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 -- Ada 2005 (AI-231): In the case where the type is defined by an
1026 -- access_definition, the renamed entity shall be of an access-to-
1027 -- constant type if and only if the access_definition defines an
1028 -- access-to-constant type. ARM 8.5.1(4)
1030 if Constant_Present
(Access_Definition
(N
))
1031 and then not Is_Access_Constant
(Etype
(Nam
))
1033 Error_Msg_N
("(Ada 2005): the renamed object is not "
1034 & "access-to-constant (RM 8.5.1(6))", N
);
1036 elsif not Constant_Present
(Access_Definition
(N
))
1037 and then Is_Access_Constant
(Etype
(Nam
))
1039 Error_Msg_N
("(Ada 2005): the renamed object is not "
1040 & "access-to-variable (RM 8.5.1(6))", N
);
1043 if Is_Access_Subprogram_Type
(Etype
(Nam
)) then
1044 Check_Subtype_Conformant
1045 (Designated_Type
(T
), Designated_Type
(Etype
(Nam
)));
1047 elsif not Subtypes_Statically_Match
1048 (Designated_Type
(T
),
1049 Available_View
(Designated_Type
(Etype
(Nam
))))
1052 ("subtype of renamed object does not statically match", N
);
1056 -- Special processing for renaming function return object. Some errors
1057 -- and warnings are produced only for calls that come from source.
1059 if Nkind
(Nam
) = N_Function_Call
then
1062 -- Usage is illegal in Ada 83, but renamings are also introduced
1063 -- during expansion, and error does not apply to those.
1066 if Comes_From_Source
(N
) then
1068 ("(Ada 83) cannot rename function return object", Nam
);
1071 -- In Ada 95, warn for odd case of renaming parameterless function
1072 -- call if this is not a limited type (where this is useful).
1075 if Warn_On_Object_Renames_Function
1076 and then No
(Parameter_Associations
(Nam
))
1077 and then not Is_Limited_Type
(Etype
(Nam
))
1078 and then Comes_From_Source
(Nam
)
1081 ("renaming function result object is suspicious?R?", Nam
);
1083 ("\function & will be called only once?R?", Nam
,
1084 Entity
(Name
(Nam
)));
1085 Error_Msg_N
-- CODEFIX
1086 ("\suggest using an initialized constant "
1087 & "object instead?R?", Nam
);
1093 Check_Constrained_Object
;
1095 -- An object renaming requires an exact match of the type. Class-wide
1096 -- matching is not allowed.
1098 if Is_Class_Wide_Type
(T
)
1099 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
1101 Wrong_Type
(Nam
, T
);
1106 -- Ada 2005 (AI-326): Handle wrong use of incomplete type
1108 if Nkind
(Nam
) = N_Explicit_Dereference
1109 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
1111 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
1114 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
1115 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
1119 -- Ada 2005 (AI-327)
1121 if Ada_Version
>= Ada_2005
1122 and then Nkind
(Nam
) = N_Attribute_Reference
1123 and then Attribute_Name
(Nam
) = Name_Priority
1127 elsif Ada_Version
>= Ada_2005
and then Nkind
(Nam
) in N_Has_Entity
then
1130 Nam_Ent
: Entity_Id
;
1133 if Nkind
(Nam
) = N_Attribute_Reference
then
1134 Nam_Ent
:= Entity
(Prefix
(Nam
));
1136 Nam_Ent
:= Entity
(Nam
);
1139 Nam_Decl
:= Parent
(Nam_Ent
);
1141 if Has_Null_Exclusion
(N
)
1142 and then not Has_Null_Exclusion
(Nam_Decl
)
1144 -- Ada 2005 (AI-423): If the object name denotes a generic
1145 -- formal object of a generic unit G, and the object renaming
1146 -- declaration occurs within the body of G or within the body
1147 -- of a generic unit declared within the declarative region
1148 -- of G, then the declaration of the formal object of G must
1149 -- have a null exclusion or a null-excluding subtype.
1151 if Is_Formal_Object
(Nam_Ent
)
1152 and then In_Generic_Scope
(Id
)
1154 if not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1156 ("renamed formal does not exclude `NULL` "
1157 & "(RM 8.5.1(4.6/2))", N
);
1159 elsif In_Package_Body
(Scope
(Id
)) then
1161 ("formal object does not have a null exclusion"
1162 & "(RM 8.5.1(4.6/2))", N
);
1165 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
1166 -- shall exclude null.
1168 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
1170 ("renamed object does not exclude `NULL` "
1171 & "(RM 8.5.1(4.6/2))", N
);
1173 -- An instance is illegal if it contains a renaming that
1174 -- excludes null, and the actual does not. The renaming
1175 -- declaration has already indicated that the declaration
1176 -- of the renamed actual in the instance will raise
1177 -- constraint_error.
1179 elsif Nkind
(Nam_Decl
) = N_Object_Declaration
1180 and then In_Instance
1182 Present
(Corresponding_Generic_Association
(Nam_Decl
))
1183 and then Nkind
(Expression
(Nam_Decl
)) =
1184 N_Raise_Constraint_Error
1187 ("renamed actual does not exclude `NULL` "
1188 & "(RM 8.5.1(4.6/2))", N
);
1190 -- Finally, if there is a null exclusion, the subtype mark
1191 -- must not be null-excluding.
1193 elsif No
(Access_Definition
(N
))
1194 and then Can_Never_Be_Null
(T
)
1197 ("`NOT NULL` not allowed (& already excludes null)",
1202 elsif Can_Never_Be_Null
(T
)
1203 and then not Can_Never_Be_Null
(Etype
(Nam_Ent
))
1206 ("renamed object does not exclude `NULL` "
1207 & "(RM 8.5.1(4.6/2))", N
);
1209 elsif Has_Null_Exclusion
(N
)
1210 and then No
(Access_Definition
(N
))
1211 and then Can_Never_Be_Null
(T
)
1214 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
1219 -- Set the Ekind of the entity, unless it has been set already, as is
1220 -- the case for the iteration object over a container with no variable
1221 -- indexing. In that case it's been marked as a constant, and we do not
1222 -- want to change it to a variable.
1224 if Ekind
(Id
) /= E_Constant
then
1225 Set_Ekind
(Id
, E_Variable
);
1228 -- Initialize the object size and alignment. Note that we used to call
1229 -- Init_Size_Align here, but that's wrong for objects which have only
1230 -- an Esize, not an RM_Size field.
1232 Init_Object_Size_Align
(Id
);
1234 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
1237 -- Verify that the renamed entity is an object or a function call. It
1238 -- may have been rewritten in several ways.
1240 elsif Is_Object_Reference
(Nam
) then
1241 if Comes_From_Source
(N
) then
1242 if Is_Dependent_Component_Of_Mutable_Object
(Nam
) then
1244 ("illegal renaming of discriminant-dependent component", Nam
);
1247 -- If the renaming comes from source and the renamed object is a
1248 -- dereference, then mark the prefix as needing debug information,
1249 -- since it might have been rewritten hence internally generated
1250 -- and Debug_Renaming_Declaration will link the renaming to it.
1252 if Nkind
(Nam
) = N_Explicit_Dereference
1253 and then Is_Entity_Name
(Prefix
(Nam
))
1255 Set_Debug_Info_Needed
(Entity
(Prefix
(Nam
)));
1259 -- A static function call may have been folded into a literal
1261 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
1263 -- When expansion is disabled, attribute reference is not rewritten
1264 -- as function call. Otherwise it may be rewritten as a conversion,
1265 -- so check original node.
1267 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
1268 and then Is_Function_Attribute_Name
1269 (Attribute_Name
(Original_Node
(Nam
))))
1271 -- Weird but legal, equivalent to renaming a function call. Illegal
1272 -- if the literal is the result of constant-folding an attribute
1273 -- reference that is not a function.
1275 or else (Is_Entity_Name
(Nam
)
1276 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
1278 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
1280 or else (Nkind
(Nam
) = N_Type_Conversion
1281 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
1285 elsif Nkind
(Nam
) = N_Type_Conversion
then
1287 ("renaming of conversion only allowed for tagged types", Nam
);
1289 -- Ada 2005 (AI-327)
1291 elsif Ada_Version
>= Ada_2005
1292 and then Nkind
(Nam
) = N_Attribute_Reference
1293 and then Attribute_Name
(Nam
) = Name_Priority
1297 -- Allow internally generated x'Ref resulting in N_Reference node
1299 elsif Nkind
(Nam
) = N_Reference
then
1303 Error_Msg_N
("expect object name in renaming", Nam
);
1308 if not Is_Variable
(Nam
) then
1309 Set_Ekind
(Id
, E_Constant
);
1310 Set_Never_Set_In_Source
(Id
, True);
1311 Set_Is_True_Constant
(Id
, True);
1314 -- The object renaming declaration may become Ghost if it renames a
1317 if Is_Entity_Name
(Nam
) then
1318 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
1321 -- The entity of the renaming declaration needs to reflect whether the
1322 -- renamed object is volatile. Is_Volatile is set if the renamed object
1323 -- is volatile in the RM legality sense.
1325 Set_Is_Volatile
(Id
, Is_Volatile_Object
(Nam
));
1327 -- Also copy settings of Atomic/Independent/Volatile_Full_Access
1329 if Is_Entity_Name
(Nam
) then
1330 Set_Is_Atomic
(Id
, Is_Atomic
(Entity
(Nam
)));
1331 Set_Is_Independent
(Id
, Is_Independent
(Entity
(Nam
)));
1332 Set_Is_Volatile_Full_Access
(Id
,
1333 Is_Volatile_Full_Access
(Entity
(Nam
)));
1336 -- Treat as volatile if we just set the Volatile flag
1340 -- Or if we are renaming an entity which was marked this way
1342 -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ???
1344 or else (Is_Entity_Name
(Nam
)
1345 and then Treat_As_Volatile
(Entity
(Nam
)))
1347 Set_Treat_As_Volatile
(Id
, True);
1350 -- Now make the link to the renamed object
1352 Set_Renamed_Object
(Id
, Nam
);
1354 -- Implementation-defined aspect specifications can appear in a renaming
1355 -- declaration, but not language-defined ones. The call to procedure
1356 -- Analyze_Aspect_Specifications will take care of this error check.
1358 if Has_Aspects
(N
) then
1359 Analyze_Aspect_Specifications
(N
, Id
);
1362 -- Deal with dimensions
1364 Analyze_Dimension
(N
);
1365 end Analyze_Object_Renaming
;
1367 ------------------------------
1368 -- Analyze_Package_Renaming --
1369 ------------------------------
1371 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
1372 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
1377 if Name
(N
) = Error
then
1381 -- Check for Text_IO special unit (we may be renaming a Text_IO child)
1383 Check_Text_IO_Special_Unit
(Name
(N
));
1385 if Current_Scope
/= Standard_Standard
then
1386 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1392 if Is_Entity_Name
(Name
(N
)) then
1393 Old_P
:= Entity
(Name
(N
));
1398 if Etype
(Old_P
) = Any_Type
then
1399 Error_Msg_N
("expect package name in renaming", Name
(N
));
1401 elsif Ekind
(Old_P
) /= E_Package
1402 and then not (Ekind
(Old_P
) = E_Generic_Package
1403 and then In_Open_Scopes
(Old_P
))
1405 if Ekind
(Old_P
) = E_Generic_Package
then
1407 ("generic package cannot be renamed as a package", Name
(N
));
1409 Error_Msg_Sloc
:= Sloc
(Old_P
);
1411 ("expect package name in renaming, found& declared#",
1415 -- Set basic attributes to minimize cascaded errors
1417 Set_Ekind
(New_P
, E_Package
);
1418 Set_Etype
(New_P
, Standard_Void_Type
);
1420 -- Here for OK package renaming
1423 -- Entities in the old package are accessible through the renaming
1424 -- entity. The simplest implementation is to have both packages share
1427 Set_Ekind
(New_P
, E_Package
);
1428 Set_Etype
(New_P
, Standard_Void_Type
);
1430 if Present
(Renamed_Object
(Old_P
)) then
1431 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1433 Set_Renamed_Object
(New_P
, Old_P
);
1436 Set_Has_Completion
(New_P
);
1438 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1439 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1440 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1441 Check_Library_Unit_Renaming
(N
, Old_P
);
1442 Generate_Reference
(Old_P
, Name
(N
));
1444 -- The package renaming declaration may become Ghost if it renames a
1447 Mark_Renaming_As_Ghost
(N
, Old_P
);
1449 -- If the renaming is in the visible part of a package, then we set
1450 -- Renamed_In_Spec for the renamed package, to prevent giving
1451 -- warnings about no entities referenced. Such a warning would be
1452 -- overenthusiastic, since clients can see entities in the renamed
1453 -- package via the visible package renaming.
1456 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1458 if Ekind
(Ent
) = E_Package
1459 and then not In_Private_Part
(Ent
)
1460 and then In_Extended_Main_Source_Unit
(N
)
1461 and then Ekind
(Old_P
) = E_Package
1463 Set_Renamed_In_Spec
(Old_P
);
1467 -- If this is the renaming declaration of a package instantiation
1468 -- within itself, it is the declaration that ends the list of actuals
1469 -- for the instantiation. At this point, the subtypes that rename
1470 -- the actuals are flagged as generic, to avoid spurious ambiguities
1471 -- if the actuals for two distinct formals happen to coincide. If
1472 -- the actual is a private type, the subtype has a private completion
1473 -- that is flagged in the same fashion.
1475 -- Resolution is identical to what is was in the original generic.
1476 -- On exit from the generic instance, these are turned into regular
1477 -- subtypes again, so they are compatible with types in their class.
1479 if not Is_Generic_Instance
(Old_P
) then
1482 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1485 if Nkind
(Spec
) = N_Package_Specification
1486 and then Present
(Generic_Parent
(Spec
))
1487 and then Old_P
= Current_Scope
1488 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1494 E
:= First_Entity
(Old_P
);
1495 while Present
(E
) and then E
/= New_P
loop
1497 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1499 Set_Is_Generic_Actual_Type
(E
);
1501 if Is_Private_Type
(E
)
1502 and then Present
(Full_View
(E
))
1504 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1514 -- Implementation-defined aspect specifications can appear in a renaming
1515 -- declaration, but not language-defined ones. The call to procedure
1516 -- Analyze_Aspect_Specifications will take care of this error check.
1518 if Has_Aspects
(N
) then
1519 Analyze_Aspect_Specifications
(N
, New_P
);
1521 end Analyze_Package_Renaming
;
1523 -------------------------------
1524 -- Analyze_Renamed_Character --
1525 -------------------------------
1527 procedure Analyze_Renamed_Character
1532 C
: constant Node_Id
:= Name
(N
);
1535 if Ekind
(New_S
) = E_Function
then
1536 Resolve
(C
, Etype
(New_S
));
1539 Check_Frozen_Renaming
(N
, New_S
);
1543 Error_Msg_N
("character literal can only be renamed as function", N
);
1545 end Analyze_Renamed_Character
;
1547 ---------------------------------
1548 -- Analyze_Renamed_Dereference --
1549 ---------------------------------
1551 procedure Analyze_Renamed_Dereference
1556 Nam
: constant Node_Id
:= Name
(N
);
1557 P
: constant Node_Id
:= Prefix
(Nam
);
1563 if not Is_Overloaded
(P
) then
1564 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1565 or else not Type_Conformant
(Etype
(Nam
), New_S
)
1567 Error_Msg_N
("designated type does not match specification", P
);
1576 Get_First_Interp
(Nam
, Ind
, It
);
1578 while Present
(It
.Nam
) loop
1580 if Ekind
(It
.Nam
) = E_Subprogram_Type
1581 and then Type_Conformant
(It
.Nam
, New_S
)
1583 if Typ
/= Any_Id
then
1584 Error_Msg_N
("ambiguous renaming", P
);
1591 Get_Next_Interp
(Ind
, It
);
1594 if Typ
= Any_Type
then
1595 Error_Msg_N
("designated type does not match specification", P
);
1600 Check_Frozen_Renaming
(N
, New_S
);
1604 end Analyze_Renamed_Dereference
;
1606 ---------------------------
1607 -- Analyze_Renamed_Entry --
1608 ---------------------------
1610 procedure Analyze_Renamed_Entry
1615 Nam
: constant Node_Id
:= Name
(N
);
1616 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1617 Is_Actual
: constant Boolean := Present
(Corresponding_Formal_Spec
(N
));
1621 if Entity
(Sel
) = Any_Id
then
1623 -- Selector is undefined on prefix. Error emitted already
1625 Set_Has_Completion
(New_S
);
1629 -- Otherwise find renamed entity and build body of New_S as a call to it
1631 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1633 if Old_S
= Any_Id
then
1634 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1637 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1638 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1639 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1642 -- Only mode conformance required for a renaming_as_declaration
1644 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1647 Inherit_Renamed_Profile
(New_S
, Old_S
);
1649 -- The prefix can be an arbitrary expression that yields a task or
1650 -- protected object, so it must be resolved.
1652 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1655 Set_Convention
(New_S
, Convention
(Old_S
));
1656 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1658 -- AI05-0225: If the renamed entity is a procedure or entry of a
1659 -- protected object, the target object must be a variable.
1661 if Ekind
(Scope
(Old_S
)) in Protected_Kind
1662 and then Ekind
(New_S
) = E_Procedure
1663 and then not Is_Variable
(Prefix
(Nam
))
1667 ("target object of protected operation used as actual for "
1668 & "formal procedure must be a variable", Nam
);
1671 ("target object of protected operation renamed as procedure, "
1672 & "must be a variable", Nam
);
1677 Check_Frozen_Renaming
(N
, New_S
);
1679 end Analyze_Renamed_Entry
;
1681 -----------------------------------
1682 -- Analyze_Renamed_Family_Member --
1683 -----------------------------------
1685 procedure Analyze_Renamed_Family_Member
1690 Nam
: constant Node_Id
:= Name
(N
);
1691 P
: constant Node_Id
:= Prefix
(Nam
);
1695 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1696 or else (Nkind
(P
) = N_Selected_Component
1697 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1699 if Is_Entity_Name
(P
) then
1700 Old_S
:= Entity
(P
);
1702 Old_S
:= Entity
(Selector_Name
(P
));
1705 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1706 Error_Msg_N
("entry family does not match specification", N
);
1709 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1710 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1711 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1715 Error_Msg_N
("no entry family matches specification", N
);
1718 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1721 Check_Frozen_Renaming
(N
, New_S
);
1723 end Analyze_Renamed_Family_Member
;
1725 -----------------------------------------
1726 -- Analyze_Renamed_Primitive_Operation --
1727 -----------------------------------------
1729 procedure Analyze_Renamed_Primitive_Operation
1738 Ctyp
: Conformance_Type
) return Boolean;
1739 -- Verify that the signatures of the renamed entity and the new entity
1740 -- match. The first formal of the renamed entity is skipped because it
1741 -- is the target object in any subsequent call.
1749 Ctyp
: Conformance_Type
) return Boolean
1755 if Ekind
(Subp
) /= Ekind
(New_S
) then
1759 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1760 New_F
:= First_Formal
(New_S
);
1761 while Present
(Old_F
) and then Present
(New_F
) loop
1762 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1766 if Ctyp
>= Mode_Conformant
1767 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1772 Next_Formal
(New_F
);
1773 Next_Formal
(Old_F
);
1779 -- Start of processing for Analyze_Renamed_Primitive_Operation
1782 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1783 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1785 if not Conforms
(Old_S
, Type_Conformant
) then
1790 -- Find the operation that matches the given signature
1798 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1800 while Present
(It
.Nam
) loop
1801 if Conforms
(It
.Nam
, Type_Conformant
) then
1805 Get_Next_Interp
(Ind
, It
);
1810 if Old_S
= Any_Id
then
1811 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1815 if not Conforms
(Old_S
, Subtype_Conformant
) then
1816 Error_Msg_N
("subtype conformance error in renaming", N
);
1819 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1820 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1823 -- Only mode conformance required for a renaming_as_declaration
1825 if not Conforms
(Old_S
, Mode_Conformant
) then
1826 Error_Msg_N
("mode conformance error in renaming", N
);
1829 -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed
1830 -- view of a subprogram is intrinsic, because the compiler has
1831 -- to generate a wrapper for any call to it. If the name in a
1832 -- subprogram renaming is a prefixed view, the entity is thus
1833 -- intrinsic, and 'Access cannot be applied to it.
1835 Set_Convention
(New_S
, Convention_Intrinsic
);
1838 -- Inherit_Renamed_Profile (New_S, Old_S);
1840 -- The prefix can be an arbitrary expression that yields an
1841 -- object, so it must be resolved.
1843 Resolve
(Prefix
(Name
(N
)));
1845 end Analyze_Renamed_Primitive_Operation
;
1847 ---------------------------------
1848 -- Analyze_Subprogram_Renaming --
1849 ---------------------------------
1851 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1852 Formal_Spec
: constant Entity_Id
:= Corresponding_Formal_Spec
(N
);
1853 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1854 Nam
: constant Node_Id
:= Name
(N
);
1855 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1856 Save_AVP
: constant Node_Id
:= Ada_Version_Pragma
;
1857 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1858 Spec
: constant Node_Id
:= Specification
(N
);
1860 Old_S
: Entity_Id
:= Empty
;
1861 Rename_Spec
: Entity_Id
;
1863 procedure Build_Class_Wide_Wrapper
1864 (Ren_Id
: out Entity_Id
;
1865 Wrap_Id
: out Entity_Id
);
1866 -- Ada 2012 (AI05-0071): A generic/instance scenario involving a formal
1867 -- type with unknown discriminants and a generic primitive operation of
1868 -- the said type with a box require special processing when the actual
1869 -- is a class-wide type:
1872 -- type Formal_Typ (<>) is private;
1873 -- with procedure Prim_Op (Param : Formal_Typ) is <>;
1874 -- package Gen is ...
1876 -- package Inst is new Gen (Actual_Typ'Class);
1878 -- In this case the general renaming mechanism used in the prologue of
1879 -- an instance no longer applies:
1881 -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op;
1883 -- The above is replaced the following wrapper/renaming combination:
1885 -- procedure Wrapper (Param : Formal_Typ) is -- wrapper
1887 -- Prim_Op (Param); -- primitive
1890 -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper;
1892 -- This transformation applies only if there is no explicit visible
1893 -- class-wide operation at the point of the instantiation. Ren_Id is
1894 -- the entity of the renaming declaration. Wrap_Id is the entity of
1895 -- the generated class-wide wrapper (or Any_Id).
1897 procedure Check_Null_Exclusion
1900 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1901 -- following AI rules:
1903 -- If Ren is a renaming of a formal subprogram and one of its
1904 -- parameters has a null exclusion, then the corresponding formal
1905 -- in Sub must also have one. Otherwise the subtype of the Sub's
1906 -- formal parameter must exclude null.
1908 -- If Ren is a renaming of a formal function and its return
1909 -- profile has a null exclusion, then Sub's return profile must
1910 -- have one. Otherwise the subtype of Sub's return profile must
1913 procedure Freeze_Actual_Profile
;
1914 -- In Ada 2012, enforce the freezing rule concerning formal incomplete
1915 -- types: a callable entity freezes its profile, unless it has an
1916 -- incomplete untagged formal (RM 13.14(10.2/3)).
1918 function Has_Class_Wide_Actual
return Boolean;
1919 -- Ada 2012 (AI05-071, AI05-0131): True if N is the renaming for a
1920 -- defaulted formal subprogram where the actual for the controlling
1921 -- formal type is class-wide.
1923 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1924 -- Find renamed entity when the declaration is a renaming_as_body and
1925 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1926 -- rule that a renaming_as_body is illegal if the declaration occurs
1927 -- before the subprogram it completes is frozen, and renaming indirectly
1928 -- renames the subprogram itself.(Defect Report 8652/0027).
1930 ------------------------------
1931 -- Build_Class_Wide_Wrapper --
1932 ------------------------------
1934 procedure Build_Class_Wide_Wrapper
1935 (Ren_Id
: out Entity_Id
;
1936 Wrap_Id
: out Entity_Id
)
1938 Loc
: constant Source_Ptr
:= Sloc
(N
);
1941 (Subp_Id
: Entity_Id
;
1942 Params
: List_Id
) return Node_Id
;
1943 -- Create a dispatching call to invoke routine Subp_Id with actuals
1944 -- built from the parameter specifications of list Params.
1946 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
;
1947 -- Create a subprogram specification based on the subprogram profile
1950 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
;
1951 -- Find a primitive subprogram of type Typ which matches the profile
1952 -- of the renaming declaration.
1954 procedure Interpretation_Error
(Subp_Id
: Entity_Id
);
1955 -- Emit a continuation error message suggesting subprogram Subp_Id as
1956 -- a possible interpretation.
1958 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean;
1959 -- Determine whether subprogram Subp_Id denotes the intrinsic "="
1962 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean;
1963 -- Determine whether subprogram Subp_Id is a suitable candidate for
1964 -- the role of a wrapped subprogram.
1971 (Subp_Id
: Entity_Id
;
1972 Params
: List_Id
) return Node_Id
1974 Actuals
: constant List_Id
:= New_List
;
1975 Call_Ref
: constant Node_Id
:= New_Occurrence_Of
(Subp_Id
, Loc
);
1979 -- Build the actual parameters of the call
1981 Formal
:= First
(Params
);
1982 while Present
(Formal
) loop
1984 Make_Identifier
(Loc
, Chars
(Defining_Identifier
(Formal
))));
1989 -- return Subp_Id (Actuals);
1991 if Ekind_In
(Subp_Id
, E_Function
, E_Operator
) then
1993 Make_Simple_Return_Statement
(Loc
,
1995 Make_Function_Call
(Loc
,
1997 Parameter_Associations
=> Actuals
));
2000 -- Subp_Id (Actuals);
2004 Make_Procedure_Call_Statement
(Loc
,
2006 Parameter_Associations
=> Actuals
);
2014 function Build_Spec
(Subp_Id
: Entity_Id
) return Node_Id
is
2015 Params
: constant List_Id
:= Copy_Parameter_List
(Subp_Id
);
2016 Spec_Id
: constant Entity_Id
:=
2017 Make_Defining_Identifier
(Loc
,
2018 Chars
=> New_External_Name
(Chars
(Subp_Id
), 'R'));
2021 if Ekind
(Formal_Spec
) = E_Procedure
then
2023 Make_Procedure_Specification
(Loc
,
2024 Defining_Unit_Name
=> Spec_Id
,
2025 Parameter_Specifications
=> Params
);
2028 Make_Function_Specification
(Loc
,
2029 Defining_Unit_Name
=> Spec_Id
,
2030 Parameter_Specifications
=> Params
,
2031 Result_Definition
=>
2032 New_Copy_Tree
(Result_Definition
(Spec
)));
2036 --------------------
2037 -- Find_Primitive --
2038 --------------------
2040 function Find_Primitive
(Typ
: Entity_Id
) return Entity_Id
is
2041 procedure Replace_Parameter_Types
(Spec
: Node_Id
);
2042 -- Given a specification Spec, replace all class-wide parameter
2043 -- types with reference to type Typ.
2045 -----------------------------
2046 -- Replace_Parameter_Types --
2047 -----------------------------
2049 procedure Replace_Parameter_Types
(Spec
: Node_Id
) is
2051 Formal_Id
: Entity_Id
;
2052 Formal_Typ
: Node_Id
;
2055 Formal
:= First
(Parameter_Specifications
(Spec
));
2056 while Present
(Formal
) loop
2057 Formal_Id
:= Defining_Identifier
(Formal
);
2058 Formal_Typ
:= Parameter_Type
(Formal
);
2060 -- Create a new entity for each class-wide formal to prevent
2061 -- aliasing with the original renaming. Replace the type of
2062 -- such a parameter with the candidate type.
2064 if Nkind
(Formal_Typ
) = N_Identifier
2065 and then Is_Class_Wide_Type
(Etype
(Formal_Typ
))
2067 Set_Defining_Identifier
(Formal
,
2068 Make_Defining_Identifier
(Loc
, Chars
(Formal_Id
)));
2070 Set_Parameter_Type
(Formal
, New_Occurrence_Of
(Typ
, Loc
));
2075 end Replace_Parameter_Types
;
2079 Alt_Ren
: constant Node_Id
:= New_Copy_Tree
(N
);
2080 Alt_Nam
: constant Node_Id
:= Name
(Alt_Ren
);
2081 Alt_Spec
: constant Node_Id
:= Specification
(Alt_Ren
);
2082 Subp_Id
: Entity_Id
;
2084 -- Start of processing for Find_Primitive
2087 -- Each attempt to find a suitable primitive of a particular type
2088 -- operates on its own copy of the original renaming. As a result
2089 -- the original renaming is kept decoration and side-effect free.
2091 -- Inherit the overloaded status of the renamed subprogram name
2093 if Is_Overloaded
(Nam
) then
2094 Set_Is_Overloaded
(Alt_Nam
);
2095 Save_Interps
(Nam
, Alt_Nam
);
2098 -- The copied renaming is hidden from visibility to prevent the
2099 -- pollution of the enclosing context.
2101 Set_Defining_Unit_Name
(Alt_Spec
, Make_Temporary
(Loc
, 'R'));
2103 -- The types of all class-wide parameters must be changed to the
2106 Replace_Parameter_Types
(Alt_Spec
);
2108 -- Try to find a suitable primitive which matches the altered
2109 -- profile of the renaming specification.
2114 Nam
=> Name
(Alt_Ren
),
2115 New_S
=> Analyze_Subprogram_Specification
(Alt_Spec
),
2116 Is_Actual
=> Is_Actual
);
2118 -- Do not return Any_Id if the resolion of the altered profile
2119 -- failed as this complicates further checks on the caller side,
2120 -- return Empty instead.
2122 if Subp_Id
= Any_Id
then
2129 --------------------------
2130 -- Interpretation_Error --
2131 --------------------------
2133 procedure Interpretation_Error
(Subp_Id
: Entity_Id
) is
2135 Error_Msg_Sloc
:= Sloc
(Subp_Id
);
2137 if Is_Internal
(Subp_Id
) then
2139 ("\\possible interpretation: predefined & #",
2143 ("\\possible interpretation: & defined #", Spec
, Formal_Spec
);
2145 end Interpretation_Error
;
2147 ---------------------------
2148 -- Is_Intrinsic_Equality --
2149 ---------------------------
2151 function Is_Intrinsic_Equality
(Subp_Id
: Entity_Id
) return Boolean is
2154 Ekind
(Subp_Id
) = E_Operator
2155 and then Chars
(Subp_Id
) = Name_Op_Eq
2156 and then Is_Intrinsic_Subprogram
(Subp_Id
);
2157 end Is_Intrinsic_Equality
;
2159 ---------------------------
2160 -- Is_Suitable_Candidate --
2161 ---------------------------
2163 function Is_Suitable_Candidate
(Subp_Id
: Entity_Id
) return Boolean is
2165 if No
(Subp_Id
) then
2168 -- An intrinsic subprogram is never a good candidate. This is an
2169 -- indication of a missing primitive, either defined directly or
2170 -- inherited from a parent tagged type.
2172 elsif Is_Intrinsic_Subprogram
(Subp_Id
) then
2178 end Is_Suitable_Candidate
;
2182 Actual_Typ
: Entity_Id
:= Empty
;
2183 -- The actual class-wide type for Formal_Typ
2185 CW_Prim_OK
: Boolean;
2186 CW_Prim_Op
: Entity_Id
;
2187 -- The class-wide subprogram (if available) which corresponds to the
2188 -- renamed generic formal subprogram.
2190 Formal_Typ
: Entity_Id
:= Empty
;
2191 -- The generic formal type with unknown discriminants
2193 Root_Prim_OK
: Boolean;
2194 Root_Prim_Op
: Entity_Id
;
2195 -- The root type primitive (if available) which corresponds to the
2196 -- renamed generic formal subprogram.
2198 Root_Typ
: Entity_Id
:= Empty
;
2199 -- The root type of Actual_Typ
2201 Body_Decl
: Node_Id
;
2203 Prim_Op
: Entity_Id
;
2204 Spec_Decl
: Node_Id
;
2206 -- Start of processing for Build_Class_Wide_Wrapper
2209 -- Analyze the specification of the renaming in case the generation
2210 -- of the class-wide wrapper fails.
2212 Ren_Id
:= Analyze_Subprogram_Specification
(Spec
);
2215 -- Do not attempt to build a wrapper if the renaming is in error
2217 if Error_Posted
(Nam
) then
2221 -- Analyze the renamed name, but do not resolve it. The resolution is
2222 -- completed once a suitable subprogram is found.
2226 -- When the renamed name denotes the intrinsic operator equals, the
2227 -- name must be treated as overloaded. This allows for a potential
2228 -- match against the root type's predefined equality function.
2230 if Is_Intrinsic_Equality
(Entity
(Nam
)) then
2231 Set_Is_Overloaded
(Nam
);
2232 Collect_Interps
(Nam
);
2235 -- Step 1: Find the generic formal type with unknown discriminants
2236 -- and its corresponding class-wide actual type from the renamed
2237 -- generic formal subprogram.
2239 Formal
:= First_Formal
(Formal_Spec
);
2240 while Present
(Formal
) loop
2241 if Has_Unknown_Discriminants
(Etype
(Formal
))
2242 and then not Is_Class_Wide_Type
(Etype
(Formal
))
2243 and then Is_Class_Wide_Type
(Get_Instance_Of
(Etype
(Formal
)))
2245 Formal_Typ
:= Etype
(Formal
);
2246 Actual_Typ
:= Get_Instance_Of
(Formal_Typ
);
2247 Root_Typ
:= Etype
(Actual_Typ
);
2251 Next_Formal
(Formal
);
2254 -- The specification of the generic formal subprogram should always
2255 -- contain a formal type with unknown discriminants whose actual is
2256 -- a class-wide type, otherwise this indicates a failure in routine
2257 -- Has_Class_Wide_Actual.
2259 pragma Assert
(Present
(Formal_Typ
));
2261 -- Step 2: Find the proper class-wide subprogram or primitive which
2262 -- corresponds to the renamed generic formal subprogram.
2264 CW_Prim_Op
:= Find_Primitive
(Actual_Typ
);
2265 CW_Prim_OK
:= Is_Suitable_Candidate
(CW_Prim_Op
);
2266 Root_Prim_Op
:= Find_Primitive
(Root_Typ
);
2267 Root_Prim_OK
:= Is_Suitable_Candidate
(Root_Prim_Op
);
2269 -- The class-wide actual type has two subprograms which correspond to
2270 -- the renamed generic formal subprogram:
2272 -- with procedure Prim_Op (Param : Formal_Typ);
2274 -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited
2275 -- procedure Prim_Op (Param : Actual_Typ'Class);
2277 -- Even though the declaration of the two subprograms is legal, a
2278 -- call to either one is ambiguous and therefore illegal.
2280 if CW_Prim_OK
and Root_Prim_OK
then
2282 -- A user-defined primitive has precedence over a predefined one
2284 if Is_Internal
(CW_Prim_Op
)
2285 and then not Is_Internal
(Root_Prim_Op
)
2287 Prim_Op
:= Root_Prim_Op
;
2289 elsif Is_Internal
(Root_Prim_Op
)
2290 and then not Is_Internal
(CW_Prim_Op
)
2292 Prim_Op
:= CW_Prim_Op
;
2294 elsif CW_Prim_Op
= Root_Prim_Op
then
2295 Prim_Op
:= Root_Prim_Op
;
2297 -- Otherwise both candidate subprograms are user-defined and
2302 ("ambiguous actual for generic subprogram &",
2304 Interpretation_Error
(Root_Prim_Op
);
2305 Interpretation_Error
(CW_Prim_Op
);
2309 elsif CW_Prim_OK
and not Root_Prim_OK
then
2310 Prim_Op
:= CW_Prim_Op
;
2312 elsif not CW_Prim_OK
and Root_Prim_OK
then
2313 Prim_Op
:= Root_Prim_Op
;
2315 -- An intrinsic equality may act as a suitable candidate in the case
2316 -- of a null type extension where the parent's equality is hidden. A
2317 -- call to an intrinsic equality is expanded as dispatching.
2319 elsif Present
(Root_Prim_Op
)
2320 and then Is_Intrinsic_Equality
(Root_Prim_Op
)
2322 Prim_Op
:= Root_Prim_Op
;
2324 -- Otherwise there are no candidate subprograms. Let the caller
2325 -- diagnose the error.
2331 -- At this point resolution has taken place and the name is no longer
2332 -- overloaded. Mark the primitive as referenced.
2334 Set_Is_Overloaded
(Name
(N
), False);
2335 Set_Referenced
(Prim_Op
);
2337 -- Step 3: Create the declaration and the body of the wrapper, insert
2338 -- all the pieces into the tree.
2341 Make_Subprogram_Declaration
(Loc
,
2342 Specification
=> Build_Spec
(Ren_Id
));
2343 Insert_Before_And_Analyze
(N
, Spec_Decl
);
2345 -- If the operator carries an Eliminated pragma, indicate that the
2346 -- wrapper is also to be eliminated, to prevent spurious error when
2347 -- using gnatelim on programs that include box-initialization of
2348 -- equality operators.
2350 Wrap_Id
:= Defining_Entity
(Spec_Decl
);
2351 Set_Is_Eliminated
(Wrap_Id
, Is_Eliminated
(Prim_Op
));
2354 Make_Subprogram_Body
(Loc
,
2355 Specification
=> Build_Spec
(Ren_Id
),
2356 Declarations
=> New_List
,
2357 Handled_Statement_Sequence
=>
2358 Make_Handled_Sequence_Of_Statements
(Loc
,
2359 Statements
=> New_List
(
2361 (Subp_Id
=> Prim_Op
,
2363 Parameter_Specifications
2364 (Specification
(Spec_Decl
))))));
2366 -- The generated body does not freeze and must be analyzed when the
2367 -- class-wide wrapper is frozen. The body is only needed if expansion
2370 if Expander_Active
then
2371 Append_Freeze_Action
(Wrap_Id
, Body_Decl
);
2374 -- Step 4: The subprogram renaming aliases the wrapper
2376 Rewrite
(Nam
, New_Occurrence_Of
(Wrap_Id
, Loc
));
2377 end Build_Class_Wide_Wrapper
;
2379 --------------------------
2380 -- Check_Null_Exclusion --
2381 --------------------------
2383 procedure Check_Null_Exclusion
2387 Ren_Formal
: Entity_Id
;
2388 Sub_Formal
: Entity_Id
;
2393 Ren_Formal
:= First_Formal
(Ren
);
2394 Sub_Formal
:= First_Formal
(Sub
);
2395 while Present
(Ren_Formal
) and then Present
(Sub_Formal
) loop
2396 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
2398 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
2399 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
2402 ("`NOT NULL` required for parameter &",
2403 Parent
(Sub_Formal
), Sub_Formal
);
2406 Next_Formal
(Ren_Formal
);
2407 Next_Formal
(Sub_Formal
);
2410 -- Return profile check
2412 if Nkind
(Parent
(Ren
)) = N_Function_Specification
2413 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
2414 and then Has_Null_Exclusion
(Parent
(Ren
))
2415 and then not (Has_Null_Exclusion
(Parent
(Sub
))
2416 or else Can_Never_Be_Null
(Etype
(Sub
)))
2419 ("return must specify `NOT NULL`",
2420 Result_Definition
(Parent
(Sub
)));
2422 end Check_Null_Exclusion
;
2424 ---------------------------
2425 -- Freeze_Actual_Profile --
2426 ---------------------------
2428 procedure Freeze_Actual_Profile
is
2430 Has_Untagged_Inc
: Boolean;
2431 Instantiation_Node
: constant Node_Id
:= Parent
(N
);
2434 if Ada_Version
>= Ada_2012
then
2435 F
:= First_Formal
(Formal_Spec
);
2436 Has_Untagged_Inc
:= False;
2437 while Present
(F
) loop
2438 if Ekind
(Etype
(F
)) = E_Incomplete_Type
2439 and then not Is_Tagged_Type
(Etype
(F
))
2441 Has_Untagged_Inc
:= True;
2445 F
:= Next_Formal
(F
);
2448 if Ekind
(Formal_Spec
) = E_Function
2449 and then not Is_Tagged_Type
(Etype
(Formal_Spec
))
2451 Has_Untagged_Inc
:= True;
2454 if not Has_Untagged_Inc
then
2455 F
:= First_Formal
(Old_S
);
2456 while Present
(F
) loop
2457 Freeze_Before
(Instantiation_Node
, Etype
(F
));
2459 if Is_Incomplete_Or_Private_Type
(Etype
(F
))
2460 and then No
(Underlying_Type
(Etype
(F
)))
2462 -- Exclude generic types, or types derived from them.
2463 -- They will be frozen in the enclosing instance.
2465 if Is_Generic_Type
(Etype
(F
))
2466 or else Is_Generic_Type
(Root_Type
(Etype
(F
)))
2470 -- A limited view of a type declared elsewhere needs no
2471 -- freezing actions.
2473 elsif From_Limited_With
(Etype
(F
)) then
2478 ("type& must be frozen before this point",
2479 Instantiation_Node
, Etype
(F
));
2483 F
:= Next_Formal
(F
);
2487 end Freeze_Actual_Profile
;
2489 ---------------------------
2490 -- Has_Class_Wide_Actual --
2491 ---------------------------
2493 function Has_Class_Wide_Actual
return Boolean is
2495 Formal_Typ
: Entity_Id
;
2499 Formal
:= First_Formal
(Formal_Spec
);
2500 while Present
(Formal
) loop
2501 Formal_Typ
:= Etype
(Formal
);
2503 if Has_Unknown_Discriminants
(Formal_Typ
)
2504 and then not Is_Class_Wide_Type
(Formal_Typ
)
2505 and then Is_Class_Wide_Type
(Get_Instance_Of
(Formal_Typ
))
2510 Next_Formal
(Formal
);
2515 end Has_Class_Wide_Actual
;
2517 -------------------------
2518 -- Original_Subprogram --
2519 -------------------------
2521 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
2522 Orig_Decl
: Node_Id
;
2523 Orig_Subp
: Entity_Id
;
2526 -- First case: renamed entity is itself a renaming
2528 if Present
(Alias
(Subp
)) then
2529 return Alias
(Subp
);
2531 elsif Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
2532 and then Present
(Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
2534 -- Check if renamed entity is a renaming_as_body
2537 Unit_Declaration_Node
2538 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
2540 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
2541 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
2543 if Orig_Subp
= Rename_Spec
then
2545 -- Circularity detected
2550 return (Original_Subprogram
(Orig_Subp
));
2558 end Original_Subprogram
;
2562 CW_Actual
: constant Boolean := Has_Class_Wide_Actual
;
2563 -- Ada 2012 (AI05-071, AI05-0131): True if the renaming is for a
2564 -- defaulted formal subprogram when the actual for a related formal
2565 -- type is class-wide.
2567 Inst_Node
: Node_Id
:= Empty
;
2570 -- Start of processing for Analyze_Subprogram_Renaming
2573 -- We must test for the attribute renaming case before the Analyze
2574 -- call because otherwise Sem_Attr will complain that the attribute
2575 -- is missing an argument when it is analyzed.
2577 if Nkind
(Nam
) = N_Attribute_Reference
then
2579 -- In the case of an abstract formal subprogram association, rewrite
2580 -- an actual given by a stream attribute as the name of the
2581 -- corresponding stream primitive of the type.
2583 -- In a generic context the stream operations are not generated, and
2584 -- this must be treated as a normal attribute reference, to be
2585 -- expanded in subsequent instantiations.
2588 and then Is_Abstract_Subprogram
(Formal_Spec
)
2589 and then Expander_Active
2592 Stream_Prim
: Entity_Id
;
2593 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
2596 -- The class-wide forms of the stream attributes are not
2597 -- primitive dispatching operations (even though they
2598 -- internally dispatch to a stream attribute).
2600 if Is_Class_Wide_Type
(Prefix_Type
) then
2602 ("attribute must be a primitive dispatching operation",
2607 -- Retrieve the primitive subprogram associated with the
2608 -- attribute. This can only be a stream attribute, since those
2609 -- are the only ones that are dispatching (and the actual for
2610 -- an abstract formal subprogram must be dispatching
2613 case Attribute_Name
(Nam
) is
2616 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
2619 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
2622 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
2625 Find_Optional_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
2628 ("attribute must be a primitive"
2629 & " dispatching operation", Nam
);
2633 -- If no operation was found, and the type is limited,
2634 -- the user should have defined one.
2636 if No
(Stream_Prim
) then
2637 if Is_Limited_Type
(Prefix_Type
) then
2639 ("stream operation not defined for type&",
2643 -- Otherwise, compiler should have generated default
2646 raise Program_Error
;
2650 -- Rewrite the attribute into the name of its corresponding
2651 -- primitive dispatching subprogram. We can then proceed with
2652 -- the usual processing for subprogram renamings.
2655 Prim_Name
: constant Node_Id
:=
2656 Make_Identifier
(Sloc
(Nam
),
2657 Chars
=> Chars
(Stream_Prim
));
2659 Set_Entity
(Prim_Name
, Stream_Prim
);
2660 Rewrite
(Nam
, Prim_Name
);
2665 -- Normal processing for a renaming of an attribute
2668 Attribute_Renaming
(N
);
2673 -- Check whether this declaration corresponds to the instantiation
2674 -- of a formal subprogram.
2676 -- If this is an instantiation, the corresponding actual is frozen and
2677 -- error messages can be made more precise. If this is a default
2678 -- subprogram, the entity is already established in the generic, and is
2679 -- not retrieved by visibility. If it is a default with a box, the
2680 -- candidate interpretations, if any, have been collected when building
2681 -- the renaming declaration. If overloaded, the proper interpretation is
2682 -- determined in Find_Renamed_Entity. If the entity is an operator,
2683 -- Find_Renamed_Entity applies additional visibility checks.
2686 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
2688 -- Check whether the renaming is for a defaulted actual subprogram
2689 -- with a class-wide actual.
2691 -- The class-wide wrapper is not needed in GNATprove_Mode and there
2692 -- is an external axiomatization on the package.
2695 and then Box_Present
(Inst_Node
)
2699 Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
)))
2701 Build_Class_Wide_Wrapper
(New_S
, Old_S
);
2703 elsif Is_Entity_Name
(Nam
)
2704 and then Present
(Entity
(Nam
))
2705 and then not Comes_From_Source
(Nam
)
2706 and then not Is_Overloaded
(Nam
)
2708 Old_S
:= Entity
(Nam
);
2709 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2713 if Ekind
(Entity
(Nam
)) = E_Operator
then
2717 if Box_Present
(Inst_Node
) then
2718 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
2720 -- If there is an immediately visible homonym of the operator
2721 -- and the declaration has a default, this is worth a warning
2722 -- because the user probably did not intend to get the pre-
2723 -- defined operator, visible in the generic declaration. To
2724 -- find if there is an intended candidate, analyze the renaming
2725 -- again in the current context.
2727 elsif Scope
(Old_S
) = Standard_Standard
2728 and then Present
(Default_Name
(Inst_Node
))
2731 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
2735 Set_Entity
(Name
(Decl
), Empty
);
2736 Analyze
(Name
(Decl
));
2738 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
2741 and then In_Open_Scopes
(Scope
(Hidden
))
2742 and then Is_Immediately_Visible
(Hidden
)
2743 and then Comes_From_Source
(Hidden
)
2744 and then Hidden
/= Old_S
2746 Error_Msg_Sloc
:= Sloc
(Hidden
);
2747 Error_Msg_N
("default subprogram is resolved " &
2748 "in the generic declaration " &
2749 "(RM 12.6(17))??", N
);
2750 Error_Msg_NE
("\and will not use & #??", N
, Hidden
);
2758 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2762 -- Renamed entity must be analyzed first, to avoid being hidden by
2763 -- new name (which might be the same in a generic instance).
2767 -- The renaming defines a new overloaded entity, which is analyzed
2768 -- like a subprogram declaration.
2770 New_S
:= Analyze_Subprogram_Specification
(Spec
);
2773 if Current_Scope
/= Standard_Standard
then
2774 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
2777 -- Set SPARK mode from current context
2779 Set_SPARK_Pragma
(New_S
, SPARK_Mode_Pragma
);
2780 Set_SPARK_Pragma_Inherited
(New_S
);
2782 Rename_Spec
:= Find_Corresponding_Spec
(N
);
2784 -- Case of Renaming_As_Body
2786 if Present
(Rename_Spec
) then
2788 -- Renaming declaration is the completion of the declaration of
2789 -- Rename_Spec. We build an actual body for it at the freezing point.
2791 Set_Corresponding_Spec
(N
, Rename_Spec
);
2793 -- Deal with special case of stream functions of abstract types
2796 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
2797 N_Abstract_Subprogram_Declaration
2799 -- Input stream functions are abstract if the object type is
2800 -- abstract. Similarly, all default stream functions for an
2801 -- interface type are abstract. However, these subprograms may
2802 -- receive explicit declarations in representation clauses, making
2803 -- the attribute subprograms usable as defaults in subsequent
2805 -- In this case we rewrite the declaration to make the subprogram
2806 -- non-abstract. We remove the previous declaration, and insert
2807 -- the new one at the point of the renaming, to prevent premature
2808 -- access to unfrozen types. The new declaration reuses the
2809 -- specification of the previous one, and must not be analyzed.
2812 (Is_Primitive
(Entity
(Nam
))
2814 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
2816 Old_Decl
: constant Node_Id
:=
2817 Unit_Declaration_Node
(Rename_Spec
);
2818 New_Decl
: constant Node_Id
:=
2819 Make_Subprogram_Declaration
(Sloc
(N
),
2821 Relocate_Node
(Specification
(Old_Decl
)));
2824 Insert_After
(N
, New_Decl
);
2825 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
2826 Set_Analyzed
(New_Decl
);
2830 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
2832 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2833 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
2836 Set_Convention
(New_S
, Convention
(Rename_Spec
));
2837 Check_Fully_Conformant
(New_S
, Rename_Spec
);
2838 Set_Public_Status
(New_S
);
2840 -- The specification does not introduce new formals, but only
2841 -- repeats the formals of the original subprogram declaration.
2842 -- For cross-reference purposes, and for refactoring tools, we
2843 -- treat the formals of the renaming declaration as body formals.
2845 Reference_Body_Formals
(Rename_Spec
, New_S
);
2847 -- Indicate that the entity in the declaration functions like the
2848 -- corresponding body, and is not a new entity. The body will be
2849 -- constructed later at the freeze point, so indicate that the
2850 -- completion has not been seen yet.
2852 Set_Ekind
(New_S
, E_Subprogram_Body
);
2853 New_S
:= Rename_Spec
;
2854 Set_Has_Completion
(Rename_Spec
, False);
2856 -- Ada 2005: check overriding indicator
2858 if Present
(Overridden_Operation
(Rename_Spec
)) then
2859 if Must_Not_Override
(Specification
(N
)) then
2861 ("subprogram& overrides inherited operation",
2864 Style_Check
and then not Must_Override
(Specification
(N
))
2866 Style
.Missing_Overriding
(N
, Rename_Spec
);
2869 elsif Must_Override
(Specification
(N
)) then
2870 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
2873 -- Normal subprogram renaming (not renaming as body)
2876 Generate_Definition
(New_S
);
2877 New_Overloaded_Entity
(New_S
);
2879 if Is_Entity_Name
(Nam
)
2880 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
2884 Check_Delayed_Subprogram
(New_S
);
2888 -- There is no need for elaboration checks on the new entity, which may
2889 -- be called before the next freezing point where the body will appear.
2890 -- Elaboration checks refer to the real entity, not the one created by
2891 -- the renaming declaration.
2893 Set_Kill_Elaboration_Checks
(New_S
, True);
2895 -- If we had a previous error, indicate a completely is present to stop
2896 -- junk cascaded messages, but don't take any further action.
2898 if Etype
(Nam
) = Any_Type
then
2899 Set_Has_Completion
(New_S
);
2902 -- Case where name has the form of a selected component
2904 elsif Nkind
(Nam
) = N_Selected_Component
then
2906 -- A name which has the form A.B can designate an entry of task A, a
2907 -- protected operation of protected object A, or finally a primitive
2908 -- operation of object A. In the later case, A is an object of some
2909 -- tagged type, or an access type that denotes one such. To further
2910 -- distinguish these cases, note that the scope of a task entry or
2911 -- protected operation is type of the prefix.
2913 -- The prefix could be an overloaded function call that returns both
2914 -- kinds of operations. This overloading pathology is left to the
2915 -- dedicated reader ???
2918 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
2926 and then Is_Tagged_Type
(Designated_Type
(T
))))
2927 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
2929 Analyze_Renamed_Primitive_Operation
2930 (N
, New_S
, Present
(Rename_Spec
));
2934 -- Renamed entity is an entry or protected operation. For those
2935 -- cases an explicit body is built (at the point of freezing of
2936 -- this entity) that contains a call to the renamed entity.
2938 -- This is not allowed for renaming as body if the renamed
2939 -- spec is already frozen (see RM 8.5.4(5) for details).
2941 if Present
(Rename_Spec
) and then Is_Frozen
(Rename_Spec
) then
2943 ("renaming-as-body cannot rename entry as subprogram", N
);
2945 ("\since & is already frozen (RM 8.5.4(5))",
2948 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
2955 -- Case where name is an explicit dereference X.all
2957 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
2959 -- Renamed entity is designated by access_to_subprogram expression.
2960 -- Must build body to encapsulate call, as in the entry case.
2962 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
2965 -- Indexed component
2967 elsif Nkind
(Nam
) = N_Indexed_Component
then
2968 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
2971 -- Character literal
2973 elsif Nkind
(Nam
) = N_Character_Literal
then
2974 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
2977 -- Only remaining case is where we have a non-entity name, or a renaming
2978 -- of some other non-overloadable entity.
2980 elsif not Is_Entity_Name
(Nam
)
2981 or else not Is_Overloadable
(Entity
(Nam
))
2983 -- Do not mention the renaming if it comes from an instance
2985 if not Is_Actual
then
2986 Error_Msg_N
("expect valid subprogram name in renaming", N
);
2988 Error_Msg_NE
("no visible subprogram for formal&", N
, Nam
);
2994 -- Find the renamed entity that matches the given specification. Disable
2995 -- Ada_83 because there is no requirement of full conformance between
2996 -- renamed entity and new entity, even though the same circuit is used.
2998 -- This is a bit of an odd case, which introduces a really irregular use
2999 -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do
3002 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
3003 Ada_Version_Pragma
:= Empty
;
3004 Ada_Version_Explicit
:= Ada_Version
;
3007 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
3009 -- The visible operation may be an inherited abstract operation that
3010 -- was overridden in the private part, in which case a call will
3011 -- dispatch to the overriding operation. Use the overriding one in
3012 -- the renaming declaration, to prevent spurious errors below.
3014 if Is_Overloadable
(Old_S
)
3015 and then Is_Abstract_Subprogram
(Old_S
)
3016 and then No
(DTC_Entity
(Old_S
))
3017 and then Present
(Alias
(Old_S
))
3018 and then not Is_Abstract_Subprogram
(Alias
(Old_S
))
3019 and then Present
(Overridden_Operation
(Alias
(Old_S
)))
3021 Old_S
:= Alias
(Old_S
);
3024 -- When the renamed subprogram is overloaded and used as an actual
3025 -- of a generic, its entity is set to the first available homonym.
3026 -- We must first disambiguate the name, then set the proper entity.
3028 if Is_Actual
and then Is_Overloaded
(Nam
) then
3029 Set_Entity
(Nam
, Old_S
);
3033 -- Most common case: subprogram renames subprogram. No body is generated
3034 -- in this case, so we must indicate the declaration is complete as is.
3035 -- and inherit various attributes of the renamed subprogram.
3037 if No
(Rename_Spec
) then
3038 Set_Has_Completion
(New_S
);
3039 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
3040 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
3041 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
3043 -- The subprogram renaming declaration may become Ghost if it renames
3046 Mark_Renaming_As_Ghost
(N
, Entity
(Nam
));
3048 -- Ada 2005 (AI-423): Check the consistency of null exclusions
3049 -- between a subprogram and its correct renaming.
3051 -- Note: the Any_Id check is a guard that prevents compiler crashes
3052 -- when performing a null exclusion check between a renaming and a
3053 -- renamed subprogram that has been found to be illegal.
3055 if Ada_Version
>= Ada_2005
and then Entity
(Nam
) /= Any_Id
then
3056 Check_Null_Exclusion
3058 Sub
=> Entity
(Nam
));
3061 -- Enforce the Ada 2005 rule that the renamed entity cannot require
3062 -- overriding. The flag Requires_Overriding is set very selectively
3063 -- and misses some other illegal cases. The additional conditions
3064 -- checked below are sufficient but not necessary ???
3066 -- The rule does not apply to the renaming generated for an actual
3067 -- subprogram in an instance.
3072 -- Guard against previous errors, and omit renamings of predefined
3075 elsif not Ekind_In
(Old_S
, E_Function
, E_Procedure
) then
3078 elsif Requires_Overriding
(Old_S
)
3080 (Is_Abstract_Subprogram
(Old_S
)
3081 and then Present
(Find_Dispatching_Type
(Old_S
))
3083 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
3086 ("renamed entity cannot be "
3087 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
3091 if Old_S
/= Any_Id
then
3092 if Is_Actual
and then From_Default
(N
) then
3094 -- This is an implicit reference to the default actual
3096 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
3099 Generate_Reference
(Old_S
, Nam
);
3102 Check_Internal_Protected_Use
(N
, Old_S
);
3104 -- For a renaming-as-body, require subtype conformance, but if the
3105 -- declaration being completed has not been frozen, then inherit the
3106 -- convention of the renamed subprogram prior to checking conformance
3107 -- (unless the renaming has an explicit convention established; the
3108 -- rule stated in the RM doesn't seem to address this ???).
3110 if Present
(Rename_Spec
) then
3111 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
3112 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
3114 if not Is_Frozen
(Rename_Spec
) then
3115 if not Has_Convention_Pragma
(Rename_Spec
) then
3116 Set_Convention
(New_S
, Convention
(Old_S
));
3119 if Ekind
(Old_S
) /= E_Operator
then
3120 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
3123 if Original_Subprogram
(Old_S
) = Rename_Spec
then
3124 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
3127 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
3130 Check_Frozen_Renaming
(N
, Rename_Spec
);
3132 -- Check explicitly that renamed entity is not intrinsic, because
3133 -- in a generic the renamed body is not built. In this case,
3134 -- the renaming_as_body is a completion.
3136 if Inside_A_Generic
then
3137 if Is_Frozen
(Rename_Spec
)
3138 and then Is_Intrinsic_Subprogram
(Old_S
)
3141 ("subprogram in renaming_as_body cannot be intrinsic",
3145 Set_Has_Completion
(Rename_Spec
);
3148 elsif Ekind
(Old_S
) /= E_Operator
then
3150 -- If this a defaulted subprogram for a class-wide actual there is
3151 -- no check for mode conformance, given that the signatures don't
3152 -- match (the source mentions T but the actual mentions T'Class).
3156 elsif not Is_Actual
or else No
(Enclosing_Instance
) then
3157 Check_Mode_Conformant
(New_S
, Old_S
);
3160 if Is_Actual
and then Error_Posted
(New_S
) then
3161 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
3165 if No
(Rename_Spec
) then
3167 -- The parameter profile of the new entity is that of the renamed
3168 -- entity: the subtypes given in the specification are irrelevant.
3170 Inherit_Renamed_Profile
(New_S
, Old_S
);
3172 -- A call to the subprogram is transformed into a call to the
3173 -- renamed entity. This is transitive if the renamed entity is
3174 -- itself a renaming.
3176 if Present
(Alias
(Old_S
)) then
3177 Set_Alias
(New_S
, Alias
(Old_S
));
3179 Set_Alias
(New_S
, Old_S
);
3182 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
3183 -- renaming as body, since the entity in this case is not an
3184 -- intrinsic (it calls an intrinsic, but we have a real body for
3185 -- this call, and it is in this body that the required intrinsic
3186 -- processing will take place).
3188 -- Also, if this is a renaming of inequality, the renamed operator
3189 -- is intrinsic, but what matters is the corresponding equality
3190 -- operator, which may be user-defined.
3192 Set_Is_Intrinsic_Subprogram
3194 Is_Intrinsic_Subprogram
(Old_S
)
3196 (Chars
(Old_S
) /= Name_Op_Ne
3197 or else Ekind
(Old_S
) = E_Operator
3198 or else Is_Intrinsic_Subprogram
3199 (Corresponding_Equality
(Old_S
))));
3201 if Ekind
(Alias
(New_S
)) = E_Operator
then
3202 Set_Has_Delayed_Freeze
(New_S
, False);
3205 -- If the renaming corresponds to an association for an abstract
3206 -- formal subprogram, then various attributes must be set to
3207 -- indicate that the renaming is an abstract dispatching operation
3208 -- with a controlling type.
3210 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
3212 -- Mark the renaming as abstract here, so Find_Dispatching_Type
3213 -- see it as corresponding to a generic association for a
3214 -- formal abstract subprogram
3216 Set_Is_Abstract_Subprogram
(New_S
);
3219 New_S_Ctrl_Type
: constant Entity_Id
:=
3220 Find_Dispatching_Type
(New_S
);
3221 Old_S_Ctrl_Type
: constant Entity_Id
:=
3222 Find_Dispatching_Type
(Old_S
);
3226 -- The actual must match the (instance of the) formal,
3227 -- and must be a controlling type.
3229 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
3230 or else No
(New_S_Ctrl_Type
)
3233 ("actual must be dispatching subprogram for type&",
3234 Nam
, New_S_Ctrl_Type
);
3237 Set_Is_Dispatching_Operation
(New_S
);
3238 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
3240 -- If the actual in the formal subprogram is itself a
3241 -- formal abstract subprogram association, there's no
3242 -- dispatch table component or position to inherit.
3244 if Present
(DTC_Entity
(Old_S
)) then
3245 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
3246 Set_DT_Position_Value
(New_S
, DT_Position
(Old_S
));
3256 -- The following is illegal, because F hides whatever other F may
3258 -- function F (...) renames F;
3261 or else (Nkind
(Nam
) /= N_Expanded_Name
3262 and then Chars
(Old_S
) = Chars
(New_S
))
3264 Error_Msg_N
("subprogram cannot rename itself", N
);
3266 -- This is illegal even if we use a selector:
3267 -- function F (...) renames Pkg.F;
3268 -- because F is still hidden.
3270 elsif Nkind
(Nam
) = N_Expanded_Name
3271 and then Entity
(Prefix
(Nam
)) = Current_Scope
3272 and then Chars
(Selector_Name
(Nam
)) = Chars
(New_S
)
3274 -- This is an error, but we overlook the error and accept the
3275 -- renaming if the special Overriding_Renamings mode is in effect.
3277 if not Overriding_Renamings
then
3279 ("implicit operation& is not visible (RM 8.3 (15))",
3284 Set_Convention
(New_S
, Convention
(Old_S
));
3286 if Is_Abstract_Subprogram
(Old_S
) then
3287 if Present
(Rename_Spec
) then
3289 ("a renaming-as-body cannot rename an abstract subprogram",
3291 Set_Has_Completion
(Rename_Spec
);
3293 Set_Is_Abstract_Subprogram
(New_S
);
3297 Check_Library_Unit_Renaming
(N
, Old_S
);
3299 -- Pathological case: procedure renames entry in the scope of its
3300 -- task. Entry is given by simple name, but body must be built for
3301 -- procedure. Of course if called it will deadlock.
3303 if Ekind
(Old_S
) = E_Entry
then
3304 Set_Has_Completion
(New_S
, False);
3305 Set_Alias
(New_S
, Empty
);
3309 Freeze_Before
(N
, Old_S
);
3310 Freeze_Actual_Profile
;
3311 Set_Has_Delayed_Freeze
(New_S
, False);
3312 Freeze_Before
(N
, New_S
);
3314 -- An abstract subprogram is only allowed as an actual in the case
3315 -- where the formal subprogram is also abstract.
3317 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
3318 and then Is_Abstract_Subprogram
(Old_S
)
3319 and then not Is_Abstract_Subprogram
(Formal_Spec
)
3322 ("abstract subprogram not allowed as generic actual", Nam
);
3327 -- A common error is to assume that implicit operators for types are
3328 -- defined in Standard, or in the scope of a subtype. In those cases
3329 -- where the renamed entity is given with an expanded name, it is
3330 -- worth mentioning that operators for the type are not declared in
3331 -- the scope given by the prefix.
3333 if Nkind
(Nam
) = N_Expanded_Name
3334 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
3335 and then Scope
(Entity
(Nam
)) = Standard_Standard
3338 T
: constant Entity_Id
:=
3339 Base_Type
(Etype
(First_Formal
(New_S
)));
3341 Error_Msg_Node_2
:= Prefix
(Nam
);
3343 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
3348 ("no visible subprogram matches the specification for&",
3352 if Present
(Candidate_Renaming
) then
3359 F1
:= First_Formal
(Candidate_Renaming
);
3360 F2
:= First_Formal
(New_S
);
3361 T1
:= First_Subtype
(Etype
(F1
));
3362 while Present
(F1
) and then Present
(F2
) loop
3367 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
3368 if Present
(Next_Formal
(F1
)) then
3370 ("\missing specification for & and other formals with "
3371 & "defaults", Spec
, F1
);
3373 Error_Msg_NE
("\missing specification for &", Spec
, F1
);
3377 if Nkind
(Nam
) = N_Operator_Symbol
3378 and then From_Default
(N
)
3380 Error_Msg_Node_2
:= T1
;
3382 ("default & on & is not directly visible",
3389 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
3390 -- controlling access parameters are known non-null for the renamed
3391 -- subprogram. Test also applies to a subprogram instantiation that
3392 -- is dispatching. Test is skipped if some previous error was detected
3393 -- that set Old_S to Any_Id.
3395 if Ada_Version
>= Ada_2005
3396 and then Old_S
/= Any_Id
3397 and then not Is_Dispatching_Operation
(Old_S
)
3398 and then Is_Dispatching_Operation
(New_S
)
3405 Old_F
:= First_Formal
(Old_S
);
3406 New_F
:= First_Formal
(New_S
);
3407 while Present
(Old_F
) loop
3408 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
3409 and then Is_Controlling_Formal
(New_F
)
3410 and then not Can_Never_Be_Null
(Old_F
)
3412 Error_Msg_N
("access parameter is controlling,", New_F
);
3414 ("\corresponding parameter of& "
3415 & "must be explicitly null excluding", New_F
, Old_S
);
3418 Next_Formal
(Old_F
);
3419 Next_Formal
(New_F
);
3424 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
3425 -- is to warn if an operator is being renamed as a different operator.
3426 -- If the operator is predefined, examine the kind of the entity, not
3427 -- the abbreviated declaration in Standard.
3429 if Comes_From_Source
(N
)
3430 and then Present
(Old_S
)
3431 and then (Nkind
(Old_S
) = N_Defining_Operator_Symbol
3432 or else Ekind
(Old_S
) = E_Operator
)
3433 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
3434 and then Chars
(Old_S
) /= Chars
(New_S
)
3437 ("& is being renamed as a different operator??", N
, Old_S
);
3440 -- Check for renaming of obsolescent subprogram
3442 Check_Obsolescent_2005_Entity
(Entity
(Nam
), Nam
);
3444 -- Another warning or some utility: if the new subprogram as the same
3445 -- name as the old one, the old one is not hidden by an outer homograph,
3446 -- the new one is not a public symbol, and the old one is otherwise
3447 -- directly visible, the renaming is superfluous.
3449 if Chars
(Old_S
) = Chars
(New_S
)
3450 and then Comes_From_Source
(N
)
3451 and then Scope
(Old_S
) /= Standard_Standard
3452 and then Warn_On_Redundant_Constructs
3453 and then (Is_Immediately_Visible
(Old_S
)
3454 or else Is_Potentially_Use_Visible
(Old_S
))
3455 and then Is_Overloadable
(Current_Scope
)
3456 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
3459 ("redundant renaming, entity is directly visible?r?", Name
(N
));
3462 -- Implementation-defined aspect specifications can appear in a renaming
3463 -- declaration, but not language-defined ones. The call to procedure
3464 -- Analyze_Aspect_Specifications will take care of this error check.
3466 if Has_Aspects
(N
) then
3467 Analyze_Aspect_Specifications
(N
, New_S
);
3470 Ada_Version
:= Save_AV
;
3471 Ada_Version_Pragma
:= Save_AVP
;
3472 Ada_Version_Explicit
:= Save_AV_Exp
;
3474 -- In GNATprove mode, the renamings of actual subprograms are replaced
3475 -- with wrapper functions that make it easier to propagate axioms to the
3476 -- points of call within an instance. Wrappers are generated if formal
3477 -- subprogram is subject to axiomatization.
3479 -- The types in the wrapper profiles are obtained from (instances of)
3480 -- the types of the formal subprogram.
3483 and then GNATprove_Mode
3484 and then Present
(Containing_Package_With_Ext_Axioms
(Formal_Spec
))
3485 and then not Inside_A_Generic
3487 if Ekind
(Old_S
) = E_Function
then
3488 Rewrite
(N
, Build_Function_Wrapper
(Formal_Spec
, Old_S
));
3491 elsif Ekind
(Old_S
) = E_Operator
then
3492 Rewrite
(N
, Build_Operator_Wrapper
(Formal_Spec
, Old_S
));
3496 end Analyze_Subprogram_Renaming
;
3498 -------------------------
3499 -- Analyze_Use_Package --
3500 -------------------------
3502 -- Resolve the package names in the use clause, and make all the visible
3503 -- entities defined in the package potentially use-visible. If the package
3504 -- is already in use from a previous use clause, its visible entities are
3505 -- already use-visible. In that case, mark the occurrence as a redundant
3506 -- use. If the package is an open scope, i.e. if the use clause occurs
3507 -- within the package itself, ignore it.
3509 procedure Analyze_Use_Package
(N
: Node_Id
) is
3510 Pack_Name
: Node_Id
;
3513 -- Start of processing for Analyze_Use_Package
3516 Check_SPARK_05_Restriction
("use clause is not allowed", N
);
3518 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3520 -- Use clause not allowed in a spec of a predefined package declaration
3521 -- except that packages whose file name starts a-n are OK (these are
3522 -- children of Ada.Numerics, which are never loaded by Rtsfind).
3524 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3525 and then Name_Buffer
(1 .. 3) /= "a-n"
3527 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
3529 Error_Msg_N
("use clause not allowed in predefined spec", N
);
3532 -- Chain clause to list of use clauses in current scope
3534 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3535 Chain_Use_Clause
(N
);
3538 -- Loop through package names to identify referenced packages
3540 Pack_Name
:= First
(Names
(N
));
3541 while Present
(Pack_Name
) loop
3542 Analyze
(Pack_Name
);
3544 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3545 and then Nkind
(Pack_Name
) = N_Expanded_Name
3551 Pref
:= Prefix
(Pack_Name
);
3552 while Nkind
(Pref
) = N_Expanded_Name
loop
3553 Pref
:= Prefix
(Pref
);
3556 if Entity
(Pref
) = Standard_Standard
then
3558 ("predefined package Standard cannot appear"
3559 & " in a context clause", Pref
);
3567 -- Loop through package names to mark all entities as potentially
3570 Pack_Name
:= First
(Names
(N
));
3571 while Present
(Pack_Name
) loop
3572 if Is_Entity_Name
(Pack_Name
) then
3573 Pack
:= Entity
(Pack_Name
);
3575 if Ekind
(Pack
) /= E_Package
and then Etype
(Pack
) /= Any_Type
then
3576 if Ekind
(Pack
) = E_Generic_Package
then
3577 Error_Msg_N
-- CODEFIX
3578 ("a generic package is not allowed in a use clause",
3581 elsif Ekind_In
(Pack
, E_Generic_Function
, E_Generic_Package
)
3583 Error_Msg_N
-- CODEFIX
3584 ("a generic subprogram is not allowed in a use clause",
3587 elsif Ekind_In
(Pack
, E_Function
, E_Procedure
, E_Operator
) then
3588 Error_Msg_N
-- CODEFIX
3589 ("a subprogram is not allowed in a use clause",
3593 Error_Msg_N
("& is not allowed in a use clause", Pack_Name
);
3597 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3598 Check_In_Previous_With_Clause
(N
, Pack_Name
);
3601 if Applicable_Use
(Pack_Name
) then
3602 Use_One_Package
(Pack
, N
);
3606 -- Report error because name denotes something other than a package
3609 Error_Msg_N
("& is not a package", Pack_Name
);
3614 end Analyze_Use_Package
;
3616 ----------------------
3617 -- Analyze_Use_Type --
3618 ----------------------
3620 procedure Analyze_Use_Type
(N
: Node_Id
) is
3625 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3627 -- Chain clause to list of use clauses in current scope
3629 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
3630 Chain_Use_Clause
(N
);
3633 -- If the Used_Operations list is already initialized, the clause has
3634 -- been analyzed previously, and it is begin reinstalled, for example
3635 -- when the clause appears in a package spec and we are compiling the
3636 -- corresponding package body. In that case, make the entities on the
3637 -- existing list use_visible, and mark the corresponding types In_Use.
3639 if Present
(Used_Operations
(N
)) then
3645 Mark
:= First
(Subtype_Marks
(N
));
3646 while Present
(Mark
) loop
3647 Use_One_Type
(Mark
, Installed
=> True);
3651 Elmt
:= First_Elmt
(Used_Operations
(N
));
3652 while Present
(Elmt
) loop
3653 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
3661 -- Otherwise, create new list and attach to it the operations that
3662 -- are made use-visible by the clause.
3664 Set_Used_Operations
(N
, New_Elmt_List
);
3665 Id
:= First
(Subtype_Marks
(N
));
3666 while Present
(Id
) loop
3670 if E
/= Any_Type
then
3673 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
3674 if Nkind
(Id
) = N_Identifier
then
3675 Error_Msg_N
("type is not directly visible", Id
);
3677 elsif Is_Child_Unit
(Scope
(E
))
3678 and then Scope
(E
) /= System_Aux_Id
3680 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
3685 -- If the use_type_clause appears in a compilation unit context,
3686 -- check whether it comes from a unit that may appear in a
3687 -- limited_with_clause, for a better error message.
3689 if Nkind
(Parent
(N
)) = N_Compilation_Unit
3690 and then Nkind
(Id
) /= N_Identifier
3696 function Mentioned
(Nam
: Node_Id
) return Boolean;
3697 -- Check whether the prefix of expanded name for the type
3698 -- appears in the prefix of some limited_with_clause.
3704 function Mentioned
(Nam
: Node_Id
) return Boolean is
3706 return Nkind
(Name
(Item
)) = N_Selected_Component
3707 and then Chars
(Prefix
(Name
(Item
))) = Chars
(Nam
);
3711 Pref
:= Prefix
(Id
);
3712 Item
:= First
(Context_Items
(Parent
(N
)));
3713 while Present
(Item
) and then Item
/= N
loop
3714 if Nkind
(Item
) = N_With_Clause
3715 and then Limited_Present
(Item
)
3716 and then Mentioned
(Pref
)
3719 (Get_Msg_Id
, "premature usage of incomplete type");
3730 end Analyze_Use_Type
;
3732 --------------------
3733 -- Applicable_Use --
3734 --------------------
3736 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
3737 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
3740 if In_Open_Scopes
(Pack
) then
3741 if Warn_On_Redundant_Constructs
and then Pack
= Current_Scope
then
3742 Error_Msg_NE
-- CODEFIX
3743 ("& is already use-visible within itself?r?", Pack_Name
, Pack
);
3748 elsif In_Use
(Pack
) then
3749 Note_Redundant_Use
(Pack_Name
);
3752 elsif Present
(Renamed_Object
(Pack
))
3753 and then In_Use
(Renamed_Object
(Pack
))
3755 Note_Redundant_Use
(Pack_Name
);
3763 ------------------------
3764 -- Attribute_Renaming --
3765 ------------------------
3767 procedure Attribute_Renaming
(N
: Node_Id
) is
3768 Loc
: constant Source_Ptr
:= Sloc
(N
);
3769 Nam
: constant Node_Id
:= Name
(N
);
3770 Spec
: constant Node_Id
:= Specification
(N
);
3771 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
3772 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
3774 Form_Num
: Nat
:= 0;
3775 Expr_List
: List_Id
:= No_List
;
3777 Attr_Node
: Node_Id
;
3778 Body_Node
: Node_Id
;
3779 Param_Spec
: Node_Id
;
3782 Generate_Definition
(New_S
);
3784 -- This procedure is called in the context of subprogram renaming, and
3785 -- thus the attribute must be one that is a subprogram. All of those
3786 -- have at least one formal parameter, with the exceptions of the GNAT
3787 -- attribute 'Img, which GNAT treats as renameable.
3789 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
3790 if Aname
/= Name_Img
then
3792 ("subprogram renaming an attribute must have formals", N
);
3797 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
3798 while Present
(Param_Spec
) loop
3799 Form_Num
:= Form_Num
+ 1;
3801 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
3802 Find_Type
(Parameter_Type
(Param_Spec
));
3804 -- The profile of the new entity denotes the base type (s) of
3805 -- the types given in the specification. For access parameters
3806 -- there are no subtypes involved.
3808 Rewrite
(Parameter_Type
(Param_Spec
),
3810 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
3813 if No
(Expr_List
) then
3814 Expr_List
:= New_List
;
3817 Append_To
(Expr_List
,
3818 Make_Identifier
(Loc
,
3819 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
3821 -- The expressions in the attribute reference are not freeze
3822 -- points. Neither is the attribute as a whole, see below.
3824 Set_Must_Not_Freeze
(Last
(Expr_List
));
3829 -- Immediate error if too many formals. Other mismatches in number or
3830 -- types of parameters are detected when we analyze the body of the
3831 -- subprogram that we construct.
3833 if Form_Num
> 2 then
3834 Error_Msg_N
("too many formals for attribute", N
);
3836 -- Error if the attribute reference has expressions that look like
3837 -- formal parameters.
3839 elsif Present
(Expressions
(Nam
)) then
3840 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
3843 Nam_In
(Aname
, Name_Compose
, Name_Exponent
, Name_Leading_Part
,
3844 Name_Pos
, Name_Round
, Name_Scaling
,
3847 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
3848 and then Present
(Corresponding_Formal_Spec
(N
))
3851 ("generic actual cannot be attribute involving universal type",
3855 ("attribute involving a universal type cannot be renamed",
3860 -- Rewrite attribute node to have a list of expressions corresponding to
3861 -- the subprogram formals. A renaming declaration is not a freeze point,
3862 -- and the analysis of the attribute reference should not freeze the
3863 -- type of the prefix. We use the original node in the renaming so that
3864 -- its source location is preserved, and checks on stream attributes are
3865 -- properly applied.
3867 Attr_Node
:= Relocate_Node
(Nam
);
3868 Set_Expressions
(Attr_Node
, Expr_List
);
3870 Set_Must_Not_Freeze
(Attr_Node
);
3871 Set_Must_Not_Freeze
(Prefix
(Nam
));
3873 -- Case of renaming a function
3875 if Nkind
(Spec
) = N_Function_Specification
then
3876 if Is_Procedure_Attribute_Name
(Aname
) then
3877 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
3881 Find_Type
(Result_Definition
(Spec
));
3882 Rewrite
(Result_Definition
(Spec
),
3884 (Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
3887 Make_Subprogram_Body
(Loc
,
3888 Specification
=> Spec
,
3889 Declarations
=> New_List
,
3890 Handled_Statement_Sequence
=>
3891 Make_Handled_Sequence_Of_Statements
(Loc
,
3892 Statements
=> New_List
(
3893 Make_Simple_Return_Statement
(Loc
,
3894 Expression
=> Attr_Node
))));
3896 -- Case of renaming a procedure
3899 if not Is_Procedure_Attribute_Name
(Aname
) then
3900 Error_Msg_N
("attribute can only be renamed as function", Nam
);
3905 Make_Subprogram_Body
(Loc
,
3906 Specification
=> Spec
,
3907 Declarations
=> New_List
,
3908 Handled_Statement_Sequence
=>
3909 Make_Handled_Sequence_Of_Statements
(Loc
,
3910 Statements
=> New_List
(Attr_Node
)));
3913 -- In case of tagged types we add the body of the generated function to
3914 -- the freezing actions of the type (because in the general case such
3915 -- type is still not frozen). We exclude from this processing generic
3916 -- formal subprograms found in instantiations.
3918 -- We must exclude restricted run-time libraries because
3919 -- entity AST_Handler is defined in package System.Aux_Dec which is not
3920 -- available in those platforms. Note that we cannot use the function
3921 -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because
3922 -- the ZFP run-time library is not defined as a profile, and we do not
3923 -- want to deal with AST_Handler in ZFP mode.
3925 if not Configurable_Run_Time_Mode
3926 and then not Present
(Corresponding_Formal_Spec
(N
))
3927 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
3930 P
: constant Node_Id
:= Prefix
(Nam
);
3933 -- The prefix of 'Img is an object that is evaluated for each call
3934 -- of the function that renames it.
3936 if Aname
= Name_Img
then
3937 Preanalyze_And_Resolve
(P
);
3939 -- For all other attribute renamings, the prefix is a subtype
3945 -- If the target type is not yet frozen, add the body to the
3946 -- actions to be elaborated at freeze time.
3948 if Is_Tagged_Type
(Etype
(P
))
3949 and then In_Open_Scopes
(Scope
(Etype
(P
)))
3951 Ensure_Freeze_Node
(Etype
(P
));
3952 Append_Freeze_Action
(Etype
(P
), Body_Node
);
3954 Rewrite
(N
, Body_Node
);
3956 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3960 -- Generic formal subprograms or AST_Handler renaming
3963 Rewrite
(N
, Body_Node
);
3965 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
3968 if Is_Compilation_Unit
(New_S
) then
3970 ("a library unit can only rename another library unit", N
);
3973 -- We suppress elaboration warnings for the resulting entity, since
3974 -- clearly they are not needed, and more particularly, in the case
3975 -- of a generic formal subprogram, the resulting entity can appear
3976 -- after the instantiation itself, and thus look like a bogus case
3977 -- of access before elaboration.
3979 Set_Suppress_Elaboration_Warnings
(New_S
);
3981 end Attribute_Renaming
;
3983 ----------------------
3984 -- Chain_Use_Clause --
3985 ----------------------
3987 procedure Chain_Use_Clause
(N
: Node_Id
) is
3989 Level
: Int
:= Scope_Stack
.Last
;
3992 if not Is_Compilation_Unit
(Current_Scope
)
3993 or else not Is_Child_Unit
(Current_Scope
)
3995 null; -- Common case
3997 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
3998 null; -- Common case for compilation unit
4001 -- If declaration appears in some other scope, it must be in some
4002 -- parent unit when compiling a child.
4004 Pack
:= Defining_Entity
(Parent
(N
));
4005 if not In_Open_Scopes
(Pack
) then
4006 null; -- default as well
4008 -- If the use clause appears in an ancestor and we are in the
4009 -- private part of the immediate parent, the use clauses are
4010 -- already installed.
4012 elsif Pack
/= Scope
(Current_Scope
)
4013 and then In_Private_Part
(Scope
(Current_Scope
))
4018 -- Find entry for parent unit in scope stack
4020 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
4026 Set_Next_Use_Clause
(N
,
4027 Scope_Stack
.Table
(Level
).First_Use_Clause
);
4028 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
4029 end Chain_Use_Clause
;
4031 ---------------------------
4032 -- Check_Frozen_Renaming --
4033 ---------------------------
4035 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
4040 if Is_Frozen
(Subp
) and then not Has_Completion
(Subp
) then
4043 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
4045 if Is_Entity_Name
(Name
(N
)) then
4046 Old_S
:= Entity
(Name
(N
));
4048 if not Is_Frozen
(Old_S
)
4049 and then Operating_Mode
/= Check_Semantics
4051 Append_Freeze_Action
(Old_S
, B_Node
);
4053 Insert_After
(N
, B_Node
);
4057 if Is_Intrinsic_Subprogram
(Old_S
) and then not In_Instance
then
4059 ("subprogram used in renaming_as_body cannot be intrinsic",
4064 Insert_After
(N
, B_Node
);
4068 end Check_Frozen_Renaming
;
4070 -------------------------------
4071 -- Set_Entity_Or_Discriminal --
4072 -------------------------------
4074 procedure Set_Entity_Or_Discriminal
(N
: Node_Id
; E
: Entity_Id
) is
4078 -- If the entity is not a discriminant, or else expansion is disabled,
4079 -- simply set the entity.
4081 if not In_Spec_Expression
4082 or else Ekind
(E
) /= E_Discriminant
4083 or else Inside_A_Generic
4085 Set_Entity_With_Checks
(N
, E
);
4087 -- The replacement of a discriminant by the corresponding discriminal
4088 -- is not done for a task discriminant that appears in a default
4089 -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant
4090 -- for details on their handling.
4092 elsif Is_Concurrent_Type
(Scope
(E
)) then
4095 and then not Nkind_In
(P
, N_Parameter_Specification
,
4096 N_Component_Declaration
)
4102 and then Nkind
(P
) = N_Parameter_Specification
4107 Set_Entity
(N
, Discriminal
(E
));
4110 -- Otherwise, this is a discriminant in a context in which
4111 -- it is a reference to the corresponding parameter of the
4112 -- init proc for the enclosing type.
4115 Set_Entity
(N
, Discriminal
(E
));
4117 end Set_Entity_Or_Discriminal
;
4119 -----------------------------------
4120 -- Check_In_Previous_With_Clause --
4121 -----------------------------------
4123 procedure Check_In_Previous_With_Clause
4127 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
4132 Item
:= First
(Context_Items
(Parent
(N
)));
4133 while Present
(Item
) and then Item
/= N
loop
4134 if Nkind
(Item
) = N_With_Clause
4136 -- Protect the frontend against previous critical errors
4138 and then Nkind
(Name
(Item
)) /= N_Selected_Component
4139 and then Entity
(Name
(Item
)) = Pack
4143 -- Find root library unit in with_clause
4145 while Nkind
(Par
) = N_Expanded_Name
loop
4146 Par
:= Prefix
(Par
);
4149 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
4150 Error_Msg_NE
("& is not directly visible", Par
, Entity
(Par
));
4159 -- On exit, package is not mentioned in a previous with_clause.
4160 -- Check if its prefix is.
4162 if Nkind
(Nam
) = N_Expanded_Name
then
4163 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
4165 elsif Pack
/= Any_Id
then
4166 Error_Msg_NE
("& is not visible", Nam
, Pack
);
4168 end Check_In_Previous_With_Clause
;
4170 ---------------------------------
4171 -- Check_Library_Unit_Renaming --
4172 ---------------------------------
4174 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
4178 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
4181 -- Check for library unit. Note that we used to check for the scope
4182 -- being Standard here, but that was wrong for Standard itself.
4184 elsif not Is_Compilation_Unit
(Old_E
)
4185 and then not Is_Child_Unit
(Old_E
)
4187 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4189 -- Entities defined in Standard (operators and boolean literals) cannot
4190 -- be renamed as library units.
4192 elsif Scope
(Old_E
) = Standard_Standard
4193 and then Sloc
(Old_E
) = Standard_Location
4195 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
4197 elsif Present
(Parent_Spec
(N
))
4198 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
4199 and then not Is_Child_Unit
(Old_E
)
4202 ("renamed unit must be a child unit of generic parent", Name
(N
));
4204 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
4205 and then Nkind
(Name
(N
)) = N_Expanded_Name
4206 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
4207 and then Is_Generic_Unit
(Old_E
)
4210 ("renamed generic unit must be a library unit", Name
(N
));
4212 elsif Is_Package_Or_Generic_Package
(Old_E
) then
4214 -- Inherit categorization flags
4216 New_E
:= Defining_Entity
(N
);
4217 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
4218 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
4219 Set_Is_Remote_Call_Interface
(New_E
,
4220 Is_Remote_Call_Interface
(Old_E
));
4221 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
4222 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
4224 end Check_Library_Unit_Renaming
;
4226 ------------------------
4227 -- Enclosing_Instance --
4228 ------------------------
4230 function Enclosing_Instance
return Entity_Id
is
4234 if not Is_Generic_Instance
(Current_Scope
) then
4238 S
:= Scope
(Current_Scope
);
4239 while S
/= Standard_Standard
loop
4240 if Is_Generic_Instance
(S
) then
4248 end Enclosing_Instance
;
4254 procedure End_Scope
is
4260 Id
:= First_Entity
(Current_Scope
);
4261 while Present
(Id
) loop
4262 -- An entity in the current scope is not necessarily the first one
4263 -- on its homonym chain. Find its predecessor if any,
4264 -- If it is an internal entity, it will not be in the visibility
4265 -- chain altogether, and there is nothing to unchain.
4267 if Id
/= Current_Entity
(Id
) then
4268 Prev
:= Current_Entity
(Id
);
4269 while Present
(Prev
)
4270 and then Present
(Homonym
(Prev
))
4271 and then Homonym
(Prev
) /= Id
4273 Prev
:= Homonym
(Prev
);
4276 -- Skip to end of loop if Id is not in the visibility chain
4278 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
4286 Set_Is_Immediately_Visible
(Id
, False);
4288 Outer
:= Homonym
(Id
);
4289 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
4290 Outer
:= Homonym
(Outer
);
4293 -- Reset homonym link of other entities, but do not modify link
4294 -- between entities in current scope, so that the back-end can have
4295 -- a proper count of local overloadings.
4298 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
4300 elsif Scope
(Prev
) /= Scope
(Id
) then
4301 Set_Homonym
(Prev
, Outer
);
4308 -- If the scope generated freeze actions, place them before the
4309 -- current declaration and analyze them. Type declarations and
4310 -- the bodies of initialization procedures can generate such nodes.
4311 -- We follow the parent chain until we reach a list node, which is
4312 -- the enclosing list of declarations. If the list appears within
4313 -- a protected definition, move freeze nodes outside the protected
4317 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
4321 L
: constant List_Id
:= Scope_Stack
.Table
4322 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
4325 if Is_Itype
(Current_Scope
) then
4326 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
4328 Decl
:= Parent
(Current_Scope
);
4333 while not (Is_List_Member
(Decl
))
4334 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
4337 Decl
:= Parent
(Decl
);
4340 Insert_List_Before_And_Analyze
(Decl
, L
);
4348 ---------------------
4349 -- End_Use_Clauses --
4350 ---------------------
4352 procedure End_Use_Clauses
(Clause
: Node_Id
) is
4356 -- Remove Use_Type clauses first, because they affect the
4357 -- visibility of operators in subsequent used packages.
4360 while Present
(U
) loop
4361 if Nkind
(U
) = N_Use_Type_Clause
then
4365 Next_Use_Clause
(U
);
4369 while Present
(U
) loop
4370 if Nkind
(U
) = N_Use_Package_Clause
then
4371 End_Use_Package
(U
);
4374 Next_Use_Clause
(U
);
4376 end End_Use_Clauses
;
4378 ---------------------
4379 -- End_Use_Package --
4380 ---------------------
4382 procedure End_Use_Package
(N
: Node_Id
) is
4383 Pack_Name
: Node_Id
;
4388 function Is_Primitive_Operator_In_Use
4390 F
: Entity_Id
) return Boolean;
4391 -- Check whether Op is a primitive operator of a use-visible type
4393 ----------------------------------
4394 -- Is_Primitive_Operator_In_Use --
4395 ----------------------------------
4397 function Is_Primitive_Operator_In_Use
4399 F
: Entity_Id
) return Boolean
4401 T
: constant Entity_Id
:= Base_Type
(Etype
(F
));
4403 return In_Use
(T
) and then Scope
(T
) = Scope
(Op
);
4404 end Is_Primitive_Operator_In_Use
;
4406 -- Start of processing for End_Use_Package
4409 Pack_Name
:= First
(Names
(N
));
4410 while Present
(Pack_Name
) loop
4412 -- Test that Pack_Name actually denotes a package before processing
4414 if Is_Entity_Name
(Pack_Name
)
4415 and then Ekind
(Entity
(Pack_Name
)) = E_Package
4417 Pack
:= Entity
(Pack_Name
);
4419 if In_Open_Scopes
(Pack
) then
4422 elsif not Redundant_Use
(Pack_Name
) then
4423 Set_In_Use
(Pack
, False);
4424 Set_Current_Use_Clause
(Pack
, Empty
);
4426 Id
:= First_Entity
(Pack
);
4427 while Present
(Id
) loop
4429 -- Preserve use-visibility of operators that are primitive
4430 -- operators of a type that is use-visible through an active
4433 if Nkind
(Id
) = N_Defining_Operator_Symbol
4435 (Is_Primitive_Operator_In_Use
(Id
, First_Formal
(Id
))
4437 (Present
(Next_Formal
(First_Formal
(Id
)))
4439 Is_Primitive_Operator_In_Use
4440 (Id
, Next_Formal
(First_Formal
(Id
)))))
4444 Set_Is_Potentially_Use_Visible
(Id
, False);
4447 if Is_Private_Type
(Id
)
4448 and then Present
(Full_View
(Id
))
4450 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4456 if Present
(Renamed_Object
(Pack
)) then
4457 Set_In_Use
(Renamed_Object
(Pack
), False);
4458 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
4461 if Chars
(Pack
) = Name_System
4462 and then Scope
(Pack
) = Standard_Standard
4463 and then Present_System_Aux
4465 Id
:= First_Entity
(System_Aux_Id
);
4466 while Present
(Id
) loop
4467 Set_Is_Potentially_Use_Visible
(Id
, False);
4469 if Is_Private_Type
(Id
)
4470 and then Present
(Full_View
(Id
))
4472 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
4478 Set_In_Use
(System_Aux_Id
, False);
4482 Set_Redundant_Use
(Pack_Name
, False);
4489 if Present
(Hidden_By_Use_Clause
(N
)) then
4490 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
4491 while Present
(Elmt
) loop
4493 E
: constant Entity_Id
:= Node
(Elmt
);
4496 -- Reset either Use_Visibility or Direct_Visibility, depending
4497 -- on how the entity was hidden by the use clause.
4499 if In_Use
(Scope
(E
))
4500 and then Used_As_Generic_Actual
(Scope
(E
))
4502 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
4504 Set_Is_Immediately_Visible
(Node
(Elmt
));
4511 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
4513 end End_Use_Package
;
4519 procedure End_Use_Type
(N
: Node_Id
) is
4524 -- Start of processing for End_Use_Type
4527 Id
:= First
(Subtype_Marks
(N
));
4528 while Present
(Id
) loop
4530 -- A call to Rtsfind may occur while analyzing a use_type clause,
4531 -- in which case the type marks are not resolved yet, and there is
4532 -- nothing to remove.
4534 if not Is_Entity_Name
(Id
) or else No
(Entity
(Id
)) then
4540 if T
= Any_Type
or else From_Limited_With
(T
) then
4543 -- Note that the use_type clause may mention a subtype of the type
4544 -- whose primitive operations have been made visible. Here as
4545 -- elsewhere, it is the base type that matters for visibility.
4547 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
4550 elsif not Redundant_Use
(Id
) then
4551 Set_In_Use
(T
, False);
4552 Set_In_Use
(Base_Type
(T
), False);
4553 Set_Current_Use_Clause
(T
, Empty
);
4554 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
4561 if Is_Empty_Elmt_List
(Used_Operations
(N
)) then
4565 Elmt
:= First_Elmt
(Used_Operations
(N
));
4566 while Present
(Elmt
) loop
4567 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
4573 ----------------------
4574 -- Find_Direct_Name --
4575 ----------------------
4577 procedure Find_Direct_Name
(N
: Node_Id
) is
4582 Inst
: Entity_Id
:= Empty
;
4583 -- Enclosing instance, if any
4585 Homonyms
: Entity_Id
;
4586 -- Saves start of homonym chain
4588 Nvis_Entity
: Boolean;
4589 -- Set True to indicate that there is at least one entity on the homonym
4590 -- chain which, while not visible, is visible enough from the user point
4591 -- of view to warrant an error message of "not visible" rather than
4594 Nvis_Is_Private_Subprg
: Boolean := False;
4595 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
4596 -- effect concerning library subprograms has been detected. Used to
4597 -- generate the precise error message.
4599 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
4600 -- Returns true if the entity is an actual for a package that is itself
4601 -- an actual for a formal package of the current instance. Such an
4602 -- entity requires special handling because it may be use-visible but
4603 -- hides directly visible entities defined outside the instance, because
4604 -- the corresponding formal did so in the generic.
4606 function Is_Actual_Parameter
return Boolean;
4607 -- This function checks if the node N is an identifier that is an actual
4608 -- parameter of a procedure call. If so it returns True, otherwise it
4609 -- return False. The reason for this check is that at this stage we do
4610 -- not know what procedure is being called if the procedure might be
4611 -- overloaded, so it is premature to go setting referenced flags or
4612 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
4613 -- for that processing
4615 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
4616 -- This function determines whether a reference to the entity E, which
4617 -- is not visible, can reasonably be considered to be known to the
4618 -- writer of the reference. This is a heuristic test, used only for
4619 -- the purposes of figuring out whether we prefer to complain that an
4620 -- entity is undefined or invisible (and identify the declaration of
4621 -- the invisible entity in the latter case). The point here is that we
4622 -- don't want to complain that something is invisible and then point to
4623 -- something entirely mysterious to the writer.
4625 procedure Nvis_Messages
;
4626 -- Called if there are no visible entries for N, but there is at least
4627 -- one non-directly visible, or hidden declaration. This procedure
4628 -- outputs an appropriate set of error messages.
4630 procedure Undefined
(Nvis
: Boolean);
4631 -- This function is called if the current node has no corresponding
4632 -- visible entity or entities. The value set in Msg indicates whether
4633 -- an error message was generated (multiple error messages for the
4634 -- same variable are generally suppressed, see body for details).
4635 -- Msg is True if an error message was generated, False if not. This
4636 -- value is used by the caller to determine whether or not to output
4637 -- additional messages where appropriate. The parameter is set False
4638 -- to get the message "X is undefined", and True to get the message
4639 -- "X is not visible".
4641 -------------------------
4642 -- From_Actual_Package --
4643 -------------------------
4645 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
4646 Scop
: constant Entity_Id
:= Scope
(E
);
4647 -- Declared scope of candidate entity
4651 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean;
4652 -- Recursive function that does the work and examines actuals of
4653 -- actual packages of current instance.
4655 ------------------------
4656 -- Declared_In_Actual --
4657 ------------------------
4659 function Declared_In_Actual
(Pack
: Entity_Id
) return Boolean is
4663 if No
(Associated_Formal_Package
(Pack
)) then
4667 Act
:= First_Entity
(Pack
);
4668 while Present
(Act
) loop
4669 if Renamed_Object
(Pack
) = Scop
then
4672 -- Check for end of list of actuals.
4674 elsif Ekind
(Act
) = E_Package
4675 and then Renamed_Object
(Act
) = Pack
4679 elsif Ekind
(Act
) = E_Package
4680 and then Declared_In_Actual
(Act
)
4690 end Declared_In_Actual
;
4692 -- Start of processing for From_Actual_Package
4695 if not In_Instance
then
4699 Inst
:= Current_Scope
;
4700 while Present
(Inst
)
4701 and then Ekind
(Inst
) /= E_Package
4702 and then not Is_Generic_Instance
(Inst
)
4704 Inst
:= Scope
(Inst
);
4711 Act
:= First_Entity
(Inst
);
4712 while Present
(Act
) loop
4713 if Ekind
(Act
) = E_Package
4714 and then Declared_In_Actual
(Act
)
4724 end From_Actual_Package
;
4726 -------------------------
4727 -- Is_Actual_Parameter --
4728 -------------------------
4730 function Is_Actual_Parameter
return Boolean is
4733 Nkind
(N
) = N_Identifier
4735 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
4737 (Nkind
(Parent
(N
)) = N_Parameter_Association
4738 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
4739 and then Nkind
(Parent
(Parent
(N
))) =
4740 N_Procedure_Call_Statement
));
4741 end Is_Actual_Parameter
;
4743 -------------------------
4744 -- Known_But_Invisible --
4745 -------------------------
4747 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
4748 Fname
: File_Name_Type
;
4751 -- Entities in Standard are always considered to be known
4753 if Sloc
(E
) <= Standard_Location
then
4756 -- An entity that does not come from source is always considered
4757 -- to be unknown, since it is an artifact of code expansion.
4759 elsif not Comes_From_Source
(E
) then
4762 -- In gnat internal mode, we consider all entities known. The
4763 -- historical reason behind this discrepancy is not known??? But the
4764 -- only effect is to modify the error message given, so it is not
4765 -- critical. Since it only affects the exact wording of error
4766 -- messages in illegal programs, we do not mention this as an
4767 -- effect of -gnatg, since it is not a language modification.
4769 elsif GNAT_Mode
then
4773 -- Here we have an entity that is not from package Standard, and
4774 -- which comes from Source. See if it comes from an internal file.
4776 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
4778 -- Case of from internal file
4780 if Is_Internal_File_Name
(Fname
) then
4782 -- Private part entities in internal files are never considered
4783 -- to be known to the writer of normal application code.
4785 if Is_Hidden
(E
) then
4789 -- Entities from System packages other than System and
4790 -- System.Storage_Elements are not considered to be known.
4791 -- System.Auxxxx files are also considered known to the user.
4793 -- Should refine this at some point to generally distinguish
4794 -- between known and unknown internal files ???
4796 Get_Name_String
(Fname
);
4801 Name_Buffer
(1 .. 2) /= "s-"
4803 Name_Buffer
(3 .. 8) = "stoele"
4805 Name_Buffer
(3 .. 5) = "aux";
4807 -- If not an internal file, then entity is definitely known,
4808 -- even if it is in a private part (the message generated will
4809 -- note that it is in a private part)
4814 end Known_But_Invisible
;
4820 procedure Nvis_Messages
is
4821 Comp_Unit
: Node_Id
;
4823 Found
: Boolean := False;
4824 Hidden
: Boolean := False;
4828 -- Ada 2005 (AI-262): Generate a precise error concerning the
4829 -- Beaujolais effect that was previously detected
4831 if Nvis_Is_Private_Subprg
then
4833 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
4834 and then Ekind
(E2
) = E_Function
4835 and then Scope
(E2
) = Standard_Standard
4836 and then Has_Private_With
(E2
));
4838 -- Find the sloc corresponding to the private with'ed unit
4840 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
4841 Error_Msg_Sloc
:= No_Location
;
4843 Item
:= First
(Context_Items
(Comp_Unit
));
4844 while Present
(Item
) loop
4845 if Nkind
(Item
) = N_With_Clause
4846 and then Private_Present
(Item
)
4847 and then Entity
(Name
(Item
)) = E2
4849 Error_Msg_Sloc
:= Sloc
(Item
);
4856 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
4858 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
4862 Undefined
(Nvis
=> True);
4866 -- First loop does hidden declarations
4869 while Present
(Ent
) loop
4870 if Is_Potentially_Use_Visible
(Ent
) then
4872 Error_Msg_N
-- CODEFIX
4873 ("multiple use clauses cause hiding!", N
);
4877 Error_Msg_Sloc
:= Sloc
(Ent
);
4878 Error_Msg_N
-- CODEFIX
4879 ("hidden declaration#!", N
);
4882 Ent
:= Homonym
(Ent
);
4885 -- If we found hidden declarations, then that's enough, don't
4886 -- bother looking for non-visible declarations as well.
4892 -- Second loop does non-directly visible declarations
4895 while Present
(Ent
) loop
4896 if not Is_Potentially_Use_Visible
(Ent
) then
4898 -- Do not bother the user with unknown entities
4900 if not Known_But_Invisible
(Ent
) then
4904 Error_Msg_Sloc
:= Sloc
(Ent
);
4906 -- Output message noting that there is a non-visible
4907 -- declaration, distinguishing the private part case.
4909 if Is_Hidden
(Ent
) then
4910 Error_Msg_N
("non-visible (private) declaration#!", N
);
4912 -- If the entity is declared in a generic package, it
4913 -- cannot be visible, so there is no point in adding it
4914 -- to the list of candidates if another homograph from a
4915 -- non-generic package has been seen.
4917 elsif Ekind
(Scope
(Ent
)) = E_Generic_Package
4923 Error_Msg_N
-- CODEFIX
4924 ("non-visible declaration#!", N
);
4926 if Ekind
(Scope
(Ent
)) /= E_Generic_Package
then
4930 if Is_Compilation_Unit
(Ent
)
4932 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
4934 Error_Msg_Qual_Level
:= 99;
4935 Error_Msg_NE
-- CODEFIX
4936 ("\\missing `WITH &;`", N
, Ent
);
4937 Error_Msg_Qual_Level
:= 0;
4940 if Ekind
(Ent
) = E_Discriminant
4941 and then Present
(Corresponding_Discriminant
(Ent
))
4942 and then Scope
(Corresponding_Discriminant
(Ent
)) =
4946 ("inherited discriminant not allowed here" &
4947 " (RM 3.8 (12), 3.8.1 (6))!", N
);
4951 -- Set entity and its containing package as referenced. We
4952 -- can't be sure of this, but this seems a better choice
4953 -- to avoid unused entity messages.
4955 if Comes_From_Source
(Ent
) then
4956 Set_Referenced
(Ent
);
4957 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
4962 Ent
:= Homonym
(Ent
);
4971 procedure Undefined
(Nvis
: Boolean) is
4972 Emsg
: Error_Msg_Id
;
4975 -- We should never find an undefined internal name. If we do, then
4976 -- see if we have previous errors. If so, ignore on the grounds that
4977 -- it is probably a cascaded message (e.g. a block label from a badly
4978 -- formed block). If no previous errors, then we have a real internal
4979 -- error of some kind so raise an exception.
4981 if Is_Internal_Name
(Chars
(N
)) then
4982 if Total_Errors_Detected
/= 0 then
4985 raise Program_Error
;
4989 -- A very specialized error check, if the undefined variable is
4990 -- a case tag, and the case type is an enumeration type, check
4991 -- for a possible misspelling, and if so, modify the identifier
4993 -- Named aggregate should also be handled similarly ???
4995 if Nkind
(N
) = N_Identifier
4996 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
4999 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
5000 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
5005 if Is_Enumeration_Type
(Case_Typ
)
5006 and then not Is_Standard_Character_Type
(Case_Typ
)
5008 Lit
:= First_Literal
(Case_Typ
);
5009 Get_Name_String
(Chars
(Lit
));
5011 if Chars
(Lit
) /= Chars
(N
)
5012 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
))
5014 Error_Msg_Node_2
:= Lit
;
5015 Error_Msg_N
-- CODEFIX
5016 ("& is undefined, assume misspelling of &", N
);
5017 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
5021 Lit
:= Next_Literal
(Lit
);
5026 -- Normal processing
5028 Set_Entity
(N
, Any_Id
);
5029 Set_Etype
(N
, Any_Type
);
5031 -- We use the table Urefs to keep track of entities for which we
5032 -- have issued errors for undefined references. Multiple errors
5033 -- for a single name are normally suppressed, however we modify
5034 -- the error message to alert the programmer to this effect.
5036 for J
in Urefs
.First
.. Urefs
.Last
loop
5037 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
5038 if Urefs
.Table
(J
).Err
/= No_Error_Msg
5039 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
5041 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
5043 if Urefs
.Table
(J
).Nvis
then
5044 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5045 "& is not visible (more references follow)");
5047 Change_Error_Text
(Urefs
.Table
(J
).Err
,
5048 "& is undefined (more references follow)");
5051 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
5054 -- Although we will set Msg False, and thus suppress the
5055 -- message, we also set Error_Posted True, to avoid any
5056 -- cascaded messages resulting from the undefined reference.
5059 Set_Error_Posted
(N
, True);
5064 -- If entry not found, this is first undefined occurrence
5067 Error_Msg_N
("& is not visible!", N
);
5071 Error_Msg_N
("& is undefined!", N
);
5074 -- A very bizarre special check, if the undefined identifier
5075 -- is put or put_line, then add a special error message (since
5076 -- this is a very common error for beginners to make).
5078 if Nam_In
(Chars
(N
), Name_Put
, Name_Put_Line
) then
5079 Error_Msg_N
-- CODEFIX
5080 ("\\possible missing `WITH Ada.Text_'I'O; " &
5081 "USE Ada.Text_'I'O`!", N
);
5083 -- Another special check if N is the prefix of a selected
5084 -- component which is a known unit, add message complaining
5085 -- about missing with for this unit.
5087 elsif Nkind
(Parent
(N
)) = N_Selected_Component
5088 and then N
= Prefix
(Parent
(N
))
5089 and then Is_Known_Unit
(Parent
(N
))
5091 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
5092 Error_Msg_N
-- CODEFIX
5093 ("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
5096 -- Now check for possible misspellings
5100 Ematch
: Entity_Id
:= Empty
;
5102 Last_Name_Id
: constant Name_Id
:=
5103 Name_Id
(Nat
(First_Name_Id
) +
5104 Name_Entries_Count
- 1);
5107 for Nam
in First_Name_Id
.. Last_Name_Id
loop
5108 E
:= Get_Name_Entity_Id
(Nam
);
5111 and then (Is_Immediately_Visible
(E
)
5113 Is_Potentially_Use_Visible
(E
))
5115 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
5122 if Present
(Ematch
) then
5123 Error_Msg_NE
-- CODEFIX
5124 ("\possible misspelling of&", N
, Ematch
);
5129 -- Make entry in undefined references table unless the full errors
5130 -- switch is set, in which case by refraining from generating the
5131 -- table entry, we guarantee that we get an error message for every
5132 -- undefined reference.
5134 if not All_Errors_Mode
then
5145 -- Start of processing for Find_Direct_Name
5148 -- If the entity pointer is already set, this is an internal node, or
5149 -- a node that is analyzed more than once, after a tree modification.
5150 -- In such a case there is no resolution to perform, just set the type.
5152 if Present
(Entity
(N
)) then
5153 if Is_Type
(Entity
(N
)) then
5154 Set_Etype
(N
, Entity
(N
));
5158 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
5161 -- One special case here. If the Etype field is already set,
5162 -- and references the packed array type corresponding to the
5163 -- etype of the referenced entity, then leave it alone. This
5164 -- happens for trees generated from Exp_Pakd, where expressions
5165 -- can be deliberately "mis-typed" to the packed array type.
5167 if Is_Array_Type
(Entyp
)
5168 and then Is_Packed
(Entyp
)
5169 and then Present
(Etype
(N
))
5170 and then Etype
(N
) = Packed_Array_Impl_Type
(Entyp
)
5174 -- If not that special case, then just reset the Etype
5177 Set_Etype
(N
, Etype
(Entity
(N
)));
5185 -- Here if Entity pointer was not set, we need full visibility analysis
5186 -- First we generate debugging output if the debug E flag is set.
5188 if Debug_Flag_E
then
5189 Write_Str
("Looking for ");
5190 Write_Name
(Chars
(N
));
5194 Homonyms
:= Current_Entity
(N
);
5195 Nvis_Entity
:= False;
5198 while Present
(E
) loop
5200 -- If entity is immediately visible or potentially use visible, then
5201 -- process the entity and we are done.
5203 if Is_Immediately_Visible
(E
) then
5204 goto Immediately_Visible_Entity
;
5206 elsif Is_Potentially_Use_Visible
(E
) then
5207 goto Potentially_Use_Visible_Entity
;
5209 -- Note if a known but invisible entity encountered
5211 elsif Known_But_Invisible
(E
) then
5212 Nvis_Entity
:= True;
5215 -- Move to next entity in chain and continue search
5220 -- If no entries on homonym chain that were potentially visible,
5221 -- and no entities reasonably considered as non-visible, then
5222 -- we have a plain undefined reference, with no additional
5223 -- explanation required.
5225 if not Nvis_Entity
then
5226 Undefined
(Nvis
=> False);
5228 -- Otherwise there is at least one entry on the homonym chain that
5229 -- is reasonably considered as being known and non-visible.
5237 -- Processing for a potentially use visible entry found. We must search
5238 -- the rest of the homonym chain for two reasons. First, if there is a
5239 -- directly visible entry, then none of the potentially use-visible
5240 -- entities are directly visible (RM 8.4(10)). Second, we need to check
5241 -- for the case of multiple potentially use-visible entries hiding one
5242 -- another and as a result being non-directly visible (RM 8.4(11)).
5244 <<Potentially_Use_Visible_Entity
>> declare
5245 Only_One_Visible
: Boolean := True;
5246 All_Overloadable
: Boolean := Is_Overloadable
(E
);
5250 while Present
(E2
) loop
5251 if Is_Immediately_Visible
(E2
) then
5253 -- If the use-visible entity comes from the actual for a
5254 -- formal package, it hides a directly visible entity from
5255 -- outside the instance.
5257 if From_Actual_Package
(E
)
5258 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
5263 goto Immediately_Visible_Entity
;
5266 elsif Is_Potentially_Use_Visible
(E2
) then
5267 Only_One_Visible
:= False;
5268 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
5270 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
5271 -- that can occur in private_with clauses. Example:
5274 -- private with B; package A is
5275 -- package C is function B return Integer;
5277 -- V1 : Integer := B;
5278 -- private function B return Integer;
5279 -- V2 : Integer := B;
5282 -- V1 resolves to A.B, but V2 resolves to library unit B
5284 elsif Ekind
(E2
) = E_Function
5285 and then Scope
(E2
) = Standard_Standard
5286 and then Has_Private_With
(E2
)
5288 Only_One_Visible
:= False;
5289 All_Overloadable
:= False;
5290 Nvis_Is_Private_Subprg
:= True;
5297 -- On falling through this loop, we have checked that there are no
5298 -- immediately visible entities. Only_One_Visible is set if exactly
5299 -- one potentially use visible entity exists. All_Overloadable is
5300 -- set if all the potentially use visible entities are overloadable.
5301 -- The condition for legality is that either there is one potentially
5302 -- use visible entity, or if there is more than one, then all of them
5303 -- are overloadable.
5305 if Only_One_Visible
or All_Overloadable
then
5308 -- If there is more than one potentially use-visible entity and at
5309 -- least one of them non-overloadable, we have an error (RM 8.4(11)).
5310 -- Note that E points to the first such entity on the homonym list.
5311 -- Special case: if one of the entities is declared in an actual
5312 -- package, it was visible in the generic, and takes precedence over
5313 -- other entities that are potentially use-visible. Same if it is
5314 -- declared in a local instantiation of the current instance.
5319 -- Find current instance
5321 Inst
:= Current_Scope
;
5322 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
5323 if Is_Generic_Instance
(Inst
) then
5327 Inst
:= Scope
(Inst
);
5331 while Present
(E2
) loop
5332 if From_Actual_Package
(E2
)
5334 (Is_Generic_Instance
(Scope
(E2
))
5335 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
5348 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5350 -- A use-clause in the body of a system file creates conflict
5351 -- with some entity in a user scope, while rtsfind is active.
5352 -- Keep only the entity coming from another predefined unit.
5355 while Present
(E2
) loop
5356 if Is_Predefined_File_Name
5357 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
5366 -- Entity must exist because predefined unit is correct
5368 raise Program_Error
;
5377 -- Come here with E set to the first immediately visible entity on
5378 -- the homonym chain. This is the one we want unless there is another
5379 -- immediately visible entity further on in the chain for an inner
5380 -- scope (RM 8.3(8)).
5382 <<Immediately_Visible_Entity
>> declare
5387 -- Find scope level of initial entity. When compiling through
5388 -- Rtsfind, the previous context is not completely invisible, and
5389 -- an outer entity may appear on the chain, whose scope is below
5390 -- the entry for Standard that delimits the current scope stack.
5391 -- Indicate that the level for this spurious entry is outside of
5392 -- the current scope stack.
5394 Level
:= Scope_Stack
.Last
;
5396 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
5397 exit when Scop
= Scope
(E
);
5399 exit when Scop
= Standard_Standard
;
5402 -- Now search remainder of homonym chain for more inner entry
5403 -- If the entity is Standard itself, it has no scope, and we
5404 -- compare it with the stack entry directly.
5407 while Present
(E2
) loop
5408 if Is_Immediately_Visible
(E2
) then
5410 -- If a generic package contains a local declaration that
5411 -- has the same name as the generic, there may be a visibility
5412 -- conflict in an instance, where the local declaration must
5413 -- also hide the name of the corresponding package renaming.
5414 -- We check explicitly for a package declared by a renaming,
5415 -- whose renamed entity is an instance that is on the scope
5416 -- stack, and that contains a homonym in the same scope. Once
5417 -- we have found it, we know that the package renaming is not
5418 -- immediately visible, and that the identifier denotes the
5419 -- other entity (and its homonyms if overloaded).
5421 if Scope
(E
) = Scope
(E2
)
5422 and then Ekind
(E
) = E_Package
5423 and then Present
(Renamed_Object
(E
))
5424 and then Is_Generic_Instance
(Renamed_Object
(E
))
5425 and then In_Open_Scopes
(Renamed_Object
(E
))
5426 and then Comes_From_Source
(N
)
5428 Set_Is_Immediately_Visible
(E
, False);
5432 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
5433 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
5434 or else Scope_Stack
.Table
(J
).Entity
= E2
5447 -- At the end of that loop, E is the innermost immediately
5448 -- visible entity, so we are all set.
5451 -- Come here with entity found, and stored in E
5455 -- Check violation of No_Wide_Characters restriction
5457 Check_Wide_Character_Restriction
(E
, N
);
5459 -- When distribution features are available (Get_PCS_Name /=
5460 -- Name_No_DSA), a remote access-to-subprogram type is converted
5461 -- into a record type holding whatever information is needed to
5462 -- perform a remote call on an RCI subprogram. In that case we
5463 -- rewrite any occurrence of the RAS type into the equivalent record
5464 -- type here. 'Access attribute references and RAS dereferences are
5465 -- then implemented using specific TSSs. However when distribution is
5466 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
5467 -- generation of these TSSs, and we must keep the RAS type in its
5468 -- original access-to-subprogram form (since all calls through a
5469 -- value of such type will be local anyway in the absence of a PCS).
5471 if Comes_From_Source
(N
)
5472 and then Is_Remote_Access_To_Subprogram_Type
(E
)
5473 and then Ekind
(E
) = E_Access_Subprogram_Type
5474 and then Expander_Active
5475 and then Get_PCS_Name
/= Name_No_DSA
5477 Rewrite
(N
, New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
5481 -- Set the entity. Note that the reason we call Set_Entity for the
5482 -- overloadable case, as opposed to Set_Entity_With_Checks is
5483 -- that in the overloaded case, the initial call can set the wrong
5484 -- homonym. The call that sets the right homonym is in Sem_Res and
5485 -- that call does use Set_Entity_With_Checks, so we don't miss
5488 if Is_Overloadable
(E
) then
5491 Set_Entity_With_Checks
(N
, E
);
5497 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
5500 if Debug_Flag_E
then
5501 Write_Str
(" found ");
5502 Write_Entity_Info
(E
, " ");
5505 -- If the Ekind of the entity is Void, it means that all homonyms
5506 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
5507 -- test is skipped if the current scope is a record and the name is
5508 -- a pragma argument expression (case of Atomic and Volatile pragmas
5509 -- and possibly other similar pragmas added later, which are allowed
5510 -- to reference components in the current record).
5512 if Ekind
(E
) = E_Void
5514 (not Is_Record_Type
(Current_Scope
)
5515 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
5517 Premature_Usage
(N
);
5519 -- If the entity is overloadable, collect all interpretations of the
5520 -- name for subsequent overload resolution. We optimize a bit here to
5521 -- do this only if we have an overloadable entity that is not on its
5522 -- own on the homonym chain.
5524 elsif Is_Overloadable
(E
)
5525 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
5527 Collect_Interps
(N
);
5529 -- If no homonyms were visible, the entity is unambiguous
5531 if not Is_Overloaded
(N
) then
5532 if not Is_Actual_Parameter
then
5533 Generate_Reference
(E
, N
);
5537 -- Case of non-overloadable entity, set the entity providing that
5538 -- we do not have the case of a discriminant reference within a
5539 -- default expression. Such references are replaced with the
5540 -- corresponding discriminal, which is the formal corresponding to
5541 -- to the discriminant in the initialization procedure.
5544 -- Entity is unambiguous, indicate that it is referenced here
5546 -- For a renaming of an object, always generate simple reference,
5547 -- we don't try to keep track of assignments in this case, except
5548 -- in SPARK mode where renamings are traversed for generating
5549 -- local effects of subprograms.
5552 and then Present
(Renamed_Object
(E
))
5553 and then not GNATprove_Mode
5555 Generate_Reference
(E
, N
);
5557 -- If the renamed entity is a private protected component,
5558 -- reference the original component as well. This needs to be
5559 -- done because the private renamings are installed before any
5560 -- analysis has occurred. Reference to a private component will
5561 -- resolve to the renaming and the original component will be
5562 -- left unreferenced, hence the following.
5564 if Is_Prival
(E
) then
5565 Generate_Reference
(Prival_Link
(E
), N
);
5568 -- One odd case is that we do not want to set the Referenced flag
5569 -- if the entity is a label, and the identifier is the label in
5570 -- the source, since this is not a reference from the point of
5571 -- view of the user.
5573 elsif Nkind
(Parent
(N
)) = N_Label
then
5575 R
: constant Boolean := Referenced
(E
);
5578 -- Generate reference unless this is an actual parameter
5579 -- (see comment below)
5581 if Is_Actual_Parameter
then
5582 Generate_Reference
(E
, N
);
5583 Set_Referenced
(E
, R
);
5587 -- Normal case, not a label: generate reference
5590 if not Is_Actual_Parameter
then
5592 -- Package or generic package is always a simple reference
5594 if Ekind_In
(E
, E_Package
, E_Generic_Package
) then
5595 Generate_Reference
(E
, N
, 'r');
5597 -- Else see if we have a left hand side
5602 Generate_Reference
(E
, N
, 'm');
5605 Generate_Reference
(E
, N
, 'r');
5607 -- If we don't know now, generate reference later
5610 Deferred_References
.Append
((E
, N
));
5616 Set_Entity_Or_Discriminal
(N
, E
);
5618 -- The name may designate a generalized reference, in which case
5619 -- the dereference interpretation will be included. Context is
5620 -- one in which a name is legal.
5622 if Ada_Version
>= Ada_2012
5624 (Nkind
(Parent
(N
)) in N_Subexpr
5625 or else Nkind_In
(Parent
(N
), N_Assignment_Statement
,
5626 N_Object_Declaration
,
5627 N_Parameter_Association
))
5629 Check_Implicit_Dereference
(N
, Etype
(E
));
5634 -- Come here with entity set
5637 Check_Restriction_No_Use_Of_Entity
(N
);
5638 end Find_Direct_Name
;
5640 ------------------------
5641 -- Find_Expanded_Name --
5642 ------------------------
5644 -- This routine searches the homonym chain of the entity until it finds
5645 -- an entity declared in the scope denoted by the prefix. If the entity
5646 -- is private, it may nevertheless be immediately visible, if we are in
5647 -- the scope of its declaration.
5649 procedure Find_Expanded_Name
(N
: Node_Id
) is
5650 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean;
5651 -- Determine whether expanded name Nod appears within a pragma which is
5652 -- a suitable context for an abstract view of a state or variable. The
5653 -- following pragmas fall in this category:
5660 -- In addition, pragma Abstract_State is also considered suitable even
5661 -- though it is an illegal context for an abstract view as this allows
5662 -- for proper resolution of abstract views of variables. This illegal
5663 -- context is later flagged in the analysis of indicator Part_Of.
5665 -----------------------------
5666 -- In_Abstract_View_Pragma --
5667 -----------------------------
5669 function In_Abstract_View_Pragma
(Nod
: Node_Id
) return Boolean is
5673 -- Climb the parent chain looking for a pragma
5676 while Present
(Par
) loop
5677 if Nkind
(Par
) = N_Pragma
then
5678 if Nam_In
(Pragma_Name
(Par
), Name_Abstract_State
,
5682 Name_Refined_Depends
,
5683 Name_Refined_Global
)
5687 -- Otherwise the pragma is not a legal context for an abstract
5694 -- Prevent the search from going too far
5696 elsif Is_Body_Or_Package_Declaration
(Par
) then
5700 Par
:= Parent
(Par
);
5704 end In_Abstract_View_Pragma
;
5708 Selector
: constant Node_Id
:= Selector_Name
(N
);
5709 Candidate
: Entity_Id
:= Empty
;
5713 -- Start of processing for Find_Expanded_Name
5716 P_Name
:= Entity
(Prefix
(N
));
5718 -- If the prefix is a renamed package, look for the entity in the
5719 -- original package.
5721 if Ekind
(P_Name
) = E_Package
5722 and then Present
(Renamed_Object
(P_Name
))
5724 P_Name
:= Renamed_Object
(P_Name
);
5726 -- Rewrite node with entity field pointing to renamed object
5728 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
5729 Set_Entity
(Prefix
(N
), P_Name
);
5731 -- If the prefix is an object of a concurrent type, look for
5732 -- the entity in the associated task or protected type.
5734 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
5735 P_Name
:= Etype
(P_Name
);
5738 Id
:= Current_Entity
(Selector
);
5741 Is_New_Candidate
: Boolean;
5744 while Present
(Id
) loop
5745 if Scope
(Id
) = P_Name
then
5747 Is_New_Candidate
:= True;
5749 -- Handle abstract views of states and variables. These are
5750 -- acceptable candidates only when the reference to the view
5751 -- appears in certain pragmas.
5753 if Ekind
(Id
) = E_Abstract_State
5754 and then From_Limited_With
(Id
)
5755 and then Present
(Non_Limited_View
(Id
))
5757 if In_Abstract_View_Pragma
(N
) then
5758 Candidate
:= Non_Limited_View
(Id
);
5759 Is_New_Candidate
:= True;
5761 -- Hide the candidate because it is not used in a proper
5766 Is_New_Candidate
:= False;
5770 -- Ada 2005 (AI-217): Handle shadow entities associated with
5771 -- types declared in limited-withed nested packages. We don't need
5772 -- to handle E_Incomplete_Subtype entities because the entities
5773 -- in the limited view are always E_Incomplete_Type and
5774 -- E_Class_Wide_Type entities (see Build_Limited_Views).
5776 -- Regarding the expression used to evaluate the scope, it
5777 -- is important to note that the limited view also has shadow
5778 -- entities associated nested packages. For this reason the
5779 -- correct scope of the entity is the scope of the real entity.
5780 -- The non-limited view may itself be incomplete, in which case
5781 -- get the full view if available.
5783 elsif Ekind_In
(Id
, E_Incomplete_Type
, E_Class_Wide_Type
)
5784 and then From_Limited_With
(Id
)
5785 and then Present
(Non_Limited_View
(Id
))
5786 and then Scope
(Non_Limited_View
(Id
)) = P_Name
5788 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
5789 Is_New_Candidate
:= True;
5792 Is_New_Candidate
:= False;
5795 if Is_New_Candidate
then
5797 -- If entity is a child unit, either it is a visible child of
5798 -- the prefix, or we are in the body of a generic prefix, as
5799 -- will happen when a child unit is instantiated in the body
5800 -- of a generic parent. This is because the instance body does
5801 -- not restore the full compilation context, given that all
5802 -- non-local references have been captured.
5804 if Is_Child_Unit
(Id
) or else P_Name
= Standard_Standard
then
5805 exit when Is_Visible_Lib_Unit
(Id
)
5806 or else (Is_Child_Unit
(Id
)
5807 and then In_Open_Scopes
(Scope
(Id
))
5808 and then In_Instance_Body
);
5810 exit when not Is_Hidden
(Id
);
5813 exit when Is_Immediately_Visible
(Id
);
5821 and then Ekind_In
(P_Name
, E_Procedure
, E_Function
)
5822 and then Is_Generic_Instance
(P_Name
)
5824 -- Expanded name denotes entity in (instance of) generic subprogram.
5825 -- The entity may be in the subprogram instance, or may denote one of
5826 -- the formals, which is declared in the enclosing wrapper package.
5828 P_Name
:= Scope
(P_Name
);
5830 Id
:= Current_Entity
(Selector
);
5831 while Present
(Id
) loop
5832 exit when Scope
(Id
) = P_Name
;
5837 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
5838 Set_Etype
(N
, Any_Type
);
5840 -- If we are looking for an entity defined in System, try to find it
5841 -- in the child package that may have been provided as an extension
5842 -- to System. The Extend_System pragma will have supplied the name of
5843 -- the extension, which may have to be loaded.
5845 if Chars
(P_Name
) = Name_System
5846 and then Scope
(P_Name
) = Standard_Standard
5847 and then Present
(System_Extend_Unit
)
5848 and then Present_System_Aux
(N
)
5850 Set_Entity
(Prefix
(N
), System_Aux_Id
);
5851 Find_Expanded_Name
(N
);
5854 -- There is an implicit instance of the predefined operator in
5855 -- the given scope. The operator entity is defined in Standard.
5856 -- Has_Implicit_Operator makes the node into an Expanded_Name.
5858 elsif Nkind
(Selector
) = N_Operator_Symbol
5859 and then Has_Implicit_Operator
(N
)
5863 -- If there is no literal defined in the scope denoted by the
5864 -- prefix, the literal may belong to (a type derived from)
5865 -- Standard_Character, for which we have no explicit literals.
5867 elsif Nkind
(Selector
) = N_Character_Literal
5868 and then Has_Implicit_Character_Literal
(N
)
5873 -- If the prefix is a single concurrent object, use its name in
5874 -- the error message, rather than that of the anonymous type.
5876 if Is_Concurrent_Type
(P_Name
)
5877 and then Is_Internal_Name
(Chars
(P_Name
))
5879 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
5881 Error_Msg_Node_2
:= P_Name
;
5884 if P_Name
= System_Aux_Id
then
5885 P_Name
:= Scope
(P_Name
);
5886 Set_Entity
(Prefix
(N
), P_Name
);
5889 if Present
(Candidate
) then
5891 -- If we know that the unit is a child unit we can give a more
5892 -- accurate error message.
5894 if Is_Child_Unit
(Candidate
) then
5896 -- If the candidate is a private child unit and we are in
5897 -- the visible part of a public unit, specialize the error
5898 -- message. There might be a private with_clause for it,
5899 -- but it is not currently active.
5901 if Is_Private_Descendant
(Candidate
)
5902 and then Ekind
(Current_Scope
) = E_Package
5903 and then not In_Private_Part
(Current_Scope
)
5904 and then not Is_Private_Descendant
(Current_Scope
)
5907 ("private child unit& is not visible here", Selector
);
5909 -- Normal case where we have a missing with for a child unit
5912 Error_Msg_Qual_Level
:= 99;
5913 Error_Msg_NE
-- CODEFIX
5914 ("missing `WITH &;`", Selector
, Candidate
);
5915 Error_Msg_Qual_Level
:= 0;
5918 -- Here we don't know that this is a child unit
5921 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
5925 -- Within the instantiation of a child unit, the prefix may
5926 -- denote the parent instance, but the selector has the name
5927 -- of the original child. That is to say, when A.B appears
5928 -- within an instantiation of generic child unit B, the scope
5929 -- stack includes an instance of A (P_Name) and an instance
5930 -- of B under some other name. We scan the scope to find this
5931 -- child instance, which is the desired entity.
5932 -- Note that the parent may itself be a child instance, if
5933 -- the reference is of the form A.B.C, in which case A.B has
5934 -- already been rewritten with the proper entity.
5936 if In_Open_Scopes
(P_Name
)
5937 and then Is_Generic_Instance
(P_Name
)
5940 Gen_Par
: constant Entity_Id
:=
5941 Generic_Parent
(Specification
5942 (Unit_Declaration_Node
(P_Name
)));
5943 S
: Entity_Id
:= Current_Scope
;
5947 for J
in reverse 0 .. Scope_Stack
.Last
loop
5948 S
:= Scope_Stack
.Table
(J
).Entity
;
5950 exit when S
= Standard_Standard
;
5952 if Ekind_In
(S
, E_Function
,
5957 Generic_Parent
(Specification
5958 (Unit_Declaration_Node
(S
)));
5960 -- Check that P is a generic child of the generic
5961 -- parent of the prefix.
5964 and then Chars
(P
) = Chars
(Selector
)
5965 and then Scope
(P
) = Gen_Par
5976 -- If this is a selection from Ada, System or Interfaces, then
5977 -- we assume a missing with for the corresponding package.
5979 if Is_Known_Unit
(N
) then
5980 if not Error_Posted
(N
) then
5981 Error_Msg_Node_2
:= Selector
;
5982 Error_Msg_N
-- CODEFIX
5983 ("missing `WITH &.&;`", Prefix
(N
));
5986 -- If this is a selection from a dummy package, then suppress
5987 -- the error message, of course the entity is missing if the
5988 -- package is missing.
5990 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
5993 -- Here we have the case of an undefined component
5996 -- The prefix may hide a homonym in the context that
5997 -- declares the desired entity. This error can use a
5998 -- specialized message.
6000 if In_Open_Scopes
(P_Name
) then
6002 H
: constant Entity_Id
:= Homonym
(P_Name
);
6006 and then Is_Compilation_Unit
(H
)
6008 (Is_Immediately_Visible
(H
)
6009 or else Is_Visible_Lib_Unit
(H
))
6011 Id
:= First_Entity
(H
);
6012 while Present
(Id
) loop
6013 if Chars
(Id
) = Chars
(Selector
) then
6014 Error_Msg_Qual_Level
:= 99;
6015 Error_Msg_Name_1
:= Chars
(Selector
);
6017 ("% not declared in&", N
, P_Name
);
6019 ("\use fully qualified name starting with "
6020 & "Standard to make& visible", N
, H
);
6021 Error_Msg_Qual_Level
:= 0;
6029 -- If not found, standard error message
6031 Error_Msg_NE
("& not declared in&", N
, Selector
);
6037 Error_Msg_NE
("& not declared in&", N
, Selector
);
6040 -- Check for misspelling of some entity in prefix
6042 Id
:= First_Entity
(P_Name
);
6043 while Present
(Id
) loop
6044 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
6045 and then not Is_Internal_Name
(Chars
(Id
))
6047 Error_Msg_NE
-- CODEFIX
6048 ("possible misspelling of&", Selector
, Id
);
6055 -- Specialize the message if this may be an instantiation
6056 -- of a child unit that was not mentioned in the context.
6058 if Nkind
(Parent
(N
)) = N_Package_Instantiation
6059 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
6060 and then Is_Compilation_Unit
6061 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
6063 Error_Msg_Node_2
:= Selector
;
6064 Error_Msg_N
-- CODEFIX
6065 ("\missing `WITH &.&;`", Prefix
(N
));
6075 if Comes_From_Source
(N
)
6076 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
6077 and then Ekind
(Id
) = E_Access_Subprogram_Type
6078 and then Present
(Equivalent_Type
(Id
))
6080 -- If we are not actually generating distribution code (i.e. the
6081 -- current PCS is the dummy non-distributed version), then the
6082 -- Equivalent_Type will be missing, and Id should be treated as
6083 -- a regular access-to-subprogram type.
6085 Id
:= Equivalent_Type
(Id
);
6086 Set_Chars
(Selector
, Chars
(Id
));
6089 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
6091 if Ekind
(P_Name
) = E_Package
and then From_Limited_With
(P_Name
) then
6092 if From_Limited_With
(Id
)
6093 or else Is_Type
(Id
)
6094 or else Ekind
(Id
) = E_Package
6099 ("limited withed package can only be used to access "
6100 & "incomplete types", N
);
6104 if Is_Task_Type
(P_Name
)
6105 and then ((Ekind
(Id
) = E_Entry
6106 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
6108 (Ekind
(Id
) = E_Entry_Family
6110 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
6112 -- If both the task type and the entry are in scope, this may still
6113 -- be the expanded name of an entry formal.
6115 if In_Open_Scopes
(Id
)
6116 and then Nkind
(Parent
(N
)) = N_Selected_Component
6121 -- It is an entry call after all, either to the current task
6122 -- (which will deadlock) or to an enclosing task.
6124 Analyze_Selected_Component
(N
);
6129 Change_Selected_Component_To_Expanded_Name
(N
);
6131 -- Set appropriate type
6133 if Is_Type
(Id
) then
6136 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
6139 -- Do style check and generate reference, but skip both steps if this
6140 -- entity has homonyms, since we may not have the right homonym set yet.
6141 -- The proper homonym will be set during the resolve phase.
6143 if Has_Homonym
(Id
) then
6147 Set_Entity_Or_Discriminal
(N
, Id
);
6151 Generate_Reference
(Id
, N
, 'm');
6153 Generate_Reference
(Id
, N
, 'r');
6155 Deferred_References
.Append
((Id
, N
));
6159 -- Check for violation of No_Wide_Characters
6161 Check_Wide_Character_Restriction
(Id
, N
);
6163 -- If the Ekind of the entity is Void, it means that all homonyms are
6164 -- hidden from all visibility (RM 8.3(5,14-20)).
6166 if Ekind
(Id
) = E_Void
then
6167 Premature_Usage
(N
);
6169 elsif Is_Overloadable
(Id
) and then Present
(Homonym
(Id
)) then
6171 H
: Entity_Id
:= Homonym
(Id
);
6174 while Present
(H
) loop
6175 if Scope
(H
) = Scope
(Id
)
6176 and then (not Is_Hidden
(H
)
6177 or else Is_Immediately_Visible
(H
))
6179 Collect_Interps
(N
);
6186 -- If an extension of System is present, collect possible explicit
6187 -- overloadings declared in the extension.
6189 if Chars
(P_Name
) = Name_System
6190 and then Scope
(P_Name
) = Standard_Standard
6191 and then Present
(System_Extend_Unit
)
6192 and then Present_System_Aux
(N
)
6194 H
:= Current_Entity
(Id
);
6196 while Present
(H
) loop
6197 if Scope
(H
) = System_Aux_Id
then
6198 Add_One_Interp
(N
, H
, Etype
(H
));
6207 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6208 and then Scope
(Id
) /= Standard_Standard
6210 -- In addition to user-defined operators in the given scope, there
6211 -- may be an implicit instance of the predefined operator. The
6212 -- operator (defined in Standard) is found in Has_Implicit_Operator,
6213 -- and added to the interpretations. Procedure Add_One_Interp will
6214 -- determine which hides which.
6216 if Has_Implicit_Operator
(N
) then
6221 -- If there is a single interpretation for N we can generate a
6222 -- reference to the unique entity found.
6224 if Is_Overloadable
(Id
) and then not Is_Overloaded
(N
) then
6225 Generate_Reference
(Id
, N
);
6228 Check_Restriction_No_Use_Of_Entity
(N
);
6229 end Find_Expanded_Name
;
6231 -------------------------
6232 -- Find_Renamed_Entity --
6233 -------------------------
6235 function Find_Renamed_Entity
6239 Is_Actual
: Boolean := False) return Entity_Id
6242 I1
: Interp_Index
:= 0; -- Suppress junk warnings
6248 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
6249 -- If the renamed entity is an implicit operator, check whether it is
6250 -- visible because its operand type is properly visible. This check
6251 -- applies to explicit renamed entities that appear in the source in a
6252 -- renaming declaration or a formal subprogram instance, but not to
6253 -- default generic actuals with a name.
6255 function Report_Overload
return Entity_Id
;
6256 -- List possible interpretations, and specialize message in the
6257 -- case of a generic actual.
6259 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
6260 -- Determine whether a candidate subprogram is defined within the
6261 -- enclosing instance. If yes, it has precedence over outer candidates.
6263 --------------------------
6264 -- Is_Visible_Operation --
6265 --------------------------
6267 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
6273 if Ekind
(Op
) /= E_Operator
6274 or else Scope
(Op
) /= Standard_Standard
6275 or else (In_Instance
6276 and then (not Is_Actual
6277 or else Present
(Enclosing_Instance
)))
6282 -- For a fixed point type operator, check the resulting type,
6283 -- because it may be a mixed mode integer * fixed operation.
6285 if Present
(Next_Formal
(First_Formal
(New_S
)))
6286 and then Is_Fixed_Point_Type
(Etype
(New_S
))
6288 Typ
:= Etype
(New_S
);
6290 Typ
:= Etype
(First_Formal
(New_S
));
6293 Btyp
:= Base_Type
(Typ
);
6295 if Nkind
(Nam
) /= N_Expanded_Name
then
6296 return (In_Open_Scopes
(Scope
(Btyp
))
6297 or else Is_Potentially_Use_Visible
(Btyp
)
6298 or else In_Use
(Btyp
)
6299 or else In_Use
(Scope
(Btyp
)));
6302 Scop
:= Entity
(Prefix
(Nam
));
6304 if Ekind
(Scop
) = E_Package
6305 and then Present
(Renamed_Object
(Scop
))
6307 Scop
:= Renamed_Object
(Scop
);
6310 -- Operator is visible if prefix of expanded name denotes
6311 -- scope of type, or else type is defined in System_Aux
6312 -- and the prefix denotes System.
6314 return Scope
(Btyp
) = Scop
6315 or else (Scope
(Btyp
) = System_Aux_Id
6316 and then Scope
(Scope
(Btyp
)) = Scop
);
6319 end Is_Visible_Operation
;
6325 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
6329 Sc
:= Scope
(Inner
);
6330 while Sc
/= Standard_Standard
loop
6341 ---------------------
6342 -- Report_Overload --
6343 ---------------------
6345 function Report_Overload
return Entity_Id
is
6348 Error_Msg_NE
-- CODEFIX
6349 ("ambiguous actual subprogram&, " &
6350 "possible interpretations:", N
, Nam
);
6352 Error_Msg_N
-- CODEFIX
6353 ("ambiguous subprogram, " &
6354 "possible interpretations:", N
);
6357 List_Interps
(Nam
, N
);
6359 end Report_Overload
;
6361 -- Start of processing for Find_Renamed_Entity
6365 Candidate_Renaming
:= Empty
;
6367 if Is_Overloaded
(Nam
) then
6368 Get_First_Interp
(Nam
, Ind
, It
);
6369 while Present
(It
.Nam
) loop
6370 if Entity_Matches_Spec
(It
.Nam
, New_S
)
6371 and then Is_Visible_Operation
(It
.Nam
)
6373 if Old_S
/= Any_Id
then
6375 -- Note: The call to Disambiguate only happens if a
6376 -- previous interpretation was found, in which case I1
6377 -- has received a value.
6379 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
6381 if It1
= No_Interp
then
6382 Inst
:= Enclosing_Instance
;
6384 if Present
(Inst
) then
6385 if Within
(It
.Nam
, Inst
) then
6386 if Within
(Old_S
, Inst
) then
6388 -- Choose the innermost subprogram, which would
6389 -- have hidden the outer one in the generic.
6391 if Scope_Depth
(It
.Nam
) <
6400 elsif Within
(Old_S
, Inst
) then
6404 return Report_Overload
;
6407 -- If not within an instance, ambiguity is real
6410 return Report_Overload
;
6424 Present
(First_Formal
(It
.Nam
))
6425 and then Present
(First_Formal
(New_S
))
6426 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
))) =
6427 Base_Type
(Etype
(First_Formal
(New_S
))))
6429 Candidate_Renaming
:= It
.Nam
;
6432 Get_Next_Interp
(Ind
, It
);
6435 Set_Entity
(Nam
, Old_S
);
6437 if Old_S
/= Any_Id
then
6438 Set_Is_Overloaded
(Nam
, False);
6441 -- Non-overloaded case
6444 if Is_Actual
and then Present
(Enclosing_Instance
) then
6445 Old_S
:= Entity
(Nam
);
6447 elsif Entity_Matches_Spec
(Entity
(Nam
), New_S
) then
6448 Candidate_Renaming
:= New_S
;
6450 if Is_Visible_Operation
(Entity
(Nam
)) then
6451 Old_S
:= Entity
(Nam
);
6454 elsif Present
(First_Formal
(Entity
(Nam
)))
6455 and then Present
(First_Formal
(New_S
))
6456 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
)))) =
6457 Base_Type
(Etype
(First_Formal
(New_S
))))
6459 Candidate_Renaming
:= Entity
(Nam
);
6464 end Find_Renamed_Entity
;
6466 -----------------------------
6467 -- Find_Selected_Component --
6468 -----------------------------
6470 procedure Find_Selected_Component
(N
: Node_Id
) is
6471 P
: constant Node_Id
:= Prefix
(N
);
6474 -- Entity denoted by prefix
6481 function Available_Subtype
return Boolean;
6482 -- A small optimization: if the prefix is constrained and the component
6483 -- is an array type we may already have a usable subtype for it, so we
6484 -- can use it rather than generating a new one, because the bounds
6485 -- will be the values of the discriminants and not discriminant refs.
6486 -- This simplifies value tracing in GNATProve. For consistency, both
6487 -- the entity name and the subtype come from the constrained component.
6489 -- This is only used in GNATProve mode: when generating code it may be
6490 -- necessary to create an itype in the scope of use of the selected
6491 -- component, e.g. in the context of a expanded record equality.
6493 function Is_Reference_In_Subunit
return Boolean;
6494 -- In a subunit, the scope depth is not a proper measure of hiding,
6495 -- because the context of the proper body may itself hide entities in
6496 -- parent units. This rare case requires inspecting the tree directly
6497 -- because the proper body is inserted in the main unit and its context
6498 -- is simply added to that of the parent.
6500 -----------------------
6501 -- Available_Subtype --
6502 -----------------------
6504 function Available_Subtype
return Boolean is
6508 if GNATprove_Mode
then
6509 Comp
:= First_Entity
(Etype
(P
));
6510 while Present
(Comp
) loop
6511 if Chars
(Comp
) = Chars
(Selector_Name
(N
)) then
6512 Set_Etype
(N
, Etype
(Comp
));
6513 Set_Entity
(Selector_Name
(N
), Comp
);
6514 Set_Etype
(Selector_Name
(N
), Etype
(Comp
));
6518 Next_Component
(Comp
);
6523 end Available_Subtype
;
6525 -----------------------------
6526 -- Is_Reference_In_Subunit --
6527 -----------------------------
6529 function Is_Reference_In_Subunit
return Boolean is
6531 Comp_Unit
: Node_Id
;
6535 while Present
(Comp_Unit
)
6536 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
6538 Comp_Unit
:= Parent
(Comp_Unit
);
6541 if No
(Comp_Unit
) or else Nkind
(Unit
(Comp_Unit
)) /= N_Subunit
then
6545 -- Now check whether the package is in the context of the subunit
6547 Clause
:= First
(Context_Items
(Comp_Unit
));
6548 while Present
(Clause
) loop
6549 if Nkind
(Clause
) = N_With_Clause
6550 and then Entity
(Name
(Clause
)) = P_Name
6555 Clause
:= Next
(Clause
);
6559 end Is_Reference_In_Subunit
;
6561 -- Start of processing for Find_Selected_Component
6566 if Nkind
(P
) = N_Error
then
6570 -- Selector name cannot be a character literal or an operator symbol in
6571 -- SPARK, except for the operator symbol in a renaming.
6573 if Restriction_Check_Required
(SPARK_05
) then
6574 if Nkind
(Selector_Name
(N
)) = N_Character_Literal
then
6575 Check_SPARK_05_Restriction
6576 ("character literal cannot be prefixed", N
);
6577 elsif Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
6578 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
6580 Check_SPARK_05_Restriction
6581 ("operator symbol cannot be prefixed", N
);
6585 -- If the selector already has an entity, the node has been constructed
6586 -- in the course of expansion, and is known to be valid. Do not verify
6587 -- that it is defined for the type (it may be a private component used
6588 -- in the expansion of record equality).
6590 if Present
(Entity
(Selector_Name
(N
))) then
6591 if No
(Etype
(N
)) or else Etype
(N
) = Any_Type
then
6593 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
6594 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
6598 Set_Etype
(Sel_Name
, Etype
(Selector
));
6600 if not Is_Entity_Name
(P
) then
6604 -- Build an actual subtype except for the first parameter
6605 -- of an init proc, where this actual subtype is by
6606 -- definition incorrect, since the object is uninitialized
6607 -- (and does not even have defined discriminants etc.)
6609 if Is_Entity_Name
(P
)
6610 and then Ekind
(Entity
(P
)) = E_Function
6612 Nam
:= New_Copy
(P
);
6614 if Is_Overloaded
(P
) then
6615 Save_Interps
(P
, Nam
);
6618 Rewrite
(P
, Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6620 Analyze_Selected_Component
(N
);
6623 elsif Ekind
(Selector
) = E_Component
6624 and then (not Is_Entity_Name
(P
)
6625 or else Chars
(Entity
(P
)) /= Name_uInit
)
6627 -- Check if we already have an available subtype we can use
6629 if Ekind
(Etype
(P
)) = E_Record_Subtype
6630 and then Nkind
(Parent
(Etype
(P
))) = N_Subtype_Declaration
6631 and then Is_Array_Type
(Etype
(Selector
))
6632 and then not Is_Packed
(Etype
(Selector
))
6633 and then Available_Subtype
6637 -- Do not build the subtype when referencing components of
6638 -- dispatch table wrappers. Required to avoid generating
6639 -- elaboration code with HI runtimes.
6641 elsif RTU_Loaded
(Ada_Tags
)
6643 ((RTE_Available
(RE_Dispatch_Table_Wrapper
)
6644 and then Scope
(Selector
) =
6645 RTE
(RE_Dispatch_Table_Wrapper
))
6647 (RTE_Available
(RE_No_Dispatch_Table_Wrapper
)
6648 and then Scope
(Selector
) =
6649 RTE
(RE_No_Dispatch_Table_Wrapper
)))
6654 Build_Actual_Subtype_Of_Component
6655 (Etype
(Selector
), N
);
6662 if No
(C_Etype
) then
6663 C_Etype
:= Etype
(Selector
);
6665 Insert_Action
(N
, C_Etype
);
6666 C_Etype
:= Defining_Identifier
(C_Etype
);
6669 Set_Etype
(N
, C_Etype
);
6672 -- If this is the name of an entry or protected operation, and
6673 -- the prefix is an access type, insert an explicit dereference,
6674 -- so that entry calls are treated uniformly.
6676 if Is_Access_Type
(Etype
(P
))
6677 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
6680 New_P
: constant Node_Id
:=
6681 Make_Explicit_Dereference
(Sloc
(P
),
6682 Prefix
=> Relocate_Node
(P
));
6685 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
6689 -- If the selected component appears within a default expression
6690 -- and it has an actual subtype, the pre-analysis has not yet
6691 -- completed its analysis, because Insert_Actions is disabled in
6692 -- that context. Within the init proc of the enclosing type we
6693 -- must complete this analysis, if an actual subtype was created.
6695 elsif Inside_Init_Proc
then
6697 Typ
: constant Entity_Id
:= Etype
(N
);
6698 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
6700 if Nkind
(Decl
) = N_Subtype_Declaration
6701 and then not Analyzed
(Decl
)
6702 and then Is_List_Member
(Decl
)
6703 and then No
(Parent
(Decl
))
6706 Insert_Action
(N
, Decl
);
6713 elsif Is_Entity_Name
(P
) then
6714 P_Name
:= Entity
(P
);
6716 -- The prefix may denote an enclosing type which is the completion
6717 -- of an incomplete type declaration.
6719 if Is_Type
(P_Name
) then
6720 Set_Entity
(P
, Get_Full_View
(P_Name
));
6721 Set_Etype
(P
, Entity
(P
));
6722 P_Name
:= Entity
(P
);
6725 P_Type
:= Base_Type
(Etype
(P
));
6727 if Debug_Flag_E
then
6728 Write_Str
("Found prefix type to be ");
6729 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
6732 -- The designated type may be a limited view with no components.
6733 -- Check whether the non-limited view is available, because in some
6734 -- cases this will not be set when installing the context. Rewrite
6735 -- the node by introducing an explicit dereference at once, and
6736 -- setting the type of the rewritten prefix to the non-limited view
6737 -- of the original designated type.
6739 if Is_Access_Type
(P_Type
) then
6741 Desig_Typ
: constant Entity_Id
:=
6742 Directly_Designated_Type
(P_Type
);
6745 if Is_Incomplete_Type
(Desig_Typ
)
6746 and then From_Limited_With
(Desig_Typ
)
6747 and then Present
(Non_Limited_View
(Desig_Typ
))
6750 Make_Explicit_Dereference
(Sloc
(P
),
6751 Prefix
=> Relocate_Node
(P
)));
6753 Set_Etype
(P
, Get_Full_View
(Non_Limited_View
(Desig_Typ
)));
6754 P_Type
:= Etype
(P
);
6759 -- First check for components of a record object (not the
6760 -- result of a call, which is handled below).
6762 if Is_Appropriate_For_Record
(P_Type
)
6763 and then not Is_Overloadable
(P_Name
)
6764 and then not Is_Type
(P_Name
)
6766 -- Selected component of record. Type checking will validate
6767 -- name of selector.
6769 -- ??? Could we rewrite an implicit dereference into an explicit
6772 Analyze_Selected_Component
(N
);
6774 -- Reference to type name in predicate/invariant expression
6776 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
6777 and then not In_Open_Scopes
(P_Name
)
6778 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
6779 or else not In_Open_Scopes
(Etype
(P_Name
)))
6781 -- Call to protected operation or entry. Type checking is
6782 -- needed on the prefix.
6784 Analyze_Selected_Component
(N
);
6786 elsif (In_Open_Scopes
(P_Name
)
6787 and then Ekind
(P_Name
) /= E_Void
6788 and then not Is_Overloadable
(P_Name
))
6789 or else (Is_Concurrent_Type
(Etype
(P_Name
))
6790 and then In_Open_Scopes
(Etype
(P_Name
)))
6792 -- Prefix denotes an enclosing loop, block, or task, i.e. an
6793 -- enclosing construct that is not a subprogram or accept.
6795 -- A special case: a protected body may call an operation
6796 -- on an external object of the same type, in which case it
6797 -- is not an expanded name. If the prefix is the type itself,
6798 -- or the context is a single synchronized object it can only
6799 -- be interpreted as an expanded name.
6801 if Is_Concurrent_Type
(Etype
(P_Name
)) then
6803 or else Present
(Anonymous_Object
(Etype
(P_Name
)))
6805 Find_Expanded_Name
(N
);
6808 Analyze_Selected_Component
(N
);
6813 Find_Expanded_Name
(N
);
6816 elsif Ekind
(P_Name
) = E_Package
then
6817 Find_Expanded_Name
(N
);
6819 elsif Is_Overloadable
(P_Name
) then
6821 -- The subprogram may be a renaming (of an enclosing scope) as
6822 -- in the case of the name of the generic within an instantiation.
6824 if Ekind_In
(P_Name
, E_Procedure
, E_Function
)
6825 and then Present
(Alias
(P_Name
))
6826 and then Is_Generic_Instance
(Alias
(P_Name
))
6828 P_Name
:= Alias
(P_Name
);
6831 if Is_Overloaded
(P
) then
6833 -- The prefix must resolve to a unique enclosing construct
6836 Found
: Boolean := False;
6841 Get_First_Interp
(P
, Ind
, It
);
6842 while Present
(It
.Nam
) loop
6843 if In_Open_Scopes
(It
.Nam
) then
6846 "prefix must be unique enclosing scope", N
);
6847 Set_Entity
(N
, Any_Id
);
6848 Set_Etype
(N
, Any_Type
);
6857 Get_Next_Interp
(Ind
, It
);
6862 if In_Open_Scopes
(P_Name
) then
6863 Set_Entity
(P
, P_Name
);
6864 Set_Is_Overloaded
(P
, False);
6865 Find_Expanded_Name
(N
);
6868 -- If no interpretation as an expanded name is possible, it
6869 -- must be a selected component of a record returned by a
6870 -- function call. Reformat prefix as a function call, the rest
6871 -- is done by type resolution.
6873 -- Error if the prefix is procedure or entry, as is P.X
6875 if Ekind
(P_Name
) /= E_Function
6877 (not Is_Overloaded
(P
)
6878 or else Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
6880 -- Prefix may mention a package that is hidden by a local
6881 -- declaration: let the user know. Scan the full homonym
6882 -- chain, the candidate package may be anywhere on it.
6884 if Present
(Homonym
(Current_Entity
(P_Name
))) then
6885 P_Name
:= Current_Entity
(P_Name
);
6887 while Present
(P_Name
) loop
6888 exit when Ekind
(P_Name
) = E_Package
;
6889 P_Name
:= Homonym
(P_Name
);
6892 if Present
(P_Name
) then
6893 if not Is_Reference_In_Subunit
then
6894 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
6896 ("package& is hidden by declaration#", N
, P_Name
);
6899 Set_Entity
(Prefix
(N
), P_Name
);
6900 Find_Expanded_Name
(N
);
6904 P_Name
:= Entity
(Prefix
(N
));
6909 ("invalid prefix in selected component&", N
, P_Name
);
6910 Change_Selected_Component_To_Expanded_Name
(N
);
6911 Set_Entity
(N
, Any_Id
);
6912 Set_Etype
(N
, Any_Type
);
6914 -- Here we have a function call, so do the reformatting
6917 Nam
:= New_Copy
(P
);
6918 Save_Interps
(P
, Nam
);
6920 -- We use Replace here because this is one of those cases
6921 -- where the parser has missclassified the node, and we
6922 -- fix things up and then do the semantic analysis on the
6923 -- fixed up node. Normally we do this using one of the
6924 -- Sinfo.CN routines, but this is too tricky for that.
6926 -- Note that using Rewrite would be wrong, because we
6927 -- would have a tree where the original node is unanalyzed,
6928 -- and this violates the required interface for ASIS.
6931 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
6933 -- Now analyze the reformatted node
6936 Analyze_Selected_Component
(N
);
6940 -- Remaining cases generate various error messages
6943 -- Format node as expanded name, to avoid cascaded errors
6945 -- If the limited_with transformation was applied earlier,
6946 -- restore source for proper error reporting.
6948 if not Comes_From_Source
(P
)
6949 and then Nkind
(P
) = N_Explicit_Dereference
6951 Rewrite
(P
, Prefix
(P
));
6952 P_Type
:= Etype
(P
);
6955 Change_Selected_Component_To_Expanded_Name
(N
);
6956 Set_Entity
(N
, Any_Id
);
6957 Set_Etype
(N
, Any_Type
);
6959 -- Issue error message, but avoid this if error issued already.
6960 -- Use identifier of prefix if one is available.
6962 if P_Name
= Any_Id
then
6965 -- It is not an error if the prefix is the current instance of
6966 -- type name, e.g. the expression of a type aspect, when it is
6967 -- analyzed for ASIS use.
6969 elsif Is_Entity_Name
(P
) and then Is_Current_Instance
(P
) then
6972 elsif Ekind
(P_Name
) = E_Void
then
6973 Premature_Usage
(P
);
6975 elsif Nkind
(P
) /= N_Attribute_Reference
then
6977 -- This may have been meant as a prefixed call to a primitive
6978 -- of an untagged type.
6981 F
: constant Entity_Id
:=
6982 Current_Entity
(Selector_Name
(N
));
6985 and then Is_Overloadable
(F
)
6986 and then Present
(First_Entity
(F
))
6987 and then Etype
(First_Entity
(F
)) = Etype
(P
)
6988 and then not Is_Tagged_Type
(Etype
(P
))
6991 ("prefixed call is only allowed for objects "
6992 & "of a tagged type", N
);
6996 Error_Msg_N
("invalid prefix in selected component&", P
);
6998 if Is_Access_Type
(P_Type
)
6999 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
7002 ("\dereference must not be of an incomplete type "
7003 & "(RM 3.10.1)", P
);
7007 Error_Msg_N
("invalid prefix in selected component", P
);
7011 -- Selector name is restricted in SPARK
7013 if Nkind
(N
) = N_Expanded_Name
7014 and then Restriction_Check_Required
(SPARK_05
)
7016 if Is_Subprogram
(P_Name
) then
7017 Check_SPARK_05_Restriction
7018 ("prefix of expanded name cannot be a subprogram", P
);
7019 elsif Ekind
(P_Name
) = E_Loop
then
7020 Check_SPARK_05_Restriction
7021 ("prefix of expanded name cannot be a loop statement", P
);
7026 -- If prefix is not the name of an entity, it must be an expression,
7027 -- whose type is appropriate for a record. This is determined by
7030 Analyze_Selected_Component
(N
);
7033 Analyze_Dimension
(N
);
7034 end Find_Selected_Component
;
7040 procedure Find_Type
(N
: Node_Id
) is
7050 elsif Nkind
(N
) = N_Attribute_Reference
then
7052 -- Class attribute. This is not valid in Ada 83 mode, but we do not
7053 -- need to enforce that at this point, since the declaration of the
7054 -- tagged type in the prefix would have been flagged already.
7056 if Attribute_Name
(N
) = Name_Class
then
7057 Check_Restriction
(No_Dispatch
, N
);
7058 Find_Type
(Prefix
(N
));
7060 -- Propagate error from bad prefix
7062 if Etype
(Prefix
(N
)) = Any_Type
then
7063 Set_Entity
(N
, Any_Type
);
7064 Set_Etype
(N
, Any_Type
);
7068 T
:= Base_Type
(Entity
(Prefix
(N
)));
7070 -- Case where type is not known to be tagged. Its appearance in
7071 -- the prefix of the 'Class attribute indicates that the full view
7074 if not Is_Tagged_Type
(T
) then
7075 if Ekind
(T
) = E_Incomplete_Type
then
7077 -- It is legal to denote the class type of an incomplete
7078 -- type. The full type will have to be tagged, of course.
7079 -- In Ada 2005 this usage is declared obsolescent, so we
7080 -- warn accordingly. This usage is only legal if the type
7081 -- is completed in the current scope, and not for a limited
7084 if Ada_Version
>= Ada_2005
then
7086 -- Test whether the Available_View of a limited type view
7087 -- is tagged, since the limited view may not be marked as
7088 -- tagged if the type itself has an untagged incomplete
7089 -- type view in its package.
7091 if From_Limited_With
(T
)
7092 and then not Is_Tagged_Type
(Available_View
(T
))
7095 ("prefix of Class attribute must be tagged", N
);
7096 Set_Etype
(N
, Any_Type
);
7097 Set_Entity
(N
, Any_Type
);
7100 -- ??? This test is temporarily disabled (always
7101 -- False) because it causes an unwanted warning on
7102 -- GNAT sources (built with -gnatg, which includes
7103 -- Warn_On_Obsolescent_ Feature). Once this issue
7104 -- is cleared in the sources, it can be enabled.
7106 elsif Warn_On_Obsolescent_Feature
and then False then
7108 ("applying 'Class to an untagged incomplete type"
7109 & " is an obsolescent feature (RM J.11)?r?", N
);
7113 Set_Is_Tagged_Type
(T
);
7114 Set_Direct_Primitive_Operations
(T
, New_Elmt_List
);
7115 Make_Class_Wide_Type
(T
);
7116 Set_Entity
(N
, Class_Wide_Type
(T
));
7117 Set_Etype
(N
, Class_Wide_Type
(T
));
7119 elsif Ekind
(T
) = E_Private_Type
7120 and then not Is_Generic_Type
(T
)
7121 and then In_Private_Part
(Scope
(T
))
7123 -- The Class attribute can be applied to an untagged private
7124 -- type fulfilled by a tagged type prior to the full type
7125 -- declaration (but only within the parent package's private
7126 -- part). Create the class-wide type now and check that the
7127 -- full type is tagged later during its analysis. Note that
7128 -- we do not mark the private type as tagged, unlike the
7129 -- case of incomplete types, because the type must still
7130 -- appear untagged to outside units.
7132 if No
(Class_Wide_Type
(T
)) then
7133 Make_Class_Wide_Type
(T
);
7136 Set_Entity
(N
, Class_Wide_Type
(T
));
7137 Set_Etype
(N
, Class_Wide_Type
(T
));
7140 -- Should we introduce a type Any_Tagged and use Wrong_Type
7141 -- here, it would be a bit more consistent???
7144 ("tagged type required, found}",
7145 Prefix
(N
), First_Subtype
(T
));
7146 Set_Entity
(N
, Any_Type
);
7150 -- Case of tagged type
7153 if Is_Concurrent_Type
(T
) then
7154 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
7156 -- Previous error. Use current type, which at least
7157 -- provides some operations.
7159 C
:= Entity
(Prefix
(N
));
7162 C
:= Class_Wide_Type
7163 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
7167 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
7170 Set_Entity_With_Checks
(N
, C
);
7171 Generate_Reference
(C
, N
);
7175 -- Base attribute, not allowed in Ada 83
7177 elsif Attribute_Name
(N
) = Name_Base
then
7178 Error_Msg_Name_1
:= Name_Base
;
7179 Check_SPARK_05_Restriction
7180 ("attribute% is only allowed as prefix of another attribute", N
);
7182 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
7184 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
7187 Find_Type
(Prefix
(N
));
7188 Typ
:= Entity
(Prefix
(N
));
7190 if Ada_Version
>= Ada_95
7191 and then not Is_Scalar_Type
(Typ
)
7192 and then not Is_Generic_Type
(Typ
)
7195 ("prefix of Base attribute must be scalar type",
7198 elsif Warn_On_Redundant_Constructs
7199 and then Base_Type
(Typ
) = Typ
7201 Error_Msg_NE
-- CODEFIX
7202 ("redundant attribute, & is its own base type?r?", N
, Typ
);
7205 T
:= Base_Type
(Typ
);
7207 -- Rewrite attribute reference with type itself (see similar
7208 -- processing in Analyze_Attribute, case Base). Preserve prefix
7209 -- if present, for other legality checks.
7211 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
7213 Make_Expanded_Name
(Sloc
(N
),
7215 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
7216 Selector_Name
=> New_Occurrence_Of
(T
, Sloc
(N
))));
7219 Rewrite
(N
, New_Occurrence_Of
(T
, Sloc
(N
)));
7226 elsif Attribute_Name
(N
) = Name_Stub_Type
then
7228 -- This is handled in Analyze_Attribute
7232 -- All other attributes are invalid in a subtype mark
7235 Error_Msg_N
("invalid attribute in subtype mark", N
);
7241 if Is_Entity_Name
(N
) then
7242 T_Name
:= Entity
(N
);
7244 Error_Msg_N
("subtype mark required in this context", N
);
7245 Set_Etype
(N
, Any_Type
);
7249 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
7251 -- Undefined id. Make it into a valid type
7253 Set_Entity
(N
, Any_Type
);
7255 elsif not Is_Type
(T_Name
)
7256 and then T_Name
/= Standard_Void_Type
7258 Error_Msg_Sloc
:= Sloc
(T_Name
);
7259 Error_Msg_N
("subtype mark required in this context", N
);
7260 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
7261 Set_Entity
(N
, Any_Type
);
7264 -- If the type is an incomplete type created to handle
7265 -- anonymous access components of a record type, then the
7266 -- incomplete type is the visible entity and subsequent
7267 -- references will point to it. Mark the original full
7268 -- type as referenced, to prevent spurious warnings.
7270 if Is_Incomplete_Type
(T_Name
)
7271 and then Present
(Full_View
(T_Name
))
7272 and then not Comes_From_Source
(T_Name
)
7274 Set_Referenced
(Full_View
(T_Name
));
7277 T_Name
:= Get_Full_View
(T_Name
);
7279 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
7280 -- limited-with clauses
7282 if From_Limited_With
(T_Name
)
7283 and then Ekind
(T_Name
) in Incomplete_Kind
7284 and then Present
(Non_Limited_View
(T_Name
))
7285 and then Is_Interface
(Non_Limited_View
(T_Name
))
7287 T_Name
:= Non_Limited_View
(T_Name
);
7290 if In_Open_Scopes
(T_Name
) then
7291 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
7293 -- In Ada 2005, a task name can be used in an access
7294 -- definition within its own body. It cannot be used
7295 -- in the discriminant part of the task declaration,
7296 -- nor anywhere else in the declaration because entries
7297 -- cannot have access parameters.
7299 if Ada_Version
>= Ada_2005
7300 and then Nkind
(Parent
(N
)) = N_Access_Definition
7302 Set_Entity
(N
, T_Name
);
7303 Set_Etype
(N
, T_Name
);
7305 if Has_Completion
(T_Name
) then
7310 ("task type cannot be used as type mark " &
7311 "within its own declaration", N
);
7316 ("task type cannot be used as type mark " &
7317 "within its own spec or body", N
);
7320 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
7322 -- In Ada 2005, a protected name can be used in an access
7323 -- definition within its own body.
7325 if Ada_Version
>= Ada_2005
7326 and then Nkind
(Parent
(N
)) = N_Access_Definition
7328 Set_Entity
(N
, T_Name
);
7329 Set_Etype
(N
, T_Name
);
7334 ("protected type cannot be used as type mark " &
7335 "within its own spec or body", N
);
7339 Error_Msg_N
("type declaration cannot refer to itself", N
);
7342 Set_Etype
(N
, Any_Type
);
7343 Set_Entity
(N
, Any_Type
);
7344 Set_Error_Posted
(T_Name
);
7348 Set_Entity
(N
, T_Name
);
7349 Set_Etype
(N
, T_Name
);
7353 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
7354 if Is_Fixed_Point_Type
(Etype
(N
)) then
7355 Check_Restriction
(No_Fixed_Point
, N
);
7356 elsif Is_Floating_Point_Type
(Etype
(N
)) then
7357 Check_Restriction
(No_Floating_Point
, N
);
7360 -- A Ghost type must appear in a specific context
7362 if Is_Ghost_Entity
(Etype
(N
)) then
7363 Check_Ghost_Context
(Etype
(N
), N
);
7368 ------------------------------------
7369 -- Has_Implicit_Character_Literal --
7370 ------------------------------------
7372 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
7374 Found
: Boolean := False;
7375 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7376 Priv_Id
: Entity_Id
:= Empty
;
7379 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7380 Priv_Id
:= First_Private_Entity
(P
);
7383 if P
= Standard_Standard
then
7384 Change_Selected_Component_To_Expanded_Name
(N
);
7385 Rewrite
(N
, Selector_Name
(N
));
7387 Set_Etype
(Original_Node
(N
), Standard_Character
);
7391 Id
:= First_Entity
(P
);
7392 while Present
(Id
) and then Id
/= Priv_Id
loop
7393 if Is_Standard_Character_Type
(Id
) and then Is_Base_Type
(Id
) then
7395 -- We replace the node with the literal itself, resolve as a
7396 -- character, and set the type correctly.
7399 Change_Selected_Component_To_Expanded_Name
(N
);
7400 Rewrite
(N
, Selector_Name
(N
));
7403 Set_Etype
(Original_Node
(N
), Id
);
7407 -- More than one type derived from Character in given scope.
7408 -- Collect all possible interpretations.
7410 Add_One_Interp
(N
, Id
, Id
);
7418 end Has_Implicit_Character_Literal
;
7420 ----------------------
7421 -- Has_Private_With --
7422 ----------------------
7424 function Has_Private_With
(E
: Entity_Id
) return Boolean is
7425 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
7429 Item
:= First
(Context_Items
(Comp_Unit
));
7430 while Present
(Item
) loop
7431 if Nkind
(Item
) = N_With_Clause
7432 and then Private_Present
(Item
)
7433 and then Entity
(Name
(Item
)) = E
7442 end Has_Private_With
;
7444 ---------------------------
7445 -- Has_Implicit_Operator --
7446 ---------------------------
7448 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
7449 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
7450 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
7452 Priv_Id
: Entity_Id
:= Empty
;
7454 procedure Add_Implicit_Operator
7456 Op_Type
: Entity_Id
:= Empty
);
7457 -- Add implicit interpretation to node N, using the type for which a
7458 -- predefined operator exists. If the operator yields a boolean type,
7459 -- the Operand_Type is implicitly referenced by the operator, and a
7460 -- reference to it must be generated.
7462 ---------------------------
7463 -- Add_Implicit_Operator --
7464 ---------------------------
7466 procedure Add_Implicit_Operator
7468 Op_Type
: Entity_Id
:= Empty
)
7470 Predef_Op
: Entity_Id
;
7473 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
7474 while Present
(Predef_Op
)
7475 and then Scope
(Predef_Op
) /= Standard_Standard
7477 Predef_Op
:= Homonym
(Predef_Op
);
7480 if Nkind
(N
) = N_Selected_Component
then
7481 Change_Selected_Component_To_Expanded_Name
(N
);
7484 -- If the context is an unanalyzed function call, determine whether
7485 -- a binary or unary interpretation is required.
7487 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
7489 Is_Binary_Call
: constant Boolean :=
7491 (Next
(First
(Expressions
(Parent
(N
)))));
7492 Is_Binary_Op
: constant Boolean :=
7494 (Predef_Op
) /= Last_Entity
(Predef_Op
);
7495 Predef_Op2
: constant Entity_Id
:= Homonym
(Predef_Op
);
7498 if Is_Binary_Call
then
7499 if Is_Binary_Op
then
7500 Add_One_Interp
(N
, Predef_Op
, T
);
7502 Add_One_Interp
(N
, Predef_Op2
, T
);
7506 if not Is_Binary_Op
then
7507 Add_One_Interp
(N
, Predef_Op
, T
);
7509 Add_One_Interp
(N
, Predef_Op2
, T
);
7515 Add_One_Interp
(N
, Predef_Op
, T
);
7517 -- For operators with unary and binary interpretations, if
7518 -- context is not a call, add both
7520 if Present
(Homonym
(Predef_Op
)) then
7521 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
7525 -- The node is a reference to a predefined operator, and
7526 -- an implicit reference to the type of its operands.
7528 if Present
(Op_Type
) then
7529 Generate_Operator_Reference
(N
, Op_Type
);
7531 Generate_Operator_Reference
(N
, T
);
7533 end Add_Implicit_Operator
;
7535 -- Start of processing for Has_Implicit_Operator
7538 if Ekind
(P
) = E_Package
and then not In_Open_Scopes
(P
) then
7539 Priv_Id
:= First_Private_Entity
(P
);
7542 Id
:= First_Entity
(P
);
7546 -- Boolean operators: an implicit declaration exists if the scope
7547 -- contains a declaration for a derived Boolean type, or for an
7548 -- array of Boolean type.
7550 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
7551 while Id
/= Priv_Id
loop
7552 if Valid_Boolean_Arg
(Id
) and then Is_Base_Type
(Id
) then
7553 Add_Implicit_Operator
(Id
);
7560 -- Equality: look for any non-limited type (result is Boolean)
7562 when Name_Op_Eq | Name_Op_Ne
=>
7563 while Id
/= Priv_Id
loop
7565 and then not Is_Limited_Type
(Id
)
7566 and then Is_Base_Type
(Id
)
7568 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7575 -- Comparison operators: scalar type, or array of scalar
7577 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
7578 while Id
/= Priv_Id
loop
7579 if (Is_Scalar_Type
(Id
)
7580 or else (Is_Array_Type
(Id
)
7581 and then Is_Scalar_Type
(Component_Type
(Id
))))
7582 and then Is_Base_Type
(Id
)
7584 Add_Implicit_Operator
(Standard_Boolean
, Id
);
7591 -- Arithmetic operators: any numeric type
7601 while Id
/= Priv_Id
loop
7602 if Is_Numeric_Type
(Id
) and then Is_Base_Type
(Id
) then
7603 Add_Implicit_Operator
(Id
);
7610 -- Concatenation: any one-dimensional array type
7612 when Name_Op_Concat
=>
7613 while Id
/= Priv_Id
loop
7614 if Is_Array_Type
(Id
)
7615 and then Number_Dimensions
(Id
) = 1
7616 and then Is_Base_Type
(Id
)
7618 Add_Implicit_Operator
(Id
);
7625 -- What is the others condition here? Should we be using a
7626 -- subtype of Name_Id that would restrict to operators ???
7628 when others => null;
7631 -- If we fall through, then we do not have an implicit operator
7635 end Has_Implicit_Operator
;
7637 -----------------------------------
7638 -- Has_Loop_In_Inner_Open_Scopes --
7639 -----------------------------------
7641 function Has_Loop_In_Inner_Open_Scopes
(S
: Entity_Id
) return Boolean is
7643 -- Several scope stacks are maintained by Scope_Stack. The base of the
7644 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7645 -- flag in the scope stack entry. Note that the scope stacks used to
7646 -- simply be delimited implicitly by the presence of Standard_Standard
7647 -- at their base, but there now are cases where this is not sufficient
7648 -- because Standard_Standard actually may appear in the middle of the
7649 -- active set of scopes.
7651 for J
in reverse 0 .. Scope_Stack
.Last
loop
7653 -- S was reached without seing a loop scope first
7655 if Scope_Stack
.Table
(J
).Entity
= S
then
7658 -- S was not yet reached, so it contains at least one inner loop
7660 elsif Ekind
(Scope_Stack
.Table
(J
).Entity
) = E_Loop
then
7664 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7665 -- cases where Standard_Standard appears in the middle of the active
7666 -- set of scopes. This affects the declaration and overriding of
7667 -- private inherited operations in instantiations of generic child
7670 pragma Assert
(not Scope_Stack
.Table
(J
).Is_Active_Stack_Base
);
7673 raise Program_Error
; -- unreachable
7674 end Has_Loop_In_Inner_Open_Scopes
;
7676 --------------------
7677 -- In_Open_Scopes --
7678 --------------------
7680 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
7682 -- Several scope stacks are maintained by Scope_Stack. The base of the
7683 -- currently active scope stack is denoted by the Is_Active_Stack_Base
7684 -- flag in the scope stack entry. Note that the scope stacks used to
7685 -- simply be delimited implicitly by the presence of Standard_Standard
7686 -- at their base, but there now are cases where this is not sufficient
7687 -- because Standard_Standard actually may appear in the middle of the
7688 -- active set of scopes.
7690 for J
in reverse 0 .. Scope_Stack
.Last
loop
7691 if Scope_Stack
.Table
(J
).Entity
= S
then
7695 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
7696 -- cases where Standard_Standard appears in the middle of the active
7697 -- set of scopes. This affects the declaration and overriding of
7698 -- private inherited operations in instantiations of generic child
7701 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
7707 -----------------------------
7708 -- Inherit_Renamed_Profile --
7709 -----------------------------
7711 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
7718 if Ekind
(Old_S
) = E_Operator
then
7719 New_F
:= First_Formal
(New_S
);
7721 while Present
(New_F
) loop
7722 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
7723 Next_Formal
(New_F
);
7726 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
7729 New_F
:= First_Formal
(New_S
);
7730 Old_F
:= First_Formal
(Old_S
);
7732 while Present
(New_F
) loop
7733 New_T
:= Etype
(New_F
);
7734 Old_T
:= Etype
(Old_F
);
7736 -- If the new type is a renaming of the old one, as is the
7737 -- case for actuals in instances, retain its name, to simplify
7738 -- later disambiguation.
7740 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
7741 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
7742 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
7746 Set_Etype
(New_F
, Old_T
);
7749 Next_Formal
(New_F
);
7750 Next_Formal
(Old_F
);
7753 if Ekind_In
(Old_S
, E_Function
, E_Enumeration_Literal
) then
7754 Set_Etype
(New_S
, Etype
(Old_S
));
7757 end Inherit_Renamed_Profile
;
7763 procedure Initialize
is
7768 -------------------------
7769 -- Install_Use_Clauses --
7770 -------------------------
7772 procedure Install_Use_Clauses
7774 Force_Installation
: Boolean := False)
7782 while Present
(U
) loop
7784 -- Case of USE package
7786 if Nkind
(U
) = N_Use_Package_Clause
then
7787 P
:= First
(Names
(U
));
7788 while Present
(P
) loop
7791 if Ekind
(Id
) = E_Package
then
7793 Note_Redundant_Use
(P
);
7795 elsif Present
(Renamed_Object
(Id
))
7796 and then In_Use
(Renamed_Object
(Id
))
7798 Note_Redundant_Use
(P
);
7800 elsif Force_Installation
or else Applicable_Use
(P
) then
7801 Use_One_Package
(Id
, U
);
7812 P
:= First
(Subtype_Marks
(U
));
7813 while Present
(P
) loop
7814 if not Is_Entity_Name
(P
)
7815 or else No
(Entity
(P
))
7819 elsif Entity
(P
) /= Any_Type
then
7827 Next_Use_Clause
(U
);
7829 end Install_Use_Clauses
;
7831 -------------------------------------
7832 -- Is_Appropriate_For_Entry_Prefix --
7833 -------------------------------------
7835 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
7836 P_Type
: Entity_Id
:= T
;
7839 if Is_Access_Type
(P_Type
) then
7840 P_Type
:= Designated_Type
(P_Type
);
7843 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
7844 end Is_Appropriate_For_Entry_Prefix
;
7846 -------------------------------
7847 -- Is_Appropriate_For_Record --
7848 -------------------------------
7850 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
7852 function Has_Components
(T1
: Entity_Id
) return Boolean;
7853 -- Determine if given type has components (i.e. is either a record
7854 -- type or a type that has discriminants).
7856 --------------------
7857 -- Has_Components --
7858 --------------------
7860 function Has_Components
(T1
: Entity_Id
) return Boolean is
7862 return Is_Record_Type
(T1
)
7863 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
7864 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
7865 or else (Is_Incomplete_Type
(T1
)
7866 and then From_Limited_With
(T1
)
7867 and then Present
(Non_Limited_View
(T1
))
7868 and then Is_Record_Type
7869 (Get_Full_View
(Non_Limited_View
(T1
))));
7872 -- Start of processing for Is_Appropriate_For_Record
7877 and then (Has_Components
(T
)
7878 or else (Is_Access_Type
(T
)
7879 and then Has_Components
(Designated_Type
(T
))));
7880 end Is_Appropriate_For_Record
;
7882 ------------------------
7883 -- Note_Redundant_Use --
7884 ------------------------
7886 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
7887 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
7888 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
7889 Decl
: constant Node_Id
:= Parent
(Clause
);
7891 Prev_Use
: Node_Id
:= Empty
;
7892 Redundant
: Node_Id
:= Empty
;
7893 -- The Use_Clause which is actually redundant. In the simplest case it
7894 -- is Pack itself, but when we compile a body we install its context
7895 -- before that of its spec, in which case it is the use_clause in the
7896 -- spec that will appear to be redundant, and we want the warning to be
7897 -- placed on the body. Similar complications appear when the redundancy
7898 -- is between a child unit and one of its ancestors.
7901 Set_Redundant_Use
(Clause
, True);
7903 if not Comes_From_Source
(Clause
)
7905 or else not Warn_On_Redundant_Constructs
7910 if not Is_Compilation_Unit
(Current_Scope
) then
7912 -- If the use_clause is in an inner scope, it is made redundant by
7913 -- some clause in the current context, with one exception: If we're
7914 -- compiling a nested package body, and the use_clause comes from the
7915 -- corresponding spec, the clause is not necessarily fully redundant,
7916 -- so we should not warn. If a warning was warranted, it would have
7917 -- been given when the spec was processed.
7919 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
7921 Package_Spec_Entity
: constant Entity_Id
:=
7922 Defining_Unit_Name
(Parent
(Decl
));
7924 if In_Package_Body
(Package_Spec_Entity
) then
7930 Redundant
:= Clause
;
7931 Prev_Use
:= Cur_Use
;
7933 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
7935 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
7936 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
7940 if Cur_Unit
= New_Unit
then
7942 -- Redundant clause in same body
7944 Redundant
:= Clause
;
7945 Prev_Use
:= Cur_Use
;
7947 elsif Cur_Unit
= Current_Sem_Unit
then
7949 -- If the new clause is not in the current unit it has been
7950 -- analyzed first, and it makes the other one redundant.
7951 -- However, if the new clause appears in a subunit, Cur_Unit
7952 -- is still the parent, and in that case the redundant one
7953 -- is the one appearing in the subunit.
7955 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
7956 Redundant
:= Clause
;
7957 Prev_Use
:= Cur_Use
;
7959 -- Most common case: redundant clause in body,
7960 -- original clause in spec. Current scope is spec entity.
7965 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
7967 Redundant
:= Cur_Use
;
7971 -- The new clause may appear in an unrelated unit, when
7972 -- the parents of a generic are being installed prior to
7973 -- instantiation. In this case there must be no warning.
7974 -- We detect this case by checking whether the current top
7975 -- of the stack is related to the current compilation.
7977 Scop
:= Current_Scope
;
7978 while Present
(Scop
) and then Scop
/= Standard_Standard
loop
7979 if Is_Compilation_Unit
(Scop
)
7980 and then not Is_Child_Unit
(Scop
)
7984 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
7988 Scop
:= Scope
(Scop
);
7991 Redundant
:= Cur_Use
;
7995 elsif New_Unit
= Current_Sem_Unit
then
7996 Redundant
:= Clause
;
7997 Prev_Use
:= Cur_Use
;
8000 -- Neither is the current unit, so they appear in parent or
8001 -- sibling units. Warning will be emitted elsewhere.
8007 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
8008 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
8010 -- Use_clause is in child unit of current unit, and the child unit
8011 -- appears in the context of the body of the parent, so it has been
8012 -- installed first, even though it is the redundant one. Depending on
8013 -- their placement in the context, the visible or the private parts
8014 -- of the two units, either might appear as redundant, but the
8015 -- message has to be on the current unit.
8017 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
8018 Redundant
:= Cur_Use
;
8021 Redundant
:= Clause
;
8022 Prev_Use
:= Cur_Use
;
8025 -- If the new use clause appears in the private part of a parent unit
8026 -- it may appear to be redundant w.r.t. a use clause in a child unit,
8027 -- but the previous use clause was needed in the visible part of the
8028 -- child, and no warning should be emitted.
8030 if Nkind
(Parent
(Decl
)) = N_Package_Specification
8032 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
8035 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
8036 Spec
: constant Node_Id
:=
8037 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
8040 if Is_Compilation_Unit
(Par
)
8041 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
8042 and then Parent
(Cur_Use
) = Spec
8044 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
8051 -- Finally, if the current use clause is in the context then
8052 -- the clause is redundant when it is nested within the unit.
8054 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
8055 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
8056 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
8058 Redundant
:= Clause
;
8059 Prev_Use
:= Cur_Use
;
8065 if Present
(Redundant
) then
8066 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
8067 Error_Msg_NE
-- CODEFIX
8068 ("& is already use-visible through previous use clause #??",
8069 Redundant
, Pack_Name
);
8071 end Note_Redundant_Use
;
8077 procedure Pop_Scope
is
8078 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
8079 S
: constant Entity_Id
:= SST
.Entity
;
8082 if Debug_Flag_E
then
8086 -- Set Default_Storage_Pool field of the library unit if necessary
8088 if Ekind_In
(S
, E_Package
, E_Generic_Package
)
8090 Nkind
(Parent
(Unit_Declaration_Node
(S
))) = N_Compilation_Unit
8093 Aux
: constant Node_Id
:=
8094 Aux_Decls_Node
(Parent
(Unit_Declaration_Node
(S
)));
8096 if No
(Default_Storage_Pool
(Aux
)) then
8097 Set_Default_Storage_Pool
(Aux
, Default_Pool
);
8102 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
8103 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
8104 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
8105 Default_Pool
:= SST
.Save_Default_Storage_Pool
;
8106 No_Tagged_Streams
:= SST
.Save_No_Tagged_Streams
;
8107 SPARK_Mode
:= SST
.Save_SPARK_Mode
;
8108 SPARK_Mode_Pragma
:= SST
.Save_SPARK_Mode_Pragma
;
8109 Default_SSO
:= SST
.Save_Default_SSO
;
8110 Uneval_Old
:= SST
.Save_Uneval_Old
;
8112 if Debug_Flag_W
then
8113 Write_Str
("<-- exiting scope: ");
8114 Write_Name
(Chars
(Current_Scope
));
8115 Write_Str
(", Depth=");
8116 Write_Int
(Int
(Scope_Stack
.Last
));
8120 End_Use_Clauses
(SST
.First_Use_Clause
);
8122 -- If the actions to be wrapped are still there they will get lost
8123 -- causing incomplete code to be generated. It is better to abort in
8124 -- this case (and we do the abort even with assertions off since the
8125 -- penalty is incorrect code generation).
8127 if SST
.Actions_To_Be_Wrapped
/= Scope_Actions
'(others => No_List) then
8128 raise Program_Error;
8131 -- Free last subprogram name if allocated, and pop scope
8133 Free (SST.Last_Subprogram_Name);
8134 Scope_Stack.Decrement_Last;
8141 procedure Push_Scope (S : Entity_Id) is
8142 E : constant Entity_Id := Scope (S);
8145 if Ekind (S) = E_Void then
8148 -- Set scope depth if not a non-concurrent type, and we have not yet set
8149 -- the scope depth. This means that we have the first occurrence of the
8150 -- scope, and this is where the depth is set.
8152 elsif (not Is_Type (S) or else Is_Concurrent_Type (S))
8153 and then not Scope_Depth_Set (S)
8155 if S = Standard_Standard then
8156 Set_Scope_Depth_Value (S, Uint_0);
8158 elsif Is_Child_Unit (S) then
8159 Set_Scope_Depth_Value (S, Uint_1);
8161 elsif not Is_Record_Type (Current_Scope) then
8162 if Ekind (S) = E_Loop then
8163 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope));
8165 Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1);
8170 Scope_Stack.Increment_Last;
8173 SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
8177 SST.Save_Scope_Suppress := Scope_Suppress;
8178 SST.Save_Local_Suppress_Stack_Top := Local_Suppress_Stack_Top;
8179 SST.Save_Check_Policy_List := Check_Policy_List;
8180 SST.Save_Default_Storage_Pool := Default_Pool;
8181 SST.Save_No_Tagged_Streams := No_Tagged_Streams;
8182 SST.Save_SPARK_Mode := SPARK_Mode;
8183 SST.Save_SPARK_Mode_Pragma := SPARK_Mode_Pragma;
8184 SST.Save_Default_SSO := Default_SSO;
8185 SST.Save_Uneval_Old := Uneval_Old;
8187 if Scope_Stack.Last > Scope_Stack.First then
8188 SST.Component_Alignment_Default := Scope_Stack.Table
8189 (Scope_Stack.Last - 1).
8190 Component_Alignment_Default;
8193 SST.Last_Subprogram_Name := null;
8194 SST.Is_Transient := False;
8195 SST.Node_To_Be_Wrapped := Empty;
8196 SST.Pending_Freeze_Actions := No_List;
8197 SST.Actions_To_Be_Wrapped := (others => No_List);
8198 SST.First_Use_Clause := Empty;
8199 SST.Is_Active_Stack_Base := False;
8200 SST.Previous_Visibility := False;
8201 SST.Locked_Shared_Objects := No_Elist;
8204 if Debug_Flag_W then
8205 Write_Str ("--> new scope: ");
8206 Write_Name (Chars (Current_Scope));
8207 Write_Str (", Id=");
8208 Write_Int (Int (Current_Scope));
8209 Write_Str (", Depth=");
8210 Write_Int (Int (Scope_Stack.Last));
8214 -- Deal with copying flags from the previous scope to this one. This is
8215 -- not necessary if either scope is standard, or if the new scope is a
8218 if S /= Standard_Standard
8219 and then Scope (S) /= Standard_Standard
8220 and then not Is_Child_Unit (S)
8222 if Nkind (E) not in N_Entity then
8226 -- Copy categorization flags from Scope (S) to S, this is not done
8227 -- when Scope (S) is Standard_Standard since propagation is from
8228 -- library unit entity inwards. Copy other relevant attributes as
8229 -- well (Discard_Names in particular).
8231 -- We only propagate inwards for library level entities,
8232 -- inner level subprograms do not inherit the categorization.
8234 if Is_Library_Level_Entity (S) then
8235 Set_Is_Preelaborated (S, Is_Preelaborated (E));
8236 Set_Is_Shared_Passive (S, Is_Shared_Passive (E));
8237 Set_Discard_Names (S, Discard_Names (E));
8238 Set_Suppress_Value_Tracking_On_Call
8239 (S, Suppress_Value_Tracking_On_Call (E));
8240 Set_Categorization_From_Scope (E => S, Scop => E);
8244 if Is_Child_Unit (S)
8245 and then Present (E)
8246 and then Ekind_In (E, E_Package, E_Generic_Package)
8248 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8251 Aux : constant Node_Id :=
8252 Aux_Decls_Node (Parent (Unit_Declaration_Node (E)));
8254 if Present (Default_Storage_Pool (Aux)) then
8255 Default_Pool := Default_Storage_Pool (Aux);
8261 ---------------------
8262 -- Premature_Usage --
8263 ---------------------
8265 procedure Premature_Usage (N : Node_Id) is
8266 Kind : constant Node_Kind := Nkind (Parent (Entity (N)));
8267 E : Entity_Id := Entity (N);
8270 -- Within an instance, the analysis of the actual for a formal object
8271 -- does not see the name of the object itself. This is significant only
8272 -- if the object is an aggregate, where its analysis does not do any
8273 -- name resolution on component associations. (see 4717-008). In such a
8274 -- case, look for the visible homonym on the chain.
8276 if In_Instance and then Present (Homonym (E)) then
8278 while Present (E) and then not In_Open_Scopes (Scope (E)) loop
8284 Set_Etype (N, Etype (E));
8289 if Kind = N_Component_Declaration then
8291 ("component&! cannot be used before end of record declaration", N);
8293 elsif Kind = N_Parameter_Specification then
8295 ("formal parameter&! cannot be used before end of specification",
8298 elsif Kind = N_Discriminant_Specification then
8300 ("discriminant&! cannot be used before end of discriminant part",
8303 elsif Kind = N_Procedure_Specification
8304 or else Kind = N_Function_Specification
8307 ("subprogram&! cannot be used before end of its declaration",
8310 elsif Kind = N_Full_Type_Declaration then
8312 ("type& cannot be used before end of its declaration!", N);
8316 ("object& cannot be used before end of its declaration!", N);
8318 end Premature_Usage;
8320 ------------------------
8321 -- Present_System_Aux --
8322 ------------------------
8324 function Present_System_Aux (N : Node_Id := Empty) return Boolean is
8326 Aux_Name : Unit_Name_Type;
8327 Unum : Unit_Number_Type;
8332 function Find_System (C_Unit : Node_Id) return Entity_Id;
8333 -- Scan context clause of compilation unit to find with_clause
8340 function Find_System (C_Unit : Node_Id) return Entity_Id is
8341 With_Clause : Node_Id;
8344 With_Clause := First (Context_Items (C_Unit));
8345 while Present (With_Clause) loop
8346 if (Nkind (With_Clause) = N_With_Clause
8347 and then Chars (Name (With_Clause)) = Name_System)
8348 and then Comes_From_Source (With_Clause)
8359 -- Start of processing for Present_System_Aux
8362 -- The child unit may have been loaded and analyzed already
8364 if Present (System_Aux_Id) then
8367 -- If no previous pragma for System.Aux, nothing to load
8369 elsif No (System_Extend_Unit) then
8372 -- Use the unit name given in the pragma to retrieve the unit.
8373 -- Verify that System itself appears in the context clause of the
8374 -- current compilation. If System is not present, an error will
8375 -- have been reported already.
8378 With_Sys := Find_System (Cunit (Current_Sem_Unit));
8380 The_Unit := Unit (Cunit (Current_Sem_Unit));
8384 (Nkind (The_Unit) = N_Package_Body
8385 or else (Nkind (The_Unit) = N_Subprogram_Body
8386 and then not Acts_As_Spec (Cunit (Current_Sem_Unit))))
8388 With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit)));
8391 if No (With_Sys) and then Present (N) then
8393 -- If we are compiling a subunit, we need to examine its
8394 -- context as well (Current_Sem_Unit is the parent unit);
8396 The_Unit := Parent (N);
8397 while Nkind (The_Unit) /= N_Compilation_Unit loop
8398 The_Unit := Parent (The_Unit);
8401 if Nkind (Unit (The_Unit)) = N_Subunit then
8402 With_Sys := Find_System (The_Unit);
8406 if No (With_Sys) then
8410 Loc := Sloc (With_Sys);
8411 Get_Name_String (Chars (Expression (System_Extend_Unit)));
8412 Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
8413 Name_Buffer (1 .. 7) := "system.";
8414 Name_Buffer (Name_Len + 8) := '%';
8415 Name_Buffer (Name_Len + 9) := 's
';
8416 Name_Len := Name_Len + 9;
8417 Aux_Name := Name_Find;
8421 (Load_Name => Aux_Name,
8424 Error_Node => With_Sys);
8426 if Unum /= No_Unit then
8427 Semantics (Cunit (Unum));
8429 Defining_Entity (Specification (Unit (Cunit (Unum))));
8432 Make_With_Clause (Loc,
8434 Make_Expanded_Name (Loc,
8435 Chars => Chars (System_Aux_Id),
8436 Prefix => New_Occurrence_Of (Scope (System_Aux_Id), Loc),
8437 Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc)));
8439 Set_Entity (Name (Withn), System_Aux_Id);
8441 Set_Library_Unit (Withn, Cunit (Unum));
8442 Set_Corresponding_Spec (Withn, System_Aux_Id);
8443 Set_First_Name (Withn, True);
8444 Set_Implicit_With (Withn, True);
8446 Insert_After (With_Sys, Withn);
8447 Mark_Rewrite_Insertion (Withn);
8448 Set_Context_Installed (Withn);
8452 -- Here if unit load failed
8455 Error_Msg_Name_1 := Name_System;
8456 Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit));
8458 ("extension package `%.%` does not exist",
8459 Opt.System_Extend_Unit);
8463 end Present_System_Aux;
8465 -------------------------
8466 -- Restore_Scope_Stack --
8467 -------------------------
8469 procedure Restore_Scope_Stack
8471 Handle_Use : Boolean := True)
8473 SS_Last : constant Int := Scope_Stack.Last;
8477 -- Restore visibility of previous scope stack, if any, using the list
8478 -- we saved (we use Remove, since this list will not be used again).
8481 Elmt := Last_Elmt (List);
8482 exit when Elmt = No_Elmt;
8483 Set_Is_Immediately_Visible (Node (Elmt));
8484 Remove_Last_Elmt (List);
8487 -- Restore use clauses
8489 if SS_Last >= Scope_Stack.First
8490 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8493 Install_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8495 end Restore_Scope_Stack;
8497 ----------------------
8498 -- Save_Scope_Stack --
8499 ----------------------
8501 -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid
8502 -- consuming any memory. That is, Save_Scope_Stack took care of removing
8503 -- from immediate visibility entities and Restore_Scope_Stack took care
8504 -- of restoring their visibility analyzing the context of each entity. The
8505 -- problem of such approach is that it was fragile and caused unexpected
8506 -- visibility problems, and indeed one test was found where there was a
8509 -- Furthermore, the following experiment was carried out:
8511 -- - Save_Scope_Stack was modified to store in an Elist1 all those
8512 -- entities whose attribute Is_Immediately_Visible is modified
8513 -- from True to False.
8515 -- - Restore_Scope_Stack was modified to store in another Elist2
8516 -- all the entities whose attribute Is_Immediately_Visible is
8517 -- modified from False to True.
8519 -- - Extra code was added to verify that all the elements of Elist1
8520 -- are found in Elist2
8522 -- This test shows that there may be more occurrences of this problem which
8523 -- have not yet been detected. As a result, we replaced that approach by
8524 -- the current one in which Save_Scope_Stack returns the list of entities
8525 -- whose visibility is changed, and that list is passed to Restore_Scope_
8526 -- Stack to undo that change. This approach is simpler and safer, although
8527 -- it consumes more memory.
8529 function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is
8530 Result : constant Elist_Id := New_Elmt_List;
8533 SS_Last : constant Int := Scope_Stack.Last;
8535 procedure Remove_From_Visibility (E : Entity_Id);
8536 -- If E is immediately visible then append it to the result and remove
8537 -- it temporarily from visibility.
8539 ----------------------------
8540 -- Remove_From_Visibility --
8541 ----------------------------
8543 procedure Remove_From_Visibility (E : Entity_Id) is
8545 if Is_Immediately_Visible (E) then
8546 Append_Elmt (E, Result);
8547 Set_Is_Immediately_Visible (E, False);
8549 end Remove_From_Visibility;
8551 -- Start of processing for Save_Scope_Stack
8554 if SS_Last >= Scope_Stack.First
8555 and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard
8558 End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause);
8561 -- If the call is from within a compilation unit, as when called from
8562 -- Rtsfind, make current entries in scope stack invisible while we
8563 -- analyze the new unit.
8565 for J in reverse 0 .. SS_Last loop
8566 exit when Scope_Stack.Table (J).Entity = Standard_Standard
8567 or else No (Scope_Stack.Table (J).Entity);
8569 S := Scope_Stack.Table (J).Entity;
8571 Remove_From_Visibility (S);
8573 E := First_Entity (S);
8574 while Present (E) loop
8575 Remove_From_Visibility (E);
8583 end Save_Scope_Stack;
8589 procedure Set_Use (L : List_Id) is
8591 Pack_Name : Node_Id;
8598 while Present (Decl) loop
8599 if Nkind (Decl) = N_Use_Package_Clause then
8600 Chain_Use_Clause (Decl);
8602 Pack_Name := First (Names (Decl));
8603 while Present (Pack_Name) loop
8604 Pack := Entity (Pack_Name);
8606 if Ekind (Pack) = E_Package
8607 and then Applicable_Use (Pack_Name)
8609 Use_One_Package (Pack, Decl);
8615 elsif Nkind (Decl) = N_Use_Type_Clause then
8616 Chain_Use_Clause (Decl);
8618 Id := First (Subtype_Marks (Decl));
8619 while Present (Id) loop
8620 if Entity (Id) /= Any_Type then
8633 ---------------------
8634 -- Use_One_Package --
8635 ---------------------
8637 procedure Use_One_Package (P : Entity_Id; N : Node_Id) is
8640 Current_Instance : Entity_Id := Empty;
8642 Private_With_OK : Boolean := False;
8645 if Ekind (P) /= E_Package then
8650 Set_Current_Use_Clause (P, N);
8652 -- Ada 2005 (AI-50217): Check restriction
8654 if From_Limited_With (P) then
8655 Error_Msg_N ("limited withed package cannot appear in use clause", N);
8658 -- Find enclosing instance, if any
8661 Current_Instance := Current_Scope;
8662 while not Is_Generic_Instance (Current_Instance) loop
8663 Current_Instance := Scope (Current_Instance);
8666 if No (Hidden_By_Use_Clause (N)) then
8667 Set_Hidden_By_Use_Clause (N, New_Elmt_List);
8671 -- If unit is a package renaming, indicate that the renamed
8672 -- package is also in use (the flags on both entities must
8673 -- remain consistent, and a subsequent use of either of them
8674 -- should be recognized as redundant).
8676 if Present (Renamed_Object (P)) then
8677 Set_In_Use (Renamed_Object (P));
8678 Set_Current_Use_Clause (Renamed_Object (P), N);
8679 Real_P := Renamed_Object (P);
8684 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
8685 -- found in the private part of a package specification
8687 if In_Private_Part (Current_Scope)
8688 and then Has_Private_With (P)
8689 and then Is_Child_Unit (Current_Scope)
8690 and then Is_Child_Unit (P)
8691 and then Is_Ancestor_Package (Scope (Current_Scope), P)
8693 Private_With_OK := True;
8696 -- Loop through entities in one package making them potentially
8699 Id := First_Entity (P);
8701 and then (Id /= First_Private_Entity (P)
8702 or else Private_With_OK) -- Ada 2005 (AI-262)
8704 Prev := Current_Entity (Id);
8705 while Present (Prev) loop
8706 if Is_Immediately_Visible (Prev)
8707 and then (not Is_Overloadable (Prev)
8708 or else not Is_Overloadable (Id)
8709 or else (Type_Conformant (Id, Prev)))
8711 if No (Current_Instance) then
8713 -- Potentially use-visible entity remains hidden
8715 goto Next_Usable_Entity;
8717 -- A use clause within an instance hides outer global entities,
8718 -- which are not used to resolve local entities in the
8719 -- instance. Note that the predefined entities in Standard
8720 -- could not have been hidden in the generic by a use clause,
8721 -- and therefore remain visible. Other compilation units whose
8722 -- entities appear in Standard must be hidden in an instance.
8724 -- To determine whether an entity is external to the instance
8725 -- we compare the scope depth of its scope with that of the
8726 -- current instance. However, a generic actual of a subprogram
8727 -- instance is declared in the wrapper package but will not be
8728 -- hidden by a use-visible entity. similarly, an entity that is
8729 -- declared in an enclosing instance will not be hidden by an
8730 -- an entity declared in a generic actual, which can only have
8731 -- been use-visible in the generic and will not have hidden the
8732 -- entity in the generic parent.
8734 -- If Id is called Standard, the predefined package with the
8735 -- same name is in the homonym chain. It has to be ignored
8736 -- because it has no defined scope (being the only entity in
8737 -- the system with this mandated behavior).
8739 elsif not Is_Hidden (Id)
8740 and then Present (Scope (Prev))
8741 and then not Is_Wrapper_Package (Scope (Prev))
8742 and then Scope_Depth (Scope (Prev)) <
8743 Scope_Depth (Current_Instance)
8744 and then (Scope (Prev) /= Standard_Standard
8745 or else Sloc (Prev) > Standard_Location)
8747 if In_Open_Scopes (Scope (Prev))
8748 and then Is_Generic_Instance (Scope (Prev))
8749 and then Present (Associated_Formal_Package (P))
8754 Set_Is_Potentially_Use_Visible (Id);
8755 Set_Is_Immediately_Visible (Prev, False);
8756 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8760 -- A user-defined operator is not use-visible if the predefined
8761 -- operator for the type is immediately visible, which is the case
8762 -- if the type of the operand is in an open scope. This does not
8763 -- apply to user-defined operators that have operands of different
8764 -- types, because the predefined mixed mode operations (multiply
8765 -- and divide) apply to universal types and do not hide anything.
8767 elsif Ekind (Prev) = E_Operator
8768 and then Operator_Matches_Spec (Prev, Id)
8769 and then In_Open_Scopes
8770 (Scope (Base_Type (Etype (First_Formal (Id)))))
8771 and then (No (Next_Formal (First_Formal (Id)))
8772 or else Etype (First_Formal (Id)) =
8773 Etype (Next_Formal (First_Formal (Id)))
8774 or else Chars (Prev) = Name_Op_Expon)
8776 goto Next_Usable_Entity;
8778 -- In an instance, two homonyms may become use_visible through the
8779 -- actuals of distinct formal packages. In the generic, only the
8780 -- current one would have been visible, so make the other one
8783 elsif Present (Current_Instance)
8784 and then Is_Potentially_Use_Visible (Prev)
8785 and then not Is_Overloadable (Prev)
8786 and then Scope (Id) /= Scope (Prev)
8787 and then Used_As_Generic_Actual (Scope (Prev))
8788 and then Used_As_Generic_Actual (Scope (Id))
8789 and then not In_Same_List (Current_Use_Clause (Scope (Prev)),
8790 Current_Use_Clause (Scope (Id)))
8792 Set_Is_Potentially_Use_Visible (Prev, False);
8793 Append_Elmt (Prev, Hidden_By_Use_Clause (N));
8796 Prev := Homonym (Prev);
8799 -- On exit, we know entity is not hidden, unless it is private
8801 if not Is_Hidden (Id)
8802 and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id))
8804 Set_Is_Potentially_Use_Visible (Id);
8806 if Is_Private_Type (Id) and then Present (Full_View (Id)) then
8807 Set_Is_Potentially_Use_Visible (Full_View (Id));
8811 <<Next_Usable_Entity>>
8815 -- Child units are also made use-visible by a use clause, but they may
8816 -- appear after all visible declarations in the parent entity list.
8818 while Present (Id) loop
8819 if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then
8820 Set_Is_Potentially_Use_Visible (Id);
8826 if Chars (Real_P) = Name_System
8827 and then Scope (Real_P) = Standard_Standard
8828 and then Present_System_Aux (N)
8830 Use_One_Package (System_Aux_Id, N);
8833 end Use_One_Package;
8839 procedure Use_One_Type (Id : Node_Id; Installed : Boolean := False) is
8841 Is_Known_Used : Boolean;
8845 function Spec_Reloaded_For_Body return Boolean;
8846 -- Determine whether the compilation unit is a package body and the use
8847 -- type clause is in the spec of the same package. Even though the spec
8848 -- was analyzed first, its context is reloaded when analysing the body.
8850 procedure Use_Class_Wide_Operations (Typ : Entity_Id);
8851 -- AI05-150: if the use_type_clause carries the "all" qualifier,
8852 -- class-wide operations of ancestor types are use-visible if the
8853 -- ancestor type is visible.
8855 ----------------------------
8856 -- Spec_Reloaded_For_Body --
8857 ----------------------------
8859 function Spec_Reloaded_For_Body return Boolean is
8861 if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then
8863 Spec : constant Node_Id :=
8864 Parent (List_Containing (Parent (Id)));
8867 -- Check whether type is declared in a package specification,
8868 -- and current unit is the corresponding package body. The
8869 -- use clauses themselves may be within a nested package.
8872 Nkind (Spec) = N_Package_Specification
8874 In_Same_Source_Unit (Corresponding_Body (Parent (Spec)),
8875 Cunit_Entity (Current_Sem_Unit));
8880 end Spec_Reloaded_For_Body;
8882 -------------------------------
8883 -- Use_Class_Wide_Operations --
8884 -------------------------------
8886 procedure Use_Class_Wide_Operations (Typ : Entity_Id) is
8890 function Is_Class_Wide_Operation_Of
8892 T : Entity_Id) return Boolean;
8893 -- Determine whether a subprogram has a class-wide parameter or
8894 -- result that is T'Class.
8896 ---------------------------------
8897 -- Is_Class_Wide_Operation_Of --
8898 ---------------------------------
8900 function Is_Class_Wide_Operation_Of
8902 T : Entity_Id) return Boolean
8907 Formal := First_Formal (Op);
8908 while Present (Formal) loop
8909 if Etype (Formal) = Class_Wide_Type (T) then
8912 Next_Formal (Formal);
8915 if Etype (Op) = Class_Wide_Type (T) then
8920 end Is_Class_Wide_Operation_Of;
8922 -- Start of processing for Use_Class_Wide_Operations
8925 Scop := Scope (Typ);
8926 if not Is_Hidden (Scop) then
8927 Ent := First_Entity (Scop);
8928 while Present (Ent) loop
8929 if Is_Overloadable (Ent)
8930 and then Is_Class_Wide_Operation_Of (Ent, Typ)
8931 and then not Is_Potentially_Use_Visible (Ent)
8933 Set_Is_Potentially_Use_Visible (Ent);
8934 Append_Elmt (Ent, Used_Operations (Parent (Id)));
8941 if Is_Derived_Type (Typ) then
8942 Use_Class_Wide_Operations (Etype (Base_Type (Typ)));
8944 end Use_Class_Wide_Operations;
8946 -- Start of processing for Use_One_Type
8949 -- It is the type determined by the subtype mark (8.4(8)) whose
8950 -- operations become potentially use-visible.
8952 T := Base_Type (Entity (Id));
8954 -- Either the type itself is used, the package where it is declared
8955 -- is in use or the entity is declared in the current package, thus
8960 or else In_Use (Scope (T))
8961 or else Scope (T) = Current_Scope;
8963 Set_Redundant_Use (Id,
8964 Is_Known_Used or else Is_Potentially_Use_Visible (T));
8966 if Ekind (T) = E_Incomplete_Type then
8967 Error_Msg_N ("premature usage of incomplete type", Id);
8969 elsif In_Open_Scopes (Scope (T)) then
8972 -- A limited view cannot appear in a use_type clause. However, an access
8973 -- type whose designated type is limited has the flag but is not itself
8974 -- a limited view unless we only have a limited view of its enclosing
8977 elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then
8979 ("incomplete type from limited view "
8980 & "cannot appear in use clause", Id);
8982 -- If the subtype mark designates a subtype in a different package,
8983 -- we have to check that the parent type is visible, otherwise the
8984 -- use type clause is a noop. Not clear how to do that???
8986 elsif not Redundant_Use (Id) then
8989 -- If T is tagged, primitive operators on class-wide operands
8990 -- are also available.
8992 if Is_Tagged_Type (T) then
8993 Set_In_Use (Class_Wide_Type (T));
8996 Set_Current_Use_Clause (T, Parent (Id));
8998 -- Iterate over primitive operations of the type. If an operation is
8999 -- already use_visible, it is the result of a previous use_clause,
9000 -- and already appears on the corresponding entity chain. If the
9001 -- clause is being reinstalled, operations are already use-visible.
9007 Op_List := Collect_Primitive_Operations (T);
9008 Elmt := First_Elmt (Op_List);
9009 while Present (Elmt) loop
9010 if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol
9011 or else Chars (Node (Elmt)) in Any_Operator_Name)
9012 and then not Is_Hidden (Node (Elmt))
9013 and then not Is_Potentially_Use_Visible (Node (Elmt))
9015 Set_Is_Potentially_Use_Visible (Node (Elmt));
9016 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9018 elsif Ada_Version >= Ada_2012
9019 and then All_Present (Parent (Id))
9020 and then not Is_Hidden (Node (Elmt))
9021 and then not Is_Potentially_Use_Visible (Node (Elmt))
9023 Set_Is_Potentially_Use_Visible (Node (Elmt));
9024 Append_Elmt (Node (Elmt), Used_Operations (Parent (Id)));
9031 if Ada_Version >= Ada_2012
9032 and then All_Present (Parent (Id))
9033 and then Is_Tagged_Type (T)
9035 Use_Class_Wide_Operations (T);
9039 -- If warning on redundant constructs, check for unnecessary WITH
9041 if Warn_On_Redundant_Constructs
9042 and then Is_Known_Used
9044 -- with P; with P; use P;
9045 -- package P is package X is package body X is
9046 -- type T ... use P.T;
9048 -- The compilation unit is the body of X. GNAT first compiles the
9049 -- spec of X, then proceeds to the body. At that point P is marked
9050 -- as use visible. The analysis then reinstalls the spec along with
9051 -- its context. The use clause P.T is now recognized as redundant,
9052 -- but in the wrong context. Do not emit a warning in such cases.
9053 -- Do not emit a warning either if we are in an instance, there is
9054 -- no redundancy between an outer use_clause and one that appears
9055 -- within the generic.
9057 and then not Spec_Reloaded_For_Body
9058 and then not In_Instance
9060 -- The type already has a use clause
9064 -- Case where we know the current use clause for the type
9066 if Present (Current_Use_Clause (T)) then
9067 Use_Clause_Known : declare
9068 Clause1 : constant Node_Id := Parent (Id);
9069 Clause2 : constant Node_Id := Current_Use_Clause (T);
9076 function Entity_Of_Unit (U : Node_Id) return Entity_Id;
9077 -- Return the appropriate entity for determining which unit
9078 -- has a deeper scope: the defining entity for U, unless U
9079 -- is a package instance, in which case we retrieve the
9080 -- entity of the instance spec.
9082 --------------------
9083 -- Entity_Of_Unit --
9084 --------------------
9086 function Entity_Of_Unit (U : Node_Id) return Entity_Id is
9088 if Nkind (U) = N_Package_Instantiation
9089 and then Analyzed (U)
9091 return Defining_Entity (Instance_Spec (U));
9093 return Defining_Entity (U);
9097 -- Start of processing for Use_Clause_Known
9100 -- If both current use type clause and the use type clause
9101 -- for the type are at the compilation unit level, one of
9102 -- the units must be an ancestor of the other, and the
9103 -- warning belongs on the descendant.
9105 if Nkind (Parent (Clause1)) = N_Compilation_Unit
9107 Nkind (Parent (Clause2)) = N_Compilation_Unit
9109 -- If the unit is a subprogram body that acts as spec,
9110 -- the context clause is shared with the constructed
9111 -- subprogram spec. Clearly there is no redundancy.
9113 if Clause1 = Clause2 then
9117 Unit1 := Unit (Parent (Clause1));
9118 Unit2 := Unit (Parent (Clause2));
9120 -- If both clauses are on same unit, or one is the body
9121 -- of the other, or one of them is in a subunit, report
9122 -- redundancy on the later one.
9124 if Unit1 = Unit2 then
9125 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9126 Error_Msg_NE -- CODEFIX
9127 ("& is already use-visible through previous "
9128 & "use_type_clause #??", Clause1, T);
9131 elsif Nkind (Unit1) = N_Subunit then
9132 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9133 Error_Msg_NE -- CODEFIX
9134 ("& is already use-visible through previous "
9135 & "use_type_clause #??", Clause1, T);
9138 elsif Nkind_In (Unit2, N_Package_Body, N_Subprogram_Body)
9139 and then Nkind (Unit1) /= Nkind (Unit2)
9140 and then Nkind (Unit1) /= N_Subunit
9142 Error_Msg_Sloc := Sloc (Clause1);
9143 Error_Msg_NE -- CODEFIX
9144 ("& is already use-visible through previous "
9145 & "use_type_clause #??", Current_Use_Clause (T), T);
9149 -- There is a redundant use type clause in a child unit.
9150 -- Determine which of the units is more deeply nested.
9151 -- If a unit is a package instance, retrieve the entity
9152 -- and its scope from the instance spec.
9154 Ent1 := Entity_Of_Unit (Unit1);
9155 Ent2 := Entity_Of_Unit (Unit2);
9157 if Scope (Ent2) = Standard_Standard then
9158 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9161 elsif Scope (Ent1) = Standard_Standard then
9162 Error_Msg_Sloc := Sloc (Id);
9165 -- If both units are child units, we determine which one
9166 -- is the descendant by the scope distance to the
9167 -- ultimate parent unit.
9177 and then Present (S2)
9178 and then S1 /= Standard_Standard
9179 and then S2 /= Standard_Standard
9185 if S1 = Standard_Standard then
9186 Error_Msg_Sloc := Sloc (Id);
9189 Error_Msg_Sloc := Sloc (Current_Use_Clause (T));
9195 Error_Msg_NE -- CODEFIX
9196 ("& is already use-visible through previous "
9197 & "use_type_clause #??", Err_No, Id);
9199 -- Case where current use type clause and the use type
9200 -- clause for the type are not both at the compilation unit
9201 -- level. In this case we don't have location information.
9204 Error_Msg_NE -- CODEFIX
9205 ("& is already use-visible through previous "
9206 & "use type clause??", Id, T);
9208 end Use_Clause_Known;
9210 -- Here if Current_Use_Clause is not set for T, another case
9211 -- where we do not have the location information available.
9214 Error_Msg_NE -- CODEFIX
9215 ("& is already use-visible through previous "
9216 & "use type clause??", Id, T);
9219 -- The package where T is declared is already used
9221 elsif In_Use (Scope (T)) then
9222 Error_Msg_Sloc := Sloc (Current_Use_Clause (Scope (T)));
9223 Error_Msg_NE -- CODEFIX
9224 ("& is already use-visible through package use clause #??",
9227 -- The current scope is the package where T is declared
9230 Error_Msg_Node_2 := Scope (T);
9231 Error_Msg_NE -- CODEFIX
9232 ("& is already use-visible inside package &??", Id, T);
9241 procedure Write_Info is
9242 Id : Entity_Id := First_Entity (Current_Scope);
9245 -- No point in dumping standard entities
9247 if Current_Scope = Standard_Standard then
9251 Write_Str ("========================================================");
9253 Write_Str (" Defined Entities in ");
9254 Write_Name (Chars (Current_Scope));
9256 Write_Str ("========================================================");
9260 Write_Str ("-- none --");
9264 while Present (Id) loop
9265 Write_Entity_Info (Id, " ");
9270 if Scope (Current_Scope) = Standard_Standard then
9272 -- Print information on the current unit itself
9274 Write_Entity_Info (Current_Scope, " ");
9287 for J in reverse 1 .. Scope_Stack.Last loop
9288 S := Scope_Stack.Table (J).Entity;
9289 Write_Int (Int (S));
9290 Write_Str (" === ");
9291 Write_Name (Chars (S));
9300 procedure we (S : Entity_Id) is
9303 E := First_Entity (S);
9304 while Present (E) loop
9305 Write_Int (Int (E));
9306 Write_Str (" === ");
9307 Write_Name (Chars (E));