1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2003, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree
; use Atree
;
28 with Checks
; use Checks
;
29 with Elists
; use Elists
;
30 with Einfo
; use Einfo
;
31 with Errout
; use Errout
;
32 with Eval_Fat
; use Eval_Fat
;
33 with Exp_Ch3
; use Exp_Ch3
;
34 with Exp_Dist
; use Exp_Dist
;
35 with Exp_Tss
; use Exp_Tss
;
36 with Exp_Util
; use Exp_Util
;
37 with Freeze
; use Freeze
;
38 with Itypes
; use Itypes
;
39 with Layout
; use Layout
;
41 with Lib
.Xref
; use Lib
.Xref
;
42 with Namet
; use Namet
;
43 with Nmake
; use Nmake
;
45 with Restrict
; use Restrict
;
46 with Rtsfind
; use Rtsfind
;
48 with Sem_Case
; use Sem_Case
;
49 with Sem_Cat
; use Sem_Cat
;
50 with Sem_Ch6
; use Sem_Ch6
;
51 with Sem_Ch7
; use Sem_Ch7
;
52 with Sem_Ch8
; use Sem_Ch8
;
53 with Sem_Ch13
; use Sem_Ch13
;
54 with Sem_Disp
; use Sem_Disp
;
55 with Sem_Dist
; use Sem_Dist
;
56 with Sem_Elim
; use Sem_Elim
;
57 with Sem_Eval
; use Sem_Eval
;
58 with Sem_Mech
; use Sem_Mech
;
59 with Sem_Res
; use Sem_Res
;
60 with Sem_Smem
; use Sem_Smem
;
61 with Sem_Type
; use Sem_Type
;
62 with Sem_Util
; use Sem_Util
;
63 with Sem_Warn
; use Sem_Warn
;
64 with Stand
; use Stand
;
65 with Sinfo
; use Sinfo
;
66 with Snames
; use Snames
;
67 with Tbuild
; use Tbuild
;
68 with Ttypes
; use Ttypes
;
69 with Uintp
; use Uintp
;
70 with Urealp
; use Urealp
;
72 package body Sem_Ch3
is
74 -----------------------
75 -- Local Subprograms --
76 -----------------------
78 procedure Build_Derived_Type
80 Parent_Type
: Entity_Id
;
81 Derived_Type
: Entity_Id
;
82 Is_Completion
: Boolean;
83 Derive_Subps
: Boolean := True);
84 -- Create and decorate a Derived_Type given the Parent_Type entity.
85 -- N is the N_Full_Type_Declaration node containing the derived type
86 -- definition. Parent_Type is the entity for the parent type in the derived
87 -- type definition and Derived_Type the actual derived type. Is_Completion
88 -- must be set to False if Derived_Type is the N_Defining_Identifier node
89 -- in N (ie Derived_Type = Defining_Identifier (N)). In this case N is not
90 -- the completion of a private type declaration. If Is_Completion is
91 -- set to True, N is the completion of a private type declaration and
92 -- Derived_Type is different from the defining identifier inside N (i.e.
93 -- Derived_Type /= Defining_Identifier (N)). Derive_Subps indicates whether
94 -- the parent subprograms should be derived. The only case where this
95 -- parameter is False is when Build_Derived_Type is recursively called to
96 -- process an implicit derived full type for a type derived from a private
97 -- type (in that case the subprograms must only be derived for the private
99 -- ??? These flags need a bit of re-examination and re-documentation:
100 -- ??? are they both necessary (both seem related to the recursion)?
102 procedure Build_Derived_Access_Type
104 Parent_Type
: Entity_Id
;
105 Derived_Type
: Entity_Id
);
106 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
107 -- create an implicit base if the parent type is constrained or if the
108 -- subtype indication has a constraint.
110 procedure Build_Derived_Array_Type
112 Parent_Type
: Entity_Id
;
113 Derived_Type
: Entity_Id
);
114 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
115 -- create an implicit base if the parent type is constrained or if the
116 -- subtype indication has a constraint.
118 procedure Build_Derived_Concurrent_Type
120 Parent_Type
: Entity_Id
;
121 Derived_Type
: Entity_Id
);
122 -- Subsidiary procedure to Build_Derived_Type. For a derived task or pro-
123 -- tected type, inherit entries and protected subprograms, check legality
124 -- of discriminant constraints if any.
126 procedure Build_Derived_Enumeration_Type
128 Parent_Type
: Entity_Id
;
129 Derived_Type
: Entity_Id
);
130 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
131 -- type, we must create a new list of literals. Types derived from
132 -- Character and Wide_Character are special-cased.
134 procedure Build_Derived_Numeric_Type
136 Parent_Type
: Entity_Id
;
137 Derived_Type
: Entity_Id
);
138 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
139 -- an anonymous base type, and propagate constraint to subtype if needed.
141 procedure Build_Derived_Private_Type
143 Parent_Type
: Entity_Id
;
144 Derived_Type
: Entity_Id
;
145 Is_Completion
: Boolean;
146 Derive_Subps
: Boolean := True);
147 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
148 -- because the parent may or may not have a completion, and the derivation
149 -- may itself be a completion.
151 procedure Build_Derived_Record_Type
153 Parent_Type
: Entity_Id
;
154 Derived_Type
: Entity_Id
;
155 Derive_Subps
: Boolean := True);
156 -- Subsidiary procedure to Build_Derived_Type and
157 -- Analyze_Private_Extension_Declaration used for tagged and untagged
158 -- record types. All parameters are as in Build_Derived_Type except that
159 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
160 -- N_Private_Extension_Declaration node. See the definition of this routine
161 -- for much more info. Derive_Subps indicates whether subprograms should
162 -- be derived from the parent type. The only case where Derive_Subps is
163 -- False is for an implicit derived full type for a type derived from a
164 -- private type (see Build_Derived_Type).
166 function Inherit_Components
168 Parent_Base
: Entity_Id
;
169 Derived_Base
: Entity_Id
;
171 Inherit_Discr
: Boolean;
172 Discs
: Elist_Id
) return Elist_Id
;
173 -- Called from Build_Derived_Record_Type to inherit the components of
174 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
175 -- For more information on derived types and component inheritance please
176 -- consult the comment above the body of Build_Derived_Record_Type.
178 -- N is the original derived type declaration.
180 -- Is_Tagged is set if we are dealing with tagged types.
182 -- If Inherit_Discr is set, Derived_Base inherits its discriminants
183 -- from Parent_Base, otherwise no discriminants are inherited.
185 -- Discs gives the list of constraints that apply to Parent_Base in the
186 -- derived type declaration. If Discs is set to No_Elist, then we have
187 -- the following situation:
189 -- type Parent (D1..Dn : ..) is [tagged] record ...;
190 -- type Derived is new Parent [with ...];
192 -- which gets treated as
194 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
196 -- For untagged types the returned value is an association list. The list
197 -- starts from the association (Parent_Base => Derived_Base), and then it
198 -- contains a sequence of the associations of the form
200 -- (Old_Component => New_Component),
202 -- where Old_Component is the Entity_Id of a component in Parent_Base
203 -- and New_Component is the Entity_Id of the corresponding component
204 -- in Derived_Base. For untagged records, this association list is
205 -- needed when copying the record declaration for the derived base.
206 -- In the tagged case the value returned is irrelevant.
208 procedure Build_Discriminal
(Discrim
: Entity_Id
);
209 -- Create the discriminal corresponding to discriminant Discrim, that is
210 -- the parameter corresponding to Discrim to be used in initialization
211 -- procedures for the type where Discrim is a discriminant. Discriminals
212 -- are not used during semantic analysis, and are not fully defined
213 -- entities until expansion. Thus they are not given a scope until
214 -- initialization procedures are built.
216 function Build_Discriminant_Constraints
219 Derived_Def
: Boolean := False) return Elist_Id
;
220 -- Validate discriminant constraints, and return the list of the
221 -- constraints in order of discriminant declarations. T is the
222 -- discriminated unconstrained type. Def is the N_Subtype_Indication
223 -- node where the discriminants constraints for T are specified.
224 -- Derived_Def is True if we are building the discriminant constraints
225 -- in a derived type definition of the form "type D (...) is new T (xxx)".
226 -- In this case T is the parent type and Def is the constraint "(xxx)" on
227 -- T and this routine sets the Corresponding_Discriminant field of the
228 -- discriminants in the derived type D to point to the corresponding
229 -- discriminants in the parent type T.
231 procedure Build_Discriminated_Subtype
235 Related_Nod
: Node_Id
;
236 For_Access
: Boolean := False);
237 -- Subsidiary procedure to Constrain_Discriminated_Type and to
238 -- Process_Incomplete_Dependents. Given
240 -- T (a possibly discriminated base type)
241 -- Def_Id (a very partially built subtype for T),
243 -- the call completes Def_Id to be the appropriate E_*_Subtype.
245 -- The Elist is the list of discriminant constraints if any (it is set to
246 -- No_Elist if T is not a discriminated type, and to an empty list if
247 -- T has discriminants but there are no discriminant constraints). The
248 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
249 -- The For_Access says whether or not this subtype is really constraining
250 -- an access type. That is its sole purpose is the designated type of an
251 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
252 -- is built to avoid freezing T when the access subtype is frozen.
254 function Build_Scalar_Bound
257 Der_T
: Entity_Id
) return Node_Id
;
258 -- The bounds of a derived scalar type are conversions of the bounds of
259 -- the parent type. Optimize the representation if the bounds are literals.
260 -- Needs a more complete spec--what are the parameters exactly, and what
261 -- exactly is the returned value, and how is Bound affected???
263 procedure Build_Underlying_Full_View
267 -- If the completion of a private type is itself derived from a private
268 -- type, or if the full view of a private subtype is itself private, the
269 -- back-end has no way to compute the actual size of this type. We build
270 -- an internal subtype declaration of the proper parent type to convey
271 -- this information. This extra mechanism is needed because a full
272 -- view cannot itself have a full view (it would get clobbered during
275 procedure Check_Access_Discriminant_Requires_Limited
278 -- Check the restriction that the type to which an access discriminant
279 -- belongs must be a concurrent type or a descendant of a type with
280 -- the reserved word 'limited' in its declaration.
282 procedure Check_Delta_Expression
(E
: Node_Id
);
283 -- Check that the expression represented by E is suitable for use
284 -- as a delta expression, i.e. it is of real type and is static.
286 procedure Check_Digits_Expression
(E
: Node_Id
);
287 -- Check that the expression represented by E is suitable for use as
288 -- a digits expression, i.e. it is of integer type, positive and static.
290 procedure Check_Initialization
(T
: Entity_Id
; Exp
: Node_Id
);
291 -- Validate the initialization of an object declaration. T is the
292 -- required type, and Exp is the initialization expression.
294 procedure Check_Or_Process_Discriminants
297 Prev
: Entity_Id
:= Empty
);
298 -- If T is the full declaration of an incomplete or private type, check
299 -- the conformance of the discriminants, otherwise process them. Prev
300 -- is the entity of the partial declaration, if any.
302 procedure Check_Real_Bound
(Bound
: Node_Id
);
303 -- Check given bound for being of real type and static. If not, post an
304 -- appropriate message, and rewrite the bound with the real literal zero.
306 procedure Constant_Redeclaration
310 -- Various checks on legality of full declaration of deferred constant.
311 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
312 -- node. The caller has not yet set any attributes of this entity.
314 procedure Convert_Scalar_Bounds
316 Parent_Type
: Entity_Id
;
317 Derived_Type
: Entity_Id
;
319 -- For derived scalar types, convert the bounds in the type definition
320 -- to the derived type, and complete their analysis. Given a constraint
322 -- .. new T range Lo .. Hi;
323 -- Lo and Hi are analyzed and resolved with T'Base, the parent_type.
324 -- The bounds of the derived type (the anonymous base) are copies of
325 -- Lo and Hi. Finally, the bounds of the derived subtype are conversions
326 -- of those bounds to the derived_type, so that their typing is
329 procedure Copy_Array_Base_Type_Attributes
(T1
, T2
: Entity_Id
);
330 -- Copies attributes from array base type T2 to array base type T1.
331 -- Copies only attributes that apply to base types, but not subtypes.
333 procedure Copy_Array_Subtype_Attributes
(T1
, T2
: Entity_Id
);
334 -- Copies attributes from array subtype T2 to array subtype T1. Copies
335 -- attributes that apply to both subtypes and base types.
337 procedure Create_Constrained_Components
341 Constraints
: Elist_Id
);
342 -- Build the list of entities for a constrained discriminated record
343 -- subtype. If a component depends on a discriminant, replace its subtype
344 -- using the discriminant values in the discriminant constraint.
345 -- Subt is the defining identifier for the subtype whose list of
346 -- constrained entities we will create. Decl_Node is the type declaration
347 -- node where we will attach all the itypes created. Typ is the base
348 -- discriminated type for the subtype Subt. Constraints is the list of
349 -- discriminant constraints for Typ.
351 function Constrain_Component_Type
352 (Compon_Type
: Entity_Id
;
353 Constrained_Typ
: Entity_Id
;
354 Related_Node
: Node_Id
;
356 Constraints
: Elist_Id
) return Entity_Id
;
357 -- Given a discriminated base type Typ, a list of discriminant constraint
358 -- Constraints for Typ and the type of a component of Typ, Compon_Type,
359 -- create and return the type corresponding to Compon_type where all
360 -- discriminant references are replaced with the corresponding
361 -- constraint. If no discriminant references occur in Compon_Typ then
362 -- return it as is. Constrained_Typ is the final constrained subtype to
363 -- which the constrained Compon_Type belongs. Related_Node is the node
364 -- where we will attach all the itypes created.
366 procedure Constrain_Access
367 (Def_Id
: in out Entity_Id
;
369 Related_Nod
: Node_Id
);
370 -- Apply a list of constraints to an access type. If Def_Id is empty,
371 -- it is an anonymous type created for a subtype indication. In that
372 -- case it is created in the procedure and attached to Related_Nod.
374 procedure Constrain_Array
375 (Def_Id
: in out Entity_Id
;
377 Related_Nod
: Node_Id
;
378 Related_Id
: Entity_Id
;
380 -- Apply a list of index constraints to an unconstrained array type. The
381 -- first parameter is the entity for the resulting subtype. A value of
382 -- Empty for Def_Id indicates that an implicit type must be created, but
383 -- creation is delayed (and must be done by this procedure) because other
384 -- subsidiary implicit types must be created first (which is why Def_Id
385 -- is an in/out parameter). The second parameter is a subtype indication
386 -- node for the constrained array to be created (e.g. something of the
387 -- form string (1 .. 10)). Related_Nod gives the place where this type
388 -- has to be inserted in the tree. The Related_Id and Suffix parameters
389 -- are used to build the associated Implicit type name.
391 procedure Constrain_Concurrent
392 (Def_Id
: in out Entity_Id
;
394 Related_Nod
: Node_Id
;
395 Related_Id
: Entity_Id
;
397 -- Apply list of discriminant constraints to an unconstrained concurrent
400 -- SI is the N_Subtype_Indication node containing the constraint and
401 -- the unconstrained type to constrain.
403 -- Def_Id is the entity for the resulting constrained subtype. A
404 -- value of Empty for Def_Id indicates that an implicit type must be
405 -- created, but creation is delayed (and must be done by this procedure)
406 -- because other subsidiary implicit types must be created first (which
407 -- is why Def_Id is an in/out parameter).
409 -- Related_Nod gives the place where this type has to be inserted
412 -- The last two arguments are used to create its external name if needed.
414 function Constrain_Corresponding_Record
415 (Prot_Subt
: Entity_Id
;
416 Corr_Rec
: Entity_Id
;
417 Related_Nod
: Node_Id
;
418 Related_Id
: Entity_Id
) return Entity_Id
;
419 -- When constraining a protected type or task type with discriminants,
420 -- constrain the corresponding record with the same discriminant values.
422 procedure Constrain_Decimal
(Def_Id
: Node_Id
; S
: Node_Id
);
423 -- Constrain a decimal fixed point type with a digits constraint and/or a
424 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
426 procedure Constrain_Discriminated_Type
429 Related_Nod
: Node_Id
;
430 For_Access
: Boolean := False);
431 -- Process discriminant constraints of composite type. Verify that values
432 -- have been provided for all discriminants, that the original type is
433 -- unconstrained, and that the types of the supplied expressions match
434 -- the discriminant types. The first three parameters are like in routine
435 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
438 procedure Constrain_Enumeration
(Def_Id
: Node_Id
; S
: Node_Id
);
439 -- Constrain an enumeration type with a range constraint. This is
440 -- identical to Constrain_Integer, but for the Ekind of the
441 -- resulting subtype.
443 procedure Constrain_Float
(Def_Id
: Node_Id
; S
: Node_Id
);
444 -- Constrain a floating point type with either a digits constraint
445 -- and/or a range constraint, building a E_Floating_Point_Subtype.
447 procedure Constrain_Index
450 Related_Nod
: Node_Id
;
451 Related_Id
: Entity_Id
;
454 -- Process an index constraint in a constrained array declaration.
455 -- The constraint can be a subtype name, or a range with or without
456 -- an explicit subtype mark. The index is the corresponding index of the
457 -- unconstrained array. The Related_Id and Suffix parameters are used to
458 -- build the associated Implicit type name.
460 procedure Constrain_Integer
(Def_Id
: Node_Id
; S
: Node_Id
);
461 -- Build subtype of a signed or modular integer type.
463 procedure Constrain_Ordinary_Fixed
(Def_Id
: Node_Id
; S
: Node_Id
);
464 -- Constrain an ordinary fixed point type with a range constraint, and
465 -- build an E_Ordinary_Fixed_Point_Subtype entity.
467 procedure Copy_And_Swap
(Priv
, Full
: Entity_Id
);
468 -- Copy the Priv entity into the entity of its full declaration
469 -- then swap the two entities in such a manner that the former private
470 -- type is now seen as a full type.
472 procedure Decimal_Fixed_Point_Type_Declaration
475 -- Create a new decimal fixed point type, and apply the constraint to
476 -- obtain a subtype of this new type.
478 procedure Complete_Private_Subtype
481 Full_Base
: Entity_Id
;
482 Related_Nod
: Node_Id
);
483 -- Complete the implicit full view of a private subtype by setting
484 -- the appropriate semantic fields. If the full view of the parent is
485 -- a record type, build constrained components of subtype.
487 procedure Derived_Standard_Character
489 Parent_Type
: Entity_Id
;
490 Derived_Type
: Entity_Id
);
491 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
492 -- derivations from types Standard.Character and Standard.Wide_Character.
494 procedure Derived_Type_Declaration
497 Is_Completion
: Boolean);
498 -- Process a derived type declaration. This routine will invoke
499 -- Build_Derived_Type to process the actual derived type definition.
500 -- Parameters N and Is_Completion have the same meaning as in
501 -- Build_Derived_Type. T is the N_Defining_Identifier for the entity
502 -- defined in the N_Full_Type_Declaration node N, that is T is the
505 function Find_Type_Of_Subtype_Indic
(S
: Node_Id
) return Entity_Id
;
506 -- Given a subtype indication S (which is really an N_Subtype_Indication
507 -- node or a plain N_Identifier), find the type of the subtype mark.
509 procedure Enumeration_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
);
510 -- Insert each literal in symbol table, as an overloadable identifier
511 -- Each enumeration type is mapped into a sequence of integers, and
512 -- each literal is defined as a constant with integer value. If any
513 -- of the literals are character literals, the type is a character
514 -- type, which means that strings are legal aggregates for arrays of
515 -- components of the type.
517 function Expand_To_Stored_Constraint
519 Constraint
: Elist_Id
) return Elist_Id
;
520 -- Given a Constraint (ie a list of expressions) on the discriminants of
521 -- Typ, expand it into a constraint on the stored discriminants and
522 -- return the new list of expressions constraining the stored
525 function Find_Type_Of_Object
527 Related_Nod
: Node_Id
) return Entity_Id
;
528 -- Get type entity for object referenced by Obj_Def, attaching the
529 -- implicit types generated to Related_Nod
531 procedure Floating_Point_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
);
532 -- Create a new float, and apply the constraint to obtain subtype of it
534 function Has_Range_Constraint
(N
: Node_Id
) return Boolean;
535 -- Given an N_Subtype_Indication node N, return True if a range constraint
536 -- is present, either directly, or as part of a digits or delta constraint.
537 -- In addition, a digits constraint in the decimal case returns True, since
538 -- it establishes a default range if no explicit range is present.
540 function Is_Valid_Constraint_Kind
542 Constraint_Kind
: Node_Kind
) return Boolean;
543 -- Returns True if it is legal to apply the given kind of constraint
544 -- to the given kind of type (index constraint to an array type,
547 procedure Modular_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
);
548 -- Create new modular type. Verify that modulus is in bounds and is
549 -- a power of two (implementation restriction).
551 procedure New_Concatenation_Op
(Typ
: Entity_Id
);
552 -- Create an abbreviated declaration for an operator in order to
553 -- materialize concatenation on array types.
555 procedure Ordinary_Fixed_Point_Type_Declaration
558 -- Create a new ordinary fixed point type, and apply the constraint
559 -- to obtain subtype of it.
561 procedure Prepare_Private_Subtype_Completion
563 Related_Nod
: Node_Id
);
564 -- Id is a subtype of some private type. Creates the full declaration
565 -- associated with Id whenever possible, i.e. when the full declaration
566 -- of the base type is already known. Records each subtype into
567 -- Private_Dependents of the base type.
569 procedure Process_Incomplete_Dependents
573 -- Process all entities that depend on an incomplete type. There include
574 -- subtypes, subprogram types that mention the incomplete type in their
575 -- profiles, and subprogram with access parameters that designate the
578 -- Inc_T is the defining identifier of an incomplete type declaration, its
579 -- Ekind is E_Incomplete_Type.
581 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
583 -- Full_T is N's defining identifier.
585 -- Subtypes of incomplete types with discriminants are completed when the
586 -- parent type is. This is simpler than private subtypes, because they can
587 -- only appear in the same scope, and there is no need to exchange views.
588 -- Similarly, access_to_subprogram types may have a parameter or a return
589 -- type that is an incomplete type, and that must be replaced with the
592 -- If the full type is tagged, subprogram with access parameters that
593 -- designated the incomplete may be primitive operations of the full type,
594 -- and have to be processed accordingly.
596 procedure Process_Real_Range_Specification
(Def
: Node_Id
);
597 -- Given the type definition for a real type, this procedure processes
598 -- and checks the real range specification of this type definition if
599 -- one is present. If errors are found, error messages are posted, and
600 -- the Real_Range_Specification of Def is reset to Empty.
602 procedure Record_Type_Declaration
606 -- Process a record type declaration (for both untagged and tagged
607 -- records). Parameters T and N are exactly like in procedure
608 -- Derived_Type_Declaration, except that no flag Is_Completion is
609 -- needed for this routine. If this is the completion of an incomplete
610 -- type declaration, Prev is the entity of the incomplete declaration,
611 -- used for cross-referencing. Otherwise Prev = T.
613 procedure Record_Type_Definition
(Def
: Node_Id
; Prev_T
: Entity_Id
);
614 -- This routine is used to process the actual record type definition
615 -- (both for untagged and tagged records). Def is a record type
616 -- definition node. This procedure analyzes the components in this
617 -- record type definition. Prev_T is the entity for the enclosing record
618 -- type. It is provided so that its Has_Task flag can be set if any of
619 -- the component have Has_Task set. If the declaration is the completion
620 -- of an incomplete type declaration, Prev_T is the original incomplete
621 -- type, whose full view is the record type.
623 procedure Replace_Components
(Typ
: Entity_Id
; Decl
: Node_Id
);
624 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
625 -- build a copy of the declaration tree of the parent, and we create
626 -- independently the list of components for the derived type. Semantic
627 -- information uses the component entities, but record representation
628 -- clauses are validated on the declaration tree. This procedure replaces
629 -- discriminants and components in the declaration with those that have
630 -- been created by Inherit_Components.
632 procedure Set_Fixed_Range
637 -- Build a range node with the given bounds and set it as the Scalar_Range
638 -- of the given fixed-point type entity. Loc is the source location used
639 -- for the constructed range. See body for further details.
641 procedure Set_Scalar_Range_For_Subtype
645 -- This routine is used to set the scalar range field for a subtype
646 -- given Def_Id, the entity for the subtype, and R, the range expression
647 -- for the scalar range. Subt provides the parent subtype to be used
648 -- to analyze, resolve, and check the given range.
650 procedure Signed_Integer_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
);
651 -- Create a new signed integer entity, and apply the constraint to obtain
652 -- the required first named subtype of this type.
654 procedure Set_Stored_Constraint_From_Discriminant_Constraint
656 -- E is some record type. This routine computes E's Stored_Constraint
657 -- from its Discriminant_Constraint.
659 -----------------------
660 -- Access_Definition --
661 -----------------------
663 function Access_Definition
664 (Related_Nod
: Node_Id
;
665 N
: Node_Id
) return Entity_Id
667 Anon_Type
: constant Entity_Id
:=
668 Create_Itype
(E_Anonymous_Access_Type
, Related_Nod
,
669 Scope_Id
=> Scope
(Current_Scope
));
670 Desig_Type
: Entity_Id
;
673 if Is_Entry
(Current_Scope
)
674 and then Is_Task_Type
(Etype
(Scope
(Current_Scope
)))
676 Error_Msg_N
("task entries cannot have access parameters", N
);
679 Find_Type
(Subtype_Mark
(N
));
680 Desig_Type
:= Entity
(Subtype_Mark
(N
));
682 Set_Directly_Designated_Type
683 (Anon_Type
, Desig_Type
);
684 Set_Etype
(Anon_Type
, Anon_Type
);
685 Init_Size_Align
(Anon_Type
);
686 Set_Depends_On_Private
(Anon_Type
, Has_Private_Component
(Anon_Type
));
688 -- The anonymous access type is as public as the discriminated type or
689 -- subprogram that defines it. It is imported (for back-end purposes)
690 -- if the designated type is.
692 Set_Is_Public
(Anon_Type
, Is_Public
(Scope
(Anon_Type
)));
694 -- Ada0Y (AI-50217): Propagate the attribute that indicates that the
695 -- designated type comes from the limited view (for back-end purposes).
697 Set_From_With_Type
(Anon_Type
, From_With_Type
(Desig_Type
));
699 -- The context is either a subprogram declaration or an access
700 -- discriminant, in a private or a full type declaration. In
701 -- the case of a subprogram, If the designated type is incomplete,
702 -- the operation will be a primitive operation of the full type, to
703 -- be updated subsequently.
705 if Ekind
(Desig_Type
) = E_Incomplete_Type
706 and then Is_Overloadable
(Current_Scope
)
708 Append_Elmt
(Current_Scope
, Private_Dependents
(Desig_Type
));
709 Set_Has_Delayed_Freeze
(Current_Scope
);
713 end Access_Definition
;
715 -----------------------------------
716 -- Access_Subprogram_Declaration --
717 -----------------------------------
719 procedure Access_Subprogram_Declaration
723 Formals
: constant List_Id
:= Parameter_Specifications
(T_Def
);
726 Desig_Type
: constant Entity_Id
:=
727 Create_Itype
(E_Subprogram_Type
, Parent
(T_Def
));
730 if Nkind
(T_Def
) = N_Access_Function_Definition
then
731 Analyze
(Subtype_Mark
(T_Def
));
732 Set_Etype
(Desig_Type
, Entity
(Subtype_Mark
(T_Def
)));
734 if not (Is_Type
(Etype
(Desig_Type
))) then
736 ("expect type in function specification", Subtype_Mark
(T_Def
));
740 Set_Etype
(Desig_Type
, Standard_Void_Type
);
743 if Present
(Formals
) then
744 New_Scope
(Desig_Type
);
745 Process_Formals
(Formals
, Parent
(T_Def
));
747 -- A bit of a kludge here, End_Scope requires that the parent
748 -- pointer be set to something reasonable, but Itypes don't
749 -- have parent pointers. So we set it and then unset it ???
750 -- If and when Itypes have proper parent pointers to their
751 -- declarations, this kludge can be removed.
753 Set_Parent
(Desig_Type
, T_Name
);
755 Set_Parent
(Desig_Type
, Empty
);
758 -- The return type and/or any parameter type may be incomplete. Mark
759 -- the subprogram_type as depending on the incomplete type, so that
760 -- it can be updated when the full type declaration is seen.
762 if Present
(Formals
) then
763 Formal
:= First_Formal
(Desig_Type
);
765 while Present
(Formal
) loop
767 if Ekind
(Formal
) /= E_In_Parameter
768 and then Nkind
(T_Def
) = N_Access_Function_Definition
770 Error_Msg_N
("functions can only have IN parameters", Formal
);
773 if Ekind
(Etype
(Formal
)) = E_Incomplete_Type
then
774 Append_Elmt
(Desig_Type
, Private_Dependents
(Etype
(Formal
)));
775 Set_Has_Delayed_Freeze
(Desig_Type
);
778 Next_Formal
(Formal
);
782 if Ekind
(Etype
(Desig_Type
)) = E_Incomplete_Type
783 and then not Has_Delayed_Freeze
(Desig_Type
)
785 Append_Elmt
(Desig_Type
, Private_Dependents
(Etype
(Desig_Type
)));
786 Set_Has_Delayed_Freeze
(Desig_Type
);
789 Check_Delayed_Subprogram
(Desig_Type
);
791 if Protected_Present
(T_Def
) then
792 Set_Ekind
(T_Name
, E_Access_Protected_Subprogram_Type
);
793 Set_Convention
(Desig_Type
, Convention_Protected
);
795 Set_Ekind
(T_Name
, E_Access_Subprogram_Type
);
798 Set_Etype
(T_Name
, T_Name
);
799 Init_Size_Align
(T_Name
);
800 Set_Directly_Designated_Type
(T_Name
, Desig_Type
);
802 Check_Restriction
(No_Access_Subprograms
, T_Def
);
803 end Access_Subprogram_Declaration
;
805 ----------------------------
806 -- Access_Type_Declaration --
807 ----------------------------
809 procedure Access_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
) is
810 S
: constant Node_Id
:= Subtype_Indication
(Def
);
811 P
: constant Node_Id
:= Parent
(Def
);
817 -- Non-limited view, when needed
820 -- Check for permissible use of incomplete type
822 if Nkind
(S
) /= N_Subtype_Indication
then
825 if Ekind
(Root_Type
(Entity
(S
))) = E_Incomplete_Type
then
826 Set_Directly_Designated_Type
(T
, Entity
(S
));
828 Set_Directly_Designated_Type
(T
,
829 Process_Subtype
(S
, P
, T
, 'P'));
833 Set_Directly_Designated_Type
(T
,
834 Process_Subtype
(S
, P
, T
, 'P'));
837 if All_Present
(Def
) or Constant_Present
(Def
) then
838 Set_Ekind
(T
, E_General_Access_Type
);
840 Set_Ekind
(T
, E_Access_Type
);
843 if Base_Type
(Designated_Type
(T
)) = T
then
844 Error_Msg_N
("access type cannot designate itself", S
);
849 -- If the type has appeared already in a with_type clause, it is
850 -- frozen and the pointer size is already set. Else, initialize.
852 if not From_With_Type
(T
) then
856 Set_Is_Access_Constant
(T
, Constant_Present
(Def
));
858 Desig
:= Designated_Type
(T
);
860 -- If designated type is an imported tagged type, indicate that the
861 -- access type is also imported, and therefore restricted in its use.
862 -- The access type may already be imported, so keep setting otherwise.
864 -- Ada0Y (AI-50217): If the non-limited view of the designated type is
865 -- available, use it as the designated type of the access type, so that
866 -- the back-end gets a usable entity.
868 if From_With_Type
(Desig
) then
869 Set_From_With_Type
(T
);
871 if Ekind
(Desig
) = E_Incomplete_Type
then
872 N_Desig
:= Non_Limited_View
(Desig
);
874 elsif Ekind
(Desig
) = E_Class_Wide_Type
then
875 if From_With_Type
(Etype
(Desig
)) then
876 N_Desig
:= Non_Limited_View
(Etype
(Desig
));
878 N_Desig
:= Etype
(Desig
);
882 pragma Assert
(False);
885 pragma Assert
(Present
(N_Desig
));
886 Set_Directly_Designated_Type
(T
, N_Desig
);
889 -- Note that Has_Task is always false, since the access type itself
890 -- is not a task type. See Einfo for more description on this point.
891 -- Exactly the same consideration applies to Has_Controlled_Component.
893 Set_Has_Task
(T
, False);
894 Set_Has_Controlled_Component
(T
, False);
895 end Access_Type_Declaration
;
897 -----------------------------------
898 -- Analyze_Component_Declaration --
899 -----------------------------------
901 procedure Analyze_Component_Declaration
(N
: Node_Id
) is
902 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
907 Generate_Definition
(Id
);
909 T
:= Find_Type_Of_Object
(Subtype_Indication
(N
), N
);
911 -- If the subtype is a constrained subtype of the enclosing record,
912 -- (which must have a partial view) the back-end does not handle
913 -- properly the recursion. Rewrite the component declaration with
914 -- an explicit subtype indication, which is acceptable to Gigi. We
915 -- can copy the tree directly because side effects have already been
916 -- removed from discriminant constraints.
918 if Ekind
(T
) = E_Access_Subtype
919 and then Is_Entity_Name
(Subtype_Indication
(N
))
920 and then Comes_From_Source
(T
)
921 and then Nkind
(Parent
(T
)) = N_Subtype_Declaration
922 and then Etype
(Directly_Designated_Type
(T
)) = Current_Scope
925 (Subtype_Indication
(N
),
926 New_Copy_Tree
(Subtype_Indication
(Parent
(T
))));
927 T
:= Find_Type_Of_Object
(Subtype_Indication
(N
), N
);
930 -- If the component declaration includes a default expression, then we
931 -- check that the component is not of a limited type (RM 3.7(5)),
932 -- and do the special preanalysis of the expression (see section on
933 -- "Handling of Default and Per-Object Expressions" in the spec of
936 if Present
(Expression
(N
)) then
937 Analyze_Per_Use_Expression
(Expression
(N
), T
);
938 Check_Initialization
(T
, Expression
(N
));
941 -- The parent type may be a private view with unknown discriminants,
942 -- and thus unconstrained. Regular components must be constrained.
944 if Is_Indefinite_Subtype
(T
) and then Chars
(Id
) /= Name_uParent
then
946 ("unconstrained subtype in component declaration",
947 Subtype_Indication
(N
));
949 -- Components cannot be abstract, except for the special case of
950 -- the _Parent field (case of extending an abstract tagged type)
952 elsif Is_Abstract
(T
) and then Chars
(Id
) /= Name_uParent
then
953 Error_Msg_N
("type of a component cannot be abstract", N
);
957 Set_Is_Aliased
(Id
, Aliased_Present
(N
));
959 -- If the this component is private (or depends on a private type),
960 -- flag the record type to indicate that some operations are not
963 P
:= Private_Component
(T
);
966 -- Check for circular definitions.
969 Set_Etype
(Id
, Any_Type
);
971 -- There is a gap in the visibility of operations only if the
972 -- component type is not defined in the scope of the record type.
974 elsif Scope
(P
) = Scope
(Current_Scope
) then
977 elsif Is_Limited_Type
(P
) then
978 Set_Is_Limited_Composite
(Current_Scope
);
981 Set_Is_Private_Composite
(Current_Scope
);
986 and then Is_Limited_Type
(T
)
987 and then Chars
(Id
) /= Name_uParent
988 and then Is_Tagged_Type
(Current_Scope
)
990 if Is_Derived_Type
(Current_Scope
)
991 and then not Is_Limited_Record
(Root_Type
(Current_Scope
))
994 ("extension of nonlimited type cannot have limited components",
996 Explain_Limited_Type
(T
, N
);
997 Set_Etype
(Id
, Any_Type
);
998 Set_Is_Limited_Composite
(Current_Scope
, False);
1000 elsif not Is_Derived_Type
(Current_Scope
)
1001 and then not Is_Limited_Record
(Current_Scope
)
1004 ("nonlimited tagged type cannot have limited components", N
);
1005 Explain_Limited_Type
(T
, N
);
1006 Set_Etype
(Id
, Any_Type
);
1007 Set_Is_Limited_Composite
(Current_Scope
, False);
1011 Set_Original_Record_Component
(Id
, Id
);
1012 end Analyze_Component_Declaration
;
1014 --------------------------
1015 -- Analyze_Declarations --
1016 --------------------------
1018 procedure Analyze_Declarations
(L
: List_Id
) is
1020 Next_Node
: Node_Id
;
1021 Freeze_From
: Entity_Id
:= Empty
;
1024 -- Adjust D not to include implicit label declarations, since these
1025 -- have strange Sloc values that result in elaboration check problems.
1026 -- (They have the sloc of the label as found in the source, and that
1027 -- is ahead of the current declarative part).
1033 procedure Adjust_D
is
1035 while Present
(Prev
(D
))
1036 and then Nkind
(D
) = N_Implicit_Label_Declaration
1042 -- Start of processing for Analyze_Declarations
1046 while Present
(D
) loop
1048 -- Complete analysis of declaration
1051 Next_Node
:= Next
(D
);
1053 if No
(Freeze_From
) then
1054 Freeze_From
:= First_Entity
(Current_Scope
);
1057 -- At the end of a declarative part, freeze remaining entities
1058 -- declared in it. The end of the visible declarations of a
1059 -- package specification is not the end of a declarative part
1060 -- if private declarations are present. The end of a package
1061 -- declaration is a freezing point only if it a library package.
1062 -- A task definition or protected type definition is not a freeze
1063 -- point either. Finally, we do not freeze entities in generic
1064 -- scopes, because there is no code generated for them and freeze
1065 -- nodes will be generated for the instance.
1067 -- The end of a package instantiation is not a freeze point, but
1068 -- for now we make it one, because the generic body is inserted
1069 -- (currently) immediately after. Generic instantiations will not
1070 -- be a freeze point once delayed freezing of bodies is implemented.
1071 -- (This is needed in any case for early instantiations ???).
1073 if No
(Next_Node
) then
1074 if Nkind
(Parent
(L
)) = N_Component_List
1075 or else Nkind
(Parent
(L
)) = N_Task_Definition
1076 or else Nkind
(Parent
(L
)) = N_Protected_Definition
1080 elsif Nkind
(Parent
(L
)) /= N_Package_Specification
then
1081 if Nkind
(Parent
(L
)) = N_Package_Body
then
1082 Freeze_From
:= First_Entity
(Current_Scope
);
1086 Freeze_All
(Freeze_From
, D
);
1087 Freeze_From
:= Last_Entity
(Current_Scope
);
1089 elsif Scope
(Current_Scope
) /= Standard_Standard
1090 and then not Is_Child_Unit
(Current_Scope
)
1091 and then No
(Generic_Parent
(Parent
(L
)))
1095 elsif L
/= Visible_Declarations
(Parent
(L
))
1096 or else No
(Private_Declarations
(Parent
(L
)))
1097 or else Is_Empty_List
(Private_Declarations
(Parent
(L
)))
1100 Freeze_All
(Freeze_From
, D
);
1101 Freeze_From
:= Last_Entity
(Current_Scope
);
1104 -- If next node is a body then freeze all types before the body.
1105 -- An exception occurs for expander generated bodies, which can
1106 -- be recognized by their already being analyzed. The expander
1107 -- ensures that all types needed by these bodies have been frozen
1108 -- but it is not necessary to freeze all types (and would be wrong
1109 -- since it would not correspond to an RM defined freeze point).
1111 elsif not Analyzed
(Next_Node
)
1112 and then (Nkind
(Next_Node
) = N_Subprogram_Body
1113 or else Nkind
(Next_Node
) = N_Entry_Body
1114 or else Nkind
(Next_Node
) = N_Package_Body
1115 or else Nkind
(Next_Node
) = N_Protected_Body
1116 or else Nkind
(Next_Node
) = N_Task_Body
1117 or else Nkind
(Next_Node
) in N_Body_Stub
)
1120 Freeze_All
(Freeze_From
, D
);
1121 Freeze_From
:= Last_Entity
(Current_Scope
);
1126 end Analyze_Declarations
;
1128 ----------------------------------
1129 -- Analyze_Incomplete_Type_Decl --
1130 ----------------------------------
1132 procedure Analyze_Incomplete_Type_Decl
(N
: Node_Id
) is
1133 F
: constant Boolean := Is_Pure
(Current_Scope
);
1137 Generate_Definition
(Defining_Identifier
(N
));
1139 -- Process an incomplete declaration. The identifier must not have been
1140 -- declared already in the scope. However, an incomplete declaration may
1141 -- appear in the private part of a package, for a private type that has
1142 -- already been declared.
1144 -- In this case, the discriminants (if any) must match.
1146 T
:= Find_Type_Name
(N
);
1148 Set_Ekind
(T
, E_Incomplete_Type
);
1149 Init_Size_Align
(T
);
1150 Set_Is_First_Subtype
(T
, True);
1154 Set_Stored_Constraint
(T
, No_Elist
);
1156 if Present
(Discriminant_Specifications
(N
)) then
1157 Process_Discriminants
(N
);
1162 -- If the type has discriminants, non-trivial subtypes may be
1163 -- be declared before the full view of the type. The full views
1164 -- of those subtypes will be built after the full view of the type.
1166 Set_Private_Dependents
(T
, New_Elmt_List
);
1168 end Analyze_Incomplete_Type_Decl
;
1170 -----------------------------
1171 -- Analyze_Itype_Reference --
1172 -----------------------------
1174 -- Nothing to do. This node is placed in the tree only for the benefit
1175 -- of Gigi processing, and has no effect on the semantic processing.
1177 procedure Analyze_Itype_Reference
(N
: Node_Id
) is
1179 pragma Assert
(Is_Itype
(Itype
(N
)));
1181 end Analyze_Itype_Reference
;
1183 --------------------------------
1184 -- Analyze_Number_Declaration --
1185 --------------------------------
1187 procedure Analyze_Number_Declaration
(N
: Node_Id
) is
1188 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
1189 E
: constant Node_Id
:= Expression
(N
);
1191 Index
: Interp_Index
;
1195 Generate_Definition
(Id
);
1198 -- This is an optimization of a common case of an integer literal
1200 if Nkind
(E
) = N_Integer_Literal
then
1201 Set_Is_Static_Expression
(E
, True);
1202 Set_Etype
(E
, Universal_Integer
);
1204 Set_Etype
(Id
, Universal_Integer
);
1205 Set_Ekind
(Id
, E_Named_Integer
);
1206 Set_Is_Frozen
(Id
, True);
1210 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
1212 -- Process expression, replacing error by integer zero, to avoid
1213 -- cascaded errors or aborts further along in the processing
1215 -- Replace Error by integer zero, which seems least likely to
1216 -- cause cascaded errors.
1219 Rewrite
(E
, Make_Integer_Literal
(Sloc
(E
), Uint_0
));
1220 Set_Error_Posted
(E
);
1225 -- Verify that the expression is static and numeric. If
1226 -- the expression is overloaded, we apply the preference
1227 -- rule that favors root numeric types.
1229 if not Is_Overloaded
(E
) then
1234 Get_First_Interp
(E
, Index
, It
);
1236 while Present
(It
.Typ
) loop
1237 if (Is_Integer_Type
(It
.Typ
)
1238 or else Is_Real_Type
(It
.Typ
))
1239 and then (Scope
(Base_Type
(It
.Typ
))) = Standard_Standard
1241 if T
= Any_Type
then
1244 elsif It
.Typ
= Universal_Real
1245 or else It
.Typ
= Universal_Integer
1247 -- Choose universal interpretation over any other.
1254 Get_Next_Interp
(Index
, It
);
1258 if Is_Integer_Type
(T
) then
1260 Set_Etype
(Id
, Universal_Integer
);
1261 Set_Ekind
(Id
, E_Named_Integer
);
1263 elsif Is_Real_Type
(T
) then
1265 -- Because the real value is converted to universal_real, this
1266 -- is a legal context for a universal fixed expression.
1268 if T
= Universal_Fixed
then
1270 Loc
: constant Source_Ptr
:= Sloc
(N
);
1271 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
1273 New_Occurrence_Of
(Universal_Real
, Loc
),
1274 Expression
=> Relocate_Node
(E
));
1281 elsif T
= Any_Fixed
then
1282 Error_Msg_N
("illegal context for mixed mode operation", E
);
1284 -- Expression is of the form : universal_fixed * integer.
1285 -- Try to resolve as universal_real.
1287 T
:= Universal_Real
;
1292 Set_Etype
(Id
, Universal_Real
);
1293 Set_Ekind
(Id
, E_Named_Real
);
1296 Wrong_Type
(E
, Any_Numeric
);
1300 Set_Ekind
(Id
, E_Constant
);
1301 Set_Never_Set_In_Source
(Id
, True);
1302 Set_Is_True_Constant
(Id
, True);
1306 if Nkind
(E
) = N_Integer_Literal
1307 or else Nkind
(E
) = N_Real_Literal
1309 Set_Etype
(E
, Etype
(Id
));
1312 if not Is_OK_Static_Expression
(E
) then
1313 Flag_Non_Static_Expr
1314 ("non-static expression used in number declaration!", E
);
1315 Rewrite
(E
, Make_Integer_Literal
(Sloc
(N
), 1));
1316 Set_Etype
(E
, Any_Type
);
1318 end Analyze_Number_Declaration
;
1320 --------------------------------
1321 -- Analyze_Object_Declaration --
1322 --------------------------------
1324 procedure Analyze_Object_Declaration
(N
: Node_Id
) is
1325 Loc
: constant Source_Ptr
:= Sloc
(N
);
1326 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
1330 E
: Node_Id
:= Expression
(N
);
1331 -- E is set to Expression (N) throughout this routine. When
1332 -- Expression (N) is modified, E is changed accordingly.
1334 Prev_Entity
: Entity_Id
:= Empty
;
1336 function Build_Default_Subtype
return Entity_Id
;
1337 -- If the object is limited or aliased, and if the type is unconstrained
1338 -- and there is no expression, the discriminants cannot be modified and
1339 -- the subtype of the object is constrained by the defaults, so it is
1340 -- worthile building the corresponding subtype.
1342 ---------------------------
1343 -- Build_Default_Subtype --
1344 ---------------------------
1346 function Build_Default_Subtype
return Entity_Id
is
1347 Constraints
: constant List_Id
:= New_List
;
1353 Disc
:= First_Discriminant
(T
);
1355 if No
(Discriminant_Default_Value
(Disc
)) then
1356 return T
; -- previous error.
1359 Act
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('S'));
1360 while Present
(Disc
) loop
1363 Discriminant_Default_Value
(Disc
)), Constraints
);
1364 Next_Discriminant
(Disc
);
1368 Make_Subtype_Declaration
(Loc
,
1369 Defining_Identifier
=> Act
,
1370 Subtype_Indication
=>
1371 Make_Subtype_Indication
(Loc
,
1372 Subtype_Mark
=> New_Occurrence_Of
(T
, Loc
),
1374 Make_Index_Or_Discriminant_Constraint
1375 (Loc
, Constraints
)));
1377 Insert_Before
(N
, Decl
);
1380 end Build_Default_Subtype
;
1382 -- Start of processing for Analyze_Object_Declaration
1385 -- There are three kinds of implicit types generated by an
1386 -- object declaration:
1388 -- 1. Those for generated by the original Object Definition
1390 -- 2. Those generated by the Expression
1392 -- 3. Those used to constrained the Object Definition with the
1393 -- expression constraints when it is unconstrained
1395 -- They must be generated in this order to avoid order of elaboration
1396 -- issues. Thus the first step (after entering the name) is to analyze
1397 -- the object definition.
1399 if Constant_Present
(N
) then
1400 Prev_Entity
:= Current_Entity_In_Scope
(Id
);
1402 -- If homograph is an implicit subprogram, it is overridden by the
1403 -- current declaration.
1405 if Present
(Prev_Entity
)
1406 and then Is_Overloadable
(Prev_Entity
)
1407 and then Is_Inherited_Operation
(Prev_Entity
)
1409 Prev_Entity
:= Empty
;
1413 if Present
(Prev_Entity
) then
1414 Constant_Redeclaration
(Id
, N
, T
);
1416 Generate_Reference
(Prev_Entity
, Id
, 'c');
1417 Set_Completion_Referenced
(Id
);
1419 if Error_Posted
(N
) then
1420 -- Type mismatch or illegal redeclaration, Do not analyze
1421 -- expression to avoid cascaded errors.
1423 T
:= Find_Type_Of_Object
(Object_Definition
(N
), N
);
1425 Set_Ekind
(Id
, E_Variable
);
1429 -- In the normal case, enter identifier at the start to catch
1430 -- premature usage in the initialization expression.
1433 Generate_Definition
(Id
);
1436 T
:= Find_Type_Of_Object
(Object_Definition
(N
), N
);
1438 if Error_Posted
(Id
) then
1440 Set_Ekind
(Id
, E_Variable
);
1445 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
1447 -- If deferred constant, make sure context is appropriate. We detect
1448 -- a deferred constant as a constant declaration with no expression.
1449 -- A deferred constant can appear in a package body if its completion
1450 -- is by means of an interface pragma.
1452 if Constant_Present
(N
)
1455 if not Is_Package
(Current_Scope
) then
1457 ("invalid context for deferred constant declaration ('R'M 7.4)",
1460 ("\declaration requires an initialization expression",
1462 Set_Constant_Present
(N
, False);
1464 -- In Ada 83, deferred constant must be of private type
1466 elsif not Is_Private_Type
(T
) then
1467 if Ada_83
and then Comes_From_Source
(N
) then
1469 ("(Ada 83) deferred constant must be private type", N
);
1473 -- If not a deferred constant, then object declaration freezes its type
1476 Check_Fully_Declared
(T
, N
);
1477 Freeze_Before
(N
, T
);
1480 -- If the object was created by a constrained array definition, then
1481 -- set the link in both the anonymous base type and anonymous subtype
1482 -- that are built to represent the array type to point to the object.
1484 if Nkind
(Object_Definition
(Declaration_Node
(Id
))) =
1485 N_Constrained_Array_Definition
1487 Set_Related_Array_Object
(T
, Id
);
1488 Set_Related_Array_Object
(Base_Type
(T
), Id
);
1491 -- Special checks for protected objects not at library level
1493 if Is_Protected_Type
(T
)
1494 and then not Is_Library_Level_Entity
(Id
)
1496 Check_Restriction
(No_Local_Protected_Objects
, Id
);
1498 -- Protected objects with interrupt handlers must be at library level
1500 if Has_Interrupt_Handler
(T
) then
1502 ("interrupt object can only be declared at library level", Id
);
1506 -- The actual subtype of the object is the nominal subtype, unless
1507 -- the nominal one is unconstrained and obtained from the expression.
1511 -- Process initialization expression if present and not in error
1513 if Present
(E
) and then E
/= Error
then
1516 -- If an initialization expression is present, then we set the
1517 -- Is_True_Constant flag. It will be reset if this is a variable
1518 -- and it is indeed modified.
1520 Set_Is_True_Constant
(Id
, True);
1522 if not Assignment_OK
(N
) then
1523 Check_Initialization
(T
, E
);
1526 Set_Etype
(Id
, T
); -- may be overridden later on.
1528 Check_Unset_Reference
(E
);
1530 if Compile_Time_Known_Value
(E
) then
1531 Set_Current_Value
(Id
, E
);
1534 -- Check incorrect use of dynamically tagged expressions. Note
1535 -- the use of Is_Tagged_Type (T) which seems redundant but is in
1536 -- fact important to avoid spurious errors due to expanded code
1537 -- for dispatching functions over an anonymous access type
1539 if (Is_Class_Wide_Type
(Etype
(E
)) or else Is_Dynamically_Tagged
(E
))
1540 and then Is_Tagged_Type
(T
)
1541 and then not Is_Class_Wide_Type
(T
)
1543 Error_Msg_N
("dynamically tagged expression not allowed!", E
);
1546 Apply_Scalar_Range_Check
(E
, T
);
1547 Apply_Static_Length_Check
(E
, T
);
1550 -- Abstract type is never permitted for a variable or constant.
1551 -- Note: we inhibit this check for objects that do not come from
1552 -- source because there is at least one case (the expansion of
1553 -- x'class'input where x is abstract) where we legitimately
1554 -- generate an abstract object.
1556 if Is_Abstract
(T
) and then Comes_From_Source
(N
) then
1557 Error_Msg_N
("type of object cannot be abstract",
1558 Object_Definition
(N
));
1559 if Is_CPP_Class
(T
) then
1560 Error_Msg_NE
("\} may need a cpp_constructor",
1561 Object_Definition
(N
), T
);
1564 -- Case of unconstrained type
1566 elsif Is_Indefinite_Subtype
(T
) then
1568 -- Nothing to do in deferred constant case
1570 if Constant_Present
(N
) and then No
(E
) then
1573 -- Case of no initialization present
1576 if No_Initialization
(N
) then
1579 elsif Is_Class_Wide_Type
(T
) then
1581 ("initialization required in class-wide declaration ", N
);
1585 ("unconstrained subtype not allowed (need initialization)",
1586 Object_Definition
(N
));
1589 -- Case of initialization present but in error. Set initial
1590 -- expression as absent (but do not make above complaints)
1592 elsif E
= Error
then
1593 Set_Expression
(N
, Empty
);
1596 -- Case of initialization present
1599 -- Not allowed in Ada 83
1601 if not Constant_Present
(N
) then
1603 and then Comes_From_Source
(Object_Definition
(N
))
1606 ("(Ada 83) unconstrained variable not allowed",
1607 Object_Definition
(N
));
1611 -- Now we constrain the variable from the initializing expression
1613 -- If the expression is an aggregate, it has been expanded into
1614 -- individual assignments. Retrieve the actual type from the
1615 -- expanded construct.
1617 if Is_Array_Type
(T
)
1618 and then No_Initialization
(N
)
1619 and then Nkind
(Original_Node
(E
)) = N_Aggregate
1624 Expand_Subtype_From_Expr
(N
, T
, Object_Definition
(N
), E
);
1625 Act_T
:= Find_Type_Of_Object
(Object_Definition
(N
), N
);
1628 Set_Is_Constr_Subt_For_U_Nominal
(Act_T
);
1630 if Aliased_Present
(N
) then
1631 Set_Is_Constr_Subt_For_UN_Aliased
(Act_T
);
1634 Freeze_Before
(N
, Act_T
);
1635 Freeze_Before
(N
, T
);
1638 elsif Is_Array_Type
(T
)
1639 and then No_Initialization
(N
)
1640 and then Nkind
(Original_Node
(E
)) = N_Aggregate
1642 if not Is_Entity_Name
(Object_Definition
(N
)) then
1644 Check_Compile_Time_Size
(Act_T
);
1646 if Aliased_Present
(N
) then
1647 Set_Is_Constr_Subt_For_UN_Aliased
(Act_T
);
1651 -- When the given object definition and the aggregate are specified
1652 -- independently, and their lengths might differ do a length check.
1653 -- This cannot happen if the aggregate is of the form (others =>...)
1655 if not Is_Constrained
(T
) then
1658 elsif Nkind
(E
) = N_Raise_Constraint_Error
then
1660 -- Aggregate is statically illegal. Place back in declaration
1662 Set_Expression
(N
, E
);
1663 Set_No_Initialization
(N
, False);
1665 elsif T
= Etype
(E
) then
1668 elsif Nkind
(E
) = N_Aggregate
1669 and then Present
(Component_Associations
(E
))
1670 and then Present
(Choices
(First
(Component_Associations
(E
))))
1671 and then Nkind
(First
1672 (Choices
(First
(Component_Associations
(E
))))) = N_Others_Choice
1677 Apply_Length_Check
(E
, T
);
1680 elsif (Is_Limited_Record
(T
)
1681 or else Is_Concurrent_Type
(T
))
1682 and then not Is_Constrained
(T
)
1683 and then Has_Discriminants
(T
)
1685 Act_T
:= Build_Default_Subtype
;
1686 Rewrite
(Object_Definition
(N
), New_Occurrence_Of
(Act_T
, Loc
));
1688 elsif not Is_Constrained
(T
)
1689 and then Has_Discriminants
(T
)
1690 and then Constant_Present
(N
)
1691 and then Nkind
(E
) = N_Function_Call
1693 -- The back-end has problems with constants of a discriminated type
1694 -- with defaults, if the initial value is a function call. We
1695 -- generate an intermediate temporary for the result of the call.
1696 -- It is unclear why this should make it acceptable to gcc. ???
1698 Remove_Side_Effects
(E
);
1701 if T
= Standard_Wide_Character
1702 or else Root_Type
(T
) = Standard_Wide_String
1704 Check_Restriction
(No_Wide_Characters
, Object_Definition
(N
));
1707 -- Now establish the proper kind and type of the object
1709 if Constant_Present
(N
) then
1710 Set_Ekind
(Id
, E_Constant
);
1711 Set_Never_Set_In_Source
(Id
, True);
1712 Set_Is_True_Constant
(Id
, True);
1715 Set_Ekind
(Id
, E_Variable
);
1717 -- A variable is set as shared passive if it appears in a shared
1718 -- passive package, and is at the outer level. This is not done
1719 -- for entities generated during expansion, because those are
1720 -- always manipulated locally.
1722 if Is_Shared_Passive
(Current_Scope
)
1723 and then Is_Library_Level_Entity
(Id
)
1724 and then Comes_From_Source
(Id
)
1726 Set_Is_Shared_Passive
(Id
);
1727 Check_Shared_Var
(Id
, T
, N
);
1730 -- Case of no initializing expression present. If the type is not
1731 -- fully initialized, then we set Never_Set_In_Source, since this
1732 -- is a case of a potentially uninitialized object. Note that we
1733 -- do not consider access variables to be fully initialized for
1734 -- this purpose, since it still seems dubious if someone declares
1736 -- Note that we only do this for source declarations. If the object
1737 -- is declared by a generated declaration, we assume that it is not
1738 -- appropriate to generate warnings in that case.
1741 if (Is_Access_Type
(T
)
1742 or else not Is_Fully_Initialized_Type
(T
))
1743 and then Comes_From_Source
(N
)
1745 Set_Never_Set_In_Source
(Id
);
1750 Init_Alignment
(Id
);
1753 if Aliased_Present
(N
) then
1754 Set_Is_Aliased
(Id
);
1757 and then Is_Record_Type
(T
)
1758 and then not Is_Constrained
(T
)
1759 and then Has_Discriminants
(T
)
1761 Set_Actual_Subtype
(Id
, Build_Default_Subtype
);
1765 Set_Etype
(Id
, Act_T
);
1767 if Has_Controlled_Component
(Etype
(Id
))
1768 or else Is_Controlled
(Etype
(Id
))
1770 if not Is_Library_Level_Entity
(Id
) then
1771 Check_Restriction
(No_Nested_Finalization
, N
);
1774 Validate_Controlled_Object
(Id
);
1777 -- Generate a warning when an initialization causes an obvious
1778 -- ABE violation. If the init expression is a simple aggregate
1779 -- there shouldn't be any initialize/adjust call generated. This
1780 -- will be true as soon as aggregates are built in place when
1781 -- possible. ??? at the moment we do not generate warnings for
1782 -- temporaries created for those aggregates although a
1783 -- Program_Error might be generated if compiled with -gnato
1785 if Is_Controlled
(Etype
(Id
))
1786 and then Comes_From_Source
(Id
)
1789 BT
: constant Entity_Id
:= Base_Type
(Etype
(Id
));
1791 Implicit_Call
: Entity_Id
;
1792 pragma Warnings
(Off
, Implicit_Call
);
1793 -- What is this about, it is never referenced ???
1795 function Is_Aggr
(N
: Node_Id
) return Boolean;
1796 -- Check that N is an aggregate
1802 function Is_Aggr
(N
: Node_Id
) return Boolean is
1804 case Nkind
(Original_Node
(N
)) is
1805 when N_Aggregate | N_Extension_Aggregate
=>
1808 when N_Qualified_Expression |
1810 N_Unchecked_Type_Conversion
=>
1811 return Is_Aggr
(Expression
(Original_Node
(N
)));
1819 -- If no underlying type, we already are in an error situation
1820 -- don't try to add a warning since we do not have access
1823 if No
(Underlying_Type
(BT
)) then
1824 Implicit_Call
:= Empty
;
1826 -- A generic type does not have usable primitive operators.
1827 -- Initialization calls are built for instances.
1829 elsif Is_Generic_Type
(BT
) then
1830 Implicit_Call
:= Empty
;
1832 -- if the init expression is not an aggregate, an adjust
1833 -- call will be generated
1835 elsif Present
(E
) and then not Is_Aggr
(E
) then
1836 Implicit_Call
:= Find_Prim_Op
(BT
, Name_Adjust
);
1838 -- if no init expression and we are not in the deferred
1839 -- constant case, an Initialize call will be generated
1841 elsif No
(E
) and then not Constant_Present
(N
) then
1842 Implicit_Call
:= Find_Prim_Op
(BT
, Name_Initialize
);
1845 Implicit_Call
:= Empty
;
1851 if Has_Task
(Etype
(Id
)) then
1852 Check_Restriction
(Max_Tasks
, N
);
1854 if not Is_Library_Level_Entity
(Id
) then
1855 Check_Restriction
(No_Task_Hierarchy
, N
);
1856 Check_Potentially_Blocking_Operation
(N
);
1859 -- A rather specialized test. If we see two tasks being declared
1860 -- of the same type in the same object declaration, and the task
1861 -- has an entry with an address clause, we know that program error
1862 -- will be raised at run-time since we can't have two tasks with
1863 -- entries at the same address.
1865 if Is_Task_Type
(Etype
(Id
))
1866 and then More_Ids
(N
)
1872 E
:= First_Entity
(Etype
(Id
));
1873 while Present
(E
) loop
1874 if Ekind
(E
) = E_Entry
1875 and then Present
(Get_Attribute_Definition_Clause
1876 (E
, Attribute_Address
))
1879 ("?more than one task with same entry address", N
);
1881 ("\?Program_Error will be raised at run time", N
);
1883 Make_Raise_Program_Error
(Loc
,
1884 Reason
=> PE_Duplicated_Entry_Address
));
1894 -- Some simple constant-propagation: if the expression is a constant
1895 -- string initialized with a literal, share the literal. This avoids
1899 and then Is_Entity_Name
(E
)
1900 and then Ekind
(Entity
(E
)) = E_Constant
1901 and then Base_Type
(Etype
(E
)) = Standard_String
1904 Val
: constant Node_Id
:= Constant_Value
(Entity
(E
));
1908 and then Nkind
(Val
) = N_String_Literal
1910 Rewrite
(E
, New_Copy
(Val
));
1915 -- Another optimization: if the nominal subtype is unconstrained and
1916 -- the expression is a function call that returns an unconstrained
1917 -- type, rewrite the declaration as a renaming of the result of the
1918 -- call. The exceptions below are cases where the copy is expected,
1919 -- either by the back end (Aliased case) or by the semantics, as for
1920 -- initializing controlled types or copying tags for classwide types.
1923 and then Nkind
(E
) = N_Explicit_Dereference
1924 and then Nkind
(Original_Node
(E
)) = N_Function_Call
1925 and then not Is_Library_Level_Entity
(Id
)
1926 and then not Is_Constrained
(T
)
1927 and then not Is_Aliased
(Id
)
1928 and then not Is_Class_Wide_Type
(T
)
1929 and then not Is_Controlled
(T
)
1930 and then not Has_Controlled_Component
(Base_Type
(T
))
1931 and then Expander_Active
1934 Make_Object_Renaming_Declaration
(Loc
,
1935 Defining_Identifier
=> Id
,
1936 Subtype_Mark
=> New_Occurrence_Of
1937 (Base_Type
(Etype
(Id
)), Loc
),
1940 Set_Renamed_Object
(Id
, E
);
1942 -- Force generation of debugging information for the constant
1943 -- and for the renamed function call.
1945 Set_Needs_Debug_Info
(Id
);
1946 Set_Needs_Debug_Info
(Entity
(Prefix
(E
)));
1949 if Present
(Prev_Entity
)
1950 and then Is_Frozen
(Prev_Entity
)
1951 and then not Error_Posted
(Id
)
1953 Error_Msg_N
("full constant declaration appears too late", N
);
1956 Check_Eliminated
(Id
);
1957 end Analyze_Object_Declaration
;
1959 ---------------------------
1960 -- Analyze_Others_Choice --
1961 ---------------------------
1963 -- Nothing to do for the others choice node itself, the semantic analysis
1964 -- of the others choice will occur as part of the processing of the parent
1966 procedure Analyze_Others_Choice
(N
: Node_Id
) is
1967 pragma Warnings
(Off
, N
);
1971 end Analyze_Others_Choice
;
1973 --------------------------------
1974 -- Analyze_Per_Use_Expression --
1975 --------------------------------
1977 procedure Analyze_Per_Use_Expression
(N
: Node_Id
; T
: Entity_Id
) is
1978 Save_In_Default_Expression
: constant Boolean := In_Default_Expression
;
1981 In_Default_Expression
:= True;
1982 Pre_Analyze_And_Resolve
(N
, T
);
1983 In_Default_Expression
:= Save_In_Default_Expression
;
1984 end Analyze_Per_Use_Expression
;
1986 -------------------------------------------
1987 -- Analyze_Private_Extension_Declaration --
1988 -------------------------------------------
1990 procedure Analyze_Private_Extension_Declaration
(N
: Node_Id
) is
1991 T
: constant Entity_Id
:= Defining_Identifier
(N
);
1992 Indic
: constant Node_Id
:= Subtype_Indication
(N
);
1993 Parent_Type
: Entity_Id
;
1994 Parent_Base
: Entity_Id
;
1997 Generate_Definition
(T
);
2000 Parent_Type
:= Find_Type_Of_Subtype_Indic
(Indic
);
2001 Parent_Base
:= Base_Type
(Parent_Type
);
2003 if Parent_Type
= Any_Type
2004 or else Etype
(Parent_Type
) = Any_Type
2006 Set_Ekind
(T
, Ekind
(Parent_Type
));
2007 Set_Etype
(T
, Any_Type
);
2010 elsif not Is_Tagged_Type
(Parent_Type
) then
2012 ("parent of type extension must be a tagged type ", Indic
);
2015 elsif Ekind
(Parent_Type
) = E_Void
2016 or else Ekind
(Parent_Type
) = E_Incomplete_Type
2018 Error_Msg_N
("premature derivation of incomplete type", Indic
);
2022 -- Perhaps the parent type should be changed to the class-wide type's
2023 -- specific type in this case to prevent cascading errors ???
2025 if Is_Class_Wide_Type
(Parent_Type
) then
2027 ("parent of type extension must not be a class-wide type", Indic
);
2031 if (not Is_Package
(Current_Scope
)
2032 and then Nkind
(Parent
(N
)) /= N_Generic_Subprogram_Declaration
)
2033 or else In_Private_Part
(Current_Scope
)
2036 Error_Msg_N
("invalid context for private extension", N
);
2039 -- Set common attributes
2041 Set_Is_Pure
(T
, Is_Pure
(Current_Scope
));
2042 Set_Scope
(T
, Current_Scope
);
2043 Set_Ekind
(T
, E_Record_Type_With_Private
);
2044 Init_Size_Align
(T
);
2046 Set_Etype
(T
, Parent_Base
);
2047 Set_Has_Task
(T
, Has_Task
(Parent_Base
));
2049 Set_Convention
(T
, Convention
(Parent_Type
));
2050 Set_First_Rep_Item
(T
, First_Rep_Item
(Parent_Type
));
2051 Set_Is_First_Subtype
(T
);
2052 Make_Class_Wide_Type
(T
);
2054 Build_Derived_Record_Type
(N
, Parent_Type
, T
);
2055 end Analyze_Private_Extension_Declaration
;
2057 ---------------------------------
2058 -- Analyze_Subtype_Declaration --
2059 ---------------------------------
2061 procedure Analyze_Subtype_Declaration
(N
: Node_Id
) is
2062 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
2064 R_Checks
: Check_Result
;
2067 Generate_Definition
(Id
);
2068 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
2069 Init_Size_Align
(Id
);
2071 -- The following guard condition on Enter_Name is to handle cases
2072 -- where the defining identifier has already been entered into the
2073 -- scope but the declaration as a whole needs to be analyzed.
2075 -- This case in particular happens for derived enumeration types.
2076 -- The derived enumeration type is processed as an inserted enumeration
2077 -- type declaration followed by a rewritten subtype declaration. The
2078 -- defining identifier, however, is entered into the name scope very
2079 -- early in the processing of the original type declaration and
2080 -- therefore needs to be avoided here, when the created subtype
2081 -- declaration is analyzed. (See Build_Derived_Types)
2083 -- This also happens when the full view of a private type is a
2084 -- derived type with constraints. In this case the entity has been
2085 -- introduced in the private declaration.
2087 if Present
(Etype
(Id
))
2088 and then (Is_Private_Type
(Etype
(Id
))
2089 or else Is_Task_Type
(Etype
(Id
))
2090 or else Is_Rewrite_Substitution
(N
))
2098 T
:= Process_Subtype
(Subtype_Indication
(N
), N
, Id
, 'P');
2100 -- Inherit common attributes
2102 Set_Is_Generic_Type
(Id
, Is_Generic_Type
(Base_Type
(T
)));
2103 Set_Is_Volatile
(Id
, Is_Volatile
(T
));
2104 Set_Treat_As_Volatile
(Id
, Treat_As_Volatile
(T
));
2105 Set_Is_Atomic
(Id
, Is_Atomic
(T
));
2107 -- In the case where there is no constraint given in the subtype
2108 -- indication, Process_Subtype just returns the Subtype_Mark,
2109 -- so its semantic attributes must be established here.
2111 if Nkind
(Subtype_Indication
(N
)) /= N_Subtype_Indication
then
2112 Set_Etype
(Id
, Base_Type
(T
));
2116 Set_Ekind
(Id
, E_Array_Subtype
);
2118 -- Shouldn't we call Copy_Array_Subtype_Attributes here???
2120 Set_First_Index
(Id
, First_Index
(T
));
2121 Set_Is_Aliased
(Id
, Is_Aliased
(T
));
2122 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2124 when Decimal_Fixed_Point_Kind
=>
2125 Set_Ekind
(Id
, E_Decimal_Fixed_Point_Subtype
);
2126 Set_Digits_Value
(Id
, Digits_Value
(T
));
2127 Set_Delta_Value
(Id
, Delta_Value
(T
));
2128 Set_Scale_Value
(Id
, Scale_Value
(T
));
2129 Set_Small_Value
(Id
, Small_Value
(T
));
2130 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2131 Set_Machine_Radix_10
(Id
, Machine_Radix_10
(T
));
2132 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2133 Set_RM_Size
(Id
, RM_Size
(T
));
2135 when Enumeration_Kind
=>
2136 Set_Ekind
(Id
, E_Enumeration_Subtype
);
2137 Set_First_Literal
(Id
, First_Literal
(Base_Type
(T
)));
2138 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2139 Set_Is_Character_Type
(Id
, Is_Character_Type
(T
));
2140 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2141 Set_RM_Size
(Id
, RM_Size
(T
));
2143 when Ordinary_Fixed_Point_Kind
=>
2144 Set_Ekind
(Id
, E_Ordinary_Fixed_Point_Subtype
);
2145 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2146 Set_Small_Value
(Id
, Small_Value
(T
));
2147 Set_Delta_Value
(Id
, Delta_Value
(T
));
2148 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2149 Set_RM_Size
(Id
, RM_Size
(T
));
2152 Set_Ekind
(Id
, E_Floating_Point_Subtype
);
2153 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2154 Set_Digits_Value
(Id
, Digits_Value
(T
));
2155 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2157 when Signed_Integer_Kind
=>
2158 Set_Ekind
(Id
, E_Signed_Integer_Subtype
);
2159 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2160 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2161 Set_RM_Size
(Id
, RM_Size
(T
));
2163 when Modular_Integer_Kind
=>
2164 Set_Ekind
(Id
, E_Modular_Integer_Subtype
);
2165 Set_Scalar_Range
(Id
, Scalar_Range
(T
));
2166 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2167 Set_RM_Size
(Id
, RM_Size
(T
));
2169 when Class_Wide_Kind
=>
2170 Set_Ekind
(Id
, E_Class_Wide_Subtype
);
2171 Set_First_Entity
(Id
, First_Entity
(T
));
2172 Set_Last_Entity
(Id
, Last_Entity
(T
));
2173 Set_Class_Wide_Type
(Id
, Class_Wide_Type
(T
));
2174 Set_Cloned_Subtype
(Id
, T
);
2175 Set_Is_Tagged_Type
(Id
, True);
2176 Set_Has_Unknown_Discriminants
2179 if Ekind
(T
) = E_Class_Wide_Subtype
then
2180 Set_Equivalent_Type
(Id
, Equivalent_Type
(T
));
2183 when E_Record_Type | E_Record_Subtype
=>
2184 Set_Ekind
(Id
, E_Record_Subtype
);
2186 if Ekind
(T
) = E_Record_Subtype
2187 and then Present
(Cloned_Subtype
(T
))
2189 Set_Cloned_Subtype
(Id
, Cloned_Subtype
(T
));
2191 Set_Cloned_Subtype
(Id
, T
);
2194 Set_First_Entity
(Id
, First_Entity
(T
));
2195 Set_Last_Entity
(Id
, Last_Entity
(T
));
2196 Set_Has_Discriminants
(Id
, Has_Discriminants
(T
));
2197 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2198 Set_Is_Limited_Record
(Id
, Is_Limited_Record
(T
));
2199 Set_Has_Unknown_Discriminants
2200 (Id
, Has_Unknown_Discriminants
(T
));
2202 if Has_Discriminants
(T
) then
2203 Set_Discriminant_Constraint
2204 (Id
, Discriminant_Constraint
(T
));
2205 Set_Stored_Constraint_From_Discriminant_Constraint
(Id
);
2207 elsif Has_Unknown_Discriminants
(Id
) then
2208 Set_Discriminant_Constraint
(Id
, No_Elist
);
2211 if Is_Tagged_Type
(T
) then
2212 Set_Is_Tagged_Type
(Id
);
2213 Set_Is_Abstract
(Id
, Is_Abstract
(T
));
2214 Set_Primitive_Operations
2215 (Id
, Primitive_Operations
(T
));
2216 Set_Class_Wide_Type
(Id
, Class_Wide_Type
(T
));
2219 when Private_Kind
=>
2220 Set_Ekind
(Id
, Subtype_Kind
(Ekind
(T
)));
2221 Set_Has_Discriminants
(Id
, Has_Discriminants
(T
));
2222 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2223 Set_First_Entity
(Id
, First_Entity
(T
));
2224 Set_Last_Entity
(Id
, Last_Entity
(T
));
2225 Set_Private_Dependents
(Id
, New_Elmt_List
);
2226 Set_Is_Limited_Record
(Id
, Is_Limited_Record
(T
));
2227 Set_Has_Unknown_Discriminants
2228 (Id
, Has_Unknown_Discriminants
(T
));
2230 if Is_Tagged_Type
(T
) then
2231 Set_Is_Tagged_Type
(Id
);
2232 Set_Is_Abstract
(Id
, Is_Abstract
(T
));
2233 Set_Primitive_Operations
2234 (Id
, Primitive_Operations
(T
));
2235 Set_Class_Wide_Type
(Id
, Class_Wide_Type
(T
));
2238 -- In general the attributes of the subtype of a private
2239 -- type are the attributes of the partial view of parent.
2240 -- However, the full view may be a discriminated type,
2241 -- and the subtype must share the discriminant constraint
2242 -- to generate correct calls to initialization procedures.
2244 if Has_Discriminants
(T
) then
2245 Set_Discriminant_Constraint
2246 (Id
, Discriminant_Constraint
(T
));
2247 Set_Stored_Constraint_From_Discriminant_Constraint
(Id
);
2249 elsif Present
(Full_View
(T
))
2250 and then Has_Discriminants
(Full_View
(T
))
2252 Set_Discriminant_Constraint
2253 (Id
, Discriminant_Constraint
(Full_View
(T
)));
2254 Set_Stored_Constraint_From_Discriminant_Constraint
(Id
);
2256 -- This would seem semantically correct, but apparently
2257 -- confuses the back-end (4412-009). To be explained ???
2259 -- Set_Has_Discriminants (Id);
2262 Prepare_Private_Subtype_Completion
(Id
, N
);
2265 Set_Ekind
(Id
, E_Access_Subtype
);
2266 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2267 Set_Is_Access_Constant
2268 (Id
, Is_Access_Constant
(T
));
2269 Set_Directly_Designated_Type
2270 (Id
, Designated_Type
(T
));
2272 -- A Pure library_item must not contain the declaration of a
2273 -- named access type, except within a subprogram, generic
2274 -- subprogram, task unit, or protected unit (RM 10.2.1(16)).
2276 if Comes_From_Source
(Id
)
2277 and then In_Pure_Unit
2278 and then not In_Subprogram_Task_Protected_Unit
2281 ("named access types not allowed in pure unit", N
);
2284 when Concurrent_Kind
=>
2285 Set_Ekind
(Id
, Subtype_Kind
(Ekind
(T
)));
2286 Set_Corresponding_Record_Type
(Id
,
2287 Corresponding_Record_Type
(T
));
2288 Set_First_Entity
(Id
, First_Entity
(T
));
2289 Set_First_Private_Entity
(Id
, First_Private_Entity
(T
));
2290 Set_Has_Discriminants
(Id
, Has_Discriminants
(T
));
2291 Set_Is_Constrained
(Id
, Is_Constrained
(T
));
2292 Set_Last_Entity
(Id
, Last_Entity
(T
));
2294 if Has_Discriminants
(T
) then
2295 Set_Discriminant_Constraint
(Id
,
2296 Discriminant_Constraint
(T
));
2297 Set_Stored_Constraint_From_Discriminant_Constraint
(Id
);
2300 -- If the subtype name denotes an incomplete type
2301 -- an error was already reported by Process_Subtype.
2303 when E_Incomplete_Type
=>
2304 Set_Etype
(Id
, Any_Type
);
2307 raise Program_Error
;
2311 if Etype
(Id
) = Any_Type
then
2315 -- Some common processing on all types
2317 Set_Size_Info
(Id
, T
);
2318 Set_First_Rep_Item
(Id
, First_Rep_Item
(T
));
2322 Set_Is_Immediately_Visible
(Id
, True);
2323 Set_Depends_On_Private
(Id
, Has_Private_Component
(T
));
2325 if Present
(Generic_Parent_Type
(N
))
2328 (Parent
(Generic_Parent_Type
(N
))) /= N_Formal_Type_Declaration
2330 (Formal_Type_Definition
(Parent
(Generic_Parent_Type
(N
))))
2331 /= N_Formal_Private_Type_Definition
)
2333 if Is_Tagged_Type
(Id
) then
2334 if Is_Class_Wide_Type
(Id
) then
2335 Derive_Subprograms
(Generic_Parent_Type
(N
), Id
, Etype
(T
));
2337 Derive_Subprograms
(Generic_Parent_Type
(N
), Id
, T
);
2340 elsif Scope
(Etype
(Id
)) /= Standard_Standard
then
2341 Derive_Subprograms
(Generic_Parent_Type
(N
), Id
);
2345 if Is_Private_Type
(T
)
2346 and then Present
(Full_View
(T
))
2348 Conditional_Delay
(Id
, Full_View
(T
));
2350 -- The subtypes of components or subcomponents of protected types
2351 -- do not need freeze nodes, which would otherwise appear in the
2352 -- wrong scope (before the freeze node for the protected type). The
2353 -- proper subtypes are those of the subcomponents of the corresponding
2356 elsif Ekind
(Scope
(Id
)) /= E_Protected_Type
2357 and then Present
(Scope
(Scope
(Id
))) -- error defense!
2358 and then Ekind
(Scope
(Scope
(Id
))) /= E_Protected_Type
2360 Conditional_Delay
(Id
, T
);
2363 -- Check that constraint_error is raised for a scalar subtype
2364 -- indication when the lower or upper bound of a non-null range
2365 -- lies outside the range of the type mark.
2367 if Nkind
(Subtype_Indication
(N
)) = N_Subtype_Indication
then
2368 if Is_Scalar_Type
(Etype
(Id
))
2369 and then Scalar_Range
(Id
) /=
2370 Scalar_Range
(Etype
(Subtype_Mark
2371 (Subtype_Indication
(N
))))
2375 Etype
(Subtype_Mark
(Subtype_Indication
(N
))));
2377 elsif Is_Array_Type
(Etype
(Id
))
2378 and then Present
(First_Index
(Id
))
2380 -- This really should be a subprogram that finds the indications
2383 if ((Nkind
(First_Index
(Id
)) = N_Identifier
2384 and then Ekind
(Entity
(First_Index
(Id
))) in Scalar_Kind
)
2385 or else Nkind
(First_Index
(Id
)) = N_Subtype_Indication
)
2387 Nkind
(Scalar_Range
(Etype
(First_Index
(Id
)))) = N_Range
2390 Target_Typ
: constant Entity_Id
:=
2393 (Subtype_Mark
(Subtype_Indication
(N
)))));
2397 (Scalar_Range
(Etype
(First_Index
(Id
))),
2399 Etype
(First_Index
(Id
)),
2400 Defining_Identifier
(N
));
2406 Sloc
(Defining_Identifier
(N
)));
2412 Check_Eliminated
(Id
);
2413 end Analyze_Subtype_Declaration
;
2415 --------------------------------
2416 -- Analyze_Subtype_Indication --
2417 --------------------------------
2419 procedure Analyze_Subtype_Indication
(N
: Node_Id
) is
2420 T
: constant Entity_Id
:= Subtype_Mark
(N
);
2421 R
: constant Node_Id
:= Range_Expression
(Constraint
(N
));
2428 Set_Etype
(N
, Etype
(R
));
2430 Set_Error_Posted
(R
);
2431 Set_Error_Posted
(T
);
2433 end Analyze_Subtype_Indication
;
2435 ------------------------------
2436 -- Analyze_Type_Declaration --
2437 ------------------------------
2439 procedure Analyze_Type_Declaration
(N
: Node_Id
) is
2440 Def
: constant Node_Id
:= Type_Definition
(N
);
2441 Def_Id
: constant Entity_Id
:= Defining_Identifier
(N
);
2445 Is_Remote
: constant Boolean :=
2446 (Is_Remote_Types
(Current_Scope
)
2447 or else Is_Remote_Call_Interface
(Current_Scope
))
2448 and then not (In_Private_Part
(Current_Scope
)
2450 In_Package_Body
(Current_Scope
));
2453 Prev
:= Find_Type_Name
(N
);
2455 -- The full view, if present, now points to the current type
2457 -- Ada0Y (AI-50217): If the type was previously decorated when imported
2458 -- through a LIMITED WITH clause, it appears as incomplete but has no
2461 if Ekind
(Prev
) = E_Incomplete_Type
2462 and then Present
(Full_View
(Prev
))
2464 T
:= Full_View
(Prev
);
2469 Set_Is_Pure
(T
, Is_Pure
(Current_Scope
));
2471 -- We set the flag Is_First_Subtype here. It is needed to set the
2472 -- corresponding flag for the Implicit class-wide-type created
2473 -- during tagged types processing.
2475 Set_Is_First_Subtype
(T
, True);
2477 -- Only composite types other than array types are allowed to have
2482 -- For derived types, the rule will be checked once we've figured
2483 -- out the parent type.
2485 when N_Derived_Type_Definition
=>
2488 -- For record types, discriminants are allowed.
2490 when N_Record_Definition
=>
2494 if Present
(Discriminant_Specifications
(N
)) then
2496 ("elementary or array type cannot have discriminants",
2498 (First
(Discriminant_Specifications
(N
))));
2502 -- Elaborate the type definition according to kind, and generate
2503 -- subsidiary (implicit) subtypes where needed. We skip this if
2504 -- it was already done (this happens during the reanalysis that
2505 -- follows a call to the high level optimizer).
2507 if not Analyzed
(T
) then
2512 when N_Access_To_Subprogram_Definition
=>
2513 Access_Subprogram_Declaration
(T
, Def
);
2515 -- If this is a remote access to subprogram, we must create
2516 -- the equivalent fat pointer type, and related subprograms.
2519 Process_Remote_AST_Declaration
(N
);
2522 -- Validate categorization rule against access type declaration
2523 -- usually a violation in Pure unit, Shared_Passive unit.
2525 Validate_Access_Type_Declaration
(T
, N
);
2527 when N_Access_To_Object_Definition
=>
2528 Access_Type_Declaration
(T
, Def
);
2530 -- Validate categorization rule against access type declaration
2531 -- usually a violation in Pure unit, Shared_Passive unit.
2533 Validate_Access_Type_Declaration
(T
, N
);
2535 -- If we are in a Remote_Call_Interface package and define
2536 -- a RACW, Read and Write attribute must be added.
2539 and then Is_Remote_Access_To_Class_Wide_Type
(Def_Id
)
2541 Add_RACW_Features
(Def_Id
);
2544 when N_Array_Type_Definition
=>
2545 Array_Type_Declaration
(T
, Def
);
2547 when N_Derived_Type_Definition
=>
2548 Derived_Type_Declaration
(T
, N
, T
/= Def_Id
);
2550 when N_Enumeration_Type_Definition
=>
2551 Enumeration_Type_Declaration
(T
, Def
);
2553 when N_Floating_Point_Definition
=>
2554 Floating_Point_Type_Declaration
(T
, Def
);
2556 when N_Decimal_Fixed_Point_Definition
=>
2557 Decimal_Fixed_Point_Type_Declaration
(T
, Def
);
2559 when N_Ordinary_Fixed_Point_Definition
=>
2560 Ordinary_Fixed_Point_Type_Declaration
(T
, Def
);
2562 when N_Signed_Integer_Type_Definition
=>
2563 Signed_Integer_Type_Declaration
(T
, Def
);
2565 when N_Modular_Type_Definition
=>
2566 Modular_Type_Declaration
(T
, Def
);
2568 when N_Record_Definition
=>
2569 Record_Type_Declaration
(T
, N
, Prev
);
2572 raise Program_Error
;
2577 if Etype
(T
) = Any_Type
then
2581 -- Some common processing for all types
2583 Set_Depends_On_Private
(T
, Has_Private_Component
(T
));
2585 -- Both the declared entity, and its anonymous base type if one
2586 -- was created, need freeze nodes allocated.
2589 B
: constant Entity_Id
:= Base_Type
(T
);
2592 -- In the case where the base type is different from the first
2593 -- subtype, we pre-allocate a freeze node, and set the proper
2594 -- link to the first subtype. Freeze_Entity will use this
2595 -- preallocated freeze node when it freezes the entity.
2598 Ensure_Freeze_Node
(B
);
2599 Set_First_Subtype_Link
(Freeze_Node
(B
), T
);
2602 if not From_With_Type
(T
) then
2603 Set_Has_Delayed_Freeze
(T
);
2607 -- Case of T is the full declaration of some private type which has
2608 -- been swapped in Defining_Identifier (N).
2610 if T
/= Def_Id
and then Is_Private_Type
(Def_Id
) then
2611 Process_Full_View
(N
, T
, Def_Id
);
2613 -- Record the reference. The form of this is a little strange,
2614 -- since the full declaration has been swapped in. So the first
2615 -- parameter here represents the entity to which a reference is
2616 -- made which is the "real" entity, i.e. the one swapped in,
2617 -- and the second parameter provides the reference location.
2619 Generate_Reference
(T
, T
, 'c');
2620 Set_Completion_Referenced
(Def_Id
);
2622 -- For completion of incomplete type, process incomplete dependents
2623 -- and always mark the full type as referenced (it is the incomplete
2624 -- type that we get for any real reference).
2626 elsif Ekind
(Prev
) = E_Incomplete_Type
then
2627 Process_Incomplete_Dependents
(N
, T
, Prev
);
2628 Generate_Reference
(Prev
, Def_Id
, 'c');
2629 Set_Completion_Referenced
(Def_Id
);
2631 -- If not private type or incomplete type completion, this is a real
2632 -- definition of a new entity, so record it.
2635 Generate_Definition
(Def_Id
);
2638 Check_Eliminated
(Def_Id
);
2639 end Analyze_Type_Declaration
;
2641 --------------------------
2642 -- Analyze_Variant_Part --
2643 --------------------------
2645 procedure Analyze_Variant_Part
(N
: Node_Id
) is
2647 procedure Non_Static_Choice_Error
(Choice
: Node_Id
);
2648 -- Error routine invoked by the generic instantiation below when
2649 -- the variant part has a non static choice.
2651 procedure Process_Declarations
(Variant
: Node_Id
);
2652 -- Analyzes all the declarations associated with a Variant.
2653 -- Needed by the generic instantiation below.
2655 package Variant_Choices_Processing
is new
2656 Generic_Choices_Processing
2657 (Get_Alternatives
=> Variants
,
2658 Get_Choices
=> Discrete_Choices
,
2659 Process_Empty_Choice
=> No_OP
,
2660 Process_Non_Static_Choice
=> Non_Static_Choice_Error
,
2661 Process_Associated_Node
=> Process_Declarations
);
2662 use Variant_Choices_Processing
;
2663 -- Instantiation of the generic choice processing package.
2665 -----------------------------
2666 -- Non_Static_Choice_Error --
2667 -----------------------------
2669 procedure Non_Static_Choice_Error
(Choice
: Node_Id
) is
2671 Flag_Non_Static_Expr
2672 ("choice given in variant part is not static!", Choice
);
2673 end Non_Static_Choice_Error
;
2675 --------------------------
2676 -- Process_Declarations --
2677 --------------------------
2679 procedure Process_Declarations
(Variant
: Node_Id
) is
2681 if not Null_Present
(Component_List
(Variant
)) then
2682 Analyze_Declarations
(Component_Items
(Component_List
(Variant
)));
2684 if Present
(Variant_Part
(Component_List
(Variant
))) then
2685 Analyze
(Variant_Part
(Component_List
(Variant
)));
2688 end Process_Declarations
;
2690 -- Variables local to Analyze_Case_Statement.
2692 Discr_Name
: Node_Id
;
2693 Discr_Type
: Entity_Id
;
2695 Case_Table
: Choice_Table_Type
(1 .. Number_Of_Choices
(N
));
2697 Dont_Care
: Boolean;
2698 Others_Present
: Boolean := False;
2700 -- Start of processing for Analyze_Variant_Part
2703 Discr_Name
:= Name
(N
);
2704 Analyze
(Discr_Name
);
2706 if Ekind
(Entity
(Discr_Name
)) /= E_Discriminant
then
2707 Error_Msg_N
("invalid discriminant name in variant part", Discr_Name
);
2710 Discr_Type
:= Etype
(Entity
(Discr_Name
));
2712 if not Is_Discrete_Type
(Discr_Type
) then
2714 ("discriminant in a variant part must be of a discrete type",
2719 -- Call the instantiated Analyze_Choices which does the rest of the work
2722 (N
, Discr_Type
, Case_Table
, Last_Choice
, Dont_Care
, Others_Present
);
2723 end Analyze_Variant_Part
;
2725 ----------------------------
2726 -- Array_Type_Declaration --
2727 ----------------------------
2729 procedure Array_Type_Declaration
(T
: in out Entity_Id
; Def
: Node_Id
) is
2730 Component_Def
: constant Node_Id
:= Subtype_Indication
(Def
);
2731 Element_Type
: Entity_Id
;
2732 Implicit_Base
: Entity_Id
;
2734 Related_Id
: Entity_Id
:= Empty
;
2736 P
: constant Node_Id
:= Parent
(Def
);
2740 if Nkind
(Def
) = N_Constrained_Array_Definition
then
2742 Index
:= First
(Discrete_Subtype_Definitions
(Def
));
2744 -- Find proper names for the implicit types which may be public.
2745 -- in case of anonymous arrays we use the name of the first object
2746 -- of that type as prefix.
2749 Related_Id
:= Defining_Identifier
(P
);
2755 Index
:= First
(Subtype_Marks
(Def
));
2760 while Present
(Index
) loop
2762 Make_Index
(Index
, P
, Related_Id
, Nb_Index
);
2764 Nb_Index
:= Nb_Index
+ 1;
2767 Element_Type
:= Process_Subtype
(Component_Def
, P
, Related_Id
, 'C');
2769 -- Constrained array case
2772 T
:= Create_Itype
(E_Void
, P
, Related_Id
, 'T');
2775 if Nkind
(Def
) = N_Constrained_Array_Definition
then
2777 -- Establish Implicit_Base as unconstrained base type
2779 Implicit_Base
:= Create_Itype
(E_Array_Type
, P
, Related_Id
, 'B');
2781 Init_Size_Align
(Implicit_Base
);
2782 Set_Etype
(Implicit_Base
, Implicit_Base
);
2783 Set_Scope
(Implicit_Base
, Current_Scope
);
2784 Set_Has_Delayed_Freeze
(Implicit_Base
);
2786 -- The constrained array type is a subtype of the unconstrained one
2788 Set_Ekind
(T
, E_Array_Subtype
);
2789 Init_Size_Align
(T
);
2790 Set_Etype
(T
, Implicit_Base
);
2791 Set_Scope
(T
, Current_Scope
);
2792 Set_Is_Constrained
(T
, True);
2793 Set_First_Index
(T
, First
(Discrete_Subtype_Definitions
(Def
)));
2794 Set_Has_Delayed_Freeze
(T
);
2796 -- Complete setup of implicit base type
2798 Set_First_Index
(Implicit_Base
, First_Index
(T
));
2799 Set_Component_Type
(Implicit_Base
, Element_Type
);
2800 Set_Has_Task
(Implicit_Base
, Has_Task
(Element_Type
));
2801 Set_Component_Size
(Implicit_Base
, Uint_0
);
2802 Set_Has_Controlled_Component
2803 (Implicit_Base
, Has_Controlled_Component
2806 Is_Controlled
(Element_Type
));
2807 Set_Finalize_Storage_Only
2808 (Implicit_Base
, Finalize_Storage_Only
2811 -- Unconstrained array case
2814 Set_Ekind
(T
, E_Array_Type
);
2815 Init_Size_Align
(T
);
2817 Set_Scope
(T
, Current_Scope
);
2818 Set_Component_Size
(T
, Uint_0
);
2819 Set_Is_Constrained
(T
, False);
2820 Set_First_Index
(T
, First
(Subtype_Marks
(Def
)));
2821 Set_Has_Delayed_Freeze
(T
, True);
2822 Set_Has_Task
(T
, Has_Task
(Element_Type
));
2823 Set_Has_Controlled_Component
(T
, Has_Controlled_Component
2826 Is_Controlled
(Element_Type
));
2827 Set_Finalize_Storage_Only
(T
, Finalize_Storage_Only
2831 Set_Component_Type
(Base_Type
(T
), Element_Type
);
2833 if Aliased_Present
(Def
) then
2834 Set_Has_Aliased_Components
(Etype
(T
));
2837 Priv
:= Private_Component
(Element_Type
);
2839 if Present
(Priv
) then
2841 -- Check for circular definitions
2843 if Priv
= Any_Type
then
2844 Set_Component_Type
(Etype
(T
), Any_Type
);
2846 -- There is a gap in the visibility of operations on the composite
2847 -- type only if the component type is defined in a different scope.
2849 elsif Scope
(Priv
) = Current_Scope
then
2852 elsif Is_Limited_Type
(Priv
) then
2853 Set_Is_Limited_Composite
(Etype
(T
));
2854 Set_Is_Limited_Composite
(T
);
2856 Set_Is_Private_Composite
(Etype
(T
));
2857 Set_Is_Private_Composite
(T
);
2861 -- Create a concatenation operator for the new type. Internal
2862 -- array types created for packed entities do not need such, they
2863 -- are compatible with the user-defined type.
2865 if Number_Dimensions
(T
) = 1
2866 and then not Is_Packed_Array_Type
(T
)
2868 New_Concatenation_Op
(T
);
2871 -- In the case of an unconstrained array the parser has already
2872 -- verified that all the indices are unconstrained but we still
2873 -- need to make sure that the element type is constrained.
2875 if Is_Indefinite_Subtype
(Element_Type
) then
2877 ("unconstrained element type in array declaration ",
2880 elsif Is_Abstract
(Element_Type
) then
2881 Error_Msg_N
("The type of a component cannot be abstract ",
2885 end Array_Type_Declaration
;
2887 -------------------------------
2888 -- Build_Derived_Access_Type --
2889 -------------------------------
2891 procedure Build_Derived_Access_Type
2893 Parent_Type
: Entity_Id
;
2894 Derived_Type
: Entity_Id
)
2896 S
: constant Node_Id
:= Subtype_Indication
(Type_Definition
(N
));
2898 Desig_Type
: Entity_Id
;
2900 Discr_Con_Elist
: Elist_Id
;
2901 Discr_Con_El
: Elmt_Id
;
2906 -- Set the designated type so it is available in case this is
2907 -- an access to a self-referential type, e.g. a standard list
2908 -- type with a next pointer. Will be reset after subtype is built.
2910 Set_Directly_Designated_Type
(Derived_Type
,
2911 Designated_Type
(Parent_Type
));
2913 Subt
:= Process_Subtype
(S
, N
);
2915 if Nkind
(S
) /= N_Subtype_Indication
2916 and then Subt
/= Base_Type
(Subt
)
2918 Set_Ekind
(Derived_Type
, E_Access_Subtype
);
2921 if Ekind
(Derived_Type
) = E_Access_Subtype
then
2923 Pbase
: constant Entity_Id
:= Base_Type
(Parent_Type
);
2924 Ibase
: constant Entity_Id
:=
2925 Create_Itype
(Ekind
(Pbase
), N
, Derived_Type
, 'B');
2926 Svg_Chars
: constant Name_Id
:= Chars
(Ibase
);
2927 Svg_Next_E
: constant Entity_Id
:= Next_Entity
(Ibase
);
2930 Copy_Node
(Pbase
, Ibase
);
2932 Set_Chars
(Ibase
, Svg_Chars
);
2933 Set_Next_Entity
(Ibase
, Svg_Next_E
);
2934 Set_Sloc
(Ibase
, Sloc
(Derived_Type
));
2935 Set_Scope
(Ibase
, Scope
(Derived_Type
));
2936 Set_Freeze_Node
(Ibase
, Empty
);
2937 Set_Is_Frozen
(Ibase
, False);
2938 Set_Comes_From_Source
(Ibase
, False);
2939 Set_Is_First_Subtype
(Ibase
, False);
2941 Set_Etype
(Ibase
, Pbase
);
2942 Set_Etype
(Derived_Type
, Ibase
);
2946 Set_Directly_Designated_Type
2947 (Derived_Type
, Designated_Type
(Subt
));
2949 Set_Is_Constrained
(Derived_Type
, Is_Constrained
(Subt
));
2950 Set_Is_Access_Constant
(Derived_Type
, Is_Access_Constant
(Parent_Type
));
2951 Set_Size_Info
(Derived_Type
, Parent_Type
);
2952 Set_RM_Size
(Derived_Type
, RM_Size
(Parent_Type
));
2953 Set_Depends_On_Private
(Derived_Type
,
2954 Has_Private_Component
(Derived_Type
));
2955 Conditional_Delay
(Derived_Type
, Subt
);
2957 -- Note: we do not copy the Storage_Size_Variable, since
2958 -- we always go to the root type for this information.
2960 -- Apply range checks to discriminants for derived record case
2961 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
2963 Desig_Type
:= Designated_Type
(Derived_Type
);
2964 if Is_Composite_Type
(Desig_Type
)
2965 and then (not Is_Array_Type
(Desig_Type
))
2966 and then Has_Discriminants
(Desig_Type
)
2967 and then Base_Type
(Desig_Type
) /= Desig_Type
2969 Discr_Con_Elist
:= Discriminant_Constraint
(Desig_Type
);
2970 Discr_Con_El
:= First_Elmt
(Discr_Con_Elist
);
2972 Discr
:= First_Discriminant
(Base_Type
(Desig_Type
));
2973 while Present
(Discr_Con_El
) loop
2974 Apply_Range_Check
(Node
(Discr_Con_El
), Etype
(Discr
));
2975 Next_Elmt
(Discr_Con_El
);
2976 Next_Discriminant
(Discr
);
2979 end Build_Derived_Access_Type
;
2981 ------------------------------
2982 -- Build_Derived_Array_Type --
2983 ------------------------------
2985 procedure Build_Derived_Array_Type
2987 Parent_Type
: Entity_Id
;
2988 Derived_Type
: Entity_Id
)
2990 Loc
: constant Source_Ptr
:= Sloc
(N
);
2991 Tdef
: constant Node_Id
:= Type_Definition
(N
);
2992 Indic
: constant Node_Id
:= Subtype_Indication
(Tdef
);
2993 Parent_Base
: constant Entity_Id
:= Base_Type
(Parent_Type
);
2994 Implicit_Base
: Entity_Id
;
2995 New_Indic
: Node_Id
;
2997 procedure Make_Implicit_Base
;
2998 -- If the parent subtype is constrained, the derived type is a
2999 -- subtype of an implicit base type derived from the parent base.
3001 ------------------------
3002 -- Make_Implicit_Base --
3003 ------------------------
3005 procedure Make_Implicit_Base
is
3008 Create_Itype
(Ekind
(Parent_Base
), N
, Derived_Type
, 'B');
3010 Set_Ekind
(Implicit_Base
, Ekind
(Parent_Base
));
3011 Set_Etype
(Implicit_Base
, Parent_Base
);
3013 Copy_Array_Subtype_Attributes
(Implicit_Base
, Parent_Base
);
3014 Copy_Array_Base_Type_Attributes
(Implicit_Base
, Parent_Base
);
3016 Set_Has_Delayed_Freeze
(Implicit_Base
, True);
3017 end Make_Implicit_Base
;
3019 -- Start of processing for Build_Derived_Array_Type
3022 if not Is_Constrained
(Parent_Type
) then
3023 if Nkind
(Indic
) /= N_Subtype_Indication
then
3024 Set_Ekind
(Derived_Type
, E_Array_Type
);
3026 Copy_Array_Subtype_Attributes
(Derived_Type
, Parent_Type
);
3027 Copy_Array_Base_Type_Attributes
(Derived_Type
, Parent_Type
);
3029 Set_Has_Delayed_Freeze
(Derived_Type
, True);
3033 Set_Etype
(Derived_Type
, Implicit_Base
);
3036 Make_Subtype_Declaration
(Loc
,
3037 Defining_Identifier
=> Derived_Type
,
3038 Subtype_Indication
=>
3039 Make_Subtype_Indication
(Loc
,
3040 Subtype_Mark
=> New_Reference_To
(Implicit_Base
, Loc
),
3041 Constraint
=> Constraint
(Indic
)));
3043 Rewrite
(N
, New_Indic
);
3048 if Nkind
(Indic
) /= N_Subtype_Indication
then
3051 Set_Ekind
(Derived_Type
, Ekind
(Parent_Type
));
3052 Set_Etype
(Derived_Type
, Implicit_Base
);
3053 Copy_Array_Subtype_Attributes
(Derived_Type
, Parent_Type
);
3056 Error_Msg_N
("illegal constraint on constrained type", Indic
);
3060 -- If the parent type is not a derived type itself, and is
3061 -- declared in a closed scope (e.g., a subprogram), then we
3062 -- need to explicitly introduce the new type's concatenation
3063 -- operator since Derive_Subprograms will not inherit the
3064 -- parent's operator. If the parent type is unconstrained, the
3065 -- operator is of the unconstrained base type.
3067 if Number_Dimensions
(Parent_Type
) = 1
3068 and then not Is_Limited_Type
(Parent_Type
)
3069 and then not Is_Derived_Type
(Parent_Type
)
3070 and then not Is_Package
(Scope
(Base_Type
(Parent_Type
)))
3072 if not Is_Constrained
(Parent_Type
)
3073 and then Is_Constrained
(Derived_Type
)
3075 New_Concatenation_Op
(Implicit_Base
);
3077 New_Concatenation_Op
(Derived_Type
);
3080 end Build_Derived_Array_Type
;
3082 -----------------------------------
3083 -- Build_Derived_Concurrent_Type --
3084 -----------------------------------
3086 procedure Build_Derived_Concurrent_Type
3088 Parent_Type
: Entity_Id
;
3089 Derived_Type
: Entity_Id
)
3091 D_Constraint
: Node_Id
;
3092 Disc_Spec
: Node_Id
;
3093 Old_Disc
: Entity_Id
;
3094 New_Disc
: Entity_Id
;
3096 Constraint_Present
: constant Boolean :=
3097 Nkind
(Subtype_Indication
(Type_Definition
(N
)))
3098 = N_Subtype_Indication
;
3101 Set_Stored_Constraint
(Derived_Type
, No_Elist
);
3103 if Is_Task_Type
(Parent_Type
) then
3104 Set_Storage_Size_Variable
(Derived_Type
,
3105 Storage_Size_Variable
(Parent_Type
));
3108 if Present
(Discriminant_Specifications
(N
)) then
3109 New_Scope
(Derived_Type
);
3110 Check_Or_Process_Discriminants
(N
, Derived_Type
);
3113 elsif Constraint_Present
then
3115 -- Build constrained subtype and derive from it
3118 Loc
: constant Source_Ptr
:= Sloc
(N
);
3119 Anon
: constant Entity_Id
:=
3120 Make_Defining_Identifier
(Loc
,
3121 New_External_Name
(Chars
(Derived_Type
), 'T'));
3126 Make_Subtype_Declaration
(Loc
,
3127 Defining_Identifier
=> Anon
,
3128 Subtype_Indication
=>
3129 New_Copy_Tree
(Subtype_Indication
(Type_Definition
(N
))));
3130 Insert_Before
(N
, Decl
);
3131 Rewrite
(Subtype_Indication
(Type_Definition
(N
)),
3132 New_Occurrence_Of
(Anon
, Loc
));
3134 Set_Analyzed
(Derived_Type
, False);
3140 -- All attributes are inherited from parent. In particular,
3141 -- entries and the corresponding record type are the same.
3142 -- Discriminants may be renamed, and must be treated separately.
3144 Set_Has_Discriminants
3145 (Derived_Type
, Has_Discriminants
(Parent_Type
));
3146 Set_Corresponding_Record_Type
3147 (Derived_Type
, Corresponding_Record_Type
(Parent_Type
));
3149 if Constraint_Present
then
3151 if not Has_Discriminants
(Parent_Type
) then
3152 Error_Msg_N
("untagged parent must have discriminants", N
);
3154 elsif Present
(Discriminant_Specifications
(N
)) then
3156 -- Verify that new discriminants are used to constrain
3159 Old_Disc
:= First_Discriminant
(Parent_Type
);
3160 New_Disc
:= First_Discriminant
(Derived_Type
);
3161 Disc_Spec
:= First
(Discriminant_Specifications
(N
));
3165 (Constraint
(Subtype_Indication
(Type_Definition
(N
)))));
3167 while Present
(Old_Disc
) and then Present
(Disc_Spec
) loop
3169 if Nkind
(Discriminant_Type
(Disc_Spec
)) /=
3172 Analyze
(Discriminant_Type
(Disc_Spec
));
3174 if not Subtypes_Statically_Compatible
(
3175 Etype
(Discriminant_Type
(Disc_Spec
)),
3179 ("not statically compatible with parent discriminant",
3180 Discriminant_Type
(Disc_Spec
));
3184 if Nkind
(D_Constraint
) = N_Identifier
3185 and then Chars
(D_Constraint
) /=
3186 Chars
(Defining_Identifier
(Disc_Spec
))
3188 Error_Msg_N
("new discriminants must constrain old ones",
3191 Set_Corresponding_Discriminant
(New_Disc
, Old_Disc
);
3194 Next_Discriminant
(Old_Disc
);
3195 Next_Discriminant
(New_Disc
);
3199 if Present
(Old_Disc
) or else Present
(Disc_Spec
) then
3200 Error_Msg_N
("discriminant mismatch in derivation", N
);
3205 elsif Present
(Discriminant_Specifications
(N
)) then
3207 ("missing discriminant constraint in untagged derivation",
3211 if Present
(Discriminant_Specifications
(N
)) then
3213 Old_Disc
:= First_Discriminant
(Parent_Type
);
3215 while Present
(Old_Disc
) loop
3217 if No
(Next_Entity
(Old_Disc
))
3218 or else Ekind
(Next_Entity
(Old_Disc
)) /= E_Discriminant
3220 Set_Next_Entity
(Last_Entity
(Derived_Type
),
3221 Next_Entity
(Old_Disc
));
3225 Next_Discriminant
(Old_Disc
);
3229 Set_First_Entity
(Derived_Type
, First_Entity
(Parent_Type
));
3230 if Has_Discriminants
(Parent_Type
) then
3231 Set_Discriminant_Constraint
(
3232 Derived_Type
, Discriminant_Constraint
(Parent_Type
));
3236 Set_Last_Entity
(Derived_Type
, Last_Entity
(Parent_Type
));
3238 Set_Has_Completion
(Derived_Type
);
3239 end Build_Derived_Concurrent_Type
;
3241 ------------------------------------
3242 -- Build_Derived_Enumeration_Type --
3243 ------------------------------------
3245 procedure Build_Derived_Enumeration_Type
3247 Parent_Type
: Entity_Id
;
3248 Derived_Type
: Entity_Id
)
3250 Loc
: constant Source_Ptr
:= Sloc
(N
);
3251 Def
: constant Node_Id
:= Type_Definition
(N
);
3252 Indic
: constant Node_Id
:= Subtype_Indication
(Def
);
3253 Implicit_Base
: Entity_Id
;
3254 Literal
: Entity_Id
;
3255 New_Lit
: Entity_Id
;
3256 Literals_List
: List_Id
;
3257 Type_Decl
: Node_Id
;
3259 Rang_Expr
: Node_Id
;
3262 -- Since types Standard.Character and Standard.Wide_Character do
3263 -- not have explicit literals lists we need to process types derived
3264 -- from them specially. This is handled by Derived_Standard_Character.
3265 -- If the parent type is a generic type, there are no literals either,
3266 -- and we construct the same skeletal representation as for the generic
3269 if Root_Type
(Parent_Type
) = Standard_Character
3270 or else Root_Type
(Parent_Type
) = Standard_Wide_Character
3272 Derived_Standard_Character
(N
, Parent_Type
, Derived_Type
);
3274 elsif Is_Generic_Type
(Root_Type
(Parent_Type
)) then
3281 Make_Attribute_Reference
(Loc
,
3282 Attribute_Name
=> Name_First
,
3283 Prefix
=> New_Reference_To
(Derived_Type
, Loc
));
3284 Set_Etype
(Lo
, Derived_Type
);
3287 Make_Attribute_Reference
(Loc
,
3288 Attribute_Name
=> Name_Last
,
3289 Prefix
=> New_Reference_To
(Derived_Type
, Loc
));
3290 Set_Etype
(Hi
, Derived_Type
);
3292 Set_Scalar_Range
(Derived_Type
,
3299 -- If a constraint is present, analyze the bounds to catch
3300 -- premature usage of the derived literals.
3302 if Nkind
(Indic
) = N_Subtype_Indication
3303 and then Nkind
(Range_Expression
(Constraint
(Indic
))) = N_Range
3305 Analyze
(Low_Bound
(Range_Expression
(Constraint
(Indic
))));
3306 Analyze
(High_Bound
(Range_Expression
(Constraint
(Indic
))));
3309 -- Introduce an implicit base type for the derived type even
3310 -- if there is no constraint attached to it, since this seems
3311 -- closer to the Ada semantics. Build a full type declaration
3312 -- tree for the derived type using the implicit base type as
3313 -- the defining identifier. The build a subtype declaration
3314 -- tree which applies the constraint (if any) have it replace
3315 -- the derived type declaration.
3317 Literal
:= First_Literal
(Parent_Type
);
3318 Literals_List
:= New_List
;
3320 while Present
(Literal
)
3321 and then Ekind
(Literal
) = E_Enumeration_Literal
3323 -- Literals of the derived type have the same representation as
3324 -- those of the parent type, but this representation can be
3325 -- overridden by an explicit representation clause. Indicate
3326 -- that there is no explicit representation given yet. These
3327 -- derived literals are implicit operations of the new type,
3328 -- and can be overriden by explicit ones.
3330 if Nkind
(Literal
) = N_Defining_Character_Literal
then
3332 Make_Defining_Character_Literal
(Loc
, Chars
(Literal
));
3334 New_Lit
:= Make_Defining_Identifier
(Loc
, Chars
(Literal
));
3337 Set_Ekind
(New_Lit
, E_Enumeration_Literal
);
3338 Set_Enumeration_Pos
(New_Lit
, Enumeration_Pos
(Literal
));
3339 Set_Enumeration_Rep
(New_Lit
, Enumeration_Rep
(Literal
));
3340 Set_Enumeration_Rep_Expr
(New_Lit
, Empty
);
3341 Set_Alias
(New_Lit
, Literal
);
3342 Set_Is_Known_Valid
(New_Lit
, True);
3344 Append
(New_Lit
, Literals_List
);
3345 Next_Literal
(Literal
);
3349 Make_Defining_Identifier
(Sloc
(Derived_Type
),
3350 New_External_Name
(Chars
(Derived_Type
), 'B'));
3352 -- Indicate the proper nature of the derived type. This must
3353 -- be done before analysis of the literals, to recognize cases
3354 -- when a literal may be hidden by a previous explicit function
3355 -- definition (cf. c83031a).
3357 Set_Ekind
(Derived_Type
, E_Enumeration_Subtype
);
3358 Set_Etype
(Derived_Type
, Implicit_Base
);
3361 Make_Full_Type_Declaration
(Loc
,
3362 Defining_Identifier
=> Implicit_Base
,
3363 Discriminant_Specifications
=> No_List
,
3365 Make_Enumeration_Type_Definition
(Loc
, Literals_List
));
3367 Mark_Rewrite_Insertion
(Type_Decl
);
3368 Insert_Before
(N
, Type_Decl
);
3369 Analyze
(Type_Decl
);
3371 -- After the implicit base is analyzed its Etype needs to be
3372 -- changed to reflect the fact that it is derived from the
3373 -- parent type which was ignored during analysis. We also set
3374 -- the size at this point.
3376 Set_Etype
(Implicit_Base
, Parent_Type
);
3378 Set_Size_Info
(Implicit_Base
, Parent_Type
);
3379 Set_RM_Size
(Implicit_Base
, RM_Size
(Parent_Type
));
3380 Set_First_Rep_Item
(Implicit_Base
, First_Rep_Item
(Parent_Type
));
3382 Set_Has_Non_Standard_Rep
3383 (Implicit_Base
, Has_Non_Standard_Rep
3385 Set_Has_Delayed_Freeze
(Implicit_Base
);
3387 -- Process the subtype indication including a validation check
3388 -- on the constraint, if any. If a constraint is given, its bounds
3389 -- must be implicitly converted to the new type.
3391 if Nkind
(Indic
) = N_Subtype_Indication
then
3394 R
: constant Node_Id
:=
3395 Range_Expression
(Constraint
(Indic
));
3398 if Nkind
(R
) = N_Range
then
3399 Hi
:= Build_Scalar_Bound
3400 (High_Bound
(R
), Parent_Type
, Implicit_Base
);
3401 Lo
:= Build_Scalar_Bound
3402 (Low_Bound
(R
), Parent_Type
, Implicit_Base
);
3405 -- Constraint is a Range attribute. Replace with the
3406 -- explicit mention of the bounds of the prefix, which
3407 -- must be a subtype.
3409 Analyze
(Prefix
(R
));
3411 Convert_To
(Implicit_Base
,
3412 Make_Attribute_Reference
(Loc
,
3413 Attribute_Name
=> Name_Last
,
3415 New_Occurrence_Of
(Entity
(Prefix
(R
)), Loc
)));
3418 Convert_To
(Implicit_Base
,
3419 Make_Attribute_Reference
(Loc
,
3420 Attribute_Name
=> Name_First
,
3422 New_Occurrence_Of
(Entity
(Prefix
(R
)), Loc
)));
3430 (Type_High_Bound
(Parent_Type
),
3431 Parent_Type
, Implicit_Base
);
3434 (Type_Low_Bound
(Parent_Type
),
3435 Parent_Type
, Implicit_Base
);
3443 -- If we constructed a default range for the case where no range
3444 -- was given, then the expressions in the range must not freeze
3445 -- since they do not correspond to expressions in the source.
3447 if Nkind
(Indic
) /= N_Subtype_Indication
then
3448 Set_Must_Not_Freeze
(Lo
);
3449 Set_Must_Not_Freeze
(Hi
);
3450 Set_Must_Not_Freeze
(Rang_Expr
);
3454 Make_Subtype_Declaration
(Loc
,
3455 Defining_Identifier
=> Derived_Type
,
3456 Subtype_Indication
=>
3457 Make_Subtype_Indication
(Loc
,
3458 Subtype_Mark
=> New_Occurrence_Of
(Implicit_Base
, Loc
),
3460 Make_Range_Constraint
(Loc
,
3461 Range_Expression
=> Rang_Expr
))));
3465 -- If pragma Discard_Names applies on the first subtype
3466 -- of the parent type, then it must be applied on this
3469 if Einfo
.Discard_Names
(First_Subtype
(Parent_Type
)) then
3470 Set_Discard_Names
(Derived_Type
);
3473 -- Apply a range check. Since this range expression doesn't
3474 -- have an Etype, we have to specifically pass the Source_Typ
3475 -- parameter. Is this right???
3477 if Nkind
(Indic
) = N_Subtype_Indication
then
3478 Apply_Range_Check
(Range_Expression
(Constraint
(Indic
)),
3480 Source_Typ
=> Entity
(Subtype_Mark
(Indic
)));
3483 end Build_Derived_Enumeration_Type
;
3485 --------------------------------
3486 -- Build_Derived_Numeric_Type --
3487 --------------------------------
3489 procedure Build_Derived_Numeric_Type
3491 Parent_Type
: Entity_Id
;
3492 Derived_Type
: Entity_Id
)
3494 Loc
: constant Source_Ptr
:= Sloc
(N
);
3495 Tdef
: constant Node_Id
:= Type_Definition
(N
);
3496 Indic
: constant Node_Id
:= Subtype_Indication
(Tdef
);
3497 Parent_Base
: constant Entity_Id
:= Base_Type
(Parent_Type
);
3498 No_Constraint
: constant Boolean := Nkind
(Indic
) /=
3499 N_Subtype_Indication
;
3500 Implicit_Base
: Entity_Id
;
3506 -- Process the subtype indication including a validation check on
3507 -- the constraint if any.
3509 Discard_Node
(Process_Subtype
(Indic
, N
));
3511 -- Introduce an implicit base type for the derived type even if
3512 -- there is no constraint attached to it, since this seems closer
3513 -- to the Ada semantics.
3516 Create_Itype
(Ekind
(Parent_Base
), N
, Derived_Type
, 'B');
3518 Set_Etype
(Implicit_Base
, Parent_Base
);
3519 Set_Ekind
(Implicit_Base
, Ekind
(Parent_Base
));
3520 Set_Size_Info
(Implicit_Base
, Parent_Base
);
3521 Set_RM_Size
(Implicit_Base
, RM_Size
(Parent_Base
));
3522 Set_First_Rep_Item
(Implicit_Base
, First_Rep_Item
(Parent_Base
));
3523 Set_Parent
(Implicit_Base
, Parent
(Derived_Type
));
3525 if Is_Discrete_Or_Fixed_Point_Type
(Parent_Base
) then
3526 Set_RM_Size
(Implicit_Base
, RM_Size
(Parent_Base
));
3529 Set_Has_Delayed_Freeze
(Implicit_Base
);
3531 Lo
:= New_Copy_Tree
(Type_Low_Bound
(Parent_Base
));
3532 Hi
:= New_Copy_Tree
(Type_High_Bound
(Parent_Base
));
3534 Set_Scalar_Range
(Implicit_Base
,
3539 if Has_Infinities
(Parent_Base
) then
3540 Set_Includes_Infinities
(Scalar_Range
(Implicit_Base
));
3543 -- The Derived_Type, which is the entity of the declaration, is
3544 -- a subtype of the implicit base. Its Ekind is a subtype, even
3545 -- in the absence of an explicit constraint.
3547 Set_Etype
(Derived_Type
, Implicit_Base
);
3549 -- If we did not have a constraint, then the Ekind is set from the
3550 -- parent type (otherwise Process_Subtype has set the bounds)
3552 if No_Constraint
then
3553 Set_Ekind
(Derived_Type
, Subtype_Kind
(Ekind
(Parent_Type
)));
3556 -- If we did not have a range constraint, then set the range
3557 -- from the parent type. Otherwise, the call to Process_Subtype
3558 -- has set the bounds.
3561 or else not Has_Range_Constraint
(Indic
)
3563 Set_Scalar_Range
(Derived_Type
,
3565 Low_Bound
=> New_Copy_Tree
(Type_Low_Bound
(Parent_Type
)),
3566 High_Bound
=> New_Copy_Tree
(Type_High_Bound
(Parent_Type
))));
3567 Set_Is_Constrained
(Derived_Type
, Is_Constrained
(Parent_Type
));
3569 if Has_Infinities
(Parent_Type
) then
3570 Set_Includes_Infinities
(Scalar_Range
(Derived_Type
));
3574 -- Set remaining type-specific fields, depending on numeric type
3576 if Is_Modular_Integer_Type
(Parent_Type
) then
3577 Set_Modulus
(Implicit_Base
, Modulus
(Parent_Base
));
3579 Set_Non_Binary_Modulus
3580 (Implicit_Base
, Non_Binary_Modulus
(Parent_Base
));
3582 elsif Is_Floating_Point_Type
(Parent_Type
) then
3584 -- Digits of base type is always copied from the digits value of
3585 -- the parent base type, but the digits of the derived type will
3586 -- already have been set if there was a constraint present.
3588 Set_Digits_Value
(Implicit_Base
, Digits_Value
(Parent_Base
));
3589 Set_Vax_Float
(Implicit_Base
, Vax_Float
(Parent_Base
));
3591 if No_Constraint
then
3592 Set_Digits_Value
(Derived_Type
, Digits_Value
(Parent_Type
));
3595 elsif Is_Fixed_Point_Type
(Parent_Type
) then
3597 -- Small of base type and derived type are always copied from
3598 -- the parent base type, since smalls never change. The delta
3599 -- of the base type is also copied from the parent base type.
3600 -- However the delta of the derived type will have been set
3601 -- already if a constraint was present.
3603 Set_Small_Value
(Derived_Type
, Small_Value
(Parent_Base
));
3604 Set_Small_Value
(Implicit_Base
, Small_Value
(Parent_Base
));
3605 Set_Delta_Value
(Implicit_Base
, Delta_Value
(Parent_Base
));
3607 if No_Constraint
then
3608 Set_Delta_Value
(Derived_Type
, Delta_Value
(Parent_Type
));
3611 -- The scale and machine radix in the decimal case are always
3612 -- copied from the parent base type.
3614 if Is_Decimal_Fixed_Point_Type
(Parent_Type
) then
3615 Set_Scale_Value
(Derived_Type
, Scale_Value
(Parent_Base
));
3616 Set_Scale_Value
(Implicit_Base
, Scale_Value
(Parent_Base
));
3618 Set_Machine_Radix_10
3619 (Derived_Type
, Machine_Radix_10
(Parent_Base
));
3620 Set_Machine_Radix_10
3621 (Implicit_Base
, Machine_Radix_10
(Parent_Base
));
3623 Set_Digits_Value
(Implicit_Base
, Digits_Value
(Parent_Base
));
3625 if No_Constraint
then
3626 Set_Digits_Value
(Derived_Type
, Digits_Value
(Parent_Base
));
3629 -- the analysis of the subtype_indication sets the
3630 -- digits value of the derived type.
3637 -- The type of the bounds is that of the parent type, and they
3638 -- must be converted to the derived type.
3640 Convert_Scalar_Bounds
(N
, Parent_Type
, Derived_Type
, Loc
);
3642 -- The implicit_base should be frozen when the derived type is frozen,
3643 -- but note that it is used in the conversions of the bounds. For
3644 -- fixed types we delay the determination of the bounds until the proper
3645 -- freezing point. For other numeric types this is rejected by GCC, for
3646 -- reasons that are currently unclear (???), so we choose to freeze the
3647 -- implicit base now. In the case of integers and floating point types
3648 -- this is harmless because subsequent representation clauses cannot
3649 -- affect anything, but it is still baffling that we cannot use the
3650 -- same mechanism for all derived numeric types.
3652 if Is_Fixed_Point_Type
(Parent_Type
) then
3653 Conditional_Delay
(Implicit_Base
, Parent_Type
);
3655 Freeze_Before
(N
, Implicit_Base
);
3657 end Build_Derived_Numeric_Type
;
3659 --------------------------------
3660 -- Build_Derived_Private_Type --
3661 --------------------------------
3663 procedure Build_Derived_Private_Type
3665 Parent_Type
: Entity_Id
;
3666 Derived_Type
: Entity_Id
;
3667 Is_Completion
: Boolean;
3668 Derive_Subps
: Boolean := True)
3670 Der_Base
: Entity_Id
;
3672 Full_Decl
: Node_Id
:= Empty
;
3673 Full_Der
: Entity_Id
;
3675 Last_Discr
: Entity_Id
;
3676 Par_Scope
: constant Entity_Id
:= Scope
(Base_Type
(Parent_Type
));
3677 Swapped
: Boolean := False;
3679 procedure Copy_And_Build
;
3680 -- Copy derived type declaration, replace parent with its full view,
3681 -- and analyze new declaration.
3683 --------------------
3684 -- Copy_And_Build --
3685 --------------------
3687 procedure Copy_And_Build
is
3691 if Ekind
(Parent_Type
) in Record_Kind
3692 or else (Ekind
(Parent_Type
) in Enumeration_Kind
3693 and then Root_Type
(Parent_Type
) /= Standard_Character
3694 and then Root_Type
(Parent_Type
) /= Standard_Wide_Character
3695 and then not Is_Generic_Type
(Root_Type
(Parent_Type
)))
3697 Full_N
:= New_Copy_Tree
(N
);
3698 Insert_After
(N
, Full_N
);
3699 Build_Derived_Type
(
3700 Full_N
, Parent_Type
, Full_Der
, True, Derive_Subps
=> False);
3703 Build_Derived_Type
(
3704 N
, Parent_Type
, Full_Der
, True, Derive_Subps
=> False);
3708 -- Start of processing for Build_Derived_Private_Type
3711 if Is_Tagged_Type
(Parent_Type
) then
3712 Build_Derived_Record_Type
3713 (N
, Parent_Type
, Derived_Type
, Derive_Subps
);
3716 elsif Has_Discriminants
(Parent_Type
) then
3718 if Present
(Full_View
(Parent_Type
)) then
3719 if not Is_Completion
then
3721 -- Copy declaration for subsequent analysis, to
3722 -- provide a completion for what is a private
3725 Full_Decl
:= New_Copy_Tree
(N
);
3726 Full_Der
:= New_Copy
(Derived_Type
);
3728 Insert_After
(N
, Full_Decl
);
3731 -- If this is a completion, the full view being built is
3732 -- itself private. We build a subtype of the parent with
3733 -- the same constraints as this full view, to convey to the
3734 -- back end the constrained components and the size of this
3735 -- subtype. If the parent is constrained, its full view can
3736 -- serve as the underlying full view of the derived type.
3738 if No
(Discriminant_Specifications
(N
)) then
3740 if Nkind
(Subtype_Indication
(Type_Definition
(N
)))
3741 = N_Subtype_Indication
3743 Build_Underlying_Full_View
(N
, Derived_Type
, Parent_Type
);
3745 elsif Is_Constrained
(Full_View
(Parent_Type
)) then
3746 Set_Underlying_Full_View
(Derived_Type
,
3747 Full_View
(Parent_Type
));
3751 -- If there are new discriminants, the parent subtype is
3752 -- constrained by them, but it is not clear how to build
3753 -- the underlying_full_view in this case ???
3760 -- Build partial view of derived type from partial view of parent.
3762 Build_Derived_Record_Type
3763 (N
, Parent_Type
, Derived_Type
, Derive_Subps
);
3765 if Present
(Full_View
(Parent_Type
))
3766 and then not Is_Completion
3768 if not In_Open_Scopes
(Par_Scope
)
3769 or else not In_Same_Source_Unit
(N
, Parent_Type
)
3771 -- Swap partial and full views temporarily
3773 Install_Private_Declarations
(Par_Scope
);
3774 Install_Visible_Declarations
(Par_Scope
);
3778 -- Build full view of derived type from full view of
3779 -- parent which is now installed.
3780 -- Subprograms have been derived on the partial view,
3781 -- the completion does not derive them anew.
3783 if not Is_Tagged_Type
(Parent_Type
) then
3784 Build_Derived_Record_Type
3785 (Full_Decl
, Parent_Type
, Full_Der
, False);
3788 -- If full view of parent is tagged, the completion
3789 -- inherits the proper primitive operations.
3791 Set_Defining_Identifier
(Full_Decl
, Full_Der
);
3792 Build_Derived_Record_Type
3793 (Full_Decl
, Parent_Type
, Full_Der
, Derive_Subps
);
3794 Set_Analyzed
(Full_Decl
);
3798 Uninstall_Declarations
(Par_Scope
);
3800 if In_Open_Scopes
(Par_Scope
) then
3801 Install_Visible_Declarations
(Par_Scope
);
3805 Der_Base
:= Base_Type
(Derived_Type
);
3806 Set_Full_View
(Derived_Type
, Full_Der
);
3807 Set_Full_View
(Der_Base
, Base_Type
(Full_Der
));
3809 -- Copy the discriminant list from full view to
3810 -- the partial views (base type and its subtype).
3811 -- Gigi requires that the partial and full views
3812 -- have the same discriminants.
3813 -- ??? Note that since the partial view is pointing
3814 -- to discriminants in the full view, their scope
3815 -- will be that of the full view. This might
3816 -- cause some front end problems and need
3819 Discr
:= First_Discriminant
(Base_Type
(Full_Der
));
3820 Set_First_Entity
(Der_Base
, Discr
);
3823 Last_Discr
:= Discr
;
3824 Next_Discriminant
(Discr
);
3825 exit when No
(Discr
);
3828 Set_Last_Entity
(Der_Base
, Last_Discr
);
3830 Set_First_Entity
(Derived_Type
, First_Entity
(Der_Base
));
3831 Set_Last_Entity
(Derived_Type
, Last_Entity
(Der_Base
));
3834 -- If this is a completion, the derived type stays private
3835 -- and there is no need to create a further full view, except
3836 -- in the unusual case when the derivation is nested within a
3837 -- child unit, see below.
3842 elsif Present
(Full_View
(Parent_Type
))
3843 and then Has_Discriminants
(Full_View
(Parent_Type
))
3845 if Has_Unknown_Discriminants
(Parent_Type
)
3846 and then Nkind
(Subtype_Indication
(Type_Definition
(N
)))
3847 = N_Subtype_Indication
3850 ("cannot constrain type with unknown discriminants",
3851 Subtype_Indication
(Type_Definition
(N
)));
3855 -- If full view of parent is a record type, Build full view as
3856 -- a derivation from the parent's full view. Partial view remains
3857 -- private. For code generation and linking, the full view must
3858 -- have the same public status as the partial one. This full view
3859 -- is only needed if the parent type is in an enclosing scope, so
3860 -- that the full view may actually become visible, e.g. in a child
3861 -- unit. This is both more efficient, and avoids order of freezing
3862 -- problems with the added entities.
3864 if not Is_Private_Type
(Full_View
(Parent_Type
))
3865 and then (In_Open_Scopes
(Scope
(Parent_Type
)))
3867 Full_Der
:= Make_Defining_Identifier
(Sloc
(Derived_Type
),
3868 Chars
(Derived_Type
));
3869 Set_Is_Itype
(Full_Der
);
3870 Set_Has_Private_Declaration
(Full_Der
);
3871 Set_Has_Private_Declaration
(Derived_Type
);
3872 Set_Associated_Node_For_Itype
(Full_Der
, N
);
3873 Set_Parent
(Full_Der
, Parent
(Derived_Type
));
3874 Set_Full_View
(Derived_Type
, Full_Der
);
3875 Set_Is_Public
(Full_Der
, Is_Public
(Derived_Type
));
3876 Full_P
:= Full_View
(Parent_Type
);
3877 Exchange_Declarations
(Parent_Type
);
3879 Exchange_Declarations
(Full_P
);
3882 Build_Derived_Record_Type
3883 (N
, Full_View
(Parent_Type
), Derived_Type
,
3884 Derive_Subps
=> False);
3887 -- In any case, the primitive operations are inherited from
3888 -- the parent type, not from the internal full view.
3890 Set_Etype
(Base_Type
(Derived_Type
), Base_Type
(Parent_Type
));
3892 if Derive_Subps
then
3893 Derive_Subprograms
(Parent_Type
, Derived_Type
);
3897 -- Untagged type, No discriminants on either view
3899 if Nkind
(Subtype_Indication
(Type_Definition
(N
)))
3900 = N_Subtype_Indication
3903 ("illegal constraint on type without discriminants", N
);
3906 if Present
(Discriminant_Specifications
(N
))
3907 and then Present
(Full_View
(Parent_Type
))
3908 and then not Is_Tagged_Type
(Full_View
(Parent_Type
))
3911 ("cannot add discriminants to untagged type", N
);
3914 Set_Stored_Constraint
(Derived_Type
, No_Elist
);
3915 Set_Is_Constrained
(Derived_Type
, Is_Constrained
(Parent_Type
));
3916 Set_Is_Controlled
(Derived_Type
, Is_Controlled
(Parent_Type
));
3917 Set_Has_Controlled_Component
3918 (Derived_Type
, Has_Controlled_Component
3921 -- Direct controlled types do not inherit Finalize_Storage_Only flag
3923 if not Is_Controlled
(Parent_Type
) then
3924 Set_Finalize_Storage_Only
3925 (Base_Type
(Derived_Type
), Finalize_Storage_Only
(Parent_Type
));
3928 -- Construct the implicit full view by deriving from full
3929 -- view of the parent type. In order to get proper visibility,
3930 -- we install the parent scope and its declarations.
3932 -- ??? if the parent is untagged private and its
3933 -- completion is tagged, this mechanism will not
3934 -- work because we cannot derive from the tagged
3935 -- full view unless we have an extension
3937 if Present
(Full_View
(Parent_Type
))
3938 and then not Is_Tagged_Type
(Full_View
(Parent_Type
))
3939 and then not Is_Completion
3941 Full_Der
:= Make_Defining_Identifier
(Sloc
(Derived_Type
),
3942 Chars
(Derived_Type
));
3943 Set_Is_Itype
(Full_Der
);
3944 Set_Has_Private_Declaration
(Full_Der
);
3945 Set_Has_Private_Declaration
(Derived_Type
);
3946 Set_Associated_Node_For_Itype
(Full_Der
, N
);
3947 Set_Parent
(Full_Der
, Parent
(Derived_Type
));
3948 Set_Full_View
(Derived_Type
, Full_Der
);
3950 if not In_Open_Scopes
(Par_Scope
) then
3951 Install_Private_Declarations
(Par_Scope
);
3952 Install_Visible_Declarations
(Par_Scope
);
3954 Uninstall_Declarations
(Par_Scope
);
3956 -- If parent scope is open and in another unit, and
3957 -- parent has a completion, then the derivation is taking
3958 -- place in the visible part of a child unit. In that
3959 -- case retrieve the full view of the parent momentarily.
3961 elsif not In_Same_Source_Unit
(N
, Parent_Type
) then
3962 Full_P
:= Full_View
(Parent_Type
);
3963 Exchange_Declarations
(Parent_Type
);
3965 Exchange_Declarations
(Full_P
);
3967 -- Otherwise it is a local derivation.
3973 Set_Scope
(Full_Der
, Current_Scope
);
3974 Set_Is_First_Subtype
(Full_Der
,
3975 Is_First_Subtype
(Derived_Type
));
3976 Set_Has_Size_Clause
(Full_Der
, False);
3977 Set_Has_Alignment_Clause
(Full_Der
, False);
3978 Set_Next_Entity
(Full_Der
, Empty
);
3979 Set_Has_Delayed_Freeze
(Full_Der
);
3980 Set_Is_Frozen
(Full_Der
, False);
3981 Set_Freeze_Node
(Full_Der
, Empty
);
3982 Set_Depends_On_Private
(Full_Der
,
3983 Has_Private_Component
(Full_Der
));
3984 Set_Public_Status
(Full_Der
);
3988 Set_Has_Unknown_Discriminants
(Derived_Type
,
3989 Has_Unknown_Discriminants
(Parent_Type
));
3991 if Is_Private_Type
(Derived_Type
) then
3992 Set_Private_Dependents
(Derived_Type
, New_Elmt_List
);
3995 if Is_Private_Type
(Parent_Type
)
3996 and then Base_Type
(Parent_Type
) = Parent_Type
3997 and then In_Open_Scopes
(Scope
(Parent_Type
))
3999 Append_Elmt
(Derived_Type
, Private_Dependents
(Parent_Type
));
4001 if Is_Child_Unit
(Scope
(Current_Scope
))
4002 and then Is_Completion
4003 and then In_Private_Part
(Current_Scope
)
4004 and then Scope
(Parent_Type
) /= Current_Scope
4006 -- This is the unusual case where a type completed by a private
4007 -- derivation occurs within a package nested in a child unit,
4008 -- and the parent is declared in an ancestor. In this case, the
4009 -- full view of the parent type will become visible in the body
4010 -- of the enclosing child, and only then will the current type
4011 -- be possibly non-private. We build a underlying full view that
4012 -- will be installed when the enclosing child body is compiled.
4015 IR
: constant Node_Id
:= Make_Itype_Reference
(Sloc
(N
));
4019 Make_Defining_Identifier
(Sloc
(Derived_Type
),
4020 Chars
(Derived_Type
));
4021 Set_Is_Itype
(Full_Der
);
4022 Set_Itype
(IR
, Full_Der
);
4023 Insert_After
(N
, IR
);
4025 -- The full view will be used to swap entities on entry/exit
4026 -- to the body, and must appear in the entity list for the
4029 Append_Entity
(Full_Der
, Scope
(Derived_Type
));
4030 Set_Has_Private_Declaration
(Full_Der
);
4031 Set_Has_Private_Declaration
(Derived_Type
);
4032 Set_Associated_Node_For_Itype
(Full_Der
, N
);
4033 Set_Parent
(Full_Der
, Parent
(Derived_Type
));
4034 Full_P
:= Full_View
(Parent_Type
);
4035 Exchange_Declarations
(Parent_Type
);
4037 Exchange_Declarations
(Full_P
);
4038 Set_Underlying_Full_View
(Derived_Type
, Full_Der
);
4042 end Build_Derived_Private_Type
;
4044 -------------------------------
4045 -- Build_Derived_Record_Type --
4046 -------------------------------
4050 -- Ideally we would like to use the same model of type derivation for
4051 -- tagged and untagged record types. Unfortunately this is not quite
4052 -- possible because the semantics of representation clauses is different
4053 -- for tagged and untagged records under inheritance. Consider the
4056 -- type R (...) is [tagged] record ... end record;
4057 -- type T (...) is new R (...) [with ...];
4059 -- The representation clauses of T can specify a completely different
4060 -- record layout from R's. Hence the same component can be placed in
4061 -- two very different positions in objects of type T and R. If R and T
4062 -- are tagged types, representation clauses for T can only specify the
4063 -- layout of non inherited components, thus components that are common
4064 -- in R and T have the same position in objects of type R and T.
4066 -- This has two implications. The first is that the entire tree for R's
4067 -- declaration needs to be copied for T in the untagged case, so that
4068 -- T can be viewed as a record type of its own with its own representation
4069 -- clauses. The second implication is the way we handle discriminants.
4070 -- Specifically, in the untagged case we need a way to communicate to Gigi
4071 -- what are the real discriminants in the record, while for the semantics
4072 -- we need to consider those introduced by the user to rename the
4073 -- discriminants in the parent type. This is handled by introducing the
4074 -- notion of stored discriminants. See below for more.
4076 -- Fortunately the way regular components are inherited can be handled in
4077 -- the same way in tagged and untagged types.
4079 -- To complicate things a bit more the private view of a private extension
4080 -- cannot be handled in the same way as the full view (for one thing the
4081 -- semantic rules are somewhat different). We will explain what differs
4084 -- 2. DISCRIMINANTS UNDER INHERITANCE.
4086 -- The semantic rules governing the discriminants of derived types are
4089 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
4090 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
4092 -- If parent type has discriminants, then the discriminants that are
4093 -- declared in the derived type are [3.4 (11)]:
4095 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
4098 -- o Otherwise, each discriminant of the parent type (implicitly
4099 -- declared in the same order with the same specifications). In this
4100 -- case, the discriminants are said to be "inherited", or if unknown in
4101 -- the parent are also unknown in the derived type.
4103 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
4105 -- o The parent subtype shall be constrained;
4107 -- o If the parent type is not a tagged type, then each discriminant of
4108 -- the derived type shall be used in the constraint defining a parent
4109 -- subtype [Implementation note: this ensures that the new discriminant
4110 -- can share storage with an existing discriminant.].
4112 -- For the derived type each discriminant of the parent type is either
4113 -- inherited, constrained to equal some new discriminant of the derived
4114 -- type, or constrained to the value of an expression.
4116 -- When inherited or constrained to equal some new discriminant, the
4117 -- parent discriminant and the discriminant of the derived type are said
4120 -- If a discriminant of the parent type is constrained to a specific value
4121 -- in the derived type definition, then the discriminant is said to be
4122 -- "specified" by that derived type definition.
4124 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES.
4126 -- We have spoken about stored discriminants in point 1 (introduction)
4127 -- above. There are two sort of stored discriminants: implicit and
4128 -- explicit. As long as the derived type inherits the same discriminants as
4129 -- the root record type, stored discriminants are the same as regular
4130 -- discriminants, and are said to be implicit. However, if any discriminant
4131 -- in the root type was renamed in the derived type, then the derived
4132 -- type will contain explicit stored discriminants. Explicit stored
4133 -- discriminants are discriminants in addition to the semantically visible
4134 -- discriminants defined for the derived type. Stored discriminants are
4135 -- used by Gigi to figure out what are the physical discriminants in
4136 -- objects of the derived type (see precise definition in einfo.ads).
4137 -- As an example, consider the following:
4139 -- type R (D1, D2, D3 : Int) is record ... end record;
4140 -- type T1 is new R;
4141 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
4142 -- type T3 is new T2;
4143 -- type T4 (Y : Int) is new T3 (Y, 99);
4145 -- The following table summarizes the discriminants and stored
4146 -- discriminants in R and T1 through T4.
4148 -- Type Discrim Stored Discrim Comment
4149 -- R (D1, D2, D3) (D1, D2, D3) Gider discrims are implicit in R
4150 -- T1 (D1, D2, D3) (D1, D2, D3) Gider discrims are implicit in T1
4151 -- T2 (X1, X2) (D1, D2, D3) Gider discrims are EXPLICIT in T2
4152 -- T3 (X1, X2) (D1, D2, D3) Gider discrims are EXPLICIT in T3
4153 -- T4 (Y) (D1, D2, D3) Gider discrims are EXPLICIT in T4
4155 -- Field Corresponding_Discriminant (abbreviated CD below) allows to find
4156 -- the corresponding discriminant in the parent type, while
4157 -- Original_Record_Component (abbreviated ORC below), the actual physical
4158 -- component that is renamed. Finally the field Is_Completely_Hidden
4159 -- (abbreviated ICH below) is set for all explicit stored discriminants
4160 -- (see einfo.ads for more info). For the above example this gives:
4162 -- Discrim CD ORC ICH
4163 -- ^^^^^^^ ^^ ^^^ ^^^
4164 -- D1 in R empty itself no
4165 -- D2 in R empty itself no
4166 -- D3 in R empty itself no
4168 -- D1 in T1 D1 in R itself no
4169 -- D2 in T1 D2 in R itself no
4170 -- D3 in T1 D3 in R itself no
4172 -- X1 in T2 D3 in T1 D3 in T2 no
4173 -- X2 in T2 D1 in T1 D1 in T2 no
4174 -- D1 in T2 empty itself yes
4175 -- D2 in T2 empty itself yes
4176 -- D3 in T2 empty itself yes
4178 -- X1 in T3 X1 in T2 D3 in T3 no
4179 -- X2 in T3 X2 in T2 D1 in T3 no
4180 -- D1 in T3 empty itself yes
4181 -- D2 in T3 empty itself yes
4182 -- D3 in T3 empty itself yes
4184 -- Y in T4 X1 in T3 D3 in T3 no
4185 -- D1 in T3 empty itself yes
4186 -- D2 in T3 empty itself yes
4187 -- D3 in T3 empty itself yes
4189 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES.
4191 -- Type derivation for tagged types is fairly straightforward. if no
4192 -- discriminants are specified by the derived type, these are inherited
4193 -- from the parent. No explicit stored discriminants are ever necessary.
4194 -- The only manipulation that is done to the tree is that of adding a
4195 -- _parent field with parent type and constrained to the same constraint
4196 -- specified for the parent in the derived type definition. For instance:
4198 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
4199 -- type T1 is new R with null record;
4200 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
4202 -- are changed into :
4204 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
4205 -- _parent : R (D1, D2, D3);
4208 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
4209 -- _parent : T1 (X2, 88, X1);
4212 -- The discriminants actually present in R, T1 and T2 as well as their CD,
4213 -- ORC and ICH fields are:
4215 -- Discrim CD ORC ICH
4216 -- ^^^^^^^ ^^ ^^^ ^^^
4217 -- D1 in R empty itself no
4218 -- D2 in R empty itself no
4219 -- D3 in R empty itself no
4221 -- D1 in T1 D1 in R D1 in R no
4222 -- D2 in T1 D2 in R D2 in R no
4223 -- D3 in T1 D3 in R D3 in R no
4225 -- X1 in T2 D3 in T1 D3 in R no
4226 -- X2 in T2 D1 in T1 D1 in R no
4228 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS.
4230 -- Regardless of whether we dealing with a tagged or untagged type
4231 -- we will transform all derived type declarations of the form
4233 -- type T is new R (...) [with ...];
4235 -- subtype S is R (...);
4236 -- type T is new S [with ...];
4238 -- type BT is new R [with ...];
4239 -- subtype T is BT (...);
4241 -- That is, the base derived type is constrained only if it has no
4242 -- discriminants. The reason for doing this is that GNAT's semantic model
4243 -- assumes that a base type with discriminants is unconstrained.
4245 -- Note that, strictly speaking, the above transformation is not always
4246 -- correct. Consider for instance the following excerpt from ACVC b34011a:
4248 -- procedure B34011A is
4249 -- type REC (D : integer := 0) is record
4254 -- type T6 is new Rec;
4255 -- function F return T6;
4260 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
4263 -- The definition of Q6.U is illegal. However transforming Q6.U into
4265 -- type BaseU is new T6;
4266 -- subtype U is BaseU (Q6.F.I)
4268 -- turns U into a legal subtype, which is incorrect. To avoid this problem
4269 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
4270 -- the transformation described above.
4272 -- There is another instance where the above transformation is incorrect.
4276 -- type Base (D : Integer) is tagged null record;
4277 -- procedure P (X : Base);
4279 -- type Der is new Base (2) with null record;
4280 -- procedure P (X : Der);
4283 -- Then the above transformation turns this into
4285 -- type Der_Base is new Base with null record;
4286 -- -- procedure P (X : Base) is implicitly inherited here
4287 -- -- as procedure P (X : Der_Base).
4289 -- subtype Der is Der_Base (2);
4290 -- procedure P (X : Der);
4291 -- -- The overriding of P (X : Der_Base) is illegal since we
4292 -- -- have a parameter conformance problem.
4294 -- To get around this problem, after having semantically processed Der_Base
4295 -- and the rewritten subtype declaration for Der, we copy Der_Base field
4296 -- Discriminant_Constraint from Der so that when parameter conformance is
4297 -- checked when P is overridden, no semantic errors are flagged.
4299 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS.
4301 -- Regardless of whether we are dealing with a tagged or untagged type
4302 -- we will transform all derived type declarations of the form
4304 -- type R (D1, .., Dn : ...) is [tagged] record ...;
4305 -- type T is new R [with ...];
4307 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
4309 -- The reason for such transformation is that it allows us to implement a
4310 -- very clean form of component inheritance as explained below.
4312 -- Note that this transformation is not achieved by direct tree rewriting
4313 -- and manipulation, but rather by redoing the semantic actions that the
4314 -- above transformation will entail. This is done directly in routine
4315 -- Inherit_Components.
4317 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE.
4319 -- In both tagged and untagged derived types, regular non discriminant
4320 -- components are inherited in the derived type from the parent type. In
4321 -- the absence of discriminants component, inheritance is straightforward
4322 -- as components can simply be copied from the parent.
4323 -- If the parent has discriminants, inheriting components constrained with
4324 -- these discriminants requires caution. Consider the following example:
4326 -- type R (D1, D2 : Positive) is [tagged] record
4327 -- S : String (D1 .. D2);
4330 -- type T1 is new R [with null record];
4331 -- type T2 (X : positive) is new R (1, X) [with null record];
4333 -- As explained in 6. above, T1 is rewritten as
4335 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
4337 -- which makes the treatment for T1 and T2 identical.
4339 -- What we want when inheriting S, is that references to D1 and D2 in R are
4340 -- replaced with references to their correct constraints, ie D1 and D2 in
4341 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
4342 -- with either discriminant references in the derived type or expressions.
4343 -- This replacement is achieved as follows: before inheriting R's
4344 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
4345 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
4346 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
4347 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
4348 -- by String (1 .. X).
4350 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS.
4352 -- We explain here the rules governing private type extensions relevant to
4353 -- type derivation. These rules are explained on the following example:
4355 -- type D [(...)] is new A [(...)] with private; <-- partial view
4356 -- type D [(...)] is new P [(...)] with null record; <-- full view
4358 -- Type A is called the ancestor subtype of the private extension.
4359 -- Type P is the parent type of the full view of the private extension. It
4360 -- must be A or a type derived from A.
4362 -- The rules concerning the discriminants of private type extensions are
4365 -- o If a private extension inherits known discriminants from the ancestor
4366 -- subtype, then the full view shall also inherit its discriminants from
4367 -- the ancestor subtype and the parent subtype of the full view shall be
4368 -- constrained if and only if the ancestor subtype is constrained.
4370 -- o If a partial view has unknown discriminants, then the full view may
4371 -- define a definite or an indefinite subtype, with or without
4374 -- o If a partial view has neither known nor unknown discriminants, then
4375 -- the full view shall define a definite subtype.
4377 -- o If the ancestor subtype of a private extension has constrained
4378 -- discriminants, then the parent subtype of the full view shall impose a
4379 -- statically matching constraint on those discriminants.
4381 -- This means that only the following forms of private extensions are
4384 -- type D is new A with private; <-- partial view
4385 -- type D is new P with null record; <-- full view
4387 -- If A has no discriminants than P has no discriminants, otherwise P must
4388 -- inherit A's discriminants.
4390 -- type D is new A (...) with private; <-- partial view
4391 -- type D is new P (:::) with null record; <-- full view
4393 -- P must inherit A's discriminants and (...) and (:::) must statically
4396 -- subtype A is R (...);
4397 -- type D is new A with private; <-- partial view
4398 -- type D is new P with null record; <-- full view
4400 -- P must have inherited R's discriminants and must be derived from A or
4401 -- any of its subtypes.
4403 -- type D (..) is new A with private; <-- partial view
4404 -- type D (..) is new P [(:::)] with null record; <-- full view
4406 -- No specific constraints on P's discriminants or constraint (:::).
4407 -- Note that A can be unconstrained, but the parent subtype P must either
4408 -- be constrained or (:::) must be present.
4410 -- type D (..) is new A [(...)] with private; <-- partial view
4411 -- type D (..) is new P [(:::)] with null record; <-- full view
4413 -- P's constraints on A's discriminants must statically match those
4414 -- imposed by (...).
4416 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS.
4418 -- The full view of a private extension is handled exactly as described
4419 -- above. The model chose for the private view of a private extension
4420 -- is the same for what concerns discriminants (ie they receive the same
4421 -- treatment as in the tagged case). However, the private view of the
4422 -- private extension always inherits the components of the parent base,
4423 -- without replacing any discriminant reference. Strictly speaking this
4424 -- is incorrect. However, Gigi never uses this view to generate code so
4425 -- this is a purely semantic issue. In theory, a set of transformations
4426 -- similar to those given in 5. and 6. above could be applied to private
4427 -- views of private extensions to have the same model of component
4428 -- inheritance as for non private extensions. However, this is not done
4429 -- because it would further complicate private type processing.
4430 -- Semantically speaking, this leaves us in an uncomfortable
4431 -- situation. As an example consider:
4434 -- type R (D : integer) is tagged record
4435 -- S : String (1 .. D);
4437 -- procedure P (X : R);
4438 -- type T is new R (1) with private;
4440 -- type T is new R (1) with null record;
4443 -- This is transformed into:
4446 -- type R (D : integer) is tagged record
4447 -- S : String (1 .. D);
4449 -- procedure P (X : R);
4450 -- type T is new R (1) with private;
4452 -- type BaseT is new R with null record;
4453 -- subtype T is BaseT (1);
4456 -- (strictly speaking the above is incorrect Ada).
4458 -- From the semantic standpoint the private view of private extension T
4459 -- should be flagged as constrained since one can clearly have
4463 -- in a unit withing Pack. However, when deriving subprograms for the
4464 -- private view of private extension T, T must be seen as unconstrained
4465 -- since T has discriminants (this is a constraint of the current
4466 -- subprogram derivation model). Thus, when processing the private view of
4467 -- a private extension such as T, we first mark T as unconstrained, we
4468 -- process it, we perform program derivation and just before returning from
4469 -- Build_Derived_Record_Type we mark T as constrained.
4470 -- ??? Are there are other uncomfortable cases that we will have to
4473 -- 10. RECORD_TYPE_WITH_PRIVATE complications.
4475 -- Types that are derived from a visible record type and have a private
4476 -- extension present other peculiarities. They behave mostly like private
4477 -- types, but if they have primitive operations defined, these will not
4478 -- have the proper signatures for further inheritance, because other
4479 -- primitive operations will use the implicit base that we define for
4480 -- private derivations below. This affect subprogram inheritance (see
4481 -- Derive_Subprograms for details). We also derive the implicit base from
4482 -- the base type of the full view, so that the implicit base is a record
4483 -- type and not another private type, This avoids infinite loops.
4485 procedure Build_Derived_Record_Type
4487 Parent_Type
: Entity_Id
;
4488 Derived_Type
: Entity_Id
;
4489 Derive_Subps
: Boolean := True)
4491 Loc
: constant Source_Ptr
:= Sloc
(N
);
4492 Parent_Base
: Entity_Id
;
4497 Discrim
: Entity_Id
;
4498 Last_Discrim
: Entity_Id
;
4500 Discs
: Elist_Id
:= New_Elmt_List
;
4501 -- An empty Discs list means that there were no constraints in the
4502 -- subtype indication or that there was an error processing it.
4504 Assoc_List
: Elist_Id
;
4505 New_Discrs
: Elist_Id
;
4507 New_Base
: Entity_Id
;
4509 New_Indic
: Node_Id
;
4511 Is_Tagged
: constant Boolean := Is_Tagged_Type
(Parent_Type
);
4512 Discriminant_Specs
: constant Boolean :=
4513 Present
(Discriminant_Specifications
(N
));
4514 Private_Extension
: constant Boolean :=
4515 (Nkind
(N
) = N_Private_Extension_Declaration
);
4517 Constraint_Present
: Boolean;
4518 Inherit_Discrims
: Boolean := False;
4520 Save_Etype
: Entity_Id
;
4521 Save_Discr_Constr
: Elist_Id
;
4522 Save_Next_Entity
: Entity_Id
;
4525 if Ekind
(Parent_Type
) = E_Record_Type_With_Private
4526 and then Present
(Full_View
(Parent_Type
))
4527 and then Has_Discriminants
(Parent_Type
)
4529 Parent_Base
:= Base_Type
(Full_View
(Parent_Type
));
4531 Parent_Base
:= Base_Type
(Parent_Type
);
4534 -- Before we start the previously documented transformations, here is
4535 -- a little fix for size and alignment of tagged types. Normally when
4536 -- we derive type D from type P, we copy the size and alignment of P
4537 -- as the default for D, and in the absence of explicit representation
4538 -- clauses for D, the size and alignment are indeed the same as the
4541 -- But this is wrong for tagged types, since fields may be added,
4542 -- and the default size may need to be larger, and the default
4543 -- alignment may need to be larger.
4545 -- We therefore reset the size and alignment fields in the tagged
4546 -- case. Note that the size and alignment will in any case be at
4547 -- least as large as the parent type (since the derived type has
4548 -- a copy of the parent type in the _parent field)
4551 Init_Size_Align
(Derived_Type
);
4554 -- STEP 0a: figure out what kind of derived type declaration we have.
4556 if Private_Extension
then
4558 Set_Ekind
(Derived_Type
, E_Record_Type_With_Private
);
4561 Type_Def
:= Type_Definition
(N
);
4563 -- Ekind (Parent_Base) in not necessarily E_Record_Type since
4564 -- Parent_Base can be a private type or private extension. However,
4565 -- for tagged types with an extension the newly added fields are
4566 -- visible and hence the Derived_Type is always an E_Record_Type.
4567 -- (except that the parent may have its own private fields).
4568 -- For untagged types we preserve the Ekind of the Parent_Base.
4570 if Present
(Record_Extension_Part
(Type_Def
)) then
4571 Set_Ekind
(Derived_Type
, E_Record_Type
);
4573 Set_Ekind
(Derived_Type
, Ekind
(Parent_Base
));
4577 -- Indic can either be an N_Identifier if the subtype indication
4578 -- contains no constraint or an N_Subtype_Indication if the subtype
4579 -- indication has a constraint.
4581 Indic
:= Subtype_Indication
(Type_Def
);
4582 Constraint_Present
:= (Nkind
(Indic
) = N_Subtype_Indication
);
4584 if Constraint_Present
then
4585 if not Has_Discriminants
(Parent_Base
) then
4587 ("invalid constraint: type has no discriminant",
4588 Constraint
(Indic
));
4590 Constraint_Present
:= False;
4591 Rewrite
(Indic
, New_Copy_Tree
(Subtype_Mark
(Indic
)));
4593 elsif Is_Constrained
(Parent_Type
) then
4595 ("invalid constraint: parent type is already constrained",
4596 Constraint
(Indic
));
4598 Constraint_Present
:= False;
4599 Rewrite
(Indic
, New_Copy_Tree
(Subtype_Mark
(Indic
)));
4603 -- STEP 0b: If needed, apply transformation given in point 5. above.
4605 if not Private_Extension
4606 and then Has_Discriminants
(Parent_Type
)
4607 and then not Discriminant_Specs
4608 and then (Is_Constrained
(Parent_Type
) or else Constraint_Present
)
4610 -- First, we must analyze the constraint (see comment in point 5.).
4612 if Constraint_Present
then
4613 New_Discrs
:= Build_Discriminant_Constraints
(Parent_Type
, Indic
);
4615 if Has_Discriminants
(Derived_Type
)
4616 and then Has_Private_Declaration
(Derived_Type
)
4617 and then Present
(Discriminant_Constraint
(Derived_Type
))
4619 -- Verify that constraints of the full view conform to those
4620 -- given in partial view.
4626 C1
:= First_Elmt
(New_Discrs
);
4627 C2
:= First_Elmt
(Discriminant_Constraint
(Derived_Type
));
4629 while Present
(C1
) and then Present
(C2
) loop
4631 Fully_Conformant_Expressions
(Node
(C1
), Node
(C2
))
4634 "constraint not conformant to previous declaration",
4644 -- Insert and analyze the declaration for the unconstrained base type
4646 New_Base
:= Create_Itype
(Ekind
(Derived_Type
), N
, Derived_Type
, 'B');
4649 Make_Full_Type_Declaration
(Loc
,
4650 Defining_Identifier
=> New_Base
,
4652 Make_Derived_Type_Definition
(Loc
,
4653 Abstract_Present
=> Abstract_Present
(Type_Def
),
4654 Subtype_Indication
=>
4655 New_Occurrence_Of
(Parent_Base
, Loc
),
4656 Record_Extension_Part
=>
4657 Relocate_Node
(Record_Extension_Part
(Type_Def
))));
4659 Set_Parent
(New_Decl
, Parent
(N
));
4660 Mark_Rewrite_Insertion
(New_Decl
);
4661 Insert_Before
(N
, New_Decl
);
4663 -- Note that this call passes False for the Derive_Subps
4664 -- parameter because subprogram derivation is deferred until
4665 -- after creating the subtype (see below).
4668 (New_Decl
, Parent_Base
, New_Base
,
4669 Is_Completion
=> True, Derive_Subps
=> False);
4671 -- ??? This needs re-examination to determine whether the
4672 -- above call can simply be replaced by a call to Analyze.
4674 Set_Analyzed
(New_Decl
);
4676 -- Insert and analyze the declaration for the constrained subtype
4678 if Constraint_Present
then
4680 Make_Subtype_Indication
(Loc
,
4681 Subtype_Mark
=> New_Occurrence_Of
(New_Base
, Loc
),
4682 Constraint
=> Relocate_Node
(Constraint
(Indic
)));
4686 Constr_List
: constant List_Id
:= New_List
;
4691 C
:= First_Elmt
(Discriminant_Constraint
(Parent_Type
));
4692 while Present
(C
) loop
4695 -- It is safe here to call New_Copy_Tree since
4696 -- Force_Evaluation was called on each constraint in
4697 -- Build_Discriminant_Constraints.
4699 Append
(New_Copy_Tree
(Expr
), To
=> Constr_List
);
4705 Make_Subtype_Indication
(Loc
,
4706 Subtype_Mark
=> New_Occurrence_Of
(New_Base
, Loc
),
4708 Make_Index_Or_Discriminant_Constraint
(Loc
, Constr_List
));
4713 Make_Subtype_Declaration
(Loc
,
4714 Defining_Identifier
=> Derived_Type
,
4715 Subtype_Indication
=> New_Indic
));
4719 -- Derivation of subprograms must be delayed until the
4720 -- full subtype has been established to ensure proper
4721 -- overriding of subprograms inherited by full types.
4722 -- If the derivations occurred as part of the call to
4723 -- Build_Derived_Type above, then the check for type
4724 -- conformance would fail because earlier primitive
4725 -- subprograms could still refer to the full type prior
4726 -- the change to the new subtype and hence wouldn't
4727 -- match the new base type created here.
4729 Derive_Subprograms
(Parent_Type
, Derived_Type
);
4731 -- For tagged types the Discriminant_Constraint of the new base itype
4732 -- is inherited from the first subtype so that no subtype conformance
4733 -- problem arise when the first subtype overrides primitive
4734 -- operations inherited by the implicit base type.
4737 Set_Discriminant_Constraint
4738 (New_Base
, Discriminant_Constraint
(Derived_Type
));
4744 -- If we get here Derived_Type will have no discriminants or it will be
4745 -- a discriminated unconstrained base type.
4747 -- STEP 1a: perform preliminary actions/checks for derived tagged types
4750 -- The parent type is frozen for non-private extensions (RM 13.14(7))
4752 if not Private_Extension
then
4753 Freeze_Before
(N
, Parent_Type
);
4756 if Type_Access_Level
(Derived_Type
) /= Type_Access_Level
(Parent_Type
)
4757 and then not Is_Generic_Type
(Derived_Type
)
4759 if Is_Controlled
(Parent_Type
) then
4761 ("controlled type must be declared at the library level",
4765 ("type extension at deeper accessibility level than parent",
4771 GB
: constant Node_Id
:= Enclosing_Generic_Body
(Derived_Type
);
4775 and then GB
/= Enclosing_Generic_Body
(Parent_Base
)
4778 ("parent type of& must not be outside generic body"
4779 & " ('R'M 3.9.1(4))",
4780 Indic
, Derived_Type
);
4786 -- STEP 1b : preliminary cleanup of the full view of private types
4788 -- If the type is already marked as having discriminants, then it's the
4789 -- completion of a private type or private extension and we need to
4790 -- retain the discriminants from the partial view if the current
4791 -- declaration has Discriminant_Specifications so that we can verify
4792 -- conformance. However, we must remove any existing components that
4793 -- were inherited from the parent (and attached in Copy_And_Swap)
4794 -- because the full type inherits all appropriate components anyway, and
4795 -- we don't want the partial view's components interfering.
4797 if Has_Discriminants
(Derived_Type
) and then Discriminant_Specs
then
4798 Discrim
:= First_Discriminant
(Derived_Type
);
4800 Last_Discrim
:= Discrim
;
4801 Next_Discriminant
(Discrim
);
4802 exit when No
(Discrim
);
4805 Set_Last_Entity
(Derived_Type
, Last_Discrim
);
4807 -- In all other cases wipe out the list of inherited components (even
4808 -- inherited discriminants), it will be properly rebuilt here.
4811 Set_First_Entity
(Derived_Type
, Empty
);
4812 Set_Last_Entity
(Derived_Type
, Empty
);
4815 -- STEP 1c: Initialize some flags for the Derived_Type
4817 -- The following flags must be initialized here so that
4818 -- Process_Discriminants can check that discriminants of tagged types
4819 -- do not have a default initial value and that access discriminants
4820 -- are only specified for limited records. For completeness, these
4821 -- flags are also initialized along with all the other flags below.
4823 Set_Is_Tagged_Type
(Derived_Type
, Is_Tagged
);
4824 Set_Is_Limited_Record
(Derived_Type
, Is_Limited_Record
(Parent_Type
));
4826 -- STEP 2a: process discriminants of derived type if any.
4828 New_Scope
(Derived_Type
);
4830 if Discriminant_Specs
then
4831 Set_Has_Unknown_Discriminants
(Derived_Type
, False);
4833 -- The following call initializes fields Has_Discriminants and
4834 -- Discriminant_Constraint, unless we are processing the completion
4835 -- of a private type declaration.
4837 Check_Or_Process_Discriminants
(N
, Derived_Type
);
4839 -- For non-tagged types the constraint on the Parent_Type must be
4840 -- present and is used to rename the discriminants.
4842 if not Is_Tagged
and then not Has_Discriminants
(Parent_Type
) then
4843 Error_Msg_N
("untagged parent must have discriminants", Indic
);
4845 elsif not Is_Tagged
and then not Constraint_Present
then
4847 ("discriminant constraint needed for derived untagged records",
4850 -- Otherwise the parent subtype must be constrained unless we have a
4851 -- private extension.
4853 elsif not Constraint_Present
4854 and then not Private_Extension
4855 and then not Is_Constrained
(Parent_Type
)
4858 ("unconstrained type not allowed in this context", Indic
);
4860 elsif Constraint_Present
then
4861 -- The following call sets the field Corresponding_Discriminant
4862 -- for the discriminants in the Derived_Type.
4864 Discs
:= Build_Discriminant_Constraints
(Parent_Type
, Indic
, True);
4866 -- For untagged types all new discriminants must rename
4867 -- discriminants in the parent. For private extensions new
4868 -- discriminants cannot rename old ones (implied by [7.3(13)]).
4870 Discrim
:= First_Discriminant
(Derived_Type
);
4872 while Present
(Discrim
) loop
4874 and then not Present
(Corresponding_Discriminant
(Discrim
))
4877 ("new discriminants must constrain old ones", Discrim
);
4879 elsif Private_Extension
4880 and then Present
(Corresponding_Discriminant
(Discrim
))
4883 ("only static constraints allowed for parent"
4884 & " discriminants in the partial view", Indic
);
4888 -- If a new discriminant is used in the constraint,
4889 -- then its subtype must be statically compatible
4890 -- with the parent discriminant's subtype (3.7(15)).
4892 if Present
(Corresponding_Discriminant
(Discrim
))
4894 not Subtypes_Statically_Compatible
4896 Etype
(Corresponding_Discriminant
(Discrim
)))
4899 ("subtype must be compatible with parent discriminant",
4903 Next_Discriminant
(Discrim
);
4907 -- STEP 2b: No new discriminants, inherit discriminants if any
4910 if Private_Extension
then
4911 Set_Has_Unknown_Discriminants
4912 (Derived_Type
, Has_Unknown_Discriminants
(Parent_Type
)
4913 or else Unknown_Discriminants_Present
(N
));
4915 Set_Has_Unknown_Discriminants
4916 (Derived_Type
, Has_Unknown_Discriminants
(Parent_Type
));
4919 if not Has_Unknown_Discriminants
(Derived_Type
)
4920 and then Has_Discriminants
(Parent_Type
)
4922 Inherit_Discrims
:= True;
4923 Set_Has_Discriminants
4924 (Derived_Type
, True);
4925 Set_Discriminant_Constraint
4926 (Derived_Type
, Discriminant_Constraint
(Parent_Base
));
4929 -- The following test is true for private types (remember
4930 -- transformation 5. is not applied to those) and in an error
4933 if Constraint_Present
then
4934 Discs
:= Build_Discriminant_Constraints
(Parent_Type
, Indic
);
4937 -- For now mark a new derived type as constrained only if it has no
4938 -- discriminants. At the end of Build_Derived_Record_Type we properly
4939 -- set this flag in the case of private extensions. See comments in
4940 -- point 9. just before body of Build_Derived_Record_Type.
4944 not (Inherit_Discrims
4945 or else Has_Unknown_Discriminants
(Derived_Type
)));
4948 -- STEP 3: initialize fields of derived type.
4950 Set_Is_Tagged_Type
(Derived_Type
, Is_Tagged
);
4951 Set_Stored_Constraint
(Derived_Type
, No_Elist
);
4953 -- Fields inherited from the Parent_Type
4956 (Derived_Type
, Einfo
.Discard_Names
(Parent_Type
));
4957 Set_Has_Specified_Layout
4958 (Derived_Type
, Has_Specified_Layout
(Parent_Type
));
4959 Set_Is_Limited_Composite
4960 (Derived_Type
, Is_Limited_Composite
(Parent_Type
));
4961 Set_Is_Limited_Record
4962 (Derived_Type
, Is_Limited_Record
(Parent_Type
));
4963 Set_Is_Private_Composite
4964 (Derived_Type
, Is_Private_Composite
(Parent_Type
));
4966 -- Fields inherited from the Parent_Base
4968 Set_Has_Controlled_Component
4969 (Derived_Type
, Has_Controlled_Component
(Parent_Base
));
4970 Set_Has_Non_Standard_Rep
4971 (Derived_Type
, Has_Non_Standard_Rep
(Parent_Base
));
4972 Set_Has_Primitive_Operations
4973 (Derived_Type
, Has_Primitive_Operations
(Parent_Base
));
4975 -- Direct controlled types do not inherit Finalize_Storage_Only flag
4977 if not Is_Controlled
(Parent_Type
) then
4978 Set_Finalize_Storage_Only
4979 (Derived_Type
, Finalize_Storage_Only
(Parent_Type
));
4982 -- Set fields for private derived types.
4984 if Is_Private_Type
(Derived_Type
) then
4985 Set_Depends_On_Private
(Derived_Type
, True);
4986 Set_Private_Dependents
(Derived_Type
, New_Elmt_List
);
4988 -- Inherit fields from non private record types. If this is the
4989 -- completion of a derivation from a private type, the parent itself
4990 -- is private, and the attributes come from its full view, which must
4994 if Is_Private_Type
(Parent_Base
)
4995 and then not Is_Record_Type
(Parent_Base
)
4997 Set_Component_Alignment
4998 (Derived_Type
, Component_Alignment
(Full_View
(Parent_Base
)));
5000 (Derived_Type
, C_Pass_By_Copy
(Full_View
(Parent_Base
)));
5002 Set_Component_Alignment
5003 (Derived_Type
, Component_Alignment
(Parent_Base
));
5006 (Derived_Type
, C_Pass_By_Copy
(Parent_Base
));
5010 -- Set fields for tagged types
5013 Set_Primitive_Operations
(Derived_Type
, New_Elmt_List
);
5015 -- All tagged types defined in Ada.Finalization are controlled
5017 if Chars
(Scope
(Derived_Type
)) = Name_Finalization
5018 and then Chars
(Scope
(Scope
(Derived_Type
))) = Name_Ada
5019 and then Scope
(Scope
(Scope
(Derived_Type
))) = Standard_Standard
5021 Set_Is_Controlled
(Derived_Type
);
5023 Set_Is_Controlled
(Derived_Type
, Is_Controlled
(Parent_Base
));
5026 Make_Class_Wide_Type
(Derived_Type
);
5027 Set_Is_Abstract
(Derived_Type
, Abstract_Present
(Type_Def
));
5029 if Has_Discriminants
(Derived_Type
)
5030 and then Constraint_Present
5032 Set_Stored_Constraint
5033 (Derived_Type
, Expand_To_Stored_Constraint
(Parent_Base
, Discs
));
5037 Set_Is_Packed
(Derived_Type
, Is_Packed
(Parent_Base
));
5038 Set_Has_Non_Standard_Rep
5039 (Derived_Type
, Has_Non_Standard_Rep
(Parent_Base
));
5042 -- STEP 4: Inherit components from the parent base and constrain them.
5043 -- Apply the second transformation described in point 6. above.
5045 if (not Is_Empty_Elmt_List
(Discs
) or else Inherit_Discrims
)
5046 or else not Has_Discriminants
(Parent_Type
)
5047 or else not Is_Constrained
(Parent_Type
)
5051 Constrs
:= Discriminant_Constraint
(Parent_Type
);
5054 Assoc_List
:= Inherit_Components
(N
,
5055 Parent_Base
, Derived_Type
, Is_Tagged
, Inherit_Discrims
, Constrs
);
5057 -- STEP 5a: Copy the parent record declaration for untagged types
5059 if not Is_Tagged
then
5061 -- Discriminant_Constraint (Derived_Type) has been properly
5062 -- constructed. Save it and temporarily set it to Empty because we do
5063 -- not want the call to New_Copy_Tree below to mess this list.
5065 if Has_Discriminants
(Derived_Type
) then
5066 Save_Discr_Constr
:= Discriminant_Constraint
(Derived_Type
);
5067 Set_Discriminant_Constraint
(Derived_Type
, No_Elist
);
5069 Save_Discr_Constr
:= No_Elist
;
5072 -- Save the Etype field of Derived_Type. It is correctly set now, but
5073 -- the call to New_Copy tree may remap it to point to itself, which
5074 -- is not what we want. Ditto for the Next_Entity field.
5076 Save_Etype
:= Etype
(Derived_Type
);
5077 Save_Next_Entity
:= Next_Entity
(Derived_Type
);
5079 -- Assoc_List maps all stored discriminants in the Parent_Base to
5080 -- stored discriminants in the Derived_Type. It is fundamental that
5081 -- no types or itypes with discriminants other than the stored
5082 -- discriminants appear in the entities declared inside
5083 -- Derived_Type. Gigi won't like it.
5087 (Parent
(Parent_Base
), Map
=> Assoc_List
, New_Sloc
=> Loc
);
5089 -- Restore the fields saved prior to the New_Copy_Tree call
5090 -- and compute the stored constraint.
5092 Set_Etype
(Derived_Type
, Save_Etype
);
5093 Set_Next_Entity
(Derived_Type
, Save_Next_Entity
);
5095 if Has_Discriminants
(Derived_Type
) then
5096 Set_Discriminant_Constraint
5097 (Derived_Type
, Save_Discr_Constr
);
5098 Set_Stored_Constraint
5099 (Derived_Type
, Expand_To_Stored_Constraint
(Parent_Base
, Discs
));
5100 Replace_Components
(Derived_Type
, New_Decl
);
5103 -- Insert the new derived type declaration
5105 Rewrite
(N
, New_Decl
);
5107 -- STEP 5b: Complete the processing for record extensions in generics
5109 -- There is no completion for record extensions declared in the
5110 -- parameter part of a generic, so we need to complete processing for
5111 -- these generic record extensions here. The Record_Type_Definition call
5112 -- will change the Ekind of the components from E_Void to E_Component.
5114 elsif Private_Extension
and then Is_Generic_Type
(Derived_Type
) then
5115 Record_Type_Definition
(Empty
, Derived_Type
);
5117 -- STEP 5c: Process the record extension for non private tagged types.
5119 elsif not Private_Extension
then
5120 -- Add the _parent field in the derived type.
5122 Expand_Derived_Record
(Derived_Type
, Type_Def
);
5124 -- Analyze the record extension
5126 Record_Type_Definition
5127 (Record_Extension_Part
(Type_Def
), Derived_Type
);
5132 if Etype
(Derived_Type
) = Any_Type
then
5136 -- Set delayed freeze and then derive subprograms, we need to do
5137 -- this in this order so that derived subprograms inherit the
5138 -- derived freeze if necessary.
5140 Set_Has_Delayed_Freeze
(Derived_Type
);
5141 if Derive_Subps
then
5142 Derive_Subprograms
(Parent_Type
, Derived_Type
);
5145 -- If we have a private extension which defines a constrained derived
5146 -- type mark as constrained here after we have derived subprograms. See
5147 -- comment on point 9. just above the body of Build_Derived_Record_Type.
5149 if Private_Extension
and then Inherit_Discrims
then
5150 if Constraint_Present
and then not Is_Empty_Elmt_List
(Discs
) then
5151 Set_Is_Constrained
(Derived_Type
, True);
5152 Set_Discriminant_Constraint
(Derived_Type
, Discs
);
5154 elsif Is_Constrained
(Parent_Type
) then
5156 (Derived_Type
, True);
5157 Set_Discriminant_Constraint
5158 (Derived_Type
, Discriminant_Constraint
(Parent_Type
));
5162 end Build_Derived_Record_Type
;
5164 ------------------------
5165 -- Build_Derived_Type --
5166 ------------------------
5168 procedure Build_Derived_Type
5170 Parent_Type
: Entity_Id
;
5171 Derived_Type
: Entity_Id
;
5172 Is_Completion
: Boolean;
5173 Derive_Subps
: Boolean := True)
5175 Parent_Base
: constant Entity_Id
:= Base_Type
(Parent_Type
);
5178 -- Set common attributes
5180 Set_Scope
(Derived_Type
, Current_Scope
);
5182 Set_Ekind
(Derived_Type
, Ekind
(Parent_Base
));
5183 Set_Etype
(Derived_Type
, Parent_Base
);
5184 Set_Has_Task
(Derived_Type
, Has_Task
(Parent_Base
));
5186 Set_Size_Info
(Derived_Type
, Parent_Type
);
5187 Set_RM_Size
(Derived_Type
, RM_Size
(Parent_Type
));
5188 Set_Convention
(Derived_Type
, Convention
(Parent_Type
));
5189 Set_Is_Controlled
(Derived_Type
, Is_Controlled
(Parent_Type
));
5191 -- The derived type inherits the representation clauses of the parent.
5192 -- However, for a private type that is completed by a derivation, there
5193 -- may be operation attributes that have been specified already (stream
5194 -- attributes and External_Tag) and those must be provided. Finally,
5195 -- if the partial view is a private extension, the representation items
5196 -- of the parent have been inherited already, and should not be chained
5197 -- twice to the derived type.
5199 if Is_Tagged_Type
(Parent_Type
)
5200 and then Present
(First_Rep_Item
(Derived_Type
))
5202 -- The existing items are either operational items or items inherited
5203 -- from a private extension declaration.
5206 Rep
: Node_Id
:= First_Rep_Item
(Derived_Type
);
5207 Found
: Boolean := False;
5210 while Present
(Rep
) loop
5211 if Rep
= First_Rep_Item
(Parent_Type
) then
5215 Rep
:= Next_Rep_Item
(Rep
);
5221 (First_Rep_Item
(Derived_Type
), First_Rep_Item
(Parent_Type
));
5226 Set_First_Rep_Item
(Derived_Type
, First_Rep_Item
(Parent_Type
));
5229 case Ekind
(Parent_Type
) is
5230 when Numeric_Kind
=>
5231 Build_Derived_Numeric_Type
(N
, Parent_Type
, Derived_Type
);
5234 Build_Derived_Array_Type
(N
, Parent_Type
, Derived_Type
);
5238 | Class_Wide_Kind
=>
5239 Build_Derived_Record_Type
5240 (N
, Parent_Type
, Derived_Type
, Derive_Subps
);
5243 when Enumeration_Kind
=>
5244 Build_Derived_Enumeration_Type
(N
, Parent_Type
, Derived_Type
);
5247 Build_Derived_Access_Type
(N
, Parent_Type
, Derived_Type
);
5249 when Incomplete_Or_Private_Kind
=>
5250 Build_Derived_Private_Type
5251 (N
, Parent_Type
, Derived_Type
, Is_Completion
, Derive_Subps
);
5253 -- For discriminated types, the derivation includes deriving
5254 -- primitive operations. For others it is done below.
5256 if Is_Tagged_Type
(Parent_Type
)
5257 or else Has_Discriminants
(Parent_Type
)
5258 or else (Present
(Full_View
(Parent_Type
))
5259 and then Has_Discriminants
(Full_View
(Parent_Type
)))
5264 when Concurrent_Kind
=>
5265 Build_Derived_Concurrent_Type
(N
, Parent_Type
, Derived_Type
);
5268 raise Program_Error
;
5271 if Etype
(Derived_Type
) = Any_Type
then
5275 -- Set delayed freeze and then derive subprograms, we need to do
5276 -- this in this order so that derived subprograms inherit the
5277 -- derived freeze if necessary.
5279 Set_Has_Delayed_Freeze
(Derived_Type
);
5280 if Derive_Subps
then
5281 Derive_Subprograms
(Parent_Type
, Derived_Type
);
5284 Set_Has_Primitive_Operations
5285 (Base_Type
(Derived_Type
), Has_Primitive_Operations
(Parent_Type
));
5286 end Build_Derived_Type
;
5288 -----------------------
5289 -- Build_Discriminal --
5290 -----------------------
5292 procedure Build_Discriminal
(Discrim
: Entity_Id
) is
5293 D_Minal
: Entity_Id
;
5294 CR_Disc
: Entity_Id
;
5297 -- A discriminal has the same names as the discriminant.
5299 D_Minal
:= Make_Defining_Identifier
(Sloc
(Discrim
), Chars
(Discrim
));
5301 Set_Ekind
(D_Minal
, E_In_Parameter
);
5302 Set_Mechanism
(D_Minal
, Default_Mechanism
);
5303 Set_Etype
(D_Minal
, Etype
(Discrim
));
5305 Set_Discriminal
(Discrim
, D_Minal
);
5306 Set_Discriminal_Link
(D_Minal
, Discrim
);
5308 -- For task types, build at once the discriminants of the corresponding
5309 -- record, which are needed if discriminants are used in entry defaults
5310 -- and in family bounds.
5312 if Is_Concurrent_Type
(Current_Scope
)
5313 or else Is_Limited_Type
(Current_Scope
)
5315 CR_Disc
:= Make_Defining_Identifier
(Sloc
(Discrim
), Chars
(Discrim
));
5317 Set_Ekind
(CR_Disc
, E_In_Parameter
);
5318 Set_Mechanism
(CR_Disc
, Default_Mechanism
);
5319 Set_Etype
(CR_Disc
, Etype
(Discrim
));
5320 Set_CR_Discriminant
(Discrim
, CR_Disc
);
5322 end Build_Discriminal
;
5324 ------------------------------------
5325 -- Build_Discriminant_Constraints --
5326 ------------------------------------
5328 function Build_Discriminant_Constraints
5331 Derived_Def
: Boolean := False) return Elist_Id
5333 C
: constant Node_Id
:= Constraint
(Def
);
5334 Nb_Discr
: constant Nat
:= Number_Discriminants
(T
);
5335 Discr_Expr
: array (1 .. Nb_Discr
) of Node_Id
:= (others => Empty
);
5336 -- Saves the expression corresponding to a given discriminant in T.
5338 function Pos_Of_Discr
(T
: Entity_Id
; D
: Entity_Id
) return Nat
;
5339 -- Return the Position number within array Discr_Expr of a discriminant
5340 -- D within the discriminant list of the discriminated type T.
5346 function Pos_Of_Discr
(T
: Entity_Id
; D
: Entity_Id
) return Nat
is
5350 Disc
:= First_Discriminant
(T
);
5351 for J
in Discr_Expr
'Range loop
5356 Next_Discriminant
(Disc
);
5359 -- Note: Since this function is called on discriminants that are
5360 -- known to belong to the discriminated type, falling through the
5361 -- loop with no match signals an internal compiler error.
5363 raise Program_Error
;
5366 -- Declarations local to Build_Discriminant_Constraints
5370 Elist
: constant Elist_Id
:= New_Elmt_List
;
5378 Discrim_Present
: Boolean := False;
5380 -- Start of processing for Build_Discriminant_Constraints
5383 -- The following loop will process positional associations only.
5384 -- For a positional association, the (single) discriminant is
5385 -- implicitly specified by position, in textual order (RM 3.7.2).
5387 Discr
:= First_Discriminant
(T
);
5388 Constr
:= First
(Constraints
(C
));
5390 for D
in Discr_Expr
'Range loop
5391 exit when Nkind
(Constr
) = N_Discriminant_Association
;
5394 Error_Msg_N
("too few discriminants given in constraint", C
);
5395 return New_Elmt_List
;
5397 elsif Nkind
(Constr
) = N_Range
5398 or else (Nkind
(Constr
) = N_Attribute_Reference
5400 Attribute_Name
(Constr
) = Name_Range
)
5403 ("a range is not a valid discriminant constraint", Constr
);
5404 Discr_Expr
(D
) := Error
;
5407 Analyze_And_Resolve
(Constr
, Base_Type
(Etype
(Discr
)));
5408 Discr_Expr
(D
) := Constr
;
5411 Next_Discriminant
(Discr
);
5415 if No
(Discr
) and then Present
(Constr
) then
5416 Error_Msg_N
("too many discriminants given in constraint", Constr
);
5417 return New_Elmt_List
;
5420 -- Named associations can be given in any order, but if both positional
5421 -- and named associations are used in the same discriminant constraint,
5422 -- then positional associations must occur first, at their normal
5423 -- position. Hence once a named association is used, the rest of the
5424 -- discriminant constraint must use only named associations.
5426 while Present
(Constr
) loop
5428 -- Positional association forbidden after a named association.
5430 if Nkind
(Constr
) /= N_Discriminant_Association
then
5431 Error_Msg_N
("positional association follows named one", Constr
);
5432 return New_Elmt_List
;
5434 -- Otherwise it is a named association
5437 -- E records the type of the discriminants in the named
5438 -- association. All the discriminants specified in the same name
5439 -- association must have the same type.
5443 -- Search the list of discriminants in T to see if the simple name
5444 -- given in the constraint matches any of them.
5446 Id
:= First
(Selector_Names
(Constr
));
5447 while Present
(Id
) loop
5450 -- If Original_Discriminant is present, we are processing a
5451 -- generic instantiation and this is an instance node. We need
5452 -- to find the name of the corresponding discriminant in the
5453 -- actual record type T and not the name of the discriminant in
5454 -- the generic formal. Example:
5457 -- type G (D : int) is private;
5459 -- subtype W is G (D => 1);
5461 -- type Rec (X : int) is record ... end record;
5462 -- package Q is new P (G => Rec);
5464 -- At the point of the instantiation, formal type G is Rec
5465 -- and therefore when reanalyzing "subtype W is G (D => 1);"
5466 -- which really looks like "subtype W is Rec (D => 1);" at
5467 -- the point of instantiation, we want to find the discriminant
5468 -- that corresponds to D in Rec, ie X.
5470 if Present
(Original_Discriminant
(Id
)) then
5471 Discr
:= Find_Corresponding_Discriminant
(Id
, T
);
5475 Discr
:= First_Discriminant
(T
);
5476 while Present
(Discr
) loop
5477 if Chars
(Discr
) = Chars
(Id
) then
5482 Next_Discriminant
(Discr
);
5486 Error_Msg_N
("& does not match any discriminant", Id
);
5487 return New_Elmt_List
;
5489 -- The following is only useful for the benefit of generic
5490 -- instances but it does not interfere with other
5491 -- processing for the non-generic case so we do it in all
5492 -- cases (for generics this statement is executed when
5493 -- processing the generic definition, see comment at the
5494 -- beginning of this if statement).
5497 Set_Original_Discriminant
(Id
, Discr
);
5501 Position
:= Pos_Of_Discr
(T
, Discr
);
5503 if Present
(Discr_Expr
(Position
)) then
5504 Error_Msg_N
("duplicate constraint for discriminant&", Id
);
5507 -- Each discriminant specified in the same named association
5508 -- must be associated with a separate copy of the
5509 -- corresponding expression.
5511 if Present
(Next
(Id
)) then
5512 Expr
:= New_Copy_Tree
(Expression
(Constr
));
5513 Set_Parent
(Expr
, Parent
(Expression
(Constr
)));
5515 Expr
:= Expression
(Constr
);
5518 Discr_Expr
(Position
) := Expr
;
5519 Analyze_And_Resolve
(Expr
, Base_Type
(Etype
(Discr
)));
5522 -- A discriminant association with more than one discriminant
5523 -- name is only allowed if the named discriminants are all of
5524 -- the same type (RM 3.7.1(8)).
5527 E
:= Base_Type
(Etype
(Discr
));
5529 elsif Base_Type
(Etype
(Discr
)) /= E
then
5531 ("all discriminants in an association " &
5532 "must have the same type", Id
);
5542 -- A discriminant constraint must provide exactly one value for each
5543 -- discriminant of the type (RM 3.7.1(8)).
5545 for J
in Discr_Expr
'Range loop
5546 if No
(Discr_Expr
(J
)) then
5547 Error_Msg_N
("too few discriminants given in constraint", C
);
5548 return New_Elmt_List
;
5552 -- Determine if there are discriminant expressions in the constraint.
5554 for J
in Discr_Expr
'Range loop
5555 if Denotes_Discriminant
(Discr_Expr
(J
), Check_Protected
=> True) then
5556 Discrim_Present
:= True;
5560 -- Build an element list consisting of the expressions given in the
5561 -- discriminant constraint and apply the appropriate range
5562 -- checks. The list is constructed after resolving any named
5563 -- discriminant associations and therefore the expressions appear in
5564 -- the textual order of the discriminants.
5566 Discr
:= First_Discriminant
(T
);
5567 for J
in Discr_Expr
'Range loop
5568 if Discr_Expr
(J
) /= Error
then
5570 Append_Elmt
(Discr_Expr
(J
), Elist
);
5572 -- If any of the discriminant constraints is given by a
5573 -- discriminant and we are in a derived type declaration we
5574 -- have a discriminant renaming. Establish link between new
5575 -- and old discriminant.
5577 if Denotes_Discriminant
(Discr_Expr
(J
)) then
5579 Set_Corresponding_Discriminant
5580 (Entity
(Discr_Expr
(J
)), Discr
);
5583 -- Force the evaluation of non-discriminant expressions.
5584 -- If we have found a discriminant in the constraint 3.4(26)
5585 -- and 3.8(18) demand that no range checks are performed are
5586 -- after evaluation. If the constraint is for a component
5587 -- definition that has a per-object constraint, expressions are
5588 -- evaluated but not checked either. In all other cases perform
5592 if Discrim_Present
then
5595 elsif Nkind
(Parent
(Def
)) = N_Component_Declaration
5597 Has_Per_Object_Constraint
5598 (Defining_Identifier
(Parent
(Def
)))
5603 Apply_Range_Check
(Discr_Expr
(J
), Etype
(Discr
));
5606 Force_Evaluation
(Discr_Expr
(J
));
5609 -- Check that the designated type of an access discriminant's
5610 -- expression is not a class-wide type unless the discriminant's
5611 -- designated type is also class-wide.
5613 if Ekind
(Etype
(Discr
)) = E_Anonymous_Access_Type
5614 and then not Is_Class_Wide_Type
5615 (Designated_Type
(Etype
(Discr
)))
5616 and then Etype
(Discr_Expr
(J
)) /= Any_Type
5617 and then Is_Class_Wide_Type
5618 (Designated_Type
(Etype
(Discr_Expr
(J
))))
5620 Wrong_Type
(Discr_Expr
(J
), Etype
(Discr
));
5624 Next_Discriminant
(Discr
);
5628 end Build_Discriminant_Constraints
;
5630 ---------------------------------
5631 -- Build_Discriminated_Subtype --
5632 ---------------------------------
5634 procedure Build_Discriminated_Subtype
5638 Related_Nod
: Node_Id
;
5639 For_Access
: Boolean := False)
5641 Has_Discrs
: constant Boolean := Has_Discriminants
(T
);
5642 Constrained
: constant Boolean
5644 and then not Is_Empty_Elmt_List
(Elist
)
5645 and then not Is_Class_Wide_Type
(T
))
5646 or else Is_Constrained
(T
);
5649 if Ekind
(T
) = E_Record_Type
then
5651 Set_Ekind
(Def_Id
, E_Private_Subtype
);
5652 Set_Is_For_Access_Subtype
(Def_Id
, True);
5654 Set_Ekind
(Def_Id
, E_Record_Subtype
);
5657 elsif Ekind
(T
) = E_Task_Type
then
5658 Set_Ekind
(Def_Id
, E_Task_Subtype
);
5660 elsif Ekind
(T
) = E_Protected_Type
then
5661 Set_Ekind
(Def_Id
, E_Protected_Subtype
);
5663 elsif Is_Private_Type
(T
) then
5664 Set_Ekind
(Def_Id
, Subtype_Kind
(Ekind
(T
)));
5666 elsif Is_Class_Wide_Type
(T
) then
5667 Set_Ekind
(Def_Id
, E_Class_Wide_Subtype
);
5670 -- Incomplete type. Attach subtype to list of dependents, to be
5671 -- completed with full view of parent type.
5673 Set_Ekind
(Def_Id
, Ekind
(T
));
5674 Append_Elmt
(Def_Id
, Private_Dependents
(T
));
5677 Set_Etype
(Def_Id
, T
);
5678 Init_Size_Align
(Def_Id
);
5679 Set_Has_Discriminants
(Def_Id
, Has_Discrs
);
5680 Set_Is_Constrained
(Def_Id
, Constrained
);
5682 Set_First_Entity
(Def_Id
, First_Entity
(T
));
5683 Set_Last_Entity
(Def_Id
, Last_Entity
(T
));
5684 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
5686 if Is_Tagged_Type
(T
) then
5687 Set_Is_Tagged_Type
(Def_Id
);
5688 Make_Class_Wide_Type
(Def_Id
);
5691 Set_Stored_Constraint
(Def_Id
, No_Elist
);
5694 Set_Discriminant_Constraint
(Def_Id
, Elist
);
5695 Set_Stored_Constraint_From_Discriminant_Constraint
(Def_Id
);
5698 if Is_Tagged_Type
(T
) then
5699 Set_Primitive_Operations
(Def_Id
, Primitive_Operations
(T
));
5700 Set_Is_Abstract
(Def_Id
, Is_Abstract
(T
));
5703 -- Subtypes introduced by component declarations do not need to be
5704 -- marked as delayed, and do not get freeze nodes, because the semantics
5705 -- verifies that the parents of the subtypes are frozen before the
5706 -- enclosing record is frozen.
5708 if not Is_Type
(Scope
(Def_Id
)) then
5709 Set_Depends_On_Private
(Def_Id
, Depends_On_Private
(T
));
5711 if Is_Private_Type
(T
)
5712 and then Present
(Full_View
(T
))
5714 Conditional_Delay
(Def_Id
, Full_View
(T
));
5716 Conditional_Delay
(Def_Id
, T
);
5720 if Is_Record_Type
(T
) then
5721 Set_Is_Limited_Record
(Def_Id
, Is_Limited_Record
(T
));
5724 and then not Is_Empty_Elmt_List
(Elist
)
5725 and then not For_Access
5727 Create_Constrained_Components
(Def_Id
, Related_Nod
, T
, Elist
);
5728 elsif not For_Access
then
5729 Set_Cloned_Subtype
(Def_Id
, T
);
5733 end Build_Discriminated_Subtype
;
5735 ------------------------
5736 -- Build_Scalar_Bound --
5737 ------------------------
5739 function Build_Scalar_Bound
5742 Der_T
: Entity_Id
) return Node_Id
5744 New_Bound
: Entity_Id
;
5747 -- Note: not clear why this is needed, how can the original bound
5748 -- be unanalyzed at this point? and if it is, what business do we
5749 -- have messing around with it? and why is the base type of the
5750 -- parent type the right type for the resolution. It probably is
5751 -- not! It is OK for the new bound we are creating, but not for
5752 -- the old one??? Still if it never happens, no problem!
5754 Analyze_And_Resolve
(Bound
, Base_Type
(Par_T
));
5756 if Nkind
(Bound
) = N_Integer_Literal
5757 or else Nkind
(Bound
) = N_Real_Literal
5759 New_Bound
:= New_Copy
(Bound
);
5760 Set_Etype
(New_Bound
, Der_T
);
5761 Set_Analyzed
(New_Bound
);
5763 elsif Is_Entity_Name
(Bound
) then
5764 New_Bound
:= OK_Convert_To
(Der_T
, New_Copy
(Bound
));
5766 -- The following is almost certainly wrong. What business do we have
5767 -- relocating a node (Bound) that is presumably still attached to
5768 -- the tree elsewhere???
5771 New_Bound
:= OK_Convert_To
(Der_T
, Relocate_Node
(Bound
));
5774 Set_Etype
(New_Bound
, Der_T
);
5776 end Build_Scalar_Bound
;
5778 --------------------------------
5779 -- Build_Underlying_Full_View --
5780 --------------------------------
5782 procedure Build_Underlying_Full_View
5787 Loc
: constant Source_Ptr
:= Sloc
(N
);
5788 Subt
: constant Entity_Id
:=
5789 Make_Defining_Identifier
5790 (Loc
, New_External_Name
(Chars
(Typ
), 'S'));
5798 if Nkind
(N
) = N_Full_Type_Declaration
then
5799 Constr
:= Constraint
(Subtype_Indication
(Type_Definition
(N
)));
5801 -- ??? ??? is this assert right, I assume so otherwise Constr
5802 -- would not be defined below (this used to be an elsif)
5804 else pragma Assert
(Nkind
(N
) = N_Subtype_Declaration
);
5805 Constr
:= New_Copy_Tree
(Constraint
(Subtype_Indication
(N
)));
5808 -- If the constraint has discriminant associations, the discriminant
5809 -- entity is already set, but it denotes a discriminant of the new
5810 -- type, not the original parent, so it must be found anew.
5812 C
:= First
(Constraints
(Constr
));
5814 while Present
(C
) loop
5816 if Nkind
(C
) = N_Discriminant_Association
then
5817 Id
:= First
(Selector_Names
(C
));
5819 while Present
(Id
) loop
5820 Set_Original_Discriminant
(Id
, Empty
);
5828 Indic
:= Make_Subtype_Declaration
(Loc
,
5829 Defining_Identifier
=> Subt
,
5830 Subtype_Indication
=>
5831 Make_Subtype_Indication
(Loc
,
5832 Subtype_Mark
=> New_Reference_To
(Par
, Loc
),
5833 Constraint
=> New_Copy_Tree
(Constr
)));
5835 Insert_Before
(N
, Indic
);
5837 Set_Underlying_Full_View
(Typ
, Full_View
(Subt
));
5838 end Build_Underlying_Full_View
;
5840 -------------------------------
5841 -- Check_Abstract_Overriding --
5842 -------------------------------
5844 procedure Check_Abstract_Overriding
(T
: Entity_Id
) is
5851 Op_List
:= Primitive_Operations
(T
);
5853 -- Loop to check primitive operations
5855 Elmt
:= First_Elmt
(Op_List
);
5856 while Present
(Elmt
) loop
5857 Subp
:= Node
(Elmt
);
5859 -- Special exception, do not complain about failure to
5860 -- override _Input and _Output, since we always provide
5861 -- automatic overridings for these subprograms.
5863 if Is_Abstract
(Subp
)
5864 and then not Is_TSS
(Subp
, TSS_Stream_Input
)
5865 and then not Is_TSS
(Subp
, TSS_Stream_Output
)
5866 and then not Is_Abstract
(T
)
5868 if Present
(Alias
(Subp
)) then
5869 -- Only perform the check for a derived subprogram when
5870 -- the type has an explicit record extension. This avoids
5871 -- incorrectly flagging abstract subprograms for the case
5872 -- of a type without an extension derived from a formal type
5873 -- with a tagged actual (can occur within a private part).
5875 Type_Def
:= Type_Definition
(Parent
(T
));
5876 if Nkind
(Type_Def
) = N_Derived_Type_Definition
5877 and then Present
(Record_Extension_Part
(Type_Def
))
5880 ("type must be declared abstract or & overridden",
5885 ("abstract subprogram not allowed for type&",
5888 ("nonabstract type has abstract subprogram&",
5895 end Check_Abstract_Overriding
;
5897 ------------------------------------------------
5898 -- Check_Access_Discriminant_Requires_Limited --
5899 ------------------------------------------------
5901 procedure Check_Access_Discriminant_Requires_Limited
5906 -- A discriminant_specification for an access discriminant
5907 -- shall appear only in the declaration for a task or protected
5908 -- type, or for a type with the reserved word 'limited' in
5909 -- its definition or in one of its ancestors. (RM 3.7(10))
5911 if Nkind
(Discriminant_Type
(D
)) = N_Access_Definition
5912 and then not Is_Concurrent_Type
(Current_Scope
)
5913 and then not Is_Concurrent_Record_Type
(Current_Scope
)
5914 and then not Is_Limited_Record
(Current_Scope
)
5915 and then Ekind
(Current_Scope
) /= E_Limited_Private_Type
5918 ("access discriminants allowed only for limited types", Loc
);
5920 end Check_Access_Discriminant_Requires_Limited
;
5922 -----------------------------------
5923 -- Check_Aliased_Component_Types --
5924 -----------------------------------
5926 procedure Check_Aliased_Component_Types
(T
: Entity_Id
) is
5930 -- ??? Also need to check components of record extensions,
5931 -- but not components of protected types (which are always
5934 if not Is_Limited_Type
(T
) then
5935 if Ekind
(T
) = E_Record_Type
then
5936 C
:= First_Component
(T
);
5937 while Present
(C
) loop
5939 and then Has_Discriminants
(Etype
(C
))
5940 and then not Is_Constrained
(Etype
(C
))
5941 and then not In_Instance
5944 ("aliased component must be constrained ('R'M 3.6(11))",
5951 elsif Ekind
(T
) = E_Array_Type
then
5952 if Has_Aliased_Components
(T
)
5953 and then Has_Discriminants
(Component_Type
(T
))
5954 and then not Is_Constrained
(Component_Type
(T
))
5955 and then not In_Instance
5958 ("aliased component type must be constrained ('R'M 3.6(11))",
5963 end Check_Aliased_Component_Types
;
5965 ----------------------
5966 -- Check_Completion --
5967 ----------------------
5969 procedure Check_Completion
(Body_Id
: Node_Id
:= Empty
) is
5972 procedure Post_Error
;
5973 -- Post error message for lack of completion for entity E
5979 procedure Post_Error
is
5981 if not Comes_From_Source
(E
) then
5983 if Ekind
(E
) = E_Task_Type
5984 or else Ekind
(E
) = E_Protected_Type
5986 -- It may be an anonymous protected type created for a
5987 -- single variable. Post error on variable, if present.
5993 Var
:= First_Entity
(Current_Scope
);
5995 while Present
(Var
) loop
5996 exit when Etype
(Var
) = E
5997 and then Comes_From_Source
(Var
);
6002 if Present
(Var
) then
6009 -- If a generated entity has no completion, then either previous
6010 -- semantic errors have disabled the expansion phase, or else
6011 -- we had missing subunits, or else we are compiling without expan-
6012 -- sion, or else something is very wrong.
6014 if not Comes_From_Source
(E
) then
6016 (Serious_Errors_Detected
> 0
6017 or else Configurable_Run_Time_Violations
> 0
6018 or else Subunits_Missing
6019 or else not Expander_Active
);
6022 -- Here for source entity
6025 -- Here if no body to post the error message, so we post the error
6026 -- on the declaration that has no completion. This is not really
6027 -- the right place to post it, think about this later ???
6029 if No
(Body_Id
) then
6032 ("missing full declaration for }", Parent
(E
), E
);
6035 ("missing body for &", Parent
(E
), E
);
6038 -- Package body has no completion for a declaration that appears
6039 -- in the corresponding spec. Post error on the body, with a
6040 -- reference to the non-completed declaration.
6043 Error_Msg_Sloc
:= Sloc
(E
);
6047 ("missing full declaration for }!", Body_Id
, E
);
6049 elsif Is_Overloadable
(E
)
6050 and then Current_Entity_In_Scope
(E
) /= E
6052 -- It may be that the completion is mistyped and appears
6053 -- as a distinct overloading of the entity.
6056 Candidate
: constant Entity_Id
:=
6057 Current_Entity_In_Scope
(E
);
6058 Decl
: constant Node_Id
:=
6059 Unit_Declaration_Node
(Candidate
);
6062 if Is_Overloadable
(Candidate
)
6063 and then Ekind
(Candidate
) = Ekind
(E
)
6064 and then Nkind
(Decl
) = N_Subprogram_Body
6065 and then Acts_As_Spec
(Decl
)
6067 Check_Type_Conformant
(Candidate
, E
);
6070 Error_Msg_NE
("missing body for & declared#!",
6075 Error_Msg_NE
("missing body for & declared#!",
6082 -- Start processing for Check_Completion
6085 E
:= First_Entity
(Current_Scope
);
6086 while Present
(E
) loop
6087 if Is_Intrinsic_Subprogram
(E
) then
6090 -- The following situation requires special handling: a child
6091 -- unit that appears in the context clause of the body of its
6094 -- procedure Parent.Child (...);
6096 -- with Parent.Child;
6097 -- package body Parent is
6099 -- Here Parent.Child appears as a local entity, but should not
6100 -- be flagged as requiring completion, because it is a
6101 -- compilation unit.
6103 elsif Ekind
(E
) = E_Function
6104 or else Ekind
(E
) = E_Procedure
6105 or else Ekind
(E
) = E_Generic_Function
6106 or else Ekind
(E
) = E_Generic_Procedure
6108 if not Has_Completion
(E
)
6109 and then not Is_Abstract
(E
)
6110 and then Nkind
(Parent
(Unit_Declaration_Node
(E
))) /=
6112 and then Chars
(E
) /= Name_uSize
6117 elsif Is_Entry
(E
) then
6118 if not Has_Completion
(E
) and then
6119 (Ekind
(Scope
(E
)) = E_Protected_Object
6120 or else Ekind
(Scope
(E
)) = E_Protected_Type
)
6125 elsif Is_Package
(E
) then
6126 if Unit_Requires_Body
(E
) then
6127 if not Has_Completion
(E
)
6128 and then Nkind
(Parent
(Unit_Declaration_Node
(E
))) /=
6134 elsif not Is_Child_Unit
(E
) then
6135 May_Need_Implicit_Body
(E
);
6138 elsif Ekind
(E
) = E_Incomplete_Type
6139 and then No
(Underlying_Type
(E
))
6143 elsif (Ekind
(E
) = E_Task_Type
or else
6144 Ekind
(E
) = E_Protected_Type
)
6145 and then not Has_Completion
(E
)
6149 -- A single task declared in the current scope is
6150 -- a constant, verify that the body of its anonymous
6151 -- type is in the same scope. If the task is defined
6152 -- elsewhere, this may be a renaming declaration for
6153 -- which no completion is needed.
6155 elsif Ekind
(E
) = E_Constant
6156 and then Ekind
(Etype
(E
)) = E_Task_Type
6157 and then not Has_Completion
(Etype
(E
))
6158 and then Scope
(Etype
(E
)) = Current_Scope
6162 elsif Ekind
(E
) = E_Protected_Object
6163 and then not Has_Completion
(Etype
(E
))
6167 elsif Ekind
(E
) = E_Record_Type
then
6168 if Is_Tagged_Type
(E
) then
6169 Check_Abstract_Overriding
(E
);
6172 Check_Aliased_Component_Types
(E
);
6174 elsif Ekind
(E
) = E_Array_Type
then
6175 Check_Aliased_Component_Types
(E
);
6181 end Check_Completion
;
6183 ----------------------------
6184 -- Check_Delta_Expression --
6185 ----------------------------
6187 procedure Check_Delta_Expression
(E
: Node_Id
) is
6189 if not (Is_Real_Type
(Etype
(E
))) then
6190 Wrong_Type
(E
, Any_Real
);
6192 elsif not Is_OK_Static_Expression
(E
) then
6193 Flag_Non_Static_Expr
6194 ("non-static expression used for delta value!", E
);
6196 elsif not UR_Is_Positive
(Expr_Value_R
(E
)) then
6197 Error_Msg_N
("delta expression must be positive", E
);
6203 -- If any of above errors occurred, then replace the incorrect
6204 -- expression by the real 0.1, which should prevent further errors.
6207 Make_Real_Literal
(Sloc
(E
), Ureal_Tenth
));
6208 Analyze_And_Resolve
(E
, Standard_Float
);
6210 end Check_Delta_Expression
;
6212 -----------------------------
6213 -- Check_Digits_Expression --
6214 -----------------------------
6216 procedure Check_Digits_Expression
(E
: Node_Id
) is
6218 if not (Is_Integer_Type
(Etype
(E
))) then
6219 Wrong_Type
(E
, Any_Integer
);
6221 elsif not Is_OK_Static_Expression
(E
) then
6222 Flag_Non_Static_Expr
6223 ("non-static expression used for digits value!", E
);
6225 elsif Expr_Value
(E
) <= 0 then
6226 Error_Msg_N
("digits value must be greater than zero", E
);
6232 -- If any of above errors occurred, then replace the incorrect
6233 -- expression by the integer 1, which should prevent further errors.
6235 Rewrite
(E
, Make_Integer_Literal
(Sloc
(E
), 1));
6236 Analyze_And_Resolve
(E
, Standard_Integer
);
6238 end Check_Digits_Expression
;
6240 --------------------------
6241 -- Check_Initialization --
6242 --------------------------
6244 procedure Check_Initialization
(T
: Entity_Id
; Exp
: Node_Id
) is
6246 if (Is_Limited_Type
(T
)
6247 or else Is_Limited_Composite
(T
))
6248 and then not In_Instance
6249 and then not In_Inlined_Body
6251 -- Ada0Y (AI-287): Relax the strictness of the front-end in case of
6252 -- limited aggregates and extension aggregates.
6254 if Extensions_Allowed
6255 and then (Nkind
(Exp
) = N_Aggregate
6256 or else Nkind
(Exp
) = N_Extension_Aggregate
)
6261 ("cannot initialize entities of limited type", Exp
);
6262 Explain_Limited_Type
(T
, Exp
);
6265 end Check_Initialization
;
6267 ------------------------------------
6268 -- Check_Or_Process_Discriminants --
6269 ------------------------------------
6271 -- If an incomplete or private type declaration was already given for
6272 -- the type, the discriminants may have already been processed if they
6273 -- were present on the incomplete declaration. In this case a full
6274 -- conformance check is performed otherwise just process them.
6276 procedure Check_Or_Process_Discriminants
6279 Prev
: Entity_Id
:= Empty
)
6282 if Has_Discriminants
(T
) then
6284 -- Make the discriminants visible to component declarations.
6287 D
: Entity_Id
:= First_Discriminant
(T
);
6291 while Present
(D
) loop
6292 Prev
:= Current_Entity
(D
);
6293 Set_Current_Entity
(D
);
6294 Set_Is_Immediately_Visible
(D
);
6295 Set_Homonym
(D
, Prev
);
6297 -- This restriction gets applied to the full type here; it
6298 -- has already been applied earlier to the partial view
6300 Check_Access_Discriminant_Requires_Limited
(Parent
(D
), N
);
6302 Next_Discriminant
(D
);
6306 elsif Present
(Discriminant_Specifications
(N
)) then
6307 Process_Discriminants
(N
, Prev
);
6309 end Check_Or_Process_Discriminants
;
6311 ----------------------
6312 -- Check_Real_Bound --
6313 ----------------------
6315 procedure Check_Real_Bound
(Bound
: Node_Id
) is
6317 if not Is_Real_Type
(Etype
(Bound
)) then
6319 ("bound in real type definition must be of real type", Bound
);
6321 elsif not Is_OK_Static_Expression
(Bound
) then
6322 Flag_Non_Static_Expr
6323 ("non-static expression used for real type bound!", Bound
);
6330 (Bound
, Make_Real_Literal
(Sloc
(Bound
), Ureal_0
));
6332 Resolve
(Bound
, Standard_Float
);
6333 end Check_Real_Bound
;
6335 ------------------------------
6336 -- Complete_Private_Subtype --
6337 ------------------------------
6339 procedure Complete_Private_Subtype
6342 Full_Base
: Entity_Id
;
6343 Related_Nod
: Node_Id
)
6345 Save_Next_Entity
: Entity_Id
;
6346 Save_Homonym
: Entity_Id
;
6349 -- Set semantic attributes for (implicit) private subtype completion.
6350 -- If the full type has no discriminants, then it is a copy of the full
6351 -- view of the base. Otherwise, it is a subtype of the base with a
6352 -- possible discriminant constraint. Save and restore the original
6353 -- Next_Entity field of full to ensure that the calls to Copy_Node
6354 -- do not corrupt the entity chain.
6356 -- Note that the type of the full view is the same entity as the
6357 -- type of the partial view. In this fashion, the subtype has
6358 -- access to the correct view of the parent.
6360 Save_Next_Entity
:= Next_Entity
(Full
);
6361 Save_Homonym
:= Homonym
(Priv
);
6363 case Ekind
(Full_Base
) is
6365 when E_Record_Type |
6371 Copy_Node
(Priv
, Full
);
6373 Set_Has_Discriminants
(Full
, Has_Discriminants
(Full_Base
));
6374 Set_First_Entity
(Full
, First_Entity
(Full_Base
));
6375 Set_Last_Entity
(Full
, Last_Entity
(Full_Base
));
6378 Copy_Node
(Full_Base
, Full
);
6379 Set_Chars
(Full
, Chars
(Priv
));
6380 Conditional_Delay
(Full
, Priv
);
6381 Set_Sloc
(Full
, Sloc
(Priv
));
6385 Set_Next_Entity
(Full
, Save_Next_Entity
);
6386 Set_Homonym
(Full
, Save_Homonym
);
6387 Set_Associated_Node_For_Itype
(Full
, Related_Nod
);
6389 -- Set common attributes for all subtypes.
6391 Set_Ekind
(Full
, Subtype_Kind
(Ekind
(Full_Base
)));
6393 -- The Etype of the full view is inconsistent. Gigi needs to see the
6394 -- structural full view, which is what the current scheme gives:
6395 -- the Etype of the full view is the etype of the full base. However,
6396 -- if the full base is a derived type, the full view then looks like
6397 -- a subtype of the parent, not a subtype of the full base. If instead
6400 -- Set_Etype (Full, Full_Base);
6402 -- then we get inconsistencies in the front-end (confusion between
6403 -- views). Several outstanding bugs are related to this.
6405 Set_Is_First_Subtype
(Full
, False);
6406 Set_Scope
(Full
, Scope
(Priv
));
6407 Set_Size_Info
(Full
, Full_Base
);
6408 Set_RM_Size
(Full
, RM_Size
(Full_Base
));
6409 Set_Is_Itype
(Full
);
6411 -- A subtype of a private-type-without-discriminants, whose full-view
6412 -- has discriminants with default expressions, is not constrained!
6414 if not Has_Discriminants
(Priv
) then
6415 Set_Is_Constrained
(Full
, Is_Constrained
(Full_Base
));
6417 if Has_Discriminants
(Full_Base
) then
6418 Set_Discriminant_Constraint
6419 (Full
, Discriminant_Constraint
(Full_Base
));
6423 Set_First_Rep_Item
(Full
, First_Rep_Item
(Full_Base
));
6424 Set_Depends_On_Private
(Full
, Has_Private_Component
(Full
));
6426 -- Freeze the private subtype entity if its parent is delayed,
6427 -- and not already frozen. We skip this processing if the type
6428 -- is an anonymous subtype of a record component, or is the
6429 -- corresponding record of a protected type, since ???
6431 if not Is_Type
(Scope
(Full
)) then
6432 Set_Has_Delayed_Freeze
(Full
,
6433 Has_Delayed_Freeze
(Full_Base
)
6434 and then (not Is_Frozen
(Full_Base
)));
6437 Set_Freeze_Node
(Full
, Empty
);
6438 Set_Is_Frozen
(Full
, False);
6439 Set_Full_View
(Priv
, Full
);
6441 if Has_Discriminants
(Full
) then
6442 Set_Stored_Constraint_From_Discriminant_Constraint
(Full
);
6443 Set_Stored_Constraint
(Priv
, Stored_Constraint
(Full
));
6444 if Has_Unknown_Discriminants
(Full
) then
6445 Set_Discriminant_Constraint
(Full
, No_Elist
);
6449 if Ekind
(Full_Base
) = E_Record_Type
6450 and then Has_Discriminants
(Full_Base
)
6451 and then Has_Discriminants
(Priv
) -- might not, if errors
6452 and then not Is_Empty_Elmt_List
(Discriminant_Constraint
(Priv
))
6454 Create_Constrained_Components
6455 (Full
, Related_Nod
, Full_Base
, Discriminant_Constraint
(Priv
));
6457 -- If the full base is itself derived from private, build a congruent
6458 -- subtype of its underlying type, for use by the back end.
6460 elsif Ekind
(Full_Base
) in Private_Kind
6461 and then Is_Derived_Type
(Full_Base
)
6462 and then Has_Discriminants
(Full_Base
)
6464 Nkind
(Subtype_Indication
(Parent
(Priv
))) = N_Subtype_Indication
6466 Build_Underlying_Full_View
(Parent
(Priv
), Full
, Etype
(Full_Base
));
6468 elsif Is_Record_Type
(Full_Base
) then
6470 -- Show Full is simply a renaming of Full_Base.
6472 Set_Cloned_Subtype
(Full
, Full_Base
);
6475 -- It is unsafe to share to bounds of a scalar type, because the
6476 -- Itype is elaborated on demand, and if a bound is non-static
6477 -- then different orders of elaboration in different units will
6478 -- lead to different external symbols.
6480 if Is_Scalar_Type
(Full_Base
) then
6481 Set_Scalar_Range
(Full
,
6482 Make_Range
(Sloc
(Related_Nod
),
6484 Duplicate_Subexpr_No_Checks
(Type_Low_Bound
(Full_Base
)),
6486 Duplicate_Subexpr_No_Checks
(Type_High_Bound
(Full_Base
))));
6488 -- This completion inherits the bounds of the full parent, but if
6489 -- the parent is an unconstrained floating point type, so is the
6492 if Is_Floating_Point_Type
(Full_Base
) then
6493 Set_Includes_Infinities
6494 (Scalar_Range
(Full
), Has_Infinities
(Full_Base
));
6498 -- ??? It seems that a lot of fields are missing that should be
6499 -- copied from Full_Base to Full. Here are some that are introduced
6500 -- in a non-disruptive way but a cleanup is necessary.
6502 if Is_Tagged_Type
(Full_Base
) then
6503 Set_Is_Tagged_Type
(Full
);
6504 Set_Primitive_Operations
(Full
, Primitive_Operations
(Full_Base
));
6505 Set_Class_Wide_Type
(Full
, Class_Wide_Type
(Full_Base
));
6507 elsif Is_Concurrent_Type
(Full_Base
) then
6508 if Has_Discriminants
(Full
)
6509 and then Present
(Corresponding_Record_Type
(Full_Base
))
6511 Set_Corresponding_Record_Type
(Full
,
6512 Constrain_Corresponding_Record
6513 (Full
, Corresponding_Record_Type
(Full_Base
),
6514 Related_Nod
, Full_Base
));
6517 Set_Corresponding_Record_Type
(Full
,
6518 Corresponding_Record_Type
(Full_Base
));
6522 end Complete_Private_Subtype
;
6524 ----------------------------
6525 -- Constant_Redeclaration --
6526 ----------------------------
6528 procedure Constant_Redeclaration
6533 Prev
: constant Entity_Id
:= Current_Entity_In_Scope
(Id
);
6534 Obj_Def
: constant Node_Id
:= Object_Definition
(N
);
6537 procedure Check_Recursive_Declaration
(Typ
: Entity_Id
);
6538 -- If deferred constant is an access type initialized with an
6539 -- allocator, check whether there is an illegal recursion in the
6540 -- definition, through a default value of some record subcomponent.
6541 -- This is normally detected when generating init procs, but requires
6542 -- this additional mechanism when expansion is disabled.
6544 ---------------------------------
6545 -- Check_Recursive_Declaration --
6546 ---------------------------------
6548 procedure Check_Recursive_Declaration
(Typ
: Entity_Id
) is
6552 if Is_Record_Type
(Typ
) then
6553 Comp
:= First_Component
(Typ
);
6555 while Present
(Comp
) loop
6556 if Comes_From_Source
(Comp
) then
6557 if Present
(Expression
(Parent
(Comp
)))
6558 and then Is_Entity_Name
(Expression
(Parent
(Comp
)))
6559 and then Entity
(Expression
(Parent
(Comp
))) = Prev
6561 Error_Msg_Sloc
:= Sloc
(Parent
(Comp
));
6563 ("illegal circularity with declaration for&#",
6567 elsif Is_Record_Type
(Etype
(Comp
)) then
6568 Check_Recursive_Declaration
(Etype
(Comp
));
6572 Next_Component
(Comp
);
6575 end Check_Recursive_Declaration
;
6577 -- Start of processing for Constant_Redeclaration
6580 if Nkind
(Parent
(Prev
)) = N_Object_Declaration
then
6581 if Nkind
(Object_Definition
6582 (Parent
(Prev
))) = N_Subtype_Indication
6584 -- Find type of new declaration. The constraints of the two
6585 -- views must match statically, but there is no point in
6586 -- creating an itype for the full view.
6588 if Nkind
(Obj_Def
) = N_Subtype_Indication
then
6589 Find_Type
(Subtype_Mark
(Obj_Def
));
6590 New_T
:= Entity
(Subtype_Mark
(Obj_Def
));
6593 Find_Type
(Obj_Def
);
6594 New_T
:= Entity
(Obj_Def
);
6600 -- The full view may impose a constraint, even if the partial
6601 -- view does not, so construct the subtype.
6603 New_T
:= Find_Type_Of_Object
(Obj_Def
, N
);
6608 -- Current declaration is illegal, diagnosed below in Enter_Name.
6614 -- If previous full declaration exists, or if a homograph is present,
6615 -- let Enter_Name handle it, either with an error, or with the removal
6616 -- of an overridden implicit subprogram.
6618 if Ekind
(Prev
) /= E_Constant
6619 or else Present
(Expression
(Parent
(Prev
)))
6620 or else Present
(Full_View
(Prev
))
6624 -- Verify that types of both declarations match.
6626 elsif Base_Type
(Etype
(Prev
)) /= Base_Type
(New_T
) then
6627 Error_Msg_Sloc
:= Sloc
(Prev
);
6628 Error_Msg_N
("type does not match declaration#", N
);
6629 Set_Full_View
(Prev
, Id
);
6630 Set_Etype
(Id
, Any_Type
);
6632 -- If so, process the full constant declaration
6635 Set_Full_View
(Prev
, Id
);
6636 Set_Is_Public
(Id
, Is_Public
(Prev
));
6637 Set_Is_Internal
(Id
);
6638 Append_Entity
(Id
, Current_Scope
);
6640 -- Check ALIASED present if present before (RM 7.4(7))
6642 if Is_Aliased
(Prev
)
6643 and then not Aliased_Present
(N
)
6645 Error_Msg_Sloc
:= Sloc
(Prev
);
6646 Error_Msg_N
("ALIASED required (see declaration#)", N
);
6649 -- Check that placement is in private part and that the incomplete
6650 -- declaration appeared in the visible part.
6652 if Ekind
(Current_Scope
) = E_Package
6653 and then not In_Private_Part
(Current_Scope
)
6655 Error_Msg_Sloc
:= Sloc
(Prev
);
6656 Error_Msg_N
("full constant for declaration#"
6657 & " must be in private part", N
);
6659 elsif Ekind
(Current_Scope
) = E_Package
6660 and then List_Containing
(Parent
(Prev
))
6661 /= Visible_Declarations
6662 (Specification
(Unit_Declaration_Node
(Current_Scope
)))
6665 ("deferred constant must be declared in visible part",
6669 if Is_Access_Type
(T
)
6670 and then Nkind
(Expression
(N
)) = N_Allocator
6672 Check_Recursive_Declaration
(Designated_Type
(T
));
6675 end Constant_Redeclaration
;
6677 ----------------------
6678 -- Constrain_Access --
6679 ----------------------
6681 procedure Constrain_Access
6682 (Def_Id
: in out Entity_Id
;
6684 Related_Nod
: Node_Id
)
6686 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
6687 Desig_Type
: constant Entity_Id
:= Designated_Type
(T
);
6688 Desig_Subtype
: Entity_Id
:= Create_Itype
(E_Void
, Related_Nod
);
6689 Constraint_OK
: Boolean := True;
6692 if Is_Array_Type
(Desig_Type
) then
6693 Constrain_Array
(Desig_Subtype
, S
, Related_Nod
, Def_Id
, 'P');
6695 elsif (Is_Record_Type
(Desig_Type
)
6696 or else Is_Incomplete_Or_Private_Type
(Desig_Type
))
6697 and then not Is_Constrained
(Desig_Type
)
6699 -- ??? The following code is a temporary kludge to ignore
6700 -- discriminant constraint on access type if
6701 -- it is constraining the current record. Avoid creating the
6702 -- implicit subtype of the record we are currently compiling
6703 -- since right now, we cannot handle these.
6704 -- For now, just return the access type itself.
6706 if Desig_Type
= Current_Scope
6707 and then No
(Def_Id
)
6709 Set_Ekind
(Desig_Subtype
, E_Record_Subtype
);
6710 Def_Id
:= Entity
(Subtype_Mark
(S
));
6712 -- This call added to ensure that the constraint is
6713 -- analyzed (needed for a B test). Note that we
6714 -- still return early from this procedure to avoid
6715 -- recursive processing. ???
6717 Constrain_Discriminated_Type
6718 (Desig_Subtype
, S
, Related_Nod
, For_Access
=> True);
6723 if Ekind
(T
) = E_General_Access_Type
6724 and then Has_Private_Declaration
(Desig_Type
)
6725 and then In_Open_Scopes
(Scope
(Desig_Type
))
6727 -- Enforce rule that the constraint is illegal if there is
6728 -- an unconstrained view of the designated type. This means
6729 -- that the partial view (either a private type declaration or
6730 -- a derivation from a private type) has no discriminants.
6731 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
6732 -- by ACATS B371001).
6735 Pack
: constant Node_Id
:=
6736 Unit_Declaration_Node
(Scope
(Desig_Type
));
6741 if Nkind
(Pack
) = N_Package_Declaration
then
6742 Decls
:= Visible_Declarations
(Specification
(Pack
));
6743 Decl
:= First
(Decls
);
6745 while Present
(Decl
) loop
6746 if (Nkind
(Decl
) = N_Private_Type_Declaration
6748 Chars
(Defining_Identifier
(Decl
)) =
6752 (Nkind
(Decl
) = N_Full_Type_Declaration
6754 Chars
(Defining_Identifier
(Decl
)) =
6756 and then Is_Derived_Type
(Desig_Type
)
6758 Has_Private_Declaration
(Etype
(Desig_Type
)))
6760 if No
(Discriminant_Specifications
(Decl
)) then
6762 ("cannot constrain general access type " &
6763 "if designated type has unconstrained view", S
);
6775 Constrain_Discriminated_Type
(Desig_Subtype
, S
, Related_Nod
,
6776 For_Access
=> True);
6778 elsif (Is_Task_Type
(Desig_Type
)
6779 or else Is_Protected_Type
(Desig_Type
))
6780 and then not Is_Constrained
(Desig_Type
)
6782 Constrain_Concurrent
6783 (Desig_Subtype
, S
, Related_Nod
, Desig_Type
, ' ');
6786 Error_Msg_N
("invalid constraint on access type", S
);
6787 Desig_Subtype
:= Desig_Type
; -- Ignore invalid constraint.
6788 Constraint_OK
:= False;
6792 Def_Id
:= Create_Itype
(E_Access_Subtype
, Related_Nod
);
6794 Set_Ekind
(Def_Id
, E_Access_Subtype
);
6797 if Constraint_OK
then
6798 Set_Etype
(Def_Id
, Base_Type
(T
));
6800 if Is_Private_Type
(Desig_Type
) then
6801 Prepare_Private_Subtype_Completion
(Desig_Subtype
, Related_Nod
);
6804 Set_Etype
(Def_Id
, Any_Type
);
6807 Set_Size_Info
(Def_Id
, T
);
6808 Set_Is_Constrained
(Def_Id
, Constraint_OK
);
6809 Set_Directly_Designated_Type
(Def_Id
, Desig_Subtype
);
6810 Set_Depends_On_Private
(Def_Id
, Has_Private_Component
(Def_Id
));
6811 Set_Is_Access_Constant
(Def_Id
, Is_Access_Constant
(T
));
6813 -- Itypes created for constrained record components do not receive
6814 -- a freeze node, they are elaborated when first seen.
6816 if not Is_Record_Type
(Current_Scope
) then
6817 Conditional_Delay
(Def_Id
, T
);
6819 end Constrain_Access
;
6821 ---------------------
6822 -- Constrain_Array --
6823 ---------------------
6825 procedure Constrain_Array
6826 (Def_Id
: in out Entity_Id
;
6828 Related_Nod
: Node_Id
;
6829 Related_Id
: Entity_Id
;
6832 C
: constant Node_Id
:= Constraint
(SI
);
6833 Number_Of_Constraints
: Nat
:= 0;
6836 Constraint_OK
: Boolean := True;
6839 T
:= Entity
(Subtype_Mark
(SI
));
6841 if Ekind
(T
) in Access_Kind
then
6842 T
:= Designated_Type
(T
);
6845 -- If an index constraint follows a subtype mark in a subtype indication
6846 -- then the type or subtype denoted by the subtype mark must not already
6847 -- impose an index constraint. The subtype mark must denote either an
6848 -- unconstrained array type or an access type whose designated type
6849 -- is such an array type... (RM 3.6.1)
6851 if Is_Constrained
(T
) then
6853 ("array type is already constrained", Subtype_Mark
(SI
));
6854 Constraint_OK
:= False;
6857 S
:= First
(Constraints
(C
));
6859 while Present
(S
) loop
6860 Number_Of_Constraints
:= Number_Of_Constraints
+ 1;
6864 -- In either case, the index constraint must provide a discrete
6865 -- range for each index of the array type and the type of each
6866 -- discrete range must be the same as that of the corresponding
6867 -- index. (RM 3.6.1)
6869 if Number_Of_Constraints
/= Number_Dimensions
(T
) then
6870 Error_Msg_NE
("incorrect number of index constraints for }", C
, T
);
6871 Constraint_OK
:= False;
6874 S
:= First
(Constraints
(C
));
6875 Index
:= First_Index
(T
);
6878 -- Apply constraints to each index type
6880 for J
in 1 .. Number_Of_Constraints
loop
6881 Constrain_Index
(Index
, S
, Related_Nod
, Related_Id
, Suffix
, J
);
6891 Create_Itype
(E_Array_Subtype
, Related_Nod
, Related_Id
, Suffix
);
6892 Set_Parent
(Def_Id
, Related_Nod
);
6895 Set_Ekind
(Def_Id
, E_Array_Subtype
);
6898 Set_Size_Info
(Def_Id
, (T
));
6899 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
6900 Set_Etype
(Def_Id
, Base_Type
(T
));
6902 if Constraint_OK
then
6903 Set_First_Index
(Def_Id
, First
(Constraints
(C
)));
6906 Set_Is_Constrained
(Def_Id
, True);
6907 Set_Is_Aliased
(Def_Id
, Is_Aliased
(T
));
6908 Set_Depends_On_Private
(Def_Id
, Has_Private_Component
(Def_Id
));
6910 Set_Is_Private_Composite
(Def_Id
, Is_Private_Composite
(T
));
6911 Set_Is_Limited_Composite
(Def_Id
, Is_Limited_Composite
(T
));
6913 -- If the subtype is not that of a record component, build a freeze
6914 -- node if parent still needs one.
6916 -- If the subtype is not that of a record component, make sure
6917 -- that the Depends_On_Private status is set (explanation ???)
6918 -- and also that a conditional delay is set.
6920 if not Is_Type
(Scope
(Def_Id
)) then
6921 Set_Depends_On_Private
(Def_Id
, Depends_On_Private
(T
));
6922 Conditional_Delay
(Def_Id
, T
);
6925 end Constrain_Array
;
6927 ------------------------------
6928 -- Constrain_Component_Type --
6929 ------------------------------
6931 function Constrain_Component_Type
6932 (Compon_Type
: Entity_Id
;
6933 Constrained_Typ
: Entity_Id
;
6934 Related_Node
: Node_Id
;
6936 Constraints
: Elist_Id
) return Entity_Id
6938 Loc
: constant Source_Ptr
:= Sloc
(Constrained_Typ
);
6940 function Build_Constrained_Array_Type
6941 (Old_Type
: Entity_Id
) return Entity_Id
;
6942 -- If Old_Type is an array type, one of whose indices is
6943 -- constrained by a discriminant, build an Itype whose constraint
6944 -- replaces the discriminant with its value in the constraint.
6946 function Build_Constrained_Discriminated_Type
6947 (Old_Type
: Entity_Id
) return Entity_Id
;
6948 -- Ditto for record components.
6950 function Build_Constrained_Access_Type
6951 (Old_Type
: Entity_Id
) return Entity_Id
;
6952 -- Ditto for access types. Makes use of previous two functions, to
6953 -- constrain designated type.
6955 function Build_Subtype
(T
: Entity_Id
; C
: List_Id
) return Entity_Id
;
6956 -- T is an array or discriminated type, C is a list of constraints
6957 -- that apply to T. This routine builds the constrained subtype.
6959 function Is_Discriminant
(Expr
: Node_Id
) return Boolean;
6960 -- Returns True if Expr is a discriminant.
6962 function Get_Discr_Value
(Discrim
: Entity_Id
) return Node_Id
;
6963 -- Find the value of discriminant Discrim in Constraint.
6965 -----------------------------------
6966 -- Build_Constrained_Access_Type --
6967 -----------------------------------
6969 function Build_Constrained_Access_Type
6970 (Old_Type
: Entity_Id
) return Entity_Id
6972 Desig_Type
: constant Entity_Id
:= Designated_Type
(Old_Type
);
6974 Desig_Subtype
: Entity_Id
;
6978 -- if the original access type was not embedded in the enclosing
6979 -- type definition, there is no need to produce a new access
6980 -- subtype. In fact every access type with an explicit constraint
6981 -- generates an itype whose scope is the enclosing record.
6983 if not Is_Type
(Scope
(Old_Type
)) then
6986 elsif Is_Array_Type
(Desig_Type
) then
6987 Desig_Subtype
:= Build_Constrained_Array_Type
(Desig_Type
);
6989 elsif Has_Discriminants
(Desig_Type
) then
6991 -- This may be an access type to an enclosing record type for
6992 -- which we are constructing the constrained components. Return
6993 -- the enclosing record subtype. This is not always correct,
6994 -- but avoids infinite recursion. ???
6996 Desig_Subtype
:= Any_Type
;
6998 for J
in reverse 0 .. Scope_Stack
.Last
loop
6999 Scop
:= Scope_Stack
.Table
(J
).Entity
;
7002 and then Base_Type
(Scop
) = Base_Type
(Desig_Type
)
7004 Desig_Subtype
:= Scop
;
7007 exit when not Is_Type
(Scop
);
7010 if Desig_Subtype
= Any_Type
then
7012 Build_Constrained_Discriminated_Type
(Desig_Type
);
7019 if Desig_Subtype
/= Desig_Type
then
7020 -- The Related_Node better be here or else we won't be able
7021 -- to attach new itypes to a node in the tree.
7023 pragma Assert
(Present
(Related_Node
));
7025 Itype
:= Create_Itype
(E_Access_Subtype
, Related_Node
);
7027 Set_Etype
(Itype
, Base_Type
(Old_Type
));
7028 Set_Size_Info
(Itype
, (Old_Type
));
7029 Set_Directly_Designated_Type
(Itype
, Desig_Subtype
);
7030 Set_Depends_On_Private
(Itype
, Has_Private_Component
7032 Set_Is_Access_Constant
(Itype
, Is_Access_Constant
7035 -- The new itype needs freezing when it depends on a not frozen
7036 -- type and the enclosing subtype needs freezing.
7038 if Has_Delayed_Freeze
(Constrained_Typ
)
7039 and then not Is_Frozen
(Constrained_Typ
)
7041 Conditional_Delay
(Itype
, Base_Type
(Old_Type
));
7049 end Build_Constrained_Access_Type
;
7051 ----------------------------------
7052 -- Build_Constrained_Array_Type --
7053 ----------------------------------
7055 function Build_Constrained_Array_Type
7056 (Old_Type
: Entity_Id
) return Entity_Id
7060 Old_Index
: Node_Id
;
7061 Range_Node
: Node_Id
;
7062 Constr_List
: List_Id
;
7064 Need_To_Create_Itype
: Boolean := False;
7067 Old_Index
:= First_Index
(Old_Type
);
7068 while Present
(Old_Index
) loop
7069 Get_Index_Bounds
(Old_Index
, Lo_Expr
, Hi_Expr
);
7071 if Is_Discriminant
(Lo_Expr
)
7072 or else Is_Discriminant
(Hi_Expr
)
7074 Need_To_Create_Itype
:= True;
7077 Next_Index
(Old_Index
);
7080 if Need_To_Create_Itype
then
7081 Constr_List
:= New_List
;
7083 Old_Index
:= First_Index
(Old_Type
);
7084 while Present
(Old_Index
) loop
7085 Get_Index_Bounds
(Old_Index
, Lo_Expr
, Hi_Expr
);
7087 if Is_Discriminant
(Lo_Expr
) then
7088 Lo_Expr
:= Get_Discr_Value
(Lo_Expr
);
7091 if Is_Discriminant
(Hi_Expr
) then
7092 Hi_Expr
:= Get_Discr_Value
(Hi_Expr
);
7097 (Loc
, New_Copy_Tree
(Lo_Expr
), New_Copy_Tree
(Hi_Expr
));
7099 Append
(Range_Node
, To
=> Constr_List
);
7101 Next_Index
(Old_Index
);
7104 return Build_Subtype
(Old_Type
, Constr_List
);
7109 end Build_Constrained_Array_Type
;
7111 ------------------------------------------
7112 -- Build_Constrained_Discriminated_Type --
7113 ------------------------------------------
7115 function Build_Constrained_Discriminated_Type
7116 (Old_Type
: Entity_Id
) return Entity_Id
7119 Constr_List
: List_Id
;
7120 Old_Constraint
: Elmt_Id
;
7122 Need_To_Create_Itype
: Boolean := False;
7125 Old_Constraint
:= First_Elmt
(Discriminant_Constraint
(Old_Type
));
7126 while Present
(Old_Constraint
) loop
7127 Expr
:= Node
(Old_Constraint
);
7129 if Is_Discriminant
(Expr
) then
7130 Need_To_Create_Itype
:= True;
7133 Next_Elmt
(Old_Constraint
);
7136 if Need_To_Create_Itype
then
7137 Constr_List
:= New_List
;
7139 Old_Constraint
:= First_Elmt
(Discriminant_Constraint
(Old_Type
));
7140 while Present
(Old_Constraint
) loop
7141 Expr
:= Node
(Old_Constraint
);
7143 if Is_Discriminant
(Expr
) then
7144 Expr
:= Get_Discr_Value
(Expr
);
7147 Append
(New_Copy_Tree
(Expr
), To
=> Constr_List
);
7149 Next_Elmt
(Old_Constraint
);
7152 return Build_Subtype
(Old_Type
, Constr_List
);
7157 end Build_Constrained_Discriminated_Type
;
7163 function Build_Subtype
(T
: Entity_Id
; C
: List_Id
) return Entity_Id
is
7165 Subtyp_Decl
: Node_Id
;
7167 Btyp
: Entity_Id
:= Base_Type
(T
);
7170 -- The Related_Node better be here or else we won't be able
7171 -- to attach new itypes to a node in the tree.
7173 pragma Assert
(Present
(Related_Node
));
7175 -- If the view of the component's type is incomplete or private
7176 -- with unknown discriminants, then the constraint must be applied
7177 -- to the full type.
7179 if Has_Unknown_Discriminants
(Btyp
)
7180 and then Present
(Underlying_Type
(Btyp
))
7182 Btyp
:= Underlying_Type
(Btyp
);
7186 Make_Subtype_Indication
(Loc
,
7187 Subtype_Mark
=> New_Occurrence_Of
(Btyp
, Loc
),
7188 Constraint
=> Make_Index_Or_Discriminant_Constraint
(Loc
, C
));
7190 Def_Id
:= Create_Itype
(Ekind
(T
), Related_Node
);
7193 Make_Subtype_Declaration
(Loc
,
7194 Defining_Identifier
=> Def_Id
,
7195 Subtype_Indication
=> Indic
);
7196 Set_Parent
(Subtyp_Decl
, Parent
(Related_Node
));
7198 -- Itypes must be analyzed with checks off (see itypes.ads).
7200 Analyze
(Subtyp_Decl
, Suppress
=> All_Checks
);
7205 ---------------------
7206 -- Get_Discr_Value --
7207 ---------------------
7209 function Get_Discr_Value
(Discrim
: Entity_Id
) return Node_Id
is
7210 D
: Entity_Id
:= First_Discriminant
(Typ
);
7211 E
: Elmt_Id
:= First_Elmt
(Constraints
);
7215 -- The discriminant may be declared for the type, in which case we
7216 -- find it by iterating over the list of discriminants. If the
7217 -- discriminant is inherited from a parent type, it appears as the
7218 -- corresponding discriminant of the current type. This will be the
7219 -- case when constraining an inherited component whose constraint is
7220 -- given by a discriminant of the parent.
7222 while Present
(D
) loop
7223 if D
= Entity
(Discrim
)
7224 or else Corresponding_Discriminant
(D
) = Entity
(Discrim
)
7229 Next_Discriminant
(D
);
7233 -- The corresponding_Discriminant mechanism is incomplete, because
7234 -- the correspondence between new and old discriminants is not one
7235 -- to one: one new discriminant can constrain several old ones.
7236 -- In that case, scan sequentially the stored_constraint, the list
7237 -- of discriminants of the parents, and the constraints.
7239 if Is_Derived_Type
(Typ
)
7240 and then Present
(Stored_Constraint
(Typ
))
7241 and then Scope
(Entity
(Discrim
)) = Etype
(Typ
)
7243 D
:= First_Discriminant
(Etype
(Typ
));
7244 E
:= First_Elmt
(Constraints
);
7245 G
:= First_Elmt
(Stored_Constraint
(Typ
));
7247 while Present
(D
) loop
7248 if D
= Entity
(Discrim
) then
7252 Next_Discriminant
(D
);
7258 -- Something is wrong if we did not find the value
7260 raise Program_Error
;
7261 end Get_Discr_Value
;
7263 ---------------------
7264 -- Is_Discriminant --
7265 ---------------------
7267 function Is_Discriminant
(Expr
: Node_Id
) return Boolean is
7268 Discrim_Scope
: Entity_Id
;
7271 if Denotes_Discriminant
(Expr
) then
7272 Discrim_Scope
:= Scope
(Entity
(Expr
));
7274 -- Either we have a reference to one of Typ's discriminants,
7276 pragma Assert
(Discrim_Scope
= Typ
7278 -- or to the discriminants of the parent type, in the case
7279 -- of a derivation of a tagged type with variants.
7281 or else Discrim_Scope
= Etype
(Typ
)
7282 or else Full_View
(Discrim_Scope
) = Etype
(Typ
)
7284 -- or same as above for the case where the discriminants
7285 -- were declared in Typ's private view.
7287 or else (Is_Private_Type
(Discrim_Scope
)
7288 and then Chars
(Discrim_Scope
) = Chars
(Typ
))
7290 -- or else we are deriving from the full view and the
7291 -- discriminant is declared in the private entity.
7293 or else (Is_Private_Type
(Typ
)
7294 and then Chars
(Discrim_Scope
) = Chars
(Typ
))
7296 -- or we have a class-wide type, in which case make sure the
7297 -- discriminant found belongs to the root type.
7299 or else (Is_Class_Wide_Type
(Typ
)
7300 and then Etype
(Typ
) = Discrim_Scope
));
7305 -- In all other cases we have something wrong.
7308 end Is_Discriminant
;
7310 -- Start of processing for Constrain_Component_Type
7313 if Is_Array_Type
(Compon_Type
) then
7314 return Build_Constrained_Array_Type
(Compon_Type
);
7316 elsif Has_Discriminants
(Compon_Type
) then
7317 return Build_Constrained_Discriminated_Type
(Compon_Type
);
7319 elsif Is_Access_Type
(Compon_Type
) then
7320 return Build_Constrained_Access_Type
(Compon_Type
);
7324 end Constrain_Component_Type
;
7326 --------------------------
7327 -- Constrain_Concurrent --
7328 --------------------------
7330 -- For concurrent types, the associated record value type carries the same
7331 -- discriminants, so when we constrain a concurrent type, we must constrain
7332 -- the value type as well.
7334 procedure Constrain_Concurrent
7335 (Def_Id
: in out Entity_Id
;
7337 Related_Nod
: Node_Id
;
7338 Related_Id
: Entity_Id
;
7341 T_Ent
: Entity_Id
:= Entity
(Subtype_Mark
(SI
));
7345 if Ekind
(T_Ent
) in Access_Kind
then
7346 T_Ent
:= Designated_Type
(T_Ent
);
7349 T_Val
:= Corresponding_Record_Type
(T_Ent
);
7351 if Present
(T_Val
) then
7354 Def_Id
:= Create_Itype
(E_Void
, Related_Nod
, Related_Id
, Suffix
);
7357 Constrain_Discriminated_Type
(Def_Id
, SI
, Related_Nod
);
7359 Set_Depends_On_Private
(Def_Id
, Has_Private_Component
(Def_Id
));
7360 Set_Corresponding_Record_Type
(Def_Id
,
7361 Constrain_Corresponding_Record
7362 (Def_Id
, T_Val
, Related_Nod
, Related_Id
));
7365 -- If there is no associated record, expansion is disabled and this
7366 -- is a generic context. Create a subtype in any case, so that
7367 -- semantic analysis can proceed.
7370 Def_Id
:= Create_Itype
(E_Void
, Related_Nod
, Related_Id
, Suffix
);
7373 Constrain_Discriminated_Type
(Def_Id
, SI
, Related_Nod
);
7375 end Constrain_Concurrent
;
7377 ------------------------------------
7378 -- Constrain_Corresponding_Record --
7379 ------------------------------------
7381 function Constrain_Corresponding_Record
7382 (Prot_Subt
: Entity_Id
;
7383 Corr_Rec
: Entity_Id
;
7384 Related_Nod
: Node_Id
;
7385 Related_Id
: Entity_Id
) return Entity_Id
7387 T_Sub
: constant Entity_Id
7388 := Create_Itype
(E_Record_Subtype
, Related_Nod
, Related_Id
, 'V');
7391 Set_Etype
(T_Sub
, Corr_Rec
);
7392 Init_Size_Align
(T_Sub
);
7393 Set_Has_Discriminants
(T_Sub
, Has_Discriminants
(Prot_Subt
));
7394 Set_Is_Constrained
(T_Sub
, True);
7395 Set_First_Entity
(T_Sub
, First_Entity
(Corr_Rec
));
7396 Set_Last_Entity
(T_Sub
, Last_Entity
(Corr_Rec
));
7398 Conditional_Delay
(T_Sub
, Corr_Rec
);
7400 if Has_Discriminants
(Prot_Subt
) then -- False only if errors.
7401 Set_Discriminant_Constraint
(T_Sub
,
7402 Discriminant_Constraint
(Prot_Subt
));
7403 Set_Stored_Constraint_From_Discriminant_Constraint
(T_Sub
);
7404 Create_Constrained_Components
(T_Sub
, Related_Nod
, Corr_Rec
,
7405 Discriminant_Constraint
(T_Sub
));
7408 Set_Depends_On_Private
(T_Sub
, Has_Private_Component
(T_Sub
));
7411 end Constrain_Corresponding_Record
;
7413 -----------------------
7414 -- Constrain_Decimal --
7415 -----------------------
7417 procedure Constrain_Decimal
(Def_Id
: Node_Id
; S
: Node_Id
) is
7418 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7419 C
: constant Node_Id
:= Constraint
(S
);
7420 Loc
: constant Source_Ptr
:= Sloc
(C
);
7421 Range_Expr
: Node_Id
;
7422 Digits_Expr
: Node_Id
;
7427 Set_Ekind
(Def_Id
, E_Decimal_Fixed_Point_Subtype
);
7429 if Nkind
(C
) = N_Range_Constraint
then
7430 Range_Expr
:= Range_Expression
(C
);
7431 Digits_Val
:= Digits_Value
(T
);
7434 pragma Assert
(Nkind
(C
) = N_Digits_Constraint
);
7435 Digits_Expr
:= Digits_Expression
(C
);
7436 Analyze_And_Resolve
(Digits_Expr
, Any_Integer
);
7438 Check_Digits_Expression
(Digits_Expr
);
7439 Digits_Val
:= Expr_Value
(Digits_Expr
);
7441 if Digits_Val
> Digits_Value
(T
) then
7443 ("digits expression is incompatible with subtype", C
);
7444 Digits_Val
:= Digits_Value
(T
);
7447 if Present
(Range_Constraint
(C
)) then
7448 Range_Expr
:= Range_Expression
(Range_Constraint
(C
));
7450 Range_Expr
:= Empty
;
7454 Set_Etype
(Def_Id
, Base_Type
(T
));
7455 Set_Size_Info
(Def_Id
, (T
));
7456 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7457 Set_Delta_Value
(Def_Id
, Delta_Value
(T
));
7458 Set_Scale_Value
(Def_Id
, Scale_Value
(T
));
7459 Set_Small_Value
(Def_Id
, Small_Value
(T
));
7460 Set_Machine_Radix_10
(Def_Id
, Machine_Radix_10
(T
));
7461 Set_Digits_Value
(Def_Id
, Digits_Val
);
7463 -- Manufacture range from given digits value if no range present
7465 if No
(Range_Expr
) then
7466 Bound_Val
:= (Ureal_10
** Digits_Val
- Ureal_1
) * Small_Value
(T
);
7470 Convert_To
(T
, Make_Real_Literal
(Loc
, (-Bound_Val
))),
7472 Convert_To
(T
, Make_Real_Literal
(Loc
, Bound_Val
)));
7476 Set_Scalar_Range_For_Subtype
(Def_Id
, Range_Expr
, T
);
7477 Set_Discrete_RM_Size
(Def_Id
);
7479 -- Unconditionally delay the freeze, since we cannot set size
7480 -- information in all cases correctly until the freeze point.
7482 Set_Has_Delayed_Freeze
(Def_Id
);
7483 end Constrain_Decimal
;
7485 ----------------------------------
7486 -- Constrain_Discriminated_Type --
7487 ----------------------------------
7489 procedure Constrain_Discriminated_Type
7490 (Def_Id
: Entity_Id
;
7492 Related_Nod
: Node_Id
;
7493 For_Access
: Boolean := False)
7495 E
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7498 Elist
: Elist_Id
:= New_Elmt_List
;
7500 procedure Fixup_Bad_Constraint
;
7501 -- This is called after finding a bad constraint, and after having
7502 -- posted an appropriate error message. The mission is to leave the
7503 -- entity T in as reasonable state as possible!
7505 --------------------------
7506 -- Fixup_Bad_Constraint --
7507 --------------------------
7509 procedure Fixup_Bad_Constraint
is
7511 -- Set a reasonable Ekind for the entity. For an incomplete type,
7512 -- we can't do much, but for other types, we can set the proper
7513 -- corresponding subtype kind.
7515 if Ekind
(T
) = E_Incomplete_Type
then
7516 Set_Ekind
(Def_Id
, Ekind
(T
));
7518 Set_Ekind
(Def_Id
, Subtype_Kind
(Ekind
(T
)));
7521 Set_Etype
(Def_Id
, Any_Type
);
7522 Set_Error_Posted
(Def_Id
);
7523 end Fixup_Bad_Constraint
;
7525 -- Start of processing for Constrain_Discriminated_Type
7528 C
:= Constraint
(S
);
7530 -- A discriminant constraint is only allowed in a subtype indication,
7531 -- after a subtype mark. This subtype mark must denote either a type
7532 -- with discriminants, or an access type whose designated type is a
7533 -- type with discriminants. A discriminant constraint specifies the
7534 -- values of these discriminants (RM 3.7.2(5)).
7536 T
:= Base_Type
(Entity
(Subtype_Mark
(S
)));
7538 if Ekind
(T
) in Access_Kind
then
7539 T
:= Designated_Type
(T
);
7542 if not Has_Discriminants
(T
) then
7543 Error_Msg_N
("invalid constraint: type has no discriminant", C
);
7544 Fixup_Bad_Constraint
;
7547 elsif Is_Constrained
(E
)
7548 or else (Ekind
(E
) = E_Class_Wide_Subtype
7549 and then Present
(Discriminant_Constraint
(E
)))
7551 Error_Msg_N
("type is already constrained", Subtype_Mark
(S
));
7552 Fixup_Bad_Constraint
;
7556 -- T may be an unconstrained subtype (e.g. a generic actual).
7557 -- Constraint applies to the base type.
7561 Elist
:= Build_Discriminant_Constraints
(T
, S
);
7563 -- If the list returned was empty we had an error in building the
7564 -- discriminant constraint. We have also already signalled an error
7565 -- in the incomplete type case
7567 if Is_Empty_Elmt_List
(Elist
) then
7568 Fixup_Bad_Constraint
;
7572 Build_Discriminated_Subtype
(T
, Def_Id
, Elist
, Related_Nod
, For_Access
);
7573 end Constrain_Discriminated_Type
;
7575 ---------------------------
7576 -- Constrain_Enumeration --
7577 ---------------------------
7579 procedure Constrain_Enumeration
(Def_Id
: Node_Id
; S
: Node_Id
) is
7580 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7581 C
: constant Node_Id
:= Constraint
(S
);
7584 Set_Ekind
(Def_Id
, E_Enumeration_Subtype
);
7586 Set_First_Literal
(Def_Id
, First_Literal
(Base_Type
(T
)));
7588 Set_Etype
(Def_Id
, Base_Type
(T
));
7589 Set_Size_Info
(Def_Id
, (T
));
7590 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7591 Set_Is_Character_Type
(Def_Id
, Is_Character_Type
(T
));
7593 Set_Scalar_Range_For_Subtype
(Def_Id
, Range_Expression
(C
), T
);
7595 Set_Discrete_RM_Size
(Def_Id
);
7597 end Constrain_Enumeration
;
7599 ----------------------
7600 -- Constrain_Float --
7601 ----------------------
7603 procedure Constrain_Float
(Def_Id
: Node_Id
; S
: Node_Id
) is
7604 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7610 Set_Ekind
(Def_Id
, E_Floating_Point_Subtype
);
7612 Set_Etype
(Def_Id
, Base_Type
(T
));
7613 Set_Size_Info
(Def_Id
, (T
));
7614 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7616 -- Process the constraint
7618 C
:= Constraint
(S
);
7620 -- Digits constraint present
7622 if Nkind
(C
) = N_Digits_Constraint
then
7623 if Warn_On_Obsolescent_Feature
then
7625 ("subtype digits constraint is an " &
7626 "obsolescent feature ('R'M 'J.3(8))?", C
);
7629 D
:= Digits_Expression
(C
);
7630 Analyze_And_Resolve
(D
, Any_Integer
);
7631 Check_Digits_Expression
(D
);
7632 Set_Digits_Value
(Def_Id
, Expr_Value
(D
));
7634 -- Check that digits value is in range. Obviously we can do this
7635 -- at compile time, but it is strictly a runtime check, and of
7636 -- course there is an ACVC test that checks this!
7638 if Digits_Value
(Def_Id
) > Digits_Value
(T
) then
7639 Error_Msg_Uint_1
:= Digits_Value
(T
);
7640 Error_Msg_N
("?digits value is too large, maximum is ^", D
);
7642 Make_Raise_Constraint_Error
(Sloc
(D
),
7643 Reason
=> CE_Range_Check_Failed
);
7644 Insert_Action
(Declaration_Node
(Def_Id
), Rais
);
7647 C
:= Range_Constraint
(C
);
7649 -- No digits constraint present
7652 Set_Digits_Value
(Def_Id
, Digits_Value
(T
));
7655 -- Range constraint present
7657 if Nkind
(C
) = N_Range_Constraint
then
7658 Set_Scalar_Range_For_Subtype
(Def_Id
, Range_Expression
(C
), T
);
7660 -- No range constraint present
7663 pragma Assert
(No
(C
));
7664 Set_Scalar_Range
(Def_Id
, Scalar_Range
(T
));
7667 Set_Is_Constrained
(Def_Id
);
7668 end Constrain_Float
;
7670 ---------------------
7671 -- Constrain_Index --
7672 ---------------------
7674 procedure Constrain_Index
7677 Related_Nod
: Node_Id
;
7678 Related_Id
: Entity_Id
;
7683 R
: Node_Id
:= Empty
;
7684 Checks_Off
: Boolean := False;
7685 T
: constant Entity_Id
:= Etype
(Index
);
7688 if Nkind
(S
) = N_Range
7690 (Nkind
(S
) = N_Attribute_Reference
7691 and then Attribute_Name
(S
) = Name_Range
)
7693 -- A Range attribute will transformed into N_Range by Resolve.
7699 -- ??? Why on earth do we turn checks of in this very specific case ?
7701 -- From the revision history: (Constrain_Index): Call
7702 -- Process_Range_Expr_In_Decl with range checking off for range
7703 -- bounds that are attributes. This avoids some horrible
7704 -- constraint error checks.
7706 if Nkind
(R
) = N_Range
7707 and then Nkind
(Low_Bound
(R
)) = N_Attribute_Reference
7708 and then Nkind
(High_Bound
(R
)) = N_Attribute_Reference
7713 Process_Range_Expr_In_Decl
(R
, T
, Empty_List
, Checks_Off
);
7715 if not Error_Posted
(S
)
7717 (Nkind
(S
) /= N_Range
7718 or else not Covers
(T
, (Etype
(Low_Bound
(S
))))
7719 or else not Covers
(T
, (Etype
(High_Bound
(S
)))))
7721 if Base_Type
(T
) /= Any_Type
7722 and then Etype
(Low_Bound
(S
)) /= Any_Type
7723 and then Etype
(High_Bound
(S
)) /= Any_Type
7725 Error_Msg_N
("range expected", S
);
7729 elsif Nkind
(S
) = N_Subtype_Indication
then
7730 -- the parser has verified that this is a discrete indication.
7732 Resolve_Discrete_Subtype_Indication
(S
, T
);
7733 R
:= Range_Expression
(Constraint
(S
));
7735 elsif Nkind
(S
) = N_Discriminant_Association
then
7737 -- syntactically valid in subtype indication.
7739 Error_Msg_N
("invalid index constraint", S
);
7740 Rewrite
(S
, New_Occurrence_Of
(T
, Sloc
(S
)));
7743 -- Subtype_Mark case, no anonymous subtypes to construct
7748 if Is_Entity_Name
(S
) then
7750 if not Is_Type
(Entity
(S
)) then
7751 Error_Msg_N
("expect subtype mark for index constraint", S
);
7753 elsif Base_Type
(Entity
(S
)) /= Base_Type
(T
) then
7754 Wrong_Type
(S
, Base_Type
(T
));
7760 Error_Msg_N
("invalid index constraint", S
);
7761 Rewrite
(S
, New_Occurrence_Of
(T
, Sloc
(S
)));
7767 Create_Itype
(E_Void
, Related_Nod
, Related_Id
, Suffix
, Suffix_Index
);
7769 Set_Etype
(Def_Id
, Base_Type
(T
));
7771 if Is_Modular_Integer_Type
(T
) then
7772 Set_Ekind
(Def_Id
, E_Modular_Integer_Subtype
);
7774 elsif Is_Integer_Type
(T
) then
7775 Set_Ekind
(Def_Id
, E_Signed_Integer_Subtype
);
7778 Set_Ekind
(Def_Id
, E_Enumeration_Subtype
);
7779 Set_Is_Character_Type
(Def_Id
, Is_Character_Type
(T
));
7782 Set_Size_Info
(Def_Id
, (T
));
7783 Set_RM_Size
(Def_Id
, RM_Size
(T
));
7784 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7786 Set_Scalar_Range
(Def_Id
, R
);
7788 Set_Etype
(S
, Def_Id
);
7789 Set_Discrete_RM_Size
(Def_Id
);
7790 end Constrain_Index
;
7792 -----------------------
7793 -- Constrain_Integer --
7794 -----------------------
7796 procedure Constrain_Integer
(Def_Id
: Node_Id
; S
: Node_Id
) is
7797 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7798 C
: constant Node_Id
:= Constraint
(S
);
7801 Set_Scalar_Range_For_Subtype
(Def_Id
, Range_Expression
(C
), T
);
7803 if Is_Modular_Integer_Type
(T
) then
7804 Set_Ekind
(Def_Id
, E_Modular_Integer_Subtype
);
7806 Set_Ekind
(Def_Id
, E_Signed_Integer_Subtype
);
7809 Set_Etype
(Def_Id
, Base_Type
(T
));
7810 Set_Size_Info
(Def_Id
, (T
));
7811 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7812 Set_Discrete_RM_Size
(Def_Id
);
7814 end Constrain_Integer
;
7816 ------------------------------
7817 -- Constrain_Ordinary_Fixed --
7818 ------------------------------
7820 procedure Constrain_Ordinary_Fixed
(Def_Id
: Node_Id
; S
: Node_Id
) is
7821 T
: constant Entity_Id
:= Entity
(Subtype_Mark
(S
));
7827 Set_Ekind
(Def_Id
, E_Ordinary_Fixed_Point_Subtype
);
7828 Set_Etype
(Def_Id
, Base_Type
(T
));
7829 Set_Size_Info
(Def_Id
, (T
));
7830 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
7831 Set_Small_Value
(Def_Id
, Small_Value
(T
));
7833 -- Process the constraint
7835 C
:= Constraint
(S
);
7837 -- Delta constraint present
7839 if Nkind
(C
) = N_Delta_Constraint
then
7840 if Warn_On_Obsolescent_Feature
then
7842 ("subtype delta constraint is an " &
7843 "obsolescent feature ('R'M 'J.3(7))?");
7846 D
:= Delta_Expression
(C
);
7847 Analyze_And_Resolve
(D
, Any_Real
);
7848 Check_Delta_Expression
(D
);
7849 Set_Delta_Value
(Def_Id
, Expr_Value_R
(D
));
7851 -- Check that delta value is in range. Obviously we can do this
7852 -- at compile time, but it is strictly a runtime check, and of
7853 -- course there is an ACVC test that checks this!
7855 if Delta_Value
(Def_Id
) < Delta_Value
(T
) then
7856 Error_Msg_N
("?delta value is too small", D
);
7858 Make_Raise_Constraint_Error
(Sloc
(D
),
7859 Reason
=> CE_Range_Check_Failed
);
7860 Insert_Action
(Declaration_Node
(Def_Id
), Rais
);
7863 C
:= Range_Constraint
(C
);
7865 -- No delta constraint present
7868 Set_Delta_Value
(Def_Id
, Delta_Value
(T
));
7871 -- Range constraint present
7873 if Nkind
(C
) = N_Range_Constraint
then
7874 Set_Scalar_Range_For_Subtype
(Def_Id
, Range_Expression
(C
), T
);
7876 -- No range constraint present
7879 pragma Assert
(No
(C
));
7880 Set_Scalar_Range
(Def_Id
, Scalar_Range
(T
));
7884 Set_Discrete_RM_Size
(Def_Id
);
7886 -- Unconditionally delay the freeze, since we cannot set size
7887 -- information in all cases correctly until the freeze point.
7889 Set_Has_Delayed_Freeze
(Def_Id
);
7890 end Constrain_Ordinary_Fixed
;
7892 ---------------------------
7893 -- Convert_Scalar_Bounds --
7894 ---------------------------
7896 procedure Convert_Scalar_Bounds
7898 Parent_Type
: Entity_Id
;
7899 Derived_Type
: Entity_Id
;
7902 Implicit_Base
: constant Entity_Id
:= Base_Type
(Derived_Type
);
7909 Lo
:= Build_Scalar_Bound
7910 (Type_Low_Bound
(Derived_Type
),
7911 Parent_Type
, Implicit_Base
);
7913 Hi
:= Build_Scalar_Bound
7914 (Type_High_Bound
(Derived_Type
),
7915 Parent_Type
, Implicit_Base
);
7922 Set_Includes_Infinities
(Rng
, Has_Infinities
(Derived_Type
));
7924 Set_Parent
(Rng
, N
);
7925 Set_Scalar_Range
(Derived_Type
, Rng
);
7927 -- Analyze the bounds
7929 Analyze_And_Resolve
(Lo
, Implicit_Base
);
7930 Analyze_And_Resolve
(Hi
, Implicit_Base
);
7932 -- Analyze the range itself, except that we do not analyze it if
7933 -- the bounds are real literals, and we have a fixed-point type.
7934 -- The reason for this is that we delay setting the bounds in this
7935 -- case till we know the final Small and Size values (see circuit
7936 -- in Freeze.Freeze_Fixed_Point_Type for further details).
7938 if Is_Fixed_Point_Type
(Parent_Type
)
7939 and then Nkind
(Lo
) = N_Real_Literal
7940 and then Nkind
(Hi
) = N_Real_Literal
7944 -- Here we do the analysis of the range.
7946 -- Note: we do this manually, since if we do a normal Analyze and
7947 -- Resolve call, there are problems with the conversions used for
7948 -- the derived type range.
7951 Set_Etype
(Rng
, Implicit_Base
);
7952 Set_Analyzed
(Rng
, True);
7954 end Convert_Scalar_Bounds
;
7960 procedure Copy_And_Swap
(Priv
, Full
: Entity_Id
) is
7963 -- Initialize new full declaration entity by copying the pertinent
7964 -- fields of the corresponding private declaration entity.
7966 -- We temporarily set Ekind to a value appropriate for a type to
7967 -- avoid assert failures in Einfo from checking for setting type
7968 -- attributes on something that is not a type. Ekind (Priv) is an
7969 -- appropriate choice, since it allowed the attributes to be set
7970 -- in the first place. This Ekind value will be modified later.
7972 Set_Ekind
(Full
, Ekind
(Priv
));
7974 -- Also set Etype temporarily to Any_Type, again, in the absence
7975 -- of errors, it will be properly reset, and if there are errors,
7976 -- then we want a value of Any_Type to remain.
7978 Set_Etype
(Full
, Any_Type
);
7980 -- Now start copying attributes
7982 Set_Has_Discriminants
(Full
, Has_Discriminants
(Priv
));
7984 if Has_Discriminants
(Full
) then
7985 Set_Discriminant_Constraint
(Full
, Discriminant_Constraint
(Priv
));
7986 Set_Stored_Constraint
(Full
, Stored_Constraint
(Priv
));
7989 Set_First_Rep_Item
(Full
, First_Rep_Item
(Priv
));
7990 Set_Homonym
(Full
, Homonym
(Priv
));
7991 Set_Is_Immediately_Visible
(Full
, Is_Immediately_Visible
(Priv
));
7992 Set_Is_Public
(Full
, Is_Public
(Priv
));
7993 Set_Is_Pure
(Full
, Is_Pure
(Priv
));
7994 Set_Is_Tagged_Type
(Full
, Is_Tagged_Type
(Priv
));
7996 Conditional_Delay
(Full
, Priv
);
7998 if Is_Tagged_Type
(Full
) then
7999 Set_Primitive_Operations
(Full
, Primitive_Operations
(Priv
));
8001 if Priv
= Base_Type
(Priv
) then
8002 Set_Class_Wide_Type
(Full
, Class_Wide_Type
(Priv
));
8006 Set_Is_Volatile
(Full
, Is_Volatile
(Priv
));
8007 Set_Treat_As_Volatile
(Full
, Treat_As_Volatile
(Priv
));
8008 Set_Scope
(Full
, Scope
(Priv
));
8009 Set_Next_Entity
(Full
, Next_Entity
(Priv
));
8010 Set_First_Entity
(Full
, First_Entity
(Priv
));
8011 Set_Last_Entity
(Full
, Last_Entity
(Priv
));
8013 -- If access types have been recorded for later handling, keep them
8014 -- in the full view so that they get handled when the full view
8015 -- freeze node is expanded.
8017 if Present
(Freeze_Node
(Priv
))
8018 and then Present
(Access_Types_To_Process
(Freeze_Node
(Priv
)))
8020 Ensure_Freeze_Node
(Full
);
8021 Set_Access_Types_To_Process
8022 (Freeze_Node
(Full
),
8023 Access_Types_To_Process
(Freeze_Node
(Priv
)));
8026 -- Swap the two entities. Now Privat is the full type entity and
8027 -- Full is the private one. They will be swapped back at the end
8028 -- of the private part. This swapping ensures that the entity that
8029 -- is visible in the private part is the full declaration.
8031 Exchange_Entities
(Priv
, Full
);
8032 Append_Entity
(Full
, Scope
(Full
));
8035 -------------------------------------
8036 -- Copy_Array_Base_Type_Attributes --
8037 -------------------------------------
8039 procedure Copy_Array_Base_Type_Attributes
(T1
, T2
: Entity_Id
) is
8041 Set_Component_Alignment
(T1
, Component_Alignment
(T2
));
8042 Set_Component_Type
(T1
, Component_Type
(T2
));
8043 Set_Component_Size
(T1
, Component_Size
(T2
));
8044 Set_Has_Controlled_Component
(T1
, Has_Controlled_Component
(T2
));
8045 Set_Finalize_Storage_Only
(T1
, Finalize_Storage_Only
(T2
));
8046 Set_Has_Non_Standard_Rep
(T1
, Has_Non_Standard_Rep
(T2
));
8047 Set_Has_Task
(T1
, Has_Task
(T2
));
8048 Set_Is_Packed
(T1
, Is_Packed
(T2
));
8049 Set_Has_Aliased_Components
(T1
, Has_Aliased_Components
(T2
));
8050 Set_Has_Atomic_Components
(T1
, Has_Atomic_Components
(T2
));
8051 Set_Has_Volatile_Components
(T1
, Has_Volatile_Components
(T2
));
8052 end Copy_Array_Base_Type_Attributes
;
8054 -----------------------------------
8055 -- Copy_Array_Subtype_Attributes --
8056 -----------------------------------
8058 procedure Copy_Array_Subtype_Attributes
(T1
, T2
: Entity_Id
) is
8060 Set_Size_Info
(T1
, T2
);
8062 Set_First_Index
(T1
, First_Index
(T2
));
8063 Set_Is_Aliased
(T1
, Is_Aliased
(T2
));
8064 Set_Is_Atomic
(T1
, Is_Atomic
(T2
));
8065 Set_Is_Volatile
(T1
, Is_Volatile
(T2
));
8066 Set_Treat_As_Volatile
(T1
, Treat_As_Volatile
(T2
));
8067 Set_Is_Constrained
(T1
, Is_Constrained
(T2
));
8068 Set_Depends_On_Private
(T1
, Has_Private_Component
(T2
));
8069 Set_First_Rep_Item
(T1
, First_Rep_Item
(T2
));
8070 Set_Convention
(T1
, Convention
(T2
));
8071 Set_Is_Limited_Composite
(T1
, Is_Limited_Composite
(T2
));
8072 Set_Is_Private_Composite
(T1
, Is_Private_Composite
(T2
));
8073 end Copy_Array_Subtype_Attributes
;
8075 -----------------------------------
8076 -- Create_Constrained_Components --
8077 -----------------------------------
8079 procedure Create_Constrained_Components
8081 Decl_Node
: Node_Id
;
8083 Constraints
: Elist_Id
)
8085 Loc
: constant Source_Ptr
:= Sloc
(Subt
);
8086 Comp_List
: constant Elist_Id
:= New_Elmt_List
;
8087 Parent_Type
: constant Entity_Id
:= Etype
(Typ
);
8088 Assoc_List
: constant List_Id
:= New_List
;
8089 Discr_Val
: Elmt_Id
;
8093 Is_Static
: Boolean := True;
8095 procedure Collect_Fixed_Components
(Typ
: Entity_Id
);
8096 -- Collect components of parent type that do not appear in a variant
8099 procedure Create_All_Components
;
8100 -- Iterate over Comp_List to create the components of the subtype.
8102 function Create_Component
(Old_Compon
: Entity_Id
) return Entity_Id
;
8103 -- Creates a new component from Old_Compon, copying all the fields from
8104 -- it, including its Etype, inserts the new component in the Subt entity
8105 -- chain and returns the new component.
8107 function Is_Variant_Record
(T
: Entity_Id
) return Boolean;
8108 -- If true, and discriminants are static, collect only components from
8109 -- variants selected by discriminant values.
8111 ------------------------------
8112 -- Collect_Fixed_Components --
8113 ------------------------------
8115 procedure Collect_Fixed_Components
(Typ
: Entity_Id
) is
8117 -- Build association list for discriminants, and find components of
8118 -- the variant part selected by the values of the discriminants.
8120 Old_C
:= First_Discriminant
(Typ
);
8121 Discr_Val
:= First_Elmt
(Constraints
);
8123 while Present
(Old_C
) loop
8124 Append_To
(Assoc_List
,
8125 Make_Component_Association
(Loc
,
8126 Choices
=> New_List
(New_Occurrence_Of
(Old_C
, Loc
)),
8127 Expression
=> New_Copy
(Node
(Discr_Val
))));
8129 Next_Elmt
(Discr_Val
);
8130 Next_Discriminant
(Old_C
);
8133 -- The tag, and the possible parent and controller components
8134 -- are unconditionally in the subtype.
8136 if Is_Tagged_Type
(Typ
)
8137 or else Has_Controlled_Component
(Typ
)
8139 Old_C
:= First_Component
(Typ
);
8141 while Present
(Old_C
) loop
8142 if Chars
((Old_C
)) = Name_uTag
8143 or else Chars
((Old_C
)) = Name_uParent
8144 or else Chars
((Old_C
)) = Name_uController
8146 Append_Elmt
(Old_C
, Comp_List
);
8149 Next_Component
(Old_C
);
8152 end Collect_Fixed_Components
;
8154 ---------------------------
8155 -- Create_All_Components --
8156 ---------------------------
8158 procedure Create_All_Components
is
8162 Comp
:= First_Elmt
(Comp_List
);
8164 while Present
(Comp
) loop
8165 Old_C
:= Node
(Comp
);
8166 New_C
:= Create_Component
(Old_C
);
8170 Constrain_Component_Type
8171 (Etype
(Old_C
), Subt
, Decl_Node
, Typ
, Constraints
));
8172 Set_Is_Public
(New_C
, Is_Public
(Subt
));
8176 end Create_All_Components
;
8178 ----------------------
8179 -- Create_Component --
8180 ----------------------
8182 function Create_Component
(Old_Compon
: Entity_Id
) return Entity_Id
is
8183 New_Compon
: constant Entity_Id
:= New_Copy
(Old_Compon
);
8186 -- Set the parent so we have a proper link for freezing etc. This
8187 -- is not a real parent pointer, since of course our parent does
8188 -- not own up to us and reference us, we are an illegitimate
8189 -- child of the original parent!
8191 Set_Parent
(New_Compon
, Parent
(Old_Compon
));
8193 -- We do not want this node marked as Comes_From_Source, since
8194 -- otherwise it would get first class status and a separate
8195 -- cross-reference line would be generated. Illegitimate
8196 -- children do not rate such recognition.
8198 Set_Comes_From_Source
(New_Compon
, False);
8200 -- But it is a real entity, and a birth certificate must be
8201 -- properly registered by entering it into the entity list.
8203 Enter_Name
(New_Compon
);
8205 end Create_Component
;
8207 -----------------------
8208 -- Is_Variant_Record --
8209 -----------------------
8211 function Is_Variant_Record
(T
: Entity_Id
) return Boolean is
8213 return Nkind
(Parent
(T
)) = N_Full_Type_Declaration
8214 and then Nkind
(Type_Definition
(Parent
(T
))) = N_Record_Definition
8215 and then Present
(Component_List
(Type_Definition
(Parent
(T
))))
8217 Variant_Part
(Component_List
(Type_Definition
(Parent
(T
)))));
8218 end Is_Variant_Record
;
8220 -- Start of processing for Create_Constrained_Components
8223 pragma Assert
(Subt
/= Base_Type
(Subt
));
8224 pragma Assert
(Typ
= Base_Type
(Typ
));
8226 Set_First_Entity
(Subt
, Empty
);
8227 Set_Last_Entity
(Subt
, Empty
);
8229 -- Check whether constraint is fully static, in which case we can
8230 -- optimize the list of components.
8232 Discr_Val
:= First_Elmt
(Constraints
);
8234 while Present
(Discr_Val
) loop
8236 if not Is_OK_Static_Expression
(Node
(Discr_Val
)) then
8241 Next_Elmt
(Discr_Val
);
8246 -- Inherit the discriminants of the parent type.
8248 Old_C
:= First_Discriminant
(Typ
);
8250 while Present
(Old_C
) loop
8251 New_C
:= Create_Component
(Old_C
);
8252 Set_Is_Public
(New_C
, Is_Public
(Subt
));
8253 Next_Discriminant
(Old_C
);
8257 and then Is_Variant_Record
(Typ
)
8259 Collect_Fixed_Components
(Typ
);
8263 Component_List
(Type_Definition
(Parent
(Typ
))),
8264 Governed_By
=> Assoc_List
,
8266 Report_Errors
=> Errors
);
8267 pragma Assert
(not Errors
);
8269 Create_All_Components
;
8271 -- If the subtype declaration is created for a tagged type derivation
8272 -- with constraints, we retrieve the record definition of the parent
8273 -- type to select the components of the proper variant.
8276 and then Is_Tagged_Type
(Typ
)
8277 and then Nkind
(Parent
(Typ
)) = N_Full_Type_Declaration
8279 Nkind
(Type_Definition
(Parent
(Typ
))) = N_Derived_Type_Definition
8280 and then Is_Variant_Record
(Parent_Type
)
8282 Collect_Fixed_Components
(Typ
);
8286 Component_List
(Type_Definition
(Parent
(Parent_Type
))),
8287 Governed_By
=> Assoc_List
,
8289 Report_Errors
=> Errors
);
8290 pragma Assert
(not Errors
);
8292 -- If the tagged derivation has a type extension, collect all the
8293 -- new components therein.
8296 Record_Extension_Part
(Type_Definition
(Parent
(Typ
))))
8298 Old_C
:= First_Component
(Typ
);
8300 while Present
(Old_C
) loop
8301 if Original_Record_Component
(Old_C
) = Old_C
8302 and then Chars
(Old_C
) /= Name_uTag
8303 and then Chars
(Old_C
) /= Name_uParent
8304 and then Chars
(Old_C
) /= Name_uController
8306 Append_Elmt
(Old_C
, Comp_List
);
8309 Next_Component
(Old_C
);
8313 Create_All_Components
;
8316 -- If the discriminants are not static, or if this is a multi-level
8317 -- type extension, we have to include all the components of the
8320 Old_C
:= First_Component
(Typ
);
8322 while Present
(Old_C
) loop
8323 New_C
:= Create_Component
(Old_C
);
8327 Constrain_Component_Type
8328 (Etype
(Old_C
), Subt
, Decl_Node
, Typ
, Constraints
));
8329 Set_Is_Public
(New_C
, Is_Public
(Subt
));
8331 Next_Component
(Old_C
);
8336 end Create_Constrained_Components
;
8338 ------------------------------------------
8339 -- Decimal_Fixed_Point_Type_Declaration --
8340 ------------------------------------------
8342 procedure Decimal_Fixed_Point_Type_Declaration
8346 Loc
: constant Source_Ptr
:= Sloc
(Def
);
8347 Digs_Expr
: constant Node_Id
:= Digits_Expression
(Def
);
8348 Delta_Expr
: constant Node_Id
:= Delta_Expression
(Def
);
8349 Implicit_Base
: Entity_Id
;
8355 -- Start of processing for Decimal_Fixed_Point_Type_Declaration
8358 Check_Restriction
(No_Fixed_Point
, Def
);
8360 -- Create implicit base type
8363 Create_Itype
(E_Decimal_Fixed_Point_Type
, Parent
(Def
), T
, 'B');
8364 Set_Etype
(Implicit_Base
, Implicit_Base
);
8366 -- Analyze and process delta expression
8368 Analyze_And_Resolve
(Delta_Expr
, Universal_Real
);
8370 Check_Delta_Expression
(Delta_Expr
);
8371 Delta_Val
:= Expr_Value_R
(Delta_Expr
);
8373 -- Check delta is power of 10, and determine scale value from it
8376 Val
: Ureal
:= Delta_Val
;
8379 Scale_Val
:= Uint_0
;
8381 if Val
< Ureal_1
then
8382 while Val
< Ureal_1
loop
8383 Val
:= Val
* Ureal_10
;
8384 Scale_Val
:= Scale_Val
+ 1;
8387 if Scale_Val
> 18 then
8388 Error_Msg_N
("scale exceeds maximum value of 18", Def
);
8389 Scale_Val
:= UI_From_Int
(+18);
8393 while Val
> Ureal_1
loop
8394 Val
:= Val
/ Ureal_10
;
8395 Scale_Val
:= Scale_Val
- 1;
8398 if Scale_Val
< -18 then
8399 Error_Msg_N
("scale is less than minimum value of -18", Def
);
8400 Scale_Val
:= UI_From_Int
(-18);
8404 if Val
/= Ureal_1
then
8405 Error_Msg_N
("delta expression must be a power of 10", Def
);
8406 Delta_Val
:= Ureal_10
** (-Scale_Val
);
8410 -- Set delta, scale and small (small = delta for decimal type)
8412 Set_Delta_Value
(Implicit_Base
, Delta_Val
);
8413 Set_Scale_Value
(Implicit_Base
, Scale_Val
);
8414 Set_Small_Value
(Implicit_Base
, Delta_Val
);
8416 -- Analyze and process digits expression
8418 Analyze_And_Resolve
(Digs_Expr
, Any_Integer
);
8419 Check_Digits_Expression
(Digs_Expr
);
8420 Digs_Val
:= Expr_Value
(Digs_Expr
);
8422 if Digs_Val
> 18 then
8423 Digs_Val
:= UI_From_Int
(+18);
8424 Error_Msg_N
("digits value out of range, maximum is 18", Digs_Expr
);
8427 Set_Digits_Value
(Implicit_Base
, Digs_Val
);
8428 Bound_Val
:= UR_From_Uint
(10 ** Digs_Val
- 1) * Delta_Val
;
8430 -- Set range of base type from digits value for now. This will be
8431 -- expanded to represent the true underlying base range by Freeze.
8433 Set_Fixed_Range
(Implicit_Base
, Loc
, -Bound_Val
, Bound_Val
);
8435 -- Set size to zero for now, size will be set at freeze time. We have
8436 -- to do this for ordinary fixed-point, because the size depends on
8437 -- the specified small, and we might as well do the same for decimal
8440 Init_Size_Align
(Implicit_Base
);
8442 -- If there are bounds given in the declaration use them as the
8443 -- bounds of the first named subtype.
8445 if Present
(Real_Range_Specification
(Def
)) then
8447 RRS
: constant Node_Id
:= Real_Range_Specification
(Def
);
8448 Low
: constant Node_Id
:= Low_Bound
(RRS
);
8449 High
: constant Node_Id
:= High_Bound
(RRS
);
8454 Analyze_And_Resolve
(Low
, Any_Real
);
8455 Analyze_And_Resolve
(High
, Any_Real
);
8456 Check_Real_Bound
(Low
);
8457 Check_Real_Bound
(High
);
8458 Low_Val
:= Expr_Value_R
(Low
);
8459 High_Val
:= Expr_Value_R
(High
);
8461 if Low_Val
< (-Bound_Val
) then
8463 ("range low bound too small for digits value", Low
);
8464 Low_Val
:= -Bound_Val
;
8467 if High_Val
> Bound_Val
then
8469 ("range high bound too large for digits value", High
);
8470 High_Val
:= Bound_Val
;
8473 Set_Fixed_Range
(T
, Loc
, Low_Val
, High_Val
);
8476 -- If no explicit range, use range that corresponds to given
8477 -- digits value. This will end up as the final range for the
8481 Set_Fixed_Range
(T
, Loc
, -Bound_Val
, Bound_Val
);
8484 -- Complete entity for first subtype
8486 Set_Ekind
(T
, E_Decimal_Fixed_Point_Subtype
);
8487 Set_Etype
(T
, Implicit_Base
);
8488 Set_Size_Info
(T
, Implicit_Base
);
8489 Set_First_Rep_Item
(T
, First_Rep_Item
(Implicit_Base
));
8490 Set_Digits_Value
(T
, Digs_Val
);
8491 Set_Delta_Value
(T
, Delta_Val
);
8492 Set_Small_Value
(T
, Delta_Val
);
8493 Set_Scale_Value
(T
, Scale_Val
);
8494 Set_Is_Constrained
(T
);
8495 end Decimal_Fixed_Point_Type_Declaration
;
8497 -----------------------
8498 -- Derive_Subprogram --
8499 -----------------------
8501 procedure Derive_Subprogram
8502 (New_Subp
: in out Entity_Id
;
8503 Parent_Subp
: Entity_Id
;
8504 Derived_Type
: Entity_Id
;
8505 Parent_Type
: Entity_Id
;
8506 Actual_Subp
: Entity_Id
:= Empty
)
8509 New_Formal
: Entity_Id
;
8510 Same_Subt
: constant Boolean :=
8511 Is_Scalar_Type
(Parent_Type
)
8512 and then Subtypes_Statically_Compatible
(Parent_Type
, Derived_Type
);
8513 Visible_Subp
: Entity_Id
:= Parent_Subp
;
8515 function Is_Private_Overriding
return Boolean;
8516 -- If Subp is a private overriding of a visible operation, the in-
8517 -- herited operation derives from the overridden op (even though
8518 -- its body is the overriding one) and the inherited operation is
8519 -- visible now. See sem_disp to see the details of the handling of
8520 -- the overridden subprogram, which is removed from the list of
8521 -- primitive operations of the type. The overridden subprogram is
8522 -- saved locally in Visible_Subp, and used to diagnose abstract
8523 -- operations that need overriding in the derived type.
8525 procedure Replace_Type
(Id
, New_Id
: Entity_Id
);
8526 -- When the type is an anonymous access type, create a new access type
8527 -- designating the derived type.
8529 procedure Set_Derived_Name
;
8530 -- This procedure sets the appropriate Chars name for New_Subp. This
8531 -- is normally just a copy of the parent name. An exception arises for
8532 -- type support subprograms, where the name is changed to reflect the
8533 -- name of the derived type, e.g. if type foo is derived from type bar,
8534 -- then a procedure barDA is derived with a name fooDA.
8536 ---------------------------
8537 -- Is_Private_Overriding --
8538 ---------------------------
8540 function Is_Private_Overriding
return Boolean is
8544 Prev
:= Homonym
(Parent_Subp
);
8546 -- The visible operation that is overriden is a homonym of
8547 -- the parent subprogram. We scan the homonym chain to find
8548 -- the one whose alias is the subprogram we are deriving.
8550 while Present
(Prev
) loop
8551 if Is_Dispatching_Operation
(Parent_Subp
)
8552 and then Present
(Prev
)
8553 and then Ekind
(Prev
) = Ekind
(Parent_Subp
)
8554 and then Alias
(Prev
) = Parent_Subp
8555 and then Scope
(Parent_Subp
) = Scope
(Prev
)
8556 and then not Is_Hidden
(Prev
)
8558 Visible_Subp
:= Prev
;
8562 Prev
:= Homonym
(Prev
);
8566 end Is_Private_Overriding
;
8572 procedure Replace_Type
(Id
, New_Id
: Entity_Id
) is
8573 Acc_Type
: Entity_Id
;
8577 -- When the type is an anonymous access type, create a new access
8578 -- type designating the derived type. This itype must be elaborated
8579 -- at the point of the derivation, not on subsequent calls that may
8580 -- be out of the proper scope for Gigi, so we insert a reference to
8581 -- it after the derivation.
8583 if Ekind
(Etype
(Id
)) = E_Anonymous_Access_Type
then
8585 Desig_Typ
: Entity_Id
:= Designated_Type
(Etype
(Id
));
8588 if Ekind
(Desig_Typ
) = E_Record_Type_With_Private
8589 and then Present
(Full_View
(Desig_Typ
))
8590 and then not Is_Private_Type
(Parent_Type
)
8592 Desig_Typ
:= Full_View
(Desig_Typ
);
8595 if Base_Type
(Desig_Typ
) = Base_Type
(Parent_Type
) then
8596 Acc_Type
:= New_Copy
(Etype
(Id
));
8597 Set_Etype
(Acc_Type
, Acc_Type
);
8598 Set_Scope
(Acc_Type
, New_Subp
);
8600 -- Compute size of anonymous access type.
8602 if Is_Array_Type
(Desig_Typ
)
8603 and then not Is_Constrained
(Desig_Typ
)
8605 Init_Size
(Acc_Type
, 2 * System_Address_Size
);
8607 Init_Size
(Acc_Type
, System_Address_Size
);
8610 Init_Alignment
(Acc_Type
);
8612 Set_Directly_Designated_Type
(Acc_Type
, Derived_Type
);
8614 Set_Etype
(New_Id
, Acc_Type
);
8615 Set_Scope
(New_Id
, New_Subp
);
8617 -- Create a reference to it.
8619 IR
:= Make_Itype_Reference
(Sloc
(Parent
(Derived_Type
)));
8620 Set_Itype
(IR
, Acc_Type
);
8621 Insert_After
(Parent
(Derived_Type
), IR
);
8624 Set_Etype
(New_Id
, Etype
(Id
));
8627 elsif Base_Type
(Etype
(Id
)) = Base_Type
(Parent_Type
)
8629 (Ekind
(Etype
(Id
)) = E_Record_Type_With_Private
8630 and then Present
(Full_View
(Etype
(Id
)))
8631 and then Base_Type
(Full_View
(Etype
(Id
))) =
8632 Base_Type
(Parent_Type
))
8635 -- Constraint checks on formals are generated during expansion,
8636 -- based on the signature of the original subprogram. The bounds
8637 -- of the derived type are not relevant, and thus we can use
8638 -- the base type for the formals. However, the return type may be
8639 -- used in a context that requires that the proper static bounds
8640 -- be used (a case statement, for example) and for those cases
8641 -- we must use the derived type (first subtype), not its base.
8643 if Etype
(Id
) = Parent_Type
8646 Set_Etype
(New_Id
, Derived_Type
);
8648 Set_Etype
(New_Id
, Base_Type
(Derived_Type
));
8652 Set_Etype
(New_Id
, Etype
(Id
));
8656 ----------------------
8657 -- Set_Derived_Name --
8658 ----------------------
8660 procedure Set_Derived_Name
is
8661 Nm
: constant TSS_Name_Type
:= Get_TSS_Name
(Parent_Subp
);
8663 if Nm
= TSS_Null
then
8664 Set_Chars
(New_Subp
, Chars
(Parent_Subp
));
8666 Set_Chars
(New_Subp
, Make_TSS_Name
(Base_Type
(Derived_Type
), Nm
));
8668 end Set_Derived_Name
;
8670 -- Start of processing for Derive_Subprogram
8674 New_Entity
(Nkind
(Parent_Subp
), Sloc
(Derived_Type
));
8675 Set_Ekind
(New_Subp
, Ekind
(Parent_Subp
));
8677 -- Check whether the inherited subprogram is a private operation that
8678 -- should be inherited but not yet made visible. Such subprograms can
8679 -- become visible at a later point (e.g., the private part of a public
8680 -- child unit) via Declare_Inherited_Private_Subprograms. If the
8681 -- following predicate is true, then this is not such a private
8682 -- operation and the subprogram simply inherits the name of the parent
8683 -- subprogram. Note the special check for the names of controlled
8684 -- operations, which are currently exempted from being inherited with
8685 -- a hidden name because they must be findable for generation of
8686 -- implicit run-time calls.
8688 if not Is_Hidden
(Parent_Subp
)
8689 or else Is_Internal
(Parent_Subp
)
8690 or else Is_Private_Overriding
8691 or else Is_Internal_Name
(Chars
(Parent_Subp
))
8692 or else Chars
(Parent_Subp
) = Name_Initialize
8693 or else Chars
(Parent_Subp
) = Name_Adjust
8694 or else Chars
(Parent_Subp
) = Name_Finalize
8698 -- If parent is hidden, this can be a regular derivation if the
8699 -- parent is immediately visible in a non-instantiating context,
8700 -- or if we are in the private part of an instance. This test
8701 -- should still be refined ???
8703 -- The test for In_Instance_Not_Visible avoids inheriting the
8704 -- derived operation as a non-visible operation in cases where
8705 -- the parent subprogram might not be visible now, but was
8706 -- visible within the original generic, so it would be wrong
8707 -- to make the inherited subprogram non-visible now. (Not
8708 -- clear if this test is fully correct; are there any cases
8709 -- where we should declare the inherited operation as not
8710 -- visible to avoid it being overridden, e.g., when the
8711 -- parent type is a generic actual with private primitives ???)
8713 -- (they should be treated the same as other private inherited
8714 -- subprograms, but it's not clear how to do this cleanly). ???
8716 elsif (In_Open_Scopes
(Scope
(Base_Type
(Parent_Type
)))
8717 and then Is_Immediately_Visible
(Parent_Subp
)
8718 and then not In_Instance
)
8719 or else In_Instance_Not_Visible
8723 -- The type is inheriting a private operation, so enter
8724 -- it with a special name so it can't be overridden.
8727 Set_Chars
(New_Subp
, New_External_Name
(Chars
(Parent_Subp
), 'P'));
8730 Set_Parent
(New_Subp
, Parent
(Derived_Type
));
8731 Replace_Type
(Parent_Subp
, New_Subp
);
8732 Conditional_Delay
(New_Subp
, Parent_Subp
);
8734 Formal
:= First_Formal
(Parent_Subp
);
8735 while Present
(Formal
) loop
8736 New_Formal
:= New_Copy
(Formal
);
8738 -- Normally we do not go copying parents, but in the case of
8739 -- formals, we need to link up to the declaration (which is
8740 -- the parameter specification), and it is fine to link up to
8741 -- the original formal's parameter specification in this case.
8743 Set_Parent
(New_Formal
, Parent
(Formal
));
8745 Append_Entity
(New_Formal
, New_Subp
);
8747 Replace_Type
(Formal
, New_Formal
);
8748 Next_Formal
(Formal
);
8751 -- If this derivation corresponds to a tagged generic actual, then
8752 -- primitive operations rename those of the actual. Otherwise the
8753 -- primitive operations rename those of the parent type, If the
8754 -- parent renames an intrinsic operator, so does the new subprogram.
8755 -- We except concatenation, which is always properly typed, and does
8756 -- not get expanded as other intrinsic operations.
8758 if No
(Actual_Subp
) then
8759 if Is_Intrinsic_Subprogram
(Parent_Subp
) then
8760 Set_Is_Intrinsic_Subprogram
(New_Subp
);
8762 if Present
(Alias
(Parent_Subp
))
8763 and then Chars
(Parent_Subp
) /= Name_Op_Concat
8765 Set_Alias
(New_Subp
, Alias
(Parent_Subp
));
8767 Set_Alias
(New_Subp
, Parent_Subp
);
8771 Set_Alias
(New_Subp
, Parent_Subp
);
8775 Set_Alias
(New_Subp
, Actual_Subp
);
8778 -- Derived subprograms of a tagged type must inherit the convention
8779 -- of the parent subprogram (a requirement of AI-117). Derived
8780 -- subprograms of untagged types simply get convention Ada by default.
8782 if Is_Tagged_Type
(Derived_Type
) then
8783 Set_Convention
(New_Subp
, Convention
(Parent_Subp
));
8786 Set_Is_Imported
(New_Subp
, Is_Imported
(Parent_Subp
));
8787 Set_Is_Exported
(New_Subp
, Is_Exported
(Parent_Subp
));
8789 if Ekind
(Parent_Subp
) = E_Procedure
then
8790 Set_Is_Valued_Procedure
8791 (New_Subp
, Is_Valued_Procedure
(Parent_Subp
));
8794 -- A derived function with a controlling result is abstract.
8795 -- If the Derived_Type is a nonabstract formal generic derived
8796 -- type, then inherited operations are not abstract: check is
8797 -- done at instantiation time. If the derivation is for a generic
8798 -- actual, the function is not abstract unless the actual is.
8800 if Is_Generic_Type
(Derived_Type
)
8801 and then not Is_Abstract
(Derived_Type
)
8805 elsif Is_Abstract
(Alias
(New_Subp
))
8806 or else (Is_Tagged_Type
(Derived_Type
)
8807 and then Etype
(New_Subp
) = Derived_Type
8808 and then No
(Actual_Subp
))
8810 Set_Is_Abstract
(New_Subp
);
8812 -- Finally, if the parent type is abstract we must verify that all
8813 -- inherited operations are either non-abstract or overridden, or
8814 -- that the derived type itself is abstract (this check is performed
8815 -- at the end of a package declaration, in Check_Abstract_Overriding).
8816 -- A private overriding in the parent type will not be visible in the
8817 -- derivation if we are not in an inner package or in a child unit of
8818 -- the parent type, in which case the abstractness of the inherited
8819 -- operation is carried to the new subprogram.
8821 elsif Is_Abstract
(Parent_Type
)
8822 and then not In_Open_Scopes
(Scope
(Parent_Type
))
8823 and then Is_Private_Overriding
8824 and then Is_Abstract
(Visible_Subp
)
8826 Set_Alias
(New_Subp
, Visible_Subp
);
8827 Set_Is_Abstract
(New_Subp
);
8830 New_Overloaded_Entity
(New_Subp
, Derived_Type
);
8832 -- Check for case of a derived subprogram for the instantiation
8833 -- of a formal derived tagged type, if so mark the subprogram as
8834 -- dispatching and inherit the dispatching attributes of the
8835 -- parent subprogram. The derived subprogram is effectively a
8836 -- renaming of the actual subprogram, so it needs to have the
8837 -- same attributes as the actual.
8839 if Present
(Actual_Subp
)
8840 and then Is_Dispatching_Operation
(Parent_Subp
)
8842 Set_Is_Dispatching_Operation
(New_Subp
);
8843 if Present
(DTC_Entity
(Parent_Subp
)) then
8844 Set_DTC_Entity
(New_Subp
, DTC_Entity
(Parent_Subp
));
8845 Set_DT_Position
(New_Subp
, DT_Position
(Parent_Subp
));
8849 -- Indicate that a derived subprogram does not require a body
8850 -- and that it does not require processing of default expressions.
8852 Set_Has_Completion
(New_Subp
);
8853 Set_Default_Expressions_Processed
(New_Subp
);
8855 if Ekind
(New_Subp
) = E_Function
then
8856 Set_Mechanism
(New_Subp
, Mechanism
(Parent_Subp
));
8858 end Derive_Subprogram
;
8860 ------------------------
8861 -- Derive_Subprograms --
8862 ------------------------
8864 procedure Derive_Subprograms
8865 (Parent_Type
: Entity_Id
;
8866 Derived_Type
: Entity_Id
;
8867 Generic_Actual
: Entity_Id
:= Empty
)
8869 Op_List
: constant Elist_Id
:=
8870 Collect_Primitive_Operations
(Parent_Type
);
8871 Act_List
: Elist_Id
;
8875 New_Subp
: Entity_Id
:= Empty
;
8876 Parent_Base
: Entity_Id
;
8879 if Ekind
(Parent_Type
) = E_Record_Type_With_Private
8880 and then Has_Discriminants
(Parent_Type
)
8881 and then Present
(Full_View
(Parent_Type
))
8883 Parent_Base
:= Full_View
(Parent_Type
);
8885 Parent_Base
:= Parent_Type
;
8888 Elmt
:= First_Elmt
(Op_List
);
8890 if Present
(Generic_Actual
) then
8891 Act_List
:= Collect_Primitive_Operations
(Generic_Actual
);
8892 Act_Elmt
:= First_Elmt
(Act_List
);
8894 Act_Elmt
:= No_Elmt
;
8897 -- Literals are derived earlier in the process of building the
8898 -- derived type, and are skipped here.
8900 while Present
(Elmt
) loop
8901 Subp
:= Node
(Elmt
);
8903 if Ekind
(Subp
) /= E_Enumeration_Literal
then
8904 if No
(Generic_Actual
) then
8906 (New_Subp
, Subp
, Derived_Type
, Parent_Base
);
8909 Derive_Subprogram
(New_Subp
, Subp
,
8910 Derived_Type
, Parent_Base
, Node
(Act_Elmt
));
8911 Next_Elmt
(Act_Elmt
);
8917 end Derive_Subprograms
;
8919 --------------------------------
8920 -- Derived_Standard_Character --
8921 --------------------------------
8923 procedure Derived_Standard_Character
8925 Parent_Type
: Entity_Id
;
8926 Derived_Type
: Entity_Id
)
8928 Loc
: constant Source_Ptr
:= Sloc
(N
);
8929 Def
: constant Node_Id
:= Type_Definition
(N
);
8930 Indic
: constant Node_Id
:= Subtype_Indication
(Def
);
8931 Parent_Base
: constant Entity_Id
:= Base_Type
(Parent_Type
);
8932 Implicit_Base
: constant Entity_Id
:=
8934 (E_Enumeration_Type
, N
, Derived_Type
, 'B');
8940 Discard_Node
(Process_Subtype
(Indic
, N
));
8942 Set_Etype
(Implicit_Base
, Parent_Base
);
8943 Set_Size_Info
(Implicit_Base
, Root_Type
(Parent_Type
));
8944 Set_RM_Size
(Implicit_Base
, RM_Size
(Root_Type
(Parent_Type
)));
8946 Set_Is_Character_Type
(Implicit_Base
, True);
8947 Set_Has_Delayed_Freeze
(Implicit_Base
);
8949 -- The bounds of the implicit base are the bounds of the parent base.
8950 -- Note that their type is the parent base.
8952 Lo
:= New_Copy_Tree
(Type_Low_Bound
(Parent_Base
));
8953 Hi
:= New_Copy_Tree
(Type_High_Bound
(Parent_Base
));
8955 Set_Scalar_Range
(Implicit_Base
,
8960 Conditional_Delay
(Derived_Type
, Parent_Type
);
8962 Set_Ekind
(Derived_Type
, E_Enumeration_Subtype
);
8963 Set_Etype
(Derived_Type
, Implicit_Base
);
8964 Set_Size_Info
(Derived_Type
, Parent_Type
);
8966 if Unknown_RM_Size
(Derived_Type
) then
8967 Set_RM_Size
(Derived_Type
, RM_Size
(Parent_Type
));
8970 Set_Is_Character_Type
(Derived_Type
, True);
8972 if Nkind
(Indic
) /= N_Subtype_Indication
then
8974 -- If no explicit constraint, the bounds are those
8975 -- of the parent type.
8977 Lo
:= New_Copy_Tree
(Type_Low_Bound
(Parent_Type
));
8978 Hi
:= New_Copy_Tree
(Type_High_Bound
(Parent_Type
));
8979 Set_Scalar_Range
(Derived_Type
, Make_Range
(Loc
, Lo
, Hi
));
8982 Convert_Scalar_Bounds
(N
, Parent_Type
, Derived_Type
, Loc
);
8984 -- Because the implicit base is used in the conversion of the bounds,
8985 -- we have to freeze it now. This is similar to what is done for
8986 -- numeric types, and it equally suspicious, but otherwise a non-
8987 -- static bound will have a reference to an unfrozen type, which is
8988 -- rejected by Gigi (???).
8990 Freeze_Before
(N
, Implicit_Base
);
8991 end Derived_Standard_Character
;
8993 ------------------------------
8994 -- Derived_Type_Declaration --
8995 ------------------------------
8997 procedure Derived_Type_Declaration
9000 Is_Completion
: Boolean)
9002 Def
: constant Node_Id
:= Type_Definition
(N
);
9003 Indic
: constant Node_Id
:= Subtype_Indication
(Def
);
9004 Extension
: constant Node_Id
:= Record_Extension_Part
(Def
);
9005 Parent_Type
: Entity_Id
;
9006 Parent_Scope
: Entity_Id
;
9010 Parent_Type
:= Find_Type_Of_Subtype_Indic
(Indic
);
9012 if Parent_Type
= Any_Type
9013 or else Etype
(Parent_Type
) = Any_Type
9014 or else (Is_Class_Wide_Type
(Parent_Type
)
9015 and then Etype
(Parent_Type
) = T
)
9017 -- If Parent_Type is undefined or illegal, make new type into
9018 -- a subtype of Any_Type, and set a few attributes to prevent
9019 -- cascaded errors. If this is a self-definition, emit error now.
9022 or else T
= Etype
(Parent_Type
)
9024 Error_Msg_N
("type cannot be used in its own definition", Indic
);
9027 Set_Ekind
(T
, Ekind
(Parent_Type
));
9028 Set_Etype
(T
, Any_Type
);
9029 Set_Scalar_Range
(T
, Scalar_Range
(Any_Type
));
9031 if Is_Tagged_Type
(T
) then
9032 Set_Primitive_Operations
(T
, New_Elmt_List
);
9037 elsif Is_Unchecked_Union
(Parent_Type
) then
9038 Error_Msg_N
("cannot derive from Unchecked_Union type", N
);
9041 -- Only composite types other than array types are allowed to have
9044 if Present
(Discriminant_Specifications
(N
))
9045 and then (Is_Elementary_Type
(Parent_Type
)
9046 or else Is_Array_Type
(Parent_Type
))
9047 and then not Error_Posted
(N
)
9050 ("elementary or array type cannot have discriminants",
9051 Defining_Identifier
(First
(Discriminant_Specifications
(N
))));
9052 Set_Has_Discriminants
(T
, False);
9055 -- In Ada 83, a derived type defined in a package specification cannot
9056 -- be used for further derivation until the end of its visible part.
9057 -- Note that derivation in the private part of the package is allowed.
9060 and then Is_Derived_Type
(Parent_Type
)
9061 and then In_Visible_Part
(Scope
(Parent_Type
))
9063 if Ada_83
and then Comes_From_Source
(Indic
) then
9065 ("(Ada 83): premature use of type for derivation", Indic
);
9069 -- Check for early use of incomplete or private type
9071 if Ekind
(Parent_Type
) = E_Void
9072 or else Ekind
(Parent_Type
) = E_Incomplete_Type
9074 Error_Msg_N
("premature derivation of incomplete type", Indic
);
9077 elsif (Is_Incomplete_Or_Private_Type
(Parent_Type
)
9078 and then not Is_Generic_Type
(Parent_Type
)
9079 and then not Is_Generic_Type
(Root_Type
(Parent_Type
))
9080 and then not Is_Generic_Actual_Type
(Parent_Type
))
9081 or else Has_Private_Component
(Parent_Type
)
9083 -- The ancestor type of a formal type can be incomplete, in which
9084 -- case only the operations of the partial view are available in
9085 -- the generic. Subsequent checks may be required when the full
9086 -- view is analyzed, to verify that derivation from a tagged type
9087 -- has an extension.
9089 if Nkind
(Original_Node
(N
)) = N_Formal_Type_Declaration
then
9092 elsif No
(Underlying_Type
(Parent_Type
))
9093 or else Has_Private_Component
(Parent_Type
)
9096 ("premature derivation of derived or private type", Indic
);
9098 -- Flag the type itself as being in error, this prevents some
9099 -- nasty problems with people looking at the malformed type.
9101 Set_Error_Posted
(T
);
9103 -- Check that within the immediate scope of an untagged partial
9104 -- view it's illegal to derive from the partial view if the
9105 -- full view is tagged. (7.3(7))
9107 -- We verify that the Parent_Type is a partial view by checking
9108 -- that it is not a Full_Type_Declaration (i.e. a private type or
9109 -- private extension declaration), to distinguish a partial view
9110 -- from a derivation from a private type which also appears as
9113 elsif Present
(Full_View
(Parent_Type
))
9114 and then Nkind
(Parent
(Parent_Type
)) /= N_Full_Type_Declaration
9115 and then not Is_Tagged_Type
(Parent_Type
)
9116 and then Is_Tagged_Type
(Full_View
(Parent_Type
))
9118 Parent_Scope
:= Scope
(T
);
9119 while Present
(Parent_Scope
)
9120 and then Parent_Scope
/= Standard_Standard
9122 if Parent_Scope
= Scope
(Parent_Type
) then
9124 ("premature derivation from type with tagged full view",
9128 Parent_Scope
:= Scope
(Parent_Scope
);
9133 -- Check that form of derivation is appropriate
9135 Taggd
:= Is_Tagged_Type
(Parent_Type
);
9137 -- Perhaps the parent type should be changed to the class-wide type's
9138 -- specific type in this case to prevent cascading errors ???
9140 if Present
(Extension
) and then Is_Class_Wide_Type
(Parent_Type
) then
9141 Error_Msg_N
("parent type must not be a class-wide type", Indic
);
9145 if Present
(Extension
) and then not Taggd
then
9147 ("type derived from untagged type cannot have extension", Indic
);
9149 elsif No
(Extension
) and then Taggd
then
9150 -- If this is within a private part (or body) of a generic
9151 -- instantiation then the derivation is allowed (the parent
9152 -- type can only appear tagged in this case if it's a generic
9153 -- actual type, since it would otherwise have been rejected
9154 -- in the analysis of the generic template).
9156 if not Is_Generic_Actual_Type
(Parent_Type
)
9157 or else In_Visible_Part
(Scope
(Parent_Type
))
9160 ("type derived from tagged type must have extension", Indic
);
9164 Build_Derived_Type
(N
, Parent_Type
, T
, Is_Completion
);
9165 end Derived_Type_Declaration
;
9167 ----------------------------------
9168 -- Enumeration_Type_Declaration --
9169 ----------------------------------
9171 procedure Enumeration_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
) is
9178 -- Create identifier node representing lower bound
9180 B_Node
:= New_Node
(N_Identifier
, Sloc
(Def
));
9181 L
:= First
(Literals
(Def
));
9182 Set_Chars
(B_Node
, Chars
(L
));
9183 Set_Entity
(B_Node
, L
);
9184 Set_Etype
(B_Node
, T
);
9185 Set_Is_Static_Expression
(B_Node
, True);
9187 R_Node
:= New_Node
(N_Range
, Sloc
(Def
));
9188 Set_Low_Bound
(R_Node
, B_Node
);
9190 Set_Ekind
(T
, E_Enumeration_Type
);
9191 Set_First_Literal
(T
, L
);
9193 Set_Is_Constrained
(T
);
9197 -- Loop through literals of enumeration type setting pos and rep values
9198 -- except that if the Ekind is already set, then it means that the
9199 -- literal was already constructed (case of a derived type declaration
9200 -- and we should not disturb the Pos and Rep values.
9202 while Present
(L
) loop
9203 if Ekind
(L
) /= E_Enumeration_Literal
then
9204 Set_Ekind
(L
, E_Enumeration_Literal
);
9205 Set_Enumeration_Pos
(L
, Ev
);
9206 Set_Enumeration_Rep
(L
, Ev
);
9207 Set_Is_Known_Valid
(L
, True);
9211 New_Overloaded_Entity
(L
);
9212 Generate_Definition
(L
);
9213 Set_Convention
(L
, Convention_Intrinsic
);
9215 if Nkind
(L
) = N_Defining_Character_Literal
then
9216 Set_Is_Character_Type
(T
, True);
9223 -- Now create a node representing upper bound
9225 B_Node
:= New_Node
(N_Identifier
, Sloc
(Def
));
9226 Set_Chars
(B_Node
, Chars
(Last
(Literals
(Def
))));
9227 Set_Entity
(B_Node
, Last
(Literals
(Def
)));
9228 Set_Etype
(B_Node
, T
);
9229 Set_Is_Static_Expression
(B_Node
, True);
9231 Set_High_Bound
(R_Node
, B_Node
);
9232 Set_Scalar_Range
(T
, R_Node
);
9233 Set_RM_Size
(T
, UI_From_Int
(Minimum_Size
(T
)));
9236 -- Set Discard_Names if configuration pragma set, or if there is
9237 -- a parameterless pragma in the current declarative region
9239 if Global_Discard_Names
9240 or else Discard_Names
(Scope
(T
))
9242 Set_Discard_Names
(T
);
9245 -- Process end label if there is one
9247 if Present
(Def
) then
9248 Process_End_Label
(Def
, 'e', T
);
9250 end Enumeration_Type_Declaration
;
9252 ---------------------------------
9253 -- Expand_To_Stored_Constraint --
9254 ---------------------------------
9256 function Expand_To_Stored_Constraint
9258 Constraint
: Elist_Id
) return Elist_Id
9260 Explicitly_Discriminated_Type
: Entity_Id
;
9261 Expansion
: Elist_Id
;
9262 Discriminant
: Entity_Id
;
9264 function Type_With_Explicit_Discrims
(Id
: Entity_Id
) return Entity_Id
;
9265 -- Find the nearest type that actually specifies discriminants.
9267 ---------------------------------
9268 -- Type_With_Explicit_Discrims --
9269 ---------------------------------
9271 function Type_With_Explicit_Discrims
(Id
: Entity_Id
) return Entity_Id
is
9272 Typ
: constant E
:= Base_Type
(Id
);
9275 if Ekind
(Typ
) in Incomplete_Or_Private_Kind
then
9276 if Present
(Full_View
(Typ
)) then
9277 return Type_With_Explicit_Discrims
(Full_View
(Typ
));
9281 if Has_Discriminants
(Typ
) then
9286 if Etype
(Typ
) = Typ
then
9288 elsif Has_Discriminants
(Typ
) then
9291 return Type_With_Explicit_Discrims
(Etype
(Typ
));
9294 end Type_With_Explicit_Discrims
;
9296 -- Start of processing for Expand_To_Stored_Constraint
9300 or else Is_Empty_Elmt_List
(Constraint
)
9305 Explicitly_Discriminated_Type
:= Type_With_Explicit_Discrims
(Typ
);
9307 if No
(Explicitly_Discriminated_Type
) then
9311 Expansion
:= New_Elmt_List
;
9314 First_Stored_Discriminant
(Explicitly_Discriminated_Type
);
9316 while Present
(Discriminant
) loop
9319 Get_Discriminant_Value
(
9320 Discriminant
, Explicitly_Discriminated_Type
, Constraint
),
9323 Next_Stored_Discriminant
(Discriminant
);
9327 end Expand_To_Stored_Constraint
;
9329 --------------------
9330 -- Find_Type_Name --
9331 --------------------
9333 function Find_Type_Name
(N
: Node_Id
) return Entity_Id
is
9334 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
9340 -- Find incomplete declaration, if some was given.
9342 Prev
:= Current_Entity_In_Scope
(Id
);
9344 if Present
(Prev
) then
9346 -- Previous declaration exists. Error if not incomplete/private case
9347 -- except if previous declaration is implicit, etc. Enter_Name will
9348 -- emit error if appropriate.
9350 Prev_Par
:= Parent
(Prev
);
9352 if not Is_Incomplete_Or_Private_Type
(Prev
) then
9356 elsif Nkind
(N
) /= N_Full_Type_Declaration
9357 and then Nkind
(N
) /= N_Task_Type_Declaration
9358 and then Nkind
(N
) /= N_Protected_Type_Declaration
9360 -- Completion must be a full type declarations (RM 7.3(4))
9362 Error_Msg_Sloc
:= Sloc
(Prev
);
9363 Error_Msg_NE
("invalid completion of }", Id
, Prev
);
9365 -- Set scope of Id to avoid cascaded errors. Entity is never
9366 -- examined again, except when saving globals in generics.
9368 Set_Scope
(Id
, Current_Scope
);
9371 -- Case of full declaration of incomplete type
9373 elsif Ekind
(Prev
) = E_Incomplete_Type
then
9375 -- Indicate that the incomplete declaration has a matching
9376 -- full declaration. The defining occurrence of the incomplete
9377 -- declaration remains the visible one, and the procedure
9378 -- Get_Full_View dereferences it whenever the type is used.
9380 if Present
(Full_View
(Prev
)) then
9381 Error_Msg_NE
("invalid redeclaration of }", Id
, Prev
);
9384 Set_Full_View
(Prev
, Id
);
9385 Append_Entity
(Id
, Current_Scope
);
9386 Set_Is_Public
(Id
, Is_Public
(Prev
));
9387 Set_Is_Internal
(Id
);
9390 -- Case of full declaration of private type
9393 if Nkind
(Parent
(Prev
)) /= N_Private_Extension_Declaration
then
9394 if Etype
(Prev
) /= Prev
then
9396 -- Prev is a private subtype or a derived type, and needs
9399 Error_Msg_NE
("invalid redeclaration of }", Id
, Prev
);
9402 elsif Ekind
(Prev
) = E_Private_Type
9404 (Nkind
(N
) = N_Task_Type_Declaration
9405 or else Nkind
(N
) = N_Protected_Type_Declaration
)
9408 ("completion of nonlimited type cannot be limited", N
);
9411 elsif Nkind
(N
) /= N_Full_Type_Declaration
9412 or else Nkind
(Type_Definition
(N
)) /= N_Derived_Type_Definition
9414 Error_Msg_N
("full view of private extension must be"
9415 & " an extension", N
);
9417 elsif not (Abstract_Present
(Parent
(Prev
)))
9418 and then Abstract_Present
(Type_Definition
(N
))
9420 Error_Msg_N
("full view of non-abstract extension cannot"
9421 & " be abstract", N
);
9424 if not In_Private_Part
(Current_Scope
) then
9426 ("declaration of full view must appear in private part", N
);
9429 Copy_And_Swap
(Prev
, Id
);
9430 Set_Has_Private_Declaration
(Prev
);
9431 Set_Has_Private_Declaration
(Id
);
9433 -- If no error, propagate freeze_node from private to full view.
9434 -- It may have been generated for an early operational item.
9436 if Present
(Freeze_Node
(Id
))
9437 and then Serious_Errors_Detected
= 0
9438 and then No
(Full_View
(Id
))
9440 Set_Freeze_Node
(Prev
, Freeze_Node
(Id
));
9441 Set_Freeze_Node
(Id
, Empty
);
9442 Set_First_Rep_Item
(Prev
, First_Rep_Item
(Id
));
9445 Set_Full_View
(Id
, Prev
);
9449 -- Verify that full declaration conforms to incomplete one
9451 if Is_Incomplete_Or_Private_Type
(Prev
)
9452 and then Present
(Discriminant_Specifications
(Prev_Par
))
9454 if Present
(Discriminant_Specifications
(N
)) then
9455 if Ekind
(Prev
) = E_Incomplete_Type
then
9456 Check_Discriminant_Conformance
(N
, Prev
, Prev
);
9458 Check_Discriminant_Conformance
(N
, Prev
, Id
);
9463 ("missing discriminants in full type declaration", N
);
9465 -- To avoid cascaded errors on subsequent use, share the
9466 -- discriminants of the partial view.
9468 Set_Discriminant_Specifications
(N
,
9469 Discriminant_Specifications
(Prev_Par
));
9473 -- A prior untagged private type can have an associated
9474 -- class-wide type due to use of the class attribute,
9475 -- and in this case also the full type is required to
9479 and then (Is_Tagged_Type
(Prev
)
9480 or else Present
(Class_Wide_Type
(Prev
)))
9482 -- The full declaration is either a tagged record or an
9483 -- extension otherwise this is an error
9485 if Nkind
(Type_Definition
(N
)) = N_Record_Definition
then
9486 if not Tagged_Present
(Type_Definition
(N
)) then
9488 ("full declaration of } must be tagged", Prev
, Id
);
9489 Set_Is_Tagged_Type
(Id
);
9490 Set_Primitive_Operations
(Id
, New_Elmt_List
);
9493 elsif Nkind
(Type_Definition
(N
)) = N_Derived_Type_Definition
then
9494 if No
(Record_Extension_Part
(Type_Definition
(N
))) then
9496 "full declaration of } must be a record extension",
9498 Set_Is_Tagged_Type
(Id
);
9499 Set_Primitive_Operations
(Id
, New_Elmt_List
);
9504 ("full declaration of } must be a tagged type", Prev
, Id
);
9512 -- New type declaration
9519 -------------------------
9520 -- Find_Type_Of_Object --
9521 -------------------------
9523 function Find_Type_Of_Object
9525 Related_Nod
: Node_Id
) return Entity_Id
9527 Def_Kind
: constant Node_Kind
:= Nkind
(Obj_Def
);
9528 P
: constant Node_Id
:= Parent
(Obj_Def
);
9533 -- Case of an anonymous array subtype
9535 if Def_Kind
= N_Constrained_Array_Definition
9536 or else Def_Kind
= N_Unconstrained_Array_Definition
9539 Array_Type_Declaration
(T
, Obj_Def
);
9541 -- Create an explicit subtype whenever possible.
9543 elsif Nkind
(P
) /= N_Component_Declaration
9544 and then Def_Kind
= N_Subtype_Indication
9546 -- Base name of subtype on object name, which will be unique in
9547 -- the current scope.
9549 -- If this is a duplicate declaration, return base type, to avoid
9550 -- generating duplicate anonymous types.
9552 if Error_Posted
(P
) then
9553 Analyze
(Subtype_Mark
(Obj_Def
));
9554 return Entity
(Subtype_Mark
(Obj_Def
));
9559 (Chars
(Defining_Identifier
(Related_Nod
)), 'S', 0, 'T');
9561 T
:= Make_Defining_Identifier
(Sloc
(P
), Nam
);
9563 Insert_Action
(Obj_Def
,
9564 Make_Subtype_Declaration
(Sloc
(P
),
9565 Defining_Identifier
=> T
,
9566 Subtype_Indication
=> Relocate_Node
(Obj_Def
)));
9568 -- This subtype may need freezing and it will not be done
9569 -- automatically if the object declaration is not in a
9570 -- declarative part. Since this is an object declaration, the
9571 -- type cannot always be frozen here. Deferred constants do not
9572 -- freeze their type (which often enough will be private).
9574 if Nkind
(P
) = N_Object_Declaration
9575 and then Constant_Present
(P
)
9576 and then No
(Expression
(P
))
9581 Insert_Actions
(Obj_Def
, Freeze_Entity
(T
, Sloc
(P
)));
9585 T
:= Process_Subtype
(Obj_Def
, Related_Nod
);
9589 end Find_Type_Of_Object
;
9591 --------------------------------
9592 -- Find_Type_Of_Subtype_Indic --
9593 --------------------------------
9595 function Find_Type_Of_Subtype_Indic
(S
: Node_Id
) return Entity_Id
is
9599 -- Case of subtype mark with a constraint
9601 if Nkind
(S
) = N_Subtype_Indication
then
9602 Find_Type
(Subtype_Mark
(S
));
9603 Typ
:= Entity
(Subtype_Mark
(S
));
9606 Is_Valid_Constraint_Kind
(Ekind
(Typ
), Nkind
(Constraint
(S
)))
9609 ("incorrect constraint for this kind of type", Constraint
(S
));
9610 Rewrite
(S
, New_Copy_Tree
(Subtype_Mark
(S
)));
9613 -- Otherwise we have a subtype mark without a constraint
9615 elsif Error_Posted
(S
) then
9616 Rewrite
(S
, New_Occurrence_Of
(Any_Id
, Sloc
(S
)));
9624 if Typ
= Standard_Wide_Character
9625 or else Typ
= Standard_Wide_String
9627 Check_Restriction
(No_Wide_Characters
, S
);
9631 end Find_Type_Of_Subtype_Indic
;
9633 -------------------------------------
9634 -- Floating_Point_Type_Declaration --
9635 -------------------------------------
9637 procedure Floating_Point_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
) is
9638 Digs
: constant Node_Id
:= Digits_Expression
(Def
);
9640 Base_Typ
: Entity_Id
;
9641 Implicit_Base
: Entity_Id
;
9644 function Can_Derive_From
(E
: Entity_Id
) return Boolean;
9645 -- Find if given digits value allows derivation from specified type
9647 ---------------------
9648 -- Can_Derive_From --
9649 ---------------------
9651 function Can_Derive_From
(E
: Entity_Id
) return Boolean is
9652 Spec
: constant Entity_Id
:= Real_Range_Specification
(Def
);
9655 if Digs_Val
> Digits_Value
(E
) then
9659 if Present
(Spec
) then
9660 if Expr_Value_R
(Type_Low_Bound
(E
)) >
9661 Expr_Value_R
(Low_Bound
(Spec
))
9666 if Expr_Value_R
(Type_High_Bound
(E
)) <
9667 Expr_Value_R
(High_Bound
(Spec
))
9674 end Can_Derive_From
;
9676 -- Start of processing for Floating_Point_Type_Declaration
9679 Check_Restriction
(No_Floating_Point
, Def
);
9681 -- Create an implicit base type
9684 Create_Itype
(E_Floating_Point_Type
, Parent
(Def
), T
, 'B');
9686 -- Analyze and verify digits value
9688 Analyze_And_Resolve
(Digs
, Any_Integer
);
9689 Check_Digits_Expression
(Digs
);
9690 Digs_Val
:= Expr_Value
(Digs
);
9692 -- Process possible range spec and find correct type to derive from
9694 Process_Real_Range_Specification
(Def
);
9696 if Can_Derive_From
(Standard_Short_Float
) then
9697 Base_Typ
:= Standard_Short_Float
;
9698 elsif Can_Derive_From
(Standard_Float
) then
9699 Base_Typ
:= Standard_Float
;
9700 elsif Can_Derive_From
(Standard_Long_Float
) then
9701 Base_Typ
:= Standard_Long_Float
;
9702 elsif Can_Derive_From
(Standard_Long_Long_Float
) then
9703 Base_Typ
:= Standard_Long_Long_Float
;
9705 -- If we can't derive from any existing type, use long long float
9706 -- and give appropriate message explaining the problem.
9709 Base_Typ
:= Standard_Long_Long_Float
;
9711 if Digs_Val
>= Digits_Value
(Standard_Long_Long_Float
) then
9712 Error_Msg_Uint_1
:= Digits_Value
(Standard_Long_Long_Float
);
9713 Error_Msg_N
("digits value out of range, maximum is ^", Digs
);
9717 ("range too large for any predefined type",
9718 Real_Range_Specification
(Def
));
9722 -- If there are bounds given in the declaration use them as the bounds
9723 -- of the type, otherwise use the bounds of the predefined base type
9724 -- that was chosen based on the Digits value.
9726 if Present
(Real_Range_Specification
(Def
)) then
9727 Set_Scalar_Range
(T
, Real_Range_Specification
(Def
));
9728 Set_Is_Constrained
(T
);
9730 -- The bounds of this range must be converted to machine numbers
9731 -- in accordance with RM 4.9(38).
9733 Bound
:= Type_Low_Bound
(T
);
9735 if Nkind
(Bound
) = N_Real_Literal
then
9737 (Bound
, Machine
(Base_Typ
, Realval
(Bound
), Round
, Bound
));
9738 Set_Is_Machine_Number
(Bound
);
9741 Bound
:= Type_High_Bound
(T
);
9743 if Nkind
(Bound
) = N_Real_Literal
then
9745 (Bound
, Machine
(Base_Typ
, Realval
(Bound
), Round
, Bound
));
9746 Set_Is_Machine_Number
(Bound
);
9750 Set_Scalar_Range
(T
, Scalar_Range
(Base_Typ
));
9753 -- Complete definition of implicit base and declared first subtype
9755 Set_Etype
(Implicit_Base
, Base_Typ
);
9757 Set_Scalar_Range
(Implicit_Base
, Scalar_Range
(Base_Typ
));
9758 Set_Size_Info
(Implicit_Base
, (Base_Typ
));
9759 Set_RM_Size
(Implicit_Base
, RM_Size
(Base_Typ
));
9760 Set_First_Rep_Item
(Implicit_Base
, First_Rep_Item
(Base_Typ
));
9761 Set_Digits_Value
(Implicit_Base
, Digits_Value
(Base_Typ
));
9762 Set_Vax_Float
(Implicit_Base
, Vax_Float
(Base_Typ
));
9764 Set_Ekind
(T
, E_Floating_Point_Subtype
);
9765 Set_Etype
(T
, Implicit_Base
);
9767 Set_Size_Info
(T
, (Implicit_Base
));
9768 Set_RM_Size
(T
, RM_Size
(Implicit_Base
));
9769 Set_First_Rep_Item
(T
, First_Rep_Item
(Implicit_Base
));
9770 Set_Digits_Value
(T
, Digs_Val
);
9772 end Floating_Point_Type_Declaration
;
9774 ----------------------------
9775 -- Get_Discriminant_Value --
9776 ----------------------------
9778 -- This is the situation...
9780 -- There is a non-derived type
9782 -- type T0 (Dx, Dy, Dz...)
9784 -- There are zero or more levels of derivation, with each
9785 -- derivation either purely inheriting the discriminants, or
9786 -- defining its own.
9788 -- type Ti is new Ti-1
9790 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
9792 -- subtype Ti is ...
9794 -- The subtype issue is avoided by the use of
9795 -- Original_Record_Component, and the fact that derived subtypes
9796 -- also derive the constraints.
9798 -- This chain leads back from
9800 -- Typ_For_Constraint
9802 -- Typ_For_Constraint has discriminants, and the value for each
9803 -- discriminant is given by its corresponding Elmt of Constraints.
9805 -- Discriminant is some discriminant in this hierarchy.
9807 -- We need to return its value.
9809 -- We do this by recursively searching each level, and looking for
9810 -- Discriminant. Once we get to the bottom, we start backing up
9811 -- returning the value for it which may in turn be a discriminant
9812 -- further up, so on the backup we continue the substitution.
9814 function Get_Discriminant_Value
9815 (Discriminant
: Entity_Id
;
9816 Typ_For_Constraint
: Entity_Id
;
9817 Constraint
: Elist_Id
) return Node_Id
9819 function Search_Derivation_Levels
9821 Discrim_Values
: Elist_Id
;
9822 Stored_Discrim_Values
: Boolean) return Node_Or_Entity_Id
;
9823 -- This is the routine that performs the recursive search of levels
9824 -- as described above.
9826 ------------------------------
9827 -- Search_Derivation_Levels --
9828 ------------------------------
9830 function Search_Derivation_Levels
9832 Discrim_Values
: Elist_Id
;
9833 Stored_Discrim_Values
: Boolean) return Node_Or_Entity_Id
9837 Result
: Node_Or_Entity_Id
;
9838 Result_Entity
: Node_Id
;
9841 -- If inappropriate type, return Error, this happens only in
9842 -- cascaded error situations, and we want to avoid a blow up.
9844 if not Is_Composite_Type
(Ti
) or else Is_Array_Type
(Ti
) then
9848 -- Look deeper if possible. Use Stored_Constraints only for
9849 -- untagged types. For tagged types use the given constraint.
9850 -- This asymmetry needs explanation???
9852 if not Stored_Discrim_Values
9853 and then Present
(Stored_Constraint
(Ti
))
9854 and then not Is_Tagged_Type
(Ti
)
9857 Search_Derivation_Levels
(Ti
, Stored_Constraint
(Ti
), True);
9860 Td
: constant Entity_Id
:= Etype
(Ti
);
9864 Result
:= Discriminant
;
9867 if Present
(Stored_Constraint
(Ti
)) then
9869 Search_Derivation_Levels
9870 (Td
, Stored_Constraint
(Ti
), True);
9873 Search_Derivation_Levels
9874 (Td
, Discrim_Values
, Stored_Discrim_Values
);
9880 -- Extra underlying places to search, if not found above. For
9881 -- concurrent types, the relevant discriminant appears in the
9882 -- corresponding record. For a type derived from a private type
9883 -- without discriminant, the full view inherits the discriminants
9884 -- of the full view of the parent.
9886 if Result
= Discriminant
then
9887 if Is_Concurrent_Type
(Ti
)
9888 and then Present
(Corresponding_Record_Type
(Ti
))
9891 Search_Derivation_Levels
(
9892 Corresponding_Record_Type
(Ti
),
9894 Stored_Discrim_Values
);
9896 elsif Is_Private_Type
(Ti
)
9897 and then not Has_Discriminants
(Ti
)
9898 and then Present
(Full_View
(Ti
))
9899 and then Etype
(Full_View
(Ti
)) /= Ti
9902 Search_Derivation_Levels
(
9905 Stored_Discrim_Values
);
9909 -- If Result is not a (reference to a) discriminant,
9910 -- return it, otherwise set Result_Entity to the discriminant.
9912 if Nkind
(Result
) = N_Defining_Identifier
then
9914 pragma Assert
(Result
= Discriminant
);
9916 Result_Entity
:= Result
;
9919 if not Denotes_Discriminant
(Result
) then
9923 Result_Entity
:= Entity
(Result
);
9926 -- See if this level of derivation actually has discriminants
9927 -- because tagged derivations can add them, hence the lower
9928 -- levels need not have any.
9930 if not Has_Discriminants
(Ti
) then
9934 -- Scan Ti's discriminants for Result_Entity,
9935 -- and return its corresponding value, if any.
9937 Result_Entity
:= Original_Record_Component
(Result_Entity
);
9939 Assoc
:= First_Elmt
(Discrim_Values
);
9941 if Stored_Discrim_Values
then
9942 Disc
:= First_Stored_Discriminant
(Ti
);
9944 Disc
:= First_Discriminant
(Ti
);
9947 while Present
(Disc
) loop
9949 pragma Assert
(Present
(Assoc
));
9951 if Original_Record_Component
(Disc
) = Result_Entity
then
9952 return Node
(Assoc
);
9957 if Stored_Discrim_Values
then
9958 Next_Stored_Discriminant
(Disc
);
9960 Next_Discriminant
(Disc
);
9964 -- Could not find it
9967 end Search_Derivation_Levels
;
9969 Result
: Node_Or_Entity_Id
;
9971 -- Start of processing for Get_Discriminant_Value
9974 -- ??? this routine is a gigantic mess and will be deleted.
9975 -- for the time being just test for the trivial case before calling
9978 if Base_Type
(Scope
(Discriminant
)) = Base_Type
(Typ_For_Constraint
) then
9980 D
: Entity_Id
:= First_Discriminant
(Typ_For_Constraint
);
9981 E
: Elmt_Id
:= First_Elmt
(Constraint
);
9983 while Present
(D
) loop
9984 if Chars
(D
) = Chars
(Discriminant
) then
9988 Next_Discriminant
(D
);
9994 Result
:= Search_Derivation_Levels
9995 (Typ_For_Constraint
, Constraint
, False);
9997 -- ??? hack to disappear when this routine is gone
9999 if Nkind
(Result
) = N_Defining_Identifier
then
10001 D
: Entity_Id
:= First_Discriminant
(Typ_For_Constraint
);
10002 E
: Elmt_Id
:= First_Elmt
(Constraint
);
10005 while Present
(D
) loop
10006 if Corresponding_Discriminant
(D
) = Discriminant
then
10010 Next_Discriminant
(D
);
10016 pragma Assert
(Nkind
(Result
) /= N_Defining_Identifier
);
10018 end Get_Discriminant_Value
;
10020 --------------------------
10021 -- Has_Range_Constraint --
10022 --------------------------
10024 function Has_Range_Constraint
(N
: Node_Id
) return Boolean is
10025 C
: constant Node_Id
:= Constraint
(N
);
10028 if Nkind
(C
) = N_Range_Constraint
then
10031 elsif Nkind
(C
) = N_Digits_Constraint
then
10033 Is_Decimal_Fixed_Point_Type
(Entity
(Subtype_Mark
(N
)))
10035 Present
(Range_Constraint
(C
));
10037 elsif Nkind
(C
) = N_Delta_Constraint
then
10038 return Present
(Range_Constraint
(C
));
10043 end Has_Range_Constraint
;
10045 ------------------------
10046 -- Inherit_Components --
10047 ------------------------
10049 function Inherit_Components
10051 Parent_Base
: Entity_Id
;
10052 Derived_Base
: Entity_Id
;
10053 Is_Tagged
: Boolean;
10054 Inherit_Discr
: Boolean;
10055 Discs
: Elist_Id
) return Elist_Id
10057 Assoc_List
: constant Elist_Id
:= New_Elmt_List
;
10059 procedure Inherit_Component
10060 (Old_C
: Entity_Id
;
10061 Plain_Discrim
: Boolean := False;
10062 Stored_Discrim
: Boolean := False);
10063 -- Inherits component Old_C from Parent_Base to the Derived_Base.
10064 -- If Plain_Discrim is True, Old_C is a discriminant.
10065 -- If Stored_Discrim is True, Old_C is a stored discriminant.
10066 -- If they are both false then Old_C is a regular component.
10068 -----------------------
10069 -- Inherit_Component --
10070 -----------------------
10072 procedure Inherit_Component
10073 (Old_C
: Entity_Id
;
10074 Plain_Discrim
: Boolean := False;
10075 Stored_Discrim
: Boolean := False)
10077 New_C
: constant Entity_Id
:= New_Copy
(Old_C
);
10079 Discrim
: Entity_Id
;
10080 Corr_Discrim
: Entity_Id
;
10083 pragma Assert
(not Is_Tagged
or else not Stored_Discrim
);
10085 Set_Parent
(New_C
, Parent
(Old_C
));
10087 -- Regular discriminants and components must be inserted
10088 -- in the scope of the Derived_Base. Do it here.
10090 if not Stored_Discrim
then
10091 Enter_Name
(New_C
);
10094 -- For tagged types the Original_Record_Component must point to
10095 -- whatever this field was pointing to in the parent type. This has
10096 -- already been achieved by the call to New_Copy above.
10098 if not Is_Tagged
then
10099 Set_Original_Record_Component
(New_C
, New_C
);
10102 -- If we have inherited a component then see if its Etype contains
10103 -- references to Parent_Base discriminants. In this case, replace
10104 -- these references with the constraints given in Discs. We do not
10105 -- do this for the partial view of private types because this is
10106 -- not needed (only the components of the full view will be used
10107 -- for code generation) and cause problem. We also avoid this
10108 -- transformation in some error situations.
10110 if Ekind
(New_C
) = E_Component
then
10111 if (Is_Private_Type
(Derived_Base
)
10112 and then not Is_Generic_Type
(Derived_Base
))
10113 or else (Is_Empty_Elmt_List
(Discs
)
10114 and then not Expander_Active
)
10116 Set_Etype
(New_C
, Etype
(Old_C
));
10118 Set_Etype
(New_C
, Constrain_Component_Type
(Etype
(Old_C
),
10119 Derived_Base
, N
, Parent_Base
, Discs
));
10123 -- In derived tagged types it is illegal to reference a non
10124 -- discriminant component in the parent type. To catch this, mark
10125 -- these components with an Ekind of E_Void. This will be reset in
10126 -- Record_Type_Definition after processing the record extension of
10127 -- the derived type.
10129 if Is_Tagged
and then Ekind
(New_C
) = E_Component
then
10130 Set_Ekind
(New_C
, E_Void
);
10133 if Plain_Discrim
then
10134 Set_Corresponding_Discriminant
(New_C
, Old_C
);
10135 Build_Discriminal
(New_C
);
10137 -- If we are explicitly inheriting a stored discriminant it will be
10138 -- completely hidden.
10140 elsif Stored_Discrim
then
10141 Set_Corresponding_Discriminant
(New_C
, Empty
);
10142 Set_Discriminal
(New_C
, Empty
);
10143 Set_Is_Completely_Hidden
(New_C
);
10145 -- Set the Original_Record_Component of each discriminant in the
10146 -- derived base to point to the corresponding stored that we just
10149 Discrim
:= First_Discriminant
(Derived_Base
);
10150 while Present
(Discrim
) loop
10151 Corr_Discrim
:= Corresponding_Discriminant
(Discrim
);
10153 -- Corr_Discrimm could be missing in an error situation.
10155 if Present
(Corr_Discrim
)
10156 and then Original_Record_Component
(Corr_Discrim
) = Old_C
10158 Set_Original_Record_Component
(Discrim
, New_C
);
10161 Next_Discriminant
(Discrim
);
10164 Append_Entity
(New_C
, Derived_Base
);
10167 if not Is_Tagged
then
10168 Append_Elmt
(Old_C
, Assoc_List
);
10169 Append_Elmt
(New_C
, Assoc_List
);
10171 end Inherit_Component
;
10173 -- Variables local to Inherit_Components.
10175 Loc
: constant Source_Ptr
:= Sloc
(N
);
10177 Parent_Discrim
: Entity_Id
;
10178 Stored_Discrim
: Entity_Id
;
10181 Component
: Entity_Id
;
10183 -- Start of processing for Inherit_Components
10186 if not Is_Tagged
then
10187 Append_Elmt
(Parent_Base
, Assoc_List
);
10188 Append_Elmt
(Derived_Base
, Assoc_List
);
10191 -- Inherit parent discriminants if needed.
10193 if Inherit_Discr
then
10194 Parent_Discrim
:= First_Discriminant
(Parent_Base
);
10195 while Present
(Parent_Discrim
) loop
10196 Inherit_Component
(Parent_Discrim
, Plain_Discrim
=> True);
10197 Next_Discriminant
(Parent_Discrim
);
10201 -- Create explicit stored discrims for untagged types when necessary.
10203 if not Has_Unknown_Discriminants
(Derived_Base
)
10204 and then Has_Discriminants
(Parent_Base
)
10205 and then not Is_Tagged
10208 or else First_Discriminant
(Parent_Base
) /=
10209 First_Stored_Discriminant
(Parent_Base
))
10211 Stored_Discrim
:= First_Stored_Discriminant
(Parent_Base
);
10212 while Present
(Stored_Discrim
) loop
10213 Inherit_Component
(Stored_Discrim
, Stored_Discrim
=> True);
10214 Next_Stored_Discriminant
(Stored_Discrim
);
10218 -- See if we can apply the second transformation for derived types, as
10219 -- explained in point 6. in the comments above Build_Derived_Record_Type
10220 -- This is achieved by appending Derived_Base discriminants into
10221 -- Discs, which has the side effect of returning a non empty Discs
10222 -- list to the caller of Inherit_Components, which is what we want.
10225 and then Is_Empty_Elmt_List
(Discs
)
10226 and then (not Is_Private_Type
(Derived_Base
)
10227 or Is_Generic_Type
(Derived_Base
))
10229 D
:= First_Discriminant
(Derived_Base
);
10230 while Present
(D
) loop
10231 Append_Elmt
(New_Reference_To
(D
, Loc
), Discs
);
10232 Next_Discriminant
(D
);
10236 -- Finally, inherit non-discriminant components unless they are not
10237 -- visible because defined or inherited from the full view of the
10238 -- parent. Don't inherit the _parent field of the parent type.
10240 Component
:= First_Entity
(Parent_Base
);
10241 while Present
(Component
) loop
10242 if Ekind
(Component
) /= E_Component
10243 or else Chars
(Component
) = Name_uParent
10247 -- If the derived type is within the parent type's declarative
10248 -- region, then the components can still be inherited even though
10249 -- they aren't visible at this point. This can occur for cases
10250 -- such as within public child units where the components must
10251 -- become visible upon entering the child unit's private part.
10253 elsif not Is_Visible_Component
(Component
)
10254 and then not In_Open_Scopes
(Scope
(Parent_Base
))
10258 elsif Ekind
(Derived_Base
) = E_Private_Type
10259 or else Ekind
(Derived_Base
) = E_Limited_Private_Type
10264 Inherit_Component
(Component
);
10267 Next_Entity
(Component
);
10270 -- For tagged derived types, inherited discriminants cannot be used in
10271 -- component declarations of the record extension part. To achieve this
10272 -- we mark the inherited discriminants as not visible.
10274 if Is_Tagged
and then Inherit_Discr
then
10275 D
:= First_Discriminant
(Derived_Base
);
10276 while Present
(D
) loop
10277 Set_Is_Immediately_Visible
(D
, False);
10278 Next_Discriminant
(D
);
10283 end Inherit_Components
;
10285 ------------------------------
10286 -- Is_Valid_Constraint_Kind --
10287 ------------------------------
10289 function Is_Valid_Constraint_Kind
10290 (T_Kind
: Type_Kind
;
10291 Constraint_Kind
: Node_Kind
) return Boolean
10296 when Enumeration_Kind |
10298 return Constraint_Kind
= N_Range_Constraint
;
10300 when Decimal_Fixed_Point_Kind
=>
10302 Constraint_Kind
= N_Digits_Constraint
10304 Constraint_Kind
= N_Range_Constraint
;
10306 when Ordinary_Fixed_Point_Kind
=>
10308 Constraint_Kind
= N_Delta_Constraint
10310 Constraint_Kind
= N_Range_Constraint
;
10314 Constraint_Kind
= N_Digits_Constraint
10316 Constraint_Kind
= N_Range_Constraint
;
10323 E_Incomplete_Type |
10326 return Constraint_Kind
= N_Index_Or_Discriminant_Constraint
;
10329 return True; -- Error will be detected later.
10332 end Is_Valid_Constraint_Kind
;
10334 --------------------------
10335 -- Is_Visible_Component --
10336 --------------------------
10338 function Is_Visible_Component
(C
: Entity_Id
) return Boolean is
10339 Original_Comp
: Entity_Id
:= Empty
;
10340 Original_Scope
: Entity_Id
;
10341 Type_Scope
: Entity_Id
;
10343 function Is_Local_Type
(Typ
: Entity_Id
) return Boolean;
10344 -- Check whether parent type of inherited component is declared
10345 -- locally, possibly within a nested package or instance. The
10346 -- current scope is the derived record itself.
10348 -------------------
10349 -- Is_Local_Type --
10350 -------------------
10352 function Is_Local_Type
(Typ
: Entity_Id
) return Boolean is
10353 Scop
: Entity_Id
:= Scope
(Typ
);
10356 while Present
(Scop
)
10357 and then Scop
/= Standard_Standard
10359 if Scop
= Scope
(Current_Scope
) then
10363 Scop
:= Scope
(Scop
);
10368 -- Start of processing for Is_Visible_Component
10371 if Ekind
(C
) = E_Component
10372 or else Ekind
(C
) = E_Discriminant
10374 Original_Comp
:= Original_Record_Component
(C
);
10377 if No
(Original_Comp
) then
10379 -- Premature usage, or previous error
10384 Original_Scope
:= Scope
(Original_Comp
);
10385 Type_Scope
:= Scope
(Base_Type
(Scope
(C
)));
10388 -- This test only concerns tagged types
10390 if not Is_Tagged_Type
(Original_Scope
) then
10393 -- If it is _Parent or _Tag, there is no visibility issue
10395 elsif not Comes_From_Source
(Original_Comp
) then
10398 -- If we are in the body of an instantiation, the component is
10399 -- visible even when the parent type (possibly defined in an
10400 -- enclosing unit or in a parent unit) might not.
10402 elsif In_Instance_Body
then
10405 -- Discriminants are always visible.
10407 elsif Ekind
(Original_Comp
) = E_Discriminant
10408 and then not Has_Unknown_Discriminants
(Original_Scope
)
10412 -- If the component has been declared in an ancestor which is
10413 -- currently a private type, then it is not visible. The same
10414 -- applies if the component's containing type is not in an
10415 -- open scope and the original component's enclosing type
10416 -- is a visible full type of a private type (which can occur
10417 -- in cases where an attempt is being made to reference a
10418 -- component in a sibling package that is inherited from a
10419 -- visible component of a type in an ancestor package; the
10420 -- component in the sibling package should not be visible
10421 -- even though the component it inherited from is visible).
10422 -- This does not apply however in the case where the scope
10423 -- of the type is a private child unit, or when the parent
10424 -- comes from a local package in which the ancestor is
10425 -- currently visible. The latter suppression of visibility
10426 -- is needed for cases that are tested in B730006.
10428 elsif Is_Private_Type
(Original_Scope
)
10430 (not Is_Private_Descendant
(Type_Scope
)
10431 and then not In_Open_Scopes
(Type_Scope
)
10432 and then Has_Private_Declaration
(Original_Scope
))
10434 -- If the type derives from an entity in a formal package, there
10435 -- are no additional visible components.
10437 if Nkind
(Original_Node
(Unit_Declaration_Node
(Type_Scope
))) =
10438 N_Formal_Package_Declaration
10442 -- if we are not in the private part of the current package, there
10443 -- are no additional visible components.
10445 elsif Ekind
(Scope
(Current_Scope
)) = E_Package
10446 and then not In_Private_Part
(Scope
(Current_Scope
))
10451 Is_Child_Unit
(Cunit_Entity
(Current_Sem_Unit
))
10452 and then Is_Local_Type
(Type_Scope
);
10455 -- There is another weird way in which a component may be invisible
10456 -- when the private and the full view are not derived from the same
10457 -- ancestor. Here is an example :
10459 -- type A1 is tagged record F1 : integer; end record;
10460 -- type A2 is new A1 with record F2 : integer; end record;
10461 -- type T is new A1 with private;
10463 -- type T is new A2 with null record;
10465 -- In this case, the full view of T inherits F1 and F2 but the
10466 -- private view inherits only F1
10470 Ancestor
: Entity_Id
:= Scope
(C
);
10474 if Ancestor
= Original_Scope
then
10476 elsif Ancestor
= Etype
(Ancestor
) then
10480 Ancestor
:= Etype
(Ancestor
);
10486 end Is_Visible_Component
;
10488 --------------------------
10489 -- Make_Class_Wide_Type --
10490 --------------------------
10492 procedure Make_Class_Wide_Type
(T
: Entity_Id
) is
10493 CW_Type
: Entity_Id
;
10495 Next_E
: Entity_Id
;
10498 -- The class wide type can have been defined by the partial view in
10499 -- which case everything is already done
10501 if Present
(Class_Wide_Type
(T
)) then
10506 New_External_Entity
(E_Void
, Scope
(T
), Sloc
(T
), T
, 'C', 0, 'T');
10508 -- Inherit root type characteristics
10510 CW_Name
:= Chars
(CW_Type
);
10511 Next_E
:= Next_Entity
(CW_Type
);
10512 Copy_Node
(T
, CW_Type
);
10513 Set_Comes_From_Source
(CW_Type
, False);
10514 Set_Chars
(CW_Type
, CW_Name
);
10515 Set_Parent
(CW_Type
, Parent
(T
));
10516 Set_Next_Entity
(CW_Type
, Next_E
);
10517 Set_Has_Delayed_Freeze
(CW_Type
);
10519 -- Customize the class-wide type: It has no prim. op., it cannot be
10520 -- abstract and its Etype points back to the specific root type.
10522 Set_Ekind
(CW_Type
, E_Class_Wide_Type
);
10523 Set_Is_Tagged_Type
(CW_Type
, True);
10524 Set_Primitive_Operations
(CW_Type
, New_Elmt_List
);
10525 Set_Is_Abstract
(CW_Type
, False);
10526 Set_Is_Constrained
(CW_Type
, False);
10527 Set_Is_First_Subtype
(CW_Type
, Is_First_Subtype
(T
));
10528 Init_Size_Align
(CW_Type
);
10530 if Ekind
(T
) = E_Class_Wide_Subtype
then
10531 Set_Etype
(CW_Type
, Etype
(Base_Type
(T
)));
10533 Set_Etype
(CW_Type
, T
);
10536 -- If this is the class_wide type of a constrained subtype, it does
10537 -- not have discriminants.
10539 Set_Has_Discriminants
(CW_Type
,
10540 Has_Discriminants
(T
) and then not Is_Constrained
(T
));
10542 Set_Has_Unknown_Discriminants
(CW_Type
, True);
10543 Set_Class_Wide_Type
(T
, CW_Type
);
10544 Set_Equivalent_Type
(CW_Type
, Empty
);
10546 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
10548 Set_Class_Wide_Type
(CW_Type
, CW_Type
);
10550 end Make_Class_Wide_Type
;
10556 procedure Make_Index
10558 Related_Nod
: Node_Id
;
10559 Related_Id
: Entity_Id
:= Empty
;
10560 Suffix_Index
: Nat
:= 1)
10564 Def_Id
: Entity_Id
:= Empty
;
10565 Found
: Boolean := False;
10568 -- For a discrete range used in a constrained array definition and
10569 -- defined by a range, an implicit conversion to the predefined type
10570 -- INTEGER is assumed if each bound is either a numeric literal, a named
10571 -- number, or an attribute, and the type of both bounds (prior to the
10572 -- implicit conversion) is the type universal_integer. Otherwise, both
10573 -- bounds must be of the same discrete type, other than universal
10574 -- integer; this type must be determinable independently of the
10575 -- context, but using the fact that the type must be discrete and that
10576 -- both bounds must have the same type.
10578 -- Character literals also have a universal type in the absence of
10579 -- of additional context, and are resolved to Standard_Character.
10581 if Nkind
(I
) = N_Range
then
10583 -- The index is given by a range constraint. The bounds are known
10584 -- to be of a consistent type.
10586 if not Is_Overloaded
(I
) then
10589 -- If the bounds are universal, choose the specific predefined
10592 if T
= Universal_Integer
then
10593 T
:= Standard_Integer
;
10595 elsif T
= Any_Character
then
10599 ("ambiguous character literals (could be Wide_Character)",
10603 T
:= Standard_Character
;
10610 Ind
: Interp_Index
;
10614 Get_First_Interp
(I
, Ind
, It
);
10616 while Present
(It
.Typ
) loop
10617 if Is_Discrete_Type
(It
.Typ
) then
10620 and then not Covers
(It
.Typ
, T
)
10621 and then not Covers
(T
, It
.Typ
)
10623 Error_Msg_N
("ambiguous bounds in discrete range", I
);
10631 Get_Next_Interp
(Ind
, It
);
10634 if T
= Any_Type
then
10635 Error_Msg_N
("discrete type required for range", I
);
10636 Set_Etype
(I
, Any_Type
);
10639 elsif T
= Universal_Integer
then
10640 T
:= Standard_Integer
;
10645 if not Is_Discrete_Type
(T
) then
10646 Error_Msg_N
("discrete type required for range", I
);
10647 Set_Etype
(I
, Any_Type
);
10651 if Nkind
(Low_Bound
(I
)) = N_Attribute_Reference
10652 and then Attribute_Name
(Low_Bound
(I
)) = Name_First
10653 and then Is_Entity_Name
(Prefix
(Low_Bound
(I
)))
10654 and then Is_Type
(Entity
(Prefix
(Low_Bound
(I
))))
10655 and then Is_Discrete_Type
(Entity
(Prefix
(Low_Bound
(I
))))
10657 -- The type of the index will be the type of the prefix,
10658 -- as long as the upper bound is 'Last of the same type.
10660 Def_Id
:= Entity
(Prefix
(Low_Bound
(I
)));
10662 if Nkind
(High_Bound
(I
)) /= N_Attribute_Reference
10663 or else Attribute_Name
(High_Bound
(I
)) /= Name_Last
10664 or else not Is_Entity_Name
(Prefix
(High_Bound
(I
)))
10665 or else Entity
(Prefix
(High_Bound
(I
))) /= Def_Id
10672 Process_Range_Expr_In_Decl
(R
, T
);
10674 elsif Nkind
(I
) = N_Subtype_Indication
then
10676 -- The index is given by a subtype with a range constraint.
10678 T
:= Base_Type
(Entity
(Subtype_Mark
(I
)));
10680 if not Is_Discrete_Type
(T
) then
10681 Error_Msg_N
("discrete type required for range", I
);
10682 Set_Etype
(I
, Any_Type
);
10686 R
:= Range_Expression
(Constraint
(I
));
10689 Process_Range_Expr_In_Decl
(R
, Entity
(Subtype_Mark
(I
)));
10691 elsif Nkind
(I
) = N_Attribute_Reference
then
10693 -- The parser guarantees that the attribute is a RANGE attribute
10695 -- If the node denotes the range of a type mark, that is also the
10696 -- resulting type, and we do no need to create an Itype for it.
10698 if Is_Entity_Name
(Prefix
(I
))
10699 and then Comes_From_Source
(I
)
10700 and then Is_Type
(Entity
(Prefix
(I
)))
10701 and then Is_Discrete_Type
(Entity
(Prefix
(I
)))
10703 Def_Id
:= Entity
(Prefix
(I
));
10706 Analyze_And_Resolve
(I
);
10710 -- If none of the above, must be a subtype. We convert this to a
10711 -- range attribute reference because in the case of declared first
10712 -- named subtypes, the types in the range reference can be different
10713 -- from the type of the entity. A range attribute normalizes the
10714 -- reference and obtains the correct types for the bounds.
10716 -- This transformation is in the nature of an expansion, is only
10717 -- done if expansion is active. In particular, it is not done on
10718 -- formal generic types, because we need to retain the name of the
10719 -- original index for instantiation purposes.
10722 if not Is_Entity_Name
(I
) or else not Is_Type
(Entity
(I
)) then
10723 Error_Msg_N
("invalid subtype mark in discrete range ", I
);
10724 Set_Etype
(I
, Any_Integer
);
10727 -- The type mark may be that of an incomplete type. It is only
10728 -- now that we can get the full view, previous analysis does
10729 -- not look specifically for a type mark.
10731 Set_Entity
(I
, Get_Full_View
(Entity
(I
)));
10732 Set_Etype
(I
, Entity
(I
));
10733 Def_Id
:= Entity
(I
);
10735 if not Is_Discrete_Type
(Def_Id
) then
10736 Error_Msg_N
("discrete type required for index", I
);
10737 Set_Etype
(I
, Any_Type
);
10742 if Expander_Active
then
10744 Make_Attribute_Reference
(Sloc
(I
),
10745 Attribute_Name
=> Name_Range
,
10746 Prefix
=> Relocate_Node
(I
)));
10748 -- The original was a subtype mark that does not freeze. This
10749 -- means that the rewritten version must not freeze either.
10751 Set_Must_Not_Freeze
(I
);
10752 Set_Must_Not_Freeze
(Prefix
(I
));
10754 -- Is order critical??? if so, document why, if not
10755 -- use Analyze_And_Resolve
10762 -- If expander is inactive, type is legal, nothing else to construct
10769 if not Is_Discrete_Type
(T
) then
10770 Error_Msg_N
("discrete type required for range", I
);
10771 Set_Etype
(I
, Any_Type
);
10774 elsif T
= Any_Type
then
10775 Set_Etype
(I
, Any_Type
);
10779 -- We will now create the appropriate Itype to describe the
10780 -- range, but first a check. If we originally had a subtype,
10781 -- then we just label the range with this subtype. Not only
10782 -- is there no need to construct a new subtype, but it is wrong
10783 -- to do so for two reasons:
10785 -- 1. A legality concern, if we have a subtype, it must not
10786 -- freeze, and the Itype would cause freezing incorrectly
10788 -- 2. An efficiency concern, if we created an Itype, it would
10789 -- not be recognized as the same type for the purposes of
10790 -- eliminating checks in some circumstances.
10792 -- We signal this case by setting the subtype entity in Def_Id.
10794 if No
(Def_Id
) then
10797 Create_Itype
(E_Void
, Related_Nod
, Related_Id
, 'D', Suffix_Index
);
10798 Set_Etype
(Def_Id
, Base_Type
(T
));
10800 if Is_Signed_Integer_Type
(T
) then
10801 Set_Ekind
(Def_Id
, E_Signed_Integer_Subtype
);
10803 elsif Is_Modular_Integer_Type
(T
) then
10804 Set_Ekind
(Def_Id
, E_Modular_Integer_Subtype
);
10807 Set_Ekind
(Def_Id
, E_Enumeration_Subtype
);
10808 Set_Is_Character_Type
(Def_Id
, Is_Character_Type
(T
));
10809 Set_First_Literal
(Def_Id
, First_Literal
(T
));
10812 Set_Size_Info
(Def_Id
, (T
));
10813 Set_RM_Size
(Def_Id
, RM_Size
(T
));
10814 Set_First_Rep_Item
(Def_Id
, First_Rep_Item
(T
));
10816 Set_Scalar_Range
(Def_Id
, R
);
10817 Conditional_Delay
(Def_Id
, T
);
10819 -- In the subtype indication case, if the immediate parent of the
10820 -- new subtype is non-static, then the subtype we create is non-
10821 -- static, even if its bounds are static.
10823 if Nkind
(I
) = N_Subtype_Indication
10824 and then not Is_Static_Subtype
(Entity
(Subtype_Mark
(I
)))
10826 Set_Is_Non_Static_Subtype
(Def_Id
);
10830 -- Final step is to label the index with this constructed type
10832 Set_Etype
(I
, Def_Id
);
10835 ------------------------------
10836 -- Modular_Type_Declaration --
10837 ------------------------------
10839 procedure Modular_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
) is
10840 Mod_Expr
: constant Node_Id
:= Expression
(Def
);
10843 procedure Set_Modular_Size
(Bits
: Int
);
10844 -- Sets RM_Size to Bits, and Esize to normal word size above this
10846 ----------------------
10847 -- Set_Modular_Size --
10848 ----------------------
10850 procedure Set_Modular_Size
(Bits
: Int
) is
10852 Set_RM_Size
(T
, UI_From_Int
(Bits
));
10857 elsif Bits
<= 16 then
10858 Init_Esize
(T
, 16);
10860 elsif Bits
<= 32 then
10861 Init_Esize
(T
, 32);
10864 Init_Esize
(T
, System_Max_Binary_Modulus_Power
);
10866 end Set_Modular_Size
;
10868 -- Start of processing for Modular_Type_Declaration
10871 Analyze_And_Resolve
(Mod_Expr
, Any_Integer
);
10873 Set_Ekind
(T
, E_Modular_Integer_Type
);
10874 Init_Alignment
(T
);
10875 Set_Is_Constrained
(T
);
10877 if not Is_OK_Static_Expression
(Mod_Expr
) then
10878 Flag_Non_Static_Expr
10879 ("non-static expression used for modular type bound!", Mod_Expr
);
10880 M_Val
:= 2 ** System_Max_Binary_Modulus_Power
;
10882 M_Val
:= Expr_Value
(Mod_Expr
);
10886 Error_Msg_N
("modulus value must be positive", Mod_Expr
);
10887 M_Val
:= 2 ** System_Max_Binary_Modulus_Power
;
10890 Set_Modulus
(T
, M_Val
);
10892 -- Create bounds for the modular type based on the modulus given in
10893 -- the type declaration and then analyze and resolve those bounds.
10895 Set_Scalar_Range
(T
,
10896 Make_Range
(Sloc
(Mod_Expr
),
10898 Make_Integer_Literal
(Sloc
(Mod_Expr
), 0),
10900 Make_Integer_Literal
(Sloc
(Mod_Expr
), M_Val
- 1)));
10902 -- Properly analyze the literals for the range. We do this manually
10903 -- because we can't go calling Resolve, since we are resolving these
10904 -- bounds with the type, and this type is certainly not complete yet!
10906 Set_Etype
(Low_Bound
(Scalar_Range
(T
)), T
);
10907 Set_Etype
(High_Bound
(Scalar_Range
(T
)), T
);
10908 Set_Is_Static_Expression
(Low_Bound
(Scalar_Range
(T
)));
10909 Set_Is_Static_Expression
(High_Bound
(Scalar_Range
(T
)));
10911 -- Loop through powers of two to find number of bits required
10913 for Bits
in Int
range 0 .. System_Max_Binary_Modulus_Power
loop
10917 if M_Val
= 2 ** Bits
then
10918 Set_Modular_Size
(Bits
);
10923 elsif M_Val
< 2 ** Bits
then
10924 Set_Non_Binary_Modulus
(T
);
10926 if Bits
> System_Max_Nonbinary_Modulus_Power
then
10927 Error_Msg_Uint_1
:=
10928 UI_From_Int
(System_Max_Nonbinary_Modulus_Power
);
10930 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr
);
10931 Set_Modular_Size
(System_Max_Binary_Modulus_Power
);
10935 -- In the non-binary case, set size as per RM 13.3(55).
10937 Set_Modular_Size
(Bits
);
10944 -- If we fall through, then the size exceed System.Max_Binary_Modulus
10945 -- so we just signal an error and set the maximum size.
10947 Error_Msg_Uint_1
:= UI_From_Int
(System_Max_Binary_Modulus_Power
);
10948 Error_Msg_N
("modulus exceeds limit (2 '*'*^)", Mod_Expr
);
10950 Set_Modular_Size
(System_Max_Binary_Modulus_Power
);
10951 Init_Alignment
(T
);
10953 end Modular_Type_Declaration
;
10955 --------------------------
10956 -- New_Concatenation_Op --
10957 --------------------------
10959 procedure New_Concatenation_Op
(Typ
: Entity_Id
) is
10960 Loc
: constant Source_Ptr
:= Sloc
(Typ
);
10963 function Make_Op_Formal
(Typ
, Op
: Entity_Id
) return Entity_Id
;
10964 -- Create abbreviated declaration for the formal of a predefined
10965 -- Operator 'Op' of type 'Typ'
10967 --------------------
10968 -- Make_Op_Formal --
10969 --------------------
10971 function Make_Op_Formal
(Typ
, Op
: Entity_Id
) return Entity_Id
is
10972 Formal
: Entity_Id
;
10975 Formal
:= New_Internal_Entity
(E_In_Parameter
, Op
, Loc
, 'P');
10976 Set_Etype
(Formal
, Typ
);
10977 Set_Mechanism
(Formal
, Default_Mechanism
);
10979 end Make_Op_Formal
;
10981 -- Start of processing for New_Concatenation_Op
10984 Op
:= Make_Defining_Operator_Symbol
(Loc
, Name_Op_Concat
);
10986 Set_Ekind
(Op
, E_Operator
);
10987 Set_Scope
(Op
, Current_Scope
);
10988 Set_Etype
(Op
, Typ
);
10989 Set_Homonym
(Op
, Get_Name_Entity_Id
(Name_Op_Concat
));
10990 Set_Is_Immediately_Visible
(Op
);
10991 Set_Is_Intrinsic_Subprogram
(Op
);
10992 Set_Has_Completion
(Op
);
10993 Append_Entity
(Op
, Current_Scope
);
10995 Set_Name_Entity_Id
(Name_Op_Concat
, Op
);
10997 Append_Entity
(Make_Op_Formal
(Typ
, Op
), Op
);
10998 Append_Entity
(Make_Op_Formal
(Typ
, Op
), Op
);
11000 end New_Concatenation_Op
;
11002 -------------------------------------------
11003 -- Ordinary_Fixed_Point_Type_Declaration --
11004 -------------------------------------------
11006 procedure Ordinary_Fixed_Point_Type_Declaration
11010 Loc
: constant Source_Ptr
:= Sloc
(Def
);
11011 Delta_Expr
: constant Node_Id
:= Delta_Expression
(Def
);
11012 RRS
: constant Node_Id
:= Real_Range_Specification
(Def
);
11013 Implicit_Base
: Entity_Id
;
11020 Check_Restriction
(No_Fixed_Point
, Def
);
11022 -- Create implicit base type
11025 Create_Itype
(E_Ordinary_Fixed_Point_Type
, Parent
(Def
), T
, 'B');
11026 Set_Etype
(Implicit_Base
, Implicit_Base
);
11028 -- Analyze and process delta expression
11030 Analyze_And_Resolve
(Delta_Expr
, Any_Real
);
11032 Check_Delta_Expression
(Delta_Expr
);
11033 Delta_Val
:= Expr_Value_R
(Delta_Expr
);
11035 Set_Delta_Value
(Implicit_Base
, Delta_Val
);
11037 -- Compute default small from given delta, which is the largest
11038 -- power of two that does not exceed the given delta value.
11041 Tmp
: Ureal
:= Ureal_1
;
11045 if Delta_Val
< Ureal_1
then
11046 while Delta_Val
< Tmp
loop
11047 Tmp
:= Tmp
/ Ureal_2
;
11048 Scale
:= Scale
+ 1;
11053 Tmp
:= Tmp
* Ureal_2
;
11054 exit when Tmp
> Delta_Val
;
11055 Scale
:= Scale
- 1;
11059 Small_Val
:= UR_From_Components
(Uint_1
, UI_From_Int
(Scale
), 2);
11062 Set_Small_Value
(Implicit_Base
, Small_Val
);
11064 -- If no range was given, set a dummy range
11066 if RRS
<= Empty_Or_Error
then
11067 Low_Val
:= -Small_Val
;
11068 High_Val
:= Small_Val
;
11070 -- Otherwise analyze and process given range
11074 Low
: constant Node_Id
:= Low_Bound
(RRS
);
11075 High
: constant Node_Id
:= High_Bound
(RRS
);
11078 Analyze_And_Resolve
(Low
, Any_Real
);
11079 Analyze_And_Resolve
(High
, Any_Real
);
11080 Check_Real_Bound
(Low
);
11081 Check_Real_Bound
(High
);
11083 -- Obtain and set the range
11085 Low_Val
:= Expr_Value_R
(Low
);
11086 High_Val
:= Expr_Value_R
(High
);
11088 if Low_Val
> High_Val
then
11089 Error_Msg_NE
("?fixed point type& has null range", Def
, T
);
11094 -- The range for both the implicit base and the declared first
11095 -- subtype cannot be set yet, so we use the special routine
11096 -- Set_Fixed_Range to set a temporary range in place. Note that
11097 -- the bounds of the base type will be widened to be symmetrical
11098 -- and to fill the available bits when the type is frozen.
11100 -- We could do this with all discrete types, and probably should, but
11101 -- we absolutely have to do it for fixed-point, since the end-points
11102 -- of the range and the size are determined by the small value, which
11103 -- could be reset before the freeze point.
11105 Set_Fixed_Range
(Implicit_Base
, Loc
, Low_Val
, High_Val
);
11106 Set_Fixed_Range
(T
, Loc
, Low_Val
, High_Val
);
11108 Init_Size_Align
(Implicit_Base
);
11110 -- Complete definition of first subtype
11112 Set_Ekind
(T
, E_Ordinary_Fixed_Point_Subtype
);
11113 Set_Etype
(T
, Implicit_Base
);
11114 Init_Size_Align
(T
);
11115 Set_First_Rep_Item
(T
, First_Rep_Item
(Implicit_Base
));
11116 Set_Small_Value
(T
, Small_Val
);
11117 Set_Delta_Value
(T
, Delta_Val
);
11118 Set_Is_Constrained
(T
);
11120 end Ordinary_Fixed_Point_Type_Declaration
;
11122 ----------------------------------------
11123 -- Prepare_Private_Subtype_Completion --
11124 ----------------------------------------
11126 procedure Prepare_Private_Subtype_Completion
11128 Related_Nod
: Node_Id
)
11130 Id_B
: constant Entity_Id
:= Base_Type
(Id
);
11131 Full_B
: constant Entity_Id
:= Full_View
(Id_B
);
11135 if Present
(Full_B
) then
11137 -- The Base_Type is already completed, we can complete the
11138 -- subtype now. We have to create a new entity with the same name,
11139 -- Thus we can't use Create_Itype.
11140 -- This is messy, should be fixed ???
11142 Full
:= Make_Defining_Identifier
(Sloc
(Id
), Chars
(Id
));
11143 Set_Is_Itype
(Full
);
11144 Set_Associated_Node_For_Itype
(Full
, Related_Nod
);
11145 Complete_Private_Subtype
(Id
, Full
, Full_B
, Related_Nod
);
11148 -- The parent subtype may be private, but the base might not, in some
11149 -- nested instances. In that case, the subtype does not need to be
11150 -- exchanged. It would still be nice to make private subtypes and their
11151 -- bases consistent at all times ???
11153 if Is_Private_Type
(Id_B
) then
11154 Append_Elmt
(Id
, Private_Dependents
(Id_B
));
11157 end Prepare_Private_Subtype_Completion
;
11159 ---------------------------
11160 -- Process_Discriminants --
11161 ---------------------------
11163 procedure Process_Discriminants
11165 Prev
: Entity_Id
:= Empty
)
11167 Elist
: constant Elist_Id
:= New_Elmt_List
;
11170 Discr_Number
: Uint
;
11171 Discr_Type
: Entity_Id
;
11172 Default_Present
: Boolean := False;
11173 Default_Not_Present
: Boolean := False;
11176 -- A composite type other than an array type can have discriminants.
11177 -- Discriminants of non-limited types must have a discrete type.
11178 -- On entry, the current scope is the composite type.
11180 -- The discriminants are initially entered into the scope of the type
11181 -- via Enter_Name with the default Ekind of E_Void to prevent premature
11182 -- use, as explained at the end of this procedure.
11184 Discr
:= First
(Discriminant_Specifications
(N
));
11185 while Present
(Discr
) loop
11186 Enter_Name
(Defining_Identifier
(Discr
));
11188 -- For navigation purposes we add a reference to the discriminant
11189 -- in the entity for the type. If the current declaration is a
11190 -- completion, place references on the partial view. Otherwise the
11191 -- type is the current scope.
11193 if Present
(Prev
) then
11195 -- The references go on the partial view, if present. If the
11196 -- partial view has discriminants, the references have been
11197 -- generated already.
11199 if not Has_Discriminants
(Prev
) then
11200 Generate_Reference
(Prev
, Defining_Identifier
(Discr
), 'd');
11204 (Current_Scope
, Defining_Identifier
(Discr
), 'd');
11207 if Nkind
(Discriminant_Type
(Discr
)) = N_Access_Definition
then
11208 Discr_Type
:= Access_Definition
(N
, Discriminant_Type
(Discr
));
11211 Find_Type
(Discriminant_Type
(Discr
));
11212 Discr_Type
:= Etype
(Discriminant_Type
(Discr
));
11214 if Error_Posted
(Discriminant_Type
(Discr
)) then
11215 Discr_Type
:= Any_Type
;
11219 if Is_Access_Type
(Discr_Type
) then
11220 Check_Access_Discriminant_Requires_Limited
11221 (Discr
, Discriminant_Type
(Discr
));
11223 if Ada_83
and then Comes_From_Source
(Discr
) then
11225 ("(Ada 83) access discriminant not allowed", Discr
);
11228 elsif not Is_Discrete_Type
(Discr_Type
) then
11229 Error_Msg_N
("discriminants must have a discrete or access type",
11230 Discriminant_Type
(Discr
));
11233 Set_Etype
(Defining_Identifier
(Discr
), Discr_Type
);
11235 -- If a discriminant specification includes the assignment compound
11236 -- delimiter followed by an expression, the expression is the default
11237 -- expression of the discriminant; the default expression must be of
11238 -- the type of the discriminant. (RM 3.7.1) Since this expression is
11239 -- a default expression, we do the special preanalysis, since this
11240 -- expression does not freeze (see "Handling of Default and Per-
11241 -- Object Expressions" in spec of package Sem).
11243 if Present
(Expression
(Discr
)) then
11244 Analyze_Per_Use_Expression
(Expression
(Discr
), Discr_Type
);
11246 if Nkind
(N
) = N_Formal_Type_Declaration
then
11248 ("discriminant defaults not allowed for formal type",
11249 Expression
(Discr
));
11251 elsif Is_Tagged_Type
(Current_Scope
) then
11253 ("discriminants of tagged type cannot have defaults",
11254 Expression
(Discr
));
11257 Default_Present
:= True;
11258 Append_Elmt
(Expression
(Discr
), Elist
);
11260 -- Tag the defining identifiers for the discriminants with
11261 -- their corresponding default expressions from the tree.
11263 Set_Discriminant_Default_Value
11264 (Defining_Identifier
(Discr
), Expression
(Discr
));
11268 Default_Not_Present
:= True;
11274 -- An element list consisting of the default expressions of the
11275 -- discriminants is constructed in the above loop and used to set
11276 -- the Discriminant_Constraint attribute for the type. If an object
11277 -- is declared of this (record or task) type without any explicit
11278 -- discriminant constraint given, this element list will form the
11279 -- actual parameters for the corresponding initialization procedure
11282 Set_Discriminant_Constraint
(Current_Scope
, Elist
);
11283 Set_Stored_Constraint
(Current_Scope
, No_Elist
);
11285 -- Default expressions must be provided either for all or for none
11286 -- of the discriminants of a discriminant part. (RM 3.7.1)
11288 if Default_Present
and then Default_Not_Present
then
11290 ("incomplete specification of defaults for discriminants", N
);
11293 -- The use of the name of a discriminant is not allowed in default
11294 -- expressions of a discriminant part if the specification of the
11295 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
11297 -- To detect this, the discriminant names are entered initially with an
11298 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
11299 -- attempt to use a void entity (for example in an expression that is
11300 -- type-checked) produces the error message: premature usage. Now after
11301 -- completing the semantic analysis of the discriminant part, we can set
11302 -- the Ekind of all the discriminants appropriately.
11304 Discr
:= First
(Discriminant_Specifications
(N
));
11305 Discr_Number
:= Uint_1
;
11307 while Present
(Discr
) loop
11308 Id
:= Defining_Identifier
(Discr
);
11309 Set_Ekind
(Id
, E_Discriminant
);
11310 Init_Component_Location
(Id
);
11312 Set_Discriminant_Number
(Id
, Discr_Number
);
11314 -- Make sure this is always set, even in illegal programs
11316 Set_Corresponding_Discriminant
(Id
, Empty
);
11318 -- Initialize the Original_Record_Component to the entity itself.
11319 -- Inherit_Components will propagate the right value to
11320 -- discriminants in derived record types.
11322 Set_Original_Record_Component
(Id
, Id
);
11324 -- Create the discriminal for the discriminant.
11326 Build_Discriminal
(Id
);
11329 Discr_Number
:= Discr_Number
+ 1;
11332 Set_Has_Discriminants
(Current_Scope
);
11333 end Process_Discriminants
;
11335 -----------------------
11336 -- Process_Full_View --
11337 -----------------------
11339 procedure Process_Full_View
(N
: Node_Id
; Full_T
, Priv_T
: Entity_Id
) is
11340 Priv_Parent
: Entity_Id
;
11341 Full_Parent
: Entity_Id
;
11342 Full_Indic
: Node_Id
;
11345 -- First some sanity checks that must be done after semantic
11346 -- decoration of the full view and thus cannot be placed with other
11347 -- similar checks in Find_Type_Name
11349 if not Is_Limited_Type
(Priv_T
)
11350 and then (Is_Limited_Type
(Full_T
)
11351 or else Is_Limited_Composite
(Full_T
))
11354 ("completion of nonlimited type cannot be limited", Full_T
);
11355 Explain_Limited_Type
(Full_T
, Full_T
);
11357 elsif Is_Abstract
(Full_T
) and then not Is_Abstract
(Priv_T
) then
11359 ("completion of nonabstract type cannot be abstract", Full_T
);
11361 elsif Is_Tagged_Type
(Priv_T
)
11362 and then Is_Limited_Type
(Priv_T
)
11363 and then not Is_Limited_Type
(Full_T
)
11365 -- GNAT allow its own definition of Limited_Controlled to disobey
11366 -- this rule in order in ease the implementation. The next test is
11367 -- safe because Root_Controlled is defined in a private system child
11369 if Etype
(Full_T
) = Full_View
(RTE
(RE_Root_Controlled
)) then
11370 Set_Is_Limited_Composite
(Full_T
);
11373 ("completion of limited tagged type must be limited", Full_T
);
11376 elsif Is_Generic_Type
(Priv_T
) then
11377 Error_Msg_N
("generic type cannot have a completion", Full_T
);
11380 if Is_Tagged_Type
(Priv_T
)
11381 and then Nkind
(Parent
(Priv_T
)) = N_Private_Extension_Declaration
11382 and then Is_Derived_Type
(Full_T
)
11384 Priv_Parent
:= Etype
(Priv_T
);
11386 -- The full view of a private extension may have been transformed
11387 -- into an unconstrained derived type declaration and a subtype
11388 -- declaration (see build_derived_record_type for details).
11390 if Nkind
(N
) = N_Subtype_Declaration
then
11391 Full_Indic
:= Subtype_Indication
(N
);
11392 Full_Parent
:= Etype
(Base_Type
(Full_T
));
11394 Full_Indic
:= Subtype_Indication
(Type_Definition
(N
));
11395 Full_Parent
:= Etype
(Full_T
);
11398 -- Check that the parent type of the full type is a descendant of
11399 -- the ancestor subtype given in the private extension. If either
11400 -- entity has an Etype equal to Any_Type then we had some previous
11401 -- error situation [7.3(8)].
11403 if Priv_Parent
= Any_Type
or else Full_Parent
= Any_Type
then
11406 elsif not Is_Ancestor
(Base_Type
(Priv_Parent
), Full_Parent
) then
11408 ("parent of full type must descend from parent"
11409 & " of private extension", Full_Indic
);
11411 -- Check the rules of 7.3(10): if the private extension inherits
11412 -- known discriminants, then the full type must also inherit those
11413 -- discriminants from the same (ancestor) type, and the parent
11414 -- subtype of the full type must be constrained if and only if
11415 -- the ancestor subtype of the private extension is constrained.
11417 elsif not Present
(Discriminant_Specifications
(Parent
(Priv_T
)))
11418 and then not Has_Unknown_Discriminants
(Priv_T
)
11419 and then Has_Discriminants
(Base_Type
(Priv_Parent
))
11422 Priv_Indic
: constant Node_Id
:=
11423 Subtype_Indication
(Parent
(Priv_T
));
11425 Priv_Constr
: constant Boolean :=
11426 Is_Constrained
(Priv_Parent
)
11428 Nkind
(Priv_Indic
) = N_Subtype_Indication
11429 or else Is_Constrained
(Entity
(Priv_Indic
));
11431 Full_Constr
: constant Boolean :=
11432 Is_Constrained
(Full_Parent
)
11434 Nkind
(Full_Indic
) = N_Subtype_Indication
11435 or else Is_Constrained
(Entity
(Full_Indic
));
11437 Priv_Discr
: Entity_Id
;
11438 Full_Discr
: Entity_Id
;
11441 Priv_Discr
:= First_Discriminant
(Priv_Parent
);
11442 Full_Discr
:= First_Discriminant
(Full_Parent
);
11444 while Present
(Priv_Discr
) and then Present
(Full_Discr
) loop
11445 if Original_Record_Component
(Priv_Discr
) =
11446 Original_Record_Component
(Full_Discr
)
11448 Corresponding_Discriminant
(Priv_Discr
) =
11449 Corresponding_Discriminant
(Full_Discr
)
11456 Next_Discriminant
(Priv_Discr
);
11457 Next_Discriminant
(Full_Discr
);
11460 if Present
(Priv_Discr
) or else Present
(Full_Discr
) then
11462 ("full view must inherit discriminants of the parent type"
11463 & " used in the private extension", Full_Indic
);
11465 elsif Priv_Constr
and then not Full_Constr
then
11467 ("parent subtype of full type must be constrained",
11470 elsif Full_Constr
and then not Priv_Constr
then
11472 ("parent subtype of full type must be unconstrained",
11477 -- Check the rules of 7.3(12): if a partial view has neither known
11478 -- or unknown discriminants, then the full type declaration shall
11479 -- define a definite subtype.
11481 elsif not Has_Unknown_Discriminants
(Priv_T
)
11482 and then not Has_Discriminants
(Priv_T
)
11483 and then not Is_Constrained
(Full_T
)
11486 ("full view must define a constrained type if partial view"
11487 & " has no discriminants", Full_T
);
11490 -- ??????? Do we implement the following properly ?????
11491 -- If the ancestor subtype of a private extension has constrained
11492 -- discriminants, then the parent subtype of the full view shall
11493 -- impose a statically matching constraint on those discriminants
11497 -- For untagged types, verify that a type without discriminants
11498 -- is not completed with an unconstrained type.
11500 if not Is_Indefinite_Subtype
(Priv_T
)
11501 and then Is_Indefinite_Subtype
(Full_T
)
11503 Error_Msg_N
("full view of type must be definite subtype", Full_T
);
11507 -- Create a full declaration for all its subtypes recorded in
11508 -- Private_Dependents and swap them similarly to the base type.
11509 -- These are subtypes that have been define before the full
11510 -- declaration of the private type. We also swap the entry in
11511 -- Private_Dependents list so we can properly restore the
11512 -- private view on exit from the scope.
11515 Priv_Elmt
: Elmt_Id
;
11520 Priv_Elmt
:= First_Elmt
(Private_Dependents
(Priv_T
));
11521 while Present
(Priv_Elmt
) loop
11522 Priv
:= Node
(Priv_Elmt
);
11524 if Ekind
(Priv
) = E_Private_Subtype
11525 or else Ekind
(Priv
) = E_Limited_Private_Subtype
11526 or else Ekind
(Priv
) = E_Record_Subtype_With_Private
11528 Full
:= Make_Defining_Identifier
(Sloc
(Priv
), Chars
(Priv
));
11529 Set_Is_Itype
(Full
);
11530 Set_Parent
(Full
, Parent
(Priv
));
11531 Set_Associated_Node_For_Itype
(Full
, N
);
11533 -- Now we need to complete the private subtype, but since the
11534 -- base type has already been swapped, we must also swap the
11535 -- subtypes (and thus, reverse the arguments in the call to
11536 -- Complete_Private_Subtype).
11538 Copy_And_Swap
(Priv
, Full
);
11539 Complete_Private_Subtype
(Full
, Priv
, Full_T
, N
);
11540 Replace_Elmt
(Priv_Elmt
, Full
);
11543 Next_Elmt
(Priv_Elmt
);
11547 -- If the private view was tagged, copy the new Primitive
11548 -- operations from the private view to the full view.
11550 if Is_Tagged_Type
(Full_T
) then
11552 Priv_List
: Elist_Id
;
11553 Full_List
: constant Elist_Id
:= Primitive_Operations
(Full_T
);
11556 D_Type
: Entity_Id
;
11559 if Is_Tagged_Type
(Priv_T
) then
11560 Priv_List
:= Primitive_Operations
(Priv_T
);
11562 P1
:= First_Elmt
(Priv_List
);
11563 while Present
(P1
) loop
11566 -- Transfer explicit primitives, not those inherited from
11567 -- parent of partial view, which will be re-inherited on
11570 if Comes_From_Source
(Prim
) then
11571 P2
:= First_Elmt
(Full_List
);
11572 while Present
(P2
) and then Node
(P2
) /= Prim
loop
11576 -- If not found, that is a new one
11579 Append_Elmt
(Prim
, Full_List
);
11587 -- In this case the partial view is untagged, so here we
11588 -- locate all of the earlier primitives that need to be
11589 -- treated as dispatching (those that appear between the
11590 -- two views). Note that these additional operations must
11591 -- all be new operations (any earlier operations that
11592 -- override inherited operations of the full view will
11593 -- already have been inserted in the primitives list and
11594 -- marked as dispatching by Check_Operation_From_Private_View.
11595 -- Note that implicit "/=" operators are excluded from being
11596 -- added to the primitives list since they shouldn't be
11597 -- treated as dispatching (tagged "/=" is handled specially).
11599 Prim
:= Next_Entity
(Full_T
);
11600 while Present
(Prim
) and then Prim
/= Priv_T
loop
11601 if Ekind
(Prim
) = E_Procedure
11603 Ekind
(Prim
) = E_Function
11606 D_Type
:= Find_Dispatching_Type
(Prim
);
11609 and then (Chars
(Prim
) /= Name_Op_Ne
11610 or else Comes_From_Source
(Prim
))
11612 Check_Controlling_Formals
(Full_T
, Prim
);
11614 if not Is_Dispatching_Operation
(Prim
) then
11615 Append_Elmt
(Prim
, Full_List
);
11616 Set_Is_Dispatching_Operation
(Prim
, True);
11617 Set_DT_Position
(Prim
, No_Uint
);
11620 elsif Is_Dispatching_Operation
(Prim
)
11621 and then D_Type
/= Full_T
11624 -- Verify that it is not otherwise controlled by
11625 -- a formal or a return value ot type T.
11627 Check_Controlling_Formals
(D_Type
, Prim
);
11631 Next_Entity
(Prim
);
11635 -- For the tagged case, the two views can share the same
11636 -- Primitive Operation list and the same class wide type.
11637 -- Update attributes of the class-wide type which depend on
11638 -- the full declaration.
11640 if Is_Tagged_Type
(Priv_T
) then
11641 Set_Primitive_Operations
(Priv_T
, Full_List
);
11642 Set_Class_Wide_Type
11643 (Base_Type
(Full_T
), Class_Wide_Type
(Priv_T
));
11645 -- Any other attributes should be propagated to C_W ???
11647 Set_Has_Task
(Class_Wide_Type
(Priv_T
), Has_Task
(Full_T
));
11652 end Process_Full_View
;
11654 -----------------------------------
11655 -- Process_Incomplete_Dependents --
11656 -----------------------------------
11658 procedure Process_Incomplete_Dependents
11660 Full_T
: Entity_Id
;
11663 Inc_Elmt
: Elmt_Id
;
11664 Priv_Dep
: Entity_Id
;
11665 New_Subt
: Entity_Id
;
11667 Disc_Constraint
: Elist_Id
;
11670 if No
(Private_Dependents
(Inc_T
)) then
11674 Inc_Elmt
:= First_Elmt
(Private_Dependents
(Inc_T
));
11676 -- Itypes that may be generated by the completion of an incomplete
11677 -- subtype are not used by the back-end and not attached to the tree.
11678 -- They are created only for constraint-checking purposes.
11681 while Present
(Inc_Elmt
) loop
11682 Priv_Dep
:= Node
(Inc_Elmt
);
11684 if Ekind
(Priv_Dep
) = E_Subprogram_Type
then
11686 -- An Access_To_Subprogram type may have a return type or a
11687 -- parameter type that is incomplete. Replace with the full view.
11689 if Etype
(Priv_Dep
) = Inc_T
then
11690 Set_Etype
(Priv_Dep
, Full_T
);
11694 Formal
: Entity_Id
;
11697 Formal
:= First_Formal
(Priv_Dep
);
11699 while Present
(Formal
) loop
11701 if Etype
(Formal
) = Inc_T
then
11702 Set_Etype
(Formal
, Full_T
);
11705 Next_Formal
(Formal
);
11709 elsif Is_Overloadable
(Priv_Dep
) then
11711 if Is_Tagged_Type
(Full_T
) then
11713 -- Subprogram has an access parameter whose designated type
11714 -- was incomplete. Reexamine declaration now, because it may
11715 -- be a primitive operation of the full type.
11717 Check_Operation_From_Incomplete_Type
(Priv_Dep
, Inc_T
);
11718 Set_Is_Dispatching_Operation
(Priv_Dep
);
11719 Check_Controlling_Formals
(Full_T
, Priv_Dep
);
11722 elsif Ekind
(Priv_Dep
) = E_Subprogram_Body
then
11724 -- Can happen during processing of a body before the completion
11725 -- of a TA type. Ignore, because spec is also on dependent list.
11729 -- Dependent is a subtype
11732 -- We build a new subtype indication using the full view of the
11733 -- incomplete parent. The discriminant constraints have been
11734 -- elaborated already at the point of the subtype declaration.
11736 New_Subt
:= Create_Itype
(E_Void
, N
);
11738 if Has_Discriminants
(Full_T
) then
11739 Disc_Constraint
:= Discriminant_Constraint
(Priv_Dep
);
11741 Disc_Constraint
:= No_Elist
;
11744 Build_Discriminated_Subtype
(Full_T
, New_Subt
, Disc_Constraint
, N
);
11745 Set_Full_View
(Priv_Dep
, New_Subt
);
11748 Next_Elmt
(Inc_Elmt
);
11751 end Process_Incomplete_Dependents
;
11753 --------------------------------
11754 -- Process_Range_Expr_In_Decl --
11755 --------------------------------
11757 procedure Process_Range_Expr_In_Decl
11760 Check_List
: List_Id
:= Empty_List
;
11761 R_Check_Off
: Boolean := False)
11764 R_Checks
: Check_Result
;
11765 Type_Decl
: Node_Id
;
11766 Def_Id
: Entity_Id
;
11769 Analyze_And_Resolve
(R
, Base_Type
(T
));
11771 if Nkind
(R
) = N_Range
then
11772 Lo
:= Low_Bound
(R
);
11773 Hi
:= High_Bound
(R
);
11775 -- If there were errors in the declaration, try and patch up some
11776 -- common mistakes in the bounds. The cases handled are literals
11777 -- which are Integer where the expected type is Real and vice versa.
11778 -- These corrections allow the compilation process to proceed further
11779 -- along since some basic assumptions of the format of the bounds
11782 if Etype
(R
) = Any_Type
then
11784 if Nkind
(Lo
) = N_Integer_Literal
and then Is_Real_Type
(T
) then
11786 Make_Real_Literal
(Sloc
(Lo
), UR_From_Uint
(Intval
(Lo
))));
11788 elsif Nkind
(Hi
) = N_Integer_Literal
and then Is_Real_Type
(T
) then
11790 Make_Real_Literal
(Sloc
(Hi
), UR_From_Uint
(Intval
(Hi
))));
11792 elsif Nkind
(Lo
) = N_Real_Literal
and then Is_Integer_Type
(T
) then
11794 Make_Integer_Literal
(Sloc
(Lo
), UR_To_Uint
(Realval
(Lo
))));
11796 elsif Nkind
(Hi
) = N_Real_Literal
and then Is_Integer_Type
(T
) then
11798 Make_Integer_Literal
(Sloc
(Hi
), UR_To_Uint
(Realval
(Hi
))));
11805 -- If the bounds of the range have been mistakenly given as
11806 -- string literals (perhaps in place of character literals),
11807 -- then an error has already been reported, but we rewrite
11808 -- the string literal as a bound of the range's type to
11809 -- avoid blowups in later processing that looks at static
11812 if Nkind
(Lo
) = N_String_Literal
then
11814 Make_Attribute_Reference
(Sloc
(Lo
),
11815 Attribute_Name
=> Name_First
,
11816 Prefix
=> New_Reference_To
(T
, Sloc
(Lo
))));
11817 Analyze_And_Resolve
(Lo
);
11820 if Nkind
(Hi
) = N_String_Literal
then
11822 Make_Attribute_Reference
(Sloc
(Hi
),
11823 Attribute_Name
=> Name_First
,
11824 Prefix
=> New_Reference_To
(T
, Sloc
(Hi
))));
11825 Analyze_And_Resolve
(Hi
);
11828 -- If bounds aren't scalar at this point then exit, avoiding
11829 -- problems with further processing of the range in this procedure.
11831 if not Is_Scalar_Type
(Etype
(Lo
)) then
11835 -- Resolve (actually Sem_Eval) has checked that the bounds are in
11836 -- then range of the base type. Here we check whether the bounds
11837 -- are in the range of the subtype itself. Note that if the bounds
11838 -- represent the null range the Constraint_Error exception should
11841 -- ??? The following code should be cleaned up as follows
11842 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
11843 -- is done in the call to Range_Check (R, T); below
11844 -- 2. The use of R_Check_Off should be investigated and possibly
11845 -- removed, this would clean up things a bit.
11847 if Is_Null_Range
(Lo
, Hi
) then
11851 -- Capture values of bounds and generate temporaries for them
11852 -- if needed, before applying checks, since checks may cause
11853 -- duplication of the expression without forcing evaluation.
11855 if Expander_Active
then
11856 Force_Evaluation
(Lo
);
11857 Force_Evaluation
(Hi
);
11860 -- We use a flag here instead of suppressing checks on the
11861 -- type because the type we check against isn't necessarily
11862 -- the place where we put the check.
11864 if not R_Check_Off
then
11865 R_Checks
:= Range_Check
(R
, T
);
11866 Type_Decl
:= Parent
(R
);
11868 -- Look up tree to find an appropriate insertion point.
11869 -- This seems really junk code, and very brittle, couldn't
11870 -- we just use an insert actions call of some kind ???
11872 while Present
(Type_Decl
) and then not
11873 (Nkind
(Type_Decl
) = N_Full_Type_Declaration
11875 Nkind
(Type_Decl
) = N_Subtype_Declaration
11877 Nkind
(Type_Decl
) = N_Loop_Statement
11879 Nkind
(Type_Decl
) = N_Task_Type_Declaration
11881 Nkind
(Type_Decl
) = N_Single_Task_Declaration
11883 Nkind
(Type_Decl
) = N_Protected_Type_Declaration
11885 Nkind
(Type_Decl
) = N_Single_Protected_Declaration
)
11887 Type_Decl
:= Parent
(Type_Decl
);
11890 -- Why would Type_Decl not be present??? Without this test,
11891 -- short regression tests fail.
11893 if Present
(Type_Decl
) then
11895 -- Case of loop statement (more comments ???)
11897 if Nkind
(Type_Decl
) = N_Loop_Statement
then
11899 Indic
: Node_Id
:= Parent
(R
);
11902 while Present
(Indic
) and then not
11903 (Nkind
(Indic
) = N_Subtype_Indication
)
11905 Indic
:= Parent
(Indic
);
11908 if Present
(Indic
) then
11909 Def_Id
:= Etype
(Subtype_Mark
(Indic
));
11911 Insert_Range_Checks
11917 Do_Before
=> True);
11921 -- All other cases (more comments ???)
11924 Def_Id
:= Defining_Identifier
(Type_Decl
);
11926 if (Ekind
(Def_Id
) = E_Record_Type
11927 and then Depends_On_Discriminant
(R
))
11929 (Ekind
(Def_Id
) = E_Protected_Type
11930 and then Has_Discriminants
(Def_Id
))
11932 Append_Range_Checks
11933 (R_Checks
, Check_List
, Def_Id
, Sloc
(Type_Decl
), R
);
11936 Insert_Range_Checks
11937 (R_Checks
, Type_Decl
, Def_Id
, Sloc
(Type_Decl
), R
);
11945 elsif Expander_Active
then
11946 Get_Index_Bounds
(R
, Lo
, Hi
);
11947 Force_Evaluation
(Lo
);
11948 Force_Evaluation
(Hi
);
11950 end Process_Range_Expr_In_Decl
;
11952 --------------------------------------
11953 -- Process_Real_Range_Specification --
11954 --------------------------------------
11956 procedure Process_Real_Range_Specification
(Def
: Node_Id
) is
11957 Spec
: constant Node_Id
:= Real_Range_Specification
(Def
);
11960 Err
: Boolean := False;
11962 procedure Analyze_Bound
(N
: Node_Id
);
11963 -- Analyze and check one bound
11965 -------------------
11966 -- Analyze_Bound --
11967 -------------------
11969 procedure Analyze_Bound
(N
: Node_Id
) is
11971 Analyze_And_Resolve
(N
, Any_Real
);
11973 if not Is_OK_Static_Expression
(N
) then
11974 Flag_Non_Static_Expr
11975 ("bound in real type definition is not static!", N
);
11980 -- Start of processing for Process_Real_Range_Specification
11983 if Present
(Spec
) then
11984 Lo
:= Low_Bound
(Spec
);
11985 Hi
:= High_Bound
(Spec
);
11986 Analyze_Bound
(Lo
);
11987 Analyze_Bound
(Hi
);
11989 -- If error, clear away junk range specification
11992 Set_Real_Range_Specification
(Def
, Empty
);
11995 end Process_Real_Range_Specification
;
11997 ---------------------
11998 -- Process_Subtype --
11999 ---------------------
12001 function Process_Subtype
12003 Related_Nod
: Node_Id
;
12004 Related_Id
: Entity_Id
:= Empty
;
12005 Suffix
: Character := ' ') return Entity_Id
12008 Def_Id
: Entity_Id
;
12009 Full_View_Id
: Entity_Id
;
12010 Subtype_Mark_Id
: Entity_Id
;
12012 procedure Check_Incomplete
(T
: Entity_Id
);
12013 -- Called to verify that an incomplete type is not used prematurely
12015 ----------------------
12016 -- Check_Incomplete --
12017 ----------------------
12019 procedure Check_Incomplete
(T
: Entity_Id
) is
12021 if Ekind
(Root_Type
(Entity
(T
))) = E_Incomplete_Type
then
12022 Error_Msg_N
("invalid use of type before its full declaration", T
);
12024 end Check_Incomplete
;
12026 -- Start of processing for Process_Subtype
12029 -- Case of no constraints present
12031 if Nkind
(S
) /= N_Subtype_Indication
then
12034 Check_Incomplete
(S
);
12037 -- Case of constraint present, so that we have an N_Subtype_Indication
12038 -- node (this node is created only if constraints are present).
12042 Find_Type
(Subtype_Mark
(S
));
12044 if Nkind
(Parent
(S
)) /= N_Access_To_Object_Definition
12046 (Nkind
(Parent
(S
)) = N_Subtype_Declaration
12048 Is_Itype
(Defining_Identifier
(Parent
(S
))))
12050 Check_Incomplete
(Subtype_Mark
(S
));
12054 Subtype_Mark_Id
:= Entity
(Subtype_Mark
(S
));
12056 if Is_Unchecked_Union
(Subtype_Mark_Id
)
12057 and then Comes_From_Source
(Related_Nod
)
12060 ("cannot create subtype of Unchecked_Union", Related_Nod
);
12063 -- Explicit subtype declaration case
12065 if Nkind
(P
) = N_Subtype_Declaration
then
12066 Def_Id
:= Defining_Identifier
(P
);
12068 -- Explicit derived type definition case
12070 elsif Nkind
(P
) = N_Derived_Type_Definition
then
12071 Def_Id
:= Defining_Identifier
(Parent
(P
));
12073 -- Implicit case, the Def_Id must be created as an implicit type.
12074 -- The one exception arises in the case of concurrent types,
12075 -- array and access types, where other subsidiary implicit types
12076 -- may be created and must appear before the main implicit type.
12077 -- In these cases we leave Def_Id set to Empty as a signal that
12078 -- Create_Itype has not yet been called to create Def_Id.
12081 if Is_Array_Type
(Subtype_Mark_Id
)
12082 or else Is_Concurrent_Type
(Subtype_Mark_Id
)
12083 or else Is_Access_Type
(Subtype_Mark_Id
)
12087 -- For the other cases, we create a new unattached Itype,
12088 -- and set the indication to ensure it gets attached later.
12092 Create_Itype
(E_Void
, Related_Nod
, Related_Id
, Suffix
);
12096 -- If the kind of constraint is invalid for this kind of type,
12097 -- then give an error, and then pretend no constraint was given.
12099 if not Is_Valid_Constraint_Kind
12100 (Ekind
(Subtype_Mark_Id
), Nkind
(Constraint
(S
)))
12103 ("incorrect constraint for this kind of type", Constraint
(S
));
12105 Rewrite
(S
, New_Copy_Tree
(Subtype_Mark
(S
)));
12107 -- Make recursive call, having got rid of the bogus constraint
12109 return Process_Subtype
(S
, Related_Nod
, Related_Id
, Suffix
);
12112 -- Remaining processing depends on type
12114 case Ekind
(Subtype_Mark_Id
) is
12116 when Access_Kind
=>
12117 Constrain_Access
(Def_Id
, S
, Related_Nod
);
12120 Constrain_Array
(Def_Id
, S
, Related_Nod
, Related_Id
, Suffix
);
12122 when Decimal_Fixed_Point_Kind
=>
12123 Constrain_Decimal
(Def_Id
, S
);
12125 when Enumeration_Kind
=>
12126 Constrain_Enumeration
(Def_Id
, S
);
12128 when Ordinary_Fixed_Point_Kind
=>
12129 Constrain_Ordinary_Fixed
(Def_Id
, S
);
12132 Constrain_Float
(Def_Id
, S
);
12134 when Integer_Kind
=>
12135 Constrain_Integer
(Def_Id
, S
);
12137 when E_Record_Type |
12140 E_Incomplete_Type
=>
12141 Constrain_Discriminated_Type
(Def_Id
, S
, Related_Nod
);
12143 when Private_Kind
=>
12144 Constrain_Discriminated_Type
(Def_Id
, S
, Related_Nod
);
12145 Set_Private_Dependents
(Def_Id
, New_Elmt_List
);
12147 -- In case of an invalid constraint prevent further processing
12148 -- since the type constructed is missing expected fields.
12150 if Etype
(Def_Id
) = Any_Type
then
12154 -- If the full view is that of a task with discriminants,
12155 -- we must constrain both the concurrent type and its
12156 -- corresponding record type. Otherwise we will just propagate
12157 -- the constraint to the full view, if available.
12159 if Present
(Full_View
(Subtype_Mark_Id
))
12160 and then Has_Discriminants
(Subtype_Mark_Id
)
12161 and then Is_Concurrent_Type
(Full_View
(Subtype_Mark_Id
))
12164 Create_Itype
(E_Void
, Related_Nod
, Related_Id
, Suffix
);
12166 Set_Entity
(Subtype_Mark
(S
), Full_View
(Subtype_Mark_Id
));
12167 Constrain_Concurrent
(Full_View_Id
, S
,
12168 Related_Nod
, Related_Id
, Suffix
);
12169 Set_Entity
(Subtype_Mark
(S
), Subtype_Mark_Id
);
12170 Set_Full_View
(Def_Id
, Full_View_Id
);
12173 Prepare_Private_Subtype_Completion
(Def_Id
, Related_Nod
);
12176 when Concurrent_Kind
=>
12177 Constrain_Concurrent
(Def_Id
, S
,
12178 Related_Nod
, Related_Id
, Suffix
);
12181 Error_Msg_N
("invalid subtype mark in subtype indication", S
);
12184 -- Size and Convention are always inherited from the base type
12186 Set_Size_Info
(Def_Id
, (Subtype_Mark_Id
));
12187 Set_Convention
(Def_Id
, Convention
(Subtype_Mark_Id
));
12192 end Process_Subtype
;
12194 -----------------------------
12195 -- Record_Type_Declaration --
12196 -----------------------------
12198 procedure Record_Type_Declaration
12203 Def
: constant Node_Id
:= Type_Definition
(N
);
12205 Is_Tagged
: Boolean;
12206 Tag_Comp
: Entity_Id
;
12209 -- The flag Is_Tagged_Type might have already been set by Find_Type_Name
12210 -- if it detected an error for declaration T. This arises in the case of
12211 -- private tagged types where the full view omits the word tagged.
12213 Is_Tagged
:= Tagged_Present
(Def
)
12214 or else (Serious_Errors_Detected
> 0 and then Is_Tagged_Type
(T
));
12216 -- Records constitute a scope for the component declarations within.
12217 -- The scope is created prior to the processing of these declarations.
12218 -- Discriminants are processed first, so that they are visible when
12219 -- processing the other components. The Ekind of the record type itself
12220 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
12222 -- Enter record scope
12226 -- These flags must be initialized before calling Process_Discriminants
12227 -- because this routine makes use of them.
12229 Set_Is_Tagged_Type
(T
, Is_Tagged
);
12230 Set_Is_Limited_Record
(T
, Limited_Present
(Def
));
12232 -- Type is abstract if full declaration carries keyword, or if
12233 -- previous partial view did.
12235 Set_Is_Abstract
(T
, Is_Abstract
(T
) or else Abstract_Present
(Def
));
12237 Set_Ekind
(T
, E_Record_Type
);
12239 Init_Size_Align
(T
);
12241 Set_Stored_Constraint
(T
, No_Elist
);
12243 -- If an incomplete or private type declaration was already given for
12244 -- the type, then this scope already exists, and the discriminants have
12245 -- been declared within. We must verify that the full declaration
12246 -- matches the incomplete one.
12248 Check_Or_Process_Discriminants
(N
, T
, Prev
);
12250 Set_Is_Constrained
(T
, not Has_Discriminants
(T
));
12251 Set_Has_Delayed_Freeze
(T
, True);
12253 -- For tagged types add a manually analyzed component corresponding
12254 -- to the component _tag, the corresponding piece of tree will be
12255 -- expanded as part of the freezing actions if it is not a CPP_Class.
12258 -- Do not add the tag unless we are in expansion mode.
12260 if Expander_Active
then
12261 Tag_Comp
:= Make_Defining_Identifier
(Sloc
(Def
), Name_uTag
);
12262 Enter_Name
(Tag_Comp
);
12264 Set_Is_Tag
(Tag_Comp
);
12265 Set_Ekind
(Tag_Comp
, E_Component
);
12266 Set_Etype
(Tag_Comp
, RTE
(RE_Tag
));
12267 Set_DT_Entry_Count
(Tag_Comp
, No_Uint
);
12268 Set_Original_Record_Component
(Tag_Comp
, Tag_Comp
);
12269 Init_Component_Location
(Tag_Comp
);
12272 Make_Class_Wide_Type
(T
);
12273 Set_Primitive_Operations
(T
, New_Elmt_List
);
12276 -- We must suppress range checks when processing the components
12277 -- of a record in the presence of discriminants, since we don't
12278 -- want spurious checks to be generated during their analysis, but
12279 -- must reset the Suppress_Range_Checks flags after having processed
12280 -- the record definition.
12282 if Has_Discriminants
(T
) and then not Range_Checks_Suppressed
(T
) then
12283 Set_Kill_Range_Checks
(T
, True);
12284 Record_Type_Definition
(Def
, Prev
);
12285 Set_Kill_Range_Checks
(T
, False);
12287 Record_Type_Definition
(Def
, Prev
);
12290 -- Exit from record scope
12293 end Record_Type_Declaration
;
12295 ----------------------------
12296 -- Record_Type_Definition --
12297 ----------------------------
12299 procedure Record_Type_Definition
(Def
: Node_Id
; Prev_T
: Entity_Id
) is
12300 Component
: Entity_Id
;
12301 Ctrl_Components
: Boolean := False;
12302 Final_Storage_Only
: Boolean;
12306 if Ekind
(Prev_T
) = E_Incomplete_Type
then
12307 T
:= Full_View
(Prev_T
);
12312 Final_Storage_Only
:= not Is_Controlled
(T
);
12314 -- If the component list of a record type is defined by the reserved
12315 -- word null and there is no discriminant part, then the record type has
12316 -- no components and all records of the type are null records (RM 3.7)
12317 -- This procedure is also called to process the extension part of a
12318 -- record extension, in which case the current scope may have inherited
12322 or else No
(Component_List
(Def
))
12323 or else Null_Present
(Component_List
(Def
))
12328 Analyze_Declarations
(Component_Items
(Component_List
(Def
)));
12330 if Present
(Variant_Part
(Component_List
(Def
))) then
12331 Analyze
(Variant_Part
(Component_List
(Def
)));
12335 -- After completing the semantic analysis of the record definition,
12336 -- record components, both new and inherited, are accessible. Set
12337 -- their kind accordingly.
12339 Component
:= First_Entity
(Current_Scope
);
12340 while Present
(Component
) loop
12342 if Ekind
(Component
) = E_Void
then
12343 Set_Ekind
(Component
, E_Component
);
12344 Init_Component_Location
(Component
);
12347 if Has_Task
(Etype
(Component
)) then
12351 if Ekind
(Component
) /= E_Component
then
12354 elsif Has_Controlled_Component
(Etype
(Component
))
12355 or else (Chars
(Component
) /= Name_uParent
12356 and then Is_Controlled
(Etype
(Component
)))
12358 Set_Has_Controlled_Component
(T
, True);
12359 Final_Storage_Only
:= Final_Storage_Only
12360 and then Finalize_Storage_Only
(Etype
(Component
));
12361 Ctrl_Components
:= True;
12364 Next_Entity
(Component
);
12367 -- A type is Finalize_Storage_Only only if all its controlled
12368 -- components are so.
12370 if Ctrl_Components
then
12371 Set_Finalize_Storage_Only
(T
, Final_Storage_Only
);
12374 -- Place reference to end record on the proper entity, which may
12375 -- be a partial view.
12377 if Present
(Def
) then
12378 Process_End_Label
(Def
, 'e', Prev_T
);
12380 end Record_Type_Definition
;
12382 ------------------------
12383 -- Replace_Components --
12384 ------------------------
12386 procedure Replace_Components
(Typ
: Entity_Id
; Decl
: Node_Id
) is
12387 function Process
(N
: Node_Id
) return Traverse_Result
;
12393 function Process
(N
: Node_Id
) return Traverse_Result
is
12397 if Nkind
(N
) = N_Discriminant_Specification
then
12398 Comp
:= First_Discriminant
(Typ
);
12400 while Present
(Comp
) loop
12401 if Chars
(Comp
) = Chars
(Defining_Identifier
(N
)) then
12402 Set_Defining_Identifier
(N
, Comp
);
12406 Next_Discriminant
(Comp
);
12409 elsif Nkind
(N
) = N_Component_Declaration
then
12410 Comp
:= First_Component
(Typ
);
12412 while Present
(Comp
) loop
12413 if Chars
(Comp
) = Chars
(Defining_Identifier
(N
)) then
12414 Set_Defining_Identifier
(N
, Comp
);
12418 Next_Component
(Comp
);
12425 procedure Replace
is new Traverse_Proc
(Process
);
12427 -- Start of processing for Replace_Components
12431 end Replace_Components
;
12433 -------------------------------
12434 -- Set_Completion_Referenced --
12435 -------------------------------
12437 procedure Set_Completion_Referenced
(E
: Entity_Id
) is
12439 -- If in main unit, mark entity that is a completion as referenced,
12440 -- warnings go on the partial view when needed.
12442 if In_Extended_Main_Source_Unit
(E
) then
12443 Set_Referenced
(E
);
12445 end Set_Completion_Referenced
;
12447 ---------------------
12448 -- Set_Fixed_Range --
12449 ---------------------
12451 -- The range for fixed-point types is complicated by the fact that we
12452 -- do not know the exact end points at the time of the declaration. This
12453 -- is true for three reasons:
12455 -- A size clause may affect the fudging of the end-points
12456 -- A small clause may affect the values of the end-points
12457 -- We try to include the end-points if it does not affect the size
12459 -- This means that the actual end-points must be established at the
12460 -- point when the type is frozen. Meanwhile, we first narrow the range
12461 -- as permitted (so that it will fit if necessary in a small specified
12462 -- size), and then build a range subtree with these narrowed bounds.
12464 -- Set_Fixed_Range constructs the range from real literal values, and
12465 -- sets the range as the Scalar_Range of the given fixed-point type
12468 -- The parent of this range is set to point to the entity so that it
12469 -- is properly hooked into the tree (unlike normal Scalar_Range entries
12470 -- for other scalar types, which are just pointers to the range in the
12471 -- original tree, this would otherwise be an orphan).
12473 -- The tree is left unanalyzed. When the type is frozen, the processing
12474 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
12475 -- analyzed, and uses this as an indication that it should complete
12476 -- work on the range (it will know the final small and size values).
12478 procedure Set_Fixed_Range
12484 S
: constant Node_Id
:=
12486 Low_Bound
=> Make_Real_Literal
(Loc
, Lo
),
12487 High_Bound
=> Make_Real_Literal
(Loc
, Hi
));
12490 Set_Scalar_Range
(E
, S
);
12492 end Set_Fixed_Range
;
12494 ----------------------------------
12495 -- Set_Scalar_Range_For_Subtype --
12496 ----------------------------------
12498 procedure Set_Scalar_Range_For_Subtype
12499 (Def_Id
: Entity_Id
;
12503 Kind
: constant Entity_Kind
:= Ekind
(Def_Id
);
12505 Set_Scalar_Range
(Def_Id
, R
);
12507 -- We need to link the range into the tree before resolving it so
12508 -- that types that are referenced, including importantly the subtype
12509 -- itself, are properly frozen (Freeze_Expression requires that the
12510 -- expression be properly linked into the tree). Of course if it is
12511 -- already linked in, then we do not disturb the current link.
12513 if No
(Parent
(R
)) then
12514 Set_Parent
(R
, Def_Id
);
12517 -- Reset the kind of the subtype during analysis of the range, to
12518 -- catch possible premature use in the bounds themselves.
12520 Set_Ekind
(Def_Id
, E_Void
);
12521 Process_Range_Expr_In_Decl
(R
, Subt
);
12522 Set_Ekind
(Def_Id
, Kind
);
12524 end Set_Scalar_Range_For_Subtype
;
12526 --------------------------------------------------------
12527 -- Set_Stored_Constraint_From_Discriminant_Constraint --
12528 --------------------------------------------------------
12530 procedure Set_Stored_Constraint_From_Discriminant_Constraint
12534 -- Make sure set if encountered during
12535 -- Expand_To_Stored_Constraint
12537 Set_Stored_Constraint
(E
, No_Elist
);
12539 -- Give it the right value
12541 if Is_Constrained
(E
) and then Has_Discriminants
(E
) then
12542 Set_Stored_Constraint
(E
,
12543 Expand_To_Stored_Constraint
(E
, Discriminant_Constraint
(E
)));
12546 end Set_Stored_Constraint_From_Discriminant_Constraint
;
12548 -------------------------------------
12549 -- Signed_Integer_Type_Declaration --
12550 -------------------------------------
12552 procedure Signed_Integer_Type_Declaration
(T
: Entity_Id
; Def
: Node_Id
) is
12553 Implicit_Base
: Entity_Id
;
12554 Base_Typ
: Entity_Id
;
12557 Errs
: Boolean := False;
12561 function Can_Derive_From
(E
: Entity_Id
) return Boolean;
12562 -- Determine whether given bounds allow derivation from specified type
12564 procedure Check_Bound
(Expr
: Node_Id
);
12565 -- Check bound to make sure it is integral and static. If not, post
12566 -- appropriate error message and set Errs flag
12568 ---------------------
12569 -- Can_Derive_From --
12570 ---------------------
12572 function Can_Derive_From
(E
: Entity_Id
) return Boolean is
12573 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(E
));
12574 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(E
));
12577 -- Note we check both bounds against both end values, to deal with
12578 -- strange types like ones with a range of 0 .. -12341234.
12580 return Lo
<= Lo_Val
and then Lo_Val
<= Hi
12582 Lo
<= Hi_Val
and then Hi_Val
<= Hi
;
12583 end Can_Derive_From
;
12589 procedure Check_Bound
(Expr
: Node_Id
) is
12591 -- If a range constraint is used as an integer type definition, each
12592 -- bound of the range must be defined by a static expression of some
12593 -- integer type, but the two bounds need not have the same integer
12594 -- type (Negative bounds are allowed.) (RM 3.5.4)
12596 if not Is_Integer_Type
(Etype
(Expr
)) then
12598 ("integer type definition bounds must be of integer type", Expr
);
12601 elsif not Is_OK_Static_Expression
(Expr
) then
12602 Flag_Non_Static_Expr
12603 ("non-static expression used for integer type bound!", Expr
);
12606 -- The bounds are folded into literals, and we set their type to be
12607 -- universal, to avoid typing difficulties: we cannot set the type
12608 -- of the literal to the new type, because this would be a forward
12609 -- reference for the back end, and if the original type is user-
12610 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
12613 if Is_Entity_Name
(Expr
) then
12614 Fold_Uint
(Expr
, Expr_Value
(Expr
), True);
12617 Set_Etype
(Expr
, Universal_Integer
);
12621 -- Start of processing for Signed_Integer_Type_Declaration
12624 -- Create an anonymous base type
12627 Create_Itype
(E_Signed_Integer_Type
, Parent
(Def
), T
, 'B');
12629 -- Analyze and check the bounds, they can be of any integer type
12631 Lo
:= Low_Bound
(Def
);
12632 Hi
:= High_Bound
(Def
);
12634 -- Arbitrarily use Integer as the type if either bound had an error
12636 if Hi
= Error
or else Lo
= Error
then
12637 Base_Typ
:= Any_Integer
;
12638 Set_Error_Posted
(T
, True);
12640 -- Here both bounds are OK expressions
12643 Analyze_And_Resolve
(Lo
, Any_Integer
);
12644 Analyze_And_Resolve
(Hi
, Any_Integer
);
12650 Hi
:= Type_High_Bound
(Standard_Long_Long_Integer
);
12651 Lo
:= Type_Low_Bound
(Standard_Long_Long_Integer
);
12654 -- Find type to derive from
12656 Lo_Val
:= Expr_Value
(Lo
);
12657 Hi_Val
:= Expr_Value
(Hi
);
12659 if Can_Derive_From
(Standard_Short_Short_Integer
) then
12660 Base_Typ
:= Base_Type
(Standard_Short_Short_Integer
);
12662 elsif Can_Derive_From
(Standard_Short_Integer
) then
12663 Base_Typ
:= Base_Type
(Standard_Short_Integer
);
12665 elsif Can_Derive_From
(Standard_Integer
) then
12666 Base_Typ
:= Base_Type
(Standard_Integer
);
12668 elsif Can_Derive_From
(Standard_Long_Integer
) then
12669 Base_Typ
:= Base_Type
(Standard_Long_Integer
);
12671 elsif Can_Derive_From
(Standard_Long_Long_Integer
) then
12672 Base_Typ
:= Base_Type
(Standard_Long_Long_Integer
);
12675 Base_Typ
:= Base_Type
(Standard_Long_Long_Integer
);
12676 Error_Msg_N
("integer type definition bounds out of range", Def
);
12677 Hi
:= Type_High_Bound
(Standard_Long_Long_Integer
);
12678 Lo
:= Type_Low_Bound
(Standard_Long_Long_Integer
);
12682 -- Complete both implicit base and declared first subtype entities
12684 Set_Etype
(Implicit_Base
, Base_Typ
);
12685 Set_Scalar_Range
(Implicit_Base
, Scalar_Range
(Base_Typ
));
12686 Set_Size_Info
(Implicit_Base
, (Base_Typ
));
12687 Set_RM_Size
(Implicit_Base
, RM_Size
(Base_Typ
));
12688 Set_First_Rep_Item
(Implicit_Base
, First_Rep_Item
(Base_Typ
));
12690 Set_Ekind
(T
, E_Signed_Integer_Subtype
);
12691 Set_Etype
(T
, Implicit_Base
);
12693 Set_Size_Info
(T
, (Implicit_Base
));
12694 Set_First_Rep_Item
(T
, First_Rep_Item
(Implicit_Base
));
12695 Set_Scalar_Range
(T
, Def
);
12696 Set_RM_Size
(T
, UI_From_Int
(Minimum_Size
(T
)));
12697 Set_Is_Constrained
(T
);
12698 end Signed_Integer_Type_Declaration
;