1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2023, 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
722 Not_Null_Check
: constant Node_Id
:=
723 Make_Raise_Constraint_Error
(Sloc
(E
),
724 Reason
=> CE_Null_Not_Allowed
);
727 if Expander_Active
then
728 Insert_Action
(N
, Not_Null_Check
);
729 Analyze
(Not_Null_Check
);
731 elsif Warn_On_Ada_2012_Compatibility
then
733 ("null value not allowed here in Ada 2012?y?", E
);
738 -- Check for missing initialization. Skip this check if the allocator
739 -- is made for a special return object or if we already had errors on
740 -- analyzing the allocator since, in that case, these are very likely
743 if not Is_Definite_Subtype
(Type_Id
)
744 and then not For_Special_Return_Object
(N
)
745 and then Serious_Errors_Detected
= Sav_Errs
747 if Is_Class_Wide_Type
(Type_Id
) then
749 ("initialization required in class-wide allocation", N
);
752 if Ada_Version
< Ada_2005
753 and then Is_Limited_Type
(Type_Id
)
755 Error_Msg_N
("unconstrained allocation not allowed", N
);
757 if Is_Array_Type
(Type_Id
) then
759 ("\constraint with array bounds required", N
);
761 elsif Has_Unknown_Discriminants
(Type_Id
) then
764 else pragma Assert
(Has_Discriminants
(Type_Id
));
766 ("\constraint with discriminant values required", N
);
769 -- Limited Ada 2005 and general nonlimited case.
770 -- This is an error, except in the case of an
771 -- uninitialized allocator that is generated
772 -- for a build-in-place function return of a
773 -- discriminated but compile-time-known-size
777 if Is_Rewrite_Substitution
(N
)
778 and then Nkind
(Original_Node
(N
)) = N_Allocator
781 Qual
: constant Node_Id
:=
782 Expression
(Original_Node
(N
));
784 (Nkind
(Qual
) = N_Qualified_Expression
);
785 Call
: constant Node_Id
:= Expression
(Qual
);
787 (Is_Expanded_Build_In_Place_Call
(Call
));
794 ("uninitialized unconstrained allocation not "
797 if Is_Array_Type
(Type_Id
) then
799 ("\qualified expression or constraint with "
800 & "array bounds required", N
);
802 elsif Has_Unknown_Discriminants
(Type_Id
) then
803 Error_Msg_N
("\qualified expression required", N
);
805 else pragma Assert
(Has_Discriminants
(Type_Id
));
807 ("\qualified expression or constraint with "
808 & "discriminant values required", N
);
816 if Is_Abstract_Type
(Type_Id
) then
817 Error_Msg_N
("cannot allocate abstract object", E
);
820 Set_Etype
(N
, Acc_Type
);
822 -- If this is an allocator for the return stack, then no restriction may
823 -- be violated since it's just a low-level access to the primary stack.
825 if Nkind
(Parent
(N
)) = N_Object_Declaration
826 and then Is_Entity_Name
(Object_Definition
(Parent
(N
)))
827 and then Is_Access_Type
(Entity
(Object_Definition
(Parent
(N
))))
830 Pool
: constant Entity_Id
:=
831 Associated_Storage_Pool
832 (Root_Type
(Entity
(Object_Definition
(Parent
(N
)))));
835 if Present
(Pool
) and then Is_RTE
(Pool
, RE_RS_Pool
) then
841 if Has_Task
(Designated_Type
(Acc_Type
)) then
842 Check_Restriction
(No_Tasking
, N
);
843 Check_Restriction
(Max_Tasks
, N
);
844 Check_Restriction
(No_Task_Allocators
, N
);
847 -- Check restriction against dynamically allocated protected objects
849 if Has_Protected
(Designated_Type
(Acc_Type
)) then
850 Check_Restriction
(No_Protected_Type_Allocators
, N
);
853 -- AI05-0013-1: No_Nested_Finalization forbids allocators if the access
854 -- type is nested, and the designated type needs finalization. The rule
855 -- is conservative in that class-wide types need finalization.
857 if Needs_Finalization
(Designated_Type
(Acc_Type
))
858 and then not Is_Library_Level_Entity
(Acc_Type
)
860 Check_Restriction
(No_Nested_Finalization
, N
);
863 -- Check that an allocator of a nested access type doesn't create a
864 -- protected object when restriction No_Local_Protected_Objects applies.
866 if Has_Protected
(Designated_Type
(Acc_Type
))
867 and then not Is_Library_Level_Entity
(Acc_Type
)
869 Check_Restriction
(No_Local_Protected_Objects
, N
);
872 -- Likewise for No_Local_Timing_Events
874 if Has_Timing_Event
(Designated_Type
(Acc_Type
))
875 and then not Is_Library_Level_Entity
(Acc_Type
)
877 Check_Restriction
(No_Local_Timing_Events
, N
);
880 -- If the No_Streams restriction is set, check that the type of the
881 -- object is not, and does not contain, any subtype derived from
882 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
883 -- Has_Stream just for efficiency reasons. There is no point in
884 -- spending time on a Has_Stream check if the restriction is not set.
886 if Restriction_Check_Required
(No_Streams
) then
887 if Has_Stream
(Designated_Type
(Acc_Type
)) then
888 Check_Restriction
(No_Streams
, N
);
892 if not Is_Library_Level_Entity
(Acc_Type
) then
893 Check_Restriction
(No_Local_Allocators
, N
);
897 if Serious_Errors_Detected
> Sav_Errs
then
898 Set_Error_Posted
(N
);
899 Set_Etype
(N
, Any_Type
);
901 end Analyze_Allocator
;
903 ---------------------------
904 -- Analyze_Arithmetic_Op --
905 ---------------------------
907 procedure Analyze_Arithmetic_Op
(N
: Node_Id
) is
908 L
: constant Node_Id
:= Left_Opnd
(N
);
909 R
: constant Node_Id
:= Right_Opnd
(N
);
914 Set_Etype
(N
, Any_Type
);
915 Candidate_Type
:= Empty
;
917 Analyze_Expression
(L
);
918 Analyze_Expression
(R
);
920 -- If the entity is already set, the node is the instantiation of a
921 -- generic node with a non-local reference, or was manufactured by a
922 -- call to Make_Op_xxx. In either case the entity is known to be valid,
923 -- and we do not need to collect interpretations, instead we just get
924 -- the single possible interpretation.
926 if Present
(Entity
(N
)) then
929 if Ekind
(Op_Id
) = E_Operator
then
930 Find_Arithmetic_Types
(L
, R
, Op_Id
, N
);
932 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
935 -- Entity is not already set, so we do need to collect interpretations
938 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
939 while Present
(Op_Id
) loop
940 if Ekind
(Op_Id
) = E_Operator
941 and then Present
(Next_Entity
(First_Entity
(Op_Id
)))
943 Find_Arithmetic_Types
(L
, R
, Op_Id
, N
);
945 -- The following may seem superfluous, because an operator cannot
946 -- be generic, but this ignores the cleverness of the author of
949 elsif Is_Overloadable
(Op_Id
) then
950 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
953 Op_Id
:= Homonym
(Op_Id
);
958 Check_Function_Writable_Actuals
(N
);
959 end Analyze_Arithmetic_Op
;
965 -- Function, procedure, and entry calls are checked here. The Name in
966 -- the call may be overloaded. The actuals have been analyzed and may
967 -- themselves be overloaded. On exit from this procedure, the node N
968 -- may have zero, one or more interpretations. In the first case an
969 -- error message is produced. In the last case, the node is flagged
970 -- as overloaded and the interpretations are collected in All_Interp.
972 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
973 -- the type-checking is similar to that of other calls.
975 procedure Analyze_Call
(N
: Node_Id
) is
976 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
977 Loc
: constant Source_Ptr
:= Sloc
(N
);
981 Nam_Ent
: Entity_Id
:= Empty
;
982 Success
: Boolean := False;
984 Deref
: Boolean := False;
985 -- Flag indicates whether an interpretation of the prefix is a
986 -- parameterless call that returns an access_to_subprogram.
988 procedure Check_Writable_Actuals
(N
: Node_Id
);
989 -- If the call has out or in-out parameters then mark its outermost
990 -- enclosing construct as a node on which the writable actuals check
991 -- must be performed.
993 function Name_Denotes_Function
return Boolean;
994 -- If the type of the name is an access to subprogram, this may be the
995 -- type of a name, or the return type of the function being called. If
996 -- the name is not an entity then it can denote a protected function.
997 -- Until we distinguish Etype from Return_Type, we must use this routine
998 -- to resolve the meaning of the name in the call.
1000 procedure No_Interpretation
;
1001 -- Output error message when no valid interpretation exists
1003 ----------------------------
1004 -- Check_Writable_Actuals --
1005 ----------------------------
1007 -- The identification of conflicts in calls to functions with writable
1008 -- actuals is performed in the analysis phase of the front end to ensure
1009 -- that it reports exactly the same errors compiling with and without
1010 -- expansion enabled. It is performed in two stages:
1012 -- 1) When a call to a function with out-mode parameters is found,
1013 -- we climb to the outermost enclosing construct that can be
1014 -- evaluated in arbitrary order and we mark it with the flag
1017 -- 2) When the analysis of the marked node is complete, we traverse
1018 -- its decorated subtree searching for conflicts (see function
1019 -- Sem_Util.Check_Function_Writable_Actuals).
1021 -- The unique exception to this general rule is for aggregates, since
1022 -- their analysis is performed by the front end in the resolution
1023 -- phase. For aggregates we do not climb to their enclosing construct:
1024 -- we restrict the analysis to the subexpressions initializing the
1025 -- aggregate components.
1027 -- This implies that the analysis of expressions containing aggregates
1028 -- is not complete, since there may be conflicts on writable actuals
1029 -- involving subexpressions of the enclosing logical or arithmetic
1030 -- expressions. However, we cannot wait and perform the analysis when
1031 -- the whole subtree is resolved, since the subtrees may be transformed,
1032 -- thus adding extra complexity and computation cost to identify and
1033 -- report exactly the same errors compiling with and without expansion
1036 procedure Check_Writable_Actuals
(N
: Node_Id
) is
1038 if Comes_From_Source
(N
)
1039 and then Present
(Get_Subprogram_Entity
(N
))
1040 and then Has_Out_Or_In_Out_Parameter
(Get_Subprogram_Entity
(N
))
1042 -- For procedures and entries there is no need to climb since
1043 -- we only need to check if the actuals of this call invoke
1044 -- functions whose out-mode parameters overlap.
1046 if Nkind
(N
) /= N_Function_Call
then
1047 Set_Check_Actuals
(N
);
1049 -- For calls to functions we climb to the outermost enclosing
1050 -- construct where the out-mode actuals of this function may
1051 -- introduce conflicts.
1055 Outermost
: Node_Id
:= Empty
; -- init to avoid warning
1059 while Present
(P
) loop
1060 -- For object declarations we can climb to the node from
1061 -- its object definition branch or from its initializing
1062 -- expression. We prefer to mark the child node as the
1063 -- outermost construct to avoid adding further complexity
1064 -- to the routine that will later take care of
1065 -- performing the writable actuals check.
1067 if Has_Arbitrary_Evaluation_Order
(Nkind
(P
))
1068 and then Nkind
(P
) not in
1069 N_Assignment_Statement | N_Object_Declaration
1074 -- Avoid climbing more than needed
1076 exit when Stop_Subtree_Climbing
(Nkind
(P
))
1077 or else (Nkind
(P
) = N_Range
1079 Nkind
(Parent
(P
)) not in N_In | N_Not_In
);
1084 Set_Check_Actuals
(Outermost
);
1088 end Check_Writable_Actuals
;
1090 ---------------------------
1091 -- Name_Denotes_Function --
1092 ---------------------------
1094 function Name_Denotes_Function
return Boolean is
1096 if Is_Entity_Name
(Nam
) then
1097 return Ekind
(Entity
(Nam
)) = E_Function
;
1098 elsif Nkind
(Nam
) = N_Selected_Component
then
1099 return Ekind
(Entity
(Selector_Name
(Nam
))) = E_Function
;
1103 end Name_Denotes_Function
;
1105 -----------------------
1106 -- No_Interpretation --
1107 -----------------------
1109 procedure No_Interpretation
is
1110 L
: constant Boolean := Is_List_Member
(N
);
1111 K
: constant Node_Kind
:= Nkind
(Parent
(N
));
1114 -- If the node is in a list whose parent is not an expression then it
1115 -- must be an attempted procedure call.
1117 if L
and then K
not in N_Subexpr
then
1118 if Ekind
(Entity
(Nam
)) = E_Generic_Procedure
then
1120 ("must instantiate generic procedure& before call",
1123 Error_Msg_N
("procedure or entry name expected", Nam
);
1126 -- Check for tasking cases where only an entry call will do
1129 and then K
in N_Entry_Call_Alternative | N_Triggering_Alternative
1131 Error_Msg_N
("entry name expected", Nam
);
1133 -- Otherwise give general error message
1136 Error_Msg_N
("invalid prefix in call", Nam
);
1138 end No_Interpretation
;
1140 -- Start of processing for Analyze_Call
1143 -- Initialize the type of the result of the call to the error type,
1144 -- which will be reset if the type is successfully resolved.
1146 Set_Etype
(N
, Any_Type
);
1150 if not Is_Overloaded
(Nam
) then
1152 -- Only one interpretation to check
1154 if Ekind
(Etype
(Nam
)) = E_Subprogram_Type
then
1155 Nam_Ent
:= Etype
(Nam
);
1157 -- If the prefix is an access_to_subprogram, this may be an indirect
1158 -- call. This is the case if the name in the call is not an entity
1159 -- name, or if it is a function name in the context of a procedure
1160 -- call. In this latter case, we have a call to a parameterless
1161 -- function that returns a pointer_to_procedure which is the entity
1162 -- being called. Finally, F (X) may be a call to a parameterless
1163 -- function that returns a pointer to a function with parameters.
1164 -- Note that if F returns an access-to-subprogram whose designated
1165 -- type is an array, F (X) cannot be interpreted as an indirect call
1166 -- through the result of the call to F.
1168 elsif Is_Access_Subprogram_Type
(Base_Type
(Etype
(Nam
)))
1170 (not Name_Denotes_Function
1171 or else Nkind
(N
) = N_Procedure_Call_Statement
1173 (Nkind
(Parent
(N
)) /= N_Explicit_Dereference
1174 and then Is_Entity_Name
(Nam
)
1175 and then No
(First_Formal
(Entity
(Nam
)))
1177 Is_Array_Type
(Etype
(Designated_Type
(Etype
(Nam
))))
1178 and then Present
(Actuals
)))
1180 Nam_Ent
:= Designated_Type
(Etype
(Nam
));
1181 Insert_Explicit_Dereference
(Nam
);
1183 -- Selected component case. Simple entry or protected operation,
1184 -- where the entry name is given by the selector name.
1186 elsif Nkind
(Nam
) = N_Selected_Component
then
1187 Nam_Ent
:= Entity
(Selector_Name
(Nam
));
1189 if Ekind
(Nam_Ent
) not in E_Entry
1194 Error_Msg_N
("name in call is not a callable entity", Nam
);
1195 Set_Etype
(N
, Any_Type
);
1199 -- If the name is an Indexed component, it can be a call to a member
1200 -- of an entry family. The prefix must be a selected component whose
1201 -- selector is the entry. Analyze_Procedure_Call normalizes several
1202 -- kinds of call into this form.
1204 elsif Nkind
(Nam
) = N_Indexed_Component
then
1205 if Nkind
(Prefix
(Nam
)) = N_Selected_Component
then
1206 Nam_Ent
:= Entity
(Selector_Name
(Prefix
(Nam
)));
1208 Error_Msg_N
("name in call is not a callable entity", Nam
);
1209 Set_Etype
(N
, Any_Type
);
1213 elsif not Is_Entity_Name
(Nam
) then
1214 Error_Msg_N
("name in call is not a callable entity", Nam
);
1215 Set_Etype
(N
, Any_Type
);
1219 Nam_Ent
:= Entity
(Nam
);
1221 -- If not overloadable, this may be a generalized indexing
1222 -- operation with named associations. Rewrite again as an
1223 -- indexed component and analyze as container indexing.
1225 if not Is_Overloadable
(Nam_Ent
) then
1227 (Find_Value_Of_Aspect
1228 (Etype
(Nam_Ent
), Aspect_Constant_Indexing
))
1231 Make_Indexed_Component
(Sloc
(N
),
1233 Expressions
=> Parameter_Associations
(N
)));
1235 if Try_Container_Indexing
(N
, Nam
, Expressions
(N
)) then
1249 -- Operations generated for RACW stub types are called only through
1250 -- dispatching, and can never be the static interpretation of a call.
1252 if Is_RACW_Stub_Type_Operation
(Nam_Ent
) then
1257 Analyze_One_Call
(N
, Nam_Ent
, True, Success
);
1259 -- If the nonoverloaded interpretation is a call to an abstract
1260 -- nondispatching operation, then flag an error and return.
1262 if Is_Overloadable
(Nam_Ent
)
1263 and then Is_Abstract_Subprogram
(Nam_Ent
)
1264 and then not Is_Dispatching_Operation
(Nam_Ent
)
1266 Nondispatching_Call_To_Abstract_Operation
(N
, Nam_Ent
);
1270 -- If this is an indirect call, the return type of the access_to
1271 -- subprogram may be an incomplete type. At the point of the call,
1272 -- use the full type if available, and at the same time update the
1273 -- return type of the access_to_subprogram.
1276 and then Nkind
(Nam
) = N_Explicit_Dereference
1277 and then Ekind
(Etype
(N
)) = E_Incomplete_Type
1278 and then Present
(Full_View
(Etype
(N
)))
1280 Set_Etype
(N
, Full_View
(Etype
(N
)));
1281 Set_Etype
(Nam_Ent
, Etype
(N
));
1287 -- An overloaded selected component must denote overloaded operations
1288 -- of a concurrent type. The interpretations are attached to the
1289 -- simple name of those operations.
1291 if Nkind
(Nam
) = N_Selected_Component
then
1292 Nam
:= Selector_Name
(Nam
);
1295 Get_First_Interp
(Nam
, X
, It
);
1296 while Present
(It
.Nam
) loop
1300 -- Name may be call that returns an access to subprogram, or more
1301 -- generally an overloaded expression one of whose interpretations
1302 -- yields an access to subprogram. If the name is an entity, we do
1303 -- not dereference, because the node is a call that returns the
1304 -- access type: note difference between f(x), where the call may
1305 -- return an access subprogram type, and f(x)(y), where the type
1306 -- returned by the call to f is implicitly dereferenced to analyze
1309 if Is_Access_Type
(Nam_Ent
) then
1310 Nam_Ent
:= Designated_Type
(Nam_Ent
);
1312 elsif Is_Access_Type
(Etype
(Nam_Ent
))
1314 (not Is_Entity_Name
(Nam
)
1315 or else Nkind
(N
) = N_Procedure_Call_Statement
)
1316 and then Ekind
(Designated_Type
(Etype
(Nam_Ent
)))
1319 Nam_Ent
:= Designated_Type
(Etype
(Nam_Ent
));
1321 if Is_Entity_Name
(Nam
) then
1326 -- If the call has been rewritten from a prefixed call, the first
1327 -- parameter has been analyzed, but may need a subsequent
1328 -- dereference, so skip its analysis now.
1330 if Is_Rewrite_Substitution
(N
)
1331 and then Nkind
(Original_Node
(N
)) = Nkind
(N
)
1332 and then Nkind
(Name
(N
)) /= Nkind
(Name
(Original_Node
(N
)))
1333 and then Present
(Parameter_Associations
(N
))
1334 and then Present
(Etype
(First
(Parameter_Associations
(N
))))
1337 (N
, Nam_Ent
, False, Success
, Skip_First
=> True);
1339 Analyze_One_Call
(N
, Nam_Ent
, False, Success
);
1342 -- If the interpretation succeeds, mark the proper type of the
1343 -- prefix (any valid candidate will do). If not, remove the
1344 -- candidate interpretation. If this is a parameterless call
1345 -- on an anonymous access to subprogram, X is a variable with
1346 -- an access discriminant D, the entity in the interpretation is
1347 -- D, so rewrite X as X.D.all.
1351 and then Nkind
(Parent
(N
)) /= N_Explicit_Dereference
1353 if Ekind
(It
.Nam
) = E_Discriminant
1354 and then Has_Implicit_Dereference
(It
.Nam
)
1357 Make_Explicit_Dereference
(Loc
,
1359 Make_Selected_Component
(Loc
,
1361 New_Occurrence_Of
(Entity
(Nam
), Loc
),
1363 New_Occurrence_Of
(It
.Nam
, Loc
))));
1369 Set_Entity
(Nam
, It
.Nam
);
1370 Insert_Explicit_Dereference
(Nam
);
1371 Set_Etype
(Nam
, Nam_Ent
);
1375 Set_Etype
(Nam
, It
.Typ
);
1378 elsif Nkind
(Name
(N
)) in N_Function_Call | N_Selected_Component
1383 Get_Next_Interp
(X
, It
);
1386 -- If the name is the result of a function call, it can only be a
1387 -- call to a function returning an access to subprogram. Insert
1388 -- explicit dereference.
1390 if Nkind
(Nam
) = N_Function_Call
then
1391 Insert_Explicit_Dereference
(Nam
);
1394 if Etype
(N
) = Any_Type
then
1396 -- None of the interpretations is compatible with the actuals
1398 Diagnose_Call
(N
, Nam
);
1400 -- Special checks for uninstantiated put routines
1402 if Nkind
(N
) = N_Procedure_Call_Statement
1403 and then Is_Entity_Name
(Nam
)
1404 and then Chars
(Nam
) = Name_Put
1405 and then List_Length
(Actuals
) = 1
1408 Arg
: constant Node_Id
:= First
(Actuals
);
1412 if Nkind
(Arg
) = N_Parameter_Association
then
1413 Typ
:= Etype
(Explicit_Actual_Parameter
(Arg
));
1418 if Is_Signed_Integer_Type
(Typ
) then
1420 ("possible missing instantiation of "
1421 & "'Text_'I'O.'Integer_'I'O!", Nam
);
1423 elsif Is_Modular_Integer_Type
(Typ
) then
1425 ("possible missing instantiation of "
1426 & "'Text_'I'O.'Modular_'I'O!", Nam
);
1428 elsif Is_Floating_Point_Type
(Typ
) then
1430 ("possible missing instantiation of "
1431 & "'Text_'I'O.'Float_'I'O!", Nam
);
1433 elsif Is_Ordinary_Fixed_Point_Type
(Typ
) then
1435 ("possible missing instantiation of "
1436 & "'Text_'I'O.'Fixed_'I'O!", Nam
);
1438 elsif Is_Decimal_Fixed_Point_Type
(Typ
) then
1440 ("possible missing instantiation of "
1441 & "'Text_'I'O.'Decimal_'I'O!", Nam
);
1443 elsif Is_Enumeration_Type
(Typ
) then
1445 ("possible missing instantiation of "
1446 & "'Text_'I'O.'Enumeration_'I'O!", Nam
);
1451 elsif not Is_Overloaded
(N
)
1452 and then Is_Entity_Name
(Nam
)
1454 -- Resolution yields a single interpretation. Verify that the
1455 -- reference has capitalization consistent with the declaration.
1457 Set_Entity_With_Checks
(Nam
, Entity
(Nam
));
1458 Generate_Reference
(Entity
(Nam
), Nam
);
1460 Set_Etype
(Nam
, Etype
(Entity
(Nam
)));
1462 Remove_Abstract_Operations
(N
);
1466 -- Check the accessibility level for actuals for explicitly aliased
1467 -- formals when a function call appears within a return statement.
1468 -- This is only checked if the enclosing subprogram Comes_From_Source,
1469 -- to avoid issuing errors on calls occurring in wrapper subprograms
1470 -- (for example, where the call is part of an expression of an aspect
1471 -- associated with a wrapper, such as Pre'Class).
1473 if Nkind
(N
) = N_Function_Call
1474 and then Comes_From_Source
(N
)
1475 and then Present
(Nam_Ent
)
1476 and then In_Return_Value
(N
)
1477 and then Comes_From_Source
(Current_Subprogram
)
1483 Act
:= First_Actual
(N
);
1484 Form
:= First_Formal
(Nam_Ent
);
1486 while Present
(Form
) and then Present
(Act
) loop
1487 -- Check whether the formal is aliased and if the accessibility
1488 -- level of the actual is deeper than the accessibility level
1489 -- of the enclosing subprogram to which the current return
1490 -- statement applies.
1492 -- Should we be checking Is_Entity_Name on Act? Won't this miss
1495 if Is_Explicitly_Aliased
(Form
)
1496 and then Is_Entity_Name
(Act
)
1497 and then Static_Accessibility_Level
1498 (Act
, Zero_On_Dynamic_Level
)
1499 > Subprogram_Access_Level
(Current_Subprogram
)
1501 Error_Msg_N
("actual for explicitly aliased formal is too"
1502 & " short lived", Act
);
1511 if Ada_Version
>= Ada_2012
then
1513 -- Check if the call contains a function with writable actuals
1515 Check_Writable_Actuals
(N
);
1517 -- If found and the outermost construct that can be evaluated in
1518 -- an arbitrary order is precisely this call, then check all its
1521 Check_Function_Writable_Actuals
(N
);
1523 -- The return type of the function may be incomplete. This can be
1524 -- the case if the type is a generic formal, or a limited view. It
1525 -- can also happen when the function declaration appears before the
1526 -- full view of the type (which is legal in Ada 2012) and the call
1527 -- appears in a different unit, in which case the incomplete view
1528 -- must be replaced with the full view (or the nonlimited view)
1529 -- to prevent subsequent type errors. Note that the usual install/
1530 -- removal of limited_with clauses is not sufficient to handle this
1531 -- case, because the limited view may have been captured in another
1532 -- compilation unit that defines the current function.
1534 if Is_Incomplete_Type
(Etype
(N
)) then
1535 if Present
(Full_View
(Etype
(N
))) then
1536 if Is_Entity_Name
(Nam
) then
1537 Set_Etype
(Nam
, Full_View
(Etype
(N
)));
1538 Set_Etype
(Entity
(Nam
), Full_View
(Etype
(N
)));
1541 Set_Etype
(N
, Full_View
(Etype
(N
)));
1543 -- If the call is within a thunk, the nonlimited view should be
1544 -- analyzed eventually (see also Analyze_Return_Type).
1546 elsif From_Limited_With
(Etype
(N
))
1547 and then Present
(Non_Limited_View
(Etype
(N
)))
1549 (Ekind
(Non_Limited_View
(Etype
(N
))) /= E_Incomplete_Type
1550 or else Is_Thunk
(Current_Scope
))
1552 Set_Etype
(N
, Non_Limited_View
(Etype
(N
)));
1554 -- If there is no completion for the type, this may be because
1555 -- there is only a limited view of it and there is nothing in
1556 -- the context of the current unit that has required a regular
1557 -- compilation of the unit containing the type. We recognize
1558 -- this unusual case by the fact that unit is not analyzed.
1559 -- Note that the call being analyzed is in a different unit from
1560 -- the function declaration, and nothing indicates that the type
1561 -- is a limited view.
1563 elsif Ekind
(Scope
(Etype
(N
))) = E_Package
1564 and then Present
(Limited_View
(Scope
(Etype
(N
))))
1565 and then not Analyzed
(Unit_Declaration_Node
(Scope
(Etype
(N
))))
1568 ("cannot call function that returns limited view of}",
1572 ("\there must be a regular with_clause for package & in the "
1573 & "current unit, or in some unit in its context",
1574 N
, Scope
(Etype
(N
)));
1576 Set_Etype
(N
, Any_Type
);
1582 -----------------------------
1583 -- Analyze_Case_Expression --
1584 -----------------------------
1586 procedure Analyze_Case_Expression
(N
: Node_Id
) is
1587 Expr
: constant Node_Id
:= Expression
(N
);
1588 First_Alt
: constant Node_Id
:= First
(Alternatives
(N
));
1590 First_Expr
: Node_Id
:= Empty
;
1591 -- First expression in the case where there is some type information
1592 -- available, i.e. there is not Any_Type everywhere, which can happen
1593 -- because of some error.
1595 Second_Expr
: Node_Id
:= Empty
;
1596 -- Second expression as above
1598 Wrong_Alt
: Node_Id
:= Empty
;
1599 -- For error reporting
1601 procedure Non_Static_Choice_Error
(Choice
: Node_Id
);
1602 -- Error routine invoked by the generic instantiation below when
1603 -- the case expression has a non static choice.
1605 procedure Check_Next_Expression
(T
: Entity_Id
; Alt
: Node_Id
);
1606 -- Check one interpretation of the next expression with type T
1608 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
; Alt
: Node_Id
);
1609 -- Check first expression with type T1 and next expression with type T2
1611 package Case_Choices_Analysis
is new
1612 Generic_Analyze_Choices
1613 (Process_Associated_Node
=> No_OP
);
1614 use Case_Choices_Analysis
;
1616 package Case_Choices_Checking
is new
1617 Generic_Check_Choices
1618 (Process_Empty_Choice
=> No_OP
,
1619 Process_Non_Static_Choice
=> Non_Static_Choice_Error
,
1620 Process_Associated_Node
=> No_OP
);
1621 use Case_Choices_Checking
;
1623 -----------------------------
1624 -- Non_Static_Choice_Error --
1625 -----------------------------
1627 procedure Non_Static_Choice_Error
(Choice
: Node_Id
) is
1629 Flag_Non_Static_Expr
1630 ("choice given in case expression is not static!", Choice
);
1631 end Non_Static_Choice_Error
;
1633 ---------------------------
1634 -- Check_Next_Expression --
1635 ---------------------------
1637 procedure Check_Next_Expression
(T
: Entity_Id
; Alt
: Node_Id
) is
1638 Next_Expr
: constant Node_Id
:= Expression
(Alt
);
1644 if Next_Expr
= First_Expr
then
1645 Check_Next_Expression
(T
, Next
(Alt
));
1649 -- Loop through the interpretations of the next expression
1651 if not Is_Overloaded
(Next_Expr
) then
1652 Check_Expression_Pair
(T
, Etype
(Next_Expr
), Alt
);
1655 Get_First_Interp
(Next_Expr
, I
, It
);
1656 while Present
(It
.Typ
) loop
1657 Check_Expression_Pair
(T
, It
.Typ
, Alt
);
1658 Get_Next_Interp
(I
, It
);
1661 end Check_Next_Expression
;
1663 ---------------------------
1664 -- Check_Expression_Pair --
1665 ---------------------------
1667 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
; Alt
: Node_Id
) is
1668 Next_Expr
: constant Node_Id
:= Expression
(Alt
);
1673 if Covers
(T1
=> T1
, T2
=> T2
)
1674 or else Covers
(T1
=> T2
, T2
=> T1
)
1676 T
:= Specific_Type
(T1
, T2
);
1678 elsif Is_User_Defined_Literal
(First_Expr
, T2
) then
1681 elsif Is_User_Defined_Literal
(Next_Expr
, T1
) then
1685 T
:= Possible_Type_For_Conditional_Expression
(T1
, T2
);
1693 if Present
(Next
(Alt
)) then
1694 Check_Next_Expression
(T
, Next
(Alt
));
1696 Add_One_Interp
(N
, T
, T
);
1698 end Check_Expression_Pair
;
1703 Exp_Type
: Entity_Id
;
1704 Exp_Btype
: Entity_Id
;
1707 Others_Present
: Boolean;
1709 -- Start of processing for Analyze_Case_Expression
1712 Analyze_And_Resolve
(Expr
, Any_Discrete
);
1713 Check_Unset_Reference
(Expr
);
1714 Exp_Type
:= Etype
(Expr
);
1715 Exp_Btype
:= Base_Type
(Exp_Type
);
1717 Set_Etype
(N
, Any_Type
);
1720 while Present
(Alt
) loop
1721 if Error_Posted
(Expression
(Alt
)) then
1725 Analyze_Expression
(Expression
(Alt
));
1727 if Etype
(Expression
(Alt
)) /= Any_Type
then
1728 if No
(First_Expr
) then
1729 First_Expr
:= Expression
(Alt
);
1731 elsif No
(Second_Expr
) then
1732 Second_Expr
:= Expression
(Alt
);
1739 -- Get our initial type from the first expression for which we got some
1740 -- useful type information from the expression.
1742 if No
(First_Expr
) then
1746 -- The expression must be of a discrete type which must be determinable
1747 -- independently of the context in which the expression occurs, but
1748 -- using the fact that the expression must be of a discrete type.
1749 -- Moreover, the type this expression must not be a character literal
1750 -- (which is always ambiguous).
1752 -- If error already reported by Resolve, nothing more to do
1754 if Exp_Btype
= Any_Discrete
or else Exp_Btype
= Any_Type
then
1757 -- Special case message for character literal
1759 elsif Exp_Btype
= Any_Character
then
1761 ("character literal as case expression is ambiguous", Expr
);
1765 -- If the case expression is a formal object of mode in out, then
1766 -- treat it as having a nonstatic subtype by forcing use of the base
1767 -- type (which has to get passed to Check_Case_Choices below). Also
1768 -- use base type when the case expression is parenthesized.
1770 if Paren_Count
(Expr
) > 0
1771 or else (Is_Entity_Name
(Expr
)
1772 and then Ekind
(Entity
(Expr
)) = E_Generic_In_Out_Parameter
)
1774 Exp_Type
:= Exp_Btype
;
1777 -- The case expression alternatives cover the range of a static subtype
1778 -- subject to aspect Static_Predicate. Do not check the choices when the
1779 -- case expression has not been fully analyzed yet because this may lead
1782 if Is_OK_Static_Subtype
(Exp_Type
)
1783 and then Has_Static_Predicate_Aspect
(Exp_Type
)
1784 and then In_Spec_Expression
1788 -- Call Analyze_Choices and Check_Choices to do the rest of the work
1791 Analyze_Choices
(Alternatives
(N
), Exp_Type
);
1792 Check_Choices
(N
, Alternatives
(N
), Exp_Type
, Others_Present
);
1794 if Exp_Type
= Universal_Integer
and then not Others_Present
then
1796 ("case on universal integer requires OTHERS choice", Expr
);
1801 -- RM 4.5.7(10/3): If the case_expression is the operand of a type
1802 -- conversion, the type of the case_expression is the target type
1803 -- of the conversion.
1805 if Nkind
(Parent
(N
)) = N_Type_Conversion
then
1806 Set_Etype
(N
, Etype
(Parent
(N
)));
1810 -- Loop through the interpretations of the first expression and check
1811 -- the other expressions if present.
1813 if not Is_Overloaded
(First_Expr
) then
1814 if Present
(Second_Expr
) then
1815 Check_Next_Expression
(Etype
(First_Expr
), First_Alt
);
1817 Set_Etype
(N
, Etype
(First_Expr
));
1821 Get_First_Interp
(First_Expr
, I
, It
);
1822 while Present
(It
.Typ
) loop
1823 if Present
(Second_Expr
) then
1824 Check_Next_Expression
(It
.Typ
, First_Alt
);
1826 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
1829 Get_Next_Interp
(I
, It
);
1833 -- If no possible interpretation has been found, the type of the wrong
1834 -- alternative doesn't match any interpretation of the FIRST expression.
1836 if Etype
(N
) = Any_Type
and then Present
(Wrong_Alt
) then
1837 Second_Expr
:= Expression
(Wrong_Alt
);
1839 if Is_Overloaded
(First_Expr
) then
1840 if Is_Overloaded
(Second_Expr
) then
1842 ("no interpretation compatible with those of previous "
1847 ("type incompatible with interpretations of previous "
1851 ("\this alternative has}!",
1853 Etype
(Second_Expr
));
1857 if Is_Overloaded
(Second_Expr
) then
1859 ("no interpretation compatible with type of previous "
1863 ("\previous alternative has}!",
1865 Etype
(First_Expr
));
1868 ("type incompatible with that of previous alternative",
1871 ("\previous alternative has}!",
1873 Etype
(First_Expr
));
1875 ("\this alternative has}!",
1877 Etype
(Second_Expr
));
1881 end Analyze_Case_Expression
;
1883 ---------------------------
1884 -- Analyze_Concatenation --
1885 ---------------------------
1887 procedure Analyze_Concatenation
(N
: Node_Id
) is
1889 -- We wish to avoid deep recursion, because concatenations are often
1890 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1891 -- operands nonrecursively until we find something that is not a
1892 -- concatenation (A in this case), or has already been analyzed. We
1893 -- analyze that, and then walk back up the tree following Parent
1894 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1895 -- work at each level. The Parent pointers allow us to avoid recursion,
1896 -- and thus avoid running out of memory.
1902 Candidate_Type
:= Empty
;
1904 -- The following code is equivalent to:
1906 -- Set_Etype (N, Any_Type);
1907 -- Analyze_Expression (Left_Opnd (N));
1908 -- Analyze_Concatenation_Rest (N);
1910 -- where the Analyze_Expression call recurses back here if the left
1911 -- operand is a concatenation.
1913 -- Walk down left operands
1916 Set_Etype
(NN
, Any_Type
);
1917 L
:= Left_Opnd
(NN
);
1918 exit when Nkind
(L
) /= N_Op_Concat
or else Analyzed
(L
);
1922 -- Now (given the above example) NN is A&B and L is A
1924 -- First analyze L ...
1926 Analyze_Expression
(L
);
1928 -- ... then walk NN back up until we reach N (where we started), calling
1929 -- Analyze_Concatenation_Rest along the way.
1932 Analyze_Concatenation_Rest
(NN
);
1936 end Analyze_Concatenation
;
1938 --------------------------------
1939 -- Analyze_Concatenation_Rest --
1940 --------------------------------
1942 -- If the only one-dimensional array type in scope is String,
1943 -- this is the resulting type of the operation. Otherwise there
1944 -- will be a concatenation operation defined for each user-defined
1945 -- one-dimensional array.
1947 procedure Analyze_Concatenation_Rest
(N
: Node_Id
) is
1948 L
: constant Node_Id
:= Left_Opnd
(N
);
1949 R
: constant Node_Id
:= Right_Opnd
(N
);
1950 Op_Id
: Entity_Id
:= Entity
(N
);
1955 Analyze_Expression
(R
);
1957 -- If the entity is present, the node appears in an instance, and
1958 -- denotes a predefined concatenation operation. The resulting type is
1959 -- obtained from the arguments when possible. If the arguments are
1960 -- aggregates, the array type and the concatenation type must be
1963 if Present
(Op_Id
) then
1964 if Ekind
(Op_Id
) = E_Operator
then
1965 LT
:= Base_Type
(Etype
(L
));
1966 RT
:= Base_Type
(Etype
(R
));
1968 if Is_Array_Type
(LT
)
1969 and then (RT
= LT
or else RT
= Base_Type
(Component_Type
(LT
)))
1971 Add_One_Interp
(N
, Op_Id
, LT
);
1973 elsif Is_Array_Type
(RT
)
1974 and then LT
= Base_Type
(Component_Type
(RT
))
1976 Add_One_Interp
(N
, Op_Id
, RT
);
1978 -- If one operand is a string type or a user-defined array type,
1979 -- and the other is a literal, result is of the specific type.
1982 (Root_Type
(LT
) = Standard_String
1983 or else Scope
(LT
) /= Standard_Standard
)
1984 and then Etype
(R
) = Any_String
1986 Add_One_Interp
(N
, Op_Id
, LT
);
1989 (Root_Type
(RT
) = Standard_String
1990 or else Scope
(RT
) /= Standard_Standard
)
1991 and then Etype
(L
) = Any_String
1993 Add_One_Interp
(N
, Op_Id
, RT
);
1995 elsif not Is_Generic_Type
(Etype
(Op_Id
)) then
1996 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
1999 -- Type and its operations must be visible
2001 Set_Entity
(N
, Empty
);
2002 Analyze_Concatenation
(N
);
2006 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
2010 Op_Id
:= Get_Name_Entity_Id
(Name_Op_Concat
);
2011 while Present
(Op_Id
) loop
2012 if Ekind
(Op_Id
) = E_Operator
then
2014 -- Do not consider operators declared in dead code, they
2015 -- cannot be part of the resolution.
2017 if Is_Eliminated
(Op_Id
) then
2020 Find_Concatenation_Types
(L
, R
, Op_Id
, N
);
2024 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
2027 Op_Id
:= Homonym
(Op_Id
);
2032 end Analyze_Concatenation_Rest
;
2034 ------------------------------------
2035 -- Analyze_Comparison_Equality_Op --
2036 ------------------------------------
2038 procedure Analyze_Comparison_Equality_Op
(N
: Node_Id
) is
2039 Loc
: constant Source_Ptr
:= Sloc
(N
);
2040 L
: constant Node_Id
:= Left_Opnd
(N
);
2041 R
: constant Node_Id
:= Right_Opnd
(N
);
2046 Set_Etype
(N
, Any_Type
);
2047 Candidate_Type
:= Empty
;
2049 Analyze_Expression
(L
);
2050 Analyze_Expression
(R
);
2052 -- If the entity is set, the node is a generic instance with a non-local
2053 -- reference to the predefined operator or to a user-defined function.
2054 -- It can also be an inequality that is expanded into the negation of a
2055 -- call to a user-defined equality operator.
2057 -- For the predefined case, the result is Boolean, regardless of the
2058 -- type of the operands. The operands may even be limited, if they are
2059 -- generic actuals. If they are overloaded, label the operands with the
2060 -- common type that must be present, or with the type of the formal of
2061 -- the user-defined function.
2063 if Present
(Entity
(N
)) then
2064 Op_Id
:= Entity
(N
);
2066 if Ekind
(Op_Id
) = E_Operator
then
2067 Add_One_Interp
(N
, Op_Id
, Standard_Boolean
);
2069 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
2072 if Is_Overloaded
(L
) then
2073 if Ekind
(Op_Id
) = E_Operator
then
2074 Set_Etype
(L
, Intersect_Types
(L
, R
));
2076 Set_Etype
(L
, Etype
(First_Formal
(Op_Id
)));
2080 if Is_Overloaded
(R
) then
2081 if Ekind
(Op_Id
) = E_Operator
then
2082 Set_Etype
(R
, 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 No
(First_Formal
(Base_Type
(Designated_Type
(T
)))) then
2306 Get_Next_Interp
(I
, It
);
2313 elsif not Is_Function_Type
2314 and then Is_Overloaded
(N
)
2316 -- The prefix may include access to subprograms and other access
2317 -- types. If the context selects the interpretation that is a
2318 -- function call (not a procedure call) we cannot rewrite the node
2319 -- yet, but we include the result of the call interpretation.
2321 Get_First_Interp
(N
, I
, It
);
2322 while Present
(It
.Nam
) loop
2323 if Ekind
(Base_Type
(It
.Typ
)) = E_Subprogram_Type
2324 and then Etype
(Base_Type
(It
.Typ
)) /= Standard_Void_Type
2325 and then Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
2327 Add_One_Interp
(N
, Etype
(It
.Typ
), Etype
(It
.Typ
));
2330 Get_Next_Interp
(I
, It
);
2334 -- A value of remote access-to-class-wide must not be dereferenced
2337 Validate_Remote_Access_To_Class_Wide_Type
(N
);
2338 end Analyze_Explicit_Dereference
;
2340 ------------------------
2341 -- Analyze_Expression --
2342 ------------------------
2344 procedure Analyze_Expression
(N
: Node_Id
) is
2346 -- If the expression is an indexed component that will be rewritten
2347 -- as a container indexing, it has already been analyzed.
2349 if Nkind
(N
) = N_Indexed_Component
2350 and then Present
(Generalized_Indexing
(N
))
2356 Check_Parameterless_Call
(N
);
2358 end Analyze_Expression
;
2360 -------------------------------------
2361 -- Analyze_Expression_With_Actions --
2362 -------------------------------------
2364 procedure Analyze_Expression_With_Actions
(N
: Node_Id
) is
2366 procedure Check_Action_OK
(A
: Node_Id
);
2367 -- Check that the action A is allowed as a declare_item of a declare
2368 -- expression if N and A come from source.
2370 ---------------------
2371 -- Check_Action_OK --
2372 ---------------------
2374 procedure Check_Action_OK
(A
: Node_Id
) is
2376 if not Comes_From_Source
(N
) or else not Comes_From_Source
(A
) then
2378 -- If, for example, an (illegal) expression function is
2379 -- transformed into a "vanilla" function then we don't want to
2380 -- allow it just because Comes_From_Source is now False. So look
2381 -- at the Original_Node.
2383 if Is_Rewrite_Substitution
(A
) then
2384 Check_Action_OK
(Original_Node
(A
));
2387 return; -- Allow anything in generated code
2391 when N_Object_Declaration
=>
2392 if Nkind
(Object_Definition
(A
)) = N_Access_Definition
then
2394 ("anonymous access type not allowed in declare_expression",
2395 Object_Definition
(A
));
2398 if Aliased_Present
(A
) then
2399 Error_Msg_N
("ALIASED not allowed in declare_expression", A
);
2402 if Constant_Present
(A
)
2403 and then not Is_Limited_Type
(Etype
(Defining_Identifier
(A
)))
2405 return; -- nonlimited constants are OK
2408 when N_Object_Renaming_Declaration
=>
2409 if Present
(Access_Definition
(A
)) then
2411 ("anonymous access type not allowed in declare_expression",
2412 Access_Definition
(A
));
2415 if not Is_Limited_Type
(Etype
(Defining_Identifier
(A
))) then
2416 return; -- ???For now; the RM rule is a bit more complicated
2421 -- See AI22-0045 pragma categorization.
2422 subtype Executable_Pragma_Id
is Pragma_Id
2423 with Predicate
=> Executable_Pragma_Id
in
2424 -- language-defined executable pragmas
2425 Pragma_Assert | Pragma_Inspection_Point
2427 -- GNAT-defined executable pragmas
2428 | Pragma_Assume | Pragma_Debug
;
2430 if Get_Pragma_Id
(A
) in Executable_Pragma_Id
then
2436 null; -- Nothing else allowed
2439 -- We could mention pragmas in the message text; let's not.
2440 Error_Msg_N
("object renaming or constant declaration expected", A
);
2441 end Check_Action_OK
;
2444 EWA_Scop
: Entity_Id
;
2446 -- Start of processing for Analyze_Expression_With_Actions
2449 -- Create a scope, which is needed to provide proper visibility of the
2452 EWA_Scop
:= New_Internal_Entity
(E_Block
, Current_Scope
, Sloc
(N
), 'B');
2453 Set_Etype
(EWA_Scop
, Standard_Void_Type
);
2454 Set_Scope
(EWA_Scop
, Current_Scope
);
2455 Set_Parent
(EWA_Scop
, N
);
2456 Push_Scope
(EWA_Scop
);
2458 -- If this Expression_With_Actions node comes from source, then it
2459 -- represents a declare_expression; increment the counter to take note
2462 if Comes_From_Source
(N
) then
2463 In_Declare_Expr
:= In_Declare_Expr
+ 1;
2466 A
:= First
(Actions
(N
));
2467 while Present
(A
) loop
2469 Check_Action_OK
(A
);
2473 Analyze_Expression
(Expression
(N
));
2474 Set_Etype
(N
, Etype
(Expression
(N
)));
2477 if Comes_From_Source
(N
) then
2478 In_Declare_Expr
:= In_Declare_Expr
- 1;
2480 end Analyze_Expression_With_Actions
;
2482 ---------------------------
2483 -- Analyze_If_Expression --
2484 ---------------------------
2486 procedure Analyze_If_Expression
(N
: Node_Id
) is
2487 Condition
: constant Node_Id
:= First
(Expressions
(N
));
2489 Then_Expr
: Node_Id
;
2490 Else_Expr
: Node_Id
;
2492 procedure Check_Else_Expression
(T
: Entity_Id
);
2493 -- Check one interpretation of the THEN expression with type T
2495 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
);
2496 -- Check THEN expression with type T1 and ELSE expression with type T2
2498 ---------------------------
2499 -- Check_Else_Expression --
2500 ---------------------------
2502 procedure Check_Else_Expression
(T
: Entity_Id
) is
2507 -- Loop through the interpretations of the ELSE expression
2509 if not Is_Overloaded
(Else_Expr
) then
2510 Check_Expression_Pair
(T
, Etype
(Else_Expr
));
2513 Get_First_Interp
(Else_Expr
, I
, It
);
2514 while Present
(It
.Typ
) loop
2515 Check_Expression_Pair
(T
, It
.Typ
);
2516 Get_Next_Interp
(I
, It
);
2519 end Check_Else_Expression
;
2521 ---------------------------
2522 -- Check_Expression_Pair --
2523 ---------------------------
2525 procedure Check_Expression_Pair
(T1
, T2
: Entity_Id
) is
2529 if Covers
(T1
=> T1
, T2
=> T2
)
2530 or else Covers
(T1
=> T2
, T2
=> T1
)
2532 T
:= Specific_Type
(T1
, T2
);
2534 elsif Is_User_Defined_Literal
(Then_Expr
, T2
) then
2537 elsif Is_User_Defined_Literal
(Else_Expr
, T1
) then
2541 T
:= Possible_Type_For_Conditional_Expression
(T1
, T2
);
2548 Add_One_Interp
(N
, T
, T
);
2549 end Check_Expression_Pair
;
2556 -- Start of processing for Analyze_If_Expression
2559 -- Defend against error of missing expressions from previous error
2561 if No
(Condition
) then
2562 Check_Error_Detected
;
2566 Set_Etype
(N
, Any_Type
);
2568 Then_Expr
:= Next
(Condition
);
2570 if No
(Then_Expr
) then
2571 Check_Error_Detected
;
2575 Else_Expr
:= Next
(Then_Expr
);
2577 -- Analyze and resolve the condition. We need to resolve this now so
2578 -- that it gets folded to True/False if possible, before we analyze
2579 -- the THEN/ELSE branches, because when analyzing these branches, we
2580 -- may call Is_Statically_Unevaluated, which expects the condition of
2581 -- an enclosing IF to have been analyze/resolved/evaluated.
2583 Analyze_Expression
(Condition
);
2584 Resolve
(Condition
, Any_Boolean
);
2586 -- Analyze the THEN expression and (if present) the ELSE expression. For
2587 -- them we delay resolution in the normal manner because of overloading.
2589 Analyze_Expression
(Then_Expr
);
2591 if Present
(Else_Expr
) then
2592 Analyze_Expression
(Else_Expr
);
2595 -- RM 4.5.7(10/3): If the if_expression is the operand of a type
2596 -- conversion, the type of the if_expression is the target type
2597 -- of the conversion.
2599 if Nkind
(Parent
(N
)) = N_Type_Conversion
then
2600 Set_Etype
(N
, Etype
(Parent
(N
)));
2604 -- Loop through the interpretations of the THEN expression and check the
2605 -- ELSE expression if present.
2607 if not Is_Overloaded
(Then_Expr
) then
2608 if Present
(Else_Expr
) then
2609 Check_Else_Expression
(Etype
(Then_Expr
));
2611 Set_Etype
(N
, Etype
(Then_Expr
));
2615 Get_First_Interp
(Then_Expr
, I
, It
);
2616 while Present
(It
.Typ
) loop
2617 if Present
(Else_Expr
) then
2618 Check_Else_Expression
(It
.Typ
);
2620 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
2623 Get_Next_Interp
(I
, It
);
2627 -- If no possible interpretation has been found, the type of the
2628 -- ELSE expression does not match any interpretation of the THEN
2631 if Etype
(N
) = Any_Type
then
2632 if Is_Overloaded
(Then_Expr
) then
2633 if Is_Overloaded
(Else_Expr
) then
2635 ("no interpretation compatible with those of THEN expression",
2639 ("type of ELSE incompatible with interpretations of THEN "
2643 ("\ELSE expression has}!", Else_Expr
, Etype
(Else_Expr
));
2647 if Is_Overloaded
(Else_Expr
) then
2649 ("no interpretation compatible with type of THEN expression",
2652 ("\THEN expression has}!", Else_Expr
, Etype
(Then_Expr
));
2655 ("type of ELSE incompatible with that of THEN expression",
2658 ("\THEN expression has}!", Else_Expr
, Etype
(Then_Expr
));
2660 ("\ELSE expression has}!", Else_Expr
, Etype
(Else_Expr
));
2664 end Analyze_If_Expression
;
2666 ------------------------------------
2667 -- Analyze_Indexed_Component_Form --
2668 ------------------------------------
2670 procedure Analyze_Indexed_Component_Form
(N
: Node_Id
) is
2671 P
: constant Node_Id
:= Prefix
(N
);
2672 Exprs
: constant List_Id
:= Expressions
(N
);
2678 procedure Process_Function_Call
;
2679 -- Prefix in indexed component form is an overloadable entity, so the
2680 -- node is very likely a function call; reformat it as such. The only
2681 -- exception is a call to a parameterless function that returns an
2682 -- array type, or an access type thereof, in which case this will be
2683 -- undone later by Resolve_Call or Resolve_Entry_Call.
2685 procedure Process_Indexed_Component
;
2686 -- Prefix in indexed component form is actually an indexed component.
2687 -- This routine processes it, knowing that the prefix is already
2690 procedure Process_Indexed_Component_Or_Slice
;
2691 -- An indexed component with a single index may designate a slice if
2692 -- the index is a subtype mark. This routine disambiguates these two
2693 -- cases by resolving the prefix to see if it is a subtype mark.
2695 procedure Process_Overloaded_Indexed_Component
;
2696 -- If the prefix of an indexed component is overloaded, the proper
2697 -- interpretation is selected by the index types and the context.
2699 ---------------------------
2700 -- Process_Function_Call --
2701 ---------------------------
2703 procedure Process_Function_Call
is
2704 Loc
: constant Source_Ptr
:= Sloc
(N
);
2708 Change_Node
(N
, N_Function_Call
);
2710 Set_Parameter_Associations
(N
, Exprs
);
2712 -- Analyze actuals prior to analyzing the call itself
2714 Actual
:= First
(Parameter_Associations
(N
));
2715 while Present
(Actual
) loop
2717 Check_Parameterless_Call
(Actual
);
2719 -- Move to next actual. Note that we use Next, not Next_Actual
2720 -- here. The reason for this is a bit subtle. If a function call
2721 -- includes named associations, the parser recognizes the node
2722 -- as a call, and it is analyzed as such. If all associations are
2723 -- positional, the parser builds an indexed_component node, and
2724 -- it is only after analysis of the prefix that the construct
2725 -- is recognized as a call, in which case Process_Function_Call
2726 -- rewrites the node and analyzes the actuals. If the list of
2727 -- actuals is malformed, the parser may leave the node as an
2728 -- indexed component (despite the presence of named associations).
2729 -- The iterator Next_Actual is equivalent to Next if the list is
2730 -- positional, but follows the normalized chain of actuals when
2731 -- named associations are present. In this case normalization has
2732 -- not taken place, and actuals remain unanalyzed, which leads to
2733 -- subsequent crashes or loops if there is an attempt to continue
2734 -- analysis of the program.
2736 -- IF there is a single actual and it is a type name, the node
2737 -- can only be interpreted as a slice of a parameterless call.
2738 -- Rebuild the node as such and analyze.
2740 if No
(Next
(Actual
))
2741 and then Is_Entity_Name
(Actual
)
2742 and then Is_Type
(Entity
(Actual
))
2743 and then Is_Discrete_Type
(Entity
(Actual
))
2744 and then not Is_Current_Instance
(Actual
)
2750 New_Occurrence_Of
(Entity
(Actual
), Loc
)));
2760 end Process_Function_Call
;
2762 -------------------------------
2763 -- Process_Indexed_Component --
2764 -------------------------------
2766 procedure Process_Indexed_Component
is
2768 Array_Type
: Entity_Id
;
2770 Pent
: Entity_Id
:= Empty
;
2773 Exp
:= First
(Exprs
);
2775 if Is_Overloaded
(P
) then
2776 Process_Overloaded_Indexed_Component
;
2779 Array_Type
:= Etype
(P
);
2781 if Is_Entity_Name
(P
) then
2783 elsif Nkind
(P
) = N_Selected_Component
2784 and then Is_Entity_Name
(Selector_Name
(P
))
2786 Pent
:= Entity
(Selector_Name
(P
));
2789 -- Prefix must be appropriate for an array type, taking into
2790 -- account a possible implicit dereference.
2792 if Is_Access_Type
(Array_Type
) then
2794 (Warn_On_Dereference
, "?d?implicit dereference", N
);
2795 Array_Type
:= Implicitly_Designated_Type
(Array_Type
);
2798 if Is_Array_Type
(Array_Type
) then
2800 -- In order to correctly access First_Index component later,
2801 -- replace string literal subtype by its parent type.
2803 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
2804 Array_Type
:= Etype
(Array_Type
);
2807 elsif Present
(Pent
) and then Ekind
(Pent
) = E_Entry_Family
then
2809 Set_Etype
(N
, Any_Type
);
2811 if not Has_Compatible_Type
(Exp
, Entry_Index_Type
(Pent
)) then
2812 Error_Msg_N
("invalid index type in entry name", N
);
2814 elsif Present
(Next
(Exp
)) then
2815 Error_Msg_N
("too many subscripts in entry reference", N
);
2818 Set_Etype
(N
, Etype
(P
));
2823 elsif Is_Record_Type
(Array_Type
)
2824 and then Remote_AST_I_Dereference
(P
)
2828 elsif Try_Container_Indexing
(N
, P
, Exprs
) then
2831 elsif Array_Type
= Any_Type
then
2832 Set_Etype
(N
, Any_Type
);
2834 -- In most cases the analysis of the prefix will have emitted
2835 -- an error already, but if the prefix may be interpreted as a
2836 -- call in prefixed notation, the report is left to the caller.
2837 -- To prevent cascaded errors, report only if no previous ones.
2839 if Serious_Errors_Detected
= 0 then
2840 Error_Msg_N
("invalid prefix in indexed component", P
);
2842 if Nkind
(P
) = N_Expanded_Name
then
2843 Error_Msg_NE
("\& is not visible", P
, Selector_Name
(P
));
2849 -- Here we definitely have a bad indexing
2852 if Nkind
(Parent
(N
)) = N_Requeue_Statement
2853 and then Present
(Pent
) and then Ekind
(Pent
) = E_Entry
2856 ("REQUEUE does not permit parameters", First
(Exprs
));
2858 elsif Is_Entity_Name
(P
)
2859 and then Etype
(P
) = Standard_Void_Type
2861 Error_Msg_NE
("incorrect use of &", P
, Entity
(P
));
2864 Error_Msg_N
("array type required in indexed component", P
);
2867 Set_Etype
(N
, Any_Type
);
2871 Index
:= First_Index
(Array_Type
);
2872 while Present
(Index
) and then Present
(Exp
) loop
2873 if not Has_Compatible_Type
(Exp
, Etype
(Index
)) then
2874 Wrong_Type
(Exp
, Etype
(Index
));
2875 Set_Etype
(N
, Any_Type
);
2883 Set_Etype
(N
, Component_Type
(Array_Type
));
2884 Check_Implicit_Dereference
(N
, Etype
(N
));
2886 if Present
(Index
) then
2888 ("too few subscripts in array reference", First
(Exprs
));
2890 elsif Present
(Exp
) then
2891 Error_Msg_N
("too many subscripts in array reference", Exp
);
2894 end Process_Indexed_Component
;
2896 ----------------------------------------
2897 -- Process_Indexed_Component_Or_Slice --
2898 ----------------------------------------
2900 procedure Process_Indexed_Component_Or_Slice
is
2902 Exp
:= First
(Exprs
);
2903 while Present
(Exp
) loop
2904 Analyze_Expression
(Exp
);
2908 Exp
:= First
(Exprs
);
2910 -- If one index is present, and it is a subtype name, then the node
2911 -- denotes a slice (note that the case of an explicit range for a
2912 -- slice was already built as an N_Slice node in the first place,
2913 -- so that case is not handled here).
2915 -- We use a replace rather than a rewrite here because this is one
2916 -- of the cases in which the tree built by the parser is plain wrong.
2919 and then Is_Entity_Name
(Exp
)
2920 and then Is_Type
(Entity
(Exp
))
2923 Make_Slice
(Sloc
(N
),
2925 Discrete_Range
=> New_Copy
(Exp
)));
2928 -- Otherwise (more than one index present, or single index is not
2929 -- a subtype name), then we have the indexed component case.
2932 Process_Indexed_Component
;
2934 end Process_Indexed_Component_Or_Slice
;
2936 ------------------------------------------
2937 -- Process_Overloaded_Indexed_Component --
2938 ------------------------------------------
2940 procedure Process_Overloaded_Indexed_Component
is
2949 Set_Etype
(N
, Any_Type
);
2951 Get_First_Interp
(P
, I
, It
);
2952 while Present
(It
.Nam
) loop
2955 if Is_Access_Type
(Typ
) then
2956 Typ
:= Designated_Type
(Typ
);
2958 (Warn_On_Dereference
, "?d?implicit dereference", N
);
2961 if Is_Array_Type
(Typ
) then
2963 -- Got a candidate: verify that index types are compatible
2965 Index
:= First_Index
(Typ
);
2967 Exp
:= First
(Exprs
);
2968 while Present
(Index
) and then Present
(Exp
) loop
2969 if Has_Compatible_Type
(Exp
, Etype
(Index
)) then
2981 if Found
and then No
(Index
) and then No
(Exp
) then
2983 CT
: constant Entity_Id
:=
2984 Base_Type
(Component_Type
(Typ
));
2986 Add_One_Interp
(N
, CT
, CT
);
2987 Check_Implicit_Dereference
(N
, CT
);
2991 elsif Try_Container_Indexing
(N
, P
, Exprs
) then
2996 Get_Next_Interp
(I
, It
);
2999 if Etype
(N
) = Any_Type
then
3000 Error_Msg_N
("no legal interpretation for indexed component", N
);
3001 Set_Is_Overloaded
(N
, False);
3003 end Process_Overloaded_Indexed_Component
;
3005 -- Start of processing for Analyze_Indexed_Component_Form
3008 -- Get name of array, function or type
3012 -- If P is an explicit dereference whose prefix is of a remote access-
3013 -- to-subprogram type, then N has already been rewritten as a subprogram
3014 -- call and analyzed.
3016 if Nkind
(N
) in N_Subprogram_Call
then
3019 -- When the prefix is attribute 'Loop_Entry and the sole expression of
3020 -- the indexed component denotes a loop name, the indexed form is turned
3021 -- into an attribute reference.
3023 elsif Nkind
(N
) = N_Attribute_Reference
3024 and then Attribute_Name
(N
) = Name_Loop_Entry
3029 pragma Assert
(Nkind
(N
) = N_Indexed_Component
);
3031 P_T
:= Base_Type
(Etype
(P
));
3033 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
3036 if Is_Type
(U_N
) then
3038 -- Reformat node as a type conversion
3040 E
:= Remove_Head
(Exprs
);
3042 if Present
(First
(Exprs
)) then
3044 ("argument of type conversion must be single expression", N
);
3047 Change_Node
(N
, N_Type_Conversion
);
3048 Set_Subtype_Mark
(N
, P
);
3050 Set_Expression
(N
, E
);
3052 -- After changing the node, call for the specific Analysis
3053 -- routine directly, to avoid a double call to the expander.
3055 Analyze_Type_Conversion
(N
);
3059 if Is_Overloadable
(U_N
) then
3060 Process_Function_Call
;
3062 elsif Ekind
(Etype
(P
)) = E_Subprogram_Type
3063 or else (Is_Access_Type
(Etype
(P
))
3065 Ekind
(Designated_Type
(Etype
(P
))) =
3068 -- Call to access_to-subprogram with possible implicit dereference
3070 Process_Function_Call
;
3072 elsif Is_Generic_Subprogram
(U_N
) then
3074 -- A common beginner's (or C++ templates fan) error
3076 Error_Msg_N
("generic subprogram cannot be called", N
);
3077 Set_Etype
(N
, Any_Type
);
3081 Process_Indexed_Component_Or_Slice
;
3084 -- If not an entity name, prefix is an expression that may denote
3085 -- an array or an access-to-subprogram.
3088 if Ekind
(P_T
) = E_Subprogram_Type
3089 or else (Is_Access_Type
(P_T
)
3091 Ekind
(Designated_Type
(P_T
)) = E_Subprogram_Type
)
3093 Process_Function_Call
;
3095 elsif Nkind
(P
) = N_Selected_Component
3096 and then Present
(Entity
(Selector_Name
(P
)))
3097 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
3099 Process_Function_Call
;
3101 -- Indexed component, slice, or a call to a member of a family
3102 -- entry, which will be converted to an entry call later.
3104 Process_Indexed_Component_Or_Slice
;
3108 Analyze_Dimension
(N
);
3109 end Analyze_Indexed_Component_Form
;
3111 ------------------------
3112 -- Analyze_Logical_Op --
3113 ------------------------
3115 procedure Analyze_Logical_Op
(N
: Node_Id
) is
3116 L
: constant Node_Id
:= Left_Opnd
(N
);
3117 R
: constant Node_Id
:= Right_Opnd
(N
);
3122 Set_Etype
(N
, Any_Type
);
3123 Candidate_Type
:= Empty
;
3125 Analyze_Expression
(L
);
3126 Analyze_Expression
(R
);
3128 -- If the entity is already set, the node is the instantiation of a
3129 -- generic node with a non-local reference, or was manufactured by a
3130 -- call to Make_Op_xxx. In either case the entity is known to be valid,
3131 -- and we do not need to collect interpretations, instead we just get
3132 -- the single possible interpretation.
3134 if Present
(Entity
(N
)) then
3135 Op_Id
:= Entity
(N
);
3137 if Ekind
(Op_Id
) = E_Operator
then
3138 Find_Boolean_Types
(L
, R
, Op_Id
, N
);
3140 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
3143 -- Entity is not already set, so we do need to collect interpretations
3146 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
3147 while Present
(Op_Id
) loop
3148 if Ekind
(Op_Id
) = E_Operator
then
3149 Find_Boolean_Types
(L
, R
, Op_Id
, N
);
3151 Analyze_User_Defined_Binary_Op
(N
, Op_Id
);
3154 Op_Id
:= Homonym
(Op_Id
);
3159 Check_Function_Writable_Actuals
(N
);
3162 if Nkind
(L
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
3163 and then Is_Boolean_Type
(Etype
(L
))
3165 Check_Xtra_Parens_Precedence
(L
);
3168 if Nkind
(R
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
3169 and then Is_Boolean_Type
(Etype
(R
))
3171 Check_Xtra_Parens_Precedence
(R
);
3174 end Analyze_Logical_Op
;
3176 ---------------------------
3177 -- Analyze_Membership_Op --
3178 ---------------------------
3180 procedure Analyze_Membership_Op
(N
: Node_Id
) is
3181 Loc
: constant Source_Ptr
:= Sloc
(N
);
3182 L
: constant Node_Id
:= Left_Opnd
(N
);
3183 R
: constant Node_Id
:= Right_Opnd
(N
);
3185 procedure Analyze_Set_Membership
;
3186 -- If a set of alternatives is present, analyze each and find the
3187 -- common type to which they must all resolve.
3189 function Find_Interp
return Boolean;
3190 -- Find a valid interpretation of the test. Note that the context of the
3191 -- operation plays no role in resolving the operands, so that if there
3192 -- is more than one interpretation of the operands that is compatible
3193 -- with the test, the operation is ambiguous.
3195 function Try_Left_Interp
(T
: Entity_Id
) return Boolean;
3196 -- Try an interpretation of the left operand with type T. Return true if
3197 -- one interpretation (at least) of the right operand making up a valid
3198 -- operand pair exists, otherwise false if no such pair exists.
3200 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean;
3201 -- Return true if T1 and T2 constitute a valid pair of operand types for
3202 -- L and R respectively.
3204 ----------------------------
3205 -- Analyze_Set_Membership --
3206 ----------------------------
3208 procedure Analyze_Set_Membership
is
3210 Index
: Interp_Index
;
3212 Candidate_Interps
: Node_Id
;
3213 Common_Type
: Entity_Id
:= Empty
;
3217 Candidate_Interps
:= L
;
3219 if not Is_Overloaded
(L
) then
3220 Common_Type
:= Etype
(L
);
3222 Alt
:= First
(Alternatives
(N
));
3223 while Present
(Alt
) loop
3226 if not Has_Compatible_Type
(Alt
, Common_Type
) then
3227 Wrong_Type
(Alt
, Common_Type
);
3234 Alt
:= First
(Alternatives
(N
));
3235 while Present
(Alt
) loop
3237 if not Is_Overloaded
(Alt
) then
3238 Common_Type
:= Etype
(Alt
);
3241 Get_First_Interp
(Alt
, Index
, It
);
3242 while Present
(It
.Typ
) loop
3244 Has_Compatible_Type
(Candidate_Interps
, It
.Typ
)
3246 Remove_Interp
(Index
);
3249 Get_Next_Interp
(Index
, It
);
3252 Get_First_Interp
(Alt
, Index
, It
);
3255 Error_Msg_N
("alternative has no legal type", Alt
);
3259 -- If alternative is not overloaded, we have a unique type
3262 Set_Etype
(Alt
, It
.Typ
);
3264 -- If the alternative is an enumeration literal, use the one
3265 -- for this interpretation.
3267 if Is_Entity_Name
(Alt
) then
3268 Set_Entity
(Alt
, It
.Nam
);
3271 Get_Next_Interp
(Index
, It
);
3274 Set_Is_Overloaded
(Alt
, False);
3275 Common_Type
:= Etype
(Alt
);
3278 Candidate_Interps
:= Alt
;
3285 if Present
(Common_Type
) then
3286 Set_Etype
(L
, Common_Type
);
3288 -- The left operand may still be overloaded, to be resolved using
3292 Error_Msg_N
("cannot resolve membership operation", N
);
3294 end Analyze_Set_Membership
;
3300 function Find_Interp
return Boolean is
3305 Valid_I
: Interp_Index
;
3308 -- Loop through the interpretations of the left operand
3310 if not Is_Overloaded
(L
) then
3311 Found
:= Try_Left_Interp
(Etype
(L
));
3318 Get_First_Interp
(L
, I
, It
);
3319 while Present
(It
.Typ
) loop
3320 if Try_Left_Interp
(It
.Typ
) then
3321 -- If several interpretations are possible, disambiguate
3324 and then Base_Type
(It
.Typ
) /= Base_Type
(L_Typ
)
3326 It
:= Disambiguate
(L
, Valid_I
, I
, Any_Type
);
3328 if It
= No_Interp
then
3329 Ambiguous_Operands
(N
);
3330 Set_Etype
(L
, Any_Type
);
3339 Set_Etype
(L
, L_Typ
);
3343 Get_Next_Interp
(I
, It
);
3350 ---------------------
3351 -- Try_Left_Interp --
3352 ---------------------
3354 function Try_Left_Interp
(T
: Entity_Id
) return Boolean is
3359 Valid_I
: Interp_Index
;
3362 -- Defend against previous error
3364 if Nkind
(R
) = N_Error
then
3367 -- Loop through the interpretations of the right operand
3369 elsif not Is_Overloaded
(R
) then
3370 Found
:= Is_Valid_Pair
(T
, Etype
(R
));
3377 Get_First_Interp
(R
, I
, It
);
3378 while Present
(It
.Typ
) loop
3379 if Is_Valid_Pair
(T
, It
.Typ
) then
3380 -- If several interpretations are possible, disambiguate
3383 and then Base_Type
(It
.Typ
) /= Base_Type
(R_Typ
)
3385 It
:= Disambiguate
(R
, Valid_I
, I
, Any_Type
);
3387 if It
= No_Interp
then
3388 Ambiguous_Operands
(N
);
3389 Set_Etype
(R
, Any_Type
);
3401 Get_Next_Interp
(I
, It
);
3406 end Try_Left_Interp
;
3412 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean is
3414 return Covers
(T1
=> T1
, T2
=> T2
)
3415 or else Covers
(T1
=> T2
, T2
=> T1
)
3416 or else Is_User_Defined_Literal
(L
, T2
)
3417 or else Is_User_Defined_Literal
(R
, T1
);
3425 -- Start of processing for Analyze_Membership_Op
3428 Analyze_Expression
(L
);
3431 pragma Assert
(Ada_Version
>= Ada_2012
);
3433 Analyze_Set_Membership
;
3438 Alt
:= First
(Alternatives
(N
));
3439 while Present
(Alt
) loop
3440 if Is_Entity_Name
(Alt
) and then Is_Type
(Entity
(Alt
)) then
3441 Check_Fully_Declared
(Entity
(Alt
), Alt
);
3443 if Has_Ghost_Predicate_Aspect
(Entity
(Alt
)) then
3445 ("subtype& has ghost predicate, "
3446 & "not allowed in membership test",
3455 elsif Nkind
(R
) = N_Range
3456 or else (Nkind
(R
) = N_Attribute_Reference
3457 and then Attribute_Name
(R
) = Name_Range
)
3459 Analyze_Expression
(R
);
3461 Dummy
:= Find_Interp
;
3463 -- If not a range, it can be a subtype mark, or else it is a degenerate
3464 -- membership test with a singleton value, i.e. a test for equality,
3465 -- if the types are compatible.
3468 Analyze_Expression
(R
);
3470 if Is_Entity_Name
(R
) and then Is_Type
(Entity
(R
)) then
3472 Check_Fully_Declared
(Entity
(R
), R
);
3474 if Has_Ghost_Predicate_Aspect
(Entity
(R
)) then
3476 ("subtype& has ghost predicate, "
3477 & "not allowed in membership test",
3481 elsif Ada_Version
>= Ada_2012
and then Find_Interp
then
3482 Op
:= Make_Op_Eq
(Loc
, Left_Opnd
=> L
, Right_Opnd
=> R
);
3483 Resolve_Membership_Equality
(Op
, Etype
(L
));
3485 if Nkind
(N
) = N_Not_In
then
3486 Op
:= Make_Op_Not
(Loc
, Op
);
3494 -- In all versions of the language, if we reach this point there
3495 -- is a previous error that will be diagnosed below.
3501 -- Compatibility between expression and subtype mark or range is
3502 -- checked during resolution. The result of the operation is Boolean
3505 Set_Etype
(N
, Standard_Boolean
);
3507 if Comes_From_Source
(N
)
3508 and then Present
(Right_Opnd
(N
))
3509 and then Is_CPP_Class
(Etype
(Etype
(Right_Opnd
(N
))))
3511 Error_Msg_N
("membership test not applicable to cpp-class types", N
);
3514 Check_Function_Writable_Actuals
(N
);
3515 end Analyze_Membership_Op
;
3521 procedure Analyze_Mod
(N
: Node_Id
) is
3523 -- A special warning check, if we have an expression of the form:
3524 -- expr mod 2 * literal
3525 -- where literal is 128 or less, then probably what was meant was
3526 -- expr mod 2 ** literal
3527 -- so issue an appropriate warning.
3529 if Warn_On_Suspicious_Modulus_Value
3530 and then Nkind
(Right_Opnd
(N
)) = N_Integer_Literal
3531 and then Intval
(Right_Opnd
(N
)) = Uint_2
3532 and then Nkind
(Parent
(N
)) = N_Op_Multiply
3533 and then Nkind
(Right_Opnd
(Parent
(N
))) = N_Integer_Literal
3534 and then Intval
(Right_Opnd
(Parent
(N
))) <= Uint_128
3537 ("suspicious MOD value, was '*'* intended'??.m?", Parent
(N
));
3540 -- Remaining processing is same as for other arithmetic operators
3542 Analyze_Arithmetic_Op
(N
);
3545 ----------------------
3546 -- Analyze_Negation --
3547 ----------------------
3549 procedure Analyze_Negation
(N
: Node_Id
) is
3550 R
: constant Node_Id
:= Right_Opnd
(N
);
3555 Set_Etype
(N
, Any_Type
);
3556 Candidate_Type
:= Empty
;
3558 Analyze_Expression
(R
);
3560 -- If the entity is already set, the node is the instantiation of a
3561 -- generic node with a non-local reference, or was manufactured by a
3562 -- call to Make_Op_xxx. In either case the entity is known to be valid,
3563 -- and we do not need to collect interpretations, instead we just get
3564 -- the single possible interpretation.
3566 if Present
(Entity
(N
)) then
3567 Op_Id
:= Entity
(N
);
3569 if Ekind
(Op_Id
) = E_Operator
then
3570 Find_Negation_Types
(R
, Op_Id
, N
);
3572 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
3576 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
3577 while Present
(Op_Id
) loop
3578 if Ekind
(Op_Id
) = E_Operator
then
3579 Find_Negation_Types
(R
, Op_Id
, N
);
3581 Analyze_User_Defined_Unary_Op
(N
, Op_Id
);
3584 Op_Id
:= Homonym
(Op_Id
);
3589 end Analyze_Negation
;
3595 procedure Analyze_Null
(N
: Node_Id
) is
3597 Set_Etype
(N
, Universal_Access
);
3600 ----------------------
3601 -- Analyze_One_Call --
3602 ----------------------
3604 procedure Analyze_One_Call
3608 Success
: out Boolean;
3609 Skip_First
: Boolean := False)
3611 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
3612 Prev_T
: constant Entity_Id
:= Etype
(N
);
3614 -- Recognize cases of prefixed calls that have been rewritten in
3615 -- various ways. The simplest case is a rewritten selected component,
3616 -- but it can also be an already-examined indexed component, or a
3617 -- prefix that is itself a rewritten prefixed call that is in turn
3618 -- an indexed call (the syntactic ambiguity involving the indexing of
3619 -- a function with defaulted parameters that returns an array).
3620 -- A flag Maybe_Indexed_Call might be useful here ???
3622 Must_Skip
: constant Boolean := Skip_First
3623 or else Nkind
(Original_Node
(N
)) = N_Selected_Component
3625 (Nkind
(Original_Node
(N
)) = N_Indexed_Component
3626 and then Nkind
(Prefix
(Original_Node
(N
))) =
3627 N_Selected_Component
)
3629 (Nkind
(Parent
(N
)) = N_Function_Call
3630 and then Is_Array_Type
(Etype
(Name
(N
)))
3631 and then Etype
(Original_Node
(N
)) =
3632 Component_Type
(Etype
(Name
(N
)))
3633 and then Nkind
(Original_Node
(Parent
(N
))) =
3634 N_Selected_Component
);
3636 -- The first formal must be omitted from the match when trying to find
3637 -- a primitive operation that is a possible interpretation, and also
3638 -- after the call has been rewritten, because the corresponding actual
3639 -- is already known to be compatible, and because this may be an
3640 -- indexing of a call with default parameters.
3642 First_Form
: Entity_Id
;
3645 Is_Indexed
: Boolean := False;
3646 Is_Indirect
: Boolean := False;
3647 Subp_Type
: constant Entity_Id
:= Etype
(Nam
);
3650 function Compatible_Types_In_Predicate
3652 T2
: Entity_Id
) return Boolean;
3653 -- For an Ada 2012 predicate or invariant, a call may mention an
3654 -- incomplete type, while resolution of the corresponding predicate
3655 -- function may see the full view, as a consequence of the delayed
3656 -- resolution of the corresponding expressions. This may occur in
3657 -- the body of a predicate function, or in a call to such. Anomalies
3658 -- involving private and full views can also happen. In each case,
3659 -- rewrite node or add conversions to remove spurious type errors.
3661 procedure Indicate_Name_And_Type
;
3662 -- If candidate interpretation matches, indicate name and type of result
3665 function Operator_Hidden_By
(Fun
: Entity_Id
) return Boolean;
3666 -- There may be a user-defined operator that hides the current
3667 -- interpretation. We must check for this independently of the
3668 -- analysis of the call with the user-defined operation, because
3669 -- the parameter names may be wrong and yet the hiding takes place.
3670 -- This fixes a problem with ACATS test B34014O.
3672 -- When the type Address is a visible integer type, and the DEC
3673 -- system extension is visible, the predefined operator may be
3674 -- hidden as well, by one of the address operations in auxdec.
3675 -- Finally, the abstract operations on address do not hide the
3676 -- predefined operator (this is the purpose of making them abstract).
3678 -----------------------------------
3679 -- Compatible_Types_In_Predicate --
3680 -----------------------------------
3682 function Compatible_Types_In_Predicate
3684 T2
: Entity_Id
) return Boolean
3686 function Common_Type
(T
: Entity_Id
) return Entity_Id
;
3687 -- Find non-private underlying full view if any, without going to
3688 -- ancestor type (as opposed to Underlying_Type).
3694 function Common_Type
(T
: Entity_Id
) return Entity_Id
is
3700 if Is_Private_Type
(CT
) and then Present
(Full_View
(CT
)) then
3701 CT
:= Full_View
(CT
);
3704 if Is_Private_Type
(CT
)
3705 and then Present
(Underlying_Full_View
(CT
))
3707 CT
:= Underlying_Full_View
(CT
);
3710 return Base_Type
(CT
);
3713 -- Start of processing for Compatible_Types_In_Predicate
3716 if (Ekind
(Current_Scope
) = E_Function
3717 and then Is_Predicate_Function
(Current_Scope
))
3719 (Ekind
(Nam
) = E_Function
3720 and then Is_Predicate_Function
(Nam
))
3722 if Is_Incomplete_Type
(T1
)
3723 and then Present
(Full_View
(T1
))
3724 and then Full_View
(T1
) = T2
3726 Set_Etype
(Formal
, Etype
(Actual
));
3729 elsif Common_Type
(T1
) = Common_Type
(T2
) then
3730 Rewrite
(Actual
, Unchecked_Convert_To
(Etype
(Formal
), Actual
));
3740 end Compatible_Types_In_Predicate
;
3742 ----------------------------
3743 -- Indicate_Name_And_Type --
3744 ----------------------------
3746 procedure Indicate_Name_And_Type
is
3748 Add_One_Interp
(N
, Nam
, Etype
(Nam
));
3749 Check_Implicit_Dereference
(N
, Etype
(Nam
));
3752 -- If the prefix of the call is a name, indicate the entity
3753 -- being called. If it is not a name, it is an expression that
3754 -- denotes an access to subprogram or else an entry or family. In
3755 -- the latter case, the name is a selected component, and the entity
3756 -- being called is noted on the selector.
3758 if not Is_Type
(Nam
) then
3759 if Is_Entity_Name
(Name
(N
)) then
3760 Set_Entity
(Name
(N
), Nam
);
3761 Set_Etype
(Name
(N
), Etype
(Nam
));
3763 elsif Nkind
(Name
(N
)) = N_Selected_Component
then
3764 Set_Entity
(Selector_Name
(Name
(N
)), Nam
);
3768 if Debug_Flag_E
and not Report
then
3769 Write_Str
(" Overloaded call ");
3770 Write_Int
(Int
(N
));
3771 Write_Str
(" compatible with ");
3772 Write_Int
(Int
(Nam
));
3775 end Indicate_Name_And_Type
;
3777 ------------------------
3778 -- Operator_Hidden_By --
3779 ------------------------
3781 function Operator_Hidden_By
(Fun
: Entity_Id
) return Boolean is
3782 Act1
: constant Node_Id
:= First_Actual
(N
);
3783 Act2
: constant Node_Id
:= Next_Actual
(Act1
);
3784 Form1
: constant Entity_Id
:= First_Formal
(Fun
);
3785 Form2
: constant Entity_Id
:= Next_Formal
(Form1
);
3788 if Ekind
(Fun
) /= E_Function
or else Is_Abstract_Subprogram
(Fun
) then
3791 elsif not Has_Compatible_Type
(Act1
, Etype
(Form1
)) then
3794 elsif Present
(Form2
) then
3796 or else not Has_Compatible_Type
(Act2
, Etype
(Form2
))
3801 elsif Present
(Act2
) then
3805 -- Now we know that the arity of the operator matches the function,
3806 -- and the function call is a valid interpretation. The function
3807 -- hides the operator if it has the right signature, or if one of
3808 -- its operands is a non-abstract operation on Address when this is
3809 -- a visible integer type.
3811 return Hides_Op
(Fun
, Nam
)
3812 or else Is_Descendant_Of_Address
(Etype
(Form1
))
3815 and then Is_Descendant_Of_Address
(Etype
(Form2
)));
3816 end Operator_Hidden_By
;
3818 -- Start of processing for Analyze_One_Call
3823 -- If the subprogram has no formals or if all the formals have defaults,
3824 -- and the return type is an array type, the node may denote an indexing
3825 -- of the result of a parameterless call. In Ada 2005, the subprogram
3826 -- may have one non-defaulted formal, and the call may have been written
3827 -- in prefix notation, so that the rebuilt parameter list has more than
3830 if not Is_Overloadable
(Nam
)
3831 and then Ekind
(Nam
) /= E_Subprogram_Type
3832 and then Ekind
(Nam
) /= E_Entry_Family
3837 -- An indexing requires at least one actual. The name of the call cannot
3838 -- be an implicit indirect call, so it cannot be a generated explicit
3841 if not Is_Empty_List
(Actuals
)
3843 (Needs_No_Actuals
(Nam
)
3845 (Needs_One_Actual
(Nam
)
3846 and then Present
(Next_Actual
(First
(Actuals
)))))
3848 if Is_Array_Type
(Subp_Type
)
3850 (Nkind
(Name
(N
)) /= N_Explicit_Dereference
3851 or else Comes_From_Source
(Name
(N
)))
3853 Is_Indexed
:= Try_Indexed_Call
(N
, Nam
, Subp_Type
, Must_Skip
);
3855 elsif Is_Access_Type
(Subp_Type
)
3856 and then Is_Array_Type
(Designated_Type
(Subp_Type
))
3860 (N
, Nam
, Designated_Type
(Subp_Type
), Must_Skip
);
3862 -- The prefix can also be a parameterless function that returns an
3863 -- access to subprogram, in which case this is an indirect call.
3864 -- If this succeeds, an explicit dereference is added later on,
3865 -- in Analyze_Call or Resolve_Call.
3867 elsif Is_Access_Type
(Subp_Type
)
3868 and then Ekind
(Designated_Type
(Subp_Type
)) = E_Subprogram_Type
3870 Is_Indirect
:= Try_Indirect_Call
(N
, Nam
, Subp_Type
);
3875 -- If the call has been transformed into a slice, it is of the form
3876 -- F (Subtype) where F is parameterless. The node has been rewritten in
3877 -- Try_Indexed_Call and there is nothing else to do.
3880 and then Nkind
(N
) = N_Slice
3886 (N
, Nam
, (Report
and not Is_Indexed
and not Is_Indirect
), Norm_OK
);
3890 -- If an indirect call is a possible interpretation, indicate
3891 -- success to the caller. This may be an indexing of an explicit
3892 -- dereference of a call that returns an access type (see above).
3896 and then Nkind
(Name
(N
)) = N_Explicit_Dereference
3897 and then Comes_From_Source
(Name
(N
)))
3902 -- Mismatch in number or names of parameters
3904 elsif Debug_Flag_E
then
3905 Write_Str
(" normalization fails in call ");
3906 Write_Int
(Int
(N
));
3907 Write_Str
(" with subprogram ");
3908 Write_Int
(Int
(Nam
));
3912 -- If the context expects a function call, discard any interpretation
3913 -- that is a procedure. If the node is not overloaded, leave as is for
3914 -- better error reporting when type mismatch is found.
3916 elsif Nkind
(N
) = N_Function_Call
3917 and then Is_Overloaded
(Name
(N
))
3918 and then Ekind
(Nam
) = E_Procedure
3922 -- Ditto for function calls in a procedure context
3924 elsif Nkind
(N
) = N_Procedure_Call_Statement
3925 and then Is_Overloaded
(Name
(N
))
3926 and then Etype
(Nam
) /= Standard_Void_Type
3930 elsif No
(Actuals
) then
3932 -- If Normalize succeeds, then there are default parameters for
3935 Indicate_Name_And_Type
;
3937 elsif Ekind
(Nam
) = E_Operator
then
3938 if Nkind
(N
) = N_Procedure_Call_Statement
then
3942 -- This occurs when the prefix of the call is an operator name
3943 -- or an expanded name whose selector is an operator name.
3945 Analyze_Operator_Call
(N
, Nam
);
3947 if Etype
(N
) /= Prev_T
then
3949 -- Check that operator is not hidden by a function interpretation
3951 if Is_Overloaded
(Name
(N
)) then
3957 Get_First_Interp
(Name
(N
), I
, It
);
3958 while Present
(It
.Nam
) loop
3959 if Operator_Hidden_By
(It
.Nam
) then
3960 Set_Etype
(N
, Prev_T
);
3964 Get_Next_Interp
(I
, It
);
3969 -- If operator matches formals, record its name on the call.
3970 -- If the operator is overloaded, Resolve will select the
3971 -- correct one from the list of interpretations. The call
3972 -- node itself carries the first candidate.
3974 Set_Entity
(Name
(N
), Nam
);
3977 elsif Report
and then Etype
(N
) = Any_Type
then
3978 Error_Msg_N
("incompatible arguments for operator", N
);
3982 -- Normalize_Actuals has chained the named associations in the
3983 -- correct order of the formals.
3985 Actual
:= First_Actual
(N
);
3986 Formal
:= First_Formal
(Nam
);
3987 First_Form
:= Formal
;
3989 -- If we are analyzing a call rewritten from object notation, skip
3990 -- first actual, which may be rewritten later as an explicit
3994 Next_Actual
(Actual
);
3995 Next_Formal
(Formal
);
3998 while Present
(Actual
) and then Present
(Formal
) loop
3999 if Nkind
(Parent
(Actual
)) /= N_Parameter_Association
4000 or else Chars
(Selector_Name
(Parent
(Actual
))) = Chars
(Formal
)
4002 -- The actual can be compatible with the formal, but we must
4003 -- also check that the context is not an address type that is
4004 -- visibly an integer type. In this case the use of literals is
4005 -- illegal, except in the body of descendants of system, where
4006 -- arithmetic operations on address are of course used.
4008 if Has_Compatible_Type
(Actual
, Etype
(Formal
))
4010 (Etype
(Actual
) /= Universal_Integer
4011 or else not Is_Descendant_Of_Address
(Etype
(Formal
))
4012 or else In_Predefined_Unit
(N
))
4014 Next_Actual
(Actual
);
4015 Next_Formal
(Formal
);
4017 -- In Allow_Integer_Address mode, we allow an actual integer to
4018 -- match a formal address type and vice versa. We only do this
4019 -- if we are certain that an error will otherwise be issued
4021 elsif Address_Integer_Convert_OK
4022 (Etype
(Actual
), Etype
(Formal
))
4023 and then (Report
and not Is_Indexed
and not Is_Indirect
)
4025 -- Handle this case by introducing an unchecked conversion
4028 Unchecked_Convert_To
(Etype
(Formal
),
4029 Relocate_Node
(Actual
)));
4030 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
4031 Next_Actual
(Actual
);
4032 Next_Formal
(Formal
);
4034 -- Under relaxed RM semantics silently replace occurrences of
4035 -- null by System.Address_Null. We only do this if we know that
4036 -- an error will otherwise be issued.
4038 elsif Null_To_Null_Address_Convert_OK
(Actual
, Etype
(Formal
))
4039 and then (Report
and not Is_Indexed
and not Is_Indirect
)
4041 Replace_Null_By_Null_Address
(Actual
);
4042 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
4043 Next_Actual
(Actual
);
4044 Next_Formal
(Formal
);
4046 elsif Compatible_Types_In_Predicate
4047 (Etype
(Formal
), Etype
(Actual
))
4049 Next_Actual
(Actual
);
4050 Next_Formal
(Formal
);
4052 -- A current instance used as an actual of a function,
4053 -- whose body has not been seen, may include a formal
4054 -- whose type is an incomplete view of an enclosing
4055 -- type declaration containing the current call (e.g.
4056 -- in the Expression for a component declaration).
4058 -- In this case, update the signature of the subprogram
4059 -- so the formal has the type of the full view.
4061 elsif Inside_Init_Proc
4062 and then Nkind
(Actual
) = N_Identifier
4063 and then Ekind
(Etype
(Formal
)) = E_Incomplete_Type
4064 and then Etype
(Actual
) = Full_View
(Etype
(Formal
))
4066 Set_Etype
(Formal
, Etype
(Actual
));
4067 Next_Actual
(Actual
);
4068 Next_Formal
(Formal
);
4070 -- Handle failed type check
4073 if Debug_Flag_E
then
4074 Write_Str
(" type checking fails in call ");
4075 Write_Int
(Int
(N
));
4076 Write_Str
(" with formal ");
4077 Write_Int
(Int
(Formal
));
4078 Write_Str
(" in subprogram ");
4079 Write_Int
(Int
(Nam
));
4083 -- Comment needed on the following test???
4085 if Report
and not Is_Indexed
and not Is_Indirect
then
4087 -- Ada 2005 (AI-251): Complete the error notification
4088 -- to help new Ada 2005 users.
4090 if Is_Class_Wide_Type
(Etype
(Formal
))
4091 and then Is_Interface
(Etype
(Etype
(Formal
)))
4092 and then not Interface_Present_In_Ancestor
4093 (Typ
=> Etype
(Actual
),
4094 Iface
=> Etype
(Etype
(Formal
)))
4097 ("(Ada 2005) does not implement interface }",
4098 Actual
, Etype
(Etype
(Formal
)));
4101 -- If we are going to output a secondary error message
4102 -- below, we need to have Wrong_Type output the main one.
4105 (Actual
, Etype
(Formal
), Multiple
=> All_Errors_Mode
);
4107 if Nkind
(Actual
) = N_Op_Eq
4108 and then Nkind
(Left_Opnd
(Actual
)) = N_Identifier
4110 Formal
:= First_Formal
(Nam
);
4111 while Present
(Formal
) loop
4112 if Chars
(Left_Opnd
(Actual
)) = Chars
(Formal
) then
4113 Error_Msg_N
-- CODEFIX
4114 ("possible misspelling of `='>`!", Actual
);
4118 Next_Formal
(Formal
);
4122 if All_Errors_Mode
then
4123 Error_Msg_Sloc
:= Sloc
(Nam
);
4125 if Etype
(Formal
) = Any_Type
then
4127 ("there is no legal actual parameter", Actual
);
4130 if Is_Overloadable
(Nam
)
4131 and then Present
(Alias
(Nam
))
4132 and then not Comes_From_Source
(Nam
)
4135 ("\\ =='> in call to inherited operation & #!",
4138 elsif Ekind
(Nam
) = E_Subprogram_Type
then
4140 Access_To_Subprogram_Typ
:
4141 constant Entity_Id
:=
4143 (Associated_Node_For_Itype
(Nam
));
4146 ("\\ =='> in call to dereference of &#!",
4147 Actual
, Access_To_Subprogram_Typ
);
4152 ("\\ =='> in call to &#!", Actual
, Nam
);
4162 -- Normalize_Actuals has verified that a default value exists
4163 -- for this formal. Current actual names a subsequent formal.
4165 Next_Formal
(Formal
);
4169 -- Due to our current model of controlled type expansion we may
4170 -- have resolved a user call to a non-visible controlled primitive
4171 -- since these inherited subprograms may be generated in the current
4172 -- scope. This is a side effect of the need for the expander to be
4173 -- able to resolve internally generated calls.
4175 -- Specifically, the issue appears when predefined controlled
4176 -- operations get called on a type extension whose parent is a
4177 -- private extension completed with a controlled extension - see
4181 -- type Par_Typ is tagged private;
4183 -- type Par_Typ is new Controlled with null record;
4186 -- procedure Main is
4187 -- type Ext_Typ is new Par_Typ with null record;
4190 -- Finalize (Obj); -- Will improperly resolve
4193 -- To avoid breaking privacy, Is_Hidden gets set elsewhere on such
4194 -- primitives, but we still need to verify that Nam is indeed a
4195 -- non-visible controlled subprogram. So, we do that here and issue
4196 -- the appropriate error.
4199 and then not In_Instance
4200 and then not Comes_From_Source
(Nam
)
4201 and then Comes_From_Source
(N
)
4203 -- Verify Nam is a non-visible controlled primitive
4205 and then Chars
(Nam
) in Name_Adjust
4208 and then Ekind
(Nam
) = E_Procedure
4209 and then Is_Controlled
(Etype
(First_Form
))
4210 and then No
(Next_Formal
(First_Form
))
4211 and then not Is_Visibly_Controlled
(Etype
(First_Form
))
4213 Error_Msg_Node_2
:= Etype
(First_Form
);
4214 Error_Msg_NE
("call to non-visible controlled primitive & on type"
4218 -- On exit, all actuals match
4220 Indicate_Name_And_Type
;
4222 end Analyze_One_Call
;
4224 ---------------------------
4225 -- Analyze_Operator_Call --
4226 ---------------------------
4228 procedure Analyze_Operator_Call
(N
: Node_Id
; Op_Id
: Entity_Id
) is
4229 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
4230 Act1
: constant Node_Id
:= First_Actual
(N
);
4231 Act2
: constant Node_Id
:= Next_Actual
(Act1
);
4234 -- Binary operator case
4236 if Present
(Act2
) then
4238 -- If more than two operands, then not binary operator after all
4240 if Present
(Next_Actual
(Act2
)) then
4244 -- Otherwise action depends on operator
4255 Find_Arithmetic_Types
(Act1
, Act2
, Op_Id
, N
);
4261 Find_Boolean_Types
(Act1
, Act2
, Op_Id
, N
);
4270 Find_Comparison_Equality_Types
(Act1
, Act2
, Op_Id
, N
);
4272 when Name_Op_Concat
=>
4273 Find_Concatenation_Types
(Act1
, Act2
, Op_Id
, N
);
4275 -- Is this when others, or should it be an abort???
4281 -- Unary operator case
4289 Find_Unary_Types
(Act1
, Op_Id
, N
);
4292 Find_Negation_Types
(Act1
, Op_Id
, N
);
4294 -- Is this when others correct, or should it be an abort???
4300 end Analyze_Operator_Call
;
4302 -------------------------------------------
4303 -- Analyze_Overloaded_Selected_Component --
4304 -------------------------------------------
4306 procedure Analyze_Overloaded_Selected_Component
(N
: Node_Id
) is
4307 Nam
: constant Node_Id
:= Prefix
(N
);
4308 Sel
: constant Node_Id
:= Selector_Name
(N
);
4315 Set_Etype
(Sel
, Any_Type
);
4317 Get_First_Interp
(Nam
, I
, It
);
4318 while Present
(It
.Typ
) loop
4319 if Is_Access_Type
(It
.Typ
) then
4320 T
:= Designated_Type
(It
.Typ
);
4321 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
4326 -- Locate the component. For a private prefix the selector can denote
4329 if Is_Record_Type
(T
) or else Is_Private_Type
(T
) then
4331 -- If the prefix is a class-wide type, the visible components are
4332 -- those of the base type.
4334 if Is_Class_Wide_Type
(T
) then
4338 Comp
:= First_Entity
(T
);
4339 while Present
(Comp
) loop
4340 if Chars
(Comp
) = Chars
(Sel
)
4341 and then Is_Visible_Component
(Comp
, Sel
)
4344 -- AI05-105: if the context is an object renaming with
4345 -- an anonymous access type, the expected type of the
4346 -- object must be anonymous. This is a name resolution rule.
4348 if Nkind
(Parent
(N
)) /= N_Object_Renaming_Declaration
4349 or else No
(Access_Definition
(Parent
(N
)))
4350 or else Is_Anonymous_Access_Type
(Etype
(Comp
))
4352 Set_Entity
(Sel
, Comp
);
4353 Set_Etype
(Sel
, Etype
(Comp
));
4354 Add_One_Interp
(N
, Etype
(Comp
), Etype
(Comp
));
4355 Check_Implicit_Dereference
(N
, Etype
(Comp
));
4357 -- This also specifies a candidate to resolve the name.
4358 -- Further overloading will be resolved from context.
4359 -- The selector name itself does not carry overloading
4362 Set_Etype
(Nam
, It
.Typ
);
4365 -- Named access type in the context of a renaming
4366 -- declaration with an access definition. Remove
4367 -- inapplicable candidate.
4376 elsif Is_Concurrent_Type
(T
) then
4377 Comp
:= First_Entity
(T
);
4378 while Present
(Comp
)
4379 and then Comp
/= First_Private_Entity
(T
)
4381 if Chars
(Comp
) = Chars
(Sel
) then
4382 if Is_Overloadable
(Comp
) then
4383 Add_One_Interp
(Sel
, Comp
, Etype
(Comp
));
4385 Set_Entity_With_Checks
(Sel
, Comp
);
4386 Generate_Reference
(Comp
, Sel
);
4389 Set_Etype
(Sel
, Etype
(Comp
));
4390 Set_Etype
(N
, Etype
(Comp
));
4391 Set_Etype
(Nam
, It
.Typ
);
4397 Set_Is_Overloaded
(N
, Is_Overloaded
(Sel
));
4400 Get_Next_Interp
(I
, It
);
4403 if Etype
(N
) = Any_Type
4404 and then not Try_Object_Operation
(N
)
4406 Error_Msg_NE
("undefined selector& for overloaded prefix", N
, Sel
);
4407 Set_Entity
(Sel
, Any_Id
);
4408 Set_Etype
(Sel
, Any_Type
);
4410 end Analyze_Overloaded_Selected_Component
;
4412 ----------------------------------
4413 -- Analyze_Qualified_Expression --
4414 ----------------------------------
4416 procedure Analyze_Qualified_Expression
(N
: Node_Id
) is
4417 Expr
: constant Node_Id
:= Expression
(N
);
4418 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
4428 if Nkind
(Enclosing_Declaration
(N
)) in
4429 N_Formal_Type_Declaration |
4430 N_Full_Type_Declaration |
4431 N_Incomplete_Type_Declaration |
4432 N_Protected_Type_Declaration |
4433 N_Private_Extension_Declaration |
4434 N_Private_Type_Declaration |
4435 N_Subtype_Declaration |
4436 N_Task_Type_Declaration
4437 and then T
= Defining_Identifier
(Enclosing_Declaration
(N
))
4439 Error_Msg_N
("current instance not allowed", Mark
);
4445 Analyze_Expression
(Expr
);
4447 if T
= Any_Type
then
4451 Check_Fully_Declared
(T
, N
);
4453 -- If expected type is class-wide, check for exact match before
4454 -- expansion, because if the expression is a dispatching call it
4455 -- may be rewritten as explicit dereference with class-wide result.
4456 -- If expression is overloaded, retain only interpretations that
4457 -- will yield exact matches.
4459 if Is_Class_Wide_Type
(T
) then
4460 if not Is_Overloaded
(Expr
) then
4461 if Base_Type
(Etype
(Expr
)) /= Base_Type
(T
)
4462 and then Etype
(Expr
) /= Raise_Type
4464 if Nkind
(Expr
) = N_Aggregate
then
4465 Error_Msg_N
("type of aggregate cannot be class-wide", Expr
);
4467 Wrong_Type
(Expr
, T
);
4472 Get_First_Interp
(Expr
, I
, It
);
4474 while Present
(It
.Nam
) loop
4475 if Base_Type
(It
.Typ
) /= Base_Type
(T
) then
4479 Get_Next_Interp
(I
, It
);
4483 end Analyze_Qualified_Expression
;
4485 -----------------------------------
4486 -- Analyze_Quantified_Expression --
4487 -----------------------------------
4489 procedure Analyze_Quantified_Expression
(N
: Node_Id
) is
4490 function Is_Empty_Range
(Typ
: Entity_Id
) return Boolean;
4491 -- Return True if the iterator is part of a quantified expression and
4492 -- the range is known to be statically empty.
4494 function No_Else_Or_Trivial_True
(If_Expr
: Node_Id
) return Boolean;
4495 -- Determine whether if expression If_Expr lacks an else part or if it
4496 -- has one, it evaluates to True.
4498 --------------------
4499 -- Is_Empty_Range --
4500 --------------------
4502 function Is_Empty_Range
(Typ
: Entity_Id
) return Boolean is
4504 return Is_Array_Type
(Typ
)
4505 and then Compile_Time_Known_Bounds
(Typ
)
4507 Expr_Value
(Type_Low_Bound
(Etype
(First_Index
(Typ
)))) >
4508 Expr_Value
(Type_High_Bound
(Etype
(First_Index
(Typ
))));
4511 -----------------------------
4512 -- No_Else_Or_Trivial_True --
4513 -----------------------------
4515 function No_Else_Or_Trivial_True
(If_Expr
: Node_Id
) return Boolean is
4516 Else_Expr
: constant Node_Id
:=
4517 Next
(Next
(First
(Expressions
(If_Expr
))));
4521 or else (Compile_Time_Known_Value
(Else_Expr
)
4522 and then Is_True
(Expr_Value
(Else_Expr
)));
4523 end No_Else_Or_Trivial_True
;
4527 Cond
: constant Node_Id
:= Condition
(N
);
4528 Loc
: constant Source_Ptr
:= Sloc
(N
);
4529 Loop_Id
: Entity_Id
;
4530 QE_Scop
: Entity_Id
;
4532 -- Start of processing for Analyze_Quantified_Expression
4535 -- Create a scope to emulate the loop-like behavior of the quantified
4536 -- expression. The scope is needed to provide proper visibility of the
4539 QE_Scop
:= New_Internal_Entity
(E_Loop
, Current_Scope
, Loc
, 'L');
4540 Set_Etype
(QE_Scop
, Standard_Void_Type
);
4541 Set_Scope
(QE_Scop
, Current_Scope
);
4542 Set_Parent
(QE_Scop
, N
);
4544 Push_Scope
(QE_Scop
);
4546 -- All constituents are preanalyzed and resolved to avoid untimely
4547 -- generation of various temporaries and types. Full analysis and
4548 -- expansion is carried out when the quantified expression is
4549 -- transformed into an expression with actions.
4551 if Present
(Iterator_Specification
(N
)) then
4552 Preanalyze
(Iterator_Specification
(N
));
4554 -- Do not proceed with the analysis when the range of iteration is
4557 if Is_Entity_Name
(Name
(Iterator_Specification
(N
)))
4558 and then Is_Empty_Range
(Etype
(Name
(Iterator_Specification
(N
))))
4560 Preanalyze_And_Resolve
(Condition
(N
), Standard_Boolean
);
4563 -- Emit a warning and replace expression with its static value
4565 if All_Present
(N
) then
4567 ("??quantified expression with ALL "
4568 & "over a null range has value True", N
);
4569 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
4573 ("??quantified expression with SOME "
4574 & "over a null range has value False", N
);
4575 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
4582 else pragma Assert
(Present
(Loop_Parameter_Specification
(N
)));
4584 Loop_Par
: constant Node_Id
:= Loop_Parameter_Specification
(N
);
4587 Preanalyze
(Loop_Par
);
4589 if Nkind
(Discrete_Subtype_Definition
(Loop_Par
)) = N_Function_Call
4590 and then Parent
(Loop_Par
) /= N
4592 -- The parser cannot distinguish between a loop specification
4593 -- and an iterator specification. If after preanalysis the
4594 -- proper form has been recognized, rewrite the expression to
4595 -- reflect the right kind. This is needed for proper ASIS
4596 -- navigation. If expansion is enabled, the transformation is
4597 -- performed when the expression is rewritten as a loop.
4598 -- Is this still needed???
4600 Set_Iterator_Specification
(N
,
4601 New_Copy_Tree
(Iterator_Specification
(Parent
(Loop_Par
))));
4603 Set_Defining_Identifier
(Iterator_Specification
(N
),
4604 Relocate_Node
(Defining_Identifier
(Loop_Par
)));
4605 Set_Name
(Iterator_Specification
(N
),
4606 Relocate_Node
(Discrete_Subtype_Definition
(Loop_Par
)));
4607 Set_Comes_From_Source
(Iterator_Specification
(N
),
4608 Comes_From_Source
(Loop_Parameter_Specification
(N
)));
4609 Set_Loop_Parameter_Specification
(N
, Empty
);
4614 Preanalyze_And_Resolve
(Cond
, Standard_Boolean
);
4617 Set_Etype
(N
, Standard_Boolean
);
4619 -- Verify that the loop variable is used within the condition of the
4620 -- quantified expression.
4622 if Present
(Iterator_Specification
(N
)) then
4623 Loop_Id
:= Defining_Identifier
(Iterator_Specification
(N
));
4625 Loop_Id
:= Defining_Identifier
(Loop_Parameter_Specification
(N
));
4629 type Subexpr_Kind
is (Full
, Conjunct
, Disjunct
);
4631 procedure Check_Subexpr
(Expr
: Node_Id
; Kind
: Subexpr_Kind
);
4632 -- Check that the quantified variable appears in every sub-expression
4633 -- of the quantified expression. If Kind is Full, Expr is the full
4634 -- expression. If Kind is Conjunct (resp. Disjunct), Expr is a
4635 -- conjunct (resp. disjunct) of the full expression.
4641 procedure Check_Subexpr
(Expr
: Node_Id
; Kind
: Subexpr_Kind
) is
4643 if Nkind
(Expr
) in N_Op_And | N_And_Then
4644 and then Kind
/= Disjunct
4646 Check_Subexpr
(Left_Opnd
(Expr
), Conjunct
);
4647 Check_Subexpr
(Right_Opnd
(Expr
), Conjunct
);
4649 elsif Nkind
(Expr
) in N_Op_Or | N_Or_Else
4650 and then Kind
/= Conjunct
4652 Check_Subexpr
(Left_Opnd
(Expr
), Disjunct
);
4653 Check_Subexpr
(Right_Opnd
(Expr
), Disjunct
);
4656 and then not Referenced
(Loop_Id
, Expr
)
4659 Sub
: constant String :=
4660 (if Kind
= Conjunct
then "conjunct" else "disjunct");
4663 ("?.t?unused variable & in " & Sub
, Expr
, Loop_Id
);
4665 ("\consider extracting " & Sub
& " from quantified "
4666 & "expression", Expr
, Loop_Id
);
4672 if Warn_On_Suspicious_Contract
4673 and then not Is_Internal_Name
(Chars
(Loop_Id
))
4675 -- Generating C, this check causes spurious warnings on inlined
4676 -- postconditions; we can safely disable it because this check
4677 -- was previously performed when analyzing the internally built
4678 -- postconditions procedure.
4680 and then not (Modify_Tree_For_C
and In_Inlined_Body
)
4682 if not Referenced
(Loop_Id
, Cond
) then
4683 Error_Msg_N
("?.t?unused variable &", Loop_Id
);
4685 Check_Subexpr
(Cond
, Kind
=> Full
);
4690 -- Diagnose a possible misuse of the SOME existential quantifier. When
4691 -- we have a quantified expression of the form:
4693 -- for some X => (if P then Q [else True])
4695 -- any value for X that makes P False results in the if expression being
4696 -- trivially True, and so also results in the quantified expression
4697 -- being trivially True.
4699 if Warn_On_Suspicious_Contract
4700 and then not All_Present
(N
)
4701 and then Nkind
(Cond
) = N_If_Expression
4702 and then No_Else_Or_Trivial_True
(Cond
)
4704 Error_Msg_N
("?.t?suspicious expression", N
);
4705 Error_Msg_N
("\\did you mean (for all X ='> (if P then Q))", N
);
4706 Error_Msg_N
("\\or (for some X ='> P and then Q) instead'?", N
);
4708 end Analyze_Quantified_Expression
;
4714 procedure Analyze_Range
(N
: Node_Id
) is
4715 L
: constant Node_Id
:= Low_Bound
(N
);
4716 H
: constant Node_Id
:= High_Bound
(N
);
4717 I1
, I2
: Interp_Index
;
4720 procedure Check_Common_Type
(T1
, T2
: Entity_Id
);
4721 -- Verify the compatibility of two types, and choose the
4722 -- non universal one if the other is universal.
4724 procedure Check_High_Bound
(T
: Entity_Id
);
4725 -- Test one interpretation of the low bound against all those
4726 -- of the high bound.
4728 procedure Check_Universal_Expression
(N
: Node_Id
);
4729 -- In Ada 83, reject bounds of a universal range that are not literals
4732 -----------------------
4733 -- Check_Common_Type --
4734 -----------------------
4736 procedure Check_Common_Type
(T1
, T2
: Entity_Id
) is
4738 if Covers
(T1
=> T1
, T2
=> T2
)
4740 Covers
(T1
=> T2
, T2
=> T1
)
4742 if Is_Universal_Numeric_Type
(T1
)
4743 or else T1
= Any_Character
4745 Add_One_Interp
(N
, Base_Type
(T2
), Base_Type
(T2
));
4748 Add_One_Interp
(N
, T1
, T1
);
4751 Add_One_Interp
(N
, Base_Type
(T1
), Base_Type
(T1
));
4754 end Check_Common_Type
;
4756 ----------------------
4757 -- Check_High_Bound --
4758 ----------------------
4760 procedure Check_High_Bound
(T
: Entity_Id
) is
4762 if not Is_Overloaded
(H
) then
4763 Check_Common_Type
(T
, Etype
(H
));
4765 Get_First_Interp
(H
, I2
, It2
);
4766 while Present
(It2
.Typ
) loop
4767 Check_Common_Type
(T
, It2
.Typ
);
4768 Get_Next_Interp
(I2
, It2
);
4771 end Check_High_Bound
;
4773 --------------------------------
4774 -- Check_Universal_Expression --
4775 --------------------------------
4777 procedure Check_Universal_Expression
(N
: Node_Id
) is
4779 if Etype
(N
) = Universal_Integer
4780 and then Nkind
(N
) /= N_Integer_Literal
4781 and then not Is_Entity_Name
(N
)
4782 and then Nkind
(N
) /= N_Attribute_Reference
4784 Error_Msg_N
("illegal bound in discrete range", N
);
4786 end Check_Universal_Expression
;
4788 -- Start of processing for Analyze_Range
4791 Set_Etype
(N
, Any_Type
);
4792 Analyze_Expression
(L
);
4793 Analyze_Expression
(H
);
4795 if Etype
(L
) = Any_Type
or else Etype
(H
) = Any_Type
then
4799 if not Is_Overloaded
(L
) then
4800 Check_High_Bound
(Etype
(L
));
4802 Get_First_Interp
(L
, I1
, It1
);
4803 while Present
(It1
.Typ
) loop
4804 Check_High_Bound
(It1
.Typ
);
4805 Get_Next_Interp
(I1
, It1
);
4809 -- If result is Any_Type, then we did not find a compatible pair
4811 if Etype
(N
) = Any_Type
then
4812 Error_Msg_N
("incompatible types in range", N
);
4816 if Ada_Version
= Ada_83
4818 (Nkind
(Parent
(N
)) = N_Loop_Parameter_Specification
4819 or else Nkind
(Parent
(N
)) = N_Constrained_Array_Definition
)
4821 Check_Universal_Expression
(L
);
4822 Check_Universal_Expression
(H
);
4825 Check_Function_Writable_Actuals
(N
);
4828 -----------------------
4829 -- Analyze_Reference --
4830 -----------------------
4832 procedure Analyze_Reference
(N
: Node_Id
) is
4833 P
: constant Node_Id
:= Prefix
(N
);
4836 Acc_Type
: Entity_Id
;
4841 -- An interesting error check, if we take the 'Ref of an object for
4842 -- which a pragma Atomic or Volatile has been given, and the type of the
4843 -- object is not Atomic or Volatile, then we are in trouble. The problem
4844 -- is that no trace of the atomic/volatile status will remain for the
4845 -- backend to respect when it deals with the resulting pointer, since
4846 -- the pointer type will not be marked atomic (it is a pointer to the
4847 -- base type of the object).
4849 -- It is not clear if that can ever occur, but in case it does, we will
4850 -- generate an error message. Not clear if this message can ever be
4851 -- generated, and pretty clear that it represents a bug if it is, still
4852 -- seems worth checking, except in CodePeer mode where we do not really
4853 -- care and don't want to bother the user.
4857 if Is_Entity_Name
(P
)
4858 and then Is_Object_Reference
(P
)
4859 and then not CodePeer_Mode
4864 if (Has_Atomic_Components
(E
)
4865 and then not Has_Atomic_Components
(T
))
4867 (Has_Volatile_Components
(E
)
4868 and then not Has_Volatile_Components
(T
))
4869 or else (Is_Atomic
(E
) and then not Is_Atomic
(T
))
4870 or else (Is_Volatile
(E
) and then not Is_Volatile
(T
))
4872 Error_Msg_N
("cannot take reference to Atomic/Volatile object", N
);
4876 -- Carry on with normal processing
4878 Acc_Type
:= Create_Itype
(E_Allocator_Type
, N
);
4879 Set_Etype
(Acc_Type
, Acc_Type
);
4880 Set_Directly_Designated_Type
(Acc_Type
, Etype
(P
));
4881 Set_Etype
(N
, Acc_Type
);
4882 end Analyze_Reference
;
4884 --------------------------------
4885 -- Analyze_Selected_Component --
4886 --------------------------------
4888 -- Prefix is a record type or a task or protected type. In the latter case,
4889 -- the selector must denote a visible entry.
4891 procedure Analyze_Selected_Component
(N
: Node_Id
) is
4892 Name
: constant Node_Id
:= Prefix
(N
);
4893 Sel
: constant Node_Id
:= Selector_Name
(N
);
4895 Comp
: Entity_Id
:= Empty
;
4896 Has_Candidate
: Boolean := False;
4897 Hidden_Comp
: Entity_Id
;
4899 Is_Private_Op
: Boolean;
4901 Prefix_Type
: Entity_Id
;
4903 Type_To_Use
: Entity_Id
;
4904 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
4905 -- a class-wide type, we use its root type, whose components are
4906 -- present in the class-wide type.
4908 Is_Single_Concurrent_Object
: Boolean;
4909 -- Set True if the prefix is a single task or a single protected object
4911 function Constraint_Has_Unprefixed_Discriminant_Reference
4912 (Typ
: Entity_Id
) return Boolean;
4913 -- Given a subtype that is subject to a discriminant-dependent
4914 -- constraint, returns True if any of the values of the constraint
4915 -- (i.e., any of the index values for an index constraint, any of
4916 -- the discriminant values for a discriminant constraint)
4917 -- are unprefixed discriminant names.
4919 function Has_Mode_Conformant_Spec
(Comp
: Entity_Id
) return Boolean;
4920 -- It is known that the parent of N denotes a subprogram call. Comp
4921 -- is an overloadable component of the concurrent type of the prefix.
4922 -- Determine whether all formals of the parent of N and Comp are mode
4923 -- conformant. If the parent node is not analyzed yet it may be an
4924 -- indexed component rather than a function call.
4926 function Has_Dereference
(Nod
: Node_Id
) return Boolean;
4927 -- Check whether prefix includes a dereference, explicit or implicit,
4928 -- at any recursive level.
4930 function Try_By_Protected_Procedure_Prefixed_View
return Boolean;
4931 -- Return True if N is an access attribute whose prefix is a prefixed
4932 -- class-wide (synchronized or protected) interface view for which some
4933 -- interpretation is a procedure with synchronization kind By_Protected
4934 -- _Procedure, and collect all its interpretations (since it may be an
4935 -- overloaded interface primitive); otherwise return False.
4937 function Try_Selected_Component_In_Instance
4938 (Typ
: Entity_Id
) return Boolean;
4939 -- If Typ is the actual for a formal derived type, or a derived type
4940 -- thereof, the component inherited from the generic parent may not
4941 -- be visible in the actual, but the selected component is legal. Climb
4942 -- up the derivation chain of the generic parent type and return True if
4943 -- we find the proper ancestor type; otherwise return False.
4945 ------------------------------------------------------
4946 -- Constraint_Has_Unprefixed_Discriminant_Reference --
4947 ------------------------------------------------------
4949 function Constraint_Has_Unprefixed_Discriminant_Reference
4950 (Typ
: Entity_Id
) return Boolean
4952 function Is_Discriminant_Name
(N
: Node_Id
) return Boolean is
4953 (Nkind
(N
) = N_Identifier
4954 and then Ekind
(Entity
(N
)) = E_Discriminant
);
4956 if Is_Array_Type
(Typ
) then
4958 Index
: Node_Id
:= First_Index
(Typ
);
4961 while Present
(Index
) loop
4963 if Nkind
(Rng
) = N_Subtype_Indication
then
4964 Rng
:= Range_Expression
(Constraint
(Rng
));
4967 if Nkind
(Rng
) = N_Range
then
4968 if Is_Discriminant_Name
(Low_Bound
(Rng
))
4969 or else Is_Discriminant_Name
(High_Bound
(Rng
))
4980 Elmt
: Elmt_Id
:= First_Elmt
(Discriminant_Constraint
(Typ
));
4982 while Present
(Elmt
) loop
4983 if Is_Discriminant_Name
(Node
(Elmt
)) then
4992 end Constraint_Has_Unprefixed_Discriminant_Reference
;
4994 ------------------------------
4995 -- Has_Mode_Conformant_Spec --
4996 ------------------------------
4998 function Has_Mode_Conformant_Spec
(Comp
: Entity_Id
) return Boolean is
4999 Comp_Param
: Entity_Id
;
5001 Param_Typ
: Entity_Id
;
5004 Comp_Param
:= First_Formal
(Comp
);
5006 if Nkind
(Parent
(N
)) = N_Indexed_Component
then
5007 Param
:= First
(Expressions
(Parent
(N
)));
5009 Param
:= First
(Parameter_Associations
(Parent
(N
)));
5012 while Present
(Comp_Param
)
5013 and then Present
(Param
)
5015 Param_Typ
:= Find_Parameter_Type
(Param
);
5017 if Present
(Param_Typ
)
5019 not Conforming_Types
5020 (Etype
(Comp_Param
), Param_Typ
, Mode_Conformant
)
5025 Next_Formal
(Comp_Param
);
5029 -- One of the specs has additional formals; there is no match, unless
5030 -- this may be an indexing of a parameterless call.
5032 -- Note that when expansion is disabled, the corresponding record
5033 -- type of synchronized types is not constructed, so that there is
5034 -- no point is attempting an interpretation as a prefixed call, as
5035 -- this is bound to fail because the primitive operations will not
5036 -- be properly located.
5038 if Present
(Comp_Param
) or else Present
(Param
) then
5039 if Needs_No_Actuals
(Comp
)
5040 and then Is_Array_Type
(Etype
(Comp
))
5041 and then not Expander_Active
5050 end Has_Mode_Conformant_Spec
;
5052 ---------------------
5053 -- Has_Dereference --
5054 ---------------------
5056 function Has_Dereference
(Nod
: Node_Id
) return Boolean is
5058 if Nkind
(Nod
) = N_Explicit_Dereference
then
5061 elsif Is_Access_Type
(Etype
(Nod
)) then
5064 elsif Nkind
(Nod
) in N_Indexed_Component | N_Selected_Component
then
5065 return Has_Dereference
(Prefix
(Nod
));
5070 end Has_Dereference
;
5072 ----------------------------------------------
5073 -- Try_By_Protected_Procedure_Prefixed_View --
5074 ----------------------------------------------
5076 function Try_By_Protected_Procedure_Prefixed_View
return Boolean is
5077 Candidate
: Node_Id
:= Empty
;
5082 if Nkind
(Parent
(N
)) = N_Attribute_Reference
5083 and then Attribute_Name
(Parent
(N
)) in
5085 | Name_Unchecked_Access
5086 | Name_Unrestricted_Access
5087 and then Is_Class_Wide_Type
(Prefix_Type
)
5088 and then (Is_Synchronized_Interface
(Prefix_Type
)
5089 or else Is_Protected_Interface
(Prefix_Type
))
5091 -- If we have not found yet any interpretation then mark this
5092 -- one as the first interpretation (cf. Add_One_Interp).
5094 if No
(Etype
(Sel
)) then
5095 Set_Etype
(Sel
, Any_Type
);
5098 Elmt
:= First_Elmt
(Primitive_Operations
(Etype
(Prefix_Type
)));
5099 while Present
(Elmt
) loop
5100 Prim
:= Node
(Elmt
);
5102 if Chars
(Prim
) = Chars
(Sel
)
5103 and then Is_By_Protected_Procedure
(Prim
)
5105 Candidate
:= New_Copy
(Prim
);
5107 -- Skip the controlling formal; required to check type
5108 -- conformance of the target access to protected type
5109 -- (see Conforming_Types).
5111 Set_First_Entity
(Candidate
,
5112 Next_Entity
(First_Entity
(Prim
)));
5114 Add_One_Interp
(Sel
, Candidate
, Etype
(Prim
));
5115 Set_Etype
(N
, Etype
(Prim
));
5122 -- Propagate overloaded attribute
5124 if Present
(Candidate
) and then Is_Overloaded
(Sel
) then
5125 Set_Is_Overloaded
(N
);
5128 return Present
(Candidate
);
5129 end Try_By_Protected_Procedure_Prefixed_View
;
5131 ----------------------------------------
5132 -- Try_Selected_Component_In_Instance --
5133 ----------------------------------------
5135 function Try_Selected_Component_In_Instance
5136 (Typ
: Entity_Id
) return Boolean
5138 procedure Find_Component_In_Instance
(Rec
: Entity_Id
);
5139 -- In an instance, a component of a private extension may not be
5140 -- visible while it was visible in the generic. Search candidate
5141 -- scope for a component with the proper identifier. If a match is
5142 -- found, the Etype of both N and Sel are set from this component,
5143 -- and the entity of Sel is set to reference this component. If no
5144 -- match is found, Entity (Sel) remains unset. For a derived type
5145 -- that is an actual of the instance, the desired component may be
5146 -- found in any ancestor.
5148 --------------------------------
5149 -- Find_Component_In_Instance --
5150 --------------------------------
5152 procedure Find_Component_In_Instance
(Rec
: Entity_Id
) is
5158 while Present
(Typ
) loop
5159 Comp
:= First_Component
(Typ
);
5160 while Present
(Comp
) loop
5161 if Chars
(Comp
) = Chars
(Sel
) then
5162 Set_Entity_With_Checks
(Sel
, Comp
);
5163 Set_Etype
(Sel
, Etype
(Comp
));
5164 Set_Etype
(N
, Etype
(Comp
));
5168 Next_Component
(Comp
);
5171 -- If not found, the component may be declared in the parent
5172 -- type or its full view, if any.
5174 if Is_Derived_Type
(Typ
) then
5177 if Is_Private_Type
(Typ
) then
5178 Typ
:= Full_View
(Typ
);
5186 -- If we fall through, no match, so no changes made
5189 end Find_Component_In_Instance
;
5195 -- Start of processing for Try_Selected_Component_In_Instance
5198 pragma Assert
(In_Instance
and then Is_Tagged_Type
(Typ
));
5199 pragma Assert
(Etype
(N
) = Any_Type
);
5201 -- Climb up derivation chain to generic actual subtype
5204 while not Is_Generic_Actual_Type
(Par
) loop
5205 if Ekind
(Par
) = E_Record_Type
then
5206 Par
:= Parent_Subtype
(Par
);
5209 exit when Par
= Etype
(Par
);
5214 -- If Par is a generic actual, look for component in ancestor types.
5215 -- Skip this if we have no Declaration_Node, as is the case for
5219 and then Is_Generic_Actual_Type
(Par
)
5220 and then Present
(Declaration_Node
(Par
))
5222 Par
:= Generic_Parent_Type
(Declaration_Node
(Par
));
5224 Find_Component_In_Instance
(Par
);
5225 exit when Present
(Entity
(Sel
))
5226 or else Par
= Etype
(Par
);
5230 -- Another special case: the type is an extension of a private
5231 -- type T, either is an actual in an instance or is immediately
5232 -- visible, and we are in the body of the instance, which means
5233 -- the generic body had a full view of the type declaration for
5234 -- T or some ancestor that defines the component in question.
5235 -- This happens because Is_Visible_Component returned False on
5236 -- this component, as T or the ancestor is still private since
5237 -- the Has_Private_View mechanism is bypassed because T or the
5238 -- ancestor is not directly referenced in the generic body.
5240 elsif Is_Derived_Type
(Typ
)
5241 and then (Used_As_Generic_Actual
(Typ
)
5242 or else Is_Immediately_Visible
(Typ
))
5243 and then In_Instance_Body
5245 Find_Component_In_Instance
(Parent_Subtype
(Typ
));
5248 return Etype
(N
) /= Any_Type
;
5249 end Try_Selected_Component_In_Instance
;
5251 -- Start of processing for Analyze_Selected_Component
5254 Set_Etype
(N
, Any_Type
);
5256 if Is_Overloaded
(Name
) then
5257 Analyze_Overloaded_Selected_Component
(N
);
5260 elsif Etype
(Name
) = Any_Type
then
5261 Set_Entity
(Sel
, Any_Id
);
5262 Set_Etype
(Sel
, Any_Type
);
5266 Prefix_Type
:= Etype
(Name
);
5269 if Is_Access_Type
(Prefix_Type
) then
5271 -- A RACW object can never be used as prefix of a selected component
5272 -- since that means it is dereferenced without being a controlling
5273 -- operand of a dispatching operation (RM E.2.2(16/1)). Before
5274 -- reporting an error, we must check whether this is actually a
5275 -- dispatching call in prefix form.
5277 if Is_Remote_Access_To_Class_Wide_Type
(Prefix_Type
)
5278 and then Comes_From_Source
(N
)
5280 if Try_Object_Operation
(N
) then
5284 ("invalid dereference of a remote access-to-class-wide value",
5288 -- Normal case of selected component applied to access type
5291 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
5292 Prefix_Type
:= Implicitly_Designated_Type
(Prefix_Type
);
5295 -- If we have an explicit dereference of a remote access-to-class-wide
5296 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
5297 -- have to check for the case of a prefix that is a controlling operand
5298 -- of a prefixed dispatching call, as the dereference is legal in that
5299 -- case. Normally this condition is checked in Validate_Remote_Access_
5300 -- To_Class_Wide_Type, but we have to defer the checking for selected
5301 -- component prefixes because of the prefixed dispatching call case.
5302 -- Note that implicit dereferences are checked for this just above.
5304 elsif Nkind
(Name
) = N_Explicit_Dereference
5305 and then Is_Remote_Access_To_Class_Wide_Type
(Etype
(Prefix
(Name
)))
5306 and then Comes_From_Source
(N
)
5308 if Try_Object_Operation
(N
) then
5312 ("invalid dereference of a remote access-to-class-wide value",
5317 -- (Ada 2005): if the prefix is the limited view of a type, and
5318 -- the context already includes the full view, use the full view
5319 -- in what follows, either to retrieve a component of to find
5320 -- a primitive operation. If the prefix is an explicit dereference,
5321 -- set the type of the prefix to reflect this transformation.
5322 -- If the nonlimited view is itself an incomplete type, get the
5323 -- full view if available.
5325 if From_Limited_With
(Prefix_Type
)
5326 and then Has_Non_Limited_View
(Prefix_Type
)
5328 Prefix_Type
:= Get_Full_View
(Non_Limited_View
(Prefix_Type
));
5330 if Nkind
(N
) = N_Explicit_Dereference
then
5331 Set_Etype
(Prefix
(N
), Prefix_Type
);
5335 if Ekind
(Prefix_Type
) = E_Private_Subtype
then
5336 Prefix_Type
:= Base_Type
(Prefix_Type
);
5339 Type_To_Use
:= Prefix_Type
;
5341 -- For class-wide types, use the entity list of the root type. This
5342 -- indirection is specially important for private extensions because
5343 -- only the root type get switched (not the class-wide type).
5345 if Is_Class_Wide_Type
(Prefix_Type
) then
5346 Type_To_Use
:= Root_Type
(Prefix_Type
);
5349 -- If the prefix is a single concurrent object, use its name in error
5350 -- messages, rather than that of its anonymous type.
5352 Is_Single_Concurrent_Object
:=
5353 Is_Concurrent_Type
(Prefix_Type
)
5354 and then Is_Internal_Name
(Chars
(Prefix_Type
))
5355 and then not Is_Derived_Type
(Prefix_Type
)
5356 and then Is_Entity_Name
(Name
);
5358 -- Avoid initializing Comp if that initialization is not needed
5359 -- (and, more importantly, if the call to First_Entity could fail).
5361 if Has_Discriminants
(Type_To_Use
)
5362 or else Is_Record_Type
(Type_To_Use
)
5363 or else Is_Private_Type
(Type_To_Use
)
5364 or else Is_Concurrent_Type
(Type_To_Use
)
5366 Comp
:= First_Entity
(Type_To_Use
);
5369 -- If the selector has an original discriminant, the node appears in
5370 -- an instance. Replace the discriminant with the corresponding one
5371 -- in the current discriminated type. For nested generics, this must
5372 -- be done transitively, so note the new original discriminant.
5374 if Nkind
(Sel
) = N_Identifier
5375 and then In_Instance
5376 and then Present
(Original_Discriminant
(Sel
))
5378 Comp
:= Find_Corresponding_Discriminant
(Sel
, Prefix_Type
);
5380 -- Mark entity before rewriting, for completeness and because
5381 -- subsequent semantic checks might examine the original node.
5383 Set_Entity
(Sel
, Comp
);
5384 Rewrite
(Selector_Name
(N
), New_Occurrence_Of
(Comp
, Sloc
(N
)));
5385 Set_Original_Discriminant
(Selector_Name
(N
), Comp
);
5386 Set_Etype
(N
, Etype
(Comp
));
5387 Check_Implicit_Dereference
(N
, Etype
(Comp
));
5389 elsif Is_Record_Type
(Prefix_Type
) then
5391 -- Find a component with the given name. If the node is a prefixed
5392 -- call, do not examine components whose visibility may be
5395 while Present
(Comp
)
5396 and then not Is_Prefixed_Call
(N
)
5398 -- When the selector has been resolved to a function then we may be
5399 -- looking at a prefixed call which has been preanalyzed already as
5400 -- part of a class condition. In such cases it is possible for a
5401 -- derived type to declare a component which has the same name as
5402 -- a primitive used in a parent's class condition.
5404 -- Avoid seeing components as possible interpretations of the
5405 -- selected component when this is true.
5407 and then not (Inside_Class_Condition_Preanalysis
5408 and then Present
(Entity
(Sel
))
5409 and then Ekind
(Entity
(Sel
)) = E_Function
)
5411 if Chars
(Comp
) = Chars
(Sel
)
5412 and then Is_Visible_Component
(Comp
, N
)
5414 Set_Entity_With_Checks
(Sel
, Comp
);
5415 Set_Etype
(Sel
, Etype
(Comp
));
5417 if Ekind
(Comp
) = E_Discriminant
then
5418 if Is_Unchecked_Union
(Base_Type
(Prefix_Type
)) then
5420 ("cannot reference discriminant of unchecked union",
5424 if Is_Generic_Type
(Prefix_Type
)
5426 Is_Generic_Type
(Root_Type
(Prefix_Type
))
5428 Set_Original_Discriminant
(Sel
, Comp
);
5432 -- Resolve the prefix early otherwise it is not possible to
5433 -- build the actual subtype of the component: it may need
5434 -- to duplicate this prefix and duplication is only allowed
5435 -- on fully resolved expressions.
5439 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
5440 -- subtypes in a package specification.
5443 -- limited with Pkg;
5445 -- type Acc_Inc is access Pkg.T;
5447 -- N : Natural := X.all.Comp; -- ERROR, limited view
5448 -- end Pkg; -- Comp is not visible
5450 if Nkind
(Name
) = N_Explicit_Dereference
5451 and then From_Limited_With
(Etype
(Prefix
(Name
)))
5452 and then not Is_Potentially_Use_Visible
(Etype
(Name
))
5453 and then Nkind
(Parent
(Cunit_Entity
(Current_Sem_Unit
))) =
5454 N_Package_Specification
5457 ("premature usage of incomplete}", Prefix
(Name
),
5458 Etype
(Prefix
(Name
)));
5461 -- We never need an actual subtype for the case of a selection
5462 -- for a indexed component of a non-packed array, since in
5463 -- this case gigi generates all the checks and can find the
5464 -- necessary bounds information.
5466 -- We also do not need an actual subtype for the case of a
5467 -- first, last, length, or range attribute applied to a
5468 -- non-packed array, since gigi can again get the bounds in
5469 -- these cases (gigi cannot handle the packed case, since it
5470 -- has the bounds of the packed array type, not the original
5471 -- bounds of the type). However, if the prefix is itself a
5472 -- selected component, as in a.b.c (i), gigi may regard a.b.c
5473 -- as a dynamic-sized temporary, so we do generate an actual
5474 -- subtype for this case.
5476 Parent_N
:= Parent
(N
);
5478 if not Is_Packed
(Etype
(Comp
))
5480 ((Nkind
(Parent_N
) = N_Indexed_Component
5481 and then Nkind
(Name
) /= N_Selected_Component
)
5483 (Nkind
(Parent_N
) = N_Attribute_Reference
5485 Attribute_Name
(Parent_N
) in Name_First
5490 Set_Etype
(N
, Etype
(Comp
));
5492 -- If full analysis is not enabled, we do not generate an
5493 -- actual subtype, because in the absence of expansion
5494 -- reference to a formal of a protected type, for example,
5495 -- will not be properly transformed, and will lead to
5496 -- out-of-scope references in gigi.
5498 -- In all other cases, we currently build an actual subtype.
5499 -- It seems likely that many of these cases can be avoided,
5500 -- but right now, the front end makes direct references to the
5501 -- bounds (e.g. in generating a length check), and if we do
5502 -- not make an actual subtype, we end up getting a direct
5503 -- reference to a discriminant, which will not do.
5505 elsif Full_Analysis
then
5507 Build_Actual_Subtype_Of_Component
(Etype
(Comp
), N
);
5508 Insert_Action
(N
, Act_Decl
);
5510 if No
(Act_Decl
) then
5511 Set_Etype
(N
, Etype
(Comp
));
5514 -- If discriminants were present in the component
5515 -- declaration, they have been replaced by the
5516 -- actual values in the prefix object.
5519 Subt
: constant Entity_Id
:=
5520 Defining_Identifier
(Act_Decl
);
5522 Set_Etype
(Subt
, Base_Type
(Etype
(Comp
)));
5523 Set_Etype
(N
, Subt
);
5527 -- If Etype (Comp) is an access type whose designated subtype
5528 -- is constrained by an unprefixed discriminant value,
5529 -- then ideally we would build a new subtype with an
5530 -- appropriately prefixed discriminant value and use that
5531 -- instead, as is done in Build_Actual_Subtype_Of_Component.
5532 -- That turns out to be difficult in this context (with
5533 -- Full_Analysis = False, we could be processing a selected
5534 -- component that occurs in a Postcondition pragma;
5535 -- PPC pragmas are odd because they can contain references
5536 -- to formal parameters that occur outside the subprogram).
5537 -- So instead we punt on building a new subtype and we
5538 -- use the base type instead. This might introduce
5539 -- correctness problems if N were the target of an
5540 -- assignment (because a required check might be omitted);
5541 -- fortunately, that's impossible because a reference to the
5542 -- current instance of a type does not denote a variable view
5543 -- when the reference occurs within an aspect_specification.
5544 -- GNAT's Precondition and Postcondition pragmas follow the
5545 -- same rules as a Pre or Post aspect_specification.
5547 elsif Has_Discriminant_Dependent_Constraint
(Comp
)
5548 and then Ekind
(Etype
(Comp
)) = E_Access_Subtype
5549 and then Constraint_Has_Unprefixed_Discriminant_Reference
5550 (Designated_Type
(Etype
(Comp
)))
5552 Set_Etype
(N
, Base_Type
(Etype
(Comp
)));
5554 -- If Full_Analysis not enabled, just set the Etype
5557 Set_Etype
(N
, Etype
(Comp
));
5560 Check_Implicit_Dereference
(N
, Etype
(N
));
5564 -- If the prefix is a private extension, check only the visible
5565 -- components of the partial view. This must include the tag,
5566 -- which can appear in expanded code in a tag check.
5568 if Ekind
(Type_To_Use
) = E_Record_Type_With_Private
5569 and then Chars
(Selector_Name
(N
)) /= Name_uTag
5571 exit when Comp
= Last_Entity
(Type_To_Use
);
5577 -- Ada 2005 (AI-252): The selected component can be interpreted as
5578 -- a prefixed view of a subprogram. Depending on the context, this is
5579 -- either a name that can appear in a renaming declaration, or part
5580 -- of an enclosing call given in prefix form.
5582 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
5583 -- selected component should resolve to a name.
5585 -- Extension feature: Also support calls with prefixed views for
5586 -- untagged record types.
5588 if Ada_Version
>= Ada_2005
5589 and then (Is_Tagged_Type
(Prefix_Type
)
5590 or else Core_Extensions_Allowed
)
5591 and then not Is_Concurrent_Type
(Prefix_Type
)
5593 if Nkind
(Parent
(N
)) = N_Generic_Association
5594 or else Nkind
(Parent
(N
)) = N_Requeue_Statement
5595 or else Nkind
(Parent
(N
)) = N_Subprogram_Renaming_Declaration
5597 if Find_Primitive_Operation
(N
) then
5601 elsif Try_By_Protected_Procedure_Prefixed_View
then
5604 -- If the prefix type is the actual for a formal derived type,
5605 -- or a derived type thereof, the component inherited from the
5606 -- generic parent may not be visible in the actual, but the
5607 -- selected component is legal. This case must be handled before
5608 -- trying the object.operation notation to avoid reporting
5609 -- spurious errors, but must be skipped when Is_Prefixed_Call has
5610 -- been set (because that means that this node was resolved to an
5611 -- Object.Operation call when the generic unit was analyzed).
5614 and then not Is_Prefixed_Call
(N
)
5615 and then Is_Tagged_Type
(Prefix_Type
)
5616 and then Try_Selected_Component_In_Instance
(Type_To_Use
)
5620 elsif Try_Object_Operation
(N
) then
5624 -- If the transformation fails, it will be necessary to redo the
5625 -- analysis with all errors enabled, to indicate candidate
5626 -- interpretations and reasons for each failure ???
5630 elsif Is_Private_Type
(Prefix_Type
) then
5632 -- Allow access only to discriminants of the type. If the type has
5633 -- no full view, gigi uses the parent type for the components, so we
5634 -- do the same here.
5636 if No
(Full_View
(Prefix_Type
)) then
5637 Type_To_Use
:= Root_Type
(Base_Type
(Prefix_Type
));
5638 Comp
:= First_Entity
(Type_To_Use
);
5641 while Present
(Comp
) loop
5642 if Chars
(Comp
) = Chars
(Sel
) then
5643 if Ekind
(Comp
) = E_Discriminant
then
5644 Set_Entity_With_Checks
(Sel
, Comp
);
5645 Generate_Reference
(Comp
, Sel
);
5647 Set_Etype
(Sel
, Etype
(Comp
));
5648 Set_Etype
(N
, Etype
(Comp
));
5649 Check_Implicit_Dereference
(N
, Etype
(N
));
5651 if Is_Generic_Type
(Prefix_Type
)
5652 or else Is_Generic_Type
(Root_Type
(Prefix_Type
))
5654 Set_Original_Discriminant
(Sel
, Comp
);
5657 -- Before declaring an error, check whether this is tagged
5658 -- private type and a call to a primitive operation.
5660 elsif Ada_Version
>= Ada_2005
5661 and then Is_Tagged_Type
(Prefix_Type
)
5662 and then Try_Object_Operation
(N
)
5667 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
5668 Error_Msg_NE
("invisible selector& for }", N
, Sel
);
5669 Set_Entity
(Sel
, Any_Id
);
5670 Set_Etype
(N
, Any_Type
);
5679 -- Extension feature: Also support calls with prefixed views for
5680 -- untagged private types.
5682 if Core_Extensions_Allowed
then
5683 if Try_Object_Operation
(N
) then
5688 elsif Is_Concurrent_Type
(Prefix_Type
) then
5690 -- Find visible operation with given name. For a protected type,
5691 -- the possible candidates are discriminants, entries or protected
5692 -- subprograms. For a task type, the set can only include entries or
5693 -- discriminants if the task type is not an enclosing scope. If it
5694 -- is an enclosing scope (e.g. in an inner task) then all entities
5695 -- are visible, but the prefix must denote the enclosing scope, i.e.
5696 -- can only be a direct name or an expanded name.
5698 Set_Etype
(Sel
, Any_Type
);
5699 Hidden_Comp
:= Empty
;
5700 In_Scope
:= In_Open_Scopes
(Prefix_Type
);
5701 Is_Private_Op
:= False;
5703 while Present
(Comp
) loop
5705 -- Do not examine private operations of the type if not within
5708 if Chars
(Comp
) = Chars
(Sel
) then
5709 if Is_Overloadable
(Comp
)
5711 or else Comp
/= First_Private_Entity
(Type_To_Use
))
5713 Add_One_Interp
(Sel
, Comp
, Etype
(Comp
));
5714 if Comp
= First_Private_Entity
(Type_To_Use
) then
5715 Is_Private_Op
:= True;
5718 -- If the prefix is tagged, the correct interpretation may
5719 -- lie in the primitive or class-wide operations of the
5720 -- type. Perform a simple conformance check to determine
5721 -- whether Try_Object_Operation should be invoked even if
5722 -- a visible entity is found.
5724 if Is_Tagged_Type
(Prefix_Type
)
5725 and then Nkind
(Parent
(N
)) in N_Function_Call
5726 | N_Indexed_Component
5727 | N_Procedure_Call_Statement
5728 and then Has_Mode_Conformant_Spec
(Comp
)
5730 Has_Candidate
:= True;
5733 -- Note: a selected component may not denote a component of a
5734 -- protected type (4.1.3(7)).
5736 elsif Ekind
(Comp
) in E_Discriminant | E_Entry_Family
5738 and then not Is_Protected_Type
(Prefix_Type
)
5739 and then Is_Entity_Name
(Name
))
5741 Set_Entity_With_Checks
(Sel
, Comp
);
5742 Generate_Reference
(Comp
, Sel
);
5744 -- The selector is not overloadable, so we have a candidate
5747 Has_Candidate
:= True;
5750 if Ekind
(Comp
) = E_Component
then
5751 Hidden_Comp
:= Comp
;
5757 Set_Etype
(Sel
, Etype
(Comp
));
5758 Set_Etype
(N
, Etype
(Comp
));
5760 if Ekind
(Comp
) = E_Discriminant
then
5761 Set_Original_Discriminant
(Sel
, Comp
);
5766 if Comp
= First_Private_Entity
(Type_To_Use
) then
5767 if Etype
(Sel
) /= Any_Type
then
5769 -- If the first private entity's name matches, then treat
5770 -- it as a private op: needed for the error check for
5771 -- illegal selection of private entities further below.
5773 if Chars
(Comp
) = Chars
(Sel
) then
5774 Is_Private_Op
:= True;
5777 -- We have a candidate, so exit the loop
5782 -- Indicate that subsequent operations are private,
5783 -- for better error reporting.
5785 Is_Private_Op
:= True;
5789 -- Do not examine private operations if not within scope of
5790 -- the synchronized type.
5792 exit when not In_Scope
5794 Comp
= First_Private_Entity
(Base_Type
(Prefix_Type
));
5798 -- If the scope is a current instance, the prefix cannot be an
5799 -- expression of the same type, unless the selector designates a
5800 -- public operation (otherwise that would represent an attempt to
5801 -- reach an internal entity of another synchronized object).
5803 -- This is legal if prefix is an access to such type and there is
5804 -- a dereference, or is a component with a dereferenced prefix.
5805 -- It is also legal if the prefix is a component of a task type,
5806 -- and the selector is one of the task operations.
5809 and then not Is_Entity_Name
(Name
)
5810 and then not Has_Dereference
(Name
)
5812 if Is_Task_Type
(Prefix_Type
)
5813 and then Present
(Entity
(Sel
))
5814 and then Is_Entry
(Entity
(Sel
))
5818 elsif Is_Protected_Type
(Prefix_Type
)
5819 and then Is_Overloadable
(Entity
(Sel
))
5820 and then not Is_Private_Op
5826 ("invalid reference to internal operation of some object of "
5827 & "type &", N
, Type_To_Use
);
5828 Set_Entity
(Sel
, Any_Id
);
5829 Set_Etype
(Sel
, Any_Type
);
5833 -- Another special case: the prefix may denote an object of the type
5834 -- (but not a type) in which case this is an external call and the
5835 -- operation must be public.
5838 and then Is_Object_Reference
(Original_Node
(Prefix
(N
)))
5839 and then Comes_From_Source
(N
)
5840 and then Is_Private_Op
5842 if Present
(Hidden_Comp
) then
5844 ("invalid reference to private component of object of type "
5845 & "&", N
, Type_To_Use
);
5849 ("invalid reference to private operation of some object of "
5850 & "type &", N
, Type_To_Use
);
5853 Set_Entity
(Sel
, Any_Id
);
5854 Set_Etype
(Sel
, Any_Type
);
5858 -- If there is no visible entity with the given name or none of the
5859 -- visible entities are plausible interpretations, check whether
5860 -- there is some other primitive operation with that name.
5862 if Ada_Version
>= Ada_2005
and then Is_Tagged_Type
(Prefix_Type
) then
5863 if (Etype
(N
) = Any_Type
5864 or else not Has_Candidate
)
5865 and then Try_Object_Operation
(N
)
5869 -- If the context is not syntactically a procedure call, it
5870 -- may be a call to a primitive function declared outside of
5871 -- the synchronized type.
5873 -- If the context is a procedure call, there might still be
5874 -- an overloading between an entry and a primitive procedure
5875 -- declared outside of the synchronized type, called in prefix
5876 -- notation. This is harder to disambiguate because in one case
5877 -- the controlling formal is implicit ???
5879 elsif Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
5880 and then Nkind
(Parent
(N
)) /= N_Indexed_Component
5881 and then Try_Object_Operation
(N
)
5886 -- Ada 2012 (AI05-0090-1): If we found a candidate of a call to an
5887 -- entry or procedure of a tagged concurrent type we must check
5888 -- if there are class-wide subprograms covering the primitive. If
5889 -- true then Try_Object_Operation reports the error.
5892 and then Is_Concurrent_Type
(Prefix_Type
)
5893 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
5895 -- Duplicate the call. This is required to avoid problems with
5896 -- the tree transformations performed by Try_Object_Operation.
5897 -- Set properly the parent of the copied call, because it is
5898 -- about to be reanalyzed.
5901 Par
: constant Node_Id
:= New_Copy_Tree
(Parent
(N
));
5904 Set_Parent
(Par
, Parent
(Parent
(N
)));
5906 if Try_Object_Operation
5907 (Sinfo
.Nodes
.Name
(Par
), CW_Test_Only
=> True)
5915 if Etype
(N
) = Any_Type
and then Is_Protected_Type
(Prefix_Type
) then
5917 -- Case of a prefix of a protected type: selector might denote
5918 -- an invisible private component.
5920 Comp
:= First_Private_Entity
(Base_Type
(Prefix_Type
));
5921 while Present
(Comp
) and then Chars
(Comp
) /= Chars
(Sel
) loop
5925 if Present
(Comp
) then
5926 if Is_Single_Concurrent_Object
then
5927 Error_Msg_Node_2
:= Entity
(Name
);
5928 Error_Msg_NE
("invisible selector& for &", N
, Sel
);
5931 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
5932 Error_Msg_NE
("invisible selector& for }", N
, Sel
);
5938 Set_Is_Overloaded
(N
, Is_Overloaded
(Sel
));
5940 -- Extension feature: Also support calls with prefixed views for
5943 elsif Core_Extensions_Allowed
5944 and then Try_Object_Operation
(N
)
5951 Error_Msg_NE
("invalid prefix in selected component&", N
, Sel
);
5954 -- If N still has no type, the component is not defined in the prefix
5956 if Etype
(N
) = Any_Type
then
5958 if Is_Single_Concurrent_Object
then
5959 Error_Msg_Node_2
:= Entity
(Name
);
5960 Error_Msg_NE
("no selector& for&", N
, Sel
);
5962 Check_Misspelled_Selector
(Type_To_Use
, Sel
);
5964 -- If this is a derived formal type, the parent may have different
5965 -- visibility at this point. Try for an inherited component before
5966 -- reporting an error.
5968 elsif Is_Generic_Type
(Prefix_Type
)
5969 and then Ekind
(Prefix_Type
) = E_Record_Type_With_Private
5970 and then Prefix_Type
/= Etype
(Prefix_Type
)
5971 and then Is_Record_Type
(Etype
(Prefix_Type
))
5973 Set_Etype
(Prefix
(N
), Etype
(Prefix_Type
));
5974 Analyze_Selected_Component
(N
);
5977 -- Similarly, if this is the actual for a formal derived type, or
5978 -- a derived type thereof, the component inherited from the generic
5979 -- parent may not be visible in the actual, but the selected
5980 -- component is legal.
5982 elsif In_Instance
and then Is_Tagged_Type
(Prefix_Type
) then
5984 -- Climb up the derivation chain of the generic parent type until
5985 -- we find the proper ancestor type.
5987 if Try_Selected_Component_In_Instance
(Type_To_Use
) then
5990 -- The search above must have eventually succeeded, since the
5991 -- selected component was legal in the generic.
5994 raise Program_Error
;
5997 -- Component not found, specialize error message when appropriate
6000 if Ekind
(Prefix_Type
) = E_Record_Subtype
then
6002 -- Check whether this is a component of the base type which
6003 -- is absent from a statically constrained subtype. This will
6004 -- raise constraint error at run time, but is not a compile-
6005 -- time error. When the selector is illegal for base type as
6006 -- well fall through and generate a compilation error anyway.
6008 Comp
:= First_Component
(Base_Type
(Prefix_Type
));
6009 while Present
(Comp
) loop
6010 if Chars
(Comp
) = Chars
(Sel
)
6011 and then Is_Visible_Component
(Comp
, Sel
)
6013 Set_Entity_With_Checks
(Sel
, Comp
);
6014 Generate_Reference
(Comp
, Sel
);
6015 Set_Etype
(Sel
, Etype
(Comp
));
6016 Set_Etype
(N
, Etype
(Comp
));
6018 -- Emit appropriate message. The node will be replaced
6019 -- by an appropriate raise statement.
6021 -- Note that in SPARK mode, as with all calls to apply a
6022 -- compile time constraint error, this will be made into
6023 -- an error to simplify the processing of the formal
6024 -- verification backend.
6026 Apply_Compile_Time_Constraint_Error
6027 (N
, "component not present in }??",
6028 CE_Discriminant_Check_Failed
,
6031 SPARK_Mode
= On
or not In_Instance_Not_Visible
);
6035 Next_Component
(Comp
);
6040 Error_Msg_Node_2
:= First_Subtype
(Prefix_Type
);
6041 Error_Msg_NE
("no selector& for}", N
, Sel
);
6043 -- Add information in the case of an incomplete prefix
6045 if Is_Incomplete_Type
(Type_To_Use
) then
6047 Inc
: constant Entity_Id
:= First_Subtype
(Type_To_Use
);
6050 if From_Limited_With
(Scope
(Type_To_Use
)) then
6052 ("\limited view of& has no components", N
, Inc
);
6056 ("\premature usage of incomplete type&", N
, Inc
);
6058 if Nkind
(Parent
(Inc
)) =
6059 N_Incomplete_Type_Declaration
6061 -- Record location of premature use in entity so that
6062 -- a continuation message is generated when the
6063 -- completion is seen.
6065 Set_Premature_Use
(Parent
(Inc
), N
);
6071 Check_Misspelled_Selector
(Type_To_Use
, Sel
);
6074 Set_Entity
(Sel
, Any_Id
);
6075 Set_Etype
(Sel
, Any_Type
);
6077 end Analyze_Selected_Component
;
6079 ---------------------------
6080 -- Analyze_Short_Circuit --
6081 ---------------------------
6083 procedure Analyze_Short_Circuit
(N
: Node_Id
) is
6084 L
: constant Node_Id
:= Left_Opnd
(N
);
6085 R
: constant Node_Id
:= Right_Opnd
(N
);
6090 Set_Etype
(N
, Any_Type
);
6091 Analyze_Expression
(L
);
6092 Analyze_Expression
(R
);
6094 if not Is_Overloaded
(L
) then
6095 if Root_Type
(Etype
(L
)) = Standard_Boolean
6096 and then Has_Compatible_Type
(R
, Etype
(L
))
6098 Add_One_Interp
(N
, Etype
(L
), Etype
(L
));
6102 Get_First_Interp
(L
, Ind
, It
);
6103 while Present
(It
.Typ
) loop
6104 if Root_Type
(It
.Typ
) = Standard_Boolean
6105 and then Has_Compatible_Type
(R
, It
.Typ
)
6107 Add_One_Interp
(N
, It
.Typ
, It
.Typ
);
6110 Get_Next_Interp
(Ind
, It
);
6114 -- Here we have failed to find an interpretation. Clearly we know that
6115 -- it is not the case that both operands can have an interpretation of
6116 -- Boolean, but this is by far the most likely intended interpretation.
6117 -- So we simply resolve both operands as Booleans, and at least one of
6118 -- these resolutions will generate an error message, and we do not need
6119 -- to give another error message on the short circuit operation itself.
6121 if Etype
(N
) = Any_Type
then
6122 Resolve
(L
, Standard_Boolean
);
6123 Resolve
(R
, Standard_Boolean
);
6124 Set_Etype
(N
, Standard_Boolean
);
6128 if Nkind
(L
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
6130 Check_Xtra_Parens_Precedence
(L
);
6133 if Nkind
(R
) not in N_Short_Circuit | N_Op_And | N_Op_Or | N_Op_Xor
6135 Check_Xtra_Parens_Precedence
(R
);
6138 end Analyze_Short_Circuit
;
6144 procedure Analyze_Slice
(N
: Node_Id
) is
6145 D
: constant Node_Id
:= Discrete_Range
(N
);
6146 P
: constant Node_Id
:= Prefix
(N
);
6147 Array_Type
: Entity_Id
;
6148 Index_Type
: Entity_Id
;
6150 procedure Analyze_Overloaded_Slice
;
6151 -- If the prefix is overloaded, select those interpretations that
6152 -- yield a one-dimensional array type.
6154 ------------------------------
6155 -- Analyze_Overloaded_Slice --
6156 ------------------------------
6158 procedure Analyze_Overloaded_Slice
is
6164 Set_Etype
(N
, Any_Type
);
6166 Get_First_Interp
(P
, I
, It
);
6167 while Present
(It
.Nam
) loop
6170 if Is_Access_Type
(Typ
) then
6171 Typ
:= Designated_Type
(Typ
);
6173 (Warn_On_Dereference
, "?d?implicit dereference", N
);
6176 if Is_Array_Type
(Typ
)
6177 and then Number_Dimensions
(Typ
) = 1
6178 and then Has_Compatible_Type
(D
, Etype
(First_Index
(Typ
)))
6180 Add_One_Interp
(N
, Typ
, Typ
);
6183 Get_Next_Interp
(I
, It
);
6186 if Etype
(N
) = Any_Type
then
6187 Error_Msg_N
("expect array type in prefix of slice", N
);
6189 end Analyze_Overloaded_Slice
;
6191 -- Start of processing for Analyze_Slice
6197 if Is_Overloaded
(P
) then
6198 Analyze_Overloaded_Slice
;
6201 Array_Type
:= Etype
(P
);
6202 Set_Etype
(N
, Any_Type
);
6204 if Is_Access_Type
(Array_Type
) then
6205 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
6206 Array_Type
:= Implicitly_Designated_Type
(Array_Type
);
6209 if not Is_Array_Type
(Array_Type
) then
6210 Wrong_Type
(P
, Any_Array
);
6212 elsif Number_Dimensions
(Array_Type
) > 1 then
6214 ("type is not one-dimensional array in slice prefix", N
);
6217 if Ekind
(Array_Type
) = E_String_Literal_Subtype
then
6218 Index_Type
:= Etype
(String_Literal_Low_Bound
(Array_Type
));
6220 Index_Type
:= Etype
(First_Index
(Array_Type
));
6223 if not Has_Compatible_Type
(D
, Index_Type
) then
6224 Wrong_Type
(D
, Index_Type
);
6226 Set_Etype
(N
, Array_Type
);
6232 -----------------------------
6233 -- Analyze_Type_Conversion --
6234 -----------------------------
6236 procedure Analyze_Type_Conversion
(N
: Node_Id
) is
6237 Expr
: constant Node_Id
:= Expression
(N
);
6238 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
6243 -- If Conversion_OK is set, then the Etype is already set, and the only
6244 -- processing required is to analyze the expression. This is used to
6245 -- construct certain "illegal" conversions which are not allowed by Ada
6246 -- semantics, but can be handled by Gigi, see Sinfo for further details.
6248 if Conversion_OK
(N
) then
6253 -- Otherwise full type analysis is required, as well as some semantic
6254 -- checks to make sure the argument of the conversion is appropriate.
6257 Typ
:= Entity
(Mark
);
6260 Analyze_Expression
(Expr
);
6262 Check_Fully_Declared
(Typ
, N
);
6263 Validate_Remote_Type_Type_Conversion
(N
);
6265 -- Only remaining step is validity checks on the argument. These
6266 -- are skipped if the conversion does not come from the source.
6268 if not Comes_From_Source
(N
) then
6271 -- If there was an error in a generic unit, no need to replicate the
6272 -- error message. Conversely, constant-folding in the generic may
6273 -- transform the argument of a conversion into a string literal, which
6274 -- is legal. Therefore the following tests are not performed in an
6275 -- instance. The same applies to an inlined body.
6277 elsif In_Instance
or In_Inlined_Body
then
6280 elsif Nkind
(Expr
) = N_Null
then
6281 Error_Msg_N
("argument of conversion cannot be null", N
);
6282 Error_Msg_N
("\use qualified expression instead", N
);
6283 Set_Etype
(N
, Any_Type
);
6285 elsif Nkind
(Expr
) = N_Aggregate
then
6286 Error_Msg_N
("argument of conversion cannot be aggregate", N
);
6287 Error_Msg_N
("\use qualified expression instead", N
);
6289 elsif Nkind
(Expr
) = N_Allocator
then
6290 Error_Msg_N
("argument of conversion cannot be allocator", N
);
6291 Error_Msg_N
("\use qualified expression instead", N
);
6293 elsif Nkind
(Expr
) = N_String_Literal
then
6294 Error_Msg_N
("argument of conversion cannot be string literal", N
);
6295 Error_Msg_N
("\use qualified expression instead", N
);
6297 elsif Nkind
(Expr
) = N_Character_Literal
then
6298 if Ada_Version
= Ada_83
then
6299 Resolve
(Expr
, Typ
);
6302 ("argument of conversion cannot be character literal", N
);
6303 Error_Msg_N
("\use qualified expression instead", N
);
6306 elsif Nkind
(Expr
) = N_Attribute_Reference
6307 and then Attribute_Name
(Expr
) in Name_Access
6308 | Name_Unchecked_Access
6309 | Name_Unrestricted_Access
6312 ("argument of conversion cannot be access attribute", N
);
6313 Error_Msg_N
("\use qualified expression instead", N
);
6316 -- A formal parameter of a specific tagged type whose related subprogram
6317 -- is subject to pragma Extensions_Visible with value "False" cannot
6318 -- appear in a class-wide conversion (SPARK RM 6.1.7(3)). Do not check
6319 -- internally generated expressions.
6321 if Is_Class_Wide_Type
(Typ
)
6322 and then Comes_From_Source
(Expr
)
6323 and then Is_EVF_Expression
(Expr
)
6326 ("formal parameter cannot be converted to class-wide type when "
6327 & "Extensions_Visible is False", Expr
);
6329 end Analyze_Type_Conversion
;
6331 ----------------------
6332 -- Analyze_Unary_Op --
6333 ----------------------
6335 procedure Analyze_Unary_Op
(N
: Node_Id
) is
6336 R
: constant Node_Id
:= Right_Opnd
(N
);
6341 Set_Etype
(N
, Any_Type
);
6342 Candidate_Type
:= Empty
;
6344 Analyze_Expression
(R
);
6346 -- If the entity is already set, the node is the instantiation of a
6347 -- generic node with a non-local reference, or was manufactured by a
6348 -- call to Make_Op_xxx. In either case the entity is known to be valid,
6349 -- and we do not need to collect interpretations, instead we just get
6350 -- the single possible interpretation.
6352 if Present
(Entity
(N
)) then
6353 Op_Id
:= Entity
(N
);
6355 if Ekind
(Op_Id
) = E_Operator
then
6356 Find_Unary_Types
(R
, Op_Id
, N
);
6358 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
6362 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
6363 while Present
(Op_Id
) loop
6364 if Ekind
(Op_Id
) = E_Operator
then
6365 if No
(Next_Entity
(First_Entity
(Op_Id
))) then
6366 Find_Unary_Types
(R
, Op_Id
, N
);
6369 elsif Is_Overloadable
(Op_Id
) then
6370 Analyze_User_Defined_Unary_Op
(N
, Op_Id
);
6373 Op_Id
:= Homonym
(Op_Id
);
6378 end Analyze_Unary_Op
;
6380 ----------------------------------
6381 -- Analyze_Unchecked_Expression --
6382 ----------------------------------
6384 procedure Analyze_Unchecked_Expression
(N
: Node_Id
) is
6385 Expr
: constant Node_Id
:= Expression
(N
);
6388 Analyze
(Expr
, Suppress
=> All_Checks
);
6389 Set_Etype
(N
, Etype
(Expr
));
6390 Save_Interps
(Expr
, N
);
6391 end Analyze_Unchecked_Expression
;
6393 ---------------------------------------
6394 -- Analyze_Unchecked_Type_Conversion --
6395 ---------------------------------------
6397 procedure Analyze_Unchecked_Type_Conversion
(N
: Node_Id
) is
6398 Expr
: constant Node_Id
:= Expression
(N
);
6399 Mark
: constant Entity_Id
:= Subtype_Mark
(N
);
6403 Set_Etype
(N
, Entity
(Mark
));
6404 Analyze_Expression
(Expr
);
6405 end Analyze_Unchecked_Type_Conversion
;
6407 ------------------------------------
6408 -- Analyze_User_Defined_Binary_Op --
6409 ------------------------------------
6411 procedure Analyze_User_Defined_Binary_Op
6413 Op_Id
: Entity_Id
) is
6416 F1
: constant Entity_Id
:= First_Formal
(Op_Id
);
6417 F2
: constant Entity_Id
:= Next_Formal
(F1
);
6420 -- Verify that Op_Id is a visible binary function. Note that since
6421 -- we know Op_Id is overloaded, potentially use visible means use
6422 -- visible for sure (RM 9.4(11)). Be prepared for previous errors.
6424 if Ekind
(Op_Id
) = E_Function
6425 and then Present
(F2
)
6426 and then (Is_Immediately_Visible
(Op_Id
)
6427 or else Is_Potentially_Use_Visible
(Op_Id
))
6428 and then (Has_Compatible_Type
(Left_Opnd
(N
), Etype
(F1
))
6429 or else Etype
(F1
) = Any_Type
)
6430 and then (Has_Compatible_Type
(Right_Opnd
(N
), Etype
(F2
))
6431 or else Etype
(F2
) = Any_Type
)
6433 Add_One_Interp
(N
, Op_Id
, Base_Type
(Etype
(Op_Id
)));
6435 -- If the operands are overloaded, indicate that the current
6436 -- type is a viable candidate. This is redundant in most cases,
6437 -- but for equality and comparison operators where the context
6438 -- does not impose a type on the operands, setting the proper
6439 -- type is necessary to avoid subsequent ambiguities during
6440 -- resolution, when both user-defined and predefined operators
6441 -- may be candidates.
6443 if Is_Overloaded
(Left_Opnd
(N
)) then
6444 Set_Etype
(Left_Opnd
(N
), Etype
(F1
));
6447 if Is_Overloaded
(Right_Opnd
(N
)) then
6448 Set_Etype
(Right_Opnd
(N
), Etype
(F2
));
6451 if Debug_Flag_E
then
6452 Write_Str
("user defined operator ");
6453 Write_Name
(Chars
(Op_Id
));
6454 Write_Str
(" on node ");
6455 Write_Int
(Int
(N
));
6460 end Analyze_User_Defined_Binary_Op
;
6462 -----------------------------------
6463 -- Analyze_User_Defined_Unary_Op --
6464 -----------------------------------
6466 procedure Analyze_User_Defined_Unary_Op
6471 -- Only do analysis if the operator Comes_From_Source, since otherwise
6472 -- the operator was generated by the expander, and all such operators
6473 -- always refer to the operators in package Standard.
6475 if Comes_From_Source
(N
) then
6477 F
: constant Entity_Id
:= First_Formal
(Op_Id
);
6480 -- Verify that Op_Id is a visible unary function. Note that since
6481 -- we know Op_Id is overloaded, potentially use visible means use
6482 -- visible for sure (RM 9.4(11)).
6484 if Ekind
(Op_Id
) = E_Function
6485 and then No
(Next_Formal
(F
))
6486 and then (Is_Immediately_Visible
(Op_Id
)
6487 or else Is_Potentially_Use_Visible
(Op_Id
))
6488 and then Has_Compatible_Type
(Right_Opnd
(N
), Etype
(F
))
6490 Add_One_Interp
(N
, Op_Id
, Etype
(Op_Id
));
6494 end Analyze_User_Defined_Unary_Op
;
6496 ---------------------------
6497 -- Check_Arithmetic_Pair --
6498 ---------------------------
6500 procedure Check_Arithmetic_Pair
6501 (T1
, T2
: Entity_Id
;
6505 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
6507 function Has_Fixed_Op
(Typ
: Entity_Id
; Op
: Entity_Id
) return Boolean;
6508 -- Check whether the fixed-point type Typ has a user-defined operator
6509 -- (multiplication or division) that should hide the corresponding
6510 -- predefined operator. Used to implement Ada 2005 AI-264, to make
6511 -- such operators more visible and therefore useful.
6513 -- If the name of the operation is an expanded name with prefix
6514 -- Standard, the predefined universal fixed operator is available,
6515 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
6521 function Has_Fixed_Op
(Typ
: Entity_Id
; Op
: Entity_Id
) return Boolean is
6522 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
6528 -- If the universal_fixed operation is given explicitly the rule
6529 -- concerning primitive operations of the type do not apply.
6531 if Nkind
(N
) = N_Function_Call
6532 and then Nkind
(Name
(N
)) = N_Expanded_Name
6533 and then Entity
(Prefix
(Name
(N
))) = Standard_Standard
6538 -- The operation is treated as primitive if it is declared in the
6539 -- same scope as the type, and therefore on the same entity chain.
6541 Ent
:= Next_Entity
(Typ
);
6542 while Present
(Ent
) loop
6543 if Chars
(Ent
) = Chars
(Op
) then
6544 F1
:= First_Formal
(Ent
);
6545 F2
:= Next_Formal
(F1
);
6547 -- The operation counts as primitive if either operand or
6548 -- result are of the given base type, and both operands are
6549 -- fixed point types.
6551 if (Base_Type
(Etype
(F1
)) = Bas
6552 and then Is_Fixed_Point_Type
(Etype
(F2
)))
6555 (Base_Type
(Etype
(F2
)) = Bas
6556 and then Is_Fixed_Point_Type
(Etype
(F1
)))
6559 (Base_Type
(Etype
(Ent
)) = Bas
6560 and then Is_Fixed_Point_Type
(Etype
(F1
))
6561 and then Is_Fixed_Point_Type
(Etype
(F2
)))
6573 -- Start of processing for Check_Arithmetic_Pair
6576 if Op_Name
in Name_Op_Add | Name_Op_Subtract
then
6577 if Is_Numeric_Type
(T1
)
6578 and then Is_Numeric_Type
(T2
)
6579 and then (Covers
(T1
=> T1
, T2
=> T2
)
6581 Covers
(T1
=> T2
, T2
=> T1
))
6583 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6586 elsif Op_Name
in Name_Op_Multiply | Name_Op_Divide
then
6587 if Is_Fixed_Point_Type
(T1
)
6588 and then (Is_Fixed_Point_Type
(T2
) or else T2
= Universal_Real
)
6590 -- Add one interpretation with universal fixed result
6592 if not Has_Fixed_Op
(T1
, Op_Id
)
6593 or else Nkind
(Parent
(N
)) = N_Type_Conversion
6595 Add_One_Interp
(N
, Op_Id
, Universal_Fixed
);
6598 elsif Is_Fixed_Point_Type
(T2
)
6599 and then T1
= Universal_Real
6601 (not Has_Fixed_Op
(T1
, Op_Id
)
6602 or else Nkind
(Parent
(N
)) = N_Type_Conversion
)
6604 Add_One_Interp
(N
, Op_Id
, Universal_Fixed
);
6606 elsif Is_Numeric_Type
(T1
)
6607 and then Is_Numeric_Type
(T2
)
6608 and then (Covers
(T1
=> T1
, T2
=> T2
)
6610 Covers
(T1
=> T2
, T2
=> T1
))
6612 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6614 elsif Is_Fixed_Point_Type
(T1
)
6615 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6616 or else T2
= Universal_Integer
)
6618 Add_One_Interp
(N
, Op_Id
, T1
);
6620 elsif T2
= Universal_Real
6621 and then Base_Type
(T1
) = Base_Type
(Standard_Integer
)
6622 and then Op_Name
= Name_Op_Multiply
6624 Add_One_Interp
(N
, Op_Id
, Any_Fixed
);
6626 elsif T1
= Universal_Real
6627 and then Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6629 Add_One_Interp
(N
, Op_Id
, Any_Fixed
);
6631 elsif Is_Fixed_Point_Type
(T2
)
6632 and then (Base_Type
(T1
) = Base_Type
(Standard_Integer
)
6633 or else T1
= Universal_Integer
)
6634 and then Op_Name
= Name_Op_Multiply
6636 Add_One_Interp
(N
, Op_Id
, T2
);
6638 elsif T1
= Universal_Real
and then T2
= Universal_Integer
then
6639 Add_One_Interp
(N
, Op_Id
, T1
);
6641 elsif T2
= Universal_Real
6642 and then T1
= Universal_Integer
6643 and then Op_Name
= Name_Op_Multiply
6645 Add_One_Interp
(N
, Op_Id
, T2
);
6648 elsif Op_Name
= Name_Op_Mod
or else Op_Name
= Name_Op_Rem
then
6650 if Is_Integer_Type
(T1
)
6651 and then (Covers
(T1
=> T1
, T2
=> T2
)
6653 Covers
(T1
=> T2
, T2
=> T1
))
6655 Add_One_Interp
(N
, Op_Id
, Specific_Type
(T1
, T2
));
6658 elsif Op_Name
= Name_Op_Expon
then
6659 if Is_Numeric_Type
(T1
)
6660 and then not Is_Fixed_Point_Type
(T1
)
6661 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6662 or else T2
= Universal_Integer
)
6664 Add_One_Interp
(N
, Op_Id
, Base_Type
(T1
));
6667 else pragma Assert
(Nkind
(N
) in N_Op_Shift
);
6669 -- If not one of the predefined operators, the node may be one
6670 -- of the intrinsic functions. Its kind is always specific, and
6671 -- we can use it directly, rather than the name of the operation.
6673 if Is_Integer_Type
(T1
)
6674 and then (Base_Type
(T2
) = Base_Type
(Standard_Integer
)
6675 or else T2
= Universal_Integer
)
6677 Add_One_Interp
(N
, Op_Id
, Base_Type
(T1
));
6680 end Check_Arithmetic_Pair
;
6682 -------------------------------
6683 -- Check_Misspelled_Selector --
6684 -------------------------------
6686 procedure Check_Misspelled_Selector
6687 (Prefix
: Entity_Id
;
6690 Max_Suggestions
: constant := 2;
6691 Nr_Of_Suggestions
: Natural := 0;
6693 Suggestion_1
: Entity_Id
:= Empty
;
6694 Suggestion_2
: Entity_Id
:= Empty
;
6699 -- All the components of the prefix of selector Sel are matched against
6700 -- Sel and a count is maintained of possible misspellings. When at
6701 -- the end of the analysis there are one or two (not more) possible
6702 -- misspellings, these misspellings will be suggested as possible
6705 if not (Is_Private_Type
(Prefix
) or else Is_Record_Type
(Prefix
)) then
6707 -- Concurrent types should be handled as well ???
6712 Comp
:= First_Entity
(Prefix
);
6713 while Nr_Of_Suggestions
<= Max_Suggestions
and then Present
(Comp
) loop
6714 if Is_Visible_Component
(Comp
, Sel
) then
6715 if Is_Bad_Spelling_Of
(Chars
(Comp
), Chars
(Sel
)) then
6716 Nr_Of_Suggestions
:= Nr_Of_Suggestions
+ 1;
6718 case Nr_Of_Suggestions
is
6719 when 1 => Suggestion_1
:= Comp
;
6720 when 2 => Suggestion_2
:= Comp
;
6721 when others => null;
6729 -- Report at most two suggestions
6731 if Nr_Of_Suggestions
= 1 then
6732 Error_Msg_NE
-- CODEFIX
6733 ("\possible misspelling of&", Sel
, Suggestion_1
);
6735 elsif Nr_Of_Suggestions
= 2 then
6736 Error_Msg_Node_2
:= Suggestion_2
;
6737 Error_Msg_NE
-- CODEFIX
6738 ("\possible misspelling of& or&", Sel
, Suggestion_1
);
6740 end Check_Misspelled_Selector
;
6746 procedure Diagnose_Call
(N
: Node_Id
; Nam
: Node_Id
) is
6752 Num_Actuals
: Natural;
6753 Num_Interps
: Natural;
6754 Void_Interp_Seen
: Boolean := False;
6757 pragma Warnings
(Off
, Boolean);
6761 Actual
:= First_Actual
(N
);
6763 while Present
(Actual
) loop
6764 -- Ada 2005 (AI-50217): Post an error in case of premature
6765 -- usage of an entity from the limited view.
6767 if not Analyzed
(Etype
(Actual
))
6768 and then From_Limited_With
(Etype
(Actual
))
6769 and then Ada_Version
>= Ada_2005
6771 Error_Msg_Qual_Level
:= 1;
6773 ("missing with_clause for scope of imported type&",
6774 Actual
, Etype
(Actual
));
6775 Error_Msg_Qual_Level
:= 0;
6778 Num_Actuals
:= Num_Actuals
+ 1;
6779 Next_Actual
(Actual
);
6782 -- Before listing the possible candidates, check whether this is
6783 -- a prefix of a selected component that has been rewritten as a
6784 -- parameterless function call because there is a callable candidate
6785 -- interpretation. If there is a hidden package in the list of homonyms
6786 -- of the function name (bad programming style in any case) suggest that
6787 -- this is the intended entity.
6789 if No
(Parameter_Associations
(N
))
6790 and then Nkind
(Parent
(N
)) = N_Selected_Component
6791 and then Nkind
(Parent
(Parent
(N
))) in N_Declaration
6792 and then Is_Overloaded
(Nam
)
6798 Ent
:= Current_Entity
(Nam
);
6799 while Present
(Ent
) loop
6800 if Ekind
(Ent
) = E_Package
then
6802 ("no legal interpretations as function call,!", Nam
);
6803 Error_Msg_NE
("\package& is not visible", N
, Ent
);
6805 Rewrite
(Parent
(N
),
6806 New_Occurrence_Of
(Any_Type
, Sloc
(N
)));
6810 Ent
:= Homonym
(Ent
);
6815 -- If this is a call to an operation of a concurrent type, the failed
6816 -- interpretations have been removed from the name. Recover them now
6817 -- in order to provide full diagnostics.
6819 if Nkind
(Parent
(Nam
)) = N_Selected_Component
then
6820 Set_Entity
(Nam
, Empty
);
6821 New_Nam
:= New_Copy_Tree
(Parent
(Nam
));
6822 Set_Is_Overloaded
(New_Nam
, False);
6823 Set_Is_Overloaded
(Selector_Name
(New_Nam
), False);
6824 Set_Parent
(New_Nam
, Parent
(Parent
(Nam
)));
6825 Analyze_Selected_Component
(New_Nam
);
6826 Get_First_Interp
(Selector_Name
(New_Nam
), X
, It
);
6828 Get_First_Interp
(Nam
, X
, It
);
6831 -- If the number of actuals is 2, then remove interpretations involving
6832 -- a unary "+" operator as they might yield confusing errors downstream.
6835 and then Nkind
(Parent
(Nam
)) /= N_Selected_Component
6839 while Present
(It
.Nam
) loop
6840 if Ekind
(It
.Nam
) = E_Operator
6841 and then Chars
(It
.Nam
) = Name_Op_Add
6842 and then (No
(First_Formal
(It
.Nam
))
6843 or else No
(Next_Formal
(First_Formal
(It
.Nam
))))
6847 Num_Interps
:= Num_Interps
+ 1;
6850 Get_Next_Interp
(X
, It
);
6853 if Num_Interps
= 0 then
6854 Error_Msg_N
("!too many arguments in call to&", Nam
);
6858 Get_First_Interp
(Nam
, X
, It
);
6861 Num_Interps
:= 2; -- at least
6864 -- Analyze each candidate call again with full error reporting for each
6866 if Num_Interps
> 1 then
6867 Error_Msg_N
("!no candidate interpretations match the actuals:", Nam
);
6870 Err_Mode
:= All_Errors_Mode
;
6871 All_Errors_Mode
:= True;
6873 while Present
(It
.Nam
) loop
6874 if Etype
(It
.Nam
) = Standard_Void_Type
then
6875 Void_Interp_Seen
:= True;
6878 Analyze_One_Call
(N
, It
.Nam
, True, Success
);
6879 Get_Next_Interp
(X
, It
);
6882 if Nkind
(N
) = N_Function_Call
then
6883 Get_First_Interp
(Nam
, X
, It
);
6886 and then Ekind
(Entity
(Name
(N
))) = E_Function
6887 and then Present
(Homonym
(Entity
(Name
(N
))))
6889 -- A name may appear overloaded if it has a homonym, even if that
6890 -- homonym is non-overloadable, in which case the overload list is
6891 -- in fact empty. This specialized case deserves a special message
6892 -- if the homonym is a child package.
6895 Nam
: constant Node_Id
:= Name
(N
);
6896 H
: constant Entity_Id
:= Homonym
(Entity
(Nam
));
6899 if Ekind
(H
) = E_Package
and then Is_Child_Unit
(H
) then
6900 Error_Msg_Qual_Level
:= 2;
6901 Error_Msg_NE
("if an entity in package& is meant, ", Nam
, H
);
6902 Error_Msg_NE
("\use a fully qualified name", Nam
, H
);
6903 Error_Msg_Qual_Level
:= 0;
6908 while Present
(It
.Nam
) loop
6909 if Ekind
(It
.Nam
) in E_Function | E_Operator
then
6912 Get_Next_Interp
(X
, It
);
6916 -- If all interpretations are procedures, this deserves a more
6917 -- precise message. Ditto if this appears as the prefix of a
6918 -- selected component, which may be a lexical error.
6921 ("\context requires function call, found procedure name", Nam
);
6923 if Nkind
(Parent
(N
)) = N_Selected_Component
6924 and then N
= Prefix
(Parent
(N
))
6926 Error_Msg_N
-- CODEFIX
6927 ("\period should probably be semicolon", Parent
(N
));
6931 elsif Nkind
(N
) = N_Procedure_Call_Statement
6932 and then not Void_Interp_Seen
6934 Error_Msg_N
("\function name found in procedure call", Nam
);
6937 All_Errors_Mode
:= Err_Mode
;
6940 ---------------------------
6941 -- Find_Arithmetic_Types --
6942 ---------------------------
6944 procedure Find_Arithmetic_Types
6949 procedure Check_Right_Argument
(T
: Entity_Id
);
6950 -- Check right operand of operator
6952 --------------------------
6953 -- Check_Right_Argument --
6954 --------------------------
6956 procedure Check_Right_Argument
(T
: Entity_Id
) is
6961 if not Is_Overloaded
(R
) then
6962 Check_Arithmetic_Pair
(T
, Etype
(R
), Op_Id
, N
);
6965 Get_First_Interp
(R
, I
, It
);
6966 while Present
(It
.Typ
) loop
6967 Check_Arithmetic_Pair
(T
, It
.Typ
, Op_Id
, N
);
6968 Get_Next_Interp
(I
, It
);
6971 end Check_Right_Argument
;
6978 -- Start of processing for Find_Arithmetic_Types
6981 if not Is_Overloaded
(L
) then
6982 Check_Right_Argument
(Etype
(L
));
6985 Get_First_Interp
(L
, I
, It
);
6986 while Present
(It
.Typ
) loop
6987 Check_Right_Argument
(It
.Typ
);
6988 Get_Next_Interp
(I
, It
);
6991 end Find_Arithmetic_Types
;
6993 ------------------------
6994 -- Find_Boolean_Types --
6995 ------------------------
6997 procedure Find_Boolean_Types
7002 procedure Check_Boolean_Pair
(T1
, T2
: Entity_Id
);
7003 -- Check operand pair of operator
7005 procedure Check_Right_Argument
(T
: Entity_Id
);
7006 -- Check right operand of operator
7008 ------------------------
7009 -- Check_Boolean_Pair --
7010 ------------------------
7012 procedure Check_Boolean_Pair
(T1
, T2
: Entity_Id
) is
7016 if Valid_Boolean_Arg
(T1
)
7017 and then Valid_Boolean_Arg
(T2
)
7018 and then (Covers
(T1
=> T1
, T2
=> T2
)
7019 or else Covers
(T1
=> T2
, T2
=> T1
))
7021 T
:= Specific_Type
(T1
, T2
);
7023 if T
= Universal_Integer
then
7027 Add_One_Interp
(N
, Op_Id
, T
);
7029 end Check_Boolean_Pair
;
7031 --------------------------
7032 -- Check_Right_Argument --
7033 --------------------------
7035 procedure Check_Right_Argument
(T
: Entity_Id
) is
7040 -- Defend against previous error
7042 if Nkind
(R
) = N_Error
then
7045 elsif not Is_Overloaded
(R
) then
7046 Check_Boolean_Pair
(T
, Etype
(R
));
7049 Get_First_Interp
(R
, I
, It
);
7050 while Present
(It
.Typ
) loop
7051 Check_Boolean_Pair
(T
, It
.Typ
);
7052 Get_Next_Interp
(I
, It
);
7055 end Check_Right_Argument
;
7062 -- Start of processing for Find_Boolean_Types
7065 if not Is_Overloaded
(L
) then
7066 Check_Right_Argument
(Etype
(L
));
7069 Get_First_Interp
(L
, I
, It
);
7070 while Present
(It
.Typ
) loop
7071 Check_Right_Argument
(It
.Typ
);
7072 Get_Next_Interp
(I
, It
);
7075 end Find_Boolean_Types
;
7077 ------------------------------------
7078 -- Find_Comparison_Equality_Types --
7079 ------------------------------------
7081 -- The context of the operator plays no role in resolving the operands,
7082 -- so that if there is more than one interpretation of the operands that
7083 -- is compatible with the comparison or equality, then the operation is
7084 -- ambiguous, but this cannot be reported at this point because there is
7085 -- no guarantee that the operation will be resolved to this operator yet.
7087 procedure Find_Comparison_Equality_Types
7092 Op_Name
: constant Name_Id
:= Chars
(Op_Id
);
7093 Op_Typ
: Entity_Id
renames Standard_Boolean
;
7095 function Try_Left_Interp
(T
: Entity_Id
) return Entity_Id
;
7096 -- Try an interpretation of the left operand with type T. Return the
7097 -- type of the interpretation of the right operand making up a valid
7098 -- operand pair, or else Any_Type if the right operand is ambiguous,
7099 -- otherwise Empty if no such pair exists.
7101 function Is_Valid_Comparison_Type
(T
: Entity_Id
) return Boolean;
7102 -- Return true if T is a valid comparison type
7104 function Is_Valid_Equality_Type
7106 Anon_Access
: Boolean) return Boolean;
7107 -- Return true if T is a valid equality type
7109 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean;
7110 -- Return true if T1 and T2 constitute a valid pair of operand types for
7111 -- L and R respectively.
7113 ---------------------
7114 -- Try_Left_Interp --
7115 ---------------------
7117 function Try_Left_Interp
(T
: Entity_Id
) return Entity_Id
is
7121 Valid_I
: Interp_Index
;
7124 -- Defend against previous error
7126 if Nkind
(R
) = N_Error
then
7129 -- Loop through the interpretations of the right operand
7131 elsif not Is_Overloaded
(R
) then
7132 if Is_Valid_Pair
(T
, Etype
(R
)) then
7140 Get_First_Interp
(R
, I
, It
);
7141 while Present
(It
.Typ
) loop
7142 if Is_Valid_Pair
(T
, It
.Typ
) then
7143 -- If several interpretations are possible, disambiguate
7146 and then Base_Type
(It
.Typ
) /= Base_Type
(R_Typ
)
7148 It
:= Disambiguate
(R
, Valid_I
, I
, Any_Type
);
7150 if It
= No_Interp
then
7162 Get_Next_Interp
(I
, It
);
7165 if Present
(R_Typ
) then
7171 end Try_Left_Interp
;
7173 ------------------------------
7174 -- Is_Valid_Comparison_Type --
7175 ------------------------------
7177 function Is_Valid_Comparison_Type
(T
: Entity_Id
) return Boolean is
7179 -- The operation must be performed in a context where the operators
7180 -- of the base type are visible.
7182 if Is_Visible_Operator
(N
, Base_Type
(T
)) then
7185 -- Save candidate type for subsequent error message, if any
7188 if Valid_Comparison_Arg
(T
) then
7189 Candidate_Type
:= T
;
7195 -- Defer to the common implementation for the rest
7197 return Valid_Comparison_Arg
(T
);
7198 end Is_Valid_Comparison_Type
;
7200 ----------------------------
7201 -- Is_Valid_Equality_Type --
7202 ----------------------------
7204 function Is_Valid_Equality_Type
7206 Anon_Access
: Boolean) return Boolean
7209 -- The operation must be performed in a context where the operators
7210 -- of the base type are visible. Deal with special types used with
7211 -- access types before type resolution is done.
7213 if Ekind
(T
) = E_Access_Attribute_Type
7214 or else (Ekind
(T
) in E_Access_Subprogram_Type
7215 | E_Access_Protected_Subprogram_Type
7217 Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
)
7218 or else Is_Visible_Operator
(N
, Base_Type
(T
))
7222 -- AI95-0230: Keep restriction imposed by Ada 83 and 95, do not allow
7223 -- anonymous access types in universal_access equality operators.
7225 elsif Anon_Access
then
7226 if Ada_Version
< Ada_2005
then
7230 -- Save candidate type for subsequent error message, if any
7233 if Valid_Equality_Arg
(T
) then
7234 Candidate_Type
:= T
;
7240 -- For the use of a "/=" operator on a tagged type, several possible
7241 -- interpretations of equality need to be considered, we don't want
7242 -- the default inequality declared in Standard to be chosen, and the
7243 -- "/=" operator will be rewritten as a negation of "=" (see the end
7244 -- of Analyze_Comparison_Equality_Op). This ensures the rewriting
7245 -- occurs during analysis rather than being delayed until expansion.
7246 -- Note that, if the node is N_Op_Ne but Op_Id is Name_Op_Eq, then we
7247 -- still proceed with the interpretation, because this indicates
7248 -- the aforementioned rewriting case where the interpretation to be
7249 -- considered is actually that of the "=" operator.
7251 if Nkind
(N
) = N_Op_Ne
7252 and then Op_Name
/= Name_Op_Eq
7253 and then Is_Tagged_Type
(T
)
7257 -- Defer to the common implementation for the rest
7260 return Valid_Equality_Arg
(T
);
7262 end Is_Valid_Equality_Type
;
7268 function Is_Valid_Pair
(T1
, T2
: Entity_Id
) return Boolean is
7270 if Op_Name
= Name_Op_Eq
or else Op_Name
= Name_Op_Ne
then
7272 Anon_Access
: constant Boolean :=
7273 Is_Anonymous_Access_Type
(T1
)
7274 or else Is_Anonymous_Access_Type
(T2
);
7275 -- RM 4.5.2(9.1/2): At least one of the operands of an equality
7276 -- operator for universal_access shall be of specific anonymous
7280 if not Is_Valid_Equality_Type
(T1
, Anon_Access
)
7281 or else not Is_Valid_Equality_Type
(T2
, Anon_Access
)
7288 if not Is_Valid_Comparison_Type
(T1
)
7289 or else not Is_Valid_Comparison_Type
(T2
)
7295 return Covers
(T1
=> T1
, T2
=> T2
)
7296 or else Covers
(T1
=> T2
, T2
=> T1
)
7297 or else Is_User_Defined_Literal
(L
, T2
)
7298 or else Is_User_Defined_Literal
(R
, T1
);
7308 Valid_I
: Interp_Index
;
7310 -- Start of processing for Find_Comparison_Equality_Types
7313 -- Loop through the interpretations of the left operand
7315 if not Is_Overloaded
(L
) then
7316 T
:= Try_Left_Interp
(Etype
(L
));
7320 Add_One_Interp
(N
, Op_Id
, Op_Typ
, Find_Unique_Type
(L
, R
));
7328 Get_First_Interp
(L
, I
, It
);
7329 while Present
(It
.Typ
) loop
7330 T
:= Try_Left_Interp
(It
.Typ
);
7333 -- If several interpretations are possible, disambiguate
7336 and then Base_Type
(It
.Typ
) /= Base_Type
(L_Typ
)
7338 It
:= Disambiguate
(L
, Valid_I
, I
, Any_Type
);
7340 if It
= No_Interp
then
7354 Get_Next_Interp
(I
, It
);
7357 if Present
(L_Typ
) then
7358 Set_Etype
(L
, L_Typ
);
7359 Set_Etype
(R
, R_Typ
);
7360 Add_One_Interp
(N
, Op_Id
, Op_Typ
, Find_Unique_Type
(L
, R
));
7363 end Find_Comparison_Equality_Types
;
7365 ------------------------------
7366 -- Find_Concatenation_Types --
7367 ------------------------------
7369 procedure Find_Concatenation_Types
7374 Is_String
: constant Boolean := Nkind
(L
) = N_String_Literal
7376 Nkind
(R
) = N_String_Literal
;
7377 Op_Type
: constant Entity_Id
:= Etype
(Op_Id
);
7380 if Is_Array_Type
(Op_Type
)
7382 -- Small but very effective optimization: if at least one operand is a
7383 -- string literal, then the type of the operator must be either array
7384 -- of characters or array of strings.
7386 and then (not Is_String
7388 Is_Character_Type
(Component_Type
(Op_Type
))
7390 Is_String_Type
(Component_Type
(Op_Type
)))
7392 and then not Is_Limited_Type
(Op_Type
)
7394 and then (Has_Compatible_Type
(L
, Op_Type
)
7396 Has_Compatible_Type
(L
, Component_Type
(Op_Type
)))
7398 and then (Has_Compatible_Type
(R
, Op_Type
)
7400 Has_Compatible_Type
(R
, Component_Type
(Op_Type
)))
7402 Add_One_Interp
(N
, Op_Id
, Op_Type
);
7404 end Find_Concatenation_Types
;
7406 -------------------------
7407 -- Find_Negation_Types --
7408 -------------------------
7410 procedure Find_Negation_Types
7415 Index
: Interp_Index
;
7419 if not Is_Overloaded
(R
) then
7420 if Etype
(R
) = Universal_Integer
then
7421 Add_One_Interp
(N
, Op_Id
, Any_Modular
);
7422 elsif Valid_Boolean_Arg
(Etype
(R
)) then
7423 Add_One_Interp
(N
, Op_Id
, Etype
(R
));
7427 Get_First_Interp
(R
, Index
, It
);
7428 while Present
(It
.Typ
) loop
7429 if Valid_Boolean_Arg
(It
.Typ
) then
7430 Add_One_Interp
(N
, Op_Id
, It
.Typ
);
7433 Get_Next_Interp
(Index
, It
);
7436 end Find_Negation_Types
;
7438 ------------------------------
7439 -- Find_Primitive_Operation --
7440 ------------------------------
7442 function Find_Primitive_Operation
(N
: Node_Id
) return Boolean is
7443 Obj
: constant Node_Id
:= Prefix
(N
);
7444 Op
: constant Node_Id
:= Selector_Name
(N
);
7451 Set_Etype
(Op
, Any_Type
);
7453 if Is_Access_Type
(Etype
(Obj
)) then
7454 Typ
:= Designated_Type
(Etype
(Obj
));
7459 if Is_Class_Wide_Type
(Typ
) then
7460 Typ
:= Root_Type
(Typ
);
7463 Prims
:= Primitive_Operations
(Typ
);
7465 Prim
:= First_Elmt
(Prims
);
7466 while Present
(Prim
) loop
7467 if Chars
(Node
(Prim
)) = Chars
(Op
) then
7468 Add_One_Interp
(Op
, Node
(Prim
), Etype
(Node
(Prim
)));
7469 Set_Etype
(N
, Etype
(Node
(Prim
)));
7475 -- Now look for class-wide operations of the type or any of its
7476 -- ancestors by iterating over the homonyms of the selector.
7479 Cls_Type
: constant Entity_Id
:= Class_Wide_Type
(Typ
);
7483 Hom
:= Current_Entity
(Op
);
7484 while Present
(Hom
) loop
7485 if (Ekind
(Hom
) = E_Procedure
7487 Ekind
(Hom
) = E_Function
)
7488 and then Scope
(Hom
) = Scope
(Typ
)
7489 and then Present
(First_Formal
(Hom
))
7491 (Base_Type
(Etype
(First_Formal
(Hom
))) = Cls_Type
7493 (Is_Access_Type
(Etype
(First_Formal
(Hom
)))
7495 Ekind
(Etype
(First_Formal
(Hom
))) =
7496 E_Anonymous_Access_Type
7499 (Designated_Type
(Etype
(First_Formal
(Hom
)))) =
7502 Add_One_Interp
(Op
, Hom
, Etype
(Hom
));
7503 Set_Etype
(N
, Etype
(Hom
));
7506 Hom
:= Homonym
(Hom
);
7510 return Etype
(Op
) /= Any_Type
;
7511 end Find_Primitive_Operation
;
7513 ----------------------
7514 -- Find_Unary_Types --
7515 ----------------------
7517 procedure Find_Unary_Types
7522 Index
: Interp_Index
;
7526 if not Is_Overloaded
(R
) then
7527 if Is_Numeric_Type
(Etype
(R
)) then
7529 -- In an instance a generic actual may be a numeric type even if
7530 -- the formal in the generic unit was not. In that case, the
7531 -- predefined operator was not a possible interpretation in the
7532 -- generic, and cannot be one in the instance, unless the operator
7533 -- is an actual of an instance.
7537 not Is_Numeric_Type
(Corresponding_Generic_Type
(Etype
(R
)))
7541 Add_One_Interp
(N
, Op_Id
, Base_Type
(Etype
(R
)));
7546 Get_First_Interp
(R
, Index
, It
);
7547 while Present
(It
.Typ
) loop
7548 if Is_Numeric_Type
(It
.Typ
) then
7552 (Corresponding_Generic_Type
(Etype
(It
.Typ
)))
7557 Add_One_Interp
(N
, Op_Id
, Base_Type
(It
.Typ
));
7561 Get_Next_Interp
(Index
, It
);
7564 end Find_Unary_Types
;
7570 function Junk_Operand
(N
: Node_Id
) return Boolean is
7574 if Error_Posted
(N
) then
7578 -- Get entity to be tested
7580 if Is_Entity_Name
(N
)
7581 and then Present
(Entity
(N
))
7585 -- An odd case, a procedure name gets converted to a very peculiar
7586 -- function call, and here is where we detect this happening.
7588 elsif Nkind
(N
) = N_Function_Call
7589 and then Is_Entity_Name
(Name
(N
))
7590 and then Present
(Entity
(Name
(N
)))
7594 -- Another odd case, there are at least some cases of selected
7595 -- components where the selected component is not marked as having
7596 -- an entity, even though the selector does have an entity
7598 elsif Nkind
(N
) = N_Selected_Component
7599 and then Present
(Entity
(Selector_Name
(N
)))
7601 Enode
:= Selector_Name
(N
);
7607 -- Now test the entity we got to see if it is a bad case
7609 case Ekind
(Entity
(Enode
)) is
7612 ("package name cannot be used as operand", Enode
);
7614 when Generic_Unit_Kind
=>
7616 ("generic unit name cannot be used as operand", Enode
);
7620 ("subtype name cannot be used as operand", Enode
);
7624 ("entry name cannot be used as operand", Enode
);
7628 ("procedure name cannot be used as operand", Enode
);
7632 ("exception name cannot be used as operand", Enode
);
7639 ("label name cannot be used as operand", Enode
);
7648 --------------------
7649 -- Operator_Check --
7650 --------------------
7652 procedure Operator_Check
(N
: Node_Id
) is
7654 Remove_Abstract_Operations
(N
);
7656 -- Test for case of no interpretation found for operator
7658 if Etype
(N
) = Any_Type
then
7660 L
: constant Node_Id
:=
7661 (if Nkind
(N
) in N_Binary_Op
then Left_Opnd
(N
) else Empty
);
7662 R
: constant Node_Id
:= Right_Opnd
(N
);
7665 -- If either operand has no type, then don't complain further,
7666 -- since this simply means that we have a propagated error.
7669 or else Etype
(R
) = Any_Type
7670 or else (Nkind
(N
) in N_Binary_Op
and then Etype
(L
) = Any_Type
)
7672 -- For the rather unusual case where one of the operands is
7673 -- a Raise_Expression, whose initial type is Any_Type, use
7674 -- the type of the other operand.
7676 if Nkind
(L
) = N_Raise_Expression
then
7677 Set_Etype
(L
, Etype
(R
));
7678 Set_Etype
(N
, Etype
(R
));
7680 elsif Nkind
(R
) = N_Raise_Expression
then
7681 Set_Etype
(R
, Etype
(L
));
7682 Set_Etype
(N
, Etype
(L
));
7687 -- We explicitly check for the case of concatenation of component
7688 -- with component to avoid reporting spurious matching array types
7689 -- that might happen to be lurking in distant packages (such as
7690 -- run-time packages). This also prevents inconsistencies in the
7691 -- messages for certain ACVC B tests, which can vary depending on
7692 -- types declared in run-time interfaces. Another improvement when
7693 -- aggregates are present is to look for a well-typed operand.
7695 elsif Present
(Candidate_Type
)
7696 and then (Nkind
(N
) /= N_Op_Concat
7697 or else Is_Array_Type
(Etype
(L
))
7698 or else Is_Array_Type
(Etype
(R
)))
7700 if Nkind
(N
) = N_Op_Concat
then
7701 if Etype
(L
) /= Any_Composite
7702 and then Is_Array_Type
(Etype
(L
))
7704 Candidate_Type
:= Etype
(L
);
7706 elsif Etype
(R
) /= Any_Composite
7707 and then Is_Array_Type
(Etype
(R
))
7709 Candidate_Type
:= Etype
(R
);
7713 Error_Msg_NE
-- CODEFIX
7714 ("operator for} is not directly visible!",
7715 N
, First_Subtype
(Candidate_Type
));
7718 U
: constant Node_Id
:=
7719 Cunit
(Get_Source_Unit
(Candidate_Type
));
7721 if Unit_Is_Visible
(U
) then
7722 Error_Msg_N
-- CODEFIX
7723 ("use clause would make operation legal!", N
);
7725 Error_Msg_NE
-- CODEFIX
7726 ("add with_clause and use_clause for&!",
7727 N
, Defining_Entity
(Unit
(U
)));
7732 -- If either operand is a junk operand (e.g. package name), then
7733 -- post appropriate error messages, but do not complain further.
7735 -- Note that the use of OR in this test instead of OR ELSE is
7736 -- quite deliberate, we may as well check both operands in the
7737 -- binary operator case.
7739 elsif Junk_Operand
(R
)
7740 or -- really mean OR here and not OR ELSE, see above
7741 (Nkind
(N
) in N_Binary_Op
and then Junk_Operand
(L
))
7745 -- The handling of user-defined literals is deferred to the second
7746 -- pass of resolution.
7748 elsif Has_Possible_User_Defined_Literal
(N
) then
7751 -- If we have a logical operator, one of whose operands is
7752 -- Boolean, then we know that the other operand cannot resolve to
7753 -- Boolean (since we got no interpretations), but in that case we
7754 -- pretty much know that the other operand should be Boolean, so
7755 -- resolve it that way (generating an error).
7757 elsif Nkind
(N
) in N_Op_And | N_Op_Or | N_Op_Xor
then
7758 if Etype
(L
) = Standard_Boolean
then
7759 Resolve
(R
, Standard_Boolean
);
7761 elsif Etype
(R
) = Standard_Boolean
then
7762 Resolve
(L
, Standard_Boolean
);
7766 -- For an arithmetic operator or comparison operator, if one
7767 -- of the operands is numeric, then we know the other operand
7768 -- is not the same numeric type. If it is a non-numeric type,
7769 -- then probably it is intended to match the other operand.
7771 elsif Nkind
(N
) in N_Op_Add
7782 -- If Allow_Integer_Address is active, check whether the
7783 -- operation becomes legal after converting an operand.
7785 if Is_Numeric_Type
(Etype
(L
))
7786 and then not Is_Numeric_Type
(Etype
(R
))
7788 if Address_Integer_Convert_OK
(Etype
(R
), Etype
(L
)) then
7790 Unchecked_Convert_To
(
7791 Standard_Address
, Relocate_Node
(L
)));
7793 Unchecked_Convert_To
(
7794 Standard_Address
, Relocate_Node
(R
)));
7796 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7797 Analyze_Comparison_Equality_Op
(N
);
7799 Analyze_Arithmetic_Op
(N
);
7802 Resolve
(R
, Etype
(L
));
7807 elsif Is_Numeric_Type
(Etype
(R
))
7808 and then not Is_Numeric_Type
(Etype
(L
))
7810 if Address_Integer_Convert_OK
(Etype
(L
), Etype
(R
)) then
7812 Unchecked_Convert_To
(
7813 Standard_Address
, Relocate_Node
(L
)));
7815 Unchecked_Convert_To
(
7816 Standard_Address
, Relocate_Node
(R
)));
7818 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7819 Analyze_Comparison_Equality_Op
(N
);
7821 Analyze_Arithmetic_Op
(N
);
7827 Resolve
(L
, Etype
(R
));
7832 elsif Allow_Integer_Address
7833 and then Is_Descendant_Of_Address
(Etype
(L
))
7834 and then Is_Descendant_Of_Address
(Etype
(R
))
7835 and then not Error_Posted
(N
)
7838 Addr_Type
: constant Entity_Id
:= Etype
(L
);
7842 Unchecked_Convert_To
(
7843 Standard_Address
, Relocate_Node
(L
)));
7845 Unchecked_Convert_To
(
7846 Standard_Address
, Relocate_Node
(R
)));
7848 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7849 Analyze_Comparison_Equality_Op
(N
);
7851 Analyze_Arithmetic_Op
(N
);
7854 -- If this is an operand in an enclosing arithmetic
7855 -- operation, Convert the result as an address so that
7856 -- arithmetic folding of address can continue.
7858 if Nkind
(Parent
(N
)) in N_Op
then
7860 Unchecked_Convert_To
(Addr_Type
, Relocate_Node
(N
)));
7866 -- Under relaxed RM semantics silently replace occurrences of
7867 -- null by System.Address_Null.
7869 elsif Null_To_Null_Address_Convert_OK
(N
) then
7870 Replace_Null_By_Null_Address
(N
);
7872 if Nkind
(N
) in N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt
then
7873 Analyze_Comparison_Equality_Op
(N
);
7875 Analyze_Arithmetic_Op
(N
);
7881 -- Comparisons on A'Access are common enough to deserve a
7884 elsif Nkind
(N
) in N_Op_Eq | N_Op_Ne
7885 and then Ekind
(Etype
(L
)) = E_Access_Attribute_Type
7886 and then Ekind
(Etype
(R
)) = E_Access_Attribute_Type
7889 ("two access attributes cannot be compared directly", N
);
7891 ("\use qualified expression for one of the operands",
7895 -- Another one for C programmers
7897 elsif Nkind
(N
) = N_Op_Concat
7898 and then Valid_Boolean_Arg
(Etype
(L
))
7899 and then Valid_Boolean_Arg
(Etype
(R
))
7901 Error_Msg_N
("invalid operands for concatenation", N
);
7902 Error_Msg_N
-- CODEFIX
7903 ("\maybe AND was meant", N
);
7906 -- A special case for comparison of access parameter with null
7908 elsif Nkind
(N
) = N_Op_Eq
7909 and then Is_Entity_Name
(L
)
7910 and then Nkind
(Parent
(Entity
(L
))) = N_Parameter_Specification
7911 and then Nkind
(Parameter_Type
(Parent
(Entity
(L
)))) =
7913 and then Nkind
(R
) = N_Null
7915 Error_Msg_N
("access parameter is not allowed to be null", L
);
7916 Error_Msg_N
("\(call would raise Constraint_Error)", L
);
7919 -- Another special case for exponentiation, where the right
7920 -- operand must be Natural, independently of the base.
7922 elsif Nkind
(N
) = N_Op_Expon
7923 and then Is_Numeric_Type
(Etype
(L
))
7924 and then not Is_Overloaded
(R
)
7926 First_Subtype
(Base_Type
(Etype
(R
))) /= Standard_Integer
7927 and then Base_Type
(Etype
(R
)) /= Universal_Integer
7929 if Ada_Version
>= Ada_2012
7930 and then Has_Dimension_System
(Etype
(L
))
7933 ("exponent for dimensioned type must be a rational" &
7934 ", found}", R
, Etype
(R
));
7937 ("exponent must be of type Natural, found}", R
, Etype
(R
));
7942 elsif Nkind
(N
) in N_Op_Eq | N_Op_Ne
then
7943 if Address_Integer_Convert_OK
(Etype
(R
), Etype
(L
)) then
7945 Unchecked_Convert_To
(
7946 Standard_Address
, Relocate_Node
(L
)));
7948 Unchecked_Convert_To
(
7949 Standard_Address
, Relocate_Node
(R
)));
7950 Analyze_Comparison_Equality_Op
(N
);
7953 -- Under relaxed RM semantics silently replace occurrences of
7954 -- null by System.Address_Null.
7956 elsif Null_To_Null_Address_Convert_OK
(N
) then
7957 Replace_Null_By_Null_Address
(N
);
7958 Analyze_Comparison_Equality_Op
(N
);
7963 -- If we fall through then just give general message
7965 Unresolved_Operator
(N
);
7970 ---------------------------------------
7971 -- Has_Possible_User_Defined_Literal --
7972 ---------------------------------------
7974 function Has_Possible_User_Defined_Literal
(N
: Node_Id
) return Boolean is
7975 R
: constant Node_Id
:= Right_Opnd
(N
);
7977 procedure Check_Literal_Opnd
(Opnd
: Node_Id
);
7978 -- If an operand is a literal to which an aspect may apply,
7979 -- add the corresponding type to operator node.
7981 ------------------------
7982 -- Check_Literal_Opnd --
7983 ------------------------
7985 procedure Check_Literal_Opnd
(Opnd
: Node_Id
) is
7987 if Nkind
(Opnd
) in N_Numeric_Or_String_Literal
7988 or else (Is_Entity_Name
(Opnd
)
7989 and then Present
(Entity
(Opnd
))
7990 and then Is_Named_Number
(Entity
(Opnd
)))
7992 Add_One_Interp
(N
, Etype
(Opnd
), Etype
(Opnd
));
7994 end Check_Literal_Opnd
;
7996 -- Start of processing for Has_Possible_User_Defined_Literal
7999 if Ada_Version
< Ada_2022
then
8003 Check_Literal_Opnd
(R
);
8005 -- Check left operand only if right one did not provide a
8006 -- possible interpretation. Note that literal types are not
8007 -- overloadable, in the sense that there is no overloadable
8008 -- entity name whose several interpretations can be used to
8009 -- indicate possible resulting types, so there is no way to
8010 -- provide more than one interpretation to the operator node.
8011 -- The choice of one operand over the other is arbitrary at
8012 -- this point, and may lead to spurious resolution when both
8013 -- operands are literals of different kinds, but the second
8014 -- pass of resolution will examine anew both operands to
8015 -- determine whether a user-defined literal may apply to
8018 if Nkind
(N
) in N_Binary_Op
and then Etype
(N
) = Any_Type
then
8019 Check_Literal_Opnd
(Left_Opnd
(N
));
8022 return Etype
(N
) /= Any_Type
;
8023 end Has_Possible_User_Defined_Literal
;
8025 -----------------------------------------------
8026 -- Nondispatching_Call_To_Abstract_Operation --
8027 -----------------------------------------------
8029 procedure Nondispatching_Call_To_Abstract_Operation
8031 Abstract_Op
: Entity_Id
)
8033 Typ
: constant Entity_Id
:= Etype
(N
);
8036 -- In an instance body, this is a runtime check, but one we know will
8037 -- fail, so give an appropriate warning. As usual this kind of warning
8038 -- is an error in SPARK mode.
8040 Error_Msg_Sloc
:= Sloc
(Abstract_Op
);
8042 if In_Instance_Body
and then SPARK_Mode
/= On
then
8044 ("??cannot call abstract operation& declared#",
8046 Error_Msg_N
("\Program_Error [??", N
);
8048 Make_Raise_Program_Error
(Sloc
(N
),
8049 Reason
=> PE_Explicit_Raise
));
8055 ("cannot call abstract operation& declared#",
8057 Set_Etype
(N
, Any_Type
);
8059 end Nondispatching_Call_To_Abstract_Operation
;
8061 ----------------------------------------------
8062 -- Possible_Type_For_Conditional_Expression --
8063 ----------------------------------------------
8065 function Possible_Type_For_Conditional_Expression
8066 (T1
, T2
: Entity_Id
) return Entity_Id
8068 function Is_Access_Protected_Subprogram_Attribute
8069 (T
: Entity_Id
) return Boolean;
8070 -- Return true if T is the type of an access-to-protected-subprogram
8073 function Is_Access_Subprogram_Attribute
(T
: Entity_Id
) return Boolean;
8074 -- Return true if T is the type of an access-to-subprogram attribute
8076 ----------------------------------------------
8077 -- Is_Access_Protected_Subprogram_Attribute --
8078 ----------------------------------------------
8080 function Is_Access_Protected_Subprogram_Attribute
8081 (T
: Entity_Id
) return Boolean
8084 return Ekind
(T
) = E_Access_Protected_Subprogram_Type
8085 and then Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
;
8086 end Is_Access_Protected_Subprogram_Attribute
;
8088 ------------------------------------
8089 -- Is_Access_Subprogram_Attribute --
8090 ------------------------------------
8092 function Is_Access_Subprogram_Attribute
(T
: Entity_Id
) return Boolean is
8094 return Ekind
(T
) = E_Access_Subprogram_Type
8095 and then Ekind
(Designated_Type
(T
)) /= E_Subprogram_Type
;
8096 end Is_Access_Subprogram_Attribute
;
8098 -- Start of processing for Possible_Type_For_Conditional_Expression
8101 -- If both types are those of similar access attributes or allocators,
8102 -- pick one of them, for example the first.
8104 if Ekind
(T1
) in E_Access_Attribute_Type | E_Allocator_Type
8105 and then Ekind
(T2
) in E_Access_Attribute_Type | E_Allocator_Type
8109 elsif Is_Access_Subprogram_Attribute
(T1
)
8110 and then Is_Access_Subprogram_Attribute
(T2
)
8112 Subtype_Conformant
(Designated_Type
(T1
), Designated_Type
(T2
))
8116 elsif Is_Access_Protected_Subprogram_Attribute
(T1
)
8117 and then Is_Access_Protected_Subprogram_Attribute
(T2
)
8119 Subtype_Conformant
(Designated_Type
(T1
), Designated_Type
(T2
))
8123 -- The other case to be considered is a pair of tagged types
8125 elsif Is_Tagged_Type
(T1
) and then Is_Tagged_Type
(T2
) then
8126 -- Covers performs the same checks when T1 or T2 are a CW type, so
8127 -- we don't need to do them again here.
8129 if not Is_Class_Wide_Type
(T1
) and then Is_Ancestor
(T1
, T2
) then
8132 elsif not Is_Class_Wide_Type
(T2
) and then Is_Ancestor
(T2
, T1
) then
8135 -- Neither type is an ancestor of the other, but they may have one in
8136 -- common, so we pick the first type as above. We could perform here
8137 -- the computation of the nearest common ancestors of T1 and T2, but
8138 -- this would require a significant amount of work and the practical
8139 -- benefit would very likely be negligible.
8145 -- Otherwise no type is possible
8150 end Possible_Type_For_Conditional_Expression
;
8152 --------------------------------
8153 -- Remove_Abstract_Operations --
8154 --------------------------------
8156 procedure Remove_Abstract_Operations
(N
: Node_Id
) is
8157 Abstract_Op
: Entity_Id
:= Empty
;
8158 Address_Descendant
: Boolean := False;
8162 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
8163 -- activate this if either extensions are enabled, or if the abstract
8164 -- operation in question comes from a predefined file. This latter test
8165 -- allows us to use abstract to make operations invisible to users. In
8166 -- particular, if type Address is non-private and abstract subprograms
8167 -- are used to hide its operators, they will be truly hidden.
8169 type Operand_Position
is (First_Op
, Second_Op
);
8170 Univ_Type
: constant Entity_Id
:= Universal_Interpretation
(N
);
8172 procedure Remove_Address_Interpretations
(Op
: Operand_Position
);
8173 -- Ambiguities may arise when the operands are literal and the address
8174 -- operations in s-auxdec are visible. In that case, remove the
8175 -- interpretation of a literal as Address, to retain the semantics
8176 -- of Address as a private type.
8178 ------------------------------------
8179 -- Remove_Address_Interpretations --
8180 ------------------------------------
8182 procedure Remove_Address_Interpretations
(Op
: Operand_Position
) is
8186 if Is_Overloaded
(N
) then
8187 Get_First_Interp
(N
, I
, It
);
8188 while Present
(It
.Nam
) loop
8189 Formal
:= First_Entity
(It
.Nam
);
8191 if Op
= Second_Op
then
8192 Next_Entity
(Formal
);
8195 if Is_Descendant_Of_Address
(Etype
(Formal
)) then
8196 Address_Descendant
:= True;
8200 Get_Next_Interp
(I
, It
);
8203 end Remove_Address_Interpretations
;
8205 -- Start of processing for Remove_Abstract_Operations
8208 if Is_Overloaded
(N
) then
8209 if Debug_Flag_V
then
8210 Write_Line
("Remove_Abstract_Operations: ");
8211 Write_Overloads
(N
);
8214 Get_First_Interp
(N
, I
, It
);
8216 while Present
(It
.Nam
) loop
8217 if Is_Overloadable
(It
.Nam
)
8218 and then Is_Abstract_Subprogram
(It
.Nam
)
8219 and then not Is_Dispatching_Operation
(It
.Nam
)
8221 Abstract_Op
:= It
.Nam
;
8223 if Is_Descendant_Of_Address
(It
.Typ
) then
8224 Address_Descendant
:= True;
8228 -- In Ada 2005, this operation does not participate in overload
8229 -- resolution. If the operation is defined in a predefined
8230 -- unit, it is one of the operations declared abstract in some
8231 -- variants of System, and it must be removed as well.
8233 elsif Ada_Version
>= Ada_2005
8234 or else In_Predefined_Unit
(It
.Nam
)
8241 Get_Next_Interp
(I
, It
);
8244 if No
(Abstract_Op
) then
8246 -- If some interpretation yields an integer type, it is still
8247 -- possible that there are address interpretations. Remove them
8248 -- if one operand is a literal, to avoid spurious ambiguities
8249 -- on systems where Address is a visible integer type.
8251 if Is_Overloaded
(N
)
8252 and then Nkind
(N
) in N_Op
8253 and then Is_Integer_Type
(Etype
(N
))
8255 if Nkind
(N
) in N_Binary_Op
then
8256 if Nkind
(Right_Opnd
(N
)) = N_Integer_Literal
then
8257 Remove_Address_Interpretations
(Second_Op
);
8259 elsif Nkind
(Left_Opnd
(N
)) = N_Integer_Literal
then
8260 Remove_Address_Interpretations
(First_Op
);
8265 elsif Nkind
(N
) in N_Op
then
8267 -- Remove interpretations that treat literals as addresses. This
8268 -- is never appropriate, even when Address is defined as a visible
8269 -- Integer type. The reason is that we would really prefer Address
8270 -- to behave as a private type, even in this case. If Address is a
8271 -- visible integer type, we get lots of overload ambiguities.
8273 if Nkind
(N
) in N_Binary_Op
then
8275 U1
: constant Boolean :=
8276 Present
(Universal_Interpretation
(Right_Opnd
(N
)));
8277 U2
: constant Boolean :=
8278 Present
(Universal_Interpretation
(Left_Opnd
(N
)));
8282 Remove_Address_Interpretations
(Second_Op
);
8286 Remove_Address_Interpretations
(First_Op
);
8289 if not (U1
and U2
) then
8291 -- Remove corresponding predefined operator, which is
8292 -- always added to the overload set.
8294 Get_First_Interp
(N
, I
, It
);
8295 while Present
(It
.Nam
) loop
8296 if Scope
(It
.Nam
) = Standard_Standard
8297 and then Base_Type
(It
.Typ
) =
8298 Base_Type
(Etype
(Abstract_Op
))
8303 Get_Next_Interp
(I
, It
);
8306 elsif Is_Overloaded
(N
)
8307 and then Present
(Univ_Type
)
8309 -- If both operands have a universal interpretation,
8310 -- it is still necessary to remove interpretations that
8311 -- yield Address. Any remaining ambiguities will be
8312 -- removed in Disambiguate.
8314 Get_First_Interp
(N
, I
, It
);
8315 while Present
(It
.Nam
) loop
8316 if Is_Descendant_Of_Address
(It
.Typ
) then
8319 elsif not Is_Type
(It
.Nam
) then
8320 Set_Entity
(N
, It
.Nam
);
8323 Get_Next_Interp
(I
, It
);
8329 elsif Nkind
(N
) = N_Function_Call
8331 (Nkind
(Name
(N
)) = N_Operator_Symbol
8333 (Nkind
(Name
(N
)) = N_Expanded_Name
8335 Nkind
(Selector_Name
(Name
(N
))) = N_Operator_Symbol
))
8339 Arg1
: constant Node_Id
:= First
(Parameter_Associations
(N
));
8340 U1
: constant Boolean :=
8341 Present
(Universal_Interpretation
(Arg1
));
8342 U2
: constant Boolean :=
8343 Present
(Next
(Arg1
)) and then
8344 Present
(Universal_Interpretation
(Next
(Arg1
)));
8348 Remove_Address_Interpretations
(First_Op
);
8352 Remove_Address_Interpretations
(Second_Op
);
8355 if not (U1
and U2
) then
8356 Get_First_Interp
(N
, I
, It
);
8357 while Present
(It
.Nam
) loop
8358 if Scope
(It
.Nam
) = Standard_Standard
8359 and then It
.Typ
= Base_Type
(Etype
(Abstract_Op
))
8364 Get_Next_Interp
(I
, It
);
8370 -- If the removal has left no valid interpretations, emit an error
8371 -- message now and label node as illegal.
8373 if Present
(Abstract_Op
) then
8374 Get_First_Interp
(N
, I
, It
);
8378 -- Removal of abstract operation left no viable candidate
8380 Nondispatching_Call_To_Abstract_Operation
(N
, Abstract_Op
);
8382 -- In Ada 2005, an abstract operation may disable predefined
8383 -- operators. Since the context is not yet known, we mark the
8384 -- predefined operators as potentially hidden. Do not include
8385 -- predefined operators when addresses are involved since this
8386 -- case is handled separately.
8388 elsif Ada_Version
>= Ada_2005
and then not Address_Descendant
then
8389 while Present
(It
.Nam
) loop
8390 if Is_Numeric_Type
(It
.Typ
)
8391 and then Scope
(It
.Typ
) = Standard_Standard
8392 and then Ekind
(It
.Nam
) = E_Operator
8394 Set_Abstract_Op
(I
, Abstract_Op
);
8397 Get_Next_Interp
(I
, It
);
8402 if Debug_Flag_V
then
8403 Write_Line
("Remove_Abstract_Operations done: ");
8404 Write_Overloads
(N
);
8407 end Remove_Abstract_Operations
;
8409 ----------------------------
8410 -- Try_Container_Indexing --
8411 ----------------------------
8413 function Try_Container_Indexing
8416 Exprs
: List_Id
) return Boolean
8418 Pref_Typ
: Entity_Id
:= Etype
(Prefix
);
8420 function Constant_Indexing_OK
return Boolean;
8421 -- Constant_Indexing is legal if there is no Variable_Indexing defined
8422 -- for the type, or else node not a target of assignment, or an actual
8423 -- for an IN OUT or OUT formal (RM 4.1.6 (11)).
8425 function Expr_Matches_In_Formal
8427 Par
: Node_Id
) return Boolean;
8428 -- Find formal corresponding to given indexed component that is an
8429 -- actual in a call. Note that the enclosing subprogram call has not
8430 -- been analyzed yet, and the parameter list is not normalized, so
8431 -- that if the argument is a parameter association we must match it
8432 -- by name and not by position.
8434 function Find_Indexing_Operations
8437 Is_Constant
: Boolean) return Node_Id
;
8438 -- Return a reference to the primitive operation of type T denoted by
8439 -- name Nam. If the operation is overloaded, the reference carries all
8440 -- interpretations. Flag Is_Constant should be set when the context is
8441 -- constant indexing.
8443 --------------------------
8444 -- Constant_Indexing_OK --
8445 --------------------------
8447 function Constant_Indexing_OK
return Boolean is
8451 if No
(Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Variable_Indexing
)) then
8454 elsif not Is_Variable
(Prefix
) then
8459 while Present
(Par
) loop
8460 if Nkind
(Parent
(Par
)) = N_Assignment_Statement
8461 and then Par
= Name
(Parent
(Par
))
8465 -- The call may be overloaded, in which case we assume that its
8466 -- resolution does not depend on the type of the parameter that
8467 -- includes the indexing operation.
8469 elsif Nkind
(Parent
(Par
)) in N_Subprogram_Call
8470 and then Is_Entity_Name
(Name
(Parent
(Par
)))
8476 -- We should look for an interpretation with the proper
8477 -- number of formals, and determine whether it is an
8478 -- In_Parameter, but for now we examine the formal that
8479 -- corresponds to the indexing, and assume that variable
8480 -- indexing is required if some interpretation has an
8481 -- assignable formal at that position. Still does not
8482 -- cover the most complex cases ???
8484 if Is_Overloaded
(Name
(Parent
(Par
))) then
8486 Proc
: constant Node_Id
:= Name
(Parent
(Par
));
8491 Get_First_Interp
(Proc
, I
, It
);
8492 while Present
(It
.Nam
) loop
8493 if not Expr_Matches_In_Formal
(It
.Nam
, Par
) then
8497 Get_Next_Interp
(I
, It
);
8501 -- All interpretations have a matching in-mode formal
8506 Proc
:= Entity
(Name
(Parent
(Par
)));
8508 -- If this is an indirect call, get formals from
8511 if Is_Access_Subprogram_Type
(Etype
(Proc
)) then
8512 Proc
:= Designated_Type
(Etype
(Proc
));
8516 return Expr_Matches_In_Formal
(Proc
, Par
);
8519 elsif Nkind
(Parent
(Par
)) = N_Object_Renaming_Declaration
then
8522 -- If the indexed component is a prefix it may be the first actual
8523 -- of a prefixed call. Retrieve the called entity, if any, and
8524 -- check its first formal. Determine if the context is a procedure
8525 -- or function call.
8527 elsif Nkind
(Parent
(Par
)) = N_Selected_Component
then
8529 Sel
: constant Node_Id
:= Selector_Name
(Parent
(Par
));
8530 Nam
: constant Entity_Id
:= Current_Entity
(Sel
);
8533 if Present
(Nam
) and then Is_Overloadable
(Nam
) then
8534 if Nkind
(Parent
(Parent
(Par
))) =
8535 N_Procedure_Call_Statement
8539 elsif Ekind
(Nam
) = E_Function
8540 and then Present
(First_Formal
(Nam
))
8542 return Ekind
(First_Formal
(Nam
)) = E_In_Parameter
;
8547 elsif Nkind
(Par
) in N_Op
then
8551 Par
:= Parent
(Par
);
8554 -- In all other cases, constant indexing is legal
8557 end Constant_Indexing_OK
;
8559 ----------------------------
8560 -- Expr_Matches_In_Formal --
8561 ----------------------------
8563 function Expr_Matches_In_Formal
8565 Par
: Node_Id
) return Boolean
8571 Formal
:= First_Formal
(Subp
);
8572 Actual
:= First
(Parameter_Associations
((Parent
(Par
))));
8574 if Nkind
(Par
) /= N_Parameter_Association
then
8576 -- Match by position
8578 while Present
(Actual
) and then Present
(Formal
) loop
8579 exit when Actual
= Par
;
8582 if Present
(Formal
) then
8583 Next_Formal
(Formal
);
8585 -- Otherwise this is a parameter mismatch, the error is
8586 -- reported elsewhere, or else variable indexing is implied.
8596 while Present
(Formal
) loop
8597 exit when Chars
(Formal
) = Chars
(Selector_Name
(Par
));
8598 Next_Formal
(Formal
);
8606 return Present
(Formal
) and then Ekind
(Formal
) = E_In_Parameter
;
8607 end Expr_Matches_In_Formal
;
8609 ------------------------------
8610 -- Find_Indexing_Operations --
8611 ------------------------------
8613 function Find_Indexing_Operations
8616 Is_Constant
: Boolean) return Node_Id
8618 procedure Inspect_Declarations
8620 Ref
: in out Node_Id
);
8621 -- Traverse the declarative list where type Typ resides and collect
8622 -- all suitable interpretations in node Ref.
8624 procedure Inspect_Primitives
8626 Ref
: in out Node_Id
);
8627 -- Traverse the list of primitive operations of type Typ and collect
8628 -- all suitable interpretations in node Ref.
8630 function Is_OK_Candidate
8631 (Subp_Id
: Entity_Id
;
8632 Typ
: Entity_Id
) return Boolean;
8633 -- Determine whether subprogram Subp_Id is a suitable indexing
8634 -- operation for type Typ. To qualify as such, the subprogram must
8635 -- be a function, have at least two parameters, and the type of the
8636 -- first parameter must be either Typ, or Typ'Class, or access [to
8637 -- constant] with designated type Typ or Typ'Class.
8639 procedure Record_Interp
(Subp_Id
: Entity_Id
; Ref
: in out Node_Id
);
8640 -- Store subprogram Subp_Id as an interpretation in node Ref
8642 --------------------------
8643 -- Inspect_Declarations --
8644 --------------------------
8646 procedure Inspect_Declarations
8648 Ref
: in out Node_Id
)
8650 Typ_Decl
: constant Node_Id
:= Declaration_Node
(Typ
);
8652 Subp_Id
: Entity_Id
;
8655 -- Ensure that the routine is not called with itypes, which lack a
8656 -- declarative node.
8658 pragma Assert
(Present
(Typ_Decl
));
8659 pragma Assert
(Is_List_Member
(Typ_Decl
));
8661 Decl
:= First
(List_Containing
(Typ_Decl
));
8662 while Present
(Decl
) loop
8663 if Nkind
(Decl
) = N_Subprogram_Declaration
then
8664 Subp_Id
:= Defining_Entity
(Decl
);
8666 if Is_OK_Candidate
(Subp_Id
, Typ
) then
8667 Record_Interp
(Subp_Id
, Ref
);
8673 end Inspect_Declarations
;
8675 ------------------------
8676 -- Inspect_Primitives --
8677 ------------------------
8679 procedure Inspect_Primitives
8681 Ref
: in out Node_Id
)
8683 Prim_Elmt
: Elmt_Id
;
8684 Prim_Id
: Entity_Id
;
8687 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
8688 while Present
(Prim_Elmt
) loop
8689 Prim_Id
:= Node
(Prim_Elmt
);
8691 if Is_OK_Candidate
(Prim_Id
, Typ
) then
8692 Record_Interp
(Prim_Id
, Ref
);
8695 Next_Elmt
(Prim_Elmt
);
8697 end Inspect_Primitives
;
8699 ---------------------
8700 -- Is_OK_Candidate --
8701 ---------------------
8703 function Is_OK_Candidate
8704 (Subp_Id
: Entity_Id
;
8705 Typ
: Entity_Id
) return Boolean
8708 Formal_Typ
: Entity_Id
;
8709 Param_Typ
: Node_Id
;
8712 -- To classify as a suitable candidate, the subprogram must be a
8713 -- function whose name matches the argument of aspect Constant or
8714 -- Variable_Indexing.
8716 if Ekind
(Subp_Id
) = E_Function
and then Chars
(Subp_Id
) = Nam
then
8717 Formal
:= First_Formal
(Subp_Id
);
8719 -- The candidate requires at least two parameters
8721 if Present
(Formal
) and then Present
(Next_Formal
(Formal
)) then
8722 Formal_Typ
:= Empty
;
8723 Param_Typ
:= Parameter_Type
(Parent
(Formal
));
8725 -- Use the designated type when the first parameter is of an
8728 if Nkind
(Param_Typ
) = N_Access_Definition
8729 and then Present
(Subtype_Mark
(Param_Typ
))
8731 -- When the context is a constant indexing, the access
8732 -- definition must be access-to-constant. This does not
8733 -- apply to variable indexing.
8736 or else Constant_Present
(Param_Typ
)
8738 Formal_Typ
:= Etype
(Subtype_Mark
(Param_Typ
));
8741 -- Otherwise use the parameter type
8744 Formal_Typ
:= Etype
(Param_Typ
);
8747 if Present
(Formal_Typ
) then
8749 -- Use the specific type when the parameter type is
8752 if Is_Class_Wide_Type
(Formal_Typ
) then
8753 Formal_Typ
:= Etype
(Base_Type
(Formal_Typ
));
8756 -- Use the full view when the parameter type is private
8759 if Is_Incomplete_Or_Private_Type
(Formal_Typ
)
8760 and then Present
(Full_View
(Formal_Typ
))
8762 Formal_Typ
:= Full_View
(Formal_Typ
);
8765 -- The type of the first parameter must denote the type
8766 -- of the container or acts as its ancestor type.
8770 or else Is_Ancestor
(Formal_Typ
, Typ
);
8776 end Is_OK_Candidate
;
8782 procedure Record_Interp
(Subp_Id
: Entity_Id
; Ref
: in out Node_Id
) is
8784 if Present
(Ref
) then
8785 Add_One_Interp
(Ref
, Subp_Id
, Etype
(Subp_Id
));
8787 -- Otherwise this is the first interpretation. Create a reference
8788 -- where all remaining interpretations will be collected.
8791 Ref
:= New_Occurrence_Of
(Subp_Id
, Sloc
(T
));
8800 -- Start of processing for Find_Indexing_Operations
8805 -- Use the specific type when the parameter type is class-wide
8807 if Is_Class_Wide_Type
(Typ
) then
8808 Typ
:= Root_Type
(Typ
);
8812 Typ
:= Underlying_Type
(Base_Type
(Typ
));
8814 Inspect_Primitives
(Typ
, Ref
);
8816 -- Now look for explicit declarations of an indexing operation.
8817 -- If the type is private the operation may be declared in the
8818 -- visible part that contains the partial view.
8820 if Is_Private_Type
(T
) then
8821 Inspect_Declarations
(T
, Ref
);
8824 Inspect_Declarations
(Typ
, Ref
);
8827 end Find_Indexing_Operations
;
8831 Loc
: constant Source_Ptr
:= Sloc
(N
);
8835 Func_Name
: Node_Id
;
8838 Is_Constant_Indexing
: Boolean := False;
8839 -- This flag reflects the nature of the container indexing. Note that
8840 -- the context may be suited for constant indexing, but the type may
8841 -- lack a Constant_Indexing annotation.
8843 -- Start of processing for Try_Container_Indexing
8846 -- Node may have been analyzed already when testing for a prefixed
8847 -- call, in which case do not redo analysis.
8849 if Present
(Generalized_Indexing
(N
)) then
8853 -- An explicit dereference needs to be created in the case of a prefix
8854 -- that's an access.
8856 -- It seems that this should be done elsewhere, but not clear where that
8857 -- should happen. Normally Insert_Explicit_Dereference is called via
8858 -- Resolve_Implicit_Dereference, called from Resolve_Indexed_Component,
8859 -- but that won't be called in this case because we transform the
8860 -- indexing to a call. Resolve_Call.Check_Prefixed_Call takes care of
8861 -- implicit dereferencing and referencing on prefixed calls, but that
8862 -- would be too late, even if we expanded to a prefix call, because
8863 -- Process_Indexed_Component will flag an error before the resolution
8866 if Is_Access_Type
(Pref_Typ
) then
8867 Pref_Typ
:= Implicitly_Designated_Type
(Pref_Typ
);
8868 Insert_Explicit_Dereference
(Prefix
);
8869 Error_Msg_NW
(Warn_On_Dereference
, "?d?implicit dereference", N
);
8874 -- If indexing a class-wide container, obtain indexing primitive from
8877 if Is_Class_Wide_Type
(C_Type
) then
8878 C_Type
:= Etype
(Base_Type
(C_Type
));
8881 -- Check whether the type has a specified indexing aspect
8885 -- The context is suitable for constant indexing, so obtain the name of
8886 -- the indexing function from aspect Constant_Indexing.
8888 if Constant_Indexing_OK
then
8890 Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Constant_Indexing
);
8893 if Present
(Func_Name
) then
8894 Is_Constant_Indexing
:= True;
8896 -- Otherwise attempt variable indexing
8900 Find_Value_Of_Aspect
(Pref_Typ
, Aspect_Variable_Indexing
);
8903 -- The type is not subject to either form of indexing, therefore the
8904 -- indexed component does not denote container indexing. If this is a
8905 -- true error, it is diagnosed by the caller.
8907 if No
(Func_Name
) then
8909 -- The prefix itself may be an indexing of a container. Rewrite it
8910 -- as such and retry.
8912 if Has_Implicit_Dereference
(Pref_Typ
) then
8913 Build_Explicit_Dereference
8914 (Prefix
, Get_Reference_Discriminant
(Pref_Typ
));
8915 return Try_Container_Indexing
(N
, Prefix
, Exprs
);
8917 -- Otherwise this is definitely not container indexing
8923 -- If the container type is derived from another container type, the
8924 -- value of the inherited aspect is the Reference operation declared
8925 -- for the parent type.
8927 -- However, Reference is also a primitive operation of the type, and the
8928 -- inherited operation has a different signature. We retrieve the right
8929 -- ones (the function may be overloaded) from the list of primitive
8930 -- operations of the derived type.
8932 -- Note that predefined containers are typically all derived from one of
8933 -- the Controlled types. The code below is motivated by containers that
8934 -- are derived from other types with a Reference aspect.
8935 -- Note as well that we need to examine the base type, given that
8936 -- the container object may be a constrained subtype or itype that
8937 -- does not have an explicit declaration.
8939 elsif Is_Derived_Type
(C_Type
)
8940 and then Etype
(First_Formal
(Entity
(Func_Name
))) /= Pref_Typ
8943 Find_Indexing_Operations
8944 (T
=> Base_Type
(C_Type
),
8945 Nam
=> Chars
(Func_Name
),
8946 Is_Constant
=> Is_Constant_Indexing
);
8949 Assoc
:= New_List
(Relocate_Node
(Prefix
));
8951 -- A generalized indexing may have nore than one index expression, so
8952 -- transfer all of them to the argument list to be used in the call.
8953 -- Note that there may be named associations, in which case the node
8954 -- was rewritten earlier as a call, and has been transformed back into
8955 -- an indexed expression to share the following processing.
8957 -- The generalized indexing node is the one on which analysis and
8958 -- resolution take place. Before expansion the original node is replaced
8959 -- with the generalized indexing node, which is a call, possibly with a
8960 -- dereference operation.
8962 -- Create argument list for function call that represents generalized
8963 -- indexing. Note that indices (i.e. actuals) may themselves be
8971 Arg
:= First
(Exprs
);
8972 while Present
(Arg
) loop
8973 New_Arg
:= Relocate_Node
(Arg
);
8975 -- The arguments can be parameter associations, in which case the
8976 -- explicit actual parameter carries the overloadings.
8978 if Nkind
(New_Arg
) /= N_Parameter_Association
then
8979 Save_Interps
(Arg
, New_Arg
);
8982 Append
(New_Arg
, Assoc
);
8987 if not Is_Overloaded
(Func_Name
) then
8988 Func
:= Entity
(Func_Name
);
8990 -- Can happen in case of e.g. cascaded errors
8997 Make_Function_Call
(Loc
,
8998 Name
=> New_Occurrence_Of
(Func
, Loc
),
8999 Parameter_Associations
=> Assoc
);
9001 Set_Parent
(Indexing
, Parent
(N
));
9002 Set_Generalized_Indexing
(N
, Indexing
);
9004 Set_Etype
(N
, Etype
(Indexing
));
9006 -- If the return type of the indexing function is a reference type,
9007 -- add the dereference as a possible interpretation. Note that the
9008 -- indexing aspect may be a function that returns the element type
9009 -- with no intervening implicit dereference, and that the reference
9010 -- discriminant is not the first discriminant.
9012 if Has_Discriminants
(Etype
(Func
)) then
9013 Check_Implicit_Dereference
(N
, Etype
(Func
));
9017 -- If there are multiple indexing functions, build a function call
9018 -- and analyze it for each of the possible interpretations.
9021 Make_Function_Call
(Loc
,
9023 Make_Identifier
(Loc
, Chars
(Func_Name
)),
9024 Parameter_Associations
=> Assoc
);
9025 Set_Parent
(Indexing
, Parent
(N
));
9026 Set_Generalized_Indexing
(N
, Indexing
);
9027 Set_Etype
(N
, Any_Type
);
9028 Set_Etype
(Name
(Indexing
), Any_Type
);
9036 Get_First_Interp
(Func_Name
, I
, It
);
9037 Set_Etype
(Indexing
, Any_Type
);
9039 -- Analyze each candidate function with the given actuals
9041 while Present
(It
.Nam
) loop
9042 Analyze_One_Call
(Indexing
, It
.Nam
, False, Success
);
9043 Get_Next_Interp
(I
, It
);
9046 -- If there are several successful candidates, resolution will
9047 -- be by result. Mark the interpretations of the function name
9050 if Is_Overloaded
(Indexing
) then
9051 Get_First_Interp
(Indexing
, I
, It
);
9053 while Present
(It
.Nam
) loop
9054 Add_One_Interp
(Name
(Indexing
), It
.Nam
, It
.Typ
);
9055 Get_Next_Interp
(I
, It
);
9059 Set_Etype
(Name
(Indexing
), Etype
(Indexing
));
9062 -- Now add the candidate interpretations to the indexing node
9063 -- itself, to be replaced later by the function call.
9065 if Is_Overloaded
(Name
(Indexing
)) then
9066 Get_First_Interp
(Name
(Indexing
), I
, It
);
9068 while Present
(It
.Nam
) loop
9069 Add_One_Interp
(N
, It
.Nam
, It
.Typ
);
9071 -- Add dereference interpretation if the result type has
9072 -- implicit reference discriminants.
9074 if Has_Discriminants
(Etype
(It
.Nam
)) then
9075 Check_Implicit_Dereference
(N
, Etype
(It
.Nam
));
9078 Get_Next_Interp
(I
, It
);
9082 Set_Etype
(N
, Etype
(Name
(Indexing
)));
9083 if Has_Discriminants
(Etype
(N
)) then
9084 Check_Implicit_Dereference
(N
, Etype
(N
));
9090 if Etype
(Indexing
) = Any_Type
then
9092 ("container cannot be indexed with&", N
, Etype
(First
(Exprs
)));
9093 Rewrite
(N
, New_Occurrence_Of
(Any_Id
, Loc
));
9097 end Try_Container_Indexing
;
9099 -----------------------
9100 -- Try_Indirect_Call --
9101 -----------------------
9103 function Try_Indirect_Call
9106 Typ
: Entity_Id
) return Boolean
9112 pragma Warnings
(Off
, Call_OK
);
9115 Normalize_Actuals
(N
, Designated_Type
(Typ
), False, Call_OK
);
9117 Actual
:= First_Actual
(N
);
9118 Formal
:= First_Formal
(Designated_Type
(Typ
));
9119 while Present
(Actual
) and then Present
(Formal
) loop
9120 if not Has_Compatible_Type
(Actual
, Etype
(Formal
)) then
9125 Next_Formal
(Formal
);
9128 if No
(Actual
) and then No
(Formal
) then
9129 Add_One_Interp
(N
, Nam
, Etype
(Designated_Type
(Typ
)));
9131 -- Nam is a candidate interpretation for the name in the call,
9132 -- if it is not an indirect call.
9134 if not Is_Type
(Nam
)
9135 and then Is_Entity_Name
(Name
(N
))
9137 Set_Entity
(Name
(N
), Nam
);
9145 end Try_Indirect_Call
;
9147 ----------------------
9148 -- Try_Indexed_Call --
9149 ----------------------
9151 function Try_Indexed_Call
9155 Skip_First
: Boolean) return Boolean
9157 Loc
: constant Source_Ptr
:= Sloc
(N
);
9158 Actuals
: constant List_Id
:= Parameter_Associations
(N
);
9163 Actual
:= First
(Actuals
);
9165 -- If the call was originally written in prefix form, skip the first
9166 -- actual, which is obviously not defaulted.
9172 Index
:= First_Index
(Typ
);
9173 while Present
(Actual
) and then Present
(Index
) loop
9175 -- If the parameter list has a named association, the expression
9176 -- is definitely a call and not an indexed component.
9178 if Nkind
(Actual
) = N_Parameter_Association
then
9182 if Is_Entity_Name
(Actual
)
9183 and then Is_Type
(Entity
(Actual
))
9184 and then No
(Next
(Actual
))
9186 -- A single actual that is a type name indicates a slice if the
9187 -- type is discrete, and an error otherwise.
9189 if Is_Discrete_Type
(Entity
(Actual
)) then
9193 Make_Function_Call
(Loc
,
9194 Name
=> Relocate_Node
(Name
(N
))),
9196 New_Occurrence_Of
(Entity
(Actual
), Sloc
(Actual
))));
9201 Error_Msg_N
("invalid use of type in expression", Actual
);
9202 Set_Etype
(N
, Any_Type
);
9207 elsif not Has_Compatible_Type
(Actual
, Etype
(Index
)) then
9215 if No
(Actual
) and then No
(Index
) then
9216 Add_One_Interp
(N
, Nam
, Component_Type
(Typ
));
9218 -- Nam is a candidate interpretation for the name in the call,
9219 -- if it is not an indirect call.
9221 if not Is_Type
(Nam
)
9222 and then Is_Entity_Name
(Name
(N
))
9224 Set_Entity
(Name
(N
), Nam
);
9231 end Try_Indexed_Call
;
9233 --------------------------
9234 -- Try_Object_Operation --
9235 --------------------------
9237 function Try_Object_Operation
9239 CW_Test_Only
: Boolean := False;
9240 Allow_Extensions
: Boolean := False) return Boolean
9242 K
: constant Node_Kind
:= Nkind
(Parent
(N
));
9243 Is_Subprg_Call
: constant Boolean := K
in N_Subprogram_Call
;
9244 Loc
: constant Source_Ptr
:= Sloc
(N
);
9245 Obj
: constant Node_Id
:= Prefix
(N
);
9247 Subprog
: constant Node_Id
:=
9248 Make_Identifier
(Sloc
(Selector_Name
(N
)),
9249 Chars
=> Chars
(Selector_Name
(N
)));
9250 -- Identifier on which possible interpretations will be collected
9252 Report_Error
: Boolean := False;
9253 -- If no candidate interpretation matches the context, redo analysis
9254 -- with Report_Error True to provide additional information.
9257 Candidate
: Entity_Id
:= Empty
;
9258 New_Call_Node
: Node_Id
:= Empty
;
9259 Node_To_Replace
: Node_Id
;
9260 Obj_Type
: Entity_Id
:= Etype
(Obj
);
9261 Success
: Boolean := False;
9263 procedure Complete_Object_Operation
9264 (Call_Node
: Node_Id
;
9265 Node_To_Replace
: Node_Id
);
9266 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
9267 -- Call_Node, insert the object (or its dereference) as the first actual
9268 -- in the call, and complete the analysis of the call.
9270 procedure Report_Ambiguity
(Op
: Entity_Id
);
9271 -- If a prefixed procedure call is ambiguous, indicate whether the call
9272 -- includes an implicit dereference or an implicit 'Access.
9274 procedure Transform_Object_Operation
9275 (Call_Node
: out Node_Id
;
9276 Node_To_Replace
: out Node_Id
);
9277 -- Transform Obj.Operation (X, Y, ...) into Operation (Obj, X, Y ...).
9278 -- Call_Node is the resulting subprogram call, Node_To_Replace is
9279 -- either N or the parent of N, and Subprog is a reference to the
9280 -- subprogram we are trying to match. Note that the transformation
9281 -- may be partially destructive for the parent of N, so it needs to
9282 -- be undone in the case where Try_Object_Operation returns false.
9284 function Try_Class_Wide_Operation
9285 (Call_Node
: Node_Id
;
9286 Node_To_Replace
: Node_Id
) return Boolean;
9287 -- Traverse all ancestor types looking for a class-wide subprogram for
9288 -- which the current operation is a valid non-dispatching call.
9290 procedure Try_One_Prefix_Interpretation
(T
: Entity_Id
);
9291 -- If prefix is overloaded, its interpretation may include different
9292 -- tagged types, and we must examine the primitive operations and the
9293 -- class-wide operations of each in order to find candidate
9294 -- interpretations for the call as a whole.
9296 function Try_Primitive_Operation
9297 (Call_Node
: Node_Id
;
9298 Node_To_Replace
: Node_Id
) return Boolean;
9299 -- Traverse the list of primitive subprograms looking for a dispatching
9300 -- operation for which the current node is a valid call.
9302 function Valid_Candidate
9305 Subp
: Entity_Id
) return Entity_Id
;
9306 -- If the subprogram is a valid interpretation, record it, and add to
9307 -- the list of interpretations of Subprog. Otherwise return Empty.
9309 -------------------------------
9310 -- Complete_Object_Operation --
9311 -------------------------------
9313 procedure Complete_Object_Operation
9314 (Call_Node
: Node_Id
;
9315 Node_To_Replace
: Node_Id
)
9317 Control
: constant Entity_Id
:= First_Formal
(Entity
(Subprog
));
9318 Formal_Type
: constant Entity_Id
:= Etype
(Control
);
9319 First_Actual
: Node_Id
;
9322 -- Place the name of the operation, with its interpretations,
9323 -- on the rewritten call.
9325 Set_Name
(Call_Node
, Subprog
);
9327 First_Actual
:= First
(Parameter_Associations
(Call_Node
));
9329 -- For cross-reference purposes, treat the new node as being in the
9330 -- source if the original one is. Set entity and type, even though
9331 -- they may be overwritten during resolution if overloaded.
9333 Set_Comes_From_Source
(Subprog
, Comes_From_Source
(N
));
9334 Set_Comes_From_Source
(Call_Node
, Comes_From_Source
(N
));
9336 if Nkind
(N
) = N_Selected_Component
9337 and then not Inside_A_Generic
9339 Set_Entity
(Selector_Name
(N
), Entity
(Subprog
));
9340 Set_Etype
(Selector_Name
(N
), Etype
(Entity
(Subprog
)));
9343 -- If need be, rewrite first actual as an explicit dereference. If
9344 -- the call is overloaded, the rewriting can only be done once the
9345 -- primitive operation is identified.
9347 if Is_Overloaded
(Subprog
) then
9349 -- The prefix itself may be overloaded, and its interpretations
9350 -- must be propagated to the new actual in the call.
9352 if Is_Overloaded
(Obj
) then
9353 Save_Interps
(Obj
, First_Actual
);
9356 Rewrite
(First_Actual
, Obj
);
9358 elsif not Is_Access_Type
(Formal_Type
)
9359 and then Is_Access_Type
(Etype
(Obj
))
9361 Rewrite
(First_Actual
,
9362 Make_Explicit_Dereference
(Sloc
(Obj
), Obj
));
9363 Analyze
(First_Actual
);
9365 -- If we need to introduce an explicit dereference, verify that
9366 -- the resulting actual is compatible with the mode of the formal.
9368 if Ekind
(First_Formal
(Entity
(Subprog
))) /= E_In_Parameter
9369 and then Is_Access_Constant
(Etype
(Obj
))
9372 ("expect variable in call to&", Prefix
(N
), Entity
(Subprog
));
9375 -- Conversely, if the formal is an access parameter and the object is
9376 -- not an access type or a reference type (i.e. a type with the
9377 -- Implicit_Dereference aspect specified), replace the actual with a
9378 -- 'Access reference. Its analysis will check that the object is
9381 elsif Is_Access_Type
(Formal_Type
)
9382 and then not Is_Access_Type
(Etype
(Obj
))
9384 (not Has_Implicit_Dereference
(Etype
(Obj
))
9386 not Is_Access_Type
(Designated_Type
(Etype
9387 (Get_Reference_Discriminant
(Etype
(Obj
))))))
9389 -- A special case: A.all'Access is illegal if A is an access to a
9390 -- constant and the context requires an access to a variable.
9392 if not Is_Access_Constant
(Formal_Type
) then
9393 if (Nkind
(Obj
) = N_Explicit_Dereference
9394 and then Is_Access_Constant
(Etype
(Prefix
(Obj
))))
9395 or else not Is_Variable
(Obj
)
9398 ("actual for & must be a variable", Obj
, Control
);
9402 Rewrite
(First_Actual
,
9403 Make_Attribute_Reference
(Loc
,
9404 Attribute_Name
=> Name_Access
,
9405 Prefix
=> Relocate_Node
(Obj
)));
9407 -- If the object is not overloaded verify that taking access of
9408 -- it is legal. Otherwise check is made during resolution.
9410 if not Is_Overloaded
(Obj
)
9411 and then not Is_Aliased_View
(Obj
)
9414 ("object in prefixed call to & must be aliased "
9415 & "(RM 4.1.3 (13 1/2))", Prefix
(First_Actual
), Subprog
);
9418 Analyze
(First_Actual
);
9421 if Is_Overloaded
(Obj
) then
9422 Save_Interps
(Obj
, First_Actual
);
9425 Rewrite
(First_Actual
, Obj
);
9428 if In_Extended_Main_Source_Unit
(Current_Scope
) then
9429 -- The operation is obtained from the dispatch table and not by
9430 -- visibility, and may be declared in a unit that is not
9431 -- explicitly referenced in the source, but is nevertheless
9432 -- required in the context of the current unit. Indicate that
9433 -- operation and its scope are referenced, to prevent spurious and
9434 -- misleading warnings. If the operation is overloaded, all
9435 -- primitives are in the same scope and we can use any of them.
9436 -- Don't do that outside the main unit since otherwise this will
9437 -- e.g. prevent the detection of some unused with clauses.
9439 Set_Referenced
(Entity
(Subprog
), True);
9440 Set_Referenced
(Scope
(Entity
(Subprog
)), True);
9443 Rewrite
(Node_To_Replace
, Call_Node
);
9445 -- Propagate the interpretations collected in subprog to the new
9446 -- function call node, to be resolved from context.
9448 if Is_Overloaded
(Subprog
) then
9449 Save_Interps
(Subprog
, Node_To_Replace
);
9452 Analyze
(Node_To_Replace
);
9454 -- If the operation has been rewritten into a call, which may get
9455 -- subsequently an explicit dereference, preserve the type on the
9456 -- original node (selected component or indexed component) for
9457 -- subsequent legality tests, e.g. Is_Variable. which examines
9458 -- the original node.
9460 if Nkind
(Node_To_Replace
) = N_Function_Call
then
9462 (Original_Node
(Node_To_Replace
), Etype
(Node_To_Replace
));
9465 end Complete_Object_Operation
;
9467 ----------------------
9468 -- Report_Ambiguity --
9469 ----------------------
9471 procedure Report_Ambiguity
(Op
: Entity_Id
) is
9472 Access_Actual
: constant Boolean :=
9473 Is_Access_Type
(Etype
(Prefix
(N
)));
9474 Access_Formal
: Boolean := False;
9477 Error_Msg_Sloc
:= Sloc
(Op
);
9479 if Present
(First_Formal
(Op
)) then
9480 Access_Formal
:= Is_Access_Type
(Etype
(First_Formal
(Op
)));
9483 if Access_Formal
and then not Access_Actual
then
9484 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9486 ("\possible interpretation "
9487 & "(inherited, with implicit 'Access) #", N
);
9490 ("\possible interpretation (with implicit 'Access) #", N
);
9493 elsif not Access_Formal
and then Access_Actual
then
9494 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9496 ("\possible interpretation "
9497 & "(inherited, with implicit dereference) #", N
);
9500 ("\possible interpretation (with implicit dereference) #", N
);
9504 if Nkind
(Parent
(Op
)) = N_Full_Type_Declaration
then
9505 Error_Msg_N
("\possible interpretation (inherited)#", N
);
9507 Error_Msg_N
-- CODEFIX
9508 ("\possible interpretation#", N
);
9511 end Report_Ambiguity
;
9513 --------------------------------
9514 -- Transform_Object_Operation --
9515 --------------------------------
9517 procedure Transform_Object_Operation
9518 (Call_Node
: out Node_Id
;
9519 Node_To_Replace
: out Node_Id
)
9521 Dummy
: constant Node_Id
:= New_Copy
(Obj
);
9522 -- Placeholder used as a first parameter in the call, replaced
9523 -- eventually by the proper object.
9525 Parent_Node
: constant Node_Id
:= Parent
(N
);
9531 -- Common case covering 1) Call to a procedure and 2) Call to a
9532 -- function that has some additional actuals.
9534 if Nkind
(Parent_Node
) in N_Subprogram_Call
9536 -- N is a selected component node containing the name of the
9537 -- subprogram. If N is not the name of the parent node we must
9538 -- not replace the parent node by the new construct. This case
9539 -- occurs when N is a parameterless call to a subprogram that
9540 -- is an actual parameter of a call to another subprogram. For
9542 -- Some_Subprogram (..., Obj.Operation, ...)
9544 and then N
= Name
(Parent_Node
)
9546 Node_To_Replace
:= Parent_Node
;
9548 Actuals
:= Parameter_Associations
(Parent_Node
);
9550 if Present
(Actuals
) then
9551 Prepend
(Dummy
, Actuals
);
9553 Actuals
:= New_List
(Dummy
);
9556 if Nkind
(Parent_Node
) = N_Procedure_Call_Statement
then
9558 Make_Procedure_Call_Statement
(Loc
,
9559 Name
=> New_Copy
(Subprog
),
9560 Parameter_Associations
=> Actuals
);
9564 Make_Function_Call
(Loc
,
9565 Name
=> New_Copy
(Subprog
),
9566 Parameter_Associations
=> Actuals
);
9569 -- Before analysis, a function call appears as an indexed component
9570 -- if there are no named associations.
9572 elsif Nkind
(Parent_Node
) = N_Indexed_Component
9573 and then N
= Prefix
(Parent_Node
)
9575 Node_To_Replace
:= Parent_Node
;
9576 Actuals
:= Expressions
(Parent_Node
);
9578 Actual
:= First
(Actuals
);
9579 while Present
(Actual
) loop
9584 Prepend
(Dummy
, Actuals
);
9587 Make_Function_Call
(Loc
,
9588 Name
=> New_Copy
(Subprog
),
9589 Parameter_Associations
=> Actuals
);
9591 -- Parameterless call: Obj.F is rewritten as F (Obj)
9594 Node_To_Replace
:= N
;
9597 Make_Function_Call
(Loc
,
9598 Name
=> New_Copy
(Subprog
),
9599 Parameter_Associations
=> New_List
(Dummy
));
9601 end Transform_Object_Operation
;
9603 ------------------------------
9604 -- Try_Class_Wide_Operation --
9605 ------------------------------
9607 function Try_Class_Wide_Operation
9608 (Call_Node
: Node_Id
;
9609 Node_To_Replace
: Node_Id
) return Boolean
9611 Anc_Type
: Entity_Id
;
9612 Matching_Op
: Entity_Id
:= Empty
;
9615 procedure Traverse_Homonyms
9616 (Anc_Type
: Entity_Id
;
9617 Error
: out Boolean);
9618 -- Traverse the homonym chain of the subprogram searching for those
9619 -- homonyms whose first formal has the Anc_Type's class-wide type,
9620 -- or an anonymous access type designating the class-wide type. If
9621 -- an ambiguity is detected, then Error is set to True.
9623 procedure Traverse_Interfaces
9624 (Anc_Type
: Entity_Id
;
9625 Error
: out Boolean);
9626 -- Traverse the list of interfaces, if any, associated with Anc_Type
9627 -- and search for acceptable class-wide homonyms associated with each
9628 -- interface. If an ambiguity is detected, then Error is set to True.
9630 -----------------------
9631 -- Traverse_Homonyms --
9632 -----------------------
9634 procedure Traverse_Homonyms
9635 (Anc_Type
: Entity_Id
;
9636 Error
: out Boolean)
9638 function First_Formal_Match
9639 (Subp_Id
: Entity_Id
;
9640 Typ
: Entity_Id
) return Boolean;
9641 -- Predicate to verify that the first foramal of class-wide
9642 -- subprogram Subp_Id matches type Typ of the prefix.
9644 ------------------------
9645 -- First_Formal_Match --
9646 ------------------------
9648 function First_Formal_Match
9649 (Subp_Id
: Entity_Id
;
9650 Typ
: Entity_Id
) return Boolean
9652 Ctrl
: constant Entity_Id
:= First_Formal
(Subp_Id
);
9658 (Base_Type
(Etype
(Ctrl
)) = Typ
9660 (Ekind
(Etype
(Ctrl
)) = E_Anonymous_Access_Type
9662 Base_Type
(Designated_Type
(Etype
(Ctrl
))) =
9664 end First_Formal_Match
;
9668 CW_Typ
: constant Entity_Id
:= Class_Wide_Type
(Anc_Type
);
9670 Candidate
: Entity_Id
;
9671 -- If homonym is a renaming, examine the renamed program
9677 -- Start of processing for Traverse_Homonyms
9682 -- Find a non-hidden operation whose first parameter is of the
9683 -- class-wide type, a subtype thereof, or an anonymous access
9684 -- to same. If in an instance, the operation can be considered
9685 -- even if hidden (it may be hidden because the instantiation
9686 -- is expanded after the containing package has been analyzed).
9687 -- If the subprogram is a generic actual in an enclosing instance,
9688 -- it appears as a renaming that is a candidate interpretation as
9691 Hom
:= Current_Entity
(Subprog
);
9692 while Present
(Hom
) loop
9693 if Ekind
(Hom
) in E_Procedure | E_Function
9694 and then Present
(Renamed_Entity
(Hom
))
9695 and then Is_Generic_Actual_Subprogram
(Hom
)
9696 and then In_Open_Scopes
(Scope
(Hom
))
9698 Candidate
:= Renamed_Entity
(Hom
);
9703 if Ekind
(Candidate
) in E_Function | E_Procedure
9704 and then (not Is_Hidden
(Candidate
) or else In_Instance
)
9705 and then Scope
(Candidate
) = Scope
(Base_Type
(Anc_Type
))
9706 and then First_Formal_Match
(Candidate
, CW_Typ
)
9708 -- If the context is a procedure call, ignore functions
9709 -- in the name of the call.
9711 if Ekind
(Candidate
) = E_Function
9712 and then Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
9713 and then N
= Name
(Parent
(N
))
9717 -- If the context is a function call, ignore procedures
9718 -- in the name of the call.
9720 elsif Ekind
(Candidate
) = E_Procedure
9721 and then Nkind
(Parent
(N
)) /= N_Procedure_Call_Statement
9726 Set_Etype
(Call_Node
, Any_Type
);
9727 Set_Is_Overloaded
(Call_Node
, False);
9730 if No
(Matching_Op
) then
9731 Hom_Ref
:= New_Occurrence_Of
(Candidate
, Sloc
(Subprog
));
9733 Set_Etype
(Call_Node
, Any_Type
);
9734 Set_Name
(Call_Node
, Hom_Ref
);
9735 Set_Parent
(Call_Node
, Parent
(Node_To_Replace
));
9740 Report
=> Report_Error
,
9742 Skip_First
=> True);
9745 Valid_Candidate
(Success
, Call_Node
, Candidate
);
9751 Report
=> Report_Error
,
9753 Skip_First
=> True);
9755 -- The same operation may be encountered on two homonym
9756 -- traversals, before and after looking at interfaces.
9757 -- Check for this case before reporting a real ambiguity.
9760 (Valid_Candidate
(Success
, Call_Node
, Candidate
))
9761 and then Nkind
(Call_Node
) /= N_Function_Call
9762 and then Candidate
/= Matching_Op
9764 Error_Msg_NE
("ambiguous call to&", N
, Hom
);
9765 Report_Ambiguity
(Matching_Op
);
9766 Report_Ambiguity
(Hom
);
9767 Check_Ambiguous_Aggregate
(New_Call_Node
);
9775 Hom
:= Homonym
(Hom
);
9777 end Traverse_Homonyms
;
9779 -------------------------
9780 -- Traverse_Interfaces --
9781 -------------------------
9783 procedure Traverse_Interfaces
9784 (Anc_Type
: Entity_Id
;
9785 Error
: out Boolean)
9787 Intface_List
: constant List_Id
:=
9788 Abstract_Interface_List
(Anc_Type
);
9794 Intface
:= First
(Intface_List
);
9795 while Present
(Intface
) loop
9797 -- Look for acceptable class-wide homonyms associated with the
9800 Traverse_Homonyms
(Etype
(Intface
), Error
);
9806 -- Continue the search by looking at each of the interface's
9807 -- associated interface ancestors.
9809 Traverse_Interfaces
(Etype
(Intface
), Error
);
9817 end Traverse_Interfaces
;
9819 -- Start of processing for Try_Class_Wide_Operation
9822 -- If we are searching only for conflicting class-wide subprograms
9823 -- then initialize directly Matching_Op with the target entity.
9825 if CW_Test_Only
then
9826 Matching_Op
:= Entity
(Selector_Name
(N
));
9829 -- Loop through ancestor types (including interfaces), traversing
9830 -- the homonym chain of the subprogram, trying out those homonyms
9831 -- whose first formal has the class-wide type of the ancestor, or
9832 -- an anonymous access type designating the class-wide type.
9834 Anc_Type
:= Obj_Type
;
9836 -- Look for a match among homonyms associated with the ancestor
9838 Traverse_Homonyms
(Anc_Type
, Error
);
9844 -- Continue the search for matches among homonyms associated with
9845 -- any interfaces implemented by the ancestor.
9847 Traverse_Interfaces
(Anc_Type
, Error
);
9853 exit when Etype
(Anc_Type
) = Anc_Type
;
9854 Anc_Type
:= Etype
(Anc_Type
);
9857 if Present
(Matching_Op
) then
9858 Set_Etype
(Call_Node
, Etype
(Matching_Op
));
9861 return Present
(Matching_Op
);
9862 end Try_Class_Wide_Operation
;
9864 -----------------------------------
9865 -- Try_One_Prefix_Interpretation --
9866 -----------------------------------
9868 procedure Try_One_Prefix_Interpretation
(T
: Entity_Id
) is
9869 Prev_Obj_Type
: constant Entity_Id
:= Obj_Type
;
9870 -- If the interpretation does not have a valid candidate type,
9871 -- preserve current value of Obj_Type for subsequent errors.
9876 if Is_Access_Type
(Obj_Type
) then
9877 Obj_Type
:= Designated_Type
(Obj_Type
);
9881 in E_Private_Subtype | E_Record_Subtype_With_Private
9883 Obj_Type
:= Base_Type
(Obj_Type
);
9886 if Is_Class_Wide_Type
(Obj_Type
) then
9887 Obj_Type
:= Etype
(Class_Wide_Type
(Obj_Type
));
9890 -- The type may have be obtained through a limited_with clause,
9891 -- in which case the primitive operations are available on its
9892 -- nonlimited view. If still incomplete, retrieve full view.
9894 if Ekind
(Obj_Type
) = E_Incomplete_Type
9895 and then From_Limited_With
(Obj_Type
)
9896 and then Has_Non_Limited_View
(Obj_Type
)
9898 Obj_Type
:= Get_Full_View
(Non_Limited_View
(Obj_Type
));
9901 -- If the object is not tagged, or the type is still an incomplete
9902 -- type, this is not a prefixed call. Restore the previous type as
9903 -- the current one is not a legal candidate.
9905 -- Extension feature: Calls with prefixed views are also supported
9906 -- for untagged types, so skip the early return when extensions are
9907 -- enabled, unless the type doesn't have a primitive operations list
9908 -- (such as in the case of predefined types).
9910 if (not Is_Tagged_Type
(Obj_Type
)
9912 (not (Core_Extensions_Allowed
or Allow_Extensions
)
9913 or else No
(Primitive_Operations
(Obj_Type
))))
9914 or else Is_Incomplete_Type
(Obj_Type
)
9916 Obj_Type
:= Prev_Obj_Type
;
9921 Dup_Call_Node
: constant Node_Id
:= New_Copy
(New_Call_Node
);
9923 Prim_Result
: Boolean := False;
9926 if not CW_Test_Only
then
9928 Try_Primitive_Operation
9929 (Call_Node
=> New_Call_Node
,
9930 Node_To_Replace
=> Node_To_Replace
);
9932 -- Extension feature: In the case where the prefix is of an
9933 -- access type, and a primitive wasn't found for the designated
9934 -- type, then if the access type has primitives we attempt a
9935 -- prefixed call using one of its primitives. (It seems that
9936 -- this isn't quite right to give preference to the designated
9937 -- type in the case where both the access and designated types
9938 -- have homographic prefixed-view operations that could result
9939 -- in an ambiguity, but handling properly may be tricky. ???)
9941 if (Core_Extensions_Allowed
or Allow_Extensions
)
9942 and then not Prim_Result
9943 and then Is_Named_Access_Type
(Prev_Obj_Type
)
9944 and then Present
(Direct_Primitive_Operations
(Prev_Obj_Type
))
9946 -- Temporarily reset Obj_Type to the original access type
9948 Obj_Type
:= Prev_Obj_Type
;
9951 Try_Primitive_Operation
9952 (Call_Node
=> New_Call_Node
,
9953 Node_To_Replace
=> Node_To_Replace
);
9955 -- Restore Obj_Type to the designated type (is this really
9956 -- necessary, or should it only be done when Prim_Result is
9959 Obj_Type
:= Designated_Type
(Obj_Type
);
9963 -- Check if there is a class-wide subprogram covering the
9964 -- primitive. This check must be done even if a candidate
9965 -- was found in order to report ambiguous calls.
9967 if not Prim_Result
then
9969 Try_Class_Wide_Operation
9970 (Call_Node
=> New_Call_Node
,
9971 Node_To_Replace
=> Node_To_Replace
);
9973 -- If we found a primitive we search for class-wide subprograms
9974 -- using a duplicate of the call node (done to avoid missing its
9975 -- decoration if there is no ambiguity).
9979 Try_Class_Wide_Operation
9980 (Call_Node
=> Dup_Call_Node
,
9981 Node_To_Replace
=> Node_To_Replace
);
9984 end Try_One_Prefix_Interpretation
;
9986 -----------------------------
9987 -- Try_Primitive_Operation --
9988 -----------------------------
9990 function Try_Primitive_Operation
9991 (Call_Node
: Node_Id
;
9992 Node_To_Replace
: Node_Id
) return Boolean
9995 Prim_Op
: Entity_Id
;
9996 Matching_Op
: Entity_Id
:= Empty
;
9997 Prim_Op_Ref
: Node_Id
:= Empty
;
9999 Corr_Type
: Entity_Id
:= Empty
;
10000 -- If the prefix is a synchronized type, the controlling type of
10001 -- the primitive operation is the corresponding record type, else
10002 -- this is the object type itself.
10004 Success
: Boolean := False;
10006 function Collect_Generic_Type_Ops
(T
: Entity_Id
) return Elist_Id
;
10007 -- For tagged types the candidate interpretations are found in
10008 -- the list of primitive operations of the type and its ancestors.
10009 -- For formal tagged types we have to find the operations declared
10010 -- in the same scope as the type (including in the generic formal
10011 -- part) because the type itself carries no primitive operations,
10012 -- except for formal derived types that inherit the operations of
10013 -- the parent and progenitors.
10015 -- If the context is a generic subprogram body, the generic formals
10016 -- are visible by name, but are not in the entity list of the
10017 -- subprogram because that list starts with the subprogram formals.
10018 -- We retrieve the candidate operations from the generic declaration.
10020 function Extended_Primitive_Ops
(T
: Entity_Id
) return Elist_Id
;
10021 -- Prefix notation can also be used on operations that are not
10022 -- primitives of the type, but are declared in the same immediate
10023 -- declarative part, which can only mean the corresponding package
10024 -- body (see RM 4.1.3 (9.2/3)). If we are in that body we extend the
10025 -- list of primitives with body operations with the same name that
10026 -- may be candidates, so that Try_Primitive_Operations can examine
10027 -- them if no real primitive is found.
10029 function Is_Private_Overriding
(Op
: Entity_Id
) return Boolean;
10030 -- An operation that overrides an inherited operation in the private
10031 -- part of its package may be hidden, but if the inherited operation
10032 -- is visible a direct call to it will dispatch to the private one,
10033 -- which is therefore a valid candidate.
10035 function Names_Match
10036 (Obj_Type
: Entity_Id
;
10037 Prim_Op
: Entity_Id
;
10038 Subprog
: Entity_Id
) return Boolean;
10039 -- Return True if the names of Prim_Op and Subprog match. If Obj_Type
10040 -- is a protected type then compare also the original name of Prim_Op
10041 -- with the name of Subprog (since the expander may have added a
10042 -- prefix to its original name --see Exp_Ch9.Build_Selected_Name).
10044 function Valid_First_Argument_Of
(Op
: Entity_Id
) return Boolean;
10045 -- Verify that the prefix, dereferenced if need be, is a valid
10046 -- controlling argument in a call to Op. The remaining actuals
10047 -- are checked in the subsequent call to Analyze_One_Call.
10049 ------------------------------
10050 -- Collect_Generic_Type_Ops --
10051 ------------------------------
10053 function Collect_Generic_Type_Ops
(T
: Entity_Id
) return Elist_Id
is
10054 Bas
: constant Entity_Id
:= Base_Type
(T
);
10055 Candidates
: constant Elist_Id
:= New_Elmt_List
;
10057 Formal
: Entity_Id
;
10059 procedure Check_Candidate
;
10060 -- The operation is a candidate if its first parameter is a
10061 -- controlling operand of the desired type.
10063 -----------------------
10064 -- Check_Candidate; --
10065 -----------------------
10067 procedure Check_Candidate
is
10069 Formal
:= First_Formal
(Subp
);
10071 if Present
(Formal
)
10072 and then Is_Controlling_Formal
(Formal
)
10074 (Base_Type
(Etype
(Formal
)) = Bas
10076 (Is_Access_Type
(Etype
(Formal
))
10077 and then Designated_Type
(Etype
(Formal
)) = Bas
))
10079 Append_Elmt
(Subp
, Candidates
);
10081 end Check_Candidate
;
10083 -- Start of processing for Collect_Generic_Type_Ops
10086 if Is_Derived_Type
(T
) then
10087 return Primitive_Operations
(T
);
10089 elsif Ekind
(Scope
(T
)) in E_Procedure | E_Function
then
10091 -- Scan the list of generic formals to find subprograms
10092 -- that may have a first controlling formal of the type.
10094 if Nkind
(Unit_Declaration_Node
(Scope
(T
))) =
10095 N_Generic_Subprogram_Declaration
10102 First
(Generic_Formal_Declarations
10103 (Unit_Declaration_Node
(Scope
(T
))));
10104 while Present
(Decl
) loop
10105 if Nkind
(Decl
) in N_Formal_Subprogram_Declaration
then
10106 Subp
:= Defining_Entity
(Decl
);
10117 -- Scan the list of entities declared in the same scope as
10118 -- the type. In general this will be an open scope, given that
10119 -- the call we are analyzing can only appear within a generic
10120 -- declaration or body (either the one that declares T, or a
10123 -- For a subtype representing a generic actual type, go to the
10126 if Is_Generic_Actual_Type
(T
) then
10127 Subp
:= First_Entity
(Scope
(Base_Type
(T
)));
10129 Subp
:= First_Entity
(Scope
(T
));
10132 while Present
(Subp
) loop
10133 if Is_Overloadable
(Subp
) then
10137 Next_Entity
(Subp
);
10142 end Collect_Generic_Type_Ops
;
10144 ----------------------------
10145 -- Extended_Primitive_Ops --
10146 ----------------------------
10148 function Extended_Primitive_Ops
(T
: Entity_Id
) return Elist_Id
is
10149 Type_Scope
: constant Entity_Id
:= Scope
(T
);
10150 Op_List
: Elist_Id
:= Primitive_Operations
(T
);
10152 if Is_Package_Or_Generic_Package
(Type_Scope
)
10153 and then ((In_Package_Body
(Type_Scope
)
10154 and then In_Open_Scopes
(Type_Scope
)) or else In_Instance_Body
)
10156 -- Retrieve list of declarations of package body if possible
10159 The_Body
: constant Node_Id
:=
10160 Corresponding_Body
(Unit_Declaration_Node
(Type_Scope
));
10162 if Present
(The_Body
) then
10164 Body_Decls
: constant List_Id
:=
10165 Declarations
(Unit_Declaration_Node
(The_Body
));
10166 Op_Found
: Boolean := False;
10167 Op
: Entity_Id
:= Current_Entity
(Subprog
);
10169 while Present
(Op
) loop
10170 if Comes_From_Source
(Op
)
10171 and then Is_Overloadable
(Op
)
10173 -- Exclude overriding primitive operations of a
10174 -- type extension declared in the package body,
10175 -- to prevent duplicates in extended list.
10177 and then not Is_Primitive
(Op
)
10178 and then Is_List_Member
10179 (Unit_Declaration_Node
(Op
))
10180 and then List_Containing
10181 (Unit_Declaration_Node
(Op
)) = Body_Decls
10183 if not Op_Found
then
10184 -- Copy list of primitives so it is not
10185 -- affected for other uses.
10187 Op_List
:= New_Copy_Elist
(Op_List
);
10191 Append_Elmt
(Op
, Op_List
);
10194 Op
:= Homonym
(Op
);
10202 end Extended_Primitive_Ops
;
10204 ---------------------------
10205 -- Is_Private_Overriding --
10206 ---------------------------
10208 function Is_Private_Overriding
(Op
: Entity_Id
) return Boolean is
10209 Visible_Op
: Entity_Id
;
10212 -- The subprogram may be overloaded with both visible and private
10213 -- entities with the same name. We have to scan the chain of
10214 -- homonyms to determine whether there is a previous implicit
10215 -- declaration in the same scope that is overridden by the
10216 -- private candidate.
10218 Visible_Op
:= Homonym
(Op
);
10219 while Present
(Visible_Op
) loop
10220 if Scope
(Op
) /= Scope
(Visible_Op
) then
10223 elsif not Comes_From_Source
(Visible_Op
)
10224 and then Alias
(Visible_Op
) = Op
10226 -- If Visible_Op or what it overrides is not hidden, then we
10227 -- have found what we're looking for.
10229 if not Is_Hidden
(Visible_Op
)
10230 or else not Is_Hidden
(Overridden_Operation
(Op
))
10236 Visible_Op
:= Homonym
(Visible_Op
);
10240 end Is_Private_Overriding
;
10246 function Names_Match
10247 (Obj_Type
: Entity_Id
;
10248 Prim_Op
: Entity_Id
;
10249 Subprog
: Entity_Id
) return Boolean is
10251 -- Common case: exact match
10253 if Chars
(Prim_Op
) = Chars
(Subprog
) then
10256 -- For protected type primitives the expander may have built the
10257 -- name of the dispatching primitive prepending the type name to
10258 -- avoid conflicts with the name of the protected subprogram (see
10259 -- Exp_Ch9.Build_Selected_Name).
10261 elsif Is_Protected_Type
(Obj_Type
) then
10263 Present
(Original_Protected_Subprogram
(Prim_Op
))
10264 and then Chars
(Original_Protected_Subprogram
(Prim_Op
)) =
10267 -- In an instance, the selector name may be a generic actual that
10268 -- renames a primitive operation of the type of the prefix.
10270 elsif In_Instance
and then Present
(Current_Entity
(Subprog
)) then
10272 Subp
: constant Entity_Id
:= Current_Entity
(Subprog
);
10275 and then Is_Subprogram
(Subp
)
10276 and then Present
(Renamed_Entity
(Subp
))
10277 and then Is_Generic_Actual_Subprogram
(Subp
)
10278 and then Chars
(Renamed_Entity
(Subp
)) = Chars
(Prim_Op
)
10288 -----------------------------
10289 -- Valid_First_Argument_Of --
10290 -----------------------------
10292 function Valid_First_Argument_Of
(Op
: Entity_Id
) return Boolean is
10293 Typ
: Entity_Id
:= Etype
(First_Formal
(Op
));
10296 if Is_Concurrent_Type
(Typ
)
10297 and then Present
(Corresponding_Record_Type
(Typ
))
10299 Typ
:= Corresponding_Record_Type
(Typ
);
10302 -- Simple case. Object may be a subtype of the tagged type or may
10303 -- be the corresponding record of a synchronized type.
10305 return Obj_Type
= Typ
10306 or else Base_Type
(Obj_Type
) = Base_Type
(Typ
)
10307 or else Corr_Type
= Typ
10309 -- Object may be of a derived type whose parent has unknown
10310 -- discriminants, in which case the type matches the underlying
10311 -- record view of its base.
10314 (Has_Unknown_Discriminants
(Typ
)
10315 and then Typ
= Underlying_Record_View
(Base_Type
(Obj_Type
)))
10317 -- Prefix can be dereferenced
10320 (Is_Access_Type
(Corr_Type
)
10321 and then Designated_Type
(Corr_Type
) = Typ
)
10323 -- Formal is an access parameter, for which the object can
10324 -- provide an access.
10327 (Ekind
(Typ
) = E_Anonymous_Access_Type
10329 Base_Type
(Designated_Type
(Typ
)) = Base_Type
(Corr_Type
));
10330 end Valid_First_Argument_Of
;
10332 -- Start of processing for Try_Primitive_Operation
10335 -- Look for subprograms in the list of primitive operations. The name
10336 -- must be identical, and the kind of call indicates the expected
10337 -- kind of operation (function or procedure). If the type is a
10338 -- (tagged) synchronized type, the primitive ops are attached to the
10339 -- corresponding record (base) type.
10341 if Is_Concurrent_Type
(Obj_Type
) then
10342 if Present
(Corresponding_Record_Type
(Obj_Type
)) then
10343 Corr_Type
:= Base_Type
(Corresponding_Record_Type
(Obj_Type
));
10344 Elmt
:= First_Elmt
(Primitive_Operations
(Corr_Type
));
10346 Corr_Type
:= Obj_Type
;
10347 Elmt
:= First_Elmt
(Collect_Generic_Type_Ops
(Obj_Type
));
10350 elsif not Is_Generic_Type
(Obj_Type
) then
10351 Corr_Type
:= Obj_Type
;
10352 Elmt
:= First_Elmt
(Extended_Primitive_Ops
(Obj_Type
));
10355 Corr_Type
:= Obj_Type
;
10356 Elmt
:= First_Elmt
(Collect_Generic_Type_Ops
(Obj_Type
));
10359 while Present
(Elmt
) loop
10360 Prim_Op
:= Node
(Elmt
);
10362 if Names_Match
(Obj_Type
, Prim_Op
, Subprog
)
10363 and then Present
(First_Formal
(Prim_Op
))
10364 and then Valid_First_Argument_Of
(Prim_Op
)
10366 (Nkind
(Call_Node
) = N_Function_Call
)
10368 (Ekind
(Prim_Op
) = E_Function
)
10370 -- Ada 2005 (AI-251): If this primitive operation corresponds
10371 -- to an immediate ancestor interface there is no need to add
10372 -- it to the list of interpretations; the corresponding aliased
10373 -- primitive is also in this list of primitive operations and
10374 -- will be used instead.
10376 if (Present
(Interface_Alias
(Prim_Op
))
10377 and then Is_Ancestor
(Find_Dispatching_Type
10378 (Alias
(Prim_Op
)), Corr_Type
))
10380 -- Do not consider hidden primitives unless the type is in an
10381 -- open scope or we are within an instance, where visibility
10382 -- is known to be correct, or else if this is an overriding
10383 -- operation in the private part for an inherited operation.
10385 or else (Is_Hidden
(Prim_Op
)
10386 and then not Is_Immediately_Visible
(Obj_Type
)
10387 and then not In_Instance
10388 and then not Is_Private_Overriding
(Prim_Op
))
10393 Set_Etype
(Call_Node
, Any_Type
);
10394 Set_Is_Overloaded
(Call_Node
, False);
10396 if No
(Matching_Op
) then
10397 Prim_Op_Ref
:= New_Occurrence_Of
(Prim_Op
, Sloc
(Subprog
));
10398 Candidate
:= Prim_Op
;
10400 Set_Parent
(Call_Node
, Parent
(Node_To_Replace
));
10402 Set_Name
(Call_Node
, Prim_Op_Ref
);
10408 Report
=> Report_Error
,
10409 Success
=> Success
,
10410 Skip_First
=> True);
10412 Matching_Op
:= Valid_Candidate
(Success
, Call_Node
, Prim_Op
);
10414 -- More than one interpretation, collect for subsequent
10415 -- disambiguation. If this is a procedure call and there
10416 -- is another match, report ambiguity now.
10422 Report
=> Report_Error
,
10423 Success
=> Success
,
10424 Skip_First
=> True);
10426 if Present
(Valid_Candidate
(Success
, Call_Node
, Prim_Op
))
10427 and then Nkind
(Call_Node
) /= N_Function_Call
10429 Error_Msg_NE
("ambiguous call to&", N
, Prim_Op
);
10430 Report_Ambiguity
(Matching_Op
);
10431 Report_Ambiguity
(Prim_Op
);
10432 Check_Ambiguous_Aggregate
(Call_Node
);
10442 if Present
(Matching_Op
) then
10443 Set_Etype
(Call_Node
, Etype
(Matching_Op
));
10446 return Present
(Matching_Op
);
10447 end Try_Primitive_Operation
;
10449 ---------------------
10450 -- Valid_Candidate --
10451 ---------------------
10453 function Valid_Candidate
10454 (Success
: Boolean;
10456 Subp
: Entity_Id
) return Entity_Id
10458 Arr_Type
: Entity_Id
;
10459 Comp_Type
: Entity_Id
;
10462 -- If the subprogram is a valid interpretation, record it in global
10463 -- variable Subprog, to collect all possible overloadings.
10466 if Subp
/= Entity
(Subprog
) then
10467 Add_One_Interp
(Subprog
, Subp
, Etype
(Subp
));
10471 -- If the call may be an indexed call, retrieve component type of
10472 -- resulting expression, and add possible interpretation.
10475 Comp_Type
:= Empty
;
10477 if Nkind
(Call
) = N_Function_Call
10478 and then Nkind
(Parent
(N
)) = N_Indexed_Component
10479 and then Needs_One_Actual
(Subp
)
10481 if Is_Array_Type
(Etype
(Subp
)) then
10482 Arr_Type
:= Etype
(Subp
);
10484 elsif Is_Access_Type
(Etype
(Subp
))
10485 and then Is_Array_Type
(Designated_Type
(Etype
(Subp
)))
10487 Arr_Type
:= Designated_Type
(Etype
(Subp
));
10491 if Present
(Arr_Type
) then
10493 -- Verify that the actuals (excluding the object) match the types
10501 Actual
:= Next
(First_Actual
(Call
));
10502 Index
:= First_Index
(Arr_Type
);
10503 while Present
(Actual
) and then Present
(Index
) loop
10504 if not Has_Compatible_Type
(Actual
, Etype
(Index
)) then
10509 Next_Actual
(Actual
);
10510 Next_Index
(Index
);
10514 and then No
(Index
)
10515 and then Present
(Arr_Type
)
10517 Comp_Type
:= Component_Type
(Arr_Type
);
10521 if Present
(Comp_Type
)
10522 and then Etype
(Subprog
) /= Comp_Type
10524 Add_One_Interp
(Subprog
, Subp
, Comp_Type
);
10528 if Etype
(Call
) /= Any_Type
then
10533 end Valid_Candidate
;
10535 -- Start of processing for Try_Object_Operation
10538 Analyze_Expression
(Obj
);
10540 -- Analyze the actuals if node is known to be a subprogram call
10542 if Is_Subprg_Call
and then N
= Name
(Parent
(N
)) then
10543 Actual
:= First
(Parameter_Associations
(Parent
(N
)));
10544 while Present
(Actual
) loop
10545 Analyze_Expression
(Actual
);
10550 -- Build a subprogram call node, using a copy of Obj as its first
10551 -- actual. This is a placeholder, to be replaced by an explicit
10552 -- dereference when needed.
10554 Transform_Object_Operation
10555 (Call_Node
=> New_Call_Node
,
10556 Node_To_Replace
=> Node_To_Replace
);
10558 Set_Etype
(New_Call_Node
, Any_Type
);
10559 Set_Etype
(Subprog
, Any_Type
);
10560 Set_Parent
(New_Call_Node
, Parent
(Node_To_Replace
));
10562 if not Is_Overloaded
(Obj
) then
10563 Try_One_Prefix_Interpretation
(Obj_Type
);
10570 Get_First_Interp
(Obj
, I
, It
);
10571 while Present
(It
.Nam
) loop
10572 Try_One_Prefix_Interpretation
(It
.Typ
);
10573 Get_Next_Interp
(I
, It
);
10578 if Etype
(New_Call_Node
) /= Any_Type
then
10580 -- No need to complete the tree transformations if we are only
10581 -- searching for conflicting class-wide subprograms
10583 if CW_Test_Only
then
10586 Complete_Object_Operation
10587 (Call_Node
=> New_Call_Node
,
10588 Node_To_Replace
=> Node_To_Replace
);
10592 elsif Present
(Candidate
) then
10594 -- The argument list is not type correct. Re-analyze with error
10595 -- reporting enabled, and use one of the possible candidates.
10596 -- In All_Errors_Mode, re-analyze all failed interpretations.
10598 if All_Errors_Mode
then
10599 Report_Error
:= True;
10600 if Try_Primitive_Operation
10601 (Call_Node
=> New_Call_Node
,
10602 Node_To_Replace
=> Node_To_Replace
)
10605 Try_Class_Wide_Operation
10606 (Call_Node
=> New_Call_Node
,
10607 Node_To_Replace
=> Node_To_Replace
)
10614 (N
=> New_Call_Node
,
10617 Success
=> Success
,
10618 Skip_First
=> True);
10620 -- The error may hot have been reported yet for overloaded
10621 -- prefixed calls, depending on the non-matching candidate,
10622 -- in which case provide a concise error now.
10624 if Serious_Errors_Detected
= 0 then
10626 ("cannot resolve prefixed call to primitive operation of&",
10631 -- No need for further errors
10636 -- There was no candidate operation, but Analyze_Selected_Component
10637 -- may continue the analysis so we need to undo the change possibly
10638 -- made to the Parent of N earlier by Transform_Object_Operation.
10641 Parent_Node
: constant Node_Id
:= Parent
(N
);
10644 if Node_To_Replace
= Parent_Node
then
10645 Remove
(First
(Parameter_Associations
(New_Call_Node
)));
10647 (Parameter_Associations
(New_Call_Node
), Parent_Node
);
10653 end Try_Object_Operation
;
10655 -------------------------
10656 -- Unresolved_Operator --
10657 -------------------------
10659 procedure Unresolved_Operator
(N
: Node_Id
) is
10660 L
: constant Node_Id
:=
10661 (if Nkind
(N
) in N_Binary_Op
then Left_Opnd
(N
) else Empty
);
10662 R
: constant Node_Id
:= Right_Opnd
(N
);
10667 -- Note that in the following messages, if the operand is overloaded we
10668 -- choose an arbitrary type to complain about, but that is probably more
10669 -- useful than not giving a type at all.
10671 if Nkind
(N
) in N_Unary_Op
then
10672 Error_Msg_Node_2
:= Etype
(R
);
10673 Error_Msg_N
("operator& not defined for}", N
);
10675 elsif Nkind
(N
) in N_Binary_Op
then
10676 if not Is_Overloaded
(L
)
10677 and then not Is_Overloaded
(R
)
10678 and then Base_Type
(Etype
(L
)) = Base_Type
(Etype
(R
))
10680 Error_Msg_Node_2
:= First_Subtype
(Etype
(R
));
10681 Error_Msg_N
("there is no applicable operator& for}", N
);
10684 -- Another attempt to find a fix: one of the candidate
10685 -- interpretations may not be use-visible. This has
10686 -- already been checked for predefined operators, so
10687 -- we examine only user-defined functions.
10689 Op_Id
:= Get_Name_Entity_Id
(Chars
(N
));
10691 while Present
(Op_Id
) loop
10692 if Ekind
(Op_Id
) /= E_Operator
10693 and then Is_Overloadable
(Op_Id
)
10694 and then not Is_Immediately_Visible
(Op_Id
)
10695 and then not In_Use
(Scope
(Op_Id
))
10696 and then not Is_Abstract_Subprogram
(Op_Id
)
10697 and then not Is_Hidden
(Op_Id
)
10698 and then Ekind
(Scope
(Op_Id
)) = E_Package
10699 and then Has_Compatible_Type
(L
, Etype
(First_Formal
(Op_Id
)))
10700 and then Present
(Next_Formal
(First_Formal
(Op_Id
)))
10702 Has_Compatible_Type
10703 (R
, Etype
(Next_Formal
(First_Formal
(Op_Id
))))
10705 Error_Msg_N
("no legal interpretation for operator&", N
);
10706 Error_Msg_NE
("\use clause on& would make operation legal",
10711 Op_Id
:= Homonym
(Op_Id
);
10715 Error_Msg_N
("invalid operand types for operator&", N
);
10717 if Nkind
(N
) /= N_Op_Concat
then
10718 Error_Msg_NE
("\left operand has}!", N
, Etype
(L
));
10719 Error_Msg_NE
("\right operand has}!", N
, Etype
(R
));
10721 -- For multiplication and division operators with
10722 -- a fixed-point operand and an integer operand,
10723 -- indicate that the integer operand should be of
10726 if Nkind
(N
) in N_Op_Multiply | N_Op_Divide
10727 and then Is_Fixed_Point_Type
(Etype
(L
))
10728 and then Is_Integer_Type
(Etype
(R
))
10730 Error_Msg_N
("\convert right operand to `Integer`", N
);
10732 elsif Nkind
(N
) = N_Op_Multiply
10733 and then Is_Fixed_Point_Type
(Etype
(R
))
10734 and then Is_Integer_Type
(Etype
(L
))
10736 Error_Msg_N
("\convert left operand to `Integer`", N
);
10739 -- For concatenation operators it is more difficult to
10740 -- determine which is the wrong operand. It is worth
10741 -- flagging explicitly an access type, for those who
10742 -- might think that a dereference happens here.
10744 elsif Is_Access_Type
(Etype
(L
)) then
10745 Error_Msg_N
("\left operand is access type", N
);
10747 elsif Is_Access_Type
(Etype
(R
)) then
10748 Error_Msg_N
("\right operand is access type", N
);
10753 end Unresolved_Operator
;
10759 procedure wpo
(T
: Entity_Id
) is
10764 if not Is_Tagged_Type
(T
) then
10768 E
:= First_Elmt
(Primitive_Operations
(Base_Type
(T
)));
10769 while Present
(E
) loop
10771 Write_Int
(Int
(Op
));
10772 Write_Str
(" === ");
10773 Write_Name
(Chars
(Op
));
10774 Write_Str
(" in ");
10775 Write_Name
(Chars
(Scope
(Op
)));