1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Disp
; use Exp_Disp
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Fname
; use Fname
;
35 with Freeze
; use Freeze
;
36 with Ghost
; use Ghost
;
37 with Impunit
; use Impunit
;
39 with Lib
.Load
; use Lib
.Load
;
40 with Lib
.Xref
; use Lib
.Xref
;
41 with Namet
; use Namet
;
42 with Namet
.Sp
; use Namet
.Sp
;
43 with Nlists
; use Nlists
;
44 with Nmake
; use Nmake
;
46 with Output
; use Output
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
51 with Sem_Aux
; use Sem_Aux
;
52 with Sem_Cat
; use Sem_Cat
;
53 with Sem_Ch3
; use Sem_Ch3
;
54 with Sem_Ch4
; use Sem_Ch4
;
55 with Sem_Ch6
; use Sem_Ch6
;
56 with Sem_Ch12
; use Sem_Ch12
;
57 with Sem_Ch13
; use Sem_Ch13
;
58 with Sem_Dim
; use Sem_Dim
;
59 with Sem_Disp
; use Sem_Disp
;
60 with Sem_Dist
; use Sem_Dist
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Res
; use Sem_Res
;
63 with Sem_Util
; use Sem_Util
;
64 with Sem_Type
; use Sem_Type
;
65 with Stand
; use Stand
;
66 with Sinfo
; use Sinfo
;
67 with Sinfo
.CN
; use Sinfo
.CN
;
68 with Snames
; use Snames
;
69 with Style
; use Style
;
71 with Targparm
; use Targparm
;
72 with Tbuild
; use Tbuild
;
73 with Uintp
; use Uintp
;
75 package body Sem_Ch8
is
77 ------------------------------------
78 -- Visibility and Name Resolution --
79 ------------------------------------
81 -- This package handles name resolution and the collection of possible
82 -- interpretations for overloaded names, prior to overload resolution.
84 -- Name resolution is the process that establishes a mapping between source
85 -- identifiers and the entities they denote at each point in the program.
86 -- Each entity is represented by a defining occurrence. Each identifier
87 -- that denotes an entity points to the corresponding defining occurrence.
88 -- This is the entity of the applied occurrence. Each occurrence holds
89 -- an index into the names table, where source identifiers are stored.
91 -- Each entry in the names table for an identifier or designator uses the
92 -- Info pointer to hold a link to the currently visible entity that has
93 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
94 -- in package Sem_Util). The visibility is initialized at the beginning of
95 -- semantic processing to make entities in package Standard immediately
96 -- visible. The visibility table is used in a more subtle way when
97 -- compiling subunits (see below).
99 -- Entities that have the same name (i.e. homonyms) are chained. In the
100 -- case of overloaded entities, this chain holds all the possible meanings
101 -- of a given identifier. The process of overload resolution uses type
102 -- information to select from this chain the unique meaning of a given
105 -- Entities are also chained in their scope, through the Next_Entity link.
106 -- As a consequence, the name space is organized as a sparse matrix, where
107 -- each row corresponds to a scope, and each column to a source identifier.
108 -- Open scopes, that is to say scopes currently being compiled, have their
109 -- corresponding rows of entities in order, innermost scope first.
111 -- The scopes of packages that are mentioned in context clauses appear in
112 -- no particular order, interspersed among open scopes. This is because
113 -- in the course of analyzing the context of a compilation, a package
114 -- declaration is first an open scope, and subsequently an element of the
115 -- context. If subunits or child units are present, a parent unit may
116 -- appear under various guises at various times in the compilation.
118 -- When the compilation of the innermost scope is complete, the entities
119 -- defined therein are no longer visible. If the scope is not a package
120 -- declaration, these entities are never visible subsequently, and can be
121 -- removed from visibility chains. If the scope is a package declaration,
122 -- its visible declarations may still be accessible. Therefore the entities
123 -- defined in such a scope are left on the visibility chains, and only
124 -- their visibility (immediately visibility or potential use-visibility)
127 -- The ordering of homonyms on their chain does not necessarily follow
128 -- the order of their corresponding scopes on the scope stack. For
129 -- example, if package P and the enclosing scope both contain entities
130 -- named E, then when compiling the package body the chain for E will
131 -- hold the global entity first, and the local one (corresponding to
132 -- the current inner scope) next. As a result, name resolution routines
133 -- do not assume any relative ordering of the homonym chains, either
134 -- for scope nesting or to order of appearance of context clauses.
136 -- When compiling a child unit, entities in the parent scope are always
137 -- immediately visible. When compiling the body of a child unit, private
138 -- entities in the parent must also be made immediately visible. There
139 -- are separate routines to make the visible and private declarations
140 -- visible at various times (see package Sem_Ch7).
142 -- +--------+ +-----+
143 -- | In use |-------->| EU1 |-------------------------->
144 -- +--------+ +-----+
146 -- +--------+ +-----+ +-----+
147 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
148 -- +--------+ +-----+ +-----+
150 -- +---------+ | +-----+
151 -- | with'ed |------------------------------>| EW2 |--->
152 -- +---------+ | +-----+
154 -- +--------+ +-----+ +-----+
155 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
156 -- +--------+ +-----+ +-----+
158 -- +--------+ +-----+ +-----+
159 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
160 -- +--------+ +-----+ +-----+
164 -- | | with'ed |----------------------------------------->
168 -- (innermost first) | |
169 -- +----------------------------+
170 -- Names table => | Id1 | | | | Id2 |
171 -- +----------------------------+
173 -- Name resolution must deal with several syntactic forms: simple names,
174 -- qualified names, indexed names, and various forms of calls.
176 -- Each identifier points to an entry in the names table. The resolution
177 -- of a simple name consists in traversing the homonym chain, starting
178 -- from the names table. If an entry is immediately visible, it is the one
179 -- designated by the identifier. If only potentially use-visible entities
180 -- are on the chain, we must verify that they do not hide each other. If
181 -- the entity we find is overloadable, we collect all other overloadable
182 -- entities on the chain as long as they are not hidden.
184 -- To resolve expanded names, we must find the entity at the intersection
185 -- of the entity chain for the scope (the prefix) and the homonym chain
186 -- for the selector. In general, homonym chains will be much shorter than
187 -- entity chains, so it is preferable to start from the names table as
188 -- well. If the entity found is overloadable, we must collect all other
189 -- interpretations that are defined in the scope denoted by the prefix.
191 -- For records, protected types, and tasks, their local entities are
192 -- removed from visibility chains on exit from the corresponding scope.
193 -- From the outside, these entities are always accessed by selected
194 -- notation, and the entity chain for the record type, protected type,
195 -- etc. is traversed sequentially in order to find the designated entity.
197 -- The discriminants of a type and the operations of a protected type or
198 -- task are unchained on exit from the first view of the type, (such as
199 -- a private or incomplete type declaration, or a protected type speci-
200 -- fication) and re-chained when compiling the second view.
202 -- In the case of operators, we do not make operators on derived types
203 -- explicit. As a result, the notation P."+" may denote either a user-
204 -- defined function with name "+", or else an implicit declaration of the
205 -- operator "+" in package P. The resolution of expanded names always
206 -- tries to resolve an operator name as such an implicitly defined entity,
207 -- in addition to looking for explicit declarations.
209 -- All forms of names that denote entities (simple names, expanded names,
210 -- character literals in some cases) have a Entity attribute, which
211 -- identifies the entity denoted by the name.
213 ---------------------
214 -- The Scope Stack --
215 ---------------------
217 -- The Scope stack keeps track of the scopes currently been compiled.
218 -- Every entity that contains declarations (including records) is placed
219 -- on the scope stack while it is being processed, and removed at the end.
220 -- Whenever a non-package scope is exited, the entities defined therein
221 -- are removed from the visibility table, so that entities in outer scopes
222 -- become visible (see previous description). On entry to Sem, the scope
223 -- stack only contains the package Standard. As usual, subunits complicate
224 -- this picture ever so slightly.
226 -- The Rtsfind mechanism can force a call to Semantics while another
227 -- compilation is in progress. The unit retrieved by Rtsfind must be
228 -- compiled in its own context, and has no access to the visibility of
229 -- the unit currently being compiled. The procedures Save_Scope_Stack and
230 -- Restore_Scope_Stack make entities in current open scopes invisible
231 -- before compiling the retrieved unit, and restore the compilation
232 -- environment afterwards.
234 ------------------------
235 -- Compiling subunits --
236 ------------------------
238 -- Subunits must be compiled in the environment of the corresponding stub,
239 -- that is to say with the same visibility into the parent (and its
240 -- context) that is available at the point of the stub declaration, but
241 -- with the additional visibility provided by the context clause of the
242 -- subunit itself. As a result, compilation of a subunit forces compilation
243 -- of the parent (see description in lib-). At the point of the stub
244 -- declaration, Analyze is called recursively to compile the proper body of
245 -- the subunit, but without reinitializing the names table, nor the scope
246 -- stack (i.e. standard is not pushed on the stack). In this fashion the
247 -- context of the subunit is added to the context of the parent, and the
248 -- subunit is compiled in the correct environment. Note that in the course
249 -- of processing the context of a subunit, Standard will appear twice on
250 -- the scope stack: once for the parent of the subunit, and once for the
251 -- unit in the context clause being compiled. However, the two sets of
252 -- entities are not linked by homonym chains, so that the compilation of
253 -- any context unit happens in a fresh visibility environment.
255 -------------------------------
256 -- Processing of USE Clauses --
257 -------------------------------
259 -- Every defining occurrence has a flag indicating if it is potentially use
260 -- visible. Resolution of simple names examines this flag. The processing
261 -- of use clauses consists in setting this flag on all visible entities
262 -- defined in the corresponding package. On exit from the scope of the use
263 -- clause, the corresponding flag must be reset. However, a package may
264 -- appear in several nested use clauses (pathological but legal, alas)
265 -- which forces us to use a slightly more involved scheme:
267 -- a) The defining occurrence for a package holds a flag -In_Use- to
268 -- indicate that it is currently in the scope of a use clause. If a
269 -- redundant use clause is encountered, then the corresponding occurrence
270 -- of the package name is flagged -Redundant_Use-.
272 -- b) On exit from a scope, the use clauses in its declarative part are
273 -- scanned. The visibility flag is reset in all entities declared in
274 -- package named in a use clause, as long as the package is not flagged
275 -- as being in a redundant use clause (in which case the outer use
276 -- clause is still in effect, and the direct visibility of its entities
277 -- must be retained).
279 -- Note that entities are not removed from their homonym chains on exit
280 -- from the package specification. A subsequent use clause does not need
281 -- to rechain the visible entities, but only to establish their direct
284 -----------------------------------
285 -- Handling private declarations --
286 -----------------------------------
288 -- The principle that each entity has a single defining occurrence clashes
289 -- with the presence of two separate definitions for private types: the
290 -- first is the private type declaration, and second is the full type
291 -- declaration. It is important that all references to the type point to
292 -- the same defining occurrence, namely the first one. To enforce the two
293 -- separate views of the entity, the corresponding information is swapped
294 -- between the two declarations. Outside of the package, the defining
295 -- occurrence only contains the private declaration information, while in
296 -- the private part and the body of the package the defining occurrence
297 -- contains the full declaration. To simplify the swap, the defining
298 -- occurrence that currently holds the private declaration points to the
299 -- full declaration. During semantic processing the defining occurrence
300 -- also points to a list of private dependents, that is to say access types
301 -- or composite types whose designated types or component types are
302 -- subtypes or derived types of the private type in question. After the
303 -- full declaration has been seen, the private dependents are updated to
304 -- indicate that they have full definitions.
306 ------------------------------------
307 -- Handling of Undefined Messages --
308 ------------------------------------
310 -- In normal mode, only the first use of an undefined identifier generates
311 -- a message. The table Urefs is used to record error messages that have
312 -- been issued so that second and subsequent ones do not generate further
313 -- messages. However, the second reference causes text to be added to the
314 -- original undefined message noting "(more references follow)". The
315 -- full error list option (-gnatf) forces messages to be generated for
316 -- every reference and disconnects the use of this table.
318 type Uref_Entry
is record
320 -- Node for identifier for which original message was posted. The
321 -- Chars field of this identifier is used to detect later references
322 -- to the same identifier.
325 -- Records error message Id of original undefined message. Reset to
326 -- No_Error_Msg after the second occurrence, where it is used to add
327 -- text to the original message as described above.
330 -- Set if the message is not visible rather than undefined
333 -- Records location of error message. Used to make sure that we do
334 -- not consider a, b : undefined as two separate instances, which
335 -- would otherwise happen, since the parser converts this sequence
336 -- to a : undefined; b : undefined.
340 package Urefs
is new Table
.Table
(
341 Table_Component_Type
=> Uref_Entry
,
342 Table_Index_Type
=> Nat
,
343 Table_Low_Bound
=> 1,
345 Table_Increment
=> 100,
346 Table_Name
=> "Urefs");
348 Candidate_Renaming
: Entity_Id
;
349 -- Holds a candidate interpretation that appears in a subprogram renaming
350 -- declaration and does not match the given specification, but matches at
351 -- least on the first formal. Allows better error message when given
352 -- specification omits defaulted parameters, a common error.
354 -----------------------
355 -- Local Subprograms --
356 -----------------------
358 procedure Analyze_Generic_Renaming
361 -- Common processing for all three kinds of generic renaming declarations.
362 -- Enter new name and indicate that it renames the generic unit.
364 procedure Analyze_Renamed_Character
368 -- Renamed entity is given by a character literal, which must belong
369 -- to the return type of the new entity. Is_Body indicates whether the
370 -- declaration is a renaming_as_body. If the original declaration has
371 -- already been frozen (because of an intervening body, e.g.) the body of
372 -- the function must be built now. The same applies to the following
373 -- various renaming procedures.
375 procedure Analyze_Renamed_Dereference
379 -- Renamed entity is given by an explicit dereference. Prefix must be a
380 -- conformant access_to_subprogram type.
382 procedure Analyze_Renamed_Entry
386 -- If the renamed entity in a subprogram renaming is an entry or protected
387 -- subprogram, build a body for the new entity whose only statement is a
388 -- call to the renamed entity.
390 procedure Analyze_Renamed_Family_Member
394 -- Used when the renamed entity is an indexed component. The prefix must
395 -- denote an entry family.
397 procedure Analyze_Renamed_Primitive_Operation
401 -- If the renamed entity in a subprogram renaming is a primitive operation
402 -- or a class-wide operation in prefix form, save the target object,
403 -- which must be added to the list of actuals in any subsequent call.
404 -- The renaming operation is intrinsic because the compiler must in
405 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
407 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
408 -- Common code to Use_One_Package and Set_Use, to determine whether use
409 -- clause must be processed. Pack_Name is an entity name that references
410 -- the package in question.
412 procedure Attribute_Renaming
(N
: Node_Id
);
413 -- Analyze renaming of attribute as subprogram. The renaming declaration N
414 -- is rewritten as a subprogram body that returns the attribute reference
415 -- applied to the formals of the function.
417 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
418 -- Set Entity, with style check if need be. For a discriminant reference,
419 -- replace by the corresponding discriminal, i.e. the parameter of the
420 -- initialization procedure that corresponds to the discriminant.
422 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
423 -- A renaming_as_body may occur after the entity of the original decla-
424 -- ration has been frozen. In that case, the body of the new entity must
425 -- be built now, because the usual mechanism of building the renamed
426 -- body at the point of freezing will not work. Subp is the subprogram
427 -- for which N provides the Renaming_As_Body.
429 procedure Check_In_Previous_With_Clause
432 -- N is a use_package clause and Nam the package name, or N is a use_type
433 -- clause and Nam is the prefix of the type name. In either case, verify
434 -- that the package is visible at that point in the context: either it
435 -- appears in a previous with_clause, or because it is a fully qualified
436 -- name and the root ancestor appears in a previous with_clause.
438 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
439 -- Verify that the entity in a renaming declaration that is a library unit
440 -- is itself a library unit and not a nested unit or subunit. Also check
441 -- that if the renaming is a child unit of a generic parent, then the
442 -- renamed unit must also be a child unit of that parent. Finally, verify
443 -- that a renamed generic unit is not an implicit child declared within
444 -- an instance of the parent.
446 procedure Chain_Use_Clause
(N
: Node_Id
);
447 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
448 -- the proper scope table entry. This is usually the current scope, but it
449 -- will be an inner scope when installing the use clauses of the private
450 -- declarations of a parent unit prior to compiling the private part of a
451 -- child unit. This chain is traversed when installing/removing use clauses
452 -- when compiling a subunit or instantiating a generic body on the fly,
453 -- when it is necessary to save and restore full environments.
455 function Enclosing_Instance
return Entity_Id
;
456 -- In an instance nested within another one, several semantic checks are
457 -- unnecessary because the legality of the nested instance has been checked
458 -- in the enclosing generic unit. This applies in particular to legality
459 -- checks on actuals for formal subprograms of the inner instance, which
460 -- are checked as subprogram renamings, and may be complicated by confusion
461 -- in private/full views. This function returns the instance enclosing the
462 -- current one if there is such, else it returns Empty.
464 -- If the renaming determines the entity for the default of a formal
465 -- subprogram nested within another instance, choose the innermost
466 -- candidate. This is because if the formal has a box, and we are within
467 -- an enclosing instance where some candidate interpretations are local
468 -- to this enclosing instance, we know that the default was properly
469 -- resolved when analyzing the generic, so we prefer the local
470 -- candidates to those that are external. This is not always the case
471 -- but is a reasonable heuristic on the use of nested generics. The
472 -- proper solution requires a full renaming model.
474 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
475 -- Find a type derived from Character or Wide_Character in the prefix of N.
476 -- Used to resolved qualified names whose selector is a character literal.
478 function Has_Private_With
(E
: Entity_Id
) return Boolean;
479 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
480 -- private with on E.
482 procedure Find_Expanded_Name
(N
: Node_Id
);
483 -- The input is a selected component known to be an expanded name. Verify
484 -- legality of selector given the scope denoted by prefix, and change node
485 -- N into a expanded name with a properly set Entity field.
487 function Find_Renamed_Entity
491 Is_Actual
: Boolean := False) return Entity_Id
;
492 -- Find the renamed entity that corresponds to the given parameter profile
493 -- in a subprogram renaming declaration. The renamed entity may be an
494 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
495 -- indicates that the renaming is the one generated for an actual subpro-
496 -- gram in an instance, for which special visibility checks apply.
498 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
499 -- N is an expanded name whose selector is an operator name (e.g. P."+").
500 -- declarative part contains an implicit declaration of an operator if it
501 -- has a declaration of a type to which one of the predefined operators
502 -- apply. The existence of this routine is an implementation artifact. A
503 -- more straightforward but more space-consuming choice would be to make
504 -- all inherited operators explicit in the symbol table.
506 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
507 -- A subprogram defined by a renaming declaration inherits the parameter
508 -- profile of the renamed entity. The subtypes given in the subprogram
509 -- specification are discarded and replaced with those of the renamed
510 -- subprogram, which are then used to recheck the default values.
512 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
513 -- Prefix is appropriate for record if it is of a record type, or an access
516 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
517 -- True if it is of a task type, a protected type, or else an access to one
520 procedure Note_Redundant_Use
(Clause
: Node_Id
);
521 -- Mark the name in a use clause as redundant if the corresponding entity
522 -- is already use-visible. Emit a warning if the use clause comes from
523 -- source and the proper warnings are enabled.
525 procedure Premature_Usage
(N
: Node_Id
);
526 -- Diagnose usage of an entity before it is visible
528 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
529 -- Make visible entities declared in package P potentially use-visible
530 -- in the current context. Also used in the analysis of subunits, when
531 -- re-installing use clauses of parent units. N is the use_clause that
532 -- names P (and possibly other packages).
534 procedure Use_One_Type
(Id
: Node_Id
; Installed
: Boolean := False);
535 -- Id is the subtype mark from a use type clause. This procedure makes
536 -- the primitive operators of the type potentially use-visible. The
537 -- boolean flag Installed indicates that the clause is being reinstalled
538 -- after previous analysis, and primitive operations are already chained
539 -- on the Used_Operations list of the clause.
541 procedure Write_Info
;
542 -- Write debugging information on entities declared in current scope
544 --------------------------------
545 -- Analyze_Exception_Renaming --
546 --------------------------------
548 -- The language only allows a single identifier, but the tree holds an
549 -- identifier list. The parser has already issued an error message if
550 -- there is more than one element in the list.
552 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
553 GM
: constant Ghost_Mode_Type
:= Ghost_Mode
;
554 Id
: constant Entity_Id
:= Defining_Entity
(N
);
555 Nam
: constant Node_Id
:= Name
(N
);
558 -- The exception renaming declaration may be subject to pragma Ghost
559 -- with policy Ignore. Set the mode now to ensure that any nodes
560 -- generated during analysis and expansion are properly flagged as
564 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
569 Set_Ekind
(Id
, E_Exception
);
570 Set_Etype
(Id
, Standard_Exception_Type
);
571 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
573 if Is_Entity_Name
(Nam
)
574 and then Present
(Entity
(Nam
))
575 and then Ekind
(Entity
(Nam
)) = E_Exception
577 if Present
(Renamed_Object
(Entity
(Nam
))) then
578 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
580 Set_Renamed_Object
(Id
, Entity
(Nam
));
583 -- The exception renaming declaration may become Ghost if it renames
586 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
588 Error_Msg_N
("invalid exception name in renaming", Nam
);
591 -- Implementation-defined aspect specifications can appear in a renaming
592 -- declaration, but not language-defined ones. The call to procedure
593 -- Analyze_Aspect_Specifications will take care of this error check.
595 if Has_Aspects
(N
) then
596 Analyze_Aspect_Specifications
(N
, Id
);
599 -- Restore the original Ghost mode once analysis and expansion have
603 end Analyze_Exception_Renaming
;
605 ---------------------------
606 -- Analyze_Expanded_Name --
607 ---------------------------
609 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
611 -- If the entity pointer is already set, this is an internal node, or a
612 -- node that is analyzed more than once, after a tree modification. In
613 -- such a case there is no resolution to perform, just set the type. For
614 -- completeness, analyze prefix as well.
616 if Present
(Entity
(N
)) then
617 if Is_Type
(Entity
(N
)) then
618 Set_Etype
(N
, Entity
(N
));
620 Set_Etype
(N
, Etype
(Entity
(N
)));
623 Analyze
(Prefix
(N
));
626 Find_Expanded_Name
(N
);
629 Analyze_Dimension
(N
);
630 end Analyze_Expanded_Name
;
632 ---------------------------------------
633 -- Analyze_Generic_Function_Renaming --
634 ---------------------------------------
636 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
638 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
639 end Analyze_Generic_Function_Renaming
;
641 --------------------------------------
642 -- Analyze_Generic_Package_Renaming --
643 --------------------------------------
645 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
647 -- Test for the Text_IO special unit case here, since we may be renaming
648 -- one of the subpackages of Text_IO, then join common routine.
650 Check_Text_IO_Special_Unit
(Name
(N
));
652 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
653 end Analyze_Generic_Package_Renaming
;
655 ----------------------------------------
656 -- Analyze_Generic_Procedure_Renaming --
657 ----------------------------------------
659 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
661 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
662 end Analyze_Generic_Procedure_Renaming
;
664 ------------------------------
665 -- Analyze_Generic_Renaming --
666 ------------------------------
668 procedure Analyze_Generic_Renaming
672 GM
: constant Ghost_Mode_Type
:= Ghost_Mode
;
673 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
676 Inst
: Boolean := False;
677 -- Prevent junk warning
680 if Name
(N
) = Error
then
684 -- The generic renaming declaration may be subject to pragma Ghost with
685 -- policy Ignore. Set the mode now to ensure that any nodes generated
686 -- during analysis and expansion are properly flagged as ignored Ghost.
689 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
691 Generate_Definition
(New_P
);
693 if Current_Scope
/= Standard_Standard
then
694 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
697 if Nkind
(Name
(N
)) = N_Selected_Component
then
698 Check_Generic_Child_Unit
(Name
(N
), Inst
);
703 if not Is_Entity_Name
(Name
(N
)) then
704 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
707 Old_P
:= Entity
(Name
(N
));
711 Set_Ekind
(New_P
, K
);
713 if Etype
(Old_P
) = Any_Type
then
716 elsif Ekind
(Old_P
) /= K
then
717 Error_Msg_N
("invalid generic unit name", Name
(N
));
720 if Present
(Renamed_Object
(Old_P
)) then
721 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
723 Set_Renamed_Object
(New_P
, Old_P
);
726 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
727 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
729 Set_Etype
(New_P
, Etype
(Old_P
));
730 Set_Has_Completion
(New_P
);
732 -- The generic renaming declaration may become Ghost if it renames a
735 Mark_Renaming_As_Ghost
(N
, Old_P
);
737 if In_Open_Scopes
(Old_P
) then
738 Error_Msg_N
("within its scope, generic denotes its instance", N
);
741 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
742 -- renamings and subsequent instantiations of Unchecked_Conversion.
744 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
745 Set_Is_Intrinsic_Subprogram
746 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
749 Check_Library_Unit_Renaming
(N
, Old_P
);
752 -- Implementation-defined aspect specifications can appear in a renaming
753 -- declaration, but not language-defined ones. The call to procedure
754 -- Analyze_Aspect_Specifications will take care of this error check.
756 if Has_Aspects
(N
) then
757 Analyze_Aspect_Specifications
(N
, New_P
);
760 -- Restore the original Ghost mode once analysis and expansion have
764 end Analyze_Generic_Renaming
;
766 -----------------------------
767 -- Analyze_Object_Renaming --
768 -----------------------------
770 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
771 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
772 Loc
: constant Source_Ptr
:= Sloc
(N
);
773 Nam
: constant Node_Id
:= Name
(N
);
778 procedure Check_Constrained_Object
;
779 -- If the nominal type is unconstrained but the renamed object is
780 -- constrained, as can happen with renaming an explicit dereference or
781 -- a function return, build a constrained subtype from the object. If
782 -- the renaming is for a formal in an accept statement, the analysis
783 -- has already established its actual subtype. This is only relevant
784 -- if the renamed object is an explicit dereference.
786 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
787 -- Determine whether entity E is inside a generic cope
789 ------------------------------
790 -- Check_Constrained_Object --
791 ------------------------------
793 procedure Check_Constrained_Object
is
794 Typ
: constant Entity_Id
:= Etype
(Nam
);
798 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
799 and then Is_Composite_Type
(Etype
(Nam
))
800 and then not Is_Constrained
(Etype
(Nam
))
801 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
802 and then Expander_Active
804 -- If Actual_Subtype is already set, nothing to do
806 if Ekind_In
(Id
, E_Variable
, E_Constant
)
807 and then Present
(Actual_Subtype
(Id
))
811 -- A renaming of an unchecked union has no actual subtype
813 elsif Is_Unchecked_Union
(Typ
) then
816 -- If a record is limited its size is invariant. This is the case
817 -- in particular with record types with an access discirminant
818 -- that are used in iterators. This is an optimization, but it
819 -- also prevents typing anomalies when the prefix is further
820 -- expanded. Limited types with discriminants are included.
822 elsif Is_Limited_Record
(Typ
)
824 (Ekind
(Typ
) = E_Limited_Private_Type
825 and then Has_Discriminants
(Typ
)
826 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
831 Subt
:= Make_Temporary
(Loc
, 'T');
832 Remove_Side_Effects
(Nam
);
834 Make_Subtype_Declaration
(Loc
,
835 Defining_Identifier
=> Subt
,
836 Subtype_Indication
=>
837 Make_Subtype_From_Expr
(Nam
, Typ
)));
838 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
839 Set_Etype
(Nam
, Subt
);
841 -- Freeze subtype at once, to prevent order of elaboration
842 -- issues in the backend. The renamed object exists, so its
843 -- type is already frozen in any case.
845 Freeze_Before
(N
, Subt
);
848 end Check_Constrained_Object
;
850 ----------------------
851 -- In_Generic_Scope --
852 ----------------------
854 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
859 while Present
(S
) and then S
/= Standard_Standard
loop
860 if Is_Generic_Unit
(S
) then
868 end In_Generic_Scope
;
872 GM
: constant Ghost_Mode_Type
:= Ghost_Mode
;
874 -- Start of processing for Analyze_Object_Renaming
881 -- The object renaming declaration may be subject to pragma Ghost with
882 -- policy Ignore. Set the mode now to ensure that any nodes generated
883 -- during analysis and expansion are properly flagged as ignored Ghost.
886 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
888 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
891 -- The renaming of a component that depends on a discriminant requires
892 -- an actual subtype, because in subsequent use of the object Gigi will
893 -- be unable to locate the actual bounds. This explicit step is required
894 -- when the renaming is generated in removing side effects of an
895 -- already-analyzed expression.
897 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
899 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
901 if Present
(Dec
) then
902 Insert_Action
(N
, Dec
);
903 T
:= Defining_Identifier
(Dec
);
907 -- Complete analysis of the subtype mark in any case, for ASIS use
909 if Present
(Subtype_Mark
(N
)) then
910 Find_Type
(Subtype_Mark
(N
));
913 elsif Present
(Subtype_Mark
(N
)) then
914 Find_Type
(Subtype_Mark
(N
));
915 T
:= Entity
(Subtype_Mark
(N
));
918 -- Reject renamings of conversions unless the type is tagged, or
919 -- the conversion is implicit (which can occur for cases of anonymous
920 -- access types in Ada 2012).
922 if Nkind
(Nam
) = N_Type_Conversion
923 and then Comes_From_Source
(Nam
)
924 and then not Is_Tagged_Type
(T
)
927 ("renaming of conversion only allowed for tagged types", Nam
);
932 -- If the renamed object is a function call of a limited type,
933 -- the expansion of the renaming is complicated by the presence
934 -- of various temporaries and subtypes that capture constraints
935 -- of the renamed object. Rewrite node as an object declaration,
936 -- whose expansion is simpler. Given that the object is limited
937 -- there is no copy involved and no performance hit.
939 if Nkind
(Nam
) = N_Function_Call
940 and then Is_Limited_View
(Etype
(Nam
))
941 and then not Is_Constrained
(Etype
(Nam
))
942 and then Comes_From_Source
(N
)
945 Set_Ekind
(Id
, E_Constant
);
947 Make_Object_Declaration
(Loc
,
948 Defining_Identifier
=> Id
,
949 Constant_Present
=> True,
950 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
951 Expression
=> Relocate_Node
(Nam
)));
955 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
956 -- when renaming declaration has a named access type. The Ada 2012
957 -- coverage rules allow an anonymous access type in the context of
958 -- an expected named general access type, but the renaming rules
959 -- require the types to be the same. (An exception is when the type
960 -- of the renaming is also an anonymous access type, which can only
961 -- happen due to a renaming created by the expander.)
963 if Nkind
(Nam
) = N_Type_Conversion
964 and then not Comes_From_Source
(Nam
)
965 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
966 and then Ekind
(T
) /= E_Anonymous_Access_Type
968 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
971 -- Check that a class-wide object is not being renamed as an object
972 -- of a specific type. The test for access types is needed to exclude
973 -- cases where the renamed object is a dynamically tagged access
974 -- result, such as occurs in certain expansions.
976 if Is_Tagged_Type
(T
) then
977 Check_Dynamically_Tagged_Expression
983 -- Ada 2005 (AI-230/AI-254): Access renaming
985 else pragma Assert
(Present
(Access_Definition
(N
)));
986 T
:= Access_Definition
988 N
=> Access_Definition
(N
));
992 -- Ada 2005 AI05-105: if the declaration has an anonymous access
993 -- type, the renamed object must also have an anonymous type, and
994 -- this is a name resolution rule. This was implicit in the last part
995 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
998 if not Is_Overloaded
(Nam
) then
999 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
1001 ("expect anonymous access type in object renaming", N
);
1008 Typ
: Entity_Id
:= Empty
;
1009 Seen
: Boolean := False;
1012 Get_First_Interp
(Nam
, I
, It
);
1013 while Present
(It
.Typ
) loop
1015 -- Renaming is ambiguous if more than one candidate
1016 -- interpretation is type-conformant with the context.
1018 if Ekind
(It
.Typ
) = Ekind
(T
) then
1019 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
1022 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
1028 ("ambiguous expression in renaming", Nam
);
1031 elsif Ekind
(T
) = E_Anonymous_Access_Type
1033 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1039 ("ambiguous expression in renaming", Nam
);
1043 if Covers
(T
, It
.Typ
) then
1045 Set_Etype
(Nam
, Typ
);
1046 Set_Is_Overloaded
(Nam
, False);
1050 Get_Next_Interp
(I
, It
);
1057 -- Ada 2005 (AI-231): In the case where the type is defined by an
1058 -- access_definition, the renamed entity shall be of an access-to-
1059 -- constant type if and only if the access_definition defines an
1060 -- access-to-constant type. ARM 8.5.1(4)
1062 if Constant_Present
(Access_Definition
(N
))
1063 and then not Is_Access_Constant
(Etype
(Nam
))
1065 Error_Msg_N
("(Ada 2005): the renamed object is not "
1066 & "access-to-constant (RM 8.5.1(6))", N
);
1068 elsif not Constant_Present
(Access_Definition
(N
))
1069 and then Is_Access_Constant
(Etype
(Nam
))
1071 Error_Msg_N
("(Ada 2005): the renamed object is not "
1072 & "access-to-variable (RM 8.5.1(6))", N
);
1075 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1076 Check_Subtype_Conformant
1077 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1079 elsif not Subtypes_Statically_Match
1080 (Designated_Type
(T
),
1081 Available_View
(Designated_Type
(Etype
(Nam
))))
1084 ("subtype of renamed object does not statically match", N
);
1088 -- Special processing for renaming function return object. Some errors
1089 -- and warnings are produced only for calls that come from source.
1091 if Nkind
(Nam
) = N_Function_Call
then
1094 -- Usage is illegal in Ada 83, but renamings are also introduced
1095 -- during expansion, and error does not apply to those.
1098 if Comes_From_Source
(N
) then
1100 ("(Ada 83) cannot rename function return object", Nam
);
1103 -- In Ada 95, warn for odd case of renaming parameterless function
1104 -- call if this is not a limited type (where this is useful).
1107 if Warn_On_Object_Renames_Function
1108 and then No
(Parameter_Associations
(Nam
))
1109 and then not Is_Limited_Type
(Etype
(Nam
))
1110 and then Comes_From_Source
(Nam
)
1113 ("renaming function result object is suspicious?R?", Nam
);
1115 ("\function & will be called only once?R?", Nam
,
1116 Entity
(Name
(Nam
)));
1117 Error_Msg_N
-- CODEFIX
1118 ("\suggest using an initialized constant "
1119 & "object instead?R?", Nam
);
1125 Check_Constrained_Object
;
1127 -- An object renaming requires an exact match of the type. Class-wide
1128 -- matching is not allowed.
1130 if Is_Class_Wide_Type
(T
)
1131 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1133 Wrong_Type
(Nam
, T
);
1138 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1140 if Nkind
(Nam
) = N_Explicit_Dereference
1141 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1143 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1146 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1147 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1151 -- Ada 2005 (AI-327)
1153 if Ada_Version
>= Ada_2005
1154 and then Nkind
(Nam
) = N_Attribute_Reference
1155 and then Attribute_Name
(Nam
) = Name_Priority
1159 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1162 Nam_Ent
: Entity_Id
;
1165 if Nkind
(Nam
) = N_Attribute_Reference
then
1166 Nam_Ent
:= Entity
(Prefix
(Nam
));
1168 Nam_Ent
:= Entity
(Nam
);
1171 Nam_Decl
:= Parent
(Nam_Ent
);
1173 if Has_Null_Exclusion
(N
)
1174 and then not Has_Null_Exclusion
(Nam_Decl
)
1176 -- Ada 2005 (AI-423): If the object name denotes a generic
1177 -- formal object of a generic unit G, and the object renaming
1178 -- declaration occurs within the body of G or within the body
1179 -- of a generic unit declared within the declarative region
1180 -- of G, then the declaration of the formal object of G must
1181 -- have a null exclusion or a null-excluding subtype.
1183 if Is_Formal_Object
(Nam_Ent
)
1184 and then In_Generic_Scope
(Id
)
1186 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1188 ("renamed formal does not exclude `NULL` "
1189 & "(RM 8.5.1(4.6/2))", N
);
1191 elsif In_Package_Body
(Scope
(Id
)) then
1193 ("formal object does not have a null exclusion"
1194 & "(RM 8.5.1(4.6/2))", N
);
1197 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1198 -- shall exclude null.
1200 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1202 ("renamed object does not exclude `NULL` "
1203 & "(RM 8.5.1(4.6/2))", N
);
1205 -- An instance is illegal if it contains a renaming that
1206 -- excludes null, and the actual does not. The renaming
1207 -- declaration has already indicated that the declaration
1208 -- of the renamed actual in the instance will raise
1209 -- constraint_error.
1211 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1212 and then In_Instance
1214 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1215 and then Nkind
(Expression
(Nam_Decl
)) =
1216 N_Raise_Constraint_Error
1219 ("renamed actual does not exclude `NULL` "
1220 & "(RM 8.5.1(4.6/2))", N
);
1222 -- Finally, if there is a null exclusion, the subtype mark
1223 -- must not be null-excluding.
1225 elsif No
(Access_Definition
(N
))
1226 and then Can_Never_Be_Null
(T
)
1229 ("`NOT NULL` not allowed (& already excludes null)",
1234 elsif Can_Never_Be_Null
(T
)
1235 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1238 ("renamed object does not exclude `NULL` "
1239 & "(RM 8.5.1(4.6/2))", N
);
1241 elsif Has_Null_Exclusion
(N
)
1242 and then No
(Access_Definition
(N
))
1243 and then Can_Never_Be_Null
(T
)
1246 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1251 -- Set the Ekind of the entity, unless it has been set already, as is
1252 -- the case for the iteration object over a container with no variable
1253 -- indexing. In that case it's been marked as a constant, and we do not
1254 -- want to change it to a variable.
1256 if Ekind
(Id
) /= E_Constant
then
1257 Set_Ekind
(Id
, E_Variable
);
1260 -- Initialize the object size and alignment. Note that we used to call
1261 -- Init_Size_Align here, but that's wrong for objects which have only
1262 -- an Esize, not an RM_Size field.
1264 Init_Object_Size_Align
(Id
);
1266 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1269 -- Verify that the renamed entity is an object or a function call. It
1270 -- may have been rewritten in several ways.
1272 elsif Is_Object_Reference
(Nam
) then
1273 if Comes_From_Source
(N
) then
1274 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1276 ("illegal renaming of discriminant-dependent component", Nam
);
1279 -- If the renaming comes from source and the renamed object is a
1280 -- dereference, then mark the prefix as needing debug information,
1281 -- since it might have been rewritten hence internally generated
1282 -- and Debug_Renaming_Declaration will link the renaming to it.
1284 if Nkind
(Nam
) = N_Explicit_Dereference
1285 and then Is_Entity_Name
(Prefix
(Nam
))
1287 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1291 -- A static function call may have been folded into a literal
1293 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1295 -- When expansion is disabled, attribute reference is not rewritten
1296 -- as function call. Otherwise it may be rewritten as a conversion,
1297 -- so check original node.
1299 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1300 and then Is_Function_Attribute_Name
1301 (Attribute_Name
(Original_Node
(Nam
))))
1303 -- Weird but legal, equivalent to renaming a function call. Illegal
1304 -- if the literal is the result of constant-folding an attribute
1305 -- reference that is not a function.
1307 or else (Is_Entity_Name
(Nam
)
1308 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1310 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1312 or else (Nkind
(Nam
) = N_Type_Conversion
1313 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1317 elsif Nkind
(Nam
) = N_Type_Conversion
then
1319 ("renaming of conversion only allowed for tagged types", Nam
);
1321 -- Ada 2005 (AI-327)
1323 elsif Ada_Version
>= Ada_2005
1324 and then Nkind
(Nam
) = N_Attribute_Reference
1325 and then Attribute_Name
(Nam
) = Name_Priority
1329 -- Allow internally generated x'Ref resulting in N_Reference node
1331 elsif Nkind
(Nam
) = N_Reference
then
1335 Error_Msg_N
("expect object name in renaming", Nam
);
1340 if not Is_Variable
(Nam
) then
1341 Set_Ekind
(Id
, E_Constant
);
1342 Set_Never_Set_In_Source
(Id
, True);
1343 Set_Is_True_Constant
(Id
, True);
1346 -- The object renaming declaration may become Ghost if it renames a
1349 if Is_Entity_Name
(Nam
) then
1350 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
1353 -- The entity of the renaming declaration needs to reflect whether the
1354 -- renamed object is volatile. Is_Volatile is set if the renamed object
1355 -- is volatile in the RM legality sense.
1357 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1359 -- Also copy settings of Atomic/Independent/Volatile_Full_Access
1361 if Is_Entity_Name
(Nam
) then
1362 Set_Is_Atomic
(Id
, Is_Atomic
(Entity
(Nam
)));
1363 Set_Is_Independent
(Id
, Is_Independent
(Entity
(Nam
)));
1364 Set_Is_Volatile_Full_Access
(Id
,
1365 Is_Volatile_Full_Access
(Entity
(Nam
)));
1368 -- Treat as volatile if we just set the Volatile flag
1372 -- Or if we are renaming an entity which was marked this way
1374 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1376 or else (Is_Entity_Name
(Nam
)
1377 and then Treat_As_Volatile
(Entity
(Nam
)))
1379 Set_Treat_As_Volatile
(Id
, True);
1382 -- Now make the link to the renamed object
1384 Set_Renamed_Object
(Id
, Nam
);
1386 -- Implementation-defined aspect specifications can appear in a renaming
1387 -- declaration, but not language-defined ones. The call to procedure
1388 -- Analyze_Aspect_Specifications will take care of this error check.
1390 if Has_Aspects
(N
) then
1391 Analyze_Aspect_Specifications
(N
, Id
);
1394 -- Deal with dimensions
1396 Analyze_Dimension
(N
);
1398 -- Restore the original Ghost mode once analysis and expansion have
1402 end Analyze_Object_Renaming
;
1404 ------------------------------
1405 -- Analyze_Package_Renaming --
1406 ------------------------------
1408 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1409 GM
: constant Ghost_Mode_Type
:= Ghost_Mode
;
1411 procedure Restore_Globals
;
1412 -- Restore the values of all saved global variables
1414 ---------------------
1415 -- Restore_Globals --
1416 ---------------------
1418 procedure Restore_Globals
is
1421 end Restore_Globals
;
1425 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1429 -- Start of processing for Analyze_Package_Renaming
1432 if Name
(N
) = Error
then
1436 -- The package renaming declaration may be subject to pragma Ghost with
1437 -- policy Ignore. Set the mode now to ensure that any nodes generated
1438 -- during analysis and expansion are properly flagged as ignored Ghost.
1442 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1444 Check_Text_IO_Special_Unit
(Name
(N
));
1446 if Current_Scope
/= Standard_Standard
then
1447 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1453 if Is_Entity_Name
(Name
(N
)) then
1454 Old_P
:= Entity
(Name
(N
));
1459 if Etype
(Old_P
) = Any_Type
then
1460 Error_Msg_N
("expect package name in renaming", Name
(N
));
1462 elsif Ekind
(Old_P
) /= E_Package
1463 and then not (Ekind
(Old_P
) = E_Generic_Package
1464 and then In_Open_Scopes
(Old_P
))
1466 if Ekind
(Old_P
) = E_Generic_Package
then
1468 ("generic package cannot be renamed as a package", Name
(N
));
1470 Error_Msg_Sloc
:= Sloc
(Old_P
);
1472 ("expect package name in renaming, found& declared#",
1476 -- Set basic attributes to minimize cascaded errors
1478 Set_Ekind
(New_P
, E_Package
);
1479 Set_Etype
(New_P
, Standard_Void_Type
);
1481 -- Here for OK package renaming
1484 -- Entities in the old package are accessible through the renaming
1485 -- entity. The simplest implementation is to have both packages share
1488 Set_Ekind
(New_P
, E_Package
);
1489 Set_Etype
(New_P
, Standard_Void_Type
);
1491 if Present
(Renamed_Object
(Old_P
)) then
1492 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1494 Set_Renamed_Object
(New_P
, Old_P
);
1497 Set_Has_Completion
(New_P
);
1499 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1500 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1501 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1502 Check_Library_Unit_Renaming
(N
, Old_P
);
1503 Generate_Reference
(Old_P
, Name
(N
));
1505 -- The package renaming declaration may become Ghost if it renames a
1508 Mark_Renaming_As_Ghost
(N
, Old_P
);
1510 -- If the renaming is in the visible part of a package, then we set
1511 -- Renamed_In_Spec for the renamed package, to prevent giving
1512 -- warnings about no entities referenced. Such a warning would be
1513 -- overenthusiastic, since clients can see entities in the renamed
1514 -- package via the visible package renaming.
1517 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1519 if Ekind
(Ent
) = E_Package
1520 and then not In_Private_Part
(Ent
)
1521 and then In_Extended_Main_Source_Unit
(N
)
1522 and then Ekind
(Old_P
) = E_Package
1524 Set_Renamed_In_Spec
(Old_P
);
1528 -- If this is the renaming declaration of a package instantiation
1529 -- within itself, it is the declaration that ends the list of actuals
1530 -- for the instantiation. At this point, the subtypes that rename
1531 -- the actuals are flagged as generic, to avoid spurious ambiguities
1532 -- if the actuals for two distinct formals happen to coincide. If
1533 -- the actual is a private type, the subtype has a private completion
1534 -- that is flagged in the same fashion.
1536 -- Resolution is identical to what is was in the original generic.
1537 -- On exit from the generic instance, these are turned into regular
1538 -- subtypes again, so they are compatible with types in their class.
1540 if not Is_Generic_Instance
(Old_P
) then
1544 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1547 if Nkind
(Spec
) = N_Package_Specification
1548 and then Present
(Generic_Parent
(Spec
))
1549 and then Old_P
= Current_Scope
1550 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1556 E
:= First_Entity
(Old_P
);
1557 while Present
(E
) and then E
/= New_P
loop
1559 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1561 Set_Is_Generic_Actual_Type
(E
);
1563 if Is_Private_Type
(E
)
1564 and then Present
(Full_View
(E
))
1566 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1576 -- Implementation-defined aspect specifications can appear in a renaming
1577 -- declaration, but not language-defined ones. The call to procedure
1578 -- Analyze_Aspect_Specifications will take care of this error check.
1580 if Has_Aspects
(N
) then
1581 Analyze_Aspect_Specifications
(N
, New_P
);
1585 end Analyze_Package_Renaming
;
1587 -------------------------------
1588 -- Analyze_Renamed_Character --
1589 -------------------------------
1591 procedure Analyze_Renamed_Character
1596 C
: constant Node_Id
:= Name
(N
);
1599 if Ekind
(New_S
) = E_Function
then
1600 Resolve
(C
, Etype
(New_S
));
1603 Check_Frozen_Renaming
(N
, New_S
);
1607 Error_Msg_N
("character literal can only be renamed as function", N
);
1609 end Analyze_Renamed_Character
;
1611 ---------------------------------
1612 -- Analyze_Renamed_Dereference --
1613 ---------------------------------
1615 procedure Analyze_Renamed_Dereference
1620 Nam
: constant Node_Id
:= Name
(N
);
1621 P
: constant Node_Id
:= Prefix
(Nam
);
1627 if not Is_Overloaded
(P
) then
1628 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1629 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1631 Error_Msg_N
("designated type does not match specification", P
);
1640 Get_First_Interp
(Nam
, Ind
, It
);
1642 while Present
(It
.Nam
) loop
1644 if Ekind
(It
.Nam
) = E_Subprogram_Type
1645 and then Type_Conformant
(It
.Nam
, New_S
)
1647 if Typ
/= Any_Id
then
1648 Error_Msg_N
("ambiguous renaming", P
);
1655 Get_Next_Interp
(Ind
, It
);
1658 if Typ
= Any_Type
then
1659 Error_Msg_N
("designated type does not match specification", P
);
1664 Check_Frozen_Renaming
(N
, New_S
);
1668 end Analyze_Renamed_Dereference
;
1670 ---------------------------
1671 -- Analyze_Renamed_Entry --
1672 ---------------------------
1674 procedure Analyze_Renamed_Entry
1679 Nam
: constant Node_Id
:= Name
(N
);
1680 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1681 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1685 if Entity
(Sel
) = Any_Id
then
1687 -- Selector is undefined on prefix. Error emitted already
1689 Set_Has_Completion
(New_S
);
1693 -- Otherwise find renamed entity and build body of New_S as a call to it
1695 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1697 if Old_S
= Any_Id
then
1698 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1701 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1702 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1703 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1706 -- Only mode conformance required for a renaming_as_declaration
1708 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1711 Inherit_Renamed_Profile
(New_S
, Old_S
);
1713 -- The prefix can be an arbitrary expression that yields a task or
1714 -- protected object, so it must be resolved.
1716 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1719 Set_Convention
(New_S
, Convention
(Old_S
));
1720 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1722 -- AI05-0225: If the renamed entity is a procedure or entry of a
1723 -- protected object, the target object must be a variable.
1725 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1726 and then Ekind
(New_S
) = E_Procedure
1727 and then not Is_Variable
(Prefix
(Nam
))
1731 ("target object of protected operation used as actual for "
1732 & "formal procedure must be a variable", Nam
);
1735 ("target object of protected operation renamed as procedure, "
1736 & "must be a variable", Nam
);
1741 Check_Frozen_Renaming
(N
, New_S
);
1743 end Analyze_Renamed_Entry
;
1745 -----------------------------------
1746 -- Analyze_Renamed_Family_Member --
1747 -----------------------------------
1749 procedure Analyze_Renamed_Family_Member
1754 Nam
: constant Node_Id
:= Name
(N
);
1755 P
: constant Node_Id
:= Prefix
(Nam
);
1759 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1760 or else (Nkind
(P
) = N_Selected_Component
1761 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1763 if Is_Entity_Name
(P
) then
1764 Old_S
:= Entity
(P
);
1766 Old_S
:= Entity
(Selector_Name
(P
));
1769 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1770 Error_Msg_N
("entry family does not match specification", N
);
1773 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1774 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1775 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1779 Error_Msg_N
("no entry family matches specification", N
);
1782 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1785 Check_Frozen_Renaming
(N
, New_S
);
1787 end Analyze_Renamed_Family_Member
;
1789 -----------------------------------------
1790 -- Analyze_Renamed_Primitive_Operation --
1791 -----------------------------------------
1793 procedure Analyze_Renamed_Primitive_Operation
1802 Ctyp
: Conformance_Type
) return Boolean;
1803 -- Verify that the signatures of the renamed entity and the new entity
1804 -- match. The first formal of the renamed entity is skipped because it
1805 -- is the target object in any subsequent call.
1813 Ctyp
: Conformance_Type
) return Boolean
1819 if Ekind
(Subp
) /= Ekind
(New_S
) then
1823 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1824 New_F
:= First_Formal
(New_S
);
1825 while Present
(Old_F
) and then Present
(New_F
) loop
1826 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1830 if Ctyp
>= Mode_Conformant
1831 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1836 Next_Formal
(New_F
);
1837 Next_Formal
(Old_F
);
1843 -- Start of processing for Analyze_Renamed_Primitive_Operation
1846 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1847 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1849 if not Conforms
(Old_S
, Type_Conformant
) then
1854 -- Find the operation that matches the given signature
1862 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1864 while Present
(It
.Nam
) loop
1865 if Conforms
(It
.Nam
, Type_Conformant
) then
1869 Get_Next_Interp
(Ind
, It
);
1874 if Old_S
= Any_Id
then
1875 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1879 if not Conforms
(Old_S
, Subtype_Conformant
) then
1880 Error_Msg_N
("subtype conformance error in renaming", N
);
1883 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1884 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1887 -- Only mode conformance required for a renaming_as_declaration
1889 if not Conforms
(Old_S
, Mode_Conformant
) then
1890 Error_Msg_N
("mode conformance error in renaming", N
);
1893 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1894 -- view of a subprogram is intrinsic, because the compiler has
1895 -- to generate a wrapper for any call to it. If the name in a
1896 -- subprogram renaming is a prefixed view, the entity is thus
1897 -- intrinsic, and 'Access cannot be applied to it.
1899 Set_Convention
(New_S
, Convention_Intrinsic
);
1902 -- Inherit_Renamed_Profile (New_S, Old_S);
1904 -- The prefix can be an arbitrary expression that yields an
1905 -- object, so it must be resolved.
1907 Resolve
(Prefix
(Name
(N
)));
1909 end Analyze_Renamed_Primitive_Operation
;
1911 ---------------------------------
1912 -- Analyze_Subprogram_Renaming --
1913 ---------------------------------
1915 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1916 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1917 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1918 Nam
: constant Node_Id
:= Name
(N
);
1919 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1920 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1921 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1922 Spec
: constant Node_Id
:= Specification
(N
);
1924 Old_S
: Entity_Id
:= Empty
;
1925 Rename_Spec
: Entity_Id
;
1927 procedure Build_Class_Wide_Wrapper
1928 (Ren_Id
: out Entity_Id
;
1929 Wrap_Id
: out Entity_Id
);
1930 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1931 -- type with unknown discriminants and a generic primitive operation of
1932 -- the said type with a box require special processing when the actual
1933 -- is a class-wide type:
1936 -- type Formal_Typ (<>) is private;
1937 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1938 -- package Gen is ...
1940 -- package Inst is new Gen (Actual_Typ'Class);
1942 -- In this case the general renaming mechanism used in the prologue of
1943 -- an instance no longer applies:
1945 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1947 -- The above is replaced the following wrapper/renaming combination:
1949 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1951 -- Prim_Op (Param); -- primitive
1954 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1956 -- This transformation applies only if there is no explicit visible
1957 -- class-wide operation at the point of the instantiation. Ren_Id is
1958 -- the entity of the renaming declaration. Wrap_Id is the entity of
1959 -- the generated class-wide wrapper (or Any_Id).
1961 procedure Check_Null_Exclusion
1964 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1965 -- following AI rules:
1967 -- If Ren is a renaming of a formal subprogram and one of its
1968 -- parameters has a null exclusion, then the corresponding formal
1969 -- in Sub must also have one. Otherwise the subtype of the Sub's
1970 -- formal parameter must exclude null.
1972 -- If Ren is a renaming of a formal function and its return
1973 -- profile has a null exclusion, then Sub's return profile must
1974 -- have one. Otherwise the subtype of Sub's return profile must
1977 procedure Freeze_Actual_Profile
;
1978 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1979 -- types: a callable entity freezes its profile, unless it has an
1980 -- incomplete untagged formal (RM 13.14(10.2/3)).
1982 function Has_Class_Wide_Actual
return Boolean;
1983 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1984 -- defaulted formal subprogram where the actual for the controlling
1985 -- formal type is class-wide.
1987 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1988 -- Find renamed entity when the declaration is a renaming_as_body and
1989 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1990 -- rule that a renaming_as_body is illegal if the declaration occurs
1991 -- before the subprogram it completes is frozen, and renaming indirectly
1992 -- renames the subprogram itself.(Defect Report 8652/0027).
1994 ------------------------------
1995 -- Build_Class_Wide_Wrapper --
1996 ------------------------------
1998 procedure Build_Class_Wide_Wrapper
1999 (Ren_Id
: out Entity_Id
;
2000 Wrap_Id
: out Entity_Id
)
2002 Loc
: constant Source_Ptr
:= Sloc
(N
);
2005 (Subp_Id
: Entity_Id
;
2006 Params
: List_Id
) return Node_Id
;
2007 -- Create a dispatching call to invoke routine Subp_Id with actuals
2008 -- built from the parameter specifications of list Params.
2010 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
2011 -- Create a subprogram specification based on the subprogram profile
2014 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
2015 -- Find a primitive subprogram of type Typ which matches the profile
2016 -- of the renaming declaration.
2018 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
2019 -- Emit a continuation error message suggesting subprogram Subp_Id as
2020 -- a possible interpretation.
2022 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
2023 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
2026 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
2027 -- Determine whether subprogram Subp_Id is a suitable candidate for
2028 -- the role of a wrapped subprogram.
2035 (Subp_Id
: Entity_Id
;
2036 Params
: List_Id
) return Node_Id
2038 Actuals
: constant List_Id
:= New_List
;
2039 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
2043 -- Build the actual parameters of the call
2045 Formal
:= First
(Params
);
2046 while Present
(Formal
) loop
2048 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2053 -- return Subp_Id (Actuals);
2055 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2057 Make_Simple_Return_Statement
(Loc
,
2059 Make_Function_Call
(Loc
,
2061 Parameter_Associations
=> Actuals
));
2064 -- Subp_Id (Actuals);
2068 Make_Procedure_Call_Statement
(Loc
,
2070 Parameter_Associations
=> Actuals
);
2078 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2079 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2080 Spec_Id
: constant Entity_Id
:=
2081 Make_Defining_Identifier
(Loc
,
2082 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2085 if Ekind
(Formal_Spec
) = E_Procedure
then
2087 Make_Procedure_Specification
(Loc
,
2088 Defining_Unit_Name
=> Spec_Id
,
2089 Parameter_Specifications
=> Params
);
2092 Make_Function_Specification
(Loc
,
2093 Defining_Unit_Name
=> Spec_Id
,
2094 Parameter_Specifications
=> Params
,
2095 Result_Definition
=>
2096 New_Copy_Tree
(Result_Definition
(Spec
)));
2100 --------------------
2101 -- Find_Primitive --
2102 --------------------
2104 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2105 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2106 -- Given a specification Spec, replace all class-wide parameter
2107 -- types with reference to type Typ.
2109 -----------------------------
2110 -- Replace_Parameter_Types --
2111 -----------------------------
2113 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2115 Formal_Id
: Entity_Id
;
2116 Formal_Typ
: Node_Id
;
2119 Formal
:= First
(Parameter_Specifications
(Spec
));
2120 while Present
(Formal
) loop
2121 Formal_Id
:= Defining_Identifier
(Formal
);
2122 Formal_Typ
:= Parameter_Type
(Formal
);
2124 -- Create a new entity for each class-wide formal to prevent
2125 -- aliasing with the original renaming. Replace the type of
2126 -- such a parameter with the candidate type.
2128 if Nkind
(Formal_Typ
) = N_Identifier
2129 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2131 Set_Defining_Identifier
(Formal
,
2132 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2134 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2139 end Replace_Parameter_Types
;
2143 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2144 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2145 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2146 Subp_Id
: Entity_Id
;
2148 -- Start of processing for Find_Primitive
2151 -- Each attempt to find a suitable primitive of a particular type
2152 -- operates on its own copy of the original renaming. As a result
2153 -- the original renaming is kept decoration and side-effect free.
2155 -- Inherit the overloaded status of the renamed subprogram name
2157 if Is_Overloaded
(Nam
) then
2158 Set_Is_Overloaded
(Alt_Nam
);
2159 Save_Interps
(Nam
, Alt_Nam
);
2162 -- The copied renaming is hidden from visibility to prevent the
2163 -- pollution of the enclosing context.
2165 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2167 -- The types of all class-wide parameters must be changed to the
2170 Replace_Parameter_Types
(Alt_Spec
);
2172 -- Try to find a suitable primitive which matches the altered
2173 -- profile of the renaming specification.
2178 Nam
=> Name
(Alt_Ren
),
2179 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2180 Is_Actual
=> Is_Actual
);
2182 -- Do not return Any_Id if the resolion of the altered profile
2183 -- failed as this complicates further checks on the caller side,
2184 -- return Empty instead.
2186 if Subp_Id
= Any_Id
then
2193 --------------------------
2194 -- Interpretation_Error --
2195 --------------------------
2197 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2199 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2201 if Is_Internal
(Subp_Id
) then
2203 ("\\possible interpretation: predefined & #",
2207 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2209 end Interpretation_Error
;
2211 ---------------------------
2212 -- Is_Intrinsic_Equality --
2213 ---------------------------
2215 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2218 Ekind
(Subp_Id
) = E_Operator
2219 and then Chars
(Subp_Id
) = Name_Op_Eq
2220 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2221 end Is_Intrinsic_Equality
;
2223 ---------------------------
2224 -- Is_Suitable_Candidate --
2225 ---------------------------
2227 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2229 if No
(Subp_Id
) then
2232 -- An intrinsic subprogram is never a good candidate. This is an
2233 -- indication of a missing primitive, either defined directly or
2234 -- inherited from a parent tagged type.
2236 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2242 end Is_Suitable_Candidate
;
2246 Actual_Typ
: Entity_Id
:= Empty
;
2247 -- The actual class-wide type for Formal_Typ
2249 CW_Prim_OK
: Boolean;
2250 CW_Prim_Op
: Entity_Id
;
2251 -- The class-wide subprogram (if available) which corresponds to the
2252 -- renamed generic formal subprogram.
2254 Formal_Typ
: Entity_Id
:= Empty
;
2255 -- The generic formal type with unknown discriminants
2257 Root_Prim_OK
: Boolean;
2258 Root_Prim_Op
: Entity_Id
;
2259 -- The root type primitive (if available) which corresponds to the
2260 -- renamed generic formal subprogram.
2262 Root_Typ
: Entity_Id
:= Empty
;
2263 -- The root type of Actual_Typ
2265 Body_Decl
: Node_Id
;
2267 Prim_Op
: Entity_Id
;
2268 Spec_Decl
: Node_Id
;
2270 -- Start of processing for Build_Class_Wide_Wrapper
2273 -- Analyze the specification of the renaming in case the generation
2274 -- of the class-wide wrapper fails.
2276 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2279 -- Do not attempt to build a wrapper if the renaming is in error
2281 if Error_Posted
(Nam
) then
2285 -- Analyze the renamed name, but do not resolve it. The resolution is
2286 -- completed once a suitable subprogram is found.
2290 -- When the renamed name denotes the intrinsic operator equals, the
2291 -- name must be treated as overloaded. This allows for a potential
2292 -- match against the root type's predefined equality function.
2294 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2295 Set_Is_Overloaded
(Nam
);
2296 Collect_Interps
(Nam
);
2299 -- Step 1: Find the generic formal type with unknown discriminants
2300 -- and its corresponding class-wide actual type from the renamed
2301 -- generic formal subprogram.
2303 Formal
:= First_Formal
(Formal_Spec
);
2304 while Present
(Formal
) loop
2305 if Has_Unknown_Discriminants
(Etype
(Formal
))
2306 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2307 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2309 Formal_Typ
:= Etype
(Formal
);
2310 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2311 Root_Typ
:= Etype
(Actual_Typ
);
2315 Next_Formal
(Formal
);
2318 -- The specification of the generic formal subprogram should always
2319 -- contain a formal type with unknown discriminants whose actual is
2320 -- a class-wide type, otherwise this indicates a failure in routine
2321 -- Has_Class_Wide_Actual.
2323 pragma Assert
(Present
(Formal_Typ
));
2325 -- Step 2: Find the proper class-wide subprogram or primitive which
2326 -- corresponds to the renamed generic formal subprogram.
2328 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2329 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2330 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2331 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2333 -- The class-wide actual type has two subprograms which correspond to
2334 -- the renamed generic formal subprogram:
2336 -- with procedure Prim_Op (Param : Formal_Typ);
2338 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2339 -- procedure Prim_Op (Param : Actual_Typ'Class);
2341 -- Even though the declaration of the two subprograms is legal, a
2342 -- call to either one is ambiguous and therefore illegal.
2344 if CW_Prim_OK
and Root_Prim_OK
then
2346 -- A user-defined primitive has precedence over a predefined one
2348 if Is_Internal
(CW_Prim_Op
)
2349 and then not Is_Internal
(Root_Prim_Op
)
2351 Prim_Op
:= Root_Prim_Op
;
2353 elsif Is_Internal
(Root_Prim_Op
)
2354 and then not Is_Internal
(CW_Prim_Op
)
2356 Prim_Op
:= CW_Prim_Op
;
2358 elsif CW_Prim_Op
= Root_Prim_Op
then
2359 Prim_Op
:= Root_Prim_Op
;
2361 -- Otherwise both candidate subprograms are user-defined and
2366 ("ambiguous actual for generic subprogram &",
2368 Interpretation_Error
(Root_Prim_Op
);
2369 Interpretation_Error
(CW_Prim_Op
);
2373 elsif CW_Prim_OK
and not Root_Prim_OK
then
2374 Prim_Op
:= CW_Prim_Op
;
2376 elsif not CW_Prim_OK
and Root_Prim_OK
then
2377 Prim_Op
:= Root_Prim_Op
;
2379 -- An intrinsic equality may act as a suitable candidate in the case
2380 -- of a null type extension where the parent's equality is hidden. A
2381 -- call to an intrinsic equality is expanded as dispatching.
2383 elsif Present
(Root_Prim_Op
)
2384 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2386 Prim_Op
:= Root_Prim_Op
;
2388 -- Otherwise there are no candidate subprograms. Let the caller
2389 -- diagnose the error.
2395 -- At this point resolution has taken place and the name is no longer
2396 -- overloaded. Mark the primitive as referenced.
2398 Set_Is_Overloaded
(Name
(N
), False);
2399 Set_Referenced
(Prim_Op
);
2401 -- Step 3: Create the declaration and the body of the wrapper, insert
2402 -- all the pieces into the tree.
2405 Make_Subprogram_Declaration
(Loc
,
2406 Specification
=> Build_Spec
(Ren_Id
));
2407 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2409 -- If the operator carries an Eliminated pragma, indicate that the
2410 -- wrapper is also to be eliminated, to prevent spurious error when
2411 -- using gnatelim on programs that include box-initialization of
2412 -- equality operators.
2414 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2415 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2418 Make_Subprogram_Body
(Loc
,
2419 Specification
=> Build_Spec
(Ren_Id
),
2420 Declarations
=> New_List
,
2421 Handled_Statement_Sequence
=>
2422 Make_Handled_Sequence_Of_Statements
(Loc
,
2423 Statements
=> New_List
(
2425 (Subp_Id
=> Prim_Op
,
2427 Parameter_Specifications
2428 (Specification
(Spec_Decl
))))));
2430 -- The generated body does not freeze and must be analyzed when the
2431 -- class-wide wrapper is frozen. The body is only needed if expansion
2434 if Expander_Active
then
2435 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2438 -- Step 4: The subprogram renaming aliases the wrapper
2440 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2441 end Build_Class_Wide_Wrapper
;
2443 --------------------------
2444 -- Check_Null_Exclusion --
2445 --------------------------
2447 procedure Check_Null_Exclusion
2451 Ren_Formal
: Entity_Id
;
2452 Sub_Formal
: Entity_Id
;
2457 Ren_Formal
:= First_Formal
(Ren
);
2458 Sub_Formal
:= First_Formal
(Sub
);
2459 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2460 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2462 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2463 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2466 ("`NOT NULL` required for parameter &",
2467 Parent
(Sub_Formal
), Sub_Formal
);
2470 Next_Formal
(Ren_Formal
);
2471 Next_Formal
(Sub_Formal
);
2474 -- Return profile check
2476 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2477 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2478 and then Has_Null_Exclusion
(Parent
(Ren
))
2479 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2480 or else Can_Never_Be_Null
(Etype
(Sub
)))
2483 ("return must specify `NOT NULL`",
2484 Result_Definition
(Parent
(Sub
)));
2486 end Check_Null_Exclusion
;
2488 ---------------------------
2489 -- Freeze_Actual_Profile --
2490 ---------------------------
2492 procedure Freeze_Actual_Profile
is
2494 Has_Untagged_Inc
: Boolean;
2495 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2498 if Ada_Version
>= Ada_2012
then
2499 F
:= First_Formal
(Formal_Spec
);
2500 Has_Untagged_Inc
:= False;
2501 while Present
(F
) loop
2502 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2503 and then not Is_Tagged_Type
(Etype
(F
))
2505 Has_Untagged_Inc
:= True;
2509 F
:= Next_Formal
(F
);
2512 if Ekind
(Formal_Spec
) = E_Function
2513 and then not Is_Tagged_Type
(Etype
(Formal_Spec
))
2515 Has_Untagged_Inc
:= True;
2518 if not Has_Untagged_Inc
then
2519 F
:= First_Formal
(Old_S
);
2520 while Present
(F
) loop
2521 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2523 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2524 and then No
(Underlying_Type
(Etype
(F
)))
2526 -- Exclude generic types, or types derived from them.
2527 -- They will be frozen in the enclosing instance.
2529 if Is_Generic_Type
(Etype
(F
))
2530 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2534 -- A limited view of a type declared elsewhere needs no
2535 -- freezing actions.
2537 elsif From_Limited_With
(Etype
(F
)) then
2542 ("type& must be frozen before this point",
2543 Instantiation_Node
, Etype
(F
));
2547 F
:= Next_Formal
(F
);
2551 end Freeze_Actual_Profile
;
2553 ---------------------------
2554 -- Has_Class_Wide_Actual --
2555 ---------------------------
2557 function Has_Class_Wide_Actual
return Boolean is
2559 Formal_Typ
: Entity_Id
;
2563 Formal
:= First_Formal
(Formal_Spec
);
2564 while Present
(Formal
) loop
2565 Formal_Typ
:= Etype
(Formal
);
2567 if Has_Unknown_Discriminants
(Formal_Typ
)
2568 and then not Is_Class_Wide_Type
(Formal_Typ
)
2569 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2574 Next_Formal
(Formal
);
2579 end Has_Class_Wide_Actual
;
2581 -------------------------
2582 -- Original_Subprogram --
2583 -------------------------
2585 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2586 Orig_Decl
: Node_Id
;
2587 Orig_Subp
: Entity_Id
;
2590 -- First case: renamed entity is itself a renaming
2592 if Present
(Alias
(Subp
)) then
2593 return Alias
(Subp
);
2595 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2596 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2598 -- Check if renamed entity is a renaming_as_body
2601 Unit_Declaration_Node
2602 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2604 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2605 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2607 if Orig_Subp
= Rename_Spec
then
2609 -- Circularity detected
2614 return (Original_Subprogram
(Orig_Subp
));
2622 end Original_Subprogram
;
2626 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2627 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2628 -- defaulted formal subprogram when the actual for a related formal
2629 -- type is class-wide.
2631 GM
: constant Ghost_Mode_Type
:= Ghost_Mode
;
2632 Inst_Node
: Node_Id
:= Empty
;
2635 -- Start of processing for Analyze_Subprogram_Renaming
2638 -- The subprogram renaming declaration may be subject to pragma Ghost
2639 -- with policy Ignore. Set the mode now to ensure that any nodes
2640 -- generated during analysis and expansion are properly flagged as
2645 -- We must test for the attribute renaming case before the Analyze
2646 -- call because otherwise Sem_Attr will complain that the attribute
2647 -- is missing an argument when it is analyzed.
2649 if Nkind
(Nam
) = N_Attribute_Reference
then
2651 -- In the case of an abstract formal subprogram association, rewrite
2652 -- an actual given by a stream attribute as the name of the
2653 -- corresponding stream primitive of the type.
2655 -- In a generic context the stream operations are not generated, and
2656 -- this must be treated as a normal attribute reference, to be
2657 -- expanded in subsequent instantiations.
2660 and then Is_Abstract_Subprogram
(Formal_Spec
)
2661 and then Expander_Active
2664 Stream_Prim
: Entity_Id
;
2665 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2668 -- The class-wide forms of the stream attributes are not
2669 -- primitive dispatching operations (even though they
2670 -- internally dispatch to a stream attribute).
2672 if Is_Class_Wide_Type
(Prefix_Type
) then
2674 ("attribute must be a primitive dispatching operation",
2679 -- Retrieve the primitive subprogram associated with the
2680 -- attribute. This can only be a stream attribute, since those
2681 -- are the only ones that are dispatching (and the actual for
2682 -- an abstract formal subprogram must be dispatching
2685 case Attribute_Name
(Nam
) is
2688 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2691 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2694 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2697 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2700 ("attribute must be a primitive"
2701 & " dispatching operation", Nam
);
2705 -- If no operation was found, and the type is limited,
2706 -- the user should have defined one.
2708 if No
(Stream_Prim
) then
2709 if Is_Limited_Type
(Prefix_Type
) then
2711 ("stream operation not defined for type&",
2715 -- Otherwise, compiler should have generated default
2718 raise Program_Error
;
2722 -- Rewrite the attribute into the name of its corresponding
2723 -- primitive dispatching subprogram. We can then proceed with
2724 -- the usual processing for subprogram renamings.
2727 Prim_Name
: constant Node_Id
:=
2728 Make_Identifier
(Sloc
(Nam
),
2729 Chars
=> Chars
(Stream_Prim
));
2731 Set_Entity
(Prim_Name
, Stream_Prim
);
2732 Rewrite
(Nam
, Prim_Name
);
2737 -- Normal processing for a renaming of an attribute
2740 Attribute_Renaming
(N
);
2745 -- Check whether this declaration corresponds to the instantiation
2746 -- of a formal subprogram.
2748 -- If this is an instantiation, the corresponding actual is frozen and
2749 -- error messages can be made more precise. If this is a default
2750 -- subprogram, the entity is already established in the generic, and is
2751 -- not retrieved by visibility. If it is a default with a box, the
2752 -- candidate interpretations, if any, have been collected when building
2753 -- the renaming declaration. If overloaded, the proper interpretation is
2754 -- determined in Find_Renamed_Entity. If the entity is an operator,
2755 -- Find_Renamed_Entity applies additional visibility checks.
2758 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2760 -- Check whether the renaming is for a defaulted actual subprogram
2761 -- with a class-wide actual.
2763 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2764 -- is an external axiomatization on the package.
2767 and then Box_Present
(Inst_Node
)
2771 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2773 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2775 elsif Is_Entity_Name
(Nam
)
2776 and then Present
(Entity
(Nam
))
2777 and then not Comes_From_Source
(Nam
)
2778 and then not Is_Overloaded
(Nam
)
2780 Old_S
:= Entity
(Nam
);
2781 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2785 if Ekind
(Entity
(Nam
)) = E_Operator
then
2789 if Box_Present
(Inst_Node
) then
2790 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2792 -- If there is an immediately visible homonym of the operator
2793 -- and the declaration has a default, this is worth a warning
2794 -- because the user probably did not intend to get the pre-
2795 -- defined operator, visible in the generic declaration. To
2796 -- find if there is an intended candidate, analyze the renaming
2797 -- again in the current context.
2799 elsif Scope
(Old_S
) = Standard_Standard
2800 and then Present
(Default_Name
(Inst_Node
))
2803 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2807 Set_Entity
(Name
(Decl
), Empty
);
2808 Analyze
(Name
(Decl
));
2810 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2813 and then In_Open_Scopes
(Scope
(Hidden
))
2814 and then Is_Immediately_Visible
(Hidden
)
2815 and then Comes_From_Source
(Hidden
)
2816 and then Hidden
/= Old_S
2818 Error_Msg_Sloc
:= Sloc
(Hidden
);
2819 Error_Msg_N
("default subprogram is resolved " &
2820 "in the generic declaration " &
2821 "(RM 12.6(17))??", N
);
2822 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2830 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2834 -- Renamed entity must be analyzed first, to avoid being hidden by
2835 -- new name (which might be the same in a generic instance).
2839 -- The renaming defines a new overloaded entity, which is analyzed
2840 -- like a subprogram declaration.
2842 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2845 if Current_Scope
/= Standard_Standard
then
2846 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2849 -- Set SPARK mode from current context
2851 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2852 Set_SPARK_Pragma_Inherited
(New_S
, True);
2854 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2856 -- Case of Renaming_As_Body
2858 if Present
(Rename_Spec
) then
2860 -- Renaming declaration is the completion of the declaration of
2861 -- Rename_Spec. We build an actual body for it at the freezing point.
2863 Set_Corresponding_Spec
(N
, Rename_Spec
);
2865 -- Deal with special case of stream functions of abstract types
2868 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2869 N_Abstract_Subprogram_Declaration
2871 -- Input stream functions are abstract if the object type is
2872 -- abstract. Similarly, all default stream functions for an
2873 -- interface type are abstract. However, these subprograms may
2874 -- receive explicit declarations in representation clauses, making
2875 -- the attribute subprograms usable as defaults in subsequent
2877 -- In this case we rewrite the declaration to make the subprogram
2878 -- non-abstract. We remove the previous declaration, and insert
2879 -- the new one at the point of the renaming, to prevent premature
2880 -- access to unfrozen types. The new declaration reuses the
2881 -- specification of the previous one, and must not be analyzed.
2884 (Is_Primitive
(Entity
(Nam
))
2886 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2888 Old_Decl
: constant Node_Id
:=
2889 Unit_Declaration_Node
(Rename_Spec
);
2890 New_Decl
: constant Node_Id
:=
2891 Make_Subprogram_Declaration
(Sloc
(N
),
2893 Relocate_Node
(Specification
(Old_Decl
)));
2896 Insert_After
(N
, New_Decl
);
2897 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2898 Set_Analyzed
(New_Decl
);
2902 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2904 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2905 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2908 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2909 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2910 Set_Public_Status
(New_S
);
2912 -- The specification does not introduce new formals, but only
2913 -- repeats the formals of the original subprogram declaration.
2914 -- For cross-reference purposes, and for refactoring tools, we
2915 -- treat the formals of the renaming declaration as body formals.
2917 Reference_Body_Formals
(Rename_Spec
, New_S
);
2919 -- Indicate that the entity in the declaration functions like the
2920 -- corresponding body, and is not a new entity. The body will be
2921 -- constructed later at the freeze point, so indicate that the
2922 -- completion has not been seen yet.
2924 Set_Ekind
(New_S
, E_Subprogram_Body
);
2925 New_S
:= Rename_Spec
;
2926 Set_Has_Completion
(Rename_Spec
, False);
2928 -- Ada 2005: check overriding indicator
2930 if Present
(Overridden_Operation
(Rename_Spec
)) then
2931 if Must_Not_Override
(Specification
(N
)) then
2933 ("subprogram& overrides inherited operation",
2936 Style_Check
and then not Must_Override
(Specification
(N
))
2938 Style
.Missing_Overriding
(N
, Rename_Spec
);
2941 elsif Must_Override
(Specification
(N
)) then
2942 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2945 -- Normal subprogram renaming (not renaming as body)
2948 Generate_Definition
(New_S
);
2949 New_Overloaded_Entity
(New_S
);
2951 if Is_Entity_Name
(Nam
)
2952 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2956 Check_Delayed_Subprogram
(New_S
);
2960 -- There is no need for elaboration checks on the new entity, which may
2961 -- be called before the next freezing point where the body will appear.
2962 -- Elaboration checks refer to the real entity, not the one created by
2963 -- the renaming declaration.
2965 Set_Kill_Elaboration_Checks
(New_S
, True);
2967 -- If we had a previous error, indicate a completely is present to stop
2968 -- junk cascaded messages, but don't take any further action.
2970 if Etype
(Nam
) = Any_Type
then
2971 Set_Has_Completion
(New_S
);
2974 -- Case where name has the form of a selected component
2976 elsif Nkind
(Nam
) = N_Selected_Component
then
2978 -- A name which has the form A.B can designate an entry of task A, a
2979 -- protected operation of protected object A, or finally a primitive
2980 -- operation of object A. In the later case, A is an object of some
2981 -- tagged type, or an access type that denotes one such. To further
2982 -- distinguish these cases, note that the scope of a task entry or
2983 -- protected operation is type of the prefix.
2985 -- The prefix could be an overloaded function call that returns both
2986 -- kinds of operations. This overloading pathology is left to the
2987 -- dedicated reader ???
2990 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2998 and then Is_Tagged_Type
(Designated_Type
(T
))))
2999 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
3001 Analyze_Renamed_Primitive_Operation
3002 (N
, New_S
, Present
(Rename_Spec
));
3006 -- Renamed entity is an entry or protected operation. For those
3007 -- cases an explicit body is built (at the point of freezing of
3008 -- this entity) that contains a call to the renamed entity.
3010 -- This is not allowed for renaming as body if the renamed
3011 -- spec is already frozen (see RM 8.5.4(5) for details).
3013 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
3015 ("renaming-as-body cannot rename entry as subprogram", N
);
3017 ("\since & is already frozen (RM 8.5.4(5))",
3020 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
3027 -- Case where name is an explicit dereference X.all
3029 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
3031 -- Renamed entity is designated by access_to_subprogram expression.
3032 -- Must build body to encapsulate call, as in the entry case.
3034 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
3037 -- Indexed component
3039 elsif Nkind
(Nam
) = N_Indexed_Component
then
3040 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
3043 -- Character literal
3045 elsif Nkind
(Nam
) = N_Character_Literal
then
3046 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
3049 -- Only remaining case is where we have a non-entity name, or a renaming
3050 -- of some other non-overloadable entity.
3052 elsif not Is_Entity_Name
(Nam
)
3053 or else not Is_Overloadable
(Entity
(Nam
))
3055 -- Do not mention the renaming if it comes from an instance
3057 if not Is_Actual
then
3058 Error_Msg_N
("expect valid subprogram name in renaming", N
);
3060 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3066 -- Find the renamed entity that matches the given specification. Disable
3067 -- Ada_83 because there is no requirement of full conformance between
3068 -- renamed entity and new entity, even though the same circuit is used.
3070 -- This is a bit of an odd case, which introduces a really irregular use
3071 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3074 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3075 Ada_Version_Pragma
:= Empty
;
3076 Ada_Version_Explicit
:= Ada_Version
;
3079 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3081 -- The visible operation may be an inherited abstract operation that
3082 -- was overridden in the private part, in which case a call will
3083 -- dispatch to the overriding operation. Use the overriding one in
3084 -- the renaming declaration, to prevent spurious errors below.
3086 if Is_Overloadable
(Old_S
)
3087 and then Is_Abstract_Subprogram
(Old_S
)
3088 and then No
(DTC_Entity
(Old_S
))
3089 and then Present
(Alias
(Old_S
))
3090 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3091 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3093 Old_S
:= Alias
(Old_S
);
3096 -- When the renamed subprogram is overloaded and used as an actual
3097 -- of a generic, its entity is set to the first available homonym.
3098 -- We must first disambiguate the name, then set the proper entity.
3100 if Is_Actual
and then Is_Overloaded
(Nam
) then
3101 Set_Entity
(Nam
, Old_S
);
3105 -- Most common case: subprogram renames subprogram. No body is generated
3106 -- in this case, so we must indicate the declaration is complete as is.
3107 -- and inherit various attributes of the renamed subprogram.
3109 if No
(Rename_Spec
) then
3110 Set_Has_Completion
(New_S
);
3111 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3112 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3113 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3115 -- The subprogram renaming declaration may become Ghost if it renames
3118 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
3120 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3121 -- between a subprogram and its correct renaming.
3123 -- Note: the Any_Id check is a guard that prevents compiler crashes
3124 -- when performing a null exclusion check between a renaming and a
3125 -- renamed subprogram that has been found to be illegal.
3127 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3128 Check_Null_Exclusion
3130 Sub
=> Entity
(Nam
));
3133 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3134 -- overriding. The flag Requires_Overriding is set very selectively
3135 -- and misses some other illegal cases. The additional conditions
3136 -- checked below are sufficient but not necessary ???
3138 -- The rule does not apply to the renaming generated for an actual
3139 -- subprogram in an instance.
3144 -- Guard against previous errors, and omit renamings of predefined
3147 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3150 elsif Requires_Overriding
(Old_S
)
3152 (Is_Abstract_Subprogram
(Old_S
)
3153 and then Present
(Find_Dispatching_Type
(Old_S
))
3155 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3158 ("renamed entity cannot be "
3159 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3163 if Old_S
/= Any_Id
then
3164 if Is_Actual
and then From_Default
(N
) then
3166 -- This is an implicit reference to the default actual
3168 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3171 Generate_Reference
(Old_S
, Nam
);
3174 Check_Internal_Protected_Use
(N
, Old_S
);
3176 -- For a renaming-as-body, require subtype conformance, but if the
3177 -- declaration being completed has not been frozen, then inherit the
3178 -- convention of the renamed subprogram prior to checking conformance
3179 -- (unless the renaming has an explicit convention established; the
3180 -- rule stated in the RM doesn't seem to address this ???).
3182 if Present
(Rename_Spec
) then
3183 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3184 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3186 if not Is_Frozen
(Rename_Spec
) then
3187 if not Has_Convention_Pragma
(Rename_Spec
) then
3188 Set_Convention
(New_S
, Convention
(Old_S
));
3191 if Ekind
(Old_S
) /= E_Operator
then
3192 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3195 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3196 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3199 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3202 Check_Frozen_Renaming
(N
, Rename_Spec
);
3204 -- Check explicitly that renamed entity is not intrinsic, because
3205 -- in a generic the renamed body is not built. In this case,
3206 -- the renaming_as_body is a completion.
3208 if Inside_A_Generic
then
3209 if Is_Frozen
(Rename_Spec
)
3210 and then Is_Intrinsic_Subprogram
(Old_S
)
3213 ("subprogram in renaming_as_body cannot be intrinsic",
3217 Set_Has_Completion
(Rename_Spec
);
3220 elsif Ekind
(Old_S
) /= E_Operator
then
3222 -- If this a defaulted subprogram for a class-wide actual there is
3223 -- no check for mode conformance, given that the signatures don't
3224 -- match (the source mentions T but the actual mentions T'Class).
3228 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3229 Check_Mode_Conformant
(New_S
, Old_S
);
3232 if Is_Actual
and then Error_Posted
(New_S
) then
3233 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3237 if No
(Rename_Spec
) then
3239 -- The parameter profile of the new entity is that of the renamed
3240 -- entity: the subtypes given in the specification are irrelevant.
3242 Inherit_Renamed_Profile
(New_S
, Old_S
);
3244 -- A call to the subprogram is transformed into a call to the
3245 -- renamed entity. This is transitive if the renamed entity is
3246 -- itself a renaming.
3248 if Present
(Alias
(Old_S
)) then
3249 Set_Alias
(New_S
, Alias
(Old_S
));
3251 Set_Alias
(New_S
, Old_S
);
3254 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3255 -- renaming as body, since the entity in this case is not an
3256 -- intrinsic (it calls an intrinsic, but we have a real body for
3257 -- this call, and it is in this body that the required intrinsic
3258 -- processing will take place).
3260 -- Also, if this is a renaming of inequality, the renamed operator
3261 -- is intrinsic, but what matters is the corresponding equality
3262 -- operator, which may be user-defined.
3264 Set_Is_Intrinsic_Subprogram
3266 Is_Intrinsic_Subprogram
(Old_S
)
3268 (Chars
(Old_S
) /= Name_Op_Ne
3269 or else Ekind
(Old_S
) = E_Operator
3270 or else Is_Intrinsic_Subprogram
3271 (Corresponding_Equality
(Old_S
))));
3273 if Ekind
(Alias
(New_S
)) = E_Operator
then
3274 Set_Has_Delayed_Freeze
(New_S
, False);
3277 -- If the renaming corresponds to an association for an abstract
3278 -- formal subprogram, then various attributes must be set to
3279 -- indicate that the renaming is an abstract dispatching operation
3280 -- with a controlling type.
3282 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3284 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3285 -- see it as corresponding to a generic association for a
3286 -- formal abstract subprogram
3288 Set_Is_Abstract_Subprogram
(New_S
);
3291 New_S_Ctrl_Type
: constant Entity_Id
:=
3292 Find_Dispatching_Type
(New_S
);
3293 Old_S_Ctrl_Type
: constant Entity_Id
:=
3294 Find_Dispatching_Type
(Old_S
);
3297 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
3299 ("actual must be dispatching subprogram for type&",
3300 Nam
, New_S_Ctrl_Type
);
3303 Set_Is_Dispatching_Operation
(New_S
);
3304 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3306 -- If the actual in the formal subprogram is itself a
3307 -- formal abstract subprogram association, there's no
3308 -- dispatch table component or position to inherit.
3310 if Present
(DTC_Entity
(Old_S
)) then
3311 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3312 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3322 -- The following is illegal, because F hides whatever other F may
3324 -- function F (...) renames F;
3327 or else (Nkind
(Nam
) /= N_Expanded_Name
3328 and then Chars
(Old_S
) = Chars
(New_S
))
3330 Error_Msg_N
("subprogram cannot rename itself", N
);
3332 -- This is illegal even if we use a selector:
3333 -- function F (...) renames Pkg.F;
3334 -- because F is still hidden.
3336 elsif Nkind
(Nam
) = N_Expanded_Name
3337 and then Entity
(Prefix
(Nam
)) = Current_Scope
3338 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3340 -- This is an error, but we overlook the error and accept the
3341 -- renaming if the special Overriding_Renamings mode is in effect.
3343 if not Overriding_Renamings
then
3345 ("implicit operation& is not visible (RM 8.3 (15))",
3350 Set_Convention
(New_S
, Convention
(Old_S
));
3352 if Is_Abstract_Subprogram
(Old_S
) then
3353 if Present
(Rename_Spec
) then
3355 ("a renaming-as-body cannot rename an abstract subprogram",
3357 Set_Has_Completion
(Rename_Spec
);
3359 Set_Is_Abstract_Subprogram
(New_S
);
3363 Check_Library_Unit_Renaming
(N
, Old_S
);
3365 -- Pathological case: procedure renames entry in the scope of its
3366 -- task. Entry is given by simple name, but body must be built for
3367 -- procedure. Of course if called it will deadlock.
3369 if Ekind
(Old_S
) = E_Entry
then
3370 Set_Has_Completion
(New_S
, False);
3371 Set_Alias
(New_S
, Empty
);
3375 Freeze_Before
(N
, Old_S
);
3376 Freeze_Actual_Profile
;
3377 Set_Has_Delayed_Freeze
(New_S
, False);
3378 Freeze_Before
(N
, New_S
);
3380 -- An abstract subprogram is only allowed as an actual in the case
3381 -- where the formal subprogram is also abstract.
3383 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3384 and then Is_Abstract_Subprogram
(Old_S
)
3385 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3388 ("abstract subprogram not allowed as generic actual", Nam
);
3393 -- A common error is to assume that implicit operators for types are
3394 -- defined in Standard, or in the scope of a subtype. In those cases
3395 -- where the renamed entity is given with an expanded name, it is
3396 -- worth mentioning that operators for the type are not declared in
3397 -- the scope given by the prefix.
3399 if Nkind
(Nam
) = N_Expanded_Name
3400 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3401 and then Scope
(Entity
(Nam
)) = Standard_Standard
3404 T
: constant Entity_Id
:=
3405 Base_Type
(Etype
(First_Formal
(New_S
)));
3407 Error_Msg_Node_2
:= Prefix
(Nam
);
3409 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3414 ("no visible subprogram matches the specification for&",
3418 if Present
(Candidate_Renaming
) then
3425 F1
:= First_Formal
(Candidate_Renaming
);
3426 F2
:= First_Formal
(New_S
);
3427 T1
:= First_Subtype
(Etype
(F1
));
3428 while Present
(F1
) and then Present
(F2
) loop
3433 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3434 if Present
(Next_Formal
(F1
)) then
3436 ("\missing specification for & and other formals with "
3437 & "defaults", Spec
, F1
);
3439 Error_Msg_NE
("\missing specification for &", Spec
, F1
);
3443 if Nkind
(Nam
) = N_Operator_Symbol
3444 and then From_Default
(N
)
3446 Error_Msg_Node_2
:= T1
;
3448 ("default & on & is not directly visible",
3455 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3456 -- controlling access parameters are known non-null for the renamed
3457 -- subprogram. Test also applies to a subprogram instantiation that
3458 -- is dispatching. Test is skipped if some previous error was detected
3459 -- that set Old_S to Any_Id.
3461 if Ada_Version
>= Ada_2005
3462 and then Old_S
/= Any_Id
3463 and then not Is_Dispatching_Operation
(Old_S
)
3464 and then Is_Dispatching_Operation
(New_S
)
3471 Old_F
:= First_Formal
(Old_S
);
3472 New_F
:= First_Formal
(New_S
);
3473 while Present
(Old_F
) loop
3474 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3475 and then Is_Controlling_Formal
(New_F
)
3476 and then not Can_Never_Be_Null
(Old_F
)
3478 Error_Msg_N
("access parameter is controlling,", New_F
);
3480 ("\corresponding parameter of& "
3481 & "must be explicitly null excluding", New_F
, Old_S
);
3484 Next_Formal
(Old_F
);
3485 Next_Formal
(New_F
);
3490 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3491 -- is to warn if an operator is being renamed as a different operator.
3492 -- If the operator is predefined, examine the kind of the entity, not
3493 -- the abbreviated declaration in Standard.
3495 if Comes_From_Source
(N
)
3496 and then Present
(Old_S
)
3497 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3498 or else Ekind
(Old_S
) = E_Operator
)
3499 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3500 and then Chars
(Old_S
) /= Chars
(New_S
)
3503 ("& is being renamed as a different operator??", N
, Old_S
);
3506 -- Check for renaming of obsolescent subprogram
3508 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3510 -- Another warning or some utility: if the new subprogram as the same
3511 -- name as the old one, the old one is not hidden by an outer homograph,
3512 -- the new one is not a public symbol, and the old one is otherwise
3513 -- directly visible, the renaming is superfluous.
3515 if Chars
(Old_S
) = Chars
(New_S
)
3516 and then Comes_From_Source
(N
)
3517 and then Scope
(Old_S
) /= Standard_Standard
3518 and then Warn_On_Redundant_Constructs
3519 and then (Is_Immediately_Visible
(Old_S
)
3520 or else Is_Potentially_Use_Visible
(Old_S
))
3521 and then Is_Overloadable
(Current_Scope
)
3522 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3525 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3528 -- Implementation-defined aspect specifications can appear in a renaming
3529 -- declaration, but not language-defined ones. The call to procedure
3530 -- Analyze_Aspect_Specifications will take care of this error check.
3532 if Has_Aspects
(N
) then
3533 Analyze_Aspect_Specifications
(N
, New_S
);
3536 Ada_Version
:= Save_AV
;
3537 Ada_Version_Pragma
:= Save_AVP
;
3538 Ada_Version_Explicit
:= Save_AV_Exp
;
3540 -- In GNATprove mode, the renamings of actual subprograms are replaced
3541 -- with wrapper functions that make it easier to propagate axioms to the
3542 -- points of call within an instance. Wrappers are generated if formal
3543 -- subprogram is subject to axiomatization.
3545 -- The types in the wrapper profiles are obtained from (instances of)
3546 -- the types of the formal subprogram.
3549 and then GNATprove_Mode
3550 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3551 and then not Inside_A_Generic
3553 if Ekind
(Old_S
) = E_Function
then
3554 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3557 elsif Ekind
(Old_S
) = E_Operator
then
3558 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3563 -- Restore the original Ghost mode once analysis and expansion have
3567 end Analyze_Subprogram_Renaming
;
3569 -------------------------
3570 -- Analyze_Use_Package --
3571 -------------------------
3573 -- Resolve the package names in the use clause, and make all the visible
3574 -- entities defined in the package potentially use-visible. If the package
3575 -- is already in use from a previous use clause, its visible entities are
3576 -- already use-visible. In that case, mark the occurrence as a redundant
3577 -- use. If the package is an open scope, i.e. if the use clause occurs
3578 -- within the package itself, ignore it.
3580 procedure Analyze_Use_Package
(N
: Node_Id
) is
3581 Pack_Name
: Node_Id
;
3584 -- Start of processing for Analyze_Use_Package
3587 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3589 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3591 -- Use clause not allowed in a spec of a predefined package declaration
3592 -- except that packages whose file name starts a-n are OK (these are
3593 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3595 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3596 and then Name_Buffer
(1 .. 3) /= "a-n"
3598 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3600 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3603 -- Chain clause to list of use clauses in current scope
3605 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3606 Chain_Use_Clause
(N
);
3609 -- Loop through package names to identify referenced packages
3611 Pack_Name
:= First
(Names
(N
));
3612 while Present
(Pack_Name
) loop
3613 Analyze
(Pack_Name
);
3615 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3616 and then Nkind
(Pack_Name
) = N_Expanded_Name
3622 Pref
:= Prefix
(Pack_Name
);
3623 while Nkind
(Pref
) = N_Expanded_Name
loop
3624 Pref
:= Prefix
(Pref
);
3627 if Entity
(Pref
) = Standard_Standard
then
3629 ("predefined package Standard cannot appear"
3630 & " in a context clause", Pref
);
3638 -- Loop through package names to mark all entities as potentially
3641 Pack_Name
:= First
(Names
(N
));
3642 while Present
(Pack_Name
) loop
3643 if Is_Entity_Name
(Pack_Name
) then
3644 Pack
:= Entity
(Pack_Name
);
3646 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3647 if Ekind
(Pack
) = E_Generic_Package
then
3648 Error_Msg_N
-- CODEFIX
3649 ("a generic package is not allowed in a use clause",
3652 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3654 Error_Msg_N
-- CODEFIX
3655 ("a generic subprogram is not allowed in a use clause",
3658 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3659 Error_Msg_N
-- CODEFIX
3660 ("a subprogram is not allowed in a use clause",
3664 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3668 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3669 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3672 if Applicable_Use
(Pack_Name
) then
3673 Use_One_Package
(Pack
, N
);
3677 -- Report error because name denotes something other than a package
3680 Error_Msg_N
("& is not a package", Pack_Name
);
3685 end Analyze_Use_Package
;
3687 ----------------------
3688 -- Analyze_Use_Type --
3689 ----------------------
3691 procedure Analyze_Use_Type
(N
: Node_Id
) is
3696 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3698 -- Chain clause to list of use clauses in current scope
3700 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3701 Chain_Use_Clause
(N
);
3704 -- If the Used_Operations list is already initialized, the clause has
3705 -- been analyzed previously, and it is begin reinstalled, for example
3706 -- when the clause appears in a package spec and we are compiling the
3707 -- corresponding package body. In that case, make the entities on the
3708 -- existing list use_visible, and mark the corresponding types In_Use.
3710 if Present
(Used_Operations
(N
)) then
3716 Mark
:= First
(Subtype_Marks
(N
));
3717 while Present
(Mark
) loop
3718 Use_One_Type
(Mark
, Installed
=> True);
3722 Elmt
:= First_Elmt
(Used_Operations
(N
));
3723 while Present
(Elmt
) loop
3724 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3732 -- Otherwise, create new list and attach to it the operations that
3733 -- are made use-visible by the clause.
3735 Set_Used_Operations
(N
, New_Elmt_List
);
3736 Id
:= First
(Subtype_Marks
(N
));
3737 while Present
(Id
) loop
3741 if E
/= Any_Type
then
3744 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3745 if Nkind
(Id
) = N_Identifier
then
3746 Error_Msg_N
("type is not directly visible", Id
);
3748 elsif Is_Child_Unit
(Scope
(E
))
3749 and then Scope
(E
) /= System_Aux_Id
3751 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3756 -- If the use_type_clause appears in a compilation unit context,
3757 -- check whether it comes from a unit that may appear in a
3758 -- limited_with_clause, for a better error message.
3760 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3761 and then Nkind
(Id
) /= N_Identifier
3767 function Mentioned
(Nam
: Node_Id
) return Boolean;
3768 -- Check whether the prefix of expanded name for the type
3769 -- appears in the prefix of some limited_with_clause.
3775 function Mentioned
(Nam
: Node_Id
) return Boolean is
3777 return Nkind
(Name
(Item
)) = N_Selected_Component
3778 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3782 Pref
:= Prefix
(Id
);
3783 Item
:= First
(Context_Items
(Parent
(N
)));
3784 while Present
(Item
) and then Item
/= N
loop
3785 if Nkind
(Item
) = N_With_Clause
3786 and then Limited_Present
(Item
)
3787 and then Mentioned
(Pref
)
3790 (Get_Msg_Id
, "premature usage of incomplete type");
3801 end Analyze_Use_Type
;
3803 --------------------
3804 -- Applicable_Use --
3805 --------------------
3807 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3808 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3811 if In_Open_Scopes
(Pack
) then
3812 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3813 Error_Msg_NE
-- CODEFIX
3814 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3819 elsif In_Use
(Pack
) then
3820 Note_Redundant_Use
(Pack_Name
);
3823 elsif Present
(Renamed_Object
(Pack
))
3824 and then In_Use
(Renamed_Object
(Pack
))
3826 Note_Redundant_Use
(Pack_Name
);
3834 ------------------------
3835 -- Attribute_Renaming --
3836 ------------------------
3838 procedure Attribute_Renaming
(N
: Node_Id
) is
3839 Loc
: constant Source_Ptr
:= Sloc
(N
);
3840 Nam
: constant Node_Id
:= Name
(N
);
3841 Spec
: constant Node_Id
:= Specification
(N
);
3842 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3843 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3845 Form_Num
: Nat
:= 0;
3846 Expr_List
: List_Id
:= No_List
;
3848 Attr_Node
: Node_Id
;
3849 Body_Node
: Node_Id
;
3850 Param_Spec
: Node_Id
;
3853 Generate_Definition
(New_S
);
3855 -- This procedure is called in the context of subprogram renaming, and
3856 -- thus the attribute must be one that is a subprogram. All of those
3857 -- have at least one formal parameter, with the exceptions of the GNAT
3858 -- attribute 'Img, which GNAT treats as renameable.
3860 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3861 if Aname
/= Name_Img
then
3863 ("subprogram renaming an attribute must have formals", N
);
3868 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3869 while Present
(Param_Spec
) loop
3870 Form_Num
:= Form_Num
+ 1;
3872 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3873 Find_Type
(Parameter_Type
(Param_Spec
));
3875 -- The profile of the new entity denotes the base type (s) of
3876 -- the types given in the specification. For access parameters
3877 -- there are no subtypes involved.
3879 Rewrite
(Parameter_Type
(Param_Spec
),
3881 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3884 if No
(Expr_List
) then
3885 Expr_List
:= New_List
;
3888 Append_To
(Expr_List
,
3889 Make_Identifier
(Loc
,
3890 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3892 -- The expressions in the attribute reference are not freeze
3893 -- points. Neither is the attribute as a whole, see below.
3895 Set_Must_Not_Freeze
(Last
(Expr_List
));
3900 -- Immediate error if too many formals. Other mismatches in number or
3901 -- types of parameters are detected when we analyze the body of the
3902 -- subprogram that we construct.
3904 if Form_Num
> 2 then
3905 Error_Msg_N
("too many formals for attribute", N
);
3907 -- Error if the attribute reference has expressions that look like
3908 -- formal parameters.
3910 elsif Present
(Expressions
(Nam
)) then
3911 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3914 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3915 Name_Pos
, Name_Round
, Name_Scaling
,
3918 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3919 and then Present
(Corresponding_Formal_Spec
(N
))
3922 ("generic actual cannot be attribute involving universal type",
3926 ("attribute involving a universal type cannot be renamed",
3931 -- Rewrite attribute node to have a list of expressions corresponding to
3932 -- the subprogram formals. A renaming declaration is not a freeze point,
3933 -- and the analysis of the attribute reference should not freeze the
3934 -- type of the prefix. We use the original node in the renaming so that
3935 -- its source location is preserved, and checks on stream attributes are
3936 -- properly applied.
3938 Attr_Node
:= Relocate_Node
(Nam
);
3939 Set_Expressions
(Attr_Node
, Expr_List
);
3941 Set_Must_Not_Freeze
(Attr_Node
);
3942 Set_Must_Not_Freeze
(Prefix
(Nam
));
3944 -- Case of renaming a function
3946 if Nkind
(Spec
) = N_Function_Specification
then
3947 if Is_Procedure_Attribute_Name
(Aname
) then
3948 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3952 Find_Type
(Result_Definition
(Spec
));
3953 Rewrite
(Result_Definition
(Spec
),
3955 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3958 Make_Subprogram_Body
(Loc
,
3959 Specification
=> Spec
,
3960 Declarations
=> New_List
,
3961 Handled_Statement_Sequence
=>
3962 Make_Handled_Sequence_Of_Statements
(Loc
,
3963 Statements
=> New_List
(
3964 Make_Simple_Return_Statement
(Loc
,
3965 Expression
=> Attr_Node
))));
3967 -- Case of renaming a procedure
3970 if not Is_Procedure_Attribute_Name
(Aname
) then
3971 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3976 Make_Subprogram_Body
(Loc
,
3977 Specification
=> Spec
,
3978 Declarations
=> New_List
,
3979 Handled_Statement_Sequence
=>
3980 Make_Handled_Sequence_Of_Statements
(Loc
,
3981 Statements
=> New_List
(Attr_Node
)));
3984 -- In case of tagged types we add the body of the generated function to
3985 -- the freezing actions of the type (because in the general case such
3986 -- type is still not frozen). We exclude from this processing generic
3987 -- formal subprograms found in instantiations.
3989 -- We must exclude VM targets and restricted run-time libraries because
3990 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3991 -- available in those platforms. Note that we cannot use the function
3992 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3993 -- the ZFP run-time library is not defined as a profile, and we do not
3994 -- want to deal with AST_Handler in ZFP mode.
3996 if VM_Target
= No_VM
3997 and then not Configurable_Run_Time_Mode
3998 and then not Present
(Corresponding_Formal_Spec
(N
))
3999 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
4002 P
: constant Node_Id
:= Prefix
(Nam
);
4005 -- The prefix of 'Img is an object that is evaluated for each call
4006 -- of the function that renames it.
4008 if Aname
= Name_Img
then
4009 Preanalyze_And_Resolve
(P
);
4011 -- For all other attribute renamings, the prefix is a subtype
4017 -- If the target type is not yet frozen, add the body to the
4018 -- actions to be elaborated at freeze time.
4020 if Is_Tagged_Type
(Etype
(P
))
4021 and then In_Open_Scopes
(Scope
(Etype
(P
)))
4023 Ensure_Freeze_Node
(Etype
(P
));
4024 Append_Freeze_Action
(Etype
(P
), Body_Node
);
4026 Rewrite
(N
, Body_Node
);
4028 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4032 -- Generic formal subprograms or AST_Handler renaming
4035 Rewrite
(N
, Body_Node
);
4037 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4040 if Is_Compilation_Unit
(New_S
) then
4042 ("a library unit can only rename another library unit", N
);
4045 -- We suppress elaboration warnings for the resulting entity, since
4046 -- clearly they are not needed, and more particularly, in the case
4047 -- of a generic formal subprogram, the resulting entity can appear
4048 -- after the instantiation itself, and thus look like a bogus case
4049 -- of access before elaboration.
4051 Set_Suppress_Elaboration_Warnings
(New_S
);
4053 end Attribute_Renaming
;
4055 ----------------------
4056 -- Chain_Use_Clause --
4057 ----------------------
4059 procedure Chain_Use_Clause
(N
: Node_Id
) is
4061 Level
: Int
:= Scope_Stack
.Last
;
4064 if not Is_Compilation_Unit
(Current_Scope
)
4065 or else not Is_Child_Unit
(Current_Scope
)
4067 null; -- Common case
4069 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
4070 null; -- Common case for compilation unit
4073 -- If declaration appears in some other scope, it must be in some
4074 -- parent unit when compiling a child.
4076 Pack
:= Defining_Entity
(Parent
(N
));
4077 if not In_Open_Scopes
(Pack
) then
4078 null; -- default as well
4080 -- If the use clause appears in an ancestor and we are in the
4081 -- private part of the immediate parent, the use clauses are
4082 -- already installed.
4084 elsif Pack
/= Scope
(Current_Scope
)
4085 and then In_Private_Part
(Scope
(Current_Scope
))
4090 -- Find entry for parent unit in scope stack
4092 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4098 Set_Next_Use_Clause
(N
,
4099 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4100 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4101 end Chain_Use_Clause
;
4103 ---------------------------
4104 -- Check_Frozen_Renaming --
4105 ---------------------------
4107 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4112 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4115 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4117 if Is_Entity_Name
(Name
(N
)) then
4118 Old_S
:= Entity
(Name
(N
));
4120 if not Is_Frozen
(Old_S
)
4121 and then Operating_Mode
/= Check_Semantics
4123 Append_Freeze_Action
(Old_S
, B_Node
);
4125 Insert_After
(N
, B_Node
);
4129 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4131 ("subprogram used in renaming_as_body cannot be intrinsic",
4136 Insert_After
(N
, B_Node
);
4140 end Check_Frozen_Renaming
;
4142 -------------------------------
4143 -- Set_Entity_Or_Discriminal --
4144 -------------------------------
4146 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4150 -- If the entity is not a discriminant, or else expansion is disabled,
4151 -- simply set the entity.
4153 if not In_Spec_Expression
4154 or else Ekind
(E
) /= E_Discriminant
4155 or else Inside_A_Generic
4157 Set_Entity_With_Checks
(N
, E
);
4159 -- The replacement of a discriminant by the corresponding discriminal
4160 -- is not done for a task discriminant that appears in a default
4161 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4162 -- for details on their handling.
4164 elsif Is_Concurrent_Type
(Scope
(E
)) then
4167 and then not Nkind_In
(P
, N_Parameter_Specification
,
4168 N_Component_Declaration
)
4174 and then Nkind
(P
) = N_Parameter_Specification
4179 Set_Entity
(N
, Discriminal
(E
));
4182 -- Otherwise, this is a discriminant in a context in which
4183 -- it is a reference to the corresponding parameter of the
4184 -- init proc for the enclosing type.
4187 Set_Entity
(N
, Discriminal
(E
));
4189 end Set_Entity_Or_Discriminal
;
4191 -----------------------------------
4192 -- Check_In_Previous_With_Clause --
4193 -----------------------------------
4195 procedure Check_In_Previous_With_Clause
4199 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4204 Item
:= First
(Context_Items
(Parent
(N
)));
4205 while Present
(Item
) and then Item
/= N
loop
4206 if Nkind
(Item
) = N_With_Clause
4208 -- Protect the frontend against previous critical errors
4210 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4211 and then Entity
(Name
(Item
)) = Pack
4215 -- Find root library unit in with_clause
4217 while Nkind
(Par
) = N_Expanded_Name
loop
4218 Par
:= Prefix
(Par
);
4221 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4222 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4231 -- On exit, package is not mentioned in a previous with_clause.
4232 -- Check if its prefix is.
4234 if Nkind
(Nam
) = N_Expanded_Name
then
4235 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4237 elsif Pack
/= Any_Id
then
4238 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4240 end Check_In_Previous_With_Clause
;
4242 ---------------------------------
4243 -- Check_Library_Unit_Renaming --
4244 ---------------------------------
4246 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4250 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4253 -- Check for library unit. Note that we used to check for the scope
4254 -- being Standard here, but that was wrong for Standard itself.
4256 elsif not Is_Compilation_Unit
(Old_E
)
4257 and then not Is_Child_Unit
(Old_E
)
4259 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4261 -- Entities defined in Standard (operators and boolean literals) cannot
4262 -- be renamed as library units.
4264 elsif Scope
(Old_E
) = Standard_Standard
4265 and then Sloc
(Old_E
) = Standard_Location
4267 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4269 elsif Present
(Parent_Spec
(N
))
4270 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4271 and then not Is_Child_Unit
(Old_E
)
4274 ("renamed unit must be a child unit of generic parent", Name
(N
));
4276 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4277 and then Nkind
(Name
(N
)) = N_Expanded_Name
4278 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4279 and then Is_Generic_Unit
(Old_E
)
4282 ("renamed generic unit must be a library unit", Name
(N
));
4284 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4286 -- Inherit categorization flags
4288 New_E
:= Defining_Entity
(N
);
4289 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4290 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4291 Set_Is_Remote_Call_Interface
(New_E
,
4292 Is_Remote_Call_Interface
(Old_E
));
4293 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4294 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4296 end Check_Library_Unit_Renaming
;
4298 ------------------------
4299 -- Enclosing_Instance --
4300 ------------------------
4302 function Enclosing_Instance
return Entity_Id
is
4306 if not Is_Generic_Instance
(Current_Scope
) then
4310 S
:= Scope
(Current_Scope
);
4311 while S
/= Standard_Standard
loop
4312 if Is_Generic_Instance
(S
) then
4320 end Enclosing_Instance
;
4326 procedure End_Scope
is
4332 Id
:= First_Entity
(Current_Scope
);
4333 while Present
(Id
) loop
4334 -- An entity in the current scope is not necessarily the first one
4335 -- on its homonym chain. Find its predecessor if any,
4336 -- If it is an internal entity, it will not be in the visibility
4337 -- chain altogether, and there is nothing to unchain.
4339 if Id
/= Current_Entity
(Id
) then
4340 Prev
:= Current_Entity
(Id
);
4341 while Present
(Prev
)
4342 and then Present
(Homonym
(Prev
))
4343 and then Homonym
(Prev
) /= Id
4345 Prev
:= Homonym
(Prev
);
4348 -- Skip to end of loop if Id is not in the visibility chain
4350 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4358 Set_Is_Immediately_Visible
(Id
, False);
4360 Outer
:= Homonym
(Id
);
4361 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4362 Outer
:= Homonym
(Outer
);
4365 -- Reset homonym link of other entities, but do not modify link
4366 -- between entities in current scope, so that the back-end can have
4367 -- a proper count of local overloadings.
4370 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4372 elsif Scope
(Prev
) /= Scope
(Id
) then
4373 Set_Homonym
(Prev
, Outer
);
4380 -- If the scope generated freeze actions, place them before the
4381 -- current declaration and analyze them. Type declarations and
4382 -- the bodies of initialization procedures can generate such nodes.
4383 -- We follow the parent chain until we reach a list node, which is
4384 -- the enclosing list of declarations. If the list appears within
4385 -- a protected definition, move freeze nodes outside the protected
4389 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4393 L
: constant List_Id
:= Scope_Stack
.Table
4394 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4397 if Is_Itype
(Current_Scope
) then
4398 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4400 Decl
:= Parent
(Current_Scope
);
4405 while not (Is_List_Member
(Decl
))
4406 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4409 Decl
:= Parent
(Decl
);
4412 Insert_List_Before_And_Analyze
(Decl
, L
);
4420 ---------------------
4421 -- End_Use_Clauses --
4422 ---------------------
4424 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4428 -- Remove Use_Type clauses first, because they affect the
4429 -- visibility of operators in subsequent used packages.
4432 while Present
(U
) loop
4433 if Nkind
(U
) = N_Use_Type_Clause
then
4437 Next_Use_Clause
(U
);
4441 while Present
(U
) loop
4442 if Nkind
(U
) = N_Use_Package_Clause
then
4443 End_Use_Package
(U
);
4446 Next_Use_Clause
(U
);
4448 end End_Use_Clauses
;
4450 ---------------------
4451 -- End_Use_Package --
4452 ---------------------
4454 procedure End_Use_Package
(N
: Node_Id
) is
4455 Pack_Name
: Node_Id
;
4460 function Is_Primitive_Operator_In_Use
4462 F
: Entity_Id
) return Boolean;
4463 -- Check whether Op is a primitive operator of a use-visible type
4465 ----------------------------------
4466 -- Is_Primitive_Operator_In_Use --
4467 ----------------------------------
4469 function Is_Primitive_Operator_In_Use
4471 F
: Entity_Id
) return Boolean
4473 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4475 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4476 end Is_Primitive_Operator_In_Use
;
4478 -- Start of processing for End_Use_Package
4481 Pack_Name
:= First
(Names
(N
));
4482 while Present
(Pack_Name
) loop
4484 -- Test that Pack_Name actually denotes a package before processing
4486 if Is_Entity_Name
(Pack_Name
)
4487 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4489 Pack
:= Entity
(Pack_Name
);
4491 if In_Open_Scopes
(Pack
) then
4494 elsif not Redundant_Use
(Pack_Name
) then
4495 Set_In_Use
(Pack
, False);
4496 Set_Current_Use_Clause
(Pack
, Empty
);
4498 Id
:= First_Entity
(Pack
);
4499 while Present
(Id
) loop
4501 -- Preserve use-visibility of operators that are primitive
4502 -- operators of a type that is use-visible through an active
4505 if Nkind
(Id
) = N_Defining_Operator_Symbol
4507 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4509 (Present
(Next_Formal
(First_Formal
(Id
)))
4511 Is_Primitive_Operator_In_Use
4512 (Id
, Next_Formal
(First_Formal
(Id
)))))
4516 Set_Is_Potentially_Use_Visible
(Id
, False);
4519 if Is_Private_Type
(Id
)
4520 and then Present
(Full_View
(Id
))
4522 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4528 if Present
(Renamed_Object
(Pack
)) then
4529 Set_In_Use
(Renamed_Object
(Pack
), False);
4530 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4533 if Chars
(Pack
) = Name_System
4534 and then Scope
(Pack
) = Standard_Standard
4535 and then Present_System_Aux
4537 Id
:= First_Entity
(System_Aux_Id
);
4538 while Present
(Id
) loop
4539 Set_Is_Potentially_Use_Visible
(Id
, False);
4541 if Is_Private_Type
(Id
)
4542 and then Present
(Full_View
(Id
))
4544 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4550 Set_In_Use
(System_Aux_Id
, False);
4554 Set_Redundant_Use
(Pack_Name
, False);
4561 if Present
(Hidden_By_Use_Clause
(N
)) then
4562 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4563 while Present
(Elmt
) loop
4565 E
: constant Entity_Id
:= Node
(Elmt
);
4568 -- Reset either Use_Visibility or Direct_Visibility, depending
4569 -- on how the entity was hidden by the use clause.
4571 if In_Use
(Scope
(E
))
4572 and then Used_As_Generic_Actual
(Scope
(E
))
4574 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4576 Set_Is_Immediately_Visible
(Node
(Elmt
));
4583 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4585 end End_Use_Package
;
4591 procedure End_Use_Type
(N
: Node_Id
) is
4596 -- Start of processing for End_Use_Type
4599 Id
:= First
(Subtype_Marks
(N
));
4600 while Present
(Id
) loop
4602 -- A call to Rtsfind may occur while analyzing a use_type clause,
4603 -- in which case the type marks are not resolved yet, and there is
4604 -- nothing to remove.
4606 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4612 if T
= Any_Type
or else From_Limited_With
(T
) then
4615 -- Note that the use_type clause may mention a subtype of the type
4616 -- whose primitive operations have been made visible. Here as
4617 -- elsewhere, it is the base type that matters for visibility.
4619 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4622 elsif not Redundant_Use
(Id
) then
4623 Set_In_Use
(T
, False);
4624 Set_In_Use
(Base_Type
(T
), False);
4625 Set_Current_Use_Clause
(T
, Empty
);
4626 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4633 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4637 Elmt
:= First_Elmt
(Used_Operations
(N
));
4638 while Present
(Elmt
) loop
4639 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4645 ----------------------
4646 -- Find_Direct_Name --
4647 ----------------------
4649 procedure Find_Direct_Name
(N
: Node_Id
) is
4654 Inst
: Entity_Id
:= Empty
;
4655 -- Enclosing instance, if any
4657 Homonyms
: Entity_Id
;
4658 -- Saves start of homonym chain
4660 Nvis_Entity
: Boolean;
4661 -- Set True to indicate that there is at least one entity on the homonym
4662 -- chain which, while not visible, is visible enough from the user point
4663 -- of view to warrant an error message of "not visible" rather than
4666 Nvis_Is_Private_Subprg
: Boolean := False;
4667 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4668 -- effect concerning library subprograms has been detected. Used to
4669 -- generate the precise error message.
4671 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4672 -- Returns true if the entity is an actual for a package that is itself
4673 -- an actual for a formal package of the current instance. Such an
4674 -- entity requires special handling because it may be use-visible but
4675 -- hides directly visible entities defined outside the instance, because
4676 -- the corresponding formal did so in the generic.
4678 function Is_Actual_Parameter
return Boolean;
4679 -- This function checks if the node N is an identifier that is an actual
4680 -- parameter of a procedure call. If so it returns True, otherwise it
4681 -- return False. The reason for this check is that at this stage we do
4682 -- not know what procedure is being called if the procedure might be
4683 -- overloaded, so it is premature to go setting referenced flags or
4684 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4685 -- for that processing
4687 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4688 -- This function determines whether a reference to the entity E, which
4689 -- is not visible, can reasonably be considered to be known to the
4690 -- writer of the reference. This is a heuristic test, used only for
4691 -- the purposes of figuring out whether we prefer to complain that an
4692 -- entity is undefined or invisible (and identify the declaration of
4693 -- the invisible entity in the latter case). The point here is that we
4694 -- don't want to complain that something is invisible and then point to
4695 -- something entirely mysterious to the writer.
4697 procedure Nvis_Messages
;
4698 -- Called if there are no visible entries for N, but there is at least
4699 -- one non-directly visible, or hidden declaration. This procedure
4700 -- outputs an appropriate set of error messages.
4702 procedure Undefined
(Nvis
: Boolean);
4703 -- This function is called if the current node has no corresponding
4704 -- visible entity or entities. The value set in Msg indicates whether
4705 -- an error message was generated (multiple error messages for the
4706 -- same variable are generally suppressed, see body for details).
4707 -- Msg is True if an error message was generated, False if not. This
4708 -- value is used by the caller to determine whether or not to output
4709 -- additional messages where appropriate. The parameter is set False
4710 -- to get the message "X is undefined", and True to get the message
4711 -- "X is not visible".
4713 -------------------------
4714 -- From_Actual_Package --
4715 -------------------------
4717 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4718 Scop
: constant Entity_Id
:= Scope
(E
);
4719 -- Declared scope of candidate entity
4723 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4724 -- Recursive function that does the work and examines actuals of
4725 -- actual packages of current instance.
4727 ------------------------
4728 -- Declared_In_Actual --
4729 ------------------------
4731 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4735 if No
(Associated_Formal_Package
(Pack
)) then
4739 Act
:= First_Entity
(Pack
);
4740 while Present
(Act
) loop
4741 if Renamed_Object
(Pack
) = Scop
then
4744 -- Check for end of list of actuals.
4746 elsif Ekind
(Act
) = E_Package
4747 and then Renamed_Object
(Act
) = Pack
4751 elsif Ekind
(Act
) = E_Package
4752 and then Declared_In_Actual
(Act
)
4762 end Declared_In_Actual
;
4764 -- Start of processing for From_Actual_Package
4767 if not In_Instance
then
4771 Inst
:= Current_Scope
;
4772 while Present
(Inst
)
4773 and then Ekind
(Inst
) /= E_Package
4774 and then not Is_Generic_Instance
(Inst
)
4776 Inst
:= Scope
(Inst
);
4783 Act
:= First_Entity
(Inst
);
4784 while Present
(Act
) loop
4785 if Ekind
(Act
) = E_Package
4786 and then Declared_In_Actual
(Act
)
4796 end From_Actual_Package
;
4798 -------------------------
4799 -- Is_Actual_Parameter --
4800 -------------------------
4802 function Is_Actual_Parameter
return Boolean is
4805 Nkind
(N
) = N_Identifier
4807 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4809 (Nkind
(Parent
(N
)) = N_Parameter_Association
4810 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4811 and then Nkind
(Parent
(Parent
(N
))) =
4812 N_Procedure_Call_Statement
));
4813 end Is_Actual_Parameter
;
4815 -------------------------
4816 -- Known_But_Invisible --
4817 -------------------------
4819 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4820 Fname
: File_Name_Type
;
4823 -- Entities in Standard are always considered to be known
4825 if Sloc
(E
) <= Standard_Location
then
4828 -- An entity that does not come from source is always considered
4829 -- to be unknown, since it is an artifact of code expansion.
4831 elsif not Comes_From_Source
(E
) then
4834 -- In gnat internal mode, we consider all entities known. The
4835 -- historical reason behind this discrepancy is not known??? But the
4836 -- only effect is to modify the error message given, so it is not
4837 -- critical. Since it only affects the exact wording of error
4838 -- messages in illegal programs, we do not mention this as an
4839 -- effect of -gnatg, since it is not a language modification.
4841 elsif GNAT_Mode
then
4845 -- Here we have an entity that is not from package Standard, and
4846 -- which comes from Source. See if it comes from an internal file.
4848 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4850 -- Case of from internal file
4852 if Is_Internal_File_Name
(Fname
) then
4854 -- Private part entities in internal files are never considered
4855 -- to be known to the writer of normal application code.
4857 if Is_Hidden
(E
) then
4861 -- Entities from System packages other than System and
4862 -- System.Storage_Elements are not considered to be known.
4863 -- System.Auxxxx files are also considered known to the user.
4865 -- Should refine this at some point to generally distinguish
4866 -- between known and unknown internal files ???
4868 Get_Name_String
(Fname
);
4873 Name_Buffer
(1 .. 2) /= "s-"
4875 Name_Buffer
(3 .. 8) = "stoele"
4877 Name_Buffer
(3 .. 5) = "aux";
4879 -- If not an internal file, then entity is definitely known,
4880 -- even if it is in a private part (the message generated will
4881 -- note that it is in a private part)
4886 end Known_But_Invisible
;
4892 procedure Nvis_Messages
is
4893 Comp_Unit
: Node_Id
;
4895 Found
: Boolean := False;
4896 Hidden
: Boolean := False;
4900 -- Ada 2005 (AI-262): Generate a precise error concerning the
4901 -- Beaujolais effect that was previously detected
4903 if Nvis_Is_Private_Subprg
then
4905 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4906 and then Ekind
(E2
) = E_Function
4907 and then Scope
(E2
) = Standard_Standard
4908 and then Has_Private_With
(E2
));
4910 -- Find the sloc corresponding to the private with'ed unit
4912 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4913 Error_Msg_Sloc
:= No_Location
;
4915 Item
:= First
(Context_Items
(Comp_Unit
));
4916 while Present
(Item
) loop
4917 if Nkind
(Item
) = N_With_Clause
4918 and then Private_Present
(Item
)
4919 and then Entity
(Name
(Item
)) = E2
4921 Error_Msg_Sloc
:= Sloc
(Item
);
4928 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4930 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4934 Undefined
(Nvis
=> True);
4938 -- First loop does hidden declarations
4941 while Present
(Ent
) loop
4942 if Is_Potentially_Use_Visible
(Ent
) then
4944 Error_Msg_N
-- CODEFIX
4945 ("multiple use clauses cause hiding!", N
);
4949 Error_Msg_Sloc
:= Sloc
(Ent
);
4950 Error_Msg_N
-- CODEFIX
4951 ("hidden declaration#!", N
);
4954 Ent
:= Homonym
(Ent
);
4957 -- If we found hidden declarations, then that's enough, don't
4958 -- bother looking for non-visible declarations as well.
4964 -- Second loop does non-directly visible declarations
4967 while Present
(Ent
) loop
4968 if not Is_Potentially_Use_Visible
(Ent
) then
4970 -- Do not bother the user with unknown entities
4972 if not Known_But_Invisible
(Ent
) then
4976 Error_Msg_Sloc
:= Sloc
(Ent
);
4978 -- Output message noting that there is a non-visible
4979 -- declaration, distinguishing the private part case.
4981 if Is_Hidden
(Ent
) then
4982 Error_Msg_N
("non-visible (private) declaration#!", N
);
4984 -- If the entity is declared in a generic package, it
4985 -- cannot be visible, so there is no point in adding it
4986 -- to the list of candidates if another homograph from a
4987 -- non-generic package has been seen.
4989 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4995 Error_Msg_N
-- CODEFIX
4996 ("non-visible declaration#!", N
);
4998 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
5002 if Is_Compilation_Unit
(Ent
)
5004 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
5006 Error_Msg_Qual_Level
:= 99;
5007 Error_Msg_NE
-- CODEFIX
5008 ("\\missing `WITH &;`", N
, Ent
);
5009 Error_Msg_Qual_Level
:= 0;
5012 if Ekind
(Ent
) = E_Discriminant
5013 and then Present
(Corresponding_Discriminant
(Ent
))
5014 and then Scope
(Corresponding_Discriminant
(Ent
)) =
5018 ("inherited discriminant not allowed here" &
5019 " (RM 3.8 (12), 3.8.1 (6))!", N
);
5023 -- Set entity and its containing package as referenced. We
5024 -- can't be sure of this, but this seems a better choice
5025 -- to avoid unused entity messages.
5027 if Comes_From_Source
(Ent
) then
5028 Set_Referenced
(Ent
);
5029 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
5034 Ent
:= Homonym
(Ent
);
5043 procedure Undefined
(Nvis
: Boolean) is
5044 Emsg
: Error_Msg_Id
;
5047 -- We should never find an undefined internal name. If we do, then
5048 -- see if we have previous errors. If so, ignore on the grounds that
5049 -- it is probably a cascaded message (e.g. a block label from a badly
5050 -- formed block). If no previous errors, then we have a real internal
5051 -- error of some kind so raise an exception.
5053 if Is_Internal_Name
(Chars
(N
)) then
5054 if Total_Errors_Detected
/= 0 then
5057 raise Program_Error
;
5061 -- A very specialized error check, if the undefined variable is
5062 -- a case tag, and the case type is an enumeration type, check
5063 -- for a possible misspelling, and if so, modify the identifier
5065 -- Named aggregate should also be handled similarly ???
5067 if Nkind
(N
) = N_Identifier
5068 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5071 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5072 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5077 if Is_Enumeration_Type
(Case_Typ
)
5078 and then not Is_Standard_Character_Type
(Case_Typ
)
5080 Lit
:= First_Literal
(Case_Typ
);
5081 Get_Name_String
(Chars
(Lit
));
5083 if Chars
(Lit
) /= Chars
(N
)
5084 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5086 Error_Msg_Node_2
:= Lit
;
5087 Error_Msg_N
-- CODEFIX
5088 ("& is undefined, assume misspelling of &", N
);
5089 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5093 Lit
:= Next_Literal
(Lit
);
5098 -- Normal processing
5100 Set_Entity
(N
, Any_Id
);
5101 Set_Etype
(N
, Any_Type
);
5103 -- We use the table Urefs to keep track of entities for which we
5104 -- have issued errors for undefined references. Multiple errors
5105 -- for a single name are normally suppressed, however we modify
5106 -- the error message to alert the programmer to this effect.
5108 for J
in Urefs
.First
.. Urefs
.Last
loop
5109 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5110 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5111 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5113 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5115 if Urefs
.Table
(J
).Nvis
then
5116 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5117 "& is not visible (more references follow)");
5119 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5120 "& is undefined (more references follow)");
5123 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5126 -- Although we will set Msg False, and thus suppress the
5127 -- message, we also set Error_Posted True, to avoid any
5128 -- cascaded messages resulting from the undefined reference.
5131 Set_Error_Posted
(N
, True);
5136 -- If entry not found, this is first undefined occurrence
5139 Error_Msg_N
("& is not visible!", N
);
5143 Error_Msg_N
("& is undefined!", N
);
5146 -- A very bizarre special check, if the undefined identifier
5147 -- is put or put_line, then add a special error message (since
5148 -- this is a very common error for beginners to make).
5150 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5151 Error_Msg_N
-- CODEFIX
5152 ("\\possible missing `WITH Ada.Text_'I'O; " &
5153 "USE Ada.Text_'I'O`!", N
);
5155 -- Another special check if N is the prefix of a selected
5156 -- component which is a known unit, add message complaining
5157 -- about missing with for this unit.
5159 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5160 and then N
= Prefix
(Parent
(N
))
5161 and then Is_Known_Unit
(Parent
(N
))
5163 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5164 Error_Msg_N
-- CODEFIX
5165 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5168 -- Now check for possible misspellings
5172 Ematch
: Entity_Id
:= Empty
;
5174 Last_Name_Id
: constant Name_Id
:=
5175 Name_Id
(Nat
(First_Name_Id
) +
5176 Name_Entries_Count
- 1);
5179 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5180 E
:= Get_Name_Entity_Id
(Nam
);
5183 and then (Is_Immediately_Visible
(E
)
5185 Is_Potentially_Use_Visible
(E
))
5187 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5194 if Present
(Ematch
) then
5195 Error_Msg_NE
-- CODEFIX
5196 ("\possible misspelling of&", N
, Ematch
);
5201 -- Make entry in undefined references table unless the full errors
5202 -- switch is set, in which case by refraining from generating the
5203 -- table entry, we guarantee that we get an error message for every
5204 -- undefined reference.
5206 if not All_Errors_Mode
then
5217 -- Start of processing for Find_Direct_Name
5220 -- If the entity pointer is already set, this is an internal node, or
5221 -- a node that is analyzed more than once, after a tree modification.
5222 -- In such a case there is no resolution to perform, just set the type.
5224 if Present
(Entity
(N
)) then
5225 if Is_Type
(Entity
(N
)) then
5226 Set_Etype
(N
, Entity
(N
));
5230 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5233 -- One special case here. If the Etype field is already set,
5234 -- and references the packed array type corresponding to the
5235 -- etype of the referenced entity, then leave it alone. This
5236 -- happens for trees generated from Exp_Pakd, where expressions
5237 -- can be deliberately "mis-typed" to the packed array type.
5239 if Is_Array_Type
(Entyp
)
5240 and then Is_Packed
(Entyp
)
5241 and then Present
(Etype
(N
))
5242 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5246 -- If not that special case, then just reset the Etype
5249 Set_Etype
(N
, Etype
(Entity
(N
)));
5257 -- Here if Entity pointer was not set, we need full visibility analysis
5258 -- First we generate debugging output if the debug E flag is set.
5260 if Debug_Flag_E
then
5261 Write_Str
("Looking for ");
5262 Write_Name
(Chars
(N
));
5266 Homonyms
:= Current_Entity
(N
);
5267 Nvis_Entity
:= False;
5270 while Present
(E
) loop
5272 -- If entity is immediately visible or potentially use visible, then
5273 -- process the entity and we are done.
5275 if Is_Immediately_Visible
(E
) then
5276 goto Immediately_Visible_Entity
;
5278 elsif Is_Potentially_Use_Visible
(E
) then
5279 goto Potentially_Use_Visible_Entity
;
5281 -- Note if a known but invisible entity encountered
5283 elsif Known_But_Invisible
(E
) then
5284 Nvis_Entity
:= True;
5287 -- Move to next entity in chain and continue search
5292 -- If no entries on homonym chain that were potentially visible,
5293 -- and no entities reasonably considered as non-visible, then
5294 -- we have a plain undefined reference, with no additional
5295 -- explanation required.
5297 if not Nvis_Entity
then
5298 Undefined
(Nvis
=> False);
5300 -- Otherwise there is at least one entry on the homonym chain that
5301 -- is reasonably considered as being known and non-visible.
5309 -- Processing for a potentially use visible entry found. We must search
5310 -- the rest of the homonym chain for two reasons. First, if there is a
5311 -- directly visible entry, then none of the potentially use-visible
5312 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5313 -- for the case of multiple potentially use-visible entries hiding one
5314 -- another and as a result being non-directly visible (RM 8.4(11)).
5316 <<Potentially_Use_Visible_Entity
>> declare
5317 Only_One_Visible
: Boolean := True;
5318 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5322 while Present
(E2
) loop
5323 if Is_Immediately_Visible
(E2
) then
5325 -- If the use-visible entity comes from the actual for a
5326 -- formal package, it hides a directly visible entity from
5327 -- outside the instance.
5329 if From_Actual_Package
(E
)
5330 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5335 goto Immediately_Visible_Entity
;
5338 elsif Is_Potentially_Use_Visible
(E2
) then
5339 Only_One_Visible
:= False;
5340 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5342 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5343 -- that can occur in private_with clauses. Example:
5346 -- private with B; package A is
5347 -- package C is function B return Integer;
5349 -- V1 : Integer := B;
5350 -- private function B return Integer;
5351 -- V2 : Integer := B;
5354 -- V1 resolves to A.B, but V2 resolves to library unit B
5356 elsif Ekind
(E2
) = E_Function
5357 and then Scope
(E2
) = Standard_Standard
5358 and then Has_Private_With
(E2
)
5360 Only_One_Visible
:= False;
5361 All_Overloadable
:= False;
5362 Nvis_Is_Private_Subprg
:= True;
5369 -- On falling through this loop, we have checked that there are no
5370 -- immediately visible entities. Only_One_Visible is set if exactly
5371 -- one potentially use visible entity exists. All_Overloadable is
5372 -- set if all the potentially use visible entities are overloadable.
5373 -- The condition for legality is that either there is one potentially
5374 -- use visible entity, or if there is more than one, then all of them
5375 -- are overloadable.
5377 if Only_One_Visible
or All_Overloadable
then
5380 -- If there is more than one potentially use-visible entity and at
5381 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5382 -- Note that E points to the first such entity on the homonym list.
5383 -- Special case: if one of the entities is declared in an actual
5384 -- package, it was visible in the generic, and takes precedence over
5385 -- other entities that are potentially use-visible. Same if it is
5386 -- declared in a local instantiation of the current instance.
5391 -- Find current instance
5393 Inst
:= Current_Scope
;
5394 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5395 if Is_Generic_Instance
(Inst
) then
5399 Inst
:= Scope
(Inst
);
5403 while Present
(E2
) loop
5404 if From_Actual_Package
(E2
)
5406 (Is_Generic_Instance
(Scope
(E2
))
5407 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5420 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5422 -- A use-clause in the body of a system file creates conflict
5423 -- with some entity in a user scope, while rtsfind is active.
5424 -- Keep only the entity coming from another predefined unit.
5427 while Present
(E2
) loop
5428 if Is_Predefined_File_Name
5429 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5438 -- Entity must exist because predefined unit is correct
5440 raise Program_Error
;
5449 -- Come here with E set to the first immediately visible entity on
5450 -- the homonym chain. This is the one we want unless there is another
5451 -- immediately visible entity further on in the chain for an inner
5452 -- scope (RM 8.3(8)).
5454 <<Immediately_Visible_Entity
>> declare
5459 -- Find scope level of initial entity. When compiling through
5460 -- Rtsfind, the previous context is not completely invisible, and
5461 -- an outer entity may appear on the chain, whose scope is below
5462 -- the entry for Standard that delimits the current scope stack.
5463 -- Indicate that the level for this spurious entry is outside of
5464 -- the current scope stack.
5466 Level
:= Scope_Stack
.Last
;
5468 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5469 exit when Scop
= Scope
(E
);
5471 exit when Scop
= Standard_Standard
;
5474 -- Now search remainder of homonym chain for more inner entry
5475 -- If the entity is Standard itself, it has no scope, and we
5476 -- compare it with the stack entry directly.
5479 while Present
(E2
) loop
5480 if Is_Immediately_Visible
(E2
) then
5482 -- If a generic package contains a local declaration that
5483 -- has the same name as the generic, there may be a visibility
5484 -- conflict in an instance, where the local declaration must
5485 -- also hide the name of the corresponding package renaming.
5486 -- We check explicitly for a package declared by a renaming,
5487 -- whose renamed entity is an instance that is on the scope
5488 -- stack, and that contains a homonym in the same scope. Once
5489 -- we have found it, we know that the package renaming is not
5490 -- immediately visible, and that the identifier denotes the
5491 -- other entity (and its homonyms if overloaded).
5493 if Scope
(E
) = Scope
(E2
)
5494 and then Ekind
(E
) = E_Package
5495 and then Present
(Renamed_Object
(E
))
5496 and then Is_Generic_Instance
(Renamed_Object
(E
))
5497 and then In_Open_Scopes
(Renamed_Object
(E
))
5498 and then Comes_From_Source
(N
)
5500 Set_Is_Immediately_Visible
(E
, False);
5504 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5505 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5506 or else Scope_Stack
.Table
(J
).Entity
= E2
5519 -- At the end of that loop, E is the innermost immediately
5520 -- visible entity, so we are all set.
5523 -- Come here with entity found, and stored in E
5527 -- Check violation of No_Wide_Characters restriction
5529 Check_Wide_Character_Restriction
(E
, N
);
5531 -- When distribution features are available (Get_PCS_Name /=
5532 -- Name_No_DSA), a remote access-to-subprogram type is converted
5533 -- into a record type holding whatever information is needed to
5534 -- perform a remote call on an RCI subprogram. In that case we
5535 -- rewrite any occurrence of the RAS type into the equivalent record
5536 -- type here. 'Access attribute references and RAS dereferences are
5537 -- then implemented using specific TSSs. However when distribution is
5538 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5539 -- generation of these TSSs, and we must keep the RAS type in its
5540 -- original access-to-subprogram form (since all calls through a
5541 -- value of such type will be local anyway in the absence of a PCS).
5543 if Comes_From_Source
(N
)
5544 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5545 and then Ekind
(E
) = E_Access_Subprogram_Type
5546 and then Expander_Active
5547 and then Get_PCS_Name
/= Name_No_DSA
5549 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5553 -- Set the entity. Note that the reason we call Set_Entity for the
5554 -- overloadable case, as opposed to Set_Entity_With_Checks is
5555 -- that in the overloaded case, the initial call can set the wrong
5556 -- homonym. The call that sets the right homonym is in Sem_Res and
5557 -- that call does use Set_Entity_With_Checks, so we don't miss
5560 if Is_Overloadable
(E
) then
5563 Set_Entity_With_Checks
(N
, E
);
5569 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5572 if Debug_Flag_E
then
5573 Write_Str
(" found ");
5574 Write_Entity_Info
(E
, " ");
5577 -- If the Ekind of the entity is Void, it means that all homonyms
5578 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5579 -- test is skipped if the current scope is a record and the name is
5580 -- a pragma argument expression (case of Atomic and Volatile pragmas
5581 -- and possibly other similar pragmas added later, which are allowed
5582 -- to reference components in the current record).
5584 if Ekind
(E
) = E_Void
5586 (not Is_Record_Type
(Current_Scope
)
5587 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5589 Premature_Usage
(N
);
5591 -- If the entity is overloadable, collect all interpretations of the
5592 -- name for subsequent overload resolution. We optimize a bit here to
5593 -- do this only if we have an overloadable entity that is not on its
5594 -- own on the homonym chain.
5596 elsif Is_Overloadable
(E
)
5597 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5599 Collect_Interps
(N
);
5601 -- If no homonyms were visible, the entity is unambiguous
5603 if not Is_Overloaded
(N
) then
5604 if not Is_Actual_Parameter
then
5605 Generate_Reference
(E
, N
);
5609 -- Case of non-overloadable entity, set the entity providing that
5610 -- we do not have the case of a discriminant reference within a
5611 -- default expression. Such references are replaced with the
5612 -- corresponding discriminal, which is the formal corresponding to
5613 -- to the discriminant in the initialization procedure.
5616 -- Entity is unambiguous, indicate that it is referenced here
5618 -- For a renaming of an object, always generate simple reference,
5619 -- we don't try to keep track of assignments in this case, except
5620 -- in SPARK mode where renamings are traversed for generating
5621 -- local effects of subprograms.
5624 and then Present
(Renamed_Object
(E
))
5625 and then not GNATprove_Mode
5627 Generate_Reference
(E
, N
);
5629 -- If the renamed entity is a private protected component,
5630 -- reference the original component as well. This needs to be
5631 -- done because the private renamings are installed before any
5632 -- analysis has occurred. Reference to a private component will
5633 -- resolve to the renaming and the original component will be
5634 -- left unreferenced, hence the following.
5636 if Is_Prival
(E
) then
5637 Generate_Reference
(Prival_Link
(E
), N
);
5640 -- One odd case is that we do not want to set the Referenced flag
5641 -- if the entity is a label, and the identifier is the label in
5642 -- the source, since this is not a reference from the point of
5643 -- view of the user.
5645 elsif Nkind
(Parent
(N
)) = N_Label
then
5647 R
: constant Boolean := Referenced
(E
);
5650 -- Generate reference unless this is an actual parameter
5651 -- (see comment below)
5653 if Is_Actual_Parameter
then
5654 Generate_Reference
(E
, N
);
5655 Set_Referenced
(E
, R
);
5659 -- Normal case, not a label: generate reference
5662 if not Is_Actual_Parameter
then
5664 -- Package or generic package is always a simple reference
5666 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5667 Generate_Reference
(E
, N
, 'r');
5669 -- Else see if we have a left hand side
5674 Generate_Reference
(E
, N
, 'm');
5677 Generate_Reference
(E
, N
, 'r');
5679 -- If we don't know now, generate reference later
5682 Deferred_References
.Append
((E
, N
));
5687 Check_Nested_Access
(E
);
5690 Set_Entity_Or_Discriminal
(N
, E
);
5692 -- The name may designate a generalized reference, in which case
5693 -- the dereference interpretation will be included.
5695 if Ada_Version
>= Ada_2012
5697 (Nkind
(Parent
(N
)) in N_Subexpr
5698 or else Nkind_In
(Parent
(N
), N_Object_Declaration
,
5699 N_Assignment_Statement
))
5701 Check_Implicit_Dereference
(N
, Etype
(E
));
5706 -- Come here with entity set
5709 Check_Restriction_No_Use_Of_Entity
(N
);
5710 end Find_Direct_Name
;
5712 ------------------------
5713 -- Find_Expanded_Name --
5714 ------------------------
5716 -- This routine searches the homonym chain of the entity until it finds
5717 -- an entity declared in the scope denoted by the prefix. If the entity
5718 -- is private, it may nevertheless be immediately visible, if we are in
5719 -- the scope of its declaration.
5721 procedure Find_Expanded_Name
(N
: Node_Id
) is
5722 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean;
5723 -- Determine whether an arbitrary node N appears in pragmas [Refined_]
5724 -- Depends or [Refined_]Global.
5726 ----------------------------------
5727 -- In_Pragmas_Depends_Or_Global --
5728 ----------------------------------
5730 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean is
5734 -- Climb the parent chain looking for a pragma
5737 while Present
(Par
) loop
5738 if Nkind
(Par
) = N_Pragma
5739 and then Nam_In
(Pragma_Name
(Par
), Name_Depends
,
5741 Name_Refined_Depends
,
5742 Name_Refined_Global
)
5746 -- Prevent the search from going too far
5748 elsif Is_Body_Or_Package_Declaration
(Par
) then
5752 Par
:= Parent
(Par
);
5756 end In_Pragmas_Depends_Or_Global
;
5760 Selector
: constant Node_Id
:= Selector_Name
(N
);
5761 Candidate
: Entity_Id
:= Empty
;
5765 -- Start of processing for Find_Expanded_Name
5768 P_Name
:= Entity
(Prefix
(N
));
5770 -- If the prefix is a renamed package, look for the entity in the
5771 -- original package.
5773 if Ekind
(P_Name
) = E_Package
5774 and then Present
(Renamed_Object
(P_Name
))
5776 P_Name
:= Renamed_Object
(P_Name
);
5778 -- Rewrite node with entity field pointing to renamed object
5780 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5781 Set_Entity
(Prefix
(N
), P_Name
);
5783 -- If the prefix is an object of a concurrent type, look for
5784 -- the entity in the associated task or protected type.
5786 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5787 P_Name
:= Etype
(P_Name
);
5790 Id
:= Current_Entity
(Selector
);
5793 Is_New_Candidate
: Boolean;
5796 while Present
(Id
) loop
5797 if Scope
(Id
) = P_Name
then
5799 Is_New_Candidate
:= True;
5801 -- Handle abstract views of states and variables. These are
5802 -- acceptable only when the reference to the view appears in
5803 -- pragmas [Refined_]Depends and [Refined_]Global.
5805 if Ekind
(Id
) = E_Abstract_State
5806 and then From_Limited_With
(Id
)
5807 and then Present
(Non_Limited_View
(Id
))
5809 if In_Pragmas_Depends_Or_Global
(N
) then
5810 Candidate
:= Non_Limited_View
(Id
);
5811 Is_New_Candidate
:= True;
5813 -- Hide candidate because it is not used in a proper context
5817 Is_New_Candidate
:= False;
5821 -- Ada 2005 (AI-217): Handle shadow entities associated with
5822 -- types declared in limited-withed nested packages. We don't need
5823 -- to handle E_Incomplete_Subtype entities because the entities
5824 -- in the limited view are always E_Incomplete_Type and
5825 -- E_Class_Wide_Type entities (see Build_Limited_Views).
5827 -- Regarding the expression used to evaluate the scope, it
5828 -- is important to note that the limited view also has shadow
5829 -- entities associated nested packages. For this reason the
5830 -- correct scope of the entity is the scope of the real entity.
5831 -- The non-limited view may itself be incomplete, in which case
5832 -- get the full view if available.
5834 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
5835 and then From_Limited_With
(Id
)
5836 and then Present
(Non_Limited_View
(Id
))
5837 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5839 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5840 Is_New_Candidate
:= True;
5843 Is_New_Candidate
:= False;
5846 if Is_New_Candidate
then
5848 -- If entity is a child unit, either it is a visible child of
5849 -- the prefix, or we are in the body of a generic prefix, as
5850 -- will happen when a child unit is instantiated in the body
5851 -- of a generic parent. This is because the instance body does
5852 -- not restore the full compilation context, given that all
5853 -- non-local references have been captured.
5855 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5856 exit when Is_Visible_Lib_Unit
(Id
)
5857 or else (Is_Child_Unit
(Id
)
5858 and then In_Open_Scopes
(Scope
(Id
))
5859 and then In_Instance_Body
);
5861 exit when not Is_Hidden
(Id
);
5864 exit when Is_Immediately_Visible
(Id
);
5872 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5873 and then Is_Generic_Instance
(P_Name
)
5875 -- Expanded name denotes entity in (instance of) generic subprogram.
5876 -- The entity may be in the subprogram instance, or may denote one of
5877 -- the formals, which is declared in the enclosing wrapper package.
5879 P_Name
:= Scope
(P_Name
);
5881 Id
:= Current_Entity
(Selector
);
5882 while Present
(Id
) loop
5883 exit when Scope
(Id
) = P_Name
;
5888 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5889 Set_Etype
(N
, Any_Type
);
5891 -- If we are looking for an entity defined in System, try to find it
5892 -- in the child package that may have been provided as an extension
5893 -- to System. The Extend_System pragma will have supplied the name of
5894 -- the extension, which may have to be loaded.
5896 if Chars
(P_Name
) = Name_System
5897 and then Scope
(P_Name
) = Standard_Standard
5898 and then Present
(System_Extend_Unit
)
5899 and then Present_System_Aux
(N
)
5901 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5902 Find_Expanded_Name
(N
);
5905 elsif Nkind
(Selector
) = N_Operator_Symbol
5906 and then Has_Implicit_Operator
(N
)
5908 -- There is an implicit instance of the predefined operator in
5909 -- the given scope. The operator entity is defined in Standard.
5910 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5914 elsif Nkind
(Selector
) = N_Character_Literal
5915 and then Has_Implicit_Character_Literal
(N
)
5917 -- If there is no literal defined in the scope denoted by the
5918 -- prefix, the literal may belong to (a type derived from)
5919 -- Standard_Character, for which we have no explicit literals.
5924 -- If the prefix is a single concurrent object, use its name in
5925 -- the error message, rather than that of the anonymous type.
5927 if Is_Concurrent_Type
(P_Name
)
5928 and then Is_Internal_Name
(Chars
(P_Name
))
5930 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5932 Error_Msg_Node_2
:= P_Name
;
5935 if P_Name
= System_Aux_Id
then
5936 P_Name
:= Scope
(P_Name
);
5937 Set_Entity
(Prefix
(N
), P_Name
);
5940 if Present
(Candidate
) then
5942 -- If we know that the unit is a child unit we can give a more
5943 -- accurate error message.
5945 if Is_Child_Unit
(Candidate
) then
5947 -- If the candidate is a private child unit and we are in
5948 -- the visible part of a public unit, specialize the error
5949 -- message. There might be a private with_clause for it,
5950 -- but it is not currently active.
5952 if Is_Private_Descendant
(Candidate
)
5953 and then Ekind
(Current_Scope
) = E_Package
5954 and then not In_Private_Part
(Current_Scope
)
5955 and then not Is_Private_Descendant
(Current_Scope
)
5957 Error_Msg_N
("private child unit& is not visible here",
5960 -- Normal case where we have a missing with for a child unit
5963 Error_Msg_Qual_Level
:= 99;
5964 Error_Msg_NE
-- CODEFIX
5965 ("missing `WITH &;`", Selector
, Candidate
);
5966 Error_Msg_Qual_Level
:= 0;
5969 -- Here we don't know that this is a child unit
5972 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5976 -- Within the instantiation of a child unit, the prefix may
5977 -- denote the parent instance, but the selector has the name
5978 -- of the original child. That is to say, when A.B appears
5979 -- within an instantiation of generic child unit B, the scope
5980 -- stack includes an instance of A (P_Name) and an instance
5981 -- of B under some other name. We scan the scope to find this
5982 -- child instance, which is the desired entity.
5983 -- Note that the parent may itself be a child instance, if
5984 -- the reference is of the form A.B.C, in which case A.B has
5985 -- already been rewritten with the proper entity.
5987 if In_Open_Scopes
(P_Name
)
5988 and then Is_Generic_Instance
(P_Name
)
5991 Gen_Par
: constant Entity_Id
:=
5992 Generic_Parent
(Specification
5993 (Unit_Declaration_Node
(P_Name
)));
5994 S
: Entity_Id
:= Current_Scope
;
5998 for J
in reverse 0 .. Scope_Stack
.Last
loop
5999 S
:= Scope_Stack
.Table
(J
).Entity
;
6001 exit when S
= Standard_Standard
;
6003 if Ekind_In
(S
, E_Function
,
6007 P
:= Generic_Parent
(Specification
6008 (Unit_Declaration_Node
(S
)));
6010 -- Check that P is a generic child of the generic
6011 -- parent of the prefix.
6014 and then Chars
(P
) = Chars
(Selector
)
6015 and then Scope
(P
) = Gen_Par
6026 -- If this is a selection from Ada, System or Interfaces, then
6027 -- we assume a missing with for the corresponding package.
6029 if Is_Known_Unit
(N
) then
6030 if not Error_Posted
(N
) then
6031 Error_Msg_Node_2
:= Selector
;
6032 Error_Msg_N
-- CODEFIX
6033 ("missing `WITH &.&;`", Prefix
(N
));
6036 -- If this is a selection from a dummy package, then suppress
6037 -- the error message, of course the entity is missing if the
6038 -- package is missing.
6040 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
6043 -- Here we have the case of an undefined component
6047 -- The prefix may hide a homonym in the context that
6048 -- declares the desired entity. This error can use a
6049 -- specialized message.
6051 if In_Open_Scopes
(P_Name
) then
6053 H
: constant Entity_Id
:= Homonym
(P_Name
);
6057 and then Is_Compilation_Unit
(H
)
6059 (Is_Immediately_Visible
(H
)
6060 or else Is_Visible_Lib_Unit
(H
))
6062 Id
:= First_Entity
(H
);
6063 while Present
(Id
) loop
6064 if Chars
(Id
) = Chars
(Selector
) then
6065 Error_Msg_Qual_Level
:= 99;
6066 Error_Msg_Name_1
:= Chars
(Selector
);
6068 ("% not declared in&", N
, P_Name
);
6070 ("\use fully qualified name starting with "
6071 & "Standard to make& visible", N
, H
);
6072 Error_Msg_Qual_Level
:= 0;
6080 -- If not found, standard error message
6082 Error_Msg_NE
("& not declared in&", N
, Selector
);
6088 Error_Msg_NE
("& not declared in&", N
, Selector
);
6091 -- Check for misspelling of some entity in prefix
6093 Id
:= First_Entity
(P_Name
);
6094 while Present
(Id
) loop
6095 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6096 and then not Is_Internal_Name
(Chars
(Id
))
6098 Error_Msg_NE
-- CODEFIX
6099 ("possible misspelling of&", Selector
, Id
);
6106 -- Specialize the message if this may be an instantiation
6107 -- of a child unit that was not mentioned in the context.
6109 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6110 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6111 and then Is_Compilation_Unit
6112 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6114 Error_Msg_Node_2
:= Selector
;
6115 Error_Msg_N
-- CODEFIX
6116 ("\missing `WITH &.&;`", Prefix
(N
));
6126 if Comes_From_Source
(N
)
6127 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6128 and then Ekind
(Id
) = E_Access_Subprogram_Type
6129 and then Present
(Equivalent_Type
(Id
))
6131 -- If we are not actually generating distribution code (i.e. the
6132 -- current PCS is the dummy non-distributed version), then the
6133 -- Equivalent_Type will be missing, and Id should be treated as
6134 -- a regular access-to-subprogram type.
6136 Id
:= Equivalent_Type
(Id
);
6137 Set_Chars
(Selector
, Chars
(Id
));
6140 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6142 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6143 if From_Limited_With
(Id
)
6144 or else Is_Type
(Id
)
6145 or else Ekind
(Id
) = E_Package
6150 ("limited withed package can only be used to access "
6151 & "incomplete types", N
);
6155 if Is_Task_Type
(P_Name
)
6156 and then ((Ekind
(Id
) = E_Entry
6157 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6159 (Ekind
(Id
) = E_Entry_Family
6161 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6163 -- If both the task type and the entry are in scope, this may still
6164 -- be the expanded name of an entry formal.
6166 if In_Open_Scopes
(Id
)
6167 and then Nkind
(Parent
(N
)) = N_Selected_Component
6172 -- It is an entry call after all, either to the current task
6173 -- (which will deadlock) or to an enclosing task.
6175 Analyze_Selected_Component
(N
);
6180 Change_Selected_Component_To_Expanded_Name
(N
);
6182 -- Set appropriate type
6184 if Is_Type
(Id
) then
6187 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6190 -- Do style check and generate reference, but skip both steps if this
6191 -- entity has homonyms, since we may not have the right homonym set yet.
6192 -- The proper homonym will be set during the resolve phase.
6194 if Has_Homonym
(Id
) then
6198 Set_Entity_Or_Discriminal
(N
, Id
);
6202 Generate_Reference
(Id
, N
, 'm');
6204 Generate_Reference
(Id
, N
, 'r');
6206 Deferred_References
.Append
((Id
, N
));
6210 -- Check for violation of No_Wide_Characters
6212 Check_Wide_Character_Restriction
(Id
, N
);
6214 -- If the Ekind of the entity is Void, it means that all homonyms are
6215 -- hidden from all visibility (RM 8.3(5,14-20)).
6217 if Ekind
(Id
) = E_Void
then
6218 Premature_Usage
(N
);
6220 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6222 H
: Entity_Id
:= Homonym
(Id
);
6225 while Present
(H
) loop
6226 if Scope
(H
) = Scope
(Id
)
6227 and then (not Is_Hidden
(H
)
6228 or else Is_Immediately_Visible
(H
))
6230 Collect_Interps
(N
);
6237 -- If an extension of System is present, collect possible explicit
6238 -- overloadings declared in the extension.
6240 if Chars
(P_Name
) = Name_System
6241 and then Scope
(P_Name
) = Standard_Standard
6242 and then Present
(System_Extend_Unit
)
6243 and then Present_System_Aux
(N
)
6245 H
:= Current_Entity
(Id
);
6247 while Present
(H
) loop
6248 if Scope
(H
) = System_Aux_Id
then
6249 Add_One_Interp
(N
, H
, Etype
(H
));
6258 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6259 and then Scope
(Id
) /= Standard_Standard
6261 -- In addition to user-defined operators in the given scope, there
6262 -- may be an implicit instance of the predefined operator. The
6263 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6264 -- and added to the interpretations. Procedure Add_One_Interp will
6265 -- determine which hides which.
6267 if Has_Implicit_Operator
(N
) then
6272 -- If there is a single interpretation for N we can generate a
6273 -- reference to the unique entity found.
6275 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6276 Generate_Reference
(Id
, N
);
6278 end Find_Expanded_Name
;
6280 -------------------------
6281 -- Find_Renamed_Entity --
6282 -------------------------
6284 function Find_Renamed_Entity
6288 Is_Actual
: Boolean := False) return Entity_Id
6291 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6297 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6298 -- If the renamed entity is an implicit operator, check whether it is
6299 -- visible because its operand type is properly visible. This check
6300 -- applies to explicit renamed entities that appear in the source in a
6301 -- renaming declaration or a formal subprogram instance, but not to
6302 -- default generic actuals with a name.
6304 function Report_Overload
return Entity_Id
;
6305 -- List possible interpretations, and specialize message in the
6306 -- case of a generic actual.
6308 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6309 -- Determine whether a candidate subprogram is defined within the
6310 -- enclosing instance. If yes, it has precedence over outer candidates.
6312 --------------------------
6313 -- Is_Visible_Operation --
6314 --------------------------
6316 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6322 if Ekind
(Op
) /= E_Operator
6323 or else Scope
(Op
) /= Standard_Standard
6324 or else (In_Instance
6325 and then (not Is_Actual
6326 or else Present
(Enclosing_Instance
)))
6331 -- For a fixed point type operator, check the resulting type,
6332 -- because it may be a mixed mode integer * fixed operation.
6334 if Present
(Next_Formal
(First_Formal
(New_S
)))
6335 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6337 Typ
:= Etype
(New_S
);
6339 Typ
:= Etype
(First_Formal
(New_S
));
6342 Btyp
:= Base_Type
(Typ
);
6344 if Nkind
(Nam
) /= N_Expanded_Name
then
6345 return (In_Open_Scopes
(Scope
(Btyp
))
6346 or else Is_Potentially_Use_Visible
(Btyp
)
6347 or else In_Use
(Btyp
)
6348 or else In_Use
(Scope
(Btyp
)));
6351 Scop
:= Entity
(Prefix
(Nam
));
6353 if Ekind
(Scop
) = E_Package
6354 and then Present
(Renamed_Object
(Scop
))
6356 Scop
:= Renamed_Object
(Scop
);
6359 -- Operator is visible if prefix of expanded name denotes
6360 -- scope of type, or else type is defined in System_Aux
6361 -- and the prefix denotes System.
6363 return Scope
(Btyp
) = Scop
6364 or else (Scope
(Btyp
) = System_Aux_Id
6365 and then Scope
(Scope
(Btyp
)) = Scop
);
6368 end Is_Visible_Operation
;
6374 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6378 Sc
:= Scope
(Inner
);
6379 while Sc
/= Standard_Standard
loop
6390 ---------------------
6391 -- Report_Overload --
6392 ---------------------
6394 function Report_Overload
return Entity_Id
is
6397 Error_Msg_NE
-- CODEFIX
6398 ("ambiguous actual subprogram&, " &
6399 "possible interpretations:", N
, Nam
);
6401 Error_Msg_N
-- CODEFIX
6402 ("ambiguous subprogram, " &
6403 "possible interpretations:", N
);
6406 List_Interps
(Nam
, N
);
6408 end Report_Overload
;
6410 -- Start of processing for Find_Renamed_Entity
6414 Candidate_Renaming
:= Empty
;
6416 if Is_Overloaded
(Nam
) then
6417 Get_First_Interp
(Nam
, Ind
, It
);
6418 while Present
(It
.Nam
) loop
6419 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6420 and then Is_Visible_Operation
(It
.Nam
)
6422 if Old_S
/= Any_Id
then
6424 -- Note: The call to Disambiguate only happens if a
6425 -- previous interpretation was found, in which case I1
6426 -- has received a value.
6428 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6430 if It1
= No_Interp
then
6431 Inst
:= Enclosing_Instance
;
6433 if Present
(Inst
) then
6434 if Within
(It
.Nam
, Inst
) then
6435 if Within
(Old_S
, Inst
) then
6437 -- Choose the innermost subprogram, which would
6438 -- have hidden the outer one in the generic.
6440 if Scope_Depth
(It
.Nam
) <
6449 elsif Within
(Old_S
, Inst
) then
6453 return Report_Overload
;
6456 -- If not within an instance, ambiguity is real
6459 return Report_Overload
;
6473 Present
(First_Formal
(It
.Nam
))
6474 and then Present
(First_Formal
(New_S
))
6475 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6476 Base_Type
(Etype
(First_Formal
(New_S
))))
6478 Candidate_Renaming
:= It
.Nam
;
6481 Get_Next_Interp
(Ind
, It
);
6484 Set_Entity
(Nam
, Old_S
);
6486 if Old_S
/= Any_Id
then
6487 Set_Is_Overloaded
(Nam
, False);
6490 -- Non-overloaded case
6493 if Is_Actual
and then Present
(Enclosing_Instance
) then
6494 Old_S
:= Entity
(Nam
);
6496 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6497 Candidate_Renaming
:= New_S
;
6499 if Is_Visible_Operation
(Entity
(Nam
)) then
6500 Old_S
:= Entity
(Nam
);
6503 elsif Present
(First_Formal
(Entity
(Nam
)))
6504 and then Present
(First_Formal
(New_S
))
6505 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6506 Base_Type
(Etype
(First_Formal
(New_S
))))
6508 Candidate_Renaming
:= Entity
(Nam
);
6513 end Find_Renamed_Entity
;
6515 -----------------------------
6516 -- Find_Selected_Component --
6517 -----------------------------
6519 procedure Find_Selected_Component
(N
: Node_Id
) is
6520 P
: constant Node_Id
:= Prefix
(N
);
6523 -- Entity denoted by prefix
6530 function Available_Subtype
return Boolean;
6531 -- A small optimization: if the prefix is constrained and the component
6532 -- is an array type we may already have a usable subtype for it, so we
6533 -- can use it rather than generating a new one, because the bounds
6534 -- will be the values of the discriminants and not discriminant refs.
6535 -- This simplifies value tracing in GNATProve. For consistency, both
6536 -- the entity name and the subtype come from the constrained component.
6538 function Is_Reference_In_Subunit
return Boolean;
6539 -- In a subunit, the scope depth is not a proper measure of hiding,
6540 -- because the context of the proper body may itself hide entities in
6541 -- parent units. This rare case requires inspecting the tree directly
6542 -- because the proper body is inserted in the main unit and its context
6543 -- is simply added to that of the parent.
6545 -----------------------
6546 -- Available_Subtype --
6547 -----------------------
6549 function Available_Subtype
return Boolean is
6553 Comp
:= First_Entity
(Etype
(P
));
6554 while Present
(Comp
) loop
6555 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6556 Set_Etype
(N
, Etype
(Comp
));
6557 Set_Entity
(Selector_Name
(N
), Comp
);
6558 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6562 Next_Component
(Comp
);
6566 end Available_Subtype
;
6568 -----------------------------
6569 -- Is_Reference_In_Subunit --
6570 -----------------------------
6572 function Is_Reference_In_Subunit
return Boolean is
6574 Comp_Unit
: Node_Id
;
6578 while Present
(Comp_Unit
)
6579 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6581 Comp_Unit
:= Parent
(Comp_Unit
);
6584 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6588 -- Now check whether the package is in the context of the subunit
6590 Clause
:= First
(Context_Items
(Comp_Unit
));
6591 while Present
(Clause
) loop
6592 if Nkind
(Clause
) = N_With_Clause
6593 and then Entity
(Name
(Clause
)) = P_Name
6598 Clause
:= Next
(Clause
);
6602 end Is_Reference_In_Subunit
;
6604 -- Start of processing for Find_Selected_Component
6609 if Nkind
(P
) = N_Error
then
6613 -- Selector name cannot be a character literal or an operator symbol in
6614 -- SPARK, except for the operator symbol in a renaming.
6616 if Restriction_Check_Required
(SPARK_05
) then
6617 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6618 Check_SPARK_05_Restriction
6619 ("character literal cannot be prefixed", N
);
6620 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6621 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6623 Check_SPARK_05_Restriction
6624 ("operator symbol cannot be prefixed", N
);
6628 -- If the selector already has an entity, the node has been constructed
6629 -- in the course of expansion, and is known to be valid. Do not verify
6630 -- that it is defined for the type (it may be a private component used
6631 -- in the expansion of record equality).
6633 if Present
(Entity
(Selector_Name
(N
))) then
6634 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6636 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6637 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6641 Set_Etype
(Sel_Name
, Etype
(Selector
));
6643 if not Is_Entity_Name
(P
) then
6647 -- Build an actual subtype except for the first parameter
6648 -- of an init proc, where this actual subtype is by
6649 -- definition incorrect, since the object is uninitialized
6650 -- (and does not even have defined discriminants etc.)
6652 if Is_Entity_Name
(P
)
6653 and then Ekind
(Entity
(P
)) = E_Function
6655 Nam
:= New_Copy
(P
);
6657 if Is_Overloaded
(P
) then
6658 Save_Interps
(P
, Nam
);
6661 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6663 Analyze_Selected_Component
(N
);
6666 elsif Ekind
(Selector
) = E_Component
6667 and then (not Is_Entity_Name
(P
)
6668 or else Chars
(Entity
(P
)) /= Name_uInit
)
6670 -- Check if we already have an available subtype we can use
6672 if Ekind
(Etype
(P
)) = E_Record_Subtype
6673 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6674 and then Is_Array_Type
(Etype
(Selector
))
6675 and then not Is_Packed
(Etype
(Selector
))
6676 and then Available_Subtype
6680 -- Do not build the subtype when referencing components of
6681 -- dispatch table wrappers. Required to avoid generating
6682 -- elaboration code with HI runtimes. JVM and .NET use a
6683 -- modified version of Ada.Tags which does not contain RE_
6684 -- Dispatch_Table_Wrapper and RE_No_Dispatch_Table_Wrapper.
6685 -- Avoid raising RE_Not_Available exception in those cases.
6687 elsif VM_Target
= No_VM
6688 and then RTU_Loaded
(Ada_Tags
)
6690 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6691 and then Scope
(Selector
) =
6692 RTE
(RE_Dispatch_Table_Wrapper
))
6694 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6695 and then Scope
(Selector
) =
6696 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6701 Build_Actual_Subtype_Of_Component
6702 (Etype
(Selector
), N
);
6709 if No
(C_Etype
) then
6710 C_Etype
:= Etype
(Selector
);
6712 Insert_Action
(N
, C_Etype
);
6713 C_Etype
:= Defining_Identifier
(C_Etype
);
6716 Set_Etype
(N
, C_Etype
);
6719 -- If this is the name of an entry or protected operation, and
6720 -- the prefix is an access type, insert an explicit dereference,
6721 -- so that entry calls are treated uniformly.
6723 if Is_Access_Type
(Etype
(P
))
6724 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6727 New_P
: constant Node_Id
:=
6728 Make_Explicit_Dereference
(Sloc
(P
),
6729 Prefix
=> Relocate_Node
(P
));
6732 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6736 -- If the selected component appears within a default expression
6737 -- and it has an actual subtype, the pre-analysis has not yet
6738 -- completed its analysis, because Insert_Actions is disabled in
6739 -- that context. Within the init proc of the enclosing type we
6740 -- must complete this analysis, if an actual subtype was created.
6742 elsif Inside_Init_Proc
then
6744 Typ
: constant Entity_Id
:= Etype
(N
);
6745 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6747 if Nkind
(Decl
) = N_Subtype_Declaration
6748 and then not Analyzed
(Decl
)
6749 and then Is_List_Member
(Decl
)
6750 and then No
(Parent
(Decl
))
6753 Insert_Action
(N
, Decl
);
6760 elsif Is_Entity_Name
(P
) then
6761 P_Name
:= Entity
(P
);
6763 -- The prefix may denote an enclosing type which is the completion
6764 -- of an incomplete type declaration.
6766 if Is_Type
(P_Name
) then
6767 Set_Entity
(P
, Get_Full_View
(P_Name
));
6768 Set_Etype
(P
, Entity
(P
));
6769 P_Name
:= Entity
(P
);
6772 P_Type
:= Base_Type
(Etype
(P
));
6774 if Debug_Flag_E
then
6775 Write_Str
("Found prefix type to be ");
6776 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6779 -- The designated type may be a limited view with no components.
6780 -- Check whether the non-limited view is available, because in some
6781 -- cases this will not be set when installing the context.
6783 if Is_Access_Type
(P_Type
) then
6785 D
: constant Entity_Id
:= Directly_Designated_Type
(P_Type
);
6787 if Is_Incomplete_Type
(D
)
6788 and then From_Limited_With
(D
)
6789 and then Present
(Non_Limited_View
(D
))
6791 Set_Directly_Designated_Type
(P_Type
, Non_Limited_View
(D
));
6796 -- First check for components of a record object (not the
6797 -- result of a call, which is handled below).
6799 if Is_Appropriate_For_Record
(P_Type
)
6800 and then not Is_Overloadable
(P_Name
)
6801 and then not Is_Type
(P_Name
)
6803 -- Selected component of record. Type checking will validate
6804 -- name of selector.
6806 -- ??? Could we rewrite an implicit dereference into an explicit
6809 Analyze_Selected_Component
(N
);
6811 -- Reference to type name in predicate/invariant expression
6813 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6814 and then not In_Open_Scopes
(P_Name
)
6815 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6816 or else not In_Open_Scopes
(Etype
(P_Name
)))
6818 -- Call to protected operation or entry. Type checking is
6819 -- needed on the prefix.
6821 Analyze_Selected_Component
(N
);
6823 elsif (In_Open_Scopes
(P_Name
)
6824 and then Ekind
(P_Name
) /= E_Void
6825 and then not Is_Overloadable
(P_Name
))
6826 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6827 and then In_Open_Scopes
(Etype
(P_Name
)))
6829 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6830 -- enclosing construct that is not a subprogram or accept.
6832 Find_Expanded_Name
(N
);
6834 elsif Ekind
(P_Name
) = E_Package
then
6835 Find_Expanded_Name
(N
);
6837 elsif Is_Overloadable
(P_Name
) then
6839 -- The subprogram may be a renaming (of an enclosing scope) as
6840 -- in the case of the name of the generic within an instantiation.
6842 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6843 and then Present
(Alias
(P_Name
))
6844 and then Is_Generic_Instance
(Alias
(P_Name
))
6846 P_Name
:= Alias
(P_Name
);
6849 if Is_Overloaded
(P
) then
6851 -- The prefix must resolve to a unique enclosing construct
6854 Found
: Boolean := False;
6859 Get_First_Interp
(P
, Ind
, It
);
6860 while Present
(It
.Nam
) loop
6861 if In_Open_Scopes
(It
.Nam
) then
6864 "prefix must be unique enclosing scope", N
);
6865 Set_Entity
(N
, Any_Id
);
6866 Set_Etype
(N
, Any_Type
);
6875 Get_Next_Interp
(Ind
, It
);
6880 if In_Open_Scopes
(P_Name
) then
6881 Set_Entity
(P
, P_Name
);
6882 Set_Is_Overloaded
(P
, False);
6883 Find_Expanded_Name
(N
);
6886 -- If no interpretation as an expanded name is possible, it
6887 -- must be a selected component of a record returned by a
6888 -- function call. Reformat prefix as a function call, the rest
6889 -- is done by type resolution.
6891 -- Error if the prefix is procedure or entry, as is P.X
6893 if Ekind
(P_Name
) /= E_Function
6895 (not Is_Overloaded
(P
)
6896 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6898 -- Prefix may mention a package that is hidden by a local
6899 -- declaration: let the user know. Scan the full homonym
6900 -- chain, the candidate package may be anywhere on it.
6902 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6903 P_Name
:= Current_Entity
(P_Name
);
6905 while Present
(P_Name
) loop
6906 exit when Ekind
(P_Name
) = E_Package
;
6907 P_Name
:= Homonym
(P_Name
);
6910 if Present
(P_Name
) then
6911 if not Is_Reference_In_Subunit
then
6912 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6914 ("package& is hidden by declaration#", N
, P_Name
);
6917 Set_Entity
(Prefix
(N
), P_Name
);
6918 Find_Expanded_Name
(N
);
6922 P_Name
:= Entity
(Prefix
(N
));
6927 ("invalid prefix in selected component&", N
, P_Name
);
6928 Change_Selected_Component_To_Expanded_Name
(N
);
6929 Set_Entity
(N
, Any_Id
);
6930 Set_Etype
(N
, Any_Type
);
6932 -- Here we have a function call, so do the reformatting
6935 Nam
:= New_Copy
(P
);
6936 Save_Interps
(P
, Nam
);
6938 -- We use Replace here because this is one of those cases
6939 -- where the parser has missclassified the node, and we
6940 -- fix things up and then do the semantic analysis on the
6941 -- fixed up node. Normally we do this using one of the
6942 -- Sinfo.CN routines, but this is too tricky for that.
6944 -- Note that using Rewrite would be wrong, because we
6945 -- would have a tree where the original node is unanalyzed,
6946 -- and this violates the required interface for ASIS.
6949 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6951 -- Now analyze the reformatted node
6954 Analyze_Selected_Component
(N
);
6958 -- Remaining cases generate various error messages
6961 -- Format node as expanded name, to avoid cascaded errors
6963 Change_Selected_Component_To_Expanded_Name
(N
);
6964 Set_Entity
(N
, Any_Id
);
6965 Set_Etype
(N
, Any_Type
);
6967 -- Issue error message, but avoid this if error issued already.
6968 -- Use identifier of prefix if one is available.
6970 if P_Name
= Any_Id
then
6973 -- It is not an error if the prefix is the current instance of
6974 -- type name, e.g. the expression of a type aspect, when it is
6975 -- analyzed for ASIS use.
6977 elsif Is_Entity_Name
(P
) and then Is_Current_Instance
(P
) then
6980 elsif Ekind
(P_Name
) = E_Void
then
6981 Premature_Usage
(P
);
6983 elsif Nkind
(P
) /= N_Attribute_Reference
then
6985 -- This may have been meant as a prefixed call to a primitive
6986 -- of an untagged type.
6989 F
: constant Entity_Id
:=
6990 Current_Entity
(Selector_Name
(N
));
6993 and then Is_Overloadable
(F
)
6994 and then Present
(First_Entity
(F
))
6995 and then Etype
(First_Entity
(F
)) = Etype
(P
)
6996 and then not Is_Tagged_Type
(Etype
(P
))
6999 ("prefixed call is only allowed for objects "
7000 & "of a tagged type", N
);
7004 Error_Msg_N
("invalid prefix in selected component&", P
);
7006 if Is_Access_Type
(P_Type
)
7007 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
7010 ("\dereference must not be of an incomplete type "
7011 & "(RM 3.10.1)", P
);
7015 Error_Msg_N
("invalid prefix in selected component", P
);
7019 -- Selector name is restricted in SPARK
7021 if Nkind
(N
) = N_Expanded_Name
7022 and then Restriction_Check_Required
(SPARK_05
)
7024 if Is_Subprogram
(P_Name
) then
7025 Check_SPARK_05_Restriction
7026 ("prefix of expanded name cannot be a subprogram", P
);
7027 elsif Ekind
(P_Name
) = E_Loop
then
7028 Check_SPARK_05_Restriction
7029 ("prefix of expanded name cannot be a loop statement", P
);
7034 -- If prefix is not the name of an entity, it must be an expression,
7035 -- whose type is appropriate for a record. This is determined by
7038 Analyze_Selected_Component
(N
);
7041 Analyze_Dimension
(N
);
7042 end Find_Selected_Component
;
7048 procedure Find_Type
(N
: Node_Id
) is
7058 elsif Nkind
(N
) = N_Attribute_Reference
then
7060 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7061 -- need to enforce that at this point, since the declaration of the
7062 -- tagged type in the prefix would have been flagged already.
7064 if Attribute_Name
(N
) = Name_Class
then
7065 Check_Restriction
(No_Dispatch
, N
);
7066 Find_Type
(Prefix
(N
));
7068 -- Propagate error from bad prefix
7070 if Etype
(Prefix
(N
)) = Any_Type
then
7071 Set_Entity
(N
, Any_Type
);
7072 Set_Etype
(N
, Any_Type
);
7076 T
:= Base_Type
(Entity
(Prefix
(N
)));
7078 -- Case where type is not known to be tagged. Its appearance in
7079 -- the prefix of the 'Class attribute indicates that the full view
7082 if not Is_Tagged_Type
(T
) then
7083 if Ekind
(T
) = E_Incomplete_Type
then
7085 -- It is legal to denote the class type of an incomplete
7086 -- type. The full type will have to be tagged, of course.
7087 -- In Ada 2005 this usage is declared obsolescent, so we
7088 -- warn accordingly. This usage is only legal if the type
7089 -- is completed in the current scope, and not for a limited
7092 if Ada_Version
>= Ada_2005
then
7094 -- Test whether the Available_View of a limited type view
7095 -- is tagged, since the limited view may not be marked as
7096 -- tagged if the type itself has an untagged incomplete
7097 -- type view in its package.
7099 if From_Limited_With
(T
)
7100 and then not Is_Tagged_Type
(Available_View
(T
))
7103 ("prefix of Class attribute must be tagged", N
);
7104 Set_Etype
(N
, Any_Type
);
7105 Set_Entity
(N
, Any_Type
);
7108 -- ??? This test is temporarily disabled (always
7109 -- False) because it causes an unwanted warning on
7110 -- GNAT sources (built with -gnatg, which includes
7111 -- Warn_On_Obsolescent_ Feature). Once this issue
7112 -- is cleared in the sources, it can be enabled.
7114 elsif Warn_On_Obsolescent_Feature
and then False then
7116 ("applying 'Class to an untagged incomplete type"
7117 & " is an obsolescent feature (RM J.11)?r?", N
);
7121 Set_Is_Tagged_Type
(T
);
7122 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7123 Make_Class_Wide_Type
(T
);
7124 Set_Entity
(N
, Class_Wide_Type
(T
));
7125 Set_Etype
(N
, Class_Wide_Type
(T
));
7127 elsif Ekind
(T
) = E_Private_Type
7128 and then not Is_Generic_Type
(T
)
7129 and then In_Private_Part
(Scope
(T
))
7131 -- The Class attribute can be applied to an untagged private
7132 -- type fulfilled by a tagged type prior to the full type
7133 -- declaration (but only within the parent package's private
7134 -- part). Create the class-wide type now and check that the
7135 -- full type is tagged later during its analysis. Note that
7136 -- we do not mark the private type as tagged, unlike the
7137 -- case of incomplete types, because the type must still
7138 -- appear untagged to outside units.
7140 if No
(Class_Wide_Type
(T
)) then
7141 Make_Class_Wide_Type
(T
);
7144 Set_Entity
(N
, Class_Wide_Type
(T
));
7145 Set_Etype
(N
, Class_Wide_Type
(T
));
7148 -- Should we introduce a type Any_Tagged and use Wrong_Type
7149 -- here, it would be a bit more consistent???
7152 ("tagged type required, found}",
7153 Prefix
(N
), First_Subtype
(T
));
7154 Set_Entity
(N
, Any_Type
);
7158 -- Case of tagged type
7161 if Is_Concurrent_Type
(T
) then
7162 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7164 -- Previous error. Use current type, which at least
7165 -- provides some operations.
7167 C
:= Entity
(Prefix
(N
));
7170 C
:= Class_Wide_Type
7171 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7175 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7178 Set_Entity_With_Checks
(N
, C
);
7179 Generate_Reference
(C
, N
);
7183 -- Base attribute, not allowed in Ada 83
7185 elsif Attribute_Name
(N
) = Name_Base
then
7186 Error_Msg_Name_1
:= Name_Base
;
7187 Check_SPARK_05_Restriction
7188 ("attribute% is only allowed as prefix of another attribute", N
);
7190 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7192 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7195 Find_Type
(Prefix
(N
));
7196 Typ
:= Entity
(Prefix
(N
));
7198 if Ada_Version
>= Ada_95
7199 and then not Is_Scalar_Type
(Typ
)
7200 and then not Is_Generic_Type
(Typ
)
7203 ("prefix of Base attribute must be scalar type",
7206 elsif Warn_On_Redundant_Constructs
7207 and then Base_Type
(Typ
) = Typ
7209 Error_Msg_NE
-- CODEFIX
7210 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7213 T
:= Base_Type
(Typ
);
7215 -- Rewrite attribute reference with type itself (see similar
7216 -- processing in Analyze_Attribute, case Base). Preserve prefix
7217 -- if present, for other legality checks.
7219 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7221 Make_Expanded_Name
(Sloc
(N
),
7223 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7224 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7227 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7234 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7236 -- This is handled in Analyze_Attribute
7240 -- All other attributes are invalid in a subtype mark
7243 Error_Msg_N
("invalid attribute in subtype mark", N
);
7249 if Is_Entity_Name
(N
) then
7250 T_Name
:= Entity
(N
);
7252 Error_Msg_N
("subtype mark required in this context", N
);
7253 Set_Etype
(N
, Any_Type
);
7257 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7259 -- Undefined id. Make it into a valid type
7261 Set_Entity
(N
, Any_Type
);
7263 elsif not Is_Type
(T_Name
)
7264 and then T_Name
/= Standard_Void_Type
7266 Error_Msg_Sloc
:= Sloc
(T_Name
);
7267 Error_Msg_N
("subtype mark required in this context", N
);
7268 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7269 Set_Entity
(N
, Any_Type
);
7272 -- If the type is an incomplete type created to handle
7273 -- anonymous access components of a record type, then the
7274 -- incomplete type is the visible entity and subsequent
7275 -- references will point to it. Mark the original full
7276 -- type as referenced, to prevent spurious warnings.
7278 if Is_Incomplete_Type
(T_Name
)
7279 and then Present
(Full_View
(T_Name
))
7280 and then not Comes_From_Source
(T_Name
)
7282 Set_Referenced
(Full_View
(T_Name
));
7285 T_Name
:= Get_Full_View
(T_Name
);
7287 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7288 -- limited-with clauses
7290 if From_Limited_With
(T_Name
)
7291 and then Ekind
(T_Name
) in Incomplete_Kind
7292 and then Present
(Non_Limited_View
(T_Name
))
7293 and then Is_Interface
(Non_Limited_View
(T_Name
))
7295 T_Name
:= Non_Limited_View
(T_Name
);
7298 if In_Open_Scopes
(T_Name
) then
7299 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7301 -- In Ada 2005, a task name can be used in an access
7302 -- definition within its own body. It cannot be used
7303 -- in the discriminant part of the task declaration,
7304 -- nor anywhere else in the declaration because entries
7305 -- cannot have access parameters.
7307 if Ada_Version
>= Ada_2005
7308 and then Nkind
(Parent
(N
)) = N_Access_Definition
7310 Set_Entity
(N
, T_Name
);
7311 Set_Etype
(N
, T_Name
);
7313 if Has_Completion
(T_Name
) then
7318 ("task type cannot be used as type mark " &
7319 "within its own declaration", N
);
7324 ("task type cannot be used as type mark " &
7325 "within its own spec or body", N
);
7328 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7330 -- In Ada 2005, a protected name can be used in an access
7331 -- definition within its own body.
7333 if Ada_Version
>= Ada_2005
7334 and then Nkind
(Parent
(N
)) = N_Access_Definition
7336 Set_Entity
(N
, T_Name
);
7337 Set_Etype
(N
, T_Name
);
7342 ("protected type cannot be used as type mark " &
7343 "within its own spec or body", N
);
7347 Error_Msg_N
("type declaration cannot refer to itself", N
);
7350 Set_Etype
(N
, Any_Type
);
7351 Set_Entity
(N
, Any_Type
);
7352 Set_Error_Posted
(T_Name
);
7356 Set_Entity
(N
, T_Name
);
7357 Set_Etype
(N
, T_Name
);
7361 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7362 if Is_Fixed_Point_Type
(Etype
(N
)) then
7363 Check_Restriction
(No_Fixed_Point
, N
);
7364 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7365 Check_Restriction
(No_Floating_Point
, N
);
7368 -- A Ghost type must appear in a specific context
7370 if Is_Ghost_Entity
(Etype
(N
)) then
7371 Check_Ghost_Context
(Etype
(N
), N
);
7376 ------------------------------------
7377 -- Has_Implicit_Character_Literal --
7378 ------------------------------------
7380 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7382 Found
: Boolean := False;
7383 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7384 Priv_Id
: Entity_Id
:= Empty
;
7387 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7388 Priv_Id
:= First_Private_Entity
(P
);
7391 if P
= Standard_Standard
then
7392 Change_Selected_Component_To_Expanded_Name
(N
);
7393 Rewrite
(N
, Selector_Name
(N
));
7395 Set_Etype
(Original_Node
(N
), Standard_Character
);
7399 Id
:= First_Entity
(P
);
7400 while Present
(Id
) and then Id
/= Priv_Id
loop
7401 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7403 -- We replace the node with the literal itself, resolve as a
7404 -- character, and set the type correctly.
7407 Change_Selected_Component_To_Expanded_Name
(N
);
7408 Rewrite
(N
, Selector_Name
(N
));
7411 Set_Etype
(Original_Node
(N
), Id
);
7415 -- More than one type derived from Character in given scope.
7416 -- Collect all possible interpretations.
7418 Add_One_Interp
(N
, Id
, Id
);
7426 end Has_Implicit_Character_Literal
;
7428 ----------------------
7429 -- Has_Private_With --
7430 ----------------------
7432 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7433 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7437 Item
:= First
(Context_Items
(Comp_Unit
));
7438 while Present
(Item
) loop
7439 if Nkind
(Item
) = N_With_Clause
7440 and then Private_Present
(Item
)
7441 and then Entity
(Name
(Item
)) = E
7450 end Has_Private_With
;
7452 ---------------------------
7453 -- Has_Implicit_Operator --
7454 ---------------------------
7456 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7457 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7458 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7460 Priv_Id
: Entity_Id
:= Empty
;
7462 procedure Add_Implicit_Operator
7464 Op_Type
: Entity_Id
:= Empty
);
7465 -- Add implicit interpretation to node N, using the type for which a
7466 -- predefined operator exists. If the operator yields a boolean type,
7467 -- the Operand_Type is implicitly referenced by the operator, and a
7468 -- reference to it must be generated.
7470 ---------------------------
7471 -- Add_Implicit_Operator --
7472 ---------------------------
7474 procedure Add_Implicit_Operator
7476 Op_Type
: Entity_Id
:= Empty
)
7478 Predef_Op
: Entity_Id
;
7481 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7482 while Present
(Predef_Op
)
7483 and then Scope
(Predef_Op
) /= Standard_Standard
7485 Predef_Op
:= Homonym
(Predef_Op
);
7488 if Nkind
(N
) = N_Selected_Component
then
7489 Change_Selected_Component_To_Expanded_Name
(N
);
7492 -- If the context is an unanalyzed function call, determine whether
7493 -- a binary or unary interpretation is required.
7495 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7497 Is_Binary_Call
: constant Boolean :=
7499 (Next
(First
(Expressions
(Parent
(N
)))));
7500 Is_Binary_Op
: constant Boolean :=
7502 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7503 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7506 if Is_Binary_Call
then
7507 if Is_Binary_Op
then
7508 Add_One_Interp
(N
, Predef_Op
, T
);
7510 Add_One_Interp
(N
, Predef_Op2
, T
);
7514 if not Is_Binary_Op
then
7515 Add_One_Interp
(N
, Predef_Op
, T
);
7517 Add_One_Interp
(N
, Predef_Op2
, T
);
7523 Add_One_Interp
(N
, Predef_Op
, T
);
7525 -- For operators with unary and binary interpretations, if
7526 -- context is not a call, add both
7528 if Present
(Homonym
(Predef_Op
)) then
7529 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7533 -- The node is a reference to a predefined operator, and
7534 -- an implicit reference to the type of its operands.
7536 if Present
(Op_Type
) then
7537 Generate_Operator_Reference
(N
, Op_Type
);
7539 Generate_Operator_Reference
(N
, T
);
7541 end Add_Implicit_Operator
;
7543 -- Start of processing for Has_Implicit_Operator
7546 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7547 Priv_Id
:= First_Private_Entity
(P
);
7550 Id
:= First_Entity
(P
);
7554 -- Boolean operators: an implicit declaration exists if the scope
7555 -- contains a declaration for a derived Boolean type, or for an
7556 -- array of Boolean type.
7558 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7559 while Id
/= Priv_Id
loop
7560 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7561 Add_Implicit_Operator
(Id
);
7568 -- Equality: look for any non-limited type (result is Boolean)
7570 when Name_Op_Eq | Name_Op_Ne
=>
7571 while Id
/= Priv_Id
loop
7573 and then not Is_Limited_Type
(Id
)
7574 and then Is_Base_Type
(Id
)
7576 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7583 -- Comparison operators: scalar type, or array of scalar
7585 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7586 while Id
/= Priv_Id
loop
7587 if (Is_Scalar_Type
(Id
)
7588 or else (Is_Array_Type
(Id
)
7589 and then Is_Scalar_Type
(Component_Type
(Id
))))
7590 and then Is_Base_Type
(Id
)
7592 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7599 -- Arithmetic operators: any numeric type
7609 while Id
/= Priv_Id
loop
7610 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7611 Add_Implicit_Operator
(Id
);
7618 -- Concatenation: any one-dimensional array type
7620 when Name_Op_Concat
=>
7621 while Id
/= Priv_Id
loop
7622 if Is_Array_Type
(Id
)
7623 and then Number_Dimensions
(Id
) = 1
7624 and then Is_Base_Type
(Id
)
7626 Add_Implicit_Operator
(Id
);
7633 -- What is the others condition here? Should we be using a
7634 -- subtype of Name_Id that would restrict to operators ???
7636 when others => null;
7639 -- If we fall through, then we do not have an implicit operator
7643 end Has_Implicit_Operator
;
7645 -----------------------------------
7646 -- Has_Loop_In_Inner_Open_Scopes --
7647 -----------------------------------
7649 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7651 -- Several scope stacks are maintained by Scope_Stack. The base of the
7652 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7653 -- flag in the scope stack entry. Note that the scope stacks used to
7654 -- simply be delimited implicitly by the presence of Standard_Standard
7655 -- at their base, but there now are cases where this is not sufficient
7656 -- because Standard_Standard actually may appear in the middle of the
7657 -- active set of scopes.
7659 for J
in reverse 0 .. Scope_Stack
.Last
loop
7661 -- S was reached without seing a loop scope first
7663 if Scope_Stack
.Table
(J
).Entity
= S
then
7666 -- S was not yet reached, so it contains at least one inner loop
7668 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7672 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7673 -- cases where Standard_Standard appears in the middle of the active
7674 -- set of scopes. This affects the declaration and overriding of
7675 -- private inherited operations in instantiations of generic child
7678 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7681 raise Program_Error
; -- unreachable
7682 end Has_Loop_In_Inner_Open_Scopes
;
7684 --------------------
7685 -- In_Open_Scopes --
7686 --------------------
7688 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7690 -- Several scope stacks are maintained by Scope_Stack. The base of the
7691 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7692 -- flag in the scope stack entry. Note that the scope stacks used to
7693 -- simply be delimited implicitly by the presence of Standard_Standard
7694 -- at their base, but there now are cases where this is not sufficient
7695 -- because Standard_Standard actually may appear in the middle of the
7696 -- active set of scopes.
7698 for J
in reverse 0 .. Scope_Stack
.Last
loop
7699 if Scope_Stack
.Table
(J
).Entity
= S
then
7703 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7704 -- cases where Standard_Standard appears in the middle of the active
7705 -- set of scopes. This affects the declaration and overriding of
7706 -- private inherited operations in instantiations of generic child
7709 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7715 -----------------------------
7716 -- Inherit_Renamed_Profile --
7717 -----------------------------
7719 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7726 if Ekind
(Old_S
) = E_Operator
then
7727 New_F
:= First_Formal
(New_S
);
7729 while Present
(New_F
) loop
7730 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7731 Next_Formal
(New_F
);
7734 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7737 New_F
:= First_Formal
(New_S
);
7738 Old_F
:= First_Formal
(Old_S
);
7740 while Present
(New_F
) loop
7741 New_T
:= Etype
(New_F
);
7742 Old_T
:= Etype
(Old_F
);
7744 -- If the new type is a renaming of the old one, as is the
7745 -- case for actuals in instances, retain its name, to simplify
7746 -- later disambiguation.
7748 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7749 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7750 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7754 Set_Etype
(New_F
, Old_T
);
7757 Next_Formal
(New_F
);
7758 Next_Formal
(Old_F
);
7761 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7762 Set_Etype
(New_S
, Etype
(Old_S
));
7765 end Inherit_Renamed_Profile
;
7771 procedure Initialize
is
7776 -------------------------
7777 -- Install_Use_Clauses --
7778 -------------------------
7780 procedure Install_Use_Clauses
7782 Force_Installation
: Boolean := False)
7790 while Present
(U
) loop
7792 -- Case of USE package
7794 if Nkind
(U
) = N_Use_Package_Clause
then
7795 P
:= First
(Names
(U
));
7796 while Present
(P
) loop
7799 if Ekind
(Id
) = E_Package
then
7801 Note_Redundant_Use
(P
);
7803 elsif Present
(Renamed_Object
(Id
))
7804 and then In_Use
(Renamed_Object
(Id
))
7806 Note_Redundant_Use
(P
);
7808 elsif Force_Installation
or else Applicable_Use
(P
) then
7809 Use_One_Package
(Id
, U
);
7820 P
:= First
(Subtype_Marks
(U
));
7821 while Present
(P
) loop
7822 if not Is_Entity_Name
(P
)
7823 or else No
(Entity
(P
))
7827 elsif Entity
(P
) /= Any_Type
then
7835 Next_Use_Clause
(U
);
7837 end Install_Use_Clauses
;
7839 -------------------------------------
7840 -- Is_Appropriate_For_Entry_Prefix --
7841 -------------------------------------
7843 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7844 P_Type
: Entity_Id
:= T
;
7847 if Is_Access_Type
(P_Type
) then
7848 P_Type
:= Designated_Type
(P_Type
);
7851 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7852 end Is_Appropriate_For_Entry_Prefix
;
7854 -------------------------------
7855 -- Is_Appropriate_For_Record --
7856 -------------------------------
7858 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7860 function Has_Components
(T1
: Entity_Id
) return Boolean;
7861 -- Determine if given type has components (i.e. is either a record
7862 -- type or a type that has discriminants).
7864 --------------------
7865 -- Has_Components --
7866 --------------------
7868 function Has_Components
(T1
: Entity_Id
) return Boolean is
7870 return Is_Record_Type
(T1
)
7871 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7872 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7873 or else (Is_Incomplete_Type
(T1
)
7874 and then From_Limited_With
(T1
)
7875 and then Present
(Non_Limited_View
(T1
))
7876 and then Is_Record_Type
7877 (Get_Full_View
(Non_Limited_View
(T1
))));
7880 -- Start of processing for Is_Appropriate_For_Record
7885 and then (Has_Components
(T
)
7886 or else (Is_Access_Type
(T
)
7887 and then Has_Components
(Designated_Type
(T
))));
7888 end Is_Appropriate_For_Record
;
7890 ------------------------
7891 -- Note_Redundant_Use --
7892 ------------------------
7894 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7895 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7896 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7897 Decl
: constant Node_Id
:= Parent
(Clause
);
7899 Prev_Use
: Node_Id
:= Empty
;
7900 Redundant
: Node_Id
:= Empty
;
7901 -- The Use_Clause which is actually redundant. In the simplest case it
7902 -- is Pack itself, but when we compile a body we install its context
7903 -- before that of its spec, in which case it is the use_clause in the
7904 -- spec that will appear to be redundant, and we want the warning to be
7905 -- placed on the body. Similar complications appear when the redundancy
7906 -- is between a child unit and one of its ancestors.
7909 Set_Redundant_Use
(Clause
, True);
7911 if not Comes_From_Source
(Clause
)
7913 or else not Warn_On_Redundant_Constructs
7918 if not Is_Compilation_Unit
(Current_Scope
) then
7920 -- If the use_clause is in an inner scope, it is made redundant by
7921 -- some clause in the current context, with one exception: If we're
7922 -- compiling a nested package body, and the use_clause comes from the
7923 -- corresponding spec, the clause is not necessarily fully redundant,
7924 -- so we should not warn. If a warning was warranted, it would have
7925 -- been given when the spec was processed.
7927 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7929 Package_Spec_Entity
: constant Entity_Id
:=
7930 Defining_Unit_Name
(Parent
(Decl
));
7932 if In_Package_Body
(Package_Spec_Entity
) then
7938 Redundant
:= Clause
;
7939 Prev_Use
:= Cur_Use
;
7941 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7943 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7944 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7948 if Cur_Unit
= New_Unit
then
7950 -- Redundant clause in same body
7952 Redundant
:= Clause
;
7953 Prev_Use
:= Cur_Use
;
7955 elsif Cur_Unit
= Current_Sem_Unit
then
7957 -- If the new clause is not in the current unit it has been
7958 -- analyzed first, and it makes the other one redundant.
7959 -- However, if the new clause appears in a subunit, Cur_Unit
7960 -- is still the parent, and in that case the redundant one
7961 -- is the one appearing in the subunit.
7963 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7964 Redundant
:= Clause
;
7965 Prev_Use
:= Cur_Use
;
7967 -- Most common case: redundant clause in body,
7968 -- original clause in spec. Current scope is spec entity.
7973 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7975 Redundant
:= Cur_Use
;
7979 -- The new clause may appear in an unrelated unit, when
7980 -- the parents of a generic are being installed prior to
7981 -- instantiation. In this case there must be no warning.
7982 -- We detect this case by checking whether the current top
7983 -- of the stack is related to the current compilation.
7985 Scop
:= Current_Scope
;
7986 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7987 if Is_Compilation_Unit
(Scop
)
7988 and then not Is_Child_Unit
(Scop
)
7992 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7996 Scop
:= Scope
(Scop
);
7999 Redundant
:= Cur_Use
;
8003 elsif New_Unit
= Current_Sem_Unit
then
8004 Redundant
:= Clause
;
8005 Prev_Use
:= Cur_Use
;
8008 -- Neither is the current unit, so they appear in parent or
8009 -- sibling units. Warning will be emitted elsewhere.
8015 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
8016 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
8018 -- Use_clause is in child unit of current unit, and the child unit
8019 -- appears in the context of the body of the parent, so it has been
8020 -- installed first, even though it is the redundant one. Depending on
8021 -- their placement in the context, the visible or the private parts
8022 -- of the two units, either might appear as redundant, but the
8023 -- message has to be on the current unit.
8025 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
8026 Redundant
:= Cur_Use
;
8029 Redundant
:= Clause
;
8030 Prev_Use
:= Cur_Use
;
8033 -- If the new use clause appears in the private part of a parent unit
8034 -- it may appear to be redundant w.r.t. a use clause in a child unit,
8035 -- but the previous use clause was needed in the visible part of the
8036 -- child, and no warning should be emitted.
8038 if Nkind
(Parent
(Decl
)) = N_Package_Specification
8040 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
8043 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
8044 Spec
: constant Node_Id
:=
8045 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
8048 if Is_Compilation_Unit
(Par
)
8049 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
8050 and then Parent
(Cur_Use
) = Spec
8052 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
8059 -- Finally, if the current use clause is in the context then
8060 -- the clause is redundant when it is nested within the unit.
8062 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
8063 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
8064 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
8066 Redundant
:= Clause
;
8067 Prev_Use
:= Cur_Use
;
8073 if Present
(Redundant
) then
8074 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
8075 Error_Msg_NE
-- CODEFIX
8076 ("& is already use-visible through previous use clause #??",
8077 Redundant
, Pack_Name
);
8079 end Note_Redundant_Use
;
8085 procedure Pop_Scope
is
8086 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8087 S
: constant Entity_Id
:= SST
.Entity
;
8090 if Debug_Flag_E
then
8094 -- Set Default_Storage_Pool field of the library unit if necessary
8096 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8098 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8101 Aux
: constant Node_Id
:=
8102 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8104 if No
(Default_Storage_Pool
(Aux
)) then
8105 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8110 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8111 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8112 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8113 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8114 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8115 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8116 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8117 Default_SSO
:= SST
.Save_Default_SSO
;
8118 Uneval_Old
:= SST
.Save_Uneval_Old
;
8120 if Debug_Flag_W
then
8121 Write_Str
("<-- exiting scope: ");
8122 Write_Name
(Chars
(Current_Scope
));
8123 Write_Str
(", Depth=");
8124 Write_Int
(Int
(Scope_Stack
.Last
));
8128 End_Use_Clauses
(SST
.First_Use_Clause
);
8130 -- If the actions to be wrapped are still there they will get lost
8131 -- causing incomplete code to be generated. It is better to abort in
8132 -- this case (and we do the abort even with assertions off since the
8133 -- penalty is incorrect code generation).
8135 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8136 raise Program_Error;
8139 -- Free last subprogram name if allocated, and pop scope
8141 Free (SST.Last_Subprogram_Name);
8142 Scope_Stack.Decrement_Last;
8149 procedure Push_Scope (S : Entity_Id) is
8150 E : constant Entity_Id := Scope (S);
8153 if Ekind (S) = E_Void then
8156 -- Set scope depth if not a non-concurrent type, and we have not yet set
8157 -- the scope depth. This means that we have the first occurrence of the
8158 -- scope, and this is where the depth is set.
8160 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8161 and then not Scope_Depth_Set (S)
8163 if S = Standard_Standard then
8164 Set_Scope_Depth_Value (S, Uint_0);
8166 elsif Is_Child_Unit (S) then
8167 Set_Scope_Depth_Value (S, Uint_1);
8169 elsif not Is_Record_Type (Current_Scope) then
8170 if Ekind (S) = E_Loop then
8171 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8173 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8178 Scope_Stack.Increment_Last;
8181 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8185 SST.Save_Scope_Suppress := Scope_Suppress;
8186 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8187 SST.Save_Check_Policy_List := Check_Policy_List;
8188 SST.Save_Default_Storage_Pool := Default_Pool;
8189 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8190 SST.Save_SPARK_Mode := SPARK_Mode;
8191 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8192 SST.Save_Default_SSO := Default_SSO;
8193 SST.Save_Uneval_Old := Uneval_Old;
8195 if Scope_Stack.Last > Scope_Stack.First then
8196 SST.Component_Alignment_Default := Scope_Stack.Table
8197 (Scope_Stack.Last - 1).
8198 Component_Alignment_Default;
8201 SST.Last_Subprogram_Name := null;
8202 SST.Is_Transient := False;
8203 SST.Node_To_Be_Wrapped := Empty;
8204 SST.Pending_Freeze_Actions := No_List;
8205 SST.Actions_To_Be_Wrapped := (others => No_List);
8206 SST.First_Use_Clause := Empty;
8207 SST.Is_Active_Stack_Base := False;
8208 SST.Previous_Visibility := False;
8209 SST.Locked_Shared_Objects := No_Elist;
8212 if Debug_Flag_W then
8213 Write_Str ("--> new scope: ");
8214 Write_Name (Chars (Current_Scope));
8215 Write_Str (", Id=");
8216 Write_Int (Int (Current_Scope));
8217 Write_Str (", Depth=");
8218 Write_Int (Int (Scope_Stack.Last));
8222 -- Deal with copying flags from the previous scope to this one. This is
8223 -- not necessary if either scope is standard, or if the new scope is a
8226 if S /= Standard_Standard
8227 and then Scope (S) /= Standard_Standard
8228 and then not Is_Child_Unit (S)
8230 if Nkind (E) not in N_Entity then
8234 -- Copy categorization flags from Scope (S) to S, this is not done
8235 -- when Scope (S) is Standard_Standard since propagation is from
8236 -- library unit entity inwards. Copy other relevant attributes as
8237 -- well (Discard_Names in particular).
8239 -- We only propagate inwards for library level entities,
8240 -- inner level subprograms do not inherit the categorization.
8242 if Is_Library_Level_Entity (S) then
8243 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8244 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8245 Set_Discard_Names (S, Discard_Names (E));
8246 Set_Suppress_Value_Tracking_On_Call
8247 (S, Suppress_Value_Tracking_On_Call (E));
8248 Set_Categorization_From_Scope (E => S, Scop => E);
8252 if Is_Child_Unit (S)
8253 and then Present (E)
8254 and then Ekind_In (E, E_Package, E_Generic_Package)
8256 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8259 Aux : constant Node_Id :=
8260 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8262 if Present (Default_Storage_Pool (Aux)) then
8263 Default_Pool := Default_Storage_Pool (Aux);
8269 ---------------------
8270 -- Premature_Usage --
8271 ---------------------
8273 procedure Premature_Usage (N : Node_Id) is
8274 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8275 E : Entity_Id := Entity (N);
8278 -- Within an instance, the analysis of the actual for a formal object
8279 -- does not see the name of the object itself. This is significant only
8280 -- if the object is an aggregate, where its analysis does not do any
8281 -- name resolution on component associations. (see 4717-008). In such a
8282 -- case, look for the visible homonym on the chain.
8284 if In_Instance and then Present (Homonym (E)) then
8286 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8292 Set_Etype (N, Etype (E));
8297 if Kind = N_Component_Declaration then
8299 ("component&! cannot be used before end of record declaration", N);
8301 elsif Kind = N_Parameter_Specification then
8303 ("formal parameter&! cannot be used before end of specification",
8306 elsif Kind = N_Discriminant_Specification then
8308 ("discriminant&! cannot be used before end of discriminant part",
8311 elsif Kind = N_Procedure_Specification
8312 or else Kind = N_Function_Specification
8315 ("subprogram&! cannot be used before end of its declaration",
8318 elsif Kind = N_Full_Type_Declaration then
8320 ("type& cannot be used before end of its declaration!", N);
8324 ("object& cannot be used before end of its declaration!", N);
8326 end Premature_Usage;
8328 ------------------------
8329 -- Present_System_Aux --
8330 ------------------------
8332 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8334 Aux_Name : Unit_Name_Type;
8335 Unum : Unit_Number_Type;
8340 function Find_System (C_Unit : Node_Id) return Entity_Id;
8341 -- Scan context clause of compilation unit to find with_clause
8348 function Find_System (C_Unit : Node_Id) return Entity_Id is
8349 With_Clause : Node_Id;
8352 With_Clause := First (Context_Items (C_Unit));
8353 while Present (With_Clause) loop
8354 if (Nkind (With_Clause) = N_With_Clause
8355 and then Chars (Name (With_Clause)) = Name_System)
8356 and then Comes_From_Source (With_Clause)
8367 -- Start of processing for Present_System_Aux
8370 -- The child unit may have been loaded and analyzed already
8372 if Present (System_Aux_Id) then
8375 -- If no previous pragma for System.Aux, nothing to load
8377 elsif No (System_Extend_Unit) then
8380 -- Use the unit name given in the pragma to retrieve the unit.
8381 -- Verify that System itself appears in the context clause of the
8382 -- current compilation. If System is not present, an error will
8383 -- have been reported already.
8386 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8388 The_Unit := Unit (Cunit (Current_Sem_Unit));
8392 (Nkind (The_Unit) = N_Package_Body
8393 or else (Nkind (The_Unit) = N_Subprogram_Body
8394 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8396 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8399 if No (With_Sys) and then Present (N) then
8401 -- If we are compiling a subunit, we need to examine its
8402 -- context as well (Current_Sem_Unit is the parent unit);
8404 The_Unit := Parent (N);
8405 while Nkind (The_Unit) /= N_Compilation_Unit loop
8406 The_Unit := Parent (The_Unit);
8409 if Nkind (Unit (The_Unit)) = N_Subunit then
8410 With_Sys := Find_System (The_Unit);
8414 if No (With_Sys) then
8418 Loc := Sloc (With_Sys);
8419 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8420 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8421 Name_Buffer (1 .. 7) := "system.";
8422 Name_Buffer (Name_Len + 8) := '%';
8423 Name_Buffer (Name_Len + 9) := 's
';
8424 Name_Len := Name_Len + 9;
8425 Aux_Name := Name_Find;
8429 (Load_Name => Aux_Name,
8432 Error_Node => With_Sys);
8434 if Unum /= No_Unit then
8435 Semantics (Cunit (Unum));
8437 Defining_Entity (Specification (Unit (Cunit (Unum))));
8440 Make_With_Clause (Loc,
8442 Make_Expanded_Name (Loc,
8443 Chars => Chars (System_Aux_Id),
8444 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8445 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8447 Set_Entity (Name (Withn), System_Aux_Id);
8449 Set_Library_Unit (Withn, Cunit (Unum));
8450 Set_Corresponding_Spec (Withn, System_Aux_Id);
8451 Set_First_Name (Withn, True);
8452 Set_Implicit_With (Withn, True);
8454 Insert_After (With_Sys, Withn);
8455 Mark_Rewrite_Insertion (Withn);
8456 Set_Context_Installed (Withn);
8460 -- Here if unit load failed
8463 Error_Msg_Name_1 := Name_System;
8464 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8466 ("extension package `%.%` does not exist",
8467 Opt.System_Extend_Unit);
8471 end Present_System_Aux;
8473 -------------------------
8474 -- Restore_Scope_Stack --
8475 -------------------------
8477 procedure Restore_Scope_Stack
8479 Handle_Use : Boolean := True)
8481 SS_Last : constant Int := Scope_Stack.Last;
8485 -- Restore visibility of previous scope stack, if any, using the list
8486 -- we saved (we use Remove, since this list will not be used again).
8489 Elmt := Last_Elmt (List);
8490 exit when Elmt = No_Elmt;
8491 Set_Is_Immediately_Visible (Node (Elmt));
8492 Remove_Last_Elmt (List);
8495 -- Restore use clauses
8497 if SS_Last >= Scope_Stack.First
8498 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8501 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8503 end Restore_Scope_Stack;
8505 ----------------------
8506 -- Save_Scope_Stack --
8507 ----------------------
8509 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8510 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8511 -- from immediate visibility entities and Restore_Scope_Stack took care
8512 -- of restoring their visibility analyzing the context of each entity. The
8513 -- problem of such approach is that it was fragile and caused unexpected
8514 -- visibility problems, and indeed one test was found where there was a
8517 -- Furthermore, the following experiment was carried out:
8519 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8520 -- entities whose attribute Is_Immediately_Visible is modified
8521 -- from True to False.
8523 -- - Restore_Scope_Stack was modified to store in another Elist2
8524 -- all the entities whose attribute Is_Immediately_Visible is
8525 -- modified from False to True.
8527 -- - Extra code was added to verify that all the elements of Elist1
8528 -- are found in Elist2
8530 -- This test shows that there may be more occurrences of this problem which
8531 -- have not yet been detected. As a result, we replaced that approach by
8532 -- the current one in which Save_Scope_Stack returns the list of entities
8533 -- whose visibility is changed, and that list is passed to Restore_Scope_
8534 -- Stack to undo that change. This approach is simpler and safer, although
8535 -- it consumes more memory.
8537 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8538 Result : constant Elist_Id := New_Elmt_List;
8541 SS_Last : constant Int := Scope_Stack.Last;
8543 procedure Remove_From_Visibility (E : Entity_Id);
8544 -- If E is immediately visible then append it to the result and remove
8545 -- it temporarily from visibility.
8547 ----------------------------
8548 -- Remove_From_Visibility --
8549 ----------------------------
8551 procedure Remove_From_Visibility (E : Entity_Id) is
8553 if Is_Immediately_Visible (E) then
8554 Append_Elmt (E, Result);
8555 Set_Is_Immediately_Visible (E, False);
8557 end Remove_From_Visibility;
8559 -- Start of processing for Save_Scope_Stack
8562 if SS_Last >= Scope_Stack.First
8563 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8566 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8569 -- If the call is from within a compilation unit, as when called from
8570 -- Rtsfind, make current entries in scope stack invisible while we
8571 -- analyze the new unit.
8573 for J in reverse 0 .. SS_Last loop
8574 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8575 or else No (Scope_Stack.Table (J).Entity);
8577 S := Scope_Stack.Table (J).Entity;
8579 Remove_From_Visibility (S);
8581 E := First_Entity (S);
8582 while Present (E) loop
8583 Remove_From_Visibility (E);
8591 end Save_Scope_Stack;
8597 procedure Set_Use (L : List_Id) is
8599 Pack_Name : Node_Id;
8606 while Present (Decl) loop
8607 if Nkind (Decl) = N_Use_Package_Clause then
8608 Chain_Use_Clause (Decl);
8610 Pack_Name := First (Names (Decl));
8611 while Present (Pack_Name) loop
8612 Pack := Entity (Pack_Name);
8614 if Ekind (Pack) = E_Package
8615 and then Applicable_Use (Pack_Name)
8617 Use_One_Package (Pack, Decl);
8623 elsif Nkind (Decl) = N_Use_Type_Clause then
8624 Chain_Use_Clause (Decl);
8626 Id := First (Subtype_Marks (Decl));
8627 while Present (Id) loop
8628 if Entity (Id) /= Any_Type then
8641 ---------------------
8642 -- Use_One_Package --
8643 ---------------------
8645 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8648 Current_Instance : Entity_Id := Empty;
8650 Private_With_OK : Boolean := False;
8653 if Ekind (P) /= E_Package then
8658 Set_Current_Use_Clause (P, N);
8660 -- Ada 2005 (AI-50217): Check restriction
8662 if From_Limited_With (P) then
8663 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8666 -- Find enclosing instance, if any
8669 Current_Instance := Current_Scope;
8670 while not Is_Generic_Instance (Current_Instance) loop
8671 Current_Instance := Scope (Current_Instance);
8674 if No (Hidden_By_Use_Clause (N)) then
8675 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8679 -- If unit is a package renaming, indicate that the renamed
8680 -- package is also in use (the flags on both entities must
8681 -- remain consistent, and a subsequent use of either of them
8682 -- should be recognized as redundant).
8684 if Present (Renamed_Object (P)) then
8685 Set_In_Use (Renamed_Object (P));
8686 Set_Current_Use_Clause (Renamed_Object (P), N);
8687 Real_P := Renamed_Object (P);
8692 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8693 -- found in the private part of a package specification
8695 if In_Private_Part (Current_Scope)
8696 and then Has_Private_With (P)
8697 and then Is_Child_Unit (Current_Scope)
8698 and then Is_Child_Unit (P)
8699 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8701 Private_With_OK := True;
8704 -- Loop through entities in one package making them potentially
8707 Id := First_Entity (P);
8709 and then (Id /= First_Private_Entity (P)
8710 or else Private_With_OK) -- Ada 2005 (AI-262)
8712 Prev := Current_Entity (Id);
8713 while Present (Prev) loop
8714 if Is_Immediately_Visible (Prev)
8715 and then (not Is_Overloadable (Prev)
8716 or else not Is_Overloadable (Id)
8717 or else (Type_Conformant (Id, Prev)))
8719 if No (Current_Instance) then
8721 -- Potentially use-visible entity remains hidden
8723 goto Next_Usable_Entity;
8725 -- A use clause within an instance hides outer global entities,
8726 -- which are not used to resolve local entities in the
8727 -- instance. Note that the predefined entities in Standard
8728 -- could not have been hidden in the generic by a use clause,
8729 -- and therefore remain visible. Other compilation units whose
8730 -- entities appear in Standard must be hidden in an instance.
8732 -- To determine whether an entity is external to the instance
8733 -- we compare the scope depth of its scope with that of the
8734 -- current instance. However, a generic actual of a subprogram
8735 -- instance is declared in the wrapper package but will not be
8736 -- hidden by a use-visible entity. similarly, an entity that is
8737 -- declared in an enclosing instance will not be hidden by an
8738 -- an entity declared in a generic actual, which can only have
8739 -- been use-visible in the generic and will not have hidden the
8740 -- entity in the generic parent.
8742 -- If Id is called Standard, the predefined package with the
8743 -- same name is in the homonym chain. It has to be ignored
8744 -- because it has no defined scope (being the only entity in
8745 -- the system with this mandated behavior).
8747 elsif not Is_Hidden (Id)
8748 and then Present (Scope (Prev))
8749 and then not Is_Wrapper_Package (Scope (Prev))
8750 and then Scope_Depth (Scope (Prev)) <
8751 Scope_Depth (Current_Instance)
8752 and then (Scope (Prev) /= Standard_Standard
8753 or else Sloc (Prev) > Standard_Location)
8755 if In_Open_Scopes (Scope (Prev))
8756 and then Is_Generic_Instance (Scope (Prev))
8757 and then Present (Associated_Formal_Package (P))
8762 Set_Is_Potentially_Use_Visible (Id);
8763 Set_Is_Immediately_Visible (Prev, False);
8764 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8768 -- A user-defined operator is not use-visible if the predefined
8769 -- operator for the type is immediately visible, which is the case
8770 -- if the type of the operand is in an open scope. This does not
8771 -- apply to user-defined operators that have operands of different
8772 -- types, because the predefined mixed mode operations (multiply
8773 -- and divide) apply to universal types and do not hide anything.
8775 elsif Ekind (Prev) = E_Operator
8776 and then Operator_Matches_Spec (Prev, Id)
8777 and then In_Open_Scopes
8778 (Scope (Base_Type (Etype (First_Formal (Id)))))
8779 and then (No (Next_Formal (First_Formal (Id)))
8780 or else Etype (First_Formal (Id)) =
8781 Etype (Next_Formal (First_Formal (Id)))
8782 or else Chars (Prev) = Name_Op_Expon)
8784 goto Next_Usable_Entity;
8786 -- In an instance, two homonyms may become use_visible through the
8787 -- actuals of distinct formal packages. In the generic, only the
8788 -- current one would have been visible, so make the other one
8791 elsif Present (Current_Instance)
8792 and then Is_Potentially_Use_Visible (Prev)
8793 and then not Is_Overloadable (Prev)
8794 and then Scope (Id) /= Scope (Prev)
8795 and then Used_As_Generic_Actual (Scope (Prev))
8796 and then Used_As_Generic_Actual (Scope (Id))
8797 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8798 Current_Use_Clause (Scope (Id)))
8800 Set_Is_Potentially_Use_Visible (Prev, False);
8801 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8804 Prev := Homonym (Prev);
8807 -- On exit, we know entity is not hidden, unless it is private
8809 if not Is_Hidden (Id)
8810 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8812 Set_Is_Potentially_Use_Visible (Id);
8814 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8815 Set_Is_Potentially_Use_Visible (Full_View (Id));
8819 <<Next_Usable_Entity>>
8823 -- Child units are also made use-visible by a use clause, but they may
8824 -- appear after all visible declarations in the parent entity list.
8826 while Present (Id) loop
8827 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8828 Set_Is_Potentially_Use_Visible (Id);
8834 if Chars (Real_P) = Name_System
8835 and then Scope (Real_P) = Standard_Standard
8836 and then Present_System_Aux (N)
8838 Use_One_Package (System_Aux_Id, N);
8841 end Use_One_Package;
8847 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8849 Is_Known_Used : Boolean;
8853 function Spec_Reloaded_For_Body return Boolean;
8854 -- Determine whether the compilation unit is a package body and the use
8855 -- type clause is in the spec of the same package. Even though the spec
8856 -- was analyzed first, its context is reloaded when analysing the body.
8858 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8859 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8860 -- class-wide operations of ancestor types are use-visible if the
8861 -- ancestor type is visible.
8863 ----------------------------
8864 -- Spec_Reloaded_For_Body --
8865 ----------------------------
8867 function Spec_Reloaded_For_Body return Boolean is
8869 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8871 Spec : constant Node_Id :=
8872 Parent (List_Containing (Parent (Id)));
8875 -- Check whether type is declared in a package specification,
8876 -- and current unit is the corresponding package body. The
8877 -- use clauses themselves may be within a nested package.
8880 Nkind (Spec) = N_Package_Specification
8882 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8883 Cunit_Entity (Current_Sem_Unit));
8888 end Spec_Reloaded_For_Body;
8890 -------------------------------
8891 -- Use_Class_Wide_Operations --
8892 -------------------------------
8894 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8898 function Is_Class_Wide_Operation_Of
8900 T : Entity_Id) return Boolean;
8901 -- Determine whether a subprogram has a class-wide parameter or
8902 -- result that is T'Class.
8904 ---------------------------------
8905 -- Is_Class_Wide_Operation_Of --
8906 ---------------------------------
8908 function Is_Class_Wide_Operation_Of
8910 T : Entity_Id) return Boolean
8915 Formal := First_Formal (Op);
8916 while Present (Formal) loop
8917 if Etype (Formal) = Class_Wide_Type (T) then
8920 Next_Formal (Formal);
8923 if Etype (Op) = Class_Wide_Type (T) then
8928 end Is_Class_Wide_Operation_Of;
8930 -- Start of processing for Use_Class_Wide_Operations
8933 Scop := Scope (Typ);
8934 if not Is_Hidden (Scop) then
8935 Ent := First_Entity (Scop);
8936 while Present (Ent) loop
8937 if Is_Overloadable (Ent)
8938 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8939 and then not Is_Potentially_Use_Visible (Ent)
8941 Set_Is_Potentially_Use_Visible (Ent);
8942 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8949 if Is_Derived_Type (Typ) then
8950 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8952 end Use_Class_Wide_Operations;
8954 -- Start of processing for Use_One_Type
8957 -- It is the type determined by the subtype mark (8.4(8)) whose
8958 -- operations become potentially use-visible.
8960 T := Base_Type (Entity (Id));
8962 -- Either the type itself is used, the package where it is declared
8963 -- is in use or the entity is declared in the current package, thus
8968 or else In_Use (Scope (T))
8969 or else Scope (T) = Current_Scope;
8971 Set_Redundant_Use (Id,
8972 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8974 if Ekind (T) = E_Incomplete_Type then
8975 Error_Msg_N ("premature usage of incomplete type", Id);
8977 elsif In_Open_Scopes (Scope (T)) then
8980 -- A limited view cannot appear in a use_type clause. However, an access
8981 -- type whose designated type is limited has the flag but is not itself
8982 -- a limited view unless we only have a limited view of its enclosing
8985 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8987 ("incomplete type from limited view "
8988 & "cannot appear in use clause", Id);
8990 -- If the subtype mark designates a subtype in a different package,
8991 -- we have to check that the parent type is visible, otherwise the
8992 -- use type clause is a noop. Not clear how to do that???
8994 elsif not Redundant_Use (Id) then
8997 -- If T is tagged, primitive operators on class-wide operands
8998 -- are also available.
9000 if Is_Tagged_Type (T) then
9001 Set_In_Use (Class_Wide_Type (T));
9004 Set_Current_Use_Clause (T, Parent (Id));
9006 -- Iterate over primitive operations of the type. If an operation is
9007 -- already use_visible, it is the result of a previous use_clause,
9008 -- and already appears on the corresponding entity chain. If the
9009 -- clause is being reinstalled, operations are already use-visible.
9015 Op_List := Collect_Primitive_Operations (T);
9016 Elmt := First_Elmt (Op_List);
9017 while Present (Elmt) loop
9018 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
9019 or else Chars (Node (Elmt)) in Any_Operator_Name)
9020 and then not Is_Hidden (Node (Elmt))
9021 and then not Is_Potentially_Use_Visible (Node (Elmt))
9023 Set_Is_Potentially_Use_Visible (Node (Elmt));
9024 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9026 elsif Ada_Version >= Ada_2012
9027 and then All_Present (Parent (Id))
9028 and then not Is_Hidden (Node (Elmt))
9029 and then not Is_Potentially_Use_Visible (Node (Elmt))
9031 Set_Is_Potentially_Use_Visible (Node (Elmt));
9032 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9039 if Ada_Version >= Ada_2012
9040 and then All_Present (Parent (Id))
9041 and then Is_Tagged_Type (T)
9043 Use_Class_Wide_Operations (T);
9047 -- If warning on redundant constructs, check for unnecessary WITH
9049 if Warn_On_Redundant_Constructs
9050 and then Is_Known_Used
9052 -- with P; with P; use P;
9053 -- package P is package X is package body X is
9054 -- type T ... use P.T;
9056 -- The compilation unit is the body of X. GNAT first compiles the
9057 -- spec of X, then proceeds to the body. At that point P is marked
9058 -- as use visible. The analysis then reinstalls the spec along with
9059 -- its context. The use clause P.T is now recognized as redundant,
9060 -- but in the wrong context. Do not emit a warning in such cases.
9061 -- Do not emit a warning either if we are in an instance, there is
9062 -- no redundancy between an outer use_clause and one that appears
9063 -- within the generic.
9065 and then not Spec_Reloaded_For_Body
9066 and then not In_Instance
9068 -- The type already has a use clause
9072 -- Case where we know the current use clause for the type
9074 if Present (Current_Use_Clause (T)) then
9075 Use_Clause_Known : declare
9076 Clause1 : constant Node_Id := Parent (Id);
9077 Clause2 : constant Node_Id := Current_Use_Clause (T);
9084 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9085 -- Return the appropriate entity for determining which unit
9086 -- has a deeper scope: the defining entity for U, unless U
9087 -- is a package instance, in which case we retrieve the
9088 -- entity of the instance spec.
9090 --------------------
9091 -- Entity_Of_Unit --
9092 --------------------
9094 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9096 if Nkind (U) = N_Package_Instantiation
9097 and then Analyzed (U)
9099 return Defining_Entity (Instance_Spec (U));
9101 return Defining_Entity (U);
9105 -- Start of processing for Use_Clause_Known
9108 -- If both current use type clause and the use type clause
9109 -- for the type are at the compilation unit level, one of
9110 -- the units must be an ancestor of the other, and the
9111 -- warning belongs on the descendant.
9113 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9115 Nkind (Parent (Clause2)) = N_Compilation_Unit
9117 -- If the unit is a subprogram body that acts as spec,
9118 -- the context clause is shared with the constructed
9119 -- subprogram spec. Clearly there is no redundancy.
9121 if Clause1 = Clause2 then
9125 Unit1 := Unit (Parent (Clause1));
9126 Unit2 := Unit (Parent (Clause2));
9128 -- If both clauses are on same unit, or one is the body
9129 -- of the other, or one of them is in a subunit, report
9130 -- redundancy on the later one.
9132 if Unit1 = Unit2 then
9133 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9134 Error_Msg_NE -- CODEFIX
9135 ("& is already use-visible through previous "
9136 & "use_type_clause #??", Clause1, T);
9139 elsif Nkind (Unit1) = N_Subunit then
9140 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9141 Error_Msg_NE -- CODEFIX
9142 ("& is already use-visible through previous "
9143 & "use_type_clause #??", Clause1, T);
9146 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9147 and then Nkind (Unit1) /= Nkind (Unit2)
9148 and then Nkind (Unit1) /= N_Subunit
9150 Error_Msg_Sloc := Sloc (Clause1);
9151 Error_Msg_NE -- CODEFIX
9152 ("& is already use-visible through previous "
9153 & "use_type_clause #??", Current_Use_Clause (T), T);
9157 -- There is a redundant use type clause in a child unit.
9158 -- Determine which of the units is more deeply nested.
9159 -- If a unit is a package instance, retrieve the entity
9160 -- and its scope from the instance spec.
9162 Ent1 := Entity_Of_Unit (Unit1);
9163 Ent2 := Entity_Of_Unit (Unit2);
9165 if Scope (Ent2) = Standard_Standard then
9166 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9169 elsif Scope (Ent1) = Standard_Standard then
9170 Error_Msg_Sloc := Sloc (Id);
9173 -- If both units are child units, we determine which one
9174 -- is the descendant by the scope distance to the
9175 -- ultimate parent unit.
9185 and then Present (S2)
9186 and then S1 /= Standard_Standard
9187 and then S2 /= Standard_Standard
9193 if S1 = Standard_Standard then
9194 Error_Msg_Sloc := Sloc (Id);
9197 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9203 Error_Msg_NE -- CODEFIX
9204 ("& is already use-visible through previous "
9205 & "use_type_clause #??", Err_No, Id);
9207 -- Case where current use type clause and the use type
9208 -- clause for the type are not both at the compilation unit
9209 -- level. In this case we don't have location information.
9212 Error_Msg_NE -- CODEFIX
9213 ("& is already use-visible through previous "
9214 & "use type clause??", Id, T);
9216 end Use_Clause_Known;
9218 -- Here if Current_Use_Clause is not set for T, another case
9219 -- where we do not have the location information available.
9222 Error_Msg_NE -- CODEFIX
9223 ("& is already use-visible through previous "
9224 & "use type clause??", Id, T);
9227 -- The package where T is declared is already used
9229 elsif In_Use (Scope (T)) then
9230 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9231 Error_Msg_NE -- CODEFIX
9232 ("& is already use-visible through package use clause #??",
9235 -- The current scope is the package where T is declared
9238 Error_Msg_Node_2 := Scope (T);
9239 Error_Msg_NE -- CODEFIX
9240 ("& is already use-visible inside package &??", Id, T);
9249 procedure Write_Info is
9250 Id : Entity_Id := First_Entity (Current_Scope);
9253 -- No point in dumping standard entities
9255 if Current_Scope = Standard_Standard then
9259 Write_Str ("========================================================");
9261 Write_Str (" Defined Entities in ");
9262 Write_Name (Chars (Current_Scope));
9264 Write_Str ("========================================================");
9268 Write_Str ("-- none --");
9272 while Present (Id) loop
9273 Write_Entity_Info (Id, " ");
9278 if Scope (Current_Scope) = Standard_Standard then
9280 -- Print information on the current unit itself
9282 Write_Entity_Info (Current_Scope, " ");
9295 for J in reverse 1 .. Scope_Stack.Last loop
9296 S := Scope_Stack.Table (J).Entity;
9297 Write_Int (Int (S));
9298 Write_Str (" === ");
9299 Write_Name (Chars (S));
9308 procedure we (S : Entity_Id) is
9311 E := First_Entity (S);
9312 while Present (E) loop
9313 Write_Int (Int (E));
9314 Write_Str (" === ");
9315 Write_Name (Chars (E));