063 -- Remove predefined primitives of Generic_Actual. We must use
15064 -- an auxiliary list because in case of tagged types the value
15065 -- returned by Collect_Primitive_Operations is the value stored
15066 -- in its Primitive_Operations attribute (and we don't want to
15067 -- modify its current contents).
15069 if not Has_Predefined_Primitives then
15071 Aux_List : constant Elist_Id := New_Elmt_List;
15074 Elmt := First_Elmt (Act_List);
15075 while Present (Elmt) loop
15076 Subp := Node (Elmt);
15078 if not Is_Predefined_Dispatching_Operation (Subp)
15079 or else Comes_From_Source (Subp)
15081 Append_Elmt (Subp, Aux_List);
15087 Act_List := Aux_List;
15091 Act_Elmt := First_Elmt (Act_List);
15092 Act_Subp := Node (Act_Elmt);
15096 -- Stage 1: If the generic actual is not present we derive the
15097 -- primitives inherited from the parent type. If the generic parent
15098 -- type is present, the derived type is an instance of a formal
15099 -- derived type, and within the instance its operations are those of
15100 -- the actual. We derive from the formal type but make the inherited
15101 -- operations aliases of the corresponding operations of the actual.
15103 Elmt := First_Elmt (Op_List);
15104 while Present (Elmt) loop
15105 Subp := Node (Elmt);
15106 Alias_Subp := Ultimate_Alias (Subp);
15108 -- Do not derive internal entities of the parent that link
15109 -- interface primitives with their covering primitive. These
15110 -- entities will be added to this type when frozen.
15112 if Present (Interface_Alias (Subp)) then
15116 -- If the generic actual is present find the corresponding
15117 -- operation in the generic actual. If the parent type is a
15118 -- direct ancestor of the derived type then, even if it is an
15119 -- interface, the operations are inherited from the primary
15120 -- dispatch table and are in the proper order. If we detect here
15121 -- that primitives are not in the same order we traverse the list
15122 -- of primitive operations of the actual to find the one that
15123 -- implements the interface primitive.
15127 (Present (Generic_Actual)
15128 and then Present (Act_Subp)
15130 (Primitive_Names_Match (Subp, Act_Subp)
15132 Type_Conformant (Subp, Act_Subp,
15133 Skip_Controlling_Formals => True)))
15135 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15136 Use_Full_View => True));
15138 -- Remember that we need searching for all pending primitives
15140 Need_Search := True;
15142 -- Handle entities associated with interface primitives
15144 if Present (Alias_Subp)
15145 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15146 and then not Is_Predefined_Dispatching_Operation (Subp)
15148 -- Search for the primitive in the homonym chain
15151 Find_Primitive_Covering_Interface
15152 (Tagged_Type => Generic_Actual,
15153 Iface_Prim => Alias_Subp);
15155 -- Previous search may not locate primitives covering
15156 -- interfaces defined in generics units or instantiations.
15157 -- (it fails if the covering primitive has formals whose
15158 -- type is also defined in generics or instantiations).
15159 -- In such case we search in the list of primitives of the
15160 -- generic actual for the internal entity that links the
15161 -- interface primitive and the covering primitive.
15164 and then Is_Generic_Type (Parent_Type)
15166 -- This code has been designed to handle only generic
15167 -- formals that implement interfaces that are defined
15168 -- in a generic unit or instantiation. If this code is
15169 -- needed for other cases we must review it because
15170 -- (given that it relies on Original_Location to locate
15171 -- the primitive of Generic_Actual that covers the
15172 -- interface) it could leave linked through attribute
15173 -- Alias entities of unrelated instantiations).
15177 (Scope (Find_Dispatching_Type (Alias_Subp)))
15179 Instantiation_Depth
15180 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15183 Iface_Prim_Loc : constant Source_Ptr :=
15184 Original_Location (Sloc (Alias_Subp));
15191 First_Elmt (Primitive_Operations (Generic_Actual));
15193 Search : while Present (Elmt) loop
15194 Prim := Node (Elmt);
15196 if Present (Interface_Alias (Prim))
15197 and then Original_Location
15198 (Sloc (Interface_Alias (Prim))) =
15201 Act_Subp := Alias (Prim);
15210 pragma Assert (Present (Act_Subp)
15211 or else Is_Abstract_Type (Generic_Actual)
15212 or else Serious_Errors_Detected > 0);
15214 -- Handle predefined primitives plus the rest of user-defined
15218 Act_Elmt := First_Elmt (Act_List);
15219 while Present (Act_Elmt) loop
15220 Act_Subp := Node (Act_Elmt);
15222 exit when Primitive_Names_Match (Subp, Act_Subp)
15223 and then Type_Conformant
15225 Skip_Controlling_Formals => True)
15226 and then No (Interface_Alias (Act_Subp));
15228 Next_Elmt (Act_Elmt);
15231 if No (Act_Elmt) then
15237 -- Case 1: If the parent is a limited interface then it has the
15238 -- predefined primitives of synchronized interfaces. However, the
15239 -- actual type may be a non-limited type and hence it does not
15240 -- have such primitives.
15242 if Present (Generic_Actual)
15243 and then not Present (Act_Subp)
15244 and then Is_Limited_Interface (Parent_Base)
15245 and then Is_Predefined_Interface_Primitive (Subp)
15249 -- Case 2: Inherit entities associated with interfaces that were
15250 -- not covered by the parent type. We exclude here null interface
15251 -- primitives because they do not need special management.
15253 -- We also exclude interface operations that are renamings. If the
15254 -- subprogram is an explicit renaming of an interface primitive,
15255 -- it is a regular primitive operation, and the presence of its
15256 -- alias is not relevant: it has to be derived like any other
15259 elsif Present (Alias (Subp))
15260 and then Nkind (Unit_Declaration_Node (Subp)) /=
15261 N_Subprogram_Renaming_Declaration
15262 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15264 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15265 and then Null_Present (Parent (Alias_Subp)))
15267 -- If this is an abstract private type then we transfer the
15268 -- derivation of the interface primitive from the partial view
15269 -- to the full view. This is safe because all the interfaces
15270 -- must be visible in the partial view. Done to avoid adding
15271 -- a new interface derivation to the private part of the
15272 -- enclosing package; otherwise this new derivation would be
15273 -- decorated as hidden when the analysis of the enclosing
15274 -- package completes.
15276 if Is_Abstract_Type (Derived_Type)
15277 and then In_Private_Part (Current_Scope)
15278 and then Has_Private_Declaration (Derived_Type)
15281 Partial_View : Entity_Id;
15286 Partial_View := First_Entity (Current_Scope);
15288 exit when No (Partial_View)
15289 or else (Has_Private_Declaration (Partial_View)
15291 Full_View (Partial_View) = Derived_Type);
15293 Next_Entity (Partial_View);
15296 -- If the partial view was not found then the source code
15297 -- has errors and the derivation is not needed.
15299 if Present (Partial_View) then
15301 First_Elmt (Primitive_Operations (Partial_View));
15302 while Present (Elmt) loop
15303 Ent := Node (Elmt);
15305 if Present (Alias (Ent))
15306 and then Ultimate_Alias (Ent) = Alias (Subp)
15309 (Ent, Primitive_Operations (Derived_Type));
15316 -- If the interface primitive was not found in the
15317 -- partial view then this interface primitive was
15318 -- overridden. We add a derivation to activate in
15319 -- Derive_Progenitor_Subprograms the machinery to
15323 Derive_Interface_Subprogram
15324 (New_Subp => New_Subp,
15326 Actual_Subp => Act_Subp);
15331 Derive_Interface_Subprogram
15332 (New_Subp => New_Subp,
15334 Actual_Subp => Act_Subp);
15337 -- Case 3: Common derivation
15341 (New_Subp => New_Subp,
15342 Parent_Subp => Subp,
15343 Derived_Type => Derived_Type,
15344 Parent_Type => Parent_Base,
15345 Actual_Subp => Act_Subp);
15348 -- No need to update Act_Elm if we must search for the
15349 -- corresponding operation in the generic actual
15352 and then Present (Act_Elmt)
15354 Next_Elmt (Act_Elmt);
15355 Act_Subp := Node (Act_Elmt);
15362 -- Inherit additional operations from progenitors. If the derived
15363 -- type is a generic actual, there are not new primitive operations
15364 -- for the type because it has those of the actual, and therefore
15365 -- nothing needs to be done. The renamings generated above are not
15366 -- primitive operations, and their purpose is simply to make the
15367 -- proper operations visible within an instantiation.
15369 if No (Generic_Actual) then
15370 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15374 -- Final check: Direct descendants must have their primitives in the
15375 -- same order. We exclude from this test untagged types and instances
15376 -- of formal derived types. We skip this test if we have already
15377 -- reported serious errors in the sources.
15379 pragma Assert (not Is_Tagged_Type (Derived_Type)
15380 or else Present (Generic_Actual)
15381 or else Serious_Errors_Detected > 0
15382 or else Check_Derived_Type);
15383 end Derive_Subprograms;
15385 --------------------------------
15386 -- Derived_Standard_Character --
15387 --------------------------------
15389 procedure Derived_Standard_Character
15391 Parent_Type : Entity_Id;
15392 Derived_Type : Entity_Id)
15394 Loc : constant Source_Ptr := Sloc (N);
15395 Def : constant Node_Id := Type_Definition (N);
15396 Indic : constant Node_Id := Subtype_Indication (Def);
15397 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15398 Implicit_Base : constant Entity_Id :=
15400 (E_Enumeration_Type, N, Derived_Type, 'B');
15406 Discard_Node (Process_Subtype (Indic, N));
15408 Set_Etype (Implicit_Base, Parent_Base);
15409 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15410 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15412 Set_Is_Character_Type (Implicit_Base, True);
15413 Set_Has_Delayed_Freeze (Implicit_Base);
15415 -- The bounds of the implicit base are the bounds of the parent base.
15416 -- Note that their type is the parent base.
15418 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15419 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15421 Set_Scalar_Range (Implicit_Base,
15424 High_Bound => Hi));
15426 Conditional_Delay (Derived_Type, Parent_Type);
15428 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15429 Set_Etype (Derived_Type, Implicit_Base);
15430 Set_Size_Info (Derived_Type, Parent_Type);
15432 if Unknown_RM_Size (Derived_Type) then
15433 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15436 Set_Is_Character_Type (Derived_Type, True);
15438 if Nkind (Indic) /= N_Subtype_Indication then
15440 -- If no explicit constraint, the bounds are those
15441 -- of the parent type.
15443 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15444 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15445 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15448 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15450 -- Because the implicit base is used in the conversion of the bounds, we
15451 -- have to freeze it now. This is similar to what is done for numeric
15452 -- types, and it equally suspicious, but otherwise a non-static bound
15453 -- will have a reference to an unfrozen type, which is rejected by Gigi
15454 -- (???). This requires specific care for definition of stream
15455 -- attributes. For details, see comments at the end of
15456 -- Build_Derived_Numeric_Type.
15458 Freeze_Before (N, Implicit_Base);
15459 end Derived_Standard_Character;
15461 ------------------------------
15462 -- Derived_Type_Declaration --
15463 ------------------------------
15465 procedure Derived_Type_Declaration
15468 Is_Completion : Boolean)
15470 Parent_Type : Entity_Id;
15472 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15473 -- Check whether the parent type is a generic formal, or derives
15474 -- directly or indirectly from one.
15476 ------------------------
15477 -- Comes_From_Generic --
15478 ------------------------
15480 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15482 if Is_Generic_Type (Typ) then
15485 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15488 elsif Is_Private_Type (Typ)
15489 and then Present (Full_View (Typ))
15490 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15494 elsif Is_Generic_Actual_Type (Typ) then
15500 end Comes_From_Generic;
15504 Def : constant Node_Id := Type_Definition (N);
15505 Iface_Def : Node_Id;
15506 Indic : constant Node_Id := Subtype_Indication (Def);
15507 Extension : constant Node_Id := Record_Extension_Part (Def);
15508 Parent_Node : Node_Id;
15511 -- Start of processing for Derived_Type_Declaration
15514 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15516 -- Ada 2005 (AI-251): In case of interface derivation check that the
15517 -- parent is also an interface.
15519 if Interface_Present (Def) then
15520 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15522 if not Is_Interface (Parent_Type) then
15523 Diagnose_Interface (Indic, Parent_Type);
15526 Parent_Node := Parent (Base_Type (Parent_Type));
15527 Iface_Def := Type_Definition (Parent_Node);
15529 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15530 -- other limited interfaces.
15532 if Limited_Present (Def) then
15533 if Limited_Present (Iface_Def) then
15536 elsif Protected_Present (Iface_Def) then
15538 ("descendant of& must be declared"
15539 & " as a protected interface",
15542 elsif Synchronized_Present (Iface_Def) then
15544 ("descendant of& must be declared"
15545 & " as a synchronized interface",
15548 elsif Task_Present (Iface_Def) then
15550 ("descendant of& must be declared as a task interface",
15555 ("(Ada 2005) limited interface cannot "
15556 & "inherit from non-limited interface", Indic);
15559 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15560 -- from non-limited or limited interfaces.
15562 elsif not Protected_Present (Def)
15563 and then not Synchronized_Present (Def)
15564 and then not Task_Present (Def)
15566 if Limited_Present (Iface_Def) then
15569 elsif Protected_Present (Iface_Def) then
15571 ("descendant of& must be declared"
15572 & " as a protected interface",
15575 elsif Synchronized_Present (Iface_Def) then
15577 ("descendant of& must be declared"
15578 & " as a synchronized interface",
15581 elsif Task_Present (Iface_Def) then
15583 ("descendant of& must be declared as a task interface",
15592 if Is_Tagged_Type (Parent_Type)
15593 and then Is_Concurrent_Type (Parent_Type)
15594 and then not Is_Interface (Parent_Type)
15597 ("parent type of a record extension cannot be "
15598 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
15599 Set_Etype (T, Any_Type);
15603 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15606 if Is_Tagged_Type (Parent_Type)
15607 and then Is_Non_Empty_List (Interface_List (Def))
15614 Intf := First (Interface_List (Def));
15615 while Present (Intf) loop
15616 T := Find_Type_Of_Subtype_Indic (Intf);
15618 if not Is_Interface (T) then
15619 Diagnose_Interface (Intf, T);
15621 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15622 -- a limited type from having a nonlimited progenitor.
15624 elsif (Limited_Present (Def)
15625 or else (not Is_Interface (Parent_Type)
15626 and then Is_Limited_Type (Parent_Type)))
15627 and then not Is_Limited_Interface (T)
15630 ("progenitor interface& of limited type must be limited",
15639 if Parent_Type = Any_Type
15640 or else Etype (Parent_Type) = Any_Type
15641 or else (Is_Class_Wide_Type (Parent_Type)
15642 and then Etype (Parent_Type) = T)
15644 -- If Parent_Type is undefined or illegal, make new type into a
15645 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15646 -- errors. If this is a self-definition, emit error now.
15648 if T = Parent_Type or else T = Etype (Parent_Type) then
15649 Error_Msg_N ("type cannot be used in its own definition", Indic);
15652 Set_Ekind (T, Ekind (Parent_Type));
15653 Set_Etype (T, Any_Type);
15654 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15656 if Is_Tagged_Type (T)
15657 and then Is_Record_Type (T)
15659 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15665 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15666 -- an interface is special because the list of interfaces in the full
15667 -- view can be given in any order. For example:
15669 -- type A is interface;
15670 -- type B is interface and A;
15671 -- type D is new B with private;
15673 -- type D is new A and B with null record; -- 1 --
15675 -- In this case we perform the following transformation of -1-:
15677 -- type D is new B and A with null record;
15679 -- If the parent of the full-view covers the parent of the partial-view
15680 -- we have two possible cases:
15682 -- 1) They have the same parent
15683 -- 2) The parent of the full-view implements some further interfaces
15685 -- In both cases we do not need to perform the transformation. In the
15686 -- first case the source program is correct and the transformation is
15687 -- not needed; in the second case the source program does not fulfill
15688 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15691 -- This transformation not only simplifies the rest of the analysis of
15692 -- this type declaration but also simplifies the correct generation of
15693 -- the object layout to the expander.
15695 if In_Private_Part (Current_Scope)
15696 and then Is_Interface (Parent_Type)
15700 Partial_View : Entity_Id;
15701 Partial_View_Parent : Entity_Id;
15702 New_Iface : Node_Id;
15705 -- Look for the associated private type declaration
15707 Partial_View := First_Entity (Current_Scope);
15709 exit when No (Partial_View)
15710 or else (Has_Private_Declaration (Partial_View)
15711 and then Full_View (Partial_View) = T);
15713 Next_Entity (Partial_View);
15716 -- If the partial view was not found then the source code has
15717 -- errors and the transformation is not needed.
15719 if Present (Partial_View) then
15720 Partial_View_Parent := Etype (Partial_View);
15722 -- If the parent of the full-view covers the parent of the
15723 -- partial-view we have nothing else to do.
15725 if Interface_Present_In_Ancestor
15726 (Parent_Type, Partial_View_Parent)
15730 -- Traverse the list of interfaces of the full-view to look
15731 -- for the parent of the partial-view and perform the tree
15735 Iface := First (Interface_List (Def));
15736 while Present (Iface) loop
15737 if Etype (Iface) = Etype (Partial_View) then
15738 Rewrite (Subtype_Indication (Def),
15739 New_Copy (Subtype_Indication
15740 (Parent (Partial_View))));
15743 Make_Identifier (Sloc (N), Chars (Parent_Type));
15744 Append (New_Iface, Interface_List (Def));
15746 -- Analyze the transformed code
15748 Derived_Type_Declaration (T, N, Is_Completion);
15759 -- Only composite types other than array types are allowed to have
15762 if Present (Discriminant_Specifications (N)) then
15763 if (Is_Elementary_Type (Parent_Type)
15765 Is_Array_Type (Parent_Type))
15766 and then not Error_Posted (N)
15769 ("elementary or array type cannot have discriminants",
15770 Defining_Identifier (First (Discriminant_Specifications (N))));
15771 Set_Has_Discriminants (T, False);
15773 -- The type is allowed to have discriminants
15776 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15780 -- In Ada 83, a derived type defined in a package specification cannot
15781 -- be used for further derivation until the end of its visible part.
15782 -- Note that derivation in the private part of the package is allowed.
15784 if Ada_Version = Ada_83
15785 and then Is_Derived_Type (Parent_Type)
15786 and then In_Visible_Part (Scope (Parent_Type))
15788 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15790 ("(Ada 83): premature use of type for derivation", Indic);
15794 -- Check for early use of incomplete or private type
15796 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15797 Error_Msg_N ("premature derivation of incomplete type", Indic);
15800 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15801 and then not Comes_From_Generic (Parent_Type))
15802 or else Has_Private_Component (Parent_Type)
15804 -- The ancestor type of a formal type can be incomplete, in which
15805 -- case only the operations of the partial view are available in the
15806 -- generic. Subsequent checks may be required when the full view is
15807 -- analyzed to verify that a derivation from a tagged type has an
15810 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15813 elsif No (Underlying_Type (Parent_Type))
15814 or else Has_Private_Component (Parent_Type)
15817 ("premature derivation of derived or private type", Indic);
15819 -- Flag the type itself as being in error, this prevents some
15820 -- nasty problems with subsequent uses of the malformed type.
15822 Set_Error_Posted (T);
15824 -- Check that within the immediate scope of an untagged partial
15825 -- view it's illegal to derive from the partial view if the
15826 -- full view is tagged. (7.3(7))
15828 -- We verify that the Parent_Type is a partial view by checking
15829 -- that it is not a Full_Type_Declaration (i.e. a private type or
15830 -- private extension declaration), to distinguish a partial view
15831 -- from a derivation from a private type which also appears as
15832 -- E_Private_Type. If the parent base type is not declared in an
15833 -- enclosing scope there is no need to check.
15835 elsif Present (Full_View (Parent_Type))
15836 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15837 and then not Is_Tagged_Type (Parent_Type)
15838 and then Is_Tagged_Type (Full_View (Parent_Type))
15839 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15842 ("premature derivation from type with tagged full view",
15847 -- Check that form of derivation is appropriate
15849 Taggd := Is_Tagged_Type (Parent_Type);
15851 -- Perhaps the parent type should be changed to the class-wide type's
15852 -- specific type in this case to prevent cascading errors ???
15854 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15855 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15859 if Present (Extension) and then not Taggd then
15861 ("type derived from untagged type cannot have extension", Indic);
15863 elsif No (Extension) and then Taggd then
15865 -- If this declaration is within a private part (or body) of a
15866 -- generic instantiation then the derivation is allowed (the parent
15867 -- type can only appear tagged in this case if it's a generic actual
15868 -- type, since it would otherwise have been rejected in the analysis
15869 -- of the generic template).
15871 if not Is_Generic_Actual_Type (Parent_Type)
15872 or else In_Visible_Part (Scope (Parent_Type))
15874 if Is_Class_Wide_Type (Parent_Type) then
15876 ("parent type must not be a class-wide type", Indic);
15878 -- Use specific type to prevent cascaded errors.
15880 Parent_Type := Etype (Parent_Type);
15884 ("type derived from tagged type must have extension", Indic);
15889 -- AI-443: Synchronized formal derived types require a private
15890 -- extension. There is no point in checking the ancestor type or
15891 -- the progenitors since the construct is wrong to begin with.
15893 if Ada_Version >= Ada_2005
15894 and then Is_Generic_Type (T)
15895 and then Present (Original_Node (N))
15898 Decl : constant Node_Id := Original_Node (N);
15901 if Nkind (Decl) = N_Formal_Type_Declaration
15902 and then Nkind (Formal_Type_Definition (Decl)) =
15903 N_Formal_Derived_Type_Definition
15904 and then Synchronized_Present (Formal_Type_Definition (Decl))
15905 and then No (Extension)
15907 -- Avoid emitting a duplicate error message
15909 and then not Error_Posted (Indic)
15912 ("synchronized derived type must have extension", N);
15917 if Null_Exclusion_Present (Def)
15918 and then not Is_Access_Type (Parent_Type)
15920 Error_Msg_N ("null exclusion can only apply to an access type", N);
15923 -- Avoid deriving parent primitives of underlying record views
15925 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15926 Derive_Subps => not Is_Underlying_Record_View (T));
15928 -- AI-419: The parent type of an explicitly limited derived type must
15929 -- be a limited type or a limited interface.
15931 if Limited_Present (Def) then
15932 Set_Is_Limited_Record (T);
15934 if Is_Interface (T) then
15935 Set_Is_Limited_Interface (T);
15938 if not Is_Limited_Type (Parent_Type)
15940 (not Is_Interface (Parent_Type)
15941 or else not Is_Limited_Interface (Parent_Type))
15943 -- AI05-0096: a derivation in the private part of an instance is
15944 -- legal if the generic formal is untagged limited, and the actual
15947 if Is_Generic_Actual_Type (Parent_Type)
15948 and then In_Private_Part (Current_Scope)
15951 (Generic_Parent_Type (Parent (Parent_Type)))
15957 ("parent type& of limited type must be limited",
15963 -- In SPARK, there are no derived type definitions other than type
15964 -- extensions of tagged record types.
15966 if No (Extension) then
15967 Check_SPARK_05_Restriction
15968 ("derived type is not allowed", Original_Node (N));
15970 end Derived_Type_Declaration;
15972 ------------------------
15973 -- Diagnose_Interface --
15974 ------------------------
15976 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15978 if not Is_Interface (E)
15979 and then E /= Any_Type
15981 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15983 end Diagnose_Interface;
15985 ----------------------------------
15986 -- Enumeration_Type_Declaration --
15987 ----------------------------------
15989 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15996 -- Create identifier node representing lower bound
15998 B_Node := New_Node (N_Identifier, Sloc (Def));
15999 L := First (Literals (Def));
16000 Set_Chars (B_Node, Chars (L));
16001 Set_Entity (B_Node, L);
16002 Set_Etype (B_Node, T);
16003 Set_Is_Static_Expression (B_Node, True);
16005 R_Node := New_Node (N_Range, Sloc (Def));
16006 Set_Low_Bound (R_Node, B_Node);
16008 Set_Ekind (T, E_Enumeration_Type);
16009 Set_First_Literal (T, L);
16011 Set_Is_Constrained (T);
16015 -- Loop through literals of enumeration type setting pos and rep values
16016 -- except that if the Ekind is already set, then it means the literal
16017 -- was already constructed (case of a derived type declaration and we
16018 -- should not disturb the Pos and Rep values.
16020 while Present (L) loop
16021 if Ekind (L) /= E_Enumeration_Literal then
16022 Set_Ekind (L, E_Enumeration_Literal);
16023 Set_Enumeration_Pos (L, Ev);
16024 Set_Enumeration_Rep (L, Ev);
16025 Set_Is_Known_Valid (L, True);
16029 New_Overloaded_Entity (L);
16030 Generate_Definition (L);
16031 Set_Convention (L, Convention_Intrinsic);
16033 -- Case of character literal
16035 if Nkind (L) = N_Defining_Character_Literal then
16036 Set_Is_Character_Type (T, True);
16038 -- Check violation of No_Wide_Characters
16040 if Restriction_Check_Required (No_Wide_Characters) then
16041 Get_Name_String (Chars (L));
16043 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16044 Check_Restriction (No_Wide_Characters, L);
16053 -- Now create a node representing upper bound
16055 B_Node := New_Node (N_Identifier, Sloc (Def));
16056 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16057 Set_Entity (B_Node, Last (Literals (Def)));
16058 Set_Etype (B_Node, T);
16059 Set_Is_Static_Expression (B_Node, True);
16061 Set_High_Bound (R_Node, B_Node);
16063 -- Initialize various fields of the type. Some of this information
16064 -- may be overwritten later through rep.clauses.
16066 Set_Scalar_Range (T, R_Node);
16067 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16068 Set_Enum_Esize (T);
16069 Set_Enum_Pos_To_Rep (T, Empty);
16071 -- Set Discard_Names if configuration pragma set, or if there is
16072 -- a parameterless pragma in the current declarative region
16074 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16075 Set_Discard_Names (T);
16078 -- Process end label if there is one
16080 if Present (Def) then
16081 Process_End_Label (Def, 'e', T);
16083 end Enumeration_Type_Declaration;
16085 ---------------------------------
16086 -- Expand_To_Stored_Constraint --
16087 ---------------------------------
16089 function Expand_To_Stored_Constraint
16091 Constraint : Elist_Id) return Elist_Id
16093 Explicitly_Discriminated_Type : Entity_Id;
16094 Expansion : Elist_Id;
16095 Discriminant : Entity_Id;
16097 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16098 -- Find the nearest type that actually specifies discriminants
16100 ---------------------------------
16101 -- Type_With_Explicit_Discrims --
16102 ---------------------------------
16104 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16105 Typ : constant E := Base_Type (Id);
16108 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16109 if Present (Full_View (Typ)) then
16110 return Type_With_Explicit_Discrims (Full_View (Typ));
16114 if Has_Discriminants (Typ) then
16119 if Etype (Typ) = Typ then
16121 elsif Has_Discriminants (Typ) then
16124 return Type_With_Explicit_Discrims (Etype (Typ));
16127 end Type_With_Explicit_Discrims;
16129 -- Start of processing for Expand_To_Stored_Constraint
16132 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16136 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16138 if No (Explicitly_Discriminated_Type) then
16142 Expansion := New_Elmt_List;
16145 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16146 while Present (Discriminant) loop
16148 (Get_Discriminant_Value
16149 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16151 Next_Stored_Discriminant (Discriminant);
16155 end Expand_To_Stored_Constraint;
16157 ---------------------------
16158 -- Find_Hidden_Interface --
16159 ---------------------------
16161 function Find_Hidden_Interface
16163 Dest : Elist_Id) return Entity_Id
16166 Iface_Elmt : Elmt_Id;
16169 if Present (Src) and then Present (Dest) then
16170 Iface_Elmt := First_Elmt (Src);
16171 while Present (Iface_Elmt) loop
16172 Iface := Node (Iface_Elmt);
16174 if Is_Interface (Iface)
16175 and then not Contain_Interface (Iface, Dest)
16180 Next_Elmt (Iface_Elmt);
16185 end Find_Hidden_Interface;
16187 --------------------
16188 -- Find_Type_Name --
16189 --------------------
16191 function Find_Type_Name (N : Node_Id) return Entity_Id is
16192 Id : constant Entity_Id := Defining_Identifier (N);
16194 New_Id : Entity_Id;
16195 Prev_Par : Node_Id;
16197 procedure Check_Duplicate_Aspects;
16198 -- Check that aspects specified in a completion have not been specified
16199 -- already in the partial view. Type_Invariant and others can be
16200 -- specified on either view but never on both.
16202 procedure Tag_Mismatch;
16203 -- Diagnose a tagged partial view whose full view is untagged.
16204 -- We post the message on the full view, with a reference to
16205 -- the previous partial view. The partial view can be private
16206 -- or incomplete, and these are handled in a different manner,
16207 -- so we determine the position of the error message from the
16208 -- respective slocs of both.
16210 -----------------------------
16211 -- Check_Duplicate_Aspects --
16212 -----------------------------
16213 procedure Check_Duplicate_Aspects is
16214 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16215 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16216 F_Spec, P_Spec : Node_Id;
16219 if Present (Prev_Aspects) and then Present (Full_Aspects) then
16220 F_Spec := First (Full_Aspects);
16221 while Present (F_Spec) loop
16222 P_Spec := First (Prev_Aspects);
16223 while Present (P_Spec) loop
16225 Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
16228 ("aspect already specified in private declaration",
16240 end Check_Duplicate_Aspects;
16246 procedure Tag_Mismatch is
16248 if Sloc (Prev) < Sloc (Id) then
16249 if Ada_Version >= Ada_2012
16250 and then Nkind (N) = N_Private_Type_Declaration
16253 ("declaration of private } must be a tagged type ", Id, Prev);
16256 ("full declaration of } must be a tagged type ", Id, Prev);
16260 if Ada_Version >= Ada_2012
16261 and then Nkind (N) = N_Private_Type_Declaration
16264 ("declaration of private } must be a tagged type ", Prev, Id);
16267 ("full declaration of } must be a tagged type ", Prev, Id);
16272 -- Start of processing for Find_Type_Name
16275 -- Find incomplete declaration, if one was given
16277 Prev := Current_Entity_In_Scope (Id);
16279 -- New type declaration
16285 -- Previous declaration exists
16288 Prev_Par := Parent (Prev);
16290 -- Error if not incomplete/private case except if previous
16291 -- declaration is implicit, etc. Enter_Name will emit error if
16294 if not Is_Incomplete_Or_Private_Type (Prev) then
16298 -- Check invalid completion of private or incomplete type
16300 elsif not Nkind_In (N, N_Full_Type_Declaration,
16301 N_Task_Type_Declaration,
16302 N_Protected_Type_Declaration)
16304 (Ada_Version < Ada_2012
16305 or else not Is_Incomplete_Type (Prev)
16306 or else not Nkind_In (N, N_Private_Type_Declaration,
16307 N_Private_Extension_Declaration))
16309 -- Completion must be a full type declarations (RM 7.3(4))
16311 Error_Msg_Sloc := Sloc (Prev);
16312 Error_Msg_NE ("invalid completion of }", Id, Prev);
16314 -- Set scope of Id to avoid cascaded errors. Entity is never
16315 -- examined again, except when saving globals in generics.
16317 Set_Scope (Id, Current_Scope);
16320 -- If this is a repeated incomplete declaration, no further
16321 -- checks are possible.
16323 if Nkind (N) = N_Incomplete_Type_Declaration then
16327 -- Case of full declaration of incomplete type
16329 elsif Ekind (Prev) = E_Incomplete_Type
16330 and then (Ada_Version < Ada_2012
16331 or else No (Full_View (Prev))
16332 or else not Is_Private_Type (Full_View (Prev)))
16334 -- Indicate that the incomplete declaration has a matching full
16335 -- declaration. The defining occurrence of the incomplete
16336 -- declaration remains the visible one, and the procedure
16337 -- Get_Full_View dereferences it whenever the type is used.
16339 if Present (Full_View (Prev)) then
16340 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16343 Set_Full_View (Prev, Id);
16344 Append_Entity (Id, Current_Scope);
16345 Set_Is_Public (Id, Is_Public (Prev));
16346 Set_Is_Internal (Id);
16349 -- If the incomplete view is tagged, a class_wide type has been
16350 -- created already. Use it for the private type as well, in order
16351 -- to prevent multiple incompatible class-wide types that may be
16352 -- created for self-referential anonymous access components.
16354 if Is_Tagged_Type (Prev)
16355 and then Present (Class_Wide_Type (Prev))
16357 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16358 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16360 -- If the incomplete type is completed by a private declaration
16361 -- the class-wide type remains associated with the incomplete
16362 -- type, to prevent order-of-elaboration issues in gigi, else
16363 -- we associate the class-wide type with the known full view.
16365 if Nkind (N) /= N_Private_Type_Declaration then
16366 Set_Etype (Class_Wide_Type (Id), Id);
16370 -- Case of full declaration of private type
16373 -- If the private type was a completion of an incomplete type then
16374 -- update Prev to reference the private type
16376 if Ada_Version >= Ada_2012
16377 and then Ekind (Prev) = E_Incomplete_Type
16378 and then Present (Full_View (Prev))
16379 and then Is_Private_Type (Full_View (Prev))
16381 Prev := Full_View (Prev);
16382 Prev_Par := Parent (Prev);
16385 if Nkind (N) = N_Full_Type_Declaration
16387 (Type_Definition (N), N_Record_Definition,
16388 N_Derived_Type_Definition)
16389 and then Interface_Present (Type_Definition (N))
16392 ("completion of private type cannot be an interface", N);
16395 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16396 if Etype (Prev) /= Prev then
16398 -- Prev is a private subtype or a derived type, and needs
16401 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16404 elsif Ekind (Prev) = E_Private_Type
16405 and then Nkind_In (N, N_Task_Type_Declaration,
16406 N_Protected_Type_Declaration)
16409 ("completion of nonlimited type cannot be limited", N);
16411 elsif Ekind (Prev) = E_Record_Type_With_Private
16412 and then Nkind_In (N, N_Task_Type_Declaration,
16413 N_Protected_Type_Declaration)
16415 if not Is_Limited_Record (Prev) then
16417 ("completion of nonlimited type cannot be limited", N);
16419 elsif No (Interface_List (N)) then
16421 ("completion of tagged private type must be tagged",
16426 -- Ada 2005 (AI-251): Private extension declaration of a task
16427 -- type or a protected type. This case arises when covering
16428 -- interface types.
16430 elsif Nkind_In (N, N_Task_Type_Declaration,
16431 N_Protected_Type_Declaration)
16435 elsif Nkind (N) /= N_Full_Type_Declaration
16436 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16439 ("full view of private extension must be an extension", N);
16441 elsif not (Abstract_Present (Parent (Prev)))
16442 and then Abstract_Present (Type_Definition (N))
16445 ("full view of non-abstract extension cannot be abstract", N);
16448 if not In_Private_Part (Current_Scope) then
16450 ("declaration of full view must appear in private part", N);
16453 if Ada_Version >= Ada_2012 then
16454 Check_Duplicate_Aspects;
16457 Copy_And_Swap (Prev, Id);
16458 Set_Has_Private_Declaration (Prev);
16459 Set_Has_Private_Declaration (Id);
16461 -- Preserve aspect and iterator flags that may have been set on
16462 -- the partial view.
16464 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16465 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16467 -- If no error, propagate freeze_node from private to full view.
16468 -- It may have been generated for an early operational item.
16470 if Present (Freeze_Node (Id))
16471 and then Serious_Errors_Detected = 0
16472 and then No (Full_View (Id))
16474 Set_Freeze_Node (Prev, Freeze_Node (Id));
16475 Set_Freeze_Node (Id, Empty);
16476 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16479 Set_Full_View (Id, Prev);
16483 -- Verify that full declaration conforms to partial one
16485 if Is_Incomplete_Or_Private_Type (Prev)
16486 and then Present (Discriminant_Specifications (Prev_Par))
16488 if Present (Discriminant_Specifications (N)) then
16489 if Ekind (Prev) = E_Incomplete_Type then
16490 Check_Discriminant_Conformance (N, Prev, Prev);
16492 Check_Discriminant_Conformance (N, Prev, Id);
16497 ("missing discriminants in full type declaration", N);
16499 -- To avoid cascaded errors on subsequent use, share the
16500 -- discriminants of the partial view.
16502 Set_Discriminant_Specifications (N,
16503 Discriminant_Specifications (Prev_Par));
16507 -- A prior untagged partial view can have an associated class-wide
16508 -- type due to use of the class attribute, and in this case the full
16509 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16510 -- of incomplete tagged declarations, but we check for it.
16513 and then (Is_Tagged_Type (Prev)
16514 or else Present (Class_Wide_Type (Prev)))
16516 -- Ada 2012 (AI05-0162): A private type may be the completion of
16517 -- an incomplete type.
16519 if Ada_Version >= Ada_2012
16520 and then Is_Incomplete_Type (Prev)
16521 and then Nkind_In (N, N_Private_Type_Declaration,
16522 N_Private_Extension_Declaration)
16524 -- No need to check private extensions since they are tagged
16526 if Nkind (N) = N_Private_Type_Declaration
16527 and then not Tagged_Present (N)
16532 -- The full declaration is either a tagged type (including
16533 -- a synchronized type that implements interfaces) or a
16534 -- type extension, otherwise this is an error.
16536 elsif Nkind_In (N, N_Task_Type_Declaration,
16537 N_Protected_Type_Declaration)
16539 if No (Interface_List (N))
16540 and then not Error_Posted (N)
16545 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16547 -- Indicate that the previous declaration (tagged incomplete
16548 -- or private declaration) requires the same on the full one.
16550 if not Tagged_Present (Type_Definition (N)) then
16552 Set_Is_Tagged_Type (Id);
16555 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16556 if No (Record_Extension_Part (Type_Definition (N))) then
16558 ("full declaration of } must be a record extension",
16561 -- Set some attributes to produce a usable full view
16563 Set_Is_Tagged_Type (Id);
16572 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16573 and then Present (Premature_Use (Parent (Prev)))
16575 Error_Msg_Sloc := Sloc (N);
16577 ("\full declaration #", Premature_Use (Parent (Prev)));
16582 end Find_Type_Name;
16584 -------------------------
16585 -- Find_Type_Of_Object --
16586 -------------------------
16588 function Find_Type_Of_Object
16589 (Obj_Def : Node_Id;
16590 Related_Nod : Node_Id) return Entity_Id
16592 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16593 P : Node_Id := Parent (Obj_Def);
16598 -- If the parent is a component_definition node we climb to the
16599 -- component_declaration node
16601 if Nkind (P) = N_Component_Definition then
16605 -- Case of an anonymous array subtype
16607 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16608 N_Unconstrained_Array_Definition)
16611 Array_Type_Declaration (T, Obj_Def);
16613 -- Create an explicit subtype whenever possible
16615 elsif Nkind (P) /= N_Component_Declaration
16616 and then Def_Kind = N_Subtype_Indication
16618 -- Base name of subtype on object name, which will be unique in
16619 -- the current scope.
16621 -- If this is a duplicate declaration, return base type, to avoid
16622 -- generating duplicate anonymous types.
16624 if Error_Posted (P) then
16625 Analyze (Subtype_Mark (Obj_Def));
16626 return Entity (Subtype_Mark (Obj_Def));
16631 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16633 T := Make_Defining_Identifier (Sloc (P), Nam);
16635 Insert_Action (Obj_Def,
16636 Make_Subtype_Declaration (Sloc (P),
16637 Defining_Identifier => T,
16638 Subtype_Indication => Relocate_Node (Obj_Def)));
16640 -- This subtype may need freezing, and this will not be done
16641 -- automatically if the object declaration is not in declarative
16642 -- part. Since this is an object declaration, the type cannot always
16643 -- be frozen here. Deferred constants do not freeze their type
16644 -- (which often enough will be private).
16646 if Nkind (P) = N_Object_Declaration
16647 and then Constant_Present (P)
16648 and then No (Expression (P))
16652 -- Here we freeze the base type of object type to catch premature use
16653 -- of discriminated private type without a full view.
16656 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16659 -- Ada 2005 AI-406: the object definition in an object declaration
16660 -- can be an access definition.
16662 elsif Def_Kind = N_Access_Definition then
16663 T := Access_Definition (Related_Nod, Obj_Def);
16665 Set_Is_Local_Anonymous_Access
16667 V => (Ada_Version < Ada_2012)
16668 or else (Nkind (P) /= N_Object_Declaration)
16669 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16671 -- Otherwise, the object definition is just a subtype_mark
16674 T := Process_Subtype (Obj_Def, Related_Nod);
16676 -- If expansion is disabled an object definition that is an aggregate
16677 -- will not get expanded and may lead to scoping problems in the back
16678 -- end, if the object is referenced in an inner scope. In that case
16679 -- create an itype reference for the object definition now. This
16680 -- may be redundant in some cases, but harmless.
16683 and then Nkind (Related_Nod) = N_Object_Declaration
16686 Build_Itype_Reference (T, Related_Nod);
16691 end Find_Type_Of_Object;
16693 --------------------------------
16694 -- Find_Type_Of_Subtype_Indic --
16695 --------------------------------
16697 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16701 -- Case of subtype mark with a constraint
16703 if Nkind (S) = N_Subtype_Indication then
16704 Find_Type (Subtype_Mark (S));
16705 Typ := Entity (Subtype_Mark (S));
16708 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16711 ("incorrect constraint for this kind of type", Constraint (S));
16712 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16715 -- Otherwise we have a subtype mark without a constraint
16717 elsif Error_Posted (S) then
16718 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16726 -- Check No_Wide_Characters restriction
16728 Check_Wide_Character_Restriction (Typ, S);
16731 end Find_Type_Of_Subtype_Indic;
16733 -------------------------------------
16734 -- Floating_Point_Type_Declaration --
16735 -------------------------------------
16737 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16738 Digs : constant Node_Id := Digits_Expression (Def);
16739 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16741 Base_Typ : Entity_Id;
16742 Implicit_Base : Entity_Id;
16745 function Can_Derive_From (E : Entity_Id) return Boolean;
16746 -- Find if given digits value, and possibly a specified range, allows
16747 -- derivation from specified type
16749 function Find_Base_Type return Entity_Id;
16750 -- Find a predefined base type that Def can derive from, or generate
16751 -- an error and substitute Long_Long_Float if none exists.
16753 ---------------------
16754 -- Can_Derive_From --
16755 ---------------------
16757 function Can_Derive_From (E : Entity_Id) return Boolean is
16758 Spec : constant Entity_Id := Real_Range_Specification (Def);
16761 -- Check specified "digits" constraint
16763 if Digs_Val > Digits_Value (E) then
16767 -- Check for matching range, if specified
16769 if Present (Spec) then
16770 if Expr_Value_R (Type_Low_Bound (E)) >
16771 Expr_Value_R (Low_Bound (Spec))
16776 if Expr_Value_R (Type_High_Bound (E)) <
16777 Expr_Value_R (High_Bound (Spec))
16784 end Can_Derive_From;
16786 --------------------
16787 -- Find_Base_Type --
16788 --------------------
16790 function Find_Base_Type return Entity_Id is
16791 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16794 -- Iterate over the predefined types in order, returning the first
16795 -- one that Def can derive from.
16797 while Present (Choice) loop
16798 if Can_Derive_From (Node (Choice)) then
16799 return Node (Choice);
16802 Next_Elmt (Choice);
16805 -- If we can't derive from any existing type, use Long_Long_Float
16806 -- and give appropriate message explaining the problem.
16808 if Digs_Val > Max_Digs_Val then
16809 -- It might be the case that there is a type with the requested
16810 -- range, just not the combination of digits and range.
16813 ("no predefined type has requested range and precision",
16814 Real_Range_Specification (Def));
16818 ("range too large for any predefined type",
16819 Real_Range_Specification (Def));
16822 return Standard_Long_Long_Float;
16823 end Find_Base_Type;
16825 -- Start of processing for Floating_Point_Type_Declaration
16828 Check_Restriction (No_Floating_Point, Def);
16830 -- Create an implicit base type
16833 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16835 -- Analyze and verify digits value
16837 Analyze_And_Resolve (Digs, Any_Integer);
16838 Check_Digits_Expression (Digs);
16839 Digs_Val := Expr_Value (Digs);
16841 -- Process possible range spec and find correct type to derive from
16843 Process_Real_Range_Specification (Def);
16845 -- Check that requested number of digits is not too high.
16847 if Digs_Val > Max_Digs_Val then
16848 -- The check for Max_Base_Digits may be somewhat expensive, as it
16849 -- requires reading System, so only do it when necessary.
16852 Max_Base_Digits : constant Uint :=
16855 (Parent (RTE (RE_Max_Base_Digits))));
16858 if Digs_Val > Max_Base_Digits then
16859 Error_Msg_Uint_1 := Max_Base_Digits;
16860 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16862 elsif No (Real_Range_Specification (Def)) then
16863 Error_Msg_Uint_1 := Max_Digs_Val;
16864 Error_Msg_N ("types with more than ^ digits need range spec "
16865 & "(RM 3.5.7(6))", Digs);
16870 -- Find a suitable type to derive from or complain and use a substitute
16872 Base_Typ := Find_Base_Type;
16874 -- If there are bounds given in the declaration use them as the bounds
16875 -- of the type, otherwise use the bounds of the predefined base type
16876 -- that was chosen based on the Digits value.
16878 if Present (Real_Range_Specification (Def)) then
16879 Set_Scalar_Range (T, Real_Range_Specification (Def));
16880 Set_Is_Constrained (T);
16882 -- The bounds of this range must be converted to machine numbers
16883 -- in accordance with RM 4.9(38).
16885 Bound := Type_Low_Bound (T);
16887 if Nkind (Bound) = N_Real_Literal then
16889 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16890 Set_Is_Machine_Number (Bound);
16893 Bound := Type_High_Bound (T);
16895 if Nkind (Bound) = N_Real_Literal then
16897 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16898 Set_Is_Machine_Number (Bound);
16902 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16905 -- Complete definition of implicit base and declared first subtype. The
16906 -- inheritance of the rep item chain ensures that SPARK-related pragmas
16907 -- are not clobbered when the floating point type acts as a full view of
16910 Set_Etype (Implicit_Base, Base_Typ);
16911 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16912 Set_Size_Info (Implicit_Base, Base_Typ);
16913 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16914 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16915 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16916 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16918 Set_Ekind (T, E_Floating_Point_Subtype);
16919 Set_Etype (T, Implicit_Base);
16920 Set_Size_Info (T, Implicit_Base);
16921 Set_RM_Size (T, RM_Size (Implicit_Base));
16922 Inherit_Rep_Item_Chain (T, Implicit_Base);
16923 Set_Digits_Value (T, Digs_Val);
16924 end Floating_Point_Type_Declaration;
16926 ----------------------------
16927 -- Get_Discriminant_Value --
16928 ----------------------------
16930 -- This is the situation:
16932 -- There is a non-derived type
16934 -- type T0 (Dx, Dy, Dz...)
16936 -- There are zero or more levels of derivation, with each derivation
16937 -- either purely inheriting the discriminants, or defining its own.
16939 -- type Ti is new Ti-1
16941 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16943 -- subtype Ti is ...
16945 -- The subtype issue is avoided by the use of Original_Record_Component,
16946 -- and the fact that derived subtypes also derive the constraints.
16948 -- This chain leads back from
16950 -- Typ_For_Constraint
16952 -- Typ_For_Constraint has discriminants, and the value for each
16953 -- discriminant is given by its corresponding Elmt of Constraints.
16955 -- Discriminant is some discriminant in this hierarchy
16957 -- We need to return its value
16959 -- We do this by recursively searching each level, and looking for
16960 -- Discriminant. Once we get to the bottom, we start backing up
16961 -- returning the value for it which may in turn be a discriminant
16962 -- further up, so on the backup we continue the substitution.
16964 function Get_Discriminant_Value
16965 (Discriminant : Entity_Id;
16966 Typ_For_Constraint : Entity_Id;
16967 Constraint : Elist_Id) return Node_Id
16969 function Root_Corresponding_Discriminant
16970 (Discr : Entity_Id) return Entity_Id;
16971 -- Given a discriminant, traverse the chain of inherited discriminants
16972 -- and return the topmost discriminant.
16974 function Search_Derivation_Levels
16976 Discrim_Values : Elist_Id;
16977 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16978 -- This is the routine that performs the recursive search of levels
16979 -- as described above.
16981 -------------------------------------
16982 -- Root_Corresponding_Discriminant --
16983 -------------------------------------
16985 function Root_Corresponding_Discriminant
16986 (Discr : Entity_Id) return Entity_Id
16992 while Present (Corresponding_Discriminant (D)) loop
16993 D := Corresponding_Discriminant (D);
16997 end Root_Corresponding_Discriminant;
16999 ------------------------------
17000 -- Search_Derivation_Levels --
17001 ------------------------------
17003 function Search_Derivation_Levels
17005 Discrim_Values : Elist_Id;
17006 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17010 Result : Node_Or_Entity_Id;
17011 Result_Entity : Node_Id;
17014 -- If inappropriate type, return Error, this happens only in
17015 -- cascaded error situations, and we want to avoid a blow up.
17017 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17021 -- Look deeper if possible. Use Stored_Constraints only for
17022 -- untagged types. For tagged types use the given constraint.
17023 -- This asymmetry needs explanation???
17025 if not Stored_Discrim_Values
17026 and then Present (Stored_Constraint (Ti))
17027 and then not Is_Tagged_Type (Ti)
17030 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17033 Td : constant Entity_Id := Etype (Ti);
17037 Result := Discriminant;
17040 if Present (Stored_Constraint (Ti)) then
17042 Search_Derivation_Levels
17043 (Td, Stored_Constraint (Ti), True);
17046 Search_Derivation_Levels
17047 (Td, Discrim_Values, Stored_Discrim_Values);
17053 -- Extra underlying places to search, if not found above. For
17054 -- concurrent types, the relevant discriminant appears in the
17055 -- corresponding record. For a type derived from a private type
17056 -- without discriminant, the full view inherits the discriminants
17057 -- of the full view of the parent.
17059 if Result = Discriminant then
17060 if Is_Concurrent_Type (Ti)
17061 and then Present (Corresponding_Record_Type (Ti))
17064 Search_Derivation_Levels (
17065 Corresponding_Record_Type (Ti),
17067 Stored_Discrim_Values);
17069 elsif Is_Private_Type (Ti)
17070 and then not Has_Discriminants (Ti)
17071 and then Present (Full_View (Ti))
17072 and then Etype (Full_View (Ti)) /= Ti
17075 Search_Derivation_Levels (
17078 Stored_Discrim_Values);
17082 -- If Result is not a (reference to a) discriminant, return it,
17083 -- otherwise set Result_Entity to the discriminant.
17085 if Nkind (Result) = N_Defining_Identifier then
17086 pragma Assert (Result = Discriminant);
17087 Result_Entity := Result;
17090 if not Denotes_Discriminant (Result) then
17094 Result_Entity := Entity (Result);
17097 -- See if this level of derivation actually has discriminants
17098 -- because tagged derivations can add them, hence the lower
17099 -- levels need not have any.
17101 if not Has_Discriminants (Ti) then
17105 -- Scan Ti's discriminants for Result_Entity,
17106 -- and return its corresponding value, if any.
17108 Result_Entity := Original_Record_Component (Result_Entity);
17110 Assoc := First_Elmt (Discrim_Values);
17112 if Stored_Discrim_Values then
17113 Disc := First_Stored_Discriminant (Ti);
17115 Disc := First_Discriminant (Ti);
17118 while Present (Disc) loop
17119 pragma Assert (Present (Assoc));
17121 if Original_Record_Component (Disc) = Result_Entity then
17122 return Node (Assoc);
17127 if Stored_Discrim_Values then
17128 Next_Stored_Discriminant (Disc);
17130 Next_Discriminant (Disc);
17134 -- Could not find it
17137 end Search_Derivation_Levels;
17141 Result : Node_Or_Entity_Id;
17143 -- Start of processing for Get_Discriminant_Value
17146 -- ??? This routine is a gigantic mess and will be deleted. For the
17147 -- time being just test for the trivial case before calling recurse.
17149 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17155 D := First_Discriminant (Typ_For_Constraint);
17156 E := First_Elmt (Constraint);
17157 while Present (D) loop
17158 if Chars (D) = Chars (Discriminant) then
17162 Next_Discriminant (D);
17168 Result := Search_Derivation_Levels
17169 (Typ_For_Constraint, Constraint, False);
17171 -- ??? hack to disappear when this routine is gone
17173 if Nkind (Result) = N_Defining_Identifier then
17179 D := First_Discriminant (Typ_For_Constraint);
17180 E := First_Elmt (Constraint);
17181 while Present (D) loop
17182 if Root_Corresponding_Discriminant (D) = Discriminant then
17186 Next_Discriminant (D);
17192 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17194 end Get_Discriminant_Value;
17196 --------------------------
17197 -- Has_Range_Constraint --
17198 --------------------------
17200 function Has_Range_Constraint (N : Node_Id) return Boolean is
17201 C : constant Node_Id := Constraint (N);
17204 if Nkind (C) = N_Range_Constraint then
17207 elsif Nkind (C) = N_Digits_Constraint then
17209 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17210 or else Present (Range_Constraint (C));
17212 elsif Nkind (C) = N_Delta_Constraint then
17213 return Present (Range_Constraint (C));
17218 end Has_Range_Constraint;
17220 ------------------------
17221 -- Inherit_Components --
17222 ------------------------
17224 function Inherit_Components
17226 Parent_Base : Entity_Id;
17227 Derived_Base : Entity_Id;
17228 Is_Tagged : Boolean;
17229 Inherit_Discr : Boolean;
17230 Discs : Elist_Id) return Elist_Id
17232 Assoc_List : constant Elist_Id := New_Elmt_List;
17234 procedure Inherit_Component
17235 (Old_C : Entity_Id;
17236 Plain_Discrim : Boolean := False;
17237 Stored_Discrim : Boolean := False);
17238 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17239 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17240 -- True, Old_C is a stored discriminant. If they are both false then
17241 -- Old_C is a regular component.
17243 -----------------------
17244 -- Inherit_Component --
17245 -----------------------
17247 procedure Inherit_Component
17248 (Old_C : Entity_Id;
17249 Plain_Discrim : Boolean := False;
17250 Stored_Discrim : Boolean := False)
17252 procedure Set_Anonymous_Type (Id : Entity_Id);
17253 -- Id denotes the entity of an access discriminant or anonymous
17254 -- access component. Set the type of Id to either the same type of
17255 -- Old_C or create a new one depending on whether the parent and
17256 -- the child types are in the same scope.
17258 ------------------------
17259 -- Set_Anonymous_Type --
17260 ------------------------
17262 procedure Set_Anonymous_Type (Id : Entity_Id) is
17263 Old_Typ : constant Entity_Id := Etype (Old_C);
17266 if Scope (Parent_Base) = Scope (Derived_Base) then
17267 Set_Etype (Id, Old_Typ);
17269 -- The parent and the derived type are in two different scopes.
17270 -- Reuse the type of the original discriminant / component by
17271 -- copying it in order to preserve all attributes.
17275 Typ : constant Entity_Id := New_Copy (Old_Typ);
17278 Set_Etype (Id, Typ);
17280 -- Since we do not generate component declarations for
17281 -- inherited components, associate the itype with the
17284 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17285 Set_Scope (Typ, Derived_Base);
17288 end Set_Anonymous_Type;
17290 -- Local variables and constants
17292 New_C : constant Entity_Id := New_Copy (Old_C);
17294 Corr_Discrim : Entity_Id;
17295 Discrim : Entity_Id;
17297 -- Start of processing for Inherit_Component
17300 pragma Assert (not Is_Tagged or not Stored_Discrim);
17302 Set_Parent (New_C, Parent (Old_C));
17304 -- Regular discriminants and components must be inserted in the scope
17305 -- of the Derived_Base. Do it here.
17307 if not Stored_Discrim then
17308 Enter_Name (New_C);
17311 -- For tagged types the Original_Record_Component must point to
17312 -- whatever this field was pointing to in the parent type. This has
17313 -- already been achieved by the call to New_Copy above.
17315 if not Is_Tagged then
17316 Set_Original_Record_Component (New_C, New_C);
17319 -- Set the proper type of an access discriminant
17321 if Ekind (New_C) = E_Discriminant
17322 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17324 Set_Anonymous_Type (New_C);
17327 -- If we have inherited a component then see if its Etype contains
17328 -- references to Parent_Base discriminants. In this case, replace
17329 -- these references with the constraints given in Discs. We do not
17330 -- do this for the partial view of private types because this is
17331 -- not needed (only the components of the full view will be used
17332 -- for code generation) and cause problem. We also avoid this
17333 -- transformation in some error situations.
17335 if Ekind (New_C) = E_Component then
17337 -- Set the proper type of an anonymous access component
17339 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17340 Set_Anonymous_Type (New_C);
17342 elsif (Is_Private_Type (Derived_Base)
17343 and then not Is_Generic_Type (Derived_Base))
17344 or else (Is_Empty_Elmt_List (Discs)
17345 and then not Expander_Active)
17347 Set_Etype (New_C, Etype (Old_C));
17350 -- The current component introduces a circularity of the
17353 -- limited with Pack_2;
17354 -- package Pack_1 is
17355 -- type T_1 is tagged record
17356 -- Comp : access Pack_2.T_2;
17362 -- package Pack_2 is
17363 -- type T_2 is new Pack_1.T_1 with ...;
17368 Constrain_Component_Type
17369 (Old_C, Derived_Base, N, Parent_Base, Discs));
17373 -- In derived tagged types it is illegal to reference a non
17374 -- discriminant component in the parent type. To catch this, mark
17375 -- these components with an Ekind of E_Void. This will be reset in
17376 -- Record_Type_Definition after processing the record extension of
17377 -- the derived type.
17379 -- If the declaration is a private extension, there is no further
17380 -- record extension to process, and the components retain their
17381 -- current kind, because they are visible at this point.
17383 if Is_Tagged and then Ekind (New_C) = E_Component
17384 and then Nkind (N) /= N_Private_Extension_Declaration
17386 Set_Ekind (New_C, E_Void);
17389 if Plain_Discrim then
17390 Set_Corresponding_Discriminant (New_C, Old_C);
17391 Build_Discriminal (New_C);
17393 -- If we are explicitly inheriting a stored discriminant it will be
17394 -- completely hidden.
17396 elsif Stored_Discrim then
17397 Set_Corresponding_Discriminant (New_C, Empty);
17398 Set_Discriminal (New_C, Empty);
17399 Set_Is_Completely_Hidden (New_C);
17401 -- Set the Original_Record_Component of each discriminant in the
17402 -- derived base to point to the corresponding stored that we just
17405 Discrim := First_Discriminant (Derived_Base);
17406 while Present (Discrim) loop
17407 Corr_Discrim := Corresponding_Discriminant (Discrim);
17409 -- Corr_Discrim could be missing in an error situation
17411 if Present (Corr_Discrim)
17412 and then Original_Record_Component (Corr_Discrim) = Old_C
17414 Set_Original_Record_Component (Discrim, New_C);
17417 Next_Discriminant (Discrim);
17420 Append_Entity (New_C, Derived_Base);
17423 if not Is_Tagged then
17424 Append_Elmt (Old_C, Assoc_List);
17425 Append_Elmt (New_C, Assoc_List);
17427 end Inherit_Component;
17429 -- Variables local to Inherit_Component
17431 Loc : constant Source_Ptr := Sloc (N);
17433 Parent_Discrim : Entity_Id;
17434 Stored_Discrim : Entity_Id;
17436 Component : Entity_Id;
17438 -- Start of processing for Inherit_Components
17441 if not Is_Tagged then
17442 Append_Elmt (Parent_Base, Assoc_List);
17443 Append_Elmt (Derived_Base, Assoc_List);
17446 -- Inherit parent discriminants if needed
17448 if Inherit_Discr then
17449 Parent_Discrim := First_Discriminant (Parent_Base);
17450 while Present (Parent_Discrim) loop
17451 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17452 Next_Discriminant (Parent_Discrim);
17456 -- Create explicit stored discrims for untagged types when necessary
17458 if not Has_Unknown_Discriminants (Derived_Base)
17459 and then Has_Discriminants (Parent_Base)
17460 and then not Is_Tagged
17463 or else First_Discriminant (Parent_Base) /=
17464 First_Stored_Discriminant (Parent_Base))
17466 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17467 while Present (Stored_Discrim) loop
17468 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17469 Next_Stored_Discriminant (Stored_Discrim);
17473 -- See if we can apply the second transformation for derived types, as
17474 -- explained in point 6. in the comments above Build_Derived_Record_Type
17475 -- This is achieved by appending Derived_Base discriminants into Discs,
17476 -- which has the side effect of returning a non empty Discs list to the
17477 -- caller of Inherit_Components, which is what we want. This must be
17478 -- done for private derived types if there are explicit stored
17479 -- discriminants, to ensure that we can retrieve the values of the
17480 -- constraints provided in the ancestors.
17483 and then Is_Empty_Elmt_List (Discs)
17484 and then Present (First_Discriminant (Derived_Base))
17486 (not Is_Private_Type (Derived_Base)
17487 or else Is_Completely_Hidden
17488 (First_Stored_Discriminant (Derived_Base))
17489 or else Is_Generic_Type (Derived_Base))
17491 D := First_Discriminant (Derived_Base);
17492 while Present (D) loop
17493 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17494 Next_Discriminant (D);
17498 -- Finally, inherit non-discriminant components unless they are not
17499 -- visible because defined or inherited from the full view of the
17500 -- parent. Don't inherit the _parent field of the parent type.
17502 Component := First_Entity (Parent_Base);
17503 while Present (Component) loop
17505 -- Ada 2005 (AI-251): Do not inherit components associated with
17506 -- secondary tags of the parent.
17508 if Ekind (Component) = E_Component
17509 and then Present (Related_Type (Component))
17513 elsif Ekind (Component) /= E_Component
17514 or else Chars (Component) = Name_uParent
17518 -- If the derived type is within the parent type's declarative
17519 -- region, then the components can still be inherited even though
17520 -- they aren't visible at this point. This can occur for cases
17521 -- such as within public child units where the components must
17522 -- become visible upon entering the child unit's private part.
17524 elsif not Is_Visible_Component (Component)
17525 and then not In_Open_Scopes (Scope (Parent_Base))
17529 elsif Ekind_In (Derived_Base, E_Private_Type,
17530 E_Limited_Private_Type)
17535 Inherit_Component (Component);
17538 Next_Entity (Component);
17541 -- For tagged derived types, inherited discriminants cannot be used in
17542 -- component declarations of the record extension part. To achieve this
17543 -- we mark the inherited discriminants as not visible.
17545 if Is_Tagged and then Inherit_Discr then
17546 D := First_Discriminant (Derived_Base);
17547 while Present (D) loop
17548 Set_Is_Immediately_Visible (D, False);
17549 Next_Discriminant (D);
17554 end Inherit_Components;
17556 -----------------------------
17557 -- Inherit_Predicate_Flags --
17558 -----------------------------
17560 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17562 Set_Has_Predicates (Subt, Has_Predicates (Par));
17563 Set_Has_Static_Predicate_Aspect
17564 (Subt, Has_Static_Predicate_Aspect (Par));
17565 Set_Has_Dynamic_Predicate_Aspect
17566 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17567 end Inherit_Predicate_Flags;
17569 ----------------------
17570 -- Is_EVF_Procedure --
17571 ----------------------
17573 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17574 Formal : Entity_Id;
17577 -- Examine the formals of an Extensions_Visible False procedure looking
17578 -- for a controlling OUT parameter.
17580 if Ekind (Subp) = E_Procedure
17581 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17583 Formal := First_Formal (Subp);
17584 while Present (Formal) loop
17585 if Ekind (Formal) = E_Out_Parameter
17586 and then Is_Controlling_Formal (Formal)
17591 Next_Formal (Formal);
17596 end Is_EVF_Procedure;
17598 -----------------------
17599 -- Is_Null_Extension --
17600 -----------------------
17602 function Is_Null_Extension (T : Entity_Id) return Boolean is
17603 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17604 Comp_List : Node_Id;
17608 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17609 or else not Is_Tagged_Type (T)
17610 or else Nkind (Type_Definition (Type_Decl)) /=
17611 N_Derived_Type_Definition
17612 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17618 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17620 if Present (Discriminant_Specifications (Type_Decl)) then
17623 elsif Present (Comp_List)
17624 and then Is_Non_Empty_List (Component_Items (Comp_List))
17626 Comp := First (Component_Items (Comp_List));
17628 -- Only user-defined components are relevant. The component list
17629 -- may also contain a parent component and internal components
17630 -- corresponding to secondary tags, but these do not determine
17631 -- whether this is a null extension.
17633 while Present (Comp) loop
17634 if Comes_From_Source (Comp) then
17645 end Is_Null_Extension;
17647 ------------------------------
17648 -- Is_Valid_Constraint_Kind --
17649 ------------------------------
17651 function Is_Valid_Constraint_Kind
17652 (T_Kind : Type_Kind;
17653 Constraint_Kind : Node_Kind) return Boolean
17657 when Enumeration_Kind |
17659 return Constraint_Kind = N_Range_Constraint;
17661 when Decimal_Fixed_Point_Kind =>
17662 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17663 N_Range_Constraint);
17665 when Ordinary_Fixed_Point_Kind =>
17666 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17667 N_Range_Constraint);
17670 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17671 N_Range_Constraint);
17678 E_Incomplete_Type |
17681 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17684 return True; -- Error will be detected later
17686 end Is_Valid_Constraint_Kind;
17688 --------------------------
17689 -- Is_Visible_Component --
17690 --------------------------
17692 function Is_Visible_Component
17694 N : Node_Id := Empty) return Boolean
17696 Original_Comp : Entity_Id := Empty;
17697 Original_Scope : Entity_Id;
17698 Type_Scope : Entity_Id;
17700 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17701 -- Check whether parent type of inherited component is declared locally,
17702 -- possibly within a nested package or instance. The current scope is
17703 -- the derived record itself.
17705 -------------------
17706 -- Is_Local_Type --
17707 -------------------
17709 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17713 Scop := Scope (Typ);
17714 while Present (Scop)
17715 and then Scop /= Standard_Standard
17717 if Scop = Scope (Current_Scope) then
17721 Scop := Scope (Scop);
17727 -- Start of processing for Is_Visible_Component
17730 if Ekind_In (C, E_Component, E_Discriminant) then
17731 Original_Comp := Original_Record_Component (C);
17734 if No (Original_Comp) then
17736 -- Premature usage, or previous error
17741 Original_Scope := Scope (Original_Comp);
17742 Type_Scope := Scope (Base_Type (Scope (C)));
17745 -- This test only concerns tagged types
17747 if not Is_Tagged_Type (Original_Scope) then
17750 -- If it is _Parent or _Tag, there is no visibility issue
17752 elsif not Comes_From_Source (Original_Comp) then
17755 -- Discriminants are visible unless the (private) type has unknown
17756 -- discriminants. If the discriminant reference is inserted for a
17757 -- discriminant check on a full view it is also visible.
17759 elsif Ekind (Original_Comp) = E_Discriminant
17761 (not Has_Unknown_Discriminants (Original_Scope)
17762 or else (Present (N)
17763 and then Nkind (N) = N_Selected_Component
17764 and then Nkind (Prefix (N)) = N_Type_Conversion
17765 and then not Comes_From_Source (Prefix (N))))
17769 -- In the body of an instantiation, no need to check for the visibility
17772 elsif In_Instance_Body then
17775 -- If the component has been declared in an ancestor which is currently
17776 -- a private type, then it is not visible. The same applies if the
17777 -- component's containing type is not in an open scope and the original
17778 -- component's enclosing type is a visible full view of a private type
17779 -- (which can occur in cases where an attempt is being made to reference
17780 -- a component in a sibling package that is inherited from a visible
17781 -- component of a type in an ancestor package; the component in the
17782 -- sibling package should not be visible even though the component it
17783 -- inherited from is visible). This does not apply however in the case
17784 -- where the scope of the type is a private child unit, or when the
17785 -- parent comes from a local package in which the ancestor is currently
17786 -- visible. The latter suppression of visibility is needed for cases
17787 -- that are tested in B730006.
17789 elsif Is_Private_Type (Original_Scope)
17791 (not Is_Private_Descendant (Type_Scope)
17792 and then not In_Open_Scopes (Type_Scope)
17793 and then Has_Private_Declaration (Original_Scope))
17795 -- If the type derives from an entity in a formal package, there
17796 -- are no additional visible components.
17798 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17799 N_Formal_Package_Declaration
17803 -- if we are not in the private part of the current package, there
17804 -- are no additional visible components.
17806 elsif Ekind (Scope (Current_Scope)) = E_Package
17807 and then not In_Private_Part (Scope (Current_Scope))
17812 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17813 and then In_Open_Scopes (Scope (Original_Scope))
17814 and then Is_Local_Type (Type_Scope);
17817 -- There is another weird way in which a component may be invisible when
17818 -- the private and the full view are not derived from the same ancestor.
17819 -- Here is an example :
17821 -- type A1 is tagged record F1 : integer; end record;
17822 -- type A2 is new A1 with record F2 : integer; end record;
17823 -- type T is new A1 with private;
17825 -- type T is new A2 with null record;
17827 -- In this case, the full view of T inherits F1 and F2 but the private
17828 -- view inherits only F1
17832 Ancestor : Entity_Id := Scope (C);
17836 if Ancestor = Original_Scope then
17838 elsif Ancestor = Etype (Ancestor) then
17842 Ancestor := Etype (Ancestor);
17846 end Is_Visible_Component;
17848 --------------------------
17849 -- Make_Class_Wide_Type --
17850 --------------------------
17852 procedure Make_Class_Wide_Type (T : Entity_Id) is
17853 CW_Type : Entity_Id;
17855 Next_E : Entity_Id;
17858 if Present (Class_Wide_Type (T)) then
17860 -- The class-wide type is a partially decorated entity created for a
17861 -- unanalyzed tagged type referenced through a limited with clause.
17862 -- When the tagged type is analyzed, its class-wide type needs to be
17863 -- redecorated. Note that we reuse the entity created by Decorate_
17864 -- Tagged_Type in order to preserve all links.
17866 if Materialize_Entity (Class_Wide_Type (T)) then
17867 CW_Type := Class_Wide_Type (T);
17868 Set_Materialize_Entity (CW_Type, False);
17870 -- The class wide type can have been defined by the partial view, in
17871 -- which case everything is already done.
17877 -- Default case, we need to create a new class-wide type
17881 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17884 -- Inherit root type characteristics
17886 CW_Name := Chars (CW_Type);
17887 Next_E := Next_Entity (CW_Type);
17888 Copy_Node (T, CW_Type);
17889 Set_Comes_From_Source (CW_Type, False);
17890 Set_Chars (CW_Type, CW_Name);
17891 Set_Parent (CW_Type, Parent (T));
17892 Set_Next_Entity (CW_Type, Next_E);
17894 -- Ensure we have a new freeze node for the class-wide type. The partial
17895 -- view may have freeze action of its own, requiring a proper freeze
17896 -- node, and the same freeze node cannot be shared between the two
17899 Set_Has_Delayed_Freeze (CW_Type);
17900 Set_Freeze_Node (CW_Type, Empty);
17902 -- Customize the class-wide type: It has no prim. op., it cannot be
17903 -- abstract and its Etype points back to the specific root type.
17905 Set_Ekind (CW_Type, E_Class_Wide_Type);
17906 Set_Is_Tagged_Type (CW_Type, True);
17907 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17908 Set_Is_Abstract_Type (CW_Type, False);
17909 Set_Is_Constrained (CW_Type, False);
17910 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17911 Set_Default_SSO (CW_Type);
17913 if Ekind (T) = E_Class_Wide_Subtype then
17914 Set_Etype (CW_Type, Etype (Base_Type (T)));
17916 Set_Etype (CW_Type, T);
17919 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
17921 -- If this is the class_wide type of a constrained subtype, it does
17922 -- not have discriminants.
17924 Set_Has_Discriminants (CW_Type,
17925 Has_Discriminants (T) and then not Is_Constrained (T));
17927 Set_Has_Unknown_Discriminants (CW_Type, True);
17928 Set_Class_Wide_Type (T, CW_Type);
17929 Set_Equivalent_Type (CW_Type, Empty);
17931 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17933 Set_Class_Wide_Type (CW_Type, CW_Type);
17934 end Make_Class_Wide_Type;
17940 procedure Make_Index
17942 Related_Nod : Node_Id;
17943 Related_Id : Entity_Id := Empty;
17944 Suffix_Index : Nat := 1;
17945 In_Iter_Schm : Boolean := False)
17949 Def_Id : Entity_Id := Empty;
17950 Found : Boolean := False;
17953 -- For a discrete range used in a constrained array definition and
17954 -- defined by a range, an implicit conversion to the predefined type
17955 -- INTEGER is assumed if each bound is either a numeric literal, a named
17956 -- number, or an attribute, and the type of both bounds (prior to the
17957 -- implicit conversion) is the type universal_integer. Otherwise, both
17958 -- bounds must be of the same discrete type, other than universal
17959 -- integer; this type must be determinable independently of the
17960 -- context, but using the fact that the type must be discrete and that
17961 -- both bounds must have the same type.
17963 -- Character literals also have a universal type in the absence of
17964 -- of additional context, and are resolved to Standard_Character.
17966 if Nkind (N) = N_Range then
17968 -- The index is given by a range constraint. The bounds are known
17969 -- to be of a consistent type.
17971 if not Is_Overloaded (N) then
17974 -- For universal bounds, choose the specific predefined type
17976 if T = Universal_Integer then
17977 T := Standard_Integer;
17979 elsif T = Any_Character then
17980 Ambiguous_Character (Low_Bound (N));
17982 T := Standard_Character;
17985 -- The node may be overloaded because some user-defined operators
17986 -- are available, but if a universal interpretation exists it is
17987 -- also the selected one.
17989 elsif Universal_Interpretation (N) = Universal_Integer then
17990 T := Standard_Integer;
17996 Ind : Interp_Index;
18000 Get_First_Interp (N, Ind, It);
18001 while Present (It.Typ) loop
18002 if Is_Discrete_Type (It.Typ) then
18005 and then not Covers (It.Typ, T)
18006 and then not Covers (T, It.Typ)
18008 Error_Msg_N ("ambiguous bounds in discrete range", N);
18016 Get_Next_Interp (Ind, It);
18019 if T = Any_Type then
18020 Error_Msg_N ("discrete type required for range", N);
18021 Set_Etype (N, Any_Type);
18024 elsif T = Universal_Integer then
18025 T := Standard_Integer;
18030 if not Is_Discrete_Type (T) then
18031 Error_Msg_N ("discrete type required for range", N);
18032 Set_Etype (N, Any_Type);
18036 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18037 and then Attribute_Name (Low_Bound (N)) = Name_First
18038 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18039 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18040 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18042 -- The type of the index will be the type of the prefix, as long
18043 -- as the upper bound is 'Last of the same type.
18045 Def_Id := Entity (Prefix (Low_Bound (N)));
18047 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18048 or else Attribute_Name (High_Bound (N)) /= Name_Last
18049 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18050 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18057 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18059 elsif Nkind (N) = N_Subtype_Indication then
18061 -- The index is given by a subtype with a range constraint
18063 T := Base_Type (Entity (Subtype_Mark (N)));
18065 if not Is_Discrete_Type (T) then
18066 Error_Msg_N ("discrete type required for range", N);
18067 Set_Etype (N, Any_Type);
18071 R := Range_Expression (Constraint (N));
18074 Process_Range_Expr_In_Decl
18075 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18077 elsif Nkind (N) = N_Attribute_Reference then
18079 -- Catch beginner's error (use of attribute other than 'Range)
18081 if Attribute_Name (N) /= Name_Range then
18082 Error_Msg_N ("expect attribute ''Range", N);
18083 Set_Etype (N, Any_Type);
18087 -- If the node denotes the range of a type mark, that is also the
18088 -- resulting type, and we do not need to create an Itype for it.
18090 if Is_Entity_Name (Prefix (N))
18091 and then Comes_From_Source (N)
18092 and then Is_Type (Entity (Prefix (N)))
18093 and then Is_Discrete_Type (Entity (Prefix (N)))
18095 Def_Id := Entity (Prefix (N));
18098 Analyze_And_Resolve (N);
18102 -- If none of the above, must be a subtype. We convert this to a
18103 -- range attribute reference because in the case of declared first
18104 -- named subtypes, the types in the range reference can be different
18105 -- from the type of the entity. A range attribute normalizes the
18106 -- reference and obtains the correct types for the bounds.
18108 -- This transformation is in the nature of an expansion, is only
18109 -- done if expansion is active. In particular, it is not done on
18110 -- formal generic types, because we need to retain the name of the
18111 -- original index for instantiation purposes.
18114 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18115 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18116 Set_Etype (N, Any_Integer);
18120 -- The type mark may be that of an incomplete type. It is only
18121 -- now that we can get the full view, previous analysis does
18122 -- not look specifically for a type mark.
18124 Set_Entity (N, Get_Full_View (Entity (N)));
18125 Set_Etype (N, Entity (N));
18126 Def_Id := Entity (N);
18128 if not Is_Discrete_Type (Def_Id) then
18129 Error_Msg_N ("discrete type required for index", N);
18130 Set_Etype (N, Any_Type);
18135 if Expander_Active then
18137 Make_Attribute_Reference (Sloc (N),
18138 Attribute_Name => Name_Range,
18139 Prefix => Relocate_Node (N)));
18141 -- The original was a subtype mark that does not freeze. This
18142 -- means that the rewritten version must not freeze either.
18144 Set_Must_Not_Freeze (N);
18145 Set_Must_Not_Freeze (Prefix (N));
18146 Analyze_And_Resolve (N);
18150 -- If expander is inactive, type is legal, nothing else to construct
18157 if not Is_Discrete_Type (T) then
18158 Error_Msg_N ("discrete type required for range", N);
18159 Set_Etype (N, Any_Type);
18162 elsif T = Any_Type then
18163 Set_Etype (N, Any_Type);
18167 -- We will now create the appropriate Itype to describe the range, but
18168 -- first a check. If we originally had a subtype, then we just label
18169 -- the range with this subtype. Not only is there no need to construct
18170 -- a new subtype, but it is wrong to do so for two reasons:
18172 -- 1. A legality concern, if we have a subtype, it must not freeze,
18173 -- and the Itype would cause freezing incorrectly
18175 -- 2. An efficiency concern, if we created an Itype, it would not be
18176 -- recognized as the same type for the purposes of eliminating
18177 -- checks in some circumstances.
18179 -- We signal this case by setting the subtype entity in Def_Id
18181 if No (Def_Id) then
18183 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18184 Set_Etype (Def_Id, Base_Type (T));
18186 if Is_Signed_Integer_Type (T) then
18187 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18189 elsif Is_Modular_Integer_Type (T) then
18190 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18193 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18194 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18195 Set_First_Literal (Def_Id, First_Literal (T));
18198 Set_Size_Info (Def_Id, (T));
18199 Set_RM_Size (Def_Id, RM_Size (T));
18200 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18202 Set_Scalar_Range (Def_Id, R);
18203 Conditional_Delay (Def_Id, T);
18205 if Nkind (N) = N_Subtype_Indication then
18206 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18209 -- In the subtype indication case, if the immediate parent of the
18210 -- new subtype is non-static, then the subtype we create is non-
18211 -- static, even if its bounds are static.
18213 if Nkind (N) = N_Subtype_Indication
18214 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18216 Set_Is_Non_Static_Subtype (Def_Id);
18220 -- Final step is to label the index with this constructed type
18222 Set_Etype (N, Def_Id);
18225 ------------------------------
18226 -- Modular_Type_Declaration --
18227 ------------------------------
18229 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18230 Mod_Expr : constant Node_Id := Expression (Def);
18233 procedure Set_Modular_Size (Bits : Int);
18234 -- Sets RM_Size to Bits, and Esize to normal word size above this
18236 ----------------------
18237 -- Set_Modular_Size --
18238 ----------------------
18240 procedure Set_Modular_Size (Bits : Int) is
18242 Set_RM_Size (T, UI_From_Int (Bits));
18247 elsif Bits <= 16 then
18248 Init_Esize (T, 16);
18250 elsif Bits <= 32 then
18251 Init_Esize (T, 32);
18254 Init_Esize (T, System_Max_Binary_Modulus_Power);
18257 if not Non_Binary_Modulus (T)
18258 and then Esize (T) = RM_Size (T)
18260 Set_Is_Known_Valid (T);
18262 end Set_Modular_Size;
18264 -- Start of processing for Modular_Type_Declaration
18267 -- If the mod expression is (exactly) 2 * literal, where literal is
18268 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18270 if Warn_On_Suspicious_Modulus_Value
18271 and then Nkind (Mod_Expr) = N_Op_Multiply
18272 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18273 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18274 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18275 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18278 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18281 -- Proceed with analysis of mod expression
18283 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18285 Set_Ekind (T, E_Modular_Integer_Type);
18286 Init_Alignment (T);
18287 Set_Is_Constrained (T);
18289 if not Is_OK_Static_Expression (Mod_Expr) then
18290 Flag_Non_Static_Expr
18291 ("non-static expression used for modular type bound!", Mod_Expr);
18292 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18294 M_Val := Expr_Value (Mod_Expr);
18298 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18299 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18302 if M_Val > 2 ** Standard_Long_Integer_Size then
18303 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18306 Set_Modulus (T, M_Val);
18308 -- Create bounds for the modular type based on the modulus given in
18309 -- the type declaration and then analyze and resolve those bounds.
18311 Set_Scalar_Range (T,
18312 Make_Range (Sloc (Mod_Expr),
18313 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18314 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18316 -- Properly analyze the literals for the range. We do this manually
18317 -- because we can't go calling Resolve, since we are resolving these
18318 -- bounds with the type, and this type is certainly not complete yet.
18320 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18321 Set_Etype (High_Bound (Scalar_Range (T)), T);
18322 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18323 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18325 -- Loop through powers of two to find number of bits required
18327 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18331 if M_Val = 2 ** Bits then
18332 Set_Modular_Size (Bits);
18337 elsif M_Val < 2 ** Bits then
18338 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18339 Set_Non_Binary_Modulus (T);
18341 if Bits > System_Max_Nonbinary_Modulus_Power then
18342 Error_Msg_Uint_1 :=
18343 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18345 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18346 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18350 -- In the non-binary case, set size as per RM 13.3(55)
18352 Set_Modular_Size (Bits);
18359 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18360 -- so we just signal an error and set the maximum size.
18362 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18363 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18365 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18366 Init_Alignment (T);
18368 end Modular_Type_Declaration;
18370 --------------------------
18371 -- New_Concatenation_Op --
18372 --------------------------
18374 procedure New_Concatenation_Op (Typ : Entity_Id) is
18375 Loc : constant Source_Ptr := Sloc (Typ);
18378 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18379 -- Create abbreviated declaration for the formal of a predefined
18380 -- Operator 'Op' of type 'Typ'
18382 --------------------
18383 -- Make_Op_Formal --
18384 --------------------
18386 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18387 Formal : Entity_Id;
18389 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18390 Set_Etype (Formal, Typ);
18391 Set_Mechanism (Formal, Default_Mechanism);
18393 end Make_Op_Formal;
18395 -- Start of processing for New_Concatenation_Op
18398 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18400 Set_Ekind (Op, E_Operator);
18401 Set_Scope (Op, Current_Scope);
18402 Set_Etype (Op, Typ);
18403 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18404 Set_Is_Immediately_Visible (Op);
18405 Set_Is_Intrinsic_Subprogram (Op);
18406 Set_Has_Completion (Op);
18407 Append_Entity (Op, Current_Scope);
18409 Set_Name_Entity_Id (Name_Op_Concat, Op);
18411 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18412 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18413 end New_Concatenation_Op;
18415 -------------------------
18416 -- OK_For_Limited_Init --
18417 -------------------------
18419 -- ???Check all calls of this, and compare the conditions under which it's
18422 function OK_For_Limited_Init
18424 Exp : Node_Id) return Boolean
18427 return Is_CPP_Constructor_Call (Exp)
18428 or else (Ada_Version >= Ada_2005
18429 and then not Debug_Flag_Dot_L
18430 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18431 end OK_For_Limited_Init;
18433 -------------------------------
18434 -- OK_For_Limited_Init_In_05 --
18435 -------------------------------
18437 function OK_For_Limited_Init_In_05
18439 Exp : Node_Id) return Boolean
18442 -- An object of a limited interface type can be initialized with any
18443 -- expression of a nonlimited descendant type.
18445 if Is_Class_Wide_Type (Typ)
18446 and then Is_Limited_Interface (Typ)
18447 and then not Is_Limited_Type (Etype (Exp))
18452 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18453 -- case of limited aggregates (including extension aggregates), and
18454 -- function calls. The function call may have been given in prefixed
18455 -- notation, in which case the original node is an indexed component.
18456 -- If the function is parameterless, the original node was an explicit
18457 -- dereference. The function may also be parameterless, in which case
18458 -- the source node is just an identifier.
18460 case Nkind (Original_Node (Exp)) is
18461 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18464 when N_Identifier =>
18465 return Present (Entity (Original_Node (Exp)))
18466 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18468 when N_Qualified_Expression =>
18470 OK_For_Limited_Init_In_05
18471 (Typ, Expression (Original_Node (Exp)));
18473 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18474 -- with a function call, the expander has rewritten the call into an
18475 -- N_Type_Conversion node to force displacement of the pointer to
18476 -- reference the component containing the secondary dispatch table.
18477 -- Otherwise a type conversion is not a legal context.
18478 -- A return statement for a build-in-place function returning a
18479 -- synchronized type also introduces an unchecked conversion.
18481 when N_Type_Conversion |
18482 N_Unchecked_Type_Conversion =>
18483 return not Comes_From_Source (Exp)
18485 OK_For_Limited_Init_In_05
18486 (Typ, Expression (Original_Node (Exp)));
18488 when N_Indexed_Component |
18489 N_Selected_Component |
18490 N_Explicit_Dereference =>
18491 return Nkind (Exp) = N_Function_Call;
18493 -- A use of 'Input is a function call, hence allowed. Normally the
18494 -- attribute will be changed to a call, but the attribute by itself
18495 -- can occur with -gnatc.
18497 when N_Attribute_Reference =>
18498 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18500 -- For a case expression, all dependent expressions must be legal
18502 when N_Case_Expression =>
18507 Alt := First (Alternatives (Original_Node (Exp)));
18508 while Present (Alt) loop
18509 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18519 -- For an if expression, all dependent expressions must be legal
18521 when N_If_Expression =>
18523 Then_Expr : constant Node_Id :=
18524 Next (First (Expressions (Original_Node (Exp))));
18525 Else_Expr : constant Node_Id := Next (Then_Expr);
18527 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18529 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18535 end OK_For_Limited_Init_In_05;
18537 -------------------------------------------
18538 -- Ordinary_Fixed_Point_Type_Declaration --
18539 -------------------------------------------
18541 procedure Ordinary_Fixed_Point_Type_Declaration
18545 Loc : constant Source_Ptr := Sloc (Def);
18546 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18547 RRS : constant Node_Id := Real_Range_Specification (Def);
18548 Implicit_Base : Entity_Id;
18555 Check_Restriction (No_Fixed_Point, Def);
18557 -- Create implicit base type
18560 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18561 Set_Etype (Implicit_Base, Implicit_Base);
18563 -- Analyze and process delta expression
18565 Analyze_And_Resolve (Delta_Expr, Any_Real);
18567 Check_Delta_Expression (Delta_Expr);
18568 Delta_Val := Expr_Value_R (Delta_Expr);
18570 Set_Delta_Value (Implicit_Base, Delta_Val);
18572 -- Compute default small from given delta, which is the largest power
18573 -- of two that does not exceed the given delta value.
18583 if Delta_Val < Ureal_1 then
18584 while Delta_Val < Tmp loop
18585 Tmp := Tmp / Ureal_2;
18586 Scale := Scale + 1;
18591 Tmp := Tmp * Ureal_2;
18592 exit when Tmp > Delta_Val;
18593 Scale := Scale - 1;
18597 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18600 Set_Small_Value (Implicit_Base, Small_Val);
18602 -- If no range was given, set a dummy range
18604 if RRS <= Empty_Or_Error then
18605 Low_Val := -Small_Val;
18606 High_Val := Small_Val;
18608 -- Otherwise analyze and process given range
18612 Low : constant Node_Id := Low_Bound (RRS);
18613 High : constant Node_Id := High_Bound (RRS);
18616 Analyze_And_Resolve (Low, Any_Real);
18617 Analyze_And_Resolve (High, Any_Real);
18618 Check_Real_Bound (Low);
18619 Check_Real_Bound (High);
18621 -- Obtain and set the range
18623 Low_Val := Expr_Value_R (Low);
18624 High_Val := Expr_Value_R (High);
18626 if Low_Val > High_Val then
18627 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18632 -- The range for both the implicit base and the declared first subtype
18633 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18634 -- set a temporary range in place. Note that the bounds of the base
18635 -- type will be widened to be symmetrical and to fill the available
18636 -- bits when the type is frozen.
18638 -- We could do this with all discrete types, and probably should, but
18639 -- we absolutely have to do it for fixed-point, since the end-points
18640 -- of the range and the size are determined by the small value, which
18641 -- could be reset before the freeze point.
18643 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18644 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18646 -- Complete definition of first subtype. The inheritance of the rep item
18647 -- chain ensures that SPARK-related pragmas are not clobbered when the
18648 -- ordinary fixed point type acts as a full view of a private type.
18650 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18651 Set_Etype (T, Implicit_Base);
18652 Init_Size_Align (T);
18653 Inherit_Rep_Item_Chain (T, Implicit_Base);
18654 Set_Small_Value (T, Small_Val);
18655 Set_Delta_Value (T, Delta_Val);
18656 Set_Is_Constrained (T);
18657 end Ordinary_Fixed_Point_Type_Declaration;
18659 ----------------------------------
18660 -- Preanalyze_Assert_Expression --
18661 ----------------------------------
18663 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18665 In_Assertion_Expr := In_Assertion_Expr + 1;
18666 Preanalyze_Spec_Expression (N, T);
18667 In_Assertion_Expr := In_Assertion_Expr - 1;
18668 end Preanalyze_Assert_Expression;
18670 -----------------------------------
18671 -- Preanalyze_Default_Expression --
18672 -----------------------------------
18674 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18675 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18677 In_Default_Expr := True;
18678 Preanalyze_Spec_Expression (N, T);
18679 In_Default_Expr := Save_In_Default_Expr;
18680 end Preanalyze_Default_Expression;
18682 --------------------------------
18683 -- Preanalyze_Spec_Expression --
18684 --------------------------------
18686 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18687 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18689 In_Spec_Expression := True;
18690 Preanalyze_And_Resolve (N, T);
18691 In_Spec_Expression := Save_In_Spec_Expression;
18692 end Preanalyze_Spec_Expression;
18694 ----------------------------------------
18695 -- Prepare_Private_Subtype_Completion --
18696 ----------------------------------------
18698 procedure Prepare_Private_Subtype_Completion
18700 Related_Nod : Node_Id)
18702 Id_B : constant Entity_Id := Base_Type (Id);
18703 Full_B : Entity_Id := Full_View (Id_B);
18707 if Present (Full_B) then
18709 -- Get to the underlying full view if necessary
18711 if Is_Private_Type (Full_B)
18712 and then Present (Underlying_Full_View (Full_B))
18714 Full_B := Underlying_Full_View (Full_B);
18717 -- The Base_Type is already completed, we can complete the subtype
18718 -- now. We have to create a new entity with the same name, Thus we
18719 -- can't use Create_Itype.
18721 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18722 Set_Is_Itype (Full);
18723 Set_Associated_Node_For_Itype (Full, Related_Nod);
18724 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18727 -- The parent subtype may be private, but the base might not, in some
18728 -- nested instances. In that case, the subtype does not need to be
18729 -- exchanged. It would still be nice to make private subtypes and their
18730 -- bases consistent at all times ???
18732 if Is_Private_Type (Id_B) then
18733 Append_Elmt (Id, Private_Dependents (Id_B));
18735 end Prepare_Private_Subtype_Completion;
18737 ---------------------------
18738 -- Process_Discriminants --
18739 ---------------------------
18741 procedure Process_Discriminants
18743 Prev : Entity_Id := Empty)
18745 Elist : constant Elist_Id := New_Elmt_List;
18748 Discr_Number : Uint;
18749 Discr_Type : Entity_Id;
18750 Default_Present : Boolean := False;
18751 Default_Not_Present : Boolean := False;
18754 -- A composite type other than an array type can have discriminants.
18755 -- On entry, the current scope is the composite type.
18757 -- The discriminants are initially entered into the scope of the type
18758 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18759 -- use, as explained at the end of this procedure.
18761 Discr := First (Discriminant_Specifications (N));
18762 while Present (Discr) loop
18763 Enter_Name (Defining_Identifier (Discr));
18765 -- For navigation purposes we add a reference to the discriminant
18766 -- in the entity for the type. If the current declaration is a
18767 -- completion, place references on the partial view. Otherwise the
18768 -- type is the current scope.
18770 if Present (Prev) then
18772 -- The references go on the partial view, if present. If the
18773 -- partial view has discriminants, the references have been
18774 -- generated already.
18776 if not Has_Discriminants (Prev) then
18777 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18781 (Current_Scope, Defining_Identifier (Discr), 'd');
18784 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18785 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18787 -- Ada 2005 (AI-254)
18789 if Present (Access_To_Subprogram_Definition
18790 (Discriminant_Type (Discr)))
18791 and then Protected_Present (Access_To_Subprogram_Definition
18792 (Discriminant_Type (Discr)))
18795 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18799 Find_Type (Discriminant_Type (Discr));
18800 Discr_Type := Etype (Discriminant_Type (Discr));
18802 if Error_Posted (Discriminant_Type (Discr)) then
18803 Discr_Type := Any_Type;
18807 -- Handling of discriminants that are access types
18809 if Is_Access_Type (Discr_Type) then
18811 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18812 -- limited record types
18814 if Ada_Version < Ada_2005 then
18815 Check_Access_Discriminant_Requires_Limited
18816 (Discr, Discriminant_Type (Discr));
18819 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
18821 ("(Ada 83) access discriminant not allowed", Discr);
18824 -- If not access type, must be a discrete type
18826 elsif not Is_Discrete_Type (Discr_Type) then
18828 ("discriminants must have a discrete or access type",
18829 Discriminant_Type (Discr));
18832 Set_Etype (Defining_Identifier (Discr), Discr_Type);
18834 -- If a discriminant specification includes the assignment compound
18835 -- delimiter followed by an expression, the expression is the default
18836 -- expression of the discriminant; the default expression must be of
18837 -- the type of the discriminant. (RM 3.7.1) Since this expression is
18838 -- a default expression, we do the special preanalysis, since this
18839 -- expression does not freeze (see section "Handling of Default and
18840 -- Per-Object Expressions" in spec of package Sem).
18842 if Present (Expression (Discr)) then
18843 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18847 if Nkind (N) = N_Formal_Type_Declaration then
18849 ("discriminant defaults not allowed for formal type",
18850 Expression (Discr));
18852 -- Flag an error for a tagged type with defaulted discriminants,
18853 -- excluding limited tagged types when compiling for Ada 2012
18854 -- (see AI05-0214).
18856 elsif Is_Tagged_Type (Current_Scope)
18857 and then (not Is_Limited_Type (Current_Scope)
18858 or else Ada_Version < Ada_2012)
18859 and then Comes_From_Source (N)
18861 -- Note: see similar test in Check_Or_Process_Discriminants, to
18862 -- handle the (illegal) case of the completion of an untagged
18863 -- view with discriminants with defaults by a tagged full view.
18864 -- We skip the check if Discr does not come from source, to
18865 -- account for the case of an untagged derived type providing
18866 -- defaults for a renamed discriminant from a private untagged
18867 -- ancestor with a tagged full view (ACATS B460006).
18869 if Ada_Version >= Ada_2012 then
18871 ("discriminants of nonlimited tagged type cannot have"
18873 Expression (Discr));
18876 ("discriminants of tagged type cannot have defaults",
18877 Expression (Discr));
18881 Default_Present := True;
18882 Append_Elmt (Expression (Discr), Elist);
18884 -- Tag the defining identifiers for the discriminants with
18885 -- their corresponding default expressions from the tree.
18887 Set_Discriminant_Default_Value
18888 (Defining_Identifier (Discr), Expression (Discr));
18891 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
18892 -- gets set unless we can be sure that no range check is required.
18894 if (GNATprove_Mode or not Expander_Active)
18897 (Expression (Discr), Discr_Type, Assume_Valid => True)
18899 Set_Do_Range_Check (Expression (Discr));
18902 -- No default discriminant value given
18905 Default_Not_Present := True;
18908 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
18909 -- Discr_Type but with the null-exclusion attribute
18911 if Ada_Version >= Ada_2005 then
18913 -- Ada 2005 (AI-231): Static checks
18915 if Can_Never_Be_Null (Discr_Type) then
18916 Null_Exclusion_Static_Checks (Discr);
18918 elsif Is_Access_Type (Discr_Type)
18919 and then Null_Exclusion_Present (Discr)
18921 -- No need to check itypes because in their case this check
18922 -- was done at their point of creation
18924 and then not Is_Itype (Discr_Type)
18926 if Can_Never_Be_Null (Discr_Type) then
18928 ("`NOT NULL` not allowed (& already excludes null)",
18933 Set_Etype (Defining_Identifier (Discr),
18934 Create_Null_Excluding_Itype
18936 Related_Nod => Discr));
18938 -- Check for improper null exclusion if the type is otherwise
18939 -- legal for a discriminant.
18941 elsif Null_Exclusion_Present (Discr)
18942 and then Is_Discrete_Type (Discr_Type)
18945 ("null exclusion can only apply to an access type", Discr);
18948 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18949 -- can't have defaults. Synchronized types, or types that are
18950 -- explicitly limited are fine, but special tests apply to derived
18951 -- types in generics: in a generic body we have to assume the
18952 -- worst, and therefore defaults are not allowed if the parent is
18953 -- a generic formal private type (see ACATS B370001).
18955 if Is_Access_Type (Discr_Type) and then Default_Present then
18956 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18957 or else Is_Limited_Record (Current_Scope)
18958 or else Is_Concurrent_Type (Current_Scope)
18959 or else Is_Concurrent_Record_Type (Current_Scope)
18960 or else Ekind (Current_Scope) = E_Limited_Private_Type
18962 if not Is_Derived_Type (Current_Scope)
18963 or else not Is_Generic_Type (Etype (Current_Scope))
18964 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18965 or else Limited_Present
18966 (Type_Definition (Parent (Current_Scope)))
18971 Error_Msg_N ("access discriminants of nonlimited types",
18972 Expression (Discr));
18973 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18976 elsif Present (Expression (Discr)) then
18978 ("(Ada 2005) access discriminants of nonlimited types",
18979 Expression (Discr));
18980 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18985 -- A discriminant cannot be effectively volatile. This check is only
18986 -- relevant when SPARK_Mode is on as it is not standard Ada legality
18987 -- rule (SPARK RM 7.1.3(6)).
18990 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
18992 Error_Msg_N ("discriminant cannot be volatile", Discr);
18998 -- An element list consisting of the default expressions of the
18999 -- discriminants is constructed in the above loop and used to set
19000 -- the Discriminant_Constraint attribute for the type. If an object
19001 -- is declared of this (record or task) type without any explicit
19002 -- discriminant constraint given, this element list will form the
19003 -- actual parameters for the corresponding initialization procedure
19006 Set_Discriminant_Constraint (Current_Scope, Elist);
19007 Set_Stored_Constraint (Current_Scope, No_Elist);
19009 -- Default expressions must be provided either for all or for none
19010 -- of the discriminants of a discriminant part. (RM 3.7.1)
19012 if Default_Present and then Default_Not_Present then
19014 ("incomplete specification of defaults for discriminants", N);
19017 -- The use of the name of a discriminant is not allowed in default
19018 -- expressions of a discriminant part if the specification of the
19019 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19021 -- To detect this, the discriminant names are entered initially with an
19022 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19023 -- attempt to use a void entity (for example in an expression that is
19024 -- type-checked) produces the error message: premature usage. Now after
19025 -- completing the semantic analysis of the discriminant part, we can set
19026 -- the Ekind of all the discriminants appropriately.
19028 Discr := First (Discriminant_Specifications (N));
19029 Discr_Number := Uint_1;
19030 while Present (Discr) loop
19031 Id := Defining_Identifier (Discr);
19032 Set_Ekind (Id, E_Discriminant);
19033 Init_Component_Location (Id);
19035 Set_Discriminant_Number (Id, Discr_Number);
19037 -- Make sure this is always set, even in illegal programs
19039 Set_Corresponding_Discriminant (Id, Empty);
19041 -- Initialize the Original_Record_Component to the entity itself.
19042 -- Inherit_Components will propagate the right value to
19043 -- discriminants in derived record types.
19045 Set_Original_Record_Component (Id, Id);
19047 -- Create the discriminal for the discriminant
19049 Build_Discriminal (Id);
19052 Discr_Number := Discr_Number + 1;
19055 Set_Has_Discriminants (Current_Scope);
19056 end Process_Discriminants;
19058 -----------------------
19059 -- Process_Full_View --
19060 -----------------------
19062 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19063 procedure Collect_Implemented_Interfaces
19065 Ifaces : Elist_Id);
19066 -- Ada 2005: Gather all the interfaces that Typ directly or
19067 -- inherently implements. Duplicate entries are not added to
19068 -- the list Ifaces.
19070 ------------------------------------
19071 -- Collect_Implemented_Interfaces --
19072 ------------------------------------
19074 procedure Collect_Implemented_Interfaces
19079 Iface_Elmt : Elmt_Id;
19082 -- Abstract interfaces are only associated with tagged record types
19084 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19088 -- Recursively climb to the ancestors
19090 if Etype (Typ) /= Typ
19092 -- Protect the frontend against wrong cyclic declarations like:
19094 -- type B is new A with private;
19095 -- type C is new A with private;
19097 -- type B is new C with null record;
19098 -- type C is new B with null record;
19100 and then Etype (Typ) /= Priv_T
19101 and then Etype (Typ) /= Full_T
19103 -- Keep separate the management of private type declarations
19105 if Ekind (Typ) = E_Record_Type_With_Private then
19107 -- Handle the following illegal usage:
19108 -- type Private_Type is tagged private;
19110 -- type Private_Type is new Type_Implementing_Iface;
19112 if Present (Full_View (Typ))
19113 and then Etype (Typ) /= Full_View (Typ)
19115 if Is_Interface (Etype (Typ)) then
19116 Append_Unique_Elmt (Etype (Typ), Ifaces);
19119 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19122 -- Non-private types
19125 if Is_Interface (Etype (Typ)) then
19126 Append_Unique_Elmt (Etype (Typ), Ifaces);
19129 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19133 -- Handle entities in the list of abstract interfaces
19135 if Present (Interfaces (Typ)) then
19136 Iface_Elmt := First_Elmt (Interfaces (Typ));
19137 while Present (Iface_Elmt) loop
19138 Iface := Node (Iface_Elmt);
19140 pragma Assert (Is_Interface (Iface));
19142 if not Contain_Interface (Iface, Ifaces) then
19143 Append_Elmt (Iface, Ifaces);
19144 Collect_Implemented_Interfaces (Iface, Ifaces);
19147 Next_Elmt (Iface_Elmt);
19150 end Collect_Implemented_Interfaces;
19154 Full_Indic : Node_Id;
19155 Full_Parent : Entity_Id;
19156 Priv_Parent : Entity_Id;
19158 -- Start of processing for Process_Full_View
19161 -- First some sanity checks that must be done after semantic
19162 -- decoration of the full view and thus cannot be placed with other
19163 -- similar checks in Find_Type_Name
19165 if not Is_Limited_Type (Priv_T)
19166 and then (Is_Limited_Type (Full_T)
19167 or else Is_Limited_Composite (Full_T))
19169 if In_Instance then
19173 ("completion of nonlimited type cannot be limited", Full_T);
19174 Explain_Limited_Type (Full_T, Full_T);
19177 elsif Is_Abstract_Type (Full_T)
19178 and then not Is_Abstract_Type (Priv_T)
19181 ("completion of nonabstract type cannot be abstract", Full_T);
19183 elsif Is_Tagged_Type (Priv_T)
19184 and then Is_Limited_Type (Priv_T)
19185 and then not Is_Limited_Type (Full_T)
19187 -- If pragma CPP_Class was applied to the private declaration
19188 -- propagate the limitedness to the full-view
19190 if Is_CPP_Class (Priv_T) then
19191 Set_Is_Limited_Record (Full_T);
19193 -- GNAT allow its own definition of Limited_Controlled to disobey
19194 -- this rule in order in ease the implementation. This test is safe
19195 -- because Root_Controlled is defined in a child of System that
19196 -- normal programs are not supposed to use.
19198 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19199 Set_Is_Limited_Composite (Full_T);
19202 ("completion of limited tagged type must be limited", Full_T);
19205 elsif Is_Generic_Type (Priv_T) then
19206 Error_Msg_N ("generic type cannot have a completion", Full_T);
19209 -- Check that ancestor interfaces of private and full views are
19210 -- consistent. We omit this check for synchronized types because
19211 -- they are performed on the corresponding record type when frozen.
19213 if Ada_Version >= Ada_2005
19214 and then Is_Tagged_Type (Priv_T)
19215 and then Is_Tagged_Type (Full_T)
19216 and then not Is_Concurrent_Type (Full_T)
19220 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19221 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19224 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19225 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19227 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19228 -- an interface type if and only if the full type is descendant
19229 -- of the interface type (AARM 7.3 (7.3/2)).
19231 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19233 if Present (Iface) then
19235 ("interface in partial view& not implemented by full type "
19236 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19239 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19241 if Present (Iface) then
19243 ("interface & not implemented by partial view "
19244 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19249 if Is_Tagged_Type (Priv_T)
19250 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19251 and then Is_Derived_Type (Full_T)
19253 Priv_Parent := Etype (Priv_T);
19255 -- The full view of a private extension may have been transformed
19256 -- into an unconstrained derived type declaration and a subtype
19257 -- declaration (see build_derived_record_type for details).
19259 if Nkind (N) = N_Subtype_Declaration then
19260 Full_Indic := Subtype_Indication (N);
19261 Full_Parent := Etype (Base_Type (Full_T));
19263 Full_Indic := Subtype_Indication (Type_Definition (N));
19264 Full_Parent := Etype (Full_T);
19267 -- Check that the parent type of the full type is a descendant of
19268 -- the ancestor subtype given in the private extension. If either
19269 -- entity has an Etype equal to Any_Type then we had some previous
19270 -- error situation [7.3(8)].
19272 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19275 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19276 -- any order. Therefore we don't have to check that its parent must
19277 -- be a descendant of the parent of the private type declaration.
19279 elsif Is_Interface (Priv_Parent)
19280 and then Is_Interface (Full_Parent)
19284 -- Ada 2005 (AI-251): If the parent of the private type declaration
19285 -- is an interface there is no need to check that it is an ancestor
19286 -- of the associated full type declaration. The required tests for
19287 -- this case are performed by Build_Derived_Record_Type.
19289 elsif not Is_Interface (Base_Type (Priv_Parent))
19290 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19293 ("parent of full type must descend from parent"
19294 & " of private extension", Full_Indic);
19296 -- First check a formal restriction, and then proceed with checking
19297 -- Ada rules. Since the formal restriction is not a serious error, we
19298 -- don't prevent further error detection for this check, hence the
19302 -- In formal mode, when completing a private extension the type
19303 -- named in the private part must be exactly the same as that
19304 -- named in the visible part.
19306 if Priv_Parent /= Full_Parent then
19307 Error_Msg_Name_1 := Chars (Priv_Parent);
19308 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19311 -- Check the rules of 7.3(10): if the private extension inherits
19312 -- known discriminants, then the full type must also inherit those
19313 -- discriminants from the same (ancestor) type, and the parent
19314 -- subtype of the full type must be constrained if and only if
19315 -- the ancestor subtype of the private extension is constrained.
19317 if No (Discriminant_Specifications (Parent (Priv_T)))
19318 and then not Has_Unknown_Discriminants (Priv_T)
19319 and then Has_Discriminants (Base_Type (Priv_Parent))
19322 Priv_Indic : constant Node_Id :=
19323 Subtype_Indication (Parent (Priv_T));
19325 Priv_Constr : constant Boolean :=
19326 Is_Constrained (Priv_Parent)
19328 Nkind (Priv_Indic) = N_Subtype_Indication
19330 Is_Constrained (Entity (Priv_Indic));
19332 Full_Constr : constant Boolean :=
19333 Is_Constrained (Full_Parent)
19335 Nkind (Full_Indic) = N_Subtype_Indication
19337 Is_Constrained (Entity (Full_Indic));
19339 Priv_Discr : Entity_Id;
19340 Full_Discr : Entity_Id;
19343 Priv_Discr := First_Discriminant (Priv_Parent);
19344 Full_Discr := First_Discriminant (Full_Parent);
19345 while Present (Priv_Discr) and then Present (Full_Discr) loop
19346 if Original_Record_Component (Priv_Discr) =
19347 Original_Record_Component (Full_Discr)
19349 Corresponding_Discriminant (Priv_Discr) =
19350 Corresponding_Discriminant (Full_Discr)
19357 Next_Discriminant (Priv_Discr);
19358 Next_Discriminant (Full_Discr);
19361 if Present (Priv_Discr) or else Present (Full_Discr) then
19363 ("full view must inherit discriminants of the parent"
19364 & " type used in the private extension", Full_Indic);
19366 elsif Priv_Constr and then not Full_Constr then
19368 ("parent subtype of full type must be constrained",
19371 elsif Full_Constr and then not Priv_Constr then
19373 ("parent subtype of full type must be unconstrained",
19378 -- Check the rules of 7.3(12): if a partial view has neither
19379 -- known or unknown discriminants, then the full type
19380 -- declaration shall define a definite subtype.
19382 elsif not Has_Unknown_Discriminants (Priv_T)
19383 and then not Has_Discriminants (Priv_T)
19384 and then not Is_Constrained (Full_T)
19387 ("full view must define a constrained type if partial view"
19388 & " has no discriminants", Full_T);
19391 -- ??????? Do we implement the following properly ?????
19392 -- If the ancestor subtype of a private extension has constrained
19393 -- discriminants, then the parent subtype of the full view shall
19394 -- impose a statically matching constraint on those discriminants
19399 -- For untagged types, verify that a type without discriminants is
19400 -- not completed with an unconstrained type. A separate error message
19401 -- is produced if the full type has defaulted discriminants.
19403 if not Is_Indefinite_Subtype (Priv_T)
19404 and then Is_Indefinite_Subtype (Full_T)
19406 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19408 ("full view of& not compatible with declaration#",
19411 if not Is_Tagged_Type (Full_T) then
19413 ("\one is constrained, the other unconstrained", Full_T);
19418 -- AI-419: verify that the use of "limited" is consistent
19421 Orig_Decl : constant Node_Id := Original_Node (N);
19424 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19425 and then not Limited_Present (Parent (Priv_T))
19426 and then not Synchronized_Present (Parent (Priv_T))
19427 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19429 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19430 and then Limited_Present (Type_Definition (Orig_Decl))
19433 ("full view of non-limited extension cannot be limited", N);
19437 -- Ada 2005 (AI-443): A synchronized private extension must be
19438 -- completed by a task or protected type.
19440 if Ada_Version >= Ada_2005
19441 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19442 and then Synchronized_Present (Parent (Priv_T))
19443 and then not Is_Concurrent_Type (Full_T)
19445 Error_Msg_N ("full view of synchronized extension must " &
19446 "be synchronized type", N);
19449 -- Ada 2005 AI-363: if the full view has discriminants with
19450 -- defaults, it is illegal to declare constrained access subtypes
19451 -- whose designated type is the current type. This allows objects
19452 -- of the type that are declared in the heap to be unconstrained.
19454 if not Has_Unknown_Discriminants (Priv_T)
19455 and then not Has_Discriminants (Priv_T)
19456 and then Has_Discriminants (Full_T)
19458 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19460 Set_Has_Constrained_Partial_View (Full_T);
19461 Set_Has_Constrained_Partial_View (Priv_T);
19464 -- Create a full declaration for all its subtypes recorded in
19465 -- Private_Dependents and swap them similarly to the base type. These
19466 -- are subtypes that have been define before the full declaration of
19467 -- the private type. We also swap the entry in Private_Dependents list
19468 -- so we can properly restore the private view on exit from the scope.
19471 Priv_Elmt : Elmt_Id;
19472 Priv_Scop : Entity_Id;
19477 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19478 while Present (Priv_Elmt) loop
19479 Priv := Node (Priv_Elmt);
19480 Priv_Scop := Scope (Priv);
19482 if Ekind_In (Priv, E_Private_Subtype,
19483 E_Limited_Private_Subtype,
19484 E_Record_Subtype_With_Private)
19486 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19487 Set_Is_Itype (Full);
19488 Set_Parent (Full, Parent (Priv));
19489 Set_Associated_Node_For_Itype (Full, N);
19491 -- Now we need to complete the private subtype, but since the
19492 -- base type has already been swapped, we must also swap the
19493 -- subtypes (and thus, reverse the arguments in the call to
19494 -- Complete_Private_Subtype). Also note that we may need to
19495 -- re-establish the scope of the private subtype.
19497 Copy_And_Swap (Priv, Full);
19499 if not In_Open_Scopes (Priv_Scop) then
19500 Push_Scope (Priv_Scop);
19503 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19505 Priv_Scop := Empty;
19508 Complete_Private_Subtype (Full, Priv, Full_T, N);
19510 if Present (Priv_Scop) then
19514 Replace_Elmt (Priv_Elmt, Full);
19517 Next_Elmt (Priv_Elmt);
19521 -- If the private view was tagged, copy the new primitive operations
19522 -- from the private view to the full view.
19524 if Is_Tagged_Type (Full_T) then
19526 Disp_Typ : Entity_Id;
19527 Full_List : Elist_Id;
19529 Prim_Elmt : Elmt_Id;
19530 Priv_List : Elist_Id;
19534 L : Elist_Id) return Boolean;
19535 -- Determine whether list L contains element E
19543 L : Elist_Id) return Boolean
19545 List_Elmt : Elmt_Id;
19548 List_Elmt := First_Elmt (L);
19549 while Present (List_Elmt) loop
19550 if Node (List_Elmt) = E then
19554 Next_Elmt (List_Elmt);
19560 -- Start of processing
19563 if Is_Tagged_Type (Priv_T) then
19564 Priv_List := Primitive_Operations (Priv_T);
19565 Prim_Elmt := First_Elmt (Priv_List);
19567 -- In the case of a concurrent type completing a private tagged
19568 -- type, primitives may have been declared in between the two
19569 -- views. These subprograms need to be wrapped the same way
19570 -- entries and protected procedures are handled because they
19571 -- cannot be directly shared by the two views.
19573 if Is_Concurrent_Type (Full_T) then
19575 Conc_Typ : constant Entity_Id :=
19576 Corresponding_Record_Type (Full_T);
19577 Curr_Nod : Node_Id := Parent (Conc_Typ);
19578 Wrap_Spec : Node_Id;
19581 while Present (Prim_Elmt) loop
19582 Prim := Node (Prim_Elmt);
19584 if Comes_From_Source (Prim)
19585 and then not Is_Abstract_Subprogram (Prim)
19588 Make_Subprogram_Declaration (Sloc (Prim),
19592 Obj_Typ => Conc_Typ,
19594 Parameter_Specifications (
19597 Insert_After (Curr_Nod, Wrap_Spec);
19598 Curr_Nod := Wrap_Spec;
19600 Analyze (Wrap_Spec);
19603 Next_Elmt (Prim_Elmt);
19609 -- For non-concurrent types, transfer explicit primitives, but
19610 -- omit those inherited from the parent of the private view
19611 -- since they will be re-inherited later on.
19614 Full_List := Primitive_Operations (Full_T);
19616 while Present (Prim_Elmt) loop
19617 Prim := Node (Prim_Elmt);
19619 if Comes_From_Source (Prim)
19620 and then not Contains (Prim, Full_List)
19622 Append_Elmt (Prim, Full_List);
19625 Next_Elmt (Prim_Elmt);
19629 -- Untagged private view
19632 Full_List := Primitive_Operations (Full_T);
19634 -- In this case the partial view is untagged, so here we locate
19635 -- all of the earlier primitives that need to be treated as
19636 -- dispatching (those that appear between the two views). Note
19637 -- that these additional operations must all be new operations
19638 -- (any earlier operations that override inherited operations
19639 -- of the full view will already have been inserted in the
19640 -- primitives list, marked by Check_Operation_From_Private_View
19641 -- as dispatching. Note that implicit "/=" operators are
19642 -- excluded from being added to the primitives list since they
19643 -- shouldn't be treated as dispatching (tagged "/=" is handled
19646 Prim := Next_Entity (Full_T);
19647 while Present (Prim) and then Prim /= Priv_T loop
19648 if Ekind_In (Prim, E_Procedure, E_Function) then
19649 Disp_Typ := Find_Dispatching_Type (Prim);
19651 if Disp_Typ = Full_T
19652 and then (Chars (Prim) /= Name_Op_Ne
19653 or else Comes_From_Source (Prim))
19655 Check_Controlling_Formals (Full_T, Prim);
19657 if not Is_Dispatching_Operation (Prim) then
19658 Append_Elmt (Prim, Full_List);
19659 Set_Is_Dispatching_Operation (Prim, True);
19660 Set_DT_Position (Prim, No_Uint);
19663 elsif Is_Dispatching_Operation (Prim)
19664 and then Disp_Typ /= Full_T
19667 -- Verify that it is not otherwise controlled by a
19668 -- formal or a return value of type T.
19670 Check_Controlling_Formals (Disp_Typ, Prim);
19674 Next_Entity (Prim);
19678 -- For the tagged case, the two views can share the same primitive
19679 -- operations list and the same class-wide type. Update attributes
19680 -- of the class-wide type which depend on the full declaration.
19682 if Is_Tagged_Type (Priv_T) then
19683 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19684 Set_Class_Wide_Type
19685 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19687 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19689 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19694 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19696 if Known_To_Have_Preelab_Init (Priv_T) then
19698 -- Case where there is a pragma Preelaborable_Initialization. We
19699 -- always allow this in predefined units, which is cheating a bit,
19700 -- but it means we don't have to struggle to meet the requirements in
19701 -- the RM for having Preelaborable Initialization. Otherwise we
19702 -- require that the type meets the RM rules. But we can't check that
19703 -- yet, because of the rule about overriding Initialize, so we simply
19704 -- set a flag that will be checked at freeze time.
19706 if not In_Predefined_Unit (Full_T) then
19707 Set_Must_Have_Preelab_Init (Full_T);
19711 -- If pragma CPP_Class was applied to the private type declaration,
19712 -- propagate it now to the full type declaration.
19714 if Is_CPP_Class (Priv_T) then
19715 Set_Is_CPP_Class (Full_T);
19716 Set_Convention (Full_T, Convention_CPP);
19718 -- Check that components of imported CPP types do not have default
19721 Check_CPP_Type_Has_No_Defaults (Full_T);
19724 -- If the private view has user specified stream attributes, then so has
19727 -- Why the test, how could these flags be already set in Full_T ???
19729 if Has_Specified_Stream_Read (Priv_T) then
19730 Set_Has_Specified_Stream_Read (Full_T);
19733 if Has_Specified_Stream_Write (Priv_T) then
19734 Set_Has_Specified_Stream_Write (Full_T);
19737 if Has_Specified_Stream_Input (Priv_T) then
19738 Set_Has_Specified_Stream_Input (Full_T);
19741 if Has_Specified_Stream_Output (Priv_T) then
19742 Set_Has_Specified_Stream_Output (Full_T);
19745 -- Propagate the attributes related to pragma Default_Initial_Condition
19746 -- from the private to the full view. Note that both flags are mutually
19749 if Has_Default_Init_Cond (Priv_T)
19750 or else Has_Inherited_Default_Init_Cond (Priv_T)
19752 Propagate_Default_Init_Cond_Attributes
19753 (From_Typ => Priv_T,
19755 Private_To_Full_View => True);
19757 -- In the case where the full view is derived from another private type,
19758 -- the attributes related to pragma Default_Initial_Condition must be
19759 -- propagated from the full to the private view to maintain consistency
19763 -- type Parent_Typ is private
19764 -- with Default_Initial_Condition ...;
19766 -- type Parent_Typ is ...;
19769 -- with Pack; use Pack;
19770 -- package Pack_2 is
19771 -- type Deriv_Typ is private; -- must inherit
19773 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19776 elsif Has_Default_Init_Cond (Full_T)
19777 or else Has_Inherited_Default_Init_Cond (Full_T)
19779 Propagate_Default_Init_Cond_Attributes
19780 (From_Typ => Full_T,
19782 Private_To_Full_View => True);
19785 -- Propagate the attributes related to pragma Ghost from the private to
19788 if Is_Ghost_Entity (Priv_T) then
19789 Set_Is_Ghost_Entity (Full_T);
19791 -- The Ghost policy in effect at the point of declaration and at the
19792 -- point of completion must match (SPARK RM 6.9(14)).
19794 Check_Ghost_Completion (Priv_T, Full_T);
19796 -- In the case where the private view of a tagged type lacks a parent
19797 -- type and is subject to pragma Ghost, ensure that the parent type
19798 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19800 if Is_Derived_Type (Full_T) then
19801 Check_Ghost_Derivation (Full_T);
19805 -- Propagate invariants to full type
19807 if Has_Invariants (Priv_T) then
19808 Set_Has_Invariants (Full_T);
19809 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
19812 if Has_Inheritable_Invariants (Priv_T) then
19813 Set_Has_Inheritable_Invariants (Full_T);
19816 -- Propagate predicates to full type, and predicate function if already
19817 -- defined. It is not clear that this can actually happen? the partial
19818 -- view cannot be frozen yet, and the predicate function has not been
19819 -- built. Still it is a cheap check and seems safer to make it.
19821 if Has_Predicates (Priv_T) then
19822 if Present (Predicate_Function (Priv_T)) then
19823 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
19826 Set_Has_Predicates (Full_T);
19828 end Process_Full_View;
19830 -----------------------------------
19831 -- Process_Incomplete_Dependents --
19832 -----------------------------------
19834 procedure Process_Incomplete_Dependents
19836 Full_T : Entity_Id;
19839 Inc_Elmt : Elmt_Id;
19840 Priv_Dep : Entity_Id;
19841 New_Subt : Entity_Id;
19843 Disc_Constraint : Elist_Id;
19846 if No (Private_Dependents (Inc_T)) then
19850 -- Itypes that may be generated by the completion of an incomplete
19851 -- subtype are not used by the back-end and not attached to the tree.
19852 -- They are created only for constraint-checking purposes.
19854 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
19855 while Present (Inc_Elmt) loop
19856 Priv_Dep := Node (Inc_Elmt);
19858 if Ekind (Priv_Dep) = E_Subprogram_Type then
19860 -- An Access_To_Subprogram type may have a return type or a
19861 -- parameter type that is incomplete. Replace with the full view.
19863 if Etype (Priv_Dep) = Inc_T then
19864 Set_Etype (Priv_Dep, Full_T);
19868 Formal : Entity_Id;
19871 Formal := First_Formal (Priv_Dep);
19872 while Present (Formal) loop
19873 if Etype (Formal) = Inc_T then
19874 Set_Etype (Formal, Full_T);
19877 Next_Formal (Formal);
19881 elsif Is_Overloadable (Priv_Dep) then
19883 -- If a subprogram in the incomplete dependents list is primitive
19884 -- for a tagged full type then mark it as a dispatching operation,
19885 -- check whether it overrides an inherited subprogram, and check
19886 -- restrictions on its controlling formals. Note that a protected
19887 -- operation is never dispatching: only its wrapper operation
19888 -- (which has convention Ada) is.
19890 if Is_Tagged_Type (Full_T)
19891 and then Is_Primitive (Priv_Dep)
19892 and then Convention (Priv_Dep) /= Convention_Protected
19894 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
19895 Set_Is_Dispatching_Operation (Priv_Dep);
19896 Check_Controlling_Formals (Full_T, Priv_Dep);
19899 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
19901 -- Can happen during processing of a body before the completion
19902 -- of a TA type. Ignore, because spec is also on dependent list.
19906 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
19907 -- corresponding subtype of the full view.
19909 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
19910 Set_Subtype_Indication
19911 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
19912 Set_Etype (Priv_Dep, Full_T);
19913 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
19914 Set_Analyzed (Parent (Priv_Dep), False);
19916 -- Reanalyze the declaration, suppressing the call to
19917 -- Enter_Name to avoid duplicate names.
19919 Analyze_Subtype_Declaration
19920 (N => Parent (Priv_Dep),
19923 -- Dependent is a subtype
19926 -- We build a new subtype indication using the full view of the
19927 -- incomplete parent. The discriminant constraints have been
19928 -- elaborated already at the point of the subtype declaration.
19930 New_Subt := Create_Itype (E_Void, N);
19932 if Has_Discriminants (Full_T) then
19933 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
19935 Disc_Constraint := No_Elist;
19938 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
19939 Set_Full_View (Priv_Dep, New_Subt);
19942 Next_Elmt (Inc_Elmt);
19944 end Process_Incomplete_Dependents;
19946 --------------------------------
19947 -- Process_Range_Expr_In_Decl --
19948 --------------------------------
19950 procedure Process_Range_Expr_In_Decl
19953 Subtyp : Entity_Id := Empty;
19954 Check_List : List_Id := Empty_List;
19955 R_Check_Off : Boolean := False;
19956 In_Iter_Schm : Boolean := False)
19959 R_Checks : Check_Result;
19960 Insert_Node : Node_Id;
19961 Def_Id : Entity_Id;
19964 Analyze_And_Resolve (R, Base_Type (T));
19966 if Nkind (R) = N_Range then
19968 -- In SPARK, all ranges should be static, with the exception of the
19969 -- discrete type definition of a loop parameter specification.
19971 if not In_Iter_Schm
19972 and then not Is_OK_Static_Range (R)
19974 Check_SPARK_05_Restriction ("range should be static", R);
19977 Lo := Low_Bound (R);
19978 Hi := High_Bound (R);
19980 -- Validity checks on the range of a quantified expression are
19981 -- delayed until the construct is transformed into a loop.
19983 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
19984 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
19988 -- We need to ensure validity of the bounds here, because if we
19989 -- go ahead and do the expansion, then the expanded code will get
19990 -- analyzed with range checks suppressed and we miss the check.
19992 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
19993 -- the temporaries generated by routine Remove_Side_Effects by means
19994 -- of validity checks must use the same names. When a range appears
19995 -- in the parent of a generic, the range is processed with checks
19996 -- disabled as part of the generic context and with checks enabled
19997 -- for code generation purposes. This leads to link issues as the
19998 -- generic contains references to xxx_FIRST/_LAST, but the inlined
19999 -- template sees the temporaries generated by Remove_Side_Effects.
20002 Validity_Check_Range (R, Subtyp);
20005 -- If there were errors in the declaration, try and patch up some
20006 -- common mistakes in the bounds. The cases handled are literals
20007 -- which are Integer where the expected type is Real and vice versa.
20008 -- These corrections allow the compilation process to proceed further
20009 -- along since some basic assumptions of the format of the bounds
20012 if Etype (R) = Any_Type then
20013 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20015 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20017 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20019 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20021 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20023 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20025 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20027 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20034 -- If the bounds of the range have been mistakenly given as string
20035 -- literals (perhaps in place of character literals), then an error
20036 -- has already been reported, but we rewrite the string literal as a
20037 -- bound of the range's type to avoid blowups in later processing
20038 -- that looks at static values.
20040 if Nkind (Lo) = N_String_Literal then
20042 Make_Attribute_Reference (Sloc (Lo),
20043 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20044 Attribute_Name => Name_First));
20045 Analyze_And_Resolve (Lo);
20048 if Nkind (Hi) = N_String_Literal then
20050 Make_Attribute_Reference (Sloc (Hi),
20051 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20052 Attribute_Name => Name_First));
20053 Analyze_And_Resolve (Hi);
20056 -- If bounds aren't scalar at this point then exit, avoiding
20057 -- problems with further processing of the range in this procedure.
20059 if not Is_Scalar_Type (Etype (Lo)) then
20063 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20064 -- then range of the base type. Here we check whether the bounds
20065 -- are in the range of the subtype itself. Note that if the bounds
20066 -- represent the null range the Constraint_Error exception should
20069 -- ??? The following code should be cleaned up as follows
20071 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20072 -- is done in the call to Range_Check (R, T); below
20074 -- 2. The use of R_Check_Off should be investigated and possibly
20075 -- removed, this would clean up things a bit.
20077 if Is_Null_Range (Lo, Hi) then
20081 -- Capture values of bounds and generate temporaries for them
20082 -- if needed, before applying checks, since checks may cause
20083 -- duplication of the expression without forcing evaluation.
20085 -- The forced evaluation removes side effects from expressions,
20086 -- which should occur also in GNATprove mode. Otherwise, we end up
20087 -- with unexpected insertions of actions at places where this is
20088 -- not supposed to occur, e.g. on default parameters of a call.
20090 if Expander_Active or GNATprove_Mode then
20092 -- If no subtype name, then just call Force_Evaluation to
20093 -- create declarations as needed to deal with side effects.
20094 -- Also ignore calls from within a record type, where we
20095 -- have possible scoping issues.
20097 if No (Subtyp) or else Is_Record_Type (Current_Scope) then
20098 Force_Evaluation (Lo);
20099 Force_Evaluation (Hi);
20101 -- If a subtype is given, then we capture the bounds if they
20102 -- are not known at compile time, using constant identifiers
20103 -- xxx_FIRST and xxx_LAST where xxx is the name of the subtype.
20105 -- Note: we do this transformation even if expansion is not
20106 -- active, and in particular we do it in GNATprove_Mode since
20107 -- the transformation is in general required to ensure that the
20108 -- resulting tree has proper Ada semantics.
20110 -- Historical note: We used to just do Force_Evaluation calls
20111 -- in all cases, but it is better to capture the bounds with
20112 -- proper non-serialized names, since these will be accessed
20113 -- from other units, and hence may be public, and also we can
20114 -- then expand 'First and 'Last references to be references to
20115 -- these special names.
20118 if not Compile_Time_Known_Value (Lo)
20120 -- No need to capture bounds if they already are
20121 -- references to constants.
20123 and then not (Is_Entity_Name (Lo)
20124 and then Is_Constant_Object (Entity (Lo)))
20127 Loc : constant Source_Ptr := Sloc (Lo);
20128 Lov : constant Entity_Id :=
20129 Make_Defining_Identifier (Loc,
20131 New_External_Name (Chars (Subtyp), "_FIRST"));
20134 Make_Object_Declaration (Loc,
20135 Defining_Identifier => Lov,
20136 Object_Definition =>
20137 New_Occurrence_Of (Base_Type (T), Loc),
20138 Constant_Present => True,
20139 Expression => Relocate_Node (Lo)));
20140 Rewrite (Lo, New_Occurrence_Of (Lov, Loc));
20144 if not Compile_Time_Known_Value (Hi)
20145 and then not (Is_Entity_Name (Hi)
20146 and then Is_Constant_Object (Entity (Hi)))
20149 Loc : constant Source_Ptr := Sloc (Hi);
20150 Hiv : constant Entity_Id :=
20151 Make_Defining_Identifier (Loc,
20153 New_External_Name (Chars (Subtyp), "_LAST"));
20156 Make_Object_Declaration (Loc,
20157 Defining_Identifier => Hiv,
20158 Object_Definition =>
20159 New_Occurrence_Of (Base_Type (T), Loc),
20160 Constant_Present => True,
20161 Expression => Relocate_Node (Hi)));
20162 Rewrite (Hi, New_Occurrence_Of (Hiv, Loc));
20168 -- We use a flag here instead of suppressing checks on the
20169 -- type because the type we check against isn't necessarily
20170 -- the place where we put the check.
20172 if not R_Check_Off then
20173 R_Checks := Get_Range_Checks (R, T);
20175 -- Look up tree to find an appropriate insertion point. We
20176 -- can't just use insert_actions because later processing
20177 -- depends on the insertion node. Prior to Ada 2012 the
20178 -- insertion point could only be a declaration or a loop, but
20179 -- quantified expressions can appear within any context in an
20180 -- expression, and the insertion point can be any statement,
20181 -- pragma, or declaration.
20183 Insert_Node := Parent (R);
20184 while Present (Insert_Node) loop
20186 Nkind (Insert_Node) in N_Declaration
20189 (Insert_Node, N_Component_Declaration,
20190 N_Loop_Parameter_Specification,
20191 N_Function_Specification,
20192 N_Procedure_Specification);
20194 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20195 or else Nkind (Insert_Node) in
20196 N_Statement_Other_Than_Procedure_Call
20197 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20200 Insert_Node := Parent (Insert_Node);
20203 -- Why would Type_Decl not be present??? Without this test,
20204 -- short regression tests fail.
20206 if Present (Insert_Node) then
20208 -- Case of loop statement. Verify that the range is part
20209 -- of the subtype indication of the iteration scheme.
20211 if Nkind (Insert_Node) = N_Loop_Statement then
20216 Indic := Parent (R);
20217 while Present (Indic)
20218 and then Nkind (Indic) /= N_Subtype_Indication
20220 Indic := Parent (Indic);
20223 if Present (Indic) then
20224 Def_Id := Etype (Subtype_Mark (Indic));
20226 Insert_Range_Checks
20230 Sloc (Insert_Node),
20232 Do_Before => True);
20236 -- Insertion before a declaration. If the declaration
20237 -- includes discriminants, the list of applicable checks
20238 -- is given by the caller.
20240 elsif Nkind (Insert_Node) in N_Declaration then
20241 Def_Id := Defining_Identifier (Insert_Node);
20243 if (Ekind (Def_Id) = E_Record_Type
20244 and then Depends_On_Discriminant (R))
20246 (Ekind (Def_Id) = E_Protected_Type
20247 and then Has_Discriminants (Def_Id))
20249 Append_Range_Checks
20251 Check_List, Def_Id, Sloc (Insert_Node), R);
20254 Insert_Range_Checks
20256 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20260 -- Insertion before a statement. Range appears in the
20261 -- context of a quantified expression. Insertion will
20262 -- take place when expression is expanded.
20271 -- Case of other than an explicit N_Range node
20273 -- The forced evaluation removes side effects from expressions, which
20274 -- should occur also in GNATprove mode. Otherwise, we end up with
20275 -- unexpected insertions of actions at places where this is not
20276 -- supposed to occur, e.g. on default parameters of a call.
20278 elsif Expander_Active or GNATprove_Mode then
20279 Get_Index_Bounds (R, Lo, Hi);
20280 Force_Evaluation (Lo);
20281 Force_Evaluation (Hi);
20283 end Process_Range_Expr_In_Decl;
20285 --------------------------------------
20286 -- Process_Real_Range_Specification --
20287 --------------------------------------
20289 procedure Process_Real_Range_Specification (Def : Node_Id) is
20290 Spec : constant Node_Id := Real_Range_Specification (Def);
20293 Err : Boolean := False;
20295 procedure Analyze_Bound (N : Node_Id);
20296 -- Analyze and check one bound
20298 -------------------
20299 -- Analyze_Bound --
20300 -------------------
20302 procedure Analyze_Bound (N : Node_Id) is
20304 Analyze_And_Resolve (N, Any_Real);
20306 if not Is_OK_Static_Expression (N) then
20307 Flag_Non_Static_Expr
20308 ("bound in real type definition is not static!", N);
20313 -- Start of processing for Process_Real_Range_Specification
20316 if Present (Spec) then
20317 Lo := Low_Bound (Spec);
20318 Hi := High_Bound (Spec);
20319 Analyze_Bound (Lo);
20320 Analyze_Bound (Hi);
20322 -- If error, clear away junk range specification
20325 Set_Real_Range_Specification (Def, Empty);
20328 end Process_Real_Range_Specification;
20330 ---------------------
20331 -- Process_Subtype --
20332 ---------------------
20334 function Process_Subtype
20336 Related_Nod : Node_Id;
20337 Related_Id : Entity_Id := Empty;
20338 Suffix : Character := ' ') return Entity_Id
20341 Def_Id : Entity_Id;
20342 Error_Node : Node_Id;
20343 Full_View_Id : Entity_Id;
20344 Subtype_Mark_Id : Entity_Id;
20346 May_Have_Null_Exclusion : Boolean;
20348 procedure Check_Incomplete (T : Entity_Id);
20349 -- Called to verify that an incomplete type is not used prematurely
20351 ----------------------
20352 -- Check_Incomplete --
20353 ----------------------
20355 procedure Check_Incomplete (T : Entity_Id) is
20357 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20359 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20361 not (Ada_Version >= Ada_2005
20363 (Nkind (Parent (T)) = N_Subtype_Declaration
20364 or else (Nkind (Parent (T)) = N_Subtype_Indication
20365 and then Nkind (Parent (Parent (T))) =
20366 N_Subtype_Declaration)))
20368 Error_Msg_N ("invalid use of type before its full declaration", T);
20370 end Check_Incomplete;
20372 -- Start of processing for Process_Subtype
20375 -- Case of no constraints present
20377 if Nkind (S) /= N_Subtype_Indication then
20379 Check_Incomplete (S);
20382 -- Ada 2005 (AI-231): Static check
20384 if Ada_Version >= Ada_2005
20385 and then Present (P)
20386 and then Null_Exclusion_Present (P)
20387 and then Nkind (P) /= N_Access_To_Object_Definition
20388 and then not Is_Access_Type (Entity (S))
20390 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20393 -- The following is ugly, can't we have a range or even a flag???
20395 May_Have_Null_Exclusion :=
20396 Nkind_In (P, N_Access_Definition,
20397 N_Access_Function_Definition,
20398 N_Access_Procedure_Definition,
20399 N_Access_To_Object_Definition,
20401 N_Component_Definition)
20403 Nkind_In (P, N_Derived_Type_Definition,
20404 N_Discriminant_Specification,
20405 N_Formal_Object_Declaration,
20406 N_Object_Declaration,
20407 N_Object_Renaming_Declaration,
20408 N_Parameter_Specification,
20409 N_Subtype_Declaration);
20411 -- Create an Itype that is a duplicate of Entity (S) but with the
20412 -- null-exclusion attribute.
20414 if May_Have_Null_Exclusion
20415 and then Is_Access_Type (Entity (S))
20416 and then Null_Exclusion_Present (P)
20418 -- No need to check the case of an access to object definition.
20419 -- It is correct to define double not-null pointers.
20422 -- type Not_Null_Int_Ptr is not null access Integer;
20423 -- type Acc is not null access Not_Null_Int_Ptr;
20425 and then Nkind (P) /= N_Access_To_Object_Definition
20427 if Can_Never_Be_Null (Entity (S)) then
20428 case Nkind (Related_Nod) is
20429 when N_Full_Type_Declaration =>
20430 if Nkind (Type_Definition (Related_Nod))
20431 in N_Array_Type_Definition
20435 (Component_Definition
20436 (Type_Definition (Related_Nod)));
20439 Subtype_Indication (Type_Definition (Related_Nod));
20442 when N_Subtype_Declaration =>
20443 Error_Node := Subtype_Indication (Related_Nod);
20445 when N_Object_Declaration =>
20446 Error_Node := Object_Definition (Related_Nod);
20448 when N_Component_Declaration =>
20450 Subtype_Indication (Component_Definition (Related_Nod));
20452 when N_Allocator =>
20453 Error_Node := Expression (Related_Nod);
20456 pragma Assert (False);
20457 Error_Node := Related_Nod;
20461 ("`NOT NULL` not allowed (& already excludes null)",
20467 Create_Null_Excluding_Itype
20469 Related_Nod => P));
20470 Set_Entity (S, Etype (S));
20475 -- Case of constraint present, so that we have an N_Subtype_Indication
20476 -- node (this node is created only if constraints are present).
20479 Find_Type (Subtype_Mark (S));
20481 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20483 (Nkind (Parent (S)) = N_Subtype_Declaration
20484 and then Is_Itype (Defining_Identifier (Parent (S))))
20486 Check_Incomplete (Subtype_Mark (S));
20490 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20492 -- Explicit subtype declaration case
20494 if Nkind (P) = N_Subtype_Declaration then
20495 Def_Id := Defining_Identifier (P);
20497 -- Explicit derived type definition case
20499 elsif Nkind (P) = N_Derived_Type_Definition then
20500 Def_Id := Defining_Identifier (Parent (P));
20502 -- Implicit case, the Def_Id must be created as an implicit type.
20503 -- The one exception arises in the case of concurrent types, array
20504 -- and access types, where other subsidiary implicit types may be
20505 -- created and must appear before the main implicit type. In these
20506 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20507 -- has not yet been called to create Def_Id.
20510 if Is_Array_Type (Subtype_Mark_Id)
20511 or else Is_Concurrent_Type (Subtype_Mark_Id)
20512 or else Is_Access_Type (Subtype_Mark_Id)
20516 -- For the other cases, we create a new unattached Itype,
20517 -- and set the indication to ensure it gets attached later.
20521 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20525 -- If the kind of constraint is invalid for this kind of type,
20526 -- then give an error, and then pretend no constraint was given.
20528 if not Is_Valid_Constraint_Kind
20529 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20532 ("incorrect constraint for this kind of type", Constraint (S));
20534 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20536 -- Set Ekind of orphan itype, to prevent cascaded errors
20538 if Present (Def_Id) then
20539 Set_Ekind (Def_Id, Ekind (Any_Type));
20542 -- Make recursive call, having got rid of the bogus constraint
20544 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20547 -- Remaining processing depends on type. Select on Base_Type kind to
20548 -- ensure getting to the concrete type kind in the case of a private
20549 -- subtype (needed when only doing semantic analysis).
20551 case Ekind (Base_Type (Subtype_Mark_Id)) is
20552 when Access_Kind =>
20554 -- If this is a constraint on a class-wide type, discard it.
20555 -- There is currently no way to express a partial discriminant
20556 -- constraint on a type with unknown discriminants. This is
20557 -- a pathology that the ACATS wisely decides not to test.
20559 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20560 if Comes_From_Source (S) then
20562 ("constraint on class-wide type ignored??",
20566 if Nkind (P) = N_Subtype_Declaration then
20567 Set_Subtype_Indication (P,
20568 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20571 return Subtype_Mark_Id;
20574 Constrain_Access (Def_Id, S, Related_Nod);
20577 and then Is_Itype (Designated_Type (Def_Id))
20578 and then Nkind (Related_Nod) = N_Subtype_Declaration
20579 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20581 Build_Itype_Reference
20582 (Designated_Type (Def_Id), Related_Nod);
20586 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20588 when Decimal_Fixed_Point_Kind =>
20589 Constrain_Decimal (Def_Id, S);
20591 when Enumeration_Kind =>
20592 Constrain_Enumeration (Def_Id, S);
20593 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20595 when Ordinary_Fixed_Point_Kind =>
20596 Constrain_Ordinary_Fixed (Def_Id, S);
20599 Constrain_Float (Def_Id, S);
20601 when Integer_Kind =>
20602 Constrain_Integer (Def_Id, S);
20603 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20605 when E_Record_Type |
20608 E_Incomplete_Type =>
20609 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20611 if Ekind (Def_Id) = E_Incomplete_Type then
20612 Set_Private_Dependents (Def_Id, New_Elmt_List);
20615 when Private_Kind =>
20616 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20617 Set_Private_Dependents (Def_Id, New_Elmt_List);
20619 -- In case of an invalid constraint prevent further processing
20620 -- since the type constructed is missing expected fields.
20622 if Etype (Def_Id) = Any_Type then
20626 -- If the full view is that of a task with discriminants,
20627 -- we must constrain both the concurrent type and its
20628 -- corresponding record type. Otherwise we will just propagate
20629 -- the constraint to the full view, if available.
20631 if Present (Full_View (Subtype_Mark_Id))
20632 and then Has_Discriminants (Subtype_Mark_Id)
20633 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20636 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20638 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20639 Constrain_Concurrent (Full_View_Id, S,
20640 Related_Nod, Related_Id, Suffix);
20641 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20642 Set_Full_View (Def_Id, Full_View_Id);
20644 -- Introduce an explicit reference to the private subtype,
20645 -- to prevent scope anomalies in gigi if first use appears
20646 -- in a nested context, e.g. a later function body.
20647 -- Should this be generated in other contexts than a full
20648 -- type declaration?
20650 if Is_Itype (Def_Id)
20652 Nkind (Parent (P)) = N_Full_Type_Declaration
20654 Build_Itype_Reference (Def_Id, Parent (P));
20658 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20661 when Concurrent_Kind =>
20662 Constrain_Concurrent (Def_Id, S,
20663 Related_Nod, Related_Id, Suffix);
20666 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20669 -- Size and Convention are always inherited from the base type
20671 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20672 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20676 end Process_Subtype;
20678 --------------------------------------------
20679 -- Propagate_Default_Init_Cond_Attributes --
20680 --------------------------------------------
20682 procedure Propagate_Default_Init_Cond_Attributes
20683 (From_Typ : Entity_Id;
20684 To_Typ : Entity_Id;
20685 Parent_To_Derivation : Boolean := False;
20686 Private_To_Full_View : Boolean := False)
20688 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20689 -- Remove the default initial procedure (if any) from the rep chain of
20692 ----------------------------------------
20693 -- Remove_Default_Init_Cond_Procedure --
20694 ----------------------------------------
20696 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20697 Found : Boolean := False;
20703 Subp := Subprograms_For_Type (Typ);
20704 while Present (Subp) loop
20705 if Is_Default_Init_Cond_Procedure (Subp) then
20711 Subp := Subprograms_For_Type (Subp);
20715 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20716 Set_Subprograms_For_Type (Subp, Empty);
20718 end Remove_Default_Init_Cond_Procedure;
20722 Inherit_Procedure : Boolean := False;
20724 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20727 if Has_Default_Init_Cond (From_Typ) then
20729 -- A derived type inherits the attributes from its parent type
20731 if Parent_To_Derivation then
20732 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20734 -- A full view shares the attributes with its private view
20737 Set_Has_Default_Init_Cond (To_Typ);
20740 Inherit_Procedure := True;
20742 -- Due to the order of expansion, a derived private type is processed
20743 -- by two routines which both attempt to set the attributes related
20744 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20745 -- Process_Full_View.
20748 -- type Parent_Typ is private
20749 -- with Default_Initial_Condition ...;
20751 -- type Parent_Typ is ...;
20754 -- with Pack; use Pack;
20755 -- package Pack_2 is
20756 -- type Deriv_Typ is private
20757 -- with Default_Initial_Condition ...;
20759 -- type Deriv_Typ is new Parent_Typ;
20762 -- When Build_Derived_Type operates, it sets the attributes on the
20763 -- full view without taking into account that the private view may
20764 -- define its own default initial condition procedure. This becomes
20765 -- apparent in Process_Full_View which must undo some of the work by
20766 -- Build_Derived_Type and propagate the attributes from the private
20767 -- to the full view.
20769 if Private_To_Full_View then
20770 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20771 Remove_Default_Init_Cond_Procedure (To_Typ);
20774 -- A type must inherit the default initial condition procedure from a
20775 -- parent type when the parent itself is inheriting the procedure or
20776 -- when it is defining one. This circuitry is also used when dealing
20777 -- with the private / full view of a type.
20779 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20780 or (Parent_To_Derivation
20781 and Present (Get_Pragma
20782 (From_Typ, Pragma_Default_Initial_Condition)))
20784 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20785 Inherit_Procedure := True;
20788 if Inherit_Procedure
20789 and then No (Default_Init_Cond_Procedure (To_Typ))
20791 Set_Default_Init_Cond_Procedure
20792 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20794 end Propagate_Default_Init_Cond_Attributes;
20796 -----------------------------
20797 -- Record_Type_Declaration --
20798 -----------------------------
20800 procedure Record_Type_Declaration
20805 Def : constant Node_Id := Type_Definition (N);
20806 Is_Tagged : Boolean;
20807 Tag_Comp : Entity_Id;
20810 -- These flags must be initialized before calling Process_Discriminants
20811 -- because this routine makes use of them.
20813 Set_Ekind (T, E_Record_Type);
20815 Init_Size_Align (T);
20816 Set_Interfaces (T, No_Elist);
20817 Set_Stored_Constraint (T, No_Elist);
20818 Set_Default_SSO (T);
20822 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20823 if Limited_Present (Def) then
20824 Check_SPARK_05_Restriction ("limited is not allowed", N);
20827 if Abstract_Present (Def) then
20828 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20831 -- The flag Is_Tagged_Type might have already been set by
20832 -- Find_Type_Name if it detected an error for declaration T. This
20833 -- arises in the case of private tagged types where the full view
20834 -- omits the word tagged.
20837 Tagged_Present (Def)
20838 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20840 Set_Is_Limited_Record (T, Limited_Present (Def));
20843 Set_Is_Tagged_Type (T, True);
20844 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
20847 -- Type is abstract if full declaration carries keyword, or if
20848 -- previous partial view did.
20850 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20851 or else Abstract_Present (Def));
20854 Check_SPARK_05_Restriction ("interface is not allowed", N);
20857 Analyze_Interface_Declaration (T, Def);
20859 if Present (Discriminant_Specifications (N)) then
20861 ("interface types cannot have discriminants",
20862 Defining_Identifier
20863 (First (Discriminant_Specifications (N))));
20867 -- First pass: if there are self-referential access components,
20868 -- create the required anonymous access type declarations, and if
20869 -- need be an incomplete type declaration for T itself.
20871 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20873 if Ada_Version >= Ada_2005
20874 and then Present (Interface_List (Def))
20876 Check_Interfaces (N, Def);
20879 Ifaces_List : Elist_Id;
20882 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20883 -- already in the parents.
20887 Ifaces_List => Ifaces_List,
20888 Exclude_Parents => True);
20890 Set_Interfaces (T, Ifaces_List);
20894 -- Records constitute a scope for the component declarations within.
20895 -- The scope is created prior to the processing of these declarations.
20896 -- Discriminants are processed first, so that they are visible when
20897 -- processing the other components. The Ekind of the record type itself
20898 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20900 -- Enter record scope
20904 -- If an incomplete or private type declaration was already given for
20905 -- the type, then this scope already exists, and the discriminants have
20906 -- been declared within. We must verify that the full declaration
20907 -- matches the incomplete one.
20909 Check_Or_Process_Discriminants (N, T, Prev);
20911 Set_Is_Constrained (T, not Has_Discriminants (T));
20912 Set_Has_Delayed_Freeze (T, True);
20914 -- For tagged types add a manually analyzed component corresponding
20915 -- to the component _tag, the corresponding piece of tree will be
20916 -- expanded as part of the freezing actions if it is not a CPP_Class.
20920 -- Do not add the tag unless we are in expansion mode
20922 if Expander_Active then
20923 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20924 Enter_Name (Tag_Comp);
20926 Set_Ekind (Tag_Comp, E_Component);
20927 Set_Is_Tag (Tag_Comp);
20928 Set_Is_Aliased (Tag_Comp);
20929 Set_Etype (Tag_Comp, RTE (RE_Tag));
20930 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20931 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20932 Init_Component_Location (Tag_Comp);
20934 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20935 -- implemented interfaces.
20937 if Has_Interfaces (T) then
20938 Add_Interface_Tag_Components (N, T);
20942 Make_Class_Wide_Type (T);
20943 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20946 -- We must suppress range checks when processing record components in
20947 -- the presence of discriminants, since we don't want spurious checks to
20948 -- be generated during their analysis, but Suppress_Range_Checks flags
20949 -- must be reset the after processing the record definition.
20951 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20952 -- couldn't we just use the normal range check suppression method here.
20953 -- That would seem cleaner ???
20955 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20956 Set_Kill_Range_Checks (T, True);
20957 Record_Type_Definition (Def, Prev);
20958 Set_Kill_Range_Checks (T, False);
20960 Record_Type_Definition (Def, Prev);
20963 -- Exit from record scope
20967 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20968 -- the implemented interfaces and associate them an aliased entity.
20971 and then not Is_Empty_List (Interface_List (Def))
20973 Derive_Progenitor_Subprograms (T, T);
20976 Check_Function_Writable_Actuals (N);
20977 end Record_Type_Declaration;
20979 ----------------------------
20980 -- Record_Type_Definition --
20981 ----------------------------
20983 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20984 Component : Entity_Id;
20985 Ctrl_Components : Boolean := False;
20986 Final_Storage_Only : Boolean;
20990 if Ekind (Prev_T) = E_Incomplete_Type then
20991 T := Full_View (Prev_T);
20996 -- In SPARK, tagged types and type extensions may only be declared in
20997 -- the specification of library unit packages.
20999 if Present (Def) and then Is_Tagged_Type (T) then
21005 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21006 Typ := Parent (Def);
21009 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21010 Typ := Parent (Parent (Def));
21013 Ctxt := Parent (Typ);
21015 if Nkind (Ctxt) = N_Package_Body
21016 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21018 Check_SPARK_05_Restriction
21019 ("type should be defined in package specification", Typ);
21021 elsif Nkind (Ctxt) /= N_Package_Specification
21022 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21024 Check_SPARK_05_Restriction
21025 ("type should be defined in library unit package", Typ);
21030 Final_Storage_Only := not Is_Controlled (T);
21032 -- Ada 2005: Check whether an explicit Limited is present in a derived
21033 -- type declaration.
21035 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21036 and then Limited_Present (Parent (Def))
21038 Set_Is_Limited_Record (T);
21041 -- If the component list of a record type is defined by the reserved
21042 -- word null and there is no discriminant part, then the record type has
21043 -- no components and all records of the type are null records (RM 3.7)
21044 -- This procedure is also called to process the extension part of a
21045 -- record extension, in which case the current scope may have inherited
21049 or else No (Component_List (Def))
21050 or else Null_Present (Component_List (Def))
21052 if not Is_Tagged_Type (T) then
21053 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21057 Analyze_Declarations (Component_Items (Component_List (Def)));
21059 if Present (Variant_Part (Component_List (Def))) then
21060 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21061 Analyze (Variant_Part (Component_List (Def)));
21065 -- After completing the semantic analysis of the record definition,
21066 -- record components, both new and inherited, are accessible. Set their
21067 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21068 -- whose Ekind may be void.
21070 Component := First_Entity (Current_Scope);
21071 while Present (Component) loop
21072 if Ekind (Component) = E_Void
21073 and then not Is_Itype (Component)
21075 Set_Ekind (Component, E_Component);
21076 Init_Component_Location (Component);
21079 if Has_Task (Etype (Component)) then
21083 if Has_Protected (Etype (Component)) then
21084 Set_Has_Protected (T);
21087 if Ekind (Component) /= E_Component then
21090 -- Do not set Has_Controlled_Component on a class-wide equivalent
21091 -- type. See Make_CW_Equivalent_Type.
21093 elsif not Is_Class_Wide_Equivalent_Type (T)
21094 and then (Has_Controlled_Component (Etype (Component))
21095 or else (Chars (Component) /= Name_uParent
21096 and then Is_Controlled (Etype (Component))))
21098 Set_Has_Controlled_Component (T, True);
21099 Final_Storage_Only :=
21101 and then Finalize_Storage_Only (Etype (Component));
21102 Ctrl_Components := True;
21105 Next_Entity (Component);
21108 -- A Type is Finalize_Storage_Only only if all its controlled components
21111 if Ctrl_Components then
21112 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21115 -- Place reference to end record on the proper entity, which may
21116 -- be a partial view.
21118 if Present (Def) then
21119 Process_End_Label (Def, 'e', Prev_T);
21121 end Record_Type_Definition;
21123 ------------------------
21124 -- Replace_Components --
21125 ------------------------
21127 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21128 function Process (N : Node_Id) return Traverse_Result;
21134 function Process (N : Node_Id) return Traverse_Result is
21138 if Nkind (N) = N_Discriminant_Specification then
21139 Comp := First_Discriminant (Typ);
21140 while Present (Comp) loop
21141 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21142 Set_Defining_Identifier (N, Comp);
21146 Next_Discriminant (Comp);
21149 elsif Nkind (N) = N_Component_Declaration then
21150 Comp := First_Component (Typ);
21151 while Present (Comp) loop
21152 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21153 Set_Defining_Identifier (N, Comp);
21157 Next_Component (Comp);
21164 procedure Replace is new Traverse_Proc (Process);
21166 -- Start of processing for Replace_Components
21170 end Replace_Components;
21172 -------------------------------
21173 -- Set_Completion_Referenced --
21174 -------------------------------
21176 procedure Set_Completion_Referenced (E : Entity_Id) is
21178 -- If in main unit, mark entity that is a completion as referenced,
21179 -- warnings go on the partial view when needed.
21181 if In_Extended_Main_Source_Unit (E) then
21182 Set_Referenced (E);
21184 end Set_Completion_Referenced;
21186 ---------------------
21187 -- Set_Default_SSO --
21188 ---------------------
21190 procedure Set_Default_SSO (T : Entity_Id) is
21192 case Opt.Default_SSO is
21196 Set_SSO_Set_Low_By_Default (T, True);
21198 Set_SSO_Set_High_By_Default (T, True);
21200 raise Program_Error;
21202 end Set_Default_SSO;
21204 ---------------------
21205 -- Set_Fixed_Range --
21206 ---------------------
21208 -- The range for fixed-point types is complicated by the fact that we
21209 -- do not know the exact end points at the time of the declaration. This
21210 -- is true for three reasons:
21212 -- A size clause may affect the fudging of the end-points.
21213 -- A small clause may affect the values of the end-points.
21214 -- We try to include the end-points if it does not affect the size.
21216 -- This means that the actual end-points must be established at the
21217 -- point when the type is frozen. Meanwhile, we first narrow the range
21218 -- as permitted (so that it will fit if necessary in a small specified
21219 -- size), and then build a range subtree with these narrowed bounds.
21220 -- Set_Fixed_Range constructs the range from real literal values, and
21221 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21223 -- The parent of this range is set to point to the entity so that it is
21224 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21225 -- other scalar types, which are just pointers to the range in the
21226 -- original tree, this would otherwise be an orphan).
21228 -- The tree is left unanalyzed. When the type is frozen, the processing
21229 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21230 -- analyzed, and uses this as an indication that it should complete
21231 -- work on the range (it will know the final small and size values).
21233 procedure Set_Fixed_Range
21239 S : constant Node_Id :=
21241 Low_Bound => Make_Real_Literal (Loc, Lo),
21242 High_Bound => Make_Real_Literal (Loc, Hi));
21244 Set_Scalar_Range (E, S);
21247 -- Before the freeze point, the bounds of a fixed point are universal
21248 -- and carry the corresponding type.
21250 Set_Etype (Low_Bound (S), Universal_Real);
21251 Set_Etype (High_Bound (S), Universal_Real);
21252 end Set_Fixed_Range;
21254 ----------------------------------
21255 -- Set_Scalar_Range_For_Subtype --
21256 ----------------------------------
21258 procedure Set_Scalar_Range_For_Subtype
21259 (Def_Id : Entity_Id;
21263 Kind : constant Entity_Kind := Ekind (Def_Id);
21266 -- Defend against previous error
21268 if Nkind (R) = N_Error then
21272 Set_Scalar_Range (Def_Id, R);
21274 -- We need to link the range into the tree before resolving it so
21275 -- that types that are referenced, including importantly the subtype
21276 -- itself, are properly frozen (Freeze_Expression requires that the
21277 -- expression be properly linked into the tree). Of course if it is
21278 -- already linked in, then we do not disturb the current link.
21280 if No (Parent (R)) then
21281 Set_Parent (R, Def_Id);
21284 -- Reset the kind of the subtype during analysis of the range, to
21285 -- catch possible premature use in the bounds themselves.
21287 Set_Ekind (Def_Id, E_Void);
21288 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21289 Set_Ekind (Def_Id, Kind);
21290 end Set_Scalar_Range_For_Subtype;
21292 --------------------------------------------------------
21293 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21294 --------------------------------------------------------
21296 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21300 -- Make sure set if encountered during Expand_To_Stored_Constraint
21302 Set_Stored_Constraint (E, No_Elist);
21304 -- Give it the right value
21306 if Is_Constrained (E) and then Has_Discriminants (E) then
21307 Set_Stored_Constraint (E,
21308 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21310 end Set_Stored_Constraint_From_Discriminant_Constraint;
21312 -------------------------------------
21313 -- Signed_Integer_Type_Declaration --
21314 -------------------------------------
21316 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21317 Implicit_Base : Entity_Id;
21318 Base_Typ : Entity_Id;
21321 Errs : Boolean := False;
21325 function Can_Derive_From (E : Entity_Id) return Boolean;
21326 -- Determine whether given bounds allow derivation from specified type
21328 procedure Check_Bound (Expr : Node_Id);
21329 -- Check bound to make sure it is integral and static. If not, post
21330 -- appropriate error message and set Errs flag
21332 ---------------------
21333 -- Can_Derive_From --
21334 ---------------------
21336 -- Note we check both bounds against both end values, to deal with
21337 -- strange types like ones with a range of 0 .. -12341234.
21339 function Can_Derive_From (E : Entity_Id) return Boolean is
21340 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21341 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21343 return Lo <= Lo_Val and then Lo_Val <= Hi
21345 Lo <= Hi_Val and then Hi_Val <= Hi;
21346 end Can_Derive_From;
21352 procedure Check_Bound (Expr : Node_Id) is
21354 -- If a range constraint is used as an integer type definition, each
21355 -- bound of the range must be defined by a static expression of some
21356 -- integer type, but the two bounds need not have the same integer
21357 -- type (Negative bounds are allowed.) (RM 3.5.4)
21359 if not Is_Integer_Type (Etype (Expr)) then
21361 ("integer type definition bounds must be of integer type", Expr);
21364 elsif not Is_OK_Static_Expression (Expr) then
21365 Flag_Non_Static_Expr
21366 ("non-static expression used for integer type bound!", Expr);
21369 -- The bounds are folded into literals, and we set their type to be
21370 -- universal, to avoid typing difficulties: we cannot set the type
21371 -- of the literal to the new type, because this would be a forward
21372 -- reference for the back end, and if the original type is user-
21373 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21376 if Is_Entity_Name (Expr) then
21377 Fold_Uint (Expr, Expr_Value (Expr), True);
21380 Set_Etype (Expr, Universal_Integer);
21384 -- Start of processing for Signed_Integer_Type_Declaration
21387 -- Create an anonymous base type
21390 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21392 -- Analyze and check the bounds, they can be of any integer type
21394 Lo := Low_Bound (Def);
21395 Hi := High_Bound (Def);
21397 -- Arbitrarily use Integer as the type if either bound had an error
21399 if Hi = Error or else Lo = Error then
21400 Base_Typ := Any_Integer;
21401 Set_Error_Posted (T, True);
21403 -- Here both bounds are OK expressions
21406 Analyze_And_Resolve (Lo, Any_Integer);
21407 Analyze_And_Resolve (Hi, Any_Integer);
21413 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21414 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21417 -- Find type to derive from
21419 Lo_Val := Expr_Value (Lo);
21420 Hi_Val := Expr_Value (Hi);
21422 if Can_Derive_From (Standard_Short_Short_Integer) then
21423 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21425 elsif Can_Derive_From (Standard_Short_Integer) then
21426 Base_Typ := Base_Type (Standard_Short_Integer);
21428 elsif Can_Derive_From (Standard_Integer) then
21429 Base_Typ := Base_Type (Standard_Integer);
21431 elsif Can_Derive_From (Standard_Long_Integer) then
21432 Base_Typ := Base_Type (Standard_Long_Integer);
21434 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21435 Check_Restriction (No_Long_Long_Integers, Def);
21436 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21439 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21440 Error_Msg_N ("integer type definition bounds out of range", Def);
21441 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21442 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21446 -- Complete both implicit base and declared first subtype entities. The
21447 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21448 -- are not clobbered when the signed integer type acts as a full view of
21451 Set_Etype (Implicit_Base, Base_Typ);
21452 Set_Size_Info (Implicit_Base, Base_Typ);
21453 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21454 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21455 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21457 Set_Ekind (T, E_Signed_Integer_Subtype);
21458 Set_Etype (T, Implicit_Base);
21459 Set_Size_Info (T, Implicit_Base);
21460 Inherit_Rep_Item_Chain (T, Implicit_Base);
21461 Set_Scalar_Range (T, Def);
21462 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21463 Set_Is_Constrained (T);
21464 end Signed_Integer_Type_Declaration;