1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with 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_Tss; use Exp_Tss;
32 with Exp_Util; use Exp_Util;
33 with Fname; use Fname;
34 with Freeze; use Freeze;
35 with Impunit; use Impunit;
37 with Lib.Load; use Lib.Load;
38 with Lib.Xref; use Lib.Xref;
39 with Namet; use Namet;
40 with Namet.Sp; use Namet.Sp;
41 with Nlists; use Nlists;
42 with Nmake; use Nmake;
44 with Output; use Output;
45 with Restrict; use Restrict;
46 with Rident; use Rident;
47 with Rtsfind; use Rtsfind;
49 with Sem_Aux; use Sem_Aux;
50 with Sem_Cat; use Sem_Cat;
51 with Sem_Ch3; use Sem_Ch3;
52 with Sem_Ch4; use Sem_Ch4;
53 with Sem_Ch6; use Sem_Ch6;
54 with Sem_Ch12; use Sem_Ch12;
55 with Sem_Ch13; use Sem_Ch13;
56 with Sem_Dim; use Sem_Dim;
57 with Sem_Disp; use Sem_Disp;
58 with Sem_Dist; use Sem_Dist;
59 with Sem_Eval; use Sem_Eval;
60 with Sem_Res; use Sem_Res;
61 with Sem_Util; use Sem_Util;
62 with Sem_Type; use Sem_Type;
63 with Stand; use Stand;
64 with Sinfo; use Sinfo;
65 with Sinfo.CN; use Sinfo.CN;
66 with Snames; use Snames;
67 with Style; use Style;
69 with Targparm; use Targparm;
70 with Tbuild; use Tbuild;
71 with Uintp; use Uintp;
73 package body Sem_Ch8 is
75 ------------------------------------
76 -- Visibility and Name Resolution --
77 ------------------------------------
79 -- This package handles name resolution and the collection of possible
80 -- interpretations for overloaded names, prior to overload resolution.
82 -- Name resolution is the process that establishes a mapping between source
83 -- identifiers and the entities they denote at each point in the program.
84 -- Each entity is represented by a defining occurrence. Each identifier
85 -- that denotes an entity points to the corresponding defining occurrence.
86 -- This is the entity of the applied occurrence. Each occurrence holds
87 -- an index into the names table, where source identifiers are stored.
89 -- Each entry in the names table for an identifier or designator uses the
90 -- Info pointer to hold a link to the currently visible entity that has
91 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
92 -- in package Sem_Util). The visibility is initialized at the beginning of
93 -- semantic processing to make entities in package Standard immediately
94 -- visible. The visibility table is used in a more subtle way when
95 -- compiling subunits (see below).
97 -- Entities that have the same name (i.e. homonyms) are chained. In the
98 -- case of overloaded entities, this chain holds all the possible meanings
99 -- of a given identifier. The process of overload resolution uses type
100 -- information to select from this chain the unique meaning of a given
103 -- Entities are also chained in their scope, through the Next_Entity link.
104 -- As a consequence, the name space is organized as a sparse matrix, where
105 -- each row corresponds to a scope, and each column to a source identifier.
106 -- Open scopes, that is to say scopes currently being compiled, have their
107 -- corresponding rows of entities in order, innermost scope first.
109 -- The scopes of packages that are mentioned in context clauses appear in
110 -- no particular order, interspersed among open scopes. This is because
111 -- in the course of analyzing the context of a compilation, a package
112 -- declaration is first an open scope, and subsequently an element of the
113 -- context. If subunits or child units are present, a parent unit may
114 -- appear under various guises at various times in the compilation.
116 -- When the compilation of the innermost scope is complete, the entities
117 -- defined therein are no longer visible. If the scope is not a package
118 -- declaration, these entities are never visible subsequently, and can be
119 -- removed from visibility chains. If the scope is a package declaration,
120 -- its visible declarations may still be accessible. Therefore the entities
121 -- defined in such a scope are left on the visibility chains, and only
122 -- their visibility (immediately visibility or potential use-visibility)
125 -- The ordering of homonyms on their chain does not necessarily follow
126 -- the order of their corresponding scopes on the scope stack. For
127 -- example, if package P and the enclosing scope both contain entities
128 -- named E, then when compiling the package body the chain for E will
129 -- hold the global entity first, and the local one (corresponding to
130 -- the current inner scope) next. As a result, name resolution routines
131 -- do not assume any relative ordering of the homonym chains, either
132 -- for scope nesting or to order of appearance of context clauses.
134 -- When compiling a child unit, entities in the parent scope are always
135 -- immediately visible. When compiling the body of a child unit, private
136 -- entities in the parent must also be made immediately visible. There
137 -- are separate routines to make the visible and private declarations
138 -- visible at various times (see package Sem_Ch7).
140 -- +--------+ +-----+
141 -- | In use |-------->| EU1 |-------------------------->
142 -- +--------+ +-----+
144 -- +--------+ +-----+ +-----+
145 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
146 -- +--------+ +-----+ +-----+
148 -- +---------+ | +-----+
149 -- | with'ed |------------------------------>| EW2 |--->
150 -- +---------+ | +-----+
152 -- +--------+ +-----+ +-----+
153 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
154 -- +--------+ +-----+ +-----+
156 -- +--------+ +-----+ +-----+
157 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
158 -- +--------+ +-----+ +-----+
162 -- | | with'ed |----------------------------------------->
166 -- (innermost first) | |
167 -- +----------------------------+
168 -- Names table => | Id1 | | | | Id2 |
169 -- +----------------------------+
171 -- Name resolution must deal with several syntactic forms: simple names,
172 -- qualified names, indexed names, and various forms of calls.
174 -- Each identifier points to an entry in the names table. The resolution
175 -- of a simple name consists in traversing the homonym chain, starting
176 -- from the names table. If an entry is immediately visible, it is the one
177 -- designated by the identifier. If only potentially use-visible entities
178 -- are on the chain, we must verify that they do not hide each other. If
179 -- the entity we find is overloadable, we collect all other overloadable
180 -- entities on the chain as long as they are not hidden.
182 -- To resolve expanded names, we must find the entity at the intersection
183 -- of the entity chain for the scope (the prefix) and the homonym chain
184 -- for the selector. In general, homonym chains will be much shorter than
185 -- entity chains, so it is preferable to start from the names table as
186 -- well. If the entity found is overloadable, we must collect all other
187 -- interpretations that are defined in the scope denoted by the prefix.
189 -- For records, protected types, and tasks, their local entities are
190 -- removed from visibility chains on exit from the corresponding scope.
191 -- From the outside, these entities are always accessed by selected
192 -- notation, and the entity chain for the record type, protected type,
193 -- etc. is traversed sequentially in order to find the designated entity.
195 -- The discriminants of a type and the operations of a protected type or
196 -- task are unchained on exit from the first view of the type, (such as
197 -- a private or incomplete type declaration, or a protected type speci-
198 -- fication) and re-chained when compiling the second view.
200 -- In the case of operators, we do not make operators on derived types
201 -- explicit. As a result, the notation P."+" may denote either a user-
202 -- defined function with name "+", or else an implicit declaration of the
203 -- operator "+" in package P. The resolution of expanded names always
204 -- tries to resolve an operator name as such an implicitly defined entity,
205 -- in addition to looking for explicit declarations.
207 -- All forms of names that denote entities (simple names, expanded names,
208 -- character literals in some cases) have a Entity attribute, which
209 -- identifies the entity denoted by the name.
211 ---------------------
212 -- The Scope Stack --
213 ---------------------
215 -- The Scope stack keeps track of the scopes currently been compiled.
216 -- Every entity that contains declarations (including records) is placed
217 -- on the scope stack while it is being processed, and removed at the end.
218 -- Whenever a non-package scope is exited, the entities defined therein
219 -- are removed from the visibility table, so that entities in outer scopes
220 -- become visible (see previous description). On entry to Sem, the scope
221 -- stack only contains the package Standard. As usual, subunits complicate
222 -- this picture ever so slightly.
224 -- The Rtsfind mechanism can force a call to Semantics while another
225 -- compilation is in progress. The unit retrieved by Rtsfind must be
226 -- compiled in its own context, and has no access to the visibility of
227 -- the unit currently being compiled. The procedures Save_Scope_Stack and
228 -- Restore_Scope_Stack make entities in current open scopes invisible
229 -- before compiling the retrieved unit, and restore the compilation
230 -- environment afterwards.
232 ------------------------
233 -- Compiling subunits --
234 ------------------------
236 -- Subunits must be compiled in the environment of the corresponding stub,
237 -- that is to say with the same visibility into the parent (and its
238 -- context) that is available at the point of the stub declaration, but
239 -- with the additional visibility provided by the context clause of the
240 -- subunit itself. As a result, compilation of a subunit forces compilation
241 -- of the parent (see description in lib-). At the point of the stub
242 -- declaration, Analyze is called recursively to compile the proper body of
243 -- the subunit, but without reinitializing the names table, nor the scope
244 -- stack (i.e. standard is not pushed on the stack). In this fashion the
245 -- context of the subunit is added to the context of the parent, and the
246 -- subunit is compiled in the correct environment. Note that in the course
247 -- of processing the context of a subunit, Standard will appear twice on
248 -- the scope stack: once for the parent of the subunit, and once for the
249 -- unit in the context clause being compiled. However, the two sets of
250 -- entities are not linked by homonym chains, so that the compilation of
251 -- any context unit happens in a fresh visibility environment.
253 -------------------------------
254 -- Processing of USE Clauses --
255 -------------------------------
257 -- Every defining occurrence has a flag indicating if it is potentially use
258 -- visible. Resolution of simple names examines this flag. The processing
259 -- of use clauses consists in setting this flag on all visible entities
260 -- defined in the corresponding package. On exit from the scope of the use
261 -- clause, the corresponding flag must be reset. However, a package may
262 -- appear in several nested use clauses (pathological but legal, alas)
263 -- which forces us to use a slightly more involved scheme:
265 -- a) The defining occurrence for a package holds a flag -In_Use- to
266 -- indicate that it is currently in the scope of a use clause. If a
267 -- redundant use clause is encountered, then the corresponding occurrence
268 -- of the package name is flagged -Redundant_Use-.
270 -- b) On exit from a scope, the use clauses in its declarative part are
271 -- scanned. The visibility flag is reset in all entities declared in
272 -- package named in a use clause, as long as the package is not flagged
273 -- as being in a redundant use clause (in which case the outer use
274 -- clause is still in effect, and the direct visibility of its entities
275 -- must be retained).
277 -- Note that entities are not removed from their homonym chains on exit
278 -- from the package specification. A subsequent use clause does not need
279 -- to rechain the visible entities, but only to establish their direct
282 -----------------------------------
283 -- Handling private declarations --
284 -----------------------------------
286 -- The principle that each entity has a single defining occurrence clashes
287 -- with the presence of two separate definitions for private types: the
288 -- first is the private type declaration, and second is the full type
289 -- declaration. It is important that all references to the type point to
290 -- the same defining occurrence, namely the first one. To enforce the two
291 -- separate views of the entity, the corresponding information is swapped
292 -- between the two declarations. Outside of the package, the defining
293 -- occurrence only contains the private declaration information, while in
294 -- the private part and the body of the package the defining occurrence
295 -- contains the full declaration. To simplify the swap, the defining
296 -- occurrence that currently holds the private declaration points to the
297 -- full declaration. During semantic processing the defining occurrence
298 -- also points to a list of private dependents, that is to say access types
299 -- or composite types whose designated types or component types are
300 -- subtypes or derived types of the private type in question. After the
301 -- full declaration has been seen, the private dependents are updated to
302 -- indicate that they have full definitions.
304 ------------------------------------
305 -- Handling of Undefined Messages --
306 ------------------------------------
308 -- In normal mode, only the first use of an undefined identifier generates
309 -- a message. The table Urefs is used to record error messages that have
310 -- been issued so that second and subsequent ones do not generate further
311 -- messages. However, the second reference causes text to be added to the
312 -- original undefined message noting "(more references follow)". The
313 -- full error list option (-gnatf) forces messages to be generated for
314 -- every reference and disconnects the use of this table.
316 type Uref_Entry is record
318 -- Node for identifier for which original message was posted. The
319 -- Chars field of this identifier is used to detect later references
320 -- to the same identifier.
323 -- Records error message Id of original undefined message. Reset to
324 -- No_Error_Msg after the second occurrence, where it is used to add
325 -- text to the original message as described above.
328 -- Set if the message is not visible rather than undefined
331 -- Records location of error message. Used to make sure that we do
332 -- not consider a, b : undefined as two separate instances, which
333 -- would otherwise happen, since the parser converts this sequence
334 -- to a : undefined; b : undefined.
338 package Urefs is new Table.Table (
339 Table_Component_Type => Uref_Entry,
340 Table_Index_Type => Nat,
341 Table_Low_Bound => 1,
343 Table_Increment => 100,
344 Table_Name => "Urefs");
346 Candidate_Renaming : Entity_Id;
347 -- Holds a candidate interpretation that appears in a subprogram renaming
348 -- declaration and does not match the given specification, but matches at
349 -- least on the first formal. Allows better error message when given
350 -- specification omits defaulted parameters, a common error.
352 -----------------------
353 -- Local Subprograms --
354 -----------------------
356 procedure Analyze_Generic_Renaming
359 -- Common processing for all three kinds of generic renaming declarations.
360 -- Enter new name and indicate that it renames the generic unit.
362 procedure Analyze_Renamed_Character
366 -- Renamed entity is given by a character literal, which must belong
367 -- to the return type of the new entity. Is_Body indicates whether the
368 -- declaration is a renaming_as_body. If the original declaration has
369 -- already been frozen (because of an intervening body, e.g.) the body of
370 -- the function must be built now. The same applies to the following
371 -- various renaming procedures.
373 procedure Analyze_Renamed_Dereference
377 -- Renamed entity is given by an explicit dereference. Prefix must be a
378 -- conformant access_to_subprogram type.
380 procedure Analyze_Renamed_Entry
384 -- If the renamed entity in a subprogram renaming is an entry or protected
385 -- subprogram, build a body for the new entity whose only statement is a
386 -- call to the renamed entity.
388 procedure Analyze_Renamed_Family_Member
392 -- Used when the renamed entity is an indexed component. The prefix must
393 -- denote an entry family.
395 procedure Analyze_Renamed_Primitive_Operation
399 -- If the renamed entity in a subprogram renaming is a primitive operation
400 -- or a class-wide operation in prefix form, save the target object,
401 -- which must be added to the list of actuals in any subsequent call.
402 -- The renaming operation is intrinsic because the compiler must in
403 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
405 function Applicable_Use (Pack_Name : Node_Id) return Boolean;
406 -- Common code to Use_One_Package and Set_Use, to determine whether use
407 -- clause must be processed. Pack_Name is an entity name that references
408 -- the package in question.
410 procedure Attribute_Renaming (N : Node_Id);
411 -- Analyze renaming of attribute as subprogram. The renaming declaration N
412 -- is rewritten as a subprogram body that returns the attribute reference
413 -- applied to the formals of the function.
415 procedure Set_Entity_Or_Discriminal (N : Node_Id; E : Entity_Id);
416 -- Set Entity, with style check if need be. For a discriminant reference,
417 -- replace by the corresponding discriminal, i.e. the parameter of the
418 -- initialization procedure that corresponds to the discriminant.
420 procedure Check_Frozen_Renaming (N : Node_Id; Subp : Entity_Id);
421 -- A renaming_as_body may occur after the entity of the original decla-
422 -- ration has been frozen. In that case, the body of the new entity must
423 -- be built now, because the usual mechanism of building the renamed
424 -- body at the point of freezing will not work. Subp is the subprogram
425 -- for which N provides the Renaming_As_Body.
427 procedure Check_In_Previous_With_Clause
430 -- N is a use_package clause and Nam the package name, or N is a use_type
431 -- clause and Nam is the prefix of the type name. In either case, verify
432 -- that the package is visible at that point in the context: either it
433 -- appears in a previous with_clause, or because it is a fully qualified
434 -- name and the root ancestor appears in a previous with_clause.
436 procedure Check_Library_Unit_Renaming (N : Node_Id; Old_E : Entity_Id);
437 -- Verify that the entity in a renaming declaration that is a library unit
438 -- is itself a library unit and not a nested unit or subunit. Also check
439 -- that if the renaming is a child unit of a generic parent, then the
440 -- renamed unit must also be a child unit of that parent. Finally, verify
441 -- that a renamed generic unit is not an implicit child declared within
442 -- an instance of the parent.
444 procedure Chain_Use_Clause (N : Node_Id);
445 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
446 -- the proper scope table entry. This is usually the current scope, but it
447 -- will be an inner scope when installing the use clauses of the private
448 -- declarations of a parent unit prior to compiling the private part of a
449 -- child unit. This chain is traversed when installing/removing use clauses
450 -- when compiling a subunit or instantiating a generic body on the fly,
451 -- when it is necessary to save and restore full environments.
453 function Enclosing_Instance return Entity_Id;
454 -- In an instance nested within another one, several semantic checks are
455 -- unnecessary because the legality of the nested instance has been checked
456 -- in the enclosing generic unit. This applies in particular to legality
457 -- checks on actuals for formal subprograms of the inner instance, which
458 -- are checked as subprogram renamings, and may be complicated by confusion
459 -- in private/full views. This function returns the instance enclosing the
460 -- current one if there is such, else it returns Empty.
462 -- If the renaming determines the entity for the default of a formal
463 -- subprogram nested within another instance, choose the innermost
464 -- candidate. This is because if the formal has a box, and we are within
465 -- an enclosing instance where some candidate interpretations are local
466 -- to this enclosing instance, we know that the default was properly
467 -- resolved when analyzing the generic, so we prefer the local
468 -- candidates to those that are external. This is not always the case
469 -- but is a reasonable heuristic on the use of nested generics. The
470 -- proper solution requires a full renaming model.
472 function Has_Implicit_Character_Literal (N : Node_Id) return Boolean;
473 -- Find a type derived from Character or Wide_Character in the prefix of N.
474 -- Used to resolved qualified names whose selector is a character literal.
476 function Has_Private_With (E : Entity_Id) return Boolean;
477 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
478 -- private with on E.
480 procedure Find_Expanded_Name (N : Node_Id);
481 -- The input is a selected component known to be an expanded name. Verify
482 -- legality of selector given the scope denoted by prefix, and change node
483 -- N into a expanded name with a properly set Entity field.
485 function Find_Renamed_Entity
489 Is_Actual : Boolean := False) return Entity_Id;
490 -- Find the renamed entity that corresponds to the given parameter profile
491 -- in a subprogram renaming declaration. The renamed entity may be an
492 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
493 -- indicates that the renaming is the one generated for an actual subpro-
494 -- gram in an instance, for which special visibility checks apply.
496 function Has_Implicit_Operator (N : Node_Id) return Boolean;
497 -- N is an expanded name whose selector is an operator name (e.g. P."+").
498 -- declarative part contains an implicit declaration of an operator if it
499 -- has a declaration of a type to which one of the predefined operators
500 -- apply. The existence of this routine is an implementation artifact. A
501 -- more straightforward but more space-consuming choice would be to make
502 -- all inherited operators explicit in the symbol table.
504 procedure Inherit_Renamed_Profile (New_S : Entity_Id; Old_S : Entity_Id);
505 -- A subprogram defined by a renaming declaration inherits the parameter
506 -- profile of the renamed entity. The subtypes given in the subprogram
507 -- specification are discarded and replaced with those of the renamed
508 -- subprogram, which are then used to recheck the default values.
510 function Is_Appropriate_For_Record (T : Entity_Id) return Boolean;
511 -- Prefix is appropriate for record if it is of a record type, or an access
514 function Is_Appropriate_For_Entry_Prefix (T : Entity_Id) return Boolean;
515 -- True if it is of a task type, a protected type, or else an access to one
518 procedure Note_Redundant_Use (Clause : Node_Id);
519 -- Mark the name in a use clause as redundant if the corresponding entity
520 -- is already use-visible. Emit a warning if the use clause comes from
521 -- source and the proper warnings are enabled.
523 procedure Premature_Usage (N : Node_Id);
524 -- Diagnose usage of an entity before it is visible
526 procedure Use_One_Package (P : Entity_Id; N : Node_Id);
527 -- Make visible entities declared in package P potentially use-visible
528 -- in the current context. Also used in the analysis of subunits, when
529 -- re-installing use clauses of parent units. N is the use_clause that
530 -- names P (and possibly other packages).
532 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False);
533 -- Id is the subtype mark from a use type clause. This procedure makes
534 -- the primitive operators of the type potentially use-visible. The
535 -- boolean flag Installed indicates that the clause is being reinstalled
536 -- after previous analysis, and primitive operations are already chained
537 -- on the Used_Operations list of the clause.
539 procedure Write_Info;
540 -- Write debugging information on entities declared in current scope
542 --------------------------------
543 -- Analyze_Exception_Renaming --
544 --------------------------------
546 -- The language only allows a single identifier, but the tree holds an
547 -- identifier list. The parser has already issued an error message if
548 -- there is more than one element in the list.
550 procedure Analyze_Exception_Renaming (N : Node_Id) is
551 Id : constant Node_Id := Defining_Identifier (N);
552 Nam : constant Node_Id := Name (N);
555 Check_SPARK_Restriction ("exception renaming is not allowed", N);
560 Set_Ekind (Id, E_Exception);
561 Set_Exception_Code (Id, Uint_0);
562 Set_Etype (Id, Standard_Exception_Type);
563 Set_Is_Pure (Id, Is_Pure (Current_Scope));
565 if not Is_Entity_Name (Nam) or else
566 Ekind (Entity (Nam)) /= E_Exception
568 Error_Msg_N ("invalid exception name in renaming", Nam);
570 if Present (Renamed_Object (Entity (Nam))) then
571 Set_Renamed_Object (Id, Renamed_Object (Entity (Nam)));
573 Set_Renamed_Object (Id, Entity (Nam));
577 -- Implementation-defined aspect specifications can appear in a renaming
578 -- declaration, but not language-defined ones. The call to procedure
579 -- Analyze_Aspect_Specifications will take care of this error check.
581 if Has_Aspects (N) then
582 Analyze_Aspect_Specifications (N, Id);
584 end Analyze_Exception_Renaming;
586 ---------------------------
587 -- Analyze_Expanded_Name --
588 ---------------------------
590 procedure Analyze_Expanded_Name (N : Node_Id) is
592 -- If the entity pointer is already set, this is an internal node, or a
593 -- node that is analyzed more than once, after a tree modification. In
594 -- such a case there is no resolution to perform, just set the type. For
595 -- completeness, analyze prefix as well.
597 if Present (Entity (N)) then
598 if Is_Type (Entity (N)) then
599 Set_Etype (N, Entity (N));
601 Set_Etype (N, Etype (Entity (N)));
604 Analyze (Prefix (N));
607 Find_Expanded_Name (N);
610 Analyze_Dimension (N);
611 end Analyze_Expanded_Name;
613 ---------------------------------------
614 -- Analyze_Generic_Function_Renaming --
615 ---------------------------------------
617 procedure Analyze_Generic_Function_Renaming (N : Node_Id) is
619 Analyze_Generic_Renaming (N, E_Generic_Function);
620 end Analyze_Generic_Function_Renaming;
622 --------------------------------------
623 -- Analyze_Generic_Package_Renaming --
624 --------------------------------------
626 procedure Analyze_Generic_Package_Renaming (N : Node_Id) is
628 -- Test for the Text_IO special unit case here, since we may be renaming
629 -- one of the subpackages of Text_IO, then join common routine.
631 Check_Text_IO_Special_Unit (Name (N));
633 Analyze_Generic_Renaming (N, E_Generic_Package);
634 end Analyze_Generic_Package_Renaming;
636 ----------------------------------------
637 -- Analyze_Generic_Procedure_Renaming --
638 ----------------------------------------
640 procedure Analyze_Generic_Procedure_Renaming (N : Node_Id) is
642 Analyze_Generic_Renaming (N, E_Generic_Procedure);
643 end Analyze_Generic_Procedure_Renaming;
645 ------------------------------
646 -- Analyze_Generic_Renaming --
647 ------------------------------
649 procedure Analyze_Generic_Renaming
653 New_P : constant Entity_Id := Defining_Entity (N);
655 Inst : Boolean := False; -- prevent junk warning
658 if Name (N) = Error then
662 Check_SPARK_Restriction ("generic renaming is not allowed", N);
664 Generate_Definition (New_P);
666 if Current_Scope /= Standard_Standard then
667 Set_Is_Pure (New_P, Is_Pure (Current_Scope));
670 if Nkind (Name (N)) = N_Selected_Component then
671 Check_Generic_Child_Unit (Name (N), Inst);
676 if not Is_Entity_Name (Name (N)) then
677 Error_Msg_N ("expect entity name in renaming declaration", Name (N));
680 Old_P := Entity (Name (N));
684 Set_Ekind (New_P, K);
686 if Etype (Old_P) = Any_Type then
689 elsif Ekind (Old_P) /= K then
690 Error_Msg_N ("invalid generic unit name", Name (N));
693 if Present (Renamed_Object (Old_P)) then
694 Set_Renamed_Object (New_P, Renamed_Object (Old_P));
696 Set_Renamed_Object (New_P, Old_P);
699 Set_Is_Pure (New_P, Is_Pure (Old_P));
700 Set_Is_Preelaborated (New_P, Is_Preelaborated (Old_P));
702 Set_Etype (New_P, Etype (Old_P));
703 Set_Has_Completion (New_P);
705 if In_Open_Scopes (Old_P) then
706 Error_Msg_N ("within its scope, generic denotes its instance", N);
709 Check_Library_Unit_Renaming (N, Old_P);
712 -- Implementation-defined aspect specifications can appear in a renaming
713 -- declaration, but not language-defined ones. The call to procedure
714 -- Analyze_Aspect_Specifications will take care of this error check.
716 if Has_Aspects (N) then
717 Analyze_Aspect_Specifications (N, New_P);
719 end Analyze_Generic_Renaming;
721 -----------------------------
722 -- Analyze_Object_Renaming --
723 -----------------------------
725 procedure Analyze_Object_Renaming (N : Node_Id) is
726 Loc : constant Source_Ptr := Sloc (N);
727 Id : constant Entity_Id := Defining_Identifier (N);
729 Nam : constant Node_Id := Name (N);
733 procedure Check_Constrained_Object;
734 -- If the nominal type is unconstrained but the renamed object is
735 -- constrained, as can happen with renaming an explicit dereference or
736 -- a function return, build a constrained subtype from the object. If
737 -- the renaming is for a formal in an accept statement, the analysis
738 -- has already established its actual subtype. This is only relevant
739 -- if the renamed object is an explicit dereference.
741 function In_Generic_Scope (E : Entity_Id) return Boolean;
742 -- Determine whether entity E is inside a generic cope
744 ------------------------------
745 -- Check_Constrained_Object --
746 ------------------------------
748 procedure Check_Constrained_Object is
749 Typ : constant Entity_Id := Etype (Nam);
753 if Nkind_In (Nam, N_Function_Call, N_Explicit_Dereference)
754 and then Is_Composite_Type (Etype (Nam))
755 and then not Is_Constrained (Etype (Nam))
756 and then not Has_Unknown_Discriminants (Etype (Nam))
757 and then Expander_Active
759 -- If Actual_Subtype is already set, nothing to do
761 if Ekind_In (Id, E_Variable, E_Constant)
762 and then Present (Actual_Subtype (Id))
766 -- A renaming of an unchecked union has no actual subtype
768 elsif Is_Unchecked_Union (Typ) then
771 -- If a record is limited its size is invariant. This is the case
772 -- in particular with record types with an access discirminant
773 -- that are used in iterators. This is an optimization, but it
774 -- also prevents typing anomalies when the prefix is further
775 -- expanded. Limited types with discriminants are included.
777 elsif Is_Limited_Record (Typ)
779 (Ekind (Typ) = E_Limited_Private_Type
780 and then Has_Discriminants (Typ)
781 and then Is_Access_Type (Etype (First_Discriminant (Typ))))
786 Subt := Make_Temporary (Loc, 'T');
787 Remove_Side_Effects (Nam);
789 Make_Subtype_Declaration (Loc,
790 Defining_Identifier => Subt,
791 Subtype_Indication =>
792 Make_Subtype_From_Expr (Nam, Typ)));
793 Rewrite (Subtype_Mark (N), New_Occurrence_Of (Subt, Loc));
794 Set_Etype (Nam, Subt);
796 -- Freeze subtype at once, to prevent order of elaboration
797 -- issues in the backend. The renamed object exists, so its
798 -- type is already frozen in any case.
800 Freeze_Before (N, Subt);
803 end Check_Constrained_Object;
805 ----------------------
806 -- In_Generic_Scope --
807 ----------------------
809 function In_Generic_Scope (E : Entity_Id) return Boolean is
814 while Present (S) and then S /= Standard_Standard loop
815 if Is_Generic_Unit (S) then
823 end In_Generic_Scope;
825 -- Start of processing for Analyze_Object_Renaming
832 Check_SPARK_Restriction ("object renaming is not allowed", N);
834 Set_Is_Pure (Id, Is_Pure (Current_Scope));
837 -- The renaming of a component that depends on a discriminant requires
838 -- an actual subtype, because in subsequent use of the object Gigi will
839 -- be unable to locate the actual bounds. This explicit step is required
840 -- when the renaming is generated in removing side effects of an
841 -- already-analyzed expression.
843 if Nkind (Nam) = N_Selected_Component and then Analyzed (Nam) then
845 Dec := Build_Actual_Subtype_Of_Component (Etype (Nam), Nam);
847 if Present (Dec) then
848 Insert_Action (N, Dec);
849 T := Defining_Identifier (Dec);
853 -- Complete analysis of the subtype mark in any case, for ASIS use
855 if Present (Subtype_Mark (N)) then
856 Find_Type (Subtype_Mark (N));
859 elsif Present (Subtype_Mark (N)) then
860 Find_Type (Subtype_Mark (N));
861 T := Entity (Subtype_Mark (N));
864 -- Reject renamings of conversions unless the type is tagged, or
865 -- the conversion is implicit (which can occur for cases of anonymous
866 -- access types in Ada 2012).
868 if Nkind (Nam) = N_Type_Conversion
869 and then Comes_From_Source (Nam)
870 and then not Is_Tagged_Type (T)
873 ("renaming of conversion only allowed for tagged types", Nam);
878 -- If the renamed object is a function call of a limited type,
879 -- the expansion of the renaming is complicated by the presence
880 -- of various temporaries and subtypes that capture constraints
881 -- of the renamed object. Rewrite node as an object declaration,
882 -- whose expansion is simpler. Given that the object is limited
883 -- there is no copy involved and no performance hit.
885 if Nkind (Nam) = N_Function_Call
886 and then Is_Limited_View (Etype (Nam))
887 and then not Is_Constrained (Etype (Nam))
888 and then Comes_From_Source (N)
891 Set_Ekind (Id, E_Constant);
893 Make_Object_Declaration (Loc,
894 Defining_Identifier => Id,
895 Constant_Present => True,
896 Object_Definition => New_Occurrence_Of (Etype (Nam), Loc),
897 Expression => Relocate_Node (Nam)));
901 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
902 -- when renaming declaration has a named access type. The Ada 2012
903 -- coverage rules allow an anonymous access type in the context of
904 -- an expected named general access type, but the renaming rules
905 -- require the types to be the same. (An exception is when the type
906 -- of the renaming is also an anonymous access type, which can only
907 -- happen due to a renaming created by the expander.)
909 if Nkind (Nam) = N_Type_Conversion
910 and then not Comes_From_Source (Nam)
911 and then Ekind (Etype (Expression (Nam))) = E_Anonymous_Access_Type
912 and then Ekind (T) /= E_Anonymous_Access_Type
914 Wrong_Type (Expression (Nam), T); -- Should we give better error???
917 -- Check that a class-wide object is not being renamed as an object
918 -- of a specific type. The test for access types is needed to exclude
919 -- cases where the renamed object is a dynamically tagged access
920 -- result, such as occurs in certain expansions.
922 if Is_Tagged_Type (T) then
923 Check_Dynamically_Tagged_Expression
929 -- Ada 2005 (AI-230/AI-254): Access renaming
931 else pragma Assert (Present (Access_Definition (N)));
932 T := Access_Definition
934 N => Access_Definition (N));
938 -- Ada 2005 AI05-105: if the declaration has an anonymous access
939 -- type, the renamed object must also have an anonymous type, and
940 -- this is a name resolution rule. This was implicit in the last part
941 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
944 if not Is_Overloaded (Nam) then
945 if Ekind (Etype (Nam)) /= Ekind (T) then
947 ("expect anonymous access type in object renaming", N);
954 Typ : Entity_Id := Empty;
955 Seen : Boolean := False;
958 Get_First_Interp (Nam, I, It);
959 while Present (It.Typ) loop
961 -- Renaming is ambiguous if more than one candidate
962 -- interpretation is type-conformant with the context.
964 if Ekind (It.Typ) = Ekind (T) then
965 if Ekind (T) = E_Anonymous_Access_Subprogram_Type
968 (Designated_Type (T), Designated_Type (It.Typ))
974 ("ambiguous expression in renaming", Nam);
977 elsif Ekind (T) = E_Anonymous_Access_Type
979 Covers (Designated_Type (T), Designated_Type (It.Typ))
985 ("ambiguous expression in renaming", Nam);
989 if Covers (T, It.Typ) then
991 Set_Etype (Nam, Typ);
992 Set_Is_Overloaded (Nam, False);
996 Get_Next_Interp (I, It);
1003 -- Ada 2005 (AI-231): "In the case where the type is defined by an
1004 -- access_definition, the renamed entity shall be of an access-to-
1005 -- constant type if and only if the access_definition defines an
1006 -- access-to-constant type" ARM 8.5.1(4)
1008 if Constant_Present (Access_Definition (N))
1009 and then not Is_Access_Constant (Etype (Nam))
1011 Error_Msg_N ("(Ada 2005): the renamed object is not "
1012 & "access-to-constant (RM 8.5.1(6))", N);
1014 elsif not Constant_Present (Access_Definition (N))
1015 and then Is_Access_Constant (Etype (Nam))
1017 Error_Msg_N ("(Ada 2005): the renamed object is not "
1018 & "access-to-variable (RM 8.5.1(6))", N);
1021 if Is_Access_Subprogram_Type (Etype (Nam)) then
1022 Check_Subtype_Conformant
1023 (Designated_Type (T), Designated_Type (Etype (Nam)));
1025 elsif not Subtypes_Statically_Match
1026 (Designated_Type (T),
1027 Available_View (Designated_Type (Etype (Nam))))
1030 ("subtype of renamed object does not statically match", N);
1034 -- Special processing for renaming function return object. Some errors
1035 -- and warnings are produced only for calls that come from source.
1037 if Nkind (Nam) = N_Function_Call then
1040 -- Usage is illegal in Ada 83
1043 if Comes_From_Source (Nam) then
1045 ("(Ada 83) cannot rename function return object", Nam);
1048 -- In Ada 95, warn for odd case of renaming parameterless function
1049 -- call if this is not a limited type (where this is useful).
1052 if Warn_On_Object_Renames_Function
1053 and then No (Parameter_Associations (Nam))
1054 and then not Is_Limited_Type (Etype (Nam))
1055 and then Comes_From_Source (Nam)
1058 ("renaming function result object is suspicious?R?", Nam);
1060 ("\function & will be called only once?R?", Nam,
1061 Entity (Name (Nam)));
1062 Error_Msg_N -- CODEFIX
1063 ("\suggest using an initialized constant "
1064 & "object instead?R?", Nam);
1070 Check_Constrained_Object;
1072 -- An object renaming requires an exact match of the type. Class-wide
1073 -- matching is not allowed.
1075 if Is_Class_Wide_Type (T)
1076 and then Base_Type (Etype (Nam)) /= Base_Type (T)
1078 Wrong_Type (Nam, T);
1083 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1085 if Nkind (Nam) = N_Explicit_Dereference
1086 and then Ekind (Etype (T2)) = E_Incomplete_Type
1088 Error_Msg_NE ("invalid use of incomplete type&", Id, T2);
1091 elsif Ekind (Etype (T)) = E_Incomplete_Type then
1092 Error_Msg_NE ("invalid use of incomplete type&", Id, T);
1096 -- Ada 2005 (AI-327)
1098 if Ada_Version >= Ada_2005
1099 and then Nkind (Nam) = N_Attribute_Reference
1100 and then Attribute_Name (Nam) = Name_Priority
1104 elsif Ada_Version >= Ada_2005 and then Nkind (Nam) in N_Has_Entity then
1107 Nam_Ent : Entity_Id;
1110 if Nkind (Nam) = N_Attribute_Reference then
1111 Nam_Ent := Entity (Prefix (Nam));
1113 Nam_Ent := Entity (Nam);
1116 Nam_Decl := Parent (Nam_Ent);
1118 if Has_Null_Exclusion (N)
1119 and then not Has_Null_Exclusion (Nam_Decl)
1121 -- Ada 2005 (AI-423): If the object name denotes a generic
1122 -- formal object of a generic unit G, and the object renaming
1123 -- declaration occurs within the body of G or within the body
1124 -- of a generic unit declared within the declarative region
1125 -- of G, then the declaration of the formal object of G must
1126 -- have a null exclusion or a null-excluding subtype.
1128 if Is_Formal_Object (Nam_Ent)
1129 and then In_Generic_Scope (Id)
1131 if not Can_Never_Be_Null (Etype (Nam_Ent)) then
1133 ("renamed formal does not exclude `NULL` "
1134 & "(RM 8.5.1(4.6/2))", N);
1136 elsif In_Package_Body (Scope (Id)) then
1138 ("formal object does not have a null exclusion"
1139 & "(RM 8.5.1(4.6/2))", N);
1142 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1143 -- shall exclude null.
1145 elsif not Can_Never_Be_Null (Etype (Nam_Ent)) then
1147 ("renamed object does not exclude `NULL` "
1148 & "(RM 8.5.1(4.6/2))", N);
1150 -- An instance is illegal if it contains a renaming that
1151 -- excludes null, and the actual does not. The renaming
1152 -- declaration has already indicated that the declaration
1153 -- of the renamed actual in the instance will raise
1154 -- constraint_error.
1156 elsif Nkind (Nam_Decl) = N_Object_Declaration
1157 and then In_Instance
1159 Present (Corresponding_Generic_Association (Nam_Decl))
1160 and then Nkind (Expression (Nam_Decl)) =
1161 N_Raise_Constraint_Error
1164 ("renamed actual does not exclude `NULL` "
1165 & "(RM 8.5.1(4.6/2))", N);
1167 -- Finally, if there is a null exclusion, the subtype mark
1168 -- must not be null-excluding.
1170 elsif No (Access_Definition (N))
1171 and then Can_Never_Be_Null (T)
1174 ("`NOT NULL` not allowed (& already excludes null)",
1179 elsif Can_Never_Be_Null (T)
1180 and then not Can_Never_Be_Null (Etype (Nam_Ent))
1183 ("renamed object does not exclude `NULL` "
1184 & "(RM 8.5.1(4.6/2))", N);
1186 elsif Has_Null_Exclusion (N)
1187 and then No (Access_Definition (N))
1188 and then Can_Never_Be_Null (T)
1191 ("`NOT NULL` not allowed (& already excludes null)", N, T);
1196 -- Set the Ekind of the entity, unless it has been set already, as is
1197 -- the case for the iteration object over a container with no variable
1198 -- indexing. In that case it's been marked as a constant, and we do not
1199 -- want to change it to a variable.
1201 if Ekind (Id) /= E_Constant then
1202 Set_Ekind (Id, E_Variable);
1205 -- Initialize the object size and alignment. Note that we used to call
1206 -- Init_Size_Align here, but that's wrong for objects which have only
1207 -- an Esize, not an RM_Size field.
1209 Init_Object_Size_Align (Id);
1211 if T = Any_Type or else Etype (Nam) = Any_Type then
1214 -- Verify that the renamed entity is an object or a function call. It
1215 -- may have been rewritten in several ways.
1217 elsif Is_Object_Reference (Nam) then
1218 if Comes_From_Source (N) then
1219 if Is_Dependent_Component_Of_Mutable_Object (Nam) then
1221 ("illegal renaming of discriminant-dependent component", Nam);
1224 -- If the renaming comes from source and the renamed object is a
1225 -- dereference, then mark the prefix as needing debug information,
1226 -- since it might have been rewritten hence internally generated
1227 -- and Debug_Renaming_Declaration will link the renaming to it.
1229 if Nkind (Nam) = N_Explicit_Dereference
1230 and then Is_Entity_Name (Prefix (Nam))
1232 Set_Debug_Info_Needed (Entity (Prefix (Nam)));
1236 -- A static function call may have been folded into a literal
1238 elsif Nkind (Original_Node (Nam)) = N_Function_Call
1240 -- When expansion is disabled, attribute reference is not
1241 -- rewritten as function call. Otherwise it may be rewritten
1242 -- as a conversion, so check original node.
1244 or else (Nkind (Original_Node (Nam)) = N_Attribute_Reference
1245 and then Is_Function_Attribute_Name
1246 (Attribute_Name (Original_Node (Nam))))
1248 -- Weird but legal, equivalent to renaming a function call.
1249 -- Illegal if the literal is the result of constant-folding an
1250 -- attribute reference that is not a function.
1252 or else (Is_Entity_Name (Nam)
1253 and then Ekind (Entity (Nam)) = E_Enumeration_Literal
1255 Nkind (Original_Node (Nam)) /= N_Attribute_Reference)
1257 or else (Nkind (Nam) = N_Type_Conversion
1258 and then Is_Tagged_Type (Entity (Subtype_Mark (Nam))))
1262 elsif Nkind (Nam) = N_Type_Conversion then
1264 ("renaming of conversion only allowed for tagged types", Nam);
1266 -- Ada 2005 (AI-327)
1268 elsif Ada_Version >= Ada_2005
1269 and then Nkind (Nam) = N_Attribute_Reference
1270 and then Attribute_Name (Nam) = Name_Priority
1274 -- Allow internally generated x'Reference expression
1276 elsif Nkind (Nam) = N_Reference then
1280 Error_Msg_N ("expect object name in renaming", Nam);
1285 if not Is_Variable (Nam) then
1286 Set_Ekind (Id, E_Constant);
1287 Set_Never_Set_In_Source (Id, True);
1288 Set_Is_True_Constant (Id, True);
1291 Set_Renamed_Object (Id, Nam);
1293 -- Implementation-defined aspect specifications can appear in a renaming
1294 -- declaration, but not language-defined ones. The call to procedure
1295 -- Analyze_Aspect_Specifications will take care of this error check.
1297 if Has_Aspects (N) then
1298 Analyze_Aspect_Specifications (N, Id);
1301 -- Deal with dimensions
1303 Analyze_Dimension (N);
1304 end Analyze_Object_Renaming;
1306 ------------------------------
1307 -- Analyze_Package_Renaming --
1308 ------------------------------
1310 procedure Analyze_Package_Renaming (N : Node_Id) is
1311 New_P : constant Entity_Id := Defining_Entity (N);
1316 if Name (N) = Error then
1320 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1322 Check_Text_IO_Special_Unit (Name (N));
1324 if Current_Scope /= Standard_Standard then
1325 Set_Is_Pure (New_P, Is_Pure (Current_Scope));
1331 if Is_Entity_Name (Name (N)) then
1332 Old_P := Entity (Name (N));
1337 if Etype (Old_P) = Any_Type then
1338 Error_Msg_N ("expect package name in renaming", Name (N));
1340 elsif Ekind (Old_P) /= E_Package
1341 and then not (Ekind (Old_P) = E_Generic_Package
1342 and then In_Open_Scopes (Old_P))
1344 if Ekind (Old_P) = E_Generic_Package then
1346 ("generic package cannot be renamed as a package", Name (N));
1348 Error_Msg_Sloc := Sloc (Old_P);
1350 ("expect package name in renaming, found& declared#",
1354 -- Set basic attributes to minimize cascaded errors
1356 Set_Ekind (New_P, E_Package);
1357 Set_Etype (New_P, Standard_Void_Type);
1359 -- Here for OK package renaming
1362 -- Entities in the old package are accessible through the renaming
1363 -- entity. The simplest implementation is to have both packages share
1366 Set_Ekind (New_P, E_Package);
1367 Set_Etype (New_P, Standard_Void_Type);
1369 if Present (Renamed_Object (Old_P)) then
1370 Set_Renamed_Object (New_P, Renamed_Object (Old_P));
1372 Set_Renamed_Object (New_P, Old_P);
1375 Set_Has_Completion (New_P);
1377 Set_First_Entity (New_P, First_Entity (Old_P));
1378 Set_Last_Entity (New_P, Last_Entity (Old_P));
1379 Set_First_Private_Entity (New_P, First_Private_Entity (Old_P));
1380 Check_Library_Unit_Renaming (N, Old_P);
1381 Generate_Reference (Old_P, Name (N));
1383 -- If the renaming is in the visible part of a package, then we set
1384 -- Renamed_In_Spec for the renamed package, to prevent giving
1385 -- warnings about no entities referenced. Such a warning would be
1386 -- overenthusiastic, since clients can see entities in the renamed
1387 -- package via the visible package renaming.
1390 Ent : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1392 if Ekind (Ent) = E_Package
1393 and then not In_Private_Part (Ent)
1394 and then In_Extended_Main_Source_Unit (N)
1395 and then Ekind (Old_P) = E_Package
1397 Set_Renamed_In_Spec (Old_P);
1401 -- If this is the renaming declaration of a package instantiation
1402 -- within itself, it is the declaration that ends the list of actuals
1403 -- for the instantiation. At this point, the subtypes that rename
1404 -- the actuals are flagged as generic, to avoid spurious ambiguities
1405 -- if the actuals for two distinct formals happen to coincide. If
1406 -- the actual is a private type, the subtype has a private completion
1407 -- that is flagged in the same fashion.
1409 -- Resolution is identical to what is was in the original generic.
1410 -- On exit from the generic instance, these are turned into regular
1411 -- subtypes again, so they are compatible with types in their class.
1413 if not Is_Generic_Instance (Old_P) then
1416 Spec := Specification (Unit_Declaration_Node (Old_P));
1419 if Nkind (Spec) = N_Package_Specification
1420 and then Present (Generic_Parent (Spec))
1421 and then Old_P = Current_Scope
1422 and then Chars (New_P) = Chars (Generic_Parent (Spec))
1428 E := First_Entity (Old_P);
1429 while Present (E) and then E /= New_P loop
1431 and then Nkind (Parent (E)) = N_Subtype_Declaration
1433 Set_Is_Generic_Actual_Type (E);
1435 if Is_Private_Type (E)
1436 and then Present (Full_View (E))
1438 Set_Is_Generic_Actual_Type (Full_View (E));
1448 -- Implementation-defined aspect specifications can appear in a renaming
1449 -- declaration, but not language-defined ones. The call to procedure
1450 -- Analyze_Aspect_Specifications will take care of this error check.
1452 if Has_Aspects (N) then
1453 Analyze_Aspect_Specifications (N, New_P);
1455 end Analyze_Package_Renaming;
1457 -------------------------------
1458 -- Analyze_Renamed_Character --
1459 -------------------------------
1461 procedure Analyze_Renamed_Character
1466 C : constant Node_Id := Name (N);
1469 if Ekind (New_S) = E_Function then
1470 Resolve (C, Etype (New_S));
1473 Check_Frozen_Renaming (N, New_S);
1477 Error_Msg_N ("character literal can only be renamed as function", N);
1479 end Analyze_Renamed_Character;
1481 ---------------------------------
1482 -- Analyze_Renamed_Dereference --
1483 ---------------------------------
1485 procedure Analyze_Renamed_Dereference
1490 Nam : constant Node_Id := Name (N);
1491 P : constant Node_Id := Prefix (Nam);
1497 if not Is_Overloaded (P) then
1498 if Ekind (Etype (Nam)) /= E_Subprogram_Type
1499 or else not Type_Conformant (Etype (Nam), New_S)
1501 Error_Msg_N ("designated type does not match specification", P);
1510 Get_First_Interp (Nam, Ind, It);
1512 while Present (It.Nam) loop
1514 if Ekind (It.Nam) = E_Subprogram_Type
1515 and then Type_Conformant (It.Nam, New_S)
1517 if Typ /= Any_Id then
1518 Error_Msg_N ("ambiguous renaming", P);
1525 Get_Next_Interp (Ind, It);
1528 if Typ = Any_Type then
1529 Error_Msg_N ("designated type does not match specification", P);
1534 Check_Frozen_Renaming (N, New_S);
1538 end Analyze_Renamed_Dereference;
1540 ---------------------------
1541 -- Analyze_Renamed_Entry --
1542 ---------------------------
1544 procedure Analyze_Renamed_Entry
1549 Nam : constant Node_Id := Name (N);
1550 Sel : constant Node_Id := Selector_Name (Nam);
1551 Is_Actual : constant Boolean := Present (Corresponding_Formal_Spec (N));
1555 if Entity (Sel) = Any_Id then
1557 -- Selector is undefined on prefix. Error emitted already
1559 Set_Has_Completion (New_S);
1563 -- Otherwise find renamed entity and build body of New_S as a call to it
1565 Old_S := Find_Renamed_Entity (N, Selector_Name (Nam), New_S);
1567 if Old_S = Any_Id then
1568 Error_Msg_N (" no subprogram or entry matches specification", N);
1571 Check_Subtype_Conformant (New_S, Old_S, N);
1572 Generate_Reference (New_S, Defining_Entity (N), 'b');
1573 Style.Check_Identifier (Defining_Entity (N), New_S);
1576 -- Only mode conformance required for a renaming_as_declaration
1578 Check_Mode_Conformant (New_S, Old_S, N);
1581 Inherit_Renamed_Profile (New_S, Old_S);
1583 -- The prefix can be an arbitrary expression that yields a task or
1584 -- protected object, so it must be resolved.
1586 Resolve (Prefix (Nam), Scope (Old_S));
1589 Set_Convention (New_S, Convention (Old_S));
1590 Set_Has_Completion (New_S, Inside_A_Generic);
1592 -- AI05-0225: If the renamed entity is a procedure or entry of a
1593 -- protected object, the target object must be a variable.
1595 if Ekind (Scope (Old_S)) in Protected_Kind
1596 and then Ekind (New_S) = E_Procedure
1597 and then not Is_Variable (Prefix (Nam))
1601 ("target object of protected operation used as actual for "
1602 & "formal procedure must be a variable", Nam);
1605 ("target object of protected operation renamed as procedure, "
1606 & "must be a variable", Nam);
1611 Check_Frozen_Renaming (N, New_S);
1613 end Analyze_Renamed_Entry;
1615 -----------------------------------
1616 -- Analyze_Renamed_Family_Member --
1617 -----------------------------------
1619 procedure Analyze_Renamed_Family_Member
1624 Nam : constant Node_Id := Name (N);
1625 P : constant Node_Id := Prefix (Nam);
1629 if (Is_Entity_Name (P) and then Ekind (Entity (P)) = E_Entry_Family)
1630 or else (Nkind (P) = N_Selected_Component
1631 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family)
1633 if Is_Entity_Name (P) then
1634 Old_S := Entity (P);
1636 Old_S := Entity (Selector_Name (P));
1639 if not Entity_Matches_Spec (Old_S, New_S) then
1640 Error_Msg_N ("entry family does not match specification", N);
1643 Check_Subtype_Conformant (New_S, Old_S, N);
1644 Generate_Reference (New_S, Defining_Entity (N), 'b');
1645 Style.Check_Identifier (Defining_Entity (N), New_S);
1649 Error_Msg_N ("no entry family matches specification", N);
1652 Set_Has_Completion (New_S, Inside_A_Generic);
1655 Check_Frozen_Renaming (N, New_S);
1657 end Analyze_Renamed_Family_Member;
1659 -----------------------------------------
1660 -- Analyze_Renamed_Primitive_Operation --
1661 -----------------------------------------
1663 procedure Analyze_Renamed_Primitive_Operation
1672 Ctyp : Conformance_Type) return Boolean;
1673 -- Verify that the signatures of the renamed entity and the new entity
1674 -- match. The first formal of the renamed entity is skipped because it
1675 -- is the target object in any subsequent call.
1683 Ctyp : Conformance_Type) return Boolean
1689 if Ekind (Subp) /= Ekind (New_S) then
1693 Old_F := Next_Formal (First_Formal (Subp));
1694 New_F := First_Formal (New_S);
1695 while Present (Old_F) and then Present (New_F) loop
1696 if not Conforming_Types (Etype (Old_F), Etype (New_F), Ctyp) then
1700 if Ctyp >= Mode_Conformant
1701 and then Ekind (Old_F) /= Ekind (New_F)
1706 Next_Formal (New_F);
1707 Next_Formal (Old_F);
1713 -- Start of processing for Analyze_Renamed_Primitive_Operation
1716 if not Is_Overloaded (Selector_Name (Name (N))) then
1717 Old_S := Entity (Selector_Name (Name (N)));
1719 if not Conforms (Old_S, Type_Conformant) then
1724 -- Find the operation that matches the given signature
1732 Get_First_Interp (Selector_Name (Name (N)), Ind, It);
1734 while Present (It.Nam) loop
1735 if Conforms (It.Nam, Type_Conformant) then
1739 Get_Next_Interp (Ind, It);
1744 if Old_S = Any_Id then
1745 Error_Msg_N (" no subprogram or entry matches specification", N);
1749 if not Conforms (Old_S, Subtype_Conformant) then
1750 Error_Msg_N ("subtype conformance error in renaming", N);
1753 Generate_Reference (New_S, Defining_Entity (N), 'b');
1754 Style.Check_Identifier (Defining_Entity (N), New_S);
1757 -- Only mode conformance required for a renaming_as_declaration
1759 if not Conforms (Old_S, Mode_Conformant) then
1760 Error_Msg_N ("mode conformance error in renaming", N);
1763 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1764 -- view of a subprogram is intrinsic, because the compiler has
1765 -- to generate a wrapper for any call to it. If the name in a
1766 -- subprogram renaming is a prefixed view, the entity is thus
1767 -- intrinsic, and 'Access cannot be applied to it.
1769 Set_Convention (New_S, Convention_Intrinsic);
1772 -- Inherit_Renamed_Profile (New_S, Old_S);
1774 -- The prefix can be an arbitrary expression that yields an
1775 -- object, so it must be resolved.
1777 Resolve (Prefix (Name (N)));
1779 end Analyze_Renamed_Primitive_Operation;
1781 ---------------------------------
1782 -- Analyze_Subprogram_Renaming --
1783 ---------------------------------
1785 procedure Analyze_Subprogram_Renaming (N : Node_Id) is
1786 Formal_Spec : constant Node_Id := Corresponding_Formal_Spec (N);
1787 Is_Actual : constant Boolean := Present (Formal_Spec);
1788 Inst_Node : Node_Id := Empty;
1789 Nam : constant Node_Id := Name (N);
1791 Old_S : Entity_Id := Empty;
1792 Rename_Spec : Entity_Id;
1793 Save_AV : constant Ada_Version_Type := Ada_Version;
1794 Save_AVP : constant Node_Id := Ada_Version_Pragma;
1795 Save_AV_Exp : constant Ada_Version_Type := Ada_Version_Explicit;
1796 Spec : constant Node_Id := Specification (N);
1798 procedure Check_Null_Exclusion
1801 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1802 -- following AI rules:
1804 -- If Ren is a renaming of a formal subprogram and one of its
1805 -- parameters has a null exclusion, then the corresponding formal
1806 -- in Sub must also have one. Otherwise the subtype of the Sub's
1807 -- formal parameter must exclude null.
1809 -- If Ren is a renaming of a formal function and its return
1810 -- profile has a null exclusion, then Sub's return profile must
1811 -- have one. Otherwise the subtype of Sub's return profile must
1814 procedure Freeze_Actual_Profile;
1815 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1816 -- types: a callable entity freezes its profile, unless it has an
1817 -- incomplete untagged formal (RM 13.14(10.2/3)).
1819 function Original_Subprogram (Subp : Entity_Id) return Entity_Id;
1820 -- Find renamed entity when the declaration is a renaming_as_body and
1821 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1822 -- rule that a renaming_as_body is illegal if the declaration occurs
1823 -- before the subprogram it completes is frozen, and renaming indirectly
1824 -- renames the subprogram itself.(Defect Report 8652/0027).
1826 function Check_Class_Wide_Actual return Entity_Id;
1827 -- AI05-0071: In an instance, if the actual for a formal type FT with
1828 -- unknown discriminants is a class-wide type CT, and the generic has
1829 -- a formal subprogram with a box for a primitive operation of FT,
1830 -- then the corresponding actual subprogram denoted by the default is a
1831 -- class-wide operation whose body is a dispatching call. We replace the
1832 -- generated renaming declaration:
1834 -- procedure P (X : CT) renames P;
1836 -- by a different renaming and a class-wide operation:
1838 -- procedure Pr (X : T) renames P; -- renames primitive operation
1839 -- procedure P (X : CT); -- class-wide operation
1841 -- procedure P (X : CT) is begin Pr (X); end; -- dispatching call
1843 -- This rule only applies if there is no explicit visible class-wide
1844 -- operation at the point of the instantiation.
1846 function Has_Class_Wide_Actual return Boolean;
1847 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1848 -- defaulted formal subprogram when the actual for the controlling
1849 -- formal type is class-wide.
1851 -----------------------------
1852 -- Check_Class_Wide_Actual --
1853 -----------------------------
1855 function Check_Class_Wide_Actual return Entity_Id is
1856 Loc : constant Source_Ptr := Sloc (N);
1859 Formal_Type : Entity_Id;
1860 Actual_Type : Entity_Id;
1865 function Make_Call (Prim_Op : Entity_Id) return Node_Id;
1866 -- Build dispatching call for body of class-wide operation
1868 function Make_Spec return Node_Id;
1869 -- Create subprogram specification for declaration and body of
1870 -- class-wide operation, using signature of renaming declaration.
1876 function Make_Call (Prim_Op : Entity_Id) return Node_Id is
1881 Actuals := New_List;
1882 F := First (Parameter_Specifications (Specification (New_Decl)));
1883 while Present (F) loop
1885 Make_Identifier (Loc, Chars (Defining_Identifier (F))));
1889 if Ekind_In (Prim_Op, E_Function, E_Operator) then
1890 return Make_Simple_Return_Statement (Loc,
1892 Make_Function_Call (Loc,
1893 Name => New_Occurrence_Of (Prim_Op, Loc),
1894 Parameter_Associations => Actuals));
1897 Make_Procedure_Call_Statement (Loc,
1898 Name => New_Occurrence_Of (Prim_Op, Loc),
1899 Parameter_Associations => Actuals);
1907 function Make_Spec return Node_Id is
1908 Param_Specs : constant List_Id := Copy_Parameter_List (New_S);
1911 if Ekind (New_S) = E_Procedure then
1913 Make_Procedure_Specification (Loc,
1914 Defining_Unit_Name =>
1915 Make_Defining_Identifier (Loc,
1916 Chars (Defining_Unit_Name (Spec))),
1917 Parameter_Specifications => Param_Specs);
1920 Make_Function_Specification (Loc,
1921 Defining_Unit_Name =>
1922 Make_Defining_Identifier (Loc,
1923 Chars (Defining_Unit_Name (Spec))),
1924 Parameter_Specifications => Param_Specs,
1925 Result_Definition =>
1926 New_Copy_Tree (Result_Definition (Spec)));
1930 -- Start of processing for Check_Class_Wide_Actual
1934 Formal_Type := Empty;
1935 Actual_Type := Empty;
1937 F := First_Formal (Formal_Spec);
1938 while Present (F) loop
1939 if Has_Unknown_Discriminants (Etype (F))
1940 and then not Is_Class_Wide_Type (Etype (F))
1941 and then Is_Class_Wide_Type (Get_Instance_Of (Etype (F)))
1943 Formal_Type := Etype (F);
1944 Actual_Type := Etype (Get_Instance_Of (Formal_Type));
1951 if Present (Formal_Type) then
1953 -- Create declaration and body for class-wide operation
1956 Make_Subprogram_Declaration (Loc, Specification => Make_Spec);
1959 Make_Subprogram_Body (Loc,
1960 Specification => Make_Spec,
1961 Declarations => No_List,
1962 Handled_Statement_Sequence =>
1963 Make_Handled_Sequence_Of_Statements (Loc, New_List));
1965 -- Modify Spec and create internal name for renaming of primitive
1968 Set_Defining_Unit_Name (Spec, Make_Temporary (Loc, 'R'));
1969 F := First (Parameter_Specifications (Spec));
1970 while Present (F) loop
1971 if Nkind (Parameter_Type (F)) = N_Identifier
1972 and then Is_Class_Wide_Type (Entity (Parameter_Type (F)))
1974 Set_Parameter_Type (F, New_Occurrence_Of (Actual_Type, Loc));
1979 New_S := Analyze_Subprogram_Specification (Spec);
1980 Result := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual);
1983 if Result /= Any_Id then
1984 Insert_Before (N, New_Decl);
1987 -- Add dispatching call to body of class-wide operation
1989 Append (Make_Call (Result),
1990 Statements (Handled_Statement_Sequence (New_Body)));
1992 -- The generated body does not freeze. It is analyzed when the
1993 -- generated operation is frozen. This body is only needed if
1994 -- expansion is enabled.
1996 if Expander_Active then
1997 Append_Freeze_Action (Defining_Entity (New_Decl), New_Body);
2000 Result := Defining_Entity (New_Decl);
2003 -- Return the class-wide operation if one was created
2006 end Check_Class_Wide_Actual;
2008 --------------------------
2009 -- Check_Null_Exclusion --
2010 --------------------------
2012 procedure Check_Null_Exclusion
2016 Ren_Formal : Entity_Id;
2017 Sub_Formal : Entity_Id;
2022 Ren_Formal := First_Formal (Ren);
2023 Sub_Formal := First_Formal (Sub);
2024 while Present (Ren_Formal) and then Present (Sub_Formal) loop
2025 if Has_Null_Exclusion (Parent (Ren_Formal))
2027 not (Has_Null_Exclusion (Parent (Sub_Formal))
2028 or else Can_Never_Be_Null (Etype (Sub_Formal)))
2031 ("`NOT NULL` required for parameter &",
2032 Parent (Sub_Formal), Sub_Formal);
2035 Next_Formal (Ren_Formal);
2036 Next_Formal (Sub_Formal);
2039 -- Return profile check
2041 if Nkind (Parent (Ren)) = N_Function_Specification
2042 and then Nkind (Parent (Sub)) = N_Function_Specification
2043 and then Has_Null_Exclusion (Parent (Ren))
2044 and then not (Has_Null_Exclusion (Parent (Sub))
2045 or else Can_Never_Be_Null (Etype (Sub)))
2048 ("return must specify `NOT NULL`",
2049 Result_Definition (Parent (Sub)));
2051 end Check_Null_Exclusion;
2053 ---------------------------
2054 -- Freeze_Actual_Profile --
2055 ---------------------------
2057 procedure Freeze_Actual_Profile is
2059 Has_Untagged_Inc : Boolean;
2060 Instantiation_Node : constant Node_Id := Parent (N);
2063 if Ada_Version >= Ada_2012 then
2064 F := First_Formal (Formal_Spec);
2065 Has_Untagged_Inc := False;
2066 while Present (F) loop
2067 if Ekind (Etype (F)) = E_Incomplete_Type
2068 and then not Is_Tagged_Type (Etype (F))
2070 Has_Untagged_Inc := True;
2074 F := Next_Formal (F);
2077 if Ekind (Formal_Spec) = E_Function
2078 and then Ekind (Etype (Formal_Spec)) = E_Incomplete_Type
2079 and then not Is_Tagged_Type (Etype (F))
2081 Has_Untagged_Inc := True;
2084 if not Has_Untagged_Inc then
2085 F := First_Formal (Old_S);
2086 while Present (F) loop
2087 Freeze_Before (Instantiation_Node, Etype (F));
2089 if Is_Incomplete_Or_Private_Type (Etype (F))
2090 and then No (Underlying_Type (Etype (F)))
2093 -- Exclude generic types, or types derived from them.
2094 -- They will be frozen in the enclosing instance.
2096 if Is_Generic_Type (Etype (F))
2097 or else Is_Generic_Type (Root_Type (Etype (F)))
2102 ("type& must be frozen before this point",
2103 Instantiation_Node, Etype (F));
2107 F := Next_Formal (F);
2111 end Freeze_Actual_Profile;
2113 ---------------------------
2114 -- Has_Class_Wide_Actual --
2115 ---------------------------
2117 function Has_Class_Wide_Actual return Boolean is
2123 and then Nkind (Nam) in N_Has_Entity
2124 and then Present (Entity (Nam))
2125 and then Is_Dispatching_Operation (Entity (Nam))
2127 F_Nam := First_Entity (Entity (Nam));
2128 F_Spec := First_Formal (Formal_Spec);
2129 while Present (F_Nam) and then Present (F_Spec) loop
2130 if Is_Controlling_Formal (F_Nam)
2131 and then Has_Unknown_Discriminants (Etype (F_Spec))
2132 and then not Is_Class_Wide_Type (Etype (F_Spec))
2133 and then Is_Class_Wide_Type (Get_Instance_Of (Etype (F_Spec)))
2138 Next_Entity (F_Nam);
2139 Next_Formal (F_Spec);
2144 end Has_Class_Wide_Actual;
2146 -------------------------
2147 -- Original_Subprogram --
2148 -------------------------
2150 function Original_Subprogram (Subp : Entity_Id) return Entity_Id is
2151 Orig_Decl : Node_Id;
2152 Orig_Subp : Entity_Id;
2155 -- First case: renamed entity is itself a renaming
2157 if Present (Alias (Subp)) then
2158 return Alias (Subp);
2160 elsif Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Declaration
2161 and then Present (Corresponding_Body (Unit_Declaration_Node (Subp)))
2163 -- Check if renamed entity is a renaming_as_body
2166 Unit_Declaration_Node
2167 (Corresponding_Body (Unit_Declaration_Node (Subp)));
2169 if Nkind (Orig_Decl) = N_Subprogram_Renaming_Declaration then
2170 Orig_Subp := Entity (Name (Orig_Decl));
2172 if Orig_Subp = Rename_Spec then
2174 -- Circularity detected
2179 return (Original_Subprogram (Orig_Subp));
2187 end Original_Subprogram;
2189 CW_Actual : constant Boolean := Has_Class_Wide_Actual;
2190 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2191 -- defaulted formal subprogram when the actual for a related formal
2192 -- type is class-wide.
2194 -- Start of processing for Analyze_Subprogram_Renaming
2197 -- We must test for the attribute renaming case before the Analyze
2198 -- call because otherwise Sem_Attr will complain that the attribute
2199 -- is missing an argument when it is analyzed.
2201 if Nkind (Nam) = N_Attribute_Reference then
2203 -- In the case of an abstract formal subprogram association, rewrite
2204 -- an actual given by a stream attribute as the name of the
2205 -- corresponding stream primitive of the type.
2207 -- In a generic context the stream operations are not generated, and
2208 -- this must be treated as a normal attribute reference, to be
2209 -- expanded in subsequent instantiations.
2212 and then Is_Abstract_Subprogram (Formal_Spec)
2213 and then Expander_Active
2216 Stream_Prim : Entity_Id;
2217 Prefix_Type : constant Entity_Id := Entity (Prefix (Nam));
2220 -- The class-wide forms of the stream attributes are not
2221 -- primitive dispatching operations (even though they
2222 -- internally dispatch to a stream attribute).
2224 if Is_Class_Wide_Type (Prefix_Type) then
2226 ("attribute must be a primitive dispatching operation",
2231 -- Retrieve the primitive subprogram associated with the
2232 -- attribute. This can only be a stream attribute, since those
2233 -- are the only ones that are dispatching (and the actual for
2234 -- an abstract formal subprogram must be dispatching
2238 case Attribute_Name (Nam) is
2241 Find_Prim_Op (Prefix_Type, TSS_Stream_Input);
2244 Find_Prim_Op (Prefix_Type, TSS_Stream_Output);
2247 Find_Prim_Op (Prefix_Type, TSS_Stream_Read);
2250 Find_Prim_Op (Prefix_Type, TSS_Stream_Write);
2253 ("attribute must be a primitive"
2254 & " dispatching operation", Nam);
2260 -- If no operation was found, and the type is limited,
2261 -- the user should have defined one.
2263 when Program_Error =>
2264 if Is_Limited_Type (Prefix_Type) then
2266 ("stream operation not defined for type&",
2270 -- Otherwise, compiler should have generated default
2277 -- Rewrite the attribute into the name of its corresponding
2278 -- primitive dispatching subprogram. We can then proceed with
2279 -- the usual processing for subprogram renamings.
2282 Prim_Name : constant Node_Id :=
2283 Make_Identifier (Sloc (Nam),
2284 Chars => Chars (Stream_Prim));
2286 Set_Entity (Prim_Name, Stream_Prim);
2287 Rewrite (Nam, Prim_Name);
2292 -- Normal processing for a renaming of an attribute
2295 Attribute_Renaming (N);
2300 -- Check whether this declaration corresponds to the instantiation
2301 -- of a formal subprogram.
2303 -- If this is an instantiation, the corresponding actual is frozen and
2304 -- error messages can be made more precise. If this is a default
2305 -- subprogram, the entity is already established in the generic, and is
2306 -- not retrieved by visibility. If it is a default with a box, the
2307 -- candidate interpretations, if any, have been collected when building
2308 -- the renaming declaration. If overloaded, the proper interpretation is
2309 -- determined in Find_Renamed_Entity. If the entity is an operator,
2310 -- Find_Renamed_Entity applies additional visibility checks.
2313 Inst_Node := Unit_Declaration_Node (Formal_Spec);
2315 -- Check whether the renaming is for a defaulted actual subprogram
2316 -- with a class-wide actual.
2319 New_S := Analyze_Subprogram_Specification (Spec);
2320 Old_S := Check_Class_Wide_Actual;
2322 elsif Is_Entity_Name (Nam)
2323 and then Present (Entity (Nam))
2324 and then not Comes_From_Source (Nam)
2325 and then not Is_Overloaded (Nam)
2327 Old_S := Entity (Nam);
2328 New_S := Analyze_Subprogram_Specification (Spec);
2332 if Ekind (Entity (Nam)) = E_Operator then
2336 if Box_Present (Inst_Node) then
2337 Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual);
2339 -- If there is an immediately visible homonym of the operator
2340 -- and the declaration has a default, this is worth a warning
2341 -- because the user probably did not intend to get the pre-
2342 -- defined operator, visible in the generic declaration. To
2343 -- find if there is an intended candidate, analyze the renaming
2344 -- again in the current context.
2346 elsif Scope (Old_S) = Standard_Standard
2347 and then Present (Default_Name (Inst_Node))
2350 Decl : constant Node_Id := New_Copy_Tree (N);
2354 Set_Entity (Name (Decl), Empty);
2355 Analyze (Name (Decl));
2357 Find_Renamed_Entity (Decl, Name (Decl), New_S, True);
2360 and then In_Open_Scopes (Scope (Hidden))
2361 and then Is_Immediately_Visible (Hidden)
2362 and then Comes_From_Source (Hidden)
2363 and then Hidden /= Old_S
2365 Error_Msg_Sloc := Sloc (Hidden);
2366 Error_Msg_N ("default subprogram is resolved " &
2367 "in the generic declaration " &
2368 "(RM 12.6(17))??", N);
2369 Error_Msg_NE ("\and will not use & #??", N, Hidden);
2377 New_S := Analyze_Subprogram_Specification (Spec);
2381 -- Renamed entity must be analyzed first, to avoid being hidden by
2382 -- new name (which might be the same in a generic instance).
2386 -- The renaming defines a new overloaded entity, which is analyzed
2387 -- like a subprogram declaration.
2389 New_S := Analyze_Subprogram_Specification (Spec);
2392 if Current_Scope /= Standard_Standard then
2393 Set_Is_Pure (New_S, Is_Pure (Current_Scope));
2396 -- Set SPARK mode from current context
2398 Set_SPARK_Pragma (New_S, SPARK_Mode_Pragma);
2399 Set_SPARK_Pragma_Inherited (New_S, True);
2401 Rename_Spec := Find_Corresponding_Spec (N);
2403 -- Case of Renaming_As_Body
2405 if Present (Rename_Spec) then
2407 -- Renaming declaration is the completion of the declaration of
2408 -- Rename_Spec. We build an actual body for it at the freezing point.
2410 Set_Corresponding_Spec (N, Rename_Spec);
2412 -- Deal with special case of stream functions of abstract types
2415 if Nkind (Unit_Declaration_Node (Rename_Spec)) =
2416 N_Abstract_Subprogram_Declaration
2418 -- Input stream functions are abstract if the object type is
2419 -- abstract. Similarly, all default stream functions for an
2420 -- interface type are abstract. However, these subprograms may
2421 -- receive explicit declarations in representation clauses, making
2422 -- the attribute subprograms usable as defaults in subsequent
2424 -- In this case we rewrite the declaration to make the subprogram
2425 -- non-abstract. We remove the previous declaration, and insert
2426 -- the new one at the point of the renaming, to prevent premature
2427 -- access to unfrozen types. The new declaration reuses the
2428 -- specification of the previous one, and must not be analyzed.
2431 (Is_Primitive (Entity (Nam))
2433 Is_Abstract_Type (Find_Dispatching_Type (Entity (Nam))));
2435 Old_Decl : constant Node_Id :=
2436 Unit_Declaration_Node (Rename_Spec);
2437 New_Decl : constant Node_Id :=
2438 Make_Subprogram_Declaration (Sloc (N),
2440 Relocate_Node (Specification (Old_Decl)));
2443 Insert_After (N, New_Decl);
2444 Set_Is_Abstract_Subprogram (Rename_Spec, False);
2445 Set_Analyzed (New_Decl);
2449 Set_Corresponding_Body (Unit_Declaration_Node (Rename_Spec), New_S);
2451 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2452 Error_Msg_N ("(Ada 83) renaming cannot serve as a body", N);
2455 Set_Convention (New_S, Convention (Rename_Spec));
2456 Check_Fully_Conformant (New_S, Rename_Spec);
2457 Set_Public_Status (New_S);
2459 -- The specification does not introduce new formals, but only
2460 -- repeats the formals of the original subprogram declaration.
2461 -- For cross-reference purposes, and for refactoring tools, we
2462 -- treat the formals of the renaming declaration as body formals.
2464 Reference_Body_Formals (Rename_Spec, New_S);
2466 -- Indicate that the entity in the declaration functions like the
2467 -- corresponding body, and is not a new entity. The body will be
2468 -- constructed later at the freeze point, so indicate that the
2469 -- completion has not been seen yet.
2471 Set_Contract (New_S, Empty);
2472 Set_Ekind (New_S, E_Subprogram_Body);
2473 New_S := Rename_Spec;
2474 Set_Has_Completion (Rename_Spec, False);
2476 -- Ada 2005: check overriding indicator
2478 if Present (Overridden_Operation (Rename_Spec)) then
2479 if Must_Not_Override (Specification (N)) then
2481 ("subprogram& overrides inherited operation",
2484 Style_Check and then not Must_Override (Specification (N))
2486 Style.Missing_Overriding (N, Rename_Spec);
2489 elsif Must_Override (Specification (N)) then
2490 Error_Msg_NE ("subprogram& is not overriding", N, Rename_Spec);
2493 -- Normal subprogram renaming (not renaming as body)
2496 Generate_Definition (New_S);
2497 New_Overloaded_Entity (New_S);
2499 if Is_Entity_Name (Nam)
2500 and then Is_Intrinsic_Subprogram (Entity (Nam))
2504 Check_Delayed_Subprogram (New_S);
2508 -- There is no need for elaboration checks on the new entity, which may
2509 -- be called before the next freezing point where the body will appear.
2510 -- Elaboration checks refer to the real entity, not the one created by
2511 -- the renaming declaration.
2513 Set_Kill_Elaboration_Checks (New_S, True);
2515 -- If we had a previous error, indicate a completely is present to stop
2516 -- junk cascaded messages, but don't take any further action.
2518 if Etype (Nam) = Any_Type then
2519 Set_Has_Completion (New_S);
2522 -- Case where name has the form of a selected component
2524 elsif Nkind (Nam) = N_Selected_Component then
2526 -- A name which has the form A.B can designate an entry of task A, a
2527 -- protected operation of protected object A, or finally a primitive
2528 -- operation of object A. In the later case, A is an object of some
2529 -- tagged type, or an access type that denotes one such. To further
2530 -- distinguish these cases, note that the scope of a task entry or
2531 -- protected operation is type of the prefix.
2533 -- The prefix could be an overloaded function call that returns both
2534 -- kinds of operations. This overloading pathology is left to the
2535 -- dedicated reader ???
2538 T : constant Entity_Id := Etype (Prefix (Nam));
2546 and then Is_Tagged_Type (Designated_Type (T))))
2547 and then Scope (Entity (Selector_Name (Nam))) /= T
2549 Analyze_Renamed_Primitive_Operation
2550 (N, New_S, Present (Rename_Spec));
2554 -- Renamed entity is an entry or protected operation. For those
2555 -- cases an explicit body is built (at the point of freezing of
2556 -- this entity) that contains a call to the renamed entity.
2558 -- This is not allowed for renaming as body if the renamed
2559 -- spec is already frozen (see RM 8.5.4(5) for details).
2561 if Present (Rename_Spec) and then Is_Frozen (Rename_Spec) then
2563 ("renaming-as-body cannot rename entry as subprogram", N);
2565 ("\since & is already frozen (RM 8.5.4(5))",
2568 Analyze_Renamed_Entry (N, New_S, Present (Rename_Spec));
2575 -- Case where name is an explicit dereference X.all
2577 elsif Nkind (Nam) = N_Explicit_Dereference then
2579 -- Renamed entity is designated by access_to_subprogram expression.
2580 -- Must build body to encapsulate call, as in the entry case.
2582 Analyze_Renamed_Dereference (N, New_S, Present (Rename_Spec));
2585 -- Indexed component
2587 elsif Nkind (Nam) = N_Indexed_Component then
2588 Analyze_Renamed_Family_Member (N, New_S, Present (Rename_Spec));
2591 -- Character literal
2593 elsif Nkind (Nam) = N_Character_Literal then
2594 Analyze_Renamed_Character (N, New_S, Present (Rename_Spec));
2597 -- Only remaining case is where we have a non-entity name, or a
2598 -- renaming of some other non-overloadable entity.
2600 elsif not Is_Entity_Name (Nam)
2601 or else not Is_Overloadable (Entity (Nam))
2603 -- Do not mention the renaming if it comes from an instance
2605 if not Is_Actual then
2606 Error_Msg_N ("expect valid subprogram name in renaming", N);
2608 Error_Msg_NE ("no visible subprogram for formal&", N, Nam);
2614 -- Find the renamed entity that matches the given specification. Disable
2615 -- Ada_83 because there is no requirement of full conformance between
2616 -- renamed entity and new entity, even though the same circuit is used.
2618 -- This is a bit of an odd case, which introduces a really irregular use
2619 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
2622 Ada_Version := Ada_Version_Type'Max (Ada_Version, Ada_95);
2623 Ada_Version_Pragma := Empty;
2624 Ada_Version_Explicit := Ada_Version;
2627 Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual);
2629 -- The visible operation may be an inherited abstract operation that
2630 -- was overridden in the private part, in which case a call will
2631 -- dispatch to the overriding operation. Use the overriding one in
2632 -- the renaming declaration, to prevent spurious errors below.
2634 if Is_Overloadable (Old_S)
2635 and then Is_Abstract_Subprogram (Old_S)
2636 and then No (DTC_Entity (Old_S))
2637 and then Present (Alias (Old_S))
2638 and then not Is_Abstract_Subprogram (Alias (Old_S))
2639 and then Present (Overridden_Operation (Alias (Old_S)))
2641 Old_S := Alias (Old_S);
2644 -- When the renamed subprogram is overloaded and used as an actual
2645 -- of a generic, its entity is set to the first available homonym.
2646 -- We must first disambiguate the name, then set the proper entity.
2648 if Is_Actual and then Is_Overloaded (Nam) then
2649 Set_Entity (Nam, Old_S);
2653 -- Most common case: subprogram renames subprogram. No body is generated
2654 -- in this case, so we must indicate the declaration is complete as is.
2655 -- and inherit various attributes of the renamed subprogram.
2657 if No (Rename_Spec) then
2658 Set_Has_Completion (New_S);
2659 Set_Is_Imported (New_S, Is_Imported (Entity (Nam)));
2660 Set_Is_Pure (New_S, Is_Pure (Entity (Nam)));
2661 Set_Is_Preelaborated (New_S, Is_Preelaborated (Entity (Nam)));
2663 -- Ada 2005 (AI-423): Check the consistency of null exclusions
2664 -- between a subprogram and its correct renaming.
2666 -- Note: the Any_Id check is a guard that prevents compiler crashes
2667 -- when performing a null exclusion check between a renaming and a
2668 -- renamed subprogram that has been found to be illegal.
2670 if Ada_Version >= Ada_2005 and then Entity (Nam) /= Any_Id then
2671 Check_Null_Exclusion
2673 Sub => Entity (Nam));
2676 -- Enforce the Ada 2005 rule that the renamed entity cannot require
2677 -- overriding. The flag Requires_Overriding is set very selectively
2678 -- and misses some other illegal cases. The additional conditions
2679 -- checked below are sufficient but not necessary ???
2681 -- The rule does not apply to the renaming generated for an actual
2682 -- subprogram in an instance.
2687 -- Guard against previous errors, and omit renamings of predefined
2690 elsif not Ekind_In (Old_S, E_Function, E_Procedure) then
2693 elsif Requires_Overriding (Old_S)
2695 (Is_Abstract_Subprogram (Old_S)
2696 and then Present (Find_Dispatching_Type (Old_S))
2698 not Is_Abstract_Type (Find_Dispatching_Type (Old_S)))
2701 ("renamed entity cannot be "
2702 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N);
2706 if Old_S /= Any_Id then
2707 if Is_Actual and then From_Default (N) then
2709 -- This is an implicit reference to the default actual
2711 Generate_Reference (Old_S, Nam, Typ => 'i', Force => True);
2714 Generate_Reference (Old_S, Nam);
2717 Check_Internal_Protected_Use (N, Old_S);
2719 -- For a renaming-as-body, require subtype conformance, but if the
2720 -- declaration being completed has not been frozen, then inherit the
2721 -- convention of the renamed subprogram prior to checking conformance
2722 -- (unless the renaming has an explicit convention established; the
2723 -- rule stated in the RM doesn't seem to address this ???).
2725 if Present (Rename_Spec) then
2726 Generate_Reference (Rename_Spec, Defining_Entity (Spec), 'b');
2727 Style.Check_Identifier (Defining_Entity (Spec), Rename_Spec);
2729 if not Is_Frozen (Rename_Spec) then
2730 if not Has_Convention_Pragma (Rename_Spec) then
2731 Set_Convention (New_S, Convention (Old_S));
2734 if Ekind (Old_S) /= E_Operator then
2735 Check_Mode_Conformant (New_S, Old_S, Spec);
2738 if Original_Subprogram (Old_S) = Rename_Spec then
2739 Error_Msg_N ("unfrozen subprogram cannot rename itself ", N);
2742 Check_Subtype_Conformant (New_S, Old_S, Spec);
2745 Check_Frozen_Renaming (N, Rename_Spec);
2747 -- Check explicitly that renamed entity is not intrinsic, because
2748 -- in a generic the renamed body is not built. In this case,
2749 -- the renaming_as_body is a completion.
2751 if Inside_A_Generic then
2752 if Is_Frozen (Rename_Spec)
2753 and then Is_Intrinsic_Subprogram (Old_S)
2756 ("subprogram in renaming_as_body cannot be intrinsic",
2760 Set_Has_Completion (Rename_Spec);
2763 elsif Ekind (Old_S) /= E_Operator then
2765 -- If this a defaulted subprogram for a class-wide actual there is
2766 -- no check for mode conformance, given that the signatures don't
2767 -- match (the source mentions T but the actual mentions T'Class).
2771 elsif not Is_Actual or else No (Enclosing_Instance) then
2772 Check_Mode_Conformant (New_S, Old_S);
2775 if Is_Actual and then Error_Posted (New_S) then
2776 Error_Msg_NE ("invalid actual subprogram: & #!", N, Old_S);
2780 if No (Rename_Spec) then
2782 -- The parameter profile of the new entity is that of the renamed
2783 -- entity: the subtypes given in the specification are irrelevant.
2785 Inherit_Renamed_Profile (New_S, Old_S);
2787 -- A call to the subprogram is transformed into a call to the
2788 -- renamed entity. This is transitive if the renamed entity is
2789 -- itself a renaming.
2791 if Present (Alias (Old_S)) then
2792 Set_Alias (New_S, Alias (Old_S));
2794 Set_Alias (New_S, Old_S);
2797 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
2798 -- renaming as body, since the entity in this case is not an
2799 -- intrinsic (it calls an intrinsic, but we have a real body for
2800 -- this call, and it is in this body that the required intrinsic
2801 -- processing will take place).
2803 -- Also, if this is a renaming of inequality, the renamed operator
2804 -- is intrinsic, but what matters is the corresponding equality
2805 -- operator, which may be user-defined.
2807 Set_Is_Intrinsic_Subprogram
2809 Is_Intrinsic_Subprogram (Old_S)
2811 (Chars (Old_S) /= Name_Op_Ne
2812 or else Ekind (Old_S) = E_Operator
2813 or else Is_Intrinsic_Subprogram
2814 (Corresponding_Equality (Old_S))));
2816 if Ekind (Alias (New_S)) = E_Operator then
2817 Set_Has_Delayed_Freeze (New_S, False);
2820 -- If the renaming corresponds to an association for an abstract
2821 -- formal subprogram, then various attributes must be set to
2822 -- indicate that the renaming is an abstract dispatching operation
2823 -- with a controlling type.
2825 if Is_Actual and then Is_Abstract_Subprogram (Formal_Spec) then
2827 -- Mark the renaming as abstract here, so Find_Dispatching_Type
2828 -- see it as corresponding to a generic association for a
2829 -- formal abstract subprogram
2831 Set_Is_Abstract_Subprogram (New_S);
2834 New_S_Ctrl_Type : constant Entity_Id :=
2835 Find_Dispatching_Type (New_S);
2836 Old_S_Ctrl_Type : constant Entity_Id :=
2837 Find_Dispatching_Type (Old_S);
2840 if Old_S_Ctrl_Type /= New_S_Ctrl_Type then
2842 ("actual must be dispatching subprogram for type&",
2843 Nam, New_S_Ctrl_Type);
2846 Set_Is_Dispatching_Operation (New_S);
2847 Check_Controlling_Formals (New_S_Ctrl_Type, New_S);
2849 -- If the actual in the formal subprogram is itself a
2850 -- formal abstract subprogram association, there's no
2851 -- dispatch table component or position to inherit.
2853 if Present (DTC_Entity (Old_S)) then
2854 Set_DTC_Entity (New_S, DTC_Entity (Old_S));
2855 Set_DT_Position (New_S, DT_Position (Old_S));
2865 -- The following is illegal, because F hides whatever other F may
2867 -- function F (...) renames F;
2870 or else (Nkind (Nam) /= N_Expanded_Name
2871 and then Chars (Old_S) = Chars (New_S))
2873 Error_Msg_N ("subprogram cannot rename itself", N);
2875 -- This is illegal even if we use a selector:
2876 -- function F (...) renames Pkg.F;
2877 -- because F is still hidden.
2879 elsif Nkind (Nam) = N_Expanded_Name
2880 and then Entity (Prefix (Nam)) = Current_Scope
2881 and then Chars (Selector_Name (Nam)) = Chars (New_S)
2883 -- This is an error, but we overlook the error and accept the
2884 -- renaming if the special Overriding_Renamings mode is in effect.
2886 if not Overriding_Renamings then
2888 ("implicit operation& is not visible (RM 8.3 (15))",
2893 Set_Convention (New_S, Convention (Old_S));
2895 if Is_Abstract_Subprogram (Old_S) then
2896 if Present (Rename_Spec) then
2898 ("a renaming-as-body cannot rename an abstract subprogram",
2900 Set_Has_Completion (Rename_Spec);
2902 Set_Is_Abstract_Subprogram (New_S);
2906 Check_Library_Unit_Renaming (N, Old_S);
2908 -- Pathological case: procedure renames entry in the scope of its
2909 -- task. Entry is given by simple name, but body must be built for
2910 -- procedure. Of course if called it will deadlock.
2912 if Ekind (Old_S) = E_Entry then
2913 Set_Has_Completion (New_S, False);
2914 Set_Alias (New_S, Empty);
2918 Freeze_Before (N, Old_S);
2919 Freeze_Actual_Profile;
2920 Set_Has_Delayed_Freeze (New_S, False);
2921 Freeze_Before (N, New_S);
2923 -- An abstract subprogram is only allowed as an actual in the case
2924 -- where the formal subprogram is also abstract.
2926 if (Ekind (Old_S) = E_Procedure or else Ekind (Old_S) = E_Function)
2927 and then Is_Abstract_Subprogram (Old_S)
2928 and then not Is_Abstract_Subprogram (Formal_Spec)
2931 ("abstract subprogram not allowed as generic actual", Nam);
2936 -- A common error is to assume that implicit operators for types are
2937 -- defined in Standard, or in the scope of a subtype. In those cases
2938 -- where the renamed entity is given with an expanded name, it is
2939 -- worth mentioning that operators for the type are not declared in
2940 -- the scope given by the prefix.
2942 if Nkind (Nam) = N_Expanded_Name
2943 and then Nkind (Selector_Name (Nam)) = N_Operator_Symbol
2944 and then Scope (Entity (Nam)) = Standard_Standard
2947 T : constant Entity_Id :=
2948 Base_Type (Etype (First_Formal (New_S)));
2950 Error_Msg_Node_2 := Prefix (Nam);
2952 ("operator for type& is not declared in&", Prefix (Nam), T);
2957 ("no visible subprogram matches the specification for&",
2961 if Present (Candidate_Renaming) then
2968 F1 := First_Formal (Candidate_Renaming);
2969 F2 := First_Formal (New_S);
2970 T1 := First_Subtype (Etype (F1));
2971 while Present (F1) and then Present (F2) loop
2976 if Present (F1) and then Present (Default_Value (F1)) then
2977 if Present (Next_Formal (F1)) then
2979 ("\missing specification for &" &
2980 " and other formals with defaults", Spec, F1);
2983 ("\missing specification for &", Spec, F1);
2987 if Nkind (Nam) = N_Operator_Symbol
2988 and then From_Default (N)
2990 Error_Msg_Node_2 := T1;
2992 ("default & on & is not directly visible",
2999 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3000 -- controlling access parameters are known non-null for the renamed
3001 -- subprogram. Test also applies to a subprogram instantiation that
3002 -- is dispatching. Test is skipped if some previous error was detected
3003 -- that set Old_S to Any_Id.
3005 if Ada_Version >= Ada_2005
3006 and then Old_S /= Any_Id
3007 and then not Is_Dispatching_Operation (Old_S)
3008 and then Is_Dispatching_Operation (New_S)
3015 Old_F := First_Formal (Old_S);
3016 New_F := First_Formal (New_S);
3017 while Present (Old_F) loop
3018 if Ekind (Etype (Old_F)) = E_Anonymous_Access_Type
3019 and then Is_Controlling_Formal (New_F)
3020 and then not Can_Never_Be_Null (Old_F)
3022 Error_Msg_N ("access parameter is controlling,", New_F);
3024 ("\corresponding parameter of& "
3025 & "must be explicitly null excluding", New_F, Old_S);
3028 Next_Formal (Old_F);
3029 Next_Formal (New_F);
3034 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3035 -- is to warn if an operator is being renamed as a different operator.
3036 -- If the operator is predefined, examine the kind of the entity, not
3037 -- the abbreviated declaration in Standard.
3039 if Comes_From_Source (N)
3040 and then Present (Old_S)
3041 and then (Nkind (Old_S) = N_Defining_Operator_Symbol
3042 or else Ekind (Old_S) = E_Operator)
3043 and then Nkind (New_S) = N_Defining_Operator_Symbol
3044 and then Chars (Old_S) /= Chars (New_S)
3047 ("& is being renamed as a different operator??", N, Old_S);
3050 -- Check for renaming of obsolescent subprogram
3052 Check_Obsolescent_2005_Entity (Entity (Nam), Nam);
3054 -- Another warning or some utility: if the new subprogram as the same
3055 -- name as the old one, the old one is not hidden by an outer homograph,
3056 -- the new one is not a public symbol, and the old one is otherwise
3057 -- directly visible, the renaming is superfluous.
3059 if Chars (Old_S) = Chars (New_S)
3060 and then Comes_From_Source (N)
3061 and then Scope (Old_S) /= Standard_Standard
3062 and then Warn_On_Redundant_Constructs
3063 and then (Is_Immediately_Visible (Old_S)
3064 or else Is_Potentially_Use_Visible (Old_S))
3065 and then Is_Overloadable (Current_Scope)
3066 and then Chars (Current_Scope) /= Chars (Old_S)
3069 ("redundant renaming, entity is directly visible?r?", Name (N));
3072 -- Implementation-defined aspect specifications can appear in a renaming
3073 -- declaration, but not language-defined ones. The call to procedure
3074 -- Analyze_Aspect_Specifications will take care of this error check.
3076 if Has_Aspects (N) then
3077 Analyze_Aspect_Specifications (N, New_S);
3080 Ada_Version := Save_AV;
3081 Ada_Version_Pragma := Save_AVP;
3082 Ada_Version_Explicit := Save_AV_Exp;
3083 end Analyze_Subprogram_Renaming;
3085 -------------------------
3086 -- Analyze_Use_Package --
3087 -------------------------
3089 -- Resolve the package names in the use clause, and make all the visible
3090 -- entities defined in the package potentially use-visible. If the package
3091 -- is already in use from a previous use clause, its visible entities are
3092 -- already use-visible. In that case, mark the occurrence as a redundant
3093 -- use. If the package is an open scope, i.e. if the use clause occurs
3094 -- within the package itself, ignore it.
3096 procedure Analyze_Use_Package (N : Node_Id) is
3097 Pack_Name : Node_Id;
3100 -- Start of processing for Analyze_Use_Package
3103 Check_SPARK_Restriction ("use clause is not allowed", N);
3105 Set_Hidden_By_Use_Clause (N, No_Elist);
3107 -- Use clause not allowed in a spec of a predefined package declaration
3108 -- except that packages whose file name starts a-n are OK (these are
3109 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3111 if Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
3112 and then Name_Buffer (1 .. 3) /= "a-n"
3114 Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Declaration
3116 Error_Msg_N ("use clause not allowed in predefined spec", N);
3119 -- Chain clause to list of use clauses in current scope
3121 if Nkind (Parent (N)) /= N_Compilation_Unit then
3122 Chain_Use_Clause (N);
3125 -- Loop through package names to identify referenced packages
3127 Pack_Name := First (Names (N));
3128 while Present (Pack_Name) loop
3129 Analyze (Pack_Name);
3131 if Nkind (Parent (N)) = N_Compilation_Unit
3132 and then Nkind (Pack_Name) = N_Expanded_Name
3138 Pref := Prefix (Pack_Name);
3139 while Nkind (Pref) = N_Expanded_Name loop
3140 Pref := Prefix (Pref);
3143 if Entity (Pref) = Standard_Standard then
3145 ("predefined package Standard cannot appear"
3146 & " in a context clause", Pref);
3154 -- Loop through package names to mark all entities as potentially
3157 Pack_Name := First (Names (N));
3158 while Present (Pack_Name) loop
3159 if Is_Entity_Name (Pack_Name) then
3160 Pack := Entity (Pack_Name);
3162 if Ekind (Pack) /= E_Package and then Etype (Pack) /= Any_Type then
3163 if Ekind (Pack) = E_Generic_Package then
3164 Error_Msg_N -- CODEFIX
3165 ("a generic package is not allowed in a use clause",
3168 Error_Msg_N ("& is not a usable package", Pack_Name);
3172 if Nkind (Parent (N)) = N_Compilation_Unit then
3173 Check_In_Previous_With_Clause (N, Pack_Name);
3176 if Applicable_Use (Pack_Name) then
3177 Use_One_Package (Pack, N);
3181 -- Report error because name denotes something other than a package
3184 Error_Msg_N ("& is not a package", Pack_Name);
3189 end Analyze_Use_Package;
3191 ----------------------
3192 -- Analyze_Use_Type --
3193 ----------------------
3195 procedure Analyze_Use_Type (N : Node_Id) is
3200 Set_Hidden_By_Use_Clause (N, No_Elist);
3202 -- Chain clause to list of use clauses in current scope
3204 if Nkind (Parent (N)) /= N_Compilation_Unit then
3205 Chain_Use_Clause (N);
3208 -- If the Used_Operations list is already initialized, the clause has
3209 -- been analyzed previously, and it is begin reinstalled, for example
3210 -- when the clause appears in a package spec and we are compiling the
3211 -- corresponding package body. In that case, make the entities on the
3212 -- existing list use_visible, and mark the corresponding types In_Use.
3214 if Present (Used_Operations (N)) then
3220 Mark := First (Subtype_Marks (N));
3221 while Present (Mark) loop
3222 Use_One_Type (Mark, Installed => True);
3226 Elmt := First_Elmt (Used_Operations (N));
3227 while Present (Elmt) loop
3228 Set_Is_Potentially_Use_Visible (Node (Elmt));
3236 -- Otherwise, create new list and attach to it the operations that
3237 -- are made use-visible by the clause.
3239 Set_Used_Operations (N, New_Elmt_List);
3240 Id := First (Subtype_Marks (N));
3241 while Present (Id) loop
3245 if E /= Any_Type then
3248 if Nkind (Parent (N)) = N_Compilation_Unit then
3249 if Nkind (Id) = N_Identifier then
3250 Error_Msg_N ("type is not directly visible", Id);
3252 elsif Is_Child_Unit (Scope (E))
3253 and then Scope (E) /= System_Aux_Id
3255 Check_In_Previous_With_Clause (N, Prefix (Id));
3260 -- If the use_type_clause appears in a compilation unit context,
3261 -- check whether it comes from a unit that may appear in a
3262 -- limited_with_clause, for a better error message.
3264 if Nkind (Parent (N)) = N_Compilation_Unit
3265 and then Nkind (Id) /= N_Identifier
3271 function Mentioned (Nam : Node_Id) return Boolean;
3272 -- Check whether the prefix of expanded name for the type
3273 -- appears in the prefix of some limited_with_clause.
3279 function Mentioned (Nam : Node_Id) return Boolean is
3281 return Nkind (Name (Item)) = N_Selected_Component
3282 and then Chars (Prefix (Name (Item))) = Chars (Nam);
3286 Pref := Prefix (Id);
3287 Item := First (Context_Items (Parent (N)));
3288 while Present (Item) and then Item /= N loop
3289 if Nkind (Item) = N_With_Clause
3290 and then Limited_Present (Item)
3291 and then Mentioned (Pref)
3294 (Get_Msg_Id, "premature usage of incomplete type");
3305 end Analyze_Use_Type;
3307 --------------------
3308 -- Applicable_Use --
3309 --------------------
3311 function Applicable_Use (Pack_Name : Node_Id) return Boolean is
3312 Pack : constant Entity_Id := Entity (Pack_Name);
3315 if In_Open_Scopes (Pack) then
3316 if Warn_On_Redundant_Constructs and then Pack = Current_Scope then
3317 Error_Msg_NE -- CODEFIX
3318 ("& is already use-visible within itself?r?", Pack_Name, Pack);
3323 elsif In_Use (Pack) then
3324 Note_Redundant_Use (Pack_Name);
3327 elsif Present (Renamed_Object (Pack))
3328 and then In_Use (Renamed_Object (Pack))
3330 Note_Redundant_Use (Pack_Name);
3338 ------------------------
3339 -- Attribute_Renaming --
3340 ------------------------
3342 procedure Attribute_Renaming (N : Node_Id) is
3343 Loc : constant Source_Ptr := Sloc (N);
3344 Nam : constant Node_Id := Name (N);
3345 Spec : constant Node_Id := Specification (N);
3346 New_S : constant Entity_Id := Defining_Unit_Name (Spec);
3347 Aname : constant Name_Id := Attribute_Name (Nam);
3349 Form_Num : Nat := 0;
3350 Expr_List : List_Id := No_List;
3352 Attr_Node : Node_Id;
3353 Body_Node : Node_Id;
3354 Param_Spec : Node_Id;
3357 Generate_Definition (New_S);
3359 -- This procedure is called in the context of subprogram renaming, and
3360 -- thus the attribute must be one that is a subprogram. All of those
3361 -- have at least one formal parameter, with the exceptions of AST_Entry
3362 -- (which is a real oddity, it is odd that this can be renamed at all)
3363 -- and the GNAT attribute 'Img, which GNAT treats as renameable.
3365 if not Is_Non_Empty_List (Parameter_Specifications (Spec)) then
3366 if Aname /= Name_AST_Entry and then Aname /= Name_Img then
3368 ("subprogram renaming an attribute must have formals", N);
3373 Param_Spec := First (Parameter_Specifications (Spec));
3374 while Present (Param_Spec) loop
3375 Form_Num := Form_Num + 1;
3377 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
3378 Find_Type (Parameter_Type (Param_Spec));
3380 -- The profile of the new entity denotes the base type (s) of
3381 -- the types given in the specification. For access parameters
3382 -- there are no subtypes involved.
3384 Rewrite (Parameter_Type (Param_Spec),
3386 (Base_Type (Entity (Parameter_Type (Param_Spec))), Loc));
3389 if No (Expr_List) then
3390 Expr_List := New_List;
3393 Append_To (Expr_List,
3394 Make_Identifier (Loc,
3395 Chars => Chars (Defining_Identifier (Param_Spec))));
3397 -- The expressions in the attribute reference are not freeze
3398 -- points. Neither is the attribute as a whole, see below.
3400 Set_Must_Not_Freeze (Last (Expr_List));
3405 -- Immediate error if too many formals. Other mismatches in number or
3406 -- types of parameters are detected when we analyze the body of the
3407 -- subprogram that we construct.
3409 if Form_Num > 2 then
3410 Error_Msg_N ("too many formals for attribute", N);
3412 -- Error if the attribute reference has expressions that look like
3413 -- formal parameters.
3415 elsif Present (Expressions (Nam)) then
3416 Error_Msg_N ("illegal expressions in attribute reference", Nam);
3419 Nam_In (Aname, Name_Compose, Name_Exponent, Name_Leading_Part,
3420 Name_Pos, Name_Round, Name_Scaling,
3423 if Nkind (N) = N_Subprogram_Renaming_Declaration
3424 and then Present (Corresponding_Formal_Spec (N))
3427 ("generic actual cannot be attribute involving universal type",
3431 ("attribute involving a universal type cannot be renamed",
3436 -- AST_Entry is an odd case. It doesn't really make much sense to allow
3437 -- it to be renamed, but that's the DEC rule, so we have to do it right.
3438 -- The point is that the AST_Entry call should be made now, and what the
3439 -- function will return is the returned value.
3441 -- Note that there is no Expr_List in this case anyway
3443 if Aname = Name_AST_Entry then
3445 Ent : constant Entity_Id := Make_Temporary (Loc, 'R', Nam);
3450 Make_Object_Declaration (Loc,
3451 Defining_Identifier => Ent,
3452 Object_Definition =>
3453 New_Occurrence_Of (RTE (RE_AST_Handler), Loc),
3455 Constant_Present => True);
3457 Set_Assignment_OK (Decl, True);
3458 Insert_Action (N, Decl);
3459 Attr_Node := Make_Identifier (Loc, Chars (Ent));
3462 -- For all other attributes, we rewrite the attribute node to have
3463 -- a list of expressions corresponding to the subprogram formals.
3464 -- A renaming declaration is not a freeze point, and the analysis of
3465 -- the attribute reference should not freeze the type of the prefix.
3466 -- We use the original node in the renaming so that its source location
3467 -- is preserved, and checks on stream attributes are properly applied.
3470 Attr_Node := Relocate_Node (Nam);
3471 Set_Expressions (Attr_Node, Expr_List);
3473 Set_Must_Not_Freeze (Attr_Node);
3474 Set_Must_Not_Freeze (Prefix (Nam));
3477 -- Case of renaming a function
3479 if Nkind (Spec) = N_Function_Specification then
3480 if Is_Procedure_Attribute_Name (Aname) then
3481 Error_Msg_N ("attribute can only be renamed as procedure", Nam);
3485 Find_Type (Result_Definition (Spec));
3486 Rewrite (Result_Definition (Spec),
3488 (Base_Type (Entity (Result_Definition (Spec))), Loc));
3491 Make_Subprogram_Body (Loc,
3492 Specification => Spec,
3493 Declarations => New_List,
3494 Handled_Statement_Sequence =>
3495 Make_Handled_Sequence_Of_Statements (Loc,
3496 Statements => New_List (
3497 Make_Simple_Return_Statement (Loc,
3498 Expression => Attr_Node))));
3500 -- Case of renaming a procedure
3503 if not Is_Procedure_Attribute_Name (Aname) then
3504 Error_Msg_N ("attribute can only be renamed as function", Nam);
3509 Make_Subprogram_Body (Loc,
3510 Specification => Spec,
3511 Declarations => New_List,
3512 Handled_Statement_Sequence =>
3513 Make_Handled_Sequence_Of_Statements (Loc,
3514 Statements => New_List (Attr_Node)));
3517 -- In case of tagged types we add the body of the generated function to
3518 -- the freezing actions of the type (because in the general case such
3519 -- type is still not frozen). We exclude from this processing generic
3520 -- formal subprograms found in instantiations and AST_Entry renamings.
3522 -- We must exclude VM targets and restricted run-time libraries because
3523 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3524 -- available in those platforms. Note that we cannot use the function
3525 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3526 -- the ZFP run-time library is not defined as a profile, and we do not
3527 -- want to deal with AST_Handler in ZFP mode.
3529 if VM_Target = No_VM
3530 and then not Configurable_Run_Time_Mode
3531 and then not Present (Corresponding_Formal_Spec (N))
3532 and then Etype (Nam) /= RTE (RE_AST_Handler)
3535 P : constant Node_Id := Prefix (Nam);
3538 -- The prefix of 'Img is an object that is evaluated for each call
3539 -- of the function that renames it.
3541 if Aname = Name_Img then
3542 Preanalyze_And_Resolve (P);
3544 -- For all other attribute renamings, the prefix is a subtype
3550 -- If the target type is not yet frozen, add the body to the
3551 -- actions to be elaborated at freeze time.
3553 if Is_Tagged_Type (Etype (P))
3554 and then In_Open_Scopes (Scope (Etype (P)))
3556 Ensure_Freeze_Node (Etype (P));
3557 Append_Freeze_Action (Etype (P), Body_Node);
3559 Rewrite (N, Body_Node);
3561 Set_Etype (New_S, Base_Type (Etype (New_S)));
3565 -- Generic formal subprograms or AST_Handler renaming
3568 Rewrite (N, Body_Node);
3570 Set_Etype (New_S, Base_Type (Etype (New_S)));
3573 if Is_Compilation_Unit (New_S) then
3575 ("a library unit can only rename another library unit", N);
3578 -- We suppress elaboration warnings for the resulting entity, since
3579 -- clearly they are not needed, and more particularly, in the case
3580 -- of a generic formal subprogram, the resulting entity can appear
3581 -- after the instantiation itself, and thus look like a bogus case
3582 -- of access before elaboration.
3584 Set_Suppress_Elaboration_Warnings (New_S);
3586 end Attribute_Renaming;
3588 ----------------------
3589 -- Chain_Use_Clause --
3590 ----------------------
3592 procedure Chain_Use_Clause (N : Node_Id) is
3594 Level : Int := Scope_Stack.Last;
3597 if not Is_Compilation_Unit (Current_Scope)
3598 or else not Is_Child_Unit (Current_Scope)
3600 null; -- Common case
3602 elsif Defining_Entity (Parent (N)) = Current_Scope then
3603 null; -- Common case for compilation unit
3606 -- If declaration appears in some other scope, it must be in some
3607 -- parent unit when compiling a child.
3609 Pack := Defining_Entity (Parent (N));
3610 if not In_Open_Scopes (Pack) then
3611 null; -- default as well
3614 -- Find entry for parent unit in scope stack
3616 while Scope_Stack.Table (Level).Entity /= Pack loop
3622 Set_Next_Use_Clause (N,
3623 Scope_Stack.Table (Level).First_Use_Clause);
3624 Scope_Stack.Table (Level).First_Use_Clause := N;
3625 end Chain_Use_Clause;
3627 ---------------------------
3628 -- Check_Frozen_Renaming --
3629 ---------------------------
3631 procedure Check_Frozen_Renaming (N : Node_Id; Subp : Entity_Id) is
3636 if Is_Frozen (Subp) and then not Has_Completion (Subp) then
3639 (Parent (Declaration_Node (Subp)), Defining_Entity (N));
3641 if Is_Entity_Name (Name (N)) then
3642 Old_S := Entity (Name (N));
3644 if not Is_Frozen (Old_S)
3645 and then Operating_Mode /= Check_Semantics
3647 Append_Freeze_Action (Old_S, B_Node);
3649 Insert_After (N, B_Node);
3653 if Is_Intrinsic_Subprogram (Old_S) and then not In_Instance then
3655 ("subprogram used in renaming_as_body cannot be intrinsic",
3660 Insert_After (N, B_Node);
3664 end Check_Frozen_Renaming;
3666 -------------------------------
3667 -- Set_Entity_Or_Discriminal --
3668 -------------------------------
3670 procedure Set_Entity_Or_Discriminal (N : Node_Id; E : Entity_Id) is
3674 -- If the entity is not a discriminant, or else expansion is disabled,
3675 -- simply set the entity.
3677 if not In_Spec_Expression
3678 or else Ekind (E) /= E_Discriminant
3679 or else Inside_A_Generic
3681 Set_Entity_With_Checks (N, E);
3683 -- The replacement of a discriminant by the corresponding discriminal
3684 -- is not done for a task discriminant that appears in a default
3685 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
3686 -- for details on their handling.
3688 elsif Is_Concurrent_Type (Scope (E)) then
3691 and then not Nkind_In (P, N_Parameter_Specification,
3692 N_Component_Declaration)
3698 and then Nkind (P) = N_Parameter_Specification
3703 Set_Entity (N, Discriminal (E));
3706 -- Otherwise, this is a discriminant in a context in which
3707 -- it is a reference to the corresponding parameter of the
3708 -- init proc for the enclosing type.
3711 Set_Entity (N, Discriminal (E));
3713 end Set_Entity_Or_Discriminal;
3715 -----------------------------------
3716 -- Check_In_Previous_With_Clause --
3717 -----------------------------------
3719 procedure Check_In_Previous_With_Clause
3723 Pack : constant Entity_Id := Entity (Original_Node (Nam));
3728 Item := First (Context_Items (Parent (N)));
3729 while Present (Item) and then Item /= N loop
3730 if Nkind (Item) = N_With_Clause
3732 -- Protect the frontend against previous critical errors
3734 and then Nkind (Name (Item)) /= N_Selected_Component
3735 and then Entity (Name (Item)) = Pack
3739 -- Find root library unit in with_clause
3741 while Nkind (Par) = N_Expanded_Name loop
3742 Par := Prefix (Par);
3745 if Is_Child_Unit (Entity (Original_Node (Par))) then
3746 Error_Msg_NE ("& is not directly visible", Par, Entity (Par));
3755 -- On exit, package is not mentioned in a previous with_clause.
3756 -- Check if its prefix is.
3758 if Nkind (Nam) = N_Expanded_Name then
3759 Check_In_Previous_With_Clause (N, Prefix (Nam));
3761 elsif Pack /= Any_Id then
3762 Error_Msg_NE ("& is not visible", Nam, Pack);
3764 end Check_In_Previous_With_Clause;
3766 ---------------------------------
3767 -- Check_Library_Unit_Renaming --
3768 ---------------------------------
3770 procedure Check_Library_Unit_Renaming (N : Node_Id; Old_E : Entity_Id) is
3774 if Nkind (Parent (N)) /= N_Compilation_Unit then
3777 -- Check for library unit. Note that we used to check for the scope
3778 -- being Standard here, but that was wrong for Standard itself.
3780 elsif not Is_Compilation_Unit (Old_E)
3781 and then not Is_Child_Unit (Old_E)
3783 Error_Msg_N ("renamed unit must be a library unit", Name (N));
3785 -- Entities defined in Standard (operators and boolean literals) cannot
3786 -- be renamed as library units.
3788 elsif Scope (Old_E) = Standard_Standard
3789 and then Sloc (Old_E) = Standard_Location
3791 Error_Msg_N ("renamed unit must be a library unit", Name (N));
3793 elsif Present (Parent_Spec (N))
3794 and then Nkind (Unit (Parent_Spec (N))) = N_Generic_Package_Declaration
3795 and then not Is_Child_Unit (Old_E)
3798 ("renamed unit must be a child unit of generic parent", Name (N));
3800 elsif Nkind (N) in N_Generic_Renaming_Declaration
3801 and then Nkind (Name (N)) = N_Expanded_Name
3802 and then Is_Generic_Instance (Entity (Prefix (Name (N))))
3803 and then Is_Generic_Unit (Old_E)
3806 ("renamed generic unit must be a library unit", Name (N));
3808 elsif Is_Package_Or_Generic_Package (Old_E) then
3810 -- Inherit categorization flags
3812 New_E := Defining_Entity (N);
3813 Set_Is_Pure (New_E, Is_Pure (Old_E));
3814 Set_Is_Preelaborated (New_E, Is_Preelaborated (Old_E));
3815 Set_Is_Remote_Call_Interface (New_E,
3816 Is_Remote_Call_Interface (Old_E));
3817 Set_Is_Remote_Types (New_E, Is_Remote_Types (Old_E));
3818 Set_Is_Shared_Passive (New_E, Is_Shared_Passive (Old_E));
3820 end Check_Library_Unit_Renaming;
3822 ------------------------
3823 -- Enclosing_Instance --
3824 ------------------------
3826 function Enclosing_Instance return Entity_Id is
3830 if not Is_Generic_Instance (Current_Scope) then
3834 S := Scope (Current_Scope);
3835 while S /= Standard_Standard loop
3836 if Is_Generic_Instance (S) then
3844 end Enclosing_Instance;
3850 procedure End_Scope is
3856 Id := First_Entity (Current_Scope);
3857 while Present (Id) loop
3858 -- An entity in the current scope is not necessarily the first one
3859 -- on its homonym chain. Find its predecessor if any,
3860 -- If it is an internal entity, it will not be in the visibility
3861 -- chain altogether, and there is nothing to unchain.
3863 if Id /= Current_Entity (Id) then
3864 Prev := Current_Entity (Id);
3865 while Present (Prev)
3866 and then Present (Homonym (Prev))
3867 and then Homonym (Prev) /= Id
3869 Prev := Homonym (Prev);
3872 -- Skip to end of loop if Id is not in the visibility chain
3874 if No (Prev) or else Homonym (Prev) /= Id then
3882 Set_Is_Immediately_Visible (Id, False);
3884 Outer := Homonym (Id);
3885 while Present (Outer) and then Scope (Outer) = Current_Scope loop
3886 Outer := Homonym (Outer);
3889 -- Reset homonym link of other entities, but do not modify link
3890 -- between entities in current scope, so that the back-end can have
3891 -- a proper count of local overloadings.
3894 Set_Name_Entity_Id (Chars (Id), Outer);
3896 elsif Scope (Prev) /= Scope (Id) then
3897 Set_Homonym (Prev, Outer);
3904 -- If the scope generated freeze actions, place them before the
3905 -- current declaration and analyze them. Type declarations and
3906 -- the bodies of initialization procedures can generate such nodes.
3907 -- We follow the parent chain until we reach a list node, which is
3908 -- the enclosing list of declarations. If the list appears within
3909 -- a protected definition, move freeze nodes outside the protected
3913 (Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions)
3917 L : constant List_Id := Scope_Stack.Table
3918 (Scope_Stack.Last).Pending_Freeze_Actions;
3921 if Is_Itype (Current_Scope) then
3922 Decl := Associated_Node_For_Itype (Current_Scope);
3924 Decl := Parent (Current_Scope);
3929 while not (Is_List_Member (Decl))
3930 or else Nkind_In (Parent (Decl), N_Protected_Definition,
3933 Decl := Parent (Decl);
3936 Insert_List_Before_And_Analyze (Decl, L);
3945 ---------------------
3946 -- End_Use_Clauses --
3947 ---------------------
3949 procedure End_Use_Clauses (Clause : Node_Id) is
3953 -- Remove Use_Type clauses first, because they affect the
3954 -- visibility of operators in subsequent used packages.
3957 while Present (U) loop
3958 if Nkind (U) = N_Use_Type_Clause then
3962 Next_Use_Clause (U);
3966 while Present (U) loop
3967 if Nkind (U) = N_Use_Package_Clause then
3968 End_Use_Package (U);
3971 Next_Use_Clause (U);
3973 end End_Use_Clauses;
3975 ---------------------
3976 -- End_Use_Package --
3977 ---------------------
3979 procedure End_Use_Package (N : Node_Id) is
3980 Pack_Name : Node_Id;
3985 function Is_Primitive_Operator_In_Use
3987 F : Entity_Id) return Boolean;
3988 -- Check whether Op is a primitive operator of a use-visible type
3990 ----------------------------------
3991 -- Is_Primitive_Operator_In_Use --
3992 ----------------------------------
3994 function Is_Primitive_Operator_In_Use
3996 F : Entity_Id) return Boolean
3998 T : constant Entity_Id := Base_Type (Etype (F));
4000 return In_Use (T) and then Scope (T) = Scope (Op);
4001 end Is_Primitive_Operator_In_Use;
4003 -- Start of processing for End_Use_Package
4006 Pack_Name := First (Names (N));
4007 while Present (Pack_Name) loop
4009 -- Test that Pack_Name actually denotes a package before processing
4011 if Is_Entity_Name (Pack_Name)
4012 and then Ekind (Entity (Pack_Name)) = E_Package
4014 Pack := Entity (Pack_Name);
4016 if In_Open_Scopes (Pack) then
4019 elsif not Redundant_Use (Pack_Name) then
4020 Set_In_Use (Pack, False);
4021 Set_Current_Use_Clause (Pack, Empty);
4023 Id := First_Entity (Pack);
4024 while Present (Id) loop
4026 -- Preserve use-visibility of operators that are primitive
4027 -- operators of a type that is use-visible through an active
4030 if Nkind (Id) = N_Defining_Operator_Symbol
4032 (Is_Primitive_Operator_In_Use (Id, First_Formal (Id))
4034 (Present (Next_Formal (First_Formal (Id)))
4036 Is_Primitive_Operator_In_Use
4037 (Id, Next_Formal (First_Formal (Id)))))
4041 Set_Is_Potentially_Use_Visible (Id, False);
4044 if Is_Private_Type (Id)
4045 and then Present (Full_View (Id))
4047 Set_Is_Potentially_Use_Visible (Full_View (Id), False);
4053 if Present (Renamed_Object (Pack)) then
4054 Set_In_Use (Renamed_Object (Pack), False);
4055 Set_Current_Use_Clause (Renamed_Object (Pack), Empty);
4058 if Chars (Pack) = Name_System
4059 and then Scope (Pack) = Standard_Standard
4060 and then Present_System_Aux
4062 Id := First_Entity (System_Aux_Id);
4063 while Present (Id) loop
4064 Set_Is_Potentially_Use_Visible (Id, False);
4066 if Is_Private_Type (Id)
4067 and then Present (Full_View (Id))
4069 Set_Is_Potentially_Use_Visible (Full_View (Id), False);
4075 Set_In_Use (System_Aux_Id, False);
4079 Set_Redundant_Use (Pack_Name, False);
4086 if Present (Hidden_By_Use_Clause (N)) then
4087 Elmt := First_Elmt (Hidden_By_Use_Clause (N));
4088 while Present (Elmt) loop
4090 E : constant Entity_Id := Node (Elmt);
4093 -- Reset either Use_Visibility or Direct_Visibility, depending
4094 -- on how the entity was hidden by the use clause.
4096 if In_Use (Scope (E))
4097 and then Used_As_Generic_Actual (Scope (E))
4099 Set_Is_Potentially_Use_Visible (Node (Elmt));
4101 Set_Is_Immediately_Visible (Node (Elmt));
4108 Set_Hidden_By_Use_Clause (N, No_Elist);
4110 end End_Use_Package;
4116 procedure End_Use_Type (N : Node_Id) is
4121 -- Start of processing for End_Use_Type
4124 Id := First (Subtype_Marks (N));
4125 while Present (Id) loop
4127 -- A call to Rtsfind may occur while analyzing a use_type clause,
4128 -- in which case the type marks are not resolved yet, and there is
4129 -- nothing to remove.
4131 if not Is_Entity_Name (Id) or else No (Entity (Id)) then
4137 if T = Any_Type or else From_Limited_With (T) then
4140 -- Note that the use_type clause may mention a subtype of the type
4141 -- whose primitive operations have been made visible. Here as
4142 -- elsewhere, it is the base type that matters for visibility.
4144 elsif In_Open_Scopes (Scope (Base_Type (T))) then
4147 elsif not Redundant_Use (Id) then
4148 Set_In_Use (T, False);
4149 Set_In_Use (Base_Type (T), False);
4150 Set_Current_Use_Clause (T, Empty);
4151 Set_Current_Use_Clause (Base_Type (T), Empty);
4158 if Is_Empty_Elmt_List (Used_Operations (N)) then
4162 Elmt := First_Elmt (Used_Operations (N));
4163 while Present (Elmt) loop
4164 Set_Is_Potentially_Use_Visible (Node (Elmt), False);
4170 ----------------------
4171 -- Find_Direct_Name --
4172 ----------------------
4174 procedure Find_Direct_Name (N : Node_Id) is
4179 Inst : Entity_Id := Empty;
4180 -- Enclosing instance, if any
4182 Homonyms : Entity_Id;
4183 -- Saves start of homonym chain
4185 Nvis_Entity : Boolean;
4186 -- Set True to indicate that there is at least one entity on the homonym
4187 -- chain which, while not visible, is visible enough from the user point
4188 -- of view to warrant an error message of "not visible" rather than
4191 Nvis_Is_Private_Subprg : Boolean := False;
4192 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4193 -- effect concerning library subprograms has been detected. Used to
4194 -- generate the precise error message.
4196 function From_Actual_Package (E : Entity_Id) return Boolean;
4197 -- Returns true if the entity is an actual for a package that is itself
4198 -- an actual for a formal package of the current instance. Such an
4199 -- entity requires special handling because it may be use-visible but
4200 -- hides directly visible entities defined outside the instance, because
4201 -- the corresponding formal did so in the generic.
4203 function Is_Actual_Parameter return Boolean;
4204 -- This function checks if the node N is an identifier that is an actual
4205 -- parameter of a procedure call. If so it returns True, otherwise it
4206 -- return False. The reason for this check is that at this stage we do
4207 -- not know what procedure is being called if the procedure might be
4208 -- overloaded, so it is premature to go setting referenced flags or
4209 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4210 -- for that processing
4212 function Known_But_Invisible (E : Entity_Id) return Boolean;
4213 -- This function determines whether the entity E (which is not
4214 -- visible) can reasonably be considered to be known to the writer
4215 -- of the reference. This is a heuristic test, used only for the
4216 -- purposes of figuring out whether we prefer to complain that an
4217 -- entity is undefined or invisible (and identify the declaration
4218 -- of the invisible entity in the latter case). The point here is
4219 -- that we don't want to complain that something is invisible and
4220 -- then point to something entirely mysterious to the writer.
4222 procedure Nvis_Messages;
4223 -- Called if there are no visible entries for N, but there is at least
4224 -- one non-directly visible, or hidden declaration. This procedure
4225 -- outputs an appropriate set of error messages.
4227 procedure Undefined (Nvis : Boolean);
4228 -- This function is called if the current node has no corresponding
4229 -- visible entity or entities. The value set in Msg indicates whether
4230 -- an error message was generated (multiple error messages for the
4231 -- same variable are generally suppressed, see body for details).
4232 -- Msg is True if an error message was generated, False if not. This
4233 -- value is used by the caller to determine whether or not to output
4234 -- additional messages where appropriate. The parameter is set False
4235 -- to get the message "X is undefined", and True to get the message
4236 -- "X is not visible".
4238 -------------------------
4239 -- From_Actual_Package --
4240 -------------------------
4242 function From_Actual_Package (E : Entity_Id) return Boolean is
4243 Scop : constant Entity_Id := Scope (E);
4244 -- Declared scope of candidate entity
4248 function Declared_In_Actual (Pack : Entity_Id) return Boolean;
4249 -- Recursive function that does the work and examines actuals of
4250 -- actual packages of current instance.
4252 ------------------------
4253 -- Declared_In_Actual --
4254 ------------------------
4256 function Declared_In_Actual (Pack : Entity_Id) return Boolean is
4260 if No (Associated_Formal_Package (Pack)) then
4264 Act := First_Entity (Pack);
4265 while Present (Act) loop
4266 if Renamed_Object (Pack) = Scop then
4269 -- Check for end of list of actuals.
4271 elsif Ekind (Act) = E_Package
4272 and then Renamed_Object (Act) = Pack
4276 elsif Ekind (Act) = E_Package
4277 and then Declared_In_Actual (Act)
4287 end Declared_In_Actual;
4289 -- Start of processing for From_Actual_Package
4292 if not In_Instance then
4296 Inst := Current_Scope;
4297 while Present (Inst)
4298 and then Ekind (Inst) /= E_Package
4299 and then not Is_Generic_Instance (Inst)
4301 Inst := Scope (Inst);
4308 Act := First_Entity (Inst);
4309 while Present (Act) loop
4310 if Ekind (Act) = E_Package
4311 and then Declared_In_Actual (Act)
4321 end From_Actual_Package;
4323 -------------------------
4324 -- Is_Actual_Parameter --
4325 -------------------------
4327 function Is_Actual_Parameter return Boolean is
4330 Nkind (N) = N_Identifier
4332 (Nkind (Parent (N)) = N_Procedure_Call_Statement
4334 (Nkind (Parent (N)) = N_Parameter_Association
4335 and then N = Explicit_Actual_Parameter (Parent (N))
4336 and then Nkind (Parent (Parent (N))) =
4337 N_Procedure_Call_Statement));
4338 end Is_Actual_Parameter;
4340 -------------------------
4341 -- Known_But_Invisible --
4342 -------------------------
4344 function Known_But_Invisible (E : Entity_Id) return Boolean is
4345 Fname : File_Name_Type;
4348 -- Entities in Standard are always considered to be known
4350 if Sloc (E) <= Standard_Location then
4353 -- An entity that does not come from source is always considered
4354 -- to be unknown, since it is an artifact of code expansion.
4356 elsif not Comes_From_Source (E) then
4359 -- In gnat internal mode, we consider all entities known
4361 elsif GNAT_Mode then
4365 -- Here we have an entity that is not from package Standard, and
4366 -- which comes from Source. See if it comes from an internal file.
4368 Fname := Unit_File_Name (Get_Source_Unit (E));
4370 -- Case of from internal file
4372 if Is_Internal_File_Name (Fname) then
4374 -- Private part entities in internal files are never considered
4375 -- to be known to the writer of normal application code.
4377 if Is_Hidden (E) then
4381 -- Entities from System packages other than System and
4382 -- System.Storage_Elements are not considered to be known.
4383 -- System.Auxxxx files are also considered known to the user.
4385 -- Should refine this at some point to generally distinguish
4386 -- between known and unknown internal files ???
4388 Get_Name_String (Fname);
4393 Name_Buffer (1 .. 2) /= "s-"
4395 Name_Buffer (3 .. 8) = "stoele"
4397 Name_Buffer (3 .. 5) = "aux";
4399 -- If not an internal file, then entity is definitely known,
4400 -- even if it is in a private part (the message generated will
4401 -- note that it is in a private part)
4406 end Known_But_Invisible;
4412 procedure Nvis_Messages is
4413 Comp_Unit : Node_Id;
4415 Found : Boolean := False;
4416 Hidden : Boolean := False;
4420 -- Ada 2005 (AI-262): Generate a precise error concerning the
4421 -- Beaujolais effect that was previously detected
4423 if Nvis_Is_Private_Subprg then
4425 pragma Assert (Nkind (E2) = N_Defining_Identifier
4426 and then Ekind (E2) = E_Function
4427 and then Scope (E2) = Standard_Standard
4428 and then Has_Private_With (E2));
4430 -- Find the sloc corresponding to the private with'ed unit
4432 Comp_Unit := Cunit (Current_Sem_Unit);
4433 Error_Msg_Sloc := No_Location;
4435 Item := First (Context_Items (Comp_Unit));
4436 while Present (Item) loop
4437 if Nkind (Item) = N_With_Clause
4438 and then Private_Present (Item)
4439 and then Entity (Name (Item)) = E2
4441 Error_Msg_Sloc := Sloc (Item);
4448 pragma Assert (Error_Msg_Sloc /= No_Location);
4450 Error_Msg_N ("(Ada 2005): hidden by private with clause #", N);
4454 Undefined (Nvis => True);
4458 -- First loop does hidden declarations
4461 while Present (Ent) loop
4462 if Is_Potentially_Use_Visible (Ent) then
4464 Error_Msg_N -- CODEFIX
4465 ("multiple use clauses cause hiding!", N);
4469 Error_Msg_Sloc := Sloc (Ent);
4470 Error_Msg_N -- CODEFIX
4471 ("hidden declaration#!", N);
4474 Ent := Homonym (Ent);
4477 -- If we found hidden declarations, then that's enough, don't
4478 -- bother looking for non-visible declarations as well.
4484 -- Second loop does non-directly visible declarations
4487 while Present (Ent) loop
4488 if not Is_Potentially_Use_Visible (Ent) then
4490 -- Do not bother the user with unknown entities
4492 if not Known_But_Invisible (Ent) then
4496 Error_Msg_Sloc := Sloc (Ent);
4498 -- Output message noting that there is a non-visible
4499 -- declaration, distinguishing the private part case.
4501 if Is_Hidden (Ent) then
4502 Error_Msg_N ("non-visible (private) declaration#!", N);
4504 -- If the entity is declared in a generic package, it
4505 -- cannot be visible, so there is no point in adding it
4506 -- to the list of candidates if another homograph from a
4507 -- non-generic package has been seen.
4509 elsif Ekind (Scope (Ent)) = E_Generic_Package
4515 Error_Msg_N -- CODEFIX
4516 ("non-visible declaration#!", N);
4518 if Ekind (Scope (Ent)) /= E_Generic_Package then
4522 if Is_Compilation_Unit (Ent)
4524 Nkind (Parent (Parent (N))) = N_Use_Package_Clause
4526 Error_Msg_Qual_Level := 99;
4527 Error_Msg_NE -- CODEFIX
4528 ("\\missing `WITH &;`", N, Ent);
4529 Error_Msg_Qual_Level := 0;
4532 if Ekind (Ent) = E_Discriminant
4533 and then Present (Corresponding_Discriminant (Ent))
4534 and then Scope (Corresponding_Discriminant (Ent)) =
4538 ("inherited discriminant not allowed here" &
4539 " (RM 3.8 (12), 3.8.1 (6))!", N);
4543 -- Set entity and its containing package as referenced. We
4544 -- can't be sure of this, but this seems a better choice
4545 -- to avoid unused entity messages.
4547 if Comes_From_Source (Ent) then
4548 Set_Referenced (Ent);
4549 Set_Referenced (Cunit_Entity (Get_Source_Unit (Ent)));
4554 Ent := Homonym (Ent);
4563 procedure Undefined (Nvis : Boolean) is
4564 Emsg : Error_Msg_Id;
4567 -- We should never find an undefined internal name. If we do, then
4568 -- see if we have previous errors. If so, ignore on the grounds that
4569 -- it is probably a cascaded message (e.g. a block label from a badly
4570 -- formed block). If no previous errors, then we have a real internal
4571 -- error of some kind so raise an exception.
4573 if Is_Internal_Name (Chars (N)) then
4574 if Total_Errors_Detected /= 0 then
4577 raise Program_Error;
4581 -- A very specialized error check, if the undefined variable is
4582 -- a case tag, and the case type is an enumeration type, check
4583 -- for a possible misspelling, and if so, modify the identifier
4585 -- Named aggregate should also be handled similarly ???
4587 if Nkind (N) = N_Identifier
4588 and then Nkind (Parent (N)) = N_Case_Statement_Alternative
4591 Case_Stm : constant Node_Id := Parent (Parent (N));
4592 Case_Typ : constant Entity_Id := Etype (Expression (Case_Stm));
4597 if Is_Enumeration_Type (Case_Typ)
4598 and then not Is_Standard_Character_Type (Case_Typ)
4600 Lit := First_Literal (Case_Typ);
4601 Get_Name_String (Chars (Lit));
4603 if Chars (Lit) /= Chars (N)
4604 and then Is_Bad_Spelling_Of (Chars (N), Chars (Lit))
4606 Error_Msg_Node_2 := Lit;
4607 Error_Msg_N -- CODEFIX
4608 ("& is undefined, assume misspelling of &", N);
4609 Rewrite (N, New_Occurrence_Of (Lit, Sloc (N)));
4613 Lit := Next_Literal (Lit);
4618 -- Normal processing
4620 Set_Entity (N, Any_Id);
4621 Set_Etype (N, Any_Type);
4623 -- We use the table Urefs to keep track of entities for which we
4624 -- have issued errors for undefined references. Multiple errors
4625 -- for a single name are normally suppressed, however we modify
4626 -- the error message to alert the programmer to this effect.
4628 for J in Urefs.First .. Urefs.Last loop
4629 if Chars (N) = Chars (Urefs.Table (J).Node) then
4630 if Urefs.Table (J).Err /= No_Error_Msg
4631 and then Sloc (N) /= Urefs.Table (J).Loc
4633 Error_Msg_Node_1 := Urefs.Table (J).Node;
4635 if Urefs.Table (J).Nvis then
4636 Change_Error_Text (Urefs.Table (J).Err,
4637 "& is not visible (more references follow)");
4639 Change_Error_Text (Urefs.Table (J).Err,
4640 "& is undefined (more references follow)");
4643 Urefs.Table (J).Err := No_Error_Msg;
4646 -- Although we will set Msg False, and thus suppress the
4647 -- message, we also set Error_Posted True, to avoid any
4648 -- cascaded messages resulting from the undefined reference.
4651 Set_Error_Posted (N, True);
4656 -- If entry not found, this is first undefined occurrence
4659 Error_Msg_N ("& is not visible!", N);
4663 Error_Msg_N ("& is undefined!", N);
4666 -- A very bizarre special check, if the undefined identifier
4667 -- is put or put_line, then add a special error message (since
4668 -- this is a very common error for beginners to make).
4670 if Nam_In (Chars (N), Name_Put, Name_Put_Line) then
4671 Error_Msg_N -- CODEFIX
4672 ("\\possible missing `WITH Ada.Text_'I'O; " &
4673 "USE Ada.Text_'I'O`!", N);
4675 -- Another special check if N is the prefix of a selected
4676 -- component which is a known unit, add message complaining
4677 -- about missing with for this unit.
4679 elsif Nkind (Parent (N)) = N_Selected_Component
4680 and then N = Prefix (Parent (N))
4681 and then Is_Known_Unit (Parent (N))
4683 Error_Msg_Node_2 := Selector_Name (Parent (N));
4684 Error_Msg_N -- CODEFIX
4685 ("\\missing `WITH &.&;`", Prefix (Parent (N)));
4688 -- Now check for possible misspellings
4692 Ematch : Entity_Id := Empty;
4694 Last_Name_Id : constant Name_Id :=
4695 Name_Id (Nat (First_Name_Id) +
4696 Name_Entries_Count - 1);
4699 for Nam in First_Name_Id .. Last_Name_Id loop
4700 E := Get_Name_Entity_Id (Nam);
4703 and then (Is_Immediately_Visible (E)
4705 Is_Potentially_Use_Visible (E))
4707 if Is_Bad_Spelling_Of (Chars (N), Nam) then
4714 if Present (Ematch) then
4715 Error_Msg_NE -- CODEFIX
4716 ("\possible misspelling of&", N, Ematch);
4721 -- Make entry in undefined references table unless the full errors
4722 -- switch is set, in which case by refraining from generating the
4723 -- table entry, we guarantee that we get an error message for every
4724 -- undefined reference.
4726 if not All_Errors_Mode then
4737 -- Start of processing for Find_Direct_Name
4740 -- If the entity pointer is already set, this is an internal node, or
4741 -- a node that is analyzed more than once, after a tree modification.
4742 -- In such a case there is no resolution to perform, just set the type.
4744 if Present (Entity (N)) then
4745 if Is_Type (Entity (N)) then
4746 Set_Etype (N, Entity (N));
4750 Entyp : constant Entity_Id := Etype (Entity (N));
4753 -- One special case here. If the Etype field is already set,
4754 -- and references the packed array type corresponding to the
4755 -- etype of the referenced entity, then leave it alone. This
4756 -- happens for trees generated from Exp_Pakd, where expressions
4757 -- can be deliberately "mis-typed" to the packed array type.
4759 if Is_Array_Type (Entyp)
4760 and then Is_Packed (Entyp)
4761 and then Present (Etype (N))
4762 and then Etype (N) = Packed_Array_Type (Entyp)
4766 -- If not that special case, then just reset the Etype
4769 Set_Etype (N, Etype (Entity (N)));
4777 -- Here if Entity pointer was not set, we need full visibility analysis
4778 -- First we generate debugging output if the debug E flag is set.
4780 if Debug_Flag_E then
4781 Write_Str ("Looking for ");
4782 Write_Name (Chars (N));
4786 Homonyms := Current_Entity (N);
4787 Nvis_Entity := False;
4790 while Present (E) loop
4792 -- If entity is immediately visible or potentially use visible, then
4793 -- process the entity and we are done.
4795 if Is_Immediately_Visible (E) then
4796 goto Immediately_Visible_Entity;
4798 elsif Is_Potentially_Use_Visible (E) then
4799 goto Potentially_Use_Visible_Entity;
4801 -- Note if a known but invisible entity encountered
4803 elsif Known_But_Invisible (E) then
4804 Nvis_Entity := True;
4807 -- Move to next entity in chain and continue search
4812 -- If no entries on homonym chain that were potentially visible,
4813 -- and no entities reasonably considered as non-visible, then
4814 -- we have a plain undefined reference, with no additional
4815 -- explanation required.
4817 if not Nvis_Entity then
4818 Undefined (Nvis => False);
4820 -- Otherwise there is at least one entry on the homonym chain that
4821 -- is reasonably considered as being known and non-visible.
4829 -- Processing for a potentially use visible entry found. We must search
4830 -- the rest of the homonym chain for two reasons. First, if there is a
4831 -- directly visible entry, then none of the potentially use-visible
4832 -- entities are directly visible (RM 8.4(10)). Second, we need to check
4833 -- for the case of multiple potentially use-visible entries hiding one
4834 -- another and as a result being non-directly visible (RM 8.4(11)).
4836 <<Potentially_Use_Visible_Entity>> declare
4837 Only_One_Visible : Boolean := True;
4838 All_Overloadable : Boolean := Is_Overloadable (E);
4842 while Present (E2) loop
4843 if Is_Immediately_Visible (E2) then
4845 -- If the use-visible entity comes from the actual for a
4846 -- formal package, it hides a directly visible entity from
4847 -- outside the instance.
4849 if From_Actual_Package (E)
4850 and then Scope_Depth (E2) < Scope_Depth (Inst)
4855 goto Immediately_Visible_Entity;
4858 elsif Is_Potentially_Use_Visible (E2) then
4859 Only_One_Visible := False;
4860 All_Overloadable := All_Overloadable and Is_Overloadable (E2);
4862 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
4863 -- that can occur in private_with clauses. Example:
4866 -- private with B; package A is
4867 -- package C is function B return Integer;
4869 -- V1 : Integer := B;
4870 -- private function B return Integer;
4871 -- V2 : Integer := B;
4874 -- V1 resolves to A.B, but V2 resolves to library unit B
4876 elsif Ekind (E2) = E_Function
4877 and then Scope (E2) = Standard_Standard
4878 and then Has_Private_With (E2)
4880 Only_One_Visible := False;
4881 All_Overloadable := False;
4882 Nvis_Is_Private_Subprg := True;
4889 -- On falling through this loop, we have checked that there are no
4890 -- immediately visible entities. Only_One_Visible is set if exactly
4891 -- one potentially use visible entity exists. All_Overloadable is
4892 -- set if all the potentially use visible entities are overloadable.
4893 -- The condition for legality is that either there is one potentially
4894 -- use visible entity, or if there is more than one, then all of them
4895 -- are overloadable.
4897 if Only_One_Visible or All_Overloadable then
4900 -- If there is more than one potentially use-visible entity and at
4901 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
4902 -- Note that E points to the first such entity on the homonym list.
4903 -- Special case: if one of the entities is declared in an actual
4904 -- package, it was visible in the generic, and takes precedence over
4905 -- other entities that are potentially use-visible. Same if it is
4906 -- declared in a local instantiation of the current instance.
4911 -- Find current instance
4913 Inst := Current_Scope;
4914 while Present (Inst) and then Inst /= Standard_Standard loop
4915 if Is_Generic_Instance (Inst) then
4919 Inst := Scope (Inst);
4923 while Present (E2) loop
4924 if From_Actual_Package (E2)
4926 (Is_Generic_Instance (Scope (E2))
4927 and then Scope_Depth (Scope (E2)) > Scope_Depth (Inst))
4940 Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
4942 -- A use-clause in the body of a system file creates conflict
4943 -- with some entity in a user scope, while rtsfind is active.
4944 -- Keep only the entity coming from another predefined unit.
4947 while Present (E2) loop
4948 if Is_Predefined_File_Name
4949 (Unit_File_Name (Get_Source_Unit (Sloc (E2))))
4958 -- Entity must exist because predefined unit is correct
4960 raise Program_Error;
4969 -- Come here with E set to the first immediately visible entity on
4970 -- the homonym chain. This is the one we want unless there is another
4971 -- immediately visible entity further on in the chain for an inner
4972 -- scope (RM 8.3(8)).
4974 <<Immediately_Visible_Entity>> declare
4979 -- Find scope level of initial entity. When compiling through
4980 -- Rtsfind, the previous context is not completely invisible, and
4981 -- an outer entity may appear on the chain, whose scope is below
4982 -- the entry for Standard that delimits the current scope stack.
4983 -- Indicate that the level for this spurious entry is outside of
4984 -- the current scope stack.
4986 Level := Scope_Stack.Last;
4988 Scop := Scope_Stack.Table (Level).Entity;
4989 exit when Scop = Scope (E);
4991 exit when Scop = Standard_Standard;
4994 -- Now search remainder of homonym chain for more inner entry
4995 -- If the entity is Standard itself, it has no scope, and we
4996 -- compare it with the stack entry directly.
4999 while Present (E2) loop
5000 if Is_Immediately_Visible (E2) then
5002 -- If a generic package contains a local declaration that
5003 -- has the same name as the generic, there may be a visibility
5004 -- conflict in an instance, where the local declaration must
5005 -- also hide the name of the corresponding package renaming.
5006 -- We check explicitly for a package declared by a renaming,
5007 -- whose renamed entity is an instance that is on the scope
5008 -- stack, and that contains a homonym in the same scope. Once
5009 -- we have found it, we know that the package renaming is not
5010 -- immediately visible, and that the identifier denotes the
5011 -- other entity (and its homonyms if overloaded).
5013 if Scope (E) = Scope (E2)
5014 and then Ekind (E) = E_Package
5015 and then Present (Renamed_Object (E))
5016 and then Is_Generic_Instance (Renamed_Object (E))
5017 and then In_Open_Scopes (Renamed_Object (E))
5018 and then Comes_From_Source (N)
5020 Set_Is_Immediately_Visible (E, False);
5024 for J in Level + 1 .. Scope_Stack.Last loop
5025 if Scope_Stack.Table (J).Entity = Scope (E2)
5026 or else Scope_Stack.Table (J).Entity = E2
5039 -- At the end of that loop, E is the innermost immediately
5040 -- visible entity, so we are all set.
5043 -- Come here with entity found, and stored in E
5047 -- Check violation of No_Wide_Characters restriction
5049 Check_Wide_Character_Restriction (E, N);
5051 -- When distribution features are available (Get_PCS_Name /=
5052 -- Name_No_DSA), a remote access-to-subprogram type is converted
5053 -- into a record type holding whatever information is needed to
5054 -- perform a remote call on an RCI subprogram. In that case we
5055 -- rewrite any occurrence of the RAS type into the equivalent record
5056 -- type here. 'Access attribute references and RAS dereferences are
5057 -- then implemented using specific TSSs. However when distribution is
5058 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5059 -- generation of these TSSs, and we must keep the RAS type in its
5060 -- original access-to-subprogram form (since all calls through a
5061 -- value of such type will be local anyway in the absence of a PCS).
5063 if Comes_From_Source (N)
5064 and then Is_Remote_Access_To_Subprogram_Type (E)
5065 and then Ekind (E) = E_Access_Subprogram_Type
5066 and then Expander_Active
5067 and then Get_PCS_Name /= Name_No_DSA
5070 New_Occurrence_Of (Equivalent_Type (E), Sloc (N)));
5074 -- Set the entity. Note that the reason we call Set_Entity for the
5075 -- overloadable case, as opposed to Set_Entity_With_Checks is
5076 -- that in the overloaded case, the initial call can set the wrong
5077 -- homonym. The call that sets the right homonym is in Sem_Res and
5078 -- that call does use Set_Entity_With_Checks, so we don't miss
5081 if Is_Overloadable (E) then
5084 Set_Entity_With_Checks (N, E);
5090 Set_Etype (N, Get_Full_View (Etype (E)));
5093 if Debug_Flag_E then
5094 Write_Str (" found ");
5095 Write_Entity_Info (E, " ");
5098 -- If the Ekind of the entity is Void, it means that all homonyms
5099 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5100 -- test is skipped if the current scope is a record and the name is
5101 -- a pragma argument expression (case of Atomic and Volatile pragmas
5102 -- and possibly other similar pragmas added later, which are allowed
5103 -- to reference components in the current record).
5105 if Ekind (E) = E_Void
5107 (not Is_Record_Type (Current_Scope)
5108 or else Nkind (Parent (N)) /= N_Pragma_Argument_Association)
5110 Premature_Usage (N);
5112 -- If the entity is overloadable, collect all interpretations of the
5113 -- name for subsequent overload resolution. We optimize a bit here to
5114 -- do this only if we have an overloadable entity that is not on its
5115 -- own on the homonym chain.
5117 elsif Is_Overloadable (E)
5118 and then (Present (Homonym (E)) or else Current_Entity (N) /= E)
5120 Collect_Interps (N);
5122 -- If no homonyms were visible, the entity is unambiguous
5124 if not Is_Overloaded (N) then
5125 if not Is_Actual_Parameter then
5126 Generate_Reference (E, N);
5130 -- Case of non-overloadable entity, set the entity providing that
5131 -- we do not have the case of a discriminant reference within a
5132 -- default expression. Such references are replaced with the
5133 -- corresponding discriminal, which is the formal corresponding to
5134 -- to the discriminant in the initialization procedure.
5137 -- Entity is unambiguous, indicate that it is referenced here
5139 -- For a renaming of an object, always generate simple reference,
5140 -- we don't try to keep track of assignments in this case, except
5141 -- in SPARK mode where renamings are traversed for generating
5142 -- local effects of subprograms.
5145 and then Present (Renamed_Object (E))
5146 and then not GNATprove_Mode
5148 Generate_Reference (E, N);
5150 -- If the renamed entity is a private protected component,
5151 -- reference the original component as well. This needs to be
5152 -- done because the private renamings are installed before any
5153 -- analysis has occurred. Reference to a private component will
5154 -- resolve to the renaming and the original component will be
5155 -- left unreferenced, hence the following.
5157 if Is_Prival (E) then
5158 Generate_Reference (Prival_Link (E), N);
5161 -- One odd case is that we do not want to set the Referenced flag
5162 -- if the entity is a label, and the identifier is the label in
5163 -- the source, since this is not a reference from the point of
5164 -- view of the user.
5166 elsif Nkind (Parent (N)) = N_Label then
5168 R : constant Boolean := Referenced (E);
5171 -- Generate reference unless this is an actual parameter
5172 -- (see comment below)
5174 if Is_Actual_Parameter then
5175 Generate_Reference (E, N);
5176 Set_Referenced (E, R);
5180 -- Normal case, not a label: generate reference
5183 if not Is_Actual_Parameter then
5185 -- Package or generic package is always a simple reference
5187 if Ekind_In (E, E_Package, E_Generic_Package) then
5188 Generate_Reference (E, N, 'r');
5190 -- Else see if we have a left hand side
5195 Generate_Reference (E, N, 'm');
5198 Generate_Reference (E, N, 'r');
5200 -- If we don't know now, generate reference later
5203 Deferred_References.Append ((E, N));
5208 Check_Nested_Access (E);
5211 Set_Entity_Or_Discriminal (N, E);
5213 -- The name may designate a generalized reference, in which case
5214 -- the dereference interpretation will be included.
5216 if Ada_Version >= Ada_2012
5218 (Nkind (Parent (N)) in N_Subexpr
5219 or else Nkind_In (Parent (N), N_Object_Declaration,
5220 N_Assignment_Statement))
5222 Check_Implicit_Dereference (N, Etype (E));
5226 end Find_Direct_Name;
5228 ------------------------
5229 -- Find_Expanded_Name --
5230 ------------------------
5232 -- This routine searches the homonym chain of the entity until it finds
5233 -- an entity declared in the scope denoted by the prefix. If the entity
5234 -- is private, it may nevertheless be immediately visible, if we are in
5235 -- the scope of its declaration.
5237 procedure Find_Expanded_Name (N : Node_Id) is
5238 function In_Pragmas_Depends_Or_Global (N : Node_Id) return Boolean;
5239 -- Determine whether an arbitrary node N appears in pragmas [Refined_]
5240 -- Depends or [Refined_]Global.
5242 ----------------------------------
5243 -- In_Pragmas_Depends_Or_Global --
5244 ----------------------------------
5246 function In_Pragmas_Depends_Or_Global (N : Node_Id) return Boolean is
5250 -- Climb the parent chain looking for a pragma
5253 while Present (Par) loop
5254 if Nkind (Par) = N_Pragma
5255 and then Nam_In (Pragma_Name (Par), Name_Depends,
5257 Name_Refined_Depends,
5258 Name_Refined_Global)
5262 -- Prevent the search from going too far
5264 elsif Is_Body_Or_Package_Declaration (Par) then
5268 Par := Parent (Par);
5272 end In_Pragmas_Depends_Or_Global;
5276 Selector : constant Node_Id := Selector_Name (N);
5277 Candidate : Entity_Id := Empty;
5281 -- Start of processing for Find_Expanded_Name
5284 P_Name := Entity (Prefix (N));
5286 -- If the prefix is a renamed package, look for the entity in the
5287 -- original package.
5289 if Ekind (P_Name) = E_Package
5290 and then Present (Renamed_Object (P_Name))
5292 P_Name := Renamed_Object (P_Name);
5294 -- Rewrite node with entity field pointing to renamed object
5296 Rewrite (Prefix (N), New_Copy (Prefix (N)));
5297 Set_Entity (Prefix (N), P_Name);
5299 -- If the prefix is an object of a concurrent type, look for
5300 -- the entity in the associated task or protected type.
5302 elsif Is_Concurrent_Type (Etype (P_Name)) then
5303 P_Name := Etype (P_Name);
5306 Id := Current_Entity (Selector);
5309 Is_New_Candidate : Boolean;
5312 while Present (Id) loop
5313 if Scope (Id) = P_Name then
5315 Is_New_Candidate := True;
5317 -- Handle abstract views of states and variables. These are
5318 -- acceptable only when the reference to the view appears in
5319 -- pragmas [Refined_]Depends and [Refined_]Global.
5321 if Ekind (Id) = E_Abstract_State
5322 and then From_Limited_With (Id)
5323 and then Present (Non_Limited_View (Id))
5325 if In_Pragmas_Depends_Or_Global (N) then
5326 Candidate := Non_Limited_View (Id);
5327 Is_New_Candidate := True;
5329 -- Hide candidate because it is not used in a proper context
5333 Is_New_Candidate := False;
5337 -- Ada 2005 (AI-217): Handle shadow entities associated with types
5338 -- declared in limited-withed nested packages. We don't need to
5339 -- handle E_Incomplete_Subtype entities because the entities in
5340 -- the limited view are always E_Incomplete_Type entities (see
5341 -- Build_Limited_Views). Regarding the expression used to evaluate
5342 -- the scope, it is important to note that the limited view also
5343 -- has shadow entities associated nested packages. For this reason
5344 -- the correct scope of the entity is the scope of the real entity
5345 -- The non-limited view may itself be incomplete, in which case
5346 -- get the full view if available.
5348 elsif Ekind (Id) = E_Incomplete_Type
5349 and then From_Limited_With (Id)
5350 and then Present (Non_Limited_View (Id))
5351 and then Scope (Non_Limited_View (Id)) = P_Name
5353 Candidate := Get_Full_View (Non_Limited_View (Id));
5354 Is_New_Candidate := True;
5357 Is_New_Candidate := False;
5360 if Is_New_Candidate then
5361 if Is_Child_Unit (Id) or else P_Name = Standard_Standard then
5362 exit when Is_Visible_Lib_Unit (Id);
5364 exit when not Is_Hidden (Id);
5367 exit when Is_Immediately_Visible (Id);
5375 and then Ekind_In (P_Name, E_Procedure, E_Function)
5376 and then Is_Generic_Instance (P_Name)
5378 -- Expanded name denotes entity in (instance of) generic subprogram.
5379 -- The entity may be in the subprogram instance, or may denote one of
5380 -- the formals, which is declared in the enclosing wrapper package.
5382 P_Name := Scope (P_Name);
5384 Id := Current_Entity (Selector);
5385 while Present (Id) loop
5386 exit when Scope (Id) = P_Name;
5391 if No (Id) or else Chars (Id) /= Chars (Selector) then
5392 Set_Etype (N, Any_Type);
5394 -- If we are looking for an entity defined in System, try to find it
5395 -- in the child package that may have been provided as an extension
5396 -- to System. The Extend_System pragma will have supplied the name of
5397 -- the extension, which may have to be loaded.
5399 if Chars (P_Name) = Name_System
5400 and then Scope (P_Name) = Standard_Standard
5401 and then Present (System_Extend_Unit)
5402 and then Present_System_Aux (N)
5404 Set_Entity (Prefix (N), System_Aux_Id);
5405 Find_Expanded_Name (N);
5408 elsif Nkind (Selector) = N_Operator_Symbol
5409 and then Has_Implicit_Operator (N)
5411 -- There is an implicit instance of the predefined operator in
5412 -- the given scope. The operator entity is defined in Standard.
5413 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5417 elsif Nkind (Selector) = N_Character_Literal
5418 and then Has_Implicit_Character_Literal (N)
5420 -- If there is no literal defined in the scope denoted by the
5421 -- prefix, the literal may belong to (a type derived from)
5422 -- Standard_Character, for which we have no explicit literals.
5427 -- If the prefix is a single concurrent object, use its name in
5428 -- the error message, rather than that of the anonymous type.
5430 if Is_Concurrent_Type (P_Name)
5431 and then Is_Internal_Name (Chars (P_Name))
5433 Error_Msg_Node_2 := Entity (Prefix (N));
5435 Error_Msg_Node_2 := P_Name;
5438 if P_Name = System_Aux_Id then
5439 P_Name := Scope (P_Name);
5440 Set_Entity (Prefix (N), P_Name);
5443 if Present (Candidate) then
5445 -- If we know that the unit is a child unit we can give a more
5446 -- accurate error message.
5448 if Is_Child_Unit (Candidate) then
5450 -- If the candidate is a private child unit and we are in
5451 -- the visible part of a public unit, specialize the error
5452 -- message. There might be a private with_clause for it,
5453 -- but it is not currently active.
5455 if Is_Private_Descendant (Candidate)
5456 and then Ekind (Current_Scope) = E_Package
5457 and then not In_Private_Part (Current_Scope)
5458 and then not Is_Private_Descendant (Current_Scope)
5460 Error_Msg_N ("private child unit& is not visible here",
5463 -- Normal case where we have a missing with for a child unit
5466 Error_Msg_Qual_Level := 99;
5467 Error_Msg_NE -- CODEFIX
5468 ("missing `WITH &;`", Selector, Candidate);
5469 Error_Msg_Qual_Level := 0;
5472 -- Here we don't know that this is a child unit
5475 Error_Msg_NE ("& is not a visible entity of&", N, Selector);
5479 -- Within the instantiation of a child unit, the prefix may
5480 -- denote the parent instance, but the selector has the name
5481 -- of the original child. That is to say, when A.B appears
5482 -- within an instantiation of generic child unit B, the scope
5483 -- stack includes an instance of A (P_Name) and an instance
5484 -- of B under some other name. We scan the scope to find this
5485 -- child instance, which is the desired entity.
5486 -- Note that the parent may itself be a child instance, if
5487 -- the reference is of the form A.B.C, in which case A.B has
5488 -- already been rewritten with the proper entity.
5490 if In_Open_Scopes (P_Name)
5491 and then Is_Generic_Instance (P_Name)
5494 Gen_Par : constant Entity_Id :=
5495 Generic_Parent (Specification
5496 (Unit_Declaration_Node (P_Name)));
5497 S : Entity_Id := Current_Scope;
5501 for J in reverse 0 .. Scope_Stack.Last loop
5502 S := Scope_Stack.Table (J).Entity;
5504 exit when S = Standard_Standard;
5506 if Ekind_In (S, E_Function,
5510 P := Generic_Parent (Specification
5511 (Unit_Declaration_Node (S)));
5513 -- Check that P is a generic child of the generic
5514 -- parent of the prefix.
5517 and then Chars (P) = Chars (Selector)
5518 and then Scope (P) = Gen_Par
5529 -- If this is a selection from Ada, System or Interfaces, then
5530 -- we assume a missing with for the corresponding package.
5532 if Is_Known_Unit (N) then
5533 if not Error_Posted (N) then
5534 Error_Msg_Node_2 := Selector;
5535 Error_Msg_N -- CODEFIX
5536 ("missing `WITH &.&;`", Prefix (N));
5539 -- If this is a selection from a dummy package, then suppress
5540 -- the error message, of course the entity is missing if the
5541 -- package is missing.
5543 elsif Sloc (Error_Msg_Node_2) = No_Location then
5546 -- Here we have the case of an undefined component
5550 -- The prefix may hide a homonym in the context that
5551 -- declares the desired entity. This error can use a
5552 -- specialized message.
5554 if In_Open_Scopes (P_Name) then
5556 H : constant Entity_Id := Homonym (P_Name);
5560 and then Is_Compilation_Unit (H)
5562 (Is_Immediately_Visible (H)
5563 or else Is_Visible_Lib_Unit (H))
5565 Id := First_Entity (H);
5566 while Present (Id) loop
5567 if Chars (Id) = Chars (Selector) then
5568 Error_Msg_Qual_Level := 99;
5569 Error_Msg_Name_1 := Chars (Selector);
5571 ("% not declared in&", N, P_Name);
5573 ("\use fully qualified name starting with "
5574 & "Standard to make& visible", N, H);
5575 Error_Msg_Qual_Level := 0;
5583 -- If not found, standard error message
5585 Error_Msg_NE ("& not declared in&", N, Selector);
5591 Error_Msg_NE ("& not declared in&", N, Selector);
5594 -- Check for misspelling of some entity in prefix
5596 Id := First_Entity (P_Name);
5597 while Present (Id) loop
5598 if Is_Bad_Spelling_Of (Chars (Id), Chars (Selector))
5599 and then not Is_Internal_Name (Chars (Id))
5601 Error_Msg_NE -- CODEFIX
5602 ("possible misspelling of&", Selector, Id);
5609 -- Specialize the message if this may be an instantiation
5610 -- of a child unit that was not mentioned in the context.
5612 if Nkind (Parent (N)) = N_Package_Instantiation
5613 and then Is_Generic_Instance (Entity (Prefix (N)))
5614 and then Is_Compilation_Unit
5615 (Generic_Parent (Parent (Entity (Prefix (N)))))
5617 Error_Msg_Node_2 := Selector;
5618 Error_Msg_N -- CODEFIX
5619 ("\missing `WITH &.&;`", Prefix (N));
5629 if Comes_From_Source (N)
5630 and then Is_Remote_Access_To_Subprogram_Type (Id)
5631 and then Ekind (Id) = E_Access_Subprogram_Type
5632 and then Present (Equivalent_Type (Id))
5634 -- If we are not actually generating distribution code (i.e. the
5635 -- current PCS is the dummy non-distributed version), then the
5636 -- Equivalent_Type will be missing, and Id should be treated as
5637 -- a regular access-to-subprogram type.
5639 Id := Equivalent_Type (Id);
5640 Set_Chars (Selector, Chars (Id));
5643 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
5645 if Ekind (P_Name) = E_Package and then From_Limited_With (P_Name) then
5646 if From_Limited_With (Id)
5647 or else Is_Type (Id)
5648 or else Ekind (Id) = E_Package
5653 ("limited withed package can only be used to access "
5654 & "incomplete types", N);
5658 if Is_Task_Type (P_Name)
5659 and then ((Ekind (Id) = E_Entry
5660 and then Nkind (Parent (N)) /= N_Attribute_Reference)
5662 (Ekind (Id) = E_Entry_Family
5664 Nkind (Parent (Parent (N))) /= N_Attribute_Reference))
5666 -- If both the task type and the entry are in scope, this may still
5667 -- be the expanded name of an entry formal.
5669 if In_Open_Scopes (Id)
5670 and then Nkind (Parent (N)) = N_Selected_Component
5675 -- It is an entry call after all, either to the current task
5676 -- (which will deadlock) or to an enclosing task.
5678 Analyze_Selected_Component (N);
5683 Change_Selected_Component_To_Expanded_Name (N);
5685 -- Set appropriate type
5687 if Is_Type (Id) then
5690 Set_Etype (N, Get_Full_View (Etype (Id)));
5693 -- Do style check and generate reference, but skip both steps if this
5694 -- entity has homonyms, since we may not have the right homonym set yet.
5695 -- The proper homonym will be set during the resolve phase.
5697 if Has_Homonym (Id) then
5701 Set_Entity_Or_Discriminal (N, Id);
5705 Generate_Reference (Id, N, 'm');
5707 Generate_Reference (Id, N, 'r');
5709 Deferred_References.Append ((Id, N));
5713 -- Check for violation of No_Wide_Characters
5715 Check_Wide_Character_Restriction (Id, N);
5717 -- If the Ekind of the entity is Void, it means that all homonyms are
5718 -- hidden from all visibility (RM 8.3(5,14-20)).
5720 if Ekind (Id) = E_Void then
5721 Premature_Usage (N);
5723 elsif Is_Overloadable (Id) and then Present (Homonym (Id)) then
5725 H : Entity_Id := Homonym (Id);
5728 while Present (H) loop
5729 if Scope (H) = Scope (Id)
5730 and then (not Is_Hidden (H)
5731 or else Is_Immediately_Visible (H))
5733 Collect_Interps (N);
5740 -- If an extension of System is present, collect possible explicit
5741 -- overloadings declared in the extension.
5743 if Chars (P_Name) = Name_System
5744 and then Scope (P_Name) = Standard_Standard
5745 and then Present (System_Extend_Unit)
5746 and then Present_System_Aux (N)
5748 H := Current_Entity (Id);
5750 while Present (H) loop
5751 if Scope (H) = System_Aux_Id then
5752 Add_One_Interp (N, H, Etype (H));
5761 if Nkind (Selector_Name (N)) = N_Operator_Symbol
5762 and then Scope (Id) /= Standard_Standard
5764 -- In addition to user-defined operators in the given scope, there
5765 -- may be an implicit instance of the predefined operator. The
5766 -- operator (defined in Standard) is found in Has_Implicit_Operator,
5767 -- and added to the interpretations. Procedure Add_One_Interp will
5768 -- determine which hides which.
5770 if Has_Implicit_Operator (N) then
5775 -- If there is a single interpretation for N we can generate a
5776 -- reference to the unique entity found.
5778 if Is_Overloadable (Id) and then not Is_Overloaded (N) then
5779 Generate_Reference (Id, N);
5781 end Find_Expanded_Name;
5783 -------------------------
5784 -- Find_Renamed_Entity --
5785 -------------------------
5787 function Find_Renamed_Entity
5791 Is_Actual : Boolean := False) return Entity_Id
5794 I1 : Interp_Index := 0; -- Suppress junk warnings
5800 function Is_Visible_Operation (Op : Entity_Id) return Boolean;
5801 -- If the renamed entity is an implicit operator, check whether it is
5802 -- visible because its operand type is properly visible. This check
5803 -- applies to explicit renamed entities that appear in the source in a
5804 -- renaming declaration or a formal subprogram instance, but not to
5805 -- default generic actuals with a name.
5807 function Report_Overload return Entity_Id;
5808 -- List possible interpretations, and specialize message in the
5809 -- case of a generic actual.
5811 function Within (Inner, Outer : Entity_Id) return Boolean;
5812 -- Determine whether a candidate subprogram is defined within the
5813 -- enclosing instance. If yes, it has precedence over outer candidates.
5815 --------------------------
5816 -- Is_Visible_Operation --
5817 --------------------------
5819 function Is_Visible_Operation (Op : Entity_Id) return Boolean is
5825 if Ekind (Op) /= E_Operator
5826 or else Scope (Op) /= Standard_Standard
5827 or else (In_Instance
5828 and then (not Is_Actual
5829 or else Present (Enclosing_Instance)))
5834 -- For a fixed point type operator, check the resulting type,
5835 -- because it may be a mixed mode integer * fixed operation.
5837 if Present (Next_Formal (First_Formal (New_S)))
5838 and then Is_Fixed_Point_Type (Etype (New_S))
5840 Typ := Etype (New_S);
5842 Typ := Etype (First_Formal (New_S));
5845 Btyp := Base_Type (Typ);
5847 if Nkind (Nam) /= N_Expanded_Name then
5848 return (In_Open_Scopes (Scope (Btyp))
5849 or else Is_Potentially_Use_Visible (Btyp)
5850 or else In_Use (Btyp)
5851 or else In_Use (Scope (Btyp)));
5854 Scop := Entity (Prefix (Nam));
5856 if Ekind (Scop) = E_Package
5857 and then Present (Renamed_Object (Scop))
5859 Scop := Renamed_Object (Scop);
5862 -- Operator is visible if prefix of expanded name denotes
5863 -- scope of type, or else type is defined in System_Aux
5864 -- and the prefix denotes System.
5866 return Scope (Btyp) = Scop
5867 or else (Scope (Btyp) = System_Aux_Id
5868 and then Scope (Scope (Btyp)) = Scop);
5871 end Is_Visible_Operation;
5877 function Within (Inner, Outer : Entity_Id) return Boolean is
5881 Sc := Scope (Inner);
5882 while Sc /= Standard_Standard loop
5893 ---------------------
5894 -- Report_Overload --
5895 ---------------------
5897 function Report_Overload return Entity_Id is
5900 Error_Msg_NE -- CODEFIX
5901 ("ambiguous actual subprogram&, " &
5902 "possible interpretations:", N, Nam);
5904 Error_Msg_N -- CODEFIX
5905 ("ambiguous subprogram, " &
5906 "possible interpretations:", N);
5909 List_Interps (Nam, N);
5911 end Report_Overload;
5913 -- Start of processing for Find_Renamed_Entity
5917 Candidate_Renaming := Empty;
5919 if not Is_Overloaded (Nam) then
5920 if Is_Actual and then Present (Enclosing_Instance) then
5921 Old_S := Entity (Nam);
5923 elsif Entity_Matches_Spec (Entity (Nam), New_S) then
5924 Candidate_Renaming := New_S;
5926 if Is_Visible_Operation (Entity (Nam)) then
5927 Old_S := Entity (Nam);
5931 Present (First_Formal (Entity (Nam)))
5932 and then Present (First_Formal (New_S))
5933 and then (Base_Type (Etype (First_Formal (Entity (Nam)))) =
5934 Base_Type (Etype (First_Formal (New_S))))
5936 Candidate_Renaming := Entity (Nam);
5940 Get_First_Interp (Nam, Ind, It);
5941 while Present (It.Nam) loop
5942 if Entity_Matches_Spec (It.Nam, New_S)
5943 and then Is_Visible_Operation (It.Nam)
5945 if Old_S /= Any_Id then
5947 -- Note: The call to Disambiguate only happens if a
5948 -- previous interpretation was found, in which case I1
5949 -- has received a value.
5951 It1 := Disambiguate (Nam, I1, Ind, Etype (Old_S));
5953 if It1 = No_Interp then
5954 Inst := Enclosing_Instance;
5956 if Present (Inst) then
5957 if Within (It.Nam, Inst) then
5958 if Within (Old_S, Inst) then
5960 -- Choose the innermost subprogram, which would
5961 -- have hidden the outer one in the generic.
5963 if Scope_Depth (It.Nam) <
5972 elsif Within (Old_S, Inst) then
5976 return Report_Overload;
5979 -- If not within an instance, ambiguity is real
5982 return Report_Overload;
5996 Present (First_Formal (It.Nam))
5997 and then Present (First_Formal (New_S))
5998 and then (Base_Type (Etype (First_Formal (It.Nam))) =
5999 Base_Type (Etype (First_Formal (New_S))))
6001 Candidate_Renaming := It.Nam;
6004 Get_Next_Interp (Ind, It);
6007 Set_Entity (Nam, Old_S);
6009 if Old_S /= Any_Id then
6010 Set_Is_Overloaded (Nam, False);
6015 end Find_Renamed_Entity;
6017 -----------------------------
6018 -- Find_Selected_Component --
6019 -----------------------------
6021 procedure Find_Selected_Component (N : Node_Id) is
6022 P : constant Node_Id := Prefix (N);
6025 -- Entity denoted by prefix
6032 function Is_Reference_In_Subunit return Boolean;
6033 -- In a subunit, the scope depth is not a proper measure of hiding,
6034 -- because the context of the proper body may itself hide entities in
6035 -- parent units. This rare case requires inspecting the tree directly
6036 -- because the proper body is inserted in the main unit and its context
6037 -- is simply added to that of the parent.
6039 -----------------------------
6040 -- Is_Reference_In_Subunit --
6041 -----------------------------
6043 function Is_Reference_In_Subunit return Boolean is
6045 Comp_Unit : Node_Id;
6049 while Present (Comp_Unit)
6050 and then Nkind (Comp_Unit) /= N_Compilation_Unit
6052 Comp_Unit := Parent (Comp_Unit);
6055 if No (Comp_Unit) or else Nkind (Unit (Comp_Unit)) /= N_Subunit then
6059 -- Now check whether the package is in the context of the subunit
6061 Clause := First (Context_Items (Comp_Unit));
6062 while Present (Clause) loop
6063 if Nkind (Clause) = N_With_Clause
6064 and then Entity (Name (Clause)) = P_Name
6069 Clause := Next (Clause);
6073 end Is_Reference_In_Subunit;
6075 -- Start of processing for Find_Selected_Component
6080 if Nkind (P) = N_Error then
6084 -- Selector name cannot be a character literal or an operator symbol in
6085 -- SPARK, except for the operator symbol in a renaming.
6087 if Restriction_Check_Required (SPARK_05) then
6088 if Nkind (Selector_Name (N)) = N_Character_Literal then
6089 Check_SPARK_Restriction
6090 ("character literal cannot be prefixed", N);
6091 elsif Nkind (Selector_Name (N)) = N_Operator_Symbol
6092 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
6094 Check_SPARK_Restriction ("operator symbol cannot be prefixed", N);
6098 -- If the selector already has an entity, the node has been constructed
6099 -- in the course of expansion, and is known to be valid. Do not verify
6100 -- that it is defined for the type (it may be a private component used
6101 -- in the expansion of record equality).
6103 if Present (Entity (Selector_Name (N))) then
6104 if No (Etype (N)) or else Etype (N) = Any_Type then
6106 Sel_Name : constant Node_Id := Selector_Name (N);
6107 Selector : constant Entity_Id := Entity (Sel_Name);
6111 Set_Etype (Sel_Name, Etype (Selector));
6113 if not Is_Entity_Name (P) then
6117 -- Build an actual subtype except for the first parameter
6118 -- of an init proc, where this actual subtype is by
6119 -- definition incorrect, since the object is uninitialized
6120 -- (and does not even have defined discriminants etc.)
6122 if Is_Entity_Name (P)
6123 and then Ekind (Entity (P)) = E_Function
6125 Nam := New_Copy (P);
6127 if Is_Overloaded (P) then
6128 Save_Interps (P, Nam);
6131 Rewrite (P, Make_Function_Call (Sloc (P), Name => Nam));
6133 Analyze_Selected_Component (N);
6136 elsif Ekind (Selector) = E_Component
6137 and then (not Is_Entity_Name (P)
6138 or else Chars (Entity (P)) /= Name_uInit)
6140 -- Do not build the subtype when referencing components of
6141 -- dispatch table wrappers. Required to avoid generating
6142 -- elaboration code with HI runtimes. JVM and .NET use a
6143 -- modified version of Ada.Tags which does not contain RE_
6144 -- Dispatch_Table_Wrapper and RE_No_Dispatch_Table_Wrapper.
6145 -- Avoid raising RE_Not_Available exception in those cases.
6147 if VM_Target = No_VM
6148 and then RTU_Loaded (Ada_Tags)
6150 ((RTE_Available (RE_Dispatch_Table_Wrapper)
6151 and then Scope (Selector) =
6152 RTE (RE_Dispatch_Table_Wrapper))
6154 (RTE_Available (RE_No_Dispatch_Table_Wrapper)
6155 and then Scope (Selector) =
6156 RTE (RE_No_Dispatch_Table_Wrapper)))
6161 Build_Actual_Subtype_Of_Component
6162 (Etype (Selector), N);
6169 if No (C_Etype) then
6170 C_Etype := Etype (Selector);
6172 Insert_Action (N, C_Etype);
6173 C_Etype := Defining_Identifier (C_Etype);
6176 Set_Etype (N, C_Etype);
6179 -- If this is the name of an entry or protected operation, and
6180 -- the prefix is an access type, insert an explicit dereference,
6181 -- so that entry calls are treated uniformly.
6183 if Is_Access_Type (Etype (P))
6184 and then Is_Concurrent_Type (Designated_Type (Etype (P)))
6187 New_P : constant Node_Id :=
6188 Make_Explicit_Dereference (Sloc (P),
6189 Prefix => Relocate_Node (P));
6192 Set_Etype (P, Designated_Type (Etype (Prefix (P))));
6196 -- If the selected component appears within a default expression
6197 -- and it has an actual subtype, the pre-analysis has not yet
6198 -- completed its analysis, because Insert_Actions is disabled in
6199 -- that context. Within the init proc of the enclosing type we
6200 -- must complete this analysis, if an actual subtype was created.
6202 elsif Inside_Init_Proc then
6204 Typ : constant Entity_Id := Etype (N);
6205 Decl : constant Node_Id := Declaration_Node (Typ);
6207 if Nkind (Decl) = N_Subtype_Declaration
6208 and then not Analyzed (Decl)
6209 and then Is_List_Member (Decl)
6210 and then No (Parent (Decl))
6213 Insert_Action (N, Decl);
6220 elsif Is_Entity_Name (P) then
6221 P_Name := Entity (P);
6223 -- The prefix may denote an enclosing type which is the completion
6224 -- of an incomplete type declaration.
6226 if Is_Type (P_Name) then
6227 Set_Entity (P, Get_Full_View (P_Name));
6228 Set_Etype (P, Entity (P));
6229 P_Name := Entity (P);
6232 P_Type := Base_Type (Etype (P));
6234 if Debug_Flag_E then
6235 Write_Str ("Found prefix type to be ");
6236 Write_Entity_Info (P_Type, " "); Write_Eol;
6239 -- First check for components of a record object (not the
6240 -- result of a call, which is handled below).
6242 if Is_Appropriate_For_Record (P_Type)
6243 and then not Is_Overloadable (P_Name)
6244 and then not Is_Type (P_Name)
6246 -- Selected component of record. Type checking will validate
6247 -- name of selector.
6249 -- ??? Could we rewrite an implicit dereference into an explicit
6252 Analyze_Selected_Component (N);
6254 -- Reference to type name in predicate/invariant expression
6256 elsif Is_Appropriate_For_Entry_Prefix (P_Type)
6257 and then not In_Open_Scopes (P_Name)
6258 and then (not Is_Concurrent_Type (Etype (P_Name))
6259 or else not In_Open_Scopes (Etype (P_Name)))
6261 -- Call to protected operation or entry. Type checking is
6262 -- needed on the prefix.
6264 Analyze_Selected_Component (N);
6266 elsif (In_Open_Scopes (P_Name)
6267 and then Ekind (P_Name) /= E_Void
6268 and then not Is_Overloadable (P_Name))
6269 or else (Is_Concurrent_Type (Etype (P_Name))
6270 and then In_Open_Scopes (Etype (P_Name)))
6272 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6273 -- enclosing construct that is not a subprogram or accept.
6275 Find_Expanded_Name (N);
6277 elsif Ekind (P_Name) = E_Package then
6278 Find_Expanded_Name (N);
6280 elsif Is_Overloadable (P_Name) then
6282 -- The subprogram may be a renaming (of an enclosing scope) as
6283 -- in the case of the name of the generic within an instantiation.
6285 if Ekind_In (P_Name, E_Procedure, E_Function)
6286 and then Present (Alias (P_Name))
6287 and then Is_Generic_Instance (Alias (P_Name))
6289 P_Name := Alias (P_Name);
6292 if Is_Overloaded (P) then
6294 -- The prefix must resolve to a unique enclosing construct
6297 Found : Boolean := False;
6302 Get_First_Interp (P, Ind, It);
6303 while Present (It.Nam) loop
6304 if In_Open_Scopes (It.Nam) then
6307 "prefix must be unique enclosing scope", N);
6308 Set_Entity (N, Any_Id);
6309 Set_Etype (N, Any_Type);
6318 Get_Next_Interp (Ind, It);
6323 if In_Open_Scopes (P_Name) then
6324 Set_Entity (P, P_Name);
6325 Set_Is_Overloaded (P, False);
6326 Find_Expanded_Name (N);
6329 -- If no interpretation as an expanded name is possible, it
6330 -- must be a selected component of a record returned by a
6331 -- function call. Reformat prefix as a function call, the rest
6332 -- is done by type resolution.
6334 -- Error if the prefix is procedure or entry, as is P.X
6336 if Ekind (P_Name) /= E_Function
6338 (not Is_Overloaded (P)
6339 or else Nkind (Parent (N)) = N_Procedure_Call_Statement)
6341 -- Prefix may mention a package that is hidden by a local
6342 -- declaration: let the user know. Scan the full homonym
6343 -- chain, the candidate package may be anywhere on it.
6345 if Present (Homonym (Current_Entity (P_Name))) then
6346 P_Name := Current_Entity (P_Name);
6348 while Present (P_Name) loop
6349 exit when Ekind (P_Name) = E_Package;
6350 P_Name := Homonym (P_Name);
6353 if Present (P_Name) then
6354 if not Is_Reference_In_Subunit then
6355 Error_Msg_Sloc := Sloc (Entity (Prefix (N)));
6357 ("package& is hidden by declaration#", N, P_Name);
6360 Set_Entity (Prefix (N), P_Name);
6361 Find_Expanded_Name (N);
6365 P_Name := Entity (Prefix (N));
6370 ("invalid prefix in selected component&", N, P_Name);
6371 Change_Selected_Component_To_Expanded_Name (N);
6372 Set_Entity (N, Any_Id);
6373 Set_Etype (N, Any_Type);
6375 -- Here we have a function call, so do the reformatting
6378 Nam := New_Copy (P);
6379 Save_Interps (P, Nam);
6381 -- We use Replace here because this is one of those cases
6382 -- where the parser has missclassified the node, and we
6383 -- fix things up and then do the semantic analysis on the
6384 -- fixed up node. Normally we do this using one of the
6385 -- Sinfo.CN routines, but this is too tricky for that.
6387 -- Note that using Rewrite would be wrong, because we
6388 -- would have a tree where the original node is unanalyzed,
6389 -- and this violates the required interface for ASIS.
6392 Make_Function_Call (Sloc (P), Name => Nam));
6394 -- Now analyze the reformatted node
6397 Analyze_Selected_Component (N);
6401 -- Remaining cases generate various error messages
6404 -- Format node as expanded name, to avoid cascaded errors
6406 Change_Selected_Component_To_Expanded_Name (N);
6407 Set_Entity (N, Any_Id);
6408 Set_Etype (N, Any_Type);
6410 -- Issue error message, but avoid this if error issued already.
6411 -- Use identifier of prefix if one is available.
6413 if P_Name = Any_Id then
6416 elsif Ekind (P_Name) = E_Void then
6417 Premature_Usage (P);
6419 elsif Nkind (P) /= N_Attribute_Reference then
6421 "invalid prefix in selected component&", P);
6423 if Is_Access_Type (P_Type)
6424 and then Ekind (Designated_Type (P_Type)) = E_Incomplete_Type
6427 ("\dereference must not be of an incomplete type " &
6433 "invalid prefix in selected component", P);
6437 -- Selector name is restricted in SPARK
6439 if Nkind (N) = N_Expanded_Name
6440 and then Restriction_Check_Required (SPARK_05)
6442 if Is_Subprogram (P_Name) then
6443 Check_SPARK_Restriction
6444 ("prefix of expanded name cannot be a subprogram", P);
6445 elsif Ekind (P_Name) = E_Loop then
6446 Check_SPARK_Restriction
6447 ("prefix of expanded name cannot be a loop statement", P);
6452 -- If prefix is not the name of an entity, it must be an expression,
6453 -- whose type is appropriate for a record. This is determined by
6456 Analyze_Selected_Component (N);
6459 Analyze_Dimension (N);
6460 end Find_Selected_Component;
6466 procedure Find_Type (N : Node_Id) is
6476 elsif Nkind (N) = N_Attribute_Reference then
6478 -- Class attribute. This is not valid in Ada 83 mode, but we do not
6479 -- need to enforce that at this point, since the declaration of the
6480 -- tagged type in the prefix would have been flagged already.
6482 if Attribute_Name (N) = Name_Class then
6483 Check_Restriction (No_Dispatch, N);
6484 Find_Type (Prefix (N));
6486 -- Propagate error from bad prefix
6488 if Etype (Prefix (N)) = Any_Type then
6489 Set_Entity (N, Any_Type);
6490 Set_Etype (N, Any_Type);
6494 T := Base_Type (Entity (Prefix (N)));
6496 -- Case where type is not known to be tagged. Its appearance in
6497 -- the prefix of the 'Class attribute indicates that the full view
6500 if not Is_Tagged_Type (T) then
6501 if Ekind (T) = E_Incomplete_Type then
6503 -- It is legal to denote the class type of an incomplete
6504 -- type. The full type will have to be tagged, of course.
6505 -- In Ada 2005 this usage is declared obsolescent, so we
6506 -- warn accordingly. This usage is only legal if the type
6507 -- is completed in the current scope, and not for a limited
6510 if Ada_Version >= Ada_2005 then
6512 -- Test whether the Available_View of a limited type view
6513 -- is tagged, since the limited view may not be marked as
6514 -- tagged if the type itself has an untagged incomplete
6515 -- type view in its package.
6517 if From_Limited_With (T)
6518 and then not Is_Tagged_Type (Available_View (T))
6521 ("prefix of Class attribute must be tagged", N);
6522 Set_Etype (N, Any_Type);
6523 Set_Entity (N, Any_Type);
6526 -- ??? This test is temporarily disabled (always
6527 -- False) because it causes an unwanted warning on
6528 -- GNAT sources (built with -gnatg, which includes
6529 -- Warn_On_Obsolescent_ Feature). Once this issue
6530 -- is cleared in the sources, it can be enabled.
6532 elsif Warn_On_Obsolescent_Feature and then False then
6534 ("applying 'Class to an untagged incomplete type"
6535 & " is an obsolescent feature (RM J.11)?r?", N);
6539 Set_Is_Tagged_Type (T);
6540 Set_Direct_Primitive_Operations (T, New_Elmt_List);
6541 Make_Class_Wide_Type (T);
6542 Set_Entity (N, Class_Wide_Type (T));
6543 Set_Etype (N, Class_Wide_Type (T));
6545 elsif Ekind (T) = E_Private_Type
6546 and then not Is_Generic_Type (T)
6547 and then In_Private_Part (Scope (T))
6549 -- The Class attribute can be applied to an untagged private
6550 -- type fulfilled by a tagged type prior to the full type
6551 -- declaration (but only within the parent package's private
6552 -- part). Create the class-wide type now and check that the
6553 -- full type is tagged later during its analysis. Note that
6554 -- we do not mark the private type as tagged, unlike the
6555 -- case of incomplete types, because the type must still
6556 -- appear untagged to outside units.
6558 if No (Class_Wide_Type (T)) then
6559 Make_Class_Wide_Type (T);
6562 Set_Entity (N, Class_Wide_Type (T));
6563 Set_Etype (N, Class_Wide_Type (T));
6566 -- Should we introduce a type Any_Tagged and use Wrong_Type
6567 -- here, it would be a bit more consistent???
6570 ("tagged type required, found}",
6571 Prefix (N), First_Subtype (T));
6572 Set_Entity (N, Any_Type);
6576 -- Case of tagged type
6579 if Is_Concurrent_Type (T) then
6580 if No (Corresponding_Record_Type (Entity (Prefix (N)))) then
6582 -- Previous error. Use current type, which at least
6583 -- provides some operations.
6585 C := Entity (Prefix (N));
6588 C := Class_Wide_Type
6589 (Corresponding_Record_Type (Entity (Prefix (N))));
6593 C := Class_Wide_Type (Entity (Prefix (N)));
6596 Set_Entity_With_Checks (N, C);
6597 Generate_Reference (C, N);
6601 -- Base attribute, not allowed in Ada 83
6603 elsif Attribute_Name (N) = Name_Base then
6604 Error_Msg_Name_1 := Name_Base;
6605 Check_SPARK_Restriction
6606 ("attribute% is only allowed as prefix of another attribute", N);
6608 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
6610 ("(Ada 83) Base attribute not allowed in subtype mark", N);
6613 Find_Type (Prefix (N));
6614 Typ := Entity (Prefix (N));
6616 if Ada_Version >= Ada_95
6617 and then not Is_Scalar_Type (Typ)
6618 and then not Is_Generic_Type (Typ)
6621 ("prefix of Base attribute must be scalar type",
6624 elsif Warn_On_Redundant_Constructs
6625 and then Base_Type (Typ) = Typ
6627 Error_Msg_NE -- CODEFIX
6628 ("redundant attribute, & is its own base type?r?", N, Typ);
6631 T := Base_Type (Typ);
6633 -- Rewrite attribute reference with type itself (see similar
6634 -- processing in Analyze_Attribute, case Base). Preserve prefix
6635 -- if present, for other legality checks.
6637 if Nkind (Prefix (N)) = N_Expanded_Name then
6639 Make_Expanded_Name (Sloc (N),
6641 Prefix => New_Copy (Prefix (Prefix (N))),
6642 Selector_Name => New_Occurrence_Of (T, Sloc (N))));
6645 Rewrite (N, New_Occurrence_Of (T, Sloc (N)));
6652 elsif Attribute_Name (N) = Name_Stub_Type then
6654 -- This is handled in Analyze_Attribute
6658 -- All other attributes are invalid in a subtype mark
6661 Error_Msg_N ("invalid attribute in subtype mark", N);
6667 if Is_Entity_Name (N) then
6668 T_Name := Entity (N);
6670 Error_Msg_N ("subtype mark required in this context", N);
6671 Set_Etype (N, Any_Type);
6675 if T_Name = Any_Id or else Etype (N) = Any_Type then
6677 -- Undefined id. Make it into a valid type
6679 Set_Entity (N, Any_Type);
6681 elsif not Is_Type (T_Name)
6682 and then T_Name /= Standard_Void_Type
6684 Error_Msg_Sloc := Sloc (T_Name);
6685 Error_Msg_N ("subtype mark required in this context", N);
6686 Error_Msg_NE ("\\found & declared#", N, T_Name);
6687 Set_Entity (N, Any_Type);
6690 -- If the type is an incomplete type created to handle
6691 -- anonymous access components of a record type, then the
6692 -- incomplete type is the visible entity and subsequent
6693 -- references will point to it. Mark the original full
6694 -- type as referenced, to prevent spurious warnings.
6696 if Is_Incomplete_Type (T_Name)
6697 and then Present (Full_View (T_Name))
6698 and then not Comes_From_Source (T_Name)
6700 Set_Referenced (Full_View (T_Name));
6703 T_Name := Get_Full_View (T_Name);
6705 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
6706 -- limited-with clauses
6708 if From_Limited_With (T_Name)
6709 and then Ekind (T_Name) in Incomplete_Kind
6710 and then Present (Non_Limited_View (T_Name))
6711 and then Is_Interface (Non_Limited_View (T_Name))
6713 T_Name := Non_Limited_View (T_Name);
6716 if In_Open_Scopes (T_Name) then
6717 if Ekind (Base_Type (T_Name)) = E_Task_Type then
6719 -- In Ada 2005, a task name can be used in an access
6720 -- definition within its own body. It cannot be used
6721 -- in the discriminant part of the task declaration,
6722 -- nor anywhere else in the declaration because entries
6723 -- cannot have access parameters.
6725 if Ada_Version >= Ada_2005
6726 and then Nkind (Parent (N)) = N_Access_Definition
6728 Set_Entity (N, T_Name);
6729 Set_Etype (N, T_Name);
6731 if Has_Completion (T_Name) then
6736 ("task type cannot be used as type mark " &
6737 "within its own declaration", N);
6742 ("task type cannot be used as type mark " &
6743 "within its own spec or body", N);
6746 elsif Ekind (Base_Type (T_Name)) = E_Protected_Type then
6748 -- In Ada 2005, a protected name can be used in an access
6749 -- definition within its own body.
6751 if Ada_Version >= Ada_2005
6752 and then Nkind (Parent (N)) = N_Access_Definition
6754 Set_Entity (N, T_Name);
6755 Set_Etype (N, T_Name);
6760 ("protected type cannot be used as type mark " &
6761 "within its own spec or body", N);
6765 Error_Msg_N ("type declaration cannot refer to itself", N);
6768 Set_Etype (N, Any_Type);
6769 Set_Entity (N, Any_Type);
6770 Set_Error_Posted (T_Name);
6774 Set_Entity (N, T_Name);
6775 Set_Etype (N, T_Name);
6779 if Present (Etype (N)) and then Comes_From_Source (N) then
6780 if Is_Fixed_Point_Type (Etype (N)) then
6781 Check_Restriction (No_Fixed_Point, N);
6782 elsif Is_Floating_Point_Type (Etype (N)) then
6783 Check_Restriction (No_Floating_Point, N);
6788 ------------------------------------
6789 -- Has_Implicit_Character_Literal --
6790 ------------------------------------
6792 function Has_Implicit_Character_Literal (N : Node_Id) return Boolean is
6794 Found : Boolean := False;
6795 P : constant Entity_Id := Entity (Prefix (N));
6796 Priv_Id : Entity_Id := Empty;
6799 if Ekind (P) = E_Package and then not In_Open_Scopes (P) then
6800 Priv_Id := First_Private_Entity (P);
6803 if P = Standard_Standard then
6804 Change_Selected_Component_To_Expanded_Name (N);
6805 Rewrite (N, Selector_Name (N));
6807 Set_Etype (Original_Node (N), Standard_Character);
6811 Id := First_Entity (P);
6812 while Present (Id) and then Id /= Priv_Id loop
6813 if Is_Standard_Character_Type (Id) and then Is_Base_Type (Id) then
6815 -- We replace the node with the literal itself, resolve as a
6816 -- character, and set the type correctly.
6819 Change_Selected_Component_To_Expanded_Name (N);
6820 Rewrite (N, Selector_Name (N));
6823 Set_Etype (Original_Node (N), Id);
6827 -- More than one type derived from Character in given scope.
6828 -- Collect all possible interpretations.
6830 Add_One_Interp (N, Id, Id);
6838 end Has_Implicit_Character_Literal;
6840 ----------------------
6841 -- Has_Private_With --
6842 ----------------------
6844 function Has_Private_With (E : Entity_Id) return Boolean is
6845 Comp_Unit : constant Node_Id := Cunit (Current_Sem_Unit);
6849 Item := First (Context_Items (Comp_Unit));
6850 while Present (Item) loop
6851 if Nkind (Item) = N_With_Clause
6852 and then Private_Present (Item)
6853 and then Entity (Name (Item)) = E
6862 end Has_Private_With;
6864 ---------------------------
6865 -- Has_Implicit_Operator --
6866 ---------------------------
6868 function Has_Implicit_Operator (N : Node_Id) return Boolean is
6869 Op_Id : constant Name_Id := Chars (Selector_Name (N));
6870 P : constant Entity_Id := Entity (Prefix (N));
6872 Priv_Id : Entity_Id := Empty;
6874 procedure Add_Implicit_Operator
6876 Op_Type : Entity_Id := Empty);
6877 -- Add implicit interpretation to node N, using the type for which a
6878 -- predefined operator exists. If the operator yields a boolean type,
6879 -- the Operand_Type is implicitly referenced by the operator, and a
6880 -- reference to it must be generated.
6882 ---------------------------
6883 -- Add_Implicit_Operator --
6884 ---------------------------
6886 procedure Add_Implicit_Operator
6888 Op_Type : Entity_Id := Empty)
6890 Predef_Op : Entity_Id;
6893 Predef_Op := Current_Entity (Selector_Name (N));
6894 while Present (Predef_Op)
6895 and then Scope (Predef_Op) /= Standard_Standard
6897 Predef_Op := Homonym (Predef_Op);
6900 if Nkind (N) = N_Selected_Component then
6901 Change_Selected_Component_To_Expanded_Name (N);
6904 -- If the context is an unanalyzed function call, determine whether
6905 -- a binary or unary interpretation is required.
6907 if Nkind (Parent (N)) = N_Indexed_Component then
6909 Is_Binary_Call : constant Boolean :=
6911 (Next (First (Expressions (Parent (N)))));
6912 Is_Binary_Op : constant Boolean :=
6914 (Predef_Op) /= Last_Entity (Predef_Op);
6915 Predef_Op2 : constant Entity_Id := Homonym (Predef_Op);
6918 if Is_Binary_Call then
6919 if Is_Binary_Op then
6920 Add_One_Interp (N, Predef_Op, T);
6922 Add_One_Interp (N, Predef_Op2, T);
6926 if not Is_Binary_Op then
6927 Add_One_Interp (N, Predef_Op, T);
6929 Add_One_Interp (N, Predef_Op2, T);
6935 Add_One_Interp (N, Predef_Op, T);
6937 -- For operators with unary and binary interpretations, if
6938 -- context is not a call, add both
6940 if Present (Homonym (Predef_Op)) then
6941 Add_One_Interp (N, Homonym (Predef_Op), T);
6945 -- The node is a reference to a predefined operator, and
6946 -- an implicit reference to the type of its operands.
6948 if Present (Op_Type) then
6949 Generate_Operator_Reference (N, Op_Type);
6951 Generate_Operator_Reference (N, T);
6953 end Add_Implicit_Operator;
6955 -- Start of processing for Has_Implicit_Operator
6958 if Ekind (P) = E_Package and then not In_Open_Scopes (P) then
6959 Priv_Id := First_Private_Entity (P);
6962 Id := First_Entity (P);
6966 -- Boolean operators: an implicit declaration exists if the scope
6967 -- contains a declaration for a derived Boolean type, or for an
6968 -- array of Boolean type.
6970 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor =>
6971 while Id /= Priv_Id loop
6972 if Valid_Boolean_Arg (Id) and then Is_Base_Type (Id) then
6973 Add_Implicit_Operator (Id);
6980 -- Equality: look for any non-limited type (result is Boolean)
6982 when Name_Op_Eq | Name_Op_Ne =>
6983 while Id /= Priv_Id loop
6985 and then not Is_Limited_Type (Id)
6986 and then Is_Base_Type (Id)
6988 Add_Implicit_Operator (Standard_Boolean, Id);
6995 -- Comparison operators: scalar type, or array of scalar
6997 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge =>
6998 while Id /= Priv_Id loop
6999 if (Is_Scalar_Type (Id)
7000 or else (Is_Array_Type (Id)
7001 and then Is_Scalar_Type (Component_Type (Id))))
7002 and then Is_Base_Type (Id)
7004 Add_Implicit_Operator (Standard_Boolean, Id);
7011 -- Arithmetic operators: any numeric type
7021 while Id /= Priv_Id loop
7022 if Is_Numeric_Type (Id) and then Is_Base_Type (Id) then
7023 Add_Implicit_Operator (Id);
7030 -- Concatenation: any one-dimensional array type
7032 when Name_Op_Concat =>
7033 while Id /= Priv_Id loop
7034 if Is_Array_Type (Id)
7035 and then Number_Dimensions (Id) = 1
7036 and then Is_Base_Type (Id)
7038 Add_Implicit_Operator (Id);
7045 -- What is the others condition here? Should we be using a
7046 -- subtype of Name_Id that would restrict to operators ???
7048 when others => null;
7051 -- If we fall through, then we do not have an implicit operator
7055 end Has_Implicit_Operator;
7057 -----------------------------------
7058 -- Has_Loop_In_Inner_Open_Scopes --
7059 -----------------------------------
7061 function Has_Loop_In_Inner_Open_Scopes (S : Entity_Id) return Boolean is
7063 -- Several scope stacks are maintained by Scope_Stack. The base of the
7064 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7065 -- flag in the scope stack entry. Note that the scope stacks used to
7066 -- simply be delimited implicitly by the presence of Standard_Standard
7067 -- at their base, but there now are cases where this is not sufficient
7068 -- because Standard_Standard actually may appear in the middle of the
7069 -- active set of scopes.
7071 for J in reverse 0 .. Scope_Stack.Last loop
7073 -- S was reached without seing a loop scope first
7075 if Scope_Stack.Table (J).Entity = S then
7078 -- S was not yet reached, so it contains at least one inner loop
7080 elsif Ekind (Scope_Stack.Table (J).Entity) = E_Loop then
7084 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7085 -- cases where Standard_Standard appears in the middle of the active
7086 -- set of scopes. This affects the declaration and overriding of
7087 -- private inherited operations in instantiations of generic child
7090 pragma Assert (not Scope_Stack.Table (J).Is_Active_Stack_Base);
7093 raise Program_Error; -- unreachable
7094 end Has_Loop_In_Inner_Open_Scopes;
7096 --------------------
7097 -- In_Open_Scopes --
7098 --------------------
7100 function In_Open_Scopes (S : Entity_Id) return Boolean is
7102 -- Several scope stacks are maintained by Scope_Stack. The base of the
7103 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7104 -- flag in the scope stack entry. Note that the scope stacks used to
7105 -- simply be delimited implicitly by the presence of Standard_Standard
7106 -- at their base, but there now are cases where this is not sufficient
7107 -- because Standard_Standard actually may appear in the middle of the
7108 -- active set of scopes.
7110 for J in reverse 0 .. Scope_Stack.Last loop
7111 if Scope_Stack.Table (J).Entity = S then
7115 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7116 -- cases where Standard_Standard appears in the middle of the active
7117 -- set of scopes. This affects the declaration and overriding of
7118 -- private inherited operations in instantiations of generic child
7121 exit when Scope_Stack.Table (J).Is_Active_Stack_Base;
7127 -----------------------------
7128 -- Inherit_Renamed_Profile --
7129 -----------------------------
7131 procedure Inherit_Renamed_Profile (New_S : Entity_Id; Old_S : Entity_Id) is
7138 if Ekind (Old_S) = E_Operator then
7139 New_F := First_Formal (New_S);
7141 while Present (New_F) loop
7142 Set_Etype (New_F, Base_Type (Etype (New_F)));
7143 Next_Formal (New_F);
7146 Set_Etype (New_S, Base_Type (Etype (New_S)));
7149 New_F := First_Formal (New_S);
7150 Old_F := First_Formal (Old_S);
7152 while Present (New_F) loop
7153 New_T := Etype (New_F);
7154 Old_T := Etype (Old_F);
7156 -- If the new type is a renaming of the old one, as is the
7157 -- case for actuals in instances, retain its name, to simplify
7158 -- later disambiguation.
7160 if Nkind (Parent (New_T)) = N_Subtype_Declaration
7161 and then Is_Entity_Name (Subtype_Indication (Parent (New_T)))
7162 and then Entity (Subtype_Indication (Parent (New_T))) = Old_T
7166 Set_Etype (New_F, Old_T);
7169 Next_Formal (New_F);
7170 Next_Formal (Old_F);
7173 if Ekind_In (Old_S, E_Function, E_Enumeration_Literal) then
7174 Set_Etype (New_S, Etype (Old_S));
7177 end Inherit_Renamed_Profile;
7183 procedure Initialize is
7188 -------------------------
7189 -- Install_Use_Clauses --
7190 -------------------------
7192 procedure Install_Use_Clauses
7194 Force_Installation : Boolean := False)
7202 while Present (U) loop
7204 -- Case of USE package
7206 if Nkind (U) = N_Use_Package_Clause then
7207 P := First (Names (U));
7208 while Present (P) loop
7211 if Ekind (Id) = E_Package then
7213 Note_Redundant_Use (P);
7215 elsif Present (Renamed_Object (Id))
7216 and then In_Use (Renamed_Object (Id))
7218 Note_Redundant_Use (P);
7220 elsif Force_Installation or else Applicable_Use (P) then
7221 Use_One_Package (Id, U);
7232 P := First (Subtype_Marks (U));
7233 while Present (P) loop
7234 if not Is_Entity_Name (P)
7235 or else No (Entity (P))
7239 elsif Entity (P) /= Any_Type then
7247 Next_Use_Clause (U);
7249 end Install_Use_Clauses;
7251 -------------------------------------
7252 -- Is_Appropriate_For_Entry_Prefix --
7253 -------------------------------------
7255 function Is_Appropriate_For_Entry_Prefix (T : Entity_Id) return Boolean is
7256 P_Type : Entity_Id := T;
7259 if Is_Access_Type (P_Type) then
7260 P_Type := Designated_Type (P_Type);
7263 return Is_Task_Type (P_Type) or else Is_Protected_Type (P_Type);
7264 end Is_Appropriate_For_Entry_Prefix;
7266 -------------------------------
7267 -- Is_Appropriate_For_Record --
7268 -------------------------------
7270 function Is_Appropriate_For_Record (T : Entity_Id) return Boolean is
7272 function Has_Components (T1 : Entity_Id) return Boolean;
7273 -- Determine if given type has components (i.e. is either a record
7274 -- type or a type that has discriminants).
7276 --------------------
7277 -- Has_Components --
7278 --------------------
7280 function Has_Components (T1 : Entity_Id) return Boolean is
7282 return Is_Record_Type (T1)
7283 or else (Is_Private_Type (T1) and then Has_Discriminants (T1))
7284 or else (Is_Task_Type (T1) and then Has_Discriminants (T1))
7285 or else (Is_Incomplete_Type (T1)
7286 and then From_Limited_With (T1)
7287 and then Present (Non_Limited_View (T1))
7288 and then Is_Record_Type
7289 (Get_Full_View (Non_Limited_View (T1))));
7292 -- Start of processing for Is_Appropriate_For_Record
7297 and then (Has_Components (T)
7298 or else (Is_Access_Type (T)
7299 and then Has_Components (Designated_Type (T))));
7300 end Is_Appropriate_For_Record;
7302 ------------------------
7303 -- Note_Redundant_Use --
7304 ------------------------
7306 procedure Note_Redundant_Use (Clause : Node_Id) is
7307 Pack_Name : constant Entity_Id := Entity (Clause);
7308 Cur_Use : constant Node_Id := Current_Use_Clause (Pack_Name);
7309 Decl : constant Node_Id := Parent (Clause);
7311 Prev_Use : Node_Id := Empty;
7312 Redundant : Node_Id := Empty;
7313 -- The Use_Clause which is actually redundant. In the simplest case it
7314 -- is Pack itself, but when we compile a body we install its context
7315 -- before that of its spec, in which case it is the use_clause in the
7316 -- spec that will appear to be redundant, and we want the warning to be
7317 -- placed on the body. Similar complications appear when the redundancy
7318 -- is between a child unit and one of its ancestors.
7321 Set_Redundant_Use (Clause, True);
7323 if not Comes_From_Source (Clause)
7325 or else not Warn_On_Redundant_Constructs
7330 if not Is_Compilation_Unit (Current_Scope) then
7332 -- If the use_clause is in an inner scope, it is made redundant by
7333 -- some clause in the current context, with one exception: If we're
7334 -- compiling a nested package body, and the use_clause comes from the
7335 -- corresponding spec, the clause is not necessarily fully redundant,
7336 -- so we should not warn. If a warning was warranted, it would have
7337 -- been given when the spec was processed.
7339 if Nkind (Parent (Decl)) = N_Package_Specification then
7341 Package_Spec_Entity : constant Entity_Id :=
7342 Defining_Unit_Name (Parent (Decl));
7344 if In_Package_Body (Package_Spec_Entity) then
7350 Redundant := Clause;
7351 Prev_Use := Cur_Use;
7353 elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
7355 Cur_Unit : constant Unit_Number_Type := Get_Source_Unit (Cur_Use);
7356 New_Unit : constant Unit_Number_Type := Get_Source_Unit (Clause);
7360 if Cur_Unit = New_Unit then
7362 -- Redundant clause in same body
7364 Redundant := Clause;
7365 Prev_Use := Cur_Use;
7367 elsif Cur_Unit = Current_Sem_Unit then
7369 -- If the new clause is not in the current unit it has been
7370 -- analyzed first, and it makes the other one redundant.
7371 -- However, if the new clause appears in a subunit, Cur_Unit
7372 -- is still the parent, and in that case the redundant one
7373 -- is the one appearing in the subunit.
7375 if Nkind (Unit (Cunit (New_Unit))) = N_Subunit then
7376 Redundant := Clause;
7377 Prev_Use := Cur_Use;
7379 -- Most common case: redundant clause in body,
7380 -- original clause in spec. Current scope is spec entity.
7385 Unit (Library_Unit (Cunit (Current_Sem_Unit))))
7387 Redundant := Cur_Use;
7391 -- The new clause may appear in an unrelated unit, when
7392 -- the parents of a generic are being installed prior to
7393 -- instantiation. In this case there must be no warning.
7394 -- We detect this case by checking whether the current top
7395 -- of the stack is related to the current compilation.
7397 Scop := Current_Scope;
7398 while Present (Scop) and then Scop /= Standard_Standard loop
7399 if Is_Compilation_Unit (Scop)
7400 and then not Is_Child_Unit (Scop)
7404 elsif Scop = Cunit_Entity (Current_Sem_Unit) then
7408 Scop := Scope (Scop);
7411 Redundant := Cur_Use;
7415 elsif New_Unit = Current_Sem_Unit then
7416 Redundant := Clause;
7417 Prev_Use := Cur_Use;
7420 -- Neither is the current unit, so they appear in parent or
7421 -- sibling units. Warning will be emitted elsewhere.
7427 elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Declaration
7428 and then Present (Parent_Spec (Unit (Cunit (Current_Sem_Unit))))
7430 -- Use_clause is in child unit of current unit, and the child unit
7431 -- appears in the context of the body of the parent, so it has been
7432 -- installed first, even though it is the redundant one. Depending on
7433 -- their placement in the context, the visible or the private parts
7434 -- of the two units, either might appear as redundant, but the
7435 -- message has to be on the current unit.
7437 if Get_Source_Unit (Cur_Use) = Current_Sem_Unit then
7438 Redundant := Cur_Use;
7441 Redundant := Clause;
7442 Prev_Use := Cur_Use;
7445 -- If the new use clause appears in the private part of a parent unit
7446 -- it may appear to be redundant w.r.t. a use clause in a child unit,
7447 -- but the previous use clause was needed in the visible part of the
7448 -- child, and no warning should be emitted.
7450 if Nkind (Parent (Decl)) = N_Package_Specification
7452 List_Containing (Decl) = Private_Declarations (Parent (Decl))
7455 Par : constant Entity_Id := Defining_Entity (Parent (Decl));
7456 Spec : constant Node_Id :=
7457 Specification (Unit (Cunit (Current_Sem_Unit)));
7460 if Is_Compilation_Unit (Par)
7461 and then Par /= Cunit_Entity (Current_Sem_Unit)
7462 and then Parent (Cur_Use) = Spec
7464 List_Containing (Cur_Use) = Visible_Declarations (Spec)
7471 -- Finally, if the current use clause is in the context then
7472 -- the clause is redundant when it is nested within the unit.
7474 elsif Nkind (Parent (Cur_Use)) = N_Compilation_Unit
7475 and then Nkind (Parent (Parent (Clause))) /= N_Compilation_Unit
7476 and then Get_Source_Unit (Cur_Use) = Get_Source_Unit (Clause)
7478 Redundant := Clause;
7479 Prev_Use := Cur_Use;
7485 if Present (Redundant) then
7486 Error_Msg_Sloc := Sloc (Prev_Use);
7487 Error_Msg_NE -- CODEFIX
7488 ("& is already use-visible through previous use clause #??",
7489 Redundant, Pack_Name);
7491 end Note_Redundant_Use;
7497 procedure Pop_Scope is
7498 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
7499 S : constant Entity_Id := SST.Entity;
7502 if Debug_Flag_E then
7506 -- Set Default_Storage_Pool field of the library unit if necessary
7508 if Ekind_In (S, E_Package, E_Generic_Package)
7510 Nkind (Parent (Unit_Declaration_Node (S))) = N_Compilation_Unit
7513 Aux : constant Node_Id :=
7514 Aux_Decls_Node (Parent (Unit_Declaration_Node (S)));
7516 if No (Default_Storage_Pool (Aux)) then
7517 Set_Default_Storage_Pool (Aux, Default_Pool);
7522 Scope_Suppress := SST.Save_Scope_Suppress;
7523 Local_Suppress_Stack_Top := SST.Save_Local_Suppress_Stack_Top;
7524 Check_Policy_List := SST.Save_Check_Policy_List;
7525 Default_Pool := SST.Save_Default_Storage_Pool;
7526 SPARK_Mode := SST.Save_SPARK_Mode;
7527 SPARK_Mode_Pragma := SST.Save_SPARK_Mode_Pragma;
7529 if Debug_Flag_W then
7530 Write_Str ("<-- exiting scope: ");
7531 Write_Name (Chars (Current_Scope));
7532 Write_Str (", Depth=");
7533 Write_Int (Int (Scope_Stack.Last));
7537 End_Use_Clauses (SST.First_Use_Clause);
7539 -- If the actions to be wrapped are still there they will get lost
7540 -- causing incomplete code to be generated. It is better to abort in
7541 -- this case (and we do the abort even with assertions off since the
7542 -- penalty is incorrect code generation).
7544 if SST.Actions_To_Be_Wrapped /= Scope_Actions'(others => No_List) then
7545 raise Program_Error;
7548 -- Free last subprogram name if allocated, and pop scope
7550 Free (SST.Last_Subprogram_Name);
7551 Scope_Stack.Decrement_Last;
7558 procedure Push_Scope (S : Entity_Id) is
7559 E : constant Entity_Id := Scope (S);
7562 if Ekind (S) = E_Void then
7565 -- Set scope depth if not a non-concurrent type, and we have not yet set
7566 -- the scope depth. This means that we have the first occurrence of the
7567 -- scope, and this is where the depth is set.
7569 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
7570 and then not Scope_Depth_Set (S)
7572 if S = Standard_Standard then
7573 Set_Scope_Depth_Value (S, Uint_0);
7575 elsif Is_Child_Unit (S) then
7576 Set_Scope_Depth_Value (S, Uint_1);
7578 elsif not Is_Record_Type (Current_Scope) then
7579 if Ekind (S) = E_Loop then
7580 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
7582 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
7587 Scope_Stack.Increment_Last;
7590 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
7594 SST.Save_Scope_Suppress := Scope_Suppress;
7595 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
7596 SST.Save_Check_Policy_List := Check_Policy_List;
7597 SST.Save_Default_Storage_Pool := Default_Pool;
7598 SST.Save_SPARK_Mode := SPARK_Mode;
7599 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
7601 if Scope_Stack.Last > Scope_Stack.First then
7602 SST.Component_Alignment_Default := Scope_Stack.Table
7603 (Scope_Stack.Last - 1).
7604 Component_Alignment_Default;
7607 SST.Last_Subprogram_Name := null;
7608 SST.Is_Transient := False;
7609 SST.Node_To_Be_Wrapped := Empty;
7610 SST.Pending_Freeze_Actions := No_List;
7611 SST.Actions_To_Be_Wrapped := (others => No_List);
7612 SST.First_Use_Clause := Empty;
7613 SST.Is_Active_Stack_Base := False;
7614 SST.Previous_Visibility := False;
7617 if Debug_Flag_W then
7618 Write_Str ("--> new scope: ");
7619 Write_Name (Chars (Current_Scope));
7620 Write_Str (", Id=");
7621 Write_Int (Int (Current_Scope));
7622 Write_Str (", Depth=");
7623 Write_Int (Int (Scope_Stack.Last));
7627 -- Deal with copying flags from the previous scope to this one. This is
7628 -- not necessary if either scope is standard, or if the new scope is a
7631 if S /= Standard_Standard
7632 and then Scope (S) /= Standard_Standard
7633 and then not Is_Child_Unit (S)
7635 if Nkind (E) not in N_Entity then
7639 -- Copy categorization flags from Scope (S) to S, this is not done
7640 -- when Scope (S) is Standard_Standard since propagation is from
7641 -- library unit entity inwards. Copy other relevant attributes as
7642 -- well (Discard_Names in particular).
7644 -- We only propagate inwards for library level entities,
7645 -- inner level subprograms do not inherit the categorization.
7647 if Is_Library_Level_Entity (S) then
7648 Set_Is_Preelaborated (S, Is_Preelaborated (E));
7649 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
7650 Set_Discard_Names (S, Discard_Names (E));
7651 Set_Suppress_Value_Tracking_On_Call
7652 (S, Suppress_Value_Tracking_On_Call (E));
7653 Set_Categorization_From_Scope (E => S, Scop => E);
7657 if Is_Child_Unit (S)
7658 and then Present (E)
7659 and then Ekind_In (E, E_Package, E_Generic_Package)
7661 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
7664 Aux : constant Node_Id :=
7665 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
7667 if Present (Default_Storage_Pool (Aux)) then
7668 Default_Pool := Default_Storage_Pool (Aux);
7674 ---------------------
7675 -- Premature_Usage --
7676 ---------------------
7678 procedure Premature_Usage (N : Node_Id) is
7679 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
7680 E : Entity_Id := Entity (N);
7683 -- Within an instance, the analysis of the actual for a formal object
7684 -- does not see the name of the object itself. This is significant only
7685 -- if the object is an aggregate, where its analysis does not do any
7686 -- name resolution on component associations. (see 4717-008). In such a
7687 -- case, look for the visible homonym on the chain.
7689 if In_Instance and then Present (Homonym (E)) then
7691 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
7697 Set_Etype (N, Etype (E));
7702 if Kind = N_Component_Declaration then
7704 ("component&! cannot be used before end of record declaration", N);
7706 elsif Kind = N_Parameter_Specification then
7708 ("formal parameter&! cannot be used before end of specification",
7711 elsif Kind = N_Discriminant_Specification then
7713 ("discriminant&! cannot be used before end of discriminant part",
7716 elsif Kind = N_Procedure_Specification
7717 or else Kind = N_Function_Specification
7720 ("subprogram&! cannot be used before end of its declaration",
7723 elsif Kind = N_Full_Type_Declaration then
7725 ("type& cannot be used before end of its declaration!", N);
7729 ("object& cannot be used before end of its declaration!", N);
7731 end Premature_Usage;
7733 ------------------------
7734 -- Present_System_Aux --
7735 ------------------------
7737 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
7739 Aux_Name : Unit_Name_Type;
7740 Unum : Unit_Number_Type;
7745 function Find_System (C_Unit : Node_Id) return Entity_Id;
7746 -- Scan context clause of compilation unit to find with_clause
7753 function Find_System (C_Unit : Node_Id) return Entity_Id is
7754 With_Clause : Node_Id;
7757 With_Clause := First (Context_Items (C_Unit));
7758 while Present (With_Clause) loop
7759 if (Nkind (With_Clause) = N_With_Clause
7760 and then Chars (Name (With_Clause)) = Name_System)
7761 and then Comes_From_Source (With_Clause)
7772 -- Start of processing for Present_System_Aux
7775 -- The child unit may have been loaded and analyzed already
7777 if Present (System_Aux_Id) then
7780 -- If no previous pragma for System.Aux, nothing to load
7782 elsif No (System_Extend_Unit) then
7785 -- Use the unit name given in the pragma to retrieve the unit.
7786 -- Verify that System itself appears in the context clause of the
7787 -- current compilation. If System is not present, an error will
7788 -- have been reported already.
7791 With_Sys := Find_System (Cunit (Current_Sem_Unit));
7793 The_Unit := Unit (Cunit (Current_Sem_Unit));
7797 (Nkind (The_Unit) = N_Package_Body
7798 or else (Nkind (The_Unit) = N_Subprogram_Body
7799 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
7801 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
7804 if No (With_Sys) and then Present (N) then
7806 -- If we are compiling a subunit, we need to examine its
7807 -- context as well (Current_Sem_Unit is the parent unit);
7809 The_Unit := Parent (N);
7810 while Nkind (The_Unit) /= N_Compilation_Unit loop
7811 The_Unit := Parent (The_Unit);
7814 if Nkind (Unit (The_Unit)) = N_Subunit then
7815 With_Sys := Find_System (The_Unit);
7819 if No (With_Sys) then
7823 Loc := Sloc (With_Sys);
7824 Get_Name_String (Chars (Expression (System_Extend_Unit)));
7825 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
7826 Name_Buffer (1 .. 7) := "system.";
7827 Name_Buffer (Name_Len + 8) := '%';
7828 Name_Buffer (Name_Len + 9) := 's';
7829 Name_Len := Name_Len + 9;
7830 Aux_Name := Name_Find;
7834 (Load_Name => Aux_Name,
7837 Error_Node => With_Sys);
7839 if Unum /= No_Unit then
7840 Semantics (Cunit (Unum));
7842 Defining_Entity (Specification (Unit (Cunit (Unum))));
7845 Make_With_Clause (Loc,
7847 Make_Expanded_Name (Loc,
7848 Chars => Chars (System_Aux_Id),
7849 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
7850 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
7852 Set_Entity (Name (Withn), System_Aux_Id);
7854 Set_Library_Unit (Withn, Cunit (Unum));
7855 Set_Corresponding_Spec (Withn, System_Aux_Id);
7856 Set_First_Name (Withn, True);
7857 Set_Implicit_With (Withn, True);
7859 Insert_After (With_Sys, Withn);
7860 Mark_Rewrite_Insertion (Withn);
7861 Set_Context_Installed (Withn);
7865 -- Here if unit load failed
7868 Error_Msg_Name_1 := Name_System;
7869 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
7871 ("extension package `%.%` does not exist",
7872 Opt.System_Extend_Unit);
7876 end Present_System_Aux;
7878 -------------------------
7879 -- Restore_Scope_Stack --
7880 -------------------------
7882 procedure Restore_Scope_Stack
7884 Handle_Use : Boolean := True)
7886 SS_Last : constant Int := Scope_Stack.Last;
7890 -- Restore visibility of previous scope stack, if any, using the list
7891 -- we saved (we use Remove, since this list will not be used again).
7894 Elmt := Last_Elmt (List);
7895 exit when Elmt = No_Elmt;
7896 Set_Is_Immediately_Visible (Node (Elmt));
7897 Remove_Last_Elmt (List);
7900 -- Restore use clauses
7902 if SS_Last >= Scope_Stack.First
7903 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
7906 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
7908 end Restore_Scope_Stack;
7910 ----------------------
7911 -- Save_Scope_Stack --
7912 ----------------------
7914 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
7915 -- consuming any memory. That is, Save_Scope_Stack took care of removing
7916 -- from immediate visibility entities and Restore_Scope_Stack took care
7917 -- of restoring their visibility analyzing the context of each entity. The
7918 -- problem of such approach is that it was fragile and caused unexpected
7919 -- visibility problems, and indeed one test was found where there was a
7922 -- Furthermore, the following experiment was carried out:
7924 -- - Save_Scope_Stack was modified to store in an Elist1 all those
7925 -- entities whose attribute Is_Immediately_Visible is modified
7926 -- from True to False.
7928 -- - Restore_Scope_Stack was modified to store in another Elist2
7929 -- all the entities whose attribute Is_Immediately_Visible is
7930 -- modified from False to True.
7932 -- - Extra code was added to verify that all the elements of Elist1
7933 -- are found in Elist2
7935 -- This test shows that there may be more occurrences of this problem which
7936 -- have not yet been detected. As a result, we replaced that approach by
7937 -- the current one in which Save_Scope_Stack returns the list of entities
7938 -- whose visibility is changed, and that list is passed to Restore_Scope_
7939 -- Stack to undo that change. This approach is simpler and safer, although
7940 -- it consumes more memory.
7942 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
7943 Result : constant Elist_Id := New_Elmt_List;
7946 SS_Last : constant Int := Scope_Stack.Last;
7948 procedure Remove_From_Visibility (E : Entity_Id);
7949 -- If E is immediately visible then append it to the result and remove
7950 -- it temporarily from visibility.
7952 ----------------------------
7953 -- Remove_From_Visibility --
7954 ----------------------------
7956 procedure Remove_From_Visibility (E : Entity_Id) is
7958 if Is_Immediately_Visible (E) then
7959 Append_Elmt (E, Result);
7960 Set_Is_Immediately_Visible (E, False);
7962 end Remove_From_Visibility;
7964 -- Start of processing for Save_Scope_Stack
7967 if SS_Last >= Scope_Stack.First
7968 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
7971 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
7974 -- If the call is from within a compilation unit, as when called from
7975 -- Rtsfind, make current entries in scope stack invisible while we
7976 -- analyze the new unit.
7978 for J in reverse 0 .. SS_Last loop
7979 exit when Scope_Stack.Table (J).Entity = Standard_Standard
7980 or else No (Scope_Stack.Table (J).Entity);
7982 S := Scope_Stack.Table (J).Entity;
7984 Remove_From_Visibility (S);
7986 E := First_Entity (S);
7987 while Present (E) loop
7988 Remove_From_Visibility (E);
7996 end Save_Scope_Stack;
8002 procedure Set_Use (L : List_Id) is
8004 Pack_Name : Node_Id;
8011 while Present (Decl) loop
8012 if Nkind (Decl) = N_Use_Package_Clause then
8013 Chain_Use_Clause (Decl);
8015 Pack_Name := First (Names (Decl));
8016 while Present (Pack_Name) loop
8017 Pack := Entity (Pack_Name);
8019 if Ekind (Pack) = E_Package
8020 and then Applicable_Use (Pack_Name)
8022 Use_One_Package (Pack, Decl);
8028 elsif Nkind (Decl) = N_Use_Type_Clause then
8029 Chain_Use_Clause (Decl);
8031 Id := First (Subtype_Marks (Decl));
8032 while Present (Id) loop
8033 if Entity (Id) /= Any_Type then
8046 ---------------------
8047 -- Use_One_Package --
8048 ---------------------
8050 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8053 Current_Instance : Entity_Id := Empty;
8055 Private_With_OK : Boolean := False;
8058 if Ekind (P) /= E_Package then
8063 Set_Current_Use_Clause (P, N);
8065 -- Ada 2005 (AI-50217): Check restriction
8067 if From_Limited_With (P) then
8068 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8071 -- Find enclosing instance, if any
8074 Current_Instance := Current_Scope;
8075 while not Is_Generic_Instance (Current_Instance) loop
8076 Current_Instance := Scope (Current_Instance);
8079 if No (Hidden_By_Use_Clause (N)) then
8080 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8084 -- If unit is a package renaming, indicate that the renamed
8085 -- package is also in use (the flags on both entities must
8086 -- remain consistent, and a subsequent use of either of them
8087 -- should be recognized as redundant).
8089 if Present (Renamed_Object (P)) then
8090 Set_In_Use (Renamed_Object (P));
8091 Set_Current_Use_Clause (Renamed_Object (P), N);
8092 Real_P := Renamed_Object (P);
8097 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8098 -- found in the private part of a package specification
8100 if In_Private_Part (Current_Scope)
8101 and then Has_Private_With (P)
8102 and then Is_Child_Unit (Current_Scope)
8103 and then Is_Child_Unit (P)
8104 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8106 Private_With_OK := True;
8109 -- Loop through entities in one package making them potentially
8112 Id := First_Entity (P);
8114 and then (Id /= First_Private_Entity (P)
8115 or else Private_With_OK) -- Ada 2005 (AI-262)
8117 Prev := Current_Entity (Id);
8118 while Present (Prev) loop
8119 if Is_Immediately_Visible (Prev)
8120 and then (not Is_Overloadable (Prev)
8121 or else not Is_Overloadable (Id)
8122 or else (Type_Conformant (Id, Prev)))
8124 if No (Current_Instance) then
8126 -- Potentially use-visible entity remains hidden
8128 goto Next_Usable_Entity;
8130 -- A use clause within an instance hides outer global entities,
8131 -- which are not used to resolve local entities in the
8132 -- instance. Note that the predefined entities in Standard
8133 -- could not have been hidden in the generic by a use clause,
8134 -- and therefore remain visible. Other compilation units whose
8135 -- entities appear in Standard must be hidden in an instance.
8137 -- To determine whether an entity is external to the instance
8138 -- we compare the scope depth of its scope with that of the
8139 -- current instance. However, a generic actual of a subprogram
8140 -- instance is declared in the wrapper package but will not be
8141 -- hidden by a use-visible entity. similarly, an entity that is
8142 -- declared in an enclosing instance will not be hidden by an
8143 -- an entity declared in a generic actual, which can only have
8144 -- been use-visible in the generic and will not have hidden the
8145 -- entity in the generic parent.
8147 -- If Id is called Standard, the predefined package with the
8148 -- same name is in the homonym chain. It has to be ignored
8149 -- because it has no defined scope (being the only entity in
8150 -- the system with this mandated behavior).
8152 elsif not Is_Hidden (Id)
8153 and then Present (Scope (Prev))
8154 and then not Is_Wrapper_Package (Scope (Prev))
8155 and then Scope_Depth (Scope (Prev)) <
8156 Scope_Depth (Current_Instance)
8157 and then (Scope (Prev) /= Standard_Standard
8158 or else Sloc (Prev) > Standard_Location)
8160 if In_Open_Scopes (Scope (Prev))
8161 and then Is_Generic_Instance (Scope (Prev))
8162 and then Present (Associated_Formal_Package (P))
8167 Set_Is_Potentially_Use_Visible (Id);
8168 Set_Is_Immediately_Visible (Prev, False);
8169 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8173 -- A user-defined operator is not use-visible if the predefined
8174 -- operator for the type is immediately visible, which is the case
8175 -- if the type of the operand is in an open scope. This does not
8176 -- apply to user-defined operators that have operands of different
8177 -- types, because the predefined mixed mode operations (multiply
8178 -- and divide) apply to universal types and do not hide anything.
8180 elsif Ekind (Prev) = E_Operator
8181 and then Operator_Matches_Spec (Prev, Id)
8182 and then In_Open_Scopes
8183 (Scope (Base_Type (Etype (First_Formal (Id)))))
8184 and then (No (Next_Formal (First_Formal (Id)))
8185 or else Etype (First_Formal (Id)) =
8186 Etype (Next_Formal (First_Formal (Id)))
8187 or else Chars (Prev) = Name_Op_Expon)
8189 goto Next_Usable_Entity;
8191 -- In an instance, two homonyms may become use_visible through the
8192 -- actuals of distinct formal packages. In the generic, only the
8193 -- current one would have been visible, so make the other one
8196 elsif Present (Current_Instance)
8197 and then Is_Potentially_Use_Visible (Prev)
8198 and then not Is_Overloadable (Prev)
8199 and then Scope (Id) /= Scope (Prev)
8200 and then Used_As_Generic_Actual (Scope (Prev))
8201 and then Used_As_Generic_Actual (Scope (Id))
8202 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8203 Current_Use_Clause (Scope (Id)))
8205 Set_Is_Potentially_Use_Visible (Prev, False);
8206 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8209 Prev := Homonym (Prev);
8212 -- On exit, we know entity is not hidden, unless it is private
8214 if not Is_Hidden (Id)
8215 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8217 Set_Is_Potentially_Use_Visible (Id);
8219 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8220 Set_Is_Potentially_Use_Visible (Full_View (Id));
8224 <<Next_Usable_Entity>>
8228 -- Child units are also made use-visible by a use clause, but they may
8229 -- appear after all visible declarations in the parent entity list.
8231 while Present (Id) loop
8232 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8233 Set_Is_Potentially_Use_Visible (Id);
8239 if Chars (Real_P) = Name_System
8240 and then Scope (Real_P) = Standard_Standard
8241 and then Present_System_Aux (N)
8243 Use_One_Package (System_Aux_Id, N);
8246 end Use_One_Package;
8252 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8254 Is_Known_Used : Boolean;
8258 function Spec_Reloaded_For_Body return Boolean;
8259 -- Determine whether the compilation unit is a package body and the use
8260 -- type clause is in the spec of the same package. Even though the spec
8261 -- was analyzed first, its context is reloaded when analysing the body.
8263 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8264 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8265 -- class-wide operations of ancestor types are use-visible if the
8266 -- ancestor type is visible.
8268 ----------------------------
8269 -- Spec_Reloaded_For_Body --
8270 ----------------------------
8272 function Spec_Reloaded_For_Body return Boolean is
8274 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8276 Spec : constant Node_Id :=
8277 Parent (List_Containing (Parent (Id)));
8280 -- Check whether type is declared in a package specification,
8281 -- and current unit is the corresponding package body. The
8282 -- use clauses themselves may be within a nested package.
8285 Nkind (Spec) = N_Package_Specification
8287 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8288 Cunit_Entity (Current_Sem_Unit));
8293 end Spec_Reloaded_For_Body;
8295 -------------------------------
8296 -- Use_Class_Wide_Operations --
8297 -------------------------------
8299 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8303 function Is_Class_Wide_Operation_Of
8305 T : Entity_Id) return Boolean;
8306 -- Determine whether a subprogram has a class-wide parameter or
8307 -- result that is T'Class.
8309 ---------------------------------
8310 -- Is_Class_Wide_Operation_Of --
8311 ---------------------------------
8313 function Is_Class_Wide_Operation_Of
8315 T : Entity_Id) return Boolean
8320 Formal := First_Formal (Op);
8321 while Present (Formal) loop
8322 if Etype (Formal) = Class_Wide_Type (T) then
8325 Next_Formal (Formal);
8328 if Etype (Op) = Class_Wide_Type (T) then
8333 end Is_Class_Wide_Operation_Of;
8335 -- Start of processing for Use_Class_Wide_Operations
8338 Scop := Scope (Typ);
8339 if not Is_Hidden (Scop) then
8340 Ent := First_Entity (Scop);
8341 while Present (Ent) loop
8342 if Is_Overloadable (Ent)
8343 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8344 and then not Is_Potentially_Use_Visible (Ent)
8346 Set_Is_Potentially_Use_Visible (Ent);
8347 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8354 if Is_Derived_Type (Typ) then
8355 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8357 end Use_Class_Wide_Operations;
8359 -- Start of processing for Use_One_Type
8362 -- It is the type determined by the subtype mark (8.4(8)) whose
8363 -- operations become potentially use-visible.
8365 T := Base_Type (Entity (Id));
8367 -- Either the type itself is used, the package where it is declared
8368 -- is in use or the entity is declared in the current package, thus
8373 or else In_Use (Scope (T))
8374 or else Scope (T) = Current_Scope;
8376 Set_Redundant_Use (Id,
8377 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8379 if Ekind (T) = E_Incomplete_Type then
8380 Error_Msg_N ("premature usage of incomplete type", Id);
8382 elsif In_Open_Scopes (Scope (T)) then
8385 -- A limited view cannot appear in a use_type clause. However, an access
8386 -- type whose designated type is limited has the flag but is not itself
8387 -- a limited view unless we only have a limited view of its enclosing
8390 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8392 ("incomplete type from limited view "
8393 & "cannot appear in use clause", Id);
8395 -- If the subtype mark designates a subtype in a different package,
8396 -- we have to check that the parent type is visible, otherwise the
8397 -- use type clause is a noop. Not clear how to do that???
8399 elsif not Redundant_Use (Id) then
8402 -- If T is tagged, primitive operators on class-wide operands
8403 -- are also available.
8405 if Is_Tagged_Type (T) then
8406 Set_In_Use (Class_Wide_Type (T));
8409 Set_Current_Use_Clause (T, Parent (Id));
8411 -- Iterate over primitive operations of the type. If an operation is
8412 -- already use_visible, it is the result of a previous use_clause,
8413 -- and already appears on the corresponding entity chain. If the
8414 -- clause is being reinstalled, operations are already use-visible.
8420 Op_List := Collect_Primitive_Operations (T);
8421 Elmt := First_Elmt (Op_List);
8422 while Present (Elmt) loop
8423 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
8424 or else Chars (Node (Elmt)) in Any_Operator_Name)
8425 and then not Is_Hidden (Node (Elmt))
8426 and then not Is_Potentially_Use_Visible (Node (Elmt))
8428 Set_Is_Potentially_Use_Visible (Node (Elmt));
8429 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8431 elsif Ada_Version >= Ada_2012
8432 and then All_Present (Parent (Id))
8433 and then not Is_Hidden (Node (Elmt))
8434 and then not Is_Potentially_Use_Visible (Node (Elmt))
8436 Set_Is_Potentially_Use_Visible (Node (Elmt));
8437 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8444 if Ada_Version >= Ada_2012
8445 and then All_Present (Parent (Id))
8446 and then Is_Tagged_Type (T)
8448 Use_Class_Wide_Operations (T);
8452 -- If warning on redundant constructs, check for unnecessary WITH
8454 if Warn_On_Redundant_Constructs
8455 and then Is_Known_Used
8457 -- with P; with P; use P;
8458 -- package P is package X is package body X is
8459 -- type T ... use P.T;
8461 -- The compilation unit is the body of X. GNAT first compiles the
8462 -- spec of X, then proceeds to the body. At that point P is marked
8463 -- as use visible. The analysis then reinstalls the spec along with
8464 -- its context. The use clause P.T is now recognized as redundant,
8465 -- but in the wrong context. Do not emit a warning in such cases.
8466 -- Do not emit a warning either if we are in an instance, there is
8467 -- no redundancy between an outer use_clause and one that appears
8468 -- within the generic.
8470 and then not Spec_Reloaded_For_Body
8471 and then not In_Instance
8473 -- The type already has a use clause
8477 -- Case where we know the current use clause for the type
8479 if Present (Current_Use_Clause (T)) then
8480 Use_Clause_Known : declare
8481 Clause1 : constant Node_Id := Parent (Id);
8482 Clause2 : constant Node_Id := Current_Use_Clause (T);
8489 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
8490 -- Return the appropriate entity for determining which unit
8491 -- has a deeper scope: the defining entity for U, unless U
8492 -- is a package instance, in which case we retrieve the
8493 -- entity of the instance spec.
8495 --------------------
8496 -- Entity_Of_Unit --
8497 --------------------
8499 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
8501 if Nkind (U) = N_Package_Instantiation
8502 and then Analyzed (U)
8504 return Defining_Entity (Instance_Spec (U));
8506 return Defining_Entity (U);
8510 -- Start of processing for Use_Clause_Known
8513 -- If both current use type clause and the use type clause
8514 -- for the type are at the compilation unit level, one of
8515 -- the units must be an ancestor of the other, and the
8516 -- warning belongs on the descendant.
8518 if Nkind (Parent (Clause1)) = N_Compilation_Unit
8520 Nkind (Parent (Clause2)) = N_Compilation_Unit
8522 -- If the unit is a subprogram body that acts as spec,
8523 -- the context clause is shared with the constructed
8524 -- subprogram spec. Clearly there is no redundancy.
8526 if Clause1 = Clause2 then
8530 Unit1 := Unit (Parent (Clause1));
8531 Unit2 := Unit (Parent (Clause2));
8533 -- If both clauses are on same unit, or one is the body
8534 -- of the other, or one of them is in a subunit, report
8535 -- redundancy on the later one.
8537 if Unit1 = Unit2 then
8538 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
8539 Error_Msg_NE -- CODEFIX
8540 ("& is already use-visible through previous "
8541 & "use_type_clause #??", Clause1, T);
8544 elsif Nkind (Unit1) = N_Subunit then
8545 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
8546 Error_Msg_NE -- CODEFIX
8547 ("& is already use-visible through previous "
8548 & "use_type_clause #??", Clause1, T);
8551 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
8552 and then Nkind (Unit1) /= Nkind (Unit2)
8553 and then Nkind (Unit1) /= N_Subunit
8555 Error_Msg_Sloc := Sloc (Clause1);
8556 Error_Msg_NE -- CODEFIX
8557 ("& is already use-visible through previous "
8558 & "use_type_clause #??", Current_Use_Clause (T), T);
8562 -- There is a redundant use type clause in a child unit.
8563 -- Determine which of the units is more deeply nested.
8564 -- If a unit is a package instance, retrieve the entity
8565 -- and its scope from the instance spec.
8567 Ent1 := Entity_Of_Unit (Unit1);
8568 Ent2 := Entity_Of_Unit (Unit2);
8570 if Scope (Ent2) = Standard_Standard then
8571 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
8574 elsif Scope (Ent1) = Standard_Standard then
8575 Error_Msg_Sloc := Sloc (Id);
8578 -- If both units are child units, we determine which one
8579 -- is the descendant by the scope distance to the
8580 -- ultimate parent unit.
8590 and then Present (S2)
8591 and then S1 /= Standard_Standard
8592 and then S2 /= Standard_Standard
8598 if S1 = Standard_Standard then
8599 Error_Msg_Sloc := Sloc (Id);
8602 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
8608 Error_Msg_NE -- CODEFIX
8609 ("& is already use-visible through previous "
8610 & "use_type_clause #??", Err_No, Id);
8612 -- Case where current use type clause and the use type
8613 -- clause for the type are not both at the compilation unit
8614 -- level. In this case we don't have location information.
8617 Error_Msg_NE -- CODEFIX
8618 ("& is already use-visible through previous "
8619 & "use type clause??", Id, T);
8621 end Use_Clause_Known;
8623 -- Here if Current_Use_Clause is not set for T, another case
8624 -- where we do not have the location information available.
8627 Error_Msg_NE -- CODEFIX
8628 ("& is already use-visible through previous "
8629 & "use type clause??", Id, T);
8632 -- The package where T is declared is already used
8634 elsif In_Use (Scope (T)) then
8635 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
8636 Error_Msg_NE -- CODEFIX
8637 ("& is already use-visible through package use clause #??",
8640 -- The current scope is the package where T is declared
8643 Error_Msg_Node_2 := Scope (T);
8644 Error_Msg_NE -- CODEFIX
8645 ("& is already use-visible inside package &??", Id, T);
8654 procedure Write_Info is
8655 Id : Entity_Id := First_Entity (Current_Scope);
8658 -- No point in dumping standard entities
8660 if Current_Scope = Standard_Standard then
8664 Write_Str ("========================================================");
8666 Write_Str (" Defined Entities in ");
8667 Write_Name (Chars (Current_Scope));
8669 Write_Str ("========================================================");
8673 Write_Str ("-- none --");
8677 while Present (Id) loop
8678 Write_Entity_Info (Id, " ");
8683 if Scope (Current_Scope) = Standard_Standard then
8685 -- Print information on the current unit itself
8687 Write_Entity_Info (Current_Scope, " ");
8700 for J in reverse 1 .. Scope_Stack.Last loop
8701 S := Scope_Stack.Table (J).Entity;
8702 Write_Int (Int (S));
8703 Write_Str (" === ");
8704 Write_Name (Chars (S));
8713 procedure we (S : Entity_Id) is
8716 E := First_Entity (S);
8717 while Present (E) loop
8718 Write_Int (Int (E));
8719 Write_Str (" === ");
8720 Write_Name (Chars (E));