1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Debug
; use Debug
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Errout
; use Errout
;
31 with Exp_Tss
; use Exp_Tss
;
32 with Exp_Util
; use Exp_Util
;
33 with Fname
; use Fname
;
34 with Freeze
; use Freeze
;
35 with Impunit
; use Impunit
;
37 with Lib
.Load
; use Lib
.Load
;
38 with Lib
.Xref
; use Lib
.Xref
;
39 with Namet
; use Namet
;
40 with Namet
.Sp
; use Namet
.Sp
;
41 with Nlists
; use Nlists
;
42 with Nmake
; use Nmake
;
44 with Output
; use Output
;
45 with Restrict
; use Restrict
;
46 with Rident
; use Rident
;
47 with Rtsfind
; use Rtsfind
;
49 with Sem_Cat
; use Sem_Cat
;
50 with Sem_Ch3
; use Sem_Ch3
;
51 with Sem_Ch4
; use Sem_Ch4
;
52 with Sem_Ch6
; use Sem_Ch6
;
53 with Sem_Ch12
; use Sem_Ch12
;
54 with Sem_Disp
; use Sem_Disp
;
55 with Sem_Dist
; use Sem_Dist
;
56 with Sem_Res
; use Sem_Res
;
57 with Sem_Util
; use Sem_Util
;
58 with Sem_Type
; use Sem_Type
;
59 with Stand
; use Stand
;
60 with Sinfo
; use Sinfo
;
61 with Sinfo
.CN
; use Sinfo
.CN
;
62 with Snames
; use Snames
;
63 with Style
; use Style
;
65 with Tbuild
; use Tbuild
;
66 with Uintp
; use Uintp
;
68 package body Sem_Ch8
is
70 ------------------------------------
71 -- Visibility and Name Resolution --
72 ------------------------------------
74 -- This package handles name resolution and the collection of
75 -- interpretations for overloaded names, prior to overload resolution.
77 -- Name resolution is the process that establishes a mapping between source
78 -- identifiers and the entities they denote at each point in the program.
79 -- Each entity is represented by a defining occurrence. Each identifier
80 -- that denotes an entity points to the corresponding defining occurrence.
81 -- This is the entity of the applied occurrence. Each occurrence holds
82 -- an index into the names table, where source identifiers are stored.
84 -- Each entry in the names table for an identifier or designator uses the
85 -- Info pointer to hold a link to the currently visible entity that has
86 -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id
87 -- in package Sem_Util). The visibility is initialized at the beginning of
88 -- semantic processing to make entities in package Standard immediately
89 -- visible. The visibility table is used in a more subtle way when
90 -- compiling subunits (see below).
92 -- Entities that have the same name (i.e. homonyms) are chained. In the
93 -- case of overloaded entities, this chain holds all the possible meanings
94 -- of a given identifier. The process of overload resolution uses type
95 -- information to select from this chain the unique meaning of a given
98 -- Entities are also chained in their scope, through the Next_Entity link.
99 -- As a consequence, the name space is organized as a sparse matrix, where
100 -- each row corresponds to a scope, and each column to a source identifier.
101 -- Open scopes, that is to say scopes currently being compiled, have their
102 -- corresponding rows of entities in order, innermost scope first.
104 -- The scopes of packages that are mentioned in context clauses appear in
105 -- no particular order, interspersed among open scopes. This is because
106 -- in the course of analyzing the context of a compilation, a package
107 -- declaration is first an open scope, and subsequently an element of the
108 -- context. If subunits or child units are present, a parent unit may
109 -- appear under various guises at various times in the compilation.
111 -- When the compilation of the innermost scope is complete, the entities
112 -- defined therein are no longer visible. If the scope is not a package
113 -- declaration, these entities are never visible subsequently, and can be
114 -- removed from visibility chains. If the scope is a package declaration,
115 -- its visible declarations may still be accessible. Therefore the entities
116 -- defined in such a scope are left on the visibility chains, and only
117 -- their visibility (immediately visibility or potential use-visibility)
120 -- The ordering of homonyms on their chain does not necessarily follow
121 -- the order of their corresponding scopes on the scope stack. For
122 -- example, if package P and the enclosing scope both contain entities
123 -- named E, then when compiling the package body the chain for E will
124 -- hold the global entity first, and the local one (corresponding to
125 -- the current inner scope) next. As a result, name resolution routines
126 -- do not assume any relative ordering of the homonym chains, either
127 -- for scope nesting or to order of appearance of context clauses.
129 -- When compiling a child unit, entities in the parent scope are always
130 -- immediately visible. When compiling the body of a child unit, private
131 -- entities in the parent must also be made immediately visible. There
132 -- are separate routines to make the visible and private declarations
133 -- visible at various times (see package Sem_Ch7).
135 -- +--------+ +-----+
136 -- | In use |-------->| EU1 |-------------------------->
137 -- +--------+ +-----+
139 -- +--------+ +-----+ +-----+
140 -- | Stand. |---------------->| ES1 |--------------->| ES2 |--->
141 -- +--------+ +-----+ +-----+
143 -- +---------+ | +-----+
144 -- | with'ed |------------------------------>| EW2 |--->
145 -- +---------+ | +-----+
147 -- +--------+ +-----+ +-----+
148 -- | Scope2 |---------------->| E12 |--------------->| E22 |--->
149 -- +--------+ +-----+ +-----+
151 -- +--------+ +-----+ +-----+
152 -- | Scope1 |---------------->| E11 |--------------->| E12 |--->
153 -- +--------+ +-----+ +-----+
157 -- | | with'ed |----------------------------------------->
161 -- (innermost first) | |
162 -- +----------------------------+
163 -- Names table => | Id1 | | | | Id2 |
164 -- +----------------------------+
166 -- Name resolution must deal with several syntactic forms: simple names,
167 -- qualified names, indexed names, and various forms of calls.
169 -- Each identifier points to an entry in the names table. The resolution
170 -- of a simple name consists in traversing the homonym chain, starting
171 -- from the names table. If an entry is immediately visible, it is the one
172 -- designated by the identifier. If only potentially use-visible entities
173 -- are on the chain, we must verify that they do not hide each other. If
174 -- the entity we find is overloadable, we collect all other overloadable
175 -- entities on the chain as long as they are not hidden.
177 -- To resolve expanded names, we must find the entity at the intersection
178 -- of the entity chain for the scope (the prefix) and the homonym chain
179 -- for the selector. In general, homonym chains will be much shorter than
180 -- entity chains, so it is preferable to start from the names table as
181 -- well. If the entity found is overloadable, we must collect all other
182 -- interpretations that are defined in the scope denoted by the prefix.
184 -- For records, protected types, and tasks, their local entities are
185 -- removed from visibility chains on exit from the corresponding scope.
186 -- From the outside, these entities are always accessed by selected
187 -- notation, and the entity chain for the record type, protected type,
188 -- etc. is traversed sequentially in order to find the designated entity.
190 -- The discriminants of a type and the operations of a protected type or
191 -- task are unchained on exit from the first view of the type, (such as
192 -- a private or incomplete type declaration, or a protected type speci-
193 -- fication) and re-chained when compiling the second view.
195 -- In the case of operators, we do not make operators on derived types
196 -- explicit. As a result, the notation P."+" may denote either a user-
197 -- defined function with name "+", or else an implicit declaration of the
198 -- operator "+" in package P. The resolution of expanded names always
199 -- tries to resolve an operator name as such an implicitly defined entity,
200 -- in addition to looking for explicit declarations.
202 -- All forms of names that denote entities (simple names, expanded names,
203 -- character literals in some cases) have a Entity attribute, which
204 -- identifies the entity denoted by the name.
206 ---------------------
207 -- The Scope Stack --
208 ---------------------
210 -- The Scope stack keeps track of the scopes currently been compiled.
211 -- Every entity that contains declarations (including records) is placed
212 -- on the scope stack while it is being processed, and removed at the end.
213 -- Whenever a non-package scope is exited, the entities defined therein
214 -- are removed from the visibility table, so that entities in outer scopes
215 -- become visible (see previous description). On entry to Sem, the scope
216 -- stack only contains the package Standard. As usual, subunits complicate
217 -- this picture ever so slightly.
219 -- The Rtsfind mechanism can force a call to Semantics while another
220 -- compilation is in progress. The unit retrieved by Rtsfind must be
221 -- compiled in its own context, and has no access to the visibility of
222 -- the unit currently being compiled. The procedures Save_Scope_Stack and
223 -- Restore_Scope_Stack make entities in current open scopes invisible
224 -- before compiling the retrieved unit, and restore the compilation
225 -- environment afterwards.
227 ------------------------
228 -- Compiling subunits --
229 ------------------------
231 -- Subunits must be compiled in the environment of the corresponding stub,
232 -- that is to say with the same visibility into the parent (and its
233 -- context) that is available at the point of the stub declaration, but
234 -- with the additional visibility provided by the context clause of the
235 -- subunit itself. As a result, compilation of a subunit forces compilation
236 -- of the parent (see description in lib-). At the point of the stub
237 -- declaration, Analyze is called recursively to compile the proper body of
238 -- the subunit, but without reinitializing the names table, nor the scope
239 -- stack (i.e. standard is not pushed on the stack). In this fashion the
240 -- context of the subunit is added to the context of the parent, and the
241 -- subunit is compiled in the correct environment. Note that in the course
242 -- of processing the context of a subunit, Standard will appear twice on
243 -- the scope stack: once for the parent of the subunit, and once for the
244 -- unit in the context clause being compiled. However, the two sets of
245 -- entities are not linked by homonym chains, so that the compilation of
246 -- any context unit happens in a fresh visibility environment.
248 -------------------------------
249 -- Processing of USE Clauses --
250 -------------------------------
252 -- Every defining occurrence has a flag indicating if it is potentially use
253 -- visible. Resolution of simple names examines this flag. The processing
254 -- of use clauses consists in setting this flag on all visible entities
255 -- defined in the corresponding package. On exit from the scope of the use
256 -- clause, the corresponding flag must be reset. However, a package may
257 -- appear in several nested use clauses (pathological but legal, alas!)
258 -- which forces us to use a slightly more involved scheme:
260 -- a) The defining occurrence for a package holds a flag -In_Use- to
261 -- indicate that it is currently in the scope of a use clause. If a
262 -- redundant use clause is encountered, then the corresponding occurrence
263 -- of the package name is flagged -Redundant_Use-.
265 -- b) On exit from a scope, the use clauses in its declarative part are
266 -- scanned. The visibility flag is reset in all entities declared in
267 -- package named in a use clause, as long as the package is not flagged
268 -- as being in a redundant use clause (in which case the outer use
269 -- clause is still in effect, and the direct visibility of its entities
270 -- must be retained).
272 -- Note that entities are not removed from their homonym chains on exit
273 -- from the package specification. A subsequent use clause does not need
274 -- to rechain the visible entities, but only to establish their direct
277 -----------------------------------
278 -- Handling private declarations --
279 -----------------------------------
281 -- The principle that each entity has a single defining occurrence clashes
282 -- with the presence of two separate definitions for private types: the
283 -- first is the private type declaration, and second is the full type
284 -- declaration. It is important that all references to the type point to
285 -- the same defining occurrence, namely the first one. To enforce the two
286 -- separate views of the entity, the corresponding information is swapped
287 -- between the two declarations. Outside of the package, the defining
288 -- occurrence only contains the private declaration information, while in
289 -- the private part and the body of the package the defining occurrence
290 -- contains the full declaration. To simplify the swap, the defining
291 -- occurrence that currently holds the private declaration points to the
292 -- full declaration. During semantic processing the defining occurrence
293 -- also points to a list of private dependents, that is to say access types
294 -- or composite types whose designated types or component types are
295 -- subtypes or derived types of the private type in question. After the
296 -- full declaration has been seen, the private dependents are updated to
297 -- indicate that they have full definitions.
299 ------------------------------------
300 -- Handling of Undefined Messages --
301 ------------------------------------
303 -- In normal mode, only the first use of an undefined identifier generates
304 -- a message. The table Urefs is used to record error messages that have
305 -- been issued so that second and subsequent ones do not generate further
306 -- messages. However, the second reference causes text to be added to the
307 -- original undefined message noting "(more references follow)". The
308 -- full error list option (-gnatf) forces messages to be generated for
309 -- every reference and disconnects the use of this table.
311 type Uref_Entry
is record
313 -- Node for identifier for which original message was posted. The
314 -- Chars field of this identifier is used to detect later references
315 -- to the same identifier.
318 -- Records error message Id of original undefined message. Reset to
319 -- No_Error_Msg after the second occurrence, where it is used to add
320 -- text to the original message as described above.
323 -- Set if the message is not visible rather than undefined
326 -- Records location of error message. Used to make sure that we do
327 -- not consider a, b : undefined as two separate instances, which
328 -- would otherwise happen, since the parser converts this sequence
329 -- to a : undefined; b : undefined.
333 package Urefs
is new Table
.Table
(
334 Table_Component_Type
=> Uref_Entry
,
335 Table_Index_Type
=> Nat
,
336 Table_Low_Bound
=> 1,
338 Table_Increment
=> 100,
339 Table_Name
=> "Urefs");
341 Candidate_Renaming
: Entity_Id
;
342 -- Holds a candidate interpretation that appears in a subprogram renaming
343 -- declaration and does not match the given specification, but matches at
344 -- least on the first formal. Allows better error message when given
345 -- specification omits defaulted parameters, a common error.
347 -----------------------
348 -- Local Subprograms --
349 -----------------------
351 procedure Analyze_Generic_Renaming
354 -- Common processing for all three kinds of generic renaming declarations.
355 -- Enter new name and indicate that it renames the generic unit.
357 procedure Analyze_Renamed_Character
361 -- Renamed entity is given by a character literal, which must belong
362 -- to the return type of the new entity. Is_Body indicates whether the
363 -- declaration is a renaming_as_body. If the original declaration has
364 -- already been frozen (because of an intervening body, e.g.) the body of
365 -- the function must be built now. The same applies to the following
366 -- various renaming procedures.
368 procedure Analyze_Renamed_Dereference
372 -- Renamed entity is given by an explicit dereference. Prefix must be a
373 -- conformant access_to_subprogram type.
375 procedure Analyze_Renamed_Entry
379 -- If the renamed entity in a subprogram renaming is an entry or protected
380 -- subprogram, build a body for the new entity whose only statement is a
381 -- call to the renamed entity.
383 procedure Analyze_Renamed_Family_Member
387 -- Used when the renamed entity is an indexed component. The prefix must
388 -- denote an entry family.
390 procedure Analyze_Renamed_Primitive_Operation
394 -- If the renamed entity in a subprogram renaming is a primitive operation
395 -- or a class-wide operation in prefix form, save the target object, which
396 -- must be added to the list of actuals in any subsequent call.
398 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean;
399 -- Common code to Use_One_Package and Set_Use, to determine whether
400 -- use clause must be processed. Pack_Name is an entity name that
401 -- references the package in question.
403 procedure Attribute_Renaming
(N
: Node_Id
);
404 -- Analyze renaming of attribute as function. The renaming declaration N
405 -- is rewritten as a function body that returns the attribute reference
406 -- applied to the formals of the function.
408 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
);
409 -- A renaming_as_body may occur after the entity of the original decla-
410 -- ration has been frozen. In that case, the body of the new entity must
411 -- be built now, because the usual mechanism of building the renamed
412 -- body at the point of freezing will not work. Subp is the subprogram
413 -- for which N provides the Renaming_As_Body.
415 procedure Check_In_Previous_With_Clause
418 -- N is a use_package clause and Nam the package name, or N is a use_type
419 -- clause and Nam is the prefix of the type name. In either case, verify
420 -- that the package is visible at that point in the context: either it
421 -- appears in a previous with_clause, or because it is a fully qualified
422 -- name and the root ancestor appears in a previous with_clause.
424 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
);
425 -- Verify that the entity in a renaming declaration that is a library unit
426 -- is itself a library unit and not a nested unit or subunit. Also check
427 -- that if the renaming is a child unit of a generic parent, then the
428 -- renamed unit must also be a child unit of that parent. Finally, verify
429 -- that a renamed generic unit is not an implicit child declared within
430 -- an instance of the parent.
432 procedure Chain_Use_Clause
(N
: Node_Id
);
433 -- Chain use clause onto list of uses clauses headed by First_Use_Clause in
434 -- the proper scope table entry. This is usually the current scope, but it
435 -- will be an inner scope when installing the use clauses of the private
436 -- declarations of a parent unit prior to compiling the private part of a
437 -- child unit. This chain is traversed when installing/removing use clauses
438 -- when compiling a subunit or instantiating a generic body on the fly,
439 -- when it is necessary to save and restore full environments.
441 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean;
442 -- Find a type derived from Character or Wide_Character in the prefix of N.
443 -- Used to resolved qualified names whose selector is a character literal.
445 function Has_Private_With
(E
: Entity_Id
) return Boolean;
446 -- Ada 2005 (AI-262): Determines if the current compilation unit has a
447 -- private with on E.
449 procedure Find_Expanded_Name
(N
: Node_Id
);
450 -- Selected component is known to be expanded name. Verify legality
451 -- of selector given the scope denoted by prefix.
453 function Find_Renamed_Entity
457 Is_Actual
: Boolean := False) return Entity_Id
;
458 -- Find the renamed entity that corresponds to the given parameter profile
459 -- in a subprogram renaming declaration. The renamed entity may be an
460 -- operator, a subprogram, an entry, or a protected operation. Is_Actual
461 -- indicates that the renaming is the one generated for an actual subpro-
462 -- gram in an instance, for which special visibility checks apply.
464 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean;
465 -- N is an expanded name whose selector is an operator name (e.g. P."+").
466 -- declarative part contains an implicit declaration of an operator if it
467 -- has a declaration of a type to which one of the predefined operators
468 -- apply. The existence of this routine is an implementation artifact. A
469 -- more straightforward but more space-consuming choice would be to make
470 -- all inherited operators explicit in the symbol table.
472 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
);
473 -- A subprogram defined by a renaming declaration inherits the parameter
474 -- profile of the renamed entity. The subtypes given in the subprogram
475 -- specification are discarded and replaced with those of the renamed
476 -- subprogram, which are then used to recheck the default values.
478 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean;
479 -- Prefix is appropriate for record if it is of a record type, or an access
482 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean;
483 -- True if it is of a task type, a protected type, or else an access to one
486 procedure Note_Redundant_Use
(Clause
: Node_Id
);
487 -- Mark the name in a use clause as redundant if the corresponding entity
488 -- is already use-visible. Emit a warning if the use clause comes from
489 -- source and the proper warnings are enabled.
491 procedure Premature_Usage
(N
: Node_Id
);
492 -- Diagnose usage of an entity before it is visible
494 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
);
495 -- Make visible entities declared in package P potentially use-visible
496 -- in the current context. Also used in the analysis of subunits, when
497 -- re-installing use clauses of parent units. N is the use_clause that
498 -- names P (and possibly other packages).
500 procedure Use_One_Type
(Id
: Node_Id
);
501 -- Id is the subtype mark from a use type clause. This procedure makes
502 -- the primitive operators of the type potentially use-visible.
504 procedure Write_Info
;
505 -- Write debugging information on entities declared in current scope
507 procedure Write_Scopes
;
508 pragma Warnings
(Off
, Write_Scopes
);
509 -- Debugging information: dump all entities on scope stack
511 --------------------------------
512 -- Analyze_Exception_Renaming --
513 --------------------------------
515 -- The language only allows a single identifier, but the tree holds an
516 -- identifier list. The parser has already issued an error message if
517 -- there is more than one element in the list.
519 procedure Analyze_Exception_Renaming
(N
: Node_Id
) is
520 Id
: constant Node_Id
:= Defining_Identifier
(N
);
521 Nam
: constant Node_Id
:= Name
(N
);
527 Set_Ekind
(Id
, E_Exception
);
528 Set_Exception_Code
(Id
, Uint_0
);
529 Set_Etype
(Id
, Standard_Exception_Type
);
530 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
532 if not Is_Entity_Name
(Nam
) or else
533 Ekind
(Entity
(Nam
)) /= E_Exception
535 Error_Msg_N
("invalid exception name in renaming", Nam
);
537 if Present
(Renamed_Object
(Entity
(Nam
))) then
538 Set_Renamed_Object
(Id
, Renamed_Object
(Entity
(Nam
)));
540 Set_Renamed_Object
(Id
, Entity
(Nam
));
543 end Analyze_Exception_Renaming
;
545 ---------------------------
546 -- Analyze_Expanded_Name --
547 ---------------------------
549 procedure Analyze_Expanded_Name
(N
: Node_Id
) is
551 -- If the entity pointer is already set, this is an internal node, or a
552 -- node that is analyzed more than once, after a tree modification. In
553 -- such a case there is no resolution to perform, just set the type. For
554 -- completeness, analyze prefix as well.
556 if Present
(Entity
(N
)) then
557 if Is_Type
(Entity
(N
)) then
558 Set_Etype
(N
, Entity
(N
));
560 Set_Etype
(N
, Etype
(Entity
(N
)));
563 Analyze
(Prefix
(N
));
566 Find_Expanded_Name
(N
);
568 end Analyze_Expanded_Name
;
570 ---------------------------------------
571 -- Analyze_Generic_Function_Renaming --
572 ---------------------------------------
574 procedure Analyze_Generic_Function_Renaming
(N
: Node_Id
) is
576 Analyze_Generic_Renaming
(N
, E_Generic_Function
);
577 end Analyze_Generic_Function_Renaming
;
579 --------------------------------------
580 -- Analyze_Generic_Package_Renaming --
581 --------------------------------------
583 procedure Analyze_Generic_Package_Renaming
(N
: Node_Id
) is
585 -- Apply the Text_IO Kludge here, since we may be renaming one of the
586 -- subpackages of Text_IO, then join common routine.
588 Text_IO_Kludge
(Name
(N
));
590 Analyze_Generic_Renaming
(N
, E_Generic_Package
);
591 end Analyze_Generic_Package_Renaming
;
593 ----------------------------------------
594 -- Analyze_Generic_Procedure_Renaming --
595 ----------------------------------------
597 procedure Analyze_Generic_Procedure_Renaming
(N
: Node_Id
) is
599 Analyze_Generic_Renaming
(N
, E_Generic_Procedure
);
600 end Analyze_Generic_Procedure_Renaming
;
602 ------------------------------
603 -- Analyze_Generic_Renaming --
604 ------------------------------
606 procedure Analyze_Generic_Renaming
610 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
612 Inst
: Boolean := False; -- prevent junk warning
615 if Name
(N
) = Error
then
619 Generate_Definition
(New_P
);
621 if Current_Scope
/= Standard_Standard
then
622 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
625 if Nkind
(Name
(N
)) = N_Selected_Component
then
626 Check_Generic_Child_Unit
(Name
(N
), Inst
);
631 if not Is_Entity_Name
(Name
(N
)) then
632 Error_Msg_N
("expect entity name in renaming declaration", Name
(N
));
635 Old_P
:= Entity
(Name
(N
));
639 Set_Ekind
(New_P
, K
);
641 if Etype
(Old_P
) = Any_Type
then
644 elsif Ekind
(Old_P
) /= K
then
645 Error_Msg_N
("invalid generic unit name", Name
(N
));
648 if Present
(Renamed_Object
(Old_P
)) then
649 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
651 Set_Renamed_Object
(New_P
, Old_P
);
654 Set_Is_Pure
(New_P
, Is_Pure
(Old_P
));
655 Set_Is_Preelaborated
(New_P
, Is_Preelaborated
(Old_P
));
657 Set_Etype
(New_P
, Etype
(Old_P
));
658 Set_Has_Completion
(New_P
);
660 if In_Open_Scopes
(Old_P
) then
661 Error_Msg_N
("within its scope, generic denotes its instance", N
);
664 Check_Library_Unit_Renaming
(N
, Old_P
);
666 end Analyze_Generic_Renaming
;
668 -----------------------------
669 -- Analyze_Object_Renaming --
670 -----------------------------
672 procedure Analyze_Object_Renaming
(N
: Node_Id
) is
673 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
675 Nam
: constant Node_Id
:= Name
(N
);
679 function In_Generic_Scope
(E
: Entity_Id
) return Boolean;
680 -- Determine whether entity E is inside a generic cope
682 ----------------------
683 -- In_Generic_Scope --
684 ----------------------
686 function In_Generic_Scope
(E
: Entity_Id
) return Boolean is
691 while Present
(S
) and then S
/= Standard_Standard
loop
692 if Is_Generic_Unit
(S
) then
700 end In_Generic_Scope
;
702 -- Start of processing for Analyze_Object_Renaming
709 Set_Is_Pure
(Id
, Is_Pure
(Current_Scope
));
712 -- The renaming of a component that depends on a discriminant requires
713 -- an actual subtype, because in subsequent use of the object Gigi will
714 -- be unable to locate the actual bounds. This explicit step is required
715 -- when the renaming is generated in removing side effects of an
716 -- already-analyzed expression.
718 if Nkind
(Nam
) = N_Selected_Component
719 and then Analyzed
(Nam
)
722 Dec
:= Build_Actual_Subtype_Of_Component
(Etype
(Nam
), Nam
);
724 if Present
(Dec
) then
725 Insert_Action
(N
, Dec
);
726 T
:= Defining_Identifier
(Dec
);
730 -- Complete analysis of the subtype mark in any case, for ASIS use
732 if Present
(Subtype_Mark
(N
)) then
733 Find_Type
(Subtype_Mark
(N
));
736 elsif Present
(Subtype_Mark
(N
)) then
737 Find_Type
(Subtype_Mark
(N
));
738 T
:= Entity
(Subtype_Mark
(N
));
741 if Nkind
(Nam
) = N_Type_Conversion
742 and then not Is_Tagged_Type
(T
)
745 ("renaming of conversion only allowed for tagged types", Nam
);
750 -- Check that a class-wide object is not being renamed as an object
751 -- of a specific type. The test for access types is needed to exclude
752 -- cases where the renamed object is a dynamically tagged access
753 -- result, such as occurs in certain expansions.
755 if (Is_Class_Wide_Type
(Etype
(Nam
))
756 or else (Is_Dynamically_Tagged
(Nam
)
757 and then not Is_Access_Type
(T
)))
758 and then not Is_Class_Wide_Type
(T
)
760 Error_Msg_N
("dynamically tagged expression not allowed!", Nam
);
763 -- Ada 2005 (AI-230/AI-254): Access renaming
765 else pragma Assert
(Present
(Access_Definition
(N
)));
766 T
:= Access_Definition
768 N
=> Access_Definition
(N
));
770 Analyze_And_Resolve
(Nam
, T
);
772 -- Ada 2005 (AI-231): "In the case where the type is defined by an
773 -- access_definition, the renamed entity shall be of an access-to-
774 -- constant type if and only if the access_definition defines an
775 -- access-to-constant type" ARM 8.5.1(4)
777 if Constant_Present
(Access_Definition
(N
))
778 and then not Is_Access_Constant
(Etype
(Nam
))
780 Error_Msg_N
("(Ada 2005): the renamed object is not "
781 & "access-to-constant (RM 8.5.1(6))", N
);
785 -- Special processing for renaming function return object
787 if Nkind
(Nam
) = N_Function_Call
788 and then Comes_From_Source
(Nam
)
792 -- Usage is illegal in Ada 83
796 ("(Ada 83) cannot rename function return object", Nam
);
798 -- In Ada 95, warn for odd case of renaming parameterless function
799 -- call if this is not a limited type (where this is useful)
802 if Warn_On_Object_Renames_Function
803 and then No
(Parameter_Associations
(Nam
))
804 and then not Is_Limited_Type
(Etype
(Nam
))
807 ("?renaming function result object is suspicious",
810 ("\?function & will be called only once",
811 Nam
, Entity
(Name
(Nam
)));
813 ("\?suggest using an initialized constant object instead",
819 -- An object renaming requires an exact match of the type. Class-wide
820 -- matching is not allowed.
822 if Is_Class_Wide_Type
(T
)
823 and then Base_Type
(Etype
(Nam
)) /= Base_Type
(T
)
830 -- (Ada 2005: AI-326): Handle wrong use of incomplete type
832 if Nkind
(Nam
) = N_Explicit_Dereference
833 and then Ekind
(Etype
(T2
)) = E_Incomplete_Type
835 Error_Msg_NE
("invalid use of incomplete type&", Id
, T2
);
837 elsif Ekind
(Etype
(T
)) = E_Incomplete_Type
then
838 Error_Msg_NE
("invalid use of incomplete type&", Id
, T
);
844 if Ada_Version
>= Ada_05
845 and then Nkind
(Nam
) = N_Attribute_Reference
846 and then Attribute_Name
(Nam
) = Name_Priority
850 elsif Ada_Version
>= Ada_05
851 and then Nkind
(Nam
) in N_Has_Entity
858 if Nkind
(Nam
) = N_Attribute_Reference
then
859 Nam_Ent
:= Entity
(Prefix
(Nam
));
861 Nam_Ent
:= Entity
(Nam
);
864 Nam_Decl
:= Parent
(Nam_Ent
);
866 if Has_Null_Exclusion
(N
)
867 and then not Has_Null_Exclusion
(Nam_Decl
)
869 -- Ada 2005 (AI-423): If the object name denotes a generic
870 -- formal object of a generic unit G, and the object renaming
871 -- declaration occurs within the body of G or within the body
872 -- of a generic unit declared within the declarative region
873 -- of G, then the declaration of the formal object of G must
874 -- have a null exclusion.
876 if Is_Formal_Object
(Nam_Ent
)
877 and then In_Generic_Scope
(Id
)
880 ("renamed formal does not exclude `NULL` "
881 & "(RM 8.5.1(4.6/2))", N
);
883 -- Ada 2005 (AI-423): Otherwise, the subtype of the object name
884 -- shall exclude null.
886 elsif not Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
888 ("renamed object does not exclude `NULL` "
889 & "(RM 8.5.1(4.6/2))", N
);
891 elsif Can_Never_Be_Null
(Etype
(Nam_Ent
)) then
893 ("`NOT NULL` not allowed (type of& already excludes null)",
898 elsif Has_Null_Exclusion
(N
)
899 and then No
(Access_Definition
(N
))
900 and then Can_Never_Be_Null
(T
)
903 ("`NOT NULL` not allowed (& already excludes null)", N
, T
);
908 Set_Ekind
(Id
, E_Variable
);
909 Init_Size_Align
(Id
);
911 if T
= Any_Type
or else Etype
(Nam
) = Any_Type
then
914 -- Verify that the renamed entity is an object or a function call. It
915 -- may have been rewritten in several ways.
917 elsif Is_Object_Reference
(Nam
) then
918 if Comes_From_Source
(N
)
919 and then Is_Dependent_Component_Of_Mutable_Object
(Nam
)
922 ("illegal renaming of discriminant-dependent component", Nam
);
927 -- A static function call may have been folded into a literal
929 elsif Nkind
(Original_Node
(Nam
)) = N_Function_Call
931 -- When expansion is disabled, attribute reference is not
932 -- rewritten as function call. Otherwise it may be rewritten
933 -- as a conversion, so check original node.
935 or else (Nkind
(Original_Node
(Nam
)) = N_Attribute_Reference
936 and then Is_Function_Attribute_Name
937 (Attribute_Name
(Original_Node
(Nam
))))
939 -- Weird but legal, equivalent to renaming a function call.
940 -- Illegal if the literal is the result of constant-folding an
941 -- attribute reference that is not a function.
943 or else (Is_Entity_Name
(Nam
)
944 and then Ekind
(Entity
(Nam
)) = E_Enumeration_Literal
946 Nkind
(Original_Node
(Nam
)) /= N_Attribute_Reference
)
948 or else (Nkind
(Nam
) = N_Type_Conversion
949 and then Is_Tagged_Type
(Entity
(Subtype_Mark
(Nam
))))
953 elsif Nkind
(Nam
) = N_Type_Conversion
then
955 ("renaming of conversion only allowed for tagged types", Nam
);
959 elsif Ada_Version
>= Ada_05
960 and then Nkind
(Nam
) = N_Attribute_Reference
961 and then Attribute_Name
(Nam
) = Name_Priority
965 -- Allow internally generated x'Reference expression
967 elsif Nkind
(Nam
) = N_Reference
then
971 Error_Msg_N
("expect object name in renaming", Nam
);
976 if not Is_Variable
(Nam
) then
977 Set_Ekind
(Id
, E_Constant
);
978 Set_Never_Set_In_Source
(Id
, True);
979 Set_Is_True_Constant
(Id
, True);
982 Set_Renamed_Object
(Id
, Nam
);
983 end Analyze_Object_Renaming
;
985 ------------------------------
986 -- Analyze_Package_Renaming --
987 ------------------------------
989 procedure Analyze_Package_Renaming
(N
: Node_Id
) is
990 New_P
: constant Entity_Id
:= Defining_Entity
(N
);
995 if Name
(N
) = Error
then
999 -- Apply Text_IO kludge here, since we may be renaming one of the
1000 -- children of Text_IO.
1002 Text_IO_Kludge
(Name
(N
));
1004 if Current_Scope
/= Standard_Standard
then
1005 Set_Is_Pure
(New_P
, Is_Pure
(Current_Scope
));
1011 if Is_Entity_Name
(Name
(N
)) then
1012 Old_P
:= Entity
(Name
(N
));
1017 if Etype
(Old_P
) = Any_Type
then
1019 ("expect package name in renaming", Name
(N
));
1021 elsif Ekind
(Old_P
) /= E_Package
1022 and then not (Ekind
(Old_P
) = E_Generic_Package
1023 and then In_Open_Scopes
(Old_P
))
1025 if Ekind
(Old_P
) = E_Generic_Package
then
1027 ("generic package cannot be renamed as a package", Name
(N
));
1029 Error_Msg_Sloc
:= Sloc
(Old_P
);
1031 ("expect package name in renaming, found& declared#",
1035 -- Set basic attributes to minimize cascaded errors
1037 Set_Ekind
(New_P
, E_Package
);
1038 Set_Etype
(New_P
, Standard_Void_Type
);
1040 -- Here for OK package renaming
1043 -- Entities in the old package are accessible through the renaming
1044 -- entity. The simplest implementation is to have both packages share
1047 Set_Ekind
(New_P
, E_Package
);
1048 Set_Etype
(New_P
, Standard_Void_Type
);
1050 if Present
(Renamed_Object
(Old_P
)) then
1051 Set_Renamed_Object
(New_P
, Renamed_Object
(Old_P
));
1053 Set_Renamed_Object
(New_P
, Old_P
);
1056 Set_Has_Completion
(New_P
);
1058 Set_First_Entity
(New_P
, First_Entity
(Old_P
));
1059 Set_Last_Entity
(New_P
, Last_Entity
(Old_P
));
1060 Set_First_Private_Entity
(New_P
, First_Private_Entity
(Old_P
));
1061 Check_Library_Unit_Renaming
(N
, Old_P
);
1062 Generate_Reference
(Old_P
, Name
(N
));
1064 -- If the renaming is in the visible part of a package, then we set
1065 -- Renamed_In_Spec for the renamed package, to prevent giving
1066 -- warnings about no entities referenced. Such a warning would be
1067 -- overenthusiastic, since clients can see entities in the renamed
1068 -- package via the visible package renaming.
1071 Ent
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1073 if Ekind
(Ent
) = E_Package
1074 and then not In_Private_Part
(Ent
)
1075 and then In_Extended_Main_Source_Unit
(N
)
1076 and then Ekind
(Old_P
) = E_Package
1078 Set_Renamed_In_Spec
(Old_P
);
1082 -- If this is the renaming declaration of a package instantiation
1083 -- within itself, it is the declaration that ends the list of actuals
1084 -- for the instantiation. At this point, the subtypes that rename
1085 -- the actuals are flagged as generic, to avoid spurious ambiguities
1086 -- if the actuals for two distinct formals happen to coincide. If
1087 -- the actual is a private type, the subtype has a private completion
1088 -- that is flagged in the same fashion.
1090 -- Resolution is identical to what is was in the original generic.
1091 -- On exit from the generic instance, these are turned into regular
1092 -- subtypes again, so they are compatible with types in their class.
1094 if not Is_Generic_Instance
(Old_P
) then
1097 Spec
:= Specification
(Unit_Declaration_Node
(Old_P
));
1100 if Nkind
(Spec
) = N_Package_Specification
1101 and then Present
(Generic_Parent
(Spec
))
1102 and then Old_P
= Current_Scope
1103 and then Chars
(New_P
) = Chars
(Generic_Parent
(Spec
))
1109 E
:= First_Entity
(Old_P
);
1114 and then Nkind
(Parent
(E
)) = N_Subtype_Declaration
1116 Set_Is_Generic_Actual_Type
(E
);
1118 if Is_Private_Type
(E
)
1119 and then Present
(Full_View
(E
))
1121 Set_Is_Generic_Actual_Type
(Full_View
(E
));
1130 end Analyze_Package_Renaming
;
1132 -------------------------------
1133 -- Analyze_Renamed_Character --
1134 -------------------------------
1136 procedure Analyze_Renamed_Character
1141 C
: constant Node_Id
:= Name
(N
);
1144 if Ekind
(New_S
) = E_Function
then
1145 Resolve
(C
, Etype
(New_S
));
1148 Check_Frozen_Renaming
(N
, New_S
);
1152 Error_Msg_N
("character literal can only be renamed as function", N
);
1154 end Analyze_Renamed_Character
;
1156 ---------------------------------
1157 -- Analyze_Renamed_Dereference --
1158 ---------------------------------
1160 procedure Analyze_Renamed_Dereference
1165 Nam
: constant Node_Id
:= Name
(N
);
1166 P
: constant Node_Id
:= Prefix
(Nam
);
1172 if not Is_Overloaded
(P
) then
1173 if Ekind
(Etype
(Nam
)) /= E_Subprogram_Type
1174 or else not Type_Conformant
(Etype
(Nam
), New_S
) then
1175 Error_Msg_N
("designated type does not match specification", P
);
1184 Get_First_Interp
(Nam
, Ind
, It
);
1186 while Present
(It
.Nam
) loop
1188 if Ekind
(It
.Nam
) = E_Subprogram_Type
1189 and then Type_Conformant
(It
.Nam
, New_S
) then
1191 if Typ
/= Any_Id
then
1192 Error_Msg_N
("ambiguous renaming", P
);
1199 Get_Next_Interp
(Ind
, It
);
1202 if Typ
= Any_Type
then
1203 Error_Msg_N
("designated type does not match specification", P
);
1208 Check_Frozen_Renaming
(N
, New_S
);
1212 end Analyze_Renamed_Dereference
;
1214 ---------------------------
1215 -- Analyze_Renamed_Entry --
1216 ---------------------------
1218 procedure Analyze_Renamed_Entry
1223 Nam
: constant Node_Id
:= Name
(N
);
1224 Sel
: constant Node_Id
:= Selector_Name
(Nam
);
1228 if Entity
(Sel
) = Any_Id
then
1230 -- Selector is undefined on prefix. Error emitted already
1232 Set_Has_Completion
(New_S
);
1236 -- Otherwise find renamed entity and build body of New_S as a call to it
1238 Old_S
:= Find_Renamed_Entity
(N
, Selector_Name
(Nam
), New_S
);
1240 if Old_S
= Any_Id
then
1241 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1244 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1245 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1246 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1249 -- Only mode conformance required for a renaming_as_declaration
1251 Check_Mode_Conformant
(New_S
, Old_S
, N
);
1254 Inherit_Renamed_Profile
(New_S
, Old_S
);
1256 -- The prefix can be an arbitrary expression that yields a task
1257 -- type, so it must be resolved.
1259 Resolve
(Prefix
(Nam
), Scope
(Old_S
));
1262 Set_Convention
(New_S
, Convention
(Old_S
));
1263 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1266 Check_Frozen_Renaming
(N
, New_S
);
1268 end Analyze_Renamed_Entry
;
1270 -----------------------------------
1271 -- Analyze_Renamed_Family_Member --
1272 -----------------------------------
1274 procedure Analyze_Renamed_Family_Member
1279 Nam
: constant Node_Id
:= Name
(N
);
1280 P
: constant Node_Id
:= Prefix
(Nam
);
1284 if (Is_Entity_Name
(P
) and then Ekind
(Entity
(P
)) = E_Entry_Family
)
1285 or else (Nkind
(P
) = N_Selected_Component
1287 Ekind
(Entity
(Selector_Name
(P
))) = E_Entry_Family
)
1289 if Is_Entity_Name
(P
) then
1290 Old_S
:= Entity
(P
);
1292 Old_S
:= Entity
(Selector_Name
(P
));
1295 if not Entity_Matches_Spec
(Old_S
, New_S
) then
1296 Error_Msg_N
("entry family does not match specification", N
);
1299 Check_Subtype_Conformant
(New_S
, Old_S
, N
);
1300 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1301 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1305 Error_Msg_N
("no entry family matches specification", N
);
1308 Set_Has_Completion
(New_S
, Inside_A_Generic
);
1311 Check_Frozen_Renaming
(N
, New_S
);
1313 end Analyze_Renamed_Family_Member
;
1315 -----------------------------------------
1316 -- Analyze_Renamed_Primitive_Operation --
1317 -----------------------------------------
1319 procedure Analyze_Renamed_Primitive_Operation
1328 Ctyp
: Conformance_Type
) return Boolean;
1329 -- Verify that the signatures of the renamed entity and the new entity
1330 -- match. The first formal of the renamed entity is skipped because it
1331 -- is the target object in any subsequent call.
1335 Ctyp
: Conformance_Type
) return Boolean
1341 if Ekind
(Subp
) /= Ekind
(New_S
) then
1345 Old_F
:= Next_Formal
(First_Formal
(Subp
));
1346 New_F
:= First_Formal
(New_S
);
1347 while Present
(Old_F
) and then Present
(New_F
) loop
1348 if not Conforming_Types
(Etype
(Old_F
), Etype
(New_F
), Ctyp
) then
1352 if Ctyp
>= Mode_Conformant
1353 and then Ekind
(Old_F
) /= Ekind
(New_F
)
1358 Next_Formal
(New_F
);
1359 Next_Formal
(Old_F
);
1366 if not Is_Overloaded
(Selector_Name
(Name
(N
))) then
1367 Old_S
:= Entity
(Selector_Name
(Name
(N
)));
1369 if not Conforms
(Old_S
, Type_Conformant
) then
1374 -- Find the operation that matches the given signature
1382 Get_First_Interp
(Selector_Name
(Name
(N
)), Ind
, It
);
1384 while Present
(It
.Nam
) loop
1385 if Conforms
(It
.Nam
, Type_Conformant
) then
1389 Get_Next_Interp
(Ind
, It
);
1394 if Old_S
= Any_Id
then
1395 Error_Msg_N
(" no subprogram or entry matches specification", N
);
1399 if not Conforms
(Old_S
, Subtype_Conformant
) then
1400 Error_Msg_N
("subtype conformance error in renaming", N
);
1403 Generate_Reference
(New_S
, Defining_Entity
(N
), 'b');
1404 Style
.Check_Identifier
(Defining_Entity
(N
), New_S
);
1407 -- Only mode conformance required for a renaming_as_declaration
1409 if not Conforms
(Old_S
, Mode_Conformant
) then
1410 Error_Msg_N
("mode conformance error in renaming", N
);
1414 -- Inherit_Renamed_Profile (New_S, Old_S);
1416 -- The prefix can be an arbitrary expression that yields an
1417 -- object, so it must be resolved.
1419 Resolve
(Prefix
(Name
(N
)));
1421 end Analyze_Renamed_Primitive_Operation
;
1423 ---------------------------------
1424 -- Analyze_Subprogram_Renaming --
1425 ---------------------------------
1427 procedure Analyze_Subprogram_Renaming
(N
: Node_Id
) is
1428 Formal_Spec
: constant Node_Id
:= Corresponding_Formal_Spec
(N
);
1429 Is_Actual
: constant Boolean := Present
(Formal_Spec
);
1430 Inst_Node
: Node_Id
:= Empty
;
1431 Nam
: constant Node_Id
:= Name
(N
);
1433 Old_S
: Entity_Id
:= Empty
;
1434 Rename_Spec
: Entity_Id
;
1435 Save_AV
: constant Ada_Version_Type
:= Ada_Version
;
1436 Save_AV_Exp
: constant Ada_Version_Type
:= Ada_Version_Explicit
;
1437 Spec
: constant Node_Id
:= Specification
(N
);
1439 procedure Check_Null_Exclusion
1442 -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the
1443 -- following AI rules:
1445 -- If Ren is a renaming of a formal subprogram and one of its
1446 -- parameters has a null exclusion, then the corresponding formal
1447 -- in Sub must also have one. Otherwise the subtype of the Sub's
1448 -- formal parameter must exclude null.
1450 -- If Ren is a renaming of a formal function and its return
1451 -- profile has a null exclusion, then Sub's return profile must
1452 -- have one. Otherwise the subtype of Sub's return profile must
1455 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
;
1456 -- Find renamed entity when the declaration is a renaming_as_body and
1457 -- the renamed entity may itself be a renaming_as_body. Used to enforce
1458 -- rule that a renaming_as_body is illegal if the declaration occurs
1459 -- before the subprogram it completes is frozen, and renaming indirectly
1460 -- renames the subprogram itself.(Defect Report 8652/0027).
1462 --------------------------
1463 -- Check_Null_Exclusion --
1464 --------------------------
1466 procedure Check_Null_Exclusion
1470 Ren_Formal
: Entity_Id
;
1471 Sub_Formal
: Entity_Id
;
1476 Ren_Formal
:= First_Formal
(Ren
);
1477 Sub_Formal
:= First_Formal
(Sub
);
1478 while Present
(Ren_Formal
)
1479 and then Present
(Sub_Formal
)
1481 if Has_Null_Exclusion
(Parent
(Ren_Formal
))
1483 not (Has_Null_Exclusion
(Parent
(Sub_Formal
))
1484 or else Can_Never_Be_Null
(Etype
(Sub_Formal
)))
1487 ("`NOT NULL` required for parameter &",
1488 Parent
(Sub_Formal
), Sub_Formal
);
1491 Next_Formal
(Ren_Formal
);
1492 Next_Formal
(Sub_Formal
);
1495 -- Return profile check
1497 if Nkind
(Parent
(Ren
)) = N_Function_Specification
1498 and then Nkind
(Parent
(Sub
)) = N_Function_Specification
1499 and then Has_Null_Exclusion
(Parent
(Ren
))
1501 not (Has_Null_Exclusion
(Parent
(Sub
))
1502 or else Can_Never_Be_Null
(Etype
(Sub
)))
1505 ("return must specify `NOT NULL`",
1506 Result_Definition
(Parent
(Sub
)));
1508 end Check_Null_Exclusion
;
1510 -------------------------
1511 -- Original_Subprogram --
1512 -------------------------
1514 function Original_Subprogram
(Subp
: Entity_Id
) return Entity_Id
is
1515 Orig_Decl
: Node_Id
;
1516 Orig_Subp
: Entity_Id
;
1519 -- First case: renamed entity is itself a renaming
1521 if Present
(Alias
(Subp
)) then
1522 return Alias
(Subp
);
1525 Nkind
(Unit_Declaration_Node
(Subp
)) = N_Subprogram_Declaration
1527 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)))
1529 -- Check if renamed entity is a renaming_as_body
1532 Unit_Declaration_Node
1533 (Corresponding_Body
(Unit_Declaration_Node
(Subp
)));
1535 if Nkind
(Orig_Decl
) = N_Subprogram_Renaming_Declaration
then
1536 Orig_Subp
:= Entity
(Name
(Orig_Decl
));
1538 if Orig_Subp
= Rename_Spec
then
1540 -- Circularity detected
1545 return (Original_Subprogram
(Orig_Subp
));
1553 end Original_Subprogram
;
1555 -- Start of processing for Analyze_Subprogram_Renaming
1558 -- We must test for the attribute renaming case before the Analyze
1559 -- call because otherwise Sem_Attr will complain that the attribute
1560 -- is missing an argument when it is analyzed.
1562 if Nkind
(Nam
) = N_Attribute_Reference
then
1564 -- In the case of an abstract formal subprogram association, rewrite
1565 -- an actual given by a stream attribute as the name of the
1566 -- corresponding stream primitive of the type.
1568 -- In a generic context the stream operations are not generated, and
1569 -- this must be treated as a normal attribute reference, to be
1570 -- expanded in subsequent instantiations.
1572 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
)
1573 and then Expander_Active
1576 Stream_Prim
: Entity_Id
;
1577 Prefix_Type
: constant Entity_Id
:= Entity
(Prefix
(Nam
));
1580 -- The class-wide forms of the stream attributes are not
1581 -- primitive dispatching operations (even though they
1582 -- internally dispatch to a stream attribute).
1584 if Is_Class_Wide_Type
(Prefix_Type
) then
1586 ("attribute must be a primitive dispatching operation",
1591 -- Retrieve the primitive subprogram associated with the
1592 -- attribute. This can only be a stream attribute, since those
1593 -- are the only ones that are dispatching (and the actual for
1594 -- an abstract formal subprogram must be dispatching
1598 case Attribute_Name
(Nam
) is
1601 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Input
);
1604 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Output
);
1607 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Read
);
1610 Find_Prim_Op
(Prefix_Type
, TSS_Stream_Write
);
1613 ("attribute must be a primitive"
1614 & " dispatching operation", Nam
);
1620 -- If no operation was found, and the type is limited,
1621 -- the user should have defined one.
1623 when Program_Error
=>
1624 if Is_Limited_Type
(Prefix_Type
) then
1626 ("stream operation not defined for type&",
1630 -- Otherwise, compiler should have generated default
1637 -- Rewrite the attribute into the name of its corresponding
1638 -- primitive dispatching subprogram. We can then proceed with
1639 -- the usual processing for subprogram renamings.
1642 Prim_Name
: constant Node_Id
:=
1643 Make_Identifier
(Sloc
(Nam
),
1644 Chars
=> Chars
(Stream_Prim
));
1646 Set_Entity
(Prim_Name
, Stream_Prim
);
1647 Rewrite
(Nam
, Prim_Name
);
1652 -- Normal processing for a renaming of an attribute
1655 Attribute_Renaming
(N
);
1660 -- Check whether this declaration corresponds to the instantiation
1661 -- of a formal subprogram.
1663 -- If this is an instantiation, the corresponding actual is frozen and
1664 -- error messages can be made more precise. If this is a default
1665 -- subprogram, the entity is already established in the generic, and is
1666 -- not retrieved by visibility. If it is a default with a box, the
1667 -- candidate interpretations, if any, have been collected when building
1668 -- the renaming declaration. If overloaded, the proper interpretation is
1669 -- determined in Find_Renamed_Entity. If the entity is an operator,
1670 -- Find_Renamed_Entity applies additional visibility checks.
1673 Inst_Node
:= Unit_Declaration_Node
(Formal_Spec
);
1675 if Is_Entity_Name
(Nam
)
1676 and then Present
(Entity
(Nam
))
1677 and then not Comes_From_Source
(Nam
)
1678 and then not Is_Overloaded
(Nam
)
1680 Old_S
:= Entity
(Nam
);
1681 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1685 if Ekind
(Entity
(Nam
)) = E_Operator
then
1689 if Box_Present
(Inst_Node
) then
1690 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
1692 -- If there is an immediately visible homonym of the operator
1693 -- and the declaration has a default, this is worth a warning
1694 -- because the user probably did not intend to get the pre-
1695 -- defined operator, visible in the generic declaration. To
1696 -- find if there is an intended candidate, analyze the renaming
1697 -- again in the current context.
1699 elsif Scope
(Old_S
) = Standard_Standard
1700 and then Present
(Default_Name
(Inst_Node
))
1703 Decl
: constant Node_Id
:= New_Copy_Tree
(N
);
1707 Set_Entity
(Name
(Decl
), Empty
);
1708 Analyze
(Name
(Decl
));
1710 Find_Renamed_Entity
(Decl
, Name
(Decl
), New_S
, True);
1713 and then In_Open_Scopes
(Scope
(Hidden
))
1714 and then Is_Immediately_Visible
(Hidden
)
1715 and then Comes_From_Source
(Hidden
)
1716 and then Hidden
/= Old_S
1718 Error_Msg_Sloc
:= Sloc
(Hidden
);
1719 Error_Msg_N
("?default subprogram is resolved " &
1720 "in the generic declaration " &
1721 "(RM 12.6(17))", N
);
1722 Error_Msg_NE
("\?and will not use & #", N
, Hidden
);
1730 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1734 -- Renamed entity must be analyzed first, to avoid being hidden by
1735 -- new name (which might be the same in a generic instance).
1739 -- The renaming defines a new overloaded entity, which is analyzed
1740 -- like a subprogram declaration.
1742 New_S
:= Analyze_Subprogram_Specification
(Spec
);
1745 if Current_Scope
/= Standard_Standard
then
1746 Set_Is_Pure
(New_S
, Is_Pure
(Current_Scope
));
1749 Rename_Spec
:= Find_Corresponding_Spec
(N
);
1751 -- Case of Renaming_As_Body
1753 if Present
(Rename_Spec
) then
1755 -- Renaming declaration is the completion of the declaration of
1756 -- Rename_Spec. We build an actual body for it at the freezing point.
1758 Set_Corresponding_Spec
(N
, Rename_Spec
);
1760 -- Deal with special case of stream functions of abstract types
1763 if Nkind
(Unit_Declaration_Node
(Rename_Spec
)) =
1764 N_Abstract_Subprogram_Declaration
1766 -- Input stream functions are abstract if the object type is
1767 -- abstract. Similarly, all default stream functions for an
1768 -- interface type are abstract. However, these subprograms may
1769 -- receive explicit declarations in representation clauses, making
1770 -- the attribute subprograms usable as defaults in subsequent
1772 -- In this case we rewrite the declaration to make the subprogram
1773 -- non-abstract. We remove the previous declaration, and insert
1774 -- the new one at the point of the renaming, to prevent premature
1775 -- access to unfrozen types. The new declaration reuses the
1776 -- specification of the previous one, and must not be analyzed.
1779 (Is_Primitive
(Entity
(Nam
))
1781 Is_Abstract_Type
(Find_Dispatching_Type
(Entity
(Nam
))));
1783 Old_Decl
: constant Node_Id
:=
1784 Unit_Declaration_Node
(Rename_Spec
);
1785 New_Decl
: constant Node_Id
:=
1786 Make_Subprogram_Declaration
(Sloc
(N
),
1788 Relocate_Node
(Specification
(Old_Decl
)));
1791 Insert_After
(N
, New_Decl
);
1792 Set_Is_Abstract_Subprogram
(Rename_Spec
, False);
1793 Set_Analyzed
(New_Decl
);
1797 Set_Corresponding_Body
(Unit_Declaration_Node
(Rename_Spec
), New_S
);
1799 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
1800 Error_Msg_N
("(Ada 83) renaming cannot serve as a body", N
);
1803 Set_Convention
(New_S
, Convention
(Rename_Spec
));
1804 Check_Fully_Conformant
(New_S
, Rename_Spec
);
1805 Set_Public_Status
(New_S
);
1807 -- The specification does not introduce new formals, but only
1808 -- repeats the formals of the original subprogram declaration.
1809 -- For cross-reference purposes, and for refactoring tools, we
1810 -- treat the formals of the renaming declaration as body formals.
1812 Reference_Body_Formals
(Rename_Spec
, New_S
);
1814 -- Indicate that the entity in the declaration functions like the
1815 -- corresponding body, and is not a new entity. The body will be
1816 -- constructed later at the freeze point, so indicate that the
1817 -- completion has not been seen yet.
1819 Set_Ekind
(New_S
, E_Subprogram_Body
);
1820 New_S
:= Rename_Spec
;
1821 Set_Has_Completion
(Rename_Spec
, False);
1823 -- Ada 2005: check overriding indicator
1825 if Is_Overriding_Operation
(Rename_Spec
) then
1826 if Must_Not_Override
(Specification
(N
)) then
1828 ("subprogram& overrides inherited operation",
1831 Style_Check
and then not Must_Override
(Specification
(N
))
1833 Style
.Missing_Overriding
(N
, Rename_Spec
);
1836 elsif Must_Override
(Specification
(N
)) then
1837 Error_Msg_NE
("subprogram& is not overriding", N
, Rename_Spec
);
1840 -- Normal subprogram renaming (not renaming as body)
1843 Generate_Definition
(New_S
);
1844 New_Overloaded_Entity
(New_S
);
1846 if Is_Entity_Name
(Nam
)
1847 and then Is_Intrinsic_Subprogram
(Entity
(Nam
))
1851 Check_Delayed_Subprogram
(New_S
);
1855 -- There is no need for elaboration checks on the new entity, which may
1856 -- be called before the next freezing point where the body will appear.
1857 -- Elaboration checks refer to the real entity, not the one created by
1858 -- the renaming declaration.
1860 Set_Kill_Elaboration_Checks
(New_S
, True);
1862 if Etype
(Nam
) = Any_Type
then
1863 Set_Has_Completion
(New_S
);
1866 elsif Nkind
(Nam
) = N_Selected_Component
then
1868 -- A prefix of the form A.B can designate an entry of task A, a
1869 -- protected operation of protected object A, or finally a primitive
1870 -- operation of object A. In the later case, A is an object of some
1871 -- tagged type, or an access type that denotes one such. To further
1872 -- distinguish these cases, note that the scope of a task entry or
1873 -- protected operation is type of the prefix.
1875 -- The prefix could be an overloaded function call that returns both
1876 -- kinds of operations. This overloading pathology is left to the
1877 -- dedicated reader ???
1880 T
: constant Entity_Id
:= Etype
(Prefix
(Nam
));
1889 Is_Tagged_Type
(Designated_Type
(T
))))
1890 and then Scope
(Entity
(Selector_Name
(Nam
))) /= T
1892 Analyze_Renamed_Primitive_Operation
1893 (N
, New_S
, Present
(Rename_Spec
));
1897 -- Renamed entity is an entry or protected operation. For those
1898 -- cases an explicit body is built (at the point of freezing of
1899 -- this entity) that contains a call to the renamed entity.
1901 -- This is not allowed for renaming as body if the renamed
1902 -- spec is already frozen (see RM 8.5.4(5) for details).
1904 if Present
(Rename_Spec
)
1905 and then Is_Frozen
(Rename_Spec
)
1908 ("renaming-as-body cannot rename entry as subprogram", N
);
1910 ("\since & is already frozen (RM 8.5.4(5))",
1913 Analyze_Renamed_Entry
(N
, New_S
, Present
(Rename_Spec
));
1920 elsif Nkind
(Nam
) = N_Explicit_Dereference
then
1922 -- Renamed entity is designated by access_to_subprogram expression.
1923 -- Must build body to encapsulate call, as in the entry case.
1925 Analyze_Renamed_Dereference
(N
, New_S
, Present
(Rename_Spec
));
1928 elsif Nkind
(Nam
) = N_Indexed_Component
then
1929 Analyze_Renamed_Family_Member
(N
, New_S
, Present
(Rename_Spec
));
1932 elsif Nkind
(Nam
) = N_Character_Literal
then
1933 Analyze_Renamed_Character
(N
, New_S
, Present
(Rename_Spec
));
1936 elsif (not Is_Entity_Name
(Nam
)
1937 and then Nkind
(Nam
) /= N_Operator_Symbol
)
1938 or else not Is_Overloadable
(Entity
(Nam
))
1940 Error_Msg_N
("expect valid subprogram name in renaming", N
);
1944 -- Find the renamed entity that matches the given specification. Disable
1945 -- Ada_83 because there is no requirement of full conformance between
1946 -- renamed entity and new entity, even though the same circuit is used.
1948 -- This is a bit of a kludge, which introduces a really irregular use of
1949 -- Ada_Version[_Explicit]. Would be nice to find cleaner way to do this
1952 Ada_Version
:= Ada_Version_Type
'Max (Ada_Version
, Ada_95
);
1953 Ada_Version_Explicit
:= Ada_Version
;
1956 Old_S
:= Find_Renamed_Entity
(N
, Name
(N
), New_S
, Is_Actual
);
1958 -- When the renamed subprogram is overloaded and used as an actual
1959 -- of a generic, its entity is set to the first available homonym.
1960 -- We must first disambiguate the name, then set the proper entity.
1963 and then Is_Overloaded
(Nam
)
1965 Set_Entity
(Nam
, Old_S
);
1969 -- Most common case: subprogram renames subprogram. No body is generated
1970 -- in this case, so we must indicate the declaration is complete as is.
1971 -- and inherit various attributes of the renamed subprogram.
1973 if No
(Rename_Spec
) then
1974 Set_Has_Completion
(New_S
);
1975 Set_Is_Imported
(New_S
, Is_Imported
(Entity
(Nam
)));
1976 Set_Is_Pure
(New_S
, Is_Pure
(Entity
(Nam
)));
1977 Set_Is_Preelaborated
(New_S
, Is_Preelaborated
(Entity
(Nam
)));
1979 -- Ada 2005 (AI-423): Check the consistency of null exclusions
1980 -- between a subprogram and its correct renaming.
1982 -- Note: the Any_Id check is a guard that prevents compiler crashes
1983 -- when performing a null exclusion check between a renaming and a
1984 -- renamed subprogram that has been found to be illegal.
1986 if Ada_Version
>= Ada_05
1987 and then Entity
(Nam
) /= Any_Id
1989 Check_Null_Exclusion
1991 Sub
=> Entity
(Nam
));
1994 -- Enforce the Ada 2005 rule that the renamed entity cannot require
1995 -- overriding. The flag Requires_Overriding is set very selectively
1996 -- and misses some other illegal cases. The additional conditions
1997 -- checked below are sufficient but not necessary ???
1999 -- The rule does not apply to the renaming generated for an actual
2000 -- subprogram in an instance.
2005 -- Guard against previous errors, and omit renamings of predefined
2008 elsif Ekind
(Old_S
) /= E_Function
2009 and then Ekind
(Old_S
) /= E_Procedure
2013 elsif Requires_Overriding
(Old_S
)
2015 (Is_Abstract_Subprogram
(Old_S
)
2016 and then Present
(Find_Dispatching_Type
(Old_S
))
2018 not Is_Abstract_Type
(Find_Dispatching_Type
(Old_S
)))
2021 ("renamed entity cannot be "
2022 & "subprogram that requires overriding (RM 8.5.4 (5.1))", N
);
2026 if Old_S
/= Any_Id
then
2028 and then From_Default
(N
)
2030 -- This is an implicit reference to the default actual
2032 Generate_Reference
(Old_S
, Nam
, Typ
=> 'i', Force
=> True);
2034 Generate_Reference
(Old_S
, Nam
);
2037 -- For a renaming-as-body, require subtype conformance, but if the
2038 -- declaration being completed has not been frozen, then inherit the
2039 -- convention of the renamed subprogram prior to checking conformance
2040 -- (unless the renaming has an explicit convention established; the
2041 -- rule stated in the RM doesn't seem to address this ???).
2043 if Present
(Rename_Spec
) then
2044 Generate_Reference
(Rename_Spec
, Defining_Entity
(Spec
), 'b');
2045 Style
.Check_Identifier
(Defining_Entity
(Spec
), Rename_Spec
);
2047 if not Is_Frozen
(Rename_Spec
) then
2048 if not Has_Convention_Pragma
(Rename_Spec
) then
2049 Set_Convention
(New_S
, Convention
(Old_S
));
2052 if Ekind
(Old_S
) /= E_Operator
then
2053 Check_Mode_Conformant
(New_S
, Old_S
, Spec
);
2056 if Original_Subprogram
(Old_S
) = Rename_Spec
then
2057 Error_Msg_N
("unfrozen subprogram cannot rename itself ", N
);
2060 Check_Subtype_Conformant
(New_S
, Old_S
, Spec
);
2063 Check_Frozen_Renaming
(N
, Rename_Spec
);
2065 -- Check explicitly that renamed entity is not intrinsic, because
2066 -- in a generic the renamed body is not built. In this case,
2067 -- the renaming_as_body is a completion.
2069 if Inside_A_Generic
then
2070 if Is_Frozen
(Rename_Spec
)
2071 and then Is_Intrinsic_Subprogram
(Old_S
)
2074 ("subprogram in renaming_as_body cannot be intrinsic",
2078 Set_Has_Completion
(Rename_Spec
);
2081 elsif Ekind
(Old_S
) /= E_Operator
then
2082 Check_Mode_Conformant
(New_S
, Old_S
);
2085 and then Error_Posted
(New_S
)
2087 Error_Msg_NE
("invalid actual subprogram: & #!", N
, Old_S
);
2091 if No
(Rename_Spec
) then
2093 -- The parameter profile of the new entity is that of the renamed
2094 -- entity: the subtypes given in the specification are irrelevant.
2096 Inherit_Renamed_Profile
(New_S
, Old_S
);
2098 -- A call to the subprogram is transformed into a call to the
2099 -- renamed entity. This is transitive if the renamed entity is
2100 -- itself a renaming.
2102 if Present
(Alias
(Old_S
)) then
2103 Set_Alias
(New_S
, Alias
(Old_S
));
2105 Set_Alias
(New_S
, Old_S
);
2108 -- Note that we do not set Is_Intrinsic_Subprogram if we have a
2109 -- renaming as body, since the entity in this case is not an
2110 -- intrinsic (it calls an intrinsic, but we have a real body for
2111 -- this call, and it is in this body that the required intrinsic
2112 -- processing will take place).
2114 -- Also, if this is a renaming of inequality, the renamed operator
2115 -- is intrinsic, but what matters is the corresponding equality
2116 -- operator, which may be user-defined.
2118 Set_Is_Intrinsic_Subprogram
2120 Is_Intrinsic_Subprogram
(Old_S
)
2122 (Chars
(Old_S
) /= Name_Op_Ne
2123 or else Ekind
(Old_S
) = E_Operator
2125 Is_Intrinsic_Subprogram
2126 (Corresponding_Equality
(Old_S
))));
2128 if Ekind
(Alias
(New_S
)) = E_Operator
then
2129 Set_Has_Delayed_Freeze
(New_S
, False);
2132 -- If the renaming corresponds to an association for an abstract
2133 -- formal subprogram, then various attributes must be set to
2134 -- indicate that the renaming is an abstract dispatching operation
2135 -- with a controlling type.
2137 if Is_Actual
and then Is_Abstract_Subprogram
(Formal_Spec
) then
2139 -- Mark the renaming as abstract here, so Find_Dispatching_Type
2140 -- see it as corresponding to a generic association for a
2141 -- formal abstract subprogram
2143 Set_Is_Abstract_Subprogram
(New_S
);
2146 New_S_Ctrl_Type
: constant Entity_Id
:=
2147 Find_Dispatching_Type
(New_S
);
2148 Old_S_Ctrl_Type
: constant Entity_Id
:=
2149 Find_Dispatching_Type
(Old_S
);
2152 if Old_S_Ctrl_Type
/= New_S_Ctrl_Type
then
2154 ("actual must be dispatching subprogram for type&",
2155 Nam
, New_S_Ctrl_Type
);
2158 Set_Is_Dispatching_Operation
(New_S
);
2159 Check_Controlling_Formals
(New_S_Ctrl_Type
, New_S
);
2161 -- If the actual in the formal subprogram is itself a
2162 -- formal abstract subprogram association, there's no
2163 -- dispatch table component or position to inherit.
2165 if Present
(DTC_Entity
(Old_S
)) then
2166 Set_DTC_Entity
(New_S
, DTC_Entity
(Old_S
));
2167 Set_DT_Position
(New_S
, DT_Position
(Old_S
));
2175 and then (Old_S
= New_S
2176 or else (Nkind
(Nam
) /= N_Expanded_Name
2177 and then Chars
(Old_S
) = Chars
(New_S
)))
2179 Error_Msg_N
("subprogram cannot rename itself", N
);
2182 Set_Convention
(New_S
, Convention
(Old_S
));
2184 if Is_Abstract_Subprogram
(Old_S
) then
2185 if Present
(Rename_Spec
) then
2187 ("a renaming-as-body cannot rename an abstract subprogram",
2189 Set_Has_Completion
(Rename_Spec
);
2191 Set_Is_Abstract_Subprogram
(New_S
);
2195 Check_Library_Unit_Renaming
(N
, Old_S
);
2197 -- Pathological case: procedure renames entry in the scope of its
2198 -- task. Entry is given by simple name, but body must be built for
2199 -- procedure. Of course if called it will deadlock.
2201 if Ekind
(Old_S
) = E_Entry
then
2202 Set_Has_Completion
(New_S
, False);
2203 Set_Alias
(New_S
, Empty
);
2207 Freeze_Before
(N
, Old_S
);
2208 Set_Has_Delayed_Freeze
(New_S
, False);
2209 Freeze_Before
(N
, New_S
);
2211 -- An abstract subprogram is only allowed as an actual in the case
2212 -- where the formal subprogram is also abstract.
2214 if (Ekind
(Old_S
) = E_Procedure
or else Ekind
(Old_S
) = E_Function
)
2215 and then Is_Abstract_Subprogram
(Old_S
)
2216 and then not Is_Abstract_Subprogram
(Formal_Spec
)
2219 ("abstract subprogram not allowed as generic actual", Nam
);
2224 -- A common error is to assume that implicit operators for types are
2225 -- defined in Standard, or in the scope of a subtype. In those cases
2226 -- where the renamed entity is given with an expanded name, it is
2227 -- worth mentioning that operators for the type are not declared in
2228 -- the scope given by the prefix.
2230 if Nkind
(Nam
) = N_Expanded_Name
2231 and then Nkind
(Selector_Name
(Nam
)) = N_Operator_Symbol
2232 and then Scope
(Entity
(Nam
)) = Standard_Standard
2235 T
: constant Entity_Id
:=
2236 Base_Type
(Etype
(First_Formal
(New_S
)));
2238 Error_Msg_Node_2
:= Prefix
(Nam
);
2240 ("operator for type& is not declared in&", Prefix
(Nam
), T
);
2245 ("no visible subprogram matches the specification for&",
2249 if Present
(Candidate_Renaming
) then
2255 F1
:= First_Formal
(Candidate_Renaming
);
2256 F2
:= First_Formal
(New_S
);
2258 while Present
(F1
) and then Present
(F2
) loop
2263 if Present
(F1
) and then Present
(Default_Value
(F1
)) then
2264 if Present
(Next_Formal
(F1
)) then
2266 ("\missing specification for &" &
2267 " and other formals with defaults", Spec
, F1
);
2270 ("\missing specification for &", Spec
, F1
);
2277 -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that
2278 -- controlling access parameters are known non-null for the renamed
2279 -- subprogram. Test also applies to a subprogram instantiation that
2280 -- is dispatching. Test is skipped if some previous error was detected
2281 -- that set Old_S to Any_Id.
2283 if Ada_Version
>= Ada_05
2284 and then Old_S
/= Any_Id
2285 and then not Is_Dispatching_Operation
(Old_S
)
2286 and then Is_Dispatching_Operation
(New_S
)
2293 Old_F
:= First_Formal
(Old_S
);
2294 New_F
:= First_Formal
(New_S
);
2295 while Present
(Old_F
) loop
2296 if Ekind
(Etype
(Old_F
)) = E_Anonymous_Access_Type
2297 and then Is_Controlling_Formal
(New_F
)
2298 and then not Can_Never_Be_Null
(Old_F
)
2300 Error_Msg_N
("access parameter is controlling,", New_F
);
2302 ("\corresponding parameter of& "
2303 & "must be explicitly null excluding", New_F
, Old_S
);
2306 Next_Formal
(Old_F
);
2307 Next_Formal
(New_F
);
2312 -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005)
2314 if Comes_From_Source
(N
)
2315 and then Present
(Old_S
)
2316 and then Nkind
(Old_S
) = N_Defining_Operator_Symbol
2317 and then Nkind
(New_S
) = N_Defining_Operator_Symbol
2318 and then Chars
(Old_S
) /= Chars
(New_S
)
2321 ("?& is being renamed as a different operator",
2325 -- Another warning or some utility: if the new subprogram as the same
2326 -- name as the old one, the old one is not hidden by an outer homograph,
2327 -- the new one is not a public symbol, and the old one is otherwise
2328 -- directly visible, the renaming is superfluous.
2330 if Chars
(Old_S
) = Chars
(New_S
)
2331 and then Comes_From_Source
(N
)
2332 and then Scope
(Old_S
) /= Standard_Standard
2333 and then Warn_On_Redundant_Constructs
2335 (Is_Immediately_Visible
(Old_S
)
2336 or else Is_Potentially_Use_Visible
(Old_S
))
2337 and then Is_Overloadable
(Current_Scope
)
2338 and then Chars
(Current_Scope
) /= Chars
(Old_S
)
2341 ("?redundant renaming, entity is directly visible", Name
(N
));
2344 Ada_Version
:= Save_AV
;
2345 Ada_Version_Explicit
:= Save_AV_Exp
;
2346 end Analyze_Subprogram_Renaming
;
2348 -------------------------
2349 -- Analyze_Use_Package --
2350 -------------------------
2352 -- Resolve the package names in the use clause, and make all the visible
2353 -- entities defined in the package potentially use-visible. If the package
2354 -- is already in use from a previous use clause, its visible entities are
2355 -- already use-visible. In that case, mark the occurrence as a redundant
2356 -- use. If the package is an open scope, i.e. if the use clause occurs
2357 -- within the package itself, ignore it.
2359 procedure Analyze_Use_Package
(N
: Node_Id
) is
2360 Pack_Name
: Node_Id
;
2363 -- Start of processing for Analyze_Use_Package
2366 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
2368 -- Use clause is not allowed in a spec of a predefined package
2369 -- declaration except that packages whose file name starts a-n are OK
2370 -- (these are children of Ada.Numerics, and such packages are never
2371 -- loaded by Rtsfind).
2373 if Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
2374 and then Name_Buffer
(1 .. 3) /= "a-n"
2376 Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
2378 Error_Msg_N
("use clause not allowed in predefined spec", N
);
2381 -- Chain clause to list of use clauses in current scope
2383 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
2384 Chain_Use_Clause
(N
);
2387 -- Loop through package names to identify referenced packages
2389 Pack_Name
:= First
(Names
(N
));
2390 while Present
(Pack_Name
) loop
2391 Analyze
(Pack_Name
);
2393 if Nkind
(Parent
(N
)) = N_Compilation_Unit
2394 and then Nkind
(Pack_Name
) = N_Expanded_Name
2400 Pref
:= Prefix
(Pack_Name
);
2401 while Nkind
(Pref
) = N_Expanded_Name
loop
2402 Pref
:= Prefix
(Pref
);
2405 if Entity
(Pref
) = Standard_Standard
then
2407 ("predefined package Standard cannot appear"
2408 & " in a context clause", Pref
);
2416 -- Loop through package names to mark all entities as potentially
2419 Pack_Name
:= First
(Names
(N
));
2420 while Present
(Pack_Name
) loop
2421 if Is_Entity_Name
(Pack_Name
) then
2422 Pack
:= Entity
(Pack_Name
);
2424 if Ekind
(Pack
) /= E_Package
2425 and then Etype
(Pack
) /= Any_Type
2427 if Ekind
(Pack
) = E_Generic_Package
then
2429 ("a generic package is not allowed in a use clause",
2432 Error_Msg_N
("& is not a usable package", Pack_Name
);
2436 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
2437 Check_In_Previous_With_Clause
(N
, Pack_Name
);
2440 if Applicable_Use
(Pack_Name
) then
2441 Use_One_Package
(Pack
, N
);
2445 -- Report error because name denotes something other than a package
2448 Error_Msg_N
("& is not a package", Pack_Name
);
2453 end Analyze_Use_Package
;
2455 ----------------------
2456 -- Analyze_Use_Type --
2457 ----------------------
2459 procedure Analyze_Use_Type
(N
: Node_Id
) is
2464 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
2466 -- Chain clause to list of use clauses in current scope
2468 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
2469 Chain_Use_Clause
(N
);
2472 Id
:= First
(Subtype_Marks
(N
));
2473 while Present
(Id
) loop
2477 if E
/= Any_Type
then
2480 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
2481 if Nkind
(Id
) = N_Identifier
then
2482 Error_Msg_N
("type is not directly visible", Id
);
2484 elsif Is_Child_Unit
(Scope
(E
))
2485 and then Scope
(E
) /= System_Aux_Id
2487 Check_In_Previous_With_Clause
(N
, Prefix
(Id
));
2494 end Analyze_Use_Type
;
2496 --------------------
2497 -- Applicable_Use --
2498 --------------------
2500 function Applicable_Use
(Pack_Name
: Node_Id
) return Boolean is
2501 Pack
: constant Entity_Id
:= Entity
(Pack_Name
);
2504 if In_Open_Scopes
(Pack
) then
2505 if Warn_On_Redundant_Constructs
2506 and then Pack
= Current_Scope
2509 ("& is already use-visible within itself?", Pack_Name
, Pack
);
2514 elsif In_Use
(Pack
) then
2515 Note_Redundant_Use
(Pack_Name
);
2518 elsif Present
(Renamed_Object
(Pack
))
2519 and then In_Use
(Renamed_Object
(Pack
))
2521 Note_Redundant_Use
(Pack_Name
);
2529 ------------------------
2530 -- Attribute_Renaming --
2531 ------------------------
2533 procedure Attribute_Renaming
(N
: Node_Id
) is
2534 Loc
: constant Source_Ptr
:= Sloc
(N
);
2535 Nam
: constant Node_Id
:= Name
(N
);
2536 Spec
: constant Node_Id
:= Specification
(N
);
2537 New_S
: constant Entity_Id
:= Defining_Unit_Name
(Spec
);
2538 Aname
: constant Name_Id
:= Attribute_Name
(Nam
);
2540 Form_Num
: Nat
:= 0;
2541 Expr_List
: List_Id
:= No_List
;
2543 Attr_Node
: Node_Id
;
2544 Body_Node
: Node_Id
;
2545 Param_Spec
: Node_Id
;
2548 Generate_Definition
(New_S
);
2550 -- This procedure is called in the context of subprogram renaming,
2551 -- and thus the attribute must be one that is a subprogram. All of
2552 -- those have at least one formal parameter, with the singular
2553 -- exception of AST_Entry (which is a real oddity, it is odd that
2554 -- this can be renamed at all!)
2556 if not Is_Non_Empty_List
(Parameter_Specifications
(Spec
)) then
2557 if Aname
/= Name_AST_Entry
then
2559 ("subprogram renaming an attribute must have formals", N
);
2564 Param_Spec
:= First
(Parameter_Specifications
(Spec
));
2565 while Present
(Param_Spec
) loop
2566 Form_Num
:= Form_Num
+ 1;
2568 if Nkind
(Parameter_Type
(Param_Spec
)) /= N_Access_Definition
then
2569 Find_Type
(Parameter_Type
(Param_Spec
));
2571 -- The profile of the new entity denotes the base type (s) of
2572 -- the types given in the specification. For access parameters
2573 -- there are no subtypes involved.
2575 Rewrite
(Parameter_Type
(Param_Spec
),
2577 (Base_Type
(Entity
(Parameter_Type
(Param_Spec
))), Loc
));
2580 if No
(Expr_List
) then
2581 Expr_List
:= New_List
;
2584 Append_To
(Expr_List
,
2585 Make_Identifier
(Loc
,
2586 Chars
=> Chars
(Defining_Identifier
(Param_Spec
))));
2588 -- The expressions in the attribute reference are not freeze
2589 -- points. Neither is the attribute as a whole, see below.
2591 Set_Must_Not_Freeze
(Last
(Expr_List
));
2596 -- Immediate error if too many formals. Other mismatches in numbers
2597 -- of number of types of parameters are detected when we analyze the
2598 -- body of the subprogram that we construct.
2600 if Form_Num
> 2 then
2601 Error_Msg_N
("too many formals for attribute", N
);
2603 -- Error if the attribute reference has expressions that look
2604 -- like formal parameters.
2606 elsif Present
(Expressions
(Nam
)) then
2607 Error_Msg_N
("illegal expressions in attribute reference", Nam
);
2610 Aname
= Name_Compose
or else
2611 Aname
= Name_Exponent
or else
2612 Aname
= Name_Leading_Part
or else
2613 Aname
= Name_Pos
or else
2614 Aname
= Name_Round
or else
2615 Aname
= Name_Scaling
or else
2618 if Nkind
(N
) = N_Subprogram_Renaming_Declaration
2619 and then Present
(Corresponding_Formal_Spec
(N
))
2622 ("generic actual cannot be attribute involving universal type",
2626 ("attribute involving a universal type cannot be renamed",
2631 -- AST_Entry is an odd case. It doesn't really make much sense to
2632 -- allow it to be renamed, but that's the DEC rule, so we have to
2633 -- do it right. The point is that the AST_Entry call should be made
2634 -- now, and what the function will return is the returned value.
2636 -- Note that there is no Expr_List in this case anyway
2638 if Aname
= Name_AST_Entry
then
2644 Ent
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('R'));
2647 Make_Object_Declaration
(Loc
,
2648 Defining_Identifier
=> Ent
,
2649 Object_Definition
=>
2650 New_Occurrence_Of
(RTE
(RE_AST_Handler
), Loc
),
2652 Constant_Present
=> True);
2654 Set_Assignment_OK
(Decl
, True);
2655 Insert_Action
(N
, Decl
);
2656 Attr_Node
:= Make_Identifier
(Loc
, Chars
(Ent
));
2659 -- For all other attributes, we rewrite the attribute node to have
2660 -- a list of expressions corresponding to the subprogram formals.
2661 -- A renaming declaration is not a freeze point, and the analysis of
2662 -- the attribute reference should not freeze the type of the prefix.
2666 Make_Attribute_Reference
(Loc
,
2667 Prefix
=> Prefix
(Nam
),
2668 Attribute_Name
=> Aname
,
2669 Expressions
=> Expr_List
);
2671 Set_Must_Not_Freeze
(Attr_Node
);
2672 Set_Must_Not_Freeze
(Prefix
(Nam
));
2675 -- Case of renaming a function
2677 if Nkind
(Spec
) = N_Function_Specification
then
2678 if Is_Procedure_Attribute_Name
(Aname
) then
2679 Error_Msg_N
("attribute can only be renamed as procedure", Nam
);
2683 Find_Type
(Result_Definition
(Spec
));
2684 Rewrite
(Result_Definition
(Spec
),
2686 Base_Type
(Entity
(Result_Definition
(Spec
))), Loc
));
2689 Make_Subprogram_Body
(Loc
,
2690 Specification
=> Spec
,
2691 Declarations
=> New_List
,
2692 Handled_Statement_Sequence
=>
2693 Make_Handled_Sequence_Of_Statements
(Loc
,
2694 Statements
=> New_List
(
2695 Make_Simple_Return_Statement
(Loc
,
2696 Expression
=> Attr_Node
))));
2698 -- Case of renaming a procedure
2701 if not Is_Procedure_Attribute_Name
(Aname
) then
2702 Error_Msg_N
("attribute can only be renamed as function", Nam
);
2707 Make_Subprogram_Body
(Loc
,
2708 Specification
=> Spec
,
2709 Declarations
=> New_List
,
2710 Handled_Statement_Sequence
=>
2711 Make_Handled_Sequence_Of_Statements
(Loc
,
2712 Statements
=> New_List
(Attr_Node
)));
2715 -- In case of tagged types we add the body of the generated function to
2716 -- the freezing actions of the type (because in the general case such
2717 -- type is still not frozen). We exclude from this processing generic
2718 -- formal subprograms found in instantiations and AST_Entry renamings.
2720 if not Present
(Corresponding_Formal_Spec
(N
))
2721 and then Etype
(Nam
) /= RTE
(RE_AST_Handler
)
2724 P
: constant Entity_Id
:= Prefix
(Nam
);
2729 if Is_Tagged_Type
(Etype
(P
)) then
2730 Ensure_Freeze_Node
(Etype
(P
));
2731 Append_Freeze_Action
(Etype
(P
), Body_Node
);
2733 Rewrite
(N
, Body_Node
);
2735 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
2739 -- Generic formal subprograms or AST_Handler renaming
2742 Rewrite
(N
, Body_Node
);
2744 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
2747 if Is_Compilation_Unit
(New_S
) then
2749 ("a library unit can only rename another library unit", N
);
2752 -- We suppress elaboration warnings for the resulting entity, since
2753 -- clearly they are not needed, and more particularly, in the case
2754 -- of a generic formal subprogram, the resulting entity can appear
2755 -- after the instantiation itself, and thus look like a bogus case
2756 -- of access before elaboration.
2758 Set_Suppress_Elaboration_Warnings
(New_S
);
2760 end Attribute_Renaming
;
2762 ----------------------
2763 -- Chain_Use_Clause --
2764 ----------------------
2766 procedure Chain_Use_Clause
(N
: Node_Id
) is
2768 Level
: Int
:= Scope_Stack
.Last
;
2771 if not Is_Compilation_Unit
(Current_Scope
)
2772 or else not Is_Child_Unit
(Current_Scope
)
2774 null; -- Common case
2776 elsif Defining_Entity
(Parent
(N
)) = Current_Scope
then
2777 null; -- Common case for compilation unit
2780 -- If declaration appears in some other scope, it must be in some
2781 -- parent unit when compiling a child.
2783 Pack
:= Defining_Entity
(Parent
(N
));
2784 if not In_Open_Scopes
(Pack
) then
2785 null; -- default as well
2788 -- Find entry for parent unit in scope stack
2790 while Scope_Stack
.Table
(Level
).Entity
/= Pack
loop
2796 Set_Next_Use_Clause
(N
,
2797 Scope_Stack
.Table
(Level
).First_Use_Clause
);
2798 Scope_Stack
.Table
(Level
).First_Use_Clause
:= N
;
2799 end Chain_Use_Clause
;
2801 ---------------------------
2802 -- Check_Frozen_Renaming --
2803 ---------------------------
2805 procedure Check_Frozen_Renaming
(N
: Node_Id
; Subp
: Entity_Id
) is
2811 and then not Has_Completion
(Subp
)
2815 (Parent
(Declaration_Node
(Subp
)), Defining_Entity
(N
));
2817 if Is_Entity_Name
(Name
(N
)) then
2818 Old_S
:= Entity
(Name
(N
));
2820 if not Is_Frozen
(Old_S
)
2821 and then Operating_Mode
/= Check_Semantics
2823 Append_Freeze_Action
(Old_S
, B_Node
);
2825 Insert_After
(N
, B_Node
);
2829 if Is_Intrinsic_Subprogram
(Old_S
)
2830 and then not In_Instance
2833 ("subprogram used in renaming_as_body cannot be intrinsic",
2838 Insert_After
(N
, B_Node
);
2842 end Check_Frozen_Renaming
;
2844 -----------------------------------
2845 -- Check_In_Previous_With_Clause --
2846 -----------------------------------
2848 procedure Check_In_Previous_With_Clause
2852 Pack
: constant Entity_Id
:= Entity
(Original_Node
(Nam
));
2857 Item
:= First
(Context_Items
(Parent
(N
)));
2859 while Present
(Item
)
2862 if Nkind
(Item
) = N_With_Clause
2864 -- Protect the frontend against previous critical errors
2866 and then Nkind
(Name
(Item
)) /= N_Selected_Component
2867 and then Entity
(Name
(Item
)) = Pack
2871 -- Find root library unit in with_clause
2873 while Nkind
(Par
) = N_Expanded_Name
loop
2874 Par
:= Prefix
(Par
);
2877 if Is_Child_Unit
(Entity
(Original_Node
(Par
))) then
2879 ("& is not directly visible", Par
, Entity
(Par
));
2888 -- On exit, package is not mentioned in a previous with_clause.
2889 -- Check if its prefix is.
2891 if Nkind
(Nam
) = N_Expanded_Name
then
2892 Check_In_Previous_With_Clause
(N
, Prefix
(Nam
));
2894 elsif Pack
/= Any_Id
then
2895 Error_Msg_NE
("& is not visible", Nam
, Pack
);
2897 end Check_In_Previous_With_Clause
;
2899 ---------------------------------
2900 -- Check_Library_Unit_Renaming --
2901 ---------------------------------
2903 procedure Check_Library_Unit_Renaming
(N
: Node_Id
; Old_E
: Entity_Id
) is
2907 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
2910 -- Check for library unit. Note that we used to check for the scope
2911 -- being Standard here, but that was wrong for Standard itself.
2913 elsif not Is_Compilation_Unit
(Old_E
)
2914 and then not Is_Child_Unit
(Old_E
)
2916 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
2918 -- Entities defined in Standard (operators and boolean literals) cannot
2919 -- be renamed as library units.
2921 elsif Scope
(Old_E
) = Standard_Standard
2922 and then Sloc
(Old_E
) = Standard_Location
2924 Error_Msg_N
("renamed unit must be a library unit", Name
(N
));
2926 elsif Present
(Parent_Spec
(N
))
2927 and then Nkind
(Unit
(Parent_Spec
(N
))) = N_Generic_Package_Declaration
2928 and then not Is_Child_Unit
(Old_E
)
2931 ("renamed unit must be a child unit of generic parent", Name
(N
));
2933 elsif Nkind
(N
) in N_Generic_Renaming_Declaration
2934 and then Nkind
(Name
(N
)) = N_Expanded_Name
2935 and then Is_Generic_Instance
(Entity
(Prefix
(Name
(N
))))
2936 and then Is_Generic_Unit
(Old_E
)
2939 ("renamed generic unit must be a library unit", Name
(N
));
2941 elsif Is_Package_Or_Generic_Package
(Old_E
) then
2943 -- Inherit categorization flags
2945 New_E
:= Defining_Entity
(N
);
2946 Set_Is_Pure
(New_E
, Is_Pure
(Old_E
));
2947 Set_Is_Preelaborated
(New_E
, Is_Preelaborated
(Old_E
));
2948 Set_Is_Remote_Call_Interface
(New_E
,
2949 Is_Remote_Call_Interface
(Old_E
));
2950 Set_Is_Remote_Types
(New_E
, Is_Remote_Types
(Old_E
));
2951 Set_Is_Shared_Passive
(New_E
, Is_Shared_Passive
(Old_E
));
2953 end Check_Library_Unit_Renaming
;
2959 procedure End_Scope
is
2965 Id
:= First_Entity
(Current_Scope
);
2966 while Present
(Id
) loop
2967 -- An entity in the current scope is not necessarily the first one
2968 -- on its homonym chain. Find its predecessor if any,
2969 -- If it is an internal entity, it will not be in the visibility
2970 -- chain altogether, and there is nothing to unchain.
2972 if Id
/= Current_Entity
(Id
) then
2973 Prev
:= Current_Entity
(Id
);
2974 while Present
(Prev
)
2975 and then Present
(Homonym
(Prev
))
2976 and then Homonym
(Prev
) /= Id
2978 Prev
:= Homonym
(Prev
);
2981 -- Skip to end of loop if Id is not in the visibility chain
2983 if No
(Prev
) or else Homonym
(Prev
) /= Id
then
2991 Set_Is_Immediately_Visible
(Id
, False);
2993 Outer
:= Homonym
(Id
);
2994 while Present
(Outer
) and then Scope
(Outer
) = Current_Scope
loop
2995 Outer
:= Homonym
(Outer
);
2998 -- Reset homonym link of other entities, but do not modify link
2999 -- between entities in current scope, so that the back-end can have
3000 -- a proper count of local overloadings.
3003 Set_Name_Entity_Id
(Chars
(Id
), Outer
);
3005 elsif Scope
(Prev
) /= Scope
(Id
) then
3006 Set_Homonym
(Prev
, Outer
);
3013 -- If the scope generated freeze actions, place them before the
3014 -- current declaration and analyze them. Type declarations and
3015 -- the bodies of initialization procedures can generate such nodes.
3016 -- We follow the parent chain until we reach a list node, which is
3017 -- the enclosing list of declarations. If the list appears within
3018 -- a protected definition, move freeze nodes outside the protected
3022 (Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
)
3026 L
: constant List_Id
:= Scope_Stack
.Table
3027 (Scope_Stack
.Last
).Pending_Freeze_Actions
;
3030 if Is_Itype
(Current_Scope
) then
3031 Decl
:= Associated_Node_For_Itype
(Current_Scope
);
3033 Decl
:= Parent
(Current_Scope
);
3038 while not (Is_List_Member
(Decl
))
3039 or else Nkind_In
(Parent
(Decl
), N_Protected_Definition
,
3042 Decl
:= Parent
(Decl
);
3045 Insert_List_Before_And_Analyze
(Decl
, L
);
3054 ---------------------
3055 -- End_Use_Clauses --
3056 ---------------------
3058 procedure End_Use_Clauses
(Clause
: Node_Id
) is
3062 -- Remove Use_Type clauses first, because they affect the
3063 -- visibility of operators in subsequent used packages.
3066 while Present
(U
) loop
3067 if Nkind
(U
) = N_Use_Type_Clause
then
3071 Next_Use_Clause
(U
);
3075 while Present
(U
) loop
3076 if Nkind
(U
) = N_Use_Package_Clause
then
3077 End_Use_Package
(U
);
3080 Next_Use_Clause
(U
);
3082 end End_Use_Clauses
;
3084 ---------------------
3085 -- End_Use_Package --
3086 ---------------------
3088 procedure End_Use_Package
(N
: Node_Id
) is
3089 Pack_Name
: Node_Id
;
3094 function Is_Primitive_Operator
3096 F
: Entity_Id
) return Boolean;
3097 -- Check whether Op is a primitive operator of a use-visible type
3099 ---------------------------
3100 -- Is_Primitive_Operator --
3101 ---------------------------
3103 function Is_Primitive_Operator
3105 F
: Entity_Id
) return Boolean
3107 T
: constant Entity_Id
:= Etype
(F
);
3110 and then Scope
(T
) = Scope
(Op
);
3111 end Is_Primitive_Operator
;
3113 -- Start of processing for End_Use_Package
3116 Pack_Name
:= First
(Names
(N
));
3117 while Present
(Pack_Name
) loop
3119 -- Test that Pack_Name actually denotes a package before processing
3121 if Is_Entity_Name
(Pack_Name
)
3122 and then Ekind
(Entity
(Pack_Name
)) = E_Package
3124 Pack
:= Entity
(Pack_Name
);
3126 if In_Open_Scopes
(Pack
) then
3129 elsif not Redundant_Use
(Pack_Name
) then
3130 Set_In_Use
(Pack
, False);
3131 Set_Current_Use_Clause
(Pack
, Empty
);
3133 Id
:= First_Entity
(Pack
);
3134 while Present
(Id
) loop
3136 -- Preserve use-visibility of operators that are primitive
3137 -- operators of a type that is use-visible through an active
3140 if Nkind
(Id
) = N_Defining_Operator_Symbol
3142 (Is_Primitive_Operator
(Id
, First_Formal
(Id
))
3144 (Present
(Next_Formal
(First_Formal
(Id
)))
3146 Is_Primitive_Operator
3147 (Id
, Next_Formal
(First_Formal
(Id
)))))
3152 Set_Is_Potentially_Use_Visible
(Id
, False);
3155 if Is_Private_Type
(Id
)
3156 and then Present
(Full_View
(Id
))
3158 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
3164 if Present
(Renamed_Object
(Pack
)) then
3165 Set_In_Use
(Renamed_Object
(Pack
), False);
3166 Set_Current_Use_Clause
(Renamed_Object
(Pack
), Empty
);
3169 if Chars
(Pack
) = Name_System
3170 and then Scope
(Pack
) = Standard_Standard
3171 and then Present_System_Aux
3173 Id
:= First_Entity
(System_Aux_Id
);
3174 while Present
(Id
) loop
3175 Set_Is_Potentially_Use_Visible
(Id
, False);
3177 if Is_Private_Type
(Id
)
3178 and then Present
(Full_View
(Id
))
3180 Set_Is_Potentially_Use_Visible
(Full_View
(Id
), False);
3186 Set_In_Use
(System_Aux_Id
, False);
3190 Set_Redundant_Use
(Pack_Name
, False);
3197 if Present
(Hidden_By_Use_Clause
(N
)) then
3198 Elmt
:= First_Elmt
(Hidden_By_Use_Clause
(N
));
3199 while Present
(Elmt
) loop
3200 Set_Is_Immediately_Visible
(Node
(Elmt
));
3204 Set_Hidden_By_Use_Clause
(N
, No_Elist
);
3206 end End_Use_Package
;
3212 procedure End_Use_Type
(N
: Node_Id
) is
3219 Id
:= First
(Subtype_Marks
(N
));
3220 while Present
(Id
) loop
3222 -- A call to rtsfind may occur while analyzing a use_type clause,
3223 -- in which case the type marks are not resolved yet, and there is
3224 -- nothing to remove.
3226 if not Is_Entity_Name
(Id
)
3227 or else No
(Entity
(Id
))
3235 or else From_With_Type
(T
)
3239 -- Note that the use_Type clause may mention a subtype of the type
3240 -- whose primitive operations have been made visible. Here as
3241 -- elsewhere, it is the base type that matters for visibility.
3243 elsif In_Open_Scopes
(Scope
(Base_Type
(T
))) then
3246 elsif not Redundant_Use
(Id
) then
3247 Set_In_Use
(T
, False);
3248 Set_In_Use
(Base_Type
(T
), False);
3249 Set_Current_Use_Clause
(T
, Empty
);
3250 Set_Current_Use_Clause
(Base_Type
(T
), Empty
);
3251 Op_List
:= Collect_Primitive_Operations
(T
);
3253 Elmt
:= First_Elmt
(Op_List
);
3254 while Present
(Elmt
) loop
3255 if Nkind
(Node
(Elmt
)) = N_Defining_Operator_Symbol
then
3256 Set_Is_Potentially_Use_Visible
(Node
(Elmt
), False);
3268 ----------------------
3269 -- Find_Direct_Name --
3270 ----------------------
3272 procedure Find_Direct_Name
(N
: Node_Id
) is
3277 Inst
: Entity_Id
:= Empty
;
3278 -- Enclosing instance, if any
3280 Homonyms
: Entity_Id
;
3281 -- Saves start of homonym chain
3283 Nvis_Entity
: Boolean;
3284 -- Set True to indicate that at there is at least one entity on the
3285 -- homonym chain which, while not visible, is visible enough from the
3286 -- user point of view to warrant an error message of "not visible"
3287 -- rather than undefined.
3289 Nvis_Is_Private_Subprg
: Boolean := False;
3290 -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais
3291 -- effect concerning library subprograms has been detected. Used to
3292 -- generate the precise error message.
3294 function From_Actual_Package
(E
: Entity_Id
) return Boolean;
3295 -- Returns true if the entity is declared in a package that is
3296 -- an actual for a formal package of the current instance. Such an
3297 -- entity requires special handling because it may be use-visible
3298 -- but hides directly visible entities defined outside the instance.
3300 function Is_Actual_Parameter
return Boolean;
3301 -- This function checks if the node N is an identifier that is an actual
3302 -- parameter of a procedure call. If so it returns True, otherwise it
3303 -- return False. The reason for this check is that at this stage we do
3304 -- not know what procedure is being called if the procedure might be
3305 -- overloaded, so it is premature to go setting referenced flags or
3306 -- making calls to Generate_Reference. We will wait till Resolve_Actuals
3307 -- for that processing
3309 function Known_But_Invisible
(E
: Entity_Id
) return Boolean;
3310 -- This function determines whether the entity E (which is not
3311 -- visible) can reasonably be considered to be known to the writer
3312 -- of the reference. This is a heuristic test, used only for the
3313 -- purposes of figuring out whether we prefer to complain that an
3314 -- entity is undefined or invisible (and identify the declaration
3315 -- of the invisible entity in the latter case). The point here is
3316 -- that we don't want to complain that something is invisible and
3317 -- then point to something entirely mysterious to the writer.
3319 procedure Nvis_Messages
;
3320 -- Called if there are no visible entries for N, but there is at least
3321 -- one non-directly visible, or hidden declaration. This procedure
3322 -- outputs an appropriate set of error messages.
3324 procedure Undefined
(Nvis
: Boolean);
3325 -- This function is called if the current node has no corresponding
3326 -- visible entity or entities. The value set in Msg indicates whether
3327 -- an error message was generated (multiple error messages for the
3328 -- same variable are generally suppressed, see body for details).
3329 -- Msg is True if an error message was generated, False if not. This
3330 -- value is used by the caller to determine whether or not to output
3331 -- additional messages where appropriate. The parameter is set False
3332 -- to get the message "X is undefined", and True to get the message
3333 -- "X is not visible".
3335 -------------------------
3336 -- From_Actual_Package --
3337 -------------------------
3339 function From_Actual_Package
(E
: Entity_Id
) return Boolean is
3340 Scop
: constant Entity_Id
:= Scope
(E
);
3344 if not In_Instance
then
3347 Inst
:= Current_Scope
;
3348 while Present
(Inst
)
3349 and then Ekind
(Inst
) /= E_Package
3350 and then not Is_Generic_Instance
(Inst
)
3352 Inst
:= Scope
(Inst
);
3359 Act
:= First_Entity
(Inst
);
3360 while Present
(Act
) loop
3361 if Ekind
(Act
) = E_Package
then
3363 -- Check for end of actuals list
3365 if Renamed_Object
(Act
) = Inst
then
3368 elsif Present
(Associated_Formal_Package
(Act
))
3369 and then Renamed_Object
(Act
) = Scop
3371 -- Entity comes from (instance of) formal package
3386 end From_Actual_Package
;
3388 -------------------------
3389 -- Is_Actual_Parameter --
3390 -------------------------
3392 function Is_Actual_Parameter
return Boolean is
3395 Nkind
(N
) = N_Identifier
3397 (Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
3399 (Nkind
(Parent
(N
)) = N_Parameter_Association
3400 and then N
= Explicit_Actual_Parameter
(Parent
(N
))
3401 and then Nkind
(Parent
(Parent
(N
))) =
3402 N_Procedure_Call_Statement
));
3403 end Is_Actual_Parameter
;
3405 -------------------------
3406 -- Known_But_Invisible --
3407 -------------------------
3409 function Known_But_Invisible
(E
: Entity_Id
) return Boolean is
3410 Fname
: File_Name_Type
;
3413 -- Entities in Standard are always considered to be known
3415 if Sloc
(E
) <= Standard_Location
then
3418 -- An entity that does not come from source is always considered
3419 -- to be unknown, since it is an artifact of code expansion.
3421 elsif not Comes_From_Source
(E
) then
3424 -- In gnat internal mode, we consider all entities known
3426 elsif GNAT_Mode
then
3430 -- Here we have an entity that is not from package Standard, and
3431 -- which comes from Source. See if it comes from an internal file.
3433 Fname
:= Unit_File_Name
(Get_Source_Unit
(E
));
3435 -- Case of from internal file
3437 if Is_Internal_File_Name
(Fname
) then
3439 -- Private part entities in internal files are never considered
3440 -- to be known to the writer of normal application code.
3442 if Is_Hidden
(E
) then
3446 -- Entities from System packages other than System and
3447 -- System.Storage_Elements are not considered to be known.
3448 -- System.Auxxxx files are also considered known to the user.
3450 -- Should refine this at some point to generally distinguish
3451 -- between known and unknown internal files ???
3453 Get_Name_String
(Fname
);
3458 Name_Buffer
(1 .. 2) /= "s-"
3460 Name_Buffer
(3 .. 8) = "stoele"
3462 Name_Buffer
(3 .. 5) = "aux";
3464 -- If not an internal file, then entity is definitely known,
3465 -- even if it is in a private part (the message generated will
3466 -- note that it is in a private part)
3471 end Known_But_Invisible
;
3477 procedure Nvis_Messages
is
3478 Comp_Unit
: Node_Id
;
3480 Hidden
: Boolean := False;
3484 -- Ada 2005 (AI-262): Generate a precise error concerning the
3485 -- Beaujolais effect that was previously detected
3487 if Nvis_Is_Private_Subprg
then
3489 pragma Assert
(Nkind
(E2
) = N_Defining_Identifier
3490 and then Ekind
(E2
) = E_Function
3491 and then Scope
(E2
) = Standard_Standard
3492 and then Has_Private_With
(E2
));
3494 -- Find the sloc corresponding to the private with'ed unit
3496 Comp_Unit
:= Cunit
(Current_Sem_Unit
);
3497 Error_Msg_Sloc
:= No_Location
;
3499 Item
:= First
(Context_Items
(Comp_Unit
));
3500 while Present
(Item
) loop
3501 if Nkind
(Item
) = N_With_Clause
3502 and then Private_Present
(Item
)
3503 and then Entity
(Name
(Item
)) = E2
3505 Error_Msg_Sloc
:= Sloc
(Item
);
3512 pragma Assert
(Error_Msg_Sloc
/= No_Location
);
3514 Error_Msg_N
("(Ada 2005): hidden by private with clause #", N
);
3518 Undefined
(Nvis
=> True);
3522 -- First loop does hidden declarations
3525 while Present
(Ent
) loop
3526 if Is_Potentially_Use_Visible
(Ent
) then
3528 Error_Msg_N
("multiple use clauses cause hiding!", N
);
3532 Error_Msg_Sloc
:= Sloc
(Ent
);
3533 Error_Msg_N
("hidden declaration#!", N
);
3536 Ent
:= Homonym
(Ent
);
3539 -- If we found hidden declarations, then that's enough, don't
3540 -- bother looking for non-visible declarations as well.
3546 -- Second loop does non-directly visible declarations
3549 while Present
(Ent
) loop
3550 if not Is_Potentially_Use_Visible
(Ent
) then
3552 -- Do not bother the user with unknown entities
3554 if not Known_But_Invisible
(Ent
) then
3558 Error_Msg_Sloc
:= Sloc
(Ent
);
3560 -- Output message noting that there is a non-visible
3561 -- declaration, distinguishing the private part case.
3563 if Is_Hidden
(Ent
) then
3564 Error_Msg_N
("non-visible (private) declaration#!", N
);
3566 Error_Msg_N
("non-visible declaration#!", N
);
3568 if Is_Compilation_Unit
(Ent
)
3570 Nkind
(Parent
(Parent
(N
))) = N_Use_Package_Clause
3572 Error_Msg_Qual_Level
:= 99;
3573 Error_Msg_NE
("\\missing `WITH &;`", N
, Ent
);
3574 Error_Msg_Qual_Level
:= 0;
3578 -- Set entity and its containing package as referenced. We
3579 -- can't be sure of this, but this seems a better choice
3580 -- to avoid unused entity messages.
3582 if Comes_From_Source
(Ent
) then
3583 Set_Referenced
(Ent
);
3584 Set_Referenced
(Cunit_Entity
(Get_Source_Unit
(Ent
)));
3589 Ent
:= Homonym
(Ent
);
3598 procedure Undefined
(Nvis
: Boolean) is
3599 Emsg
: Error_Msg_Id
;
3602 -- We should never find an undefined internal name. If we do, then
3603 -- see if we have previous errors. If so, ignore on the grounds that
3604 -- it is probably a cascaded message (e.g. a block label from a badly
3605 -- formed block). If no previous errors, then we have a real internal
3606 -- error of some kind so raise an exception.
3608 if Is_Internal_Name
(Chars
(N
)) then
3609 if Total_Errors_Detected
/= 0 then
3612 raise Program_Error
;
3616 -- A very specialized error check, if the undefined variable is
3617 -- a case tag, and the case type is an enumeration type, check
3618 -- for a possible misspelling, and if so, modify the identifier
3620 -- Named aggregate should also be handled similarly ???
3622 if Nkind
(N
) = N_Identifier
3623 and then Nkind
(Parent
(N
)) = N_Case_Statement_Alternative
3626 Case_Stm
: constant Node_Id
:= Parent
(Parent
(N
));
3627 Case_Typ
: constant Entity_Id
:= Etype
(Expression
(Case_Stm
));
3632 if Is_Enumeration_Type
(Case_Typ
)
3633 and then not Is_Standard_Character_Type
(Case_Typ
)
3635 Lit
:= First_Literal
(Case_Typ
);
3636 Get_Name_String
(Chars
(Lit
));
3638 if Chars
(Lit
) /= Chars
(N
)
3639 and then Is_Bad_Spelling_Of
(Chars
(N
), Chars
(Lit
)) then
3640 Error_Msg_Node_2
:= Lit
;
3642 ("& is undefined, assume misspelling of &", N
);
3643 Rewrite
(N
, New_Occurrence_Of
(Lit
, Sloc
(N
)));
3647 Lit
:= Next_Literal
(Lit
);
3652 -- Normal processing
3654 Set_Entity
(N
, Any_Id
);
3655 Set_Etype
(N
, Any_Type
);
3657 -- We use the table Urefs to keep track of entities for which we
3658 -- have issued errors for undefined references. Multiple errors
3659 -- for a single name are normally suppressed, however we modify
3660 -- the error message to alert the programmer to this effect.
3662 for J
in Urefs
.First
.. Urefs
.Last
loop
3663 if Chars
(N
) = Chars
(Urefs
.Table
(J
).Node
) then
3664 if Urefs
.Table
(J
).Err
/= No_Error_Msg
3665 and then Sloc
(N
) /= Urefs
.Table
(J
).Loc
3667 Error_Msg_Node_1
:= Urefs
.Table
(J
).Node
;
3669 if Urefs
.Table
(J
).Nvis
then
3670 Change_Error_Text
(Urefs
.Table
(J
).Err
,
3671 "& is not visible (more references follow)");
3673 Change_Error_Text
(Urefs
.Table
(J
).Err
,
3674 "& is undefined (more references follow)");
3677 Urefs
.Table
(J
).Err
:= No_Error_Msg
;
3680 -- Although we will set Msg False, and thus suppress the
3681 -- message, we also set Error_Posted True, to avoid any
3682 -- cascaded messages resulting from the undefined reference.
3685 Set_Error_Posted
(N
, True);
3690 -- If entry not found, this is first undefined occurrence
3693 Error_Msg_N
("& is not visible!", N
);
3697 Error_Msg_N
("& is undefined!", N
);
3700 -- A very bizarre special check, if the undefined identifier
3701 -- is put or put_line, then add a special error message (since
3702 -- this is a very common error for beginners to make).
3704 if Chars
(N
) = Name_Put
or else Chars
(N
) = Name_Put_Line
then
3706 ("\\possible missing `WITH Ada.Text_'I'O; " &
3707 "USE Ada.Text_'I'O`!", N
);
3709 -- Another special check if N is the prefix of a selected
3710 -- component which is a known unit, add message complaining
3711 -- about missing with for this unit.
3713 elsif Nkind
(Parent
(N
)) = N_Selected_Component
3714 and then N
= Prefix
(Parent
(N
))
3715 and then Is_Known_Unit
(Parent
(N
))
3717 Error_Msg_Node_2
:= Selector_Name
(Parent
(N
));
3718 Error_Msg_N
("\\missing `WITH &.&;`", Prefix
(Parent
(N
)));
3721 -- Now check for possible misspellings
3725 Ematch
: Entity_Id
:= Empty
;
3727 Last_Name_Id
: constant Name_Id
:=
3728 Name_Id
(Nat
(First_Name_Id
) +
3729 Name_Entries_Count
- 1);
3732 for Nam
in First_Name_Id
.. Last_Name_Id
loop
3733 E
:= Get_Name_Entity_Id
(Nam
);
3736 and then (Is_Immediately_Visible
(E
)
3738 Is_Potentially_Use_Visible
(E
))
3740 if Is_Bad_Spelling_Of
(Chars
(N
), Nam
) then
3747 if Present
(Ematch
) then
3748 Error_Msg_NE
("\possible misspelling of&", N
, Ematch
);
3753 -- Make entry in undefined references table unless the full errors
3754 -- switch is set, in which case by refraining from generating the
3755 -- table entry, we guarantee that we get an error message for every
3756 -- undefined reference.
3758 if not All_Errors_Mode
then
3769 -- Start of processing for Find_Direct_Name
3772 -- If the entity pointer is already set, this is an internal node, or
3773 -- a node that is analyzed more than once, after a tree modification.
3774 -- In such a case there is no resolution to perform, just set the type.
3776 if Present
(Entity
(N
)) then
3777 if Is_Type
(Entity
(N
)) then
3778 Set_Etype
(N
, Entity
(N
));
3782 Entyp
: constant Entity_Id
:= Etype
(Entity
(N
));
3785 -- One special case here. If the Etype field is already set,
3786 -- and references the packed array type corresponding to the
3787 -- etype of the referenced entity, then leave it alone. This
3788 -- happens for trees generated from Exp_Pakd, where expressions
3789 -- can be deliberately "mis-typed" to the packed array type.
3791 if Is_Array_Type
(Entyp
)
3792 and then Is_Packed
(Entyp
)
3793 and then Present
(Etype
(N
))
3794 and then Etype
(N
) = Packed_Array_Type
(Entyp
)
3798 -- If not that special case, then just reset the Etype
3801 Set_Etype
(N
, Etype
(Entity
(N
)));
3809 -- Here if Entity pointer was not set, we need full visibility analysis
3810 -- First we generate debugging output if the debug E flag is set.
3812 if Debug_Flag_E
then
3813 Write_Str
("Looking for ");
3814 Write_Name
(Chars
(N
));
3818 Homonyms
:= Current_Entity
(N
);
3819 Nvis_Entity
:= False;
3822 while Present
(E
) loop
3824 -- If entity is immediately visible or potentially use visible, then
3825 -- process the entity and we are done.
3827 if Is_Immediately_Visible
(E
) then
3828 goto Immediately_Visible_Entity
;
3830 elsif Is_Potentially_Use_Visible
(E
) then
3831 goto Potentially_Use_Visible_Entity
;
3833 -- Note if a known but invisible entity encountered
3835 elsif Known_But_Invisible
(E
) then
3836 Nvis_Entity
:= True;
3839 -- Move to next entity in chain and continue search
3844 -- If no entries on homonym chain that were potentially visible,
3845 -- and no entities reasonably considered as non-visible, then
3846 -- we have a plain undefined reference, with no additional
3847 -- explanation required!
3849 if not Nvis_Entity
then
3850 Undefined
(Nvis
=> False);
3852 -- Otherwise there is at least one entry on the homonym chain that
3853 -- is reasonably considered as being known and non-visible.
3861 -- Processing for a potentially use visible entry found. We must search
3862 -- the rest of the homonym chain for two reasons. First, if there is a
3863 -- directly visible entry, then none of the potentially use-visible
3864 -- entities are directly visible (RM 8.4(10)). Second, we need to check
3865 -- for the case of multiple potentially use-visible entries hiding one
3866 -- another and as a result being non-directly visible (RM 8.4(11)).
3868 <<Potentially_Use_Visible_Entity
>> declare
3869 Only_One_Visible
: Boolean := True;
3870 All_Overloadable
: Boolean := Is_Overloadable
(E
);
3874 while Present
(E2
) loop
3875 if Is_Immediately_Visible
(E2
) then
3877 -- If the use-visible entity comes from the actual for a
3878 -- formal package, it hides a directly visible entity from
3879 -- outside the instance.
3881 if From_Actual_Package
(E
)
3882 and then Scope_Depth
(E2
) < Scope_Depth
(Inst
)
3887 goto Immediately_Visible_Entity
;
3890 elsif Is_Potentially_Use_Visible
(E2
) then
3891 Only_One_Visible
:= False;
3892 All_Overloadable
:= All_Overloadable
and Is_Overloadable
(E2
);
3894 -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect
3895 -- that can occur in private_with clauses. Example:
3898 -- private with B; package A is
3899 -- package C is function B return Integer;
3901 -- V1 : Integer := B;
3902 -- private function B return Integer;
3903 -- V2 : Integer := B;
3906 -- V1 resolves to A.B, but V2 resolves to library unit B
3908 elsif Ekind
(E2
) = E_Function
3909 and then Scope
(E2
) = Standard_Standard
3910 and then Has_Private_With
(E2
)
3912 Only_One_Visible
:= False;
3913 All_Overloadable
:= False;
3914 Nvis_Is_Private_Subprg
:= True;
3921 -- On falling through this loop, we have checked that there are no
3922 -- immediately visible entities. Only_One_Visible is set if exactly
3923 -- one potentially use visible entity exists. All_Overloadable is
3924 -- set if all the potentially use visible entities are overloadable.
3925 -- The condition for legality is that either there is one potentially
3926 -- use visible entity, or if there is more than one, then all of them
3927 -- are overloadable.
3929 if Only_One_Visible
or All_Overloadable
then
3932 -- If there is more than one potentially use-visible entity and at
3933 -- least one of them non-overloadable, we have an error (RM 8.4(11).
3934 -- Note that E points to the first such entity on the homonym list.
3935 -- Special case: if one of the entities is declared in an actual
3936 -- package, it was visible in the generic, and takes precedence over
3937 -- other entities that are potentially use-visible. Same if it is
3938 -- declared in a local instantiation of the current instance.
3943 -- Find current instance
3945 Inst
:= Current_Scope
;
3946 while Present
(Inst
)
3947 and then Inst
/= Standard_Standard
3949 if Is_Generic_Instance
(Inst
) then
3953 Inst
:= Scope
(Inst
);
3957 while Present
(E2
) loop
3958 if From_Actual_Package
(E2
)
3960 (Is_Generic_Instance
(Scope
(E2
))
3961 and then Scope_Depth
(Scope
(E2
)) > Scope_Depth
(Inst
))
3974 Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
3976 -- A use-clause in the body of a system file creates conflict
3977 -- with some entity in a user scope, while rtsfind is active.
3978 -- Keep only the entity coming from another predefined unit.
3981 while Present
(E2
) loop
3982 if Is_Predefined_File_Name
3983 (Unit_File_Name
(Get_Source_Unit
(Sloc
(E2
))))
3992 -- Entity must exist because predefined unit is correct
3994 raise Program_Error
;
4003 -- Come here with E set to the first immediately visible entity on
4004 -- the homonym chain. This is the one we want unless there is another
4005 -- immediately visible entity further on in the chain for an inner
4006 -- scope (RM 8.3(8)).
4008 <<Immediately_Visible_Entity
>> declare
4013 -- Find scope level of initial entity. When compiling through
4014 -- Rtsfind, the previous context is not completely invisible, and
4015 -- an outer entity may appear on the chain, whose scope is below
4016 -- the entry for Standard that delimits the current scope stack.
4017 -- Indicate that the level for this spurious entry is outside of
4018 -- the current scope stack.
4020 Level
:= Scope_Stack
.Last
;
4022 Scop
:= Scope_Stack
.Table
(Level
).Entity
;
4023 exit when Scop
= Scope
(E
);
4025 exit when Scop
= Standard_Standard
;
4028 -- Now search remainder of homonym chain for more inner entry
4029 -- If the entity is Standard itself, it has no scope, and we
4030 -- compare it with the stack entry directly.
4033 while Present
(E2
) loop
4034 if Is_Immediately_Visible
(E2
) then
4036 -- If a generic package contains a local declaration that
4037 -- has the same name as the generic, there may be a visibility
4038 -- conflict in an instance, where the local declaration must
4039 -- also hide the name of the corresponding package renaming.
4040 -- We check explicitly for a package declared by a renaming,
4041 -- whose renamed entity is an instance that is on the scope
4042 -- stack, and that contains a homonym in the same scope. Once
4043 -- we have found it, we know that the package renaming is not
4044 -- immediately visible, and that the identifier denotes the
4045 -- other entity (and its homonyms if overloaded).
4047 if Scope
(E
) = Scope
(E2
)
4048 and then Ekind
(E
) = E_Package
4049 and then Present
(Renamed_Object
(E
))
4050 and then Is_Generic_Instance
(Renamed_Object
(E
))
4051 and then In_Open_Scopes
(Renamed_Object
(E
))
4052 and then Comes_From_Source
(N
)
4054 Set_Is_Immediately_Visible
(E
, False);
4058 for J
in Level
+ 1 .. Scope_Stack
.Last
loop
4059 if Scope_Stack
.Table
(J
).Entity
= Scope
(E2
)
4060 or else Scope_Stack
.Table
(J
).Entity
= E2
4073 -- At the end of that loop, E is the innermost immediately
4074 -- visible entity, so we are all set.
4077 -- Come here with entity found, and stored in E
4081 -- When distribution features are available (Get_PCS_Name /=
4082 -- Name_No_DSA), a remote access-to-subprogram type is converted
4083 -- into a record type holding whatever information is needed to
4084 -- perform a remote call on an RCI subprogram. In that case we
4085 -- rewrite any occurrence of the RAS type into the equivalent record
4086 -- type here. 'Access attribute references and RAS dereferences are
4087 -- then implemented using specific TSSs. However when distribution is
4088 -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the
4089 -- generation of these TSSs, and we must keep the RAS type in its
4090 -- original access-to-subprogram form (since all calls through a
4091 -- value of such type will be local anyway in the absence of a PCS).
4093 if Comes_From_Source
(N
)
4094 and then Is_Remote_Access_To_Subprogram_Type
(E
)
4095 and then Expander_Active
4096 and then Get_PCS_Name
/= Name_No_DSA
4099 New_Occurrence_Of
(Equivalent_Type
(E
), Sloc
(N
)));
4104 -- Why no Style_Check here???
4109 Set_Etype
(N
, Get_Full_View
(Etype
(E
)));
4112 if Debug_Flag_E
then
4113 Write_Str
(" found ");
4114 Write_Entity_Info
(E
, " ");
4117 -- If the Ekind of the entity is Void, it means that all homonyms
4118 -- are hidden from all visibility (RM 8.3(5,14-20)). However, this
4119 -- test is skipped if the current scope is a record and the name is
4120 -- a pragma argument expression (case of Atomic and Volatile pragmas
4121 -- and possibly other similar pragmas added later, which are allowed
4122 -- to reference components in the current record).
4124 if Ekind
(E
) = E_Void
4126 (not Is_Record_Type
(Current_Scope
)
4127 or else Nkind
(Parent
(N
)) /= N_Pragma_Argument_Association
)
4129 Premature_Usage
(N
);
4131 -- If the entity is overloadable, collect all interpretations of the
4132 -- name for subsequent overload resolution. We optimize a bit here to
4133 -- do this only if we have an overloadable entity that is not on its
4134 -- own on the homonym chain.
4136 elsif Is_Overloadable
(E
)
4137 and then (Present
(Homonym
(E
)) or else Current_Entity
(N
) /= E
)
4139 Collect_Interps
(N
);
4141 -- If no homonyms were visible, the entity is unambiguous
4143 if not Is_Overloaded
(N
) then
4144 if not Is_Actual_Parameter
then
4145 Generate_Reference
(E
, N
);
4149 -- Case of non-overloadable entity, set the entity providing that
4150 -- we do not have the case of a discriminant reference within a
4151 -- default expression. Such references are replaced with the
4152 -- corresponding discriminal, which is the formal corresponding to
4153 -- to the discriminant in the initialization procedure.
4156 -- Entity is unambiguous, indicate that it is referenced here
4158 -- For a renaming of an object, always generate simple reference,
4159 -- we don't try to keep track of assignments in this case.
4161 if Is_Object
(E
) and then Present
(Renamed_Object
(E
)) then
4162 Generate_Reference
(E
, N
);
4164 -- If the renamed entity is a private protected component,
4165 -- reference the original component as well. This needs to be
4166 -- done because the private renamings are installed before any
4167 -- analysis has occurred. Reference to a private component will
4168 -- resolve to the renaming and the original component will be
4169 -- left unreferenced, hence the following.
4171 if Is_Prival
(E
) then
4172 Generate_Reference
(Prival_Link
(E
), N
);
4175 -- One odd case is that we do not want to set the Referenced flag
4176 -- if the entity is a label, and the identifier is the label in
4177 -- the source, since this is not a reference from the point of
4178 -- view of the user.
4180 elsif Nkind
(Parent
(N
)) = N_Label
then
4182 R
: constant Boolean := Referenced
(E
);
4185 -- Generate reference unless this is an actual parameter
4186 -- (see comment below)
4188 if Is_Actual_Parameter
then
4189 Generate_Reference
(E
, N
);
4190 Set_Referenced
(E
, R
);
4194 -- Normal case, not a label: generate reference
4196 -- ??? It is too early to generate a reference here even if
4197 -- the entity is unambiguous, because the tree is not
4198 -- sufficiently typed at this point for Generate_Reference to
4199 -- determine whether this reference modifies the denoted object
4200 -- (because implicit dereferences cannot be identified prior to
4201 -- full type resolution).
4203 -- The Is_Actual_Parameter routine takes care of one of these
4204 -- cases but there are others probably ???
4207 if not Is_Actual_Parameter
then
4208 Generate_Reference
(E
, N
);
4211 Check_Nested_Access
(E
);
4214 -- Set Entity, with style check if need be. For a discriminant
4215 -- reference, replace by the corresponding discriminal, i.e. the
4216 -- parameter of the initialization procedure that corresponds to
4217 -- the discriminant. If this replacement is being performed, there
4218 -- is no style check to perform.
4220 -- This replacement must not be done if we are currently
4221 -- processing a generic spec or body, because the discriminal
4222 -- has not been not generated in this case.
4224 -- The replacement is also skipped if we are in special
4225 -- spec-expression mode. Why is this skipped in this case ???
4227 if not In_Spec_Expression
4228 or else Ekind
(E
) /= E_Discriminant
4229 or else Inside_A_Generic
4231 Set_Entity_With_Style_Check
(N
, E
);
4233 -- The replacement is not done either for a task discriminant that
4234 -- appears in a default expression of an entry parameter. See
4235 -- Expand_Discriminant in exp_ch2 for details on their handling.
4237 elsif Is_Concurrent_Type
(Scope
(E
)) then
4244 and then not Nkind_In
(P
, N_Parameter_Specification
,
4245 N_Component_Declaration
)
4251 and then Nkind
(P
) = N_Parameter_Specification
4255 Set_Entity
(N
, Discriminal
(E
));
4259 -- Otherwise, this is a discriminant in a context in which
4260 -- it is a reference to the corresponding parameter of the
4261 -- init proc for the enclosing type.
4264 Set_Entity
(N
, Discriminal
(E
));
4268 end Find_Direct_Name
;
4270 ------------------------
4271 -- Find_Expanded_Name --
4272 ------------------------
4274 -- This routine searches the homonym chain of the entity until it finds
4275 -- an entity declared in the scope denoted by the prefix. If the entity
4276 -- is private, it may nevertheless be immediately visible, if we are in
4277 -- the scope of its declaration.
4279 procedure Find_Expanded_Name
(N
: Node_Id
) is
4280 Selector
: constant Node_Id
:= Selector_Name
(N
);
4281 Candidate
: Entity_Id
:= Empty
;
4287 P_Name
:= Entity
(Prefix
(N
));
4290 -- If the prefix is a renamed package, look for the entity in the
4291 -- original package.
4293 if Ekind
(P_Name
) = E_Package
4294 and then Present
(Renamed_Object
(P_Name
))
4296 P_Name
:= Renamed_Object
(P_Name
);
4298 -- Rewrite node with entity field pointing to renamed object
4300 Rewrite
(Prefix
(N
), New_Copy
(Prefix
(N
)));
4301 Set_Entity
(Prefix
(N
), P_Name
);
4303 -- If the prefix is an object of a concurrent type, look for
4304 -- the entity in the associated task or protected type.
4306 elsif Is_Concurrent_Type
(Etype
(P_Name
)) then
4307 P_Name
:= Etype
(P_Name
);
4310 Id
:= Current_Entity
(Selector
);
4313 Is_New_Candidate
: Boolean;
4316 while Present
(Id
) loop
4317 if Scope
(Id
) = P_Name
then
4319 Is_New_Candidate
:= True;
4321 -- Ada 2005 (AI-217): Handle shadow entities associated with types
4322 -- declared in limited-withed nested packages. We don't need to
4323 -- handle E_Incomplete_Subtype entities because the entities in
4324 -- the limited view are always E_Incomplete_Type entities (see
4325 -- Build_Limited_Views). Regarding the expression used to evaluate
4326 -- the scope, it is important to note that the limited view also
4327 -- has shadow entities associated nested packages. For this reason
4328 -- the correct scope of the entity is the scope of the real entity
4329 -- The non-limited view may itself be incomplete, in which case
4330 -- get the full view if available.
4332 elsif From_With_Type
(Id
)
4333 and then Is_Type
(Id
)
4334 and then Ekind
(Id
) = E_Incomplete_Type
4335 and then Present
(Non_Limited_View
(Id
))
4336 and then Scope
(Non_Limited_View
(Id
)) = P_Name
4338 Candidate
:= Get_Full_View
(Non_Limited_View
(Id
));
4339 Is_New_Candidate
:= True;
4342 Is_New_Candidate
:= False;
4345 if Is_New_Candidate
then
4346 if Is_Child_Unit
(Id
) then
4347 exit when Is_Visible_Child_Unit
(Id
)
4348 or else Is_Immediately_Visible
(Id
);
4351 exit when not Is_Hidden
(Id
)
4352 or else Is_Immediately_Visible
(Id
);
4361 and then (Ekind
(P_Name
) = E_Procedure
4363 Ekind
(P_Name
) = E_Function
)
4364 and then Is_Generic_Instance
(P_Name
)
4366 -- Expanded name denotes entity in (instance of) generic subprogram.
4367 -- The entity may be in the subprogram instance, or may denote one of
4368 -- the formals, which is declared in the enclosing wrapper package.
4370 P_Name
:= Scope
(P_Name
);
4372 Id
:= Current_Entity
(Selector
);
4373 while Present
(Id
) loop
4374 exit when Scope
(Id
) = P_Name
;
4379 if No
(Id
) or else Chars
(Id
) /= Chars
(Selector
) then
4380 Set_Etype
(N
, Any_Type
);
4382 -- If we are looking for an entity defined in System, try to find it
4383 -- in the child package that may have been provided as an extension
4384 -- to System. The Extend_System pragma will have supplied the name of
4385 -- the extension, which may have to be loaded.
4387 if Chars
(P_Name
) = Name_System
4388 and then Scope
(P_Name
) = Standard_Standard
4389 and then Present
(System_Extend_Unit
)
4390 and then Present_System_Aux
(N
)
4392 Set_Entity
(Prefix
(N
), System_Aux_Id
);
4393 Find_Expanded_Name
(N
);
4396 elsif Nkind
(Selector
) = N_Operator_Symbol
4397 and then Has_Implicit_Operator
(N
)
4399 -- There is an implicit instance of the predefined operator in
4400 -- the given scope. The operator entity is defined in Standard.
4401 -- Has_Implicit_Operator makes the node into an Expanded_Name.
4405 elsif Nkind
(Selector
) = N_Character_Literal
4406 and then Has_Implicit_Character_Literal
(N
)
4408 -- If there is no literal defined in the scope denoted by the
4409 -- prefix, the literal may belong to (a type derived from)
4410 -- Standard_Character, for which we have no explicit literals.
4415 -- If the prefix is a single concurrent object, use its name in
4416 -- the error message, rather than that of the anonymous type.
4418 if Is_Concurrent_Type
(P_Name
)
4419 and then Is_Internal_Name
(Chars
(P_Name
))
4421 Error_Msg_Node_2
:= Entity
(Prefix
(N
));
4423 Error_Msg_Node_2
:= P_Name
;
4426 if P_Name
= System_Aux_Id
then
4427 P_Name
:= Scope
(P_Name
);
4428 Set_Entity
(Prefix
(N
), P_Name
);
4431 if Present
(Candidate
) then
4433 -- If we know that the unit is a child unit we can give a more
4434 -- accurate error message.
4436 if Is_Child_Unit
(Candidate
) then
4438 -- If the candidate is a private child unit and we are in
4439 -- the visible part of a public unit, specialize the error
4440 -- message. There might be a private with_clause for it,
4441 -- but it is not currently active.
4443 if Is_Private_Descendant
(Candidate
)
4444 and then Ekind
(Current_Scope
) = E_Package
4445 and then not In_Private_Part
(Current_Scope
)
4446 and then not Is_Private_Descendant
(Current_Scope
)
4448 Error_Msg_N
("private child unit& is not visible here",
4451 -- Normal case where we have a missing with for a child unit
4454 Error_Msg_Qual_Level
:= 99;
4455 Error_Msg_NE
("missing `WITH &;`", Selector
, Candidate
);
4456 Error_Msg_Qual_Level
:= 0;
4459 -- Here we don't know that this is a child unit
4462 Error_Msg_NE
("& is not a visible entity of&", N
, Selector
);
4466 -- Within the instantiation of a child unit, the prefix may
4467 -- denote the parent instance, but the selector has the name
4468 -- of the original child. Find whether we are within the
4469 -- corresponding instance, and get the proper entity, which
4470 -- can only be an enclosing scope.
4473 and then In_Open_Scopes
(P_Name
)
4474 and then Is_Generic_Instance
(P_Name
)
4477 S
: Entity_Id
:= Current_Scope
;
4481 for J
in reverse 0 .. Scope_Stack
.Last
loop
4482 S
:= Scope_Stack
.Table
(J
).Entity
;
4484 exit when S
= Standard_Standard
;
4486 if Ekind
(S
) = E_Function
4487 or else Ekind
(S
) = E_Package
4488 or else Ekind
(S
) = E_Procedure
4490 P
:= Generic_Parent
(Specification
4491 (Unit_Declaration_Node
(S
)));
4494 and then Chars
(Scope
(P
)) = Chars
(O_Name
)
4495 and then Chars
(P
) = Chars
(Selector
)
4506 -- If this is a selection from Ada, System or Interfaces, then
4507 -- we assume a missing with for the corresponding package.
4509 if Is_Known_Unit
(N
) then
4510 if not Error_Posted
(N
) then
4511 Error_Msg_Node_2
:= Selector
;
4512 Error_Msg_N
("missing `WITH &.&;`", Prefix
(N
));
4515 -- If this is a selection from a dummy package, then suppress
4516 -- the error message, of course the entity is missing if the
4517 -- package is missing!
4519 elsif Sloc
(Error_Msg_Node_2
) = No_Location
then
4522 -- Here we have the case of an undefined component
4525 Error_Msg_NE
("& not declared in&", N
, Selector
);
4527 -- Check for misspelling of some entity in prefix
4529 Id
:= First_Entity
(P_Name
);
4530 while Present
(Id
) loop
4531 if Is_Bad_Spelling_Of
(Chars
(Id
), Chars
(Selector
))
4532 and then not Is_Internal_Name
(Chars
(Id
))
4535 ("possible misspelling of&", Selector
, Id
);
4542 -- Specialize the message if this may be an instantiation
4543 -- of a child unit that was not mentioned in the context.
4545 if Nkind
(Parent
(N
)) = N_Package_Instantiation
4546 and then Is_Generic_Instance
(Entity
(Prefix
(N
)))
4547 and then Is_Compilation_Unit
4548 (Generic_Parent
(Parent
(Entity
(Prefix
(N
)))))
4550 Error_Msg_Node_2
:= Selector
;
4551 Error_Msg_N
("\missing `WITH &.&;`", Prefix
(N
));
4561 if Comes_From_Source
(N
)
4562 and then Is_Remote_Access_To_Subprogram_Type
(Id
)
4563 and then Present
(Equivalent_Type
(Id
))
4565 -- If we are not actually generating distribution code (i.e. the
4566 -- current PCS is the dummy non-distributed version), then the
4567 -- Equivalent_Type will be missing, and Id should be treated as
4568 -- a regular access-to-subprogram type.
4570 Id
:= Equivalent_Type
(Id
);
4571 Set_Chars
(Selector
, Chars
(Id
));
4574 -- Ada 2005 (AI-50217): Check usage of entities in limited withed units
4576 if Ekind
(P_Name
) = E_Package
4577 and then From_With_Type
(P_Name
)
4579 if From_With_Type
(Id
)
4580 or else Is_Type
(Id
)
4581 or else Ekind
(Id
) = E_Package
4586 ("limited withed package can only be used to access "
4587 & "incomplete types",
4592 if Is_Task_Type
(P_Name
)
4593 and then ((Ekind
(Id
) = E_Entry
4594 and then Nkind
(Parent
(N
)) /= N_Attribute_Reference
)
4596 (Ekind
(Id
) = E_Entry_Family
4598 Nkind
(Parent
(Parent
(N
))) /= N_Attribute_Reference
))
4600 -- It is an entry call after all, either to the current task (which
4601 -- will deadlock) or to an enclosing task.
4603 Analyze_Selected_Component
(N
);
4607 Change_Selected_Component_To_Expanded_Name
(N
);
4609 -- Do style check and generate reference, but skip both steps if this
4610 -- entity has homonyms, since we may not have the right homonym set yet.
4611 -- The proper homonym will be set during the resolve phase.
4613 if Has_Homonym
(Id
) then
4616 Set_Entity_With_Style_Check
(N
, Id
);
4617 Generate_Reference
(Id
, N
);
4620 if Is_Type
(Id
) then
4623 Set_Etype
(N
, Get_Full_View
(Etype
(Id
)));
4626 -- If the Ekind of the entity is Void, it means that all homonyms are
4627 -- hidden from all visibility (RM 8.3(5,14-20)).
4629 if Ekind
(Id
) = E_Void
then
4630 Premature_Usage
(N
);
4632 elsif Is_Overloadable
(Id
)
4633 and then Present
(Homonym
(Id
))
4636 H
: Entity_Id
:= Homonym
(Id
);
4639 while Present
(H
) loop
4640 if Scope
(H
) = Scope
(Id
)
4643 or else Is_Immediately_Visible
(H
))
4645 Collect_Interps
(N
);
4652 -- If an extension of System is present, collect possible explicit
4653 -- overloadings declared in the extension.
4655 if Chars
(P_Name
) = Name_System
4656 and then Scope
(P_Name
) = Standard_Standard
4657 and then Present
(System_Extend_Unit
)
4658 and then Present_System_Aux
(N
)
4660 H
:= Current_Entity
(Id
);
4662 while Present
(H
) loop
4663 if Scope
(H
) = System_Aux_Id
then
4664 Add_One_Interp
(N
, H
, Etype
(H
));
4673 if Nkind
(Selector_Name
(N
)) = N_Operator_Symbol
4674 and then Scope
(Id
) /= Standard_Standard
4676 -- In addition to user-defined operators in the given scope, there
4677 -- may be an implicit instance of the predefined operator. The
4678 -- operator (defined in Standard) is found in Has_Implicit_Operator,
4679 -- and added to the interpretations. Procedure Add_One_Interp will
4680 -- determine which hides which.
4682 if Has_Implicit_Operator
(N
) then
4686 end Find_Expanded_Name
;
4688 -------------------------
4689 -- Find_Renamed_Entity --
4690 -------------------------
4692 function Find_Renamed_Entity
4696 Is_Actual
: Boolean := False) return Entity_Id
4699 I1
: Interp_Index
:= 0; -- Suppress junk warnings
4705 function Enclosing_Instance
return Entity_Id
;
4706 -- If the renaming determines the entity for the default of a formal
4707 -- subprogram nested within another instance, choose the innermost
4708 -- candidate. This is because if the formal has a box, and we are within
4709 -- an enclosing instance where some candidate interpretations are local
4710 -- to this enclosing instance, we know that the default was properly
4711 -- resolved when analyzing the generic, so we prefer the local
4712 -- candidates to those that are external. This is not always the case
4713 -- but is a reasonable heuristic on the use of nested generics. The
4714 -- proper solution requires a full renaming model.
4716 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean;
4717 -- If the renamed entity is an implicit operator, check whether it is
4718 -- visible because its operand type is properly visible. This check
4719 -- applies to explicit renamed entities that appear in the source in a
4720 -- renaming declaration or a formal subprogram instance, but not to
4721 -- default generic actuals with a name.
4723 function Report_Overload
return Entity_Id
;
4724 -- List possible interpretations, and specialize message in the
4725 -- case of a generic actual.
4727 function Within
(Inner
, Outer
: Entity_Id
) return Boolean;
4728 -- Determine whether a candidate subprogram is defined within the
4729 -- enclosing instance. If yes, it has precedence over outer candidates.
4731 ------------------------
4732 -- Enclosing_Instance --
4733 ------------------------
4735 function Enclosing_Instance
return Entity_Id
is
4739 if not Is_Generic_Instance
(Current_Scope
)
4740 and then not Is_Actual
4745 S
:= Scope
(Current_Scope
);
4746 while S
/= Standard_Standard
loop
4747 if Is_Generic_Instance
(S
) then
4755 end Enclosing_Instance
;
4757 --------------------------
4758 -- Is_Visible_Operation --
4759 --------------------------
4761 function Is_Visible_Operation
(Op
: Entity_Id
) return Boolean is
4767 if Ekind
(Op
) /= E_Operator
4768 or else Scope
(Op
) /= Standard_Standard
4769 or else (In_Instance
4772 or else Present
(Enclosing_Instance
)))
4777 -- For a fixed point type operator, check the resulting type,
4778 -- because it may be a mixed mode integer * fixed operation.
4780 if Present
(Next_Formal
(First_Formal
(New_S
)))
4781 and then Is_Fixed_Point_Type
(Etype
(New_S
))
4783 Typ
:= Etype
(New_S
);
4785 Typ
:= Etype
(First_Formal
(New_S
));
4788 Btyp
:= Base_Type
(Typ
);
4790 if Nkind
(Nam
) /= N_Expanded_Name
then
4791 return (In_Open_Scopes
(Scope
(Btyp
))
4792 or else Is_Potentially_Use_Visible
(Btyp
)
4793 or else In_Use
(Btyp
)
4794 or else In_Use
(Scope
(Btyp
)));
4797 Scop
:= Entity
(Prefix
(Nam
));
4799 if Ekind
(Scop
) = E_Package
4800 and then Present
(Renamed_Object
(Scop
))
4802 Scop
:= Renamed_Object
(Scop
);
4805 -- Operator is visible if prefix of expanded name denotes
4806 -- scope of type, or else type is defined in System_Aux
4807 -- and the prefix denotes System.
4809 return Scope
(Btyp
) = Scop
4810 or else (Scope
(Btyp
) = System_Aux_Id
4811 and then Scope
(Scope
(Btyp
)) = Scop
);
4814 end Is_Visible_Operation
;
4820 function Within
(Inner
, Outer
: Entity_Id
) return Boolean is
4824 Sc
:= Scope
(Inner
);
4825 while Sc
/= Standard_Standard
loop
4836 ---------------------
4837 -- Report_Overload --
4838 ---------------------
4840 function Report_Overload
return Entity_Id
is
4844 ("ambiguous actual subprogram&, " &
4845 "possible interpretations:", N
, Nam
);
4848 ("ambiguous subprogram, " &
4849 "possible interpretations:", N
);
4852 List_Interps
(Nam
, N
);
4854 end Report_Overload
;
4856 -- Start of processing for Find_Renamed_Entry
4860 Candidate_Renaming
:= Empty
;
4862 if not Is_Overloaded
(Nam
) then
4863 if Entity_Matches_Spec
(Entity
(Nam
), New_S
)
4864 and then Is_Visible_Operation
(Entity
(Nam
))
4866 Old_S
:= Entity
(Nam
);
4869 Present
(First_Formal
(Entity
(Nam
)))
4870 and then Present
(First_Formal
(New_S
))
4871 and then (Base_Type
(Etype
(First_Formal
(Entity
(Nam
))))
4872 = Base_Type
(Etype
(First_Formal
(New_S
))))
4874 Candidate_Renaming
:= Entity
(Nam
);
4878 Get_First_Interp
(Nam
, Ind
, It
);
4879 while Present
(It
.Nam
) loop
4880 if Entity_Matches_Spec
(It
.Nam
, New_S
)
4881 and then Is_Visible_Operation
(It
.Nam
)
4883 if Old_S
/= Any_Id
then
4885 -- Note: The call to Disambiguate only happens if a
4886 -- previous interpretation was found, in which case I1
4887 -- has received a value.
4889 It1
:= Disambiguate
(Nam
, I1
, Ind
, Etype
(Old_S
));
4891 if It1
= No_Interp
then
4892 Inst
:= Enclosing_Instance
;
4894 if Present
(Inst
) then
4895 if Within
(It
.Nam
, Inst
) then
4897 elsif Within
(Old_S
, Inst
) then
4900 return Report_Overload
;
4904 return Report_Overload
;
4918 Present
(First_Formal
(It
.Nam
))
4919 and then Present
(First_Formal
(New_S
))
4920 and then (Base_Type
(Etype
(First_Formal
(It
.Nam
)))
4921 = Base_Type
(Etype
(First_Formal
(New_S
))))
4923 Candidate_Renaming
:= It
.Nam
;
4926 Get_Next_Interp
(Ind
, It
);
4929 Set_Entity
(Nam
, Old_S
);
4930 Set_Is_Overloaded
(Nam
, False);
4934 end Find_Renamed_Entity
;
4936 -----------------------------
4937 -- Find_Selected_Component --
4938 -----------------------------
4940 procedure Find_Selected_Component
(N
: Node_Id
) is
4941 P
: constant Node_Id
:= Prefix
(N
);
4944 -- Entity denoted by prefix
4954 if Nkind
(P
) = N_Error
then
4957 -- If the selector already has an entity, the node has been constructed
4958 -- in the course of expansion, and is known to be valid. Do not verify
4959 -- that it is defined for the type (it may be a private component used
4960 -- in the expansion of record equality).
4962 elsif Present
(Entity
(Selector_Name
(N
))) then
4964 or else Etype
(N
) = Any_Type
4967 Sel_Name
: constant Node_Id
:= Selector_Name
(N
);
4968 Selector
: constant Entity_Id
:= Entity
(Sel_Name
);
4972 Set_Etype
(Sel_Name
, Etype
(Selector
));
4974 if not Is_Entity_Name
(P
) then
4978 -- Build an actual subtype except for the first parameter
4979 -- of an init proc, where this actual subtype is by
4980 -- definition incorrect, since the object is uninitialized
4981 -- (and does not even have defined discriminants etc.)
4983 if Is_Entity_Name
(P
)
4984 and then Ekind
(Entity
(P
)) = E_Function
4986 Nam
:= New_Copy
(P
);
4988 if Is_Overloaded
(P
) then
4989 Save_Interps
(P
, Nam
);
4993 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
4995 Analyze_Selected_Component
(N
);
4998 elsif Ekind
(Selector
) = E_Component
4999 and then (not Is_Entity_Name
(P
)
5000 or else Chars
(Entity
(P
)) /= Name_uInit
)
5003 Build_Actual_Subtype_Of_Component
(
5004 Etype
(Selector
), N
);
5009 if No
(C_Etype
) then
5010 C_Etype
:= Etype
(Selector
);
5012 Insert_Action
(N
, C_Etype
);
5013 C_Etype
:= Defining_Identifier
(C_Etype
);
5016 Set_Etype
(N
, C_Etype
);
5019 -- If this is the name of an entry or protected operation, and
5020 -- the prefix is an access type, insert an explicit dereference,
5021 -- so that entry calls are treated uniformly.
5023 if Is_Access_Type
(Etype
(P
))
5024 and then Is_Concurrent_Type
(Designated_Type
(Etype
(P
)))
5027 New_P
: constant Node_Id
:=
5028 Make_Explicit_Dereference
(Sloc
(P
),
5029 Prefix
=> Relocate_Node
(P
));
5032 Set_Etype
(P
, Designated_Type
(Etype
(Prefix
(P
))));
5036 -- If the selected component appears within a default expression
5037 -- and it has an actual subtype, the pre-analysis has not yet
5038 -- completed its analysis, because Insert_Actions is disabled in
5039 -- that context. Within the init proc of the enclosing type we
5040 -- must complete this analysis, if an actual subtype was created.
5042 elsif Inside_Init_Proc
then
5044 Typ
: constant Entity_Id
:= Etype
(N
);
5045 Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
5047 if Nkind
(Decl
) = N_Subtype_Declaration
5048 and then not Analyzed
(Decl
)
5049 and then Is_List_Member
(Decl
)
5050 and then No
(Parent
(Decl
))
5053 Insert_Action
(N
, Decl
);
5060 elsif Is_Entity_Name
(P
) then
5061 P_Name
:= Entity
(P
);
5063 -- The prefix may denote an enclosing type which is the completion
5064 -- of an incomplete type declaration.
5066 if Is_Type
(P_Name
) then
5067 Set_Entity
(P
, Get_Full_View
(P_Name
));
5068 Set_Etype
(P
, Entity
(P
));
5069 P_Name
:= Entity
(P
);
5072 P_Type
:= Base_Type
(Etype
(P
));
5074 if Debug_Flag_E
then
5075 Write_Str
("Found prefix type to be ");
5076 Write_Entity_Info
(P_Type
, " "); Write_Eol
;
5079 -- First check for components of a record object (not the
5080 -- result of a call, which is handled below).
5082 if Is_Appropriate_For_Record
(P_Type
)
5083 and then not Is_Overloadable
(P_Name
)
5084 and then not Is_Type
(P_Name
)
5086 -- Selected component of record. Type checking will validate
5087 -- name of selector.
5088 -- ??? could we rewrite an implicit dereference into an explicit
5091 Analyze_Selected_Component
(N
);
5093 elsif Is_Appropriate_For_Entry_Prefix
(P_Type
)
5094 and then not In_Open_Scopes
(P_Name
)
5095 and then (not Is_Concurrent_Type
(Etype
(P_Name
))
5096 or else not In_Open_Scopes
(Etype
(P_Name
)))
5098 -- Call to protected operation or entry. Type checking is
5099 -- needed on the prefix.
5101 Analyze_Selected_Component
(N
);
5103 elsif (In_Open_Scopes
(P_Name
)
5104 and then Ekind
(P_Name
) /= E_Void
5105 and then not Is_Overloadable
(P_Name
))
5106 or else (Is_Concurrent_Type
(Etype
(P_Name
))
5107 and then In_Open_Scopes
(Etype
(P_Name
)))
5109 -- Prefix denotes an enclosing loop, block, or task, i.e. an
5110 -- enclosing construct that is not a subprogram or accept.
5112 Find_Expanded_Name
(N
);
5114 elsif Ekind
(P_Name
) = E_Package
then
5115 Find_Expanded_Name
(N
);
5117 elsif Is_Overloadable
(P_Name
) then
5119 -- The subprogram may be a renaming (of an enclosing scope) as
5120 -- in the case of the name of the generic within an instantiation.
5122 if (Ekind
(P_Name
) = E_Procedure
5123 or else Ekind
(P_Name
) = E_Function
)
5124 and then Present
(Alias
(P_Name
))
5125 and then Is_Generic_Instance
(Alias
(P_Name
))
5127 P_Name
:= Alias
(P_Name
);
5130 if Is_Overloaded
(P
) then
5132 -- The prefix must resolve to a unique enclosing construct
5135 Found
: Boolean := False;
5140 Get_First_Interp
(P
, Ind
, It
);
5141 while Present
(It
.Nam
) loop
5142 if In_Open_Scopes
(It
.Nam
) then
5145 "prefix must be unique enclosing scope", N
);
5146 Set_Entity
(N
, Any_Id
);
5147 Set_Etype
(N
, Any_Type
);
5156 Get_Next_Interp
(Ind
, It
);
5161 if In_Open_Scopes
(P_Name
) then
5162 Set_Entity
(P
, P_Name
);
5163 Set_Is_Overloaded
(P
, False);
5164 Find_Expanded_Name
(N
);
5167 -- If no interpretation as an expanded name is possible, it
5168 -- must be a selected component of a record returned by a
5169 -- function call. Reformat prefix as a function call, the rest
5170 -- is done by type resolution. If the prefix is procedure or
5171 -- entry, as is P.X; this is an error.
5173 if Ekind
(P_Name
) /= E_Function
5174 and then (not Is_Overloaded
(P
)
5176 Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
)
5178 -- Prefix may mention a package that is hidden by a local
5179 -- declaration: let the user know. Scan the full homonym
5180 -- chain, the candidate package may be anywhere on it.
5182 if Present
(Homonym
(Current_Entity
(P_Name
))) then
5184 P_Name
:= Current_Entity
(P_Name
);
5186 while Present
(P_Name
) loop
5187 exit when Ekind
(P_Name
) = E_Package
;
5188 P_Name
:= Homonym
(P_Name
);
5191 if Present
(P_Name
) then
5192 Error_Msg_Sloc
:= Sloc
(Entity
(Prefix
(N
)));
5195 ("package& is hidden by declaration#",
5198 Set_Entity
(Prefix
(N
), P_Name
);
5199 Find_Expanded_Name
(N
);
5202 P_Name
:= Entity
(Prefix
(N
));
5207 ("invalid prefix in selected component&", N
, P_Name
);
5208 Change_Selected_Component_To_Expanded_Name
(N
);
5209 Set_Entity
(N
, Any_Id
);
5210 Set_Etype
(N
, Any_Type
);
5213 Nam
:= New_Copy
(P
);
5214 Save_Interps
(P
, Nam
);
5216 Make_Function_Call
(Sloc
(P
), Name
=> Nam
));
5218 Analyze_Selected_Component
(N
);
5222 -- Remaining cases generate various error messages
5225 -- Format node as expanded name, to avoid cascaded errors
5227 Change_Selected_Component_To_Expanded_Name
(N
);
5228 Set_Entity
(N
, Any_Id
);
5229 Set_Etype
(N
, Any_Type
);
5231 -- Issue error message, but avoid this if error issued already.
5232 -- Use identifier of prefix if one is available.
5234 if P_Name
= Any_Id
then
5237 elsif Ekind
(P_Name
) = E_Void
then
5238 Premature_Usage
(P
);
5240 elsif Nkind
(P
) /= N_Attribute_Reference
then
5242 "invalid prefix in selected component&", P
);
5244 if Is_Access_Type
(P_Type
)
5245 and then Ekind
(Designated_Type
(P_Type
)) = E_Incomplete_Type
5248 ("\dereference must not be of an incomplete type " &
5254 "invalid prefix in selected component", P
);
5259 -- If prefix is not the name of an entity, it must be an expression,
5260 -- whose type is appropriate for a record. This is determined by
5263 Analyze_Selected_Component
(N
);
5265 end Find_Selected_Component
;
5271 procedure Find_Type
(N
: Node_Id
) is
5281 elsif Nkind
(N
) = N_Attribute_Reference
then
5283 -- Class attribute. This is not valid in Ada 83 mode, but we do not
5284 -- need to enforce that at this point, since the declaration of the
5285 -- tagged type in the prefix would have been flagged already.
5287 if Attribute_Name
(N
) = Name_Class
then
5288 Check_Restriction
(No_Dispatch
, N
);
5289 Find_Type
(Prefix
(N
));
5291 -- Propagate error from bad prefix
5293 if Etype
(Prefix
(N
)) = Any_Type
then
5294 Set_Entity
(N
, Any_Type
);
5295 Set_Etype
(N
, Any_Type
);
5299 T
:= Base_Type
(Entity
(Prefix
(N
)));
5301 -- Case where type is not known to be tagged. Its appearance in
5302 -- the prefix of the 'Class attribute indicates that the full view
5305 if not Is_Tagged_Type
(T
) then
5306 if Ekind
(T
) = E_Incomplete_Type
then
5308 -- It is legal to denote the class type of an incomplete
5309 -- type. The full type will have to be tagged, of course.
5310 -- In Ada 2005 this usage is declared obsolescent, so we
5311 -- warn accordingly.
5313 -- ??? This test is temporarily disabled (always False)
5314 -- because it causes an unwanted warning on GNAT sources
5315 -- (built with -gnatg, which includes Warn_On_Obsolescent_
5316 -- Feature). Once this issue is cleared in the sources, it
5319 if not Is_Tagged_Type
(T
)
5320 and then Ada_Version
>= Ada_05
5321 and then Warn_On_Obsolescent_Feature
5325 ("applying 'Class to an untagged incomplete type"
5326 & " is an obsolescent feature (RM J.11)", N
);
5329 Set_Is_Tagged_Type
(T
);
5330 Set_Primitive_Operations
(T
, New_Elmt_List
);
5331 Make_Class_Wide_Type
(T
);
5332 Set_Entity
(N
, Class_Wide_Type
(T
));
5333 Set_Etype
(N
, Class_Wide_Type
(T
));
5335 elsif Ekind
(T
) = E_Private_Type
5336 and then not Is_Generic_Type
(T
)
5337 and then In_Private_Part
(Scope
(T
))
5339 -- The Class attribute can be applied to an untagged private
5340 -- type fulfilled by a tagged type prior to the full type
5341 -- declaration (but only within the parent package's private
5342 -- part). Create the class-wide type now and check that the
5343 -- full type is tagged later during its analysis. Note that
5344 -- we do not mark the private type as tagged, unlike the
5345 -- case of incomplete types, because the type must still
5346 -- appear untagged to outside units.
5348 if No
(Class_Wide_Type
(T
)) then
5349 Make_Class_Wide_Type
(T
);
5352 Set_Entity
(N
, Class_Wide_Type
(T
));
5353 Set_Etype
(N
, Class_Wide_Type
(T
));
5356 -- Should we introduce a type Any_Tagged and use Wrong_Type
5357 -- here, it would be a bit more consistent???
5360 ("tagged type required, found}",
5361 Prefix
(N
), First_Subtype
(T
));
5362 Set_Entity
(N
, Any_Type
);
5366 -- Case of tagged type
5369 if Is_Concurrent_Type
(T
) then
5370 if No
(Corresponding_Record_Type
(Entity
(Prefix
(N
)))) then
5372 -- Previous error. Use current type, which at least
5373 -- provides some operations.
5375 C
:= Entity
(Prefix
(N
));
5378 C
:= Class_Wide_Type
5379 (Corresponding_Record_Type
(Entity
(Prefix
(N
))));
5383 C
:= Class_Wide_Type
(Entity
(Prefix
(N
)));
5386 Set_Entity_With_Style_Check
(N
, C
);
5387 Generate_Reference
(C
, N
);
5391 -- Base attribute, not allowed in Ada 83
5393 elsif Attribute_Name
(N
) = Name_Base
then
5394 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
5396 ("(Ada 83) Base attribute not allowed in subtype mark", N
);
5399 Find_Type
(Prefix
(N
));
5400 Typ
:= Entity
(Prefix
(N
));
5402 if Ada_Version
>= Ada_95
5403 and then not Is_Scalar_Type
(Typ
)
5404 and then not Is_Generic_Type
(Typ
)
5407 ("prefix of Base attribute must be scalar type",
5410 elsif Sloc
(Typ
) = Standard_Location
5411 and then Base_Type
(Typ
) = Typ
5412 and then Warn_On_Redundant_Constructs
5415 ("?redundant attribute, & is its own base type", N
, Typ
);
5418 T
:= Base_Type
(Typ
);
5420 -- Rewrite attribute reference with type itself (see similar
5421 -- processing in Analyze_Attribute, case Base). Preserve
5422 -- prefix if present, for other legality checks.
5424 if Nkind
(Prefix
(N
)) = N_Expanded_Name
then
5426 Make_Expanded_Name
(Sloc
(N
),
5428 Prefix
=> New_Copy
(Prefix
(Prefix
(N
))),
5429 Selector_Name
=> New_Reference_To
(T
, Sloc
(N
))));
5432 Rewrite
(N
, New_Reference_To
(T
, Sloc
(N
)));
5439 elsif Attribute_Name
(N
) = Name_Stub_Type
then
5441 -- This is handled in Analyze_Attribute
5445 -- All other attributes are invalid in a subtype mark
5448 Error_Msg_N
("invalid attribute in subtype mark", N
);
5454 if Is_Entity_Name
(N
) then
5455 T_Name
:= Entity
(N
);
5457 Error_Msg_N
("subtype mark required in this context", N
);
5458 Set_Etype
(N
, Any_Type
);
5462 if T_Name
= Any_Id
or else Etype
(N
) = Any_Type
then
5464 -- Undefined id. Make it into a valid type
5466 Set_Entity
(N
, Any_Type
);
5468 elsif not Is_Type
(T_Name
)
5469 and then T_Name
/= Standard_Void_Type
5471 Error_Msg_Sloc
:= Sloc
(T_Name
);
5472 Error_Msg_N
("subtype mark required in this context", N
);
5473 Error_Msg_NE
("\\found & declared#", N
, T_Name
);
5474 Set_Entity
(N
, Any_Type
);
5477 -- If the type is an incomplete type created to handle
5478 -- anonymous access components of a record type, then the
5479 -- incomplete type is the visible entity and subsequent
5480 -- references will point to it. Mark the original full
5481 -- type as referenced, to prevent spurious warnings.
5483 if Is_Incomplete_Type
(T_Name
)
5484 and then Present
(Full_View
(T_Name
))
5485 and then not Comes_From_Source
(T_Name
)
5487 Set_Referenced
(Full_View
(T_Name
));
5490 T_Name
:= Get_Full_View
(T_Name
);
5492 -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through
5493 -- limited-with clauses
5495 if From_With_Type
(T_Name
)
5496 and then Ekind
(T_Name
) in Incomplete_Kind
5497 and then Present
(Non_Limited_View
(T_Name
))
5498 and then Is_Interface
(Non_Limited_View
(T_Name
))
5500 T_Name
:= Non_Limited_View
(T_Name
);
5503 if In_Open_Scopes
(T_Name
) then
5504 if Ekind
(Base_Type
(T_Name
)) = E_Task_Type
then
5506 -- In Ada 2005, a task name can be used in an access
5507 -- definition within its own body.
5509 if Ada_Version
>= Ada_05
5510 and then Nkind
(Parent
(N
)) = N_Access_Definition
5512 Set_Entity
(N
, T_Name
);
5513 Set_Etype
(N
, T_Name
);
5518 ("task type cannot be used as type mark " &
5519 "within its own spec or body", N
);
5522 elsif Ekind
(Base_Type
(T_Name
)) = E_Protected_Type
then
5524 -- In Ada 2005, a protected name can be used in an access
5525 -- definition within its own body.
5527 if Ada_Version
>= Ada_05
5528 and then Nkind
(Parent
(N
)) = N_Access_Definition
5530 Set_Entity
(N
, T_Name
);
5531 Set_Etype
(N
, T_Name
);
5536 ("protected type cannot be used as type mark " &
5537 "within its own spec or body", N
);
5541 Error_Msg_N
("type declaration cannot refer to itself", N
);
5544 Set_Etype
(N
, Any_Type
);
5545 Set_Entity
(N
, Any_Type
);
5546 Set_Error_Posted
(T_Name
);
5550 Set_Entity
(N
, T_Name
);
5551 Set_Etype
(N
, T_Name
);
5555 if Present
(Etype
(N
)) and then Comes_From_Source
(N
) then
5556 if Is_Fixed_Point_Type
(Etype
(N
)) then
5557 Check_Restriction
(No_Fixed_Point
, N
);
5558 elsif Is_Floating_Point_Type
(Etype
(N
)) then
5559 Check_Restriction
(No_Floating_Point
, N
);
5564 ------------------------------------
5565 -- Has_Implicit_Character_Literal --
5566 ------------------------------------
5568 function Has_Implicit_Character_Literal
(N
: Node_Id
) return Boolean is
5570 Found
: Boolean := False;
5571 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
5572 Priv_Id
: Entity_Id
:= Empty
;
5575 if Ekind
(P
) = E_Package
5576 and then not In_Open_Scopes
(P
)
5578 Priv_Id
:= First_Private_Entity
(P
);
5581 if P
= Standard_Standard
then
5582 Change_Selected_Component_To_Expanded_Name
(N
);
5583 Rewrite
(N
, Selector_Name
(N
));
5585 Set_Etype
(Original_Node
(N
), Standard_Character
);
5589 Id
:= First_Entity
(P
);
5591 and then Id
/= Priv_Id
5593 if Is_Standard_Character_Type
(Id
)
5594 and then Id
= Base_Type
(Id
)
5596 -- We replace the node with the literal itself, resolve as a
5597 -- character, and set the type correctly.
5600 Change_Selected_Component_To_Expanded_Name
(N
);
5601 Rewrite
(N
, Selector_Name
(N
));
5604 Set_Etype
(Original_Node
(N
), Id
);
5608 -- More than one type derived from Character in given scope.
5609 -- Collect all possible interpretations.
5611 Add_One_Interp
(N
, Id
, Id
);
5619 end Has_Implicit_Character_Literal
;
5621 ----------------------
5622 -- Has_Private_With --
5623 ----------------------
5625 function Has_Private_With
(E
: Entity_Id
) return Boolean is
5626 Comp_Unit
: constant Node_Id
:= Cunit
(Current_Sem_Unit
);
5630 Item
:= First
(Context_Items
(Comp_Unit
));
5631 while Present
(Item
) loop
5632 if Nkind
(Item
) = N_With_Clause
5633 and then Private_Present
(Item
)
5634 and then Entity
(Name
(Item
)) = E
5643 end Has_Private_With
;
5645 ---------------------------
5646 -- Has_Implicit_Operator --
5647 ---------------------------
5649 function Has_Implicit_Operator
(N
: Node_Id
) return Boolean is
5650 Op_Id
: constant Name_Id
:= Chars
(Selector_Name
(N
));
5651 P
: constant Entity_Id
:= Entity
(Prefix
(N
));
5653 Priv_Id
: Entity_Id
:= Empty
;
5655 procedure Add_Implicit_Operator
5657 Op_Type
: Entity_Id
:= Empty
);
5658 -- Add implicit interpretation to node N, using the type for which a
5659 -- predefined operator exists. If the operator yields a boolean type,
5660 -- the Operand_Type is implicitly referenced by the operator, and a
5661 -- reference to it must be generated.
5663 ---------------------------
5664 -- Add_Implicit_Operator --
5665 ---------------------------
5667 procedure Add_Implicit_Operator
5669 Op_Type
: Entity_Id
:= Empty
)
5671 Predef_Op
: Entity_Id
;
5674 Predef_Op
:= Current_Entity
(Selector_Name
(N
));
5676 while Present
(Predef_Op
)
5677 and then Scope
(Predef_Op
) /= Standard_Standard
5679 Predef_Op
:= Homonym
(Predef_Op
);
5682 if Nkind
(N
) = N_Selected_Component
then
5683 Change_Selected_Component_To_Expanded_Name
(N
);
5686 Add_One_Interp
(N
, Predef_Op
, T
);
5688 -- For operators with unary and binary interpretations, add both
5690 if Present
(Homonym
(Predef_Op
)) then
5691 Add_One_Interp
(N
, Homonym
(Predef_Op
), T
);
5694 -- The node is a reference to a predefined operator, and
5695 -- an implicit reference to the type of its operands.
5697 if Present
(Op_Type
) then
5698 Generate_Operator_Reference
(N
, Op_Type
);
5700 Generate_Operator_Reference
(N
, T
);
5702 end Add_Implicit_Operator
;
5704 -- Start of processing for Has_Implicit_Operator
5707 if Ekind
(P
) = E_Package
5708 and then not In_Open_Scopes
(P
)
5710 Priv_Id
:= First_Private_Entity
(P
);
5713 Id
:= First_Entity
(P
);
5717 -- Boolean operators: an implicit declaration exists if the scope
5718 -- contains a declaration for a derived Boolean type, or for an
5719 -- array of Boolean type.
5721 when Name_Op_And | Name_Op_Not | Name_Op_Or | Name_Op_Xor
=>
5722 while Id
/= Priv_Id
loop
5723 if Valid_Boolean_Arg
(Id
)
5724 and then Id
= Base_Type
(Id
)
5726 Add_Implicit_Operator
(Id
);
5733 -- Equality: look for any non-limited type (result is Boolean)
5735 when Name_Op_Eq | Name_Op_Ne
=>
5736 while Id
/= Priv_Id
loop
5738 and then not Is_Limited_Type
(Id
)
5739 and then Id
= Base_Type
(Id
)
5741 Add_Implicit_Operator
(Standard_Boolean
, Id
);
5748 -- Comparison operators: scalar type, or array of scalar
5750 when Name_Op_Lt | Name_Op_Le | Name_Op_Gt | Name_Op_Ge
=>
5751 while Id
/= Priv_Id
loop
5752 if (Is_Scalar_Type
(Id
)
5753 or else (Is_Array_Type
(Id
)
5754 and then Is_Scalar_Type
(Component_Type
(Id
))))
5755 and then Id
= Base_Type
(Id
)
5757 Add_Implicit_Operator
(Standard_Boolean
, Id
);
5764 -- Arithmetic operators: any numeric type
5774 while Id
/= Priv_Id
loop
5775 if Is_Numeric_Type
(Id
)
5776 and then Id
= Base_Type
(Id
)
5778 Add_Implicit_Operator
(Id
);
5785 -- Concatenation: any one-dimensional array type
5787 when Name_Op_Concat
=>
5788 while Id
/= Priv_Id
loop
5789 if Is_Array_Type
(Id
) and then Number_Dimensions
(Id
) = 1
5790 and then Id
= Base_Type
(Id
)
5792 Add_Implicit_Operator
(Id
);
5799 -- What is the others condition here? Should we be using a
5800 -- subtype of Name_Id that would restrict to operators ???
5802 when others => null;
5805 -- If we fall through, then we do not have an implicit operator
5809 end Has_Implicit_Operator
;
5811 --------------------
5812 -- In_Open_Scopes --
5813 --------------------
5815 function In_Open_Scopes
(S
: Entity_Id
) return Boolean is
5817 -- Several scope stacks are maintained by Scope_Stack. The base of the
5818 -- currently active scope stack is denoted by the Is_Active_Stack_Base
5819 -- flag in the scope stack entry. Note that the scope stacks used to
5820 -- simply be delimited implicitly by the presence of Standard_Standard
5821 -- at their base, but there now are cases where this is not sufficient
5822 -- because Standard_Standard actually may appear in the middle of the
5823 -- active set of scopes.
5825 for J
in reverse 0 .. Scope_Stack
.Last
loop
5826 if Scope_Stack
.Table
(J
).Entity
= S
then
5830 -- Check Is_Active_Stack_Base to tell us when to stop, as there are
5831 -- cases where Standard_Standard appears in the middle of the active
5832 -- set of scopes. This affects the declaration and overriding of
5833 -- private inherited operations in instantiations of generic child
5836 exit when Scope_Stack
.Table
(J
).Is_Active_Stack_Base
;
5842 -----------------------------
5843 -- Inherit_Renamed_Profile --
5844 -----------------------------
5846 procedure Inherit_Renamed_Profile
(New_S
: Entity_Id
; Old_S
: Entity_Id
) is
5853 if Ekind
(Old_S
) = E_Operator
then
5854 New_F
:= First_Formal
(New_S
);
5856 while Present
(New_F
) loop
5857 Set_Etype
(New_F
, Base_Type
(Etype
(New_F
)));
5858 Next_Formal
(New_F
);
5861 Set_Etype
(New_S
, Base_Type
(Etype
(New_S
)));
5864 New_F
:= First_Formal
(New_S
);
5865 Old_F
:= First_Formal
(Old_S
);
5867 while Present
(New_F
) loop
5868 New_T
:= Etype
(New_F
);
5869 Old_T
:= Etype
(Old_F
);
5871 -- If the new type is a renaming of the old one, as is the
5872 -- case for actuals in instances, retain its name, to simplify
5873 -- later disambiguation.
5875 if Nkind
(Parent
(New_T
)) = N_Subtype_Declaration
5876 and then Is_Entity_Name
(Subtype_Indication
(Parent
(New_T
)))
5877 and then Entity
(Subtype_Indication
(Parent
(New_T
))) = Old_T
5881 Set_Etype
(New_F
, Old_T
);
5884 Next_Formal
(New_F
);
5885 Next_Formal
(Old_F
);
5888 if Ekind
(Old_S
) = E_Function
5889 or else Ekind
(Old_S
) = E_Enumeration_Literal
5891 Set_Etype
(New_S
, Etype
(Old_S
));
5894 end Inherit_Renamed_Profile
;
5900 procedure Initialize
is
5905 -------------------------
5906 -- Install_Use_Clauses --
5907 -------------------------
5909 procedure Install_Use_Clauses
5911 Force_Installation
: Boolean := False)
5919 while Present
(U
) loop
5921 -- Case of USE package
5923 if Nkind
(U
) = N_Use_Package_Clause
then
5924 P
:= First
(Names
(U
));
5925 while Present
(P
) loop
5928 if Ekind
(Id
) = E_Package
then
5930 Note_Redundant_Use
(P
);
5932 elsif Present
(Renamed_Object
(Id
))
5933 and then In_Use
(Renamed_Object
(Id
))
5935 Note_Redundant_Use
(P
);
5937 elsif Force_Installation
or else Applicable_Use
(P
) then
5938 Use_One_Package
(Id
, U
);
5949 P
:= First
(Subtype_Marks
(U
));
5950 while Present
(P
) loop
5951 if not Is_Entity_Name
(P
)
5952 or else No
(Entity
(P
))
5956 elsif Entity
(P
) /= Any_Type
then
5964 Next_Use_Clause
(U
);
5966 end Install_Use_Clauses
;
5968 -------------------------------------
5969 -- Is_Appropriate_For_Entry_Prefix --
5970 -------------------------------------
5972 function Is_Appropriate_For_Entry_Prefix
(T
: Entity_Id
) return Boolean is
5973 P_Type
: Entity_Id
:= T
;
5976 if Is_Access_Type
(P_Type
) then
5977 P_Type
:= Designated_Type
(P_Type
);
5980 return Is_Task_Type
(P_Type
) or else Is_Protected_Type
(P_Type
);
5981 end Is_Appropriate_For_Entry_Prefix
;
5983 -------------------------------
5984 -- Is_Appropriate_For_Record --
5985 -------------------------------
5987 function Is_Appropriate_For_Record
(T
: Entity_Id
) return Boolean is
5989 function Has_Components
(T1
: Entity_Id
) return Boolean;
5990 -- Determine if given type has components (i.e. is either a record
5991 -- type or a type that has discriminants).
5993 --------------------
5994 -- Has_Components --
5995 --------------------
5997 function Has_Components
(T1
: Entity_Id
) return Boolean is
5999 return Is_Record_Type
(T1
)
6000 or else (Is_Private_Type
(T1
) and then Has_Discriminants
(T1
))
6001 or else (Is_Task_Type
(T1
) and then Has_Discriminants
(T1
))
6002 or else (Is_Incomplete_Type
(T1
)
6003 and then From_With_Type
(T1
)
6004 and then Present
(Non_Limited_View
(T1
))
6005 and then Is_Record_Type
6006 (Get_Full_View
(Non_Limited_View
(T1
))));
6009 -- Start of processing for Is_Appropriate_For_Record
6014 and then (Has_Components
(T
)
6015 or else (Is_Access_Type
(T
)
6016 and then Has_Components
(Designated_Type
(T
))));
6017 end Is_Appropriate_For_Record
;
6019 ------------------------
6020 -- Note_Redundant_Use --
6021 ------------------------
6023 procedure Note_Redundant_Use
(Clause
: Node_Id
) is
6024 Pack_Name
: constant Entity_Id
:= Entity
(Clause
);
6025 Cur_Use
: constant Node_Id
:= Current_Use_Clause
(Pack_Name
);
6026 Decl
: constant Node_Id
:= Parent
(Clause
);
6028 Prev_Use
: Node_Id
:= Empty
;
6029 Redundant
: Node_Id
:= Empty
;
6030 -- The Use_Clause which is actually redundant. In the simplest case
6031 -- it is Pack itself, but when we compile a body we install its
6032 -- context before that of its spec, in which case it is the use_clause
6033 -- in the spec that will appear to be redundant, and we want the
6034 -- warning to be placed on the body. Similar complications appear when
6035 -- the redundancy is between a child unit and one of its ancestors.
6038 Set_Redundant_Use
(Clause
, True);
6040 if not Comes_From_Source
(Clause
)
6042 or else not Warn_On_Redundant_Constructs
6047 if not Is_Compilation_Unit
(Current_Scope
) then
6049 -- If the use_clause is in an inner scope, it is made redundant
6050 -- by some clause in the current context, with one exception:
6051 -- If we're compiling a nested package body, and the use_clause
6052 -- comes from the corresponding spec, the clause is not necessarily
6053 -- fully redundant, so we should not warn. If a warning was
6054 -- warranted, it would have been given when the spec was processed.
6056 if Nkind
(Parent
(Decl
)) = N_Package_Specification
then
6058 Package_Spec_Entity
: constant Entity_Id
:=
6059 Defining_Unit_Name
(Parent
(Decl
));
6061 if In_Package_Body
(Package_Spec_Entity
) then
6067 Redundant
:= Clause
;
6068 Prev_Use
:= Cur_Use
;
6070 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
6072 Cur_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Cur_Use
);
6073 New_Unit
: constant Unit_Number_Type
:= Get_Source_Unit
(Clause
);
6077 if Cur_Unit
= New_Unit
then
6079 -- Redundant clause in same body
6081 Redundant
:= Clause
;
6082 Prev_Use
:= Cur_Use
;
6084 elsif Cur_Unit
= Current_Sem_Unit
then
6086 -- If the new clause is not in the current unit it has been
6087 -- analyzed first, and it makes the other one redundant.
6088 -- However, if the new clause appears in a subunit, Cur_Unit
6089 -- is still the parent, and in that case the redundant one
6090 -- is the one appearing in the subunit.
6092 if Nkind
(Unit
(Cunit
(New_Unit
))) = N_Subunit
then
6093 Redundant
:= Clause
;
6094 Prev_Use
:= Cur_Use
;
6096 -- Most common case: redundant clause in body,
6097 -- original clause in spec. Current scope is spec entity.
6102 Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
))))
6104 Redundant
:= Cur_Use
;
6108 -- The new clause may appear in an unrelated unit, when
6109 -- the parents of a generic are being installed prior to
6110 -- instantiation. In this case there must be no warning.
6111 -- We detect this case by checking whether the current top
6112 -- of the stack is related to the current compilation.
6114 Scop
:= Current_Scope
;
6115 while Present
(Scop
)
6116 and then Scop
/= Standard_Standard
6118 if Is_Compilation_Unit
(Scop
)
6119 and then not Is_Child_Unit
(Scop
)
6123 elsif Scop
= Cunit_Entity
(Current_Sem_Unit
) then
6127 Scop
:= Scope
(Scop
);
6130 Redundant
:= Cur_Use
;
6134 elsif New_Unit
= Current_Sem_Unit
then
6135 Redundant
:= Clause
;
6136 Prev_Use
:= Cur_Use
;
6139 -- Neither is the current unit, so they appear in parent or
6140 -- sibling units. Warning will be emitted elsewhere.
6146 elsif Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Declaration
6147 and then Present
(Parent_Spec
(Unit
(Cunit
(Current_Sem_Unit
))))
6149 -- Use_clause is in child unit of current unit, and the child
6150 -- unit appears in the context of the body of the parent, so it
6151 -- has been installed first, even though it is the redundant one.
6152 -- Depending on their placement in the context, the visible or the
6153 -- private parts of the two units, either might appear as redundant,
6154 -- but the message has to be on the current unit.
6156 if Get_Source_Unit
(Cur_Use
) = Current_Sem_Unit
then
6157 Redundant
:= Cur_Use
;
6160 Redundant
:= Clause
;
6161 Prev_Use
:= Cur_Use
;
6164 -- If the new use clause appears in the private part of a parent unit
6165 -- it may appear to be redundant w.r.t. a use clause in a child unit,
6166 -- but the previous use clause was needed in the visible part of the
6167 -- child, and no warning should be emitted.
6169 if Nkind
(Parent
(Decl
)) = N_Package_Specification
6171 List_Containing
(Decl
) = Private_Declarations
(Parent
(Decl
))
6174 Par
: constant Entity_Id
:= Defining_Entity
(Parent
(Decl
));
6175 Spec
: constant Node_Id
:=
6176 Specification
(Unit
(Cunit
(Current_Sem_Unit
)));
6179 if Is_Compilation_Unit
(Par
)
6180 and then Par
/= Cunit_Entity
(Current_Sem_Unit
)
6181 and then Parent
(Cur_Use
) = Spec
6183 List_Containing
(Cur_Use
) = Visible_Declarations
(Spec
)
6190 -- Finally, if the current use clause is in the context then
6191 -- the clause is redundant when it is nested within the unit.
6193 elsif Nkind
(Parent
(Cur_Use
)) = N_Compilation_Unit
6194 and then Nkind
(Parent
(Parent
(Clause
))) /= N_Compilation_Unit
6195 and then Get_Source_Unit
(Cur_Use
) = Get_Source_Unit
(Clause
)
6197 Redundant
:= Clause
;
6198 Prev_Use
:= Cur_Use
;
6204 if Present
(Redundant
) then
6205 Error_Msg_Sloc
:= Sloc
(Prev_Use
);
6207 ("& is already use-visible through previous use clause #?",
6208 Redundant
, Pack_Name
);
6210 end Note_Redundant_Use
;
6216 procedure Pop_Scope
is
6217 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
6220 if Debug_Flag_E
then
6224 Scope_Suppress
:= SST
.Save_Scope_Suppress
;
6225 Local_Suppress_Stack_Top
:= SST
.Save_Local_Suppress_Stack_Top
;
6226 Check_Policy_List
:= SST
.Save_Check_Policy_List
;
6228 if Debug_Flag_W
then
6229 Write_Str
("--> exiting scope: ");
6230 Write_Name
(Chars
(Current_Scope
));
6231 Write_Str
(", Depth=");
6232 Write_Int
(Int
(Scope_Stack
.Last
));
6236 End_Use_Clauses
(SST
.First_Use_Clause
);
6238 -- If the actions to be wrapped are still there they will get lost
6239 -- causing incomplete code to be generated. It is better to abort in
6240 -- this case (and we do the abort even with assertions off since the
6241 -- penalty is incorrect code generation)
6243 if SST
.Actions_To_Be_Wrapped_Before
/= No_List
6245 SST
.Actions_To_Be_Wrapped_After
/= No_List
6250 -- Free last subprogram name if allocated, and pop scope
6252 Free
(SST
.Last_Subprogram_Name
);
6253 Scope_Stack
.Decrement_Last
;
6260 procedure Push_Scope
(S
: Entity_Id
) is
6264 if Ekind
(S
) = E_Void
then
6267 -- Set scope depth if not a non-concurrent type, and we have not
6268 -- yet set the scope depth. This means that we have the first
6269 -- occurrence of the scope, and this is where the depth is set.
6271 elsif (not Is_Type
(S
) or else Is_Concurrent_Type
(S
))
6272 and then not Scope_Depth_Set
(S
)
6274 if S
= Standard_Standard
then
6275 Set_Scope_Depth_Value
(S
, Uint_0
);
6277 elsif Is_Child_Unit
(S
) then
6278 Set_Scope_Depth_Value
(S
, Uint_1
);
6280 elsif not Is_Record_Type
(Current_Scope
) then
6281 if Ekind
(S
) = E_Loop
then
6282 Set_Scope_Depth_Value
(S
, Scope_Depth
(Current_Scope
));
6284 Set_Scope_Depth_Value
(S
, Scope_Depth
(Current_Scope
) + 1);
6289 Scope_Stack
.Increment_Last
;
6292 SST
: Scope_Stack_Entry
renames Scope_Stack
.Table
(Scope_Stack
.Last
);
6296 SST
.Save_Scope_Suppress
:= Scope_Suppress
;
6297 SST
.Save_Local_Suppress_Stack_Top
:= Local_Suppress_Stack_Top
;
6298 SST
.Save_Check_Policy_List
:= Check_Policy_List
;
6300 if Scope_Stack
.Last
> Scope_Stack
.First
then
6301 SST
.Component_Alignment_Default
:= Scope_Stack
.Table
6302 (Scope_Stack
.Last
- 1).
6303 Component_Alignment_Default
;
6306 SST
.Last_Subprogram_Name
:= null;
6307 SST
.Is_Transient
:= False;
6308 SST
.Node_To_Be_Wrapped
:= Empty
;
6309 SST
.Pending_Freeze_Actions
:= No_List
;
6310 SST
.Actions_To_Be_Wrapped_Before
:= No_List
;
6311 SST
.Actions_To_Be_Wrapped_After
:= No_List
;
6312 SST
.First_Use_Clause
:= Empty
;
6313 SST
.Is_Active_Stack_Base
:= False;
6314 SST
.Previous_Visibility
:= False;
6317 if Debug_Flag_W
then
6318 Write_Str
("--> new scope: ");
6319 Write_Name
(Chars
(Current_Scope
));
6320 Write_Str
(", Id=");
6321 Write_Int
(Int
(Current_Scope
));
6322 Write_Str
(", Depth=");
6323 Write_Int
(Int
(Scope_Stack
.Last
));
6327 -- Deal with copying flags from the previous scope to this one. This
6328 -- is not necessary if either scope is standard, or if the new scope
6331 if S
/= Standard_Standard
6332 and then Scope
(S
) /= Standard_Standard
6333 and then not Is_Child_Unit
(S
)
6337 if Nkind
(E
) not in N_Entity
then
6341 -- Copy categorization flags from Scope (S) to S, this is not done
6342 -- when Scope (S) is Standard_Standard since propagation is from
6343 -- library unit entity inwards. Copy other relevant attributes as
6344 -- well (Discard_Names in particular).
6346 -- We only propagate inwards for library level entities,
6347 -- inner level subprograms do not inherit the categorization.
6349 if Is_Library_Level_Entity
(S
) then
6350 Set_Is_Preelaborated
(S
, Is_Preelaborated
(E
));
6351 Set_Is_Shared_Passive
(S
, Is_Shared_Passive
(E
));
6352 Set_Discard_Names
(S
, Discard_Names
(E
));
6353 Set_Suppress_Value_Tracking_On_Call
6354 (S
, Suppress_Value_Tracking_On_Call
(E
));
6355 Set_Categorization_From_Scope
(E
=> S
, Scop
=> E
);
6360 ---------------------
6361 -- Premature_Usage --
6362 ---------------------
6364 procedure Premature_Usage
(N
: Node_Id
) is
6365 Kind
: constant Node_Kind
:= Nkind
(Parent
(Entity
(N
)));
6366 E
: Entity_Id
:= Entity
(N
);
6369 -- Within an instance, the analysis of the actual for a formal object
6370 -- does not see the name of the object itself. This is significant only
6371 -- if the object is an aggregate, where its analysis does not do any
6372 -- name resolution on component associations. (see 4717-008). In such a
6373 -- case, look for the visible homonym on the chain.
6376 and then Present
(Homonym
(E
))
6381 and then not In_Open_Scopes
(Scope
(E
))
6388 Set_Etype
(N
, Etype
(E
));
6393 if Kind
= N_Component_Declaration
then
6395 ("component&! cannot be used before end of record declaration", N
);
6397 elsif Kind
= N_Parameter_Specification
then
6399 ("formal parameter&! cannot be used before end of specification",
6402 elsif Kind
= N_Discriminant_Specification
then
6404 ("discriminant&! cannot be used before end of discriminant part",
6407 elsif Kind
= N_Procedure_Specification
6408 or else Kind
= N_Function_Specification
6411 ("subprogram&! cannot be used before end of its declaration",
6414 elsif Kind
= N_Full_Type_Declaration
then
6416 ("type& cannot be used before end of its declaration!", N
);
6420 ("object& cannot be used before end of its declaration!", N
);
6422 end Premature_Usage
;
6424 ------------------------
6425 -- Present_System_Aux --
6426 ------------------------
6428 function Present_System_Aux
(N
: Node_Id
:= Empty
) return Boolean is
6430 Aux_Name
: Unit_Name_Type
;
6431 Unum
: Unit_Number_Type
;
6436 function Find_System
(C_Unit
: Node_Id
) return Entity_Id
;
6437 -- Scan context clause of compilation unit to find with_clause
6444 function Find_System
(C_Unit
: Node_Id
) return Entity_Id
is
6445 With_Clause
: Node_Id
;
6448 With_Clause
:= First
(Context_Items
(C_Unit
));
6449 while Present
(With_Clause
) loop
6450 if (Nkind
(With_Clause
) = N_With_Clause
6451 and then Chars
(Name
(With_Clause
)) = Name_System
)
6452 and then Comes_From_Source
(With_Clause
)
6463 -- Start of processing for Present_System_Aux
6466 -- The child unit may have been loaded and analyzed already
6468 if Present
(System_Aux_Id
) then
6471 -- If no previous pragma for System.Aux, nothing to load
6473 elsif No
(System_Extend_Unit
) then
6476 -- Use the unit name given in the pragma to retrieve the unit.
6477 -- Verify that System itself appears in the context clause of the
6478 -- current compilation. If System is not present, an error will
6479 -- have been reported already.
6482 With_Sys
:= Find_System
(Cunit
(Current_Sem_Unit
));
6484 The_Unit
:= Unit
(Cunit
(Current_Sem_Unit
));
6488 (Nkind
(The_Unit
) = N_Package_Body
6489 or else (Nkind
(The_Unit
) = N_Subprogram_Body
6491 not Acts_As_Spec
(Cunit
(Current_Sem_Unit
))))
6493 With_Sys
:= Find_System
(Library_Unit
(Cunit
(Current_Sem_Unit
)));
6497 and then Present
(N
)
6499 -- If we are compiling a subunit, we need to examine its
6500 -- context as well (Current_Sem_Unit is the parent unit);
6502 The_Unit
:= Parent
(N
);
6503 while Nkind
(The_Unit
) /= N_Compilation_Unit
loop
6504 The_Unit
:= Parent
(The_Unit
);
6507 if Nkind
(Unit
(The_Unit
)) = N_Subunit
then
6508 With_Sys
:= Find_System
(The_Unit
);
6512 if No
(With_Sys
) then
6516 Loc
:= Sloc
(With_Sys
);
6517 Get_Name_String
(Chars
(Expression
(System_Extend_Unit
)));
6518 Name_Buffer
(8 .. Name_Len
+ 7) := Name_Buffer
(1 .. Name_Len
);
6519 Name_Buffer
(1 .. 7) := "system.";
6520 Name_Buffer
(Name_Len
+ 8) := '%';
6521 Name_Buffer
(Name_Len
+ 9) := 's';
6522 Name_Len
:= Name_Len
+ 9;
6523 Aux_Name
:= Name_Find
;
6527 (Load_Name
=> Aux_Name
,
6530 Error_Node
=> With_Sys
);
6532 if Unum
/= No_Unit
then
6533 Semantics
(Cunit
(Unum
));
6535 Defining_Entity
(Specification
(Unit
(Cunit
(Unum
))));
6538 Make_With_Clause
(Loc
,
6540 Make_Expanded_Name
(Loc
,
6541 Chars
=> Chars
(System_Aux_Id
),
6542 Prefix
=> New_Reference_To
(Scope
(System_Aux_Id
), Loc
),
6543 Selector_Name
=> New_Reference_To
(System_Aux_Id
, Loc
)));
6545 Set_Entity
(Name
(Withn
), System_Aux_Id
);
6547 Set_Library_Unit
(Withn
, Cunit
(Unum
));
6548 Set_Corresponding_Spec
(Withn
, System_Aux_Id
);
6549 Set_First_Name
(Withn
, True);
6550 Set_Implicit_With
(Withn
, True);
6552 Insert_After
(With_Sys
, Withn
);
6553 Mark_Rewrite_Insertion
(Withn
);
6554 Set_Context_Installed
(Withn
);
6558 -- Here if unit load failed
6561 Error_Msg_Name_1
:= Name_System
;
6562 Error_Msg_Name_2
:= Chars
(Expression
(System_Extend_Unit
));
6564 ("extension package `%.%` does not exist",
6565 Opt
.System_Extend_Unit
);
6569 end Present_System_Aux
;
6571 -------------------------
6572 -- Restore_Scope_Stack --
6573 -------------------------
6575 procedure Restore_Scope_Stack
(Handle_Use
: Boolean := True) is
6578 Comp_Unit
: Node_Id
;
6579 In_Child
: Boolean := False;
6580 Full_Vis
: Boolean := True;
6581 SS_Last
: constant Int
:= Scope_Stack
.Last
;
6584 -- Restore visibility of previous scope stack, if any
6586 for J
in reverse 0 .. Scope_Stack
.Last
loop
6587 exit when Scope_Stack
.Table
(J
).Entity
= Standard_Standard
6588 or else No
(Scope_Stack
.Table
(J
).Entity
);
6590 S
:= Scope_Stack
.Table
(J
).Entity
;
6592 if not Is_Hidden_Open_Scope
(S
) then
6594 -- If the parent scope is hidden, its entities are hidden as
6595 -- well, unless the entity is the instantiation currently
6598 if not Is_Hidden_Open_Scope
(Scope
(S
))
6599 or else not Analyzed
(Parent
(S
))
6600 or else Scope
(S
) = Standard_Standard
6602 Set_Is_Immediately_Visible
(S
, True);
6605 E
:= First_Entity
(S
);
6606 while Present
(E
) loop
6607 if Is_Child_Unit
(E
) then
6608 Set_Is_Immediately_Visible
(E
,
6609 Is_Visible_Child_Unit
(E
) or else In_Open_Scopes
(E
));
6611 Set_Is_Immediately_Visible
(E
, True);
6616 if not Full_Vis
then
6617 exit when E
= First_Private_Entity
(S
);
6621 -- The visibility of child units (siblings of current compilation)
6622 -- must be restored in any case. Their declarations may appear
6623 -- after the private part of the parent.
6625 if not Full_Vis
then
6626 while Present
(E
) loop
6627 if Is_Child_Unit
(E
) then
6628 Set_Is_Immediately_Visible
(E
,
6629 Is_Visible_Child_Unit
(E
) or else In_Open_Scopes
(E
));
6637 if Is_Child_Unit
(S
)
6638 and not In_Child
-- check only for current unit
6642 -- Restore visibility of parents according to whether the child
6643 -- is private and whether we are in its visible part.
6645 Comp_Unit
:= Parent
(Unit_Declaration_Node
(S
));
6647 if Nkind
(Comp_Unit
) = N_Compilation_Unit
6648 and then Private_Present
(Comp_Unit
)
6652 elsif Is_Package_Or_Generic_Package
(S
)
6653 and then (In_Private_Part
(S
)
6654 or else In_Package_Body
(S
))
6658 -- if S is the scope of some instance (which has already been
6659 -- seen on the stack) it does not affect the visibility of
6662 elsif Is_Hidden_Open_Scope
(S
) then
6665 elsif (Ekind
(S
) = E_Procedure
6666 or else Ekind
(S
) = E_Function
)
6667 and then Has_Completion
(S
)
6678 if SS_Last
>= Scope_Stack
.First
6679 and then Scope_Stack
.Table
(SS_Last
).Entity
/= Standard_Standard
6682 Install_Use_Clauses
(Scope_Stack
.Table
(SS_Last
).First_Use_Clause
);
6684 end Restore_Scope_Stack
;
6686 ----------------------
6687 -- Save_Scope_Stack --
6688 ----------------------
6690 procedure Save_Scope_Stack
(Handle_Use
: Boolean := True) is
6693 SS_Last
: constant Int
:= Scope_Stack
.Last
;
6696 if SS_Last
>= Scope_Stack
.First
6697 and then Scope_Stack
.Table
(SS_Last
).Entity
/= Standard_Standard
6700 End_Use_Clauses
(Scope_Stack
.Table
(SS_Last
).First_Use_Clause
);
6703 -- If the call is from within a compilation unit, as when called from
6704 -- Rtsfind, make current entries in scope stack invisible while we
6705 -- analyze the new unit.
6707 for J
in reverse 0 .. SS_Last
loop
6708 exit when Scope_Stack
.Table
(J
).Entity
= Standard_Standard
6709 or else No
(Scope_Stack
.Table
(J
).Entity
);
6711 S
:= Scope_Stack
.Table
(J
).Entity
;
6712 Set_Is_Immediately_Visible
(S
, False);
6714 E
:= First_Entity
(S
);
6715 while Present
(E
) loop
6716 Set_Is_Immediately_Visible
(E
, False);
6722 end Save_Scope_Stack
;
6728 procedure Set_Use
(L
: List_Id
) is
6730 Pack_Name
: Node_Id
;
6737 while Present
(Decl
) loop
6738 if Nkind
(Decl
) = N_Use_Package_Clause
then
6739 Chain_Use_Clause
(Decl
);
6741 Pack_Name
:= First
(Names
(Decl
));
6742 while Present
(Pack_Name
) loop
6743 Pack
:= Entity
(Pack_Name
);
6745 if Ekind
(Pack
) = E_Package
6746 and then Applicable_Use
(Pack_Name
)
6748 Use_One_Package
(Pack
, Decl
);
6754 elsif Nkind
(Decl
) = N_Use_Type_Clause
then
6755 Chain_Use_Clause
(Decl
);
6757 Id
:= First
(Subtype_Marks
(Decl
));
6758 while Present
(Id
) loop
6759 if Entity
(Id
) /= Any_Type
then
6772 ---------------------
6773 -- Use_One_Package --
6774 ---------------------
6776 procedure Use_One_Package
(P
: Entity_Id
; N
: Node_Id
) is
6779 Current_Instance
: Entity_Id
:= Empty
;
6781 Private_With_OK
: Boolean := False;
6784 if Ekind
(P
) /= E_Package
then
6789 Set_Current_Use_Clause
(P
, N
);
6791 -- Ada 2005 (AI-50217): Check restriction
6793 if From_With_Type
(P
) then
6794 Error_Msg_N
("limited withed package cannot appear in use clause", N
);
6797 -- Find enclosing instance, if any
6800 Current_Instance
:= Current_Scope
;
6801 while not Is_Generic_Instance
(Current_Instance
) loop
6802 Current_Instance
:= Scope
(Current_Instance
);
6805 if No
(Hidden_By_Use_Clause
(N
)) then
6806 Set_Hidden_By_Use_Clause
(N
, New_Elmt_List
);
6810 -- If unit is a package renaming, indicate that the renamed
6811 -- package is also in use (the flags on both entities must
6812 -- remain consistent, and a subsequent use of either of them
6813 -- should be recognized as redundant).
6815 if Present
(Renamed_Object
(P
)) then
6816 Set_In_Use
(Renamed_Object
(P
));
6817 Set_Current_Use_Clause
(Renamed_Object
(P
), N
);
6818 Real_P
:= Renamed_Object
(P
);
6823 -- Ada 2005 (AI-262): Check the use_clause of a private withed package
6824 -- found in the private part of a package specification
6826 if In_Private_Part
(Current_Scope
)
6827 and then Has_Private_With
(P
)
6828 and then Is_Child_Unit
(Current_Scope
)
6829 and then Is_Child_Unit
(P
)
6830 and then Is_Ancestor_Package
(Scope
(Current_Scope
), P
)
6832 Private_With_OK
:= True;
6835 -- Loop through entities in one package making them potentially
6838 Id
:= First_Entity
(P
);
6840 and then (Id
/= First_Private_Entity
(P
)
6841 or else Private_With_OK
) -- Ada 2005 (AI-262)
6843 Prev
:= Current_Entity
(Id
);
6844 while Present
(Prev
) loop
6845 if Is_Immediately_Visible
(Prev
)
6846 and then (not Is_Overloadable
(Prev
)
6847 or else not Is_Overloadable
(Id
)
6848 or else (Type_Conformant
(Id
, Prev
)))
6850 if No
(Current_Instance
) then
6852 -- Potentially use-visible entity remains hidden
6854 goto Next_Usable_Entity
;
6856 -- A use clause within an instance hides outer global entities,
6857 -- which are not used to resolve local entities in the
6858 -- instance. Note that the predefined entities in Standard
6859 -- could not have been hidden in the generic by a use clause,
6860 -- and therefore remain visible. Other compilation units whose
6861 -- entities appear in Standard must be hidden in an instance.
6863 -- To determine whether an entity is external to the instance
6864 -- we compare the scope depth of its scope with that of the
6865 -- current instance. However, a generic actual of a subprogram
6866 -- instance is declared in the wrapper package but will not be
6867 -- hidden by a use-visible entity.
6869 -- If Id is called Standard, the predefined package with the
6870 -- same name is in the homonym chain. It has to be ignored
6871 -- because it has no defined scope (being the only entity in
6872 -- the system with this mandated behavior).
6874 elsif not Is_Hidden
(Id
)
6875 and then Present
(Scope
(Prev
))
6876 and then not Is_Wrapper_Package
(Scope
(Prev
))
6877 and then Scope_Depth
(Scope
(Prev
)) <
6878 Scope_Depth
(Current_Instance
)
6879 and then (Scope
(Prev
) /= Standard_Standard
6880 or else Sloc
(Prev
) > Standard_Location
)
6882 Set_Is_Potentially_Use_Visible
(Id
);
6883 Set_Is_Immediately_Visible
(Prev
, False);
6884 Append_Elmt
(Prev
, Hidden_By_Use_Clause
(N
));
6887 -- A user-defined operator is not use-visible if the predefined
6888 -- operator for the type is immediately visible, which is the case
6889 -- if the type of the operand is in an open scope. This does not
6890 -- apply to user-defined operators that have operands of different
6891 -- types, because the predefined mixed mode operations (multiply
6892 -- and divide) apply to universal types and do not hide anything.
6894 elsif Ekind
(Prev
) = E_Operator
6895 and then Operator_Matches_Spec
(Prev
, Id
)
6896 and then In_Open_Scopes
6897 (Scope
(Base_Type
(Etype
(First_Formal
(Id
)))))
6898 and then (No
(Next_Formal
(First_Formal
(Id
)))
6899 or else Etype
(First_Formal
(Id
))
6900 = Etype
(Next_Formal
(First_Formal
(Id
)))
6901 or else Chars
(Prev
) = Name_Op_Expon
)
6903 goto Next_Usable_Entity
;
6906 Prev
:= Homonym
(Prev
);
6909 -- On exit, we know entity is not hidden, unless it is private
6911 if not Is_Hidden
(Id
)
6912 and then ((not Is_Child_Unit
(Id
))
6913 or else Is_Visible_Child_Unit
(Id
))
6915 Set_Is_Potentially_Use_Visible
(Id
);
6917 if Is_Private_Type
(Id
)
6918 and then Present
(Full_View
(Id
))
6920 Set_Is_Potentially_Use_Visible
(Full_View
(Id
));
6924 <<Next_Usable_Entity
>>
6928 -- Child units are also made use-visible by a use clause, but they may
6929 -- appear after all visible declarations in the parent entity list.
6931 while Present
(Id
) loop
6932 if Is_Child_Unit
(Id
)
6933 and then Is_Visible_Child_Unit
(Id
)
6935 Set_Is_Potentially_Use_Visible
(Id
);
6941 if Chars
(Real_P
) = Name_System
6942 and then Scope
(Real_P
) = Standard_Standard
6943 and then Present_System_Aux
(N
)
6945 Use_One_Package
(System_Aux_Id
, N
);
6948 end Use_One_Package
;
6954 procedure Use_One_Type
(Id
: Node_Id
) is
6956 Is_Known_Used
: Boolean;
6960 function Spec_Reloaded_For_Body
return Boolean;
6961 -- Determine whether the compilation unit is a package body and the use
6962 -- type clause is in the spec of the same package. Even though the spec
6963 -- was analyzed first, its context is reloaded when analysing the body.
6965 ----------------------------
6966 -- Spec_Reloaded_For_Body --
6967 ----------------------------
6969 function Spec_Reloaded_For_Body
return Boolean is
6971 if Nkind
(Unit
(Cunit
(Current_Sem_Unit
))) = N_Package_Body
then
6973 Spec
: constant Node_Id
:=
6974 Parent
(List_Containing
(Parent
(Id
)));
6977 Nkind
(Spec
) = N_Package_Specification
6978 and then Corresponding_Body
(Parent
(Spec
)) =
6979 Cunit_Entity
(Current_Sem_Unit
);
6984 end Spec_Reloaded_For_Body
;
6986 -- Start of processing for Use_One_Type;
6989 -- It is the type determined by the subtype mark (8.4(8)) whose
6990 -- operations become potentially use-visible.
6992 T
:= Base_Type
(Entity
(Id
));
6994 -- Either the type itself is used, the package where it is declared
6995 -- is in use or the entity is declared in the current package, thus
7000 or else In_Use
(Scope
(T
))
7001 or else Scope
(T
) = Current_Scope
;
7003 Set_Redundant_Use
(Id
,
7004 Is_Known_Used
or else Is_Potentially_Use_Visible
(T
));
7006 if In_Open_Scopes
(Scope
(T
)) then
7009 -- A limited view cannot appear in a use_type clause. However, an
7010 -- access type whose designated type is limited has the flag but
7011 -- is not itself a limited view unless we only have a limited view
7012 -- of its enclosing package.
7014 elsif From_With_Type
(T
)
7015 and then From_With_Type
(Scope
(T
))
7018 ("incomplete type from limited view "
7019 & "cannot appear in use clause", Id
);
7021 -- If the subtype mark designates a subtype in a different package,
7022 -- we have to check that the parent type is visible, otherwise the
7023 -- use type clause is a noop. Not clear how to do that???
7025 elsif not Redundant_Use
(Id
) then
7027 Set_Current_Use_Clause
(T
, Parent
(Id
));
7028 Op_List
:= Collect_Primitive_Operations
(T
);
7030 Elmt
:= First_Elmt
(Op_List
);
7031 while Present
(Elmt
) loop
7032 if (Nkind
(Node
(Elmt
)) = N_Defining_Operator_Symbol
7033 or else Chars
(Node
(Elmt
)) in Any_Operator_Name
)
7034 and then not Is_Hidden
(Node
(Elmt
))
7036 Set_Is_Potentially_Use_Visible
(Node
(Elmt
));
7043 -- If warning on redundant constructs, check for unnecessary WITH
7045 if Warn_On_Redundant_Constructs
7046 and then Is_Known_Used
7048 -- with P; with P; use P;
7049 -- package P is package X is package body X is
7050 -- type T ... use P.T;
7052 -- The compilation unit is the body of X. GNAT first compiles the
7053 -- spec of X, then proceeds to the body. At that point P is marked
7054 -- as use visible. The analysis then reinstalls the spec along with
7055 -- its context. The use clause P.T is now recognized as redundant,
7056 -- but in the wrong context. Do not emit a warning in such cases.
7057 -- Do not emit a warning either if we are in an instance, there
7058 -- is no redundancy between an outer use_clause and one that appears
7059 -- within the generic.
7061 and then not Spec_Reloaded_For_Body
7062 and then not In_Instance
7064 -- The type already has a use clause
7068 -- Case where we know the current use clause for the type
7070 if Present
(Current_Use_Clause
(T
)) then
7071 Use_Clause_Known
: declare
7072 Clause1
: constant Node_Id
:= Parent
(Id
);
7073 Clause2
: constant Node_Id
:= Current_Use_Clause
(T
);
7080 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
;
7081 -- Return the appropriate entity for determining which unit
7082 -- has a deeper scope: the defining entity for U, unless U
7083 -- is a package instance, in which case we retrieve the
7084 -- entity of the instance spec.
7086 --------------------
7087 -- Entity_Of_Unit --
7088 --------------------
7090 function Entity_Of_Unit
(U
: Node_Id
) return Entity_Id
is
7092 if Nkind
(U
) = N_Package_Instantiation
7093 and then Analyzed
(U
)
7095 return Defining_Entity
(Instance_Spec
(U
));
7097 return Defining_Entity
(U
);
7101 -- Start of processing for Use_Clause_Known
7104 -- If both current use type clause and the use type
7105 -- clause for the type are at the compilation unit level,
7106 -- one of the units must be an ancestor of the other, and
7107 -- the warning belongs on the descendant.
7109 if Nkind
(Parent
(Clause1
)) = N_Compilation_Unit
7111 Nkind
(Parent
(Clause2
)) = N_Compilation_Unit
7113 Unit1
:= Unit
(Parent
(Clause1
));
7114 Unit2
:= Unit
(Parent
(Clause2
));
7116 -- There is a redundant use type clause in a child unit.
7117 -- Determine which of the units is more deeply nested.
7118 -- If a unit is a package instance, retrieve the entity
7119 -- and its scope from the instance spec.
7121 Ent1
:= Entity_Of_Unit
(Unit1
);
7122 Ent2
:= Entity_Of_Unit
(Unit2
);
7124 if Scope
(Ent2
) = Standard_Standard
then
7125 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7128 elsif Scope
(Ent1
) = Standard_Standard
then
7129 Error_Msg_Sloc
:= Sloc
(Id
);
7132 -- If both units are child units, we determine which one
7133 -- is the descendant by the scope distance to the
7134 -- ultimate parent unit.
7143 while S1
/= Standard_Standard
7145 S2
/= Standard_Standard
7151 if S1
= Standard_Standard
then
7152 Error_Msg_Sloc
:= Sloc
(Id
);
7155 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(T
));
7162 ("& is already use-visible through previous "
7163 & "use_type_clause #?", Err_No
, Id
);
7165 -- Case where current use type clause and the use type
7166 -- clause for the type are not both at the compilation unit
7167 -- level. In this case we don't have location information.
7171 ("& is already use-visible through previous "
7172 & "use type clause?", Id
, Id
);
7174 end Use_Clause_Known
;
7176 -- Here if Current_Use_Clause is not set for T, another case
7177 -- where we do not have the location information available.
7181 ("& is already use-visible through previous "
7182 & "use type clause?", Id
, Id
);
7185 -- The package where T is declared is already used
7187 elsif In_Use
(Scope
(T
)) then
7188 Error_Msg_Sloc
:= Sloc
(Current_Use_Clause
(Scope
(T
)));
7190 ("& is already use-visible through package use clause #?",
7193 -- The current scope is the package where T is declared
7196 Error_Msg_Node_2
:= Scope
(T
);
7198 ("& is already use-visible inside package &?", Id
, Id
);
7207 procedure Write_Info
is
7208 Id
: Entity_Id
:= First_Entity
(Current_Scope
);
7211 -- No point in dumping standard entities
7213 if Current_Scope
= Standard_Standard
then
7217 Write_Str
("========================================================");
7219 Write_Str
(" Defined Entities in ");
7220 Write_Name
(Chars
(Current_Scope
));
7222 Write_Str
("========================================================");
7226 Write_Str
("-- none --");
7230 while Present
(Id
) loop
7231 Write_Entity_Info
(Id
, " ");
7236 if Scope
(Current_Scope
) = Standard_Standard
then
7238 -- Print information on the current unit itself
7240 Write_Entity_Info
(Current_Scope
, " ");
7250 procedure Write_Scopes
is
7253 for J
in reverse 1 .. Scope_Stack
.Last
loop
7254 S
:= Scope_Stack
.Table
(J
).Entity
;
7255 Write_Int
(Int
(S
));
7256 Write_Str
(" === ");
7257 Write_Name
(Chars
(S
));