1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Disp
; use Exp_Disp
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Fname
; use Fname
;
35 with Freeze
; use Freeze
;
36 with Ghost
; use Ghost
;
37 with Impunit
; use Impunit
;
39 with Lib
.Load
; use Lib
.Load
;
40 with Lib
.Xref
; use Lib
.Xref
;
41 with Namet
; use Namet
;
42 with Namet
.Sp
; use Namet
.Sp
;
43 with Nlists
; use Nlists
;
44 with Nmake
; use Nmake
;
46 with Output
; use Output
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
51 with Sem_Aux
; use Sem_Aux
;
52 with Sem_Cat
; use Sem_Cat
;
53 with Sem_Ch3
; use Sem_Ch3
;
54 with Sem_Ch4
; use Sem_Ch4
;
55 with Sem_Ch6
; use Sem_Ch6
;
56 with Sem_Ch12
; use Sem_Ch12
;
57 with Sem_Ch13
; use Sem_Ch13
;
58 with Sem_Dim
; use Sem_Dim
;
59 with Sem_Disp
; use Sem_Disp
;
60 with Sem_Dist
; use Sem_Dist
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Res
; use Sem_Res
;
63 with Sem_Util
; use Sem_Util
;
64 with Sem_Type
; use Sem_Type
;
65 with Stand
; use Stand
;
66 with Sinfo
; use Sinfo
;
67 with Sinfo
.CN
; use Sinfo
.CN
;
68 with Snames
; use Snames
;
69 with Style
; use Style
;
71 with Targparm
; use Targparm
;
72 with Tbuild
; use Tbuild
;
73 with Uintp
; use Uintp
;
75 package body Sem_Ch8
is
77 ------------------------------------
78 -- Visibility and Name Resolution --
79 ------------------------------------
81 -- This package handles name resolution and the collection of possible
82 -- interpretations for overloaded names, prior to overload resolution.
84 -- Name resolution is the process that establishes a mapping between source
85 -- identifiers and the entities they denote at each point in the program.
86 -- Each entity is represented by a defining occurrence. Each identifier
87 -- that denotes an entity points to the corresponding defining occurrence.
88 -- This is the entity of the applied occurrence. Each occurrence holds
89 -- an index into the names table, where source identifiers are stored.
91 -- Each entry in the names table for an identifier or designator uses the
92 -- Info pointer to hold a link to the currently visible entity that has
93 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
94 -- in package Sem_Util). The visibility is initialized at the beginning of
95 -- semantic processing to make entities in package Standard immediately
96 -- visible. The visibility table is used in a more subtle way when
97 -- compiling subunits (see below).
99 -- Entities that have the same name (i.e. homonyms) are chained. In the
100 -- case of overloaded entities, this chain holds all the possible meanings
101 -- of a given identifier. The process of overload resolution uses type
102 -- information to select from this chain the unique meaning of a given
105 -- Entities are also chained in their scope, through the Next_Entity link.
106 -- As a consequence, the name space is organized as a sparse matrix, where
107 -- each row corresponds to a scope, and each column to a source identifier.
108 -- Open scopes, that is to say scopes currently being compiled, have their
109 -- corresponding rows of entities in order, innermost scope first.
111 -- The scopes of packages that are mentioned in context clauses appear in
112 -- no particular order, interspersed among open scopes. This is because
113 -- in the course of analyzing the context of a compilation, a package
114 -- declaration is first an open scope, and subsequently an element of the
115 -- context. If subunits or child units are present, a parent unit may
116 -- appear under various guises at various times in the compilation.
118 -- When the compilation of the innermost scope is complete, the entities
119 -- defined therein are no longer visible. If the scope is not a package
120 -- declaration, these entities are never visible subsequently, and can be
121 -- removed from visibility chains. If the scope is a package declaration,
122 -- its visible declarations may still be accessible. Therefore the entities
123 -- defined in such a scope are left on the visibility chains, and only
124 -- their visibility (immediately visibility or potential use-visibility)
127 -- The ordering of homonyms on their chain does not necessarily follow
128 -- the order of their corresponding scopes on the scope stack. For
129 -- example, if package P and the enclosing scope both contain entities
130 -- named E, then when compiling the package body the chain for E will
131 -- hold the global entity first, and the local one (corresponding to
132 -- the current inner scope) next. As a result, name resolution routines
133 -- do not assume any relative ordering of the homonym chains, either
134 -- for scope nesting or to order of appearance of context clauses.
136 -- When compiling a child unit, entities in the parent scope are always
137 -- immediately visible. When compiling the body of a child unit, private
138 -- entities in the parent must also be made immediately visible. There
139 -- are separate routines to make the visible and private declarations
140 -- visible at various times (see package Sem_Ch7).
142 -- +--------+ +-----+
143 -- | In use |-------->| EU1 |-------------------------->
144 -- +--------+ +-----+
146 -- +--------+ +-----+ +-----+
147 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
148 -- +--------+ +-----+ +-----+
150 -- +---------+ | +-----+
151 -- | with'ed |------------------------------>| EW2 |--->
152 -- +---------+ | +-----+
154 -- +--------+ +-----+ +-----+
155 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
156 -- +--------+ +-----+ +-----+
158 -- +--------+ +-----+ +-----+
159 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
160 -- +--------+ +-----+ +-----+
164 -- | | with'ed |----------------------------------------->
168 -- (innermost first) | |
169 -- +----------------------------+
170 -- Names table => | Id1 | | | | Id2 |
171 -- +----------------------------+
173 -- Name resolution must deal with several syntactic forms: simple names,
174 -- qualified names, indexed names, and various forms of calls.
176 -- Each identifier points to an entry in the names table. The resolution
177 -- of a simple name consists in traversing the homonym chain, starting
178 -- from the names table. If an entry is immediately visible, it is the one
179 -- designated by the identifier. If only potentially use-visible entities
180 -- are on the chain, we must verify that they do not hide each other. If
181 -- the entity we find is overloadable, we collect all other overloadable
182 -- entities on the chain as long as they are not hidden.
184 -- To resolve expanded names, we must find the entity at the intersection
185 -- of the entity chain for the scope (the prefix) and the homonym chain
186 -- for the selector. In general, homonym chains will be much shorter than
187 -- entity chains, so it is preferable to start from the names table as
188 -- well. If the entity found is overloadable, we must collect all other
189 -- interpretations that are defined in the scope denoted by the prefix.
191 -- For records, protected types, and tasks, their local entities are
192 -- removed from visibility chains on exit from the corresponding scope.
193 -- From the outside, these entities are always accessed by selected
194 -- notation, and the entity chain for the record type, protected type,
195 -- etc. is traversed sequentially in order to find the designated entity.
197 -- The discriminants of a type and the operations of a protected type or
198 -- task are unchained on exit from the first view of the type, (such as
199 -- a private or incomplete type declaration, or a protected type speci-
200 -- fication) and re-chained when compiling the second view.
202 -- In the case of operators, we do not make operators on derived types
203 -- explicit. As a result, the notation P."+" may denote either a user-
204 -- defined function with name "+", or else an implicit declaration of the
205 -- operator "+" in package P. The resolution of expanded names always
206 -- tries to resolve an operator name as such an implicitly defined entity,
207 -- in addition to looking for explicit declarations.
209 -- All forms of names that denote entities (simple names, expanded names,
210 -- character literals in some cases) have a Entity attribute, which
211 -- identifies the entity denoted by the name.
213 ---------------------
214 -- The Scope Stack --
215 ---------------------
217 -- The Scope stack keeps track of the scopes currently been compiled.
218 -- Every entity that contains declarations (including records) is placed
219 -- on the scope stack while it is being processed, and removed at the end.
220 -- Whenever a non-package scope is exited, the entities defined therein
221 -- are removed from the visibility table, so that entities in outer scopes
222 -- become visible (see previous description). On entry to Sem, the scope
223 -- stack only contains the package Standard. As usual, subunits complicate
224 -- this picture ever so slightly.
226 -- The Rtsfind mechanism can force a call to Semantics while another
227 -- compilation is in progress. The unit retrieved by Rtsfind must be
228 -- compiled in its own context, and has no access to the visibility of
229 -- the unit currently being compiled. The procedures Save_Scope_Stack and
230 -- Restore_Scope_Stack make entities in current open scopes invisible
231 -- before compiling the retrieved unit, and restore the compilation
232 -- environment afterwards.
234 ------------------------
235 -- Compiling subunits --
236 ------------------------
238 -- Subunits must be compiled in the environment of the corresponding stub,
239 -- that is to say with the same visibility into the parent (and its
240 -- context) that is available at the point of the stub declaration, but
241 -- with the additional visibility provided by the context clause of the
242 -- subunit itself. As a result, compilation of a subunit forces compilation
243 -- of the parent (see description in lib-). At the point of the stub
244 -- declaration, Analyze is called recursively to compile the proper body of
245 -- the subunit, but without reinitializing the names table, nor the scope
246 -- stack (i.e. standard is not pushed on the stack). In this fashion the
247 -- context of the subunit is added to the context of the parent, and the
248 -- subunit is compiled in the correct environment. Note that in the course
249 -- of processing the context of a subunit, Standard will appear twice on
250 -- the scope stack: once for the parent of the subunit, and once for the
251 -- unit in the context clause being compiled. However, the two sets of
252 -- entities are not linked by homonym chains, so that the compilation of
253 -- any context unit happens in a fresh visibility environment.
255 -------------------------------
256 -- Processing of USE Clauses --
257 -------------------------------
259 -- Every defining occurrence has a flag indicating if it is potentially use
260 -- visible. Resolution of simple names examines this flag. The processing
261 -- of use clauses consists in setting this flag on all visible entities
262 -- defined in the corresponding package. On exit from the scope of the use
263 -- clause, the corresponding flag must be reset. However, a package may
264 -- appear in several nested use clauses (pathological but legal, alas)
265 -- which forces us to use a slightly more involved scheme:
267 -- a) The defining occurrence for a package holds a flag -In_Use- to
268 -- indicate that it is currently in the scope of a use clause. If a
269 -- redundant use clause is encountered, then the corresponding occurrence
270 -- of the package name is flagged -Redundant_Use-.
272 -- b) On exit from a scope, the use clauses in its declarative part are
273 -- scanned. The visibility flag is reset in all entities declared in
274 -- package named in a use clause, as long as the package is not flagged
275 -- as being in a redundant use clause (in which case the outer use
276 -- clause is still in effect, and the direct visibility of its entities
277 -- must be retained).
279 -- Note that entities are not removed from their homonym chains on exit
280 -- from the package specification. A subsequent use clause does not need
281 -- to rechain the visible entities, but only to establish their direct
284 -----------------------------------
285 -- Handling private declarations --
286 -----------------------------------
288 -- The principle that each entity has a single defining occurrence clashes
289 -- with the presence of two separate definitions for private types: the
290 -- first is the private type declaration, and second is the full type
291 -- declaration. It is important that all references to the type point to
292 -- the same defining occurrence, namely the first one. To enforce the two
293 -- separate views of the entity, the corresponding information is swapped
294 -- between the two declarations. Outside of the package, the defining
295 -- occurrence only contains the private declaration information, while in
296 -- the private part and the body of the package the defining occurrence
297 -- contains the full declaration. To simplify the swap, the defining
298 -- occurrence that currently holds the private declaration points to the
299 -- full declaration. During semantic processing the defining occurrence
300 -- also points to a list of private dependents, that is to say access types
301 -- or composite types whose designated types or component types are
302 -- subtypes or derived types of the private type in question. After the
303 -- full declaration has been seen, the private dependents are updated to
304 -- indicate that they have full definitions.
306 ------------------------------------
307 -- Handling of Undefined Messages --
308 ------------------------------------
310 -- In normal mode, only the first use of an undefined identifier generates
311 -- a message. The table Urefs is used to record error messages that have
312 -- been issued so that second and subsequent ones do not generate further
313 -- messages. However, the second reference causes text to be added to the
314 -- original undefined message noting "(more references follow)". The
315 -- full error list option (-gnatf) forces messages to be generated for
316 -- every reference and disconnects the use of this table.
318 type Uref_Entry
is record
320 -- Node for identifier for which original message was posted. The
321 -- Chars field of this identifier is used to detect later references
322 -- to the same identifier.
325 -- Records error message Id of original undefined message. Reset to
326 -- No_Error_Msg after the second occurrence, where it is used to add
327 -- text to the original message as described above.
330 -- Set if the message is not visible rather than undefined
333 -- Records location of error message. Used to make sure that we do
334 -- not consider a, b : undefined as two separate instances, which
335 -- would otherwise happen, since the parser converts this sequence
336 -- to a : undefined; b : undefined.
340 package Urefs
is new Table
.Table
(
341 Table_Component_Type
=> Uref_Entry
,
342 Table_Index_Type
=> Nat
,
343 Table_Low_Bound
=> 1,
345 Table_Increment
=> 100,
346 Table_Name
=> "Urefs");
348 Candidate_Renaming
: Entity_Id
;
349 -- Holds a candidate interpretation that appears in a subprogram renaming
350 -- declaration and does not match the given specification, but matches at
351 -- least on the first formal. Allows better error message when given
352 -- specification omits defaulted parameters, a common error.
354 -----------------------
355 -- Local Subprograms --
356 -----------------------
358 procedure Analyze_Generic_Renaming
361 -- Common processing for all three kinds of generic renaming declarations.
362 -- Enter new name and indicate that it renames the generic unit.
364 procedure Analyze_Renamed_Character
368 -- Renamed entity is given by a character literal, which must belong
369 -- to the return type of the new entity. Is_Body indicates whether the
370 -- declaration is a renaming_as_body. If the original declaration has
371 -- already been frozen (because of an intervening body, e.g.) the body of
372 -- the function must be built now. The same applies to the following
373 -- various renaming procedures.
375 procedure Analyze_Renamed_Dereference
379 -- Renamed entity is given by an explicit dereference. Prefix must be a
380 -- conformant access_to_subprogram type.
382 procedure Analyze_Renamed_Entry
386 -- If the renamed entity in a subprogram renaming is an entry or protected
387 -- subprogram, build a body for the new entity whose only statement is a
388 -- call to the renamed entity.
390 procedure Analyze_Renamed_Family_Member
394 -- Used when the renamed entity is an indexed component. The prefix must
395 -- denote an entry family.
397 procedure Analyze_Renamed_Primitive_Operation
401 -- If the renamed entity in a subprogram renaming is a primitive operation
402 -- or a class-wide operation in prefix form, save the target object,
403 -- which must be added to the list of actuals in any subsequent call.
404 -- The renaming operation is intrinsic because the compiler must in
405 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
407 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
408 -- Common code to Use_One_Package and Set_Use, to determine whether use
409 -- clause must be processed. Pack_Name is an entity name that references
410 -- the package in question.
412 procedure Attribute_Renaming
(N
: Node_Id
);
413 -- Analyze renaming of attribute as subprogram. The renaming declaration N
414 -- is rewritten as a subprogram body that returns the attribute reference
415 -- applied to the formals of the function.
417 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
418 -- Set Entity, with style check if need be. For a discriminant reference,
419 -- replace by the corresponding discriminal, i.e. the parameter of the
420 -- initialization procedure that corresponds to the discriminant.
422 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
423 -- A renaming_as_body may occur after the entity of the original decla-
424 -- ration has been frozen. In that case, the body of the new entity must
425 -- be built now, because the usual mechanism of building the renamed
426 -- body at the point of freezing will not work. Subp is the subprogram
427 -- for which N provides the Renaming_As_Body.
429 procedure Check_In_Previous_With_Clause
432 -- N is a use_package clause and Nam the package name, or N is a use_type
433 -- clause and Nam is the prefix of the type name. In either case, verify
434 -- that the package is visible at that point in the context: either it
435 -- appears in a previous with_clause, or because it is a fully qualified
436 -- name and the root ancestor appears in a previous with_clause.
438 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
439 -- Verify that the entity in a renaming declaration that is a library unit
440 -- is itself a library unit and not a nested unit or subunit. Also check
441 -- that if the renaming is a child unit of a generic parent, then the
442 -- renamed unit must also be a child unit of that parent. Finally, verify
443 -- that a renamed generic unit is not an implicit child declared within
444 -- an instance of the parent.
446 procedure Chain_Use_Clause
(N
: Node_Id
);
447 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
448 -- the proper scope table entry. This is usually the current scope, but it
449 -- will be an inner scope when installing the use clauses of the private
450 -- declarations of a parent unit prior to compiling the private part of a
451 -- child unit. This chain is traversed when installing/removing use clauses
452 -- when compiling a subunit or instantiating a generic body on the fly,
453 -- when it is necessary to save and restore full environments.
455 function Enclosing_Instance
return Entity_Id
;
456 -- In an instance nested within another one, several semantic checks are
457 -- unnecessary because the legality of the nested instance has been checked
458 -- in the enclosing generic unit. This applies in particular to legality
459 -- checks on actuals for formal subprograms of the inner instance, which
460 -- are checked as subprogram renamings, and may be complicated by confusion
461 -- in private/full views. This function returns the instance enclosing the
462 -- current one if there is such, else it returns Empty.
464 -- If the renaming determines the entity for the default of a formal
465 -- subprogram nested within another instance, choose the innermost
466 -- candidate. This is because if the formal has a box, and we are within
467 -- an enclosing instance where some candidate interpretations are local
468 -- to this enclosing instance, we know that the default was properly
469 -- resolved when analyzing the generic, so we prefer the local
470 -- candidates to those that are external. This is not always the case
471 -- but is a reasonable heuristic on the use of nested generics. The
472 -- proper solution requires a full renaming model.
474 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
475 -- Find a type derived from Character or Wide_Character in the prefix of N.
476 -- Used to resolved qualified names whose selector is a character literal.
478 function Has_Private_With
(E
: Entity_Id
) return Boolean;
479 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
480 -- private with on E.
482 procedure Find_Expanded_Name
(N
: Node_Id
);
483 -- The input is a selected component known to be an expanded name. Verify
484 -- legality of selector given the scope denoted by prefix, and change node
485 -- N into a expanded name with a properly set Entity field.
487 function Find_Renamed_Entity
491 Is_Actual
: Boolean := False) return Entity_Id
;
492 -- Find the renamed entity that corresponds to the given parameter profile
493 -- in a subprogram renaming declaration. The renamed entity may be an
494 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
495 -- indicates that the renaming is the one generated for an actual subpro-
496 -- gram in an instance, for which special visibility checks apply.
498 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
499 -- N is an expanded name whose selector is an operator name (e.g. P."+").
500 -- declarative part contains an implicit declaration of an operator if it
501 -- has a declaration of a type to which one of the predefined operators
502 -- apply. The existence of this routine is an implementation artifact. A
503 -- more straightforward but more space-consuming choice would be to make
504 -- all inherited operators explicit in the symbol table.
506 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
507 -- A subprogram defined by a renaming declaration inherits the parameter
508 -- profile of the renamed entity. The subtypes given in the subprogram
509 -- specification are discarded and replaced with those of the renamed
510 -- subprogram, which are then used to recheck the default values.
512 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
513 -- Prefix is appropriate for record if it is of a record type, or an access
516 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
517 -- True if it is of a task type, a protected type, or else an access to one
520 procedure Note_Redundant_Use
(Clause
: Node_Id
);
521 -- Mark the name in a use clause as redundant if the corresponding entity
522 -- is already use-visible. Emit a warning if the use clause comes from
523 -- source and the proper warnings are enabled.
525 procedure Premature_Usage
(N
: Node_Id
);
526 -- Diagnose usage of an entity before it is visible
528 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
529 -- Make visible entities declared in package P potentially use-visible
530 -- in the current context. Also used in the analysis of subunits, when
531 -- re-installing use clauses of parent units. N is the use_clause that
532 -- names P (and possibly other packages).
534 procedure Use_One_Type
(Id
: Node_Id
; Installed
: Boolean := False);
535 -- Id is the subtype mark from a use type clause. This procedure makes
536 -- the primitive operators of the type potentially use-visible. The
537 -- boolean flag Installed indicates that the clause is being reinstalled
538 -- after previous analysis, and primitive operations are already chained
539 -- on the Used_Operations list of the clause.
541 procedure Write_Info
;
542 -- Write debugging information on entities declared in current scope
544 --------------------------------
545 -- Analyze_Exception_Renaming --
546 --------------------------------
548 -- The language only allows a single identifier, but the tree holds an
549 -- identifier list. The parser has already issued an error message if
550 -- there is more than one element in the list.
552 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
553 Id
: constant Node_Id
:= Defining_Identifier
(N
);
554 Nam
: constant Node_Id
:= Name
(N
);
557 -- The exception renaming declaration may be subject to pragma Ghost
558 -- with policy Ignore. Set the mode now to ensure that any nodes
559 -- generated during analysis and expansion are properly flagged as
563 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
568 Set_Ekind
(Id
, E_Exception
);
569 Set_Etype
(Id
, Standard_Exception_Type
);
570 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
572 if not Is_Entity_Name
(Nam
)
573 or else Ekind
(Entity
(Nam
)) /= E_Exception
575 Error_Msg_N
("invalid exception name in renaming", Nam
);
577 if Present
(Renamed_Object
(Entity
(Nam
))) then
578 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
580 Set_Renamed_Object
(Id
, Entity
(Nam
));
583 -- An exception renaming is Ghost if the renamed entity is Ghost or
584 -- the construct appears within a Ghost scope.
586 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
587 Set_Is_Ghost_Entity
(Id
);
591 -- Implementation-defined aspect specifications can appear in a renaming
592 -- declaration, but not language-defined ones. The call to procedure
593 -- Analyze_Aspect_Specifications will take care of this error check.
595 if Has_Aspects
(N
) then
596 Analyze_Aspect_Specifications
(N
, Id
);
598 end Analyze_Exception_Renaming
;
600 ---------------------------
601 -- Analyze_Expanded_Name --
602 ---------------------------
604 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
606 -- If the entity pointer is already set, this is an internal node, or a
607 -- node that is analyzed more than once, after a tree modification. In
608 -- such a case there is no resolution to perform, just set the type. For
609 -- completeness, analyze prefix as well.
611 if Present
(Entity
(N
)) then
612 if Is_Type
(Entity
(N
)) then
613 Set_Etype
(N
, Entity
(N
));
615 Set_Etype
(N
, Etype
(Entity
(N
)));
618 Analyze
(Prefix
(N
));
621 Find_Expanded_Name
(N
);
624 Analyze_Dimension
(N
);
625 end Analyze_Expanded_Name
;
627 ---------------------------------------
628 -- Analyze_Generic_Function_Renaming --
629 ---------------------------------------
631 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
633 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
634 end Analyze_Generic_Function_Renaming
;
636 --------------------------------------
637 -- Analyze_Generic_Package_Renaming --
638 --------------------------------------
640 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
642 -- Test for the Text_IO special unit case here, since we may be renaming
643 -- one of the subpackages of Text_IO, then join common routine.
645 Check_Text_IO_Special_Unit
(Name
(N
));
647 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
648 end Analyze_Generic_Package_Renaming
;
650 ----------------------------------------
651 -- Analyze_Generic_Procedure_Renaming --
652 ----------------------------------------
654 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
656 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
657 end Analyze_Generic_Procedure_Renaming
;
659 ------------------------------
660 -- Analyze_Generic_Renaming --
661 ------------------------------
663 procedure Analyze_Generic_Renaming
667 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
669 Inst
: Boolean := False; -- prevent junk warning
672 if Name
(N
) = Error
then
676 -- The generic renaming declaration may be subject to pragma Ghost with
677 -- policy Ignore. Set the mode now to ensure that any nodes generated
678 -- during analysis and expansion are properly flagged as ignored Ghost.
681 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
683 Generate_Definition
(New_P
);
685 if Current_Scope
/= Standard_Standard
then
686 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
689 if Nkind
(Name
(N
)) = N_Selected_Component
then
690 Check_Generic_Child_Unit
(Name
(N
), Inst
);
695 if not Is_Entity_Name
(Name
(N
)) then
696 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
699 Old_P
:= Entity
(Name
(N
));
703 Set_Ekind
(New_P
, K
);
705 if Etype
(Old_P
) = Any_Type
then
708 elsif Ekind
(Old_P
) /= K
then
709 Error_Msg_N
("invalid generic unit name", Name
(N
));
712 if Present
(Renamed_Object
(Old_P
)) then
713 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
715 Set_Renamed_Object
(New_P
, Old_P
);
718 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
719 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
721 Set_Etype
(New_P
, Etype
(Old_P
));
722 Set_Has_Completion
(New_P
);
724 -- An generic renaming is Ghost if the renamed entity is Ghost or the
725 -- construct appears within a Ghost scope.
727 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
728 Set_Is_Ghost_Entity
(New_P
);
731 if In_Open_Scopes
(Old_P
) then
732 Error_Msg_N
("within its scope, generic denotes its instance", N
);
735 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
736 -- renamings and subsequent instantiations of Unchecked_Conversion.
738 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
739 Set_Is_Intrinsic_Subprogram
740 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
743 Check_Library_Unit_Renaming
(N
, Old_P
);
746 -- Implementation-defined aspect specifications can appear in a renaming
747 -- declaration, but not language-defined ones. The call to procedure
748 -- Analyze_Aspect_Specifications will take care of this error check.
750 if Has_Aspects
(N
) then
751 Analyze_Aspect_Specifications
(N
, New_P
);
753 end Analyze_Generic_Renaming
;
755 -----------------------------
756 -- Analyze_Object_Renaming --
757 -----------------------------
759 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
760 Loc
: constant Source_Ptr
:= Sloc
(N
);
761 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
763 Nam
: constant Node_Id
:= Name
(N
);
767 procedure Check_Constrained_Object
;
768 -- If the nominal type is unconstrained but the renamed object is
769 -- constrained, as can happen with renaming an explicit dereference or
770 -- a function return, build a constrained subtype from the object. If
771 -- the renaming is for a formal in an accept statement, the analysis
772 -- has already established its actual subtype. This is only relevant
773 -- if the renamed object is an explicit dereference.
775 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
776 -- Determine whether entity E is inside a generic cope
778 ------------------------------
779 -- Check_Constrained_Object --
780 ------------------------------
782 procedure Check_Constrained_Object
is
783 Typ
: constant Entity_Id
:= Etype
(Nam
);
787 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
788 and then Is_Composite_Type
(Etype
(Nam
))
789 and then not Is_Constrained
(Etype
(Nam
))
790 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
791 and then Expander_Active
793 -- If Actual_Subtype is already set, nothing to do
795 if Ekind_In
(Id
, E_Variable
, E_Constant
)
796 and then Present
(Actual_Subtype
(Id
))
800 -- A renaming of an unchecked union has no actual subtype
802 elsif Is_Unchecked_Union
(Typ
) then
805 -- If a record is limited its size is invariant. This is the case
806 -- in particular with record types with an access discirminant
807 -- that are used in iterators. This is an optimization, but it
808 -- also prevents typing anomalies when the prefix is further
809 -- expanded. Limited types with discriminants are included.
811 elsif Is_Limited_Record
(Typ
)
813 (Ekind
(Typ
) = E_Limited_Private_Type
814 and then Has_Discriminants
(Typ
)
815 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
820 Subt
:= Make_Temporary
(Loc
, 'T');
821 Remove_Side_Effects
(Nam
);
823 Make_Subtype_Declaration
(Loc
,
824 Defining_Identifier
=> Subt
,
825 Subtype_Indication
=>
826 Make_Subtype_From_Expr
(Nam
, Typ
)));
827 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
828 Set_Etype
(Nam
, Subt
);
830 -- Freeze subtype at once, to prevent order of elaboration
831 -- issues in the backend. The renamed object exists, so its
832 -- type is already frozen in any case.
834 Freeze_Before
(N
, Subt
);
837 end Check_Constrained_Object
;
839 ----------------------
840 -- In_Generic_Scope --
841 ----------------------
843 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
848 while Present
(S
) and then S
/= Standard_Standard
loop
849 if Is_Generic_Unit
(S
) then
857 end In_Generic_Scope
;
859 -- Start of processing for Analyze_Object_Renaming
866 -- The object renaming declaration may be subject to pragma Ghost with
867 -- policy Ignore. Set the mode now to ensure that any nodes generated
868 -- during analysis and expansion are properly flagged as ignored Ghost.
871 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
873 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
876 -- The renaming of a component that depends on a discriminant requires
877 -- an actual subtype, because in subsequent use of the object Gigi will
878 -- be unable to locate the actual bounds. This explicit step is required
879 -- when the renaming is generated in removing side effects of an
880 -- already-analyzed expression.
882 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
884 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
886 if Present
(Dec
) then
887 Insert_Action
(N
, Dec
);
888 T
:= Defining_Identifier
(Dec
);
892 -- Complete analysis of the subtype mark in any case, for ASIS use
894 if Present
(Subtype_Mark
(N
)) then
895 Find_Type
(Subtype_Mark
(N
));
898 elsif Present
(Subtype_Mark
(N
)) then
899 Find_Type
(Subtype_Mark
(N
));
900 T
:= Entity
(Subtype_Mark
(N
));
903 -- Reject renamings of conversions unless the type is tagged, or
904 -- the conversion is implicit (which can occur for cases of anonymous
905 -- access types in Ada 2012).
907 if Nkind
(Nam
) = N_Type_Conversion
908 and then Comes_From_Source
(Nam
)
909 and then not Is_Tagged_Type
(T
)
912 ("renaming of conversion only allowed for tagged types", Nam
);
915 -- Reject renaming of component of Volatile_Full_Access object
917 if Nkind_In
(Nam
, N_Selected_Component
, N_Indexed_Component
) then
919 P
: constant Node_Id
:= Prefix
(Nam
);
921 if Is_Entity_Name
(P
) then
922 if Is_Volatile_Full_Access
(Entity
(P
))
924 Is_Volatile_Full_Access
(Etype
(P
))
927 ("cannot rename component of Volatile_Full_Access "
936 -- If the renamed object is a function call of a limited type,
937 -- the expansion of the renaming is complicated by the presence
938 -- of various temporaries and subtypes that capture constraints
939 -- of the renamed object. Rewrite node as an object declaration,
940 -- whose expansion is simpler. Given that the object is limited
941 -- there is no copy involved and no performance hit.
943 if Nkind
(Nam
) = N_Function_Call
944 and then Is_Limited_View
(Etype
(Nam
))
945 and then not Is_Constrained
(Etype
(Nam
))
946 and then Comes_From_Source
(N
)
949 Set_Ekind
(Id
, E_Constant
);
951 Make_Object_Declaration
(Loc
,
952 Defining_Identifier
=> Id
,
953 Constant_Present
=> True,
954 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
955 Expression
=> Relocate_Node
(Nam
)));
959 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
960 -- when renaming declaration has a named access type. The Ada 2012
961 -- coverage rules allow an anonymous access type in the context of
962 -- an expected named general access type, but the renaming rules
963 -- require the types to be the same. (An exception is when the type
964 -- of the renaming is also an anonymous access type, which can only
965 -- happen due to a renaming created by the expander.)
967 if Nkind
(Nam
) = N_Type_Conversion
968 and then not Comes_From_Source
(Nam
)
969 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
970 and then Ekind
(T
) /= E_Anonymous_Access_Type
972 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
975 -- Check that a class-wide object is not being renamed as an object
976 -- of a specific type. The test for access types is needed to exclude
977 -- cases where the renamed object is a dynamically tagged access
978 -- result, such as occurs in certain expansions.
980 if Is_Tagged_Type
(T
) then
981 Check_Dynamically_Tagged_Expression
987 -- Ada 2005 (AI-230/AI-254): Access renaming
989 else pragma Assert
(Present
(Access_Definition
(N
)));
990 T
:= Access_Definition
992 N
=> Access_Definition
(N
));
996 -- Ada 2005 AI05-105: if the declaration has an anonymous access
997 -- type, the renamed object must also have an anonymous type, and
998 -- this is a name resolution rule. This was implicit in the last part
999 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
1002 if not Is_Overloaded
(Nam
) then
1003 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
1005 ("expect anonymous access type in object renaming", N
);
1012 Typ
: Entity_Id
:= Empty
;
1013 Seen
: Boolean := False;
1016 Get_First_Interp
(Nam
, I
, It
);
1017 while Present
(It
.Typ
) loop
1019 -- Renaming is ambiguous if more than one candidate
1020 -- interpretation is type-conformant with the context.
1022 if Ekind
(It
.Typ
) = Ekind
(T
) then
1023 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
1026 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
1032 ("ambiguous expression in renaming", Nam
);
1035 elsif Ekind
(T
) = E_Anonymous_Access_Type
1037 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1043 ("ambiguous expression in renaming", Nam
);
1047 if Covers
(T
, It
.Typ
) then
1049 Set_Etype
(Nam
, Typ
);
1050 Set_Is_Overloaded
(Nam
, False);
1054 Get_Next_Interp
(I
, It
);
1061 -- Ada 2005 (AI-231): In the case where the type is defined by an
1062 -- access_definition, the renamed entity shall be of an access-to-
1063 -- constant type if and only if the access_definition defines an
1064 -- access-to-constant type. ARM 8.5.1(4)
1066 if Constant_Present
(Access_Definition
(N
))
1067 and then not Is_Access_Constant
(Etype
(Nam
))
1069 Error_Msg_N
("(Ada 2005): the renamed object is not "
1070 & "access-to-constant (RM 8.5.1(6))", N
);
1072 elsif not Constant_Present
(Access_Definition
(N
))
1073 and then Is_Access_Constant
(Etype
(Nam
))
1075 Error_Msg_N
("(Ada 2005): the renamed object is not "
1076 & "access-to-variable (RM 8.5.1(6))", N
);
1079 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1080 Check_Subtype_Conformant
1081 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1083 elsif not Subtypes_Statically_Match
1084 (Designated_Type
(T
),
1085 Available_View
(Designated_Type
(Etype
(Nam
))))
1088 ("subtype of renamed object does not statically match", N
);
1092 -- Special processing for renaming function return object. Some errors
1093 -- and warnings are produced only for calls that come from source.
1095 if Nkind
(Nam
) = N_Function_Call
then
1098 -- Usage is illegal in Ada 83, but renamings are also introduced
1099 -- during expansion, and error does not apply to those.
1102 if Comes_From_Source
(N
) then
1104 ("(Ada 83) cannot rename function return object", Nam
);
1107 -- In Ada 95, warn for odd case of renaming parameterless function
1108 -- call if this is not a limited type (where this is useful).
1111 if Warn_On_Object_Renames_Function
1112 and then No
(Parameter_Associations
(Nam
))
1113 and then not Is_Limited_Type
(Etype
(Nam
))
1114 and then Comes_From_Source
(Nam
)
1117 ("renaming function result object is suspicious?R?", Nam
);
1119 ("\function & will be called only once?R?", Nam
,
1120 Entity
(Name
(Nam
)));
1121 Error_Msg_N
-- CODEFIX
1122 ("\suggest using an initialized constant "
1123 & "object instead?R?", Nam
);
1129 Check_Constrained_Object
;
1131 -- An object renaming requires an exact match of the type. Class-wide
1132 -- matching is not allowed.
1134 if Is_Class_Wide_Type
(T
)
1135 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1137 Wrong_Type
(Nam
, T
);
1142 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1144 if Nkind
(Nam
) = N_Explicit_Dereference
1145 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1147 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1150 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1151 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1155 -- Ada 2005 (AI-327)
1157 if Ada_Version
>= Ada_2005
1158 and then Nkind
(Nam
) = N_Attribute_Reference
1159 and then Attribute_Name
(Nam
) = Name_Priority
1163 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1166 Nam_Ent
: Entity_Id
;
1169 if Nkind
(Nam
) = N_Attribute_Reference
then
1170 Nam_Ent
:= Entity
(Prefix
(Nam
));
1172 Nam_Ent
:= Entity
(Nam
);
1175 Nam_Decl
:= Parent
(Nam_Ent
);
1177 if Has_Null_Exclusion
(N
)
1178 and then not Has_Null_Exclusion
(Nam_Decl
)
1180 -- Ada 2005 (AI-423): If the object name denotes a generic
1181 -- formal object of a generic unit G, and the object renaming
1182 -- declaration occurs within the body of G or within the body
1183 -- of a generic unit declared within the declarative region
1184 -- of G, then the declaration of the formal object of G must
1185 -- have a null exclusion or a null-excluding subtype.
1187 if Is_Formal_Object
(Nam_Ent
)
1188 and then In_Generic_Scope
(Id
)
1190 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1192 ("renamed formal does not exclude `NULL` "
1193 & "(RM 8.5.1(4.6/2))", N
);
1195 elsif In_Package_Body
(Scope
(Id
)) then
1197 ("formal object does not have a null exclusion"
1198 & "(RM 8.5.1(4.6/2))", N
);
1201 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1202 -- shall exclude null.
1204 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1206 ("renamed object does not exclude `NULL` "
1207 & "(RM 8.5.1(4.6/2))", N
);
1209 -- An instance is illegal if it contains a renaming that
1210 -- excludes null, and the actual does not. The renaming
1211 -- declaration has already indicated that the declaration
1212 -- of the renamed actual in the instance will raise
1213 -- constraint_error.
1215 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1216 and then In_Instance
1218 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1219 and then Nkind
(Expression
(Nam_Decl
)) =
1220 N_Raise_Constraint_Error
1223 ("renamed actual does not exclude `NULL` "
1224 & "(RM 8.5.1(4.6/2))", N
);
1226 -- Finally, if there is a null exclusion, the subtype mark
1227 -- must not be null-excluding.
1229 elsif No
(Access_Definition
(N
))
1230 and then Can_Never_Be_Null
(T
)
1233 ("`NOT NULL` not allowed (& already excludes null)",
1238 elsif Can_Never_Be_Null
(T
)
1239 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1242 ("renamed object does not exclude `NULL` "
1243 & "(RM 8.5.1(4.6/2))", N
);
1245 elsif Has_Null_Exclusion
(N
)
1246 and then No
(Access_Definition
(N
))
1247 and then Can_Never_Be_Null
(T
)
1250 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1255 -- Set the Ekind of the entity, unless it has been set already, as is
1256 -- the case for the iteration object over a container with no variable
1257 -- indexing. In that case it's been marked as a constant, and we do not
1258 -- want to change it to a variable.
1260 if Ekind
(Id
) /= E_Constant
then
1261 Set_Ekind
(Id
, E_Variable
);
1264 -- Initialize the object size and alignment. Note that we used to call
1265 -- Init_Size_Align here, but that's wrong for objects which have only
1266 -- an Esize, not an RM_Size field.
1268 Init_Object_Size_Align
(Id
);
1270 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1273 -- Verify that the renamed entity is an object or a function call. It
1274 -- may have been rewritten in several ways.
1276 elsif Is_Object_Reference
(Nam
) then
1277 if Comes_From_Source
(N
) then
1278 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1280 ("illegal renaming of discriminant-dependent component", Nam
);
1283 -- If the renaming comes from source and the renamed object is a
1284 -- dereference, then mark the prefix as needing debug information,
1285 -- since it might have been rewritten hence internally generated
1286 -- and Debug_Renaming_Declaration will link the renaming to it.
1288 if Nkind
(Nam
) = N_Explicit_Dereference
1289 and then Is_Entity_Name
(Prefix
(Nam
))
1291 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1295 -- A static function call may have been folded into a literal
1297 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1299 -- When expansion is disabled, attribute reference is not rewritten
1300 -- as function call. Otherwise it may be rewritten as a conversion,
1301 -- so check original node.
1303 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1304 and then Is_Function_Attribute_Name
1305 (Attribute_Name
(Original_Node
(Nam
))))
1307 -- Weird but legal, equivalent to renaming a function call. Illegal
1308 -- if the literal is the result of constant-folding an attribute
1309 -- reference that is not a function.
1311 or else (Is_Entity_Name
(Nam
)
1312 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1314 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1316 or else (Nkind
(Nam
) = N_Type_Conversion
1317 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1321 elsif Nkind
(Nam
) = N_Type_Conversion
then
1323 ("renaming of conversion only allowed for tagged types", Nam
);
1325 -- Ada 2005 (AI-327)
1327 elsif Ada_Version
>= Ada_2005
1328 and then Nkind
(Nam
) = N_Attribute_Reference
1329 and then Attribute_Name
(Nam
) = Name_Priority
1333 -- Allow internally generated x'Reference expression
1335 elsif Nkind
(Nam
) = N_Reference
then
1339 Error_Msg_N
("expect object name in renaming", Nam
);
1344 if not Is_Variable
(Nam
) then
1345 Set_Ekind
(Id
, E_Constant
);
1346 Set_Never_Set_In_Source
(Id
, True);
1347 Set_Is_True_Constant
(Id
, True);
1350 -- An object renaming is Ghost if the renamed entity is Ghost or the
1351 -- construct appears within a Ghost scope.
1353 if (Is_Entity_Name
(Nam
)
1354 and then Is_Ghost_Entity
(Entity
(Nam
)))
1355 or else Ghost_Mode
> None
1357 Set_Is_Ghost_Entity
(Id
);
1360 -- The entity of the renaming declaration needs to reflect whether the
1361 -- renamed object is volatile. Is_Volatile is set if the renamed object
1362 -- is volatile in the RM legality sense.
1364 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1366 -- Also copy settings of Atomic/Independent/Volatile_Full_Access
1368 if Is_Entity_Name
(Nam
) then
1369 Set_Is_Atomic
(Id
, Is_Atomic
(Entity
(Nam
)));
1370 Set_Is_Independent
(Id
, Is_Independent
(Entity
(Nam
)));
1371 Set_Is_Volatile_Full_Access
(Id
,
1372 Is_Volatile_Full_Access
(Entity
(Nam
)));
1375 -- Treat as volatile if we just set the Volatile flag
1379 -- Or if we are renaming an entity which was marked this way
1381 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1383 or else (Is_Entity_Name
(Nam
)
1384 and then Treat_As_Volatile
(Entity
(Nam
)))
1386 Set_Treat_As_Volatile
(Id
, True);
1389 -- Now make the link to the renamed object
1391 Set_Renamed_Object
(Id
, Nam
);
1393 -- Implementation-defined aspect specifications can appear in a renaming
1394 -- declaration, but not language-defined ones. The call to procedure
1395 -- Analyze_Aspect_Specifications will take care of this error check.
1397 if Has_Aspects
(N
) then
1398 Analyze_Aspect_Specifications
(N
, Id
);
1401 -- Deal with dimensions
1403 Analyze_Dimension
(N
);
1404 end Analyze_Object_Renaming
;
1406 ------------------------------
1407 -- Analyze_Package_Renaming --
1408 ------------------------------
1410 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1411 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1416 if Name
(N
) = Error
then
1420 -- The package renaming declaration may be subject to pragma Ghost with
1421 -- policy Ignore. Set the mode now to ensure that any nodes generated
1422 -- during analysis and expansion are properly flagged as ignored Ghost.
1426 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1428 Check_Text_IO_Special_Unit
(Name
(N
));
1430 if Current_Scope
/= Standard_Standard
then
1431 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1437 if Is_Entity_Name
(Name
(N
)) then
1438 Old_P
:= Entity
(Name
(N
));
1443 if Etype
(Old_P
) = Any_Type
then
1444 Error_Msg_N
("expect package name in renaming", Name
(N
));
1446 elsif Ekind
(Old_P
) /= E_Package
1447 and then not (Ekind
(Old_P
) = E_Generic_Package
1448 and then In_Open_Scopes
(Old_P
))
1450 if Ekind
(Old_P
) = E_Generic_Package
then
1452 ("generic package cannot be renamed as a package", Name
(N
));
1454 Error_Msg_Sloc
:= Sloc
(Old_P
);
1456 ("expect package name in renaming, found& declared#",
1460 -- Set basic attributes to minimize cascaded errors
1462 Set_Ekind
(New_P
, E_Package
);
1463 Set_Etype
(New_P
, Standard_Void_Type
);
1465 -- Here for OK package renaming
1468 -- Entities in the old package are accessible through the renaming
1469 -- entity. The simplest implementation is to have both packages share
1472 Set_Ekind
(New_P
, E_Package
);
1473 Set_Etype
(New_P
, Standard_Void_Type
);
1475 if Present
(Renamed_Object
(Old_P
)) then
1476 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1478 Set_Renamed_Object
(New_P
, Old_P
);
1481 Set_Has_Completion
(New_P
);
1483 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1484 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1485 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1486 Check_Library_Unit_Renaming
(N
, Old_P
);
1487 Generate_Reference
(Old_P
, Name
(N
));
1489 -- A package renaming is Ghost if the renamed entity is Ghost or
1490 -- the construct appears within a Ghost scope.
1492 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
1493 Set_Is_Ghost_Entity
(New_P
);
1496 -- If the renaming is in the visible part of a package, then we set
1497 -- Renamed_In_Spec for the renamed package, to prevent giving
1498 -- warnings about no entities referenced. Such a warning would be
1499 -- overenthusiastic, since clients can see entities in the renamed
1500 -- package via the visible package renaming.
1503 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1505 if Ekind
(Ent
) = E_Package
1506 and then not In_Private_Part
(Ent
)
1507 and then In_Extended_Main_Source_Unit
(N
)
1508 and then Ekind
(Old_P
) = E_Package
1510 Set_Renamed_In_Spec
(Old_P
);
1514 -- If this is the renaming declaration of a package instantiation
1515 -- within itself, it is the declaration that ends the list of actuals
1516 -- for the instantiation. At this point, the subtypes that rename
1517 -- the actuals are flagged as generic, to avoid spurious ambiguities
1518 -- if the actuals for two distinct formals happen to coincide. If
1519 -- the actual is a private type, the subtype has a private completion
1520 -- that is flagged in the same fashion.
1522 -- Resolution is identical to what is was in the original generic.
1523 -- On exit from the generic instance, these are turned into regular
1524 -- subtypes again, so they are compatible with types in their class.
1526 if not Is_Generic_Instance
(Old_P
) then
1529 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1532 if Nkind
(Spec
) = N_Package_Specification
1533 and then Present
(Generic_Parent
(Spec
))
1534 and then Old_P
= Current_Scope
1535 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1541 E
:= First_Entity
(Old_P
);
1542 while Present
(E
) and then E
/= New_P
loop
1544 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1546 Set_Is_Generic_Actual_Type
(E
);
1548 if Is_Private_Type
(E
)
1549 and then Present
(Full_View
(E
))
1551 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1561 -- Implementation-defined aspect specifications can appear in a renaming
1562 -- declaration, but not language-defined ones. The call to procedure
1563 -- Analyze_Aspect_Specifications will take care of this error check.
1565 if Has_Aspects
(N
) then
1566 Analyze_Aspect_Specifications
(N
, New_P
);
1568 end Analyze_Package_Renaming
;
1570 -------------------------------
1571 -- Analyze_Renamed_Character --
1572 -------------------------------
1574 procedure Analyze_Renamed_Character
1579 C
: constant Node_Id
:= Name
(N
);
1582 if Ekind
(New_S
) = E_Function
then
1583 Resolve
(C
, Etype
(New_S
));
1586 Check_Frozen_Renaming
(N
, New_S
);
1590 Error_Msg_N
("character literal can only be renamed as function", N
);
1592 end Analyze_Renamed_Character
;
1594 ---------------------------------
1595 -- Analyze_Renamed_Dereference --
1596 ---------------------------------
1598 procedure Analyze_Renamed_Dereference
1603 Nam
: constant Node_Id
:= Name
(N
);
1604 P
: constant Node_Id
:= Prefix
(Nam
);
1610 if not Is_Overloaded
(P
) then
1611 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1612 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1614 Error_Msg_N
("designated type does not match specification", P
);
1623 Get_First_Interp
(Nam
, Ind
, It
);
1625 while Present
(It
.Nam
) loop
1627 if Ekind
(It
.Nam
) = E_Subprogram_Type
1628 and then Type_Conformant
(It
.Nam
, New_S
)
1630 if Typ
/= Any_Id
then
1631 Error_Msg_N
("ambiguous renaming", P
);
1638 Get_Next_Interp
(Ind
, It
);
1641 if Typ
= Any_Type
then
1642 Error_Msg_N
("designated type does not match specification", P
);
1647 Check_Frozen_Renaming
(N
, New_S
);
1651 end Analyze_Renamed_Dereference
;
1653 ---------------------------
1654 -- Analyze_Renamed_Entry --
1655 ---------------------------
1657 procedure Analyze_Renamed_Entry
1662 Nam
: constant Node_Id
:= Name
(N
);
1663 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1664 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1668 if Entity
(Sel
) = Any_Id
then
1670 -- Selector is undefined on prefix. Error emitted already
1672 Set_Has_Completion
(New_S
);
1676 -- Otherwise find renamed entity and build body of New_S as a call to it
1678 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1680 if Old_S
= Any_Id
then
1681 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1684 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1685 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1686 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1689 -- Only mode conformance required for a renaming_as_declaration
1691 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1694 Inherit_Renamed_Profile
(New_S
, Old_S
);
1696 -- The prefix can be an arbitrary expression that yields a task or
1697 -- protected object, so it must be resolved.
1699 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1702 Set_Convention
(New_S
, Convention
(Old_S
));
1703 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1705 -- AI05-0225: If the renamed entity is a procedure or entry of a
1706 -- protected object, the target object must be a variable.
1708 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1709 and then Ekind
(New_S
) = E_Procedure
1710 and then not Is_Variable
(Prefix
(Nam
))
1714 ("target object of protected operation used as actual for "
1715 & "formal procedure must be a variable", Nam
);
1718 ("target object of protected operation renamed as procedure, "
1719 & "must be a variable", Nam
);
1724 Check_Frozen_Renaming
(N
, New_S
);
1726 end Analyze_Renamed_Entry
;
1728 -----------------------------------
1729 -- Analyze_Renamed_Family_Member --
1730 -----------------------------------
1732 procedure Analyze_Renamed_Family_Member
1737 Nam
: constant Node_Id
:= Name
(N
);
1738 P
: constant Node_Id
:= Prefix
(Nam
);
1742 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1743 or else (Nkind
(P
) = N_Selected_Component
1744 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1746 if Is_Entity_Name
(P
) then
1747 Old_S
:= Entity
(P
);
1749 Old_S
:= Entity
(Selector_Name
(P
));
1752 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1753 Error_Msg_N
("entry family does not match specification", N
);
1756 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1757 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1758 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1762 Error_Msg_N
("no entry family matches specification", N
);
1765 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1768 Check_Frozen_Renaming
(N
, New_S
);
1770 end Analyze_Renamed_Family_Member
;
1772 -----------------------------------------
1773 -- Analyze_Renamed_Primitive_Operation --
1774 -----------------------------------------
1776 procedure Analyze_Renamed_Primitive_Operation
1785 Ctyp
: Conformance_Type
) return Boolean;
1786 -- Verify that the signatures of the renamed entity and the new entity
1787 -- match. The first formal of the renamed entity is skipped because it
1788 -- is the target object in any subsequent call.
1796 Ctyp
: Conformance_Type
) return Boolean
1802 if Ekind
(Subp
) /= Ekind
(New_S
) then
1806 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1807 New_F
:= First_Formal
(New_S
);
1808 while Present
(Old_F
) and then Present
(New_F
) loop
1809 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1813 if Ctyp
>= Mode_Conformant
1814 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1819 Next_Formal
(New_F
);
1820 Next_Formal
(Old_F
);
1826 -- Start of processing for Analyze_Renamed_Primitive_Operation
1829 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1830 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1832 if not Conforms
(Old_S
, Type_Conformant
) then
1837 -- Find the operation that matches the given signature
1845 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1847 while Present
(It
.Nam
) loop
1848 if Conforms
(It
.Nam
, Type_Conformant
) then
1852 Get_Next_Interp
(Ind
, It
);
1857 if Old_S
= Any_Id
then
1858 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1862 if not Conforms
(Old_S
, Subtype_Conformant
) then
1863 Error_Msg_N
("subtype conformance error in renaming", N
);
1866 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1867 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1870 -- Only mode conformance required for a renaming_as_declaration
1872 if not Conforms
(Old_S
, Mode_Conformant
) then
1873 Error_Msg_N
("mode conformance error in renaming", N
);
1876 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1877 -- view of a subprogram is intrinsic, because the compiler has
1878 -- to generate a wrapper for any call to it. If the name in a
1879 -- subprogram renaming is a prefixed view, the entity is thus
1880 -- intrinsic, and 'Access cannot be applied to it.
1882 Set_Convention
(New_S
, Convention_Intrinsic
);
1885 -- Inherit_Renamed_Profile (New_S, Old_S);
1887 -- The prefix can be an arbitrary expression that yields an
1888 -- object, so it must be resolved.
1890 Resolve
(Prefix
(Name
(N
)));
1892 end Analyze_Renamed_Primitive_Operation
;
1894 ---------------------------------
1895 -- Analyze_Subprogram_Renaming --
1896 ---------------------------------
1898 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1899 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1900 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1901 Nam
: constant Node_Id
:= Name
(N
);
1902 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1903 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1904 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1905 Spec
: constant Node_Id
:= Specification
(N
);
1907 Old_S
: Entity_Id
:= Empty
;
1908 Rename_Spec
: Entity_Id
;
1910 procedure Build_Class_Wide_Wrapper
1911 (Ren_Id
: out Entity_Id
;
1912 Wrap_Id
: out Entity_Id
);
1913 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1914 -- type with unknown discriminants and a generic primitive operation of
1915 -- the said type with a box require special processing when the actual
1916 -- is a class-wide type:
1919 -- type Formal_Typ (<>) is private;
1920 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1921 -- package Gen is ...
1923 -- package Inst is new Gen (Actual_Typ'Class);
1925 -- In this case the general renaming mechanism used in the prologue of
1926 -- an instance no longer applies:
1928 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1930 -- The above is replaced the following wrapper/renaming combination:
1932 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1934 -- Prim_Op (Param); -- primitive
1937 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1939 -- This transformation applies only if there is no explicit visible
1940 -- class-wide operation at the point of the instantiation. Ren_Id is
1941 -- the entity of the renaming declaration. Wrap_Id is the entity of
1942 -- the generated class-wide wrapper (or Any_Id).
1944 procedure Check_Null_Exclusion
1947 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1948 -- following AI rules:
1950 -- If Ren is a renaming of a formal subprogram and one of its
1951 -- parameters has a null exclusion, then the corresponding formal
1952 -- in Sub must also have one. Otherwise the subtype of the Sub's
1953 -- formal parameter must exclude null.
1955 -- If Ren is a renaming of a formal function and its return
1956 -- profile has a null exclusion, then Sub's return profile must
1957 -- have one. Otherwise the subtype of Sub's return profile must
1960 procedure Freeze_Actual_Profile
;
1961 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1962 -- types: a callable entity freezes its profile, unless it has an
1963 -- incomplete untagged formal (RM 13.14(10.2/3)).
1965 function Has_Class_Wide_Actual
return Boolean;
1966 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1967 -- defaulted formal subprogram where the actual for the controlling
1968 -- formal type is class-wide.
1970 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1971 -- Find renamed entity when the declaration is a renaming_as_body and
1972 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1973 -- rule that a renaming_as_body is illegal if the declaration occurs
1974 -- before the subprogram it completes is frozen, and renaming indirectly
1975 -- renames the subprogram itself.(Defect Report 8652/0027).
1977 ------------------------------
1978 -- Build_Class_Wide_Wrapper --
1979 ------------------------------
1981 procedure Build_Class_Wide_Wrapper
1982 (Ren_Id
: out Entity_Id
;
1983 Wrap_Id
: out Entity_Id
)
1985 Loc
: constant Source_Ptr
:= Sloc
(N
);
1988 (Subp_Id
: Entity_Id
;
1989 Params
: List_Id
) return Node_Id
;
1990 -- Create a dispatching call to invoke routine Subp_Id with actuals
1991 -- built from the parameter specifications of list Params.
1993 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1994 -- Create a subprogram specification based on the subprogram profile
1997 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1998 -- Find a primitive subprogram of type Typ which matches the profile
1999 -- of the renaming declaration.
2001 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
2002 -- Emit a continuation error message suggesting subprogram Subp_Id as
2003 -- a possible interpretation.
2005 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
2006 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
2009 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
2010 -- Determine whether subprogram Subp_Id is a suitable candidate for
2011 -- the role of a wrapped subprogram.
2018 (Subp_Id
: Entity_Id
;
2019 Params
: List_Id
) return Node_Id
2021 Actuals
: constant List_Id
:= New_List
;
2022 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
2026 -- Build the actual parameters of the call
2028 Formal
:= First
(Params
);
2029 while Present
(Formal
) loop
2031 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2036 -- return Subp_Id (Actuals);
2038 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2040 Make_Simple_Return_Statement
(Loc
,
2042 Make_Function_Call
(Loc
,
2044 Parameter_Associations
=> Actuals
));
2047 -- Subp_Id (Actuals);
2051 Make_Procedure_Call_Statement
(Loc
,
2053 Parameter_Associations
=> Actuals
);
2061 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2062 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2063 Spec_Id
: constant Entity_Id
:=
2064 Make_Defining_Identifier
(Loc
,
2065 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2068 if Ekind
(Formal_Spec
) = E_Procedure
then
2070 Make_Procedure_Specification
(Loc
,
2071 Defining_Unit_Name
=> Spec_Id
,
2072 Parameter_Specifications
=> Params
);
2075 Make_Function_Specification
(Loc
,
2076 Defining_Unit_Name
=> Spec_Id
,
2077 Parameter_Specifications
=> Params
,
2078 Result_Definition
=>
2079 New_Copy_Tree
(Result_Definition
(Spec
)));
2083 --------------------
2084 -- Find_Primitive --
2085 --------------------
2087 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2088 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2089 -- Given a specification Spec, replace all class-wide parameter
2090 -- types with reference to type Typ.
2092 -----------------------------
2093 -- Replace_Parameter_Types --
2094 -----------------------------
2096 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2098 Formal_Id
: Entity_Id
;
2099 Formal_Typ
: Node_Id
;
2102 Formal
:= First
(Parameter_Specifications
(Spec
));
2103 while Present
(Formal
) loop
2104 Formal_Id
:= Defining_Identifier
(Formal
);
2105 Formal_Typ
:= Parameter_Type
(Formal
);
2107 -- Create a new entity for each class-wide formal to prevent
2108 -- aliasing with the original renaming. Replace the type of
2109 -- such a parameter with the candidate type.
2111 if Nkind
(Formal_Typ
) = N_Identifier
2112 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2114 Set_Defining_Identifier
(Formal
,
2115 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2117 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2122 end Replace_Parameter_Types
;
2126 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2127 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2128 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2129 Subp_Id
: Entity_Id
;
2131 -- Start of processing for Find_Primitive
2134 -- Each attempt to find a suitable primitive of a particular type
2135 -- operates on its own copy of the original renaming. As a result
2136 -- the original renaming is kept decoration and side-effect free.
2138 -- Inherit the overloaded status of the renamed subprogram name
2140 if Is_Overloaded
(Nam
) then
2141 Set_Is_Overloaded
(Alt_Nam
);
2142 Save_Interps
(Nam
, Alt_Nam
);
2145 -- The copied renaming is hidden from visibility to prevent the
2146 -- pollution of the enclosing context.
2148 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2150 -- The types of all class-wide parameters must be changed to the
2153 Replace_Parameter_Types
(Alt_Spec
);
2155 -- Try to find a suitable primitive which matches the altered
2156 -- profile of the renaming specification.
2161 Nam
=> Name
(Alt_Ren
),
2162 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2163 Is_Actual
=> Is_Actual
);
2165 -- Do not return Any_Id if the resolion of the altered profile
2166 -- failed as this complicates further checks on the caller side,
2167 -- return Empty instead.
2169 if Subp_Id
= Any_Id
then
2176 --------------------------
2177 -- Interpretation_Error --
2178 --------------------------
2180 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2182 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2184 if Is_Internal
(Subp_Id
) then
2186 ("\\possible interpretation: predefined & #",
2190 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2192 end Interpretation_Error
;
2194 ---------------------------
2195 -- Is_Intrinsic_Equality --
2196 ---------------------------
2198 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2201 Ekind
(Subp_Id
) = E_Operator
2202 and then Chars
(Subp_Id
) = Name_Op_Eq
2203 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2204 end Is_Intrinsic_Equality
;
2206 ---------------------------
2207 -- Is_Suitable_Candidate --
2208 ---------------------------
2210 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2212 if No
(Subp_Id
) then
2215 -- An intrinsic subprogram is never a good candidate. This is an
2216 -- indication of a missing primitive, either defined directly or
2217 -- inherited from a parent tagged type.
2219 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2225 end Is_Suitable_Candidate
;
2229 Actual_Typ
: Entity_Id
:= Empty
;
2230 -- The actual class-wide type for Formal_Typ
2232 CW_Prim_OK
: Boolean;
2233 CW_Prim_Op
: Entity_Id
;
2234 -- The class-wide subprogram (if available) which corresponds to the
2235 -- renamed generic formal subprogram.
2237 Formal_Typ
: Entity_Id
:= Empty
;
2238 -- The generic formal type with unknown discriminants
2240 Root_Prim_OK
: Boolean;
2241 Root_Prim_Op
: Entity_Id
;
2242 -- The root type primitive (if available) which corresponds to the
2243 -- renamed generic formal subprogram.
2245 Root_Typ
: Entity_Id
:= Empty
;
2246 -- The root type of Actual_Typ
2248 Body_Decl
: Node_Id
;
2250 Prim_Op
: Entity_Id
;
2251 Spec_Decl
: Node_Id
;
2253 -- Start of processing for Build_Class_Wide_Wrapper
2256 -- Analyze the specification of the renaming in case the generation
2257 -- of the class-wide wrapper fails.
2259 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2262 -- Do not attempt to build a wrapper if the renaming is in error
2264 if Error_Posted
(Nam
) then
2268 -- Analyze the renamed name, but do not resolve it. The resolution is
2269 -- completed once a suitable subprogram is found.
2273 -- When the renamed name denotes the intrinsic operator equals, the
2274 -- name must be treated as overloaded. This allows for a potential
2275 -- match against the root type's predefined equality function.
2277 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2278 Set_Is_Overloaded
(Nam
);
2279 Collect_Interps
(Nam
);
2282 -- Step 1: Find the generic formal type with unknown discriminants
2283 -- and its corresponding class-wide actual type from the renamed
2284 -- generic formal subprogram.
2286 Formal
:= First_Formal
(Formal_Spec
);
2287 while Present
(Formal
) loop
2288 if Has_Unknown_Discriminants
(Etype
(Formal
))
2289 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2290 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2292 Formal_Typ
:= Etype
(Formal
);
2293 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2294 Root_Typ
:= Etype
(Actual_Typ
);
2298 Next_Formal
(Formal
);
2301 -- The specification of the generic formal subprogram should always
2302 -- contain a formal type with unknown discriminants whose actual is
2303 -- a class-wide type, otherwise this indicates a failure in routine
2304 -- Has_Class_Wide_Actual.
2306 pragma Assert
(Present
(Formal_Typ
));
2308 -- Step 2: Find the proper class-wide subprogram or primitive which
2309 -- corresponds to the renamed generic formal subprogram.
2311 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2312 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2313 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2314 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2316 -- The class-wide actual type has two subprograms which correspond to
2317 -- the renamed generic formal subprogram:
2319 -- with procedure Prim_Op (Param : Formal_Typ);
2321 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2322 -- procedure Prim_Op (Param : Actual_Typ'Class);
2324 -- Even though the declaration of the two subprograms is legal, a
2325 -- call to either one is ambiguous and therefore illegal.
2327 if CW_Prim_OK
and Root_Prim_OK
then
2329 -- A user-defined primitive has precedence over a predefined one
2331 if Is_Internal
(CW_Prim_Op
)
2332 and then not Is_Internal
(Root_Prim_Op
)
2334 Prim_Op
:= Root_Prim_Op
;
2336 elsif Is_Internal
(Root_Prim_Op
)
2337 and then not Is_Internal
(CW_Prim_Op
)
2339 Prim_Op
:= CW_Prim_Op
;
2341 elsif CW_Prim_Op
= Root_Prim_Op
then
2342 Prim_Op
:= Root_Prim_Op
;
2344 -- Otherwise both candidate subprograms are user-defined and
2349 ("ambiguous actual for generic subprogram &",
2351 Interpretation_Error
(Root_Prim_Op
);
2352 Interpretation_Error
(CW_Prim_Op
);
2356 elsif CW_Prim_OK
and not Root_Prim_OK
then
2357 Prim_Op
:= CW_Prim_Op
;
2359 elsif not CW_Prim_OK
and Root_Prim_OK
then
2360 Prim_Op
:= Root_Prim_Op
;
2362 -- An intrinsic equality may act as a suitable candidate in the case
2363 -- of a null type extension where the parent's equality is hidden. A
2364 -- call to an intrinsic equality is expanded as dispatching.
2366 elsif Present
(Root_Prim_Op
)
2367 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2369 Prim_Op
:= Root_Prim_Op
;
2371 -- Otherwise there are no candidate subprograms. Let the caller
2372 -- diagnose the error.
2378 -- At this point resolution has taken place and the name is no longer
2379 -- overloaded. Mark the primitive as referenced.
2381 Set_Is_Overloaded
(Name
(N
), False);
2382 Set_Referenced
(Prim_Op
);
2384 -- Step 3: Create the declaration and the body of the wrapper, insert
2385 -- all the pieces into the tree.
2388 Make_Subprogram_Declaration
(Loc
,
2389 Specification
=> Build_Spec
(Ren_Id
));
2390 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2392 -- If the operator carries an Eliminated pragma, indicate that the
2393 -- wrapper is also to be eliminated, to prevent spurious error when
2394 -- using gnatelim on programs that include box-initialization of
2395 -- equality operators.
2397 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2398 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2401 Make_Subprogram_Body
(Loc
,
2402 Specification
=> Build_Spec
(Ren_Id
),
2403 Declarations
=> New_List
,
2404 Handled_Statement_Sequence
=>
2405 Make_Handled_Sequence_Of_Statements
(Loc
,
2406 Statements
=> New_List
(
2408 (Subp_Id
=> Prim_Op
,
2410 Parameter_Specifications
2411 (Specification
(Spec_Decl
))))));
2413 -- The generated body does not freeze and must be analyzed when the
2414 -- class-wide wrapper is frozen. The body is only needed if expansion
2417 if Expander_Active
then
2418 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2421 -- Step 4: The subprogram renaming aliases the wrapper
2423 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2424 end Build_Class_Wide_Wrapper
;
2426 --------------------------
2427 -- Check_Null_Exclusion --
2428 --------------------------
2430 procedure Check_Null_Exclusion
2434 Ren_Formal
: Entity_Id
;
2435 Sub_Formal
: Entity_Id
;
2440 Ren_Formal
:= First_Formal
(Ren
);
2441 Sub_Formal
:= First_Formal
(Sub
);
2442 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2443 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2445 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2446 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2449 ("`NOT NULL` required for parameter &",
2450 Parent
(Sub_Formal
), Sub_Formal
);
2453 Next_Formal
(Ren_Formal
);
2454 Next_Formal
(Sub_Formal
);
2457 -- Return profile check
2459 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2460 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2461 and then Has_Null_Exclusion
(Parent
(Ren
))
2462 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2463 or else Can_Never_Be_Null
(Etype
(Sub
)))
2466 ("return must specify `NOT NULL`",
2467 Result_Definition
(Parent
(Sub
)));
2469 end Check_Null_Exclusion
;
2471 ---------------------------
2472 -- Freeze_Actual_Profile --
2473 ---------------------------
2475 procedure Freeze_Actual_Profile
is
2477 Has_Untagged_Inc
: Boolean;
2478 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2481 if Ada_Version
>= Ada_2012
then
2482 F
:= First_Formal
(Formal_Spec
);
2483 Has_Untagged_Inc
:= False;
2484 while Present
(F
) loop
2485 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2486 and then not Is_Tagged_Type
(Etype
(F
))
2488 Has_Untagged_Inc
:= True;
2492 F
:= Next_Formal
(F
);
2495 if Ekind
(Formal_Spec
) = E_Function
2496 and then Ekind
(Etype
(Formal_Spec
)) = E_Incomplete_Type
2497 and then not Is_Tagged_Type
(Etype
(F
))
2499 Has_Untagged_Inc
:= True;
2502 if not Has_Untagged_Inc
then
2503 F
:= First_Formal
(Old_S
);
2504 while Present
(F
) loop
2505 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2507 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2508 and then No
(Underlying_Type
(Etype
(F
)))
2510 -- Exclude generic types, or types derived from them.
2511 -- They will be frozen in the enclosing instance.
2513 if Is_Generic_Type
(Etype
(F
))
2514 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2519 ("type& must be frozen before this point",
2520 Instantiation_Node
, Etype
(F
));
2524 F
:= Next_Formal
(F
);
2528 end Freeze_Actual_Profile
;
2530 ---------------------------
2531 -- Has_Class_Wide_Actual --
2532 ---------------------------
2534 function Has_Class_Wide_Actual
return Boolean is
2536 Formal_Typ
: Entity_Id
;
2540 Formal
:= First_Formal
(Formal_Spec
);
2541 while Present
(Formal
) loop
2542 Formal_Typ
:= Etype
(Formal
);
2544 if Has_Unknown_Discriminants
(Formal_Typ
)
2545 and then not Is_Class_Wide_Type
(Formal_Typ
)
2546 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2551 Next_Formal
(Formal
);
2556 end Has_Class_Wide_Actual
;
2558 -------------------------
2559 -- Original_Subprogram --
2560 -------------------------
2562 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2563 Orig_Decl
: Node_Id
;
2564 Orig_Subp
: Entity_Id
;
2567 -- First case: renamed entity is itself a renaming
2569 if Present
(Alias
(Subp
)) then
2570 return Alias
(Subp
);
2572 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2573 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2575 -- Check if renamed entity is a renaming_as_body
2578 Unit_Declaration_Node
2579 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2581 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2582 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2584 if Orig_Subp
= Rename_Spec
then
2586 -- Circularity detected
2591 return (Original_Subprogram
(Orig_Subp
));
2599 end Original_Subprogram
;
2603 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2604 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2605 -- defaulted formal subprogram when the actual for a related formal
2606 -- type is class-wide.
2608 Inst_Node
: Node_Id
:= Empty
;
2611 -- Start of processing for Analyze_Subprogram_Renaming
2614 -- The subprogram renaming declaration may be subject to pragma Ghost
2615 -- with policy Ignore. Set the mode now to ensure that any nodes
2616 -- generated during analysis and expansion are properly flagged as
2621 -- We must test for the attribute renaming case before the Analyze
2622 -- call because otherwise Sem_Attr will complain that the attribute
2623 -- is missing an argument when it is analyzed.
2625 if Nkind
(Nam
) = N_Attribute_Reference
then
2627 -- In the case of an abstract formal subprogram association, rewrite
2628 -- an actual given by a stream attribute as the name of the
2629 -- corresponding stream primitive of the type.
2631 -- In a generic context the stream operations are not generated, and
2632 -- this must be treated as a normal attribute reference, to be
2633 -- expanded in subsequent instantiations.
2636 and then Is_Abstract_Subprogram
(Formal_Spec
)
2637 and then Expander_Active
2640 Stream_Prim
: Entity_Id
;
2641 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2644 -- The class-wide forms of the stream attributes are not
2645 -- primitive dispatching operations (even though they
2646 -- internally dispatch to a stream attribute).
2648 if Is_Class_Wide_Type
(Prefix_Type
) then
2650 ("attribute must be a primitive dispatching operation",
2655 -- Retrieve the primitive subprogram associated with the
2656 -- attribute. This can only be a stream attribute, since those
2657 -- are the only ones that are dispatching (and the actual for
2658 -- an abstract formal subprogram must be dispatching
2661 case Attribute_Name
(Nam
) is
2664 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2667 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2670 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2673 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2676 ("attribute must be a primitive"
2677 & " dispatching operation", Nam
);
2681 -- If no operation was found, and the type is limited,
2682 -- the user should have defined one.
2684 if No
(Stream_Prim
) then
2685 if Is_Limited_Type
(Prefix_Type
) then
2687 ("stream operation not defined for type&",
2691 -- Otherwise, compiler should have generated default
2694 raise Program_Error
;
2698 -- Rewrite the attribute into the name of its corresponding
2699 -- primitive dispatching subprogram. We can then proceed with
2700 -- the usual processing for subprogram renamings.
2703 Prim_Name
: constant Node_Id
:=
2704 Make_Identifier
(Sloc
(Nam
),
2705 Chars
=> Chars
(Stream_Prim
));
2707 Set_Entity
(Prim_Name
, Stream_Prim
);
2708 Rewrite
(Nam
, Prim_Name
);
2713 -- Normal processing for a renaming of an attribute
2716 Attribute_Renaming
(N
);
2721 -- Check whether this declaration corresponds to the instantiation
2722 -- of a formal subprogram.
2724 -- If this is an instantiation, the corresponding actual is frozen and
2725 -- error messages can be made more precise. If this is a default
2726 -- subprogram, the entity is already established in the generic, and is
2727 -- not retrieved by visibility. If it is a default with a box, the
2728 -- candidate interpretations, if any, have been collected when building
2729 -- the renaming declaration. If overloaded, the proper interpretation is
2730 -- determined in Find_Renamed_Entity. If the entity is an operator,
2731 -- Find_Renamed_Entity applies additional visibility checks.
2734 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2736 -- Check whether the renaming is for a defaulted actual subprogram
2737 -- with a class-wide actual.
2739 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2740 -- is an external axiomatization on the package.
2743 and then Box_Present
(Inst_Node
)
2747 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2749 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2751 elsif Is_Entity_Name
(Nam
)
2752 and then Present
(Entity
(Nam
))
2753 and then not Comes_From_Source
(Nam
)
2754 and then not Is_Overloaded
(Nam
)
2756 Old_S
:= Entity
(Nam
);
2757 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2761 if Ekind
(Entity
(Nam
)) = E_Operator
then
2765 if Box_Present
(Inst_Node
) then
2766 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2768 -- If there is an immediately visible homonym of the operator
2769 -- and the declaration has a default, this is worth a warning
2770 -- because the user probably did not intend to get the pre-
2771 -- defined operator, visible in the generic declaration. To
2772 -- find if there is an intended candidate, analyze the renaming
2773 -- again in the current context.
2775 elsif Scope
(Old_S
) = Standard_Standard
2776 and then Present
(Default_Name
(Inst_Node
))
2779 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2783 Set_Entity
(Name
(Decl
), Empty
);
2784 Analyze
(Name
(Decl
));
2786 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2789 and then In_Open_Scopes
(Scope
(Hidden
))
2790 and then Is_Immediately_Visible
(Hidden
)
2791 and then Comes_From_Source
(Hidden
)
2792 and then Hidden
/= Old_S
2794 Error_Msg_Sloc
:= Sloc
(Hidden
);
2795 Error_Msg_N
("default subprogram is resolved " &
2796 "in the generic declaration " &
2797 "(RM 12.6(17))??", N
);
2798 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2806 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2810 -- Renamed entity must be analyzed first, to avoid being hidden by
2811 -- new name (which might be the same in a generic instance).
2815 -- The renaming defines a new overloaded entity, which is analyzed
2816 -- like a subprogram declaration.
2818 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2821 if Current_Scope
/= Standard_Standard
then
2822 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2825 -- Set SPARK mode from current context
2827 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2828 Set_SPARK_Pragma_Inherited
(New_S
, True);
2830 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2832 -- Case of Renaming_As_Body
2834 if Present
(Rename_Spec
) then
2836 -- Renaming declaration is the completion of the declaration of
2837 -- Rename_Spec. We build an actual body for it at the freezing point.
2839 Set_Corresponding_Spec
(N
, Rename_Spec
);
2841 -- Deal with special case of stream functions of abstract types
2844 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2845 N_Abstract_Subprogram_Declaration
2847 -- Input stream functions are abstract if the object type is
2848 -- abstract. Similarly, all default stream functions for an
2849 -- interface type are abstract. However, these subprograms may
2850 -- receive explicit declarations in representation clauses, making
2851 -- the attribute subprograms usable as defaults in subsequent
2853 -- In this case we rewrite the declaration to make the subprogram
2854 -- non-abstract. We remove the previous declaration, and insert
2855 -- the new one at the point of the renaming, to prevent premature
2856 -- access to unfrozen types. The new declaration reuses the
2857 -- specification of the previous one, and must not be analyzed.
2860 (Is_Primitive
(Entity
(Nam
))
2862 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2864 Old_Decl
: constant Node_Id
:=
2865 Unit_Declaration_Node
(Rename_Spec
);
2866 New_Decl
: constant Node_Id
:=
2867 Make_Subprogram_Declaration
(Sloc
(N
),
2869 Relocate_Node
(Specification
(Old_Decl
)));
2872 Insert_After
(N
, New_Decl
);
2873 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2874 Set_Analyzed
(New_Decl
);
2878 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2880 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2881 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2884 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2885 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2886 Set_Public_Status
(New_S
);
2888 -- The specification does not introduce new formals, but only
2889 -- repeats the formals of the original subprogram declaration.
2890 -- For cross-reference purposes, and for refactoring tools, we
2891 -- treat the formals of the renaming declaration as body formals.
2893 Reference_Body_Formals
(Rename_Spec
, New_S
);
2895 -- Indicate that the entity in the declaration functions like the
2896 -- corresponding body, and is not a new entity. The body will be
2897 -- constructed later at the freeze point, so indicate that the
2898 -- completion has not been seen yet.
2900 Set_Ekind
(New_S
, E_Subprogram_Body
);
2901 New_S
:= Rename_Spec
;
2902 Set_Has_Completion
(Rename_Spec
, False);
2904 -- Ada 2005: check overriding indicator
2906 if Present
(Overridden_Operation
(Rename_Spec
)) then
2907 if Must_Not_Override
(Specification
(N
)) then
2909 ("subprogram& overrides inherited operation",
2912 Style_Check
and then not Must_Override
(Specification
(N
))
2914 Style
.Missing_Overriding
(N
, Rename_Spec
);
2917 elsif Must_Override
(Specification
(N
)) then
2918 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2921 -- Normal subprogram renaming (not renaming as body)
2924 Generate_Definition
(New_S
);
2925 New_Overloaded_Entity
(New_S
);
2927 if Is_Entity_Name
(Nam
)
2928 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2932 Check_Delayed_Subprogram
(New_S
);
2936 -- There is no need for elaboration checks on the new entity, which may
2937 -- be called before the next freezing point where the body will appear.
2938 -- Elaboration checks refer to the real entity, not the one created by
2939 -- the renaming declaration.
2941 Set_Kill_Elaboration_Checks
(New_S
, True);
2943 -- If we had a previous error, indicate a completely is present to stop
2944 -- junk cascaded messages, but don't take any further action.
2946 if Etype
(Nam
) = Any_Type
then
2947 Set_Has_Completion
(New_S
);
2950 -- Case where name has the form of a selected component
2952 elsif Nkind
(Nam
) = N_Selected_Component
then
2954 -- A name which has the form A.B can designate an entry of task A, a
2955 -- protected operation of protected object A, or finally a primitive
2956 -- operation of object A. In the later case, A is an object of some
2957 -- tagged type, or an access type that denotes one such. To further
2958 -- distinguish these cases, note that the scope of a task entry or
2959 -- protected operation is type of the prefix.
2961 -- The prefix could be an overloaded function call that returns both
2962 -- kinds of operations. This overloading pathology is left to the
2963 -- dedicated reader ???
2966 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2974 and then Is_Tagged_Type
(Designated_Type
(T
))))
2975 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2977 Analyze_Renamed_Primitive_Operation
2978 (N
, New_S
, Present
(Rename_Spec
));
2982 -- Renamed entity is an entry or protected operation. For those
2983 -- cases an explicit body is built (at the point of freezing of
2984 -- this entity) that contains a call to the renamed entity.
2986 -- This is not allowed for renaming as body if the renamed
2987 -- spec is already frozen (see RM 8.5.4(5) for details).
2989 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
2991 ("renaming-as-body cannot rename entry as subprogram", N
);
2993 ("\since & is already frozen (RM 8.5.4(5))",
2996 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
3003 -- Case where name is an explicit dereference X.all
3005 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
3007 -- Renamed entity is designated by access_to_subprogram expression.
3008 -- Must build body to encapsulate call, as in the entry case.
3010 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
3013 -- Indexed component
3015 elsif Nkind
(Nam
) = N_Indexed_Component
then
3016 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
3019 -- Character literal
3021 elsif Nkind
(Nam
) = N_Character_Literal
then
3022 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
3025 -- Only remaining case is where we have a non-entity name, or a renaming
3026 -- of some other non-overloadable entity.
3028 elsif not Is_Entity_Name
(Nam
)
3029 or else not Is_Overloadable
(Entity
(Nam
))
3031 -- Do not mention the renaming if it comes from an instance
3033 if not Is_Actual
then
3034 Error_Msg_N
("expect valid subprogram name in renaming", N
);
3036 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3042 -- Find the renamed entity that matches the given specification. Disable
3043 -- Ada_83 because there is no requirement of full conformance between
3044 -- renamed entity and new entity, even though the same circuit is used.
3046 -- This is a bit of an odd case, which introduces a really irregular use
3047 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3050 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3051 Ada_Version_Pragma
:= Empty
;
3052 Ada_Version_Explicit
:= Ada_Version
;
3055 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3057 -- The visible operation may be an inherited abstract operation that
3058 -- was overridden in the private part, in which case a call will
3059 -- dispatch to the overriding operation. Use the overriding one in
3060 -- the renaming declaration, to prevent spurious errors below.
3062 if Is_Overloadable
(Old_S
)
3063 and then Is_Abstract_Subprogram
(Old_S
)
3064 and then No
(DTC_Entity
(Old_S
))
3065 and then Present
(Alias
(Old_S
))
3066 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3067 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3069 Old_S
:= Alias
(Old_S
);
3072 -- When the renamed subprogram is overloaded and used as an actual
3073 -- of a generic, its entity is set to the first available homonym.
3074 -- We must first disambiguate the name, then set the proper entity.
3076 if Is_Actual
and then Is_Overloaded
(Nam
) then
3077 Set_Entity
(Nam
, Old_S
);
3081 -- Most common case: subprogram renames subprogram. No body is generated
3082 -- in this case, so we must indicate the declaration is complete as is.
3083 -- and inherit various attributes of the renamed subprogram.
3085 if No
(Rename_Spec
) then
3086 Set_Has_Completion
(New_S
);
3087 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3088 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3089 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3091 -- A subprogram renaming is Ghost if the renamed entity is Ghost or
3092 -- the construct appears within a Ghost scope.
3094 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
3095 Set_Is_Ghost_Entity
(New_S
);
3098 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3099 -- between a subprogram and its correct renaming.
3101 -- Note: the Any_Id check is a guard that prevents compiler crashes
3102 -- when performing a null exclusion check between a renaming and a
3103 -- renamed subprogram that has been found to be illegal.
3105 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3106 Check_Null_Exclusion
3108 Sub
=> Entity
(Nam
));
3111 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3112 -- overriding. The flag Requires_Overriding is set very selectively
3113 -- and misses some other illegal cases. The additional conditions
3114 -- checked below are sufficient but not necessary ???
3116 -- The rule does not apply to the renaming generated for an actual
3117 -- subprogram in an instance.
3122 -- Guard against previous errors, and omit renamings of predefined
3125 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3128 elsif Requires_Overriding
(Old_S
)
3130 (Is_Abstract_Subprogram
(Old_S
)
3131 and then Present
(Find_Dispatching_Type
(Old_S
))
3133 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3136 ("renamed entity cannot be "
3137 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3141 if Old_S
/= Any_Id
then
3142 if Is_Actual
and then From_Default
(N
) then
3144 -- This is an implicit reference to the default actual
3146 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3149 Generate_Reference
(Old_S
, Nam
);
3152 Check_Internal_Protected_Use
(N
, Old_S
);
3154 -- For a renaming-as-body, require subtype conformance, but if the
3155 -- declaration being completed has not been frozen, then inherit the
3156 -- convention of the renamed subprogram prior to checking conformance
3157 -- (unless the renaming has an explicit convention established; the
3158 -- rule stated in the RM doesn't seem to address this ???).
3160 if Present
(Rename_Spec
) then
3161 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3162 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3164 if not Is_Frozen
(Rename_Spec
) then
3165 if not Has_Convention_Pragma
(Rename_Spec
) then
3166 Set_Convention
(New_S
, Convention
(Old_S
));
3169 if Ekind
(Old_S
) /= E_Operator
then
3170 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3173 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3174 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3177 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3180 Check_Frozen_Renaming
(N
, Rename_Spec
);
3182 -- Check explicitly that renamed entity is not intrinsic, because
3183 -- in a generic the renamed body is not built. In this case,
3184 -- the renaming_as_body is a completion.
3186 if Inside_A_Generic
then
3187 if Is_Frozen
(Rename_Spec
)
3188 and then Is_Intrinsic_Subprogram
(Old_S
)
3191 ("subprogram in renaming_as_body cannot be intrinsic",
3195 Set_Has_Completion
(Rename_Spec
);
3198 elsif Ekind
(Old_S
) /= E_Operator
then
3200 -- If this a defaulted subprogram for a class-wide actual there is
3201 -- no check for mode conformance, given that the signatures don't
3202 -- match (the source mentions T but the actual mentions T'Class).
3206 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3207 Check_Mode_Conformant
(New_S
, Old_S
);
3210 if Is_Actual
and then Error_Posted
(New_S
) then
3211 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3215 if No
(Rename_Spec
) then
3217 -- The parameter profile of the new entity is that of the renamed
3218 -- entity: the subtypes given in the specification are irrelevant.
3220 Inherit_Renamed_Profile
(New_S
, Old_S
);
3222 -- A call to the subprogram is transformed into a call to the
3223 -- renamed entity. This is transitive if the renamed entity is
3224 -- itself a renaming.
3226 if Present
(Alias
(Old_S
)) then
3227 Set_Alias
(New_S
, Alias
(Old_S
));
3229 Set_Alias
(New_S
, Old_S
);
3232 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3233 -- renaming as body, since the entity in this case is not an
3234 -- intrinsic (it calls an intrinsic, but we have a real body for
3235 -- this call, and it is in this body that the required intrinsic
3236 -- processing will take place).
3238 -- Also, if this is a renaming of inequality, the renamed operator
3239 -- is intrinsic, but what matters is the corresponding equality
3240 -- operator, which may be user-defined.
3242 Set_Is_Intrinsic_Subprogram
3244 Is_Intrinsic_Subprogram
(Old_S
)
3246 (Chars
(Old_S
) /= Name_Op_Ne
3247 or else Ekind
(Old_S
) = E_Operator
3248 or else Is_Intrinsic_Subprogram
3249 (Corresponding_Equality
(Old_S
))));
3251 if Ekind
(Alias
(New_S
)) = E_Operator
then
3252 Set_Has_Delayed_Freeze
(New_S
, False);
3255 -- If the renaming corresponds to an association for an abstract
3256 -- formal subprogram, then various attributes must be set to
3257 -- indicate that the renaming is an abstract dispatching operation
3258 -- with a controlling type.
3260 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3262 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3263 -- see it as corresponding to a generic association for a
3264 -- formal abstract subprogram
3266 Set_Is_Abstract_Subprogram
(New_S
);
3269 New_S_Ctrl_Type
: constant Entity_Id
:=
3270 Find_Dispatching_Type
(New_S
);
3271 Old_S_Ctrl_Type
: constant Entity_Id
:=
3272 Find_Dispatching_Type
(Old_S
);
3275 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
3277 ("actual must be dispatching subprogram for type&",
3278 Nam
, New_S_Ctrl_Type
);
3281 Set_Is_Dispatching_Operation
(New_S
);
3282 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3284 -- If the actual in the formal subprogram is itself a
3285 -- formal abstract subprogram association, there's no
3286 -- dispatch table component or position to inherit.
3288 if Present
(DTC_Entity
(Old_S
)) then
3289 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3290 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3300 -- The following is illegal, because F hides whatever other F may
3302 -- function F (...) renames F;
3305 or else (Nkind
(Nam
) /= N_Expanded_Name
3306 and then Chars
(Old_S
) = Chars
(New_S
))
3308 Error_Msg_N
("subprogram cannot rename itself", N
);
3310 -- This is illegal even if we use a selector:
3311 -- function F (...) renames Pkg.F;
3312 -- because F is still hidden.
3314 elsif Nkind
(Nam
) = N_Expanded_Name
3315 and then Entity
(Prefix
(Nam
)) = Current_Scope
3316 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3318 -- This is an error, but we overlook the error and accept the
3319 -- renaming if the special Overriding_Renamings mode is in effect.
3321 if not Overriding_Renamings
then
3323 ("implicit operation& is not visible (RM 8.3 (15))",
3328 Set_Convention
(New_S
, Convention
(Old_S
));
3330 if Is_Abstract_Subprogram
(Old_S
) then
3331 if Present
(Rename_Spec
) then
3333 ("a renaming-as-body cannot rename an abstract subprogram",
3335 Set_Has_Completion
(Rename_Spec
);
3337 Set_Is_Abstract_Subprogram
(New_S
);
3341 Check_Library_Unit_Renaming
(N
, Old_S
);
3343 -- Pathological case: procedure renames entry in the scope of its
3344 -- task. Entry is given by simple name, but body must be built for
3345 -- procedure. Of course if called it will deadlock.
3347 if Ekind
(Old_S
) = E_Entry
then
3348 Set_Has_Completion
(New_S
, False);
3349 Set_Alias
(New_S
, Empty
);
3353 Freeze_Before
(N
, Old_S
);
3354 Freeze_Actual_Profile
;
3355 Set_Has_Delayed_Freeze
(New_S
, False);
3356 Freeze_Before
(N
, New_S
);
3358 -- An abstract subprogram is only allowed as an actual in the case
3359 -- where the formal subprogram is also abstract.
3361 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3362 and then Is_Abstract_Subprogram
(Old_S
)
3363 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3366 ("abstract subprogram not allowed as generic actual", Nam
);
3371 -- A common error is to assume that implicit operators for types are
3372 -- defined in Standard, or in the scope of a subtype. In those cases
3373 -- where the renamed entity is given with an expanded name, it is
3374 -- worth mentioning that operators for the type are not declared in
3375 -- the scope given by the prefix.
3377 if Nkind
(Nam
) = N_Expanded_Name
3378 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3379 and then Scope
(Entity
(Nam
)) = Standard_Standard
3382 T
: constant Entity_Id
:=
3383 Base_Type
(Etype
(First_Formal
(New_S
)));
3385 Error_Msg_Node_2
:= Prefix
(Nam
);
3387 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3392 ("no visible subprogram matches the specification for&",
3396 if Present
(Candidate_Renaming
) then
3403 F1
:= First_Formal
(Candidate_Renaming
);
3404 F2
:= First_Formal
(New_S
);
3405 T1
:= First_Subtype
(Etype
(F1
));
3406 while Present
(F1
) and then Present
(F2
) loop
3411 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3412 if Present
(Next_Formal
(F1
)) then
3414 ("\missing specification for &" &
3415 " and other formals with defaults", Spec
, F1
);
3418 ("\missing specification for &", Spec
, F1
);
3422 if Nkind
(Nam
) = N_Operator_Symbol
3423 and then From_Default
(N
)
3425 Error_Msg_Node_2
:= T1
;
3427 ("default & on & is not directly visible",
3434 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3435 -- controlling access parameters are known non-null for the renamed
3436 -- subprogram. Test also applies to a subprogram instantiation that
3437 -- is dispatching. Test is skipped if some previous error was detected
3438 -- that set Old_S to Any_Id.
3440 if Ada_Version
>= Ada_2005
3441 and then Old_S
/= Any_Id
3442 and then not Is_Dispatching_Operation
(Old_S
)
3443 and then Is_Dispatching_Operation
(New_S
)
3450 Old_F
:= First_Formal
(Old_S
);
3451 New_F
:= First_Formal
(New_S
);
3452 while Present
(Old_F
) loop
3453 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3454 and then Is_Controlling_Formal
(New_F
)
3455 and then not Can_Never_Be_Null
(Old_F
)
3457 Error_Msg_N
("access parameter is controlling,", New_F
);
3459 ("\corresponding parameter of& "
3460 & "must be explicitly null excluding", New_F
, Old_S
);
3463 Next_Formal
(Old_F
);
3464 Next_Formal
(New_F
);
3469 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3470 -- is to warn if an operator is being renamed as a different operator.
3471 -- If the operator is predefined, examine the kind of the entity, not
3472 -- the abbreviated declaration in Standard.
3474 if Comes_From_Source
(N
)
3475 and then Present
(Old_S
)
3476 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3477 or else Ekind
(Old_S
) = E_Operator
)
3478 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3479 and then Chars
(Old_S
) /= Chars
(New_S
)
3482 ("& is being renamed as a different operator??", N
, Old_S
);
3485 -- Check for renaming of obsolescent subprogram
3487 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3489 -- Another warning or some utility: if the new subprogram as the same
3490 -- name as the old one, the old one is not hidden by an outer homograph,
3491 -- the new one is not a public symbol, and the old one is otherwise
3492 -- directly visible, the renaming is superfluous.
3494 if Chars
(Old_S
) = Chars
(New_S
)
3495 and then Comes_From_Source
(N
)
3496 and then Scope
(Old_S
) /= Standard_Standard
3497 and then Warn_On_Redundant_Constructs
3498 and then (Is_Immediately_Visible
(Old_S
)
3499 or else Is_Potentially_Use_Visible
(Old_S
))
3500 and then Is_Overloadable
(Current_Scope
)
3501 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3504 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3507 -- Implementation-defined aspect specifications can appear in a renaming
3508 -- declaration, but not language-defined ones. The call to procedure
3509 -- Analyze_Aspect_Specifications will take care of this error check.
3511 if Has_Aspects
(N
) then
3512 Analyze_Aspect_Specifications
(N
, New_S
);
3515 Ada_Version
:= Save_AV
;
3516 Ada_Version_Pragma
:= Save_AVP
;
3517 Ada_Version_Explicit
:= Save_AV_Exp
;
3519 -- In GNATprove mode, the renamings of actual subprograms are replaced
3520 -- with wrapper functions that make it easier to propagate axioms to the
3521 -- points of call within an instance. Wrappers are generated if formal
3522 -- subprogram is subject to axiomatization.
3524 -- The types in the wrapper profiles are obtained from (instances of)
3525 -- the types of the formal subprogram.
3528 and then GNATprove_Mode
3529 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3530 and then not Inside_A_Generic
3532 if Ekind
(Old_S
) = E_Function
then
3533 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3536 elsif Ekind
(Old_S
) = E_Operator
then
3537 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3541 end Analyze_Subprogram_Renaming
;
3543 -------------------------
3544 -- Analyze_Use_Package --
3545 -------------------------
3547 -- Resolve the package names in the use clause, and make all the visible
3548 -- entities defined in the package potentially use-visible. If the package
3549 -- is already in use from a previous use clause, its visible entities are
3550 -- already use-visible. In that case, mark the occurrence as a redundant
3551 -- use. If the package is an open scope, i.e. if the use clause occurs
3552 -- within the package itself, ignore it.
3554 procedure Analyze_Use_Package
(N
: Node_Id
) is
3555 Pack_Name
: Node_Id
;
3558 -- Start of processing for Analyze_Use_Package
3561 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3563 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3565 -- Use clause not allowed in a spec of a predefined package declaration
3566 -- except that packages whose file name starts a-n are OK (these are
3567 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3569 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3570 and then Name_Buffer
(1 .. 3) /= "a-n"
3572 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3574 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3577 -- Chain clause to list of use clauses in current scope
3579 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3580 Chain_Use_Clause
(N
);
3583 -- Loop through package names to identify referenced packages
3585 Pack_Name
:= First
(Names
(N
));
3586 while Present
(Pack_Name
) loop
3587 Analyze
(Pack_Name
);
3589 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3590 and then Nkind
(Pack_Name
) = N_Expanded_Name
3596 Pref
:= Prefix
(Pack_Name
);
3597 while Nkind
(Pref
) = N_Expanded_Name
loop
3598 Pref
:= Prefix
(Pref
);
3601 if Entity
(Pref
) = Standard_Standard
then
3603 ("predefined package Standard cannot appear"
3604 & " in a context clause", Pref
);
3612 -- Loop through package names to mark all entities as potentially
3615 Pack_Name
:= First
(Names
(N
));
3616 while Present
(Pack_Name
) loop
3617 if Is_Entity_Name
(Pack_Name
) then
3618 Pack
:= Entity
(Pack_Name
);
3620 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3621 if Ekind
(Pack
) = E_Generic_Package
then
3622 Error_Msg_N
-- CODEFIX
3623 ("a generic package is not allowed in a use clause",
3626 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3628 Error_Msg_N
-- CODEFIX
3629 ("a generic subprogram is not allowed in a use clause",
3632 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3633 Error_Msg_N
-- CODEFIX
3634 ("a subprogram is not allowed in a use clause",
3638 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3642 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3643 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3646 if Applicable_Use
(Pack_Name
) then
3647 Use_One_Package
(Pack
, N
);
3651 -- Report error because name denotes something other than a package
3654 Error_Msg_N
("& is not a package", Pack_Name
);
3659 end Analyze_Use_Package
;
3661 ----------------------
3662 -- Analyze_Use_Type --
3663 ----------------------
3665 procedure Analyze_Use_Type
(N
: Node_Id
) is
3670 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3672 -- Chain clause to list of use clauses in current scope
3674 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3675 Chain_Use_Clause
(N
);
3678 -- If the Used_Operations list is already initialized, the clause has
3679 -- been analyzed previously, and it is begin reinstalled, for example
3680 -- when the clause appears in a package spec and we are compiling the
3681 -- corresponding package body. In that case, make the entities on the
3682 -- existing list use_visible, and mark the corresponding types In_Use.
3684 if Present
(Used_Operations
(N
)) then
3690 Mark
:= First
(Subtype_Marks
(N
));
3691 while Present
(Mark
) loop
3692 Use_One_Type
(Mark
, Installed
=> True);
3696 Elmt
:= First_Elmt
(Used_Operations
(N
));
3697 while Present
(Elmt
) loop
3698 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3706 -- Otherwise, create new list and attach to it the operations that
3707 -- are made use-visible by the clause.
3709 Set_Used_Operations
(N
, New_Elmt_List
);
3710 Id
:= First
(Subtype_Marks
(N
));
3711 while Present
(Id
) loop
3715 if E
/= Any_Type
then
3718 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3719 if Nkind
(Id
) = N_Identifier
then
3720 Error_Msg_N
("type is not directly visible", Id
);
3722 elsif Is_Child_Unit
(Scope
(E
))
3723 and then Scope
(E
) /= System_Aux_Id
3725 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3730 -- If the use_type_clause appears in a compilation unit context,
3731 -- check whether it comes from a unit that may appear in a
3732 -- limited_with_clause, for a better error message.
3734 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3735 and then Nkind
(Id
) /= N_Identifier
3741 function Mentioned
(Nam
: Node_Id
) return Boolean;
3742 -- Check whether the prefix of expanded name for the type
3743 -- appears in the prefix of some limited_with_clause.
3749 function Mentioned
(Nam
: Node_Id
) return Boolean is
3751 return Nkind
(Name
(Item
)) = N_Selected_Component
3752 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3756 Pref
:= Prefix
(Id
);
3757 Item
:= First
(Context_Items
(Parent
(N
)));
3758 while Present
(Item
) and then Item
/= N
loop
3759 if Nkind
(Item
) = N_With_Clause
3760 and then Limited_Present
(Item
)
3761 and then Mentioned
(Pref
)
3764 (Get_Msg_Id
, "premature usage of incomplete type");
3775 end Analyze_Use_Type
;
3777 --------------------
3778 -- Applicable_Use --
3779 --------------------
3781 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3782 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3785 if In_Open_Scopes
(Pack
) then
3786 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3787 Error_Msg_NE
-- CODEFIX
3788 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3793 elsif In_Use
(Pack
) then
3794 Note_Redundant_Use
(Pack_Name
);
3797 elsif Present
(Renamed_Object
(Pack
))
3798 and then In_Use
(Renamed_Object
(Pack
))
3800 Note_Redundant_Use
(Pack_Name
);
3808 ------------------------
3809 -- Attribute_Renaming --
3810 ------------------------
3812 procedure Attribute_Renaming
(N
: Node_Id
) is
3813 Loc
: constant Source_Ptr
:= Sloc
(N
);
3814 Nam
: constant Node_Id
:= Name
(N
);
3815 Spec
: constant Node_Id
:= Specification
(N
);
3816 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3817 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3819 Form_Num
: Nat
:= 0;
3820 Expr_List
: List_Id
:= No_List
;
3822 Attr_Node
: Node_Id
;
3823 Body_Node
: Node_Id
;
3824 Param_Spec
: Node_Id
;
3827 Generate_Definition
(New_S
);
3829 -- This procedure is called in the context of subprogram renaming, and
3830 -- thus the attribute must be one that is a subprogram. All of those
3831 -- have at least one formal parameter, with the exceptions of the GNAT
3832 -- attribute 'Img, which GNAT treats as renameable.
3834 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3835 if Aname
/= Name_Img
then
3837 ("subprogram renaming an attribute must have formals", N
);
3842 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3843 while Present
(Param_Spec
) loop
3844 Form_Num
:= Form_Num
+ 1;
3846 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3847 Find_Type
(Parameter_Type
(Param_Spec
));
3849 -- The profile of the new entity denotes the base type (s) of
3850 -- the types given in the specification. For access parameters
3851 -- there are no subtypes involved.
3853 Rewrite
(Parameter_Type
(Param_Spec
),
3855 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3858 if No
(Expr_List
) then
3859 Expr_List
:= New_List
;
3862 Append_To
(Expr_List
,
3863 Make_Identifier
(Loc
,
3864 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3866 -- The expressions in the attribute reference are not freeze
3867 -- points. Neither is the attribute as a whole, see below.
3869 Set_Must_Not_Freeze
(Last
(Expr_List
));
3874 -- Immediate error if too many formals. Other mismatches in number or
3875 -- types of parameters are detected when we analyze the body of the
3876 -- subprogram that we construct.
3878 if Form_Num
> 2 then
3879 Error_Msg_N
("too many formals for attribute", N
);
3881 -- Error if the attribute reference has expressions that look like
3882 -- formal parameters.
3884 elsif Present
(Expressions
(Nam
)) then
3885 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3888 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3889 Name_Pos
, Name_Round
, Name_Scaling
,
3892 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3893 and then Present
(Corresponding_Formal_Spec
(N
))
3896 ("generic actual cannot be attribute involving universal type",
3900 ("attribute involving a universal type cannot be renamed",
3905 -- Rewrite attribute node to have a list of expressions corresponding to
3906 -- the subprogram formals. A renaming declaration is not a freeze point,
3907 -- and the analysis of the attribute reference should not freeze the
3908 -- type of the prefix. We use the original node in the renaming so that
3909 -- its source location is preserved, and checks on stream attributes are
3910 -- properly applied.
3912 Attr_Node
:= Relocate_Node
(Nam
);
3913 Set_Expressions
(Attr_Node
, Expr_List
);
3915 Set_Must_Not_Freeze
(Attr_Node
);
3916 Set_Must_Not_Freeze
(Prefix
(Nam
));
3918 -- Case of renaming a function
3920 if Nkind
(Spec
) = N_Function_Specification
then
3921 if Is_Procedure_Attribute_Name
(Aname
) then
3922 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3926 Find_Type
(Result_Definition
(Spec
));
3927 Rewrite
(Result_Definition
(Spec
),
3929 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3932 Make_Subprogram_Body
(Loc
,
3933 Specification
=> Spec
,
3934 Declarations
=> New_List
,
3935 Handled_Statement_Sequence
=>
3936 Make_Handled_Sequence_Of_Statements
(Loc
,
3937 Statements
=> New_List
(
3938 Make_Simple_Return_Statement
(Loc
,
3939 Expression
=> Attr_Node
))));
3941 -- Case of renaming a procedure
3944 if not Is_Procedure_Attribute_Name
(Aname
) then
3945 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3950 Make_Subprogram_Body
(Loc
,
3951 Specification
=> Spec
,
3952 Declarations
=> New_List
,
3953 Handled_Statement_Sequence
=>
3954 Make_Handled_Sequence_Of_Statements
(Loc
,
3955 Statements
=> New_List
(Attr_Node
)));
3958 -- In case of tagged types we add the body of the generated function to
3959 -- the freezing actions of the type (because in the general case such
3960 -- type is still not frozen). We exclude from this processing generic
3961 -- formal subprograms found in instantiations.
3963 -- We must exclude VM targets and restricted run-time libraries because
3964 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3965 -- available in those platforms. Note that we cannot use the function
3966 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3967 -- the ZFP run-time library is not defined as a profile, and we do not
3968 -- want to deal with AST_Handler in ZFP mode.
3970 if VM_Target
= No_VM
3971 and then not Configurable_Run_Time_Mode
3972 and then not Present
(Corresponding_Formal_Spec
(N
))
3973 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
3976 P
: constant Node_Id
:= Prefix
(Nam
);
3979 -- The prefix of 'Img is an object that is evaluated for each call
3980 -- of the function that renames it.
3982 if Aname
= Name_Img
then
3983 Preanalyze_And_Resolve
(P
);
3985 -- For all other attribute renamings, the prefix is a subtype
3991 -- If the target type is not yet frozen, add the body to the
3992 -- actions to be elaborated at freeze time.
3994 if Is_Tagged_Type
(Etype
(P
))
3995 and then In_Open_Scopes
(Scope
(Etype
(P
)))
3997 Ensure_Freeze_Node
(Etype
(P
));
3998 Append_Freeze_Action
(Etype
(P
), Body_Node
);
4000 Rewrite
(N
, Body_Node
);
4002 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4006 -- Generic formal subprograms or AST_Handler renaming
4009 Rewrite
(N
, Body_Node
);
4011 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4014 if Is_Compilation_Unit
(New_S
) then
4016 ("a library unit can only rename another library unit", N
);
4019 -- We suppress elaboration warnings for the resulting entity, since
4020 -- clearly they are not needed, and more particularly, in the case
4021 -- of a generic formal subprogram, the resulting entity can appear
4022 -- after the instantiation itself, and thus look like a bogus case
4023 -- of access before elaboration.
4025 Set_Suppress_Elaboration_Warnings
(New_S
);
4027 end Attribute_Renaming
;
4029 ----------------------
4030 -- Chain_Use_Clause --
4031 ----------------------
4033 procedure Chain_Use_Clause
(N
: Node_Id
) is
4035 Level
: Int
:= Scope_Stack
.Last
;
4038 if not Is_Compilation_Unit
(Current_Scope
)
4039 or else not Is_Child_Unit
(Current_Scope
)
4041 null; -- Common case
4043 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
4044 null; -- Common case for compilation unit
4047 -- If declaration appears in some other scope, it must be in some
4048 -- parent unit when compiling a child.
4050 Pack
:= Defining_Entity
(Parent
(N
));
4051 if not In_Open_Scopes
(Pack
) then
4052 null; -- default as well
4054 -- If the use clause appears in an ancestor and we are in the
4055 -- private part of the immediate parent, the use clauses are
4056 -- already installed.
4058 elsif Pack
/= Scope
(Current_Scope
)
4059 and then In_Private_Part
(Scope
(Current_Scope
))
4064 -- Find entry for parent unit in scope stack
4066 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4072 Set_Next_Use_Clause
(N
,
4073 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4074 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4075 end Chain_Use_Clause
;
4077 ---------------------------
4078 -- Check_Frozen_Renaming --
4079 ---------------------------
4081 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4086 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4089 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4091 if Is_Entity_Name
(Name
(N
)) then
4092 Old_S
:= Entity
(Name
(N
));
4094 if not Is_Frozen
(Old_S
)
4095 and then Operating_Mode
/= Check_Semantics
4097 Append_Freeze_Action
(Old_S
, B_Node
);
4099 Insert_After
(N
, B_Node
);
4103 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4105 ("subprogram used in renaming_as_body cannot be intrinsic",
4110 Insert_After
(N
, B_Node
);
4114 end Check_Frozen_Renaming
;
4116 -------------------------------
4117 -- Set_Entity_Or_Discriminal --
4118 -------------------------------
4120 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4124 -- If the entity is not a discriminant, or else expansion is disabled,
4125 -- simply set the entity.
4127 if not In_Spec_Expression
4128 or else Ekind
(E
) /= E_Discriminant
4129 or else Inside_A_Generic
4131 Set_Entity_With_Checks
(N
, E
);
4133 -- The replacement of a discriminant by the corresponding discriminal
4134 -- is not done for a task discriminant that appears in a default
4135 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4136 -- for details on their handling.
4138 elsif Is_Concurrent_Type
(Scope
(E
)) then
4141 and then not Nkind_In
(P
, N_Parameter_Specification
,
4142 N_Component_Declaration
)
4148 and then Nkind
(P
) = N_Parameter_Specification
4153 Set_Entity
(N
, Discriminal
(E
));
4156 -- Otherwise, this is a discriminant in a context in which
4157 -- it is a reference to the corresponding parameter of the
4158 -- init proc for the enclosing type.
4161 Set_Entity
(N
, Discriminal
(E
));
4163 end Set_Entity_Or_Discriminal
;
4165 -----------------------------------
4166 -- Check_In_Previous_With_Clause --
4167 -----------------------------------
4169 procedure Check_In_Previous_With_Clause
4173 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4178 Item
:= First
(Context_Items
(Parent
(N
)));
4179 while Present
(Item
) and then Item
/= N
loop
4180 if Nkind
(Item
) = N_With_Clause
4182 -- Protect the frontend against previous critical errors
4184 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4185 and then Entity
(Name
(Item
)) = Pack
4189 -- Find root library unit in with_clause
4191 while Nkind
(Par
) = N_Expanded_Name
loop
4192 Par
:= Prefix
(Par
);
4195 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4196 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4205 -- On exit, package is not mentioned in a previous with_clause.
4206 -- Check if its prefix is.
4208 if Nkind
(Nam
) = N_Expanded_Name
then
4209 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4211 elsif Pack
/= Any_Id
then
4212 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4214 end Check_In_Previous_With_Clause
;
4216 ---------------------------------
4217 -- Check_Library_Unit_Renaming --
4218 ---------------------------------
4220 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4224 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4227 -- Check for library unit. Note that we used to check for the scope
4228 -- being Standard here, but that was wrong for Standard itself.
4230 elsif not Is_Compilation_Unit
(Old_E
)
4231 and then not Is_Child_Unit
(Old_E
)
4233 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4235 -- Entities defined in Standard (operators and boolean literals) cannot
4236 -- be renamed as library units.
4238 elsif Scope
(Old_E
) = Standard_Standard
4239 and then Sloc
(Old_E
) = Standard_Location
4241 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4243 elsif Present
(Parent_Spec
(N
))
4244 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4245 and then not Is_Child_Unit
(Old_E
)
4248 ("renamed unit must be a child unit of generic parent", Name
(N
));
4250 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4251 and then Nkind
(Name
(N
)) = N_Expanded_Name
4252 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4253 and then Is_Generic_Unit
(Old_E
)
4256 ("renamed generic unit must be a library unit", Name
(N
));
4258 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4260 -- Inherit categorization flags
4262 New_E
:= Defining_Entity
(N
);
4263 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4264 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4265 Set_Is_Remote_Call_Interface
(New_E
,
4266 Is_Remote_Call_Interface
(Old_E
));
4267 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4268 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4270 end Check_Library_Unit_Renaming
;
4272 ------------------------
4273 -- Enclosing_Instance --
4274 ------------------------
4276 function Enclosing_Instance
return Entity_Id
is
4280 if not Is_Generic_Instance
(Current_Scope
) then
4284 S
:= Scope
(Current_Scope
);
4285 while S
/= Standard_Standard
loop
4286 if Is_Generic_Instance
(S
) then
4294 end Enclosing_Instance
;
4300 procedure End_Scope
is
4306 Id
:= First_Entity
(Current_Scope
);
4307 while Present
(Id
) loop
4308 -- An entity in the current scope is not necessarily the first one
4309 -- on its homonym chain. Find its predecessor if any,
4310 -- If it is an internal entity, it will not be in the visibility
4311 -- chain altogether, and there is nothing to unchain.
4313 if Id
/= Current_Entity
(Id
) then
4314 Prev
:= Current_Entity
(Id
);
4315 while Present
(Prev
)
4316 and then Present
(Homonym
(Prev
))
4317 and then Homonym
(Prev
) /= Id
4319 Prev
:= Homonym
(Prev
);
4322 -- Skip to end of loop if Id is not in the visibility chain
4324 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4332 Set_Is_Immediately_Visible
(Id
, False);
4334 Outer
:= Homonym
(Id
);
4335 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4336 Outer
:= Homonym
(Outer
);
4339 -- Reset homonym link of other entities, but do not modify link
4340 -- between entities in current scope, so that the back-end can have
4341 -- a proper count of local overloadings.
4344 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4346 elsif Scope
(Prev
) /= Scope
(Id
) then
4347 Set_Homonym
(Prev
, Outer
);
4354 -- If the scope generated freeze actions, place them before the
4355 -- current declaration and analyze them. Type declarations and
4356 -- the bodies of initialization procedures can generate such nodes.
4357 -- We follow the parent chain until we reach a list node, which is
4358 -- the enclosing list of declarations. If the list appears within
4359 -- a protected definition, move freeze nodes outside the protected
4363 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4367 L
: constant List_Id
:= Scope_Stack
.Table
4368 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4371 if Is_Itype
(Current_Scope
) then
4372 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4374 Decl
:= Parent
(Current_Scope
);
4379 while not (Is_List_Member
(Decl
))
4380 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4383 Decl
:= Parent
(Decl
);
4386 Insert_List_Before_And_Analyze
(Decl
, L
);
4394 ---------------------
4395 -- End_Use_Clauses --
4396 ---------------------
4398 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4402 -- Remove Use_Type clauses first, because they affect the
4403 -- visibility of operators in subsequent used packages.
4406 while Present
(U
) loop
4407 if Nkind
(U
) = N_Use_Type_Clause
then
4411 Next_Use_Clause
(U
);
4415 while Present
(U
) loop
4416 if Nkind
(U
) = N_Use_Package_Clause
then
4417 End_Use_Package
(U
);
4420 Next_Use_Clause
(U
);
4422 end End_Use_Clauses
;
4424 ---------------------
4425 -- End_Use_Package --
4426 ---------------------
4428 procedure End_Use_Package
(N
: Node_Id
) is
4429 Pack_Name
: Node_Id
;
4434 function Is_Primitive_Operator_In_Use
4436 F
: Entity_Id
) return Boolean;
4437 -- Check whether Op is a primitive operator of a use-visible type
4439 ----------------------------------
4440 -- Is_Primitive_Operator_In_Use --
4441 ----------------------------------
4443 function Is_Primitive_Operator_In_Use
4445 F
: Entity_Id
) return Boolean
4447 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4449 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4450 end Is_Primitive_Operator_In_Use
;
4452 -- Start of processing for End_Use_Package
4455 Pack_Name
:= First
(Names
(N
));
4456 while Present
(Pack_Name
) loop
4458 -- Test that Pack_Name actually denotes a package before processing
4460 if Is_Entity_Name
(Pack_Name
)
4461 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4463 Pack
:= Entity
(Pack_Name
);
4465 if In_Open_Scopes
(Pack
) then
4468 elsif not Redundant_Use
(Pack_Name
) then
4469 Set_In_Use
(Pack
, False);
4470 Set_Current_Use_Clause
(Pack
, Empty
);
4472 Id
:= First_Entity
(Pack
);
4473 while Present
(Id
) loop
4475 -- Preserve use-visibility of operators that are primitive
4476 -- operators of a type that is use-visible through an active
4479 if Nkind
(Id
) = N_Defining_Operator_Symbol
4481 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4483 (Present
(Next_Formal
(First_Formal
(Id
)))
4485 Is_Primitive_Operator_In_Use
4486 (Id
, Next_Formal
(First_Formal
(Id
)))))
4490 Set_Is_Potentially_Use_Visible
(Id
, False);
4493 if Is_Private_Type
(Id
)
4494 and then Present
(Full_View
(Id
))
4496 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4502 if Present
(Renamed_Object
(Pack
)) then
4503 Set_In_Use
(Renamed_Object
(Pack
), False);
4504 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4507 if Chars
(Pack
) = Name_System
4508 and then Scope
(Pack
) = Standard_Standard
4509 and then Present_System_Aux
4511 Id
:= First_Entity
(System_Aux_Id
);
4512 while Present
(Id
) loop
4513 Set_Is_Potentially_Use_Visible
(Id
, False);
4515 if Is_Private_Type
(Id
)
4516 and then Present
(Full_View
(Id
))
4518 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4524 Set_In_Use
(System_Aux_Id
, False);
4528 Set_Redundant_Use
(Pack_Name
, False);
4535 if Present
(Hidden_By_Use_Clause
(N
)) then
4536 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4537 while Present
(Elmt
) loop
4539 E
: constant Entity_Id
:= Node
(Elmt
);
4542 -- Reset either Use_Visibility or Direct_Visibility, depending
4543 -- on how the entity was hidden by the use clause.
4545 if In_Use
(Scope
(E
))
4546 and then Used_As_Generic_Actual
(Scope
(E
))
4548 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4550 Set_Is_Immediately_Visible
(Node
(Elmt
));
4557 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4559 end End_Use_Package
;
4565 procedure End_Use_Type
(N
: Node_Id
) is
4570 -- Start of processing for End_Use_Type
4573 Id
:= First
(Subtype_Marks
(N
));
4574 while Present
(Id
) loop
4576 -- A call to Rtsfind may occur while analyzing a use_type clause,
4577 -- in which case the type marks are not resolved yet, and there is
4578 -- nothing to remove.
4580 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4586 if T
= Any_Type
or else From_Limited_With
(T
) then
4589 -- Note that the use_type clause may mention a subtype of the type
4590 -- whose primitive operations have been made visible. Here as
4591 -- elsewhere, it is the base type that matters for visibility.
4593 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4596 elsif not Redundant_Use
(Id
) then
4597 Set_In_Use
(T
, False);
4598 Set_In_Use
(Base_Type
(T
), False);
4599 Set_Current_Use_Clause
(T
, Empty
);
4600 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4607 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4611 Elmt
:= First_Elmt
(Used_Operations
(N
));
4612 while Present
(Elmt
) loop
4613 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4619 ----------------------
4620 -- Find_Direct_Name --
4621 ----------------------
4623 procedure Find_Direct_Name
(N
: Node_Id
) is
4628 Inst
: Entity_Id
:= Empty
;
4629 -- Enclosing instance, if any
4631 Homonyms
: Entity_Id
;
4632 -- Saves start of homonym chain
4634 Nvis_Entity
: Boolean;
4635 -- Set True to indicate that there is at least one entity on the homonym
4636 -- chain which, while not visible, is visible enough from the user point
4637 -- of view to warrant an error message of "not visible" rather than
4640 Nvis_Is_Private_Subprg
: Boolean := False;
4641 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4642 -- effect concerning library subprograms has been detected. Used to
4643 -- generate the precise error message.
4645 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4646 -- Returns true if the entity is an actual for a package that is itself
4647 -- an actual for a formal package of the current instance. Such an
4648 -- entity requires special handling because it may be use-visible but
4649 -- hides directly visible entities defined outside the instance, because
4650 -- the corresponding formal did so in the generic.
4652 function Is_Actual_Parameter
return Boolean;
4653 -- This function checks if the node N is an identifier that is an actual
4654 -- parameter of a procedure call. If so it returns True, otherwise it
4655 -- return False. The reason for this check is that at this stage we do
4656 -- not know what procedure is being called if the procedure might be
4657 -- overloaded, so it is premature to go setting referenced flags or
4658 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4659 -- for that processing
4661 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4662 -- This function determines whether a reference to the entity E, which
4663 -- is not visible, can reasonably be considered to be known to the
4664 -- writer of the reference. This is a heuristic test, used only for
4665 -- the purposes of figuring out whether we prefer to complain that an
4666 -- entity is undefined or invisible (and identify the declaration of
4667 -- the invisible entity in the latter case). The point here is that we
4668 -- don't want to complain that something is invisible and then point to
4669 -- something entirely mysterious to the writer.
4671 procedure Nvis_Messages
;
4672 -- Called if there are no visible entries for N, but there is at least
4673 -- one non-directly visible, or hidden declaration. This procedure
4674 -- outputs an appropriate set of error messages.
4676 procedure Undefined
(Nvis
: Boolean);
4677 -- This function is called if the current node has no corresponding
4678 -- visible entity or entities. The value set in Msg indicates whether
4679 -- an error message was generated (multiple error messages for the
4680 -- same variable are generally suppressed, see body for details).
4681 -- Msg is True if an error message was generated, False if not. This
4682 -- value is used by the caller to determine whether or not to output
4683 -- additional messages where appropriate. The parameter is set False
4684 -- to get the message "X is undefined", and True to get the message
4685 -- "X is not visible".
4687 -------------------------
4688 -- From_Actual_Package --
4689 -------------------------
4691 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4692 Scop
: constant Entity_Id
:= Scope
(E
);
4693 -- Declared scope of candidate entity
4697 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4698 -- Recursive function that does the work and examines actuals of
4699 -- actual packages of current instance.
4701 ------------------------
4702 -- Declared_In_Actual --
4703 ------------------------
4705 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4709 if No
(Associated_Formal_Package
(Pack
)) then
4713 Act
:= First_Entity
(Pack
);
4714 while Present
(Act
) loop
4715 if Renamed_Object
(Pack
) = Scop
then
4718 -- Check for end of list of actuals.
4720 elsif Ekind
(Act
) = E_Package
4721 and then Renamed_Object
(Act
) = Pack
4725 elsif Ekind
(Act
) = E_Package
4726 and then Declared_In_Actual
(Act
)
4736 end Declared_In_Actual
;
4738 -- Start of processing for From_Actual_Package
4741 if not In_Instance
then
4745 Inst
:= Current_Scope
;
4746 while Present
(Inst
)
4747 and then Ekind
(Inst
) /= E_Package
4748 and then not Is_Generic_Instance
(Inst
)
4750 Inst
:= Scope
(Inst
);
4757 Act
:= First_Entity
(Inst
);
4758 while Present
(Act
) loop
4759 if Ekind
(Act
) = E_Package
4760 and then Declared_In_Actual
(Act
)
4770 end From_Actual_Package
;
4772 -------------------------
4773 -- Is_Actual_Parameter --
4774 -------------------------
4776 function Is_Actual_Parameter
return Boolean is
4779 Nkind
(N
) = N_Identifier
4781 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4783 (Nkind
(Parent
(N
)) = N_Parameter_Association
4784 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4785 and then Nkind
(Parent
(Parent
(N
))) =
4786 N_Procedure_Call_Statement
));
4787 end Is_Actual_Parameter
;
4789 -------------------------
4790 -- Known_But_Invisible --
4791 -------------------------
4793 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4794 Fname
: File_Name_Type
;
4797 -- Entities in Standard are always considered to be known
4799 if Sloc
(E
) <= Standard_Location
then
4802 -- An entity that does not come from source is always considered
4803 -- to be unknown, since it is an artifact of code expansion.
4805 elsif not Comes_From_Source
(E
) then
4808 -- In gnat internal mode, we consider all entities known. The
4809 -- historical reason behind this discrepancy is not known??? But the
4810 -- only effect is to modify the error message given, so it is not
4811 -- critical. Since it only affects the exact wording of error
4812 -- messages in illegal programs, we do not mention this as an
4813 -- effect of -gnatg, since it is not a language modification.
4815 elsif GNAT_Mode
then
4819 -- Here we have an entity that is not from package Standard, and
4820 -- which comes from Source. See if it comes from an internal file.
4822 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4824 -- Case of from internal file
4826 if Is_Internal_File_Name
(Fname
) then
4828 -- Private part entities in internal files are never considered
4829 -- to be known to the writer of normal application code.
4831 if Is_Hidden
(E
) then
4835 -- Entities from System packages other than System and
4836 -- System.Storage_Elements are not considered to be known.
4837 -- System.Auxxxx files are also considered known to the user.
4839 -- Should refine this at some point to generally distinguish
4840 -- between known and unknown internal files ???
4842 Get_Name_String
(Fname
);
4847 Name_Buffer
(1 .. 2) /= "s-"
4849 Name_Buffer
(3 .. 8) = "stoele"
4851 Name_Buffer
(3 .. 5) = "aux";
4853 -- If not an internal file, then entity is definitely known,
4854 -- even if it is in a private part (the message generated will
4855 -- note that it is in a private part)
4860 end Known_But_Invisible
;
4866 procedure Nvis_Messages
is
4867 Comp_Unit
: Node_Id
;
4869 Found
: Boolean := False;
4870 Hidden
: Boolean := False;
4874 -- Ada 2005 (AI-262): Generate a precise error concerning the
4875 -- Beaujolais effect that was previously detected
4877 if Nvis_Is_Private_Subprg
then
4879 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4880 and then Ekind
(E2
) = E_Function
4881 and then Scope
(E2
) = Standard_Standard
4882 and then Has_Private_With
(E2
));
4884 -- Find the sloc corresponding to the private with'ed unit
4886 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4887 Error_Msg_Sloc
:= No_Location
;
4889 Item
:= First
(Context_Items
(Comp_Unit
));
4890 while Present
(Item
) loop
4891 if Nkind
(Item
) = N_With_Clause
4892 and then Private_Present
(Item
)
4893 and then Entity
(Name
(Item
)) = E2
4895 Error_Msg_Sloc
:= Sloc
(Item
);
4902 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4904 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4908 Undefined
(Nvis
=> True);
4912 -- First loop does hidden declarations
4915 while Present
(Ent
) loop
4916 if Is_Potentially_Use_Visible
(Ent
) then
4918 Error_Msg_N
-- CODEFIX
4919 ("multiple use clauses cause hiding!", N
);
4923 Error_Msg_Sloc
:= Sloc
(Ent
);
4924 Error_Msg_N
-- CODEFIX
4925 ("hidden declaration#!", N
);
4928 Ent
:= Homonym
(Ent
);
4931 -- If we found hidden declarations, then that's enough, don't
4932 -- bother looking for non-visible declarations as well.
4938 -- Second loop does non-directly visible declarations
4941 while Present
(Ent
) loop
4942 if not Is_Potentially_Use_Visible
(Ent
) then
4944 -- Do not bother the user with unknown entities
4946 if not Known_But_Invisible
(Ent
) then
4950 Error_Msg_Sloc
:= Sloc
(Ent
);
4952 -- Output message noting that there is a non-visible
4953 -- declaration, distinguishing the private part case.
4955 if Is_Hidden
(Ent
) then
4956 Error_Msg_N
("non-visible (private) declaration#!", N
);
4958 -- If the entity is declared in a generic package, it
4959 -- cannot be visible, so there is no point in adding it
4960 -- to the list of candidates if another homograph from a
4961 -- non-generic package has been seen.
4963 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4969 Error_Msg_N
-- CODEFIX
4970 ("non-visible declaration#!", N
);
4972 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
4976 if Is_Compilation_Unit
(Ent
)
4978 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
4980 Error_Msg_Qual_Level
:= 99;
4981 Error_Msg_NE
-- CODEFIX
4982 ("\\missing `WITH &;`", N
, Ent
);
4983 Error_Msg_Qual_Level
:= 0;
4986 if Ekind
(Ent
) = E_Discriminant
4987 and then Present
(Corresponding_Discriminant
(Ent
))
4988 and then Scope
(Corresponding_Discriminant
(Ent
)) =
4992 ("inherited discriminant not allowed here" &
4993 " (RM 3.8 (12), 3.8.1 (6))!", N
);
4997 -- Set entity and its containing package as referenced. We
4998 -- can't be sure of this, but this seems a better choice
4999 -- to avoid unused entity messages.
5001 if Comes_From_Source
(Ent
) then
5002 Set_Referenced
(Ent
);
5003 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
5008 Ent
:= Homonym
(Ent
);
5017 procedure Undefined
(Nvis
: Boolean) is
5018 Emsg
: Error_Msg_Id
;
5021 -- We should never find an undefined internal name. If we do, then
5022 -- see if we have previous errors. If so, ignore on the grounds that
5023 -- it is probably a cascaded message (e.g. a block label from a badly
5024 -- formed block). If no previous errors, then we have a real internal
5025 -- error of some kind so raise an exception.
5027 if Is_Internal_Name
(Chars
(N
)) then
5028 if Total_Errors_Detected
/= 0 then
5031 raise Program_Error
;
5035 -- A very specialized error check, if the undefined variable is
5036 -- a case tag, and the case type is an enumeration type, check
5037 -- for a possible misspelling, and if so, modify the identifier
5039 -- Named aggregate should also be handled similarly ???
5041 if Nkind
(N
) = N_Identifier
5042 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5045 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5046 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5051 if Is_Enumeration_Type
(Case_Typ
)
5052 and then not Is_Standard_Character_Type
(Case_Typ
)
5054 Lit
:= First_Literal
(Case_Typ
);
5055 Get_Name_String
(Chars
(Lit
));
5057 if Chars
(Lit
) /= Chars
(N
)
5058 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5060 Error_Msg_Node_2
:= Lit
;
5061 Error_Msg_N
-- CODEFIX
5062 ("& is undefined, assume misspelling of &", N
);
5063 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5067 Lit
:= Next_Literal
(Lit
);
5072 -- Normal processing
5074 Set_Entity
(N
, Any_Id
);
5075 Set_Etype
(N
, Any_Type
);
5077 -- We use the table Urefs to keep track of entities for which we
5078 -- have issued errors for undefined references. Multiple errors
5079 -- for a single name are normally suppressed, however we modify
5080 -- the error message to alert the programmer to this effect.
5082 for J
in Urefs
.First
.. Urefs
.Last
loop
5083 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5084 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5085 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5087 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5089 if Urefs
.Table
(J
).Nvis
then
5090 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5091 "& is not visible (more references follow)");
5093 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5094 "& is undefined (more references follow)");
5097 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5100 -- Although we will set Msg False, and thus suppress the
5101 -- message, we also set Error_Posted True, to avoid any
5102 -- cascaded messages resulting from the undefined reference.
5105 Set_Error_Posted
(N
, True);
5110 -- If entry not found, this is first undefined occurrence
5113 Error_Msg_N
("& is not visible!", N
);
5117 Error_Msg_N
("& is undefined!", N
);
5120 -- A very bizarre special check, if the undefined identifier
5121 -- is put or put_line, then add a special error message (since
5122 -- this is a very common error for beginners to make).
5124 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5125 Error_Msg_N
-- CODEFIX
5126 ("\\possible missing `WITH Ada.Text_'I'O; " &
5127 "USE Ada.Text_'I'O`!", N
);
5129 -- Another special check if N is the prefix of a selected
5130 -- component which is a known unit, add message complaining
5131 -- about missing with for this unit.
5133 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5134 and then N
= Prefix
(Parent
(N
))
5135 and then Is_Known_Unit
(Parent
(N
))
5137 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5138 Error_Msg_N
-- CODEFIX
5139 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5142 -- Now check for possible misspellings
5146 Ematch
: Entity_Id
:= Empty
;
5148 Last_Name_Id
: constant Name_Id
:=
5149 Name_Id
(Nat
(First_Name_Id
) +
5150 Name_Entries_Count
- 1);
5153 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5154 E
:= Get_Name_Entity_Id
(Nam
);
5157 and then (Is_Immediately_Visible
(E
)
5159 Is_Potentially_Use_Visible
(E
))
5161 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5168 if Present
(Ematch
) then
5169 Error_Msg_NE
-- CODEFIX
5170 ("\possible misspelling of&", N
, Ematch
);
5175 -- Make entry in undefined references table unless the full errors
5176 -- switch is set, in which case by refraining from generating the
5177 -- table entry, we guarantee that we get an error message for every
5178 -- undefined reference.
5180 if not All_Errors_Mode
then
5191 -- Start of processing for Find_Direct_Name
5194 -- If the entity pointer is already set, this is an internal node, or
5195 -- a node that is analyzed more than once, after a tree modification.
5196 -- In such a case there is no resolution to perform, just set the type.
5198 if Present
(Entity
(N
)) then
5199 if Is_Type
(Entity
(N
)) then
5200 Set_Etype
(N
, Entity
(N
));
5204 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5207 -- One special case here. If the Etype field is already set,
5208 -- and references the packed array type corresponding to the
5209 -- etype of the referenced entity, then leave it alone. This
5210 -- happens for trees generated from Exp_Pakd, where expressions
5211 -- can be deliberately "mis-typed" to the packed array type.
5213 if Is_Array_Type
(Entyp
)
5214 and then Is_Packed
(Entyp
)
5215 and then Present
(Etype
(N
))
5216 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5220 -- If not that special case, then just reset the Etype
5223 Set_Etype
(N
, Etype
(Entity
(N
)));
5231 -- Here if Entity pointer was not set, we need full visibility analysis
5232 -- First we generate debugging output if the debug E flag is set.
5234 if Debug_Flag_E
then
5235 Write_Str
("Looking for ");
5236 Write_Name
(Chars
(N
));
5240 Homonyms
:= Current_Entity
(N
);
5241 Nvis_Entity
:= False;
5244 while Present
(E
) loop
5246 -- If entity is immediately visible or potentially use visible, then
5247 -- process the entity and we are done.
5249 if Is_Immediately_Visible
(E
) then
5250 goto Immediately_Visible_Entity
;
5252 elsif Is_Potentially_Use_Visible
(E
) then
5253 goto Potentially_Use_Visible_Entity
;
5255 -- Note if a known but invisible entity encountered
5257 elsif Known_But_Invisible
(E
) then
5258 Nvis_Entity
:= True;
5261 -- Move to next entity in chain and continue search
5266 -- If no entries on homonym chain that were potentially visible,
5267 -- and no entities reasonably considered as non-visible, then
5268 -- we have a plain undefined reference, with no additional
5269 -- explanation required.
5271 if not Nvis_Entity
then
5272 Undefined
(Nvis
=> False);
5274 -- Otherwise there is at least one entry on the homonym chain that
5275 -- is reasonably considered as being known and non-visible.
5283 -- Processing for a potentially use visible entry found. We must search
5284 -- the rest of the homonym chain for two reasons. First, if there is a
5285 -- directly visible entry, then none of the potentially use-visible
5286 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5287 -- for the case of multiple potentially use-visible entries hiding one
5288 -- another and as a result being non-directly visible (RM 8.4(11)).
5290 <<Potentially_Use_Visible_Entity
>> declare
5291 Only_One_Visible
: Boolean := True;
5292 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5296 while Present
(E2
) loop
5297 if Is_Immediately_Visible
(E2
) then
5299 -- If the use-visible entity comes from the actual for a
5300 -- formal package, it hides a directly visible entity from
5301 -- outside the instance.
5303 if From_Actual_Package
(E
)
5304 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5309 goto Immediately_Visible_Entity
;
5312 elsif Is_Potentially_Use_Visible
(E2
) then
5313 Only_One_Visible
:= False;
5314 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5316 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5317 -- that can occur in private_with clauses. Example:
5320 -- private with B; package A is
5321 -- package C is function B return Integer;
5323 -- V1 : Integer := B;
5324 -- private function B return Integer;
5325 -- V2 : Integer := B;
5328 -- V1 resolves to A.B, but V2 resolves to library unit B
5330 elsif Ekind
(E2
) = E_Function
5331 and then Scope
(E2
) = Standard_Standard
5332 and then Has_Private_With
(E2
)
5334 Only_One_Visible
:= False;
5335 All_Overloadable
:= False;
5336 Nvis_Is_Private_Subprg
:= True;
5343 -- On falling through this loop, we have checked that there are no
5344 -- immediately visible entities. Only_One_Visible is set if exactly
5345 -- one potentially use visible entity exists. All_Overloadable is
5346 -- set if all the potentially use visible entities are overloadable.
5347 -- The condition for legality is that either there is one potentially
5348 -- use visible entity, or if there is more than one, then all of them
5349 -- are overloadable.
5351 if Only_One_Visible
or All_Overloadable
then
5354 -- If there is more than one potentially use-visible entity and at
5355 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5356 -- Note that E points to the first such entity on the homonym list.
5357 -- Special case: if one of the entities is declared in an actual
5358 -- package, it was visible in the generic, and takes precedence over
5359 -- other entities that are potentially use-visible. Same if it is
5360 -- declared in a local instantiation of the current instance.
5365 -- Find current instance
5367 Inst
:= Current_Scope
;
5368 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5369 if Is_Generic_Instance
(Inst
) then
5373 Inst
:= Scope
(Inst
);
5377 while Present
(E2
) loop
5378 if From_Actual_Package
(E2
)
5380 (Is_Generic_Instance
(Scope
(E2
))
5381 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5394 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5396 -- A use-clause in the body of a system file creates conflict
5397 -- with some entity in a user scope, while rtsfind is active.
5398 -- Keep only the entity coming from another predefined unit.
5401 while Present
(E2
) loop
5402 if Is_Predefined_File_Name
5403 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5412 -- Entity must exist because predefined unit is correct
5414 raise Program_Error
;
5423 -- Come here with E set to the first immediately visible entity on
5424 -- the homonym chain. This is the one we want unless there is another
5425 -- immediately visible entity further on in the chain for an inner
5426 -- scope (RM 8.3(8)).
5428 <<Immediately_Visible_Entity
>> declare
5433 -- Find scope level of initial entity. When compiling through
5434 -- Rtsfind, the previous context is not completely invisible, and
5435 -- an outer entity may appear on the chain, whose scope is below
5436 -- the entry for Standard that delimits the current scope stack.
5437 -- Indicate that the level for this spurious entry is outside of
5438 -- the current scope stack.
5440 Level
:= Scope_Stack
.Last
;
5442 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5443 exit when Scop
= Scope
(E
);
5445 exit when Scop
= Standard_Standard
;
5448 -- Now search remainder of homonym chain for more inner entry
5449 -- If the entity is Standard itself, it has no scope, and we
5450 -- compare it with the stack entry directly.
5453 while Present
(E2
) loop
5454 if Is_Immediately_Visible
(E2
) then
5456 -- If a generic package contains a local declaration that
5457 -- has the same name as the generic, there may be a visibility
5458 -- conflict in an instance, where the local declaration must
5459 -- also hide the name of the corresponding package renaming.
5460 -- We check explicitly for a package declared by a renaming,
5461 -- whose renamed entity is an instance that is on the scope
5462 -- stack, and that contains a homonym in the same scope. Once
5463 -- we have found it, we know that the package renaming is not
5464 -- immediately visible, and that the identifier denotes the
5465 -- other entity (and its homonyms if overloaded).
5467 if Scope
(E
) = Scope
(E2
)
5468 and then Ekind
(E
) = E_Package
5469 and then Present
(Renamed_Object
(E
))
5470 and then Is_Generic_Instance
(Renamed_Object
(E
))
5471 and then In_Open_Scopes
(Renamed_Object
(E
))
5472 and then Comes_From_Source
(N
)
5474 Set_Is_Immediately_Visible
(E
, False);
5478 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5479 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5480 or else Scope_Stack
.Table
(J
).Entity
= E2
5493 -- At the end of that loop, E is the innermost immediately
5494 -- visible entity, so we are all set.
5497 -- Come here with entity found, and stored in E
5501 -- Check violation of No_Wide_Characters restriction
5503 Check_Wide_Character_Restriction
(E
, N
);
5505 -- When distribution features are available (Get_PCS_Name /=
5506 -- Name_No_DSA), a remote access-to-subprogram type is converted
5507 -- into a record type holding whatever information is needed to
5508 -- perform a remote call on an RCI subprogram. In that case we
5509 -- rewrite any occurrence of the RAS type into the equivalent record
5510 -- type here. 'Access attribute references and RAS dereferences are
5511 -- then implemented using specific TSSs. However when distribution is
5512 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5513 -- generation of these TSSs, and we must keep the RAS type in its
5514 -- original access-to-subprogram form (since all calls through a
5515 -- value of such type will be local anyway in the absence of a PCS).
5517 if Comes_From_Source
(N
)
5518 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5519 and then Ekind
(E
) = E_Access_Subprogram_Type
5520 and then Expander_Active
5521 and then Get_PCS_Name
/= Name_No_DSA
5523 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5527 -- Set the entity. Note that the reason we call Set_Entity for the
5528 -- overloadable case, as opposed to Set_Entity_With_Checks is
5529 -- that in the overloaded case, the initial call can set the wrong
5530 -- homonym. The call that sets the right homonym is in Sem_Res and
5531 -- that call does use Set_Entity_With_Checks, so we don't miss
5534 if Is_Overloadable
(E
) then
5537 Set_Entity_With_Checks
(N
, E
);
5543 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5546 if Debug_Flag_E
then
5547 Write_Str
(" found ");
5548 Write_Entity_Info
(E
, " ");
5551 -- If the Ekind of the entity is Void, it means that all homonyms
5552 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5553 -- test is skipped if the current scope is a record and the name is
5554 -- a pragma argument expression (case of Atomic and Volatile pragmas
5555 -- and possibly other similar pragmas added later, which are allowed
5556 -- to reference components in the current record).
5558 if Ekind
(E
) = E_Void
5560 (not Is_Record_Type
(Current_Scope
)
5561 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5563 Premature_Usage
(N
);
5565 -- If the entity is overloadable, collect all interpretations of the
5566 -- name for subsequent overload resolution. We optimize a bit here to
5567 -- do this only if we have an overloadable entity that is not on its
5568 -- own on the homonym chain.
5570 elsif Is_Overloadable
(E
)
5571 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5573 Collect_Interps
(N
);
5575 -- If no homonyms were visible, the entity is unambiguous
5577 if not Is_Overloaded
(N
) then
5578 if not Is_Actual_Parameter
then
5579 Generate_Reference
(E
, N
);
5583 -- Case of non-overloadable entity, set the entity providing that
5584 -- we do not have the case of a discriminant reference within a
5585 -- default expression. Such references are replaced with the
5586 -- corresponding discriminal, which is the formal corresponding to
5587 -- to the discriminant in the initialization procedure.
5590 -- Entity is unambiguous, indicate that it is referenced here
5592 -- For a renaming of an object, always generate simple reference,
5593 -- we don't try to keep track of assignments in this case, except
5594 -- in SPARK mode where renamings are traversed for generating
5595 -- local effects of subprograms.
5598 and then Present
(Renamed_Object
(E
))
5599 and then not GNATprove_Mode
5601 Generate_Reference
(E
, N
);
5603 -- If the renamed entity is a private protected component,
5604 -- reference the original component as well. This needs to be
5605 -- done because the private renamings are installed before any
5606 -- analysis has occurred. Reference to a private component will
5607 -- resolve to the renaming and the original component will be
5608 -- left unreferenced, hence the following.
5610 if Is_Prival
(E
) then
5611 Generate_Reference
(Prival_Link
(E
), N
);
5614 -- One odd case is that we do not want to set the Referenced flag
5615 -- if the entity is a label, and the identifier is the label in
5616 -- the source, since this is not a reference from the point of
5617 -- view of the user.
5619 elsif Nkind
(Parent
(N
)) = N_Label
then
5621 R
: constant Boolean := Referenced
(E
);
5624 -- Generate reference unless this is an actual parameter
5625 -- (see comment below)
5627 if Is_Actual_Parameter
then
5628 Generate_Reference
(E
, N
);
5629 Set_Referenced
(E
, R
);
5633 -- Normal case, not a label: generate reference
5636 if not Is_Actual_Parameter
then
5638 -- Package or generic package is always a simple reference
5640 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5641 Generate_Reference
(E
, N
, 'r');
5643 -- Else see if we have a left hand side
5648 Generate_Reference
(E
, N
, 'm');
5651 Generate_Reference
(E
, N
, 'r');
5653 -- If we don't know now, generate reference later
5656 Deferred_References
.Append
((E
, N
));
5661 Check_Nested_Access
(E
);
5664 Set_Entity_Or_Discriminal
(N
, E
);
5666 -- The name may designate a generalized reference, in which case
5667 -- the dereference interpretation will be included.
5669 if Ada_Version
>= Ada_2012
5671 (Nkind
(Parent
(N
)) in N_Subexpr
5672 or else Nkind_In
(Parent
(N
), N_Object_Declaration
,
5673 N_Assignment_Statement
))
5675 Check_Implicit_Dereference
(N
, Etype
(E
));
5680 -- Come here with entity set
5683 Check_Restriction_No_Use_Of_Entity
(N
);
5684 end Find_Direct_Name
;
5686 ------------------------
5687 -- Find_Expanded_Name --
5688 ------------------------
5690 -- This routine searches the homonym chain of the entity until it finds
5691 -- an entity declared in the scope denoted by the prefix. If the entity
5692 -- is private, it may nevertheless be immediately visible, if we are in
5693 -- the scope of its declaration.
5695 procedure Find_Expanded_Name
(N
: Node_Id
) is
5696 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean;
5697 -- Determine whether an arbitrary node N appears in pragmas [Refined_]
5698 -- Depends or [Refined_]Global.
5700 ----------------------------------
5701 -- In_Pragmas_Depends_Or_Global --
5702 ----------------------------------
5704 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean is
5708 -- Climb the parent chain looking for a pragma
5711 while Present
(Par
) loop
5712 if Nkind
(Par
) = N_Pragma
5713 and then Nam_In
(Pragma_Name
(Par
), Name_Depends
,
5715 Name_Refined_Depends
,
5716 Name_Refined_Global
)
5720 -- Prevent the search from going too far
5722 elsif Is_Body_Or_Package_Declaration
(Par
) then
5726 Par
:= Parent
(Par
);
5730 end In_Pragmas_Depends_Or_Global
;
5734 Selector
: constant Node_Id
:= Selector_Name
(N
);
5735 Candidate
: Entity_Id
:= Empty
;
5739 -- Start of processing for Find_Expanded_Name
5742 P_Name
:= Entity
(Prefix
(N
));
5744 -- If the prefix is a renamed package, look for the entity in the
5745 -- original package.
5747 if Ekind
(P_Name
) = E_Package
5748 and then Present
(Renamed_Object
(P_Name
))
5750 P_Name
:= Renamed_Object
(P_Name
);
5752 -- Rewrite node with entity field pointing to renamed object
5754 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5755 Set_Entity
(Prefix
(N
), P_Name
);
5757 -- If the prefix is an object of a concurrent type, look for
5758 -- the entity in the associated task or protected type.
5760 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5761 P_Name
:= Etype
(P_Name
);
5764 Id
:= Current_Entity
(Selector
);
5767 Is_New_Candidate
: Boolean;
5770 while Present
(Id
) loop
5771 if Scope
(Id
) = P_Name
then
5773 Is_New_Candidate
:= True;
5775 -- Handle abstract views of states and variables. These are
5776 -- acceptable only when the reference to the view appears in
5777 -- pragmas [Refined_]Depends and [Refined_]Global.
5779 if Ekind
(Id
) = E_Abstract_State
5780 and then From_Limited_With
(Id
)
5781 and then Present
(Non_Limited_View
(Id
))
5783 if In_Pragmas_Depends_Or_Global
(N
) then
5784 Candidate
:= Non_Limited_View
(Id
);
5785 Is_New_Candidate
:= True;
5787 -- Hide candidate because it is not used in a proper context
5791 Is_New_Candidate
:= False;
5795 -- Ada 2005 (AI-217): Handle shadow entities associated with
5796 -- types declared in limited-withed nested packages. We don't need
5797 -- to handle E_Incomplete_Subtype entities because the entities
5798 -- in the limited view are always E_Incomplete_Type and
5799 -- E_Class_Wide_Type entities (see Build_Limited_Views).
5801 -- Regarding the expression used to evaluate the scope, it
5802 -- is important to note that the limited view also has shadow
5803 -- entities associated nested packages. For this reason the
5804 -- correct scope of the entity is the scope of the real entity.
5805 -- The non-limited view may itself be incomplete, in which case
5806 -- get the full view if available.
5808 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
5809 and then From_Limited_With
(Id
)
5810 and then Present
(Non_Limited_View
(Id
))
5811 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5813 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5814 Is_New_Candidate
:= True;
5817 Is_New_Candidate
:= False;
5820 if Is_New_Candidate
then
5822 -- If entity is a child unit, either it is a visible child of
5823 -- the prefix, or we are in the body of a generic prefix, as
5824 -- will happen when a child unit is instantiated in the body
5825 -- of a generic parent. This is because the instance body does
5826 -- not restore the full compilation context, given that all
5827 -- non-local references have been captured.
5829 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5830 exit when Is_Visible_Lib_Unit
(Id
)
5831 or else (Is_Child_Unit
(Id
)
5832 and then In_Open_Scopes
(Scope
(Id
))
5833 and then In_Instance_Body
);
5835 exit when not Is_Hidden
(Id
);
5838 exit when Is_Immediately_Visible
(Id
);
5846 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5847 and then Is_Generic_Instance
(P_Name
)
5849 -- Expanded name denotes entity in (instance of) generic subprogram.
5850 -- The entity may be in the subprogram instance, or may denote one of
5851 -- the formals, which is declared in the enclosing wrapper package.
5853 P_Name
:= Scope
(P_Name
);
5855 Id
:= Current_Entity
(Selector
);
5856 while Present
(Id
) loop
5857 exit when Scope
(Id
) = P_Name
;
5862 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5863 Set_Etype
(N
, Any_Type
);
5865 -- If we are looking for an entity defined in System, try to find it
5866 -- in the child package that may have been provided as an extension
5867 -- to System. The Extend_System pragma will have supplied the name of
5868 -- the extension, which may have to be loaded.
5870 if Chars
(P_Name
) = Name_System
5871 and then Scope
(P_Name
) = Standard_Standard
5872 and then Present
(System_Extend_Unit
)
5873 and then Present_System_Aux
(N
)
5875 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5876 Find_Expanded_Name
(N
);
5879 elsif Nkind
(Selector
) = N_Operator_Symbol
5880 and then Has_Implicit_Operator
(N
)
5882 -- There is an implicit instance of the predefined operator in
5883 -- the given scope. The operator entity is defined in Standard.
5884 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5888 elsif Nkind
(Selector
) = N_Character_Literal
5889 and then Has_Implicit_Character_Literal
(N
)
5891 -- If there is no literal defined in the scope denoted by the
5892 -- prefix, the literal may belong to (a type derived from)
5893 -- Standard_Character, for which we have no explicit literals.
5898 -- If the prefix is a single concurrent object, use its name in
5899 -- the error message, rather than that of the anonymous type.
5901 if Is_Concurrent_Type
(P_Name
)
5902 and then Is_Internal_Name
(Chars
(P_Name
))
5904 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5906 Error_Msg_Node_2
:= P_Name
;
5909 if P_Name
= System_Aux_Id
then
5910 P_Name
:= Scope
(P_Name
);
5911 Set_Entity
(Prefix
(N
), P_Name
);
5914 if Present
(Candidate
) then
5916 -- If we know that the unit is a child unit we can give a more
5917 -- accurate error message.
5919 if Is_Child_Unit
(Candidate
) then
5921 -- If the candidate is a private child unit and we are in
5922 -- the visible part of a public unit, specialize the error
5923 -- message. There might be a private with_clause for it,
5924 -- but it is not currently active.
5926 if Is_Private_Descendant
(Candidate
)
5927 and then Ekind
(Current_Scope
) = E_Package
5928 and then not In_Private_Part
(Current_Scope
)
5929 and then not Is_Private_Descendant
(Current_Scope
)
5931 Error_Msg_N
("private child unit& is not visible here",
5934 -- Normal case where we have a missing with for a child unit
5937 Error_Msg_Qual_Level
:= 99;
5938 Error_Msg_NE
-- CODEFIX
5939 ("missing `WITH &;`", Selector
, Candidate
);
5940 Error_Msg_Qual_Level
:= 0;
5943 -- Here we don't know that this is a child unit
5946 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5950 -- Within the instantiation of a child unit, the prefix may
5951 -- denote the parent instance, but the selector has the name
5952 -- of the original child. That is to say, when A.B appears
5953 -- within an instantiation of generic child unit B, the scope
5954 -- stack includes an instance of A (P_Name) and an instance
5955 -- of B under some other name. We scan the scope to find this
5956 -- child instance, which is the desired entity.
5957 -- Note that the parent may itself be a child instance, if
5958 -- the reference is of the form A.B.C, in which case A.B has
5959 -- already been rewritten with the proper entity.
5961 if In_Open_Scopes
(P_Name
)
5962 and then Is_Generic_Instance
(P_Name
)
5965 Gen_Par
: constant Entity_Id
:=
5966 Generic_Parent
(Specification
5967 (Unit_Declaration_Node
(P_Name
)));
5968 S
: Entity_Id
:= Current_Scope
;
5972 for J
in reverse 0 .. Scope_Stack
.Last
loop
5973 S
:= Scope_Stack
.Table
(J
).Entity
;
5975 exit when S
= Standard_Standard
;
5977 if Ekind_In
(S
, E_Function
,
5981 P
:= Generic_Parent
(Specification
5982 (Unit_Declaration_Node
(S
)));
5984 -- Check that P is a generic child of the generic
5985 -- parent of the prefix.
5988 and then Chars
(P
) = Chars
(Selector
)
5989 and then Scope
(P
) = Gen_Par
6000 -- If this is a selection from Ada, System or Interfaces, then
6001 -- we assume a missing with for the corresponding package.
6003 if Is_Known_Unit
(N
) then
6004 if not Error_Posted
(N
) then
6005 Error_Msg_Node_2
:= Selector
;
6006 Error_Msg_N
-- CODEFIX
6007 ("missing `WITH &.&;`", Prefix
(N
));
6010 -- If this is a selection from a dummy package, then suppress
6011 -- the error message, of course the entity is missing if the
6012 -- package is missing.
6014 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
6017 -- Here we have the case of an undefined component
6021 -- The prefix may hide a homonym in the context that
6022 -- declares the desired entity. This error can use a
6023 -- specialized message.
6025 if In_Open_Scopes
(P_Name
) then
6027 H
: constant Entity_Id
:= Homonym
(P_Name
);
6031 and then Is_Compilation_Unit
(H
)
6033 (Is_Immediately_Visible
(H
)
6034 or else Is_Visible_Lib_Unit
(H
))
6036 Id
:= First_Entity
(H
);
6037 while Present
(Id
) loop
6038 if Chars
(Id
) = Chars
(Selector
) then
6039 Error_Msg_Qual_Level
:= 99;
6040 Error_Msg_Name_1
:= Chars
(Selector
);
6042 ("% not declared in&", N
, P_Name
);
6044 ("\use fully qualified name starting with "
6045 & "Standard to make& visible", N
, H
);
6046 Error_Msg_Qual_Level
:= 0;
6054 -- If not found, standard error message
6056 Error_Msg_NE
("& not declared in&", N
, Selector
);
6062 Error_Msg_NE
("& not declared in&", N
, Selector
);
6065 -- Check for misspelling of some entity in prefix
6067 Id
:= First_Entity
(P_Name
);
6068 while Present
(Id
) loop
6069 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6070 and then not Is_Internal_Name
(Chars
(Id
))
6072 Error_Msg_NE
-- CODEFIX
6073 ("possible misspelling of&", Selector
, Id
);
6080 -- Specialize the message if this may be an instantiation
6081 -- of a child unit that was not mentioned in the context.
6083 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6084 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6085 and then Is_Compilation_Unit
6086 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6088 Error_Msg_Node_2
:= Selector
;
6089 Error_Msg_N
-- CODEFIX
6090 ("\missing `WITH &.&;`", Prefix
(N
));
6100 if Comes_From_Source
(N
)
6101 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6102 and then Ekind
(Id
) = E_Access_Subprogram_Type
6103 and then Present
(Equivalent_Type
(Id
))
6105 -- If we are not actually generating distribution code (i.e. the
6106 -- current PCS is the dummy non-distributed version), then the
6107 -- Equivalent_Type will be missing, and Id should be treated as
6108 -- a regular access-to-subprogram type.
6110 Id
:= Equivalent_Type
(Id
);
6111 Set_Chars
(Selector
, Chars
(Id
));
6114 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6116 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6117 if From_Limited_With
(Id
)
6118 or else Is_Type
(Id
)
6119 or else Ekind
(Id
) = E_Package
6124 ("limited withed package can only be used to access "
6125 & "incomplete types", N
);
6129 if Is_Task_Type
(P_Name
)
6130 and then ((Ekind
(Id
) = E_Entry
6131 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6133 (Ekind
(Id
) = E_Entry_Family
6135 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6137 -- If both the task type and the entry are in scope, this may still
6138 -- be the expanded name of an entry formal.
6140 if In_Open_Scopes
(Id
)
6141 and then Nkind
(Parent
(N
)) = N_Selected_Component
6146 -- It is an entry call after all, either to the current task
6147 -- (which will deadlock) or to an enclosing task.
6149 Analyze_Selected_Component
(N
);
6154 Change_Selected_Component_To_Expanded_Name
(N
);
6156 -- Set appropriate type
6158 if Is_Type
(Id
) then
6161 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6164 -- Do style check and generate reference, but skip both steps if this
6165 -- entity has homonyms, since we may not have the right homonym set yet.
6166 -- The proper homonym will be set during the resolve phase.
6168 if Has_Homonym
(Id
) then
6172 Set_Entity_Or_Discriminal
(N
, Id
);
6176 Generate_Reference
(Id
, N
, 'm');
6178 Generate_Reference
(Id
, N
, 'r');
6180 Deferred_References
.Append
((Id
, N
));
6184 -- Check for violation of No_Wide_Characters
6186 Check_Wide_Character_Restriction
(Id
, N
);
6188 -- If the Ekind of the entity is Void, it means that all homonyms are
6189 -- hidden from all visibility (RM 8.3(5,14-20)).
6191 if Ekind
(Id
) = E_Void
then
6192 Premature_Usage
(N
);
6194 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6196 H
: Entity_Id
:= Homonym
(Id
);
6199 while Present
(H
) loop
6200 if Scope
(H
) = Scope
(Id
)
6201 and then (not Is_Hidden
(H
)
6202 or else Is_Immediately_Visible
(H
))
6204 Collect_Interps
(N
);
6211 -- If an extension of System is present, collect possible explicit
6212 -- overloadings declared in the extension.
6214 if Chars
(P_Name
) = Name_System
6215 and then Scope
(P_Name
) = Standard_Standard
6216 and then Present
(System_Extend_Unit
)
6217 and then Present_System_Aux
(N
)
6219 H
:= Current_Entity
(Id
);
6221 while Present
(H
) loop
6222 if Scope
(H
) = System_Aux_Id
then
6223 Add_One_Interp
(N
, H
, Etype
(H
));
6232 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6233 and then Scope
(Id
) /= Standard_Standard
6235 -- In addition to user-defined operators in the given scope, there
6236 -- may be an implicit instance of the predefined operator. The
6237 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6238 -- and added to the interpretations. Procedure Add_One_Interp will
6239 -- determine which hides which.
6241 if Has_Implicit_Operator
(N
) then
6246 -- If there is a single interpretation for N we can generate a
6247 -- reference to the unique entity found.
6249 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6250 Generate_Reference
(Id
, N
);
6252 end Find_Expanded_Name
;
6254 -------------------------
6255 -- Find_Renamed_Entity --
6256 -------------------------
6258 function Find_Renamed_Entity
6262 Is_Actual
: Boolean := False) return Entity_Id
6265 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6271 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6272 -- If the renamed entity is an implicit operator, check whether it is
6273 -- visible because its operand type is properly visible. This check
6274 -- applies to explicit renamed entities that appear in the source in a
6275 -- renaming declaration or a formal subprogram instance, but not to
6276 -- default generic actuals with a name.
6278 function Report_Overload
return Entity_Id
;
6279 -- List possible interpretations, and specialize message in the
6280 -- case of a generic actual.
6282 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6283 -- Determine whether a candidate subprogram is defined within the
6284 -- enclosing instance. If yes, it has precedence over outer candidates.
6286 --------------------------
6287 -- Is_Visible_Operation --
6288 --------------------------
6290 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6296 if Ekind
(Op
) /= E_Operator
6297 or else Scope
(Op
) /= Standard_Standard
6298 or else (In_Instance
6299 and then (not Is_Actual
6300 or else Present
(Enclosing_Instance
)))
6305 -- For a fixed point type operator, check the resulting type,
6306 -- because it may be a mixed mode integer * fixed operation.
6308 if Present
(Next_Formal
(First_Formal
(New_S
)))
6309 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6311 Typ
:= Etype
(New_S
);
6313 Typ
:= Etype
(First_Formal
(New_S
));
6316 Btyp
:= Base_Type
(Typ
);
6318 if Nkind
(Nam
) /= N_Expanded_Name
then
6319 return (In_Open_Scopes
(Scope
(Btyp
))
6320 or else Is_Potentially_Use_Visible
(Btyp
)
6321 or else In_Use
(Btyp
)
6322 or else In_Use
(Scope
(Btyp
)));
6325 Scop
:= Entity
(Prefix
(Nam
));
6327 if Ekind
(Scop
) = E_Package
6328 and then Present
(Renamed_Object
(Scop
))
6330 Scop
:= Renamed_Object
(Scop
);
6333 -- Operator is visible if prefix of expanded name denotes
6334 -- scope of type, or else type is defined in System_Aux
6335 -- and the prefix denotes System.
6337 return Scope
(Btyp
) = Scop
6338 or else (Scope
(Btyp
) = System_Aux_Id
6339 and then Scope
(Scope
(Btyp
)) = Scop
);
6342 end Is_Visible_Operation
;
6348 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6352 Sc
:= Scope
(Inner
);
6353 while Sc
/= Standard_Standard
loop
6364 ---------------------
6365 -- Report_Overload --
6366 ---------------------
6368 function Report_Overload
return Entity_Id
is
6371 Error_Msg_NE
-- CODEFIX
6372 ("ambiguous actual subprogram&, " &
6373 "possible interpretations:", N
, Nam
);
6375 Error_Msg_N
-- CODEFIX
6376 ("ambiguous subprogram, " &
6377 "possible interpretations:", N
);
6380 List_Interps
(Nam
, N
);
6382 end Report_Overload
;
6384 -- Start of processing for Find_Renamed_Entity
6388 Candidate_Renaming
:= Empty
;
6390 if Is_Overloaded
(Nam
) then
6391 Get_First_Interp
(Nam
, Ind
, It
);
6392 while Present
(It
.Nam
) loop
6393 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6394 and then Is_Visible_Operation
(It
.Nam
)
6396 if Old_S
/= Any_Id
then
6398 -- Note: The call to Disambiguate only happens if a
6399 -- previous interpretation was found, in which case I1
6400 -- has received a value.
6402 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6404 if It1
= No_Interp
then
6405 Inst
:= Enclosing_Instance
;
6407 if Present
(Inst
) then
6408 if Within
(It
.Nam
, Inst
) then
6409 if Within
(Old_S
, Inst
) then
6411 -- Choose the innermost subprogram, which would
6412 -- have hidden the outer one in the generic.
6414 if Scope_Depth
(It
.Nam
) <
6423 elsif Within
(Old_S
, Inst
) then
6427 return Report_Overload
;
6430 -- If not within an instance, ambiguity is real
6433 return Report_Overload
;
6447 Present
(First_Formal
(It
.Nam
))
6448 and then Present
(First_Formal
(New_S
))
6449 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6450 Base_Type
(Etype
(First_Formal
(New_S
))))
6452 Candidate_Renaming
:= It
.Nam
;
6455 Get_Next_Interp
(Ind
, It
);
6458 Set_Entity
(Nam
, Old_S
);
6460 if Old_S
/= Any_Id
then
6461 Set_Is_Overloaded
(Nam
, False);
6464 -- Non-overloaded case
6467 if Is_Actual
and then Present
(Enclosing_Instance
) then
6468 Old_S
:= Entity
(Nam
);
6470 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6471 Candidate_Renaming
:= New_S
;
6473 if Is_Visible_Operation
(Entity
(Nam
)) then
6474 Old_S
:= Entity
(Nam
);
6477 elsif Present
(First_Formal
(Entity
(Nam
)))
6478 and then Present
(First_Formal
(New_S
))
6479 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6480 Base_Type
(Etype
(First_Formal
(New_S
))))
6482 Candidate_Renaming
:= Entity
(Nam
);
6487 end Find_Renamed_Entity
;
6489 -----------------------------
6490 -- Find_Selected_Component --
6491 -----------------------------
6493 procedure Find_Selected_Component
(N
: Node_Id
) is
6494 P
: constant Node_Id
:= Prefix
(N
);
6497 -- Entity denoted by prefix
6504 function Available_Subtype
return Boolean;
6505 -- A small optimization: if the prefix is constrained and the component
6506 -- is an array type we may already have a usable subtype for it, so we
6507 -- can use it rather than generating a new one, because the bounds
6508 -- will be the values of the discriminants and not discriminant refs.
6509 -- This simplifies value tracing in GNATProve. For consistency, both
6510 -- the entity name and the subtype come from the constrained component.
6512 function Is_Reference_In_Subunit
return Boolean;
6513 -- In a subunit, the scope depth is not a proper measure of hiding,
6514 -- because the context of the proper body may itself hide entities in
6515 -- parent units. This rare case requires inspecting the tree directly
6516 -- because the proper body is inserted in the main unit and its context
6517 -- is simply added to that of the parent.
6519 -----------------------
6520 -- Available_Subtype --
6521 -----------------------
6523 function Available_Subtype
return Boolean is
6527 Comp
:= First_Entity
(Etype
(P
));
6528 while Present
(Comp
) loop
6529 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6530 Set_Etype
(N
, Etype
(Comp
));
6531 Set_Entity
(Selector_Name
(N
), Comp
);
6532 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6536 Next_Component
(Comp
);
6540 end Available_Subtype
;
6542 -----------------------------
6543 -- Is_Reference_In_Subunit --
6544 -----------------------------
6546 function Is_Reference_In_Subunit
return Boolean is
6548 Comp_Unit
: Node_Id
;
6552 while Present
(Comp_Unit
)
6553 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6555 Comp_Unit
:= Parent
(Comp_Unit
);
6558 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6562 -- Now check whether the package is in the context of the subunit
6564 Clause
:= First
(Context_Items
(Comp_Unit
));
6565 while Present
(Clause
) loop
6566 if Nkind
(Clause
) = N_With_Clause
6567 and then Entity
(Name
(Clause
)) = P_Name
6572 Clause
:= Next
(Clause
);
6576 end Is_Reference_In_Subunit
;
6578 -- Start of processing for Find_Selected_Component
6583 if Nkind
(P
) = N_Error
then
6587 -- Selector name cannot be a character literal or an operator symbol in
6588 -- SPARK, except for the operator symbol in a renaming.
6590 if Restriction_Check_Required
(SPARK_05
) then
6591 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6592 Check_SPARK_05_Restriction
6593 ("character literal cannot be prefixed", N
);
6594 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6595 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6597 Check_SPARK_05_Restriction
6598 ("operator symbol cannot be prefixed", N
);
6602 -- If the selector already has an entity, the node has been constructed
6603 -- in the course of expansion, and is known to be valid. Do not verify
6604 -- that it is defined for the type (it may be a private component used
6605 -- in the expansion of record equality).
6607 if Present
(Entity
(Selector_Name
(N
))) then
6608 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6610 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6611 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6615 Set_Etype
(Sel_Name
, Etype
(Selector
));
6617 if not Is_Entity_Name
(P
) then
6621 -- Build an actual subtype except for the first parameter
6622 -- of an init proc, where this actual subtype is by
6623 -- definition incorrect, since the object is uninitialized
6624 -- (and does not even have defined discriminants etc.)
6626 if Is_Entity_Name
(P
)
6627 and then Ekind
(Entity
(P
)) = E_Function
6629 Nam
:= New_Copy
(P
);
6631 if Is_Overloaded
(P
) then
6632 Save_Interps
(P
, Nam
);
6635 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6637 Analyze_Selected_Component
(N
);
6640 elsif Ekind
(Selector
) = E_Component
6641 and then (not Is_Entity_Name
(P
)
6642 or else Chars
(Entity
(P
)) /= Name_uInit
)
6644 -- Check if we already have an available subtype we can use
6646 if Ekind
(Etype
(P
)) = E_Record_Subtype
6647 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6648 and then Is_Array_Type
(Etype
(Selector
))
6649 and then not Is_Packed
(Etype
(Selector
))
6650 and then Available_Subtype
6654 -- Do not build the subtype when referencing components of
6655 -- dispatch table wrappers. Required to avoid generating
6656 -- elaboration code with HI runtimes. JVM and .NET use a
6657 -- modified version of Ada.Tags which does not contain RE_
6658 -- Dispatch_Table_Wrapper and RE_No_Dispatch_Table_Wrapper.
6659 -- Avoid raising RE_Not_Available exception in those cases.
6661 elsif VM_Target
= No_VM
6662 and then RTU_Loaded
(Ada_Tags
)
6664 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6665 and then Scope
(Selector
) =
6666 RTE
(RE_Dispatch_Table_Wrapper
))
6668 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6669 and then Scope
(Selector
) =
6670 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6675 Build_Actual_Subtype_Of_Component
6676 (Etype
(Selector
), N
);
6683 if No
(C_Etype
) then
6684 C_Etype
:= Etype
(Selector
);
6686 Insert_Action
(N
, C_Etype
);
6687 C_Etype
:= Defining_Identifier
(C_Etype
);
6690 Set_Etype
(N
, C_Etype
);
6693 -- If this is the name of an entry or protected operation, and
6694 -- the prefix is an access type, insert an explicit dereference,
6695 -- so that entry calls are treated uniformly.
6697 if Is_Access_Type
(Etype
(P
))
6698 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6701 New_P
: constant Node_Id
:=
6702 Make_Explicit_Dereference
(Sloc
(P
),
6703 Prefix
=> Relocate_Node
(P
));
6706 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6710 -- If the selected component appears within a default expression
6711 -- and it has an actual subtype, the pre-analysis has not yet
6712 -- completed its analysis, because Insert_Actions is disabled in
6713 -- that context. Within the init proc of the enclosing type we
6714 -- must complete this analysis, if an actual subtype was created.
6716 elsif Inside_Init_Proc
then
6718 Typ
: constant Entity_Id
:= Etype
(N
);
6719 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6721 if Nkind
(Decl
) = N_Subtype_Declaration
6722 and then not Analyzed
(Decl
)
6723 and then Is_List_Member
(Decl
)
6724 and then No
(Parent
(Decl
))
6727 Insert_Action
(N
, Decl
);
6734 elsif Is_Entity_Name
(P
) then
6735 P_Name
:= Entity
(P
);
6737 -- The prefix may denote an enclosing type which is the completion
6738 -- of an incomplete type declaration.
6740 if Is_Type
(P_Name
) then
6741 Set_Entity
(P
, Get_Full_View
(P_Name
));
6742 Set_Etype
(P
, Entity
(P
));
6743 P_Name
:= Entity
(P
);
6746 P_Type
:= Base_Type
(Etype
(P
));
6748 if Debug_Flag_E
then
6749 Write_Str
("Found prefix type to be ");
6750 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6753 -- The designated type may be a limited view with no components.
6754 -- Check whether the non-limited view is available, because in some
6755 -- cases this will not be set when installing the context.
6757 if Is_Access_Type
(P_Type
) then
6759 D
: constant Entity_Id
:= Directly_Designated_Type
(P_Type
);
6761 if Is_Incomplete_Type
(D
)
6762 and then From_Limited_With
(D
)
6763 and then Present
(Non_Limited_View
(D
))
6765 Set_Directly_Designated_Type
(P_Type
, Non_Limited_View
(D
));
6770 -- First check for components of a record object (not the
6771 -- result of a call, which is handled below).
6773 if Is_Appropriate_For_Record
(P_Type
)
6774 and then not Is_Overloadable
(P_Name
)
6775 and then not Is_Type
(P_Name
)
6777 -- Selected component of record. Type checking will validate
6778 -- name of selector.
6780 -- ??? Could we rewrite an implicit dereference into an explicit
6783 Analyze_Selected_Component
(N
);
6785 -- Reference to type name in predicate/invariant expression
6787 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6788 and then not In_Open_Scopes
(P_Name
)
6789 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6790 or else not In_Open_Scopes
(Etype
(P_Name
)))
6792 -- Call to protected operation or entry. Type checking is
6793 -- needed on the prefix.
6795 Analyze_Selected_Component
(N
);
6797 elsif (In_Open_Scopes
(P_Name
)
6798 and then Ekind
(P_Name
) /= E_Void
6799 and then not Is_Overloadable
(P_Name
))
6800 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6801 and then In_Open_Scopes
(Etype
(P_Name
)))
6803 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6804 -- enclosing construct that is not a subprogram or accept.
6806 Find_Expanded_Name
(N
);
6808 elsif Ekind
(P_Name
) = E_Package
then
6809 Find_Expanded_Name
(N
);
6811 elsif Is_Overloadable
(P_Name
) then
6813 -- The subprogram may be a renaming (of an enclosing scope) as
6814 -- in the case of the name of the generic within an instantiation.
6816 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6817 and then Present
(Alias
(P_Name
))
6818 and then Is_Generic_Instance
(Alias
(P_Name
))
6820 P_Name
:= Alias
(P_Name
);
6823 if Is_Overloaded
(P
) then
6825 -- The prefix must resolve to a unique enclosing construct
6828 Found
: Boolean := False;
6833 Get_First_Interp
(P
, Ind
, It
);
6834 while Present
(It
.Nam
) loop
6835 if In_Open_Scopes
(It
.Nam
) then
6838 "prefix must be unique enclosing scope", N
);
6839 Set_Entity
(N
, Any_Id
);
6840 Set_Etype
(N
, Any_Type
);
6849 Get_Next_Interp
(Ind
, It
);
6854 if In_Open_Scopes
(P_Name
) then
6855 Set_Entity
(P
, P_Name
);
6856 Set_Is_Overloaded
(P
, False);
6857 Find_Expanded_Name
(N
);
6860 -- If no interpretation as an expanded name is possible, it
6861 -- must be a selected component of a record returned by a
6862 -- function call. Reformat prefix as a function call, the rest
6863 -- is done by type resolution.
6865 -- Error if the prefix is procedure or entry, as is P.X
6867 if Ekind
(P_Name
) /= E_Function
6869 (not Is_Overloaded
(P
)
6870 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6872 -- Prefix may mention a package that is hidden by a local
6873 -- declaration: let the user know. Scan the full homonym
6874 -- chain, the candidate package may be anywhere on it.
6876 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6877 P_Name
:= Current_Entity
(P_Name
);
6879 while Present
(P_Name
) loop
6880 exit when Ekind
(P_Name
) = E_Package
;
6881 P_Name
:= Homonym
(P_Name
);
6884 if Present
(P_Name
) then
6885 if not Is_Reference_In_Subunit
then
6886 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6888 ("package& is hidden by declaration#", N
, P_Name
);
6891 Set_Entity
(Prefix
(N
), P_Name
);
6892 Find_Expanded_Name
(N
);
6896 P_Name
:= Entity
(Prefix
(N
));
6901 ("invalid prefix in selected component&", N
, P_Name
);
6902 Change_Selected_Component_To_Expanded_Name
(N
);
6903 Set_Entity
(N
, Any_Id
);
6904 Set_Etype
(N
, Any_Type
);
6906 -- Here we have a function call, so do the reformatting
6909 Nam
:= New_Copy
(P
);
6910 Save_Interps
(P
, Nam
);
6912 -- We use Replace here because this is one of those cases
6913 -- where the parser has missclassified the node, and we
6914 -- fix things up and then do the semantic analysis on the
6915 -- fixed up node. Normally we do this using one of the
6916 -- Sinfo.CN routines, but this is too tricky for that.
6918 -- Note that using Rewrite would be wrong, because we
6919 -- would have a tree where the original node is unanalyzed,
6920 -- and this violates the required interface for ASIS.
6923 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6925 -- Now analyze the reformatted node
6928 Analyze_Selected_Component
(N
);
6932 -- Remaining cases generate various error messages
6935 -- Format node as expanded name, to avoid cascaded errors
6937 Change_Selected_Component_To_Expanded_Name
(N
);
6938 Set_Entity
(N
, Any_Id
);
6939 Set_Etype
(N
, Any_Type
);
6941 -- Issue error message, but avoid this if error issued already.
6942 -- Use identifier of prefix if one is available.
6944 if P_Name
= Any_Id
then
6947 elsif Ekind
(P_Name
) = E_Void
then
6948 Premature_Usage
(P
);
6950 elsif Nkind
(P
) /= N_Attribute_Reference
then
6952 -- This may have been meant as a prefixed call to a primitive
6953 -- of an untagged type.
6956 F
: constant Entity_Id
:=
6957 Current_Entity
(Selector_Name
(N
));
6960 and then Is_Overloadable
(F
)
6961 and then Present
(First_Entity
(F
))
6962 and then Etype
(First_Entity
(F
)) = Etype
(P
)
6963 and then not Is_Tagged_Type
(Etype
(P
))
6966 ("prefixed call is only allowed for objects "
6967 & "of a tagged type", N
);
6971 Error_Msg_N
("invalid prefix in selected component&", P
);
6973 if Is_Access_Type
(P_Type
)
6974 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
6977 ("\dereference must not be of an incomplete type "
6978 & "(RM 3.10.1)", P
);
6982 Error_Msg_N
("invalid prefix in selected component", P
);
6986 -- Selector name is restricted in SPARK
6988 if Nkind
(N
) = N_Expanded_Name
6989 and then Restriction_Check_Required
(SPARK_05
)
6991 if Is_Subprogram
(P_Name
) then
6992 Check_SPARK_05_Restriction
6993 ("prefix of expanded name cannot be a subprogram", P
);
6994 elsif Ekind
(P_Name
) = E_Loop
then
6995 Check_SPARK_05_Restriction
6996 ("prefix of expanded name cannot be a loop statement", P
);
7001 -- If prefix is not the name of an entity, it must be an expression,
7002 -- whose type is appropriate for a record. This is determined by
7005 Analyze_Selected_Component
(N
);
7008 Analyze_Dimension
(N
);
7009 end Find_Selected_Component
;
7015 procedure Find_Type
(N
: Node_Id
) is
7025 elsif Nkind
(N
) = N_Attribute_Reference
then
7027 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7028 -- need to enforce that at this point, since the declaration of the
7029 -- tagged type in the prefix would have been flagged already.
7031 if Attribute_Name
(N
) = Name_Class
then
7032 Check_Restriction
(No_Dispatch
, N
);
7033 Find_Type
(Prefix
(N
));
7035 -- Propagate error from bad prefix
7037 if Etype
(Prefix
(N
)) = Any_Type
then
7038 Set_Entity
(N
, Any_Type
);
7039 Set_Etype
(N
, Any_Type
);
7043 T
:= Base_Type
(Entity
(Prefix
(N
)));
7045 -- Case where type is not known to be tagged. Its appearance in
7046 -- the prefix of the 'Class attribute indicates that the full view
7049 if not Is_Tagged_Type
(T
) then
7050 if Ekind
(T
) = E_Incomplete_Type
then
7052 -- It is legal to denote the class type of an incomplete
7053 -- type. The full type will have to be tagged, of course.
7054 -- In Ada 2005 this usage is declared obsolescent, so we
7055 -- warn accordingly. This usage is only legal if the type
7056 -- is completed in the current scope, and not for a limited
7059 if Ada_Version
>= Ada_2005
then
7061 -- Test whether the Available_View of a limited type view
7062 -- is tagged, since the limited view may not be marked as
7063 -- tagged if the type itself has an untagged incomplete
7064 -- type view in its package.
7066 if From_Limited_With
(T
)
7067 and then not Is_Tagged_Type
(Available_View
(T
))
7070 ("prefix of Class attribute must be tagged", N
);
7071 Set_Etype
(N
, Any_Type
);
7072 Set_Entity
(N
, Any_Type
);
7075 -- ??? This test is temporarily disabled (always
7076 -- False) because it causes an unwanted warning on
7077 -- GNAT sources (built with -gnatg, which includes
7078 -- Warn_On_Obsolescent_ Feature). Once this issue
7079 -- is cleared in the sources, it can be enabled.
7081 elsif Warn_On_Obsolescent_Feature
and then False then
7083 ("applying 'Class to an untagged incomplete type"
7084 & " is an obsolescent feature (RM J.11)?r?", N
);
7088 Set_Is_Tagged_Type
(T
);
7089 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7090 Make_Class_Wide_Type
(T
);
7091 Set_Entity
(N
, Class_Wide_Type
(T
));
7092 Set_Etype
(N
, Class_Wide_Type
(T
));
7094 elsif Ekind
(T
) = E_Private_Type
7095 and then not Is_Generic_Type
(T
)
7096 and then In_Private_Part
(Scope
(T
))
7098 -- The Class attribute can be applied to an untagged private
7099 -- type fulfilled by a tagged type prior to the full type
7100 -- declaration (but only within the parent package's private
7101 -- part). Create the class-wide type now and check that the
7102 -- full type is tagged later during its analysis. Note that
7103 -- we do not mark the private type as tagged, unlike the
7104 -- case of incomplete types, because the type must still
7105 -- appear untagged to outside units.
7107 if No
(Class_Wide_Type
(T
)) then
7108 Make_Class_Wide_Type
(T
);
7111 Set_Entity
(N
, Class_Wide_Type
(T
));
7112 Set_Etype
(N
, Class_Wide_Type
(T
));
7115 -- Should we introduce a type Any_Tagged and use Wrong_Type
7116 -- here, it would be a bit more consistent???
7119 ("tagged type required, found}",
7120 Prefix
(N
), First_Subtype
(T
));
7121 Set_Entity
(N
, Any_Type
);
7125 -- Case of tagged type
7128 if Is_Concurrent_Type
(T
) then
7129 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7131 -- Previous error. Use current type, which at least
7132 -- provides some operations.
7134 C
:= Entity
(Prefix
(N
));
7137 C
:= Class_Wide_Type
7138 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7142 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7145 Set_Entity_With_Checks
(N
, C
);
7146 Generate_Reference
(C
, N
);
7150 -- Base attribute, not allowed in Ada 83
7152 elsif Attribute_Name
(N
) = Name_Base
then
7153 Error_Msg_Name_1
:= Name_Base
;
7154 Check_SPARK_05_Restriction
7155 ("attribute% is only allowed as prefix of another attribute", N
);
7157 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7159 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7162 Find_Type
(Prefix
(N
));
7163 Typ
:= Entity
(Prefix
(N
));
7165 if Ada_Version
>= Ada_95
7166 and then not Is_Scalar_Type
(Typ
)
7167 and then not Is_Generic_Type
(Typ
)
7170 ("prefix of Base attribute must be scalar type",
7173 elsif Warn_On_Redundant_Constructs
7174 and then Base_Type
(Typ
) = Typ
7176 Error_Msg_NE
-- CODEFIX
7177 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7180 T
:= Base_Type
(Typ
);
7182 -- Rewrite attribute reference with type itself (see similar
7183 -- processing in Analyze_Attribute, case Base). Preserve prefix
7184 -- if present, for other legality checks.
7186 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7188 Make_Expanded_Name
(Sloc
(N
),
7190 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7191 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7194 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7201 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7203 -- This is handled in Analyze_Attribute
7207 -- All other attributes are invalid in a subtype mark
7210 Error_Msg_N
("invalid attribute in subtype mark", N
);
7216 if Is_Entity_Name
(N
) then
7217 T_Name
:= Entity
(N
);
7219 Error_Msg_N
("subtype mark required in this context", N
);
7220 Set_Etype
(N
, Any_Type
);
7224 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7226 -- Undefined id. Make it into a valid type
7228 Set_Entity
(N
, Any_Type
);
7230 elsif not Is_Type
(T_Name
)
7231 and then T_Name
/= Standard_Void_Type
7233 Error_Msg_Sloc
:= Sloc
(T_Name
);
7234 Error_Msg_N
("subtype mark required in this context", N
);
7235 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7236 Set_Entity
(N
, Any_Type
);
7239 -- If the type is an incomplete type created to handle
7240 -- anonymous access components of a record type, then the
7241 -- incomplete type is the visible entity and subsequent
7242 -- references will point to it. Mark the original full
7243 -- type as referenced, to prevent spurious warnings.
7245 if Is_Incomplete_Type
(T_Name
)
7246 and then Present
(Full_View
(T_Name
))
7247 and then not Comes_From_Source
(T_Name
)
7249 Set_Referenced
(Full_View
(T_Name
));
7252 T_Name
:= Get_Full_View
(T_Name
);
7254 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7255 -- limited-with clauses
7257 if From_Limited_With
(T_Name
)
7258 and then Ekind
(T_Name
) in Incomplete_Kind
7259 and then Present
(Non_Limited_View
(T_Name
))
7260 and then Is_Interface
(Non_Limited_View
(T_Name
))
7262 T_Name
:= Non_Limited_View
(T_Name
);
7265 if In_Open_Scopes
(T_Name
) then
7266 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7268 -- In Ada 2005, a task name can be used in an access
7269 -- definition within its own body. It cannot be used
7270 -- in the discriminant part of the task declaration,
7271 -- nor anywhere else in the declaration because entries
7272 -- cannot have access parameters.
7274 if Ada_Version
>= Ada_2005
7275 and then Nkind
(Parent
(N
)) = N_Access_Definition
7277 Set_Entity
(N
, T_Name
);
7278 Set_Etype
(N
, T_Name
);
7280 if Has_Completion
(T_Name
) then
7285 ("task type cannot be used as type mark " &
7286 "within its own declaration", N
);
7291 ("task type cannot be used as type mark " &
7292 "within its own spec or body", N
);
7295 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7297 -- In Ada 2005, a protected name can be used in an access
7298 -- definition within its own body.
7300 if Ada_Version
>= Ada_2005
7301 and then Nkind
(Parent
(N
)) = N_Access_Definition
7303 Set_Entity
(N
, T_Name
);
7304 Set_Etype
(N
, T_Name
);
7309 ("protected type cannot be used as type mark " &
7310 "within its own spec or body", N
);
7314 Error_Msg_N
("type declaration cannot refer to itself", N
);
7317 Set_Etype
(N
, Any_Type
);
7318 Set_Entity
(N
, Any_Type
);
7319 Set_Error_Posted
(T_Name
);
7323 Set_Entity
(N
, T_Name
);
7324 Set_Etype
(N
, T_Name
);
7328 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7329 if Is_Fixed_Point_Type
(Etype
(N
)) then
7330 Check_Restriction
(No_Fixed_Point
, N
);
7331 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7332 Check_Restriction
(No_Floating_Point
, N
);
7335 -- A Ghost type must appear in a specific context
7337 if Is_Ghost_Entity
(Etype
(N
)) then
7338 Check_Ghost_Context
(Etype
(N
), N
);
7343 ------------------------------------
7344 -- Has_Implicit_Character_Literal --
7345 ------------------------------------
7347 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7349 Found
: Boolean := False;
7350 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7351 Priv_Id
: Entity_Id
:= Empty
;
7354 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7355 Priv_Id
:= First_Private_Entity
(P
);
7358 if P
= Standard_Standard
then
7359 Change_Selected_Component_To_Expanded_Name
(N
);
7360 Rewrite
(N
, Selector_Name
(N
));
7362 Set_Etype
(Original_Node
(N
), Standard_Character
);
7366 Id
:= First_Entity
(P
);
7367 while Present
(Id
) and then Id
/= Priv_Id
loop
7368 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7370 -- We replace the node with the literal itself, resolve as a
7371 -- character, and set the type correctly.
7374 Change_Selected_Component_To_Expanded_Name
(N
);
7375 Rewrite
(N
, Selector_Name
(N
));
7378 Set_Etype
(Original_Node
(N
), Id
);
7382 -- More than one type derived from Character in given scope.
7383 -- Collect all possible interpretations.
7385 Add_One_Interp
(N
, Id
, Id
);
7393 end Has_Implicit_Character_Literal
;
7395 ----------------------
7396 -- Has_Private_With --
7397 ----------------------
7399 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7400 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7404 Item
:= First
(Context_Items
(Comp_Unit
));
7405 while Present
(Item
) loop
7406 if Nkind
(Item
) = N_With_Clause
7407 and then Private_Present
(Item
)
7408 and then Entity
(Name
(Item
)) = E
7417 end Has_Private_With
;
7419 ---------------------------
7420 -- Has_Implicit_Operator --
7421 ---------------------------
7423 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7424 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7425 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7427 Priv_Id
: Entity_Id
:= Empty
;
7429 procedure Add_Implicit_Operator
7431 Op_Type
: Entity_Id
:= Empty
);
7432 -- Add implicit interpretation to node N, using the type for which a
7433 -- predefined operator exists. If the operator yields a boolean type,
7434 -- the Operand_Type is implicitly referenced by the operator, and a
7435 -- reference to it must be generated.
7437 ---------------------------
7438 -- Add_Implicit_Operator --
7439 ---------------------------
7441 procedure Add_Implicit_Operator
7443 Op_Type
: Entity_Id
:= Empty
)
7445 Predef_Op
: Entity_Id
;
7448 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7449 while Present
(Predef_Op
)
7450 and then Scope
(Predef_Op
) /= Standard_Standard
7452 Predef_Op
:= Homonym
(Predef_Op
);
7455 if Nkind
(N
) = N_Selected_Component
then
7456 Change_Selected_Component_To_Expanded_Name
(N
);
7459 -- If the context is an unanalyzed function call, determine whether
7460 -- a binary or unary interpretation is required.
7462 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7464 Is_Binary_Call
: constant Boolean :=
7466 (Next
(First
(Expressions
(Parent
(N
)))));
7467 Is_Binary_Op
: constant Boolean :=
7469 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7470 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7473 if Is_Binary_Call
then
7474 if Is_Binary_Op
then
7475 Add_One_Interp
(N
, Predef_Op
, T
);
7477 Add_One_Interp
(N
, Predef_Op2
, T
);
7481 if not Is_Binary_Op
then
7482 Add_One_Interp
(N
, Predef_Op
, T
);
7484 Add_One_Interp
(N
, Predef_Op2
, T
);
7490 Add_One_Interp
(N
, Predef_Op
, T
);
7492 -- For operators with unary and binary interpretations, if
7493 -- context is not a call, add both
7495 if Present
(Homonym
(Predef_Op
)) then
7496 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7500 -- The node is a reference to a predefined operator, and
7501 -- an implicit reference to the type of its operands.
7503 if Present
(Op_Type
) then
7504 Generate_Operator_Reference
(N
, Op_Type
);
7506 Generate_Operator_Reference
(N
, T
);
7508 end Add_Implicit_Operator
;
7510 -- Start of processing for Has_Implicit_Operator
7513 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7514 Priv_Id
:= First_Private_Entity
(P
);
7517 Id
:= First_Entity
(P
);
7521 -- Boolean operators: an implicit declaration exists if the scope
7522 -- contains a declaration for a derived Boolean type, or for an
7523 -- array of Boolean type.
7525 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7526 while Id
/= Priv_Id
loop
7527 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7528 Add_Implicit_Operator
(Id
);
7535 -- Equality: look for any non-limited type (result is Boolean)
7537 when Name_Op_Eq | Name_Op_Ne
=>
7538 while Id
/= Priv_Id
loop
7540 and then not Is_Limited_Type
(Id
)
7541 and then Is_Base_Type
(Id
)
7543 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7550 -- Comparison operators: scalar type, or array of scalar
7552 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7553 while Id
/= Priv_Id
loop
7554 if (Is_Scalar_Type
(Id
)
7555 or else (Is_Array_Type
(Id
)
7556 and then Is_Scalar_Type
(Component_Type
(Id
))))
7557 and then Is_Base_Type
(Id
)
7559 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7566 -- Arithmetic operators: any numeric type
7576 while Id
/= Priv_Id
loop
7577 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7578 Add_Implicit_Operator
(Id
);
7585 -- Concatenation: any one-dimensional array type
7587 when Name_Op_Concat
=>
7588 while Id
/= Priv_Id
loop
7589 if Is_Array_Type
(Id
)
7590 and then Number_Dimensions
(Id
) = 1
7591 and then Is_Base_Type
(Id
)
7593 Add_Implicit_Operator
(Id
);
7600 -- What is the others condition here? Should we be using a
7601 -- subtype of Name_Id that would restrict to operators ???
7603 when others => null;
7606 -- If we fall through, then we do not have an implicit operator
7610 end Has_Implicit_Operator
;
7612 -----------------------------------
7613 -- Has_Loop_In_Inner_Open_Scopes --
7614 -----------------------------------
7616 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7618 -- Several scope stacks are maintained by Scope_Stack. The base of the
7619 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7620 -- flag in the scope stack entry. Note that the scope stacks used to
7621 -- simply be delimited implicitly by the presence of Standard_Standard
7622 -- at their base, but there now are cases where this is not sufficient
7623 -- because Standard_Standard actually may appear in the middle of the
7624 -- active set of scopes.
7626 for J
in reverse 0 .. Scope_Stack
.Last
loop
7628 -- S was reached without seing a loop scope first
7630 if Scope_Stack
.Table
(J
).Entity
= S
then
7633 -- S was not yet reached, so it contains at least one inner loop
7635 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7639 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7640 -- cases where Standard_Standard appears in the middle of the active
7641 -- set of scopes. This affects the declaration and overriding of
7642 -- private inherited operations in instantiations of generic child
7645 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7648 raise Program_Error
; -- unreachable
7649 end Has_Loop_In_Inner_Open_Scopes
;
7651 --------------------
7652 -- In_Open_Scopes --
7653 --------------------
7655 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7657 -- Several scope stacks are maintained by Scope_Stack. The base of the
7658 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7659 -- flag in the scope stack entry. Note that the scope stacks used to
7660 -- simply be delimited implicitly by the presence of Standard_Standard
7661 -- at their base, but there now are cases where this is not sufficient
7662 -- because Standard_Standard actually may appear in the middle of the
7663 -- active set of scopes.
7665 for J
in reverse 0 .. Scope_Stack
.Last
loop
7666 if Scope_Stack
.Table
(J
).Entity
= S
then
7670 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7671 -- cases where Standard_Standard appears in the middle of the active
7672 -- set of scopes. This affects the declaration and overriding of
7673 -- private inherited operations in instantiations of generic child
7676 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7682 -----------------------------
7683 -- Inherit_Renamed_Profile --
7684 -----------------------------
7686 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7693 if Ekind
(Old_S
) = E_Operator
then
7694 New_F
:= First_Formal
(New_S
);
7696 while Present
(New_F
) loop
7697 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7698 Next_Formal
(New_F
);
7701 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7704 New_F
:= First_Formal
(New_S
);
7705 Old_F
:= First_Formal
(Old_S
);
7707 while Present
(New_F
) loop
7708 New_T
:= Etype
(New_F
);
7709 Old_T
:= Etype
(Old_F
);
7711 -- If the new type is a renaming of the old one, as is the
7712 -- case for actuals in instances, retain its name, to simplify
7713 -- later disambiguation.
7715 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7716 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7717 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7721 Set_Etype
(New_F
, Old_T
);
7724 Next_Formal
(New_F
);
7725 Next_Formal
(Old_F
);
7728 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7729 Set_Etype
(New_S
, Etype
(Old_S
));
7732 end Inherit_Renamed_Profile
;
7738 procedure Initialize
is
7743 -------------------------
7744 -- Install_Use_Clauses --
7745 -------------------------
7747 procedure Install_Use_Clauses
7749 Force_Installation
: Boolean := False)
7757 while Present
(U
) loop
7759 -- Case of USE package
7761 if Nkind
(U
) = N_Use_Package_Clause
then
7762 P
:= First
(Names
(U
));
7763 while Present
(P
) loop
7766 if Ekind
(Id
) = E_Package
then
7768 Note_Redundant_Use
(P
);
7770 elsif Present
(Renamed_Object
(Id
))
7771 and then In_Use
(Renamed_Object
(Id
))
7773 Note_Redundant_Use
(P
);
7775 elsif Force_Installation
or else Applicable_Use
(P
) then
7776 Use_One_Package
(Id
, U
);
7787 P
:= First
(Subtype_Marks
(U
));
7788 while Present
(P
) loop
7789 if not Is_Entity_Name
(P
)
7790 or else No
(Entity
(P
))
7794 elsif Entity
(P
) /= Any_Type
then
7802 Next_Use_Clause
(U
);
7804 end Install_Use_Clauses
;
7806 -------------------------------------
7807 -- Is_Appropriate_For_Entry_Prefix --
7808 -------------------------------------
7810 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7811 P_Type
: Entity_Id
:= T
;
7814 if Is_Access_Type
(P_Type
) then
7815 P_Type
:= Designated_Type
(P_Type
);
7818 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7819 end Is_Appropriate_For_Entry_Prefix
;
7821 -------------------------------
7822 -- Is_Appropriate_For_Record --
7823 -------------------------------
7825 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7827 function Has_Components
(T1
: Entity_Id
) return Boolean;
7828 -- Determine if given type has components (i.e. is either a record
7829 -- type or a type that has discriminants).
7831 --------------------
7832 -- Has_Components --
7833 --------------------
7835 function Has_Components
(T1
: Entity_Id
) return Boolean is
7837 return Is_Record_Type
(T1
)
7838 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7839 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7840 or else (Is_Incomplete_Type
(T1
)
7841 and then From_Limited_With
(T1
)
7842 and then Present
(Non_Limited_View
(T1
))
7843 and then Is_Record_Type
7844 (Get_Full_View
(Non_Limited_View
(T1
))));
7847 -- Start of processing for Is_Appropriate_For_Record
7852 and then (Has_Components
(T
)
7853 or else (Is_Access_Type
(T
)
7854 and then Has_Components
(Designated_Type
(T
))));
7855 end Is_Appropriate_For_Record
;
7857 ------------------------
7858 -- Note_Redundant_Use --
7859 ------------------------
7861 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7862 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7863 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7864 Decl
: constant Node_Id
:= Parent
(Clause
);
7866 Prev_Use
: Node_Id
:= Empty
;
7867 Redundant
: Node_Id
:= Empty
;
7868 -- The Use_Clause which is actually redundant. In the simplest case it
7869 -- is Pack itself, but when we compile a body we install its context
7870 -- before that of its spec, in which case it is the use_clause in the
7871 -- spec that will appear to be redundant, and we want the warning to be
7872 -- placed on the body. Similar complications appear when the redundancy
7873 -- is between a child unit and one of its ancestors.
7876 Set_Redundant_Use
(Clause
, True);
7878 if not Comes_From_Source
(Clause
)
7880 or else not Warn_On_Redundant_Constructs
7885 if not Is_Compilation_Unit
(Current_Scope
) then
7887 -- If the use_clause is in an inner scope, it is made redundant by
7888 -- some clause in the current context, with one exception: If we're
7889 -- compiling a nested package body, and the use_clause comes from the
7890 -- corresponding spec, the clause is not necessarily fully redundant,
7891 -- so we should not warn. If a warning was warranted, it would have
7892 -- been given when the spec was processed.
7894 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7896 Package_Spec_Entity
: constant Entity_Id
:=
7897 Defining_Unit_Name
(Parent
(Decl
));
7899 if In_Package_Body
(Package_Spec_Entity
) then
7905 Redundant
:= Clause
;
7906 Prev_Use
:= Cur_Use
;
7908 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7910 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7911 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7915 if Cur_Unit
= New_Unit
then
7917 -- Redundant clause in same body
7919 Redundant
:= Clause
;
7920 Prev_Use
:= Cur_Use
;
7922 elsif Cur_Unit
= Current_Sem_Unit
then
7924 -- If the new clause is not in the current unit it has been
7925 -- analyzed first, and it makes the other one redundant.
7926 -- However, if the new clause appears in a subunit, Cur_Unit
7927 -- is still the parent, and in that case the redundant one
7928 -- is the one appearing in the subunit.
7930 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7931 Redundant
:= Clause
;
7932 Prev_Use
:= Cur_Use
;
7934 -- Most common case: redundant clause in body,
7935 -- original clause in spec. Current scope is spec entity.
7940 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7942 Redundant
:= Cur_Use
;
7946 -- The new clause may appear in an unrelated unit, when
7947 -- the parents of a generic are being installed prior to
7948 -- instantiation. In this case there must be no warning.
7949 -- We detect this case by checking whether the current top
7950 -- of the stack is related to the current compilation.
7952 Scop
:= Current_Scope
;
7953 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7954 if Is_Compilation_Unit
(Scop
)
7955 and then not Is_Child_Unit
(Scop
)
7959 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7963 Scop
:= Scope
(Scop
);
7966 Redundant
:= Cur_Use
;
7970 elsif New_Unit
= Current_Sem_Unit
then
7971 Redundant
:= Clause
;
7972 Prev_Use
:= Cur_Use
;
7975 -- Neither is the current unit, so they appear in parent or
7976 -- sibling units. Warning will be emitted elsewhere.
7982 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
7983 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
7985 -- Use_clause is in child unit of current unit, and the child unit
7986 -- appears in the context of the body of the parent, so it has been
7987 -- installed first, even though it is the redundant one. Depending on
7988 -- their placement in the context, the visible or the private parts
7989 -- of the two units, either might appear as redundant, but the
7990 -- message has to be on the current unit.
7992 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
7993 Redundant
:= Cur_Use
;
7996 Redundant
:= Clause
;
7997 Prev_Use
:= Cur_Use
;
8000 -- If the new use clause appears in the private part of a parent unit
8001 -- it may appear to be redundant w.r.t. a use clause in a child unit,
8002 -- but the previous use clause was needed in the visible part of the
8003 -- child, and no warning should be emitted.
8005 if Nkind
(Parent
(Decl
)) = N_Package_Specification
8007 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
8010 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
8011 Spec
: constant Node_Id
:=
8012 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
8015 if Is_Compilation_Unit
(Par
)
8016 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
8017 and then Parent
(Cur_Use
) = Spec
8019 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
8026 -- Finally, if the current use clause is in the context then
8027 -- the clause is redundant when it is nested within the unit.
8029 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
8030 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
8031 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
8033 Redundant
:= Clause
;
8034 Prev_Use
:= Cur_Use
;
8040 if Present
(Redundant
) then
8041 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
8042 Error_Msg_NE
-- CODEFIX
8043 ("& is already use-visible through previous use clause #??",
8044 Redundant
, Pack_Name
);
8046 end Note_Redundant_Use
;
8052 procedure Pop_Scope
is
8053 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8054 S
: constant Entity_Id
:= SST
.Entity
;
8057 if Debug_Flag_E
then
8061 -- Set Default_Storage_Pool field of the library unit if necessary
8063 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8065 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8068 Aux
: constant Node_Id
:=
8069 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8071 if No
(Default_Storage_Pool
(Aux
)) then
8072 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8077 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8078 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8079 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8080 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8081 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8082 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8083 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8084 Default_SSO
:= SST
.Save_Default_SSO
;
8085 Uneval_Old
:= SST
.Save_Uneval_Old
;
8087 if Debug_Flag_W
then
8088 Write_Str
("<-- exiting scope: ");
8089 Write_Name
(Chars
(Current_Scope
));
8090 Write_Str
(", Depth=");
8091 Write_Int
(Int
(Scope_Stack
.Last
));
8095 End_Use_Clauses
(SST
.First_Use_Clause
);
8097 -- If the actions to be wrapped are still there they will get lost
8098 -- causing incomplete code to be generated. It is better to abort in
8099 -- this case (and we do the abort even with assertions off since the
8100 -- penalty is incorrect code generation).
8102 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8103 raise Program_Error;
8106 -- Free last subprogram name if allocated, and pop scope
8108 Free (SST.Last_Subprogram_Name);
8109 Scope_Stack.Decrement_Last;
8116 procedure Push_Scope (S : Entity_Id) is
8117 E : constant Entity_Id := Scope (S);
8120 if Ekind (S) = E_Void then
8123 -- Set scope depth if not a non-concurrent type, and we have not yet set
8124 -- the scope depth. This means that we have the first occurrence of the
8125 -- scope, and this is where the depth is set.
8127 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8128 and then not Scope_Depth_Set (S)
8130 if S = Standard_Standard then
8131 Set_Scope_Depth_Value (S, Uint_0);
8133 elsif Is_Child_Unit (S) then
8134 Set_Scope_Depth_Value (S, Uint_1);
8136 elsif not Is_Record_Type (Current_Scope) then
8137 if Ekind (S) = E_Loop then
8138 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8140 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8145 Scope_Stack.Increment_Last;
8148 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8152 SST.Save_Scope_Suppress := Scope_Suppress;
8153 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8154 SST.Save_Check_Policy_List := Check_Policy_List;
8155 SST.Save_Default_Storage_Pool := Default_Pool;
8156 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8157 SST.Save_SPARK_Mode := SPARK_Mode;
8158 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8159 SST.Save_Default_SSO := Default_SSO;
8160 SST.Save_Uneval_Old := Uneval_Old;
8162 if Scope_Stack.Last > Scope_Stack.First then
8163 SST.Component_Alignment_Default := Scope_Stack.Table
8164 (Scope_Stack.Last - 1).
8165 Component_Alignment_Default;
8168 SST.Last_Subprogram_Name := null;
8169 SST.Is_Transient := False;
8170 SST.Node_To_Be_Wrapped := Empty;
8171 SST.Pending_Freeze_Actions := No_List;
8172 SST.Actions_To_Be_Wrapped := (others => No_List);
8173 SST.First_Use_Clause := Empty;
8174 SST.Is_Active_Stack_Base := False;
8175 SST.Previous_Visibility := False;
8176 SST.Locked_Shared_Objects := No_Elist;
8179 if Debug_Flag_W then
8180 Write_Str ("--> new scope: ");
8181 Write_Name (Chars (Current_Scope));
8182 Write_Str (", Id=");
8183 Write_Int (Int (Current_Scope));
8184 Write_Str (", Depth=");
8185 Write_Int (Int (Scope_Stack.Last));
8189 -- Deal with copying flags from the previous scope to this one. This is
8190 -- not necessary if either scope is standard, or if the new scope is a
8193 if S /= Standard_Standard
8194 and then Scope (S) /= Standard_Standard
8195 and then not Is_Child_Unit (S)
8197 if Nkind (E) not in N_Entity then
8201 -- Copy categorization flags from Scope (S) to S, this is not done
8202 -- when Scope (S) is Standard_Standard since propagation is from
8203 -- library unit entity inwards. Copy other relevant attributes as
8204 -- well (Discard_Names in particular).
8206 -- We only propagate inwards for library level entities,
8207 -- inner level subprograms do not inherit the categorization.
8209 if Is_Library_Level_Entity (S) then
8210 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8211 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8212 Set_Discard_Names (S, Discard_Names (E));
8213 Set_Suppress_Value_Tracking_On_Call
8214 (S, Suppress_Value_Tracking_On_Call (E));
8215 Set_Categorization_From_Scope (E => S, Scop => E);
8219 if Is_Child_Unit (S)
8220 and then Present (E)
8221 and then Ekind_In (E, E_Package, E_Generic_Package)
8223 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8226 Aux : constant Node_Id :=
8227 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8229 if Present (Default_Storage_Pool (Aux)) then
8230 Default_Pool := Default_Storage_Pool (Aux);
8236 ---------------------
8237 -- Premature_Usage --
8238 ---------------------
8240 procedure Premature_Usage (N : Node_Id) is
8241 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8242 E : Entity_Id := Entity (N);
8245 -- Within an instance, the analysis of the actual for a formal object
8246 -- does not see the name of the object itself. This is significant only
8247 -- if the object is an aggregate, where its analysis does not do any
8248 -- name resolution on component associations. (see 4717-008). In such a
8249 -- case, look for the visible homonym on the chain.
8251 if In_Instance and then Present (Homonym (E)) then
8253 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8259 Set_Etype (N, Etype (E));
8264 if Kind = N_Component_Declaration then
8266 ("component&! cannot be used before end of record declaration", N);
8268 elsif Kind = N_Parameter_Specification then
8270 ("formal parameter&! cannot be used before end of specification",
8273 elsif Kind = N_Discriminant_Specification then
8275 ("discriminant&! cannot be used before end of discriminant part",
8278 elsif Kind = N_Procedure_Specification
8279 or else Kind = N_Function_Specification
8282 ("subprogram&! cannot be used before end of its declaration",
8285 elsif Kind = N_Full_Type_Declaration then
8287 ("type& cannot be used before end of its declaration!", N);
8291 ("object& cannot be used before end of its declaration!", N);
8293 end Premature_Usage;
8295 ------------------------
8296 -- Present_System_Aux --
8297 ------------------------
8299 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8301 Aux_Name : Unit_Name_Type;
8302 Unum : Unit_Number_Type;
8307 function Find_System (C_Unit : Node_Id) return Entity_Id;
8308 -- Scan context clause of compilation unit to find with_clause
8315 function Find_System (C_Unit : Node_Id) return Entity_Id is
8316 With_Clause : Node_Id;
8319 With_Clause := First (Context_Items (C_Unit));
8320 while Present (With_Clause) loop
8321 if (Nkind (With_Clause) = N_With_Clause
8322 and then Chars (Name (With_Clause)) = Name_System)
8323 and then Comes_From_Source (With_Clause)
8334 -- Start of processing for Present_System_Aux
8337 -- The child unit may have been loaded and analyzed already
8339 if Present (System_Aux_Id) then
8342 -- If no previous pragma for System.Aux, nothing to load
8344 elsif No (System_Extend_Unit) then
8347 -- Use the unit name given in the pragma to retrieve the unit.
8348 -- Verify that System itself appears in the context clause of the
8349 -- current compilation. If System is not present, an error will
8350 -- have been reported already.
8353 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8355 The_Unit := Unit (Cunit (Current_Sem_Unit));
8359 (Nkind (The_Unit) = N_Package_Body
8360 or else (Nkind (The_Unit) = N_Subprogram_Body
8361 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8363 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8366 if No (With_Sys) and then Present (N) then
8368 -- If we are compiling a subunit, we need to examine its
8369 -- context as well (Current_Sem_Unit is the parent unit);
8371 The_Unit := Parent (N);
8372 while Nkind (The_Unit) /= N_Compilation_Unit loop
8373 The_Unit := Parent (The_Unit);
8376 if Nkind (Unit (The_Unit)) = N_Subunit then
8377 With_Sys := Find_System (The_Unit);
8381 if No (With_Sys) then
8385 Loc := Sloc (With_Sys);
8386 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8387 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8388 Name_Buffer (1 .. 7) := "system.";
8389 Name_Buffer (Name_Len + 8) := '%';
8390 Name_Buffer (Name_Len + 9) := 's
';
8391 Name_Len := Name_Len + 9;
8392 Aux_Name := Name_Find;
8396 (Load_Name => Aux_Name,
8399 Error_Node => With_Sys);
8401 if Unum /= No_Unit then
8402 Semantics (Cunit (Unum));
8404 Defining_Entity (Specification (Unit (Cunit (Unum))));
8407 Make_With_Clause (Loc,
8409 Make_Expanded_Name (Loc,
8410 Chars => Chars (System_Aux_Id),
8411 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8412 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8414 Set_Entity (Name (Withn), System_Aux_Id);
8416 Set_Library_Unit (Withn, Cunit (Unum));
8417 Set_Corresponding_Spec (Withn, System_Aux_Id);
8418 Set_First_Name (Withn, True);
8419 Set_Implicit_With (Withn, True);
8421 Insert_After (With_Sys, Withn);
8422 Mark_Rewrite_Insertion (Withn);
8423 Set_Context_Installed (Withn);
8427 -- Here if unit load failed
8430 Error_Msg_Name_1 := Name_System;
8431 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8433 ("extension package `%.%` does not exist",
8434 Opt.System_Extend_Unit);
8438 end Present_System_Aux;
8440 -------------------------
8441 -- Restore_Scope_Stack --
8442 -------------------------
8444 procedure Restore_Scope_Stack
8446 Handle_Use : Boolean := True)
8448 SS_Last : constant Int := Scope_Stack.Last;
8452 -- Restore visibility of previous scope stack, if any, using the list
8453 -- we saved (we use Remove, since this list will not be used again).
8456 Elmt := Last_Elmt (List);
8457 exit when Elmt = No_Elmt;
8458 Set_Is_Immediately_Visible (Node (Elmt));
8459 Remove_Last_Elmt (List);
8462 -- Restore use clauses
8464 if SS_Last >= Scope_Stack.First
8465 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8468 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8470 end Restore_Scope_Stack;
8472 ----------------------
8473 -- Save_Scope_Stack --
8474 ----------------------
8476 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8477 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8478 -- from immediate visibility entities and Restore_Scope_Stack took care
8479 -- of restoring their visibility analyzing the context of each entity. The
8480 -- problem of such approach is that it was fragile and caused unexpected
8481 -- visibility problems, and indeed one test was found where there was a
8484 -- Furthermore, the following experiment was carried out:
8486 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8487 -- entities whose attribute Is_Immediately_Visible is modified
8488 -- from True to False.
8490 -- - Restore_Scope_Stack was modified to store in another Elist2
8491 -- all the entities whose attribute Is_Immediately_Visible is
8492 -- modified from False to True.
8494 -- - Extra code was added to verify that all the elements of Elist1
8495 -- are found in Elist2
8497 -- This test shows that there may be more occurrences of this problem which
8498 -- have not yet been detected. As a result, we replaced that approach by
8499 -- the current one in which Save_Scope_Stack returns the list of entities
8500 -- whose visibility is changed, and that list is passed to Restore_Scope_
8501 -- Stack to undo that change. This approach is simpler and safer, although
8502 -- it consumes more memory.
8504 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8505 Result : constant Elist_Id := New_Elmt_List;
8508 SS_Last : constant Int := Scope_Stack.Last;
8510 procedure Remove_From_Visibility (E : Entity_Id);
8511 -- If E is immediately visible then append it to the result and remove
8512 -- it temporarily from visibility.
8514 ----------------------------
8515 -- Remove_From_Visibility --
8516 ----------------------------
8518 procedure Remove_From_Visibility (E : Entity_Id) is
8520 if Is_Immediately_Visible (E) then
8521 Append_Elmt (E, Result);
8522 Set_Is_Immediately_Visible (E, False);
8524 end Remove_From_Visibility;
8526 -- Start of processing for Save_Scope_Stack
8529 if SS_Last >= Scope_Stack.First
8530 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8533 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8536 -- If the call is from within a compilation unit, as when called from
8537 -- Rtsfind, make current entries in scope stack invisible while we
8538 -- analyze the new unit.
8540 for J in reverse 0 .. SS_Last loop
8541 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8542 or else No (Scope_Stack.Table (J).Entity);
8544 S := Scope_Stack.Table (J).Entity;
8546 Remove_From_Visibility (S);
8548 E := First_Entity (S);
8549 while Present (E) loop
8550 Remove_From_Visibility (E);
8558 end Save_Scope_Stack;
8564 procedure Set_Use (L : List_Id) is
8566 Pack_Name : Node_Id;
8573 while Present (Decl) loop
8574 if Nkind (Decl) = N_Use_Package_Clause then
8575 Chain_Use_Clause (Decl);
8577 Pack_Name := First (Names (Decl));
8578 while Present (Pack_Name) loop
8579 Pack := Entity (Pack_Name);
8581 if Ekind (Pack) = E_Package
8582 and then Applicable_Use (Pack_Name)
8584 Use_One_Package (Pack, Decl);
8590 elsif Nkind (Decl) = N_Use_Type_Clause then
8591 Chain_Use_Clause (Decl);
8593 Id := First (Subtype_Marks (Decl));
8594 while Present (Id) loop
8595 if Entity (Id) /= Any_Type then
8608 ---------------------
8609 -- Use_One_Package --
8610 ---------------------
8612 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8615 Current_Instance : Entity_Id := Empty;
8617 Private_With_OK : Boolean := False;
8620 if Ekind (P) /= E_Package then
8625 Set_Current_Use_Clause (P, N);
8627 -- Ada 2005 (AI-50217): Check restriction
8629 if From_Limited_With (P) then
8630 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8633 -- Find enclosing instance, if any
8636 Current_Instance := Current_Scope;
8637 while not Is_Generic_Instance (Current_Instance) loop
8638 Current_Instance := Scope (Current_Instance);
8641 if No (Hidden_By_Use_Clause (N)) then
8642 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8646 -- If unit is a package renaming, indicate that the renamed
8647 -- package is also in use (the flags on both entities must
8648 -- remain consistent, and a subsequent use of either of them
8649 -- should be recognized as redundant).
8651 if Present (Renamed_Object (P)) then
8652 Set_In_Use (Renamed_Object (P));
8653 Set_Current_Use_Clause (Renamed_Object (P), N);
8654 Real_P := Renamed_Object (P);
8659 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8660 -- found in the private part of a package specification
8662 if In_Private_Part (Current_Scope)
8663 and then Has_Private_With (P)
8664 and then Is_Child_Unit (Current_Scope)
8665 and then Is_Child_Unit (P)
8666 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8668 Private_With_OK := True;
8671 -- Loop through entities in one package making them potentially
8674 Id := First_Entity (P);
8676 and then (Id /= First_Private_Entity (P)
8677 or else Private_With_OK) -- Ada 2005 (AI-262)
8679 Prev := Current_Entity (Id);
8680 while Present (Prev) loop
8681 if Is_Immediately_Visible (Prev)
8682 and then (not Is_Overloadable (Prev)
8683 or else not Is_Overloadable (Id)
8684 or else (Type_Conformant (Id, Prev)))
8686 if No (Current_Instance) then
8688 -- Potentially use-visible entity remains hidden
8690 goto Next_Usable_Entity;
8692 -- A use clause within an instance hides outer global entities,
8693 -- which are not used to resolve local entities in the
8694 -- instance. Note that the predefined entities in Standard
8695 -- could not have been hidden in the generic by a use clause,
8696 -- and therefore remain visible. Other compilation units whose
8697 -- entities appear in Standard must be hidden in an instance.
8699 -- To determine whether an entity is external to the instance
8700 -- we compare the scope depth of its scope with that of the
8701 -- current instance. However, a generic actual of a subprogram
8702 -- instance is declared in the wrapper package but will not be
8703 -- hidden by a use-visible entity. similarly, an entity that is
8704 -- declared in an enclosing instance will not be hidden by an
8705 -- an entity declared in a generic actual, which can only have
8706 -- been use-visible in the generic and will not have hidden the
8707 -- entity in the generic parent.
8709 -- If Id is called Standard, the predefined package with the
8710 -- same name is in the homonym chain. It has to be ignored
8711 -- because it has no defined scope (being the only entity in
8712 -- the system with this mandated behavior).
8714 elsif not Is_Hidden (Id)
8715 and then Present (Scope (Prev))
8716 and then not Is_Wrapper_Package (Scope (Prev))
8717 and then Scope_Depth (Scope (Prev)) <
8718 Scope_Depth (Current_Instance)
8719 and then (Scope (Prev) /= Standard_Standard
8720 or else Sloc (Prev) > Standard_Location)
8722 if In_Open_Scopes (Scope (Prev))
8723 and then Is_Generic_Instance (Scope (Prev))
8724 and then Present (Associated_Formal_Package (P))
8729 Set_Is_Potentially_Use_Visible (Id);
8730 Set_Is_Immediately_Visible (Prev, False);
8731 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8735 -- A user-defined operator is not use-visible if the predefined
8736 -- operator for the type is immediately visible, which is the case
8737 -- if the type of the operand is in an open scope. This does not
8738 -- apply to user-defined operators that have operands of different
8739 -- types, because the predefined mixed mode operations (multiply
8740 -- and divide) apply to universal types and do not hide anything.
8742 elsif Ekind (Prev) = E_Operator
8743 and then Operator_Matches_Spec (Prev, Id)
8744 and then In_Open_Scopes
8745 (Scope (Base_Type (Etype (First_Formal (Id)))))
8746 and then (No (Next_Formal (First_Formal (Id)))
8747 or else Etype (First_Formal (Id)) =
8748 Etype (Next_Formal (First_Formal (Id)))
8749 or else Chars (Prev) = Name_Op_Expon)
8751 goto Next_Usable_Entity;
8753 -- In an instance, two homonyms may become use_visible through the
8754 -- actuals of distinct formal packages. In the generic, only the
8755 -- current one would have been visible, so make the other one
8758 elsif Present (Current_Instance)
8759 and then Is_Potentially_Use_Visible (Prev)
8760 and then not Is_Overloadable (Prev)
8761 and then Scope (Id) /= Scope (Prev)
8762 and then Used_As_Generic_Actual (Scope (Prev))
8763 and then Used_As_Generic_Actual (Scope (Id))
8764 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8765 Current_Use_Clause (Scope (Id)))
8767 Set_Is_Potentially_Use_Visible (Prev, False);
8768 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8771 Prev := Homonym (Prev);
8774 -- On exit, we know entity is not hidden, unless it is private
8776 if not Is_Hidden (Id)
8777 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8779 Set_Is_Potentially_Use_Visible (Id);
8781 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8782 Set_Is_Potentially_Use_Visible (Full_View (Id));
8786 <<Next_Usable_Entity>>
8790 -- Child units are also made use-visible by a use clause, but they may
8791 -- appear after all visible declarations in the parent entity list.
8793 while Present (Id) loop
8794 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8795 Set_Is_Potentially_Use_Visible (Id);
8801 if Chars (Real_P) = Name_System
8802 and then Scope (Real_P) = Standard_Standard
8803 and then Present_System_Aux (N)
8805 Use_One_Package (System_Aux_Id, N);
8808 end Use_One_Package;
8814 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8816 Is_Known_Used : Boolean;
8820 function Spec_Reloaded_For_Body return Boolean;
8821 -- Determine whether the compilation unit is a package body and the use
8822 -- type clause is in the spec of the same package. Even though the spec
8823 -- was analyzed first, its context is reloaded when analysing the body.
8825 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8826 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8827 -- class-wide operations of ancestor types are use-visible if the
8828 -- ancestor type is visible.
8830 ----------------------------
8831 -- Spec_Reloaded_For_Body --
8832 ----------------------------
8834 function Spec_Reloaded_For_Body return Boolean is
8836 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8838 Spec : constant Node_Id :=
8839 Parent (List_Containing (Parent (Id)));
8842 -- Check whether type is declared in a package specification,
8843 -- and current unit is the corresponding package body. The
8844 -- use clauses themselves may be within a nested package.
8847 Nkind (Spec) = N_Package_Specification
8849 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8850 Cunit_Entity (Current_Sem_Unit));
8855 end Spec_Reloaded_For_Body;
8857 -------------------------------
8858 -- Use_Class_Wide_Operations --
8859 -------------------------------
8861 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8865 function Is_Class_Wide_Operation_Of
8867 T : Entity_Id) return Boolean;
8868 -- Determine whether a subprogram has a class-wide parameter or
8869 -- result that is T'Class.
8871 ---------------------------------
8872 -- Is_Class_Wide_Operation_Of --
8873 ---------------------------------
8875 function Is_Class_Wide_Operation_Of
8877 T : Entity_Id) return Boolean
8882 Formal := First_Formal (Op);
8883 while Present (Formal) loop
8884 if Etype (Formal) = Class_Wide_Type (T) then
8887 Next_Formal (Formal);
8890 if Etype (Op) = Class_Wide_Type (T) then
8895 end Is_Class_Wide_Operation_Of;
8897 -- Start of processing for Use_Class_Wide_Operations
8900 Scop := Scope (Typ);
8901 if not Is_Hidden (Scop) then
8902 Ent := First_Entity (Scop);
8903 while Present (Ent) loop
8904 if Is_Overloadable (Ent)
8905 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8906 and then not Is_Potentially_Use_Visible (Ent)
8908 Set_Is_Potentially_Use_Visible (Ent);
8909 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8916 if Is_Derived_Type (Typ) then
8917 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8919 end Use_Class_Wide_Operations;
8921 -- Start of processing for Use_One_Type
8924 -- It is the type determined by the subtype mark (8.4(8)) whose
8925 -- operations become potentially use-visible.
8927 T := Base_Type (Entity (Id));
8929 -- Either the type itself is used, the package where it is declared
8930 -- is in use or the entity is declared in the current package, thus
8935 or else In_Use (Scope (T))
8936 or else Scope (T) = Current_Scope;
8938 Set_Redundant_Use (Id,
8939 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8941 if Ekind (T) = E_Incomplete_Type then
8942 Error_Msg_N ("premature usage of incomplete type", Id);
8944 elsif In_Open_Scopes (Scope (T)) then
8947 -- A limited view cannot appear in a use_type clause. However, an access
8948 -- type whose designated type is limited has the flag but is not itself
8949 -- a limited view unless we only have a limited view of its enclosing
8952 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8954 ("incomplete type from limited view "
8955 & "cannot appear in use clause", Id);
8957 -- If the subtype mark designates a subtype in a different package,
8958 -- we have to check that the parent type is visible, otherwise the
8959 -- use type clause is a noop. Not clear how to do that???
8961 elsif not Redundant_Use (Id) then
8964 -- If T is tagged, primitive operators on class-wide operands
8965 -- are also available.
8967 if Is_Tagged_Type (T) then
8968 Set_In_Use (Class_Wide_Type (T));
8971 Set_Current_Use_Clause (T, Parent (Id));
8973 -- Iterate over primitive operations of the type. If an operation is
8974 -- already use_visible, it is the result of a previous use_clause,
8975 -- and already appears on the corresponding entity chain. If the
8976 -- clause is being reinstalled, operations are already use-visible.
8982 Op_List := Collect_Primitive_Operations (T);
8983 Elmt := First_Elmt (Op_List);
8984 while Present (Elmt) loop
8985 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
8986 or else Chars (Node (Elmt)) in Any_Operator_Name)
8987 and then not Is_Hidden (Node (Elmt))
8988 and then not Is_Potentially_Use_Visible (Node (Elmt))
8990 Set_Is_Potentially_Use_Visible (Node (Elmt));
8991 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8993 elsif Ada_Version >= Ada_2012
8994 and then All_Present (Parent (Id))
8995 and then not Is_Hidden (Node (Elmt))
8996 and then not Is_Potentially_Use_Visible (Node (Elmt))
8998 Set_Is_Potentially_Use_Visible (Node (Elmt));
8999 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9006 if Ada_Version >= Ada_2012
9007 and then All_Present (Parent (Id))
9008 and then Is_Tagged_Type (T)
9010 Use_Class_Wide_Operations (T);
9014 -- If warning on redundant constructs, check for unnecessary WITH
9016 if Warn_On_Redundant_Constructs
9017 and then Is_Known_Used
9019 -- with P; with P; use P;
9020 -- package P is package X is package body X is
9021 -- type T ... use P.T;
9023 -- The compilation unit is the body of X. GNAT first compiles the
9024 -- spec of X, then proceeds to the body. At that point P is marked
9025 -- as use visible. The analysis then reinstalls the spec along with
9026 -- its context. The use clause P.T is now recognized as redundant,
9027 -- but in the wrong context. Do not emit a warning in such cases.
9028 -- Do not emit a warning either if we are in an instance, there is
9029 -- no redundancy between an outer use_clause and one that appears
9030 -- within the generic.
9032 and then not Spec_Reloaded_For_Body
9033 and then not In_Instance
9035 -- The type already has a use clause
9039 -- Case where we know the current use clause for the type
9041 if Present (Current_Use_Clause (T)) then
9042 Use_Clause_Known : declare
9043 Clause1 : constant Node_Id := Parent (Id);
9044 Clause2 : constant Node_Id := Current_Use_Clause (T);
9051 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9052 -- Return the appropriate entity for determining which unit
9053 -- has a deeper scope: the defining entity for U, unless U
9054 -- is a package instance, in which case we retrieve the
9055 -- entity of the instance spec.
9057 --------------------
9058 -- Entity_Of_Unit --
9059 --------------------
9061 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9063 if Nkind (U) = N_Package_Instantiation
9064 and then Analyzed (U)
9066 return Defining_Entity (Instance_Spec (U));
9068 return Defining_Entity (U);
9072 -- Start of processing for Use_Clause_Known
9075 -- If both current use type clause and the use type clause
9076 -- for the type are at the compilation unit level, one of
9077 -- the units must be an ancestor of the other, and the
9078 -- warning belongs on the descendant.
9080 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9082 Nkind (Parent (Clause2)) = N_Compilation_Unit
9084 -- If the unit is a subprogram body that acts as spec,
9085 -- the context clause is shared with the constructed
9086 -- subprogram spec. Clearly there is no redundancy.
9088 if Clause1 = Clause2 then
9092 Unit1 := Unit (Parent (Clause1));
9093 Unit2 := Unit (Parent (Clause2));
9095 -- If both clauses are on same unit, or one is the body
9096 -- of the other, or one of them is in a subunit, report
9097 -- redundancy on the later one.
9099 if Unit1 = Unit2 then
9100 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9101 Error_Msg_NE -- CODEFIX
9102 ("& is already use-visible through previous "
9103 & "use_type_clause #??", Clause1, T);
9106 elsif Nkind (Unit1) = N_Subunit then
9107 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9108 Error_Msg_NE -- CODEFIX
9109 ("& is already use-visible through previous "
9110 & "use_type_clause #??", Clause1, T);
9113 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9114 and then Nkind (Unit1) /= Nkind (Unit2)
9115 and then Nkind (Unit1) /= N_Subunit
9117 Error_Msg_Sloc := Sloc (Clause1);
9118 Error_Msg_NE -- CODEFIX
9119 ("& is already use-visible through previous "
9120 & "use_type_clause #??", Current_Use_Clause (T), T);
9124 -- There is a redundant use type clause in a child unit.
9125 -- Determine which of the units is more deeply nested.
9126 -- If a unit is a package instance, retrieve the entity
9127 -- and its scope from the instance spec.
9129 Ent1 := Entity_Of_Unit (Unit1);
9130 Ent2 := Entity_Of_Unit (Unit2);
9132 if Scope (Ent2) = Standard_Standard then
9133 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9136 elsif Scope (Ent1) = Standard_Standard then
9137 Error_Msg_Sloc := Sloc (Id);
9140 -- If both units are child units, we determine which one
9141 -- is the descendant by the scope distance to the
9142 -- ultimate parent unit.
9152 and then Present (S2)
9153 and then S1 /= Standard_Standard
9154 and then S2 /= Standard_Standard
9160 if S1 = Standard_Standard then
9161 Error_Msg_Sloc := Sloc (Id);
9164 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9170 Error_Msg_NE -- CODEFIX
9171 ("& is already use-visible through previous "
9172 & "use_type_clause #??", Err_No, Id);
9174 -- Case where current use type clause and the use type
9175 -- clause for the type are not both at the compilation unit
9176 -- level. In this case we don't have location information.
9179 Error_Msg_NE -- CODEFIX
9180 ("& is already use-visible through previous "
9181 & "use type clause??", Id, T);
9183 end Use_Clause_Known;
9185 -- Here if Current_Use_Clause is not set for T, another case
9186 -- where we do not have the location information available.
9189 Error_Msg_NE -- CODEFIX
9190 ("& is already use-visible through previous "
9191 & "use type clause??", Id, T);
9194 -- The package where T is declared is already used
9196 elsif In_Use (Scope (T)) then
9197 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9198 Error_Msg_NE -- CODEFIX
9199 ("& is already use-visible through package use clause #??",
9202 -- The current scope is the package where T is declared
9205 Error_Msg_Node_2 := Scope (T);
9206 Error_Msg_NE -- CODEFIX
9207 ("& is already use-visible inside package &??", Id, T);
9216 procedure Write_Info is
9217 Id : Entity_Id := First_Entity (Current_Scope);
9220 -- No point in dumping standard entities
9222 if Current_Scope = Standard_Standard then
9226 Write_Str ("========================================================");
9228 Write_Str (" Defined Entities in ");
9229 Write_Name (Chars (Current_Scope));
9231 Write_Str ("========================================================");
9235 Write_Str ("-- none --");
9239 while Present (Id) loop
9240 Write_Entity_Info (Id, " ");
9245 if Scope (Current_Scope) = Standard_Standard then
9247 -- Print information on the current unit itself
9249 Write_Entity_Info (Current_Scope, " ");
9262 for J in reverse 1 .. Scope_Stack.Last loop
9263 S := Scope_Stack.Table (J).Entity;
9264 Write_Int (Int (S));
9265 Write_Str (" === ");
9266 Write_Name (Chars (S));
9275 procedure we (S : Entity_Id) is
9278 E := First_Entity (S);
9279 while Present (E) loop
9280 Write_Int (Int (E));
9281 Write_Str (" === ");
9282 Write_Name (Chars (E));