1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Debug; use Debug;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_Util; use Exp_Util;
32 with Fname; use Fname;
33 with Itypes; use Itypes;
35 with Lib.Xref; use Lib.Xref;
36 with Namet; use Namet;
37 with Namet.Sp; use Namet.Sp;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Output; use Output;
42 with Restrict; use Restrict;
43 with Rident; use Rident;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Cat; use Sem_Cat;
47 with Sem_Ch3; use Sem_Ch3;
48 with Sem_Ch6; use Sem_Ch6;
49 with Sem_Ch8; use Sem_Ch8;
50 with Sem_Disp; use Sem_Disp;
51 with Sem_Dist; use Sem_Dist;
52 with Sem_Eval; use Sem_Eval;
53 with Sem_Res; use Sem_Res;
54 with Sem_Util; use Sem_Util;
55 with Sem_Type; use Sem_Type;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Snames; use Snames;
59 with Tbuild; use Tbuild;
61 package body Sem_Ch4 is
63 -----------------------
64 -- Local Subprograms --
65 -----------------------
67 procedure Analyze_Concatenation_Rest (N : Node_Id);
68 -- Does the "rest" of the work of Analyze_Concatenation, after the left
69 -- operand has been analyzed. See Analyze_Concatenation for details.
71 procedure Analyze_Expression (N : Node_Id);
72 -- For expressions that are not names, this is just a call to analyze.
73 -- If the expression is a name, it may be a call to a parameterless
74 -- function, and if so must be converted into an explicit call node
75 -- and analyzed as such. This deproceduring must be done during the first
76 -- pass of overload resolution, because otherwise a procedure call with
77 -- overloaded actuals may fail to resolve.
79 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id);
80 -- Analyze a call of the form "+"(x, y), etc. The prefix of the call
81 -- is an operator name or an expanded name whose selector is an operator
82 -- name, and one possible interpretation is as a predefined operator.
84 procedure Analyze_Overloaded_Selected_Component (N : Node_Id);
85 -- If the prefix of a selected_component is overloaded, the proper
86 -- interpretation that yields a record type with the proper selector
87 -- name must be selected.
89 procedure Analyze_User_Defined_Binary_Op (N : Node_Id; Op_Id : Entity_Id);
90 -- Procedure to analyze a user defined binary operator, which is resolved
91 -- like a function, but instead of a list of actuals it is presented
92 -- with the left and right operands of an operator node.
94 procedure Analyze_User_Defined_Unary_Op (N : Node_Id; Op_Id : Entity_Id);
95 -- Procedure to analyze a user defined unary operator, which is resolved
96 -- like a function, but instead of a list of actuals, it is presented with
97 -- the operand of the operator node.
99 procedure Ambiguous_Operands (N : Node_Id);
100 -- for equality, membership, and comparison operators with overloaded
101 -- arguments, list possible interpretations.
103 procedure Analyze_One_Call
107 Success : out Boolean;
108 Skip_First : Boolean := False);
109 -- Check one interpretation of an overloaded subprogram name for
110 -- compatibility with the types of the actuals in a call. If there is a
111 -- single interpretation which does not match, post error if Report is
114 -- Nam is the entity that provides the formals against which the actuals
115 -- are checked. Nam is either the name of a subprogram, or the internal
116 -- subprogram type constructed for an access_to_subprogram. If the actuals
117 -- are compatible with Nam, then Nam is added to the list of candidate
118 -- interpretations for N, and Success is set to True.
120 -- The flag Skip_First is used when analyzing a call that was rewritten
121 -- from object notation. In this case the first actual may have to receive
122 -- an explicit dereference, depending on the first formal of the operation
123 -- being called. The caller will have verified that the object is legal
124 -- for the call. If the remaining parameters match, the first parameter
125 -- will rewritten as a dereference if needed, prior to completing analysis.
127 procedure Check_Misspelled_Selector
130 -- Give possible misspelling diagnostic if Sel is likely to be a mis-
131 -- spelling of one of the selectors of the Prefix. This is called by
132 -- Analyze_Selected_Component after producing an invalid selector error
135 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean;
136 -- Verify that type T is declared in scope S. Used to find interpretations
137 -- for operators given by expanded names. This is abstracted as a separate
138 -- function to handle extensions to System, where S is System, but T is
139 -- declared in the extension.
141 procedure Find_Arithmetic_Types
145 -- L and R are the operands of an arithmetic operator. Find
146 -- consistent pairs of interpretations for L and R that have a
147 -- numeric type consistent with the semantics of the operator.
149 procedure Find_Comparison_Types
153 -- L and R are operands of a comparison operator. Find consistent
154 -- pairs of interpretations for L and R.
156 procedure Find_Concatenation_Types
160 -- For the four varieties of concatenation
162 procedure Find_Equality_Types
166 -- Ditto for equality operators
168 procedure Find_Boolean_Types
172 -- Ditto for binary logical operations
174 procedure Find_Negation_Types
178 -- Find consistent interpretation for operand of negation operator
180 procedure Find_Non_Universal_Interpretations
185 -- For equality and comparison operators, the result is always boolean,
186 -- and the legality of the operation is determined from the visibility
187 -- of the operand types. If one of the operands has a universal interpre-
188 -- tation, the legality check uses some compatible non-universal
189 -- interpretation of the other operand. N can be an operator node, or
190 -- a function call whose name is an operator designator.
192 function Find_Primitive_Operation (N : Node_Id) return Boolean;
193 -- Find candidate interpretations for the name Obj.Proc when it appears
194 -- in a subprogram renaming declaration.
196 procedure Find_Unary_Types
200 -- Unary arithmetic types: plus, minus, abs
202 procedure Check_Arithmetic_Pair
206 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid
207 -- types for left and right operand. Determine whether they constitute
208 -- a valid pair for the given operator, and record the corresponding
209 -- interpretation of the operator node. The node N may be an operator
210 -- node (the usual case) or a function call whose prefix is an operator
211 -- designator. In both cases Op_Id is the operator name itself.
213 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id);
214 -- Give detailed information on overloaded call where none of the
215 -- interpretations match. N is the call node, Nam the designator for
216 -- the overloaded entity being called.
218 function Junk_Operand (N : Node_Id) return Boolean;
219 -- Test for an operand that is an inappropriate entity (e.g. a package
220 -- name or a label). If so, issue an error message and return True. If
221 -- the operand is not an inappropriate entity kind, return False.
223 procedure Operator_Check (N : Node_Id);
224 -- Verify that an operator has received some valid interpretation. If none
225 -- was found, determine whether a use clause would make the operation
226 -- legal. The variable Candidate_Type (defined in Sem_Type) is set for
227 -- every type compatible with the operator, even if the operator for the
228 -- type is not directly visible. The routine uses this type to emit a more
229 -- informative message.
231 function Process_Implicit_Dereference_Prefix
233 P : Node_Id) return Entity_Id;
234 -- Called when P is the prefix of an implicit dereference, denoting an
235 -- object E. The function returns the designated type of the prefix, taking
236 -- into account that the designated type of an anonymous access type may be
237 -- a limited view, when the non-limited view is visible.
238 -- If in semantics only mode (-gnatc or generic), the function also records
239 -- that the prefix is a reference to E, if any. Normally, such a reference
240 -- is generated only when the implicit dereference is expanded into an
241 -- explicit one, but for consistency we must generate the reference when
242 -- expansion is disabled as well.
244 procedure Remove_Abstract_Operations (N : Node_Id);
245 -- Ada 2005: implementation of AI-310. An abstract non-dispatching
246 -- operation is not a candidate interpretation.
248 function Try_Indexed_Call
252 Skip_First : Boolean) return Boolean;
253 -- If a function has defaults for all its actuals, a call to it may in fact
254 -- be an indexing on the result of the call. Try_Indexed_Call attempts the
255 -- interpretation as an indexing, prior to analysis as a call. If both are
256 -- possible, the node is overloaded with both interpretations (same symbol
257 -- but two different types). If the call is written in prefix form, the
258 -- prefix becomes the first parameter in the call, and only the remaining
259 -- actuals must be checked for the presence of defaults.
261 function Try_Indirect_Call
264 Typ : Entity_Id) return Boolean;
265 -- Similarly, a function F that needs no actuals can return an access to a
266 -- subprogram, and the call F (X) interpreted as F.all (X). In this case
267 -- the call may be overloaded with both interpretations.
269 function Try_Object_Operation (N : Node_Id) return Boolean;
270 -- Ada 2005 (AI-252): Support the object.operation notation
272 procedure wpo (T : Entity_Id);
273 pragma Warnings (Off, wpo);
274 -- Used for debugging: obtain list of primitive operations even if
275 -- type is not frozen and dispatch table is not built yet.
277 ------------------------
278 -- Ambiguous_Operands --
279 ------------------------
281 procedure Ambiguous_Operands (N : Node_Id) is
282 procedure List_Operand_Interps (Opnd : Node_Id);
284 --------------------------
285 -- List_Operand_Interps --
286 --------------------------
288 procedure List_Operand_Interps (Opnd : Node_Id) is
293 if Is_Overloaded (Opnd) then
294 if Nkind (Opnd) in N_Op then
296 elsif Nkind (Opnd) = N_Function_Call then
306 if Opnd = Left_Opnd (N) then
308 ("\left operand has the following interpretations", N);
311 ("\right operand has the following interpretations", N);
315 List_Interps (Nam, Err);
316 end List_Operand_Interps;
318 -- Start of processing for Ambiguous_Operands
321 if Nkind (N) in N_Membership_Test then
322 Error_Msg_N ("ambiguous operands for membership", N);
324 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne) then
325 Error_Msg_N ("ambiguous operands for equality", N);
328 Error_Msg_N ("ambiguous operands for comparison", N);
331 if All_Errors_Mode then
332 List_Operand_Interps (Left_Opnd (N));
333 List_Operand_Interps (Right_Opnd (N));
335 Error_Msg_N ("\use -gnatf switch for details", N);
337 end Ambiguous_Operands;
339 -----------------------
340 -- Analyze_Aggregate --
341 -----------------------
343 -- Most of the analysis of Aggregates requires that the type be known,
344 -- and is therefore put off until resolution.
346 procedure Analyze_Aggregate (N : Node_Id) is
348 if No (Etype (N)) then
349 Set_Etype (N, Any_Composite);
351 end Analyze_Aggregate;
353 -----------------------
354 -- Analyze_Allocator --
355 -----------------------
357 procedure Analyze_Allocator (N : Node_Id) is
358 Loc : constant Source_Ptr := Sloc (N);
359 Sav_Errs : constant Nat := Serious_Errors_Detected;
360 E : Node_Id := Expression (N);
361 Acc_Type : Entity_Id;
365 -- In accordance with H.4(7), the No_Allocators restriction only applies
366 -- to user-written allocators.
368 if Comes_From_Source (N) then
369 Check_Restriction (No_Allocators, N);
372 if Nkind (E) = N_Qualified_Expression then
373 Acc_Type := Create_Itype (E_Allocator_Type, N);
374 Set_Etype (Acc_Type, Acc_Type);
375 Find_Type (Subtype_Mark (E));
377 -- Analyze the qualified expression, and apply the name resolution
378 -- rule given in 4.7 (3).
381 Type_Id := Etype (E);
382 Set_Directly_Designated_Type (Acc_Type, Type_Id);
384 Resolve (Expression (E), Type_Id);
386 if Is_Limited_Type (Type_Id)
387 and then Comes_From_Source (N)
388 and then not In_Instance_Body
390 if not OK_For_Limited_Init (Expression (E)) then
391 Error_Msg_N ("initialization not allowed for limited types", N);
392 Explain_Limited_Type (Type_Id, N);
396 -- A qualified expression requires an exact match of the type,
397 -- class-wide matching is not allowed.
399 -- if Is_Class_Wide_Type (Type_Id)
400 -- and then Base_Type
401 -- (Etype (Expression (E))) /= Base_Type (Type_Id)
403 -- Wrong_Type (Expression (E), Type_Id);
406 Check_Non_Static_Context (Expression (E));
408 -- We don't analyze the qualified expression itself because it's
409 -- part of the allocator
411 Set_Etype (E, Type_Id);
413 -- Case where allocator has a subtype indication
418 Base_Typ : Entity_Id;
421 -- If the allocator includes a N_Subtype_Indication then a
422 -- constraint is present, otherwise the node is a subtype mark.
423 -- Introduce an explicit subtype declaration into the tree
424 -- defining some anonymous subtype and rewrite the allocator to
425 -- use this subtype rather than the subtype indication.
427 -- It is important to introduce the explicit subtype declaration
428 -- so that the bounds of the subtype indication are attached to
429 -- the tree in case the allocator is inside a generic unit.
431 if Nkind (E) = N_Subtype_Indication then
433 -- A constraint is only allowed for a composite type in Ada
434 -- 95. In Ada 83, a constraint is also allowed for an
435 -- access-to-composite type, but the constraint is ignored.
437 Find_Type (Subtype_Mark (E));
438 Base_Typ := Entity (Subtype_Mark (E));
440 if Is_Elementary_Type (Base_Typ) then
441 if not (Ada_Version = Ada_83
442 and then Is_Access_Type (Base_Typ))
444 Error_Msg_N ("constraint not allowed here", E);
446 if Nkind (Constraint (E)) =
447 N_Index_Or_Discriminant_Constraint
449 Error_Msg_N -- CODEFIX
450 ("\if qualified expression was meant, " &
451 "use apostrophe", Constraint (E));
455 -- Get rid of the bogus constraint:
457 Rewrite (E, New_Copy_Tree (Subtype_Mark (E)));
458 Analyze_Allocator (N);
461 -- Ada 2005, AI-363: if the designated type has a constrained
462 -- partial view, it cannot receive a discriminant constraint,
463 -- and the allocated object is unconstrained.
465 elsif Ada_Version >= Ada_05
466 and then Has_Constrained_Partial_View (Base_Typ)
469 ("constraint no allowed when type " &
470 "has a constrained partial view", Constraint (E));
473 if Expander_Active then
475 Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
478 Make_Subtype_Declaration (Loc,
479 Defining_Identifier => Def_Id,
480 Subtype_Indication => Relocate_Node (E)));
482 if Sav_Errs /= Serious_Errors_Detected
483 and then Nkind (Constraint (E)) =
484 N_Index_Or_Discriminant_Constraint
486 Error_Msg_N -- CODEFIX
487 ("if qualified expression was meant, " &
488 "use apostrophe!", Constraint (E));
491 E := New_Occurrence_Of (Def_Id, Loc);
492 Rewrite (Expression (N), E);
496 Type_Id := Process_Subtype (E, N);
497 Acc_Type := Create_Itype (E_Allocator_Type, N);
498 Set_Etype (Acc_Type, Acc_Type);
499 Set_Directly_Designated_Type (Acc_Type, Type_Id);
500 Check_Fully_Declared (Type_Id, N);
502 -- Ada 2005 (AI-231): If the designated type is itself an access
503 -- type that excludes null, its default initialization will
504 -- be a null object, and we can insert an unconditional raise
505 -- before the allocator.
507 if Can_Never_Be_Null (Type_Id) then
509 Not_Null_Check : constant Node_Id :=
510 Make_Raise_Constraint_Error (Sloc (E),
511 Reason => CE_Null_Not_Allowed);
513 if Expander_Active then
514 Insert_Action (N, Not_Null_Check);
515 Analyze (Not_Null_Check);
517 Error_Msg_N ("null value not allowed here?", E);
522 -- Check restriction against dynamically allocated protected
523 -- objects. Note that when limited aggregates are supported,
524 -- a similar test should be applied to an allocator with a
525 -- qualified expression ???
527 if Is_Protected_Type (Type_Id) then
528 Check_Restriction (No_Protected_Type_Allocators, N);
531 -- Check for missing initialization. Skip this check if we already
532 -- had errors on analyzing the allocator, since in that case these
533 -- are probably cascaded errors.
535 if Is_Indefinite_Subtype (Type_Id)
536 and then Serious_Errors_Detected = Sav_Errs
538 if Is_Class_Wide_Type (Type_Id) then
540 ("initialization required in class-wide allocation", N);
542 if Ada_Version < Ada_05
543 and then Is_Limited_Type (Type_Id)
545 Error_Msg_N ("unconstrained allocation not allowed", N);
547 if Is_Array_Type (Type_Id) then
549 ("\constraint with array bounds required", N);
551 elsif Has_Unknown_Discriminants (Type_Id) then
554 else pragma Assert (Has_Discriminants (Type_Id));
556 ("\constraint with discriminant values required", N);
559 -- Limited Ada 2005 and general non-limited case
563 ("uninitialized unconstrained allocation not allowed",
566 if Is_Array_Type (Type_Id) then
568 ("\qualified expression or constraint with " &
569 "array bounds required", N);
571 elsif Has_Unknown_Discriminants (Type_Id) then
572 Error_Msg_N ("\qualified expression required", N);
574 else pragma Assert (Has_Discriminants (Type_Id));
576 ("\qualified expression or constraint with " &
577 "discriminant values required", N);
585 if Is_Abstract_Type (Type_Id) then
586 Error_Msg_N ("cannot allocate abstract object", E);
589 if Has_Task (Designated_Type (Acc_Type)) then
590 Check_Restriction (No_Tasking, N);
591 Check_Restriction (Max_Tasks, N);
592 Check_Restriction (No_Task_Allocators, N);
595 -- If the No_Streams restriction is set, check that the type of the
596 -- object is not, and does not contain, any subtype derived from
597 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
598 -- Has_Stream just for efficiency reasons. There is no point in
599 -- spending time on a Has_Stream check if the restriction is not set.
601 if Restrictions.Set (No_Streams) then
602 if Has_Stream (Designated_Type (Acc_Type)) then
603 Check_Restriction (No_Streams, N);
607 Set_Etype (N, Acc_Type);
609 if not Is_Library_Level_Entity (Acc_Type) then
610 Check_Restriction (No_Local_Allocators, N);
613 if Serious_Errors_Detected > Sav_Errs then
614 Set_Error_Posted (N);
615 Set_Etype (N, Any_Type);
617 end Analyze_Allocator;
619 ---------------------------
620 -- Analyze_Arithmetic_Op --
621 ---------------------------
623 procedure Analyze_Arithmetic_Op (N : Node_Id) is
624 L : constant Node_Id := Left_Opnd (N);
625 R : constant Node_Id := Right_Opnd (N);
629 Candidate_Type := Empty;
630 Analyze_Expression (L);
631 Analyze_Expression (R);
633 -- If the entity is already set, the node is the instantiation of a
634 -- generic node with a non-local reference, or was manufactured by a
635 -- call to Make_Op_xxx. In either case the entity is known to be valid,
636 -- and we do not need to collect interpretations, instead we just get
637 -- the single possible interpretation.
641 if Present (Op_Id) then
642 if Ekind (Op_Id) = E_Operator then
644 if Nkind_In (N, N_Op_Divide, N_Op_Mod, N_Op_Multiply, N_Op_Rem)
645 and then Treat_Fixed_As_Integer (N)
649 Set_Etype (N, Any_Type);
650 Find_Arithmetic_Types (L, R, Op_Id, N);
654 Set_Etype (N, Any_Type);
655 Add_One_Interp (N, Op_Id, Etype (Op_Id));
658 -- Entity is not already set, so we do need to collect interpretations
661 Op_Id := Get_Name_Entity_Id (Chars (N));
662 Set_Etype (N, Any_Type);
664 while Present (Op_Id) loop
665 if Ekind (Op_Id) = E_Operator
666 and then Present (Next_Entity (First_Entity (Op_Id)))
668 Find_Arithmetic_Types (L, R, Op_Id, N);
670 -- The following may seem superfluous, because an operator cannot
671 -- be generic, but this ignores the cleverness of the author of
674 elsif Is_Overloadable (Op_Id) then
675 Analyze_User_Defined_Binary_Op (N, Op_Id);
678 Op_Id := Homonym (Op_Id);
683 end Analyze_Arithmetic_Op;
689 -- Function, procedure, and entry calls are checked here. The Name in
690 -- the call may be overloaded. The actuals have been analyzed and may
691 -- themselves be overloaded. On exit from this procedure, the node N
692 -- may have zero, one or more interpretations. In the first case an
693 -- error message is produced. In the last case, the node is flagged
694 -- as overloaded and the interpretations are collected in All_Interp.
696 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
697 -- the type-checking is similar to that of other calls.
699 procedure Analyze_Call (N : Node_Id) is
700 Actuals : constant List_Id := Parameter_Associations (N);
705 Success : Boolean := False;
707 Deref : Boolean := False;
708 -- Flag indicates whether an interpretation of the prefix is a
709 -- parameterless call that returns an access_to_subprogram.
711 function Name_Denotes_Function return Boolean;
712 -- If the type of the name is an access to subprogram, this may be the
713 -- type of a name, or the return type of the function being called. If
714 -- the name is not an entity then it can denote a protected function.
715 -- Until we distinguish Etype from Return_Type, we must use this routine
716 -- to resolve the meaning of the name in the call.
718 procedure No_Interpretation;
719 -- Output error message when no valid interpretation exists
721 ---------------------------
722 -- Name_Denotes_Function --
723 ---------------------------
725 function Name_Denotes_Function return Boolean is
727 if Is_Entity_Name (Nam) then
728 return Ekind (Entity (Nam)) = E_Function;
730 elsif Nkind (Nam) = N_Selected_Component then
731 return Ekind (Entity (Selector_Name (Nam))) = E_Function;
736 end Name_Denotes_Function;
738 -----------------------
739 -- No_Interpretation --
740 -----------------------
742 procedure No_Interpretation is
743 L : constant Boolean := Is_List_Member (N);
744 K : constant Node_Kind := Nkind (Parent (N));
747 -- If the node is in a list whose parent is not an expression then it
748 -- must be an attempted procedure call.
750 if L and then K not in N_Subexpr then
751 if Ekind (Entity (Nam)) = E_Generic_Procedure then
753 ("must instantiate generic procedure& before call",
757 ("procedure or entry name expected", Nam);
760 -- Check for tasking cases where only an entry call will do
763 and then Nkind_In (K, N_Entry_Call_Alternative,
764 N_Triggering_Alternative)
766 Error_Msg_N ("entry name expected", Nam);
768 -- Otherwise give general error message
771 Error_Msg_N ("invalid prefix in call", Nam);
773 end No_Interpretation;
775 -- Start of processing for Analyze_Call
778 -- Initialize the type of the result of the call to the error type,
779 -- which will be reset if the type is successfully resolved.
781 Set_Etype (N, Any_Type);
785 if not Is_Overloaded (Nam) then
787 -- Only one interpretation to check
789 if Ekind (Etype (Nam)) = E_Subprogram_Type then
790 Nam_Ent := Etype (Nam);
792 -- If the prefix is an access_to_subprogram, this may be an indirect
793 -- call. This is the case if the name in the call is not an entity
794 -- name, or if it is a function name in the context of a procedure
795 -- call. In this latter case, we have a call to a parameterless
796 -- function that returns a pointer_to_procedure which is the entity
797 -- being called. Finally, F (X) may be a call to a parameterless
798 -- function that returns a pointer to a function with parameters.
800 elsif Is_Access_Type (Etype (Nam))
801 and then Ekind (Designated_Type (Etype (Nam))) = E_Subprogram_Type
803 (not Name_Denotes_Function
804 or else Nkind (N) = N_Procedure_Call_Statement
806 (Nkind (Parent (N)) /= N_Explicit_Dereference
807 and then Is_Entity_Name (Nam)
808 and then No (First_Formal (Entity (Nam)))
809 and then Present (Actuals)))
811 Nam_Ent := Designated_Type (Etype (Nam));
812 Insert_Explicit_Dereference (Nam);
814 -- Selected component case. Simple entry or protected operation,
815 -- where the entry name is given by the selector name.
817 elsif Nkind (Nam) = N_Selected_Component then
818 Nam_Ent := Entity (Selector_Name (Nam));
820 if Ekind (Nam_Ent) /= E_Entry
821 and then Ekind (Nam_Ent) /= E_Entry_Family
822 and then Ekind (Nam_Ent) /= E_Function
823 and then Ekind (Nam_Ent) /= E_Procedure
825 Error_Msg_N ("name in call is not a callable entity", Nam);
826 Set_Etype (N, Any_Type);
830 -- If the name is an Indexed component, it can be a call to a member
831 -- of an entry family. The prefix must be a selected component whose
832 -- selector is the entry. Analyze_Procedure_Call normalizes several
833 -- kinds of call into this form.
835 elsif Nkind (Nam) = N_Indexed_Component then
836 if Nkind (Prefix (Nam)) = N_Selected_Component then
837 Nam_Ent := Entity (Selector_Name (Prefix (Nam)));
839 Error_Msg_N ("name in call is not a callable entity", Nam);
840 Set_Etype (N, Any_Type);
844 elsif not Is_Entity_Name (Nam) then
845 Error_Msg_N ("name in call is not a callable entity", Nam);
846 Set_Etype (N, Any_Type);
850 Nam_Ent := Entity (Nam);
852 -- If no interpretations, give error message
854 if not Is_Overloadable (Nam_Ent) then
860 -- Operations generated for RACW stub types are called only through
861 -- dispatching, and can never be the static interpretation of a call.
863 if Is_RACW_Stub_Type_Operation (Nam_Ent) then
868 Analyze_One_Call (N, Nam_Ent, True, Success);
870 -- If this is an indirect call, the return type of the access_to
871 -- subprogram may be an incomplete type. At the point of the call,
872 -- use the full type if available, and at the same time update
873 -- the return type of the access_to_subprogram.
876 and then Nkind (Nam) = N_Explicit_Dereference
877 and then Ekind (Etype (N)) = E_Incomplete_Type
878 and then Present (Full_View (Etype (N)))
880 Set_Etype (N, Full_View (Etype (N)));
881 Set_Etype (Nam_Ent, Etype (N));
885 -- An overloaded selected component must denote overloaded operations
886 -- of a concurrent type. The interpretations are attached to the
887 -- simple name of those operations.
889 if Nkind (Nam) = N_Selected_Component then
890 Nam := Selector_Name (Nam);
893 Get_First_Interp (Nam, X, It);
895 while Present (It.Nam) loop
899 -- Name may be call that returns an access to subprogram, or more
900 -- generally an overloaded expression one of whose interpretations
901 -- yields an access to subprogram. If the name is an entity, we
902 -- do not dereference, because the node is a call that returns
903 -- the access type: note difference between f(x), where the call
904 -- may return an access subprogram type, and f(x)(y), where the
905 -- type returned by the call to f is implicitly dereferenced to
906 -- analyze the outer call.
908 if Is_Access_Type (Nam_Ent) then
909 Nam_Ent := Designated_Type (Nam_Ent);
911 elsif Is_Access_Type (Etype (Nam_Ent))
913 (not Is_Entity_Name (Nam)
914 or else Nkind (N) = N_Procedure_Call_Statement)
915 and then Ekind (Designated_Type (Etype (Nam_Ent)))
918 Nam_Ent := Designated_Type (Etype (Nam_Ent));
920 if Is_Entity_Name (Nam) then
925 Analyze_One_Call (N, Nam_Ent, False, Success);
927 -- If the interpretation succeeds, mark the proper type of the
928 -- prefix (any valid candidate will do). If not, remove the
929 -- candidate interpretation. This only needs to be done for
930 -- overloaded protected operations, for other entities disambi-
931 -- guation is done directly in Resolve.
935 and then Nkind (Parent (N)) /= N_Explicit_Dereference
937 Set_Entity (Nam, It.Nam);
938 Insert_Explicit_Dereference (Nam);
939 Set_Etype (Nam, Nam_Ent);
942 Set_Etype (Nam, It.Typ);
945 elsif Nkind_In (Name (N), N_Selected_Component,
951 Get_Next_Interp (X, It);
954 -- If the name is the result of a function call, it can only
955 -- be a call to a function returning an access to subprogram.
956 -- Insert explicit dereference.
958 if Nkind (Nam) = N_Function_Call then
959 Insert_Explicit_Dereference (Nam);
962 if Etype (N) = Any_Type then
964 -- None of the interpretations is compatible with the actuals
966 Diagnose_Call (N, Nam);
968 -- Special checks for uninstantiated put routines
970 if Nkind (N) = N_Procedure_Call_Statement
971 and then Is_Entity_Name (Nam)
972 and then Chars (Nam) = Name_Put
973 and then List_Length (Actuals) = 1
976 Arg : constant Node_Id := First (Actuals);
980 if Nkind (Arg) = N_Parameter_Association then
981 Typ := Etype (Explicit_Actual_Parameter (Arg));
986 if Is_Signed_Integer_Type (Typ) then
988 ("possible missing instantiation of " &
989 "'Text_'I'O.'Integer_'I'O!", Nam);
991 elsif Is_Modular_Integer_Type (Typ) then
993 ("possible missing instantiation of " &
994 "'Text_'I'O.'Modular_'I'O!", Nam);
996 elsif Is_Floating_Point_Type (Typ) then
998 ("possible missing instantiation of " &
999 "'Text_'I'O.'Float_'I'O!", Nam);
1001 elsif Is_Ordinary_Fixed_Point_Type (Typ) then
1003 ("possible missing instantiation of " &
1004 "'Text_'I'O.'Fixed_'I'O!", Nam);
1006 elsif Is_Decimal_Fixed_Point_Type (Typ) then
1008 ("possible missing instantiation of " &
1009 "'Text_'I'O.'Decimal_'I'O!", Nam);
1011 elsif Is_Enumeration_Type (Typ) then
1013 ("possible missing instantiation of " &
1014 "'Text_'I'O.'Enumeration_'I'O!", Nam);
1019 elsif not Is_Overloaded (N)
1020 and then Is_Entity_Name (Nam)
1022 -- Resolution yields a single interpretation. Verify that the
1023 -- reference has capitalization consistent with the declaration.
1025 Set_Entity_With_Style_Check (Nam, Entity (Nam));
1026 Generate_Reference (Entity (Nam), Nam);
1028 Set_Etype (Nam, Etype (Entity (Nam)));
1030 Remove_Abstract_Operations (N);
1037 ---------------------------
1038 -- Analyze_Comparison_Op --
1039 ---------------------------
1041 procedure Analyze_Comparison_Op (N : Node_Id) is
1042 L : constant Node_Id := Left_Opnd (N);
1043 R : constant Node_Id := Right_Opnd (N);
1044 Op_Id : Entity_Id := Entity (N);
1047 Set_Etype (N, Any_Type);
1048 Candidate_Type := Empty;
1050 Analyze_Expression (L);
1051 Analyze_Expression (R);
1053 if Present (Op_Id) then
1054 if Ekind (Op_Id) = E_Operator then
1055 Find_Comparison_Types (L, R, Op_Id, N);
1057 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1060 if Is_Overloaded (L) then
1061 Set_Etype (L, Intersect_Types (L, R));
1065 Op_Id := Get_Name_Entity_Id (Chars (N));
1066 while Present (Op_Id) loop
1067 if Ekind (Op_Id) = E_Operator then
1068 Find_Comparison_Types (L, R, Op_Id, N);
1070 Analyze_User_Defined_Binary_Op (N, Op_Id);
1073 Op_Id := Homonym (Op_Id);
1078 end Analyze_Comparison_Op;
1080 ---------------------------
1081 -- Analyze_Concatenation --
1082 ---------------------------
1084 procedure Analyze_Concatenation (N : Node_Id) is
1086 -- We wish to avoid deep recursion, because concatenations are often
1087 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1088 -- operands nonrecursively until we find something that is not a
1089 -- concatenation (A in this case), or has already been analyzed. We
1090 -- analyze that, and then walk back up the tree following Parent
1091 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1092 -- work at each level. The Parent pointers allow us to avoid recursion,
1093 -- and thus avoid running out of memory.
1099 Candidate_Type := Empty;
1101 -- The following code is equivalent to:
1103 -- Set_Etype (N, Any_Type);
1104 -- Analyze_Expression (Left_Opnd (N));
1105 -- Analyze_Concatenation_Rest (N);
1107 -- where the Analyze_Expression call recurses back here if the left
1108 -- operand is a concatenation.
1110 -- Walk down left operands
1113 Set_Etype (NN, Any_Type);
1114 L := Left_Opnd (NN);
1115 exit when Nkind (L) /= N_Op_Concat or else Analyzed (L);
1119 -- Now (given the above example) NN is A&B and L is A
1121 -- First analyze L ...
1123 Analyze_Expression (L);
1125 -- ... then walk NN back up until we reach N (where we started), calling
1126 -- Analyze_Concatenation_Rest along the way.
1129 Analyze_Concatenation_Rest (NN);
1133 end Analyze_Concatenation;
1135 --------------------------------
1136 -- Analyze_Concatenation_Rest --
1137 --------------------------------
1139 -- If the only one-dimensional array type in scope is String,
1140 -- this is the resulting type of the operation. Otherwise there
1141 -- will be a concatenation operation defined for each user-defined
1142 -- one-dimensional array.
1144 procedure Analyze_Concatenation_Rest (N : Node_Id) is
1145 L : constant Node_Id := Left_Opnd (N);
1146 R : constant Node_Id := Right_Opnd (N);
1147 Op_Id : Entity_Id := Entity (N);
1152 Analyze_Expression (R);
1154 -- If the entity is present, the node appears in an instance, and
1155 -- denotes a predefined concatenation operation. The resulting type is
1156 -- obtained from the arguments when possible. If the arguments are
1157 -- aggregates, the array type and the concatenation type must be
1160 if Present (Op_Id) then
1161 if Ekind (Op_Id) = E_Operator then
1163 LT := Base_Type (Etype (L));
1164 RT := Base_Type (Etype (R));
1166 if Is_Array_Type (LT)
1167 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
1169 Add_One_Interp (N, Op_Id, LT);
1171 elsif Is_Array_Type (RT)
1172 and then LT = Base_Type (Component_Type (RT))
1174 Add_One_Interp (N, Op_Id, RT);
1176 -- If one operand is a string type or a user-defined array type,
1177 -- and the other is a literal, result is of the specific type.
1180 (Root_Type (LT) = Standard_String
1181 or else Scope (LT) /= Standard_Standard)
1182 and then Etype (R) = Any_String
1184 Add_One_Interp (N, Op_Id, LT);
1187 (Root_Type (RT) = Standard_String
1188 or else Scope (RT) /= Standard_Standard)
1189 and then Etype (L) = Any_String
1191 Add_One_Interp (N, Op_Id, RT);
1193 elsif not Is_Generic_Type (Etype (Op_Id)) then
1194 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1197 -- Type and its operations must be visible
1199 Set_Entity (N, Empty);
1200 Analyze_Concatenation (N);
1204 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1208 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
1209 while Present (Op_Id) loop
1210 if Ekind (Op_Id) = E_Operator then
1212 -- Do not consider operators declared in dead code, they can
1213 -- not be part of the resolution.
1215 if Is_Eliminated (Op_Id) then
1218 Find_Concatenation_Types (L, R, Op_Id, N);
1222 Analyze_User_Defined_Binary_Op (N, Op_Id);
1225 Op_Id := Homonym (Op_Id);
1230 end Analyze_Concatenation_Rest;
1232 ------------------------------------
1233 -- Analyze_Conditional_Expression --
1234 ------------------------------------
1236 procedure Analyze_Conditional_Expression (N : Node_Id) is
1237 Condition : constant Node_Id := First (Expressions (N));
1238 Then_Expr : constant Node_Id := Next (Condition);
1239 Else_Expr : constant Node_Id := Next (Then_Expr);
1241 Analyze_Expression (Condition);
1242 Analyze_Expression (Then_Expr);
1243 Analyze_Expression (Else_Expr);
1244 Set_Etype (N, Etype (Then_Expr));
1245 end Analyze_Conditional_Expression;
1247 -------------------------
1248 -- Analyze_Equality_Op --
1249 -------------------------
1251 procedure Analyze_Equality_Op (N : Node_Id) is
1252 Loc : constant Source_Ptr := Sloc (N);
1253 L : constant Node_Id := Left_Opnd (N);
1254 R : constant Node_Id := Right_Opnd (N);
1258 Set_Etype (N, Any_Type);
1259 Candidate_Type := Empty;
1261 Analyze_Expression (L);
1262 Analyze_Expression (R);
1264 -- If the entity is set, the node is a generic instance with a non-local
1265 -- reference to the predefined operator or to a user-defined function.
1266 -- It can also be an inequality that is expanded into the negation of a
1267 -- call to a user-defined equality operator.
1269 -- For the predefined case, the result is Boolean, regardless of the
1270 -- type of the operands. The operands may even be limited, if they are
1271 -- generic actuals. If they are overloaded, label the left argument with
1272 -- the common type that must be present, or with the type of the formal
1273 -- of the user-defined function.
1275 if Present (Entity (N)) then
1276 Op_Id := Entity (N);
1278 if Ekind (Op_Id) = E_Operator then
1279 Add_One_Interp (N, Op_Id, Standard_Boolean);
1281 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1284 if Is_Overloaded (L) then
1285 if Ekind (Op_Id) = E_Operator then
1286 Set_Etype (L, Intersect_Types (L, R));
1288 Set_Etype (L, Etype (First_Formal (Op_Id)));
1293 Op_Id := Get_Name_Entity_Id (Chars (N));
1294 while Present (Op_Id) loop
1295 if Ekind (Op_Id) = E_Operator then
1296 Find_Equality_Types (L, R, Op_Id, N);
1298 Analyze_User_Defined_Binary_Op (N, Op_Id);
1301 Op_Id := Homonym (Op_Id);
1305 -- If there was no match, and the operator is inequality, this may
1306 -- be a case where inequality has not been made explicit, as for
1307 -- tagged types. Analyze the node as the negation of an equality
1308 -- operation. This cannot be done earlier, because before analysis
1309 -- we cannot rule out the presence of an explicit inequality.
1311 if Etype (N) = Any_Type
1312 and then Nkind (N) = N_Op_Ne
1314 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1315 while Present (Op_Id) loop
1316 if Ekind (Op_Id) = E_Operator then
1317 Find_Equality_Types (L, R, Op_Id, N);
1319 Analyze_User_Defined_Binary_Op (N, Op_Id);
1322 Op_Id := Homonym (Op_Id);
1325 if Etype (N) /= Any_Type then
1326 Op_Id := Entity (N);
1332 Left_Opnd => Left_Opnd (N),
1333 Right_Opnd => Right_Opnd (N))));
1335 Set_Entity (Right_Opnd (N), Op_Id);
1341 end Analyze_Equality_Op;
1343 ----------------------------------
1344 -- Analyze_Explicit_Dereference --
1345 ----------------------------------
1347 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1348 Loc : constant Source_Ptr := Sloc (N);
1349 P : constant Node_Id := Prefix (N);
1355 function Is_Function_Type return Boolean;
1356 -- Check whether node may be interpreted as an implicit function call
1358 ----------------------
1359 -- Is_Function_Type --
1360 ----------------------
1362 function Is_Function_Type return Boolean is
1367 if not Is_Overloaded (N) then
1368 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1369 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1372 Get_First_Interp (N, I, It);
1373 while Present (It.Nam) loop
1374 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1375 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1380 Get_Next_Interp (I, It);
1385 end Is_Function_Type;
1387 -- Start of processing for Analyze_Explicit_Dereference
1391 Set_Etype (N, Any_Type);
1393 -- Test for remote access to subprogram type, and if so return
1394 -- after rewriting the original tree.
1396 if Remote_AST_E_Dereference (P) then
1400 -- Normal processing for other than remote access to subprogram type
1402 if not Is_Overloaded (P) then
1403 if Is_Access_Type (Etype (P)) then
1405 -- Set the Etype. We need to go through Is_For_Access_Subtypes to
1406 -- avoid other problems caused by the Private_Subtype and it is
1407 -- safe to go to the Base_Type because this is the same as
1408 -- converting the access value to its Base_Type.
1411 DT : Entity_Id := Designated_Type (Etype (P));
1414 if Ekind (DT) = E_Private_Subtype
1415 and then Is_For_Access_Subtype (DT)
1417 DT := Base_Type (DT);
1420 -- An explicit dereference is a legal occurrence of an
1421 -- incomplete type imported through a limited_with clause,
1422 -- if the full view is visible.
1424 if From_With_Type (DT)
1425 and then not From_With_Type (Scope (DT))
1427 (Is_Immediately_Visible (Scope (DT))
1429 (Is_Child_Unit (Scope (DT))
1430 and then Is_Visible_Child_Unit (Scope (DT))))
1432 Set_Etype (N, Available_View (DT));
1439 elsif Etype (P) /= Any_Type then
1440 Error_Msg_N ("prefix of dereference must be an access type", N);
1445 Get_First_Interp (P, I, It);
1446 while Present (It.Nam) loop
1449 if Is_Access_Type (T) then
1450 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1453 Get_Next_Interp (I, It);
1456 -- Error if no interpretation of the prefix has an access type
1458 if Etype (N) = Any_Type then
1460 ("access type required in prefix of explicit dereference", P);
1461 Set_Etype (N, Any_Type);
1467 and then Nkind (Parent (N)) /= N_Indexed_Component
1469 and then (Nkind (Parent (N)) /= N_Function_Call
1470 or else N /= Name (Parent (N)))
1472 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1473 or else N /= Name (Parent (N)))
1475 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1476 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1478 (Attribute_Name (Parent (N)) /= Name_Address
1480 Attribute_Name (Parent (N)) /= Name_Access))
1482 -- Name is a function call with no actuals, in a context that
1483 -- requires deproceduring (including as an actual in an enclosing
1484 -- function or procedure call). There are some pathological cases
1485 -- where the prefix might include functions that return access to
1486 -- subprograms and others that return a regular type. Disambiguation
1487 -- of those has to take place in Resolve.
1490 Make_Function_Call (Loc,
1491 Name => Make_Explicit_Dereference (Loc, P),
1492 Parameter_Associations => New_List);
1494 -- If the prefix is overloaded, remove operations that have formals,
1495 -- we know that this is a parameterless call.
1497 if Is_Overloaded (P) then
1498 Get_First_Interp (P, I, It);
1499 while Present (It.Nam) loop
1502 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1508 Get_Next_Interp (I, It);
1515 elsif not Is_Function_Type
1516 and then Is_Overloaded (N)
1518 -- The prefix may include access to subprograms and other access
1519 -- types. If the context selects the interpretation that is a
1520 -- function call (not a procedure call) we cannot rewrite the node
1521 -- yet, but we include the result of the call interpretation.
1523 Get_First_Interp (N, I, It);
1524 while Present (It.Nam) loop
1525 if Ekind (Base_Type (It.Typ)) = E_Subprogram_Type
1526 and then Etype (Base_Type (It.Typ)) /= Standard_Void_Type
1527 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
1529 Add_One_Interp (N, Etype (It.Typ), Etype (It.Typ));
1532 Get_Next_Interp (I, It);
1536 -- A value of remote access-to-class-wide must not be dereferenced
1539 Validate_Remote_Access_To_Class_Wide_Type (N);
1540 end Analyze_Explicit_Dereference;
1542 ------------------------
1543 -- Analyze_Expression --
1544 ------------------------
1546 procedure Analyze_Expression (N : Node_Id) is
1549 Check_Parameterless_Call (N);
1550 end Analyze_Expression;
1552 ------------------------------------
1553 -- Analyze_Indexed_Component_Form --
1554 ------------------------------------
1556 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1557 P : constant Node_Id := Prefix (N);
1558 Exprs : constant List_Id := Expressions (N);
1564 procedure Process_Function_Call;
1565 -- Prefix in indexed component form is an overloadable entity,
1566 -- so the node is a function call. Reformat it as such.
1568 procedure Process_Indexed_Component;
1569 -- Prefix in indexed component form is actually an indexed component.
1570 -- This routine processes it, knowing that the prefix is already
1573 procedure Process_Indexed_Component_Or_Slice;
1574 -- An indexed component with a single index may designate a slice if
1575 -- the index is a subtype mark. This routine disambiguates these two
1576 -- cases by resolving the prefix to see if it is a subtype mark.
1578 procedure Process_Overloaded_Indexed_Component;
1579 -- If the prefix of an indexed component is overloaded, the proper
1580 -- interpretation is selected by the index types and the context.
1582 ---------------------------
1583 -- Process_Function_Call --
1584 ---------------------------
1586 procedure Process_Function_Call is
1590 Change_Node (N, N_Function_Call);
1592 Set_Parameter_Associations (N, Exprs);
1594 -- Analyze actuals prior to analyzing the call itself
1596 Actual := First (Parameter_Associations (N));
1597 while Present (Actual) loop
1599 Check_Parameterless_Call (Actual);
1601 -- Move to next actual. Note that we use Next, not Next_Actual
1602 -- here. The reason for this is a bit subtle. If a function call
1603 -- includes named associations, the parser recognizes the node as
1604 -- a call, and it is analyzed as such. If all associations are
1605 -- positional, the parser builds an indexed_component node, and
1606 -- it is only after analysis of the prefix that the construct
1607 -- is recognized as a call, in which case Process_Function_Call
1608 -- rewrites the node and analyzes the actuals. If the list of
1609 -- actuals is malformed, the parser may leave the node as an
1610 -- indexed component (despite the presence of named associations).
1611 -- The iterator Next_Actual is equivalent to Next if the list is
1612 -- positional, but follows the normalized chain of actuals when
1613 -- named associations are present. In this case normalization has
1614 -- not taken place, and actuals remain unanalyzed, which leads to
1615 -- subsequent crashes or loops if there is an attempt to continue
1616 -- analysis of the program.
1622 end Process_Function_Call;
1624 -------------------------------
1625 -- Process_Indexed_Component --
1626 -------------------------------
1628 procedure Process_Indexed_Component is
1630 Array_Type : Entity_Id;
1632 Pent : Entity_Id := Empty;
1635 Exp := First (Exprs);
1637 if Is_Overloaded (P) then
1638 Process_Overloaded_Indexed_Component;
1641 Array_Type := Etype (P);
1643 if Is_Entity_Name (P) then
1645 elsif Nkind (P) = N_Selected_Component
1646 and then Is_Entity_Name (Selector_Name (P))
1648 Pent := Entity (Selector_Name (P));
1651 -- Prefix must be appropriate for an array type, taking into
1652 -- account a possible implicit dereference.
1654 if Is_Access_Type (Array_Type) then
1655 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1656 Array_Type := Process_Implicit_Dereference_Prefix (Pent, P);
1659 if Is_Array_Type (Array_Type) then
1662 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1664 Set_Etype (N, Any_Type);
1666 if not Has_Compatible_Type
1667 (Exp, Entry_Index_Type (Pent))
1669 Error_Msg_N ("invalid index type in entry name", N);
1671 elsif Present (Next (Exp)) then
1672 Error_Msg_N ("too many subscripts in entry reference", N);
1675 Set_Etype (N, Etype (P));
1680 elsif Is_Record_Type (Array_Type)
1681 and then Remote_AST_I_Dereference (P)
1685 elsif Array_Type = Any_Type then
1686 Set_Etype (N, Any_Type);
1689 -- Here we definitely have a bad indexing
1692 if Nkind (Parent (N)) = N_Requeue_Statement
1693 and then Present (Pent) and then Ekind (Pent) = E_Entry
1696 ("REQUEUE does not permit parameters", First (Exprs));
1698 elsif Is_Entity_Name (P)
1699 and then Etype (P) = Standard_Void_Type
1701 Error_Msg_NE ("incorrect use of&", P, Entity (P));
1704 Error_Msg_N ("array type required in indexed component", P);
1707 Set_Etype (N, Any_Type);
1711 Index := First_Index (Array_Type);
1712 while Present (Index) and then Present (Exp) loop
1713 if not Has_Compatible_Type (Exp, Etype (Index)) then
1714 Wrong_Type (Exp, Etype (Index));
1715 Set_Etype (N, Any_Type);
1723 Set_Etype (N, Component_Type (Array_Type));
1725 if Present (Index) then
1727 ("too few subscripts in array reference", First (Exprs));
1729 elsif Present (Exp) then
1730 Error_Msg_N ("too many subscripts in array reference", Exp);
1733 end Process_Indexed_Component;
1735 ----------------------------------------
1736 -- Process_Indexed_Component_Or_Slice --
1737 ----------------------------------------
1739 procedure Process_Indexed_Component_Or_Slice is
1741 Exp := First (Exprs);
1742 while Present (Exp) loop
1743 Analyze_Expression (Exp);
1747 Exp := First (Exprs);
1749 -- If one index is present, and it is a subtype name, then the
1750 -- node denotes a slice (note that the case of an explicit range
1751 -- for a slice was already built as an N_Slice node in the first
1752 -- place, so that case is not handled here).
1754 -- We use a replace rather than a rewrite here because this is one
1755 -- of the cases in which the tree built by the parser is plain wrong.
1758 and then Is_Entity_Name (Exp)
1759 and then Is_Type (Entity (Exp))
1762 Make_Slice (Sloc (N),
1764 Discrete_Range => New_Copy (Exp)));
1767 -- Otherwise (more than one index present, or single index is not
1768 -- a subtype name), then we have the indexed component case.
1771 Process_Indexed_Component;
1773 end Process_Indexed_Component_Or_Slice;
1775 ------------------------------------------
1776 -- Process_Overloaded_Indexed_Component --
1777 ------------------------------------------
1779 procedure Process_Overloaded_Indexed_Component is
1788 Set_Etype (N, Any_Type);
1790 Get_First_Interp (P, I, It);
1791 while Present (It.Nam) loop
1794 if Is_Access_Type (Typ) then
1795 Typ := Designated_Type (Typ);
1796 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1799 if Is_Array_Type (Typ) then
1801 -- Got a candidate: verify that index types are compatible
1803 Index := First_Index (Typ);
1805 Exp := First (Exprs);
1806 while Present (Index) and then Present (Exp) loop
1807 if Has_Compatible_Type (Exp, Etype (Index)) then
1819 if Found and then No (Index) and then No (Exp) then
1821 Etype (Component_Type (Typ)),
1822 Etype (Component_Type (Typ)));
1826 Get_Next_Interp (I, It);
1829 if Etype (N) = Any_Type then
1830 Error_Msg_N ("no legal interpretation for indexed component", N);
1831 Set_Is_Overloaded (N, False);
1835 end Process_Overloaded_Indexed_Component;
1837 -- Start of processing for Analyze_Indexed_Component_Form
1840 -- Get name of array, function or type
1844 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement) then
1846 -- If P is an explicit dereference whose prefix is of a
1847 -- remote access-to-subprogram type, then N has already
1848 -- been rewritten as a subprogram call and analyzed.
1853 pragma Assert (Nkind (N) = N_Indexed_Component);
1855 P_T := Base_Type (Etype (P));
1857 if Is_Entity_Name (P)
1858 or else Nkind (P) = N_Operator_Symbol
1862 if Is_Type (U_N) then
1864 -- Reformat node as a type conversion
1866 E := Remove_Head (Exprs);
1868 if Present (First (Exprs)) then
1870 ("argument of type conversion must be single expression", N);
1873 Change_Node (N, N_Type_Conversion);
1874 Set_Subtype_Mark (N, P);
1876 Set_Expression (N, E);
1878 -- After changing the node, call for the specific Analysis
1879 -- routine directly, to avoid a double call to the expander.
1881 Analyze_Type_Conversion (N);
1885 if Is_Overloadable (U_N) then
1886 Process_Function_Call;
1888 elsif Ekind (Etype (P)) = E_Subprogram_Type
1889 or else (Is_Access_Type (Etype (P))
1891 Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type)
1893 -- Call to access_to-subprogram with possible implicit dereference
1895 Process_Function_Call;
1897 elsif Is_Generic_Subprogram (U_N) then
1899 -- A common beginner's (or C++ templates fan) error
1901 Error_Msg_N ("generic subprogram cannot be called", N);
1902 Set_Etype (N, Any_Type);
1906 Process_Indexed_Component_Or_Slice;
1909 -- If not an entity name, prefix is an expression that may denote
1910 -- an array or an access-to-subprogram.
1913 if Ekind (P_T) = E_Subprogram_Type
1914 or else (Is_Access_Type (P_T)
1916 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
1918 Process_Function_Call;
1920 elsif Nkind (P) = N_Selected_Component
1921 and then Is_Overloadable (Entity (Selector_Name (P)))
1923 Process_Function_Call;
1926 -- Indexed component, slice, or a call to a member of a family
1927 -- entry, which will be converted to an entry call later.
1929 Process_Indexed_Component_Or_Slice;
1932 end Analyze_Indexed_Component_Form;
1934 ------------------------
1935 -- Analyze_Logical_Op --
1936 ------------------------
1938 procedure Analyze_Logical_Op (N : Node_Id) is
1939 L : constant Node_Id := Left_Opnd (N);
1940 R : constant Node_Id := Right_Opnd (N);
1941 Op_Id : Entity_Id := Entity (N);
1944 Set_Etype (N, Any_Type);
1945 Candidate_Type := Empty;
1947 Analyze_Expression (L);
1948 Analyze_Expression (R);
1950 if Present (Op_Id) then
1952 if Ekind (Op_Id) = E_Operator then
1953 Find_Boolean_Types (L, R, Op_Id, N);
1955 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1959 Op_Id := Get_Name_Entity_Id (Chars (N));
1960 while Present (Op_Id) loop
1961 if Ekind (Op_Id) = E_Operator then
1962 Find_Boolean_Types (L, R, Op_Id, N);
1964 Analyze_User_Defined_Binary_Op (N, Op_Id);
1967 Op_Id := Homonym (Op_Id);
1972 end Analyze_Logical_Op;
1974 ---------------------------
1975 -- Analyze_Membership_Op --
1976 ---------------------------
1978 procedure Analyze_Membership_Op (N : Node_Id) is
1979 L : constant Node_Id := Left_Opnd (N);
1980 R : constant Node_Id := Right_Opnd (N);
1982 Index : Interp_Index;
1984 Found : Boolean := False;
1988 procedure Try_One_Interp (T1 : Entity_Id);
1989 -- Routine to try one proposed interpretation. Note that the context
1990 -- of the operation plays no role in resolving the arguments, so that
1991 -- if there is more than one interpretation of the operands that is
1992 -- compatible with a membership test, the operation is ambiguous.
1994 --------------------
1995 -- Try_One_Interp --
1996 --------------------
1998 procedure Try_One_Interp (T1 : Entity_Id) is
2000 if Has_Compatible_Type (R, T1) then
2002 and then Base_Type (T1) /= Base_Type (T_F)
2004 It := Disambiguate (L, I_F, Index, Any_Type);
2006 if It = No_Interp then
2007 Ambiguous_Operands (N);
2008 Set_Etype (L, Any_Type);
2026 -- Start of processing for Analyze_Membership_Op
2029 Analyze_Expression (L);
2031 if Nkind (R) = N_Range
2032 or else (Nkind (R) = N_Attribute_Reference
2033 and then Attribute_Name (R) = Name_Range)
2037 if not Is_Overloaded (L) then
2038 Try_One_Interp (Etype (L));
2041 Get_First_Interp (L, Index, It);
2042 while Present (It.Typ) loop
2043 Try_One_Interp (It.Typ);
2044 Get_Next_Interp (Index, It);
2048 -- If not a range, it can only be a subtype mark, or else there
2049 -- is a more basic error, to be diagnosed in Find_Type.
2054 if Is_Entity_Name (R) then
2055 Check_Fully_Declared (Entity (R), R);
2059 -- Compatibility between expression and subtype mark or range is
2060 -- checked during resolution. The result of the operation is Boolean
2063 Set_Etype (N, Standard_Boolean);
2065 if Comes_From_Source (N)
2066 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2068 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2070 end Analyze_Membership_Op;
2072 ----------------------
2073 -- Analyze_Negation --
2074 ----------------------
2076 procedure Analyze_Negation (N : Node_Id) is
2077 R : constant Node_Id := Right_Opnd (N);
2078 Op_Id : Entity_Id := Entity (N);
2081 Set_Etype (N, Any_Type);
2082 Candidate_Type := Empty;
2084 Analyze_Expression (R);
2086 if Present (Op_Id) then
2087 if Ekind (Op_Id) = E_Operator then
2088 Find_Negation_Types (R, Op_Id, N);
2090 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2094 Op_Id := Get_Name_Entity_Id (Chars (N));
2095 while Present (Op_Id) loop
2096 if Ekind (Op_Id) = E_Operator then
2097 Find_Negation_Types (R, Op_Id, N);
2099 Analyze_User_Defined_Unary_Op (N, Op_Id);
2102 Op_Id := Homonym (Op_Id);
2107 end Analyze_Negation;
2113 procedure Analyze_Null (N : Node_Id) is
2115 Set_Etype (N, Any_Access);
2118 ----------------------
2119 -- Analyze_One_Call --
2120 ----------------------
2122 procedure Analyze_One_Call
2126 Success : out Boolean;
2127 Skip_First : Boolean := False)
2129 Actuals : constant List_Id := Parameter_Associations (N);
2130 Prev_T : constant Entity_Id := Etype (N);
2132 Must_Skip : constant Boolean := Skip_First
2133 or else Nkind (Original_Node (N)) = N_Selected_Component
2135 (Nkind (Original_Node (N)) = N_Indexed_Component
2136 and then Nkind (Prefix (Original_Node (N)))
2137 = N_Selected_Component);
2138 -- The first formal must be omitted from the match when trying to find
2139 -- a primitive operation that is a possible interpretation, and also
2140 -- after the call has been rewritten, because the corresponding actual
2141 -- is already known to be compatible, and because this may be an
2142 -- indexing of a call with default parameters.
2146 Is_Indexed : Boolean := False;
2147 Is_Indirect : Boolean := False;
2148 Subp_Type : constant Entity_Id := Etype (Nam);
2151 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2152 -- There may be a user-defined operator that hides the current
2153 -- interpretation. We must check for this independently of the
2154 -- analysis of the call with the user-defined operation, because
2155 -- the parameter names may be wrong and yet the hiding takes place.
2156 -- This fixes a problem with ACATS test B34014O.
2158 -- When the type Address is a visible integer type, and the DEC
2159 -- system extension is visible, the predefined operator may be
2160 -- hidden as well, by one of the address operations in auxdec.
2161 -- Finally, The abstract operations on address do not hide the
2162 -- predefined operator (this is the purpose of making them abstract).
2164 procedure Indicate_Name_And_Type;
2165 -- If candidate interpretation matches, indicate name and type of
2166 -- result on call node.
2168 ----------------------------
2169 -- Indicate_Name_And_Type --
2170 ----------------------------
2172 procedure Indicate_Name_And_Type is
2174 Add_One_Interp (N, Nam, Etype (Nam));
2177 -- If the prefix of the call is a name, indicate the entity
2178 -- being called. If it is not a name, it is an expression that
2179 -- denotes an access to subprogram or else an entry or family. In
2180 -- the latter case, the name is a selected component, and the entity
2181 -- being called is noted on the selector.
2183 if not Is_Type (Nam) then
2184 if Is_Entity_Name (Name (N))
2185 or else Nkind (Name (N)) = N_Operator_Symbol
2187 Set_Entity (Name (N), Nam);
2189 elsif Nkind (Name (N)) = N_Selected_Component then
2190 Set_Entity (Selector_Name (Name (N)), Nam);
2194 if Debug_Flag_E and not Report then
2195 Write_Str (" Overloaded call ");
2196 Write_Int (Int (N));
2197 Write_Str (" compatible with ");
2198 Write_Int (Int (Nam));
2201 end Indicate_Name_And_Type;
2203 ------------------------
2204 -- Operator_Hidden_By --
2205 ------------------------
2207 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2208 Act1 : constant Node_Id := First_Actual (N);
2209 Act2 : constant Node_Id := Next_Actual (Act1);
2210 Form1 : constant Entity_Id := First_Formal (Fun);
2211 Form2 : constant Entity_Id := Next_Formal (Form1);
2214 if Ekind (Fun) /= E_Function
2215 or else Is_Abstract_Subprogram (Fun)
2219 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2222 elsif Present (Form2) then
2224 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2229 elsif Present (Act2) then
2233 -- Now we know that the arity of the operator matches the function,
2234 -- and the function call is a valid interpretation. The function
2235 -- hides the operator if it has the right signature, or if one of
2236 -- its operands is a non-abstract operation on Address when this is
2237 -- a visible integer type.
2239 return Hides_Op (Fun, Nam)
2240 or else Is_Descendent_Of_Address (Etype (Form1))
2243 and then Is_Descendent_Of_Address (Etype (Form2)));
2244 end Operator_Hidden_By;
2246 -- Start of processing for Analyze_One_Call
2251 -- If the subprogram has no formals or if all the formals have defaults,
2252 -- and the return type is an array type, the node may denote an indexing
2253 -- of the result of a parameterless call. In Ada 2005, the subprogram
2254 -- may have one non-defaulted formal, and the call may have been written
2255 -- in prefix notation, so that the rebuilt parameter list has more than
2258 if not Is_Overloadable (Nam)
2259 and then Ekind (Nam) /= E_Subprogram_Type
2260 and then Ekind (Nam) /= E_Entry_Family
2265 -- An indexing requires at least one actual
2267 if not Is_Empty_List (Actuals)
2269 (Needs_No_Actuals (Nam)
2271 (Needs_One_Actual (Nam)
2272 and then Present (Next_Actual (First (Actuals)))))
2274 if Is_Array_Type (Subp_Type) then
2275 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2277 elsif Is_Access_Type (Subp_Type)
2278 and then Is_Array_Type (Designated_Type (Subp_Type))
2282 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2284 -- The prefix can also be a parameterless function that returns an
2285 -- access to subprogram, in which case this is an indirect call.
2286 -- If this succeeds, an explicit dereference is added later on,
2287 -- in Analyze_Call or Resolve_Call.
2289 elsif Is_Access_Type (Subp_Type)
2290 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2292 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2297 -- If the call has been transformed into a slice, it is of the form
2298 -- F (Subtype) where F is parameterless. The node has been rewritten in
2299 -- Try_Indexed_Call and there is nothing else to do.
2302 and then Nkind (N) = N_Slice
2308 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2312 -- If an indirect call is a possible interpretation, indicate
2313 -- success to the caller.
2319 -- Mismatch in number or names of parameters
2321 elsif Debug_Flag_E then
2322 Write_Str (" normalization fails in call ");
2323 Write_Int (Int (N));
2324 Write_Str (" with subprogram ");
2325 Write_Int (Int (Nam));
2329 -- If the context expects a function call, discard any interpretation
2330 -- that is a procedure. If the node is not overloaded, leave as is for
2331 -- better error reporting when type mismatch is found.
2333 elsif Nkind (N) = N_Function_Call
2334 and then Is_Overloaded (Name (N))
2335 and then Ekind (Nam) = E_Procedure
2339 -- Ditto for function calls in a procedure context
2341 elsif Nkind (N) = N_Procedure_Call_Statement
2342 and then Is_Overloaded (Name (N))
2343 and then Etype (Nam) /= Standard_Void_Type
2347 elsif No (Actuals) then
2349 -- If Normalize succeeds, then there are default parameters for
2352 Indicate_Name_And_Type;
2354 elsif Ekind (Nam) = E_Operator then
2355 if Nkind (N) = N_Procedure_Call_Statement then
2359 -- This can occur when the prefix of the call is an operator
2360 -- name or an expanded name whose selector is an operator name.
2362 Analyze_Operator_Call (N, Nam);
2364 if Etype (N) /= Prev_T then
2366 -- Check that operator is not hidden by a function interpretation
2368 if Is_Overloaded (Name (N)) then
2374 Get_First_Interp (Name (N), I, It);
2375 while Present (It.Nam) loop
2376 if Operator_Hidden_By (It.Nam) then
2377 Set_Etype (N, Prev_T);
2381 Get_Next_Interp (I, It);
2386 -- If operator matches formals, record its name on the call.
2387 -- If the operator is overloaded, Resolve will select the
2388 -- correct one from the list of interpretations. The call
2389 -- node itself carries the first candidate.
2391 Set_Entity (Name (N), Nam);
2394 elsif Report and then Etype (N) = Any_Type then
2395 Error_Msg_N ("incompatible arguments for operator", N);
2399 -- Normalize_Actuals has chained the named associations in the
2400 -- correct order of the formals.
2402 Actual := First_Actual (N);
2403 Formal := First_Formal (Nam);
2405 -- If we are analyzing a call rewritten from object notation,
2406 -- skip first actual, which may be rewritten later as an
2407 -- explicit dereference.
2410 Next_Actual (Actual);
2411 Next_Formal (Formal);
2414 while Present (Actual) and then Present (Formal) loop
2415 if Nkind (Parent (Actual)) /= N_Parameter_Association
2416 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2418 -- The actual can be compatible with the formal, but we must
2419 -- also check that the context is not an address type that is
2420 -- visibly an integer type, as is the case in VMS_64. In this
2421 -- case the use of literals is illegal, except in the body of
2422 -- descendents of system, where arithmetic operations on
2423 -- address are of course used.
2425 if Has_Compatible_Type (Actual, Etype (Formal))
2427 (Etype (Actual) /= Universal_Integer
2428 or else not Is_Descendent_Of_Address (Etype (Formal))
2430 Is_Predefined_File_Name
2431 (Unit_File_Name (Get_Source_Unit (N))))
2433 Next_Actual (Actual);
2434 Next_Formal (Formal);
2437 if Debug_Flag_E then
2438 Write_Str (" type checking fails in call ");
2439 Write_Int (Int (N));
2440 Write_Str (" with formal ");
2441 Write_Int (Int (Formal));
2442 Write_Str (" in subprogram ");
2443 Write_Int (Int (Nam));
2447 if Report and not Is_Indexed and not Is_Indirect then
2449 -- Ada 2005 (AI-251): Complete the error notification
2450 -- to help new Ada 2005 users.
2452 if Is_Class_Wide_Type (Etype (Formal))
2453 and then Is_Interface (Etype (Etype (Formal)))
2454 and then not Interface_Present_In_Ancestor
2455 (Typ => Etype (Actual),
2456 Iface => Etype (Etype (Formal)))
2459 ("(Ada 2005) does not implement interface }",
2460 Actual, Etype (Etype (Formal)));
2463 Wrong_Type (Actual, Etype (Formal));
2465 if Nkind (Actual) = N_Op_Eq
2466 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2468 Formal := First_Formal (Nam);
2469 while Present (Formal) loop
2470 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2471 Error_Msg_N -- CODEFIX
2472 ("possible misspelling of `='>`!", Actual);
2476 Next_Formal (Formal);
2480 if All_Errors_Mode then
2481 Error_Msg_Sloc := Sloc (Nam);
2483 if Is_Overloadable (Nam)
2484 and then Present (Alias (Nam))
2485 and then not Comes_From_Source (Nam)
2488 ("\\ =='> in call to inherited operation & #!",
2491 elsif Ekind (Nam) = E_Subprogram_Type then
2493 Access_To_Subprogram_Typ :
2494 constant Entity_Id :=
2496 (Associated_Node_For_Itype (Nam));
2499 "\\ =='> in call to dereference of &#!",
2500 Actual, Access_To_Subprogram_Typ);
2505 ("\\ =='> in call to &#!", Actual, Nam);
2515 -- Normalize_Actuals has verified that a default value exists
2516 -- for this formal. Current actual names a subsequent formal.
2518 Next_Formal (Formal);
2522 -- On exit, all actuals match
2524 Indicate_Name_And_Type;
2526 end Analyze_One_Call;
2528 ---------------------------
2529 -- Analyze_Operator_Call --
2530 ---------------------------
2532 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2533 Op_Name : constant Name_Id := Chars (Op_Id);
2534 Act1 : constant Node_Id := First_Actual (N);
2535 Act2 : constant Node_Id := Next_Actual (Act1);
2538 -- Binary operator case
2540 if Present (Act2) then
2542 -- If more than two operands, then not binary operator after all
2544 if Present (Next_Actual (Act2)) then
2547 elsif Op_Name = Name_Op_Add
2548 or else Op_Name = Name_Op_Subtract
2549 or else Op_Name = Name_Op_Multiply
2550 or else Op_Name = Name_Op_Divide
2551 or else Op_Name = Name_Op_Mod
2552 or else Op_Name = Name_Op_Rem
2553 or else Op_Name = Name_Op_Expon
2555 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2557 elsif Op_Name = Name_Op_And
2558 or else Op_Name = Name_Op_Or
2559 or else Op_Name = Name_Op_Xor
2561 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2563 elsif Op_Name = Name_Op_Lt
2564 or else Op_Name = Name_Op_Le
2565 or else Op_Name = Name_Op_Gt
2566 or else Op_Name = Name_Op_Ge
2568 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2570 elsif Op_Name = Name_Op_Eq
2571 or else Op_Name = Name_Op_Ne
2573 Find_Equality_Types (Act1, Act2, Op_Id, N);
2575 elsif Op_Name = Name_Op_Concat then
2576 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2578 -- Is this else null correct, or should it be an abort???
2584 -- Unary operator case
2587 if Op_Name = Name_Op_Subtract or else
2588 Op_Name = Name_Op_Add or else
2589 Op_Name = Name_Op_Abs
2591 Find_Unary_Types (Act1, Op_Id, N);
2594 Op_Name = Name_Op_Not
2596 Find_Negation_Types (Act1, Op_Id, N);
2598 -- Is this else null correct, or should it be an abort???
2604 end Analyze_Operator_Call;
2606 -------------------------------------------
2607 -- Analyze_Overloaded_Selected_Component --
2608 -------------------------------------------
2610 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
2611 Nam : constant Node_Id := Prefix (N);
2612 Sel : constant Node_Id := Selector_Name (N);
2619 Set_Etype (Sel, Any_Type);
2621 Get_First_Interp (Nam, I, It);
2622 while Present (It.Typ) loop
2623 if Is_Access_Type (It.Typ) then
2624 T := Designated_Type (It.Typ);
2625 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2630 if Is_Record_Type (T) then
2632 -- If the prefix is a class-wide type, the visible components are
2633 -- those of the base type.
2635 if Is_Class_Wide_Type (T) then
2639 Comp := First_Entity (T);
2640 while Present (Comp) loop
2641 if Chars (Comp) = Chars (Sel)
2642 and then Is_Visible_Component (Comp)
2645 -- AI05-105: if the context is an object renaming with
2646 -- an anonymous access type, the expected type of the
2647 -- object must be anonymous. This is a name resolution rule.
2649 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
2650 or else No (Access_Definition (Parent (N)))
2651 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
2653 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
2655 Set_Entity (Sel, Comp);
2656 Set_Etype (Sel, Etype (Comp));
2657 Add_One_Interp (N, Etype (Comp), Etype (Comp));
2659 -- This also specifies a candidate to resolve the name.
2660 -- Further overloading will be resolved from context.
2661 -- The selector name itself does not carry overloading
2664 Set_Etype (Nam, It.Typ);
2667 -- Named access type in the context of a renaming
2668 -- declaration with an access definition. Remove
2669 -- inapplicable candidate.
2678 elsif Is_Concurrent_Type (T) then
2679 Comp := First_Entity (T);
2680 while Present (Comp)
2681 and then Comp /= First_Private_Entity (T)
2683 if Chars (Comp) = Chars (Sel) then
2684 if Is_Overloadable (Comp) then
2685 Add_One_Interp (Sel, Comp, Etype (Comp));
2687 Set_Entity_With_Style_Check (Sel, Comp);
2688 Generate_Reference (Comp, Sel);
2691 Set_Etype (Sel, Etype (Comp));
2692 Set_Etype (N, Etype (Comp));
2693 Set_Etype (Nam, It.Typ);
2695 -- For access type case, introduce explicit deference for
2696 -- more uniform treatment of entry calls. Do this only
2697 -- once if several interpretations yield an access type.
2699 if Is_Access_Type (Etype (Nam))
2700 and then Nkind (Nam) /= N_Explicit_Dereference
2702 Insert_Explicit_Dereference (Nam);
2704 (Warn_On_Dereference, "?implicit dereference", N);
2711 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2714 Get_Next_Interp (I, It);
2717 if Etype (N) = Any_Type
2718 and then not Try_Object_Operation (N)
2720 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
2721 Set_Entity (Sel, Any_Id);
2722 Set_Etype (Sel, Any_Type);
2724 end Analyze_Overloaded_Selected_Component;
2726 ----------------------------------
2727 -- Analyze_Qualified_Expression --
2728 ----------------------------------
2730 procedure Analyze_Qualified_Expression (N : Node_Id) is
2731 Mark : constant Entity_Id := Subtype_Mark (N);
2732 Expr : constant Node_Id := Expression (N);
2738 Analyze_Expression (Expr);
2740 Set_Etype (N, Any_Type);
2745 if T = Any_Type then
2749 Check_Fully_Declared (T, N);
2751 -- If expected type is class-wide, check for exact match before
2752 -- expansion, because if the expression is a dispatching call it
2753 -- may be rewritten as explicit dereference with class-wide result.
2754 -- If expression is overloaded, retain only interpretations that
2755 -- will yield exact matches.
2757 if Is_Class_Wide_Type (T) then
2758 if not Is_Overloaded (Expr) then
2759 if Base_Type (Etype (Expr)) /= Base_Type (T) then
2760 if Nkind (Expr) = N_Aggregate then
2761 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
2763 Wrong_Type (Expr, T);
2768 Get_First_Interp (Expr, I, It);
2770 while Present (It.Nam) loop
2771 if Base_Type (It.Typ) /= Base_Type (T) then
2775 Get_Next_Interp (I, It);
2781 end Analyze_Qualified_Expression;
2787 procedure Analyze_Range (N : Node_Id) is
2788 L : constant Node_Id := Low_Bound (N);
2789 H : constant Node_Id := High_Bound (N);
2790 I1, I2 : Interp_Index;
2793 procedure Check_Common_Type (T1, T2 : Entity_Id);
2794 -- Verify the compatibility of two types, and choose the
2795 -- non universal one if the other is universal.
2797 procedure Check_High_Bound (T : Entity_Id);
2798 -- Test one interpretation of the low bound against all those
2799 -- of the high bound.
2801 procedure Check_Universal_Expression (N : Node_Id);
2802 -- In Ada83, reject bounds of a universal range that are not
2803 -- literals or entity names.
2805 -----------------------
2806 -- Check_Common_Type --
2807 -----------------------
2809 procedure Check_Common_Type (T1, T2 : Entity_Id) is
2811 if Covers (T1 => T1, T2 => T2)
2813 Covers (T1 => T2, T2 => T1)
2815 if T1 = Universal_Integer
2816 or else T1 = Universal_Real
2817 or else T1 = Any_Character
2819 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
2822 Add_One_Interp (N, T1, T1);
2825 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
2828 end Check_Common_Type;
2830 ----------------------
2831 -- Check_High_Bound --
2832 ----------------------
2834 procedure Check_High_Bound (T : Entity_Id) is
2836 if not Is_Overloaded (H) then
2837 Check_Common_Type (T, Etype (H));
2839 Get_First_Interp (H, I2, It2);
2840 while Present (It2.Typ) loop
2841 Check_Common_Type (T, It2.Typ);
2842 Get_Next_Interp (I2, It2);
2845 end Check_High_Bound;
2847 -----------------------------
2848 -- Is_Universal_Expression --
2849 -----------------------------
2851 procedure Check_Universal_Expression (N : Node_Id) is
2853 if Etype (N) = Universal_Integer
2854 and then Nkind (N) /= N_Integer_Literal
2855 and then not Is_Entity_Name (N)
2856 and then Nkind (N) /= N_Attribute_Reference
2858 Error_Msg_N ("illegal bound in discrete range", N);
2860 end Check_Universal_Expression;
2862 -- Start of processing for Analyze_Range
2865 Set_Etype (N, Any_Type);
2866 Analyze_Expression (L);
2867 Analyze_Expression (H);
2869 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
2873 if not Is_Overloaded (L) then
2874 Check_High_Bound (Etype (L));
2876 Get_First_Interp (L, I1, It1);
2877 while Present (It1.Typ) loop
2878 Check_High_Bound (It1.Typ);
2879 Get_Next_Interp (I1, It1);
2883 -- If result is Any_Type, then we did not find a compatible pair
2885 if Etype (N) = Any_Type then
2886 Error_Msg_N ("incompatible types in range ", N);
2890 if Ada_Version = Ada_83
2892 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
2893 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
2895 Check_Universal_Expression (L);
2896 Check_Universal_Expression (H);
2900 -----------------------
2901 -- Analyze_Reference --
2902 -----------------------
2904 procedure Analyze_Reference (N : Node_Id) is
2905 P : constant Node_Id := Prefix (N);
2908 Acc_Type : Entity_Id;
2913 -- An interesting error check, if we take the 'Reference of an object
2914 -- for which a pragma Atomic or Volatile has been given, and the type
2915 -- of the object is not Atomic or Volatile, then we are in trouble. The
2916 -- problem is that no trace of the atomic/volatile status will remain
2917 -- for the backend to respect when it deals with the resulting pointer,
2918 -- since the pointer type will not be marked atomic (it is a pointer to
2919 -- the base type of the object).
2921 -- It is not clear if that can ever occur, but in case it does, we will
2922 -- generate an error message. Not clear if this message can ever be
2923 -- generated, and pretty clear that it represents a bug if it is, still
2924 -- seems worth checking!
2928 if Is_Entity_Name (P)
2929 and then Is_Object_Reference (P)
2934 if (Has_Atomic_Components (E)
2935 and then not Has_Atomic_Components (T))
2937 (Has_Volatile_Components (E)
2938 and then not Has_Volatile_Components (T))
2939 or else (Is_Atomic (E) and then not Is_Atomic (T))
2940 or else (Is_Volatile (E) and then not Is_Volatile (T))
2942 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
2946 -- Carry on with normal processing
2948 Acc_Type := Create_Itype (E_Allocator_Type, N);
2949 Set_Etype (Acc_Type, Acc_Type);
2950 Set_Directly_Designated_Type (Acc_Type, Etype (P));
2951 Set_Etype (N, Acc_Type);
2952 end Analyze_Reference;
2954 --------------------------------
2955 -- Analyze_Selected_Component --
2956 --------------------------------
2958 -- Prefix is a record type or a task or protected type. In the
2959 -- later case, the selector must denote a visible entry.
2961 procedure Analyze_Selected_Component (N : Node_Id) is
2962 Name : constant Node_Id := Prefix (N);
2963 Sel : constant Node_Id := Selector_Name (N);
2966 Has_Candidate : Boolean := False;
2969 Pent : Entity_Id := Empty;
2970 Prefix_Type : Entity_Id;
2972 Type_To_Use : Entity_Id;
2973 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
2974 -- a class-wide type, we use its root type, whose components are
2975 -- present in the class-wide type.
2977 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
2978 -- It is known that the parent of N denotes a subprogram call. Comp
2979 -- is an overloadable component of the concurrent type of the prefix.
2980 -- Determine whether all formals of the parent of N and Comp are mode
2981 -- conformant. If the parent node is not analyzed yet it may be an
2982 -- indexed component rather than a function call.
2984 ------------------------------
2985 -- Has_Mode_Conformant_Spec --
2986 ------------------------------
2988 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
2989 Comp_Param : Entity_Id;
2991 Param_Typ : Entity_Id;
2994 Comp_Param := First_Formal (Comp);
2996 if Nkind (Parent (N)) = N_Indexed_Component then
2997 Param := First (Expressions (Parent (N)));
2999 Param := First (Parameter_Associations (Parent (N)));
3002 while Present (Comp_Param)
3003 and then Present (Param)
3005 Param_Typ := Find_Parameter_Type (Param);
3007 if Present (Param_Typ)
3009 not Conforming_Types
3010 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3015 Next_Formal (Comp_Param);
3019 -- One of the specs has additional formals
3021 if Present (Comp_Param) or else Present (Param) then
3026 end Has_Mode_Conformant_Spec;
3028 -- Start of processing for Analyze_Selected_Component
3031 Set_Etype (N, Any_Type);
3033 if Is_Overloaded (Name) then
3034 Analyze_Overloaded_Selected_Component (N);
3037 elsif Etype (Name) = Any_Type then
3038 Set_Entity (Sel, Any_Id);
3039 Set_Etype (Sel, Any_Type);
3043 Prefix_Type := Etype (Name);
3046 if Is_Access_Type (Prefix_Type) then
3048 -- A RACW object can never be used as prefix of a selected
3049 -- component since that means it is dereferenced without
3050 -- being a controlling operand of a dispatching operation
3051 -- (RM E.2.2(16/1)). Before reporting an error, we must check
3052 -- whether this is actually a dispatching call in prefix form.
3054 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3055 and then Comes_From_Source (N)
3057 if Try_Object_Operation (N) then
3061 ("invalid dereference of a remote access-to-class-wide value",
3065 -- Normal case of selected component applied to access type
3068 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3070 if Is_Entity_Name (Name) then
3071 Pent := Entity (Name);
3072 elsif Nkind (Name) = N_Selected_Component
3073 and then Is_Entity_Name (Selector_Name (Name))
3075 Pent := Entity (Selector_Name (Name));
3078 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3081 -- If we have an explicit dereference of a remote access-to-class-wide
3082 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3083 -- have to check for the case of a prefix that is a controlling operand
3084 -- of a prefixed dispatching call, as the dereference is legal in that
3085 -- case. Normally this condition is checked in Validate_Remote_Access_
3086 -- To_Class_Wide_Type, but we have to defer the checking for selected
3087 -- component prefixes because of the prefixed dispatching call case.
3088 -- Note that implicit dereferences are checked for this just above.
3090 elsif Nkind (Name) = N_Explicit_Dereference
3091 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3092 and then Comes_From_Source (N)
3094 if Try_Object_Operation (N) then
3098 ("invalid dereference of a remote access-to-class-wide value",
3103 -- (Ada 2005): if the prefix is the limited view of a type, and
3104 -- the context already includes the full view, use the full view
3105 -- in what follows, either to retrieve a component of to find
3106 -- a primitive operation. If the prefix is an explicit dereference,
3107 -- set the type of the prefix to reflect this transformation.
3108 -- If the non-limited view is itself an incomplete type, get the
3109 -- full view if available.
3111 if Is_Incomplete_Type (Prefix_Type)
3112 and then From_With_Type (Prefix_Type)
3113 and then Present (Non_Limited_View (Prefix_Type))
3115 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3117 if Nkind (N) = N_Explicit_Dereference then
3118 Set_Etype (Prefix (N), Prefix_Type);
3121 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3122 and then From_With_Type (Prefix_Type)
3123 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3126 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3128 if Nkind (N) = N_Explicit_Dereference then
3129 Set_Etype (Prefix (N), Prefix_Type);
3133 if Ekind (Prefix_Type) = E_Private_Subtype then
3134 Prefix_Type := Base_Type (Prefix_Type);
3137 Type_To_Use := Prefix_Type;
3139 -- For class-wide types, use the entity list of the root type. This
3140 -- indirection is specially important for private extensions because
3141 -- only the root type get switched (not the class-wide type).
3143 if Is_Class_Wide_Type (Prefix_Type) then
3144 Type_To_Use := Root_Type (Prefix_Type);
3147 Comp := First_Entity (Type_To_Use);
3149 -- If the selector has an original discriminant, the node appears in
3150 -- an instance. Replace the discriminant with the corresponding one
3151 -- in the current discriminated type. For nested generics, this must
3152 -- be done transitively, so note the new original discriminant.
3154 if Nkind (Sel) = N_Identifier
3155 and then Present (Original_Discriminant (Sel))
3157 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3159 -- Mark entity before rewriting, for completeness and because
3160 -- subsequent semantic checks might examine the original node.
3162 Set_Entity (Sel, Comp);
3163 Rewrite (Selector_Name (N),
3164 New_Occurrence_Of (Comp, Sloc (N)));
3165 Set_Original_Discriminant (Selector_Name (N), Comp);
3166 Set_Etype (N, Etype (Comp));
3168 if Is_Access_Type (Etype (Name)) then
3169 Insert_Explicit_Dereference (Name);
3170 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3173 elsif Is_Record_Type (Prefix_Type) then
3175 -- Find component with given name
3177 while Present (Comp) loop
3178 if Chars (Comp) = Chars (Sel)
3179 and then Is_Visible_Component (Comp)
3181 Set_Entity_With_Style_Check (Sel, Comp);
3182 Set_Etype (Sel, Etype (Comp));
3184 if Ekind (Comp) = E_Discriminant then
3185 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3187 ("cannot reference discriminant of Unchecked_Union",
3191 if Is_Generic_Type (Prefix_Type)
3193 Is_Generic_Type (Root_Type (Prefix_Type))
3195 Set_Original_Discriminant (Sel, Comp);
3199 -- Resolve the prefix early otherwise it is not possible to
3200 -- build the actual subtype of the component: it may need
3201 -- to duplicate this prefix and duplication is only allowed
3202 -- on fully resolved expressions.
3206 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3207 -- subtypes in a package specification.
3210 -- limited with Pkg;
3212 -- type Acc_Inc is access Pkg.T;
3214 -- N : Natural := X.all.Comp; -- ERROR, limited view
3215 -- end Pkg; -- Comp is not visible
3217 if Nkind (Name) = N_Explicit_Dereference
3218 and then From_With_Type (Etype (Prefix (Name)))
3219 and then not Is_Potentially_Use_Visible (Etype (Name))
3220 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3221 N_Package_Specification
3224 ("premature usage of incomplete}", Prefix (Name),
3225 Etype (Prefix (Name)));
3228 -- We never need an actual subtype for the case of a selection
3229 -- for a indexed component of a non-packed array, since in
3230 -- this case gigi generates all the checks and can find the
3231 -- necessary bounds information.
3233 -- We also do not need an actual subtype for the case of
3234 -- a first, last, length, or range attribute applied to a
3235 -- non-packed array, since gigi can again get the bounds in
3236 -- these cases (gigi cannot handle the packed case, since it
3237 -- has the bounds of the packed array type, not the original
3238 -- bounds of the type). However, if the prefix is itself a
3239 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3240 -- as a dynamic-sized temporary, so we do generate an actual
3241 -- subtype for this case.
3243 Parent_N := Parent (N);
3245 if not Is_Packed (Etype (Comp))
3247 ((Nkind (Parent_N) = N_Indexed_Component
3248 and then Nkind (Name) /= N_Selected_Component)
3250 (Nkind (Parent_N) = N_Attribute_Reference
3251 and then (Attribute_Name (Parent_N) = Name_First
3253 Attribute_Name (Parent_N) = Name_Last
3255 Attribute_Name (Parent_N) = Name_Length
3257 Attribute_Name (Parent_N) = Name_Range)))
3259 Set_Etype (N, Etype (Comp));
3261 -- If full analysis is not enabled, we do not generate an
3262 -- actual subtype, because in the absence of expansion
3263 -- reference to a formal of a protected type, for example,
3264 -- will not be properly transformed, and will lead to
3265 -- out-of-scope references in gigi.
3267 -- In all other cases, we currently build an actual subtype.
3268 -- It seems likely that many of these cases can be avoided,
3269 -- but right now, the front end makes direct references to the
3270 -- bounds (e.g. in generating a length check), and if we do
3271 -- not make an actual subtype, we end up getting a direct
3272 -- reference to a discriminant, which will not do.
3274 elsif Full_Analysis then
3276 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3277 Insert_Action (N, Act_Decl);
3279 if No (Act_Decl) then
3280 Set_Etype (N, Etype (Comp));
3283 -- Component type depends on discriminants. Enter the
3284 -- main attributes of the subtype.
3287 Subt : constant Entity_Id :=
3288 Defining_Identifier (Act_Decl);
3291 Set_Etype (Subt, Base_Type (Etype (Comp)));
3292 Set_Ekind (Subt, Ekind (Etype (Comp)));
3293 Set_Etype (N, Subt);
3297 -- If Full_Analysis not enabled, just set the Etype
3300 Set_Etype (N, Etype (Comp));
3306 -- If the prefix is a private extension, check only the visible
3307 -- components of the partial view. This must include the tag,
3308 -- which can appear in expanded code in a tag check.
3310 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3311 and then Chars (Selector_Name (N)) /= Name_uTag
3313 exit when Comp = Last_Entity (Type_To_Use);
3319 -- Ada 2005 (AI-252): The selected component can be interpreted as
3320 -- a prefixed view of a subprogram. Depending on the context, this is
3321 -- either a name that can appear in a renaming declaration, or part
3322 -- of an enclosing call given in prefix form.
3324 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3325 -- selected component should resolve to a name.
3327 if Ada_Version >= Ada_05
3328 and then Is_Tagged_Type (Prefix_Type)
3329 and then not Is_Concurrent_Type (Prefix_Type)
3331 if Nkind (Parent (N)) = N_Generic_Association
3332 or else Nkind (Parent (N)) = N_Requeue_Statement
3333 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3335 if Find_Primitive_Operation (N) then
3339 elsif Try_Object_Operation (N) then
3343 -- If the transformation fails, it will be necessary to redo the
3344 -- analysis with all errors enabled, to indicate candidate
3345 -- interpretations and reasons for each failure ???
3349 elsif Is_Private_Type (Prefix_Type) then
3351 -- Allow access only to discriminants of the type. If the type has
3352 -- no full view, gigi uses the parent type for the components, so we
3353 -- do the same here.
3355 if No (Full_View (Prefix_Type)) then
3356 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3357 Comp := First_Entity (Type_To_Use);
3360 while Present (Comp) loop
3361 if Chars (Comp) = Chars (Sel) then
3362 if Ekind (Comp) = E_Discriminant then
3363 Set_Entity_With_Style_Check (Sel, Comp);
3364 Generate_Reference (Comp, Sel);
3366 Set_Etype (Sel, Etype (Comp));
3367 Set_Etype (N, Etype (Comp));
3369 if Is_Generic_Type (Prefix_Type)
3370 or else Is_Generic_Type (Root_Type (Prefix_Type))
3372 Set_Original_Discriminant (Sel, Comp);
3375 -- Before declaring an error, check whether this is tagged
3376 -- private type and a call to a primitive operation.
3378 elsif Ada_Version >= Ada_05
3379 and then Is_Tagged_Type (Prefix_Type)
3380 and then Try_Object_Operation (N)
3386 ("invisible selector for }",
3387 N, First_Subtype (Prefix_Type));
3388 Set_Entity (Sel, Any_Id);
3389 Set_Etype (N, Any_Type);
3398 elsif Is_Concurrent_Type (Prefix_Type) then
3400 -- Find visible operation with given name. For a protected type,
3401 -- the possible candidates are discriminants, entries or protected
3402 -- procedures. For a task type, the set can only include entries or
3403 -- discriminants if the task type is not an enclosing scope. If it
3404 -- is an enclosing scope (e.g. in an inner task) then all entities
3405 -- are visible, but the prefix must denote the enclosing scope, i.e.
3406 -- can only be a direct name or an expanded name.
3408 Set_Etype (Sel, Any_Type);
3409 In_Scope := In_Open_Scopes (Prefix_Type);
3411 while Present (Comp) loop
3412 if Chars (Comp) = Chars (Sel) then
3413 if Is_Overloadable (Comp) then
3414 Add_One_Interp (Sel, Comp, Etype (Comp));
3416 -- If the prefix is tagged, the correct interpretation may
3417 -- lie in the primitive or class-wide operations of the
3418 -- type. Perform a simple conformance check to determine
3419 -- whether Try_Object_Operation should be invoked even if
3420 -- a visible entity is found.
3422 if Is_Tagged_Type (Prefix_Type)
3424 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3426 N_Indexed_Component)
3427 and then Has_Mode_Conformant_Spec (Comp)
3429 Has_Candidate := True;
3432 elsif Ekind (Comp) = E_Discriminant
3433 or else Ekind (Comp) = E_Entry_Family
3435 and then Is_Entity_Name (Name))
3437 Set_Entity_With_Style_Check (Sel, Comp);
3438 Generate_Reference (Comp, Sel);
3444 Set_Etype (Sel, Etype (Comp));
3445 Set_Etype (N, Etype (Comp));
3447 if Ekind (Comp) = E_Discriminant then
3448 Set_Original_Discriminant (Sel, Comp);
3451 -- For access type case, introduce explicit deference for more
3452 -- uniform treatment of entry calls.
3454 if Is_Access_Type (Etype (Name)) then
3455 Insert_Explicit_Dereference (Name);
3457 (Warn_On_Dereference, "?implicit dereference", N);
3463 exit when not In_Scope
3465 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3468 -- If there is no visible entity with the given name or none of the
3469 -- visible entities are plausible interpretations, check whether
3470 -- there is some other primitive operation with that name.
3472 if Ada_Version >= Ada_05
3473 and then Is_Tagged_Type (Prefix_Type)
3475 if (Etype (N) = Any_Type
3476 or else not Has_Candidate)
3477 and then Try_Object_Operation (N)
3481 -- If the context is not syntactically a procedure call, it
3482 -- may be a call to a primitive function declared outside of
3483 -- the synchronized type.
3485 -- If the context is a procedure call, there might still be
3486 -- an overloading between an entry and a primitive procedure
3487 -- declared outside of the synchronized type, called in prefix
3488 -- notation. This is harder to disambiguate because in one case
3489 -- the controlling formal is implicit ???
3491 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
3492 and then Nkind (Parent (N)) /= N_Indexed_Component
3493 and then Try_Object_Operation (N)
3499 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3504 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
3507 -- If N still has no type, the component is not defined in the prefix
3509 if Etype (N) = Any_Type then
3511 -- If the prefix is a single concurrent object, use its name in the
3512 -- error message, rather than that of its anonymous type.
3514 if Is_Concurrent_Type (Prefix_Type)
3515 and then Is_Internal_Name (Chars (Prefix_Type))
3516 and then not Is_Derived_Type (Prefix_Type)
3517 and then Is_Entity_Name (Name)
3520 Error_Msg_Node_2 := Entity (Name);
3521 Error_Msg_NE ("no selector& for&", N, Sel);
3523 Check_Misspelled_Selector (Type_To_Use, Sel);
3525 elsif Is_Generic_Type (Prefix_Type)
3526 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
3527 and then Prefix_Type /= Etype (Prefix_Type)
3528 and then Is_Record_Type (Etype (Prefix_Type))
3530 -- If this is a derived formal type, the parent may have
3531 -- different visibility at this point. Try for an inherited
3532 -- component before reporting an error.
3534 Set_Etype (Prefix (N), Etype (Prefix_Type));
3535 Analyze_Selected_Component (N);
3538 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
3539 and then Is_Generic_Actual_Type (Prefix_Type)
3540 and then Present (Full_View (Prefix_Type))
3542 -- Similarly, if this the actual for a formal derived type, the
3543 -- component inherited from the generic parent may not be visible
3544 -- in the actual, but the selected component is legal.
3551 First_Component (Generic_Parent_Type (Parent (Prefix_Type)));
3552 while Present (Comp) loop
3553 if Chars (Comp) = Chars (Sel) then
3554 Set_Entity_With_Style_Check (Sel, Comp);
3555 Set_Etype (Sel, Etype (Comp));
3556 Set_Etype (N, Etype (Comp));
3560 Next_Component (Comp);
3563 pragma Assert (Etype (N) /= Any_Type);
3567 if Ekind (Prefix_Type) = E_Record_Subtype then
3569 -- Check whether this is a component of the base type
3570 -- which is absent from a statically constrained subtype.
3571 -- This will raise constraint error at run-time, but is
3572 -- not a compile-time error. When the selector is illegal
3573 -- for base type as well fall through and generate a
3574 -- compilation error anyway.
3576 Comp := First_Component (Base_Type (Prefix_Type));
3577 while Present (Comp) loop
3578 if Chars (Comp) = Chars (Sel)
3579 and then Is_Visible_Component (Comp)
3581 Set_Entity_With_Style_Check (Sel, Comp);
3582 Generate_Reference (Comp, Sel);
3583 Set_Etype (Sel, Etype (Comp));
3584 Set_Etype (N, Etype (Comp));
3586 -- Emit appropriate message. Gigi will replace the
3587 -- node subsequently with the appropriate Raise.
3589 Apply_Compile_Time_Constraint_Error
3590 (N, "component not present in }?",
3591 CE_Discriminant_Check_Failed,
3592 Ent => Prefix_Type, Rep => False);
3593 Set_Raises_Constraint_Error (N);
3597 Next_Component (Comp);
3602 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3603 Error_Msg_NE ("no selector& for}", N, Sel);
3605 Check_Misspelled_Selector (Type_To_Use, Sel);
3608 Set_Entity (Sel, Any_Id);
3609 Set_Etype (Sel, Any_Type);
3611 end Analyze_Selected_Component;
3613 ---------------------------
3614 -- Analyze_Short_Circuit --
3615 ---------------------------
3617 procedure Analyze_Short_Circuit (N : Node_Id) is
3618 L : constant Node_Id := Left_Opnd (N);
3619 R : constant Node_Id := Right_Opnd (N);
3624 Analyze_Expression (L);
3625 Analyze_Expression (R);
3626 Set_Etype (N, Any_Type);
3628 if not Is_Overloaded (L) then
3629 if Root_Type (Etype (L)) = Standard_Boolean
3630 and then Has_Compatible_Type (R, Etype (L))
3632 Add_One_Interp (N, Etype (L), Etype (L));
3636 Get_First_Interp (L, Ind, It);
3637 while Present (It.Typ) loop
3638 if Root_Type (It.Typ) = Standard_Boolean
3639 and then Has_Compatible_Type (R, It.Typ)
3641 Add_One_Interp (N, It.Typ, It.Typ);
3644 Get_Next_Interp (Ind, It);
3648 -- Here we have failed to find an interpretation. Clearly we know that
3649 -- it is not the case that both operands can have an interpretation of
3650 -- Boolean, but this is by far the most likely intended interpretation.
3651 -- So we simply resolve both operands as Booleans, and at least one of
3652 -- these resolutions will generate an error message, and we do not need
3653 -- to give another error message on the short circuit operation itself.
3655 if Etype (N) = Any_Type then
3656 Resolve (L, Standard_Boolean);
3657 Resolve (R, Standard_Boolean);
3658 Set_Etype (N, Standard_Boolean);
3660 end Analyze_Short_Circuit;
3666 procedure Analyze_Slice (N : Node_Id) is
3667 P : constant Node_Id := Prefix (N);
3668 D : constant Node_Id := Discrete_Range (N);
3669 Array_Type : Entity_Id;
3671 procedure Analyze_Overloaded_Slice;
3672 -- If the prefix is overloaded, select those interpretations that
3673 -- yield a one-dimensional array type.
3675 ------------------------------
3676 -- Analyze_Overloaded_Slice --
3677 ------------------------------
3679 procedure Analyze_Overloaded_Slice is
3685 Set_Etype (N, Any_Type);
3687 Get_First_Interp (P, I, It);
3688 while Present (It.Nam) loop
3691 if Is_Access_Type (Typ) then
3692 Typ := Designated_Type (Typ);
3693 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3696 if Is_Array_Type (Typ)
3697 and then Number_Dimensions (Typ) = 1
3698 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
3700 Add_One_Interp (N, Typ, Typ);
3703 Get_Next_Interp (I, It);
3706 if Etype (N) = Any_Type then
3707 Error_Msg_N ("expect array type in prefix of slice", N);
3709 end Analyze_Overloaded_Slice;
3711 -- Start of processing for Analyze_Slice
3717 if Is_Overloaded (P) then
3718 Analyze_Overloaded_Slice;
3721 Array_Type := Etype (P);
3722 Set_Etype (N, Any_Type);
3724 if Is_Access_Type (Array_Type) then
3725 Array_Type := Designated_Type (Array_Type);
3726 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3729 if not Is_Array_Type (Array_Type) then
3730 Wrong_Type (P, Any_Array);
3732 elsif Number_Dimensions (Array_Type) > 1 then
3734 ("type is not one-dimensional array in slice prefix", N);
3737 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
3739 Wrong_Type (D, Etype (First_Index (Array_Type)));
3742 Set_Etype (N, Array_Type);
3747 -----------------------------
3748 -- Analyze_Type_Conversion --
3749 -----------------------------
3751 procedure Analyze_Type_Conversion (N : Node_Id) is
3752 Expr : constant Node_Id := Expression (N);
3756 -- If Conversion_OK is set, then the Etype is already set, and the
3757 -- only processing required is to analyze the expression. This is
3758 -- used to construct certain "illegal" conversions which are not
3759 -- allowed by Ada semantics, but can be handled OK by Gigi, see
3760 -- Sinfo for further details.
3762 if Conversion_OK (N) then
3767 -- Otherwise full type analysis is required, as well as some semantic
3768 -- checks to make sure the argument of the conversion is appropriate.
3770 Find_Type (Subtype_Mark (N));
3771 T := Entity (Subtype_Mark (N));
3773 Check_Fully_Declared (T, N);
3774 Analyze_Expression (Expr);
3775 Validate_Remote_Type_Type_Conversion (N);
3777 -- Only remaining step is validity checks on the argument. These
3778 -- are skipped if the conversion does not come from the source.
3780 if not Comes_From_Source (N) then
3783 -- If there was an error in a generic unit, no need to replicate the
3784 -- error message. Conversely, constant-folding in the generic may
3785 -- transform the argument of a conversion into a string literal, which
3786 -- is legal. Therefore the following tests are not performed in an
3789 elsif In_Instance then
3792 elsif Nkind (Expr) = N_Null then
3793 Error_Msg_N ("argument of conversion cannot be null", N);
3794 Error_Msg_N ("\use qualified expression instead", N);
3795 Set_Etype (N, Any_Type);
3797 elsif Nkind (Expr) = N_Aggregate then
3798 Error_Msg_N ("argument of conversion cannot be aggregate", N);
3799 Error_Msg_N ("\use qualified expression instead", N);
3801 elsif Nkind (Expr) = N_Allocator then
3802 Error_Msg_N ("argument of conversion cannot be an allocator", N);
3803 Error_Msg_N ("\use qualified expression instead", N);
3805 elsif Nkind (Expr) = N_String_Literal then
3806 Error_Msg_N ("argument of conversion cannot be string literal", N);
3807 Error_Msg_N ("\use qualified expression instead", N);
3809 elsif Nkind (Expr) = N_Character_Literal then
3810 if Ada_Version = Ada_83 then
3813 Error_Msg_N ("argument of conversion cannot be character literal",
3815 Error_Msg_N ("\use qualified expression instead", N);
3818 elsif Nkind (Expr) = N_Attribute_Reference
3820 (Attribute_Name (Expr) = Name_Access or else
3821 Attribute_Name (Expr) = Name_Unchecked_Access or else
3822 Attribute_Name (Expr) = Name_Unrestricted_Access)
3824 Error_Msg_N ("argument of conversion cannot be access", N);
3825 Error_Msg_N ("\use qualified expression instead", N);
3827 end Analyze_Type_Conversion;
3829 ----------------------
3830 -- Analyze_Unary_Op --
3831 ----------------------
3833 procedure Analyze_Unary_Op (N : Node_Id) is
3834 R : constant Node_Id := Right_Opnd (N);
3835 Op_Id : Entity_Id := Entity (N);
3838 Set_Etype (N, Any_Type);
3839 Candidate_Type := Empty;
3841 Analyze_Expression (R);
3843 if Present (Op_Id) then
3844 if Ekind (Op_Id) = E_Operator then
3845 Find_Unary_Types (R, Op_Id, N);
3847 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3851 Op_Id := Get_Name_Entity_Id (Chars (N));
3852 while Present (Op_Id) loop
3853 if Ekind (Op_Id) = E_Operator then
3854 if No (Next_Entity (First_Entity (Op_Id))) then
3855 Find_Unary_Types (R, Op_Id, N);
3858 elsif Is_Overloadable (Op_Id) then
3859 Analyze_User_Defined_Unary_Op (N, Op_Id);
3862 Op_Id := Homonym (Op_Id);
3867 end Analyze_Unary_Op;
3869 ----------------------------------
3870 -- Analyze_Unchecked_Expression --
3871 ----------------------------------
3873 procedure Analyze_Unchecked_Expression (N : Node_Id) is
3875 Analyze (Expression (N), Suppress => All_Checks);
3876 Set_Etype (N, Etype (Expression (N)));
3877 Save_Interps (Expression (N), N);
3878 end Analyze_Unchecked_Expression;
3880 ---------------------------------------
3881 -- Analyze_Unchecked_Type_Conversion --
3882 ---------------------------------------
3884 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
3886 Find_Type (Subtype_Mark (N));
3887 Analyze_Expression (Expression (N));
3888 Set_Etype (N, Entity (Subtype_Mark (N)));
3889 end Analyze_Unchecked_Type_Conversion;
3891 ------------------------------------
3892 -- Analyze_User_Defined_Binary_Op --
3893 ------------------------------------
3895 procedure Analyze_User_Defined_Binary_Op
3900 -- Only do analysis if the operator Comes_From_Source, since otherwise
3901 -- the operator was generated by the expander, and all such operators
3902 -- always refer to the operators in package Standard.
3904 if Comes_From_Source (N) then
3906 F1 : constant Entity_Id := First_Formal (Op_Id);
3907 F2 : constant Entity_Id := Next_Formal (F1);
3910 -- Verify that Op_Id is a visible binary function. Note that since
3911 -- we know Op_Id is overloaded, potentially use visible means use
3912 -- visible for sure (RM 9.4(11)).
3914 if Ekind (Op_Id) = E_Function
3915 and then Present (F2)
3916 and then (Is_Immediately_Visible (Op_Id)
3917 or else Is_Potentially_Use_Visible (Op_Id))
3918 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
3919 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
3921 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3923 -- If the left operand is overloaded, indicate that the
3924 -- current type is a viable candidate. This is redundant
3925 -- in most cases, but for equality and comparison operators
3926 -- where the context does not impose a type on the operands,
3927 -- setting the proper type is necessary to avoid subsequent
3928 -- ambiguities during resolution, when both user-defined and
3929 -- predefined operators may be candidates.
3931 if Is_Overloaded (Left_Opnd (N)) then
3932 Set_Etype (Left_Opnd (N), Etype (F1));
3935 if Debug_Flag_E then
3936 Write_Str ("user defined operator ");
3937 Write_Name (Chars (Op_Id));
3938 Write_Str (" on node ");
3939 Write_Int (Int (N));
3945 end Analyze_User_Defined_Binary_Op;
3947 -----------------------------------
3948 -- Analyze_User_Defined_Unary_Op --
3949 -----------------------------------
3951 procedure Analyze_User_Defined_Unary_Op
3956 -- Only do analysis if the operator Comes_From_Source, since otherwise
3957 -- the operator was generated by the expander, and all such operators
3958 -- always refer to the operators in package Standard.
3960 if Comes_From_Source (N) then
3962 F : constant Entity_Id := First_Formal (Op_Id);
3965 -- Verify that Op_Id is a visible unary function. Note that since
3966 -- we know Op_Id is overloaded, potentially use visible means use
3967 -- visible for sure (RM 9.4(11)).
3969 if Ekind (Op_Id) = E_Function
3970 and then No (Next_Formal (F))
3971 and then (Is_Immediately_Visible (Op_Id)
3972 or else Is_Potentially_Use_Visible (Op_Id))
3973 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
3975 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3979 end Analyze_User_Defined_Unary_Op;
3981 ---------------------------
3982 -- Check_Arithmetic_Pair --
3983 ---------------------------
3985 procedure Check_Arithmetic_Pair
3986 (T1, T2 : Entity_Id;
3990 Op_Name : constant Name_Id := Chars (Op_Id);
3992 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
3993 -- Check whether the fixed-point type Typ has a user-defined operator
3994 -- (multiplication or division) that should hide the corresponding
3995 -- predefined operator. Used to implement Ada 2005 AI-264, to make
3996 -- such operators more visible and therefore useful.
3998 -- If the name of the operation is an expanded name with prefix
3999 -- Standard, the predefined universal fixed operator is available,
4000 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
4002 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
4003 -- Get specific type (i.e. non-universal type if there is one)
4009 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
4010 Bas : constant Entity_Id := Base_Type (Typ);
4016 -- If the universal_fixed operation is given explicitly the rule
4017 -- concerning primitive operations of the type do not apply.
4019 if Nkind (N) = N_Function_Call
4020 and then Nkind (Name (N)) = N_Expanded_Name
4021 and then Entity (Prefix (Name (N))) = Standard_Standard
4026 -- The operation is treated as primitive if it is declared in the
4027 -- same scope as the type, and therefore on the same entity chain.
4029 Ent := Next_Entity (Typ);
4030 while Present (Ent) loop
4031 if Chars (Ent) = Chars (Op) then
4032 F1 := First_Formal (Ent);
4033 F2 := Next_Formal (F1);
4035 -- The operation counts as primitive if either operand or
4036 -- result are of the given base type, and both operands are
4037 -- fixed point types.
4039 if (Base_Type (Etype (F1)) = Bas
4040 and then Is_Fixed_Point_Type (Etype (F2)))
4043 (Base_Type (Etype (F2)) = Bas
4044 and then Is_Fixed_Point_Type (Etype (F1)))
4047 (Base_Type (Etype (Ent)) = Bas
4048 and then Is_Fixed_Point_Type (Etype (F1))
4049 and then Is_Fixed_Point_Type (Etype (F2)))
4065 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4067 if T1 = Universal_Integer or else T1 = Universal_Real then
4068 return Base_Type (T2);
4070 return Base_Type (T1);
4074 -- Start of processing for Check_Arithmetic_Pair
4077 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4079 if Is_Numeric_Type (T1)
4080 and then Is_Numeric_Type (T2)
4081 and then (Covers (T1 => T1, T2 => T2)
4083 Covers (T1 => T2, T2 => T1))
4085 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4088 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4090 if Is_Fixed_Point_Type (T1)
4091 and then (Is_Fixed_Point_Type (T2)
4092 or else T2 = Universal_Real)
4094 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4095 -- and no further processing is required (this is the case of an
4096 -- operator constructed by Exp_Fixd for a fixed point operation)
4097 -- Otherwise add one interpretation with universal fixed result
4098 -- If the operator is given in functional notation, it comes
4099 -- from source and Fixed_As_Integer cannot apply.
4101 if (Nkind (N) not in N_Op
4102 or else not Treat_Fixed_As_Integer (N))
4104 (not Has_Fixed_Op (T1, Op_Id)
4105 or else Nkind (Parent (N)) = N_Type_Conversion)
4107 Add_One_Interp (N, Op_Id, Universal_Fixed);
4110 elsif Is_Fixed_Point_Type (T2)
4111 and then (Nkind (N) not in N_Op
4112 or else not Treat_Fixed_As_Integer (N))
4113 and then T1 = Universal_Real
4115 (not Has_Fixed_Op (T1, Op_Id)
4116 or else Nkind (Parent (N)) = N_Type_Conversion)
4118 Add_One_Interp (N, Op_Id, Universal_Fixed);
4120 elsif Is_Numeric_Type (T1)
4121 and then Is_Numeric_Type (T2)
4122 and then (Covers (T1 => T1, T2 => T2)
4124 Covers (T1 => T2, T2 => T1))
4126 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4128 elsif Is_Fixed_Point_Type (T1)
4129 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4130 or else T2 = Universal_Integer)
4132 Add_One_Interp (N, Op_Id, T1);
4134 elsif T2 = Universal_Real
4135 and then Base_Type (T1) = Base_Type (Standard_Integer)
4136 and then Op_Name = Name_Op_Multiply
4138 Add_One_Interp (N, Op_Id, Any_Fixed);
4140 elsif T1 = Universal_Real
4141 and then Base_Type (T2) = Base_Type (Standard_Integer)
4143 Add_One_Interp (N, Op_Id, Any_Fixed);
4145 elsif Is_Fixed_Point_Type (T2)
4146 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4147 or else T1 = Universal_Integer)
4148 and then Op_Name = Name_Op_Multiply
4150 Add_One_Interp (N, Op_Id, T2);
4152 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4153 Add_One_Interp (N, Op_Id, T1);
4155 elsif T2 = Universal_Real
4156 and then T1 = Universal_Integer
4157 and then Op_Name = Name_Op_Multiply
4159 Add_One_Interp (N, Op_Id, T2);
4162 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4164 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4165 -- set does not require any special processing, since the Etype is
4166 -- already set (case of operation constructed by Exp_Fixed).
4168 if Is_Integer_Type (T1)
4169 and then (Covers (T1 => T1, T2 => T2)
4171 Covers (T1 => T2, T2 => T1))
4173 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4176 elsif Op_Name = Name_Op_Expon then
4177 if Is_Numeric_Type (T1)
4178 and then not Is_Fixed_Point_Type (T1)
4179 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4180 or else T2 = Universal_Integer)
4182 Add_One_Interp (N, Op_Id, Base_Type (T1));
4185 else pragma Assert (Nkind (N) in N_Op_Shift);
4187 -- If not one of the predefined operators, the node may be one
4188 -- of the intrinsic functions. Its kind is always specific, and
4189 -- we can use it directly, rather than the name of the operation.
4191 if Is_Integer_Type (T1)
4192 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4193 or else T2 = Universal_Integer)
4195 Add_One_Interp (N, Op_Id, Base_Type (T1));
4198 end Check_Arithmetic_Pair;
4200 -------------------------------
4201 -- Check_Misspelled_Selector --
4202 -------------------------------
4204 procedure Check_Misspelled_Selector
4205 (Prefix : Entity_Id;
4208 Max_Suggestions : constant := 2;
4209 Nr_Of_Suggestions : Natural := 0;
4211 Suggestion_1 : Entity_Id := Empty;
4212 Suggestion_2 : Entity_Id := Empty;
4217 -- All the components of the prefix of selector Sel are matched
4218 -- against Sel and a count is maintained of possible misspellings.
4219 -- When at the end of the analysis there are one or two (not more!)
4220 -- possible misspellings, these misspellings will be suggested as
4221 -- possible correction.
4223 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4225 -- Concurrent types should be handled as well ???
4230 Comp := First_Entity (Prefix);
4231 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4232 if Is_Visible_Component (Comp) then
4233 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4234 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4236 case Nr_Of_Suggestions is
4237 when 1 => Suggestion_1 := Comp;
4238 when 2 => Suggestion_2 := Comp;
4239 when others => exit;
4244 Comp := Next_Entity (Comp);
4247 -- Report at most two suggestions
4249 if Nr_Of_Suggestions = 1 then
4250 Error_Msg_NE -- CODEFIX
4251 ("\possible misspelling of&", Sel, Suggestion_1);
4253 elsif Nr_Of_Suggestions = 2 then
4254 Error_Msg_Node_2 := Suggestion_2;
4255 Error_Msg_NE -- CODEFIX
4256 ("\possible misspelling of& or&", Sel, Suggestion_1);
4258 end Check_Misspelled_Selector;
4260 ----------------------
4261 -- Defined_In_Scope --
4262 ----------------------
4264 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4266 S1 : constant Entity_Id := Scope (Base_Type (T));
4269 or else (S1 = System_Aux_Id and then S = Scope (S1));
4270 end Defined_In_Scope;
4276 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4282 Void_Interp_Seen : Boolean := False;
4285 pragma Warnings (Off, Boolean);
4288 if Ada_Version >= Ada_05 then
4289 Actual := First_Actual (N);
4290 while Present (Actual) loop
4292 -- Ada 2005 (AI-50217): Post an error in case of premature
4293 -- usage of an entity from the limited view.
4295 if not Analyzed (Etype (Actual))
4296 and then From_With_Type (Etype (Actual))
4298 Error_Msg_Qual_Level := 1;
4300 ("missing with_clause for scope of imported type&",
4301 Actual, Etype (Actual));
4302 Error_Msg_Qual_Level := 0;
4305 Next_Actual (Actual);
4309 -- Analyze each candidate call again, with full error reporting
4313 ("no candidate interpretations match the actuals:!", Nam);
4314 Err_Mode := All_Errors_Mode;
4315 All_Errors_Mode := True;
4317 -- If this is a call to an operation of a concurrent type,
4318 -- the failed interpretations have been removed from the
4319 -- name. Recover them to provide full diagnostics.
4321 if Nkind (Parent (Nam)) = N_Selected_Component then
4322 Set_Entity (Nam, Empty);
4323 New_Nam := New_Copy_Tree (Parent (Nam));
4324 Set_Is_Overloaded (New_Nam, False);
4325 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4326 Set_Parent (New_Nam, Parent (Parent (Nam)));
4327 Analyze_Selected_Component (New_Nam);
4328 Get_First_Interp (Selector_Name (New_Nam), X, It);
4330 Get_First_Interp (Nam, X, It);
4333 while Present (It.Nam) loop
4334 if Etype (It.Nam) = Standard_Void_Type then
4335 Void_Interp_Seen := True;
4338 Analyze_One_Call (N, It.Nam, True, Success);
4339 Get_Next_Interp (X, It);
4342 if Nkind (N) = N_Function_Call then
4343 Get_First_Interp (Nam, X, It);
4344 while Present (It.Nam) loop
4345 if Ekind (It.Nam) = E_Function
4346 or else Ekind (It.Nam) = E_Operator
4350 Get_Next_Interp (X, It);
4354 -- If all interpretations are procedures, this deserves a
4355 -- more precise message. Ditto if this appears as the prefix
4356 -- of a selected component, which may be a lexical error.
4359 ("\context requires function call, found procedure name", Nam);
4361 if Nkind (Parent (N)) = N_Selected_Component
4362 and then N = Prefix (Parent (N))
4364 Error_Msg_N -- CODEFIX
4365 ("\period should probably be semicolon", Parent (N));
4368 elsif Nkind (N) = N_Procedure_Call_Statement
4369 and then not Void_Interp_Seen
4372 "\function name found in procedure call", Nam);
4375 All_Errors_Mode := Err_Mode;
4378 ---------------------------
4379 -- Find_Arithmetic_Types --
4380 ---------------------------
4382 procedure Find_Arithmetic_Types
4387 Index1 : Interp_Index;
4388 Index2 : Interp_Index;
4392 procedure Check_Right_Argument (T : Entity_Id);
4393 -- Check right operand of operator
4395 --------------------------
4396 -- Check_Right_Argument --
4397 --------------------------
4399 procedure Check_Right_Argument (T : Entity_Id) is
4401 if not Is_Overloaded (R) then
4402 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4404 Get_First_Interp (R, Index2, It2);
4405 while Present (It2.Typ) loop
4406 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4407 Get_Next_Interp (Index2, It2);
4410 end Check_Right_Argument;
4412 -- Start of processing for Find_Arithmetic_Types
4415 if not Is_Overloaded (L) then
4416 Check_Right_Argument (Etype (L));
4419 Get_First_Interp (L, Index1, It1);
4420 while Present (It1.Typ) loop
4421 Check_Right_Argument (It1.Typ);
4422 Get_Next_Interp (Index1, It1);
4426 end Find_Arithmetic_Types;
4428 ------------------------
4429 -- Find_Boolean_Types --
4430 ------------------------
4432 procedure Find_Boolean_Types
4437 Index : Interp_Index;
4440 procedure Check_Numeric_Argument (T : Entity_Id);
4441 -- Special case for logical operations one of whose operands is an
4442 -- integer literal. If both are literal the result is any modular type.
4444 ----------------------------
4445 -- Check_Numeric_Argument --
4446 ----------------------------
4448 procedure Check_Numeric_Argument (T : Entity_Id) is
4450 if T = Universal_Integer then
4451 Add_One_Interp (N, Op_Id, Any_Modular);
4453 elsif Is_Modular_Integer_Type (T) then
4454 Add_One_Interp (N, Op_Id, T);
4456 end Check_Numeric_Argument;
4458 -- Start of processing for Find_Boolean_Types
4461 if not Is_Overloaded (L) then
4462 if Etype (L) = Universal_Integer
4463 or else Etype (L) = Any_Modular
4465 if not Is_Overloaded (R) then
4466 Check_Numeric_Argument (Etype (R));
4469 Get_First_Interp (R, Index, It);
4470 while Present (It.Typ) loop
4471 Check_Numeric_Argument (It.Typ);
4472 Get_Next_Interp (Index, It);
4476 -- If operands are aggregates, we must assume that they may be
4477 -- boolean arrays, and leave disambiguation for the second pass.
4478 -- If only one is an aggregate, verify that the other one has an
4479 -- interpretation as a boolean array
4481 elsif Nkind (L) = N_Aggregate then
4482 if Nkind (R) = N_Aggregate then
4483 Add_One_Interp (N, Op_Id, Etype (L));
4485 elsif not Is_Overloaded (R) then
4486 if Valid_Boolean_Arg (Etype (R)) then
4487 Add_One_Interp (N, Op_Id, Etype (R));
4491 Get_First_Interp (R, Index, It);
4492 while Present (It.Typ) loop
4493 if Valid_Boolean_Arg (It.Typ) then
4494 Add_One_Interp (N, Op_Id, It.Typ);
4497 Get_Next_Interp (Index, It);
4501 elsif Valid_Boolean_Arg (Etype (L))
4502 and then Has_Compatible_Type (R, Etype (L))
4504 Add_One_Interp (N, Op_Id, Etype (L));
4508 Get_First_Interp (L, Index, It);
4509 while Present (It.Typ) loop
4510 if Valid_Boolean_Arg (It.Typ)
4511 and then Has_Compatible_Type (R, It.Typ)
4513 Add_One_Interp (N, Op_Id, It.Typ);
4516 Get_Next_Interp (Index, It);
4519 end Find_Boolean_Types;
4521 ---------------------------
4522 -- Find_Comparison_Types --
4523 ---------------------------
4525 procedure Find_Comparison_Types
4530 Index : Interp_Index;
4532 Found : Boolean := False;
4535 Scop : Entity_Id := Empty;
4537 procedure Try_One_Interp (T1 : Entity_Id);
4538 -- Routine to try one proposed interpretation. Note that the context
4539 -- of the operator plays no role in resolving the arguments, so that
4540 -- if there is more than one interpretation of the operands that is
4541 -- compatible with comparison, the operation is ambiguous.
4543 --------------------
4544 -- Try_One_Interp --
4545 --------------------
4547 procedure Try_One_Interp (T1 : Entity_Id) is
4550 -- If the operator is an expanded name, then the type of the operand
4551 -- must be defined in the corresponding scope. If the type is
4552 -- universal, the context will impose the correct type.
4555 and then not Defined_In_Scope (T1, Scop)
4556 and then T1 /= Universal_Integer
4557 and then T1 /= Universal_Real
4558 and then T1 /= Any_String
4559 and then T1 /= Any_Composite
4564 if Valid_Comparison_Arg (T1)
4565 and then Has_Compatible_Type (R, T1)
4568 and then Base_Type (T1) /= Base_Type (T_F)
4570 It := Disambiguate (L, I_F, Index, Any_Type);
4572 if It = No_Interp then
4573 Ambiguous_Operands (N);
4574 Set_Etype (L, Any_Type);
4588 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4593 -- Start of processing for Find_Comparison_Types
4596 -- If left operand is aggregate, the right operand has to
4597 -- provide a usable type for it.
4599 if Nkind (L) = N_Aggregate
4600 and then Nkind (R) /= N_Aggregate
4602 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4606 if Nkind (N) = N_Function_Call
4607 and then Nkind (Name (N)) = N_Expanded_Name
4609 Scop := Entity (Prefix (Name (N)));
4611 -- The prefix may be a package renaming, and the subsequent test
4612 -- requires the original package.
4614 if Ekind (Scop) = E_Package
4615 and then Present (Renamed_Entity (Scop))
4617 Scop := Renamed_Entity (Scop);
4618 Set_Entity (Prefix (Name (N)), Scop);
4622 if not Is_Overloaded (L) then
4623 Try_One_Interp (Etype (L));
4626 Get_First_Interp (L, Index, It);
4627 while Present (It.Typ) loop
4628 Try_One_Interp (It.Typ);
4629 Get_Next_Interp (Index, It);
4632 end Find_Comparison_Types;
4634 ----------------------------------------
4635 -- Find_Non_Universal_Interpretations --
4636 ----------------------------------------
4638 procedure Find_Non_Universal_Interpretations
4644 Index : Interp_Index;
4648 if T1 = Universal_Integer
4649 or else T1 = Universal_Real
4651 if not Is_Overloaded (R) then
4653 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
4655 Get_First_Interp (R, Index, It);
4656 while Present (It.Typ) loop
4657 if Covers (It.Typ, T1) then
4659 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
4662 Get_Next_Interp (Index, It);
4666 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
4668 end Find_Non_Universal_Interpretations;
4670 ------------------------------
4671 -- Find_Concatenation_Types --
4672 ------------------------------
4674 procedure Find_Concatenation_Types
4679 Op_Type : constant Entity_Id := Etype (Op_Id);
4682 if Is_Array_Type (Op_Type)
4683 and then not Is_Limited_Type (Op_Type)
4685 and then (Has_Compatible_Type (L, Op_Type)
4687 Has_Compatible_Type (L, Component_Type (Op_Type)))
4689 and then (Has_Compatible_Type (R, Op_Type)
4691 Has_Compatible_Type (R, Component_Type (Op_Type)))
4693 Add_One_Interp (N, Op_Id, Op_Type);
4695 end Find_Concatenation_Types;
4697 -------------------------
4698 -- Find_Equality_Types --
4699 -------------------------
4701 procedure Find_Equality_Types
4706 Index : Interp_Index;
4708 Found : Boolean := False;
4711 Scop : Entity_Id := Empty;
4713 procedure Try_One_Interp (T1 : Entity_Id);
4714 -- The context of the equality operator plays no role in resolving the
4715 -- arguments, so that if there is more than one interpretation of the
4716 -- operands that is compatible with equality, the construct is ambiguous
4717 -- and an error can be emitted now, after trying to disambiguate, i.e.
4718 -- applying preference rules.
4720 --------------------
4721 -- Try_One_Interp --
4722 --------------------
4724 procedure Try_One_Interp (T1 : Entity_Id) is
4725 Bas : constant Entity_Id := Base_Type (T1);
4728 -- If the operator is an expanded name, then the type of the operand
4729 -- must be defined in the corresponding scope. If the type is
4730 -- universal, the context will impose the correct type. An anonymous
4731 -- type for a 'Access reference is also universal in this sense, as
4732 -- the actual type is obtained from context.
4733 -- In Ada 2005, the equality operator for anonymous access types
4734 -- is declared in Standard, and preference rules apply to it.
4736 if Present (Scop) then
4737 if Defined_In_Scope (T1, Scop)
4738 or else T1 = Universal_Integer
4739 or else T1 = Universal_Real
4740 or else T1 = Any_Access
4741 or else T1 = Any_String
4742 or else T1 = Any_Composite
4743 or else (Ekind (T1) = E_Access_Subprogram_Type
4744 and then not Comes_From_Source (T1))
4748 elsif Ekind (T1) = E_Anonymous_Access_Type
4749 and then Scop = Standard_Standard
4754 -- The scope does not contain an operator for the type
4759 -- If we have infix notation, the operator must be usable.
4760 -- Within an instance, if the type is already established we
4761 -- know it is correct.
4762 -- In Ada 2005, the equality on anonymous access types is declared
4763 -- in Standard, and is always visible.
4765 elsif In_Open_Scopes (Scope (Bas))
4766 or else Is_Potentially_Use_Visible (Bas)
4767 or else In_Use (Bas)
4768 or else (In_Use (Scope (Bas))
4769 and then not Is_Hidden (Bas))
4770 or else (In_Instance
4771 and then First_Subtype (T1) = First_Subtype (Etype (R)))
4772 or else Ekind (T1) = E_Anonymous_Access_Type
4777 -- Save candidate type for subsquent error message, if any
4779 if not Is_Limited_Type (T1) then
4780 Candidate_Type := T1;
4786 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
4787 -- Do not allow anonymous access types in equality operators.
4789 if Ada_Version < Ada_05
4790 and then Ekind (T1) = E_Anonymous_Access_Type
4795 if T1 /= Standard_Void_Type
4796 and then not Is_Limited_Type (T1)
4797 and then not Is_Limited_Composite (T1)
4798 and then Has_Compatible_Type (R, T1)
4801 and then Base_Type (T1) /= Base_Type (T_F)
4803 It := Disambiguate (L, I_F, Index, Any_Type);
4805 if It = No_Interp then
4806 Ambiguous_Operands (N);
4807 Set_Etype (L, Any_Type);
4820 if not Analyzed (L) then
4824 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4826 -- Case of operator was not visible, Etype still set to Any_Type
4828 if Etype (N) = Any_Type then
4832 elsif Scop = Standard_Standard
4833 and then Ekind (T1) = E_Anonymous_Access_Type
4839 -- Start of processing for Find_Equality_Types
4842 -- If left operand is aggregate, the right operand has to
4843 -- provide a usable type for it.
4845 if Nkind (L) = N_Aggregate
4846 and then Nkind (R) /= N_Aggregate
4848 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4852 if Nkind (N) = N_Function_Call
4853 and then Nkind (Name (N)) = N_Expanded_Name
4855 Scop := Entity (Prefix (Name (N)));
4857 -- The prefix may be a package renaming, and the subsequent test
4858 -- requires the original package.
4860 if Ekind (Scop) = E_Package
4861 and then Present (Renamed_Entity (Scop))
4863 Scop := Renamed_Entity (Scop);
4864 Set_Entity (Prefix (Name (N)), Scop);
4868 if not Is_Overloaded (L) then
4869 Try_One_Interp (Etype (L));
4872 Get_First_Interp (L, Index, It);
4873 while Present (It.Typ) loop
4874 Try_One_Interp (It.Typ);
4875 Get_Next_Interp (Index, It);
4878 end Find_Equality_Types;
4880 -------------------------
4881 -- Find_Negation_Types --
4882 -------------------------
4884 procedure Find_Negation_Types
4889 Index : Interp_Index;
4893 if not Is_Overloaded (R) then
4894 if Etype (R) = Universal_Integer then
4895 Add_One_Interp (N, Op_Id, Any_Modular);
4896 elsif Valid_Boolean_Arg (Etype (R)) then
4897 Add_One_Interp (N, Op_Id, Etype (R));
4901 Get_First_Interp (R, Index, It);
4902 while Present (It.Typ) loop
4903 if Valid_Boolean_Arg (It.Typ) then
4904 Add_One_Interp (N, Op_Id, It.Typ);
4907 Get_Next_Interp (Index, It);
4910 end Find_Negation_Types;
4912 ------------------------------
4913 -- Find_Primitive_Operation --
4914 ------------------------------
4916 function Find_Primitive_Operation (N : Node_Id) return Boolean is
4917 Obj : constant Node_Id := Prefix (N);
4918 Op : constant Node_Id := Selector_Name (N);
4925 Set_Etype (Op, Any_Type);
4927 if Is_Access_Type (Etype (Obj)) then
4928 Typ := Designated_Type (Etype (Obj));
4933 if Is_Class_Wide_Type (Typ) then
4934 Typ := Root_Type (Typ);
4937 Prims := Primitive_Operations (Typ);
4939 Prim := First_Elmt (Prims);
4940 while Present (Prim) loop
4941 if Chars (Node (Prim)) = Chars (Op) then
4942 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
4943 Set_Etype (N, Etype (Node (Prim)));
4949 -- Now look for class-wide operations of the type or any of its
4950 -- ancestors by iterating over the homonyms of the selector.
4953 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
4957 Hom := Current_Entity (Op);
4958 while Present (Hom) loop
4959 if (Ekind (Hom) = E_Procedure
4961 Ekind (Hom) = E_Function)
4962 and then Scope (Hom) = Scope (Typ)
4963 and then Present (First_Formal (Hom))
4965 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
4967 (Is_Access_Type (Etype (First_Formal (Hom)))
4969 Ekind (Etype (First_Formal (Hom))) =
4970 E_Anonymous_Access_Type
4973 (Designated_Type (Etype (First_Formal (Hom)))) =
4976 Add_One_Interp (Op, Hom, Etype (Hom));
4977 Set_Etype (N, Etype (Hom));
4980 Hom := Homonym (Hom);
4984 return Etype (Op) /= Any_Type;
4985 end Find_Primitive_Operation;
4987 ----------------------
4988 -- Find_Unary_Types --
4989 ----------------------
4991 procedure Find_Unary_Types
4996 Index : Interp_Index;
5000 if not Is_Overloaded (R) then
5001 if Is_Numeric_Type (Etype (R)) then
5002 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
5006 Get_First_Interp (R, Index, It);
5007 while Present (It.Typ) loop
5008 if Is_Numeric_Type (It.Typ) then
5009 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
5012 Get_Next_Interp (Index, It);
5015 end Find_Unary_Types;
5021 function Junk_Operand (N : Node_Id) return Boolean is
5025 if Error_Posted (N) then
5029 -- Get entity to be tested
5031 if Is_Entity_Name (N)
5032 and then Present (Entity (N))
5036 -- An odd case, a procedure name gets converted to a very peculiar
5037 -- function call, and here is where we detect this happening.
5039 elsif Nkind (N) = N_Function_Call
5040 and then Is_Entity_Name (Name (N))
5041 and then Present (Entity (Name (N)))
5045 -- Another odd case, there are at least some cases of selected
5046 -- components where the selected component is not marked as having
5047 -- an entity, even though the selector does have an entity
5049 elsif Nkind (N) = N_Selected_Component
5050 and then Present (Entity (Selector_Name (N)))
5052 Enode := Selector_Name (N);
5058 -- Now test the entity we got to see if it is a bad case
5060 case Ekind (Entity (Enode)) is
5064 ("package name cannot be used as operand", Enode);
5066 when Generic_Unit_Kind =>
5068 ("generic unit name cannot be used as operand", Enode);
5072 ("subtype name cannot be used as operand", Enode);
5076 ("entry name cannot be used as operand", Enode);
5080 ("procedure name cannot be used as operand", Enode);
5084 ("exception name cannot be used as operand", Enode);
5086 when E_Block | E_Label | E_Loop =>
5088 ("label name cannot be used as operand", Enode);
5098 --------------------
5099 -- Operator_Check --
5100 --------------------
5102 procedure Operator_Check (N : Node_Id) is
5104 Remove_Abstract_Operations (N);
5106 -- Test for case of no interpretation found for operator
5108 if Etype (N) = Any_Type then
5112 Op_Id : Entity_Id := Empty;
5115 R := Right_Opnd (N);
5117 if Nkind (N) in N_Binary_Op then
5123 -- If either operand has no type, then don't complain further,
5124 -- since this simply means that we have a propagated error.
5127 or else Etype (R) = Any_Type
5128 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5132 -- We explicitly check for the case of concatenation of component
5133 -- with component to avoid reporting spurious matching array types
5134 -- that might happen to be lurking in distant packages (such as
5135 -- run-time packages). This also prevents inconsistencies in the
5136 -- messages for certain ACVC B tests, which can vary depending on
5137 -- types declared in run-time interfaces. Another improvement when
5138 -- aggregates are present is to look for a well-typed operand.
5140 elsif Present (Candidate_Type)
5141 and then (Nkind (N) /= N_Op_Concat
5142 or else Is_Array_Type (Etype (L))
5143 or else Is_Array_Type (Etype (R)))
5146 if Nkind (N) = N_Op_Concat then
5147 if Etype (L) /= Any_Composite
5148 and then Is_Array_Type (Etype (L))
5150 Candidate_Type := Etype (L);
5152 elsif Etype (R) /= Any_Composite
5153 and then Is_Array_Type (Etype (R))
5155 Candidate_Type := Etype (R);
5160 ("operator for} is not directly visible!",
5161 N, First_Subtype (Candidate_Type));
5162 Error_Msg_N ("use clause would make operation legal!", N);
5165 -- If either operand is a junk operand (e.g. package name), then
5166 -- post appropriate error messages, but do not complain further.
5168 -- Note that the use of OR in this test instead of OR ELSE is
5169 -- quite deliberate, we may as well check both operands in the
5170 -- binary operator case.
5172 elsif Junk_Operand (R)
5173 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5177 -- If we have a logical operator, one of whose operands is
5178 -- Boolean, then we know that the other operand cannot resolve to
5179 -- Boolean (since we got no interpretations), but in that case we
5180 -- pretty much know that the other operand should be Boolean, so
5181 -- resolve it that way (generating an error)
5183 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5184 if Etype (L) = Standard_Boolean then
5185 Resolve (R, Standard_Boolean);
5187 elsif Etype (R) = Standard_Boolean then
5188 Resolve (L, Standard_Boolean);
5192 -- For an arithmetic operator or comparison operator, if one
5193 -- of the operands is numeric, then we know the other operand
5194 -- is not the same numeric type. If it is a non-numeric type,
5195 -- then probably it is intended to match the other operand.
5197 elsif Nkind_In (N, N_Op_Add,
5203 Nkind_In (N, N_Op_Lt,
5209 if Is_Numeric_Type (Etype (L))
5210 and then not Is_Numeric_Type (Etype (R))
5212 Resolve (R, Etype (L));
5215 elsif Is_Numeric_Type (Etype (R))
5216 and then not Is_Numeric_Type (Etype (L))
5218 Resolve (L, Etype (R));
5222 -- Comparisons on A'Access are common enough to deserve a
5225 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5226 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5227 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5230 ("two access attributes cannot be compared directly", N);
5232 ("\use qualified expression for one of the operands",
5236 -- Another one for C programmers
5238 elsif Nkind (N) = N_Op_Concat
5239 and then Valid_Boolean_Arg (Etype (L))
5240 and then Valid_Boolean_Arg (Etype (R))
5242 Error_Msg_N ("invalid operands for concatenation", N);
5243 Error_Msg_N -- CODEFIX
5244 ("\maybe AND was meant", N);
5247 -- A special case for comparison of access parameter with null
5249 elsif Nkind (N) = N_Op_Eq
5250 and then Is_Entity_Name (L)
5251 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5252 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5254 and then Nkind (R) = N_Null
5256 Error_Msg_N ("access parameter is not allowed to be null", L);
5257 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5260 -- Another special case for exponentiation, where the right
5261 -- operand must be Natural, independently of the base.
5263 elsif Nkind (N) = N_Op_Expon
5264 and then Is_Numeric_Type (Etype (L))
5265 and then not Is_Overloaded (R)
5267 First_Subtype (Base_Type (Etype (R))) /= Standard_Integer
5268 and then Base_Type (Etype (R)) /= Universal_Integer
5271 ("exponent must be of type Natural, found}", R, Etype (R));
5275 -- If we fall through then just give general message. Note that in
5276 -- the following messages, if the operand is overloaded we choose
5277 -- an arbitrary type to complain about, but that is probably more
5278 -- useful than not giving a type at all.
5280 if Nkind (N) in N_Unary_Op then
5281 Error_Msg_Node_2 := Etype (R);
5282 Error_Msg_N ("operator& not defined for}", N);
5286 if Nkind (N) in N_Binary_Op then
5287 if not Is_Overloaded (L)
5288 and then not Is_Overloaded (R)
5289 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5291 Error_Msg_Node_2 := First_Subtype (Etype (R));
5292 Error_Msg_N ("there is no applicable operator& for}", N);
5295 -- Another attempt to find a fix: one of the candidate
5296 -- interpretations may not be use-visible. This has
5297 -- already been checked for predefined operators, so
5298 -- we examine only user-defined functions.
5300 Op_Id := Get_Name_Entity_Id (Chars (N));
5302 while Present (Op_Id) loop
5303 if Ekind (Op_Id) /= E_Operator
5304 and then Is_Overloadable (Op_Id)
5306 if not Is_Immediately_Visible (Op_Id)
5307 and then not In_Use (Scope (Op_Id))
5308 and then not Is_Abstract_Subprogram (Op_Id)
5309 and then not Is_Hidden (Op_Id)
5310 and then Ekind (Scope (Op_Id)) = E_Package
5313 (L, Etype (First_Formal (Op_Id)))
5315 (Next_Formal (First_Formal (Op_Id)))
5319 Etype (Next_Formal (First_Formal (Op_Id))))
5322 ("No legal interpretation for operator&", N);
5324 ("\use clause on& would make operation legal",
5330 Op_Id := Homonym (Op_Id);
5334 Error_Msg_N ("invalid operand types for operator&", N);
5336 if Nkind (N) /= N_Op_Concat then
5337 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5338 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5348 -----------------------------------------
5349 -- Process_Implicit_Dereference_Prefix --
5350 -----------------------------------------
5352 function Process_Implicit_Dereference_Prefix
5354 P : Entity_Id) return Entity_Id
5357 Typ : constant Entity_Id := Designated_Type (Etype (P));
5361 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5363 -- We create a dummy reference to E to ensure that the reference
5364 -- is not considered as part of an assignment (an implicit
5365 -- dereference can never assign to its prefix). The Comes_From_Source
5366 -- attribute needs to be propagated for accurate warnings.
5368 Ref := New_Reference_To (E, Sloc (P));
5369 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5370 Generate_Reference (E, Ref);
5373 -- An implicit dereference is a legal occurrence of an
5374 -- incomplete type imported through a limited_with clause,
5375 -- if the full view is visible.
5377 if From_With_Type (Typ)
5378 and then not From_With_Type (Scope (Typ))
5380 (Is_Immediately_Visible (Scope (Typ))
5382 (Is_Child_Unit (Scope (Typ))
5383 and then Is_Visible_Child_Unit (Scope (Typ))))
5385 return Available_View (Typ);
5390 end Process_Implicit_Dereference_Prefix;
5392 --------------------------------
5393 -- Remove_Abstract_Operations --
5394 --------------------------------
5396 procedure Remove_Abstract_Operations (N : Node_Id) is
5397 Abstract_Op : Entity_Id := Empty;
5398 Address_Kludge : Boolean := False;
5402 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5403 -- activate this if either extensions are enabled, or if the abstract
5404 -- operation in question comes from a predefined file. This latter test
5405 -- allows us to use abstract to make operations invisible to users. In
5406 -- particular, if type Address is non-private and abstract subprograms
5407 -- are used to hide its operators, they will be truly hidden.
5409 type Operand_Position is (First_Op, Second_Op);
5410 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5412 procedure Remove_Address_Interpretations (Op : Operand_Position);
5413 -- Ambiguities may arise when the operands are literal and the address
5414 -- operations in s-auxdec are visible. In that case, remove the
5415 -- interpretation of a literal as Address, to retain the semantics of
5416 -- Address as a private type.
5418 ------------------------------------
5419 -- Remove_Address_Interpretations --
5420 ------------------------------------
5422 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5426 if Is_Overloaded (N) then
5427 Get_First_Interp (N, I, It);
5428 while Present (It.Nam) loop
5429 Formal := First_Entity (It.Nam);
5431 if Op = Second_Op then
5432 Formal := Next_Entity (Formal);
5435 if Is_Descendent_Of_Address (Etype (Formal)) then
5436 Address_Kludge := True;
5440 Get_Next_Interp (I, It);
5443 end Remove_Address_Interpretations;
5445 -- Start of processing for Remove_Abstract_Operations
5448 if Is_Overloaded (N) then
5449 Get_First_Interp (N, I, It);
5451 while Present (It.Nam) loop
5452 if Is_Overloadable (It.Nam)
5453 and then Is_Abstract_Subprogram (It.Nam)
5454 and then not Is_Dispatching_Operation (It.Nam)
5456 Abstract_Op := It.Nam;
5458 if Is_Descendent_Of_Address (It.Typ) then
5459 Address_Kludge := True;
5463 -- In Ada 2005, this operation does not participate in Overload
5464 -- resolution. If the operation is defined in a predefined
5465 -- unit, it is one of the operations declared abstract in some
5466 -- variants of System, and it must be removed as well.
5468 elsif Ada_Version >= Ada_05
5469 or else Is_Predefined_File_Name
5470 (Unit_File_Name (Get_Source_Unit (It.Nam)))
5477 Get_Next_Interp (I, It);
5480 if No (Abstract_Op) then
5482 -- If some interpretation yields an integer type, it is still
5483 -- possible that there are address interpretations. Remove them
5484 -- if one operand is a literal, to avoid spurious ambiguities
5485 -- on systems where Address is a visible integer type.
5487 if Is_Overloaded (N)
5488 and then Nkind (N) in N_Op
5489 and then Is_Integer_Type (Etype (N))
5491 if Nkind (N) in N_Binary_Op then
5492 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
5493 Remove_Address_Interpretations (Second_Op);
5495 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
5496 Remove_Address_Interpretations (First_Op);
5501 elsif Nkind (N) in N_Op then
5503 -- Remove interpretations that treat literals as addresses. This
5504 -- is never appropriate, even when Address is defined as a visible
5505 -- Integer type. The reason is that we would really prefer Address
5506 -- to behave as a private type, even in this case, which is there
5507 -- only to accommodate oddities of VMS address sizes. If Address
5508 -- is a visible integer type, we get lots of overload ambiguities.
5510 if Nkind (N) in N_Binary_Op then
5512 U1 : constant Boolean :=
5513 Present (Universal_Interpretation (Right_Opnd (N)));
5514 U2 : constant Boolean :=
5515 Present (Universal_Interpretation (Left_Opnd (N)));
5519 Remove_Address_Interpretations (Second_Op);
5523 Remove_Address_Interpretations (First_Op);
5526 if not (U1 and U2) then
5528 -- Remove corresponding predefined operator, which is
5529 -- always added to the overload set.
5531 Get_First_Interp (N, I, It);
5532 while Present (It.Nam) loop
5533 if Scope (It.Nam) = Standard_Standard
5534 and then Base_Type (It.Typ) =
5535 Base_Type (Etype (Abstract_Op))
5540 Get_Next_Interp (I, It);
5543 elsif Is_Overloaded (N)
5544 and then Present (Univ_Type)
5546 -- If both operands have a universal interpretation,
5547 -- it is still necessary to remove interpretations that
5548 -- yield Address. Any remaining ambiguities will be
5549 -- removed in Disambiguate.
5551 Get_First_Interp (N, I, It);
5552 while Present (It.Nam) loop
5553 if Is_Descendent_Of_Address (It.Typ) then
5556 elsif not Is_Type (It.Nam) then
5557 Set_Entity (N, It.Nam);
5560 Get_Next_Interp (I, It);
5566 elsif Nkind (N) = N_Function_Call
5568 (Nkind (Name (N)) = N_Operator_Symbol
5570 (Nkind (Name (N)) = N_Expanded_Name
5572 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
5576 Arg1 : constant Node_Id := First (Parameter_Associations (N));
5577 U1 : constant Boolean :=
5578 Present (Universal_Interpretation (Arg1));
5579 U2 : constant Boolean :=
5580 Present (Next (Arg1)) and then
5581 Present (Universal_Interpretation (Next (Arg1)));
5585 Remove_Address_Interpretations (First_Op);
5589 Remove_Address_Interpretations (Second_Op);
5592 if not (U1 and U2) then
5593 Get_First_Interp (N, I, It);
5594 while Present (It.Nam) loop
5595 if Scope (It.Nam) = Standard_Standard
5596 and then It.Typ = Base_Type (Etype (Abstract_Op))
5601 Get_Next_Interp (I, It);
5607 -- If the removal has left no valid interpretations, emit an error
5608 -- message now and label node as illegal.
5610 if Present (Abstract_Op) then
5611 Get_First_Interp (N, I, It);
5615 -- Removal of abstract operation left no viable candidate
5617 Set_Etype (N, Any_Type);
5618 Error_Msg_Sloc := Sloc (Abstract_Op);
5620 ("cannot call abstract operation& declared#", N, Abstract_Op);
5622 -- In Ada 2005, an abstract operation may disable predefined
5623 -- operators. Since the context is not yet known, we mark the
5624 -- predefined operators as potentially hidden. Do not include
5625 -- predefined operators when addresses are involved since this
5626 -- case is handled separately.
5628 elsif Ada_Version >= Ada_05
5629 and then not Address_Kludge
5631 while Present (It.Nam) loop
5632 if Is_Numeric_Type (It.Typ)
5633 and then Scope (It.Typ) = Standard_Standard
5635 Set_Abstract_Op (I, Abstract_Op);
5638 Get_Next_Interp (I, It);
5643 end Remove_Abstract_Operations;
5645 -----------------------
5646 -- Try_Indirect_Call --
5647 -----------------------
5649 function Try_Indirect_Call
5652 Typ : Entity_Id) return Boolean
5658 pragma Warnings (Off, Call_OK);
5661 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
5663 Actual := First_Actual (N);
5664 Formal := First_Formal (Designated_Type (Typ));
5665 while Present (Actual) and then Present (Formal) loop
5666 if not Has_Compatible_Type (Actual, Etype (Formal)) then
5671 Next_Formal (Formal);
5674 if No (Actual) and then No (Formal) then
5675 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
5677 -- Nam is a candidate interpretation for the name in the call,
5678 -- if it is not an indirect call.
5680 if not Is_Type (Nam)
5681 and then Is_Entity_Name (Name (N))
5683 Set_Entity (Name (N), Nam);
5690 end Try_Indirect_Call;
5692 ----------------------
5693 -- Try_Indexed_Call --
5694 ----------------------
5696 function Try_Indexed_Call
5700 Skip_First : Boolean) return Boolean
5702 Loc : constant Source_Ptr := Sloc (N);
5703 Actuals : constant List_Id := Parameter_Associations (N);
5708 Actual := First (Actuals);
5710 -- If the call was originally written in prefix form, skip the first
5711 -- actual, which is obviously not defaulted.
5717 Index := First_Index (Typ);
5718 while Present (Actual) and then Present (Index) loop
5720 -- If the parameter list has a named association, the expression
5721 -- is definitely a call and not an indexed component.
5723 if Nkind (Actual) = N_Parameter_Association then
5727 if Is_Entity_Name (Actual)
5728 and then Is_Type (Entity (Actual))
5729 and then No (Next (Actual))
5733 Prefix => Make_Function_Call (Loc,
5734 Name => Relocate_Node (Name (N))),
5736 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
5741 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
5749 if No (Actual) and then No (Index) then
5750 Add_One_Interp (N, Nam, Component_Type (Typ));
5752 -- Nam is a candidate interpretation for the name in the call,
5753 -- if it is not an indirect call.
5755 if not Is_Type (Nam)
5756 and then Is_Entity_Name (Name (N))
5758 Set_Entity (Name (N), Nam);
5765 end Try_Indexed_Call;
5767 --------------------------
5768 -- Try_Object_Operation --
5769 --------------------------
5771 function Try_Object_Operation (N : Node_Id) return Boolean is
5772 K : constant Node_Kind := Nkind (Parent (N));
5773 Is_Subprg_Call : constant Boolean := Nkind_In
5774 (K, N_Procedure_Call_Statement,
5776 Loc : constant Source_Ptr := Sloc (N);
5777 Obj : constant Node_Id := Prefix (N);
5778 Subprog : constant Node_Id :=
5779 Make_Identifier (Sloc (Selector_Name (N)),
5780 Chars => Chars (Selector_Name (N)));
5781 -- Identifier on which possible interpretations will be collected
5783 Report_Error : Boolean := False;
5784 -- If no candidate interpretation matches the context, redo the
5785 -- analysis with error enabled to provide additional information.
5788 Candidate : Entity_Id := Empty;
5789 New_Call_Node : Node_Id := Empty;
5790 Node_To_Replace : Node_Id;
5791 Obj_Type : Entity_Id := Etype (Obj);
5792 Success : Boolean := False;
5794 function Valid_Candidate
5797 Subp : Entity_Id) return Entity_Id;
5798 -- If the subprogram is a valid interpretation, record it, and add
5799 -- to the list of interpretations of Subprog.
5801 procedure Complete_Object_Operation
5802 (Call_Node : Node_Id;
5803 Node_To_Replace : Node_Id);
5804 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
5805 -- Call_Node, insert the object (or its dereference) as the first actual
5806 -- in the call, and complete the analysis of the call.
5808 procedure Report_Ambiguity (Op : Entity_Id);
5809 -- If a prefixed procedure call is ambiguous, indicate whether the
5810 -- call includes an implicit dereference or an implicit 'Access.
5812 procedure Transform_Object_Operation
5813 (Call_Node : out Node_Id;
5814 Node_To_Replace : out Node_Id);
5815 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
5816 -- Call_Node is the resulting subprogram call, Node_To_Replace is
5817 -- either N or the parent of N, and Subprog is a reference to the
5818 -- subprogram we are trying to match.
5820 function Try_Class_Wide_Operation
5821 (Call_Node : Node_Id;
5822 Node_To_Replace : Node_Id) return Boolean;
5823 -- Traverse all ancestor types looking for a class-wide subprogram
5824 -- for which the current operation is a valid non-dispatching call.
5826 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
5827 -- If prefix is overloaded, its interpretation may include different
5828 -- tagged types, and we must examine the primitive operations and
5829 -- the class-wide operations of each in order to find candidate
5830 -- interpretations for the call as a whole.
5832 function Try_Primitive_Operation
5833 (Call_Node : Node_Id;
5834 Node_To_Replace : Node_Id) return Boolean;
5835 -- Traverse the list of primitive subprograms looking for a dispatching
5836 -- operation for which the current node is a valid call .
5838 ---------------------
5839 -- Valid_Candidate --
5840 ---------------------
5842 function Valid_Candidate
5845 Subp : Entity_Id) return Entity_Id
5847 Arr_Type : Entity_Id;
5848 Comp_Type : Entity_Id;
5851 -- If the subprogram is a valid interpretation, record it in global
5852 -- variable Subprog, to collect all possible overloadings.
5855 if Subp /= Entity (Subprog) then
5856 Add_One_Interp (Subprog, Subp, Etype (Subp));
5860 -- If the call may be an indexed call, retrieve component type of
5861 -- resulting expression, and add possible interpretation.
5866 if Nkind (Call) = N_Function_Call
5867 and then Nkind (Parent (N)) = N_Indexed_Component
5868 and then Needs_One_Actual (Subp)
5870 if Is_Array_Type (Etype (Subp)) then
5871 Arr_Type := Etype (Subp);
5873 elsif Is_Access_Type (Etype (Subp))
5874 and then Is_Array_Type (Designated_Type (Etype (Subp)))
5876 Arr_Type := Designated_Type (Etype (Subp));
5880 if Present (Arr_Type) then
5882 -- Verify that the actuals (excluding the object)
5883 -- match the types of the indices.
5890 Actual := Next (First_Actual (Call));
5891 Index := First_Index (Arr_Type);
5892 while Present (Actual) and then Present (Index) loop
5893 if not Has_Compatible_Type (Actual, Etype (Index)) then
5898 Next_Actual (Actual);
5904 and then Present (Arr_Type)
5906 Comp_Type := Component_Type (Arr_Type);
5910 if Present (Comp_Type)
5911 and then Etype (Subprog) /= Comp_Type
5913 Add_One_Interp (Subprog, Subp, Comp_Type);
5917 if Etype (Call) /= Any_Type then
5922 end Valid_Candidate;
5924 -------------------------------
5925 -- Complete_Object_Operation --
5926 -------------------------------
5928 procedure Complete_Object_Operation
5929 (Call_Node : Node_Id;
5930 Node_To_Replace : Node_Id)
5932 Control : constant Entity_Id := First_Formal (Entity (Subprog));
5933 Formal_Type : constant Entity_Id := Etype (Control);
5934 First_Actual : Node_Id;
5937 -- Place the name of the operation, with its interpretations,
5938 -- on the rewritten call.
5940 Set_Name (Call_Node, Subprog);
5942 First_Actual := First (Parameter_Associations (Call_Node));
5944 -- For cross-reference purposes, treat the new node as being in
5945 -- the source if the original one is.
5947 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
5948 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
5950 if Nkind (N) = N_Selected_Component
5951 and then not Inside_A_Generic
5953 Set_Entity (Selector_Name (N), Entity (Subprog));
5956 -- If need be, rewrite first actual as an explicit dereference
5957 -- If the call is overloaded, the rewriting can only be done
5958 -- once the primitive operation is identified.
5960 if Is_Overloaded (Subprog) then
5962 -- The prefix itself may be overloaded, and its interpretations
5963 -- must be propagated to the new actual in the call.
5965 if Is_Overloaded (Obj) then
5966 Save_Interps (Obj, First_Actual);
5969 Rewrite (First_Actual, Obj);
5971 elsif not Is_Access_Type (Formal_Type)
5972 and then Is_Access_Type (Etype (Obj))
5974 Rewrite (First_Actual,
5975 Make_Explicit_Dereference (Sloc (Obj), Obj));
5976 Analyze (First_Actual);
5978 -- If we need to introduce an explicit dereference, verify that
5979 -- the resulting actual is compatible with the mode of the formal.
5981 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
5982 and then Is_Access_Constant (Etype (Obj))
5985 ("expect variable in call to&", Prefix (N), Entity (Subprog));
5988 -- Conversely, if the formal is an access parameter and the object
5989 -- is not, replace the actual with a 'Access reference. Its analysis
5990 -- will check that the object is aliased.
5992 elsif Is_Access_Type (Formal_Type)
5993 and then not Is_Access_Type (Etype (Obj))
5995 -- A special case: A.all'access is illegal if A is an access to a
5996 -- constant and the context requires an access to a variable.
5998 if not Is_Access_Constant (Formal_Type) then
5999 if (Nkind (Obj) = N_Explicit_Dereference
6000 and then Is_Access_Constant (Etype (Prefix (Obj))))
6001 or else not Is_Variable (Obj)
6004 ("actual for& must be a variable", Obj, Control);
6008 Rewrite (First_Actual,
6009 Make_Attribute_Reference (Loc,
6010 Attribute_Name => Name_Access,
6011 Prefix => Relocate_Node (Obj)));
6013 if not Is_Aliased_View (Obj) then
6015 ("object in prefixed call to& must be aliased"
6016 & " (RM-2005 4.3.1 (13))",
6017 Prefix (First_Actual), Subprog);
6020 Analyze (First_Actual);
6023 if Is_Overloaded (Obj) then
6024 Save_Interps (Obj, First_Actual);
6027 Rewrite (First_Actual, Obj);
6030 Rewrite (Node_To_Replace, Call_Node);
6032 -- Propagate the interpretations collected in subprog to the new
6033 -- function call node, to be resolved from context.
6035 if Is_Overloaded (Subprog) then
6036 Save_Interps (Subprog, Node_To_Replace);
6038 Analyze (Node_To_Replace);
6040 end Complete_Object_Operation;
6042 ----------------------
6043 -- Report_Ambiguity --
6044 ----------------------
6046 procedure Report_Ambiguity (Op : Entity_Id) is
6047 Access_Formal : constant Boolean :=
6048 Is_Access_Type (Etype (First_Formal (Op)));
6049 Access_Actual : constant Boolean :=
6050 Is_Access_Type (Etype (Prefix (N)));
6053 Error_Msg_Sloc := Sloc (Op);
6055 if Access_Formal and then not Access_Actual then
6056 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6058 ("\possible interpretation"
6059 & " (inherited, with implicit 'Access) #", N);
6062 ("\possible interpretation (with implicit 'Access) #", N);
6065 elsif not Access_Formal and then Access_Actual then
6066 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6068 ("\possible interpretation"
6069 & " ( inherited, with implicit dereference) #", N);
6072 ("\possible interpretation (with implicit dereference) #", N);
6076 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6077 Error_Msg_N ("\possible interpretation (inherited)#", N);
6079 Error_Msg_N -- CODEFIX
6080 ("\possible interpretation#", N);
6083 end Report_Ambiguity;
6085 --------------------------------
6086 -- Transform_Object_Operation --
6087 --------------------------------
6089 procedure Transform_Object_Operation
6090 (Call_Node : out Node_Id;
6091 Node_To_Replace : out Node_Id)
6093 Dummy : constant Node_Id := New_Copy (Obj);
6094 -- Placeholder used as a first parameter in the call, replaced
6095 -- eventually by the proper object.
6097 Parent_Node : constant Node_Id := Parent (N);
6103 -- Common case covering 1) Call to a procedure and 2) Call to a
6104 -- function that has some additional actuals.
6106 if Nkind_In (Parent_Node, N_Function_Call,
6107 N_Procedure_Call_Statement)
6109 -- N is a selected component node containing the name of the
6110 -- subprogram. If N is not the name of the parent node we must
6111 -- not replace the parent node by the new construct. This case
6112 -- occurs when N is a parameterless call to a subprogram that
6113 -- is an actual parameter of a call to another subprogram. For
6115 -- Some_Subprogram (..., Obj.Operation, ...)
6117 and then Name (Parent_Node) = N
6119 Node_To_Replace := Parent_Node;
6121 Actuals := Parameter_Associations (Parent_Node);
6123 if Present (Actuals) then
6124 Prepend (Dummy, Actuals);
6126 Actuals := New_List (Dummy);
6129 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6131 Make_Procedure_Call_Statement (Loc,
6132 Name => New_Copy (Subprog),
6133 Parameter_Associations => Actuals);
6137 Make_Function_Call (Loc,
6138 Name => New_Copy (Subprog),
6139 Parameter_Associations => Actuals);
6143 -- Before analysis, a function call appears as an indexed component
6144 -- if there are no named associations.
6146 elsif Nkind (Parent_Node) = N_Indexed_Component
6147 and then N = Prefix (Parent_Node)
6149 Node_To_Replace := Parent_Node;
6151 Actuals := Expressions (Parent_Node);
6153 Actual := First (Actuals);
6154 while Present (Actual) loop
6159 Prepend (Dummy, Actuals);
6162 Make_Function_Call (Loc,
6163 Name => New_Copy (Subprog),
6164 Parameter_Associations => Actuals);
6166 -- Parameterless call: Obj.F is rewritten as F (Obj)
6169 Node_To_Replace := N;
6172 Make_Function_Call (Loc,
6173 Name => New_Copy (Subprog),
6174 Parameter_Associations => New_List (Dummy));
6176 end Transform_Object_Operation;
6178 ------------------------------
6179 -- Try_Class_Wide_Operation --
6180 ------------------------------
6182 function Try_Class_Wide_Operation
6183 (Call_Node : Node_Id;
6184 Node_To_Replace : Node_Id) return Boolean
6186 Anc_Type : Entity_Id;
6187 Matching_Op : Entity_Id := Empty;
6190 procedure Traverse_Homonyms
6191 (Anc_Type : Entity_Id;
6192 Error : out Boolean);
6193 -- Traverse the homonym chain of the subprogram searching for those
6194 -- homonyms whose first formal has the Anc_Type's class-wide type,
6195 -- or an anonymous access type designating the class-wide type. If
6196 -- an ambiguity is detected, then Error is set to True.
6198 procedure Traverse_Interfaces
6199 (Anc_Type : Entity_Id;
6200 Error : out Boolean);
6201 -- Traverse the list of interfaces, if any, associated with Anc_Type
6202 -- and search for acceptable class-wide homonyms associated with each
6203 -- interface. If an ambiguity is detected, then Error is set to True.
6205 -----------------------
6206 -- Traverse_Homonyms --
6207 -----------------------
6209 procedure Traverse_Homonyms
6210 (Anc_Type : Entity_Id;
6211 Error : out Boolean)
6213 Cls_Type : Entity_Id;
6221 Cls_Type := Class_Wide_Type (Anc_Type);
6223 Hom := Current_Entity (Subprog);
6225 -- Find operation whose first parameter is of the class-wide
6226 -- type, a subtype thereof, or an anonymous access to same.
6228 while Present (Hom) loop
6229 if (Ekind (Hom) = E_Procedure
6231 Ekind (Hom) = E_Function)
6232 and then Scope (Hom) = Scope (Anc_Type)
6233 and then Present (First_Formal (Hom))
6235 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6237 (Is_Access_Type (Etype (First_Formal (Hom)))
6239 Ekind (Etype (First_Formal (Hom))) =
6240 E_Anonymous_Access_Type
6243 (Designated_Type (Etype (First_Formal (Hom)))) =
6246 Set_Etype (Call_Node, Any_Type);
6247 Set_Is_Overloaded (Call_Node, False);
6250 if No (Matching_Op) then
6251 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6252 Set_Etype (Call_Node, Any_Type);
6253 Set_Parent (Call_Node, Parent (Node_To_Replace));
6255 Set_Name (Call_Node, Hom_Ref);
6260 Report => Report_Error,
6262 Skip_First => True);
6265 Valid_Candidate (Success, Call_Node, Hom);
6271 Report => Report_Error,
6273 Skip_First => True);
6275 if Present (Valid_Candidate (Success, Call_Node, Hom))
6276 and then Nkind (Call_Node) /= N_Function_Call
6278 Error_Msg_NE ("ambiguous call to&", N, Hom);
6279 Report_Ambiguity (Matching_Op);
6280 Report_Ambiguity (Hom);
6287 Hom := Homonym (Hom);
6289 end Traverse_Homonyms;
6291 -------------------------
6292 -- Traverse_Interfaces --
6293 -------------------------
6295 procedure Traverse_Interfaces
6296 (Anc_Type : Entity_Id;
6297 Error : out Boolean)
6299 Intface_List : constant List_Id :=
6300 Abstract_Interface_List (Anc_Type);
6306 if Is_Non_Empty_List (Intface_List) then
6307 Intface := First (Intface_List);
6308 while Present (Intface) loop
6310 -- Look for acceptable class-wide homonyms associated with
6313 Traverse_Homonyms (Etype (Intface), Error);
6319 -- Continue the search by looking at each of the interface's
6320 -- associated interface ancestors.
6322 Traverse_Interfaces (Etype (Intface), Error);
6331 end Traverse_Interfaces;
6333 -- Start of processing for Try_Class_Wide_Operation
6336 -- Loop through ancestor types (including interfaces), traversing
6337 -- the homonym chain of the subprogram, trying out those homonyms
6338 -- whose first formal has the class-wide type of the ancestor, or
6339 -- an anonymous access type designating the class-wide type.
6341 Anc_Type := Obj_Type;
6343 -- Look for a match among homonyms associated with the ancestor
6345 Traverse_Homonyms (Anc_Type, Error);
6351 -- Continue the search for matches among homonyms associated with
6352 -- any interfaces implemented by the ancestor.
6354 Traverse_Interfaces (Anc_Type, Error);
6360 exit when Etype (Anc_Type) = Anc_Type;
6361 Anc_Type := Etype (Anc_Type);
6364 if Present (Matching_Op) then
6365 Set_Etype (Call_Node, Etype (Matching_Op));
6368 return Present (Matching_Op);
6369 end Try_Class_Wide_Operation;
6371 -----------------------------------
6372 -- Try_One_Prefix_Interpretation --
6373 -----------------------------------
6375 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6379 if Is_Access_Type (Obj_Type) then
6380 Obj_Type := Designated_Type (Obj_Type);
6383 if Ekind (Obj_Type) = E_Private_Subtype then
6384 Obj_Type := Base_Type (Obj_Type);
6387 if Is_Class_Wide_Type (Obj_Type) then
6388 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6391 -- The type may have be obtained through a limited_with clause,
6392 -- in which case the primitive operations are available on its
6393 -- non-limited view. If still incomplete, retrieve full view.
6395 if Ekind (Obj_Type) = E_Incomplete_Type
6396 and then From_With_Type (Obj_Type)
6398 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6401 -- If the object is not tagged, or the type is still an incomplete
6402 -- type, this is not a prefixed call.
6404 if not Is_Tagged_Type (Obj_Type)
6405 or else Is_Incomplete_Type (Obj_Type)
6410 if Try_Primitive_Operation
6411 (Call_Node => New_Call_Node,
6412 Node_To_Replace => Node_To_Replace)
6414 Try_Class_Wide_Operation
6415 (Call_Node => New_Call_Node,
6416 Node_To_Replace => Node_To_Replace)
6420 end Try_One_Prefix_Interpretation;
6422 -----------------------------
6423 -- Try_Primitive_Operation --
6424 -----------------------------
6426 function Try_Primitive_Operation
6427 (Call_Node : Node_Id;
6428 Node_To_Replace : Node_Id) return Boolean
6431 Prim_Op : Entity_Id;
6432 Matching_Op : Entity_Id := Empty;
6433 Prim_Op_Ref : Node_Id := Empty;
6435 Corr_Type : Entity_Id := Empty;
6436 -- If the prefix is a synchronized type, the controlling type of
6437 -- the primitive operation is the corresponding record type, else
6438 -- this is the object type itself.
6440 Success : Boolean := False;
6442 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
6443 -- For tagged types the candidate interpretations are found in
6444 -- the list of primitive operations of the type and its ancestors.
6445 -- For formal tagged types we have to find the operations declared
6446 -- in the same scope as the type (including in the generic formal
6447 -- part) because the type itself carries no primitive operations,
6448 -- except for formal derived types that inherit the operations of
6449 -- the parent and progenitors.
6450 -- If the context is a generic subprogram body, the generic formals
6451 -- are visible by name, but are not in the entity list of the
6452 -- subprogram because that list starts with the subprogram formals.
6453 -- We retrieve the candidate operations from the generic declaration.
6455 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
6456 -- Verify that the prefix, dereferenced if need be, is a valid
6457 -- controlling argument in a call to Op. The remaining actuals
6458 -- are checked in the subsequent call to Analyze_One_Call.
6460 ------------------------------
6461 -- Collect_Generic_Type_Ops --
6462 ------------------------------
6464 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
6465 Bas : constant Entity_Id := Base_Type (T);
6466 Candidates : constant Elist_Id := New_Elmt_List;
6470 procedure Check_Candidate;
6471 -- The operation is a candidate if its first parameter is a
6472 -- controlling operand of the desired type.
6474 -----------------------
6475 -- Check_Candidate; --
6476 -----------------------
6478 procedure Check_Candidate is
6480 Formal := First_Formal (Subp);
6483 and then Is_Controlling_Formal (Formal)
6485 (Base_Type (Etype (Formal)) = Bas
6487 (Is_Access_Type (Etype (Formal))
6488 and then Designated_Type (Etype (Formal)) = Bas))
6490 Append_Elmt (Subp, Candidates);
6492 end Check_Candidate;
6494 -- Start of processing for Collect_Generic_Type_Ops
6497 if Is_Derived_Type (T) then
6498 return Primitive_Operations (T);
6500 elsif Ekind (Scope (T)) = E_Procedure
6501 or else Ekind (Scope (T)) = E_Function
6503 -- Scan the list of generic formals to find subprograms
6504 -- that may have a first controlling formal of the type.
6511 First (Generic_Formal_Declarations
6512 (Unit_Declaration_Node (Scope (T))));
6513 while Present (Decl) loop
6514 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
6515 Subp := Defining_Entity (Decl);
6526 -- Scan the list of entities declared in the same scope as
6527 -- the type. In general this will be an open scope, given that
6528 -- the call we are analyzing can only appear within a generic
6529 -- declaration or body (either the one that declares T, or a
6532 Subp := First_Entity (Scope (T));
6533 while Present (Subp) loop
6534 if Is_Overloadable (Subp) then
6543 end Collect_Generic_Type_Ops;
6545 -----------------------------
6546 -- Valid_First_Argument_Of --
6547 -----------------------------
6549 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
6550 Typ : Entity_Id := Etype (First_Formal (Op));
6553 if Is_Concurrent_Type (Typ)
6554 and then Present (Corresponding_Record_Type (Typ))
6556 Typ := Corresponding_Record_Type (Typ);
6559 -- Simple case. Object may be a subtype of the tagged type or
6560 -- may be the corresponding record of a synchronized type.
6562 return Obj_Type = Typ
6563 or else Base_Type (Obj_Type) = Typ
6564 or else Corr_Type = Typ
6566 -- Prefix can be dereferenced
6569 (Is_Access_Type (Corr_Type)
6570 and then Designated_Type (Corr_Type) = Typ)
6572 -- Formal is an access parameter, for which the object
6573 -- can provide an access.
6576 (Ekind (Typ) = E_Anonymous_Access_Type
6577 and then Designated_Type (Typ) = Base_Type (Corr_Type));
6578 end Valid_First_Argument_Of;
6580 -- Start of processing for Try_Primitive_Operation
6583 -- Look for subprograms in the list of primitive operations. The name
6584 -- must be identical, and the kind of call indicates the expected
6585 -- kind of operation (function or procedure). If the type is a
6586 -- (tagged) synchronized type, the primitive ops are attached to the
6587 -- corresponding record (base) type.
6589 if Is_Concurrent_Type (Obj_Type) then
6590 if not Present (Corresponding_Record_Type (Obj_Type)) then
6594 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
6595 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
6597 elsif not Is_Generic_Type (Obj_Type) then
6598 Corr_Type := Obj_Type;
6599 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
6602 Corr_Type := Obj_Type;
6603 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
6606 while Present (Elmt) loop
6607 Prim_Op := Node (Elmt);
6609 if Chars (Prim_Op) = Chars (Subprog)
6610 and then Present (First_Formal (Prim_Op))
6611 and then Valid_First_Argument_Of (Prim_Op)
6613 (Nkind (Call_Node) = N_Function_Call)
6614 = (Ekind (Prim_Op) = E_Function)
6616 -- Ada 2005 (AI-251): If this primitive operation corresponds
6617 -- with an immediate ancestor interface there is no need to add
6618 -- it to the list of interpretations; the corresponding aliased
6619 -- primitive is also in this list of primitive operations and
6620 -- will be used instead.
6622 if (Present (Interface_Alias (Prim_Op))
6623 and then Is_Ancestor (Find_Dispatching_Type
6624 (Alias (Prim_Op)), Corr_Type))
6627 -- Do not consider hidden primitives unless the type is
6628 -- in an open scope or we are within an instance, where
6629 -- visibility is known to be correct.
6631 (Is_Hidden (Prim_Op)
6632 and then not Is_Immediately_Visible (Obj_Type)
6633 and then not In_Instance)
6638 Set_Etype (Call_Node, Any_Type);
6639 Set_Is_Overloaded (Call_Node, False);
6641 if No (Matching_Op) then
6642 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
6643 Candidate := Prim_Op;
6645 Set_Parent (Call_Node, Parent (Node_To_Replace));
6647 Set_Name (Call_Node, Prim_Op_Ref);
6653 Report => Report_Error,
6655 Skip_First => True);
6657 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
6659 -- More than one interpretation, collect for subsequent
6660 -- disambiguation. If this is a procedure call and there
6661 -- is another match, report ambiguity now.
6667 Report => Report_Error,
6669 Skip_First => True);
6671 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
6672 and then Nkind (Call_Node) /= N_Function_Call
6674 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
6675 Report_Ambiguity (Matching_Op);
6676 Report_Ambiguity (Prim_Op);
6686 if Present (Matching_Op) then
6687 Set_Etype (Call_Node, Etype (Matching_Op));
6690 return Present (Matching_Op);
6691 end Try_Primitive_Operation;
6693 -- Start of processing for Try_Object_Operation
6696 Analyze_Expression (Obj);
6698 -- Analyze the actuals if node is known to be a subprogram call
6700 if Is_Subprg_Call and then N = Name (Parent (N)) then
6701 Actual := First (Parameter_Associations (Parent (N)));
6702 while Present (Actual) loop
6703 Analyze_Expression (Actual);
6708 -- Build a subprogram call node, using a copy of Obj as its first
6709 -- actual. This is a placeholder, to be replaced by an explicit
6710 -- dereference when needed.
6712 Transform_Object_Operation
6713 (Call_Node => New_Call_Node,
6714 Node_To_Replace => Node_To_Replace);
6716 Set_Etype (New_Call_Node, Any_Type);
6717 Set_Etype (Subprog, Any_Type);
6718 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
6720 if not Is_Overloaded (Obj) then
6721 Try_One_Prefix_Interpretation (Obj_Type);
6728 Get_First_Interp (Obj, I, It);
6729 while Present (It.Nam) loop
6730 Try_One_Prefix_Interpretation (It.Typ);
6731 Get_Next_Interp (I, It);
6736 if Etype (New_Call_Node) /= Any_Type then
6737 Complete_Object_Operation
6738 (Call_Node => New_Call_Node,
6739 Node_To_Replace => Node_To_Replace);
6742 elsif Present (Candidate) then
6744 -- The argument list is not type correct. Re-analyze with error
6745 -- reporting enabled, and use one of the possible candidates.
6746 -- In All_Errors_Mode, re-analyze all failed interpretations.
6748 if All_Errors_Mode then
6749 Report_Error := True;
6750 if Try_Primitive_Operation
6751 (Call_Node => New_Call_Node,
6752 Node_To_Replace => Node_To_Replace)
6755 Try_Class_Wide_Operation
6756 (Call_Node => New_Call_Node,
6757 Node_To_Replace => Node_To_Replace)
6764 (N => New_Call_Node,
6768 Skip_First => True);
6771 -- No need for further errors
6776 -- There was no candidate operation, so report it as an error
6777 -- in the caller: Analyze_Selected_Component.
6781 end Try_Object_Operation;
6787 procedure wpo (T : Entity_Id) is
6792 if not Is_Tagged_Type (T) then
6796 E := First_Elmt (Primitive_Operations (Base_Type (T)));
6797 while Present (E) loop
6799 Write_Int (Int (Op));
6800 Write_Str (" === ");
6801 Write_Name (Chars (Op));
6803 Write_Name (Chars (Scope (Op)));