1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Tss
; use Exp_Tss
;
32 with Exp_Util
; use Exp_Util
;
33 with Fname
; use Fname
;
34 with Freeze
; use Freeze
;
35 with Impunit
; use Impunit
;
37 with Lib
.Load
; use Lib
.Load
;
38 with Lib
.Xref
; use Lib
.Xref
;
39 with Namet
; use Namet
;
40 with Namet
.Sp
; use Namet
.Sp
;
41 with Nlists
; use Nlists
;
42 with Nmake
; use Nmake
;
44 with Output
; use Output
;
45 with Restrict
; use Restrict
;
46 with Rident
; use Rident
;
47 with Rtsfind
; use Rtsfind
;
49 with Sem_Aux
; use Sem_Aux
;
50 with Sem_Cat
; use Sem_Cat
;
51 with Sem_Ch3
; use Sem_Ch3
;
52 with Sem_Ch4
; use Sem_Ch4
;
53 with Sem_Ch6
; use Sem_Ch6
;
54 with Sem_Ch12
; use Sem_Ch12
;
55 with Sem_Disp
; use Sem_Disp
;
56 with Sem_Dist
; use Sem_Dist
;
57 with Sem_Eval
; use Sem_Eval
;
58 with Sem_Res
; use Sem_Res
;
59 with Sem_Util
; use Sem_Util
;
60 with Sem_Type
; use Sem_Type
;
61 with Stand
; use Stand
;
62 with Sinfo
; use Sinfo
;
63 with Sinfo
.CN
; use Sinfo
.CN
;
64 with Snames
; use Snames
;
65 with Style
; use Style
;
67 with Tbuild
; use Tbuild
;
68 with Uintp
; use Uintp
;
70 package body Sem_Ch8
is
72 ------------------------------------
73 -- Visibility and Name Resolution --
74 ------------------------------------
76 -- This package handles name resolution and the collection of
77 -- interpretations for overloaded names, prior to overload resolution.
79 -- Name resolution is the process that establishes a mapping between source
80 -- identifiers and the entities they denote at each point in the program.
81 -- Each entity is represented by a defining occurrence. Each identifier
82 -- that denotes an entity points to the corresponding defining occurrence.
83 -- This is the entity of the applied occurrence. Each occurrence holds
84 -- an index into the names table, where source identifiers are stored.
86 -- Each entry in the names table for an identifier or designator uses the
87 -- Info pointer to hold a link to the currently visible entity that has
88 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
89 -- in package Sem_Util). The visibility is initialized at the beginning of
90 -- semantic processing to make entities in package Standard immediately
91 -- visible. The visibility table is used in a more subtle way when
92 -- compiling subunits (see below).
94 -- Entities that have the same name (i.e. homonyms) are chained. In the
95 -- case of overloaded entities, this chain holds all the possible meanings
96 -- of a given identifier. The process of overload resolution uses type
97 -- information to select from this chain the unique meaning of a given
100 -- Entities are also chained in their scope, through the Next_Entity link.
101 -- As a consequence, the name space is organized as a sparse matrix, where
102 -- each row corresponds to a scope, and each column to a source identifier.
103 -- Open scopes, that is to say scopes currently being compiled, have their
104 -- corresponding rows of entities in order, innermost scope first.
106 -- The scopes of packages that are mentioned in context clauses appear in
107 -- no particular order, interspersed among open scopes. This is because
108 -- in the course of analyzing the context of a compilation, a package
109 -- declaration is first an open scope, and subsequently an element of the
110 -- context. If subunits or child units are present, a parent unit may
111 -- appear under various guises at various times in the compilation.
113 -- When the compilation of the innermost scope is complete, the entities
114 -- defined therein are no longer visible. If the scope is not a package
115 -- declaration, these entities are never visible subsequently, and can be
116 -- removed from visibility chains. If the scope is a package declaration,
117 -- its visible declarations may still be accessible. Therefore the entities
118 -- defined in such a scope are left on the visibility chains, and only
119 -- their visibility (immediately visibility or potential use-visibility)
122 -- The ordering of homonyms on their chain does not necessarily follow
123 -- the order of their corresponding scopes on the scope stack. For
124 -- example, if package P and the enclosing scope both contain entities
125 -- named E, then when compiling the package body the chain for E will
126 -- hold the global entity first, and the local one (corresponding to
127 -- the current inner scope) next. As a result, name resolution routines
128 -- do not assume any relative ordering of the homonym chains, either
129 -- for scope nesting or to order of appearance of context clauses.
131 -- When compiling a child unit, entities in the parent scope are always
132 -- immediately visible. When compiling the body of a child unit, private
133 -- entities in the parent must also be made immediately visible. There
134 -- are separate routines to make the visible and private declarations
135 -- visible at various times (see package Sem_Ch7).
137 -- +--------+ +-----+
138 -- | In use |-------->| EU1 |-------------------------->
139 -- +--------+ +-----+
141 -- +--------+ +-----+ +-----+
142 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
143 -- +--------+ +-----+ +-----+
145 -- +---------+ | +-----+
146 -- | with'ed |------------------------------>| EW2 |--->
147 -- +---------+ | +-----+
149 -- +--------+ +-----+ +-----+
150 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
151 -- +--------+ +-----+ +-----+
153 -- +--------+ +-----+ +-----+
154 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
155 -- +--------+ +-----+ +-----+
159 -- | | with'ed |----------------------------------------->
163 -- (innermost first) | |
164 -- +----------------------------+
165 -- Names table => | Id1 | | | | Id2 |
166 -- +----------------------------+
168 -- Name resolution must deal with several syntactic forms: simple names,
169 -- qualified names, indexed names, and various forms of calls.
171 -- Each identifier points to an entry in the names table. The resolution
172 -- of a simple name consists in traversing the homonym chain, starting
173 -- from the names table. If an entry is immediately visible, it is the one
174 -- designated by the identifier. If only potentially use-visible entities
175 -- are on the chain, we must verify that they do not hide each other. If
176 -- the entity we find is overloadable, we collect all other overloadable
177 -- entities on the chain as long as they are not hidden.
179 -- To resolve expanded names, we must find the entity at the intersection
180 -- of the entity chain for the scope (the prefix) and the homonym chain
181 -- for the selector. In general, homonym chains will be much shorter than
182 -- entity chains, so it is preferable to start from the names table as
183 -- well. If the entity found is overloadable, we must collect all other
184 -- interpretations that are defined in the scope denoted by the prefix.
186 -- For records, protected types, and tasks, their local entities are
187 -- removed from visibility chains on exit from the corresponding scope.
188 -- From the outside, these entities are always accessed by selected
189 -- notation, and the entity chain for the record type, protected type,
190 -- etc. is traversed sequentially in order to find the designated entity.
192 -- The discriminants of a type and the operations of a protected type or
193 -- task are unchained on exit from the first view of the type, (such as
194 -- a private or incomplete type declaration, or a protected type speci-
195 -- fication) and re-chained when compiling the second view.
197 -- In the case of operators, we do not make operators on derived types
198 -- explicit. As a result, the notation P."+" may denote either a user-
199 -- defined function with name "+", or else an implicit declaration of the
200 -- operator "+" in package P. The resolution of expanded names always
201 -- tries to resolve an operator name as such an implicitly defined entity,
202 -- in addition to looking for explicit declarations.
204 -- All forms of names that denote entities (simple names, expanded names,
205 -- character literals in some cases) have a Entity attribute, which
206 -- identifies the entity denoted by the name.
208 ---------------------
209 -- The Scope Stack --
210 ---------------------
212 -- The Scope stack keeps track of the scopes currently been compiled.
213 -- Every entity that contains declarations (including records) is placed
214 -- on the scope stack while it is being processed, and removed at the end.
215 -- Whenever a non-package scope is exited, the entities defined therein
216 -- are removed from the visibility table, so that entities in outer scopes
217 -- become visible (see previous description). On entry to Sem, the scope
218 -- stack only contains the package Standard. As usual, subunits complicate
219 -- this picture ever so slightly.
221 -- The Rtsfind mechanism can force a call to Semantics while another
222 -- compilation is in progress. The unit retrieved by Rtsfind must be
223 -- compiled in its own context, and has no access to the visibility of
224 -- the unit currently being compiled. The procedures Save_Scope_Stack and
225 -- Restore_Scope_Stack make entities in current open scopes invisible
226 -- before compiling the retrieved unit, and restore the compilation
227 -- environment afterwards.
229 ------------------------
230 -- Compiling subunits --
231 ------------------------
233 -- Subunits must be compiled in the environment of the corresponding stub,
234 -- that is to say with the same visibility into the parent (and its
235 -- context) that is available at the point of the stub declaration, but
236 -- with the additional visibility provided by the context clause of the
237 -- subunit itself. As a result, compilation of a subunit forces compilation
238 -- of the parent (see description in lib-). At the point of the stub
239 -- declaration, Analyze is called recursively to compile the proper body of
240 -- the subunit, but without reinitializing the names table, nor the scope
241 -- stack (i.e. standard is not pushed on the stack). In this fashion the
242 -- context of the subunit is added to the context of the parent, and the
243 -- subunit is compiled in the correct environment. Note that in the course
244 -- of processing the context of a subunit, Standard will appear twice on
245 -- the scope stack: once for the parent of the subunit, and once for the
246 -- unit in the context clause being compiled. However, the two sets of
247 -- entities are not linked by homonym chains, so that the compilation of
248 -- any context unit happens in a fresh visibility environment.
250 -------------------------------
251 -- Processing of USE Clauses --
252 -------------------------------
254 -- Every defining occurrence has a flag indicating if it is potentially use
255 -- visible. Resolution of simple names examines this flag. The processing
256 -- of use clauses consists in setting this flag on all visible entities
257 -- defined in the corresponding package. On exit from the scope of the use
258 -- clause, the corresponding flag must be reset. However, a package may
259 -- appear in several nested use clauses (pathological but legal, alas!)
260 -- which forces us to use a slightly more involved scheme:
262 -- a) The defining occurrence for a package holds a flag -In_Use- to
263 -- indicate that it is currently in the scope of a use clause. If a
264 -- redundant use clause is encountered, then the corresponding occurrence
265 -- of the package name is flagged -Redundant_Use-.
267 -- b) On exit from a scope, the use clauses in its declarative part are
268 -- scanned. The visibility flag is reset in all entities declared in
269 -- package named in a use clause, as long as the package is not flagged
270 -- as being in a redundant use clause (in which case the outer use
271 -- clause is still in effect, and the direct visibility of its entities
272 -- must be retained).
274 -- Note that entities are not removed from their homonym chains on exit
275 -- from the package specification. A subsequent use clause does not need
276 -- to rechain the visible entities, but only to establish their direct
279 -----------------------------------
280 -- Handling private declarations --
281 -----------------------------------
283 -- The principle that each entity has a single defining occurrence clashes
284 -- with the presence of two separate definitions for private types: the
285 -- first is the private type declaration, and second is the full type
286 -- declaration. It is important that all references to the type point to
287 -- the same defining occurrence, namely the first one. To enforce the two
288 -- separate views of the entity, the corresponding information is swapped
289 -- between the two declarations. Outside of the package, the defining
290 -- occurrence only contains the private declaration information, while in
291 -- the private part and the body of the package the defining occurrence
292 -- contains the full declaration. To simplify the swap, the defining
293 -- occurrence that currently holds the private declaration points to the
294 -- full declaration. During semantic processing the defining occurrence
295 -- also points to a list of private dependents, that is to say access types
296 -- or composite types whose designated types or component types are
297 -- subtypes or derived types of the private type in question. After the
298 -- full declaration has been seen, the private dependents are updated to
299 -- indicate that they have full definitions.
301 ------------------------------------
302 -- Handling of Undefined Messages --
303 ------------------------------------
305 -- In normal mode, only the first use of an undefined identifier generates
306 -- a message. The table Urefs is used to record error messages that have
307 -- been issued so that second and subsequent ones do not generate further
308 -- messages. However, the second reference causes text to be added to the
309 -- original undefined message noting "(more references follow)". The
310 -- full error list option (-gnatf) forces messages to be generated for
311 -- every reference and disconnects the use of this table.
313 type Uref_Entry
is record
315 -- Node for identifier for which original message was posted. The
316 -- Chars field of this identifier is used to detect later references
317 -- to the same identifier.
320 -- Records error message Id of original undefined message. Reset to
321 -- No_Error_Msg after the second occurrence, where it is used to add
322 -- text to the original message as described above.
325 -- Set if the message is not visible rather than undefined
328 -- Records location of error message. Used to make sure that we do
329 -- not consider a, b : undefined as two separate instances, which
330 -- would otherwise happen, since the parser converts this sequence
331 -- to a : undefined; b : undefined.
335 package Urefs
is new Table
.Table
(
336 Table_Component_Type
=> Uref_Entry
,
337 Table_Index_Type
=> Nat
,
338 Table_Low_Bound
=> 1,
340 Table_Increment
=> 100,
341 Table_Name
=> "Urefs");
343 Candidate_Renaming
: Entity_Id
;
344 -- Holds a candidate interpretation that appears in a subprogram renaming
345 -- declaration and does not match the given specification, but matches at
346 -- least on the first formal. Allows better error message when given
347 -- specification omits defaulted parameters, a common error.
349 -----------------------
350 -- Local Subprograms --
351 -----------------------
353 procedure Analyze_Generic_Renaming
356 -- Common processing for all three kinds of generic renaming declarations.
357 -- Enter new name and indicate that it renames the generic unit.
359 procedure Analyze_Renamed_Character
363 -- Renamed entity is given by a character literal, which must belong
364 -- to the return type of the new entity. Is_Body indicates whether the
365 -- declaration is a renaming_as_body. If the original declaration has
366 -- already been frozen (because of an intervening body, e.g.) the body of
367 -- the function must be built now. The same applies to the following
368 -- various renaming procedures.
370 procedure Analyze_Renamed_Dereference
374 -- Renamed entity is given by an explicit dereference. Prefix must be a
375 -- conformant access_to_subprogram type.
377 procedure Analyze_Renamed_Entry
381 -- If the renamed entity in a subprogram renaming is an entry or protected
382 -- subprogram, build a body for the new entity whose only statement is a
383 -- call to the renamed entity.
385 procedure Analyze_Renamed_Family_Member
389 -- Used when the renamed entity is an indexed component. The prefix must
390 -- denote an entry family.
392 procedure Analyze_Renamed_Primitive_Operation
396 -- If the renamed entity in a subprogram renaming is a primitive operation
397 -- or a class-wide operation in prefix form, save the target object, which
398 -- must be added to the list of actuals in any subsequent call.
400 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
401 -- Common code to Use_One_Package and Set_Use, to determine whether use
402 -- clause must be processed. Pack_Name is an entity name that references
403 -- the package in question.
405 procedure Attribute_Renaming
(N
: Node_Id
);
406 -- Analyze renaming of attribute as subprogram. The renaming declaration N
407 -- is rewritten as a subprogram body that returns the attribute reference
408 -- applied to the formals of the function.
410 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
411 -- Set Entity, with style check if need be. For a discriminant reference,
412 -- replace by the corresponding discriminal, i.e. the parameter of the
413 -- initialization procedure that corresponds to the discriminant.
415 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
416 -- A renaming_as_body may occur after the entity of the original decla-
417 -- ration has been frozen. In that case, the body of the new entity must
418 -- be built now, because the usual mechanism of building the renamed
419 -- body at the point of freezing will not work. Subp is the subprogram
420 -- for which N provides the Renaming_As_Body.
422 procedure Check_In_Previous_With_Clause
425 -- N is a use_package clause and Nam the package name, or N is a use_type
426 -- clause and Nam is the prefix of the type name. In either case, verify
427 -- that the package is visible at that point in the context: either it
428 -- appears in a previous with_clause, or because it is a fully qualified
429 -- name and the root ancestor appears in a previous with_clause.
431 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
432 -- Verify that the entity in a renaming declaration that is a library unit
433 -- is itself a library unit and not a nested unit or subunit. Also check
434 -- that if the renaming is a child unit of a generic parent, then the
435 -- renamed unit must also be a child unit of that parent. Finally, verify
436 -- that a renamed generic unit is not an implicit child declared within
437 -- an instance of the parent.
439 procedure Chain_Use_Clause
(N
: Node_Id
);
440 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
441 -- the proper scope table entry. This is usually the current scope, but it
442 -- will be an inner scope when installing the use clauses of the private
443 -- declarations of a parent unit prior to compiling the private part of a
444 -- child unit. This chain is traversed when installing/removing use clauses
445 -- when compiling a subunit or instantiating a generic body on the fly,
446 -- when it is necessary to save and restore full environments.
448 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
449 -- Find a type derived from Character or Wide_Character in the prefix of N.
450 -- Used to resolved qualified names whose selector is a character literal.
452 function Has_Private_With
(E
: Entity_Id
) return Boolean;
453 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
454 -- private with on E.
456 procedure Find_Expanded_Name
(N
: Node_Id
);
457 -- The input is a selected component is known to be expanded name. Verify
458 -- legality of selector given the scope denoted by prefix, and change node
459 -- N into a expanded name with a properly set Entity field.
461 function Find_Renamed_Entity
465 Is_Actual
: Boolean := False) return Entity_Id
;
466 -- Find the renamed entity that corresponds to the given parameter profile
467 -- in a subprogram renaming declaration. The renamed entity may be an
468 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
469 -- indicates that the renaming is the one generated for an actual subpro-
470 -- gram in an instance, for which special visibility checks apply.
472 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
473 -- N is an expanded name whose selector is an operator name (e.g. P."+").
474 -- declarative part contains an implicit declaration of an operator if it
475 -- has a declaration of a type to which one of the predefined operators
476 -- apply. The existence of this routine is an implementation artifact. A
477 -- more straightforward but more space-consuming choice would be to make
478 -- all inherited operators explicit in the symbol table.
480 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
481 -- A subprogram defined by a renaming declaration inherits the parameter
482 -- profile of the renamed entity. The subtypes given in the subprogram
483 -- specification are discarded and replaced with those of the renamed
484 -- subprogram, which are then used to recheck the default values.
486 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
487 -- Prefix is appropriate for record if it is of a record type, or an access
490 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
491 -- True if it is of a task type, a protected type, or else an access to one
494 procedure Note_Redundant_Use
(Clause
: Node_Id
);
495 -- Mark the name in a use clause as redundant if the corresponding entity
496 -- is already use-visible. Emit a warning if the use clause comes from
497 -- source and the proper warnings are enabled.
499 procedure Premature_Usage
(N
: Node_Id
);
500 -- Diagnose usage of an entity before it is visible
502 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
503 -- Make visible entities declared in package P potentially use-visible
504 -- in the current context. Also used in the analysis of subunits, when
505 -- re-installing use clauses of parent units. N is the use_clause that
506 -- names P (and possibly other packages).
508 procedure Use_One_Type
(Id
: Node_Id
);
509 -- Id is the subtype mark from a use type clause. This procedure makes
510 -- the primitive operators of the type potentially use-visible.
512 procedure Write_Info
;
513 -- Write debugging information on entities declared in current scope
515 --------------------------------
516 -- Analyze_Exception_Renaming --
517 --------------------------------
519 -- The language only allows a single identifier, but the tree holds an
520 -- identifier list. The parser has already issued an error message if
521 -- there is more than one element in the list.
523 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
524 Id
: constant Node_Id
:= Defining_Identifier
(N
);
525 Nam
: constant Node_Id
:= Name
(N
);
531 Set_Ekind
(Id
, E_Exception
);
532 Set_Exception_Code
(Id
, Uint_0
);
533 Set_Etype
(Id
, Standard_Exception_Type
);
534 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
536 if not Is_Entity_Name
(Nam
) or else
537 Ekind
(Entity
(Nam
)) /= E_Exception
539 Error_Msg_N
("invalid exception name in renaming", Nam
);
541 if Present
(Renamed_Object
(Entity
(Nam
))) then
542 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
544 Set_Renamed_Object
(Id
, Entity
(Nam
));
547 end Analyze_Exception_Renaming
;
549 ---------------------------
550 -- Analyze_Expanded_Name --
551 ---------------------------
553 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
555 -- If the entity pointer is already set, this is an internal node, or a
556 -- node that is analyzed more than once, after a tree modification. In
557 -- such a case there is no resolution to perform, just set the type. For
558 -- completeness, analyze prefix as well.
560 if Present
(Entity
(N
)) then
561 if Is_Type
(Entity
(N
)) then
562 Set_Etype
(N
, Entity
(N
));
564 Set_Etype
(N
, Etype
(Entity
(N
)));
567 Analyze
(Prefix
(N
));
570 Find_Expanded_Name
(N
);
572 end Analyze_Expanded_Name
;
574 ---------------------------------------
575 -- Analyze_Generic_Function_Renaming --
576 ---------------------------------------
578 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
580 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
581 end Analyze_Generic_Function_Renaming
;
583 --------------------------------------
584 -- Analyze_Generic_Package_Renaming --
585 --------------------------------------
587 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
589 -- Apply the Text_IO Kludge here, since we may be renaming one of the
590 -- subpackages of Text_IO, then join common routine.
592 Text_IO_Kludge
(Name
(N
));
594 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
595 end Analyze_Generic_Package_Renaming
;
597 ----------------------------------------
598 -- Analyze_Generic_Procedure_Renaming --
599 ----------------------------------------
601 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
603 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
604 end Analyze_Generic_Procedure_Renaming
;
606 ------------------------------
607 -- Analyze_Generic_Renaming --
608 ------------------------------
610 procedure Analyze_Generic_Renaming
614 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
616 Inst
: Boolean := False; -- prevent junk warning
619 if Name
(N
) = Error
then
623 Generate_Definition
(New_P
);
625 if Current_Scope
/= Standard_Standard
then
626 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
629 if Nkind
(Name
(N
)) = N_Selected_Component
then
630 Check_Generic_Child_Unit
(Name
(N
), Inst
);
635 if not Is_Entity_Name
(Name
(N
)) then
636 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
639 Old_P
:= Entity
(Name
(N
));
643 Set_Ekind
(New_P
, K
);
645 if Etype
(Old_P
) = Any_Type
then
648 elsif Ekind
(Old_P
) /= K
then
649 Error_Msg_N
("invalid generic unit name", Name
(N
));
652 if Present
(Renamed_Object
(Old_P
)) then
653 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
655 Set_Renamed_Object
(New_P
, Old_P
);
658 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
659 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
661 Set_Etype
(New_P
, Etype
(Old_P
));
662 Set_Has_Completion
(New_P
);
664 if In_Open_Scopes
(Old_P
) then
665 Error_Msg_N
("within its scope, generic denotes its instance", N
);
668 Check_Library_Unit_Renaming
(N
, Old_P
);
670 end Analyze_Generic_Renaming
;
672 -----------------------------
673 -- Analyze_Object_Renaming --
674 -----------------------------
676 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
677 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
679 Nam
: constant Node_Id
:= Name
(N
);
683 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
684 -- Determine whether entity E is inside a generic cope
686 ----------------------
687 -- In_Generic_Scope --
688 ----------------------
690 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
695 while Present
(S
) and then S
/= Standard_Standard
loop
696 if Is_Generic_Unit
(S
) then
704 end In_Generic_Scope
;
706 -- Start of processing for Analyze_Object_Renaming
713 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
716 -- The renaming of a component that depends on a discriminant requires
717 -- an actual subtype, because in subsequent use of the object Gigi will
718 -- be unable to locate the actual bounds. This explicit step is required
719 -- when the renaming is generated in removing side effects of an
720 -- already-analyzed expression.
722 if Nkind
(Nam
) = N_Selected_Component
723 and then Analyzed
(Nam
)
726 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
728 if Present
(Dec
) then
729 Insert_Action
(N
, Dec
);
730 T
:= Defining_Identifier
(Dec
);
734 -- Complete analysis of the subtype mark in any case, for ASIS use
736 if Present
(Subtype_Mark
(N
)) then
737 Find_Type
(Subtype_Mark
(N
));
740 elsif Present
(Subtype_Mark
(N
)) then
741 Find_Type
(Subtype_Mark
(N
));
742 T
:= Entity
(Subtype_Mark
(N
));
745 if Nkind
(Nam
) = N_Type_Conversion
746 and then not Is_Tagged_Type
(T
)
749 ("renaming of conversion only allowed for tagged types", Nam
);
754 -- Check that a class-wide object is not being renamed as an object
755 -- of a specific type. The test for access types is needed to exclude
756 -- cases where the renamed object is a dynamically tagged access
757 -- result, such as occurs in certain expansions.
759 if Is_Tagged_Type
(T
) then
760 Check_Dynamically_Tagged_Expression
766 -- Ada 2005 (AI-230/AI-254): Access renaming
768 else pragma Assert
(Present
(Access_Definition
(N
)));
769 T
:= Access_Definition
771 N
=> Access_Definition
(N
));
775 -- Ada 2005 AI05-105: if the declaration has an anonymous access
776 -- type, the renamed object must also have an anonymous type, and
777 -- this is a name resolution rule. This was implicit in the last
778 -- part of the first sentence in 8.5.1.(3/2), and is made explicit
779 -- by this recent AI.
781 if not Is_Overloaded
(Nam
) then
782 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
784 ("expect anonymous access type in object renaming", N
);
791 Typ
: Entity_Id
:= Empty
;
792 Seen
: Boolean := False;
795 Get_First_Interp
(Nam
, I
, It
);
796 while Present
(It
.Typ
) loop
798 -- Renaming is ambiguous if more than one candidate
799 -- interpretation is type-conformant with the context.
801 if Ekind
(It
.Typ
) = Ekind
(T
) then
802 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
805 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
811 ("ambiguous expression in renaming", Nam
);
814 elsif Ekind
(T
) = E_Anonymous_Access_Type
816 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
822 ("ambiguous expression in renaming", Nam
);
826 if Covers
(T
, It
.Typ
) then
828 Set_Etype
(Nam
, Typ
);
829 Set_Is_Overloaded
(Nam
, False);
833 Get_Next_Interp
(I
, It
);
840 -- Ada 2005 (AI-231): "In the case where the type is defined by an
841 -- access_definition, the renamed entity shall be of an access-to-
842 -- constant type if and only if the access_definition defines an
843 -- access-to-constant type" ARM 8.5.1(4)
845 if Constant_Present
(Access_Definition
(N
))
846 and then not Is_Access_Constant
(Etype
(Nam
))
848 Error_Msg_N
("(Ada 2005): the renamed object is not "
849 & "access-to-constant (RM 8.5.1(6))", N
);
851 elsif not Constant_Present
(Access_Definition
(N
))
852 and then Is_Access_Constant
(Etype
(Nam
))
854 Error_Msg_N
("(Ada 2005): the renamed object is not "
855 & "access-to-variable (RM 8.5.1(6))", N
);
858 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
859 Check_Subtype_Conformant
860 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
862 elsif not Subtypes_Statically_Match
863 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)))
866 ("subtype of renamed object does not statically match", N
);
870 -- Special processing for renaming function return object. Some errors
871 -- and warnings are produced only for calls that come from source.
873 if Nkind
(Nam
) = N_Function_Call
then
876 -- Usage is illegal in Ada 83
879 if Comes_From_Source
(Nam
) then
881 ("(Ada 83) cannot rename function return object", Nam
);
884 -- In Ada 95, warn for odd case of renaming parameterless function
885 -- call if this is not a limited type (where this is useful).
888 if Warn_On_Object_Renames_Function
889 and then No
(Parameter_Associations
(Nam
))
890 and then not Is_Limited_Type
(Etype
(Nam
))
891 and then Comes_From_Source
(Nam
)
894 ("?renaming function result object is suspicious", Nam
);
896 ("\?function & will be called only once", Nam
,
897 Entity
(Name
(Nam
)));
898 Error_Msg_N
-- CODEFIX
899 ("\?suggest using an initialized constant object instead",
903 -- If the function call returns an unconstrained type, we must
904 -- build a constrained subtype for the new entity, in a way
905 -- similar to what is done for an object declaration with an
906 -- unconstrained nominal type.
908 if Is_Composite_Type
(Etype
(Nam
))
909 and then not Is_Constrained
(Etype
(Nam
))
910 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
911 and then Expander_Active
914 Loc
: constant Source_Ptr
:= Sloc
(N
);
915 Subt
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
917 Remove_Side_Effects
(Nam
);
919 Make_Subtype_Declaration
(Loc
,
920 Defining_Identifier
=> Subt
,
921 Subtype_Indication
=>
922 Make_Subtype_From_Expr
(Nam
, Etype
(Nam
))));
923 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
924 Set_Etype
(Nam
, Subt
);
930 -- An object renaming requires an exact match of the type. Class-wide
931 -- matching is not allowed.
933 if Is_Class_Wide_Type
(T
)
934 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
941 -- (Ada 2005: AI-326): Handle wrong use of incomplete type
943 if Nkind
(Nam
) = N_Explicit_Dereference
944 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
946 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
949 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
950 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
956 if Ada_Version
>= Ada_05
957 and then Nkind
(Nam
) = N_Attribute_Reference
958 and then Attribute_Name
(Nam
) = Name_Priority
962 elsif Ada_Version
>= Ada_05
963 and then Nkind
(Nam
) in N_Has_Entity
970 if Nkind
(Nam
) = N_Attribute_Reference
then
971 Nam_Ent
:= Entity
(Prefix
(Nam
));
973 Nam_Ent
:= Entity
(Nam
);
976 Nam_Decl
:= Parent
(Nam_Ent
);
978 if Has_Null_Exclusion
(N
)
979 and then not Has_Null_Exclusion
(Nam_Decl
)
981 -- Ada 2005 (AI-423): If the object name denotes a generic
982 -- formal object of a generic unit G, and the object renaming
983 -- declaration occurs within the body of G or within the body
984 -- of a generic unit declared within the declarative region
985 -- of G, then the declaration of the formal object of G must
986 -- have a null exclusion or a null-excluding subtype.
988 if Is_Formal_Object
(Nam_Ent
)
989 and then In_Generic_Scope
(Id
)
991 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
993 ("renamed formal does not exclude `NULL` "
994 & "(RM 8.5.1(4.6/2))", N
);
996 elsif In_Package_Body
(Scope
(Id
)) then
998 ("formal object does not have a null exclusion"
999 & "(RM 8.5.1(4.6/2))", N
);
1002 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1003 -- shall exclude null.
1005 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1007 ("renamed object does not exclude `NULL` "
1008 & "(RM 8.5.1(4.6/2))", N
);
1010 -- An instance is illegal if it contains a renaming that
1011 -- excludes null, and the actual does not. The renaming
1012 -- declaration has already indicated that the declaration
1013 -- of the renamed actual in the instance will raise
1014 -- constraint_error.
1016 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1017 and then In_Instance
1019 (Corresponding_Generic_Association
(Nam_Decl
))
1020 and then Nkind
(Expression
(Nam_Decl
))
1021 = N_Raise_Constraint_Error
1024 ("renamed actual does not exclude `NULL` "
1025 & "(RM 8.5.1(4.6/2))", N
);
1027 -- Finally, if there is a null exclusion, the subtype mark
1028 -- must not be null-excluding.
1030 elsif No
(Access_Definition
(N
))
1031 and then Can_Never_Be_Null
(T
)
1034 ("`NOT NULL` not allowed (& already excludes null)",
1039 elsif Can_Never_Be_Null
(T
)
1040 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1043 ("renamed object does not exclude `NULL` "
1044 & "(RM 8.5.1(4.6/2))", N
);
1046 elsif Has_Null_Exclusion
(N
)
1047 and then No
(Access_Definition
(N
))
1048 and then Can_Never_Be_Null
(T
)
1051 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1056 Set_Ekind
(Id
, E_Variable
);
1057 Init_Size_Align
(Id
);
1059 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1062 -- Verify that the renamed entity is an object or a function call. It
1063 -- may have been rewritten in several ways.
1065 elsif Is_Object_Reference
(Nam
) then
1066 if Comes_From_Source
(N
)
1067 and then Is_Dependent_Component_Of_Mutable_Object
(Nam
)
1070 ("illegal renaming of discriminant-dependent component", Nam
);
1073 -- A static function call may have been folded into a literal
1075 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1077 -- When expansion is disabled, attribute reference is not
1078 -- rewritten as function call. Otherwise it may be rewritten
1079 -- as a conversion, so check original node.
1081 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1082 and then Is_Function_Attribute_Name
1083 (Attribute_Name
(Original_Node
(Nam
))))
1085 -- Weird but legal, equivalent to renaming a function call.
1086 -- Illegal if the literal is the result of constant-folding an
1087 -- attribute reference that is not a function.
1089 or else (Is_Entity_Name
(Nam
)
1090 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1092 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1094 or else (Nkind
(Nam
) = N_Type_Conversion
1095 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1099 elsif Nkind
(Nam
) = N_Type_Conversion
then
1101 ("renaming of conversion only allowed for tagged types", Nam
);
1103 -- Ada 2005 (AI-327)
1105 elsif Ada_Version
>= Ada_05
1106 and then Nkind
(Nam
) = N_Attribute_Reference
1107 and then Attribute_Name
(Nam
) = Name_Priority
1111 -- Allow internally generated x'Reference expression
1113 elsif Nkind
(Nam
) = N_Reference
then
1117 Error_Msg_N
("expect object name in renaming", Nam
);
1122 if not Is_Variable
(Nam
) then
1123 Set_Ekind
(Id
, E_Constant
);
1124 Set_Never_Set_In_Source
(Id
, True);
1125 Set_Is_True_Constant
(Id
, True);
1128 Set_Renamed_Object
(Id
, Nam
);
1129 end Analyze_Object_Renaming
;
1131 ------------------------------
1132 -- Analyze_Package_Renaming --
1133 ------------------------------
1135 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1136 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1141 if Name
(N
) = Error
then
1145 -- Apply Text_IO kludge here since we may be renaming a child of Text_IO
1147 Text_IO_Kludge
(Name
(N
));
1149 if Current_Scope
/= Standard_Standard
then
1150 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1156 if Is_Entity_Name
(Name
(N
)) then
1157 Old_P
:= Entity
(Name
(N
));
1162 if Etype
(Old_P
) = Any_Type
then
1163 Error_Msg_N
("expect package name in renaming", Name
(N
));
1165 elsif Ekind
(Old_P
) /= E_Package
1166 and then not (Ekind
(Old_P
) = E_Generic_Package
1167 and then In_Open_Scopes
(Old_P
))
1169 if Ekind
(Old_P
) = E_Generic_Package
then
1171 ("generic package cannot be renamed as a package", Name
(N
));
1173 Error_Msg_Sloc
:= Sloc
(Old_P
);
1175 ("expect package name in renaming, found& declared#",
1179 -- Set basic attributes to minimize cascaded errors
1181 Set_Ekind
(New_P
, E_Package
);
1182 Set_Etype
(New_P
, Standard_Void_Type
);
1184 -- Here for OK package renaming
1187 -- Entities in the old package are accessible through the renaming
1188 -- entity. The simplest implementation is to have both packages share
1191 Set_Ekind
(New_P
, E_Package
);
1192 Set_Etype
(New_P
, Standard_Void_Type
);
1194 if Present
(Renamed_Object
(Old_P
)) then
1195 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1197 Set_Renamed_Object
(New_P
, Old_P
);
1200 Set_Has_Completion
(New_P
);
1202 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1203 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1204 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1205 Check_Library_Unit_Renaming
(N
, Old_P
);
1206 Generate_Reference
(Old_P
, Name
(N
));
1208 -- If the renaming is in the visible part of a package, then we set
1209 -- Renamed_In_Spec for the renamed package, to prevent giving
1210 -- warnings about no entities referenced. Such a warning would be
1211 -- overenthusiastic, since clients can see entities in the renamed
1212 -- package via the visible package renaming.
1215 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1217 if Ekind
(Ent
) = E_Package
1218 and then not In_Private_Part
(Ent
)
1219 and then In_Extended_Main_Source_Unit
(N
)
1220 and then Ekind
(Old_P
) = E_Package
1222 Set_Renamed_In_Spec
(Old_P
);
1226 -- If this is the renaming declaration of a package instantiation
1227 -- within itself, it is the declaration that ends the list of actuals
1228 -- for the instantiation. At this point, the subtypes that rename
1229 -- the actuals are flagged as generic, to avoid spurious ambiguities
1230 -- if the actuals for two distinct formals happen to coincide. If
1231 -- the actual is a private type, the subtype has a private completion
1232 -- that is flagged in the same fashion.
1234 -- Resolution is identical to what is was in the original generic.
1235 -- On exit from the generic instance, these are turned into regular
1236 -- subtypes again, so they are compatible with types in their class.
1238 if not Is_Generic_Instance
(Old_P
) then
1241 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1244 if Nkind
(Spec
) = N_Package_Specification
1245 and then Present
(Generic_Parent
(Spec
))
1246 and then Old_P
= Current_Scope
1247 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1253 E
:= First_Entity
(Old_P
);
1258 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1260 Set_Is_Generic_Actual_Type
(E
);
1262 if Is_Private_Type
(E
)
1263 and then Present
(Full_View
(E
))
1265 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1274 end Analyze_Package_Renaming
;
1276 -------------------------------
1277 -- Analyze_Renamed_Character --
1278 -------------------------------
1280 procedure Analyze_Renamed_Character
1285 C
: constant Node_Id
:= Name
(N
);
1288 if Ekind
(New_S
) = E_Function
then
1289 Resolve
(C
, Etype
(New_S
));
1292 Check_Frozen_Renaming
(N
, New_S
);
1296 Error_Msg_N
("character literal can only be renamed as function", N
);
1298 end Analyze_Renamed_Character
;
1300 ---------------------------------
1301 -- Analyze_Renamed_Dereference --
1302 ---------------------------------
1304 procedure Analyze_Renamed_Dereference
1309 Nam
: constant Node_Id
:= Name
(N
);
1310 P
: constant Node_Id
:= Prefix
(Nam
);
1316 if not Is_Overloaded
(P
) then
1317 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1318 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1320 Error_Msg_N
("designated type does not match specification", P
);
1329 Get_First_Interp
(Nam
, Ind
, It
);
1331 while Present
(It
.Nam
) loop
1333 if Ekind
(It
.Nam
) = E_Subprogram_Type
1334 and then Type_Conformant
(It
.Nam
, New_S
)
1336 if Typ
/= Any_Id
then
1337 Error_Msg_N
("ambiguous renaming", P
);
1344 Get_Next_Interp
(Ind
, It
);
1347 if Typ
= Any_Type
then
1348 Error_Msg_N
("designated type does not match specification", P
);
1353 Check_Frozen_Renaming
(N
, New_S
);
1357 end Analyze_Renamed_Dereference
;
1359 ---------------------------
1360 -- Analyze_Renamed_Entry --
1361 ---------------------------
1363 procedure Analyze_Renamed_Entry
1368 Nam
: constant Node_Id
:= Name
(N
);
1369 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1373 if Entity
(Sel
) = Any_Id
then
1375 -- Selector is undefined on prefix. Error emitted already
1377 Set_Has_Completion
(New_S
);
1381 -- Otherwise find renamed entity and build body of New_S as a call to it
1383 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1385 if Old_S
= Any_Id
then
1386 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1389 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1390 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1391 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1394 -- Only mode conformance required for a renaming_as_declaration
1396 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1399 Inherit_Renamed_Profile
(New_S
, Old_S
);
1401 -- The prefix can be an arbitrary expression that yields a task type,
1402 -- so it must be resolved.
1404 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1407 Set_Convention
(New_S
, Convention
(Old_S
));
1408 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1411 Check_Frozen_Renaming
(N
, New_S
);
1413 end Analyze_Renamed_Entry
;
1415 -----------------------------------
1416 -- Analyze_Renamed_Family_Member --
1417 -----------------------------------
1419 procedure Analyze_Renamed_Family_Member
1424 Nam
: constant Node_Id
:= Name
(N
);
1425 P
: constant Node_Id
:= Prefix
(Nam
);
1429 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1430 or else (Nkind
(P
) = N_Selected_Component
1432 Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1434 if Is_Entity_Name
(P
) then
1435 Old_S
:= Entity
(P
);
1437 Old_S
:= Entity
(Selector_Name
(P
));
1440 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1441 Error_Msg_N
("entry family does not match specification", N
);
1444 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1445 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1446 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1450 Error_Msg_N
("no entry family matches specification", N
);
1453 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1456 Check_Frozen_Renaming
(N
, New_S
);
1458 end Analyze_Renamed_Family_Member
;
1460 -----------------------------------------
1461 -- Analyze_Renamed_Primitive_Operation --
1462 -----------------------------------------
1464 procedure Analyze_Renamed_Primitive_Operation
1473 Ctyp
: Conformance_Type
) return Boolean;
1474 -- Verify that the signatures of the renamed entity and the new entity
1475 -- match. The first formal of the renamed entity is skipped because it
1476 -- is the target object in any subsequent call.
1480 Ctyp
: Conformance_Type
) return Boolean
1486 if Ekind
(Subp
) /= Ekind
(New_S
) then
1490 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1491 New_F
:= First_Formal
(New_S
);
1492 while Present
(Old_F
) and then Present
(New_F
) loop
1493 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1497 if Ctyp
>= Mode_Conformant
1498 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1503 Next_Formal
(New_F
);
1504 Next_Formal
(Old_F
);
1511 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1512 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1514 if not Conforms
(Old_S
, Type_Conformant
) then
1519 -- Find the operation that matches the given signature
1527 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1529 while Present
(It
.Nam
) loop
1530 if Conforms
(It
.Nam
, Type_Conformant
) then
1534 Get_Next_Interp
(Ind
, It
);
1539 if Old_S
= Any_Id
then
1540 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1544 if not Conforms
(Old_S
, Subtype_Conformant
) then
1545 Error_Msg_N
("subtype conformance error in renaming", N
);
1548 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1549 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1552 -- Only mode conformance required for a renaming_as_declaration
1554 if not Conforms
(Old_S
, Mode_Conformant
) then
1555 Error_Msg_N
("mode conformance error in renaming", N
);
1559 -- Inherit_Renamed_Profile (New_S, Old_S);
1561 -- The prefix can be an arbitrary expression that yields an
1562 -- object, so it must be resolved.
1564 Resolve
(Prefix
(Name
(N
)));
1566 end Analyze_Renamed_Primitive_Operation
;
1568 ---------------------------------
1569 -- Analyze_Subprogram_Renaming --
1570 ---------------------------------
1572 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1573 Formal_Spec
: constant Node_Id
:= Corresponding_Formal_Spec
(N
);
1574 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1575 Inst_Node
: Node_Id
:= Empty
;
1576 Nam
: constant Node_Id
:= Name
(N
);
1578 Old_S
: Entity_Id
:= Empty
;
1579 Rename_Spec
: Entity_Id
;
1580 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1581 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1582 Spec
: constant Node_Id
:= Specification
(N
);
1584 procedure Check_Null_Exclusion
1587 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1588 -- following AI rules:
1590 -- If Ren is a renaming of a formal subprogram and one of its
1591 -- parameters has a null exclusion, then the corresponding formal
1592 -- in Sub must also have one. Otherwise the subtype of the Sub's
1593 -- formal parameter must exclude null.
1595 -- If Ren is a renaming of a formal function and its return
1596 -- profile has a null exclusion, then Sub's return profile must
1597 -- have one. Otherwise the subtype of Sub's return profile must
1600 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1601 -- Find renamed entity when the declaration is a renaming_as_body and
1602 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1603 -- rule that a renaming_as_body is illegal if the declaration occurs
1604 -- before the subprogram it completes is frozen, and renaming indirectly
1605 -- renames the subprogram itself.(Defect Report 8652/0027).
1607 --------------------------
1608 -- Check_Null_Exclusion --
1609 --------------------------
1611 procedure Check_Null_Exclusion
1615 Ren_Formal
: Entity_Id
;
1616 Sub_Formal
: Entity_Id
;
1621 Ren_Formal
:= First_Formal
(Ren
);
1622 Sub_Formal
:= First_Formal
(Sub
);
1623 while Present
(Ren_Formal
)
1624 and then Present
(Sub_Formal
)
1626 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
1628 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
1629 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
1632 ("`NOT NULL` required for parameter &",
1633 Parent
(Sub_Formal
), Sub_Formal
);
1636 Next_Formal
(Ren_Formal
);
1637 Next_Formal
(Sub_Formal
);
1640 -- Return profile check
1642 if Nkind
(Parent
(Ren
)) = N_Function_Specification
1643 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
1644 and then Has_Null_Exclusion
(Parent
(Ren
))
1646 not (Has_Null_Exclusion
(Parent
(Sub
))
1647 or else Can_Never_Be_Null
(Etype
(Sub
)))
1650 ("return must specify `NOT NULL`",
1651 Result_Definition
(Parent
(Sub
)));
1653 end Check_Null_Exclusion
;
1655 -------------------------
1656 -- Original_Subprogram --
1657 -------------------------
1659 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
1660 Orig_Decl
: Node_Id
;
1661 Orig_Subp
: Entity_Id
;
1664 -- First case: renamed entity is itself a renaming
1666 if Present
(Alias
(Subp
)) then
1667 return Alias
(Subp
);
1670 Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
1672 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
1674 -- Check if renamed entity is a renaming_as_body
1677 Unit_Declaration_Node
1678 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
1680 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
1681 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
1683 if Orig_Subp
= Rename_Spec
then
1685 -- Circularity detected
1690 return (Original_Subprogram
(Orig_Subp
));
1698 end Original_Subprogram
;
1700 -- Start of processing for Analyze_Subprogram_Renaming
1703 -- We must test for the attribute renaming case before the Analyze
1704 -- call because otherwise Sem_Attr will complain that the attribute
1705 -- is missing an argument when it is analyzed.
1707 if Nkind
(Nam
) = N_Attribute_Reference
then
1709 -- In the case of an abstract formal subprogram association, rewrite
1710 -- an actual given by a stream attribute as the name of the
1711 -- corresponding stream primitive of the type.
1713 -- In a generic context the stream operations are not generated, and
1714 -- this must be treated as a normal attribute reference, to be
1715 -- expanded in subsequent instantiations.
1717 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
)
1718 and then Expander_Active
1721 Stream_Prim
: Entity_Id
;
1722 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
1725 -- The class-wide forms of the stream attributes are not
1726 -- primitive dispatching operations (even though they
1727 -- internally dispatch to a stream attribute).
1729 if Is_Class_Wide_Type
(Prefix_Type
) then
1731 ("attribute must be a primitive dispatching operation",
1736 -- Retrieve the primitive subprogram associated with the
1737 -- attribute. This can only be a stream attribute, since those
1738 -- are the only ones that are dispatching (and the actual for
1739 -- an abstract formal subprogram must be dispatching
1743 case Attribute_Name
(Nam
) is
1746 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
1749 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
1752 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
1755 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
1758 ("attribute must be a primitive"
1759 & " dispatching operation", Nam
);
1765 -- If no operation was found, and the type is limited,
1766 -- the user should have defined one.
1768 when Program_Error
=>
1769 if Is_Limited_Type
(Prefix_Type
) then
1771 ("stream operation not defined for type&",
1775 -- Otherwise, compiler should have generated default
1782 -- Rewrite the attribute into the name of its corresponding
1783 -- primitive dispatching subprogram. We can then proceed with
1784 -- the usual processing for subprogram renamings.
1787 Prim_Name
: constant Node_Id
:=
1788 Make_Identifier
(Sloc
(Nam
),
1789 Chars
=> Chars
(Stream_Prim
));
1791 Set_Entity
(Prim_Name
, Stream_Prim
);
1792 Rewrite
(Nam
, Prim_Name
);
1797 -- Normal processing for a renaming of an attribute
1800 Attribute_Renaming
(N
);
1805 -- Check whether this declaration corresponds to the instantiation
1806 -- of a formal subprogram.
1808 -- If this is an instantiation, the corresponding actual is frozen and
1809 -- error messages can be made more precise. If this is a default
1810 -- subprogram, the entity is already established in the generic, and is
1811 -- not retrieved by visibility. If it is a default with a box, the
1812 -- candidate interpretations, if any, have been collected when building
1813 -- the renaming declaration. If overloaded, the proper interpretation is
1814 -- determined in Find_Renamed_Entity. If the entity is an operator,
1815 -- Find_Renamed_Entity applies additional visibility checks.
1818 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
1820 if Is_Entity_Name
(Nam
)
1821 and then Present
(Entity
(Nam
))
1822 and then not Comes_From_Source
(Nam
)
1823 and then not Is_Overloaded
(Nam
)
1825 Old_S
:= Entity
(Nam
);
1826 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1830 if Ekind
(Entity
(Nam
)) = E_Operator
then
1834 if Box_Present
(Inst_Node
) then
1835 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
1837 -- If there is an immediately visible homonym of the operator
1838 -- and the declaration has a default, this is worth a warning
1839 -- because the user probably did not intend to get the pre-
1840 -- defined operator, visible in the generic declaration. To
1841 -- find if there is an intended candidate, analyze the renaming
1842 -- again in the current context.
1844 elsif Scope
(Old_S
) = Standard_Standard
1845 and then Present
(Default_Name
(Inst_Node
))
1848 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
1852 Set_Entity
(Name
(Decl
), Empty
);
1853 Analyze
(Name
(Decl
));
1855 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
1858 and then In_Open_Scopes
(Scope
(Hidden
))
1859 and then Is_Immediately_Visible
(Hidden
)
1860 and then Comes_From_Source
(Hidden
)
1861 and then Hidden
/= Old_S
1863 Error_Msg_Sloc
:= Sloc
(Hidden
);
1864 Error_Msg_N
("?default subprogram is resolved " &
1865 "in the generic declaration " &
1866 "(RM 12.6(17))", N
);
1867 Error_Msg_NE
("\?and will not use & #", N
, Hidden
);
1875 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1879 -- Renamed entity must be analyzed first, to avoid being hidden by
1880 -- new name (which might be the same in a generic instance).
1884 -- The renaming defines a new overloaded entity, which is analyzed
1885 -- like a subprogram declaration.
1887 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1890 if Current_Scope
/= Standard_Standard
then
1891 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
1894 Rename_Spec
:= Find_Corresponding_Spec
(N
);
1896 -- Case of Renaming_As_Body
1898 if Present
(Rename_Spec
) then
1900 -- Renaming declaration is the completion of the declaration of
1901 -- Rename_Spec. We build an actual body for it at the freezing point.
1903 Set_Corresponding_Spec
(N
, Rename_Spec
);
1905 -- Deal with special case of stream functions of abstract types
1908 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
1909 N_Abstract_Subprogram_Declaration
1911 -- Input stream functions are abstract if the object type is
1912 -- abstract. Similarly, all default stream functions for an
1913 -- interface type are abstract. However, these subprograms may
1914 -- receive explicit declarations in representation clauses, making
1915 -- the attribute subprograms usable as defaults in subsequent
1917 -- In this case we rewrite the declaration to make the subprogram
1918 -- non-abstract. We remove the previous declaration, and insert
1919 -- the new one at the point of the renaming, to prevent premature
1920 -- access to unfrozen types. The new declaration reuses the
1921 -- specification of the previous one, and must not be analyzed.
1924 (Is_Primitive
(Entity
(Nam
))
1926 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
1928 Old_Decl
: constant Node_Id
:=
1929 Unit_Declaration_Node
(Rename_Spec
);
1930 New_Decl
: constant Node_Id
:=
1931 Make_Subprogram_Declaration
(Sloc
(N
),
1933 Relocate_Node
(Specification
(Old_Decl
)));
1936 Insert_After
(N
, New_Decl
);
1937 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
1938 Set_Analyzed
(New_Decl
);
1942 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
1944 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
1945 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
1948 Set_Convention
(New_S
, Convention
(Rename_Spec
));
1949 Check_Fully_Conformant
(New_S
, Rename_Spec
);
1950 Set_Public_Status
(New_S
);
1952 -- The specification does not introduce new formals, but only
1953 -- repeats the formals of the original subprogram declaration.
1954 -- For cross-reference purposes, and for refactoring tools, we
1955 -- treat the formals of the renaming declaration as body formals.
1957 Reference_Body_Formals
(Rename_Spec
, New_S
);
1959 -- Indicate that the entity in the declaration functions like the
1960 -- corresponding body, and is not a new entity. The body will be
1961 -- constructed later at the freeze point, so indicate that the
1962 -- completion has not been seen yet.
1964 Set_Ekind
(New_S
, E_Subprogram_Body
);
1965 New_S
:= Rename_Spec
;
1966 Set_Has_Completion
(Rename_Spec
, False);
1968 -- Ada 2005: check overriding indicator
1970 if Is_Overriding_Operation
(Rename_Spec
) then
1971 if Must_Not_Override
(Specification
(N
)) then
1973 ("subprogram& overrides inherited operation",
1976 Style_Check
and then not Must_Override
(Specification
(N
))
1978 Style
.Missing_Overriding
(N
, Rename_Spec
);
1981 elsif Must_Override
(Specification
(N
)) then
1982 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
1985 -- Normal subprogram renaming (not renaming as body)
1988 Generate_Definition
(New_S
);
1989 New_Overloaded_Entity
(New_S
);
1991 if Is_Entity_Name
(Nam
)
1992 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
1996 Check_Delayed_Subprogram
(New_S
);
2000 -- There is no need for elaboration checks on the new entity, which may
2001 -- be called before the next freezing point where the body will appear.
2002 -- Elaboration checks refer to the real entity, not the one created by
2003 -- the renaming declaration.
2005 Set_Kill_Elaboration_Checks
(New_S
, True);
2007 if Etype
(Nam
) = Any_Type
then
2008 Set_Has_Completion
(New_S
);
2011 elsif Nkind
(Nam
) = N_Selected_Component
then
2013 -- A prefix of the form A.B can designate an entry of task A, a
2014 -- protected operation of protected object A, or finally a primitive
2015 -- operation of object A. In the later case, A is an object of some
2016 -- tagged type, or an access type that denotes one such. To further
2017 -- distinguish these cases, note that the scope of a task entry or
2018 -- protected operation is type of the prefix.
2020 -- The prefix could be an overloaded function call that returns both
2021 -- kinds of operations. This overloading pathology is left to the
2022 -- dedicated reader ???
2025 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2034 Is_Tagged_Type
(Designated_Type
(T
))))
2035 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2037 Analyze_Renamed_Primitive_Operation
2038 (N
, New_S
, Present
(Rename_Spec
));
2042 -- Renamed entity is an entry or protected operation. For those
2043 -- cases an explicit body is built (at the point of freezing of
2044 -- this entity) that contains a call to the renamed entity.
2046 -- This is not allowed for renaming as body if the renamed
2047 -- spec is already frozen (see RM 8.5.4(5) for details).
2049 if Present
(Rename_Spec
)
2050 and then Is_Frozen
(Rename_Spec
)
2053 ("renaming-as-body cannot rename entry as subprogram", N
);
2055 ("\since & is already frozen (RM 8.5.4(5))",
2058 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
2065 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
2067 -- Renamed entity is designated by access_to_subprogram expression.
2068 -- Must build body to encapsulate call, as in the entry case.
2070 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
2073 elsif Nkind
(Nam
) = N_Indexed_Component
then
2074 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
2077 elsif Nkind
(Nam
) = N_Character_Literal
then
2078 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
2081 elsif (not Is_Entity_Name
(Nam
)
2082 and then Nkind
(Nam
) /= N_Operator_Symbol
)
2083 or else not Is_Overloadable
(Entity
(Nam
))
2085 Error_Msg_N
("expect valid subprogram name in renaming", N
);
2089 -- Find the renamed entity that matches the given specification. Disable
2090 -- Ada_83 because there is no requirement of full conformance between
2091 -- renamed entity and new entity, even though the same circuit is used.
2093 -- This is a bit of a kludge, which introduces a really irregular use of
2094 -- Ada_Version[_Explicit]. Would be nice to find cleaner way to do this
2097 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
2098 Ada_Version_Explicit
:= Ada_Version
;
2101 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2103 -- When the renamed subprogram is overloaded and used as an actual
2104 -- of a generic, its entity is set to the first available homonym.
2105 -- We must first disambiguate the name, then set the proper entity.
2108 and then Is_Overloaded
(Nam
)
2110 Set_Entity
(Nam
, Old_S
);
2114 -- Most common case: subprogram renames subprogram. No body is generated
2115 -- in this case, so we must indicate the declaration is complete as is.
2116 -- and inherit various attributes of the renamed subprogram.
2118 if No
(Rename_Spec
) then
2119 Set_Has_Completion
(New_S
);
2120 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
2121 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
2122 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
2124 -- Ada 2005 (AI-423): Check the consistency of null exclusions
2125 -- between a subprogram and its correct renaming.
2127 -- Note: the Any_Id check is a guard that prevents compiler crashes
2128 -- when performing a null exclusion check between a renaming and a
2129 -- renamed subprogram that has been found to be illegal.
2131 if Ada_Version
>= Ada_05
2132 and then Entity
(Nam
) /= Any_Id
2134 Check_Null_Exclusion
2136 Sub
=> Entity
(Nam
));
2139 -- Enforce the Ada 2005 rule that the renamed entity cannot require
2140 -- overriding. The flag Requires_Overriding is set very selectively
2141 -- and misses some other illegal cases. The additional conditions
2142 -- checked below are sufficient but not necessary ???
2144 -- The rule does not apply to the renaming generated for an actual
2145 -- subprogram in an instance.
2150 -- Guard against previous errors, and omit renamings of predefined
2153 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
2156 elsif Requires_Overriding
(Old_S
)
2158 (Is_Abstract_Subprogram
(Old_S
)
2159 and then Present
(Find_Dispatching_Type
(Old_S
))
2161 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
2164 ("renamed entity cannot be "
2165 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
2169 if Old_S
/= Any_Id
then
2171 and then From_Default
(N
)
2173 -- This is an implicit reference to the default actual
2175 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
2177 Generate_Reference
(Old_S
, Nam
);
2180 -- For a renaming-as-body, require subtype conformance, but if the
2181 -- declaration being completed has not been frozen, then inherit the
2182 -- convention of the renamed subprogram prior to checking conformance
2183 -- (unless the renaming has an explicit convention established; the
2184 -- rule stated in the RM doesn't seem to address this ???).
2186 if Present
(Rename_Spec
) then
2187 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
2188 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
2190 if not Is_Frozen
(Rename_Spec
) then
2191 if not Has_Convention_Pragma
(Rename_Spec
) then
2192 Set_Convention
(New_S
, Convention
(Old_S
));
2195 if Ekind
(Old_S
) /= E_Operator
then
2196 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
2199 if Original_Subprogram
(Old_S
) = Rename_Spec
then
2200 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
2203 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
2206 Check_Frozen_Renaming
(N
, Rename_Spec
);
2208 -- Check explicitly that renamed entity is not intrinsic, because
2209 -- in a generic the renamed body is not built. In this case,
2210 -- the renaming_as_body is a completion.
2212 if Inside_A_Generic
then
2213 if Is_Frozen
(Rename_Spec
)
2214 and then Is_Intrinsic_Subprogram
(Old_S
)
2217 ("subprogram in renaming_as_body cannot be intrinsic",
2221 Set_Has_Completion
(Rename_Spec
);
2224 elsif Ekind
(Old_S
) /= E_Operator
then
2225 Check_Mode_Conformant
(New_S
, Old_S
);
2228 and then Error_Posted
(New_S
)
2230 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
2234 if No
(Rename_Spec
) then
2236 -- The parameter profile of the new entity is that of the renamed
2237 -- entity: the subtypes given in the specification are irrelevant.
2239 Inherit_Renamed_Profile
(New_S
, Old_S
);
2241 -- A call to the subprogram is transformed into a call to the
2242 -- renamed entity. This is transitive if the renamed entity is
2243 -- itself a renaming.
2245 if Present
(Alias
(Old_S
)) then
2246 Set_Alias
(New_S
, Alias
(Old_S
));
2248 Set_Alias
(New_S
, Old_S
);
2251 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
2252 -- renaming as body, since the entity in this case is not an
2253 -- intrinsic (it calls an intrinsic, but we have a real body for
2254 -- this call, and it is in this body that the required intrinsic
2255 -- processing will take place).
2257 -- Also, if this is a renaming of inequality, the renamed operator
2258 -- is intrinsic, but what matters is the corresponding equality
2259 -- operator, which may be user-defined.
2261 Set_Is_Intrinsic_Subprogram
2263 Is_Intrinsic_Subprogram
(Old_S
)
2265 (Chars
(Old_S
) /= Name_Op_Ne
2266 or else Ekind
(Old_S
) = E_Operator
2268 Is_Intrinsic_Subprogram
2269 (Corresponding_Equality
(Old_S
))));
2271 if Ekind
(Alias
(New_S
)) = E_Operator
then
2272 Set_Has_Delayed_Freeze
(New_S
, False);
2275 -- If the renaming corresponds to an association for an abstract
2276 -- formal subprogram, then various attributes must be set to
2277 -- indicate that the renaming is an abstract dispatching operation
2278 -- with a controlling type.
2280 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
2282 -- Mark the renaming as abstract here, so Find_Dispatching_Type
2283 -- see it as corresponding to a generic association for a
2284 -- formal abstract subprogram
2286 Set_Is_Abstract_Subprogram
(New_S
);
2289 New_S_Ctrl_Type
: constant Entity_Id
:=
2290 Find_Dispatching_Type
(New_S
);
2291 Old_S_Ctrl_Type
: constant Entity_Id
:=
2292 Find_Dispatching_Type
(Old_S
);
2295 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
2297 ("actual must be dispatching subprogram for type&",
2298 Nam
, New_S_Ctrl_Type
);
2301 Set_Is_Dispatching_Operation
(New_S
);
2302 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
2304 -- If the actual in the formal subprogram is itself a
2305 -- formal abstract subprogram association, there's no
2306 -- dispatch table component or position to inherit.
2308 if Present
(DTC_Entity
(Old_S
)) then
2309 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
2310 Set_DT_Position
(New_S
, DT_Position
(Old_S
));
2318 and then (Old_S
= New_S
2319 or else (Nkind
(Nam
) /= N_Expanded_Name
2320 and then Chars
(Old_S
) = Chars
(New_S
)))
2322 Error_Msg_N
("subprogram cannot rename itself", N
);
2325 Set_Convention
(New_S
, Convention
(Old_S
));
2327 if Is_Abstract_Subprogram
(Old_S
) then
2328 if Present
(Rename_Spec
) then
2330 ("a renaming-as-body cannot rename an abstract subprogram",
2332 Set_Has_Completion
(Rename_Spec
);
2334 Set_Is_Abstract_Subprogram
(New_S
);
2338 Check_Library_Unit_Renaming
(N
, Old_S
);
2340 -- Pathological case: procedure renames entry in the scope of its
2341 -- task. Entry is given by simple name, but body must be built for
2342 -- procedure. Of course if called it will deadlock.
2344 if Ekind
(Old_S
) = E_Entry
then
2345 Set_Has_Completion
(New_S
, False);
2346 Set_Alias
(New_S
, Empty
);
2350 Freeze_Before
(N
, Old_S
);
2351 Set_Has_Delayed_Freeze
(New_S
, False);
2352 Freeze_Before
(N
, New_S
);
2354 -- An abstract subprogram is only allowed as an actual in the case
2355 -- where the formal subprogram is also abstract.
2357 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
2358 and then Is_Abstract_Subprogram
(Old_S
)
2359 and then not Is_Abstract_Subprogram
(Formal_Spec
)
2362 ("abstract subprogram not allowed as generic actual", Nam
);
2367 -- A common error is to assume that implicit operators for types are
2368 -- defined in Standard, or in the scope of a subtype. In those cases
2369 -- where the renamed entity is given with an expanded name, it is
2370 -- worth mentioning that operators for the type are not declared in
2371 -- the scope given by the prefix.
2373 if Nkind
(Nam
) = N_Expanded_Name
2374 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
2375 and then Scope
(Entity
(Nam
)) = Standard_Standard
2378 T
: constant Entity_Id
:=
2379 Base_Type
(Etype
(First_Formal
(New_S
)));
2381 Error_Msg_Node_2
:= Prefix
(Nam
);
2383 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
2388 ("no visible subprogram matches the specification for&",
2392 if Present
(Candidate_Renaming
) then
2399 F1
:= First_Formal
(Candidate_Renaming
);
2400 F2
:= First_Formal
(New_S
);
2401 T1
:= First_Subtype
(Etype
(F1
));
2403 while Present
(F1
) and then Present
(F2
) loop
2408 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
2409 if Present
(Next_Formal
(F1
)) then
2411 ("\missing specification for &" &
2412 " and other formals with defaults", Spec
, F1
);
2415 ("\missing specification for &", Spec
, F1
);
2419 if Nkind
(Nam
) = N_Operator_Symbol
2420 and then From_Default
(N
)
2422 Error_Msg_Node_2
:= T1
;
2424 ("default & on & is not directly visible",
2431 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
2432 -- controlling access parameters are known non-null for the renamed
2433 -- subprogram. Test also applies to a subprogram instantiation that
2434 -- is dispatching. Test is skipped if some previous error was detected
2435 -- that set Old_S to Any_Id.
2437 if Ada_Version
>= Ada_05
2438 and then Old_S
/= Any_Id
2439 and then not Is_Dispatching_Operation
(Old_S
)
2440 and then Is_Dispatching_Operation
(New_S
)
2447 Old_F
:= First_Formal
(Old_S
);
2448 New_F
:= First_Formal
(New_S
);
2449 while Present
(Old_F
) loop
2450 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
2451 and then Is_Controlling_Formal
(New_F
)
2452 and then not Can_Never_Be_Null
(Old_F
)
2454 Error_Msg_N
("access parameter is controlling,", New_F
);
2456 ("\corresponding parameter of& "
2457 & "must be explicitly null excluding", New_F
, Old_S
);
2460 Next_Formal
(Old_F
);
2461 Next_Formal
(New_F
);
2466 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
2467 -- is to warn if an operator is being renamed as a different operator.
2469 if Comes_From_Source
(N
)
2470 and then Present
(Old_S
)
2471 and then Nkind
(Old_S
) = N_Defining_Operator_Symbol
2472 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
2473 and then Chars
(Old_S
) /= Chars
(New_S
)
2476 ("?& is being renamed as a different operator",
2480 -- Check for renaming of obsolescent subprogram
2482 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
2484 -- Another warning or some utility: if the new subprogram as the same
2485 -- name as the old one, the old one is not hidden by an outer homograph,
2486 -- the new one is not a public symbol, and the old one is otherwise
2487 -- directly visible, the renaming is superfluous.
2489 if Chars
(Old_S
) = Chars
(New_S
)
2490 and then Comes_From_Source
(N
)
2491 and then Scope
(Old_S
) /= Standard_Standard
2492 and then Warn_On_Redundant_Constructs
2494 (Is_Immediately_Visible
(Old_S
)
2495 or else Is_Potentially_Use_Visible
(Old_S
))
2496 and then Is_Overloadable
(Current_Scope
)
2497 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
2500 ("?redundant renaming, entity is directly visible", Name
(N
));
2503 Ada_Version
:= Save_AV
;
2504 Ada_Version_Explicit
:= Save_AV_Exp
;
2505 end Analyze_Subprogram_Renaming
;
2507 -------------------------
2508 -- Analyze_Use_Package --
2509 -------------------------
2511 -- Resolve the package names in the use clause, and make all the visible
2512 -- entities defined in the package potentially use-visible. If the package
2513 -- is already in use from a previous use clause, its visible entities are
2514 -- already use-visible. In that case, mark the occurrence as a redundant
2515 -- use. If the package is an open scope, i.e. if the use clause occurs
2516 -- within the package itself, ignore it.
2518 procedure Analyze_Use_Package
(N
: Node_Id
) is
2519 Pack_Name
: Node_Id
;
2522 -- Start of processing for Analyze_Use_Package
2525 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
2527 -- Use clause is not allowed in a spec of a predefined package
2528 -- declaration except that packages whose file name starts a-n are OK
2529 -- (these are children of Ada.Numerics, and such packages are never
2530 -- loaded by Rtsfind).
2532 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
2533 and then Name_Buffer
(1 .. 3) /= "a-n"
2535 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
2537 Error_Msg_N
("use clause not allowed in predefined spec", N
);
2540 -- Chain clause to list of use clauses in current scope
2542 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
2543 Chain_Use_Clause
(N
);
2546 -- Loop through package names to identify referenced packages
2548 Pack_Name
:= First
(Names
(N
));
2549 while Present
(Pack_Name
) loop
2550 Analyze
(Pack_Name
);
2552 if Nkind
(Parent
(N
)) = N_Compilation_Unit
2553 and then Nkind
(Pack_Name
) = N_Expanded_Name
2559 Pref
:= Prefix
(Pack_Name
);
2560 while Nkind
(Pref
) = N_Expanded_Name
loop
2561 Pref
:= Prefix
(Pref
);
2564 if Entity
(Pref
) = Standard_Standard
then
2566 ("predefined package Standard cannot appear"
2567 & " in a context clause", Pref
);
2575 -- Loop through package names to mark all entities as potentially
2578 Pack_Name
:= First
(Names
(N
));
2579 while Present
(Pack_Name
) loop
2580 if Is_Entity_Name
(Pack_Name
) then
2581 Pack
:= Entity
(Pack_Name
);
2583 if Ekind
(Pack
) /= E_Package
2584 and then Etype
(Pack
) /= Any_Type
2586 if Ekind
(Pack
) = E_Generic_Package
then
2587 Error_Msg_N
-- CODEFIX
2588 ("a generic package is not allowed in a use clause",
2591 Error_Msg_N
("& is not a usable package", Pack_Name
);
2595 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
2596 Check_In_Previous_With_Clause
(N
, Pack_Name
);
2599 if Applicable_Use
(Pack_Name
) then
2600 Use_One_Package
(Pack
, N
);
2604 -- Report error because name denotes something other than a package
2607 Error_Msg_N
("& is not a package", Pack_Name
);
2612 end Analyze_Use_Package
;
2614 ----------------------
2615 -- Analyze_Use_Type --
2616 ----------------------
2618 procedure Analyze_Use_Type
(N
: Node_Id
) is
2623 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
2625 -- Chain clause to list of use clauses in current scope
2627 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
2628 Chain_Use_Clause
(N
);
2631 Id
:= First
(Subtype_Marks
(N
));
2632 while Present
(Id
) loop
2636 if E
/= Any_Type
then
2639 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
2640 if Nkind
(Id
) = N_Identifier
then
2641 Error_Msg_N
("type is not directly visible", Id
);
2643 elsif Is_Child_Unit
(Scope
(E
))
2644 and then Scope
(E
) /= System_Aux_Id
2646 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
2651 -- If the use_type_clause appears in a compilation unit context,
2652 -- check whether it comes from a unit that may appear in a
2653 -- limited_with_clause, for a better error message.
2655 if Nkind
(Parent
(N
)) = N_Compilation_Unit
2656 and then Nkind
(Id
) /= N_Identifier
2662 function Mentioned
(Nam
: Node_Id
) return Boolean;
2663 -- Check whether the prefix of expanded name for the type
2664 -- appears in the prefix of some limited_with_clause.
2670 function Mentioned
(Nam
: Node_Id
) return Boolean is
2672 return Nkind
(Name
(Item
)) = N_Selected_Component
2674 Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
2678 Pref
:= Prefix
(Id
);
2679 Item
:= First
(Context_Items
(Parent
(N
)));
2681 while Present
(Item
) and then Item
/= N
loop
2682 if Nkind
(Item
) = N_With_Clause
2683 and then Limited_Present
(Item
)
2684 and then Mentioned
(Pref
)
2687 (Get_Msg_Id
, "premature usage of incomplete type");
2698 end Analyze_Use_Type
;
2700 --------------------
2701 -- Applicable_Use --
2702 --------------------
2704 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
2705 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
2708 if In_Open_Scopes
(Pack
) then
2709 if Warn_On_Redundant_Constructs
2710 and then Pack
= Current_Scope
2712 Error_Msg_NE
-- CODEFIX
2713 ("& is already use-visible within itself?", Pack_Name
, Pack
);
2718 elsif In_Use
(Pack
) then
2719 Note_Redundant_Use
(Pack_Name
);
2722 elsif Present
(Renamed_Object
(Pack
))
2723 and then In_Use
(Renamed_Object
(Pack
))
2725 Note_Redundant_Use
(Pack_Name
);
2733 ------------------------
2734 -- Attribute_Renaming --
2735 ------------------------
2737 procedure Attribute_Renaming
(N
: Node_Id
) is
2738 Loc
: constant Source_Ptr
:= Sloc
(N
);
2739 Nam
: constant Node_Id
:= Name
(N
);
2740 Spec
: constant Node_Id
:= Specification
(N
);
2741 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
2742 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
2744 Form_Num
: Nat
:= 0;
2745 Expr_List
: List_Id
:= No_List
;
2747 Attr_Node
: Node_Id
;
2748 Body_Node
: Node_Id
;
2749 Param_Spec
: Node_Id
;
2752 Generate_Definition
(New_S
);
2754 -- This procedure is called in the context of subprogram renaming, and
2755 -- thus the attribute must be one that is a subprogram. All of those
2756 -- have at least one formal parameter, with the singular exception of
2757 -- AST_Entry (which is a real oddity, it is odd that this can be renamed
2760 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
2761 if Aname
/= Name_AST_Entry
then
2763 ("subprogram renaming an attribute must have formals", N
);
2768 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
2769 while Present
(Param_Spec
) loop
2770 Form_Num
:= Form_Num
+ 1;
2772 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
2773 Find_Type
(Parameter_Type
(Param_Spec
));
2775 -- The profile of the new entity denotes the base type (s) of
2776 -- the types given in the specification. For access parameters
2777 -- there are no subtypes involved.
2779 Rewrite
(Parameter_Type
(Param_Spec
),
2781 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
2784 if No
(Expr_List
) then
2785 Expr_List
:= New_List
;
2788 Append_To
(Expr_List
,
2789 Make_Identifier
(Loc
,
2790 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
2792 -- The expressions in the attribute reference are not freeze
2793 -- points. Neither is the attribute as a whole, see below.
2795 Set_Must_Not_Freeze
(Last
(Expr_List
));
2800 -- Immediate error if too many formals. Other mismatches in number or
2801 -- types of parameters are detected when we analyze the body of the
2802 -- subprogram that we construct.
2804 if Form_Num
> 2 then
2805 Error_Msg_N
("too many formals for attribute", N
);
2807 -- Error if the attribute reference has expressions that look like
2808 -- formal parameters.
2810 elsif Present
(Expressions
(Nam
)) then
2811 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
2814 Aname
= Name_Compose
or else
2815 Aname
= Name_Exponent
or else
2816 Aname
= Name_Leading_Part
or else
2817 Aname
= Name_Pos
or else
2818 Aname
= Name_Round
or else
2819 Aname
= Name_Scaling
or else
2822 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
2823 and then Present
(Corresponding_Formal_Spec
(N
))
2826 ("generic actual cannot be attribute involving universal type",
2830 ("attribute involving a universal type cannot be renamed",
2835 -- AST_Entry is an odd case. It doesn't really make much sense to allow
2836 -- it to be renamed, but that's the DEC rule, so we have to do it right.
2837 -- The point is that the AST_Entry call should be made now, and what the
2838 -- function will return is the returned value.
2840 -- Note that there is no Expr_List in this case anyway
2842 if Aname
= Name_AST_Entry
then
2844 Ent
: constant Entity_Id
:= Make_Temporary
(Loc
, 'R', Nam
);
2849 Make_Object_Declaration
(Loc
,
2850 Defining_Identifier
=> Ent
,
2851 Object_Definition
=>
2852 New_Occurrence_Of
(RTE
(RE_AST_Handler
), Loc
),
2854 Constant_Present
=> True);
2856 Set_Assignment_OK
(Decl
, True);
2857 Insert_Action
(N
, Decl
);
2858 Attr_Node
:= Make_Identifier
(Loc
, Chars
(Ent
));
2861 -- For all other attributes, we rewrite the attribute node to have
2862 -- a list of expressions corresponding to the subprogram formals.
2863 -- A renaming declaration is not a freeze point, and the analysis of
2864 -- the attribute reference should not freeze the type of the prefix.
2868 Make_Attribute_Reference
(Loc
,
2869 Prefix
=> Prefix
(Nam
),
2870 Attribute_Name
=> Aname
,
2871 Expressions
=> Expr_List
);
2873 Set_Must_Not_Freeze
(Attr_Node
);
2874 Set_Must_Not_Freeze
(Prefix
(Nam
));
2877 -- Case of renaming a function
2879 if Nkind
(Spec
) = N_Function_Specification
then
2880 if Is_Procedure_Attribute_Name
(Aname
) then
2881 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
2885 Find_Type
(Result_Definition
(Spec
));
2886 Rewrite
(Result_Definition
(Spec
),
2888 Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
2891 Make_Subprogram_Body
(Loc
,
2892 Specification
=> Spec
,
2893 Declarations
=> New_List
,
2894 Handled_Statement_Sequence
=>
2895 Make_Handled_Sequence_Of_Statements
(Loc
,
2896 Statements
=> New_List
(
2897 Make_Simple_Return_Statement
(Loc
,
2898 Expression
=> Attr_Node
))));
2900 -- Case of renaming a procedure
2903 if not Is_Procedure_Attribute_Name
(Aname
) then
2904 Error_Msg_N
("attribute can only be renamed as function", Nam
);
2909 Make_Subprogram_Body
(Loc
,
2910 Specification
=> Spec
,
2911 Declarations
=> New_List
,
2912 Handled_Statement_Sequence
=>
2913 Make_Handled_Sequence_Of_Statements
(Loc
,
2914 Statements
=> New_List
(Attr_Node
)));
2917 -- In case of tagged types we add the body of the generated function to
2918 -- the freezing actions of the type (because in the general case such
2919 -- type is still not frozen). We exclude from this processing generic
2920 -- formal subprograms found in instantiations and AST_Entry renamings.
2922 if not Present
(Corresponding_Formal_Spec
(N
))
2923 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
2926 P
: constant Entity_Id
:= Prefix
(Nam
);
2931 if Is_Tagged_Type
(Etype
(P
)) then
2932 Ensure_Freeze_Node
(Etype
(P
));
2933 Append_Freeze_Action
(Etype
(P
), Body_Node
);
2935 Rewrite
(N
, Body_Node
);
2937 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
2941 -- Generic formal subprograms or AST_Handler renaming
2944 Rewrite
(N
, Body_Node
);
2946 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
2949 if Is_Compilation_Unit
(New_S
) then
2951 ("a library unit can only rename another library unit", N
);
2954 -- We suppress elaboration warnings for the resulting entity, since
2955 -- clearly they are not needed, and more particularly, in the case
2956 -- of a generic formal subprogram, the resulting entity can appear
2957 -- after the instantiation itself, and thus look like a bogus case
2958 -- of access before elaboration.
2960 Set_Suppress_Elaboration_Warnings
(New_S
);
2962 end Attribute_Renaming
;
2964 ----------------------
2965 -- Chain_Use_Clause --
2966 ----------------------
2968 procedure Chain_Use_Clause
(N
: Node_Id
) is
2970 Level
: Int
:= Scope_Stack
.Last
;
2973 if not Is_Compilation_Unit
(Current_Scope
)
2974 or else not Is_Child_Unit
(Current_Scope
)
2976 null; -- Common case
2978 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
2979 null; -- Common case for compilation unit
2982 -- If declaration appears in some other scope, it must be in some
2983 -- parent unit when compiling a child.
2985 Pack
:= Defining_Entity
(Parent
(N
));
2986 if not In_Open_Scopes
(Pack
) then
2987 null; -- default as well
2990 -- Find entry for parent unit in scope stack
2992 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
2998 Set_Next_Use_Clause
(N
,
2999 Scope_Stack
.Table
(Level
).First_Use_Clause
);
3000 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
3001 end Chain_Use_Clause
;
3003 ---------------------------
3004 -- Check_Frozen_Renaming --
3005 ---------------------------
3007 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
3013 and then not Has_Completion
(Subp
)
3017 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
3019 if Is_Entity_Name
(Name
(N
)) then
3020 Old_S
:= Entity
(Name
(N
));
3022 if not Is_Frozen
(Old_S
)
3023 and then Operating_Mode
/= Check_Semantics
3025 Append_Freeze_Action
(Old_S
, B_Node
);
3027 Insert_After
(N
, B_Node
);
3031 if Is_Intrinsic_Subprogram
(Old_S
)
3032 and then not In_Instance
3035 ("subprogram used in renaming_as_body cannot be intrinsic",
3040 Insert_After
(N
, B_Node
);
3044 end Check_Frozen_Renaming
;
3046 -------------------------------
3047 -- Set_Entity_Or_Discriminal --
3048 -------------------------------
3050 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
3054 -- If the entity is not a discriminant, or else expansion is disabled,
3055 -- simply set the entity.
3057 if not In_Spec_Expression
3058 or else Ekind
(E
) /= E_Discriminant
3059 or else Inside_A_Generic
3061 Set_Entity_With_Style_Check
(N
, E
);
3063 -- The replacement of a discriminant by the corresponding discriminal
3064 -- is not done for a task discriminant that appears in a default
3065 -- expression of an entry parameter. See Expand_Discriminant in exp_ch2
3066 -- for details on their handling.
3068 elsif Is_Concurrent_Type
(Scope
(E
)) then
3072 and then not Nkind_In
(P
, N_Parameter_Specification
,
3073 N_Component_Declaration
)
3079 and then Nkind
(P
) = N_Parameter_Specification
3084 Set_Entity
(N
, Discriminal
(E
));
3087 -- Otherwise, this is a discriminant in a context in which
3088 -- it is a reference to the corresponding parameter of the
3089 -- init proc for the enclosing type.
3092 Set_Entity
(N
, Discriminal
(E
));
3094 end Set_Entity_Or_Discriminal
;
3096 -----------------------------------
3097 -- Check_In_Previous_With_Clause --
3098 -----------------------------------
3100 procedure Check_In_Previous_With_Clause
3104 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
3109 Item
:= First
(Context_Items
(Parent
(N
)));
3111 while Present
(Item
)
3114 if Nkind
(Item
) = N_With_Clause
3116 -- Protect the frontend against previous critical errors
3118 and then Nkind
(Name
(Item
)) /= N_Selected_Component
3119 and then Entity
(Name
(Item
)) = Pack
3123 -- Find root library unit in with_clause
3125 while Nkind
(Par
) = N_Expanded_Name
loop
3126 Par
:= Prefix
(Par
);
3129 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
3130 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
3139 -- On exit, package is not mentioned in a previous with_clause.
3140 -- Check if its prefix is.
3142 if Nkind
(Nam
) = N_Expanded_Name
then
3143 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
3145 elsif Pack
/= Any_Id
then
3146 Error_Msg_NE
("& is not visible", Nam
, Pack
);
3148 end Check_In_Previous_With_Clause
;
3150 ---------------------------------
3151 -- Check_Library_Unit_Renaming --
3152 ---------------------------------
3154 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
3158 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3161 -- Check for library unit. Note that we used to check for the scope
3162 -- being Standard here, but that was wrong for Standard itself.
3164 elsif not Is_Compilation_Unit
(Old_E
)
3165 and then not Is_Child_Unit
(Old_E
)
3167 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
3169 -- Entities defined in Standard (operators and boolean literals) cannot
3170 -- be renamed as library units.
3172 elsif Scope
(Old_E
) = Standard_Standard
3173 and then Sloc
(Old_E
) = Standard_Location
3175 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
3177 elsif Present
(Parent_Spec
(N
))
3178 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
3179 and then not Is_Child_Unit
(Old_E
)
3182 ("renamed unit must be a child unit of generic parent", Name
(N
));
3184 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
3185 and then Nkind
(Name
(N
)) = N_Expanded_Name
3186 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
3187 and then Is_Generic_Unit
(Old_E
)
3190 ("renamed generic unit must be a library unit", Name
(N
));
3192 elsif Is_Package_Or_Generic_Package
(Old_E
) then
3194 -- Inherit categorization flags
3196 New_E
:= Defining_Entity
(N
);
3197 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
3198 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
3199 Set_Is_Remote_Call_Interface
(New_E
,
3200 Is_Remote_Call_Interface
(Old_E
));
3201 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
3202 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
3204 end Check_Library_Unit_Renaming
;
3210 procedure End_Scope
is
3216 Id
:= First_Entity
(Current_Scope
);
3217 while Present
(Id
) loop
3218 -- An entity in the current scope is not necessarily the first one
3219 -- on its homonym chain. Find its predecessor if any,
3220 -- If it is an internal entity, it will not be in the visibility
3221 -- chain altogether, and there is nothing to unchain.
3223 if Id
/= Current_Entity
(Id
) then
3224 Prev
:= Current_Entity
(Id
);
3225 while Present
(Prev
)
3226 and then Present
(Homonym
(Prev
))
3227 and then Homonym
(Prev
) /= Id
3229 Prev
:= Homonym
(Prev
);
3232 -- Skip to end of loop if Id is not in the visibility chain
3234 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
3242 Set_Is_Immediately_Visible
(Id
, False);
3244 Outer
:= Homonym
(Id
);
3245 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
3246 Outer
:= Homonym
(Outer
);
3249 -- Reset homonym link of other entities, but do not modify link
3250 -- between entities in current scope, so that the back-end can have
3251 -- a proper count of local overloadings.
3254 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
3256 elsif Scope
(Prev
) /= Scope
(Id
) then
3257 Set_Homonym
(Prev
, Outer
);
3264 -- If the scope generated freeze actions, place them before the
3265 -- current declaration and analyze them. Type declarations and
3266 -- the bodies of initialization procedures can generate such nodes.
3267 -- We follow the parent chain until we reach a list node, which is
3268 -- the enclosing list of declarations. If the list appears within
3269 -- a protected definition, move freeze nodes outside the protected
3273 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
3277 L
: constant List_Id
:= Scope_Stack
.Table
3278 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
3281 if Is_Itype
(Current_Scope
) then
3282 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
3284 Decl
:= Parent
(Current_Scope
);
3289 while not (Is_List_Member
(Decl
))
3290 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
3293 Decl
:= Parent
(Decl
);
3296 Insert_List_Before_And_Analyze
(Decl
, L
);
3305 ---------------------
3306 -- End_Use_Clauses --
3307 ---------------------
3309 procedure End_Use_Clauses
(Clause
: Node_Id
) is
3313 -- Remove Use_Type clauses first, because they affect the
3314 -- visibility of operators in subsequent used packages.
3317 while Present
(U
) loop
3318 if Nkind
(U
) = N_Use_Type_Clause
then
3322 Next_Use_Clause
(U
);
3326 while Present
(U
) loop
3327 if Nkind
(U
) = N_Use_Package_Clause
then
3328 End_Use_Package
(U
);
3331 Next_Use_Clause
(U
);
3333 end End_Use_Clauses
;
3335 ---------------------
3336 -- End_Use_Package --
3337 ---------------------
3339 procedure End_Use_Package
(N
: Node_Id
) is
3340 Pack_Name
: Node_Id
;
3345 function Is_Primitive_Operator
3347 F
: Entity_Id
) return Boolean;
3348 -- Check whether Op is a primitive operator of a use-visible type
3350 ---------------------------
3351 -- Is_Primitive_Operator --
3352 ---------------------------
3354 function Is_Primitive_Operator
3356 F
: Entity_Id
) return Boolean
3358 T
: constant Entity_Id
:= Etype
(F
);
3361 and then Scope
(T
) = Scope
(Op
);
3362 end Is_Primitive_Operator
;
3364 -- Start of processing for End_Use_Package
3367 Pack_Name
:= First
(Names
(N
));
3368 while Present
(Pack_Name
) loop
3370 -- Test that Pack_Name actually denotes a package before processing
3372 if Is_Entity_Name
(Pack_Name
)
3373 and then Ekind
(Entity
(Pack_Name
)) = E_Package
3375 Pack
:= Entity
(Pack_Name
);
3377 if In_Open_Scopes
(Pack
) then
3380 elsif not Redundant_Use
(Pack_Name
) then
3381 Set_In_Use
(Pack
, False);
3382 Set_Current_Use_Clause
(Pack
, Empty
);
3384 Id
:= First_Entity
(Pack
);
3385 while Present
(Id
) loop
3387 -- Preserve use-visibility of operators that are primitive
3388 -- operators of a type that is use-visible through an active
3391 if Nkind
(Id
) = N_Defining_Operator_Symbol
3393 (Is_Primitive_Operator
(Id
, First_Formal
(Id
))
3395 (Present
(Next_Formal
(First_Formal
(Id
)))
3397 Is_Primitive_Operator
3398 (Id
, Next_Formal
(First_Formal
(Id
)))))
3403 Set_Is_Potentially_Use_Visible
(Id
, False);
3406 if Is_Private_Type
(Id
)
3407 and then Present
(Full_View
(Id
))
3409 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
3415 if Present
(Renamed_Object
(Pack
)) then
3416 Set_In_Use
(Renamed_Object
(Pack
), False);
3417 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
3420 if Chars
(Pack
) = Name_System
3421 and then Scope
(Pack
) = Standard_Standard
3422 and then Present_System_Aux
3424 Id
:= First_Entity
(System_Aux_Id
);
3425 while Present
(Id
) loop
3426 Set_Is_Potentially_Use_Visible
(Id
, False);
3428 if Is_Private_Type
(Id
)
3429 and then Present
(Full_View
(Id
))
3431 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
3437 Set_In_Use
(System_Aux_Id
, False);
3441 Set_Redundant_Use
(Pack_Name
, False);
3448 if Present
(Hidden_By_Use_Clause
(N
)) then
3449 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
3450 while Present
(Elmt
) loop
3452 E
: constant Entity_Id
:= Node
(Elmt
);
3455 -- Reset either Use_Visibility or Direct_Visibility, depending
3456 -- on how the entity was hidden by the use clause.
3458 if In_Use
(Scope
(E
))
3459 and then Used_As_Generic_Actual
(Scope
(E
))
3461 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3463 Set_Is_Immediately_Visible
(Node
(Elmt
));
3470 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3472 end End_Use_Package
;
3478 procedure End_Use_Type
(N
: Node_Id
) is
3485 function May_Be_Used_Primitive_Of
(T
: Entity_Id
) return Boolean;
3486 -- An operator may be primitive in several types, if they are declared
3487 -- in the same scope as the operator. To determine the use-visiblity of
3488 -- the operator in such cases we must examine all types in the profile.
3490 ------------------------------
3491 -- May_Be_Used_Primitive_Of --
3492 ------------------------------
3494 function May_Be_Used_Primitive_Of
(T
: Entity_Id
) return Boolean is
3496 return Scope
(Op
) = Scope
(T
)
3497 and then (In_Use
(T
) or else Is_Potentially_Use_Visible
(T
));
3498 end May_Be_Used_Primitive_Of
;
3500 -- Start of processing for End_Use_Type
3503 Id
:= First
(Subtype_Marks
(N
));
3504 while Present
(Id
) loop
3506 -- A call to Rtsfind may occur while analyzing a use_type clause,
3507 -- in which case the type marks are not resolved yet, and there is
3508 -- nothing to remove.
3510 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
3516 if T
= Any_Type
or else From_With_Type
(T
) then
3519 -- Note that the use_type clause may mention a subtype of the type
3520 -- whose primitive operations have been made visible. Here as
3521 -- elsewhere, it is the base type that matters for visibility.
3523 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
3526 elsif not Redundant_Use
(Id
) then
3527 Set_In_Use
(T
, False);
3528 Set_In_Use
(Base_Type
(T
), False);
3529 Set_Current_Use_Clause
(T
, Empty
);
3530 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
3531 Op_List
:= Collect_Primitive_Operations
(T
);
3533 Elmt
:= First_Elmt
(Op_List
);
3534 while Present
(Elmt
) loop
3537 if Nkind
(Op
) = N_Defining_Operator_Symbol
then
3539 T_First
: constant Entity_Id
:=
3540 Base_Type
(Etype
(First_Formal
(Op
)));
3541 T_Res
: constant Entity_Id
:= Base_Type
(Etype
(Op
));
3545 if Present
(Next_Formal
(First_Formal
(Op
))) then
3547 Base_Type
(Etype
(Next_Formal
(First_Formal
(Op
))));
3552 if not May_Be_Used_Primitive_Of
(T_First
)
3553 and then not May_Be_Used_Primitive_Of
(T_Next
)
3554 and then not May_Be_Used_Primitive_Of
(T_Res
)
3556 Set_Is_Potentially_Use_Visible
(Op
, False);
3570 ----------------------
3571 -- Find_Direct_Name --
3572 ----------------------
3574 procedure Find_Direct_Name
(N
: Node_Id
) is
3579 Inst
: Entity_Id
:= Empty
;
3580 -- Enclosing instance, if any
3582 Homonyms
: Entity_Id
;
3583 -- Saves start of homonym chain
3585 Nvis_Entity
: Boolean;
3586 -- Set True to indicate that there is at least one entity on the homonym
3587 -- chain which, while not visible, is visible enough from the user point
3588 -- of view to warrant an error message of "not visible" rather than
3591 Nvis_Is_Private_Subprg
: Boolean := False;
3592 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
3593 -- effect concerning library subprograms has been detected. Used to
3594 -- generate the precise error message.
3596 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
3597 -- Returns true if the entity is declared in a package that is
3598 -- an actual for a formal package of the current instance. Such an
3599 -- entity requires special handling because it may be use-visible
3600 -- but hides directly visible entities defined outside the instance.
3602 function Is_Actual_Parameter
return Boolean;
3603 -- This function checks if the node N is an identifier that is an actual
3604 -- parameter of a procedure call. If so it returns True, otherwise it
3605 -- return False. The reason for this check is that at this stage we do
3606 -- not know what procedure is being called if the procedure might be
3607 -- overloaded, so it is premature to go setting referenced flags or
3608 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
3609 -- for that processing
3611 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
3612 -- This function determines whether the entity E (which is not
3613 -- visible) can reasonably be considered to be known to the writer
3614 -- of the reference. This is a heuristic test, used only for the
3615 -- purposes of figuring out whether we prefer to complain that an
3616 -- entity is undefined or invisible (and identify the declaration
3617 -- of the invisible entity in the latter case). The point here is
3618 -- that we don't want to complain that something is invisible and
3619 -- then point to something entirely mysterious to the writer.
3621 procedure Nvis_Messages
;
3622 -- Called if there are no visible entries for N, but there is at least
3623 -- one non-directly visible, or hidden declaration. This procedure
3624 -- outputs an appropriate set of error messages.
3626 procedure Undefined
(Nvis
: Boolean);
3627 -- This function is called if the current node has no corresponding
3628 -- visible entity or entities. The value set in Msg indicates whether
3629 -- an error message was generated (multiple error messages for the
3630 -- same variable are generally suppressed, see body for details).
3631 -- Msg is True if an error message was generated, False if not. This
3632 -- value is used by the caller to determine whether or not to output
3633 -- additional messages where appropriate. The parameter is set False
3634 -- to get the message "X is undefined", and True to get the message
3635 -- "X is not visible".
3637 -------------------------
3638 -- From_Actual_Package --
3639 -------------------------
3641 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
3642 Scop
: constant Entity_Id
:= Scope
(E
);
3646 if not In_Instance
then
3649 Inst
:= Current_Scope
;
3650 while Present
(Inst
)
3651 and then Ekind
(Inst
) /= E_Package
3652 and then not Is_Generic_Instance
(Inst
)
3654 Inst
:= Scope
(Inst
);
3661 Act
:= First_Entity
(Inst
);
3662 while Present
(Act
) loop
3663 if Ekind
(Act
) = E_Package
then
3665 -- Check for end of actuals list
3667 if Renamed_Object
(Act
) = Inst
then
3670 elsif Present
(Associated_Formal_Package
(Act
))
3671 and then Renamed_Object
(Act
) = Scop
3673 -- Entity comes from (instance of) formal package
3688 end From_Actual_Package
;
3690 -------------------------
3691 -- Is_Actual_Parameter --
3692 -------------------------
3694 function Is_Actual_Parameter
return Boolean is
3697 Nkind
(N
) = N_Identifier
3699 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
3701 (Nkind
(Parent
(N
)) = N_Parameter_Association
3702 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
3703 and then Nkind
(Parent
(Parent
(N
))) =
3704 N_Procedure_Call_Statement
));
3705 end Is_Actual_Parameter
;
3707 -------------------------
3708 -- Known_But_Invisible --
3709 -------------------------
3711 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
3712 Fname
: File_Name_Type
;
3715 -- Entities in Standard are always considered to be known
3717 if Sloc
(E
) <= Standard_Location
then
3720 -- An entity that does not come from source is always considered
3721 -- to be unknown, since it is an artifact of code expansion.
3723 elsif not Comes_From_Source
(E
) then
3726 -- In gnat internal mode, we consider all entities known
3728 elsif GNAT_Mode
then
3732 -- Here we have an entity that is not from package Standard, and
3733 -- which comes from Source. See if it comes from an internal file.
3735 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
3737 -- Case of from internal file
3739 if Is_Internal_File_Name
(Fname
) then
3741 -- Private part entities in internal files are never considered
3742 -- to be known to the writer of normal application code.
3744 if Is_Hidden
(E
) then
3748 -- Entities from System packages other than System and
3749 -- System.Storage_Elements are not considered to be known.
3750 -- System.Auxxxx files are also considered known to the user.
3752 -- Should refine this at some point to generally distinguish
3753 -- between known and unknown internal files ???
3755 Get_Name_String
(Fname
);
3760 Name_Buffer
(1 .. 2) /= "s-"
3762 Name_Buffer
(3 .. 8) = "stoele"
3764 Name_Buffer
(3 .. 5) = "aux";
3766 -- If not an internal file, then entity is definitely known,
3767 -- even if it is in a private part (the message generated will
3768 -- note that it is in a private part)
3773 end Known_But_Invisible
;
3779 procedure Nvis_Messages
is
3780 Comp_Unit
: Node_Id
;
3782 Found
: Boolean := False;
3783 Hidden
: Boolean := False;
3787 -- Ada 2005 (AI-262): Generate a precise error concerning the
3788 -- Beaujolais effect that was previously detected
3790 if Nvis_Is_Private_Subprg
then
3792 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
3793 and then Ekind
(E2
) = E_Function
3794 and then Scope
(E2
) = Standard_Standard
3795 and then Has_Private_With
(E2
));
3797 -- Find the sloc corresponding to the private with'ed unit
3799 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
3800 Error_Msg_Sloc
:= No_Location
;
3802 Item
:= First
(Context_Items
(Comp_Unit
));
3803 while Present
(Item
) loop
3804 if Nkind
(Item
) = N_With_Clause
3805 and then Private_Present
(Item
)
3806 and then Entity
(Name
(Item
)) = E2
3808 Error_Msg_Sloc
:= Sloc
(Item
);
3815 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
3817 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
3821 Undefined
(Nvis
=> True);
3825 -- First loop does hidden declarations
3828 while Present
(Ent
) loop
3829 if Is_Potentially_Use_Visible
(Ent
) then
3831 Error_Msg_N
-- CODEFIX
3832 ("multiple use clauses cause hiding!", N
);
3836 Error_Msg_Sloc
:= Sloc
(Ent
);
3837 Error_Msg_N
-- CODEFIX
3838 ("hidden declaration#!", N
);
3841 Ent
:= Homonym
(Ent
);
3844 -- If we found hidden declarations, then that's enough, don't
3845 -- bother looking for non-visible declarations as well.
3851 -- Second loop does non-directly visible declarations
3854 while Present
(Ent
) loop
3855 if not Is_Potentially_Use_Visible
(Ent
) then
3857 -- Do not bother the user with unknown entities
3859 if not Known_But_Invisible
(Ent
) then
3863 Error_Msg_Sloc
:= Sloc
(Ent
);
3865 -- Output message noting that there is a non-visible
3866 -- declaration, distinguishing the private part case.
3868 if Is_Hidden
(Ent
) then
3869 Error_Msg_N
("non-visible (private) declaration#!", N
);
3871 -- If the entity is declared in a generic package, it
3872 -- cannot be visible, so there is no point in adding it
3873 -- to the list of candidates if another homograph from a
3874 -- non-generic package has been seen.
3876 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
3882 Error_Msg_N
-- CODEFIX
3883 ("non-visible declaration#!", N
);
3885 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
3889 if Is_Compilation_Unit
(Ent
)
3891 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
3893 Error_Msg_Qual_Level
:= 99;
3894 Error_Msg_NE
-- CODEFIX
3895 ("\\missing `WITH &;`", N
, Ent
);
3896 Error_Msg_Qual_Level
:= 0;
3899 if Ekind
(Ent
) = E_Discriminant
3900 and then Present
(Corresponding_Discriminant
(Ent
))
3901 and then Scope
(Corresponding_Discriminant
(Ent
)) =
3905 ("inherited discriminant not allowed here" &
3906 " (RM 3.8 (12), 3.8.1 (6))!", N
);
3910 -- Set entity and its containing package as referenced. We
3911 -- can't be sure of this, but this seems a better choice
3912 -- to avoid unused entity messages.
3914 if Comes_From_Source
(Ent
) then
3915 Set_Referenced
(Ent
);
3916 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
3921 Ent
:= Homonym
(Ent
);
3930 procedure Undefined
(Nvis
: Boolean) is
3931 Emsg
: Error_Msg_Id
;
3934 -- We should never find an undefined internal name. If we do, then
3935 -- see if we have previous errors. If so, ignore on the grounds that
3936 -- it is probably a cascaded message (e.g. a block label from a badly
3937 -- formed block). If no previous errors, then we have a real internal
3938 -- error of some kind so raise an exception.
3940 if Is_Internal_Name
(Chars
(N
)) then
3941 if Total_Errors_Detected
/= 0 then
3944 raise Program_Error
;
3948 -- A very specialized error check, if the undefined variable is
3949 -- a case tag, and the case type is an enumeration type, check
3950 -- for a possible misspelling, and if so, modify the identifier
3952 -- Named aggregate should also be handled similarly ???
3954 if Nkind
(N
) = N_Identifier
3955 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
3958 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
3959 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
3964 if Is_Enumeration_Type
(Case_Typ
)
3965 and then not Is_Standard_Character_Type
(Case_Typ
)
3967 Lit
:= First_Literal
(Case_Typ
);
3968 Get_Name_String
(Chars
(Lit
));
3970 if Chars
(Lit
) /= Chars
(N
)
3971 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
)) then
3972 Error_Msg_Node_2
:= Lit
;
3973 Error_Msg_N
-- CODEFIX
3974 ("& is undefined, assume misspelling of &", N
);
3975 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
3979 Lit
:= Next_Literal
(Lit
);
3984 -- Normal processing
3986 Set_Entity
(N
, Any_Id
);
3987 Set_Etype
(N
, Any_Type
);
3989 -- We use the table Urefs to keep track of entities for which we
3990 -- have issued errors for undefined references. Multiple errors
3991 -- for a single name are normally suppressed, however we modify
3992 -- the error message to alert the programmer to this effect.
3994 for J
in Urefs
.First
.. Urefs
.Last
loop
3995 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
3996 if Urefs
.Table
(J
).Err
/= No_Error_Msg
3997 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
3999 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
4001 if Urefs
.Table
(J
).Nvis
then
4002 Change_Error_Text
(Urefs
.Table
(J
).Err
,
4003 "& is not visible (more references follow)");
4005 Change_Error_Text
(Urefs
.Table
(J
).Err
,
4006 "& is undefined (more references follow)");
4009 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
4012 -- Although we will set Msg False, and thus suppress the
4013 -- message, we also set Error_Posted True, to avoid any
4014 -- cascaded messages resulting from the undefined reference.
4017 Set_Error_Posted
(N
, True);
4022 -- If entry not found, this is first undefined occurrence
4025 Error_Msg_N
("& is not visible!", N
);
4029 Error_Msg_N
("& is undefined!", N
);
4032 -- A very bizarre special check, if the undefined identifier
4033 -- is put or put_line, then add a special error message (since
4034 -- this is a very common error for beginners to make).
4036 if Chars
(N
) = Name_Put
or else Chars
(N
) = Name_Put_Line
then
4037 Error_Msg_N
-- CODEFIX
4038 ("\\possible missing `WITH Ada.Text_'I'O; " &
4039 "USE Ada.Text_'I'O`!", N
);
4041 -- Another special check if N is the prefix of a selected
4042 -- component which is a known unit, add message complaining
4043 -- about missing with for this unit.
4045 elsif Nkind
(Parent
(N
)) = N_Selected_Component
4046 and then N
= Prefix
(Parent
(N
))
4047 and then Is_Known_Unit
(Parent
(N
))
4049 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
4050 Error_Msg_N
-- CODEFIX
4051 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
4054 -- Now check for possible misspellings
4058 Ematch
: Entity_Id
:= Empty
;
4060 Last_Name_Id
: constant Name_Id
:=
4061 Name_Id
(Nat
(First_Name_Id
) +
4062 Name_Entries_Count
- 1);
4065 for Nam
in First_Name_Id
.. Last_Name_Id
loop
4066 E
:= Get_Name_Entity_Id
(Nam
);
4069 and then (Is_Immediately_Visible
(E
)
4071 Is_Potentially_Use_Visible
(E
))
4073 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
4080 if Present
(Ematch
) then
4081 Error_Msg_NE
-- CODEFIX
4082 ("\possible misspelling of&", N
, Ematch
);
4087 -- Make entry in undefined references table unless the full errors
4088 -- switch is set, in which case by refraining from generating the
4089 -- table entry, we guarantee that we get an error message for every
4090 -- undefined reference.
4092 if not All_Errors_Mode
then
4103 -- Start of processing for Find_Direct_Name
4106 -- If the entity pointer is already set, this is an internal node, or
4107 -- a node that is analyzed more than once, after a tree modification.
4108 -- In such a case there is no resolution to perform, just set the type.
4110 if Present
(Entity
(N
)) then
4111 if Is_Type
(Entity
(N
)) then
4112 Set_Etype
(N
, Entity
(N
));
4116 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
4119 -- One special case here. If the Etype field is already set,
4120 -- and references the packed array type corresponding to the
4121 -- etype of the referenced entity, then leave it alone. This
4122 -- happens for trees generated from Exp_Pakd, where expressions
4123 -- can be deliberately "mis-typed" to the packed array type.
4125 if Is_Array_Type
(Entyp
)
4126 and then Is_Packed
(Entyp
)
4127 and then Present
(Etype
(N
))
4128 and then Etype
(N
) = Packed_Array_Type
(Entyp
)
4132 -- If not that special case, then just reset the Etype
4135 Set_Etype
(N
, Etype
(Entity
(N
)));
4143 -- Here if Entity pointer was not set, we need full visibility analysis
4144 -- First we generate debugging output if the debug E flag is set.
4146 if Debug_Flag_E
then
4147 Write_Str
("Looking for ");
4148 Write_Name
(Chars
(N
));
4152 Homonyms
:= Current_Entity
(N
);
4153 Nvis_Entity
:= False;
4156 while Present
(E
) loop
4158 -- If entity is immediately visible or potentially use visible, then
4159 -- process the entity and we are done.
4161 if Is_Immediately_Visible
(E
) then
4162 goto Immediately_Visible_Entity
;
4164 elsif Is_Potentially_Use_Visible
(E
) then
4165 goto Potentially_Use_Visible_Entity
;
4167 -- Note if a known but invisible entity encountered
4169 elsif Known_But_Invisible
(E
) then
4170 Nvis_Entity
:= True;
4173 -- Move to next entity in chain and continue search
4178 -- If no entries on homonym chain that were potentially visible,
4179 -- and no entities reasonably considered as non-visible, then
4180 -- we have a plain undefined reference, with no additional
4181 -- explanation required!
4183 if not Nvis_Entity
then
4184 Undefined
(Nvis
=> False);
4186 -- Otherwise there is at least one entry on the homonym chain that
4187 -- is reasonably considered as being known and non-visible.
4195 -- Processing for a potentially use visible entry found. We must search
4196 -- the rest of the homonym chain for two reasons. First, if there is a
4197 -- directly visible entry, then none of the potentially use-visible
4198 -- entities are directly visible (RM 8.4(10)). Second, we need to check
4199 -- for the case of multiple potentially use-visible entries hiding one
4200 -- another and as a result being non-directly visible (RM 8.4(11)).
4202 <<Potentially_Use_Visible_Entity
>> declare
4203 Only_One_Visible
: Boolean := True;
4204 All_Overloadable
: Boolean := Is_Overloadable
(E
);
4208 while Present
(E2
) loop
4209 if Is_Immediately_Visible
(E2
) then
4211 -- If the use-visible entity comes from the actual for a
4212 -- formal package, it hides a directly visible entity from
4213 -- outside the instance.
4215 if From_Actual_Package
(E
)
4216 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
4221 goto Immediately_Visible_Entity
;
4224 elsif Is_Potentially_Use_Visible
(E2
) then
4225 Only_One_Visible
:= False;
4226 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
4228 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
4229 -- that can occur in private_with clauses. Example:
4232 -- private with B; package A is
4233 -- package C is function B return Integer;
4235 -- V1 : Integer := B;
4236 -- private function B return Integer;
4237 -- V2 : Integer := B;
4240 -- V1 resolves to A.B, but V2 resolves to library unit B
4242 elsif Ekind
(E2
) = E_Function
4243 and then Scope
(E2
) = Standard_Standard
4244 and then Has_Private_With
(E2
)
4246 Only_One_Visible
:= False;
4247 All_Overloadable
:= False;
4248 Nvis_Is_Private_Subprg
:= True;
4255 -- On falling through this loop, we have checked that there are no
4256 -- immediately visible entities. Only_One_Visible is set if exactly
4257 -- one potentially use visible entity exists. All_Overloadable is
4258 -- set if all the potentially use visible entities are overloadable.
4259 -- The condition for legality is that either there is one potentially
4260 -- use visible entity, or if there is more than one, then all of them
4261 -- are overloadable.
4263 if Only_One_Visible
or All_Overloadable
then
4266 -- If there is more than one potentially use-visible entity and at
4267 -- least one of them non-overloadable, we have an error (RM 8.4(11).
4268 -- Note that E points to the first such entity on the homonym list.
4269 -- Special case: if one of the entities is declared in an actual
4270 -- package, it was visible in the generic, and takes precedence over
4271 -- other entities that are potentially use-visible. Same if it is
4272 -- declared in a local instantiation of the current instance.
4277 -- Find current instance
4279 Inst
:= Current_Scope
;
4280 while Present
(Inst
)
4281 and then Inst
/= Standard_Standard
4283 if Is_Generic_Instance
(Inst
) then
4287 Inst
:= Scope
(Inst
);
4291 while Present
(E2
) loop
4292 if From_Actual_Package
(E2
)
4294 (Is_Generic_Instance
(Scope
(E2
))
4295 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
4308 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
4310 -- A use-clause in the body of a system file creates conflict
4311 -- with some entity in a user scope, while rtsfind is active.
4312 -- Keep only the entity coming from another predefined unit.
4315 while Present
(E2
) loop
4316 if Is_Predefined_File_Name
4317 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
4326 -- Entity must exist because predefined unit is correct
4328 raise Program_Error
;
4337 -- Come here with E set to the first immediately visible entity on
4338 -- the homonym chain. This is the one we want unless there is another
4339 -- immediately visible entity further on in the chain for an inner
4340 -- scope (RM 8.3(8)).
4342 <<Immediately_Visible_Entity
>> declare
4347 -- Find scope level of initial entity. When compiling through
4348 -- Rtsfind, the previous context is not completely invisible, and
4349 -- an outer entity may appear on the chain, whose scope is below
4350 -- the entry for Standard that delimits the current scope stack.
4351 -- Indicate that the level for this spurious entry is outside of
4352 -- the current scope stack.
4354 Level
:= Scope_Stack
.Last
;
4356 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
4357 exit when Scop
= Scope
(E
);
4359 exit when Scop
= Standard_Standard
;
4362 -- Now search remainder of homonym chain for more inner entry
4363 -- If the entity is Standard itself, it has no scope, and we
4364 -- compare it with the stack entry directly.
4367 while Present
(E2
) loop
4368 if Is_Immediately_Visible
(E2
) then
4370 -- If a generic package contains a local declaration that
4371 -- has the same name as the generic, there may be a visibility
4372 -- conflict in an instance, where the local declaration must
4373 -- also hide the name of the corresponding package renaming.
4374 -- We check explicitly for a package declared by a renaming,
4375 -- whose renamed entity is an instance that is on the scope
4376 -- stack, and that contains a homonym in the same scope. Once
4377 -- we have found it, we know that the package renaming is not
4378 -- immediately visible, and that the identifier denotes the
4379 -- other entity (and its homonyms if overloaded).
4381 if Scope
(E
) = Scope
(E2
)
4382 and then Ekind
(E
) = E_Package
4383 and then Present
(Renamed_Object
(E
))
4384 and then Is_Generic_Instance
(Renamed_Object
(E
))
4385 and then In_Open_Scopes
(Renamed_Object
(E
))
4386 and then Comes_From_Source
(N
)
4388 Set_Is_Immediately_Visible
(E
, False);
4392 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
4393 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
4394 or else Scope_Stack
.Table
(J
).Entity
= E2
4407 -- At the end of that loop, E is the innermost immediately
4408 -- visible entity, so we are all set.
4411 -- Come here with entity found, and stored in E
4415 -- Check violation of No_Wide_Characters restriction
4417 Check_Wide_Character_Restriction
(E
, N
);
4419 -- When distribution features are available (Get_PCS_Name /=
4420 -- Name_No_DSA), a remote access-to-subprogram type is converted
4421 -- into a record type holding whatever information is needed to
4422 -- perform a remote call on an RCI subprogram. In that case we
4423 -- rewrite any occurrence of the RAS type into the equivalent record
4424 -- type here. 'Access attribute references and RAS dereferences are
4425 -- then implemented using specific TSSs. However when distribution is
4426 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
4427 -- generation of these TSSs, and we must keep the RAS type in its
4428 -- original access-to-subprogram form (since all calls through a
4429 -- value of such type will be local anyway in the absence of a PCS).
4431 if Comes_From_Source
(N
)
4432 and then Is_Remote_Access_To_Subprogram_Type
(E
)
4433 and then Expander_Active
4434 and then Get_PCS_Name
/= Name_No_DSA
4437 New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
4441 -- Set the entity. Note that the reason we call Set_Entity for the
4442 -- overloadable case, as opposed to Set_Entity_With_Style_Check is
4443 -- that in the overloaded case, the initial call can set the wrong
4444 -- homonym. The call that sets the right homonym is in Sem_Res and
4445 -- that call does use Set_Entity_With_Style_Check, so we don't miss
4448 if Is_Overloadable
(E
) then
4451 Set_Entity_With_Style_Check
(N
, E
);
4457 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
4460 if Debug_Flag_E
then
4461 Write_Str
(" found ");
4462 Write_Entity_Info
(E
, " ");
4465 -- If the Ekind of the entity is Void, it means that all homonyms
4466 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
4467 -- test is skipped if the current scope is a record and the name is
4468 -- a pragma argument expression (case of Atomic and Volatile pragmas
4469 -- and possibly other similar pragmas added later, which are allowed
4470 -- to reference components in the current record).
4472 if Ekind
(E
) = E_Void
4474 (not Is_Record_Type
(Current_Scope
)
4475 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
4477 Premature_Usage
(N
);
4479 -- If the entity is overloadable, collect all interpretations of the
4480 -- name for subsequent overload resolution. We optimize a bit here to
4481 -- do this only if we have an overloadable entity that is not on its
4482 -- own on the homonym chain.
4484 elsif Is_Overloadable
(E
)
4485 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
4487 Collect_Interps
(N
);
4489 -- If no homonyms were visible, the entity is unambiguous
4491 if not Is_Overloaded
(N
) then
4492 if not Is_Actual_Parameter
then
4493 Generate_Reference
(E
, N
);
4497 -- Case of non-overloadable entity, set the entity providing that
4498 -- we do not have the case of a discriminant reference within a
4499 -- default expression. Such references are replaced with the
4500 -- corresponding discriminal, which is the formal corresponding to
4501 -- to the discriminant in the initialization procedure.
4504 -- Entity is unambiguous, indicate that it is referenced here
4506 -- For a renaming of an object, always generate simple reference,
4507 -- we don't try to keep track of assignments in this case.
4509 if Is_Object
(E
) and then Present
(Renamed_Object
(E
)) then
4510 Generate_Reference
(E
, N
);
4512 -- If the renamed entity is a private protected component,
4513 -- reference the original component as well. This needs to be
4514 -- done because the private renamings are installed before any
4515 -- analysis has occurred. Reference to a private component will
4516 -- resolve to the renaming and the original component will be
4517 -- left unreferenced, hence the following.
4519 if Is_Prival
(E
) then
4520 Generate_Reference
(Prival_Link
(E
), N
);
4523 -- One odd case is that we do not want to set the Referenced flag
4524 -- if the entity is a label, and the identifier is the label in
4525 -- the source, since this is not a reference from the point of
4526 -- view of the user.
4528 elsif Nkind
(Parent
(N
)) = N_Label
then
4530 R
: constant Boolean := Referenced
(E
);
4533 -- Generate reference unless this is an actual parameter
4534 -- (see comment below)
4536 if Is_Actual_Parameter
then
4537 Generate_Reference
(E
, N
);
4538 Set_Referenced
(E
, R
);
4542 -- Normal case, not a label: generate reference
4544 -- ??? It is too early to generate a reference here even if
4545 -- the entity is unambiguous, because the tree is not
4546 -- sufficiently typed at this point for Generate_Reference to
4547 -- determine whether this reference modifies the denoted object
4548 -- (because implicit dereferences cannot be identified prior to
4549 -- full type resolution).
4551 -- The Is_Actual_Parameter routine takes care of one of these
4552 -- cases but there are others probably ???
4555 if not Is_Actual_Parameter
then
4556 Generate_Reference
(E
, N
);
4559 Check_Nested_Access
(E
);
4562 Set_Entity_Or_Discriminal
(N
, E
);
4565 end Find_Direct_Name
;
4567 ------------------------
4568 -- Find_Expanded_Name --
4569 ------------------------
4571 -- This routine searches the homonym chain of the entity until it finds
4572 -- an entity declared in the scope denoted by the prefix. If the entity
4573 -- is private, it may nevertheless be immediately visible, if we are in
4574 -- the scope of its declaration.
4576 procedure Find_Expanded_Name
(N
: Node_Id
) is
4577 Selector
: constant Node_Id
:= Selector_Name
(N
);
4578 Candidate
: Entity_Id
:= Empty
;
4584 P_Name
:= Entity
(Prefix
(N
));
4587 -- If the prefix is a renamed package, look for the entity in the
4588 -- original package.
4590 if Ekind
(P_Name
) = E_Package
4591 and then Present
(Renamed_Object
(P_Name
))
4593 P_Name
:= Renamed_Object
(P_Name
);
4595 -- Rewrite node with entity field pointing to renamed object
4597 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
4598 Set_Entity
(Prefix
(N
), P_Name
);
4600 -- If the prefix is an object of a concurrent type, look for
4601 -- the entity in the associated task or protected type.
4603 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
4604 P_Name
:= Etype
(P_Name
);
4607 Id
:= Current_Entity
(Selector
);
4610 Is_New_Candidate
: Boolean;
4613 while Present
(Id
) loop
4614 if Scope
(Id
) = P_Name
then
4616 Is_New_Candidate
:= True;
4618 -- Ada 2005 (AI-217): Handle shadow entities associated with types
4619 -- declared in limited-withed nested packages. We don't need to
4620 -- handle E_Incomplete_Subtype entities because the entities in
4621 -- the limited view are always E_Incomplete_Type entities (see
4622 -- Build_Limited_Views). Regarding the expression used to evaluate
4623 -- the scope, it is important to note that the limited view also
4624 -- has shadow entities associated nested packages. For this reason
4625 -- the correct scope of the entity is the scope of the real entity
4626 -- The non-limited view may itself be incomplete, in which case
4627 -- get the full view if available.
4629 elsif From_With_Type
(Id
)
4630 and then Is_Type
(Id
)
4631 and then Ekind
(Id
) = E_Incomplete_Type
4632 and then Present
(Non_Limited_View
(Id
))
4633 and then Scope
(Non_Limited_View
(Id
)) = P_Name
4635 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
4636 Is_New_Candidate
:= True;
4639 Is_New_Candidate
:= False;
4642 if Is_New_Candidate
then
4643 if Is_Child_Unit
(Id
) then
4644 exit when Is_Visible_Child_Unit
(Id
)
4645 or else Is_Immediately_Visible
(Id
);
4648 exit when not Is_Hidden
(Id
)
4649 or else Is_Immediately_Visible
(Id
);
4658 and then (Ekind
(P_Name
) = E_Procedure
4660 Ekind
(P_Name
) = E_Function
)
4661 and then Is_Generic_Instance
(P_Name
)
4663 -- Expanded name denotes entity in (instance of) generic subprogram.
4664 -- The entity may be in the subprogram instance, or may denote one of
4665 -- the formals, which is declared in the enclosing wrapper package.
4667 P_Name
:= Scope
(P_Name
);
4669 Id
:= Current_Entity
(Selector
);
4670 while Present
(Id
) loop
4671 exit when Scope
(Id
) = P_Name
;
4676 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
4677 Set_Etype
(N
, Any_Type
);
4679 -- If we are looking for an entity defined in System, try to find it
4680 -- in the child package that may have been provided as an extension
4681 -- to System. The Extend_System pragma will have supplied the name of
4682 -- the extension, which may have to be loaded.
4684 if Chars
(P_Name
) = Name_System
4685 and then Scope
(P_Name
) = Standard_Standard
4686 and then Present
(System_Extend_Unit
)
4687 and then Present_System_Aux
(N
)
4689 Set_Entity
(Prefix
(N
), System_Aux_Id
);
4690 Find_Expanded_Name
(N
);
4693 elsif Nkind
(Selector
) = N_Operator_Symbol
4694 and then Has_Implicit_Operator
(N
)
4696 -- There is an implicit instance of the predefined operator in
4697 -- the given scope. The operator entity is defined in Standard.
4698 -- Has_Implicit_Operator makes the node into an Expanded_Name.
4702 elsif Nkind
(Selector
) = N_Character_Literal
4703 and then Has_Implicit_Character_Literal
(N
)
4705 -- If there is no literal defined in the scope denoted by the
4706 -- prefix, the literal may belong to (a type derived from)
4707 -- Standard_Character, for which we have no explicit literals.
4712 -- If the prefix is a single concurrent object, use its name in
4713 -- the error message, rather than that of the anonymous type.
4715 if Is_Concurrent_Type
(P_Name
)
4716 and then Is_Internal_Name
(Chars
(P_Name
))
4718 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
4720 Error_Msg_Node_2
:= P_Name
;
4723 if P_Name
= System_Aux_Id
then
4724 P_Name
:= Scope
(P_Name
);
4725 Set_Entity
(Prefix
(N
), P_Name
);
4728 if Present
(Candidate
) then
4730 -- If we know that the unit is a child unit we can give a more
4731 -- accurate error message.
4733 if Is_Child_Unit
(Candidate
) then
4735 -- If the candidate is a private child unit and we are in
4736 -- the visible part of a public unit, specialize the error
4737 -- message. There might be a private with_clause for it,
4738 -- but it is not currently active.
4740 if Is_Private_Descendant
(Candidate
)
4741 and then Ekind
(Current_Scope
) = E_Package
4742 and then not In_Private_Part
(Current_Scope
)
4743 and then not Is_Private_Descendant
(Current_Scope
)
4745 Error_Msg_N
("private child unit& is not visible here",
4748 -- Normal case where we have a missing with for a child unit
4751 Error_Msg_Qual_Level
:= 99;
4752 Error_Msg_NE
-- CODEFIX
4753 ("missing `WITH &;`", Selector
, Candidate
);
4754 Error_Msg_Qual_Level
:= 0;
4757 -- Here we don't know that this is a child unit
4760 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
4764 -- Within the instantiation of a child unit, the prefix may
4765 -- denote the parent instance, but the selector has the name
4766 -- of the original child. Find whether we are within the
4767 -- corresponding instance, and get the proper entity, which
4768 -- can only be an enclosing scope.
4771 and then In_Open_Scopes
(P_Name
)
4772 and then Is_Generic_Instance
(P_Name
)
4775 S
: Entity_Id
:= Current_Scope
;
4779 for J
in reverse 0 .. Scope_Stack
.Last
loop
4780 S
:= Scope_Stack
.Table
(J
).Entity
;
4782 exit when S
= Standard_Standard
;
4784 if Ekind_In
(S
, E_Function
,
4788 P
:= Generic_Parent
(Specification
4789 (Unit_Declaration_Node
(S
)));
4792 and then Chars
(Scope
(P
)) = Chars
(O_Name
)
4793 and then Chars
(P
) = Chars
(Selector
)
4804 -- If this is a selection from Ada, System or Interfaces, then
4805 -- we assume a missing with for the corresponding package.
4807 if Is_Known_Unit
(N
) then
4808 if not Error_Posted
(N
) then
4809 Error_Msg_Node_2
:= Selector
;
4810 Error_Msg_N
-- CODEFIX
4811 ("missing `WITH &.&;`", Prefix
(N
));
4814 -- If this is a selection from a dummy package, then suppress
4815 -- the error message, of course the entity is missing if the
4816 -- package is missing!
4818 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
4821 -- Here we have the case of an undefined component
4825 -- The prefix may hide a homonym in the context that
4826 -- declares the desired entity. This error can use a
4827 -- specialized message.
4829 if In_Open_Scopes
(P_Name
)
4830 and then Present
(Homonym
(P_Name
))
4831 and then Is_Compilation_Unit
(Homonym
(P_Name
))
4833 (Is_Immediately_Visible
(Homonym
(P_Name
))
4834 or else Is_Visible_Child_Unit
(Homonym
(P_Name
)))
4837 H
: constant Entity_Id
:= Homonym
(P_Name
);
4840 Id
:= First_Entity
(H
);
4841 while Present
(Id
) loop
4842 if Chars
(Id
) = Chars
(Selector
) then
4843 Error_Msg_Qual_Level
:= 99;
4844 Error_Msg_Name_1
:= Chars
(Selector
);
4846 ("% not declared in&", N
, P_Name
);
4848 ("\use fully qualified name starting with"
4849 & " Standard to make& visible", N
, H
);
4850 Error_Msg_Qual_Level
:= 0;
4857 -- If not found, standard error message.
4859 Error_Msg_NE
("& not declared in&", N
, Selector
);
4865 Error_Msg_NE
("& not declared in&", N
, Selector
);
4868 -- Check for misspelling of some entity in prefix
4870 Id
:= First_Entity
(P_Name
);
4871 while Present
(Id
) loop
4872 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
4873 and then not Is_Internal_Name
(Chars
(Id
))
4875 Error_Msg_NE
-- CODEFIX
4876 ("possible misspelling of&", Selector
, Id
);
4883 -- Specialize the message if this may be an instantiation
4884 -- of a child unit that was not mentioned in the context.
4886 if Nkind
(Parent
(N
)) = N_Package_Instantiation
4887 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
4888 and then Is_Compilation_Unit
4889 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
4891 Error_Msg_Node_2
:= Selector
;
4892 Error_Msg_N
-- CODEFIX
4893 ("\missing `WITH &.&;`", Prefix
(N
));
4903 if Comes_From_Source
(N
)
4904 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
4905 and then Present
(Equivalent_Type
(Id
))
4907 -- If we are not actually generating distribution code (i.e. the
4908 -- current PCS is the dummy non-distributed version), then the
4909 -- Equivalent_Type will be missing, and Id should be treated as
4910 -- a regular access-to-subprogram type.
4912 Id
:= Equivalent_Type
(Id
);
4913 Set_Chars
(Selector
, Chars
(Id
));
4916 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
4918 if Ekind
(P_Name
) = E_Package
4919 and then From_With_Type
(P_Name
)
4921 if From_With_Type
(Id
)
4922 or else Is_Type
(Id
)
4923 or else Ekind
(Id
) = E_Package
4928 ("limited withed package can only be used to access "
4929 & "incomplete types",
4934 if Is_Task_Type
(P_Name
)
4935 and then ((Ekind
(Id
) = E_Entry
4936 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
4938 (Ekind
(Id
) = E_Entry_Family
4940 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
4942 -- It is an entry call after all, either to the current task (which
4943 -- will deadlock) or to an enclosing task.
4945 Analyze_Selected_Component
(N
);
4949 Change_Selected_Component_To_Expanded_Name
(N
);
4951 -- Do style check and generate reference, but skip both steps if this
4952 -- entity has homonyms, since we may not have the right homonym set yet.
4953 -- The proper homonym will be set during the resolve phase.
4955 if Has_Homonym
(Id
) then
4958 Set_Entity_Or_Discriminal
(N
, Id
);
4959 Generate_Reference
(Id
, N
);
4962 if Is_Type
(Id
) then
4965 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
4968 -- Check for violation of No_Wide_Characters
4970 Check_Wide_Character_Restriction
(Id
, N
);
4972 -- If the Ekind of the entity is Void, it means that all homonyms are
4973 -- hidden from all visibility (RM 8.3(5,14-20)).
4975 if Ekind
(Id
) = E_Void
then
4976 Premature_Usage
(N
);
4978 elsif Is_Overloadable
(Id
)
4979 and then Present
(Homonym
(Id
))
4982 H
: Entity_Id
:= Homonym
(Id
);
4985 while Present
(H
) loop
4986 if Scope
(H
) = Scope
(Id
)
4989 or else Is_Immediately_Visible
(H
))
4991 Collect_Interps
(N
);
4998 -- If an extension of System is present, collect possible explicit
4999 -- overloadings declared in the extension.
5001 if Chars
(P_Name
) = Name_System
5002 and then Scope
(P_Name
) = Standard_Standard
5003 and then Present
(System_Extend_Unit
)
5004 and then Present_System_Aux
(N
)
5006 H
:= Current_Entity
(Id
);
5008 while Present
(H
) loop
5009 if Scope
(H
) = System_Aux_Id
then
5010 Add_One_Interp
(N
, H
, Etype
(H
));
5019 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
5020 and then Scope
(Id
) /= Standard_Standard
5022 -- In addition to user-defined operators in the given scope, there
5023 -- may be an implicit instance of the predefined operator. The
5024 -- operator (defined in Standard) is found in Has_Implicit_Operator,
5025 -- and added to the interpretations. Procedure Add_One_Interp will
5026 -- determine which hides which.
5028 if Has_Implicit_Operator
(N
) then
5032 end Find_Expanded_Name
;
5034 -------------------------
5035 -- Find_Renamed_Entity --
5036 -------------------------
5038 function Find_Renamed_Entity
5042 Is_Actual
: Boolean := False) return Entity_Id
5045 I1
: Interp_Index
:= 0; -- Suppress junk warnings
5051 function Enclosing_Instance
return Entity_Id
;
5052 -- If the renaming determines the entity for the default of a formal
5053 -- subprogram nested within another instance, choose the innermost
5054 -- candidate. This is because if the formal has a box, and we are within
5055 -- an enclosing instance where some candidate interpretations are local
5056 -- to this enclosing instance, we know that the default was properly
5057 -- resolved when analyzing the generic, so we prefer the local
5058 -- candidates to those that are external. This is not always the case
5059 -- but is a reasonable heuristic on the use of nested generics. The
5060 -- proper solution requires a full renaming model.
5062 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
5063 -- If the renamed entity is an implicit operator, check whether it is
5064 -- visible because its operand type is properly visible. This check
5065 -- applies to explicit renamed entities that appear in the source in a
5066 -- renaming declaration or a formal subprogram instance, but not to
5067 -- default generic actuals with a name.
5069 function Report_Overload
return Entity_Id
;
5070 -- List possible interpretations, and specialize message in the
5071 -- case of a generic actual.
5073 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
5074 -- Determine whether a candidate subprogram is defined within the
5075 -- enclosing instance. If yes, it has precedence over outer candidates.
5077 ------------------------
5078 -- Enclosing_Instance --
5079 ------------------------
5081 function Enclosing_Instance
return Entity_Id
is
5085 if not Is_Generic_Instance
(Current_Scope
)
5086 and then not Is_Actual
5091 S
:= Scope
(Current_Scope
);
5092 while S
/= Standard_Standard
loop
5093 if Is_Generic_Instance
(S
) then
5101 end Enclosing_Instance
;
5103 --------------------------
5104 -- Is_Visible_Operation --
5105 --------------------------
5107 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
5113 if Ekind
(Op
) /= E_Operator
5114 or else Scope
(Op
) /= Standard_Standard
5115 or else (In_Instance
5118 or else Present
(Enclosing_Instance
)))
5123 -- For a fixed point type operator, check the resulting type,
5124 -- because it may be a mixed mode integer * fixed operation.
5126 if Present
(Next_Formal
(First_Formal
(New_S
)))
5127 and then Is_Fixed_Point_Type
(Etype
(New_S
))
5129 Typ
:= Etype
(New_S
);
5131 Typ
:= Etype
(First_Formal
(New_S
));
5134 Btyp
:= Base_Type
(Typ
);
5136 if Nkind
(Nam
) /= N_Expanded_Name
then
5137 return (In_Open_Scopes
(Scope
(Btyp
))
5138 or else Is_Potentially_Use_Visible
(Btyp
)
5139 or else In_Use
(Btyp
)
5140 or else In_Use
(Scope
(Btyp
)));
5143 Scop
:= Entity
(Prefix
(Nam
));
5145 if Ekind
(Scop
) = E_Package
5146 and then Present
(Renamed_Object
(Scop
))
5148 Scop
:= Renamed_Object
(Scop
);
5151 -- Operator is visible if prefix of expanded name denotes
5152 -- scope of type, or else type is defined in System_Aux
5153 -- and the prefix denotes System.
5155 return Scope
(Btyp
) = Scop
5156 or else (Scope
(Btyp
) = System_Aux_Id
5157 and then Scope
(Scope
(Btyp
)) = Scop
);
5160 end Is_Visible_Operation
;
5166 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
5170 Sc
:= Scope
(Inner
);
5171 while Sc
/= Standard_Standard
loop
5182 ---------------------
5183 -- Report_Overload --
5184 ---------------------
5186 function Report_Overload
return Entity_Id
is
5189 Error_Msg_NE
-- CODEFIX
5190 ("ambiguous actual subprogram&, " &
5191 "possible interpretations:", N
, Nam
);
5193 Error_Msg_N
-- CODEFIX
5194 ("ambiguous subprogram, " &
5195 "possible interpretations:", N
);
5198 List_Interps
(Nam
, N
);
5200 end Report_Overload
;
5202 -- Start of processing for Find_Renamed_Entry
5206 Candidate_Renaming
:= Empty
;
5208 if not Is_Overloaded
(Nam
) then
5209 if Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
5210 Candidate_Renaming
:= New_S
;
5212 if Is_Visible_Operation
(Entity
(Nam
)) then
5213 Old_S
:= Entity
(Nam
);
5217 Present
(First_Formal
(Entity
(Nam
)))
5218 and then Present
(First_Formal
(New_S
))
5219 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
))))
5220 = Base_Type
(Etype
(First_Formal
(New_S
))))
5222 Candidate_Renaming
:= Entity
(Nam
);
5226 Get_First_Interp
(Nam
, Ind
, It
);
5227 while Present
(It
.Nam
) loop
5228 if Entity_Matches_Spec
(It
.Nam
, New_S
)
5229 and then Is_Visible_Operation
(It
.Nam
)
5231 if Old_S
/= Any_Id
then
5233 -- Note: The call to Disambiguate only happens if a
5234 -- previous interpretation was found, in which case I1
5235 -- has received a value.
5237 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
5239 if It1
= No_Interp
then
5240 Inst
:= Enclosing_Instance
;
5242 if Present
(Inst
) then
5243 if Within
(It
.Nam
, Inst
) then
5245 elsif Within
(Old_S
, Inst
) then
5248 return Report_Overload
;
5252 return Report_Overload
;
5266 Present
(First_Formal
(It
.Nam
))
5267 and then Present
(First_Formal
(New_S
))
5268 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
)))
5269 = Base_Type
(Etype
(First_Formal
(New_S
))))
5271 Candidate_Renaming
:= It
.Nam
;
5274 Get_Next_Interp
(Ind
, It
);
5277 Set_Entity
(Nam
, Old_S
);
5278 Set_Is_Overloaded
(Nam
, False);
5282 end Find_Renamed_Entity
;
5284 -----------------------------
5285 -- Find_Selected_Component --
5286 -----------------------------
5288 procedure Find_Selected_Component
(N
: Node_Id
) is
5289 P
: constant Node_Id
:= Prefix
(N
);
5292 -- Entity denoted by prefix
5302 if Nkind
(P
) = N_Error
then
5305 -- If the selector already has an entity, the node has been constructed
5306 -- in the course of expansion, and is known to be valid. Do not verify
5307 -- that it is defined for the type (it may be a private component used
5308 -- in the expansion of record equality).
5310 elsif Present
(Entity
(Selector_Name
(N
))) then
5312 or else Etype
(N
) = Any_Type
5315 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
5316 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
5320 Set_Etype
(Sel_Name
, Etype
(Selector
));
5322 if not Is_Entity_Name
(P
) then
5326 -- Build an actual subtype except for the first parameter
5327 -- of an init proc, where this actual subtype is by
5328 -- definition incorrect, since the object is uninitialized
5329 -- (and does not even have defined discriminants etc.)
5331 if Is_Entity_Name
(P
)
5332 and then Ekind
(Entity
(P
)) = E_Function
5334 Nam
:= New_Copy
(P
);
5336 if Is_Overloaded
(P
) then
5337 Save_Interps
(P
, Nam
);
5341 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
5343 Analyze_Selected_Component
(N
);
5346 elsif Ekind
(Selector
) = E_Component
5347 and then (not Is_Entity_Name
(P
)
5348 or else Chars
(Entity
(P
)) /= Name_uInit
)
5351 Build_Actual_Subtype_Of_Component
(
5352 Etype
(Selector
), N
);
5357 if No
(C_Etype
) then
5358 C_Etype
:= Etype
(Selector
);
5360 Insert_Action
(N
, C_Etype
);
5361 C_Etype
:= Defining_Identifier
(C_Etype
);
5364 Set_Etype
(N
, C_Etype
);
5367 -- If this is the name of an entry or protected operation, and
5368 -- the prefix is an access type, insert an explicit dereference,
5369 -- so that entry calls are treated uniformly.
5371 if Is_Access_Type
(Etype
(P
))
5372 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
5375 New_P
: constant Node_Id
:=
5376 Make_Explicit_Dereference
(Sloc
(P
),
5377 Prefix
=> Relocate_Node
(P
));
5380 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
5384 -- If the selected component appears within a default expression
5385 -- and it has an actual subtype, the pre-analysis has not yet
5386 -- completed its analysis, because Insert_Actions is disabled in
5387 -- that context. Within the init proc of the enclosing type we
5388 -- must complete this analysis, if an actual subtype was created.
5390 elsif Inside_Init_Proc
then
5392 Typ
: constant Entity_Id
:= Etype
(N
);
5393 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
5395 if Nkind
(Decl
) = N_Subtype_Declaration
5396 and then not Analyzed
(Decl
)
5397 and then Is_List_Member
(Decl
)
5398 and then No
(Parent
(Decl
))
5401 Insert_Action
(N
, Decl
);
5408 elsif Is_Entity_Name
(P
) then
5409 P_Name
:= Entity
(P
);
5411 -- The prefix may denote an enclosing type which is the completion
5412 -- of an incomplete type declaration.
5414 if Is_Type
(P_Name
) then
5415 Set_Entity
(P
, Get_Full_View
(P_Name
));
5416 Set_Etype
(P
, Entity
(P
));
5417 P_Name
:= Entity
(P
);
5420 P_Type
:= Base_Type
(Etype
(P
));
5422 if Debug_Flag_E
then
5423 Write_Str
("Found prefix type to be ");
5424 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
5427 -- First check for components of a record object (not the
5428 -- result of a call, which is handled below).
5430 if Is_Appropriate_For_Record
(P_Type
)
5431 and then not Is_Overloadable
(P_Name
)
5432 and then not Is_Type
(P_Name
)
5434 -- Selected component of record. Type checking will validate
5435 -- name of selector.
5436 -- ??? could we rewrite an implicit dereference into an explicit
5439 Analyze_Selected_Component
(N
);
5441 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
5442 and then not In_Open_Scopes
(P_Name
)
5443 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
5444 or else not In_Open_Scopes
(Etype
(P_Name
)))
5446 -- Call to protected operation or entry. Type checking is
5447 -- needed on the prefix.
5449 Analyze_Selected_Component
(N
);
5451 elsif (In_Open_Scopes
(P_Name
)
5452 and then Ekind
(P_Name
) /= E_Void
5453 and then not Is_Overloadable
(P_Name
))
5454 or else (Is_Concurrent_Type
(Etype
(P_Name
))
5455 and then In_Open_Scopes
(Etype
(P_Name
)))
5457 -- Prefix denotes an enclosing loop, block, or task, i.e. an
5458 -- enclosing construct that is not a subprogram or accept.
5460 Find_Expanded_Name
(N
);
5462 elsif Ekind
(P_Name
) = E_Package
then
5463 Find_Expanded_Name
(N
);
5465 elsif Is_Overloadable
(P_Name
) then
5467 -- The subprogram may be a renaming (of an enclosing scope) as
5468 -- in the case of the name of the generic within an instantiation.
5470 if (Ekind
(P_Name
) = E_Procedure
5471 or else Ekind
(P_Name
) = E_Function
)
5472 and then Present
(Alias
(P_Name
))
5473 and then Is_Generic_Instance
(Alias
(P_Name
))
5475 P_Name
:= Alias
(P_Name
);
5478 if Is_Overloaded
(P
) then
5480 -- The prefix must resolve to a unique enclosing construct
5483 Found
: Boolean := False;
5488 Get_First_Interp
(P
, Ind
, It
);
5489 while Present
(It
.Nam
) loop
5490 if In_Open_Scopes
(It
.Nam
) then
5493 "prefix must be unique enclosing scope", N
);
5494 Set_Entity
(N
, Any_Id
);
5495 Set_Etype
(N
, Any_Type
);
5504 Get_Next_Interp
(Ind
, It
);
5509 if In_Open_Scopes
(P_Name
) then
5510 Set_Entity
(P
, P_Name
);
5511 Set_Is_Overloaded
(P
, False);
5512 Find_Expanded_Name
(N
);
5515 -- If no interpretation as an expanded name is possible, it
5516 -- must be a selected component of a record returned by a
5517 -- function call. Reformat prefix as a function call, the rest
5518 -- is done by type resolution. If the prefix is procedure or
5519 -- entry, as is P.X; this is an error.
5521 if Ekind
(P_Name
) /= E_Function
5522 and then (not Is_Overloaded
(P
)
5524 Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
5526 -- Prefix may mention a package that is hidden by a local
5527 -- declaration: let the user know. Scan the full homonym
5528 -- chain, the candidate package may be anywhere on it.
5530 if Present
(Homonym
(Current_Entity
(P_Name
))) then
5532 P_Name
:= Current_Entity
(P_Name
);
5534 while Present
(P_Name
) loop
5535 exit when Ekind
(P_Name
) = E_Package
;
5536 P_Name
:= Homonym
(P_Name
);
5539 if Present
(P_Name
) then
5540 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
5543 ("package& is hidden by declaration#",
5546 Set_Entity
(Prefix
(N
), P_Name
);
5547 Find_Expanded_Name
(N
);
5550 P_Name
:= Entity
(Prefix
(N
));
5555 ("invalid prefix in selected component&", N
, P_Name
);
5556 Change_Selected_Component_To_Expanded_Name
(N
);
5557 Set_Entity
(N
, Any_Id
);
5558 Set_Etype
(N
, Any_Type
);
5561 Nam
:= New_Copy
(P
);
5562 Save_Interps
(P
, Nam
);
5564 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
5566 Analyze_Selected_Component
(N
);
5570 -- Remaining cases generate various error messages
5573 -- Format node as expanded name, to avoid cascaded errors
5575 Change_Selected_Component_To_Expanded_Name
(N
);
5576 Set_Entity
(N
, Any_Id
);
5577 Set_Etype
(N
, Any_Type
);
5579 -- Issue error message, but avoid this if error issued already.
5580 -- Use identifier of prefix if one is available.
5582 if P_Name
= Any_Id
then
5585 elsif Ekind
(P_Name
) = E_Void
then
5586 Premature_Usage
(P
);
5588 elsif Nkind
(P
) /= N_Attribute_Reference
then
5590 "invalid prefix in selected component&", P
);
5592 if Is_Access_Type
(P_Type
)
5593 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
5596 ("\dereference must not be of an incomplete type " &
5602 "invalid prefix in selected component", P
);
5607 -- If prefix is not the name of an entity, it must be an expression,
5608 -- whose type is appropriate for a record. This is determined by
5611 Analyze_Selected_Component
(N
);
5613 end Find_Selected_Component
;
5619 procedure Find_Type
(N
: Node_Id
) is
5629 elsif Nkind
(N
) = N_Attribute_Reference
then
5631 -- Class attribute. This is not valid in Ada 83 mode, but we do not
5632 -- need to enforce that at this point, since the declaration of the
5633 -- tagged type in the prefix would have been flagged already.
5635 if Attribute_Name
(N
) = Name_Class
then
5636 Check_Restriction
(No_Dispatch
, N
);
5637 Find_Type
(Prefix
(N
));
5639 -- Propagate error from bad prefix
5641 if Etype
(Prefix
(N
)) = Any_Type
then
5642 Set_Entity
(N
, Any_Type
);
5643 Set_Etype
(N
, Any_Type
);
5647 T
:= Base_Type
(Entity
(Prefix
(N
)));
5649 -- Case where type is not known to be tagged. Its appearance in
5650 -- the prefix of the 'Class attribute indicates that the full view
5653 if not Is_Tagged_Type
(T
) then
5654 if Ekind
(T
) = E_Incomplete_Type
then
5656 -- It is legal to denote the class type of an incomplete
5657 -- type. The full type will have to be tagged, of course.
5658 -- In Ada 2005 this usage is declared obsolescent, so we
5659 -- warn accordingly. This usage is only legal if the type
5660 -- is completed in the current scope, and not for a limited
5663 if not Is_Tagged_Type
(T
)
5664 and then Ada_Version
>= Ada_05
5666 if From_With_Type
(T
) then
5668 ("prefix of Class attribute must be tagged", N
);
5669 Set_Etype
(N
, Any_Type
);
5670 Set_Entity
(N
, Any_Type
);
5673 -- ??? This test is temporarily disabled (always False)
5674 -- because it causes an unwanted warning on GNAT sources
5675 -- (built with -gnatg, which includes Warn_On_Obsolescent_
5676 -- Feature). Once this issue is cleared in the sources, it
5679 elsif Warn_On_Obsolescent_Feature
5683 ("applying 'Class to an untagged incomplete type"
5684 & " is an obsolescent feature (RM J.11)", N
);
5688 Set_Is_Tagged_Type
(T
);
5689 Set_Primitive_Operations
(T
, New_Elmt_List
);
5690 Make_Class_Wide_Type
(T
);
5691 Set_Entity
(N
, Class_Wide_Type
(T
));
5692 Set_Etype
(N
, Class_Wide_Type
(T
));
5694 elsif Ekind
(T
) = E_Private_Type
5695 and then not Is_Generic_Type
(T
)
5696 and then In_Private_Part
(Scope
(T
))
5698 -- The Class attribute can be applied to an untagged private
5699 -- type fulfilled by a tagged type prior to the full type
5700 -- declaration (but only within the parent package's private
5701 -- part). Create the class-wide type now and check that the
5702 -- full type is tagged later during its analysis. Note that
5703 -- we do not mark the private type as tagged, unlike the
5704 -- case of incomplete types, because the type must still
5705 -- appear untagged to outside units.
5707 if No
(Class_Wide_Type
(T
)) then
5708 Make_Class_Wide_Type
(T
);
5711 Set_Entity
(N
, Class_Wide_Type
(T
));
5712 Set_Etype
(N
, Class_Wide_Type
(T
));
5715 -- Should we introduce a type Any_Tagged and use Wrong_Type
5716 -- here, it would be a bit more consistent???
5719 ("tagged type required, found}",
5720 Prefix
(N
), First_Subtype
(T
));
5721 Set_Entity
(N
, Any_Type
);
5725 -- Case of tagged type
5728 if Is_Concurrent_Type
(T
) then
5729 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
5731 -- Previous error. Use current type, which at least
5732 -- provides some operations.
5734 C
:= Entity
(Prefix
(N
));
5737 C
:= Class_Wide_Type
5738 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
5742 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
5745 Set_Entity_With_Style_Check
(N
, C
);
5746 Generate_Reference
(C
, N
);
5750 -- Base attribute, not allowed in Ada 83
5752 elsif Attribute_Name
(N
) = Name_Base
then
5753 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
5755 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
5758 Find_Type
(Prefix
(N
));
5759 Typ
:= Entity
(Prefix
(N
));
5761 if Ada_Version
>= Ada_95
5762 and then not Is_Scalar_Type
(Typ
)
5763 and then not Is_Generic_Type
(Typ
)
5766 ("prefix of Base attribute must be scalar type",
5769 elsif Warn_On_Redundant_Constructs
5770 and then Base_Type
(Typ
) = Typ
5772 Error_Msg_NE
-- CODEFIX
5773 ("?redundant attribute, & is its own base type", N
, Typ
);
5776 T
:= Base_Type
(Typ
);
5778 -- Rewrite attribute reference with type itself (see similar
5779 -- processing in Analyze_Attribute, case Base). Preserve prefix
5780 -- if present, for other legality checks.
5782 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
5784 Make_Expanded_Name
(Sloc
(N
),
5786 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
5787 Selector_Name
=> New_Reference_To
(T
, Sloc
(N
))));
5790 Rewrite
(N
, New_Reference_To
(T
, Sloc
(N
)));
5797 elsif Attribute_Name
(N
) = Name_Stub_Type
then
5799 -- This is handled in Analyze_Attribute
5803 -- All other attributes are invalid in a subtype mark
5806 Error_Msg_N
("invalid attribute in subtype mark", N
);
5812 if Is_Entity_Name
(N
) then
5813 T_Name
:= Entity
(N
);
5815 Error_Msg_N
("subtype mark required in this context", N
);
5816 Set_Etype
(N
, Any_Type
);
5820 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
5822 -- Undefined id. Make it into a valid type
5824 Set_Entity
(N
, Any_Type
);
5826 elsif not Is_Type
(T_Name
)
5827 and then T_Name
/= Standard_Void_Type
5829 Error_Msg_Sloc
:= Sloc
(T_Name
);
5830 Error_Msg_N
("subtype mark required in this context", N
);
5831 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
5832 Set_Entity
(N
, Any_Type
);
5835 -- If the type is an incomplete type created to handle
5836 -- anonymous access components of a record type, then the
5837 -- incomplete type is the visible entity and subsequent
5838 -- references will point to it. Mark the original full
5839 -- type as referenced, to prevent spurious warnings.
5841 if Is_Incomplete_Type
(T_Name
)
5842 and then Present
(Full_View
(T_Name
))
5843 and then not Comes_From_Source
(T_Name
)
5845 Set_Referenced
(Full_View
(T_Name
));
5848 T_Name
:= Get_Full_View
(T_Name
);
5850 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
5851 -- limited-with clauses
5853 if From_With_Type
(T_Name
)
5854 and then Ekind
(T_Name
) in Incomplete_Kind
5855 and then Present
(Non_Limited_View
(T_Name
))
5856 and then Is_Interface
(Non_Limited_View
(T_Name
))
5858 T_Name
:= Non_Limited_View
(T_Name
);
5861 if In_Open_Scopes
(T_Name
) then
5862 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
5864 -- In Ada 2005, a task name can be used in an access
5865 -- definition within its own body. It cannot be used
5866 -- in the discriminant part of the task declaration,
5867 -- nor anywhere else in the declaration because entries
5868 -- cannot have access parameters.
5870 if Ada_Version
>= Ada_05
5871 and then Nkind
(Parent
(N
)) = N_Access_Definition
5873 Set_Entity
(N
, T_Name
);
5874 Set_Etype
(N
, T_Name
);
5876 if Has_Completion
(T_Name
) then
5881 ("task type cannot be used as type mark " &
5882 "within its own declaration", N
);
5887 ("task type cannot be used as type mark " &
5888 "within its own spec or body", N
);
5891 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
5893 -- In Ada 2005, a protected name can be used in an access
5894 -- definition within its own body.
5896 if Ada_Version
>= Ada_05
5897 and then Nkind
(Parent
(N
)) = N_Access_Definition
5899 Set_Entity
(N
, T_Name
);
5900 Set_Etype
(N
, T_Name
);
5905 ("protected type cannot be used as type mark " &
5906 "within its own spec or body", N
);
5910 Error_Msg_N
("type declaration cannot refer to itself", N
);
5913 Set_Etype
(N
, Any_Type
);
5914 Set_Entity
(N
, Any_Type
);
5915 Set_Error_Posted
(T_Name
);
5919 Set_Entity
(N
, T_Name
);
5920 Set_Etype
(N
, T_Name
);
5924 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
5925 if Is_Fixed_Point_Type
(Etype
(N
)) then
5926 Check_Restriction
(No_Fixed_Point
, N
);
5927 elsif Is_Floating_Point_Type
(Etype
(N
)) then
5928 Check_Restriction
(No_Floating_Point
, N
);
5933 ------------------------------------
5934 -- Has_Implicit_Character_Literal --
5935 ------------------------------------
5937 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
5939 Found
: Boolean := False;
5940 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
5941 Priv_Id
: Entity_Id
:= Empty
;
5944 if Ekind
(P
) = E_Package
5945 and then not In_Open_Scopes
(P
)
5947 Priv_Id
:= First_Private_Entity
(P
);
5950 if P
= Standard_Standard
then
5951 Change_Selected_Component_To_Expanded_Name
(N
);
5952 Rewrite
(N
, Selector_Name
(N
));
5954 Set_Etype
(Original_Node
(N
), Standard_Character
);
5958 Id
:= First_Entity
(P
);
5960 and then Id
/= Priv_Id
5962 if Is_Standard_Character_Type
(Id
)
5963 and then Id
= Base_Type
(Id
)
5965 -- We replace the node with the literal itself, resolve as a
5966 -- character, and set the type correctly.
5969 Change_Selected_Component_To_Expanded_Name
(N
);
5970 Rewrite
(N
, Selector_Name
(N
));
5973 Set_Etype
(Original_Node
(N
), Id
);
5977 -- More than one type derived from Character in given scope.
5978 -- Collect all possible interpretations.
5980 Add_One_Interp
(N
, Id
, Id
);
5988 end Has_Implicit_Character_Literal
;
5990 ----------------------
5991 -- Has_Private_With --
5992 ----------------------
5994 function Has_Private_With
(E
: Entity_Id
) return Boolean is
5995 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
5999 Item
:= First
(Context_Items
(Comp_Unit
));
6000 while Present
(Item
) loop
6001 if Nkind
(Item
) = N_With_Clause
6002 and then Private_Present
(Item
)
6003 and then Entity
(Name
(Item
)) = E
6012 end Has_Private_With
;
6014 ---------------------------
6015 -- Has_Implicit_Operator --
6016 ---------------------------
6018 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
6019 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
6020 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
6022 Priv_Id
: Entity_Id
:= Empty
;
6024 procedure Add_Implicit_Operator
6026 Op_Type
: Entity_Id
:= Empty
);
6027 -- Add implicit interpretation to node N, using the type for which a
6028 -- predefined operator exists. If the operator yields a boolean type,
6029 -- the Operand_Type is implicitly referenced by the operator, and a
6030 -- reference to it must be generated.
6032 ---------------------------
6033 -- Add_Implicit_Operator --
6034 ---------------------------
6036 procedure Add_Implicit_Operator
6038 Op_Type
: Entity_Id
:= Empty
)
6040 Predef_Op
: Entity_Id
;
6043 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
6045 while Present
(Predef_Op
)
6046 and then Scope
(Predef_Op
) /= Standard_Standard
6048 Predef_Op
:= Homonym
(Predef_Op
);
6051 if Nkind
(N
) = N_Selected_Component
then
6052 Change_Selected_Component_To_Expanded_Name
(N
);
6055 -- If the context is an unanalyzed function call, determine whether
6056 -- a binary or unary interpretation is required.
6058 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
6060 Is_Binary_Call
: constant Boolean :=
6062 (Next
(First
(Expressions
(Parent
(N
)))));
6063 Is_Binary_Op
: constant Boolean :=
6065 (Predef_Op
) /= Last_Entity
(Predef_Op
);
6066 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
6069 if Is_Binary_Call
then
6070 if Is_Binary_Op
then
6071 Add_One_Interp
(N
, Predef_Op
, T
);
6073 Add_One_Interp
(N
, Predef_Op2
, T
);
6077 if not Is_Binary_Op
then
6078 Add_One_Interp
(N
, Predef_Op
, T
);
6080 Add_One_Interp
(N
, Predef_Op2
, T
);
6086 Add_One_Interp
(N
, Predef_Op
, T
);
6088 -- For operators with unary and binary interpretations, if
6089 -- context is not a call, add both
6091 if Present
(Homonym
(Predef_Op
)) then
6092 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
6096 -- The node is a reference to a predefined operator, and
6097 -- an implicit reference to the type of its operands.
6099 if Present
(Op_Type
) then
6100 Generate_Operator_Reference
(N
, Op_Type
);
6102 Generate_Operator_Reference
(N
, T
);
6104 end Add_Implicit_Operator
;
6106 -- Start of processing for Has_Implicit_Operator
6109 if Ekind
(P
) = E_Package
6110 and then not In_Open_Scopes
(P
)
6112 Priv_Id
:= First_Private_Entity
(P
);
6115 Id
:= First_Entity
(P
);
6119 -- Boolean operators: an implicit declaration exists if the scope
6120 -- contains a declaration for a derived Boolean type, or for an
6121 -- array of Boolean type.
6123 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
6124 while Id
/= Priv_Id
loop
6125 if Valid_Boolean_Arg
(Id
)
6126 and then Id
= Base_Type
(Id
)
6128 Add_Implicit_Operator
(Id
);
6135 -- Equality: look for any non-limited type (result is Boolean)
6137 when Name_Op_Eq | Name_Op_Ne
=>
6138 while Id
/= Priv_Id
loop
6140 and then not Is_Limited_Type
(Id
)
6141 and then Id
= Base_Type
(Id
)
6143 Add_Implicit_Operator
(Standard_Boolean
, Id
);
6150 -- Comparison operators: scalar type, or array of scalar
6152 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
6153 while Id
/= Priv_Id
loop
6154 if (Is_Scalar_Type
(Id
)
6155 or else (Is_Array_Type
(Id
)
6156 and then Is_Scalar_Type
(Component_Type
(Id
))))
6157 and then Id
= Base_Type
(Id
)
6159 Add_Implicit_Operator
(Standard_Boolean
, Id
);
6166 -- Arithmetic operators: any numeric type
6176 while Id
/= Priv_Id
loop
6177 if Is_Numeric_Type
(Id
)
6178 and then Id
= Base_Type
(Id
)
6180 Add_Implicit_Operator
(Id
);
6187 -- Concatenation: any one-dimensional array type
6189 when Name_Op_Concat
=>
6190 while Id
/= Priv_Id
loop
6191 if Is_Array_Type
(Id
) and then Number_Dimensions
(Id
) = 1
6192 and then Id
= Base_Type
(Id
)
6194 Add_Implicit_Operator
(Id
);
6201 -- What is the others condition here? Should we be using a
6202 -- subtype of Name_Id that would restrict to operators ???
6204 when others => null;
6207 -- If we fall through, then we do not have an implicit operator
6211 end Has_Implicit_Operator
;
6213 --------------------
6214 -- In_Open_Scopes --
6215 --------------------
6217 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
6219 -- Several scope stacks are maintained by Scope_Stack. The base of the
6220 -- currently active scope stack is denoted by the Is_Active_Stack_Base
6221 -- flag in the scope stack entry. Note that the scope stacks used to
6222 -- simply be delimited implicitly by the presence of Standard_Standard
6223 -- at their base, but there now are cases where this is not sufficient
6224 -- because Standard_Standard actually may appear in the middle of the
6225 -- active set of scopes.
6227 for J
in reverse 0 .. Scope_Stack
.Last
loop
6228 if Scope_Stack
.Table
(J
).Entity
= S
then
6232 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
6233 -- cases where Standard_Standard appears in the middle of the active
6234 -- set of scopes. This affects the declaration and overriding of
6235 -- private inherited operations in instantiations of generic child
6238 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
6244 -----------------------------
6245 -- Inherit_Renamed_Profile --
6246 -----------------------------
6248 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
6255 if Ekind
(Old_S
) = E_Operator
then
6256 New_F
:= First_Formal
(New_S
);
6258 while Present
(New_F
) loop
6259 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
6260 Next_Formal
(New_F
);
6263 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
6266 New_F
:= First_Formal
(New_S
);
6267 Old_F
:= First_Formal
(Old_S
);
6269 while Present
(New_F
) loop
6270 New_T
:= Etype
(New_F
);
6271 Old_T
:= Etype
(Old_F
);
6273 -- If the new type is a renaming of the old one, as is the
6274 -- case for actuals in instances, retain its name, to simplify
6275 -- later disambiguation.
6277 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
6278 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
6279 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
6283 Set_Etype
(New_F
, Old_T
);
6286 Next_Formal
(New_F
);
6287 Next_Formal
(Old_F
);
6290 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
6291 Set_Etype
(New_S
, Etype
(Old_S
));
6294 end Inherit_Renamed_Profile
;
6300 procedure Initialize
is
6305 -------------------------
6306 -- Install_Use_Clauses --
6307 -------------------------
6309 procedure Install_Use_Clauses
6311 Force_Installation
: Boolean := False)
6319 while Present
(U
) loop
6321 -- Case of USE package
6323 if Nkind
(U
) = N_Use_Package_Clause
then
6324 P
:= First
(Names
(U
));
6325 while Present
(P
) loop
6328 if Ekind
(Id
) = E_Package
then
6330 Note_Redundant_Use
(P
);
6332 elsif Present
(Renamed_Object
(Id
))
6333 and then In_Use
(Renamed_Object
(Id
))
6335 Note_Redundant_Use
(P
);
6337 elsif Force_Installation
or else Applicable_Use
(P
) then
6338 Use_One_Package
(Id
, U
);
6349 P
:= First
(Subtype_Marks
(U
));
6350 while Present
(P
) loop
6351 if not Is_Entity_Name
(P
)
6352 or else No
(Entity
(P
))
6356 elsif Entity
(P
) /= Any_Type
then
6364 Next_Use_Clause
(U
);
6366 end Install_Use_Clauses
;
6368 -------------------------------------
6369 -- Is_Appropriate_For_Entry_Prefix --
6370 -------------------------------------
6372 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
6373 P_Type
: Entity_Id
:= T
;
6376 if Is_Access_Type
(P_Type
) then
6377 P_Type
:= Designated_Type
(P_Type
);
6380 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
6381 end Is_Appropriate_For_Entry_Prefix
;
6383 -------------------------------
6384 -- Is_Appropriate_For_Record --
6385 -------------------------------
6387 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
6389 function Has_Components
(T1
: Entity_Id
) return Boolean;
6390 -- Determine if given type has components (i.e. is either a record
6391 -- type or a type that has discriminants).
6393 --------------------
6394 -- Has_Components --
6395 --------------------
6397 function Has_Components
(T1
: Entity_Id
) return Boolean is
6399 return Is_Record_Type
(T1
)
6400 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
6401 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
6402 or else (Is_Incomplete_Type
(T1
)
6403 and then From_With_Type
(T1
)
6404 and then Present
(Non_Limited_View
(T1
))
6405 and then Is_Record_Type
6406 (Get_Full_View
(Non_Limited_View
(T1
))));
6409 -- Start of processing for Is_Appropriate_For_Record
6414 and then (Has_Components
(T
)
6415 or else (Is_Access_Type
(T
)
6416 and then Has_Components
(Designated_Type
(T
))));
6417 end Is_Appropriate_For_Record
;
6419 ------------------------
6420 -- Note_Redundant_Use --
6421 ------------------------
6423 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
6424 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
6425 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
6426 Decl
: constant Node_Id
:= Parent
(Clause
);
6428 Prev_Use
: Node_Id
:= Empty
;
6429 Redundant
: Node_Id
:= Empty
;
6430 -- The Use_Clause which is actually redundant. In the simplest case it
6431 -- is Pack itself, but when we compile a body we install its context
6432 -- before that of its spec, in which case it is the use_clause in the
6433 -- spec that will appear to be redundant, and we want the warning to be
6434 -- placed on the body. Similar complications appear when the redundancy
6435 -- is between a child unit and one of its ancestors.
6438 Set_Redundant_Use
(Clause
, True);
6440 if not Comes_From_Source
(Clause
)
6442 or else not Warn_On_Redundant_Constructs
6447 if not Is_Compilation_Unit
(Current_Scope
) then
6449 -- If the use_clause is in an inner scope, it is made redundant by
6450 -- some clause in the current context, with one exception: If we're
6451 -- compiling a nested package body, and the use_clause comes from the
6452 -- corresponding spec, the clause is not necessarily fully redundant,
6453 -- so we should not warn. If a warning was warranted, it would have
6454 -- been given when the spec was processed.
6456 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
6458 Package_Spec_Entity
: constant Entity_Id
:=
6459 Defining_Unit_Name
(Parent
(Decl
));
6461 if In_Package_Body
(Package_Spec_Entity
) then
6467 Redundant
:= Clause
;
6468 Prev_Use
:= Cur_Use
;
6470 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
6472 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
6473 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
6477 if Cur_Unit
= New_Unit
then
6479 -- Redundant clause in same body
6481 Redundant
:= Clause
;
6482 Prev_Use
:= Cur_Use
;
6484 elsif Cur_Unit
= Current_Sem_Unit
then
6486 -- If the new clause is not in the current unit it has been
6487 -- analyzed first, and it makes the other one redundant.
6488 -- However, if the new clause appears in a subunit, Cur_Unit
6489 -- is still the parent, and in that case the redundant one
6490 -- is the one appearing in the subunit.
6492 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
6493 Redundant
:= Clause
;
6494 Prev_Use
:= Cur_Use
;
6496 -- Most common case: redundant clause in body,
6497 -- original clause in spec. Current scope is spec entity.
6502 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
6504 Redundant
:= Cur_Use
;
6508 -- The new clause may appear in an unrelated unit, when
6509 -- the parents of a generic are being installed prior to
6510 -- instantiation. In this case there must be no warning.
6511 -- We detect this case by checking whether the current top
6512 -- of the stack is related to the current compilation.
6514 Scop
:= Current_Scope
;
6515 while Present
(Scop
)
6516 and then Scop
/= Standard_Standard
6518 if Is_Compilation_Unit
(Scop
)
6519 and then not Is_Child_Unit
(Scop
)
6523 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
6527 Scop
:= Scope
(Scop
);
6530 Redundant
:= Cur_Use
;
6534 elsif New_Unit
= Current_Sem_Unit
then
6535 Redundant
:= Clause
;
6536 Prev_Use
:= Cur_Use
;
6539 -- Neither is the current unit, so they appear in parent or
6540 -- sibling units. Warning will be emitted elsewhere.
6546 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
6547 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
6549 -- Use_clause is in child unit of current unit, and the child unit
6550 -- appears in the context of the body of the parent, so it has been
6551 -- installed first, even though it is the redundant one. Depending on
6552 -- their placement in the context, the visible or the private parts
6553 -- of the two units, either might appear as redundant, but the
6554 -- message has to be on the current unit.
6556 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
6557 Redundant
:= Cur_Use
;
6560 Redundant
:= Clause
;
6561 Prev_Use
:= Cur_Use
;
6564 -- If the new use clause appears in the private part of a parent unit
6565 -- it may appear to be redundant w.r.t. a use clause in a child unit,
6566 -- but the previous use clause was needed in the visible part of the
6567 -- child, and no warning should be emitted.
6569 if Nkind
(Parent
(Decl
)) = N_Package_Specification
6571 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
6574 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
6575 Spec
: constant Node_Id
:=
6576 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
6579 if Is_Compilation_Unit
(Par
)
6580 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
6581 and then Parent
(Cur_Use
) = Spec
6583 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
6590 -- Finally, if the current use clause is in the context then
6591 -- the clause is redundant when it is nested within the unit.
6593 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
6594 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
6595 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
6597 Redundant
:= Clause
;
6598 Prev_Use
:= Cur_Use
;
6604 if Present
(Redundant
) then
6605 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
6606 Error_Msg_NE
-- CODEFIX
6607 ("& is already use-visible through previous use clause #?",
6608 Redundant
, Pack_Name
);
6610 end Note_Redundant_Use
;
6616 procedure Pop_Scope
is
6617 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
6620 if Debug_Flag_E
then
6624 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
6625 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
6626 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
6628 if Debug_Flag_W
then
6629 Write_Str
("--> exiting scope: ");
6630 Write_Name
(Chars
(Current_Scope
));
6631 Write_Str
(", Depth=");
6632 Write_Int
(Int
(Scope_Stack
.Last
));
6636 End_Use_Clauses
(SST
.First_Use_Clause
);
6638 -- If the actions to be wrapped are still there they will get lost
6639 -- causing incomplete code to be generated. It is better to abort in
6640 -- this case (and we do the abort even with assertions off since the
6641 -- penalty is incorrect code generation)
6643 if SST
.Actions_To_Be_Wrapped_Before
/= No_List
6645 SST
.Actions_To_Be_Wrapped_After
/= No_List
6650 -- Free last subprogram name if allocated, and pop scope
6652 Free
(SST
.Last_Subprogram_Name
);
6653 Scope_Stack
.Decrement_Last
;
6660 procedure Push_Scope
(S
: Entity_Id
) is
6664 if Ekind
(S
) = E_Void
then
6667 -- Set scope depth if not a non-concurrent type, and we have not yet set
6668 -- the scope depth. This means that we have the first occurrence of the
6669 -- scope, and this is where the depth is set.
6671 elsif (not Is_Type
(S
) or else Is_Concurrent_Type
(S
))
6672 and then not Scope_Depth_Set
(S
)
6674 if S
= Standard_Standard
then
6675 Set_Scope_Depth_Value
(S
, Uint_0
);
6677 elsif Is_Child_Unit
(S
) then
6678 Set_Scope_Depth_Value
(S
, Uint_1
);
6680 elsif not Is_Record_Type
(Current_Scope
) then
6681 if Ekind
(S
) = E_Loop
then
6682 Set_Scope_Depth_Value
(S
, Scope_Depth
(Current_Scope
));
6684 Set_Scope_Depth_Value
(S
, Scope_Depth
(Current_Scope
) + 1);
6689 Scope_Stack
.Increment_Last
;
6692 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
6696 SST
.Save_Scope_Suppress
:= Scope_Suppress
;
6697 SST
.Save_Local_Suppress_Stack_Top
:= Local_Suppress_Stack_Top
;
6698 SST
.Save_Check_Policy_List
:= Check_Policy_List
;
6700 if Scope_Stack
.Last
> Scope_Stack
.First
then
6701 SST
.Component_Alignment_Default
:= Scope_Stack
.Table
6702 (Scope_Stack
.Last
- 1).
6703 Component_Alignment_Default
;
6706 SST
.Last_Subprogram_Name
:= null;
6707 SST
.Is_Transient
:= False;
6708 SST
.Node_To_Be_Wrapped
:= Empty
;
6709 SST
.Pending_Freeze_Actions
:= No_List
;
6710 SST
.Actions_To_Be_Wrapped_Before
:= No_List
;
6711 SST
.Actions_To_Be_Wrapped_After
:= No_List
;
6712 SST
.First_Use_Clause
:= Empty
;
6713 SST
.Is_Active_Stack_Base
:= False;
6714 SST
.Previous_Visibility
:= False;
6717 if Debug_Flag_W
then
6718 Write_Str
("--> new scope: ");
6719 Write_Name
(Chars
(Current_Scope
));
6720 Write_Str
(", Id=");
6721 Write_Int
(Int
(Current_Scope
));
6722 Write_Str
(", Depth=");
6723 Write_Int
(Int
(Scope_Stack
.Last
));
6727 -- Deal with copying flags from the previous scope to this one. This is
6728 -- not necessary if either scope is standard, or if the new scope is a
6731 if S
/= Standard_Standard
6732 and then Scope
(S
) /= Standard_Standard
6733 and then not Is_Child_Unit
(S
)
6737 if Nkind
(E
) not in N_Entity
then
6741 -- Copy categorization flags from Scope (S) to S, this is not done
6742 -- when Scope (S) is Standard_Standard since propagation is from
6743 -- library unit entity inwards. Copy other relevant attributes as
6744 -- well (Discard_Names in particular).
6746 -- We only propagate inwards for library level entities,
6747 -- inner level subprograms do not inherit the categorization.
6749 if Is_Library_Level_Entity
(S
) then
6750 Set_Is_Preelaborated
(S
, Is_Preelaborated
(E
));
6751 Set_Is_Shared_Passive
(S
, Is_Shared_Passive
(E
));
6752 Set_Discard_Names
(S
, Discard_Names
(E
));
6753 Set_Suppress_Value_Tracking_On_Call
6754 (S
, Suppress_Value_Tracking_On_Call
(E
));
6755 Set_Categorization_From_Scope
(E
=> S
, Scop
=> E
);
6760 ---------------------
6761 -- Premature_Usage --
6762 ---------------------
6764 procedure Premature_Usage
(N
: Node_Id
) is
6765 Kind
: constant Node_Kind
:= Nkind
(Parent
(Entity
(N
)));
6766 E
: Entity_Id
:= Entity
(N
);
6769 -- Within an instance, the analysis of the actual for a formal object
6770 -- does not see the name of the object itself. This is significant only
6771 -- if the object is an aggregate, where its analysis does not do any
6772 -- name resolution on component associations. (see 4717-008). In such a
6773 -- case, look for the visible homonym on the chain.
6776 and then Present
(Homonym
(E
))
6781 and then not In_Open_Scopes
(Scope
(E
))
6788 Set_Etype
(N
, Etype
(E
));
6793 if Kind
= N_Component_Declaration
then
6795 ("component&! cannot be used before end of record declaration", N
);
6797 elsif Kind
= N_Parameter_Specification
then
6799 ("formal parameter&! cannot be used before end of specification",
6802 elsif Kind
= N_Discriminant_Specification
then
6804 ("discriminant&! cannot be used before end of discriminant part",
6807 elsif Kind
= N_Procedure_Specification
6808 or else Kind
= N_Function_Specification
6811 ("subprogram&! cannot be used before end of its declaration",
6814 elsif Kind
= N_Full_Type_Declaration
then
6816 ("type& cannot be used before end of its declaration!", N
);
6820 ("object& cannot be used before end of its declaration!", N
);
6822 end Premature_Usage
;
6824 ------------------------
6825 -- Present_System_Aux --
6826 ------------------------
6828 function Present_System_Aux
(N
: Node_Id
:= Empty
) return Boolean is
6830 Aux_Name
: Unit_Name_Type
;
6831 Unum
: Unit_Number_Type
;
6836 function Find_System
(C_Unit
: Node_Id
) return Entity_Id
;
6837 -- Scan context clause of compilation unit to find with_clause
6844 function Find_System
(C_Unit
: Node_Id
) return Entity_Id
is
6845 With_Clause
: Node_Id
;
6848 With_Clause
:= First
(Context_Items
(C_Unit
));
6849 while Present
(With_Clause
) loop
6850 if (Nkind
(With_Clause
) = N_With_Clause
6851 and then Chars
(Name
(With_Clause
)) = Name_System
)
6852 and then Comes_From_Source
(With_Clause
)
6863 -- Start of processing for Present_System_Aux
6866 -- The child unit may have been loaded and analyzed already
6868 if Present
(System_Aux_Id
) then
6871 -- If no previous pragma for System.Aux, nothing to load
6873 elsif No
(System_Extend_Unit
) then
6876 -- Use the unit name given in the pragma to retrieve the unit.
6877 -- Verify that System itself appears in the context clause of the
6878 -- current compilation. If System is not present, an error will
6879 -- have been reported already.
6882 With_Sys
:= Find_System
(Cunit
(Current_Sem_Unit
));
6884 The_Unit
:= Unit
(Cunit
(Current_Sem_Unit
));
6888 (Nkind
(The_Unit
) = N_Package_Body
6889 or else (Nkind
(The_Unit
) = N_Subprogram_Body
6891 not Acts_As_Spec
(Cunit
(Current_Sem_Unit
))))
6893 With_Sys
:= Find_System
(Library_Unit
(Cunit
(Current_Sem_Unit
)));
6897 and then Present
(N
)
6899 -- If we are compiling a subunit, we need to examine its
6900 -- context as well (Current_Sem_Unit is the parent unit);
6902 The_Unit
:= Parent
(N
);
6903 while Nkind
(The_Unit
) /= N_Compilation_Unit
loop
6904 The_Unit
:= Parent
(The_Unit
);
6907 if Nkind
(Unit
(The_Unit
)) = N_Subunit
then
6908 With_Sys
:= Find_System
(The_Unit
);
6912 if No
(With_Sys
) then
6916 Loc
:= Sloc
(With_Sys
);
6917 Get_Name_String
(Chars
(Expression
(System_Extend_Unit
)));
6918 Name_Buffer
(8 .. Name_Len
+ 7) := Name_Buffer
(1 .. Name_Len
);
6919 Name_Buffer
(1 .. 7) := "system.";
6920 Name_Buffer
(Name_Len
+ 8) := '%';
6921 Name_Buffer
(Name_Len
+ 9) := 's';
6922 Name_Len
:= Name_Len
+ 9;
6923 Aux_Name
:= Name_Find
;
6927 (Load_Name
=> Aux_Name
,
6930 Error_Node
=> With_Sys
);
6932 if Unum
/= No_Unit
then
6933 Semantics
(Cunit
(Unum
));
6935 Defining_Entity
(Specification
(Unit
(Cunit
(Unum
))));
6938 Make_With_Clause
(Loc
,
6940 Make_Expanded_Name
(Loc
,
6941 Chars
=> Chars
(System_Aux_Id
),
6942 Prefix
=> New_Reference_To
(Scope
(System_Aux_Id
), Loc
),
6943 Selector_Name
=> New_Reference_To
(System_Aux_Id
, Loc
)));
6945 Set_Entity
(Name
(Withn
), System_Aux_Id
);
6947 Set_Library_Unit
(Withn
, Cunit
(Unum
));
6948 Set_Corresponding_Spec
(Withn
, System_Aux_Id
);
6949 Set_First_Name
(Withn
, True);
6950 Set_Implicit_With
(Withn
, True);
6952 Insert_After
(With_Sys
, Withn
);
6953 Mark_Rewrite_Insertion
(Withn
);
6954 Set_Context_Installed
(Withn
);
6958 -- Here if unit load failed
6961 Error_Msg_Name_1
:= Name_System
;
6962 Error_Msg_Name_2
:= Chars
(Expression
(System_Extend_Unit
));
6964 ("extension package `%.%` does not exist",
6965 Opt
.System_Extend_Unit
);
6969 end Present_System_Aux
;
6971 -------------------------
6972 -- Restore_Scope_Stack --
6973 -------------------------
6975 procedure Restore_Scope_Stack
(Handle_Use
: Boolean := True) is
6978 Comp_Unit
: Node_Id
;
6979 In_Child
: Boolean := False;
6980 Full_Vis
: Boolean := True;
6981 SS_Last
: constant Int
:= Scope_Stack
.Last
;
6984 -- Restore visibility of previous scope stack, if any
6986 for J
in reverse 0 .. Scope_Stack
.Last
loop
6987 exit when Scope_Stack
.Table
(J
).Entity
= Standard_Standard
6988 or else No
(Scope_Stack
.Table
(J
).Entity
);
6990 S
:= Scope_Stack
.Table
(J
).Entity
;
6992 if not Is_Hidden_Open_Scope
(S
) then
6994 -- If the parent scope is hidden, its entities are hidden as
6995 -- well, unless the entity is the instantiation currently
6998 if not Is_Hidden_Open_Scope
(Scope
(S
))
6999 or else not Analyzed
(Parent
(S
))
7000 or else Scope
(S
) = Standard_Standard
7002 Set_Is_Immediately_Visible
(S
, True);
7005 E
:= First_Entity
(S
);
7006 while Present
(E
) loop
7007 if Is_Child_Unit
(E
) then
7008 if not From_With_Type
(E
) then
7009 Set_Is_Immediately_Visible
(E
,
7010 Is_Visible_Child_Unit
(E
) or else In_Open_Scopes
(E
));
7014 (Nkind
(Parent
(E
)) = N_Defining_Program_Unit_Name
7016 Nkind
(Parent
(Parent
(E
))) = N_Package_Specification
);
7017 Set_Is_Immediately_Visible
(E
,
7018 Limited_View_Installed
(Parent
(Parent
(E
))));
7021 Set_Is_Immediately_Visible
(E
, True);
7027 and then Is_Package_Or_Generic_Package
(S
)
7029 -- We are in the visible part of the package scope
7031 exit when E
= First_Private_Entity
(S
);
7035 -- The visibility of child units (siblings of current compilation)
7036 -- must be restored in any case. Their declarations may appear
7037 -- after the private part of the parent.
7039 if not Full_Vis
then
7040 while Present
(E
) loop
7041 if Is_Child_Unit
(E
) then
7042 Set_Is_Immediately_Visible
(E
,
7043 Is_Visible_Child_Unit
(E
) or else In_Open_Scopes
(E
));
7051 if Is_Child_Unit
(S
)
7052 and not In_Child
-- check only for current unit
7056 -- Restore visibility of parents according to whether the child
7057 -- is private and whether we are in its visible part.
7059 Comp_Unit
:= Parent
(Unit_Declaration_Node
(S
));
7061 if Nkind
(Comp_Unit
) = N_Compilation_Unit
7062 and then Private_Present
(Comp_Unit
)
7066 elsif Is_Package_Or_Generic_Package
(S
)
7067 and then (In_Private_Part
(S
) or else In_Package_Body
(S
))
7071 -- if S is the scope of some instance (which has already been
7072 -- seen on the stack) it does not affect the visibility of
7075 elsif Is_Hidden_Open_Scope
(S
) then
7078 elsif (Ekind
(S
) = E_Procedure
7079 or else Ekind
(S
) = E_Function
)
7080 and then Has_Completion
(S
)
7091 if SS_Last
>= Scope_Stack
.First
7092 and then Scope_Stack
.Table
(SS_Last
).Entity
/= Standard_Standard
7095 Install_Use_Clauses
(Scope_Stack
.Table
(SS_Last
).First_Use_Clause
);
7097 end Restore_Scope_Stack
;
7099 ----------------------
7100 -- Save_Scope_Stack --
7101 ----------------------
7103 procedure Save_Scope_Stack
(Handle_Use
: Boolean := True) is
7106 SS_Last
: constant Int
:= Scope_Stack
.Last
;
7109 if SS_Last
>= Scope_Stack
.First
7110 and then Scope_Stack
.Table
(SS_Last
).Entity
/= Standard_Standard
7113 End_Use_Clauses
(Scope_Stack
.Table
(SS_Last
).First_Use_Clause
);
7116 -- If the call is from within a compilation unit, as when called from
7117 -- Rtsfind, make current entries in scope stack invisible while we
7118 -- analyze the new unit.
7120 for J
in reverse 0 .. SS_Last
loop
7121 exit when Scope_Stack
.Table
(J
).Entity
= Standard_Standard
7122 or else No
(Scope_Stack
.Table
(J
).Entity
);
7124 S
:= Scope_Stack
.Table
(J
).Entity
;
7125 Set_Is_Immediately_Visible
(S
, False);
7127 E
:= First_Entity
(S
);
7128 while Present
(E
) loop
7129 Set_Is_Immediately_Visible
(E
, False);
7135 end Save_Scope_Stack
;
7141 procedure Set_Use
(L
: List_Id
) is
7143 Pack_Name
: Node_Id
;
7150 while Present
(Decl
) loop
7151 if Nkind
(Decl
) = N_Use_Package_Clause
then
7152 Chain_Use_Clause
(Decl
);
7154 Pack_Name
:= First
(Names
(Decl
));
7155 while Present
(Pack_Name
) loop
7156 Pack
:= Entity
(Pack_Name
);
7158 if Ekind
(Pack
) = E_Package
7159 and then Applicable_Use
(Pack_Name
)
7161 Use_One_Package
(Pack
, Decl
);
7167 elsif Nkind
(Decl
) = N_Use_Type_Clause
then
7168 Chain_Use_Clause
(Decl
);
7170 Id
:= First
(Subtype_Marks
(Decl
));
7171 while Present
(Id
) loop
7172 if Entity
(Id
) /= Any_Type
then
7185 ---------------------
7186 -- Use_One_Package --
7187 ---------------------
7189 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
) is
7192 Current_Instance
: Entity_Id
:= Empty
;
7194 Private_With_OK
: Boolean := False;
7197 if Ekind
(P
) /= E_Package
then
7202 Set_Current_Use_Clause
(P
, N
);
7204 -- Ada 2005 (AI-50217): Check restriction
7206 if From_With_Type
(P
) then
7207 Error_Msg_N
("limited withed package cannot appear in use clause", N
);
7210 -- Find enclosing instance, if any
7213 Current_Instance
:= Current_Scope
;
7214 while not Is_Generic_Instance
(Current_Instance
) loop
7215 Current_Instance
:= Scope
(Current_Instance
);
7218 if No
(Hidden_By_Use_Clause
(N
)) then
7219 Set_Hidden_By_Use_Clause
(N
, New_Elmt_List
);
7223 -- If unit is a package renaming, indicate that the renamed
7224 -- package is also in use (the flags on both entities must
7225 -- remain consistent, and a subsequent use of either of them
7226 -- should be recognized as redundant).
7228 if Present
(Renamed_Object
(P
)) then
7229 Set_In_Use
(Renamed_Object
(P
));
7230 Set_Current_Use_Clause
(Renamed_Object
(P
), N
);
7231 Real_P
:= Renamed_Object
(P
);
7236 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
7237 -- found in the private part of a package specification
7239 if In_Private_Part
(Current_Scope
)
7240 and then Has_Private_With
(P
)
7241 and then Is_Child_Unit
(Current_Scope
)
7242 and then Is_Child_Unit
(P
)
7243 and then Is_Ancestor_Package
(Scope
(Current_Scope
), P
)
7245 Private_With_OK
:= True;
7248 -- Loop through entities in one package making them potentially
7251 Id
:= First_Entity
(P
);
7253 and then (Id
/= First_Private_Entity
(P
)
7254 or else Private_With_OK
) -- Ada 2005 (AI-262)
7256 Prev
:= Current_Entity
(Id
);
7257 while Present
(Prev
) loop
7258 if Is_Immediately_Visible
(Prev
)
7259 and then (not Is_Overloadable
(Prev
)
7260 or else not Is_Overloadable
(Id
)
7261 or else (Type_Conformant
(Id
, Prev
)))
7263 if No
(Current_Instance
) then
7265 -- Potentially use-visible entity remains hidden
7267 goto Next_Usable_Entity
;
7269 -- A use clause within an instance hides outer global entities,
7270 -- which are not used to resolve local entities in the
7271 -- instance. Note that the predefined entities in Standard
7272 -- could not have been hidden in the generic by a use clause,
7273 -- and therefore remain visible. Other compilation units whose
7274 -- entities appear in Standard must be hidden in an instance.
7276 -- To determine whether an entity is external to the instance
7277 -- we compare the scope depth of its scope with that of the
7278 -- current instance. However, a generic actual of a subprogram
7279 -- instance is declared in the wrapper package but will not be
7280 -- hidden by a use-visible entity. similarly, an entity that is
7281 -- declared in an enclosing instance will not be hidden by an
7282 -- an entity declared in a generic actual, which can only have
7283 -- been use-visible in the generic and will not have hidden the
7284 -- entity in the generic parent.
7286 -- If Id is called Standard, the predefined package with the
7287 -- same name is in the homonym chain. It has to be ignored
7288 -- because it has no defined scope (being the only entity in
7289 -- the system with this mandated behavior).
7291 elsif not Is_Hidden
(Id
)
7292 and then Present
(Scope
(Prev
))
7293 and then not Is_Wrapper_Package
(Scope
(Prev
))
7294 and then Scope_Depth
(Scope
(Prev
)) <
7295 Scope_Depth
(Current_Instance
)
7296 and then (Scope
(Prev
) /= Standard_Standard
7297 or else Sloc
(Prev
) > Standard_Location
)
7299 if In_Open_Scopes
(Scope
(Prev
))
7300 and then Is_Generic_Instance
(Scope
(Prev
))
7301 and then Present
(Associated_Formal_Package
(P
))
7306 Set_Is_Potentially_Use_Visible
(Id
);
7307 Set_Is_Immediately_Visible
(Prev
, False);
7308 Append_Elmt
(Prev
, Hidden_By_Use_Clause
(N
));
7312 -- A user-defined operator is not use-visible if the predefined
7313 -- operator for the type is immediately visible, which is the case
7314 -- if the type of the operand is in an open scope. This does not
7315 -- apply to user-defined operators that have operands of different
7316 -- types, because the predefined mixed mode operations (multiply
7317 -- and divide) apply to universal types and do not hide anything.
7319 elsif Ekind
(Prev
) = E_Operator
7320 and then Operator_Matches_Spec
(Prev
, Id
)
7321 and then In_Open_Scopes
7322 (Scope
(Base_Type
(Etype
(First_Formal
(Id
)))))
7323 and then (No
(Next_Formal
(First_Formal
(Id
)))
7324 or else Etype
(First_Formal
(Id
))
7325 = Etype
(Next_Formal
(First_Formal
(Id
)))
7326 or else Chars
(Prev
) = Name_Op_Expon
)
7328 goto Next_Usable_Entity
;
7330 -- In an instance, two homonyms may become use_visible through the
7331 -- actuals of distinct formal packages. In the generic, only the
7332 -- current one would have been visible, so make the other one
7335 elsif Present
(Current_Instance
)
7336 and then Is_Potentially_Use_Visible
(Prev
)
7337 and then not Is_Overloadable
(Prev
)
7338 and then Scope
(Id
) /= Scope
(Prev
)
7339 and then Used_As_Generic_Actual
(Scope
(Prev
))
7340 and then Used_As_Generic_Actual
(Scope
(Id
))
7341 and then not In_Same_List
(Current_Use_Clause
(Scope
(Prev
)),
7342 Current_Use_Clause
(Scope
(Id
)))
7344 Set_Is_Potentially_Use_Visible
(Prev
, False);
7345 Append_Elmt
(Prev
, Hidden_By_Use_Clause
(N
));
7348 Prev
:= Homonym
(Prev
);
7351 -- On exit, we know entity is not hidden, unless it is private
7353 if not Is_Hidden
(Id
)
7354 and then ((not Is_Child_Unit
(Id
))
7355 or else Is_Visible_Child_Unit
(Id
))
7357 Set_Is_Potentially_Use_Visible
(Id
);
7359 if Is_Private_Type
(Id
)
7360 and then Present
(Full_View
(Id
))
7362 Set_Is_Potentially_Use_Visible
(Full_View
(Id
));
7366 <<Next_Usable_Entity
>>
7370 -- Child units are also made use-visible by a use clause, but they may
7371 -- appear after all visible declarations in the parent entity list.
7373 while Present
(Id
) loop
7374 if Is_Child_Unit
(Id
)
7375 and then Is_Visible_Child_Unit
(Id
)
7377 Set_Is_Potentially_Use_Visible
(Id
);
7383 if Chars
(Real_P
) = Name_System
7384 and then Scope
(Real_P
) = Standard_Standard
7385 and then Present_System_Aux
(N
)
7387 Use_One_Package
(System_Aux_Id
, N
);
7390 end Use_One_Package
;
7396 procedure Use_One_Type
(Id
: Node_Id
) is
7398 Is_Known_Used
: Boolean;
7402 function Spec_Reloaded_For_Body
return Boolean;
7403 -- Determine whether the compilation unit is a package body and the use
7404 -- type clause is in the spec of the same package. Even though the spec
7405 -- was analyzed first, its context is reloaded when analysing the body.
7407 ----------------------------
7408 -- Spec_Reloaded_For_Body --
7409 ----------------------------
7411 function Spec_Reloaded_For_Body
return Boolean is
7413 if Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7415 Spec
: constant Node_Id
:=
7416 Parent
(List_Containing
(Parent
(Id
)));
7419 Nkind
(Spec
) = N_Package_Specification
7420 and then Corresponding_Body
(Parent
(Spec
)) =
7421 Cunit_Entity
(Current_Sem_Unit
);
7426 end Spec_Reloaded_For_Body
;
7428 -- Start of processing for Use_One_Type;
7431 -- It is the type determined by the subtype mark (8.4(8)) whose
7432 -- operations become potentially use-visible.
7434 T
:= Base_Type
(Entity
(Id
));
7436 -- Either the type itself is used, the package where it is declared
7437 -- is in use or the entity is declared in the current package, thus
7442 or else In_Use
(Scope
(T
))
7443 or else Scope
(T
) = Current_Scope
;
7445 Set_Redundant_Use
(Id
,
7446 Is_Known_Used
or else Is_Potentially_Use_Visible
(T
));
7448 if Ekind
(T
) = E_Incomplete_Type
then
7449 Error_Msg_N
("premature usage of incomplete type", Id
);
7451 elsif In_Open_Scopes
(Scope
(T
)) then
7454 -- A limited view cannot appear in a use_type clause. However, an access
7455 -- type whose designated type is limited has the flag but is not itself
7456 -- a limited view unless we only have a limited view of its enclosing
7459 elsif From_With_Type
(T
)
7460 and then From_With_Type
(Scope
(T
))
7463 ("incomplete type from limited view "
7464 & "cannot appear in use clause", Id
);
7466 -- If the subtype mark designates a subtype in a different package,
7467 -- we have to check that the parent type is visible, otherwise the
7468 -- use type clause is a noop. Not clear how to do that???
7470 elsif not Redundant_Use
(Id
) then
7473 -- If T is tagged, primitive operators on class-wide operands
7474 -- are also available.
7476 if Is_Tagged_Type
(T
) then
7477 Set_In_Use
(Class_Wide_Type
(T
));
7480 Set_Current_Use_Clause
(T
, Parent
(Id
));
7481 Op_List
:= Collect_Primitive_Operations
(T
);
7483 Elmt
:= First_Elmt
(Op_List
);
7484 while Present
(Elmt
) loop
7485 if (Nkind
(Node
(Elmt
)) = N_Defining_Operator_Symbol
7486 or else Chars
(Node
(Elmt
)) in Any_Operator_Name
)
7487 and then not Is_Hidden
(Node
(Elmt
))
7489 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
7496 -- If warning on redundant constructs, check for unnecessary WITH
7498 if Warn_On_Redundant_Constructs
7499 and then Is_Known_Used
7501 -- with P; with P; use P;
7502 -- package P is package X is package body X is
7503 -- type T ... use P.T;
7505 -- The compilation unit is the body of X. GNAT first compiles the
7506 -- spec of X, then proceeds to the body. At that point P is marked
7507 -- as use visible. The analysis then reinstalls the spec along with
7508 -- its context. The use clause P.T is now recognized as redundant,
7509 -- but in the wrong context. Do not emit a warning in such cases.
7510 -- Do not emit a warning either if we are in an instance, there is
7511 -- no redundancy between an outer use_clause and one that appears
7512 -- within the generic.
7514 and then not Spec_Reloaded_For_Body
7515 and then not In_Instance
7517 -- The type already has a use clause
7521 -- Case where we know the current use clause for the type
7523 if Present
(Current_Use_Clause
(T
)) then
7524 Use_Clause_Known
: declare
7525 Clause1
: constant Node_Id
:= Parent
(Id
);
7526 Clause2
: constant Node_Id
:= Current_Use_Clause
(T
);
7533 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
;
7534 -- Return the appropriate entity for determining which unit
7535 -- has a deeper scope: the defining entity for U, unless U
7536 -- is a package instance, in which case we retrieve the
7537 -- entity of the instance spec.
7539 --------------------
7540 -- Entity_Of_Unit --
7541 --------------------
7543 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
is
7545 if Nkind
(U
) = N_Package_Instantiation
7546 and then Analyzed
(U
)
7548 return Defining_Entity
(Instance_Spec
(U
));
7550 return Defining_Entity
(U
);
7554 -- Start of processing for Use_Clause_Known
7557 -- If both current use type clause and the use type clause
7558 -- for the type are at the compilation unit level, one of
7559 -- the units must be an ancestor of the other, and the
7560 -- warning belongs on the descendant.
7562 if Nkind
(Parent
(Clause1
)) = N_Compilation_Unit
7564 Nkind
(Parent
(Clause2
)) = N_Compilation_Unit
7567 -- If the unit is a subprogram body that acts as spec,
7568 -- the context clause is shared with the constructed
7569 -- subprogram spec. Clearly there is no redundancy.
7571 if Clause1
= Clause2
then
7575 Unit1
:= Unit
(Parent
(Clause1
));
7576 Unit2
:= Unit
(Parent
(Clause2
));
7578 -- If both clauses are on same unit, or one is the body
7579 -- of the other, or one of them is in a subunit, report
7580 -- redundancy on the later one.
7582 if Unit1
= Unit2
then
7583 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7584 Error_Msg_NE
-- CODEFIX
7585 ("& is already use-visible through previous "
7586 & "use_type_clause #?", Clause1
, T
);
7589 elsif Nkind
(Unit1
) = N_Subunit
then
7590 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7591 Error_Msg_NE
-- CODEFIX
7592 ("& is already use-visible through previous "
7593 & "use_type_clause #?", Clause1
, T
);
7596 elsif Nkind_In
(Unit2
, N_Package_Body
, N_Subprogram_Body
)
7597 and then Nkind
(Unit1
) /= Nkind
(Unit2
)
7598 and then Nkind
(Unit1
) /= N_Subunit
7600 Error_Msg_Sloc
:= Sloc
(Clause1
);
7601 Error_Msg_NE
-- CODEFIX
7602 ("& is already use-visible through previous "
7603 & "use_type_clause #?", Current_Use_Clause
(T
), T
);
7607 -- There is a redundant use type clause in a child unit.
7608 -- Determine which of the units is more deeply nested.
7609 -- If a unit is a package instance, retrieve the entity
7610 -- and its scope from the instance spec.
7612 Ent1
:= Entity_Of_Unit
(Unit1
);
7613 Ent2
:= Entity_Of_Unit
(Unit2
);
7615 if Scope
(Ent2
) = Standard_Standard
then
7616 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7619 elsif Scope
(Ent1
) = Standard_Standard
then
7620 Error_Msg_Sloc
:= Sloc
(Id
);
7623 -- If both units are child units, we determine which one
7624 -- is the descendant by the scope distance to the
7625 -- ultimate parent unit.
7635 and then Present
(S2
)
7636 and then S1
/= Standard_Standard
7637 and then S2
/= Standard_Standard
7643 if S1
= Standard_Standard
then
7644 Error_Msg_Sloc
:= Sloc
(Id
);
7647 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7653 Error_Msg_NE
-- CODEFIX
7654 ("& is already use-visible through previous "
7655 & "use_type_clause #?", Err_No
, Id
);
7657 -- Case where current use type clause and the use type
7658 -- clause for the type are not both at the compilation unit
7659 -- level. In this case we don't have location information.
7662 Error_Msg_NE
-- CODEFIX
7663 ("& is already use-visible through previous "
7664 & "use type clause?", Id
, T
);
7666 end Use_Clause_Known
;
7668 -- Here if Current_Use_Clause is not set for T, another case
7669 -- where we do not have the location information available.
7672 Error_Msg_NE
-- CODEFIX
7673 ("& is already use-visible through previous "
7674 & "use type clause?", Id
, T
);
7677 -- The package where T is declared is already used
7679 elsif In_Use
(Scope
(T
)) then
7680 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(Scope
(T
)));
7681 Error_Msg_NE
-- CODEFIX
7682 ("& is already use-visible through package use clause #?",
7685 -- The current scope is the package where T is declared
7688 Error_Msg_Node_2
:= Scope
(T
);
7689 Error_Msg_NE
-- CODEFIX
7690 ("& is already use-visible inside package &?", Id
, T
);
7699 procedure Write_Info
is
7700 Id
: Entity_Id
:= First_Entity
(Current_Scope
);
7703 -- No point in dumping standard entities
7705 if Current_Scope
= Standard_Standard
then
7709 Write_Str
("========================================================");
7711 Write_Str
(" Defined Entities in ");
7712 Write_Name
(Chars
(Current_Scope
));
7714 Write_Str
("========================================================");
7718 Write_Str
("-- none --");
7722 while Present
(Id
) loop
7723 Write_Entity_Info
(Id
, " ");
7728 if Scope
(Current_Scope
) = Standard_Standard
then
7730 -- Print information on the current unit itself
7732 Write_Entity_Info
(Current_Scope
, " ");
7745 for J
in reverse 1 .. Scope_Stack
.Last
loop
7746 S
:= Scope_Stack
.Table
(J
).Entity
;
7747 Write_Int
(Int
(S
));
7748 Write_Str
(" === ");
7749 Write_Name
(Chars
(S
));