1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Disp
; use Exp_Disp
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Fname
; use Fname
;
35 with Freeze
; use Freeze
;
36 with Ghost
; use Ghost
;
37 with Impunit
; use Impunit
;
39 with Lib
.Load
; use Lib
.Load
;
40 with Lib
.Xref
; use Lib
.Xref
;
41 with Namet
; use Namet
;
42 with Namet
.Sp
; use Namet
.Sp
;
43 with Nlists
; use Nlists
;
44 with Nmake
; use Nmake
;
46 with Output
; use Output
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
51 with Sem_Aux
; use Sem_Aux
;
52 with Sem_Cat
; use Sem_Cat
;
53 with Sem_Ch3
; use Sem_Ch3
;
54 with Sem_Ch4
; use Sem_Ch4
;
55 with Sem_Ch6
; use Sem_Ch6
;
56 with Sem_Ch12
; use Sem_Ch12
;
57 with Sem_Ch13
; use Sem_Ch13
;
58 with Sem_Dim
; use Sem_Dim
;
59 with Sem_Disp
; use Sem_Disp
;
60 with Sem_Dist
; use Sem_Dist
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Res
; use Sem_Res
;
63 with Sem_Util
; use Sem_Util
;
64 with Sem_Type
; use Sem_Type
;
65 with Stand
; use Stand
;
66 with Sinfo
; use Sinfo
;
67 with Sinfo
.CN
; use Sinfo
.CN
;
68 with Snames
; use Snames
;
69 with Style
; use Style
;
71 with Targparm
; use Targparm
;
72 with Tbuild
; use Tbuild
;
73 with Uintp
; use Uintp
;
75 package body Sem_Ch8
is
77 ------------------------------------
78 -- Visibility and Name Resolution --
79 ------------------------------------
81 -- This package handles name resolution and the collection of possible
82 -- interpretations for overloaded names, prior to overload resolution.
84 -- Name resolution is the process that establishes a mapping between source
85 -- identifiers and the entities they denote at each point in the program.
86 -- Each entity is represented by a defining occurrence. Each identifier
87 -- that denotes an entity points to the corresponding defining occurrence.
88 -- This is the entity of the applied occurrence. Each occurrence holds
89 -- an index into the names table, where source identifiers are stored.
91 -- Each entry in the names table for an identifier or designator uses the
92 -- Info pointer to hold a link to the currently visible entity that has
93 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
94 -- in package Sem_Util). The visibility is initialized at the beginning of
95 -- semantic processing to make entities in package Standard immediately
96 -- visible. The visibility table is used in a more subtle way when
97 -- compiling subunits (see below).
99 -- Entities that have the same name (i.e. homonyms) are chained. In the
100 -- case of overloaded entities, this chain holds all the possible meanings
101 -- of a given identifier. The process of overload resolution uses type
102 -- information to select from this chain the unique meaning of a given
105 -- Entities are also chained in their scope, through the Next_Entity link.
106 -- As a consequence, the name space is organized as a sparse matrix, where
107 -- each row corresponds to a scope, and each column to a source identifier.
108 -- Open scopes, that is to say scopes currently being compiled, have their
109 -- corresponding rows of entities in order, innermost scope first.
111 -- The scopes of packages that are mentioned in context clauses appear in
112 -- no particular order, interspersed among open scopes. This is because
113 -- in the course of analyzing the context of a compilation, a package
114 -- declaration is first an open scope, and subsequently an element of the
115 -- context. If subunits or child units are present, a parent unit may
116 -- appear under various guises at various times in the compilation.
118 -- When the compilation of the innermost scope is complete, the entities
119 -- defined therein are no longer visible. If the scope is not a package
120 -- declaration, these entities are never visible subsequently, and can be
121 -- removed from visibility chains. If the scope is a package declaration,
122 -- its visible declarations may still be accessible. Therefore the entities
123 -- defined in such a scope are left on the visibility chains, and only
124 -- their visibility (immediately visibility or potential use-visibility)
127 -- The ordering of homonyms on their chain does not necessarily follow
128 -- the order of their corresponding scopes on the scope stack. For
129 -- example, if package P and the enclosing scope both contain entities
130 -- named E, then when compiling the package body the chain for E will
131 -- hold the global entity first, and the local one (corresponding to
132 -- the current inner scope) next. As a result, name resolution routines
133 -- do not assume any relative ordering of the homonym chains, either
134 -- for scope nesting or to order of appearance of context clauses.
136 -- When compiling a child unit, entities in the parent scope are always
137 -- immediately visible. When compiling the body of a child unit, private
138 -- entities in the parent must also be made immediately visible. There
139 -- are separate routines to make the visible and private declarations
140 -- visible at various times (see package Sem_Ch7).
142 -- +--------+ +-----+
143 -- | In use |-------->| EU1 |-------------------------->
144 -- +--------+ +-----+
146 -- +--------+ +-----+ +-----+
147 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
148 -- +--------+ +-----+ +-----+
150 -- +---------+ | +-----+
151 -- | with'ed |------------------------------>| EW2 |--->
152 -- +---------+ | +-----+
154 -- +--------+ +-----+ +-----+
155 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
156 -- +--------+ +-----+ +-----+
158 -- +--------+ +-----+ +-----+
159 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
160 -- +--------+ +-----+ +-----+
164 -- | | with'ed |----------------------------------------->
168 -- (innermost first) | |
169 -- +----------------------------+
170 -- Names table => | Id1 | | | | Id2 |
171 -- +----------------------------+
173 -- Name resolution must deal with several syntactic forms: simple names,
174 -- qualified names, indexed names, and various forms of calls.
176 -- Each identifier points to an entry in the names table. The resolution
177 -- of a simple name consists in traversing the homonym chain, starting
178 -- from the names table. If an entry is immediately visible, it is the one
179 -- designated by the identifier. If only potentially use-visible entities
180 -- are on the chain, we must verify that they do not hide each other. If
181 -- the entity we find is overloadable, we collect all other overloadable
182 -- entities on the chain as long as they are not hidden.
184 -- To resolve expanded names, we must find the entity at the intersection
185 -- of the entity chain for the scope (the prefix) and the homonym chain
186 -- for the selector. In general, homonym chains will be much shorter than
187 -- entity chains, so it is preferable to start from the names table as
188 -- well. If the entity found is overloadable, we must collect all other
189 -- interpretations that are defined in the scope denoted by the prefix.
191 -- For records, protected types, and tasks, their local entities are
192 -- removed from visibility chains on exit from the corresponding scope.
193 -- From the outside, these entities are always accessed by selected
194 -- notation, and the entity chain for the record type, protected type,
195 -- etc. is traversed sequentially in order to find the designated entity.
197 -- The discriminants of a type and the operations of a protected type or
198 -- task are unchained on exit from the first view of the type, (such as
199 -- a private or incomplete type declaration, or a protected type speci-
200 -- fication) and re-chained when compiling the second view.
202 -- In the case of operators, we do not make operators on derived types
203 -- explicit. As a result, the notation P."+" may denote either a user-
204 -- defined function with name "+", or else an implicit declaration of the
205 -- operator "+" in package P. The resolution of expanded names always
206 -- tries to resolve an operator name as such an implicitly defined entity,
207 -- in addition to looking for explicit declarations.
209 -- All forms of names that denote entities (simple names, expanded names,
210 -- character literals in some cases) have a Entity attribute, which
211 -- identifies the entity denoted by the name.
213 ---------------------
214 -- The Scope Stack --
215 ---------------------
217 -- The Scope stack keeps track of the scopes currently been compiled.
218 -- Every entity that contains declarations (including records) is placed
219 -- on the scope stack while it is being processed, and removed at the end.
220 -- Whenever a non-package scope is exited, the entities defined therein
221 -- are removed from the visibility table, so that entities in outer scopes
222 -- become visible (see previous description). On entry to Sem, the scope
223 -- stack only contains the package Standard. As usual, subunits complicate
224 -- this picture ever so slightly.
226 -- The Rtsfind mechanism can force a call to Semantics while another
227 -- compilation is in progress. The unit retrieved by Rtsfind must be
228 -- compiled in its own context, and has no access to the visibility of
229 -- the unit currently being compiled. The procedures Save_Scope_Stack and
230 -- Restore_Scope_Stack make entities in current open scopes invisible
231 -- before compiling the retrieved unit, and restore the compilation
232 -- environment afterwards.
234 ------------------------
235 -- Compiling subunits --
236 ------------------------
238 -- Subunits must be compiled in the environment of the corresponding stub,
239 -- that is to say with the same visibility into the parent (and its
240 -- context) that is available at the point of the stub declaration, but
241 -- with the additional visibility provided by the context clause of the
242 -- subunit itself. As a result, compilation of a subunit forces compilation
243 -- of the parent (see description in lib-). At the point of the stub
244 -- declaration, Analyze is called recursively to compile the proper body of
245 -- the subunit, but without reinitializing the names table, nor the scope
246 -- stack (i.e. standard is not pushed on the stack). In this fashion the
247 -- context of the subunit is added to the context of the parent, and the
248 -- subunit is compiled in the correct environment. Note that in the course
249 -- of processing the context of a subunit, Standard will appear twice on
250 -- the scope stack: once for the parent of the subunit, and once for the
251 -- unit in the context clause being compiled. However, the two sets of
252 -- entities are not linked by homonym chains, so that the compilation of
253 -- any context unit happens in a fresh visibility environment.
255 -------------------------------
256 -- Processing of USE Clauses --
257 -------------------------------
259 -- Every defining occurrence has a flag indicating if it is potentially use
260 -- visible. Resolution of simple names examines this flag. The processing
261 -- of use clauses consists in setting this flag on all visible entities
262 -- defined in the corresponding package. On exit from the scope of the use
263 -- clause, the corresponding flag must be reset. However, a package may
264 -- appear in several nested use clauses (pathological but legal, alas)
265 -- which forces us to use a slightly more involved scheme:
267 -- a) The defining occurrence for a package holds a flag -In_Use- to
268 -- indicate that it is currently in the scope of a use clause. If a
269 -- redundant use clause is encountered, then the corresponding occurrence
270 -- of the package name is flagged -Redundant_Use-.
272 -- b) On exit from a scope, the use clauses in its declarative part are
273 -- scanned. The visibility flag is reset in all entities declared in
274 -- package named in a use clause, as long as the package is not flagged
275 -- as being in a redundant use clause (in which case the outer use
276 -- clause is still in effect, and the direct visibility of its entities
277 -- must be retained).
279 -- Note that entities are not removed from their homonym chains on exit
280 -- from the package specification. A subsequent use clause does not need
281 -- to rechain the visible entities, but only to establish their direct
284 -----------------------------------
285 -- Handling private declarations --
286 -----------------------------------
288 -- The principle that each entity has a single defining occurrence clashes
289 -- with the presence of two separate definitions for private types: the
290 -- first is the private type declaration, and second is the full type
291 -- declaration. It is important that all references to the type point to
292 -- the same defining occurrence, namely the first one. To enforce the two
293 -- separate views of the entity, the corresponding information is swapped
294 -- between the two declarations. Outside of the package, the defining
295 -- occurrence only contains the private declaration information, while in
296 -- the private part and the body of the package the defining occurrence
297 -- contains the full declaration. To simplify the swap, the defining
298 -- occurrence that currently holds the private declaration points to the
299 -- full declaration. During semantic processing the defining occurrence
300 -- also points to a list of private dependents, that is to say access types
301 -- or composite types whose designated types or component types are
302 -- subtypes or derived types of the private type in question. After the
303 -- full declaration has been seen, the private dependents are updated to
304 -- indicate that they have full definitions.
306 ------------------------------------
307 -- Handling of Undefined Messages --
308 ------------------------------------
310 -- In normal mode, only the first use of an undefined identifier generates
311 -- a message. The table Urefs is used to record error messages that have
312 -- been issued so that second and subsequent ones do not generate further
313 -- messages. However, the second reference causes text to be added to the
314 -- original undefined message noting "(more references follow)". The
315 -- full error list option (-gnatf) forces messages to be generated for
316 -- every reference and disconnects the use of this table.
318 type Uref_Entry
is record
320 -- Node for identifier for which original message was posted. The
321 -- Chars field of this identifier is used to detect later references
322 -- to the same identifier.
325 -- Records error message Id of original undefined message. Reset to
326 -- No_Error_Msg after the second occurrence, where it is used to add
327 -- text to the original message as described above.
330 -- Set if the message is not visible rather than undefined
333 -- Records location of error message. Used to make sure that we do
334 -- not consider a, b : undefined as two separate instances, which
335 -- would otherwise happen, since the parser converts this sequence
336 -- to a : undefined; b : undefined.
340 package Urefs
is new Table
.Table
(
341 Table_Component_Type
=> Uref_Entry
,
342 Table_Index_Type
=> Nat
,
343 Table_Low_Bound
=> 1,
345 Table_Increment
=> 100,
346 Table_Name
=> "Urefs");
348 Candidate_Renaming
: Entity_Id
;
349 -- Holds a candidate interpretation that appears in a subprogram renaming
350 -- declaration and does not match the given specification, but matches at
351 -- least on the first formal. Allows better error message when given
352 -- specification omits defaulted parameters, a common error.
354 -----------------------
355 -- Local Subprograms --
356 -----------------------
358 procedure Analyze_Generic_Renaming
361 -- Common processing for all three kinds of generic renaming declarations.
362 -- Enter new name and indicate that it renames the generic unit.
364 procedure Analyze_Renamed_Character
368 -- Renamed entity is given by a character literal, which must belong
369 -- to the return type of the new entity. Is_Body indicates whether the
370 -- declaration is a renaming_as_body. If the original declaration has
371 -- already been frozen (because of an intervening body, e.g.) the body of
372 -- the function must be built now. The same applies to the following
373 -- various renaming procedures.
375 procedure Analyze_Renamed_Dereference
379 -- Renamed entity is given by an explicit dereference. Prefix must be a
380 -- conformant access_to_subprogram type.
382 procedure Analyze_Renamed_Entry
386 -- If the renamed entity in a subprogram renaming is an entry or protected
387 -- subprogram, build a body for the new entity whose only statement is a
388 -- call to the renamed entity.
390 procedure Analyze_Renamed_Family_Member
394 -- Used when the renamed entity is an indexed component. The prefix must
395 -- denote an entry family.
397 procedure Analyze_Renamed_Primitive_Operation
401 -- If the renamed entity in a subprogram renaming is a primitive operation
402 -- or a class-wide operation in prefix form, save the target object,
403 -- which must be added to the list of actuals in any subsequent call.
404 -- The renaming operation is intrinsic because the compiler must in
405 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
407 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
408 -- Common code to Use_One_Package and Set_Use, to determine whether use
409 -- clause must be processed. Pack_Name is an entity name that references
410 -- the package in question.
412 procedure Attribute_Renaming
(N
: Node_Id
);
413 -- Analyze renaming of attribute as subprogram. The renaming declaration N
414 -- is rewritten as a subprogram body that returns the attribute reference
415 -- applied to the formals of the function.
417 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
418 -- Set Entity, with style check if need be. For a discriminant reference,
419 -- replace by the corresponding discriminal, i.e. the parameter of the
420 -- initialization procedure that corresponds to the discriminant.
422 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
423 -- A renaming_as_body may occur after the entity of the original decla-
424 -- ration has been frozen. In that case, the body of the new entity must
425 -- be built now, because the usual mechanism of building the renamed
426 -- body at the point of freezing will not work. Subp is the subprogram
427 -- for which N provides the Renaming_As_Body.
429 procedure Check_In_Previous_With_Clause
432 -- N is a use_package clause and Nam the package name, or N is a use_type
433 -- clause and Nam is the prefix of the type name. In either case, verify
434 -- that the package is visible at that point in the context: either it
435 -- appears in a previous with_clause, or because it is a fully qualified
436 -- name and the root ancestor appears in a previous with_clause.
438 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
439 -- Verify that the entity in a renaming declaration that is a library unit
440 -- is itself a library unit and not a nested unit or subunit. Also check
441 -- that if the renaming is a child unit of a generic parent, then the
442 -- renamed unit must also be a child unit of that parent. Finally, verify
443 -- that a renamed generic unit is not an implicit child declared within
444 -- an instance of the parent.
446 procedure Chain_Use_Clause
(N
: Node_Id
);
447 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
448 -- the proper scope table entry. This is usually the current scope, but it
449 -- will be an inner scope when installing the use clauses of the private
450 -- declarations of a parent unit prior to compiling the private part of a
451 -- child unit. This chain is traversed when installing/removing use clauses
452 -- when compiling a subunit or instantiating a generic body on the fly,
453 -- when it is necessary to save and restore full environments.
455 function Enclosing_Instance
return Entity_Id
;
456 -- In an instance nested within another one, several semantic checks are
457 -- unnecessary because the legality of the nested instance has been checked
458 -- in the enclosing generic unit. This applies in particular to legality
459 -- checks on actuals for formal subprograms of the inner instance, which
460 -- are checked as subprogram renamings, and may be complicated by confusion
461 -- in private/full views. This function returns the instance enclosing the
462 -- current one if there is such, else it returns Empty.
464 -- If the renaming determines the entity for the default of a formal
465 -- subprogram nested within another instance, choose the innermost
466 -- candidate. This is because if the formal has a box, and we are within
467 -- an enclosing instance where some candidate interpretations are local
468 -- to this enclosing instance, we know that the default was properly
469 -- resolved when analyzing the generic, so we prefer the local
470 -- candidates to those that are external. This is not always the case
471 -- but is a reasonable heuristic on the use of nested generics. The
472 -- proper solution requires a full renaming model.
474 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
475 -- Find a type derived from Character or Wide_Character in the prefix of N.
476 -- Used to resolved qualified names whose selector is a character literal.
478 function Has_Private_With
(E
: Entity_Id
) return Boolean;
479 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
480 -- private with on E.
482 procedure Find_Expanded_Name
(N
: Node_Id
);
483 -- The input is a selected component known to be an expanded name. Verify
484 -- legality of selector given the scope denoted by prefix, and change node
485 -- N into a expanded name with a properly set Entity field.
487 function Find_Renamed_Entity
491 Is_Actual
: Boolean := False) return Entity_Id
;
492 -- Find the renamed entity that corresponds to the given parameter profile
493 -- in a subprogram renaming declaration. The renamed entity may be an
494 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
495 -- indicates that the renaming is the one generated for an actual subpro-
496 -- gram in an instance, for which special visibility checks apply.
498 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
499 -- N is an expanded name whose selector is an operator name (e.g. P."+").
500 -- declarative part contains an implicit declaration of an operator if it
501 -- has a declaration of a type to which one of the predefined operators
502 -- apply. The existence of this routine is an implementation artifact. A
503 -- more straightforward but more space-consuming choice would be to make
504 -- all inherited operators explicit in the symbol table.
506 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
507 -- A subprogram defined by a renaming declaration inherits the parameter
508 -- profile of the renamed entity. The subtypes given in the subprogram
509 -- specification are discarded and replaced with those of the renamed
510 -- subprogram, which are then used to recheck the default values.
512 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
513 -- Prefix is appropriate for record if it is of a record type, or an access
516 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
517 -- True if it is of a task type, a protected type, or else an access to one
520 procedure Note_Redundant_Use
(Clause
: Node_Id
);
521 -- Mark the name in a use clause as redundant if the corresponding entity
522 -- is already use-visible. Emit a warning if the use clause comes from
523 -- source and the proper warnings are enabled.
525 procedure Premature_Usage
(N
: Node_Id
);
526 -- Diagnose usage of an entity before it is visible
528 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
529 -- Make visible entities declared in package P potentially use-visible
530 -- in the current context. Also used in the analysis of subunits, when
531 -- re-installing use clauses of parent units. N is the use_clause that
532 -- names P (and possibly other packages).
534 procedure Use_One_Type
(Id
: Node_Id
; Installed
: Boolean := False);
535 -- Id is the subtype mark from a use type clause. This procedure makes
536 -- the primitive operators of the type potentially use-visible. The
537 -- boolean flag Installed indicates that the clause is being reinstalled
538 -- after previous analysis, and primitive operations are already chained
539 -- on the Used_Operations list of the clause.
541 procedure Write_Info
;
542 -- Write debugging information on entities declared in current scope
544 --------------------------------
545 -- Analyze_Exception_Renaming --
546 --------------------------------
548 -- The language only allows a single identifier, but the tree holds an
549 -- identifier list. The parser has already issued an error message if
550 -- there is more than one element in the list.
552 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
553 Id
: constant Node_Id
:= Defining_Identifier
(N
);
554 Nam
: constant Node_Id
:= Name
(N
);
557 -- The exception renaming declaration may be subject to pragma Ghost
558 -- with policy Ignore. Set the mode now to ensure that any nodes
559 -- generated during analysis and expansion are properly flagged as
563 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
568 Set_Ekind
(Id
, E_Exception
);
569 Set_Etype
(Id
, Standard_Exception_Type
);
570 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
572 if not Is_Entity_Name
(Nam
)
573 or else Ekind
(Entity
(Nam
)) /= E_Exception
575 Error_Msg_N
("invalid exception name in renaming", Nam
);
577 if Present
(Renamed_Object
(Entity
(Nam
))) then
578 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
580 Set_Renamed_Object
(Id
, Entity
(Nam
));
583 -- An exception renaming is Ghost if the renamed entity is Ghost or
584 -- the construct appears within a Ghost scope.
586 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
587 Set_Is_Ghost_Entity
(Id
);
591 -- Implementation-defined aspect specifications can appear in a renaming
592 -- declaration, but not language-defined ones. The call to procedure
593 -- Analyze_Aspect_Specifications will take care of this error check.
595 if Has_Aspects
(N
) then
596 Analyze_Aspect_Specifications
(N
, Id
);
598 end Analyze_Exception_Renaming
;
600 ---------------------------
601 -- Analyze_Expanded_Name --
602 ---------------------------
604 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
606 -- If the entity pointer is already set, this is an internal node, or a
607 -- node that is analyzed more than once, after a tree modification. In
608 -- such a case there is no resolution to perform, just set the type. For
609 -- completeness, analyze prefix as well.
611 if Present
(Entity
(N
)) then
612 if Is_Type
(Entity
(N
)) then
613 Set_Etype
(N
, Entity
(N
));
615 Set_Etype
(N
, Etype
(Entity
(N
)));
618 Analyze
(Prefix
(N
));
621 Find_Expanded_Name
(N
);
624 Analyze_Dimension
(N
);
625 end Analyze_Expanded_Name
;
627 ---------------------------------------
628 -- Analyze_Generic_Function_Renaming --
629 ---------------------------------------
631 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
633 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
634 end Analyze_Generic_Function_Renaming
;
636 --------------------------------------
637 -- Analyze_Generic_Package_Renaming --
638 --------------------------------------
640 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
642 -- Test for the Text_IO special unit case here, since we may be renaming
643 -- one of the subpackages of Text_IO, then join common routine.
645 Check_Text_IO_Special_Unit
(Name
(N
));
647 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
648 end Analyze_Generic_Package_Renaming
;
650 ----------------------------------------
651 -- Analyze_Generic_Procedure_Renaming --
652 ----------------------------------------
654 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
656 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
657 end Analyze_Generic_Procedure_Renaming
;
659 ------------------------------
660 -- Analyze_Generic_Renaming --
661 ------------------------------
663 procedure Analyze_Generic_Renaming
667 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
669 Inst
: Boolean := False; -- prevent junk warning
672 if Name
(N
) = Error
then
676 -- The generic renaming declaration may be subject to pragma Ghost with
677 -- policy Ignore. Set the mode now to ensure that any nodes generated
678 -- during analysis and expansion are properly flagged as ignored Ghost.
681 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
683 Generate_Definition
(New_P
);
685 if Current_Scope
/= Standard_Standard
then
686 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
689 if Nkind
(Name
(N
)) = N_Selected_Component
then
690 Check_Generic_Child_Unit
(Name
(N
), Inst
);
695 if not Is_Entity_Name
(Name
(N
)) then
696 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
699 Old_P
:= Entity
(Name
(N
));
703 Set_Ekind
(New_P
, K
);
705 if Etype
(Old_P
) = Any_Type
then
708 elsif Ekind
(Old_P
) /= K
then
709 Error_Msg_N
("invalid generic unit name", Name
(N
));
712 if Present
(Renamed_Object
(Old_P
)) then
713 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
715 Set_Renamed_Object
(New_P
, Old_P
);
718 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
719 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
721 Set_Etype
(New_P
, Etype
(Old_P
));
722 Set_Has_Completion
(New_P
);
724 -- An generic renaming is Ghost if the renamed entity is Ghost or the
725 -- construct appears within a Ghost scope.
727 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
728 Set_Is_Ghost_Entity
(New_P
);
731 if In_Open_Scopes
(Old_P
) then
732 Error_Msg_N
("within its scope, generic denotes its instance", N
);
735 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
736 -- renamings and subsequent instantiations of Unchecked_Conversion.
738 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
739 Set_Is_Intrinsic_Subprogram
740 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
743 Check_Library_Unit_Renaming
(N
, Old_P
);
746 -- Implementation-defined aspect specifications can appear in a renaming
747 -- declaration, but not language-defined ones. The call to procedure
748 -- Analyze_Aspect_Specifications will take care of this error check.
750 if Has_Aspects
(N
) then
751 Analyze_Aspect_Specifications
(N
, New_P
);
753 end Analyze_Generic_Renaming
;
755 -----------------------------
756 -- Analyze_Object_Renaming --
757 -----------------------------
759 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
760 Loc
: constant Source_Ptr
:= Sloc
(N
);
761 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
763 Nam
: constant Node_Id
:= Name
(N
);
767 procedure Check_Constrained_Object
;
768 -- If the nominal type is unconstrained but the renamed object is
769 -- constrained, as can happen with renaming an explicit dereference or
770 -- a function return, build a constrained subtype from the object. If
771 -- the renaming is for a formal in an accept statement, the analysis
772 -- has already established its actual subtype. This is only relevant
773 -- if the renamed object is an explicit dereference.
775 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
776 -- Determine whether entity E is inside a generic cope
778 ------------------------------
779 -- Check_Constrained_Object --
780 ------------------------------
782 procedure Check_Constrained_Object
is
783 Typ
: constant Entity_Id
:= Etype
(Nam
);
787 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
788 and then Is_Composite_Type
(Etype
(Nam
))
789 and then not Is_Constrained
(Etype
(Nam
))
790 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
791 and then Expander_Active
793 -- If Actual_Subtype is already set, nothing to do
795 if Ekind_In
(Id
, E_Variable
, E_Constant
)
796 and then Present
(Actual_Subtype
(Id
))
800 -- A renaming of an unchecked union has no actual subtype
802 elsif Is_Unchecked_Union
(Typ
) then
805 -- If a record is limited its size is invariant. This is the case
806 -- in particular with record types with an access discirminant
807 -- that are used in iterators. This is an optimization, but it
808 -- also prevents typing anomalies when the prefix is further
809 -- expanded. Limited types with discriminants are included.
811 elsif Is_Limited_Record
(Typ
)
813 (Ekind
(Typ
) = E_Limited_Private_Type
814 and then Has_Discriminants
(Typ
)
815 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
820 Subt
:= Make_Temporary
(Loc
, 'T');
821 Remove_Side_Effects
(Nam
);
823 Make_Subtype_Declaration
(Loc
,
824 Defining_Identifier
=> Subt
,
825 Subtype_Indication
=>
826 Make_Subtype_From_Expr
(Nam
, Typ
)));
827 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
828 Set_Etype
(Nam
, Subt
);
830 -- Freeze subtype at once, to prevent order of elaboration
831 -- issues in the backend. The renamed object exists, so its
832 -- type is already frozen in any case.
834 Freeze_Before
(N
, Subt
);
837 end Check_Constrained_Object
;
839 ----------------------
840 -- In_Generic_Scope --
841 ----------------------
843 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
848 while Present
(S
) and then S
/= Standard_Standard
loop
849 if Is_Generic_Unit
(S
) then
857 end In_Generic_Scope
;
859 -- Start of processing for Analyze_Object_Renaming
866 -- The object renaming declaration may be subject to pragma Ghost with
867 -- policy Ignore. Set the mode now to ensure that any nodes generated
868 -- during analysis and expansion are properly flagged as ignored Ghost.
871 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
873 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
876 -- The renaming of a component that depends on a discriminant requires
877 -- an actual subtype, because in subsequent use of the object Gigi will
878 -- be unable to locate the actual bounds. This explicit step is required
879 -- when the renaming is generated in removing side effects of an
880 -- already-analyzed expression.
882 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
884 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
886 if Present
(Dec
) then
887 Insert_Action
(N
, Dec
);
888 T
:= Defining_Identifier
(Dec
);
892 -- Complete analysis of the subtype mark in any case, for ASIS use
894 if Present
(Subtype_Mark
(N
)) then
895 Find_Type
(Subtype_Mark
(N
));
898 elsif Present
(Subtype_Mark
(N
)) then
899 Find_Type
(Subtype_Mark
(N
));
900 T
:= Entity
(Subtype_Mark
(N
));
903 -- Reject renamings of conversions unless the type is tagged, or
904 -- the conversion is implicit (which can occur for cases of anonymous
905 -- access types in Ada 2012).
907 if Nkind
(Nam
) = N_Type_Conversion
908 and then Comes_From_Source
(Nam
)
909 and then not Is_Tagged_Type
(T
)
912 ("renaming of conversion only allowed for tagged types", Nam
);
917 -- If the renamed object is a function call of a limited type,
918 -- the expansion of the renaming is complicated by the presence
919 -- of various temporaries and subtypes that capture constraints
920 -- of the renamed object. Rewrite node as an object declaration,
921 -- whose expansion is simpler. Given that the object is limited
922 -- there is no copy involved and no performance hit.
924 if Nkind
(Nam
) = N_Function_Call
925 and then Is_Limited_View
(Etype
(Nam
))
926 and then not Is_Constrained
(Etype
(Nam
))
927 and then Comes_From_Source
(N
)
930 Set_Ekind
(Id
, E_Constant
);
932 Make_Object_Declaration
(Loc
,
933 Defining_Identifier
=> Id
,
934 Constant_Present
=> True,
935 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
936 Expression
=> Relocate_Node
(Nam
)));
940 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
941 -- when renaming declaration has a named access type. The Ada 2012
942 -- coverage rules allow an anonymous access type in the context of
943 -- an expected named general access type, but the renaming rules
944 -- require the types to be the same. (An exception is when the type
945 -- of the renaming is also an anonymous access type, which can only
946 -- happen due to a renaming created by the expander.)
948 if Nkind
(Nam
) = N_Type_Conversion
949 and then not Comes_From_Source
(Nam
)
950 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
951 and then Ekind
(T
) /= E_Anonymous_Access_Type
953 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
956 -- Check that a class-wide object is not being renamed as an object
957 -- of a specific type. The test for access types is needed to exclude
958 -- cases where the renamed object is a dynamically tagged access
959 -- result, such as occurs in certain expansions.
961 if Is_Tagged_Type
(T
) then
962 Check_Dynamically_Tagged_Expression
968 -- Ada 2005 (AI-230/AI-254): Access renaming
970 else pragma Assert
(Present
(Access_Definition
(N
)));
971 T
:= Access_Definition
973 N
=> Access_Definition
(N
));
977 -- Ada 2005 AI05-105: if the declaration has an anonymous access
978 -- type, the renamed object must also have an anonymous type, and
979 -- this is a name resolution rule. This was implicit in the last part
980 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
983 if not Is_Overloaded
(Nam
) then
984 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
986 ("expect anonymous access type in object renaming", N
);
993 Typ
: Entity_Id
:= Empty
;
994 Seen
: Boolean := False;
997 Get_First_Interp
(Nam
, I
, It
);
998 while Present
(It
.Typ
) loop
1000 -- Renaming is ambiguous if more than one candidate
1001 -- interpretation is type-conformant with the context.
1003 if Ekind
(It
.Typ
) = Ekind
(T
) then
1004 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
1007 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
1013 ("ambiguous expression in renaming", Nam
);
1016 elsif Ekind
(T
) = E_Anonymous_Access_Type
1018 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1024 ("ambiguous expression in renaming", Nam
);
1028 if Covers
(T
, It
.Typ
) then
1030 Set_Etype
(Nam
, Typ
);
1031 Set_Is_Overloaded
(Nam
, False);
1035 Get_Next_Interp
(I
, It
);
1042 -- Ada 2005 (AI-231): In the case where the type is defined by an
1043 -- access_definition, the renamed entity shall be of an access-to-
1044 -- constant type if and only if the access_definition defines an
1045 -- access-to-constant type. ARM 8.5.1(4)
1047 if Constant_Present
(Access_Definition
(N
))
1048 and then not Is_Access_Constant
(Etype
(Nam
))
1050 Error_Msg_N
("(Ada 2005): the renamed object is not "
1051 & "access-to-constant (RM 8.5.1(6))", N
);
1053 elsif not Constant_Present
(Access_Definition
(N
))
1054 and then Is_Access_Constant
(Etype
(Nam
))
1056 Error_Msg_N
("(Ada 2005): the renamed object is not "
1057 & "access-to-variable (RM 8.5.1(6))", N
);
1060 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1061 Check_Subtype_Conformant
1062 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1064 elsif not Subtypes_Statically_Match
1065 (Designated_Type
(T
),
1066 Available_View
(Designated_Type
(Etype
(Nam
))))
1069 ("subtype of renamed object does not statically match", N
);
1073 -- Special processing for renaming function return object. Some errors
1074 -- and warnings are produced only for calls that come from source.
1076 if Nkind
(Nam
) = N_Function_Call
then
1079 -- Usage is illegal in Ada 83, but renamings are also introduced
1080 -- during expansion, and error does not apply to those.
1083 if Comes_From_Source
(N
) then
1085 ("(Ada 83) cannot rename function return object", Nam
);
1088 -- In Ada 95, warn for odd case of renaming parameterless function
1089 -- call if this is not a limited type (where this is useful).
1092 if Warn_On_Object_Renames_Function
1093 and then No
(Parameter_Associations
(Nam
))
1094 and then not Is_Limited_Type
(Etype
(Nam
))
1095 and then Comes_From_Source
(Nam
)
1098 ("renaming function result object is suspicious?R?", Nam
);
1100 ("\function & will be called only once?R?", Nam
,
1101 Entity
(Name
(Nam
)));
1102 Error_Msg_N
-- CODEFIX
1103 ("\suggest using an initialized constant "
1104 & "object instead?R?", Nam
);
1110 Check_Constrained_Object
;
1112 -- An object renaming requires an exact match of the type. Class-wide
1113 -- matching is not allowed.
1115 if Is_Class_Wide_Type
(T
)
1116 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1118 Wrong_Type
(Nam
, T
);
1123 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1125 if Nkind
(Nam
) = N_Explicit_Dereference
1126 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1128 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1131 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1132 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1136 -- Ada 2005 (AI-327)
1138 if Ada_Version
>= Ada_2005
1139 and then Nkind
(Nam
) = N_Attribute_Reference
1140 and then Attribute_Name
(Nam
) = Name_Priority
1144 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1147 Nam_Ent
: Entity_Id
;
1150 if Nkind
(Nam
) = N_Attribute_Reference
then
1151 Nam_Ent
:= Entity
(Prefix
(Nam
));
1153 Nam_Ent
:= Entity
(Nam
);
1156 Nam_Decl
:= Parent
(Nam_Ent
);
1158 if Has_Null_Exclusion
(N
)
1159 and then not Has_Null_Exclusion
(Nam_Decl
)
1161 -- Ada 2005 (AI-423): If the object name denotes a generic
1162 -- formal object of a generic unit G, and the object renaming
1163 -- declaration occurs within the body of G or within the body
1164 -- of a generic unit declared within the declarative region
1165 -- of G, then the declaration of the formal object of G must
1166 -- have a null exclusion or a null-excluding subtype.
1168 if Is_Formal_Object
(Nam_Ent
)
1169 and then In_Generic_Scope
(Id
)
1171 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1173 ("renamed formal does not exclude `NULL` "
1174 & "(RM 8.5.1(4.6/2))", N
);
1176 elsif In_Package_Body
(Scope
(Id
)) then
1178 ("formal object does not have a null exclusion"
1179 & "(RM 8.5.1(4.6/2))", N
);
1182 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1183 -- shall exclude null.
1185 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1187 ("renamed object does not exclude `NULL` "
1188 & "(RM 8.5.1(4.6/2))", N
);
1190 -- An instance is illegal if it contains a renaming that
1191 -- excludes null, and the actual does not. The renaming
1192 -- declaration has already indicated that the declaration
1193 -- of the renamed actual in the instance will raise
1194 -- constraint_error.
1196 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1197 and then In_Instance
1199 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1200 and then Nkind
(Expression
(Nam_Decl
)) =
1201 N_Raise_Constraint_Error
1204 ("renamed actual does not exclude `NULL` "
1205 & "(RM 8.5.1(4.6/2))", N
);
1207 -- Finally, if there is a null exclusion, the subtype mark
1208 -- must not be null-excluding.
1210 elsif No
(Access_Definition
(N
))
1211 and then Can_Never_Be_Null
(T
)
1214 ("`NOT NULL` not allowed (& already excludes null)",
1219 elsif Can_Never_Be_Null
(T
)
1220 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1223 ("renamed object does not exclude `NULL` "
1224 & "(RM 8.5.1(4.6/2))", N
);
1226 elsif Has_Null_Exclusion
(N
)
1227 and then No
(Access_Definition
(N
))
1228 and then Can_Never_Be_Null
(T
)
1231 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1236 -- Set the Ekind of the entity, unless it has been set already, as is
1237 -- the case for the iteration object over a container with no variable
1238 -- indexing. In that case it's been marked as a constant, and we do not
1239 -- want to change it to a variable.
1241 if Ekind
(Id
) /= E_Constant
then
1242 Set_Ekind
(Id
, E_Variable
);
1245 -- Initialize the object size and alignment. Note that we used to call
1246 -- Init_Size_Align here, but that's wrong for objects which have only
1247 -- an Esize, not an RM_Size field.
1249 Init_Object_Size_Align
(Id
);
1251 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1254 -- Verify that the renamed entity is an object or a function call. It
1255 -- may have been rewritten in several ways.
1257 elsif Is_Object_Reference
(Nam
) then
1258 if Comes_From_Source
(N
) then
1259 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1261 ("illegal renaming of discriminant-dependent component", Nam
);
1264 -- If the renaming comes from source and the renamed object is a
1265 -- dereference, then mark the prefix as needing debug information,
1266 -- since it might have been rewritten hence internally generated
1267 -- and Debug_Renaming_Declaration will link the renaming to it.
1269 if Nkind
(Nam
) = N_Explicit_Dereference
1270 and then Is_Entity_Name
(Prefix
(Nam
))
1272 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1276 -- A static function call may have been folded into a literal
1278 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1280 -- When expansion is disabled, attribute reference is not rewritten
1281 -- as function call. Otherwise it may be rewritten as a conversion,
1282 -- so check original node.
1284 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1285 and then Is_Function_Attribute_Name
1286 (Attribute_Name
(Original_Node
(Nam
))))
1288 -- Weird but legal, equivalent to renaming a function call. Illegal
1289 -- if the literal is the result of constant-folding an attribute
1290 -- reference that is not a function.
1292 or else (Is_Entity_Name
(Nam
)
1293 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1295 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1297 or else (Nkind
(Nam
) = N_Type_Conversion
1298 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1302 elsif Nkind
(Nam
) = N_Type_Conversion
then
1304 ("renaming of conversion only allowed for tagged types", Nam
);
1306 -- Ada 2005 (AI-327)
1308 elsif Ada_Version
>= Ada_2005
1309 and then Nkind
(Nam
) = N_Attribute_Reference
1310 and then Attribute_Name
(Nam
) = Name_Priority
1314 -- Allow internally generated x'Reference expression
1316 elsif Nkind
(Nam
) = N_Reference
then
1320 Error_Msg_N
("expect object name in renaming", Nam
);
1325 if not Is_Variable
(Nam
) then
1326 Set_Ekind
(Id
, E_Constant
);
1327 Set_Never_Set_In_Source
(Id
, True);
1328 Set_Is_True_Constant
(Id
, True);
1331 -- An object renaming is Ghost if the renamed entity is Ghost or the
1332 -- construct appears within a Ghost scope.
1334 if (Is_Entity_Name
(Nam
)
1335 and then Is_Ghost_Entity
(Entity
(Nam
)))
1336 or else Ghost_Mode
> None
1338 Set_Is_Ghost_Entity
(Id
);
1341 -- The entity of the renaming declaration needs to reflect whether the
1342 -- renamed object is volatile. Is_Volatile is set if the renamed object
1343 -- is volatile in the RM legality sense.
1345 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1347 -- Treat as volatile if we just set the Volatile flag
1351 -- Or if we are renaming an entity which was marked this way
1353 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1355 or else (Is_Entity_Name
(Nam
)
1356 and then Treat_As_Volatile
(Entity
(Nam
)))
1358 Set_Treat_As_Volatile
(Id
, True);
1361 -- Now make the link to the renamed object
1363 Set_Renamed_Object
(Id
, Nam
);
1365 -- Implementation-defined aspect specifications can appear in a renaming
1366 -- declaration, but not language-defined ones. The call to procedure
1367 -- Analyze_Aspect_Specifications will take care of this error check.
1369 if Has_Aspects
(N
) then
1370 Analyze_Aspect_Specifications
(N
, Id
);
1373 -- Deal with dimensions
1375 Analyze_Dimension
(N
);
1376 end Analyze_Object_Renaming
;
1378 ------------------------------
1379 -- Analyze_Package_Renaming --
1380 ------------------------------
1382 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1383 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1388 if Name
(N
) = Error
then
1392 -- The package renaming declaration may be subject to pragma Ghost with
1393 -- policy Ignore. Set the mode now to ensure that any nodes generated
1394 -- during analysis and expansion are properly flagged as ignored Ghost.
1398 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1400 Check_Text_IO_Special_Unit
(Name
(N
));
1402 if Current_Scope
/= Standard_Standard
then
1403 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1409 if Is_Entity_Name
(Name
(N
)) then
1410 Old_P
:= Entity
(Name
(N
));
1415 if Etype
(Old_P
) = Any_Type
then
1416 Error_Msg_N
("expect package name in renaming", Name
(N
));
1418 elsif Ekind
(Old_P
) /= E_Package
1419 and then not (Ekind
(Old_P
) = E_Generic_Package
1420 and then In_Open_Scopes
(Old_P
))
1422 if Ekind
(Old_P
) = E_Generic_Package
then
1424 ("generic package cannot be renamed as a package", Name
(N
));
1426 Error_Msg_Sloc
:= Sloc
(Old_P
);
1428 ("expect package name in renaming, found& declared#",
1432 -- Set basic attributes to minimize cascaded errors
1434 Set_Ekind
(New_P
, E_Package
);
1435 Set_Etype
(New_P
, Standard_Void_Type
);
1437 -- Here for OK package renaming
1440 -- Entities in the old package are accessible through the renaming
1441 -- entity. The simplest implementation is to have both packages share
1444 Set_Ekind
(New_P
, E_Package
);
1445 Set_Etype
(New_P
, Standard_Void_Type
);
1447 if Present
(Renamed_Object
(Old_P
)) then
1448 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1450 Set_Renamed_Object
(New_P
, Old_P
);
1453 Set_Has_Completion
(New_P
);
1455 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1456 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1457 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1458 Check_Library_Unit_Renaming
(N
, Old_P
);
1459 Generate_Reference
(Old_P
, Name
(N
));
1461 -- A package renaming is Ghost if the renamed entity is Ghost or
1462 -- the construct appears within a Ghost scope.
1464 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
1465 Set_Is_Ghost_Entity
(New_P
);
1468 -- If the renaming is in the visible part of a package, then we set
1469 -- Renamed_In_Spec for the renamed package, to prevent giving
1470 -- warnings about no entities referenced. Such a warning would be
1471 -- overenthusiastic, since clients can see entities in the renamed
1472 -- package via the visible package renaming.
1475 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1477 if Ekind
(Ent
) = E_Package
1478 and then not In_Private_Part
(Ent
)
1479 and then In_Extended_Main_Source_Unit
(N
)
1480 and then Ekind
(Old_P
) = E_Package
1482 Set_Renamed_In_Spec
(Old_P
);
1486 -- If this is the renaming declaration of a package instantiation
1487 -- within itself, it is the declaration that ends the list of actuals
1488 -- for the instantiation. At this point, the subtypes that rename
1489 -- the actuals are flagged as generic, to avoid spurious ambiguities
1490 -- if the actuals for two distinct formals happen to coincide. If
1491 -- the actual is a private type, the subtype has a private completion
1492 -- that is flagged in the same fashion.
1494 -- Resolution is identical to what is was in the original generic.
1495 -- On exit from the generic instance, these are turned into regular
1496 -- subtypes again, so they are compatible with types in their class.
1498 if not Is_Generic_Instance
(Old_P
) then
1501 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1504 if Nkind
(Spec
) = N_Package_Specification
1505 and then Present
(Generic_Parent
(Spec
))
1506 and then Old_P
= Current_Scope
1507 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1513 E
:= First_Entity
(Old_P
);
1514 while Present
(E
) and then E
/= New_P
loop
1516 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1518 Set_Is_Generic_Actual_Type
(E
);
1520 if Is_Private_Type
(E
)
1521 and then Present
(Full_View
(E
))
1523 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1533 -- Implementation-defined aspect specifications can appear in a renaming
1534 -- declaration, but not language-defined ones. The call to procedure
1535 -- Analyze_Aspect_Specifications will take care of this error check.
1537 if Has_Aspects
(N
) then
1538 Analyze_Aspect_Specifications
(N
, New_P
);
1540 end Analyze_Package_Renaming
;
1542 -------------------------------
1543 -- Analyze_Renamed_Character --
1544 -------------------------------
1546 procedure Analyze_Renamed_Character
1551 C
: constant Node_Id
:= Name
(N
);
1554 if Ekind
(New_S
) = E_Function
then
1555 Resolve
(C
, Etype
(New_S
));
1558 Check_Frozen_Renaming
(N
, New_S
);
1562 Error_Msg_N
("character literal can only be renamed as function", N
);
1564 end Analyze_Renamed_Character
;
1566 ---------------------------------
1567 -- Analyze_Renamed_Dereference --
1568 ---------------------------------
1570 procedure Analyze_Renamed_Dereference
1575 Nam
: constant Node_Id
:= Name
(N
);
1576 P
: constant Node_Id
:= Prefix
(Nam
);
1582 if not Is_Overloaded
(P
) then
1583 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1584 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1586 Error_Msg_N
("designated type does not match specification", P
);
1595 Get_First_Interp
(Nam
, Ind
, It
);
1597 while Present
(It
.Nam
) loop
1599 if Ekind
(It
.Nam
) = E_Subprogram_Type
1600 and then Type_Conformant
(It
.Nam
, New_S
)
1602 if Typ
/= Any_Id
then
1603 Error_Msg_N
("ambiguous renaming", P
);
1610 Get_Next_Interp
(Ind
, It
);
1613 if Typ
= Any_Type
then
1614 Error_Msg_N
("designated type does not match specification", P
);
1619 Check_Frozen_Renaming
(N
, New_S
);
1623 end Analyze_Renamed_Dereference
;
1625 ---------------------------
1626 -- Analyze_Renamed_Entry --
1627 ---------------------------
1629 procedure Analyze_Renamed_Entry
1634 Nam
: constant Node_Id
:= Name
(N
);
1635 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1636 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1640 if Entity
(Sel
) = Any_Id
then
1642 -- Selector is undefined on prefix. Error emitted already
1644 Set_Has_Completion
(New_S
);
1648 -- Otherwise find renamed entity and build body of New_S as a call to it
1650 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1652 if Old_S
= Any_Id
then
1653 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1656 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1657 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1658 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1661 -- Only mode conformance required for a renaming_as_declaration
1663 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1666 Inherit_Renamed_Profile
(New_S
, Old_S
);
1668 -- The prefix can be an arbitrary expression that yields a task or
1669 -- protected object, so it must be resolved.
1671 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1674 Set_Convention
(New_S
, Convention
(Old_S
));
1675 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1677 -- AI05-0225: If the renamed entity is a procedure or entry of a
1678 -- protected object, the target object must be a variable.
1680 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1681 and then Ekind
(New_S
) = E_Procedure
1682 and then not Is_Variable
(Prefix
(Nam
))
1686 ("target object of protected operation used as actual for "
1687 & "formal procedure must be a variable", Nam
);
1690 ("target object of protected operation renamed as procedure, "
1691 & "must be a variable", Nam
);
1696 Check_Frozen_Renaming
(N
, New_S
);
1698 end Analyze_Renamed_Entry
;
1700 -----------------------------------
1701 -- Analyze_Renamed_Family_Member --
1702 -----------------------------------
1704 procedure Analyze_Renamed_Family_Member
1709 Nam
: constant Node_Id
:= Name
(N
);
1710 P
: constant Node_Id
:= Prefix
(Nam
);
1714 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1715 or else (Nkind
(P
) = N_Selected_Component
1716 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1718 if Is_Entity_Name
(P
) then
1719 Old_S
:= Entity
(P
);
1721 Old_S
:= Entity
(Selector_Name
(P
));
1724 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1725 Error_Msg_N
("entry family does not match specification", N
);
1728 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1729 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1730 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1734 Error_Msg_N
("no entry family matches specification", N
);
1737 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1740 Check_Frozen_Renaming
(N
, New_S
);
1742 end Analyze_Renamed_Family_Member
;
1744 -----------------------------------------
1745 -- Analyze_Renamed_Primitive_Operation --
1746 -----------------------------------------
1748 procedure Analyze_Renamed_Primitive_Operation
1757 Ctyp
: Conformance_Type
) return Boolean;
1758 -- Verify that the signatures of the renamed entity and the new entity
1759 -- match. The first formal of the renamed entity is skipped because it
1760 -- is the target object in any subsequent call.
1768 Ctyp
: Conformance_Type
) return Boolean
1774 if Ekind
(Subp
) /= Ekind
(New_S
) then
1778 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1779 New_F
:= First_Formal
(New_S
);
1780 while Present
(Old_F
) and then Present
(New_F
) loop
1781 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1785 if Ctyp
>= Mode_Conformant
1786 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1791 Next_Formal
(New_F
);
1792 Next_Formal
(Old_F
);
1798 -- Start of processing for Analyze_Renamed_Primitive_Operation
1801 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1802 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1804 if not Conforms
(Old_S
, Type_Conformant
) then
1809 -- Find the operation that matches the given signature
1817 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1819 while Present
(It
.Nam
) loop
1820 if Conforms
(It
.Nam
, Type_Conformant
) then
1824 Get_Next_Interp
(Ind
, It
);
1829 if Old_S
= Any_Id
then
1830 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1834 if not Conforms
(Old_S
, Subtype_Conformant
) then
1835 Error_Msg_N
("subtype conformance error in renaming", N
);
1838 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1839 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1842 -- Only mode conformance required for a renaming_as_declaration
1844 if not Conforms
(Old_S
, Mode_Conformant
) then
1845 Error_Msg_N
("mode conformance error in renaming", N
);
1848 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1849 -- view of a subprogram is intrinsic, because the compiler has
1850 -- to generate a wrapper for any call to it. If the name in a
1851 -- subprogram renaming is a prefixed view, the entity is thus
1852 -- intrinsic, and 'Access cannot be applied to it.
1854 Set_Convention
(New_S
, Convention_Intrinsic
);
1857 -- Inherit_Renamed_Profile (New_S, Old_S);
1859 -- The prefix can be an arbitrary expression that yields an
1860 -- object, so it must be resolved.
1862 Resolve
(Prefix
(Name
(N
)));
1864 end Analyze_Renamed_Primitive_Operation
;
1866 ---------------------------------
1867 -- Analyze_Subprogram_Renaming --
1868 ---------------------------------
1870 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1871 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1872 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1873 Nam
: constant Node_Id
:= Name
(N
);
1874 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1875 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1876 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1877 Spec
: constant Node_Id
:= Specification
(N
);
1879 Old_S
: Entity_Id
:= Empty
;
1880 Rename_Spec
: Entity_Id
;
1882 procedure Build_Class_Wide_Wrapper
1883 (Ren_Id
: out Entity_Id
;
1884 Wrap_Id
: out Entity_Id
);
1885 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1886 -- type with unknown discriminants and a generic primitive operation of
1887 -- the said type with a box require special processing when the actual
1888 -- is a class-wide type:
1891 -- type Formal_Typ (<>) is private;
1892 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1893 -- package Gen is ...
1895 -- package Inst is new Gen (Actual_Typ'Class);
1897 -- In this case the general renaming mechanism used in the prologue of
1898 -- an instance no longer applies:
1900 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1902 -- The above is replaced the following wrapper/renaming combination:
1904 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1906 -- Prim_Op (Param); -- primitive
1909 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1911 -- This transformation applies only if there is no explicit visible
1912 -- class-wide operation at the point of the instantiation. Ren_Id is
1913 -- the entity of the renaming declaration. Wrap_Id is the entity of
1914 -- the generated class-wide wrapper (or Any_Id).
1916 procedure Check_Null_Exclusion
1919 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1920 -- following AI rules:
1922 -- If Ren is a renaming of a formal subprogram and one of its
1923 -- parameters has a null exclusion, then the corresponding formal
1924 -- in Sub must also have one. Otherwise the subtype of the Sub's
1925 -- formal parameter must exclude null.
1927 -- If Ren is a renaming of a formal function and its return
1928 -- profile has a null exclusion, then Sub's return profile must
1929 -- have one. Otherwise the subtype of Sub's return profile must
1932 procedure Freeze_Actual_Profile
;
1933 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1934 -- types: a callable entity freezes its profile, unless it has an
1935 -- incomplete untagged formal (RM 13.14(10.2/3)).
1937 function Has_Class_Wide_Actual
return Boolean;
1938 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1939 -- defaulted formal subprogram where the actual for the controlling
1940 -- formal type is class-wide.
1942 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1943 -- Find renamed entity when the declaration is a renaming_as_body and
1944 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1945 -- rule that a renaming_as_body is illegal if the declaration occurs
1946 -- before the subprogram it completes is frozen, and renaming indirectly
1947 -- renames the subprogram itself.(Defect Report 8652/0027).
1949 ------------------------------
1950 -- Build_Class_Wide_Wrapper --
1951 ------------------------------
1953 procedure Build_Class_Wide_Wrapper
1954 (Ren_Id
: out Entity_Id
;
1955 Wrap_Id
: out Entity_Id
)
1957 Loc
: constant Source_Ptr
:= Sloc
(N
);
1960 (Subp_Id
: Entity_Id
;
1961 Params
: List_Id
) return Node_Id
;
1962 -- Create a dispatching call to invoke routine Subp_Id with actuals
1963 -- built from the parameter specifications of list Params.
1965 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1966 -- Create a subprogram specification based on the subprogram profile
1969 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1970 -- Find a primitive subprogram of type Typ which matches the profile
1971 -- of the renaming declaration.
1973 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
1974 -- Emit a continuation error message suggesting subprogram Subp_Id as
1975 -- a possible interpretation.
1977 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
1978 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
1981 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
1982 -- Determine whether subprogram Subp_Id is a suitable candidate for
1983 -- the role of a wrapped subprogram.
1990 (Subp_Id
: Entity_Id
;
1991 Params
: List_Id
) return Node_Id
1993 Actuals
: constant List_Id
:= New_List
;
1994 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
1998 -- Build the actual parameters of the call
2000 Formal
:= First
(Params
);
2001 while Present
(Formal
) loop
2003 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2008 -- return Subp_Id (Actuals);
2010 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2012 Make_Simple_Return_Statement
(Loc
,
2014 Make_Function_Call
(Loc
,
2016 Parameter_Associations
=> Actuals
));
2019 -- Subp_Id (Actuals);
2023 Make_Procedure_Call_Statement
(Loc
,
2025 Parameter_Associations
=> Actuals
);
2033 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2034 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2035 Spec_Id
: constant Entity_Id
:=
2036 Make_Defining_Identifier
(Loc
,
2037 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2040 if Ekind
(Formal_Spec
) = E_Procedure
then
2042 Make_Procedure_Specification
(Loc
,
2043 Defining_Unit_Name
=> Spec_Id
,
2044 Parameter_Specifications
=> Params
);
2047 Make_Function_Specification
(Loc
,
2048 Defining_Unit_Name
=> Spec_Id
,
2049 Parameter_Specifications
=> Params
,
2050 Result_Definition
=>
2051 New_Copy_Tree
(Result_Definition
(Spec
)));
2055 --------------------
2056 -- Find_Primitive --
2057 --------------------
2059 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2060 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2061 -- Given a specification Spec, replace all class-wide parameter
2062 -- types with reference to type Typ.
2064 -----------------------------
2065 -- Replace_Parameter_Types --
2066 -----------------------------
2068 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2070 Formal_Id
: Entity_Id
;
2071 Formal_Typ
: Node_Id
;
2074 Formal
:= First
(Parameter_Specifications
(Spec
));
2075 while Present
(Formal
) loop
2076 Formal_Id
:= Defining_Identifier
(Formal
);
2077 Formal_Typ
:= Parameter_Type
(Formal
);
2079 -- Create a new entity for each class-wide formal to prevent
2080 -- aliasing with the original renaming. Replace the type of
2081 -- such a parameter with the candidate type.
2083 if Nkind
(Formal_Typ
) = N_Identifier
2084 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2086 Set_Defining_Identifier
(Formal
,
2087 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2089 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2094 end Replace_Parameter_Types
;
2098 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2099 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2100 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2101 Subp_Id
: Entity_Id
;
2103 -- Start of processing for Find_Primitive
2106 -- Each attempt to find a suitable primitive of a particular type
2107 -- operates on its own copy of the original renaming. As a result
2108 -- the original renaming is kept decoration and side-effect free.
2110 -- Inherit the overloaded status of the renamed subprogram name
2112 if Is_Overloaded
(Nam
) then
2113 Set_Is_Overloaded
(Alt_Nam
);
2114 Save_Interps
(Nam
, Alt_Nam
);
2117 -- The copied renaming is hidden from visibility to prevent the
2118 -- pollution of the enclosing context.
2120 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2122 -- The types of all class-wide parameters must be changed to the
2125 Replace_Parameter_Types
(Alt_Spec
);
2127 -- Try to find a suitable primitive which matches the altered
2128 -- profile of the renaming specification.
2133 Nam
=> Name
(Alt_Ren
),
2134 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2135 Is_Actual
=> Is_Actual
);
2137 -- Do not return Any_Id if the resolion of the altered profile
2138 -- failed as this complicates further checks on the caller side,
2139 -- return Empty instead.
2141 if Subp_Id
= Any_Id
then
2148 --------------------------
2149 -- Interpretation_Error --
2150 --------------------------
2152 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2154 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2156 if Is_Internal
(Subp_Id
) then
2158 ("\\possible interpretation: predefined & #",
2162 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2164 end Interpretation_Error
;
2166 ---------------------------
2167 -- Is_Intrinsic_Equality --
2168 ---------------------------
2170 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2173 Ekind
(Subp_Id
) = E_Operator
2174 and then Chars
(Subp_Id
) = Name_Op_Eq
2175 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2176 end Is_Intrinsic_Equality
;
2178 ---------------------------
2179 -- Is_Suitable_Candidate --
2180 ---------------------------
2182 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2184 if No
(Subp_Id
) then
2187 -- An intrinsic subprogram is never a good candidate. This is an
2188 -- indication of a missing primitive, either defined directly or
2189 -- inherited from a parent tagged type.
2191 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2197 end Is_Suitable_Candidate
;
2201 Actual_Typ
: Entity_Id
:= Empty
;
2202 -- The actual class-wide type for Formal_Typ
2204 CW_Prim_OK
: Boolean;
2205 CW_Prim_Op
: Entity_Id
;
2206 -- The class-wide subprogram (if available) which corresponds to the
2207 -- renamed generic formal subprogram.
2209 Formal_Typ
: Entity_Id
:= Empty
;
2210 -- The generic formal type with unknown discriminants
2212 Root_Prim_OK
: Boolean;
2213 Root_Prim_Op
: Entity_Id
;
2214 -- The root type primitive (if available) which corresponds to the
2215 -- renamed generic formal subprogram.
2217 Root_Typ
: Entity_Id
:= Empty
;
2218 -- The root type of Actual_Typ
2220 Body_Decl
: Node_Id
;
2222 Prim_Op
: Entity_Id
;
2223 Spec_Decl
: Node_Id
;
2225 -- Start of processing for Build_Class_Wide_Wrapper
2228 -- Analyze the specification of the renaming in case the generation
2229 -- of the class-wide wrapper fails.
2231 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2234 -- Do not attempt to build a wrapper if the renaming is in error
2236 if Error_Posted
(Nam
) then
2240 -- Analyze the renamed name, but do not resolve it. The resolution is
2241 -- completed once a suitable subprogram is found.
2245 -- When the renamed name denotes the intrinsic operator equals, the
2246 -- name must be treated as overloaded. This allows for a potential
2247 -- match against the root type's predefined equality function.
2249 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2250 Set_Is_Overloaded
(Nam
);
2251 Collect_Interps
(Nam
);
2254 -- Step 1: Find the generic formal type with unknown discriminants
2255 -- and its corresponding class-wide actual type from the renamed
2256 -- generic formal subprogram.
2258 Formal
:= First_Formal
(Formal_Spec
);
2259 while Present
(Formal
) loop
2260 if Has_Unknown_Discriminants
(Etype
(Formal
))
2261 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2262 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2264 Formal_Typ
:= Etype
(Formal
);
2265 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2266 Root_Typ
:= Etype
(Actual_Typ
);
2270 Next_Formal
(Formal
);
2273 -- The specification of the generic formal subprogram should always
2274 -- contain a formal type with unknown discriminants whose actual is
2275 -- a class-wide type, otherwise this indicates a failure in routine
2276 -- Has_Class_Wide_Actual.
2278 pragma Assert
(Present
(Formal_Typ
));
2280 -- Step 2: Find the proper class-wide subprogram or primitive which
2281 -- corresponds to the renamed generic formal subprogram.
2283 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2284 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2285 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2286 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2288 -- The class-wide actual type has two subprograms which correspond to
2289 -- the renamed generic formal subprogram:
2291 -- with procedure Prim_Op (Param : Formal_Typ);
2293 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2294 -- procedure Prim_Op (Param : Actual_Typ'Class);
2296 -- Even though the declaration of the two subprograms is legal, a
2297 -- call to either one is ambiguous and therefore illegal.
2299 if CW_Prim_OK
and Root_Prim_OK
then
2301 -- A user-defined primitive has precedence over a predefined one
2303 if Is_Internal
(CW_Prim_Op
)
2304 and then not Is_Internal
(Root_Prim_Op
)
2306 Prim_Op
:= Root_Prim_Op
;
2308 elsif Is_Internal
(Root_Prim_Op
)
2309 and then not Is_Internal
(CW_Prim_Op
)
2311 Prim_Op
:= CW_Prim_Op
;
2313 elsif CW_Prim_Op
= Root_Prim_Op
then
2314 Prim_Op
:= Root_Prim_Op
;
2316 -- Otherwise both candidate subprograms are user-defined and
2321 ("ambiguous actual for generic subprogram &",
2323 Interpretation_Error
(Root_Prim_Op
);
2324 Interpretation_Error
(CW_Prim_Op
);
2328 elsif CW_Prim_OK
and not Root_Prim_OK
then
2329 Prim_Op
:= CW_Prim_Op
;
2331 elsif not CW_Prim_OK
and Root_Prim_OK
then
2332 Prim_Op
:= Root_Prim_Op
;
2334 -- An intrinsic equality may act as a suitable candidate in the case
2335 -- of a null type extension where the parent's equality is hidden. A
2336 -- call to an intrinsic equality is expanded as dispatching.
2338 elsif Present
(Root_Prim_Op
)
2339 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2341 Prim_Op
:= Root_Prim_Op
;
2343 -- Otherwise there are no candidate subprograms. Let the caller
2344 -- diagnose the error.
2350 -- At this point resolution has taken place and the name is no longer
2351 -- overloaded. Mark the primitive as referenced.
2353 Set_Is_Overloaded
(Name
(N
), False);
2354 Set_Referenced
(Prim_Op
);
2356 -- Step 3: Create the declaration and the body of the wrapper, insert
2357 -- all the pieces into the tree.
2360 Make_Subprogram_Declaration
(Loc
,
2361 Specification
=> Build_Spec
(Ren_Id
));
2362 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2364 -- If the operator carries an Eliminated pragma, indicate that the
2365 -- wrapper is also to be eliminated, to prevent spurious error when
2366 -- using gnatelim on programs that include box-initialization of
2367 -- equality operators.
2369 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2370 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2373 Make_Subprogram_Body
(Loc
,
2374 Specification
=> Build_Spec
(Ren_Id
),
2375 Declarations
=> New_List
,
2376 Handled_Statement_Sequence
=>
2377 Make_Handled_Sequence_Of_Statements
(Loc
,
2378 Statements
=> New_List
(
2380 (Subp_Id
=> Prim_Op
,
2382 Parameter_Specifications
2383 (Specification
(Spec_Decl
))))));
2385 -- The generated body does not freeze and must be analyzed when the
2386 -- class-wide wrapper is frozen. The body is only needed if expansion
2389 if Expander_Active
then
2390 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2393 -- Step 4: The subprogram renaming aliases the wrapper
2395 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2396 end Build_Class_Wide_Wrapper
;
2398 --------------------------
2399 -- Check_Null_Exclusion --
2400 --------------------------
2402 procedure Check_Null_Exclusion
2406 Ren_Formal
: Entity_Id
;
2407 Sub_Formal
: Entity_Id
;
2412 Ren_Formal
:= First_Formal
(Ren
);
2413 Sub_Formal
:= First_Formal
(Sub
);
2414 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2415 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2417 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2418 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2421 ("`NOT NULL` required for parameter &",
2422 Parent
(Sub_Formal
), Sub_Formal
);
2425 Next_Formal
(Ren_Formal
);
2426 Next_Formal
(Sub_Formal
);
2429 -- Return profile check
2431 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2432 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2433 and then Has_Null_Exclusion
(Parent
(Ren
))
2434 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2435 or else Can_Never_Be_Null
(Etype
(Sub
)))
2438 ("return must specify `NOT NULL`",
2439 Result_Definition
(Parent
(Sub
)));
2441 end Check_Null_Exclusion
;
2443 ---------------------------
2444 -- Freeze_Actual_Profile --
2445 ---------------------------
2447 procedure Freeze_Actual_Profile
is
2449 Has_Untagged_Inc
: Boolean;
2450 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2453 if Ada_Version
>= Ada_2012
then
2454 F
:= First_Formal
(Formal_Spec
);
2455 Has_Untagged_Inc
:= False;
2456 while Present
(F
) loop
2457 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2458 and then not Is_Tagged_Type
(Etype
(F
))
2460 Has_Untagged_Inc
:= True;
2464 F
:= Next_Formal
(F
);
2467 if Ekind
(Formal_Spec
) = E_Function
2468 and then Ekind
(Etype
(Formal_Spec
)) = E_Incomplete_Type
2469 and then not Is_Tagged_Type
(Etype
(F
))
2471 Has_Untagged_Inc
:= True;
2474 if not Has_Untagged_Inc
then
2475 F
:= First_Formal
(Old_S
);
2476 while Present
(F
) loop
2477 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2479 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2480 and then No
(Underlying_Type
(Etype
(F
)))
2482 -- Exclude generic types, or types derived from them.
2483 -- They will be frozen in the enclosing instance.
2485 if Is_Generic_Type
(Etype
(F
))
2486 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2491 ("type& must be frozen before this point",
2492 Instantiation_Node
, Etype
(F
));
2496 F
:= Next_Formal
(F
);
2500 end Freeze_Actual_Profile
;
2502 ---------------------------
2503 -- Has_Class_Wide_Actual --
2504 ---------------------------
2506 function Has_Class_Wide_Actual
return Boolean is
2508 Formal_Typ
: Entity_Id
;
2512 Formal
:= First_Formal
(Formal_Spec
);
2513 while Present
(Formal
) loop
2514 Formal_Typ
:= Etype
(Formal
);
2516 if Has_Unknown_Discriminants
(Formal_Typ
)
2517 and then not Is_Class_Wide_Type
(Formal_Typ
)
2518 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2523 Next_Formal
(Formal
);
2528 end Has_Class_Wide_Actual
;
2530 -------------------------
2531 -- Original_Subprogram --
2532 -------------------------
2534 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2535 Orig_Decl
: Node_Id
;
2536 Orig_Subp
: Entity_Id
;
2539 -- First case: renamed entity is itself a renaming
2541 if Present
(Alias
(Subp
)) then
2542 return Alias
(Subp
);
2544 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2545 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2547 -- Check if renamed entity is a renaming_as_body
2550 Unit_Declaration_Node
2551 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2553 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2554 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2556 if Orig_Subp
= Rename_Spec
then
2558 -- Circularity detected
2563 return (Original_Subprogram
(Orig_Subp
));
2571 end Original_Subprogram
;
2575 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2576 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2577 -- defaulted formal subprogram when the actual for a related formal
2578 -- type is class-wide.
2580 Inst_Node
: Node_Id
:= Empty
;
2583 -- Start of processing for Analyze_Subprogram_Renaming
2586 -- The subprogram renaming declaration may be subject to pragma Ghost
2587 -- with policy Ignore. Set the mode now to ensure that any nodes
2588 -- generated during analysis and expansion are properly flagged as
2593 -- We must test for the attribute renaming case before the Analyze
2594 -- call because otherwise Sem_Attr will complain that the attribute
2595 -- is missing an argument when it is analyzed.
2597 if Nkind
(Nam
) = N_Attribute_Reference
then
2599 -- In the case of an abstract formal subprogram association, rewrite
2600 -- an actual given by a stream attribute as the name of the
2601 -- corresponding stream primitive of the type.
2603 -- In a generic context the stream operations are not generated, and
2604 -- this must be treated as a normal attribute reference, to be
2605 -- expanded in subsequent instantiations.
2608 and then Is_Abstract_Subprogram
(Formal_Spec
)
2609 and then Expander_Active
2612 Stream_Prim
: Entity_Id
;
2613 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2616 -- The class-wide forms of the stream attributes are not
2617 -- primitive dispatching operations (even though they
2618 -- internally dispatch to a stream attribute).
2620 if Is_Class_Wide_Type
(Prefix_Type
) then
2622 ("attribute must be a primitive dispatching operation",
2627 -- Retrieve the primitive subprogram associated with the
2628 -- attribute. This can only be a stream attribute, since those
2629 -- are the only ones that are dispatching (and the actual for
2630 -- an abstract formal subprogram must be dispatching
2634 case Attribute_Name
(Nam
) is
2637 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2640 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2643 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2646 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2649 ("attribute must be a primitive"
2650 & " dispatching operation", Nam
);
2656 -- If no operation was found, and the type is limited,
2657 -- the user should have defined one.
2659 when Program_Error
=>
2660 if Is_Limited_Type
(Prefix_Type
) then
2662 ("stream operation not defined for type&",
2666 -- Otherwise, compiler should have generated default
2673 -- Rewrite the attribute into the name of its corresponding
2674 -- primitive dispatching subprogram. We can then proceed with
2675 -- the usual processing for subprogram renamings.
2678 Prim_Name
: constant Node_Id
:=
2679 Make_Identifier
(Sloc
(Nam
),
2680 Chars
=> Chars
(Stream_Prim
));
2682 Set_Entity
(Prim_Name
, Stream_Prim
);
2683 Rewrite
(Nam
, Prim_Name
);
2688 -- Normal processing for a renaming of an attribute
2691 Attribute_Renaming
(N
);
2696 -- Check whether this declaration corresponds to the instantiation
2697 -- of a formal subprogram.
2699 -- If this is an instantiation, the corresponding actual is frozen and
2700 -- error messages can be made more precise. If this is a default
2701 -- subprogram, the entity is already established in the generic, and is
2702 -- not retrieved by visibility. If it is a default with a box, the
2703 -- candidate interpretations, if any, have been collected when building
2704 -- the renaming declaration. If overloaded, the proper interpretation is
2705 -- determined in Find_Renamed_Entity. If the entity is an operator,
2706 -- Find_Renamed_Entity applies additional visibility checks.
2709 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2711 -- Check whether the renaming is for a defaulted actual subprogram
2712 -- with a class-wide actual.
2714 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2715 -- is an external axiomatization on the package.
2718 and then Box_Present
(Inst_Node
)
2722 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2724 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2726 elsif Is_Entity_Name
(Nam
)
2727 and then Present
(Entity
(Nam
))
2728 and then not Comes_From_Source
(Nam
)
2729 and then not Is_Overloaded
(Nam
)
2731 Old_S
:= Entity
(Nam
);
2732 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2736 if Ekind
(Entity
(Nam
)) = E_Operator
then
2740 if Box_Present
(Inst_Node
) then
2741 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2743 -- If there is an immediately visible homonym of the operator
2744 -- and the declaration has a default, this is worth a warning
2745 -- because the user probably did not intend to get the pre-
2746 -- defined operator, visible in the generic declaration. To
2747 -- find if there is an intended candidate, analyze the renaming
2748 -- again in the current context.
2750 elsif Scope
(Old_S
) = Standard_Standard
2751 and then Present
(Default_Name
(Inst_Node
))
2754 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2758 Set_Entity
(Name
(Decl
), Empty
);
2759 Analyze
(Name
(Decl
));
2761 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2764 and then In_Open_Scopes
(Scope
(Hidden
))
2765 and then Is_Immediately_Visible
(Hidden
)
2766 and then Comes_From_Source
(Hidden
)
2767 and then Hidden
/= Old_S
2769 Error_Msg_Sloc
:= Sloc
(Hidden
);
2770 Error_Msg_N
("default subprogram is resolved " &
2771 "in the generic declaration " &
2772 "(RM 12.6(17))??", N
);
2773 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2781 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2785 -- Renamed entity must be analyzed first, to avoid being hidden by
2786 -- new name (which might be the same in a generic instance).
2790 -- The renaming defines a new overloaded entity, which is analyzed
2791 -- like a subprogram declaration.
2793 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2796 if Current_Scope
/= Standard_Standard
then
2797 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2800 -- Set SPARK mode from current context
2802 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2803 Set_SPARK_Pragma_Inherited
(New_S
, True);
2805 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2807 -- Case of Renaming_As_Body
2809 if Present
(Rename_Spec
) then
2811 -- Renaming declaration is the completion of the declaration of
2812 -- Rename_Spec. We build an actual body for it at the freezing point.
2814 Set_Corresponding_Spec
(N
, Rename_Spec
);
2816 -- Deal with special case of stream functions of abstract types
2819 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2820 N_Abstract_Subprogram_Declaration
2822 -- Input stream functions are abstract if the object type is
2823 -- abstract. Similarly, all default stream functions for an
2824 -- interface type are abstract. However, these subprograms may
2825 -- receive explicit declarations in representation clauses, making
2826 -- the attribute subprograms usable as defaults in subsequent
2828 -- In this case we rewrite the declaration to make the subprogram
2829 -- non-abstract. We remove the previous declaration, and insert
2830 -- the new one at the point of the renaming, to prevent premature
2831 -- access to unfrozen types. The new declaration reuses the
2832 -- specification of the previous one, and must not be analyzed.
2835 (Is_Primitive
(Entity
(Nam
))
2837 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2839 Old_Decl
: constant Node_Id
:=
2840 Unit_Declaration_Node
(Rename_Spec
);
2841 New_Decl
: constant Node_Id
:=
2842 Make_Subprogram_Declaration
(Sloc
(N
),
2844 Relocate_Node
(Specification
(Old_Decl
)));
2847 Insert_After
(N
, New_Decl
);
2848 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2849 Set_Analyzed
(New_Decl
);
2853 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2855 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2856 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2859 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2860 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2861 Set_Public_Status
(New_S
);
2863 -- The specification does not introduce new formals, but only
2864 -- repeats the formals of the original subprogram declaration.
2865 -- For cross-reference purposes, and for refactoring tools, we
2866 -- treat the formals of the renaming declaration as body formals.
2868 Reference_Body_Formals
(Rename_Spec
, New_S
);
2870 -- Indicate that the entity in the declaration functions like the
2871 -- corresponding body, and is not a new entity. The body will be
2872 -- constructed later at the freeze point, so indicate that the
2873 -- completion has not been seen yet.
2875 Set_Ekind
(New_S
, E_Subprogram_Body
);
2876 New_S
:= Rename_Spec
;
2877 Set_Has_Completion
(Rename_Spec
, False);
2879 -- Ada 2005: check overriding indicator
2881 if Present
(Overridden_Operation
(Rename_Spec
)) then
2882 if Must_Not_Override
(Specification
(N
)) then
2884 ("subprogram& overrides inherited operation",
2887 Style_Check
and then not Must_Override
(Specification
(N
))
2889 Style
.Missing_Overriding
(N
, Rename_Spec
);
2892 elsif Must_Override
(Specification
(N
)) then
2893 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2896 -- Normal subprogram renaming (not renaming as body)
2899 Generate_Definition
(New_S
);
2900 New_Overloaded_Entity
(New_S
);
2902 if Is_Entity_Name
(Nam
)
2903 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2907 Check_Delayed_Subprogram
(New_S
);
2911 -- There is no need for elaboration checks on the new entity, which may
2912 -- be called before the next freezing point where the body will appear.
2913 -- Elaboration checks refer to the real entity, not the one created by
2914 -- the renaming declaration.
2916 Set_Kill_Elaboration_Checks
(New_S
, True);
2918 -- If we had a previous error, indicate a completely is present to stop
2919 -- junk cascaded messages, but don't take any further action.
2921 if Etype
(Nam
) = Any_Type
then
2922 Set_Has_Completion
(New_S
);
2925 -- Case where name has the form of a selected component
2927 elsif Nkind
(Nam
) = N_Selected_Component
then
2929 -- A name which has the form A.B can designate an entry of task A, a
2930 -- protected operation of protected object A, or finally a primitive
2931 -- operation of object A. In the later case, A is an object of some
2932 -- tagged type, or an access type that denotes one such. To further
2933 -- distinguish these cases, note that the scope of a task entry or
2934 -- protected operation is type of the prefix.
2936 -- The prefix could be an overloaded function call that returns both
2937 -- kinds of operations. This overloading pathology is left to the
2938 -- dedicated reader ???
2941 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2949 and then Is_Tagged_Type
(Designated_Type
(T
))))
2950 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2952 Analyze_Renamed_Primitive_Operation
2953 (N
, New_S
, Present
(Rename_Spec
));
2957 -- Renamed entity is an entry or protected operation. For those
2958 -- cases an explicit body is built (at the point of freezing of
2959 -- this entity) that contains a call to the renamed entity.
2961 -- This is not allowed for renaming as body if the renamed
2962 -- spec is already frozen (see RM 8.5.4(5) for details).
2964 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
2966 ("renaming-as-body cannot rename entry as subprogram", N
);
2968 ("\since & is already frozen (RM 8.5.4(5))",
2971 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
2978 -- Case where name is an explicit dereference X.all
2980 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
2982 -- Renamed entity is designated by access_to_subprogram expression.
2983 -- Must build body to encapsulate call, as in the entry case.
2985 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
2988 -- Indexed component
2990 elsif Nkind
(Nam
) = N_Indexed_Component
then
2991 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
2994 -- Character literal
2996 elsif Nkind
(Nam
) = N_Character_Literal
then
2997 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
3000 -- Only remaining case is where we have a non-entity name, or a renaming
3001 -- of some other non-overloadable entity.
3003 elsif not Is_Entity_Name
(Nam
)
3004 or else not Is_Overloadable
(Entity
(Nam
))
3006 -- Do not mention the renaming if it comes from an instance
3008 if not Is_Actual
then
3009 Error_Msg_N
("expect valid subprogram name in renaming", N
);
3011 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3017 -- Find the renamed entity that matches the given specification. Disable
3018 -- Ada_83 because there is no requirement of full conformance between
3019 -- renamed entity and new entity, even though the same circuit is used.
3021 -- This is a bit of an odd case, which introduces a really irregular use
3022 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3025 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3026 Ada_Version_Pragma
:= Empty
;
3027 Ada_Version_Explicit
:= Ada_Version
;
3030 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3032 -- The visible operation may be an inherited abstract operation that
3033 -- was overridden in the private part, in which case a call will
3034 -- dispatch to the overriding operation. Use the overriding one in
3035 -- the renaming declaration, to prevent spurious errors below.
3037 if Is_Overloadable
(Old_S
)
3038 and then Is_Abstract_Subprogram
(Old_S
)
3039 and then No
(DTC_Entity
(Old_S
))
3040 and then Present
(Alias
(Old_S
))
3041 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3042 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3044 Old_S
:= Alias
(Old_S
);
3047 -- When the renamed subprogram is overloaded and used as an actual
3048 -- of a generic, its entity is set to the first available homonym.
3049 -- We must first disambiguate the name, then set the proper entity.
3051 if Is_Actual
and then Is_Overloaded
(Nam
) then
3052 Set_Entity
(Nam
, Old_S
);
3056 -- Most common case: subprogram renames subprogram. No body is generated
3057 -- in this case, so we must indicate the declaration is complete as is.
3058 -- and inherit various attributes of the renamed subprogram.
3060 if No
(Rename_Spec
) then
3061 Set_Has_Completion
(New_S
);
3062 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3063 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3064 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3066 -- A subprogram renaming is Ghost if the renamed entity is Ghost or
3067 -- the construct appears within a Ghost scope.
3069 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
3070 Set_Is_Ghost_Entity
(New_S
);
3073 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3074 -- between a subprogram and its correct renaming.
3076 -- Note: the Any_Id check is a guard that prevents compiler crashes
3077 -- when performing a null exclusion check between a renaming and a
3078 -- renamed subprogram that has been found to be illegal.
3080 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3081 Check_Null_Exclusion
3083 Sub
=> Entity
(Nam
));
3086 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3087 -- overriding. The flag Requires_Overriding is set very selectively
3088 -- and misses some other illegal cases. The additional conditions
3089 -- checked below are sufficient but not necessary ???
3091 -- The rule does not apply to the renaming generated for an actual
3092 -- subprogram in an instance.
3097 -- Guard against previous errors, and omit renamings of predefined
3100 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3103 elsif Requires_Overriding
(Old_S
)
3105 (Is_Abstract_Subprogram
(Old_S
)
3106 and then Present
(Find_Dispatching_Type
(Old_S
))
3108 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3111 ("renamed entity cannot be "
3112 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3116 if Old_S
/= Any_Id
then
3117 if Is_Actual
and then From_Default
(N
) then
3119 -- This is an implicit reference to the default actual
3121 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3124 Generate_Reference
(Old_S
, Nam
);
3127 Check_Internal_Protected_Use
(N
, Old_S
);
3129 -- For a renaming-as-body, require subtype conformance, but if the
3130 -- declaration being completed has not been frozen, then inherit the
3131 -- convention of the renamed subprogram prior to checking conformance
3132 -- (unless the renaming has an explicit convention established; the
3133 -- rule stated in the RM doesn't seem to address this ???).
3135 if Present
(Rename_Spec
) then
3136 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3137 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3139 if not Is_Frozen
(Rename_Spec
) then
3140 if not Has_Convention_Pragma
(Rename_Spec
) then
3141 Set_Convention
(New_S
, Convention
(Old_S
));
3144 if Ekind
(Old_S
) /= E_Operator
then
3145 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3148 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3149 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3152 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3155 Check_Frozen_Renaming
(N
, Rename_Spec
);
3157 -- Check explicitly that renamed entity is not intrinsic, because
3158 -- in a generic the renamed body is not built. In this case,
3159 -- the renaming_as_body is a completion.
3161 if Inside_A_Generic
then
3162 if Is_Frozen
(Rename_Spec
)
3163 and then Is_Intrinsic_Subprogram
(Old_S
)
3166 ("subprogram in renaming_as_body cannot be intrinsic",
3170 Set_Has_Completion
(Rename_Spec
);
3173 elsif Ekind
(Old_S
) /= E_Operator
then
3175 -- If this a defaulted subprogram for a class-wide actual there is
3176 -- no check for mode conformance, given that the signatures don't
3177 -- match (the source mentions T but the actual mentions T'Class).
3181 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3182 Check_Mode_Conformant
(New_S
, Old_S
);
3185 if Is_Actual
and then Error_Posted
(New_S
) then
3186 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3190 if No
(Rename_Spec
) then
3192 -- The parameter profile of the new entity is that of the renamed
3193 -- entity: the subtypes given in the specification are irrelevant.
3195 Inherit_Renamed_Profile
(New_S
, Old_S
);
3197 -- A call to the subprogram is transformed into a call to the
3198 -- renamed entity. This is transitive if the renamed entity is
3199 -- itself a renaming.
3201 if Present
(Alias
(Old_S
)) then
3202 Set_Alias
(New_S
, Alias
(Old_S
));
3204 Set_Alias
(New_S
, Old_S
);
3207 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3208 -- renaming as body, since the entity in this case is not an
3209 -- intrinsic (it calls an intrinsic, but we have a real body for
3210 -- this call, and it is in this body that the required intrinsic
3211 -- processing will take place).
3213 -- Also, if this is a renaming of inequality, the renamed operator
3214 -- is intrinsic, but what matters is the corresponding equality
3215 -- operator, which may be user-defined.
3217 Set_Is_Intrinsic_Subprogram
3219 Is_Intrinsic_Subprogram
(Old_S
)
3221 (Chars
(Old_S
) /= Name_Op_Ne
3222 or else Ekind
(Old_S
) = E_Operator
3223 or else Is_Intrinsic_Subprogram
3224 (Corresponding_Equality
(Old_S
))));
3226 if Ekind
(Alias
(New_S
)) = E_Operator
then
3227 Set_Has_Delayed_Freeze
(New_S
, False);
3230 -- If the renaming corresponds to an association for an abstract
3231 -- formal subprogram, then various attributes must be set to
3232 -- indicate that the renaming is an abstract dispatching operation
3233 -- with a controlling type.
3235 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3237 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3238 -- see it as corresponding to a generic association for a
3239 -- formal abstract subprogram
3241 Set_Is_Abstract_Subprogram
(New_S
);
3244 New_S_Ctrl_Type
: constant Entity_Id
:=
3245 Find_Dispatching_Type
(New_S
);
3246 Old_S_Ctrl_Type
: constant Entity_Id
:=
3247 Find_Dispatching_Type
(Old_S
);
3250 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
3252 ("actual must be dispatching subprogram for type&",
3253 Nam
, New_S_Ctrl_Type
);
3256 Set_Is_Dispatching_Operation
(New_S
);
3257 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3259 -- If the actual in the formal subprogram is itself a
3260 -- formal abstract subprogram association, there's no
3261 -- dispatch table component or position to inherit.
3263 if Present
(DTC_Entity
(Old_S
)) then
3264 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3265 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3275 -- The following is illegal, because F hides whatever other F may
3277 -- function F (...) renames F;
3280 or else (Nkind
(Nam
) /= N_Expanded_Name
3281 and then Chars
(Old_S
) = Chars
(New_S
))
3283 Error_Msg_N
("subprogram cannot rename itself", N
);
3285 -- This is illegal even if we use a selector:
3286 -- function F (...) renames Pkg.F;
3287 -- because F is still hidden.
3289 elsif Nkind
(Nam
) = N_Expanded_Name
3290 and then Entity
(Prefix
(Nam
)) = Current_Scope
3291 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3293 -- This is an error, but we overlook the error and accept the
3294 -- renaming if the special Overriding_Renamings mode is in effect.
3296 if not Overriding_Renamings
then
3298 ("implicit operation& is not visible (RM 8.3 (15))",
3303 Set_Convention
(New_S
, Convention
(Old_S
));
3305 if Is_Abstract_Subprogram
(Old_S
) then
3306 if Present
(Rename_Spec
) then
3308 ("a renaming-as-body cannot rename an abstract subprogram",
3310 Set_Has_Completion
(Rename_Spec
);
3312 Set_Is_Abstract_Subprogram
(New_S
);
3316 Check_Library_Unit_Renaming
(N
, Old_S
);
3318 -- Pathological case: procedure renames entry in the scope of its
3319 -- task. Entry is given by simple name, but body must be built for
3320 -- procedure. Of course if called it will deadlock.
3322 if Ekind
(Old_S
) = E_Entry
then
3323 Set_Has_Completion
(New_S
, False);
3324 Set_Alias
(New_S
, Empty
);
3328 Freeze_Before
(N
, Old_S
);
3329 Freeze_Actual_Profile
;
3330 Set_Has_Delayed_Freeze
(New_S
, False);
3331 Freeze_Before
(N
, New_S
);
3333 -- An abstract subprogram is only allowed as an actual in the case
3334 -- where the formal subprogram is also abstract.
3336 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3337 and then Is_Abstract_Subprogram
(Old_S
)
3338 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3341 ("abstract subprogram not allowed as generic actual", Nam
);
3346 -- A common error is to assume that implicit operators for types are
3347 -- defined in Standard, or in the scope of a subtype. In those cases
3348 -- where the renamed entity is given with an expanded name, it is
3349 -- worth mentioning that operators for the type are not declared in
3350 -- the scope given by the prefix.
3352 if Nkind
(Nam
) = N_Expanded_Name
3353 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3354 and then Scope
(Entity
(Nam
)) = Standard_Standard
3357 T
: constant Entity_Id
:=
3358 Base_Type
(Etype
(First_Formal
(New_S
)));
3360 Error_Msg_Node_2
:= Prefix
(Nam
);
3362 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3367 ("no visible subprogram matches the specification for&",
3371 if Present
(Candidate_Renaming
) then
3378 F1
:= First_Formal
(Candidate_Renaming
);
3379 F2
:= First_Formal
(New_S
);
3380 T1
:= First_Subtype
(Etype
(F1
));
3381 while Present
(F1
) and then Present
(F2
) loop
3386 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3387 if Present
(Next_Formal
(F1
)) then
3389 ("\missing specification for &" &
3390 " and other formals with defaults", Spec
, F1
);
3393 ("\missing specification for &", Spec
, F1
);
3397 if Nkind
(Nam
) = N_Operator_Symbol
3398 and then From_Default
(N
)
3400 Error_Msg_Node_2
:= T1
;
3402 ("default & on & is not directly visible",
3409 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3410 -- controlling access parameters are known non-null for the renamed
3411 -- subprogram. Test also applies to a subprogram instantiation that
3412 -- is dispatching. Test is skipped if some previous error was detected
3413 -- that set Old_S to Any_Id.
3415 if Ada_Version
>= Ada_2005
3416 and then Old_S
/= Any_Id
3417 and then not Is_Dispatching_Operation
(Old_S
)
3418 and then Is_Dispatching_Operation
(New_S
)
3425 Old_F
:= First_Formal
(Old_S
);
3426 New_F
:= First_Formal
(New_S
);
3427 while Present
(Old_F
) loop
3428 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3429 and then Is_Controlling_Formal
(New_F
)
3430 and then not Can_Never_Be_Null
(Old_F
)
3432 Error_Msg_N
("access parameter is controlling,", New_F
);
3434 ("\corresponding parameter of& "
3435 & "must be explicitly null excluding", New_F
, Old_S
);
3438 Next_Formal
(Old_F
);
3439 Next_Formal
(New_F
);
3444 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3445 -- is to warn if an operator is being renamed as a different operator.
3446 -- If the operator is predefined, examine the kind of the entity, not
3447 -- the abbreviated declaration in Standard.
3449 if Comes_From_Source
(N
)
3450 and then Present
(Old_S
)
3451 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3452 or else Ekind
(Old_S
) = E_Operator
)
3453 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3454 and then Chars
(Old_S
) /= Chars
(New_S
)
3457 ("& is being renamed as a different operator??", N
, Old_S
);
3460 -- Check for renaming of obsolescent subprogram
3462 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3464 -- Another warning or some utility: if the new subprogram as the same
3465 -- name as the old one, the old one is not hidden by an outer homograph,
3466 -- the new one is not a public symbol, and the old one is otherwise
3467 -- directly visible, the renaming is superfluous.
3469 if Chars
(Old_S
) = Chars
(New_S
)
3470 and then Comes_From_Source
(N
)
3471 and then Scope
(Old_S
) /= Standard_Standard
3472 and then Warn_On_Redundant_Constructs
3473 and then (Is_Immediately_Visible
(Old_S
)
3474 or else Is_Potentially_Use_Visible
(Old_S
))
3475 and then Is_Overloadable
(Current_Scope
)
3476 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3479 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3482 -- Implementation-defined aspect specifications can appear in a renaming
3483 -- declaration, but not language-defined ones. The call to procedure
3484 -- Analyze_Aspect_Specifications will take care of this error check.
3486 if Has_Aspects
(N
) then
3487 Analyze_Aspect_Specifications
(N
, New_S
);
3490 Ada_Version
:= Save_AV
;
3491 Ada_Version_Pragma
:= Save_AVP
;
3492 Ada_Version_Explicit
:= Save_AV_Exp
;
3494 -- In GNATprove mode, the renamings of actual subprograms are replaced
3495 -- with wrapper functions that make it easier to propagate axioms to the
3496 -- points of call within an instance. Wrappers are generated if formal
3497 -- subprogram is subject to axiomatization.
3499 -- The types in the wrapper profiles are obtained from (instances of)
3500 -- the types of the formal subprogram.
3503 and then GNATprove_Mode
3504 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3505 and then not Inside_A_Generic
3507 if Ekind
(Old_S
) = E_Function
then
3508 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3511 elsif Ekind
(Old_S
) = E_Operator
then
3512 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3516 end Analyze_Subprogram_Renaming
;
3518 -------------------------
3519 -- Analyze_Use_Package --
3520 -------------------------
3522 -- Resolve the package names in the use clause, and make all the visible
3523 -- entities defined in the package potentially use-visible. If the package
3524 -- is already in use from a previous use clause, its visible entities are
3525 -- already use-visible. In that case, mark the occurrence as a redundant
3526 -- use. If the package is an open scope, i.e. if the use clause occurs
3527 -- within the package itself, ignore it.
3529 procedure Analyze_Use_Package
(N
: Node_Id
) is
3530 Pack_Name
: Node_Id
;
3533 -- Start of processing for Analyze_Use_Package
3536 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3538 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3540 -- Use clause not allowed in a spec of a predefined package declaration
3541 -- except that packages whose file name starts a-n are OK (these are
3542 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3544 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3545 and then Name_Buffer
(1 .. 3) /= "a-n"
3547 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3549 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3552 -- Chain clause to list of use clauses in current scope
3554 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3555 Chain_Use_Clause
(N
);
3558 -- Loop through package names to identify referenced packages
3560 Pack_Name
:= First
(Names
(N
));
3561 while Present
(Pack_Name
) loop
3562 Analyze
(Pack_Name
);
3564 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3565 and then Nkind
(Pack_Name
) = N_Expanded_Name
3571 Pref
:= Prefix
(Pack_Name
);
3572 while Nkind
(Pref
) = N_Expanded_Name
loop
3573 Pref
:= Prefix
(Pref
);
3576 if Entity
(Pref
) = Standard_Standard
then
3578 ("predefined package Standard cannot appear"
3579 & " in a context clause", Pref
);
3587 -- Loop through package names to mark all entities as potentially
3590 Pack_Name
:= First
(Names
(N
));
3591 while Present
(Pack_Name
) loop
3592 if Is_Entity_Name
(Pack_Name
) then
3593 Pack
:= Entity
(Pack_Name
);
3595 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3596 if Ekind
(Pack
) = E_Generic_Package
then
3597 Error_Msg_N
-- CODEFIX
3598 ("a generic package is not allowed in a use clause",
3601 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3603 Error_Msg_N
-- CODEFIX
3604 ("a generic subprogram is not allowed in a use clause",
3607 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3608 Error_Msg_N
-- CODEFIX
3609 ("a subprogram is not allowed in a use clause",
3613 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3617 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3618 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3621 if Applicable_Use
(Pack_Name
) then
3622 Use_One_Package
(Pack
, N
);
3626 -- Report error because name denotes something other than a package
3629 Error_Msg_N
("& is not a package", Pack_Name
);
3634 end Analyze_Use_Package
;
3636 ----------------------
3637 -- Analyze_Use_Type --
3638 ----------------------
3640 procedure Analyze_Use_Type
(N
: Node_Id
) is
3645 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3647 -- Chain clause to list of use clauses in current scope
3649 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3650 Chain_Use_Clause
(N
);
3653 -- If the Used_Operations list is already initialized, the clause has
3654 -- been analyzed previously, and it is begin reinstalled, for example
3655 -- when the clause appears in a package spec and we are compiling the
3656 -- corresponding package body. In that case, make the entities on the
3657 -- existing list use_visible, and mark the corresponding types In_Use.
3659 if Present
(Used_Operations
(N
)) then
3665 Mark
:= First
(Subtype_Marks
(N
));
3666 while Present
(Mark
) loop
3667 Use_One_Type
(Mark
, Installed
=> True);
3671 Elmt
:= First_Elmt
(Used_Operations
(N
));
3672 while Present
(Elmt
) loop
3673 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3681 -- Otherwise, create new list and attach to it the operations that
3682 -- are made use-visible by the clause.
3684 Set_Used_Operations
(N
, New_Elmt_List
);
3685 Id
:= First
(Subtype_Marks
(N
));
3686 while Present
(Id
) loop
3690 if E
/= Any_Type
then
3693 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3694 if Nkind
(Id
) = N_Identifier
then
3695 Error_Msg_N
("type is not directly visible", Id
);
3697 elsif Is_Child_Unit
(Scope
(E
))
3698 and then Scope
(E
) /= System_Aux_Id
3700 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3705 -- If the use_type_clause appears in a compilation unit context,
3706 -- check whether it comes from a unit that may appear in a
3707 -- limited_with_clause, for a better error message.
3709 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3710 and then Nkind
(Id
) /= N_Identifier
3716 function Mentioned
(Nam
: Node_Id
) return Boolean;
3717 -- Check whether the prefix of expanded name for the type
3718 -- appears in the prefix of some limited_with_clause.
3724 function Mentioned
(Nam
: Node_Id
) return Boolean is
3726 return Nkind
(Name
(Item
)) = N_Selected_Component
3727 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3731 Pref
:= Prefix
(Id
);
3732 Item
:= First
(Context_Items
(Parent
(N
)));
3733 while Present
(Item
) and then Item
/= N
loop
3734 if Nkind
(Item
) = N_With_Clause
3735 and then Limited_Present
(Item
)
3736 and then Mentioned
(Pref
)
3739 (Get_Msg_Id
, "premature usage of incomplete type");
3750 end Analyze_Use_Type
;
3752 --------------------
3753 -- Applicable_Use --
3754 --------------------
3756 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3757 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3760 if In_Open_Scopes
(Pack
) then
3761 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3762 Error_Msg_NE
-- CODEFIX
3763 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3768 elsif In_Use
(Pack
) then
3769 Note_Redundant_Use
(Pack_Name
);
3772 elsif Present
(Renamed_Object
(Pack
))
3773 and then In_Use
(Renamed_Object
(Pack
))
3775 Note_Redundant_Use
(Pack_Name
);
3783 ------------------------
3784 -- Attribute_Renaming --
3785 ------------------------
3787 procedure Attribute_Renaming
(N
: Node_Id
) is
3788 Loc
: constant Source_Ptr
:= Sloc
(N
);
3789 Nam
: constant Node_Id
:= Name
(N
);
3790 Spec
: constant Node_Id
:= Specification
(N
);
3791 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3792 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3794 Form_Num
: Nat
:= 0;
3795 Expr_List
: List_Id
:= No_List
;
3797 Attr_Node
: Node_Id
;
3798 Body_Node
: Node_Id
;
3799 Param_Spec
: Node_Id
;
3802 Generate_Definition
(New_S
);
3804 -- This procedure is called in the context of subprogram renaming, and
3805 -- thus the attribute must be one that is a subprogram. All of those
3806 -- have at least one formal parameter, with the exceptions of the GNAT
3807 -- attribute 'Img, which GNAT treats as renameable.
3809 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3810 if Aname
/= Name_Img
then
3812 ("subprogram renaming an attribute must have formals", N
);
3817 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3818 while Present
(Param_Spec
) loop
3819 Form_Num
:= Form_Num
+ 1;
3821 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3822 Find_Type
(Parameter_Type
(Param_Spec
));
3824 -- The profile of the new entity denotes the base type (s) of
3825 -- the types given in the specification. For access parameters
3826 -- there are no subtypes involved.
3828 Rewrite
(Parameter_Type
(Param_Spec
),
3830 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3833 if No
(Expr_List
) then
3834 Expr_List
:= New_List
;
3837 Append_To
(Expr_List
,
3838 Make_Identifier
(Loc
,
3839 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3841 -- The expressions in the attribute reference are not freeze
3842 -- points. Neither is the attribute as a whole, see below.
3844 Set_Must_Not_Freeze
(Last
(Expr_List
));
3849 -- Immediate error if too many formals. Other mismatches in number or
3850 -- types of parameters are detected when we analyze the body of the
3851 -- subprogram that we construct.
3853 if Form_Num
> 2 then
3854 Error_Msg_N
("too many formals for attribute", N
);
3856 -- Error if the attribute reference has expressions that look like
3857 -- formal parameters.
3859 elsif Present
(Expressions
(Nam
)) then
3860 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3863 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3864 Name_Pos
, Name_Round
, Name_Scaling
,
3867 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3868 and then Present
(Corresponding_Formal_Spec
(N
))
3871 ("generic actual cannot be attribute involving universal type",
3875 ("attribute involving a universal type cannot be renamed",
3880 -- Rewrite attribute node to have a list of expressions corresponding to
3881 -- the subprogram formals. A renaming declaration is not a freeze point,
3882 -- and the analysis of the attribute reference should not freeze the
3883 -- type of the prefix. We use the original node in the renaming so that
3884 -- its source location is preserved, and checks on stream attributes are
3885 -- properly applied.
3887 Attr_Node
:= Relocate_Node
(Nam
);
3888 Set_Expressions
(Attr_Node
, Expr_List
);
3890 Set_Must_Not_Freeze
(Attr_Node
);
3891 Set_Must_Not_Freeze
(Prefix
(Nam
));
3893 -- Case of renaming a function
3895 if Nkind
(Spec
) = N_Function_Specification
then
3896 if Is_Procedure_Attribute_Name
(Aname
) then
3897 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3901 Find_Type
(Result_Definition
(Spec
));
3902 Rewrite
(Result_Definition
(Spec
),
3904 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3907 Make_Subprogram_Body
(Loc
,
3908 Specification
=> Spec
,
3909 Declarations
=> New_List
,
3910 Handled_Statement_Sequence
=>
3911 Make_Handled_Sequence_Of_Statements
(Loc
,
3912 Statements
=> New_List
(
3913 Make_Simple_Return_Statement
(Loc
,
3914 Expression
=> Attr_Node
))));
3916 -- Case of renaming a procedure
3919 if not Is_Procedure_Attribute_Name
(Aname
) then
3920 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3925 Make_Subprogram_Body
(Loc
,
3926 Specification
=> Spec
,
3927 Declarations
=> New_List
,
3928 Handled_Statement_Sequence
=>
3929 Make_Handled_Sequence_Of_Statements
(Loc
,
3930 Statements
=> New_List
(Attr_Node
)));
3933 -- In case of tagged types we add the body of the generated function to
3934 -- the freezing actions of the type (because in the general case such
3935 -- type is still not frozen). We exclude from this processing generic
3936 -- formal subprograms found in instantiations.
3938 -- We must exclude VM targets and restricted run-time libraries because
3939 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3940 -- available in those platforms. Note that we cannot use the function
3941 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3942 -- the ZFP run-time library is not defined as a profile, and we do not
3943 -- want to deal with AST_Handler in ZFP mode.
3945 if VM_Target
= No_VM
3946 and then not Configurable_Run_Time_Mode
3947 and then not Present
(Corresponding_Formal_Spec
(N
))
3948 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
3951 P
: constant Node_Id
:= Prefix
(Nam
);
3954 -- The prefix of 'Img is an object that is evaluated for each call
3955 -- of the function that renames it.
3957 if Aname
= Name_Img
then
3958 Preanalyze_And_Resolve
(P
);
3960 -- For all other attribute renamings, the prefix is a subtype
3966 -- If the target type is not yet frozen, add the body to the
3967 -- actions to be elaborated at freeze time.
3969 if Is_Tagged_Type
(Etype
(P
))
3970 and then In_Open_Scopes
(Scope
(Etype
(P
)))
3972 Ensure_Freeze_Node
(Etype
(P
));
3973 Append_Freeze_Action
(Etype
(P
), Body_Node
);
3975 Rewrite
(N
, Body_Node
);
3977 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3981 -- Generic formal subprograms or AST_Handler renaming
3984 Rewrite
(N
, Body_Node
);
3986 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3989 if Is_Compilation_Unit
(New_S
) then
3991 ("a library unit can only rename another library unit", N
);
3994 -- We suppress elaboration warnings for the resulting entity, since
3995 -- clearly they are not needed, and more particularly, in the case
3996 -- of a generic formal subprogram, the resulting entity can appear
3997 -- after the instantiation itself, and thus look like a bogus case
3998 -- of access before elaboration.
4000 Set_Suppress_Elaboration_Warnings
(New_S
);
4002 end Attribute_Renaming
;
4004 ----------------------
4005 -- Chain_Use_Clause --
4006 ----------------------
4008 procedure Chain_Use_Clause
(N
: Node_Id
) is
4010 Level
: Int
:= Scope_Stack
.Last
;
4013 if not Is_Compilation_Unit
(Current_Scope
)
4014 or else not Is_Child_Unit
(Current_Scope
)
4016 null; -- Common case
4018 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
4019 null; -- Common case for compilation unit
4022 -- If declaration appears in some other scope, it must be in some
4023 -- parent unit when compiling a child.
4025 Pack
:= Defining_Entity
(Parent
(N
));
4026 if not In_Open_Scopes
(Pack
) then
4027 null; -- default as well
4029 -- If the use clause appears in an ancestor and we are in the
4030 -- private part of the immediate parent, the use clauses are
4031 -- already installed.
4033 elsif Pack
/= Scope
(Current_Scope
)
4034 and then In_Private_Part
(Scope
(Current_Scope
))
4039 -- Find entry for parent unit in scope stack
4041 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4047 Set_Next_Use_Clause
(N
,
4048 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4049 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4050 end Chain_Use_Clause
;
4052 ---------------------------
4053 -- Check_Frozen_Renaming --
4054 ---------------------------
4056 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4061 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4064 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4066 if Is_Entity_Name
(Name
(N
)) then
4067 Old_S
:= Entity
(Name
(N
));
4069 if not Is_Frozen
(Old_S
)
4070 and then Operating_Mode
/= Check_Semantics
4072 Append_Freeze_Action
(Old_S
, B_Node
);
4074 Insert_After
(N
, B_Node
);
4078 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4080 ("subprogram used in renaming_as_body cannot be intrinsic",
4085 Insert_After
(N
, B_Node
);
4089 end Check_Frozen_Renaming
;
4091 -------------------------------
4092 -- Set_Entity_Or_Discriminal --
4093 -------------------------------
4095 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4099 -- If the entity is not a discriminant, or else expansion is disabled,
4100 -- simply set the entity.
4102 if not In_Spec_Expression
4103 or else Ekind
(E
) /= E_Discriminant
4104 or else Inside_A_Generic
4106 Set_Entity_With_Checks
(N
, E
);
4108 -- The replacement of a discriminant by the corresponding discriminal
4109 -- is not done for a task discriminant that appears in a default
4110 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4111 -- for details on their handling.
4113 elsif Is_Concurrent_Type
(Scope
(E
)) then
4116 and then not Nkind_In
(P
, N_Parameter_Specification
,
4117 N_Component_Declaration
)
4123 and then Nkind
(P
) = N_Parameter_Specification
4128 Set_Entity
(N
, Discriminal
(E
));
4131 -- Otherwise, this is a discriminant in a context in which
4132 -- it is a reference to the corresponding parameter of the
4133 -- init proc for the enclosing type.
4136 Set_Entity
(N
, Discriminal
(E
));
4138 end Set_Entity_Or_Discriminal
;
4140 -----------------------------------
4141 -- Check_In_Previous_With_Clause --
4142 -----------------------------------
4144 procedure Check_In_Previous_With_Clause
4148 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4153 Item
:= First
(Context_Items
(Parent
(N
)));
4154 while Present
(Item
) and then Item
/= N
loop
4155 if Nkind
(Item
) = N_With_Clause
4157 -- Protect the frontend against previous critical errors
4159 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4160 and then Entity
(Name
(Item
)) = Pack
4164 -- Find root library unit in with_clause
4166 while Nkind
(Par
) = N_Expanded_Name
loop
4167 Par
:= Prefix
(Par
);
4170 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4171 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4180 -- On exit, package is not mentioned in a previous with_clause.
4181 -- Check if its prefix is.
4183 if Nkind
(Nam
) = N_Expanded_Name
then
4184 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4186 elsif Pack
/= Any_Id
then
4187 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4189 end Check_In_Previous_With_Clause
;
4191 ---------------------------------
4192 -- Check_Library_Unit_Renaming --
4193 ---------------------------------
4195 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4199 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4202 -- Check for library unit. Note that we used to check for the scope
4203 -- being Standard here, but that was wrong for Standard itself.
4205 elsif not Is_Compilation_Unit
(Old_E
)
4206 and then not Is_Child_Unit
(Old_E
)
4208 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4210 -- Entities defined in Standard (operators and boolean literals) cannot
4211 -- be renamed as library units.
4213 elsif Scope
(Old_E
) = Standard_Standard
4214 and then Sloc
(Old_E
) = Standard_Location
4216 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4218 elsif Present
(Parent_Spec
(N
))
4219 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4220 and then not Is_Child_Unit
(Old_E
)
4223 ("renamed unit must be a child unit of generic parent", Name
(N
));
4225 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4226 and then Nkind
(Name
(N
)) = N_Expanded_Name
4227 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4228 and then Is_Generic_Unit
(Old_E
)
4231 ("renamed generic unit must be a library unit", Name
(N
));
4233 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4235 -- Inherit categorization flags
4237 New_E
:= Defining_Entity
(N
);
4238 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4239 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4240 Set_Is_Remote_Call_Interface
(New_E
,
4241 Is_Remote_Call_Interface
(Old_E
));
4242 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4243 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4245 end Check_Library_Unit_Renaming
;
4247 ------------------------
4248 -- Enclosing_Instance --
4249 ------------------------
4251 function Enclosing_Instance
return Entity_Id
is
4255 if not Is_Generic_Instance
(Current_Scope
) then
4259 S
:= Scope
(Current_Scope
);
4260 while S
/= Standard_Standard
loop
4261 if Is_Generic_Instance
(S
) then
4269 end Enclosing_Instance
;
4275 procedure End_Scope
is
4281 Id
:= First_Entity
(Current_Scope
);
4282 while Present
(Id
) loop
4283 -- An entity in the current scope is not necessarily the first one
4284 -- on its homonym chain. Find its predecessor if any,
4285 -- If it is an internal entity, it will not be in the visibility
4286 -- chain altogether, and there is nothing to unchain.
4288 if Id
/= Current_Entity
(Id
) then
4289 Prev
:= Current_Entity
(Id
);
4290 while Present
(Prev
)
4291 and then Present
(Homonym
(Prev
))
4292 and then Homonym
(Prev
) /= Id
4294 Prev
:= Homonym
(Prev
);
4297 -- Skip to end of loop if Id is not in the visibility chain
4299 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4307 Set_Is_Immediately_Visible
(Id
, False);
4309 Outer
:= Homonym
(Id
);
4310 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4311 Outer
:= Homonym
(Outer
);
4314 -- Reset homonym link of other entities, but do not modify link
4315 -- between entities in current scope, so that the back-end can have
4316 -- a proper count of local overloadings.
4319 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4321 elsif Scope
(Prev
) /= Scope
(Id
) then
4322 Set_Homonym
(Prev
, Outer
);
4329 -- If the scope generated freeze actions, place them before the
4330 -- current declaration and analyze them. Type declarations and
4331 -- the bodies of initialization procedures can generate such nodes.
4332 -- We follow the parent chain until we reach a list node, which is
4333 -- the enclosing list of declarations. If the list appears within
4334 -- a protected definition, move freeze nodes outside the protected
4338 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4342 L
: constant List_Id
:= Scope_Stack
.Table
4343 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4346 if Is_Itype
(Current_Scope
) then
4347 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4349 Decl
:= Parent
(Current_Scope
);
4354 while not (Is_List_Member
(Decl
))
4355 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4358 Decl
:= Parent
(Decl
);
4361 Insert_List_Before_And_Analyze
(Decl
, L
);
4369 ---------------------
4370 -- End_Use_Clauses --
4371 ---------------------
4373 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4377 -- Remove Use_Type clauses first, because they affect the
4378 -- visibility of operators in subsequent used packages.
4381 while Present
(U
) loop
4382 if Nkind
(U
) = N_Use_Type_Clause
then
4386 Next_Use_Clause
(U
);
4390 while Present
(U
) loop
4391 if Nkind
(U
) = N_Use_Package_Clause
then
4392 End_Use_Package
(U
);
4395 Next_Use_Clause
(U
);
4397 end End_Use_Clauses
;
4399 ---------------------
4400 -- End_Use_Package --
4401 ---------------------
4403 procedure End_Use_Package
(N
: Node_Id
) is
4404 Pack_Name
: Node_Id
;
4409 function Is_Primitive_Operator_In_Use
4411 F
: Entity_Id
) return Boolean;
4412 -- Check whether Op is a primitive operator of a use-visible type
4414 ----------------------------------
4415 -- Is_Primitive_Operator_In_Use --
4416 ----------------------------------
4418 function Is_Primitive_Operator_In_Use
4420 F
: Entity_Id
) return Boolean
4422 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4424 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4425 end Is_Primitive_Operator_In_Use
;
4427 -- Start of processing for End_Use_Package
4430 Pack_Name
:= First
(Names
(N
));
4431 while Present
(Pack_Name
) loop
4433 -- Test that Pack_Name actually denotes a package before processing
4435 if Is_Entity_Name
(Pack_Name
)
4436 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4438 Pack
:= Entity
(Pack_Name
);
4440 if In_Open_Scopes
(Pack
) then
4443 elsif not Redundant_Use
(Pack_Name
) then
4444 Set_In_Use
(Pack
, False);
4445 Set_Current_Use_Clause
(Pack
, Empty
);
4447 Id
:= First_Entity
(Pack
);
4448 while Present
(Id
) loop
4450 -- Preserve use-visibility of operators that are primitive
4451 -- operators of a type that is use-visible through an active
4454 if Nkind
(Id
) = N_Defining_Operator_Symbol
4456 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4458 (Present
(Next_Formal
(First_Formal
(Id
)))
4460 Is_Primitive_Operator_In_Use
4461 (Id
, Next_Formal
(First_Formal
(Id
)))))
4465 Set_Is_Potentially_Use_Visible
(Id
, False);
4468 if Is_Private_Type
(Id
)
4469 and then Present
(Full_View
(Id
))
4471 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4477 if Present
(Renamed_Object
(Pack
)) then
4478 Set_In_Use
(Renamed_Object
(Pack
), False);
4479 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4482 if Chars
(Pack
) = Name_System
4483 and then Scope
(Pack
) = Standard_Standard
4484 and then Present_System_Aux
4486 Id
:= First_Entity
(System_Aux_Id
);
4487 while Present
(Id
) loop
4488 Set_Is_Potentially_Use_Visible
(Id
, False);
4490 if Is_Private_Type
(Id
)
4491 and then Present
(Full_View
(Id
))
4493 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4499 Set_In_Use
(System_Aux_Id
, False);
4503 Set_Redundant_Use
(Pack_Name
, False);
4510 if Present
(Hidden_By_Use_Clause
(N
)) then
4511 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4512 while Present
(Elmt
) loop
4514 E
: constant Entity_Id
:= Node
(Elmt
);
4517 -- Reset either Use_Visibility or Direct_Visibility, depending
4518 -- on how the entity was hidden by the use clause.
4520 if In_Use
(Scope
(E
))
4521 and then Used_As_Generic_Actual
(Scope
(E
))
4523 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4525 Set_Is_Immediately_Visible
(Node
(Elmt
));
4532 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4534 end End_Use_Package
;
4540 procedure End_Use_Type
(N
: Node_Id
) is
4545 -- Start of processing for End_Use_Type
4548 Id
:= First
(Subtype_Marks
(N
));
4549 while Present
(Id
) loop
4551 -- A call to Rtsfind may occur while analyzing a use_type clause,
4552 -- in which case the type marks are not resolved yet, and there is
4553 -- nothing to remove.
4555 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4561 if T
= Any_Type
or else From_Limited_With
(T
) then
4564 -- Note that the use_type clause may mention a subtype of the type
4565 -- whose primitive operations have been made visible. Here as
4566 -- elsewhere, it is the base type that matters for visibility.
4568 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4571 elsif not Redundant_Use
(Id
) then
4572 Set_In_Use
(T
, False);
4573 Set_In_Use
(Base_Type
(T
), False);
4574 Set_Current_Use_Clause
(T
, Empty
);
4575 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4582 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4586 Elmt
:= First_Elmt
(Used_Operations
(N
));
4587 while Present
(Elmt
) loop
4588 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4594 ----------------------
4595 -- Find_Direct_Name --
4596 ----------------------
4598 procedure Find_Direct_Name
(N
: Node_Id
) is
4603 Inst
: Entity_Id
:= Empty
;
4604 -- Enclosing instance, if any
4606 Homonyms
: Entity_Id
;
4607 -- Saves start of homonym chain
4609 Nvis_Entity
: Boolean;
4610 -- Set True to indicate that there is at least one entity on the homonym
4611 -- chain which, while not visible, is visible enough from the user point
4612 -- of view to warrant an error message of "not visible" rather than
4615 Nvis_Is_Private_Subprg
: Boolean := False;
4616 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4617 -- effect concerning library subprograms has been detected. Used to
4618 -- generate the precise error message.
4620 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4621 -- Returns true if the entity is an actual for a package that is itself
4622 -- an actual for a formal package of the current instance. Such an
4623 -- entity requires special handling because it may be use-visible but
4624 -- hides directly visible entities defined outside the instance, because
4625 -- the corresponding formal did so in the generic.
4627 function Is_Actual_Parameter
return Boolean;
4628 -- This function checks if the node N is an identifier that is an actual
4629 -- parameter of a procedure call. If so it returns True, otherwise it
4630 -- return False. The reason for this check is that at this stage we do
4631 -- not know what procedure is being called if the procedure might be
4632 -- overloaded, so it is premature to go setting referenced flags or
4633 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4634 -- for that processing
4636 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4637 -- This function determines whether a reference to the entity E, which
4638 -- is not visible, can reasonably be considered to be known to the
4639 -- writer of the reference. This is a heuristic test, used only for
4640 -- the purposes of figuring out whether we prefer to complain that an
4641 -- entity is undefined or invisible (and identify the declaration of
4642 -- the invisible entity in the latter case). The point here is that we
4643 -- don't want to complain that something is invisible and then point to
4644 -- something entirely mysterious to the writer.
4646 procedure Nvis_Messages
;
4647 -- Called if there are no visible entries for N, but there is at least
4648 -- one non-directly visible, or hidden declaration. This procedure
4649 -- outputs an appropriate set of error messages.
4651 procedure Undefined
(Nvis
: Boolean);
4652 -- This function is called if the current node has no corresponding
4653 -- visible entity or entities. The value set in Msg indicates whether
4654 -- an error message was generated (multiple error messages for the
4655 -- same variable are generally suppressed, see body for details).
4656 -- Msg is True if an error message was generated, False if not. This
4657 -- value is used by the caller to determine whether or not to output
4658 -- additional messages where appropriate. The parameter is set False
4659 -- to get the message "X is undefined", and True to get the message
4660 -- "X is not visible".
4662 -------------------------
4663 -- From_Actual_Package --
4664 -------------------------
4666 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4667 Scop
: constant Entity_Id
:= Scope
(E
);
4668 -- Declared scope of candidate entity
4672 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4673 -- Recursive function that does the work and examines actuals of
4674 -- actual packages of current instance.
4676 ------------------------
4677 -- Declared_In_Actual --
4678 ------------------------
4680 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4684 if No
(Associated_Formal_Package
(Pack
)) then
4688 Act
:= First_Entity
(Pack
);
4689 while Present
(Act
) loop
4690 if Renamed_Object
(Pack
) = Scop
then
4693 -- Check for end of list of actuals.
4695 elsif Ekind
(Act
) = E_Package
4696 and then Renamed_Object
(Act
) = Pack
4700 elsif Ekind
(Act
) = E_Package
4701 and then Declared_In_Actual
(Act
)
4711 end Declared_In_Actual
;
4713 -- Start of processing for From_Actual_Package
4716 if not In_Instance
then
4720 Inst
:= Current_Scope
;
4721 while Present
(Inst
)
4722 and then Ekind
(Inst
) /= E_Package
4723 and then not Is_Generic_Instance
(Inst
)
4725 Inst
:= Scope
(Inst
);
4732 Act
:= First_Entity
(Inst
);
4733 while Present
(Act
) loop
4734 if Ekind
(Act
) = E_Package
4735 and then Declared_In_Actual
(Act
)
4745 end From_Actual_Package
;
4747 -------------------------
4748 -- Is_Actual_Parameter --
4749 -------------------------
4751 function Is_Actual_Parameter
return Boolean is
4754 Nkind
(N
) = N_Identifier
4756 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4758 (Nkind
(Parent
(N
)) = N_Parameter_Association
4759 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4760 and then Nkind
(Parent
(Parent
(N
))) =
4761 N_Procedure_Call_Statement
));
4762 end Is_Actual_Parameter
;
4764 -------------------------
4765 -- Known_But_Invisible --
4766 -------------------------
4768 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4769 Fname
: File_Name_Type
;
4772 -- Entities in Standard are always considered to be known
4774 if Sloc
(E
) <= Standard_Location
then
4777 -- An entity that does not come from source is always considered
4778 -- to be unknown, since it is an artifact of code expansion.
4780 elsif not Comes_From_Source
(E
) then
4783 -- In gnat internal mode, we consider all entities known. The
4784 -- historical reason behind this discrepancy is not known??? But the
4785 -- only effect is to modify the error message given, so it is not
4786 -- critical. Since it only affects the exact wording of error
4787 -- messages in illegal programs, we do not mention this as an
4788 -- effect of -gnatg, since it is not a language modification.
4790 elsif GNAT_Mode
then
4794 -- Here we have an entity that is not from package Standard, and
4795 -- which comes from Source. See if it comes from an internal file.
4797 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4799 -- Case of from internal file
4801 if Is_Internal_File_Name
(Fname
) then
4803 -- Private part entities in internal files are never considered
4804 -- to be known to the writer of normal application code.
4806 if Is_Hidden
(E
) then
4810 -- Entities from System packages other than System and
4811 -- System.Storage_Elements are not considered to be known.
4812 -- System.Auxxxx files are also considered known to the user.
4814 -- Should refine this at some point to generally distinguish
4815 -- between known and unknown internal files ???
4817 Get_Name_String
(Fname
);
4822 Name_Buffer
(1 .. 2) /= "s-"
4824 Name_Buffer
(3 .. 8) = "stoele"
4826 Name_Buffer
(3 .. 5) = "aux";
4828 -- If not an internal file, then entity is definitely known,
4829 -- even if it is in a private part (the message generated will
4830 -- note that it is in a private part)
4835 end Known_But_Invisible
;
4841 procedure Nvis_Messages
is
4842 Comp_Unit
: Node_Id
;
4844 Found
: Boolean := False;
4845 Hidden
: Boolean := False;
4849 -- Ada 2005 (AI-262): Generate a precise error concerning the
4850 -- Beaujolais effect that was previously detected
4852 if Nvis_Is_Private_Subprg
then
4854 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4855 and then Ekind
(E2
) = E_Function
4856 and then Scope
(E2
) = Standard_Standard
4857 and then Has_Private_With
(E2
));
4859 -- Find the sloc corresponding to the private with'ed unit
4861 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4862 Error_Msg_Sloc
:= No_Location
;
4864 Item
:= First
(Context_Items
(Comp_Unit
));
4865 while Present
(Item
) loop
4866 if Nkind
(Item
) = N_With_Clause
4867 and then Private_Present
(Item
)
4868 and then Entity
(Name
(Item
)) = E2
4870 Error_Msg_Sloc
:= Sloc
(Item
);
4877 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4879 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4883 Undefined
(Nvis
=> True);
4887 -- First loop does hidden declarations
4890 while Present
(Ent
) loop
4891 if Is_Potentially_Use_Visible
(Ent
) then
4893 Error_Msg_N
-- CODEFIX
4894 ("multiple use clauses cause hiding!", N
);
4898 Error_Msg_Sloc
:= Sloc
(Ent
);
4899 Error_Msg_N
-- CODEFIX
4900 ("hidden declaration#!", N
);
4903 Ent
:= Homonym
(Ent
);
4906 -- If we found hidden declarations, then that's enough, don't
4907 -- bother looking for non-visible declarations as well.
4913 -- Second loop does non-directly visible declarations
4916 while Present
(Ent
) loop
4917 if not Is_Potentially_Use_Visible
(Ent
) then
4919 -- Do not bother the user with unknown entities
4921 if not Known_But_Invisible
(Ent
) then
4925 Error_Msg_Sloc
:= Sloc
(Ent
);
4927 -- Output message noting that there is a non-visible
4928 -- declaration, distinguishing the private part case.
4930 if Is_Hidden
(Ent
) then
4931 Error_Msg_N
("non-visible (private) declaration#!", N
);
4933 -- If the entity is declared in a generic package, it
4934 -- cannot be visible, so there is no point in adding it
4935 -- to the list of candidates if another homograph from a
4936 -- non-generic package has been seen.
4938 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4944 Error_Msg_N
-- CODEFIX
4945 ("non-visible declaration#!", N
);
4947 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
4951 if Is_Compilation_Unit
(Ent
)
4953 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
4955 Error_Msg_Qual_Level
:= 99;
4956 Error_Msg_NE
-- CODEFIX
4957 ("\\missing `WITH &;`", N
, Ent
);
4958 Error_Msg_Qual_Level
:= 0;
4961 if Ekind
(Ent
) = E_Discriminant
4962 and then Present
(Corresponding_Discriminant
(Ent
))
4963 and then Scope
(Corresponding_Discriminant
(Ent
)) =
4967 ("inherited discriminant not allowed here" &
4968 " (RM 3.8 (12), 3.8.1 (6))!", N
);
4972 -- Set entity and its containing package as referenced. We
4973 -- can't be sure of this, but this seems a better choice
4974 -- to avoid unused entity messages.
4976 if Comes_From_Source
(Ent
) then
4977 Set_Referenced
(Ent
);
4978 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
4983 Ent
:= Homonym
(Ent
);
4992 procedure Undefined
(Nvis
: Boolean) is
4993 Emsg
: Error_Msg_Id
;
4996 -- We should never find an undefined internal name. If we do, then
4997 -- see if we have previous errors. If so, ignore on the grounds that
4998 -- it is probably a cascaded message (e.g. a block label from a badly
4999 -- formed block). If no previous errors, then we have a real internal
5000 -- error of some kind so raise an exception.
5002 if Is_Internal_Name
(Chars
(N
)) then
5003 if Total_Errors_Detected
/= 0 then
5006 raise Program_Error
;
5010 -- A very specialized error check, if the undefined variable is
5011 -- a case tag, and the case type is an enumeration type, check
5012 -- for a possible misspelling, and if so, modify the identifier
5014 -- Named aggregate should also be handled similarly ???
5016 if Nkind
(N
) = N_Identifier
5017 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5020 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5021 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5026 if Is_Enumeration_Type
(Case_Typ
)
5027 and then not Is_Standard_Character_Type
(Case_Typ
)
5029 Lit
:= First_Literal
(Case_Typ
);
5030 Get_Name_String
(Chars
(Lit
));
5032 if Chars
(Lit
) /= Chars
(N
)
5033 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5035 Error_Msg_Node_2
:= Lit
;
5036 Error_Msg_N
-- CODEFIX
5037 ("& is undefined, assume misspelling of &", N
);
5038 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5042 Lit
:= Next_Literal
(Lit
);
5047 -- Normal processing
5049 Set_Entity
(N
, Any_Id
);
5050 Set_Etype
(N
, Any_Type
);
5052 -- We use the table Urefs to keep track of entities for which we
5053 -- have issued errors for undefined references. Multiple errors
5054 -- for a single name are normally suppressed, however we modify
5055 -- the error message to alert the programmer to this effect.
5057 for J
in Urefs
.First
.. Urefs
.Last
loop
5058 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5059 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5060 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5062 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5064 if Urefs
.Table
(J
).Nvis
then
5065 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5066 "& is not visible (more references follow)");
5068 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5069 "& is undefined (more references follow)");
5072 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5075 -- Although we will set Msg False, and thus suppress the
5076 -- message, we also set Error_Posted True, to avoid any
5077 -- cascaded messages resulting from the undefined reference.
5080 Set_Error_Posted
(N
, True);
5085 -- If entry not found, this is first undefined occurrence
5088 Error_Msg_N
("& is not visible!", N
);
5092 Error_Msg_N
("& is undefined!", N
);
5095 -- A very bizarre special check, if the undefined identifier
5096 -- is put or put_line, then add a special error message (since
5097 -- this is a very common error for beginners to make).
5099 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5100 Error_Msg_N
-- CODEFIX
5101 ("\\possible missing `WITH Ada.Text_'I'O; " &
5102 "USE Ada.Text_'I'O`!", N
);
5104 -- Another special check if N is the prefix of a selected
5105 -- component which is a known unit, add message complaining
5106 -- about missing with for this unit.
5108 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5109 and then N
= Prefix
(Parent
(N
))
5110 and then Is_Known_Unit
(Parent
(N
))
5112 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5113 Error_Msg_N
-- CODEFIX
5114 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5117 -- Now check for possible misspellings
5121 Ematch
: Entity_Id
:= Empty
;
5123 Last_Name_Id
: constant Name_Id
:=
5124 Name_Id
(Nat
(First_Name_Id
) +
5125 Name_Entries_Count
- 1);
5128 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5129 E
:= Get_Name_Entity_Id
(Nam
);
5132 and then (Is_Immediately_Visible
(E
)
5134 Is_Potentially_Use_Visible
(E
))
5136 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5143 if Present
(Ematch
) then
5144 Error_Msg_NE
-- CODEFIX
5145 ("\possible misspelling of&", N
, Ematch
);
5150 -- Make entry in undefined references table unless the full errors
5151 -- switch is set, in which case by refraining from generating the
5152 -- table entry, we guarantee that we get an error message for every
5153 -- undefined reference.
5155 if not All_Errors_Mode
then
5166 -- Start of processing for Find_Direct_Name
5169 -- If the entity pointer is already set, this is an internal node, or
5170 -- a node that is analyzed more than once, after a tree modification.
5171 -- In such a case there is no resolution to perform, just set the type.
5173 if Present
(Entity
(N
)) then
5174 if Is_Type
(Entity
(N
)) then
5175 Set_Etype
(N
, Entity
(N
));
5179 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5182 -- One special case here. If the Etype field is already set,
5183 -- and references the packed array type corresponding to the
5184 -- etype of the referenced entity, then leave it alone. This
5185 -- happens for trees generated from Exp_Pakd, where expressions
5186 -- can be deliberately "mis-typed" to the packed array type.
5188 if Is_Array_Type
(Entyp
)
5189 and then Is_Packed
(Entyp
)
5190 and then Present
(Etype
(N
))
5191 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5195 -- If not that special case, then just reset the Etype
5198 Set_Etype
(N
, Etype
(Entity
(N
)));
5206 -- Here if Entity pointer was not set, we need full visibility analysis
5207 -- First we generate debugging output if the debug E flag is set.
5209 if Debug_Flag_E
then
5210 Write_Str
("Looking for ");
5211 Write_Name
(Chars
(N
));
5215 Homonyms
:= Current_Entity
(N
);
5216 Nvis_Entity
:= False;
5219 while Present
(E
) loop
5221 -- If entity is immediately visible or potentially use visible, then
5222 -- process the entity and we are done.
5224 if Is_Immediately_Visible
(E
) then
5225 goto Immediately_Visible_Entity
;
5227 elsif Is_Potentially_Use_Visible
(E
) then
5228 goto Potentially_Use_Visible_Entity
;
5230 -- Note if a known but invisible entity encountered
5232 elsif Known_But_Invisible
(E
) then
5233 Nvis_Entity
:= True;
5236 -- Move to next entity in chain and continue search
5241 -- If no entries on homonym chain that were potentially visible,
5242 -- and no entities reasonably considered as non-visible, then
5243 -- we have a plain undefined reference, with no additional
5244 -- explanation required.
5246 if not Nvis_Entity
then
5247 Undefined
(Nvis
=> False);
5249 -- Otherwise there is at least one entry on the homonym chain that
5250 -- is reasonably considered as being known and non-visible.
5258 -- Processing for a potentially use visible entry found. We must search
5259 -- the rest of the homonym chain for two reasons. First, if there is a
5260 -- directly visible entry, then none of the potentially use-visible
5261 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5262 -- for the case of multiple potentially use-visible entries hiding one
5263 -- another and as a result being non-directly visible (RM 8.4(11)).
5265 <<Potentially_Use_Visible_Entity
>> declare
5266 Only_One_Visible
: Boolean := True;
5267 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5271 while Present
(E2
) loop
5272 if Is_Immediately_Visible
(E2
) then
5274 -- If the use-visible entity comes from the actual for a
5275 -- formal package, it hides a directly visible entity from
5276 -- outside the instance.
5278 if From_Actual_Package
(E
)
5279 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5284 goto Immediately_Visible_Entity
;
5287 elsif Is_Potentially_Use_Visible
(E2
) then
5288 Only_One_Visible
:= False;
5289 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5291 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5292 -- that can occur in private_with clauses. Example:
5295 -- private with B; package A is
5296 -- package C is function B return Integer;
5298 -- V1 : Integer := B;
5299 -- private function B return Integer;
5300 -- V2 : Integer := B;
5303 -- V1 resolves to A.B, but V2 resolves to library unit B
5305 elsif Ekind
(E2
) = E_Function
5306 and then Scope
(E2
) = Standard_Standard
5307 and then Has_Private_With
(E2
)
5309 Only_One_Visible
:= False;
5310 All_Overloadable
:= False;
5311 Nvis_Is_Private_Subprg
:= True;
5318 -- On falling through this loop, we have checked that there are no
5319 -- immediately visible entities. Only_One_Visible is set if exactly
5320 -- one potentially use visible entity exists. All_Overloadable is
5321 -- set if all the potentially use visible entities are overloadable.
5322 -- The condition for legality is that either there is one potentially
5323 -- use visible entity, or if there is more than one, then all of them
5324 -- are overloadable.
5326 if Only_One_Visible
or All_Overloadable
then
5329 -- If there is more than one potentially use-visible entity and at
5330 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5331 -- Note that E points to the first such entity on the homonym list.
5332 -- Special case: if one of the entities is declared in an actual
5333 -- package, it was visible in the generic, and takes precedence over
5334 -- other entities that are potentially use-visible. Same if it is
5335 -- declared in a local instantiation of the current instance.
5340 -- Find current instance
5342 Inst
:= Current_Scope
;
5343 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5344 if Is_Generic_Instance
(Inst
) then
5348 Inst
:= Scope
(Inst
);
5352 while Present
(E2
) loop
5353 if From_Actual_Package
(E2
)
5355 (Is_Generic_Instance
(Scope
(E2
))
5356 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5369 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5371 -- A use-clause in the body of a system file creates conflict
5372 -- with some entity in a user scope, while rtsfind is active.
5373 -- Keep only the entity coming from another predefined unit.
5376 while Present
(E2
) loop
5377 if Is_Predefined_File_Name
5378 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5387 -- Entity must exist because predefined unit is correct
5389 raise Program_Error
;
5398 -- Come here with E set to the first immediately visible entity on
5399 -- the homonym chain. This is the one we want unless there is another
5400 -- immediately visible entity further on in the chain for an inner
5401 -- scope (RM 8.3(8)).
5403 <<Immediately_Visible_Entity
>> declare
5408 -- Find scope level of initial entity. When compiling through
5409 -- Rtsfind, the previous context is not completely invisible, and
5410 -- an outer entity may appear on the chain, whose scope is below
5411 -- the entry for Standard that delimits the current scope stack.
5412 -- Indicate that the level for this spurious entry is outside of
5413 -- the current scope stack.
5415 Level
:= Scope_Stack
.Last
;
5417 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5418 exit when Scop
= Scope
(E
);
5420 exit when Scop
= Standard_Standard
;
5423 -- Now search remainder of homonym chain for more inner entry
5424 -- If the entity is Standard itself, it has no scope, and we
5425 -- compare it with the stack entry directly.
5428 while Present
(E2
) loop
5429 if Is_Immediately_Visible
(E2
) then
5431 -- If a generic package contains a local declaration that
5432 -- has the same name as the generic, there may be a visibility
5433 -- conflict in an instance, where the local declaration must
5434 -- also hide the name of the corresponding package renaming.
5435 -- We check explicitly for a package declared by a renaming,
5436 -- whose renamed entity is an instance that is on the scope
5437 -- stack, and that contains a homonym in the same scope. Once
5438 -- we have found it, we know that the package renaming is not
5439 -- immediately visible, and that the identifier denotes the
5440 -- other entity (and its homonyms if overloaded).
5442 if Scope
(E
) = Scope
(E2
)
5443 and then Ekind
(E
) = E_Package
5444 and then Present
(Renamed_Object
(E
))
5445 and then Is_Generic_Instance
(Renamed_Object
(E
))
5446 and then In_Open_Scopes
(Renamed_Object
(E
))
5447 and then Comes_From_Source
(N
)
5449 Set_Is_Immediately_Visible
(E
, False);
5453 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5454 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5455 or else Scope_Stack
.Table
(J
).Entity
= E2
5468 -- At the end of that loop, E is the innermost immediately
5469 -- visible entity, so we are all set.
5472 -- Come here with entity found, and stored in E
5476 -- Check violation of No_Wide_Characters restriction
5478 Check_Wide_Character_Restriction
(E
, N
);
5480 -- When distribution features are available (Get_PCS_Name /=
5481 -- Name_No_DSA), a remote access-to-subprogram type is converted
5482 -- into a record type holding whatever information is needed to
5483 -- perform a remote call on an RCI subprogram. In that case we
5484 -- rewrite any occurrence of the RAS type into the equivalent record
5485 -- type here. 'Access attribute references and RAS dereferences are
5486 -- then implemented using specific TSSs. However when distribution is
5487 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5488 -- generation of these TSSs, and we must keep the RAS type in its
5489 -- original access-to-subprogram form (since all calls through a
5490 -- value of such type will be local anyway in the absence of a PCS).
5492 if Comes_From_Source
(N
)
5493 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5494 and then Ekind
(E
) = E_Access_Subprogram_Type
5495 and then Expander_Active
5496 and then Get_PCS_Name
/= Name_No_DSA
5498 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5502 -- Set the entity. Note that the reason we call Set_Entity for the
5503 -- overloadable case, as opposed to Set_Entity_With_Checks is
5504 -- that in the overloaded case, the initial call can set the wrong
5505 -- homonym. The call that sets the right homonym is in Sem_Res and
5506 -- that call does use Set_Entity_With_Checks, so we don't miss
5509 if Is_Overloadable
(E
) then
5512 Set_Entity_With_Checks
(N
, E
);
5518 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5521 if Debug_Flag_E
then
5522 Write_Str
(" found ");
5523 Write_Entity_Info
(E
, " ");
5526 -- If the Ekind of the entity is Void, it means that all homonyms
5527 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5528 -- test is skipped if the current scope is a record and the name is
5529 -- a pragma argument expression (case of Atomic and Volatile pragmas
5530 -- and possibly other similar pragmas added later, which are allowed
5531 -- to reference components in the current record).
5533 if Ekind
(E
) = E_Void
5535 (not Is_Record_Type
(Current_Scope
)
5536 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5538 Premature_Usage
(N
);
5540 -- If the entity is overloadable, collect all interpretations of the
5541 -- name for subsequent overload resolution. We optimize a bit here to
5542 -- do this only if we have an overloadable entity that is not on its
5543 -- own on the homonym chain.
5545 elsif Is_Overloadable
(E
)
5546 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5548 Collect_Interps
(N
);
5550 -- If no homonyms were visible, the entity is unambiguous
5552 if not Is_Overloaded
(N
) then
5553 if not Is_Actual_Parameter
then
5554 Generate_Reference
(E
, N
);
5558 -- Case of non-overloadable entity, set the entity providing that
5559 -- we do not have the case of a discriminant reference within a
5560 -- default expression. Such references are replaced with the
5561 -- corresponding discriminal, which is the formal corresponding to
5562 -- to the discriminant in the initialization procedure.
5565 -- Entity is unambiguous, indicate that it is referenced here
5567 -- For a renaming of an object, always generate simple reference,
5568 -- we don't try to keep track of assignments in this case, except
5569 -- in SPARK mode where renamings are traversed for generating
5570 -- local effects of subprograms.
5573 and then Present
(Renamed_Object
(E
))
5574 and then not GNATprove_Mode
5576 Generate_Reference
(E
, N
);
5578 -- If the renamed entity is a private protected component,
5579 -- reference the original component as well. This needs to be
5580 -- done because the private renamings are installed before any
5581 -- analysis has occurred. Reference to a private component will
5582 -- resolve to the renaming and the original component will be
5583 -- left unreferenced, hence the following.
5585 if Is_Prival
(E
) then
5586 Generate_Reference
(Prival_Link
(E
), N
);
5589 -- One odd case is that we do not want to set the Referenced flag
5590 -- if the entity is a label, and the identifier is the label in
5591 -- the source, since this is not a reference from the point of
5592 -- view of the user.
5594 elsif Nkind
(Parent
(N
)) = N_Label
then
5596 R
: constant Boolean := Referenced
(E
);
5599 -- Generate reference unless this is an actual parameter
5600 -- (see comment below)
5602 if Is_Actual_Parameter
then
5603 Generate_Reference
(E
, N
);
5604 Set_Referenced
(E
, R
);
5608 -- Normal case, not a label: generate reference
5611 if not Is_Actual_Parameter
then
5613 -- Package or generic package is always a simple reference
5615 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5616 Generate_Reference
(E
, N
, 'r');
5618 -- Else see if we have a left hand side
5623 Generate_Reference
(E
, N
, 'm');
5626 Generate_Reference
(E
, N
, 'r');
5628 -- If we don't know now, generate reference later
5631 Deferred_References
.Append
((E
, N
));
5636 Check_Nested_Access
(E
);
5639 Set_Entity_Or_Discriminal
(N
, E
);
5641 -- The name may designate a generalized reference, in which case
5642 -- the dereference interpretation will be included.
5644 if Ada_Version
>= Ada_2012
5646 (Nkind
(Parent
(N
)) in N_Subexpr
5647 or else Nkind_In
(Parent
(N
), N_Object_Declaration
,
5648 N_Assignment_Statement
))
5650 Check_Implicit_Dereference
(N
, Etype
(E
));
5655 -- Come here with entity set
5658 Check_Restriction_No_Use_Of_Entity
(N
);
5659 end Find_Direct_Name
;
5661 ------------------------
5662 -- Find_Expanded_Name --
5663 ------------------------
5665 -- This routine searches the homonym chain of the entity until it finds
5666 -- an entity declared in the scope denoted by the prefix. If the entity
5667 -- is private, it may nevertheless be immediately visible, if we are in
5668 -- the scope of its declaration.
5670 procedure Find_Expanded_Name
(N
: Node_Id
) is
5671 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean;
5672 -- Determine whether an arbitrary node N appears in pragmas [Refined_]
5673 -- Depends or [Refined_]Global.
5675 ----------------------------------
5676 -- In_Pragmas_Depends_Or_Global --
5677 ----------------------------------
5679 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean is
5683 -- Climb the parent chain looking for a pragma
5686 while Present
(Par
) loop
5687 if Nkind
(Par
) = N_Pragma
5688 and then Nam_In
(Pragma_Name
(Par
), Name_Depends
,
5690 Name_Refined_Depends
,
5691 Name_Refined_Global
)
5695 -- Prevent the search from going too far
5697 elsif Is_Body_Or_Package_Declaration
(Par
) then
5701 Par
:= Parent
(Par
);
5705 end In_Pragmas_Depends_Or_Global
;
5709 Selector
: constant Node_Id
:= Selector_Name
(N
);
5710 Candidate
: Entity_Id
:= Empty
;
5714 -- Start of processing for Find_Expanded_Name
5717 P_Name
:= Entity
(Prefix
(N
));
5719 -- If the prefix is a renamed package, look for the entity in the
5720 -- original package.
5722 if Ekind
(P_Name
) = E_Package
5723 and then Present
(Renamed_Object
(P_Name
))
5725 P_Name
:= Renamed_Object
(P_Name
);
5727 -- Rewrite node with entity field pointing to renamed object
5729 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5730 Set_Entity
(Prefix
(N
), P_Name
);
5732 -- If the prefix is an object of a concurrent type, look for
5733 -- the entity in the associated task or protected type.
5735 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5736 P_Name
:= Etype
(P_Name
);
5739 Id
:= Current_Entity
(Selector
);
5742 Is_New_Candidate
: Boolean;
5745 while Present
(Id
) loop
5746 if Scope
(Id
) = P_Name
then
5748 Is_New_Candidate
:= True;
5750 -- Handle abstract views of states and variables. These are
5751 -- acceptable only when the reference to the view appears in
5752 -- pragmas [Refined_]Depends and [Refined_]Global.
5754 if Ekind
(Id
) = E_Abstract_State
5755 and then From_Limited_With
(Id
)
5756 and then Present
(Non_Limited_View
(Id
))
5758 if In_Pragmas_Depends_Or_Global
(N
) then
5759 Candidate
:= Non_Limited_View
(Id
);
5760 Is_New_Candidate
:= True;
5762 -- Hide candidate because it is not used in a proper context
5766 Is_New_Candidate
:= False;
5770 -- Ada 2005 (AI-217): Handle shadow entities associated with
5771 -- types declared in limited-withed nested packages. We don't need
5772 -- to handle E_Incomplete_Subtype entities because the entities
5773 -- in the limited view are always E_Incomplete_Type and
5774 -- E_Class_Wide_Type entities (see Build_Limited_Views).
5776 -- Regarding the expression used to evaluate the scope, it
5777 -- is important to note that the limited view also has shadow
5778 -- entities associated nested packages. For this reason the
5779 -- correct scope of the entity is the scope of the real entity.
5780 -- The non-limited view may itself be incomplete, in which case
5781 -- get the full view if available.
5783 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
5784 and then From_Limited_With
(Id
)
5785 and then Present
(Non_Limited_View
(Id
))
5786 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5788 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5789 Is_New_Candidate
:= True;
5792 Is_New_Candidate
:= False;
5795 if Is_New_Candidate
then
5797 -- If entity is a child unit, either it is a visible child of
5798 -- the prefix, or we are in the body of a generic prefix, as
5799 -- will happen when a child unit is instantiated in the body
5800 -- of a generic parent. This is because the instance body does
5801 -- not restore the full compilation context, given that all
5802 -- non-local references have been captured.
5804 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5805 exit when Is_Visible_Lib_Unit
(Id
)
5806 or else (Is_Child_Unit
(Id
)
5807 and then In_Open_Scopes
(Scope
(Id
))
5808 and then In_Instance_Body
);
5810 exit when not Is_Hidden
(Id
);
5813 exit when Is_Immediately_Visible
(Id
);
5821 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5822 and then Is_Generic_Instance
(P_Name
)
5824 -- Expanded name denotes entity in (instance of) generic subprogram.
5825 -- The entity may be in the subprogram instance, or may denote one of
5826 -- the formals, which is declared in the enclosing wrapper package.
5828 P_Name
:= Scope
(P_Name
);
5830 Id
:= Current_Entity
(Selector
);
5831 while Present
(Id
) loop
5832 exit when Scope
(Id
) = P_Name
;
5837 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5838 Set_Etype
(N
, Any_Type
);
5840 -- If we are looking for an entity defined in System, try to find it
5841 -- in the child package that may have been provided as an extension
5842 -- to System. The Extend_System pragma will have supplied the name of
5843 -- the extension, which may have to be loaded.
5845 if Chars
(P_Name
) = Name_System
5846 and then Scope
(P_Name
) = Standard_Standard
5847 and then Present
(System_Extend_Unit
)
5848 and then Present_System_Aux
(N
)
5850 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5851 Find_Expanded_Name
(N
);
5854 elsif Nkind
(Selector
) = N_Operator_Symbol
5855 and then Has_Implicit_Operator
(N
)
5857 -- There is an implicit instance of the predefined operator in
5858 -- the given scope. The operator entity is defined in Standard.
5859 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5863 elsif Nkind
(Selector
) = N_Character_Literal
5864 and then Has_Implicit_Character_Literal
(N
)
5866 -- If there is no literal defined in the scope denoted by the
5867 -- prefix, the literal may belong to (a type derived from)
5868 -- Standard_Character, for which we have no explicit literals.
5873 -- If the prefix is a single concurrent object, use its name in
5874 -- the error message, rather than that of the anonymous type.
5876 if Is_Concurrent_Type
(P_Name
)
5877 and then Is_Internal_Name
(Chars
(P_Name
))
5879 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5881 Error_Msg_Node_2
:= P_Name
;
5884 if P_Name
= System_Aux_Id
then
5885 P_Name
:= Scope
(P_Name
);
5886 Set_Entity
(Prefix
(N
), P_Name
);
5889 if Present
(Candidate
) then
5891 -- If we know that the unit is a child unit we can give a more
5892 -- accurate error message.
5894 if Is_Child_Unit
(Candidate
) then
5896 -- If the candidate is a private child unit and we are in
5897 -- the visible part of a public unit, specialize the error
5898 -- message. There might be a private with_clause for it,
5899 -- but it is not currently active.
5901 if Is_Private_Descendant
(Candidate
)
5902 and then Ekind
(Current_Scope
) = E_Package
5903 and then not In_Private_Part
(Current_Scope
)
5904 and then not Is_Private_Descendant
(Current_Scope
)
5906 Error_Msg_N
("private child unit& is not visible here",
5909 -- Normal case where we have a missing with for a child unit
5912 Error_Msg_Qual_Level
:= 99;
5913 Error_Msg_NE
-- CODEFIX
5914 ("missing `WITH &;`", Selector
, Candidate
);
5915 Error_Msg_Qual_Level
:= 0;
5918 -- Here we don't know that this is a child unit
5921 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5925 -- Within the instantiation of a child unit, the prefix may
5926 -- denote the parent instance, but the selector has the name
5927 -- of the original child. That is to say, when A.B appears
5928 -- within an instantiation of generic child unit B, the scope
5929 -- stack includes an instance of A (P_Name) and an instance
5930 -- of B under some other name. We scan the scope to find this
5931 -- child instance, which is the desired entity.
5932 -- Note that the parent may itself be a child instance, if
5933 -- the reference is of the form A.B.C, in which case A.B has
5934 -- already been rewritten with the proper entity.
5936 if In_Open_Scopes
(P_Name
)
5937 and then Is_Generic_Instance
(P_Name
)
5940 Gen_Par
: constant Entity_Id
:=
5941 Generic_Parent
(Specification
5942 (Unit_Declaration_Node
(P_Name
)));
5943 S
: Entity_Id
:= Current_Scope
;
5947 for J
in reverse 0 .. Scope_Stack
.Last
loop
5948 S
:= Scope_Stack
.Table
(J
).Entity
;
5950 exit when S
= Standard_Standard
;
5952 if Ekind_In
(S
, E_Function
,
5956 P
:= Generic_Parent
(Specification
5957 (Unit_Declaration_Node
(S
)));
5959 -- Check that P is a generic child of the generic
5960 -- parent of the prefix.
5963 and then Chars
(P
) = Chars
(Selector
)
5964 and then Scope
(P
) = Gen_Par
5975 -- If this is a selection from Ada, System or Interfaces, then
5976 -- we assume a missing with for the corresponding package.
5978 if Is_Known_Unit
(N
) then
5979 if not Error_Posted
(N
) then
5980 Error_Msg_Node_2
:= Selector
;
5981 Error_Msg_N
-- CODEFIX
5982 ("missing `WITH &.&;`", Prefix
(N
));
5985 -- If this is a selection from a dummy package, then suppress
5986 -- the error message, of course the entity is missing if the
5987 -- package is missing.
5989 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
5992 -- Here we have the case of an undefined component
5996 -- The prefix may hide a homonym in the context that
5997 -- declares the desired entity. This error can use a
5998 -- specialized message.
6000 if In_Open_Scopes
(P_Name
) then
6002 H
: constant Entity_Id
:= Homonym
(P_Name
);
6006 and then Is_Compilation_Unit
(H
)
6008 (Is_Immediately_Visible
(H
)
6009 or else Is_Visible_Lib_Unit
(H
))
6011 Id
:= First_Entity
(H
);
6012 while Present
(Id
) loop
6013 if Chars
(Id
) = Chars
(Selector
) then
6014 Error_Msg_Qual_Level
:= 99;
6015 Error_Msg_Name_1
:= Chars
(Selector
);
6017 ("% not declared in&", N
, P_Name
);
6019 ("\use fully qualified name starting with "
6020 & "Standard to make& visible", N
, H
);
6021 Error_Msg_Qual_Level
:= 0;
6029 -- If not found, standard error message
6031 Error_Msg_NE
("& not declared in&", N
, Selector
);
6037 Error_Msg_NE
("& not declared in&", N
, Selector
);
6040 -- Check for misspelling of some entity in prefix
6042 Id
:= First_Entity
(P_Name
);
6043 while Present
(Id
) loop
6044 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6045 and then not Is_Internal_Name
(Chars
(Id
))
6047 Error_Msg_NE
-- CODEFIX
6048 ("possible misspelling of&", Selector
, Id
);
6055 -- Specialize the message if this may be an instantiation
6056 -- of a child unit that was not mentioned in the context.
6058 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6059 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6060 and then Is_Compilation_Unit
6061 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6063 Error_Msg_Node_2
:= Selector
;
6064 Error_Msg_N
-- CODEFIX
6065 ("\missing `WITH &.&;`", Prefix
(N
));
6075 if Comes_From_Source
(N
)
6076 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6077 and then Ekind
(Id
) = E_Access_Subprogram_Type
6078 and then Present
(Equivalent_Type
(Id
))
6080 -- If we are not actually generating distribution code (i.e. the
6081 -- current PCS is the dummy non-distributed version), then the
6082 -- Equivalent_Type will be missing, and Id should be treated as
6083 -- a regular access-to-subprogram type.
6085 Id
:= Equivalent_Type
(Id
);
6086 Set_Chars
(Selector
, Chars
(Id
));
6089 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6091 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6092 if From_Limited_With
(Id
)
6093 or else Is_Type
(Id
)
6094 or else Ekind
(Id
) = E_Package
6099 ("limited withed package can only be used to access "
6100 & "incomplete types", N
);
6104 if Is_Task_Type
(P_Name
)
6105 and then ((Ekind
(Id
) = E_Entry
6106 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6108 (Ekind
(Id
) = E_Entry_Family
6110 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6112 -- If both the task type and the entry are in scope, this may still
6113 -- be the expanded name of an entry formal.
6115 if In_Open_Scopes
(Id
)
6116 and then Nkind
(Parent
(N
)) = N_Selected_Component
6121 -- It is an entry call after all, either to the current task
6122 -- (which will deadlock) or to an enclosing task.
6124 Analyze_Selected_Component
(N
);
6129 Change_Selected_Component_To_Expanded_Name
(N
);
6131 -- Set appropriate type
6133 if Is_Type
(Id
) then
6136 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6139 -- Do style check and generate reference, but skip both steps if this
6140 -- entity has homonyms, since we may not have the right homonym set yet.
6141 -- The proper homonym will be set during the resolve phase.
6143 if Has_Homonym
(Id
) then
6147 Set_Entity_Or_Discriminal
(N
, Id
);
6151 Generate_Reference
(Id
, N
, 'm');
6153 Generate_Reference
(Id
, N
, 'r');
6155 Deferred_References
.Append
((Id
, N
));
6159 -- Check for violation of No_Wide_Characters
6161 Check_Wide_Character_Restriction
(Id
, N
);
6163 -- If the Ekind of the entity is Void, it means that all homonyms are
6164 -- hidden from all visibility (RM 8.3(5,14-20)).
6166 if Ekind
(Id
) = E_Void
then
6167 Premature_Usage
(N
);
6169 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6171 H
: Entity_Id
:= Homonym
(Id
);
6174 while Present
(H
) loop
6175 if Scope
(H
) = Scope
(Id
)
6176 and then (not Is_Hidden
(H
)
6177 or else Is_Immediately_Visible
(H
))
6179 Collect_Interps
(N
);
6186 -- If an extension of System is present, collect possible explicit
6187 -- overloadings declared in the extension.
6189 if Chars
(P_Name
) = Name_System
6190 and then Scope
(P_Name
) = Standard_Standard
6191 and then Present
(System_Extend_Unit
)
6192 and then Present_System_Aux
(N
)
6194 H
:= Current_Entity
(Id
);
6196 while Present
(H
) loop
6197 if Scope
(H
) = System_Aux_Id
then
6198 Add_One_Interp
(N
, H
, Etype
(H
));
6207 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6208 and then Scope
(Id
) /= Standard_Standard
6210 -- In addition to user-defined operators in the given scope, there
6211 -- may be an implicit instance of the predefined operator. The
6212 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6213 -- and added to the interpretations. Procedure Add_One_Interp will
6214 -- determine which hides which.
6216 if Has_Implicit_Operator
(N
) then
6221 -- If there is a single interpretation for N we can generate a
6222 -- reference to the unique entity found.
6224 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6225 Generate_Reference
(Id
, N
);
6227 end Find_Expanded_Name
;
6229 -------------------------
6230 -- Find_Renamed_Entity --
6231 -------------------------
6233 function Find_Renamed_Entity
6237 Is_Actual
: Boolean := False) return Entity_Id
6240 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6246 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6247 -- If the renamed entity is an implicit operator, check whether it is
6248 -- visible because its operand type is properly visible. This check
6249 -- applies to explicit renamed entities that appear in the source in a
6250 -- renaming declaration or a formal subprogram instance, but not to
6251 -- default generic actuals with a name.
6253 function Report_Overload
return Entity_Id
;
6254 -- List possible interpretations, and specialize message in the
6255 -- case of a generic actual.
6257 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6258 -- Determine whether a candidate subprogram is defined within the
6259 -- enclosing instance. If yes, it has precedence over outer candidates.
6261 --------------------------
6262 -- Is_Visible_Operation --
6263 --------------------------
6265 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6271 if Ekind
(Op
) /= E_Operator
6272 or else Scope
(Op
) /= Standard_Standard
6273 or else (In_Instance
6274 and then (not Is_Actual
6275 or else Present
(Enclosing_Instance
)))
6280 -- For a fixed point type operator, check the resulting type,
6281 -- because it may be a mixed mode integer * fixed operation.
6283 if Present
(Next_Formal
(First_Formal
(New_S
)))
6284 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6286 Typ
:= Etype
(New_S
);
6288 Typ
:= Etype
(First_Formal
(New_S
));
6291 Btyp
:= Base_Type
(Typ
);
6293 if Nkind
(Nam
) /= N_Expanded_Name
then
6294 return (In_Open_Scopes
(Scope
(Btyp
))
6295 or else Is_Potentially_Use_Visible
(Btyp
)
6296 or else In_Use
(Btyp
)
6297 or else In_Use
(Scope
(Btyp
)));
6300 Scop
:= Entity
(Prefix
(Nam
));
6302 if Ekind
(Scop
) = E_Package
6303 and then Present
(Renamed_Object
(Scop
))
6305 Scop
:= Renamed_Object
(Scop
);
6308 -- Operator is visible if prefix of expanded name denotes
6309 -- scope of type, or else type is defined in System_Aux
6310 -- and the prefix denotes System.
6312 return Scope
(Btyp
) = Scop
6313 or else (Scope
(Btyp
) = System_Aux_Id
6314 and then Scope
(Scope
(Btyp
)) = Scop
);
6317 end Is_Visible_Operation
;
6323 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6327 Sc
:= Scope
(Inner
);
6328 while Sc
/= Standard_Standard
loop
6339 ---------------------
6340 -- Report_Overload --
6341 ---------------------
6343 function Report_Overload
return Entity_Id
is
6346 Error_Msg_NE
-- CODEFIX
6347 ("ambiguous actual subprogram&, " &
6348 "possible interpretations:", N
, Nam
);
6350 Error_Msg_N
-- CODEFIX
6351 ("ambiguous subprogram, " &
6352 "possible interpretations:", N
);
6355 List_Interps
(Nam
, N
);
6357 end Report_Overload
;
6359 -- Start of processing for Find_Renamed_Entity
6363 Candidate_Renaming
:= Empty
;
6365 if Is_Overloaded
(Nam
) then
6366 Get_First_Interp
(Nam
, Ind
, It
);
6367 while Present
(It
.Nam
) loop
6368 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6369 and then Is_Visible_Operation
(It
.Nam
)
6371 if Old_S
/= Any_Id
then
6373 -- Note: The call to Disambiguate only happens if a
6374 -- previous interpretation was found, in which case I1
6375 -- has received a value.
6377 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6379 if It1
= No_Interp
then
6380 Inst
:= Enclosing_Instance
;
6382 if Present
(Inst
) then
6383 if Within
(It
.Nam
, Inst
) then
6384 if Within
(Old_S
, Inst
) then
6386 -- Choose the innermost subprogram, which would
6387 -- have hidden the outer one in the generic.
6389 if Scope_Depth
(It
.Nam
) <
6398 elsif Within
(Old_S
, Inst
) then
6402 return Report_Overload
;
6405 -- If not within an instance, ambiguity is real
6408 return Report_Overload
;
6422 Present
(First_Formal
(It
.Nam
))
6423 and then Present
(First_Formal
(New_S
))
6424 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6425 Base_Type
(Etype
(First_Formal
(New_S
))))
6427 Candidate_Renaming
:= It
.Nam
;
6430 Get_Next_Interp
(Ind
, It
);
6433 Set_Entity
(Nam
, Old_S
);
6435 if Old_S
/= Any_Id
then
6436 Set_Is_Overloaded
(Nam
, False);
6439 -- Non-overloaded case
6442 if Is_Actual
and then Present
(Enclosing_Instance
) then
6443 Old_S
:= Entity
(Nam
);
6445 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6446 Candidate_Renaming
:= New_S
;
6448 if Is_Visible_Operation
(Entity
(Nam
)) then
6449 Old_S
:= Entity
(Nam
);
6452 elsif Present
(First_Formal
(Entity
(Nam
)))
6453 and then Present
(First_Formal
(New_S
))
6454 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6455 Base_Type
(Etype
(First_Formal
(New_S
))))
6457 Candidate_Renaming
:= Entity
(Nam
);
6462 end Find_Renamed_Entity
;
6464 -----------------------------
6465 -- Find_Selected_Component --
6466 -----------------------------
6468 procedure Find_Selected_Component
(N
: Node_Id
) is
6469 P
: constant Node_Id
:= Prefix
(N
);
6472 -- Entity denoted by prefix
6479 function Available_Subtype
return Boolean;
6480 -- A small optimization: if the prefix is constrained and the component
6481 -- is an array type we may already have a usable subtype for it, so we
6482 -- can use it rather than generating a new one, because the bounds
6483 -- will be the values of the discriminants and not discriminant refs.
6484 -- This simplifies value tracing in GNATProve. For consistency, both
6485 -- the entity name and the subtype come from the constrained component.
6487 function Is_Reference_In_Subunit
return Boolean;
6488 -- In a subunit, the scope depth is not a proper measure of hiding,
6489 -- because the context of the proper body may itself hide entities in
6490 -- parent units. This rare case requires inspecting the tree directly
6491 -- because the proper body is inserted in the main unit and its context
6492 -- is simply added to that of the parent.
6494 -----------------------
6495 -- Available_Subtype --
6496 -----------------------
6498 function Available_Subtype
return Boolean is
6502 Comp
:= First_Entity
(Etype
(P
));
6503 while Present
(Comp
) loop
6504 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6505 Set_Etype
(N
, Etype
(Comp
));
6506 Set_Entity
(Selector_Name
(N
), Comp
);
6507 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6511 Next_Component
(Comp
);
6515 end Available_Subtype
;
6517 -----------------------------
6518 -- Is_Reference_In_Subunit --
6519 -----------------------------
6521 function Is_Reference_In_Subunit
return Boolean is
6523 Comp_Unit
: Node_Id
;
6527 while Present
(Comp_Unit
)
6528 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6530 Comp_Unit
:= Parent
(Comp_Unit
);
6533 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6537 -- Now check whether the package is in the context of the subunit
6539 Clause
:= First
(Context_Items
(Comp_Unit
));
6540 while Present
(Clause
) loop
6541 if Nkind
(Clause
) = N_With_Clause
6542 and then Entity
(Name
(Clause
)) = P_Name
6547 Clause
:= Next
(Clause
);
6551 end Is_Reference_In_Subunit
;
6553 -- Start of processing for Find_Selected_Component
6558 if Nkind
(P
) = N_Error
then
6562 -- Selector name cannot be a character literal or an operator symbol in
6563 -- SPARK, except for the operator symbol in a renaming.
6565 if Restriction_Check_Required
(SPARK_05
) then
6566 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6567 Check_SPARK_05_Restriction
6568 ("character literal cannot be prefixed", N
);
6569 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6570 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6572 Check_SPARK_05_Restriction
6573 ("operator symbol cannot be prefixed", N
);
6577 -- If the selector already has an entity, the node has been constructed
6578 -- in the course of expansion, and is known to be valid. Do not verify
6579 -- that it is defined for the type (it may be a private component used
6580 -- in the expansion of record equality).
6582 if Present
(Entity
(Selector_Name
(N
))) then
6583 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6585 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6586 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6590 Set_Etype
(Sel_Name
, Etype
(Selector
));
6592 if not Is_Entity_Name
(P
) then
6596 -- Build an actual subtype except for the first parameter
6597 -- of an init proc, where this actual subtype is by
6598 -- definition incorrect, since the object is uninitialized
6599 -- (and does not even have defined discriminants etc.)
6601 if Is_Entity_Name
(P
)
6602 and then Ekind
(Entity
(P
)) = E_Function
6604 Nam
:= New_Copy
(P
);
6606 if Is_Overloaded
(P
) then
6607 Save_Interps
(P
, Nam
);
6610 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6612 Analyze_Selected_Component
(N
);
6615 elsif Ekind
(Selector
) = E_Component
6616 and then (not Is_Entity_Name
(P
)
6617 or else Chars
(Entity
(P
)) /= Name_uInit
)
6619 -- Check if we already have an available subtype we can use
6621 if Ekind
(Etype
(P
)) = E_Record_Subtype
6622 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6623 and then Is_Array_Type
(Etype
(Selector
))
6624 and then not Is_Packed
(Etype
(Selector
))
6625 and then Available_Subtype
6629 -- Do not build the subtype when referencing components of
6630 -- dispatch table wrappers. Required to avoid generating
6631 -- elaboration code with HI runtimes. JVM and .NET use a
6632 -- modified version of Ada.Tags which does not contain RE_
6633 -- Dispatch_Table_Wrapper and RE_No_Dispatch_Table_Wrapper.
6634 -- Avoid raising RE_Not_Available exception in those cases.
6636 elsif VM_Target
= No_VM
6637 and then RTU_Loaded
(Ada_Tags
)
6639 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6640 and then Scope
(Selector
) =
6641 RTE
(RE_Dispatch_Table_Wrapper
))
6643 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6644 and then Scope
(Selector
) =
6645 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6650 Build_Actual_Subtype_Of_Component
6651 (Etype
(Selector
), N
);
6658 if No
(C_Etype
) then
6659 C_Etype
:= Etype
(Selector
);
6661 Insert_Action
(N
, C_Etype
);
6662 C_Etype
:= Defining_Identifier
(C_Etype
);
6665 Set_Etype
(N
, C_Etype
);
6668 -- If this is the name of an entry or protected operation, and
6669 -- the prefix is an access type, insert an explicit dereference,
6670 -- so that entry calls are treated uniformly.
6672 if Is_Access_Type
(Etype
(P
))
6673 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6676 New_P
: constant Node_Id
:=
6677 Make_Explicit_Dereference
(Sloc
(P
),
6678 Prefix
=> Relocate_Node
(P
));
6681 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6685 -- If the selected component appears within a default expression
6686 -- and it has an actual subtype, the pre-analysis has not yet
6687 -- completed its analysis, because Insert_Actions is disabled in
6688 -- that context. Within the init proc of the enclosing type we
6689 -- must complete this analysis, if an actual subtype was created.
6691 elsif Inside_Init_Proc
then
6693 Typ
: constant Entity_Id
:= Etype
(N
);
6694 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6696 if Nkind
(Decl
) = N_Subtype_Declaration
6697 and then not Analyzed
(Decl
)
6698 and then Is_List_Member
(Decl
)
6699 and then No
(Parent
(Decl
))
6702 Insert_Action
(N
, Decl
);
6709 elsif Is_Entity_Name
(P
) then
6710 P_Name
:= Entity
(P
);
6712 -- The prefix may denote an enclosing type which is the completion
6713 -- of an incomplete type declaration.
6715 if Is_Type
(P_Name
) then
6716 Set_Entity
(P
, Get_Full_View
(P_Name
));
6717 Set_Etype
(P
, Entity
(P
));
6718 P_Name
:= Entity
(P
);
6721 P_Type
:= Base_Type
(Etype
(P
));
6723 if Debug_Flag_E
then
6724 Write_Str
("Found prefix type to be ");
6725 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6728 -- The designated type may be a limited view with no components.
6729 -- Check whether the non-limited view is available, because in some
6730 -- cases this will not be set when installing the context.
6732 if Is_Access_Type
(P_Type
) then
6734 D
: constant Entity_Id
:= Directly_Designated_Type
(P_Type
);
6736 if Is_Incomplete_Type
(D
)
6737 and then From_Limited_With
(D
)
6738 and then Present
(Non_Limited_View
(D
))
6740 Set_Directly_Designated_Type
(P_Type
, Non_Limited_View
(D
));
6745 -- First check for components of a record object (not the
6746 -- result of a call, which is handled below).
6748 if Is_Appropriate_For_Record
(P_Type
)
6749 and then not Is_Overloadable
(P_Name
)
6750 and then not Is_Type
(P_Name
)
6752 -- Selected component of record. Type checking will validate
6753 -- name of selector.
6755 -- ??? Could we rewrite an implicit dereference into an explicit
6758 Analyze_Selected_Component
(N
);
6760 -- Reference to type name in predicate/invariant expression
6762 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6763 and then not In_Open_Scopes
(P_Name
)
6764 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6765 or else not In_Open_Scopes
(Etype
(P_Name
)))
6767 -- Call to protected operation or entry. Type checking is
6768 -- needed on the prefix.
6770 Analyze_Selected_Component
(N
);
6772 elsif (In_Open_Scopes
(P_Name
)
6773 and then Ekind
(P_Name
) /= E_Void
6774 and then not Is_Overloadable
(P_Name
))
6775 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6776 and then In_Open_Scopes
(Etype
(P_Name
)))
6778 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6779 -- enclosing construct that is not a subprogram or accept.
6781 Find_Expanded_Name
(N
);
6783 elsif Ekind
(P_Name
) = E_Package
then
6784 Find_Expanded_Name
(N
);
6786 elsif Is_Overloadable
(P_Name
) then
6788 -- The subprogram may be a renaming (of an enclosing scope) as
6789 -- in the case of the name of the generic within an instantiation.
6791 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6792 and then Present
(Alias
(P_Name
))
6793 and then Is_Generic_Instance
(Alias
(P_Name
))
6795 P_Name
:= Alias
(P_Name
);
6798 if Is_Overloaded
(P
) then
6800 -- The prefix must resolve to a unique enclosing construct
6803 Found
: Boolean := False;
6808 Get_First_Interp
(P
, Ind
, It
);
6809 while Present
(It
.Nam
) loop
6810 if In_Open_Scopes
(It
.Nam
) then
6813 "prefix must be unique enclosing scope", N
);
6814 Set_Entity
(N
, Any_Id
);
6815 Set_Etype
(N
, Any_Type
);
6824 Get_Next_Interp
(Ind
, It
);
6829 if In_Open_Scopes
(P_Name
) then
6830 Set_Entity
(P
, P_Name
);
6831 Set_Is_Overloaded
(P
, False);
6832 Find_Expanded_Name
(N
);
6835 -- If no interpretation as an expanded name is possible, it
6836 -- must be a selected component of a record returned by a
6837 -- function call. Reformat prefix as a function call, the rest
6838 -- is done by type resolution.
6840 -- Error if the prefix is procedure or entry, as is P.X
6842 if Ekind
(P_Name
) /= E_Function
6844 (not Is_Overloaded
(P
)
6845 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6847 -- Prefix may mention a package that is hidden by a local
6848 -- declaration: let the user know. Scan the full homonym
6849 -- chain, the candidate package may be anywhere on it.
6851 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6852 P_Name
:= Current_Entity
(P_Name
);
6854 while Present
(P_Name
) loop
6855 exit when Ekind
(P_Name
) = E_Package
;
6856 P_Name
:= Homonym
(P_Name
);
6859 if Present
(P_Name
) then
6860 if not Is_Reference_In_Subunit
then
6861 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6863 ("package& is hidden by declaration#", N
, P_Name
);
6866 Set_Entity
(Prefix
(N
), P_Name
);
6867 Find_Expanded_Name
(N
);
6871 P_Name
:= Entity
(Prefix
(N
));
6876 ("invalid prefix in selected component&", N
, P_Name
);
6877 Change_Selected_Component_To_Expanded_Name
(N
);
6878 Set_Entity
(N
, Any_Id
);
6879 Set_Etype
(N
, Any_Type
);
6881 -- Here we have a function call, so do the reformatting
6884 Nam
:= New_Copy
(P
);
6885 Save_Interps
(P
, Nam
);
6887 -- We use Replace here because this is one of those cases
6888 -- where the parser has missclassified the node, and we
6889 -- fix things up and then do the semantic analysis on the
6890 -- fixed up node. Normally we do this using one of the
6891 -- Sinfo.CN routines, but this is too tricky for that.
6893 -- Note that using Rewrite would be wrong, because we
6894 -- would have a tree where the original node is unanalyzed,
6895 -- and this violates the required interface for ASIS.
6898 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6900 -- Now analyze the reformatted node
6903 Analyze_Selected_Component
(N
);
6907 -- Remaining cases generate various error messages
6910 -- Format node as expanded name, to avoid cascaded errors
6912 Change_Selected_Component_To_Expanded_Name
(N
);
6913 Set_Entity
(N
, Any_Id
);
6914 Set_Etype
(N
, Any_Type
);
6916 -- Issue error message, but avoid this if error issued already.
6917 -- Use identifier of prefix if one is available.
6919 if P_Name
= Any_Id
then
6922 elsif Ekind
(P_Name
) = E_Void
then
6923 Premature_Usage
(P
);
6925 elsif Nkind
(P
) /= N_Attribute_Reference
then
6927 -- This may have been meant as a prefixed call to a primitive
6928 -- of an untagged type.
6931 F
: constant Entity_Id
:=
6932 Current_Entity
(Selector_Name
(N
));
6935 and then Is_Overloadable
(F
)
6936 and then Present
(First_Entity
(F
))
6937 and then Etype
(First_Entity
(F
)) = Etype
(P
)
6938 and then not Is_Tagged_Type
(Etype
(P
))
6941 ("prefixed call is only allowed for objects "
6942 & "of a tagged type", N
);
6946 Error_Msg_N
("invalid prefix in selected component&", P
);
6948 if Is_Access_Type
(P_Type
)
6949 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
6952 ("\dereference must not be of an incomplete type "
6953 & "(RM 3.10.1)", P
);
6957 Error_Msg_N
("invalid prefix in selected component", P
);
6961 -- Selector name is restricted in SPARK
6963 if Nkind
(N
) = N_Expanded_Name
6964 and then Restriction_Check_Required
(SPARK_05
)
6966 if Is_Subprogram
(P_Name
) then
6967 Check_SPARK_05_Restriction
6968 ("prefix of expanded name cannot be a subprogram", P
);
6969 elsif Ekind
(P_Name
) = E_Loop
then
6970 Check_SPARK_05_Restriction
6971 ("prefix of expanded name cannot be a loop statement", P
);
6976 -- If prefix is not the name of an entity, it must be an expression,
6977 -- whose type is appropriate for a record. This is determined by
6980 Analyze_Selected_Component
(N
);
6983 Analyze_Dimension
(N
);
6984 end Find_Selected_Component
;
6990 procedure Find_Type
(N
: Node_Id
) is
7000 elsif Nkind
(N
) = N_Attribute_Reference
then
7002 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7003 -- need to enforce that at this point, since the declaration of the
7004 -- tagged type in the prefix would have been flagged already.
7006 if Attribute_Name
(N
) = Name_Class
then
7007 Check_Restriction
(No_Dispatch
, N
);
7008 Find_Type
(Prefix
(N
));
7010 -- Propagate error from bad prefix
7012 if Etype
(Prefix
(N
)) = Any_Type
then
7013 Set_Entity
(N
, Any_Type
);
7014 Set_Etype
(N
, Any_Type
);
7018 T
:= Base_Type
(Entity
(Prefix
(N
)));
7020 -- Case where type is not known to be tagged. Its appearance in
7021 -- the prefix of the 'Class attribute indicates that the full view
7024 if not Is_Tagged_Type
(T
) then
7025 if Ekind
(T
) = E_Incomplete_Type
then
7027 -- It is legal to denote the class type of an incomplete
7028 -- type. The full type will have to be tagged, of course.
7029 -- In Ada 2005 this usage is declared obsolescent, so we
7030 -- warn accordingly. This usage is only legal if the type
7031 -- is completed in the current scope, and not for a limited
7034 if Ada_Version
>= Ada_2005
then
7036 -- Test whether the Available_View of a limited type view
7037 -- is tagged, since the limited view may not be marked as
7038 -- tagged if the type itself has an untagged incomplete
7039 -- type view in its package.
7041 if From_Limited_With
(T
)
7042 and then not Is_Tagged_Type
(Available_View
(T
))
7045 ("prefix of Class attribute must be tagged", N
);
7046 Set_Etype
(N
, Any_Type
);
7047 Set_Entity
(N
, Any_Type
);
7050 -- ??? This test is temporarily disabled (always
7051 -- False) because it causes an unwanted warning on
7052 -- GNAT sources (built with -gnatg, which includes
7053 -- Warn_On_Obsolescent_ Feature). Once this issue
7054 -- is cleared in the sources, it can be enabled.
7056 elsif Warn_On_Obsolescent_Feature
and then False then
7058 ("applying 'Class to an untagged incomplete type"
7059 & " is an obsolescent feature (RM J.11)?r?", N
);
7063 Set_Is_Tagged_Type
(T
);
7064 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7065 Make_Class_Wide_Type
(T
);
7066 Set_Entity
(N
, Class_Wide_Type
(T
));
7067 Set_Etype
(N
, Class_Wide_Type
(T
));
7069 elsif Ekind
(T
) = E_Private_Type
7070 and then not Is_Generic_Type
(T
)
7071 and then In_Private_Part
(Scope
(T
))
7073 -- The Class attribute can be applied to an untagged private
7074 -- type fulfilled by a tagged type prior to the full type
7075 -- declaration (but only within the parent package's private
7076 -- part). Create the class-wide type now and check that the
7077 -- full type is tagged later during its analysis. Note that
7078 -- we do not mark the private type as tagged, unlike the
7079 -- case of incomplete types, because the type must still
7080 -- appear untagged to outside units.
7082 if No
(Class_Wide_Type
(T
)) then
7083 Make_Class_Wide_Type
(T
);
7086 Set_Entity
(N
, Class_Wide_Type
(T
));
7087 Set_Etype
(N
, Class_Wide_Type
(T
));
7090 -- Should we introduce a type Any_Tagged and use Wrong_Type
7091 -- here, it would be a bit more consistent???
7094 ("tagged type required, found}",
7095 Prefix
(N
), First_Subtype
(T
));
7096 Set_Entity
(N
, Any_Type
);
7100 -- Case of tagged type
7103 if Is_Concurrent_Type
(T
) then
7104 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7106 -- Previous error. Use current type, which at least
7107 -- provides some operations.
7109 C
:= Entity
(Prefix
(N
));
7112 C
:= Class_Wide_Type
7113 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7117 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7120 Set_Entity_With_Checks
(N
, C
);
7121 Generate_Reference
(C
, N
);
7125 -- Base attribute, not allowed in Ada 83
7127 elsif Attribute_Name
(N
) = Name_Base
then
7128 Error_Msg_Name_1
:= Name_Base
;
7129 Check_SPARK_05_Restriction
7130 ("attribute% is only allowed as prefix of another attribute", N
);
7132 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7134 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7137 Find_Type
(Prefix
(N
));
7138 Typ
:= Entity
(Prefix
(N
));
7140 if Ada_Version
>= Ada_95
7141 and then not Is_Scalar_Type
(Typ
)
7142 and then not Is_Generic_Type
(Typ
)
7145 ("prefix of Base attribute must be scalar type",
7148 elsif Warn_On_Redundant_Constructs
7149 and then Base_Type
(Typ
) = Typ
7151 Error_Msg_NE
-- CODEFIX
7152 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7155 T
:= Base_Type
(Typ
);
7157 -- Rewrite attribute reference with type itself (see similar
7158 -- processing in Analyze_Attribute, case Base). Preserve prefix
7159 -- if present, for other legality checks.
7161 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7163 Make_Expanded_Name
(Sloc
(N
),
7165 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7166 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7169 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7176 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7178 -- This is handled in Analyze_Attribute
7182 -- All other attributes are invalid in a subtype mark
7185 Error_Msg_N
("invalid attribute in subtype mark", N
);
7191 if Is_Entity_Name
(N
) then
7192 T_Name
:= Entity
(N
);
7194 Error_Msg_N
("subtype mark required in this context", N
);
7195 Set_Etype
(N
, Any_Type
);
7199 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7201 -- Undefined id. Make it into a valid type
7203 Set_Entity
(N
, Any_Type
);
7205 elsif not Is_Type
(T_Name
)
7206 and then T_Name
/= Standard_Void_Type
7208 Error_Msg_Sloc
:= Sloc
(T_Name
);
7209 Error_Msg_N
("subtype mark required in this context", N
);
7210 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7211 Set_Entity
(N
, Any_Type
);
7214 -- If the type is an incomplete type created to handle
7215 -- anonymous access components of a record type, then the
7216 -- incomplete type is the visible entity and subsequent
7217 -- references will point to it. Mark the original full
7218 -- type as referenced, to prevent spurious warnings.
7220 if Is_Incomplete_Type
(T_Name
)
7221 and then Present
(Full_View
(T_Name
))
7222 and then not Comes_From_Source
(T_Name
)
7224 Set_Referenced
(Full_View
(T_Name
));
7227 T_Name
:= Get_Full_View
(T_Name
);
7229 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7230 -- limited-with clauses
7232 if From_Limited_With
(T_Name
)
7233 and then Ekind
(T_Name
) in Incomplete_Kind
7234 and then Present
(Non_Limited_View
(T_Name
))
7235 and then Is_Interface
(Non_Limited_View
(T_Name
))
7237 T_Name
:= Non_Limited_View
(T_Name
);
7240 if In_Open_Scopes
(T_Name
) then
7241 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7243 -- In Ada 2005, a task name can be used in an access
7244 -- definition within its own body. It cannot be used
7245 -- in the discriminant part of the task declaration,
7246 -- nor anywhere else in the declaration because entries
7247 -- cannot have access parameters.
7249 if Ada_Version
>= Ada_2005
7250 and then Nkind
(Parent
(N
)) = N_Access_Definition
7252 Set_Entity
(N
, T_Name
);
7253 Set_Etype
(N
, T_Name
);
7255 if Has_Completion
(T_Name
) then
7260 ("task type cannot be used as type mark " &
7261 "within its own declaration", N
);
7266 ("task type cannot be used as type mark " &
7267 "within its own spec or body", N
);
7270 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7272 -- In Ada 2005, a protected name can be used in an access
7273 -- definition within its own body.
7275 if Ada_Version
>= Ada_2005
7276 and then Nkind
(Parent
(N
)) = N_Access_Definition
7278 Set_Entity
(N
, T_Name
);
7279 Set_Etype
(N
, T_Name
);
7284 ("protected type cannot be used as type mark " &
7285 "within its own spec or body", N
);
7289 Error_Msg_N
("type declaration cannot refer to itself", N
);
7292 Set_Etype
(N
, Any_Type
);
7293 Set_Entity
(N
, Any_Type
);
7294 Set_Error_Posted
(T_Name
);
7298 Set_Entity
(N
, T_Name
);
7299 Set_Etype
(N
, T_Name
);
7303 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7304 if Is_Fixed_Point_Type
(Etype
(N
)) then
7305 Check_Restriction
(No_Fixed_Point
, N
);
7306 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7307 Check_Restriction
(No_Floating_Point
, N
);
7310 -- A Ghost type must appear in a specific context
7312 if Is_Ghost_Entity
(Etype
(N
)) then
7313 Check_Ghost_Context
(Etype
(N
), N
);
7318 ------------------------------------
7319 -- Has_Implicit_Character_Literal --
7320 ------------------------------------
7322 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7324 Found
: Boolean := False;
7325 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7326 Priv_Id
: Entity_Id
:= Empty
;
7329 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7330 Priv_Id
:= First_Private_Entity
(P
);
7333 if P
= Standard_Standard
then
7334 Change_Selected_Component_To_Expanded_Name
(N
);
7335 Rewrite
(N
, Selector_Name
(N
));
7337 Set_Etype
(Original_Node
(N
), Standard_Character
);
7341 Id
:= First_Entity
(P
);
7342 while Present
(Id
) and then Id
/= Priv_Id
loop
7343 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7345 -- We replace the node with the literal itself, resolve as a
7346 -- character, and set the type correctly.
7349 Change_Selected_Component_To_Expanded_Name
(N
);
7350 Rewrite
(N
, Selector_Name
(N
));
7353 Set_Etype
(Original_Node
(N
), Id
);
7357 -- More than one type derived from Character in given scope.
7358 -- Collect all possible interpretations.
7360 Add_One_Interp
(N
, Id
, Id
);
7368 end Has_Implicit_Character_Literal
;
7370 ----------------------
7371 -- Has_Private_With --
7372 ----------------------
7374 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7375 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7379 Item
:= First
(Context_Items
(Comp_Unit
));
7380 while Present
(Item
) loop
7381 if Nkind
(Item
) = N_With_Clause
7382 and then Private_Present
(Item
)
7383 and then Entity
(Name
(Item
)) = E
7392 end Has_Private_With
;
7394 ---------------------------
7395 -- Has_Implicit_Operator --
7396 ---------------------------
7398 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7399 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7400 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7402 Priv_Id
: Entity_Id
:= Empty
;
7404 procedure Add_Implicit_Operator
7406 Op_Type
: Entity_Id
:= Empty
);
7407 -- Add implicit interpretation to node N, using the type for which a
7408 -- predefined operator exists. If the operator yields a boolean type,
7409 -- the Operand_Type is implicitly referenced by the operator, and a
7410 -- reference to it must be generated.
7412 ---------------------------
7413 -- Add_Implicit_Operator --
7414 ---------------------------
7416 procedure Add_Implicit_Operator
7418 Op_Type
: Entity_Id
:= Empty
)
7420 Predef_Op
: Entity_Id
;
7423 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7424 while Present
(Predef_Op
)
7425 and then Scope
(Predef_Op
) /= Standard_Standard
7427 Predef_Op
:= Homonym
(Predef_Op
);
7430 if Nkind
(N
) = N_Selected_Component
then
7431 Change_Selected_Component_To_Expanded_Name
(N
);
7434 -- If the context is an unanalyzed function call, determine whether
7435 -- a binary or unary interpretation is required.
7437 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7439 Is_Binary_Call
: constant Boolean :=
7441 (Next
(First
(Expressions
(Parent
(N
)))));
7442 Is_Binary_Op
: constant Boolean :=
7444 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7445 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7448 if Is_Binary_Call
then
7449 if Is_Binary_Op
then
7450 Add_One_Interp
(N
, Predef_Op
, T
);
7452 Add_One_Interp
(N
, Predef_Op2
, T
);
7456 if not Is_Binary_Op
then
7457 Add_One_Interp
(N
, Predef_Op
, T
);
7459 Add_One_Interp
(N
, Predef_Op2
, T
);
7465 Add_One_Interp
(N
, Predef_Op
, T
);
7467 -- For operators with unary and binary interpretations, if
7468 -- context is not a call, add both
7470 if Present
(Homonym
(Predef_Op
)) then
7471 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7475 -- The node is a reference to a predefined operator, and
7476 -- an implicit reference to the type of its operands.
7478 if Present
(Op_Type
) then
7479 Generate_Operator_Reference
(N
, Op_Type
);
7481 Generate_Operator_Reference
(N
, T
);
7483 end Add_Implicit_Operator
;
7485 -- Start of processing for Has_Implicit_Operator
7488 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7489 Priv_Id
:= First_Private_Entity
(P
);
7492 Id
:= First_Entity
(P
);
7496 -- Boolean operators: an implicit declaration exists if the scope
7497 -- contains a declaration for a derived Boolean type, or for an
7498 -- array of Boolean type.
7500 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7501 while Id
/= Priv_Id
loop
7502 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7503 Add_Implicit_Operator
(Id
);
7510 -- Equality: look for any non-limited type (result is Boolean)
7512 when Name_Op_Eq | Name_Op_Ne
=>
7513 while Id
/= Priv_Id
loop
7515 and then not Is_Limited_Type
(Id
)
7516 and then Is_Base_Type
(Id
)
7518 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7525 -- Comparison operators: scalar type, or array of scalar
7527 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7528 while Id
/= Priv_Id
loop
7529 if (Is_Scalar_Type
(Id
)
7530 or else (Is_Array_Type
(Id
)
7531 and then Is_Scalar_Type
(Component_Type
(Id
))))
7532 and then Is_Base_Type
(Id
)
7534 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7541 -- Arithmetic operators: any numeric type
7551 while Id
/= Priv_Id
loop
7552 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7553 Add_Implicit_Operator
(Id
);
7560 -- Concatenation: any one-dimensional array type
7562 when Name_Op_Concat
=>
7563 while Id
/= Priv_Id
loop
7564 if Is_Array_Type
(Id
)
7565 and then Number_Dimensions
(Id
) = 1
7566 and then Is_Base_Type
(Id
)
7568 Add_Implicit_Operator
(Id
);
7575 -- What is the others condition here? Should we be using a
7576 -- subtype of Name_Id that would restrict to operators ???
7578 when others => null;
7581 -- If we fall through, then we do not have an implicit operator
7585 end Has_Implicit_Operator
;
7587 -----------------------------------
7588 -- Has_Loop_In_Inner_Open_Scopes --
7589 -----------------------------------
7591 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7593 -- Several scope stacks are maintained by Scope_Stack. The base of the
7594 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7595 -- flag in the scope stack entry. Note that the scope stacks used to
7596 -- simply be delimited implicitly by the presence of Standard_Standard
7597 -- at their base, but there now are cases where this is not sufficient
7598 -- because Standard_Standard actually may appear in the middle of the
7599 -- active set of scopes.
7601 for J
in reverse 0 .. Scope_Stack
.Last
loop
7603 -- S was reached without seing a loop scope first
7605 if Scope_Stack
.Table
(J
).Entity
= S
then
7608 -- S was not yet reached, so it contains at least one inner loop
7610 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7614 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7615 -- cases where Standard_Standard appears in the middle of the active
7616 -- set of scopes. This affects the declaration and overriding of
7617 -- private inherited operations in instantiations of generic child
7620 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7623 raise Program_Error
; -- unreachable
7624 end Has_Loop_In_Inner_Open_Scopes
;
7626 --------------------
7627 -- In_Open_Scopes --
7628 --------------------
7630 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7632 -- Several scope stacks are maintained by Scope_Stack. The base of the
7633 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7634 -- flag in the scope stack entry. Note that the scope stacks used to
7635 -- simply be delimited implicitly by the presence of Standard_Standard
7636 -- at their base, but there now are cases where this is not sufficient
7637 -- because Standard_Standard actually may appear in the middle of the
7638 -- active set of scopes.
7640 for J
in reverse 0 .. Scope_Stack
.Last
loop
7641 if Scope_Stack
.Table
(J
).Entity
= S
then
7645 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7646 -- cases where Standard_Standard appears in the middle of the active
7647 -- set of scopes. This affects the declaration and overriding of
7648 -- private inherited operations in instantiations of generic child
7651 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7657 -----------------------------
7658 -- Inherit_Renamed_Profile --
7659 -----------------------------
7661 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7668 if Ekind
(Old_S
) = E_Operator
then
7669 New_F
:= First_Formal
(New_S
);
7671 while Present
(New_F
) loop
7672 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7673 Next_Formal
(New_F
);
7676 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7679 New_F
:= First_Formal
(New_S
);
7680 Old_F
:= First_Formal
(Old_S
);
7682 while Present
(New_F
) loop
7683 New_T
:= Etype
(New_F
);
7684 Old_T
:= Etype
(Old_F
);
7686 -- If the new type is a renaming of the old one, as is the
7687 -- case for actuals in instances, retain its name, to simplify
7688 -- later disambiguation.
7690 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7691 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7692 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7696 Set_Etype
(New_F
, Old_T
);
7699 Next_Formal
(New_F
);
7700 Next_Formal
(Old_F
);
7703 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7704 Set_Etype
(New_S
, Etype
(Old_S
));
7707 end Inherit_Renamed_Profile
;
7713 procedure Initialize
is
7718 -------------------------
7719 -- Install_Use_Clauses --
7720 -------------------------
7722 procedure Install_Use_Clauses
7724 Force_Installation
: Boolean := False)
7732 while Present
(U
) loop
7734 -- Case of USE package
7736 if Nkind
(U
) = N_Use_Package_Clause
then
7737 P
:= First
(Names
(U
));
7738 while Present
(P
) loop
7741 if Ekind
(Id
) = E_Package
then
7743 Note_Redundant_Use
(P
);
7745 elsif Present
(Renamed_Object
(Id
))
7746 and then In_Use
(Renamed_Object
(Id
))
7748 Note_Redundant_Use
(P
);
7750 elsif Force_Installation
or else Applicable_Use
(P
) then
7751 Use_One_Package
(Id
, U
);
7762 P
:= First
(Subtype_Marks
(U
));
7763 while Present
(P
) loop
7764 if not Is_Entity_Name
(P
)
7765 or else No
(Entity
(P
))
7769 elsif Entity
(P
) /= Any_Type
then
7777 Next_Use_Clause
(U
);
7779 end Install_Use_Clauses
;
7781 -------------------------------------
7782 -- Is_Appropriate_For_Entry_Prefix --
7783 -------------------------------------
7785 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7786 P_Type
: Entity_Id
:= T
;
7789 if Is_Access_Type
(P_Type
) then
7790 P_Type
:= Designated_Type
(P_Type
);
7793 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7794 end Is_Appropriate_For_Entry_Prefix
;
7796 -------------------------------
7797 -- Is_Appropriate_For_Record --
7798 -------------------------------
7800 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7802 function Has_Components
(T1
: Entity_Id
) return Boolean;
7803 -- Determine if given type has components (i.e. is either a record
7804 -- type or a type that has discriminants).
7806 --------------------
7807 -- Has_Components --
7808 --------------------
7810 function Has_Components
(T1
: Entity_Id
) return Boolean is
7812 return Is_Record_Type
(T1
)
7813 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7814 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7815 or else (Is_Incomplete_Type
(T1
)
7816 and then From_Limited_With
(T1
)
7817 and then Present
(Non_Limited_View
(T1
))
7818 and then Is_Record_Type
7819 (Get_Full_View
(Non_Limited_View
(T1
))));
7822 -- Start of processing for Is_Appropriate_For_Record
7827 and then (Has_Components
(T
)
7828 or else (Is_Access_Type
(T
)
7829 and then Has_Components
(Designated_Type
(T
))));
7830 end Is_Appropriate_For_Record
;
7832 ------------------------
7833 -- Note_Redundant_Use --
7834 ------------------------
7836 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7837 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7838 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7839 Decl
: constant Node_Id
:= Parent
(Clause
);
7841 Prev_Use
: Node_Id
:= Empty
;
7842 Redundant
: Node_Id
:= Empty
;
7843 -- The Use_Clause which is actually redundant. In the simplest case it
7844 -- is Pack itself, but when we compile a body we install its context
7845 -- before that of its spec, in which case it is the use_clause in the
7846 -- spec that will appear to be redundant, and we want the warning to be
7847 -- placed on the body. Similar complications appear when the redundancy
7848 -- is between a child unit and one of its ancestors.
7851 Set_Redundant_Use
(Clause
, True);
7853 if not Comes_From_Source
(Clause
)
7855 or else not Warn_On_Redundant_Constructs
7860 if not Is_Compilation_Unit
(Current_Scope
) then
7862 -- If the use_clause is in an inner scope, it is made redundant by
7863 -- some clause in the current context, with one exception: If we're
7864 -- compiling a nested package body, and the use_clause comes from the
7865 -- corresponding spec, the clause is not necessarily fully redundant,
7866 -- so we should not warn. If a warning was warranted, it would have
7867 -- been given when the spec was processed.
7869 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7871 Package_Spec_Entity
: constant Entity_Id
:=
7872 Defining_Unit_Name
(Parent
(Decl
));
7874 if In_Package_Body
(Package_Spec_Entity
) then
7880 Redundant
:= Clause
;
7881 Prev_Use
:= Cur_Use
;
7883 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7885 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7886 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7890 if Cur_Unit
= New_Unit
then
7892 -- Redundant clause in same body
7894 Redundant
:= Clause
;
7895 Prev_Use
:= Cur_Use
;
7897 elsif Cur_Unit
= Current_Sem_Unit
then
7899 -- If the new clause is not in the current unit it has been
7900 -- analyzed first, and it makes the other one redundant.
7901 -- However, if the new clause appears in a subunit, Cur_Unit
7902 -- is still the parent, and in that case the redundant one
7903 -- is the one appearing in the subunit.
7905 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7906 Redundant
:= Clause
;
7907 Prev_Use
:= Cur_Use
;
7909 -- Most common case: redundant clause in body,
7910 -- original clause in spec. Current scope is spec entity.
7915 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7917 Redundant
:= Cur_Use
;
7921 -- The new clause may appear in an unrelated unit, when
7922 -- the parents of a generic are being installed prior to
7923 -- instantiation. In this case there must be no warning.
7924 -- We detect this case by checking whether the current top
7925 -- of the stack is related to the current compilation.
7927 Scop
:= Current_Scope
;
7928 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7929 if Is_Compilation_Unit
(Scop
)
7930 and then not Is_Child_Unit
(Scop
)
7934 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7938 Scop
:= Scope
(Scop
);
7941 Redundant
:= Cur_Use
;
7945 elsif New_Unit
= Current_Sem_Unit
then
7946 Redundant
:= Clause
;
7947 Prev_Use
:= Cur_Use
;
7950 -- Neither is the current unit, so they appear in parent or
7951 -- sibling units. Warning will be emitted elsewhere.
7957 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
7958 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
7960 -- Use_clause is in child unit of current unit, and the child unit
7961 -- appears in the context of the body of the parent, so it has been
7962 -- installed first, even though it is the redundant one. Depending on
7963 -- their placement in the context, the visible or the private parts
7964 -- of the two units, either might appear as redundant, but the
7965 -- message has to be on the current unit.
7967 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
7968 Redundant
:= Cur_Use
;
7971 Redundant
:= Clause
;
7972 Prev_Use
:= Cur_Use
;
7975 -- If the new use clause appears in the private part of a parent unit
7976 -- it may appear to be redundant w.r.t. a use clause in a child unit,
7977 -- but the previous use clause was needed in the visible part of the
7978 -- child, and no warning should be emitted.
7980 if Nkind
(Parent
(Decl
)) = N_Package_Specification
7982 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
7985 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
7986 Spec
: constant Node_Id
:=
7987 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
7990 if Is_Compilation_Unit
(Par
)
7991 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
7992 and then Parent
(Cur_Use
) = Spec
7994 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
8001 -- Finally, if the current use clause is in the context then
8002 -- the clause is redundant when it is nested within the unit.
8004 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
8005 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
8006 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
8008 Redundant
:= Clause
;
8009 Prev_Use
:= Cur_Use
;
8015 if Present
(Redundant
) then
8016 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
8017 Error_Msg_NE
-- CODEFIX
8018 ("& is already use-visible through previous use clause #??",
8019 Redundant
, Pack_Name
);
8021 end Note_Redundant_Use
;
8027 procedure Pop_Scope
is
8028 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8029 S
: constant Entity_Id
:= SST
.Entity
;
8032 if Debug_Flag_E
then
8036 -- Set Default_Storage_Pool field of the library unit if necessary
8038 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8040 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8043 Aux
: constant Node_Id
:=
8044 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8046 if No
(Default_Storage_Pool
(Aux
)) then
8047 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8052 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8053 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8054 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8055 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8056 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8057 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8058 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8059 Default_SSO
:= SST
.Save_Default_SSO
;
8060 Uneval_Old
:= SST
.Save_Uneval_Old
;
8062 if Debug_Flag_W
then
8063 Write_Str
("<-- exiting scope: ");
8064 Write_Name
(Chars
(Current_Scope
));
8065 Write_Str
(", Depth=");
8066 Write_Int
(Int
(Scope_Stack
.Last
));
8070 End_Use_Clauses
(SST
.First_Use_Clause
);
8072 -- If the actions to be wrapped are still there they will get lost
8073 -- causing incomplete code to be generated. It is better to abort in
8074 -- this case (and we do the abort even with assertions off since the
8075 -- penalty is incorrect code generation).
8077 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8078 raise Program_Error;
8081 -- Free last subprogram name if allocated, and pop scope
8083 Free (SST.Last_Subprogram_Name);
8084 Scope_Stack.Decrement_Last;
8091 procedure Push_Scope (S : Entity_Id) is
8092 E : constant Entity_Id := Scope (S);
8095 if Ekind (S) = E_Void then
8098 -- Set scope depth if not a non-concurrent type, and we have not yet set
8099 -- the scope depth. This means that we have the first occurrence of the
8100 -- scope, and this is where the depth is set.
8102 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8103 and then not Scope_Depth_Set (S)
8105 if S = Standard_Standard then
8106 Set_Scope_Depth_Value (S, Uint_0);
8108 elsif Is_Child_Unit (S) then
8109 Set_Scope_Depth_Value (S, Uint_1);
8111 elsif not Is_Record_Type (Current_Scope) then
8112 if Ekind (S) = E_Loop then
8113 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8115 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8120 Scope_Stack.Increment_Last;
8123 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8127 SST.Save_Scope_Suppress := Scope_Suppress;
8128 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8129 SST.Save_Check_Policy_List := Check_Policy_List;
8130 SST.Save_Default_Storage_Pool := Default_Pool;
8131 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8132 SST.Save_SPARK_Mode := SPARK_Mode;
8133 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8134 SST.Save_Default_SSO := Default_SSO;
8135 SST.Save_Uneval_Old := Uneval_Old;
8137 if Scope_Stack.Last > Scope_Stack.First then
8138 SST.Component_Alignment_Default := Scope_Stack.Table
8139 (Scope_Stack.Last - 1).
8140 Component_Alignment_Default;
8143 SST.Last_Subprogram_Name := null;
8144 SST.Is_Transient := False;
8145 SST.Node_To_Be_Wrapped := Empty;
8146 SST.Pending_Freeze_Actions := No_List;
8147 SST.Actions_To_Be_Wrapped := (others => No_List);
8148 SST.First_Use_Clause := Empty;
8149 SST.Is_Active_Stack_Base := False;
8150 SST.Previous_Visibility := False;
8151 SST.Locked_Shared_Objects := No_Elist;
8154 if Debug_Flag_W then
8155 Write_Str ("--> new scope: ");
8156 Write_Name (Chars (Current_Scope));
8157 Write_Str (", Id=");
8158 Write_Int (Int (Current_Scope));
8159 Write_Str (", Depth=");
8160 Write_Int (Int (Scope_Stack.Last));
8164 -- Deal with copying flags from the previous scope to this one. This is
8165 -- not necessary if either scope is standard, or if the new scope is a
8168 if S /= Standard_Standard
8169 and then Scope (S) /= Standard_Standard
8170 and then not Is_Child_Unit (S)
8172 if Nkind (E) not in N_Entity then
8176 -- Copy categorization flags from Scope (S) to S, this is not done
8177 -- when Scope (S) is Standard_Standard since propagation is from
8178 -- library unit entity inwards. Copy other relevant attributes as
8179 -- well (Discard_Names in particular).
8181 -- We only propagate inwards for library level entities,
8182 -- inner level subprograms do not inherit the categorization.
8184 if Is_Library_Level_Entity (S) then
8185 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8186 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8187 Set_Discard_Names (S, Discard_Names (E));
8188 Set_Suppress_Value_Tracking_On_Call
8189 (S, Suppress_Value_Tracking_On_Call (E));
8190 Set_Categorization_From_Scope (E => S, Scop => E);
8194 if Is_Child_Unit (S)
8195 and then Present (E)
8196 and then Ekind_In (E, E_Package, E_Generic_Package)
8198 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8201 Aux : constant Node_Id :=
8202 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8204 if Present (Default_Storage_Pool (Aux)) then
8205 Default_Pool := Default_Storage_Pool (Aux);
8211 ---------------------
8212 -- Premature_Usage --
8213 ---------------------
8215 procedure Premature_Usage (N : Node_Id) is
8216 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8217 E : Entity_Id := Entity (N);
8220 -- Within an instance, the analysis of the actual for a formal object
8221 -- does not see the name of the object itself. This is significant only
8222 -- if the object is an aggregate, where its analysis does not do any
8223 -- name resolution on component associations. (see 4717-008). In such a
8224 -- case, look for the visible homonym on the chain.
8226 if In_Instance and then Present (Homonym (E)) then
8228 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8234 Set_Etype (N, Etype (E));
8239 if Kind = N_Component_Declaration then
8241 ("component&! cannot be used before end of record declaration", N);
8243 elsif Kind = N_Parameter_Specification then
8245 ("formal parameter&! cannot be used before end of specification",
8248 elsif Kind = N_Discriminant_Specification then
8250 ("discriminant&! cannot be used before end of discriminant part",
8253 elsif Kind = N_Procedure_Specification
8254 or else Kind = N_Function_Specification
8257 ("subprogram&! cannot be used before end of its declaration",
8260 elsif Kind = N_Full_Type_Declaration then
8262 ("type& cannot be used before end of its declaration!", N);
8266 ("object& cannot be used before end of its declaration!", N);
8268 end Premature_Usage;
8270 ------------------------
8271 -- Present_System_Aux --
8272 ------------------------
8274 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8276 Aux_Name : Unit_Name_Type;
8277 Unum : Unit_Number_Type;
8282 function Find_System (C_Unit : Node_Id) return Entity_Id;
8283 -- Scan context clause of compilation unit to find with_clause
8290 function Find_System (C_Unit : Node_Id) return Entity_Id is
8291 With_Clause : Node_Id;
8294 With_Clause := First (Context_Items (C_Unit));
8295 while Present (With_Clause) loop
8296 if (Nkind (With_Clause) = N_With_Clause
8297 and then Chars (Name (With_Clause)) = Name_System)
8298 and then Comes_From_Source (With_Clause)
8309 -- Start of processing for Present_System_Aux
8312 -- The child unit may have been loaded and analyzed already
8314 if Present (System_Aux_Id) then
8317 -- If no previous pragma for System.Aux, nothing to load
8319 elsif No (System_Extend_Unit) then
8322 -- Use the unit name given in the pragma to retrieve the unit.
8323 -- Verify that System itself appears in the context clause of the
8324 -- current compilation. If System is not present, an error will
8325 -- have been reported already.
8328 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8330 The_Unit := Unit (Cunit (Current_Sem_Unit));
8334 (Nkind (The_Unit) = N_Package_Body
8335 or else (Nkind (The_Unit) = N_Subprogram_Body
8336 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8338 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8341 if No (With_Sys) and then Present (N) then
8343 -- If we are compiling a subunit, we need to examine its
8344 -- context as well (Current_Sem_Unit is the parent unit);
8346 The_Unit := Parent (N);
8347 while Nkind (The_Unit) /= N_Compilation_Unit loop
8348 The_Unit := Parent (The_Unit);
8351 if Nkind (Unit (The_Unit)) = N_Subunit then
8352 With_Sys := Find_System (The_Unit);
8356 if No (With_Sys) then
8360 Loc := Sloc (With_Sys);
8361 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8362 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8363 Name_Buffer (1 .. 7) := "system.";
8364 Name_Buffer (Name_Len + 8) := '%';
8365 Name_Buffer (Name_Len + 9) := 's
';
8366 Name_Len := Name_Len + 9;
8367 Aux_Name := Name_Find;
8371 (Load_Name => Aux_Name,
8374 Error_Node => With_Sys);
8376 if Unum /= No_Unit then
8377 Semantics (Cunit (Unum));
8379 Defining_Entity (Specification (Unit (Cunit (Unum))));
8382 Make_With_Clause (Loc,
8384 Make_Expanded_Name (Loc,
8385 Chars => Chars (System_Aux_Id),
8386 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8387 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8389 Set_Entity (Name (Withn), System_Aux_Id);
8391 Set_Library_Unit (Withn, Cunit (Unum));
8392 Set_Corresponding_Spec (Withn, System_Aux_Id);
8393 Set_First_Name (Withn, True);
8394 Set_Implicit_With (Withn, True);
8396 Insert_After (With_Sys, Withn);
8397 Mark_Rewrite_Insertion (Withn);
8398 Set_Context_Installed (Withn);
8402 -- Here if unit load failed
8405 Error_Msg_Name_1 := Name_System;
8406 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8408 ("extension package `%.%` does not exist",
8409 Opt.System_Extend_Unit);
8413 end Present_System_Aux;
8415 -------------------------
8416 -- Restore_Scope_Stack --
8417 -------------------------
8419 procedure Restore_Scope_Stack
8421 Handle_Use : Boolean := True)
8423 SS_Last : constant Int := Scope_Stack.Last;
8427 -- Restore visibility of previous scope stack, if any, using the list
8428 -- we saved (we use Remove, since this list will not be used again).
8431 Elmt := Last_Elmt (List);
8432 exit when Elmt = No_Elmt;
8433 Set_Is_Immediately_Visible (Node (Elmt));
8434 Remove_Last_Elmt (List);
8437 -- Restore use clauses
8439 if SS_Last >= Scope_Stack.First
8440 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8443 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8445 end Restore_Scope_Stack;
8447 ----------------------
8448 -- Save_Scope_Stack --
8449 ----------------------
8451 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8452 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8453 -- from immediate visibility entities and Restore_Scope_Stack took care
8454 -- of restoring their visibility analyzing the context of each entity. The
8455 -- problem of such approach is that it was fragile and caused unexpected
8456 -- visibility problems, and indeed one test was found where there was a
8459 -- Furthermore, the following experiment was carried out:
8461 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8462 -- entities whose attribute Is_Immediately_Visible is modified
8463 -- from True to False.
8465 -- - Restore_Scope_Stack was modified to store in another Elist2
8466 -- all the entities whose attribute Is_Immediately_Visible is
8467 -- modified from False to True.
8469 -- - Extra code was added to verify that all the elements of Elist1
8470 -- are found in Elist2
8472 -- This test shows that there may be more occurrences of this problem which
8473 -- have not yet been detected. As a result, we replaced that approach by
8474 -- the current one in which Save_Scope_Stack returns the list of entities
8475 -- whose visibility is changed, and that list is passed to Restore_Scope_
8476 -- Stack to undo that change. This approach is simpler and safer, although
8477 -- it consumes more memory.
8479 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8480 Result : constant Elist_Id := New_Elmt_List;
8483 SS_Last : constant Int := Scope_Stack.Last;
8485 procedure Remove_From_Visibility (E : Entity_Id);
8486 -- If E is immediately visible then append it to the result and remove
8487 -- it temporarily from visibility.
8489 ----------------------------
8490 -- Remove_From_Visibility --
8491 ----------------------------
8493 procedure Remove_From_Visibility (E : Entity_Id) is
8495 if Is_Immediately_Visible (E) then
8496 Append_Elmt (E, Result);
8497 Set_Is_Immediately_Visible (E, False);
8499 end Remove_From_Visibility;
8501 -- Start of processing for Save_Scope_Stack
8504 if SS_Last >= Scope_Stack.First
8505 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8508 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8511 -- If the call is from within a compilation unit, as when called from
8512 -- Rtsfind, make current entries in scope stack invisible while we
8513 -- analyze the new unit.
8515 for J in reverse 0 .. SS_Last loop
8516 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8517 or else No (Scope_Stack.Table (J).Entity);
8519 S := Scope_Stack.Table (J).Entity;
8521 Remove_From_Visibility (S);
8523 E := First_Entity (S);
8524 while Present (E) loop
8525 Remove_From_Visibility (E);
8533 end Save_Scope_Stack;
8539 procedure Set_Use (L : List_Id) is
8541 Pack_Name : Node_Id;
8548 while Present (Decl) loop
8549 if Nkind (Decl) = N_Use_Package_Clause then
8550 Chain_Use_Clause (Decl);
8552 Pack_Name := First (Names (Decl));
8553 while Present (Pack_Name) loop
8554 Pack := Entity (Pack_Name);
8556 if Ekind (Pack) = E_Package
8557 and then Applicable_Use (Pack_Name)
8559 Use_One_Package (Pack, Decl);
8565 elsif Nkind (Decl) = N_Use_Type_Clause then
8566 Chain_Use_Clause (Decl);
8568 Id := First (Subtype_Marks (Decl));
8569 while Present (Id) loop
8570 if Entity (Id) /= Any_Type then
8583 ---------------------
8584 -- Use_One_Package --
8585 ---------------------
8587 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8590 Current_Instance : Entity_Id := Empty;
8592 Private_With_OK : Boolean := False;
8595 if Ekind (P) /= E_Package then
8600 Set_Current_Use_Clause (P, N);
8602 -- Ada 2005 (AI-50217): Check restriction
8604 if From_Limited_With (P) then
8605 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8608 -- Find enclosing instance, if any
8611 Current_Instance := Current_Scope;
8612 while not Is_Generic_Instance (Current_Instance) loop
8613 Current_Instance := Scope (Current_Instance);
8616 if No (Hidden_By_Use_Clause (N)) then
8617 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8621 -- If unit is a package renaming, indicate that the renamed
8622 -- package is also in use (the flags on both entities must
8623 -- remain consistent, and a subsequent use of either of them
8624 -- should be recognized as redundant).
8626 if Present (Renamed_Object (P)) then
8627 Set_In_Use (Renamed_Object (P));
8628 Set_Current_Use_Clause (Renamed_Object (P), N);
8629 Real_P := Renamed_Object (P);
8634 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8635 -- found in the private part of a package specification
8637 if In_Private_Part (Current_Scope)
8638 and then Has_Private_With (P)
8639 and then Is_Child_Unit (Current_Scope)
8640 and then Is_Child_Unit (P)
8641 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8643 Private_With_OK := True;
8646 -- Loop through entities in one package making them potentially
8649 Id := First_Entity (P);
8651 and then (Id /= First_Private_Entity (P)
8652 or else Private_With_OK) -- Ada 2005 (AI-262)
8654 Prev := Current_Entity (Id);
8655 while Present (Prev) loop
8656 if Is_Immediately_Visible (Prev)
8657 and then (not Is_Overloadable (Prev)
8658 or else not Is_Overloadable (Id)
8659 or else (Type_Conformant (Id, Prev)))
8661 if No (Current_Instance) then
8663 -- Potentially use-visible entity remains hidden
8665 goto Next_Usable_Entity;
8667 -- A use clause within an instance hides outer global entities,
8668 -- which are not used to resolve local entities in the
8669 -- instance. Note that the predefined entities in Standard
8670 -- could not have been hidden in the generic by a use clause,
8671 -- and therefore remain visible. Other compilation units whose
8672 -- entities appear in Standard must be hidden in an instance.
8674 -- To determine whether an entity is external to the instance
8675 -- we compare the scope depth of its scope with that of the
8676 -- current instance. However, a generic actual of a subprogram
8677 -- instance is declared in the wrapper package but will not be
8678 -- hidden by a use-visible entity. similarly, an entity that is
8679 -- declared in an enclosing instance will not be hidden by an
8680 -- an entity declared in a generic actual, which can only have
8681 -- been use-visible in the generic and will not have hidden the
8682 -- entity in the generic parent.
8684 -- If Id is called Standard, the predefined package with the
8685 -- same name is in the homonym chain. It has to be ignored
8686 -- because it has no defined scope (being the only entity in
8687 -- the system with this mandated behavior).
8689 elsif not Is_Hidden (Id)
8690 and then Present (Scope (Prev))
8691 and then not Is_Wrapper_Package (Scope (Prev))
8692 and then Scope_Depth (Scope (Prev)) <
8693 Scope_Depth (Current_Instance)
8694 and then (Scope (Prev) /= Standard_Standard
8695 or else Sloc (Prev) > Standard_Location)
8697 if In_Open_Scopes (Scope (Prev))
8698 and then Is_Generic_Instance (Scope (Prev))
8699 and then Present (Associated_Formal_Package (P))
8704 Set_Is_Potentially_Use_Visible (Id);
8705 Set_Is_Immediately_Visible (Prev, False);
8706 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8710 -- A user-defined operator is not use-visible if the predefined
8711 -- operator for the type is immediately visible, which is the case
8712 -- if the type of the operand is in an open scope. This does not
8713 -- apply to user-defined operators that have operands of different
8714 -- types, because the predefined mixed mode operations (multiply
8715 -- and divide) apply to universal types and do not hide anything.
8717 elsif Ekind (Prev) = E_Operator
8718 and then Operator_Matches_Spec (Prev, Id)
8719 and then In_Open_Scopes
8720 (Scope (Base_Type (Etype (First_Formal (Id)))))
8721 and then (No (Next_Formal (First_Formal (Id)))
8722 or else Etype (First_Formal (Id)) =
8723 Etype (Next_Formal (First_Formal (Id)))
8724 or else Chars (Prev) = Name_Op_Expon)
8726 goto Next_Usable_Entity;
8728 -- In an instance, two homonyms may become use_visible through the
8729 -- actuals of distinct formal packages. In the generic, only the
8730 -- current one would have been visible, so make the other one
8733 elsif Present (Current_Instance)
8734 and then Is_Potentially_Use_Visible (Prev)
8735 and then not Is_Overloadable (Prev)
8736 and then Scope (Id) /= Scope (Prev)
8737 and then Used_As_Generic_Actual (Scope (Prev))
8738 and then Used_As_Generic_Actual (Scope (Id))
8739 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8740 Current_Use_Clause (Scope (Id)))
8742 Set_Is_Potentially_Use_Visible (Prev, False);
8743 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8746 Prev := Homonym (Prev);
8749 -- On exit, we know entity is not hidden, unless it is private
8751 if not Is_Hidden (Id)
8752 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8754 Set_Is_Potentially_Use_Visible (Id);
8756 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8757 Set_Is_Potentially_Use_Visible (Full_View (Id));
8761 <<Next_Usable_Entity>>
8765 -- Child units are also made use-visible by a use clause, but they may
8766 -- appear after all visible declarations in the parent entity list.
8768 while Present (Id) loop
8769 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8770 Set_Is_Potentially_Use_Visible (Id);
8776 if Chars (Real_P) = Name_System
8777 and then Scope (Real_P) = Standard_Standard
8778 and then Present_System_Aux (N)
8780 Use_One_Package (System_Aux_Id, N);
8783 end Use_One_Package;
8789 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8791 Is_Known_Used : Boolean;
8795 function Spec_Reloaded_For_Body return Boolean;
8796 -- Determine whether the compilation unit is a package body and the use
8797 -- type clause is in the spec of the same package. Even though the spec
8798 -- was analyzed first, its context is reloaded when analysing the body.
8800 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8801 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8802 -- class-wide operations of ancestor types are use-visible if the
8803 -- ancestor type is visible.
8805 ----------------------------
8806 -- Spec_Reloaded_For_Body --
8807 ----------------------------
8809 function Spec_Reloaded_For_Body return Boolean is
8811 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8813 Spec : constant Node_Id :=
8814 Parent (List_Containing (Parent (Id)));
8817 -- Check whether type is declared in a package specification,
8818 -- and current unit is the corresponding package body. The
8819 -- use clauses themselves may be within a nested package.
8822 Nkind (Spec) = N_Package_Specification
8824 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8825 Cunit_Entity (Current_Sem_Unit));
8830 end Spec_Reloaded_For_Body;
8832 -------------------------------
8833 -- Use_Class_Wide_Operations --
8834 -------------------------------
8836 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8840 function Is_Class_Wide_Operation_Of
8842 T : Entity_Id) return Boolean;
8843 -- Determine whether a subprogram has a class-wide parameter or
8844 -- result that is T'Class.
8846 ---------------------------------
8847 -- Is_Class_Wide_Operation_Of --
8848 ---------------------------------
8850 function Is_Class_Wide_Operation_Of
8852 T : Entity_Id) return Boolean
8857 Formal := First_Formal (Op);
8858 while Present (Formal) loop
8859 if Etype (Formal) = Class_Wide_Type (T) then
8862 Next_Formal (Formal);
8865 if Etype (Op) = Class_Wide_Type (T) then
8870 end Is_Class_Wide_Operation_Of;
8872 -- Start of processing for Use_Class_Wide_Operations
8875 Scop := Scope (Typ);
8876 if not Is_Hidden (Scop) then
8877 Ent := First_Entity (Scop);
8878 while Present (Ent) loop
8879 if Is_Overloadable (Ent)
8880 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8881 and then not Is_Potentially_Use_Visible (Ent)
8883 Set_Is_Potentially_Use_Visible (Ent);
8884 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8891 if Is_Derived_Type (Typ) then
8892 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8894 end Use_Class_Wide_Operations;
8896 -- Start of processing for Use_One_Type
8899 -- It is the type determined by the subtype mark (8.4(8)) whose
8900 -- operations become potentially use-visible.
8902 T := Base_Type (Entity (Id));
8904 -- Either the type itself is used, the package where it is declared
8905 -- is in use or the entity is declared in the current package, thus
8910 or else In_Use (Scope (T))
8911 or else Scope (T) = Current_Scope;
8913 Set_Redundant_Use (Id,
8914 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8916 if Ekind (T) = E_Incomplete_Type then
8917 Error_Msg_N ("premature usage of incomplete type", Id);
8919 elsif In_Open_Scopes (Scope (T)) then
8922 -- A limited view cannot appear in a use_type clause. However, an access
8923 -- type whose designated type is limited has the flag but is not itself
8924 -- a limited view unless we only have a limited view of its enclosing
8927 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8929 ("incomplete type from limited view "
8930 & "cannot appear in use clause", Id);
8932 -- If the subtype mark designates a subtype in a different package,
8933 -- we have to check that the parent type is visible, otherwise the
8934 -- use type clause is a noop. Not clear how to do that???
8936 elsif not Redundant_Use (Id) then
8939 -- If T is tagged, primitive operators on class-wide operands
8940 -- are also available.
8942 if Is_Tagged_Type (T) then
8943 Set_In_Use (Class_Wide_Type (T));
8946 Set_Current_Use_Clause (T, Parent (Id));
8948 -- Iterate over primitive operations of the type. If an operation is
8949 -- already use_visible, it is the result of a previous use_clause,
8950 -- and already appears on the corresponding entity chain. If the
8951 -- clause is being reinstalled, operations are already use-visible.
8957 Op_List := Collect_Primitive_Operations (T);
8958 Elmt := First_Elmt (Op_List);
8959 while Present (Elmt) loop
8960 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
8961 or else Chars (Node (Elmt)) in Any_Operator_Name)
8962 and then not Is_Hidden (Node (Elmt))
8963 and then not Is_Potentially_Use_Visible (Node (Elmt))
8965 Set_Is_Potentially_Use_Visible (Node (Elmt));
8966 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8968 elsif Ada_Version >= Ada_2012
8969 and then All_Present (Parent (Id))
8970 and then not Is_Hidden (Node (Elmt))
8971 and then not Is_Potentially_Use_Visible (Node (Elmt))
8973 Set_Is_Potentially_Use_Visible (Node (Elmt));
8974 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8981 if Ada_Version >= Ada_2012
8982 and then All_Present (Parent (Id))
8983 and then Is_Tagged_Type (T)
8985 Use_Class_Wide_Operations (T);
8989 -- If warning on redundant constructs, check for unnecessary WITH
8991 if Warn_On_Redundant_Constructs
8992 and then Is_Known_Used
8994 -- with P; with P; use P;
8995 -- package P is package X is package body X is
8996 -- type T ... use P.T;
8998 -- The compilation unit is the body of X. GNAT first compiles the
8999 -- spec of X, then proceeds to the body. At that point P is marked
9000 -- as use visible. The analysis then reinstalls the spec along with
9001 -- its context. The use clause P.T is now recognized as redundant,
9002 -- but in the wrong context. Do not emit a warning in such cases.
9003 -- Do not emit a warning either if we are in an instance, there is
9004 -- no redundancy between an outer use_clause and one that appears
9005 -- within the generic.
9007 and then not Spec_Reloaded_For_Body
9008 and then not In_Instance
9010 -- The type already has a use clause
9014 -- Case where we know the current use clause for the type
9016 if Present (Current_Use_Clause (T)) then
9017 Use_Clause_Known : declare
9018 Clause1 : constant Node_Id := Parent (Id);
9019 Clause2 : constant Node_Id := Current_Use_Clause (T);
9026 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9027 -- Return the appropriate entity for determining which unit
9028 -- has a deeper scope: the defining entity for U, unless U
9029 -- is a package instance, in which case we retrieve the
9030 -- entity of the instance spec.
9032 --------------------
9033 -- Entity_Of_Unit --
9034 --------------------
9036 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9038 if Nkind (U) = N_Package_Instantiation
9039 and then Analyzed (U)
9041 return Defining_Entity (Instance_Spec (U));
9043 return Defining_Entity (U);
9047 -- Start of processing for Use_Clause_Known
9050 -- If both current use type clause and the use type clause
9051 -- for the type are at the compilation unit level, one of
9052 -- the units must be an ancestor of the other, and the
9053 -- warning belongs on the descendant.
9055 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9057 Nkind (Parent (Clause2)) = N_Compilation_Unit
9059 -- If the unit is a subprogram body that acts as spec,
9060 -- the context clause is shared with the constructed
9061 -- subprogram spec. Clearly there is no redundancy.
9063 if Clause1 = Clause2 then
9067 Unit1 := Unit (Parent (Clause1));
9068 Unit2 := Unit (Parent (Clause2));
9070 -- If both clauses are on same unit, or one is the body
9071 -- of the other, or one of them is in a subunit, report
9072 -- redundancy on the later one.
9074 if Unit1 = Unit2 then
9075 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9076 Error_Msg_NE -- CODEFIX
9077 ("& is already use-visible through previous "
9078 & "use_type_clause #??", Clause1, T);
9081 elsif Nkind (Unit1) = N_Subunit then
9082 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9083 Error_Msg_NE -- CODEFIX
9084 ("& is already use-visible through previous "
9085 & "use_type_clause #??", Clause1, T);
9088 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9089 and then Nkind (Unit1) /= Nkind (Unit2)
9090 and then Nkind (Unit1) /= N_Subunit
9092 Error_Msg_Sloc := Sloc (Clause1);
9093 Error_Msg_NE -- CODEFIX
9094 ("& is already use-visible through previous "
9095 & "use_type_clause #??", Current_Use_Clause (T), T);
9099 -- There is a redundant use type clause in a child unit.
9100 -- Determine which of the units is more deeply nested.
9101 -- If a unit is a package instance, retrieve the entity
9102 -- and its scope from the instance spec.
9104 Ent1 := Entity_Of_Unit (Unit1);
9105 Ent2 := Entity_Of_Unit (Unit2);
9107 if Scope (Ent2) = Standard_Standard then
9108 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9111 elsif Scope (Ent1) = Standard_Standard then
9112 Error_Msg_Sloc := Sloc (Id);
9115 -- If both units are child units, we determine which one
9116 -- is the descendant by the scope distance to the
9117 -- ultimate parent unit.
9127 and then Present (S2)
9128 and then S1 /= Standard_Standard
9129 and then S2 /= Standard_Standard
9135 if S1 = Standard_Standard then
9136 Error_Msg_Sloc := Sloc (Id);
9139 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9145 Error_Msg_NE -- CODEFIX
9146 ("& is already use-visible through previous "
9147 & "use_type_clause #??", Err_No, Id);
9149 -- Case where current use type clause and the use type
9150 -- clause for the type are not both at the compilation unit
9151 -- level. In this case we don't have location information.
9154 Error_Msg_NE -- CODEFIX
9155 ("& is already use-visible through previous "
9156 & "use type clause??", Id, T);
9158 end Use_Clause_Known;
9160 -- Here if Current_Use_Clause is not set for T, another case
9161 -- where we do not have the location information available.
9164 Error_Msg_NE -- CODEFIX
9165 ("& is already use-visible through previous "
9166 & "use type clause??", Id, T);
9169 -- The package where T is declared is already used
9171 elsif In_Use (Scope (T)) then
9172 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9173 Error_Msg_NE -- CODEFIX
9174 ("& is already use-visible through package use clause #??",
9177 -- The current scope is the package where T is declared
9180 Error_Msg_Node_2 := Scope (T);
9181 Error_Msg_NE -- CODEFIX
9182 ("& is already use-visible inside package &??", Id, T);
9191 procedure Write_Info is
9192 Id : Entity_Id := First_Entity (Current_Scope);
9195 -- No point in dumping standard entities
9197 if Current_Scope = Standard_Standard then
9201 Write_Str ("========================================================");
9203 Write_Str (" Defined Entities in ");
9204 Write_Name (Chars (Current_Scope));
9206 Write_Str ("========================================================");
9210 Write_Str ("-- none --");
9214 while Present (Id) loop
9215 Write_Entity_Info (Id, " ");
9220 if Scope (Current_Scope) = Standard_Standard then
9222 -- Print information on the current unit itself
9224 Write_Entity_Info (Current_Scope, " ");
9237 for J in reverse 1 .. Scope_Stack.Last loop
9238 S := Scope_Stack.Table (J).Entity;
9239 Write_Int (Int (S));
9240 Write_Str (" === ");
9241 Write_Name (Chars (S));
9250 procedure we (S : Entity_Id) is
9253 E := First_Entity (S);
9254 while Present (E) loop
9255 Write_Int (Int (E));
9256 Write_Str (" === ");
9257 Write_Name (Chars (E));