1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2024, 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 Accessibility
; use Accessibility
;
27 with Aspects
; use Aspects
;
28 with Atree
; use Atree
;
29 with Debug
; use Debug
;
30 with Einfo
; use Einfo
;
31 with Einfo
.Entities
; use Einfo
.Entities
;
32 with Einfo
.Utils
; use Einfo
.Utils
;
33 with Elists
; use Elists
;
34 with Errout
; use Errout
;
35 with Exp_Util
; use Exp_Util
;
36 with Itypes
; use Itypes
;
38 with Lib
.Xref
; use Lib
.Xref
;
39 with Namet
; use Namet
;
40 with Namet
.Sp
; use Namet
.Sp
;
41 with Nlists
; use Nlists
;
42 with Nmake
; use Nmake
;
44 with Output
; use Output
;
45 with Restrict
; use Restrict
;
46 with Rident
; use Rident
;
47 with Rtsfind
; use Rtsfind
;
49 with Sem_Aux
; use Sem_Aux
;
50 with Sem_Case
; use Sem_Case
;
51 with Sem_Cat
; use Sem_Cat
;
52 with Sem_Ch3
; use Sem_Ch3
;
53 with Sem_Ch6
; use Sem_Ch6
;
54 with Sem_Ch8
; use Sem_Ch8
;
55 with Sem_Dim
; use Sem_Dim
;
56 with Sem_Disp
; use Sem_Disp
;
57 with Sem_Dist
; use Sem_Dist
;
58 with Sem_Eval
; use Sem_Eval
;
59 with Sem_Res
; use Sem_Res
;
60 with Sem_Type
; use Sem_Type
;
61 with Sem_Util
; use Sem_Util
;
62 with Sem_Warn
; use Sem_Warn
;
63 with Stand
; use Stand
;
64 with Sinfo
; use Sinfo
;
65 with Sinfo
.Nodes
; use Sinfo
.Nodes
;
66 with Sinfo
.Utils
; use Sinfo
.Utils
;
67 with Snames
; use Snames
;
68 with Style
; use Style
;
69 with Tbuild
; use Tbuild
;
70 with Uintp
; use Uintp
;
71 with Warnsw
; use Warnsw
;
73 package body Sem_Ch4
is
75 -- Tables which speed up the identification of dangerous calls to Ada 2012
76 -- functions with writable actuals (AI05-0144).
78 -- The following table enumerates the Ada constructs which may evaluate in
79 -- arbitrary order. It does not cover all the language constructs which can
80 -- be evaluated in arbitrary order but the subset needed for AI05-0144.
82 Has_Arbitrary_Evaluation_Order
: constant array (Node_Kind
) of Boolean :=
84 N_Assignment_Statement
=> True,
85 N_Entry_Call_Statement
=> True,
86 N_Extension_Aggregate
=> True,
87 N_Full_Type_Declaration
=> True,
88 N_Indexed_Component
=> True,
89 N_Object_Declaration
=> True,
93 N_Array_Type_Definition
=> True,
94 N_Membership_Test
=> True,
96 N_Subprogram_Call
=> True,
99 -- The following table enumerates the nodes on which we stop climbing when
100 -- locating the outermost Ada construct that can be evaluated in arbitrary
103 Stop_Subtree_Climbing
: constant array (Node_Kind
) of Boolean :=
104 (N_Aggregate
=> True,
105 N_Assignment_Statement
=> True,
106 N_Entry_Call_Statement
=> True,
107 N_Extended_Return_Statement
=> True,
108 N_Extension_Aggregate
=> True,
109 N_Full_Type_Declaration
=> True,
110 N_Object_Declaration
=> True,
111 N_Object_Renaming_Declaration
=> True,
112 N_Package_Specification
=> True,
114 N_Procedure_Call_Statement
=> True,
115 N_Simple_Return_Statement
=> True,
116 N_Has_Condition
=> True,
119 -----------------------
120 -- Local Subprograms --
121 -----------------------
123 procedure Analyze_Concatenation_Rest
(N
: Node_Id
);
124 -- Does the "rest" of the work of Analyze_Concatenation, after the left
125 -- operand has been analyzed. See Analyze_Concatenation for details.
127 procedure Analyze_Expression
(N
: Node_Id
);
128 -- For expressions that are not names, this is just a call to analyze. If
129 -- the expression is a name, it may be a call to a parameterless function,
130 -- and if so must be converted into an explicit call node and analyzed as
131 -- such. This deproceduring must be done during the first pass of overload
132 -- resolution, because otherwise a procedure call with overloaded actuals
133 -- may fail to resolve.
135 procedure Analyze_Operator_Call
(N
: Node_Id
; Op_Id
: Entity_Id
);
136 -- Analyze a call of the form "+"(x, y), etc. The prefix of the call is an
137 -- operator name or an expanded name whose selector is an operator name,
138 -- and one possible interpretation is as a predefined operator.
140 procedure Analyze_Overloaded_Selected_Component
(N
: Node_Id
);
141 -- If the prefix of a selected_component is overloaded, the proper
142 -- interpretation that yields a record type with the proper selector
143 -- name must be selected.
145 procedure Analyze_User_Defined_Binary_Op
(N
: Node_Id
; Op_Id
: Entity_Id
);
146 -- Procedure to analyze a user defined binary operator, which is resolved
147 -- like a function, but instead of a list of actuals it is presented
148 -- with the left and right operands of an operator node.
150 procedure Analyze_User_Defined_Unary_Op
(N
: Node_Id
; Op_Id
: Entity_Id
);
151 -- Procedure to analyze a user defined unary operator, which is resolved
152 -- like a function, but instead of a list of actuals, it is presented with
153 -- the operand of the operator node.
155 procedure Analyze_One_Call
159 Success
: out Boolean;
160 Skip_First
: Boolean := False);
161 -- Check one interpretation of an overloaded subprogram name for
162 -- compatibility with the types of the actuals in a call. If there is a
163 -- single interpretation which does not match, post error if Report is
166 -- Nam is the entity that provides the formals against which the actuals
167 -- are checked. Nam is either the name of a subprogram, or the internal
168 -- subprogram type constructed for an access_to_subprogram. If the actuals
169 -- are compatible with Nam, then Nam is added to the list of candidate
170 -- interpretations for N, and Success is set to True.
172 -- The flag Skip_First is used when analyzing a call that was rewritten
173 -- from object notation. In this case the first actual may have to receive
174 -- an explicit dereference, depending on the first formal of the operation
175 -- being called. The caller will have verified that the object is legal
176 -- for the call. If the remaining parameters match, the first parameter
177 -- will rewritten as a dereference if needed, prior to completing analysis.
179 procedure Check_Misspelled_Selector
182 -- Give possible misspelling message if Sel seems likely to be a mis-
183 -- spelling of one of the selectors of the Prefix. This is called by
184 -- Analyze_Selected_Component after producing an invalid selector error
187 procedure Find_Arithmetic_Types
191 -- L and R are the operands of an arithmetic operator. Find consistent
192 -- pairs of interpretations for L and R that have a numeric type consistent
193 -- with the semantics of the operator.
195 procedure Find_Comparison_Equality_Types
199 -- L and R are operands of a comparison or equality operator. Find valid
200 -- pairs of interpretations for L and R.
202 procedure Find_Concatenation_Types
206 -- For the four varieties of concatenation
208 procedure Find_Boolean_Types
212 -- Ditto for binary logical operations
214 procedure Find_Negation_Types
218 -- Find consistent interpretation for operand of negation operator
220 function Find_Primitive_Operation
(N
: Node_Id
) return Boolean;
221 -- Find candidate interpretations for the name Obj.Proc when it appears in
222 -- a subprogram renaming declaration.
224 procedure Find_Unary_Types
228 -- Unary arithmetic types: plus, minus, abs
230 procedure Check_Arithmetic_Pair
234 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid types
235 -- for left and right operand. Determine whether they constitute a valid
236 -- pair for the given operator, and record the corresponding interpretation
237 -- of the operator node. The node N may be an operator node (the usual
238 -- case) or a function call whose prefix is an operator designator. In
239 -- both cases Op_Id is the operator name itself.
241 procedure Diagnose_Call
(N
: Node_Id
; Nam
: Node_Id
);
242 -- Give detailed information on overloaded call where none of the
243 -- interpretations match. N is the call node, Nam the designator for
244 -- the overloaded entity being called.
246 function Junk_Operand
(N
: Node_Id
) return Boolean;
247 -- Test for an operand that is an inappropriate entity (e.g. a package
248 -- name or a label). If so, issue an error message and return True. If
249 -- the operand is not an inappropriate entity kind, return False.
251 procedure Operator_Check
(N
: Node_Id
);
252 -- Verify that an operator has received some valid interpretation. If none
253 -- was found, determine whether a use clause would make the operation
254 -- legal. The variable Candidate_Type (defined in Sem_Type) is set for
255 -- every type compatible with the operator, even if the operator for the
256 -- type is not directly visible. The routine uses this type to emit a more
257 -- informative message.
259 function Has_Possible_User_Defined_Literal
(N
: Node_Id
) return Boolean;
260 -- Ada 2022: if an operand is a literal, it may be subject to an
261 -- implicit conversion to a type for which a user-defined literal
262 -- function exists. During the first pass of type resolution we do
263 -- not know the context imposed on the literal, so we assume that
264 -- the literal type is a valid candidate and rely on the second pass
265 -- of resolution to find the type with the proper aspect. We only
266 -- add this interpretation if no other one was found, which may be
267 -- too restrictive but seems sufficient to handle most proper uses
268 -- of the new aspect. It is unclear whether a full implementation of
269 -- these aspects can be achieved without larger modifications to the
270 -- two-pass resolution algorithm.
272 function Possible_Type_For_Conditional_Expression
273 (T1
, T2
: Entity_Id
) return Entity_Id
;
274 -- Given two types T1 and T2 that are _not_ compatible, return a type that
275 -- may still be used as the possible type of a conditional expression whose
276 -- dependent expressions, or part thereof, have type T1 and T2 respectively
277 -- during the first phase of type resolution, or Empty if such a type does
280 -- The typical example is an if_expression whose then_expression is of a
281 -- tagged type and whose else_expresssion is of an extension of this type:
282 -- the types are not compatible but such an if_expression can be legal if
283 -- its expected type is the 'Class of the tagged type, so the function will
284 -- return the tagged type in this case. If the expected type turns out to
285 -- be something else, including the tagged type itself, then an error will
286 -- be given during the second phase of type resolution.
288 procedure Remove_Abstract_Operations
(N
: Node_Id
);
289 -- Ada 2005: implementation of AI-310. An abstract non-dispatching
290 -- operation is not a candidate interpretation.
292 function Try_Container_Indexing
295 Exprs
: List_Id
) return Boolean;
296 -- AI05-0139: Generalized indexing to support iterators over containers
297 -- ??? Need to provide a more detailed spec of what this function does
299 function Try_Indexed_Call
303 Skip_First
: Boolean) return Boolean;
304 -- If a function has defaults for all its actuals, a call to it may in fact
305 -- be an indexing on the result of the call. Try_Indexed_Call attempts the
306 -- interpretation as an indexing, prior to analysis as a call. If both are
307 -- possible, the node is overloaded with both interpretations (same symbol
308 -- but two different types). If the call is written in prefix form, the
309 -- prefix becomes the first parameter in the call, and only the remaining
310 -- actuals must be checked for the presence of defaults.
312 function Try_Indirect_Call
315 Typ
: Entity_Id
) return Boolean;
316 -- Similarly, a function F that needs no actuals can return an access to a
317 -- subprogram, and the call F (X) interpreted as F.all (X). In this case
318 -- the call may be overloaded with both interpretations.
320 procedure wpo
(T
: Entity_Id
);
321 pragma Warnings
(Off
, wpo
);
322 -- Used for debugging: obtain list of primitive operations even if
323 -- type is not frozen and dispatch table is not built yet.
325 ------------------------
326 -- Ambiguous_Operands --
327 ------------------------
329 procedure Ambiguous_Operands
(N
: Node_Id
) is
330 procedure List_Operand_Interps
(Opnd
: Node_Id
);
332 --------------------------
333 -- List_Operand_Interps --
334 --------------------------
336 procedure List_Operand_Interps
(Opnd
: Node_Id
) is
337 Nam
: Node_Id
:= Empty
;
341 if Is_Overloaded
(Opnd
) then
342 if Nkind
(Opnd
) in N_Op
then
345 elsif Nkind
(Opnd
) = N_Function_Call
then
348 elsif Ada_Version
>= Ada_2012
then
354 Get_First_Interp
(Opnd
, I
, It
);
355 while Present
(It
.Nam
) loop
356 if Has_Implicit_Dereference
(It
.Typ
) then
358 ("can be interpreted as implicit dereference", Opnd
);
362 Get_Next_Interp
(I
, It
);
373 if Opnd
= Left_Opnd
(N
) then
375 ("\left operand has the following interpretations", N
);
378 ("\right operand has the following interpretations", N
);
382 List_Interps
(Nam
, Err
);
383 end List_Operand_Interps
;
385 -- Start of processing for Ambiguous_Operands
388 if Nkind
(N
) in N_Membership_Test
then
389 Error_Msg_N
("ambiguous operands for membership", N
);
391 elsif Nkind
(N
) in N_Op_Eq | N_Op_Ne
then
392 Error_Msg_N
("ambiguous operands for equality", N
);
395 Error_Msg_N
("ambiguous operands for comparison", N
);
398 if All_Errors_Mode
then
399 List_Operand_Interps
(Left_Opnd
(N
));
400 List_Operand_Interps
(Right_Opnd
(N
));
402 Error_Msg_N
("\use -gnatf switch for details", N
);
404 end Ambiguous_Operands
;
406 -----------------------
407 -- Analyze_Aggregate --
408 -----------------------
410 -- Most of the analysis of Aggregates requires that the type be known, and
411 -- is therefore put off until resolution of the context. Delta aggregates
412 -- have a base component that determines the enclosing aggregate type so
413 -- its type can be ascertained earlier. This also allows delta aggregates
414 -- to appear in the context of a record type with a private extension, as
415 -- per the latest update of AI12-0127.
417 procedure Analyze_Aggregate
(N
: Node_Id
) is
419 if No
(Etype
(N
)) then
420 if Nkind
(N
) = N_Delta_Aggregate
then
422 Base
: constant Node_Id
:= Expression
(N
);
430 -- If the base is overloaded, propagate interpretations to the
431 -- enclosing aggregate.
433 if Is_Overloaded
(Base
) then
434 Get_First_Interp
(Base
, I
, It
);
435 Set_Etype
(N
, Any_Type
);
437 while Present
(It
.Nam
) loop
438 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
439 Get_Next_Interp
(I
, It
);
443 Set_Etype
(N
, Etype
(Base
));
448 Set_Etype
(N
, Any_Composite
);
451 end Analyze_Aggregate
;
453 -----------------------
454 -- Analyze_Allocator --
455 -----------------------
457 procedure Analyze_Allocator
(N
: Node_Id
) is
458 Loc
: constant Source_Ptr
:= Sloc
(N
);
459 Sav_Errs
: constant Nat
:= Serious_Errors_Detected
;
460 E
: Node_Id
:= Expression
(N
);
461 Acc_Type
: Entity_Id
;
468 -- Deal with allocator restrictions
470 -- In accordance with H.4(7), the No_Allocators restriction only applies
471 -- to user-written allocators. The same consideration applies to the
472 -- No_Standard_Allocators_Before_Elaboration restriction.
474 if Comes_From_Source
(N
) then
475 Check_Restriction
(No_Allocators
, N
);
477 -- Processing for No_Standard_Allocators_After_Elaboration, loop to
478 -- look at enclosing context, checking task/main subprogram case.
482 while Present
(P
) loop
484 -- For the task case we need a handled sequence of statements,
485 -- where the occurrence of the allocator is within the statements
486 -- and the parent is a task body
488 if Nkind
(P
) = N_Handled_Sequence_Of_Statements
489 and then Is_List_Member
(C
)
490 and then List_Containing
(C
) = Statements
(P
)
492 Onode
:= Original_Node
(Parent
(P
));
494 -- Check for allocator within task body, this is a definite
495 -- violation of No_Allocators_After_Elaboration we can detect
498 if Nkind
(Onode
) = N_Task_Body
then
500 (No_Standard_Allocators_After_Elaboration
, N
);
505 -- The other case is appearance in a subprogram body. This is
506 -- a violation if this is a library level subprogram with no
507 -- parameters. Note that this is now a static error even if the
508 -- subprogram is not the main program (this is a change, in an
509 -- earlier version only the main program was affected, and the
510 -- check had to be done in the binder).
512 if Nkind
(P
) = N_Subprogram_Body
513 and then Nkind
(Parent
(P
)) = N_Compilation_Unit
514 and then No
(Parameter_Specifications
(Specification
(P
)))
517 (No_Standard_Allocators_After_Elaboration
, N
);
525 -- Ada 2012 (AI05-0111-3): Analyze the subpool_specification, if
526 -- any. The expected type for the name is any type. A non-overloading
527 -- rule then requires it to be of a type descended from
528 -- System.Storage_Pools.Subpools.Subpool_Handle.
530 -- This isn't exactly what the AI says, but it seems to be the right
531 -- rule. The AI should be fixed.???
534 Subpool
: constant Node_Id
:= Subpool_Handle_Name
(N
);
537 if Present
(Subpool
) then
540 if Is_Overloaded
(Subpool
) then
541 Error_Msg_N
("ambiguous subpool handle", Subpool
);
544 -- Check that Etype (Subpool) is descended from Subpool_Handle
550 -- Analyze the qualified expression or subtype indication
552 if Nkind
(E
) = N_Qualified_Expression
then
553 Acc_Type
:= Create_Itype
(E_Allocator_Type
, N
);
554 Set_Etype
(Acc_Type
, Acc_Type
);
555 Find_Type
(Subtype_Mark
(E
));
557 -- Analyze the qualified expression, and apply the name resolution
558 -- rule given in 4.7(3).
561 Type_Id
:= Etype
(E
);
562 Set_Directly_Designated_Type
(Acc_Type
, Type_Id
);
564 -- A qualified expression requires an exact match of the type,
565 -- class-wide matching is not allowed.
567 -- if Is_Class_Wide_Type (Type_Id)
568 -- and then Base_Type
569 -- (Etype (Expression (E))) /= Base_Type (Type_Id)
571 -- Wrong_Type (Expression (E), Type_Id);
574 -- We don't analyze the qualified expression itself because it's
575 -- part of the allocator. It is fully analyzed and resolved when
576 -- the allocator is resolved with the context type.
578 Set_Etype
(E
, Type_Id
);
580 -- Case where allocator has a subtype indication
583 -- If the allocator includes a N_Subtype_Indication then a
584 -- constraint is present, otherwise the node is a subtype mark.
585 -- Introduce an explicit subtype declaration into the tree
586 -- defining some anonymous subtype and rewrite the allocator to
587 -- use this subtype rather than the subtype indication.
589 -- It is important to introduce the explicit subtype declaration
590 -- so that the bounds of the subtype indication are attached to
591 -- the tree in case the allocator is inside a generic unit.
593 -- Finally, if there is no subtype indication and the type is
594 -- a tagged unconstrained type with discriminants, the designated
595 -- object is constrained by their default values, and it is
596 -- simplest to introduce an explicit constraint now. In some cases
597 -- this is done during expansion, but freeze actions are certain
598 -- to be emitted in the proper order if constraint is explicit.
600 if Is_Entity_Name
(E
) and then Expander_Active
then
602 Type_Id
:= Entity
(E
);
604 if Is_Tagged_Type
(Type_Id
)
605 and then Has_Defaulted_Discriminants
(Type_Id
)
606 and then not Is_Constrained
(Type_Id
)
609 Constr
: constant List_Id
:= New_List
;
610 Loc
: constant Source_Ptr
:= Sloc
(E
);
611 Discr
: Entity_Id
:= First_Discriminant
(Type_Id
);
614 while Present
(Discr
) loop
615 Append
(Discriminant_Default_Value
(Discr
), Constr
);
616 Next_Discriminant
(Discr
);
620 Make_Subtype_Indication
(Loc
,
621 Subtype_Mark
=> New_Occurrence_Of
(Type_Id
, Loc
),
623 Make_Index_Or_Discriminant_Constraint
(Loc
,
624 Constraints
=> Constr
)));
629 if Nkind
(E
) = N_Subtype_Indication
then
632 Base_Typ
: Entity_Id
;
635 -- A constraint is only allowed for a composite type in Ada
636 -- 95. In Ada 83, a constraint is also allowed for an
637 -- access-to-composite type, but the constraint is ignored.
639 Find_Type
(Subtype_Mark
(E
));
640 Base_Typ
:= Entity
(Subtype_Mark
(E
));
642 if Is_Elementary_Type
(Base_Typ
) then
643 if not (Ada_Version
= Ada_83
644 and then Is_Access_Type
(Base_Typ
))
646 Error_Msg_N
("constraint not allowed here", E
);
648 if Nkind
(Constraint
(E
)) =
649 N_Index_Or_Discriminant_Constraint
651 Error_Msg_N
-- CODEFIX
652 ("\if qualified expression was meant, " &
653 "use apostrophe", Constraint
(E
));
657 -- Get rid of the bogus constraint:
659 Rewrite
(E
, New_Copy_Tree
(Subtype_Mark
(E
)));
660 Analyze_Allocator
(N
);
664 -- In GNATprove mode we need to preserve the link between
665 -- the original subtype indication and the anonymous subtype,
666 -- to extend proofs to constrained access types. We only do
667 -- that outside of spec expressions, otherwise the declaration
668 -- cannot be inserted and analyzed. In such a case, GNATprove
669 -- later rejects the allocator as it is not used here in
670 -- a non-interfering context (SPARK 4.8(2) and 7.1.3(10)).
673 or else (GNATprove_Mode
and then not In_Spec_Expression
)
675 Def_Id
:= Make_Temporary
(Loc
, 'S');
678 Subtype_Decl
: constant Node_Id
:=
679 Make_Subtype_Declaration
(Loc
,
680 Defining_Identifier
=> Def_Id
,
681 Subtype_Indication
=> Relocate_Node
(E
));
683 Insert_Action
(E
, Subtype_Decl
);
685 -- Handle unusual case where Insert_Action does not
686 -- analyze the declaration. Subtype_Decl must be
687 -- preanalyzed before call to Process_Subtype below.
688 Preanalyze
(Subtype_Decl
);
691 if Sav_Errs
/= Serious_Errors_Detected
692 and then Nkind
(Constraint
(E
)) =
693 N_Index_Or_Discriminant_Constraint
695 Error_Msg_N
-- CODEFIX
696 ("if qualified expression was meant, use apostrophe!",
700 E
:= New_Occurrence_Of
(Def_Id
, Loc
);
701 Rewrite
(Expression
(N
), E
);
706 Type_Id
:= Process_Subtype
(E
, N
);
707 Acc_Type
:= Create_Itype
(E_Allocator_Type
, N
);
708 Set_Etype
(Acc_Type
, Acc_Type
);
709 Set_Directly_Designated_Type
(Acc_Type
, Type_Id
);
710 Check_Fully_Declared
(Type_Id
, N
);
712 -- Ada 2005 (AI-231): If the designated type is itself an access
713 -- type that excludes null, its default initialization will
714 -- be a null object, and we can insert an unconditional raise
715 -- before the allocator.
717 -- Ada 2012 (AI-104): A not null indication here is altogether
720 if Can_Never_Be_Null
(Type_Id
) then
721 if Expander_Active
then
722 Apply_Compile_Time_Constraint_Error
723 (N
, "null value not allowed here??", CE_Null_Not_Allowed
);
725 elsif Warn_On_Ada_2012_Compatibility
then
727 ("null value not allowed here in Ada 2012?y?", E
);
731 -- Check for missing initialization. Skip this check if the allocator
732 -- is made for a special return object or if we already had errors on
733 -- analyzing the allocator since, in that case, these are very likely
736 if not Is_Definite_Subtype
(Type_Id
)
737 and then not For_Special_Return_Object
(N
)
738 and then Serious_Errors_Detected
= Sav_Errs
740 if Is_Class_Wide_Type
(Type_Id
) then
742 ("initialization required in class-wide allocation", N
);
745 if Ada_Version
< Ada_2005
746 and then Is_Limited_Type
(Type_Id
)
748 Error_Msg_N
("unconstrained allocation not allowed", N
);
750 if Is_Array_Type
(Type_Id
) then
752 ("\constraint with array bounds required", N
);
754 elsif Has_Unknown_Discriminants
(Type_Id
) then
757 else pragma Assert
(Has_Discriminants
(Type_Id
));
759 ("\constraint with discriminant values required", N
);
762 -- Limited Ada 2005 and general nonlimited case.
763 -- This is an error, except in the case of an
764 -- uninitialized allocator that is generated
765 -- for a build-in-place function return of a
766 -- discriminated but compile-time-known-size
770 if Is_Rewrite_Substitution
(N
)
771 and then Nkind
(Original_Node
(N
)) = N_Allocator
774 Qual
: constant Node_Id
:=
775 Expression
(Original_Node
(N
));
777 (Nkind
(Qual
) = N_Qualified_Expression
);
778 Call
: constant Node_Id
:= Expression
(Qual
);
780 (Is_Expanded_Build_In_Place_Call
(Call
));
787 ("uninitialized unconstrained allocation not "
790 if Is_Array_Type
(Type_Id
) then
792 ("\qualified expression or constraint with "
793 & "array bounds required", N
);
795 elsif Has_Unknown_Discriminants
(Type_Id
) then
796 Error_Msg_N
("\qualified expression required", N
);
798 else pragma Assert
(Has_Discriminants
(Type_Id
));
800 ("\qualified expression or constraint with "
801 & "discriminant values required", N
);
809 if Is_Abstract_Type
(Type_Id
) then
810 Error_Msg_N
("cannot allocate abstract object", E
);
813 Set_Etype
(N
, Acc_Type
);
815 -- If this is an allocator for the return stack, then no restriction may
816 -- be violated since it's just a low-level access to the primary stack.
818 if Nkind
(Parent
(N
)) = N_Object_Declaration
819 and then Is_Entity_Name
(Object_Definition
(Parent
(N
)))
820 and then Is_Access_Type
(Entity
(Object_Definition
(Parent
(N
))))
823 Pool
: constant Entity_Id
:=
824 Associated_Storage_Pool
825 (Root_Type
(Entity
(Object_Definition
(Parent
(N
)))));
828 if Present
(Pool
) and then Is_RTE
(Pool
, RE_RS_Pool
) then
834 if Has_Task
(Designated_Type
(Acc_Type
)) then
835 Check_Restriction
(No_Tasking
, N
);
836 Check_Restriction
(Max_Tasks
, N
);
837 Check_Restriction
(No_Task_Allocators
, N
);
840 -- Check restriction against dynamically allocated protected objects
842 if Has_Protected
(Designated_Type
(Acc_Type
)) then
843 Check_Restriction
(No_Protected_Type_Allocators
, N
);
846 -- AI05-0013-1: No_Nested_Finalization forbids allocators if the access
847 -- type is nested, and the designated type needs finalization. The rule
848 -- is conservative in that class-wide types need finalization.
850 if Needs_Finalization
(Designated_Type
(Acc_Type
))
851 and then not Is_Library_Level_Entity
(Acc_Type
)
853 Check_Restriction
(No_Nested_Finalization
, N
);
856 -- Check that an allocator of a nested access type doesn't create a
857 -- protected object when restriction No_Local_Protected_Objects applies.
859 if Has_Protected
(Designated_Type
(Acc_Type
))
860 and then not Is_Library_Level_Entity
(Acc_Type
)
862 Check_Restriction
(No_Local_Protected_Objects
, N
);
865 -- Likewise for No_Local_Timing_Events
867 if Has_Timing_Event
(Designated_Type
(Acc_Type
))
868 and then not Is_Library_Level_Entity
(Acc_Type
)
870 Check_Restriction
(No_Local_Timing_Events
, N
);
873 -- If the No_Streams restriction is set, check that the type of the
874 -- object is not, and does not contain, any subtype derived from
875 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
876 -- Has_Stream just for efficiency reasons. There is no point in
877 -- spending time on a Has_Stream check if the restriction is not set.
879 if Restriction_Check_Required
(No_Streams
) then
880 if Has_Stream
(Designated_Type
(Acc_Type
)) then
881 Check_Restriction
(No_Streams
, N
);
885 if not Is_Library_Level_Entity
(Acc_Type
) then
886 Check_Restriction
(No_Local_Allocators
, N
);
890 if Serious_Errors_Detected
> Sav_Errs
then
891 Set_Error_Posted
(N
);
892 Set_Etype
(N
, Any_Type
);
894 end Analyze_Allocator
;
896 ---------------------------
897 -- Analyze_Arithmetic_Op --
898 ---------------------------
900 procedure Analyze_Arithmetic_Op
(N
: Node_Id
) is
901 L
: constant Node_Id
:= Left_Opnd
(N
);
902 R
: constant Node_Id
:= Right_Opnd
(N
);
907 Set_Etype
(N
, Any_Type
);
908 Candidate_Type
:= Empty
;
910 Analyze_Expression
(L
);
911 Analyze_Expression
(R
);
913 -- If the entity is already set, the node is the instantiation of a
914 -- generic node with a non-local reference, or was manufactured by a
915 -- call to Make_Op_xxx. In either case the entity is known to be valid,
916 -- and we do not need to collect interpretations, instead we just get
917 -- the single possible interpretation.
919 if Present
(Entity
(N
)) then
922 if Ekind
(Op_Id
) = E_Operator
then
923 Find_Arithmetic_Types
(L
, R
, Op_Id
, N
);
925 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
928 -- Entity is not already set, so we do need to collect interpretations
931 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
932 while Present
(Op_Id
) loop
933 if Ekind
(Op_Id
) = E_Operator
934 and then Present
(Next_Entity
(First_Entity
(Op_Id
)))
936 Find_Arithmetic_Types
(L
, R
, Op_Id
, N
);
938 -- The following may seem superfluous, because an operator cannot
939 -- be generic, but this ignores the cleverness of the author of
942 elsif Is_Overloadable
(Op_Id
) then
943 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
946 Op_Id
:= Homonym
(Op_Id
);
951 Check_Function_Writable_Actuals
(N
);
952 end Analyze_Arithmetic_Op
;
958 -- Function, procedure, and entry calls are checked here. The Name in
959 -- the call may be overloaded. The actuals have been analyzed and may
960 -- themselves be overloaded. On exit from this procedure, the node N
961 -- may have zero, one or more interpretations. In the first case an
962 -- error message is produced. In the last case, the node is flagged
963 -- as overloaded and the interpretations are collected in All_Interp.
965 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
966 -- the type-checking is similar to that of other calls.
968 procedure Analyze_Call
(N
: Node_Id
) is
969 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
970 Loc
: constant Source_Ptr
:= Sloc
(N
);
974 Nam_Ent
: Entity_Id
:= Empty
;
975 Success
: Boolean := False;
977 Deref
: Boolean := False;
978 -- Flag indicates whether an interpretation of the prefix is a
979 -- parameterless call that returns an access_to_subprogram.
981 procedure Check_Writable_Actuals
(N
: Node_Id
);
982 -- If the call has out or in-out parameters then mark its outermost
983 -- enclosing construct as a node on which the writable actuals check
984 -- must be performed.
986 function Name_Denotes_Function
return Boolean;
987 -- If the type of the name is an access to subprogram, this may be the
988 -- type of a name, or the return type of the function being called. If
989 -- the name is not an entity then it can denote a protected function.
990 -- Until we distinguish Etype from Return_Type, we must use this routine
991 -- to resolve the meaning of the name in the call.
993 procedure No_Interpretation
;
994 -- Output error message when no valid interpretation exists
996 ----------------------------
997 -- Check_Writable_Actuals --
998 ----------------------------
1000 -- The identification of conflicts in calls to functions with writable
1001 -- actuals is performed in the analysis phase of the front end to ensure
1002 -- that it reports exactly the same errors compiling with and without
1003 -- expansion enabled. It is performed in two stages:
1005 -- 1) When a call to a function with out-mode parameters is found,
1006 -- we climb to the outermost enclosing construct that can be
1007 -- evaluated in arbitrary order and we mark it with the flag
1010 -- 2) When the analysis of the marked node is complete, we traverse
1011 -- its decorated subtree searching for conflicts (see function
1012 -- Sem_Util.Check_Function_Writable_Actuals).
1014 -- The unique exception to this general rule is for aggregates, since
1015 -- their analysis is performed by the front end in the resolution
1016 -- phase. For aggregates we do not climb to their enclosing construct:
1017 -- we restrict the analysis to the subexpressions initializing the
1018 -- aggregate components.
1020 -- This implies that the analysis of expressions containing aggregates
1021 -- is not complete, since there may be conflicts on writable actuals
1022 -- involving subexpressions of the enclosing logical or arithmetic
1023 -- expressions. However, we cannot wait and perform the analysis when
1024 -- the whole subtree is resolved, since the subtrees may be transformed,
1025 -- thus adding extra complexity and computation cost to identify and
1026 -- report exactly the same errors compiling with and without expansion
1029 procedure Check_Writable_Actuals
(N
: Node_Id
) is
1031 if Comes_From_Source
(N
)
1032 and then Present
(Get_Subprogram_Entity
(N
))
1033 and then Has_Out_Or_In_Out_Parameter
(Get_Subprogram_Entity
(N
))
1035 -- For procedures and entries there is no need to climb since
1036 -- we only need to check if the actuals of this call invoke
1037 -- functions whose out-mode parameters overlap.
1039 if Nkind
(N
) /= N_Function_Call
then
1040 Set_Check_Actuals
(N
);
1042 -- For calls to functions we climb to the outermost enclosing
1043 -- construct where the out-mode actuals of this function may
1044 -- introduce conflicts.
1048 Outermost
: Node_Id
:= Empty
; -- init to avoid warning
1052 while Present
(P
) loop
1053 -- For object declarations we can climb to the node from
1054 -- its object definition branch or from its initializing
1055 -- expression. We prefer to mark the child node as the
1056 -- outermost construct to avoid adding further complexity
1057 -- to the routine that will later take care of
1058 -- performing the writable actuals check.
1060 if Has_Arbitrary_Evaluation_Order
(Nkind
(P
))
1061 and then Nkind
(P
) not in
1062 N_Assignment_Statement | N_Object_Declaration
1067 -- Avoid climbing more than needed
1069 exit when Stop_Subtree_Climbing
(Nkind
(P
))
1070 or else (Nkind
(P
) = N_Range
1072 Nkind
(Parent
(P
)) not in N_In | N_Not_In
);
1077 Set_Check_Actuals
(Outermost
);
1081 end Check_Writable_Actuals
;
1083 ---------------------------
1084 -- Name_Denotes_Function --
1085 ---------------------------
1087 function Name_Denotes_Function
return Boolean is
1089 if Is_Entity_Name
(Nam
) then
1090 return Ekind
(Entity
(Nam
)) = E_Function
;
1091 elsif Nkind
(Nam
) = N_Selected_Component
then
1092 return Ekind
(Entity
(Selector_Name
(Nam
))) = E_Function
;
1096 end Name_Denotes_Function
;
1098 -----------------------
1099 -- No_Interpretation --
1100 -----------------------
1102 procedure No_Interpretation
is
1103 L
: constant Boolean := Is_List_Member
(N
);
1104 K
: constant Node_Kind
:= Nkind
(Parent
(N
));
1107 -- If the node is in a list whose parent is not an expression then it
1108 -- must be an attempted procedure call.
1110 if L
and then K
not in N_Subexpr
then
1111 if Ekind
(Entity
(Nam
)) = E_Generic_Procedure
then
1113 ("must instantiate generic procedure& before call",
1116 Error_Msg_N
("procedure or entry name expected", Nam
);
1119 -- Check for tasking cases where only an entry call will do
1122 and then K
in N_Entry_Call_Alternative | N_Triggering_Alternative
1124 Error_Msg_N
("entry name expected", Nam
);
1126 -- Otherwise give general error message
1129 Error_Msg_N
("invalid prefix in call", Nam
);
1131 end No_Interpretation
;
1133 -- Start of processing for Analyze_Call
1136 -- Initialize the type of the result of the call to the error type,
1137 -- which will be reset if the type is successfully resolved.
1139 Set_Etype
(N
, Any_Type
);
1143 if not Is_Overloaded
(Nam
) then
1145 -- Only one interpretation to check
1147 if Ekind
(Etype
(Nam
)) = E_Subprogram_Type
then
1148 Nam_Ent
:= Etype
(Nam
);
1150 -- If the prefix is an access_to_subprogram, this may be an indirect
1151 -- call. This is the case if the name in the call is not an entity
1152 -- name, or if it is a function name in the context of a procedure
1153 -- call. In this latter case, we have a call to a parameterless
1154 -- function that returns a pointer_to_procedure which is the entity
1155 -- being called. Finally, F (X) may be a call to a parameterless
1156 -- function that returns a pointer to a function with parameters.
1157 -- Note that if F returns an access-to-subprogram whose designated
1158 -- type is an array, F (X) cannot be interpreted as an indirect call
1159 -- through the result of the call to F.
1161 elsif Is_Access_Subprogram_Type
(Base_Type
(Etype
(Nam
)))
1163 (not Name_Denotes_Function
1164 or else Nkind
(N
) = N_Procedure_Call_Statement
1166 (Nkind
(Parent
(N
)) /= N_Explicit_Dereference
1167 and then Is_Entity_Name
(Nam
)
1168 and then No
(First_Formal
(Entity
(Nam
)))
1170 Is_Array_Type
(Etype
(Designated_Type
(Etype
(Nam
))))
1171 and then Present
(Actuals
)))
1173 Nam_Ent
:= Designated_Type
(Etype
(Nam
));
1174 Insert_Explicit_Dereference
(Nam
);
1176 -- Selected component case. Simple entry or protected operation,
1177 -- where the entry name is given by the selector name.
1179 elsif Nkind
(Nam
) = N_Selected_Component
then
1180 Nam_Ent
:= Entity
(Selector_Name
(Nam
));
1182 if Ekind
(Nam_Ent
) not in E_Entry
1187 Error_Msg_N
("name in call is not a callable entity", Nam
);
1188 Set_Etype
(N
, Any_Type
);
1192 -- If the name is an Indexed component, it can be a call to a member
1193 -- of an entry family. The prefix must be a selected component whose
1194 -- selector is the entry. Analyze_Procedure_Call normalizes several
1195 -- kinds of call into this form.
1197 elsif Nkind
(Nam
) = N_Indexed_Component
then
1198 if Nkind
(Prefix
(Nam
)) = N_Selected_Component
then
1199 Nam_Ent
:= Entity
(Selector_Name
(Prefix
(Nam
)));
1201 Error_Msg_N
("name in call is not a callable entity", Nam
);
1202 Set_Etype
(N
, Any_Type
);
1206 elsif not Is_Entity_Name
(Nam
) then
1207 Error_Msg_N
("name in call is not a callable entity", Nam
);
1208 Set_Etype
(N
, Any_Type
);
1212 Nam_Ent
:= Entity
(Nam
);
1214 -- If not overloadable, this may be a generalized indexing
1215 -- operation with named associations. Rewrite again as an
1216 -- indexed component and analyze as container indexing.
1218 if not Is_Overloadable
(Nam_Ent
) then
1220 (Find_Value_Of_Aspect
1221 (Etype
(Nam_Ent
), Aspect_Constant_Indexing
))
1224 Make_Indexed_Component
(Sloc
(N
),
1226 Expressions
=> Parameter_Associations
(N
)));
1228 if Try_Container_Indexing
(N
, Nam
, Expressions
(N
)) then
1242 -- Operations generated for RACW stub types are called only through
1243 -- dispatching, and can never be the static interpretation of a call.
1245 if Is_RACW_Stub_Type_Operation
(Nam_Ent
) then
1250 Analyze_One_Call
(N
, Nam_Ent
, True, Success
);
1252 -- If the nonoverloaded interpretation is a call to an abstract
1253 -- nondispatching operation, then flag an error and return.
1255 if Is_Overloadable
(Nam_Ent
)
1256 and then Is_Abstract_Subprogram
(Nam_Ent
)
1257 and then not Is_Dispatching_Operation
(Nam_Ent
)
1259 Nondispatching_Call_To_Abstract_Operation
(N
, Nam_Ent
);
1263 -- If this is an indirect call, the return type of the access_to
1264 -- subprogram may be an incomplete type. At the point of the call,
1265 -- use the full type if available, and at the same time update the
1266 -- return type of the access_to_subprogram.
1269 and then Nkind
(Nam
) = N_Explicit_Dereference
1270 and then Ekind
(Etype
(N
)) = E_Incomplete_Type
1271 and then Present
(Full_View
(Etype
(N
)))
1273 Set_Etype
(N
, Full_View
(Etype
(N
)));
1274 Set_Etype
(Nam_Ent
, Etype
(N
));
1280 -- An overloaded selected component must denote overloaded operations
1281 -- of a concurrent type. The interpretations are attached to the
1282 -- simple name of those operations.
1284 if Nkind
(Nam
) = N_Selected_Component
then
1285 Nam
:= Selector_Name
(Nam
);
1288 Get_First_Interp
(Nam
, X
, It
);
1289 while Present
(It
.Nam
) loop
1293 -- Name may be call that returns an access to subprogram, or more
1294 -- generally an overloaded expression one of whose interpretations
1295 -- yields an access to subprogram. If the name is an entity, we do
1296 -- not dereference, because the node is a call that returns the
1297 -- access type: note difference between f(x), where the call may
1298 -- return an access subprogram type, and f(x)(y), where the type
1299 -- returned by the call to f is implicitly dereferenced to analyze
1302 if Is_Access_Type
(Nam_Ent
) then
1303 Nam_Ent
:= Designated_Type
(Nam_Ent
);
1305 elsif Is_Access_Type
(Etype
(Nam_Ent
))
1307 (not Is_Entity_Name
(Nam
)
1308 or else Nkind
(N
) = N_Procedure_Call_Statement
)
1309 and then Ekind
(Designated_Type
(Etype
(Nam_Ent
)))
1312 Nam_Ent
:= Designated_Type
(Etype
(Nam_Ent
));
1314 if Is_Entity_Name
(Nam
) then
1319 -- If the call has been rewritten from a prefixed call, the first
1320 -- parameter has been analyzed, but may need a subsequent
1321 -- dereference, so skip its analysis now.
1323 if Is_Rewrite_Substitution
(N
)
1324 and then Nkind
(Original_Node
(N
)) = Nkind
(N
)
1325 and then Nkind
(Name
(N
)) /= Nkind
(Name
(Original_Node
(N
)))
1326 and then Present
(Parameter_Associations
(N
))
1327 and then Present
(Etype
(First
(Parameter_Associations
(N
))))
1330 (N
, Nam_Ent
, False, Success
, Skip_First
=> True);
1332 Analyze_One_Call
(N
, Nam_Ent
, False, Success
);
1335 -- If the interpretation succeeds, mark the proper type of the
1336 -- prefix (any valid candidate will do). If not, remove the
1337 -- candidate interpretation. If this is a parameterless call
1338 -- on an anonymous access to subprogram, X is a variable with
1339 -- an access discriminant D, the entity in the interpretation is
1340 -- D, so rewrite X as X.D.all.
1344 and then Nkind
(Parent
(N
)) /= N_Explicit_Dereference
1346 if Ekind
(It
.Nam
) = E_Discriminant
1347 and then Has_Implicit_Dereference
(It
.Nam
)
1350 Make_Explicit_Dereference
(Loc
,
1352 Make_Selected_Component
(Loc
,
1354 New_Occurrence_Of
(Entity
(Nam
), Loc
),
1356 New_Occurrence_Of
(It
.Nam
, Loc
))));
1362 Set_Entity
(Nam
, It
.Nam
);
1363 Insert_Explicit_Dereference
(Nam
);
1364 Set_Etype
(Nam
, Nam_Ent
);
1368 Set_Etype
(Nam
, It
.Typ
);
1371 elsif Nkind
(Name
(N
)) in N_Function_Call | N_Selected_Component
1376 Get_Next_Interp
(X
, It
);
1379 -- If the name is the result of a function call, it can only be a
1380 -- call to a function returning an access to subprogram. Insert
1381 -- explicit dereference.
1383 if Nkind
(Nam
) = N_Function_Call
then
1384 Insert_Explicit_Dereference
(Nam
);
1387 if Etype
(N
) = Any_Type
then
1389 -- None of the interpretations is compatible with the actuals
1391 Diagnose_Call
(N
, Nam
);
1393 -- Special checks for uninstantiated put routines
1395 if Nkind
(N
) = N_Procedure_Call_Statement
1396 and then Is_Entity_Name
(Nam
)
1397 and then Chars
(Nam
) = Name_Put
1398 and then List_Length
(Actuals
) = 1
1401 Arg
: constant Node_Id
:= First
(Actuals
);
1405 if Nkind
(Arg
) = N_Parameter_Association
then
1406 Typ
:= Etype
(Explicit_Actual_Parameter
(Arg
));
1411 if Is_Signed_Integer_Type
(Typ
) then
1413 ("possible missing instantiation of "
1414 & "'Text_'I'O.'Integer_'I'O!", Nam
);
1416 elsif Is_Modular_Integer_Type
(Typ
) then
1418 ("possible missing instantiation of "
1419 & "'Text_'I'O.'Modular_'I'O!", Nam
);
1421 elsif Is_Floating_Point_Type
(Typ
) then
1423 ("possible missing instantiation of "
1424 & "'Text_'I'O.'Float_'I'O!", Nam
);
1426 elsif Is_Ordinary_Fixed_Point_Type
(Typ
) then
1428 ("possible missing instantiation of "
1429 & "'Text_'I'O.'Fixed_'I'O!", Nam
);
1431 elsif Is_Decimal_Fixed_Point_Type
(Typ
) then
1433 ("possible missing instantiation of "
1434 & "'Text_'I'O.'Decimal_'I'O!", Nam
);
1436 elsif Is_Enumeration_Type
(Typ
) then
1438 ("possible missing instantiation of "
1439 & "'Text_'I'O.'Enumeration_'I'O!", Nam
);
1444 elsif not Is_Overloaded
(N
)
1445 and then Is_Entity_Name
(Nam
)
1447 -- Resolution yields a single interpretation. Verify that the
1448 -- reference has capitalization consistent with the declaration.
1450 Set_Entity_With_Checks
(Nam
, Entity
(Nam
));
1451 Generate_Reference
(Entity
(Nam
), Nam
);
1453 Set_Etype
(Nam
, Etype
(Entity
(Nam
)));
1455 Remove_Abstract_Operations
(N
);
1459 -- Check the accessibility level for actuals for explicitly aliased
1460 -- formals when a function call appears within a return statement.
1461 -- This is only checked if the enclosing subprogram Comes_From_Source,
1462 -- to avoid issuing errors on calls occurring in wrapper subprograms
1463 -- (for example, where the call is part of an expression of an aspect
1464 -- associated with a wrapper, such as Pre'Class).
1466 if Nkind
(N
) = N_Function_Call
1467 and then Comes_From_Source
(N
)
1468 and then Present
(Nam_Ent
)
1469 and then In_Return_Value
(N
)
1470 and then Comes_From_Source
(Current_Subprogram
)
1476 Act
:= First_Actual
(N
);
1477 Form
:= First_Formal
(Nam_Ent
);
1479 while Present
(Form
) and then Present
(Act
) loop
1480 -- Check whether the formal is aliased and if the accessibility
1481 -- level of the actual is deeper than the accessibility level
1482 -- of the enclosing subprogram to which the current return
1483 -- statement applies.
1485 -- Should we be checking Is_Entity_Name on Act? Won't this miss
1488 if Is_Explicitly_Aliased
(Form
)
1489 and then Is_Entity_Name
(Act
)
1490 and then Static_Accessibility_Level
1491 (Act
, Zero_On_Dynamic_Level
)
1492 > Subprogram_Access_Level
(Current_Subprogram
)
1494 Error_Msg_N
("actual for explicitly aliased formal is too"
1495 & " short lived", Act
);
1504 if Ada_Version
>= Ada_2012
then
1506 -- Check if the call contains a function with writable actuals
1508 Check_Writable_Actuals
(N
);
1510 -- If found and the outermost construct that can be evaluated in
1511 -- an arbitrary order is precisely this call, then check all its
1514 Check_Function_Writable_Actuals
(N
);
1516 -- The return type of the function may be incomplete. This can be
1517 -- the case if the type is a generic formal, or a limited view. It
1518 -- can also happen when the function declaration appears before the
1519 -- full view of the type (which is legal in Ada 2012) and the call
1520 -- appears in a different unit, in which case the incomplete view
1521 -- must be replaced with the full view (or the nonlimited view)
1522 -- to prevent subsequent type errors. Note that the usual install/
1523 -- removal of limited_with clauses is not sufficient to handle this
1524 -- case, because the limited view may have been captured in another
1525 -- compilation unit that defines the current function.
1527 if Is_Incomplete_Type
(Etype
(N
)) then
1528 if Present
(Full_View
(Etype
(N
))) then
1529 if Is_Entity_Name
(Nam
) then
1530 Set_Etype
(Nam
, Full_View
(Etype
(N
)));
1531 Set_Etype
(Entity
(Nam
), Full_View
(Etype
(N
)));
1534 Set_Etype
(N
, Full_View
(Etype
(N
)));
1536 -- If the call is within a thunk, the nonlimited view should be
1537 -- analyzed eventually (see also Analyze_Return_Type).
1539 elsif From_Limited_With
(Etype
(N
))
1540 and then Present
(Non_Limited_View
(Etype
(N
)))
1542 (Ekind
(Non_Limited_View
(Etype
(N
))) /= E_Incomplete_Type
1543 or else Is_Thunk
(Current_Scope
))
1545 Set_Etype
(N
, Non_Limited_View
(Etype
(N
)));
1547 -- If there is no completion for the type, this may be because
1548 -- there is only a limited view of it and there is nothing in
1549 -- the context of the current unit that has required a regular
1550 -- compilation of the unit containing the type. We recognize
1551 -- this unusual case by the fact that unit is not analyzed.
1552 -- Note that the call being analyzed is in a different unit from
1553 -- the function declaration, and nothing indicates that the type
1554 -- is a limited view.
1556 elsif Ekind
(Scope
(Etype
(N
))) = E_Package
1557 and then Present
(Limited_View
(Scope
(Etype
(N
))))
1558 and then not Analyzed
(Unit_Declaration_Node
(Scope
(Etype
(N
))))
1561 ("cannot call function that returns limited view of}",
1565 ("\there must be a regular with_clause for package & in the "
1566 & "current unit, or in some unit in its context",
1567 N
, Scope
(Etype
(N
)));
1569 Set_Etype
(N
, Any_Type
);
1575 -----------------------------
1576 -- Analyze_Case_Expression --
1577 -----------------------------
1579 procedure Analyze_Case_Expression
(N
: Node_Id
) is
1580 Expr
: constant Node_Id
:= Expression
(N
);
1581 First_Alt
: constant Node_Id
:= First
(Alternatives
(N
));
1583 First_Expr
: Node_Id
:= Empty
;
1584 -- First expression in the case where there is some type information
1585 -- available, i.e. there is not Any_Type everywhere, which can happen
1586 -- because of some error.
1588 Second_Expr
: Node_Id
:= Empty
;
1589 -- Second expression as above
1591 Wrong_Alt
: Node_Id
:= Empty
;
1592 -- For error reporting
1594 procedure Non_Static_Choice_Error
(Choice
: Node_Id
);
1595 -- Error routine invoked by the generic instantiation below when
1596 -- the case expression has a non static choice.
1598 procedure Check_Next_Expression
(T
: Entity_Id
; Alt
: Node_Id
);
1599 -- Check one interpretation of the next expression with type T
1601 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
; Alt
: Node_Id
);
1602 -- Check first expression with type T1 and next expression with type T2
1604 package Case_Choices_Analysis
is new
1605 Generic_Analyze_Choices
1606 (Process_Associated_Node
=> No_OP
);
1607 use Case_Choices_Analysis
;
1609 package Case_Choices_Checking
is new
1610 Generic_Check_Choices
1611 (Process_Empty_Choice
=> No_OP
,
1612 Process_Non_Static_Choice
=> Non_Static_Choice_Error
,
1613 Process_Associated_Node
=> No_OP
);
1614 use Case_Choices_Checking
;
1616 -----------------------------
1617 -- Non_Static_Choice_Error --
1618 -----------------------------
1620 procedure Non_Static_Choice_Error
(Choice
: Node_Id
) is
1622 Flag_Non_Static_Expr
1623 ("choice given in case expression is not static!", Choice
);
1624 end Non_Static_Choice_Error
;
1626 ---------------------------
1627 -- Check_Next_Expression --
1628 ---------------------------
1630 procedure Check_Next_Expression
(T
: Entity_Id
; Alt
: Node_Id
) is
1631 Next_Expr
: constant Node_Id
:= Expression
(Alt
);
1637 if Next_Expr
= First_Expr
then
1638 Check_Next_Expression
(T
, Next
(Alt
));
1642 -- Loop through the interpretations of the next expression
1644 if not Is_Overloaded
(Next_Expr
) then
1645 Check_Expression_Pair
(T
, Etype
(Next_Expr
), Alt
);
1648 Get_First_Interp
(Next_Expr
, I
, It
);
1649 while Present
(It
.Typ
) loop
1650 Check_Expression_Pair
(T
, It
.Typ
, Alt
);
1651 Get_Next_Interp
(I
, It
);
1654 end Check_Next_Expression
;
1656 ---------------------------
1657 -- Check_Expression_Pair --
1658 ---------------------------
1660 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
; Alt
: Node_Id
) is
1661 Next_Expr
: constant Node_Id
:= Expression
(Alt
);
1666 if Covers
(T1
=> T1
, T2
=> T2
)
1667 or else Covers
(T1
=> T2
, T2
=> T1
)
1669 T
:= Specific_Type
(T1
, T2
);
1671 elsif Is_User_Defined_Literal
(First_Expr
, T2
) then
1674 elsif Is_User_Defined_Literal
(Next_Expr
, T1
) then
1678 T
:= Possible_Type_For_Conditional_Expression
(T1
, T2
);
1686 if Present
(Next
(Alt
)) then
1687 Check_Next_Expression
(T
, Next
(Alt
));
1689 Add_One_Interp
(N
, T
, T
);
1691 end Check_Expression_Pair
;
1696 Exp_Type
: Entity_Id
;
1697 Exp_Btype
: Entity_Id
;
1700 Others_Present
: Boolean;
1702 -- Start of processing for Analyze_Case_Expression
1705 Analyze_And_Resolve
(Expr
, Any_Discrete
);
1706 Check_Unset_Reference
(Expr
);
1707 Exp_Type
:= Etype
(Expr
);
1708 Exp_Btype
:= Base_Type
(Exp_Type
);
1710 Set_Etype
(N
, Any_Type
);
1713 while Present
(Alt
) loop
1714 if Error_Posted
(Expression
(Alt
)) then
1718 Analyze_Expression
(Expression
(Alt
));
1720 if Etype
(Expression
(Alt
)) /= Any_Type
then
1721 if No
(First_Expr
) then
1722 First_Expr
:= Expression
(Alt
);
1724 elsif No
(Second_Expr
) then
1725 Second_Expr
:= Expression
(Alt
);
1732 -- Get our initial type from the first expression for which we got some
1733 -- useful type information from the expression.
1735 if No
(First_Expr
) then
1739 -- The expression must be of a discrete type which must be determinable
1740 -- independently of the context in which the expression occurs, but
1741 -- using the fact that the expression must be of a discrete type.
1742 -- Moreover, the type this expression must not be a character literal
1743 -- (which is always ambiguous).
1745 -- If error already reported by Resolve, nothing more to do
1747 if Exp_Btype
= Any_Discrete
or else Exp_Btype
= Any_Type
then
1750 -- Special case message for character literal
1752 elsif Exp_Btype
= Any_Character
then
1754 ("character literal as case expression is ambiguous", Expr
);
1758 -- If the case expression is a formal object of mode in out, then
1759 -- treat it as having a nonstatic subtype by forcing use of the base
1760 -- type (which has to get passed to Check_Case_Choices below). Also
1761 -- use base type when the case expression is parenthesized.
1763 if Paren_Count
(Expr
) > 0
1764 or else (Is_Entity_Name
(Expr
)
1765 and then Ekind
(Entity
(Expr
)) = E_Generic_In_Out_Parameter
)
1767 Exp_Type
:= Exp_Btype
;
1770 -- The case expression alternatives cover the range of a static subtype
1771 -- subject to aspect Static_Predicate. Do not check the choices when the
1772 -- case expression has not been fully analyzed yet because this may lead
1775 if Is_OK_Static_Subtype
(Exp_Type
)
1776 and then Has_Static_Predicate_Aspect
(Exp_Type
)
1777 and then In_Spec_Expression
1781 -- Call Analyze_Choices and Check_Choices to do the rest of the work
1784 Analyze_Choices
(Alternatives
(N
), Exp_Type
);
1785 Check_Choices
(N
, Alternatives
(N
), Exp_Type
, Others_Present
);
1787 if Exp_Type
= Universal_Integer
and then not Others_Present
then
1789 ("case on universal integer requires OTHERS choice", Expr
);
1794 -- RM 4.5.7(10/3): If the case_expression is the operand of a type
1795 -- conversion, the type of the case_expression is the target type
1796 -- of the conversion.
1798 if Nkind
(Parent
(N
)) = N_Type_Conversion
then
1799 Set_Etype
(N
, Etype
(Parent
(N
)));
1803 -- Loop through the interpretations of the first expression and check
1804 -- the other expressions if present.
1806 if not Is_Overloaded
(First_Expr
) then
1807 if Present
(Second_Expr
) then
1808 Check_Next_Expression
(Etype
(First_Expr
), First_Alt
);
1810 Set_Etype
(N
, Etype
(First_Expr
));
1814 Get_First_Interp
(First_Expr
, I
, It
);
1815 while Present
(It
.Typ
) loop
1816 if Present
(Second_Expr
) then
1817 Check_Next_Expression
(It
.Typ
, First_Alt
);
1819 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
1822 Get_Next_Interp
(I
, It
);
1826 -- If no possible interpretation has been found, the type of the wrong
1827 -- alternative doesn't match any interpretation of the FIRST expression.
1829 if Etype
(N
) = Any_Type
and then Present
(Wrong_Alt
) then
1830 Second_Expr
:= Expression
(Wrong_Alt
);
1832 if Is_Overloaded
(First_Expr
) then
1833 if Is_Overloaded
(Second_Expr
) then
1835 ("no interpretation compatible with those of previous "
1840 ("type incompatible with interpretations of previous "
1844 ("\this alternative has}!",
1846 Etype
(Second_Expr
));
1850 if Is_Overloaded
(Second_Expr
) then
1852 ("no interpretation compatible with type of previous "
1856 ("\previous alternative has}!",
1858 Etype
(First_Expr
));
1861 ("type incompatible with that of previous alternative",
1864 ("\previous alternative has}!",
1866 Etype
(First_Expr
));
1868 ("\this alternative has}!",
1870 Etype
(Second_Expr
));
1874 end Analyze_Case_Expression
;
1876 ---------------------------
1877 -- Analyze_Concatenation --
1878 ---------------------------
1880 procedure Analyze_Concatenation
(N
: Node_Id
) is
1882 -- We wish to avoid deep recursion, because concatenations are often
1883 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1884 -- operands nonrecursively until we find something that is not a
1885 -- concatenation (A in this case), or has already been analyzed. We
1886 -- analyze that, and then walk back up the tree following Parent
1887 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1888 -- work at each level. The Parent pointers allow us to avoid recursion,
1889 -- and thus avoid running out of memory.
1895 Candidate_Type
:= Empty
;
1897 -- The following code is equivalent to:
1899 -- Set_Etype (N, Any_Type);
1900 -- Analyze_Expression (Left_Opnd (N));
1901 -- Analyze_Concatenation_Rest (N);
1903 -- where the Analyze_Expression call recurses back here if the left
1904 -- operand is a concatenation.
1906 -- Walk down left operands
1909 Set_Etype
(NN
, Any_Type
);
1910 L
:= Left_Opnd
(NN
);
1911 exit when Nkind
(L
) /= N_Op_Concat
or else Analyzed
(L
);
1915 -- Now (given the above example) NN is A&B and L is A
1917 -- First analyze L ...
1919 Analyze_Expression
(L
);
1921 -- ... then walk NN back up until we reach N (where we started), calling
1922 -- Analyze_Concatenation_Rest along the way.
1925 Analyze_Concatenation_Rest
(NN
);
1929 end Analyze_Concatenation
;
1931 --------------------------------
1932 -- Analyze_Concatenation_Rest --
1933 --------------------------------
1935 -- If the only one-dimensional array type in scope is String,
1936 -- this is the resulting type of the operation. Otherwise there
1937 -- will be a concatenation operation defined for each user-defined
1938 -- one-dimensional array.
1940 procedure Analyze_Concatenation_Rest
(N
: Node_Id
) is
1941 L
: constant Node_Id
:= Left_Opnd
(N
);
1942 R
: constant Node_Id
:= Right_Opnd
(N
);
1943 Op_Id
: Entity_Id
:= Entity
(N
);
1948 Analyze_Expression
(R
);
1950 -- If the entity is present, the node appears in an instance, and
1951 -- denotes a predefined concatenation operation. The resulting type is
1952 -- obtained from the arguments when possible. If the arguments are
1953 -- aggregates, the array type and the concatenation type must be
1956 if Present
(Op_Id
) then
1957 if Ekind
(Op_Id
) = E_Operator
then
1958 LT
:= Base_Type
(Etype
(L
));
1959 RT
:= Base_Type
(Etype
(R
));
1961 if Is_Array_Type
(LT
)
1962 and then (RT
= LT
or else RT
= Base_Type
(Component_Type
(LT
)))
1964 Add_One_Interp
(N
, Op_Id
, LT
);
1966 elsif Is_Array_Type
(RT
)
1967 and then LT
= Base_Type
(Component_Type
(RT
))
1969 Add_One_Interp
(N
, Op_Id
, RT
);
1971 -- If one operand is a string type or a user-defined array type,
1972 -- and the other is a literal, result is of the specific type.
1975 (Root_Type
(LT
) = Standard_String
1976 or else Scope
(LT
) /= Standard_Standard
)
1977 and then Etype
(R
) = Any_String
1979 Add_One_Interp
(N
, Op_Id
, LT
);
1982 (Root_Type
(RT
) = Standard_String
1983 or else Scope
(RT
) /= Standard_Standard
)
1984 and then Etype
(L
) = Any_String
1986 Add_One_Interp
(N
, Op_Id
, RT
);
1988 elsif not Is_Generic_Type
(Etype
(Op_Id
)) then
1989 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
1992 -- Type and its operations must be visible
1994 Set_Entity
(N
, Empty
);
1995 Analyze_Concatenation
(N
);
1999 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
2003 Op_Id
:= Get_Name_Entity_Id
(Name_Op_Concat
);
2004 while Present
(Op_Id
) loop
2005 if Ekind
(Op_Id
) = E_Operator
then
2007 -- Do not consider operators declared in dead code, they
2008 -- cannot be part of the resolution.
2010 if Is_Eliminated
(Op_Id
) then
2013 Find_Concatenation_Types
(L
, R
, Op_Id
, N
);
2017 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
2020 Op_Id
:= Homonym
(Op_Id
);
2025 end Analyze_Concatenation_Rest
;
2027 ------------------------------------
2028 -- Analyze_Comparison_Equality_Op --
2029 ------------------------------------
2031 procedure Analyze_Comparison_Equality_Op
(N
: Node_Id
) is
2032 Loc
: constant Source_Ptr
:= Sloc
(N
);
2033 L
: constant Node_Id
:= Left_Opnd
(N
);
2034 R
: constant Node_Id
:= Right_Opnd
(N
);
2039 Set_Etype
(N
, Any_Type
);
2040 Candidate_Type
:= Empty
;
2042 Analyze_Expression
(L
);
2043 Analyze_Expression
(R
);
2045 -- If the entity is set, the node is a generic instance with a non-local
2046 -- reference to the predefined operator or to a user-defined function.
2047 -- It can also be an inequality that is expanded into the negation of a
2048 -- call to a user-defined equality operator.
2050 -- For the predefined case, the result is Boolean, regardless of the
2051 -- type of the operands. The operands may even be limited, if they are
2052 -- generic actuals. If they are overloaded, label the operands with the
2053 -- compare type if it is present, typically because it is a global type
2054 -- in a generic instance, or with the common type that must be present,
2055 -- or with the type of the formal of the user-defined function.
2057 if Present
(Entity
(N
)) then
2058 Op_Id
:= Entity
(N
);
2060 if Ekind
(Op_Id
) = E_Operator
then
2061 Add_One_Interp
(N
, Op_Id
, Standard_Boolean
);
2063 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
2066 if Is_Overloaded
(L
) then
2067 if Ekind
(Op_Id
) = E_Operator
then
2069 (if Present
(Compare_Type
(N
))
2070 then Compare_Type
(N
)
2071 else Intersect_Types
(L
, R
)));
2073 Set_Etype
(L
, Etype
(First_Formal
(Op_Id
)));
2077 if Is_Overloaded
(R
) then
2078 if Ekind
(Op_Id
) = E_Operator
then
2080 (if Present
(Compare_Type
(N
))
2081 then Compare_Type
(N
)
2082 else Intersect_Types
(L
, R
)));
2084 Set_Etype
(R
, Etype
(Next_Formal
(First_Formal
(Op_Id
))));
2089 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
2091 while Present
(Op_Id
) loop
2092 if Ekind
(Op_Id
) = E_Operator
then
2093 Find_Comparison_Equality_Types
(L
, R
, Op_Id
, N
);
2095 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
2098 Op_Id
:= Homonym
(Op_Id
);
2102 -- If there was no match and the operator is inequality, this may be
2103 -- a case where inequality has not been made explicit, as for tagged
2104 -- types. Analyze the node as the negation of an equality operation.
2105 -- This cannot be done earlier because, before analysis, we cannot rule
2106 -- out the presence of an explicit inequality.
2108 if Etype
(N
) = Any_Type
and then Nkind
(N
) = N_Op_Ne
then
2109 Op_Id
:= Get_Name_Entity_Id
(Name_Op_Eq
);
2111 while Present
(Op_Id
) loop
2112 if Ekind
(Op_Id
) = E_Operator
then
2113 Find_Comparison_Equality_Types
(L
, R
, Op_Id
, N
);
2115 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
2118 Op_Id
:= Homonym
(Op_Id
);
2121 if Etype
(N
) /= Any_Type
then
2122 Op_Id
:= Entity
(N
);
2128 Left_Opnd
=> Left_Opnd
(N
),
2129 Right_Opnd
=> Right_Opnd
(N
))));
2131 Set_Entity
(Right_Opnd
(N
), Op_Id
);
2137 Check_Function_Writable_Actuals
(N
);
2138 end Analyze_Comparison_Equality_Op
;
2140 ----------------------------------
2141 -- Analyze_Explicit_Dereference --
2142 ----------------------------------
2144 procedure Analyze_Explicit_Dereference
(N
: Node_Id
) is
2145 Loc
: constant Source_Ptr
:= Sloc
(N
);
2146 P
: constant Node_Id
:= Prefix
(N
);
2152 function Is_Function_Type
return Boolean;
2153 -- Check whether node may be interpreted as an implicit function call
2155 ----------------------
2156 -- Is_Function_Type --
2157 ----------------------
2159 function Is_Function_Type
return Boolean is
2164 if not Is_Overloaded
(N
) then
2165 return Ekind
(Base_Type
(Etype
(N
))) = E_Subprogram_Type
2166 and then Etype
(Base_Type
(Etype
(N
))) /= Standard_Void_Type
;
2169 Get_First_Interp
(N
, I
, It
);
2170 while Present
(It
.Nam
) loop
2171 if Ekind
(Base_Type
(It
.Typ
)) /= E_Subprogram_Type
2172 or else Etype
(Base_Type
(It
.Typ
)) = Standard_Void_Type
2177 Get_Next_Interp
(I
, It
);
2182 end Is_Function_Type
;
2184 -- Start of processing for Analyze_Explicit_Dereference
2187 -- In formal verification mode, keep track of all reads and writes
2188 -- through explicit dereferences.
2190 if GNATprove_Mode
then
2191 SPARK_Specific
.Generate_Dereference
(N
);
2195 Set_Etype
(N
, Any_Type
);
2197 -- Test for remote access to subprogram type, and if so return
2198 -- after rewriting the original tree.
2200 if Remote_AST_E_Dereference
(P
) then
2204 -- Normal processing for other than remote access to subprogram type
2206 if not Is_Overloaded
(P
) then
2207 if Is_Access_Type
(Etype
(P
)) then
2212 DT
: constant Entity_Id
:= Designated_Type
(Etype
(P
));
2215 -- An explicit dereference is a legal occurrence of an
2216 -- incomplete type imported through a limited_with clause, if
2217 -- the full view is visible, or if we are within an instance
2218 -- body, where the enclosing body has a regular with_clause
2221 if From_Limited_With
(DT
)
2222 and then not From_Limited_With
(Scope
(DT
))
2224 (Is_Immediately_Visible
(Scope
(DT
))
2226 (Is_Child_Unit
(Scope
(DT
))
2227 and then Is_Visible_Lib_Unit
(Scope
(DT
)))
2228 or else In_Instance_Body
)
2230 Set_Etype
(N
, Available_View
(DT
));
2237 elsif Etype
(P
) /= Any_Type
then
2238 Error_Msg_N
("prefix of dereference must be an access type", N
);
2243 Get_First_Interp
(P
, I
, It
);
2244 while Present
(It
.Nam
) loop
2247 if Is_Access_Type
(T
) then
2248 Add_One_Interp
(N
, Designated_Type
(T
), Designated_Type
(T
));
2251 Get_Next_Interp
(I
, It
);
2254 -- Error if no interpretation of the prefix has an access type
2256 if Etype
(N
) = Any_Type
then
2258 ("access type required in prefix of explicit dereference", P
);
2259 Set_Etype
(N
, Any_Type
);
2265 and then Nkind
(Parent
(N
)) /= N_Indexed_Component
2267 and then (Nkind
(Parent
(N
)) /= N_Function_Call
2268 or else N
/= Name
(Parent
(N
)))
2270 and then (Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
2271 or else N
/= Name
(Parent
(N
)))
2273 and then Nkind
(Parent
(N
)) /= N_Subprogram_Renaming_Declaration
2274 and then (Nkind
(Parent
(N
)) /= N_Attribute_Reference
2276 (Attribute_Name
(Parent
(N
)) /= Name_Address
2278 Attribute_Name
(Parent
(N
)) /= Name_Access
))
2280 -- Name is a function call with no actuals, in a context that
2281 -- requires deproceduring (including as an actual in an enclosing
2282 -- function or procedure call). There are some pathological cases
2283 -- where the prefix might include functions that return access to
2284 -- subprograms and others that return a regular type. Disambiguation
2285 -- of those has to take place in Resolve.
2288 Make_Function_Call
(Loc
,
2289 Name
=> Make_Explicit_Dereference
(Loc
, P
),
2290 Parameter_Associations
=> New_List
);
2292 -- If the prefix is overloaded, remove operations that have formals,
2293 -- we know that this is a parameterless call.
2295 if Is_Overloaded
(P
) then
2296 Get_First_Interp
(P
, I
, It
);
2297 while Present
(It
.Nam
) loop
2300 if Is_Access_Type
(T
)
2301 and then No
(First_Formal
(Base_Type
(Designated_Type
(T
))))
2308 Get_Next_Interp
(I
, It
);
2315 elsif not Is_Function_Type
2316 and then Is_Overloaded
(N
)
2318 -- The prefix may include access to subprograms and other access
2319 -- types. If the context selects the interpretation that is a
2320 -- function call (not a procedure call) we cannot rewrite the node
2321 -- yet, but we include the result of the call interpretation.
2323 Get_First_Interp
(N
, I
, It
);
2324 while Present
(It
.Nam
) loop
2325 if Ekind
(Base_Type
(It
.Typ
)) = E_Subprogram_Type
2326 and then Etype
(Base_Type
(It
.Typ
)) /= Standard_Void_Type
2327 and then Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
2329 Add_One_Interp
(N
, Etype
(It
.Typ
), Etype
(It
.Typ
));
2332 Get_Next_Interp
(I
, It
);
2336 -- A value of remote access-to-class-wide must not be dereferenced
2339 Validate_Remote_Access_To_Class_Wide_Type
(N
);
2340 end Analyze_Explicit_Dereference
;
2342 ------------------------
2343 -- Analyze_Expression --
2344 ------------------------
2346 procedure Analyze_Expression
(N
: Node_Id
) is
2348 -- If the expression is an indexed component that will be rewritten
2349 -- as a container indexing, it has already been analyzed.
2351 if Nkind
(N
) = N_Indexed_Component
2352 and then Present
(Generalized_Indexing
(N
))
2358 Check_Parameterless_Call
(N
);
2360 end Analyze_Expression
;
2362 -------------------------------------
2363 -- Analyze_Expression_With_Actions --
2364 -------------------------------------
2366 procedure Analyze_Expression_With_Actions
(N
: Node_Id
) is
2368 procedure Check_Action_OK
(A
: Node_Id
);
2369 -- Check that the action A is allowed as a declare_item of a declare
2370 -- expression if N and A come from source.
2372 ---------------------
2373 -- Check_Action_OK --
2374 ---------------------
2376 procedure Check_Action_OK
(A
: Node_Id
) is
2378 if not Comes_From_Source
(N
) or else not Comes_From_Source
(A
) then
2380 -- If, for example, an (illegal) expression function is
2381 -- transformed into a "vanilla" function then we don't want to
2382 -- allow it just because Comes_From_Source is now False. So look
2383 -- at the Original_Node.
2385 if Is_Rewrite_Substitution
(A
) then
2386 Check_Action_OK
(Original_Node
(A
));
2389 return; -- Allow anything in generated code
2393 when N_Object_Declaration
=>
2394 if Nkind
(Object_Definition
(A
)) = N_Access_Definition
then
2396 ("anonymous access type not allowed in declare_expression",
2397 Object_Definition
(A
));
2400 if Aliased_Present
(A
) then
2401 Error_Msg_N
("ALIASED not allowed in declare_expression", A
);
2404 if Constant_Present
(A
)
2405 and then not Is_Limited_Type
(Etype
(Defining_Identifier
(A
)))
2407 return; -- nonlimited constants are OK
2410 when N_Object_Renaming_Declaration
=>
2411 if Present
(Access_Definition
(A
)) then
2413 ("anonymous access type not allowed in declare_expression",
2414 Access_Definition
(A
));
2417 if not Is_Limited_Type
(Etype
(Defining_Identifier
(A
))) then
2418 return; -- ???For now; the RM rule is a bit more complicated
2423 -- See AI22-0045 pragma categorization.
2424 subtype Executable_Pragma_Id
is Pragma_Id
2425 with Predicate
=> Executable_Pragma_Id
in
2426 -- language-defined executable pragmas
2427 Pragma_Assert | Pragma_Inspection_Point
2429 -- GNAT-defined executable pragmas
2430 | Pragma_Assume | Pragma_Debug
;
2432 if Get_Pragma_Id
(A
) in Executable_Pragma_Id
then
2438 null; -- Nothing else allowed
2441 -- We could mention pragmas in the message text; let's not.
2442 Error_Msg_N
("object renaming or constant declaration expected", A
);
2443 end Check_Action_OK
;
2446 EWA_Scop
: Entity_Id
;
2448 -- Start of processing for Analyze_Expression_With_Actions
2451 -- Create a scope, which is needed to provide proper visibility of the
2454 EWA_Scop
:= New_Internal_Entity
(E_Block
, Current_Scope
, Sloc
(N
), 'B');
2455 Set_Etype
(EWA_Scop
, Standard_Void_Type
);
2456 Set_Scope
(EWA_Scop
, Current_Scope
);
2457 Set_Parent
(EWA_Scop
, N
);
2458 Push_Scope
(EWA_Scop
);
2460 -- If this Expression_With_Actions node comes from source, then it
2461 -- represents a declare_expression; increment the counter to take note
2464 if Comes_From_Source
(N
) then
2465 In_Declare_Expr
:= In_Declare_Expr
+ 1;
2468 A
:= First
(Actions
(N
));
2469 while Present
(A
) loop
2471 Check_Action_OK
(A
);
2475 Analyze_Expression
(Expression
(N
));
2476 Set_Etype
(N
, Etype
(Expression
(N
)));
2479 if Comes_From_Source
(N
) then
2480 In_Declare_Expr
:= In_Declare_Expr
- 1;
2482 end Analyze_Expression_With_Actions
;
2484 ---------------------------
2485 -- Analyze_If_Expression --
2486 ---------------------------
2488 procedure Analyze_If_Expression
(N
: Node_Id
) is
2489 Condition
: constant Node_Id
:= First
(Expressions
(N
));
2491 Then_Expr
: Node_Id
;
2492 Else_Expr
: Node_Id
;
2494 procedure Check_Else_Expression
(T
: Entity_Id
);
2495 -- Check one interpretation of the THEN expression with type T
2497 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
);
2498 -- Check THEN expression with type T1 and ELSE expression with type T2
2500 ---------------------------
2501 -- Check_Else_Expression --
2502 ---------------------------
2504 procedure Check_Else_Expression
(T
: Entity_Id
) is
2509 -- Loop through the interpretations of the ELSE expression
2511 if not Is_Overloaded
(Else_Expr
) then
2512 Check_Expression_Pair
(T
, Etype
(Else_Expr
));
2515 Get_First_Interp
(Else_Expr
, I
, It
);
2516 while Present
(It
.Typ
) loop
2517 Check_Expression_Pair
(T
, It
.Typ
);
2518 Get_Next_Interp
(I
, It
);
2521 end Check_Else_Expression
;
2523 ---------------------------
2524 -- Check_Expression_Pair --
2525 ---------------------------
2527 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
) is
2531 if Covers
(T1
=> T1
, T2
=> T2
)
2532 or else Covers
(T1
=> T2
, T2
=> T1
)
2534 T
:= Specific_Type
(T1
, T2
);
2536 elsif Is_User_Defined_Literal
(Then_Expr
, T2
) then
2539 elsif Is_User_Defined_Literal
(Else_Expr
, T1
) then
2543 T
:= Possible_Type_For_Conditional_Expression
(T1
, T2
);
2550 Add_One_Interp
(N
, T
, T
);
2551 end Check_Expression_Pair
;
2558 -- Start of processing for Analyze_If_Expression
2561 -- Defend against error of missing expressions from previous error
2563 if No
(Condition
) then
2564 Check_Error_Detected
;
2568 Set_Etype
(N
, Any_Type
);
2570 Then_Expr
:= Next
(Condition
);
2572 if No
(Then_Expr
) then
2573 Check_Error_Detected
;
2577 Else_Expr
:= Next
(Then_Expr
);
2579 -- Analyze and resolve the condition. We need to resolve this now so
2580 -- that it gets folded to True/False if possible, before we analyze
2581 -- the THEN/ELSE branches, because when analyzing these branches, we
2582 -- may call Is_Statically_Unevaluated, which expects the condition of
2583 -- an enclosing IF to have been analyze/resolved/evaluated.
2585 Analyze_Expression
(Condition
);
2586 Resolve
(Condition
, Any_Boolean
);
2588 -- Analyze the THEN expression and (if present) the ELSE expression. For
2589 -- them we delay resolution in the normal manner because of overloading.
2591 Analyze_Expression
(Then_Expr
);
2593 if Present
(Else_Expr
) then
2594 Analyze_Expression
(Else_Expr
);
2597 -- RM 4.5.7(10/3): If the if_expression is the operand of a type
2598 -- conversion, the type of the if_expression is the target type
2599 -- of the conversion.
2601 if Nkind
(Parent
(N
)) = N_Type_Conversion
then
2602 Set_Etype
(N
, Etype
(Parent
(N
)));
2606 -- Loop through the interpretations of the THEN expression and check the
2607 -- ELSE expression if present.
2609 if not Is_Overloaded
(Then_Expr
) then
2610 if Present
(Else_Expr
) then
2611 Check_Else_Expression
(Etype
(Then_Expr
));
2613 Set_Etype
(N
, Etype
(Then_Expr
));
2617 Get_First_Interp
(Then_Expr
, I
, It
);
2618 while Present
(It
.Typ
) loop
2619 if Present
(Else_Expr
) then
2620 Check_Else_Expression
(It
.Typ
);
2622 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
2625 Get_Next_Interp
(I
, It
);
2629 -- If no possible interpretation has been found, the type of the
2630 -- ELSE expression does not match any interpretation of the THEN
2633 if Etype
(N
) = Any_Type
then
2634 if Is_Overloaded
(Then_Expr
) then
2635 if Is_Overloaded
(Else_Expr
) then
2637 ("no interpretation compatible with those of THEN expression",
2641 ("type of ELSE incompatible with interpretations of THEN "
2645 ("\ELSE expression has}!", Else_Expr
, Etype
(Else_Expr
));
2648 elsif Present
(Else_Expr
) then
2649 if Is_Overloaded
(Else_Expr
) then
2651 ("no interpretation compatible with type of THEN expression",
2654 ("\THEN expression has}!", Else_Expr
, Etype
(Then_Expr
));
2657 ("type of ELSE incompatible with that of THEN expression",
2660 ("\THEN expression has}!", Else_Expr
, Etype
(Then_Expr
));
2662 ("\ELSE expression has}!", Else_Expr
, Etype
(Else_Expr
));
2666 end Analyze_If_Expression
;
2668 ------------------------------------
2669 -- Analyze_Indexed_Component_Form --
2670 ------------------------------------
2672 procedure Analyze_Indexed_Component_Form
(N
: Node_Id
) is
2673 P
: constant Node_Id
:= Prefix
(N
);
2674 Exprs
: constant List_Id
:= Expressions
(N
);
2680 procedure Process_Function_Call
;
2681 -- Prefix in indexed component form is an overloadable entity, so the
2682 -- node is very likely a function call; reformat it as such. The only
2683 -- exception is a call to a parameterless function that returns an
2684 -- array type, or an access type thereof, in which case this will be
2685 -- undone later by Resolve_Call or Resolve_Entry_Call.
2687 procedure Process_Indexed_Component
;
2688 -- Prefix in indexed component form is actually an indexed component.
2689 -- This routine processes it, knowing that the prefix is already
2692 procedure Process_Indexed_Component_Or_Slice
;
2693 -- An indexed component with a single index may designate a slice if
2694 -- the index is a subtype mark. This routine disambiguates these two
2695 -- cases by resolving the prefix to see if it is a subtype mark.
2697 procedure Process_Overloaded_Indexed_Component
;
2698 -- If the prefix of an indexed component is overloaded, the proper
2699 -- interpretation is selected by the index types and the context.
2701 ---------------------------
2702 -- Process_Function_Call --
2703 ---------------------------
2705 procedure Process_Function_Call
is
2706 Loc
: constant Source_Ptr
:= Sloc
(N
);
2710 Change_Node
(N
, N_Function_Call
);
2712 Set_Parameter_Associations
(N
, Exprs
);
2714 -- Analyze actuals prior to analyzing the call itself
2716 Actual
:= First
(Parameter_Associations
(N
));
2717 while Present
(Actual
) loop
2719 Check_Parameterless_Call
(Actual
);
2721 -- Move to next actual. Note that we use Next, not Next_Actual
2722 -- here. The reason for this is a bit subtle. If a function call
2723 -- includes named associations, the parser recognizes the node
2724 -- as a call, and it is analyzed as such. If all associations are
2725 -- positional, the parser builds an indexed_component node, and
2726 -- it is only after analysis of the prefix that the construct
2727 -- is recognized as a call, in which case Process_Function_Call
2728 -- rewrites the node and analyzes the actuals. If the list of
2729 -- actuals is malformed, the parser may leave the node as an
2730 -- indexed component (despite the presence of named associations).
2731 -- The iterator Next_Actual is equivalent to Next if the list is
2732 -- positional, but follows the normalized chain of actuals when
2733 -- named associations are present. In this case normalization has
2734 -- not taken place, and actuals remain unanalyzed, which leads to
2735 -- subsequent crashes or loops if there is an attempt to continue
2736 -- analysis of the program.
2738 -- IF there is a single actual and it is a type name, the node
2739 -- can only be interpreted as a slice of a parameterless call.
2740 -- Rebuild the node as such and analyze.
2742 if No
(Next
(Actual
))
2743 and then Is_Entity_Name
(Actual
)
2744 and then Is_Type
(Entity
(Actual
))
2745 and then Is_Discrete_Type
(Entity
(Actual
))
2746 and then not Is_Current_Instance
(Actual
)
2752 New_Occurrence_Of
(Entity
(Actual
), Loc
)));
2762 end Process_Function_Call
;
2764 -------------------------------
2765 -- Process_Indexed_Component --
2766 -------------------------------
2768 procedure Process_Indexed_Component
is
2770 Array_Type
: Entity_Id
;
2772 Pent
: Entity_Id
:= Empty
;
2775 Exp
:= First
(Exprs
);
2777 if Is_Overloaded
(P
) then
2778 Process_Overloaded_Indexed_Component
;
2781 Array_Type
:= Etype
(P
);
2783 if Is_Entity_Name
(P
) then
2785 elsif Nkind
(P
) = N_Selected_Component
2786 and then Is_Entity_Name
(Selector_Name
(P
))
2788 Pent
:= Entity
(Selector_Name
(P
));
2791 -- Prefix must be appropriate for an array type, taking into
2792 -- account a possible implicit dereference.
2794 if Is_Access_Type
(Array_Type
) then
2796 (Warn_On_Dereference
, "?d?implicit dereference", N
);
2797 Array_Type
:= Implicitly_Designated_Type
(Array_Type
);
2800 if Is_Array_Type
(Array_Type
) then
2802 -- In order to correctly access First_Index component later,
2803 -- replace string literal subtype by its parent type.
2805 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
2806 Array_Type
:= Etype
(Array_Type
);
2809 elsif Present
(Pent
) and then Ekind
(Pent
) = E_Entry_Family
then
2811 Set_Etype
(N
, Any_Type
);
2813 if not Has_Compatible_Type
(Exp
, Entry_Index_Type
(Pent
)) then
2814 Error_Msg_N
("invalid index type in entry name", N
);
2816 elsif Present
(Next
(Exp
)) then
2817 Error_Msg_N
("too many subscripts in entry reference", N
);
2820 Set_Etype
(N
, Etype
(P
));
2825 elsif Is_Record_Type
(Array_Type
)
2826 and then Remote_AST_I_Dereference
(P
)
2830 elsif Try_Container_Indexing
(N
, P
, Exprs
) then
2833 elsif Array_Type
= Any_Type
then
2834 Set_Etype
(N
, Any_Type
);
2836 -- In most cases the analysis of the prefix will have emitted
2837 -- an error already, but if the prefix may be interpreted as a
2838 -- call in prefixed notation, the report is left to the caller.
2839 -- To prevent cascaded errors, report only if no previous ones.
2841 if Serious_Errors_Detected
= 0 then
2842 Error_Msg_N
("invalid prefix in indexed component", P
);
2844 if Nkind
(P
) = N_Expanded_Name
then
2845 Error_Msg_NE
("\& is not visible", P
, Selector_Name
(P
));
2851 -- Here we definitely have a bad indexing
2854 if Nkind
(Parent
(N
)) = N_Requeue_Statement
2855 and then Present
(Pent
) and then Ekind
(Pent
) = E_Entry
2858 ("REQUEUE does not permit parameters", First
(Exprs
));
2860 elsif Is_Entity_Name
(P
)
2861 and then Etype
(P
) = Standard_Void_Type
2863 Error_Msg_NE
("incorrect use of &", P
, Entity
(P
));
2866 Error_Msg_N
("array type required in indexed component", P
);
2869 Set_Etype
(N
, Any_Type
);
2873 Index
:= First_Index
(Array_Type
);
2874 while Present
(Index
) and then Present
(Exp
) loop
2875 if not Has_Compatible_Type
(Exp
, Etype
(Index
)) then
2876 Wrong_Type
(Exp
, Etype
(Index
));
2877 Set_Etype
(N
, Any_Type
);
2885 Set_Etype
(N
, Component_Type
(Array_Type
));
2886 Check_Implicit_Dereference
(N
, Etype
(N
));
2888 if Present
(Index
) then
2890 ("too few subscripts in array reference", First
(Exprs
));
2892 elsif Present
(Exp
) then
2893 Error_Msg_N
("too many subscripts in array reference", Exp
);
2896 end Process_Indexed_Component
;
2898 ----------------------------------------
2899 -- Process_Indexed_Component_Or_Slice --
2900 ----------------------------------------
2902 procedure Process_Indexed_Component_Or_Slice
is
2904 Exp
:= First
(Exprs
);
2905 while Present
(Exp
) loop
2906 Analyze_Expression
(Exp
);
2910 Exp
:= First
(Exprs
);
2912 -- If one index is present, and it is a subtype name, then the node
2913 -- denotes a slice (note that the case of an explicit range for a
2914 -- slice was already built as an N_Slice node in the first place,
2915 -- so that case is not handled here).
2917 -- We use a replace rather than a rewrite here because this is one
2918 -- of the cases in which the tree built by the parser is plain wrong.
2921 and then Is_Entity_Name
(Exp
)
2922 and then Is_Type
(Entity
(Exp
))
2925 Make_Slice
(Sloc
(N
),
2927 Discrete_Range
=> New_Copy
(Exp
)));
2930 -- Otherwise (more than one index present, or single index is not
2931 -- a subtype name), then we have the indexed component case.
2934 Process_Indexed_Component
;
2936 end Process_Indexed_Component_Or_Slice
;
2938 ------------------------------------------
2939 -- Process_Overloaded_Indexed_Component --
2940 ------------------------------------------
2942 procedure Process_Overloaded_Indexed_Component
is
2951 Set_Etype
(N
, Any_Type
);
2953 Get_First_Interp
(P
, I
, It
);
2954 while Present
(It
.Nam
) loop
2957 if Is_Access_Type
(Typ
) then
2958 Typ
:= Designated_Type
(Typ
);
2960 (Warn_On_Dereference
, "?d?implicit dereference", N
);
2963 if Is_Array_Type
(Typ
) then
2965 -- Got a candidate: verify that index types are compatible
2967 Index
:= First_Index
(Typ
);
2969 Exp
:= First
(Exprs
);
2970 while Present
(Index
) and then Present
(Exp
) loop
2971 if Has_Compatible_Type
(Exp
, Etype
(Index
)) then
2983 if Found
and then No
(Index
) and then No
(Exp
) then
2985 CT
: constant Entity_Id
:=
2986 Base_Type
(Component_Type
(Typ
));
2988 Add_One_Interp
(N
, CT
, CT
);
2989 Check_Implicit_Dereference
(N
, CT
);
2993 elsif Try_Container_Indexing
(N
, P
, Exprs
) then
2998 Get_Next_Interp
(I
, It
);
3001 if Etype
(N
) = Any_Type
then
3002 Error_Msg_N
("no legal interpretation for indexed component", N
);
3003 Set_Is_Overloaded
(N
, False);
3005 end Process_Overloaded_Indexed_Component
;
3007 -- Start of processing for Analyze_Indexed_Component_Form
3010 -- Get name of array, function or type
3014 -- If P is an explicit dereference whose prefix is of a remote access-
3015 -- to-subprogram type, then N has already been rewritten as a subprogram
3016 -- call and analyzed.
3018 if Nkind
(N
) in N_Subprogram_Call
then
3021 -- When the prefix is attribute 'Loop_Entry and the sole expression of
3022 -- the indexed component denotes a loop name, the indexed form is turned
3023 -- into an attribute reference.
3025 elsif Nkind
(N
) = N_Attribute_Reference
3026 and then Attribute_Name
(N
) = Name_Loop_Entry
3031 pragma Assert
(Nkind
(N
) = N_Indexed_Component
);
3033 P_T
:= Base_Type
(Etype
(P
));
3035 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
3038 if Is_Type
(U_N
) then
3040 -- Reformat node as a type conversion
3042 E
:= Remove_Head
(Exprs
);
3044 if Present
(First
(Exprs
)) then
3046 ("argument of type conversion must be single expression", N
);
3049 Change_Node
(N
, N_Type_Conversion
);
3050 Set_Subtype_Mark
(N
, P
);
3052 Set_Expression
(N
, E
);
3054 -- After changing the node, call for the specific Analysis
3055 -- routine directly, to avoid a double call to the expander.
3057 Analyze_Type_Conversion
(N
);
3061 if Is_Overloadable
(U_N
) then
3062 Process_Function_Call
;
3064 elsif Ekind
(Etype
(P
)) = E_Subprogram_Type
3065 or else (Is_Access_Type
(Etype
(P
))
3067 Ekind
(Designated_Type
(Etype
(P
))) =
3070 -- Call to access_to-subprogram with possible implicit dereference
3072 Process_Function_Call
;
3074 elsif Is_Generic_Subprogram
(U_N
) then
3076 -- A common beginner's (or C++ templates fan) error
3078 Error_Msg_N
("generic subprogram cannot be called", N
);
3079 Set_Etype
(N
, Any_Type
);
3083 Process_Indexed_Component_Or_Slice
;
3086 -- If not an entity name, prefix is an expression that may denote
3087 -- an array or an access-to-subprogram.
3090 if Ekind
(P_T
) = E_Subprogram_Type
3091 or else (Is_Access_Type
(P_T
)
3093 Ekind
(Designated_Type
(P_T
)) = E_Subprogram_Type
)
3095 Process_Function_Call
;
3097 elsif Nkind
(P
) = N_Selected_Component
3098 and then Present
(Entity
(Selector_Name
(P
)))
3099 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
3101 Process_Function_Call
;
3103 -- Indexed component, slice, or a call to a member of a family
3104 -- entry, which will be converted to an entry call later.
3106 Process_Indexed_Component_Or_Slice
;
3110 Analyze_Dimension
(N
);
3111 end Analyze_Indexed_Component_Form
;
3113 ------------------------
3114 -- Analyze_Logical_Op --
3115 ------------------------
3117 procedure Analyze_Logical_Op
(N
: Node_Id
) is
3118 L
: constant Node_Id
:= Left_Opnd
(N
);
3119 R
: constant Node_Id
:= Right_Opnd
(N
);
3124 Set_Etype
(N
, Any_Type
);
3125 Candidate_Type
:= Empty
;
3127 Analyze_Expression
(L
);
3128 Analyze_Expression
(R
);
3130 -- If the entity is already set, the node is the instantiation of a
3131 -- generic node with a non-local reference, or was manufactured by a
3132 -- call to Make_Op_xxx. In either case the entity is known to be valid,
3133 -- and we do not need to collect interpretations, instead we just get
3134 -- the single possible interpretation.
3136 if Present
(Entity
(N
)) then
3137 Op_Id
:= Entity
(N
);
3139 if Ekind
(Op_Id
) = E_Operator
then
3140 Find_Boolean_Types
(L
, R
, Op_Id
, N
);
3142 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
3145 -- Entity is not already set, so we do need to collect interpretations
3148 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
3149 while Present
(Op_Id
) loop
3150 if Ekind
(Op_Id
) = E_Operator
then
3151 Find_Boolean_Types
(L
, R
, Op_Id
, N
);
3153 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
3156 Op_Id
:= Homonym
(Op_Id
);
3161 Check_Function_Writable_Actuals
(N
);
3164 if Nkind
(L
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
3165 and then Is_Boolean_Type
(Etype
(L
))
3167 Check_Xtra_Parens_Precedence
(L
);
3170 if Nkind
(R
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
3171 and then Is_Boolean_Type
(Etype
(R
))
3173 Check_Xtra_Parens_Precedence
(R
);
3176 end Analyze_Logical_Op
;
3178 ---------------------------
3179 -- Analyze_Membership_Op --
3180 ---------------------------
3182 procedure Analyze_Membership_Op
(N
: Node_Id
) is
3183 Loc
: constant Source_Ptr
:= Sloc
(N
);
3184 L
: constant Node_Id
:= Left_Opnd
(N
);
3185 R
: constant Node_Id
:= Right_Opnd
(N
);
3187 procedure Analyze_Set_Membership
;
3188 -- If a set of alternatives is present, analyze each and find the
3189 -- common type to which they must all resolve.
3191 function Find_Interp
return Boolean;
3192 -- Find a valid interpretation of the test. Note that the context of the
3193 -- operation plays no role in resolving the operands, so that if there
3194 -- is more than one interpretation of the operands that is compatible
3195 -- with the test, the operation is ambiguous.
3197 function Try_Left_Interp
(T
: Entity_Id
) return Boolean;
3198 -- Try an interpretation of the left operand with type T. Return true if
3199 -- one interpretation (at least) of the right operand making up a valid
3200 -- operand pair exists, otherwise false if no such pair exists.
3202 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean;
3203 -- Return true if T1 and T2 constitute a valid pair of operand types for
3204 -- L and R respectively.
3206 ----------------------------
3207 -- Analyze_Set_Membership --
3208 ----------------------------
3210 procedure Analyze_Set_Membership
is
3212 Index
: Interp_Index
;
3214 Candidate_Interps
: Node_Id
;
3215 Common_Type
: Entity_Id
:= Empty
;
3219 Candidate_Interps
:= L
;
3221 if not Is_Overloaded
(L
) then
3222 Common_Type
:= Etype
(L
);
3224 Alt
:= First
(Alternatives
(N
));
3225 while Present
(Alt
) loop
3228 if not Has_Compatible_Type
(Alt
, Common_Type
) then
3229 Wrong_Type
(Alt
, Common_Type
);
3236 Alt
:= First
(Alternatives
(N
));
3237 while Present
(Alt
) loop
3239 if not Is_Overloaded
(Alt
) then
3240 Common_Type
:= Etype
(Alt
);
3243 Get_First_Interp
(Alt
, Index
, It
);
3244 while Present
(It
.Typ
) loop
3246 Has_Compatible_Type
(Candidate_Interps
, It
.Typ
)
3248 Remove_Interp
(Index
);
3251 Get_Next_Interp
(Index
, It
);
3254 Get_First_Interp
(Alt
, Index
, It
);
3257 Error_Msg_N
("alternative has no legal type", Alt
);
3261 -- If alternative is not overloaded, we have a unique type
3264 Set_Etype
(Alt
, It
.Typ
);
3266 -- If the alternative is an enumeration literal, use the one
3267 -- for this interpretation.
3269 if Is_Entity_Name
(Alt
) then
3270 Set_Entity
(Alt
, It
.Nam
);
3273 Get_Next_Interp
(Index
, It
);
3276 Set_Is_Overloaded
(Alt
, False);
3277 Common_Type
:= Etype
(Alt
);
3280 Candidate_Interps
:= Alt
;
3287 if Present
(Common_Type
) then
3288 Set_Etype
(L
, Common_Type
);
3290 -- The left operand may still be overloaded, to be resolved using
3294 Error_Msg_N
("cannot resolve membership operation", N
);
3296 end Analyze_Set_Membership
;
3302 function Find_Interp
return Boolean is
3307 Valid_I
: Interp_Index
;
3310 -- Loop through the interpretations of the left operand
3312 if not Is_Overloaded
(L
) then
3313 Found
:= Try_Left_Interp
(Etype
(L
));
3320 Get_First_Interp
(L
, I
, It
);
3321 while Present
(It
.Typ
) loop
3322 if Try_Left_Interp
(It
.Typ
) then
3323 -- If several interpretations are possible, disambiguate
3326 and then Base_Type
(It
.Typ
) /= Base_Type
(L_Typ
)
3328 It
:= Disambiguate
(L
, Valid_I
, I
, Any_Type
);
3330 if It
= No_Interp
then
3331 Ambiguous_Operands
(N
);
3332 Set_Etype
(L
, Any_Type
);
3341 Set_Etype
(L
, L_Typ
);
3345 Get_Next_Interp
(I
, It
);
3352 ---------------------
3353 -- Try_Left_Interp --
3354 ---------------------
3356 function Try_Left_Interp
(T
: Entity_Id
) return Boolean is
3361 Valid_I
: Interp_Index
;
3364 -- Defend against previous error
3366 if Nkind
(R
) = N_Error
then
3369 -- Loop through the interpretations of the right operand
3371 elsif not Is_Overloaded
(R
) then
3372 Found
:= Is_Valid_Pair
(T
, Etype
(R
));
3379 Get_First_Interp
(R
, I
, It
);
3380 while Present
(It
.Typ
) loop
3381 if Is_Valid_Pair
(T
, It
.Typ
) then
3382 -- If several interpretations are possible, disambiguate
3385 and then Base_Type
(It
.Typ
) /= Base_Type
(R_Typ
)
3387 It
:= Disambiguate
(R
, Valid_I
, I
, Any_Type
);
3389 if It
= No_Interp
then
3390 Ambiguous_Operands
(N
);
3391 Set_Etype
(R
, Any_Type
);
3403 Get_Next_Interp
(I
, It
);
3408 end Try_Left_Interp
;
3414 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean is
3416 return Covers
(T1
=> T1
, T2
=> T2
)
3417 or else Covers
(T1
=> T2
, T2
=> T1
)
3418 or else Is_User_Defined_Literal
(L
, T2
)
3419 or else Is_User_Defined_Literal
(R
, T1
);
3427 -- Start of processing for Analyze_Membership_Op
3430 Analyze_Expression
(L
);
3433 pragma Assert
(Ada_Version
>= Ada_2012
);
3435 Analyze_Set_Membership
;
3440 Alt
:= First
(Alternatives
(N
));
3441 while Present
(Alt
) loop
3442 if Is_Entity_Name
(Alt
) and then Is_Type
(Entity
(Alt
)) then
3443 Check_Fully_Declared
(Entity
(Alt
), Alt
);
3445 if Has_Ghost_Predicate_Aspect
(Entity
(Alt
)) then
3447 ("subtype& has ghost predicate, "
3448 & "not allowed in membership test",
3457 elsif Nkind
(R
) = N_Range
3458 or else (Nkind
(R
) = N_Attribute_Reference
3459 and then Attribute_Name
(R
) = Name_Range
)
3461 Analyze_Expression
(R
);
3463 Dummy
:= Find_Interp
;
3465 -- If not a range, it can be a subtype mark, or else it is a degenerate
3466 -- membership test with a singleton value, i.e. a test for equality,
3467 -- if the types are compatible.
3470 Analyze_Expression
(R
);
3472 if Is_Entity_Name
(R
) and then Is_Type
(Entity
(R
)) then
3474 Check_Fully_Declared
(Entity
(R
), R
);
3476 if Has_Ghost_Predicate_Aspect
(Entity
(R
)) then
3478 ("subtype& has ghost predicate, "
3479 & "not allowed in membership test",
3483 elsif Ada_Version
>= Ada_2012
and then Find_Interp
then
3484 Op
:= Make_Op_Eq
(Loc
, Left_Opnd
=> L
, Right_Opnd
=> R
);
3485 Resolve_Membership_Equality
(Op
, Etype
(L
));
3487 if Nkind
(N
) = N_Not_In
then
3488 Op
:= Make_Op_Not
(Loc
, Op
);
3496 -- In all versions of the language, if we reach this point there
3497 -- is a previous error that will be diagnosed below.
3503 -- Compatibility between expression and subtype mark or range is
3504 -- checked during resolution. The result of the operation is Boolean
3507 Set_Etype
(N
, Standard_Boolean
);
3509 if Comes_From_Source
(N
)
3510 and then Present
(Right_Opnd
(N
))
3511 and then Is_CPP_Class
(Etype
(Etype
(Right_Opnd
(N
))))
3513 Error_Msg_N
("membership test not applicable to cpp-class types", N
);
3516 Check_Function_Writable_Actuals
(N
);
3517 end Analyze_Membership_Op
;
3523 procedure Analyze_Mod
(N
: Node_Id
) is
3525 -- A special warning check, if we have an expression of the form:
3526 -- expr mod 2 * literal
3527 -- where literal is 128 or less, then probably what was meant was
3528 -- expr mod 2 ** literal
3529 -- so issue an appropriate warning.
3531 if Warn_On_Suspicious_Modulus_Value
3532 and then Nkind
(Right_Opnd
(N
)) = N_Integer_Literal
3533 and then Intval
(Right_Opnd
(N
)) = Uint_2
3534 and then Nkind
(Parent
(N
)) = N_Op_Multiply
3535 and then Nkind
(Right_Opnd
(Parent
(N
))) = N_Integer_Literal
3536 and then Intval
(Right_Opnd
(Parent
(N
))) <= Uint_128
3539 ("suspicious MOD value, was '*'* intended'??.m?", Parent
(N
));
3542 -- Remaining processing is same as for other arithmetic operators
3544 Analyze_Arithmetic_Op
(N
);
3547 ----------------------
3548 -- Analyze_Negation --
3549 ----------------------
3551 procedure Analyze_Negation
(N
: Node_Id
) is
3552 R
: constant Node_Id
:= Right_Opnd
(N
);
3557 Set_Etype
(N
, Any_Type
);
3558 Candidate_Type
:= Empty
;
3560 Analyze_Expression
(R
);
3562 -- If the entity is already set, the node is the instantiation of a
3563 -- generic node with a non-local reference, or was manufactured by a
3564 -- call to Make_Op_xxx. In either case the entity is known to be valid,
3565 -- and we do not need to collect interpretations, instead we just get
3566 -- the single possible interpretation.
3568 if Present
(Entity
(N
)) then
3569 Op_Id
:= Entity
(N
);
3571 if Ekind
(Op_Id
) = E_Operator
then
3572 Find_Negation_Types
(R
, Op_Id
, N
);
3574 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
3578 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
3579 while Present
(Op_Id
) loop
3580 if Ekind
(Op_Id
) = E_Operator
then
3581 Find_Negation_Types
(R
, Op_Id
, N
);
3583 Analyze_User_Defined_Unary_Op
(N
, Op_Id
);
3586 Op_Id
:= Homonym
(Op_Id
);
3591 end Analyze_Negation
;
3597 procedure Analyze_Null
(N
: Node_Id
) is
3599 Set_Etype
(N
, Universal_Access
);
3602 ----------------------
3603 -- Analyze_One_Call --
3604 ----------------------
3606 procedure Analyze_One_Call
3610 Success
: out Boolean;
3611 Skip_First
: Boolean := False)
3613 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
3614 Prev_T
: constant Entity_Id
:= Etype
(N
);
3616 -- Recognize cases of prefixed calls that have been rewritten in
3617 -- various ways. The simplest case is a rewritten selected component,
3618 -- but it can also be an already-examined indexed component, or a
3619 -- prefix that is itself a rewritten prefixed call that is in turn
3620 -- an indexed call (the syntactic ambiguity involving the indexing of
3621 -- a function with defaulted parameters that returns an array).
3622 -- A flag Maybe_Indexed_Call might be useful here ???
3624 Must_Skip
: constant Boolean := Skip_First
3625 or else Nkind
(Original_Node
(N
)) = N_Selected_Component
3627 (Nkind
(Original_Node
(N
)) = N_Indexed_Component
3628 and then Nkind
(Prefix
(Original_Node
(N
))) =
3629 N_Selected_Component
)
3631 (Nkind
(Parent
(N
)) = N_Function_Call
3632 and then Is_Array_Type
(Etype
(Name
(N
)))
3633 and then Etype
(Original_Node
(N
)) =
3634 Component_Type
(Etype
(Name
(N
)))
3635 and then Nkind
(Original_Node
(Parent
(N
))) =
3636 N_Selected_Component
);
3638 -- The first formal must be omitted from the match when trying to find
3639 -- a primitive operation that is a possible interpretation, and also
3640 -- after the call has been rewritten, because the corresponding actual
3641 -- is already known to be compatible, and because this may be an
3642 -- indexing of a call with default parameters.
3644 First_Form
: Entity_Id
;
3647 Is_Indexed
: Boolean := False;
3648 Is_Indirect
: Boolean := False;
3649 Subp_Type
: constant Entity_Id
:= Etype
(Nam
);
3652 function Compatible_Types_In_Predicate
3654 T2
: Entity_Id
) return Boolean;
3655 -- For an Ada 2012 predicate or invariant, a call may mention an
3656 -- incomplete type, while resolution of the corresponding predicate
3657 -- function may see the full view, as a consequence of the delayed
3658 -- resolution of the corresponding expressions. This may occur in
3659 -- the body of a predicate function, or in a call to such. Anomalies
3660 -- involving private and full views can also happen. In each case,
3661 -- rewrite node or add conversions to remove spurious type errors.
3663 procedure Indicate_Name_And_Type
;
3664 -- If candidate interpretation matches, indicate name and type of result
3667 function Operator_Hidden_By
(Fun
: Entity_Id
) return Boolean;
3668 -- There may be a user-defined operator that hides the current
3669 -- interpretation. We must check for this independently of the
3670 -- analysis of the call with the user-defined operation, because
3671 -- the parameter names may be wrong and yet the hiding takes place.
3672 -- This fixes a problem with ACATS test B34014O.
3674 -- When the type Address is a visible integer type, and the DEC
3675 -- system extension is visible, the predefined operator may be
3676 -- hidden as well, by one of the address operations in auxdec.
3677 -- Finally, the abstract operations on address do not hide the
3678 -- predefined operator (this is the purpose of making them abstract).
3680 -----------------------------------
3681 -- Compatible_Types_In_Predicate --
3682 -----------------------------------
3684 function Compatible_Types_In_Predicate
3686 T2
: Entity_Id
) return Boolean
3688 function Common_Type
(T
: Entity_Id
) return Entity_Id
;
3689 -- Find non-private underlying full view if any, without going to
3690 -- ancestor type (as opposed to Underlying_Type).
3696 function Common_Type
(T
: Entity_Id
) return Entity_Id
is
3702 if Is_Private_Type
(CT
) and then Present
(Full_View
(CT
)) then
3703 CT
:= Full_View
(CT
);
3706 if Is_Private_Type
(CT
)
3707 and then Present
(Underlying_Full_View
(CT
))
3709 CT
:= Underlying_Full_View
(CT
);
3712 return Base_Type
(CT
);
3715 -- Start of processing for Compatible_Types_In_Predicate
3718 if (Ekind
(Current_Scope
) = E_Function
3719 and then Is_Predicate_Function
(Current_Scope
))
3721 (Ekind
(Nam
) = E_Function
3722 and then Is_Predicate_Function
(Nam
))
3724 if Is_Incomplete_Type
(T1
)
3725 and then Present
(Full_View
(T1
))
3726 and then Full_View
(T1
) = T2
3728 Set_Etype
(Formal
, Etype
(Actual
));
3731 elsif Common_Type
(T1
) = Common_Type
(T2
) then
3732 Rewrite
(Actual
, Unchecked_Convert_To
(Etype
(Formal
), Actual
));
3742 end Compatible_Types_In_Predicate
;
3744 ----------------------------
3745 -- Indicate_Name_And_Type --
3746 ----------------------------
3748 procedure Indicate_Name_And_Type
is
3750 Add_One_Interp
(N
, Nam
, Etype
(Nam
));
3751 Check_Implicit_Dereference
(N
, Etype
(Nam
));
3754 -- If the prefix of the call is a name, indicate the entity
3755 -- being called. If it is not a name, it is an expression that
3756 -- denotes an access to subprogram or else an entry or family. In
3757 -- the latter case, the name is a selected component, and the entity
3758 -- being called is noted on the selector.
3760 if not Is_Type
(Nam
) then
3761 if Is_Entity_Name
(Name
(N
)) then
3762 Set_Entity
(Name
(N
), Nam
);
3763 Set_Etype
(Name
(N
), Etype
(Nam
));
3765 elsif Nkind
(Name
(N
)) = N_Selected_Component
then
3766 Set_Entity
(Selector_Name
(Name
(N
)), Nam
);
3770 if Debug_Flag_E
and not Report
then
3771 Write_Str
(" Overloaded call ");
3772 Write_Int
(Int
(N
));
3773 Write_Str
(" compatible with ");
3774 Write_Int
(Int
(Nam
));
3777 end Indicate_Name_And_Type
;
3779 ------------------------
3780 -- Operator_Hidden_By --
3781 ------------------------
3783 function Operator_Hidden_By
(Fun
: Entity_Id
) return Boolean is
3784 Act1
: constant Node_Id
:= First_Actual
(N
);
3785 Act2
: constant Node_Id
:= Next_Actual
(Act1
);
3786 Form1
: constant Entity_Id
:= First_Formal
(Fun
);
3787 Form2
: constant Entity_Id
:= Next_Formal
(Form1
);
3790 if Ekind
(Fun
) /= E_Function
or else Is_Abstract_Subprogram
(Fun
) then
3793 elsif not Has_Compatible_Type
(Act1
, Etype
(Form1
)) then
3796 elsif Present
(Form2
) then
3798 or else not Has_Compatible_Type
(Act2
, Etype
(Form2
))
3803 elsif Present
(Act2
) then
3807 -- Now we know that the arity of the operator matches the function,
3808 -- and the function call is a valid interpretation. The function
3809 -- hides the operator if it has the right signature, or if one of
3810 -- its operands is a non-abstract operation on Address when this is
3811 -- a visible integer type.
3813 return Hides_Op
(Fun
, Nam
)
3814 or else Is_Descendant_Of_Address
(Etype
(Form1
))
3817 and then Is_Descendant_Of_Address
(Etype
(Form2
)));
3818 end Operator_Hidden_By
;
3820 -- Start of processing for Analyze_One_Call
3825 -- If the subprogram has no formals or if all the formals have defaults,
3826 -- and the return type is an array type, the node may denote an indexing
3827 -- of the result of a parameterless call. In Ada 2005, the subprogram
3828 -- may have one non-defaulted formal, and the call may have been written
3829 -- in prefix notation, so that the rebuilt parameter list has more than
3832 if not Is_Overloadable
(Nam
)
3833 and then Ekind
(Nam
) /= E_Subprogram_Type
3834 and then Ekind
(Nam
) /= E_Entry_Family
3839 -- An indexing requires at least one actual. The name of the call cannot
3840 -- be an implicit indirect call, so it cannot be a generated explicit
3843 if not Is_Empty_List
(Actuals
)
3845 (Needs_No_Actuals
(Nam
)
3847 (Needs_One_Actual
(Nam
)
3848 and then Present
(Next_Actual
(First
(Actuals
)))))
3850 if Is_Array_Type
(Subp_Type
)
3852 (Nkind
(Name
(N
)) /= N_Explicit_Dereference
3853 or else Comes_From_Source
(Name
(N
)))
3855 Is_Indexed
:= Try_Indexed_Call
(N
, Nam
, Subp_Type
, Must_Skip
);
3857 elsif Is_Access_Type
(Subp_Type
)
3858 and then Is_Array_Type
(Designated_Type
(Subp_Type
))
3862 (N
, Nam
, Designated_Type
(Subp_Type
), Must_Skip
);
3864 -- The prefix can also be a parameterless function that returns an
3865 -- access to subprogram, in which case this is an indirect call.
3866 -- If this succeeds, an explicit dereference is added later on,
3867 -- in Analyze_Call or Resolve_Call.
3869 elsif Is_Access_Type
(Subp_Type
)
3870 and then Ekind
(Designated_Type
(Subp_Type
)) = E_Subprogram_Type
3872 Is_Indirect
:= Try_Indirect_Call
(N
, Nam
, Subp_Type
);
3877 -- If the call has been transformed into a slice, it is of the form
3878 -- F (Subtype) where F is parameterless. The node has been rewritten in
3879 -- Try_Indexed_Call and there is nothing else to do.
3882 and then Nkind
(N
) = N_Slice
3888 (N
, Nam
, (Report
and not Is_Indexed
and not Is_Indirect
), Norm_OK
);
3892 -- If an indirect call is a possible interpretation, indicate
3893 -- success to the caller. This may be an indexing of an explicit
3894 -- dereference of a call that returns an access type (see above).
3898 and then Nkind
(Name
(N
)) = N_Explicit_Dereference
3899 and then Comes_From_Source
(Name
(N
)))
3904 -- Mismatch in number or names of parameters
3906 elsif Debug_Flag_E
then
3907 Write_Str
(" normalization fails in call ");
3908 Write_Int
(Int
(N
));
3909 Write_Str
(" with subprogram ");
3910 Write_Int
(Int
(Nam
));
3914 -- If the context expects a function call, discard any interpretation
3915 -- that is a procedure. If the node is not overloaded, leave as is for
3916 -- better error reporting when type mismatch is found.
3918 elsif Nkind
(N
) = N_Function_Call
3919 and then Is_Overloaded
(Name
(N
))
3920 and then Ekind
(Nam
) = E_Procedure
3924 -- Ditto for function calls in a procedure context
3926 elsif Nkind
(N
) = N_Procedure_Call_Statement
3927 and then Is_Overloaded
(Name
(N
))
3928 and then Etype
(Nam
) /= Standard_Void_Type
3932 elsif No
(Actuals
) then
3934 -- If Normalize succeeds, then there are default parameters for
3937 Indicate_Name_And_Type
;
3939 elsif Ekind
(Nam
) = E_Operator
then
3940 if Nkind
(N
) = N_Procedure_Call_Statement
then
3944 -- This occurs when the prefix of the call is an operator name
3945 -- or an expanded name whose selector is an operator name.
3947 Analyze_Operator_Call
(N
, Nam
);
3949 if Etype
(N
) /= Prev_T
then
3951 -- Check that operator is not hidden by a function interpretation
3953 if Is_Overloaded
(Name
(N
)) then
3959 Get_First_Interp
(Name
(N
), I
, It
);
3960 while Present
(It
.Nam
) loop
3961 if Operator_Hidden_By
(It
.Nam
) then
3962 Set_Etype
(N
, Prev_T
);
3966 Get_Next_Interp
(I
, It
);
3971 -- If operator matches formals, record its name on the call.
3972 -- If the operator is overloaded, Resolve will select the
3973 -- correct one from the list of interpretations. The call
3974 -- node itself carries the first candidate.
3976 Set_Entity
(Name
(N
), Nam
);
3979 elsif Report
and then Etype
(N
) = Any_Type
then
3980 Error_Msg_N
("incompatible arguments for operator", N
);
3984 -- Normalize_Actuals has chained the named associations in the
3985 -- correct order of the formals.
3987 Actual
:= First_Actual
(N
);
3988 Formal
:= First_Formal
(Nam
);
3989 First_Form
:= Formal
;
3991 -- If we are analyzing a call rewritten from object notation, skip
3992 -- first actual, which may be rewritten later as an explicit
3996 Next_Actual
(Actual
);
3997 Next_Formal
(Formal
);
4000 while Present
(Actual
) and then Present
(Formal
) loop
4001 if Nkind
(Parent
(Actual
)) /= N_Parameter_Association
4002 or else Chars
(Selector_Name
(Parent
(Actual
))) = Chars
(Formal
)
4004 -- The actual can be compatible with the formal, but we must
4005 -- also check that the context is not an address type that is
4006 -- visibly an integer type. In this case the use of literals is
4007 -- illegal, except in the body of descendants of system, where
4008 -- arithmetic operations on address are of course used.
4010 if Has_Compatible_Type
(Actual
, Etype
(Formal
))
4012 (Etype
(Actual
) /= Universal_Integer
4013 or else not Is_Descendant_Of_Address
(Etype
(Formal
))
4014 or else In_Predefined_Unit
(N
))
4016 Next_Actual
(Actual
);
4017 Next_Formal
(Formal
);
4019 -- In Allow_Integer_Address mode, we allow an actual integer to
4020 -- match a formal address type and vice versa. We only do this
4021 -- if we are certain that an error will otherwise be issued
4023 elsif Address_Integer_Convert_OK
4024 (Etype
(Actual
), Etype
(Formal
))
4025 and then (Report
and not Is_Indexed
and not Is_Indirect
)
4027 -- Handle this case by introducing an unchecked conversion
4030 Unchecked_Convert_To
(Etype
(Formal
),
4031 Relocate_Node
(Actual
)));
4032 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
4033 Next_Actual
(Actual
);
4034 Next_Formal
(Formal
);
4036 -- Under relaxed RM semantics silently replace occurrences of
4037 -- null by System.Address_Null. We only do this if we know that
4038 -- an error will otherwise be issued.
4040 elsif Null_To_Null_Address_Convert_OK
(Actual
, Etype
(Formal
))
4041 and then (Report
and not Is_Indexed
and not Is_Indirect
)
4043 Replace_Null_By_Null_Address
(Actual
);
4044 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
4045 Next_Actual
(Actual
);
4046 Next_Formal
(Formal
);
4048 elsif Compatible_Types_In_Predicate
4049 (Etype
(Formal
), Etype
(Actual
))
4051 Next_Actual
(Actual
);
4052 Next_Formal
(Formal
);
4054 -- A current instance used as an actual of a function,
4055 -- whose body has not been seen, may include a formal
4056 -- whose type is an incomplete view of an enclosing
4057 -- type declaration containing the current call (e.g.
4058 -- in the Expression for a component declaration).
4060 -- In this case, update the signature of the subprogram
4061 -- so the formal has the type of the full view.
4063 elsif Inside_Init_Proc
4064 and then Nkind
(Actual
) = N_Identifier
4065 and then Ekind
(Etype
(Formal
)) = E_Incomplete_Type
4066 and then Etype
(Actual
) = Full_View
(Etype
(Formal
))
4068 Set_Etype
(Formal
, Etype
(Actual
));
4069 Next_Actual
(Actual
);
4070 Next_Formal
(Formal
);
4072 -- Handle failed type check
4075 if Debug_Flag_E
then
4076 Write_Str
(" type checking fails in call ");
4077 Write_Int
(Int
(N
));
4078 Write_Str
(" with formal ");
4079 Write_Int
(Int
(Formal
));
4080 Write_Str
(" in subprogram ");
4081 Write_Int
(Int
(Nam
));
4085 -- Comment needed on the following test???
4087 if Report
and not Is_Indexed
and not Is_Indirect
then
4089 -- Ada 2005 (AI-251): Complete the error notification
4090 -- to help new Ada 2005 users.
4092 if Is_Class_Wide_Type
(Etype
(Formal
))
4093 and then Is_Interface
(Etype
(Etype
(Formal
)))
4094 and then not Interface_Present_In_Ancestor
4095 (Typ
=> Etype
(Actual
),
4096 Iface
=> Etype
(Etype
(Formal
)))
4099 ("(Ada 2005) does not implement interface }",
4100 Actual
, Etype
(Etype
(Formal
)));
4103 -- If we are going to output a secondary error message
4104 -- below, we need to have Wrong_Type output the main one.
4107 (Actual
, Etype
(Formal
), Multiple
=> All_Errors_Mode
);
4109 if Nkind
(Actual
) = N_Op_Eq
4110 and then Nkind
(Left_Opnd
(Actual
)) = N_Identifier
4112 Formal
:= First_Formal
(Nam
);
4113 while Present
(Formal
) loop
4114 if Chars
(Left_Opnd
(Actual
)) = Chars
(Formal
) then
4115 Error_Msg_N
-- CODEFIX
4116 ("possible misspelling of `='>`!", Actual
);
4120 Next_Formal
(Formal
);
4124 if All_Errors_Mode
then
4125 Error_Msg_Sloc
:= Sloc
(Nam
);
4127 if Etype
(Formal
) = Any_Type
then
4129 ("there is no legal actual parameter", Actual
);
4132 if Is_Overloadable
(Nam
)
4133 and then Present
(Alias
(Nam
))
4134 and then not Comes_From_Source
(Nam
)
4137 ("\\ =='> in call to inherited operation & #!",
4140 elsif Ekind
(Nam
) = E_Subprogram_Type
then
4142 Access_To_Subprogram_Typ
:
4143 constant Entity_Id
:=
4145 (Associated_Node_For_Itype
(Nam
));
4148 ("\\ =='> in call to dereference of &#!",
4149 Actual
, Access_To_Subprogram_Typ
);
4154 ("\\ =='> in call to &#!", Actual
, Nam
);
4164 -- Normalize_Actuals has verified that a default value exists
4165 -- for this formal. Current actual names a subsequent formal.
4167 Next_Formal
(Formal
);
4171 -- Due to our current model of controlled type expansion we may
4172 -- have resolved a user call to a non-visible controlled primitive
4173 -- since these inherited subprograms may be generated in the current
4174 -- scope. This is a side effect of the need for the expander to be
4175 -- able to resolve internally generated calls.
4177 -- Specifically, the issue appears when predefined controlled
4178 -- operations get called on a type extension whose parent is a
4179 -- private extension completed with a controlled extension - see
4183 -- type Par_Typ is tagged private;
4185 -- type Par_Typ is new Controlled with null record;
4188 -- procedure Main is
4189 -- type Ext_Typ is new Par_Typ with null record;
4192 -- Finalize (Obj); -- Will improperly resolve
4195 -- To avoid breaking privacy, Is_Hidden gets set elsewhere on such
4196 -- primitives, but we still need to verify that Nam is indeed a
4197 -- non-visible controlled subprogram. So, we do that here and issue
4198 -- the appropriate error.
4201 and then not In_Instance
4202 and then not Comes_From_Source
(Nam
)
4203 and then Comes_From_Source
(N
)
4205 -- Verify Nam is a non-visible controlled primitive
4207 and then Chars
(Nam
) in Name_Adjust
4210 and then Ekind
(Nam
) = E_Procedure
4211 and then Is_Controlled
(Etype
(First_Form
))
4212 and then No
(Next_Formal
(First_Form
))
4213 and then not Is_Visibly_Controlled
(Etype
(First_Form
))
4215 Error_Msg_Node_2
:= Etype
(First_Form
);
4216 Error_Msg_NE
("call to non-visible controlled primitive & on type"
4220 -- On exit, all actuals match
4222 Indicate_Name_And_Type
;
4224 end Analyze_One_Call
;
4226 ---------------------------
4227 -- Analyze_Operator_Call --
4228 ---------------------------
4230 procedure Analyze_Operator_Call
(N
: Node_Id
; Op_Id
: Entity_Id
) is
4231 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
4232 Act1
: constant Node_Id
:= First_Actual
(N
);
4233 Act2
: constant Node_Id
:= Next_Actual
(Act1
);
4236 -- Binary operator case
4238 if Present
(Act2
) then
4240 -- If more than two operands, then not binary operator after all
4242 if Present
(Next_Actual
(Act2
)) then
4246 -- Otherwise action depends on operator
4257 Find_Arithmetic_Types
(Act1
, Act2
, Op_Id
, N
);
4263 Find_Boolean_Types
(Act1
, Act2
, Op_Id
, N
);
4272 Find_Comparison_Equality_Types
(Act1
, Act2
, Op_Id
, N
);
4274 when Name_Op_Concat
=>
4275 Find_Concatenation_Types
(Act1
, Act2
, Op_Id
, N
);
4277 -- Is this when others, or should it be an abort???
4283 -- Unary operator case
4291 Find_Unary_Types
(Act1
, Op_Id
, N
);
4294 Find_Negation_Types
(Act1
, Op_Id
, N
);
4296 -- Is this when others correct, or should it be an abort???
4302 end Analyze_Operator_Call
;
4304 -------------------------------------------
4305 -- Analyze_Overloaded_Selected_Component --
4306 -------------------------------------------
4308 procedure Analyze_Overloaded_Selected_Component
(N
: Node_Id
) is
4309 Nam
: constant Node_Id
:= Prefix
(N
);
4310 Sel
: constant Node_Id
:= Selector_Name
(N
);
4317 Set_Etype
(Sel
, Any_Type
);
4319 Get_First_Interp
(Nam
, I
, It
);
4320 while Present
(It
.Typ
) loop
4321 if Is_Access_Type
(It
.Typ
) then
4322 T
:= Designated_Type
(It
.Typ
);
4323 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
4328 -- Locate the component. For a private prefix the selector can denote
4331 if Is_Record_Type
(T
) or else Is_Private_Type
(T
) then
4333 -- If the prefix is a class-wide type, the visible components are
4334 -- those of the base type.
4336 if Is_Class_Wide_Type
(T
) then
4340 Comp
:= First_Entity
(T
);
4341 while Present
(Comp
) loop
4342 if Chars
(Comp
) = Chars
(Sel
)
4343 and then Is_Visible_Component
(Comp
, Sel
)
4346 -- AI05-105: if the context is an object renaming with
4347 -- an anonymous access type, the expected type of the
4348 -- object must be anonymous. This is a name resolution rule.
4350 if Nkind
(Parent
(N
)) /= N_Object_Renaming_Declaration
4351 or else No
(Access_Definition
(Parent
(N
)))
4352 or else Is_Anonymous_Access_Type
(Etype
(Comp
))
4354 Set_Entity
(Sel
, Comp
);
4355 Set_Etype
(Sel
, Etype
(Comp
));
4356 Add_One_Interp
(N
, Etype
(Comp
), Etype
(Comp
));
4357 Check_Implicit_Dereference
(N
, Etype
(Comp
));
4359 -- This also specifies a candidate to resolve the name.
4360 -- Further overloading will be resolved from context.
4361 -- The selector name itself does not carry overloading
4364 Set_Etype
(Nam
, It
.Typ
);
4367 -- Named access type in the context of a renaming
4368 -- declaration with an access definition. Remove
4369 -- inapplicable candidate.
4378 elsif Is_Concurrent_Type
(T
) then
4379 Comp
:= First_Entity
(T
);
4380 while Present
(Comp
)
4381 and then Comp
/= First_Private_Entity
(T
)
4383 if Chars
(Comp
) = Chars
(Sel
) then
4384 if Is_Overloadable
(Comp
) then
4385 Add_One_Interp
(Sel
, Comp
, Etype
(Comp
));
4387 Set_Entity_With_Checks
(Sel
, Comp
);
4388 Generate_Reference
(Comp
, Sel
);
4391 Set_Etype
(Sel
, Etype
(Comp
));
4392 Set_Etype
(N
, Etype
(Comp
));
4393 Set_Etype
(Nam
, It
.Typ
);
4399 Set_Is_Overloaded
(N
, Is_Overloaded
(Sel
));
4402 Get_Next_Interp
(I
, It
);
4405 if Etype
(N
) = Any_Type
4406 and then not Try_Object_Operation
(N
)
4408 Error_Msg_NE
("undefined selector& for overloaded prefix", N
, Sel
);
4409 Set_Entity
(Sel
, Any_Id
);
4410 Set_Etype
(Sel
, Any_Type
);
4412 end Analyze_Overloaded_Selected_Component
;
4414 ----------------------------------
4415 -- Analyze_Qualified_Expression --
4416 ----------------------------------
4418 procedure Analyze_Qualified_Expression
(N
: Node_Id
) is
4419 Expr
: constant Node_Id
:= Expression
(N
);
4420 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
4430 if Nkind
(Enclosing_Declaration
(N
)) in
4431 N_Formal_Type_Declaration |
4432 N_Full_Type_Declaration |
4433 N_Incomplete_Type_Declaration |
4434 N_Protected_Type_Declaration |
4435 N_Private_Extension_Declaration |
4436 N_Private_Type_Declaration |
4437 N_Subtype_Declaration |
4438 N_Task_Type_Declaration
4439 and then T
= Defining_Identifier
(Enclosing_Declaration
(N
))
4441 Error_Msg_N
("current instance not allowed", Mark
);
4447 Analyze_Expression
(Expr
);
4449 if T
= Any_Type
then
4453 Check_Fully_Declared
(T
, N
);
4455 -- If expected type is class-wide, check for exact match before
4456 -- expansion, because if the expression is a dispatching call it
4457 -- may be rewritten as explicit dereference with class-wide result.
4458 -- If expression is overloaded, retain only interpretations that
4459 -- will yield exact matches.
4461 if Is_Class_Wide_Type
(T
) then
4462 if not Is_Overloaded
(Expr
) then
4463 if Base_Type
(Etype
(Expr
)) /= Base_Type
(T
)
4464 and then Etype
(Expr
) /= Raise_Type
4466 if Nkind
(Expr
) = N_Aggregate
then
4467 Error_Msg_N
("type of aggregate cannot be class-wide", Expr
);
4469 Wrong_Type
(Expr
, T
);
4474 Get_First_Interp
(Expr
, I
, It
);
4476 while Present
(It
.Nam
) loop
4477 if Base_Type
(It
.Typ
) /= Base_Type
(T
) then
4481 Get_Next_Interp
(I
, It
);
4485 end Analyze_Qualified_Expression
;
4487 -----------------------------------
4488 -- Analyze_Quantified_Expression --
4489 -----------------------------------
4491 procedure Analyze_Quantified_Expression
(N
: Node_Id
) is
4492 function Is_Empty_Range
(Typ
: Entity_Id
) return Boolean;
4493 -- Return True if the iterator is part of a quantified expression and
4494 -- the range is known to be statically empty.
4496 function No_Else_Or_Trivial_True
(If_Expr
: Node_Id
) return Boolean;
4497 -- Determine whether if expression If_Expr lacks an else part or if it
4498 -- has one, it evaluates to True.
4500 --------------------
4501 -- Is_Empty_Range --
4502 --------------------
4504 function Is_Empty_Range
(Typ
: Entity_Id
) return Boolean is
4506 return Is_Array_Type
(Typ
)
4507 and then Compile_Time_Known_Bounds
(Typ
)
4509 Expr_Value
(Type_Low_Bound
(Etype
(First_Index
(Typ
)))) >
4510 Expr_Value
(Type_High_Bound
(Etype
(First_Index
(Typ
))));
4513 -----------------------------
4514 -- No_Else_Or_Trivial_True --
4515 -----------------------------
4517 function No_Else_Or_Trivial_True
(If_Expr
: Node_Id
) return Boolean is
4518 Else_Expr
: constant Node_Id
:=
4519 Next
(Next
(First
(Expressions
(If_Expr
))));
4523 or else (Compile_Time_Known_Value
(Else_Expr
)
4524 and then Is_True
(Expr_Value
(Else_Expr
)));
4525 end No_Else_Or_Trivial_True
;
4529 Cond
: constant Node_Id
:= Condition
(N
);
4530 Loc
: constant Source_Ptr
:= Sloc
(N
);
4531 Loop_Id
: Entity_Id
;
4532 QE_Scop
: Entity_Id
;
4534 -- Start of processing for Analyze_Quantified_Expression
4537 -- Create a scope to emulate the loop-like behavior of the quantified
4538 -- expression. The scope is needed to provide proper visibility of the
4541 QE_Scop
:= New_Internal_Entity
(E_Loop
, Current_Scope
, Loc
, 'L');
4542 Set_Etype
(QE_Scop
, Standard_Void_Type
);
4543 Set_Scope
(QE_Scop
, Current_Scope
);
4544 Set_Parent
(QE_Scop
, N
);
4546 Push_Scope
(QE_Scop
);
4548 -- All constituents are preanalyzed and resolved to avoid untimely
4549 -- generation of various temporaries and types. Full analysis and
4550 -- expansion is carried out when the quantified expression is
4551 -- transformed into an expression with actions.
4553 if Present
(Iterator_Specification
(N
)) then
4554 Preanalyze
(Iterator_Specification
(N
));
4556 -- Do not proceed with the analysis when the range of iteration is
4559 if Is_Entity_Name
(Name
(Iterator_Specification
(N
)))
4560 and then Is_Empty_Range
(Etype
(Name
(Iterator_Specification
(N
))))
4562 Preanalyze_And_Resolve
(Condition
(N
), Standard_Boolean
);
4565 -- Emit a warning and replace expression with its static value
4567 if All_Present
(N
) then
4569 ("??quantified expression with ALL "
4570 & "over a null range has value True", N
);
4571 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
4575 ("??quantified expression with SOME "
4576 & "over a null range has value False", N
);
4577 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
4584 else pragma Assert
(Present
(Loop_Parameter_Specification
(N
)));
4586 Loop_Par
: constant Node_Id
:= Loop_Parameter_Specification
(N
);
4589 Preanalyze
(Loop_Par
);
4591 if Nkind
(Discrete_Subtype_Definition
(Loop_Par
)) = N_Function_Call
4592 and then Parent
(Loop_Par
) /= N
4594 -- The parser cannot distinguish between a loop specification
4595 -- and an iterator specification. If after preanalysis the
4596 -- proper form has been recognized, rewrite the expression to
4597 -- reflect the right kind. This is needed for proper ASIS
4598 -- navigation. If expansion is enabled, the transformation is
4599 -- performed when the expression is rewritten as a loop.
4600 -- Is this still needed???
4602 Set_Iterator_Specification
(N
,
4603 New_Copy_Tree
(Iterator_Specification
(Parent
(Loop_Par
))));
4605 Set_Defining_Identifier
(Iterator_Specification
(N
),
4606 Relocate_Node
(Defining_Identifier
(Loop_Par
)));
4607 Set_Name
(Iterator_Specification
(N
),
4608 Relocate_Node
(Discrete_Subtype_Definition
(Loop_Par
)));
4609 Set_Comes_From_Source
(Iterator_Specification
(N
),
4610 Comes_From_Source
(Loop_Parameter_Specification
(N
)));
4611 Set_Loop_Parameter_Specification
(N
, Empty
);
4616 Preanalyze_And_Resolve
(Cond
, Standard_Boolean
);
4619 Set_Etype
(N
, Standard_Boolean
);
4621 -- Verify that the loop variable is used within the condition of the
4622 -- quantified expression.
4624 if Present
(Iterator_Specification
(N
)) then
4625 Loop_Id
:= Defining_Identifier
(Iterator_Specification
(N
));
4627 Loop_Id
:= Defining_Identifier
(Loop_Parameter_Specification
(N
));
4631 type Subexpr_Kind
is (Full
, Conjunct
, Disjunct
);
4633 procedure Check_Subexpr
(Expr
: Node_Id
; Kind
: Subexpr_Kind
);
4634 -- Check that the quantified variable appears in every sub-expression
4635 -- of the quantified expression. If Kind is Full, Expr is the full
4636 -- expression. If Kind is Conjunct (resp. Disjunct), Expr is a
4637 -- conjunct (resp. disjunct) of the full expression.
4643 procedure Check_Subexpr
(Expr
: Node_Id
; Kind
: Subexpr_Kind
) is
4645 if Nkind
(Expr
) in N_Op_And | N_And_Then
4646 and then Kind
/= Disjunct
4648 Check_Subexpr
(Left_Opnd
(Expr
), Conjunct
);
4649 Check_Subexpr
(Right_Opnd
(Expr
), Conjunct
);
4651 elsif Nkind
(Expr
) in N_Op_Or | N_Or_Else
4652 and then Kind
/= Conjunct
4654 Check_Subexpr
(Left_Opnd
(Expr
), Disjunct
);
4655 Check_Subexpr
(Right_Opnd
(Expr
), Disjunct
);
4658 and then not Referenced
(Loop_Id
, Expr
)
4661 Sub
: constant String :=
4662 (if Kind
= Conjunct
then "conjunct" else "disjunct");
4665 ("?.t?unused variable & in " & Sub
, Expr
, Loop_Id
);
4667 ("\consider extracting " & Sub
& " from quantified "
4668 & "expression", Expr
, Loop_Id
);
4674 if Warn_On_Suspicious_Contract
4675 and then not Is_Internal_Name
(Chars
(Loop_Id
))
4677 -- Generating C, this check causes spurious warnings on inlined
4678 -- postconditions; we can safely disable it because this check
4679 -- was previously performed when analyzing the internally built
4680 -- postconditions procedure.
4682 and then not (Modify_Tree_For_C
and In_Inlined_Body
)
4684 if not Referenced
(Loop_Id
, Cond
) then
4685 Error_Msg_N
("?.t?unused variable &", Loop_Id
);
4687 Check_Subexpr
(Cond
, Kind
=> Full
);
4692 -- Diagnose a possible misuse of the SOME existential quantifier. When
4693 -- we have a quantified expression of the form:
4695 -- for some X => (if P then Q [else True])
4697 -- any value for X that makes P False results in the if expression being
4698 -- trivially True, and so also results in the quantified expression
4699 -- being trivially True.
4701 if Warn_On_Suspicious_Contract
4702 and then not All_Present
(N
)
4703 and then Nkind
(Cond
) = N_If_Expression
4704 and then No_Else_Or_Trivial_True
(Cond
)
4706 Error_Msg_N
("?.t?suspicious expression", N
);
4707 Error_Msg_N
("\\did you mean (for all X ='> (if P then Q))", N
);
4708 Error_Msg_N
("\\or (for some X ='> P and then Q) instead'?", N
);
4710 end Analyze_Quantified_Expression
;
4716 procedure Analyze_Range
(N
: Node_Id
) is
4717 L
: constant Node_Id
:= Low_Bound
(N
);
4718 H
: constant Node_Id
:= High_Bound
(N
);
4719 I1
, I2
: Interp_Index
;
4722 procedure Check_Common_Type
(T1
, T2
: Entity_Id
);
4723 -- Verify the compatibility of two types, and choose the
4724 -- non universal one if the other is universal.
4726 procedure Check_High_Bound
(T
: Entity_Id
);
4727 -- Test one interpretation of the low bound against all those
4728 -- of the high bound.
4730 procedure Check_Universal_Expression
(N
: Node_Id
);
4731 -- In Ada 83, reject bounds of a universal range that are not literals
4734 -----------------------
4735 -- Check_Common_Type --
4736 -----------------------
4738 procedure Check_Common_Type
(T1
, T2
: Entity_Id
) is
4740 if Covers
(T1
=> T1
, T2
=> T2
)
4742 Covers
(T1
=> T2
, T2
=> T1
)
4744 if Is_Universal_Numeric_Type
(T1
)
4745 or else T1
= Any_Character
4747 Add_One_Interp
(N
, Base_Type
(T2
), Base_Type
(T2
));
4750 Add_One_Interp
(N
, T1
, T1
);
4753 Add_One_Interp
(N
, Base_Type
(T1
), Base_Type
(T1
));
4756 end Check_Common_Type
;
4758 ----------------------
4759 -- Check_High_Bound --
4760 ----------------------
4762 procedure Check_High_Bound
(T
: Entity_Id
) is
4764 if not Is_Overloaded
(H
) then
4765 Check_Common_Type
(T
, Etype
(H
));
4767 Get_First_Interp
(H
, I2
, It2
);
4768 while Present
(It2
.Typ
) loop
4769 Check_Common_Type
(T
, It2
.Typ
);
4770 Get_Next_Interp
(I2
, It2
);
4773 end Check_High_Bound
;
4775 --------------------------------
4776 -- Check_Universal_Expression --
4777 --------------------------------
4779 procedure Check_Universal_Expression
(N
: Node_Id
) is
4781 if Etype
(N
) = Universal_Integer
4782 and then Nkind
(N
) /= N_Integer_Literal
4783 and then not Is_Entity_Name
(N
)
4784 and then Nkind
(N
) /= N_Attribute_Reference
4786 Error_Msg_N
("illegal bound in discrete range", N
);
4788 end Check_Universal_Expression
;
4790 -- Start of processing for Analyze_Range
4793 Set_Etype
(N
, Any_Type
);
4794 Analyze_Expression
(L
);
4795 Analyze_Expression
(H
);
4797 if Etype
(L
) = Any_Type
or else Etype
(H
) = Any_Type
then
4801 if not Is_Overloaded
(L
) then
4802 Check_High_Bound
(Etype
(L
));
4804 Get_First_Interp
(L
, I1
, It1
);
4805 while Present
(It1
.Typ
) loop
4806 Check_High_Bound
(It1
.Typ
);
4807 Get_Next_Interp
(I1
, It1
);
4811 -- If result is Any_Type, then we did not find a compatible pair
4813 if Etype
(N
) = Any_Type
then
4814 Error_Msg_N
("incompatible types in range", N
);
4818 if Ada_Version
= Ada_83
4820 (Nkind
(Parent
(N
)) = N_Loop_Parameter_Specification
4821 or else Nkind
(Parent
(N
)) = N_Constrained_Array_Definition
)
4823 Check_Universal_Expression
(L
);
4824 Check_Universal_Expression
(H
);
4827 Check_Function_Writable_Actuals
(N
);
4830 -----------------------
4831 -- Analyze_Reference --
4832 -----------------------
4834 procedure Analyze_Reference
(N
: Node_Id
) is
4835 P
: constant Node_Id
:= Prefix
(N
);
4838 Acc_Type
: Entity_Id
;
4843 -- An interesting error check, if we take the 'Ref of an object for
4844 -- which a pragma Atomic or Volatile has been given, and the type of the
4845 -- object is not Atomic or Volatile, then we are in trouble. The problem
4846 -- is that no trace of the atomic/volatile status will remain for the
4847 -- backend to respect when it deals with the resulting pointer, since
4848 -- the pointer type will not be marked atomic (it is a pointer to the
4849 -- base type of the object).
4851 -- It is not clear if that can ever occur, but in case it does, we will
4852 -- generate an error message. Not clear if this message can ever be
4853 -- generated, and pretty clear that it represents a bug if it is, still
4854 -- seems worth checking, except in CodePeer mode where we do not really
4855 -- care and don't want to bother the user.
4859 if Is_Entity_Name
(P
)
4860 and then Is_Object_Reference
(P
)
4861 and then not CodePeer_Mode
4866 if (Has_Atomic_Components
(E
)
4867 and then not Has_Atomic_Components
(T
))
4869 (Has_Volatile_Components
(E
)
4870 and then not Has_Volatile_Components
(T
))
4871 or else (Is_Atomic
(E
) and then not Is_Atomic
(T
))
4872 or else (Is_Volatile
(E
) and then not Is_Volatile
(T
))
4874 Error_Msg_N
("cannot take reference to Atomic/Volatile object", N
);
4878 -- Carry on with normal processing
4880 Acc_Type
:= Create_Itype
(E_Allocator_Type
, N
);
4881 Set_Etype
(Acc_Type
, Acc_Type
);
4882 Set_Directly_Designated_Type
(Acc_Type
, Etype
(P
));
4883 Set_Etype
(N
, Acc_Type
);
4884 end Analyze_Reference
;
4886 --------------------------------
4887 -- Analyze_Selected_Component --
4888 --------------------------------
4890 -- Prefix is a record type or a task or protected type. In the latter case,
4891 -- the selector must denote a visible entry.
4893 procedure Analyze_Selected_Component
(N
: Node_Id
) is
4894 Name
: constant Node_Id
:= Prefix
(N
);
4895 Sel
: constant Node_Id
:= Selector_Name
(N
);
4897 Comp
: Entity_Id
:= Empty
;
4898 Has_Candidate
: Boolean := False;
4899 Hidden_Comp
: Entity_Id
;
4901 Is_Private_Op
: Boolean;
4903 Prefix_Type
: Entity_Id
;
4905 Type_To_Use
: Entity_Id
;
4906 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
4907 -- a class-wide type, we use its root type, whose components are
4908 -- present in the class-wide type.
4910 Is_Single_Concurrent_Object
: Boolean;
4911 -- Set True if the prefix is a single task or a single protected object
4913 function Constraint_Has_Unprefixed_Discriminant_Reference
4914 (Typ
: Entity_Id
) return Boolean;
4915 -- Given a subtype that is subject to a discriminant-dependent
4916 -- constraint, returns True if any of the values of the constraint
4917 -- (i.e., any of the index values for an index constraint, any of
4918 -- the discriminant values for a discriminant constraint)
4919 -- are unprefixed discriminant names.
4921 function Has_Mode_Conformant_Spec
(Comp
: Entity_Id
) return Boolean;
4922 -- It is known that the parent of N denotes a subprogram call. Comp
4923 -- is an overloadable component of the concurrent type of the prefix.
4924 -- Determine whether all formals of the parent of N and Comp are mode
4925 -- conformant. If the parent node is not analyzed yet it may be an
4926 -- indexed component rather than a function call.
4928 function Has_Dereference
(Nod
: Node_Id
) return Boolean;
4929 -- Check whether prefix includes a dereference, explicit or implicit,
4930 -- at any recursive level.
4932 function Try_By_Protected_Procedure_Prefixed_View
return Boolean;
4933 -- Return True if N is an access attribute whose prefix is a prefixed
4934 -- class-wide (synchronized or protected) interface view for which some
4935 -- interpretation is a procedure with synchronization kind By_Protected
4936 -- _Procedure, and collect all its interpretations (since it may be an
4937 -- overloaded interface primitive); otherwise return False.
4939 function Try_Selected_Component_In_Instance
4940 (Typ
: Entity_Id
) return Boolean;
4941 -- If Typ is the actual for a formal derived type, or a derived type
4942 -- thereof, the component inherited from the generic parent may not
4943 -- be visible in the actual, but the selected component is legal. Climb
4944 -- up the derivation chain of the generic parent type and return True if
4945 -- we find the proper ancestor type; otherwise return False.
4947 ------------------------------------------------------
4948 -- Constraint_Has_Unprefixed_Discriminant_Reference --
4949 ------------------------------------------------------
4951 function Constraint_Has_Unprefixed_Discriminant_Reference
4952 (Typ
: Entity_Id
) return Boolean
4954 function Is_Discriminant_Name
(N
: Node_Id
) return Boolean is
4955 (Nkind
(N
) = N_Identifier
4956 and then Ekind
(Entity
(N
)) = E_Discriminant
);
4958 if Is_Array_Type
(Typ
) then
4960 Index
: Node_Id
:= First_Index
(Typ
);
4963 while Present
(Index
) loop
4965 if Nkind
(Rng
) = N_Subtype_Indication
then
4966 Rng
:= Range_Expression
(Constraint
(Rng
));
4969 if Nkind
(Rng
) = N_Range
then
4970 if Is_Discriminant_Name
(Low_Bound
(Rng
))
4971 or else Is_Discriminant_Name
(High_Bound
(Rng
))
4982 Elmt
: Elmt_Id
:= First_Elmt
(Discriminant_Constraint
(Typ
));
4984 while Present
(Elmt
) loop
4985 if Is_Discriminant_Name
(Node
(Elmt
)) then
4994 end Constraint_Has_Unprefixed_Discriminant_Reference
;
4996 ------------------------------
4997 -- Has_Mode_Conformant_Spec --
4998 ------------------------------
5000 function Has_Mode_Conformant_Spec
(Comp
: Entity_Id
) return Boolean is
5001 Comp_Param
: Entity_Id
;
5003 Param_Typ
: Entity_Id
;
5006 Comp_Param
:= First_Formal
(Comp
);
5008 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
5009 Param
:= First
(Expressions
(Parent
(N
)));
5011 Param
:= First
(Parameter_Associations
(Parent
(N
)));
5014 while Present
(Comp_Param
)
5015 and then Present
(Param
)
5017 Param_Typ
:= Find_Parameter_Type
(Param
);
5019 if Present
(Param_Typ
)
5021 not Conforming_Types
5022 (Etype
(Comp_Param
), Param_Typ
, Mode_Conformant
)
5027 Next_Formal
(Comp_Param
);
5031 -- One of the specs has additional formals; there is no match, unless
5032 -- this may be an indexing of a parameterless call.
5034 -- Note that when expansion is disabled, the corresponding record
5035 -- type of synchronized types is not constructed, so that there is
5036 -- no point is attempting an interpretation as a prefixed call, as
5037 -- this is bound to fail because the primitive operations will not
5038 -- be properly located.
5040 if Present
(Comp_Param
) or else Present
(Param
) then
5041 if Needs_No_Actuals
(Comp
)
5042 and then Is_Array_Type
(Etype
(Comp
))
5043 and then not Expander_Active
5052 end Has_Mode_Conformant_Spec
;
5054 ---------------------
5055 -- Has_Dereference --
5056 ---------------------
5058 function Has_Dereference
(Nod
: Node_Id
) return Boolean is
5060 if Nkind
(Nod
) = N_Explicit_Dereference
then
5063 elsif Is_Access_Type
(Etype
(Nod
)) then
5066 elsif Nkind
(Nod
) in N_Indexed_Component | N_Selected_Component
then
5067 return Has_Dereference
(Prefix
(Nod
));
5072 end Has_Dereference
;
5074 ----------------------------------------------
5075 -- Try_By_Protected_Procedure_Prefixed_View --
5076 ----------------------------------------------
5078 function Try_By_Protected_Procedure_Prefixed_View
return Boolean is
5079 Candidate
: Node_Id
:= Empty
;
5084 if Nkind
(Parent
(N
)) = N_Attribute_Reference
5085 and then Attribute_Name
(Parent
(N
)) in
5087 | Name_Unchecked_Access
5088 | Name_Unrestricted_Access
5089 and then Is_Class_Wide_Type
(Prefix_Type
)
5090 and then (Is_Synchronized_Interface
(Prefix_Type
)
5091 or else Is_Protected_Interface
(Prefix_Type
))
5093 -- If we have not found yet any interpretation then mark this
5094 -- one as the first interpretation (cf. Add_One_Interp).
5096 if No
(Etype
(Sel
)) then
5097 Set_Etype
(Sel
, Any_Type
);
5100 Elmt
:= First_Elmt
(Primitive_Operations
(Etype
(Prefix_Type
)));
5101 while Present
(Elmt
) loop
5102 Prim
:= Node
(Elmt
);
5104 if Chars
(Prim
) = Chars
(Sel
)
5105 and then Is_By_Protected_Procedure
(Prim
)
5107 Candidate
:= New_Copy
(Prim
);
5109 -- Skip the controlling formal; required to check type
5110 -- conformance of the target access to protected type
5111 -- (see Conforming_Types).
5113 Set_First_Entity
(Candidate
,
5114 Next_Entity
(First_Entity
(Prim
)));
5116 Add_One_Interp
(Sel
, Candidate
, Etype
(Prim
));
5117 Set_Etype
(N
, Etype
(Prim
));
5124 -- Propagate overloaded attribute
5126 if Present
(Candidate
) and then Is_Overloaded
(Sel
) then
5127 Set_Is_Overloaded
(N
);
5130 return Present
(Candidate
);
5131 end Try_By_Protected_Procedure_Prefixed_View
;
5133 ----------------------------------------
5134 -- Try_Selected_Component_In_Instance --
5135 ----------------------------------------
5137 function Try_Selected_Component_In_Instance
5138 (Typ
: Entity_Id
) return Boolean
5140 procedure Find_Component_In_Instance
(Rec
: Entity_Id
);
5141 -- In an instance, a component of a private extension may not be
5142 -- visible while it was visible in the generic. Search candidate
5143 -- scope for a component with the proper identifier. If a match is
5144 -- found, the Etype of both N and Sel are set from this component,
5145 -- and the entity of Sel is set to reference this component. If no
5146 -- match is found, Entity (Sel) remains unset. For a derived type
5147 -- that is an actual of the instance, the desired component may be
5148 -- found in any ancestor.
5150 --------------------------------
5151 -- Find_Component_In_Instance --
5152 --------------------------------
5154 procedure Find_Component_In_Instance
(Rec
: Entity_Id
) is
5160 while Present
(Typ
) loop
5161 Comp
:= First_Component
(Typ
);
5162 while Present
(Comp
) loop
5163 if Chars
(Comp
) = Chars
(Sel
) then
5164 Set_Entity_With_Checks
(Sel
, Comp
);
5165 Set_Etype
(Sel
, Etype
(Comp
));
5166 Set_Etype
(N
, Etype
(Comp
));
5170 Next_Component
(Comp
);
5173 -- If not found, the component may be declared in the parent
5174 -- type or its full view, if any.
5176 if Is_Derived_Type
(Typ
) then
5179 if Is_Private_Type
(Typ
) then
5180 Typ
:= Full_View
(Typ
);
5188 -- If we fall through, no match, so no changes made
5191 end Find_Component_In_Instance
;
5197 -- Start of processing for Try_Selected_Component_In_Instance
5200 pragma Assert
(In_Instance
and then Is_Tagged_Type
(Typ
));
5201 pragma Assert
(Etype
(N
) = Any_Type
);
5203 -- Climb up derivation chain to generic actual subtype
5206 while not Is_Generic_Actual_Type
(Par
) loop
5207 if Ekind
(Par
) = E_Record_Type
then
5208 Par
:= Parent_Subtype
(Par
);
5211 exit when Par
= Etype
(Par
);
5216 -- If Par is a generic actual, look for component in ancestor types.
5217 -- Skip this if we have no Declaration_Node, as is the case for
5221 and then Is_Generic_Actual_Type
(Par
)
5222 and then Present
(Declaration_Node
(Par
))
5224 Par
:= Generic_Parent_Type
(Declaration_Node
(Par
));
5226 Find_Component_In_Instance
(Par
);
5227 exit when Present
(Entity
(Sel
))
5228 or else Par
= Etype
(Par
);
5232 -- Another special case: the type is an extension of a private
5233 -- type T, either is an actual in an instance or is immediately
5234 -- visible, and we are in the body of the instance, which means
5235 -- the generic body had a full view of the type declaration for
5236 -- T or some ancestor that defines the component in question.
5237 -- This happens because Is_Visible_Component returned False on
5238 -- this component, as T or the ancestor is still private since
5239 -- the Has_Private_View mechanism is bypassed because T or the
5240 -- ancestor is not directly referenced in the generic body.
5242 elsif Is_Derived_Type
(Typ
)
5243 and then (Used_As_Generic_Actual
(Typ
)
5244 or else Is_Immediately_Visible
(Typ
))
5245 and then In_Instance_Body
5247 Find_Component_In_Instance
(Parent_Subtype
(Typ
));
5250 return Etype
(N
) /= Any_Type
;
5251 end Try_Selected_Component_In_Instance
;
5253 -- Start of processing for Analyze_Selected_Component
5256 Set_Etype
(N
, Any_Type
);
5258 if Is_Overloaded
(Name
) then
5259 Analyze_Overloaded_Selected_Component
(N
);
5262 elsif Etype
(Name
) = Any_Type
then
5263 Set_Entity
(Sel
, Any_Id
);
5264 Set_Etype
(Sel
, Any_Type
);
5268 Prefix_Type
:= Etype
(Name
);
5271 if Is_Access_Type
(Prefix_Type
) then
5273 -- A RACW object can never be used as prefix of a selected component
5274 -- since that means it is dereferenced without being a controlling
5275 -- operand of a dispatching operation (RM E.2.2(16/1)). Before
5276 -- reporting an error, we must check whether this is actually a
5277 -- dispatching call in prefix form.
5279 if Is_Remote_Access_To_Class_Wide_Type
(Prefix_Type
)
5280 and then Comes_From_Source
(N
)
5282 if Try_Object_Operation
(N
) then
5286 ("invalid dereference of a remote access-to-class-wide value",
5290 -- Normal case of selected component applied to access type
5293 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
5294 Prefix_Type
:= Implicitly_Designated_Type
(Prefix_Type
);
5297 -- If we have an explicit dereference of a remote access-to-class-wide
5298 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
5299 -- have to check for the case of a prefix that is a controlling operand
5300 -- of a prefixed dispatching call, as the dereference is legal in that
5301 -- case. Normally this condition is checked in Validate_Remote_Access_
5302 -- To_Class_Wide_Type, but we have to defer the checking for selected
5303 -- component prefixes because of the prefixed dispatching call case.
5304 -- Note that implicit dereferences are checked for this just above.
5306 elsif Nkind
(Name
) = N_Explicit_Dereference
5307 and then Is_Remote_Access_To_Class_Wide_Type
(Etype
(Prefix
(Name
)))
5308 and then Comes_From_Source
(N
)
5310 if Try_Object_Operation
(N
) then
5314 ("invalid dereference of a remote access-to-class-wide value",
5319 -- (Ada 2005): if the prefix is the limited view of a type, and
5320 -- the context already includes the full view, use the full view
5321 -- in what follows, either to retrieve a component of to find
5322 -- a primitive operation. If the prefix is an explicit dereference,
5323 -- set the type of the prefix to reflect this transformation.
5324 -- If the nonlimited view is itself an incomplete type, get the
5325 -- full view if available.
5327 if From_Limited_With
(Prefix_Type
)
5328 and then Has_Non_Limited_View
(Prefix_Type
)
5330 Prefix_Type
:= Get_Full_View
(Non_Limited_View
(Prefix_Type
));
5332 if Nkind
(N
) = N_Explicit_Dereference
then
5333 Set_Etype
(Prefix
(N
), Prefix_Type
);
5337 if Ekind
(Prefix_Type
) = E_Private_Subtype
then
5338 Prefix_Type
:= Base_Type
(Prefix_Type
);
5341 Type_To_Use
:= Prefix_Type
;
5343 -- For class-wide types, use the entity list of the root type. This
5344 -- indirection is specially important for private extensions because
5345 -- only the root type get switched (not the class-wide type).
5347 if Is_Class_Wide_Type
(Prefix_Type
) then
5348 Type_To_Use
:= Root_Type
(Prefix_Type
);
5351 -- If the prefix is a single concurrent object, use its name in error
5352 -- messages, rather than that of its anonymous type.
5354 Is_Single_Concurrent_Object
:=
5355 Is_Concurrent_Type
(Prefix_Type
)
5356 and then Is_Internal_Name
(Chars
(Prefix_Type
))
5357 and then not Is_Derived_Type
(Prefix_Type
)
5358 and then Is_Entity_Name
(Name
);
5360 -- Avoid initializing Comp if that initialization is not needed
5361 -- (and, more importantly, if the call to First_Entity could fail).
5363 if Has_Discriminants
(Type_To_Use
)
5364 or else Is_Record_Type
(Type_To_Use
)
5365 or else Is_Private_Type
(Type_To_Use
)
5366 or else Is_Concurrent_Type
(Type_To_Use
)
5368 Comp
:= First_Entity
(Type_To_Use
);
5371 -- If the selector has an original discriminant, the node appears in
5372 -- an instance. Replace the discriminant with the corresponding one
5373 -- in the current discriminated type. For nested generics, this must
5374 -- be done transitively, so note the new original discriminant.
5376 if Nkind
(Sel
) = N_Identifier
5377 and then In_Instance
5378 and then Present
(Original_Discriminant
(Sel
))
5380 Comp
:= Find_Corresponding_Discriminant
(Sel
, Prefix_Type
);
5382 -- Mark entity before rewriting, for completeness and because
5383 -- subsequent semantic checks might examine the original node.
5385 Set_Entity
(Sel
, Comp
);
5386 Rewrite
(Selector_Name
(N
), New_Occurrence_Of
(Comp
, Sloc
(N
)));
5387 Set_Original_Discriminant
(Selector_Name
(N
), Comp
);
5388 Set_Etype
(N
, Etype
(Comp
));
5389 Check_Implicit_Dereference
(N
, Etype
(Comp
));
5391 elsif Is_Record_Type
(Prefix_Type
) then
5393 -- Find a component with the given name. If the node is a prefixed
5394 -- call, do not examine components whose visibility may be
5397 while Present
(Comp
)
5398 and then not Is_Prefixed_Call
(N
)
5400 -- When the selector has been resolved to a function then we may be
5401 -- looking at a prefixed call which has been preanalyzed already as
5402 -- part of a class condition. In such cases it is possible for a
5403 -- derived type to declare a component which has the same name as
5404 -- a primitive used in a parent's class condition.
5406 -- Avoid seeing components as possible interpretations of the
5407 -- selected component when this is true.
5409 and then not (Inside_Class_Condition_Preanalysis
5410 and then Present
(Entity
(Sel
))
5411 and then Ekind
(Entity
(Sel
)) = E_Function
)
5413 if Chars
(Comp
) = Chars
(Sel
)
5414 and then Is_Visible_Component
(Comp
, N
)
5416 Set_Entity_With_Checks
(Sel
, Comp
);
5417 Set_Etype
(Sel
, Etype
(Comp
));
5419 if Ekind
(Comp
) = E_Discriminant
then
5420 if Is_Unchecked_Union
(Base_Type
(Prefix_Type
)) then
5422 ("cannot reference discriminant of unchecked union",
5426 if Is_Generic_Type
(Prefix_Type
)
5428 Is_Generic_Type
(Root_Type
(Prefix_Type
))
5430 Set_Original_Discriminant
(Sel
, Comp
);
5434 -- Resolve the prefix early otherwise it is not possible to
5435 -- build the actual subtype of the component: it may need
5436 -- to duplicate this prefix and duplication is only allowed
5437 -- on fully resolved expressions.
5441 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
5442 -- subtypes in a package specification.
5445 -- limited with Pkg;
5447 -- type Acc_Inc is access Pkg.T;
5449 -- N : Natural := X.all.Comp; -- ERROR, limited view
5450 -- end Pkg; -- Comp is not visible
5452 if Nkind
(Name
) = N_Explicit_Dereference
5453 and then From_Limited_With
(Etype
(Prefix
(Name
)))
5454 and then not Is_Potentially_Use_Visible
(Etype
(Name
))
5455 and then Nkind
(Parent
(Cunit_Entity
(Current_Sem_Unit
))) =
5456 N_Package_Specification
5459 ("premature usage of incomplete}", Prefix
(Name
),
5460 Etype
(Prefix
(Name
)));
5463 -- We never need an actual subtype for the case of a selection
5464 -- for a indexed component of a non-packed array, since in
5465 -- this case gigi generates all the checks and can find the
5466 -- necessary bounds information.
5468 -- We also do not need an actual subtype for the case of a
5469 -- first, last, length, or range attribute applied to a
5470 -- non-packed array, since gigi can again get the bounds in
5471 -- these cases (gigi cannot handle the packed case, since it
5472 -- has the bounds of the packed array type, not the original
5473 -- bounds of the type). However, if the prefix is itself a
5474 -- selected component, as in a.b.c (i), gigi may regard a.b.c
5475 -- as a dynamic-sized temporary, so we do generate an actual
5476 -- subtype for this case.
5478 Parent_N
:= Parent
(N
);
5480 if not Is_Packed
(Etype
(Comp
))
5482 ((Nkind
(Parent_N
) = N_Indexed_Component
5483 and then Nkind
(Name
) /= N_Selected_Component
)
5485 (Nkind
(Parent_N
) = N_Attribute_Reference
5487 Attribute_Name
(Parent_N
) in Name_First
5492 Set_Etype
(N
, Etype
(Comp
));
5494 -- If full analysis is not enabled, we do not generate an
5495 -- actual subtype, because in the absence of expansion
5496 -- reference to a formal of a protected type, for example,
5497 -- will not be properly transformed, and will lead to
5498 -- out-of-scope references in gigi.
5500 -- In all other cases, we currently build an actual subtype.
5501 -- It seems likely that many of these cases can be avoided,
5502 -- but right now, the front end makes direct references to the
5503 -- bounds (e.g. in generating a length check), and if we do
5504 -- not make an actual subtype, we end up getting a direct
5505 -- reference to a discriminant, which will not do.
5507 elsif Full_Analysis
then
5509 Build_Actual_Subtype_Of_Component
(Etype
(Comp
), N
);
5510 Insert_Action
(N
, Act_Decl
);
5512 if No
(Act_Decl
) then
5513 Set_Etype
(N
, Etype
(Comp
));
5516 -- If discriminants were present in the component
5517 -- declaration, they have been replaced by the
5518 -- actual values in the prefix object.
5521 Subt
: constant Entity_Id
:=
5522 Defining_Identifier
(Act_Decl
);
5524 Set_Etype
(Subt
, Base_Type
(Etype
(Comp
)));
5525 Set_Etype
(N
, Subt
);
5529 -- If Etype (Comp) is an access type whose designated subtype
5530 -- is constrained by an unprefixed discriminant value,
5531 -- then ideally we would build a new subtype with an
5532 -- appropriately prefixed discriminant value and use that
5533 -- instead, as is done in Build_Actual_Subtype_Of_Component.
5534 -- That turns out to be difficult in this context (with
5535 -- Full_Analysis = False, we could be processing a selected
5536 -- component that occurs in a Postcondition pragma;
5537 -- PPC pragmas are odd because they can contain references
5538 -- to formal parameters that occur outside the subprogram).
5539 -- So instead we punt on building a new subtype and we
5540 -- use the base type instead. This might introduce
5541 -- correctness problems if N were the target of an
5542 -- assignment (because a required check might be omitted);
5543 -- fortunately, that's impossible because a reference to the
5544 -- current instance of a type does not denote a variable view
5545 -- when the reference occurs within an aspect_specification.
5546 -- GNAT's Precondition and Postcondition pragmas follow the
5547 -- same rules as a Pre or Post aspect_specification.
5549 elsif Has_Discriminant_Dependent_Constraint
(Comp
)
5550 and then Ekind
(Etype
(Comp
)) = E_Access_Subtype
5551 and then Constraint_Has_Unprefixed_Discriminant_Reference
5552 (Designated_Type
(Etype
(Comp
)))
5554 Set_Etype
(N
, Base_Type
(Etype
(Comp
)));
5556 -- If Full_Analysis not enabled, just set the Etype
5559 Set_Etype
(N
, Etype
(Comp
));
5562 Check_Implicit_Dereference
(N
, Etype
(N
));
5566 -- If the prefix is a private extension, check only the visible
5567 -- components of the partial view. This must include the tag,
5568 -- which can appear in expanded code in a tag check.
5570 if Ekind
(Type_To_Use
) = E_Record_Type_With_Private
5571 and then Chars
(Selector_Name
(N
)) /= Name_uTag
5573 exit when Comp
= Last_Entity
(Type_To_Use
);
5579 -- Ada 2005 (AI-252): The selected component can be interpreted as
5580 -- a prefixed view of a subprogram. Depending on the context, this is
5581 -- either a name that can appear in a renaming declaration, or part
5582 -- of an enclosing call given in prefix form.
5584 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
5585 -- selected component should resolve to a name.
5587 -- Extension feature: Also support calls with prefixed views for
5588 -- untagged record types.
5590 if Ada_Version
>= Ada_2005
5591 and then (Is_Tagged_Type
(Prefix_Type
)
5592 or else Core_Extensions_Allowed
)
5593 and then not Is_Concurrent_Type
(Prefix_Type
)
5595 if Nkind
(Parent
(N
)) = N_Generic_Association
5596 or else Nkind
(Parent
(N
)) = N_Requeue_Statement
5597 or else Nkind
(Parent
(N
)) = N_Subprogram_Renaming_Declaration
5599 if Find_Primitive_Operation
(N
) then
5603 elsif Try_By_Protected_Procedure_Prefixed_View
then
5606 -- If the prefix type is the actual for a formal derived type,
5607 -- or a derived type thereof, the component inherited from the
5608 -- generic parent may not be visible in the actual, but the
5609 -- selected component is legal. This case must be handled before
5610 -- trying the object.operation notation to avoid reporting
5611 -- spurious errors, but must be skipped when Is_Prefixed_Call has
5612 -- been set (because that means that this node was resolved to an
5613 -- Object.Operation call when the generic unit was analyzed).
5616 and then not Is_Prefixed_Call
(N
)
5617 and then Is_Tagged_Type
(Prefix_Type
)
5618 and then Try_Selected_Component_In_Instance
(Type_To_Use
)
5622 elsif Try_Object_Operation
(N
) then
5626 -- If the transformation fails, it will be necessary to redo the
5627 -- analysis with all errors enabled, to indicate candidate
5628 -- interpretations and reasons for each failure ???
5632 elsif Is_Private_Type
(Prefix_Type
) then
5634 -- Allow access only to discriminants of the type. If the type has
5635 -- no full view, gigi uses the parent type for the components, so we
5636 -- do the same here.
5638 if No
(Full_View
(Prefix_Type
)) then
5639 Type_To_Use
:= Root_Type
(Base_Type
(Prefix_Type
));
5640 Comp
:= First_Entity
(Type_To_Use
);
5643 while Present
(Comp
) loop
5644 if Chars
(Comp
) = Chars
(Sel
) then
5645 if Ekind
(Comp
) = E_Discriminant
then
5646 Set_Entity_With_Checks
(Sel
, Comp
);
5647 Generate_Reference
(Comp
, Sel
);
5649 Set_Etype
(Sel
, Etype
(Comp
));
5650 Set_Etype
(N
, Etype
(Comp
));
5651 Check_Implicit_Dereference
(N
, Etype
(N
));
5653 if Is_Generic_Type
(Prefix_Type
)
5654 or else Is_Generic_Type
(Root_Type
(Prefix_Type
))
5656 Set_Original_Discriminant
(Sel
, Comp
);
5659 -- Before declaring an error, check whether this is tagged
5660 -- private type and a call to a primitive operation.
5662 elsif Ada_Version
>= Ada_2005
5663 and then Is_Tagged_Type
(Prefix_Type
)
5664 and then Try_Object_Operation
(N
)
5669 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
5670 Error_Msg_NE
("invisible selector& for }", N
, Sel
);
5671 Set_Entity
(Sel
, Any_Id
);
5672 Set_Etype
(N
, Any_Type
);
5681 -- Extension feature: Also support calls with prefixed views for
5682 -- untagged private types.
5684 if Core_Extensions_Allowed
then
5685 if Try_Object_Operation
(N
) then
5690 elsif Is_Concurrent_Type
(Prefix_Type
) then
5692 -- Find visible operation with given name. For a protected type,
5693 -- the possible candidates are discriminants, entries or protected
5694 -- subprograms. For a task type, the set can only include entries or
5695 -- discriminants if the task type is not an enclosing scope. If it
5696 -- is an enclosing scope (e.g. in an inner task) then all entities
5697 -- are visible, but the prefix must denote the enclosing scope, i.e.
5698 -- can only be a direct name or an expanded name.
5700 Set_Etype
(Sel
, Any_Type
);
5701 Hidden_Comp
:= Empty
;
5702 In_Scope
:= In_Open_Scopes
(Prefix_Type
);
5703 Is_Private_Op
:= False;
5705 while Present
(Comp
) loop
5707 -- Do not examine private operations of the type if not within
5710 if Chars
(Comp
) = Chars
(Sel
) then
5711 if Is_Overloadable
(Comp
)
5713 or else Comp
/= First_Private_Entity
(Type_To_Use
))
5715 Add_One_Interp
(Sel
, Comp
, Etype
(Comp
));
5716 if Comp
= First_Private_Entity
(Type_To_Use
) then
5717 Is_Private_Op
:= True;
5720 -- If the prefix is tagged, the correct interpretation may
5721 -- lie in the primitive or class-wide operations of the
5722 -- type. Perform a simple conformance check to determine
5723 -- whether Try_Object_Operation should be invoked even if
5724 -- a visible entity is found.
5726 if Is_Tagged_Type
(Prefix_Type
)
5727 and then Nkind
(Parent
(N
)) in N_Function_Call
5728 | N_Indexed_Component
5729 | N_Procedure_Call_Statement
5730 and then Has_Mode_Conformant_Spec
(Comp
)
5732 Has_Candidate
:= True;
5735 -- Note: a selected component may not denote a component of a
5736 -- protected type (4.1.3(7)).
5738 elsif Ekind
(Comp
) in E_Discriminant | E_Entry_Family
5740 and then not Is_Protected_Type
(Prefix_Type
)
5741 and then Is_Entity_Name
(Name
))
5743 Set_Entity_With_Checks
(Sel
, Comp
);
5744 Generate_Reference
(Comp
, Sel
);
5746 -- The selector is not overloadable, so we have a candidate
5749 Has_Candidate
:= True;
5752 if Ekind
(Comp
) = E_Component
then
5753 Hidden_Comp
:= Comp
;
5759 Set_Etype
(Sel
, Etype
(Comp
));
5760 Set_Etype
(N
, Etype
(Comp
));
5762 if Ekind
(Comp
) = E_Discriminant
then
5763 Set_Original_Discriminant
(Sel
, Comp
);
5768 if Comp
= First_Private_Entity
(Type_To_Use
) then
5769 if Etype
(Sel
) /= Any_Type
then
5771 -- If the first private entity's name matches, then treat
5772 -- it as a private op: needed for the error check for
5773 -- illegal selection of private entities further below.
5775 if Chars
(Comp
) = Chars
(Sel
) then
5776 Is_Private_Op
:= True;
5779 -- We have a candidate, so exit the loop
5784 -- Indicate that subsequent operations are private,
5785 -- for better error reporting.
5787 Is_Private_Op
:= True;
5791 -- Do not examine private operations if not within scope of
5792 -- the synchronized type.
5794 exit when not In_Scope
5796 Comp
= First_Private_Entity
(Base_Type
(Prefix_Type
));
5800 -- If the scope is a current instance, the prefix cannot be an
5801 -- expression of the same type, unless the selector designates a
5802 -- public operation (otherwise that would represent an attempt to
5803 -- reach an internal entity of another synchronized object).
5805 -- This is legal if prefix is an access to such type and there is
5806 -- a dereference, or is a component with a dereferenced prefix.
5807 -- It is also legal if the prefix is a component of a task type,
5808 -- and the selector is one of the task operations.
5811 and then not Is_Entity_Name
(Name
)
5812 and then not Has_Dereference
(Name
)
5814 if Is_Task_Type
(Prefix_Type
)
5815 and then Present
(Entity
(Sel
))
5816 and then Is_Entry
(Entity
(Sel
))
5820 elsif Is_Protected_Type
(Prefix_Type
)
5821 and then Is_Overloadable
(Entity
(Sel
))
5822 and then not Is_Private_Op
5828 ("invalid reference to internal operation of some object of "
5829 & "type &", N
, Type_To_Use
);
5830 Set_Entity
(Sel
, Any_Id
);
5831 Set_Etype
(Sel
, Any_Type
);
5835 -- Another special case: the prefix may denote an object of the type
5836 -- (but not a type) in which case this is an external call and the
5837 -- operation must be public.
5840 and then Is_Object_Reference
(Original_Node
(Prefix
(N
)))
5841 and then Comes_From_Source
(N
)
5842 and then Is_Private_Op
5844 if Present
(Hidden_Comp
) then
5846 ("invalid reference to private component of object of type "
5847 & "&", N
, Type_To_Use
);
5851 ("invalid reference to private operation of some object of "
5852 & "type &", N
, Type_To_Use
);
5855 Set_Entity
(Sel
, Any_Id
);
5856 Set_Etype
(Sel
, Any_Type
);
5860 -- If there is no visible entity with the given name or none of the
5861 -- visible entities are plausible interpretations, check whether
5862 -- there is some other primitive operation with that name.
5864 if Ada_Version
>= Ada_2005
and then Is_Tagged_Type
(Prefix_Type
) then
5865 if (Etype
(N
) = Any_Type
5866 or else not Has_Candidate
)
5867 and then Try_Object_Operation
(N
)
5871 -- If the context is not syntactically a procedure call, it
5872 -- may be a call to a primitive function declared outside of
5873 -- the synchronized type.
5875 -- If the context is a procedure call, there might still be
5876 -- an overloading between an entry and a primitive procedure
5877 -- declared outside of the synchronized type, called in prefix
5878 -- notation. This is harder to disambiguate because in one case
5879 -- the controlling formal is implicit ???
5881 elsif Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
5882 and then Nkind
(Parent
(N
)) /= N_Indexed_Component
5883 and then Try_Object_Operation
(N
)
5888 -- Ada 2012 (AI05-0090-1): If we found a candidate of a call to an
5889 -- entry or procedure of a tagged concurrent type we must check
5890 -- if there are class-wide subprograms covering the primitive. If
5891 -- true then Try_Object_Operation reports the error.
5894 and then Is_Concurrent_Type
(Prefix_Type
)
5895 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
5897 -- Duplicate the call. This is required to avoid problems with
5898 -- the tree transformations performed by Try_Object_Operation.
5899 -- Set properly the parent of the copied call, because it is
5900 -- about to be reanalyzed.
5903 Par
: constant Node_Id
:= New_Copy_Tree
(Parent
(N
));
5906 Set_Parent
(Par
, Parent
(Parent
(N
)));
5908 if Try_Object_Operation
5909 (Sinfo
.Nodes
.Name
(Par
), CW_Test_Only
=> True)
5917 if Etype
(N
) = Any_Type
and then Is_Protected_Type
(Prefix_Type
) then
5919 -- Case of a prefix of a protected type: selector might denote
5920 -- an invisible private component.
5922 Comp
:= First_Private_Entity
(Base_Type
(Prefix_Type
));
5923 while Present
(Comp
) and then Chars
(Comp
) /= Chars
(Sel
) loop
5927 if Present
(Comp
) then
5928 if Is_Single_Concurrent_Object
then
5929 Error_Msg_Node_2
:= Entity
(Name
);
5930 Error_Msg_NE
("invisible selector& for &", N
, Sel
);
5933 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
5934 Error_Msg_NE
("invisible selector& for }", N
, Sel
);
5940 Set_Is_Overloaded
(N
, Is_Overloaded
(Sel
));
5942 -- Extension feature: Also support calls with prefixed views for
5945 elsif Core_Extensions_Allowed
5946 and then Try_Object_Operation
(N
)
5953 Error_Msg_NE
("invalid prefix in selected component&", N
, Sel
);
5956 -- If N still has no type, the component is not defined in the prefix
5958 if Etype
(N
) = Any_Type
then
5960 if Is_Single_Concurrent_Object
then
5961 Error_Msg_Node_2
:= Entity
(Name
);
5962 Error_Msg_NE
("no selector& for&", N
, Sel
);
5964 Check_Misspelled_Selector
(Type_To_Use
, Sel
);
5966 -- If this is a derived formal type, the parent may have different
5967 -- visibility at this point. Try for an inherited component before
5968 -- reporting an error.
5970 elsif Is_Generic_Type
(Prefix_Type
)
5971 and then Ekind
(Prefix_Type
) = E_Record_Type_With_Private
5972 and then Prefix_Type
/= Etype
(Prefix_Type
)
5973 and then Is_Record_Type
(Etype
(Prefix_Type
))
5975 Set_Etype
(Prefix
(N
), Etype
(Prefix_Type
));
5976 Analyze_Selected_Component
(N
);
5979 -- Similarly, if this is the actual for a formal derived type, or
5980 -- a derived type thereof, the component inherited from the generic
5981 -- parent may not be visible in the actual, but the selected
5982 -- component is legal.
5984 elsif In_Instance
and then Is_Tagged_Type
(Prefix_Type
) then
5986 -- Climb up the derivation chain of the generic parent type until
5987 -- we find the proper ancestor type.
5989 if Try_Selected_Component_In_Instance
(Type_To_Use
) then
5992 -- The search above must have eventually succeeded, since the
5993 -- selected component was legal in the generic.
5996 raise Program_Error
;
5999 -- Component not found, specialize error message when appropriate
6002 if Ekind
(Prefix_Type
) = E_Record_Subtype
then
6004 -- Check whether this is a component of the base type which
6005 -- is absent from a statically constrained subtype. This will
6006 -- raise constraint error at run time, but is not a compile-
6007 -- time error. When the selector is illegal for base type as
6008 -- well fall through and generate a compilation error anyway.
6010 Comp
:= First_Component
(Base_Type
(Prefix_Type
));
6011 while Present
(Comp
) loop
6012 if Chars
(Comp
) = Chars
(Sel
)
6013 and then Is_Visible_Component
(Comp
, Sel
)
6015 Set_Entity_With_Checks
(Sel
, Comp
);
6016 Generate_Reference
(Comp
, Sel
);
6017 Set_Etype
(Sel
, Etype
(Comp
));
6018 Set_Etype
(N
, Etype
(Comp
));
6020 -- Emit appropriate message. The node will be replaced
6021 -- by an appropriate raise statement.
6023 -- Note that in GNATprove mode, as with all calls to
6024 -- apply a compile time constraint error, this will be
6025 -- made into an error to simplify the processing of the
6026 -- formal verification backend.
6028 Apply_Compile_Time_Constraint_Error
6029 (N
, "component not present in }??",
6030 CE_Discriminant_Check_Failed
,
6033 GNATprove_Mode
or not In_Instance_Not_Visible
);
6037 Next_Component
(Comp
);
6042 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
6043 Error_Msg_NE
("no selector& for}", N
, Sel
);
6045 -- Add information in the case of an incomplete prefix
6047 if Is_Incomplete_Type
(Type_To_Use
) then
6049 Inc
: constant Entity_Id
:= First_Subtype
(Type_To_Use
);
6052 if From_Limited_With
(Scope
(Type_To_Use
)) then
6054 ("\limited view of& has no components", N
, Inc
);
6058 ("\premature usage of incomplete type&", N
, Inc
);
6060 if Nkind
(Parent
(Inc
)) =
6061 N_Incomplete_Type_Declaration
6063 -- Record location of premature use in entity so that
6064 -- a continuation message is generated when the
6065 -- completion is seen.
6067 Set_Premature_Use
(Parent
(Inc
), N
);
6073 Check_Misspelled_Selector
(Type_To_Use
, Sel
);
6076 Set_Entity
(Sel
, Any_Id
);
6077 Set_Etype
(Sel
, Any_Type
);
6079 end Analyze_Selected_Component
;
6081 ---------------------------
6082 -- Analyze_Short_Circuit --
6083 ---------------------------
6085 procedure Analyze_Short_Circuit
(N
: Node_Id
) is
6086 L
: constant Node_Id
:= Left_Opnd
(N
);
6087 R
: constant Node_Id
:= Right_Opnd
(N
);
6092 Set_Etype
(N
, Any_Type
);
6093 Analyze_Expression
(L
);
6094 Analyze_Expression
(R
);
6096 if not Is_Overloaded
(L
) then
6097 if Root_Type
(Etype
(L
)) = Standard_Boolean
6098 and then Has_Compatible_Type
(R
, Etype
(L
))
6100 Add_One_Interp
(N
, Etype
(L
), Etype
(L
));
6104 Get_First_Interp
(L
, Ind
, It
);
6105 while Present
(It
.Typ
) loop
6106 if Root_Type
(It
.Typ
) = Standard_Boolean
6107 and then Has_Compatible_Type
(R
, It
.Typ
)
6109 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
6112 Get_Next_Interp
(Ind
, It
);
6116 -- Here we have failed to find an interpretation. Clearly we know that
6117 -- it is not the case that both operands can have an interpretation of
6118 -- Boolean, but this is by far the most likely intended interpretation.
6119 -- So we simply resolve both operands as Booleans, and at least one of
6120 -- these resolutions will generate an error message, and we do not need
6121 -- to give another error message on the short circuit operation itself.
6123 if Etype
(N
) = Any_Type
then
6124 Resolve
(L
, Standard_Boolean
);
6125 Resolve
(R
, Standard_Boolean
);
6126 Set_Etype
(N
, Standard_Boolean
);
6130 if Nkind
(L
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
6132 Check_Xtra_Parens_Precedence
(L
);
6135 if Nkind
(R
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
6137 Check_Xtra_Parens_Precedence
(R
);
6140 end Analyze_Short_Circuit
;
6146 procedure Analyze_Slice
(N
: Node_Id
) is
6147 D
: constant Node_Id
:= Discrete_Range
(N
);
6148 P
: constant Node_Id
:= Prefix
(N
);
6149 Array_Type
: Entity_Id
;
6150 Index_Type
: Entity_Id
;
6152 procedure Analyze_Overloaded_Slice
;
6153 -- If the prefix is overloaded, select those interpretations that
6154 -- yield a one-dimensional array type.
6156 ------------------------------
6157 -- Analyze_Overloaded_Slice --
6158 ------------------------------
6160 procedure Analyze_Overloaded_Slice
is
6166 Set_Etype
(N
, Any_Type
);
6168 Get_First_Interp
(P
, I
, It
);
6169 while Present
(It
.Nam
) loop
6172 if Is_Access_Type
(Typ
) then
6173 Typ
:= Designated_Type
(Typ
);
6175 (Warn_On_Dereference
, "?d?implicit dereference", N
);
6178 if Is_Array_Type
(Typ
)
6179 and then Number_Dimensions
(Typ
) = 1
6180 and then Has_Compatible_Type
(D
, Etype
(First_Index
(Typ
)))
6182 Add_One_Interp
(N
, Typ
, Typ
);
6185 Get_Next_Interp
(I
, It
);
6188 if Etype
(N
) = Any_Type
then
6189 Error_Msg_N
("expect array type in prefix of slice", N
);
6191 end Analyze_Overloaded_Slice
;
6193 -- Start of processing for Analyze_Slice
6199 if Is_Overloaded
(P
) then
6200 Analyze_Overloaded_Slice
;
6203 Array_Type
:= Etype
(P
);
6204 Set_Etype
(N
, Any_Type
);
6206 if Is_Access_Type
(Array_Type
) then
6207 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
6208 Array_Type
:= Implicitly_Designated_Type
(Array_Type
);
6211 if not Is_Array_Type
(Array_Type
) then
6212 Wrong_Type
(P
, Any_Array
);
6214 elsif Number_Dimensions
(Array_Type
) > 1 then
6216 ("type is not one-dimensional array in slice prefix", N
);
6219 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
6220 Index_Type
:= Etype
(String_Literal_Low_Bound
(Array_Type
));
6222 Index_Type
:= Etype
(First_Index
(Array_Type
));
6225 if not Has_Compatible_Type
(D
, Index_Type
) then
6226 Wrong_Type
(D
, Index_Type
);
6228 Set_Etype
(N
, Array_Type
);
6234 -----------------------------
6235 -- Analyze_Type_Conversion --
6236 -----------------------------
6238 procedure Analyze_Type_Conversion
(N
: Node_Id
) is
6239 Expr
: constant Node_Id
:= Expression
(N
);
6240 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
6245 -- If Conversion_OK is set, then the Etype is already set, and the only
6246 -- processing required is to analyze the expression. This is used to
6247 -- construct certain "illegal" conversions which are not allowed by Ada
6248 -- semantics, but can be handled by Gigi, see Sinfo for further details.
6250 if Conversion_OK
(N
) then
6255 -- Otherwise full type analysis is required, as well as some semantic
6256 -- checks to make sure the argument of the conversion is appropriate.
6259 Typ
:= Entity
(Mark
);
6262 Analyze_Expression
(Expr
);
6264 Check_Fully_Declared
(Typ
, N
);
6265 Validate_Remote_Type_Type_Conversion
(N
);
6267 -- Only remaining step is validity checks on the argument. These
6268 -- are skipped if the conversion does not come from the source.
6270 if not Comes_From_Source
(N
) then
6273 -- If there was an error in a generic unit, no need to replicate the
6274 -- error message. Conversely, constant-folding in the generic may
6275 -- transform the argument of a conversion into a string literal, which
6276 -- is legal. Therefore the following tests are not performed in an
6277 -- instance. The same applies to an inlined body.
6279 elsif In_Instance
or In_Inlined_Body
then
6282 elsif Nkind
(Expr
) = N_Null
then
6283 Error_Msg_N
("argument of conversion cannot be null", N
);
6284 Error_Msg_N
("\use qualified expression instead", N
);
6285 Set_Etype
(N
, Any_Type
);
6287 elsif Nkind
(Expr
) = N_Aggregate
then
6288 Error_Msg_N
("argument of conversion cannot be aggregate", N
);
6289 Error_Msg_N
("\use qualified expression instead", N
);
6291 elsif Nkind
(Expr
) = N_Allocator
then
6292 Error_Msg_N
("argument of conversion cannot be allocator", N
);
6293 Error_Msg_N
("\use qualified expression instead", N
);
6295 elsif Nkind
(Expr
) = N_String_Literal
then
6296 Error_Msg_N
("argument of conversion cannot be string literal", N
);
6297 Error_Msg_N
("\use qualified expression instead", N
);
6299 elsif Nkind
(Expr
) = N_Character_Literal
then
6300 if Ada_Version
= Ada_83
then
6301 Resolve
(Expr
, Typ
);
6304 ("argument of conversion cannot be character literal", N
);
6305 Error_Msg_N
("\use qualified expression instead", N
);
6308 elsif Nkind
(Expr
) = N_Attribute_Reference
6309 and then Attribute_Name
(Expr
) in Name_Access
6310 | Name_Unchecked_Access
6311 | Name_Unrestricted_Access
6314 ("argument of conversion cannot be access attribute", N
);
6315 Error_Msg_N
("\use qualified expression instead", N
);
6318 -- A formal parameter of a specific tagged type whose related subprogram
6319 -- is subject to pragma Extensions_Visible with value "False" cannot
6320 -- appear in a class-wide conversion (SPARK RM 6.1.7(3)). Do not check
6321 -- internally generated expressions.
6323 if Is_Class_Wide_Type
(Typ
)
6324 and then Comes_From_Source
(Expr
)
6325 and then Is_EVF_Expression
(Expr
)
6328 ("formal parameter cannot be converted to class-wide type when "
6329 & "Extensions_Visible is False", Expr
);
6331 end Analyze_Type_Conversion
;
6333 ----------------------
6334 -- Analyze_Unary_Op --
6335 ----------------------
6337 procedure Analyze_Unary_Op
(N
: Node_Id
) is
6338 R
: constant Node_Id
:= Right_Opnd
(N
);
6343 Set_Etype
(N
, Any_Type
);
6344 Candidate_Type
:= Empty
;
6346 Analyze_Expression
(R
);
6348 -- If the entity is already set, the node is the instantiation of a
6349 -- generic node with a non-local reference, or was manufactured by a
6350 -- call to Make_Op_xxx. In either case the entity is known to be valid,
6351 -- and we do not need to collect interpretations, instead we just get
6352 -- the single possible interpretation.
6354 if Present
(Entity
(N
)) then
6355 Op_Id
:= Entity
(N
);
6357 if Ekind
(Op_Id
) = E_Operator
then
6358 Find_Unary_Types
(R
, Op_Id
, N
);
6360 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
6364 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
6365 while Present
(Op_Id
) loop
6366 if Ekind
(Op_Id
) = E_Operator
then
6367 if No
(Next_Entity
(First_Entity
(Op_Id
))) then
6368 Find_Unary_Types
(R
, Op_Id
, N
);
6371 elsif Is_Overloadable
(Op_Id
) then
6372 Analyze_User_Defined_Unary_Op
(N
, Op_Id
);
6375 Op_Id
:= Homonym
(Op_Id
);
6380 end Analyze_Unary_Op
;
6382 ----------------------------------
6383 -- Analyze_Unchecked_Expression --
6384 ----------------------------------
6386 procedure Analyze_Unchecked_Expression
(N
: Node_Id
) is
6387 Expr
: constant Node_Id
:= Expression
(N
);
6390 Analyze
(Expr
, Suppress
=> All_Checks
);
6391 Set_Etype
(N
, Etype
(Expr
));
6392 Save_Interps
(Expr
, N
);
6393 end Analyze_Unchecked_Expression
;
6395 ---------------------------------------
6396 -- Analyze_Unchecked_Type_Conversion --
6397 ---------------------------------------
6399 procedure Analyze_Unchecked_Type_Conversion
(N
: Node_Id
) is
6400 Expr
: constant Node_Id
:= Expression
(N
);
6401 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
6405 Set_Etype
(N
, Entity
(Mark
));
6406 Analyze_Expression
(Expr
);
6407 end Analyze_Unchecked_Type_Conversion
;
6409 ------------------------------------
6410 -- Analyze_User_Defined_Binary_Op --
6411 ------------------------------------
6413 procedure Analyze_User_Defined_Binary_Op
6415 Op_Id
: Entity_Id
) is
6418 F1
: constant Entity_Id
:= First_Formal
(Op_Id
);
6419 F2
: constant Entity_Id
:= Next_Formal
(F1
);
6422 -- Verify that Op_Id is a visible binary function. Note that since
6423 -- we know Op_Id is overloaded, potentially use visible means use
6424 -- visible for sure (RM 9.4(11)). Be prepared for previous errors.
6426 if Ekind
(Op_Id
) = E_Function
6427 and then Present
(F2
)
6428 and then (Is_Immediately_Visible
(Op_Id
)
6429 or else Is_Potentially_Use_Visible
(Op_Id
))
6430 and then (Has_Compatible_Type
(Left_Opnd
(N
), Etype
(F1
))
6431 or else Etype
(F1
) = Any_Type
)
6432 and then (Has_Compatible_Type
(Right_Opnd
(N
), Etype
(F2
))
6433 or else Etype
(F2
) = Any_Type
)
6435 Add_One_Interp
(N
, Op_Id
, Base_Type
(Etype
(Op_Id
)));
6437 -- If the operands are overloaded, indicate that the current
6438 -- type is a viable candidate. This is redundant in most cases,
6439 -- but for equality and comparison operators where the context
6440 -- does not impose a type on the operands, setting the proper
6441 -- type is necessary to avoid subsequent ambiguities during
6442 -- resolution, when both user-defined and predefined operators
6443 -- may be candidates.
6445 if Is_Overloaded
(Left_Opnd
(N
)) then
6446 Set_Etype
(Left_Opnd
(N
), Etype
(F1
));
6449 if Is_Overloaded
(Right_Opnd
(N
)) then
6450 Set_Etype
(Right_Opnd
(N
), Etype
(F2
));
6453 if Debug_Flag_E
then
6454 Write_Str
("user defined operator ");
6455 Write_Name
(Chars
(Op_Id
));
6456 Write_Str
(" on node ");
6457 Write_Int
(Int
(N
));
6462 end Analyze_User_Defined_Binary_Op
;
6464 -----------------------------------
6465 -- Analyze_User_Defined_Unary_Op --
6466 -----------------------------------
6468 procedure Analyze_User_Defined_Unary_Op
6473 -- Only do analysis if the operator Comes_From_Source, since otherwise
6474 -- the operator was generated by the expander, and all such operators
6475 -- always refer to the operators in package Standard.
6477 if Comes_From_Source
(N
) then
6479 F
: constant Entity_Id
:= First_Formal
(Op_Id
);
6482 -- Verify that Op_Id is a visible unary function. Note that since
6483 -- we know Op_Id is overloaded, potentially use visible means use
6484 -- visible for sure (RM 9.4(11)).
6486 if Ekind
(Op_Id
) = E_Function
6487 and then No
(Next_Formal
(F
))
6488 and then (Is_Immediately_Visible
(Op_Id
)
6489 or else Is_Potentially_Use_Visible
(Op_Id
))
6490 and then Has_Compatible_Type
(Right_Opnd
(N
), Etype
(F
))
6492 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
6496 end Analyze_User_Defined_Unary_Op
;
6498 ---------------------------
6499 -- Check_Arithmetic_Pair --
6500 ---------------------------
6502 procedure Check_Arithmetic_Pair
6503 (T1
, T2
: Entity_Id
;
6507 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
6509 function Has_Fixed_Op
(Typ
: Entity_Id
; Op
: Entity_Id
) return Boolean;
6510 -- Check whether the fixed-point type Typ has a user-defined operator
6511 -- (multiplication or division) that should hide the corresponding
6512 -- predefined operator. Used to implement Ada 2005 AI-264, to make
6513 -- such operators more visible and therefore useful.
6515 -- If the name of the operation is an expanded name with prefix
6516 -- Standard, the predefined universal fixed operator is available,
6517 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
6523 function Has_Fixed_Op
(Typ
: Entity_Id
; Op
: Entity_Id
) return Boolean is
6524 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
6530 -- If the universal_fixed operation is given explicitly the rule
6531 -- concerning primitive operations of the type do not apply.
6533 if Nkind
(N
) = N_Function_Call
6534 and then Nkind
(Name
(N
)) = N_Expanded_Name
6535 and then Entity
(Prefix
(Name
(N
))) = Standard_Standard
6540 -- The operation is treated as primitive if it is declared in the
6541 -- same scope as the type, and therefore on the same entity chain.
6543 Ent
:= Next_Entity
(Typ
);
6544 while Present
(Ent
) loop
6545 if Chars
(Ent
) = Chars
(Op
) then
6546 F1
:= First_Formal
(Ent
);
6547 F2
:= Next_Formal
(F1
);
6549 -- The operation counts as primitive if either operand or
6550 -- result are of the given base type, and both operands are
6551 -- fixed point types.
6553 if (Base_Type
(Etype
(F1
)) = Bas
6554 and then Is_Fixed_Point_Type
(Etype
(F2
)))
6557 (Base_Type
(Etype
(F2
)) = Bas
6558 and then Is_Fixed_Point_Type
(Etype
(F1
)))
6561 (Base_Type
(Etype
(Ent
)) = Bas
6562 and then Is_Fixed_Point_Type
(Etype
(F1
))
6563 and then Is_Fixed_Point_Type
(Etype
(F2
)))
6575 -- Start of processing for Check_Arithmetic_Pair
6578 if Op_Name
in Name_Op_Add | Name_Op_Subtract
then
6579 if Is_Numeric_Type
(T1
)
6580 and then Is_Numeric_Type
(T2
)
6581 and then (Covers
(T1
=> T1
, T2
=> T2
)
6583 Covers
(T1
=> T2
, T2
=> T1
))
6585 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6588 elsif Op_Name
in Name_Op_Multiply | Name_Op_Divide
then
6589 if Is_Fixed_Point_Type
(T1
)
6590 and then (Is_Fixed_Point_Type
(T2
) or else T2
= Universal_Real
)
6592 -- Add one interpretation with universal fixed result
6594 if not Has_Fixed_Op
(T1
, Op_Id
)
6595 or else Nkind
(Parent
(N
)) = N_Type_Conversion
6597 Add_One_Interp
(N
, Op_Id
, Universal_Fixed
);
6600 elsif Is_Fixed_Point_Type
(T2
)
6601 and then T1
= Universal_Real
6603 (not Has_Fixed_Op
(T1
, Op_Id
)
6604 or else Nkind
(Parent
(N
)) = N_Type_Conversion
)
6606 Add_One_Interp
(N
, Op_Id
, Universal_Fixed
);
6608 elsif Is_Numeric_Type
(T1
)
6609 and then Is_Numeric_Type
(T2
)
6610 and then (Covers
(T1
=> T1
, T2
=> T2
)
6612 Covers
(T1
=> T2
, T2
=> T1
))
6614 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6616 elsif Is_Fixed_Point_Type
(T1
)
6617 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6618 or else T2
= Universal_Integer
)
6620 Add_One_Interp
(N
, Op_Id
, T1
);
6622 elsif T2
= Universal_Real
6623 and then Base_Type
(T1
) = Base_Type
(Standard_Integer
)
6624 and then Op_Name
= Name_Op_Multiply
6626 Add_One_Interp
(N
, Op_Id
, Any_Fixed
);
6628 elsif T1
= Universal_Real
6629 and then Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6631 Add_One_Interp
(N
, Op_Id
, Any_Fixed
);
6633 elsif Is_Fixed_Point_Type
(T2
)
6634 and then (Base_Type
(T1
) = Base_Type
(Standard_Integer
)
6635 or else T1
= Universal_Integer
)
6636 and then Op_Name
= Name_Op_Multiply
6638 Add_One_Interp
(N
, Op_Id
, T2
);
6640 elsif T1
= Universal_Real
and then T2
= Universal_Integer
then
6641 Add_One_Interp
(N
, Op_Id
, T1
);
6643 elsif T2
= Universal_Real
6644 and then T1
= Universal_Integer
6645 and then Op_Name
= Name_Op_Multiply
6647 Add_One_Interp
(N
, Op_Id
, T2
);
6650 elsif Op_Name
= Name_Op_Mod
or else Op_Name
= Name_Op_Rem
then
6652 if Is_Integer_Type
(T1
)
6653 and then (Covers
(T1
=> T1
, T2
=> T2
)
6655 Covers
(T1
=> T2
, T2
=> T1
))
6657 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6660 elsif Op_Name
= Name_Op_Expon
then
6661 if Is_Numeric_Type
(T1
)
6662 and then not Is_Fixed_Point_Type
(T1
)
6663 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6664 or else T2
= Universal_Integer
)
6666 Add_One_Interp
(N
, Op_Id
, Base_Type
(T1
));
6669 else pragma Assert
(Nkind
(N
) in N_Op_Shift
);
6671 -- If not one of the predefined operators, the node may be one
6672 -- of the intrinsic functions. Its kind is always specific, and
6673 -- we can use it directly, rather than the name of the operation.
6675 if Is_Integer_Type
(T1
)
6676 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6677 or else T2
= Universal_Integer
)
6679 Add_One_Interp
(N
, Op_Id
, Base_Type
(T1
));
6682 end Check_Arithmetic_Pair
;
6684 -------------------------------
6685 -- Check_Misspelled_Selector --
6686 -------------------------------
6688 procedure Check_Misspelled_Selector
6689 (Prefix
: Entity_Id
;
6692 Max_Suggestions
: constant := 2;
6693 Nr_Of_Suggestions
: Natural := 0;
6695 Suggestion_1
: Entity_Id
:= Empty
;
6696 Suggestion_2
: Entity_Id
:= Empty
;
6701 -- All the components of the prefix of selector Sel are matched against
6702 -- Sel and a count is maintained of possible misspellings. When at
6703 -- the end of the analysis there are one or two (not more) possible
6704 -- misspellings, these misspellings will be suggested as possible
6707 if not (Is_Private_Type
(Prefix
) or else Is_Record_Type
(Prefix
)) then
6709 -- Concurrent types should be handled as well ???
6714 Comp
:= First_Entity
(Prefix
);
6715 while Nr_Of_Suggestions
<= Max_Suggestions
and then Present
(Comp
) loop
6716 if Is_Visible_Component
(Comp
, Sel
) then
6717 if Is_Bad_Spelling_Of
(Chars
(Comp
), Chars
(Sel
)) then
6718 Nr_Of_Suggestions
:= Nr_Of_Suggestions
+ 1;
6720 case Nr_Of_Suggestions
is
6721 when 1 => Suggestion_1
:= Comp
;
6722 when 2 => Suggestion_2
:= Comp
;
6723 when others => null;
6731 -- Report at most two suggestions
6733 if Nr_Of_Suggestions
= 1 then
6734 Error_Msg_NE
-- CODEFIX
6735 ("\possible misspelling of&", Sel
, Suggestion_1
);
6737 elsif Nr_Of_Suggestions
= 2 then
6738 Error_Msg_Node_2
:= Suggestion_2
;
6739 Error_Msg_NE
-- CODEFIX
6740 ("\possible misspelling of& or&", Sel
, Suggestion_1
);
6742 end Check_Misspelled_Selector
;
6748 procedure Diagnose_Call
(N
: Node_Id
; Nam
: Node_Id
) is
6754 Num_Actuals
: Natural;
6755 Num_Interps
: Natural;
6756 Void_Interp_Seen
: Boolean := False;
6759 pragma Warnings
(Off
, Boolean);
6763 Actual
:= First_Actual
(N
);
6765 while Present
(Actual
) loop
6766 -- Ada 2005 (AI-50217): Post an error in case of premature
6767 -- usage of an entity from the limited view.
6769 if not Analyzed
(Etype
(Actual
))
6770 and then From_Limited_With
(Etype
(Actual
))
6771 and then Ada_Version
>= Ada_2005
6773 Error_Msg_Qual_Level
:= 1;
6775 ("missing with_clause for scope of imported type&",
6776 Actual
, Etype
(Actual
));
6777 Error_Msg_Qual_Level
:= 0;
6780 Num_Actuals
:= Num_Actuals
+ 1;
6781 Next_Actual
(Actual
);
6784 -- Before listing the possible candidates, check whether this is
6785 -- a prefix of a selected component that has been rewritten as a
6786 -- parameterless function call because there is a callable candidate
6787 -- interpretation. If there is a hidden package in the list of homonyms
6788 -- of the function name (bad programming style in any case) suggest that
6789 -- this is the intended entity.
6791 if No
(Parameter_Associations
(N
))
6792 and then Nkind
(Parent
(N
)) = N_Selected_Component
6793 and then Nkind
(Parent
(Parent
(N
))) in N_Declaration
6794 and then Is_Overloaded
(Nam
)
6800 Ent
:= Current_Entity
(Nam
);
6801 while Present
(Ent
) loop
6802 if Ekind
(Ent
) = E_Package
then
6804 ("no legal interpretations as function call,!", Nam
);
6805 Error_Msg_NE
("\package& is not visible", N
, Ent
);
6807 Rewrite
(Parent
(N
),
6808 New_Occurrence_Of
(Any_Type
, Sloc
(N
)));
6812 Ent
:= Homonym
(Ent
);
6817 -- If this is a call to an operation of a concurrent type, the failed
6818 -- interpretations have been removed from the name. Recover them now
6819 -- in order to provide full diagnostics.
6821 if Nkind
(Parent
(Nam
)) = N_Selected_Component
then
6822 Set_Entity
(Nam
, Empty
);
6823 New_Nam
:= New_Copy_Tree
(Parent
(Nam
));
6824 Set_Is_Overloaded
(New_Nam
, False);
6825 Set_Is_Overloaded
(Selector_Name
(New_Nam
), False);
6826 Set_Parent
(New_Nam
, Parent
(Parent
(Nam
)));
6827 Analyze_Selected_Component
(New_Nam
);
6828 Get_First_Interp
(Selector_Name
(New_Nam
), X
, It
);
6830 Get_First_Interp
(Nam
, X
, It
);
6833 -- If the number of actuals is 2, then remove interpretations involving
6834 -- a unary "+" operator as they might yield confusing errors downstream.
6837 and then Nkind
(Parent
(Nam
)) /= N_Selected_Component
6841 while Present
(It
.Nam
) loop
6842 if Ekind
(It
.Nam
) = E_Operator
6843 and then Chars
(It
.Nam
) = Name_Op_Add
6844 and then (No
(First_Formal
(It
.Nam
))
6845 or else No
(Next_Formal
(First_Formal
(It
.Nam
))))
6849 Num_Interps
:= Num_Interps
+ 1;
6852 Get_Next_Interp
(X
, It
);
6855 if Num_Interps
= 0 then
6856 Error_Msg_N
("!too many arguments in call to&", Nam
);
6860 Get_First_Interp
(Nam
, X
, It
);
6863 Num_Interps
:= 2; -- at least
6866 -- Analyze each candidate call again with full error reporting for each
6868 if Num_Interps
> 1 then
6869 Error_Msg_N
("!no candidate interpretations match the actuals:", Nam
);
6872 Err_Mode
:= All_Errors_Mode
;
6873 All_Errors_Mode
:= True;
6875 while Present
(It
.Nam
) loop
6876 if Etype
(It
.Nam
) = Standard_Void_Type
then
6877 Void_Interp_Seen
:= True;
6880 Analyze_One_Call
(N
, It
.Nam
, True, Success
);
6881 Get_Next_Interp
(X
, It
);
6884 if Nkind
(N
) = N_Function_Call
then
6885 Get_First_Interp
(Nam
, X
, It
);
6888 and then Ekind
(Entity
(Name
(N
))) = E_Function
6889 and then Present
(Homonym
(Entity
(Name
(N
))))
6891 -- A name may appear overloaded if it has a homonym, even if that
6892 -- homonym is non-overloadable, in which case the overload list is
6893 -- in fact empty. This specialized case deserves a special message
6894 -- if the homonym is a child package.
6897 Nam
: constant Node_Id
:= Name
(N
);
6898 H
: constant Entity_Id
:= Homonym
(Entity
(Nam
));
6901 if Ekind
(H
) = E_Package
and then Is_Child_Unit
(H
) then
6902 Error_Msg_Qual_Level
:= 2;
6903 Error_Msg_NE
("if an entity in package& is meant, ", Nam
, H
);
6904 Error_Msg_NE
("\use a fully qualified name", Nam
, H
);
6905 Error_Msg_Qual_Level
:= 0;
6910 while Present
(It
.Nam
) loop
6911 if Ekind
(It
.Nam
) in E_Function | E_Operator
then
6914 Get_Next_Interp
(X
, It
);
6918 -- If all interpretations are procedures, this deserves a more
6919 -- precise message. Ditto if this appears as the prefix of a
6920 -- selected component, which may be a lexical error.
6923 ("\context requires function call, found procedure name", Nam
);
6925 if Nkind
(Parent
(N
)) = N_Selected_Component
6926 and then N
= Prefix
(Parent
(N
))
6928 Error_Msg_N
-- CODEFIX
6929 ("\period should probably be semicolon", Parent
(N
));
6933 elsif Nkind
(N
) = N_Procedure_Call_Statement
6934 and then not Void_Interp_Seen
6936 Error_Msg_N
("\function name found in procedure call", Nam
);
6939 All_Errors_Mode
:= Err_Mode
;
6942 ---------------------------
6943 -- Find_Arithmetic_Types --
6944 ---------------------------
6946 procedure Find_Arithmetic_Types
6951 procedure Check_Right_Argument
(T
: Entity_Id
);
6952 -- Check right operand of operator
6954 --------------------------
6955 -- Check_Right_Argument --
6956 --------------------------
6958 procedure Check_Right_Argument
(T
: Entity_Id
) is
6963 if not Is_Overloaded
(R
) then
6964 Check_Arithmetic_Pair
(T
, Etype
(R
), Op_Id
, N
);
6967 Get_First_Interp
(R
, I
, It
);
6968 while Present
(It
.Typ
) loop
6969 Check_Arithmetic_Pair
(T
, It
.Typ
, Op_Id
, N
);
6970 Get_Next_Interp
(I
, It
);
6973 end Check_Right_Argument
;
6980 -- Start of processing for Find_Arithmetic_Types
6983 if not Is_Overloaded
(L
) then
6984 Check_Right_Argument
(Etype
(L
));
6987 Get_First_Interp
(L
, I
, It
);
6988 while Present
(It
.Typ
) loop
6989 Check_Right_Argument
(It
.Typ
);
6990 Get_Next_Interp
(I
, It
);
6993 end Find_Arithmetic_Types
;
6995 ------------------------
6996 -- Find_Boolean_Types --
6997 ------------------------
6999 procedure Find_Boolean_Types
7004 procedure Check_Boolean_Pair
(T1
, T2
: Entity_Id
);
7005 -- Check operand pair of operator
7007 procedure Check_Right_Argument
(T
: Entity_Id
);
7008 -- Check right operand of operator
7010 ------------------------
7011 -- Check_Boolean_Pair --
7012 ------------------------
7014 procedure Check_Boolean_Pair
(T1
, T2
: Entity_Id
) is
7018 if Valid_Boolean_Arg
(T1
)
7019 and then Valid_Boolean_Arg
(T2
)
7020 and then (Covers
(T1
=> T1
, T2
=> T2
)
7021 or else Covers
(T1
=> T2
, T2
=> T1
))
7023 T
:= Specific_Type
(T1
, T2
);
7025 if T
= Universal_Integer
then
7029 Add_One_Interp
(N
, Op_Id
, T
);
7031 end Check_Boolean_Pair
;
7033 --------------------------
7034 -- Check_Right_Argument --
7035 --------------------------
7037 procedure Check_Right_Argument
(T
: Entity_Id
) is
7042 -- Defend against previous error
7044 if Nkind
(R
) = N_Error
then
7047 elsif not Is_Overloaded
(R
) then
7048 Check_Boolean_Pair
(T
, Etype
(R
));
7051 Get_First_Interp
(R
, I
, It
);
7052 while Present
(It
.Typ
) loop
7053 Check_Boolean_Pair
(T
, It
.Typ
);
7054 Get_Next_Interp
(I
, It
);
7057 end Check_Right_Argument
;
7064 -- Start of processing for Find_Boolean_Types
7067 if not Is_Overloaded
(L
) then
7068 Check_Right_Argument
(Etype
(L
));
7071 Get_First_Interp
(L
, I
, It
);
7072 while Present
(It
.Typ
) loop
7073 Check_Right_Argument
(It
.Typ
);
7074 Get_Next_Interp
(I
, It
);
7077 end Find_Boolean_Types
;
7079 ------------------------------------
7080 -- Find_Comparison_Equality_Types --
7081 ------------------------------------
7083 -- The context of the operator plays no role in resolving the operands,
7084 -- so that if there is more than one interpretation of the operands that
7085 -- is compatible with the comparison or equality, then the operation is
7086 -- ambiguous, but this cannot be reported at this point because there is
7087 -- no guarantee that the operation will be resolved to this operator yet.
7089 procedure Find_Comparison_Equality_Types
7094 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
7095 Op_Typ
: Entity_Id
renames Standard_Boolean
;
7097 function Try_Left_Interp
(T
: Entity_Id
) return Entity_Id
;
7098 -- Try an interpretation of the left operand with type T. Return the
7099 -- type of the interpretation of the right operand making up a valid
7100 -- operand pair, or else Any_Type if the right operand is ambiguous,
7101 -- otherwise Empty if no such pair exists.
7103 function Is_Valid_Comparison_Type
(T
: Entity_Id
) return Boolean;
7104 -- Return true if T is a valid comparison type
7106 function Is_Valid_Equality_Type
7108 Anon_Access
: Boolean) return Boolean;
7109 -- Return true if T is a valid equality type
7111 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean;
7112 -- Return true if T1 and T2 constitute a valid pair of operand types for
7113 -- L and R respectively.
7115 ---------------------
7116 -- Try_Left_Interp --
7117 ---------------------
7119 function Try_Left_Interp
(T
: Entity_Id
) return Entity_Id
is
7123 Valid_I
: Interp_Index
;
7126 -- Defend against previous error
7128 if Nkind
(R
) = N_Error
then
7131 -- Loop through the interpretations of the right operand
7133 elsif not Is_Overloaded
(R
) then
7134 if Is_Valid_Pair
(T
, Etype
(R
)) then
7142 Get_First_Interp
(R
, I
, It
);
7143 while Present
(It
.Typ
) loop
7144 if Is_Valid_Pair
(T
, It
.Typ
) then
7145 -- If several interpretations are possible, disambiguate
7148 and then Base_Type
(It
.Typ
) /= Base_Type
(R_Typ
)
7150 It
:= Disambiguate
(R
, Valid_I
, I
, Any_Type
);
7152 if It
= No_Interp
then
7164 Get_Next_Interp
(I
, It
);
7167 if Present
(R_Typ
) then
7173 end Try_Left_Interp
;
7175 ------------------------------
7176 -- Is_Valid_Comparison_Type --
7177 ------------------------------
7179 function Is_Valid_Comparison_Type
(T
: Entity_Id
) return Boolean is
7181 -- The operation must be performed in a context where the operators
7182 -- of the base type are visible.
7184 if Is_Visible_Operator
(N
, Base_Type
(T
)) then
7187 -- Save candidate type for subsequent error message, if any
7190 if Valid_Comparison_Arg
(T
) then
7191 Candidate_Type
:= T
;
7197 -- Defer to the common implementation for the rest
7199 return Valid_Comparison_Arg
(T
);
7200 end Is_Valid_Comparison_Type
;
7202 ----------------------------
7203 -- Is_Valid_Equality_Type --
7204 ----------------------------
7206 function Is_Valid_Equality_Type
7208 Anon_Access
: Boolean) return Boolean
7211 -- The operation must be performed in a context where the operators
7212 -- of the base type are visible. Deal with special types used with
7213 -- access types before type resolution is done.
7215 if Ekind
(T
) = E_Access_Attribute_Type
7216 or else (Ekind
(T
) in E_Access_Subprogram_Type
7217 | E_Access_Protected_Subprogram_Type
7219 Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
)
7220 or else Is_Visible_Operator
(N
, Base_Type
(T
))
7224 -- AI95-0230: Keep restriction imposed by Ada 83 and 95, do not allow
7225 -- anonymous access types in universal_access equality operators.
7227 elsif Anon_Access
then
7228 if Ada_Version
< Ada_2005
then
7232 -- Save candidate type for subsequent error message, if any
7235 if Valid_Equality_Arg
(T
) then
7236 Candidate_Type
:= T
;
7242 -- For the use of a "/=" operator on a tagged type, several possible
7243 -- interpretations of equality need to be considered, we don't want
7244 -- the default inequality declared in Standard to be chosen, and the
7245 -- "/=" operator will be rewritten as a negation of "=" (see the end
7246 -- of Analyze_Comparison_Equality_Op). This ensures the rewriting
7247 -- occurs during analysis rather than being delayed until expansion.
7248 -- Note that, if the node is N_Op_Ne but Op_Id is Name_Op_Eq, then we
7249 -- still proceed with the interpretation, because this indicates
7250 -- the aforementioned rewriting case where the interpretation to be
7251 -- considered is actually that of the "=" operator.
7253 if Nkind
(N
) = N_Op_Ne
7254 and then Op_Name
/= Name_Op_Eq
7255 and then Is_Tagged_Type
(T
)
7259 -- Defer to the common implementation for the rest
7262 return Valid_Equality_Arg
(T
);
7264 end Is_Valid_Equality_Type
;
7270 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean is
7272 if Op_Name
= Name_Op_Eq
or else Op_Name
= Name_Op_Ne
then
7274 Anon_Access
: constant Boolean :=
7275 Is_Anonymous_Access_Type
(T1
)
7276 or else Is_Anonymous_Access_Type
(T2
);
7277 -- RM 4.5.2(9.1/2): At least one of the operands of an equality
7278 -- operator for universal_access shall be of specific anonymous
7282 if not Is_Valid_Equality_Type
(T1
, Anon_Access
)
7283 or else not Is_Valid_Equality_Type
(T2
, Anon_Access
)
7290 if not Is_Valid_Comparison_Type
(T1
)
7291 or else not Is_Valid_Comparison_Type
(T2
)
7297 return Covers
(T1
=> T1
, T2
=> T2
)
7298 or else Covers
(T1
=> T2
, T2
=> T1
)
7299 or else Is_User_Defined_Literal
(L
, T2
)
7300 or else Is_User_Defined_Literal
(R
, T1
);
7310 Valid_I
: Interp_Index
;
7312 -- Start of processing for Find_Comparison_Equality_Types
7315 -- Loop through the interpretations of the left operand
7317 if not Is_Overloaded
(L
) then
7318 T
:= Try_Left_Interp
(Etype
(L
));
7322 Add_One_Interp
(N
, Op_Id
, Op_Typ
, Find_Unique_Type
(L
, R
));
7330 Get_First_Interp
(L
, I
, It
);
7331 while Present
(It
.Typ
) loop
7332 T
:= Try_Left_Interp
(It
.Typ
);
7335 -- If several interpretations are possible, disambiguate
7338 and then Base_Type
(It
.Typ
) /= Base_Type
(L_Typ
)
7340 It
:= Disambiguate
(L
, Valid_I
, I
, Any_Type
);
7342 if It
= No_Interp
then
7356 Get_Next_Interp
(I
, It
);
7359 if Present
(L_Typ
) then
7360 Set_Etype
(L
, L_Typ
);
7361 Set_Etype
(R
, R_Typ
);
7362 Add_One_Interp
(N
, Op_Id
, Op_Typ
, Find_Unique_Type
(L
, R
));
7365 end Find_Comparison_Equality_Types
;
7367 ------------------------------
7368 -- Find_Concatenation_Types --
7369 ------------------------------
7371 procedure Find_Concatenation_Types
7376 Is_String
: constant Boolean := Nkind
(L
) = N_String_Literal
7378 Nkind
(R
) = N_String_Literal
;
7379 Op_Type
: constant Entity_Id
:= Etype
(Op_Id
);
7382 if Is_Array_Type
(Op_Type
)
7384 -- Small but very effective optimization: if at least one operand is a
7385 -- string literal, then the type of the operator must be either array
7386 -- of characters or array of strings.
7388 and then (not Is_String
7390 Is_Character_Type
(Component_Type
(Op_Type
))
7392 Is_String_Type
(Component_Type
(Op_Type
)))
7394 and then not Is_Limited_Type
(Op_Type
)
7396 and then (Has_Compatible_Type
(L
, Op_Type
)
7398 Has_Compatible_Type
(L
, Component_Type
(Op_Type
)))
7400 and then (Has_Compatible_Type
(R
, Op_Type
)
7402 Has_Compatible_Type
(R
, Component_Type
(Op_Type
)))
7404 Add_One_Interp
(N
, Op_Id
, Op_Type
);
7406 end Find_Concatenation_Types
;
7408 -------------------------
7409 -- Find_Negation_Types --
7410 -------------------------
7412 procedure Find_Negation_Types
7417 Index
: Interp_Index
;
7421 if not Is_Overloaded
(R
) then
7422 if Etype
(R
) = Universal_Integer
then
7423 Add_One_Interp
(N
, Op_Id
, Any_Modular
);
7424 elsif Valid_Boolean_Arg
(Etype
(R
)) then
7425 Add_One_Interp
(N
, Op_Id
, Etype
(R
));
7429 Get_First_Interp
(R
, Index
, It
);
7430 while Present
(It
.Typ
) loop
7431 if Valid_Boolean_Arg
(It
.Typ
) then
7432 Add_One_Interp
(N
, Op_Id
, It
.Typ
);
7435 Get_Next_Interp
(Index
, It
);
7438 end Find_Negation_Types
;
7440 ------------------------------
7441 -- Find_Primitive_Operation --
7442 ------------------------------
7444 function Find_Primitive_Operation
(N
: Node_Id
) return Boolean is
7445 Obj
: constant Node_Id
:= Prefix
(N
);
7446 Op
: constant Node_Id
:= Selector_Name
(N
);
7453 Set_Etype
(Op
, Any_Type
);
7455 if Is_Access_Type
(Etype
(Obj
)) then
7456 Typ
:= Designated_Type
(Etype
(Obj
));
7461 if Is_Class_Wide_Type
(Typ
) then
7462 Typ
:= Root_Type
(Typ
);
7465 Prims
:= Primitive_Operations
(Typ
);
7467 Prim
:= First_Elmt
(Prims
);
7468 while Present
(Prim
) loop
7469 if Chars
(Node
(Prim
)) = Chars
(Op
) then
7470 Add_One_Interp
(Op
, Node
(Prim
), Etype
(Node
(Prim
)));
7471 Set_Etype
(N
, Etype
(Node
(Prim
)));
7477 -- Now look for class-wide operations of the type or any of its
7478 -- ancestors by iterating over the homonyms of the selector.
7481 Cls_Type
: constant Entity_Id
:= Class_Wide_Type
(Typ
);
7485 Hom
:= Current_Entity
(Op
);
7486 while Present
(Hom
) loop
7487 if (Ekind
(Hom
) = E_Procedure
7489 Ekind
(Hom
) = E_Function
)
7490 and then Scope
(Hom
) = Scope
(Typ
)
7491 and then Present
(First_Formal
(Hom
))
7493 (Base_Type
(Etype
(First_Formal
(Hom
))) = Cls_Type
7495 (Is_Access_Type
(Etype
(First_Formal
(Hom
)))
7497 Ekind
(Etype
(First_Formal
(Hom
))) =
7498 E_Anonymous_Access_Type
7501 (Designated_Type
(Etype
(First_Formal
(Hom
)))) =
7504 Add_One_Interp
(Op
, Hom
, Etype
(Hom
));
7505 Set_Etype
(N
, Etype
(Hom
));
7508 Hom
:= Homonym
(Hom
);
7512 return Etype
(Op
) /= Any_Type
;
7513 end Find_Primitive_Operation
;
7515 ----------------------
7516 -- Find_Unary_Types --
7517 ----------------------
7519 procedure Find_Unary_Types
7524 Index
: Interp_Index
;
7528 if not Is_Overloaded
(R
) then
7529 if Is_Numeric_Type
(Etype
(R
)) then
7531 -- In an instance a generic actual may be a numeric type even if
7532 -- the formal in the generic unit was not. In that case, the
7533 -- predefined operator was not a possible interpretation in the
7534 -- generic, and cannot be one in the instance, unless the operator
7535 -- is an actual of an instance.
7539 not Is_Numeric_Type
(Corresponding_Generic_Type
(Etype
(R
)))
7543 Add_One_Interp
(N
, Op_Id
, Base_Type
(Etype
(R
)));
7548 Get_First_Interp
(R
, Index
, It
);
7549 while Present
(It
.Typ
) loop
7550 if Is_Numeric_Type
(It
.Typ
) then
7554 (Corresponding_Generic_Type
(Etype
(It
.Typ
)))
7559 Add_One_Interp
(N
, Op_Id
, Base_Type
(It
.Typ
));
7563 Get_Next_Interp
(Index
, It
);
7566 end Find_Unary_Types
;
7572 function Junk_Operand
(N
: Node_Id
) return Boolean is
7576 if Error_Posted
(N
) then
7580 -- Get entity to be tested
7582 if Is_Entity_Name
(N
)
7583 and then Present
(Entity
(N
))
7587 -- An odd case, a procedure name gets converted to a very peculiar
7588 -- function call, and here is where we detect this happening.
7590 elsif Nkind
(N
) = N_Function_Call
7591 and then Is_Entity_Name
(Name
(N
))
7592 and then Present
(Entity
(Name
(N
)))
7596 -- Another odd case, there are at least some cases of selected
7597 -- components where the selected component is not marked as having
7598 -- an entity, even though the selector does have an entity
7600 elsif Nkind
(N
) = N_Selected_Component
7601 and then Present
(Entity
(Selector_Name
(N
)))
7603 Enode
:= Selector_Name
(N
);
7609 -- Now test the entity we got to see if it is a bad case
7611 case Ekind
(Entity
(Enode
)) is
7614 ("package name cannot be used as operand", Enode
);
7616 when Generic_Unit_Kind
=>
7618 ("generic unit name cannot be used as operand", Enode
);
7622 ("subtype name cannot be used as operand", Enode
);
7626 ("entry name cannot be used as operand", Enode
);
7630 ("procedure name cannot be used as operand", Enode
);
7634 ("exception name cannot be used as operand", Enode
);
7641 ("label name cannot be used as operand", Enode
);
7650 --------------------
7651 -- Operator_Check --
7652 --------------------
7654 procedure Operator_Check
(N
: Node_Id
) is
7656 Remove_Abstract_Operations
(N
);
7658 -- Test for case of no interpretation found for operator
7660 if Etype
(N
) = Any_Type
then
7662 L
: constant Node_Id
:=
7663 (if Nkind
(N
) in N_Binary_Op
then Left_Opnd
(N
) else Empty
);
7664 R
: constant Node_Id
:= Right_Opnd
(N
);
7667 -- If either operand has no type, then don't complain further,
7668 -- since this simply means that we have a propagated error.
7671 or else Etype
(R
) = Any_Type
7672 or else (Nkind
(N
) in N_Binary_Op
and then Etype
(L
) = Any_Type
)
7674 -- For the rather unusual case where one of the operands is
7675 -- a Raise_Expression, whose initial type is Any_Type, use
7676 -- the type of the other operand.
7678 if Nkind
(L
) = N_Raise_Expression
then
7679 Set_Etype
(L
, Etype
(R
));
7680 Set_Etype
(N
, Etype
(R
));
7682 elsif Nkind
(R
) = N_Raise_Expression
then
7683 Set_Etype
(R
, Etype
(L
));
7684 Set_Etype
(N
, Etype
(L
));
7689 -- We explicitly check for the case of concatenation of component
7690 -- with component to avoid reporting spurious matching array types
7691 -- that might happen to be lurking in distant packages (such as
7692 -- run-time packages). This also prevents inconsistencies in the
7693 -- messages for certain ACVC B tests, which can vary depending on
7694 -- types declared in run-time interfaces. Another improvement when
7695 -- aggregates are present is to look for a well-typed operand.
7697 elsif Present
(Candidate_Type
)
7698 and then (Nkind
(N
) /= N_Op_Concat
7699 or else Is_Array_Type
(Etype
(L
))
7700 or else Is_Array_Type
(Etype
(R
)))
7702 if Nkind
(N
) = N_Op_Concat
then
7703 if Etype
(L
) /= Any_Composite
7704 and then Is_Array_Type
(Etype
(L
))
7706 Candidate_Type
:= Etype
(L
);
7708 elsif Etype
(R
) /= Any_Composite
7709 and then Is_Array_Type
(Etype
(R
))
7711 Candidate_Type
:= Etype
(R
);
7715 Error_Msg_NE
-- CODEFIX
7716 ("operator for} is not directly visible!",
7717 N
, First_Subtype
(Candidate_Type
));
7720 U
: constant Node_Id
:=
7721 Cunit
(Get_Source_Unit
(Candidate_Type
));
7723 if Unit_Is_Visible
(U
) then
7724 Error_Msg_N
-- CODEFIX
7725 ("use clause would make operation legal!", N
);
7727 Error_Msg_NE
-- CODEFIX
7728 ("add with_clause and use_clause for&!",
7729 N
, Defining_Entity
(Unit
(U
)));
7734 -- If either operand is a junk operand (e.g. package name), then
7735 -- post appropriate error messages, but do not complain further.
7737 -- Note that the use of OR in this test instead of OR ELSE is
7738 -- quite deliberate, we may as well check both operands in the
7739 -- binary operator case.
7741 elsif Junk_Operand
(R
)
7742 or -- really mean OR here and not OR ELSE, see above
7743 (Nkind
(N
) in N_Binary_Op
and then Junk_Operand
(L
))
7747 -- The handling of user-defined literals is deferred to the second
7748 -- pass of resolution.
7750 elsif Has_Possible_User_Defined_Literal
(N
) then
7753 -- If we have a logical operator, one of whose operands is
7754 -- Boolean, then we know that the other operand cannot resolve to
7755 -- Boolean (since we got no interpretations), but in that case we
7756 -- pretty much know that the other operand should be Boolean, so
7757 -- resolve it that way (generating an error).
7759 elsif Nkind
(N
) in N_Op_And | N_Op_Or | N_Op_Xor
then
7760 if Etype
(L
) = Standard_Boolean
then
7761 Resolve
(R
, Standard_Boolean
);
7763 elsif Etype
(R
) = Standard_Boolean
then
7764 Resolve
(L
, Standard_Boolean
);
7768 -- For an arithmetic operator or comparison operator, if one
7769 -- of the operands is numeric, then we know the other operand
7770 -- is not the same numeric type. If it is a non-numeric type,
7771 -- then probably it is intended to match the other operand.
7773 elsif Nkind
(N
) in N_Op_Add
7784 -- If Allow_Integer_Address is active, check whether the
7785 -- operation becomes legal after converting an operand.
7787 if Is_Numeric_Type
(Etype
(L
))
7788 and then not Is_Numeric_Type
(Etype
(R
))
7790 if Address_Integer_Convert_OK
(Etype
(R
), Etype
(L
)) then
7792 Unchecked_Convert_To
(
7793 Standard_Address
, Relocate_Node
(L
)));
7795 Unchecked_Convert_To
(
7796 Standard_Address
, Relocate_Node
(R
)));
7798 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7799 Analyze_Comparison_Equality_Op
(N
);
7801 Analyze_Arithmetic_Op
(N
);
7804 Resolve
(R
, Etype
(L
));
7809 elsif Is_Numeric_Type
(Etype
(R
))
7810 and then not Is_Numeric_Type
(Etype
(L
))
7812 if Address_Integer_Convert_OK
(Etype
(L
), Etype
(R
)) then
7814 Unchecked_Convert_To
(
7815 Standard_Address
, Relocate_Node
(L
)));
7817 Unchecked_Convert_To
(
7818 Standard_Address
, Relocate_Node
(R
)));
7820 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7821 Analyze_Comparison_Equality_Op
(N
);
7823 Analyze_Arithmetic_Op
(N
);
7829 Resolve
(L
, Etype
(R
));
7834 elsif Allow_Integer_Address
7835 and then Is_Descendant_Of_Address
(Etype
(L
))
7836 and then Is_Descendant_Of_Address
(Etype
(R
))
7837 and then not Error_Posted
(N
)
7840 Addr_Type
: constant Entity_Id
:= Etype
(L
);
7844 Unchecked_Convert_To
(
7845 Standard_Address
, Relocate_Node
(L
)));
7847 Unchecked_Convert_To
(
7848 Standard_Address
, Relocate_Node
(R
)));
7850 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7851 Analyze_Comparison_Equality_Op
(N
);
7853 Analyze_Arithmetic_Op
(N
);
7856 -- If this is an operand in an enclosing arithmetic
7857 -- operation, Convert the result as an address so that
7858 -- arithmetic folding of address can continue.
7860 if Nkind
(Parent
(N
)) in N_Op
then
7862 Unchecked_Convert_To
(Addr_Type
, Relocate_Node
(N
)));
7868 -- Under relaxed RM semantics silently replace occurrences of
7869 -- null by System.Address_Null.
7871 elsif Null_To_Null_Address_Convert_OK
(N
) then
7872 Replace_Null_By_Null_Address
(N
);
7874 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7875 Analyze_Comparison_Equality_Op
(N
);
7877 Analyze_Arithmetic_Op
(N
);
7883 -- Comparisons on A'Access are common enough to deserve a
7886 elsif Nkind
(N
) in N_Op_Eq | N_Op_Ne
7887 and then Ekind
(Etype
(L
)) = E_Access_Attribute_Type
7888 and then Ekind
(Etype
(R
)) = E_Access_Attribute_Type
7891 ("two access attributes cannot be compared directly", N
);
7893 ("\use qualified expression for one of the operands",
7897 -- Another one for C programmers
7899 elsif Nkind
(N
) = N_Op_Concat
7900 and then Valid_Boolean_Arg
(Etype
(L
))
7901 and then Valid_Boolean_Arg
(Etype
(R
))
7903 Error_Msg_N
("invalid operands for concatenation", N
);
7904 Error_Msg_N
-- CODEFIX
7905 ("\maybe AND was meant", N
);
7908 -- A special case for comparison of access parameter with null
7910 elsif Nkind
(N
) = N_Op_Eq
7911 and then Is_Entity_Name
(L
)
7912 and then Nkind
(Parent
(Entity
(L
))) = N_Parameter_Specification
7913 and then Nkind
(Parameter_Type
(Parent
(Entity
(L
)))) =
7915 and then Nkind
(R
) = N_Null
7917 Error_Msg_N
("access parameter is not allowed to be null", L
);
7918 Error_Msg_N
("\(call would raise Constraint_Error)", L
);
7921 -- Another special case for exponentiation, where the right
7922 -- operand must be Natural, independently of the base.
7924 elsif Nkind
(N
) = N_Op_Expon
7925 and then Is_Numeric_Type
(Etype
(L
))
7926 and then not Is_Overloaded
(R
)
7928 First_Subtype
(Base_Type
(Etype
(R
))) /= Standard_Integer
7929 and then Base_Type
(Etype
(R
)) /= Universal_Integer
7931 if Ada_Version
>= Ada_2012
7932 and then Has_Dimension_System
(Etype
(L
))
7935 ("exponent for dimensioned type must be a rational" &
7936 ", found}", R
, Etype
(R
));
7939 ("exponent must be of type Natural, found}", R
, Etype
(R
));
7944 elsif Nkind
(N
) in N_Op_Eq | N_Op_Ne
then
7945 if Address_Integer_Convert_OK
(Etype
(R
), Etype
(L
)) then
7947 Unchecked_Convert_To
(
7948 Standard_Address
, Relocate_Node
(L
)));
7950 Unchecked_Convert_To
(
7951 Standard_Address
, Relocate_Node
(R
)));
7952 Analyze_Comparison_Equality_Op
(N
);
7955 -- Under relaxed RM semantics silently replace occurrences of
7956 -- null by System.Address_Null.
7958 elsif Null_To_Null_Address_Convert_OK
(N
) then
7959 Replace_Null_By_Null_Address
(N
);
7960 Analyze_Comparison_Equality_Op
(N
);
7965 -- If we fall through then just give general message
7967 Unresolved_Operator
(N
);
7972 ---------------------------------------
7973 -- Has_Possible_User_Defined_Literal --
7974 ---------------------------------------
7976 function Has_Possible_User_Defined_Literal
(N
: Node_Id
) return Boolean is
7977 R
: constant Node_Id
:= Right_Opnd
(N
);
7979 procedure Check_Literal_Opnd
(Opnd
: Node_Id
);
7980 -- If an operand is a literal to which an aspect may apply,
7981 -- add the corresponding type to operator node.
7983 ------------------------
7984 -- Check_Literal_Opnd --
7985 ------------------------
7987 procedure Check_Literal_Opnd
(Opnd
: Node_Id
) is
7989 if Nkind
(Opnd
) in N_Numeric_Or_String_Literal
7990 or else (Is_Entity_Name
(Opnd
)
7991 and then Present
(Entity
(Opnd
))
7992 and then Is_Named_Number
(Entity
(Opnd
)))
7994 Add_One_Interp
(N
, Etype
(Opnd
), Etype
(Opnd
));
7996 end Check_Literal_Opnd
;
7998 -- Start of processing for Has_Possible_User_Defined_Literal
8001 if Ada_Version
< Ada_2022
then
8005 Check_Literal_Opnd
(R
);
8007 -- Check left operand only if right one did not provide a
8008 -- possible interpretation. Note that literal types are not
8009 -- overloadable, in the sense that there is no overloadable
8010 -- entity name whose several interpretations can be used to
8011 -- indicate possible resulting types, so there is no way to
8012 -- provide more than one interpretation to the operator node.
8013 -- The choice of one operand over the other is arbitrary at
8014 -- this point, and may lead to spurious resolution when both
8015 -- operands are literals of different kinds, but the second
8016 -- pass of resolution will examine anew both operands to
8017 -- determine whether a user-defined literal may apply to
8020 if Nkind
(N
) in N_Binary_Op
and then Etype
(N
) = Any_Type
then
8021 Check_Literal_Opnd
(Left_Opnd
(N
));
8024 return Etype
(N
) /= Any_Type
;
8025 end Has_Possible_User_Defined_Literal
;
8027 -----------------------------------------------
8028 -- Nondispatching_Call_To_Abstract_Operation --
8029 -----------------------------------------------
8031 procedure Nondispatching_Call_To_Abstract_Operation
8033 Abstract_Op
: Entity_Id
)
8035 Typ
: constant Entity_Id
:= Etype
(N
);
8038 -- In an instance body, this is a runtime check, but one we know will
8039 -- fail, so give an appropriate warning. As usual this kind of warning
8040 -- is an error in SPARK mode.
8042 Error_Msg_Sloc
:= Sloc
(Abstract_Op
);
8044 if In_Instance_Body
and then SPARK_Mode
/= On
then
8046 ("??cannot call abstract operation& declared#",
8048 Error_Msg_N
("\Program_Error [??", N
);
8050 Make_Raise_Program_Error
(Sloc
(N
),
8051 Reason
=> PE_Explicit_Raise
));
8057 ("cannot call abstract operation& declared#",
8059 Set_Etype
(N
, Any_Type
);
8061 end Nondispatching_Call_To_Abstract_Operation
;
8063 ----------------------------------------------
8064 -- Possible_Type_For_Conditional_Expression --
8065 ----------------------------------------------
8067 function Possible_Type_For_Conditional_Expression
8068 (T1
, T2
: Entity_Id
) return Entity_Id
8070 function Is_Access_Protected_Subprogram_Attribute
8071 (T
: Entity_Id
) return Boolean;
8072 -- Return true if T is the type of an access-to-protected-subprogram
8075 function Is_Access_Subprogram_Attribute
(T
: Entity_Id
) return Boolean;
8076 -- Return true if T is the type of an access-to-subprogram attribute
8078 ----------------------------------------------
8079 -- Is_Access_Protected_Subprogram_Attribute --
8080 ----------------------------------------------
8082 function Is_Access_Protected_Subprogram_Attribute
8083 (T
: Entity_Id
) return Boolean
8086 return Ekind
(T
) = E_Access_Protected_Subprogram_Type
8087 and then Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
;
8088 end Is_Access_Protected_Subprogram_Attribute
;
8090 ------------------------------------
8091 -- Is_Access_Subprogram_Attribute --
8092 ------------------------------------
8094 function Is_Access_Subprogram_Attribute
(T
: Entity_Id
) return Boolean is
8096 return Ekind
(T
) = E_Access_Subprogram_Type
8097 and then Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
;
8098 end Is_Access_Subprogram_Attribute
;
8100 -- Start of processing for Possible_Type_For_Conditional_Expression
8103 -- If both types are those of similar access attributes or allocators,
8104 -- pick one of them, for example the first.
8106 if Ekind
(T1
) in E_Access_Attribute_Type | E_Allocator_Type
8107 and then Ekind
(T2
) in E_Access_Attribute_Type | E_Allocator_Type
8111 elsif Is_Access_Subprogram_Attribute
(T1
)
8112 and then Is_Access_Subprogram_Attribute
(T2
)
8114 Subtype_Conformant
(Designated_Type
(T1
), Designated_Type
(T2
))
8118 elsif Is_Access_Protected_Subprogram_Attribute
(T1
)
8119 and then Is_Access_Protected_Subprogram_Attribute
(T2
)
8121 Subtype_Conformant
(Designated_Type
(T1
), Designated_Type
(T2
))
8125 -- The other case to be considered is a pair of tagged types
8127 elsif Is_Tagged_Type
(T1
) and then Is_Tagged_Type
(T2
) then
8128 -- Covers performs the same checks when T1 or T2 are a CW type, so
8129 -- we don't need to do them again here.
8131 if not Is_Class_Wide_Type
(T1
) and then Is_Ancestor
(T1
, T2
) then
8134 elsif not Is_Class_Wide_Type
(T2
) and then Is_Ancestor
(T2
, T1
) then
8137 -- Neither type is an ancestor of the other, but they may have one in
8138 -- common, so we pick the first type as above. We could perform here
8139 -- the computation of the nearest common ancestors of T1 and T2, but
8140 -- this would require a significant amount of work and the practical
8141 -- benefit would very likely be negligible.
8147 -- Otherwise no type is possible
8152 end Possible_Type_For_Conditional_Expression
;
8154 --------------------------------
8155 -- Remove_Abstract_Operations --
8156 --------------------------------
8158 procedure Remove_Abstract_Operations
(N
: Node_Id
) is
8159 Abstract_Op
: Entity_Id
:= Empty
;
8160 Address_Descendant
: Boolean := False;
8164 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
8165 -- activate this if either extensions are enabled, or if the abstract
8166 -- operation in question comes from a predefined file. This latter test
8167 -- allows us to use abstract to make operations invisible to users. In
8168 -- particular, if type Address is non-private and abstract subprograms
8169 -- are used to hide its operators, they will be truly hidden.
8171 type Operand_Position
is (First_Op
, Second_Op
);
8172 Univ_Type
: constant Entity_Id
:= Universal_Interpretation
(N
);
8174 procedure Remove_Address_Interpretations
(Op
: Operand_Position
);
8175 -- Ambiguities may arise when the operands are literal and the address
8176 -- operations in s-auxdec are visible. In that case, remove the
8177 -- interpretation of a literal as Address, to retain the semantics
8178 -- of Address as a private type.
8180 ------------------------------------
8181 -- Remove_Address_Interpretations --
8182 ------------------------------------
8184 procedure Remove_Address_Interpretations
(Op
: Operand_Position
) is
8188 if Is_Overloaded
(N
) then
8189 Get_First_Interp
(N
, I
, It
);
8190 while Present
(It
.Nam
) loop
8191 Formal
:= First_Entity
(It
.Nam
);
8193 if Op
= Second_Op
then
8194 Next_Entity
(Formal
);
8197 if Is_Descendant_Of_Address
(Etype
(Formal
)) then
8198 Address_Descendant
:= True;
8202 Get_Next_Interp
(I
, It
);
8205 end Remove_Address_Interpretations
;
8207 -- Start of processing for Remove_Abstract_Operations
8210 if Is_Overloaded
(N
) then
8211 if Debug_Flag_V
then
8212 Write_Line
("Remove_Abstract_Operations: ");
8213 Write_Overloads
(N
);
8216 Get_First_Interp
(N
, I
, It
);
8218 while Present
(It
.Nam
) loop
8219 if Is_Overloadable
(It
.Nam
)
8220 and then Is_Abstract_Subprogram
(It
.Nam
)
8221 and then not Is_Dispatching_Operation
(It
.Nam
)
8223 Abstract_Op
:= It
.Nam
;
8225 if Is_Descendant_Of_Address
(It
.Typ
) then
8226 Address_Descendant
:= True;
8230 -- In Ada 2005, this operation does not participate in overload
8231 -- resolution. If the operation is defined in a predefined
8232 -- unit, it is one of the operations declared abstract in some
8233 -- variants of System, and it must be removed as well.
8235 elsif Ada_Version
>= Ada_2005
8236 or else In_Predefined_Unit
(It
.Nam
)
8243 Get_Next_Interp
(I
, It
);
8246 if No
(Abstract_Op
) then
8248 -- If some interpretation yields an integer type, it is still
8249 -- possible that there are address interpretations. Remove them
8250 -- if one operand is a literal, to avoid spurious ambiguities
8251 -- on systems where Address is a visible integer type.
8253 if Is_Overloaded
(N
)
8254 and then Nkind
(N
) in N_Op
8255 and then Is_Integer_Type
(Etype
(N
))
8257 if Nkind
(N
) in N_Binary_Op
then
8258 if Nkind
(Right_Opnd
(N
)) = N_Integer_Literal
then
8259 Remove_Address_Interpretations
(Second_Op
);
8261 elsif Nkind
(Left_Opnd
(N
)) = N_Integer_Literal
then
8262 Remove_Address_Interpretations
(First_Op
);
8267 elsif Nkind
(N
) in N_Op
then
8269 -- Remove interpretations that treat literals as addresses. This
8270 -- is never appropriate, even when Address is defined as a visible
8271 -- Integer type. The reason is that we would really prefer Address
8272 -- to behave as a private type, even in this case. If Address is a
8273 -- visible integer type, we get lots of overload ambiguities.
8275 if Nkind
(N
) in N_Binary_Op
then
8277 U1
: constant Boolean :=
8278 Present
(Universal_Interpretation
(Right_Opnd
(N
)));
8279 U2
: constant Boolean :=
8280 Present
(Universal_Interpretation
(Left_Opnd
(N
)));
8284 Remove_Address_Interpretations
(Second_Op
);
8288 Remove_Address_Interpretations
(First_Op
);
8291 if not (U1
and U2
) then
8293 -- Remove corresponding predefined operator, which is
8294 -- always added to the overload set.
8296 Get_First_Interp
(N
, I
, It
);
8297 while Present
(It
.Nam
) loop
8298 if Scope
(It
.Nam
) = Standard_Standard
8299 and then Base_Type
(It
.Typ
) =
8300 Base_Type
(Etype
(Abstract_Op
))
8305 Get_Next_Interp
(I
, It
);
8308 elsif Is_Overloaded
(N
)
8309 and then Present
(Univ_Type
)
8311 -- If both operands have a universal interpretation,
8312 -- it is still necessary to remove interpretations that
8313 -- yield Address. Any remaining ambiguities will be
8314 -- removed in Disambiguate.
8316 Get_First_Interp
(N
, I
, It
);
8317 while Present
(It
.Nam
) loop
8318 if Is_Descendant_Of_Address
(It
.Typ
) then
8321 elsif not Is_Type
(It
.Nam
) then
8322 Set_Entity
(N
, It
.Nam
);
8325 Get_Next_Interp
(I
, It
);
8331 elsif Nkind
(N
) = N_Function_Call
8333 (Nkind
(Name
(N
)) = N_Operator_Symbol
8335 (Nkind
(Name
(N
)) = N_Expanded_Name
8337 Nkind
(Selector_Name
(Name
(N
))) = N_Operator_Symbol
))
8341 Arg1
: constant Node_Id
:= First
(Parameter_Associations
(N
));
8342 U1
: constant Boolean :=
8343 Present
(Universal_Interpretation
(Arg1
));
8344 U2
: constant Boolean :=
8345 Present
(Next
(Arg1
)) and then
8346 Present
(Universal_Interpretation
(Next
(Arg1
)));
8350 Remove_Address_Interpretations
(First_Op
);
8354 Remove_Address_Interpretations
(Second_Op
);
8357 if not (U1
and U2
) then
8358 Get_First_Interp
(N
, I
, It
);
8359 while Present
(It
.Nam
) loop
8360 if Scope
(It
.Nam
) = Standard_Standard
8361 and then It
.Typ
= Base_Type
(Etype
(Abstract_Op
))
8366 Get_Next_Interp
(I
, It
);
8372 -- If the removal has left no valid interpretations, emit an error
8373 -- message now and label node as illegal.
8375 if Present
(Abstract_Op
) then
8376 Get_First_Interp
(N
, I
, It
);
8380 -- Removal of abstract operation left no viable candidate
8382 Nondispatching_Call_To_Abstract_Operation
(N
, Abstract_Op
);
8384 -- In Ada 2005, an abstract operation may disable predefined
8385 -- operators. Since the context is not yet known, we mark the
8386 -- predefined operators as potentially hidden. Do not include
8387 -- predefined operators when addresses are involved since this
8388 -- case is handled separately.
8390 elsif Ada_Version
>= Ada_2005
and then not Address_Descendant
then
8391 while Present
(It
.Nam
) loop
8392 if Is_Numeric_Type
(It
.Typ
)
8393 and then Scope
(It
.Typ
) = Standard_Standard
8394 and then Ekind
(It
.Nam
) = E_Operator
8396 Set_Abstract_Op
(I
, Abstract_Op
);
8399 Get_Next_Interp
(I
, It
);
8404 if Debug_Flag_V
then
8405 Write_Line
("Remove_Abstract_Operations done: ");
8406 Write_Overloads
(N
);
8409 end Remove_Abstract_Operations
;
8411 ----------------------------
8412 -- Try_Container_Indexing --
8413 ----------------------------
8415 function Try_Container_Indexing
8418 Exprs
: List_Id
) return Boolean
8420 Pref_Typ
: Entity_Id
:= Etype
(Prefix
);
8422 function Constant_Indexing_OK
return Boolean;
8423 -- Constant_Indexing is legal if there is no Variable_Indexing defined
8424 -- for the type, or else node not a target of assignment, or an actual
8425 -- for an IN OUT or OUT formal (RM 4.1.6 (11)).
8427 function Expr_Matches_In_Formal
8429 Par
: Node_Id
) return Boolean;
8430 -- Find formal corresponding to given indexed component that is an
8431 -- actual in a call. Note that the enclosing subprogram call has not
8432 -- been analyzed yet, and the parameter list is not normalized, so
8433 -- that if the argument is a parameter association we must match it
8434 -- by name and not by position.
8436 function Find_Indexing_Operations
8439 Is_Constant
: Boolean) return Node_Id
;
8440 -- Return a reference to the primitive operation of type T denoted by
8441 -- name Nam. If the operation is overloaded, the reference carries all
8442 -- interpretations. Flag Is_Constant should be set when the context is
8443 -- constant indexing.
8445 --------------------------
8446 -- Constant_Indexing_OK --
8447 --------------------------
8449 function Constant_Indexing_OK
return Boolean is
8453 if No
(Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Variable_Indexing
)) then
8456 elsif not Is_Variable
(Prefix
) then
8461 while Present
(Par
) loop
8462 if Nkind
(Parent
(Par
)) = N_Assignment_Statement
8463 and then Par
= Name
(Parent
(Par
))
8467 -- The call may be overloaded, in which case we assume that its
8468 -- resolution does not depend on the type of the parameter that
8469 -- includes the indexing operation.
8471 elsif Nkind
(Parent
(Par
)) in N_Subprogram_Call
then
8473 if not Is_Entity_Name
(Name
(Parent
(Par
))) then
8475 -- ??? We don't know what to do with an N_Selected_Component
8476 -- node for a prefixed-notation call to AA.BB where AA's
8477 -- type is known, but BB has not yet been resolved. In that
8478 -- case, the preceding Is_Entity_Name call returns False.
8479 -- Incorrectly returning False here will usually work
8480 -- better than incorrectly returning True, so that's what
8490 -- We should look for an interpretation with the proper
8491 -- number of formals, and determine whether it is an
8492 -- In_Parameter, but for now we examine the formal that
8493 -- corresponds to the indexing, and assume that variable
8494 -- indexing is required if some interpretation has an
8495 -- assignable formal at that position. Still does not
8496 -- cover the most complex cases ???
8498 if Is_Overloaded
(Name
(Parent
(Par
))) then
8500 Proc
: constant Node_Id
:= Name
(Parent
(Par
));
8505 Get_First_Interp
(Proc
, I
, It
);
8506 while Present
(It
.Nam
) loop
8507 if not Expr_Matches_In_Formal
(It
.Nam
, Par
) then
8511 Get_Next_Interp
(I
, It
);
8515 -- All interpretations have a matching in-mode formal
8520 Proc
:= Entity
(Name
(Parent
(Par
)));
8522 -- If this is an indirect call, get formals from
8525 if Is_Access_Subprogram_Type
(Etype
(Proc
)) then
8526 Proc
:= Designated_Type
(Etype
(Proc
));
8530 return Expr_Matches_In_Formal
(Proc
, Par
);
8533 elsif Nkind
(Parent
(Par
)) = N_Object_Renaming_Declaration
then
8536 -- If the indexed component is a prefix it may be the first actual
8537 -- of a prefixed call. Retrieve the called entity, if any, and
8538 -- check its first formal. Determine if the context is a procedure
8539 -- or function call.
8541 elsif Nkind
(Parent
(Par
)) = N_Selected_Component
then
8543 Sel
: constant Node_Id
:= Selector_Name
(Parent
(Par
));
8544 Nam
: constant Entity_Id
:= Current_Entity
(Sel
);
8547 if Present
(Nam
) and then Is_Overloadable
(Nam
) then
8548 if Nkind
(Parent
(Parent
(Par
))) =
8549 N_Procedure_Call_Statement
8553 elsif Ekind
(Nam
) = E_Function
8554 and then Present
(First_Formal
(Nam
))
8556 return Ekind
(First_Formal
(Nam
)) = E_In_Parameter
;
8561 elsif Nkind
(Par
) in N_Op
then
8565 Par
:= Parent
(Par
);
8568 -- In all other cases, constant indexing is legal
8571 end Constant_Indexing_OK
;
8573 ----------------------------
8574 -- Expr_Matches_In_Formal --
8575 ----------------------------
8577 function Expr_Matches_In_Formal
8579 Par
: Node_Id
) return Boolean
8585 Formal
:= First_Formal
(Subp
);
8586 Actual
:= First
(Parameter_Associations
((Parent
(Par
))));
8588 if Nkind
(Par
) /= N_Parameter_Association
then
8590 -- Match by position
8592 while Present
(Actual
) and then Present
(Formal
) loop
8593 exit when Actual
= Par
;
8596 if Present
(Formal
) then
8597 Next_Formal
(Formal
);
8599 -- Otherwise this is a parameter mismatch, the error is
8600 -- reported elsewhere, or else variable indexing is implied.
8610 while Present
(Formal
) loop
8611 exit when Chars
(Formal
) = Chars
(Selector_Name
(Par
));
8612 Next_Formal
(Formal
);
8620 return Present
(Formal
) and then Ekind
(Formal
) = E_In_Parameter
;
8621 end Expr_Matches_In_Formal
;
8623 ------------------------------
8624 -- Find_Indexing_Operations --
8625 ------------------------------
8627 function Find_Indexing_Operations
8630 Is_Constant
: Boolean) return Node_Id
8632 procedure Inspect_Declarations
8634 Ref
: in out Node_Id
);
8635 -- Traverse the declarative list where type Typ resides and collect
8636 -- all suitable interpretations in node Ref.
8638 procedure Inspect_Primitives
8640 Ref
: in out Node_Id
);
8641 -- Traverse the list of primitive operations of type Typ and collect
8642 -- all suitable interpretations in node Ref.
8644 function Is_OK_Candidate
8645 (Subp_Id
: Entity_Id
;
8646 Typ
: Entity_Id
) return Boolean;
8647 -- Determine whether subprogram Subp_Id is a suitable indexing
8648 -- operation for type Typ. To qualify as such, the subprogram must
8649 -- be a function, have at least two parameters, and the type of the
8650 -- first parameter must be either Typ, or Typ'Class, or access [to
8651 -- constant] with designated type Typ or Typ'Class.
8653 procedure Record_Interp
(Subp_Id
: Entity_Id
; Ref
: in out Node_Id
);
8654 -- Store subprogram Subp_Id as an interpretation in node Ref
8656 --------------------------
8657 -- Inspect_Declarations --
8658 --------------------------
8660 procedure Inspect_Declarations
8662 Ref
: in out Node_Id
)
8664 Typ_Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
8666 Subp_Id
: Entity_Id
;
8669 -- Ensure that the routine is not called with itypes, which lack a
8670 -- declarative node.
8672 pragma Assert
(Present
(Typ_Decl
));
8673 pragma Assert
(Is_List_Member
(Typ_Decl
));
8675 Decl
:= First
(List_Containing
(Typ_Decl
));
8676 while Present
(Decl
) loop
8677 if Nkind
(Decl
) = N_Subprogram_Declaration
then
8678 Subp_Id
:= Defining_Entity
(Decl
);
8680 if Is_OK_Candidate
(Subp_Id
, Typ
) then
8681 Record_Interp
(Subp_Id
, Ref
);
8687 end Inspect_Declarations
;
8689 ------------------------
8690 -- Inspect_Primitives --
8691 ------------------------
8693 procedure Inspect_Primitives
8695 Ref
: in out Node_Id
)
8697 Prim_Elmt
: Elmt_Id
;
8698 Prim_Id
: Entity_Id
;
8701 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
8702 while Present
(Prim_Elmt
) loop
8703 Prim_Id
:= Node
(Prim_Elmt
);
8705 if Is_OK_Candidate
(Prim_Id
, Typ
) then
8706 Record_Interp
(Prim_Id
, Ref
);
8709 Next_Elmt
(Prim_Elmt
);
8711 end Inspect_Primitives
;
8713 ---------------------
8714 -- Is_OK_Candidate --
8715 ---------------------
8717 function Is_OK_Candidate
8718 (Subp_Id
: Entity_Id
;
8719 Typ
: Entity_Id
) return Boolean
8722 Formal_Typ
: Entity_Id
;
8723 Param_Typ
: Node_Id
;
8726 -- To classify as a suitable candidate, the subprogram must be a
8727 -- function whose name matches the argument of aspect Constant or
8728 -- Variable_Indexing.
8730 if Ekind
(Subp_Id
) = E_Function
and then Chars
(Subp_Id
) = Nam
then
8731 Formal
:= First_Formal
(Subp_Id
);
8733 -- The candidate requires at least two parameters
8735 if Present
(Formal
) and then Present
(Next_Formal
(Formal
)) then
8736 Formal_Typ
:= Empty
;
8737 Param_Typ
:= Parameter_Type
(Parent
(Formal
));
8739 -- Use the designated type when the first parameter is of an
8742 if Nkind
(Param_Typ
) = N_Access_Definition
8743 and then Present
(Subtype_Mark
(Param_Typ
))
8745 -- When the context is a constant indexing, the access
8746 -- definition must be access-to-constant. This does not
8747 -- apply to variable indexing.
8750 or else Constant_Present
(Param_Typ
)
8752 Formal_Typ
:= Etype
(Subtype_Mark
(Param_Typ
));
8755 -- Otherwise use the parameter type
8758 Formal_Typ
:= Etype
(Param_Typ
);
8761 if Present
(Formal_Typ
) then
8763 -- Use the specific type when the parameter type is
8766 if Is_Class_Wide_Type
(Formal_Typ
) then
8767 Formal_Typ
:= Etype
(Base_Type
(Formal_Typ
));
8770 -- Use the full view when the parameter type is private
8773 if Is_Incomplete_Or_Private_Type
(Formal_Typ
)
8774 and then Present
(Full_View
(Formal_Typ
))
8776 Formal_Typ
:= Full_View
(Formal_Typ
);
8779 -- The type of the first parameter must denote the type
8780 -- of the container or acts as its ancestor type.
8784 or else Is_Ancestor
(Formal_Typ
, Typ
);
8790 end Is_OK_Candidate
;
8796 procedure Record_Interp
(Subp_Id
: Entity_Id
; Ref
: in out Node_Id
) is
8798 if Present
(Ref
) then
8799 Add_One_Interp
(Ref
, Subp_Id
, Etype
(Subp_Id
));
8801 -- Otherwise this is the first interpretation. Create a reference
8802 -- where all remaining interpretations will be collected.
8805 Ref
:= New_Occurrence_Of
(Subp_Id
, Sloc
(T
));
8814 -- Start of processing for Find_Indexing_Operations
8819 -- Use the specific type when the parameter type is class-wide
8821 if Is_Class_Wide_Type
(Typ
) then
8822 Typ
:= Root_Type
(Typ
);
8826 Typ
:= Underlying_Type
(Base_Type
(Typ
));
8828 Inspect_Primitives
(Typ
, Ref
);
8830 -- Now look for explicit declarations of an indexing operation.
8831 -- If the type is private the operation may be declared in the
8832 -- visible part that contains the partial view.
8834 if Is_Private_Type
(T
) then
8835 Inspect_Declarations
(T
, Ref
);
8838 Inspect_Declarations
(Typ
, Ref
);
8841 end Find_Indexing_Operations
;
8845 Loc
: constant Source_Ptr
:= Sloc
(N
);
8849 Func_Name
: Node_Id
;
8852 Is_Constant_Indexing
: Boolean := False;
8853 -- This flag reflects the nature of the container indexing. Note that
8854 -- the context may be suited for constant indexing, but the type may
8855 -- lack a Constant_Indexing annotation.
8857 -- Start of processing for Try_Container_Indexing
8860 -- Node may have been analyzed already when testing for a prefixed
8861 -- call, in which case do not redo analysis.
8863 if Present
(Generalized_Indexing
(N
)) then
8867 -- An explicit dereference needs to be created in the case of a prefix
8868 -- that's an access.
8870 -- It seems that this should be done elsewhere, but not clear where that
8871 -- should happen. Normally Insert_Explicit_Dereference is called via
8872 -- Resolve_Implicit_Dereference, called from Resolve_Indexed_Component,
8873 -- but that won't be called in this case because we transform the
8874 -- indexing to a call. Resolve_Call.Check_Prefixed_Call takes care of
8875 -- implicit dereferencing and referencing on prefixed calls, but that
8876 -- would be too late, even if we expanded to a prefix call, because
8877 -- Process_Indexed_Component will flag an error before the resolution
8880 if Is_Access_Type
(Pref_Typ
) then
8881 Pref_Typ
:= Implicitly_Designated_Type
(Pref_Typ
);
8882 Insert_Explicit_Dereference
(Prefix
);
8883 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
8888 -- If indexing a class-wide container, obtain indexing primitive from
8891 if Is_Class_Wide_Type
(C_Type
) then
8892 C_Type
:= Etype
(Base_Type
(C_Type
));
8895 -- Check whether the type has a specified indexing aspect
8899 -- The context is suitable for constant indexing, so obtain the name of
8900 -- the indexing function from aspect Constant_Indexing.
8902 if Constant_Indexing_OK
then
8904 Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Constant_Indexing
);
8907 if Present
(Func_Name
) then
8908 Is_Constant_Indexing
:= True;
8910 -- Otherwise attempt variable indexing
8914 Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Variable_Indexing
);
8917 -- The type is not subject to either form of indexing, therefore the
8918 -- indexed component does not denote container indexing. If this is a
8919 -- true error, it is diagnosed by the caller.
8921 if No
(Func_Name
) then
8923 -- The prefix itself may be an indexing of a container. Rewrite it
8924 -- as such and retry.
8926 if Has_Implicit_Dereference
(Pref_Typ
) then
8927 Build_Explicit_Dereference
8928 (Prefix
, Get_Reference_Discriminant
(Pref_Typ
));
8929 return Try_Container_Indexing
(N
, Prefix
, Exprs
);
8931 -- Otherwise this is definitely not container indexing
8937 -- If the container type is derived from another container type, the
8938 -- value of the inherited aspect is the Reference operation declared
8939 -- for the parent type.
8941 -- However, Reference is also a primitive operation of the type, and the
8942 -- inherited operation has a different signature. We retrieve the right
8943 -- ones (the function may be overloaded) from the list of primitive
8944 -- operations of the derived type.
8946 -- Note that predefined containers are typically all derived from one of
8947 -- the Controlled types. The code below is motivated by containers that
8948 -- are derived from other types with a Reference aspect.
8949 -- Note as well that we need to examine the base type, given that
8950 -- the container object may be a constrained subtype or itype that
8951 -- does not have an explicit declaration.
8953 elsif Is_Derived_Type
(C_Type
)
8954 and then Etype
(First_Formal
(Entity
(Func_Name
))) /= Pref_Typ
8957 Find_Indexing_Operations
8958 (T
=> Base_Type
(C_Type
),
8959 Nam
=> Chars
(Func_Name
),
8960 Is_Constant
=> Is_Constant_Indexing
);
8963 Assoc
:= New_List
(Relocate_Node
(Prefix
));
8965 -- A generalized indexing may have nore than one index expression, so
8966 -- transfer all of them to the argument list to be used in the call.
8967 -- Note that there may be named associations, in which case the node
8968 -- was rewritten earlier as a call, and has been transformed back into
8969 -- an indexed expression to share the following processing.
8971 -- The generalized indexing node is the one on which analysis and
8972 -- resolution take place. Before expansion the original node is replaced
8973 -- with the generalized indexing node, which is a call, possibly with a
8974 -- dereference operation.
8976 -- Create argument list for function call that represents generalized
8977 -- indexing. Note that indices (i.e. actuals) may themselves be
8985 Arg
:= First
(Exprs
);
8986 while Present
(Arg
) loop
8987 New_Arg
:= Relocate_Node
(Arg
);
8989 -- The arguments can be parameter associations, in which case the
8990 -- explicit actual parameter carries the overloadings.
8992 if Nkind
(New_Arg
) /= N_Parameter_Association
then
8993 Save_Interps
(Arg
, New_Arg
);
8996 Append
(New_Arg
, Assoc
);
9001 if not Is_Overloaded
(Func_Name
) then
9002 Func
:= Entity
(Func_Name
);
9004 -- Can happen in case of e.g. cascaded errors
9011 Make_Function_Call
(Loc
,
9012 Name
=> New_Occurrence_Of
(Func
, Loc
),
9013 Parameter_Associations
=> Assoc
);
9015 Set_Parent
(Indexing
, Parent
(N
));
9016 Set_Generalized_Indexing
(N
, Indexing
);
9018 Set_Etype
(N
, Etype
(Indexing
));
9020 -- If the return type of the indexing function is a reference type,
9021 -- add the dereference as a possible interpretation. Note that the
9022 -- indexing aspect may be a function that returns the element type
9023 -- with no intervening implicit dereference, and that the reference
9024 -- discriminant is not the first discriminant.
9026 if Has_Discriminants
(Etype
(Func
)) then
9027 Check_Implicit_Dereference
(N
, Etype
(Func
));
9031 -- If there are multiple indexing functions, build a function call
9032 -- and analyze it for each of the possible interpretations.
9035 Make_Function_Call
(Loc
,
9037 Make_Identifier
(Loc
, Chars
(Func_Name
)),
9038 Parameter_Associations
=> Assoc
);
9039 Set_Parent
(Indexing
, Parent
(N
));
9040 Set_Generalized_Indexing
(N
, Indexing
);
9041 Set_Etype
(N
, Any_Type
);
9042 Set_Etype
(Name
(Indexing
), Any_Type
);
9050 Get_First_Interp
(Func_Name
, I
, It
);
9051 Set_Etype
(Indexing
, Any_Type
);
9053 -- Analyze each candidate function with the given actuals
9055 while Present
(It
.Nam
) loop
9056 Analyze_One_Call
(Indexing
, It
.Nam
, False, Success
);
9057 Get_Next_Interp
(I
, It
);
9060 -- If there are several successful candidates, resolution will
9061 -- be by result. Mark the interpretations of the function name
9064 if Is_Overloaded
(Indexing
) then
9065 Get_First_Interp
(Indexing
, I
, It
);
9067 while Present
(It
.Nam
) loop
9068 Add_One_Interp
(Name
(Indexing
), It
.Nam
, It
.Typ
);
9069 Get_Next_Interp
(I
, It
);
9073 Set_Etype
(Name
(Indexing
), Etype
(Indexing
));
9076 -- Now add the candidate interpretations to the indexing node
9077 -- itself, to be replaced later by the function call.
9079 if Is_Overloaded
(Name
(Indexing
)) then
9080 Get_First_Interp
(Name
(Indexing
), I
, It
);
9082 while Present
(It
.Nam
) loop
9083 Add_One_Interp
(N
, It
.Nam
, It
.Typ
);
9085 -- Add dereference interpretation if the result type has
9086 -- implicit reference discriminants.
9088 if Has_Discriminants
(Etype
(It
.Nam
)) then
9089 Check_Implicit_Dereference
(N
, Etype
(It
.Nam
));
9092 Get_Next_Interp
(I
, It
);
9096 Set_Etype
(N
, Etype
(Name
(Indexing
)));
9097 if Has_Discriminants
(Etype
(N
)) then
9098 Check_Implicit_Dereference
(N
, Etype
(N
));
9104 if Etype
(Indexing
) = Any_Type
then
9106 ("container cannot be indexed with&", N
, Etype
(First
(Exprs
)));
9107 Rewrite
(N
, New_Occurrence_Of
(Any_Id
, Loc
));
9111 end Try_Container_Indexing
;
9113 -----------------------
9114 -- Try_Indirect_Call --
9115 -----------------------
9117 function Try_Indirect_Call
9120 Typ
: Entity_Id
) return Boolean
9126 pragma Warnings
(Off
, Call_OK
);
9129 Normalize_Actuals
(N
, Designated_Type
(Typ
), False, Call_OK
);
9131 Actual
:= First_Actual
(N
);
9132 Formal
:= First_Formal
(Designated_Type
(Typ
));
9133 while Present
(Actual
) and then Present
(Formal
) loop
9134 if not Has_Compatible_Type
(Actual
, Etype
(Formal
)) then
9139 Next_Formal
(Formal
);
9142 if No
(Actual
) and then No
(Formal
) then
9143 Add_One_Interp
(N
, Nam
, Etype
(Designated_Type
(Typ
)));
9145 -- Nam is a candidate interpretation for the name in the call,
9146 -- if it is not an indirect call.
9148 if not Is_Type
(Nam
)
9149 and then Is_Entity_Name
(Name
(N
))
9151 Set_Entity
(Name
(N
), Nam
);
9159 end Try_Indirect_Call
;
9161 ----------------------
9162 -- Try_Indexed_Call --
9163 ----------------------
9165 function Try_Indexed_Call
9169 Skip_First
: Boolean) return Boolean
9171 Loc
: constant Source_Ptr
:= Sloc
(N
);
9172 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
9177 Actual
:= First
(Actuals
);
9179 -- If the call was originally written in prefix form, skip the first
9180 -- actual, which is obviously not defaulted.
9186 Index
:= First_Index
(Typ
);
9187 while Present
(Actual
) and then Present
(Index
) loop
9189 -- If the parameter list has a named association, the expression
9190 -- is definitely a call and not an indexed component.
9192 if Nkind
(Actual
) = N_Parameter_Association
then
9196 if Is_Entity_Name
(Actual
)
9197 and then Is_Type
(Entity
(Actual
))
9198 and then No
(Next
(Actual
))
9200 -- A single actual that is a type name indicates a slice if the
9201 -- type is discrete, and an error otherwise.
9203 if Is_Discrete_Type
(Entity
(Actual
)) then
9207 Make_Function_Call
(Loc
,
9208 Name
=> Relocate_Node
(Name
(N
))),
9210 New_Occurrence_Of
(Entity
(Actual
), Sloc
(Actual
))));
9215 Error_Msg_N
("invalid use of type in expression", Actual
);
9216 Set_Etype
(N
, Any_Type
);
9221 elsif not Has_Compatible_Type
(Actual
, Etype
(Index
)) then
9229 if No
(Actual
) and then No
(Index
) then
9230 Add_One_Interp
(N
, Nam
, Component_Type
(Typ
));
9232 -- Nam is a candidate interpretation for the name in the call,
9233 -- if it is not an indirect call.
9235 if not Is_Type
(Nam
)
9236 and then Is_Entity_Name
(Name
(N
))
9238 Set_Entity
(Name
(N
), Nam
);
9245 end Try_Indexed_Call
;
9247 --------------------------
9248 -- Try_Object_Operation --
9249 --------------------------
9251 function Try_Object_Operation
9253 CW_Test_Only
: Boolean := False;
9254 Allow_Extensions
: Boolean := False) return Boolean
9256 K
: constant Node_Kind
:= Nkind
(Parent
(N
));
9257 Is_Subprg_Call
: constant Boolean := K
in N_Subprogram_Call
;
9258 Loc
: constant Source_Ptr
:= Sloc
(N
);
9259 Obj
: constant Node_Id
:= Prefix
(N
);
9261 Subprog
: constant Node_Id
:=
9262 Make_Identifier
(Sloc
(Selector_Name
(N
)),
9263 Chars
=> Chars
(Selector_Name
(N
)));
9264 -- Identifier on which possible interpretations will be collected
9266 Report_Error
: Boolean := False;
9267 -- If no candidate interpretation matches the context, redo analysis
9268 -- with Report_Error True to provide additional information.
9271 Candidate
: Entity_Id
:= Empty
;
9272 New_Call_Node
: Node_Id
:= Empty
;
9273 Node_To_Replace
: Node_Id
;
9274 Obj_Type
: Entity_Id
:= Etype
(Obj
);
9275 Success
: Boolean := False;
9277 procedure Complete_Object_Operation
9278 (Call_Node
: Node_Id
;
9279 Node_To_Replace
: Node_Id
);
9280 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
9281 -- Call_Node, insert the object (or its dereference) as the first actual
9282 -- in the call, and complete the analysis of the call.
9284 procedure Report_Ambiguity
(Op
: Entity_Id
);
9285 -- If a prefixed procedure call is ambiguous, indicate whether the call
9286 -- includes an implicit dereference or an implicit 'Access.
9288 procedure Transform_Object_Operation
9289 (Call_Node
: out Node_Id
;
9290 Node_To_Replace
: out Node_Id
);
9291 -- Transform Obj.Operation (X, Y, ...) into Operation (Obj, X, Y ...).
9292 -- Call_Node is the resulting subprogram call, Node_To_Replace is
9293 -- either N or the parent of N, and Subprog is a reference to the
9294 -- subprogram we are trying to match. Note that the transformation
9295 -- may be partially destructive for the parent of N, so it needs to
9296 -- be undone in the case where Try_Object_Operation returns false.
9298 function Try_Class_Wide_Operation
9299 (Call_Node
: Node_Id
;
9300 Node_To_Replace
: Node_Id
) return Boolean;
9301 -- Traverse all ancestor types looking for a class-wide subprogram for
9302 -- which the current operation is a valid non-dispatching call.
9304 procedure Try_One_Prefix_Interpretation
(T
: Entity_Id
);
9305 -- If prefix is overloaded, its interpretation may include different
9306 -- tagged types, and we must examine the primitive operations and the
9307 -- class-wide operations of each in order to find candidate
9308 -- interpretations for the call as a whole.
9310 function Try_Primitive_Operation
9311 (Call_Node
: Node_Id
;
9312 Node_To_Replace
: Node_Id
) return Boolean;
9313 -- Traverse the list of primitive subprograms looking for a dispatching
9314 -- operation for which the current node is a valid call.
9316 function Valid_Candidate
9319 Subp
: Entity_Id
) return Entity_Id
;
9320 -- If the subprogram is a valid interpretation, record it, and add to
9321 -- the list of interpretations of Subprog. Otherwise return Empty.
9323 -------------------------------
9324 -- Complete_Object_Operation --
9325 -------------------------------
9327 procedure Complete_Object_Operation
9328 (Call_Node
: Node_Id
;
9329 Node_To_Replace
: Node_Id
)
9331 Control
: constant Entity_Id
:= First_Formal
(Entity
(Subprog
));
9332 Formal_Type
: constant Entity_Id
:= Etype
(Control
);
9333 First_Actual
: Node_Id
;
9336 -- Place the name of the operation, with its interpretations,
9337 -- on the rewritten call.
9339 Set_Name
(Call_Node
, Subprog
);
9341 First_Actual
:= First
(Parameter_Associations
(Call_Node
));
9343 -- For cross-reference purposes, treat the new node as being in the
9344 -- source if the original one is. Set entity and type, even though
9345 -- they may be overwritten during resolution if overloaded.
9347 Set_Comes_From_Source
(Subprog
, Comes_From_Source
(N
));
9348 Set_Comes_From_Source
(Call_Node
, Comes_From_Source
(N
));
9350 if Nkind
(N
) = N_Selected_Component
9351 and then not Inside_A_Generic
9353 Set_Entity
(Selector_Name
(N
), Entity
(Subprog
));
9354 Set_Etype
(Selector_Name
(N
), Etype
(Entity
(Subprog
)));
9357 -- If need be, rewrite first actual as an explicit dereference. If
9358 -- the call is overloaded, the rewriting can only be done once the
9359 -- primitive operation is identified.
9361 if Is_Overloaded
(Subprog
) then
9363 -- The prefix itself may be overloaded, and its interpretations
9364 -- must be propagated to the new actual in the call.
9366 if Is_Overloaded
(Obj
) then
9367 Save_Interps
(Obj
, First_Actual
);
9370 Rewrite
(First_Actual
, Obj
);
9372 elsif not Is_Access_Type
(Formal_Type
)
9373 and then Is_Access_Type
(Etype
(Obj
))
9375 Rewrite
(First_Actual
,
9376 Make_Explicit_Dereference
(Sloc
(Obj
), Obj
));
9377 Analyze
(First_Actual
);
9379 -- If we need to introduce an explicit dereference, verify that
9380 -- the resulting actual is compatible with the mode of the formal.
9382 if Ekind
(First_Formal
(Entity
(Subprog
))) /= E_In_Parameter
9383 and then Is_Access_Constant
(Etype
(Obj
))
9386 ("expect variable in call to&", Prefix
(N
), Entity
(Subprog
));
9389 -- Conversely, if the formal is an access parameter and the object is
9390 -- not an access type or a reference type (i.e. a type with the
9391 -- Implicit_Dereference aspect specified), replace the actual with a
9392 -- 'Access reference. Its analysis will check that the object is
9395 elsif Is_Access_Type
(Formal_Type
)
9396 and then not Is_Access_Type
(Etype
(Obj
))
9398 (not Has_Implicit_Dereference
(Etype
(Obj
))
9400 not Is_Access_Type
(Designated_Type
(Etype
9401 (Get_Reference_Discriminant
(Etype
(Obj
))))))
9403 -- A special case: A.all'Access is illegal if A is an access to a
9404 -- constant and the context requires an access to a variable.
9406 if not Is_Access_Constant
(Formal_Type
) then
9407 if (Nkind
(Obj
) = N_Explicit_Dereference
9408 and then Is_Access_Constant
(Etype
(Prefix
(Obj
))))
9409 or else not Is_Variable
(Obj
)
9412 ("actual for & must be a variable", Obj
, Control
);
9416 Rewrite
(First_Actual
,
9417 Make_Attribute_Reference
(Loc
,
9418 Attribute_Name
=> Name_Access
,
9419 Prefix
=> Relocate_Node
(Obj
)));
9421 -- If the object is not overloaded verify that taking access of
9422 -- it is legal. Otherwise check is made during resolution.
9424 if not Is_Overloaded
(Obj
)
9425 and then not Is_Aliased_View
(Obj
)
9428 ("object in prefixed call to & must be aliased "
9429 & "(RM 4.1.3 (13 1/2))", Prefix
(First_Actual
), Subprog
);
9432 Analyze
(First_Actual
);
9435 if Is_Overloaded
(Obj
) then
9436 Save_Interps
(Obj
, First_Actual
);
9439 Rewrite
(First_Actual
, Obj
);
9442 if In_Extended_Main_Source_Unit
(Current_Scope
) then
9443 -- The operation is obtained from the dispatch table and not by
9444 -- visibility, and may be declared in a unit that is not
9445 -- explicitly referenced in the source, but is nevertheless
9446 -- required in the context of the current unit. Indicate that
9447 -- operation and its scope are referenced, to prevent spurious and
9448 -- misleading warnings. If the operation is overloaded, all
9449 -- primitives are in the same scope and we can use any of them.
9450 -- Don't do that outside the main unit since otherwise this will
9451 -- e.g. prevent the detection of some unused with clauses.
9453 Set_Referenced
(Entity
(Subprog
), True);
9454 Set_Referenced
(Scope
(Entity
(Subprog
)), True);
9457 Rewrite
(Node_To_Replace
, Call_Node
);
9459 -- Propagate the interpretations collected in subprog to the new
9460 -- function call node, to be resolved from context.
9462 if Is_Overloaded
(Subprog
) then
9463 Save_Interps
(Subprog
, Node_To_Replace
);
9466 Analyze
(Node_To_Replace
);
9468 -- If the operation has been rewritten into a call, which may get
9469 -- subsequently an explicit dereference, preserve the type on the
9470 -- original node (selected component or indexed component) for
9471 -- subsequent legality tests, e.g. Is_Variable. which examines
9472 -- the original node.
9474 if Nkind
(Node_To_Replace
) = N_Function_Call
then
9476 (Original_Node
(Node_To_Replace
), Etype
(Node_To_Replace
));
9479 end Complete_Object_Operation
;
9481 ----------------------
9482 -- Report_Ambiguity --
9483 ----------------------
9485 procedure Report_Ambiguity
(Op
: Entity_Id
) is
9486 Access_Actual
: constant Boolean :=
9487 Is_Access_Type
(Etype
(Prefix
(N
)));
9488 Access_Formal
: Boolean := False;
9491 Error_Msg_Sloc
:= Sloc
(Op
);
9493 if Present
(First_Formal
(Op
)) then
9494 Access_Formal
:= Is_Access_Type
(Etype
(First_Formal
(Op
)));
9497 if Access_Formal
and then not Access_Actual
then
9498 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9500 ("\possible interpretation "
9501 & "(inherited, with implicit 'Access) #", N
);
9504 ("\possible interpretation (with implicit 'Access) #", N
);
9507 elsif not Access_Formal
and then Access_Actual
then
9508 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9510 ("\possible interpretation "
9511 & "(inherited, with implicit dereference) #", N
);
9514 ("\possible interpretation (with implicit dereference) #", N
);
9518 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9519 Error_Msg_N
("\possible interpretation (inherited)#", N
);
9521 Error_Msg_N
-- CODEFIX
9522 ("\possible interpretation#", N
);
9525 end Report_Ambiguity
;
9527 --------------------------------
9528 -- Transform_Object_Operation --
9529 --------------------------------
9531 procedure Transform_Object_Operation
9532 (Call_Node
: out Node_Id
;
9533 Node_To_Replace
: out Node_Id
)
9535 Dummy
: constant Node_Id
:= New_Copy
(Obj
);
9536 -- Placeholder used as a first parameter in the call, replaced
9537 -- eventually by the proper object.
9539 Parent_Node
: constant Node_Id
:= Parent
(N
);
9545 -- Common case covering 1) Call to a procedure and 2) Call to a
9546 -- function that has some additional actuals.
9548 if Nkind
(Parent_Node
) in N_Subprogram_Call
9550 -- N is a selected component node containing the name of the
9551 -- subprogram. If N is not the name of the parent node we must
9552 -- not replace the parent node by the new construct. This case
9553 -- occurs when N is a parameterless call to a subprogram that
9554 -- is an actual parameter of a call to another subprogram. For
9556 -- Some_Subprogram (..., Obj.Operation, ...)
9558 and then N
= Name
(Parent_Node
)
9560 Node_To_Replace
:= Parent_Node
;
9562 Actuals
:= Parameter_Associations
(Parent_Node
);
9564 if Present
(Actuals
) then
9565 Prepend
(Dummy
, Actuals
);
9567 Actuals
:= New_List
(Dummy
);
9570 if Nkind
(Parent_Node
) = N_Procedure_Call_Statement
then
9572 Make_Procedure_Call_Statement
(Loc
,
9573 Name
=> New_Copy
(Subprog
),
9574 Parameter_Associations
=> Actuals
);
9578 Make_Function_Call
(Loc
,
9579 Name
=> New_Copy
(Subprog
),
9580 Parameter_Associations
=> Actuals
);
9583 -- Before analysis, a function call appears as an indexed component
9584 -- if there are no named associations.
9586 elsif Nkind
(Parent_Node
) = N_Indexed_Component
9587 and then N
= Prefix
(Parent_Node
)
9589 Node_To_Replace
:= Parent_Node
;
9590 Actuals
:= Expressions
(Parent_Node
);
9592 Actual
:= First
(Actuals
);
9593 while Present
(Actual
) loop
9598 Prepend
(Dummy
, Actuals
);
9601 Make_Function_Call
(Loc
,
9602 Name
=> New_Copy
(Subprog
),
9603 Parameter_Associations
=> Actuals
);
9605 -- Parameterless call: Obj.F is rewritten as F (Obj)
9608 Node_To_Replace
:= N
;
9611 Make_Function_Call
(Loc
,
9612 Name
=> New_Copy
(Subprog
),
9613 Parameter_Associations
=> New_List
(Dummy
));
9615 end Transform_Object_Operation
;
9617 ------------------------------
9618 -- Try_Class_Wide_Operation --
9619 ------------------------------
9621 function Try_Class_Wide_Operation
9622 (Call_Node
: Node_Id
;
9623 Node_To_Replace
: Node_Id
) return Boolean
9625 Anc_Type
: Entity_Id
;
9626 Matching_Op
: Entity_Id
:= Empty
;
9629 procedure Traverse_Homonyms
9630 (Anc_Type
: Entity_Id
;
9631 Error
: out Boolean);
9632 -- Traverse the homonym chain of the subprogram searching for those
9633 -- homonyms whose first formal has the Anc_Type's class-wide type,
9634 -- or an anonymous access type designating the class-wide type. If
9635 -- an ambiguity is detected, then Error is set to True.
9637 procedure Traverse_Interfaces
9638 (Anc_Type
: Entity_Id
;
9639 Error
: out Boolean);
9640 -- Traverse the list of interfaces, if any, associated with Anc_Type
9641 -- and search for acceptable class-wide homonyms associated with each
9642 -- interface. If an ambiguity is detected, then Error is set to True.
9644 -----------------------
9645 -- Traverse_Homonyms --
9646 -----------------------
9648 procedure Traverse_Homonyms
9649 (Anc_Type
: Entity_Id
;
9650 Error
: out Boolean)
9652 function First_Formal_Match
9653 (Subp_Id
: Entity_Id
;
9654 Typ
: Entity_Id
) return Boolean;
9655 -- Predicate to verify that the first foramal of class-wide
9656 -- subprogram Subp_Id matches type Typ of the prefix.
9658 ------------------------
9659 -- First_Formal_Match --
9660 ------------------------
9662 function First_Formal_Match
9663 (Subp_Id
: Entity_Id
;
9664 Typ
: Entity_Id
) return Boolean
9666 Ctrl
: constant Entity_Id
:= First_Formal
(Subp_Id
);
9672 (Base_Type
(Etype
(Ctrl
)) = Typ
9674 (Ekind
(Etype
(Ctrl
)) = E_Anonymous_Access_Type
9676 Base_Type
(Designated_Type
(Etype
(Ctrl
))) =
9678 end First_Formal_Match
;
9682 CW_Typ
: constant Entity_Id
:= Class_Wide_Type
(Anc_Type
);
9684 Candidate
: Entity_Id
;
9685 -- If homonym is a renaming, examine the renamed program
9691 -- Start of processing for Traverse_Homonyms
9696 -- Find a non-hidden operation whose first parameter is of the
9697 -- class-wide type, a subtype thereof, or an anonymous access
9698 -- to same. If in an instance, the operation can be considered
9699 -- even if hidden (it may be hidden because the instantiation
9700 -- is expanded after the containing package has been analyzed).
9701 -- If the subprogram is a generic actual in an enclosing instance,
9702 -- it appears as a renaming that is a candidate interpretation as
9705 Hom
:= Current_Entity
(Subprog
);
9706 while Present
(Hom
) loop
9707 if Ekind
(Hom
) in E_Procedure | E_Function
9708 and then Present
(Renamed_Entity
(Hom
))
9709 and then Is_Generic_Actual_Subprogram
(Hom
)
9710 and then In_Open_Scopes
(Scope
(Hom
))
9712 Candidate
:= Renamed_Entity
(Hom
);
9717 if Ekind
(Candidate
) in E_Function | E_Procedure
9718 and then (not Is_Hidden
(Candidate
) or else In_Instance
)
9719 and then Scope
(Candidate
) = Scope
(Base_Type
(Anc_Type
))
9720 and then First_Formal_Match
(Candidate
, CW_Typ
)
9722 -- If the context is a procedure call, ignore functions
9723 -- in the name of the call.
9725 if Ekind
(Candidate
) = E_Function
9726 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
9727 and then N
= Name
(Parent
(N
))
9731 -- If the context is a function call, ignore procedures
9732 -- in the name of the call.
9734 elsif Ekind
(Candidate
) = E_Procedure
9735 and then Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
9740 Set_Etype
(Call_Node
, Any_Type
);
9741 Set_Is_Overloaded
(Call_Node
, False);
9744 if No
(Matching_Op
) then
9745 Hom_Ref
:= New_Occurrence_Of
(Candidate
, Sloc
(Subprog
));
9747 Set_Etype
(Call_Node
, Any_Type
);
9748 Set_Name
(Call_Node
, Hom_Ref
);
9749 Set_Parent
(Call_Node
, Parent
(Node_To_Replace
));
9754 Report
=> Report_Error
,
9756 Skip_First
=> True);
9759 Valid_Candidate
(Success
, Call_Node
, Candidate
);
9765 Report
=> Report_Error
,
9767 Skip_First
=> True);
9769 -- The same operation may be encountered on two homonym
9770 -- traversals, before and after looking at interfaces.
9771 -- Check for this case before reporting a real ambiguity.
9774 (Valid_Candidate
(Success
, Call_Node
, Candidate
))
9775 and then Nkind
(Call_Node
) /= N_Function_Call
9776 and then Candidate
/= Matching_Op
9778 Error_Msg_NE
("ambiguous call to&", N
, Hom
);
9779 Report_Ambiguity
(Matching_Op
);
9780 Report_Ambiguity
(Hom
);
9781 Check_Ambiguous_Aggregate
(New_Call_Node
);
9789 Hom
:= Homonym
(Hom
);
9791 end Traverse_Homonyms
;
9793 -------------------------
9794 -- Traverse_Interfaces --
9795 -------------------------
9797 procedure Traverse_Interfaces
9798 (Anc_Type
: Entity_Id
;
9799 Error
: out Boolean)
9801 Intface_List
: constant List_Id
:=
9802 Abstract_Interface_List
(Anc_Type
);
9808 Intface
:= First
(Intface_List
);
9809 while Present
(Intface
) loop
9811 -- Look for acceptable class-wide homonyms associated with the
9814 Traverse_Homonyms
(Etype
(Intface
), Error
);
9820 -- Continue the search by looking at each of the interface's
9821 -- associated interface ancestors.
9823 Traverse_Interfaces
(Etype
(Intface
), Error
);
9831 end Traverse_Interfaces
;
9833 -- Start of processing for Try_Class_Wide_Operation
9836 -- If we are searching only for conflicting class-wide subprograms
9837 -- then initialize directly Matching_Op with the target entity.
9839 if CW_Test_Only
then
9840 Matching_Op
:= Entity
(Selector_Name
(N
));
9843 -- Loop through ancestor types (including interfaces), traversing
9844 -- the homonym chain of the subprogram, trying out those homonyms
9845 -- whose first formal has the class-wide type of the ancestor, or
9846 -- an anonymous access type designating the class-wide type.
9848 Anc_Type
:= Obj_Type
;
9850 -- Look for a match among homonyms associated with the ancestor
9852 Traverse_Homonyms
(Anc_Type
, Error
);
9858 -- Continue the search for matches among homonyms associated with
9859 -- any interfaces implemented by the ancestor.
9861 Traverse_Interfaces
(Anc_Type
, Error
);
9867 exit when Etype
(Anc_Type
) = Anc_Type
;
9868 Anc_Type
:= Etype
(Anc_Type
);
9871 if Present
(Matching_Op
) then
9872 Set_Etype
(Call_Node
, Etype
(Matching_Op
));
9875 return Present
(Matching_Op
);
9876 end Try_Class_Wide_Operation
;
9878 -----------------------------------
9879 -- Try_One_Prefix_Interpretation --
9880 -----------------------------------
9882 procedure Try_One_Prefix_Interpretation
(T
: Entity_Id
) is
9883 Prev_Obj_Type
: constant Entity_Id
:= Obj_Type
;
9884 -- If the interpretation does not have a valid candidate type,
9885 -- preserve current value of Obj_Type for subsequent errors.
9890 if Is_Access_Type
(Obj_Type
) then
9891 Obj_Type
:= Designated_Type
(Obj_Type
);
9895 in E_Private_Subtype | E_Record_Subtype_With_Private
9897 Obj_Type
:= Base_Type
(Obj_Type
);
9900 if Is_Class_Wide_Type
(Obj_Type
) then
9901 Obj_Type
:= Etype
(Class_Wide_Type
(Obj_Type
));
9904 -- The type may have be obtained through a limited_with clause,
9905 -- in which case the primitive operations are available on its
9906 -- nonlimited view. If still incomplete, retrieve full view.
9908 if Ekind
(Obj_Type
) = E_Incomplete_Type
9909 and then From_Limited_With
(Obj_Type
)
9910 and then Has_Non_Limited_View
(Obj_Type
)
9912 Obj_Type
:= Get_Full_View
(Non_Limited_View
(Obj_Type
));
9915 -- If the object is not tagged, or the type is still an incomplete
9916 -- type, this is not a prefixed call. Restore the previous type as
9917 -- the current one is not a legal candidate.
9919 -- Extension feature: Calls with prefixed views are also supported
9920 -- for untagged types, so skip the early return when extensions are
9921 -- enabled, unless the type doesn't have a primitive operations list
9922 -- (such as in the case of predefined types).
9924 if (not Is_Tagged_Type
(Obj_Type
)
9926 (not (Core_Extensions_Allowed
or Allow_Extensions
)
9927 or else No
(Primitive_Operations
(Obj_Type
))))
9928 or else Is_Incomplete_Type
(Obj_Type
)
9930 Obj_Type
:= Prev_Obj_Type
;
9935 Dup_Call_Node
: constant Node_Id
:= New_Copy
(New_Call_Node
);
9937 Prim_Result
: Boolean := False;
9940 if not CW_Test_Only
then
9942 Try_Primitive_Operation
9943 (Call_Node
=> New_Call_Node
,
9944 Node_To_Replace
=> Node_To_Replace
);
9946 -- Extension feature: In the case where the prefix is of an
9947 -- access type, and a primitive wasn't found for the designated
9948 -- type, then if the access type has primitives we attempt a
9949 -- prefixed call using one of its primitives. (It seems that
9950 -- this isn't quite right to give preference to the designated
9951 -- type in the case where both the access and designated types
9952 -- have homographic prefixed-view operations that could result
9953 -- in an ambiguity, but handling properly may be tricky. ???)
9955 if (Core_Extensions_Allowed
or Allow_Extensions
)
9956 and then not Prim_Result
9957 and then Is_Named_Access_Type
(Prev_Obj_Type
)
9958 and then Present
(Direct_Primitive_Operations
(Prev_Obj_Type
))
9960 -- Temporarily reset Obj_Type to the original access type
9962 Obj_Type
:= Prev_Obj_Type
;
9965 Try_Primitive_Operation
9966 (Call_Node
=> New_Call_Node
,
9967 Node_To_Replace
=> Node_To_Replace
);
9969 -- Restore Obj_Type to the designated type (is this really
9970 -- necessary, or should it only be done when Prim_Result is
9973 Obj_Type
:= Designated_Type
(Obj_Type
);
9977 -- Check if there is a class-wide subprogram covering the
9978 -- primitive. This check must be done even if a candidate
9979 -- was found in order to report ambiguous calls.
9981 if not Prim_Result
then
9983 Try_Class_Wide_Operation
9984 (Call_Node
=> New_Call_Node
,
9985 Node_To_Replace
=> Node_To_Replace
);
9987 -- If we found a primitive we search for class-wide subprograms
9988 -- using a duplicate of the call node (done to avoid missing its
9989 -- decoration if there is no ambiguity).
9993 Try_Class_Wide_Operation
9994 (Call_Node
=> Dup_Call_Node
,
9995 Node_To_Replace
=> Node_To_Replace
);
9998 end Try_One_Prefix_Interpretation
;
10000 -----------------------------
10001 -- Try_Primitive_Operation --
10002 -----------------------------
10004 function Try_Primitive_Operation
10005 (Call_Node
: Node_Id
;
10006 Node_To_Replace
: Node_Id
) return Boolean
10009 Prim_Op
: Entity_Id
;
10010 Matching_Op
: Entity_Id
:= Empty
;
10011 Prim_Op_Ref
: Node_Id
:= Empty
;
10013 Corr_Type
: Entity_Id
:= Empty
;
10014 -- If the prefix is a synchronized type, the controlling type of
10015 -- the primitive operation is the corresponding record type, else
10016 -- this is the object type itself.
10018 Success
: Boolean := False;
10020 function Collect_Generic_Type_Ops
(T
: Entity_Id
) return Elist_Id
;
10021 -- For tagged types the candidate interpretations are found in
10022 -- the list of primitive operations of the type and its ancestors.
10023 -- For formal tagged types we have to find the operations declared
10024 -- in the same scope as the type (including in the generic formal
10025 -- part) because the type itself carries no primitive operations,
10026 -- except for formal derived types that inherit the operations of
10027 -- the parent and progenitors.
10029 -- If the context is a generic subprogram body, the generic formals
10030 -- are visible by name, but are not in the entity list of the
10031 -- subprogram because that list starts with the subprogram formals.
10032 -- We retrieve the candidate operations from the generic declaration.
10034 function Extended_Primitive_Ops
(T
: Entity_Id
) return Elist_Id
;
10035 -- Prefix notation can also be used on operations that are not
10036 -- primitives of the type, but are declared in the same immediate
10037 -- declarative part, which can only mean the corresponding package
10038 -- body (see RM 4.1.3 (9.2/3)). If we are in that body we extend the
10039 -- list of primitives with body operations with the same name that
10040 -- may be candidates, so that Try_Primitive_Operations can examine
10041 -- them if no real primitive is found.
10043 function Is_Private_Overriding
(Op
: Entity_Id
) return Boolean;
10044 -- An operation that overrides an inherited operation in the private
10045 -- part of its package may be hidden, but if the inherited operation
10046 -- is visible a direct call to it will dispatch to the private one,
10047 -- which is therefore a valid candidate.
10049 function Names_Match
10050 (Obj_Type
: Entity_Id
;
10051 Prim_Op
: Entity_Id
;
10052 Subprog
: Entity_Id
) return Boolean;
10053 -- Return True if the names of Prim_Op and Subprog match. If Obj_Type
10054 -- is a protected type then compare also the original name of Prim_Op
10055 -- with the name of Subprog (since the expander may have added a
10056 -- prefix to its original name --see Exp_Ch9.Build_Selected_Name).
10058 function Valid_First_Argument_Of
(Op
: Entity_Id
) return Boolean;
10059 -- Verify that the prefix, dereferenced if need be, is a valid
10060 -- controlling argument in a call to Op. The remaining actuals
10061 -- are checked in the subsequent call to Analyze_One_Call.
10063 ------------------------------
10064 -- Collect_Generic_Type_Ops --
10065 ------------------------------
10067 function Collect_Generic_Type_Ops
(T
: Entity_Id
) return Elist_Id
is
10068 Bas
: constant Entity_Id
:= Base_Type
(T
);
10069 Candidates
: constant Elist_Id
:= New_Elmt_List
;
10071 Formal
: Entity_Id
;
10073 procedure Check_Candidate
;
10074 -- The operation is a candidate if its first parameter is a
10075 -- controlling operand of the desired type.
10077 -----------------------
10078 -- Check_Candidate; --
10079 -----------------------
10081 procedure Check_Candidate
is
10083 Formal
:= First_Formal
(Subp
);
10085 if Present
(Formal
)
10086 and then Is_Controlling_Formal
(Formal
)
10088 (Base_Type
(Etype
(Formal
)) = Bas
10090 (Is_Access_Type
(Etype
(Formal
))
10091 and then Designated_Type
(Etype
(Formal
)) = Bas
))
10093 Append_Elmt
(Subp
, Candidates
);
10095 end Check_Candidate
;
10097 -- Start of processing for Collect_Generic_Type_Ops
10100 if Is_Derived_Type
(T
) then
10101 return Primitive_Operations
(T
);
10103 elsif Ekind
(Scope
(T
)) in E_Procedure | E_Function
then
10105 -- Scan the list of generic formals to find subprograms
10106 -- that may have a first controlling formal of the type.
10108 if Nkind
(Unit_Declaration_Node
(Scope
(T
))) =
10109 N_Generic_Subprogram_Declaration
10116 First
(Generic_Formal_Declarations
10117 (Unit_Declaration_Node
(Scope
(T
))));
10118 while Present
(Decl
) loop
10119 if Nkind
(Decl
) in N_Formal_Subprogram_Declaration
then
10120 Subp
:= Defining_Entity
(Decl
);
10131 -- Scan the list of entities declared in the same scope as
10132 -- the type. In general this will be an open scope, given that
10133 -- the call we are analyzing can only appear within a generic
10134 -- declaration or body (either the one that declares T, or a
10137 -- For a subtype representing a generic actual type, go to the
10140 if Is_Generic_Actual_Type
(T
) then
10141 Subp
:= First_Entity
(Scope
(Base_Type
(T
)));
10143 Subp
:= First_Entity
(Scope
(T
));
10146 while Present
(Subp
) loop
10147 if Is_Overloadable
(Subp
) then
10151 Next_Entity
(Subp
);
10156 end Collect_Generic_Type_Ops
;
10158 ----------------------------
10159 -- Extended_Primitive_Ops --
10160 ----------------------------
10162 function Extended_Primitive_Ops
(T
: Entity_Id
) return Elist_Id
is
10163 Type_Scope
: constant Entity_Id
:= Scope
(T
);
10164 Op_List
: Elist_Id
:= Primitive_Operations
(T
);
10166 if Is_Package_Or_Generic_Package
(Type_Scope
)
10167 and then ((In_Package_Body
(Type_Scope
)
10168 and then In_Open_Scopes
(Type_Scope
)) or else In_Instance_Body
)
10170 -- Retrieve list of declarations of package body if possible
10173 The_Body
: constant Node_Id
:=
10174 Corresponding_Body
(Unit_Declaration_Node
(Type_Scope
));
10176 if Present
(The_Body
) then
10178 Body_Decls
: constant List_Id
:=
10179 Declarations
(Unit_Declaration_Node
(The_Body
));
10180 Op_Found
: Boolean := False;
10181 Op
: Entity_Id
:= Current_Entity
(Subprog
);
10183 while Present
(Op
) loop
10184 if Comes_From_Source
(Op
)
10185 and then Is_Overloadable
(Op
)
10187 -- Exclude overriding primitive operations of a
10188 -- type extension declared in the package body,
10189 -- to prevent duplicates in extended list.
10191 and then not Is_Primitive
(Op
)
10192 and then Is_List_Member
10193 (Unit_Declaration_Node
(Op
))
10194 and then List_Containing
10195 (Unit_Declaration_Node
(Op
)) = Body_Decls
10197 if not Op_Found
then
10198 -- Copy list of primitives so it is not
10199 -- affected for other uses.
10201 Op_List
:= New_Copy_Elist
(Op_List
);
10205 Append_Elmt
(Op
, Op_List
);
10208 Op
:= Homonym
(Op
);
10216 end Extended_Primitive_Ops
;
10218 ---------------------------
10219 -- Is_Private_Overriding --
10220 ---------------------------
10222 function Is_Private_Overriding
(Op
: Entity_Id
) return Boolean is
10223 Visible_Op
: Entity_Id
;
10226 -- The subprogram may be overloaded with both visible and private
10227 -- entities with the same name. We have to scan the chain of
10228 -- homonyms to determine whether there is a previous implicit
10229 -- declaration in the same scope that is overridden by the
10230 -- private candidate.
10232 Visible_Op
:= Homonym
(Op
);
10233 while Present
(Visible_Op
) loop
10234 if Scope
(Op
) /= Scope
(Visible_Op
) then
10237 elsif not Comes_From_Source
(Visible_Op
)
10238 and then Alias
(Visible_Op
) = Op
10240 -- If Visible_Op or what it overrides is not hidden, then we
10241 -- have found what we're looking for.
10243 if not Is_Hidden
(Visible_Op
)
10244 or else not Is_Hidden
(Overridden_Operation
(Op
))
10250 Visible_Op
:= Homonym
(Visible_Op
);
10254 end Is_Private_Overriding
;
10260 function Names_Match
10261 (Obj_Type
: Entity_Id
;
10262 Prim_Op
: Entity_Id
;
10263 Subprog
: Entity_Id
) return Boolean is
10265 -- Common case: exact match
10267 if Chars
(Prim_Op
) = Chars
(Subprog
) then
10270 -- For protected type primitives the expander may have built the
10271 -- name of the dispatching primitive prepending the type name to
10272 -- avoid conflicts with the name of the protected subprogram (see
10273 -- Exp_Ch9.Build_Selected_Name).
10275 elsif Is_Protected_Type
(Obj_Type
) then
10277 Present
(Original_Protected_Subprogram
(Prim_Op
))
10278 and then Chars
(Original_Protected_Subprogram
(Prim_Op
)) =
10281 -- In an instance, the selector name may be a generic actual that
10282 -- renames a primitive operation of the type of the prefix.
10284 elsif In_Instance
and then Present
(Current_Entity
(Subprog
)) then
10286 Subp
: constant Entity_Id
:= Current_Entity
(Subprog
);
10289 and then Is_Subprogram
(Subp
)
10290 and then Present
(Renamed_Entity
(Subp
))
10291 and then Is_Generic_Actual_Subprogram
(Subp
)
10292 and then Chars
(Renamed_Entity
(Subp
)) = Chars
(Prim_Op
)
10302 -----------------------------
10303 -- Valid_First_Argument_Of --
10304 -----------------------------
10306 function Valid_First_Argument_Of
(Op
: Entity_Id
) return Boolean is
10307 Typ
: Entity_Id
:= Etype
(First_Formal
(Op
));
10310 if Is_Concurrent_Type
(Typ
)
10311 and then Present
(Corresponding_Record_Type
(Typ
))
10313 Typ
:= Corresponding_Record_Type
(Typ
);
10316 -- Simple case. Object may be a subtype of the tagged type or may
10317 -- be the corresponding record of a synchronized type.
10319 return Obj_Type
= Typ
10320 or else Base_Type
(Obj_Type
) = Base_Type
(Typ
)
10321 or else Corr_Type
= Typ
10323 -- Object may be of a derived type whose parent has unknown
10324 -- discriminants, in which case the type matches the underlying
10325 -- record view of its base.
10328 (Has_Unknown_Discriminants
(Typ
)
10329 and then Typ
= Underlying_Record_View
(Base_Type
(Obj_Type
)))
10331 -- Prefix can be dereferenced
10334 (Is_Access_Type
(Corr_Type
)
10335 and then Designated_Type
(Corr_Type
) = Typ
)
10337 -- Formal is an access parameter, for which the object can
10338 -- provide an access.
10341 (Ekind
(Typ
) = E_Anonymous_Access_Type
10343 Base_Type
(Designated_Type
(Typ
)) = Base_Type
(Corr_Type
));
10344 end Valid_First_Argument_Of
;
10346 -- Start of processing for Try_Primitive_Operation
10349 -- Look for subprograms in the list of primitive operations. The name
10350 -- must be identical, and the kind of call indicates the expected
10351 -- kind of operation (function or procedure). If the type is a
10352 -- (tagged) synchronized type, the primitive ops are attached to the
10353 -- corresponding record (base) type.
10355 if Is_Concurrent_Type
(Obj_Type
) then
10356 if Present
(Corresponding_Record_Type
(Obj_Type
)) then
10357 Corr_Type
:= Base_Type
(Corresponding_Record_Type
(Obj_Type
));
10358 Elmt
:= First_Elmt
(Primitive_Operations
(Corr_Type
));
10360 Corr_Type
:= Obj_Type
;
10361 Elmt
:= First_Elmt
(Collect_Generic_Type_Ops
(Obj_Type
));
10364 elsif not Is_Generic_Type
(Obj_Type
) then
10365 Corr_Type
:= Obj_Type
;
10366 Elmt
:= First_Elmt
(Extended_Primitive_Ops
(Obj_Type
));
10369 Corr_Type
:= Obj_Type
;
10370 Elmt
:= First_Elmt
(Collect_Generic_Type_Ops
(Obj_Type
));
10373 while Present
(Elmt
) loop
10374 Prim_Op
:= Node
(Elmt
);
10376 if Names_Match
(Obj_Type
, Prim_Op
, Subprog
)
10377 and then Present
(First_Formal
(Prim_Op
))
10378 and then Valid_First_Argument_Of
(Prim_Op
)
10380 (Nkind
(Call_Node
) = N_Function_Call
)
10382 (Ekind
(Prim_Op
) = E_Function
)
10384 -- Ada 2005 (AI-251): If this primitive operation corresponds
10385 -- to an immediate ancestor interface there is no need to add
10386 -- it to the list of interpretations; the corresponding aliased
10387 -- primitive is also in this list of primitive operations and
10388 -- will be used instead.
10390 if (Present
(Interface_Alias
(Prim_Op
))
10391 and then Is_Ancestor
(Find_Dispatching_Type
10392 (Alias
(Prim_Op
)), Corr_Type
))
10394 -- Do not consider hidden primitives unless the type is in an
10395 -- open scope or we are within an instance, where visibility
10396 -- is known to be correct, or else if this is an overriding
10397 -- operation in the private part for an inherited operation.
10399 or else (Is_Hidden
(Prim_Op
)
10400 and then not Is_Immediately_Visible
(Obj_Type
)
10401 and then not In_Instance
10402 and then not Is_Private_Overriding
(Prim_Op
))
10407 Set_Etype
(Call_Node
, Any_Type
);
10408 Set_Is_Overloaded
(Call_Node
, False);
10410 if No
(Matching_Op
) then
10411 Prim_Op_Ref
:= New_Occurrence_Of
(Prim_Op
, Sloc
(Subprog
));
10412 Candidate
:= Prim_Op
;
10414 Set_Parent
(Call_Node
, Parent
(Node_To_Replace
));
10416 Set_Name
(Call_Node
, Prim_Op_Ref
);
10422 Report
=> Report_Error
,
10423 Success
=> Success
,
10424 Skip_First
=> True);
10426 Matching_Op
:= Valid_Candidate
(Success
, Call_Node
, Prim_Op
);
10428 -- More than one interpretation, collect for subsequent
10429 -- disambiguation. If this is a procedure call and there
10430 -- is another match, report ambiguity now.
10436 Report
=> Report_Error
,
10437 Success
=> Success
,
10438 Skip_First
=> True);
10440 if Present
(Valid_Candidate
(Success
, Call_Node
, Prim_Op
))
10441 and then Nkind
(Call_Node
) /= N_Function_Call
10443 Error_Msg_NE
("ambiguous call to&", N
, Prim_Op
);
10444 Report_Ambiguity
(Matching_Op
);
10445 Report_Ambiguity
(Prim_Op
);
10446 Check_Ambiguous_Aggregate
(Call_Node
);
10456 if Present
(Matching_Op
) then
10457 Set_Etype
(Call_Node
, Etype
(Matching_Op
));
10460 return Present
(Matching_Op
);
10461 end Try_Primitive_Operation
;
10463 ---------------------
10464 -- Valid_Candidate --
10465 ---------------------
10467 function Valid_Candidate
10468 (Success
: Boolean;
10470 Subp
: Entity_Id
) return Entity_Id
10472 Arr_Type
: Entity_Id
;
10473 Comp_Type
: Entity_Id
;
10476 -- If the subprogram is a valid interpretation, record it in global
10477 -- variable Subprog, to collect all possible overloadings.
10480 if Subp
/= Entity
(Subprog
) then
10481 Add_One_Interp
(Subprog
, Subp
, Etype
(Subp
));
10485 -- If the call may be an indexed call, retrieve component type of
10486 -- resulting expression, and add possible interpretation.
10489 Comp_Type
:= Empty
;
10491 if Nkind
(Call
) = N_Function_Call
10492 and then Nkind
(Parent
(N
)) = N_Indexed_Component
10493 and then Needs_One_Actual
(Subp
)
10495 if Is_Array_Type
(Etype
(Subp
)) then
10496 Arr_Type
:= Etype
(Subp
);
10498 elsif Is_Access_Type
(Etype
(Subp
))
10499 and then Is_Array_Type
(Designated_Type
(Etype
(Subp
)))
10501 Arr_Type
:= Designated_Type
(Etype
(Subp
));
10505 if Present
(Arr_Type
) then
10507 -- Verify that the actuals (excluding the object) match the types
10515 Actual
:= Next
(First_Actual
(Call
));
10516 Index
:= First_Index
(Arr_Type
);
10517 while Present
(Actual
) and then Present
(Index
) loop
10518 if not Has_Compatible_Type
(Actual
, Etype
(Index
)) then
10523 Next_Actual
(Actual
);
10524 Next_Index
(Index
);
10528 and then No
(Index
)
10529 and then Present
(Arr_Type
)
10531 Comp_Type
:= Component_Type
(Arr_Type
);
10535 if Present
(Comp_Type
)
10536 and then Etype
(Subprog
) /= Comp_Type
10538 Add_One_Interp
(Subprog
, Subp
, Comp_Type
);
10542 if Etype
(Call
) /= Any_Type
then
10547 end Valid_Candidate
;
10549 -- Start of processing for Try_Object_Operation
10552 Analyze_Expression
(Obj
);
10554 -- Analyze the actuals if node is known to be a subprogram call
10556 if Is_Subprg_Call
and then N
= Name
(Parent
(N
)) then
10557 Actual
:= First
(Parameter_Associations
(Parent
(N
)));
10558 while Present
(Actual
) loop
10559 Analyze_Expression
(Actual
);
10564 -- Build a subprogram call node, using a copy of Obj as its first
10565 -- actual. This is a placeholder, to be replaced by an explicit
10566 -- dereference when needed.
10568 Transform_Object_Operation
10569 (Call_Node
=> New_Call_Node
,
10570 Node_To_Replace
=> Node_To_Replace
);
10572 Set_Etype
(New_Call_Node
, Any_Type
);
10573 Set_Etype
(Subprog
, Any_Type
);
10574 Set_Parent
(New_Call_Node
, Parent
(Node_To_Replace
));
10576 if not Is_Overloaded
(Obj
) then
10577 Try_One_Prefix_Interpretation
(Obj_Type
);
10584 Get_First_Interp
(Obj
, I
, It
);
10585 while Present
(It
.Nam
) loop
10586 Try_One_Prefix_Interpretation
(It
.Typ
);
10587 Get_Next_Interp
(I
, It
);
10592 if Etype
(New_Call_Node
) /= Any_Type
then
10594 -- No need to complete the tree transformations if we are only
10595 -- searching for conflicting class-wide subprograms
10597 if CW_Test_Only
then
10600 Complete_Object_Operation
10601 (Call_Node
=> New_Call_Node
,
10602 Node_To_Replace
=> Node_To_Replace
);
10606 elsif Present
(Candidate
) then
10608 -- The argument list is not type correct. Re-analyze with error
10609 -- reporting enabled, and use one of the possible candidates.
10610 -- In All_Errors_Mode, re-analyze all failed interpretations.
10612 if All_Errors_Mode
then
10613 Report_Error
:= True;
10614 if Try_Primitive_Operation
10615 (Call_Node
=> New_Call_Node
,
10616 Node_To_Replace
=> Node_To_Replace
)
10619 Try_Class_Wide_Operation
10620 (Call_Node
=> New_Call_Node
,
10621 Node_To_Replace
=> Node_To_Replace
)
10628 (N
=> New_Call_Node
,
10631 Success
=> Success
,
10632 Skip_First
=> True);
10634 -- The error may hot have been reported yet for overloaded
10635 -- prefixed calls, depending on the non-matching candidate,
10636 -- in which case provide a concise error now.
10638 if Serious_Errors_Detected
= 0 then
10640 ("cannot resolve prefixed call to primitive operation of&",
10645 -- No need for further errors
10650 -- There was no candidate operation, but Analyze_Selected_Component
10651 -- may continue the analysis so we need to undo the change possibly
10652 -- made to the Parent of N earlier by Transform_Object_Operation.
10655 Parent_Node
: constant Node_Id
:= Parent
(N
);
10658 if Node_To_Replace
= Parent_Node
then
10659 Remove
(First
(Parameter_Associations
(New_Call_Node
)));
10661 (Parameter_Associations
(New_Call_Node
), Parent_Node
);
10667 end Try_Object_Operation
;
10669 -------------------------
10670 -- Unresolved_Operator --
10671 -------------------------
10673 procedure Unresolved_Operator
(N
: Node_Id
) is
10674 L
: constant Node_Id
:=
10675 (if Nkind
(N
) in N_Binary_Op
then Left_Opnd
(N
) else Empty
);
10676 R
: constant Node_Id
:= Right_Opnd
(N
);
10681 -- Note that in the following messages, if the operand is overloaded we
10682 -- choose an arbitrary type to complain about, but that is probably more
10683 -- useful than not giving a type at all.
10685 if Nkind
(N
) in N_Unary_Op
then
10686 Error_Msg_Node_2
:= Etype
(R
);
10687 Error_Msg_N
("operator& not defined for}", N
);
10689 elsif Nkind
(N
) in N_Binary_Op
then
10690 if not Is_Overloaded
(L
)
10691 and then not Is_Overloaded
(R
)
10692 and then Base_Type
(Etype
(L
)) = Base_Type
(Etype
(R
))
10694 Error_Msg_Node_2
:= First_Subtype
(Etype
(R
));
10695 Error_Msg_N
("there is no applicable operator& for}", N
);
10698 -- Another attempt to find a fix: one of the candidate
10699 -- interpretations may not be use-visible. This has
10700 -- already been checked for predefined operators, so
10701 -- we examine only user-defined functions.
10703 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
10705 while Present
(Op_Id
) loop
10706 if Ekind
(Op_Id
) /= E_Operator
10707 and then Is_Overloadable
(Op_Id
)
10708 and then not Is_Immediately_Visible
(Op_Id
)
10709 and then not In_Use
(Scope
(Op_Id
))
10710 and then not Is_Abstract_Subprogram
(Op_Id
)
10711 and then not Is_Hidden
(Op_Id
)
10712 and then Ekind
(Scope
(Op_Id
)) = E_Package
10713 and then Has_Compatible_Type
(L
, Etype
(First_Formal
(Op_Id
)))
10714 and then Present
(Next_Formal
(First_Formal
(Op_Id
)))
10716 Has_Compatible_Type
10717 (R
, Etype
(Next_Formal
(First_Formal
(Op_Id
))))
10719 Error_Msg_N
("no legal interpretation for operator&", N
);
10720 Error_Msg_NE
("\use clause on& would make operation legal",
10725 Op_Id
:= Homonym
(Op_Id
);
10729 Error_Msg_N
("invalid operand types for operator&", N
);
10731 if Nkind
(N
) /= N_Op_Concat
then
10732 Error_Msg_NE
("\left operand has}!", N
, Etype
(L
));
10733 Error_Msg_NE
("\right operand has}!", N
, Etype
(R
));
10735 -- For multiplication and division operators with
10736 -- a fixed-point operand and an integer operand,
10737 -- indicate that the integer operand should be of
10740 if Nkind
(N
) in N_Op_Multiply | N_Op_Divide
10741 and then Is_Fixed_Point_Type
(Etype
(L
))
10742 and then Is_Integer_Type
(Etype
(R
))
10744 Error_Msg_N
("\convert right operand to `Integer`", N
);
10746 elsif Nkind
(N
) = N_Op_Multiply
10747 and then Is_Fixed_Point_Type
(Etype
(R
))
10748 and then Is_Integer_Type
(Etype
(L
))
10750 Error_Msg_N
("\convert left operand to `Integer`", N
);
10753 -- For concatenation operators it is more difficult to
10754 -- determine which is the wrong operand. It is worth
10755 -- flagging explicitly an access type, for those who
10756 -- might think that a dereference happens here.
10758 elsif Is_Access_Type
(Etype
(L
)) then
10759 Error_Msg_N
("\left operand is access type", N
);
10761 elsif Is_Access_Type
(Etype
(R
)) then
10762 Error_Msg_N
("\right operand is access type", N
);
10767 end Unresolved_Operator
;
10773 procedure wpo
(T
: Entity_Id
) is
10778 if not Is_Tagged_Type
(T
) then
10782 E
:= First_Elmt
(Primitive_Operations
(Base_Type
(T
)));
10783 while Present
(E
) loop
10785 Write_Int
(Int
(Op
));
10786 Write_Str
(" === ");
10787 Write_Name
(Chars
(Op
));
10788 Write_Str
(" in ");
10789 Write_Name
(Chars
(Scope
(Op
)));