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_Tss
; use Exp_Tss
;
32 with Exp_Util
; use Exp_Util
;
33 with Fname
; use Fname
;
34 with Freeze
; use Freeze
;
35 with Ghost
; use Ghost
;
36 with Impunit
; use Impunit
;
38 with Lib
.Load
; use Lib
.Load
;
39 with Lib
.Xref
; use Lib
.Xref
;
40 with Namet
; use Namet
;
41 with Namet
.Sp
; use Namet
.Sp
;
42 with Nlists
; use Nlists
;
43 with Nmake
; use Nmake
;
45 with Output
; use Output
;
46 with Restrict
; use Restrict
;
47 with Rident
; use Rident
;
48 with Rtsfind
; use Rtsfind
;
50 with Sem_Aux
; use Sem_Aux
;
51 with Sem_Cat
; use Sem_Cat
;
52 with Sem_Ch3
; use Sem_Ch3
;
53 with Sem_Ch4
; use Sem_Ch4
;
54 with Sem_Ch6
; use Sem_Ch6
;
55 with Sem_Ch12
; use Sem_Ch12
;
56 with Sem_Ch13
; use Sem_Ch13
;
57 with Sem_Dim
; use Sem_Dim
;
58 with Sem_Disp
; use Sem_Disp
;
59 with Sem_Dist
; use Sem_Dist
;
60 with Sem_Eval
; use Sem_Eval
;
61 with Sem_Res
; use Sem_Res
;
62 with Sem_Util
; use Sem_Util
;
63 with Sem_Type
; use Sem_Type
;
64 with Stand
; use Stand
;
65 with Sinfo
; use Sinfo
;
66 with Sinfo
.CN
; use Sinfo
.CN
;
67 with Snames
; use Snames
;
68 with Style
; use Style
;
70 with Targparm
; use Targparm
;
71 with Tbuild
; use Tbuild
;
72 with Uintp
; use Uintp
;
74 package body Sem_Ch8
is
76 ------------------------------------
77 -- Visibility and Name Resolution --
78 ------------------------------------
80 -- This package handles name resolution and the collection of possible
81 -- interpretations for overloaded names, prior to overload resolution.
83 -- Name resolution is the process that establishes a mapping between source
84 -- identifiers and the entities they denote at each point in the program.
85 -- Each entity is represented by a defining occurrence. Each identifier
86 -- that denotes an entity points to the corresponding defining occurrence.
87 -- This is the entity of the applied occurrence. Each occurrence holds
88 -- an index into the names table, where source identifiers are stored.
90 -- Each entry in the names table for an identifier or designator uses the
91 -- Info pointer to hold a link to the currently visible entity that has
92 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
93 -- in package Sem_Util). The visibility is initialized at the beginning of
94 -- semantic processing to make entities in package Standard immediately
95 -- visible. The visibility table is used in a more subtle way when
96 -- compiling subunits (see below).
98 -- Entities that have the same name (i.e. homonyms) are chained. In the
99 -- case of overloaded entities, this chain holds all the possible meanings
100 -- of a given identifier. The process of overload resolution uses type
101 -- information to select from this chain the unique meaning of a given
104 -- Entities are also chained in their scope, through the Next_Entity link.
105 -- As a consequence, the name space is organized as a sparse matrix, where
106 -- each row corresponds to a scope, and each column to a source identifier.
107 -- Open scopes, that is to say scopes currently being compiled, have their
108 -- corresponding rows of entities in order, innermost scope first.
110 -- The scopes of packages that are mentioned in context clauses appear in
111 -- no particular order, interspersed among open scopes. This is because
112 -- in the course of analyzing the context of a compilation, a package
113 -- declaration is first an open scope, and subsequently an element of the
114 -- context. If subunits or child units are present, a parent unit may
115 -- appear under various guises at various times in the compilation.
117 -- When the compilation of the innermost scope is complete, the entities
118 -- defined therein are no longer visible. If the scope is not a package
119 -- declaration, these entities are never visible subsequently, and can be
120 -- removed from visibility chains. If the scope is a package declaration,
121 -- its visible declarations may still be accessible. Therefore the entities
122 -- defined in such a scope are left on the visibility chains, and only
123 -- their visibility (immediately visibility or potential use-visibility)
126 -- The ordering of homonyms on their chain does not necessarily follow
127 -- the order of their corresponding scopes on the scope stack. For
128 -- example, if package P and the enclosing scope both contain entities
129 -- named E, then when compiling the package body the chain for E will
130 -- hold the global entity first, and the local one (corresponding to
131 -- the current inner scope) next. As a result, name resolution routines
132 -- do not assume any relative ordering of the homonym chains, either
133 -- for scope nesting or to order of appearance of context clauses.
135 -- When compiling a child unit, entities in the parent scope are always
136 -- immediately visible. When compiling the body of a child unit, private
137 -- entities in the parent must also be made immediately visible. There
138 -- are separate routines to make the visible and private declarations
139 -- visible at various times (see package Sem_Ch7).
141 -- +--------+ +-----+
142 -- | In use |-------->| EU1 |-------------------------->
143 -- +--------+ +-----+
145 -- +--------+ +-----+ +-----+
146 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
147 -- +--------+ +-----+ +-----+
149 -- +---------+ | +-----+
150 -- | with'ed |------------------------------>| EW2 |--->
151 -- +---------+ | +-----+
153 -- +--------+ +-----+ +-----+
154 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
155 -- +--------+ +-----+ +-----+
157 -- +--------+ +-----+ +-----+
158 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
159 -- +--------+ +-----+ +-----+
163 -- | | with'ed |----------------------------------------->
167 -- (innermost first) | |
168 -- +----------------------------+
169 -- Names table => | Id1 | | | | Id2 |
170 -- +----------------------------+
172 -- Name resolution must deal with several syntactic forms: simple names,
173 -- qualified names, indexed names, and various forms of calls.
175 -- Each identifier points to an entry in the names table. The resolution
176 -- of a simple name consists in traversing the homonym chain, starting
177 -- from the names table. If an entry is immediately visible, it is the one
178 -- designated by the identifier. If only potentially use-visible entities
179 -- are on the chain, we must verify that they do not hide each other. If
180 -- the entity we find is overloadable, we collect all other overloadable
181 -- entities on the chain as long as they are not hidden.
183 -- To resolve expanded names, we must find the entity at the intersection
184 -- of the entity chain for the scope (the prefix) and the homonym chain
185 -- for the selector. In general, homonym chains will be much shorter than
186 -- entity chains, so it is preferable to start from the names table as
187 -- well. If the entity found is overloadable, we must collect all other
188 -- interpretations that are defined in the scope denoted by the prefix.
190 -- For records, protected types, and tasks, their local entities are
191 -- removed from visibility chains on exit from the corresponding scope.
192 -- From the outside, these entities are always accessed by selected
193 -- notation, and the entity chain for the record type, protected type,
194 -- etc. is traversed sequentially in order to find the designated entity.
196 -- The discriminants of a type and the operations of a protected type or
197 -- task are unchained on exit from the first view of the type, (such as
198 -- a private or incomplete type declaration, or a protected type speci-
199 -- fication) and re-chained when compiling the second view.
201 -- In the case of operators, we do not make operators on derived types
202 -- explicit. As a result, the notation P."+" may denote either a user-
203 -- defined function with name "+", or else an implicit declaration of the
204 -- operator "+" in package P. The resolution of expanded names always
205 -- tries to resolve an operator name as such an implicitly defined entity,
206 -- in addition to looking for explicit declarations.
208 -- All forms of names that denote entities (simple names, expanded names,
209 -- character literals in some cases) have a Entity attribute, which
210 -- identifies the entity denoted by the name.
212 ---------------------
213 -- The Scope Stack --
214 ---------------------
216 -- The Scope stack keeps track of the scopes currently been compiled.
217 -- Every entity that contains declarations (including records) is placed
218 -- on the scope stack while it is being processed, and removed at the end.
219 -- Whenever a non-package scope is exited, the entities defined therein
220 -- are removed from the visibility table, so that entities in outer scopes
221 -- become visible (see previous description). On entry to Sem, the scope
222 -- stack only contains the package Standard. As usual, subunits complicate
223 -- this picture ever so slightly.
225 -- The Rtsfind mechanism can force a call to Semantics while another
226 -- compilation is in progress. The unit retrieved by Rtsfind must be
227 -- compiled in its own context, and has no access to the visibility of
228 -- the unit currently being compiled. The procedures Save_Scope_Stack and
229 -- Restore_Scope_Stack make entities in current open scopes invisible
230 -- before compiling the retrieved unit, and restore the compilation
231 -- environment afterwards.
233 ------------------------
234 -- Compiling subunits --
235 ------------------------
237 -- Subunits must be compiled in the environment of the corresponding stub,
238 -- that is to say with the same visibility into the parent (and its
239 -- context) that is available at the point of the stub declaration, but
240 -- with the additional visibility provided by the context clause of the
241 -- subunit itself. As a result, compilation of a subunit forces compilation
242 -- of the parent (see description in lib-). At the point of the stub
243 -- declaration, Analyze is called recursively to compile the proper body of
244 -- the subunit, but without reinitializing the names table, nor the scope
245 -- stack (i.e. standard is not pushed on the stack). In this fashion the
246 -- context of the subunit is added to the context of the parent, and the
247 -- subunit is compiled in the correct environment. Note that in the course
248 -- of processing the context of a subunit, Standard will appear twice on
249 -- the scope stack: once for the parent of the subunit, and once for the
250 -- unit in the context clause being compiled. However, the two sets of
251 -- entities are not linked by homonym chains, so that the compilation of
252 -- any context unit happens in a fresh visibility environment.
254 -------------------------------
255 -- Processing of USE Clauses --
256 -------------------------------
258 -- Every defining occurrence has a flag indicating if it is potentially use
259 -- visible. Resolution of simple names examines this flag. The processing
260 -- of use clauses consists in setting this flag on all visible entities
261 -- defined in the corresponding package. On exit from the scope of the use
262 -- clause, the corresponding flag must be reset. However, a package may
263 -- appear in several nested use clauses (pathological but legal, alas)
264 -- which forces us to use a slightly more involved scheme:
266 -- a) The defining occurrence for a package holds a flag -In_Use- to
267 -- indicate that it is currently in the scope of a use clause. If a
268 -- redundant use clause is encountered, then the corresponding occurrence
269 -- of the package name is flagged -Redundant_Use-.
271 -- b) On exit from a scope, the use clauses in its declarative part are
272 -- scanned. The visibility flag is reset in all entities declared in
273 -- package named in a use clause, as long as the package is not flagged
274 -- as being in a redundant use clause (in which case the outer use
275 -- clause is still in effect, and the direct visibility of its entities
276 -- must be retained).
278 -- Note that entities are not removed from their homonym chains on exit
279 -- from the package specification. A subsequent use clause does not need
280 -- to rechain the visible entities, but only to establish their direct
283 -----------------------------------
284 -- Handling private declarations --
285 -----------------------------------
287 -- The principle that each entity has a single defining occurrence clashes
288 -- with the presence of two separate definitions for private types: the
289 -- first is the private type declaration, and second is the full type
290 -- declaration. It is important that all references to the type point to
291 -- the same defining occurrence, namely the first one. To enforce the two
292 -- separate views of the entity, the corresponding information is swapped
293 -- between the two declarations. Outside of the package, the defining
294 -- occurrence only contains the private declaration information, while in
295 -- the private part and the body of the package the defining occurrence
296 -- contains the full declaration. To simplify the swap, the defining
297 -- occurrence that currently holds the private declaration points to the
298 -- full declaration. During semantic processing the defining occurrence
299 -- also points to a list of private dependents, that is to say access types
300 -- or composite types whose designated types or component types are
301 -- subtypes or derived types of the private type in question. After the
302 -- full declaration has been seen, the private dependents are updated to
303 -- indicate that they have full definitions.
305 ------------------------------------
306 -- Handling of Undefined Messages --
307 ------------------------------------
309 -- In normal mode, only the first use of an undefined identifier generates
310 -- a message. The table Urefs is used to record error messages that have
311 -- been issued so that second and subsequent ones do not generate further
312 -- messages. However, the second reference causes text to be added to the
313 -- original undefined message noting "(more references follow)". The
314 -- full error list option (-gnatf) forces messages to be generated for
315 -- every reference and disconnects the use of this table.
317 type Uref_Entry
is record
319 -- Node for identifier for which original message was posted. The
320 -- Chars field of this identifier is used to detect later references
321 -- to the same identifier.
324 -- Records error message Id of original undefined message. Reset to
325 -- No_Error_Msg after the second occurrence, where it is used to add
326 -- text to the original message as described above.
329 -- Set if the message is not visible rather than undefined
332 -- Records location of error message. Used to make sure that we do
333 -- not consider a, b : undefined as two separate instances, which
334 -- would otherwise happen, since the parser converts this sequence
335 -- to a : undefined; b : undefined.
339 package Urefs
is new Table
.Table
(
340 Table_Component_Type
=> Uref_Entry
,
341 Table_Index_Type
=> Nat
,
342 Table_Low_Bound
=> 1,
344 Table_Increment
=> 100,
345 Table_Name
=> "Urefs");
347 Candidate_Renaming
: Entity_Id
;
348 -- Holds a candidate interpretation that appears in a subprogram renaming
349 -- declaration and does not match the given specification, but matches at
350 -- least on the first formal. Allows better error message when given
351 -- specification omits defaulted parameters, a common error.
353 -----------------------
354 -- Local Subprograms --
355 -----------------------
357 procedure Analyze_Generic_Renaming
360 -- Common processing for all three kinds of generic renaming declarations.
361 -- Enter new name and indicate that it renames the generic unit.
363 procedure Analyze_Renamed_Character
367 -- Renamed entity is given by a character literal, which must belong
368 -- to the return type of the new entity. Is_Body indicates whether the
369 -- declaration is a renaming_as_body. If the original declaration has
370 -- already been frozen (because of an intervening body, e.g.) the body of
371 -- the function must be built now. The same applies to the following
372 -- various renaming procedures.
374 procedure Analyze_Renamed_Dereference
378 -- Renamed entity is given by an explicit dereference. Prefix must be a
379 -- conformant access_to_subprogram type.
381 procedure Analyze_Renamed_Entry
385 -- If the renamed entity in a subprogram renaming is an entry or protected
386 -- subprogram, build a body for the new entity whose only statement is a
387 -- call to the renamed entity.
389 procedure Analyze_Renamed_Family_Member
393 -- Used when the renamed entity is an indexed component. The prefix must
394 -- denote an entry family.
396 procedure Analyze_Renamed_Primitive_Operation
400 -- If the renamed entity in a subprogram renaming is a primitive operation
401 -- or a class-wide operation in prefix form, save the target object,
402 -- which must be added to the list of actuals in any subsequent call.
403 -- The renaming operation is intrinsic because the compiler must in
404 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
406 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
407 -- Common code to Use_One_Package and Set_Use, to determine whether use
408 -- clause must be processed. Pack_Name is an entity name that references
409 -- the package in question.
411 procedure Attribute_Renaming
(N
: Node_Id
);
412 -- Analyze renaming of attribute as subprogram. The renaming declaration N
413 -- is rewritten as a subprogram body that returns the attribute reference
414 -- applied to the formals of the function.
416 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
417 -- Set Entity, with style check if need be. For a discriminant reference,
418 -- replace by the corresponding discriminal, i.e. the parameter of the
419 -- initialization procedure that corresponds to the discriminant.
421 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
422 -- A renaming_as_body may occur after the entity of the original decla-
423 -- ration has been frozen. In that case, the body of the new entity must
424 -- be built now, because the usual mechanism of building the renamed
425 -- body at the point of freezing will not work. Subp is the subprogram
426 -- for which N provides the Renaming_As_Body.
428 procedure Check_In_Previous_With_Clause
431 -- N is a use_package clause and Nam the package name, or N is a use_type
432 -- clause and Nam is the prefix of the type name. In either case, verify
433 -- that the package is visible at that point in the context: either it
434 -- appears in a previous with_clause, or because it is a fully qualified
435 -- name and the root ancestor appears in a previous with_clause.
437 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
438 -- Verify that the entity in a renaming declaration that is a library unit
439 -- is itself a library unit and not a nested unit or subunit. Also check
440 -- that if the renaming is a child unit of a generic parent, then the
441 -- renamed unit must also be a child unit of that parent. Finally, verify
442 -- that a renamed generic unit is not an implicit child declared within
443 -- an instance of the parent.
445 procedure Chain_Use_Clause
(N
: Node_Id
);
446 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
447 -- the proper scope table entry. This is usually the current scope, but it
448 -- will be an inner scope when installing the use clauses of the private
449 -- declarations of a parent unit prior to compiling the private part of a
450 -- child unit. This chain is traversed when installing/removing use clauses
451 -- when compiling a subunit or instantiating a generic body on the fly,
452 -- when it is necessary to save and restore full environments.
454 function Enclosing_Instance
return Entity_Id
;
455 -- In an instance nested within another one, several semantic checks are
456 -- unnecessary because the legality of the nested instance has been checked
457 -- in the enclosing generic unit. This applies in particular to legality
458 -- checks on actuals for formal subprograms of the inner instance, which
459 -- are checked as subprogram renamings, and may be complicated by confusion
460 -- in private/full views. This function returns the instance enclosing the
461 -- current one if there is such, else it returns Empty.
463 -- If the renaming determines the entity for the default of a formal
464 -- subprogram nested within another instance, choose the innermost
465 -- candidate. This is because if the formal has a box, and we are within
466 -- an enclosing instance where some candidate interpretations are local
467 -- to this enclosing instance, we know that the default was properly
468 -- resolved when analyzing the generic, so we prefer the local
469 -- candidates to those that are external. This is not always the case
470 -- but is a reasonable heuristic on the use of nested generics. The
471 -- proper solution requires a full renaming model.
473 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
474 -- Find a type derived from Character or Wide_Character in the prefix of N.
475 -- Used to resolved qualified names whose selector is a character literal.
477 function Has_Private_With
(E
: Entity_Id
) return Boolean;
478 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
479 -- private with on E.
481 procedure Find_Expanded_Name
(N
: Node_Id
);
482 -- The input is a selected component known to be an expanded name. Verify
483 -- legality of selector given the scope denoted by prefix, and change node
484 -- N into a expanded name with a properly set Entity field.
486 function Find_Renamed_Entity
490 Is_Actual
: Boolean := False) return Entity_Id
;
491 -- Find the renamed entity that corresponds to the given parameter profile
492 -- in a subprogram renaming declaration. The renamed entity may be an
493 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
494 -- indicates that the renaming is the one generated for an actual subpro-
495 -- gram in an instance, for which special visibility checks apply.
497 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
498 -- N is an expanded name whose selector is an operator name (e.g. P."+").
499 -- declarative part contains an implicit declaration of an operator if it
500 -- has a declaration of a type to which one of the predefined operators
501 -- apply. The existence of this routine is an implementation artifact. A
502 -- more straightforward but more space-consuming choice would be to make
503 -- all inherited operators explicit in the symbol table.
505 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
506 -- A subprogram defined by a renaming declaration inherits the parameter
507 -- profile of the renamed entity. The subtypes given in the subprogram
508 -- specification are discarded and replaced with those of the renamed
509 -- subprogram, which are then used to recheck the default values.
511 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
512 -- Prefix is appropriate for record if it is of a record type, or an access
515 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
516 -- True if it is of a task type, a protected type, or else an access to one
519 procedure Note_Redundant_Use
(Clause
: Node_Id
);
520 -- Mark the name in a use clause as redundant if the corresponding entity
521 -- is already use-visible. Emit a warning if the use clause comes from
522 -- source and the proper warnings are enabled.
524 procedure Premature_Usage
(N
: Node_Id
);
525 -- Diagnose usage of an entity before it is visible
527 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
528 -- Make visible entities declared in package P potentially use-visible
529 -- in the current context. Also used in the analysis of subunits, when
530 -- re-installing use clauses of parent units. N is the use_clause that
531 -- names P (and possibly other packages).
533 procedure Use_One_Type
(Id
: Node_Id
; Installed
: Boolean := False);
534 -- Id is the subtype mark from a use type clause. This procedure makes
535 -- the primitive operators of the type potentially use-visible. The
536 -- boolean flag Installed indicates that the clause is being reinstalled
537 -- after previous analysis, and primitive operations are already chained
538 -- on the Used_Operations list of the clause.
540 procedure Write_Info
;
541 -- Write debugging information on entities declared in current scope
543 --------------------------------
544 -- Analyze_Exception_Renaming --
545 --------------------------------
547 -- The language only allows a single identifier, but the tree holds an
548 -- identifier list. The parser has already issued an error message if
549 -- there is more than one element in the list.
551 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
552 Id
: constant Node_Id
:= Defining_Identifier
(N
);
553 Nam
: constant Node_Id
:= Name
(N
);
556 -- The exception renaming declaration may be subject to pragma Ghost
557 -- with policy Ignore. Set the mode now to ensure that any nodes
558 -- generated during analysis and expansion are properly flagged as
562 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
567 Set_Ekind
(Id
, E_Exception
);
568 Set_Etype
(Id
, Standard_Exception_Type
);
569 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
571 if not Is_Entity_Name
(Nam
)
572 or else Ekind
(Entity
(Nam
)) /= E_Exception
574 Error_Msg_N
("invalid exception name in renaming", Nam
);
576 if Present
(Renamed_Object
(Entity
(Nam
))) then
577 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
579 Set_Renamed_Object
(Id
, Entity
(Nam
));
582 -- An exception renaming is Ghost if the renamed entity is Ghost or
583 -- the construct appears within a Ghost scope.
585 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
586 Set_Is_Ghost_Entity
(Id
);
590 -- Implementation-defined aspect specifications can appear in a renaming
591 -- declaration, but not language-defined ones. The call to procedure
592 -- Analyze_Aspect_Specifications will take care of this error check.
594 if Has_Aspects
(N
) then
595 Analyze_Aspect_Specifications
(N
, Id
);
597 end Analyze_Exception_Renaming
;
599 ---------------------------
600 -- Analyze_Expanded_Name --
601 ---------------------------
603 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
605 -- If the entity pointer is already set, this is an internal node, or a
606 -- node that is analyzed more than once, after a tree modification. In
607 -- such a case there is no resolution to perform, just set the type. For
608 -- completeness, analyze prefix as well.
610 if Present
(Entity
(N
)) then
611 if Is_Type
(Entity
(N
)) then
612 Set_Etype
(N
, Entity
(N
));
614 Set_Etype
(N
, Etype
(Entity
(N
)));
617 Analyze
(Prefix
(N
));
620 Find_Expanded_Name
(N
);
623 Analyze_Dimension
(N
);
624 end Analyze_Expanded_Name
;
626 ---------------------------------------
627 -- Analyze_Generic_Function_Renaming --
628 ---------------------------------------
630 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
632 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
633 end Analyze_Generic_Function_Renaming
;
635 --------------------------------------
636 -- Analyze_Generic_Package_Renaming --
637 --------------------------------------
639 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
641 -- Test for the Text_IO special unit case here, since we may be renaming
642 -- one of the subpackages of Text_IO, then join common routine.
644 Check_Text_IO_Special_Unit
(Name
(N
));
646 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
647 end Analyze_Generic_Package_Renaming
;
649 ----------------------------------------
650 -- Analyze_Generic_Procedure_Renaming --
651 ----------------------------------------
653 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
655 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
656 end Analyze_Generic_Procedure_Renaming
;
658 ------------------------------
659 -- Analyze_Generic_Renaming --
660 ------------------------------
662 procedure Analyze_Generic_Renaming
666 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
668 Inst
: Boolean := False; -- prevent junk warning
671 if Name
(N
) = Error
then
675 -- The generic renaming declaration may be subject to pragma Ghost with
676 -- policy Ignore. Set the mode now to ensure that any nodes generated
677 -- during analysis and expansion are properly flagged as ignored Ghost.
680 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
682 Generate_Definition
(New_P
);
684 if Current_Scope
/= Standard_Standard
then
685 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
688 if Nkind
(Name
(N
)) = N_Selected_Component
then
689 Check_Generic_Child_Unit
(Name
(N
), Inst
);
694 if not Is_Entity_Name
(Name
(N
)) then
695 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
698 Old_P
:= Entity
(Name
(N
));
702 Set_Ekind
(New_P
, K
);
704 if Etype
(Old_P
) = Any_Type
then
707 elsif Ekind
(Old_P
) /= K
then
708 Error_Msg_N
("invalid generic unit name", Name
(N
));
711 if Present
(Renamed_Object
(Old_P
)) then
712 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
714 Set_Renamed_Object
(New_P
, Old_P
);
717 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
718 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
720 Set_Etype
(New_P
, Etype
(Old_P
));
721 Set_Has_Completion
(New_P
);
723 -- An generic renaming is Ghost if the renamed entity is Ghost or the
724 -- construct appears within a Ghost scope.
726 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
727 Set_Is_Ghost_Entity
(New_P
);
730 if In_Open_Scopes
(Old_P
) then
731 Error_Msg_N
("within its scope, generic denotes its instance", N
);
734 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
735 -- renamings and subsequent instantiations of Unchecked_Conversion.
737 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
738 Set_Is_Intrinsic_Subprogram
739 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
742 Check_Library_Unit_Renaming
(N
, Old_P
);
745 -- Implementation-defined aspect specifications can appear in a renaming
746 -- declaration, but not language-defined ones. The call to procedure
747 -- Analyze_Aspect_Specifications will take care of this error check.
749 if Has_Aspects
(N
) then
750 Analyze_Aspect_Specifications
(N
, New_P
);
752 end Analyze_Generic_Renaming
;
754 -----------------------------
755 -- Analyze_Object_Renaming --
756 -----------------------------
758 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
759 Loc
: constant Source_Ptr
:= Sloc
(N
);
760 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
762 Nam
: constant Node_Id
:= Name
(N
);
766 procedure Check_Constrained_Object
;
767 -- If the nominal type is unconstrained but the renamed object is
768 -- constrained, as can happen with renaming an explicit dereference or
769 -- a function return, build a constrained subtype from the object. If
770 -- the renaming is for a formal in an accept statement, the analysis
771 -- has already established its actual subtype. This is only relevant
772 -- if the renamed object is an explicit dereference.
774 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
775 -- Determine whether entity E is inside a generic cope
777 ------------------------------
778 -- Check_Constrained_Object --
779 ------------------------------
781 procedure Check_Constrained_Object
is
782 Typ
: constant Entity_Id
:= Etype
(Nam
);
786 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
787 and then Is_Composite_Type
(Etype
(Nam
))
788 and then not Is_Constrained
(Etype
(Nam
))
789 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
790 and then Expander_Active
792 -- If Actual_Subtype is already set, nothing to do
794 if Ekind_In
(Id
, E_Variable
, E_Constant
)
795 and then Present
(Actual_Subtype
(Id
))
799 -- A renaming of an unchecked union has no actual subtype
801 elsif Is_Unchecked_Union
(Typ
) then
804 -- If a record is limited its size is invariant. This is the case
805 -- in particular with record types with an access discirminant
806 -- that are used in iterators. This is an optimization, but it
807 -- also prevents typing anomalies when the prefix is further
808 -- expanded. Limited types with discriminants are included.
810 elsif Is_Limited_Record
(Typ
)
812 (Ekind
(Typ
) = E_Limited_Private_Type
813 and then Has_Discriminants
(Typ
)
814 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
819 Subt
:= Make_Temporary
(Loc
, 'T');
820 Remove_Side_Effects
(Nam
);
822 Make_Subtype_Declaration
(Loc
,
823 Defining_Identifier
=> Subt
,
824 Subtype_Indication
=>
825 Make_Subtype_From_Expr
(Nam
, Typ
)));
826 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
827 Set_Etype
(Nam
, Subt
);
829 -- Freeze subtype at once, to prevent order of elaboration
830 -- issues in the backend. The renamed object exists, so its
831 -- type is already frozen in any case.
833 Freeze_Before
(N
, Subt
);
836 end Check_Constrained_Object
;
838 ----------------------
839 -- In_Generic_Scope --
840 ----------------------
842 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
847 while Present
(S
) and then S
/= Standard_Standard
loop
848 if Is_Generic_Unit
(S
) then
856 end In_Generic_Scope
;
858 -- Start of processing for Analyze_Object_Renaming
865 -- The object renaming declaration may be subject to pragma Ghost with
866 -- policy Ignore. Set the mode now to ensure that any nodes generated
867 -- during analysis and expansion are properly flagged as ignored Ghost.
870 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
872 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
875 -- The renaming of a component that depends on a discriminant requires
876 -- an actual subtype, because in subsequent use of the object Gigi will
877 -- be unable to locate the actual bounds. This explicit step is required
878 -- when the renaming is generated in removing side effects of an
879 -- already-analyzed expression.
881 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
883 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
885 if Present
(Dec
) then
886 Insert_Action
(N
, Dec
);
887 T
:= Defining_Identifier
(Dec
);
891 -- Complete analysis of the subtype mark in any case, for ASIS use
893 if Present
(Subtype_Mark
(N
)) then
894 Find_Type
(Subtype_Mark
(N
));
897 elsif Present
(Subtype_Mark
(N
)) then
898 Find_Type
(Subtype_Mark
(N
));
899 T
:= Entity
(Subtype_Mark
(N
));
902 -- Reject renamings of conversions unless the type is tagged, or
903 -- the conversion is implicit (which can occur for cases of anonymous
904 -- access types in Ada 2012).
906 if Nkind
(Nam
) = N_Type_Conversion
907 and then Comes_From_Source
(Nam
)
908 and then not Is_Tagged_Type
(T
)
911 ("renaming of conversion only allowed for tagged types", Nam
);
916 -- If the renamed object is a function call of a limited type,
917 -- the expansion of the renaming is complicated by the presence
918 -- of various temporaries and subtypes that capture constraints
919 -- of the renamed object. Rewrite node as an object declaration,
920 -- whose expansion is simpler. Given that the object is limited
921 -- there is no copy involved and no performance hit.
923 if Nkind
(Nam
) = N_Function_Call
924 and then Is_Limited_View
(Etype
(Nam
))
925 and then not Is_Constrained
(Etype
(Nam
))
926 and then Comes_From_Source
(N
)
929 Set_Ekind
(Id
, E_Constant
);
931 Make_Object_Declaration
(Loc
,
932 Defining_Identifier
=> Id
,
933 Constant_Present
=> True,
934 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
935 Expression
=> Relocate_Node
(Nam
)));
939 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
940 -- when renaming declaration has a named access type. The Ada 2012
941 -- coverage rules allow an anonymous access type in the context of
942 -- an expected named general access type, but the renaming rules
943 -- require the types to be the same. (An exception is when the type
944 -- of the renaming is also an anonymous access type, which can only
945 -- happen due to a renaming created by the expander.)
947 if Nkind
(Nam
) = N_Type_Conversion
948 and then not Comes_From_Source
(Nam
)
949 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
950 and then Ekind
(T
) /= E_Anonymous_Access_Type
952 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
955 -- Check that a class-wide object is not being renamed as an object
956 -- of a specific type. The test for access types is needed to exclude
957 -- cases where the renamed object is a dynamically tagged access
958 -- result, such as occurs in certain expansions.
960 if Is_Tagged_Type
(T
) then
961 Check_Dynamically_Tagged_Expression
967 -- Ada 2005 (AI-230/AI-254): Access renaming
969 else pragma Assert
(Present
(Access_Definition
(N
)));
970 T
:= Access_Definition
972 N
=> Access_Definition
(N
));
976 -- Ada 2005 AI05-105: if the declaration has an anonymous access
977 -- type, the renamed object must also have an anonymous type, and
978 -- this is a name resolution rule. This was implicit in the last part
979 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
982 if not Is_Overloaded
(Nam
) then
983 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
985 ("expect anonymous access type in object renaming", N
);
992 Typ
: Entity_Id
:= Empty
;
993 Seen
: Boolean := False;
996 Get_First_Interp
(Nam
, I
, It
);
997 while Present
(It
.Typ
) loop
999 -- Renaming is ambiguous if more than one candidate
1000 -- interpretation is type-conformant with the context.
1002 if Ekind
(It
.Typ
) = Ekind
(T
) then
1003 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
1006 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
1012 ("ambiguous expression in renaming", Nam
);
1015 elsif Ekind
(T
) = E_Anonymous_Access_Type
1017 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1023 ("ambiguous expression in renaming", Nam
);
1027 if Covers
(T
, It
.Typ
) then
1029 Set_Etype
(Nam
, Typ
);
1030 Set_Is_Overloaded
(Nam
, False);
1034 Get_Next_Interp
(I
, It
);
1041 -- Ada 2005 (AI-231): In the case where the type is defined by an
1042 -- access_definition, the renamed entity shall be of an access-to-
1043 -- constant type if and only if the access_definition defines an
1044 -- access-to-constant type. ARM 8.5.1(4)
1046 if Constant_Present
(Access_Definition
(N
))
1047 and then not Is_Access_Constant
(Etype
(Nam
))
1049 Error_Msg_N
("(Ada 2005): the renamed object is not "
1050 & "access-to-constant (RM 8.5.1(6))", N
);
1052 elsif not Constant_Present
(Access_Definition
(N
))
1053 and then Is_Access_Constant
(Etype
(Nam
))
1055 Error_Msg_N
("(Ada 2005): the renamed object is not "
1056 & "access-to-variable (RM 8.5.1(6))", N
);
1059 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1060 Check_Subtype_Conformant
1061 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1063 elsif not Subtypes_Statically_Match
1064 (Designated_Type
(T
),
1065 Available_View
(Designated_Type
(Etype
(Nam
))))
1068 ("subtype of renamed object does not statically match", N
);
1072 -- Special processing for renaming function return object. Some errors
1073 -- and warnings are produced only for calls that come from source.
1075 if Nkind
(Nam
) = N_Function_Call
then
1078 -- Usage is illegal in Ada 83, but renamings are also introduced
1079 -- during expansion, and error does not apply to those.
1082 if Comes_From_Source
(N
) then
1084 ("(Ada 83) cannot rename function return object", Nam
);
1087 -- In Ada 95, warn for odd case of renaming parameterless function
1088 -- call if this is not a limited type (where this is useful).
1091 if Warn_On_Object_Renames_Function
1092 and then No
(Parameter_Associations
(Nam
))
1093 and then not Is_Limited_Type
(Etype
(Nam
))
1094 and then Comes_From_Source
(Nam
)
1097 ("renaming function result object is suspicious?R?", Nam
);
1099 ("\function & will be called only once?R?", Nam
,
1100 Entity
(Name
(Nam
)));
1101 Error_Msg_N
-- CODEFIX
1102 ("\suggest using an initialized constant "
1103 & "object instead?R?", Nam
);
1109 Check_Constrained_Object
;
1111 -- An object renaming requires an exact match of the type. Class-wide
1112 -- matching is not allowed.
1114 if Is_Class_Wide_Type
(T
)
1115 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1117 Wrong_Type
(Nam
, T
);
1122 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1124 if Nkind
(Nam
) = N_Explicit_Dereference
1125 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1127 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1130 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1131 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1135 -- Ada 2005 (AI-327)
1137 if Ada_Version
>= Ada_2005
1138 and then Nkind
(Nam
) = N_Attribute_Reference
1139 and then Attribute_Name
(Nam
) = Name_Priority
1143 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1146 Nam_Ent
: Entity_Id
;
1149 if Nkind
(Nam
) = N_Attribute_Reference
then
1150 Nam_Ent
:= Entity
(Prefix
(Nam
));
1152 Nam_Ent
:= Entity
(Nam
);
1155 Nam_Decl
:= Parent
(Nam_Ent
);
1157 if Has_Null_Exclusion
(N
)
1158 and then not Has_Null_Exclusion
(Nam_Decl
)
1160 -- Ada 2005 (AI-423): If the object name denotes a generic
1161 -- formal object of a generic unit G, and the object renaming
1162 -- declaration occurs within the body of G or within the body
1163 -- of a generic unit declared within the declarative region
1164 -- of G, then the declaration of the formal object of G must
1165 -- have a null exclusion or a null-excluding subtype.
1167 if Is_Formal_Object
(Nam_Ent
)
1168 and then In_Generic_Scope
(Id
)
1170 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1172 ("renamed formal does not exclude `NULL` "
1173 & "(RM 8.5.1(4.6/2))", N
);
1175 elsif In_Package_Body
(Scope
(Id
)) then
1177 ("formal object does not have a null exclusion"
1178 & "(RM 8.5.1(4.6/2))", N
);
1181 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1182 -- shall exclude null.
1184 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1186 ("renamed object does not exclude `NULL` "
1187 & "(RM 8.5.1(4.6/2))", N
);
1189 -- An instance is illegal if it contains a renaming that
1190 -- excludes null, and the actual does not. The renaming
1191 -- declaration has already indicated that the declaration
1192 -- of the renamed actual in the instance will raise
1193 -- constraint_error.
1195 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1196 and then In_Instance
1198 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1199 and then Nkind
(Expression
(Nam_Decl
)) =
1200 N_Raise_Constraint_Error
1203 ("renamed actual does not exclude `NULL` "
1204 & "(RM 8.5.1(4.6/2))", N
);
1206 -- Finally, if there is a null exclusion, the subtype mark
1207 -- must not be null-excluding.
1209 elsif No
(Access_Definition
(N
))
1210 and then Can_Never_Be_Null
(T
)
1213 ("`NOT NULL` not allowed (& already excludes null)",
1218 elsif Can_Never_Be_Null
(T
)
1219 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1222 ("renamed object does not exclude `NULL` "
1223 & "(RM 8.5.1(4.6/2))", N
);
1225 elsif Has_Null_Exclusion
(N
)
1226 and then No
(Access_Definition
(N
))
1227 and then Can_Never_Be_Null
(T
)
1230 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1235 -- Set the Ekind of the entity, unless it has been set already, as is
1236 -- the case for the iteration object over a container with no variable
1237 -- indexing. In that case it's been marked as a constant, and we do not
1238 -- want to change it to a variable.
1240 if Ekind
(Id
) /= E_Constant
then
1241 Set_Ekind
(Id
, E_Variable
);
1244 -- Initialize the object size and alignment. Note that we used to call
1245 -- Init_Size_Align here, but that's wrong for objects which have only
1246 -- an Esize, not an RM_Size field.
1248 Init_Object_Size_Align
(Id
);
1250 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1253 -- Verify that the renamed entity is an object or a function call. It
1254 -- may have been rewritten in several ways.
1256 elsif Is_Object_Reference
(Nam
) then
1257 if Comes_From_Source
(N
) then
1258 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1260 ("illegal renaming of discriminant-dependent component", Nam
);
1263 -- If the renaming comes from source and the renamed object is a
1264 -- dereference, then mark the prefix as needing debug information,
1265 -- since it might have been rewritten hence internally generated
1266 -- and Debug_Renaming_Declaration will link the renaming to it.
1268 if Nkind
(Nam
) = N_Explicit_Dereference
1269 and then Is_Entity_Name
(Prefix
(Nam
))
1271 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1275 -- A static function call may have been folded into a literal
1277 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1279 -- When expansion is disabled, attribute reference is not rewritten
1280 -- as function call. Otherwise it may be rewritten as a conversion,
1281 -- so check original node.
1283 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1284 and then Is_Function_Attribute_Name
1285 (Attribute_Name
(Original_Node
(Nam
))))
1287 -- Weird but legal, equivalent to renaming a function call. Illegal
1288 -- if the literal is the result of constant-folding an attribute
1289 -- reference that is not a function.
1291 or else (Is_Entity_Name
(Nam
)
1292 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1294 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1296 or else (Nkind
(Nam
) = N_Type_Conversion
1297 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1301 elsif Nkind
(Nam
) = N_Type_Conversion
then
1303 ("renaming of conversion only allowed for tagged types", Nam
);
1305 -- Ada 2005 (AI-327)
1307 elsif Ada_Version
>= Ada_2005
1308 and then Nkind
(Nam
) = N_Attribute_Reference
1309 and then Attribute_Name
(Nam
) = Name_Priority
1313 -- Allow internally generated x'Reference expression
1315 elsif Nkind
(Nam
) = N_Reference
then
1319 Error_Msg_N
("expect object name in renaming", Nam
);
1324 if not Is_Variable
(Nam
) then
1325 Set_Ekind
(Id
, E_Constant
);
1326 Set_Never_Set_In_Source
(Id
, True);
1327 Set_Is_True_Constant
(Id
, True);
1330 -- An object renaming is Ghost if the renamed entity is Ghost or the
1331 -- construct appears within a Ghost scope.
1333 if (Is_Entity_Name
(Nam
)
1334 and then Is_Ghost_Entity
(Entity
(Nam
)))
1335 or else Ghost_Mode
> None
1337 Set_Is_Ghost_Entity
(Id
);
1340 -- The entity of the renaming declaration needs to reflect whether the
1341 -- renamed object is volatile. Is_Volatile is set if the renamed object
1342 -- is volatile in the RM legality sense.
1344 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1346 -- Treat as volatile if we just set the Volatile flag
1350 -- Or if we are renaming an entity which was marked this way
1352 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1354 or else (Is_Entity_Name
(Nam
)
1355 and then Treat_As_Volatile
(Entity
(Nam
)))
1357 Set_Treat_As_Volatile
(Id
, True);
1360 -- Now make the link to the renamed object
1362 Set_Renamed_Object
(Id
, Nam
);
1364 -- Implementation-defined aspect specifications can appear in a renaming
1365 -- declaration, but not language-defined ones. The call to procedure
1366 -- Analyze_Aspect_Specifications will take care of this error check.
1368 if Has_Aspects
(N
) then
1369 Analyze_Aspect_Specifications
(N
, Id
);
1372 -- Deal with dimensions
1374 Analyze_Dimension
(N
);
1375 end Analyze_Object_Renaming
;
1377 ------------------------------
1378 -- Analyze_Package_Renaming --
1379 ------------------------------
1381 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1382 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1387 if Name
(N
) = Error
then
1391 -- The package renaming declaration may be subject to pragma Ghost with
1392 -- policy Ignore. Set the mode now to ensure that any nodes generated
1393 -- during analysis and expansion are properly flagged as ignored Ghost.
1397 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1399 Check_Text_IO_Special_Unit
(Name
(N
));
1401 if Current_Scope
/= Standard_Standard
then
1402 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1408 if Is_Entity_Name
(Name
(N
)) then
1409 Old_P
:= Entity
(Name
(N
));
1414 if Etype
(Old_P
) = Any_Type
then
1415 Error_Msg_N
("expect package name in renaming", Name
(N
));
1417 elsif Ekind
(Old_P
) /= E_Package
1418 and then not (Ekind
(Old_P
) = E_Generic_Package
1419 and then In_Open_Scopes
(Old_P
))
1421 if Ekind
(Old_P
) = E_Generic_Package
then
1423 ("generic package cannot be renamed as a package", Name
(N
));
1425 Error_Msg_Sloc
:= Sloc
(Old_P
);
1427 ("expect package name in renaming, found& declared#",
1431 -- Set basic attributes to minimize cascaded errors
1433 Set_Ekind
(New_P
, E_Package
);
1434 Set_Etype
(New_P
, Standard_Void_Type
);
1436 -- Here for OK package renaming
1439 -- Entities in the old package are accessible through the renaming
1440 -- entity. The simplest implementation is to have both packages share
1443 Set_Ekind
(New_P
, E_Package
);
1444 Set_Etype
(New_P
, Standard_Void_Type
);
1446 if Present
(Renamed_Object
(Old_P
)) then
1447 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1449 Set_Renamed_Object
(New_P
, Old_P
);
1452 Set_Has_Completion
(New_P
);
1454 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1455 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1456 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1457 Check_Library_Unit_Renaming
(N
, Old_P
);
1458 Generate_Reference
(Old_P
, Name
(N
));
1460 -- A package renaming is Ghost if the renamed entity is Ghost or
1461 -- the construct appears within a Ghost scope.
1463 if Is_Ghost_Entity
(Old_P
) or else Ghost_Mode
> None
then
1464 Set_Is_Ghost_Entity
(New_P
);
1467 -- If the renaming is in the visible part of a package, then we set
1468 -- Renamed_In_Spec for the renamed package, to prevent giving
1469 -- warnings about no entities referenced. Such a warning would be
1470 -- overenthusiastic, since clients can see entities in the renamed
1471 -- package via the visible package renaming.
1474 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1476 if Ekind
(Ent
) = E_Package
1477 and then not In_Private_Part
(Ent
)
1478 and then In_Extended_Main_Source_Unit
(N
)
1479 and then Ekind
(Old_P
) = E_Package
1481 Set_Renamed_In_Spec
(Old_P
);
1485 -- If this is the renaming declaration of a package instantiation
1486 -- within itself, it is the declaration that ends the list of actuals
1487 -- for the instantiation. At this point, the subtypes that rename
1488 -- the actuals are flagged as generic, to avoid spurious ambiguities
1489 -- if the actuals for two distinct formals happen to coincide. If
1490 -- the actual is a private type, the subtype has a private completion
1491 -- that is flagged in the same fashion.
1493 -- Resolution is identical to what is was in the original generic.
1494 -- On exit from the generic instance, these are turned into regular
1495 -- subtypes again, so they are compatible with types in their class.
1497 if not Is_Generic_Instance
(Old_P
) then
1500 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1503 if Nkind
(Spec
) = N_Package_Specification
1504 and then Present
(Generic_Parent
(Spec
))
1505 and then Old_P
= Current_Scope
1506 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1512 E
:= First_Entity
(Old_P
);
1513 while Present
(E
) and then E
/= New_P
loop
1515 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1517 Set_Is_Generic_Actual_Type
(E
);
1519 if Is_Private_Type
(E
)
1520 and then Present
(Full_View
(E
))
1522 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1532 -- Implementation-defined aspect specifications can appear in a renaming
1533 -- declaration, but not language-defined ones. The call to procedure
1534 -- Analyze_Aspect_Specifications will take care of this error check.
1536 if Has_Aspects
(N
) then
1537 Analyze_Aspect_Specifications
(N
, New_P
);
1539 end Analyze_Package_Renaming
;
1541 -------------------------------
1542 -- Analyze_Renamed_Character --
1543 -------------------------------
1545 procedure Analyze_Renamed_Character
1550 C
: constant Node_Id
:= Name
(N
);
1553 if Ekind
(New_S
) = E_Function
then
1554 Resolve
(C
, Etype
(New_S
));
1557 Check_Frozen_Renaming
(N
, New_S
);
1561 Error_Msg_N
("character literal can only be renamed as function", N
);
1563 end Analyze_Renamed_Character
;
1565 ---------------------------------
1566 -- Analyze_Renamed_Dereference --
1567 ---------------------------------
1569 procedure Analyze_Renamed_Dereference
1574 Nam
: constant Node_Id
:= Name
(N
);
1575 P
: constant Node_Id
:= Prefix
(Nam
);
1581 if not Is_Overloaded
(P
) then
1582 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1583 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1585 Error_Msg_N
("designated type does not match specification", P
);
1594 Get_First_Interp
(Nam
, Ind
, It
);
1596 while Present
(It
.Nam
) loop
1598 if Ekind
(It
.Nam
) = E_Subprogram_Type
1599 and then Type_Conformant
(It
.Nam
, New_S
)
1601 if Typ
/= Any_Id
then
1602 Error_Msg_N
("ambiguous renaming", P
);
1609 Get_Next_Interp
(Ind
, It
);
1612 if Typ
= Any_Type
then
1613 Error_Msg_N
("designated type does not match specification", P
);
1618 Check_Frozen_Renaming
(N
, New_S
);
1622 end Analyze_Renamed_Dereference
;
1624 ---------------------------
1625 -- Analyze_Renamed_Entry --
1626 ---------------------------
1628 procedure Analyze_Renamed_Entry
1633 Nam
: constant Node_Id
:= Name
(N
);
1634 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1635 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1639 if Entity
(Sel
) = Any_Id
then
1641 -- Selector is undefined on prefix. Error emitted already
1643 Set_Has_Completion
(New_S
);
1647 -- Otherwise find renamed entity and build body of New_S as a call to it
1649 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1651 if Old_S
= Any_Id
then
1652 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1655 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1656 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1657 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1660 -- Only mode conformance required for a renaming_as_declaration
1662 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1665 Inherit_Renamed_Profile
(New_S
, Old_S
);
1667 -- The prefix can be an arbitrary expression that yields a task or
1668 -- protected object, so it must be resolved.
1670 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1673 Set_Convention
(New_S
, Convention
(Old_S
));
1674 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1676 -- AI05-0225: If the renamed entity is a procedure or entry of a
1677 -- protected object, the target object must be a variable.
1679 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1680 and then Ekind
(New_S
) = E_Procedure
1681 and then not Is_Variable
(Prefix
(Nam
))
1685 ("target object of protected operation used as actual for "
1686 & "formal procedure must be a variable", Nam
);
1689 ("target object of protected operation renamed as procedure, "
1690 & "must be a variable", Nam
);
1695 Check_Frozen_Renaming
(N
, New_S
);
1697 end Analyze_Renamed_Entry
;
1699 -----------------------------------
1700 -- Analyze_Renamed_Family_Member --
1701 -----------------------------------
1703 procedure Analyze_Renamed_Family_Member
1708 Nam
: constant Node_Id
:= Name
(N
);
1709 P
: constant Node_Id
:= Prefix
(Nam
);
1713 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1714 or else (Nkind
(P
) = N_Selected_Component
1715 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1717 if Is_Entity_Name
(P
) then
1718 Old_S
:= Entity
(P
);
1720 Old_S
:= Entity
(Selector_Name
(P
));
1723 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1724 Error_Msg_N
("entry family does not match specification", N
);
1727 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1728 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1729 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1733 Error_Msg_N
("no entry family matches specification", N
);
1736 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1739 Check_Frozen_Renaming
(N
, New_S
);
1741 end Analyze_Renamed_Family_Member
;
1743 -----------------------------------------
1744 -- Analyze_Renamed_Primitive_Operation --
1745 -----------------------------------------
1747 procedure Analyze_Renamed_Primitive_Operation
1756 Ctyp
: Conformance_Type
) return Boolean;
1757 -- Verify that the signatures of the renamed entity and the new entity
1758 -- match. The first formal of the renamed entity is skipped because it
1759 -- is the target object in any subsequent call.
1767 Ctyp
: Conformance_Type
) return Boolean
1773 if Ekind
(Subp
) /= Ekind
(New_S
) then
1777 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1778 New_F
:= First_Formal
(New_S
);
1779 while Present
(Old_F
) and then Present
(New_F
) loop
1780 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1784 if Ctyp
>= Mode_Conformant
1785 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1790 Next_Formal
(New_F
);
1791 Next_Formal
(Old_F
);
1797 -- Start of processing for Analyze_Renamed_Primitive_Operation
1800 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1801 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1803 if not Conforms
(Old_S
, Type_Conformant
) then
1808 -- Find the operation that matches the given signature
1816 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1818 while Present
(It
.Nam
) loop
1819 if Conforms
(It
.Nam
, Type_Conformant
) then
1823 Get_Next_Interp
(Ind
, It
);
1828 if Old_S
= Any_Id
then
1829 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1833 if not Conforms
(Old_S
, Subtype_Conformant
) then
1834 Error_Msg_N
("subtype conformance error in renaming", N
);
1837 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1838 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1841 -- Only mode conformance required for a renaming_as_declaration
1843 if not Conforms
(Old_S
, Mode_Conformant
) then
1844 Error_Msg_N
("mode conformance error in renaming", N
);
1847 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1848 -- view of a subprogram is intrinsic, because the compiler has
1849 -- to generate a wrapper for any call to it. If the name in a
1850 -- subprogram renaming is a prefixed view, the entity is thus
1851 -- intrinsic, and 'Access cannot be applied to it.
1853 Set_Convention
(New_S
, Convention_Intrinsic
);
1856 -- Inherit_Renamed_Profile (New_S, Old_S);
1858 -- The prefix can be an arbitrary expression that yields an
1859 -- object, so it must be resolved.
1861 Resolve
(Prefix
(Name
(N
)));
1863 end Analyze_Renamed_Primitive_Operation
;
1865 ---------------------------------
1866 -- Analyze_Subprogram_Renaming --
1867 ---------------------------------
1869 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1870 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1871 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1872 Nam
: constant Node_Id
:= Name
(N
);
1873 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1874 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1875 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1876 Spec
: constant Node_Id
:= Specification
(N
);
1878 Old_S
: Entity_Id
:= Empty
;
1879 Rename_Spec
: Entity_Id
;
1881 procedure Build_Class_Wide_Wrapper
1882 (Ren_Id
: out Entity_Id
;
1883 Wrap_Id
: out Entity_Id
);
1884 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1885 -- type with unknown discriminants and a generic primitive operation of
1886 -- the said type with a box require special processing when the actual
1887 -- is a class-wide type:
1890 -- type Formal_Typ (<>) is private;
1891 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1892 -- package Gen is ...
1894 -- package Inst is new Gen (Actual_Typ'Class);
1896 -- In this case the general renaming mechanism used in the prologue of
1897 -- an instance no longer applies:
1899 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1901 -- The above is replaced the following wrapper/renaming combination:
1903 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1905 -- Prim_Op (Param); -- primitive
1908 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1910 -- This transformation applies only if there is no explicit visible
1911 -- class-wide operation at the point of the instantiation. Ren_Id is
1912 -- the entity of the renaming declaration. Wrap_Id is the entity of
1913 -- the generated class-wide wrapper (or Any_Id).
1915 procedure Check_Null_Exclusion
1918 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1919 -- following AI rules:
1921 -- If Ren is a renaming of a formal subprogram and one of its
1922 -- parameters has a null exclusion, then the corresponding formal
1923 -- in Sub must also have one. Otherwise the subtype of the Sub's
1924 -- formal parameter must exclude null.
1926 -- If Ren is a renaming of a formal function and its return
1927 -- profile has a null exclusion, then Sub's return profile must
1928 -- have one. Otherwise the subtype of Sub's return profile must
1931 procedure Freeze_Actual_Profile
;
1932 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1933 -- types: a callable entity freezes its profile, unless it has an
1934 -- incomplete untagged formal (RM 13.14(10.2/3)).
1936 function Has_Class_Wide_Actual
return Boolean;
1937 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1938 -- defaulted formal subprogram where the actual for the controlling
1939 -- formal type is class-wide.
1941 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1942 -- Find renamed entity when the declaration is a renaming_as_body and
1943 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1944 -- rule that a renaming_as_body is illegal if the declaration occurs
1945 -- before the subprogram it completes is frozen, and renaming indirectly
1946 -- renames the subprogram itself.(Defect Report 8652/0027).
1948 ------------------------------
1949 -- Build_Class_Wide_Wrapper --
1950 ------------------------------
1952 procedure Build_Class_Wide_Wrapper
1953 (Ren_Id
: out Entity_Id
;
1954 Wrap_Id
: out Entity_Id
)
1956 Loc
: constant Source_Ptr
:= Sloc
(N
);
1959 (Subp_Id
: Entity_Id
;
1960 Params
: List_Id
) return Node_Id
;
1961 -- Create a dispatching call to invoke routine Subp_Id with actuals
1962 -- built from the parameter specifications of list Params.
1964 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1965 -- Create a subprogram specification based on the subprogram profile
1968 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1969 -- Find a primitive subprogram of type Typ which matches the profile
1970 -- of the renaming declaration.
1972 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
1973 -- Emit a continuation error message suggesting subprogram Subp_Id as
1974 -- a possible interpretation.
1976 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
1977 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
1980 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
1981 -- Determine whether subprogram Subp_Id is a suitable candidate for
1982 -- the role of a wrapped subprogram.
1989 (Subp_Id
: Entity_Id
;
1990 Params
: List_Id
) return Node_Id
1992 Actuals
: constant List_Id
:= New_List
;
1993 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
1997 -- Build the actual parameters of the call
1999 Formal
:= First
(Params
);
2000 while Present
(Formal
) loop
2002 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2007 -- return Subp_Id (Actuals);
2009 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2011 Make_Simple_Return_Statement
(Loc
,
2013 Make_Function_Call
(Loc
,
2015 Parameter_Associations
=> Actuals
));
2018 -- Subp_Id (Actuals);
2022 Make_Procedure_Call_Statement
(Loc
,
2024 Parameter_Associations
=> Actuals
);
2032 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2033 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2034 Spec_Id
: constant Entity_Id
:=
2035 Make_Defining_Identifier
(Loc
,
2036 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2039 if Ekind
(Formal_Spec
) = E_Procedure
then
2041 Make_Procedure_Specification
(Loc
,
2042 Defining_Unit_Name
=> Spec_Id
,
2043 Parameter_Specifications
=> Params
);
2046 Make_Function_Specification
(Loc
,
2047 Defining_Unit_Name
=> Spec_Id
,
2048 Parameter_Specifications
=> Params
,
2049 Result_Definition
=>
2050 New_Copy_Tree
(Result_Definition
(Spec
)));
2054 --------------------
2055 -- Find_Primitive --
2056 --------------------
2058 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2059 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2060 -- Given a specification Spec, replace all class-wide parameter
2061 -- types with reference to type Typ.
2063 -----------------------------
2064 -- Replace_Parameter_Types --
2065 -----------------------------
2067 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2069 Formal_Id
: Entity_Id
;
2070 Formal_Typ
: Node_Id
;
2073 Formal
:= First
(Parameter_Specifications
(Spec
));
2074 while Present
(Formal
) loop
2075 Formal_Id
:= Defining_Identifier
(Formal
);
2076 Formal_Typ
:= Parameter_Type
(Formal
);
2078 -- Create a new entity for each class-wide formal to prevent
2079 -- aliasing with the original renaming. Replace the type of
2080 -- such a parameter with the candidate type.
2082 if Nkind
(Formal_Typ
) = N_Identifier
2083 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2085 Set_Defining_Identifier
(Formal
,
2086 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2088 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2093 end Replace_Parameter_Types
;
2097 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2098 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2099 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2100 Subp_Id
: Entity_Id
;
2102 -- Start of processing for Find_Primitive
2105 -- Each attempt to find a suitable primitive of a particular type
2106 -- operates on its own copy of the original renaming. As a result
2107 -- the original renaming is kept decoration and side-effect free.
2109 -- Inherit the overloaded status of the renamed subprogram name
2111 if Is_Overloaded
(Nam
) then
2112 Set_Is_Overloaded
(Alt_Nam
);
2113 Save_Interps
(Nam
, Alt_Nam
);
2116 -- The copied renaming is hidden from visibility to prevent the
2117 -- pollution of the enclosing context.
2119 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2121 -- The types of all class-wide parameters must be changed to the
2124 Replace_Parameter_Types
(Alt_Spec
);
2126 -- Try to find a suitable primitive which matches the altered
2127 -- profile of the renaming specification.
2132 Nam
=> Name
(Alt_Ren
),
2133 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2134 Is_Actual
=> Is_Actual
);
2136 -- Do not return Any_Id if the resolion of the altered profile
2137 -- failed as this complicates further checks on the caller side,
2138 -- return Empty instead.
2140 if Subp_Id
= Any_Id
then
2147 --------------------------
2148 -- Interpretation_Error --
2149 --------------------------
2151 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2153 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2155 if Is_Internal
(Subp_Id
) then
2157 ("\\possible interpretation: predefined & #",
2161 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2163 end Interpretation_Error
;
2165 ---------------------------
2166 -- Is_Intrinsic_Equality --
2167 ---------------------------
2169 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2172 Ekind
(Subp_Id
) = E_Operator
2173 and then Chars
(Subp_Id
) = Name_Op_Eq
2174 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2175 end Is_Intrinsic_Equality
;
2177 ---------------------------
2178 -- Is_Suitable_Candidate --
2179 ---------------------------
2181 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2183 if No
(Subp_Id
) then
2186 -- An intrinsic subprogram is never a good candidate. This is an
2187 -- indication of a missing primitive, either defined directly or
2188 -- inherited from a parent tagged type.
2190 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2196 end Is_Suitable_Candidate
;
2200 Actual_Typ
: Entity_Id
:= Empty
;
2201 -- The actual class-wide type for Formal_Typ
2203 CW_Prim_OK
: Boolean;
2204 CW_Prim_Op
: Entity_Id
;
2205 -- The class-wide subprogram (if available) which corresponds to the
2206 -- renamed generic formal subprogram.
2208 Formal_Typ
: Entity_Id
:= Empty
;
2209 -- The generic formal type with unknown discriminants
2211 Root_Prim_OK
: Boolean;
2212 Root_Prim_Op
: Entity_Id
;
2213 -- The root type primitive (if available) which corresponds to the
2214 -- renamed generic formal subprogram.
2216 Root_Typ
: Entity_Id
:= Empty
;
2217 -- The root type of Actual_Typ
2219 Body_Decl
: Node_Id
;
2221 Prim_Op
: Entity_Id
;
2222 Spec_Decl
: Node_Id
;
2224 -- Start of processing for Build_Class_Wide_Wrapper
2227 -- Analyze the specification of the renaming in case the generation
2228 -- of the class-wide wrapper fails.
2230 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2233 -- Do not attempt to build a wrapper if the renaming is in error
2235 if Error_Posted
(Nam
) then
2239 -- Analyze the renamed name, but do not resolve it. The resolution is
2240 -- completed once a suitable subprogram is found.
2244 -- When the renamed name denotes the intrinsic operator equals, the
2245 -- name must be treated as overloaded. This allows for a potential
2246 -- match against the root type's predefined equality function.
2248 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2249 Set_Is_Overloaded
(Nam
);
2250 Collect_Interps
(Nam
);
2253 -- Step 1: Find the generic formal type with unknown discriminants
2254 -- and its corresponding class-wide actual type from the renamed
2255 -- generic formal subprogram.
2257 Formal
:= First_Formal
(Formal_Spec
);
2258 while Present
(Formal
) loop
2259 if Has_Unknown_Discriminants
(Etype
(Formal
))
2260 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2261 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2263 Formal_Typ
:= Etype
(Formal
);
2264 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2265 Root_Typ
:= Etype
(Actual_Typ
);
2269 Next_Formal
(Formal
);
2272 -- The specification of the generic formal subprogram should always
2273 -- contain a formal type with unknown discriminants whose actual is
2274 -- a class-wide type, otherwise this indicates a failure in routine
2275 -- Has_Class_Wide_Actual.
2277 pragma Assert
(Present
(Formal_Typ
));
2279 -- Step 2: Find the proper class-wide subprogram or primitive which
2280 -- corresponds to the renamed generic formal subprogram.
2282 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2283 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2284 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2285 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2287 -- The class-wide actual type has two subprograms which correspond to
2288 -- the renamed generic formal subprogram:
2290 -- with procedure Prim_Op (Param : Formal_Typ);
2292 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2293 -- procedure Prim_Op (Param : Actual_Typ'Class);
2295 -- Even though the declaration of the two subprograms is legal, a
2296 -- call to either one is ambiguous and therefore illegal.
2298 if CW_Prim_OK
and Root_Prim_OK
then
2300 -- A user-defined primitive has precedence over a predefined one
2302 if Is_Internal
(CW_Prim_Op
)
2303 and then not Is_Internal
(Root_Prim_Op
)
2305 Prim_Op
:= Root_Prim_Op
;
2307 elsif Is_Internal
(Root_Prim_Op
)
2308 and then not Is_Internal
(CW_Prim_Op
)
2310 Prim_Op
:= CW_Prim_Op
;
2312 elsif CW_Prim_Op
= Root_Prim_Op
then
2313 Prim_Op
:= Root_Prim_Op
;
2315 -- Otherwise both candidate subprograms are user-defined and
2320 ("ambiguous actual for generic subprogram &",
2322 Interpretation_Error
(Root_Prim_Op
);
2323 Interpretation_Error
(CW_Prim_Op
);
2327 elsif CW_Prim_OK
and not Root_Prim_OK
then
2328 Prim_Op
:= CW_Prim_Op
;
2330 elsif not CW_Prim_OK
and Root_Prim_OK
then
2331 Prim_Op
:= Root_Prim_Op
;
2333 -- An intrinsic equality may act as a suitable candidate in the case
2334 -- of a null type extension where the parent's equality is hidden. A
2335 -- call to an intrinsic equality is expanded as dispatching.
2337 elsif Present
(Root_Prim_Op
)
2338 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2340 Prim_Op
:= Root_Prim_Op
;
2342 -- Otherwise there are no candidate subprograms. Let the caller
2343 -- diagnose the error.
2349 -- At this point resolution has taken place and the name is no longer
2350 -- overloaded. Mark the primitive as referenced.
2352 Set_Is_Overloaded
(Name
(N
), False);
2353 Set_Referenced
(Prim_Op
);
2355 -- Step 3: Create the declaration and the body of the wrapper, insert
2356 -- all the pieces into the tree.
2359 Make_Subprogram_Declaration
(Loc
,
2360 Specification
=> Build_Spec
(Ren_Id
));
2361 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2363 -- If the operator carries an Eliminated pragma, indicate that the
2364 -- wrapper is also to be eliminated, to prevent spurious error when
2365 -- using gnatelim on programs that include box-initialization of
2366 -- equality operators.
2368 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2369 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2372 Make_Subprogram_Body
(Loc
,
2373 Specification
=> Build_Spec
(Ren_Id
),
2374 Declarations
=> New_List
,
2375 Handled_Statement_Sequence
=>
2376 Make_Handled_Sequence_Of_Statements
(Loc
,
2377 Statements
=> New_List
(
2379 (Subp_Id
=> Prim_Op
,
2381 Parameter_Specifications
2382 (Specification
(Spec_Decl
))))));
2384 -- The generated body does not freeze and must be analyzed when the
2385 -- class-wide wrapper is frozen. The body is only needed if expansion
2388 if Expander_Active
then
2389 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2392 -- Step 4: The subprogram renaming aliases the wrapper
2394 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2395 end Build_Class_Wide_Wrapper
;
2397 --------------------------
2398 -- Check_Null_Exclusion --
2399 --------------------------
2401 procedure Check_Null_Exclusion
2405 Ren_Formal
: Entity_Id
;
2406 Sub_Formal
: Entity_Id
;
2411 Ren_Formal
:= First_Formal
(Ren
);
2412 Sub_Formal
:= First_Formal
(Sub
);
2413 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2414 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2416 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2417 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2420 ("`NOT NULL` required for parameter &",
2421 Parent
(Sub_Formal
), Sub_Formal
);
2424 Next_Formal
(Ren_Formal
);
2425 Next_Formal
(Sub_Formal
);
2428 -- Return profile check
2430 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2431 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2432 and then Has_Null_Exclusion
(Parent
(Ren
))
2433 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2434 or else Can_Never_Be_Null
(Etype
(Sub
)))
2437 ("return must specify `NOT NULL`",
2438 Result_Definition
(Parent
(Sub
)));
2440 end Check_Null_Exclusion
;
2442 ---------------------------
2443 -- Freeze_Actual_Profile --
2444 ---------------------------
2446 procedure Freeze_Actual_Profile
is
2448 Has_Untagged_Inc
: Boolean;
2449 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2452 if Ada_Version
>= Ada_2012
then
2453 F
:= First_Formal
(Formal_Spec
);
2454 Has_Untagged_Inc
:= False;
2455 while Present
(F
) loop
2456 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2457 and then not Is_Tagged_Type
(Etype
(F
))
2459 Has_Untagged_Inc
:= True;
2463 F
:= Next_Formal
(F
);
2466 if Ekind
(Formal_Spec
) = E_Function
2467 and then Ekind
(Etype
(Formal_Spec
)) = E_Incomplete_Type
2468 and then not Is_Tagged_Type
(Etype
(F
))
2470 Has_Untagged_Inc
:= True;
2473 if not Has_Untagged_Inc
then
2474 F
:= First_Formal
(Old_S
);
2475 while Present
(F
) loop
2476 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2478 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2479 and then No
(Underlying_Type
(Etype
(F
)))
2481 -- Exclude generic types, or types derived from them.
2482 -- They will be frozen in the enclosing instance.
2484 if Is_Generic_Type
(Etype
(F
))
2485 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2490 ("type& must be frozen before this point",
2491 Instantiation_Node
, Etype
(F
));
2495 F
:= Next_Formal
(F
);
2499 end Freeze_Actual_Profile
;
2501 ---------------------------
2502 -- Has_Class_Wide_Actual --
2503 ---------------------------
2505 function Has_Class_Wide_Actual
return Boolean is
2507 Formal_Typ
: Entity_Id
;
2511 Formal
:= First_Formal
(Formal_Spec
);
2512 while Present
(Formal
) loop
2513 Formal_Typ
:= Etype
(Formal
);
2515 if Has_Unknown_Discriminants
(Formal_Typ
)
2516 and then not Is_Class_Wide_Type
(Formal_Typ
)
2517 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2522 Next_Formal
(Formal
);
2527 end Has_Class_Wide_Actual
;
2529 -------------------------
2530 -- Original_Subprogram --
2531 -------------------------
2533 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2534 Orig_Decl
: Node_Id
;
2535 Orig_Subp
: Entity_Id
;
2538 -- First case: renamed entity is itself a renaming
2540 if Present
(Alias
(Subp
)) then
2541 return Alias
(Subp
);
2543 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2544 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2546 -- Check if renamed entity is a renaming_as_body
2549 Unit_Declaration_Node
2550 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2552 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2553 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2555 if Orig_Subp
= Rename_Spec
then
2557 -- Circularity detected
2562 return (Original_Subprogram
(Orig_Subp
));
2570 end Original_Subprogram
;
2574 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2575 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2576 -- defaulted formal subprogram when the actual for a related formal
2577 -- type is class-wide.
2579 Inst_Node
: Node_Id
:= Empty
;
2582 -- Start of processing for Analyze_Subprogram_Renaming
2585 -- The subprogram renaming declaration may be subject to pragma Ghost
2586 -- with policy Ignore. Set the mode now to ensure that any nodes
2587 -- generated during analysis and expansion are properly flagged as
2592 -- We must test for the attribute renaming case before the Analyze
2593 -- call because otherwise Sem_Attr will complain that the attribute
2594 -- is missing an argument when it is analyzed.
2596 if Nkind
(Nam
) = N_Attribute_Reference
then
2598 -- In the case of an abstract formal subprogram association, rewrite
2599 -- an actual given by a stream attribute as the name of the
2600 -- corresponding stream primitive of the type.
2602 -- In a generic context the stream operations are not generated, and
2603 -- this must be treated as a normal attribute reference, to be
2604 -- expanded in subsequent instantiations.
2607 and then Is_Abstract_Subprogram
(Formal_Spec
)
2608 and then Expander_Active
2611 Stream_Prim
: Entity_Id
;
2612 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2615 -- The class-wide forms of the stream attributes are not
2616 -- primitive dispatching operations (even though they
2617 -- internally dispatch to a stream attribute).
2619 if Is_Class_Wide_Type
(Prefix_Type
) then
2621 ("attribute must be a primitive dispatching operation",
2626 -- Retrieve the primitive subprogram associated with the
2627 -- attribute. This can only be a stream attribute, since those
2628 -- are the only ones that are dispatching (and the actual for
2629 -- an abstract formal subprogram must be dispatching
2633 case Attribute_Name
(Nam
) is
2636 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2639 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2642 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2645 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2648 ("attribute must be a primitive"
2649 & " dispatching operation", Nam
);
2655 -- If no operation was found, and the type is limited,
2656 -- the user should have defined one.
2658 when Program_Error
=>
2659 if Is_Limited_Type
(Prefix_Type
) then
2661 ("stream operation not defined for type&",
2665 -- Otherwise, compiler should have generated default
2672 -- Rewrite the attribute into the name of its corresponding
2673 -- primitive dispatching subprogram. We can then proceed with
2674 -- the usual processing for subprogram renamings.
2677 Prim_Name
: constant Node_Id
:=
2678 Make_Identifier
(Sloc
(Nam
),
2679 Chars
=> Chars
(Stream_Prim
));
2681 Set_Entity
(Prim_Name
, Stream_Prim
);
2682 Rewrite
(Nam
, Prim_Name
);
2687 -- Normal processing for a renaming of an attribute
2690 Attribute_Renaming
(N
);
2695 -- Check whether this declaration corresponds to the instantiation
2696 -- of a formal subprogram.
2698 -- If this is an instantiation, the corresponding actual is frozen and
2699 -- error messages can be made more precise. If this is a default
2700 -- subprogram, the entity is already established in the generic, and is
2701 -- not retrieved by visibility. If it is a default with a box, the
2702 -- candidate interpretations, if any, have been collected when building
2703 -- the renaming declaration. If overloaded, the proper interpretation is
2704 -- determined in Find_Renamed_Entity. If the entity is an operator,
2705 -- Find_Renamed_Entity applies additional visibility checks.
2708 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2710 -- Check whether the renaming is for a defaulted actual subprogram
2711 -- with a class-wide actual.
2713 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2714 -- is an external axiomatization on the package.
2717 and then Box_Present
(Inst_Node
)
2721 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2723 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2725 elsif Is_Entity_Name
(Nam
)
2726 and then Present
(Entity
(Nam
))
2727 and then not Comes_From_Source
(Nam
)
2728 and then not Is_Overloaded
(Nam
)
2730 Old_S
:= Entity
(Nam
);
2731 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2735 if Ekind
(Entity
(Nam
)) = E_Operator
then
2739 if Box_Present
(Inst_Node
) then
2740 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2742 -- If there is an immediately visible homonym of the operator
2743 -- and the declaration has a default, this is worth a warning
2744 -- because the user probably did not intend to get the pre-
2745 -- defined operator, visible in the generic declaration. To
2746 -- find if there is an intended candidate, analyze the renaming
2747 -- again in the current context.
2749 elsif Scope
(Old_S
) = Standard_Standard
2750 and then Present
(Default_Name
(Inst_Node
))
2753 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2757 Set_Entity
(Name
(Decl
), Empty
);
2758 Analyze
(Name
(Decl
));
2760 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2763 and then In_Open_Scopes
(Scope
(Hidden
))
2764 and then Is_Immediately_Visible
(Hidden
)
2765 and then Comes_From_Source
(Hidden
)
2766 and then Hidden
/= Old_S
2768 Error_Msg_Sloc
:= Sloc
(Hidden
);
2769 Error_Msg_N
("default subprogram is resolved " &
2770 "in the generic declaration " &
2771 "(RM 12.6(17))??", N
);
2772 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2780 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2784 -- Renamed entity must be analyzed first, to avoid being hidden by
2785 -- new name (which might be the same in a generic instance).
2789 -- The renaming defines a new overloaded entity, which is analyzed
2790 -- like a subprogram declaration.
2792 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2795 if Current_Scope
/= Standard_Standard
then
2796 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2799 -- Set SPARK mode from current context
2801 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2802 Set_SPARK_Pragma_Inherited
(New_S
, True);
2804 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2806 -- Case of Renaming_As_Body
2808 if Present
(Rename_Spec
) then
2810 -- Renaming declaration is the completion of the declaration of
2811 -- Rename_Spec. We build an actual body for it at the freezing point.
2813 Set_Corresponding_Spec
(N
, Rename_Spec
);
2815 -- Deal with special case of stream functions of abstract types
2818 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2819 N_Abstract_Subprogram_Declaration
2821 -- Input stream functions are abstract if the object type is
2822 -- abstract. Similarly, all default stream functions for an
2823 -- interface type are abstract. However, these subprograms may
2824 -- receive explicit declarations in representation clauses, making
2825 -- the attribute subprograms usable as defaults in subsequent
2827 -- In this case we rewrite the declaration to make the subprogram
2828 -- non-abstract. We remove the previous declaration, and insert
2829 -- the new one at the point of the renaming, to prevent premature
2830 -- access to unfrozen types. The new declaration reuses the
2831 -- specification of the previous one, and must not be analyzed.
2834 (Is_Primitive
(Entity
(Nam
))
2836 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2838 Old_Decl
: constant Node_Id
:=
2839 Unit_Declaration_Node
(Rename_Spec
);
2840 New_Decl
: constant Node_Id
:=
2841 Make_Subprogram_Declaration
(Sloc
(N
),
2843 Relocate_Node
(Specification
(Old_Decl
)));
2846 Insert_After
(N
, New_Decl
);
2847 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2848 Set_Analyzed
(New_Decl
);
2852 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2854 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2855 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2858 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2859 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2860 Set_Public_Status
(New_S
);
2862 -- The specification does not introduce new formals, but only
2863 -- repeats the formals of the original subprogram declaration.
2864 -- For cross-reference purposes, and for refactoring tools, we
2865 -- treat the formals of the renaming declaration as body formals.
2867 Reference_Body_Formals
(Rename_Spec
, New_S
);
2869 -- Indicate that the entity in the declaration functions like the
2870 -- corresponding body, and is not a new entity. The body will be
2871 -- constructed later at the freeze point, so indicate that the
2872 -- completion has not been seen yet.
2874 Set_Ekind
(New_S
, E_Subprogram_Body
);
2875 New_S
:= Rename_Spec
;
2876 Set_Has_Completion
(Rename_Spec
, False);
2878 -- Ada 2005: check overriding indicator
2880 if Present
(Overridden_Operation
(Rename_Spec
)) then
2881 if Must_Not_Override
(Specification
(N
)) then
2883 ("subprogram& overrides inherited operation",
2886 Style_Check
and then not Must_Override
(Specification
(N
))
2888 Style
.Missing_Overriding
(N
, Rename_Spec
);
2891 elsif Must_Override
(Specification
(N
)) then
2892 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2895 -- Normal subprogram renaming (not renaming as body)
2898 Generate_Definition
(New_S
);
2899 New_Overloaded_Entity
(New_S
);
2901 if Is_Entity_Name
(Nam
)
2902 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2906 Check_Delayed_Subprogram
(New_S
);
2910 -- There is no need for elaboration checks on the new entity, which may
2911 -- be called before the next freezing point where the body will appear.
2912 -- Elaboration checks refer to the real entity, not the one created by
2913 -- the renaming declaration.
2915 Set_Kill_Elaboration_Checks
(New_S
, True);
2917 -- If we had a previous error, indicate a completely is present to stop
2918 -- junk cascaded messages, but don't take any further action.
2920 if Etype
(Nam
) = Any_Type
then
2921 Set_Has_Completion
(New_S
);
2924 -- Case where name has the form of a selected component
2926 elsif Nkind
(Nam
) = N_Selected_Component
then
2928 -- A name which has the form A.B can designate an entry of task A, a
2929 -- protected operation of protected object A, or finally a primitive
2930 -- operation of object A. In the later case, A is an object of some
2931 -- tagged type, or an access type that denotes one such. To further
2932 -- distinguish these cases, note that the scope of a task entry or
2933 -- protected operation is type of the prefix.
2935 -- The prefix could be an overloaded function call that returns both
2936 -- kinds of operations. This overloading pathology is left to the
2937 -- dedicated reader ???
2940 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2948 and then Is_Tagged_Type
(Designated_Type
(T
))))
2949 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2951 Analyze_Renamed_Primitive_Operation
2952 (N
, New_S
, Present
(Rename_Spec
));
2956 -- Renamed entity is an entry or protected operation. For those
2957 -- cases an explicit body is built (at the point of freezing of
2958 -- this entity) that contains a call to the renamed entity.
2960 -- This is not allowed for renaming as body if the renamed
2961 -- spec is already frozen (see RM 8.5.4(5) for details).
2963 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
2965 ("renaming-as-body cannot rename entry as subprogram", N
);
2967 ("\since & is already frozen (RM 8.5.4(5))",
2970 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
2977 -- Case where name is an explicit dereference X.all
2979 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
2981 -- Renamed entity is designated by access_to_subprogram expression.
2982 -- Must build body to encapsulate call, as in the entry case.
2984 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
2987 -- Indexed component
2989 elsif Nkind
(Nam
) = N_Indexed_Component
then
2990 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
2993 -- Character literal
2995 elsif Nkind
(Nam
) = N_Character_Literal
then
2996 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
2999 -- Only remaining case is where we have a non-entity name, or a renaming
3000 -- of some other non-overloadable entity.
3002 elsif not Is_Entity_Name
(Nam
)
3003 or else not Is_Overloadable
(Entity
(Nam
))
3005 -- Do not mention the renaming if it comes from an instance
3007 if not Is_Actual
then
3008 Error_Msg_N
("expect valid subprogram name in renaming", N
);
3010 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3016 -- Find the renamed entity that matches the given specification. Disable
3017 -- Ada_83 because there is no requirement of full conformance between
3018 -- renamed entity and new entity, even though the same circuit is used.
3020 -- This is a bit of an odd case, which introduces a really irregular use
3021 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3024 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3025 Ada_Version_Pragma
:= Empty
;
3026 Ada_Version_Explicit
:= Ada_Version
;
3029 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3031 -- The visible operation may be an inherited abstract operation that
3032 -- was overridden in the private part, in which case a call will
3033 -- dispatch to the overriding operation. Use the overriding one in
3034 -- the renaming declaration, to prevent spurious errors below.
3036 if Is_Overloadable
(Old_S
)
3037 and then Is_Abstract_Subprogram
(Old_S
)
3038 and then No
(DTC_Entity
(Old_S
))
3039 and then Present
(Alias
(Old_S
))
3040 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3041 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3043 Old_S
:= Alias
(Old_S
);
3046 -- When the renamed subprogram is overloaded and used as an actual
3047 -- of a generic, its entity is set to the first available homonym.
3048 -- We must first disambiguate the name, then set the proper entity.
3050 if Is_Actual
and then Is_Overloaded
(Nam
) then
3051 Set_Entity
(Nam
, Old_S
);
3055 -- Most common case: subprogram renames subprogram. No body is generated
3056 -- in this case, so we must indicate the declaration is complete as is.
3057 -- and inherit various attributes of the renamed subprogram.
3059 if No
(Rename_Spec
) then
3060 Set_Has_Completion
(New_S
);
3061 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3062 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3063 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3065 -- A subprogram renaming is Ghost if the renamed entity is Ghost or
3066 -- the construct appears within a Ghost scope.
3068 if Is_Ghost_Entity
(Entity
(Nam
)) or else Ghost_Mode
> None
then
3069 Set_Is_Ghost_Entity
(New_S
);
3072 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3073 -- between a subprogram and its correct renaming.
3075 -- Note: the Any_Id check is a guard that prevents compiler crashes
3076 -- when performing a null exclusion check between a renaming and a
3077 -- renamed subprogram that has been found to be illegal.
3079 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3080 Check_Null_Exclusion
3082 Sub
=> Entity
(Nam
));
3085 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3086 -- overriding. The flag Requires_Overriding is set very selectively
3087 -- and misses some other illegal cases. The additional conditions
3088 -- checked below are sufficient but not necessary ???
3090 -- The rule does not apply to the renaming generated for an actual
3091 -- subprogram in an instance.
3096 -- Guard against previous errors, and omit renamings of predefined
3099 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3102 elsif Requires_Overriding
(Old_S
)
3104 (Is_Abstract_Subprogram
(Old_S
)
3105 and then Present
(Find_Dispatching_Type
(Old_S
))
3107 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3110 ("renamed entity cannot be "
3111 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3115 if Old_S
/= Any_Id
then
3116 if Is_Actual
and then From_Default
(N
) then
3118 -- This is an implicit reference to the default actual
3120 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3123 Generate_Reference
(Old_S
, Nam
);
3126 Check_Internal_Protected_Use
(N
, Old_S
);
3128 -- For a renaming-as-body, require subtype conformance, but if the
3129 -- declaration being completed has not been frozen, then inherit the
3130 -- convention of the renamed subprogram prior to checking conformance
3131 -- (unless the renaming has an explicit convention established; the
3132 -- rule stated in the RM doesn't seem to address this ???).
3134 if Present
(Rename_Spec
) then
3135 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3136 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3138 if not Is_Frozen
(Rename_Spec
) then
3139 if not Has_Convention_Pragma
(Rename_Spec
) then
3140 Set_Convention
(New_S
, Convention
(Old_S
));
3143 if Ekind
(Old_S
) /= E_Operator
then
3144 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3147 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3148 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3151 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3154 Check_Frozen_Renaming
(N
, Rename_Spec
);
3156 -- Check explicitly that renamed entity is not intrinsic, because
3157 -- in a generic the renamed body is not built. In this case,
3158 -- the renaming_as_body is a completion.
3160 if Inside_A_Generic
then
3161 if Is_Frozen
(Rename_Spec
)
3162 and then Is_Intrinsic_Subprogram
(Old_S
)
3165 ("subprogram in renaming_as_body cannot be intrinsic",
3169 Set_Has_Completion
(Rename_Spec
);
3172 elsif Ekind
(Old_S
) /= E_Operator
then
3174 -- If this a defaulted subprogram for a class-wide actual there is
3175 -- no check for mode conformance, given that the signatures don't
3176 -- match (the source mentions T but the actual mentions T'Class).
3180 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3181 Check_Mode_Conformant
(New_S
, Old_S
);
3184 if Is_Actual
and then Error_Posted
(New_S
) then
3185 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3189 if No
(Rename_Spec
) then
3191 -- The parameter profile of the new entity is that of the renamed
3192 -- entity: the subtypes given in the specification are irrelevant.
3194 Inherit_Renamed_Profile
(New_S
, Old_S
);
3196 -- A call to the subprogram is transformed into a call to the
3197 -- renamed entity. This is transitive if the renamed entity is
3198 -- itself a renaming.
3200 if Present
(Alias
(Old_S
)) then
3201 Set_Alias
(New_S
, Alias
(Old_S
));
3203 Set_Alias
(New_S
, Old_S
);
3206 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3207 -- renaming as body, since the entity in this case is not an
3208 -- intrinsic (it calls an intrinsic, but we have a real body for
3209 -- this call, and it is in this body that the required intrinsic
3210 -- processing will take place).
3212 -- Also, if this is a renaming of inequality, the renamed operator
3213 -- is intrinsic, but what matters is the corresponding equality
3214 -- operator, which may be user-defined.
3216 Set_Is_Intrinsic_Subprogram
3218 Is_Intrinsic_Subprogram
(Old_S
)
3220 (Chars
(Old_S
) /= Name_Op_Ne
3221 or else Ekind
(Old_S
) = E_Operator
3222 or else Is_Intrinsic_Subprogram
3223 (Corresponding_Equality
(Old_S
))));
3225 if Ekind
(Alias
(New_S
)) = E_Operator
then
3226 Set_Has_Delayed_Freeze
(New_S
, False);
3229 -- If the renaming corresponds to an association for an abstract
3230 -- formal subprogram, then various attributes must be set to
3231 -- indicate that the renaming is an abstract dispatching operation
3232 -- with a controlling type.
3234 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3236 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3237 -- see it as corresponding to a generic association for a
3238 -- formal abstract subprogram
3240 Set_Is_Abstract_Subprogram
(New_S
);
3243 New_S_Ctrl_Type
: constant Entity_Id
:=
3244 Find_Dispatching_Type
(New_S
);
3245 Old_S_Ctrl_Type
: constant Entity_Id
:=
3246 Find_Dispatching_Type
(Old_S
);
3249 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
3251 ("actual must be dispatching subprogram for type&",
3252 Nam
, New_S_Ctrl_Type
);
3255 Set_Is_Dispatching_Operation
(New_S
);
3256 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3258 -- If the actual in the formal subprogram is itself a
3259 -- formal abstract subprogram association, there's no
3260 -- dispatch table component or position to inherit.
3262 if Present
(DTC_Entity
(Old_S
)) then
3263 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3264 Set_DT_Position
(New_S
, DT_Position
(Old_S
));
3274 -- The following is illegal, because F hides whatever other F may
3276 -- function F (...) renames F;
3279 or else (Nkind
(Nam
) /= N_Expanded_Name
3280 and then Chars
(Old_S
) = Chars
(New_S
))
3282 Error_Msg_N
("subprogram cannot rename itself", N
);
3284 -- This is illegal even if we use a selector:
3285 -- function F (...) renames Pkg.F;
3286 -- because F is still hidden.
3288 elsif Nkind
(Nam
) = N_Expanded_Name
3289 and then Entity
(Prefix
(Nam
)) = Current_Scope
3290 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3292 -- This is an error, but we overlook the error and accept the
3293 -- renaming if the special Overriding_Renamings mode is in effect.
3295 if not Overriding_Renamings
then
3297 ("implicit operation& is not visible (RM 8.3 (15))",
3302 Set_Convention
(New_S
, Convention
(Old_S
));
3304 if Is_Abstract_Subprogram
(Old_S
) then
3305 if Present
(Rename_Spec
) then
3307 ("a renaming-as-body cannot rename an abstract subprogram",
3309 Set_Has_Completion
(Rename_Spec
);
3311 Set_Is_Abstract_Subprogram
(New_S
);
3315 Check_Library_Unit_Renaming
(N
, Old_S
);
3317 -- Pathological case: procedure renames entry in the scope of its
3318 -- task. Entry is given by simple name, but body must be built for
3319 -- procedure. Of course if called it will deadlock.
3321 if Ekind
(Old_S
) = E_Entry
then
3322 Set_Has_Completion
(New_S
, False);
3323 Set_Alias
(New_S
, Empty
);
3327 Freeze_Before
(N
, Old_S
);
3328 Freeze_Actual_Profile
;
3329 Set_Has_Delayed_Freeze
(New_S
, False);
3330 Freeze_Before
(N
, New_S
);
3332 -- An abstract subprogram is only allowed as an actual in the case
3333 -- where the formal subprogram is also abstract.
3335 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3336 and then Is_Abstract_Subprogram
(Old_S
)
3337 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3340 ("abstract subprogram not allowed as generic actual", Nam
);
3345 -- A common error is to assume that implicit operators for types are
3346 -- defined in Standard, or in the scope of a subtype. In those cases
3347 -- where the renamed entity is given with an expanded name, it is
3348 -- worth mentioning that operators for the type are not declared in
3349 -- the scope given by the prefix.
3351 if Nkind
(Nam
) = N_Expanded_Name
3352 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3353 and then Scope
(Entity
(Nam
)) = Standard_Standard
3356 T
: constant Entity_Id
:=
3357 Base_Type
(Etype
(First_Formal
(New_S
)));
3359 Error_Msg_Node_2
:= Prefix
(Nam
);
3361 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3366 ("no visible subprogram matches the specification for&",
3370 if Present
(Candidate_Renaming
) then
3377 F1
:= First_Formal
(Candidate_Renaming
);
3378 F2
:= First_Formal
(New_S
);
3379 T1
:= First_Subtype
(Etype
(F1
));
3380 while Present
(F1
) and then Present
(F2
) loop
3385 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3386 if Present
(Next_Formal
(F1
)) then
3388 ("\missing specification for &" &
3389 " and other formals with defaults", Spec
, F1
);
3392 ("\missing specification for &", Spec
, F1
);
3396 if Nkind
(Nam
) = N_Operator_Symbol
3397 and then From_Default
(N
)
3399 Error_Msg_Node_2
:= T1
;
3401 ("default & on & is not directly visible",
3408 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3409 -- controlling access parameters are known non-null for the renamed
3410 -- subprogram. Test also applies to a subprogram instantiation that
3411 -- is dispatching. Test is skipped if some previous error was detected
3412 -- that set Old_S to Any_Id.
3414 if Ada_Version
>= Ada_2005
3415 and then Old_S
/= Any_Id
3416 and then not Is_Dispatching_Operation
(Old_S
)
3417 and then Is_Dispatching_Operation
(New_S
)
3424 Old_F
:= First_Formal
(Old_S
);
3425 New_F
:= First_Formal
(New_S
);
3426 while Present
(Old_F
) loop
3427 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3428 and then Is_Controlling_Formal
(New_F
)
3429 and then not Can_Never_Be_Null
(Old_F
)
3431 Error_Msg_N
("access parameter is controlling,", New_F
);
3433 ("\corresponding parameter of& "
3434 & "must be explicitly null excluding", New_F
, Old_S
);
3437 Next_Formal
(Old_F
);
3438 Next_Formal
(New_F
);
3443 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3444 -- is to warn if an operator is being renamed as a different operator.
3445 -- If the operator is predefined, examine the kind of the entity, not
3446 -- the abbreviated declaration in Standard.
3448 if Comes_From_Source
(N
)
3449 and then Present
(Old_S
)
3450 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3451 or else Ekind
(Old_S
) = E_Operator
)
3452 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3453 and then Chars
(Old_S
) /= Chars
(New_S
)
3456 ("& is being renamed as a different operator??", N
, Old_S
);
3459 -- Check for renaming of obsolescent subprogram
3461 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3463 -- Another warning or some utility: if the new subprogram as the same
3464 -- name as the old one, the old one is not hidden by an outer homograph,
3465 -- the new one is not a public symbol, and the old one is otherwise
3466 -- directly visible, the renaming is superfluous.
3468 if Chars
(Old_S
) = Chars
(New_S
)
3469 and then Comes_From_Source
(N
)
3470 and then Scope
(Old_S
) /= Standard_Standard
3471 and then Warn_On_Redundant_Constructs
3472 and then (Is_Immediately_Visible
(Old_S
)
3473 or else Is_Potentially_Use_Visible
(Old_S
))
3474 and then Is_Overloadable
(Current_Scope
)
3475 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3478 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3481 -- Implementation-defined aspect specifications can appear in a renaming
3482 -- declaration, but not language-defined ones. The call to procedure
3483 -- Analyze_Aspect_Specifications will take care of this error check.
3485 if Has_Aspects
(N
) then
3486 Analyze_Aspect_Specifications
(N
, New_S
);
3489 Ada_Version
:= Save_AV
;
3490 Ada_Version_Pragma
:= Save_AVP
;
3491 Ada_Version_Explicit
:= Save_AV_Exp
;
3493 -- In GNATprove mode, the renamings of actual subprograms are replaced
3494 -- with wrapper functions that make it easier to propagate axioms to the
3495 -- points of call within an instance. Wrappers are generated if formal
3496 -- subprogram is subject to axiomatization.
3498 -- The types in the wrapper profiles are obtained from (instances of)
3499 -- the types of the formal subprogram.
3502 and then GNATprove_Mode
3503 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3504 and then not Inside_A_Generic
3506 if Ekind
(Old_S
) = E_Function
then
3507 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3510 elsif Ekind
(Old_S
) = E_Operator
then
3511 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3515 end Analyze_Subprogram_Renaming
;
3517 -------------------------
3518 -- Analyze_Use_Package --
3519 -------------------------
3521 -- Resolve the package names in the use clause, and make all the visible
3522 -- entities defined in the package potentially use-visible. If the package
3523 -- is already in use from a previous use clause, its visible entities are
3524 -- already use-visible. In that case, mark the occurrence as a redundant
3525 -- use. If the package is an open scope, i.e. if the use clause occurs
3526 -- within the package itself, ignore it.
3528 procedure Analyze_Use_Package
(N
: Node_Id
) is
3529 Pack_Name
: Node_Id
;
3532 -- Start of processing for Analyze_Use_Package
3535 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3537 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3539 -- Use clause not allowed in a spec of a predefined package declaration
3540 -- except that packages whose file name starts a-n are OK (these are
3541 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3543 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3544 and then Name_Buffer
(1 .. 3) /= "a-n"
3546 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3548 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3551 -- Chain clause to list of use clauses in current scope
3553 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3554 Chain_Use_Clause
(N
);
3557 -- Loop through package names to identify referenced packages
3559 Pack_Name
:= First
(Names
(N
));
3560 while Present
(Pack_Name
) loop
3561 Analyze
(Pack_Name
);
3563 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3564 and then Nkind
(Pack_Name
) = N_Expanded_Name
3570 Pref
:= Prefix
(Pack_Name
);
3571 while Nkind
(Pref
) = N_Expanded_Name
loop
3572 Pref
:= Prefix
(Pref
);
3575 if Entity
(Pref
) = Standard_Standard
then
3577 ("predefined package Standard cannot appear"
3578 & " in a context clause", Pref
);
3586 -- Loop through package names to mark all entities as potentially
3589 Pack_Name
:= First
(Names
(N
));
3590 while Present
(Pack_Name
) loop
3591 if Is_Entity_Name
(Pack_Name
) then
3592 Pack
:= Entity
(Pack_Name
);
3594 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3595 if Ekind
(Pack
) = E_Generic_Package
then
3596 Error_Msg_N
-- CODEFIX
3597 ("a generic package is not allowed in a use clause",
3600 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3602 Error_Msg_N
-- CODEFIX
3603 ("a generic subprogram is not allowed in a use clause",
3606 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3607 Error_Msg_N
-- CODEFIX
3608 ("a subprogram is not allowed in a use clause",
3612 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3616 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3617 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3620 if Applicable_Use
(Pack_Name
) then
3621 Use_One_Package
(Pack
, N
);
3625 -- Report error because name denotes something other than a package
3628 Error_Msg_N
("& is not a package", Pack_Name
);
3633 end Analyze_Use_Package
;
3635 ----------------------
3636 -- Analyze_Use_Type --
3637 ----------------------
3639 procedure Analyze_Use_Type
(N
: Node_Id
) is
3644 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3646 -- Chain clause to list of use clauses in current scope
3648 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3649 Chain_Use_Clause
(N
);
3652 -- If the Used_Operations list is already initialized, the clause has
3653 -- been analyzed previously, and it is begin reinstalled, for example
3654 -- when the clause appears in a package spec and we are compiling the
3655 -- corresponding package body. In that case, make the entities on the
3656 -- existing list use_visible, and mark the corresponding types In_Use.
3658 if Present
(Used_Operations
(N
)) then
3664 Mark
:= First
(Subtype_Marks
(N
));
3665 while Present
(Mark
) loop
3666 Use_One_Type
(Mark
, Installed
=> True);
3670 Elmt
:= First_Elmt
(Used_Operations
(N
));
3671 while Present
(Elmt
) loop
3672 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3680 -- Otherwise, create new list and attach to it the operations that
3681 -- are made use-visible by the clause.
3683 Set_Used_Operations
(N
, New_Elmt_List
);
3684 Id
:= First
(Subtype_Marks
(N
));
3685 while Present
(Id
) loop
3689 if E
/= Any_Type
then
3692 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3693 if Nkind
(Id
) = N_Identifier
then
3694 Error_Msg_N
("type is not directly visible", Id
);
3696 elsif Is_Child_Unit
(Scope
(E
))
3697 and then Scope
(E
) /= System_Aux_Id
3699 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3704 -- If the use_type_clause appears in a compilation unit context,
3705 -- check whether it comes from a unit that may appear in a
3706 -- limited_with_clause, for a better error message.
3708 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3709 and then Nkind
(Id
) /= N_Identifier
3715 function Mentioned
(Nam
: Node_Id
) return Boolean;
3716 -- Check whether the prefix of expanded name for the type
3717 -- appears in the prefix of some limited_with_clause.
3723 function Mentioned
(Nam
: Node_Id
) return Boolean is
3725 return Nkind
(Name
(Item
)) = N_Selected_Component
3726 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3730 Pref
:= Prefix
(Id
);
3731 Item
:= First
(Context_Items
(Parent
(N
)));
3732 while Present
(Item
) and then Item
/= N
loop
3733 if Nkind
(Item
) = N_With_Clause
3734 and then Limited_Present
(Item
)
3735 and then Mentioned
(Pref
)
3738 (Get_Msg_Id
, "premature usage of incomplete type");
3749 end Analyze_Use_Type
;
3751 --------------------
3752 -- Applicable_Use --
3753 --------------------
3755 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3756 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3759 if In_Open_Scopes
(Pack
) then
3760 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3761 Error_Msg_NE
-- CODEFIX
3762 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3767 elsif In_Use
(Pack
) then
3768 Note_Redundant_Use
(Pack_Name
);
3771 elsif Present
(Renamed_Object
(Pack
))
3772 and then In_Use
(Renamed_Object
(Pack
))
3774 Note_Redundant_Use
(Pack_Name
);
3782 ------------------------
3783 -- Attribute_Renaming --
3784 ------------------------
3786 procedure Attribute_Renaming
(N
: Node_Id
) is
3787 Loc
: constant Source_Ptr
:= Sloc
(N
);
3788 Nam
: constant Node_Id
:= Name
(N
);
3789 Spec
: constant Node_Id
:= Specification
(N
);
3790 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3791 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3793 Form_Num
: Nat
:= 0;
3794 Expr_List
: List_Id
:= No_List
;
3796 Attr_Node
: Node_Id
;
3797 Body_Node
: Node_Id
;
3798 Param_Spec
: Node_Id
;
3801 Generate_Definition
(New_S
);
3803 -- This procedure is called in the context of subprogram renaming, and
3804 -- thus the attribute must be one that is a subprogram. All of those
3805 -- have at least one formal parameter, with the exceptions of the GNAT
3806 -- attribute 'Img, which GNAT treats as renameable.
3808 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3809 if Aname
/= Name_Img
then
3811 ("subprogram renaming an attribute must have formals", N
);
3816 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3817 while Present
(Param_Spec
) loop
3818 Form_Num
:= Form_Num
+ 1;
3820 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3821 Find_Type
(Parameter_Type
(Param_Spec
));
3823 -- The profile of the new entity denotes the base type (s) of
3824 -- the types given in the specification. For access parameters
3825 -- there are no subtypes involved.
3827 Rewrite
(Parameter_Type
(Param_Spec
),
3829 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3832 if No
(Expr_List
) then
3833 Expr_List
:= New_List
;
3836 Append_To
(Expr_List
,
3837 Make_Identifier
(Loc
,
3838 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3840 -- The expressions in the attribute reference are not freeze
3841 -- points. Neither is the attribute as a whole, see below.
3843 Set_Must_Not_Freeze
(Last
(Expr_List
));
3848 -- Immediate error if too many formals. Other mismatches in number or
3849 -- types of parameters are detected when we analyze the body of the
3850 -- subprogram that we construct.
3852 if Form_Num
> 2 then
3853 Error_Msg_N
("too many formals for attribute", N
);
3855 -- Error if the attribute reference has expressions that look like
3856 -- formal parameters.
3858 elsif Present
(Expressions
(Nam
)) then
3859 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3862 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3863 Name_Pos
, Name_Round
, Name_Scaling
,
3866 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3867 and then Present
(Corresponding_Formal_Spec
(N
))
3870 ("generic actual cannot be attribute involving universal type",
3874 ("attribute involving a universal type cannot be renamed",
3879 -- Rewrite attribute node to have a list of expressions corresponding to
3880 -- the subprogram formals. A renaming declaration is not a freeze point,
3881 -- and the analysis of the attribute reference should not freeze the
3882 -- type of the prefix. We use the original node in the renaming so that
3883 -- its source location is preserved, and checks on stream attributes are
3884 -- properly applied.
3886 Attr_Node
:= Relocate_Node
(Nam
);
3887 Set_Expressions
(Attr_Node
, Expr_List
);
3889 Set_Must_Not_Freeze
(Attr_Node
);
3890 Set_Must_Not_Freeze
(Prefix
(Nam
));
3892 -- Case of renaming a function
3894 if Nkind
(Spec
) = N_Function_Specification
then
3895 if Is_Procedure_Attribute_Name
(Aname
) then
3896 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3900 Find_Type
(Result_Definition
(Spec
));
3901 Rewrite
(Result_Definition
(Spec
),
3903 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3906 Make_Subprogram_Body
(Loc
,
3907 Specification
=> Spec
,
3908 Declarations
=> New_List
,
3909 Handled_Statement_Sequence
=>
3910 Make_Handled_Sequence_Of_Statements
(Loc
,
3911 Statements
=> New_List
(
3912 Make_Simple_Return_Statement
(Loc
,
3913 Expression
=> Attr_Node
))));
3915 -- Case of renaming a procedure
3918 if not Is_Procedure_Attribute_Name
(Aname
) then
3919 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3924 Make_Subprogram_Body
(Loc
,
3925 Specification
=> Spec
,
3926 Declarations
=> New_List
,
3927 Handled_Statement_Sequence
=>
3928 Make_Handled_Sequence_Of_Statements
(Loc
,
3929 Statements
=> New_List
(Attr_Node
)));
3932 -- In case of tagged types we add the body of the generated function to
3933 -- the freezing actions of the type (because in the general case such
3934 -- type is still not frozen). We exclude from this processing generic
3935 -- formal subprograms found in instantiations.
3937 -- We must exclude VM targets and restricted run-time libraries because
3938 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3939 -- available in those platforms. Note that we cannot use the function
3940 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3941 -- the ZFP run-time library is not defined as a profile, and we do not
3942 -- want to deal with AST_Handler in ZFP mode.
3944 if VM_Target
= No_VM
3945 and then not Configurable_Run_Time_Mode
3946 and then not Present
(Corresponding_Formal_Spec
(N
))
3947 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
3950 P
: constant Node_Id
:= Prefix
(Nam
);
3953 -- The prefix of 'Img is an object that is evaluated for each call
3954 -- of the function that renames it.
3956 if Aname
= Name_Img
then
3957 Preanalyze_And_Resolve
(P
);
3959 -- For all other attribute renamings, the prefix is a subtype
3965 -- If the target type is not yet frozen, add the body to the
3966 -- actions to be elaborated at freeze time.
3968 if Is_Tagged_Type
(Etype
(P
))
3969 and then In_Open_Scopes
(Scope
(Etype
(P
)))
3971 Ensure_Freeze_Node
(Etype
(P
));
3972 Append_Freeze_Action
(Etype
(P
), Body_Node
);
3974 Rewrite
(N
, Body_Node
);
3976 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3980 -- Generic formal subprograms or AST_Handler renaming
3983 Rewrite
(N
, Body_Node
);
3985 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3988 if Is_Compilation_Unit
(New_S
) then
3990 ("a library unit can only rename another library unit", N
);
3993 -- We suppress elaboration warnings for the resulting entity, since
3994 -- clearly they are not needed, and more particularly, in the case
3995 -- of a generic formal subprogram, the resulting entity can appear
3996 -- after the instantiation itself, and thus look like a bogus case
3997 -- of access before elaboration.
3999 Set_Suppress_Elaboration_Warnings
(New_S
);
4001 end Attribute_Renaming
;
4003 ----------------------
4004 -- Chain_Use_Clause --
4005 ----------------------
4007 procedure Chain_Use_Clause
(N
: Node_Id
) is
4009 Level
: Int
:= Scope_Stack
.Last
;
4012 if not Is_Compilation_Unit
(Current_Scope
)
4013 or else not Is_Child_Unit
(Current_Scope
)
4015 null; -- Common case
4017 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
4018 null; -- Common case for compilation unit
4021 -- If declaration appears in some other scope, it must be in some
4022 -- parent unit when compiling a child.
4024 Pack
:= Defining_Entity
(Parent
(N
));
4025 if not In_Open_Scopes
(Pack
) then
4026 null; -- default as well
4029 -- Find entry for parent unit in scope stack
4031 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4037 Set_Next_Use_Clause
(N
,
4038 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4039 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4040 end Chain_Use_Clause
;
4042 ---------------------------
4043 -- Check_Frozen_Renaming --
4044 ---------------------------
4046 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4051 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4054 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4056 if Is_Entity_Name
(Name
(N
)) then
4057 Old_S
:= Entity
(Name
(N
));
4059 if not Is_Frozen
(Old_S
)
4060 and then Operating_Mode
/= Check_Semantics
4062 Append_Freeze_Action
(Old_S
, B_Node
);
4064 Insert_After
(N
, B_Node
);
4068 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4070 ("subprogram used in renaming_as_body cannot be intrinsic",
4075 Insert_After
(N
, B_Node
);
4079 end Check_Frozen_Renaming
;
4081 -------------------------------
4082 -- Set_Entity_Or_Discriminal --
4083 -------------------------------
4085 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4089 -- If the entity is not a discriminant, or else expansion is disabled,
4090 -- simply set the entity.
4092 if not In_Spec_Expression
4093 or else Ekind
(E
) /= E_Discriminant
4094 or else Inside_A_Generic
4096 Set_Entity_With_Checks
(N
, E
);
4098 -- The replacement of a discriminant by the corresponding discriminal
4099 -- is not done for a task discriminant that appears in a default
4100 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4101 -- for details on their handling.
4103 elsif Is_Concurrent_Type
(Scope
(E
)) then
4106 and then not Nkind_In
(P
, N_Parameter_Specification
,
4107 N_Component_Declaration
)
4113 and then Nkind
(P
) = N_Parameter_Specification
4118 Set_Entity
(N
, Discriminal
(E
));
4121 -- Otherwise, this is a discriminant in a context in which
4122 -- it is a reference to the corresponding parameter of the
4123 -- init proc for the enclosing type.
4126 Set_Entity
(N
, Discriminal
(E
));
4128 end Set_Entity_Or_Discriminal
;
4130 -----------------------------------
4131 -- Check_In_Previous_With_Clause --
4132 -----------------------------------
4134 procedure Check_In_Previous_With_Clause
4138 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4143 Item
:= First
(Context_Items
(Parent
(N
)));
4144 while Present
(Item
) and then Item
/= N
loop
4145 if Nkind
(Item
) = N_With_Clause
4147 -- Protect the frontend against previous critical errors
4149 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4150 and then Entity
(Name
(Item
)) = Pack
4154 -- Find root library unit in with_clause
4156 while Nkind
(Par
) = N_Expanded_Name
loop
4157 Par
:= Prefix
(Par
);
4160 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4161 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4170 -- On exit, package is not mentioned in a previous with_clause.
4171 -- Check if its prefix is.
4173 if Nkind
(Nam
) = N_Expanded_Name
then
4174 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4176 elsif Pack
/= Any_Id
then
4177 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4179 end Check_In_Previous_With_Clause
;
4181 ---------------------------------
4182 -- Check_Library_Unit_Renaming --
4183 ---------------------------------
4185 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4189 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4192 -- Check for library unit. Note that we used to check for the scope
4193 -- being Standard here, but that was wrong for Standard itself.
4195 elsif not Is_Compilation_Unit
(Old_E
)
4196 and then not Is_Child_Unit
(Old_E
)
4198 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4200 -- Entities defined in Standard (operators and boolean literals) cannot
4201 -- be renamed as library units.
4203 elsif Scope
(Old_E
) = Standard_Standard
4204 and then Sloc
(Old_E
) = Standard_Location
4206 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4208 elsif Present
(Parent_Spec
(N
))
4209 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4210 and then not Is_Child_Unit
(Old_E
)
4213 ("renamed unit must be a child unit of generic parent", Name
(N
));
4215 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4216 and then Nkind
(Name
(N
)) = N_Expanded_Name
4217 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4218 and then Is_Generic_Unit
(Old_E
)
4221 ("renamed generic unit must be a library unit", Name
(N
));
4223 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4225 -- Inherit categorization flags
4227 New_E
:= Defining_Entity
(N
);
4228 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4229 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4230 Set_Is_Remote_Call_Interface
(New_E
,
4231 Is_Remote_Call_Interface
(Old_E
));
4232 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4233 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4235 end Check_Library_Unit_Renaming
;
4237 ------------------------
4238 -- Enclosing_Instance --
4239 ------------------------
4241 function Enclosing_Instance
return Entity_Id
is
4245 if not Is_Generic_Instance
(Current_Scope
) then
4249 S
:= Scope
(Current_Scope
);
4250 while S
/= Standard_Standard
loop
4251 if Is_Generic_Instance
(S
) then
4259 end Enclosing_Instance
;
4265 procedure End_Scope
is
4271 Id
:= First_Entity
(Current_Scope
);
4272 while Present
(Id
) loop
4273 -- An entity in the current scope is not necessarily the first one
4274 -- on its homonym chain. Find its predecessor if any,
4275 -- If it is an internal entity, it will not be in the visibility
4276 -- chain altogether, and there is nothing to unchain.
4278 if Id
/= Current_Entity
(Id
) then
4279 Prev
:= Current_Entity
(Id
);
4280 while Present
(Prev
)
4281 and then Present
(Homonym
(Prev
))
4282 and then Homonym
(Prev
) /= Id
4284 Prev
:= Homonym
(Prev
);
4287 -- Skip to end of loop if Id is not in the visibility chain
4289 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4297 Set_Is_Immediately_Visible
(Id
, False);
4299 Outer
:= Homonym
(Id
);
4300 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4301 Outer
:= Homonym
(Outer
);
4304 -- Reset homonym link of other entities, but do not modify link
4305 -- between entities in current scope, so that the back-end can have
4306 -- a proper count of local overloadings.
4309 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4311 elsif Scope
(Prev
) /= Scope
(Id
) then
4312 Set_Homonym
(Prev
, Outer
);
4319 -- If the scope generated freeze actions, place them before the
4320 -- current declaration and analyze them. Type declarations and
4321 -- the bodies of initialization procedures can generate such nodes.
4322 -- We follow the parent chain until we reach a list node, which is
4323 -- the enclosing list of declarations. If the list appears within
4324 -- a protected definition, move freeze nodes outside the protected
4328 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4332 L
: constant List_Id
:= Scope_Stack
.Table
4333 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4336 if Is_Itype
(Current_Scope
) then
4337 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4339 Decl
:= Parent
(Current_Scope
);
4344 while not (Is_List_Member
(Decl
))
4345 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4348 Decl
:= Parent
(Decl
);
4351 Insert_List_Before_And_Analyze
(Decl
, L
);
4359 ---------------------
4360 -- End_Use_Clauses --
4361 ---------------------
4363 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4367 -- Remove Use_Type clauses first, because they affect the
4368 -- visibility of operators in subsequent used packages.
4371 while Present
(U
) loop
4372 if Nkind
(U
) = N_Use_Type_Clause
then
4376 Next_Use_Clause
(U
);
4380 while Present
(U
) loop
4381 if Nkind
(U
) = N_Use_Package_Clause
then
4382 End_Use_Package
(U
);
4385 Next_Use_Clause
(U
);
4387 end End_Use_Clauses
;
4389 ---------------------
4390 -- End_Use_Package --
4391 ---------------------
4393 procedure End_Use_Package
(N
: Node_Id
) is
4394 Pack_Name
: Node_Id
;
4399 function Is_Primitive_Operator_In_Use
4401 F
: Entity_Id
) return Boolean;
4402 -- Check whether Op is a primitive operator of a use-visible type
4404 ----------------------------------
4405 -- Is_Primitive_Operator_In_Use --
4406 ----------------------------------
4408 function Is_Primitive_Operator_In_Use
4410 F
: Entity_Id
) return Boolean
4412 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4414 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4415 end Is_Primitive_Operator_In_Use
;
4417 -- Start of processing for End_Use_Package
4420 Pack_Name
:= First
(Names
(N
));
4421 while Present
(Pack_Name
) loop
4423 -- Test that Pack_Name actually denotes a package before processing
4425 if Is_Entity_Name
(Pack_Name
)
4426 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4428 Pack
:= Entity
(Pack_Name
);
4430 if In_Open_Scopes
(Pack
) then
4433 elsif not Redundant_Use
(Pack_Name
) then
4434 Set_In_Use
(Pack
, False);
4435 Set_Current_Use_Clause
(Pack
, Empty
);
4437 Id
:= First_Entity
(Pack
);
4438 while Present
(Id
) loop
4440 -- Preserve use-visibility of operators that are primitive
4441 -- operators of a type that is use-visible through an active
4444 if Nkind
(Id
) = N_Defining_Operator_Symbol
4446 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4448 (Present
(Next_Formal
(First_Formal
(Id
)))
4450 Is_Primitive_Operator_In_Use
4451 (Id
, Next_Formal
(First_Formal
(Id
)))))
4455 Set_Is_Potentially_Use_Visible
(Id
, False);
4458 if Is_Private_Type
(Id
)
4459 and then Present
(Full_View
(Id
))
4461 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4467 if Present
(Renamed_Object
(Pack
)) then
4468 Set_In_Use
(Renamed_Object
(Pack
), False);
4469 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4472 if Chars
(Pack
) = Name_System
4473 and then Scope
(Pack
) = Standard_Standard
4474 and then Present_System_Aux
4476 Id
:= First_Entity
(System_Aux_Id
);
4477 while Present
(Id
) loop
4478 Set_Is_Potentially_Use_Visible
(Id
, False);
4480 if Is_Private_Type
(Id
)
4481 and then Present
(Full_View
(Id
))
4483 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4489 Set_In_Use
(System_Aux_Id
, False);
4493 Set_Redundant_Use
(Pack_Name
, False);
4500 if Present
(Hidden_By_Use_Clause
(N
)) then
4501 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4502 while Present
(Elmt
) loop
4504 E
: constant Entity_Id
:= Node
(Elmt
);
4507 -- Reset either Use_Visibility or Direct_Visibility, depending
4508 -- on how the entity was hidden by the use clause.
4510 if In_Use
(Scope
(E
))
4511 and then Used_As_Generic_Actual
(Scope
(E
))
4513 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4515 Set_Is_Immediately_Visible
(Node
(Elmt
));
4522 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4524 end End_Use_Package
;
4530 procedure End_Use_Type
(N
: Node_Id
) is
4535 -- Start of processing for End_Use_Type
4538 Id
:= First
(Subtype_Marks
(N
));
4539 while Present
(Id
) loop
4541 -- A call to Rtsfind may occur while analyzing a use_type clause,
4542 -- in which case the type marks are not resolved yet, and there is
4543 -- nothing to remove.
4545 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4551 if T
= Any_Type
or else From_Limited_With
(T
) then
4554 -- Note that the use_type clause may mention a subtype of the type
4555 -- whose primitive operations have been made visible. Here as
4556 -- elsewhere, it is the base type that matters for visibility.
4558 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4561 elsif not Redundant_Use
(Id
) then
4562 Set_In_Use
(T
, False);
4563 Set_In_Use
(Base_Type
(T
), False);
4564 Set_Current_Use_Clause
(T
, Empty
);
4565 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4572 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4576 Elmt
:= First_Elmt
(Used_Operations
(N
));
4577 while Present
(Elmt
) loop
4578 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4584 ----------------------
4585 -- Find_Direct_Name --
4586 ----------------------
4588 procedure Find_Direct_Name
(N
: Node_Id
) is
4593 Inst
: Entity_Id
:= Empty
;
4594 -- Enclosing instance, if any
4596 Homonyms
: Entity_Id
;
4597 -- Saves start of homonym chain
4599 Nvis_Entity
: Boolean;
4600 -- Set True to indicate that there is at least one entity on the homonym
4601 -- chain which, while not visible, is visible enough from the user point
4602 -- of view to warrant an error message of "not visible" rather than
4605 Nvis_Is_Private_Subprg
: Boolean := False;
4606 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4607 -- effect concerning library subprograms has been detected. Used to
4608 -- generate the precise error message.
4610 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4611 -- Returns true if the entity is an actual for a package that is itself
4612 -- an actual for a formal package of the current instance. Such an
4613 -- entity requires special handling because it may be use-visible but
4614 -- hides directly visible entities defined outside the instance, because
4615 -- the corresponding formal did so in the generic.
4617 function Is_Actual_Parameter
return Boolean;
4618 -- This function checks if the node N is an identifier that is an actual
4619 -- parameter of a procedure call. If so it returns True, otherwise it
4620 -- return False. The reason for this check is that at this stage we do
4621 -- not know what procedure is being called if the procedure might be
4622 -- overloaded, so it is premature to go setting referenced flags or
4623 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4624 -- for that processing
4626 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4627 -- This function determines whether a reference to the entity E, which
4628 -- is not visible, can reasonably be considered to be known to the
4629 -- writer of the reference. This is a heuristic test, used only for
4630 -- the purposes of figuring out whether we prefer to complain that an
4631 -- entity is undefined or invisible (and identify the declaration of
4632 -- the invisible entity in the latter case). The point here is that we
4633 -- don't want to complain that something is invisible and then point to
4634 -- something entirely mysterious to the writer.
4636 procedure Nvis_Messages
;
4637 -- Called if there are no visible entries for N, but there is at least
4638 -- one non-directly visible, or hidden declaration. This procedure
4639 -- outputs an appropriate set of error messages.
4641 procedure Undefined
(Nvis
: Boolean);
4642 -- This function is called if the current node has no corresponding
4643 -- visible entity or entities. The value set in Msg indicates whether
4644 -- an error message was generated (multiple error messages for the
4645 -- same variable are generally suppressed, see body for details).
4646 -- Msg is True if an error message was generated, False if not. This
4647 -- value is used by the caller to determine whether or not to output
4648 -- additional messages where appropriate. The parameter is set False
4649 -- to get the message "X is undefined", and True to get the message
4650 -- "X is not visible".
4652 -------------------------
4653 -- From_Actual_Package --
4654 -------------------------
4656 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4657 Scop
: constant Entity_Id
:= Scope
(E
);
4658 -- Declared scope of candidate entity
4662 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4663 -- Recursive function that does the work and examines actuals of
4664 -- actual packages of current instance.
4666 ------------------------
4667 -- Declared_In_Actual --
4668 ------------------------
4670 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4674 if No
(Associated_Formal_Package
(Pack
)) then
4678 Act
:= First_Entity
(Pack
);
4679 while Present
(Act
) loop
4680 if Renamed_Object
(Pack
) = Scop
then
4683 -- Check for end of list of actuals.
4685 elsif Ekind
(Act
) = E_Package
4686 and then Renamed_Object
(Act
) = Pack
4690 elsif Ekind
(Act
) = E_Package
4691 and then Declared_In_Actual
(Act
)
4701 end Declared_In_Actual
;
4703 -- Start of processing for From_Actual_Package
4706 if not In_Instance
then
4710 Inst
:= Current_Scope
;
4711 while Present
(Inst
)
4712 and then Ekind
(Inst
) /= E_Package
4713 and then not Is_Generic_Instance
(Inst
)
4715 Inst
:= Scope
(Inst
);
4722 Act
:= First_Entity
(Inst
);
4723 while Present
(Act
) loop
4724 if Ekind
(Act
) = E_Package
4725 and then Declared_In_Actual
(Act
)
4735 end From_Actual_Package
;
4737 -------------------------
4738 -- Is_Actual_Parameter --
4739 -------------------------
4741 function Is_Actual_Parameter
return Boolean is
4744 Nkind
(N
) = N_Identifier
4746 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4748 (Nkind
(Parent
(N
)) = N_Parameter_Association
4749 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4750 and then Nkind
(Parent
(Parent
(N
))) =
4751 N_Procedure_Call_Statement
));
4752 end Is_Actual_Parameter
;
4754 -------------------------
4755 -- Known_But_Invisible --
4756 -------------------------
4758 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4759 Fname
: File_Name_Type
;
4762 -- Entities in Standard are always considered to be known
4764 if Sloc
(E
) <= Standard_Location
then
4767 -- An entity that does not come from source is always considered
4768 -- to be unknown, since it is an artifact of code expansion.
4770 elsif not Comes_From_Source
(E
) then
4773 -- In gnat internal mode, we consider all entities known. The
4774 -- historical reason behind this discrepancy is not known??? But the
4775 -- only effect is to modify the error message given, so it is not
4776 -- critical. Since it only affects the exact wording of error
4777 -- messages in illegal programs, we do not mention this as an
4778 -- effect of -gnatg, since it is not a language modification.
4780 elsif GNAT_Mode
then
4784 -- Here we have an entity that is not from package Standard, and
4785 -- which comes from Source. See if it comes from an internal file.
4787 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4789 -- Case of from internal file
4791 if Is_Internal_File_Name
(Fname
) then
4793 -- Private part entities in internal files are never considered
4794 -- to be known to the writer of normal application code.
4796 if Is_Hidden
(E
) then
4800 -- Entities from System packages other than System and
4801 -- System.Storage_Elements are not considered to be known.
4802 -- System.Auxxxx files are also considered known to the user.
4804 -- Should refine this at some point to generally distinguish
4805 -- between known and unknown internal files ???
4807 Get_Name_String
(Fname
);
4812 Name_Buffer
(1 .. 2) /= "s-"
4814 Name_Buffer
(3 .. 8) = "stoele"
4816 Name_Buffer
(3 .. 5) = "aux";
4818 -- If not an internal file, then entity is definitely known,
4819 -- even if it is in a private part (the message generated will
4820 -- note that it is in a private part)
4825 end Known_But_Invisible
;
4831 procedure Nvis_Messages
is
4832 Comp_Unit
: Node_Id
;
4834 Found
: Boolean := False;
4835 Hidden
: Boolean := False;
4839 -- Ada 2005 (AI-262): Generate a precise error concerning the
4840 -- Beaujolais effect that was previously detected
4842 if Nvis_Is_Private_Subprg
then
4844 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4845 and then Ekind
(E2
) = E_Function
4846 and then Scope
(E2
) = Standard_Standard
4847 and then Has_Private_With
(E2
));
4849 -- Find the sloc corresponding to the private with'ed unit
4851 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4852 Error_Msg_Sloc
:= No_Location
;
4854 Item
:= First
(Context_Items
(Comp_Unit
));
4855 while Present
(Item
) loop
4856 if Nkind
(Item
) = N_With_Clause
4857 and then Private_Present
(Item
)
4858 and then Entity
(Name
(Item
)) = E2
4860 Error_Msg_Sloc
:= Sloc
(Item
);
4867 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4869 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4873 Undefined
(Nvis
=> True);
4877 -- First loop does hidden declarations
4880 while Present
(Ent
) loop
4881 if Is_Potentially_Use_Visible
(Ent
) then
4883 Error_Msg_N
-- CODEFIX
4884 ("multiple use clauses cause hiding!", N
);
4888 Error_Msg_Sloc
:= Sloc
(Ent
);
4889 Error_Msg_N
-- CODEFIX
4890 ("hidden declaration#!", N
);
4893 Ent
:= Homonym
(Ent
);
4896 -- If we found hidden declarations, then that's enough, don't
4897 -- bother looking for non-visible declarations as well.
4903 -- Second loop does non-directly visible declarations
4906 while Present
(Ent
) loop
4907 if not Is_Potentially_Use_Visible
(Ent
) then
4909 -- Do not bother the user with unknown entities
4911 if not Known_But_Invisible
(Ent
) then
4915 Error_Msg_Sloc
:= Sloc
(Ent
);
4917 -- Output message noting that there is a non-visible
4918 -- declaration, distinguishing the private part case.
4920 if Is_Hidden
(Ent
) then
4921 Error_Msg_N
("non-visible (private) declaration#!", N
);
4923 -- If the entity is declared in a generic package, it
4924 -- cannot be visible, so there is no point in adding it
4925 -- to the list of candidates if another homograph from a
4926 -- non-generic package has been seen.
4928 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4934 Error_Msg_N
-- CODEFIX
4935 ("non-visible declaration#!", N
);
4937 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
4941 if Is_Compilation_Unit
(Ent
)
4943 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
4945 Error_Msg_Qual_Level
:= 99;
4946 Error_Msg_NE
-- CODEFIX
4947 ("\\missing `WITH &;`", N
, Ent
);
4948 Error_Msg_Qual_Level
:= 0;
4951 if Ekind
(Ent
) = E_Discriminant
4952 and then Present
(Corresponding_Discriminant
(Ent
))
4953 and then Scope
(Corresponding_Discriminant
(Ent
)) =
4957 ("inherited discriminant not allowed here" &
4958 " (RM 3.8 (12), 3.8.1 (6))!", N
);
4962 -- Set entity and its containing package as referenced. We
4963 -- can't be sure of this, but this seems a better choice
4964 -- to avoid unused entity messages.
4966 if Comes_From_Source
(Ent
) then
4967 Set_Referenced
(Ent
);
4968 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
4973 Ent
:= Homonym
(Ent
);
4982 procedure Undefined
(Nvis
: Boolean) is
4983 Emsg
: Error_Msg_Id
;
4986 -- We should never find an undefined internal name. If we do, then
4987 -- see if we have previous errors. If so, ignore on the grounds that
4988 -- it is probably a cascaded message (e.g. a block label from a badly
4989 -- formed block). If no previous errors, then we have a real internal
4990 -- error of some kind so raise an exception.
4992 if Is_Internal_Name
(Chars
(N
)) then
4993 if Total_Errors_Detected
/= 0 then
4996 raise Program_Error
;
5000 -- A very specialized error check, if the undefined variable is
5001 -- a case tag, and the case type is an enumeration type, check
5002 -- for a possible misspelling, and if so, modify the identifier
5004 -- Named aggregate should also be handled similarly ???
5006 if Nkind
(N
) = N_Identifier
5007 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5010 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5011 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5016 if Is_Enumeration_Type
(Case_Typ
)
5017 and then not Is_Standard_Character_Type
(Case_Typ
)
5019 Lit
:= First_Literal
(Case_Typ
);
5020 Get_Name_String
(Chars
(Lit
));
5022 if Chars
(Lit
) /= Chars
(N
)
5023 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5025 Error_Msg_Node_2
:= Lit
;
5026 Error_Msg_N
-- CODEFIX
5027 ("& is undefined, assume misspelling of &", N
);
5028 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5032 Lit
:= Next_Literal
(Lit
);
5037 -- Normal processing
5039 Set_Entity
(N
, Any_Id
);
5040 Set_Etype
(N
, Any_Type
);
5042 -- We use the table Urefs to keep track of entities for which we
5043 -- have issued errors for undefined references. Multiple errors
5044 -- for a single name are normally suppressed, however we modify
5045 -- the error message to alert the programmer to this effect.
5047 for J
in Urefs
.First
.. Urefs
.Last
loop
5048 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5049 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5050 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5052 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5054 if Urefs
.Table
(J
).Nvis
then
5055 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5056 "& is not visible (more references follow)");
5058 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5059 "& is undefined (more references follow)");
5062 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5065 -- Although we will set Msg False, and thus suppress the
5066 -- message, we also set Error_Posted True, to avoid any
5067 -- cascaded messages resulting from the undefined reference.
5070 Set_Error_Posted
(N
, True);
5075 -- If entry not found, this is first undefined occurrence
5078 Error_Msg_N
("& is not visible!", N
);
5082 Error_Msg_N
("& is undefined!", N
);
5085 -- A very bizarre special check, if the undefined identifier
5086 -- is put or put_line, then add a special error message (since
5087 -- this is a very common error for beginners to make).
5089 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5090 Error_Msg_N
-- CODEFIX
5091 ("\\possible missing `WITH Ada.Text_'I'O; " &
5092 "USE Ada.Text_'I'O`!", N
);
5094 -- Another special check if N is the prefix of a selected
5095 -- component which is a known unit, add message complaining
5096 -- about missing with for this unit.
5098 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5099 and then N
= Prefix
(Parent
(N
))
5100 and then Is_Known_Unit
(Parent
(N
))
5102 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5103 Error_Msg_N
-- CODEFIX
5104 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5107 -- Now check for possible misspellings
5111 Ematch
: Entity_Id
:= Empty
;
5113 Last_Name_Id
: constant Name_Id
:=
5114 Name_Id
(Nat
(First_Name_Id
) +
5115 Name_Entries_Count
- 1);
5118 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5119 E
:= Get_Name_Entity_Id
(Nam
);
5122 and then (Is_Immediately_Visible
(E
)
5124 Is_Potentially_Use_Visible
(E
))
5126 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5133 if Present
(Ematch
) then
5134 Error_Msg_NE
-- CODEFIX
5135 ("\possible misspelling of&", N
, Ematch
);
5140 -- Make entry in undefined references table unless the full errors
5141 -- switch is set, in which case by refraining from generating the
5142 -- table entry, we guarantee that we get an error message for every
5143 -- undefined reference.
5145 if not All_Errors_Mode
then
5156 -- Start of processing for Find_Direct_Name
5159 -- If the entity pointer is already set, this is an internal node, or
5160 -- a node that is analyzed more than once, after a tree modification.
5161 -- In such a case there is no resolution to perform, just set the type.
5163 if Present
(Entity
(N
)) then
5164 if Is_Type
(Entity
(N
)) then
5165 Set_Etype
(N
, Entity
(N
));
5169 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5172 -- One special case here. If the Etype field is already set,
5173 -- and references the packed array type corresponding to the
5174 -- etype of the referenced entity, then leave it alone. This
5175 -- happens for trees generated from Exp_Pakd, where expressions
5176 -- can be deliberately "mis-typed" to the packed array type.
5178 if Is_Array_Type
(Entyp
)
5179 and then Is_Packed
(Entyp
)
5180 and then Present
(Etype
(N
))
5181 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5185 -- If not that special case, then just reset the Etype
5188 Set_Etype
(N
, Etype
(Entity
(N
)));
5196 -- Here if Entity pointer was not set, we need full visibility analysis
5197 -- First we generate debugging output if the debug E flag is set.
5199 if Debug_Flag_E
then
5200 Write_Str
("Looking for ");
5201 Write_Name
(Chars
(N
));
5205 Homonyms
:= Current_Entity
(N
);
5206 Nvis_Entity
:= False;
5209 while Present
(E
) loop
5211 -- If entity is immediately visible or potentially use visible, then
5212 -- process the entity and we are done.
5214 if Is_Immediately_Visible
(E
) then
5215 goto Immediately_Visible_Entity
;
5217 elsif Is_Potentially_Use_Visible
(E
) then
5218 goto Potentially_Use_Visible_Entity
;
5220 -- Note if a known but invisible entity encountered
5222 elsif Known_But_Invisible
(E
) then
5223 Nvis_Entity
:= True;
5226 -- Move to next entity in chain and continue search
5231 -- If no entries on homonym chain that were potentially visible,
5232 -- and no entities reasonably considered as non-visible, then
5233 -- we have a plain undefined reference, with no additional
5234 -- explanation required.
5236 if not Nvis_Entity
then
5237 Undefined
(Nvis
=> False);
5239 -- Otherwise there is at least one entry on the homonym chain that
5240 -- is reasonably considered as being known and non-visible.
5248 -- Processing for a potentially use visible entry found. We must search
5249 -- the rest of the homonym chain for two reasons. First, if there is a
5250 -- directly visible entry, then none of the potentially use-visible
5251 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5252 -- for the case of multiple potentially use-visible entries hiding one
5253 -- another and as a result being non-directly visible (RM 8.4(11)).
5255 <<Potentially_Use_Visible_Entity
>> declare
5256 Only_One_Visible
: Boolean := True;
5257 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5261 while Present
(E2
) loop
5262 if Is_Immediately_Visible
(E2
) then
5264 -- If the use-visible entity comes from the actual for a
5265 -- formal package, it hides a directly visible entity from
5266 -- outside the instance.
5268 if From_Actual_Package
(E
)
5269 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5274 goto Immediately_Visible_Entity
;
5277 elsif Is_Potentially_Use_Visible
(E2
) then
5278 Only_One_Visible
:= False;
5279 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5281 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5282 -- that can occur in private_with clauses. Example:
5285 -- private with B; package A is
5286 -- package C is function B return Integer;
5288 -- V1 : Integer := B;
5289 -- private function B return Integer;
5290 -- V2 : Integer := B;
5293 -- V1 resolves to A.B, but V2 resolves to library unit B
5295 elsif Ekind
(E2
) = E_Function
5296 and then Scope
(E2
) = Standard_Standard
5297 and then Has_Private_With
(E2
)
5299 Only_One_Visible
:= False;
5300 All_Overloadable
:= False;
5301 Nvis_Is_Private_Subprg
:= True;
5308 -- On falling through this loop, we have checked that there are no
5309 -- immediately visible entities. Only_One_Visible is set if exactly
5310 -- one potentially use visible entity exists. All_Overloadable is
5311 -- set if all the potentially use visible entities are overloadable.
5312 -- The condition for legality is that either there is one potentially
5313 -- use visible entity, or if there is more than one, then all of them
5314 -- are overloadable.
5316 if Only_One_Visible
or All_Overloadable
then
5319 -- If there is more than one potentially use-visible entity and at
5320 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5321 -- Note that E points to the first such entity on the homonym list.
5322 -- Special case: if one of the entities is declared in an actual
5323 -- package, it was visible in the generic, and takes precedence over
5324 -- other entities that are potentially use-visible. Same if it is
5325 -- declared in a local instantiation of the current instance.
5330 -- Find current instance
5332 Inst
:= Current_Scope
;
5333 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5334 if Is_Generic_Instance
(Inst
) then
5338 Inst
:= Scope
(Inst
);
5342 while Present
(E2
) loop
5343 if From_Actual_Package
(E2
)
5345 (Is_Generic_Instance
(Scope
(E2
))
5346 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5359 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5361 -- A use-clause in the body of a system file creates conflict
5362 -- with some entity in a user scope, while rtsfind is active.
5363 -- Keep only the entity coming from another predefined unit.
5366 while Present
(E2
) loop
5367 if Is_Predefined_File_Name
5368 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5377 -- Entity must exist because predefined unit is correct
5379 raise Program_Error
;
5388 -- Come here with E set to the first immediately visible entity on
5389 -- the homonym chain. This is the one we want unless there is another
5390 -- immediately visible entity further on in the chain for an inner
5391 -- scope (RM 8.3(8)).
5393 <<Immediately_Visible_Entity
>> declare
5398 -- Find scope level of initial entity. When compiling through
5399 -- Rtsfind, the previous context is not completely invisible, and
5400 -- an outer entity may appear on the chain, whose scope is below
5401 -- the entry for Standard that delimits the current scope stack.
5402 -- Indicate that the level for this spurious entry is outside of
5403 -- the current scope stack.
5405 Level
:= Scope_Stack
.Last
;
5407 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5408 exit when Scop
= Scope
(E
);
5410 exit when Scop
= Standard_Standard
;
5413 -- Now search remainder of homonym chain for more inner entry
5414 -- If the entity is Standard itself, it has no scope, and we
5415 -- compare it with the stack entry directly.
5418 while Present
(E2
) loop
5419 if Is_Immediately_Visible
(E2
) then
5421 -- If a generic package contains a local declaration that
5422 -- has the same name as the generic, there may be a visibility
5423 -- conflict in an instance, where the local declaration must
5424 -- also hide the name of the corresponding package renaming.
5425 -- We check explicitly for a package declared by a renaming,
5426 -- whose renamed entity is an instance that is on the scope
5427 -- stack, and that contains a homonym in the same scope. Once
5428 -- we have found it, we know that the package renaming is not
5429 -- immediately visible, and that the identifier denotes the
5430 -- other entity (and its homonyms if overloaded).
5432 if Scope
(E
) = Scope
(E2
)
5433 and then Ekind
(E
) = E_Package
5434 and then Present
(Renamed_Object
(E
))
5435 and then Is_Generic_Instance
(Renamed_Object
(E
))
5436 and then In_Open_Scopes
(Renamed_Object
(E
))
5437 and then Comes_From_Source
(N
)
5439 Set_Is_Immediately_Visible
(E
, False);
5443 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5444 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5445 or else Scope_Stack
.Table
(J
).Entity
= E2
5458 -- At the end of that loop, E is the innermost immediately
5459 -- visible entity, so we are all set.
5462 -- Come here with entity found, and stored in E
5466 -- Check violation of No_Wide_Characters restriction
5468 Check_Wide_Character_Restriction
(E
, N
);
5470 -- When distribution features are available (Get_PCS_Name /=
5471 -- Name_No_DSA), a remote access-to-subprogram type is converted
5472 -- into a record type holding whatever information is needed to
5473 -- perform a remote call on an RCI subprogram. In that case we
5474 -- rewrite any occurrence of the RAS type into the equivalent record
5475 -- type here. 'Access attribute references and RAS dereferences are
5476 -- then implemented using specific TSSs. However when distribution is
5477 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5478 -- generation of these TSSs, and we must keep the RAS type in its
5479 -- original access-to-subprogram form (since all calls through a
5480 -- value of such type will be local anyway in the absence of a PCS).
5482 if Comes_From_Source
(N
)
5483 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5484 and then Ekind
(E
) = E_Access_Subprogram_Type
5485 and then Expander_Active
5486 and then Get_PCS_Name
/= Name_No_DSA
5488 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5492 -- Set the entity. Note that the reason we call Set_Entity for the
5493 -- overloadable case, as opposed to Set_Entity_With_Checks is
5494 -- that in the overloaded case, the initial call can set the wrong
5495 -- homonym. The call that sets the right homonym is in Sem_Res and
5496 -- that call does use Set_Entity_With_Checks, so we don't miss
5499 if Is_Overloadable
(E
) then
5502 Set_Entity_With_Checks
(N
, E
);
5508 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5511 if Debug_Flag_E
then
5512 Write_Str
(" found ");
5513 Write_Entity_Info
(E
, " ");
5516 -- If the Ekind of the entity is Void, it means that all homonyms
5517 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5518 -- test is skipped if the current scope is a record and the name is
5519 -- a pragma argument expression (case of Atomic and Volatile pragmas
5520 -- and possibly other similar pragmas added later, which are allowed
5521 -- to reference components in the current record).
5523 if Ekind
(E
) = E_Void
5525 (not Is_Record_Type
(Current_Scope
)
5526 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5528 Premature_Usage
(N
);
5530 -- If the entity is overloadable, collect all interpretations of the
5531 -- name for subsequent overload resolution. We optimize a bit here to
5532 -- do this only if we have an overloadable entity that is not on its
5533 -- own on the homonym chain.
5535 elsif Is_Overloadable
(E
)
5536 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5538 Collect_Interps
(N
);
5540 -- If no homonyms were visible, the entity is unambiguous
5542 if not Is_Overloaded
(N
) then
5543 if not Is_Actual_Parameter
then
5544 Generate_Reference
(E
, N
);
5548 -- Case of non-overloadable entity, set the entity providing that
5549 -- we do not have the case of a discriminant reference within a
5550 -- default expression. Such references are replaced with the
5551 -- corresponding discriminal, which is the formal corresponding to
5552 -- to the discriminant in the initialization procedure.
5555 -- Entity is unambiguous, indicate that it is referenced here
5557 -- For a renaming of an object, always generate simple reference,
5558 -- we don't try to keep track of assignments in this case, except
5559 -- in SPARK mode where renamings are traversed for generating
5560 -- local effects of subprograms.
5563 and then Present
(Renamed_Object
(E
))
5564 and then not GNATprove_Mode
5566 Generate_Reference
(E
, N
);
5568 -- If the renamed entity is a private protected component,
5569 -- reference the original component as well. This needs to be
5570 -- done because the private renamings are installed before any
5571 -- analysis has occurred. Reference to a private component will
5572 -- resolve to the renaming and the original component will be
5573 -- left unreferenced, hence the following.
5575 if Is_Prival
(E
) then
5576 Generate_Reference
(Prival_Link
(E
), N
);
5579 -- One odd case is that we do not want to set the Referenced flag
5580 -- if the entity is a label, and the identifier is the label in
5581 -- the source, since this is not a reference from the point of
5582 -- view of the user.
5584 elsif Nkind
(Parent
(N
)) = N_Label
then
5586 R
: constant Boolean := Referenced
(E
);
5589 -- Generate reference unless this is an actual parameter
5590 -- (see comment below)
5592 if Is_Actual_Parameter
then
5593 Generate_Reference
(E
, N
);
5594 Set_Referenced
(E
, R
);
5598 -- Normal case, not a label: generate reference
5601 if not Is_Actual_Parameter
then
5603 -- Package or generic package is always a simple reference
5605 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5606 Generate_Reference
(E
, N
, 'r');
5608 -- Else see if we have a left hand side
5613 Generate_Reference
(E
, N
, 'm');
5616 Generate_Reference
(E
, N
, 'r');
5618 -- If we don't know now, generate reference later
5621 Deferred_References
.Append
((E
, N
));
5626 Check_Nested_Access
(N
, E
);
5629 Set_Entity_Or_Discriminal
(N
, E
);
5631 -- The name may designate a generalized reference, in which case
5632 -- the dereference interpretation will be included.
5634 if Ada_Version
>= Ada_2012
5636 (Nkind
(Parent
(N
)) in N_Subexpr
5637 or else Nkind_In
(Parent
(N
), N_Object_Declaration
,
5638 N_Assignment_Statement
))
5640 Check_Implicit_Dereference
(N
, Etype
(E
));
5645 -- Come here with entity set
5648 Check_Restriction_No_Use_Of_Entity
(N
);
5649 end Find_Direct_Name
;
5651 ------------------------
5652 -- Find_Expanded_Name --
5653 ------------------------
5655 -- This routine searches the homonym chain of the entity until it finds
5656 -- an entity declared in the scope denoted by the prefix. If the entity
5657 -- is private, it may nevertheless be immediately visible, if we are in
5658 -- the scope of its declaration.
5660 procedure Find_Expanded_Name
(N
: Node_Id
) is
5661 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean;
5662 -- Determine whether an arbitrary node N appears in pragmas [Refined_]
5663 -- Depends or [Refined_]Global.
5665 ----------------------------------
5666 -- In_Pragmas_Depends_Or_Global --
5667 ----------------------------------
5669 function In_Pragmas_Depends_Or_Global
(N
: Node_Id
) return Boolean is
5673 -- Climb the parent chain looking for a pragma
5676 while Present
(Par
) loop
5677 if Nkind
(Par
) = N_Pragma
5678 and then Nam_In
(Pragma_Name
(Par
), Name_Depends
,
5680 Name_Refined_Depends
,
5681 Name_Refined_Global
)
5685 -- Prevent the search from going too far
5687 elsif Is_Body_Or_Package_Declaration
(Par
) then
5691 Par
:= Parent
(Par
);
5695 end In_Pragmas_Depends_Or_Global
;
5699 Selector
: constant Node_Id
:= Selector_Name
(N
);
5700 Candidate
: Entity_Id
:= Empty
;
5704 -- Start of processing for Find_Expanded_Name
5707 P_Name
:= Entity
(Prefix
(N
));
5709 -- If the prefix is a renamed package, look for the entity in the
5710 -- original package.
5712 if Ekind
(P_Name
) = E_Package
5713 and then Present
(Renamed_Object
(P_Name
))
5715 P_Name
:= Renamed_Object
(P_Name
);
5717 -- Rewrite node with entity field pointing to renamed object
5719 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5720 Set_Entity
(Prefix
(N
), P_Name
);
5722 -- If the prefix is an object of a concurrent type, look for
5723 -- the entity in the associated task or protected type.
5725 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5726 P_Name
:= Etype
(P_Name
);
5729 Id
:= Current_Entity
(Selector
);
5732 Is_New_Candidate
: Boolean;
5735 while Present
(Id
) loop
5736 if Scope
(Id
) = P_Name
then
5738 Is_New_Candidate
:= True;
5740 -- Handle abstract views of states and variables. These are
5741 -- acceptable only when the reference to the view appears in
5742 -- pragmas [Refined_]Depends and [Refined_]Global.
5744 if Ekind
(Id
) = E_Abstract_State
5745 and then From_Limited_With
(Id
)
5746 and then Present
(Non_Limited_View
(Id
))
5748 if In_Pragmas_Depends_Or_Global
(N
) then
5749 Candidate
:= Non_Limited_View
(Id
);
5750 Is_New_Candidate
:= True;
5752 -- Hide candidate because it is not used in a proper context
5756 Is_New_Candidate
:= False;
5760 -- Ada 2005 (AI-217): Handle shadow entities associated with types
5761 -- declared in limited-withed nested packages. We don't need to
5762 -- handle E_Incomplete_Subtype entities because the entities in
5763 -- the limited view are always E_Incomplete_Type entities (see
5764 -- Build_Limited_Views). Regarding the expression used to evaluate
5765 -- the scope, it is important to note that the limited view also
5766 -- has shadow entities associated nested packages. For this reason
5767 -- the correct scope of the entity is the scope of the real entity
5768 -- The non-limited view may itself be incomplete, in which case
5769 -- get the full view if available.
5771 elsif Ekind
(Id
) = E_Incomplete_Type
5772 and then From_Limited_With
(Id
)
5773 and then Present
(Non_Limited_View
(Id
))
5774 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5776 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5777 Is_New_Candidate
:= True;
5780 Is_New_Candidate
:= False;
5783 if Is_New_Candidate
then
5784 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5785 exit when Is_Visible_Lib_Unit
(Id
);
5787 exit when not Is_Hidden
(Id
);
5790 exit when Is_Immediately_Visible
(Id
);
5798 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5799 and then Is_Generic_Instance
(P_Name
)
5801 -- Expanded name denotes entity in (instance of) generic subprogram.
5802 -- The entity may be in the subprogram instance, or may denote one of
5803 -- the formals, which is declared in the enclosing wrapper package.
5805 P_Name
:= Scope
(P_Name
);
5807 Id
:= Current_Entity
(Selector
);
5808 while Present
(Id
) loop
5809 exit when Scope
(Id
) = P_Name
;
5814 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5815 Set_Etype
(N
, Any_Type
);
5817 -- If we are looking for an entity defined in System, try to find it
5818 -- in the child package that may have been provided as an extension
5819 -- to System. The Extend_System pragma will have supplied the name of
5820 -- the extension, which may have to be loaded.
5822 if Chars
(P_Name
) = Name_System
5823 and then Scope
(P_Name
) = Standard_Standard
5824 and then Present
(System_Extend_Unit
)
5825 and then Present_System_Aux
(N
)
5827 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5828 Find_Expanded_Name
(N
);
5831 elsif Nkind
(Selector
) = N_Operator_Symbol
5832 and then Has_Implicit_Operator
(N
)
5834 -- There is an implicit instance of the predefined operator in
5835 -- the given scope. The operator entity is defined in Standard.
5836 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5840 elsif Nkind
(Selector
) = N_Character_Literal
5841 and then Has_Implicit_Character_Literal
(N
)
5843 -- If there is no literal defined in the scope denoted by the
5844 -- prefix, the literal may belong to (a type derived from)
5845 -- Standard_Character, for which we have no explicit literals.
5850 -- If the prefix is a single concurrent object, use its name in
5851 -- the error message, rather than that of the anonymous type.
5853 if Is_Concurrent_Type
(P_Name
)
5854 and then Is_Internal_Name
(Chars
(P_Name
))
5856 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5858 Error_Msg_Node_2
:= P_Name
;
5861 if P_Name
= System_Aux_Id
then
5862 P_Name
:= Scope
(P_Name
);
5863 Set_Entity
(Prefix
(N
), P_Name
);
5866 if Present
(Candidate
) then
5868 -- If we know that the unit is a child unit we can give a more
5869 -- accurate error message.
5871 if Is_Child_Unit
(Candidate
) then
5873 -- If the candidate is a private child unit and we are in
5874 -- the visible part of a public unit, specialize the error
5875 -- message. There might be a private with_clause for it,
5876 -- but it is not currently active.
5878 if Is_Private_Descendant
(Candidate
)
5879 and then Ekind
(Current_Scope
) = E_Package
5880 and then not In_Private_Part
(Current_Scope
)
5881 and then not Is_Private_Descendant
(Current_Scope
)
5883 Error_Msg_N
("private child unit& is not visible here",
5886 -- Normal case where we have a missing with for a child unit
5889 Error_Msg_Qual_Level
:= 99;
5890 Error_Msg_NE
-- CODEFIX
5891 ("missing `WITH &;`", Selector
, Candidate
);
5892 Error_Msg_Qual_Level
:= 0;
5895 -- Here we don't know that this is a child unit
5898 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5902 -- Within the instantiation of a child unit, the prefix may
5903 -- denote the parent instance, but the selector has the name
5904 -- of the original child. That is to say, when A.B appears
5905 -- within an instantiation of generic child unit B, the scope
5906 -- stack includes an instance of A (P_Name) and an instance
5907 -- of B under some other name. We scan the scope to find this
5908 -- child instance, which is the desired entity.
5909 -- Note that the parent may itself be a child instance, if
5910 -- the reference is of the form A.B.C, in which case A.B has
5911 -- already been rewritten with the proper entity.
5913 if In_Open_Scopes
(P_Name
)
5914 and then Is_Generic_Instance
(P_Name
)
5917 Gen_Par
: constant Entity_Id
:=
5918 Generic_Parent
(Specification
5919 (Unit_Declaration_Node
(P_Name
)));
5920 S
: Entity_Id
:= Current_Scope
;
5924 for J
in reverse 0 .. Scope_Stack
.Last
loop
5925 S
:= Scope_Stack
.Table
(J
).Entity
;
5927 exit when S
= Standard_Standard
;
5929 if Ekind_In
(S
, E_Function
,
5933 P
:= Generic_Parent
(Specification
5934 (Unit_Declaration_Node
(S
)));
5936 -- Check that P is a generic child of the generic
5937 -- parent of the prefix.
5940 and then Chars
(P
) = Chars
(Selector
)
5941 and then Scope
(P
) = Gen_Par
5952 -- If this is a selection from Ada, System or Interfaces, then
5953 -- we assume a missing with for the corresponding package.
5955 if Is_Known_Unit
(N
) then
5956 if not Error_Posted
(N
) then
5957 Error_Msg_Node_2
:= Selector
;
5958 Error_Msg_N
-- CODEFIX
5959 ("missing `WITH &.&;`", Prefix
(N
));
5962 -- If this is a selection from a dummy package, then suppress
5963 -- the error message, of course the entity is missing if the
5964 -- package is missing.
5966 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
5969 -- Here we have the case of an undefined component
5973 -- The prefix may hide a homonym in the context that
5974 -- declares the desired entity. This error can use a
5975 -- specialized message.
5977 if In_Open_Scopes
(P_Name
) then
5979 H
: constant Entity_Id
:= Homonym
(P_Name
);
5983 and then Is_Compilation_Unit
(H
)
5985 (Is_Immediately_Visible
(H
)
5986 or else Is_Visible_Lib_Unit
(H
))
5988 Id
:= First_Entity
(H
);
5989 while Present
(Id
) loop
5990 if Chars
(Id
) = Chars
(Selector
) then
5991 Error_Msg_Qual_Level
:= 99;
5992 Error_Msg_Name_1
:= Chars
(Selector
);
5994 ("% not declared in&", N
, P_Name
);
5996 ("\use fully qualified name starting with "
5997 & "Standard to make& visible", N
, H
);
5998 Error_Msg_Qual_Level
:= 0;
6006 -- If not found, standard error message
6008 Error_Msg_NE
("& not declared in&", N
, Selector
);
6014 Error_Msg_NE
("& not declared in&", N
, Selector
);
6017 -- Check for misspelling of some entity in prefix
6019 Id
:= First_Entity
(P_Name
);
6020 while Present
(Id
) loop
6021 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6022 and then not Is_Internal_Name
(Chars
(Id
))
6024 Error_Msg_NE
-- CODEFIX
6025 ("possible misspelling of&", Selector
, Id
);
6032 -- Specialize the message if this may be an instantiation
6033 -- of a child unit that was not mentioned in the context.
6035 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6036 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6037 and then Is_Compilation_Unit
6038 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6040 Error_Msg_Node_2
:= Selector
;
6041 Error_Msg_N
-- CODEFIX
6042 ("\missing `WITH &.&;`", Prefix
(N
));
6052 if Comes_From_Source
(N
)
6053 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6054 and then Ekind
(Id
) = E_Access_Subprogram_Type
6055 and then Present
(Equivalent_Type
(Id
))
6057 -- If we are not actually generating distribution code (i.e. the
6058 -- current PCS is the dummy non-distributed version), then the
6059 -- Equivalent_Type will be missing, and Id should be treated as
6060 -- a regular access-to-subprogram type.
6062 Id
:= Equivalent_Type
(Id
);
6063 Set_Chars
(Selector
, Chars
(Id
));
6066 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6068 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6069 if From_Limited_With
(Id
)
6070 or else Is_Type
(Id
)
6071 or else Ekind
(Id
) = E_Package
6076 ("limited withed package can only be used to access "
6077 & "incomplete types", N
);
6081 if Is_Task_Type
(P_Name
)
6082 and then ((Ekind
(Id
) = E_Entry
6083 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6085 (Ekind
(Id
) = E_Entry_Family
6087 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6089 -- If both the task type and the entry are in scope, this may still
6090 -- be the expanded name of an entry formal.
6092 if In_Open_Scopes
(Id
)
6093 and then Nkind
(Parent
(N
)) = N_Selected_Component
6098 -- It is an entry call after all, either to the current task
6099 -- (which will deadlock) or to an enclosing task.
6101 Analyze_Selected_Component
(N
);
6106 Change_Selected_Component_To_Expanded_Name
(N
);
6108 -- Set appropriate type
6110 if Is_Type
(Id
) then
6113 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6116 -- Do style check and generate reference, but skip both steps if this
6117 -- entity has homonyms, since we may not have the right homonym set yet.
6118 -- The proper homonym will be set during the resolve phase.
6120 if Has_Homonym
(Id
) then
6124 Set_Entity_Or_Discriminal
(N
, Id
);
6128 Generate_Reference
(Id
, N
, 'm');
6130 Generate_Reference
(Id
, N
, 'r');
6132 Deferred_References
.Append
((Id
, N
));
6136 -- Check for violation of No_Wide_Characters
6138 Check_Wide_Character_Restriction
(Id
, N
);
6140 -- If the Ekind of the entity is Void, it means that all homonyms are
6141 -- hidden from all visibility (RM 8.3(5,14-20)).
6143 if Ekind
(Id
) = E_Void
then
6144 Premature_Usage
(N
);
6146 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6148 H
: Entity_Id
:= Homonym
(Id
);
6151 while Present
(H
) loop
6152 if Scope
(H
) = Scope
(Id
)
6153 and then (not Is_Hidden
(H
)
6154 or else Is_Immediately_Visible
(H
))
6156 Collect_Interps
(N
);
6163 -- If an extension of System is present, collect possible explicit
6164 -- overloadings declared in the extension.
6166 if Chars
(P_Name
) = Name_System
6167 and then Scope
(P_Name
) = Standard_Standard
6168 and then Present
(System_Extend_Unit
)
6169 and then Present_System_Aux
(N
)
6171 H
:= Current_Entity
(Id
);
6173 while Present
(H
) loop
6174 if Scope
(H
) = System_Aux_Id
then
6175 Add_One_Interp
(N
, H
, Etype
(H
));
6184 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6185 and then Scope
(Id
) /= Standard_Standard
6187 -- In addition to user-defined operators in the given scope, there
6188 -- may be an implicit instance of the predefined operator. The
6189 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6190 -- and added to the interpretations. Procedure Add_One_Interp will
6191 -- determine which hides which.
6193 if Has_Implicit_Operator
(N
) then
6198 -- If there is a single interpretation for N we can generate a
6199 -- reference to the unique entity found.
6201 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6202 Generate_Reference
(Id
, N
);
6204 end Find_Expanded_Name
;
6206 -------------------------
6207 -- Find_Renamed_Entity --
6208 -------------------------
6210 function Find_Renamed_Entity
6214 Is_Actual
: Boolean := False) return Entity_Id
6217 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6223 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6224 -- If the renamed entity is an implicit operator, check whether it is
6225 -- visible because its operand type is properly visible. This check
6226 -- applies to explicit renamed entities that appear in the source in a
6227 -- renaming declaration or a formal subprogram instance, but not to
6228 -- default generic actuals with a name.
6230 function Report_Overload
return Entity_Id
;
6231 -- List possible interpretations, and specialize message in the
6232 -- case of a generic actual.
6234 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6235 -- Determine whether a candidate subprogram is defined within the
6236 -- enclosing instance. If yes, it has precedence over outer candidates.
6238 --------------------------
6239 -- Is_Visible_Operation --
6240 --------------------------
6242 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6248 if Ekind
(Op
) /= E_Operator
6249 or else Scope
(Op
) /= Standard_Standard
6250 or else (In_Instance
6251 and then (not Is_Actual
6252 or else Present
(Enclosing_Instance
)))
6257 -- For a fixed point type operator, check the resulting type,
6258 -- because it may be a mixed mode integer * fixed operation.
6260 if Present
(Next_Formal
(First_Formal
(New_S
)))
6261 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6263 Typ
:= Etype
(New_S
);
6265 Typ
:= Etype
(First_Formal
(New_S
));
6268 Btyp
:= Base_Type
(Typ
);
6270 if Nkind
(Nam
) /= N_Expanded_Name
then
6271 return (In_Open_Scopes
(Scope
(Btyp
))
6272 or else Is_Potentially_Use_Visible
(Btyp
)
6273 or else In_Use
(Btyp
)
6274 or else In_Use
(Scope
(Btyp
)));
6277 Scop
:= Entity
(Prefix
(Nam
));
6279 if Ekind
(Scop
) = E_Package
6280 and then Present
(Renamed_Object
(Scop
))
6282 Scop
:= Renamed_Object
(Scop
);
6285 -- Operator is visible if prefix of expanded name denotes
6286 -- scope of type, or else type is defined in System_Aux
6287 -- and the prefix denotes System.
6289 return Scope
(Btyp
) = Scop
6290 or else (Scope
(Btyp
) = System_Aux_Id
6291 and then Scope
(Scope
(Btyp
)) = Scop
);
6294 end Is_Visible_Operation
;
6300 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6304 Sc
:= Scope
(Inner
);
6305 while Sc
/= Standard_Standard
loop
6316 ---------------------
6317 -- Report_Overload --
6318 ---------------------
6320 function Report_Overload
return Entity_Id
is
6323 Error_Msg_NE
-- CODEFIX
6324 ("ambiguous actual subprogram&, " &
6325 "possible interpretations:", N
, Nam
);
6327 Error_Msg_N
-- CODEFIX
6328 ("ambiguous subprogram, " &
6329 "possible interpretations:", N
);
6332 List_Interps
(Nam
, N
);
6334 end Report_Overload
;
6336 -- Start of processing for Find_Renamed_Entity
6340 Candidate_Renaming
:= Empty
;
6342 if Is_Overloaded
(Nam
) then
6343 Get_First_Interp
(Nam
, Ind
, It
);
6344 while Present
(It
.Nam
) loop
6345 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6346 and then Is_Visible_Operation
(It
.Nam
)
6348 if Old_S
/= Any_Id
then
6350 -- Note: The call to Disambiguate only happens if a
6351 -- previous interpretation was found, in which case I1
6352 -- has received a value.
6354 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6356 if It1
= No_Interp
then
6357 Inst
:= Enclosing_Instance
;
6359 if Present
(Inst
) then
6360 if Within
(It
.Nam
, Inst
) then
6361 if Within
(Old_S
, Inst
) then
6363 -- Choose the innermost subprogram, which would
6364 -- have hidden the outer one in the generic.
6366 if Scope_Depth
(It
.Nam
) <
6375 elsif Within
(Old_S
, Inst
) then
6379 return Report_Overload
;
6382 -- If not within an instance, ambiguity is real
6385 return Report_Overload
;
6399 Present
(First_Formal
(It
.Nam
))
6400 and then Present
(First_Formal
(New_S
))
6401 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6402 Base_Type
(Etype
(First_Formal
(New_S
))))
6404 Candidate_Renaming
:= It
.Nam
;
6407 Get_Next_Interp
(Ind
, It
);
6410 Set_Entity
(Nam
, Old_S
);
6412 if Old_S
/= Any_Id
then
6413 Set_Is_Overloaded
(Nam
, False);
6416 -- Non-overloaded case
6419 if Is_Actual
and then Present
(Enclosing_Instance
) then
6420 Old_S
:= Entity
(Nam
);
6422 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6423 Candidate_Renaming
:= New_S
;
6425 if Is_Visible_Operation
(Entity
(Nam
)) then
6426 Old_S
:= Entity
(Nam
);
6429 elsif Present
(First_Formal
(Entity
(Nam
)))
6430 and then Present
(First_Formal
(New_S
))
6431 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6432 Base_Type
(Etype
(First_Formal
(New_S
))))
6434 Candidate_Renaming
:= Entity
(Nam
);
6439 end Find_Renamed_Entity
;
6441 -----------------------------
6442 -- Find_Selected_Component --
6443 -----------------------------
6445 procedure Find_Selected_Component
(N
: Node_Id
) is
6446 P
: constant Node_Id
:= Prefix
(N
);
6449 -- Entity denoted by prefix
6456 function Available_Subtype
return Boolean;
6457 -- A small optimization: if the prefix is constrained and the component
6458 -- is an array type we may already have a usable subtype for it, so we
6459 -- can use it rather than generating a new one, because the bounds
6460 -- will be the values of the discriminants and not discriminant refs.
6461 -- This simplifies value tracing in GNATProve. For consistency, both
6462 -- the entity name and the subtype come from the constrained component.
6464 function Is_Reference_In_Subunit
return Boolean;
6465 -- In a subunit, the scope depth is not a proper measure of hiding,
6466 -- because the context of the proper body may itself hide entities in
6467 -- parent units. This rare case requires inspecting the tree directly
6468 -- because the proper body is inserted in the main unit and its context
6469 -- is simply added to that of the parent.
6471 -----------------------
6472 -- Available_Subtype --
6473 -----------------------
6475 function Available_Subtype
return Boolean is
6479 Comp
:= First_Entity
(Etype
(P
));
6480 while Present
(Comp
) loop
6481 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6482 Set_Etype
(N
, Etype
(Comp
));
6483 Set_Entity
(Selector_Name
(N
), Comp
);
6484 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6488 Next_Component
(Comp
);
6492 end Available_Subtype
;
6494 -----------------------------
6495 -- Is_Reference_In_Subunit --
6496 -----------------------------
6498 function Is_Reference_In_Subunit
return Boolean is
6500 Comp_Unit
: Node_Id
;
6504 while Present
(Comp_Unit
)
6505 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6507 Comp_Unit
:= Parent
(Comp_Unit
);
6510 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6514 -- Now check whether the package is in the context of the subunit
6516 Clause
:= First
(Context_Items
(Comp_Unit
));
6517 while Present
(Clause
) loop
6518 if Nkind
(Clause
) = N_With_Clause
6519 and then Entity
(Name
(Clause
)) = P_Name
6524 Clause
:= Next
(Clause
);
6528 end Is_Reference_In_Subunit
;
6530 -- Start of processing for Find_Selected_Component
6535 if Nkind
(P
) = N_Error
then
6539 -- Selector name cannot be a character literal or an operator symbol in
6540 -- SPARK, except for the operator symbol in a renaming.
6542 if Restriction_Check_Required
(SPARK_05
) then
6543 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6544 Check_SPARK_05_Restriction
6545 ("character literal cannot be prefixed", N
);
6546 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6547 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6549 Check_SPARK_05_Restriction
6550 ("operator symbol cannot be prefixed", N
);
6554 -- If the selector already has an entity, the node has been constructed
6555 -- in the course of expansion, and is known to be valid. Do not verify
6556 -- that it is defined for the type (it may be a private component used
6557 -- in the expansion of record equality).
6559 if Present
(Entity
(Selector_Name
(N
))) then
6560 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6562 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6563 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6567 Set_Etype
(Sel_Name
, Etype
(Selector
));
6569 if not Is_Entity_Name
(P
) then
6573 -- Build an actual subtype except for the first parameter
6574 -- of an init proc, where this actual subtype is by
6575 -- definition incorrect, since the object is uninitialized
6576 -- (and does not even have defined discriminants etc.)
6578 if Is_Entity_Name
(P
)
6579 and then Ekind
(Entity
(P
)) = E_Function
6581 Nam
:= New_Copy
(P
);
6583 if Is_Overloaded
(P
) then
6584 Save_Interps
(P
, Nam
);
6587 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6589 Analyze_Selected_Component
(N
);
6592 elsif Ekind
(Selector
) = E_Component
6593 and then (not Is_Entity_Name
(P
)
6594 or else Chars
(Entity
(P
)) /= Name_uInit
)
6596 -- Check if we already have an available subtype we can use
6598 if Ekind
(Etype
(P
)) = E_Record_Subtype
6599 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6600 and then Is_Array_Type
(Etype
(Selector
))
6601 and then not Is_Packed
(Etype
(Selector
))
6602 and then Available_Subtype
6606 -- Do not build the subtype when referencing components of
6607 -- dispatch table wrappers. Required to avoid generating
6608 -- elaboration code with HI runtimes. JVM and .NET use a
6609 -- modified version of Ada.Tags which does not contain RE_
6610 -- Dispatch_Table_Wrapper and RE_No_Dispatch_Table_Wrapper.
6611 -- Avoid raising RE_Not_Available exception in those cases.
6613 elsif VM_Target
= No_VM
6614 and then RTU_Loaded
(Ada_Tags
)
6616 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6617 and then Scope
(Selector
) =
6618 RTE
(RE_Dispatch_Table_Wrapper
))
6620 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6621 and then Scope
(Selector
) =
6622 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6627 Build_Actual_Subtype_Of_Component
6628 (Etype
(Selector
), N
);
6635 if No
(C_Etype
) then
6636 C_Etype
:= Etype
(Selector
);
6638 Insert_Action
(N
, C_Etype
);
6639 C_Etype
:= Defining_Identifier
(C_Etype
);
6642 Set_Etype
(N
, C_Etype
);
6645 -- If this is the name of an entry or protected operation, and
6646 -- the prefix is an access type, insert an explicit dereference,
6647 -- so that entry calls are treated uniformly.
6649 if Is_Access_Type
(Etype
(P
))
6650 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6653 New_P
: constant Node_Id
:=
6654 Make_Explicit_Dereference
(Sloc
(P
),
6655 Prefix
=> Relocate_Node
(P
));
6658 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6662 -- If the selected component appears within a default expression
6663 -- and it has an actual subtype, the pre-analysis has not yet
6664 -- completed its analysis, because Insert_Actions is disabled in
6665 -- that context. Within the init proc of the enclosing type we
6666 -- must complete this analysis, if an actual subtype was created.
6668 elsif Inside_Init_Proc
then
6670 Typ
: constant Entity_Id
:= Etype
(N
);
6671 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6673 if Nkind
(Decl
) = N_Subtype_Declaration
6674 and then not Analyzed
(Decl
)
6675 and then Is_List_Member
(Decl
)
6676 and then No
(Parent
(Decl
))
6679 Insert_Action
(N
, Decl
);
6686 elsif Is_Entity_Name
(P
) then
6687 P_Name
:= Entity
(P
);
6689 -- The prefix may denote an enclosing type which is the completion
6690 -- of an incomplete type declaration.
6692 if Is_Type
(P_Name
) then
6693 Set_Entity
(P
, Get_Full_View
(P_Name
));
6694 Set_Etype
(P
, Entity
(P
));
6695 P_Name
:= Entity
(P
);
6698 P_Type
:= Base_Type
(Etype
(P
));
6700 if Debug_Flag_E
then
6701 Write_Str
("Found prefix type to be ");
6702 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6705 -- The designated type may be a limited view with no components.
6706 -- Check whether the non-limited view is available, because in some
6707 -- cases this will not be set when instlling the context.
6709 if Is_Access_Type
(P_Type
) then
6711 D
: constant Entity_Id
:= Directly_Designated_Type
(P_Type
);
6713 if Is_Incomplete_Type
(D
)
6714 and then not Is_Class_Wide_Type
(D
)
6715 and then From_Limited_With
(D
)
6716 and then Present
(Non_Limited_View
(D
))
6717 and then not Is_Class_Wide_Type
(Non_Limited_View
(D
))
6719 Set_Directly_Designated_Type
(P_Type
, Non_Limited_View
(D
));
6724 -- First check for components of a record object (not the
6725 -- result of a call, which is handled below).
6727 if Is_Appropriate_For_Record
(P_Type
)
6728 and then not Is_Overloadable
(P_Name
)
6729 and then not Is_Type
(P_Name
)
6731 -- Selected component of record. Type checking will validate
6732 -- name of selector.
6734 -- ??? Could we rewrite an implicit dereference into an explicit
6737 Analyze_Selected_Component
(N
);
6739 -- Reference to type name in predicate/invariant expression
6741 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6742 and then not In_Open_Scopes
(P_Name
)
6743 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6744 or else not In_Open_Scopes
(Etype
(P_Name
)))
6746 -- Call to protected operation or entry. Type checking is
6747 -- needed on the prefix.
6749 Analyze_Selected_Component
(N
);
6751 elsif (In_Open_Scopes
(P_Name
)
6752 and then Ekind
(P_Name
) /= E_Void
6753 and then not Is_Overloadable
(P_Name
))
6754 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6755 and then In_Open_Scopes
(Etype
(P_Name
)))
6757 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6758 -- enclosing construct that is not a subprogram or accept.
6760 Find_Expanded_Name
(N
);
6762 elsif Ekind
(P_Name
) = E_Package
then
6763 Find_Expanded_Name
(N
);
6765 elsif Is_Overloadable
(P_Name
) then
6767 -- The subprogram may be a renaming (of an enclosing scope) as
6768 -- in the case of the name of the generic within an instantiation.
6770 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6771 and then Present
(Alias
(P_Name
))
6772 and then Is_Generic_Instance
(Alias
(P_Name
))
6774 P_Name
:= Alias
(P_Name
);
6777 if Is_Overloaded
(P
) then
6779 -- The prefix must resolve to a unique enclosing construct
6782 Found
: Boolean := False;
6787 Get_First_Interp
(P
, Ind
, It
);
6788 while Present
(It
.Nam
) loop
6789 if In_Open_Scopes
(It
.Nam
) then
6792 "prefix must be unique enclosing scope", N
);
6793 Set_Entity
(N
, Any_Id
);
6794 Set_Etype
(N
, Any_Type
);
6803 Get_Next_Interp
(Ind
, It
);
6808 if In_Open_Scopes
(P_Name
) then
6809 Set_Entity
(P
, P_Name
);
6810 Set_Is_Overloaded
(P
, False);
6811 Find_Expanded_Name
(N
);
6814 -- If no interpretation as an expanded name is possible, it
6815 -- must be a selected component of a record returned by a
6816 -- function call. Reformat prefix as a function call, the rest
6817 -- is done by type resolution.
6819 -- Error if the prefix is procedure or entry, as is P.X
6821 if Ekind
(P_Name
) /= E_Function
6823 (not Is_Overloaded
(P
)
6824 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6826 -- Prefix may mention a package that is hidden by a local
6827 -- declaration: let the user know. Scan the full homonym
6828 -- chain, the candidate package may be anywhere on it.
6830 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6831 P_Name
:= Current_Entity
(P_Name
);
6833 while Present
(P_Name
) loop
6834 exit when Ekind
(P_Name
) = E_Package
;
6835 P_Name
:= Homonym
(P_Name
);
6838 if Present
(P_Name
) then
6839 if not Is_Reference_In_Subunit
then
6840 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6842 ("package& is hidden by declaration#", N
, P_Name
);
6845 Set_Entity
(Prefix
(N
), P_Name
);
6846 Find_Expanded_Name
(N
);
6850 P_Name
:= Entity
(Prefix
(N
));
6855 ("invalid prefix in selected component&", N
, P_Name
);
6856 Change_Selected_Component_To_Expanded_Name
(N
);
6857 Set_Entity
(N
, Any_Id
);
6858 Set_Etype
(N
, Any_Type
);
6860 -- Here we have a function call, so do the reformatting
6863 Nam
:= New_Copy
(P
);
6864 Save_Interps
(P
, Nam
);
6866 -- We use Replace here because this is one of those cases
6867 -- where the parser has missclassified the node, and we
6868 -- fix things up and then do the semantic analysis on the
6869 -- fixed up node. Normally we do this using one of the
6870 -- Sinfo.CN routines, but this is too tricky for that.
6872 -- Note that using Rewrite would be wrong, because we
6873 -- would have a tree where the original node is unanalyzed,
6874 -- and this violates the required interface for ASIS.
6877 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6879 -- Now analyze the reformatted node
6882 Analyze_Selected_Component
(N
);
6886 -- Remaining cases generate various error messages
6889 -- Format node as expanded name, to avoid cascaded errors
6891 Change_Selected_Component_To_Expanded_Name
(N
);
6892 Set_Entity
(N
, Any_Id
);
6893 Set_Etype
(N
, Any_Type
);
6895 -- Issue error message, but avoid this if error issued already.
6896 -- Use identifier of prefix if one is available.
6898 if P_Name
= Any_Id
then
6901 elsif Ekind
(P_Name
) = E_Void
then
6902 Premature_Usage
(P
);
6904 elsif Nkind
(P
) /= N_Attribute_Reference
then
6906 -- This may have been meant as a prefixed call to a primitive
6907 -- of an untagged type.
6910 F
: constant Entity_Id
:=
6911 Current_Entity
(Selector_Name
(N
));
6914 and then Is_Overloadable
(F
)
6915 and then Present
(First_Entity
(F
))
6916 and then Etype
(First_Entity
(F
)) = Etype
(P
)
6917 and then not Is_Tagged_Type
(Etype
(P
))
6920 ("prefixed call is only allowed for objects "
6921 & "of a tagged type", N
);
6925 Error_Msg_N
("invalid prefix in selected component&", P
);
6927 if Is_Access_Type
(P_Type
)
6928 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
6931 ("\dereference must not be of an incomplete type "
6932 & "(RM 3.10.1)", P
);
6936 Error_Msg_N
("invalid prefix in selected component", P
);
6940 -- Selector name is restricted in SPARK
6942 if Nkind
(N
) = N_Expanded_Name
6943 and then Restriction_Check_Required
(SPARK_05
)
6945 if Is_Subprogram
(P_Name
) then
6946 Check_SPARK_05_Restriction
6947 ("prefix of expanded name cannot be a subprogram", P
);
6948 elsif Ekind
(P_Name
) = E_Loop
then
6949 Check_SPARK_05_Restriction
6950 ("prefix of expanded name cannot be a loop statement", P
);
6955 -- If prefix is not the name of an entity, it must be an expression,
6956 -- whose type is appropriate for a record. This is determined by
6959 Analyze_Selected_Component
(N
);
6962 Analyze_Dimension
(N
);
6963 end Find_Selected_Component
;
6969 procedure Find_Type
(N
: Node_Id
) is
6979 elsif Nkind
(N
) = N_Attribute_Reference
then
6981 -- Class attribute. This is not valid in Ada 83 mode, but we do not
6982 -- need to enforce that at this point, since the declaration of the
6983 -- tagged type in the prefix would have been flagged already.
6985 if Attribute_Name
(N
) = Name_Class
then
6986 Check_Restriction
(No_Dispatch
, N
);
6987 Find_Type
(Prefix
(N
));
6989 -- Propagate error from bad prefix
6991 if Etype
(Prefix
(N
)) = Any_Type
then
6992 Set_Entity
(N
, Any_Type
);
6993 Set_Etype
(N
, Any_Type
);
6997 T
:= Base_Type
(Entity
(Prefix
(N
)));
6999 -- Case where type is not known to be tagged. Its appearance in
7000 -- the prefix of the 'Class attribute indicates that the full view
7003 if not Is_Tagged_Type
(T
) then
7004 if Ekind
(T
) = E_Incomplete_Type
then
7006 -- It is legal to denote the class type of an incomplete
7007 -- type. The full type will have to be tagged, of course.
7008 -- In Ada 2005 this usage is declared obsolescent, so we
7009 -- warn accordingly. This usage is only legal if the type
7010 -- is completed in the current scope, and not for a limited
7013 if Ada_Version
>= Ada_2005
then
7015 -- Test whether the Available_View of a limited type view
7016 -- is tagged, since the limited view may not be marked as
7017 -- tagged if the type itself has an untagged incomplete
7018 -- type view in its package.
7020 if From_Limited_With
(T
)
7021 and then not Is_Tagged_Type
(Available_View
(T
))
7024 ("prefix of Class attribute must be tagged", N
);
7025 Set_Etype
(N
, Any_Type
);
7026 Set_Entity
(N
, Any_Type
);
7029 -- ??? This test is temporarily disabled (always
7030 -- False) because it causes an unwanted warning on
7031 -- GNAT sources (built with -gnatg, which includes
7032 -- Warn_On_Obsolescent_ Feature). Once this issue
7033 -- is cleared in the sources, it can be enabled.
7035 elsif Warn_On_Obsolescent_Feature
and then False then
7037 ("applying 'Class to an untagged incomplete type"
7038 & " is an obsolescent feature (RM J.11)?r?", N
);
7042 Set_Is_Tagged_Type
(T
);
7043 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7044 Make_Class_Wide_Type
(T
);
7045 Set_Entity
(N
, Class_Wide_Type
(T
));
7046 Set_Etype
(N
, Class_Wide_Type
(T
));
7048 elsif Ekind
(T
) = E_Private_Type
7049 and then not Is_Generic_Type
(T
)
7050 and then In_Private_Part
(Scope
(T
))
7052 -- The Class attribute can be applied to an untagged private
7053 -- type fulfilled by a tagged type prior to the full type
7054 -- declaration (but only within the parent package's private
7055 -- part). Create the class-wide type now and check that the
7056 -- full type is tagged later during its analysis. Note that
7057 -- we do not mark the private type as tagged, unlike the
7058 -- case of incomplete types, because the type must still
7059 -- appear untagged to outside units.
7061 if No
(Class_Wide_Type
(T
)) then
7062 Make_Class_Wide_Type
(T
);
7065 Set_Entity
(N
, Class_Wide_Type
(T
));
7066 Set_Etype
(N
, Class_Wide_Type
(T
));
7069 -- Should we introduce a type Any_Tagged and use Wrong_Type
7070 -- here, it would be a bit more consistent???
7073 ("tagged type required, found}",
7074 Prefix
(N
), First_Subtype
(T
));
7075 Set_Entity
(N
, Any_Type
);
7079 -- Case of tagged type
7082 if Is_Concurrent_Type
(T
) then
7083 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7085 -- Previous error. Use current type, which at least
7086 -- provides some operations.
7088 C
:= Entity
(Prefix
(N
));
7091 C
:= Class_Wide_Type
7092 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7096 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7099 Set_Entity_With_Checks
(N
, C
);
7100 Generate_Reference
(C
, N
);
7104 -- Base attribute, not allowed in Ada 83
7106 elsif Attribute_Name
(N
) = Name_Base
then
7107 Error_Msg_Name_1
:= Name_Base
;
7108 Check_SPARK_05_Restriction
7109 ("attribute% is only allowed as prefix of another attribute", N
);
7111 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7113 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7116 Find_Type
(Prefix
(N
));
7117 Typ
:= Entity
(Prefix
(N
));
7119 if Ada_Version
>= Ada_95
7120 and then not Is_Scalar_Type
(Typ
)
7121 and then not Is_Generic_Type
(Typ
)
7124 ("prefix of Base attribute must be scalar type",
7127 elsif Warn_On_Redundant_Constructs
7128 and then Base_Type
(Typ
) = Typ
7130 Error_Msg_NE
-- CODEFIX
7131 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7134 T
:= Base_Type
(Typ
);
7136 -- Rewrite attribute reference with type itself (see similar
7137 -- processing in Analyze_Attribute, case Base). Preserve prefix
7138 -- if present, for other legality checks.
7140 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7142 Make_Expanded_Name
(Sloc
(N
),
7144 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7145 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7148 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7155 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7157 -- This is handled in Analyze_Attribute
7161 -- All other attributes are invalid in a subtype mark
7164 Error_Msg_N
("invalid attribute in subtype mark", N
);
7170 if Is_Entity_Name
(N
) then
7171 T_Name
:= Entity
(N
);
7173 Error_Msg_N
("subtype mark required in this context", N
);
7174 Set_Etype
(N
, Any_Type
);
7178 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7180 -- Undefined id. Make it into a valid type
7182 Set_Entity
(N
, Any_Type
);
7184 elsif not Is_Type
(T_Name
)
7185 and then T_Name
/= Standard_Void_Type
7187 Error_Msg_Sloc
:= Sloc
(T_Name
);
7188 Error_Msg_N
("subtype mark required in this context", N
);
7189 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7190 Set_Entity
(N
, Any_Type
);
7193 -- If the type is an incomplete type created to handle
7194 -- anonymous access components of a record type, then the
7195 -- incomplete type is the visible entity and subsequent
7196 -- references will point to it. Mark the original full
7197 -- type as referenced, to prevent spurious warnings.
7199 if Is_Incomplete_Type
(T_Name
)
7200 and then Present
(Full_View
(T_Name
))
7201 and then not Comes_From_Source
(T_Name
)
7203 Set_Referenced
(Full_View
(T_Name
));
7206 T_Name
:= Get_Full_View
(T_Name
);
7208 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7209 -- limited-with clauses
7211 if From_Limited_With
(T_Name
)
7212 and then Ekind
(T_Name
) in Incomplete_Kind
7213 and then Present
(Non_Limited_View
(T_Name
))
7214 and then Is_Interface
(Non_Limited_View
(T_Name
))
7216 T_Name
:= Non_Limited_View
(T_Name
);
7219 if In_Open_Scopes
(T_Name
) then
7220 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7222 -- In Ada 2005, a task name can be used in an access
7223 -- definition within its own body. It cannot be used
7224 -- in the discriminant part of the task declaration,
7225 -- nor anywhere else in the declaration because entries
7226 -- cannot have access parameters.
7228 if Ada_Version
>= Ada_2005
7229 and then Nkind
(Parent
(N
)) = N_Access_Definition
7231 Set_Entity
(N
, T_Name
);
7232 Set_Etype
(N
, T_Name
);
7234 if Has_Completion
(T_Name
) then
7239 ("task type cannot be used as type mark " &
7240 "within its own declaration", N
);
7245 ("task type cannot be used as type mark " &
7246 "within its own spec or body", N
);
7249 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7251 -- In Ada 2005, a protected name can be used in an access
7252 -- definition within its own body.
7254 if Ada_Version
>= Ada_2005
7255 and then Nkind
(Parent
(N
)) = N_Access_Definition
7257 Set_Entity
(N
, T_Name
);
7258 Set_Etype
(N
, T_Name
);
7263 ("protected type cannot be used as type mark " &
7264 "within its own spec or body", N
);
7268 Error_Msg_N
("type declaration cannot refer to itself", N
);
7271 Set_Etype
(N
, Any_Type
);
7272 Set_Entity
(N
, Any_Type
);
7273 Set_Error_Posted
(T_Name
);
7277 Set_Entity
(N
, T_Name
);
7278 Set_Etype
(N
, T_Name
);
7282 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7283 if Is_Fixed_Point_Type
(Etype
(N
)) then
7284 Check_Restriction
(No_Fixed_Point
, N
);
7285 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7286 Check_Restriction
(No_Floating_Point
, N
);
7289 -- A Ghost type must appear in a specific context
7291 if Is_Ghost_Entity
(Etype
(N
)) then
7292 Check_Ghost_Context
(Etype
(N
), N
);
7297 ------------------------------------
7298 -- Has_Implicit_Character_Literal --
7299 ------------------------------------
7301 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7303 Found
: Boolean := False;
7304 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7305 Priv_Id
: Entity_Id
:= Empty
;
7308 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7309 Priv_Id
:= First_Private_Entity
(P
);
7312 if P
= Standard_Standard
then
7313 Change_Selected_Component_To_Expanded_Name
(N
);
7314 Rewrite
(N
, Selector_Name
(N
));
7316 Set_Etype
(Original_Node
(N
), Standard_Character
);
7320 Id
:= First_Entity
(P
);
7321 while Present
(Id
) and then Id
/= Priv_Id
loop
7322 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7324 -- We replace the node with the literal itself, resolve as a
7325 -- character, and set the type correctly.
7328 Change_Selected_Component_To_Expanded_Name
(N
);
7329 Rewrite
(N
, Selector_Name
(N
));
7332 Set_Etype
(Original_Node
(N
), Id
);
7336 -- More than one type derived from Character in given scope.
7337 -- Collect all possible interpretations.
7339 Add_One_Interp
(N
, Id
, Id
);
7347 end Has_Implicit_Character_Literal
;
7349 ----------------------
7350 -- Has_Private_With --
7351 ----------------------
7353 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7354 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7358 Item
:= First
(Context_Items
(Comp_Unit
));
7359 while Present
(Item
) loop
7360 if Nkind
(Item
) = N_With_Clause
7361 and then Private_Present
(Item
)
7362 and then Entity
(Name
(Item
)) = E
7371 end Has_Private_With
;
7373 ---------------------------
7374 -- Has_Implicit_Operator --
7375 ---------------------------
7377 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7378 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7379 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7381 Priv_Id
: Entity_Id
:= Empty
;
7383 procedure Add_Implicit_Operator
7385 Op_Type
: Entity_Id
:= Empty
);
7386 -- Add implicit interpretation to node N, using the type for which a
7387 -- predefined operator exists. If the operator yields a boolean type,
7388 -- the Operand_Type is implicitly referenced by the operator, and a
7389 -- reference to it must be generated.
7391 ---------------------------
7392 -- Add_Implicit_Operator --
7393 ---------------------------
7395 procedure Add_Implicit_Operator
7397 Op_Type
: Entity_Id
:= Empty
)
7399 Predef_Op
: Entity_Id
;
7402 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7403 while Present
(Predef_Op
)
7404 and then Scope
(Predef_Op
) /= Standard_Standard
7406 Predef_Op
:= Homonym
(Predef_Op
);
7409 if Nkind
(N
) = N_Selected_Component
then
7410 Change_Selected_Component_To_Expanded_Name
(N
);
7413 -- If the context is an unanalyzed function call, determine whether
7414 -- a binary or unary interpretation is required.
7416 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7418 Is_Binary_Call
: constant Boolean :=
7420 (Next
(First
(Expressions
(Parent
(N
)))));
7421 Is_Binary_Op
: constant Boolean :=
7423 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7424 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7427 if Is_Binary_Call
then
7428 if Is_Binary_Op
then
7429 Add_One_Interp
(N
, Predef_Op
, T
);
7431 Add_One_Interp
(N
, Predef_Op2
, T
);
7435 if not Is_Binary_Op
then
7436 Add_One_Interp
(N
, Predef_Op
, T
);
7438 Add_One_Interp
(N
, Predef_Op2
, T
);
7444 Add_One_Interp
(N
, Predef_Op
, T
);
7446 -- For operators with unary and binary interpretations, if
7447 -- context is not a call, add both
7449 if Present
(Homonym
(Predef_Op
)) then
7450 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7454 -- The node is a reference to a predefined operator, and
7455 -- an implicit reference to the type of its operands.
7457 if Present
(Op_Type
) then
7458 Generate_Operator_Reference
(N
, Op_Type
);
7460 Generate_Operator_Reference
(N
, T
);
7462 end Add_Implicit_Operator
;
7464 -- Start of processing for Has_Implicit_Operator
7467 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7468 Priv_Id
:= First_Private_Entity
(P
);
7471 Id
:= First_Entity
(P
);
7475 -- Boolean operators: an implicit declaration exists if the scope
7476 -- contains a declaration for a derived Boolean type, or for an
7477 -- array of Boolean type.
7479 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7480 while Id
/= Priv_Id
loop
7481 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7482 Add_Implicit_Operator
(Id
);
7489 -- Equality: look for any non-limited type (result is Boolean)
7491 when Name_Op_Eq | Name_Op_Ne
=>
7492 while Id
/= Priv_Id
loop
7494 and then not Is_Limited_Type
(Id
)
7495 and then Is_Base_Type
(Id
)
7497 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7504 -- Comparison operators: scalar type, or array of scalar
7506 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7507 while Id
/= Priv_Id
loop
7508 if (Is_Scalar_Type
(Id
)
7509 or else (Is_Array_Type
(Id
)
7510 and then Is_Scalar_Type
(Component_Type
(Id
))))
7511 and then Is_Base_Type
(Id
)
7513 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7520 -- Arithmetic operators: any numeric type
7530 while Id
/= Priv_Id
loop
7531 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7532 Add_Implicit_Operator
(Id
);
7539 -- Concatenation: any one-dimensional array type
7541 when Name_Op_Concat
=>
7542 while Id
/= Priv_Id
loop
7543 if Is_Array_Type
(Id
)
7544 and then Number_Dimensions
(Id
) = 1
7545 and then Is_Base_Type
(Id
)
7547 Add_Implicit_Operator
(Id
);
7554 -- What is the others condition here? Should we be using a
7555 -- subtype of Name_Id that would restrict to operators ???
7557 when others => null;
7560 -- If we fall through, then we do not have an implicit operator
7564 end Has_Implicit_Operator
;
7566 -----------------------------------
7567 -- Has_Loop_In_Inner_Open_Scopes --
7568 -----------------------------------
7570 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7572 -- Several scope stacks are maintained by Scope_Stack. The base of the
7573 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7574 -- flag in the scope stack entry. Note that the scope stacks used to
7575 -- simply be delimited implicitly by the presence of Standard_Standard
7576 -- at their base, but there now are cases where this is not sufficient
7577 -- because Standard_Standard actually may appear in the middle of the
7578 -- active set of scopes.
7580 for J
in reverse 0 .. Scope_Stack
.Last
loop
7582 -- S was reached without seing a loop scope first
7584 if Scope_Stack
.Table
(J
).Entity
= S
then
7587 -- S was not yet reached, so it contains at least one inner loop
7589 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7593 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7594 -- cases where Standard_Standard appears in the middle of the active
7595 -- set of scopes. This affects the declaration and overriding of
7596 -- private inherited operations in instantiations of generic child
7599 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7602 raise Program_Error
; -- unreachable
7603 end Has_Loop_In_Inner_Open_Scopes
;
7605 --------------------
7606 -- In_Open_Scopes --
7607 --------------------
7609 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7611 -- Several scope stacks are maintained by Scope_Stack. The base of the
7612 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7613 -- flag in the scope stack entry. Note that the scope stacks used to
7614 -- simply be delimited implicitly by the presence of Standard_Standard
7615 -- at their base, but there now are cases where this is not sufficient
7616 -- because Standard_Standard actually may appear in the middle of the
7617 -- active set of scopes.
7619 for J
in reverse 0 .. Scope_Stack
.Last
loop
7620 if Scope_Stack
.Table
(J
).Entity
= S
then
7624 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7625 -- cases where Standard_Standard appears in the middle of the active
7626 -- set of scopes. This affects the declaration and overriding of
7627 -- private inherited operations in instantiations of generic child
7630 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7636 -----------------------------
7637 -- Inherit_Renamed_Profile --
7638 -----------------------------
7640 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7647 if Ekind
(Old_S
) = E_Operator
then
7648 New_F
:= First_Formal
(New_S
);
7650 while Present
(New_F
) loop
7651 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7652 Next_Formal
(New_F
);
7655 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7658 New_F
:= First_Formal
(New_S
);
7659 Old_F
:= First_Formal
(Old_S
);
7661 while Present
(New_F
) loop
7662 New_T
:= Etype
(New_F
);
7663 Old_T
:= Etype
(Old_F
);
7665 -- If the new type is a renaming of the old one, as is the
7666 -- case for actuals in instances, retain its name, to simplify
7667 -- later disambiguation.
7669 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7670 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7671 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7675 Set_Etype
(New_F
, Old_T
);
7678 Next_Formal
(New_F
);
7679 Next_Formal
(Old_F
);
7682 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7683 Set_Etype
(New_S
, Etype
(Old_S
));
7686 end Inherit_Renamed_Profile
;
7692 procedure Initialize
is
7697 -------------------------
7698 -- Install_Use_Clauses --
7699 -------------------------
7701 procedure Install_Use_Clauses
7703 Force_Installation
: Boolean := False)
7711 while Present
(U
) loop
7713 -- Case of USE package
7715 if Nkind
(U
) = N_Use_Package_Clause
then
7716 P
:= First
(Names
(U
));
7717 while Present
(P
) loop
7720 if Ekind
(Id
) = E_Package
then
7722 Note_Redundant_Use
(P
);
7724 elsif Present
(Renamed_Object
(Id
))
7725 and then In_Use
(Renamed_Object
(Id
))
7727 Note_Redundant_Use
(P
);
7729 elsif Force_Installation
or else Applicable_Use
(P
) then
7730 Use_One_Package
(Id
, U
);
7741 P
:= First
(Subtype_Marks
(U
));
7742 while Present
(P
) loop
7743 if not Is_Entity_Name
(P
)
7744 or else No
(Entity
(P
))
7748 elsif Entity
(P
) /= Any_Type
then
7756 Next_Use_Clause
(U
);
7758 end Install_Use_Clauses
;
7760 -------------------------------------
7761 -- Is_Appropriate_For_Entry_Prefix --
7762 -------------------------------------
7764 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7765 P_Type
: Entity_Id
:= T
;
7768 if Is_Access_Type
(P_Type
) then
7769 P_Type
:= Designated_Type
(P_Type
);
7772 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7773 end Is_Appropriate_For_Entry_Prefix
;
7775 -------------------------------
7776 -- Is_Appropriate_For_Record --
7777 -------------------------------
7779 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7781 function Has_Components
(T1
: Entity_Id
) return Boolean;
7782 -- Determine if given type has components (i.e. is either a record
7783 -- type or a type that has discriminants).
7785 --------------------
7786 -- Has_Components --
7787 --------------------
7789 function Has_Components
(T1
: Entity_Id
) return Boolean is
7791 return Is_Record_Type
(T1
)
7792 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7793 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7794 or else (Is_Incomplete_Type
(T1
)
7795 and then From_Limited_With
(T1
)
7796 and then Present
(Non_Limited_View
(T1
))
7797 and then Is_Record_Type
7798 (Get_Full_View
(Non_Limited_View
(T1
))));
7801 -- Start of processing for Is_Appropriate_For_Record
7806 and then (Has_Components
(T
)
7807 or else (Is_Access_Type
(T
)
7808 and then Has_Components
(Designated_Type
(T
))));
7809 end Is_Appropriate_For_Record
;
7811 ------------------------
7812 -- Note_Redundant_Use --
7813 ------------------------
7815 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7816 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7817 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7818 Decl
: constant Node_Id
:= Parent
(Clause
);
7820 Prev_Use
: Node_Id
:= Empty
;
7821 Redundant
: Node_Id
:= Empty
;
7822 -- The Use_Clause which is actually redundant. In the simplest case it
7823 -- is Pack itself, but when we compile a body we install its context
7824 -- before that of its spec, in which case it is the use_clause in the
7825 -- spec that will appear to be redundant, and we want the warning to be
7826 -- placed on the body. Similar complications appear when the redundancy
7827 -- is between a child unit and one of its ancestors.
7830 Set_Redundant_Use
(Clause
, True);
7832 if not Comes_From_Source
(Clause
)
7834 or else not Warn_On_Redundant_Constructs
7839 if not Is_Compilation_Unit
(Current_Scope
) then
7841 -- If the use_clause is in an inner scope, it is made redundant by
7842 -- some clause in the current context, with one exception: If we're
7843 -- compiling a nested package body, and the use_clause comes from the
7844 -- corresponding spec, the clause is not necessarily fully redundant,
7845 -- so we should not warn. If a warning was warranted, it would have
7846 -- been given when the spec was processed.
7848 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7850 Package_Spec_Entity
: constant Entity_Id
:=
7851 Defining_Unit_Name
(Parent
(Decl
));
7853 if In_Package_Body
(Package_Spec_Entity
) then
7859 Redundant
:= Clause
;
7860 Prev_Use
:= Cur_Use
;
7862 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7864 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7865 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7869 if Cur_Unit
= New_Unit
then
7871 -- Redundant clause in same body
7873 Redundant
:= Clause
;
7874 Prev_Use
:= Cur_Use
;
7876 elsif Cur_Unit
= Current_Sem_Unit
then
7878 -- If the new clause is not in the current unit it has been
7879 -- analyzed first, and it makes the other one redundant.
7880 -- However, if the new clause appears in a subunit, Cur_Unit
7881 -- is still the parent, and in that case the redundant one
7882 -- is the one appearing in the subunit.
7884 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7885 Redundant
:= Clause
;
7886 Prev_Use
:= Cur_Use
;
7888 -- Most common case: redundant clause in body,
7889 -- original clause in spec. Current scope is spec entity.
7894 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7896 Redundant
:= Cur_Use
;
7900 -- The new clause may appear in an unrelated unit, when
7901 -- the parents of a generic are being installed prior to
7902 -- instantiation. In this case there must be no warning.
7903 -- We detect this case by checking whether the current top
7904 -- of the stack is related to the current compilation.
7906 Scop
:= Current_Scope
;
7907 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7908 if Is_Compilation_Unit
(Scop
)
7909 and then not Is_Child_Unit
(Scop
)
7913 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7917 Scop
:= Scope
(Scop
);
7920 Redundant
:= Cur_Use
;
7924 elsif New_Unit
= Current_Sem_Unit
then
7925 Redundant
:= Clause
;
7926 Prev_Use
:= Cur_Use
;
7929 -- Neither is the current unit, so they appear in parent or
7930 -- sibling units. Warning will be emitted elsewhere.
7936 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
7937 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
7939 -- Use_clause is in child unit of current unit, and the child unit
7940 -- appears in the context of the body of the parent, so it has been
7941 -- installed first, even though it is the redundant one. Depending on
7942 -- their placement in the context, the visible or the private parts
7943 -- of the two units, either might appear as redundant, but the
7944 -- message has to be on the current unit.
7946 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
7947 Redundant
:= Cur_Use
;
7950 Redundant
:= Clause
;
7951 Prev_Use
:= Cur_Use
;
7954 -- If the new use clause appears in the private part of a parent unit
7955 -- it may appear to be redundant w.r.t. a use clause in a child unit,
7956 -- but the previous use clause was needed in the visible part of the
7957 -- child, and no warning should be emitted.
7959 if Nkind
(Parent
(Decl
)) = N_Package_Specification
7961 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
7964 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
7965 Spec
: constant Node_Id
:=
7966 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
7969 if Is_Compilation_Unit
(Par
)
7970 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
7971 and then Parent
(Cur_Use
) = Spec
7973 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
7980 -- Finally, if the current use clause is in the context then
7981 -- the clause is redundant when it is nested within the unit.
7983 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
7984 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
7985 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
7987 Redundant
:= Clause
;
7988 Prev_Use
:= Cur_Use
;
7994 if Present
(Redundant
) then
7995 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
7996 Error_Msg_NE
-- CODEFIX
7997 ("& is already use-visible through previous use clause #??",
7998 Redundant
, Pack_Name
);
8000 end Note_Redundant_Use
;
8006 procedure Pop_Scope
is
8007 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8008 S
: constant Entity_Id
:= SST
.Entity
;
8011 if Debug_Flag_E
then
8015 -- Set Default_Storage_Pool field of the library unit if necessary
8017 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8019 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8022 Aux
: constant Node_Id
:=
8023 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8025 if No
(Default_Storage_Pool
(Aux
)) then
8026 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8031 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8032 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8033 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8034 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8035 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8036 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8037 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8038 Default_SSO
:= SST
.Save_Default_SSO
;
8039 Uneval_Old
:= SST
.Save_Uneval_Old
;
8041 if Debug_Flag_W
then
8042 Write_Str
("<-- exiting scope: ");
8043 Write_Name
(Chars
(Current_Scope
));
8044 Write_Str
(", Depth=");
8045 Write_Int
(Int
(Scope_Stack
.Last
));
8049 End_Use_Clauses
(SST
.First_Use_Clause
);
8051 -- If the actions to be wrapped are still there they will get lost
8052 -- causing incomplete code to be generated. It is better to abort in
8053 -- this case (and we do the abort even with assertions off since the
8054 -- penalty is incorrect code generation).
8056 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8057 raise Program_Error;
8060 -- Free last subprogram name if allocated, and pop scope
8062 Free (SST.Last_Subprogram_Name);
8063 Scope_Stack.Decrement_Last;
8070 procedure Push_Scope (S : Entity_Id) is
8071 E : constant Entity_Id := Scope (S);
8074 if Ekind (S) = E_Void then
8077 -- Set scope depth if not a non-concurrent type, and we have not yet set
8078 -- the scope depth. This means that we have the first occurrence of the
8079 -- scope, and this is where the depth is set.
8081 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8082 and then not Scope_Depth_Set (S)
8084 if S = Standard_Standard then
8085 Set_Scope_Depth_Value (S, Uint_0);
8087 elsif Is_Child_Unit (S) then
8088 Set_Scope_Depth_Value (S, Uint_1);
8090 elsif not Is_Record_Type (Current_Scope) then
8091 if Ekind (S) = E_Loop then
8092 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8094 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8099 Scope_Stack.Increment_Last;
8102 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8106 SST.Save_Scope_Suppress := Scope_Suppress;
8107 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8108 SST.Save_Check_Policy_List := Check_Policy_List;
8109 SST.Save_Default_Storage_Pool := Default_Pool;
8110 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8111 SST.Save_SPARK_Mode := SPARK_Mode;
8112 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8113 SST.Save_Default_SSO := Default_SSO;
8114 SST.Save_Uneval_Old := Uneval_Old;
8116 if Scope_Stack.Last > Scope_Stack.First then
8117 SST.Component_Alignment_Default := Scope_Stack.Table
8118 (Scope_Stack.Last - 1).
8119 Component_Alignment_Default;
8122 SST.Last_Subprogram_Name := null;
8123 SST.Is_Transient := False;
8124 SST.Node_To_Be_Wrapped := Empty;
8125 SST.Pending_Freeze_Actions := No_List;
8126 SST.Actions_To_Be_Wrapped := (others => No_List);
8127 SST.First_Use_Clause := Empty;
8128 SST.Is_Active_Stack_Base := False;
8129 SST.Previous_Visibility := False;
8130 SST.Locked_Shared_Objects := No_Elist;
8133 if Debug_Flag_W then
8134 Write_Str ("--> new scope: ");
8135 Write_Name (Chars (Current_Scope));
8136 Write_Str (", Id=");
8137 Write_Int (Int (Current_Scope));
8138 Write_Str (", Depth=");
8139 Write_Int (Int (Scope_Stack.Last));
8143 -- Deal with copying flags from the previous scope to this one. This is
8144 -- not necessary if either scope is standard, or if the new scope is a
8147 if S /= Standard_Standard
8148 and then Scope (S) /= Standard_Standard
8149 and then not Is_Child_Unit (S)
8151 if Nkind (E) not in N_Entity then
8155 -- Copy categorization flags from Scope (S) to S, this is not done
8156 -- when Scope (S) is Standard_Standard since propagation is from
8157 -- library unit entity inwards. Copy other relevant attributes as
8158 -- well (Discard_Names in particular).
8160 -- We only propagate inwards for library level entities,
8161 -- inner level subprograms do not inherit the categorization.
8163 if Is_Library_Level_Entity (S) then
8164 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8165 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8166 Set_Discard_Names (S, Discard_Names (E));
8167 Set_Suppress_Value_Tracking_On_Call
8168 (S, Suppress_Value_Tracking_On_Call (E));
8169 Set_Categorization_From_Scope (E => S, Scop => E);
8173 if Is_Child_Unit (S)
8174 and then Present (E)
8175 and then Ekind_In (E, E_Package, E_Generic_Package)
8177 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8180 Aux : constant Node_Id :=
8181 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8183 if Present (Default_Storage_Pool (Aux)) then
8184 Default_Pool := Default_Storage_Pool (Aux);
8190 ---------------------
8191 -- Premature_Usage --
8192 ---------------------
8194 procedure Premature_Usage (N : Node_Id) is
8195 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8196 E : Entity_Id := Entity (N);
8199 -- Within an instance, the analysis of the actual for a formal object
8200 -- does not see the name of the object itself. This is significant only
8201 -- if the object is an aggregate, where its analysis does not do any
8202 -- name resolution on component associations. (see 4717-008). In such a
8203 -- case, look for the visible homonym on the chain.
8205 if In_Instance and then Present (Homonym (E)) then
8207 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8213 Set_Etype (N, Etype (E));
8218 if Kind = N_Component_Declaration then
8220 ("component&! cannot be used before end of record declaration", N);
8222 elsif Kind = N_Parameter_Specification then
8224 ("formal parameter&! cannot be used before end of specification",
8227 elsif Kind = N_Discriminant_Specification then
8229 ("discriminant&! cannot be used before end of discriminant part",
8232 elsif Kind = N_Procedure_Specification
8233 or else Kind = N_Function_Specification
8236 ("subprogram&! cannot be used before end of its declaration",
8239 elsif Kind = N_Full_Type_Declaration then
8241 ("type& cannot be used before end of its declaration!", N);
8245 ("object& cannot be used before end of its declaration!", N);
8247 end Premature_Usage;
8249 ------------------------
8250 -- Present_System_Aux --
8251 ------------------------
8253 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8255 Aux_Name : Unit_Name_Type;
8256 Unum : Unit_Number_Type;
8261 function Find_System (C_Unit : Node_Id) return Entity_Id;
8262 -- Scan context clause of compilation unit to find with_clause
8269 function Find_System (C_Unit : Node_Id) return Entity_Id is
8270 With_Clause : Node_Id;
8273 With_Clause := First (Context_Items (C_Unit));
8274 while Present (With_Clause) loop
8275 if (Nkind (With_Clause) = N_With_Clause
8276 and then Chars (Name (With_Clause)) = Name_System)
8277 and then Comes_From_Source (With_Clause)
8288 -- Start of processing for Present_System_Aux
8291 -- The child unit may have been loaded and analyzed already
8293 if Present (System_Aux_Id) then
8296 -- If no previous pragma for System.Aux, nothing to load
8298 elsif No (System_Extend_Unit) then
8301 -- Use the unit name given in the pragma to retrieve the unit.
8302 -- Verify that System itself appears in the context clause of the
8303 -- current compilation. If System is not present, an error will
8304 -- have been reported already.
8307 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8309 The_Unit := Unit (Cunit (Current_Sem_Unit));
8313 (Nkind (The_Unit) = N_Package_Body
8314 or else (Nkind (The_Unit) = N_Subprogram_Body
8315 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8317 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8320 if No (With_Sys) and then Present (N) then
8322 -- If we are compiling a subunit, we need to examine its
8323 -- context as well (Current_Sem_Unit is the parent unit);
8325 The_Unit := Parent (N);
8326 while Nkind (The_Unit) /= N_Compilation_Unit loop
8327 The_Unit := Parent (The_Unit);
8330 if Nkind (Unit (The_Unit)) = N_Subunit then
8331 With_Sys := Find_System (The_Unit);
8335 if No (With_Sys) then
8339 Loc := Sloc (With_Sys);
8340 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8341 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8342 Name_Buffer (1 .. 7) := "system.";
8343 Name_Buffer (Name_Len + 8) := '%';
8344 Name_Buffer (Name_Len + 9) := 's
';
8345 Name_Len := Name_Len + 9;
8346 Aux_Name := Name_Find;
8350 (Load_Name => Aux_Name,
8353 Error_Node => With_Sys);
8355 if Unum /= No_Unit then
8356 Semantics (Cunit (Unum));
8358 Defining_Entity (Specification (Unit (Cunit (Unum))));
8361 Make_With_Clause (Loc,
8363 Make_Expanded_Name (Loc,
8364 Chars => Chars (System_Aux_Id),
8365 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8366 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8368 Set_Entity (Name (Withn), System_Aux_Id);
8370 Set_Library_Unit (Withn, Cunit (Unum));
8371 Set_Corresponding_Spec (Withn, System_Aux_Id);
8372 Set_First_Name (Withn, True);
8373 Set_Implicit_With (Withn, True);
8375 Insert_After (With_Sys, Withn);
8376 Mark_Rewrite_Insertion (Withn);
8377 Set_Context_Installed (Withn);
8381 -- Here if unit load failed
8384 Error_Msg_Name_1 := Name_System;
8385 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8387 ("extension package `%.%` does not exist",
8388 Opt.System_Extend_Unit);
8392 end Present_System_Aux;
8394 -------------------------
8395 -- Restore_Scope_Stack --
8396 -------------------------
8398 procedure Restore_Scope_Stack
8400 Handle_Use : Boolean := True)
8402 SS_Last : constant Int := Scope_Stack.Last;
8406 -- Restore visibility of previous scope stack, if any, using the list
8407 -- we saved (we use Remove, since this list will not be used again).
8410 Elmt := Last_Elmt (List);
8411 exit when Elmt = No_Elmt;
8412 Set_Is_Immediately_Visible (Node (Elmt));
8413 Remove_Last_Elmt (List);
8416 -- Restore use clauses
8418 if SS_Last >= Scope_Stack.First
8419 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8422 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8424 end Restore_Scope_Stack;
8426 ----------------------
8427 -- Save_Scope_Stack --
8428 ----------------------
8430 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8431 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8432 -- from immediate visibility entities and Restore_Scope_Stack took care
8433 -- of restoring their visibility analyzing the context of each entity. The
8434 -- problem of such approach is that it was fragile and caused unexpected
8435 -- visibility problems, and indeed one test was found where there was a
8438 -- Furthermore, the following experiment was carried out:
8440 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8441 -- entities whose attribute Is_Immediately_Visible is modified
8442 -- from True to False.
8444 -- - Restore_Scope_Stack was modified to store in another Elist2
8445 -- all the entities whose attribute Is_Immediately_Visible is
8446 -- modified from False to True.
8448 -- - Extra code was added to verify that all the elements of Elist1
8449 -- are found in Elist2
8451 -- This test shows that there may be more occurrences of this problem which
8452 -- have not yet been detected. As a result, we replaced that approach by
8453 -- the current one in which Save_Scope_Stack returns the list of entities
8454 -- whose visibility is changed, and that list is passed to Restore_Scope_
8455 -- Stack to undo that change. This approach is simpler and safer, although
8456 -- it consumes more memory.
8458 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8459 Result : constant Elist_Id := New_Elmt_List;
8462 SS_Last : constant Int := Scope_Stack.Last;
8464 procedure Remove_From_Visibility (E : Entity_Id);
8465 -- If E is immediately visible then append it to the result and remove
8466 -- it temporarily from visibility.
8468 ----------------------------
8469 -- Remove_From_Visibility --
8470 ----------------------------
8472 procedure Remove_From_Visibility (E : Entity_Id) is
8474 if Is_Immediately_Visible (E) then
8475 Append_Elmt (E, Result);
8476 Set_Is_Immediately_Visible (E, False);
8478 end Remove_From_Visibility;
8480 -- Start of processing for Save_Scope_Stack
8483 if SS_Last >= Scope_Stack.First
8484 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8487 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8490 -- If the call is from within a compilation unit, as when called from
8491 -- Rtsfind, make current entries in scope stack invisible while we
8492 -- analyze the new unit.
8494 for J in reverse 0 .. SS_Last loop
8495 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8496 or else No (Scope_Stack.Table (J).Entity);
8498 S := Scope_Stack.Table (J).Entity;
8500 Remove_From_Visibility (S);
8502 E := First_Entity (S);
8503 while Present (E) loop
8504 Remove_From_Visibility (E);
8512 end Save_Scope_Stack;
8518 procedure Set_Use (L : List_Id) is
8520 Pack_Name : Node_Id;
8527 while Present (Decl) loop
8528 if Nkind (Decl) = N_Use_Package_Clause then
8529 Chain_Use_Clause (Decl);
8531 Pack_Name := First (Names (Decl));
8532 while Present (Pack_Name) loop
8533 Pack := Entity (Pack_Name);
8535 if Ekind (Pack) = E_Package
8536 and then Applicable_Use (Pack_Name)
8538 Use_One_Package (Pack, Decl);
8544 elsif Nkind (Decl) = N_Use_Type_Clause then
8545 Chain_Use_Clause (Decl);
8547 Id := First (Subtype_Marks (Decl));
8548 while Present (Id) loop
8549 if Entity (Id) /= Any_Type then
8562 ---------------------
8563 -- Use_One_Package --
8564 ---------------------
8566 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8569 Current_Instance : Entity_Id := Empty;
8571 Private_With_OK : Boolean := False;
8574 if Ekind (P) /= E_Package then
8579 Set_Current_Use_Clause (P, N);
8581 -- Ada 2005 (AI-50217): Check restriction
8583 if From_Limited_With (P) then
8584 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8587 -- Find enclosing instance, if any
8590 Current_Instance := Current_Scope;
8591 while not Is_Generic_Instance (Current_Instance) loop
8592 Current_Instance := Scope (Current_Instance);
8595 if No (Hidden_By_Use_Clause (N)) then
8596 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8600 -- If unit is a package renaming, indicate that the renamed
8601 -- package is also in use (the flags on both entities must
8602 -- remain consistent, and a subsequent use of either of them
8603 -- should be recognized as redundant).
8605 if Present (Renamed_Object (P)) then
8606 Set_In_Use (Renamed_Object (P));
8607 Set_Current_Use_Clause (Renamed_Object (P), N);
8608 Real_P := Renamed_Object (P);
8613 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8614 -- found in the private part of a package specification
8616 if In_Private_Part (Current_Scope)
8617 and then Has_Private_With (P)
8618 and then Is_Child_Unit (Current_Scope)
8619 and then Is_Child_Unit (P)
8620 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8622 Private_With_OK := True;
8625 -- Loop through entities in one package making them potentially
8628 Id := First_Entity (P);
8630 and then (Id /= First_Private_Entity (P)
8631 or else Private_With_OK) -- Ada 2005 (AI-262)
8633 Prev := Current_Entity (Id);
8634 while Present (Prev) loop
8635 if Is_Immediately_Visible (Prev)
8636 and then (not Is_Overloadable (Prev)
8637 or else not Is_Overloadable (Id)
8638 or else (Type_Conformant (Id, Prev)))
8640 if No (Current_Instance) then
8642 -- Potentially use-visible entity remains hidden
8644 goto Next_Usable_Entity;
8646 -- A use clause within an instance hides outer global entities,
8647 -- which are not used to resolve local entities in the
8648 -- instance. Note that the predefined entities in Standard
8649 -- could not have been hidden in the generic by a use clause,
8650 -- and therefore remain visible. Other compilation units whose
8651 -- entities appear in Standard must be hidden in an instance.
8653 -- To determine whether an entity is external to the instance
8654 -- we compare the scope depth of its scope with that of the
8655 -- current instance. However, a generic actual of a subprogram
8656 -- instance is declared in the wrapper package but will not be
8657 -- hidden by a use-visible entity. similarly, an entity that is
8658 -- declared in an enclosing instance will not be hidden by an
8659 -- an entity declared in a generic actual, which can only have
8660 -- been use-visible in the generic and will not have hidden the
8661 -- entity in the generic parent.
8663 -- If Id is called Standard, the predefined package with the
8664 -- same name is in the homonym chain. It has to be ignored
8665 -- because it has no defined scope (being the only entity in
8666 -- the system with this mandated behavior).
8668 elsif not Is_Hidden (Id)
8669 and then Present (Scope (Prev))
8670 and then not Is_Wrapper_Package (Scope (Prev))
8671 and then Scope_Depth (Scope (Prev)) <
8672 Scope_Depth (Current_Instance)
8673 and then (Scope (Prev) /= Standard_Standard
8674 or else Sloc (Prev) > Standard_Location)
8676 if In_Open_Scopes (Scope (Prev))
8677 and then Is_Generic_Instance (Scope (Prev))
8678 and then Present (Associated_Formal_Package (P))
8683 Set_Is_Potentially_Use_Visible (Id);
8684 Set_Is_Immediately_Visible (Prev, False);
8685 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8689 -- A user-defined operator is not use-visible if the predefined
8690 -- operator for the type is immediately visible, which is the case
8691 -- if the type of the operand is in an open scope. This does not
8692 -- apply to user-defined operators that have operands of different
8693 -- types, because the predefined mixed mode operations (multiply
8694 -- and divide) apply to universal types and do not hide anything.
8696 elsif Ekind (Prev) = E_Operator
8697 and then Operator_Matches_Spec (Prev, Id)
8698 and then In_Open_Scopes
8699 (Scope (Base_Type (Etype (First_Formal (Id)))))
8700 and then (No (Next_Formal (First_Formal (Id)))
8701 or else Etype (First_Formal (Id)) =
8702 Etype (Next_Formal (First_Formal (Id)))
8703 or else Chars (Prev) = Name_Op_Expon)
8705 goto Next_Usable_Entity;
8707 -- In an instance, two homonyms may become use_visible through the
8708 -- actuals of distinct formal packages. In the generic, only the
8709 -- current one would have been visible, so make the other one
8712 elsif Present (Current_Instance)
8713 and then Is_Potentially_Use_Visible (Prev)
8714 and then not Is_Overloadable (Prev)
8715 and then Scope (Id) /= Scope (Prev)
8716 and then Used_As_Generic_Actual (Scope (Prev))
8717 and then Used_As_Generic_Actual (Scope (Id))
8718 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8719 Current_Use_Clause (Scope (Id)))
8721 Set_Is_Potentially_Use_Visible (Prev, False);
8722 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8725 Prev := Homonym (Prev);
8728 -- On exit, we know entity is not hidden, unless it is private
8730 if not Is_Hidden (Id)
8731 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8733 Set_Is_Potentially_Use_Visible (Id);
8735 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8736 Set_Is_Potentially_Use_Visible (Full_View (Id));
8740 <<Next_Usable_Entity>>
8744 -- Child units are also made use-visible by a use clause, but they may
8745 -- appear after all visible declarations in the parent entity list.
8747 while Present (Id) loop
8748 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8749 Set_Is_Potentially_Use_Visible (Id);
8755 if Chars (Real_P) = Name_System
8756 and then Scope (Real_P) = Standard_Standard
8757 and then Present_System_Aux (N)
8759 Use_One_Package (System_Aux_Id, N);
8762 end Use_One_Package;
8768 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8770 Is_Known_Used : Boolean;
8774 function Spec_Reloaded_For_Body return Boolean;
8775 -- Determine whether the compilation unit is a package body and the use
8776 -- type clause is in the spec of the same package. Even though the spec
8777 -- was analyzed first, its context is reloaded when analysing the body.
8779 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8780 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8781 -- class-wide operations of ancestor types are use-visible if the
8782 -- ancestor type is visible.
8784 ----------------------------
8785 -- Spec_Reloaded_For_Body --
8786 ----------------------------
8788 function Spec_Reloaded_For_Body return Boolean is
8790 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8792 Spec : constant Node_Id :=
8793 Parent (List_Containing (Parent (Id)));
8796 -- Check whether type is declared in a package specification,
8797 -- and current unit is the corresponding package body. The
8798 -- use clauses themselves may be within a nested package.
8801 Nkind (Spec) = N_Package_Specification
8803 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8804 Cunit_Entity (Current_Sem_Unit));
8809 end Spec_Reloaded_For_Body;
8811 -------------------------------
8812 -- Use_Class_Wide_Operations --
8813 -------------------------------
8815 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8819 function Is_Class_Wide_Operation_Of
8821 T : Entity_Id) return Boolean;
8822 -- Determine whether a subprogram has a class-wide parameter or
8823 -- result that is T'Class.
8825 ---------------------------------
8826 -- Is_Class_Wide_Operation_Of --
8827 ---------------------------------
8829 function Is_Class_Wide_Operation_Of
8831 T : Entity_Id) return Boolean
8836 Formal := First_Formal (Op);
8837 while Present (Formal) loop
8838 if Etype (Formal) = Class_Wide_Type (T) then
8841 Next_Formal (Formal);
8844 if Etype (Op) = Class_Wide_Type (T) then
8849 end Is_Class_Wide_Operation_Of;
8851 -- Start of processing for Use_Class_Wide_Operations
8854 Scop := Scope (Typ);
8855 if not Is_Hidden (Scop) then
8856 Ent := First_Entity (Scop);
8857 while Present (Ent) loop
8858 if Is_Overloadable (Ent)
8859 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8860 and then not Is_Potentially_Use_Visible (Ent)
8862 Set_Is_Potentially_Use_Visible (Ent);
8863 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8870 if Is_Derived_Type (Typ) then
8871 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8873 end Use_Class_Wide_Operations;
8875 -- Start of processing for Use_One_Type
8878 -- It is the type determined by the subtype mark (8.4(8)) whose
8879 -- operations become potentially use-visible.
8881 T := Base_Type (Entity (Id));
8883 -- Either the type itself is used, the package where it is declared
8884 -- is in use or the entity is declared in the current package, thus
8889 or else In_Use (Scope (T))
8890 or else Scope (T) = Current_Scope;
8892 Set_Redundant_Use (Id,
8893 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8895 if Ekind (T) = E_Incomplete_Type then
8896 Error_Msg_N ("premature usage of incomplete type", Id);
8898 elsif In_Open_Scopes (Scope (T)) then
8901 -- A limited view cannot appear in a use_type clause. However, an access
8902 -- type whose designated type is limited has the flag but is not itself
8903 -- a limited view unless we only have a limited view of its enclosing
8906 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8908 ("incomplete type from limited view "
8909 & "cannot appear in use clause", Id);
8911 -- If the subtype mark designates a subtype in a different package,
8912 -- we have to check that the parent type is visible, otherwise the
8913 -- use type clause is a noop. Not clear how to do that???
8915 elsif not Redundant_Use (Id) then
8918 -- If T is tagged, primitive operators on class-wide operands
8919 -- are also available.
8921 if Is_Tagged_Type (T) then
8922 Set_In_Use (Class_Wide_Type (T));
8925 Set_Current_Use_Clause (T, Parent (Id));
8927 -- Iterate over primitive operations of the type. If an operation is
8928 -- already use_visible, it is the result of a previous use_clause,
8929 -- and already appears on the corresponding entity chain. If the
8930 -- clause is being reinstalled, operations are already use-visible.
8936 Op_List := Collect_Primitive_Operations (T);
8937 Elmt := First_Elmt (Op_List);
8938 while Present (Elmt) loop
8939 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
8940 or else Chars (Node (Elmt)) in Any_Operator_Name)
8941 and then not Is_Hidden (Node (Elmt))
8942 and then not Is_Potentially_Use_Visible (Node (Elmt))
8944 Set_Is_Potentially_Use_Visible (Node (Elmt));
8945 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8947 elsif Ada_Version >= Ada_2012
8948 and then All_Present (Parent (Id))
8949 and then not Is_Hidden (Node (Elmt))
8950 and then not Is_Potentially_Use_Visible (Node (Elmt))
8952 Set_Is_Potentially_Use_Visible (Node (Elmt));
8953 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
8960 if Ada_Version >= Ada_2012
8961 and then All_Present (Parent (Id))
8962 and then Is_Tagged_Type (T)
8964 Use_Class_Wide_Operations (T);
8968 -- If warning on redundant constructs, check for unnecessary WITH
8970 if Warn_On_Redundant_Constructs
8971 and then Is_Known_Used
8973 -- with P; with P; use P;
8974 -- package P is package X is package body X is
8975 -- type T ... use P.T;
8977 -- The compilation unit is the body of X. GNAT first compiles the
8978 -- spec of X, then proceeds to the body. At that point P is marked
8979 -- as use visible. The analysis then reinstalls the spec along with
8980 -- its context. The use clause P.T is now recognized as redundant,
8981 -- but in the wrong context. Do not emit a warning in such cases.
8982 -- Do not emit a warning either if we are in an instance, there is
8983 -- no redundancy between an outer use_clause and one that appears
8984 -- within the generic.
8986 and then not Spec_Reloaded_For_Body
8987 and then not In_Instance
8989 -- The type already has a use clause
8993 -- Case where we know the current use clause for the type
8995 if Present (Current_Use_Clause (T)) then
8996 Use_Clause_Known : declare
8997 Clause1 : constant Node_Id := Parent (Id);
8998 Clause2 : constant Node_Id := Current_Use_Clause (T);
9005 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9006 -- Return the appropriate entity for determining which unit
9007 -- has a deeper scope: the defining entity for U, unless U
9008 -- is a package instance, in which case we retrieve the
9009 -- entity of the instance spec.
9011 --------------------
9012 -- Entity_Of_Unit --
9013 --------------------
9015 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9017 if Nkind (U) = N_Package_Instantiation
9018 and then Analyzed (U)
9020 return Defining_Entity (Instance_Spec (U));
9022 return Defining_Entity (U);
9026 -- Start of processing for Use_Clause_Known
9029 -- If both current use type clause and the use type clause
9030 -- for the type are at the compilation unit level, one of
9031 -- the units must be an ancestor of the other, and the
9032 -- warning belongs on the descendant.
9034 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9036 Nkind (Parent (Clause2)) = N_Compilation_Unit
9038 -- If the unit is a subprogram body that acts as spec,
9039 -- the context clause is shared with the constructed
9040 -- subprogram spec. Clearly there is no redundancy.
9042 if Clause1 = Clause2 then
9046 Unit1 := Unit (Parent (Clause1));
9047 Unit2 := Unit (Parent (Clause2));
9049 -- If both clauses are on same unit, or one is the body
9050 -- of the other, or one of them is in a subunit, report
9051 -- redundancy on the later one.
9053 if Unit1 = Unit2 then
9054 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9055 Error_Msg_NE -- CODEFIX
9056 ("& is already use-visible through previous "
9057 & "use_type_clause #??", Clause1, T);
9060 elsif Nkind (Unit1) = N_Subunit then
9061 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9062 Error_Msg_NE -- CODEFIX
9063 ("& is already use-visible through previous "
9064 & "use_type_clause #??", Clause1, T);
9067 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9068 and then Nkind (Unit1) /= Nkind (Unit2)
9069 and then Nkind (Unit1) /= N_Subunit
9071 Error_Msg_Sloc := Sloc (Clause1);
9072 Error_Msg_NE -- CODEFIX
9073 ("& is already use-visible through previous "
9074 & "use_type_clause #??", Current_Use_Clause (T), T);
9078 -- There is a redundant use type clause in a child unit.
9079 -- Determine which of the units is more deeply nested.
9080 -- If a unit is a package instance, retrieve the entity
9081 -- and its scope from the instance spec.
9083 Ent1 := Entity_Of_Unit (Unit1);
9084 Ent2 := Entity_Of_Unit (Unit2);
9086 if Scope (Ent2) = Standard_Standard then
9087 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9090 elsif Scope (Ent1) = Standard_Standard then
9091 Error_Msg_Sloc := Sloc (Id);
9094 -- If both units are child units, we determine which one
9095 -- is the descendant by the scope distance to the
9096 -- ultimate parent unit.
9106 and then Present (S2)
9107 and then S1 /= Standard_Standard
9108 and then S2 /= Standard_Standard
9114 if S1 = Standard_Standard then
9115 Error_Msg_Sloc := Sloc (Id);
9118 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9124 Error_Msg_NE -- CODEFIX
9125 ("& is already use-visible through previous "
9126 & "use_type_clause #??", Err_No, Id);
9128 -- Case where current use type clause and the use type
9129 -- clause for the type are not both at the compilation unit
9130 -- level. In this case we don't have location information.
9133 Error_Msg_NE -- CODEFIX
9134 ("& is already use-visible through previous "
9135 & "use type clause??", Id, T);
9137 end Use_Clause_Known;
9139 -- Here if Current_Use_Clause is not set for T, another case
9140 -- where we do not have the location information available.
9143 Error_Msg_NE -- CODEFIX
9144 ("& is already use-visible through previous "
9145 & "use type clause??", Id, T);
9148 -- The package where T is declared is already used
9150 elsif In_Use (Scope (T)) then
9151 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9152 Error_Msg_NE -- CODEFIX
9153 ("& is already use-visible through package use clause #??",
9156 -- The current scope is the package where T is declared
9159 Error_Msg_Node_2 := Scope (T);
9160 Error_Msg_NE -- CODEFIX
9161 ("& is already use-visible inside package &??", Id, T);
9170 procedure Write_Info is
9171 Id : Entity_Id := First_Entity (Current_Scope);
9174 -- No point in dumping standard entities
9176 if Current_Scope = Standard_Standard then
9180 Write_Str ("========================================================");
9182 Write_Str (" Defined Entities in ");
9183 Write_Name (Chars (Current_Scope));
9185 Write_Str ("========================================================");
9189 Write_Str ("-- none --");
9193 while Present (Id) loop
9194 Write_Entity_Info (Id, " ");
9199 if Scope (Current_Scope) = Standard_Standard then
9201 -- Print information on the current unit itself
9203 Write_Entity_Info (Current_Scope, " ");
9216 for J in reverse 1 .. Scope_Stack.Last loop
9217 S := Scope_Stack.Table (J).Entity;
9218 Write_Int (Int (S));
9219 Write_Str (" === ");
9220 Write_Name (Chars (S));
9229 procedure we (S : Entity_Id) is
9232 E := First_Entity (S);
9233 while Present (E) loop
9234 Write_Int (Int (E));
9235 Write_Str (" === ");
9236 Write_Name (Chars (E));