1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Disp
; use Exp_Disp
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Fname
; use Fname
;
35 with Freeze
; use Freeze
;
36 with Ghost
; use Ghost
;
37 with Impunit
; use Impunit
;
39 with Lib
.Load
; use Lib
.Load
;
40 with Lib
.Xref
; use Lib
.Xref
;
41 with Namet
; use Namet
;
42 with Namet
.Sp
; use Namet
.Sp
;
43 with Nlists
; use Nlists
;
44 with Nmake
; use Nmake
;
46 with Output
; use Output
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
51 with Sem_Aux
; use Sem_Aux
;
52 with Sem_Cat
; use Sem_Cat
;
53 with Sem_Ch3
; use Sem_Ch3
;
54 with Sem_Ch4
; use Sem_Ch4
;
55 with Sem_Ch6
; use Sem_Ch6
;
56 with Sem_Ch12
; use Sem_Ch12
;
57 with Sem_Ch13
; use Sem_Ch13
;
58 with Sem_Dim
; use Sem_Dim
;
59 with Sem_Disp
; use Sem_Disp
;
60 with Sem_Dist
; use Sem_Dist
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Res
; use Sem_Res
;
63 with Sem_Util
; use Sem_Util
;
64 with Sem_Type
; use Sem_Type
;
65 with Stand
; use Stand
;
66 with Sinfo
; use Sinfo
;
67 with Sinfo
.CN
; use Sinfo
.CN
;
68 with Snames
; use Snames
;
69 with Style
; use Style
;
71 with Tbuild
; use Tbuild
;
72 with Uintp
; use Uintp
;
74 package body Sem_Ch8
is
76 ------------------------------------
77 -- Visibility and Name Resolution --
78 ------------------------------------
80 -- This package handles name resolution and the collection of possible
81 -- interpretations for overloaded names, prior to overload resolution.
83 -- Name resolution is the process that establishes a mapping between source
84 -- identifiers and the entities they denote at each point in the program.
85 -- Each entity is represented by a defining occurrence. Each identifier
86 -- that denotes an entity points to the corresponding defining occurrence.
87 -- This is the entity of the applied occurrence. Each occurrence holds
88 -- an index into the names table, where source identifiers are stored.
90 -- Each entry in the names table for an identifier or designator uses the
91 -- Info pointer to hold a link to the currently visible entity that has
92 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
93 -- in package Sem_Util). The visibility is initialized at the beginning of
94 -- semantic processing to make entities in package Standard immediately
95 -- visible. The visibility table is used in a more subtle way when
96 -- compiling subunits (see below).
98 -- Entities that have the same name (i.e. homonyms) are chained. In the
99 -- case of overloaded entities, this chain holds all the possible meanings
100 -- of a given identifier. The process of overload resolution uses type
101 -- information to select from this chain the unique meaning of a given
104 -- Entities are also chained in their scope, through the Next_Entity link.
105 -- As a consequence, the name space is organized as a sparse matrix, where
106 -- each row corresponds to a scope, and each column to a source identifier.
107 -- Open scopes, that is to say scopes currently being compiled, have their
108 -- corresponding rows of entities in order, innermost scope first.
110 -- The scopes of packages that are mentioned in context clauses appear in
111 -- no particular order, interspersed among open scopes. This is because
112 -- in the course of analyzing the context of a compilation, a package
113 -- declaration is first an open scope, and subsequently an element of the
114 -- context. If subunits or child units are present, a parent unit may
115 -- appear under various guises at various times in the compilation.
117 -- When the compilation of the innermost scope is complete, the entities
118 -- defined therein are no longer visible. If the scope is not a package
119 -- declaration, these entities are never visible subsequently, and can be
120 -- removed from visibility chains. If the scope is a package declaration,
121 -- its visible declarations may still be accessible. Therefore the entities
122 -- defined in such a scope are left on the visibility chains, and only
123 -- their visibility (immediately visibility or potential use-visibility)
126 -- The ordering of homonyms on their chain does not necessarily follow
127 -- the order of their corresponding scopes on the scope stack. For
128 -- example, if package P and the enclosing scope both contain entities
129 -- named E, then when compiling the package body the chain for E will
130 -- hold the global entity first, and the local one (corresponding to
131 -- the current inner scope) next. As a result, name resolution routines
132 -- do not assume any relative ordering of the homonym chains, either
133 -- for scope nesting or to order of appearance of context clauses.
135 -- When compiling a child unit, entities in the parent scope are always
136 -- immediately visible. When compiling the body of a child unit, private
137 -- entities in the parent must also be made immediately visible. There
138 -- are separate routines to make the visible and private declarations
139 -- visible at various times (see package Sem_Ch7).
141 -- +--------+ +-----+
142 -- | In use |-------->| EU1 |-------------------------->
143 -- +--------+ +-----+
145 -- +--------+ +-----+ +-----+
146 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
147 -- +--------+ +-----+ +-----+
149 -- +---------+ | +-----+
150 -- | with'ed |------------------------------>| EW2 |--->
151 -- +---------+ | +-----+
153 -- +--------+ +-----+ +-----+
154 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
155 -- +--------+ +-----+ +-----+
157 -- +--------+ +-----+ +-----+
158 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
159 -- +--------+ +-----+ +-----+
163 -- | | with'ed |----------------------------------------->
167 -- (innermost first) | |
168 -- +----------------------------+
169 -- Names table => | Id1 | | | | Id2 |
170 -- +----------------------------+
172 -- Name resolution must deal with several syntactic forms: simple names,
173 -- qualified names, indexed names, and various forms of calls.
175 -- Each identifier points to an entry in the names table. The resolution
176 -- of a simple name consists in traversing the homonym chain, starting
177 -- from the names table. If an entry is immediately visible, it is the one
178 -- designated by the identifier. If only potentially use-visible entities
179 -- are on the chain, we must verify that they do not hide each other. If
180 -- the entity we find is overloadable, we collect all other overloadable
181 -- entities on the chain as long as they are not hidden.
183 -- To resolve expanded names, we must find the entity at the intersection
184 -- of the entity chain for the scope (the prefix) and the homonym chain
185 -- for the selector. In general, homonym chains will be much shorter than
186 -- entity chains, so it is preferable to start from the names table as
187 -- well. If the entity found is overloadable, we must collect all other
188 -- interpretations that are defined in the scope denoted by the prefix.
190 -- For records, protected types, and tasks, their local entities are
191 -- removed from visibility chains on exit from the corresponding scope.
192 -- From the outside, these entities are always accessed by selected
193 -- notation, and the entity chain for the record type, protected type,
194 -- etc. is traversed sequentially in order to find the designated entity.
196 -- The discriminants of a type and the operations of a protected type or
197 -- task are unchained on exit from the first view of the type, (such as
198 -- a private or incomplete type declaration, or a protected type speci-
199 -- fication) and re-chained when compiling the second view.
201 -- In the case of operators, we do not make operators on derived types
202 -- explicit. As a result, the notation P."+" may denote either a user-
203 -- defined function with name "+", or else an implicit declaration of the
204 -- operator "+" in package P. The resolution of expanded names always
205 -- tries to resolve an operator name as such an implicitly defined entity,
206 -- in addition to looking for explicit declarations.
208 -- All forms of names that denote entities (simple names, expanded names,
209 -- character literals in some cases) have a Entity attribute, which
210 -- identifies the entity denoted by the name.
212 ---------------------
213 -- The Scope Stack --
214 ---------------------
216 -- The Scope stack keeps track of the scopes currently been compiled.
217 -- Every entity that contains declarations (including records) is placed
218 -- on the scope stack while it is being processed, and removed at the end.
219 -- Whenever a non-package scope is exited, the entities defined therein
220 -- are removed from the visibility table, so that entities in outer scopes
221 -- become visible (see previous description). On entry to Sem, the scope
222 -- stack only contains the package Standard. As usual, subunits complicate
223 -- this picture ever so slightly.
225 -- The Rtsfind mechanism can force a call to Semantics while another
226 -- compilation is in progress. The unit retrieved by Rtsfind must be
227 -- compiled in its own context, and has no access to the visibility of
228 -- the unit currently being compiled. The procedures Save_Scope_Stack and
229 -- Restore_Scope_Stack make entities in current open scopes invisible
230 -- before compiling the retrieved unit, and restore the compilation
231 -- environment afterwards.
233 ------------------------
234 -- Compiling subunits --
235 ------------------------
237 -- Subunits must be compiled in the environment of the corresponding stub,
238 -- that is to say with the same visibility into the parent (and its
239 -- context) that is available at the point of the stub declaration, but
240 -- with the additional visibility provided by the context clause of the
241 -- subunit itself. As a result, compilation of a subunit forces compilation
242 -- of the parent (see description in lib-). At the point of the stub
243 -- declaration, Analyze is called recursively to compile the proper body of
244 -- the subunit, but without reinitializing the names table, nor the scope
245 -- stack (i.e. standard is not pushed on the stack). In this fashion the
246 -- context of the subunit is added to the context of the parent, and the
247 -- subunit is compiled in the correct environment. Note that in the course
248 -- of processing the context of a subunit, Standard will appear twice on
249 -- the scope stack: once for the parent of the subunit, and once for the
250 -- unit in the context clause being compiled. However, the two sets of
251 -- entities are not linked by homonym chains, so that the compilation of
252 -- any context unit happens in a fresh visibility environment.
254 -------------------------------
255 -- Processing of USE Clauses --
256 -------------------------------
258 -- Every defining occurrence has a flag indicating if it is potentially use
259 -- visible. Resolution of simple names examines this flag. The processing
260 -- of use clauses consists in setting this flag on all visible entities
261 -- defined in the corresponding package. On exit from the scope of the use
262 -- clause, the corresponding flag must be reset. However, a package may
263 -- appear in several nested use clauses (pathological but legal, alas)
264 -- which forces us to use a slightly more involved scheme:
266 -- a) The defining occurrence for a package holds a flag -In_Use- to
267 -- indicate that it is currently in the scope of a use clause. If a
268 -- redundant use clause is encountered, then the corresponding occurrence
269 -- of the package name is flagged -Redundant_Use-.
271 -- b) On exit from a scope, the use clauses in its declarative part are
272 -- scanned. The visibility flag is reset in all entities declared in
273 -- package named in a use clause, as long as the package is not flagged
274 -- as being in a redundant use clause (in which case the outer use
275 -- clause is still in effect, and the direct visibility of its entities
276 -- must be retained).
278 -- Note that entities are not removed from their homonym chains on exit
279 -- from the package specification. A subsequent use clause does not need
280 -- to rechain the visible entities, but only to establish their direct
283 -----------------------------------
284 -- Handling private declarations --
285 -----------------------------------
287 -- The principle that each entity has a single defining occurrence clashes
288 -- with the presence of two separate definitions for private types: the
289 -- first is the private type declaration, and second is the full type
290 -- declaration. It is important that all references to the type point to
291 -- the same defining occurrence, namely the first one. To enforce the two
292 -- separate views of the entity, the corresponding information is swapped
293 -- between the two declarations. Outside of the package, the defining
294 -- occurrence only contains the private declaration information, while in
295 -- the private part and the body of the package the defining occurrence
296 -- contains the full declaration. To simplify the swap, the defining
297 -- occurrence that currently holds the private declaration points to the
298 -- full declaration. During semantic processing the defining occurrence
299 -- also points to a list of private dependents, that is to say access types
300 -- or composite types whose designated types or component types are
301 -- subtypes or derived types of the private type in question. After the
302 -- full declaration has been seen, the private dependents are updated to
303 -- indicate that they have full definitions.
305 ------------------------------------
306 -- Handling of Undefined Messages --
307 ------------------------------------
309 -- In normal mode, only the first use of an undefined identifier generates
310 -- a message. The table Urefs is used to record error messages that have
311 -- been issued so that second and subsequent ones do not generate further
312 -- messages. However, the second reference causes text to be added to the
313 -- original undefined message noting "(more references follow)". The
314 -- full error list option (-gnatf) forces messages to be generated for
315 -- every reference and disconnects the use of this table.
317 type Uref_Entry
is record
319 -- Node for identifier for which original message was posted. The
320 -- Chars field of this identifier is used to detect later references
321 -- to the same identifier.
324 -- Records error message Id of original undefined message. Reset to
325 -- No_Error_Msg after the second occurrence, where it is used to add
326 -- text to the original message as described above.
329 -- Set if the message is not visible rather than undefined
332 -- Records location of error message. Used to make sure that we do
333 -- not consider a, b : undefined as two separate instances, which
334 -- would otherwise happen, since the parser converts this sequence
335 -- to a : undefined; b : undefined.
339 package Urefs
is new Table
.Table
(
340 Table_Component_Type
=> Uref_Entry
,
341 Table_Index_Type
=> Nat
,
342 Table_Low_Bound
=> 1,
344 Table_Increment
=> 100,
345 Table_Name
=> "Urefs");
347 Candidate_Renaming
: Entity_Id
;
348 -- Holds a candidate interpretation that appears in a subprogram renaming
349 -- declaration and does not match the given specification, but matches at
350 -- least on the first formal. Allows better error message when given
351 -- specification omits defaulted parameters, a common error.
353 -----------------------
354 -- Local Subprograms --
355 -----------------------
357 procedure Analyze_Generic_Renaming
360 -- Common processing for all three kinds of generic renaming declarations.
361 -- Enter new name and indicate that it renames the generic unit.
363 procedure Analyze_Renamed_Character
367 -- Renamed entity is given by a character literal, which must belong
368 -- to the return type of the new entity. Is_Body indicates whether the
369 -- declaration is a renaming_as_body. If the original declaration has
370 -- already been frozen (because of an intervening body, e.g.) the body of
371 -- the function must be built now. The same applies to the following
372 -- various renaming procedures.
374 procedure Analyze_Renamed_Dereference
378 -- Renamed entity is given by an explicit dereference. Prefix must be a
379 -- conformant access_to_subprogram type.
381 procedure Analyze_Renamed_Entry
385 -- If the renamed entity in a subprogram renaming is an entry or protected
386 -- subprogram, build a body for the new entity whose only statement is a
387 -- call to the renamed entity.
389 procedure Analyze_Renamed_Family_Member
393 -- Used when the renamed entity is an indexed component. The prefix must
394 -- denote an entry family.
396 procedure Analyze_Renamed_Primitive_Operation
400 -- If the renamed entity in a subprogram renaming is a primitive operation
401 -- or a class-wide operation in prefix form, save the target object,
402 -- which must be added to the list of actuals in any subsequent call.
403 -- The renaming operation is intrinsic because the compiler must in
404 -- fact generate a wrapper for it (6.3.1 (10 1/2)).
406 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
407 -- Common code to Use_One_Package and Set_Use, to determine whether use
408 -- clause must be processed. Pack_Name is an entity name that references
409 -- the package in question.
411 procedure Attribute_Renaming
(N
: Node_Id
);
412 -- Analyze renaming of attribute as subprogram. The renaming declaration N
413 -- is rewritten as a subprogram body that returns the attribute reference
414 -- applied to the formals of the function.
416 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
);
417 -- Set Entity, with style check if need be. For a discriminant reference,
418 -- replace by the corresponding discriminal, i.e. the parameter of the
419 -- initialization procedure that corresponds to the discriminant.
421 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
422 -- A renaming_as_body may occur after the entity of the original decla-
423 -- ration has been frozen. In that case, the body of the new entity must
424 -- be built now, because the usual mechanism of building the renamed
425 -- body at the point of freezing will not work. Subp is the subprogram
426 -- for which N provides the Renaming_As_Body.
428 procedure Check_In_Previous_With_Clause
431 -- N is a use_package clause and Nam the package name, or N is a use_type
432 -- clause and Nam is the prefix of the type name. In either case, verify
433 -- that the package is visible at that point in the context: either it
434 -- appears in a previous with_clause, or because it is a fully qualified
435 -- name and the root ancestor appears in a previous with_clause.
437 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
438 -- Verify that the entity in a renaming declaration that is a library unit
439 -- is itself a library unit and not a nested unit or subunit. Also check
440 -- that if the renaming is a child unit of a generic parent, then the
441 -- renamed unit must also be a child unit of that parent. Finally, verify
442 -- that a renamed generic unit is not an implicit child declared within
443 -- an instance of the parent.
445 procedure Chain_Use_Clause
(N
: Node_Id
);
446 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
447 -- the proper scope table entry. This is usually the current scope, but it
448 -- will be an inner scope when installing the use clauses of the private
449 -- declarations of a parent unit prior to compiling the private part of a
450 -- child unit. This chain is traversed when installing/removing use clauses
451 -- when compiling a subunit or instantiating a generic body on the fly,
452 -- when it is necessary to save and restore full environments.
454 function Enclosing_Instance
return Entity_Id
;
455 -- In an instance nested within another one, several semantic checks are
456 -- unnecessary because the legality of the nested instance has been checked
457 -- in the enclosing generic unit. This applies in particular to legality
458 -- checks on actuals for formal subprograms of the inner instance, which
459 -- are checked as subprogram renamings, and may be complicated by confusion
460 -- in private/full views. This function returns the instance enclosing the
461 -- current one if there is such, else it returns Empty.
463 -- If the renaming determines the entity for the default of a formal
464 -- subprogram nested within another instance, choose the innermost
465 -- candidate. This is because if the formal has a box, and we are within
466 -- an enclosing instance where some candidate interpretations are local
467 -- to this enclosing instance, we know that the default was properly
468 -- resolved when analyzing the generic, so we prefer the local
469 -- candidates to those that are external. This is not always the case
470 -- but is a reasonable heuristic on the use of nested generics. The
471 -- proper solution requires a full renaming model.
473 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
474 -- Find a type derived from Character or Wide_Character in the prefix of N.
475 -- Used to resolved qualified names whose selector is a character literal.
477 function Has_Private_With
(E
: Entity_Id
) return Boolean;
478 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
479 -- private with on E.
481 procedure Find_Expanded_Name
(N
: Node_Id
);
482 -- The input is a selected component known to be an expanded name. Verify
483 -- legality of selector given the scope denoted by prefix, and change node
484 -- N into a expanded name with a properly set Entity field.
486 function Find_Renamed_Entity
490 Is_Actual
: Boolean := False) return Entity_Id
;
491 -- Find the renamed entity that corresponds to the given parameter profile
492 -- in a subprogram renaming declaration. The renamed entity may be an
493 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
494 -- indicates that the renaming is the one generated for an actual subpro-
495 -- gram in an instance, for which special visibility checks apply.
497 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
498 -- N is an expanded name whose selector is an operator name (e.g. P."+").
499 -- declarative part contains an implicit declaration of an operator if it
500 -- has a declaration of a type to which one of the predefined operators
501 -- apply. The existence of this routine is an implementation artifact. A
502 -- more straightforward but more space-consuming choice would be to make
503 -- all inherited operators explicit in the symbol table.
505 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
506 -- A subprogram defined by a renaming declaration inherits the parameter
507 -- profile of the renamed entity. The subtypes given in the subprogram
508 -- specification are discarded and replaced with those of the renamed
509 -- subprogram, which are then used to recheck the default values.
511 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
512 -- Prefix is appropriate for record if it is of a record type, or an access
515 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
516 -- True if it is of a task type, a protected type, or else an access to one
519 procedure Note_Redundant_Use
(Clause
: Node_Id
);
520 -- Mark the name in a use clause as redundant if the corresponding entity
521 -- is already use-visible. Emit a warning if the use clause comes from
522 -- source and the proper warnings are enabled.
524 procedure Premature_Usage
(N
: Node_Id
);
525 -- Diagnose usage of an entity before it is visible
527 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
528 -- Make visible entities declared in package P potentially use-visible
529 -- in the current context. Also used in the analysis of subunits, when
530 -- re-installing use clauses of parent units. N is the use_clause that
531 -- names P (and possibly other packages).
533 procedure Use_One_Type
(Id
: Node_Id
; Installed
: Boolean := False);
534 -- Id is the subtype mark from a use type clause. This procedure makes
535 -- the primitive operators of the type potentially use-visible. The
536 -- boolean flag Installed indicates that the clause is being reinstalled
537 -- after previous analysis, and primitive operations are already chained
538 -- on the Used_Operations list of the clause.
540 procedure Write_Info
;
541 -- Write debugging information on entities declared in current scope
543 --------------------------------
544 -- Analyze_Exception_Renaming --
545 --------------------------------
547 -- The language only allows a single identifier, but the tree holds an
548 -- identifier list. The parser has already issued an error message if
549 -- there is more than one element in the list.
551 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
552 Id
: constant Entity_Id
:= Defining_Entity
(N
);
553 Nam
: constant Node_Id
:= Name
(N
);
556 Check_SPARK_05_Restriction
("exception renaming is not allowed", N
);
561 Set_Ekind
(Id
, E_Exception
);
562 Set_Etype
(Id
, Standard_Exception_Type
);
563 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
565 if Is_Entity_Name
(Nam
)
566 and then Present
(Entity
(Nam
))
567 and then Ekind
(Entity
(Nam
)) = E_Exception
569 if Present
(Renamed_Object
(Entity
(Nam
))) then
570 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
572 Set_Renamed_Object
(Id
, Entity
(Nam
));
575 -- The exception renaming declaration may become Ghost if it renames
578 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
580 Error_Msg_N
("invalid exception name in renaming", Nam
);
583 -- Implementation-defined aspect specifications can appear in a renaming
584 -- declaration, but not language-defined ones. The call to procedure
585 -- Analyze_Aspect_Specifications will take care of this error check.
587 if Has_Aspects
(N
) then
588 Analyze_Aspect_Specifications
(N
, Id
);
590 end Analyze_Exception_Renaming
;
592 ---------------------------
593 -- Analyze_Expanded_Name --
594 ---------------------------
596 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
598 -- If the entity pointer is already set, this is an internal node, or a
599 -- node that is analyzed more than once, after a tree modification. In
600 -- such a case there is no resolution to perform, just set the type. In
601 -- either case, start by analyzing the prefix.
603 Analyze
(Prefix
(N
));
605 if Present
(Entity
(N
)) then
606 if Is_Type
(Entity
(N
)) then
607 Set_Etype
(N
, Entity
(N
));
609 Set_Etype
(N
, Etype
(Entity
(N
)));
614 Find_Expanded_Name
(N
);
617 Analyze_Dimension
(N
);
618 end Analyze_Expanded_Name
;
620 ---------------------------------------
621 -- Analyze_Generic_Function_Renaming --
622 ---------------------------------------
624 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
626 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
627 end Analyze_Generic_Function_Renaming
;
629 --------------------------------------
630 -- Analyze_Generic_Package_Renaming --
631 --------------------------------------
633 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
635 -- Test for the Text_IO special unit case here, since we may be renaming
636 -- one of the subpackages of Text_IO, then join common routine.
638 Check_Text_IO_Special_Unit
(Name
(N
));
640 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
641 end Analyze_Generic_Package_Renaming
;
643 ----------------------------------------
644 -- Analyze_Generic_Procedure_Renaming --
645 ----------------------------------------
647 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
649 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
650 end Analyze_Generic_Procedure_Renaming
;
652 ------------------------------
653 -- Analyze_Generic_Renaming --
654 ------------------------------
656 procedure Analyze_Generic_Renaming
660 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
663 Inst
: Boolean := False;
664 -- Prevent junk warning
667 if Name
(N
) = Error
then
671 Check_SPARK_05_Restriction
("generic renaming is not allowed", N
);
673 Generate_Definition
(New_P
);
675 if Current_Scope
/= Standard_Standard
then
676 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
679 if Nkind
(Name
(N
)) = N_Selected_Component
then
680 Check_Generic_Child_Unit
(Name
(N
), Inst
);
685 if not Is_Entity_Name
(Name
(N
)) then
686 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
689 Old_P
:= Entity
(Name
(N
));
693 Set_Ekind
(New_P
, K
);
695 if Etype
(Old_P
) = Any_Type
then
698 elsif Ekind
(Old_P
) /= K
then
699 Error_Msg_N
("invalid generic unit name", Name
(N
));
702 if Present
(Renamed_Object
(Old_P
)) then
703 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
705 Set_Renamed_Object
(New_P
, Old_P
);
708 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
709 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
711 Set_Etype
(New_P
, Etype
(Old_P
));
712 Set_Has_Completion
(New_P
);
714 -- The generic renaming declaration may become Ghost if it renames a
717 Mark_Renaming_As_Ghost
(N
, Old_P
);
719 if In_Open_Scopes
(Old_P
) then
720 Error_Msg_N
("within its scope, generic denotes its instance", N
);
723 -- For subprograms, propagate the Intrinsic flag, to allow, e.g.
724 -- renamings and subsequent instantiations of Unchecked_Conversion.
726 if Ekind_In
(Old_P
, E_Generic_Function
, E_Generic_Procedure
) then
727 Set_Is_Intrinsic_Subprogram
728 (New_P
, Is_Intrinsic_Subprogram
(Old_P
));
731 Check_Library_Unit_Renaming
(N
, Old_P
);
734 -- Implementation-defined aspect specifications can appear in a renaming
735 -- declaration, but not language-defined ones. The call to procedure
736 -- Analyze_Aspect_Specifications will take care of this error check.
738 if Has_Aspects
(N
) then
739 Analyze_Aspect_Specifications
(N
, New_P
);
741 end Analyze_Generic_Renaming
;
743 -----------------------------
744 -- Analyze_Object_Renaming --
745 -----------------------------
747 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
748 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
749 Loc
: constant Source_Ptr
:= Sloc
(N
);
750 Nam
: constant Node_Id
:= Name
(N
);
755 procedure Check_Constrained_Object
;
756 -- If the nominal type is unconstrained but the renamed object is
757 -- constrained, as can happen with renaming an explicit dereference or
758 -- a function return, build a constrained subtype from the object. If
759 -- the renaming is for a formal in an accept statement, the analysis
760 -- has already established its actual subtype. This is only relevant
761 -- if the renamed object is an explicit dereference.
763 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
764 -- Determine whether entity E is inside a generic cope
766 ------------------------------
767 -- Check_Constrained_Object --
768 ------------------------------
770 procedure Check_Constrained_Object
is
771 Typ
: constant Entity_Id
:= Etype
(Nam
);
775 if Nkind_In
(Nam
, N_Function_Call
, N_Explicit_Dereference
)
776 and then Is_Composite_Type
(Etype
(Nam
))
777 and then not Is_Constrained
(Etype
(Nam
))
778 and then not Has_Unknown_Discriminants
(Etype
(Nam
))
779 and then Expander_Active
781 -- If Actual_Subtype is already set, nothing to do
783 if Ekind_In
(Id
, E_Variable
, E_Constant
)
784 and then Present
(Actual_Subtype
(Id
))
788 -- A renaming of an unchecked union has no actual subtype
790 elsif Is_Unchecked_Union
(Typ
) then
793 -- If a record is limited its size is invariant. This is the case
794 -- in particular with record types with an access discirminant
795 -- that are used in iterators. This is an optimization, but it
796 -- also prevents typing anomalies when the prefix is further
797 -- expanded. Limited types with discriminants are included.
799 elsif Is_Limited_Record
(Typ
)
801 (Ekind
(Typ
) = E_Limited_Private_Type
802 and then Has_Discriminants
(Typ
)
803 and then Is_Access_Type
(Etype
(First_Discriminant
(Typ
))))
808 Subt
:= Make_Temporary
(Loc
, 'T');
809 Remove_Side_Effects
(Nam
);
811 Make_Subtype_Declaration
(Loc
,
812 Defining_Identifier
=> Subt
,
813 Subtype_Indication
=>
814 Make_Subtype_From_Expr
(Nam
, Typ
)));
815 Rewrite
(Subtype_Mark
(N
), New_Occurrence_Of
(Subt
, Loc
));
816 Set_Etype
(Nam
, Subt
);
818 -- Freeze subtype at once, to prevent order of elaboration
819 -- issues in the backend. The renamed object exists, so its
820 -- type is already frozen in any case.
822 Freeze_Before
(N
, Subt
);
825 end Check_Constrained_Object
;
827 ----------------------
828 -- In_Generic_Scope --
829 ----------------------
831 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
836 while Present
(S
) and then S
/= Standard_Standard
loop
837 if Is_Generic_Unit
(S
) then
845 end In_Generic_Scope
;
847 -- Start of processing for Analyze_Object_Renaming
854 Check_SPARK_05_Restriction
("object renaming is not allowed", N
);
856 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
859 -- The renaming of a component that depends on a discriminant requires
860 -- an actual subtype, because in subsequent use of the object Gigi will
861 -- be unable to locate the actual bounds. This explicit step is required
862 -- when the renaming is generated in removing side effects of an
863 -- already-analyzed expression.
865 if Nkind
(Nam
) = N_Selected_Component
and then Analyzed
(Nam
) then
867 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
869 if Present
(Dec
) then
870 Insert_Action
(N
, Dec
);
871 T
:= Defining_Identifier
(Dec
);
875 -- Complete analysis of the subtype mark in any case, for ASIS use
877 if Present
(Subtype_Mark
(N
)) then
878 Find_Type
(Subtype_Mark
(N
));
881 elsif Present
(Subtype_Mark
(N
)) then
882 Find_Type
(Subtype_Mark
(N
));
883 T
:= Entity
(Subtype_Mark
(N
));
886 -- Reject renamings of conversions unless the type is tagged, or
887 -- the conversion is implicit (which can occur for cases of anonymous
888 -- access types in Ada 2012).
890 if Nkind
(Nam
) = N_Type_Conversion
891 and then Comes_From_Source
(Nam
)
892 and then not Is_Tagged_Type
(T
)
895 ("renaming of conversion only allowed for tagged types", Nam
);
900 -- If the renamed object is a function call of a limited type,
901 -- the expansion of the renaming is complicated by the presence
902 -- of various temporaries and subtypes that capture constraints
903 -- of the renamed object. Rewrite node as an object declaration,
904 -- whose expansion is simpler. Given that the object is limited
905 -- there is no copy involved and no performance hit.
907 if Nkind
(Nam
) = N_Function_Call
908 and then Is_Limited_View
(Etype
(Nam
))
909 and then not Is_Constrained
(Etype
(Nam
))
910 and then Comes_From_Source
(N
)
913 Set_Ekind
(Id
, E_Constant
);
915 Make_Object_Declaration
(Loc
,
916 Defining_Identifier
=> Id
,
917 Constant_Present
=> True,
918 Object_Definition
=> New_Occurrence_Of
(Etype
(Nam
), Loc
),
919 Expression
=> Relocate_Node
(Nam
)));
923 -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object
924 -- when renaming declaration has a named access type. The Ada 2012
925 -- coverage rules allow an anonymous access type in the context of
926 -- an expected named general access type, but the renaming rules
927 -- require the types to be the same. (An exception is when the type
928 -- of the renaming is also an anonymous access type, which can only
929 -- happen due to a renaming created by the expander.)
931 if Nkind
(Nam
) = N_Type_Conversion
932 and then not Comes_From_Source
(Nam
)
933 and then Ekind
(Etype
(Expression
(Nam
))) = E_Anonymous_Access_Type
934 and then Ekind
(T
) /= E_Anonymous_Access_Type
936 Wrong_Type
(Expression
(Nam
), T
); -- Should we give better error???
939 -- Check that a class-wide object is not being renamed as an object
940 -- of a specific type. The test for access types is needed to exclude
941 -- cases where the renamed object is a dynamically tagged access
942 -- result, such as occurs in certain expansions.
944 if Is_Tagged_Type
(T
) then
945 Check_Dynamically_Tagged_Expression
951 -- Ada 2005 (AI-230/AI-254): Access renaming
953 else pragma Assert
(Present
(Access_Definition
(N
)));
954 T
:= Access_Definition
956 N
=> Access_Definition
(N
));
960 -- Ada 2005 AI05-105: if the declaration has an anonymous access
961 -- type, the renamed object must also have an anonymous type, and
962 -- this is a name resolution rule. This was implicit in the last part
963 -- of the first sentence in 8.5.1(3/2), and is made explicit by this
966 if not Is_Overloaded
(Nam
) then
967 if Ekind
(Etype
(Nam
)) /= Ekind
(T
) then
969 ("expect anonymous access type in object renaming", N
);
976 Typ
: Entity_Id
:= Empty
;
977 Seen
: Boolean := False;
980 Get_First_Interp
(Nam
, I
, It
);
981 while Present
(It
.Typ
) loop
983 -- Renaming is ambiguous if more than one candidate
984 -- interpretation is type-conformant with the context.
986 if Ekind
(It
.Typ
) = Ekind
(T
) then
987 if Ekind
(T
) = E_Anonymous_Access_Subprogram_Type
990 (Designated_Type
(T
), Designated_Type
(It
.Typ
))
996 ("ambiguous expression in renaming", Nam
);
999 elsif Ekind
(T
) = E_Anonymous_Access_Type
1001 Covers
(Designated_Type
(T
), Designated_Type
(It
.Typ
))
1007 ("ambiguous expression in renaming", Nam
);
1011 if Covers
(T
, It
.Typ
) then
1013 Set_Etype
(Nam
, Typ
);
1014 Set_Is_Overloaded
(Nam
, False);
1018 Get_Next_Interp
(I
, It
);
1025 -- Do not perform the legality checks below when the resolution of
1026 -- the renaming name failed because the associated type is Any_Type.
1028 if Etype
(Nam
) = Any_Type
then
1031 -- Ada 2005 (AI-231): In the case where the type is defined by an
1032 -- access_definition, the renamed entity shall be of an access-to-
1033 -- constant type if and only if the access_definition defines an
1034 -- access-to-constant type. ARM 8.5.1(4)
1036 elsif Constant_Present
(Access_Definition
(N
))
1037 and then not Is_Access_Constant
(Etype
(Nam
))
1040 ("(Ada 2005): the renamed object is not access-to-constant "
1041 & "(RM 8.5.1(6))", N
);
1043 elsif not Constant_Present
(Access_Definition
(N
))
1044 and then Is_Access_Constant
(Etype
(Nam
))
1047 ("(Ada 2005): the renamed object is not access-to-variable "
1048 & "(RM 8.5.1(6))", N
);
1051 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1052 Check_Subtype_Conformant
1053 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1055 elsif not Subtypes_Statically_Match
1056 (Designated_Type
(T
),
1057 Available_View
(Designated_Type
(Etype
(Nam
))))
1060 ("subtype of renamed object does not statically match", N
);
1064 -- Special processing for renaming function return object. Some errors
1065 -- and warnings are produced only for calls that come from source.
1067 if Nkind
(Nam
) = N_Function_Call
then
1070 -- Usage is illegal in Ada 83, but renamings are also introduced
1071 -- during expansion, and error does not apply to those.
1074 if Comes_From_Source
(N
) then
1076 ("(Ada 83) cannot rename function return object", Nam
);
1079 -- In Ada 95, warn for odd case of renaming parameterless function
1080 -- call if this is not a limited type (where this is useful).
1083 if Warn_On_Object_Renames_Function
1084 and then No
(Parameter_Associations
(Nam
))
1085 and then not Is_Limited_Type
(Etype
(Nam
))
1086 and then Comes_From_Source
(Nam
)
1089 ("renaming function result object is suspicious?R?", Nam
);
1091 ("\function & will be called only once?R?", Nam
,
1092 Entity
(Name
(Nam
)));
1093 Error_Msg_N
-- CODEFIX
1094 ("\suggest using an initialized constant "
1095 & "object instead?R?", Nam
);
1101 Check_Constrained_Object
;
1103 -- An object renaming requires an exact match of the type. Class-wide
1104 -- matching is not allowed.
1106 if Is_Class_Wide_Type
(T
)
1107 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1109 Wrong_Type
(Nam
, T
);
1114 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1116 if Nkind
(Nam
) = N_Explicit_Dereference
1117 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1119 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1122 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1123 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1127 -- Ada 2005 (AI-327)
1129 if Ada_Version
>= Ada_2005
1130 and then Nkind
(Nam
) = N_Attribute_Reference
1131 and then Attribute_Name
(Nam
) = Name_Priority
1135 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1138 Nam_Ent
: Entity_Id
;
1141 if Nkind
(Nam
) = N_Attribute_Reference
then
1142 Nam_Ent
:= Entity
(Prefix
(Nam
));
1144 Nam_Ent
:= Entity
(Nam
);
1147 Nam_Decl
:= Parent
(Nam_Ent
);
1149 if Has_Null_Exclusion
(N
)
1150 and then not Has_Null_Exclusion
(Nam_Decl
)
1152 -- Ada 2005 (AI-423): If the object name denotes a generic
1153 -- formal object of a generic unit G, and the object renaming
1154 -- declaration occurs within the body of G or within the body
1155 -- of a generic unit declared within the declarative region
1156 -- of G, then the declaration of the formal object of G must
1157 -- have a null exclusion or a null-excluding subtype.
1159 if Is_Formal_Object
(Nam_Ent
)
1160 and then In_Generic_Scope
(Id
)
1162 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1164 ("renamed formal does not exclude `NULL` "
1165 & "(RM 8.5.1(4.6/2))", N
);
1167 elsif In_Package_Body
(Scope
(Id
)) then
1169 ("formal object does not have a null exclusion"
1170 & "(RM 8.5.1(4.6/2))", N
);
1173 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1174 -- shall exclude null.
1176 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1178 ("renamed object does not exclude `NULL` "
1179 & "(RM 8.5.1(4.6/2))", N
);
1181 -- An instance is illegal if it contains a renaming that
1182 -- excludes null, and the actual does not. The renaming
1183 -- declaration has already indicated that the declaration
1184 -- of the renamed actual in the instance will raise
1185 -- constraint_error.
1187 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1188 and then In_Instance
1190 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1191 and then Nkind
(Expression
(Nam_Decl
)) =
1192 N_Raise_Constraint_Error
1195 ("renamed actual does not exclude `NULL` "
1196 & "(RM 8.5.1(4.6/2))", N
);
1198 -- Finally, if there is a null exclusion, the subtype mark
1199 -- must not be null-excluding.
1201 elsif No
(Access_Definition
(N
))
1202 and then Can_Never_Be_Null
(T
)
1205 ("`NOT NULL` not allowed (& already excludes null)",
1210 elsif Can_Never_Be_Null
(T
)
1211 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1214 ("renamed object does not exclude `NULL` "
1215 & "(RM 8.5.1(4.6/2))", N
);
1217 elsif Has_Null_Exclusion
(N
)
1218 and then No
(Access_Definition
(N
))
1219 and then Can_Never_Be_Null
(T
)
1222 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1227 -- Set the Ekind of the entity, unless it has been set already, as is
1228 -- the case for the iteration object over a container with no variable
1229 -- indexing. In that case it's been marked as a constant, and we do not
1230 -- want to change it to a variable.
1232 if Ekind
(Id
) /= E_Constant
then
1233 Set_Ekind
(Id
, E_Variable
);
1236 -- Initialize the object size and alignment. Note that we used to call
1237 -- Init_Size_Align here, but that's wrong for objects which have only
1238 -- an Esize, not an RM_Size field.
1240 Init_Object_Size_Align
(Id
);
1242 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1245 -- Verify that the renamed entity is an object or a function call. It
1246 -- may have been rewritten in several ways.
1248 elsif Is_Object_Reference
(Nam
) then
1249 if Comes_From_Source
(N
) then
1250 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1252 ("illegal renaming of discriminant-dependent component", Nam
);
1255 -- If the renaming comes from source and the renamed object is a
1256 -- dereference, then mark the prefix as needing debug information,
1257 -- since it might have been rewritten hence internally generated
1258 -- and Debug_Renaming_Declaration will link the renaming to it.
1260 if Nkind
(Nam
) = N_Explicit_Dereference
1261 and then Is_Entity_Name
(Prefix
(Nam
))
1263 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1267 -- A static function call may have been folded into a literal
1269 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1271 -- When expansion is disabled, attribute reference is not rewritten
1272 -- as function call. Otherwise it may be rewritten as a conversion,
1273 -- so check original node.
1275 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1276 and then Is_Function_Attribute_Name
1277 (Attribute_Name
(Original_Node
(Nam
))))
1279 -- Weird but legal, equivalent to renaming a function call. Illegal
1280 -- if the literal is the result of constant-folding an attribute
1281 -- reference that is not a function.
1283 or else (Is_Entity_Name
(Nam
)
1284 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1286 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1288 or else (Nkind
(Nam
) = N_Type_Conversion
1289 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1293 elsif Nkind
(Nam
) = N_Type_Conversion
then
1295 ("renaming of conversion only allowed for tagged types", Nam
);
1297 -- Ada 2005 (AI-327)
1299 elsif Ada_Version
>= Ada_2005
1300 and then Nkind
(Nam
) = N_Attribute_Reference
1301 and then Attribute_Name
(Nam
) = Name_Priority
1305 -- Allow internally generated x'Ref resulting in N_Reference node
1307 elsif Nkind
(Nam
) = N_Reference
then
1311 Error_Msg_N
("expect object name in renaming", Nam
);
1316 if not Is_Variable
(Nam
) then
1317 Set_Ekind
(Id
, E_Constant
);
1318 Set_Never_Set_In_Source
(Id
, True);
1319 Set_Is_True_Constant
(Id
, True);
1322 -- The object renaming declaration may become Ghost if it renames a
1325 if Is_Entity_Name
(Nam
) then
1326 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
1329 -- The entity of the renaming declaration needs to reflect whether the
1330 -- renamed object is volatile. Is_Volatile is set if the renamed object
1331 -- is volatile in the RM legality sense.
1333 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1335 -- Also copy settings of Atomic/Independent/Volatile_Full_Access
1337 if Is_Entity_Name
(Nam
) then
1338 Set_Is_Atomic
(Id
, Is_Atomic
(Entity
(Nam
)));
1339 Set_Is_Independent
(Id
, Is_Independent
(Entity
(Nam
)));
1340 Set_Is_Volatile_Full_Access
(Id
,
1341 Is_Volatile_Full_Access
(Entity
(Nam
)));
1344 -- Treat as volatile if we just set the Volatile flag
1348 -- Or if we are renaming an entity which was marked this way
1350 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1352 or else (Is_Entity_Name
(Nam
)
1353 and then Treat_As_Volatile
(Entity
(Nam
)))
1355 Set_Treat_As_Volatile
(Id
, True);
1358 -- Now make the link to the renamed object
1360 Set_Renamed_Object
(Id
, Nam
);
1362 -- Implementation-defined aspect specifications can appear in a renaming
1363 -- declaration, but not language-defined ones. The call to procedure
1364 -- Analyze_Aspect_Specifications will take care of this error check.
1366 if Has_Aspects
(N
) then
1367 Analyze_Aspect_Specifications
(N
, Id
);
1370 -- Deal with dimensions
1372 Analyze_Dimension
(N
);
1373 end Analyze_Object_Renaming
;
1375 ------------------------------
1376 -- Analyze_Package_Renaming --
1377 ------------------------------
1379 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1380 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1385 if Name
(N
) = Error
then
1389 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1391 Check_Text_IO_Special_Unit
(Name
(N
));
1393 if Current_Scope
/= Standard_Standard
then
1394 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1400 if Is_Entity_Name
(Name
(N
)) then
1401 Old_P
:= Entity
(Name
(N
));
1406 if Etype
(Old_P
) = Any_Type
then
1407 Error_Msg_N
("expect package name in renaming", Name
(N
));
1409 elsif Ekind
(Old_P
) /= E_Package
1410 and then not (Ekind
(Old_P
) = E_Generic_Package
1411 and then In_Open_Scopes
(Old_P
))
1413 if Ekind
(Old_P
) = E_Generic_Package
then
1415 ("generic package cannot be renamed as a package", Name
(N
));
1417 Error_Msg_Sloc
:= Sloc
(Old_P
);
1419 ("expect package name in renaming, found& declared#",
1423 -- Set basic attributes to minimize cascaded errors
1425 Set_Ekind
(New_P
, E_Package
);
1426 Set_Etype
(New_P
, Standard_Void_Type
);
1428 -- Here for OK package renaming
1431 -- Entities in the old package are accessible through the renaming
1432 -- entity. The simplest implementation is to have both packages share
1435 Set_Ekind
(New_P
, E_Package
);
1436 Set_Etype
(New_P
, Standard_Void_Type
);
1438 if Present
(Renamed_Object
(Old_P
)) then
1439 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1441 Set_Renamed_Object
(New_P
, Old_P
);
1444 Set_Has_Completion
(New_P
);
1446 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1447 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1448 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1449 Check_Library_Unit_Renaming
(N
, Old_P
);
1450 Generate_Reference
(Old_P
, Name
(N
));
1452 -- The package renaming declaration may become Ghost if it renames a
1455 Mark_Renaming_As_Ghost
(N
, Old_P
);
1457 -- If the renaming is in the visible part of a package, then we set
1458 -- Renamed_In_Spec for the renamed package, to prevent giving
1459 -- warnings about no entities referenced. Such a warning would be
1460 -- overenthusiastic, since clients can see entities in the renamed
1461 -- package via the visible package renaming.
1464 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1466 if Ekind
(Ent
) = E_Package
1467 and then not In_Private_Part
(Ent
)
1468 and then In_Extended_Main_Source_Unit
(N
)
1469 and then Ekind
(Old_P
) = E_Package
1471 Set_Renamed_In_Spec
(Old_P
);
1475 -- If this is the renaming declaration of a package instantiation
1476 -- within itself, it is the declaration that ends the list of actuals
1477 -- for the instantiation. At this point, the subtypes that rename
1478 -- the actuals are flagged as generic, to avoid spurious ambiguities
1479 -- if the actuals for two distinct formals happen to coincide. If
1480 -- the actual is a private type, the subtype has a private completion
1481 -- that is flagged in the same fashion.
1483 -- Resolution is identical to what is was in the original generic.
1484 -- On exit from the generic instance, these are turned into regular
1485 -- subtypes again, so they are compatible with types in their class.
1487 if not Is_Generic_Instance
(Old_P
) then
1490 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1493 if Nkind
(Spec
) = N_Package_Specification
1494 and then Present
(Generic_Parent
(Spec
))
1495 and then Old_P
= Current_Scope
1496 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1502 E
:= First_Entity
(Old_P
);
1503 while Present
(E
) and then E
/= New_P
loop
1505 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1507 Set_Is_Generic_Actual_Type
(E
);
1509 if Is_Private_Type
(E
)
1510 and then Present
(Full_View
(E
))
1512 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1522 -- Implementation-defined aspect specifications can appear in a renaming
1523 -- declaration, but not language-defined ones. The call to procedure
1524 -- Analyze_Aspect_Specifications will take care of this error check.
1526 if Has_Aspects
(N
) then
1527 Analyze_Aspect_Specifications
(N
, New_P
);
1529 end Analyze_Package_Renaming
;
1531 -------------------------------
1532 -- Analyze_Renamed_Character --
1533 -------------------------------
1535 procedure Analyze_Renamed_Character
1540 C
: constant Node_Id
:= Name
(N
);
1543 if Ekind
(New_S
) = E_Function
then
1544 Resolve
(C
, Etype
(New_S
));
1547 Check_Frozen_Renaming
(N
, New_S
);
1551 Error_Msg_N
("character literal can only be renamed as function", N
);
1553 end Analyze_Renamed_Character
;
1555 ---------------------------------
1556 -- Analyze_Renamed_Dereference --
1557 ---------------------------------
1559 procedure Analyze_Renamed_Dereference
1564 Nam
: constant Node_Id
:= Name
(N
);
1565 P
: constant Node_Id
:= Prefix
(Nam
);
1571 if not Is_Overloaded
(P
) then
1572 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1573 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1575 Error_Msg_N
("designated type does not match specification", P
);
1584 Get_First_Interp
(Nam
, Ind
, It
);
1586 while Present
(It
.Nam
) loop
1588 if Ekind
(It
.Nam
) = E_Subprogram_Type
1589 and then Type_Conformant
(It
.Nam
, New_S
)
1591 if Typ
/= Any_Id
then
1592 Error_Msg_N
("ambiguous renaming", P
);
1599 Get_Next_Interp
(Ind
, It
);
1602 if Typ
= Any_Type
then
1603 Error_Msg_N
("designated type does not match specification", P
);
1608 Check_Frozen_Renaming
(N
, New_S
);
1612 end Analyze_Renamed_Dereference
;
1614 ---------------------------
1615 -- Analyze_Renamed_Entry --
1616 ---------------------------
1618 procedure Analyze_Renamed_Entry
1623 Nam
: constant Node_Id
:= Name
(N
);
1624 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1625 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1629 if Entity
(Sel
) = Any_Id
then
1631 -- Selector is undefined on prefix. Error emitted already
1633 Set_Has_Completion
(New_S
);
1637 -- Otherwise find renamed entity and build body of New_S as a call to it
1639 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1641 if Old_S
= Any_Id
then
1642 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1645 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1646 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1647 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1650 -- Only mode conformance required for a renaming_as_declaration
1652 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1655 Inherit_Renamed_Profile
(New_S
, Old_S
);
1657 -- The prefix can be an arbitrary expression that yields a task or
1658 -- protected object, so it must be resolved.
1660 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1663 Set_Convention
(New_S
, Convention
(Old_S
));
1664 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1666 -- AI05-0225: If the renamed entity is a procedure or entry of a
1667 -- protected object, the target object must be a variable.
1669 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1670 and then Ekind
(New_S
) = E_Procedure
1671 and then not Is_Variable
(Prefix
(Nam
))
1675 ("target object of protected operation used as actual for "
1676 & "formal procedure must be a variable", Nam
);
1679 ("target object of protected operation renamed as procedure, "
1680 & "must be a variable", Nam
);
1685 Check_Frozen_Renaming
(N
, New_S
);
1687 end Analyze_Renamed_Entry
;
1689 -----------------------------------
1690 -- Analyze_Renamed_Family_Member --
1691 -----------------------------------
1693 procedure Analyze_Renamed_Family_Member
1698 Nam
: constant Node_Id
:= Name
(N
);
1699 P
: constant Node_Id
:= Prefix
(Nam
);
1703 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1704 or else (Nkind
(P
) = N_Selected_Component
1705 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1707 if Is_Entity_Name
(P
) then
1708 Old_S
:= Entity
(P
);
1710 Old_S
:= Entity
(Selector_Name
(P
));
1713 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1714 Error_Msg_N
("entry family does not match specification", N
);
1717 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1718 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1719 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1723 Error_Msg_N
("no entry family matches specification", N
);
1726 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1729 Check_Frozen_Renaming
(N
, New_S
);
1731 end Analyze_Renamed_Family_Member
;
1733 -----------------------------------------
1734 -- Analyze_Renamed_Primitive_Operation --
1735 -----------------------------------------
1737 procedure Analyze_Renamed_Primitive_Operation
1746 Ctyp
: Conformance_Type
) return Boolean;
1747 -- Verify that the signatures of the renamed entity and the new entity
1748 -- match. The first formal of the renamed entity is skipped because it
1749 -- is the target object in any subsequent call.
1757 Ctyp
: Conformance_Type
) return Boolean
1763 if Ekind
(Subp
) /= Ekind
(New_S
) then
1767 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1768 New_F
:= First_Formal
(New_S
);
1769 while Present
(Old_F
) and then Present
(New_F
) loop
1770 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1774 if Ctyp
>= Mode_Conformant
1775 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1780 Next_Formal
(New_F
);
1781 Next_Formal
(Old_F
);
1787 -- Start of processing for Analyze_Renamed_Primitive_Operation
1790 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1791 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1793 if not Conforms
(Old_S
, Type_Conformant
) then
1798 -- Find the operation that matches the given signature
1806 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1808 while Present
(It
.Nam
) loop
1809 if Conforms
(It
.Nam
, Type_Conformant
) then
1813 Get_Next_Interp
(Ind
, It
);
1818 if Old_S
= Any_Id
then
1819 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1823 if not Conforms
(Old_S
, Subtype_Conformant
) then
1824 Error_Msg_N
("subtype conformance error in renaming", N
);
1827 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1828 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1831 -- Only mode conformance required for a renaming_as_declaration
1833 if not Conforms
(Old_S
, Mode_Conformant
) then
1834 Error_Msg_N
("mode conformance error in renaming", N
);
1837 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1838 -- view of a subprogram is intrinsic, because the compiler has
1839 -- to generate a wrapper for any call to it. If the name in a
1840 -- subprogram renaming is a prefixed view, the entity is thus
1841 -- intrinsic, and 'Access cannot be applied to it.
1843 Set_Convention
(New_S
, Convention_Intrinsic
);
1846 -- Inherit_Renamed_Profile (New_S, Old_S);
1848 -- The prefix can be an arbitrary expression that yields an
1849 -- object, so it must be resolved.
1851 Resolve
(Prefix
(Name
(N
)));
1853 end Analyze_Renamed_Primitive_Operation
;
1855 ---------------------------------
1856 -- Analyze_Subprogram_Renaming --
1857 ---------------------------------
1859 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1860 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1861 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1862 Nam
: constant Node_Id
:= Name
(N
);
1863 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1864 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1865 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1866 Spec
: constant Node_Id
:= Specification
(N
);
1868 Old_S
: Entity_Id
:= Empty
;
1869 Rename_Spec
: Entity_Id
;
1871 procedure Build_Class_Wide_Wrapper
1872 (Ren_Id
: out Entity_Id
;
1873 Wrap_Id
: out Entity_Id
);
1874 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1875 -- type with unknown discriminants and a generic primitive operation of
1876 -- the said type with a box require special processing when the actual
1877 -- is a class-wide type:
1880 -- type Formal_Typ (<>) is private;
1881 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1882 -- package Gen is ...
1884 -- package Inst is new Gen (Actual_Typ'Class);
1886 -- In this case the general renaming mechanism used in the prologue of
1887 -- an instance no longer applies:
1889 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1891 -- The above is replaced the following wrapper/renaming combination:
1893 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1895 -- Prim_Op (Param); -- primitive
1898 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1900 -- This transformation applies only if there is no explicit visible
1901 -- class-wide operation at the point of the instantiation. Ren_Id is
1902 -- the entity of the renaming declaration. Wrap_Id is the entity of
1903 -- the generated class-wide wrapper (or Any_Id).
1905 procedure Check_Null_Exclusion
1908 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1909 -- following AI rules:
1911 -- If Ren is a renaming of a formal subprogram and one of its
1912 -- parameters has a null exclusion, then the corresponding formal
1913 -- in Sub must also have one. Otherwise the subtype of the Sub's
1914 -- formal parameter must exclude null.
1916 -- If Ren is a renaming of a formal function and its return
1917 -- profile has a null exclusion, then Sub's return profile must
1918 -- have one. Otherwise the subtype of Sub's return profile must
1921 procedure Freeze_Actual_Profile
;
1922 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1923 -- types: a callable entity freezes its profile, unless it has an
1924 -- incomplete untagged formal (RM 13.14(10.2/3)).
1926 function Has_Class_Wide_Actual
return Boolean;
1927 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1928 -- defaulted formal subprogram where the actual for the controlling
1929 -- formal type is class-wide.
1931 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1932 -- Find renamed entity when the declaration is a renaming_as_body and
1933 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1934 -- rule that a renaming_as_body is illegal if the declaration occurs
1935 -- before the subprogram it completes is frozen, and renaming indirectly
1936 -- renames the subprogram itself.(Defect Report 8652/0027).
1938 ------------------------------
1939 -- Build_Class_Wide_Wrapper --
1940 ------------------------------
1942 procedure Build_Class_Wide_Wrapper
1943 (Ren_Id
: out Entity_Id
;
1944 Wrap_Id
: out Entity_Id
)
1946 Loc
: constant Source_Ptr
:= Sloc
(N
);
1949 (Subp_Id
: Entity_Id
;
1950 Params
: List_Id
) return Node_Id
;
1951 -- Create a dispatching call to invoke routine Subp_Id with actuals
1952 -- built from the parameter specifications of list Params.
1954 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1955 -- Create a subprogram specification based on the subprogram profile
1958 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1959 -- Find a primitive subprogram of type Typ which matches the profile
1960 -- of the renaming declaration.
1962 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
1963 -- Emit a continuation error message suggesting subprogram Subp_Id as
1964 -- a possible interpretation.
1966 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
1967 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
1970 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
1971 -- Determine whether subprogram Subp_Id is a suitable candidate for
1972 -- the role of a wrapped subprogram.
1979 (Subp_Id
: Entity_Id
;
1980 Params
: List_Id
) return Node_Id
1982 Actuals
: constant List_Id
:= New_List
;
1983 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
1987 -- Build the actual parameters of the call
1989 Formal
:= First
(Params
);
1990 while Present
(Formal
) loop
1992 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
1997 -- return Subp_Id (Actuals);
1999 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
2001 Make_Simple_Return_Statement
(Loc
,
2003 Make_Function_Call
(Loc
,
2005 Parameter_Associations
=> Actuals
));
2008 -- Subp_Id (Actuals);
2012 Make_Procedure_Call_Statement
(Loc
,
2014 Parameter_Associations
=> Actuals
);
2022 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2023 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2024 Spec_Id
: constant Entity_Id
:=
2025 Make_Defining_Identifier
(Loc
,
2026 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2029 if Ekind
(Formal_Spec
) = E_Procedure
then
2031 Make_Procedure_Specification
(Loc
,
2032 Defining_Unit_Name
=> Spec_Id
,
2033 Parameter_Specifications
=> Params
);
2036 Make_Function_Specification
(Loc
,
2037 Defining_Unit_Name
=> Spec_Id
,
2038 Parameter_Specifications
=> Params
,
2039 Result_Definition
=>
2040 New_Copy_Tree
(Result_Definition
(Spec
)));
2044 --------------------
2045 -- Find_Primitive --
2046 --------------------
2048 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2049 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2050 -- Given a specification Spec, replace all class-wide parameter
2051 -- types with reference to type Typ.
2053 -----------------------------
2054 -- Replace_Parameter_Types --
2055 -----------------------------
2057 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2059 Formal_Id
: Entity_Id
;
2060 Formal_Typ
: Node_Id
;
2063 Formal
:= First
(Parameter_Specifications
(Spec
));
2064 while Present
(Formal
) loop
2065 Formal_Id
:= Defining_Identifier
(Formal
);
2066 Formal_Typ
:= Parameter_Type
(Formal
);
2068 -- Create a new entity for each class-wide formal to prevent
2069 -- aliasing with the original renaming. Replace the type of
2070 -- such a parameter with the candidate type.
2072 if Nkind
(Formal_Typ
) = N_Identifier
2073 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2075 Set_Defining_Identifier
(Formal
,
2076 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2078 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2083 end Replace_Parameter_Types
;
2087 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2088 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2089 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2090 Subp_Id
: Entity_Id
;
2092 -- Start of processing for Find_Primitive
2095 -- Each attempt to find a suitable primitive of a particular type
2096 -- operates on its own copy of the original renaming. As a result
2097 -- the original renaming is kept decoration and side-effect free.
2099 -- Inherit the overloaded status of the renamed subprogram name
2101 if Is_Overloaded
(Nam
) then
2102 Set_Is_Overloaded
(Alt_Nam
);
2103 Save_Interps
(Nam
, Alt_Nam
);
2106 -- The copied renaming is hidden from visibility to prevent the
2107 -- pollution of the enclosing context.
2109 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2111 -- The types of all class-wide parameters must be changed to the
2114 Replace_Parameter_Types
(Alt_Spec
);
2116 -- Try to find a suitable primitive which matches the altered
2117 -- profile of the renaming specification.
2122 Nam
=> Name
(Alt_Ren
),
2123 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2124 Is_Actual
=> Is_Actual
);
2126 -- Do not return Any_Id if the resolion of the altered profile
2127 -- failed as this complicates further checks on the caller side,
2128 -- return Empty instead.
2130 if Subp_Id
= Any_Id
then
2137 --------------------------
2138 -- Interpretation_Error --
2139 --------------------------
2141 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2143 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2145 if Is_Internal
(Subp_Id
) then
2147 ("\\possible interpretation: predefined & #",
2151 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2153 end Interpretation_Error
;
2155 ---------------------------
2156 -- Is_Intrinsic_Equality --
2157 ---------------------------
2159 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2162 Ekind
(Subp_Id
) = E_Operator
2163 and then Chars
(Subp_Id
) = Name_Op_Eq
2164 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2165 end Is_Intrinsic_Equality
;
2167 ---------------------------
2168 -- Is_Suitable_Candidate --
2169 ---------------------------
2171 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2173 if No
(Subp_Id
) then
2176 -- An intrinsic subprogram is never a good candidate. This is an
2177 -- indication of a missing primitive, either defined directly or
2178 -- inherited from a parent tagged type.
2180 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2186 end Is_Suitable_Candidate
;
2190 Actual_Typ
: Entity_Id
:= Empty
;
2191 -- The actual class-wide type for Formal_Typ
2193 CW_Prim_OK
: Boolean;
2194 CW_Prim_Op
: Entity_Id
;
2195 -- The class-wide subprogram (if available) which corresponds to the
2196 -- renamed generic formal subprogram.
2198 Formal_Typ
: Entity_Id
:= Empty
;
2199 -- The generic formal type with unknown discriminants
2201 Root_Prim_OK
: Boolean;
2202 Root_Prim_Op
: Entity_Id
;
2203 -- The root type primitive (if available) which corresponds to the
2204 -- renamed generic formal subprogram.
2206 Root_Typ
: Entity_Id
:= Empty
;
2207 -- The root type of Actual_Typ
2209 Body_Decl
: Node_Id
;
2211 Prim_Op
: Entity_Id
;
2212 Spec_Decl
: Node_Id
;
2214 -- Start of processing for Build_Class_Wide_Wrapper
2217 -- Analyze the specification of the renaming in case the generation
2218 -- of the class-wide wrapper fails.
2220 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2223 -- Do not attempt to build a wrapper if the renaming is in error
2225 if Error_Posted
(Nam
) then
2229 -- Analyze the renamed name, but do not resolve it. The resolution is
2230 -- completed once a suitable subprogram is found.
2234 -- When the renamed name denotes the intrinsic operator equals, the
2235 -- name must be treated as overloaded. This allows for a potential
2236 -- match against the root type's predefined equality function.
2238 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2239 Set_Is_Overloaded
(Nam
);
2240 Collect_Interps
(Nam
);
2243 -- Step 1: Find the generic formal type with unknown discriminants
2244 -- and its corresponding class-wide actual type from the renamed
2245 -- generic formal subprogram.
2247 Formal
:= First_Formal
(Formal_Spec
);
2248 while Present
(Formal
) loop
2249 if Has_Unknown_Discriminants
(Etype
(Formal
))
2250 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2251 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2253 Formal_Typ
:= Etype
(Formal
);
2254 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2255 Root_Typ
:= Etype
(Actual_Typ
);
2259 Next_Formal
(Formal
);
2262 -- The specification of the generic formal subprogram should always
2263 -- contain a formal type with unknown discriminants whose actual is
2264 -- a class-wide type, otherwise this indicates a failure in routine
2265 -- Has_Class_Wide_Actual.
2267 pragma Assert
(Present
(Formal_Typ
));
2269 -- Step 2: Find the proper class-wide subprogram or primitive which
2270 -- corresponds to the renamed generic formal subprogram.
2272 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2273 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2274 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2275 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2277 -- The class-wide actual type has two subprograms which correspond to
2278 -- the renamed generic formal subprogram:
2280 -- with procedure Prim_Op (Param : Formal_Typ);
2282 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2283 -- procedure Prim_Op (Param : Actual_Typ'Class);
2285 -- Even though the declaration of the two subprograms is legal, a
2286 -- call to either one is ambiguous and therefore illegal.
2288 if CW_Prim_OK
and Root_Prim_OK
then
2290 -- A user-defined primitive has precedence over a predefined one
2292 if Is_Internal
(CW_Prim_Op
)
2293 and then not Is_Internal
(Root_Prim_Op
)
2295 Prim_Op
:= Root_Prim_Op
;
2297 elsif Is_Internal
(Root_Prim_Op
)
2298 and then not Is_Internal
(CW_Prim_Op
)
2300 Prim_Op
:= CW_Prim_Op
;
2302 elsif CW_Prim_Op
= Root_Prim_Op
then
2303 Prim_Op
:= Root_Prim_Op
;
2305 -- Otherwise both candidate subprograms are user-defined and
2310 ("ambiguous actual for generic subprogram &",
2312 Interpretation_Error
(Root_Prim_Op
);
2313 Interpretation_Error
(CW_Prim_Op
);
2317 elsif CW_Prim_OK
and not Root_Prim_OK
then
2318 Prim_Op
:= CW_Prim_Op
;
2320 elsif not CW_Prim_OK
and Root_Prim_OK
then
2321 Prim_Op
:= Root_Prim_Op
;
2323 -- An intrinsic equality may act as a suitable candidate in the case
2324 -- of a null type extension where the parent's equality is hidden. A
2325 -- call to an intrinsic equality is expanded as dispatching.
2327 elsif Present
(Root_Prim_Op
)
2328 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2330 Prim_Op
:= Root_Prim_Op
;
2332 -- Otherwise there are no candidate subprograms. Let the caller
2333 -- diagnose the error.
2339 -- At this point resolution has taken place and the name is no longer
2340 -- overloaded. Mark the primitive as referenced.
2342 Set_Is_Overloaded
(Name
(N
), False);
2343 Set_Referenced
(Prim_Op
);
2345 -- Step 3: Create the declaration and the body of the wrapper, insert
2346 -- all the pieces into the tree.
2349 Make_Subprogram_Declaration
(Loc
,
2350 Specification
=> Build_Spec
(Ren_Id
));
2351 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2353 -- If the operator carries an Eliminated pragma, indicate that the
2354 -- wrapper is also to be eliminated, to prevent spurious error when
2355 -- using gnatelim on programs that include box-initialization of
2356 -- equality operators.
2358 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2359 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2362 Make_Subprogram_Body
(Loc
,
2363 Specification
=> Build_Spec
(Ren_Id
),
2364 Declarations
=> New_List
,
2365 Handled_Statement_Sequence
=>
2366 Make_Handled_Sequence_Of_Statements
(Loc
,
2367 Statements
=> New_List
(
2369 (Subp_Id
=> Prim_Op
,
2371 Parameter_Specifications
2372 (Specification
(Spec_Decl
))))));
2374 -- The generated body does not freeze and must be analyzed when the
2375 -- class-wide wrapper is frozen. The body is only needed if expansion
2378 if Expander_Active
then
2379 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2382 -- Step 4: The subprogram renaming aliases the wrapper
2384 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2385 end Build_Class_Wide_Wrapper
;
2387 --------------------------
2388 -- Check_Null_Exclusion --
2389 --------------------------
2391 procedure Check_Null_Exclusion
2395 Ren_Formal
: Entity_Id
;
2396 Sub_Formal
: Entity_Id
;
2401 Ren_Formal
:= First_Formal
(Ren
);
2402 Sub_Formal
:= First_Formal
(Sub
);
2403 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2404 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2406 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2407 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2410 ("`NOT NULL` required for parameter &",
2411 Parent
(Sub_Formal
), Sub_Formal
);
2414 Next_Formal
(Ren_Formal
);
2415 Next_Formal
(Sub_Formal
);
2418 -- Return profile check
2420 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2421 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2422 and then Has_Null_Exclusion
(Parent
(Ren
))
2423 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2424 or else Can_Never_Be_Null
(Etype
(Sub
)))
2427 ("return must specify `NOT NULL`",
2428 Result_Definition
(Parent
(Sub
)));
2430 end Check_Null_Exclusion
;
2432 ---------------------------
2433 -- Freeze_Actual_Profile --
2434 ---------------------------
2436 procedure Freeze_Actual_Profile
is
2438 Has_Untagged_Inc
: Boolean;
2439 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2442 if Ada_Version
>= Ada_2012
then
2443 F
:= First_Formal
(Formal_Spec
);
2444 Has_Untagged_Inc
:= False;
2445 while Present
(F
) loop
2446 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2447 and then not Is_Tagged_Type
(Etype
(F
))
2449 Has_Untagged_Inc
:= True;
2453 F
:= Next_Formal
(F
);
2456 if Ekind
(Formal_Spec
) = E_Function
2457 and then not Is_Tagged_Type
(Etype
(Formal_Spec
))
2459 Has_Untagged_Inc
:= True;
2462 if not Has_Untagged_Inc
then
2463 F
:= First_Formal
(Old_S
);
2464 while Present
(F
) loop
2465 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2467 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2468 and then No
(Underlying_Type
(Etype
(F
)))
2470 -- Exclude generic types, or types derived from them.
2471 -- They will be frozen in the enclosing instance.
2473 if Is_Generic_Type
(Etype
(F
))
2474 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2478 -- A limited view of a type declared elsewhere needs no
2479 -- freezing actions.
2481 elsif From_Limited_With
(Etype
(F
)) then
2486 ("type& must be frozen before this point",
2487 Instantiation_Node
, Etype
(F
));
2491 F
:= Next_Formal
(F
);
2495 end Freeze_Actual_Profile
;
2497 ---------------------------
2498 -- Has_Class_Wide_Actual --
2499 ---------------------------
2501 function Has_Class_Wide_Actual
return Boolean is
2503 Formal_Typ
: Entity_Id
;
2507 Formal
:= First_Formal
(Formal_Spec
);
2508 while Present
(Formal
) loop
2509 Formal_Typ
:= Etype
(Formal
);
2511 if Has_Unknown_Discriminants
(Formal_Typ
)
2512 and then not Is_Class_Wide_Type
(Formal_Typ
)
2513 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2518 Next_Formal
(Formal
);
2523 end Has_Class_Wide_Actual
;
2525 -------------------------
2526 -- Original_Subprogram --
2527 -------------------------
2529 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2530 Orig_Decl
: Node_Id
;
2531 Orig_Subp
: Entity_Id
;
2534 -- First case: renamed entity is itself a renaming
2536 if Present
(Alias
(Subp
)) then
2537 return Alias
(Subp
);
2539 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2540 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2542 -- Check if renamed entity is a renaming_as_body
2545 Unit_Declaration_Node
2546 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2548 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2549 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2551 if Orig_Subp
= Rename_Spec
then
2553 -- Circularity detected
2558 return (Original_Subprogram
(Orig_Subp
));
2566 end Original_Subprogram
;
2570 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2571 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2572 -- defaulted formal subprogram when the actual for a related formal
2573 -- type is class-wide.
2575 Inst_Node
: Node_Id
:= Empty
;
2578 -- Start of processing for Analyze_Subprogram_Renaming
2581 -- We must test for the attribute renaming case before the Analyze
2582 -- call because otherwise Sem_Attr will complain that the attribute
2583 -- is missing an argument when it is analyzed.
2585 if Nkind
(Nam
) = N_Attribute_Reference
then
2587 -- In the case of an abstract formal subprogram association, rewrite
2588 -- an actual given by a stream attribute as the name of the
2589 -- corresponding stream primitive of the type.
2591 -- In a generic context the stream operations are not generated, and
2592 -- this must be treated as a normal attribute reference, to be
2593 -- expanded in subsequent instantiations.
2596 and then Is_Abstract_Subprogram
(Formal_Spec
)
2597 and then Expander_Active
2600 Stream_Prim
: Entity_Id
;
2601 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2604 -- The class-wide forms of the stream attributes are not
2605 -- primitive dispatching operations (even though they
2606 -- internally dispatch to a stream attribute).
2608 if Is_Class_Wide_Type
(Prefix_Type
) then
2610 ("attribute must be a primitive dispatching operation",
2615 -- Retrieve the primitive subprogram associated with the
2616 -- attribute. This can only be a stream attribute, since those
2617 -- are the only ones that are dispatching (and the actual for
2618 -- an abstract formal subprogram must be dispatching
2621 case Attribute_Name
(Nam
) is
2624 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2627 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2630 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2633 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2636 ("attribute must be a primitive"
2637 & " dispatching operation", Nam
);
2641 -- If no operation was found, and the type is limited,
2642 -- the user should have defined one.
2644 if No
(Stream_Prim
) then
2645 if Is_Limited_Type
(Prefix_Type
) then
2647 ("stream operation not defined for type&",
2651 -- Otherwise, compiler should have generated default
2654 raise Program_Error
;
2658 -- Rewrite the attribute into the name of its corresponding
2659 -- primitive dispatching subprogram. We can then proceed with
2660 -- the usual processing for subprogram renamings.
2663 Prim_Name
: constant Node_Id
:=
2664 Make_Identifier
(Sloc
(Nam
),
2665 Chars
=> Chars
(Stream_Prim
));
2667 Set_Entity
(Prim_Name
, Stream_Prim
);
2668 Rewrite
(Nam
, Prim_Name
);
2673 -- Normal processing for a renaming of an attribute
2676 Attribute_Renaming
(N
);
2681 -- Check whether this declaration corresponds to the instantiation
2682 -- of a formal subprogram.
2684 -- If this is an instantiation, the corresponding actual is frozen and
2685 -- error messages can be made more precise. If this is a default
2686 -- subprogram, the entity is already established in the generic, and is
2687 -- not retrieved by visibility. If it is a default with a box, the
2688 -- candidate interpretations, if any, have been collected when building
2689 -- the renaming declaration. If overloaded, the proper interpretation is
2690 -- determined in Find_Renamed_Entity. If the entity is an operator,
2691 -- Find_Renamed_Entity applies additional visibility checks.
2694 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2696 -- Check whether the renaming is for a defaulted actual subprogram
2697 -- with a class-wide actual.
2699 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2700 -- is an external axiomatization on the package.
2703 and then Box_Present
(Inst_Node
)
2707 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2709 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2711 elsif Is_Entity_Name
(Nam
)
2712 and then Present
(Entity
(Nam
))
2713 and then not Comes_From_Source
(Nam
)
2714 and then not Is_Overloaded
(Nam
)
2716 Old_S
:= Entity
(Nam
);
2717 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2721 if Ekind
(Entity
(Nam
)) = E_Operator
then
2725 if Box_Present
(Inst_Node
) then
2726 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2728 -- If there is an immediately visible homonym of the operator
2729 -- and the declaration has a default, this is worth a warning
2730 -- because the user probably did not intend to get the pre-
2731 -- defined operator, visible in the generic declaration. To
2732 -- find if there is an intended candidate, analyze the renaming
2733 -- again in the current context.
2735 elsif Scope
(Old_S
) = Standard_Standard
2736 and then Present
(Default_Name
(Inst_Node
))
2739 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2743 Set_Entity
(Name
(Decl
), Empty
);
2744 Analyze
(Name
(Decl
));
2746 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2749 and then In_Open_Scopes
(Scope
(Hidden
))
2750 and then Is_Immediately_Visible
(Hidden
)
2751 and then Comes_From_Source
(Hidden
)
2752 and then Hidden
/= Old_S
2754 Error_Msg_Sloc
:= Sloc
(Hidden
);
2755 Error_Msg_N
("default subprogram is resolved " &
2756 "in the generic declaration " &
2757 "(RM 12.6(17))??", N
);
2758 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2766 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2770 -- Renamed entity must be analyzed first, to avoid being hidden by
2771 -- new name (which might be the same in a generic instance).
2775 -- The renaming defines a new overloaded entity, which is analyzed
2776 -- like a subprogram declaration.
2778 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2781 if Current_Scope
/= Standard_Standard
then
2782 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2785 -- Set SPARK mode from current context
2787 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2788 Set_SPARK_Pragma_Inherited
(New_S
);
2790 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2792 -- Case of Renaming_As_Body
2794 if Present
(Rename_Spec
) then
2796 -- Renaming declaration is the completion of the declaration of
2797 -- Rename_Spec. We build an actual body for it at the freezing point.
2799 Set_Corresponding_Spec
(N
, Rename_Spec
);
2801 -- Deal with special case of stream functions of abstract types
2804 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2805 N_Abstract_Subprogram_Declaration
2807 -- Input stream functions are abstract if the object type is
2808 -- abstract. Similarly, all default stream functions for an
2809 -- interface type are abstract. However, these subprograms may
2810 -- receive explicit declarations in representation clauses, making
2811 -- the attribute subprograms usable as defaults in subsequent
2813 -- In this case we rewrite the declaration to make the subprogram
2814 -- non-abstract. We remove the previous declaration, and insert
2815 -- the new one at the point of the renaming, to prevent premature
2816 -- access to unfrozen types. The new declaration reuses the
2817 -- specification of the previous one, and must not be analyzed.
2820 (Is_Primitive
(Entity
(Nam
))
2822 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2824 Old_Decl
: constant Node_Id
:=
2825 Unit_Declaration_Node
(Rename_Spec
);
2826 New_Decl
: constant Node_Id
:=
2827 Make_Subprogram_Declaration
(Sloc
(N
),
2829 Relocate_Node
(Specification
(Old_Decl
)));
2832 Insert_After
(N
, New_Decl
);
2833 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2834 Set_Analyzed
(New_Decl
);
2838 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2840 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2841 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2844 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2845 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2846 Set_Public_Status
(New_S
);
2848 -- The specification does not introduce new formals, but only
2849 -- repeats the formals of the original subprogram declaration.
2850 -- For cross-reference purposes, and for refactoring tools, we
2851 -- treat the formals of the renaming declaration as body formals.
2853 Reference_Body_Formals
(Rename_Spec
, New_S
);
2855 -- Indicate that the entity in the declaration functions like the
2856 -- corresponding body, and is not a new entity. The body will be
2857 -- constructed later at the freeze point, so indicate that the
2858 -- completion has not been seen yet.
2860 Set_Ekind
(New_S
, E_Subprogram_Body
);
2861 New_S
:= Rename_Spec
;
2862 Set_Has_Completion
(Rename_Spec
, False);
2864 -- Ada 2005: check overriding indicator
2866 if Present
(Overridden_Operation
(Rename_Spec
)) then
2867 if Must_Not_Override
(Specification
(N
)) then
2869 ("subprogram& overrides inherited operation",
2872 Style_Check
and then not Must_Override
(Specification
(N
))
2874 Style
.Missing_Overriding
(N
, Rename_Spec
);
2877 elsif Must_Override
(Specification
(N
)) then
2878 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2881 -- Normal subprogram renaming (not renaming as body)
2884 Generate_Definition
(New_S
);
2885 New_Overloaded_Entity
(New_S
);
2887 if Is_Entity_Name
(Nam
)
2888 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2892 Check_Delayed_Subprogram
(New_S
);
2896 -- There is no need for elaboration checks on the new entity, which may
2897 -- be called before the next freezing point where the body will appear.
2898 -- Elaboration checks refer to the real entity, not the one created by
2899 -- the renaming declaration.
2901 Set_Kill_Elaboration_Checks
(New_S
, True);
2903 -- If we had a previous error, indicate a completely is present to stop
2904 -- junk cascaded messages, but don't take any further action.
2906 if Etype
(Nam
) = Any_Type
then
2907 Set_Has_Completion
(New_S
);
2910 -- Case where name has the form of a selected component
2912 elsif Nkind
(Nam
) = N_Selected_Component
then
2914 -- A name which has the form A.B can designate an entry of task A, a
2915 -- protected operation of protected object A, or finally a primitive
2916 -- operation of object A. In the later case, A is an object of some
2917 -- tagged type, or an access type that denotes one such. To further
2918 -- distinguish these cases, note that the scope of a task entry or
2919 -- protected operation is type of the prefix.
2921 -- The prefix could be an overloaded function call that returns both
2922 -- kinds of operations. This overloading pathology is left to the
2923 -- dedicated reader ???
2926 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2934 and then Is_Tagged_Type
(Designated_Type
(T
))))
2935 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2937 Analyze_Renamed_Primitive_Operation
2938 (N
, New_S
, Present
(Rename_Spec
));
2942 -- Renamed entity is an entry or protected operation. For those
2943 -- cases an explicit body is built (at the point of freezing of
2944 -- this entity) that contains a call to the renamed entity.
2946 -- This is not allowed for renaming as body if the renamed
2947 -- spec is already frozen (see RM 8.5.4(5) for details).
2949 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
2951 ("renaming-as-body cannot rename entry as subprogram", N
);
2953 ("\since & is already frozen (RM 8.5.4(5))",
2956 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
2963 -- Case where name is an explicit dereference X.all
2965 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
2967 -- Renamed entity is designated by access_to_subprogram expression.
2968 -- Must build body to encapsulate call, as in the entry case.
2970 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
2973 -- Indexed component
2975 elsif Nkind
(Nam
) = N_Indexed_Component
then
2976 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
2979 -- Character literal
2981 elsif Nkind
(Nam
) = N_Character_Literal
then
2982 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
2985 -- Only remaining case is where we have a non-entity name, or a renaming
2986 -- of some other non-overloadable entity.
2988 elsif not Is_Entity_Name
(Nam
)
2989 or else not Is_Overloadable
(Entity
(Nam
))
2991 -- Do not mention the renaming if it comes from an instance
2993 if not Is_Actual
then
2994 Error_Msg_N
("expect valid subprogram name in renaming", N
);
2996 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
3002 -- Find the renamed entity that matches the given specification. Disable
3003 -- Ada_83 because there is no requirement of full conformance between
3004 -- renamed entity and new entity, even though the same circuit is used.
3006 -- This is a bit of an odd case, which introduces a really irregular use
3007 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3010 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3011 Ada_Version_Pragma
:= Empty
;
3012 Ada_Version_Explicit
:= Ada_Version
;
3015 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3017 -- The visible operation may be an inherited abstract operation that
3018 -- was overridden in the private part, in which case a call will
3019 -- dispatch to the overriding operation. Use the overriding one in
3020 -- the renaming declaration, to prevent spurious errors below.
3022 if Is_Overloadable
(Old_S
)
3023 and then Is_Abstract_Subprogram
(Old_S
)
3024 and then No
(DTC_Entity
(Old_S
))
3025 and then Present
(Alias
(Old_S
))
3026 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3027 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3029 Old_S
:= Alias
(Old_S
);
3032 -- When the renamed subprogram is overloaded and used as an actual
3033 -- of a generic, its entity is set to the first available homonym.
3034 -- We must first disambiguate the name, then set the proper entity.
3036 if Is_Actual
and then Is_Overloaded
(Nam
) then
3037 Set_Entity
(Nam
, Old_S
);
3041 -- Most common case: subprogram renames subprogram. No body is generated
3042 -- in this case, so we must indicate the declaration is complete as is.
3043 -- and inherit various attributes of the renamed subprogram.
3045 if No
(Rename_Spec
) then
3046 Set_Has_Completion
(New_S
);
3047 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3048 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3049 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3051 -- The subprogram renaming declaration may become Ghost if it renames
3054 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
3056 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3057 -- between a subprogram and its correct renaming.
3059 -- Note: the Any_Id check is a guard that prevents compiler crashes
3060 -- when performing a null exclusion check between a renaming and a
3061 -- renamed subprogram that has been found to be illegal.
3063 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3064 Check_Null_Exclusion
3066 Sub
=> Entity
(Nam
));
3069 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3070 -- overriding. The flag Requires_Overriding is set very selectively
3071 -- and misses some other illegal cases. The additional conditions
3072 -- checked below are sufficient but not necessary ???
3074 -- The rule does not apply to the renaming generated for an actual
3075 -- subprogram in an instance.
3080 -- Guard against previous errors, and omit renamings of predefined
3083 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3086 elsif Requires_Overriding
(Old_S
)
3088 (Is_Abstract_Subprogram
(Old_S
)
3089 and then Present
(Find_Dispatching_Type
(Old_S
))
3091 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3094 ("renamed entity cannot be "
3095 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3099 if Old_S
/= Any_Id
then
3100 if Is_Actual
and then From_Default
(N
) then
3102 -- This is an implicit reference to the default actual
3104 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3107 Generate_Reference
(Old_S
, Nam
);
3110 Check_Internal_Protected_Use
(N
, Old_S
);
3112 -- For a renaming-as-body, require subtype conformance, but if the
3113 -- declaration being completed has not been frozen, then inherit the
3114 -- convention of the renamed subprogram prior to checking conformance
3115 -- (unless the renaming has an explicit convention established; the
3116 -- rule stated in the RM doesn't seem to address this ???).
3118 if Present
(Rename_Spec
) then
3119 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3120 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3122 if not Is_Frozen
(Rename_Spec
) then
3123 if not Has_Convention_Pragma
(Rename_Spec
) then
3124 Set_Convention
(New_S
, Convention
(Old_S
));
3127 if Ekind
(Old_S
) /= E_Operator
then
3128 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3131 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3132 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3135 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3138 Check_Frozen_Renaming
(N
, Rename_Spec
);
3140 -- Check explicitly that renamed entity is not intrinsic, because
3141 -- in a generic the renamed body is not built. In this case,
3142 -- the renaming_as_body is a completion.
3144 if Inside_A_Generic
then
3145 if Is_Frozen
(Rename_Spec
)
3146 and then Is_Intrinsic_Subprogram
(Old_S
)
3149 ("subprogram in renaming_as_body cannot be intrinsic",
3153 Set_Has_Completion
(Rename_Spec
);
3156 elsif Ekind
(Old_S
) /= E_Operator
then
3158 -- If this a defaulted subprogram for a class-wide actual there is
3159 -- no check for mode conformance, given that the signatures don't
3160 -- match (the source mentions T but the actual mentions T'Class).
3164 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3165 Check_Mode_Conformant
(New_S
, Old_S
);
3168 if Is_Actual
and then Error_Posted
(New_S
) then
3169 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3173 if No
(Rename_Spec
) then
3175 -- The parameter profile of the new entity is that of the renamed
3176 -- entity: the subtypes given in the specification are irrelevant.
3178 Inherit_Renamed_Profile
(New_S
, Old_S
);
3180 -- A call to the subprogram is transformed into a call to the
3181 -- renamed entity. This is transitive if the renamed entity is
3182 -- itself a renaming.
3184 if Present
(Alias
(Old_S
)) then
3185 Set_Alias
(New_S
, Alias
(Old_S
));
3187 Set_Alias
(New_S
, Old_S
);
3190 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3191 -- renaming as body, since the entity in this case is not an
3192 -- intrinsic (it calls an intrinsic, but we have a real body for
3193 -- this call, and it is in this body that the required intrinsic
3194 -- processing will take place).
3196 -- Also, if this is a renaming of inequality, the renamed operator
3197 -- is intrinsic, but what matters is the corresponding equality
3198 -- operator, which may be user-defined.
3200 Set_Is_Intrinsic_Subprogram
3202 Is_Intrinsic_Subprogram
(Old_S
)
3204 (Chars
(Old_S
) /= Name_Op_Ne
3205 or else Ekind
(Old_S
) = E_Operator
3206 or else Is_Intrinsic_Subprogram
3207 (Corresponding_Equality
(Old_S
))));
3209 if Ekind
(Alias
(New_S
)) = E_Operator
then
3210 Set_Has_Delayed_Freeze
(New_S
, False);
3213 -- If the renaming corresponds to an association for an abstract
3214 -- formal subprogram, then various attributes must be set to
3215 -- indicate that the renaming is an abstract dispatching operation
3216 -- with a controlling type.
3218 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3220 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3221 -- see it as corresponding to a generic association for a
3222 -- formal abstract subprogram
3224 Set_Is_Abstract_Subprogram
(New_S
);
3227 New_S_Ctrl_Type
: constant Entity_Id
:=
3228 Find_Dispatching_Type
(New_S
);
3229 Old_S_Ctrl_Type
: constant Entity_Id
:=
3230 Find_Dispatching_Type
(Old_S
);
3234 -- The actual must match the (instance of the) formal,
3235 -- and must be a controlling type.
3237 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
3238 or else No
(New_S_Ctrl_Type
)
3241 ("actual must be dispatching subprogram for type&",
3242 Nam
, New_S_Ctrl_Type
);
3245 Set_Is_Dispatching_Operation
(New_S
);
3246 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3248 -- If the actual in the formal subprogram is itself a
3249 -- formal abstract subprogram association, there's no
3250 -- dispatch table component or position to inherit.
3252 if Present
(DTC_Entity
(Old_S
)) then
3253 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3254 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3264 -- The following is illegal, because F hides whatever other F may
3266 -- function F (...) renames F;
3269 or else (Nkind
(Nam
) /= N_Expanded_Name
3270 and then Chars
(Old_S
) = Chars
(New_S
))
3272 Error_Msg_N
("subprogram cannot rename itself", N
);
3274 -- This is illegal even if we use a selector:
3275 -- function F (...) renames Pkg.F;
3276 -- because F is still hidden.
3278 elsif Nkind
(Nam
) = N_Expanded_Name
3279 and then Entity
(Prefix
(Nam
)) = Current_Scope
3280 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3282 -- This is an error, but we overlook the error and accept the
3283 -- renaming if the special Overriding_Renamings mode is in effect.
3285 if not Overriding_Renamings
then
3287 ("implicit operation& is not visible (RM 8.3 (15))",
3292 Set_Convention
(New_S
, Convention
(Old_S
));
3294 if Is_Abstract_Subprogram
(Old_S
) then
3295 if Present
(Rename_Spec
) then
3297 ("a renaming-as-body cannot rename an abstract subprogram",
3299 Set_Has_Completion
(Rename_Spec
);
3301 Set_Is_Abstract_Subprogram
(New_S
);
3305 Check_Library_Unit_Renaming
(N
, Old_S
);
3307 -- Pathological case: procedure renames entry in the scope of its
3308 -- task. Entry is given by simple name, but body must be built for
3309 -- procedure. Of course if called it will deadlock.
3311 if Ekind
(Old_S
) = E_Entry
then
3312 Set_Has_Completion
(New_S
, False);
3313 Set_Alias
(New_S
, Empty
);
3317 Freeze_Before
(N
, Old_S
);
3318 Freeze_Actual_Profile
;
3319 Set_Has_Delayed_Freeze
(New_S
, False);
3320 Freeze_Before
(N
, New_S
);
3322 -- An abstract subprogram is only allowed as an actual in the case
3323 -- where the formal subprogram is also abstract.
3325 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3326 and then Is_Abstract_Subprogram
(Old_S
)
3327 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3330 ("abstract subprogram not allowed as generic actual", Nam
);
3335 -- A common error is to assume that implicit operators for types are
3336 -- defined in Standard, or in the scope of a subtype. In those cases
3337 -- where the renamed entity is given with an expanded name, it is
3338 -- worth mentioning that operators for the type are not declared in
3339 -- the scope given by the prefix.
3341 if Nkind
(Nam
) = N_Expanded_Name
3342 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3343 and then Scope
(Entity
(Nam
)) = Standard_Standard
3346 T
: constant Entity_Id
:=
3347 Base_Type
(Etype
(First_Formal
(New_S
)));
3349 Error_Msg_Node_2
:= Prefix
(Nam
);
3351 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3356 ("no visible subprogram matches the specification for&",
3360 if Present
(Candidate_Renaming
) then
3367 F1
:= First_Formal
(Candidate_Renaming
);
3368 F2
:= First_Formal
(New_S
);
3369 T1
:= First_Subtype
(Etype
(F1
));
3370 while Present
(F1
) and then Present
(F2
) loop
3375 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3376 if Present
(Next_Formal
(F1
)) then
3378 ("\missing specification for & and other formals with "
3379 & "defaults", Spec
, F1
);
3381 Error_Msg_NE
("\missing specification for &", Spec
, F1
);
3385 if Nkind
(Nam
) = N_Operator_Symbol
3386 and then From_Default
(N
)
3388 Error_Msg_Node_2
:= T1
;
3390 ("default & on & is not directly visible",
3397 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3398 -- controlling access parameters are known non-null for the renamed
3399 -- subprogram. Test also applies to a subprogram instantiation that
3400 -- is dispatching. Test is skipped if some previous error was detected
3401 -- that set Old_S to Any_Id.
3403 if Ada_Version
>= Ada_2005
3404 and then Old_S
/= Any_Id
3405 and then not Is_Dispatching_Operation
(Old_S
)
3406 and then Is_Dispatching_Operation
(New_S
)
3413 Old_F
:= First_Formal
(Old_S
);
3414 New_F
:= First_Formal
(New_S
);
3415 while Present
(Old_F
) loop
3416 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3417 and then Is_Controlling_Formal
(New_F
)
3418 and then not Can_Never_Be_Null
(Old_F
)
3420 Error_Msg_N
("access parameter is controlling,", New_F
);
3422 ("\corresponding parameter of& "
3423 & "must be explicitly null excluding", New_F
, Old_S
);
3426 Next_Formal
(Old_F
);
3427 Next_Formal
(New_F
);
3432 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3433 -- is to warn if an operator is being renamed as a different operator.
3434 -- If the operator is predefined, examine the kind of the entity, not
3435 -- the abbreviated declaration in Standard.
3437 if Comes_From_Source
(N
)
3438 and then Present
(Old_S
)
3439 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3440 or else Ekind
(Old_S
) = E_Operator
)
3441 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3442 and then Chars
(Old_S
) /= Chars
(New_S
)
3445 ("& is being renamed as a different operator??", N
, Old_S
);
3448 -- Check for renaming of obsolescent subprogram
3450 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3452 -- Another warning or some utility: if the new subprogram as the same
3453 -- name as the old one, the old one is not hidden by an outer homograph,
3454 -- the new one is not a public symbol, and the old one is otherwise
3455 -- directly visible, the renaming is superfluous.
3457 if Chars
(Old_S
) = Chars
(New_S
)
3458 and then Comes_From_Source
(N
)
3459 and then Scope
(Old_S
) /= Standard_Standard
3460 and then Warn_On_Redundant_Constructs
3461 and then (Is_Immediately_Visible
(Old_S
)
3462 or else Is_Potentially_Use_Visible
(Old_S
))
3463 and then Is_Overloadable
(Current_Scope
)
3464 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3467 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3470 -- Implementation-defined aspect specifications can appear in a renaming
3471 -- declaration, but not language-defined ones. The call to procedure
3472 -- Analyze_Aspect_Specifications will take care of this error check.
3474 if Has_Aspects
(N
) then
3475 Analyze_Aspect_Specifications
(N
, New_S
);
3478 Ada_Version
:= Save_AV
;
3479 Ada_Version_Pragma
:= Save_AVP
;
3480 Ada_Version_Explicit
:= Save_AV_Exp
;
3482 -- In GNATprove mode, the renamings of actual subprograms are replaced
3483 -- with wrapper functions that make it easier to propagate axioms to the
3484 -- points of call within an instance. Wrappers are generated if formal
3485 -- subprogram is subject to axiomatization.
3487 -- The types in the wrapper profiles are obtained from (instances of)
3488 -- the types of the formal subprogram.
3491 and then GNATprove_Mode
3492 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3493 and then not Inside_A_Generic
3495 if Ekind
(Old_S
) = E_Function
then
3496 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3499 elsif Ekind
(Old_S
) = E_Operator
then
3500 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3504 end Analyze_Subprogram_Renaming
;
3506 -------------------------
3507 -- Analyze_Use_Package --
3508 -------------------------
3510 -- Resolve the package names in the use clause, and make all the visible
3511 -- entities defined in the package potentially use-visible. If the package
3512 -- is already in use from a previous use clause, its visible entities are
3513 -- already use-visible. In that case, mark the occurrence as a redundant
3514 -- use. If the package is an open scope, i.e. if the use clause occurs
3515 -- within the package itself, ignore it.
3517 procedure Analyze_Use_Package
(N
: Node_Id
) is
3518 Pack_Name
: Node_Id
;
3521 -- Start of processing for Analyze_Use_Package
3524 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3526 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3528 -- Use clause not allowed in a spec of a predefined package declaration
3529 -- except that packages whose file name starts a-n are OK (these are
3530 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3532 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3533 and then Name_Buffer
(1 .. 3) /= "a-n"
3535 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3537 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3540 -- Chain clause to list of use clauses in current scope
3542 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3543 Chain_Use_Clause
(N
);
3546 -- Loop through package names to identify referenced packages
3548 Pack_Name
:= First
(Names
(N
));
3549 while Present
(Pack_Name
) loop
3550 Analyze
(Pack_Name
);
3552 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3553 and then Nkind
(Pack_Name
) = N_Expanded_Name
3559 Pref
:= Prefix
(Pack_Name
);
3560 while Nkind
(Pref
) = N_Expanded_Name
loop
3561 Pref
:= Prefix
(Pref
);
3564 if Entity
(Pref
) = Standard_Standard
then
3566 ("predefined package Standard cannot appear"
3567 & " in a context clause", Pref
);
3575 -- Loop through package names to mark all entities as potentially
3578 Pack_Name
:= First
(Names
(N
));
3579 while Present
(Pack_Name
) loop
3580 if Is_Entity_Name
(Pack_Name
) then
3581 Pack
:= Entity
(Pack_Name
);
3583 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3584 if Ekind
(Pack
) = E_Generic_Package
then
3585 Error_Msg_N
-- CODEFIX
3586 ("a generic package is not allowed in a use clause",
3589 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3591 Error_Msg_N
-- CODEFIX
3592 ("a generic subprogram is not allowed in a use clause",
3595 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3596 Error_Msg_N
-- CODEFIX
3597 ("a subprogram is not allowed in a use clause",
3601 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3605 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3606 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3609 if Applicable_Use
(Pack_Name
) then
3610 Use_One_Package
(Pack
, N
);
3614 -- Report error because name denotes something other than a package
3617 Error_Msg_N
("& is not a package", Pack_Name
);
3622 end Analyze_Use_Package
;
3624 ----------------------
3625 -- Analyze_Use_Type --
3626 ----------------------
3628 procedure Analyze_Use_Type
(N
: Node_Id
) is
3633 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3635 -- Chain clause to list of use clauses in current scope
3637 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3638 Chain_Use_Clause
(N
);
3641 -- If the Used_Operations list is already initialized, the clause has
3642 -- been analyzed previously, and it is begin reinstalled, for example
3643 -- when the clause appears in a package spec and we are compiling the
3644 -- corresponding package body. In that case, make the entities on the
3645 -- existing list use_visible, and mark the corresponding types In_Use.
3647 if Present
(Used_Operations
(N
)) then
3653 Mark
:= First
(Subtype_Marks
(N
));
3654 while Present
(Mark
) loop
3655 Use_One_Type
(Mark
, Installed
=> True);
3659 Elmt
:= First_Elmt
(Used_Operations
(N
));
3660 while Present
(Elmt
) loop
3661 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3669 -- Otherwise, create new list and attach to it the operations that
3670 -- are made use-visible by the clause.
3672 Set_Used_Operations
(N
, New_Elmt_List
);
3673 Id
:= First
(Subtype_Marks
(N
));
3674 while Present
(Id
) loop
3678 if E
/= Any_Type
then
3681 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3682 if Nkind
(Id
) = N_Identifier
then
3683 Error_Msg_N
("type is not directly visible", Id
);
3685 elsif Is_Child_Unit
(Scope
(E
))
3686 and then Scope
(E
) /= System_Aux_Id
3688 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3693 -- If the use_type_clause appears in a compilation unit context,
3694 -- check whether it comes from a unit that may appear in a
3695 -- limited_with_clause, for a better error message.
3697 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3698 and then Nkind
(Id
) /= N_Identifier
3704 function Mentioned
(Nam
: Node_Id
) return Boolean;
3705 -- Check whether the prefix of expanded name for the type
3706 -- appears in the prefix of some limited_with_clause.
3712 function Mentioned
(Nam
: Node_Id
) return Boolean is
3714 return Nkind
(Name
(Item
)) = N_Selected_Component
3715 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3719 Pref
:= Prefix
(Id
);
3720 Item
:= First
(Context_Items
(Parent
(N
)));
3721 while Present
(Item
) and then Item
/= N
loop
3722 if Nkind
(Item
) = N_With_Clause
3723 and then Limited_Present
(Item
)
3724 and then Mentioned
(Pref
)
3727 (Get_Msg_Id
, "premature usage of incomplete type");
3738 end Analyze_Use_Type
;
3740 --------------------
3741 -- Applicable_Use --
3742 --------------------
3744 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3745 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3748 if In_Open_Scopes
(Pack
) then
3749 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3750 Error_Msg_NE
-- CODEFIX
3751 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3756 elsif In_Use
(Pack
) then
3757 Note_Redundant_Use
(Pack_Name
);
3760 elsif Present
(Renamed_Object
(Pack
))
3761 and then In_Use
(Renamed_Object
(Pack
))
3763 Note_Redundant_Use
(Pack_Name
);
3771 ------------------------
3772 -- Attribute_Renaming --
3773 ------------------------
3775 procedure Attribute_Renaming
(N
: Node_Id
) is
3776 Loc
: constant Source_Ptr
:= Sloc
(N
);
3777 Nam
: constant Node_Id
:= Name
(N
);
3778 Spec
: constant Node_Id
:= Specification
(N
);
3779 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3780 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3782 Form_Num
: Nat
:= 0;
3783 Expr_List
: List_Id
:= No_List
;
3785 Attr_Node
: Node_Id
;
3786 Body_Node
: Node_Id
;
3787 Param_Spec
: Node_Id
;
3790 Generate_Definition
(New_S
);
3792 -- This procedure is called in the context of subprogram renaming, and
3793 -- thus the attribute must be one that is a subprogram. All of those
3794 -- have at least one formal parameter, with the exceptions of the GNAT
3795 -- attribute 'Img, which GNAT treats as renameable.
3797 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3798 if Aname
/= Name_Img
then
3800 ("subprogram renaming an attribute must have formals", N
);
3805 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3806 while Present
(Param_Spec
) loop
3807 Form_Num
:= Form_Num
+ 1;
3809 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3810 Find_Type
(Parameter_Type
(Param_Spec
));
3812 -- The profile of the new entity denotes the base type (s) of
3813 -- the types given in the specification. For access parameters
3814 -- there are no subtypes involved.
3816 Rewrite
(Parameter_Type
(Param_Spec
),
3818 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3821 if No
(Expr_List
) then
3822 Expr_List
:= New_List
;
3825 Append_To
(Expr_List
,
3826 Make_Identifier
(Loc
,
3827 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3829 -- The expressions in the attribute reference are not freeze
3830 -- points. Neither is the attribute as a whole, see below.
3832 Set_Must_Not_Freeze
(Last
(Expr_List
));
3837 -- Immediate error if too many formals. Other mismatches in number or
3838 -- types of parameters are detected when we analyze the body of the
3839 -- subprogram that we construct.
3841 if Form_Num
> 2 then
3842 Error_Msg_N
("too many formals for attribute", N
);
3844 -- Error if the attribute reference has expressions that look like
3845 -- formal parameters.
3847 elsif Present
(Expressions
(Nam
)) then
3848 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3851 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3852 Name_Pos
, Name_Round
, Name_Scaling
,
3855 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3856 and then Present
(Corresponding_Formal_Spec
(N
))
3859 ("generic actual cannot be attribute involving universal type",
3863 ("attribute involving a universal type cannot be renamed",
3868 -- Rewrite attribute node to have a list of expressions corresponding to
3869 -- the subprogram formals. A renaming declaration is not a freeze point,
3870 -- and the analysis of the attribute reference should not freeze the
3871 -- type of the prefix. We use the original node in the renaming so that
3872 -- its source location is preserved, and checks on stream attributes are
3873 -- properly applied.
3875 Attr_Node
:= Relocate_Node
(Nam
);
3876 Set_Expressions
(Attr_Node
, Expr_List
);
3878 Set_Must_Not_Freeze
(Attr_Node
);
3879 Set_Must_Not_Freeze
(Prefix
(Nam
));
3881 -- Case of renaming a function
3883 if Nkind
(Spec
) = N_Function_Specification
then
3884 if Is_Procedure_Attribute_Name
(Aname
) then
3885 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3889 Find_Type
(Result_Definition
(Spec
));
3890 Rewrite
(Result_Definition
(Spec
),
3892 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3895 Make_Subprogram_Body
(Loc
,
3896 Specification
=> Spec
,
3897 Declarations
=> New_List
,
3898 Handled_Statement_Sequence
=>
3899 Make_Handled_Sequence_Of_Statements
(Loc
,
3900 Statements
=> New_List
(
3901 Make_Simple_Return_Statement
(Loc
,
3902 Expression
=> Attr_Node
))));
3904 -- Case of renaming a procedure
3907 if not Is_Procedure_Attribute_Name
(Aname
) then
3908 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3913 Make_Subprogram_Body
(Loc
,
3914 Specification
=> Spec
,
3915 Declarations
=> New_List
,
3916 Handled_Statement_Sequence
=>
3917 Make_Handled_Sequence_Of_Statements
(Loc
,
3918 Statements
=> New_List
(Attr_Node
)));
3921 -- In case of tagged types we add the body of the generated function to
3922 -- the freezing actions of the type (because in the general case such
3923 -- type is still not frozen). We exclude from this processing generic
3924 -- formal subprograms found in instantiations.
3926 -- We must exclude restricted run-time libraries because
3927 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3928 -- available in those platforms. Note that we cannot use the function
3929 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3930 -- the ZFP run-time library is not defined as a profile, and we do not
3931 -- want to deal with AST_Handler in ZFP mode.
3933 if not Configurable_Run_Time_Mode
3934 and then not Present
(Corresponding_Formal_Spec
(N
))
3935 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
3938 P
: constant Node_Id
:= Prefix
(Nam
);
3941 -- The prefix of 'Img is an object that is evaluated for each call
3942 -- of the function that renames it.
3944 if Aname
= Name_Img
then
3945 Preanalyze_And_Resolve
(P
);
3947 -- For all other attribute renamings, the prefix is a subtype
3953 -- If the target type is not yet frozen, add the body to the
3954 -- actions to be elaborated at freeze time.
3956 if Is_Tagged_Type
(Etype
(P
))
3957 and then In_Open_Scopes
(Scope
(Etype
(P
)))
3959 Ensure_Freeze_Node
(Etype
(P
));
3960 Append_Freeze_Action
(Etype
(P
), Body_Node
);
3962 Rewrite
(N
, Body_Node
);
3964 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3968 -- Generic formal subprograms or AST_Handler renaming
3971 Rewrite
(N
, Body_Node
);
3973 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3976 if Is_Compilation_Unit
(New_S
) then
3978 ("a library unit can only rename another library unit", N
);
3981 -- We suppress elaboration warnings for the resulting entity, since
3982 -- clearly they are not needed, and more particularly, in the case
3983 -- of a generic formal subprogram, the resulting entity can appear
3984 -- after the instantiation itself, and thus look like a bogus case
3985 -- of access before elaboration.
3987 Set_Suppress_Elaboration_Warnings
(New_S
);
3989 end Attribute_Renaming
;
3991 ----------------------
3992 -- Chain_Use_Clause --
3993 ----------------------
3995 procedure Chain_Use_Clause
(N
: Node_Id
) is
3997 Level
: Int
:= Scope_Stack
.Last
;
4000 if not Is_Compilation_Unit
(Current_Scope
)
4001 or else not Is_Child_Unit
(Current_Scope
)
4003 null; -- Common case
4005 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
4006 null; -- Common case for compilation unit
4009 -- If declaration appears in some other scope, it must be in some
4010 -- parent unit when compiling a child.
4012 Pack
:= Defining_Entity
(Parent
(N
));
4013 if not In_Open_Scopes
(Pack
) then
4014 null; -- default as well
4016 -- If the use clause appears in an ancestor and we are in the
4017 -- private part of the immediate parent, the use clauses are
4018 -- already installed.
4020 elsif Pack
/= Scope
(Current_Scope
)
4021 and then In_Private_Part
(Scope
(Current_Scope
))
4026 -- Find entry for parent unit in scope stack
4028 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4034 Set_Next_Use_Clause
(N
,
4035 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4036 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4037 end Chain_Use_Clause
;
4039 ---------------------------
4040 -- Check_Frozen_Renaming --
4041 ---------------------------
4043 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4048 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4051 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4053 if Is_Entity_Name
(Name
(N
)) then
4054 Old_S
:= Entity
(Name
(N
));
4056 if not Is_Frozen
(Old_S
)
4057 and then Operating_Mode
/= Check_Semantics
4059 Append_Freeze_Action
(Old_S
, B_Node
);
4061 Insert_After
(N
, B_Node
);
4065 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4067 ("subprogram used in renaming_as_body cannot be intrinsic",
4072 Insert_After
(N
, B_Node
);
4076 end Check_Frozen_Renaming
;
4078 -------------------------------
4079 -- Set_Entity_Or_Discriminal --
4080 -------------------------------
4082 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4086 -- If the entity is not a discriminant, or else expansion is disabled,
4087 -- simply set the entity.
4089 if not In_Spec_Expression
4090 or else Ekind
(E
) /= E_Discriminant
4091 or else Inside_A_Generic
4093 Set_Entity_With_Checks
(N
, E
);
4095 -- The replacement of a discriminant by the corresponding discriminal
4096 -- is not done for a task discriminant that appears in a default
4097 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4098 -- for details on their handling.
4100 elsif Is_Concurrent_Type
(Scope
(E
)) then
4103 and then not Nkind_In
(P
, N_Parameter_Specification
,
4104 N_Component_Declaration
)
4110 and then Nkind
(P
) = N_Parameter_Specification
4115 Set_Entity
(N
, Discriminal
(E
));
4118 -- Otherwise, this is a discriminant in a context in which
4119 -- it is a reference to the corresponding parameter of the
4120 -- init proc for the enclosing type.
4123 Set_Entity
(N
, Discriminal
(E
));
4125 end Set_Entity_Or_Discriminal
;
4127 -----------------------------------
4128 -- Check_In_Previous_With_Clause --
4129 -----------------------------------
4131 procedure Check_In_Previous_With_Clause
4135 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4140 Item
:= First
(Context_Items
(Parent
(N
)));
4141 while Present
(Item
) and then Item
/= N
loop
4142 if Nkind
(Item
) = N_With_Clause
4144 -- Protect the frontend against previous critical errors
4146 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4147 and then Entity
(Name
(Item
)) = Pack
4151 -- Find root library unit in with_clause
4153 while Nkind
(Par
) = N_Expanded_Name
loop
4154 Par
:= Prefix
(Par
);
4157 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4158 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4167 -- On exit, package is not mentioned in a previous with_clause.
4168 -- Check if its prefix is.
4170 if Nkind
(Nam
) = N_Expanded_Name
then
4171 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4173 elsif Pack
/= Any_Id
then
4174 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4176 end Check_In_Previous_With_Clause
;
4178 ---------------------------------
4179 -- Check_Library_Unit_Renaming --
4180 ---------------------------------
4182 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4186 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4189 -- Check for library unit. Note that we used to check for the scope
4190 -- being Standard here, but that was wrong for Standard itself.
4192 elsif not Is_Compilation_Unit
(Old_E
)
4193 and then not Is_Child_Unit
(Old_E
)
4195 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4197 -- Entities defined in Standard (operators and boolean literals) cannot
4198 -- be renamed as library units.
4200 elsif Scope
(Old_E
) = Standard_Standard
4201 and then Sloc
(Old_E
) = Standard_Location
4203 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4205 elsif Present
(Parent_Spec
(N
))
4206 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4207 and then not Is_Child_Unit
(Old_E
)
4210 ("renamed unit must be a child unit of generic parent", Name
(N
));
4212 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4213 and then Nkind
(Name
(N
)) = N_Expanded_Name
4214 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4215 and then Is_Generic_Unit
(Old_E
)
4218 ("renamed generic unit must be a library unit", Name
(N
));
4220 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4222 -- Inherit categorization flags
4224 New_E
:= Defining_Entity
(N
);
4225 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4226 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4227 Set_Is_Remote_Call_Interface
(New_E
,
4228 Is_Remote_Call_Interface
(Old_E
));
4229 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4230 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4232 end Check_Library_Unit_Renaming
;
4234 ------------------------
4235 -- Enclosing_Instance --
4236 ------------------------
4238 function Enclosing_Instance
return Entity_Id
is
4242 if not Is_Generic_Instance
(Current_Scope
) then
4246 S
:= Scope
(Current_Scope
);
4247 while S
/= Standard_Standard
loop
4248 if Is_Generic_Instance
(S
) then
4256 end Enclosing_Instance
;
4262 procedure End_Scope
is
4268 Id
:= First_Entity
(Current_Scope
);
4269 while Present
(Id
) loop
4270 -- An entity in the current scope is not necessarily the first one
4271 -- on its homonym chain. Find its predecessor if any,
4272 -- If it is an internal entity, it will not be in the visibility
4273 -- chain altogether, and there is nothing to unchain.
4275 if Id
/= Current_Entity
(Id
) then
4276 Prev
:= Current_Entity
(Id
);
4277 while Present
(Prev
)
4278 and then Present
(Homonym
(Prev
))
4279 and then Homonym
(Prev
) /= Id
4281 Prev
:= Homonym
(Prev
);
4284 -- Skip to end of loop if Id is not in the visibility chain
4286 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4294 Set_Is_Immediately_Visible
(Id
, False);
4296 Outer
:= Homonym
(Id
);
4297 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4298 Outer
:= Homonym
(Outer
);
4301 -- Reset homonym link of other entities, but do not modify link
4302 -- between entities in current scope, so that the back-end can have
4303 -- a proper count of local overloadings.
4306 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4308 elsif Scope
(Prev
) /= Scope
(Id
) then
4309 Set_Homonym
(Prev
, Outer
);
4316 -- If the scope generated freeze actions, place them before the
4317 -- current declaration and analyze them. Type declarations and
4318 -- the bodies of initialization procedures can generate such nodes.
4319 -- We follow the parent chain until we reach a list node, which is
4320 -- the enclosing list of declarations. If the list appears within
4321 -- a protected definition, move freeze nodes outside the protected
4325 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4329 L
: constant List_Id
:= Scope_Stack
.Table
4330 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4333 if Is_Itype
(Current_Scope
) then
4334 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4336 Decl
:= Parent
(Current_Scope
);
4341 while not (Is_List_Member
(Decl
))
4342 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4345 Decl
:= Parent
(Decl
);
4348 Insert_List_Before_And_Analyze
(Decl
, L
);
4356 ---------------------
4357 -- End_Use_Clauses --
4358 ---------------------
4360 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4364 -- Remove Use_Type clauses first, because they affect the
4365 -- visibility of operators in subsequent used packages.
4368 while Present
(U
) loop
4369 if Nkind
(U
) = N_Use_Type_Clause
then
4373 Next_Use_Clause
(U
);
4377 while Present
(U
) loop
4378 if Nkind
(U
) = N_Use_Package_Clause
then
4379 End_Use_Package
(U
);
4382 Next_Use_Clause
(U
);
4384 end End_Use_Clauses
;
4386 ---------------------
4387 -- End_Use_Package --
4388 ---------------------
4390 procedure End_Use_Package
(N
: Node_Id
) is
4391 Pack_Name
: Node_Id
;
4396 function Is_Primitive_Operator_In_Use
4398 F
: Entity_Id
) return Boolean;
4399 -- Check whether Op is a primitive operator of a use-visible type
4401 ----------------------------------
4402 -- Is_Primitive_Operator_In_Use --
4403 ----------------------------------
4405 function Is_Primitive_Operator_In_Use
4407 F
: Entity_Id
) return Boolean
4409 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4411 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4412 end Is_Primitive_Operator_In_Use
;
4414 -- Start of processing for End_Use_Package
4417 Pack_Name
:= First
(Names
(N
));
4418 while Present
(Pack_Name
) loop
4420 -- Test that Pack_Name actually denotes a package before processing
4422 if Is_Entity_Name
(Pack_Name
)
4423 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4425 Pack
:= Entity
(Pack_Name
);
4427 if In_Open_Scopes
(Pack
) then
4430 elsif not Redundant_Use
(Pack_Name
) then
4431 Set_In_Use
(Pack
, False);
4432 Set_Current_Use_Clause
(Pack
, Empty
);
4434 Id
:= First_Entity
(Pack
);
4435 while Present
(Id
) loop
4437 -- Preserve use-visibility of operators that are primitive
4438 -- operators of a type that is use-visible through an active
4441 if Nkind
(Id
) = N_Defining_Operator_Symbol
4443 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4445 (Present
(Next_Formal
(First_Formal
(Id
)))
4447 Is_Primitive_Operator_In_Use
4448 (Id
, Next_Formal
(First_Formal
(Id
)))))
4452 Set_Is_Potentially_Use_Visible
(Id
, False);
4455 if Is_Private_Type
(Id
)
4456 and then Present
(Full_View
(Id
))
4458 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4464 if Present
(Renamed_Object
(Pack
)) then
4465 Set_In_Use
(Renamed_Object
(Pack
), False);
4466 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4469 if Chars
(Pack
) = Name_System
4470 and then Scope
(Pack
) = Standard_Standard
4471 and then Present_System_Aux
4473 Id
:= First_Entity
(System_Aux_Id
);
4474 while Present
(Id
) loop
4475 Set_Is_Potentially_Use_Visible
(Id
, False);
4477 if Is_Private_Type
(Id
)
4478 and then Present
(Full_View
(Id
))
4480 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4486 Set_In_Use
(System_Aux_Id
, False);
4490 Set_Redundant_Use
(Pack_Name
, False);
4497 if Present
(Hidden_By_Use_Clause
(N
)) then
4498 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4499 while Present
(Elmt
) loop
4501 E
: constant Entity_Id
:= Node
(Elmt
);
4504 -- Reset either Use_Visibility or Direct_Visibility, depending
4505 -- on how the entity was hidden by the use clause.
4507 if In_Use
(Scope
(E
))
4508 and then Used_As_Generic_Actual
(Scope
(E
))
4510 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4512 Set_Is_Immediately_Visible
(Node
(Elmt
));
4519 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4521 end End_Use_Package
;
4527 procedure End_Use_Type
(N
: Node_Id
) is
4532 -- Start of processing for End_Use_Type
4535 Id
:= First
(Subtype_Marks
(N
));
4536 while Present
(Id
) loop
4538 -- A call to Rtsfind may occur while analyzing a use_type clause,
4539 -- in which case the type marks are not resolved yet, and there is
4540 -- nothing to remove.
4542 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4548 if T
= Any_Type
or else From_Limited_With
(T
) then
4551 -- Note that the use_type clause may mention a subtype of the type
4552 -- whose primitive operations have been made visible. Here as
4553 -- elsewhere, it is the base type that matters for visibility.
4555 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4558 elsif not Redundant_Use
(Id
) then
4559 Set_In_Use
(T
, False);
4560 Set_In_Use
(Base_Type
(T
), False);
4561 Set_Current_Use_Clause
(T
, Empty
);
4562 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4569 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4573 Elmt
:= First_Elmt
(Used_Operations
(N
));
4574 while Present
(Elmt
) loop
4575 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4581 ----------------------
4582 -- Find_Direct_Name --
4583 ----------------------
4585 procedure Find_Direct_Name
(N
: Node_Id
) is
4590 Inst
: Entity_Id
:= Empty
;
4591 -- Enclosing instance, if any
4593 Homonyms
: Entity_Id
;
4594 -- Saves start of homonym chain
4596 Nvis_Entity
: Boolean;
4597 -- Set True to indicate that there is at least one entity on the homonym
4598 -- chain which, while not visible, is visible enough from the user point
4599 -- of view to warrant an error message of "not visible" rather than
4602 Nvis_Is_Private_Subprg
: Boolean := False;
4603 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4604 -- effect concerning library subprograms has been detected. Used to
4605 -- generate the precise error message.
4607 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4608 -- Returns true if the entity is an actual for a package that is itself
4609 -- an actual for a formal package of the current instance. Such an
4610 -- entity requires special handling because it may be use-visible but
4611 -- hides directly visible entities defined outside the instance, because
4612 -- the corresponding formal did so in the generic.
4614 function Is_Actual_Parameter
return Boolean;
4615 -- This function checks if the node N is an identifier that is an actual
4616 -- parameter of a procedure call. If so it returns True, otherwise it
4617 -- return False. The reason for this check is that at this stage we do
4618 -- not know what procedure is being called if the procedure might be
4619 -- overloaded, so it is premature to go setting referenced flags or
4620 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4621 -- for that processing
4623 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4624 -- This function determines whether a reference to the entity E, which
4625 -- is not visible, can reasonably be considered to be known to the
4626 -- writer of the reference. This is a heuristic test, used only for
4627 -- the purposes of figuring out whether we prefer to complain that an
4628 -- entity is undefined or invisible (and identify the declaration of
4629 -- the invisible entity in the latter case). The point here is that we
4630 -- don't want to complain that something is invisible and then point to
4631 -- something entirely mysterious to the writer.
4633 procedure Nvis_Messages
;
4634 -- Called if there are no visible entries for N, but there is at least
4635 -- one non-directly visible, or hidden declaration. This procedure
4636 -- outputs an appropriate set of error messages.
4638 procedure Undefined
(Nvis
: Boolean);
4639 -- This function is called if the current node has no corresponding
4640 -- visible entity or entities. The value set in Msg indicates whether
4641 -- an error message was generated (multiple error messages for the
4642 -- same variable are generally suppressed, see body for details).
4643 -- Msg is True if an error message was generated, False if not. This
4644 -- value is used by the caller to determine whether or not to output
4645 -- additional messages where appropriate. The parameter is set False
4646 -- to get the message "X is undefined", and True to get the message
4647 -- "X is not visible".
4649 -------------------------
4650 -- From_Actual_Package --
4651 -------------------------
4653 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4654 Scop
: constant Entity_Id
:= Scope
(E
);
4655 -- Declared scope of candidate entity
4659 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4660 -- Recursive function that does the work and examines actuals of
4661 -- actual packages of current instance.
4663 ------------------------
4664 -- Declared_In_Actual --
4665 ------------------------
4667 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4671 if No
(Associated_Formal_Package
(Pack
)) then
4675 Act
:= First_Entity
(Pack
);
4676 while Present
(Act
) loop
4677 if Renamed_Object
(Pack
) = Scop
then
4680 -- Check for end of list of actuals.
4682 elsif Ekind
(Act
) = E_Package
4683 and then Renamed_Object
(Act
) = Pack
4687 elsif Ekind
(Act
) = E_Package
4688 and then Declared_In_Actual
(Act
)
4698 end Declared_In_Actual
;
4700 -- Start of processing for From_Actual_Package
4703 if not In_Instance
then
4707 Inst
:= Current_Scope
;
4708 while Present
(Inst
)
4709 and then Ekind
(Inst
) /= E_Package
4710 and then not Is_Generic_Instance
(Inst
)
4712 Inst
:= Scope
(Inst
);
4719 Act
:= First_Entity
(Inst
);
4720 while Present
(Act
) loop
4721 if Ekind
(Act
) = E_Package
4722 and then Declared_In_Actual
(Act
)
4732 end From_Actual_Package
;
4734 -------------------------
4735 -- Is_Actual_Parameter --
4736 -------------------------
4738 function Is_Actual_Parameter
return Boolean is
4741 Nkind
(N
) = N_Identifier
4743 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4745 (Nkind
(Parent
(N
)) = N_Parameter_Association
4746 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4747 and then Nkind
(Parent
(Parent
(N
))) =
4748 N_Procedure_Call_Statement
));
4749 end Is_Actual_Parameter
;
4751 -------------------------
4752 -- Known_But_Invisible --
4753 -------------------------
4755 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4756 Fname
: File_Name_Type
;
4759 -- Entities in Standard are always considered to be known
4761 if Sloc
(E
) <= Standard_Location
then
4764 -- An entity that does not come from source is always considered
4765 -- to be unknown, since it is an artifact of code expansion.
4767 elsif not Comes_From_Source
(E
) then
4770 -- In gnat internal mode, we consider all entities known. The
4771 -- historical reason behind this discrepancy is not known??? But the
4772 -- only effect is to modify the error message given, so it is not
4773 -- critical. Since it only affects the exact wording of error
4774 -- messages in illegal programs, we do not mention this as an
4775 -- effect of -gnatg, since it is not a language modification.
4777 elsif GNAT_Mode
then
4781 -- Here we have an entity that is not from package Standard, and
4782 -- which comes from Source. See if it comes from an internal file.
4784 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4786 -- Case of from internal file
4788 if Is_Internal_File_Name
(Fname
) then
4790 -- Private part entities in internal files are never considered
4791 -- to be known to the writer of normal application code.
4793 if Is_Hidden
(E
) then
4797 -- Entities from System packages other than System and
4798 -- System.Storage_Elements are not considered to be known.
4799 -- System.Auxxxx files are also considered known to the user.
4801 -- Should refine this at some point to generally distinguish
4802 -- between known and unknown internal files ???
4804 Get_Name_String
(Fname
);
4809 Name_Buffer
(1 .. 2) /= "s-"
4811 Name_Buffer
(3 .. 8) = "stoele"
4813 Name_Buffer
(3 .. 5) = "aux";
4815 -- If not an internal file, then entity is definitely known, even if
4816 -- it is in a private part (the message generated will note that it
4817 -- is in a private part).
4822 end Known_But_Invisible
;
4828 procedure Nvis_Messages
is
4829 Comp_Unit
: Node_Id
;
4831 Found
: Boolean := False;
4832 Hidden
: Boolean := False;
4836 -- Ada 2005 (AI-262): Generate a precise error concerning the
4837 -- Beaujolais effect that was previously detected
4839 if Nvis_Is_Private_Subprg
then
4841 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4842 and then Ekind
(E2
) = E_Function
4843 and then Scope
(E2
) = Standard_Standard
4844 and then Has_Private_With
(E2
));
4846 -- Find the sloc corresponding to the private with'ed unit
4848 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4849 Error_Msg_Sloc
:= No_Location
;
4851 Item
:= First
(Context_Items
(Comp_Unit
));
4852 while Present
(Item
) loop
4853 if Nkind
(Item
) = N_With_Clause
4854 and then Private_Present
(Item
)
4855 and then Entity
(Name
(Item
)) = E2
4857 Error_Msg_Sloc
:= Sloc
(Item
);
4864 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4866 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4870 Undefined
(Nvis
=> True);
4874 -- First loop does hidden declarations
4877 while Present
(Ent
) loop
4878 if Is_Potentially_Use_Visible
(Ent
) then
4880 Error_Msg_N
-- CODEFIX
4881 ("multiple use clauses cause hiding!", N
);
4885 Error_Msg_Sloc
:= Sloc
(Ent
);
4886 Error_Msg_N
-- CODEFIX
4887 ("hidden declaration#!", N
);
4890 Ent
:= Homonym
(Ent
);
4893 -- If we found hidden declarations, then that's enough, don't
4894 -- bother looking for non-visible declarations as well.
4900 -- Second loop does non-directly visible declarations
4903 while Present
(Ent
) loop
4904 if not Is_Potentially_Use_Visible
(Ent
) then
4906 -- Do not bother the user with unknown entities
4908 if not Known_But_Invisible
(Ent
) then
4912 Error_Msg_Sloc
:= Sloc
(Ent
);
4914 -- Output message noting that there is a non-visible
4915 -- declaration, distinguishing the private part case.
4917 if Is_Hidden
(Ent
) then
4918 Error_Msg_N
("non-visible (private) declaration#!", N
);
4920 -- If the entity is declared in a generic package, it
4921 -- cannot be visible, so there is no point in adding it
4922 -- to the list of candidates if another homograph from a
4923 -- non-generic package has been seen.
4925 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4931 Error_Msg_N
-- CODEFIX
4932 ("non-visible declaration#!", N
);
4934 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
4938 if Is_Compilation_Unit
(Ent
)
4940 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
4942 Error_Msg_Qual_Level
:= 99;
4943 Error_Msg_NE
-- CODEFIX
4944 ("\\missing `WITH &;`", N
, Ent
);
4945 Error_Msg_Qual_Level
:= 0;
4948 if Ekind
(Ent
) = E_Discriminant
4949 and then Present
(Corresponding_Discriminant
(Ent
))
4950 and then Scope
(Corresponding_Discriminant
(Ent
)) =
4954 ("inherited discriminant not allowed here" &
4955 " (RM 3.8 (12), 3.8.1 (6))!", N
);
4959 -- Set entity and its containing package as referenced. We
4960 -- can't be sure of this, but this seems a better choice
4961 -- to avoid unused entity messages.
4963 if Comes_From_Source
(Ent
) then
4964 Set_Referenced
(Ent
);
4965 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
4970 Ent
:= Homonym
(Ent
);
4979 procedure Undefined
(Nvis
: Boolean) is
4980 Emsg
: Error_Msg_Id
;
4983 -- We should never find an undefined internal name. If we do, then
4984 -- see if we have previous errors. If so, ignore on the grounds that
4985 -- it is probably a cascaded message (e.g. a block label from a badly
4986 -- formed block). If no previous errors, then we have a real internal
4987 -- error of some kind so raise an exception.
4989 if Is_Internal_Name
(Chars
(N
)) then
4990 if Total_Errors_Detected
/= 0 then
4993 raise Program_Error
;
4997 -- A very specialized error check, if the undefined variable is
4998 -- a case tag, and the case type is an enumeration type, check
4999 -- for a possible misspelling, and if so, modify the identifier
5001 -- Named aggregate should also be handled similarly ???
5003 if Nkind
(N
) = N_Identifier
5004 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
5007 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5008 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5013 if Is_Enumeration_Type
(Case_Typ
)
5014 and then not Is_Standard_Character_Type
(Case_Typ
)
5016 Lit
:= First_Literal
(Case_Typ
);
5017 Get_Name_String
(Chars
(Lit
));
5019 if Chars
(Lit
) /= Chars
(N
)
5020 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5022 Error_Msg_Node_2
:= Lit
;
5023 Error_Msg_N
-- CODEFIX
5024 ("& is undefined, assume misspelling of &", N
);
5025 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5029 Lit
:= Next_Literal
(Lit
);
5034 -- Normal processing
5036 Set_Entity
(N
, Any_Id
);
5037 Set_Etype
(N
, Any_Type
);
5039 -- We use the table Urefs to keep track of entities for which we
5040 -- have issued errors for undefined references. Multiple errors
5041 -- for a single name are normally suppressed, however we modify
5042 -- the error message to alert the programmer to this effect.
5044 for J
in Urefs
.First
.. Urefs
.Last
loop
5045 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5046 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5047 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5049 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5051 if Urefs
.Table
(J
).Nvis
then
5052 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5053 "& is not visible (more references follow)");
5055 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5056 "& is undefined (more references follow)");
5059 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5062 -- Although we will set Msg False, and thus suppress the
5063 -- message, we also set Error_Posted True, to avoid any
5064 -- cascaded messages resulting from the undefined reference.
5067 Set_Error_Posted
(N
, True);
5072 -- If entry not found, this is first undefined occurrence
5075 Error_Msg_N
("& is not visible!", N
);
5079 Error_Msg_N
("& is undefined!", N
);
5082 -- A very bizarre special check, if the undefined identifier
5083 -- is put or put_line, then add a special error message (since
5084 -- this is a very common error for beginners to make).
5086 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5087 Error_Msg_N
-- CODEFIX
5088 ("\\possible missing `WITH Ada.Text_'I'O; " &
5089 "USE Ada.Text_'I'O`!", N
);
5091 -- Another special check if N is the prefix of a selected
5092 -- component which is a known unit, add message complaining
5093 -- about missing with for this unit.
5095 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5096 and then N
= Prefix
(Parent
(N
))
5097 and then Is_Known_Unit
(Parent
(N
))
5099 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5100 Error_Msg_N
-- CODEFIX
5101 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5104 -- Now check for possible misspellings
5108 Ematch
: Entity_Id
:= Empty
;
5110 Last_Name_Id
: constant Name_Id
:=
5111 Name_Id
(Nat
(First_Name_Id
) +
5112 Name_Entries_Count
- 1);
5115 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5116 E
:= Get_Name_Entity_Id
(Nam
);
5119 and then (Is_Immediately_Visible
(E
)
5121 Is_Potentially_Use_Visible
(E
))
5123 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5130 if Present
(Ematch
) then
5131 Error_Msg_NE
-- CODEFIX
5132 ("\possible misspelling of&", N
, Ematch
);
5137 -- Make entry in undefined references table unless the full errors
5138 -- switch is set, in which case by refraining from generating the
5139 -- table entry, we guarantee that we get an error message for every
5140 -- undefined reference.
5142 if not All_Errors_Mode
then
5153 -- Start of processing for Find_Direct_Name
5156 -- If the entity pointer is already set, this is an internal node, or
5157 -- a node that is analyzed more than once, after a tree modification.
5158 -- In such a case there is no resolution to perform, just set the type.
5160 if Present
(Entity
(N
)) then
5161 if Is_Type
(Entity
(N
)) then
5162 Set_Etype
(N
, Entity
(N
));
5166 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5169 -- One special case here. If the Etype field is already set,
5170 -- and references the packed array type corresponding to the
5171 -- etype of the referenced entity, then leave it alone. This
5172 -- happens for trees generated from Exp_Pakd, where expressions
5173 -- can be deliberately "mis-typed" to the packed array type.
5175 if Is_Array_Type
(Entyp
)
5176 and then Is_Packed
(Entyp
)
5177 and then Present
(Etype
(N
))
5178 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5182 -- If not that special case, then just reset the Etype
5185 Set_Etype
(N
, Etype
(Entity
(N
)));
5193 -- Here if Entity pointer was not set, we need full visibility analysis
5194 -- First we generate debugging output if the debug E flag is set.
5196 if Debug_Flag_E
then
5197 Write_Str
("Looking for ");
5198 Write_Name
(Chars
(N
));
5202 Homonyms
:= Current_Entity
(N
);
5203 Nvis_Entity
:= False;
5206 while Present
(E
) loop
5208 -- If entity is immediately visible or potentially use visible, then
5209 -- process the entity and we are done.
5211 if Is_Immediately_Visible
(E
) then
5212 goto Immediately_Visible_Entity
;
5214 elsif Is_Potentially_Use_Visible
(E
) then
5215 goto Potentially_Use_Visible_Entity
;
5217 -- Note if a known but invisible entity encountered
5219 elsif Known_But_Invisible
(E
) then
5220 Nvis_Entity
:= True;
5223 -- Move to next entity in chain and continue search
5228 -- If no entries on homonym chain that were potentially visible,
5229 -- and no entities reasonably considered as non-visible, then
5230 -- we have a plain undefined reference, with no additional
5231 -- explanation required.
5233 if not Nvis_Entity
then
5234 Undefined
(Nvis
=> False);
5236 -- Otherwise there is at least one entry on the homonym chain that
5237 -- is reasonably considered as being known and non-visible.
5245 -- Processing for a potentially use visible entry found. We must search
5246 -- the rest of the homonym chain for two reasons. First, if there is a
5247 -- directly visible entry, then none of the potentially use-visible
5248 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5249 -- for the case of multiple potentially use-visible entries hiding one
5250 -- another and as a result being non-directly visible (RM 8.4(11)).
5252 <<Potentially_Use_Visible_Entity
>> declare
5253 Only_One_Visible
: Boolean := True;
5254 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5258 while Present
(E2
) loop
5259 if Is_Immediately_Visible
(E2
) then
5261 -- If the use-visible entity comes from the actual for a
5262 -- formal package, it hides a directly visible entity from
5263 -- outside the instance.
5265 if From_Actual_Package
(E
)
5266 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5271 goto Immediately_Visible_Entity
;
5274 elsif Is_Potentially_Use_Visible
(E2
) then
5275 Only_One_Visible
:= False;
5276 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5278 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5279 -- that can occur in private_with clauses. Example:
5282 -- private with B; package A is
5283 -- package C is function B return Integer;
5285 -- V1 : Integer := B;
5286 -- private function B return Integer;
5287 -- V2 : Integer := B;
5290 -- V1 resolves to A.B, but V2 resolves to library unit B
5292 elsif Ekind
(E2
) = E_Function
5293 and then Scope
(E2
) = Standard_Standard
5294 and then Has_Private_With
(E2
)
5296 Only_One_Visible
:= False;
5297 All_Overloadable
:= False;
5298 Nvis_Is_Private_Subprg
:= True;
5305 -- On falling through this loop, we have checked that there are no
5306 -- immediately visible entities. Only_One_Visible is set if exactly
5307 -- one potentially use visible entity exists. All_Overloadable is
5308 -- set if all the potentially use visible entities are overloadable.
5309 -- The condition for legality is that either there is one potentially
5310 -- use visible entity, or if there is more than one, then all of them
5311 -- are overloadable.
5313 if Only_One_Visible
or All_Overloadable
then
5316 -- If there is more than one potentially use-visible entity and at
5317 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5318 -- Note that E points to the first such entity on the homonym list.
5319 -- Special case: if one of the entities is declared in an actual
5320 -- package, it was visible in the generic, and takes precedence over
5321 -- other entities that are potentially use-visible. Same if it is
5322 -- declared in a local instantiation of the current instance.
5327 -- Find current instance
5329 Inst
:= Current_Scope
;
5330 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5331 if Is_Generic_Instance
(Inst
) then
5335 Inst
:= Scope
(Inst
);
5339 while Present
(E2
) loop
5340 if From_Actual_Package
(E2
)
5342 (Is_Generic_Instance
(Scope
(E2
))
5343 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5356 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5358 -- A use-clause in the body of a system file creates conflict
5359 -- with some entity in a user scope, while rtsfind is active.
5360 -- Keep only the entity coming from another predefined unit.
5363 while Present
(E2
) loop
5364 if Is_Predefined_File_Name
5365 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5374 -- Entity must exist because predefined unit is correct
5376 raise Program_Error
;
5385 -- Come here with E set to the first immediately visible entity on
5386 -- the homonym chain. This is the one we want unless there is another
5387 -- immediately visible entity further on in the chain for an inner
5388 -- scope (RM 8.3(8)).
5390 <<Immediately_Visible_Entity
>> declare
5395 -- Find scope level of initial entity. When compiling through
5396 -- Rtsfind, the previous context is not completely invisible, and
5397 -- an outer entity may appear on the chain, whose scope is below
5398 -- the entry for Standard that delimits the current scope stack.
5399 -- Indicate that the level for this spurious entry is outside of
5400 -- the current scope stack.
5402 Level
:= Scope_Stack
.Last
;
5404 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5405 exit when Scop
= Scope
(E
);
5407 exit when Scop
= Standard_Standard
;
5410 -- Now search remainder of homonym chain for more inner entry
5411 -- If the entity is Standard itself, it has no scope, and we
5412 -- compare it with the stack entry directly.
5415 while Present
(E2
) loop
5416 if Is_Immediately_Visible
(E2
) then
5418 -- If a generic package contains a local declaration that
5419 -- has the same name as the generic, there may be a visibility
5420 -- conflict in an instance, where the local declaration must
5421 -- also hide the name of the corresponding package renaming.
5422 -- We check explicitly for a package declared by a renaming,
5423 -- whose renamed entity is an instance that is on the scope
5424 -- stack, and that contains a homonym in the same scope. Once
5425 -- we have found it, we know that the package renaming is not
5426 -- immediately visible, and that the identifier denotes the
5427 -- other entity (and its homonyms if overloaded).
5429 if Scope
(E
) = Scope
(E2
)
5430 and then Ekind
(E
) = E_Package
5431 and then Present
(Renamed_Object
(E
))
5432 and then Is_Generic_Instance
(Renamed_Object
(E
))
5433 and then In_Open_Scopes
(Renamed_Object
(E
))
5434 and then Comes_From_Source
(N
)
5436 Set_Is_Immediately_Visible
(E
, False);
5440 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5441 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5442 or else Scope_Stack
.Table
(J
).Entity
= E2
5455 -- At the end of that loop, E is the innermost immediately
5456 -- visible entity, so we are all set.
5459 -- Come here with entity found, and stored in E
5463 -- Check violation of No_Wide_Characters restriction
5465 Check_Wide_Character_Restriction
(E
, N
);
5467 -- When distribution features are available (Get_PCS_Name /=
5468 -- Name_No_DSA), a remote access-to-subprogram type is converted
5469 -- into a record type holding whatever information is needed to
5470 -- perform a remote call on an RCI subprogram. In that case we
5471 -- rewrite any occurrence of the RAS type into the equivalent record
5472 -- type here. 'Access attribute references and RAS dereferences are
5473 -- then implemented using specific TSSs. However when distribution is
5474 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5475 -- generation of these TSSs, and we must keep the RAS type in its
5476 -- original access-to-subprogram form (since all calls through a
5477 -- value of such type will be local anyway in the absence of a PCS).
5479 if Comes_From_Source
(N
)
5480 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5481 and then Ekind
(E
) = E_Access_Subprogram_Type
5482 and then Expander_Active
5483 and then Get_PCS_Name
/= Name_No_DSA
5485 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5489 -- Set the entity. Note that the reason we call Set_Entity for the
5490 -- overloadable case, as opposed to Set_Entity_With_Checks is
5491 -- that in the overloaded case, the initial call can set the wrong
5492 -- homonym. The call that sets the right homonym is in Sem_Res and
5493 -- that call does use Set_Entity_With_Checks, so we don't miss
5496 if Is_Overloadable
(E
) then
5499 Set_Entity_With_Checks
(N
, E
);
5505 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5508 if Debug_Flag_E
then
5509 Write_Str
(" found ");
5510 Write_Entity_Info
(E
, " ");
5513 -- If the Ekind of the entity is Void, it means that all homonyms
5514 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5515 -- test is skipped if the current scope is a record and the name is
5516 -- a pragma argument expression (case of Atomic and Volatile pragmas
5517 -- and possibly other similar pragmas added later, which are allowed
5518 -- to reference components in the current record).
5520 if Ekind
(E
) = E_Void
5522 (not Is_Record_Type
(Current_Scope
)
5523 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5525 Premature_Usage
(N
);
5527 -- If the entity is overloadable, collect all interpretations of the
5528 -- name for subsequent overload resolution. We optimize a bit here to
5529 -- do this only if we have an overloadable entity that is not on its
5530 -- own on the homonym chain.
5532 elsif Is_Overloadable
(E
)
5533 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5535 Collect_Interps
(N
);
5537 -- If no homonyms were visible, the entity is unambiguous
5539 if not Is_Overloaded
(N
) then
5540 if not Is_Actual_Parameter
then
5541 Generate_Reference
(E
, N
);
5545 -- Case of non-overloadable entity, set the entity providing that
5546 -- we do not have the case of a discriminant reference within a
5547 -- default expression. Such references are replaced with the
5548 -- corresponding discriminal, which is the formal corresponding to
5549 -- to the discriminant in the initialization procedure.
5552 -- Entity is unambiguous, indicate that it is referenced here
5554 -- For a renaming of an object, always generate simple reference,
5555 -- we don't try to keep track of assignments in this case, except
5556 -- in SPARK mode where renamings are traversed for generating
5557 -- local effects of subprograms.
5560 and then Present
(Renamed_Object
(E
))
5561 and then not GNATprove_Mode
5563 Generate_Reference
(E
, N
);
5565 -- If the renamed entity is a private protected component,
5566 -- reference the original component as well. This needs to be
5567 -- done because the private renamings are installed before any
5568 -- analysis has occurred. Reference to a private component will
5569 -- resolve to the renaming and the original component will be
5570 -- left unreferenced, hence the following.
5572 if Is_Prival
(E
) then
5573 Generate_Reference
(Prival_Link
(E
), N
);
5576 -- One odd case is that we do not want to set the Referenced flag
5577 -- if the entity is a label, and the identifier is the label in
5578 -- the source, since this is not a reference from the point of
5579 -- view of the user.
5581 elsif Nkind
(Parent
(N
)) = N_Label
then
5583 R
: constant Boolean := Referenced
(E
);
5586 -- Generate reference unless this is an actual parameter
5587 -- (see comment below)
5589 if Is_Actual_Parameter
then
5590 Generate_Reference
(E
, N
);
5591 Set_Referenced
(E
, R
);
5595 -- Normal case, not a label: generate reference
5598 if not Is_Actual_Parameter
then
5600 -- Package or generic package is always a simple reference
5602 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5603 Generate_Reference
(E
, N
, 'r');
5605 -- Else see if we have a left hand side
5610 Generate_Reference
(E
, N
, 'm');
5613 Generate_Reference
(E
, N
, 'r');
5615 -- If we don't know now, generate reference later
5618 Deferred_References
.Append
((E
, N
));
5624 Set_Entity_Or_Discriminal
(N
, E
);
5626 -- The name may designate a generalized reference, in which case
5627 -- the dereference interpretation will be included. Context is
5628 -- one in which a name is legal.
5630 if Ada_Version
>= Ada_2012
5632 (Nkind
(Parent
(N
)) in N_Subexpr
5633 or else Nkind_In
(Parent
(N
), N_Assignment_Statement
,
5634 N_Object_Declaration
,
5635 N_Parameter_Association
))
5637 Check_Implicit_Dereference
(N
, Etype
(E
));
5642 -- Come here with entity set
5645 Check_Restriction_No_Use_Of_Entity
(N
);
5646 end Find_Direct_Name
;
5648 ------------------------
5649 -- Find_Expanded_Name --
5650 ------------------------
5652 -- This routine searches the homonym chain of the entity until it finds
5653 -- an entity declared in the scope denoted by the prefix. If the entity
5654 -- is private, it may nevertheless be immediately visible, if we are in
5655 -- the scope of its declaration.
5657 procedure Find_Expanded_Name
(N
: Node_Id
) is
5658 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean;
5659 -- Determine whether expanded name Nod appears within a pragma which is
5660 -- a suitable context for an abstract view of a state or variable. The
5661 -- following pragmas fall in this category:
5668 -- In addition, pragma Abstract_State is also considered suitable even
5669 -- though it is an illegal context for an abstract view as this allows
5670 -- for proper resolution of abstract views of variables. This illegal
5671 -- context is later flagged in the analysis of indicator Part_Of.
5673 -----------------------------
5674 -- In_Abstract_View_Pragma --
5675 -----------------------------
5677 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean is
5681 -- Climb the parent chain looking for a pragma
5684 while Present
(Par
) loop
5685 if Nkind
(Par
) = N_Pragma
then
5686 if Nam_In
(Pragma_Name
(Par
), Name_Abstract_State
,
5690 Name_Refined_Depends
,
5691 Name_Refined_Global
)
5695 -- Otherwise the pragma is not a legal context for an abstract
5702 -- Prevent the search from going too far
5704 elsif Is_Body_Or_Package_Declaration
(Par
) then
5708 Par
:= Parent
(Par
);
5712 end In_Abstract_View_Pragma
;
5716 Selector
: constant Node_Id
:= Selector_Name
(N
);
5717 Candidate
: Entity_Id
:= Empty
;
5721 -- Start of processing for Find_Expanded_Name
5724 P_Name
:= Entity
(Prefix
(N
));
5726 -- If the prefix is a renamed package, look for the entity in the
5727 -- original package.
5729 if Ekind
(P_Name
) = E_Package
5730 and then Present
(Renamed_Object
(P_Name
))
5732 P_Name
:= Renamed_Object
(P_Name
);
5734 -- Rewrite node with entity field pointing to renamed object
5736 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5737 Set_Entity
(Prefix
(N
), P_Name
);
5739 -- If the prefix is an object of a concurrent type, look for
5740 -- the entity in the associated task or protected type.
5742 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5743 P_Name
:= Etype
(P_Name
);
5746 Id
:= Current_Entity
(Selector
);
5749 Is_New_Candidate
: Boolean;
5752 while Present
(Id
) loop
5753 if Scope
(Id
) = P_Name
then
5755 Is_New_Candidate
:= True;
5757 -- Handle abstract views of states and variables. These are
5758 -- acceptable candidates only when the reference to the view
5759 -- appears in certain pragmas.
5761 if Ekind
(Id
) = E_Abstract_State
5762 and then From_Limited_With
(Id
)
5763 and then Present
(Non_Limited_View
(Id
))
5765 if In_Abstract_View_Pragma
(N
) then
5766 Candidate
:= Non_Limited_View
(Id
);
5767 Is_New_Candidate
:= True;
5769 -- Hide the candidate because it is not used in a proper
5774 Is_New_Candidate
:= False;
5778 -- Ada 2005 (AI-217): Handle shadow entities associated with
5779 -- types declared in limited-withed nested packages. We don't need
5780 -- to handle E_Incomplete_Subtype entities because the entities
5781 -- in the limited view are always E_Incomplete_Type and
5782 -- E_Class_Wide_Type entities (see Build_Limited_Views).
5784 -- Regarding the expression used to evaluate the scope, it
5785 -- is important to note that the limited view also has shadow
5786 -- entities associated nested packages. For this reason the
5787 -- correct scope of the entity is the scope of the real entity.
5788 -- The non-limited view may itself be incomplete, in which case
5789 -- get the full view if available.
5791 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
5792 and then From_Limited_With
(Id
)
5793 and then Present
(Non_Limited_View
(Id
))
5794 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5796 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5797 Is_New_Candidate
:= True;
5800 Is_New_Candidate
:= False;
5803 if Is_New_Candidate
then
5805 -- If entity is a child unit, either it is a visible child of
5806 -- the prefix, or we are in the body of a generic prefix, as
5807 -- will happen when a child unit is instantiated in the body
5808 -- of a generic parent. This is because the instance body does
5809 -- not restore the full compilation context, given that all
5810 -- non-local references have been captured.
5812 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5813 exit when Is_Visible_Lib_Unit
(Id
)
5814 or else (Is_Child_Unit
(Id
)
5815 and then In_Open_Scopes
(Scope
(Id
))
5816 and then In_Instance_Body
);
5818 exit when not Is_Hidden
(Id
);
5821 exit when Is_Immediately_Visible
(Id
);
5829 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5830 and then Is_Generic_Instance
(P_Name
)
5832 -- Expanded name denotes entity in (instance of) generic subprogram.
5833 -- The entity may be in the subprogram instance, or may denote one of
5834 -- the formals, which is declared in the enclosing wrapper package.
5836 P_Name
:= Scope
(P_Name
);
5838 Id
:= Current_Entity
(Selector
);
5839 while Present
(Id
) loop
5840 exit when Scope
(Id
) = P_Name
;
5845 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5846 Set_Etype
(N
, Any_Type
);
5848 -- If we are looking for an entity defined in System, try to find it
5849 -- in the child package that may have been provided as an extension
5850 -- to System. The Extend_System pragma will have supplied the name of
5851 -- the extension, which may have to be loaded.
5853 if Chars
(P_Name
) = Name_System
5854 and then Scope
(P_Name
) = Standard_Standard
5855 and then Present
(System_Extend_Unit
)
5856 and then Present_System_Aux
(N
)
5858 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5859 Find_Expanded_Name
(N
);
5862 -- There is an implicit instance of the predefined operator in
5863 -- the given scope. The operator entity is defined in Standard.
5864 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5866 elsif Nkind
(Selector
) = N_Operator_Symbol
5867 and then Has_Implicit_Operator
(N
)
5871 -- If there is no literal defined in the scope denoted by the
5872 -- prefix, the literal may belong to (a type derived from)
5873 -- Standard_Character, for which we have no explicit literals.
5875 elsif Nkind
(Selector
) = N_Character_Literal
5876 and then Has_Implicit_Character_Literal
(N
)
5881 -- If the prefix is a single concurrent object, use its name in
5882 -- the error message, rather than that of the anonymous type.
5884 if Is_Concurrent_Type
(P_Name
)
5885 and then Is_Internal_Name
(Chars
(P_Name
))
5887 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5889 Error_Msg_Node_2
:= P_Name
;
5892 if P_Name
= System_Aux_Id
then
5893 P_Name
:= Scope
(P_Name
);
5894 Set_Entity
(Prefix
(N
), P_Name
);
5897 if Present
(Candidate
) then
5899 -- If we know that the unit is a child unit we can give a more
5900 -- accurate error message.
5902 if Is_Child_Unit
(Candidate
) then
5904 -- If the candidate is a private child unit and we are in
5905 -- the visible part of a public unit, specialize the error
5906 -- message. There might be a private with_clause for it,
5907 -- but it is not currently active.
5909 if Is_Private_Descendant
(Candidate
)
5910 and then Ekind
(Current_Scope
) = E_Package
5911 and then not In_Private_Part
(Current_Scope
)
5912 and then not Is_Private_Descendant
(Current_Scope
)
5915 ("private child unit& is not visible here", Selector
);
5917 -- Normal case where we have a missing with for a child unit
5920 Error_Msg_Qual_Level
:= 99;
5921 Error_Msg_NE
-- CODEFIX
5922 ("missing `WITH &;`", Selector
, Candidate
);
5923 Error_Msg_Qual_Level
:= 0;
5926 -- Here we don't know that this is a child unit
5929 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5933 -- Within the instantiation of a child unit, the prefix may
5934 -- denote the parent instance, but the selector has the name
5935 -- of the original child. That is to say, when A.B appears
5936 -- within an instantiation of generic child unit B, the scope
5937 -- stack includes an instance of A (P_Name) and an instance
5938 -- of B under some other name. We scan the scope to find this
5939 -- child instance, which is the desired entity.
5940 -- Note that the parent may itself be a child instance, if
5941 -- the reference is of the form A.B.C, in which case A.B has
5942 -- already been rewritten with the proper entity.
5944 if In_Open_Scopes
(P_Name
)
5945 and then Is_Generic_Instance
(P_Name
)
5948 Gen_Par
: constant Entity_Id
:=
5949 Generic_Parent
(Specification
5950 (Unit_Declaration_Node
(P_Name
)));
5951 S
: Entity_Id
:= Current_Scope
;
5955 for J
in reverse 0 .. Scope_Stack
.Last
loop
5956 S
:= Scope_Stack
.Table
(J
).Entity
;
5958 exit when S
= Standard_Standard
;
5960 if Ekind_In
(S
, E_Function
,
5965 Generic_Parent
(Specification
5966 (Unit_Declaration_Node
(S
)));
5968 -- Check that P is a generic child of the generic
5969 -- parent of the prefix.
5972 and then Chars
(P
) = Chars
(Selector
)
5973 and then Scope
(P
) = Gen_Par
5984 -- If this is a selection from Ada, System or Interfaces, then
5985 -- we assume a missing with for the corresponding package.
5987 if Is_Known_Unit
(N
) then
5988 if not Error_Posted
(N
) then
5989 Error_Msg_Node_2
:= Selector
;
5990 Error_Msg_N
-- CODEFIX
5991 ("missing `WITH &.&;`", Prefix
(N
));
5994 -- If this is a selection from a dummy package, then suppress
5995 -- the error message, of course the entity is missing if the
5996 -- package is missing.
5998 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
6001 -- Here we have the case of an undefined component
6004 -- The prefix may hide a homonym in the context that
6005 -- declares the desired entity. This error can use a
6006 -- specialized message.
6008 if In_Open_Scopes
(P_Name
) then
6010 H
: constant Entity_Id
:= Homonym
(P_Name
);
6014 and then Is_Compilation_Unit
(H
)
6016 (Is_Immediately_Visible
(H
)
6017 or else Is_Visible_Lib_Unit
(H
))
6019 Id
:= First_Entity
(H
);
6020 while Present
(Id
) loop
6021 if Chars
(Id
) = Chars
(Selector
) then
6022 Error_Msg_Qual_Level
:= 99;
6023 Error_Msg_Name_1
:= Chars
(Selector
);
6025 ("% not declared in&", N
, P_Name
);
6027 ("\use fully qualified name starting with "
6028 & "Standard to make& visible", N
, H
);
6029 Error_Msg_Qual_Level
:= 0;
6037 -- If not found, standard error message
6039 Error_Msg_NE
("& not declared in&", N
, Selector
);
6045 Error_Msg_NE
("& not declared in&", N
, Selector
);
6048 -- Check for misspelling of some entity in prefix
6050 Id
:= First_Entity
(P_Name
);
6051 while Present
(Id
) loop
6052 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6053 and then not Is_Internal_Name
(Chars
(Id
))
6055 Error_Msg_NE
-- CODEFIX
6056 ("possible misspelling of&", Selector
, Id
);
6063 -- Specialize the message if this may be an instantiation
6064 -- of a child unit that was not mentioned in the context.
6066 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6067 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6068 and then Is_Compilation_Unit
6069 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6071 Error_Msg_Node_2
:= Selector
;
6072 Error_Msg_N
-- CODEFIX
6073 ("\missing `WITH &.&;`", Prefix
(N
));
6083 if Comes_From_Source
(N
)
6084 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6085 and then Ekind
(Id
) = E_Access_Subprogram_Type
6086 and then Present
(Equivalent_Type
(Id
))
6088 -- If we are not actually generating distribution code (i.e. the
6089 -- current PCS is the dummy non-distributed version), then the
6090 -- Equivalent_Type will be missing, and Id should be treated as
6091 -- a regular access-to-subprogram type.
6093 Id
:= Equivalent_Type
(Id
);
6094 Set_Chars
(Selector
, Chars
(Id
));
6097 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6099 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6100 if From_Limited_With
(Id
)
6101 or else Is_Type
(Id
)
6102 or else Ekind
(Id
) = E_Package
6107 ("limited withed package can only be used to access incomplete "
6112 if Is_Task_Type
(P_Name
)
6113 and then ((Ekind
(Id
) = E_Entry
6114 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6116 (Ekind
(Id
) = E_Entry_Family
6118 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6120 -- If both the task type and the entry are in scope, this may still
6121 -- be the expanded name of an entry formal.
6123 if In_Open_Scopes
(Id
)
6124 and then Nkind
(Parent
(N
)) = N_Selected_Component
6129 -- It is an entry call after all, either to the current task
6130 -- (which will deadlock) or to an enclosing task.
6132 Analyze_Selected_Component
(N
);
6137 Change_Selected_Component_To_Expanded_Name
(N
);
6139 -- Set appropriate type
6141 if Is_Type
(Id
) then
6144 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6147 -- Do style check and generate reference, but skip both steps if this
6148 -- entity has homonyms, since we may not have the right homonym set yet.
6149 -- The proper homonym will be set during the resolve phase.
6151 if Has_Homonym
(Id
) then
6155 Set_Entity_Or_Discriminal
(N
, Id
);
6159 Generate_Reference
(Id
, N
, 'm');
6161 Generate_Reference
(Id
, N
, 'r');
6163 Deferred_References
.Append
((Id
, N
));
6167 -- Check for violation of No_Wide_Characters
6169 Check_Wide_Character_Restriction
(Id
, N
);
6171 -- If the Ekind of the entity is Void, it means that all homonyms are
6172 -- hidden from all visibility (RM 8.3(5,14-20)).
6174 if Ekind
(Id
) = E_Void
then
6175 Premature_Usage
(N
);
6177 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6179 H
: Entity_Id
:= Homonym
(Id
);
6182 while Present
(H
) loop
6183 if Scope
(H
) = Scope
(Id
)
6184 and then (not Is_Hidden
(H
)
6185 or else Is_Immediately_Visible
(H
))
6187 Collect_Interps
(N
);
6194 -- If an extension of System is present, collect possible explicit
6195 -- overloadings declared in the extension.
6197 if Chars
(P_Name
) = Name_System
6198 and then Scope
(P_Name
) = Standard_Standard
6199 and then Present
(System_Extend_Unit
)
6200 and then Present_System_Aux
(N
)
6202 H
:= Current_Entity
(Id
);
6204 while Present
(H
) loop
6205 if Scope
(H
) = System_Aux_Id
then
6206 Add_One_Interp
(N
, H
, Etype
(H
));
6215 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6216 and then Scope
(Id
) /= Standard_Standard
6218 -- In addition to user-defined operators in the given scope, there
6219 -- may be an implicit instance of the predefined operator. The
6220 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6221 -- and added to the interpretations. Procedure Add_One_Interp will
6222 -- determine which hides which.
6224 if Has_Implicit_Operator
(N
) then
6229 -- If there is a single interpretation for N we can generate a
6230 -- reference to the unique entity found.
6232 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6233 Generate_Reference
(Id
, N
);
6236 Check_Restriction_No_Use_Of_Entity
(N
);
6237 end Find_Expanded_Name
;
6239 -------------------------
6240 -- Find_Renamed_Entity --
6241 -------------------------
6243 function Find_Renamed_Entity
6247 Is_Actual
: Boolean := False) return Entity_Id
6250 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6256 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6257 -- If the renamed entity is an implicit operator, check whether it is
6258 -- visible because its operand type is properly visible. This check
6259 -- applies to explicit renamed entities that appear in the source in a
6260 -- renaming declaration or a formal subprogram instance, but not to
6261 -- default generic actuals with a name.
6263 function Report_Overload
return Entity_Id
;
6264 -- List possible interpretations, and specialize message in the
6265 -- case of a generic actual.
6267 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6268 -- Determine whether a candidate subprogram is defined within the
6269 -- enclosing instance. If yes, it has precedence over outer candidates.
6271 --------------------------
6272 -- Is_Visible_Operation --
6273 --------------------------
6275 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6281 if Ekind
(Op
) /= E_Operator
6282 or else Scope
(Op
) /= Standard_Standard
6283 or else (In_Instance
6284 and then (not Is_Actual
6285 or else Present
(Enclosing_Instance
)))
6290 -- For a fixed point type operator, check the resulting type,
6291 -- because it may be a mixed mode integer * fixed operation.
6293 if Present
(Next_Formal
(First_Formal
(New_S
)))
6294 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6296 Typ
:= Etype
(New_S
);
6298 Typ
:= Etype
(First_Formal
(New_S
));
6301 Btyp
:= Base_Type
(Typ
);
6303 if Nkind
(Nam
) /= N_Expanded_Name
then
6304 return (In_Open_Scopes
(Scope
(Btyp
))
6305 or else Is_Potentially_Use_Visible
(Btyp
)
6306 or else In_Use
(Btyp
)
6307 or else In_Use
(Scope
(Btyp
)));
6310 Scop
:= Entity
(Prefix
(Nam
));
6312 if Ekind
(Scop
) = E_Package
6313 and then Present
(Renamed_Object
(Scop
))
6315 Scop
:= Renamed_Object
(Scop
);
6318 -- Operator is visible if prefix of expanded name denotes
6319 -- scope of type, or else type is defined in System_Aux
6320 -- and the prefix denotes System.
6322 return Scope
(Btyp
) = Scop
6323 or else (Scope
(Btyp
) = System_Aux_Id
6324 and then Scope
(Scope
(Btyp
)) = Scop
);
6327 end Is_Visible_Operation
;
6333 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6337 Sc
:= Scope
(Inner
);
6338 while Sc
/= Standard_Standard
loop
6349 ---------------------
6350 -- Report_Overload --
6351 ---------------------
6353 function Report_Overload
return Entity_Id
is
6356 Error_Msg_NE
-- CODEFIX
6357 ("ambiguous actual subprogram&, " &
6358 "possible interpretations:", N
, Nam
);
6360 Error_Msg_N
-- CODEFIX
6361 ("ambiguous subprogram, " &
6362 "possible interpretations:", N
);
6365 List_Interps
(Nam
, N
);
6367 end Report_Overload
;
6369 -- Start of processing for Find_Renamed_Entity
6373 Candidate_Renaming
:= Empty
;
6375 if Is_Overloaded
(Nam
) then
6376 Get_First_Interp
(Nam
, Ind
, It
);
6377 while Present
(It
.Nam
) loop
6378 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6379 and then Is_Visible_Operation
(It
.Nam
)
6381 if Old_S
/= Any_Id
then
6383 -- Note: The call to Disambiguate only happens if a
6384 -- previous interpretation was found, in which case I1
6385 -- has received a value.
6387 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6389 if It1
= No_Interp
then
6390 Inst
:= Enclosing_Instance
;
6392 if Present
(Inst
) then
6393 if Within
(It
.Nam
, Inst
) then
6394 if Within
(Old_S
, Inst
) then
6396 -- Choose the innermost subprogram, which would
6397 -- have hidden the outer one in the generic.
6399 if Scope_Depth
(It
.Nam
) <
6408 elsif Within
(Old_S
, Inst
) then
6412 return Report_Overload
;
6415 -- If not within an instance, ambiguity is real
6418 return Report_Overload
;
6432 Present
(First_Formal
(It
.Nam
))
6433 and then Present
(First_Formal
(New_S
))
6434 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6435 Base_Type
(Etype
(First_Formal
(New_S
))))
6437 Candidate_Renaming
:= It
.Nam
;
6440 Get_Next_Interp
(Ind
, It
);
6443 Set_Entity
(Nam
, Old_S
);
6445 if Old_S
/= Any_Id
then
6446 Set_Is_Overloaded
(Nam
, False);
6449 -- Non-overloaded case
6452 if Is_Actual
and then Present
(Enclosing_Instance
) then
6453 Old_S
:= Entity
(Nam
);
6455 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6456 Candidate_Renaming
:= New_S
;
6458 if Is_Visible_Operation
(Entity
(Nam
)) then
6459 Old_S
:= Entity
(Nam
);
6462 elsif Present
(First_Formal
(Entity
(Nam
)))
6463 and then Present
(First_Formal
(New_S
))
6464 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6465 Base_Type
(Etype
(First_Formal
(New_S
))))
6467 Candidate_Renaming
:= Entity
(Nam
);
6472 end Find_Renamed_Entity
;
6474 -----------------------------
6475 -- Find_Selected_Component --
6476 -----------------------------
6478 procedure Find_Selected_Component
(N
: Node_Id
) is
6479 P
: constant Node_Id
:= Prefix
(N
);
6482 -- Entity denoted by prefix
6489 function Available_Subtype
return Boolean;
6490 -- A small optimization: if the prefix is constrained and the component
6491 -- is an array type we may already have a usable subtype for it, so we
6492 -- can use it rather than generating a new one, because the bounds
6493 -- will be the values of the discriminants and not discriminant refs.
6494 -- This simplifies value tracing in GNATProve. For consistency, both
6495 -- the entity name and the subtype come from the constrained component.
6497 -- This is only used in GNATProve mode: when generating code it may be
6498 -- necessary to create an itype in the scope of use of the selected
6499 -- component, e.g. in the context of a expanded record equality.
6501 function Is_Reference_In_Subunit
return Boolean;
6502 -- In a subunit, the scope depth is not a proper measure of hiding,
6503 -- because the context of the proper body may itself hide entities in
6504 -- parent units. This rare case requires inspecting the tree directly
6505 -- because the proper body is inserted in the main unit and its context
6506 -- is simply added to that of the parent.
6508 -----------------------
6509 -- Available_Subtype --
6510 -----------------------
6512 function Available_Subtype
return Boolean is
6516 if GNATprove_Mode
then
6517 Comp
:= First_Entity
(Etype
(P
));
6518 while Present
(Comp
) loop
6519 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6520 Set_Etype
(N
, Etype
(Comp
));
6521 Set_Entity
(Selector_Name
(N
), Comp
);
6522 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6526 Next_Component
(Comp
);
6531 end Available_Subtype
;
6533 -----------------------------
6534 -- Is_Reference_In_Subunit --
6535 -----------------------------
6537 function Is_Reference_In_Subunit
return Boolean is
6539 Comp_Unit
: Node_Id
;
6543 while Present
(Comp_Unit
)
6544 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6546 Comp_Unit
:= Parent
(Comp_Unit
);
6549 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6553 -- Now check whether the package is in the context of the subunit
6555 Clause
:= First
(Context_Items
(Comp_Unit
));
6556 while Present
(Clause
) loop
6557 if Nkind
(Clause
) = N_With_Clause
6558 and then Entity
(Name
(Clause
)) = P_Name
6563 Clause
:= Next
(Clause
);
6567 end Is_Reference_In_Subunit
;
6569 -- Start of processing for Find_Selected_Component
6574 if Nkind
(P
) = N_Error
then
6578 -- Selector name cannot be a character literal or an operator symbol in
6579 -- SPARK, except for the operator symbol in a renaming.
6581 if Restriction_Check_Required
(SPARK_05
) then
6582 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6583 Check_SPARK_05_Restriction
6584 ("character literal cannot be prefixed", N
);
6585 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6586 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6588 Check_SPARK_05_Restriction
6589 ("operator symbol cannot be prefixed", N
);
6593 -- If the selector already has an entity, the node has been constructed
6594 -- in the course of expansion, and is known to be valid. Do not verify
6595 -- that it is defined for the type (it may be a private component used
6596 -- in the expansion of record equality).
6598 if Present
(Entity
(Selector_Name
(N
))) then
6599 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6601 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6602 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6606 Set_Etype
(Sel_Name
, Etype
(Selector
));
6608 if not Is_Entity_Name
(P
) then
6612 -- Build an actual subtype except for the first parameter
6613 -- of an init proc, where this actual subtype is by
6614 -- definition incorrect, since the object is uninitialized
6615 -- (and does not even have defined discriminants etc.)
6617 if Is_Entity_Name
(P
)
6618 and then Ekind
(Entity
(P
)) = E_Function
6620 Nam
:= New_Copy
(P
);
6622 if Is_Overloaded
(P
) then
6623 Save_Interps
(P
, Nam
);
6626 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6628 Analyze_Selected_Component
(N
);
6631 elsif Ekind
(Selector
) = E_Component
6632 and then (not Is_Entity_Name
(P
)
6633 or else Chars
(Entity
(P
)) /= Name_uInit
)
6635 -- Check if we already have an available subtype we can use
6637 if Ekind
(Etype
(P
)) = E_Record_Subtype
6638 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6639 and then Is_Array_Type
(Etype
(Selector
))
6640 and then not Is_Packed
(Etype
(Selector
))
6641 and then Available_Subtype
6645 -- Do not build the subtype when referencing components of
6646 -- dispatch table wrappers. Required to avoid generating
6647 -- elaboration code with HI runtimes.
6649 elsif RTU_Loaded
(Ada_Tags
)
6651 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6652 and then Scope
(Selector
) =
6653 RTE
(RE_Dispatch_Table_Wrapper
))
6655 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6656 and then Scope
(Selector
) =
6657 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6662 Build_Actual_Subtype_Of_Component
6663 (Etype
(Selector
), N
);
6670 if No
(C_Etype
) then
6671 C_Etype
:= Etype
(Selector
);
6673 Insert_Action
(N
, C_Etype
);
6674 C_Etype
:= Defining_Identifier
(C_Etype
);
6677 Set_Etype
(N
, C_Etype
);
6680 -- If this is the name of an entry or protected operation, and
6681 -- the prefix is an access type, insert an explicit dereference,
6682 -- so that entry calls are treated uniformly.
6684 if Is_Access_Type
(Etype
(P
))
6685 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6688 New_P
: constant Node_Id
:=
6689 Make_Explicit_Dereference
(Sloc
(P
),
6690 Prefix
=> Relocate_Node
(P
));
6693 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6697 -- If the selected component appears within a default expression
6698 -- and it has an actual subtype, the pre-analysis has not yet
6699 -- completed its analysis, because Insert_Actions is disabled in
6700 -- that context. Within the init proc of the enclosing type we
6701 -- must complete this analysis, if an actual subtype was created.
6703 elsif Inside_Init_Proc
then
6705 Typ
: constant Entity_Id
:= Etype
(N
);
6706 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6708 if Nkind
(Decl
) = N_Subtype_Declaration
6709 and then not Analyzed
(Decl
)
6710 and then Is_List_Member
(Decl
)
6711 and then No
(Parent
(Decl
))
6714 Insert_Action
(N
, Decl
);
6721 elsif Is_Entity_Name
(P
) then
6722 P_Name
:= Entity
(P
);
6724 -- The prefix may denote an enclosing type which is the completion
6725 -- of an incomplete type declaration.
6727 if Is_Type
(P_Name
) then
6728 Set_Entity
(P
, Get_Full_View
(P_Name
));
6729 Set_Etype
(P
, Entity
(P
));
6730 P_Name
:= Entity
(P
);
6733 P_Type
:= Base_Type
(Etype
(P
));
6735 if Debug_Flag_E
then
6736 Write_Str
("Found prefix type to be ");
6737 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6740 -- The designated type may be a limited view with no components.
6741 -- Check whether the non-limited view is available, because in some
6742 -- cases this will not be set when installing the context. Rewrite
6743 -- the node by introducing an explicit dereference at once, and
6744 -- setting the type of the rewritten prefix to the non-limited view
6745 -- of the original designated type.
6747 if Is_Access_Type
(P_Type
) then
6749 Desig_Typ
: constant Entity_Id
:=
6750 Directly_Designated_Type
(P_Type
);
6753 if Is_Incomplete_Type
(Desig_Typ
)
6754 and then From_Limited_With
(Desig_Typ
)
6755 and then Present
(Non_Limited_View
(Desig_Typ
))
6758 Make_Explicit_Dereference
(Sloc
(P
),
6759 Prefix
=> Relocate_Node
(P
)));
6761 Set_Etype
(P
, Get_Full_View
(Non_Limited_View
(Desig_Typ
)));
6762 P_Type
:= Etype
(P
);
6767 -- First check for components of a record object (not the
6768 -- result of a call, which is handled below).
6770 if Is_Appropriate_For_Record
(P_Type
)
6771 and then not Is_Overloadable
(P_Name
)
6772 and then not Is_Type
(P_Name
)
6774 -- Selected component of record. Type checking will validate
6775 -- name of selector.
6777 -- ??? Could we rewrite an implicit dereference into an explicit
6780 Analyze_Selected_Component
(N
);
6782 -- Reference to type name in predicate/invariant expression
6784 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6785 and then not In_Open_Scopes
(P_Name
)
6786 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6787 or else not In_Open_Scopes
(Etype
(P_Name
)))
6789 -- Call to protected operation or entry. Type checking is
6790 -- needed on the prefix.
6792 Analyze_Selected_Component
(N
);
6794 elsif (In_Open_Scopes
(P_Name
)
6795 and then Ekind
(P_Name
) /= E_Void
6796 and then not Is_Overloadable
(P_Name
))
6797 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6798 and then In_Open_Scopes
(Etype
(P_Name
)))
6800 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6801 -- enclosing construct that is not a subprogram or accept.
6803 -- A special case: a protected body may call an operation
6804 -- on an external object of the same type, in which case it
6805 -- is not an expanded name. If the prefix is the type itself,
6806 -- or the context is a single synchronized object it can only
6807 -- be interpreted as an expanded name.
6809 if Is_Concurrent_Type
(Etype
(P_Name
)) then
6811 or else Present
(Anonymous_Object
(Etype
(P_Name
)))
6813 Find_Expanded_Name
(N
);
6816 Analyze_Selected_Component
(N
);
6821 Find_Expanded_Name
(N
);
6824 elsif Ekind
(P_Name
) = E_Package
then
6825 Find_Expanded_Name
(N
);
6827 elsif Is_Overloadable
(P_Name
) then
6829 -- The subprogram may be a renaming (of an enclosing scope) as
6830 -- in the case of the name of the generic within an instantiation.
6832 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6833 and then Present
(Alias
(P_Name
))
6834 and then Is_Generic_Instance
(Alias
(P_Name
))
6836 P_Name
:= Alias
(P_Name
);
6839 if Is_Overloaded
(P
) then
6841 -- The prefix must resolve to a unique enclosing construct
6844 Found
: Boolean := False;
6849 Get_First_Interp
(P
, Ind
, It
);
6850 while Present
(It
.Nam
) loop
6851 if In_Open_Scopes
(It
.Nam
) then
6854 "prefix must be unique enclosing scope", N
);
6855 Set_Entity
(N
, Any_Id
);
6856 Set_Etype
(N
, Any_Type
);
6865 Get_Next_Interp
(Ind
, It
);
6870 if In_Open_Scopes
(P_Name
) then
6871 Set_Entity
(P
, P_Name
);
6872 Set_Is_Overloaded
(P
, False);
6873 Find_Expanded_Name
(N
);
6876 -- If no interpretation as an expanded name is possible, it
6877 -- must be a selected component of a record returned by a
6878 -- function call. Reformat prefix as a function call, the rest
6879 -- is done by type resolution.
6881 -- Error if the prefix is procedure or entry, as is P.X
6883 if Ekind
(P_Name
) /= E_Function
6885 (not Is_Overloaded
(P
)
6886 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6888 -- Prefix may mention a package that is hidden by a local
6889 -- declaration: let the user know. Scan the full homonym
6890 -- chain, the candidate package may be anywhere on it.
6892 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6893 P_Name
:= Current_Entity
(P_Name
);
6895 while Present
(P_Name
) loop
6896 exit when Ekind
(P_Name
) = E_Package
;
6897 P_Name
:= Homonym
(P_Name
);
6900 if Present
(P_Name
) then
6901 if not Is_Reference_In_Subunit
then
6902 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6904 ("package& is hidden by declaration#", N
, P_Name
);
6907 Set_Entity
(Prefix
(N
), P_Name
);
6908 Find_Expanded_Name
(N
);
6912 P_Name
:= Entity
(Prefix
(N
));
6917 ("invalid prefix in selected component&", N
, P_Name
);
6918 Change_Selected_Component_To_Expanded_Name
(N
);
6919 Set_Entity
(N
, Any_Id
);
6920 Set_Etype
(N
, Any_Type
);
6922 -- Here we have a function call, so do the reformatting
6925 Nam
:= New_Copy
(P
);
6926 Save_Interps
(P
, Nam
);
6928 -- We use Replace here because this is one of those cases
6929 -- where the parser has missclassified the node, and we
6930 -- fix things up and then do the semantic analysis on the
6931 -- fixed up node. Normally we do this using one of the
6932 -- Sinfo.CN routines, but this is too tricky for that.
6934 -- Note that using Rewrite would be wrong, because we
6935 -- would have a tree where the original node is unanalyzed,
6936 -- and this violates the required interface for ASIS.
6939 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6941 -- Now analyze the reformatted node
6944 Analyze_Selected_Component
(N
);
6948 -- Remaining cases generate various error messages
6951 -- Format node as expanded name, to avoid cascaded errors
6953 -- If the limited_with transformation was applied earlier,
6954 -- restore source for proper error reporting.
6956 if not Comes_From_Source
(P
)
6957 and then Nkind
(P
) = N_Explicit_Dereference
6959 Rewrite
(P
, Prefix
(P
));
6960 P_Type
:= Etype
(P
);
6963 Change_Selected_Component_To_Expanded_Name
(N
);
6964 Set_Entity
(N
, Any_Id
);
6965 Set_Etype
(N
, Any_Type
);
6967 -- Issue error message, but avoid this if error issued already.
6968 -- Use identifier of prefix if one is available.
6970 if P_Name
= Any_Id
then
6973 -- It is not an error if the prefix is the current instance of
6974 -- type name, e.g. the expression of a type aspect, when it is
6975 -- analyzed for ASIS use.
6977 elsif Is_Entity_Name
(P
) and then Is_Current_Instance
(P
) then
6980 elsif Ekind
(P_Name
) = E_Void
then
6981 Premature_Usage
(P
);
6983 elsif Nkind
(P
) /= N_Attribute_Reference
then
6985 -- This may have been meant as a prefixed call to a primitive
6986 -- of an untagged type. If it is a function call check type of
6987 -- its first formal and add explanation.
6990 F
: constant Entity_Id
:=
6991 Current_Entity
(Selector_Name
(N
));
6994 and then Is_Overloadable
(F
)
6995 and then Present
(First_Entity
(F
))
6996 and then not Is_Tagged_Type
(Etype
(First_Entity
(F
)))
6999 ("prefixed call is only allowed for objects of a "
7000 & "tagged type", N
);
7004 Error_Msg_N
("invalid prefix in selected component&", P
);
7006 if Is_Access_Type
(P_Type
)
7007 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
7010 ("\dereference must not be of an incomplete type "
7011 & "(RM 3.10.1)", P
);
7015 Error_Msg_N
("invalid prefix in selected component", P
);
7019 -- Selector name is restricted in SPARK
7021 if Nkind
(N
) = N_Expanded_Name
7022 and then Restriction_Check_Required
(SPARK_05
)
7024 if Is_Subprogram
(P_Name
) then
7025 Check_SPARK_05_Restriction
7026 ("prefix of expanded name cannot be a subprogram", P
);
7027 elsif Ekind
(P_Name
) = E_Loop
then
7028 Check_SPARK_05_Restriction
7029 ("prefix of expanded name cannot be a loop statement", P
);
7034 -- If prefix is not the name of an entity, it must be an expression,
7035 -- whose type is appropriate for a record. This is determined by
7038 Analyze_Selected_Component
(N
);
7041 Analyze_Dimension
(N
);
7042 end Find_Selected_Component
;
7048 procedure Find_Type
(N
: Node_Id
) is
7058 elsif Nkind
(N
) = N_Attribute_Reference
then
7060 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7061 -- need to enforce that at this point, since the declaration of the
7062 -- tagged type in the prefix would have been flagged already.
7064 if Attribute_Name
(N
) = Name_Class
then
7065 Check_Restriction
(No_Dispatch
, N
);
7066 Find_Type
(Prefix
(N
));
7068 -- Propagate error from bad prefix
7070 if Etype
(Prefix
(N
)) = Any_Type
then
7071 Set_Entity
(N
, Any_Type
);
7072 Set_Etype
(N
, Any_Type
);
7076 T
:= Base_Type
(Entity
(Prefix
(N
)));
7078 -- Case where type is not known to be tagged. Its appearance in
7079 -- the prefix of the 'Class attribute indicates that the full view
7082 if not Is_Tagged_Type
(T
) then
7083 if Ekind
(T
) = E_Incomplete_Type
then
7085 -- It is legal to denote the class type of an incomplete
7086 -- type. The full type will have to be tagged, of course.
7087 -- In Ada 2005 this usage is declared obsolescent, so we
7088 -- warn accordingly. This usage is only legal if the type
7089 -- is completed in the current scope, and not for a limited
7092 if Ada_Version
>= Ada_2005
then
7094 -- Test whether the Available_View of a limited type view
7095 -- is tagged, since the limited view may not be marked as
7096 -- tagged if the type itself has an untagged incomplete
7097 -- type view in its package.
7099 if From_Limited_With
(T
)
7100 and then not Is_Tagged_Type
(Available_View
(T
))
7103 ("prefix of Class attribute must be tagged", N
);
7104 Set_Etype
(N
, Any_Type
);
7105 Set_Entity
(N
, Any_Type
);
7108 -- ??? This test is temporarily disabled (always
7109 -- False) because it causes an unwanted warning on
7110 -- GNAT sources (built with -gnatg, which includes
7111 -- Warn_On_Obsolescent_ Feature). Once this issue
7112 -- is cleared in the sources, it can be enabled.
7114 elsif Warn_On_Obsolescent_Feature
and then False then
7116 ("applying 'Class to an untagged incomplete type"
7117 & " is an obsolescent feature (RM J.11)?r?", N
);
7121 Set_Is_Tagged_Type
(T
);
7122 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7123 Make_Class_Wide_Type
(T
);
7124 Set_Entity
(N
, Class_Wide_Type
(T
));
7125 Set_Etype
(N
, Class_Wide_Type
(T
));
7127 elsif Ekind
(T
) = E_Private_Type
7128 and then not Is_Generic_Type
(T
)
7129 and then In_Private_Part
(Scope
(T
))
7131 -- The Class attribute can be applied to an untagged private
7132 -- type fulfilled by a tagged type prior to the full type
7133 -- declaration (but only within the parent package's private
7134 -- part). Create the class-wide type now and check that the
7135 -- full type is tagged later during its analysis. Note that
7136 -- we do not mark the private type as tagged, unlike the
7137 -- case of incomplete types, because the type must still
7138 -- appear untagged to outside units.
7140 if No
(Class_Wide_Type
(T
)) then
7141 Make_Class_Wide_Type
(T
);
7144 Set_Entity
(N
, Class_Wide_Type
(T
));
7145 Set_Etype
(N
, Class_Wide_Type
(T
));
7148 -- Should we introduce a type Any_Tagged and use Wrong_Type
7149 -- here, it would be a bit more consistent???
7152 ("tagged type required, found}",
7153 Prefix
(N
), First_Subtype
(T
));
7154 Set_Entity
(N
, Any_Type
);
7158 -- Case of tagged type
7161 if Is_Concurrent_Type
(T
) then
7162 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7164 -- Previous error. Use current type, which at least
7165 -- provides some operations.
7167 C
:= Entity
(Prefix
(N
));
7170 C
:= Class_Wide_Type
7171 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7175 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7178 Set_Entity_With_Checks
(N
, C
);
7179 Generate_Reference
(C
, N
);
7183 -- Base attribute, not allowed in Ada 83
7185 elsif Attribute_Name
(N
) = Name_Base
then
7186 Error_Msg_Name_1
:= Name_Base
;
7187 Check_SPARK_05_Restriction
7188 ("attribute% is only allowed as prefix of another attribute", N
);
7190 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7192 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7195 Find_Type
(Prefix
(N
));
7196 Typ
:= Entity
(Prefix
(N
));
7198 if Ada_Version
>= Ada_95
7199 and then not Is_Scalar_Type
(Typ
)
7200 and then not Is_Generic_Type
(Typ
)
7203 ("prefix of Base attribute must be scalar type",
7206 elsif Warn_On_Redundant_Constructs
7207 and then Base_Type
(Typ
) = Typ
7209 Error_Msg_NE
-- CODEFIX
7210 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7213 T
:= Base_Type
(Typ
);
7215 -- Rewrite attribute reference with type itself (see similar
7216 -- processing in Analyze_Attribute, case Base). Preserve prefix
7217 -- if present, for other legality checks.
7219 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7221 Make_Expanded_Name
(Sloc
(N
),
7223 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7224 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7227 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7234 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7236 -- This is handled in Analyze_Attribute
7240 -- All other attributes are invalid in a subtype mark
7243 Error_Msg_N
("invalid attribute in subtype mark", N
);
7249 if Is_Entity_Name
(N
) then
7250 T_Name
:= Entity
(N
);
7252 Error_Msg_N
("subtype mark required in this context", N
);
7253 Set_Etype
(N
, Any_Type
);
7257 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7259 -- Undefined id. Make it into a valid type
7261 Set_Entity
(N
, Any_Type
);
7263 elsif not Is_Type
(T_Name
)
7264 and then T_Name
/= Standard_Void_Type
7266 Error_Msg_Sloc
:= Sloc
(T_Name
);
7267 Error_Msg_N
("subtype mark required in this context", N
);
7268 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7269 Set_Entity
(N
, Any_Type
);
7272 -- If the type is an incomplete type created to handle
7273 -- anonymous access components of a record type, then the
7274 -- incomplete type is the visible entity and subsequent
7275 -- references will point to it. Mark the original full
7276 -- type as referenced, to prevent spurious warnings.
7278 if Is_Incomplete_Type
(T_Name
)
7279 and then Present
(Full_View
(T_Name
))
7280 and then not Comes_From_Source
(T_Name
)
7282 Set_Referenced
(Full_View
(T_Name
));
7285 T_Name
:= Get_Full_View
(T_Name
);
7287 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7288 -- limited-with clauses
7290 if From_Limited_With
(T_Name
)
7291 and then Ekind
(T_Name
) in Incomplete_Kind
7292 and then Present
(Non_Limited_View
(T_Name
))
7293 and then Is_Interface
(Non_Limited_View
(T_Name
))
7295 T_Name
:= Non_Limited_View
(T_Name
);
7298 if In_Open_Scopes
(T_Name
) then
7299 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7301 -- In Ada 2005, a task name can be used in an access
7302 -- definition within its own body. It cannot be used
7303 -- in the discriminant part of the task declaration,
7304 -- nor anywhere else in the declaration because entries
7305 -- cannot have access parameters.
7307 if Ada_Version
>= Ada_2005
7308 and then Nkind
(Parent
(N
)) = N_Access_Definition
7310 Set_Entity
(N
, T_Name
);
7311 Set_Etype
(N
, T_Name
);
7313 if Has_Completion
(T_Name
) then
7318 ("task type cannot be used as type mark " &
7319 "within its own declaration", N
);
7324 ("task type cannot be used as type mark " &
7325 "within its own spec or body", N
);
7328 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7330 -- In Ada 2005, a protected name can be used in an access
7331 -- definition within its own body.
7333 if Ada_Version
>= Ada_2005
7334 and then Nkind
(Parent
(N
)) = N_Access_Definition
7336 Set_Entity
(N
, T_Name
);
7337 Set_Etype
(N
, T_Name
);
7342 ("protected type cannot be used as type mark " &
7343 "within its own spec or body", N
);
7347 Error_Msg_N
("type declaration cannot refer to itself", N
);
7350 Set_Etype
(N
, Any_Type
);
7351 Set_Entity
(N
, Any_Type
);
7352 Set_Error_Posted
(T_Name
);
7356 Set_Entity
(N
, T_Name
);
7357 Set_Etype
(N
, T_Name
);
7361 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7362 if Is_Fixed_Point_Type
(Etype
(N
)) then
7363 Check_Restriction
(No_Fixed_Point
, N
);
7364 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7365 Check_Restriction
(No_Floating_Point
, N
);
7368 -- A Ghost type must appear in a specific context
7370 if Is_Ghost_Entity
(Etype
(N
)) then
7371 Check_Ghost_Context
(Etype
(N
), N
);
7376 ------------------------------------
7377 -- Has_Implicit_Character_Literal --
7378 ------------------------------------
7380 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7382 Found
: Boolean := False;
7383 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7384 Priv_Id
: Entity_Id
:= Empty
;
7387 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7388 Priv_Id
:= First_Private_Entity
(P
);
7391 if P
= Standard_Standard
then
7392 Change_Selected_Component_To_Expanded_Name
(N
);
7393 Rewrite
(N
, Selector_Name
(N
));
7395 Set_Etype
(Original_Node
(N
), Standard_Character
);
7399 Id
:= First_Entity
(P
);
7400 while Present
(Id
) and then Id
/= Priv_Id
loop
7401 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7403 -- We replace the node with the literal itself, resolve as a
7404 -- character, and set the type correctly.
7407 Change_Selected_Component_To_Expanded_Name
(N
);
7408 Rewrite
(N
, Selector_Name
(N
));
7411 Set_Etype
(Original_Node
(N
), Id
);
7415 -- More than one type derived from Character in given scope.
7416 -- Collect all possible interpretations.
7418 Add_One_Interp
(N
, Id
, Id
);
7426 end Has_Implicit_Character_Literal
;
7428 ----------------------
7429 -- Has_Private_With --
7430 ----------------------
7432 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7433 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7437 Item
:= First
(Context_Items
(Comp_Unit
));
7438 while Present
(Item
) loop
7439 if Nkind
(Item
) = N_With_Clause
7440 and then Private_Present
(Item
)
7441 and then Entity
(Name
(Item
)) = E
7450 end Has_Private_With
;
7452 ---------------------------
7453 -- Has_Implicit_Operator --
7454 ---------------------------
7456 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7457 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7458 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7460 Priv_Id
: Entity_Id
:= Empty
;
7462 procedure Add_Implicit_Operator
7464 Op_Type
: Entity_Id
:= Empty
);
7465 -- Add implicit interpretation to node N, using the type for which a
7466 -- predefined operator exists. If the operator yields a boolean type,
7467 -- the Operand_Type is implicitly referenced by the operator, and a
7468 -- reference to it must be generated.
7470 ---------------------------
7471 -- Add_Implicit_Operator --
7472 ---------------------------
7474 procedure Add_Implicit_Operator
7476 Op_Type
: Entity_Id
:= Empty
)
7478 Predef_Op
: Entity_Id
;
7481 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7482 while Present
(Predef_Op
)
7483 and then Scope
(Predef_Op
) /= Standard_Standard
7485 Predef_Op
:= Homonym
(Predef_Op
);
7488 if Nkind
(N
) = N_Selected_Component
then
7489 Change_Selected_Component_To_Expanded_Name
(N
);
7492 -- If the context is an unanalyzed function call, determine whether
7493 -- a binary or unary interpretation is required.
7495 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7497 Is_Binary_Call
: constant Boolean :=
7499 (Next
(First
(Expressions
(Parent
(N
)))));
7500 Is_Binary_Op
: constant Boolean :=
7502 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7503 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7506 if Is_Binary_Call
then
7507 if Is_Binary_Op
then
7508 Add_One_Interp
(N
, Predef_Op
, T
);
7510 Add_One_Interp
(N
, Predef_Op2
, T
);
7514 if not Is_Binary_Op
then
7515 Add_One_Interp
(N
, Predef_Op
, T
);
7517 Add_One_Interp
(N
, Predef_Op2
, T
);
7523 Add_One_Interp
(N
, Predef_Op
, T
);
7525 -- For operators with unary and binary interpretations, if
7526 -- context is not a call, add both
7528 if Present
(Homonym
(Predef_Op
)) then
7529 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7533 -- The node is a reference to a predefined operator, and
7534 -- an implicit reference to the type of its operands.
7536 if Present
(Op_Type
) then
7537 Generate_Operator_Reference
(N
, Op_Type
);
7539 Generate_Operator_Reference
(N
, T
);
7541 end Add_Implicit_Operator
;
7543 -- Start of processing for Has_Implicit_Operator
7546 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7547 Priv_Id
:= First_Private_Entity
(P
);
7550 Id
:= First_Entity
(P
);
7554 -- Boolean operators: an implicit declaration exists if the scope
7555 -- contains a declaration for a derived Boolean type, or for an
7556 -- array of Boolean type.
7558 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7559 while Id
/= Priv_Id
loop
7560 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7561 Add_Implicit_Operator
(Id
);
7568 -- Equality: look for any non-limited type (result is Boolean)
7570 when Name_Op_Eq | Name_Op_Ne
=>
7571 while Id
/= Priv_Id
loop
7573 and then not Is_Limited_Type
(Id
)
7574 and then Is_Base_Type
(Id
)
7576 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7583 -- Comparison operators: scalar type, or array of scalar
7585 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7586 while Id
/= Priv_Id
loop
7587 if (Is_Scalar_Type
(Id
)
7588 or else (Is_Array_Type
(Id
)
7589 and then Is_Scalar_Type
(Component_Type
(Id
))))
7590 and then Is_Base_Type
(Id
)
7592 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7599 -- Arithmetic operators: any numeric type
7609 while Id
/= Priv_Id
loop
7610 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7611 Add_Implicit_Operator
(Id
);
7618 -- Concatenation: any one-dimensional array type
7620 when Name_Op_Concat
=>
7621 while Id
/= Priv_Id
loop
7622 if Is_Array_Type
(Id
)
7623 and then Number_Dimensions
(Id
) = 1
7624 and then Is_Base_Type
(Id
)
7626 Add_Implicit_Operator
(Id
);
7633 -- What is the others condition here? Should we be using a
7634 -- subtype of Name_Id that would restrict to operators ???
7636 when others => null;
7639 -- If we fall through, then we do not have an implicit operator
7643 end Has_Implicit_Operator
;
7645 -----------------------------------
7646 -- Has_Loop_In_Inner_Open_Scopes --
7647 -----------------------------------
7649 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7651 -- Several scope stacks are maintained by Scope_Stack. The base of the
7652 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7653 -- flag in the scope stack entry. Note that the scope stacks used to
7654 -- simply be delimited implicitly by the presence of Standard_Standard
7655 -- at their base, but there now are cases where this is not sufficient
7656 -- because Standard_Standard actually may appear in the middle of the
7657 -- active set of scopes.
7659 for J
in reverse 0 .. Scope_Stack
.Last
loop
7661 -- S was reached without seing a loop scope first
7663 if Scope_Stack
.Table
(J
).Entity
= S
then
7666 -- S was not yet reached, so it contains at least one inner loop
7668 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7672 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7673 -- cases where Standard_Standard appears in the middle of the active
7674 -- set of scopes. This affects the declaration and overriding of
7675 -- private inherited operations in instantiations of generic child
7678 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7681 raise Program_Error
; -- unreachable
7682 end Has_Loop_In_Inner_Open_Scopes
;
7684 --------------------
7685 -- In_Open_Scopes --
7686 --------------------
7688 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7690 -- Several scope stacks are maintained by Scope_Stack. The base of the
7691 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7692 -- flag in the scope stack entry. Note that the scope stacks used to
7693 -- simply be delimited implicitly by the presence of Standard_Standard
7694 -- at their base, but there now are cases where this is not sufficient
7695 -- because Standard_Standard actually may appear in the middle of the
7696 -- active set of scopes.
7698 for J
in reverse 0 .. Scope_Stack
.Last
loop
7699 if Scope_Stack
.Table
(J
).Entity
= S
then
7703 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7704 -- cases where Standard_Standard appears in the middle of the active
7705 -- set of scopes. This affects the declaration and overriding of
7706 -- private inherited operations in instantiations of generic child
7709 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7715 -----------------------------
7716 -- Inherit_Renamed_Profile --
7717 -----------------------------
7719 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7726 if Ekind
(Old_S
) = E_Operator
then
7727 New_F
:= First_Formal
(New_S
);
7729 while Present
(New_F
) loop
7730 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7731 Next_Formal
(New_F
);
7734 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7737 New_F
:= First_Formal
(New_S
);
7738 Old_F
:= First_Formal
(Old_S
);
7740 while Present
(New_F
) loop
7741 New_T
:= Etype
(New_F
);
7742 Old_T
:= Etype
(Old_F
);
7744 -- If the new type is a renaming of the old one, as is the
7745 -- case for actuals in instances, retain its name, to simplify
7746 -- later disambiguation.
7748 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7749 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7750 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7754 Set_Etype
(New_F
, Old_T
);
7757 Next_Formal
(New_F
);
7758 Next_Formal
(Old_F
);
7761 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7762 Set_Etype
(New_S
, Etype
(Old_S
));
7765 end Inherit_Renamed_Profile
;
7771 procedure Initialize
is
7776 -------------------------
7777 -- Install_Use_Clauses --
7778 -------------------------
7780 procedure Install_Use_Clauses
7782 Force_Installation
: Boolean := False)
7790 while Present
(U
) loop
7792 -- Case of USE package
7794 if Nkind
(U
) = N_Use_Package_Clause
then
7795 P
:= First
(Names
(U
));
7796 while Present
(P
) loop
7799 if Ekind
(Id
) = E_Package
then
7801 Note_Redundant_Use
(P
);
7803 elsif Present
(Renamed_Object
(Id
))
7804 and then In_Use
(Renamed_Object
(Id
))
7806 Note_Redundant_Use
(P
);
7808 elsif Force_Installation
or else Applicable_Use
(P
) then
7809 Use_One_Package
(Id
, U
);
7820 P
:= First
(Subtype_Marks
(U
));
7821 while Present
(P
) loop
7822 if not Is_Entity_Name
(P
)
7823 or else No
(Entity
(P
))
7827 elsif Entity
(P
) /= Any_Type
then
7835 Next_Use_Clause
(U
);
7837 end Install_Use_Clauses
;
7839 -------------------------------------
7840 -- Is_Appropriate_For_Entry_Prefix --
7841 -------------------------------------
7843 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7844 P_Type
: Entity_Id
:= T
;
7847 if Is_Access_Type
(P_Type
) then
7848 P_Type
:= Designated_Type
(P_Type
);
7851 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7852 end Is_Appropriate_For_Entry_Prefix
;
7854 -------------------------------
7855 -- Is_Appropriate_For_Record --
7856 -------------------------------
7858 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7860 function Has_Components
(T1
: Entity_Id
) return Boolean;
7861 -- Determine if given type has components (i.e. is either a record
7862 -- type or a type that has discriminants).
7864 --------------------
7865 -- Has_Components --
7866 --------------------
7868 function Has_Components
(T1
: Entity_Id
) return Boolean is
7870 return Is_Record_Type
(T1
)
7871 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7872 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7873 or else (Is_Incomplete_Type
(T1
)
7874 and then From_Limited_With
(T1
)
7875 and then Present
(Non_Limited_View
(T1
))
7876 and then Is_Record_Type
7877 (Get_Full_View
(Non_Limited_View
(T1
))));
7880 -- Start of processing for Is_Appropriate_For_Record
7885 and then (Has_Components
(T
)
7886 or else (Is_Access_Type
(T
)
7887 and then Has_Components
(Designated_Type
(T
))));
7888 end Is_Appropriate_For_Record
;
7890 ------------------------
7891 -- Note_Redundant_Use --
7892 ------------------------
7894 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7895 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7896 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7897 Decl
: constant Node_Id
:= Parent
(Clause
);
7899 Prev_Use
: Node_Id
:= Empty
;
7900 Redundant
: Node_Id
:= Empty
;
7901 -- The Use_Clause which is actually redundant. In the simplest case it
7902 -- is Pack itself, but when we compile a body we install its context
7903 -- before that of its spec, in which case it is the use_clause in the
7904 -- spec that will appear to be redundant, and we want the warning to be
7905 -- placed on the body. Similar complications appear when the redundancy
7906 -- is between a child unit and one of its ancestors.
7909 Set_Redundant_Use
(Clause
, True);
7911 if not Comes_From_Source
(Clause
)
7913 or else not Warn_On_Redundant_Constructs
7918 if not Is_Compilation_Unit
(Current_Scope
) then
7920 -- If the use_clause is in an inner scope, it is made redundant by
7921 -- some clause in the current context, with one exception: If we're
7922 -- compiling a nested package body, and the use_clause comes from the
7923 -- corresponding spec, the clause is not necessarily fully redundant,
7924 -- so we should not warn. If a warning was warranted, it would have
7925 -- been given when the spec was processed.
7927 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7929 Package_Spec_Entity
: constant Entity_Id
:=
7930 Defining_Unit_Name
(Parent
(Decl
));
7932 if In_Package_Body
(Package_Spec_Entity
) then
7938 Redundant
:= Clause
;
7939 Prev_Use
:= Cur_Use
;
7941 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7943 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7944 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7948 if Cur_Unit
= New_Unit
then
7950 -- Redundant clause in same body
7952 Redundant
:= Clause
;
7953 Prev_Use
:= Cur_Use
;
7955 elsif Cur_Unit
= Current_Sem_Unit
then
7957 -- If the new clause is not in the current unit it has been
7958 -- analyzed first, and it makes the other one redundant.
7959 -- However, if the new clause appears in a subunit, Cur_Unit
7960 -- is still the parent, and in that case the redundant one
7961 -- is the one appearing in the subunit.
7963 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7964 Redundant
:= Clause
;
7965 Prev_Use
:= Cur_Use
;
7967 -- Most common case: redundant clause in body,
7968 -- original clause in spec. Current scope is spec entity.
7973 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7975 Redundant
:= Cur_Use
;
7979 -- The new clause may appear in an unrelated unit, when
7980 -- the parents of a generic are being installed prior to
7981 -- instantiation. In this case there must be no warning.
7982 -- We detect this case by checking whether the current top
7983 -- of the stack is related to the current compilation.
7985 Scop
:= Current_Scope
;
7986 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7987 if Is_Compilation_Unit
(Scop
)
7988 and then not Is_Child_Unit
(Scop
)
7992 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7996 Scop
:= Scope
(Scop
);
7999 Redundant
:= Cur_Use
;
8003 elsif New_Unit
= Current_Sem_Unit
then
8004 Redundant
:= Clause
;
8005 Prev_Use
:= Cur_Use
;
8008 -- Neither is the current unit, so they appear in parent or
8009 -- sibling units. Warning will be emitted elsewhere.
8015 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
8016 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
8018 -- Use_clause is in child unit of current unit, and the child unit
8019 -- appears in the context of the body of the parent, so it has been
8020 -- installed first, even though it is the redundant one. Depending on
8021 -- their placement in the context, the visible or the private parts
8022 -- of the two units, either might appear as redundant, but the
8023 -- message has to be on the current unit.
8025 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
8026 Redundant
:= Cur_Use
;
8029 Redundant
:= Clause
;
8030 Prev_Use
:= Cur_Use
;
8033 -- If the new use clause appears in the private part of a parent unit
8034 -- it may appear to be redundant w.r.t. a use clause in a child unit,
8035 -- but the previous use clause was needed in the visible part of the
8036 -- child, and no warning should be emitted.
8038 if Nkind
(Parent
(Decl
)) = N_Package_Specification
8040 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
8043 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
8044 Spec
: constant Node_Id
:=
8045 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
8048 if Is_Compilation_Unit
(Par
)
8049 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
8050 and then Parent
(Cur_Use
) = Spec
8052 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
8059 -- Finally, if the current use clause is in the context then
8060 -- the clause is redundant when it is nested within the unit.
8062 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
8063 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
8064 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
8066 Redundant
:= Clause
;
8067 Prev_Use
:= Cur_Use
;
8073 if Present
(Redundant
) then
8074 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
8075 Error_Msg_NE
-- CODEFIX
8076 ("& is already use-visible through previous use clause #??",
8077 Redundant
, Pack_Name
);
8079 end Note_Redundant_Use
;
8085 procedure Pop_Scope
is
8086 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8087 S
: constant Entity_Id
:= SST
.Entity
;
8090 if Debug_Flag_E
then
8094 -- Set Default_Storage_Pool field of the library unit if necessary
8096 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8098 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8101 Aux
: constant Node_Id
:=
8102 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8104 if No
(Default_Storage_Pool
(Aux
)) then
8105 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8110 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8111 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8112 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8113 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8114 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8115 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8116 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8117 Default_SSO
:= SST
.Save_Default_SSO
;
8118 Uneval_Old
:= SST
.Save_Uneval_Old
;
8120 if Debug_Flag_W
then
8121 Write_Str
("<-- exiting scope: ");
8122 Write_Name
(Chars
(Current_Scope
));
8123 Write_Str
(", Depth=");
8124 Write_Int
(Int
(Scope_Stack
.Last
));
8128 End_Use_Clauses
(SST
.First_Use_Clause
);
8130 -- If the actions to be wrapped are still there they will get lost
8131 -- causing incomplete code to be generated. It is better to abort in
8132 -- this case (and we do the abort even with assertions off since the
8133 -- penalty is incorrect code generation).
8135 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8136 raise Program_Error;
8139 -- Free last subprogram name if allocated, and pop scope
8141 Free (SST.Last_Subprogram_Name);
8142 Scope_Stack.Decrement_Last;
8149 procedure Push_Scope (S : Entity_Id) is
8150 E : constant Entity_Id := Scope (S);
8153 if Ekind (S) = E_Void then
8156 -- Set scope depth if not a non-concurrent type, and we have not yet set
8157 -- the scope depth. This means that we have the first occurrence of the
8158 -- scope, and this is where the depth is set.
8160 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8161 and then not Scope_Depth_Set (S)
8163 if S = Standard_Standard then
8164 Set_Scope_Depth_Value (S, Uint_0);
8166 elsif Is_Child_Unit (S) then
8167 Set_Scope_Depth_Value (S, Uint_1);
8169 elsif not Is_Record_Type (Current_Scope) then
8170 if Ekind (S) = E_Loop then
8171 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8173 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8178 Scope_Stack.Increment_Last;
8181 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8185 SST.Save_Scope_Suppress := Scope_Suppress;
8186 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8187 SST.Save_Check_Policy_List := Check_Policy_List;
8188 SST.Save_Default_Storage_Pool := Default_Pool;
8189 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8190 SST.Save_SPARK_Mode := SPARK_Mode;
8191 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8192 SST.Save_Default_SSO := Default_SSO;
8193 SST.Save_Uneval_Old := Uneval_Old;
8195 -- Each new scope pushed onto the scope stack inherits the component
8196 -- alignment of the previous scope. This emulates the "visibility"
8197 -- semantics of pragma Component_Alignment.
8199 if Scope_Stack.Last > Scope_Stack.First then
8200 SST.Component_Alignment_Default :=
8202 (Scope_Stack.Last - 1). Component_Alignment_Default;
8204 -- Otherwise, this is the first scope being pushed on the scope
8205 -- stack. Inherit the component alignment from the configuration
8206 -- form of pragma Component_Alignment (if any).
8209 SST.Component_Alignment_Default :=
8210 Configuration_Component_Alignment;
8213 SST.Last_Subprogram_Name := null;
8214 SST.Is_Transient := False;
8215 SST.Node_To_Be_Wrapped := Empty;
8216 SST.Pending_Freeze_Actions := No_List;
8217 SST.Actions_To_Be_Wrapped := (others => No_List);
8218 SST.First_Use_Clause := Empty;
8219 SST.Is_Active_Stack_Base := False;
8220 SST.Previous_Visibility := False;
8221 SST.Locked_Shared_Objects := No_Elist;
8224 if Debug_Flag_W then
8225 Write_Str ("--> new scope: ");
8226 Write_Name (Chars (Current_Scope));
8227 Write_Str (", Id=");
8228 Write_Int (Int (Current_Scope));
8229 Write_Str (", Depth=");
8230 Write_Int (Int (Scope_Stack.Last));
8234 -- Deal with copying flags from the previous scope to this one. This is
8235 -- not necessary if either scope is standard, or if the new scope is a
8238 if S /= Standard_Standard
8239 and then Scope (S) /= Standard_Standard
8240 and then not Is_Child_Unit (S)
8242 if Nkind (E) not in N_Entity then
8246 -- Copy categorization flags from Scope (S) to S, this is not done
8247 -- when Scope (S) is Standard_Standard since propagation is from
8248 -- library unit entity inwards. Copy other relevant attributes as
8249 -- well (Discard_Names in particular).
8251 -- We only propagate inwards for library level entities,
8252 -- inner level subprograms do not inherit the categorization.
8254 if Is_Library_Level_Entity (S) then
8255 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8256 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8257 Set_Discard_Names (S, Discard_Names (E));
8258 Set_Suppress_Value_Tracking_On_Call
8259 (S, Suppress_Value_Tracking_On_Call (E));
8260 Set_Categorization_From_Scope (E => S, Scop => E);
8264 if Is_Child_Unit (S)
8265 and then Present (E)
8266 and then Ekind_In (E, E_Package, E_Generic_Package)
8268 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8271 Aux : constant Node_Id :=
8272 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8274 if Present (Default_Storage_Pool (Aux)) then
8275 Default_Pool := Default_Storage_Pool (Aux);
8281 ---------------------
8282 -- Premature_Usage --
8283 ---------------------
8285 procedure Premature_Usage (N : Node_Id) is
8286 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8287 E : Entity_Id := Entity (N);
8290 -- Within an instance, the analysis of the actual for a formal object
8291 -- does not see the name of the object itself. This is significant only
8292 -- if the object is an aggregate, where its analysis does not do any
8293 -- name resolution on component associations. (see 4717-008). In such a
8294 -- case, look for the visible homonym on the chain.
8296 if In_Instance and then Present (Homonym (E)) then
8298 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8304 Set_Etype (N, Etype (E));
8309 if Kind = N_Component_Declaration then
8311 ("component&! cannot be used before end of record declaration", N);
8313 elsif Kind = N_Parameter_Specification then
8315 ("formal parameter&! cannot be used before end of specification",
8318 elsif Kind = N_Discriminant_Specification then
8320 ("discriminant&! cannot be used before end of discriminant part",
8323 elsif Kind = N_Procedure_Specification
8324 or else Kind = N_Function_Specification
8327 ("subprogram&! cannot be used before end of its declaration",
8330 elsif Kind = N_Full_Type_Declaration then
8332 ("type& cannot be used before end of its declaration!", N);
8336 ("object& cannot be used before end of its declaration!", N);
8338 end Premature_Usage;
8340 ------------------------
8341 -- Present_System_Aux --
8342 ------------------------
8344 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8346 Aux_Name : Unit_Name_Type;
8347 Unum : Unit_Number_Type;
8352 function Find_System (C_Unit : Node_Id) return Entity_Id;
8353 -- Scan context clause of compilation unit to find with_clause
8360 function Find_System (C_Unit : Node_Id) return Entity_Id is
8361 With_Clause : Node_Id;
8364 With_Clause := First (Context_Items (C_Unit));
8365 while Present (With_Clause) loop
8366 if (Nkind (With_Clause) = N_With_Clause
8367 and then Chars (Name (With_Clause)) = Name_System)
8368 and then Comes_From_Source (With_Clause)
8379 -- Start of processing for Present_System_Aux
8382 -- The child unit may have been loaded and analyzed already
8384 if Present (System_Aux_Id) then
8387 -- If no previous pragma for System.Aux, nothing to load
8389 elsif No (System_Extend_Unit) then
8392 -- Use the unit name given in the pragma to retrieve the unit.
8393 -- Verify that System itself appears in the context clause of the
8394 -- current compilation. If System is not present, an error will
8395 -- have been reported already.
8398 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8400 The_Unit := Unit (Cunit (Current_Sem_Unit));
8404 (Nkind (The_Unit) = N_Package_Body
8405 or else (Nkind (The_Unit) = N_Subprogram_Body
8406 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8408 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8411 if No (With_Sys) and then Present (N) then
8413 -- If we are compiling a subunit, we need to examine its
8414 -- context as well (Current_Sem_Unit is the parent unit);
8416 The_Unit := Parent (N);
8417 while Nkind (The_Unit) /= N_Compilation_Unit loop
8418 The_Unit := Parent (The_Unit);
8421 if Nkind (Unit (The_Unit)) = N_Subunit then
8422 With_Sys := Find_System (The_Unit);
8426 if No (With_Sys) then
8430 Loc := Sloc (With_Sys);
8431 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8432 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8433 Name_Buffer (1 .. 7) := "system.";
8434 Name_Buffer (Name_Len + 8) := '%';
8435 Name_Buffer (Name_Len + 9) := 's
';
8436 Name_Len := Name_Len + 9;
8437 Aux_Name := Name_Find;
8441 (Load_Name => Aux_Name,
8444 Error_Node => With_Sys);
8446 if Unum /= No_Unit then
8447 Semantics (Cunit (Unum));
8449 Defining_Entity (Specification (Unit (Cunit (Unum))));
8452 Make_With_Clause (Loc,
8454 Make_Expanded_Name (Loc,
8455 Chars => Chars (System_Aux_Id),
8456 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8457 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8459 Set_Entity (Name (Withn), System_Aux_Id);
8461 Set_Library_Unit (Withn, Cunit (Unum));
8462 Set_Corresponding_Spec (Withn, System_Aux_Id);
8463 Set_First_Name (Withn, True);
8464 Set_Implicit_With (Withn, True);
8466 Insert_After (With_Sys, Withn);
8467 Mark_Rewrite_Insertion (Withn);
8468 Set_Context_Installed (Withn);
8472 -- Here if unit load failed
8475 Error_Msg_Name_1 := Name_System;
8476 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8478 ("extension package `%.%` does not exist",
8479 Opt.System_Extend_Unit);
8483 end Present_System_Aux;
8485 -------------------------
8486 -- Restore_Scope_Stack --
8487 -------------------------
8489 procedure Restore_Scope_Stack
8491 Handle_Use : Boolean := True)
8493 SS_Last : constant Int := Scope_Stack.Last;
8497 -- Restore visibility of previous scope stack, if any, using the list
8498 -- we saved (we use Remove, since this list will not be used again).
8501 Elmt := Last_Elmt (List);
8502 exit when Elmt = No_Elmt;
8503 Set_Is_Immediately_Visible (Node (Elmt));
8504 Remove_Last_Elmt (List);
8507 -- Restore use clauses
8509 if SS_Last >= Scope_Stack.First
8510 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8513 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8515 end Restore_Scope_Stack;
8517 ----------------------
8518 -- Save_Scope_Stack --
8519 ----------------------
8521 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8522 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8523 -- from immediate visibility entities and Restore_Scope_Stack took care
8524 -- of restoring their visibility analyzing the context of each entity. The
8525 -- problem of such approach is that it was fragile and caused unexpected
8526 -- visibility problems, and indeed one test was found where there was a
8529 -- Furthermore, the following experiment was carried out:
8531 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8532 -- entities whose attribute Is_Immediately_Visible is modified
8533 -- from True to False.
8535 -- - Restore_Scope_Stack was modified to store in another Elist2
8536 -- all the entities whose attribute Is_Immediately_Visible is
8537 -- modified from False to True.
8539 -- - Extra code was added to verify that all the elements of Elist1
8540 -- are found in Elist2
8542 -- This test shows that there may be more occurrences of this problem which
8543 -- have not yet been detected. As a result, we replaced that approach by
8544 -- the current one in which Save_Scope_Stack returns the list of entities
8545 -- whose visibility is changed, and that list is passed to Restore_Scope_
8546 -- Stack to undo that change. This approach is simpler and safer, although
8547 -- it consumes more memory.
8549 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8550 Result : constant Elist_Id := New_Elmt_List;
8553 SS_Last : constant Int := Scope_Stack.Last;
8555 procedure Remove_From_Visibility (E : Entity_Id);
8556 -- If E is immediately visible then append it to the result and remove
8557 -- it temporarily from visibility.
8559 ----------------------------
8560 -- Remove_From_Visibility --
8561 ----------------------------
8563 procedure Remove_From_Visibility (E : Entity_Id) is
8565 if Is_Immediately_Visible (E) then
8566 Append_Elmt (E, Result);
8567 Set_Is_Immediately_Visible (E, False);
8569 end Remove_From_Visibility;
8571 -- Start of processing for Save_Scope_Stack
8574 if SS_Last >= Scope_Stack.First
8575 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8578 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8581 -- If the call is from within a compilation unit, as when called from
8582 -- Rtsfind, make current entries in scope stack invisible while we
8583 -- analyze the new unit.
8585 for J in reverse 0 .. SS_Last loop
8586 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8587 or else No (Scope_Stack.Table (J).Entity);
8589 S := Scope_Stack.Table (J).Entity;
8591 Remove_From_Visibility (S);
8593 E := First_Entity (S);
8594 while Present (E) loop
8595 Remove_From_Visibility (E);
8603 end Save_Scope_Stack;
8609 procedure Set_Use (L : List_Id) is
8611 Pack_Name : Node_Id;
8618 while Present (Decl) loop
8619 if Nkind (Decl) = N_Use_Package_Clause then
8620 Chain_Use_Clause (Decl);
8622 Pack_Name := First (Names (Decl));
8623 while Present (Pack_Name) loop
8624 Pack := Entity (Pack_Name);
8626 if Ekind (Pack) = E_Package
8627 and then Applicable_Use (Pack_Name)
8629 Use_One_Package (Pack, Decl);
8635 elsif Nkind (Decl) = N_Use_Type_Clause then
8636 Chain_Use_Clause (Decl);
8638 Id := First (Subtype_Marks (Decl));
8639 while Present (Id) loop
8640 if Entity (Id) /= Any_Type then
8653 ---------------------
8654 -- Use_One_Package --
8655 ---------------------
8657 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8660 Current_Instance : Entity_Id := Empty;
8662 Private_With_OK : Boolean := False;
8665 if Ekind (P) /= E_Package then
8670 Set_Current_Use_Clause (P, N);
8672 -- Ada 2005 (AI-50217): Check restriction
8674 if From_Limited_With (P) then
8675 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8678 -- Find enclosing instance, if any
8681 Current_Instance := Current_Scope;
8682 while not Is_Generic_Instance (Current_Instance) loop
8683 Current_Instance := Scope (Current_Instance);
8686 if No (Hidden_By_Use_Clause (N)) then
8687 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8691 -- If unit is a package renaming, indicate that the renamed
8692 -- package is also in use (the flags on both entities must
8693 -- remain consistent, and a subsequent use of either of them
8694 -- should be recognized as redundant).
8696 if Present (Renamed_Object (P)) then
8697 Set_In_Use (Renamed_Object (P));
8698 Set_Current_Use_Clause (Renamed_Object (P), N);
8699 Real_P := Renamed_Object (P);
8704 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8705 -- found in the private part of a package specification
8707 if In_Private_Part (Current_Scope)
8708 and then Has_Private_With (P)
8709 and then Is_Child_Unit (Current_Scope)
8710 and then Is_Child_Unit (P)
8711 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8713 Private_With_OK := True;
8716 -- Loop through entities in one package making them potentially
8719 Id := First_Entity (P);
8721 and then (Id /= First_Private_Entity (P)
8722 or else Private_With_OK) -- Ada 2005 (AI-262)
8724 Prev := Current_Entity (Id);
8725 while Present (Prev) loop
8726 if Is_Immediately_Visible (Prev)
8727 and then (not Is_Overloadable (Prev)
8728 or else not Is_Overloadable (Id)
8729 or else (Type_Conformant (Id, Prev)))
8731 if No (Current_Instance) then
8733 -- Potentially use-visible entity remains hidden
8735 goto Next_Usable_Entity;
8737 -- A use clause within an instance hides outer global entities,
8738 -- which are not used to resolve local entities in the
8739 -- instance. Note that the predefined entities in Standard
8740 -- could not have been hidden in the generic by a use clause,
8741 -- and therefore remain visible. Other compilation units whose
8742 -- entities appear in Standard must be hidden in an instance.
8744 -- To determine whether an entity is external to the instance
8745 -- we compare the scope depth of its scope with that of the
8746 -- current instance. However, a generic actual of a subprogram
8747 -- instance is declared in the wrapper package but will not be
8748 -- hidden by a use-visible entity. similarly, an entity that is
8749 -- declared in an enclosing instance will not be hidden by an
8750 -- an entity declared in a generic actual, which can only have
8751 -- been use-visible in the generic and will not have hidden the
8752 -- entity in the generic parent.
8754 -- If Id is called Standard, the predefined package with the
8755 -- same name is in the homonym chain. It has to be ignored
8756 -- because it has no defined scope (being the only entity in
8757 -- the system with this mandated behavior).
8759 elsif not Is_Hidden (Id)
8760 and then Present (Scope (Prev))
8761 and then not Is_Wrapper_Package (Scope (Prev))
8762 and then Scope_Depth (Scope (Prev)) <
8763 Scope_Depth (Current_Instance)
8764 and then (Scope (Prev) /= Standard_Standard
8765 or else Sloc (Prev) > Standard_Location)
8767 if In_Open_Scopes (Scope (Prev))
8768 and then Is_Generic_Instance (Scope (Prev))
8769 and then Present (Associated_Formal_Package (P))
8774 Set_Is_Potentially_Use_Visible (Id);
8775 Set_Is_Immediately_Visible (Prev, False);
8776 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8780 -- A user-defined operator is not use-visible if the predefined
8781 -- operator for the type is immediately visible, which is the case
8782 -- if the type of the operand is in an open scope. This does not
8783 -- apply to user-defined operators that have operands of different
8784 -- types, because the predefined mixed mode operations (multiply
8785 -- and divide) apply to universal types and do not hide anything.
8787 elsif Ekind (Prev) = E_Operator
8788 and then Operator_Matches_Spec (Prev, Id)
8789 and then In_Open_Scopes
8790 (Scope (Base_Type (Etype (First_Formal (Id)))))
8791 and then (No (Next_Formal (First_Formal (Id)))
8792 or else Etype (First_Formal (Id)) =
8793 Etype (Next_Formal (First_Formal (Id)))
8794 or else Chars (Prev) = Name_Op_Expon)
8796 goto Next_Usable_Entity;
8798 -- In an instance, two homonyms may become use_visible through the
8799 -- actuals of distinct formal packages. In the generic, only the
8800 -- current one would have been visible, so make the other one
8803 elsif Present (Current_Instance)
8804 and then Is_Potentially_Use_Visible (Prev)
8805 and then not Is_Overloadable (Prev)
8806 and then Scope (Id) /= Scope (Prev)
8807 and then Used_As_Generic_Actual (Scope (Prev))
8808 and then Used_As_Generic_Actual (Scope (Id))
8809 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8810 Current_Use_Clause (Scope (Id)))
8812 Set_Is_Potentially_Use_Visible (Prev, False);
8813 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8816 Prev := Homonym (Prev);
8819 -- On exit, we know entity is not hidden, unless it is private
8821 if not Is_Hidden (Id)
8822 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8824 Set_Is_Potentially_Use_Visible (Id);
8826 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8827 Set_Is_Potentially_Use_Visible (Full_View (Id));
8831 <<Next_Usable_Entity>>
8835 -- Child units are also made use-visible by a use clause, but they may
8836 -- appear after all visible declarations in the parent entity list.
8838 while Present (Id) loop
8839 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8840 Set_Is_Potentially_Use_Visible (Id);
8846 if Chars (Real_P) = Name_System
8847 and then Scope (Real_P) = Standard_Standard
8848 and then Present_System_Aux (N)
8850 Use_One_Package (System_Aux_Id, N);
8853 end Use_One_Package;
8859 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8861 Is_Known_Used : Boolean;
8865 function Spec_Reloaded_For_Body return Boolean;
8866 -- Determine whether the compilation unit is a package body and the use
8867 -- type clause is in the spec of the same package. Even though the spec
8868 -- was analyzed first, its context is reloaded when analysing the body.
8870 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8871 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8872 -- class-wide operations of ancestor types are use-visible if the
8873 -- ancestor type is visible.
8875 ----------------------------
8876 -- Spec_Reloaded_For_Body --
8877 ----------------------------
8879 function Spec_Reloaded_For_Body return Boolean is
8881 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8883 Spec : constant Node_Id :=
8884 Parent (List_Containing (Parent (Id)));
8887 -- Check whether type is declared in a package specification,
8888 -- and current unit is the corresponding package body. The
8889 -- use clauses themselves may be within a nested package.
8892 Nkind (Spec) = N_Package_Specification
8894 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8895 Cunit_Entity (Current_Sem_Unit));
8900 end Spec_Reloaded_For_Body;
8902 -------------------------------
8903 -- Use_Class_Wide_Operations --
8904 -------------------------------
8906 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8910 function Is_Class_Wide_Operation_Of
8912 T : Entity_Id) return Boolean;
8913 -- Determine whether a subprogram has a class-wide parameter or
8914 -- result that is T'Class.
8916 ---------------------------------
8917 -- Is_Class_Wide_Operation_Of --
8918 ---------------------------------
8920 function Is_Class_Wide_Operation_Of
8922 T : Entity_Id) return Boolean
8927 Formal := First_Formal (Op);
8928 while Present (Formal) loop
8929 if Etype (Formal) = Class_Wide_Type (T) then
8932 Next_Formal (Formal);
8935 if Etype (Op) = Class_Wide_Type (T) then
8940 end Is_Class_Wide_Operation_Of;
8942 -- Start of processing for Use_Class_Wide_Operations
8945 Scop := Scope (Typ);
8946 if not Is_Hidden (Scop) then
8947 Ent := First_Entity (Scop);
8948 while Present (Ent) loop
8949 if Is_Overloadable (Ent)
8950 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8951 and then not Is_Potentially_Use_Visible (Ent)
8953 Set_Is_Potentially_Use_Visible (Ent);
8954 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8961 if Is_Derived_Type (Typ) then
8962 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8964 end Use_Class_Wide_Operations;
8966 -- Start of processing for Use_One_Type
8969 -- It is the type determined by the subtype mark (8.4(8)) whose
8970 -- operations become potentially use-visible.
8972 T := Base_Type (Entity (Id));
8974 -- Either the type itself is used, the package where it is declared
8975 -- is in use or the entity is declared in the current package, thus
8980 or else In_Use (Scope (T))
8981 or else Scope (T) = Current_Scope;
8983 Set_Redundant_Use (Id,
8984 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8986 if Ekind (T) = E_Incomplete_Type then
8987 Error_Msg_N ("premature usage of incomplete type", Id);
8989 elsif In_Open_Scopes (Scope (T)) then
8992 -- A limited view cannot appear in a use_type clause. However, an access
8993 -- type whose designated type is limited has the flag but is not itself
8994 -- a limited view unless we only have a limited view of its enclosing
8997 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8999 ("incomplete type from limited view "
9000 & "cannot appear in use clause", Id);
9002 -- If the subtype mark designates a subtype in a different package,
9003 -- we have to check that the parent type is visible, otherwise the
9004 -- use type clause is a noop. Not clear how to do that???
9006 elsif not Redundant_Use (Id) then
9009 -- If T is tagged, primitive operators on class-wide operands
9010 -- are also available.
9012 if Is_Tagged_Type (T) then
9013 Set_In_Use (Class_Wide_Type (T));
9016 Set_Current_Use_Clause (T, Parent (Id));
9018 -- Iterate over primitive operations of the type. If an operation is
9019 -- already use_visible, it is the result of a previous use_clause,
9020 -- and already appears on the corresponding entity chain. If the
9021 -- clause is being reinstalled, operations are already use-visible.
9027 Op_List := Collect_Primitive_Operations (T);
9028 Elmt := First_Elmt (Op_List);
9029 while Present (Elmt) loop
9030 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
9031 or else Chars (Node (Elmt)) in Any_Operator_Name)
9032 and then not Is_Hidden (Node (Elmt))
9033 and then not Is_Potentially_Use_Visible (Node (Elmt))
9035 Set_Is_Potentially_Use_Visible (Node (Elmt));
9036 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9038 elsif Ada_Version >= Ada_2012
9039 and then All_Present (Parent (Id))
9040 and then not Is_Hidden (Node (Elmt))
9041 and then not Is_Potentially_Use_Visible (Node (Elmt))
9043 Set_Is_Potentially_Use_Visible (Node (Elmt));
9044 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9051 if Ada_Version >= Ada_2012
9052 and then All_Present (Parent (Id))
9053 and then Is_Tagged_Type (T)
9055 Use_Class_Wide_Operations (T);
9059 -- If warning on redundant constructs, check for unnecessary WITH
9061 if Warn_On_Redundant_Constructs
9062 and then Is_Known_Used
9064 -- with P; with P; use P;
9065 -- package P is package X is package body X is
9066 -- type T ... use P.T;
9068 -- The compilation unit is the body of X. GNAT first compiles the
9069 -- spec of X, then proceeds to the body. At that point P is marked
9070 -- as use visible. The analysis then reinstalls the spec along with
9071 -- its context. The use clause P.T is now recognized as redundant,
9072 -- but in the wrong context. Do not emit a warning in such cases.
9073 -- Do not emit a warning either if we are in an instance, there is
9074 -- no redundancy between an outer use_clause and one that appears
9075 -- within the generic.
9077 and then not Spec_Reloaded_For_Body
9078 and then not In_Instance
9080 -- The type already has a use clause
9084 -- Case where we know the current use clause for the type
9086 if Present (Current_Use_Clause (T)) then
9087 Use_Clause_Known : declare
9088 Clause1 : constant Node_Id := Parent (Id);
9089 Clause2 : constant Node_Id := Current_Use_Clause (T);
9096 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9097 -- Return the appropriate entity for determining which unit
9098 -- has a deeper scope: the defining entity for U, unless U
9099 -- is a package instance, in which case we retrieve the
9100 -- entity of the instance spec.
9102 --------------------
9103 -- Entity_Of_Unit --
9104 --------------------
9106 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9108 if Nkind (U) = N_Package_Instantiation
9109 and then Analyzed (U)
9111 return Defining_Entity (Instance_Spec (U));
9113 return Defining_Entity (U);
9117 -- Start of processing for Use_Clause_Known
9120 -- If both current use type clause and the use type clause
9121 -- for the type are at the compilation unit level, one of
9122 -- the units must be an ancestor of the other, and the
9123 -- warning belongs on the descendant.
9125 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9127 Nkind (Parent (Clause2)) = N_Compilation_Unit
9129 -- If the unit is a subprogram body that acts as spec,
9130 -- the context clause is shared with the constructed
9131 -- subprogram spec. Clearly there is no redundancy.
9133 if Clause1 = Clause2 then
9137 Unit1 := Unit (Parent (Clause1));
9138 Unit2 := Unit (Parent (Clause2));
9140 -- If both clauses are on same unit, or one is the body
9141 -- of the other, or one of them is in a subunit, report
9142 -- redundancy on the later one.
9144 if Unit1 = Unit2 then
9145 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9146 Error_Msg_NE -- CODEFIX
9147 ("& is already use-visible through previous "
9148 & "use_type_clause #??", Clause1, T);
9151 elsif Nkind (Unit1) = N_Subunit then
9152 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9153 Error_Msg_NE -- CODEFIX
9154 ("& is already use-visible through previous "
9155 & "use_type_clause #??", Clause1, T);
9158 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9159 and then Nkind (Unit1) /= Nkind (Unit2)
9160 and then Nkind (Unit1) /= N_Subunit
9162 Error_Msg_Sloc := Sloc (Clause1);
9163 Error_Msg_NE -- CODEFIX
9164 ("& is already use-visible through previous "
9165 & "use_type_clause #??", Current_Use_Clause (T), T);
9169 -- There is a redundant use type clause in a child unit.
9170 -- Determine which of the units is more deeply nested.
9171 -- If a unit is a package instance, retrieve the entity
9172 -- and its scope from the instance spec.
9174 Ent1 := Entity_Of_Unit (Unit1);
9175 Ent2 := Entity_Of_Unit (Unit2);
9177 if Scope (Ent2) = Standard_Standard then
9178 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9181 elsif Scope (Ent1) = Standard_Standard then
9182 Error_Msg_Sloc := Sloc (Id);
9185 -- If both units are child units, we determine which one
9186 -- is the descendant by the scope distance to the
9187 -- ultimate parent unit.
9197 and then Present (S2)
9198 and then S1 /= Standard_Standard
9199 and then S2 /= Standard_Standard
9205 if S1 = Standard_Standard then
9206 Error_Msg_Sloc := Sloc (Id);
9209 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9215 Error_Msg_NE -- CODEFIX
9216 ("& is already use-visible through previous "
9217 & "use_type_clause #??", Err_No, Id);
9219 -- Case where current use type clause and the use type
9220 -- clause for the type are not both at the compilation unit
9221 -- level. In this case we don't have location information.
9224 Error_Msg_NE -- CODEFIX
9225 ("& is already use-visible through previous "
9226 & "use type clause??", Id, T);
9228 end Use_Clause_Known;
9230 -- Here if Current_Use_Clause is not set for T, another case
9231 -- where we do not have the location information available.
9234 Error_Msg_NE -- CODEFIX
9235 ("& is already use-visible through previous "
9236 & "use type clause??", Id, T);
9239 -- The package where T is declared is already used
9241 elsif In_Use (Scope (T)) then
9242 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9243 Error_Msg_NE -- CODEFIX
9244 ("& is already use-visible through package use clause #??",
9247 -- The current scope is the package where T is declared
9250 Error_Msg_Node_2 := Scope (T);
9251 Error_Msg_NE -- CODEFIX
9252 ("& is already use-visible inside package &??", Id, T);
9261 procedure Write_Info is
9262 Id : Entity_Id := First_Entity (Current_Scope);
9265 -- No point in dumping standard entities
9267 if Current_Scope = Standard_Standard then
9271 Write_Str ("========================================================");
9273 Write_Str (" Defined Entities in ");
9274 Write_Name (Chars (Current_Scope));
9276 Write_Str ("========================================================");
9280 Write_Str ("-- none --");
9284 while Present (Id) loop
9285 Write_Entity_Info (Id, " ");
9290 if Scope (Current_Scope) = Standard_Standard then
9292 -- Print information on the current unit itself
9294 Write_Entity_Info (Current_Scope, " ");
9307 for J in reverse 1 .. Scope_Stack.Last loop
9308 S := Scope_Stack.Table (J).Entity;
9309 Write_Int (Int (S));
9310 Write_Str (" === ");
9311 Write_Name (Chars (S));
9320 procedure we (S : Entity_Id) is
9323 E := First_Entity (S);
9324 while Present (E) loop
9325 Write_Int (Int (E));
9326 Write_Str (" === ");
9327 Write_Name (Chars (E));