1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Disp
; use Exp_Disp
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Freeze
; use Freeze
;
35 with Ghost
; use Ghost
;
36 with Impunit
; use Impunit
;
38 with Lib
.Load
; use Lib
.Load
;
39 with Lib
.Xref
; use Lib
.Xref
;
40 with Namet
; use Namet
;
41 with Namet
.Sp
; use Namet
.Sp
;
42 with Nlists
; use Nlists
;
43 with Nmake
; use Nmake
;
45 with Output
; use Output
;
46 with Restrict
; use Restrict
;
47 with Rident
; use Rident
;
48 with Rtsfind
; use Rtsfind
;
50 with Sem_Aux
; use Sem_Aux
;
51 with Sem_Cat
; use Sem_Cat
;
52 with Sem_Ch3
; use Sem_Ch3
;
53 with Sem_Ch4
; use Sem_Ch4
;
54 with Sem_Ch6
; use Sem_Ch6
;
55 with Sem_Ch12
; use Sem_Ch12
;
56 with Sem_Ch13
; use Sem_Ch13
;
57 with Sem_Dim
; use Sem_Dim
;
58 with Sem_Disp
; use Sem_Disp
;
59 with Sem_Dist
; use Sem_Dist
;
60 with Sem_Elab
; use Sem_Elab
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Prag
; use Sem_Prag
;
63 with Sem_Res
; use Sem_Res
;
64 with Sem_Util
; use Sem_Util
;
65 with Sem_Type
; use Sem_Type
;
66 with Stand
; use Stand
;
67 with Sinfo
; use Sinfo
;
68 with Sinfo
.CN
; use Sinfo
.CN
;
69 with Snames
; use Snames
;
72 with Tbuild
; use Tbuild
;
73 with Uintp
; use Uintp
;
75 package body Sem_Ch8
is
77 ------------------------------------
78 -- Visibility and Name Resolution --
79 ------------------------------------
81 -- This package handles name resolution and the collection of possible
82 -- interpretations for overloaded names, prior to overload resolution.
84 -- Name resolution is the process that establishes a mapping between source
85 -- identifiers and the entities they denote at each point in the program.
86 -- Each entity is represented by a defining occurrence. Each identifier
87 -- that denotes an entity points to the corresponding defining occurrence.
88 -- This is the entity of the applied occurrence. Each occurrence holds
89 -- an index into the names table, where source identifiers are stored.
91 -- Each entry in the names table for an identifier or designator uses the
92 -- Info pointer to hold a link to the currently visible entity that has
93 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
94 -- in package Sem_Util). The visibility is initialized at the beginning of
95 -- semantic processing to make entities in package Standard immediately
96 -- visible. The visibility table is used in a more subtle way when
97 -- compiling subunits (see below).
99 -- Entities that have the same name (i.e. homonyms) are chained. In the
100 -- case of overloaded entities, this chain holds all the possible meanings
101 -- of a given identifier. The process of overload resolution uses type
102 -- information to select from this chain the unique meaning of a given
105 -- Entities are also chained in their scope, through the Next_Entity link.
106 -- As a consequence, the name space is organized as a sparse matrix, where
107 -- each row corresponds to a scope, and each column to a source identifier.
108 -- Open scopes, that is to say scopes currently being compiled, have their
109 -- corresponding rows of entities in order, innermost scope first.
111 -- The scopes of packages that are mentioned in context clauses appear in
112 -- no particular order, interspersed among open scopes. This is because
113 -- in the course of analyzing the context of a compilation, a package
114 -- declaration is first an open scope, and subsequently an element of the
115 -- context. If subunits or child units are present, a parent unit may
116 -- appear under various guises at various times in the compilation.
118 -- When the compilation of the innermost scope is complete, the entities
119 -- defined therein are no longer visible. If the scope is not a package
120 -- declaration, these entities are never visible subsequently, and can be
121 -- removed from visibility chains. If the scope is a package declaration,
122 -- its visible declarations may still be accessible. Therefore the entities
123 -- defined in such a scope are left on the visibility chains, and only
124 -- their visibility (immediately visibility or potential use-visibility)
127 -- The ordering of homonyms on their chain does not necessarily follow
128 -- the order of their corresponding scopes on the scope stack. For
129 -- example, if package P and the enclosing scope both contain entities
130 -- named E, then when compiling the package body the chain for E will
131 -- hold the global entity first, and the local one (corresponding to
132 -- the current inner scope) next. As a result, name resolution routines
133 -- do not assume any relative ordering of the homonym chains, either
134 -- for scope nesting or to order of appearance of context clauses.
136 -- When compiling a child unit, entities in the parent scope are always
137 -- immediately visible. When compiling the body of a child unit, private
138 -- entities in the parent must also be made immediately visible. There
139 -- are separate routines to make the visible and private declarations
140 -- visible at various times (see package Sem_Ch7).
142 -- +--------+ +-----+
143 -- | In use |-------->| EU1 |-------------------------->
144 -- +--------+ +-----+
146 -- +--------+ +-----+ +-----+
147 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
148 -- +--------+ +-----+ +-----+
150 -- +---------+ | +-----+
151 -- | with'ed |------------------------------>| EW2 |--->
152 -- +---------+ | +-----+
154 -- +--------+ +-----+ +-----+
155 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
156 -- +--------+ +-----+ +-----+
158 -- +--------+ +-----+ +-----+
159 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
160 -- +--------+ +-----+ +-----+
164 -- | | with'ed |----------------------------------------->
168 -- (innermost first) | |
169 -- +----------------------------+
170 -- Names table => | Id1 | | | | Id2 |
171 -- +----------------------------+
173 -- Name resolution must deal with several syntactic forms: simple names,
174 -- qualified names, indexed names, and various forms of calls.
176 -- Each identifier points to an entry in the names table. The resolution
177 -- of a simple name consists in traversing the homonym chain, starting
178 -- from the names table. If an entry is immediately visible, it is the one
179 -- designated by the identifier. If only potentially use-visible entities
180 -- are on the chain, we must verify that they do not hide each other. If
181 -- the entity we find is overloadable, we collect all other overloadable
182 -- entities on the chain as long as they are not hidden.
184 -- To resolve expanded names, we must find the entity at the intersection
185 -- of the entity chain for the scope (the prefix) and the homonym chain
186 -- for the selector. In general, homonym chains will be much shorter than
187 -- entity chains, so it is preferable to start from the names table as
188 -- well. If the entity found is overloadable, we must collect all other
189 -- interpretations that are defined in the scope denoted by the prefix.
191 -- For records, protected types, and tasks, their local entities are
192 -- removed from visibility chains on exit from the corresponding scope.
193 -- From the outside, these entities are always accessed by selected
194 -- notation, and the entity chain for the record type, protected type,
195 -- etc. is traversed sequentially in order to find the designated entity.
197 -- The discriminants of a type and the operations of a protected type or
198 -- task are unchained on exit from the first view of the type, (such as
199 -- a private or incomplete type declaration, or a protected type speci-
200 -- fication) and re-chained when compiling the second view.
202 -- In the case of operators, we do not make operators on derived types
203 -- explicit. As a result, the notation P."+" may denote either a user-
204 -- defined function with name "+", or else an implicit declaration of the
205 -- operator "+" in package P. The resolution of expanded names always
206 -- tries to resolve an operator name as such an implicitly defined entity,
207 -- in addition to looking for explicit declarations.
209 -- All forms of names that denote entities (simple names, expanded names,
210 -- character literals in some cases) have a Entity attribute, which
211 -- identifies the entity denoted by the name.
213 ---------------------
214 -- The Scope Stack --
215 ---------------------
217 -- The Scope stack keeps track of the scopes currently been compiled.
218 -- Every entity that contains declarations (including records) is placed
219 -- on the scope stack while it is being processed, and removed at the end.
220 -- Whenever a non-package scope is exited, the entities defined therein
221 -- are removed from the visibility table, so that entities in outer scopes
222 -- become visible (see previous description). On entry to Sem, the scope
223 -- stack only contains the package Standard. As usual, subunits complicate
224 -- this picture ever so slightly.
226 -- The Rtsfind mechanism can force a call to Semantics while another
227 -- compilation is in progress. The unit retrieved by Rtsfind must be
228 -- compiled in its own context, and has no access to the visibility of
229 -- the unit currently being compiled. The procedures Save_Scope_Stack and
230 -- Restore_Scope_Stack make entities in current open scopes invisible
231 -- before compiling the retrieved unit, and restore the compilation
232 -- environment afterwards.
234 ------------------------
235 -- Compiling subunits --
236 ------------------------
238 -- Subunits must be compiled in the environment of the corresponding stub,
239 -- that is to say with the same visibility into the parent (and its
240 -- context) that is available at the point of the stub declaration, but
241 -- with the additional visibility provided by the context clause of the
242 -- subunit itself. As a result, compilation of a subunit forces compilation
243 -- of the parent (see description in lib-). At the point of the stub
244 -- declaration, Analyze is called recursively to compile the proper body of
245 -- the subunit, but without reinitializing the names table, nor the scope
246 -- stack (i.e. standard is not pushed on the stack). In this fashion the
247 -- context of the subunit is added to the context of the parent, and the
248 -- subunit is compiled in the correct environment. Note that in the course
249 -- of processing the context of a subunit, Standard will appear twice on
250 -- the scope stack: once for the parent of the subunit, and once for the
251 -- unit in the context clause being compiled. However, the two sets of
252 -- entities are not linked by homonym chains, so that the compilation of
253 -- any context unit happens in a fresh visibility environment.
255 -------------------------------
256 -- Processing of USE Clauses --
257 -------------------------------
259 -- Every defining occurrence has a flag indicating if it is potentially use
260 -- visible. Resolution of simple names examines this flag. The processing
261 -- of use clauses consists in setting this flag on all visible entities
262 -- defined in the corresponding package. On exit from the scope of the use
263 -- clause, the corresponding flag must be reset. However, a package may
264 -- appear in several nested use clauses (pathological but legal, alas)
265 -- which forces us to use a slightly more involved scheme:
267 -- a) The defining occurrence for a package holds a flag -In_Use- to
268 -- indicate that it is currently in the scope of a use clause. If a
269 -- redundant use clause is encountered, then the corresponding occurrence
270 -- of the package name is flagged -Redundant_Use-.
272 -- b) On exit from a scope, the use clauses in its declarative part are
273 -- scanned. The visibility flag is reset in all entities declared in
274 -- package named in a use clause, as long as the package is not flagged
275 -- as being in a redundant use clause (in which case the outer use
276 -- clause is still in effect, and the direct visibility of its entities
277 -- must be retained).
279 -- Note that entities are not removed from their homonym chains on exit
280 -- from the package specification. A subsequent use clause does not need
281 -- to rechain the visible entities, but only to establish their direct
284 -----------------------------------
285 -- Handling private declarations --
286 -----------------------------------
288 -- The principle that each entity has a single defining occurrence clashes
289 -- with the presence of two separate definitions for private types: the
290 -- first is the private type declaration, and second is the full type
291 -- declaration. It is important that all references to the type point to
292 -- the same defining occurrence, namely the first one. To enforce the two
293 -- separate views of the entity, the corresponding information is swapped
294 -- between the two declarations. Outside of the package, the defining
295 -- occurrence only contains the private declaration information, while in
296 -- the private part and the body of the package the defining occurrence
297 -- contains the full declaration. To simplify the swap, the defining
298 -- occurrence that currently holds the private declaration points to the
299 -- full declaration. During semantic processing the defining occurrence
300 -- also points to a list of private dependents, that is to say access types
301 -- or composite types whose designated types or component types are
302 -- subtypes or derived types of the private type in question. After the
303 -- full declaration has been seen, the private dependents are updated to
304 -- indicate that they have full definitions.
306 ------------------------------------
307 -- Handling of Undefined Messages --
308 ------------------------------------
310 -- In normal mode, only the first use of an undefined identifier generates
311 -- a message. The table Urefs is used to record error messages that have
312 -- been issued so that second and subsequent ones do not generate further
313 -- messages. However, the second reference causes text to be added to the
314 -- original undefined message noting "(more references follow)". The
315 -- full error list option (-gnatf) forces messages to be generated for
316 -- every reference and disconnects the use of this table.
318 type Uref_Entry
is record
320 -- Node for identifier for which original message was posted. The
321 -- Chars field of this identifier is used to detect later references
322 -- to the same identifier.
325 -- Records error message Id of original undefined message. Reset to
326 -- No_Error_Msg after the second occurrence, where it is used to add
327 -- text to the original message as described above.
330 -- Set if the message is not visible rather than undefined
333 -- Records location of error message. Used to make sure that we do
334 -- not consider a, b : undefined as two separate instances, which
335 -- would otherwise happen, since the parser converts this sequence
336 -- to a : undefined; b : undefined.
340 package Urefs
is new Table
.Table
(
341 Table_Component_Type
=> Uref_Entry
,
342 Table_Index_Type
=> Nat
,
343 Table_Low_Bound
=> 1,
345 Table_Increment
=> 100,
346 Table_Name
=> "Urefs");
348 Candidate_Renaming
: Entity_Id
;
349 -- Holds a candidate interpretation that appears in a subprogram renaming
350 -- declaration and does not match the given specification, but matches at
351 -- least on the first formal. Allows better error message when given
352 -- specification omits defaulted parameters, a common error.
354 -----------------------
355 -- Local Subprograms --
356 -----------------------
358 procedure Analyze_Generic_Renaming
361 -- Common processing for all three kinds of generic renaming declarations.
362 -- Enter new name and indicate that it renames the generic unit.
364 procedure Analyze_Renamed_Character
368 -- Renamed entity is given by a character literal, which must belong
369 -- to the return type of the new entity. Is_Body indicates whether the
370 -- declaration is a renaming_as_body. If the original declaration has
371 -- already been frozen (because of an intervening body, e.g.) the body of
372 -- the function must be built now. The same applies to the following
373 -- various renaming procedures.
375 procedure Analyze_Renamed_Dereference
379 -- Renamed entity is given by an explicit dereference. Prefix must be a
380 -- conformant access_to_subprogram type.
382 procedure Analyze_Renamed_Entry
386 -- If the renamed entity in a subprogram renaming is an entry or protected
387 -- subprogram, build a body for the new entity whose only statement is a
388 -- call to the renamed entity.
390 procedure Analyze_Renamed_Family_Member
394 -- Used when the renamed entity is an indexed component. The prefix must
395 -- denote an entry family.
397 procedure Analyze_Renamed_Primitive_Operation
401 -- If the renamed entity in a subprogram renaming is a primitive operation
402 -- or a class-wide operation in prefix form, save the target object,
403 -- which must be added to the list of actuals in any subsequent call.
404 -- The renaming operation is intrinsic because the compiler must in
405 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
407 procedure Attribute_Renaming
(N
: Node_Id
);
408 -- Analyze renaming of attribute as subprogram. The renaming declaration N
409 -- is rewritten as a subprogram body that returns the attribute reference
410 -- applied to the formals of the function.
412 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
413 -- Set Entity, with style check if need be. For a discriminant reference,
414 -- replace by the corresponding discriminal, i.e. the parameter of the
415 -- initialization procedure that corresponds to the discriminant.
417 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
418 -- A renaming_as_body may occur after the entity of the original decla-
419 -- ration has been frozen. In that case, the body of the new entity must
420 -- be built now, because the usual mechanism of building the renamed
421 -- body at the point of freezing will not work. Subp is the subprogram
422 -- for which N provides the Renaming_As_Body.
424 procedure Check_In_Previous_With_Clause
427 -- N is a use_package clause and Nam the package name, or N is a use_type
428 -- clause and Nam is the prefix of the type name. In either case, verify
429 -- that the package is visible at that point in the context: either it
430 -- appears in a previous with_clause, or because it is a fully qualified
431 -- name and the root ancestor appears in a previous with_clause.
433 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
434 -- Verify that the entity in a renaming declaration that is a library unit
435 -- is itself a library unit and not a nested unit or subunit. Also check
436 -- that if the renaming is a child unit of a generic parent, then the
437 -- renamed unit must also be a child unit of that parent. Finally, verify
438 -- that a renamed generic unit is not an implicit child declared within
439 -- an instance of the parent.
441 procedure Chain_Use_Clause
(N
: Node_Id
);
442 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
443 -- the proper scope table entry. This is usually the current scope, but it
444 -- will be an inner scope when installing the use clauses of the private
445 -- declarations of a parent unit prior to compiling the private part of a
446 -- child unit. This chain is traversed when installing/removing use clauses
447 -- when compiling a subunit or instantiating a generic body on the fly,
448 -- when it is necessary to save and restore full environments.
450 function Enclosing_Instance
return Entity_Id
;
451 -- In an instance nested within another one, several semantic checks are
452 -- unnecessary because the legality of the nested instance has been checked
453 -- in the enclosing generic unit. This applies in particular to legality
454 -- checks on actuals for formal subprograms of the inner instance, which
455 -- are checked as subprogram renamings, and may be complicated by confusion
456 -- in private/full views. This function returns the instance enclosing the
457 -- current one if there is such, else it returns Empty.
459 -- If the renaming determines the entity for the default of a formal
460 -- subprogram nested within another instance, choose the innermost
461 -- candidate. This is because if the formal has a box, and we are within
462 -- an enclosing instance where some candidate interpretations are local
463 -- to this enclosing instance, we know that the default was properly
464 -- resolved when analyzing the generic, so we prefer the local
465 -- candidates to those that are external. This is not always the case
466 -- but is a reasonable heuristic on the use of nested generics. The
467 -- proper solution requires a full renaming model.
469 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
;
470 -- Return the appropriate entity for determining which unit has a deeper
471 -- scope: the defining entity for U, unless U is a package instance, in
472 -- which case we retrieve the entity of the instance spec.
474 procedure Find_Expanded_Name
(N
: Node_Id
);
475 -- The input is a selected component known to be an expanded name. Verify
476 -- legality of selector given the scope denoted by prefix, and change node
477 -- N into a expanded name with a properly set Entity field.
479 function Find_Most_Prev
(Use_Clause
: Node_Id
) return Node_Id
;
480 -- Find the most previous use clause (that is, the first one to appear in
481 -- the source) by traversing the previous clause chain that exists in both
482 -- N_Use_Package_Clause nodes and N_Use_Type_Clause nodes.
483 -- ??? a better subprogram name is in order
485 function Find_Renamed_Entity
489 Is_Actual
: Boolean := False) return Entity_Id
;
490 -- Find the renamed entity that corresponds to the given parameter profile
491 -- in a subprogram renaming declaration. The renamed entity may be an
492 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
493 -- indicates that the renaming is the one generated for an actual subpro-
494 -- gram in an instance, for which special visibility checks apply.
496 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
497 -- Find a type derived from Character or Wide_Character in the prefix of N.
498 -- Used to resolved qualified names whose selector is a character literal.
500 function Has_Private_With
(E
: Entity_Id
) return Boolean;
501 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
502 -- private with on E.
504 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
505 -- N is an expanded name whose selector is an operator name (e.g. P."+").
506 -- declarative part contains an implicit declaration of an operator if it
507 -- has a declaration of a type to which one of the predefined operators
508 -- apply. The existence of this routine is an implementation artifact. A
509 -- more straightforward but more space-consuming choice would be to make
510 -- all inherited operators explicit in the symbol table.
512 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
513 -- A subprogram defined by a renaming declaration inherits the parameter
514 -- profile of the renamed entity. The subtypes given in the subprogram
515 -- specification are discarded and replaced with those of the renamed
516 -- subprogram, which are then used to recheck the default values.
518 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
519 -- True if it is of a task type, a protected type, or else an access to one
522 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
523 -- Prefix is appropriate for record if it is of a record type, or an access
526 function Most_Descendant_Use_Clause
527 (Clause1
: Entity_Id
;
528 Clause2
: Entity_Id
) return Entity_Id
;
529 -- Determine which use clause parameter is the most descendant in terms of
531 -- ??? a better subprogram name is in order
533 procedure Premature_Usage
(N
: Node_Id
);
534 -- Diagnose usage of an entity before it is visible
536 procedure Use_One_Package
538 Pack_Name
: Entity_Id
:= Empty
;
539 Force
: Boolean := False);
540 -- Make visible entities declared in package P potentially use-visible
541 -- in the current context. Also used in the analysis of subunits, when
542 -- re-installing use clauses of parent units. N is the use_clause that
543 -- names P (and possibly other packages).
545 procedure Use_One_Type
547 Installed
: Boolean := False;
548 Force
: Boolean := False);
549 -- Id is the subtype mark from a use_type_clause. This procedure makes
550 -- the primitive operators of the type potentially use-visible. The
551 -- boolean flag Installed indicates that the clause is being reinstalled
552 -- after previous analysis, and primitive operations are already chained
553 -- on the Used_Operations list of the clause.
555 procedure Write_Info
;
556 -- Write debugging information on entities declared in current scope
558 --------------------------------
559 -- Analyze_Exception_Renaming --
560 --------------------------------
562 -- The language only allows a single identifier, but the tree holds an
563 -- identifier list. The parser has already issued an error message if
564 -- there is more than one element in the list.
566 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
567 Id
: constant Entity_Id
:= Defining_Entity
(N
);
568 Nam
: constant Node_Id
:= Name
(N
);
571 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
576 Set_Ekind
(Id
, E_Exception
);
577 Set_Etype
(Id
, Standard_Exception_Type
);
578 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
580 if Is_Entity_Name
(Nam
)
581 and then Present
(Entity
(Nam
))
582 and then Ekind
(Entity
(Nam
)) = E_Exception
584 if Present
(Renamed_Object
(Entity
(Nam
))) then
585 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
587 Set_Renamed_Object
(Id
, Entity
(Nam
));
590 -- The exception renaming declaration may become Ghost if it renames
593 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
595 Error_Msg_N
("invalid exception name in renaming", Nam
);
598 -- Implementation-defined aspect specifications can appear in a renaming
599 -- declaration, but not language-defined ones. The call to procedure
600 -- Analyze_Aspect_Specifications will take care of this error check.
602 if Has_Aspects
(N
) then
603 Analyze_Aspect_Specifications
(N
, Id
);
605 end Analyze_Exception_Renaming
;
607 ---------------------------
608 -- Analyze_Expanded_Name --
609 ---------------------------
611 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
613 -- If the entity pointer is already set, this is an internal node, or a
614 -- node that is analyzed more than once, after a tree modification. In
615 -- such a case there is no resolution to perform, just set the type. In
616 -- either case, start by analyzing the prefix.
618 Analyze
(Prefix
(N
));
620 if Present
(Entity
(N
)) then
621 if Is_Type
(Entity
(N
)) then
622 Set_Etype
(N
, Entity
(N
));
624 Set_Etype
(N
, Etype
(Entity
(N
)));
628 Find_Expanded_Name
(N
);
631 -- In either case, propagate dimension of entity to expanded name
633 Analyze_Dimension
(N
);
634 end Analyze_Expanded_Name
;
636 ---------------------------------------
637 -- Analyze_Generic_Function_Renaming --
638 ---------------------------------------
640 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
642 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
643 end Analyze_Generic_Function_Renaming
;
645 --------------------------------------
646 -- Analyze_Generic_Package_Renaming --
647 --------------------------------------
649 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
651 -- Test for the Text_IO special unit case here, since we may be renaming
652 -- one of the subpackages of Text_IO, then join common routine.
654 Check_Text_IO_Special_Unit
(Name
(N
));
656 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
657 end Analyze_Generic_Package_Renaming
;
659 ----------------------------------------
660 -- Analyze_Generic_Procedure_Renaming --
661 ----------------------------------------
663 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
665 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
666 end Analyze_Generic_Procedure_Renaming
;
668 ------------------------------
669 -- Analyze_Generic_Renaming --
670 ------------------------------
672 procedure Analyze_Generic_Renaming
676 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
677 Inst
: Boolean := False;
681 if Name
(N
) = Error
then
685 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
687 Generate_Definition
(New_P
);
689 if Current_Scope
/= Standard_Standard
then
690 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
693 if Nkind
(Name
(N
)) = N_Selected_Component
then
694 Check_Generic_Child_Unit
(Name
(N
), Inst
);
699 if not Is_Entity_Name
(Name
(N
)) then
700 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
703 Old_P
:= Entity
(Name
(N
));
707 Set_Ekind
(New_P
, K
);
709 if Etype
(Old_P
) = Any_Type
then
712 elsif Ekind
(Old_P
) /= K
then
713 Error_Msg_N
("invalid generic unit name", Name
(N
));
716 if Present
(Renamed_Object
(Old_P
)) then
717 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
719 Set_Renamed_Object
(New_P
, Old_P
);
722 -- The generic renaming declaration may become Ghost if it renames a
725 Mark_Ghost_Renaming
(N
, Old_P
);
727 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
728 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
730 Set_Etype
(New_P
, Etype
(Old_P
));
731 Set_Has_Completion
(New_P
);
733 if In_Open_Scopes
(Old_P
) then
734 Error_Msg_N
("within its scope, generic denotes its instance", N
);
737 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
738 -- renamings and subsequent instantiations of Unchecked_Conversion.
740 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
741 Set_Is_Intrinsic_Subprogram
742 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
745 Check_Library_Unit_Renaming
(N
, Old_P
);
748 -- Implementation-defined aspect specifications can appear in a renaming
749 -- declaration, but not language-defined ones. The call to procedure
750 -- Analyze_Aspect_Specifications will take care of this error check.
752 if Has_Aspects
(N
) then
753 Analyze_Aspect_Specifications
(N
, New_P
);
755 end Analyze_Generic_Renaming
;
757 -----------------------------
758 -- Analyze_Object_Renaming --
759 -----------------------------
761 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
762 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
763 Loc
: constant Source_Ptr
:= Sloc
(N
);
764 Nam
: constant Node_Id
:= Name
(N
);
769 procedure Check_Constrained_Object
;
770 -- If the nominal type is unconstrained but the renamed object is
771 -- constrained, as can happen with renaming an explicit dereference or
772 -- a function return, build a constrained subtype from the object. If
773 -- the renaming is for a formal in an accept statement, the analysis
774 -- has already established its actual subtype. This is only relevant
775 -- if the renamed object is an explicit dereference.
777 ------------------------------
778 -- Check_Constrained_Object --
779 ------------------------------
781 procedure Check_Constrained_Object
is
782 Typ
: constant Entity_Id
:= Etype
(Nam
);
786 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
787 and then Is_Composite_Type
(Etype
(Nam
))
788 and then not Is_Constrained
(Etype
(Nam
))
789 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
790 and then Expander_Active
792 -- If Actual_Subtype is already set, nothing to do
794 if Ekind_In
(Id
, E_Variable
, E_Constant
)
795 and then Present
(Actual_Subtype
(Id
))
799 -- A renaming of an unchecked union has no actual subtype
801 elsif Is_Unchecked_Union
(Typ
) then
804 -- If a record is limited its size is invariant. This is the case
805 -- in particular with record types with an access discirminant
806 -- that are used in iterators. This is an optimization, but it
807 -- also prevents typing anomalies when the prefix is further
808 -- expanded. Limited types with discriminants are included.
810 elsif Is_Limited_Record
(Typ
)
812 (Ekind
(Typ
) = E_Limited_Private_Type
813 and then Has_Discriminants
(Typ
)
814 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
819 Subt
:= Make_Temporary
(Loc
, 'T');
820 Remove_Side_Effects
(Nam
);
822 Make_Subtype_Declaration
(Loc
,
823 Defining_Identifier
=> Subt
,
824 Subtype_Indication
=>
825 Make_Subtype_From_Expr
(Nam
, Typ
)));
826 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
827 Set_Etype
(Nam
, Subt
);
829 -- Freeze subtype at once, to prevent order of elaboration
830 -- issues in the backend. The renamed object exists, so its
831 -- type is already frozen in any case.
833 Freeze_Before
(N
, Subt
);
836 end Check_Constrained_Object
;
838 -- Start of processing for Analyze_Object_Renaming
845 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
847 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
850 -- The renaming of a component that depends on a discriminant requires
851 -- an actual subtype, because in subsequent use of the object Gigi will
852 -- be unable to locate the actual bounds. This explicit step is required
853 -- when the renaming is generated in removing side effects of an
854 -- already-analyzed expression.
856 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
858 -- The object renaming declaration may become Ghost if it renames a
861 if Is_Entity_Name
(Nam
) then
862 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
866 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
868 if Present
(Dec
) then
869 Insert_Action
(N
, Dec
);
870 T
:= Defining_Identifier
(Dec
);
874 -- Complete analysis of the subtype mark in any case, for ASIS use
876 if Present
(Subtype_Mark
(N
)) then
877 Find_Type
(Subtype_Mark
(N
));
880 elsif Present
(Subtype_Mark
(N
)) then
881 Find_Type
(Subtype_Mark
(N
));
882 T
:= Entity
(Subtype_Mark
(N
));
885 -- The object renaming declaration may become Ghost if it renames a
888 if Is_Entity_Name
(Nam
) then
889 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
892 -- Reject renamings of conversions unless the type is tagged, or
893 -- the conversion is implicit (which can occur for cases of anonymous
894 -- access types in Ada 2012).
896 if Nkind
(Nam
) = N_Type_Conversion
897 and then Comes_From_Source
(Nam
)
898 and then not Is_Tagged_Type
(T
)
901 ("renaming of conversion only allowed for tagged types", Nam
);
906 -- If the renamed object is a function call of a limited type,
907 -- the expansion of the renaming is complicated by the presence
908 -- of various temporaries and subtypes that capture constraints
909 -- of the renamed object. Rewrite node as an object declaration,
910 -- whose expansion is simpler. Given that the object is limited
911 -- there is no copy involved and no performance hit.
913 if Nkind
(Nam
) = N_Function_Call
914 and then Is_Limited_View
(Etype
(Nam
))
915 and then not Is_Constrained
(Etype
(Nam
))
916 and then Comes_From_Source
(N
)
919 Set_Ekind
(Id
, E_Constant
);
921 Make_Object_Declaration
(Loc
,
922 Defining_Identifier
=> Id
,
923 Constant_Present
=> True,
924 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
925 Expression
=> Relocate_Node
(Nam
)));
929 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
930 -- when renaming declaration has a named access type. The Ada 2012
931 -- coverage rules allow an anonymous access type in the context of
932 -- an expected named general access type, but the renaming rules
933 -- require the types to be the same. (An exception is when the type
934 -- of the renaming is also an anonymous access type, which can only
935 -- happen due to a renaming created by the expander.)
937 if Nkind
(Nam
) = N_Type_Conversion
938 and then not Comes_From_Source
(Nam
)
939 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
940 and then Ekind
(T
) /= E_Anonymous_Access_Type
942 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
945 -- Check that a class-wide object is not being renamed as an object
946 -- of a specific type. The test for access types is needed to exclude
947 -- cases where the renamed object is a dynamically tagged access
948 -- result, such as occurs in certain expansions.
950 if Is_Tagged_Type
(T
) then
951 Check_Dynamically_Tagged_Expression
957 -- Ada 2005 (AI-230/AI-254): Access renaming
959 else pragma Assert
(Present
(Access_Definition
(N
)));
963 N
=> Access_Definition
(N
));
967 -- The object renaming declaration may become Ghost if it renames a
970 if Is_Entity_Name
(Nam
) then
971 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
974 -- Ada 2005 AI05-105: if the declaration has an anonymous access
975 -- type, the renamed object must also have an anonymous type, and
976 -- this is a name resolution rule. This was implicit in the last part
977 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
980 if not Is_Overloaded
(Nam
) then
981 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
983 ("expect anonymous access type in object renaming", N
);
990 Typ
: Entity_Id
:= Empty
;
991 Seen
: Boolean := False;
994 Get_First_Interp
(Nam
, I
, It
);
995 while Present
(It
.Typ
) loop
997 -- Renaming is ambiguous if more than one candidate
998 -- interpretation is type-conformant with the context.
1000 if Ekind
(It
.Typ
) = Ekind
(T
) then
1001 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
1004 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
1010 ("ambiguous expression in renaming", Nam
);
1013 elsif Ekind
(T
) = E_Anonymous_Access_Type
1015 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1021 ("ambiguous expression in renaming", Nam
);
1025 if Covers
(T
, It
.Typ
) then
1027 Set_Etype
(Nam
, Typ
);
1028 Set_Is_Overloaded
(Nam
, False);
1032 Get_Next_Interp
(I
, It
);
1039 -- Do not perform the legality checks below when the resolution of
1040 -- the renaming name failed because the associated type is Any_Type.
1042 if Etype
(Nam
) = Any_Type
then
1045 -- Ada 2005 (AI-231): In the case where the type is defined by an
1046 -- access_definition, the renamed entity shall be of an access-to-
1047 -- constant type if and only if the access_definition defines an
1048 -- access-to-constant type. ARM 8.5.1(4)
1050 elsif Constant_Present
(Access_Definition
(N
))
1051 and then not Is_Access_Constant
(Etype
(Nam
))
1054 ("(Ada 2005): the renamed object is not access-to-constant "
1055 & "(RM 8.5.1(6))", N
);
1057 elsif not Constant_Present
(Access_Definition
(N
))
1058 and then Is_Access_Constant
(Etype
(Nam
))
1061 ("(Ada 2005): the renamed object is not access-to-variable "
1062 & "(RM 8.5.1(6))", N
);
1065 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1066 Check_Subtype_Conformant
1067 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1069 elsif not Subtypes_Statically_Match
1070 (Designated_Type
(T
),
1071 Available_View
(Designated_Type
(Etype
(Nam
))))
1074 ("subtype of renamed object does not statically match", N
);
1078 -- Special processing for renaming function return object. Some errors
1079 -- and warnings are produced only for calls that come from source.
1081 if Nkind
(Nam
) = N_Function_Call
then
1084 -- Usage is illegal in Ada 83, but renamings are also introduced
1085 -- during expansion, and error does not apply to those.
1088 if Comes_From_Source
(N
) then
1090 ("(Ada 83) cannot rename function return object", Nam
);
1093 -- In Ada 95, warn for odd case of renaming parameterless function
1094 -- call if this is not a limited type (where this is useful).
1097 if Warn_On_Object_Renames_Function
1098 and then No
(Parameter_Associations
(Nam
))
1099 and then not Is_Limited_Type
(Etype
(Nam
))
1100 and then Comes_From_Source
(Nam
)
1103 ("renaming function result object is suspicious?R?", Nam
);
1105 ("\function & will be called only once?R?", Nam
,
1106 Entity
(Name
(Nam
)));
1107 Error_Msg_N
-- CODEFIX
1108 ("\suggest using an initialized constant object "
1109 & "instead?R?", Nam
);
1114 Check_Constrained_Object
;
1116 -- An object renaming requires an exact match of the type. Class-wide
1117 -- matching is not allowed.
1119 if Is_Class_Wide_Type
(T
)
1120 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1122 Wrong_Type
(Nam
, T
);
1127 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1129 if Nkind
(Nam
) = N_Explicit_Dereference
1130 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1132 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1135 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1136 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1140 -- Ada 2005 (AI-327)
1142 if Ada_Version
>= Ada_2005
1143 and then Nkind
(Nam
) = N_Attribute_Reference
1144 and then Attribute_Name
(Nam
) = Name_Priority
1148 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1151 Nam_Ent
: Entity_Id
;
1154 if Nkind
(Nam
) = N_Attribute_Reference
then
1155 Nam_Ent
:= Entity
(Prefix
(Nam
));
1157 Nam_Ent
:= Entity
(Nam
);
1160 Nam_Decl
:= Parent
(Nam_Ent
);
1162 if Has_Null_Exclusion
(N
)
1163 and then not Has_Null_Exclusion
(Nam_Decl
)
1165 -- Ada 2005 (AI-423): If the object name denotes a generic
1166 -- formal object of a generic unit G, and the object renaming
1167 -- declaration occurs within the body of G or within the body
1168 -- of a generic unit declared within the declarative region
1169 -- of G, then the declaration of the formal object of G must
1170 -- have a null exclusion or a null-excluding subtype.
1172 if Is_Formal_Object
(Nam_Ent
)
1173 and then In_Generic_Scope
(Id
)
1175 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1177 ("renamed formal does not exclude `NULL` "
1178 & "(RM 8.5.1(4.6/2))", N
);
1180 elsif In_Package_Body
(Scope
(Id
)) then
1182 ("formal object does not have a null exclusion"
1183 & "(RM 8.5.1(4.6/2))", N
);
1186 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1187 -- shall exclude null.
1189 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1191 ("renamed object does not exclude `NULL` "
1192 & "(RM 8.5.1(4.6/2))", N
);
1194 -- An instance is illegal if it contains a renaming that
1195 -- excludes null, and the actual does not. The renaming
1196 -- declaration has already indicated that the declaration
1197 -- of the renamed actual in the instance will raise
1198 -- constraint_error.
1200 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1201 and then In_Instance
1203 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1204 and then Nkind
(Expression
(Nam_Decl
)) =
1205 N_Raise_Constraint_Error
1208 ("renamed actual does not exclude `NULL` "
1209 & "(RM 8.5.1(4.6/2))", N
);
1211 -- Finally, if there is a null exclusion, the subtype mark
1212 -- must not be null-excluding.
1214 elsif No
(Access_Definition
(N
))
1215 and then Can_Never_Be_Null
(T
)
1218 ("`NOT NULL` not allowed (& already excludes null)",
1223 elsif Can_Never_Be_Null
(T
)
1224 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1227 ("renamed object does not exclude `NULL` "
1228 & "(RM 8.5.1(4.6/2))", N
);
1230 elsif Has_Null_Exclusion
(N
)
1231 and then No
(Access_Definition
(N
))
1232 and then Can_Never_Be_Null
(T
)
1235 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1240 -- Set the Ekind of the entity, unless it has been set already, as is
1241 -- the case for the iteration object over a container with no variable
1242 -- indexing. In that case it's been marked as a constant, and we do not
1243 -- want to change it to a variable.
1245 if Ekind
(Id
) /= E_Constant
then
1246 Set_Ekind
(Id
, E_Variable
);
1249 -- Initialize the object size and alignment. Note that we used to call
1250 -- Init_Size_Align here, but that's wrong for objects which have only
1251 -- an Esize, not an RM_Size field.
1253 Init_Object_Size_Align
(Id
);
1255 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1258 -- Verify that the renamed entity is an object or a function call. It
1259 -- may have been rewritten in several ways.
1261 elsif Is_Object_Reference
(Nam
) then
1262 if Comes_From_Source
(N
) then
1263 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1265 ("illegal renaming of discriminant-dependent component", Nam
);
1268 -- If the renaming comes from source and the renamed object is a
1269 -- dereference, then mark the prefix as needing debug information,
1270 -- since it might have been rewritten hence internally generated
1271 -- and Debug_Renaming_Declaration will link the renaming to it.
1273 if Nkind
(Nam
) = N_Explicit_Dereference
1274 and then Is_Entity_Name
(Prefix
(Nam
))
1276 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1280 -- A static function call may have been folded into a literal
1282 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1284 -- When expansion is disabled, attribute reference is not rewritten
1285 -- as function call. Otherwise it may be rewritten as a conversion,
1286 -- so check original node.
1288 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1289 and then Is_Function_Attribute_Name
1290 (Attribute_Name
(Original_Node
(Nam
))))
1292 -- Weird but legal, equivalent to renaming a function call. Illegal
1293 -- if the literal is the result of constant-folding an attribute
1294 -- reference that is not a function.
1296 or else (Is_Entity_Name
(Nam
)
1297 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1299 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1301 or else (Nkind
(Nam
) = N_Type_Conversion
1302 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1306 elsif Nkind
(Nam
) = N_Type_Conversion
then
1308 ("renaming of conversion only allowed for tagged types", Nam
);
1310 -- Ada 2005 (AI-327)
1312 elsif Ada_Version
>= Ada_2005
1313 and then Nkind
(Nam
) = N_Attribute_Reference
1314 and then Attribute_Name
(Nam
) = Name_Priority
1318 -- Allow internally generated x'Ref resulting in N_Reference node
1320 elsif Nkind
(Nam
) = N_Reference
then
1324 Error_Msg_N
("expect object name in renaming", Nam
);
1329 if not Is_Variable
(Nam
) then
1330 Set_Ekind
(Id
, E_Constant
);
1331 Set_Never_Set_In_Source
(Id
, True);
1332 Set_Is_True_Constant
(Id
, True);
1335 -- The entity of the renaming declaration needs to reflect whether the
1336 -- renamed object is volatile. Is_Volatile is set if the renamed object
1337 -- is volatile in the RM legality sense.
1339 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1341 -- Also copy settings of Atomic/Independent/Volatile_Full_Access
1343 if Is_Entity_Name
(Nam
) then
1344 Set_Is_Atomic
(Id
, Is_Atomic
(Entity
(Nam
)));
1345 Set_Is_Independent
(Id
, Is_Independent
(Entity
(Nam
)));
1346 Set_Is_Volatile_Full_Access
(Id
,
1347 Is_Volatile_Full_Access
(Entity
(Nam
)));
1350 -- Treat as volatile if we just set the Volatile flag
1354 -- Or if we are renaming an entity which was marked this way
1356 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1358 or else (Is_Entity_Name
(Nam
)
1359 and then Treat_As_Volatile
(Entity
(Nam
)))
1361 Set_Treat_As_Volatile
(Id
, True);
1364 -- Now make the link to the renamed object
1366 Set_Renamed_Object
(Id
, Nam
);
1368 -- Implementation-defined aspect specifications can appear in a renaming
1369 -- declaration, but not language-defined ones. The call to procedure
1370 -- Analyze_Aspect_Specifications will take care of this error check.
1372 if Has_Aspects
(N
) then
1373 Analyze_Aspect_Specifications
(N
, Id
);
1376 -- Deal with dimensions
1378 Analyze_Dimension
(N
);
1379 end Analyze_Object_Renaming
;
1381 ------------------------------
1382 -- Analyze_Package_Renaming --
1383 ------------------------------
1385 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1386 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1391 if Name
(N
) = Error
then
1395 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1397 Check_Text_IO_Special_Unit
(Name
(N
));
1399 if Current_Scope
/= Standard_Standard
then
1400 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1406 if Is_Entity_Name
(Name
(N
)) then
1407 Old_P
:= Entity
(Name
(N
));
1412 if Etype
(Old_P
) = Any_Type
then
1413 Error_Msg_N
("expect package name in renaming", Name
(N
));
1415 elsif Ekind
(Old_P
) /= E_Package
1416 and then not (Ekind
(Old_P
) = E_Generic_Package
1417 and then In_Open_Scopes
(Old_P
))
1419 if Ekind
(Old_P
) = E_Generic_Package
then
1421 ("generic package cannot be renamed as a package", Name
(N
));
1423 Error_Msg_Sloc
:= Sloc
(Old_P
);
1425 ("expect package name in renaming, found& declared#",
1429 -- Set basic attributes to minimize cascaded errors
1431 Set_Ekind
(New_P
, E_Package
);
1432 Set_Etype
(New_P
, Standard_Void_Type
);
1434 -- Here for OK package renaming
1437 -- Entities in the old package are accessible through the renaming
1438 -- entity. The simplest implementation is to have both packages share
1441 Set_Ekind
(New_P
, E_Package
);
1442 Set_Etype
(New_P
, Standard_Void_Type
);
1444 if Present
(Renamed_Object
(Old_P
)) then
1445 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1447 Set_Renamed_Object
(New_P
, Old_P
);
1450 -- The package renaming declaration may become Ghost if it renames a
1453 Mark_Ghost_Renaming
(N
, Old_P
);
1455 Set_Has_Completion
(New_P
);
1456 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1457 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1458 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1459 Check_Library_Unit_Renaming
(N
, Old_P
);
1460 Generate_Reference
(Old_P
, Name
(N
));
1462 -- If the renaming is in the visible part of a package, then we set
1463 -- Renamed_In_Spec for the renamed package, to prevent giving
1464 -- warnings about no entities referenced. Such a warning would be
1465 -- overenthusiastic, since clients can see entities in the renamed
1466 -- package via the visible package renaming.
1469 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1471 if Ekind
(Ent
) = E_Package
1472 and then not In_Private_Part
(Ent
)
1473 and then In_Extended_Main_Source_Unit
(N
)
1474 and then Ekind
(Old_P
) = E_Package
1476 Set_Renamed_In_Spec
(Old_P
);
1480 -- If this is the renaming declaration of a package instantiation
1481 -- within itself, it is the declaration that ends the list of actuals
1482 -- for the instantiation. At this point, the subtypes that rename
1483 -- the actuals are flagged as generic, to avoid spurious ambiguities
1484 -- if the actuals for two distinct formals happen to coincide. If
1485 -- the actual is a private type, the subtype has a private completion
1486 -- that is flagged in the same fashion.
1488 -- Resolution is identical to what is was in the original generic.
1489 -- On exit from the generic instance, these are turned into regular
1490 -- subtypes again, so they are compatible with types in their class.
1492 if not Is_Generic_Instance
(Old_P
) then
1495 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1498 if Nkind
(Spec
) = N_Package_Specification
1499 and then Present
(Generic_Parent
(Spec
))
1500 and then Old_P
= Current_Scope
1501 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1507 E
:= First_Entity
(Old_P
);
1508 while Present
(E
) and then E
/= New_P
loop
1510 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1512 Set_Is_Generic_Actual_Type
(E
);
1514 if Is_Private_Type
(E
)
1515 and then Present
(Full_View
(E
))
1517 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1527 -- Implementation-defined aspect specifications can appear in a renaming
1528 -- declaration, but not language-defined ones. The call to procedure
1529 -- Analyze_Aspect_Specifications will take care of this error check.
1531 if Has_Aspects
(N
) then
1532 Analyze_Aspect_Specifications
(N
, New_P
);
1534 end Analyze_Package_Renaming
;
1536 -------------------------------
1537 -- Analyze_Renamed_Character --
1538 -------------------------------
1540 procedure Analyze_Renamed_Character
1545 C
: constant Node_Id
:= Name
(N
);
1548 if Ekind
(New_S
) = E_Function
then
1549 Resolve
(C
, Etype
(New_S
));
1552 Check_Frozen_Renaming
(N
, New_S
);
1556 Error_Msg_N
("character literal can only be renamed as function", N
);
1558 end Analyze_Renamed_Character
;
1560 ---------------------------------
1561 -- Analyze_Renamed_Dereference --
1562 ---------------------------------
1564 procedure Analyze_Renamed_Dereference
1569 Nam
: constant Node_Id
:= Name
(N
);
1570 P
: constant Node_Id
:= Prefix
(Nam
);
1576 if not Is_Overloaded
(P
) then
1577 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1578 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1580 Error_Msg_N
("designated type does not match specification", P
);
1589 Get_First_Interp
(Nam
, Ind
, It
);
1591 while Present
(It
.Nam
) loop
1593 if Ekind
(It
.Nam
) = E_Subprogram_Type
1594 and then Type_Conformant
(It
.Nam
, New_S
)
1596 if Typ
/= Any_Id
then
1597 Error_Msg_N
("ambiguous renaming", P
);
1604 Get_Next_Interp
(Ind
, It
);
1607 if Typ
= Any_Type
then
1608 Error_Msg_N
("designated type does not match specification", P
);
1613 Check_Frozen_Renaming
(N
, New_S
);
1617 end Analyze_Renamed_Dereference
;
1619 ---------------------------
1620 -- Analyze_Renamed_Entry --
1621 ---------------------------
1623 procedure Analyze_Renamed_Entry
1628 Nam
: constant Node_Id
:= Name
(N
);
1629 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1630 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1634 if Entity
(Sel
) = Any_Id
then
1636 -- Selector is undefined on prefix. Error emitted already
1638 Set_Has_Completion
(New_S
);
1642 -- Otherwise find renamed entity and build body of New_S as a call to it
1644 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1646 if Old_S
= Any_Id
then
1647 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1650 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1651 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1652 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1655 -- Only mode conformance required for a renaming_as_declaration
1657 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1660 Inherit_Renamed_Profile
(New_S
, Old_S
);
1662 -- The prefix can be an arbitrary expression that yields a task or
1663 -- protected object, so it must be resolved.
1665 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1668 Set_Convention
(New_S
, Convention
(Old_S
));
1669 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1671 -- AI05-0225: If the renamed entity is a procedure or entry of a
1672 -- protected object, the target object must be a variable.
1674 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1675 and then Ekind
(New_S
) = E_Procedure
1676 and then not Is_Variable
(Prefix
(Nam
))
1680 ("target object of protected operation used as actual for "
1681 & "formal procedure must be a variable", Nam
);
1684 ("target object of protected operation renamed as procedure, "
1685 & "must be a variable", Nam
);
1690 Check_Frozen_Renaming
(N
, New_S
);
1692 end Analyze_Renamed_Entry
;
1694 -----------------------------------
1695 -- Analyze_Renamed_Family_Member --
1696 -----------------------------------
1698 procedure Analyze_Renamed_Family_Member
1703 Nam
: constant Node_Id
:= Name
(N
);
1704 P
: constant Node_Id
:= Prefix
(Nam
);
1708 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1709 or else (Nkind
(P
) = N_Selected_Component
1710 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1712 if Is_Entity_Name
(P
) then
1713 Old_S
:= Entity
(P
);
1715 Old_S
:= Entity
(Selector_Name
(P
));
1718 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1719 Error_Msg_N
("entry family does not match specification", N
);
1722 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1723 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1724 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1728 Error_Msg_N
("no entry family matches specification", N
);
1731 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1734 Check_Frozen_Renaming
(N
, New_S
);
1736 end Analyze_Renamed_Family_Member
;
1738 -----------------------------------------
1739 -- Analyze_Renamed_Primitive_Operation --
1740 -----------------------------------------
1742 procedure Analyze_Renamed_Primitive_Operation
1751 Ctyp
: Conformance_Type
) return Boolean;
1752 -- Verify that the signatures of the renamed entity and the new entity
1753 -- match. The first formal of the renamed entity is skipped because it
1754 -- is the target object in any subsequent call.
1762 Ctyp
: Conformance_Type
) return Boolean
1768 if Ekind
(Subp
) /= Ekind
(New_S
) then
1772 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1773 New_F
:= First_Formal
(New_S
);
1774 while Present
(Old_F
) and then Present
(New_F
) loop
1775 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1779 if Ctyp
>= Mode_Conformant
1780 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1785 Next_Formal
(New_F
);
1786 Next_Formal
(Old_F
);
1792 -- Start of processing for Analyze_Renamed_Primitive_Operation
1795 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1796 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1798 if not Conforms
(Old_S
, Type_Conformant
) then
1803 -- Find the operation that matches the given signature
1811 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1813 while Present
(It
.Nam
) loop
1814 if Conforms
(It
.Nam
, Type_Conformant
) then
1818 Get_Next_Interp
(Ind
, It
);
1823 if Old_S
= Any_Id
then
1824 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1828 if not Conforms
(Old_S
, Subtype_Conformant
) then
1829 Error_Msg_N
("subtype conformance error in renaming", N
);
1832 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1833 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1836 -- Only mode conformance required for a renaming_as_declaration
1838 if not Conforms
(Old_S
, Mode_Conformant
) then
1839 Error_Msg_N
("mode conformance error in renaming", N
);
1842 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1843 -- view of a subprogram is intrinsic, because the compiler has
1844 -- to generate a wrapper for any call to it. If the name in a
1845 -- subprogram renaming is a prefixed view, the entity is thus
1846 -- intrinsic, and 'Access cannot be applied to it.
1848 Set_Convention
(New_S
, Convention_Intrinsic
);
1851 -- Inherit_Renamed_Profile (New_S, Old_S);
1853 -- The prefix can be an arbitrary expression that yields an
1854 -- object, so it must be resolved.
1856 Resolve
(Prefix
(Name
(N
)));
1858 end Analyze_Renamed_Primitive_Operation
;
1860 ---------------------------------
1861 -- Analyze_Subprogram_Renaming --
1862 ---------------------------------
1864 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1865 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1866 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1867 Nam
: constant Node_Id
:= Name
(N
);
1868 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1869 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1870 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1871 Spec
: constant Node_Id
:= Specification
(N
);
1873 Old_S
: Entity_Id
:= Empty
;
1874 Rename_Spec
: Entity_Id
;
1876 procedure Build_Class_Wide_Wrapper
1877 (Ren_Id
: out Entity_Id
;
1878 Wrap_Id
: out Entity_Id
);
1879 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1880 -- type with unknown discriminants and a generic primitive operation of
1881 -- the said type with a box require special processing when the actual
1882 -- is a class-wide type:
1885 -- type Formal_Typ (<>) is private;
1886 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1887 -- package Gen is ...
1889 -- package Inst is new Gen (Actual_Typ'Class);
1891 -- In this case the general renaming mechanism used in the prologue of
1892 -- an instance no longer applies:
1894 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1896 -- The above is replaced the following wrapper/renaming combination:
1898 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1900 -- Prim_Op (Param); -- primitive
1903 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1905 -- This transformation applies only if there is no explicit visible
1906 -- class-wide operation at the point of the instantiation. Ren_Id is
1907 -- the entity of the renaming declaration. When the transformation
1908 -- applies, Wrap_Id is the entity of the generated class-wide wrapper
1909 -- (or Any_Id). Otherwise, Wrap_Id is the entity of the class-wide
1912 procedure Check_Null_Exclusion
1915 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1916 -- following AI rules:
1918 -- If Ren is a renaming of a formal subprogram and one of its
1919 -- parameters has a null exclusion, then the corresponding formal
1920 -- in Sub must also have one. Otherwise the subtype of the Sub's
1921 -- formal parameter must exclude null.
1923 -- If Ren is a renaming of a formal function and its return
1924 -- profile has a null exclusion, then Sub's return profile must
1925 -- have one. Otherwise the subtype of Sub's return profile must
1928 procedure Check_SPARK_Primitive_Operation
(Subp_Id
: Entity_Id
);
1929 -- Ensure that a SPARK renaming denoted by its entity Subp_Id does not
1930 -- declare a primitive operation of a tagged type (SPARK RM 6.1.1(3)).
1932 procedure Freeze_Actual_Profile
;
1933 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1934 -- types: a callable entity freezes its profile, unless it has an
1935 -- incomplete untagged formal (RM 13.14(10.2/3)).
1937 function Has_Class_Wide_Actual
return Boolean;
1938 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1939 -- defaulted formal subprogram where the actual for the controlling
1940 -- formal type is class-wide.
1942 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1943 -- Find renamed entity when the declaration is a renaming_as_body and
1944 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1945 -- rule that a renaming_as_body is illegal if the declaration occurs
1946 -- before the subprogram it completes is frozen, and renaming indirectly
1947 -- renames the subprogram itself.(Defect Report 8652/0027).
1949 ------------------------------
1950 -- Build_Class_Wide_Wrapper --
1951 ------------------------------
1953 procedure Build_Class_Wide_Wrapper
1954 (Ren_Id
: out Entity_Id
;
1955 Wrap_Id
: out Entity_Id
)
1957 Loc
: constant Source_Ptr
:= Sloc
(N
);
1960 (Subp_Id
: Entity_Id
;
1961 Params
: List_Id
) return Node_Id
;
1962 -- Create a dispatching call to invoke routine Subp_Id with actuals
1963 -- built from the parameter specifications of list Params.
1965 function Build_Expr_Fun_Call
1966 (Subp_Id
: Entity_Id
;
1967 Params
: List_Id
) return Node_Id
;
1968 -- Create a dispatching call to invoke function Subp_Id with actuals
1969 -- built from the parameter specifications of list Params. Return
1970 -- directly the call, so that it can be used inside an expression
1971 -- function. This is a specificity of the GNATprove mode.
1973 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1974 -- Create a subprogram specification based on the subprogram profile
1977 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1978 -- Find a primitive subprogram of type Typ which matches the profile
1979 -- of the renaming declaration.
1981 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
1982 -- Emit a continuation error message suggesting subprogram Subp_Id as
1983 -- a possible interpretation.
1985 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
1986 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
1989 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
1990 -- Determine whether subprogram Subp_Id is a suitable candidate for
1991 -- the role of a wrapped subprogram.
1998 (Subp_Id
: Entity_Id
;
1999 Params
: List_Id
) return Node_Id
2001 Actuals
: constant List_Id
:= New_List
;
2002 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
2006 -- Build the actual parameters of the call
2008 Formal
:= First
(Params
);
2009 while Present
(Formal
) loop
2011 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2016 -- return Subp_Id (Actuals);
2018 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2020 Make_Simple_Return_Statement
(Loc
,
2022 Make_Function_Call
(Loc
,
2024 Parameter_Associations
=> Actuals
));
2027 -- Subp_Id (Actuals);
2031 Make_Procedure_Call_Statement
(Loc
,
2033 Parameter_Associations
=> Actuals
);
2037 -------------------------
2038 -- Build_Expr_Fun_Call --
2039 -------------------------
2041 function Build_Expr_Fun_Call
2042 (Subp_Id
: Entity_Id
;
2043 Params
: List_Id
) return Node_Id
2045 Actuals
: constant List_Id
:= New_List
;
2046 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
2050 pragma Assert
(Ekind_In
(Subp_Id
, E_Function
, E_Operator
));
2052 -- Build the actual parameters of the call
2054 Formal
:= First
(Params
);
2055 while Present
(Formal
) loop
2057 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
2062 -- Subp_Id (Actuals);
2065 Make_Function_Call
(Loc
,
2067 Parameter_Associations
=> Actuals
);
2068 end Build_Expr_Fun_Call
;
2074 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2075 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2076 Spec_Id
: constant Entity_Id
:=
2077 Make_Defining_Identifier
(Loc
,
2078 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2081 if Ekind
(Formal_Spec
) = E_Procedure
then
2083 Make_Procedure_Specification
(Loc
,
2084 Defining_Unit_Name
=> Spec_Id
,
2085 Parameter_Specifications
=> Params
);
2088 Make_Function_Specification
(Loc
,
2089 Defining_Unit_Name
=> Spec_Id
,
2090 Parameter_Specifications
=> Params
,
2091 Result_Definition
=>
2092 New_Copy_Tree
(Result_Definition
(Spec
)));
2096 --------------------
2097 -- Find_Primitive --
2098 --------------------
2100 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2101 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2102 -- Given a specification Spec, replace all class-wide parameter
2103 -- types with reference to type Typ.
2105 -----------------------------
2106 -- Replace_Parameter_Types --
2107 -----------------------------
2109 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2111 Formal_Id
: Entity_Id
;
2112 Formal_Typ
: Node_Id
;
2115 Formal
:= First
(Parameter_Specifications
(Spec
));
2116 while Present
(Formal
) loop
2117 Formal_Id
:= Defining_Identifier
(Formal
);
2118 Formal_Typ
:= Parameter_Type
(Formal
);
2120 -- Create a new entity for each class-wide formal to prevent
2121 -- aliasing with the original renaming. Replace the type of
2122 -- such a parameter with the candidate type.
2124 if Nkind
(Formal_Typ
) = N_Identifier
2125 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2127 Set_Defining_Identifier
(Formal
,
2128 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2130 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2135 end Replace_Parameter_Types
;
2139 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2140 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2141 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2142 Subp_Id
: Entity_Id
;
2144 -- Start of processing for Find_Primitive
2147 -- Each attempt to find a suitable primitive of a particular type
2148 -- operates on its own copy of the original renaming. As a result
2149 -- the original renaming is kept decoration and side-effect free.
2151 -- Inherit the overloaded status of the renamed subprogram name
2153 if Is_Overloaded
(Nam
) then
2154 Set_Is_Overloaded
(Alt_Nam
);
2155 Save_Interps
(Nam
, Alt_Nam
);
2158 -- The copied renaming is hidden from visibility to prevent the
2159 -- pollution of the enclosing context.
2161 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2163 -- The types of all class-wide parameters must be changed to the
2166 Replace_Parameter_Types
(Alt_Spec
);
2168 -- Try to find a suitable primitive which matches the altered
2169 -- profile of the renaming specification.
2174 Nam
=> Name
(Alt_Ren
),
2175 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2176 Is_Actual
=> Is_Actual
);
2178 -- Do not return Any_Id if the resolion of the altered profile
2179 -- failed as this complicates further checks on the caller side,
2180 -- return Empty instead.
2182 if Subp_Id
= Any_Id
then
2189 --------------------------
2190 -- Interpretation_Error --
2191 --------------------------
2193 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2195 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2197 if Is_Internal
(Subp_Id
) then
2199 ("\\possible interpretation: predefined & #",
2203 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2205 end Interpretation_Error
;
2207 ---------------------------
2208 -- Is_Intrinsic_Equality --
2209 ---------------------------
2211 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2214 Ekind
(Subp_Id
) = E_Operator
2215 and then Chars
(Subp_Id
) = Name_Op_Eq
2216 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2217 end Is_Intrinsic_Equality
;
2219 ---------------------------
2220 -- Is_Suitable_Candidate --
2221 ---------------------------
2223 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2225 if No
(Subp_Id
) then
2228 -- An intrinsic subprogram is never a good candidate. This is an
2229 -- indication of a missing primitive, either defined directly or
2230 -- inherited from a parent tagged type.
2232 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2238 end Is_Suitable_Candidate
;
2242 Actual_Typ
: Entity_Id
:= Empty
;
2243 -- The actual class-wide type for Formal_Typ
2245 CW_Prim_OK
: Boolean;
2246 CW_Prim_Op
: Entity_Id
;
2247 -- The class-wide subprogram (if available) which corresponds to the
2248 -- renamed generic formal subprogram.
2250 Formal_Typ
: Entity_Id
:= Empty
;
2251 -- The generic formal type with unknown discriminants
2253 Root_Prim_OK
: Boolean;
2254 Root_Prim_Op
: Entity_Id
;
2255 -- The root type primitive (if available) which corresponds to the
2256 -- renamed generic formal subprogram.
2258 Root_Typ
: Entity_Id
:= Empty
;
2259 -- The root type of Actual_Typ
2261 Body_Decl
: Node_Id
;
2263 Prim_Op
: Entity_Id
;
2264 Spec_Decl
: Node_Id
;
2267 -- Start of processing for Build_Class_Wide_Wrapper
2270 -- Analyze the specification of the renaming in case the generation
2271 -- of the class-wide wrapper fails.
2273 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2276 -- Do not attempt to build a wrapper if the renaming is in error
2278 if Error_Posted
(Nam
) then
2282 -- Analyze the renamed name, but do not resolve it. The resolution is
2283 -- completed once a suitable subprogram is found.
2287 -- When the renamed name denotes the intrinsic operator equals, the
2288 -- name must be treated as overloaded. This allows for a potential
2289 -- match against the root type's predefined equality function.
2291 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2292 Set_Is_Overloaded
(Nam
);
2293 Collect_Interps
(Nam
);
2296 -- Step 1: Find the generic formal type with unknown discriminants
2297 -- and its corresponding class-wide actual type from the renamed
2298 -- generic formal subprogram.
2300 Formal
:= First_Formal
(Formal_Spec
);
2301 while Present
(Formal
) loop
2302 if Has_Unknown_Discriminants
(Etype
(Formal
))
2303 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2304 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2306 Formal_Typ
:= Etype
(Formal
);
2307 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2308 Root_Typ
:= Etype
(Actual_Typ
);
2312 Next_Formal
(Formal
);
2315 -- The specification of the generic formal subprogram should always
2316 -- contain a formal type with unknown discriminants whose actual is
2317 -- a class-wide type, otherwise this indicates a failure in routine
2318 -- Has_Class_Wide_Actual.
2320 pragma Assert
(Present
(Formal_Typ
));
2322 -- Step 2: Find the proper class-wide subprogram or primitive which
2323 -- corresponds to the renamed generic formal subprogram.
2325 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2326 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2327 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2328 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2330 -- The class-wide actual type has two subprograms which correspond to
2331 -- the renamed generic formal subprogram:
2333 -- with procedure Prim_Op (Param : Formal_Typ);
2335 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2336 -- procedure Prim_Op (Param : Actual_Typ'Class);
2338 -- Even though the declaration of the two subprograms is legal, a
2339 -- call to either one is ambiguous and therefore illegal.
2341 if CW_Prim_OK
and Root_Prim_OK
then
2343 -- A user-defined primitive has precedence over a predefined one
2345 if Is_Internal
(CW_Prim_Op
)
2346 and then not Is_Internal
(Root_Prim_Op
)
2348 Prim_Op
:= Root_Prim_Op
;
2350 elsif Is_Internal
(Root_Prim_Op
)
2351 and then not Is_Internal
(CW_Prim_Op
)
2353 Prim_Op
:= CW_Prim_Op
;
2355 elsif CW_Prim_Op
= Root_Prim_Op
then
2356 Prim_Op
:= Root_Prim_Op
;
2358 -- Otherwise both candidate subprograms are user-defined and
2363 ("ambiguous actual for generic subprogram &",
2365 Interpretation_Error
(Root_Prim_Op
);
2366 Interpretation_Error
(CW_Prim_Op
);
2370 elsif CW_Prim_OK
and not Root_Prim_OK
then
2371 Prim_Op
:= CW_Prim_Op
;
2373 elsif not CW_Prim_OK
and Root_Prim_OK
then
2374 Prim_Op
:= Root_Prim_Op
;
2376 -- An intrinsic equality may act as a suitable candidate in the case
2377 -- of a null type extension where the parent's equality is hidden. A
2378 -- call to an intrinsic equality is expanded as dispatching.
2380 elsif Present
(Root_Prim_Op
)
2381 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2383 Prim_Op
:= Root_Prim_Op
;
2385 -- Otherwise there are no candidate subprograms. Let the caller
2386 -- diagnose the error.
2392 -- At this point resolution has taken place and the name is no longer
2393 -- overloaded. Mark the primitive as referenced.
2395 Set_Is_Overloaded
(Name
(N
), False);
2396 Set_Referenced
(Prim_Op
);
2398 -- Do not generate a wrapper when the only candidate is a class-wide
2399 -- subprogram. Instead modify the renaming to directly map the actual
2400 -- to the generic formal.
2402 if CW_Prim_OK
and then Prim_Op
= CW_Prim_Op
then
2404 Rewrite
(Nam
, New_Occurrence_Of
(Prim_Op
, Loc
));
2408 -- Step 3: Create the declaration and the body of the wrapper, insert
2409 -- all the pieces into the tree.
2411 -- In GNATprove mode, create a function wrapper in the form of an
2412 -- expression function, so that an implicit postcondition relating
2413 -- the result of calling the wrapper function and the result of the
2414 -- dispatching call to the wrapped function is known during proof.
2417 and then Ekind_In
(Ren_Id
, E_Function
, E_Operator
)
2419 New_Spec
:= Build_Spec
(Ren_Id
);
2421 Make_Expression_Function
(Loc
,
2422 Specification
=> New_Spec
,
2425 (Subp_Id
=> Prim_Op
,
2426 Params
=> Parameter_Specifications
(New_Spec
)));
2428 Wrap_Id
:= Defining_Entity
(Body_Decl
);
2430 -- Otherwise, create separate spec and body for the subprogram
2434 Make_Subprogram_Declaration
(Loc
,
2435 Specification
=> Build_Spec
(Ren_Id
));
2436 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2438 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2441 Make_Subprogram_Body
(Loc
,
2442 Specification
=> Build_Spec
(Ren_Id
),
2443 Declarations
=> New_List
,
2444 Handled_Statement_Sequence
=>
2445 Make_Handled_Sequence_Of_Statements
(Loc
,
2446 Statements
=> New_List
(
2448 (Subp_Id
=> Prim_Op
,
2450 Parameter_Specifications
2451 (Specification
(Spec_Decl
))))));
2453 Set_Corresponding_Body
(Spec_Decl
, Defining_Entity
(Body_Decl
));
2456 -- If the operator carries an Eliminated pragma, indicate that the
2457 -- wrapper is also to be eliminated, to prevent spurious error when
2458 -- using gnatelim on programs that include box-initialization of
2459 -- equality operators.
2461 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2463 -- In GNATprove mode, insert the body in the tree for analysis
2465 if GNATprove_Mode
then
2466 Insert_Before_And_Analyze
(N
, Body_Decl
);
2469 -- The generated body does not freeze and must be analyzed when the
2470 -- class-wide wrapper is frozen. The body is only needed if expansion
2473 if Expander_Active
then
2474 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2477 -- Step 4: The subprogram renaming aliases the wrapper
2479 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2480 end Build_Class_Wide_Wrapper
;
2482 --------------------------
2483 -- Check_Null_Exclusion --
2484 --------------------------
2486 procedure Check_Null_Exclusion
2490 Ren_Formal
: Entity_Id
;
2491 Sub_Formal
: Entity_Id
;
2496 Ren_Formal
:= First_Formal
(Ren
);
2497 Sub_Formal
:= First_Formal
(Sub
);
2498 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2499 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2501 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2502 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2505 ("`NOT NULL` required for parameter &",
2506 Parent
(Sub_Formal
), Sub_Formal
);
2509 Next_Formal
(Ren_Formal
);
2510 Next_Formal
(Sub_Formal
);
2513 -- Return profile check
2515 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2516 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2517 and then Has_Null_Exclusion
(Parent
(Ren
))
2518 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2519 or else Can_Never_Be_Null
(Etype
(Sub
)))
2522 ("return must specify `NOT NULL`",
2523 Result_Definition
(Parent
(Sub
)));
2525 end Check_Null_Exclusion
;
2527 -------------------------------------
2528 -- Check_SPARK_Primitive_Operation --
2529 -------------------------------------
2531 procedure Check_SPARK_Primitive_Operation
(Subp_Id
: Entity_Id
) is
2532 Prag
: constant Node_Id
:= SPARK_Pragma
(Subp_Id
);
2536 -- Nothing to do when the subprogram is not subject to SPARK_Mode On
2537 -- because this check applies to SPARK code only.
2539 if not (Present
(Prag
)
2540 and then Get_SPARK_Mode_From_Annotation
(Prag
) = On
)
2544 -- Nothing to do when the subprogram is not a primitive operation
2546 elsif not Is_Primitive
(Subp_Id
) then
2550 Typ
:= Find_Dispatching_Type
(Subp_Id
);
2552 -- Nothing to do when the subprogram is a primitive operation of an
2559 -- At this point a renaming declaration introduces a new primitive
2560 -- operation for a tagged type.
2562 Error_Msg_Node_2
:= Typ
;
2564 ("subprogram renaming & cannot declare primitive for type & "
2565 & "(SPARK RM 6.1.1(3))", N
, Subp_Id
);
2566 end Check_SPARK_Primitive_Operation
;
2568 ---------------------------
2569 -- Freeze_Actual_Profile --
2570 ---------------------------
2572 procedure Freeze_Actual_Profile
is
2574 Has_Untagged_Inc
: Boolean;
2575 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2578 if Ada_Version
>= Ada_2012
then
2579 F
:= First_Formal
(Formal_Spec
);
2580 Has_Untagged_Inc
:= False;
2581 while Present
(F
) loop
2582 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2583 and then not Is_Tagged_Type
(Etype
(F
))
2585 Has_Untagged_Inc
:= True;
2589 F
:= Next_Formal
(F
);
2592 if Ekind
(Formal_Spec
) = E_Function
2593 and then not Is_Tagged_Type
(Etype
(Formal_Spec
))
2595 Has_Untagged_Inc
:= True;
2598 if not Has_Untagged_Inc
then
2599 F
:= First_Formal
(Old_S
);
2600 while Present
(F
) loop
2601 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2603 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2604 and then No
(Underlying_Type
(Etype
(F
)))
2606 -- Exclude generic types, or types derived from them.
2607 -- They will be frozen in the enclosing instance.
2609 if Is_Generic_Type
(Etype
(F
))
2610 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2614 -- A limited view of a type declared elsewhere needs no
2615 -- freezing actions.
2617 elsif From_Limited_With
(Etype
(F
)) then
2622 ("type& must be frozen before this point",
2623 Instantiation_Node
, Etype
(F
));
2627 F
:= Next_Formal
(F
);
2631 end Freeze_Actual_Profile
;
2633 ---------------------------
2634 -- Has_Class_Wide_Actual --
2635 ---------------------------
2637 function Has_Class_Wide_Actual
return Boolean is
2639 Formal_Typ
: Entity_Id
;
2643 Formal
:= First_Formal
(Formal_Spec
);
2644 while Present
(Formal
) loop
2645 Formal_Typ
:= Etype
(Formal
);
2647 if Has_Unknown_Discriminants
(Formal_Typ
)
2648 and then not Is_Class_Wide_Type
(Formal_Typ
)
2649 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2654 Next_Formal
(Formal
);
2659 end Has_Class_Wide_Actual
;
2661 -------------------------
2662 -- Original_Subprogram --
2663 -------------------------
2665 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2666 Orig_Decl
: Node_Id
;
2667 Orig_Subp
: Entity_Id
;
2670 -- First case: renamed entity is itself a renaming
2672 if Present
(Alias
(Subp
)) then
2673 return Alias
(Subp
);
2675 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2676 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2678 -- Check if renamed entity is a renaming_as_body
2681 Unit_Declaration_Node
2682 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2684 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2685 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2687 if Orig_Subp
= Rename_Spec
then
2689 -- Circularity detected
2694 return (Original_Subprogram
(Orig_Subp
));
2702 end Original_Subprogram
;
2706 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2707 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2708 -- defaulted formal subprogram when the actual for a related formal
2709 -- type is class-wide.
2711 Inst_Node
: Node_Id
:= Empty
;
2714 -- Start of processing for Analyze_Subprogram_Renaming
2717 -- We must test for the attribute renaming case before the Analyze
2718 -- call because otherwise Sem_Attr will complain that the attribute
2719 -- is missing an argument when it is analyzed.
2721 if Nkind
(Nam
) = N_Attribute_Reference
then
2723 -- In the case of an abstract formal subprogram association, rewrite
2724 -- an actual given by a stream attribute as the name of the
2725 -- corresponding stream primitive of the type.
2727 -- In a generic context the stream operations are not generated, and
2728 -- this must be treated as a normal attribute reference, to be
2729 -- expanded in subsequent instantiations.
2732 and then Is_Abstract_Subprogram
(Formal_Spec
)
2733 and then Expander_Active
2736 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2737 Stream_Prim
: Entity_Id
;
2740 -- The class-wide forms of the stream attributes are not
2741 -- primitive dispatching operations (even though they
2742 -- internally dispatch to a stream attribute).
2744 if Is_Class_Wide_Type
(Prefix_Type
) then
2746 ("attribute must be a primitive dispatching operation",
2751 -- Retrieve the primitive subprogram associated with the
2752 -- attribute. This can only be a stream attribute, since those
2753 -- are the only ones that are dispatching (and the actual for
2754 -- an abstract formal subprogram must be dispatching
2757 case Attribute_Name
(Nam
) is
2760 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2764 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2768 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2772 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2776 ("attribute must be a primitive dispatching operation",
2781 -- If no operation was found, and the type is limited, the user
2782 -- should have defined one.
2784 if No
(Stream_Prim
) then
2785 if Is_Limited_Type
(Prefix_Type
) then
2787 ("stream operation not defined for type&",
2791 -- Otherwise, compiler should have generated default
2794 raise Program_Error
;
2798 -- Rewrite the attribute into the name of its corresponding
2799 -- primitive dispatching subprogram. We can then proceed with
2800 -- the usual processing for subprogram renamings.
2803 Prim_Name
: constant Node_Id
:=
2804 Make_Identifier
(Sloc
(Nam
),
2805 Chars
=> Chars
(Stream_Prim
));
2807 Set_Entity
(Prim_Name
, Stream_Prim
);
2808 Rewrite
(Nam
, Prim_Name
);
2813 -- Normal processing for a renaming of an attribute
2816 Attribute_Renaming
(N
);
2821 -- Check whether this declaration corresponds to the instantiation of a
2822 -- formal subprogram.
2824 -- If this is an instantiation, the corresponding actual is frozen and
2825 -- error messages can be made more precise. If this is a default
2826 -- subprogram, the entity is already established in the generic, and is
2827 -- not retrieved by visibility. If it is a default with a box, the
2828 -- candidate interpretations, if any, have been collected when building
2829 -- the renaming declaration. If overloaded, the proper interpretation is
2830 -- determined in Find_Renamed_Entity. If the entity is an operator,
2831 -- Find_Renamed_Entity applies additional visibility checks.
2834 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2836 -- Check whether the renaming is for a defaulted actual subprogram
2837 -- with a class-wide actual.
2839 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2840 -- is an external axiomatization on the package.
2843 and then Box_Present
(Inst_Node
)
2847 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2849 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2851 elsif Is_Entity_Name
(Nam
)
2852 and then Present
(Entity
(Nam
))
2853 and then not Comes_From_Source
(Nam
)
2854 and then not Is_Overloaded
(Nam
)
2856 Old_S
:= Entity
(Nam
);
2858 -- The subprogram renaming declaration may become Ghost if it
2859 -- renames a Ghost entity.
2861 Mark_Ghost_Renaming
(N
, Old_S
);
2863 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2867 if Ekind
(Old_S
) = E_Operator
then
2871 if Box_Present
(Inst_Node
) then
2872 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2874 -- If there is an immediately visible homonym of the operator
2875 -- and the declaration has a default, this is worth a warning
2876 -- because the user probably did not intend to get the pre-
2877 -- defined operator, visible in the generic declaration. To
2878 -- find if there is an intended candidate, analyze the renaming
2879 -- again in the current context.
2881 elsif Scope
(Old_S
) = Standard_Standard
2882 and then Present
(Default_Name
(Inst_Node
))
2885 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2889 Set_Entity
(Name
(Decl
), Empty
);
2890 Analyze
(Name
(Decl
));
2892 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2895 and then In_Open_Scopes
(Scope
(Hidden
))
2896 and then Is_Immediately_Visible
(Hidden
)
2897 and then Comes_From_Source
(Hidden
)
2898 and then Hidden
/= Old_S
2900 Error_Msg_Sloc
:= Sloc
(Hidden
);
2902 ("default subprogram is resolved in the generic "
2903 & "declaration (RM 12.6(17))??", N
);
2904 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2913 -- The subprogram renaming declaration may become Ghost if it
2914 -- renames a Ghost entity.
2916 if Is_Entity_Name
(Nam
) then
2917 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
2920 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2924 -- Renamed entity must be analyzed first, to avoid being hidden by
2925 -- new name (which might be the same in a generic instance).
2929 -- The subprogram renaming declaration may become Ghost if it renames
2932 if Is_Entity_Name
(Nam
) then
2933 Mark_Ghost_Renaming
(N
, Entity
(Nam
));
2936 -- The renaming defines a new overloaded entity, which is analyzed
2937 -- like a subprogram declaration.
2939 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2942 if Current_Scope
/= Standard_Standard
then
2943 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2946 -- Set SPARK mode from current context
2948 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2949 Set_SPARK_Pragma_Inherited
(New_S
);
2951 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2953 -- Case of Renaming_As_Body
2955 if Present
(Rename_Spec
) then
2956 Check_Previous_Null_Procedure
(N
, Rename_Spec
);
2958 -- Renaming declaration is the completion of the declaration of
2959 -- Rename_Spec. We build an actual body for it at the freezing point.
2961 Set_Corresponding_Spec
(N
, Rename_Spec
);
2963 -- Deal with special case of stream functions of abstract types
2966 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2967 N_Abstract_Subprogram_Declaration
2969 -- Input stream functions are abstract if the object type is
2970 -- abstract. Similarly, all default stream functions for an
2971 -- interface type are abstract. However, these subprograms may
2972 -- receive explicit declarations in representation clauses, making
2973 -- the attribute subprograms usable as defaults in subsequent
2975 -- In this case we rewrite the declaration to make the subprogram
2976 -- non-abstract. We remove the previous declaration, and insert
2977 -- the new one at the point of the renaming, to prevent premature
2978 -- access to unfrozen types. The new declaration reuses the
2979 -- specification of the previous one, and must not be analyzed.
2982 (Is_Primitive
(Entity
(Nam
))
2984 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2986 Old_Decl
: constant Node_Id
:=
2987 Unit_Declaration_Node
(Rename_Spec
);
2988 New_Decl
: constant Node_Id
:=
2989 Make_Subprogram_Declaration
(Sloc
(N
),
2991 Relocate_Node
(Specification
(Old_Decl
)));
2994 Insert_After
(N
, New_Decl
);
2995 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2996 Set_Analyzed
(New_Decl
);
3000 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
3002 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
3003 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
3006 Set_Convention
(New_S
, Convention
(Rename_Spec
));
3007 Check_Fully_Conformant
(New_S
, Rename_Spec
);
3008 Set_Public_Status
(New_S
);
3010 if No_Return
(Rename_Spec
)
3011 and then not No_Return
(Entity
(Nam
))
3013 Error_Msg_N
("renaming completes a No_Return procedure", N
);
3015 ("\renamed procedure must be nonreturning (RM 6.5.1 (7/2))", N
);
3018 -- The specification does not introduce new formals, but only
3019 -- repeats the formals of the original subprogram declaration.
3020 -- For cross-reference purposes, and for refactoring tools, we
3021 -- treat the formals of the renaming declaration as body formals.
3023 Reference_Body_Formals
(Rename_Spec
, New_S
);
3025 -- Indicate that the entity in the declaration functions like the
3026 -- corresponding body, and is not a new entity. The body will be
3027 -- constructed later at the freeze point, so indicate that the
3028 -- completion has not been seen yet.
3030 Set_Ekind
(New_S
, E_Subprogram_Body
);
3031 New_S
:= Rename_Spec
;
3032 Set_Has_Completion
(Rename_Spec
, False);
3034 -- Ada 2005: check overriding indicator
3036 if Present
(Overridden_Operation
(Rename_Spec
)) then
3037 if Must_Not_Override
(Specification
(N
)) then
3039 ("subprogram& overrides inherited operation",
3043 and then not Must_Override
(Specification
(N
))
3045 Style
.Missing_Overriding
(N
, Rename_Spec
);
3048 elsif Must_Override
(Specification
(N
)) then
3049 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
3052 -- Normal subprogram renaming (not renaming as body)
3055 Generate_Definition
(New_S
);
3056 New_Overloaded_Entity
(New_S
);
3058 if not (Is_Entity_Name
(Nam
)
3059 and then Is_Intrinsic_Subprogram
(Entity
(Nam
)))
3061 Check_Delayed_Subprogram
(New_S
);
3064 -- Verify that a SPARK renaming does not declare a primitive
3065 -- operation of a tagged type.
3067 Check_SPARK_Primitive_Operation
(New_S
);
3070 -- There is no need for elaboration checks on the new entity, which may
3071 -- be called before the next freezing point where the body will appear.
3072 -- Elaboration checks refer to the real entity, not the one created by
3073 -- the renaming declaration.
3075 Set_Kill_Elaboration_Checks
(New_S
, True);
3077 -- If we had a previous error, indicate a completely is present to stop
3078 -- junk cascaded messages, but don't take any further action.
3080 if Etype
(Nam
) = Any_Type
then
3081 Set_Has_Completion
(New_S
);
3084 -- Case where name has the form of a selected component
3086 elsif Nkind
(Nam
) = N_Selected_Component
then
3088 -- A name which has the form A.B can designate an entry of task A, a
3089 -- protected operation of protected object A, or finally a primitive
3090 -- operation of object A. In the later case, A is an object of some
3091 -- tagged type, or an access type that denotes one such. To further
3092 -- distinguish these cases, note that the scope of a task entry or
3093 -- protected operation is type of the prefix.
3095 -- The prefix could be an overloaded function call that returns both
3096 -- kinds of operations. This overloading pathology is left to the
3097 -- dedicated reader ???
3100 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
3108 and then Is_Tagged_Type
(Designated_Type
(T
))))
3109 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
3111 Analyze_Renamed_Primitive_Operation
3112 (N
, New_S
, Present
(Rename_Spec
));
3116 -- Renamed entity is an entry or protected operation. For those
3117 -- cases an explicit body is built (at the point of freezing of
3118 -- this entity) that contains a call to the renamed entity.
3120 -- This is not allowed for renaming as body if the renamed
3121 -- spec is already frozen (see RM 8.5.4(5) for details).
3123 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
3125 ("renaming-as-body cannot rename entry as subprogram", N
);
3127 ("\since & is already frozen (RM 8.5.4(5))",
3130 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
3137 -- Case where name is an explicit dereference X.all
3139 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
3141 -- Renamed entity is designated by access_to_subprogram expression.
3142 -- Must build body to encapsulate call, as in the entry case.
3144 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
3147 -- Indexed component
3149 elsif Nkind
(Nam
) = N_Indexed_Component
then
3150 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
3153 -- Character literal
3155 elsif Nkind
(Nam
) = N_Character_Literal
then
3156 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
3159 -- Only remaining case is where we have a non-entity name, or a renaming
3160 -- of some other non-overloadable entity.
3162 elsif not Is_Entity_Name
(Nam
)
3163 or else not Is_Overloadable
(Entity
(Nam
))
3165 -- Do not mention the renaming if it comes from an instance
3167 if not Is_Actual
then
3168 Error_Msg_N
("expect valid subprogram name in renaming", N
);
3170 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3176 -- Find the renamed entity that matches the given specification. Disable
3177 -- Ada_83 because there is no requirement of full conformance between
3178 -- renamed entity and new entity, even though the same circuit is used.
3180 -- This is a bit of an odd case, which introduces a really irregular use
3181 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3184 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3185 Ada_Version_Pragma
:= Empty
;
3186 Ada_Version_Explicit
:= Ada_Version
;
3189 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3191 -- The visible operation may be an inherited abstract operation that
3192 -- was overridden in the private part, in which case a call will
3193 -- dispatch to the overriding operation. Use the overriding one in
3194 -- the renaming declaration, to prevent spurious errors below.
3196 if Is_Overloadable
(Old_S
)
3197 and then Is_Abstract_Subprogram
(Old_S
)
3198 and then No
(DTC_Entity
(Old_S
))
3199 and then Present
(Alias
(Old_S
))
3200 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3201 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3203 Old_S
:= Alias
(Old_S
);
3206 -- When the renamed subprogram is overloaded and used as an actual
3207 -- of a generic, its entity is set to the first available homonym.
3208 -- We must first disambiguate the name, then set the proper entity.
3210 if Is_Actual
and then Is_Overloaded
(Nam
) then
3211 Set_Entity
(Nam
, Old_S
);
3215 -- Most common case: subprogram renames subprogram. No body is generated
3216 -- in this case, so we must indicate the declaration is complete as is.
3217 -- and inherit various attributes of the renamed subprogram.
3219 if No
(Rename_Spec
) then
3220 Set_Has_Completion
(New_S
);
3221 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3222 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3223 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3225 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3226 -- between a subprogram and its correct renaming.
3228 -- Note: the Any_Id check is a guard that prevents compiler crashes
3229 -- when performing a null exclusion check between a renaming and a
3230 -- renamed subprogram that has been found to be illegal.
3232 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3233 Check_Null_Exclusion
3235 Sub
=> Entity
(Nam
));
3238 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3239 -- overriding. The flag Requires_Overriding is set very selectively
3240 -- and misses some other illegal cases. The additional conditions
3241 -- checked below are sufficient but not necessary ???
3243 -- The rule does not apply to the renaming generated for an actual
3244 -- subprogram in an instance.
3249 -- Guard against previous errors, and omit renamings of predefined
3252 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3255 elsif Requires_Overriding
(Old_S
)
3257 (Is_Abstract_Subprogram
(Old_S
)
3258 and then Present
(Find_Dispatching_Type
(Old_S
))
3259 and then not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3262 ("renamed entity cannot be subprogram that requires overriding "
3263 & "(RM 8.5.4 (5.1))", N
);
3267 Prev
: constant Entity_Id
:= Overridden_Operation
(New_S
);
3271 (Has_Non_Trivial_Precondition
(Prev
)
3272 or else Has_Non_Trivial_Precondition
(Old_S
))
3275 ("conflicting inherited classwide preconditions in renaming "
3276 & "of& (RM 6.1.1 (17)", N
, Old_S
);
3281 if Old_S
/= Any_Id
then
3282 if Is_Actual
and then From_Default
(N
) then
3284 -- This is an implicit reference to the default actual
3286 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3289 Generate_Reference
(Old_S
, Nam
);
3292 Check_Internal_Protected_Use
(N
, Old_S
);
3294 -- For a renaming-as-body, require subtype conformance, but if the
3295 -- declaration being completed has not been frozen, then inherit the
3296 -- convention of the renamed subprogram prior to checking conformance
3297 -- (unless the renaming has an explicit convention established; the
3298 -- rule stated in the RM doesn't seem to address this ???).
3300 if Present
(Rename_Spec
) then
3301 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3302 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3304 if not Is_Frozen
(Rename_Spec
) then
3305 if not Has_Convention_Pragma
(Rename_Spec
) then
3306 Set_Convention
(New_S
, Convention
(Old_S
));
3309 if Ekind
(Old_S
) /= E_Operator
then
3310 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3313 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3314 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3317 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3320 Check_Frozen_Renaming
(N
, Rename_Spec
);
3322 -- Check explicitly that renamed entity is not intrinsic, because
3323 -- in a generic the renamed body is not built. In this case,
3324 -- the renaming_as_body is a completion.
3326 if Inside_A_Generic
then
3327 if Is_Frozen
(Rename_Spec
)
3328 and then Is_Intrinsic_Subprogram
(Old_S
)
3331 ("subprogram in renaming_as_body cannot be intrinsic",
3335 Set_Has_Completion
(Rename_Spec
);
3338 elsif Ekind
(Old_S
) /= E_Operator
then
3340 -- If this a defaulted subprogram for a class-wide actual there is
3341 -- no check for mode conformance, given that the signatures don't
3342 -- match (the source mentions T but the actual mentions T'Class).
3346 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3347 Check_Mode_Conformant
(New_S
, Old_S
);
3350 if Is_Actual
and then Error_Posted
(New_S
) then
3351 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3355 if No
(Rename_Spec
) then
3357 -- The parameter profile of the new entity is that of the renamed
3358 -- entity: the subtypes given in the specification are irrelevant.
3360 Inherit_Renamed_Profile
(New_S
, Old_S
);
3362 -- A call to the subprogram is transformed into a call to the
3363 -- renamed entity. This is transitive if the renamed entity is
3364 -- itself a renaming.
3366 if Present
(Alias
(Old_S
)) then
3367 Set_Alias
(New_S
, Alias
(Old_S
));
3369 Set_Alias
(New_S
, Old_S
);
3372 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3373 -- renaming as body, since the entity in this case is not an
3374 -- intrinsic (it calls an intrinsic, but we have a real body for
3375 -- this call, and it is in this body that the required intrinsic
3376 -- processing will take place).
3378 -- Also, if this is a renaming of inequality, the renamed operator
3379 -- is intrinsic, but what matters is the corresponding equality
3380 -- operator, which may be user-defined.
3382 Set_Is_Intrinsic_Subprogram
3384 Is_Intrinsic_Subprogram
(Old_S
)
3386 (Chars
(Old_S
) /= Name_Op_Ne
3387 or else Ekind
(Old_S
) = E_Operator
3388 or else Is_Intrinsic_Subprogram
3389 (Corresponding_Equality
(Old_S
))));
3391 if Ekind
(Alias
(New_S
)) = E_Operator
then
3392 Set_Has_Delayed_Freeze
(New_S
, False);
3395 -- If the renaming corresponds to an association for an abstract
3396 -- formal subprogram, then various attributes must be set to
3397 -- indicate that the renaming is an abstract dispatching operation
3398 -- with a controlling type.
3400 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3402 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3403 -- see it as corresponding to a generic association for a
3404 -- formal abstract subprogram
3406 Set_Is_Abstract_Subprogram
(New_S
);
3409 New_S_Ctrl_Type
: constant Entity_Id
:=
3410 Find_Dispatching_Type
(New_S
);
3411 Old_S_Ctrl_Type
: constant Entity_Id
:=
3412 Find_Dispatching_Type
(Old_S
);
3416 -- The actual must match the (instance of the) formal,
3417 -- and must be a controlling type.
3419 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
3420 or else No
(New_S_Ctrl_Type
)
3423 ("actual must be dispatching subprogram for type&",
3424 Nam
, New_S_Ctrl_Type
);
3427 Set_Is_Dispatching_Operation
(New_S
);
3428 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3430 -- If the actual in the formal subprogram is itself a
3431 -- formal abstract subprogram association, there's no
3432 -- dispatch table component or position to inherit.
3434 if Present
(DTC_Entity
(Old_S
)) then
3435 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3436 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3446 -- The following is illegal, because F hides whatever other F may
3448 -- function F (...) renames F;
3451 or else (Nkind
(Nam
) /= N_Expanded_Name
3452 and then Chars
(Old_S
) = Chars
(New_S
))
3454 Error_Msg_N
("subprogram cannot rename itself", N
);
3456 -- This is illegal even if we use a selector:
3457 -- function F (...) renames Pkg.F;
3458 -- because F is still hidden.
3460 elsif Nkind
(Nam
) = N_Expanded_Name
3461 and then Entity
(Prefix
(Nam
)) = Current_Scope
3462 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3464 -- This is an error, but we overlook the error and accept the
3465 -- renaming if the special Overriding_Renamings mode is in effect.
3467 if not Overriding_Renamings
then
3469 ("implicit operation& is not visible (RM 8.3 (15))",
3474 Set_Convention
(New_S
, Convention
(Old_S
));
3476 if Is_Abstract_Subprogram
(Old_S
) then
3477 if Present
(Rename_Spec
) then
3479 ("a renaming-as-body cannot rename an abstract subprogram",
3481 Set_Has_Completion
(Rename_Spec
);
3483 Set_Is_Abstract_Subprogram
(New_S
);
3487 Check_Library_Unit_Renaming
(N
, Old_S
);
3489 -- Pathological case: procedure renames entry in the scope of its
3490 -- task. Entry is given by simple name, but body must be built for
3491 -- procedure. Of course if called it will deadlock.
3493 if Ekind
(Old_S
) = E_Entry
then
3494 Set_Has_Completion
(New_S
, False);
3495 Set_Alias
(New_S
, Empty
);
3498 -- Do not freeze the renaming nor the renamed entity when the context
3499 -- is an enclosing generic. Freezing is an expansion activity, and in
3500 -- addition the renamed entity may depend on the generic formals of
3501 -- the enclosing generic.
3503 if Is_Actual
and not Inside_A_Generic
then
3504 Freeze_Before
(N
, Old_S
);
3505 Freeze_Actual_Profile
;
3506 Set_Has_Delayed_Freeze
(New_S
, False);
3507 Freeze_Before
(N
, New_S
);
3509 -- An abstract subprogram is only allowed as an actual in the case
3510 -- where the formal subprogram is also abstract.
3512 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3513 and then Is_Abstract_Subprogram
(Old_S
)
3514 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3517 ("abstract subprogram not allowed as generic actual", Nam
);
3522 -- A common error is to assume that implicit operators for types are
3523 -- defined in Standard, or in the scope of a subtype. In those cases
3524 -- where the renamed entity is given with an expanded name, it is
3525 -- worth mentioning that operators for the type are not declared in
3526 -- the scope given by the prefix.
3528 if Nkind
(Nam
) = N_Expanded_Name
3529 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3530 and then Scope
(Entity
(Nam
)) = Standard_Standard
3533 T
: constant Entity_Id
:=
3534 Base_Type
(Etype
(First_Formal
(New_S
)));
3536 Error_Msg_Node_2
:= Prefix
(Nam
);
3538 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3543 ("no visible subprogram matches the specification for&",
3547 if Present
(Candidate_Renaming
) then
3554 F1
:= First_Formal
(Candidate_Renaming
);
3555 F2
:= First_Formal
(New_S
);
3556 T1
:= First_Subtype
(Etype
(F1
));
3557 while Present
(F1
) and then Present
(F2
) loop
3562 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3563 if Present
(Next_Formal
(F1
)) then
3565 ("\missing specification for & and other formals with "
3566 & "defaults", Spec
, F1
);
3568 Error_Msg_NE
("\missing specification for &", Spec
, F1
);
3572 if Nkind
(Nam
) = N_Operator_Symbol
3573 and then From_Default
(N
)
3575 Error_Msg_Node_2
:= T1
;
3577 ("default & on & is not directly visible", Nam
, Nam
);
3583 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3584 -- controlling access parameters are known non-null for the renamed
3585 -- subprogram. Test also applies to a subprogram instantiation that
3586 -- is dispatching. Test is skipped if some previous error was detected
3587 -- that set Old_S to Any_Id.
3589 if Ada_Version
>= Ada_2005
3590 and then Old_S
/= Any_Id
3591 and then not Is_Dispatching_Operation
(Old_S
)
3592 and then Is_Dispatching_Operation
(New_S
)
3599 Old_F
:= First_Formal
(Old_S
);
3600 New_F
:= First_Formal
(New_S
);
3601 while Present
(Old_F
) loop
3602 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3603 and then Is_Controlling_Formal
(New_F
)
3604 and then not Can_Never_Be_Null
(Old_F
)
3606 Error_Msg_N
("access parameter is controlling,", New_F
);
3608 ("\corresponding parameter of& must be explicitly null "
3609 & "excluding", New_F
, Old_S
);
3612 Next_Formal
(Old_F
);
3613 Next_Formal
(New_F
);
3618 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3619 -- is to warn if an operator is being renamed as a different operator.
3620 -- If the operator is predefined, examine the kind of the entity, not
3621 -- the abbreviated declaration in Standard.
3623 if Comes_From_Source
(N
)
3624 and then Present
(Old_S
)
3625 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3626 or else Ekind
(Old_S
) = E_Operator
)
3627 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3628 and then Chars
(Old_S
) /= Chars
(New_S
)
3631 ("& is being renamed as a different operator??", N
, Old_S
);
3634 -- Check for renaming of obsolescent subprogram
3636 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3638 -- Another warning or some utility: if the new subprogram as the same
3639 -- name as the old one, the old one is not hidden by an outer homograph,
3640 -- the new one is not a public symbol, and the old one is otherwise
3641 -- directly visible, the renaming is superfluous.
3643 if Chars
(Old_S
) = Chars
(New_S
)
3644 and then Comes_From_Source
(N
)
3645 and then Scope
(Old_S
) /= Standard_Standard
3646 and then Warn_On_Redundant_Constructs
3647 and then (Is_Immediately_Visible
(Old_S
)
3648 or else Is_Potentially_Use_Visible
(Old_S
))
3649 and then Is_Overloadable
(Current_Scope
)
3650 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3653 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3656 -- Implementation-defined aspect specifications can appear in a renaming
3657 -- declaration, but not language-defined ones. The call to procedure
3658 -- Analyze_Aspect_Specifications will take care of this error check.
3660 if Has_Aspects
(N
) then
3661 Analyze_Aspect_Specifications
(N
, New_S
);
3664 Ada_Version
:= Save_AV
;
3665 Ada_Version_Pragma
:= Save_AVP
;
3666 Ada_Version_Explicit
:= Save_AV_Exp
;
3668 -- In GNATprove mode, the renamings of actual subprograms are replaced
3669 -- with wrapper functions that make it easier to propagate axioms to the
3670 -- points of call within an instance. Wrappers are generated if formal
3671 -- subprogram is subject to axiomatization.
3673 -- The types in the wrapper profiles are obtained from (instances of)
3674 -- the types of the formal subprogram.
3677 and then GNATprove_Mode
3678 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3679 and then not Inside_A_Generic
3681 if Ekind
(Old_S
) = E_Function
then
3682 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3685 elsif Ekind
(Old_S
) = E_Operator
then
3686 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3691 -- Check if we are looking at an Ada 2012 defaulted formal subprogram
3692 -- and mark any use_package_clauses that affect the visibility of the
3693 -- implicit generic actual.
3695 if Is_Generic_Actual_Subprogram
(New_S
)
3696 and then (Is_Intrinsic_Subprogram
(New_S
) or else From_Default
(N
))
3698 Mark_Use_Clauses
(New_S
);
3700 -- Handle overloaded subprograms
3702 if Present
(Alias
(New_S
)) then
3703 Mark_Use_Clauses
(Alias
(New_S
));
3706 end Analyze_Subprogram_Renaming
;
3708 -------------------------
3709 -- Analyze_Use_Package --
3710 -------------------------
3712 -- Resolve the package names in the use clause, and make all the visible
3713 -- entities defined in the package potentially use-visible. If the package
3714 -- is already in use from a previous use clause, its visible entities are
3715 -- already use-visible. In that case, mark the occurrence as a redundant
3716 -- use. If the package is an open scope, i.e. if the use clause occurs
3717 -- within the package itself, ignore it.
3719 procedure Analyze_Use_Package
(N
: Node_Id
; Chain
: Boolean := True) is
3720 procedure Analyze_Package_Name
(Clause
: Node_Id
);
3721 -- Perform analysis on a package name from a use_package_clause
3723 procedure Analyze_Package_Name_List
(Head_Clause
: Node_Id
);
3724 -- Similar to Analyze_Package_Name but iterates over all the names
3727 --------------------------
3728 -- Analyze_Package_Name --
3729 --------------------------
3731 procedure Analyze_Package_Name
(Clause
: Node_Id
) is
3732 Pack
: constant Node_Id
:= Name
(Clause
);
3736 pragma Assert
(Nkind
(Clause
) = N_Use_Package_Clause
);
3739 -- Verify that the package standard is not directly named in a
3740 -- use_package_clause.
3742 if Nkind
(Parent
(Clause
)) = N_Compilation_Unit
3743 and then Nkind
(Pack
) = N_Expanded_Name
3745 Pref
:= Prefix
(Pack
);
3747 while Nkind
(Pref
) = N_Expanded_Name
loop
3748 Pref
:= Prefix
(Pref
);
3751 if Entity
(Pref
) = Standard_Standard
then
3753 ("predefined package Standard cannot appear in a context "
3757 end Analyze_Package_Name
;
3759 -------------------------------
3760 -- Analyze_Package_Name_List --
3761 -------------------------------
3763 procedure Analyze_Package_Name_List
(Head_Clause
: Node_Id
) is
3767 -- Due to the way source use clauses are split during parsing we are
3768 -- forced to simply iterate through all entities in scope until the
3769 -- clause representing the last name in the list is found.
3771 Curr
:= Head_Clause
;
3772 while Present
(Curr
) loop
3773 Analyze_Package_Name
(Curr
);
3775 -- Stop iterating over the names in the use clause when we are at
3778 exit when not More_Ids
(Curr
) and then Prev_Ids
(Curr
);
3781 end Analyze_Package_Name_List
;
3785 Ghost_Id
: Entity_Id
:= Empty
;
3786 Living_Id
: Entity_Id
:= Empty
;
3789 -- Start of processing for Analyze_Use_Package
3792 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3794 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3796 -- Use clause not allowed in a spec of a predefined package declaration
3797 -- except that packages whose file name starts a-n are OK (these are
3798 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3800 if Is_Predefined_Unit
(Current_Sem_Unit
)
3801 and then Get_Name_String
3802 (Unit_File_Name
(Current_Sem_Unit
)) (1 .. 3) /= "a-n"
3803 and then Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) =
3804 N_Package_Declaration
3806 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3809 -- Loop through all package names from the original use clause in
3810 -- order to analyze referenced packages. A use_package_clause with only
3811 -- one name does not have More_Ids or Prev_Ids set, while a clause with
3812 -- More_Ids only starts the chain produced by the parser.
3814 if not More_Ids
(N
) and then not Prev_Ids
(N
) then
3815 Analyze_Package_Name
(N
);
3817 elsif More_Ids
(N
) and then not Prev_Ids
(N
) then
3818 Analyze_Package_Name_List
(N
);
3821 if not Is_Entity_Name
(Name
(N
)) then
3822 Error_Msg_N
("& is not a package", Name
(N
));
3828 Chain_Use_Clause
(N
);
3831 Pack
:= Entity
(Name
(N
));
3833 -- There are many cases where scopes are manipulated during analysis, so
3834 -- check that Pack's current use clause has not already been chained
3835 -- before setting its previous use clause.
3837 if Ekind
(Pack
) = E_Package
3838 and then Present
(Current_Use_Clause
(Pack
))
3839 and then Current_Use_Clause
(Pack
) /= N
3840 and then No
(Prev_Use_Clause
(N
))
3841 and then Prev_Use_Clause
(Current_Use_Clause
(Pack
)) /= N
3843 Set_Prev_Use_Clause
(N
, Current_Use_Clause
(Pack
));
3846 -- Mark all entities as potentially use visible.
3848 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3849 if Ekind
(Pack
) = E_Generic_Package
then
3850 Error_Msg_N
-- CODEFIX
3851 ("a generic package is not allowed in a use clause", Name
(N
));
3853 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3855 Error_Msg_N
-- CODEFIX
3856 ("a generic subprogram is not allowed in a use clause",
3859 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3860 Error_Msg_N
-- CODEFIX
3861 ("a subprogram is not allowed in a use clause", Name
(N
));
3864 Error_Msg_N
("& is not allowed in a use clause", Name
(N
));
3868 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3869 Check_In_Previous_With_Clause
(N
, Name
(N
));
3872 Use_One_Package
(N
, Name
(N
));
3874 -- Capture the first Ghost package and the first living package
3876 if Is_Entity_Name
(Name
(N
)) then
3877 Pack
:= Entity
(Name
(N
));
3879 if Is_Ghost_Entity
(Pack
) then
3880 if No
(Ghost_Id
) then
3884 elsif No
(Living_Id
) then
3889 end Analyze_Use_Package
;
3891 ----------------------
3892 -- Analyze_Use_Type --
3893 ----------------------
3895 procedure Analyze_Use_Type
(N
: Node_Id
; Chain
: Boolean := True) is
3900 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3902 -- Chain clause to list of use clauses in current scope when flagged
3905 Chain_Use_Clause
(N
);
3908 -- Obtain the base type of the type denoted within the use_type_clause's
3911 Id
:= Subtype_Mark
(N
);
3913 E
:= Base_Type
(Entity
(Id
));
3915 -- There are many cases where a use_type_clause may be reanalyzed due to
3916 -- manipulation of the scope stack so we much guard against those cases
3917 -- here, otherwise, we must add the new use_type_clause to the previous
3918 -- use_type_clause chain in order to mark redundant use_type_clauses as
3921 if Present
(Current_Use_Clause
(E
))
3922 and then Current_Use_Clause
(E
) /= N
3923 and then No
(Prev_Use_Clause
(N
))
3925 Set_Prev_Use_Clause
(N
, Current_Use_Clause
(E
));
3928 -- If the Used_Operations list is already initialized, the clause has
3929 -- been analyzed previously, and it is being reinstalled, for example
3930 -- when the clause appears in a package spec and we are compiling the
3931 -- corresponding package body. In that case, make the entities on the
3932 -- existing list use_visible, and mark the corresponding types In_Use.
3934 if Present
(Used_Operations
(N
)) then
3939 Use_One_Type
(Subtype_Mark
(N
), Installed
=> True);
3941 Elmt
:= First_Elmt
(Used_Operations
(N
));
3942 while Present
(Elmt
) loop
3943 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3951 -- Otherwise, create new list and attach to it the operations that are
3952 -- made use-visible by the clause.
3954 Set_Used_Operations
(N
, New_Elmt_List
);
3957 if E
/= Any_Type
then
3960 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3961 if Nkind
(Id
) = N_Identifier
then
3962 Error_Msg_N
("type is not directly visible", Id
);
3964 elsif Is_Child_Unit
(Scope
(E
))
3965 and then Scope
(E
) /= System_Aux_Id
3967 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3972 -- If the use_type_clause appears in a compilation unit context,
3973 -- check whether it comes from a unit that may appear in a
3974 -- limited_with_clause, for a better error message.
3976 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3977 and then Nkind
(Id
) /= N_Identifier
3983 function Mentioned
(Nam
: Node_Id
) return Boolean;
3984 -- Check whether the prefix of expanded name for the type
3985 -- appears in the prefix of some limited_with_clause.
3991 function Mentioned
(Nam
: Node_Id
) return Boolean is
3993 return Nkind
(Name
(Item
)) = N_Selected_Component
3994 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3998 Pref
:= Prefix
(Id
);
3999 Item
:= First
(Context_Items
(Parent
(N
)));
4000 while Present
(Item
) and then Item
/= N
loop
4001 if Nkind
(Item
) = N_With_Clause
4002 and then Limited_Present
(Item
)
4003 and then Mentioned
(Pref
)
4006 (Get_Msg_Id
, "premature usage of incomplete type");
4015 Mark_Ghost_Clause
(N
);
4016 end Analyze_Use_Type
;
4018 ------------------------
4019 -- Attribute_Renaming --
4020 ------------------------
4022 procedure Attribute_Renaming
(N
: Node_Id
) is
4023 Loc
: constant Source_Ptr
:= Sloc
(N
);
4024 Nam
: constant Node_Id
:= Name
(N
);
4025 Spec
: constant Node_Id
:= Specification
(N
);
4026 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
4027 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
4029 Form_Num
: Nat
:= 0;
4030 Expr_List
: List_Id
:= No_List
;
4032 Attr_Node
: Node_Id
;
4033 Body_Node
: Node_Id
;
4034 Param_Spec
: Node_Id
;
4037 Generate_Definition
(New_S
);
4039 -- This procedure is called in the context of subprogram renaming, and
4040 -- thus the attribute must be one that is a subprogram. All of those
4041 -- have at least one formal parameter, with the exceptions of the GNAT
4042 -- attribute 'Img, which GNAT treats as renameable.
4044 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
4045 if Aname
/= Name_Img
then
4047 ("subprogram renaming an attribute must have formals", N
);
4052 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
4053 while Present
(Param_Spec
) loop
4054 Form_Num
:= Form_Num
+ 1;
4056 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
4057 Find_Type
(Parameter_Type
(Param_Spec
));
4059 -- The profile of the new entity denotes the base type (s) of
4060 -- the types given in the specification. For access parameters
4061 -- there are no subtypes involved.
4063 Rewrite
(Parameter_Type
(Param_Spec
),
4065 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
4068 if No
(Expr_List
) then
4069 Expr_List
:= New_List
;
4072 Append_To
(Expr_List
,
4073 Make_Identifier
(Loc
,
4074 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
4076 -- The expressions in the attribute reference are not freeze
4077 -- points. Neither is the attribute as a whole, see below.
4079 Set_Must_Not_Freeze
(Last
(Expr_List
));
4084 -- Immediate error if too many formals. Other mismatches in number or
4085 -- types of parameters are detected when we analyze the body of the
4086 -- subprogram that we construct.
4088 if Form_Num
> 2 then
4089 Error_Msg_N
("too many formals for attribute", N
);
4091 -- Error if the attribute reference has expressions that look like
4092 -- formal parameters.
4094 elsif Present
(Expressions
(Nam
)) then
4095 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
4098 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
4099 Name_Pos
, Name_Round
, Name_Scaling
,
4102 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
4103 and then Present
(Corresponding_Formal_Spec
(N
))
4106 ("generic actual cannot be attribute involving universal type",
4110 ("attribute involving a universal type cannot be renamed",
4115 -- Rewrite attribute node to have a list of expressions corresponding to
4116 -- the subprogram formals. A renaming declaration is not a freeze point,
4117 -- and the analysis of the attribute reference should not freeze the
4118 -- type of the prefix. We use the original node in the renaming so that
4119 -- its source location is preserved, and checks on stream attributes are
4120 -- properly applied.
4122 Attr_Node
:= Relocate_Node
(Nam
);
4123 Set_Expressions
(Attr_Node
, Expr_List
);
4125 Set_Must_Not_Freeze
(Attr_Node
);
4126 Set_Must_Not_Freeze
(Prefix
(Nam
));
4128 -- Case of renaming a function
4130 if Nkind
(Spec
) = N_Function_Specification
then
4131 if Is_Procedure_Attribute_Name
(Aname
) then
4132 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
4136 Find_Type
(Result_Definition
(Spec
));
4137 Rewrite
(Result_Definition
(Spec
),
4139 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
4142 Make_Subprogram_Body
(Loc
,
4143 Specification
=> Spec
,
4144 Declarations
=> New_List
,
4145 Handled_Statement_Sequence
=>
4146 Make_Handled_Sequence_Of_Statements
(Loc
,
4147 Statements
=> New_List
(
4148 Make_Simple_Return_Statement
(Loc
,
4149 Expression
=> Attr_Node
))));
4151 -- Case of renaming a procedure
4154 if not Is_Procedure_Attribute_Name
(Aname
) then
4155 Error_Msg_N
("attribute can only be renamed as function", Nam
);
4160 Make_Subprogram_Body
(Loc
,
4161 Specification
=> Spec
,
4162 Declarations
=> New_List
,
4163 Handled_Statement_Sequence
=>
4164 Make_Handled_Sequence_Of_Statements
(Loc
,
4165 Statements
=> New_List
(Attr_Node
)));
4168 -- Signal the ABE mechanism that the generated subprogram body has not
4169 -- ABE ramifications.
4171 Set_Was_Attribute_Reference
(Body_Node
);
4173 -- In case of tagged types we add the body of the generated function to
4174 -- the freezing actions of the type (because in the general case such
4175 -- type is still not frozen). We exclude from this processing generic
4176 -- formal subprograms found in instantiations.
4178 -- We must exclude restricted run-time libraries because
4179 -- entity AST_Handler is defined in package System.Aux_Dec which is not
4180 -- available in those platforms. Note that we cannot use the function
4181 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
4182 -- the ZFP run-time library is not defined as a profile, and we do not
4183 -- want to deal with AST_Handler in ZFP mode.
4185 if not Configurable_Run_Time_Mode
4186 and then not Present
(Corresponding_Formal_Spec
(N
))
4187 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
4190 P
: constant Node_Id
:= Prefix
(Nam
);
4193 -- The prefix of 'Img is an object that is evaluated for each call
4194 -- of the function that renames it.
4196 if Aname
= Name_Img
then
4197 Preanalyze_And_Resolve
(P
);
4199 -- For all other attribute renamings, the prefix is a subtype
4205 -- If the target type is not yet frozen, add the body to the
4206 -- actions to be elaborated at freeze time.
4208 if Is_Tagged_Type
(Etype
(P
))
4209 and then In_Open_Scopes
(Scope
(Etype
(P
)))
4211 Ensure_Freeze_Node
(Etype
(P
));
4212 Append_Freeze_Action
(Etype
(P
), Body_Node
);
4214 Rewrite
(N
, Body_Node
);
4216 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4220 -- Generic formal subprograms or AST_Handler renaming
4223 Rewrite
(N
, Body_Node
);
4225 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
4228 if Is_Compilation_Unit
(New_S
) then
4230 ("a library unit can only rename another library unit", N
);
4232 end Attribute_Renaming
;
4234 ----------------------
4235 -- Chain_Use_Clause --
4236 ----------------------
4238 procedure Chain_Use_Clause
(N
: Node_Id
) is
4239 Level
: Int
:= Scope_Stack
.Last
;
4245 if not Is_Compilation_Unit
(Current_Scope
)
4246 or else not Is_Child_Unit
(Current_Scope
)
4250 -- Common case for compilation unit
4252 elsif Defining_Entity
(N
=> Parent
(N
),
4253 Empty_On_Errors
=> True) = Current_Scope
4258 -- If declaration appears in some other scope, it must be in some
4259 -- parent unit when compiling a child.
4261 Pack
:= Defining_Entity
(Parent
(N
), Empty_On_Errors
=> True);
4263 if not In_Open_Scopes
(Pack
) then
4266 -- If the use clause appears in an ancestor and we are in the
4267 -- private part of the immediate parent, the use clauses are
4268 -- already installed.
4270 elsif Pack
/= Scope
(Current_Scope
)
4271 and then In_Private_Part
(Scope
(Current_Scope
))
4276 -- Find entry for parent unit in scope stack
4278 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4284 Set_Next_Use_Clause
(N
,
4285 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4286 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4287 end Chain_Use_Clause
;
4289 ---------------------------
4290 -- Check_Frozen_Renaming --
4291 ---------------------------
4293 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4298 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4301 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4303 if Is_Entity_Name
(Name
(N
)) then
4304 Old_S
:= Entity
(Name
(N
));
4306 if not Is_Frozen
(Old_S
)
4307 and then Operating_Mode
/= Check_Semantics
4309 Append_Freeze_Action
(Old_S
, B_Node
);
4311 Insert_After
(N
, B_Node
);
4315 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4317 ("subprogram used in renaming_as_body cannot be intrinsic",
4322 Insert_After
(N
, B_Node
);
4326 end Check_Frozen_Renaming
;
4328 -------------------------------
4329 -- Set_Entity_Or_Discriminal --
4330 -------------------------------
4332 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4336 -- If the entity is not a discriminant, or else expansion is disabled,
4337 -- simply set the entity.
4339 if not In_Spec_Expression
4340 or else Ekind
(E
) /= E_Discriminant
4341 or else Inside_A_Generic
4343 Set_Entity_With_Checks
(N
, E
);
4345 -- The replacement of a discriminant by the corresponding discriminal
4346 -- is not done for a task discriminant that appears in a default
4347 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4348 -- for details on their handling.
4350 elsif Is_Concurrent_Type
(Scope
(E
)) then
4353 and then not Nkind_In
(P
, N_Parameter_Specification
,
4354 N_Component_Declaration
)
4360 and then Nkind
(P
) = N_Parameter_Specification
4365 Set_Entity
(N
, Discriminal
(E
));
4368 -- Otherwise, this is a discriminant in a context in which
4369 -- it is a reference to the corresponding parameter of the
4370 -- init proc for the enclosing type.
4373 Set_Entity
(N
, Discriminal
(E
));
4375 end Set_Entity_Or_Discriminal
;
4377 -----------------------------------
4378 -- Check_In_Previous_With_Clause --
4379 -----------------------------------
4381 procedure Check_In_Previous_With_Clause
4385 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4390 Item
:= First
(Context_Items
(Parent
(N
)));
4391 while Present
(Item
) and then Item
/= N
loop
4392 if Nkind
(Item
) = N_With_Clause
4394 -- Protect the frontend against previous critical errors
4396 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4397 and then Entity
(Name
(Item
)) = Pack
4401 -- Find root library unit in with_clause
4403 while Nkind
(Par
) = N_Expanded_Name
loop
4404 Par
:= Prefix
(Par
);
4407 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4408 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4417 -- On exit, package is not mentioned in a previous with_clause.
4418 -- Check if its prefix is.
4420 if Nkind
(Nam
) = N_Expanded_Name
then
4421 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4423 elsif Pack
/= Any_Id
then
4424 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4426 end Check_In_Previous_With_Clause
;
4428 ---------------------------------
4429 -- Check_Library_Unit_Renaming --
4430 ---------------------------------
4432 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4436 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4439 -- Check for library unit. Note that we used to check for the scope
4440 -- being Standard here, but that was wrong for Standard itself.
4442 elsif not Is_Compilation_Unit
(Old_E
)
4443 and then not Is_Child_Unit
(Old_E
)
4445 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4447 -- Entities defined in Standard (operators and boolean literals) cannot
4448 -- be renamed as library units.
4450 elsif Scope
(Old_E
) = Standard_Standard
4451 and then Sloc
(Old_E
) = Standard_Location
4453 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4455 elsif Present
(Parent_Spec
(N
))
4456 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4457 and then not Is_Child_Unit
(Old_E
)
4460 ("renamed unit must be a child unit of generic parent", Name
(N
));
4462 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4463 and then Nkind
(Name
(N
)) = N_Expanded_Name
4464 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4465 and then Is_Generic_Unit
(Old_E
)
4468 ("renamed generic unit must be a library unit", Name
(N
));
4470 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4472 -- Inherit categorization flags
4474 New_E
:= Defining_Entity
(N
);
4475 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4476 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4477 Set_Is_Remote_Call_Interface
(New_E
,
4478 Is_Remote_Call_Interface
(Old_E
));
4479 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4480 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4482 end Check_Library_Unit_Renaming
;
4484 ------------------------
4485 -- Enclosing_Instance --
4486 ------------------------
4488 function Enclosing_Instance
return Entity_Id
is
4492 if not Is_Generic_Instance
(Current_Scope
) then
4496 S
:= Scope
(Current_Scope
);
4497 while S
/= Standard_Standard
loop
4498 if Is_Generic_Instance
(S
) then
4506 end Enclosing_Instance
;
4512 procedure End_Scope
is
4518 Id
:= First_Entity
(Current_Scope
);
4519 while Present
(Id
) loop
4520 -- An entity in the current scope is not necessarily the first one
4521 -- on its homonym chain. Find its predecessor if any,
4522 -- If it is an internal entity, it will not be in the visibility
4523 -- chain altogether, and there is nothing to unchain.
4525 if Id
/= Current_Entity
(Id
) then
4526 Prev
:= Current_Entity
(Id
);
4527 while Present
(Prev
)
4528 and then Present
(Homonym
(Prev
))
4529 and then Homonym
(Prev
) /= Id
4531 Prev
:= Homonym
(Prev
);
4534 -- Skip to end of loop if Id is not in the visibility chain
4536 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4544 Set_Is_Immediately_Visible
(Id
, False);
4546 Outer
:= Homonym
(Id
);
4547 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4548 Outer
:= Homonym
(Outer
);
4551 -- Reset homonym link of other entities, but do not modify link
4552 -- between entities in current scope, so that the back-end can have
4553 -- a proper count of local overloadings.
4556 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4558 elsif Scope
(Prev
) /= Scope
(Id
) then
4559 Set_Homonym
(Prev
, Outer
);
4566 -- If the scope generated freeze actions, place them before the
4567 -- current declaration and analyze them. Type declarations and
4568 -- the bodies of initialization procedures can generate such nodes.
4569 -- We follow the parent chain until we reach a list node, which is
4570 -- the enclosing list of declarations. If the list appears within
4571 -- a protected definition, move freeze nodes outside the protected
4575 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4579 L
: constant List_Id
:= Scope_Stack
.Table
4580 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4583 if Is_Itype
(Current_Scope
) then
4584 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4586 Decl
:= Parent
(Current_Scope
);
4591 while not (Is_List_Member
(Decl
))
4592 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4595 Decl
:= Parent
(Decl
);
4598 Insert_List_Before_And_Analyze
(Decl
, L
);
4606 ---------------------
4607 -- End_Use_Clauses --
4608 ---------------------
4610 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4614 -- Remove use_type_clauses first, because they affect the visibility of
4615 -- operators in subsequent used packages.
4618 while Present
(U
) loop
4619 if Nkind
(U
) = N_Use_Type_Clause
then
4623 Next_Use_Clause
(U
);
4627 while Present
(U
) loop
4628 if Nkind
(U
) = N_Use_Package_Clause
then
4629 End_Use_Package
(U
);
4632 Next_Use_Clause
(U
);
4634 end End_Use_Clauses
;
4636 ---------------------
4637 -- End_Use_Package --
4638 ---------------------
4640 procedure End_Use_Package
(N
: Node_Id
) is
4642 Pack_Name
: Node_Id
;
4646 function Is_Primitive_Operator_In_Use
4648 F
: Entity_Id
) return Boolean;
4649 -- Check whether Op is a primitive operator of a use-visible type
4651 ----------------------------------
4652 -- Is_Primitive_Operator_In_Use --
4653 ----------------------------------
4655 function Is_Primitive_Operator_In_Use
4657 F
: Entity_Id
) return Boolean
4659 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4661 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4662 end Is_Primitive_Operator_In_Use
;
4664 -- Start of processing for End_Use_Package
4667 Pack_Name
:= Name
(N
);
4669 -- Test that Pack_Name actually denotes a package before processing
4671 if Is_Entity_Name
(Pack_Name
)
4672 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4674 Pack
:= Entity
(Pack_Name
);
4676 if In_Open_Scopes
(Pack
) then
4679 elsif not Redundant_Use
(Pack_Name
) then
4680 Set_In_Use
(Pack
, False);
4681 Set_Current_Use_Clause
(Pack
, Empty
);
4683 Id
:= First_Entity
(Pack
);
4684 while Present
(Id
) loop
4686 -- Preserve use-visibility of operators that are primitive
4687 -- operators of a type that is use-visible through an active
4690 if Nkind
(Id
) = N_Defining_Operator_Symbol
4692 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4694 (Present
(Next_Formal
(First_Formal
(Id
)))
4696 Is_Primitive_Operator_In_Use
4697 (Id
, Next_Formal
(First_Formal
(Id
)))))
4701 Set_Is_Potentially_Use_Visible
(Id
, False);
4704 if Is_Private_Type
(Id
)
4705 and then Present
(Full_View
(Id
))
4707 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4713 if Present
(Renamed_Object
(Pack
)) then
4714 Set_In_Use
(Renamed_Object
(Pack
), False);
4715 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4718 if Chars
(Pack
) = Name_System
4719 and then Scope
(Pack
) = Standard_Standard
4720 and then Present_System_Aux
4722 Id
:= First_Entity
(System_Aux_Id
);
4723 while Present
(Id
) loop
4724 Set_Is_Potentially_Use_Visible
(Id
, False);
4726 if Is_Private_Type
(Id
)
4727 and then Present
(Full_View
(Id
))
4729 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4735 Set_In_Use
(System_Aux_Id
, False);
4738 Set_Redundant_Use
(Pack_Name
, False);
4742 if Present
(Hidden_By_Use_Clause
(N
)) then
4743 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4744 while Present
(Elmt
) loop
4746 E
: constant Entity_Id
:= Node
(Elmt
);
4749 -- Reset either Use_Visibility or Direct_Visibility, depending
4750 -- on how the entity was hidden by the use clause.
4752 if In_Use
(Scope
(E
))
4753 and then Used_As_Generic_Actual
(Scope
(E
))
4755 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4757 Set_Is_Immediately_Visible
(Node
(Elmt
));
4764 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4766 end End_Use_Package
;
4772 procedure End_Use_Type
(N
: Node_Id
) is
4777 -- Start of processing for End_Use_Type
4780 Id
:= Subtype_Mark
(N
);
4782 -- A call to Rtsfind may occur while analyzing a use_type_clause, in
4783 -- which case the type marks are not resolved yet, so guard against that
4786 if Is_Entity_Name
(Id
) and then Present
(Entity
(Id
)) then
4789 if T
= Any_Type
or else From_Limited_With
(T
) then
4792 -- Note that the use_type_clause may mention a subtype of the type
4793 -- whose primitive operations have been made visible. Here as
4794 -- elsewhere, it is the base type that matters for visibility.
4796 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4799 elsif not Redundant_Use
(Id
) then
4800 Set_In_Use
(T
, False);
4801 Set_In_Use
(Base_Type
(T
), False);
4802 Set_Current_Use_Clause
(T
, Empty
);
4803 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4807 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4811 Elmt
:= First_Elmt
(Used_Operations
(N
));
4812 while Present
(Elmt
) loop
4813 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4819 --------------------
4820 -- Entity_Of_Unit --
4821 --------------------
4823 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
is
4825 if Nkind
(U
) = N_Package_Instantiation
and then Analyzed
(U
) then
4826 return Defining_Entity
(Instance_Spec
(U
));
4828 return Defining_Entity
(U
);
4832 ----------------------
4833 -- Find_Direct_Name --
4834 ----------------------
4836 procedure Find_Direct_Name
(N
: Node_Id
) is
4841 Homonyms
: Entity_Id
;
4842 -- Saves start of homonym chain
4844 Inst
: Entity_Id
:= Empty
;
4845 -- Enclosing instance, if any
4847 Nvis_Entity
: Boolean;
4848 -- Set True to indicate that there is at least one entity on the homonym
4849 -- chain which, while not visible, is visible enough from the user point
4850 -- of view to warrant an error message of "not visible" rather than
4853 Nvis_Is_Private_Subprg
: Boolean := False;
4854 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4855 -- effect concerning library subprograms has been detected. Used to
4856 -- generate the precise error message.
4858 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4859 -- Returns true if the entity is an actual for a package that is itself
4860 -- an actual for a formal package of the current instance. Such an
4861 -- entity requires special handling because it may be use-visible but
4862 -- hides directly visible entities defined outside the instance, because
4863 -- the corresponding formal did so in the generic.
4865 function Is_Actual_Parameter
return Boolean;
4866 -- This function checks if the node N is an identifier that is an actual
4867 -- parameter of a procedure call. If so it returns True, otherwise it
4868 -- return False. The reason for this check is that at this stage we do
4869 -- not know what procedure is being called if the procedure might be
4870 -- overloaded, so it is premature to go setting referenced flags or
4871 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4872 -- for that processing
4874 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4875 -- This function determines whether a reference to the entity E, which
4876 -- is not visible, can reasonably be considered to be known to the
4877 -- writer of the reference. This is a heuristic test, used only for
4878 -- the purposes of figuring out whether we prefer to complain that an
4879 -- entity is undefined or invisible (and identify the declaration of
4880 -- the invisible entity in the latter case). The point here is that we
4881 -- don't want to complain that something is invisible and then point to
4882 -- something entirely mysterious to the writer.
4884 procedure Nvis_Messages
;
4885 -- Called if there are no visible entries for N, but there is at least
4886 -- one non-directly visible, or hidden declaration. This procedure
4887 -- outputs an appropriate set of error messages.
4889 procedure Undefined
(Nvis
: Boolean);
4890 -- This function is called if the current node has no corresponding
4891 -- visible entity or entities. The value set in Msg indicates whether
4892 -- an error message was generated (multiple error messages for the
4893 -- same variable are generally suppressed, see body for details).
4894 -- Msg is True if an error message was generated, False if not. This
4895 -- value is used by the caller to determine whether or not to output
4896 -- additional messages where appropriate. The parameter is set False
4897 -- to get the message "X is undefined", and True to get the message
4898 -- "X is not visible".
4900 -------------------------
4901 -- From_Actual_Package --
4902 -------------------------
4904 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4905 Scop
: constant Entity_Id
:= Scope
(E
);
4906 -- Declared scope of candidate entity
4908 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4909 -- Recursive function that does the work and examines actuals of
4910 -- actual packages of current instance.
4912 ------------------------
4913 -- Declared_In_Actual --
4914 ------------------------
4916 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4920 if No
(Associated_Formal_Package
(Pack
)) then
4924 Act
:= First_Entity
(Pack
);
4925 while Present
(Act
) loop
4926 if Renamed_Object
(Pack
) = Scop
then
4929 -- Check for end of list of actuals
4931 elsif Ekind
(Act
) = E_Package
4932 and then Renamed_Object
(Act
) = Pack
4936 elsif Ekind
(Act
) = E_Package
4937 and then Declared_In_Actual
(Act
)
4947 end Declared_In_Actual
;
4953 -- Start of processing for From_Actual_Package
4956 if not In_Instance
then
4960 Inst
:= Current_Scope
;
4961 while Present
(Inst
)
4962 and then Ekind
(Inst
) /= E_Package
4963 and then not Is_Generic_Instance
(Inst
)
4965 Inst
:= Scope
(Inst
);
4972 Act
:= First_Entity
(Inst
);
4973 while Present
(Act
) loop
4974 if Ekind
(Act
) = E_Package
4975 and then Declared_In_Actual
(Act
)
4985 end From_Actual_Package
;
4987 -------------------------
4988 -- Is_Actual_Parameter --
4989 -------------------------
4991 function Is_Actual_Parameter
return Boolean is
4994 Nkind
(N
) = N_Identifier
4996 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4998 (Nkind
(Parent
(N
)) = N_Parameter_Association
4999 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
5000 and then Nkind
(Parent
(Parent
(N
))) =
5001 N_Procedure_Call_Statement
));
5002 end Is_Actual_Parameter
;
5004 -------------------------
5005 -- Known_But_Invisible --
5006 -------------------------
5008 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
5009 Fname
: File_Name_Type
;
5012 -- Entities in Standard are always considered to be known
5014 if Sloc
(E
) <= Standard_Location
then
5017 -- An entity that does not come from source is always considered
5018 -- to be unknown, since it is an artifact of code expansion.
5020 elsif not Comes_From_Source
(E
) then
5023 -- In gnat internal mode, we consider all entities known. The
5024 -- historical reason behind this discrepancy is not known??? But the
5025 -- only effect is to modify the error message given, so it is not
5026 -- critical. Since it only affects the exact wording of error
5027 -- messages in illegal programs, we do not mention this as an
5028 -- effect of -gnatg, since it is not a language modification.
5030 elsif GNAT_Mode
then
5034 -- Here we have an entity that is not from package Standard, and
5035 -- which comes from Source. See if it comes from an internal file.
5037 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
5039 -- Case of from internal file
5041 if In_Internal_Unit
(E
) then
5043 -- Private part entities in internal files are never considered
5044 -- to be known to the writer of normal application code.
5046 if Is_Hidden
(E
) then
5050 -- Entities from System packages other than System and
5051 -- System.Storage_Elements are not considered to be known.
5052 -- System.Auxxxx files are also considered known to the user.
5054 -- Should refine this at some point to generally distinguish
5055 -- between known and unknown internal files ???
5057 Get_Name_String
(Fname
);
5062 Name_Buffer
(1 .. 2) /= "s-"
5064 Name_Buffer
(3 .. 8) = "stoele"
5066 Name_Buffer
(3 .. 5) = "aux";
5068 -- If not an internal file, then entity is definitely known, even if
5069 -- it is in a private part (the message generated will note that it
5070 -- is in a private part).
5075 end Known_But_Invisible
;
5081 procedure Nvis_Messages
is
5082 Comp_Unit
: Node_Id
;
5084 Found
: Boolean := False;
5085 Hidden
: Boolean := False;
5089 -- Ada 2005 (AI-262): Generate a precise error concerning the
5090 -- Beaujolais effect that was previously detected
5092 if Nvis_Is_Private_Subprg
then
5094 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
5095 and then Ekind
(E2
) = E_Function
5096 and then Scope
(E2
) = Standard_Standard
5097 and then Has_Private_With
(E2
));
5099 -- Find the sloc corresponding to the private with'ed unit
5101 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
5102 Error_Msg_Sloc
:= No_Location
;
5104 Item
:= First
(Context_Items
(Comp_Unit
));
5105 while Present
(Item
) loop
5106 if Nkind
(Item
) = N_With_Clause
5107 and then Private_Present
(Item
)
5108 and then Entity
(Name
(Item
)) = E2
5110 Error_Msg_Sloc
:= Sloc
(Item
);
5117 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
5119 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
5123 Undefined
(Nvis
=> True);
5127 -- First loop does hidden declarations
5130 while Present
(Ent
) loop
5131 if Is_Potentially_Use_Visible
(Ent
) then
5133 Error_Msg_N
-- CODEFIX
5134 ("multiple use clauses cause hiding!", N
);
5138 Error_Msg_Sloc
:= Sloc
(Ent
);
5139 Error_Msg_N
-- CODEFIX
5140 ("hidden declaration#!", N
);
5143 Ent
:= Homonym
(Ent
);
5146 -- If we found hidden declarations, then that's enough, don't
5147 -- bother looking for non-visible declarations as well.
5153 -- Second loop does non-directly visible declarations
5156 while Present
(Ent
) loop
5157 if not Is_Potentially_Use_Visible
(Ent
) then
5159 -- Do not bother the user with unknown entities
5161 if not Known_But_Invisible
(Ent
) then
5165 Error_Msg_Sloc
:= Sloc
(Ent
);
5167 -- Output message noting that there is a non-visible
5168 -- declaration, distinguishing the private part case.
5170 if Is_Hidden
(Ent
) then
5171 Error_Msg_N
("non-visible (private) declaration#!", N
);
5173 -- If the entity is declared in a generic package, it
5174 -- cannot be visible, so there is no point in adding it
5175 -- to the list of candidates if another homograph from a
5176 -- non-generic package has been seen.
5178 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
5184 Error_Msg_N
-- CODEFIX
5185 ("non-visible declaration#!", N
);
5187 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
5191 if Is_Compilation_Unit
(Ent
)
5193 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
5195 Error_Msg_Qual_Level
:= 99;
5196 Error_Msg_NE
-- CODEFIX
5197 ("\\missing `WITH &;`", N
, Ent
);
5198 Error_Msg_Qual_Level
:= 0;
5201 if Ekind
(Ent
) = E_Discriminant
5202 and then Present
(Corresponding_Discriminant
(Ent
))
5203 and then Scope
(Corresponding_Discriminant
(Ent
)) =
5207 ("inherited discriminant not allowed here" &
5208 " (RM 3.8 (12), 3.8.1 (6))!", N
);
5212 -- Set entity and its containing package as referenced. We
5213 -- can't be sure of this, but this seems a better choice
5214 -- to avoid unused entity messages.
5216 if Comes_From_Source
(Ent
) then
5217 Set_Referenced
(Ent
);
5218 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
5223 Ent
:= Homonym
(Ent
);
5232 procedure Undefined
(Nvis
: Boolean) is
5233 Emsg
: Error_Msg_Id
;
5236 -- We should never find an undefined internal name. If we do, then
5237 -- see if we have previous errors. If so, ignore on the grounds that
5238 -- it is probably a cascaded message (e.g. a block label from a badly
5239 -- formed block). If no previous errors, then we have a real internal
5240 -- error of some kind so raise an exception.
5242 if Is_Internal_Name
(Chars
(N
)) then
5243 if Total_Errors_Detected
/= 0 then
5246 raise Program_Error
;
5250 -- A very specialized error check, if the undefined variable is
5251 -- a case tag, and the case type is an enumeration type, check
5252 -- for a possible misspelling, and if so, modify the identifier
5254 -- Named aggregate should also be handled similarly ???
5256 if Nkind
(N
) = N_Identifier
5257 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5260 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5261 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5266 if Is_Enumeration_Type
(Case_Typ
)
5267 and then not Is_Standard_Character_Type
(Case_Typ
)
5269 Lit
:= First_Literal
(Case_Typ
);
5270 Get_Name_String
(Chars
(Lit
));
5272 if Chars
(Lit
) /= Chars
(N
)
5273 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5275 Error_Msg_Node_2
:= Lit
;
5276 Error_Msg_N
-- CODEFIX
5277 ("& is undefined, assume misspelling of &", N
);
5278 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5282 Lit
:= Next_Literal
(Lit
);
5287 -- Normal processing
5289 Set_Entity
(N
, Any_Id
);
5290 Set_Etype
(N
, Any_Type
);
5292 -- We use the table Urefs to keep track of entities for which we
5293 -- have issued errors for undefined references. Multiple errors
5294 -- for a single name are normally suppressed, however we modify
5295 -- the error message to alert the programmer to this effect.
5297 for J
in Urefs
.First
.. Urefs
.Last
loop
5298 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5299 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5300 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5302 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5304 if Urefs
.Table
(J
).Nvis
then
5305 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5306 "& is not visible (more references follow)");
5308 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5309 "& is undefined (more references follow)");
5312 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5315 -- Although we will set Msg False, and thus suppress the
5316 -- message, we also set Error_Posted True, to avoid any
5317 -- cascaded messages resulting from the undefined reference.
5320 Set_Error_Posted
(N
, True);
5325 -- If entry not found, this is first undefined occurrence
5328 Error_Msg_N
("& is not visible!", N
);
5332 Error_Msg_N
("& is undefined!", N
);
5335 -- A very bizarre special check, if the undefined identifier
5336 -- is put or put_line, then add a special error message (since
5337 -- this is a very common error for beginners to make).
5339 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5340 Error_Msg_N
-- CODEFIX
5341 ("\\possible missing `WITH Ada.Text_'I'O; " &
5342 "USE Ada.Text_'I'O`!", N
);
5344 -- Another special check if N is the prefix of a selected
5345 -- component which is a known unit, add message complaining
5346 -- about missing with for this unit.
5348 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5349 and then N
= Prefix
(Parent
(N
))
5350 and then Is_Known_Unit
(Parent
(N
))
5352 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5353 Error_Msg_N
-- CODEFIX
5354 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5357 -- Now check for possible misspellings
5361 Ematch
: Entity_Id
:= Empty
;
5363 Last_Name_Id
: constant Name_Id
:=
5364 Name_Id
(Nat
(First_Name_Id
) +
5365 Name_Entries_Count
- 1);
5368 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5369 E
:= Get_Name_Entity_Id
(Nam
);
5372 and then (Is_Immediately_Visible
(E
)
5374 Is_Potentially_Use_Visible
(E
))
5376 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5383 if Present
(Ematch
) then
5384 Error_Msg_NE
-- CODEFIX
5385 ("\possible misspelling of&", N
, Ematch
);
5390 -- Make entry in undefined references table unless the full errors
5391 -- switch is set, in which case by refraining from generating the
5392 -- table entry, we guarantee that we get an error message for every
5393 -- undefined reference. The entry is not added if we are ignoring
5396 if not All_Errors_Mode
and then Ignore_Errors_Enable
= 0 then
5409 Is_Assignment_LHS
: constant Boolean := Is_LHS
(N
) = Yes
;
5411 Nested_Inst
: Entity_Id
:= Empty
;
5412 -- The entity of a nested instance which appears within Inst (if any)
5414 -- Start of processing for Find_Direct_Name
5417 -- If the entity pointer is already set, this is an internal node, or
5418 -- a node that is analyzed more than once, after a tree modification.
5419 -- In such a case there is no resolution to perform, just set the type.
5421 if Present
(Entity
(N
)) then
5422 if Is_Type
(Entity
(N
)) then
5423 Set_Etype
(N
, Entity
(N
));
5427 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5430 -- One special case here. If the Etype field is already set,
5431 -- and references the packed array type corresponding to the
5432 -- etype of the referenced entity, then leave it alone. This
5433 -- happens for trees generated from Exp_Pakd, where expressions
5434 -- can be deliberately "mis-typed" to the packed array type.
5436 if Is_Array_Type
(Entyp
)
5437 and then Is_Packed
(Entyp
)
5438 and then Present
(Etype
(N
))
5439 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5443 -- If not that special case, then just reset the Etype
5446 Set_Etype
(N
, Etype
(Entity
(N
)));
5451 -- Although the marking of use clauses happens at the end of
5452 -- Find_Direct_Name, a certain case where a generic actual satisfies
5453 -- a use clause must be checked here due to how the generic machinery
5454 -- handles the analysis of said actuals.
5457 and then Nkind
(Parent
(N
)) = N_Generic_Association
5459 Mark_Use_Clauses
(Entity
(N
));
5465 -- Preserve relevant elaboration-related attributes of the context which
5466 -- are no longer available or very expensive to recompute once analysis,
5467 -- resolution, and expansion are over.
5469 if Nkind
(N
) = N_Identifier
then
5470 Mark_Elaboration_Attributes
5475 -- Here if Entity pointer was not set, we need full visibility analysis
5476 -- First we generate debugging output if the debug E flag is set.
5478 if Debug_Flag_E
then
5479 Write_Str
("Looking for ");
5480 Write_Name
(Chars
(N
));
5484 Homonyms
:= Current_Entity
(N
);
5485 Nvis_Entity
:= False;
5488 while Present
(E
) loop
5490 -- If entity is immediately visible or potentially use visible, then
5491 -- process the entity and we are done.
5493 if Is_Immediately_Visible
(E
) then
5494 goto Immediately_Visible_Entity
;
5496 elsif Is_Potentially_Use_Visible
(E
) then
5497 goto Potentially_Use_Visible_Entity
;
5499 -- Note if a known but invisible entity encountered
5501 elsif Known_But_Invisible
(E
) then
5502 Nvis_Entity
:= True;
5505 -- Move to next entity in chain and continue search
5510 -- If no entries on homonym chain that were potentially visible,
5511 -- and no entities reasonably considered as non-visible, then
5512 -- we have a plain undefined reference, with no additional
5513 -- explanation required.
5515 if not Nvis_Entity
then
5516 Undefined
(Nvis
=> False);
5518 -- Otherwise there is at least one entry on the homonym chain that
5519 -- is reasonably considered as being known and non-visible.
5527 -- Processing for a potentially use visible entry found. We must search
5528 -- the rest of the homonym chain for two reasons. First, if there is a
5529 -- directly visible entry, then none of the potentially use-visible
5530 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5531 -- for the case of multiple potentially use-visible entries hiding one
5532 -- another and as a result being non-directly visible (RM 8.4(11)).
5534 <<Potentially_Use_Visible_Entity
>> declare
5535 Only_One_Visible
: Boolean := True;
5536 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5540 while Present
(E2
) loop
5541 if Is_Immediately_Visible
(E2
) then
5543 -- If the use-visible entity comes from the actual for a
5544 -- formal package, it hides a directly visible entity from
5545 -- outside the instance.
5547 if From_Actual_Package
(E
)
5548 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5553 goto Immediately_Visible_Entity
;
5556 elsif Is_Potentially_Use_Visible
(E2
) then
5557 Only_One_Visible
:= False;
5558 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5560 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5561 -- that can occur in private_with clauses. Example:
5564 -- private with B; package A is
5565 -- package C is function B return Integer;
5567 -- V1 : Integer := B;
5568 -- private function B return Integer;
5569 -- V2 : Integer := B;
5572 -- V1 resolves to A.B, but V2 resolves to library unit B
5574 elsif Ekind
(E2
) = E_Function
5575 and then Scope
(E2
) = Standard_Standard
5576 and then Has_Private_With
(E2
)
5578 Only_One_Visible
:= False;
5579 All_Overloadable
:= False;
5580 Nvis_Is_Private_Subprg
:= True;
5587 -- On falling through this loop, we have checked that there are no
5588 -- immediately visible entities. Only_One_Visible is set if exactly
5589 -- one potentially use visible entity exists. All_Overloadable is
5590 -- set if all the potentially use visible entities are overloadable.
5591 -- The condition for legality is that either there is one potentially
5592 -- use visible entity, or if there is more than one, then all of them
5593 -- are overloadable.
5595 if Only_One_Visible
or All_Overloadable
then
5598 -- If there is more than one potentially use-visible entity and at
5599 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5600 -- Note that E points to the first such entity on the homonym list.
5603 -- If one of the entities is declared in an actual package, it
5604 -- was visible in the generic, and takes precedence over other
5605 -- entities that are potentially use-visible. The same applies
5606 -- if the entity is declared in a local instantiation of the
5607 -- current instance.
5611 -- Find the current instance
5613 Inst
:= Current_Scope
;
5614 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5615 if Is_Generic_Instance
(Inst
) then
5619 Inst
:= Scope
(Inst
);
5622 -- Reexamine the candidate entities, giving priority to those
5623 -- that were visible within the generic.
5626 while Present
(E2
) loop
5627 Nested_Inst
:= Nearest_Enclosing_Instance
(E2
);
5629 -- The entity is declared within an actual package, or in a
5630 -- nested instance. The ">=" accounts for the case where the
5631 -- current instance and the nested instance are the same.
5633 if From_Actual_Package
(E2
)
5634 or else (Present
(Nested_Inst
)
5635 and then Scope_Depth
(Nested_Inst
) >=
5648 elsif Is_Predefined_Unit
(Current_Sem_Unit
) then
5649 -- A use clause in the body of a system file creates conflict
5650 -- with some entity in a user scope, while rtsfind is active.
5651 -- Keep only the entity coming from another predefined unit.
5654 while Present
(E2
) loop
5655 if In_Predefined_Unit
(E2
) then
5663 -- Entity must exist because predefined unit is correct
5665 raise Program_Error
;
5674 -- Come here with E set to the first immediately visible entity on
5675 -- the homonym chain. This is the one we want unless there is another
5676 -- immediately visible entity further on in the chain for an inner
5677 -- scope (RM 8.3(8)).
5679 <<Immediately_Visible_Entity
>> declare
5684 -- Find scope level of initial entity. When compiling through
5685 -- Rtsfind, the previous context is not completely invisible, and
5686 -- an outer entity may appear on the chain, whose scope is below
5687 -- the entry for Standard that delimits the current scope stack.
5688 -- Indicate that the level for this spurious entry is outside of
5689 -- the current scope stack.
5691 Level
:= Scope_Stack
.Last
;
5693 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5694 exit when Scop
= Scope
(E
);
5696 exit when Scop
= Standard_Standard
;
5699 -- Now search remainder of homonym chain for more inner entry
5700 -- If the entity is Standard itself, it has no scope, and we
5701 -- compare it with the stack entry directly.
5704 while Present
(E2
) loop
5705 if Is_Immediately_Visible
(E2
) then
5707 -- If a generic package contains a local declaration that
5708 -- has the same name as the generic, there may be a visibility
5709 -- conflict in an instance, where the local declaration must
5710 -- also hide the name of the corresponding package renaming.
5711 -- We check explicitly for a package declared by a renaming,
5712 -- whose renamed entity is an instance that is on the scope
5713 -- stack, and that contains a homonym in the same scope. Once
5714 -- we have found it, we know that the package renaming is not
5715 -- immediately visible, and that the identifier denotes the
5716 -- other entity (and its homonyms if overloaded).
5718 if Scope
(E
) = Scope
(E2
)
5719 and then Ekind
(E
) = E_Package
5720 and then Present
(Renamed_Object
(E
))
5721 and then Is_Generic_Instance
(Renamed_Object
(E
))
5722 and then In_Open_Scopes
(Renamed_Object
(E
))
5723 and then Comes_From_Source
(N
)
5725 Set_Is_Immediately_Visible
(E
, False);
5729 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5730 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5731 or else Scope_Stack
.Table
(J
).Entity
= E2
5744 -- At the end of that loop, E is the innermost immediately
5745 -- visible entity, so we are all set.
5748 -- Come here with entity found, and stored in E
5752 -- Check violation of No_Wide_Characters restriction
5754 Check_Wide_Character_Restriction
(E
, N
);
5756 -- When distribution features are available (Get_PCS_Name /=
5757 -- Name_No_DSA), a remote access-to-subprogram type is converted
5758 -- into a record type holding whatever information is needed to
5759 -- perform a remote call on an RCI subprogram. In that case we
5760 -- rewrite any occurrence of the RAS type into the equivalent record
5761 -- type here. 'Access attribute references and RAS dereferences are
5762 -- then implemented using specific TSSs. However when distribution is
5763 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5764 -- generation of these TSSs, and we must keep the RAS type in its
5765 -- original access-to-subprogram form (since all calls through a
5766 -- value of such type will be local anyway in the absence of a PCS).
5768 if Comes_From_Source
(N
)
5769 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5770 and then Ekind
(E
) = E_Access_Subprogram_Type
5771 and then Expander_Active
5772 and then Get_PCS_Name
/= Name_No_DSA
5774 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5778 -- Set the entity. Note that the reason we call Set_Entity for the
5779 -- overloadable case, as opposed to Set_Entity_With_Checks is
5780 -- that in the overloaded case, the initial call can set the wrong
5781 -- homonym. The call that sets the right homonym is in Sem_Res and
5782 -- that call does use Set_Entity_With_Checks, so we don't miss
5785 if Is_Overloadable
(E
) then
5788 Set_Entity_With_Checks
(N
, E
);
5794 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5797 if Debug_Flag_E
then
5798 Write_Str
(" found ");
5799 Write_Entity_Info
(E
, " ");
5802 -- If the Ekind of the entity is Void, it means that all homonyms
5803 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5804 -- test is skipped if the current scope is a record and the name is
5805 -- a pragma argument expression (case of Atomic and Volatile pragmas
5806 -- and possibly other similar pragmas added later, which are allowed
5807 -- to reference components in the current record).
5809 if Ekind
(E
) = E_Void
5811 (not Is_Record_Type
(Current_Scope
)
5812 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5814 Premature_Usage
(N
);
5816 -- If the entity is overloadable, collect all interpretations of the
5817 -- name for subsequent overload resolution. We optimize a bit here to
5818 -- do this only if we have an overloadable entity that is not on its
5819 -- own on the homonym chain.
5821 elsif Is_Overloadable
(E
)
5822 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5824 Collect_Interps
(N
);
5826 -- If no homonyms were visible, the entity is unambiguous
5828 if not Is_Overloaded
(N
) then
5829 if not Is_Actual_Parameter
then
5830 Generate_Reference
(E
, N
);
5834 -- Case of non-overloadable entity, set the entity providing that
5835 -- we do not have the case of a discriminant reference within a
5836 -- default expression. Such references are replaced with the
5837 -- corresponding discriminal, which is the formal corresponding to
5838 -- to the discriminant in the initialization procedure.
5841 -- Entity is unambiguous, indicate that it is referenced here
5843 -- For a renaming of an object, always generate simple reference,
5844 -- we don't try to keep track of assignments in this case, except
5845 -- in SPARK mode where renamings are traversed for generating
5846 -- local effects of subprograms.
5849 and then Present
(Renamed_Object
(E
))
5850 and then not GNATprove_Mode
5852 Generate_Reference
(E
, N
);
5854 -- If the renamed entity is a private protected component,
5855 -- reference the original component as well. This needs to be
5856 -- done because the private renamings are installed before any
5857 -- analysis has occurred. Reference to a private component will
5858 -- resolve to the renaming and the original component will be
5859 -- left unreferenced, hence the following.
5861 if Is_Prival
(E
) then
5862 Generate_Reference
(Prival_Link
(E
), N
);
5865 -- One odd case is that we do not want to set the Referenced flag
5866 -- if the entity is a label, and the identifier is the label in
5867 -- the source, since this is not a reference from the point of
5868 -- view of the user.
5870 elsif Nkind
(Parent
(N
)) = N_Label
then
5872 R
: constant Boolean := Referenced
(E
);
5875 -- Generate reference unless this is an actual parameter
5876 -- (see comment below)
5878 if Is_Actual_Parameter
then
5879 Generate_Reference
(E
, N
);
5880 Set_Referenced
(E
, R
);
5884 -- Normal case, not a label: generate reference
5887 if not Is_Actual_Parameter
then
5889 -- Package or generic package is always a simple reference
5891 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5892 Generate_Reference
(E
, N
, 'r');
5894 -- Else see if we have a left hand side
5899 Generate_Reference
(E
, N
, 'm');
5902 Generate_Reference
(E
, N
, 'r');
5904 -- If we don't know now, generate reference later
5907 Deferred_References
.Append
((E
, N
));
5913 Set_Entity_Or_Discriminal
(N
, E
);
5915 -- The name may designate a generalized reference, in which case
5916 -- the dereference interpretation will be included. Context is
5917 -- one in which a name is legal.
5919 if Ada_Version
>= Ada_2012
5921 (Nkind
(Parent
(N
)) in N_Subexpr
5922 or else Nkind_In
(Parent
(N
), N_Assignment_Statement
,
5923 N_Object_Declaration
,
5924 N_Parameter_Association
))
5926 Check_Implicit_Dereference
(N
, Etype
(E
));
5931 -- Mark relevant use-type and use-package clauses as effective if the
5932 -- node in question is not overloaded and therefore does not require
5935 -- Note: Generic actual subprograms do not follow the normal resolution
5936 -- path, so ignore the fact that they are overloaded and mark them
5939 if Nkind
(N
) not in N_Subexpr
or else not Is_Overloaded
(N
) then
5940 Mark_Use_Clauses
(N
);
5943 -- Come here with entity set
5946 Check_Restriction_No_Use_Of_Entity
(N
);
5948 -- Annotate the tree by creating a variable reference marker in case the
5949 -- original variable reference is folded or optimized away. The variable
5950 -- reference marker is automatically saved for later examination by the
5951 -- ABE Processing phase. Variable references which act as actuals in a
5952 -- call require special processing and are left to Resolve_Actuals. The
5953 -- reference is a write when it appears on the left hand side of an
5956 if not Within_Subprogram_Call
(N
) then
5957 Build_Variable_Reference_Marker
5959 Read
=> not Is_Assignment_LHS
,
5960 Write
=> Is_Assignment_LHS
);
5962 end Find_Direct_Name
;
5964 ------------------------
5965 -- Find_Expanded_Name --
5966 ------------------------
5968 -- This routine searches the homonym chain of the entity until it finds
5969 -- an entity declared in the scope denoted by the prefix. If the entity
5970 -- is private, it may nevertheless be immediately visible, if we are in
5971 -- the scope of its declaration.
5973 procedure Find_Expanded_Name
(N
: Node_Id
) is
5974 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean;
5975 -- Determine whether expanded name Nod appears within a pragma which is
5976 -- a suitable context for an abstract view of a state or variable. The
5977 -- following pragmas fall in this category:
5984 -- In addition, pragma Abstract_State is also considered suitable even
5985 -- though it is an illegal context for an abstract view as this allows
5986 -- for proper resolution of abstract views of variables. This illegal
5987 -- context is later flagged in the analysis of indicator Part_Of.
5989 -----------------------------
5990 -- In_Abstract_View_Pragma --
5991 -----------------------------
5993 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean is
5997 -- Climb the parent chain looking for a pragma
6000 while Present
(Par
) loop
6001 if Nkind
(Par
) = N_Pragma
then
6002 if Nam_In
(Pragma_Name_Unmapped
(Par
),
6003 Name_Abstract_State
,
6007 Name_Refined_Depends
,
6008 Name_Refined_Global
)
6012 -- Otherwise the pragma is not a legal context for an abstract
6019 -- Prevent the search from going too far
6021 elsif Is_Body_Or_Package_Declaration
(Par
) then
6025 Par
:= Parent
(Par
);
6029 end In_Abstract_View_Pragma
;
6033 Is_Assignment_LHS
: constant Boolean := Is_LHS
(N
) = Yes
;
6034 Selector
: constant Node_Id
:= Selector_Name
(N
);
6036 Candidate
: Entity_Id
:= Empty
;
6040 -- Start of processing for Find_Expanded_Name
6043 P_Name
:= Entity
(Prefix
(N
));
6045 -- If the prefix is a renamed package, look for the entity in the
6046 -- original package.
6048 if Ekind
(P_Name
) = E_Package
6049 and then Present
(Renamed_Object
(P_Name
))
6051 P_Name
:= Renamed_Object
(P_Name
);
6053 -- Rewrite node with entity field pointing to renamed object
6055 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
6056 Set_Entity
(Prefix
(N
), P_Name
);
6058 -- If the prefix is an object of a concurrent type, look for
6059 -- the entity in the associated task or protected type.
6061 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
6062 P_Name
:= Etype
(P_Name
);
6065 Id
:= Current_Entity
(Selector
);
6068 Is_New_Candidate
: Boolean;
6071 while Present
(Id
) loop
6072 if Scope
(Id
) = P_Name
then
6074 Is_New_Candidate
:= True;
6076 -- Handle abstract views of states and variables. These are
6077 -- acceptable candidates only when the reference to the view
6078 -- appears in certain pragmas.
6080 if Ekind
(Id
) = E_Abstract_State
6081 and then From_Limited_With
(Id
)
6082 and then Present
(Non_Limited_View
(Id
))
6084 if In_Abstract_View_Pragma
(N
) then
6085 Candidate
:= Non_Limited_View
(Id
);
6086 Is_New_Candidate
:= True;
6088 -- Hide the candidate because it is not used in a proper
6093 Is_New_Candidate
:= False;
6097 -- Ada 2005 (AI-217): Handle shadow entities associated with
6098 -- types declared in limited-withed nested packages. We don't need
6099 -- to handle E_Incomplete_Subtype entities because the entities
6100 -- in the limited view are always E_Incomplete_Type and
6101 -- E_Class_Wide_Type entities (see Build_Limited_Views).
6103 -- Regarding the expression used to evaluate the scope, it
6104 -- is important to note that the limited view also has shadow
6105 -- entities associated nested packages. For this reason the
6106 -- correct scope of the entity is the scope of the real entity.
6107 -- The non-limited view may itself be incomplete, in which case
6108 -- get the full view if available.
6110 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
6111 and then From_Limited_With
(Id
)
6112 and then Present
(Non_Limited_View
(Id
))
6113 and then Scope
(Non_Limited_View
(Id
)) = P_Name
6115 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
6116 Is_New_Candidate
:= True;
6118 -- An unusual case arises with a fully qualified name for an
6119 -- entity local to a generic child unit package, within an
6120 -- instantiation of that package. The name of the unit now
6121 -- denotes the renaming created within the instance. This is
6122 -- only relevant in an instance body, see below.
6124 elsif Is_Generic_Instance
(Scope
(Id
))
6125 and then In_Open_Scopes
(Scope
(Id
))
6126 and then In_Instance_Body
6127 and then Ekind
(Scope
(Id
)) = E_Package
6128 and then Ekind
(Id
) = E_Package
6129 and then Renamed_Entity
(Id
) = Scope
(Id
)
6130 and then Is_Immediately_Visible
(P_Name
)
6132 Is_New_Candidate
:= True;
6135 Is_New_Candidate
:= False;
6138 if Is_New_Candidate
then
6140 -- If entity is a child unit, either it is a visible child of
6141 -- the prefix, or we are in the body of a generic prefix, as
6142 -- will happen when a child unit is instantiated in the body
6143 -- of a generic parent. This is because the instance body does
6144 -- not restore the full compilation context, given that all
6145 -- non-local references have been captured.
6147 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
6148 exit when Is_Visible_Lib_Unit
(Id
)
6149 or else (Is_Child_Unit
(Id
)
6150 and then In_Open_Scopes
(Scope
(Id
))
6151 and then In_Instance_Body
);
6153 exit when not Is_Hidden
(Id
);
6156 exit when Is_Immediately_Visible
(Id
);
6164 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6165 and then Is_Generic_Instance
(P_Name
)
6167 -- Expanded name denotes entity in (instance of) generic subprogram.
6168 -- The entity may be in the subprogram instance, or may denote one of
6169 -- the formals, which is declared in the enclosing wrapper package.
6171 P_Name
:= Scope
(P_Name
);
6173 Id
:= Current_Entity
(Selector
);
6174 while Present
(Id
) loop
6175 exit when Scope
(Id
) = P_Name
;
6180 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
6181 Set_Etype
(N
, Any_Type
);
6183 -- If we are looking for an entity defined in System, try to find it
6184 -- in the child package that may have been provided as an extension
6185 -- to System. The Extend_System pragma will have supplied the name of
6186 -- the extension, which may have to be loaded.
6188 if Chars
(P_Name
) = Name_System
6189 and then Scope
(P_Name
) = Standard_Standard
6190 and then Present
(System_Extend_Unit
)
6191 and then Present_System_Aux
(N
)
6193 Set_Entity
(Prefix
(N
), System_Aux_Id
);
6194 Find_Expanded_Name
(N
);
6197 -- There is an implicit instance of the predefined operator in
6198 -- the given scope. The operator entity is defined in Standard.
6199 -- Has_Implicit_Operator makes the node into an Expanded_Name.
6201 elsif Nkind
(Selector
) = N_Operator_Symbol
6202 and then Has_Implicit_Operator
(N
)
6206 -- If there is no literal defined in the scope denoted by the
6207 -- prefix, the literal may belong to (a type derived from)
6208 -- Standard_Character, for which we have no explicit literals.
6210 elsif Nkind
(Selector
) = N_Character_Literal
6211 and then Has_Implicit_Character_Literal
(N
)
6216 -- If the prefix is a single concurrent object, use its name in
6217 -- the error message, rather than that of the anonymous type.
6219 if Is_Concurrent_Type
(P_Name
)
6220 and then Is_Internal_Name
(Chars
(P_Name
))
6222 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
6224 Error_Msg_Node_2
:= P_Name
;
6227 if P_Name
= System_Aux_Id
then
6228 P_Name
:= Scope
(P_Name
);
6229 Set_Entity
(Prefix
(N
), P_Name
);
6232 if Present
(Candidate
) then
6234 -- If we know that the unit is a child unit we can give a more
6235 -- accurate error message.
6237 if Is_Child_Unit
(Candidate
) then
6239 -- If the candidate is a private child unit and we are in
6240 -- the visible part of a public unit, specialize the error
6241 -- message. There might be a private with_clause for it,
6242 -- but it is not currently active.
6244 if Is_Private_Descendant
(Candidate
)
6245 and then Ekind
(Current_Scope
) = E_Package
6246 and then not In_Private_Part
(Current_Scope
)
6247 and then not Is_Private_Descendant
(Current_Scope
)
6250 ("private child unit& is not visible here", Selector
);
6252 -- Normal case where we have a missing with for a child unit
6255 Error_Msg_Qual_Level
:= 99;
6256 Error_Msg_NE
-- CODEFIX
6257 ("missing `WITH &;`", Selector
, Candidate
);
6258 Error_Msg_Qual_Level
:= 0;
6261 -- Here we don't know that this is a child unit
6264 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
6268 -- Within the instantiation of a child unit, the prefix may
6269 -- denote the parent instance, but the selector has the name
6270 -- of the original child. That is to say, when A.B appears
6271 -- within an instantiation of generic child unit B, the scope
6272 -- stack includes an instance of A (P_Name) and an instance
6273 -- of B under some other name. We scan the scope to find this
6274 -- child instance, which is the desired entity.
6275 -- Note that the parent may itself be a child instance, if
6276 -- the reference is of the form A.B.C, in which case A.B has
6277 -- already been rewritten with the proper entity.
6279 if In_Open_Scopes
(P_Name
)
6280 and then Is_Generic_Instance
(P_Name
)
6283 Gen_Par
: constant Entity_Id
:=
6284 Generic_Parent
(Specification
6285 (Unit_Declaration_Node
(P_Name
)));
6286 S
: Entity_Id
:= Current_Scope
;
6290 for J
in reverse 0 .. Scope_Stack
.Last
loop
6291 S
:= Scope_Stack
.Table
(J
).Entity
;
6293 exit when S
= Standard_Standard
;
6295 if Ekind_In
(S
, E_Function
,
6300 Generic_Parent
(Specification
6301 (Unit_Declaration_Node
(S
)));
6303 -- Check that P is a generic child of the generic
6304 -- parent of the prefix.
6307 and then Chars
(P
) = Chars
(Selector
)
6308 and then Scope
(P
) = Gen_Par
6319 -- If this is a selection from Ada, System or Interfaces, then
6320 -- we assume a missing with for the corresponding package.
6322 if Is_Known_Unit
(N
) then
6323 if not Error_Posted
(N
) then
6324 Error_Msg_Node_2
:= Selector
;
6325 Error_Msg_N
-- CODEFIX
6326 ("missing `WITH &.&;`", Prefix
(N
));
6329 -- If this is a selection from a dummy package, then suppress
6330 -- the error message, of course the entity is missing if the
6331 -- package is missing.
6333 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
6336 -- Here we have the case of an undefined component
6339 -- The prefix may hide a homonym in the context that
6340 -- declares the desired entity. This error can use a
6341 -- specialized message.
6343 if In_Open_Scopes
(P_Name
) then
6345 H
: constant Entity_Id
:= Homonym
(P_Name
);
6349 and then Is_Compilation_Unit
(H
)
6351 (Is_Immediately_Visible
(H
)
6352 or else Is_Visible_Lib_Unit
(H
))
6354 Id
:= First_Entity
(H
);
6355 while Present
(Id
) loop
6356 if Chars
(Id
) = Chars
(Selector
) then
6357 Error_Msg_Qual_Level
:= 99;
6358 Error_Msg_Name_1
:= Chars
(Selector
);
6360 ("% not declared in&", N
, P_Name
);
6362 ("\use fully qualified name starting with "
6363 & "Standard to make& visible", N
, H
);
6364 Error_Msg_Qual_Level
:= 0;
6372 -- If not found, standard error message
6374 Error_Msg_NE
("& not declared in&", N
, Selector
);
6380 -- Might be worth specializing the case when the prefix
6381 -- is a limited view.
6382 -- ... not declared in limited view of...
6384 Error_Msg_NE
("& not declared in&", N
, Selector
);
6387 -- Check for misspelling of some entity in prefix
6389 Id
:= First_Entity
(P_Name
);
6390 while Present
(Id
) loop
6391 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6392 and then not Is_Internal_Name
(Chars
(Id
))
6394 Error_Msg_NE
-- CODEFIX
6395 ("possible misspelling of&", Selector
, Id
);
6402 -- Specialize the message if this may be an instantiation
6403 -- of a child unit that was not mentioned in the context.
6405 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6406 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6407 and then Is_Compilation_Unit
6408 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6410 Error_Msg_Node_2
:= Selector
;
6411 Error_Msg_N
-- CODEFIX
6412 ("\missing `WITH &.&;`", Prefix
(N
));
6422 if Comes_From_Source
(N
)
6423 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6424 and then Ekind
(Id
) = E_Access_Subprogram_Type
6425 and then Present
(Equivalent_Type
(Id
))
6427 -- If we are not actually generating distribution code (i.e. the
6428 -- current PCS is the dummy non-distributed version), then the
6429 -- Equivalent_Type will be missing, and Id should be treated as
6430 -- a regular access-to-subprogram type.
6432 Id
:= Equivalent_Type
(Id
);
6433 Set_Chars
(Selector
, Chars
(Id
));
6436 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6438 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6439 if From_Limited_With
(Id
)
6440 or else Is_Type
(Id
)
6441 or else Ekind
(Id
) = E_Package
6446 ("limited withed package can only be used to access incomplete "
6451 if Is_Task_Type
(P_Name
)
6452 and then ((Ekind
(Id
) = E_Entry
6453 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6455 (Ekind
(Id
) = E_Entry_Family
6457 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6459 -- If both the task type and the entry are in scope, this may still
6460 -- be the expanded name of an entry formal.
6462 if In_Open_Scopes
(Id
)
6463 and then Nkind
(Parent
(N
)) = N_Selected_Component
6468 -- It is an entry call after all, either to the current task
6469 -- (which will deadlock) or to an enclosing task.
6471 Analyze_Selected_Component
(N
);
6476 Change_Selected_Component_To_Expanded_Name
(N
);
6478 -- Preserve relevant elaboration-related attributes of the context which
6479 -- are no longer available or very expensive to recompute once analysis,
6480 -- resolution, and expansion are over.
6482 Mark_Elaboration_Attributes
6486 -- Set appropriate type
6488 if Is_Type
(Id
) then
6491 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6494 -- Do style check and generate reference, but skip both steps if this
6495 -- entity has homonyms, since we may not have the right homonym set yet.
6496 -- The proper homonym will be set during the resolve phase.
6498 if Has_Homonym
(Id
) then
6502 Set_Entity_Or_Discriminal
(N
, Id
);
6506 Generate_Reference
(Id
, N
, 'm');
6509 Generate_Reference
(Id
, N
, 'r');
6512 Deferred_References
.Append
((Id
, N
));
6516 -- Check for violation of No_Wide_Characters
6518 Check_Wide_Character_Restriction
(Id
, N
);
6520 -- If the Ekind of the entity is Void, it means that all homonyms are
6521 -- hidden from all visibility (RM 8.3(5,14-20)).
6523 if Ekind
(Id
) = E_Void
then
6524 Premature_Usage
(N
);
6526 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6528 H
: Entity_Id
:= Homonym
(Id
);
6531 while Present
(H
) loop
6532 if Scope
(H
) = Scope
(Id
)
6533 and then (not Is_Hidden
(H
)
6534 or else Is_Immediately_Visible
(H
))
6536 Collect_Interps
(N
);
6543 -- If an extension of System is present, collect possible explicit
6544 -- overloadings declared in the extension.
6546 if Chars
(P_Name
) = Name_System
6547 and then Scope
(P_Name
) = Standard_Standard
6548 and then Present
(System_Extend_Unit
)
6549 and then Present_System_Aux
(N
)
6551 H
:= Current_Entity
(Id
);
6553 while Present
(H
) loop
6554 if Scope
(H
) = System_Aux_Id
then
6555 Add_One_Interp
(N
, H
, Etype
(H
));
6564 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6565 and then Scope
(Id
) /= Standard_Standard
6567 -- In addition to user-defined operators in the given scope, there
6568 -- may be an implicit instance of the predefined operator. The
6569 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6570 -- and added to the interpretations. Procedure Add_One_Interp will
6571 -- determine which hides which.
6573 if Has_Implicit_Operator
(N
) then
6578 -- If there is a single interpretation for N we can generate a
6579 -- reference to the unique entity found.
6581 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6582 Generate_Reference
(Id
, N
);
6585 -- Mark relevant use-type and use-package clauses as effective if the
6586 -- node in question is not overloaded and therefore does not require
6589 if Nkind
(N
) not in N_Subexpr
or else not Is_Overloaded
(N
) then
6590 Mark_Use_Clauses
(N
);
6593 Check_Restriction_No_Use_Of_Entity
(N
);
6595 -- Annotate the tree by creating a variable reference marker in case the
6596 -- original variable reference is folded or optimized away. The variable
6597 -- reference marker is automatically saved for later examination by the
6598 -- ABE Processing phase. Variable references which act as actuals in a
6599 -- call require special processing and are left to Resolve_Actuals. The
6600 -- reference is a write when it appears on the left hand side of an
6603 if not Within_Subprogram_Call
(N
) then
6604 Build_Variable_Reference_Marker
6606 Read
=> not Is_Assignment_LHS
,
6607 Write
=> Is_Assignment_LHS
);
6609 end Find_Expanded_Name
;
6611 --------------------
6612 -- Find_Most_Prev --
6613 --------------------
6615 function Find_Most_Prev
(Use_Clause
: Node_Id
) return Node_Id
is
6619 -- Loop through the Prev_Use_Clause chain
6622 while Present
(Prev_Use_Clause
(Curr
)) loop
6623 Curr
:= Prev_Use_Clause
(Curr
);
6629 -------------------------
6630 -- Find_Renamed_Entity --
6631 -------------------------
6633 function Find_Renamed_Entity
6637 Is_Actual
: Boolean := False) return Entity_Id
6640 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6646 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6647 -- If the renamed entity is an implicit operator, check whether it is
6648 -- visible because its operand type is properly visible. This check
6649 -- applies to explicit renamed entities that appear in the source in a
6650 -- renaming declaration or a formal subprogram instance, but not to
6651 -- default generic actuals with a name.
6653 function Report_Overload
return Entity_Id
;
6654 -- List possible interpretations, and specialize message in the
6655 -- case of a generic actual.
6657 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6658 -- Determine whether a candidate subprogram is defined within the
6659 -- enclosing instance. If yes, it has precedence over outer candidates.
6661 --------------------------
6662 -- Is_Visible_Operation --
6663 --------------------------
6665 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6671 if Ekind
(Op
) /= E_Operator
6672 or else Scope
(Op
) /= Standard_Standard
6673 or else (In_Instance
6674 and then (not Is_Actual
6675 or else Present
(Enclosing_Instance
)))
6680 -- For a fixed point type operator, check the resulting type,
6681 -- because it may be a mixed mode integer * fixed operation.
6683 if Present
(Next_Formal
(First_Formal
(New_S
)))
6684 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6686 Typ
:= Etype
(New_S
);
6688 Typ
:= Etype
(First_Formal
(New_S
));
6691 Btyp
:= Base_Type
(Typ
);
6693 if Nkind
(Nam
) /= N_Expanded_Name
then
6694 return (In_Open_Scopes
(Scope
(Btyp
))
6695 or else Is_Potentially_Use_Visible
(Btyp
)
6696 or else In_Use
(Btyp
)
6697 or else In_Use
(Scope
(Btyp
)));
6700 Scop
:= Entity
(Prefix
(Nam
));
6702 if Ekind
(Scop
) = E_Package
6703 and then Present
(Renamed_Object
(Scop
))
6705 Scop
:= Renamed_Object
(Scop
);
6708 -- Operator is visible if prefix of expanded name denotes
6709 -- scope of type, or else type is defined in System_Aux
6710 -- and the prefix denotes System.
6712 return Scope
(Btyp
) = Scop
6713 or else (Scope
(Btyp
) = System_Aux_Id
6714 and then Scope
(Scope
(Btyp
)) = Scop
);
6717 end Is_Visible_Operation
;
6723 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6727 Sc
:= Scope
(Inner
);
6728 while Sc
/= Standard_Standard
loop
6739 ---------------------
6740 -- Report_Overload --
6741 ---------------------
6743 function Report_Overload
return Entity_Id
is
6746 Error_Msg_NE
-- CODEFIX
6747 ("ambiguous actual subprogram&, " &
6748 "possible interpretations:", N
, Nam
);
6750 Error_Msg_N
-- CODEFIX
6751 ("ambiguous subprogram, " &
6752 "possible interpretations:", N
);
6755 List_Interps
(Nam
, N
);
6757 end Report_Overload
;
6759 -- Start of processing for Find_Renamed_Entity
6763 Candidate_Renaming
:= Empty
;
6765 if Is_Overloaded
(Nam
) then
6766 Get_First_Interp
(Nam
, Ind
, It
);
6767 while Present
(It
.Nam
) loop
6768 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6769 and then Is_Visible_Operation
(It
.Nam
)
6771 if Old_S
/= Any_Id
then
6773 -- Note: The call to Disambiguate only happens if a
6774 -- previous interpretation was found, in which case I1
6775 -- has received a value.
6777 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6779 if It1
= No_Interp
then
6780 Inst
:= Enclosing_Instance
;
6782 if Present
(Inst
) then
6783 if Within
(It
.Nam
, Inst
) then
6784 if Within
(Old_S
, Inst
) then
6786 -- Choose the innermost subprogram, which would
6787 -- have hidden the outer one in the generic.
6789 if Scope_Depth
(It
.Nam
) <
6798 elsif Within
(Old_S
, Inst
) then
6802 return Report_Overload
;
6805 -- If not within an instance, ambiguity is real
6808 return Report_Overload
;
6822 Present
(First_Formal
(It
.Nam
))
6823 and then Present
(First_Formal
(New_S
))
6824 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6825 Base_Type
(Etype
(First_Formal
(New_S
))))
6827 Candidate_Renaming
:= It
.Nam
;
6830 Get_Next_Interp
(Ind
, It
);
6833 Set_Entity
(Nam
, Old_S
);
6835 if Old_S
/= Any_Id
then
6836 Set_Is_Overloaded
(Nam
, False);
6839 -- Non-overloaded case
6843 and then Present
(Enclosing_Instance
)
6844 and then Entity_Matches_Spec
(Entity
(Nam
), New_S
)
6846 Old_S
:= Entity
(Nam
);
6848 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6849 Candidate_Renaming
:= New_S
;
6851 if Is_Visible_Operation
(Entity
(Nam
)) then
6852 Old_S
:= Entity
(Nam
);
6855 elsif Present
(First_Formal
(Entity
(Nam
)))
6856 and then Present
(First_Formal
(New_S
))
6857 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6858 Base_Type
(Etype
(First_Formal
(New_S
))))
6860 Candidate_Renaming
:= Entity
(Nam
);
6865 end Find_Renamed_Entity
;
6867 -----------------------------
6868 -- Find_Selected_Component --
6869 -----------------------------
6871 procedure Find_Selected_Component
(N
: Node_Id
) is
6872 P
: constant Node_Id
:= Prefix
(N
);
6875 -- Entity denoted by prefix
6882 function Available_Subtype
return Boolean;
6883 -- A small optimization: if the prefix is constrained and the component
6884 -- is an array type we may already have a usable subtype for it, so we
6885 -- can use it rather than generating a new one, because the bounds
6886 -- will be the values of the discriminants and not discriminant refs.
6887 -- This simplifies value tracing in GNATProve. For consistency, both
6888 -- the entity name and the subtype come from the constrained component.
6890 -- This is only used in GNATProve mode: when generating code it may be
6891 -- necessary to create an itype in the scope of use of the selected
6892 -- component, e.g. in the context of a expanded record equality.
6894 function Is_Reference_In_Subunit
return Boolean;
6895 -- In a subunit, the scope depth is not a proper measure of hiding,
6896 -- because the context of the proper body may itself hide entities in
6897 -- parent units. This rare case requires inspecting the tree directly
6898 -- because the proper body is inserted in the main unit and its context
6899 -- is simply added to that of the parent.
6901 -----------------------
6902 -- Available_Subtype --
6903 -----------------------
6905 function Available_Subtype
return Boolean is
6909 if GNATprove_Mode
then
6910 Comp
:= First_Entity
(Etype
(P
));
6911 while Present
(Comp
) loop
6912 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6913 Set_Etype
(N
, Etype
(Comp
));
6914 Set_Entity
(Selector_Name
(N
), Comp
);
6915 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6919 Next_Component
(Comp
);
6924 end Available_Subtype
;
6926 -----------------------------
6927 -- Is_Reference_In_Subunit --
6928 -----------------------------
6930 function Is_Reference_In_Subunit
return Boolean is
6932 Comp_Unit
: Node_Id
;
6936 while Present
(Comp_Unit
)
6937 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6939 Comp_Unit
:= Parent
(Comp_Unit
);
6942 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6946 -- Now check whether the package is in the context of the subunit
6948 Clause
:= First
(Context_Items
(Comp_Unit
));
6949 while Present
(Clause
) loop
6950 if Nkind
(Clause
) = N_With_Clause
6951 and then Entity
(Name
(Clause
)) = P_Name
6956 Clause
:= Next
(Clause
);
6960 end Is_Reference_In_Subunit
;
6962 -- Start of processing for Find_Selected_Component
6967 if Nkind
(P
) = N_Error
then
6971 -- Selector name cannot be a character literal or an operator symbol in
6972 -- SPARK, except for the operator symbol in a renaming.
6974 if Restriction_Check_Required
(SPARK_05
) then
6975 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6976 Check_SPARK_05_Restriction
6977 ("character literal cannot be prefixed", N
);
6978 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6979 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6981 Check_SPARK_05_Restriction
6982 ("operator symbol cannot be prefixed", N
);
6986 -- If the selector already has an entity, the node has been constructed
6987 -- in the course of expansion, and is known to be valid. Do not verify
6988 -- that it is defined for the type (it may be a private component used
6989 -- in the expansion of record equality).
6991 if Present
(Entity
(Selector_Name
(N
))) then
6992 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6994 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6995 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6999 Set_Etype
(Sel_Name
, Etype
(Selector
));
7001 if not Is_Entity_Name
(P
) then
7005 -- Build an actual subtype except for the first parameter
7006 -- of an init proc, where this actual subtype is by
7007 -- definition incorrect, since the object is uninitialized
7008 -- (and does not even have defined discriminants etc.)
7010 if Is_Entity_Name
(P
)
7011 and then Ekind
(Entity
(P
)) = E_Function
7013 Nam
:= New_Copy
(P
);
7015 if Is_Overloaded
(P
) then
7016 Save_Interps
(P
, Nam
);
7019 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
7021 Analyze_Selected_Component
(N
);
7024 elsif Ekind
(Selector
) = E_Component
7025 and then (not Is_Entity_Name
(P
)
7026 or else Chars
(Entity
(P
)) /= Name_uInit
)
7028 -- Check if we already have an available subtype we can use
7030 if Ekind
(Etype
(P
)) = E_Record_Subtype
7031 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
7032 and then Is_Array_Type
(Etype
(Selector
))
7033 and then not Is_Packed
(Etype
(Selector
))
7034 and then Available_Subtype
7038 -- Do not build the subtype when referencing components of
7039 -- dispatch table wrappers. Required to avoid generating
7040 -- elaboration code with HI runtimes.
7042 elsif RTU_Loaded
(Ada_Tags
)
7044 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
7045 and then Scope
(Selector
) =
7046 RTE
(RE_Dispatch_Table_Wrapper
))
7048 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
7049 and then Scope
(Selector
) =
7050 RTE
(RE_No_Dispatch_Table_Wrapper
)))
7055 Build_Actual_Subtype_Of_Component
7056 (Etype
(Selector
), N
);
7063 if No
(C_Etype
) then
7064 C_Etype
:= Etype
(Selector
);
7066 Insert_Action
(N
, C_Etype
);
7067 C_Etype
:= Defining_Identifier
(C_Etype
);
7070 Set_Etype
(N
, C_Etype
);
7073 -- If this is the name of an entry or protected operation, and
7074 -- the prefix is an access type, insert an explicit dereference,
7075 -- so that entry calls are treated uniformly.
7077 if Is_Access_Type
(Etype
(P
))
7078 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
7081 New_P
: constant Node_Id
:=
7082 Make_Explicit_Dereference
(Sloc
(P
),
7083 Prefix
=> Relocate_Node
(P
));
7086 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
7090 -- If the selected component appears within a default expression
7091 -- and it has an actual subtype, the pre-analysis has not yet
7092 -- completed its analysis, because Insert_Actions is disabled in
7093 -- that context. Within the init proc of the enclosing type we
7094 -- must complete this analysis, if an actual subtype was created.
7096 elsif Inside_Init_Proc
then
7098 Typ
: constant Entity_Id
:= Etype
(N
);
7099 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
7101 if Nkind
(Decl
) = N_Subtype_Declaration
7102 and then not Analyzed
(Decl
)
7103 and then Is_List_Member
(Decl
)
7104 and then No
(Parent
(Decl
))
7107 Insert_Action
(N
, Decl
);
7114 elsif Is_Entity_Name
(P
) then
7115 P_Name
:= Entity
(P
);
7117 -- The prefix may denote an enclosing type which is the completion
7118 -- of an incomplete type declaration.
7120 if Is_Type
(P_Name
) then
7121 Set_Entity
(P
, Get_Full_View
(P_Name
));
7122 Set_Etype
(P
, Entity
(P
));
7123 P_Name
:= Entity
(P
);
7126 P_Type
:= Base_Type
(Etype
(P
));
7128 if Debug_Flag_E
then
7129 Write_Str
("Found prefix type to be ");
7130 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
7133 -- The designated type may be a limited view with no components.
7134 -- Check whether the non-limited view is available, because in some
7135 -- cases this will not be set when installing the context. Rewrite
7136 -- the node by introducing an explicit dereference at once, and
7137 -- setting the type of the rewritten prefix to the non-limited view
7138 -- of the original designated type.
7140 if Is_Access_Type
(P_Type
) then
7142 Desig_Typ
: constant Entity_Id
:=
7143 Directly_Designated_Type
(P_Type
);
7146 if Is_Incomplete_Type
(Desig_Typ
)
7147 and then From_Limited_With
(Desig_Typ
)
7148 and then Present
(Non_Limited_View
(Desig_Typ
))
7151 Make_Explicit_Dereference
(Sloc
(P
),
7152 Prefix
=> Relocate_Node
(P
)));
7154 Set_Etype
(P
, Get_Full_View
(Non_Limited_View
(Desig_Typ
)));
7155 P_Type
:= Etype
(P
);
7160 -- First check for components of a record object (not the
7161 -- result of a call, which is handled below).
7163 if Is_Appropriate_For_Record
(P_Type
)
7164 and then not Is_Overloadable
(P_Name
)
7165 and then not Is_Type
(P_Name
)
7167 -- Selected component of record. Type checking will validate
7168 -- name of selector.
7170 -- ??? Could we rewrite an implicit dereference into an explicit
7173 Analyze_Selected_Component
(N
);
7175 -- Reference to type name in predicate/invariant expression
7177 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
7178 and then not In_Open_Scopes
(P_Name
)
7179 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
7180 or else not In_Open_Scopes
(Etype
(P_Name
)))
7182 -- Call to protected operation or entry. Type checking is
7183 -- needed on the prefix.
7185 Analyze_Selected_Component
(N
);
7187 elsif (In_Open_Scopes
(P_Name
)
7188 and then Ekind
(P_Name
) /= E_Void
7189 and then not Is_Overloadable
(P_Name
))
7190 or else (Is_Concurrent_Type
(Etype
(P_Name
))
7191 and then In_Open_Scopes
(Etype
(P_Name
)))
7193 -- Prefix denotes an enclosing loop, block, or task, i.e. an
7194 -- enclosing construct that is not a subprogram or accept.
7196 -- A special case: a protected body may call an operation
7197 -- on an external object of the same type, in which case it
7198 -- is not an expanded name. If the prefix is the type itself,
7199 -- or the context is a single synchronized object it can only
7200 -- be interpreted as an expanded name.
7202 if Is_Concurrent_Type
(Etype
(P_Name
)) then
7204 or else Present
(Anonymous_Object
(Etype
(P_Name
)))
7206 Find_Expanded_Name
(N
);
7209 Analyze_Selected_Component
(N
);
7214 Find_Expanded_Name
(N
);
7217 elsif Ekind
(P_Name
) = E_Package
then
7218 Find_Expanded_Name
(N
);
7220 elsif Is_Overloadable
(P_Name
) then
7222 -- The subprogram may be a renaming (of an enclosing scope) as
7223 -- in the case of the name of the generic within an instantiation.
7225 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
7226 and then Present
(Alias
(P_Name
))
7227 and then Is_Generic_Instance
(Alias
(P_Name
))
7229 P_Name
:= Alias
(P_Name
);
7232 if Is_Overloaded
(P
) then
7234 -- The prefix must resolve to a unique enclosing construct
7237 Found
: Boolean := False;
7242 Get_First_Interp
(P
, Ind
, It
);
7243 while Present
(It
.Nam
) loop
7244 if In_Open_Scopes
(It
.Nam
) then
7247 "prefix must be unique enclosing scope", N
);
7248 Set_Entity
(N
, Any_Id
);
7249 Set_Etype
(N
, Any_Type
);
7258 Get_Next_Interp
(Ind
, It
);
7263 if In_Open_Scopes
(P_Name
) then
7264 Set_Entity
(P
, P_Name
);
7265 Set_Is_Overloaded
(P
, False);
7266 Find_Expanded_Name
(N
);
7269 -- If no interpretation as an expanded name is possible, it
7270 -- must be a selected component of a record returned by a
7271 -- function call. Reformat prefix as a function call, the rest
7272 -- is done by type resolution.
7274 -- Error if the prefix is procedure or entry, as is P.X
7276 if Ekind
(P_Name
) /= E_Function
7278 (not Is_Overloaded
(P
)
7279 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
7281 -- Prefix may mention a package that is hidden by a local
7282 -- declaration: let the user know. Scan the full homonym
7283 -- chain, the candidate package may be anywhere on it.
7285 if Present
(Homonym
(Current_Entity
(P_Name
))) then
7286 P_Name
:= Current_Entity
(P_Name
);
7288 while Present
(P_Name
) loop
7289 exit when Ekind
(P_Name
) = E_Package
;
7290 P_Name
:= Homonym
(P_Name
);
7293 if Present
(P_Name
) then
7294 if not Is_Reference_In_Subunit
then
7295 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
7297 ("package& is hidden by declaration#", N
, P_Name
);
7300 Set_Entity
(Prefix
(N
), P_Name
);
7301 Find_Expanded_Name
(N
);
7305 P_Name
:= Entity
(Prefix
(N
));
7310 ("invalid prefix in selected component&", N
, P_Name
);
7311 Change_Selected_Component_To_Expanded_Name
(N
);
7312 Set_Entity
(N
, Any_Id
);
7313 Set_Etype
(N
, Any_Type
);
7315 -- Here we have a function call, so do the reformatting
7318 Nam
:= New_Copy
(P
);
7319 Save_Interps
(P
, Nam
);
7321 -- We use Replace here because this is one of those cases
7322 -- where the parser has missclassified the node, and we fix
7323 -- things up and then do the semantic analysis on the fixed
7324 -- up node. Normally we do this using one of the Sinfo.CN
7325 -- routines, but this is too tricky for that.
7327 -- Note that using Rewrite would be wrong, because we would
7328 -- have a tree where the original node is unanalyzed, and
7329 -- this violates the required interface for ASIS.
7332 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
7334 -- Now analyze the reformatted node
7338 -- If the prefix is illegal after this transformation, there
7339 -- may be visibility errors on the prefix. The safest is to
7340 -- treat the selected component as an error.
7342 if Error_Posted
(P
) then
7343 Set_Etype
(N
, Any_Type
);
7347 Analyze_Selected_Component
(N
);
7352 -- Remaining cases generate various error messages
7355 -- Format node as expanded name, to avoid cascaded errors
7357 -- If the limited_with transformation was applied earlier, restore
7358 -- source for proper error reporting.
7360 if not Comes_From_Source
(P
)
7361 and then Nkind
(P
) = N_Explicit_Dereference
7363 Rewrite
(P
, Prefix
(P
));
7364 P_Type
:= Etype
(P
);
7367 Change_Selected_Component_To_Expanded_Name
(N
);
7368 Set_Entity
(N
, Any_Id
);
7369 Set_Etype
(N
, Any_Type
);
7371 -- Issue error message, but avoid this if error issued already.
7372 -- Use identifier of prefix if one is available.
7374 if P_Name
= Any_Id
then
7377 -- It is not an error if the prefix is the current instance of
7378 -- type name, e.g. the expression of a type aspect, when it is
7379 -- analyzed for ASIS use.
7381 elsif Is_Entity_Name
(P
) and then Is_Current_Instance
(P
) then
7384 elsif Ekind
(P_Name
) = E_Void
then
7385 Premature_Usage
(P
);
7387 elsif Nkind
(P
) /= N_Attribute_Reference
then
7389 -- This may have been meant as a prefixed call to a primitive
7390 -- of an untagged type. If it is a function call check type of
7391 -- its first formal and add explanation.
7394 F
: constant Entity_Id
:=
7395 Current_Entity
(Selector_Name
(N
));
7398 and then Is_Overloadable
(F
)
7399 and then Present
(First_Entity
(F
))
7400 and then not Is_Tagged_Type
(Etype
(First_Entity
(F
)))
7403 ("prefixed call is only allowed for objects of a "
7404 & "tagged type", N
);
7408 Error_Msg_N
("invalid prefix in selected component&", P
);
7410 if Is_Access_Type
(P_Type
)
7411 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
7414 ("\dereference must not be of an incomplete type "
7415 & "(RM 3.10.1)", P
);
7419 Error_Msg_N
("invalid prefix in selected component", P
);
7423 -- Selector name is restricted in SPARK
7425 if Nkind
(N
) = N_Expanded_Name
7426 and then Restriction_Check_Required
(SPARK_05
)
7428 if Is_Subprogram
(P_Name
) then
7429 Check_SPARK_05_Restriction
7430 ("prefix of expanded name cannot be a subprogram", P
);
7431 elsif Ekind
(P_Name
) = E_Loop
then
7432 Check_SPARK_05_Restriction
7433 ("prefix of expanded name cannot be a loop statement", P
);
7438 -- If prefix is not the name of an entity, it must be an expression,
7439 -- whose type is appropriate for a record. This is determined by
7442 Analyze_Selected_Component
(N
);
7445 Analyze_Dimension
(N
);
7446 end Find_Selected_Component
;
7452 procedure Find_Type
(N
: Node_Id
) is
7462 elsif Nkind
(N
) = N_Attribute_Reference
then
7464 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7465 -- need to enforce that at this point, since the declaration of the
7466 -- tagged type in the prefix would have been flagged already.
7468 if Attribute_Name
(N
) = Name_Class
then
7469 Check_Restriction
(No_Dispatch
, N
);
7470 Find_Type
(Prefix
(N
));
7472 -- Propagate error from bad prefix
7474 if Etype
(Prefix
(N
)) = Any_Type
then
7475 Set_Entity
(N
, Any_Type
);
7476 Set_Etype
(N
, Any_Type
);
7480 T
:= Base_Type
(Entity
(Prefix
(N
)));
7482 -- Case where type is not known to be tagged. Its appearance in
7483 -- the prefix of the 'Class attribute indicates that the full view
7486 if not Is_Tagged_Type
(T
) then
7487 if Ekind
(T
) = E_Incomplete_Type
then
7489 -- It is legal to denote the class type of an incomplete
7490 -- type. The full type will have to be tagged, of course.
7491 -- In Ada 2005 this usage is declared obsolescent, so we
7492 -- warn accordingly. This usage is only legal if the type
7493 -- is completed in the current scope, and not for a limited
7496 if Ada_Version
>= Ada_2005
then
7498 -- Test whether the Available_View of a limited type view
7499 -- is tagged, since the limited view may not be marked as
7500 -- tagged if the type itself has an untagged incomplete
7501 -- type view in its package.
7503 if From_Limited_With
(T
)
7504 and then not Is_Tagged_Type
(Available_View
(T
))
7507 ("prefix of Class attribute must be tagged", N
);
7508 Set_Etype
(N
, Any_Type
);
7509 Set_Entity
(N
, Any_Type
);
7512 -- ??? This test is temporarily disabled (always
7513 -- False) because it causes an unwanted warning on
7514 -- GNAT sources (built with -gnatg, which includes
7515 -- Warn_On_Obsolescent_ Feature). Once this issue
7516 -- is cleared in the sources, it can be enabled.
7518 elsif Warn_On_Obsolescent_Feature
and then False then
7520 ("applying 'Class to an untagged incomplete type"
7521 & " is an obsolescent feature (RM J.11)?r?", N
);
7525 Set_Is_Tagged_Type
(T
);
7526 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7527 Make_Class_Wide_Type
(T
);
7528 Set_Entity
(N
, Class_Wide_Type
(T
));
7529 Set_Etype
(N
, Class_Wide_Type
(T
));
7531 elsif Ekind
(T
) = E_Private_Type
7532 and then not Is_Generic_Type
(T
)
7533 and then In_Private_Part
(Scope
(T
))
7535 -- The Class attribute can be applied to an untagged private
7536 -- type fulfilled by a tagged type prior to the full type
7537 -- declaration (but only within the parent package's private
7538 -- part). Create the class-wide type now and check that the
7539 -- full type is tagged later during its analysis. Note that
7540 -- we do not mark the private type as tagged, unlike the
7541 -- case of incomplete types, because the type must still
7542 -- appear untagged to outside units.
7544 if No
(Class_Wide_Type
(T
)) then
7545 Make_Class_Wide_Type
(T
);
7548 Set_Entity
(N
, Class_Wide_Type
(T
));
7549 Set_Etype
(N
, Class_Wide_Type
(T
));
7552 -- Should we introduce a type Any_Tagged and use Wrong_Type
7553 -- here, it would be a bit more consistent???
7556 ("tagged type required, found}",
7557 Prefix
(N
), First_Subtype
(T
));
7558 Set_Entity
(N
, Any_Type
);
7562 -- Case of tagged type
7565 if Is_Concurrent_Type
(T
) then
7566 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7568 -- Previous error. Create a class-wide type for the
7569 -- synchronized type itself, with minimal semantic
7570 -- attributes, to catch other errors in some ACATS tests.
7572 pragma Assert
(Serious_Errors_Detected
/= 0);
7573 Make_Class_Wide_Type
(T
);
7574 C
:= Class_Wide_Type
(T
);
7575 Set_First_Entity
(C
, First_Entity
(T
));
7578 C
:= Class_Wide_Type
7579 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7583 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7586 Set_Entity_With_Checks
(N
, C
);
7587 Generate_Reference
(C
, N
);
7591 -- Base attribute, not allowed in Ada 83
7593 elsif Attribute_Name
(N
) = Name_Base
then
7594 Error_Msg_Name_1
:= Name_Base
;
7595 Check_SPARK_05_Restriction
7596 ("attribute% is only allowed as prefix of another attribute", N
);
7598 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7600 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7603 Find_Type
(Prefix
(N
));
7604 Typ
:= Entity
(Prefix
(N
));
7606 if Ada_Version
>= Ada_95
7607 and then not Is_Scalar_Type
(Typ
)
7608 and then not Is_Generic_Type
(Typ
)
7611 ("prefix of Base attribute must be scalar type",
7614 elsif Warn_On_Redundant_Constructs
7615 and then Base_Type
(Typ
) = Typ
7617 Error_Msg_NE
-- CODEFIX
7618 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7621 T
:= Base_Type
(Typ
);
7623 -- Rewrite attribute reference with type itself (see similar
7624 -- processing in Analyze_Attribute, case Base). Preserve prefix
7625 -- if present, for other legality checks.
7627 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7629 Make_Expanded_Name
(Sloc
(N
),
7631 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7632 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7635 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7642 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7644 -- This is handled in Analyze_Attribute
7648 -- All other attributes are invalid in a subtype mark
7651 Error_Msg_N
("invalid attribute in subtype mark", N
);
7657 if Is_Entity_Name
(N
) then
7658 T_Name
:= Entity
(N
);
7660 Error_Msg_N
("subtype mark required in this context", N
);
7661 Set_Etype
(N
, Any_Type
);
7665 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7667 -- Undefined id. Make it into a valid type
7669 Set_Entity
(N
, Any_Type
);
7671 elsif not Is_Type
(T_Name
)
7672 and then T_Name
/= Standard_Void_Type
7674 Error_Msg_Sloc
:= Sloc
(T_Name
);
7675 Error_Msg_N
("subtype mark required in this context", N
);
7676 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7677 Set_Entity
(N
, Any_Type
);
7680 -- If the type is an incomplete type created to handle
7681 -- anonymous access components of a record type, then the
7682 -- incomplete type is the visible entity and subsequent
7683 -- references will point to it. Mark the original full
7684 -- type as referenced, to prevent spurious warnings.
7686 if Is_Incomplete_Type
(T_Name
)
7687 and then Present
(Full_View
(T_Name
))
7688 and then not Comes_From_Source
(T_Name
)
7690 Set_Referenced
(Full_View
(T_Name
));
7693 T_Name
:= Get_Full_View
(T_Name
);
7695 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7696 -- limited-with clauses
7698 if From_Limited_With
(T_Name
)
7699 and then Ekind
(T_Name
) in Incomplete_Kind
7700 and then Present
(Non_Limited_View
(T_Name
))
7701 and then Is_Interface
(Non_Limited_View
(T_Name
))
7703 T_Name
:= Non_Limited_View
(T_Name
);
7706 if In_Open_Scopes
(T_Name
) then
7707 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7709 -- In Ada 2005, a task name can be used in an access
7710 -- definition within its own body. It cannot be used
7711 -- in the discriminant part of the task declaration,
7712 -- nor anywhere else in the declaration because entries
7713 -- cannot have access parameters.
7715 if Ada_Version
>= Ada_2005
7716 and then Nkind
(Parent
(N
)) = N_Access_Definition
7718 Set_Entity
(N
, T_Name
);
7719 Set_Etype
(N
, T_Name
);
7721 if Has_Completion
(T_Name
) then
7726 ("task type cannot be used as type mark " &
7727 "within its own declaration", N
);
7732 ("task type cannot be used as type mark " &
7733 "within its own spec or body", N
);
7736 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7738 -- In Ada 2005, a protected name can be used in an access
7739 -- definition within its own body.
7741 if Ada_Version
>= Ada_2005
7742 and then Nkind
(Parent
(N
)) = N_Access_Definition
7744 Set_Entity
(N
, T_Name
);
7745 Set_Etype
(N
, T_Name
);
7750 ("protected type cannot be used as type mark " &
7751 "within its own spec or body", N
);
7755 Error_Msg_N
("type declaration cannot refer to itself", N
);
7758 Set_Etype
(N
, Any_Type
);
7759 Set_Entity
(N
, Any_Type
);
7760 Set_Error_Posted
(T_Name
);
7764 Set_Entity
(N
, T_Name
);
7765 Set_Etype
(N
, T_Name
);
7769 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7770 if Is_Fixed_Point_Type
(Etype
(N
)) then
7771 Check_Restriction
(No_Fixed_Point
, N
);
7772 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7773 Check_Restriction
(No_Floating_Point
, N
);
7776 -- A Ghost type must appear in a specific context
7778 if Is_Ghost_Entity
(Etype
(N
)) then
7779 Check_Ghost_Context
(Etype
(N
), N
);
7784 ------------------------------------
7785 -- Has_Implicit_Character_Literal --
7786 ------------------------------------
7788 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7790 Found
: Boolean := False;
7791 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7792 Priv_Id
: Entity_Id
:= Empty
;
7795 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7796 Priv_Id
:= First_Private_Entity
(P
);
7799 if P
= Standard_Standard
then
7800 Change_Selected_Component_To_Expanded_Name
(N
);
7801 Rewrite
(N
, Selector_Name
(N
));
7803 Set_Etype
(Original_Node
(N
), Standard_Character
);
7807 Id
:= First_Entity
(P
);
7808 while Present
(Id
) and then Id
/= Priv_Id
loop
7809 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7811 -- We replace the node with the literal itself, resolve as a
7812 -- character, and set the type correctly.
7815 Change_Selected_Component_To_Expanded_Name
(N
);
7816 Rewrite
(N
, Selector_Name
(N
));
7819 Set_Etype
(Original_Node
(N
), Id
);
7823 -- More than one type derived from Character in given scope.
7824 -- Collect all possible interpretations.
7826 Add_One_Interp
(N
, Id
, Id
);
7834 end Has_Implicit_Character_Literal
;
7836 ----------------------
7837 -- Has_Private_With --
7838 ----------------------
7840 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7841 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7845 Item
:= First
(Context_Items
(Comp_Unit
));
7846 while Present
(Item
) loop
7847 if Nkind
(Item
) = N_With_Clause
7848 and then Private_Present
(Item
)
7849 and then Entity
(Name
(Item
)) = E
7858 end Has_Private_With
;
7860 ---------------------------
7861 -- Has_Implicit_Operator --
7862 ---------------------------
7864 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7865 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7866 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7868 Priv_Id
: Entity_Id
:= Empty
;
7870 procedure Add_Implicit_Operator
7872 Op_Type
: Entity_Id
:= Empty
);
7873 -- Add implicit interpretation to node N, using the type for which a
7874 -- predefined operator exists. If the operator yields a boolean type,
7875 -- the Operand_Type is implicitly referenced by the operator, and a
7876 -- reference to it must be generated.
7878 ---------------------------
7879 -- Add_Implicit_Operator --
7880 ---------------------------
7882 procedure Add_Implicit_Operator
7884 Op_Type
: Entity_Id
:= Empty
)
7886 Predef_Op
: Entity_Id
;
7889 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7890 while Present
(Predef_Op
)
7891 and then Scope
(Predef_Op
) /= Standard_Standard
7893 Predef_Op
:= Homonym
(Predef_Op
);
7896 if Nkind
(N
) = N_Selected_Component
then
7897 Change_Selected_Component_To_Expanded_Name
(N
);
7900 -- If the context is an unanalyzed function call, determine whether
7901 -- a binary or unary interpretation is required.
7903 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7905 Is_Binary_Call
: constant Boolean :=
7907 (Next
(First
(Expressions
(Parent
(N
)))));
7908 Is_Binary_Op
: constant Boolean :=
7910 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7911 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7914 if Is_Binary_Call
then
7915 if Is_Binary_Op
then
7916 Add_One_Interp
(N
, Predef_Op
, T
);
7918 Add_One_Interp
(N
, Predef_Op2
, T
);
7922 if not Is_Binary_Op
then
7923 Add_One_Interp
(N
, Predef_Op
, T
);
7925 Add_One_Interp
(N
, Predef_Op2
, T
);
7931 Add_One_Interp
(N
, Predef_Op
, T
);
7933 -- For operators with unary and binary interpretations, if
7934 -- context is not a call, add both
7936 if Present
(Homonym
(Predef_Op
)) then
7937 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7941 -- The node is a reference to a predefined operator, and
7942 -- an implicit reference to the type of its operands.
7944 if Present
(Op_Type
) then
7945 Generate_Operator_Reference
(N
, Op_Type
);
7947 Generate_Operator_Reference
(N
, T
);
7949 end Add_Implicit_Operator
;
7951 -- Start of processing for Has_Implicit_Operator
7954 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7955 Priv_Id
:= First_Private_Entity
(P
);
7958 Id
:= First_Entity
(P
);
7962 -- Boolean operators: an implicit declaration exists if the scope
7963 -- contains a declaration for a derived Boolean type, or for an
7964 -- array of Boolean type.
7971 while Id
/= Priv_Id
loop
7972 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7973 Add_Implicit_Operator
(Id
);
7980 -- Equality: look for any non-limited type (result is Boolean)
7985 while Id
/= Priv_Id
loop
7987 and then not Is_Limited_Type
(Id
)
7988 and then Is_Base_Type
(Id
)
7990 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7997 -- Comparison operators: scalar type, or array of scalar
8004 while Id
/= Priv_Id
loop
8005 if (Is_Scalar_Type
(Id
)
8006 or else (Is_Array_Type
(Id
)
8007 and then Is_Scalar_Type
(Component_Type
(Id
))))
8008 and then Is_Base_Type
(Id
)
8010 Add_Implicit_Operator
(Standard_Boolean
, Id
);
8017 -- Arithmetic operators: any numeric type
8028 while Id
/= Priv_Id
loop
8029 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
8030 Add_Implicit_Operator
(Id
);
8037 -- Concatenation: any one-dimensional array type
8039 when Name_Op_Concat
=>
8040 while Id
/= Priv_Id
loop
8041 if Is_Array_Type
(Id
)
8042 and then Number_Dimensions
(Id
) = 1
8043 and then Is_Base_Type
(Id
)
8045 Add_Implicit_Operator
(Id
);
8052 -- What is the others condition here? Should we be using a
8053 -- subtype of Name_Id that would restrict to operators ???
8059 -- If we fall through, then we do not have an implicit operator
8062 end Has_Implicit_Operator
;
8064 -----------------------------------
8065 -- Has_Loop_In_Inner_Open_Scopes --
8066 -----------------------------------
8068 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
8070 -- Several scope stacks are maintained by Scope_Stack. The base of the
8071 -- currently active scope stack is denoted by the Is_Active_Stack_Base
8072 -- flag in the scope stack entry. Note that the scope stacks used to
8073 -- simply be delimited implicitly by the presence of Standard_Standard
8074 -- at their base, but there now are cases where this is not sufficient
8075 -- because Standard_Standard actually may appear in the middle of the
8076 -- active set of scopes.
8078 for J
in reverse 0 .. Scope_Stack
.Last
loop
8080 -- S was reached without seing a loop scope first
8082 if Scope_Stack
.Table
(J
).Entity
= S
then
8085 -- S was not yet reached, so it contains at least one inner loop
8087 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
8091 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
8092 -- cases where Standard_Standard appears in the middle of the active
8093 -- set of scopes. This affects the declaration and overriding of
8094 -- private inherited operations in instantiations of generic child
8097 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
8100 raise Program_Error
; -- unreachable
8101 end Has_Loop_In_Inner_Open_Scopes
;
8103 --------------------
8104 -- In_Open_Scopes --
8105 --------------------
8107 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
8109 -- Several scope stacks are maintained by Scope_Stack. The base of the
8110 -- currently active scope stack is denoted by the Is_Active_Stack_Base
8111 -- flag in the scope stack entry. Note that the scope stacks used to
8112 -- simply be delimited implicitly by the presence of Standard_Standard
8113 -- at their base, but there now are cases where this is not sufficient
8114 -- because Standard_Standard actually may appear in the middle of the
8115 -- active set of scopes.
8117 for J
in reverse 0 .. Scope_Stack
.Last
loop
8118 if Scope_Stack
.Table
(J
).Entity
= S
then
8122 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
8123 -- cases where Standard_Standard appears in the middle of the active
8124 -- set of scopes. This affects the declaration and overriding of
8125 -- private inherited operations in instantiations of generic child
8128 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
8134 -----------------------------
8135 -- Inherit_Renamed_Profile --
8136 -----------------------------
8138 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
8145 if Ekind
(Old_S
) = E_Operator
then
8146 New_F
:= First_Formal
(New_S
);
8148 while Present
(New_F
) loop
8149 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
8150 Next_Formal
(New_F
);
8153 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
8156 New_F
:= First_Formal
(New_S
);
8157 Old_F
:= First_Formal
(Old_S
);
8159 while Present
(New_F
) loop
8160 New_T
:= Etype
(New_F
);
8161 Old_T
:= Etype
(Old_F
);
8163 -- If the new type is a renaming of the old one, as is the case
8164 -- for actuals in instances, retain its name, to simplify later
8167 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
8168 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
8169 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
8173 Set_Etype
(New_F
, Old_T
);
8176 Next_Formal
(New_F
);
8177 Next_Formal
(Old_F
);
8180 pragma Assert
(No
(Old_F
));
8182 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
8183 Set_Etype
(New_S
, Etype
(Old_S
));
8186 end Inherit_Renamed_Profile
;
8192 procedure Initialize
is
8197 -------------------------
8198 -- Install_Use_Clauses --
8199 -------------------------
8201 procedure Install_Use_Clauses
8203 Force_Installation
: Boolean := False)
8209 while Present
(U
) loop
8211 -- Case of USE package
8213 if Nkind
(U
) = N_Use_Package_Clause
then
8214 Use_One_Package
(U
, Name
(U
), True);
8219 Use_One_Type
(Subtype_Mark
(U
), Force
=> Force_Installation
);
8223 Next_Use_Clause
(U
);
8225 end Install_Use_Clauses
;
8227 -------------------------------------
8228 -- Is_Appropriate_For_Entry_Prefix --
8229 -------------------------------------
8231 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
8232 P_Type
: Entity_Id
:= T
;
8235 if Is_Access_Type
(P_Type
) then
8236 P_Type
:= Designated_Type
(P_Type
);
8239 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
8240 end Is_Appropriate_For_Entry_Prefix
;
8242 -------------------------------
8243 -- Is_Appropriate_For_Record --
8244 -------------------------------
8246 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
8248 function Has_Components
(T1
: Entity_Id
) return Boolean;
8249 -- Determine if given type has components (i.e. is either a record
8250 -- type or a type that has discriminants).
8252 --------------------
8253 -- Has_Components --
8254 --------------------
8256 function Has_Components
(T1
: Entity_Id
) return Boolean is
8258 return Is_Record_Type
(T1
)
8259 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
8260 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
8261 or else (Is_Incomplete_Type
(T1
)
8262 and then From_Limited_With
(T1
)
8263 and then Present
(Non_Limited_View
(T1
))
8264 and then Is_Record_Type
8265 (Get_Full_View
(Non_Limited_View
(T1
))));
8268 -- Start of processing for Is_Appropriate_For_Record
8273 and then (Has_Components
(T
)
8274 or else (Is_Access_Type
(T
)
8275 and then Has_Components
(Designated_Type
(T
))));
8276 end Is_Appropriate_For_Record
;
8278 ----------------------
8279 -- Mark_Use_Clauses --
8280 ----------------------
8282 procedure Mark_Use_Clauses
(Id
: Node_Or_Entity_Id
) is
8283 procedure Mark_Parameters
(Call
: Entity_Id
);
8284 -- Perform use_type_clause marking for all parameters in a subprogram
8285 -- or operator call.
8287 procedure Mark_Use_Package
(Pak
: Entity_Id
);
8288 -- Move up the Prev_Use_Clause chain for packages denoted by Pak -
8289 -- marking each clause in the chain as effective in the process.
8291 procedure Mark_Use_Type
(E
: Entity_Id
);
8292 -- Similar to Do_Use_Package_Marking except we move up the
8293 -- Prev_Use_Clause chain for the type denoted by E.
8295 ---------------------
8296 -- Mark_Parameters --
8297 ---------------------
8299 procedure Mark_Parameters
(Call
: Entity_Id
) is
8303 -- Move through all of the formals
8305 Curr
:= First_Formal
(Call
);
8306 while Present
(Curr
) loop
8307 Mark_Use_Type
(Curr
);
8309 Curr
:= Next_Formal
(Curr
);
8312 -- Handle the return type
8314 Mark_Use_Type
(Call
);
8315 end Mark_Parameters
;
8317 ----------------------
8318 -- Mark_Use_Package --
8319 ----------------------
8321 procedure Mark_Use_Package
(Pak
: Entity_Id
) is
8325 -- Ignore cases where the scope of the type is not a package (e.g.
8326 -- Standard_Standard).
8328 if Ekind
(Pak
) /= E_Package
then
8332 Curr
:= Current_Use_Clause
(Pak
);
8333 while Present
(Curr
)
8334 and then not Is_Effective_Use_Clause
(Curr
)
8336 -- We need to mark the previous use clauses as effective, but
8337 -- each use clause may in turn render other use_package_clauses
8338 -- effective. Additionally, it is possible to have a parent
8339 -- package renamed as a child of itself so we must check the
8340 -- prefix entity is not the same as the package we are marking.
8342 if Nkind
(Name
(Curr
)) /= N_Identifier
8343 and then Present
(Prefix
(Name
(Curr
)))
8344 and then Entity
(Prefix
(Name
(Curr
))) /= Pak
8346 Mark_Use_Package
(Entity
(Prefix
(Name
(Curr
))));
8348 -- It is also possible to have a child package without a prefix
8349 -- that relies on a previous use_package_clause.
8351 elsif Nkind
(Name
(Curr
)) = N_Identifier
8352 and then Is_Child_Unit
(Entity
(Name
(Curr
)))
8354 Mark_Use_Package
(Scope
(Entity
(Name
(Curr
))));
8357 -- Mark the use_package_clause as effective and move up the chain
8359 Set_Is_Effective_Use_Clause
(Curr
);
8361 Curr
:= Prev_Use_Clause
(Curr
);
8363 end Mark_Use_Package
;
8369 procedure Mark_Use_Type
(E
: Entity_Id
) is
8374 -- Ignore void types and unresolved string literals and primitives
8376 if Nkind
(E
) = N_String_Literal
8377 or else Nkind
(Etype
(E
)) not in N_Entity
8378 or else not Is_Type
(Etype
(E
))
8383 -- Primitives with class-wide operands might additionally render
8384 -- their base type's use_clauses effective - so do a recursive check
8387 Base
:= Base_Type
(Etype
(E
));
8389 if Ekind
(Base
) = E_Class_Wide_Type
then
8390 Mark_Use_Type
(Base
);
8393 -- The package containing the type or operator function being used
8394 -- may be in use as well, so mark any use_package_clauses for it as
8395 -- effective. There are also additional sanity checks performed here
8396 -- for ignoring previous errors.
8398 Mark_Use_Package
(Scope
(Base
));
8400 if Nkind
(E
) in N_Op
8401 and then Present
(Entity
(E
))
8402 and then Present
(Scope
(Entity
(E
)))
8404 Mark_Use_Package
(Scope
(Entity
(E
)));
8407 Curr
:= Current_Use_Clause
(Base
);
8408 while Present
(Curr
)
8409 and then not Is_Effective_Use_Clause
(Curr
)
8411 -- Current use_type_clause may render other use_package_clauses
8414 if Nkind
(Subtype_Mark
(Curr
)) /= N_Identifier
8415 and then Present
(Prefix
(Subtype_Mark
(Curr
)))
8417 Mark_Use_Package
(Entity
(Prefix
(Subtype_Mark
(Curr
))));
8420 -- Mark the use_type_clause as effective and move up the chain
8422 Set_Is_Effective_Use_Clause
(Curr
);
8424 Curr
:= Prev_Use_Clause
(Curr
);
8428 -- Start of processing for Mark_Use_Clauses
8431 -- Use clauses in and of themselves do not count as a "use" of a
8434 if Nkind_In
(Parent
(Id
), N_Use_Package_Clause
, N_Use_Type_Clause
) then
8440 if Nkind
(Id
) in N_Entity
then
8442 -- Mark the entity's package
8444 if Is_Potentially_Use_Visible
(Id
) then
8445 Mark_Use_Package
(Scope
(Id
));
8448 -- Mark enumeration literals
8450 if Ekind
(Id
) = E_Enumeration_Literal
then
8455 elsif (Ekind
(Id
) in Overloadable_Kind
8456 or else Ekind_In
(Id
, E_Generic_Function
,
8457 E_Generic_Procedure
))
8458 and then (Is_Potentially_Use_Visible
(Id
)
8459 or else Is_Intrinsic_Subprogram
(Id
)
8460 or else (Ekind_In
(Id
, E_Function
, E_Procedure
)
8461 and then Is_Generic_Actual_Subprogram
(Id
)))
8463 Mark_Parameters
(Id
);
8471 if Nkind
(Id
) in N_Op
then
8473 -- At this point the left operand may not be resolved if we are
8474 -- encountering multiple operators next to eachother in an
8477 if Nkind
(Id
) in N_Binary_Op
8478 and then not (Nkind
(Left_Opnd
(Id
)) in N_Op
)
8480 Mark_Use_Type
(Left_Opnd
(Id
));
8483 Mark_Use_Type
(Right_Opnd
(Id
));
8486 -- Mark entity identifiers
8488 elsif Nkind
(Id
) in N_Has_Entity
8489 and then (Is_Potentially_Use_Visible
(Entity
(Id
))
8490 or else (Is_Generic_Instance
(Entity
(Id
))
8491 and then Is_Immediately_Visible
(Entity
(Id
))))
8493 -- Ignore fully qualified names as they do not count as a "use" of
8496 if Nkind_In
(Id
, N_Identifier
, N_Operator_Symbol
)
8497 or else (Present
(Prefix
(Id
))
8498 and then Scope
(Entity
(Id
)) /= Entity
(Prefix
(Id
)))
8500 Mark_Use_Clauses
(Entity
(Id
));
8504 end Mark_Use_Clauses
;
8506 --------------------------------
8507 -- Most_Descendant_Use_Clause --
8508 --------------------------------
8510 function Most_Descendant_Use_Clause
8511 (Clause1
: Entity_Id
;
8512 Clause2
: Entity_Id
) return Entity_Id
8514 Scope1
, Scope2
: Entity_Id
;
8517 if Clause1
= Clause2
then
8521 -- We determine which one is the most descendant by the scope distance
8522 -- to the ultimate parent unit.
8524 Scope1
:= Entity_Of_Unit
(Unit
(Parent
(Clause1
)));
8525 Scope2
:= Entity_Of_Unit
(Unit
(Parent
(Clause2
)));
8526 while Scope1
/= Standard_Standard
8527 and then Scope2
/= Standard_Standard
8529 Scope1
:= Scope
(Scope1
);
8530 Scope2
:= Scope
(Scope2
);
8532 if not Present
(Scope1
) then
8534 elsif not Present
(Scope2
) then
8539 if Scope1
= Standard_Standard
then
8544 end Most_Descendant_Use_Clause
;
8550 procedure Pop_Scope
is
8551 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8552 S
: constant Entity_Id
:= SST
.Entity
;
8555 if Debug_Flag_E
then
8559 -- Set Default_Storage_Pool field of the library unit if necessary
8561 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8563 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8566 Aux
: constant Node_Id
:=
8567 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8569 if No
(Default_Storage_Pool
(Aux
)) then
8570 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8575 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8576 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8577 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8578 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8579 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8580 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8581 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8582 Default_SSO
:= SST
.Save_Default_SSO
;
8583 Uneval_Old
:= SST
.Save_Uneval_Old
;
8585 if Debug_Flag_W
then
8586 Write_Str
("<-- exiting scope: ");
8587 Write_Name
(Chars
(Current_Scope
));
8588 Write_Str
(", Depth=");
8589 Write_Int
(Int
(Scope_Stack
.Last
));
8593 End_Use_Clauses
(SST
.First_Use_Clause
);
8595 -- If the actions to be wrapped are still there they will get lost
8596 -- causing incomplete code to be generated. It is better to abort in
8597 -- this case (and we do the abort even with assertions off since the
8598 -- penalty is incorrect code generation).
8600 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8601 raise Program_Error;
8604 -- Free last subprogram name if allocated, and pop scope
8606 Free (SST.Last_Subprogram_Name);
8607 Scope_Stack.Decrement_Last;
8614 procedure Push_Scope (S : Entity_Id) is
8615 E : constant Entity_Id := Scope (S);
8618 if Ekind (S) = E_Void then
8621 -- Set scope depth if not a non-concurrent type, and we have not yet set
8622 -- the scope depth. This means that we have the first occurrence of the
8623 -- scope, and this is where the depth is set.
8625 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8626 and then not Scope_Depth_Set (S)
8628 if S = Standard_Standard then
8629 Set_Scope_Depth_Value (S, Uint_0);
8631 elsif Is_Child_Unit (S) then
8632 Set_Scope_Depth_Value (S, Uint_1);
8634 elsif not Is_Record_Type (Current_Scope) then
8635 if Ekind (S) = E_Loop then
8636 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8638 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8643 Scope_Stack.Increment_Last;
8646 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8650 SST.Save_Scope_Suppress := Scope_Suppress;
8651 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8652 SST.Save_Check_Policy_List := Check_Policy_List;
8653 SST.Save_Default_Storage_Pool := Default_Pool;
8654 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8655 SST.Save_SPARK_Mode := SPARK_Mode;
8656 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8657 SST.Save_Default_SSO := Default_SSO;
8658 SST.Save_Uneval_Old := Uneval_Old;
8660 -- Each new scope pushed onto the scope stack inherits the component
8661 -- alignment of the previous scope. This emulates the "visibility"
8662 -- semantics of pragma Component_Alignment.
8664 if Scope_Stack.Last > Scope_Stack.First then
8665 SST.Component_Alignment_Default :=
8667 (Scope_Stack.Last - 1). Component_Alignment_Default;
8669 -- Otherwise, this is the first scope being pushed on the scope
8670 -- stack. Inherit the component alignment from the configuration
8671 -- form of pragma Component_Alignment (if any).
8674 SST.Component_Alignment_Default :=
8675 Configuration_Component_Alignment;
8678 SST.Last_Subprogram_Name := null;
8679 SST.Is_Transient := False;
8680 SST.Node_To_Be_Wrapped := Empty;
8681 SST.Pending_Freeze_Actions := No_List;
8682 SST.Actions_To_Be_Wrapped := (others => No_List);
8683 SST.First_Use_Clause := Empty;
8684 SST.Is_Active_Stack_Base := False;
8685 SST.Previous_Visibility := False;
8686 SST.Locked_Shared_Objects := No_Elist;
8689 if Debug_Flag_W then
8690 Write_Str ("--> new scope: ");
8691 Write_Name (Chars (Current_Scope));
8692 Write_Str (", Id=");
8693 Write_Int (Int (Current_Scope));
8694 Write_Str (", Depth=");
8695 Write_Int (Int (Scope_Stack.Last));
8699 -- Deal with copying flags from the previous scope to this one. This is
8700 -- not necessary if either scope is standard, or if the new scope is a
8703 if S /= Standard_Standard
8704 and then Scope (S) /= Standard_Standard
8705 and then not Is_Child_Unit (S)
8707 if Nkind (E) not in N_Entity then
8711 -- Copy categorization flags from Scope (S) to S, this is not done
8712 -- when Scope (S) is Standard_Standard since propagation is from
8713 -- library unit entity inwards. Copy other relevant attributes as
8714 -- well (Discard_Names in particular).
8716 -- We only propagate inwards for library level entities,
8717 -- inner level subprograms do not inherit the categorization.
8719 if Is_Library_Level_Entity (S) then
8720 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8721 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8722 Set_Discard_Names (S, Discard_Names (E));
8723 Set_Suppress_Value_Tracking_On_Call
8724 (S, Suppress_Value_Tracking_On_Call (E));
8725 Set_Categorization_From_Scope (E => S, Scop => E);
8729 if Is_Child_Unit (S)
8730 and then Present (E)
8731 and then Ekind_In (E, E_Package, E_Generic_Package)
8733 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8736 Aux : constant Node_Id :=
8737 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8739 if Present (Default_Storage_Pool (Aux)) then
8740 Default_Pool := Default_Storage_Pool (Aux);
8746 ---------------------
8747 -- Premature_Usage --
8748 ---------------------
8750 procedure Premature_Usage (N : Node_Id) is
8751 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8752 E : Entity_Id := Entity (N);
8755 -- Within an instance, the analysis of the actual for a formal object
8756 -- does not see the name of the object itself. This is significant only
8757 -- if the object is an aggregate, where its analysis does not do any
8758 -- name resolution on component associations. (see 4717-008). In such a
8759 -- case, look for the visible homonym on the chain.
8761 if In_Instance and then Present (Homonym (E)) then
8763 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8769 Set_Etype (N, Etype (E));
8774 if Kind = N_Component_Declaration then
8776 ("component&! cannot be used before end of record declaration", N);
8778 elsif Kind = N_Parameter_Specification then
8780 ("formal parameter&! cannot be used before end of specification",
8783 elsif Kind = N_Discriminant_Specification then
8785 ("discriminant&! cannot be used before end of discriminant part",
8788 elsif Kind = N_Procedure_Specification
8789 or else Kind = N_Function_Specification
8792 ("subprogram&! cannot be used before end of its declaration",
8795 elsif Kind = N_Full_Type_Declaration then
8797 ("type& cannot be used before end of its declaration!", N);
8801 ("object& cannot be used before end of its declaration!", N);
8803 -- If the premature reference appears as the expression in its own
8804 -- declaration, rewrite it to prevent compiler loops in subsequent
8805 -- uses of this mangled declaration in address clauses.
8807 if Nkind (Parent (N)) = N_Object_Declaration then
8808 Set_Entity (N, Any_Id);
8811 end Premature_Usage;
8813 ------------------------
8814 -- Present_System_Aux --
8815 ------------------------
8817 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8819 Aux_Name : Unit_Name_Type;
8820 Unum : Unit_Number_Type;
8825 function Find_System (C_Unit : Node_Id) return Entity_Id;
8826 -- Scan context clause of compilation unit to find with_clause
8833 function Find_System (C_Unit : Node_Id) return Entity_Id is
8834 With_Clause : Node_Id;
8837 With_Clause := First (Context_Items (C_Unit));
8838 while Present (With_Clause) loop
8839 if (Nkind (With_Clause) = N_With_Clause
8840 and then Chars (Name (With_Clause)) = Name_System)
8841 and then Comes_From_Source (With_Clause)
8852 -- Start of processing for Present_System_Aux
8855 -- The child unit may have been loaded and analyzed already
8857 if Present (System_Aux_Id) then
8860 -- If no previous pragma for System.Aux, nothing to load
8862 elsif No (System_Extend_Unit) then
8865 -- Use the unit name given in the pragma to retrieve the unit.
8866 -- Verify that System itself appears in the context clause of the
8867 -- current compilation. If System is not present, an error will
8868 -- have been reported already.
8871 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8873 The_Unit := Unit (Cunit (Current_Sem_Unit));
8877 (Nkind (The_Unit) = N_Package_Body
8878 or else (Nkind (The_Unit) = N_Subprogram_Body
8879 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8881 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8884 if No (With_Sys) and then Present (N) then
8886 -- If we are compiling a subunit, we need to examine its
8887 -- context as well (Current_Sem_Unit is the parent unit);
8889 The_Unit := Parent (N);
8890 while Nkind (The_Unit) /= N_Compilation_Unit loop
8891 The_Unit := Parent (The_Unit);
8894 if Nkind (Unit (The_Unit)) = N_Subunit then
8895 With_Sys := Find_System (The_Unit);
8899 if No (With_Sys) then
8903 Loc := Sloc (With_Sys);
8904 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8905 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8906 Name_Buffer (1 .. 7) := "system.";
8907 Name_Buffer (Name_Len + 8) := '%';
8908 Name_Buffer (Name_Len + 9) := 's
';
8909 Name_Len := Name_Len + 9;
8910 Aux_Name := Name_Find;
8914 (Load_Name => Aux_Name,
8917 Error_Node => With_Sys);
8919 if Unum /= No_Unit then
8920 Semantics (Cunit (Unum));
8922 Defining_Entity (Specification (Unit (Cunit (Unum))));
8925 Make_With_Clause (Loc,
8927 Make_Expanded_Name (Loc,
8928 Chars => Chars (System_Aux_Id),
8929 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8930 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8932 Set_Entity (Name (Withn), System_Aux_Id);
8934 Set_Library_Unit (Withn, Cunit (Unum));
8935 Set_Corresponding_Spec (Withn, System_Aux_Id);
8936 Set_First_Name (Withn, True);
8937 Set_Implicit_With (Withn, True);
8939 Insert_After (With_Sys, Withn);
8940 Mark_Rewrite_Insertion (Withn);
8941 Set_Context_Installed (Withn);
8945 -- Here if unit load failed
8948 Error_Msg_Name_1 := Name_System;
8949 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8951 ("extension package `%.%` does not exist",
8952 Opt.System_Extend_Unit);
8956 end Present_System_Aux;
8958 -------------------------
8959 -- Restore_Scope_Stack --
8960 -------------------------
8962 procedure Restore_Scope_Stack
8964 Handle_Use : Boolean := True)
8966 SS_Last : constant Int := Scope_Stack.Last;
8970 -- Restore visibility of previous scope stack, if any, using the list
8971 -- we saved (we use Remove, since this list will not be used again).
8974 Elmt := Last_Elmt (List);
8975 exit when Elmt = No_Elmt;
8976 Set_Is_Immediately_Visible (Node (Elmt));
8977 Remove_Last_Elmt (List);
8980 -- Restore use clauses
8982 if SS_Last >= Scope_Stack.First
8983 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8987 (Scope_Stack.Table (SS_Last).First_Use_Clause,
8988 Force_Installation => True);
8990 end Restore_Scope_Stack;
8992 ----------------------
8993 -- Save_Scope_Stack --
8994 ----------------------
8996 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8997 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8998 -- from immediate visibility entities and Restore_Scope_Stack took care
8999 -- of restoring their visibility analyzing the context of each entity. The
9000 -- problem of such approach is that it was fragile and caused unexpected
9001 -- visibility problems, and indeed one test was found where there was a
9004 -- Furthermore, the following experiment was carried out:
9006 -- - Save_Scope_Stack was modified to store in an Elist1 all those
9007 -- entities whose attribute Is_Immediately_Visible is modified
9008 -- from True to False.
9010 -- - Restore_Scope_Stack was modified to store in another Elist2
9011 -- all the entities whose attribute Is_Immediately_Visible is
9012 -- modified from False to True.
9014 -- - Extra code was added to verify that all the elements of Elist1
9015 -- are found in Elist2
9017 -- This test shows that there may be more occurrences of this problem which
9018 -- have not yet been detected. As a result, we replaced that approach by
9019 -- the current one in which Save_Scope_Stack returns the list of entities
9020 -- whose visibility is changed, and that list is passed to Restore_Scope_
9021 -- Stack to undo that change. This approach is simpler and safer, although
9022 -- it consumes more memory.
9024 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
9025 Result : constant Elist_Id := New_Elmt_List;
9028 SS_Last : constant Int := Scope_Stack.Last;
9030 procedure Remove_From_Visibility (E : Entity_Id);
9031 -- If E is immediately visible then append it to the result and remove
9032 -- it temporarily from visibility.
9034 ----------------------------
9035 -- Remove_From_Visibility --
9036 ----------------------------
9038 procedure Remove_From_Visibility (E : Entity_Id) is
9040 if Is_Immediately_Visible (E) then
9041 Append_Elmt (E, Result);
9042 Set_Is_Immediately_Visible (E, False);
9044 end Remove_From_Visibility;
9046 -- Start of processing for Save_Scope_Stack
9049 if SS_Last >= Scope_Stack.First
9050 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
9053 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
9056 -- If the call is from within a compilation unit, as when called from
9057 -- Rtsfind, make current entries in scope stack invisible while we
9058 -- analyze the new unit.
9060 for J in reverse 0 .. SS_Last loop
9061 exit when Scope_Stack.Table (J).Entity = Standard_Standard
9062 or else No (Scope_Stack.Table (J).Entity);
9064 S := Scope_Stack.Table (J).Entity;
9066 Remove_From_Visibility (S);
9068 E := First_Entity (S);
9069 while Present (E) loop
9070 Remove_From_Visibility (E);
9078 end Save_Scope_Stack;
9084 procedure Set_Use (L : List_Id) is
9090 while Present (Decl) loop
9091 if Nkind (Decl) = N_Use_Package_Clause then
9092 Chain_Use_Clause (Decl);
9093 Use_One_Package (Decl, Name (Decl));
9095 elsif Nkind (Decl) = N_Use_Type_Clause then
9096 Chain_Use_Clause (Decl);
9097 Use_One_Type (Subtype_Mark (Decl));
9106 -----------------------------
9107 -- Update_Use_Clause_Chain --
9108 -----------------------------
9110 procedure Update_Use_Clause_Chain is
9111 procedure Update_Chain_In_Scope (Level : Int);
9112 -- Iterate through one level in the scope stack verifying each use-type
9113 -- clause within said level is used then reset the Current_Use_Clause
9114 -- to a redundant use clause outside of the current ending scope if such
9117 ---------------------------
9118 -- Update_Chain_In_Scope --
9119 ---------------------------
9121 procedure Update_Chain_In_Scope (Level : Int) is
9126 -- Loop through all use clauses within the scope dictated by Level
9128 Curr := Scope_Stack.Table (Level).First_Use_Clause;
9129 while Present (Curr) loop
9131 -- Retrieve the subtype mark or name within the current current
9134 if Nkind (Curr) = N_Use_Type_Clause then
9135 N := Subtype_Mark (Curr);
9140 -- If warnings for unreferenced entities are enabled and the
9141 -- current use clause has not been marked effective.
9143 if Check_Unreferenced
9144 and then Comes_From_Source (Curr)
9145 and then not Is_Effective_Use_Clause (Curr)
9146 and then not In_Instance
9147 and then not In_Inlined_Body
9149 -- We are dealing with a potentially unused use_package_clause
9151 if Nkind (Curr) = N_Use_Package_Clause then
9153 -- Renamings and formal subprograms may cause the associated
9154 -- to be marked as effective instead of the original.
9156 if not (Present (Associated_Node (N))
9159 (Associated_Node (N)))
9160 and then Is_Effective_Use_Clause
9162 (Associated_Node (N))))
9164 Error_Msg_Node_1 := Entity (N);
9166 ("use clause for package & has no effect?u?",
9170 -- We are dealing with an unused use_type_clause
9173 Error_Msg_Node_1 := Etype (N);
9175 ("use clause for } has no effect?u?", Curr, Etype (N));
9179 -- Verify that we haven't already processed a redundant
9180 -- use_type_clause within the same scope before we move the
9181 -- current use clause up to a previous one for type T.
9183 if Present (Prev_Use_Clause (Curr)) then
9184 Set_Current_Use_Clause (Entity (N), Prev_Use_Clause (Curr));
9187 Curr := Next_Use_Clause (Curr);
9189 end Update_Chain_In_Scope;
9191 -- Start of processing for Update_Use_Clause_Chain
9194 Update_Chain_In_Scope (Scope_Stack.Last);
9196 -- Deal with use clauses within the context area if the current
9197 -- scope is a compilation unit.
9199 if Is_Compilation_Unit (Current_Scope)
9200 and then Sloc (Scope_Stack.Table
9201 (Scope_Stack.Last - 1).Entity) = Standard_Location
9203 Update_Chain_In_Scope (Scope_Stack.Last - 1);
9205 end Update_Use_Clause_Chain;
9207 ---------------------
9208 -- Use_One_Package --
9209 ---------------------
9211 procedure Use_One_Package
9213 Pack_Name : Entity_Id := Empty;
9214 Force : Boolean := False)
9216 procedure Note_Redundant_Use (Clause : Node_Id);
9217 -- Mark the name in a use clause as redundant if the corresponding
9218 -- entity is already use-visible. Emit a warning if the use clause comes
9219 -- from source and the proper warnings are enabled.
9221 ------------------------
9222 -- Note_Redundant_Use --
9223 ------------------------
9225 procedure Note_Redundant_Use (Clause : Node_Id) is
9226 Decl : constant Node_Id := Parent (Clause);
9227 Pack_Name : constant Entity_Id := Entity (Clause);
9229 Cur_Use : Node_Id := Current_Use_Clause (Pack_Name);
9230 Prev_Use : Node_Id := Empty;
9231 Redundant : Node_Id := Empty;
9232 -- The Use_Clause which is actually redundant. In the simplest case
9233 -- it is Pack itself, but when we compile a body we install its
9234 -- context before that of its spec, in which case it is the
9235 -- use_clause in the spec that will appear to be redundant, and we
9236 -- want the warning to be placed on the body. Similar complications
9237 -- appear when the redundancy is between a child unit and one of its
9241 -- Could be renamed...
9243 if No (Cur_Use) then
9244 Cur_Use := Current_Use_Clause (Renamed_Entity (Pack_Name));
9247 Set_Redundant_Use (Clause, True);
9249 if not Comes_From_Source (Clause)
9251 or else not Warn_On_Redundant_Constructs
9256 if not Is_Compilation_Unit (Current_Scope) then
9258 -- If the use_clause is in an inner scope, it is made redundant by
9259 -- some clause in the current context, with one exception: If we
9260 -- are compiling a nested package body, and the use_clause comes
9261 -- from then corresponding spec, the clause is not necessarily
9262 -- fully redundant, so we should not warn. If a warning was
9263 -- warranted, it would have been given when the spec was
9266 if Nkind (Parent (Decl)) = N_Package_Specification then
9268 Package_Spec_Entity : constant Entity_Id :=
9269 Defining_Unit_Name (Parent (Decl));
9271 if In_Package_Body (Package_Spec_Entity) then
9277 Redundant := Clause;
9278 Prev_Use := Cur_Use;
9280 elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
9282 Cur_Unit : constant Unit_Number_Type :=
9283 Get_Source_Unit (Cur_Use);
9284 New_Unit : constant Unit_Number_Type :=
9285 Get_Source_Unit (Clause);
9290 if Cur_Unit = New_Unit then
9292 -- Redundant clause in same body
9294 Redundant := Clause;
9295 Prev_Use := Cur_Use;
9297 elsif Cur_Unit = Current_Sem_Unit then
9299 -- If the new clause is not in the current unit it has been
9300 -- analyzed first, and it makes the other one redundant.
9301 -- However, if the new clause appears in a subunit, Cur_Unit
9302 -- is still the parent, and in that case the redundant one
9303 -- is the one appearing in the subunit.
9305 if Nkind (Unit (Cunit (New_Unit))) = N_Subunit then
9306 Redundant := Clause;
9307 Prev_Use := Cur_Use;
9309 -- Most common case: redundant clause in body, original
9310 -- clause in spec. Current scope is spec entity.
9312 elsif Current_Scope = Cunit_Entity (Current_Sem_Unit) then
9313 Redundant := Cur_Use;
9317 -- The new clause may appear in an unrelated unit, when
9318 -- the parents of a generic are being installed prior to
9319 -- instantiation. In this case there must be no warning.
9320 -- We detect this case by checking whether the current
9321 -- top of the stack is related to the current
9324 Scop := Current_Scope;
9325 while Present (Scop)
9326 and then Scop /= Standard_Standard
9328 if Is_Compilation_Unit (Scop)
9329 and then not Is_Child_Unit (Scop)
9333 elsif Scop = Cunit_Entity (Current_Sem_Unit) then
9337 Scop := Scope (Scop);
9340 Redundant := Cur_Use;
9344 elsif New_Unit = Current_Sem_Unit then
9345 Redundant := Clause;
9346 Prev_Use := Cur_Use;
9349 -- Neither is the current unit, so they appear in parent or
9350 -- sibling units. Warning will be emitted elsewhere.
9356 elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Declaration
9357 and then Present (Parent_Spec (Unit (Cunit (Current_Sem_Unit))))
9359 -- Use_clause is in child unit of current unit, and the child unit
9360 -- appears in the context of the body of the parent, so it has
9361 -- been installed first, even though it is the redundant one.
9362 -- Depending on their placement in the context, the visible or the
9363 -- private parts of the two units, either might appear as
9364 -- redundant, but the message has to be on the current unit.
9366 if Get_Source_Unit (Cur_Use) = Current_Sem_Unit then
9367 Redundant := Cur_Use;
9370 Redundant := Clause;
9371 Prev_Use := Cur_Use;
9374 -- If the new use clause appears in the private part of a parent
9375 -- unit it may appear to be redundant w.r.t. a use clause in a
9376 -- child unit, but the previous use clause was needed in the
9377 -- visible part of the child, and no warning should be emitted.
9379 if Nkind (Parent (Decl)) = N_Package_Specification
9380 and then List_Containing (Decl) =
9381 Private_Declarations (Parent (Decl))
9384 Par : constant Entity_Id := Defining_Entity (Parent (Decl));
9385 Spec : constant Node_Id :=
9386 Specification (Unit (Cunit (Current_Sem_Unit)));
9389 if Is_Compilation_Unit (Par)
9390 and then Par /= Cunit_Entity (Current_Sem_Unit)
9391 and then Parent (Cur_Use) = Spec
9392 and then List_Containing (Cur_Use) =
9393 Visible_Declarations (Spec)
9400 -- Finally, if the current use clause is in the context then the
9401 -- clause is redundant when it is nested within the unit.
9403 elsif Nkind (Parent (Cur_Use)) = N_Compilation_Unit
9404 and then Nkind (Parent (Parent (Clause))) /= N_Compilation_Unit
9405 and then Get_Source_Unit (Cur_Use) = Get_Source_Unit (Clause)
9407 Redundant := Clause;
9408 Prev_Use := Cur_Use;
9412 if Present (Redundant) and then Parent (Redundant) /= Prev_Use then
9414 -- Make sure we are looking at most-descendant use_package_clause
9415 -- by traversing the chain with Find_Most_Prev and then verifying
9416 -- there is no scope manipulation via Most_Descendant_Use_Clause.
9418 if Nkind (Prev_Use) = N_Use_Package_Clause
9420 (Nkind (Parent (Prev_Use)) /= N_Compilation_Unit
9421 or else Most_Descendant_Use_Clause
9422 (Prev_Use, Find_Most_Prev (Prev_Use)) /= Prev_Use)
9424 Prev_Use := Find_Most_Prev (Prev_Use);
9427 Error_Msg_Sloc := Sloc (Prev_Use);
9428 Error_Msg_NE -- CODEFIX
9429 ("& is already use-visible through previous use_clause #??",
9430 Redundant, Pack_Name);
9432 end Note_Redundant_Use;
9436 Current_Instance : Entity_Id := Empty;
9440 Private_With_OK : Boolean := False;
9443 -- Start of processing for Use_One_Package
9446 -- Use_One_Package may have been called recursively to handle an
9447 -- implicit use for a auxiliary system package, so set P accordingly
9448 -- and skip redundancy checks.
9450 if No (Pack_Name) and then Present_System_Aux (N) then
9453 -- Check for redundant use_package_clauses
9456 -- Ignore cases where we are dealing with a non user defined package
9457 -- like Standard_Standard or something other than a valid package.
9459 if not Is_Entity_Name (Pack_Name)
9460 or else No (Entity (Pack_Name))
9461 or else Ekind (Entity (Pack_Name)) /= E_Package
9466 -- When a renaming exists we must check it for redundancy. The
9467 -- original package would have already been seen at this point.
9469 if Present (Renamed_Object (Entity (Pack_Name))) then
9470 P := Renamed_Object (Entity (Pack_Name));
9472 P := Entity (Pack_Name);
9475 -- Check for redundant clauses then set the current use clause for
9476 -- P if were are not "forcing" an installation from a scope
9477 -- reinstallation that is done throughout analysis for various
9481 Note_Redundant_Use (Pack_Name);
9484 Set_Current_Use_Clause (P, N);
9489 -- Warn about detected redundant clauses
9492 and then In_Open_Scopes (P)
9493 and then not Is_Hidden_Open_Scope (P)
9495 if Warn_On_Redundant_Constructs and then P = Current_Scope then
9496 Error_Msg_NE -- CODEFIX
9497 ("& is already use-visible within itself?r?",
9504 -- Set P back to the non-renamed package so that visiblilty of the
9505 -- entities within the package can be properly set below.
9507 P := Entity (Pack_Name);
9511 Set_Current_Use_Clause (P, N);
9513 -- Ada 2005 (AI-50217): Check restriction
9515 if From_Limited_With (P) then
9516 Error_Msg_N ("limited withed package cannot appear in use clause", N);
9519 -- Find enclosing instance, if any
9522 Current_Instance := Current_Scope;
9523 while not Is_Generic_Instance (Current_Instance) loop
9524 Current_Instance := Scope (Current_Instance);
9527 if No (Hidden_By_Use_Clause (N)) then
9528 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
9532 -- If unit is a package renaming, indicate that the renamed package is
9533 -- also in use (the flags on both entities must remain consistent, and a
9534 -- subsequent use of either of them should be recognized as redundant).
9536 if Present (Renamed_Object (P)) then
9537 Set_In_Use (Renamed_Object (P));
9538 Set_Current_Use_Clause (Renamed_Object (P), N);
9539 Real_P := Renamed_Object (P);
9544 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
9545 -- found in the private part of a package specification
9547 if In_Private_Part (Current_Scope)
9548 and then Has_Private_With (P)
9549 and then Is_Child_Unit (Current_Scope)
9550 and then Is_Child_Unit (P)
9551 and then Is_Ancestor_Package (Scope (Current_Scope), P)
9553 Private_With_OK := True;
9556 -- Loop through entities in one package making them potentially
9559 Id := First_Entity (P);
9561 and then (Id /= First_Private_Entity (P)
9562 or else Private_With_OK) -- Ada 2005 (AI-262)
9564 Prev := Current_Entity (Id);
9565 while Present (Prev) loop
9566 if Is_Immediately_Visible (Prev)
9567 and then (not Is_Overloadable (Prev)
9568 or else not Is_Overloadable (Id)
9569 or else (Type_Conformant (Id, Prev)))
9571 if No (Current_Instance) then
9573 -- Potentially use-visible entity remains hidden
9575 goto Next_Usable_Entity;
9577 -- A use clause within an instance hides outer global entities,
9578 -- which are not used to resolve local entities in the
9579 -- instance. Note that the predefined entities in Standard
9580 -- could not have been hidden in the generic by a use clause,
9581 -- and therefore remain visible. Other compilation units whose
9582 -- entities appear in Standard must be hidden in an instance.
9584 -- To determine whether an entity is external to the instance
9585 -- we compare the scope depth of its scope with that of the
9586 -- current instance. However, a generic actual of a subprogram
9587 -- instance is declared in the wrapper package but will not be
9588 -- hidden by a use-visible entity. similarly, an entity that is
9589 -- declared in an enclosing instance will not be hidden by an
9590 -- an entity declared in a generic actual, which can only have
9591 -- been use-visible in the generic and will not have hidden the
9592 -- entity in the generic parent.
9594 -- If Id is called Standard, the predefined package with the
9595 -- same name is in the homonym chain. It has to be ignored
9596 -- because it has no defined scope (being the only entity in
9597 -- the system with this mandated behavior).
9599 elsif not Is_Hidden (Id)
9600 and then Present (Scope (Prev))
9601 and then not Is_Wrapper_Package (Scope (Prev))
9602 and then Scope_Depth (Scope (Prev)) <
9603 Scope_Depth (Current_Instance)
9604 and then (Scope (Prev) /= Standard_Standard
9605 or else Sloc (Prev) > Standard_Location)
9607 if In_Open_Scopes (Scope (Prev))
9608 and then Is_Generic_Instance (Scope (Prev))
9609 and then Present (Associated_Formal_Package (P))
9614 Set_Is_Potentially_Use_Visible (Id);
9615 Set_Is_Immediately_Visible (Prev, False);
9616 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
9620 -- A user-defined operator is not use-visible if the predefined
9621 -- operator for the type is immediately visible, which is the case
9622 -- if the type of the operand is in an open scope. This does not
9623 -- apply to user-defined operators that have operands of different
9624 -- types, because the predefined mixed mode operations (multiply
9625 -- and divide) apply to universal types and do not hide anything.
9627 elsif Ekind (Prev) = E_Operator
9628 and then Operator_Matches_Spec (Prev, Id)
9629 and then In_Open_Scopes
9630 (Scope (Base_Type (Etype (First_Formal (Id)))))
9631 and then (No (Next_Formal (First_Formal (Id)))
9632 or else Etype (First_Formal (Id)) =
9633 Etype (Next_Formal (First_Formal (Id)))
9634 or else Chars (Prev) = Name_Op_Expon)
9636 goto Next_Usable_Entity;
9638 -- In an instance, two homonyms may become use_visible through the
9639 -- actuals of distinct formal packages. In the generic, only the
9640 -- current one would have been visible, so make the other one
9643 elsif Present (Current_Instance)
9644 and then Is_Potentially_Use_Visible (Prev)
9645 and then not Is_Overloadable (Prev)
9646 and then Scope (Id) /= Scope (Prev)
9647 and then Used_As_Generic_Actual (Scope (Prev))
9648 and then Used_As_Generic_Actual (Scope (Id))
9649 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
9650 Current_Use_Clause (Scope (Id)))
9652 Set_Is_Potentially_Use_Visible (Prev, False);
9653 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
9656 Prev := Homonym (Prev);
9659 -- On exit, we know entity is not hidden, unless it is private
9661 if not Is_Hidden (Id)
9662 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
9664 Set_Is_Potentially_Use_Visible (Id);
9666 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
9667 Set_Is_Potentially_Use_Visible (Full_View (Id));
9671 <<Next_Usable_Entity>>
9675 -- Child units are also made use-visible by a use clause, but they may
9676 -- appear after all visible declarations in the parent entity list.
9678 while Present (Id) loop
9679 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
9680 Set_Is_Potentially_Use_Visible (Id);
9686 if Chars (Real_P) = Name_System
9687 and then Scope (Real_P) = Standard_Standard
9688 and then Present_System_Aux (N)
9690 Use_One_Package (N);
9692 end Use_One_Package;
9698 procedure Use_One_Type
9700 Installed : Boolean := False;
9701 Force : Boolean := False)
9703 function Spec_Reloaded_For_Body return Boolean;
9704 -- Determine whether the compilation unit is a package body and the use
9705 -- type clause is in the spec of the same package. Even though the spec
9706 -- was analyzed first, its context is reloaded when analysing the body.
9708 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
9709 -- AI05-150: if the use_type_clause carries the "all" qualifier,
9710 -- class-wide operations of ancestor types are use-visible if the
9711 -- ancestor type is visible.
9713 ----------------------------
9714 -- Spec_Reloaded_For_Body --
9715 ----------------------------
9717 function Spec_Reloaded_For_Body return Boolean is
9719 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
9721 Spec : constant Node_Id :=
9722 Parent (List_Containing (Parent (Id)));
9725 -- Check whether type is declared in a package specification,
9726 -- and current unit is the corresponding package body. The
9727 -- use clauses themselves may be within a nested package.
9730 Nkind (Spec) = N_Package_Specification
9731 and then In_Same_Source_Unit
9732 (Corresponding_Body (Parent (Spec)),
9733 Cunit_Entity (Current_Sem_Unit));
9738 end Spec_Reloaded_For_Body;
9740 -------------------------------
9741 -- Use_Class_Wide_Operations --
9742 -------------------------------
9744 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
9745 function Is_Class_Wide_Operation_Of
9747 T : Entity_Id) return Boolean;
9748 -- Determine whether a subprogram has a class-wide parameter or
9749 -- result that is T'Class.
9751 ---------------------------------
9752 -- Is_Class_Wide_Operation_Of --
9753 ---------------------------------
9755 function Is_Class_Wide_Operation_Of
9757 T : Entity_Id) return Boolean
9762 Formal := First_Formal (Op);
9763 while Present (Formal) loop
9764 if Etype (Formal) = Class_Wide_Type (T) then
9768 Next_Formal (Formal);
9771 if Etype (Op) = Class_Wide_Type (T) then
9776 end Is_Class_Wide_Operation_Of;
9783 -- Start of processing for Use_Class_Wide_Operations
9786 Scop := Scope (Typ);
9787 if not Is_Hidden (Scop) then
9788 Ent := First_Entity (Scop);
9789 while Present (Ent) loop
9790 if Is_Overloadable (Ent)
9791 and then Is_Class_Wide_Operation_Of (Ent, Typ)
9792 and then not Is_Potentially_Use_Visible (Ent)
9794 Set_Is_Potentially_Use_Visible (Ent);
9795 Append_Elmt (Ent, Used_Operations (Parent (Id)));
9802 if Is_Derived_Type (Typ) then
9803 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
9805 end Use_Class_Wide_Operations;
9810 Is_Known_Used : Boolean;
9814 -- Start of processing for Use_One_Type
9817 if Entity (Id) = Any_Type then
9821 -- It is the type determined by the subtype mark (8.4(8)) whose
9822 -- operations become potentially use-visible.
9824 T := Base_Type (Entity (Id));
9826 -- Either the type itself is used, the package where it is declared is
9827 -- in use or the entity is declared in the current package, thus
9832 and then ((Present (Current_Use_Clause (T))
9833 and then All_Present (Current_Use_Clause (T)))
9834 or else not All_Present (Parent (Id))))
9835 or else In_Use (Scope (T))
9836 or else Scope (T) = Current_Scope;
9838 Set_Redundant_Use (Id,
9839 Is_Known_Used or else Is_Potentially_Use_Visible (T));
9841 if Ekind (T) = E_Incomplete_Type then
9842 Error_Msg_N ("premature usage of incomplete type", Id);
9844 elsif In_Open_Scopes (Scope (T)) then
9847 -- A limited view cannot appear in a use_type_clause. However, an access
9848 -- type whose designated type is limited has the flag but is not itself
9849 -- a limited view unless we only have a limited view of its enclosing
9852 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
9854 ("incomplete type from limited view cannot appear in use clause",
9857 -- If the use clause is redundant, Used_Operations will usually be
9858 -- empty, but we need to set it to empty here in one case: If we are
9859 -- instantiating a generic library unit, then we install the ancestors
9860 -- of that unit in the scope stack, which involves reprocessing use
9861 -- clauses in those ancestors. Such a use clause will typically have a
9862 -- nonempty Used_Operations unless it was redundant in the generic unit,
9863 -- even if it is redundant at the place of the instantiation.
9865 elsif Redundant_Use (Id) then
9867 -- We must avoid incorrectly setting the Current_Use_Clause when we
9868 -- are working with a redundant clause that has already been linked
9869 -- in the Prev_Use_Clause chain, otherwise the chain will break.
9871 if Present (Current_Use_Clause (T))
9872 and then Present (Prev_Use_Clause (Current_Use_Clause (T)))
9873 and then Parent (Id) = Prev_Use_Clause (Current_Use_Clause (T))
9877 Set_Current_Use_Clause (T, Parent (Id));
9880 Set_Used_Operations (Parent (Id), New_Elmt_List);
9882 -- If the subtype mark designates a subtype in a different package,
9883 -- we have to check that the parent type is visible, otherwise the
9884 -- use_type_clause is a no-op. Not clear how to do that???
9887 Set_Current_Use_Clause (T, Parent (Id));
9890 -- If T is tagged, primitive operators on class-wide operands are
9893 if Is_Tagged_Type (T) then
9894 Set_In_Use (Class_Wide_Type (T));
9897 -- Iterate over primitive operations of the type. If an operation is
9898 -- already use_visible, it is the result of a previous use_clause,
9899 -- and already appears on the corresponding entity chain. If the
9900 -- clause is being reinstalled, operations are already use-visible.
9906 Op_List := Collect_Primitive_Operations (T);
9907 Elmt := First_Elmt (Op_List);
9908 while Present (Elmt) loop
9909 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
9910 or else Chars (Node (Elmt)) in Any_Operator_Name)
9911 and then not Is_Hidden (Node (Elmt))
9912 and then not Is_Potentially_Use_Visible (Node (Elmt))
9914 Set_Is_Potentially_Use_Visible (Node (Elmt));
9915 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9917 elsif Ada_Version >= Ada_2012
9918 and then All_Present (Parent (Id))
9919 and then not Is_Hidden (Node (Elmt))
9920 and then not Is_Potentially_Use_Visible (Node (Elmt))
9922 Set_Is_Potentially_Use_Visible (Node (Elmt));
9923 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9930 if Ada_Version >= Ada_2012
9931 and then All_Present (Parent (Id))
9932 and then Is_Tagged_Type (T)
9934 Use_Class_Wide_Operations (T);
9938 -- If warning on redundant constructs, check for unnecessary WITH
9941 and then Warn_On_Redundant_Constructs
9942 and then Is_Known_Used
9944 -- with P; with P; use P;
9945 -- package P is package X is package body X is
9946 -- type T ... use P.T;
9948 -- The compilation unit is the body of X. GNAT first compiles the
9949 -- spec of X, then proceeds to the body. At that point P is marked
9950 -- as use visible. The analysis then reinstalls the spec along with
9951 -- its context. The use clause P.T is now recognized as redundant,
9952 -- but in the wrong context. Do not emit a warning in such cases.
9953 -- Do not emit a warning either if we are in an instance, there is
9954 -- no redundancy between an outer use_clause and one that appears
9955 -- within the generic.
9957 and then not Spec_Reloaded_For_Body
9958 and then not In_Instance
9959 and then not In_Inlined_Body
9961 -- The type already has a use clause
9965 -- Case where we know the current use clause for the type
9967 if Present (Current_Use_Clause (T)) then
9968 Use_Clause_Known : declare
9969 Clause1 : constant Node_Id :=
9970 Find_Most_Prev (Current_Use_Clause (T));
9971 Clause2 : constant Node_Id := Parent (Id);
9978 -- Start of processing for Use_Clause_Known
9981 -- If both current use_type_clause and the use_type_clause
9982 -- for the type are at the compilation unit level, one of
9983 -- the units must be an ancestor of the other, and the
9984 -- warning belongs on the descendant.
9986 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9988 Nkind (Parent (Clause2)) = N_Compilation_Unit
9990 -- If the unit is a subprogram body that acts as spec,
9991 -- the context clause is shared with the constructed
9992 -- subprogram spec. Clearly there is no redundancy.
9994 if Clause1 = Clause2 then
9998 Unit1 := Unit (Parent (Clause1));
9999 Unit2 := Unit (Parent (Clause2));
10001 -- If both clauses are on same unit, or one is the body
10002 -- of the other, or one of them is in a subunit, report
10003 -- redundancy on the later one.
10005 if Unit1 = Unit2 or else Nkind (Unit1) = N_Subunit then
10006 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
10007 Error_Msg_NE -- CODEFIX
10008 ("& is already use-visible through previous "
10009 & "use_type_clause #??", Clause1, T);
10012 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
10013 and then Nkind (Unit1) /= Nkind (Unit2)
10014 and then Nkind (Unit1) /= N_Subunit
10016 Error_Msg_Sloc := Sloc (Clause1);
10017 Error_Msg_NE -- CODEFIX
10018 ("& is already use-visible through previous "
10019 & "use_type_clause #??", Current_Use_Clause (T), T);
10023 -- There is a redundant use_type_clause in a child unit.
10024 -- Determine which of the units is more deeply nested.
10025 -- If a unit is a package instance, retrieve the entity
10026 -- and its scope from the instance spec.
10028 Ent1 := Entity_Of_Unit (Unit1);
10029 Ent2 := Entity_Of_Unit (Unit2);
10031 if Scope (Ent2) = Standard_Standard then
10032 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
10035 elsif Scope (Ent1) = Standard_Standard then
10036 Error_Msg_Sloc := Sloc (Id);
10039 -- If both units are child units, we determine which one
10040 -- is the descendant by the scope distance to the
10041 -- ultimate parent unit.
10049 S1 := Scope (Ent1);
10050 S2 := Scope (Ent2);
10052 and then Present (S2)
10053 and then S1 /= Standard_Standard
10054 and then S2 /= Standard_Standard
10060 if S1 = Standard_Standard then
10061 Error_Msg_Sloc := Sloc (Id);
10064 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
10070 if Parent (Id) /= Err_No then
10071 if Most_Descendant_Use_Clause
10072 (Err_No, Parent (Id)) = Parent (Id)
10074 Error_Msg_Sloc := Sloc (Err_No);
10075 Err_No := Parent (Id);
10078 Error_Msg_NE -- CODEFIX
10079 ("& is already use-visible through previous "
10080 & "use_type_clause #??", Err_No, Id);
10083 -- Case where current use_type_clause and use_type_clause
10084 -- for the type are not both at the compilation unit level.
10085 -- In this case we don't have location information.
10088 Error_Msg_NE -- CODEFIX
10089 ("& is already use-visible through previous "
10090 & "use_type_clause??", Id, T);
10092 end Use_Clause_Known;
10094 -- Here if Current_Use_Clause is not set for T, another case where
10095 -- we do not have the location information available.
10098 Error_Msg_NE -- CODEFIX
10099 ("& is already use-visible through previous "
10100 & "use_type_clause??", Id, T);
10103 -- The package where T is declared is already used
10105 elsif In_Use (Scope (T)) then
10107 Sloc (Find_Most_Prev (Current_Use_Clause (Scope (T))));
10108 Error_Msg_NE -- CODEFIX
10109 ("& is already use-visible through package use clause #??",
10112 -- The current scope is the package where T is declared
10115 Error_Msg_Node_2 := Scope (T);
10116 Error_Msg_NE -- CODEFIX
10117 ("& is already use-visible inside package &??", Id, T);
10126 procedure Write_Info is
10127 Id : Entity_Id := First_Entity (Current_Scope);
10130 -- No point in dumping standard entities
10132 if Current_Scope = Standard_Standard then
10136 Write_Str ("========================================================");
10138 Write_Str (" Defined Entities in ");
10139 Write_Name (Chars (Current_Scope));
10141 Write_Str ("========================================================");
10145 Write_Str ("-- none --");
10149 while Present (Id) loop
10150 Write_Entity_Info (Id, " ");
10155 if Scope (Current_Scope) = Standard_Standard then
10157 -- Print information on the current unit itself
10159 Write_Entity_Info (Current_Scope, " ");
10172 for J in reverse 1 .. Scope_Stack.Last loop
10173 S := Scope_Stack.Table (J).Entity;
10174 Write_Int (Int (S));
10175 Write_Str (" === ");
10176 Write_Name (Chars (S));
10185 procedure we (S : Entity_Id) is
10188 E := First_Entity (S);
10189 while Present (E) loop
10190 Write_Int (Int (E));
10191 Write_Str (" === ");
10192 Write_Name (Chars (E));