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 (Type_Id, 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);
1242 if Comes_From_Source (N) then
1243 Check_Compiler_Unit (N);
1246 Analyze_Expression (Condition);
1247 Analyze_Expression (Then_Expr);
1249 if Present (Else_Expr) then
1250 Analyze_Expression (Else_Expr);
1253 if not Is_Overloaded (Then_Expr) then
1254 Set_Etype (N, Etype (Then_Expr));
1261 Set_Etype (N, Any_Type);
1262 Get_First_Interp (Then_Expr, I, It);
1263 while Present (It.Nam) loop
1264 if Has_Compatible_Type (Else_Expr, It.Typ) then
1265 Add_One_Interp (N, It.Typ, It.Typ);
1268 Get_Next_Interp (I, It);
1272 end Analyze_Conditional_Expression;
1274 -------------------------
1275 -- Analyze_Equality_Op --
1276 -------------------------
1278 procedure Analyze_Equality_Op (N : Node_Id) is
1279 Loc : constant Source_Ptr := Sloc (N);
1280 L : constant Node_Id := Left_Opnd (N);
1281 R : constant Node_Id := Right_Opnd (N);
1285 Set_Etype (N, Any_Type);
1286 Candidate_Type := Empty;
1288 Analyze_Expression (L);
1289 Analyze_Expression (R);
1291 -- If the entity is set, the node is a generic instance with a non-local
1292 -- reference to the predefined operator or to a user-defined function.
1293 -- It can also be an inequality that is expanded into the negation of a
1294 -- call to a user-defined equality operator.
1296 -- For the predefined case, the result is Boolean, regardless of the
1297 -- type of the operands. The operands may even be limited, if they are
1298 -- generic actuals. If they are overloaded, label the left argument with
1299 -- the common type that must be present, or with the type of the formal
1300 -- of the user-defined function.
1302 if Present (Entity (N)) then
1303 Op_Id := Entity (N);
1305 if Ekind (Op_Id) = E_Operator then
1306 Add_One_Interp (N, Op_Id, Standard_Boolean);
1308 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1311 if Is_Overloaded (L) then
1312 if Ekind (Op_Id) = E_Operator then
1313 Set_Etype (L, Intersect_Types (L, R));
1315 Set_Etype (L, Etype (First_Formal (Op_Id)));
1320 Op_Id := Get_Name_Entity_Id (Chars (N));
1321 while Present (Op_Id) loop
1322 if Ekind (Op_Id) = E_Operator then
1323 Find_Equality_Types (L, R, Op_Id, N);
1325 Analyze_User_Defined_Binary_Op (N, Op_Id);
1328 Op_Id := Homonym (Op_Id);
1332 -- If there was no match, and the operator is inequality, this may
1333 -- be a case where inequality has not been made explicit, as for
1334 -- tagged types. Analyze the node as the negation of an equality
1335 -- operation. This cannot be done earlier, because before analysis
1336 -- we cannot rule out the presence of an explicit inequality.
1338 if Etype (N) = Any_Type
1339 and then Nkind (N) = N_Op_Ne
1341 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1342 while Present (Op_Id) loop
1343 if Ekind (Op_Id) = E_Operator then
1344 Find_Equality_Types (L, R, Op_Id, N);
1346 Analyze_User_Defined_Binary_Op (N, Op_Id);
1349 Op_Id := Homonym (Op_Id);
1352 if Etype (N) /= Any_Type then
1353 Op_Id := Entity (N);
1359 Left_Opnd => Left_Opnd (N),
1360 Right_Opnd => Right_Opnd (N))));
1362 Set_Entity (Right_Opnd (N), Op_Id);
1368 end Analyze_Equality_Op;
1370 ----------------------------------
1371 -- Analyze_Explicit_Dereference --
1372 ----------------------------------
1374 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1375 Loc : constant Source_Ptr := Sloc (N);
1376 P : constant Node_Id := Prefix (N);
1382 function Is_Function_Type return Boolean;
1383 -- Check whether node may be interpreted as an implicit function call
1385 ----------------------
1386 -- Is_Function_Type --
1387 ----------------------
1389 function Is_Function_Type return Boolean is
1394 if not Is_Overloaded (N) then
1395 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1396 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1399 Get_First_Interp (N, I, It);
1400 while Present (It.Nam) loop
1401 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1402 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1407 Get_Next_Interp (I, It);
1412 end Is_Function_Type;
1414 -- Start of processing for Analyze_Explicit_Dereference
1418 Set_Etype (N, Any_Type);
1420 -- Test for remote access to subprogram type, and if so return
1421 -- after rewriting the original tree.
1423 if Remote_AST_E_Dereference (P) then
1427 -- Normal processing for other than remote access to subprogram type
1429 if not Is_Overloaded (P) then
1430 if Is_Access_Type (Etype (P)) then
1432 -- Set the Etype. We need to go through Is_For_Access_Subtypes to
1433 -- avoid other problems caused by the Private_Subtype and it is
1434 -- safe to go to the Base_Type because this is the same as
1435 -- converting the access value to its Base_Type.
1438 DT : Entity_Id := Designated_Type (Etype (P));
1441 if Ekind (DT) = E_Private_Subtype
1442 and then Is_For_Access_Subtype (DT)
1444 DT := Base_Type (DT);
1447 -- An explicit dereference is a legal occurrence of an
1448 -- incomplete type imported through a limited_with clause,
1449 -- if the full view is visible.
1451 if From_With_Type (DT)
1452 and then not From_With_Type (Scope (DT))
1454 (Is_Immediately_Visible (Scope (DT))
1456 (Is_Child_Unit (Scope (DT))
1457 and then Is_Visible_Child_Unit (Scope (DT))))
1459 Set_Etype (N, Available_View (DT));
1466 elsif Etype (P) /= Any_Type then
1467 Error_Msg_N ("prefix of dereference must be an access type", N);
1472 Get_First_Interp (P, I, It);
1473 while Present (It.Nam) loop
1476 if Is_Access_Type (T) then
1477 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1480 Get_Next_Interp (I, It);
1483 -- Error if no interpretation of the prefix has an access type
1485 if Etype (N) = Any_Type then
1487 ("access type required in prefix of explicit dereference", P);
1488 Set_Etype (N, Any_Type);
1494 and then Nkind (Parent (N)) /= N_Indexed_Component
1496 and then (Nkind (Parent (N)) /= N_Function_Call
1497 or else N /= Name (Parent (N)))
1499 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1500 or else N /= Name (Parent (N)))
1502 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1503 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1505 (Attribute_Name (Parent (N)) /= Name_Address
1507 Attribute_Name (Parent (N)) /= Name_Access))
1509 -- Name is a function call with no actuals, in a context that
1510 -- requires deproceduring (including as an actual in an enclosing
1511 -- function or procedure call). There are some pathological cases
1512 -- where the prefix might include functions that return access to
1513 -- subprograms and others that return a regular type. Disambiguation
1514 -- of those has to take place in Resolve.
1517 Make_Function_Call (Loc,
1518 Name => Make_Explicit_Dereference (Loc, P),
1519 Parameter_Associations => New_List);
1521 -- If the prefix is overloaded, remove operations that have formals,
1522 -- we know that this is a parameterless call.
1524 if Is_Overloaded (P) then
1525 Get_First_Interp (P, I, It);
1526 while Present (It.Nam) loop
1529 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1535 Get_Next_Interp (I, It);
1542 elsif not Is_Function_Type
1543 and then Is_Overloaded (N)
1545 -- The prefix may include access to subprograms and other access
1546 -- types. If the context selects the interpretation that is a
1547 -- function call (not a procedure call) we cannot rewrite the node
1548 -- yet, but we include the result of the call interpretation.
1550 Get_First_Interp (N, I, It);
1551 while Present (It.Nam) loop
1552 if Ekind (Base_Type (It.Typ)) = E_Subprogram_Type
1553 and then Etype (Base_Type (It.Typ)) /= Standard_Void_Type
1554 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
1556 Add_One_Interp (N, Etype (It.Typ), Etype (It.Typ));
1559 Get_Next_Interp (I, It);
1563 -- A value of remote access-to-class-wide must not be dereferenced
1566 Validate_Remote_Access_To_Class_Wide_Type (N);
1567 end Analyze_Explicit_Dereference;
1569 ------------------------
1570 -- Analyze_Expression --
1571 ------------------------
1573 procedure Analyze_Expression (N : Node_Id) is
1576 Check_Parameterless_Call (N);
1577 end Analyze_Expression;
1579 ------------------------------------
1580 -- Analyze_Indexed_Component_Form --
1581 ------------------------------------
1583 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1584 P : constant Node_Id := Prefix (N);
1585 Exprs : constant List_Id := Expressions (N);
1591 procedure Process_Function_Call;
1592 -- Prefix in indexed component form is an overloadable entity,
1593 -- so the node is a function call. Reformat it as such.
1595 procedure Process_Indexed_Component;
1596 -- Prefix in indexed component form is actually an indexed component.
1597 -- This routine processes it, knowing that the prefix is already
1600 procedure Process_Indexed_Component_Or_Slice;
1601 -- An indexed component with a single index may designate a slice if
1602 -- the index is a subtype mark. This routine disambiguates these two
1603 -- cases by resolving the prefix to see if it is a subtype mark.
1605 procedure Process_Overloaded_Indexed_Component;
1606 -- If the prefix of an indexed component is overloaded, the proper
1607 -- interpretation is selected by the index types and the context.
1609 ---------------------------
1610 -- Process_Function_Call --
1611 ---------------------------
1613 procedure Process_Function_Call is
1617 Change_Node (N, N_Function_Call);
1619 Set_Parameter_Associations (N, Exprs);
1621 -- Analyze actuals prior to analyzing the call itself
1623 Actual := First (Parameter_Associations (N));
1624 while Present (Actual) loop
1626 Check_Parameterless_Call (Actual);
1628 -- Move to next actual. Note that we use Next, not Next_Actual
1629 -- here. The reason for this is a bit subtle. If a function call
1630 -- includes named associations, the parser recognizes the node as
1631 -- a call, and it is analyzed as such. If all associations are
1632 -- positional, the parser builds an indexed_component node, and
1633 -- it is only after analysis of the prefix that the construct
1634 -- is recognized as a call, in which case Process_Function_Call
1635 -- rewrites the node and analyzes the actuals. If the list of
1636 -- actuals is malformed, the parser may leave the node as an
1637 -- indexed component (despite the presence of named associations).
1638 -- The iterator Next_Actual is equivalent to Next if the list is
1639 -- positional, but follows the normalized chain of actuals when
1640 -- named associations are present. In this case normalization has
1641 -- not taken place, and actuals remain unanalyzed, which leads to
1642 -- subsequent crashes or loops if there is an attempt to continue
1643 -- analysis of the program.
1649 end Process_Function_Call;
1651 -------------------------------
1652 -- Process_Indexed_Component --
1653 -------------------------------
1655 procedure Process_Indexed_Component is
1657 Array_Type : Entity_Id;
1659 Pent : Entity_Id := Empty;
1662 Exp := First (Exprs);
1664 if Is_Overloaded (P) then
1665 Process_Overloaded_Indexed_Component;
1668 Array_Type := Etype (P);
1670 if Is_Entity_Name (P) then
1672 elsif Nkind (P) = N_Selected_Component
1673 and then Is_Entity_Name (Selector_Name (P))
1675 Pent := Entity (Selector_Name (P));
1678 -- Prefix must be appropriate for an array type, taking into
1679 -- account a possible implicit dereference.
1681 if Is_Access_Type (Array_Type) then
1682 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1683 Array_Type := Process_Implicit_Dereference_Prefix (Pent, P);
1686 if Is_Array_Type (Array_Type) then
1689 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1691 Set_Etype (N, Any_Type);
1693 if not Has_Compatible_Type
1694 (Exp, Entry_Index_Type (Pent))
1696 Error_Msg_N ("invalid index type in entry name", N);
1698 elsif Present (Next (Exp)) then
1699 Error_Msg_N ("too many subscripts in entry reference", N);
1702 Set_Etype (N, Etype (P));
1707 elsif Is_Record_Type (Array_Type)
1708 and then Remote_AST_I_Dereference (P)
1712 elsif Array_Type = Any_Type then
1713 Set_Etype (N, Any_Type);
1716 -- Here we definitely have a bad indexing
1719 if Nkind (Parent (N)) = N_Requeue_Statement
1720 and then Present (Pent) and then Ekind (Pent) = E_Entry
1723 ("REQUEUE does not permit parameters", First (Exprs));
1725 elsif Is_Entity_Name (P)
1726 and then Etype (P) = Standard_Void_Type
1728 Error_Msg_NE ("incorrect use of&", P, Entity (P));
1731 Error_Msg_N ("array type required in indexed component", P);
1734 Set_Etype (N, Any_Type);
1738 Index := First_Index (Array_Type);
1739 while Present (Index) and then Present (Exp) loop
1740 if not Has_Compatible_Type (Exp, Etype (Index)) then
1741 Wrong_Type (Exp, Etype (Index));
1742 Set_Etype (N, Any_Type);
1750 Set_Etype (N, Component_Type (Array_Type));
1752 if Present (Index) then
1754 ("too few subscripts in array reference", First (Exprs));
1756 elsif Present (Exp) then
1757 Error_Msg_N ("too many subscripts in array reference", Exp);
1760 end Process_Indexed_Component;
1762 ----------------------------------------
1763 -- Process_Indexed_Component_Or_Slice --
1764 ----------------------------------------
1766 procedure Process_Indexed_Component_Or_Slice is
1768 Exp := First (Exprs);
1769 while Present (Exp) loop
1770 Analyze_Expression (Exp);
1774 Exp := First (Exprs);
1776 -- If one index is present, and it is a subtype name, then the
1777 -- node denotes a slice (note that the case of an explicit range
1778 -- for a slice was already built as an N_Slice node in the first
1779 -- place, so that case is not handled here).
1781 -- We use a replace rather than a rewrite here because this is one
1782 -- of the cases in which the tree built by the parser is plain wrong.
1785 and then Is_Entity_Name (Exp)
1786 and then Is_Type (Entity (Exp))
1789 Make_Slice (Sloc (N),
1791 Discrete_Range => New_Copy (Exp)));
1794 -- Otherwise (more than one index present, or single index is not
1795 -- a subtype name), then we have the indexed component case.
1798 Process_Indexed_Component;
1800 end Process_Indexed_Component_Or_Slice;
1802 ------------------------------------------
1803 -- Process_Overloaded_Indexed_Component --
1804 ------------------------------------------
1806 procedure Process_Overloaded_Indexed_Component is
1815 Set_Etype (N, Any_Type);
1817 Get_First_Interp (P, I, It);
1818 while Present (It.Nam) loop
1821 if Is_Access_Type (Typ) then
1822 Typ := Designated_Type (Typ);
1823 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1826 if Is_Array_Type (Typ) then
1828 -- Got a candidate: verify that index types are compatible
1830 Index := First_Index (Typ);
1832 Exp := First (Exprs);
1833 while Present (Index) and then Present (Exp) loop
1834 if Has_Compatible_Type (Exp, Etype (Index)) then
1846 if Found and then No (Index) and then No (Exp) then
1848 Etype (Component_Type (Typ)),
1849 Etype (Component_Type (Typ)));
1853 Get_Next_Interp (I, It);
1856 if Etype (N) = Any_Type then
1857 Error_Msg_N ("no legal interpretation for indexed component", N);
1858 Set_Is_Overloaded (N, False);
1862 end Process_Overloaded_Indexed_Component;
1864 -- Start of processing for Analyze_Indexed_Component_Form
1867 -- Get name of array, function or type
1871 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement) then
1873 -- If P is an explicit dereference whose prefix is of a
1874 -- remote access-to-subprogram type, then N has already
1875 -- been rewritten as a subprogram call and analyzed.
1880 pragma Assert (Nkind (N) = N_Indexed_Component);
1882 P_T := Base_Type (Etype (P));
1884 if Is_Entity_Name (P)
1885 or else Nkind (P) = N_Operator_Symbol
1889 if Is_Type (U_N) then
1891 -- Reformat node as a type conversion
1893 E := Remove_Head (Exprs);
1895 if Present (First (Exprs)) then
1897 ("argument of type conversion must be single expression", N);
1900 Change_Node (N, N_Type_Conversion);
1901 Set_Subtype_Mark (N, P);
1903 Set_Expression (N, E);
1905 -- After changing the node, call for the specific Analysis
1906 -- routine directly, to avoid a double call to the expander.
1908 Analyze_Type_Conversion (N);
1912 if Is_Overloadable (U_N) then
1913 Process_Function_Call;
1915 elsif Ekind (Etype (P)) = E_Subprogram_Type
1916 or else (Is_Access_Type (Etype (P))
1918 Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type)
1920 -- Call to access_to-subprogram with possible implicit dereference
1922 Process_Function_Call;
1924 elsif Is_Generic_Subprogram (U_N) then
1926 -- A common beginner's (or C++ templates fan) error
1928 Error_Msg_N ("generic subprogram cannot be called", N);
1929 Set_Etype (N, Any_Type);
1933 Process_Indexed_Component_Or_Slice;
1936 -- If not an entity name, prefix is an expression that may denote
1937 -- an array or an access-to-subprogram.
1940 if Ekind (P_T) = E_Subprogram_Type
1941 or else (Is_Access_Type (P_T)
1943 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
1945 Process_Function_Call;
1947 elsif Nkind (P) = N_Selected_Component
1948 and then Is_Overloadable (Entity (Selector_Name (P)))
1950 Process_Function_Call;
1953 -- Indexed component, slice, or a call to a member of a family
1954 -- entry, which will be converted to an entry call later.
1956 Process_Indexed_Component_Or_Slice;
1959 end Analyze_Indexed_Component_Form;
1961 ------------------------
1962 -- Analyze_Logical_Op --
1963 ------------------------
1965 procedure Analyze_Logical_Op (N : Node_Id) is
1966 L : constant Node_Id := Left_Opnd (N);
1967 R : constant Node_Id := Right_Opnd (N);
1968 Op_Id : Entity_Id := Entity (N);
1971 Set_Etype (N, Any_Type);
1972 Candidate_Type := Empty;
1974 Analyze_Expression (L);
1975 Analyze_Expression (R);
1977 if Present (Op_Id) then
1979 if Ekind (Op_Id) = E_Operator then
1980 Find_Boolean_Types (L, R, Op_Id, N);
1982 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1986 Op_Id := Get_Name_Entity_Id (Chars (N));
1987 while Present (Op_Id) loop
1988 if Ekind (Op_Id) = E_Operator then
1989 Find_Boolean_Types (L, R, Op_Id, N);
1991 Analyze_User_Defined_Binary_Op (N, Op_Id);
1994 Op_Id := Homonym (Op_Id);
1999 end Analyze_Logical_Op;
2001 ---------------------------
2002 -- Analyze_Membership_Op --
2003 ---------------------------
2005 procedure Analyze_Membership_Op (N : Node_Id) is
2006 L : constant Node_Id := Left_Opnd (N);
2007 R : constant Node_Id := Right_Opnd (N);
2009 Index : Interp_Index;
2011 Found : Boolean := False;
2015 procedure Try_One_Interp (T1 : Entity_Id);
2016 -- Routine to try one proposed interpretation. Note that the context
2017 -- of the operation plays no role in resolving the arguments, so that
2018 -- if there is more than one interpretation of the operands that is
2019 -- compatible with a membership test, the operation is ambiguous.
2021 --------------------
2022 -- Try_One_Interp --
2023 --------------------
2025 procedure Try_One_Interp (T1 : Entity_Id) is
2027 if Has_Compatible_Type (R, T1) then
2029 and then Base_Type (T1) /= Base_Type (T_F)
2031 It := Disambiguate (L, I_F, Index, Any_Type);
2033 if It = No_Interp then
2034 Ambiguous_Operands (N);
2035 Set_Etype (L, Any_Type);
2052 procedure Analyze_Set_Membership;
2053 -- If a set of alternatives is present, analyze each and find the
2054 -- common type to which they must all resolve.
2056 ----------------------------
2057 -- Analyze_Set_Membership --
2058 ----------------------------
2060 procedure Analyze_Set_Membership is
2062 Index : Interp_Index;
2064 Candidate_Interps : Node_Id;
2065 Common_Type : Entity_Id := Empty;
2069 Candidate_Interps := L;
2071 if not Is_Overloaded (L) then
2072 Common_Type := Etype (L);
2074 Alt := First (Alternatives (N));
2075 while Present (Alt) loop
2078 if not Has_Compatible_Type (Alt, Common_Type) then
2079 Wrong_Type (Alt, Common_Type);
2086 Alt := First (Alternatives (N));
2087 while Present (Alt) loop
2089 if not Is_Overloaded (Alt) then
2090 Common_Type := Etype (Alt);
2093 Get_First_Interp (Alt, Index, It);
2094 while Present (It.Typ) loop
2096 Has_Compatible_Type (Candidate_Interps, It.Typ)
2098 Remove_Interp (Index);
2101 Get_Next_Interp (Index, It);
2104 Get_First_Interp (Alt, Index, It);
2107 Error_Msg_N ("alternative has no legal type", Alt);
2111 -- If alternative is not overloaded, we have a unique type
2114 Set_Etype (Alt, It.Typ);
2115 Get_Next_Interp (Index, It);
2118 Set_Is_Overloaded (Alt, False);
2119 Common_Type := Etype (Alt);
2122 Candidate_Interps := Alt;
2129 Set_Etype (N, Standard_Boolean);
2131 if Present (Common_Type) then
2132 Set_Etype (L, Common_Type);
2133 Set_Is_Overloaded (L, False);
2136 Error_Msg_N ("cannot resolve membership operation", N);
2138 end Analyze_Set_Membership;
2140 -- Start of processing for Analyze_Membership_Op
2143 Analyze_Expression (L);
2146 and then Extensions_Allowed
2148 Analyze_Set_Membership;
2152 if Nkind (R) = N_Range
2153 or else (Nkind (R) = N_Attribute_Reference
2154 and then Attribute_Name (R) = Name_Range)
2158 if not Is_Overloaded (L) then
2159 Try_One_Interp (Etype (L));
2162 Get_First_Interp (L, Index, It);
2163 while Present (It.Typ) loop
2164 Try_One_Interp (It.Typ);
2165 Get_Next_Interp (Index, It);
2169 -- If not a range, it can only be a subtype mark, or else there
2170 -- is a more basic error, to be diagnosed in Find_Type.
2175 if Is_Entity_Name (R) then
2176 Check_Fully_Declared (Entity (R), R);
2180 -- Compatibility between expression and subtype mark or range is
2181 -- checked during resolution. The result of the operation is Boolean
2184 Set_Etype (N, Standard_Boolean);
2186 if Comes_From_Source (N)
2187 and then Present (Right_Opnd (N))
2188 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2190 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2192 end Analyze_Membership_Op;
2194 ----------------------
2195 -- Analyze_Negation --
2196 ----------------------
2198 procedure Analyze_Negation (N : Node_Id) is
2199 R : constant Node_Id := Right_Opnd (N);
2200 Op_Id : Entity_Id := Entity (N);
2203 Set_Etype (N, Any_Type);
2204 Candidate_Type := Empty;
2206 Analyze_Expression (R);
2208 if Present (Op_Id) then
2209 if Ekind (Op_Id) = E_Operator then
2210 Find_Negation_Types (R, Op_Id, N);
2212 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2216 Op_Id := Get_Name_Entity_Id (Chars (N));
2217 while Present (Op_Id) loop
2218 if Ekind (Op_Id) = E_Operator then
2219 Find_Negation_Types (R, Op_Id, N);
2221 Analyze_User_Defined_Unary_Op (N, Op_Id);
2224 Op_Id := Homonym (Op_Id);
2229 end Analyze_Negation;
2235 procedure Analyze_Null (N : Node_Id) is
2237 Set_Etype (N, Any_Access);
2240 ----------------------
2241 -- Analyze_One_Call --
2242 ----------------------
2244 procedure Analyze_One_Call
2248 Success : out Boolean;
2249 Skip_First : Boolean := False)
2251 Actuals : constant List_Id := Parameter_Associations (N);
2252 Prev_T : constant Entity_Id := Etype (N);
2254 Must_Skip : constant Boolean := Skip_First
2255 or else Nkind (Original_Node (N)) = N_Selected_Component
2257 (Nkind (Original_Node (N)) = N_Indexed_Component
2258 and then Nkind (Prefix (Original_Node (N)))
2259 = N_Selected_Component);
2260 -- The first formal must be omitted from the match when trying to find
2261 -- a primitive operation that is a possible interpretation, and also
2262 -- after the call has been rewritten, because the corresponding actual
2263 -- is already known to be compatible, and because this may be an
2264 -- indexing of a call with default parameters.
2268 Is_Indexed : Boolean := False;
2269 Is_Indirect : Boolean := False;
2270 Subp_Type : constant Entity_Id := Etype (Nam);
2273 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2274 -- There may be a user-defined operator that hides the current
2275 -- interpretation. We must check for this independently of the
2276 -- analysis of the call with the user-defined operation, because
2277 -- the parameter names may be wrong and yet the hiding takes place.
2278 -- This fixes a problem with ACATS test B34014O.
2280 -- When the type Address is a visible integer type, and the DEC
2281 -- system extension is visible, the predefined operator may be
2282 -- hidden as well, by one of the address operations in auxdec.
2283 -- Finally, The abstract operations on address do not hide the
2284 -- predefined operator (this is the purpose of making them abstract).
2286 procedure Indicate_Name_And_Type;
2287 -- If candidate interpretation matches, indicate name and type of
2288 -- result on call node.
2290 ----------------------------
2291 -- Indicate_Name_And_Type --
2292 ----------------------------
2294 procedure Indicate_Name_And_Type is
2296 Add_One_Interp (N, Nam, Etype (Nam));
2299 -- If the prefix of the call is a name, indicate the entity
2300 -- being called. If it is not a name, it is an expression that
2301 -- denotes an access to subprogram or else an entry or family. In
2302 -- the latter case, the name is a selected component, and the entity
2303 -- being called is noted on the selector.
2305 if not Is_Type (Nam) then
2306 if Is_Entity_Name (Name (N))
2307 or else Nkind (Name (N)) = N_Operator_Symbol
2309 Set_Entity (Name (N), Nam);
2311 elsif Nkind (Name (N)) = N_Selected_Component then
2312 Set_Entity (Selector_Name (Name (N)), Nam);
2316 if Debug_Flag_E and not Report then
2317 Write_Str (" Overloaded call ");
2318 Write_Int (Int (N));
2319 Write_Str (" compatible with ");
2320 Write_Int (Int (Nam));
2323 end Indicate_Name_And_Type;
2325 ------------------------
2326 -- Operator_Hidden_By --
2327 ------------------------
2329 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2330 Act1 : constant Node_Id := First_Actual (N);
2331 Act2 : constant Node_Id := Next_Actual (Act1);
2332 Form1 : constant Entity_Id := First_Formal (Fun);
2333 Form2 : constant Entity_Id := Next_Formal (Form1);
2336 if Ekind (Fun) /= E_Function
2337 or else Is_Abstract_Subprogram (Fun)
2341 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2344 elsif Present (Form2) then
2346 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2351 elsif Present (Act2) then
2355 -- Now we know that the arity of the operator matches the function,
2356 -- and the function call is a valid interpretation. The function
2357 -- hides the operator if it has the right signature, or if one of
2358 -- its operands is a non-abstract operation on Address when this is
2359 -- a visible integer type.
2361 return Hides_Op (Fun, Nam)
2362 or else Is_Descendent_Of_Address (Etype (Form1))
2365 and then Is_Descendent_Of_Address (Etype (Form2)));
2366 end Operator_Hidden_By;
2368 -- Start of processing for Analyze_One_Call
2373 -- If the subprogram has no formals or if all the formals have defaults,
2374 -- and the return type is an array type, the node may denote an indexing
2375 -- of the result of a parameterless call. In Ada 2005, the subprogram
2376 -- may have one non-defaulted formal, and the call may have been written
2377 -- in prefix notation, so that the rebuilt parameter list has more than
2380 if not Is_Overloadable (Nam)
2381 and then Ekind (Nam) /= E_Subprogram_Type
2382 and then Ekind (Nam) /= E_Entry_Family
2387 -- An indexing requires at least one actual
2389 if not Is_Empty_List (Actuals)
2391 (Needs_No_Actuals (Nam)
2393 (Needs_One_Actual (Nam)
2394 and then Present (Next_Actual (First (Actuals)))))
2396 if Is_Array_Type (Subp_Type) then
2397 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2399 elsif Is_Access_Type (Subp_Type)
2400 and then Is_Array_Type (Designated_Type (Subp_Type))
2404 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2406 -- The prefix can also be a parameterless function that returns an
2407 -- access to subprogram, in which case this is an indirect call.
2408 -- If this succeeds, an explicit dereference is added later on,
2409 -- in Analyze_Call or Resolve_Call.
2411 elsif Is_Access_Type (Subp_Type)
2412 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2414 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2419 -- If the call has been transformed into a slice, it is of the form
2420 -- F (Subtype) where F is parameterless. The node has been rewritten in
2421 -- Try_Indexed_Call and there is nothing else to do.
2424 and then Nkind (N) = N_Slice
2430 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2434 -- If an indirect call is a possible interpretation, indicate
2435 -- success to the caller.
2441 -- Mismatch in number or names of parameters
2443 elsif Debug_Flag_E then
2444 Write_Str (" normalization fails in call ");
2445 Write_Int (Int (N));
2446 Write_Str (" with subprogram ");
2447 Write_Int (Int (Nam));
2451 -- If the context expects a function call, discard any interpretation
2452 -- that is a procedure. If the node is not overloaded, leave as is for
2453 -- better error reporting when type mismatch is found.
2455 elsif Nkind (N) = N_Function_Call
2456 and then Is_Overloaded (Name (N))
2457 and then Ekind (Nam) = E_Procedure
2461 -- Ditto for function calls in a procedure context
2463 elsif Nkind (N) = N_Procedure_Call_Statement
2464 and then Is_Overloaded (Name (N))
2465 and then Etype (Nam) /= Standard_Void_Type
2469 elsif No (Actuals) then
2471 -- If Normalize succeeds, then there are default parameters for
2474 Indicate_Name_And_Type;
2476 elsif Ekind (Nam) = E_Operator then
2477 if Nkind (N) = N_Procedure_Call_Statement then
2481 -- This can occur when the prefix of the call is an operator
2482 -- name or an expanded name whose selector is an operator name.
2484 Analyze_Operator_Call (N, Nam);
2486 if Etype (N) /= Prev_T then
2488 -- Check that operator is not hidden by a function interpretation
2490 if Is_Overloaded (Name (N)) then
2496 Get_First_Interp (Name (N), I, It);
2497 while Present (It.Nam) loop
2498 if Operator_Hidden_By (It.Nam) then
2499 Set_Etype (N, Prev_T);
2503 Get_Next_Interp (I, It);
2508 -- If operator matches formals, record its name on the call.
2509 -- If the operator is overloaded, Resolve will select the
2510 -- correct one from the list of interpretations. The call
2511 -- node itself carries the first candidate.
2513 Set_Entity (Name (N), Nam);
2516 elsif Report and then Etype (N) = Any_Type then
2517 Error_Msg_N ("incompatible arguments for operator", N);
2521 -- Normalize_Actuals has chained the named associations in the
2522 -- correct order of the formals.
2524 Actual := First_Actual (N);
2525 Formal := First_Formal (Nam);
2527 -- If we are analyzing a call rewritten from object notation,
2528 -- skip first actual, which may be rewritten later as an
2529 -- explicit dereference.
2532 Next_Actual (Actual);
2533 Next_Formal (Formal);
2536 while Present (Actual) and then Present (Formal) loop
2537 if Nkind (Parent (Actual)) /= N_Parameter_Association
2538 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2540 -- The actual can be compatible with the formal, but we must
2541 -- also check that the context is not an address type that is
2542 -- visibly an integer type, as is the case in VMS_64. In this
2543 -- case the use of literals is illegal, except in the body of
2544 -- descendents of system, where arithmetic operations on
2545 -- address are of course used.
2547 if Has_Compatible_Type (Actual, Etype (Formal))
2549 (Etype (Actual) /= Universal_Integer
2550 or else not Is_Descendent_Of_Address (Etype (Formal))
2552 Is_Predefined_File_Name
2553 (Unit_File_Name (Get_Source_Unit (N))))
2555 Next_Actual (Actual);
2556 Next_Formal (Formal);
2559 if Debug_Flag_E then
2560 Write_Str (" type checking fails in call ");
2561 Write_Int (Int (N));
2562 Write_Str (" with formal ");
2563 Write_Int (Int (Formal));
2564 Write_Str (" in subprogram ");
2565 Write_Int (Int (Nam));
2569 if Report and not Is_Indexed and not Is_Indirect then
2571 -- Ada 2005 (AI-251): Complete the error notification
2572 -- to help new Ada 2005 users.
2574 if Is_Class_Wide_Type (Etype (Formal))
2575 and then Is_Interface (Etype (Etype (Formal)))
2576 and then not Interface_Present_In_Ancestor
2577 (Typ => Etype (Actual),
2578 Iface => Etype (Etype (Formal)))
2581 ("(Ada 2005) does not implement interface }",
2582 Actual, Etype (Etype (Formal)));
2585 Wrong_Type (Actual, Etype (Formal));
2587 if Nkind (Actual) = N_Op_Eq
2588 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2590 Formal := First_Formal (Nam);
2591 while Present (Formal) loop
2592 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2593 Error_Msg_N -- CODEFIX
2594 ("possible misspelling of `='>`!", Actual);
2598 Next_Formal (Formal);
2602 if All_Errors_Mode then
2603 Error_Msg_Sloc := Sloc (Nam);
2605 if Is_Overloadable (Nam)
2606 and then Present (Alias (Nam))
2607 and then not Comes_From_Source (Nam)
2610 ("\\ =='> in call to inherited operation & #!",
2613 elsif Ekind (Nam) = E_Subprogram_Type then
2615 Access_To_Subprogram_Typ :
2616 constant Entity_Id :=
2618 (Associated_Node_For_Itype (Nam));
2621 "\\ =='> in call to dereference of &#!",
2622 Actual, Access_To_Subprogram_Typ);
2627 ("\\ =='> in call to &#!", Actual, Nam);
2637 -- Normalize_Actuals has verified that a default value exists
2638 -- for this formal. Current actual names a subsequent formal.
2640 Next_Formal (Formal);
2644 -- On exit, all actuals match
2646 Indicate_Name_And_Type;
2648 end Analyze_One_Call;
2650 ---------------------------
2651 -- Analyze_Operator_Call --
2652 ---------------------------
2654 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2655 Op_Name : constant Name_Id := Chars (Op_Id);
2656 Act1 : constant Node_Id := First_Actual (N);
2657 Act2 : constant Node_Id := Next_Actual (Act1);
2660 -- Binary operator case
2662 if Present (Act2) then
2664 -- If more than two operands, then not binary operator after all
2666 if Present (Next_Actual (Act2)) then
2669 elsif Op_Name = Name_Op_Add
2670 or else Op_Name = Name_Op_Subtract
2671 or else Op_Name = Name_Op_Multiply
2672 or else Op_Name = Name_Op_Divide
2673 or else Op_Name = Name_Op_Mod
2674 or else Op_Name = Name_Op_Rem
2675 or else Op_Name = Name_Op_Expon
2677 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2679 elsif Op_Name = Name_Op_And
2680 or else Op_Name = Name_Op_Or
2681 or else Op_Name = Name_Op_Xor
2683 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2685 elsif Op_Name = Name_Op_Lt
2686 or else Op_Name = Name_Op_Le
2687 or else Op_Name = Name_Op_Gt
2688 or else Op_Name = Name_Op_Ge
2690 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2692 elsif Op_Name = Name_Op_Eq
2693 or else Op_Name = Name_Op_Ne
2695 Find_Equality_Types (Act1, Act2, Op_Id, N);
2697 elsif Op_Name = Name_Op_Concat then
2698 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2700 -- Is this else null correct, or should it be an abort???
2706 -- Unary operator case
2709 if Op_Name = Name_Op_Subtract or else
2710 Op_Name = Name_Op_Add or else
2711 Op_Name = Name_Op_Abs
2713 Find_Unary_Types (Act1, Op_Id, N);
2716 Op_Name = Name_Op_Not
2718 Find_Negation_Types (Act1, Op_Id, N);
2720 -- Is this else null correct, or should it be an abort???
2726 end Analyze_Operator_Call;
2728 -------------------------------------------
2729 -- Analyze_Overloaded_Selected_Component --
2730 -------------------------------------------
2732 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
2733 Nam : constant Node_Id := Prefix (N);
2734 Sel : constant Node_Id := Selector_Name (N);
2741 Set_Etype (Sel, Any_Type);
2743 Get_First_Interp (Nam, I, It);
2744 while Present (It.Typ) loop
2745 if Is_Access_Type (It.Typ) then
2746 T := Designated_Type (It.Typ);
2747 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2752 if Is_Record_Type (T) then
2754 -- If the prefix is a class-wide type, the visible components are
2755 -- those of the base type.
2757 if Is_Class_Wide_Type (T) then
2761 Comp := First_Entity (T);
2762 while Present (Comp) loop
2763 if Chars (Comp) = Chars (Sel)
2764 and then Is_Visible_Component (Comp)
2767 -- AI05-105: if the context is an object renaming with
2768 -- an anonymous access type, the expected type of the
2769 -- object must be anonymous. This is a name resolution rule.
2771 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
2772 or else No (Access_Definition (Parent (N)))
2773 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
2775 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
2777 Set_Entity (Sel, Comp);
2778 Set_Etype (Sel, Etype (Comp));
2779 Add_One_Interp (N, Etype (Comp), Etype (Comp));
2781 -- This also specifies a candidate to resolve the name.
2782 -- Further overloading will be resolved from context.
2783 -- The selector name itself does not carry overloading
2786 Set_Etype (Nam, It.Typ);
2789 -- Named access type in the context of a renaming
2790 -- declaration with an access definition. Remove
2791 -- inapplicable candidate.
2800 elsif Is_Concurrent_Type (T) then
2801 Comp := First_Entity (T);
2802 while Present (Comp)
2803 and then Comp /= First_Private_Entity (T)
2805 if Chars (Comp) = Chars (Sel) then
2806 if Is_Overloadable (Comp) then
2807 Add_One_Interp (Sel, Comp, Etype (Comp));
2809 Set_Entity_With_Style_Check (Sel, Comp);
2810 Generate_Reference (Comp, Sel);
2813 Set_Etype (Sel, Etype (Comp));
2814 Set_Etype (N, Etype (Comp));
2815 Set_Etype (Nam, It.Typ);
2817 -- For access type case, introduce explicit deference for
2818 -- more uniform treatment of entry calls. Do this only
2819 -- once if several interpretations yield an access type.
2821 if Is_Access_Type (Etype (Nam))
2822 and then Nkind (Nam) /= N_Explicit_Dereference
2824 Insert_Explicit_Dereference (Nam);
2826 (Warn_On_Dereference, "?implicit dereference", N);
2833 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2836 Get_Next_Interp (I, It);
2839 if Etype (N) = Any_Type
2840 and then not Try_Object_Operation (N)
2842 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
2843 Set_Entity (Sel, Any_Id);
2844 Set_Etype (Sel, Any_Type);
2846 end Analyze_Overloaded_Selected_Component;
2848 ----------------------------------
2849 -- Analyze_Qualified_Expression --
2850 ----------------------------------
2852 procedure Analyze_Qualified_Expression (N : Node_Id) is
2853 Mark : constant Entity_Id := Subtype_Mark (N);
2854 Expr : constant Node_Id := Expression (N);
2860 Analyze_Expression (Expr);
2862 Set_Etype (N, Any_Type);
2867 if T = Any_Type then
2871 Check_Fully_Declared (T, N);
2873 -- If expected type is class-wide, check for exact match before
2874 -- expansion, because if the expression is a dispatching call it
2875 -- may be rewritten as explicit dereference with class-wide result.
2876 -- If expression is overloaded, retain only interpretations that
2877 -- will yield exact matches.
2879 if Is_Class_Wide_Type (T) then
2880 if not Is_Overloaded (Expr) then
2881 if Base_Type (Etype (Expr)) /= Base_Type (T) then
2882 if Nkind (Expr) = N_Aggregate then
2883 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
2885 Wrong_Type (Expr, T);
2890 Get_First_Interp (Expr, I, It);
2892 while Present (It.Nam) loop
2893 if Base_Type (It.Typ) /= Base_Type (T) then
2897 Get_Next_Interp (I, It);
2903 end Analyze_Qualified_Expression;
2909 procedure Analyze_Range (N : Node_Id) is
2910 L : constant Node_Id := Low_Bound (N);
2911 H : constant Node_Id := High_Bound (N);
2912 I1, I2 : Interp_Index;
2915 procedure Check_Common_Type (T1, T2 : Entity_Id);
2916 -- Verify the compatibility of two types, and choose the
2917 -- non universal one if the other is universal.
2919 procedure Check_High_Bound (T : Entity_Id);
2920 -- Test one interpretation of the low bound against all those
2921 -- of the high bound.
2923 procedure Check_Universal_Expression (N : Node_Id);
2924 -- In Ada83, reject bounds of a universal range that are not
2925 -- literals or entity names.
2927 -----------------------
2928 -- Check_Common_Type --
2929 -----------------------
2931 procedure Check_Common_Type (T1, T2 : Entity_Id) is
2933 if Covers (T1 => T1, T2 => T2)
2935 Covers (T1 => T2, T2 => T1)
2937 if T1 = Universal_Integer
2938 or else T1 = Universal_Real
2939 or else T1 = Any_Character
2941 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
2944 Add_One_Interp (N, T1, T1);
2947 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
2950 end Check_Common_Type;
2952 ----------------------
2953 -- Check_High_Bound --
2954 ----------------------
2956 procedure Check_High_Bound (T : Entity_Id) is
2958 if not Is_Overloaded (H) then
2959 Check_Common_Type (T, Etype (H));
2961 Get_First_Interp (H, I2, It2);
2962 while Present (It2.Typ) loop
2963 Check_Common_Type (T, It2.Typ);
2964 Get_Next_Interp (I2, It2);
2967 end Check_High_Bound;
2969 -----------------------------
2970 -- Is_Universal_Expression --
2971 -----------------------------
2973 procedure Check_Universal_Expression (N : Node_Id) is
2975 if Etype (N) = Universal_Integer
2976 and then Nkind (N) /= N_Integer_Literal
2977 and then not Is_Entity_Name (N)
2978 and then Nkind (N) /= N_Attribute_Reference
2980 Error_Msg_N ("illegal bound in discrete range", N);
2982 end Check_Universal_Expression;
2984 -- Start of processing for Analyze_Range
2987 Set_Etype (N, Any_Type);
2988 Analyze_Expression (L);
2989 Analyze_Expression (H);
2991 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
2995 if not Is_Overloaded (L) then
2996 Check_High_Bound (Etype (L));
2998 Get_First_Interp (L, I1, It1);
2999 while Present (It1.Typ) loop
3000 Check_High_Bound (It1.Typ);
3001 Get_Next_Interp (I1, It1);
3005 -- If result is Any_Type, then we did not find a compatible pair
3007 if Etype (N) = Any_Type then
3008 Error_Msg_N ("incompatible types in range ", N);
3012 if Ada_Version = Ada_83
3014 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
3015 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
3017 Check_Universal_Expression (L);
3018 Check_Universal_Expression (H);
3022 -----------------------
3023 -- Analyze_Reference --
3024 -----------------------
3026 procedure Analyze_Reference (N : Node_Id) is
3027 P : constant Node_Id := Prefix (N);
3030 Acc_Type : Entity_Id;
3035 -- An interesting error check, if we take the 'Reference of an object
3036 -- for which a pragma Atomic or Volatile has been given, and the type
3037 -- of the object is not Atomic or Volatile, then we are in trouble. The
3038 -- problem is that no trace of the atomic/volatile status will remain
3039 -- for the backend to respect when it deals with the resulting pointer,
3040 -- since the pointer type will not be marked atomic (it is a pointer to
3041 -- the base type of the object).
3043 -- It is not clear if that can ever occur, but in case it does, we will
3044 -- generate an error message. Not clear if this message can ever be
3045 -- generated, and pretty clear that it represents a bug if it is, still
3046 -- seems worth checking!
3050 if Is_Entity_Name (P)
3051 and then Is_Object_Reference (P)
3056 if (Has_Atomic_Components (E)
3057 and then not Has_Atomic_Components (T))
3059 (Has_Volatile_Components (E)
3060 and then not Has_Volatile_Components (T))
3061 or else (Is_Atomic (E) and then not Is_Atomic (T))
3062 or else (Is_Volatile (E) and then not Is_Volatile (T))
3064 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
3068 -- Carry on with normal processing
3070 Acc_Type := Create_Itype (E_Allocator_Type, N);
3071 Set_Etype (Acc_Type, Acc_Type);
3072 Set_Directly_Designated_Type (Acc_Type, Etype (P));
3073 Set_Etype (N, Acc_Type);
3074 end Analyze_Reference;
3076 --------------------------------
3077 -- Analyze_Selected_Component --
3078 --------------------------------
3080 -- Prefix is a record type or a task or protected type. In the
3081 -- later case, the selector must denote a visible entry.
3083 procedure Analyze_Selected_Component (N : Node_Id) is
3084 Name : constant Node_Id := Prefix (N);
3085 Sel : constant Node_Id := Selector_Name (N);
3088 Has_Candidate : Boolean := False;
3091 Pent : Entity_Id := Empty;
3092 Prefix_Type : Entity_Id;
3094 Type_To_Use : Entity_Id;
3095 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
3096 -- a class-wide type, we use its root type, whose components are
3097 -- present in the class-wide type.
3099 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
3100 -- It is known that the parent of N denotes a subprogram call. Comp
3101 -- is an overloadable component of the concurrent type of the prefix.
3102 -- Determine whether all formals of the parent of N and Comp are mode
3103 -- conformant. If the parent node is not analyzed yet it may be an
3104 -- indexed component rather than a function call.
3106 ------------------------------
3107 -- Has_Mode_Conformant_Spec --
3108 ------------------------------
3110 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
3111 Comp_Param : Entity_Id;
3113 Param_Typ : Entity_Id;
3116 Comp_Param := First_Formal (Comp);
3118 if Nkind (Parent (N)) = N_Indexed_Component then
3119 Param := First (Expressions (Parent (N)));
3121 Param := First (Parameter_Associations (Parent (N)));
3124 while Present (Comp_Param)
3125 and then Present (Param)
3127 Param_Typ := Find_Parameter_Type (Param);
3129 if Present (Param_Typ)
3131 not Conforming_Types
3132 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3137 Next_Formal (Comp_Param);
3141 -- One of the specs has additional formals
3143 if Present (Comp_Param) or else Present (Param) then
3148 end Has_Mode_Conformant_Spec;
3150 -- Start of processing for Analyze_Selected_Component
3153 Set_Etype (N, Any_Type);
3155 if Is_Overloaded (Name) then
3156 Analyze_Overloaded_Selected_Component (N);
3159 elsif Etype (Name) = Any_Type then
3160 Set_Entity (Sel, Any_Id);
3161 Set_Etype (Sel, Any_Type);
3165 Prefix_Type := Etype (Name);
3168 if Is_Access_Type (Prefix_Type) then
3170 -- A RACW object can never be used as prefix of a selected
3171 -- component since that means it is dereferenced without
3172 -- being a controlling operand of a dispatching operation
3173 -- (RM E.2.2(16/1)). Before reporting an error, we must check
3174 -- whether this is actually a dispatching call in prefix form.
3176 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3177 and then Comes_From_Source (N)
3179 if Try_Object_Operation (N) then
3183 ("invalid dereference of a remote access-to-class-wide value",
3187 -- Normal case of selected component applied to access type
3190 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3192 if Is_Entity_Name (Name) then
3193 Pent := Entity (Name);
3194 elsif Nkind (Name) = N_Selected_Component
3195 and then Is_Entity_Name (Selector_Name (Name))
3197 Pent := Entity (Selector_Name (Name));
3200 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3203 -- If we have an explicit dereference of a remote access-to-class-wide
3204 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3205 -- have to check for the case of a prefix that is a controlling operand
3206 -- of a prefixed dispatching call, as the dereference is legal in that
3207 -- case. Normally this condition is checked in Validate_Remote_Access_
3208 -- To_Class_Wide_Type, but we have to defer the checking for selected
3209 -- component prefixes because of the prefixed dispatching call case.
3210 -- Note that implicit dereferences are checked for this just above.
3212 elsif Nkind (Name) = N_Explicit_Dereference
3213 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3214 and then Comes_From_Source (N)
3216 if Try_Object_Operation (N) then
3220 ("invalid dereference of a remote access-to-class-wide value",
3225 -- (Ada 2005): if the prefix is the limited view of a type, and
3226 -- the context already includes the full view, use the full view
3227 -- in what follows, either to retrieve a component of to find
3228 -- a primitive operation. If the prefix is an explicit dereference,
3229 -- set the type of the prefix to reflect this transformation.
3230 -- If the non-limited view is itself an incomplete type, get the
3231 -- full view if available.
3233 if Is_Incomplete_Type (Prefix_Type)
3234 and then From_With_Type (Prefix_Type)
3235 and then Present (Non_Limited_View (Prefix_Type))
3237 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3239 if Nkind (N) = N_Explicit_Dereference then
3240 Set_Etype (Prefix (N), Prefix_Type);
3243 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3244 and then From_With_Type (Prefix_Type)
3245 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3248 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3250 if Nkind (N) = N_Explicit_Dereference then
3251 Set_Etype (Prefix (N), Prefix_Type);
3255 if Ekind (Prefix_Type) = E_Private_Subtype then
3256 Prefix_Type := Base_Type (Prefix_Type);
3259 Type_To_Use := Prefix_Type;
3261 -- For class-wide types, use the entity list of the root type. This
3262 -- indirection is specially important for private extensions because
3263 -- only the root type get switched (not the class-wide type).
3265 if Is_Class_Wide_Type (Prefix_Type) then
3266 Type_To_Use := Root_Type (Prefix_Type);
3269 Comp := First_Entity (Type_To_Use);
3271 -- If the selector has an original discriminant, the node appears in
3272 -- an instance. Replace the discriminant with the corresponding one
3273 -- in the current discriminated type. For nested generics, this must
3274 -- be done transitively, so note the new original discriminant.
3276 if Nkind (Sel) = N_Identifier
3277 and then Present (Original_Discriminant (Sel))
3279 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3281 -- Mark entity before rewriting, for completeness and because
3282 -- subsequent semantic checks might examine the original node.
3284 Set_Entity (Sel, Comp);
3285 Rewrite (Selector_Name (N),
3286 New_Occurrence_Of (Comp, Sloc (N)));
3287 Set_Original_Discriminant (Selector_Name (N), Comp);
3288 Set_Etype (N, Etype (Comp));
3290 if Is_Access_Type (Etype (Name)) then
3291 Insert_Explicit_Dereference (Name);
3292 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3295 elsif Is_Record_Type (Prefix_Type) then
3297 -- Find component with given name
3299 while Present (Comp) loop
3300 if Chars (Comp) = Chars (Sel)
3301 and then Is_Visible_Component (Comp)
3303 Set_Entity_With_Style_Check (Sel, Comp);
3304 Set_Etype (Sel, Etype (Comp));
3306 if Ekind (Comp) = E_Discriminant then
3307 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3309 ("cannot reference discriminant of Unchecked_Union",
3313 if Is_Generic_Type (Prefix_Type)
3315 Is_Generic_Type (Root_Type (Prefix_Type))
3317 Set_Original_Discriminant (Sel, Comp);
3321 -- Resolve the prefix early otherwise it is not possible to
3322 -- build the actual subtype of the component: it may need
3323 -- to duplicate this prefix and duplication is only allowed
3324 -- on fully resolved expressions.
3328 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3329 -- subtypes in a package specification.
3332 -- limited with Pkg;
3334 -- type Acc_Inc is access Pkg.T;
3336 -- N : Natural := X.all.Comp; -- ERROR, limited view
3337 -- end Pkg; -- Comp is not visible
3339 if Nkind (Name) = N_Explicit_Dereference
3340 and then From_With_Type (Etype (Prefix (Name)))
3341 and then not Is_Potentially_Use_Visible (Etype (Name))
3342 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3343 N_Package_Specification
3346 ("premature usage of incomplete}", Prefix (Name),
3347 Etype (Prefix (Name)));
3350 -- We never need an actual subtype for the case of a selection
3351 -- for a indexed component of a non-packed array, since in
3352 -- this case gigi generates all the checks and can find the
3353 -- necessary bounds information.
3355 -- We also do not need an actual subtype for the case of
3356 -- a first, last, length, or range attribute applied to a
3357 -- non-packed array, since gigi can again get the bounds in
3358 -- these cases (gigi cannot handle the packed case, since it
3359 -- has the bounds of the packed array type, not the original
3360 -- bounds of the type). However, if the prefix is itself a
3361 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3362 -- as a dynamic-sized temporary, so we do generate an actual
3363 -- subtype for this case.
3365 Parent_N := Parent (N);
3367 if not Is_Packed (Etype (Comp))
3369 ((Nkind (Parent_N) = N_Indexed_Component
3370 and then Nkind (Name) /= N_Selected_Component)
3372 (Nkind (Parent_N) = N_Attribute_Reference
3373 and then (Attribute_Name (Parent_N) = Name_First
3375 Attribute_Name (Parent_N) = Name_Last
3377 Attribute_Name (Parent_N) = Name_Length
3379 Attribute_Name (Parent_N) = Name_Range)))
3381 Set_Etype (N, Etype (Comp));
3383 -- If full analysis is not enabled, we do not generate an
3384 -- actual subtype, because in the absence of expansion
3385 -- reference to a formal of a protected type, for example,
3386 -- will not be properly transformed, and will lead to
3387 -- out-of-scope references in gigi.
3389 -- In all other cases, we currently build an actual subtype.
3390 -- It seems likely that many of these cases can be avoided,
3391 -- but right now, the front end makes direct references to the
3392 -- bounds (e.g. in generating a length check), and if we do
3393 -- not make an actual subtype, we end up getting a direct
3394 -- reference to a discriminant, which will not do.
3396 elsif Full_Analysis then
3398 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3399 Insert_Action (N, Act_Decl);
3401 if No (Act_Decl) then
3402 Set_Etype (N, Etype (Comp));
3405 -- Component type depends on discriminants. Enter the
3406 -- main attributes of the subtype.
3409 Subt : constant Entity_Id :=
3410 Defining_Identifier (Act_Decl);
3413 Set_Etype (Subt, Base_Type (Etype (Comp)));
3414 Set_Ekind (Subt, Ekind (Etype (Comp)));
3415 Set_Etype (N, Subt);
3419 -- If Full_Analysis not enabled, just set the Etype
3422 Set_Etype (N, Etype (Comp));
3428 -- If the prefix is a private extension, check only the visible
3429 -- components of the partial view. This must include the tag,
3430 -- which can appear in expanded code in a tag check.
3432 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3433 and then Chars (Selector_Name (N)) /= Name_uTag
3435 exit when Comp = Last_Entity (Type_To_Use);
3441 -- Ada 2005 (AI-252): The selected component can be interpreted as
3442 -- a prefixed view of a subprogram. Depending on the context, this is
3443 -- either a name that can appear in a renaming declaration, or part
3444 -- of an enclosing call given in prefix form.
3446 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3447 -- selected component should resolve to a name.
3449 if Ada_Version >= Ada_05
3450 and then Is_Tagged_Type (Prefix_Type)
3451 and then not Is_Concurrent_Type (Prefix_Type)
3453 if Nkind (Parent (N)) = N_Generic_Association
3454 or else Nkind (Parent (N)) = N_Requeue_Statement
3455 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3457 if Find_Primitive_Operation (N) then
3461 elsif Try_Object_Operation (N) then
3465 -- If the transformation fails, it will be necessary to redo the
3466 -- analysis with all errors enabled, to indicate candidate
3467 -- interpretations and reasons for each failure ???
3471 elsif Is_Private_Type (Prefix_Type) then
3473 -- Allow access only to discriminants of the type. If the type has
3474 -- no full view, gigi uses the parent type for the components, so we
3475 -- do the same here.
3477 if No (Full_View (Prefix_Type)) then
3478 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3479 Comp := First_Entity (Type_To_Use);
3482 while Present (Comp) loop
3483 if Chars (Comp) = Chars (Sel) then
3484 if Ekind (Comp) = E_Discriminant then
3485 Set_Entity_With_Style_Check (Sel, Comp);
3486 Generate_Reference (Comp, Sel);
3488 Set_Etype (Sel, Etype (Comp));
3489 Set_Etype (N, Etype (Comp));
3491 if Is_Generic_Type (Prefix_Type)
3492 or else Is_Generic_Type (Root_Type (Prefix_Type))
3494 Set_Original_Discriminant (Sel, Comp);
3497 -- Before declaring an error, check whether this is tagged
3498 -- private type and a call to a primitive operation.
3500 elsif Ada_Version >= Ada_05
3501 and then Is_Tagged_Type (Prefix_Type)
3502 and then Try_Object_Operation (N)
3508 ("invisible selector for }",
3509 N, First_Subtype (Prefix_Type));
3510 Set_Entity (Sel, Any_Id);
3511 Set_Etype (N, Any_Type);
3520 elsif Is_Concurrent_Type (Prefix_Type) then
3522 -- Find visible operation with given name. For a protected type,
3523 -- the possible candidates are discriminants, entries or protected
3524 -- procedures. For a task type, the set can only include entries or
3525 -- discriminants if the task type is not an enclosing scope. If it
3526 -- is an enclosing scope (e.g. in an inner task) then all entities
3527 -- are visible, but the prefix must denote the enclosing scope, i.e.
3528 -- can only be a direct name or an expanded name.
3530 Set_Etype (Sel, Any_Type);
3531 In_Scope := In_Open_Scopes (Prefix_Type);
3533 while Present (Comp) loop
3534 if Chars (Comp) = Chars (Sel) then
3535 if Is_Overloadable (Comp) then
3536 Add_One_Interp (Sel, Comp, Etype (Comp));
3538 -- If the prefix is tagged, the correct interpretation may
3539 -- lie in the primitive or class-wide operations of the
3540 -- type. Perform a simple conformance check to determine
3541 -- whether Try_Object_Operation should be invoked even if
3542 -- a visible entity is found.
3544 if Is_Tagged_Type (Prefix_Type)
3546 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3548 N_Indexed_Component)
3549 and then Has_Mode_Conformant_Spec (Comp)
3551 Has_Candidate := True;
3554 elsif Ekind (Comp) = E_Discriminant
3555 or else Ekind (Comp) = E_Entry_Family
3557 and then Is_Entity_Name (Name))
3559 Set_Entity_With_Style_Check (Sel, Comp);
3560 Generate_Reference (Comp, Sel);
3566 Set_Etype (Sel, Etype (Comp));
3567 Set_Etype (N, Etype (Comp));
3569 if Ekind (Comp) = E_Discriminant then
3570 Set_Original_Discriminant (Sel, Comp);
3573 -- For access type case, introduce explicit deference for more
3574 -- uniform treatment of entry calls.
3576 if Is_Access_Type (Etype (Name)) then
3577 Insert_Explicit_Dereference (Name);
3579 (Warn_On_Dereference, "?implicit dereference", N);
3585 exit when not In_Scope
3587 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3590 -- If there is no visible entity with the given name or none of the
3591 -- visible entities are plausible interpretations, check whether
3592 -- there is some other primitive operation with that name.
3594 if Ada_Version >= Ada_05
3595 and then Is_Tagged_Type (Prefix_Type)
3597 if (Etype (N) = Any_Type
3598 or else not Has_Candidate)
3599 and then Try_Object_Operation (N)
3603 -- If the context is not syntactically a procedure call, it
3604 -- may be a call to a primitive function declared outside of
3605 -- the synchronized type.
3607 -- If the context is a procedure call, there might still be
3608 -- an overloading between an entry and a primitive procedure
3609 -- declared outside of the synchronized type, called in prefix
3610 -- notation. This is harder to disambiguate because in one case
3611 -- the controlling formal is implicit ???
3613 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
3614 and then Nkind (Parent (N)) /= N_Indexed_Component
3615 and then Try_Object_Operation (N)
3621 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3626 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
3629 -- If N still has no type, the component is not defined in the prefix
3631 if Etype (N) = Any_Type then
3633 -- If the prefix is a single concurrent object, use its name in the
3634 -- error message, rather than that of its anonymous type.
3636 if Is_Concurrent_Type (Prefix_Type)
3637 and then Is_Internal_Name (Chars (Prefix_Type))
3638 and then not Is_Derived_Type (Prefix_Type)
3639 and then Is_Entity_Name (Name)
3642 Error_Msg_Node_2 := Entity (Name);
3643 Error_Msg_NE ("no selector& for&", N, Sel);
3645 Check_Misspelled_Selector (Type_To_Use, Sel);
3647 elsif Is_Generic_Type (Prefix_Type)
3648 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
3649 and then Prefix_Type /= Etype (Prefix_Type)
3650 and then Is_Record_Type (Etype (Prefix_Type))
3652 -- If this is a derived formal type, the parent may have
3653 -- different visibility at this point. Try for an inherited
3654 -- component before reporting an error.
3656 Set_Etype (Prefix (N), Etype (Prefix_Type));
3657 Analyze_Selected_Component (N);
3660 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
3661 and then Is_Generic_Actual_Type (Prefix_Type)
3662 and then Present (Full_View (Prefix_Type))
3664 -- Similarly, if this the actual for a formal derived type, the
3665 -- component inherited from the generic parent may not be visible
3666 -- in the actual, but the selected component is legal.
3673 First_Component (Generic_Parent_Type (Parent (Prefix_Type)));
3674 while Present (Comp) loop
3675 if Chars (Comp) = Chars (Sel) then
3676 Set_Entity_With_Style_Check (Sel, Comp);
3677 Set_Etype (Sel, Etype (Comp));
3678 Set_Etype (N, Etype (Comp));
3682 Next_Component (Comp);
3685 pragma Assert (Etype (N) /= Any_Type);
3689 if Ekind (Prefix_Type) = E_Record_Subtype then
3691 -- Check whether this is a component of the base type
3692 -- which is absent from a statically constrained subtype.
3693 -- This will raise constraint error at run-time, but is
3694 -- not a compile-time error. When the selector is illegal
3695 -- for base type as well fall through and generate a
3696 -- compilation error anyway.
3698 Comp := First_Component (Base_Type (Prefix_Type));
3699 while Present (Comp) loop
3700 if Chars (Comp) = Chars (Sel)
3701 and then Is_Visible_Component (Comp)
3703 Set_Entity_With_Style_Check (Sel, Comp);
3704 Generate_Reference (Comp, Sel);
3705 Set_Etype (Sel, Etype (Comp));
3706 Set_Etype (N, Etype (Comp));
3708 -- Emit appropriate message. Gigi will replace the
3709 -- node subsequently with the appropriate Raise.
3711 Apply_Compile_Time_Constraint_Error
3712 (N, "component not present in }?",
3713 CE_Discriminant_Check_Failed,
3714 Ent => Prefix_Type, Rep => False);
3715 Set_Raises_Constraint_Error (N);
3719 Next_Component (Comp);
3724 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3725 Error_Msg_NE ("no selector& for}", N, Sel);
3727 Check_Misspelled_Selector (Type_To_Use, Sel);
3730 Set_Entity (Sel, Any_Id);
3731 Set_Etype (Sel, Any_Type);
3733 end Analyze_Selected_Component;
3735 ---------------------------
3736 -- Analyze_Short_Circuit --
3737 ---------------------------
3739 procedure Analyze_Short_Circuit (N : Node_Id) is
3740 L : constant Node_Id := Left_Opnd (N);
3741 R : constant Node_Id := Right_Opnd (N);
3746 Analyze_Expression (L);
3747 Analyze_Expression (R);
3748 Set_Etype (N, Any_Type);
3750 if not Is_Overloaded (L) then
3751 if Root_Type (Etype (L)) = Standard_Boolean
3752 and then Has_Compatible_Type (R, Etype (L))
3754 Add_One_Interp (N, Etype (L), Etype (L));
3758 Get_First_Interp (L, Ind, It);
3759 while Present (It.Typ) loop
3760 if Root_Type (It.Typ) = Standard_Boolean
3761 and then Has_Compatible_Type (R, It.Typ)
3763 Add_One_Interp (N, It.Typ, It.Typ);
3766 Get_Next_Interp (Ind, It);
3770 -- Here we have failed to find an interpretation. Clearly we know that
3771 -- it is not the case that both operands can have an interpretation of
3772 -- Boolean, but this is by far the most likely intended interpretation.
3773 -- So we simply resolve both operands as Booleans, and at least one of
3774 -- these resolutions will generate an error message, and we do not need
3775 -- to give another error message on the short circuit operation itself.
3777 if Etype (N) = Any_Type then
3778 Resolve (L, Standard_Boolean);
3779 Resolve (R, Standard_Boolean);
3780 Set_Etype (N, Standard_Boolean);
3782 end Analyze_Short_Circuit;
3788 procedure Analyze_Slice (N : Node_Id) is
3789 P : constant Node_Id := Prefix (N);
3790 D : constant Node_Id := Discrete_Range (N);
3791 Array_Type : Entity_Id;
3793 procedure Analyze_Overloaded_Slice;
3794 -- If the prefix is overloaded, select those interpretations that
3795 -- yield a one-dimensional array type.
3797 ------------------------------
3798 -- Analyze_Overloaded_Slice --
3799 ------------------------------
3801 procedure Analyze_Overloaded_Slice is
3807 Set_Etype (N, Any_Type);
3809 Get_First_Interp (P, I, It);
3810 while Present (It.Nam) loop
3813 if Is_Access_Type (Typ) then
3814 Typ := Designated_Type (Typ);
3815 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3818 if Is_Array_Type (Typ)
3819 and then Number_Dimensions (Typ) = 1
3820 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
3822 Add_One_Interp (N, Typ, Typ);
3825 Get_Next_Interp (I, It);
3828 if Etype (N) = Any_Type then
3829 Error_Msg_N ("expect array type in prefix of slice", N);
3831 end Analyze_Overloaded_Slice;
3833 -- Start of processing for Analyze_Slice
3839 if Is_Overloaded (P) then
3840 Analyze_Overloaded_Slice;
3843 Array_Type := Etype (P);
3844 Set_Etype (N, Any_Type);
3846 if Is_Access_Type (Array_Type) then
3847 Array_Type := Designated_Type (Array_Type);
3848 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3851 if not Is_Array_Type (Array_Type) then
3852 Wrong_Type (P, Any_Array);
3854 elsif Number_Dimensions (Array_Type) > 1 then
3856 ("type is not one-dimensional array in slice prefix", N);
3859 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
3861 Wrong_Type (D, Etype (First_Index (Array_Type)));
3864 Set_Etype (N, Array_Type);
3869 -----------------------------
3870 -- Analyze_Type_Conversion --
3871 -----------------------------
3873 procedure Analyze_Type_Conversion (N : Node_Id) is
3874 Expr : constant Node_Id := Expression (N);
3878 -- If Conversion_OK is set, then the Etype is already set, and the
3879 -- only processing required is to analyze the expression. This is
3880 -- used to construct certain "illegal" conversions which are not
3881 -- allowed by Ada semantics, but can be handled OK by Gigi, see
3882 -- Sinfo for further details.
3884 if Conversion_OK (N) then
3889 -- Otherwise full type analysis is required, as well as some semantic
3890 -- checks to make sure the argument of the conversion is appropriate.
3892 Find_Type (Subtype_Mark (N));
3893 T := Entity (Subtype_Mark (N));
3895 Check_Fully_Declared (T, N);
3896 Analyze_Expression (Expr);
3897 Validate_Remote_Type_Type_Conversion (N);
3899 -- Only remaining step is validity checks on the argument. These
3900 -- are skipped if the conversion does not come from the source.
3902 if not Comes_From_Source (N) then
3905 -- If there was an error in a generic unit, no need to replicate the
3906 -- error message. Conversely, constant-folding in the generic may
3907 -- transform the argument of a conversion into a string literal, which
3908 -- is legal. Therefore the following tests are not performed in an
3911 elsif In_Instance then
3914 elsif Nkind (Expr) = N_Null then
3915 Error_Msg_N ("argument of conversion cannot be null", N);
3916 Error_Msg_N ("\use qualified expression instead", N);
3917 Set_Etype (N, Any_Type);
3919 elsif Nkind (Expr) = N_Aggregate then
3920 Error_Msg_N ("argument of conversion cannot be aggregate", N);
3921 Error_Msg_N ("\use qualified expression instead", N);
3923 elsif Nkind (Expr) = N_Allocator then
3924 Error_Msg_N ("argument of conversion cannot be an allocator", N);
3925 Error_Msg_N ("\use qualified expression instead", N);
3927 elsif Nkind (Expr) = N_String_Literal then
3928 Error_Msg_N ("argument of conversion cannot be string literal", N);
3929 Error_Msg_N ("\use qualified expression instead", N);
3931 elsif Nkind (Expr) = N_Character_Literal then
3932 if Ada_Version = Ada_83 then
3935 Error_Msg_N ("argument of conversion cannot be character literal",
3937 Error_Msg_N ("\use qualified expression instead", N);
3940 elsif Nkind (Expr) = N_Attribute_Reference
3942 (Attribute_Name (Expr) = Name_Access or else
3943 Attribute_Name (Expr) = Name_Unchecked_Access or else
3944 Attribute_Name (Expr) = Name_Unrestricted_Access)
3946 Error_Msg_N ("argument of conversion cannot be access", N);
3947 Error_Msg_N ("\use qualified expression instead", N);
3949 end Analyze_Type_Conversion;
3951 ----------------------
3952 -- Analyze_Unary_Op --
3953 ----------------------
3955 procedure Analyze_Unary_Op (N : Node_Id) is
3956 R : constant Node_Id := Right_Opnd (N);
3957 Op_Id : Entity_Id := Entity (N);
3960 Set_Etype (N, Any_Type);
3961 Candidate_Type := Empty;
3963 Analyze_Expression (R);
3965 if Present (Op_Id) then
3966 if Ekind (Op_Id) = E_Operator then
3967 Find_Unary_Types (R, Op_Id, N);
3969 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3973 Op_Id := Get_Name_Entity_Id (Chars (N));
3974 while Present (Op_Id) loop
3975 if Ekind (Op_Id) = E_Operator then
3976 if No (Next_Entity (First_Entity (Op_Id))) then
3977 Find_Unary_Types (R, Op_Id, N);
3980 elsif Is_Overloadable (Op_Id) then
3981 Analyze_User_Defined_Unary_Op (N, Op_Id);
3984 Op_Id := Homonym (Op_Id);
3989 end Analyze_Unary_Op;
3991 ----------------------------------
3992 -- Analyze_Unchecked_Expression --
3993 ----------------------------------
3995 procedure Analyze_Unchecked_Expression (N : Node_Id) is
3997 Analyze (Expression (N), Suppress => All_Checks);
3998 Set_Etype (N, Etype (Expression (N)));
3999 Save_Interps (Expression (N), N);
4000 end Analyze_Unchecked_Expression;
4002 ---------------------------------------
4003 -- Analyze_Unchecked_Type_Conversion --
4004 ---------------------------------------
4006 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
4008 Find_Type (Subtype_Mark (N));
4009 Analyze_Expression (Expression (N));
4010 Set_Etype (N, Entity (Subtype_Mark (N)));
4011 end Analyze_Unchecked_Type_Conversion;
4013 ------------------------------------
4014 -- Analyze_User_Defined_Binary_Op --
4015 ------------------------------------
4017 procedure Analyze_User_Defined_Binary_Op
4022 -- Only do analysis if the operator Comes_From_Source, since otherwise
4023 -- the operator was generated by the expander, and all such operators
4024 -- always refer to the operators in package Standard.
4026 if Comes_From_Source (N) then
4028 F1 : constant Entity_Id := First_Formal (Op_Id);
4029 F2 : constant Entity_Id := Next_Formal (F1);
4032 -- Verify that Op_Id is a visible binary function. Note that since
4033 -- we know Op_Id is overloaded, potentially use visible means use
4034 -- visible for sure (RM 9.4(11)).
4036 if Ekind (Op_Id) = E_Function
4037 and then Present (F2)
4038 and then (Is_Immediately_Visible (Op_Id)
4039 or else Is_Potentially_Use_Visible (Op_Id))
4040 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
4041 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
4043 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4045 -- If the left operand is overloaded, indicate that the
4046 -- current type is a viable candidate. This is redundant
4047 -- in most cases, but for equality and comparison operators
4048 -- where the context does not impose a type on the operands,
4049 -- setting the proper type is necessary to avoid subsequent
4050 -- ambiguities during resolution, when both user-defined and
4051 -- predefined operators may be candidates.
4053 if Is_Overloaded (Left_Opnd (N)) then
4054 Set_Etype (Left_Opnd (N), Etype (F1));
4057 if Debug_Flag_E then
4058 Write_Str ("user defined operator ");
4059 Write_Name (Chars (Op_Id));
4060 Write_Str (" on node ");
4061 Write_Int (Int (N));
4067 end Analyze_User_Defined_Binary_Op;
4069 -----------------------------------
4070 -- Analyze_User_Defined_Unary_Op --
4071 -----------------------------------
4073 procedure Analyze_User_Defined_Unary_Op
4078 -- Only do analysis if the operator Comes_From_Source, since otherwise
4079 -- the operator was generated by the expander, and all such operators
4080 -- always refer to the operators in package Standard.
4082 if Comes_From_Source (N) then
4084 F : constant Entity_Id := First_Formal (Op_Id);
4087 -- Verify that Op_Id is a visible unary function. Note that since
4088 -- we know Op_Id is overloaded, potentially use visible means use
4089 -- visible for sure (RM 9.4(11)).
4091 if Ekind (Op_Id) = E_Function
4092 and then No (Next_Formal (F))
4093 and then (Is_Immediately_Visible (Op_Id)
4094 or else Is_Potentially_Use_Visible (Op_Id))
4095 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
4097 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4101 end Analyze_User_Defined_Unary_Op;
4103 ---------------------------
4104 -- Check_Arithmetic_Pair --
4105 ---------------------------
4107 procedure Check_Arithmetic_Pair
4108 (T1, T2 : Entity_Id;
4112 Op_Name : constant Name_Id := Chars (Op_Id);
4114 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
4115 -- Check whether the fixed-point type Typ has a user-defined operator
4116 -- (multiplication or division) that should hide the corresponding
4117 -- predefined operator. Used to implement Ada 2005 AI-264, to make
4118 -- such operators more visible and therefore useful.
4120 -- If the name of the operation is an expanded name with prefix
4121 -- Standard, the predefined universal fixed operator is available,
4122 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
4124 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
4125 -- Get specific type (i.e. non-universal type if there is one)
4131 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
4132 Bas : constant Entity_Id := Base_Type (Typ);
4138 -- If the universal_fixed operation is given explicitly the rule
4139 -- concerning primitive operations of the type do not apply.
4141 if Nkind (N) = N_Function_Call
4142 and then Nkind (Name (N)) = N_Expanded_Name
4143 and then Entity (Prefix (Name (N))) = Standard_Standard
4148 -- The operation is treated as primitive if it is declared in the
4149 -- same scope as the type, and therefore on the same entity chain.
4151 Ent := Next_Entity (Typ);
4152 while Present (Ent) loop
4153 if Chars (Ent) = Chars (Op) then
4154 F1 := First_Formal (Ent);
4155 F2 := Next_Formal (F1);
4157 -- The operation counts as primitive if either operand or
4158 -- result are of the given base type, and both operands are
4159 -- fixed point types.
4161 if (Base_Type (Etype (F1)) = Bas
4162 and then Is_Fixed_Point_Type (Etype (F2)))
4165 (Base_Type (Etype (F2)) = Bas
4166 and then Is_Fixed_Point_Type (Etype (F1)))
4169 (Base_Type (Etype (Ent)) = Bas
4170 and then Is_Fixed_Point_Type (Etype (F1))
4171 and then Is_Fixed_Point_Type (Etype (F2)))
4187 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4189 if T1 = Universal_Integer or else T1 = Universal_Real then
4190 return Base_Type (T2);
4192 return Base_Type (T1);
4196 -- Start of processing for Check_Arithmetic_Pair
4199 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4201 if Is_Numeric_Type (T1)
4202 and then Is_Numeric_Type (T2)
4203 and then (Covers (T1 => T1, T2 => T2)
4205 Covers (T1 => T2, T2 => T1))
4207 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4210 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4212 if Is_Fixed_Point_Type (T1)
4213 and then (Is_Fixed_Point_Type (T2)
4214 or else T2 = Universal_Real)
4216 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4217 -- and no further processing is required (this is the case of an
4218 -- operator constructed by Exp_Fixd for a fixed point operation)
4219 -- Otherwise add one interpretation with universal fixed result
4220 -- If the operator is given in functional notation, it comes
4221 -- from source and Fixed_As_Integer cannot apply.
4223 if (Nkind (N) not in N_Op
4224 or else not Treat_Fixed_As_Integer (N))
4226 (not Has_Fixed_Op (T1, Op_Id)
4227 or else Nkind (Parent (N)) = N_Type_Conversion)
4229 Add_One_Interp (N, Op_Id, Universal_Fixed);
4232 elsif Is_Fixed_Point_Type (T2)
4233 and then (Nkind (N) not in N_Op
4234 or else not Treat_Fixed_As_Integer (N))
4235 and then T1 = Universal_Real
4237 (not Has_Fixed_Op (T1, Op_Id)
4238 or else Nkind (Parent (N)) = N_Type_Conversion)
4240 Add_One_Interp (N, Op_Id, Universal_Fixed);
4242 elsif Is_Numeric_Type (T1)
4243 and then Is_Numeric_Type (T2)
4244 and then (Covers (T1 => T1, T2 => T2)
4246 Covers (T1 => T2, T2 => T1))
4248 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4250 elsif Is_Fixed_Point_Type (T1)
4251 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4252 or else T2 = Universal_Integer)
4254 Add_One_Interp (N, Op_Id, T1);
4256 elsif T2 = Universal_Real
4257 and then Base_Type (T1) = Base_Type (Standard_Integer)
4258 and then Op_Name = Name_Op_Multiply
4260 Add_One_Interp (N, Op_Id, Any_Fixed);
4262 elsif T1 = Universal_Real
4263 and then Base_Type (T2) = Base_Type (Standard_Integer)
4265 Add_One_Interp (N, Op_Id, Any_Fixed);
4267 elsif Is_Fixed_Point_Type (T2)
4268 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4269 or else T1 = Universal_Integer)
4270 and then Op_Name = Name_Op_Multiply
4272 Add_One_Interp (N, Op_Id, T2);
4274 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4275 Add_One_Interp (N, Op_Id, T1);
4277 elsif T2 = Universal_Real
4278 and then T1 = Universal_Integer
4279 and then Op_Name = Name_Op_Multiply
4281 Add_One_Interp (N, Op_Id, T2);
4284 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4286 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4287 -- set does not require any special processing, since the Etype is
4288 -- already set (case of operation constructed by Exp_Fixed).
4290 if Is_Integer_Type (T1)
4291 and then (Covers (T1 => T1, T2 => T2)
4293 Covers (T1 => T2, T2 => T1))
4295 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4298 elsif Op_Name = Name_Op_Expon then
4299 if Is_Numeric_Type (T1)
4300 and then not Is_Fixed_Point_Type (T1)
4301 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4302 or else T2 = Universal_Integer)
4304 Add_One_Interp (N, Op_Id, Base_Type (T1));
4307 else pragma Assert (Nkind (N) in N_Op_Shift);
4309 -- If not one of the predefined operators, the node may be one
4310 -- of the intrinsic functions. Its kind is always specific, and
4311 -- we can use it directly, rather than the name of the operation.
4313 if Is_Integer_Type (T1)
4314 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4315 or else T2 = Universal_Integer)
4317 Add_One_Interp (N, Op_Id, Base_Type (T1));
4320 end Check_Arithmetic_Pair;
4322 -------------------------------
4323 -- Check_Misspelled_Selector --
4324 -------------------------------
4326 procedure Check_Misspelled_Selector
4327 (Prefix : Entity_Id;
4330 Max_Suggestions : constant := 2;
4331 Nr_Of_Suggestions : Natural := 0;
4333 Suggestion_1 : Entity_Id := Empty;
4334 Suggestion_2 : Entity_Id := Empty;
4339 -- All the components of the prefix of selector Sel are matched
4340 -- against Sel and a count is maintained of possible misspellings.
4341 -- When at the end of the analysis there are one or two (not more!)
4342 -- possible misspellings, these misspellings will be suggested as
4343 -- possible correction.
4345 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4347 -- Concurrent types should be handled as well ???
4352 Comp := First_Entity (Prefix);
4353 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4354 if Is_Visible_Component (Comp) then
4355 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4356 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4358 case Nr_Of_Suggestions is
4359 when 1 => Suggestion_1 := Comp;
4360 when 2 => Suggestion_2 := Comp;
4361 when others => exit;
4366 Comp := Next_Entity (Comp);
4369 -- Report at most two suggestions
4371 if Nr_Of_Suggestions = 1 then
4372 Error_Msg_NE -- CODEFIX
4373 ("\possible misspelling of&", Sel, Suggestion_1);
4375 elsif Nr_Of_Suggestions = 2 then
4376 Error_Msg_Node_2 := Suggestion_2;
4377 Error_Msg_NE -- CODEFIX
4378 ("\possible misspelling of& or&", Sel, Suggestion_1);
4380 end Check_Misspelled_Selector;
4382 ----------------------
4383 -- Defined_In_Scope --
4384 ----------------------
4386 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4388 S1 : constant Entity_Id := Scope (Base_Type (T));
4391 or else (S1 = System_Aux_Id and then S = Scope (S1));
4392 end Defined_In_Scope;
4398 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4404 Void_Interp_Seen : Boolean := False;
4407 pragma Warnings (Off, Boolean);
4410 if Ada_Version >= Ada_05 then
4411 Actual := First_Actual (N);
4412 while Present (Actual) loop
4414 -- Ada 2005 (AI-50217): Post an error in case of premature
4415 -- usage of an entity from the limited view.
4417 if not Analyzed (Etype (Actual))
4418 and then From_With_Type (Etype (Actual))
4420 Error_Msg_Qual_Level := 1;
4422 ("missing with_clause for scope of imported type&",
4423 Actual, Etype (Actual));
4424 Error_Msg_Qual_Level := 0;
4427 Next_Actual (Actual);
4431 -- Analyze each candidate call again, with full error reporting
4435 ("no candidate interpretations match the actuals:!", Nam);
4436 Err_Mode := All_Errors_Mode;
4437 All_Errors_Mode := True;
4439 -- If this is a call to an operation of a concurrent type,
4440 -- the failed interpretations have been removed from the
4441 -- name. Recover them to provide full diagnostics.
4443 if Nkind (Parent (Nam)) = N_Selected_Component then
4444 Set_Entity (Nam, Empty);
4445 New_Nam := New_Copy_Tree (Parent (Nam));
4446 Set_Is_Overloaded (New_Nam, False);
4447 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4448 Set_Parent (New_Nam, Parent (Parent (Nam)));
4449 Analyze_Selected_Component (New_Nam);
4450 Get_First_Interp (Selector_Name (New_Nam), X, It);
4452 Get_First_Interp (Nam, X, It);
4455 while Present (It.Nam) loop
4456 if Etype (It.Nam) = Standard_Void_Type then
4457 Void_Interp_Seen := True;
4460 Analyze_One_Call (N, It.Nam, True, Success);
4461 Get_Next_Interp (X, It);
4464 if Nkind (N) = N_Function_Call then
4465 Get_First_Interp (Nam, X, It);
4466 while Present (It.Nam) loop
4467 if Ekind (It.Nam) = E_Function
4468 or else Ekind (It.Nam) = E_Operator
4472 Get_Next_Interp (X, It);
4476 -- If all interpretations are procedures, this deserves a
4477 -- more precise message. Ditto if this appears as the prefix
4478 -- of a selected component, which may be a lexical error.
4481 ("\context requires function call, found procedure name", Nam);
4483 if Nkind (Parent (N)) = N_Selected_Component
4484 and then N = Prefix (Parent (N))
4486 Error_Msg_N -- CODEFIX
4487 ("\period should probably be semicolon", Parent (N));
4490 elsif Nkind (N) = N_Procedure_Call_Statement
4491 and then not Void_Interp_Seen
4494 "\function name found in procedure call", Nam);
4497 All_Errors_Mode := Err_Mode;
4500 ---------------------------
4501 -- Find_Arithmetic_Types --
4502 ---------------------------
4504 procedure Find_Arithmetic_Types
4509 Index1 : Interp_Index;
4510 Index2 : Interp_Index;
4514 procedure Check_Right_Argument (T : Entity_Id);
4515 -- Check right operand of operator
4517 --------------------------
4518 -- Check_Right_Argument --
4519 --------------------------
4521 procedure Check_Right_Argument (T : Entity_Id) is
4523 if not Is_Overloaded (R) then
4524 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4526 Get_First_Interp (R, Index2, It2);
4527 while Present (It2.Typ) loop
4528 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4529 Get_Next_Interp (Index2, It2);
4532 end Check_Right_Argument;
4534 -- Start of processing for Find_Arithmetic_Types
4537 if not Is_Overloaded (L) then
4538 Check_Right_Argument (Etype (L));
4541 Get_First_Interp (L, Index1, It1);
4542 while Present (It1.Typ) loop
4543 Check_Right_Argument (It1.Typ);
4544 Get_Next_Interp (Index1, It1);
4548 end Find_Arithmetic_Types;
4550 ------------------------
4551 -- Find_Boolean_Types --
4552 ------------------------
4554 procedure Find_Boolean_Types
4559 Index : Interp_Index;
4562 procedure Check_Numeric_Argument (T : Entity_Id);
4563 -- Special case for logical operations one of whose operands is an
4564 -- integer literal. If both are literal the result is any modular type.
4566 ----------------------------
4567 -- Check_Numeric_Argument --
4568 ----------------------------
4570 procedure Check_Numeric_Argument (T : Entity_Id) is
4572 if T = Universal_Integer then
4573 Add_One_Interp (N, Op_Id, Any_Modular);
4575 elsif Is_Modular_Integer_Type (T) then
4576 Add_One_Interp (N, Op_Id, T);
4578 end Check_Numeric_Argument;
4580 -- Start of processing for Find_Boolean_Types
4583 if not Is_Overloaded (L) then
4584 if Etype (L) = Universal_Integer
4585 or else Etype (L) = Any_Modular
4587 if not Is_Overloaded (R) then
4588 Check_Numeric_Argument (Etype (R));
4591 Get_First_Interp (R, Index, It);
4592 while Present (It.Typ) loop
4593 Check_Numeric_Argument (It.Typ);
4594 Get_Next_Interp (Index, It);
4598 -- If operands are aggregates, we must assume that they may be
4599 -- boolean arrays, and leave disambiguation for the second pass.
4600 -- If only one is an aggregate, verify that the other one has an
4601 -- interpretation as a boolean array
4603 elsif Nkind (L) = N_Aggregate then
4604 if Nkind (R) = N_Aggregate then
4605 Add_One_Interp (N, Op_Id, Etype (L));
4607 elsif not Is_Overloaded (R) then
4608 if Valid_Boolean_Arg (Etype (R)) then
4609 Add_One_Interp (N, Op_Id, Etype (R));
4613 Get_First_Interp (R, Index, It);
4614 while Present (It.Typ) loop
4615 if Valid_Boolean_Arg (It.Typ) then
4616 Add_One_Interp (N, Op_Id, It.Typ);
4619 Get_Next_Interp (Index, It);
4623 elsif Valid_Boolean_Arg (Etype (L))
4624 and then Has_Compatible_Type (R, Etype (L))
4626 Add_One_Interp (N, Op_Id, Etype (L));
4630 Get_First_Interp (L, Index, It);
4631 while Present (It.Typ) loop
4632 if Valid_Boolean_Arg (It.Typ)
4633 and then Has_Compatible_Type (R, It.Typ)
4635 Add_One_Interp (N, Op_Id, It.Typ);
4638 Get_Next_Interp (Index, It);
4641 end Find_Boolean_Types;
4643 ---------------------------
4644 -- Find_Comparison_Types --
4645 ---------------------------
4647 procedure Find_Comparison_Types
4652 Index : Interp_Index;
4654 Found : Boolean := False;
4657 Scop : Entity_Id := Empty;
4659 procedure Try_One_Interp (T1 : Entity_Id);
4660 -- Routine to try one proposed interpretation. Note that the context
4661 -- of the operator plays no role in resolving the arguments, so that
4662 -- if there is more than one interpretation of the operands that is
4663 -- compatible with comparison, the operation is ambiguous.
4665 --------------------
4666 -- Try_One_Interp --
4667 --------------------
4669 procedure Try_One_Interp (T1 : Entity_Id) is
4672 -- If the operator is an expanded name, then the type of the operand
4673 -- must be defined in the corresponding scope. If the type is
4674 -- universal, the context will impose the correct type.
4677 and then not Defined_In_Scope (T1, Scop)
4678 and then T1 /= Universal_Integer
4679 and then T1 /= Universal_Real
4680 and then T1 /= Any_String
4681 and then T1 /= Any_Composite
4686 if Valid_Comparison_Arg (T1)
4687 and then Has_Compatible_Type (R, T1)
4690 and then Base_Type (T1) /= Base_Type (T_F)
4692 It := Disambiguate (L, I_F, Index, Any_Type);
4694 if It = No_Interp then
4695 Ambiguous_Operands (N);
4696 Set_Etype (L, Any_Type);
4710 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4715 -- Start of processing for Find_Comparison_Types
4718 -- If left operand is aggregate, the right operand has to
4719 -- provide a usable type for it.
4721 if Nkind (L) = N_Aggregate
4722 and then Nkind (R) /= N_Aggregate
4724 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4728 if Nkind (N) = N_Function_Call
4729 and then Nkind (Name (N)) = N_Expanded_Name
4731 Scop := Entity (Prefix (Name (N)));
4733 -- The prefix may be a package renaming, and the subsequent test
4734 -- requires the original package.
4736 if Ekind (Scop) = E_Package
4737 and then Present (Renamed_Entity (Scop))
4739 Scop := Renamed_Entity (Scop);
4740 Set_Entity (Prefix (Name (N)), Scop);
4744 if not Is_Overloaded (L) then
4745 Try_One_Interp (Etype (L));
4748 Get_First_Interp (L, Index, It);
4749 while Present (It.Typ) loop
4750 Try_One_Interp (It.Typ);
4751 Get_Next_Interp (Index, It);
4754 end Find_Comparison_Types;
4756 ----------------------------------------
4757 -- Find_Non_Universal_Interpretations --
4758 ----------------------------------------
4760 procedure Find_Non_Universal_Interpretations
4766 Index : Interp_Index;
4770 if T1 = Universal_Integer
4771 or else T1 = Universal_Real
4773 if not Is_Overloaded (R) then
4775 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
4777 Get_First_Interp (R, Index, It);
4778 while Present (It.Typ) loop
4779 if Covers (It.Typ, T1) then
4781 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
4784 Get_Next_Interp (Index, It);
4788 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
4790 end Find_Non_Universal_Interpretations;
4792 ------------------------------
4793 -- Find_Concatenation_Types --
4794 ------------------------------
4796 procedure Find_Concatenation_Types
4801 Op_Type : constant Entity_Id := Etype (Op_Id);
4804 if Is_Array_Type (Op_Type)
4805 and then not Is_Limited_Type (Op_Type)
4807 and then (Has_Compatible_Type (L, Op_Type)
4809 Has_Compatible_Type (L, Component_Type (Op_Type)))
4811 and then (Has_Compatible_Type (R, Op_Type)
4813 Has_Compatible_Type (R, Component_Type (Op_Type)))
4815 Add_One_Interp (N, Op_Id, Op_Type);
4817 end Find_Concatenation_Types;
4819 -------------------------
4820 -- Find_Equality_Types --
4821 -------------------------
4823 procedure Find_Equality_Types
4828 Index : Interp_Index;
4830 Found : Boolean := False;
4833 Scop : Entity_Id := Empty;
4835 procedure Try_One_Interp (T1 : Entity_Id);
4836 -- The context of the equality operator plays no role in resolving the
4837 -- arguments, so that if there is more than one interpretation of the
4838 -- operands that is compatible with equality, the construct is ambiguous
4839 -- and an error can be emitted now, after trying to disambiguate, i.e.
4840 -- applying preference rules.
4842 --------------------
4843 -- Try_One_Interp --
4844 --------------------
4846 procedure Try_One_Interp (T1 : Entity_Id) is
4847 Bas : constant Entity_Id := Base_Type (T1);
4850 -- If the operator is an expanded name, then the type of the operand
4851 -- must be defined in the corresponding scope. If the type is
4852 -- universal, the context will impose the correct type. An anonymous
4853 -- type for a 'Access reference is also universal in this sense, as
4854 -- the actual type is obtained from context.
4855 -- In Ada 2005, the equality operator for anonymous access types
4856 -- is declared in Standard, and preference rules apply to it.
4858 if Present (Scop) then
4859 if Defined_In_Scope (T1, Scop)
4860 or else T1 = Universal_Integer
4861 or else T1 = Universal_Real
4862 or else T1 = Any_Access
4863 or else T1 = Any_String
4864 or else T1 = Any_Composite
4865 or else (Ekind (T1) = E_Access_Subprogram_Type
4866 and then not Comes_From_Source (T1))
4870 elsif Ekind (T1) = E_Anonymous_Access_Type
4871 and then Scop = Standard_Standard
4876 -- The scope does not contain an operator for the type
4881 -- If we have infix notation, the operator must be usable.
4882 -- Within an instance, if the type is already established we
4883 -- know it is correct.
4884 -- In Ada 2005, the equality on anonymous access types is declared
4885 -- in Standard, and is always visible.
4887 elsif In_Open_Scopes (Scope (Bas))
4888 or else Is_Potentially_Use_Visible (Bas)
4889 or else In_Use (Bas)
4890 or else (In_Use (Scope (Bas))
4891 and then not Is_Hidden (Bas))
4892 or else (In_Instance
4893 and then First_Subtype (T1) = First_Subtype (Etype (R)))
4894 or else Ekind (T1) = E_Anonymous_Access_Type
4899 -- Save candidate type for subsquent error message, if any
4901 if not Is_Limited_Type (T1) then
4902 Candidate_Type := T1;
4908 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
4909 -- Do not allow anonymous access types in equality operators.
4911 if Ada_Version < Ada_05
4912 and then Ekind (T1) = E_Anonymous_Access_Type
4917 if T1 /= Standard_Void_Type
4918 and then not Is_Limited_Type (T1)
4919 and then not Is_Limited_Composite (T1)
4920 and then Has_Compatible_Type (R, T1)
4923 and then Base_Type (T1) /= Base_Type (T_F)
4925 It := Disambiguate (L, I_F, Index, Any_Type);
4927 if It = No_Interp then
4928 Ambiguous_Operands (N);
4929 Set_Etype (L, Any_Type);
4942 if not Analyzed (L) then
4946 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4948 -- Case of operator was not visible, Etype still set to Any_Type
4950 if Etype (N) = Any_Type then
4954 elsif Scop = Standard_Standard
4955 and then Ekind (T1) = E_Anonymous_Access_Type
4961 -- Start of processing for Find_Equality_Types
4964 -- If left operand is aggregate, the right operand has to
4965 -- provide a usable type for it.
4967 if Nkind (L) = N_Aggregate
4968 and then Nkind (R) /= N_Aggregate
4970 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4974 if Nkind (N) = N_Function_Call
4975 and then Nkind (Name (N)) = N_Expanded_Name
4977 Scop := Entity (Prefix (Name (N)));
4979 -- The prefix may be a package renaming, and the subsequent test
4980 -- requires the original package.
4982 if Ekind (Scop) = E_Package
4983 and then Present (Renamed_Entity (Scop))
4985 Scop := Renamed_Entity (Scop);
4986 Set_Entity (Prefix (Name (N)), Scop);
4990 if not Is_Overloaded (L) then
4991 Try_One_Interp (Etype (L));
4994 Get_First_Interp (L, Index, It);
4995 while Present (It.Typ) loop
4996 Try_One_Interp (It.Typ);
4997 Get_Next_Interp (Index, It);
5000 end Find_Equality_Types;
5002 -------------------------
5003 -- Find_Negation_Types --
5004 -------------------------
5006 procedure Find_Negation_Types
5011 Index : Interp_Index;
5015 if not Is_Overloaded (R) then
5016 if Etype (R) = Universal_Integer then
5017 Add_One_Interp (N, Op_Id, Any_Modular);
5018 elsif Valid_Boolean_Arg (Etype (R)) then
5019 Add_One_Interp (N, Op_Id, Etype (R));
5023 Get_First_Interp (R, Index, It);
5024 while Present (It.Typ) loop
5025 if Valid_Boolean_Arg (It.Typ) then
5026 Add_One_Interp (N, Op_Id, It.Typ);
5029 Get_Next_Interp (Index, It);
5032 end Find_Negation_Types;
5034 ------------------------------
5035 -- Find_Primitive_Operation --
5036 ------------------------------
5038 function Find_Primitive_Operation (N : Node_Id) return Boolean is
5039 Obj : constant Node_Id := Prefix (N);
5040 Op : constant Node_Id := Selector_Name (N);
5047 Set_Etype (Op, Any_Type);
5049 if Is_Access_Type (Etype (Obj)) then
5050 Typ := Designated_Type (Etype (Obj));
5055 if Is_Class_Wide_Type (Typ) then
5056 Typ := Root_Type (Typ);
5059 Prims := Primitive_Operations (Typ);
5061 Prim := First_Elmt (Prims);
5062 while Present (Prim) loop
5063 if Chars (Node (Prim)) = Chars (Op) then
5064 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
5065 Set_Etype (N, Etype (Node (Prim)));
5071 -- Now look for class-wide operations of the type or any of its
5072 -- ancestors by iterating over the homonyms of the selector.
5075 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
5079 Hom := Current_Entity (Op);
5080 while Present (Hom) loop
5081 if (Ekind (Hom) = E_Procedure
5083 Ekind (Hom) = E_Function)
5084 and then Scope (Hom) = Scope (Typ)
5085 and then Present (First_Formal (Hom))
5087 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
5089 (Is_Access_Type (Etype (First_Formal (Hom)))
5091 Ekind (Etype (First_Formal (Hom))) =
5092 E_Anonymous_Access_Type
5095 (Designated_Type (Etype (First_Formal (Hom)))) =
5098 Add_One_Interp (Op, Hom, Etype (Hom));
5099 Set_Etype (N, Etype (Hom));
5102 Hom := Homonym (Hom);
5106 return Etype (Op) /= Any_Type;
5107 end Find_Primitive_Operation;
5109 ----------------------
5110 -- Find_Unary_Types --
5111 ----------------------
5113 procedure Find_Unary_Types
5118 Index : Interp_Index;
5122 if not Is_Overloaded (R) then
5123 if Is_Numeric_Type (Etype (R)) then
5124 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
5128 Get_First_Interp (R, Index, It);
5129 while Present (It.Typ) loop
5130 if Is_Numeric_Type (It.Typ) then
5131 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
5134 Get_Next_Interp (Index, It);
5137 end Find_Unary_Types;
5143 function Junk_Operand (N : Node_Id) return Boolean is
5147 if Error_Posted (N) then
5151 -- Get entity to be tested
5153 if Is_Entity_Name (N)
5154 and then Present (Entity (N))
5158 -- An odd case, a procedure name gets converted to a very peculiar
5159 -- function call, and here is where we detect this happening.
5161 elsif Nkind (N) = N_Function_Call
5162 and then Is_Entity_Name (Name (N))
5163 and then Present (Entity (Name (N)))
5167 -- Another odd case, there are at least some cases of selected
5168 -- components where the selected component is not marked as having
5169 -- an entity, even though the selector does have an entity
5171 elsif Nkind (N) = N_Selected_Component
5172 and then Present (Entity (Selector_Name (N)))
5174 Enode := Selector_Name (N);
5180 -- Now test the entity we got to see if it is a bad case
5182 case Ekind (Entity (Enode)) is
5186 ("package name cannot be used as operand", Enode);
5188 when Generic_Unit_Kind =>
5190 ("generic unit name cannot be used as operand", Enode);
5194 ("subtype name cannot be used as operand", Enode);
5198 ("entry name cannot be used as operand", Enode);
5202 ("procedure name cannot be used as operand", Enode);
5206 ("exception name cannot be used as operand", Enode);
5208 when E_Block | E_Label | E_Loop =>
5210 ("label name cannot be used as operand", Enode);
5220 --------------------
5221 -- Operator_Check --
5222 --------------------
5224 procedure Operator_Check (N : Node_Id) is
5226 Remove_Abstract_Operations (N);
5228 -- Test for case of no interpretation found for operator
5230 if Etype (N) = Any_Type then
5234 Op_Id : Entity_Id := Empty;
5237 R := Right_Opnd (N);
5239 if Nkind (N) in N_Binary_Op then
5245 -- If either operand has no type, then don't complain further,
5246 -- since this simply means that we have a propagated error.
5249 or else Etype (R) = Any_Type
5250 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5254 -- We explicitly check for the case of concatenation of component
5255 -- with component to avoid reporting spurious matching array types
5256 -- that might happen to be lurking in distant packages (such as
5257 -- run-time packages). This also prevents inconsistencies in the
5258 -- messages for certain ACVC B tests, which can vary depending on
5259 -- types declared in run-time interfaces. Another improvement when
5260 -- aggregates are present is to look for a well-typed operand.
5262 elsif Present (Candidate_Type)
5263 and then (Nkind (N) /= N_Op_Concat
5264 or else Is_Array_Type (Etype (L))
5265 or else Is_Array_Type (Etype (R)))
5268 if Nkind (N) = N_Op_Concat then
5269 if Etype (L) /= Any_Composite
5270 and then Is_Array_Type (Etype (L))
5272 Candidate_Type := Etype (L);
5274 elsif Etype (R) /= Any_Composite
5275 and then Is_Array_Type (Etype (R))
5277 Candidate_Type := Etype (R);
5282 ("operator for} is not directly visible!",
5283 N, First_Subtype (Candidate_Type));
5284 Error_Msg_N ("use clause would make operation legal!", N);
5287 -- If either operand is a junk operand (e.g. package name), then
5288 -- post appropriate error messages, but do not complain further.
5290 -- Note that the use of OR in this test instead of OR ELSE is
5291 -- quite deliberate, we may as well check both operands in the
5292 -- binary operator case.
5294 elsif Junk_Operand (R)
5295 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5299 -- If we have a logical operator, one of whose operands is
5300 -- Boolean, then we know that the other operand cannot resolve to
5301 -- Boolean (since we got no interpretations), but in that case we
5302 -- pretty much know that the other operand should be Boolean, so
5303 -- resolve it that way (generating an error)
5305 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5306 if Etype (L) = Standard_Boolean then
5307 Resolve (R, Standard_Boolean);
5309 elsif Etype (R) = Standard_Boolean then
5310 Resolve (L, Standard_Boolean);
5314 -- For an arithmetic operator or comparison operator, if one
5315 -- of the operands is numeric, then we know the other operand
5316 -- is not the same numeric type. If it is a non-numeric type,
5317 -- then probably it is intended to match the other operand.
5319 elsif Nkind_In (N, N_Op_Add,
5325 Nkind_In (N, N_Op_Lt,
5331 if Is_Numeric_Type (Etype (L))
5332 and then not Is_Numeric_Type (Etype (R))
5334 Resolve (R, Etype (L));
5337 elsif Is_Numeric_Type (Etype (R))
5338 and then not Is_Numeric_Type (Etype (L))
5340 Resolve (L, Etype (R));
5344 -- Comparisons on A'Access are common enough to deserve a
5347 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5348 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5349 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5352 ("two access attributes cannot be compared directly", N);
5354 ("\use qualified expression for one of the operands",
5358 -- Another one for C programmers
5360 elsif Nkind (N) = N_Op_Concat
5361 and then Valid_Boolean_Arg (Etype (L))
5362 and then Valid_Boolean_Arg (Etype (R))
5364 Error_Msg_N ("invalid operands for concatenation", N);
5365 Error_Msg_N -- CODEFIX
5366 ("\maybe AND was meant", N);
5369 -- A special case for comparison of access parameter with null
5371 elsif Nkind (N) = N_Op_Eq
5372 and then Is_Entity_Name (L)
5373 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5374 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5376 and then Nkind (R) = N_Null
5378 Error_Msg_N ("access parameter is not allowed to be null", L);
5379 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5382 -- Another special case for exponentiation, where the right
5383 -- operand must be Natural, independently of the base.
5385 elsif Nkind (N) = N_Op_Expon
5386 and then Is_Numeric_Type (Etype (L))
5387 and then not Is_Overloaded (R)
5389 First_Subtype (Base_Type (Etype (R))) /= Standard_Integer
5390 and then Base_Type (Etype (R)) /= Universal_Integer
5393 ("exponent must be of type Natural, found}", R, Etype (R));
5397 -- If we fall through then just give general message. Note that in
5398 -- the following messages, if the operand is overloaded we choose
5399 -- an arbitrary type to complain about, but that is probably more
5400 -- useful than not giving a type at all.
5402 if Nkind (N) in N_Unary_Op then
5403 Error_Msg_Node_2 := Etype (R);
5404 Error_Msg_N ("operator& not defined for}", N);
5408 if Nkind (N) in N_Binary_Op then
5409 if not Is_Overloaded (L)
5410 and then not Is_Overloaded (R)
5411 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5413 Error_Msg_Node_2 := First_Subtype (Etype (R));
5414 Error_Msg_N ("there is no applicable operator& for}", N);
5417 -- Another attempt to find a fix: one of the candidate
5418 -- interpretations may not be use-visible. This has
5419 -- already been checked for predefined operators, so
5420 -- we examine only user-defined functions.
5422 Op_Id := Get_Name_Entity_Id (Chars (N));
5424 while Present (Op_Id) loop
5425 if Ekind (Op_Id) /= E_Operator
5426 and then Is_Overloadable (Op_Id)
5428 if not Is_Immediately_Visible (Op_Id)
5429 and then not In_Use (Scope (Op_Id))
5430 and then not Is_Abstract_Subprogram (Op_Id)
5431 and then not Is_Hidden (Op_Id)
5432 and then Ekind (Scope (Op_Id)) = E_Package
5435 (L, Etype (First_Formal (Op_Id)))
5437 (Next_Formal (First_Formal (Op_Id)))
5441 Etype (Next_Formal (First_Formal (Op_Id))))
5444 ("No legal interpretation for operator&", N);
5446 ("\use clause on& would make operation legal",
5452 Op_Id := Homonym (Op_Id);
5456 Error_Msg_N ("invalid operand types for operator&", N);
5458 if Nkind (N) /= N_Op_Concat then
5459 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5460 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5470 -----------------------------------------
5471 -- Process_Implicit_Dereference_Prefix --
5472 -----------------------------------------
5474 function Process_Implicit_Dereference_Prefix
5476 P : Entity_Id) return Entity_Id
5479 Typ : constant Entity_Id := Designated_Type (Etype (P));
5483 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5485 -- We create a dummy reference to E to ensure that the reference
5486 -- is not considered as part of an assignment (an implicit
5487 -- dereference can never assign to its prefix). The Comes_From_Source
5488 -- attribute needs to be propagated for accurate warnings.
5490 Ref := New_Reference_To (E, Sloc (P));
5491 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5492 Generate_Reference (E, Ref);
5495 -- An implicit dereference is a legal occurrence of an
5496 -- incomplete type imported through a limited_with clause,
5497 -- if the full view is visible.
5499 if From_With_Type (Typ)
5500 and then not From_With_Type (Scope (Typ))
5502 (Is_Immediately_Visible (Scope (Typ))
5504 (Is_Child_Unit (Scope (Typ))
5505 and then Is_Visible_Child_Unit (Scope (Typ))))
5507 return Available_View (Typ);
5512 end Process_Implicit_Dereference_Prefix;
5514 --------------------------------
5515 -- Remove_Abstract_Operations --
5516 --------------------------------
5518 procedure Remove_Abstract_Operations (N : Node_Id) is
5519 Abstract_Op : Entity_Id := Empty;
5520 Address_Kludge : Boolean := False;
5524 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5525 -- activate this if either extensions are enabled, or if the abstract
5526 -- operation in question comes from a predefined file. This latter test
5527 -- allows us to use abstract to make operations invisible to users. In
5528 -- particular, if type Address is non-private and abstract subprograms
5529 -- are used to hide its operators, they will be truly hidden.
5531 type Operand_Position is (First_Op, Second_Op);
5532 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5534 procedure Remove_Address_Interpretations (Op : Operand_Position);
5535 -- Ambiguities may arise when the operands are literal and the address
5536 -- operations in s-auxdec are visible. In that case, remove the
5537 -- interpretation of a literal as Address, to retain the semantics of
5538 -- Address as a private type.
5540 ------------------------------------
5541 -- Remove_Address_Interpretations --
5542 ------------------------------------
5544 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5548 if Is_Overloaded (N) then
5549 Get_First_Interp (N, I, It);
5550 while Present (It.Nam) loop
5551 Formal := First_Entity (It.Nam);
5553 if Op = Second_Op then
5554 Formal := Next_Entity (Formal);
5557 if Is_Descendent_Of_Address (Etype (Formal)) then
5558 Address_Kludge := True;
5562 Get_Next_Interp (I, It);
5565 end Remove_Address_Interpretations;
5567 -- Start of processing for Remove_Abstract_Operations
5570 if Is_Overloaded (N) then
5571 Get_First_Interp (N, I, It);
5573 while Present (It.Nam) loop
5574 if Is_Overloadable (It.Nam)
5575 and then Is_Abstract_Subprogram (It.Nam)
5576 and then not Is_Dispatching_Operation (It.Nam)
5578 Abstract_Op := It.Nam;
5580 if Is_Descendent_Of_Address (It.Typ) then
5581 Address_Kludge := True;
5585 -- In Ada 2005, this operation does not participate in Overload
5586 -- resolution. If the operation is defined in a predefined
5587 -- unit, it is one of the operations declared abstract in some
5588 -- variants of System, and it must be removed as well.
5590 elsif Ada_Version >= Ada_05
5591 or else Is_Predefined_File_Name
5592 (Unit_File_Name (Get_Source_Unit (It.Nam)))
5599 Get_Next_Interp (I, It);
5602 if No (Abstract_Op) then
5604 -- If some interpretation yields an integer type, it is still
5605 -- possible that there are address interpretations. Remove them
5606 -- if one operand is a literal, to avoid spurious ambiguities
5607 -- on systems where Address is a visible integer type.
5609 if Is_Overloaded (N)
5610 and then Nkind (N) in N_Op
5611 and then Is_Integer_Type (Etype (N))
5613 if Nkind (N) in N_Binary_Op then
5614 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
5615 Remove_Address_Interpretations (Second_Op);
5617 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
5618 Remove_Address_Interpretations (First_Op);
5623 elsif Nkind (N) in N_Op then
5625 -- Remove interpretations that treat literals as addresses. This
5626 -- is never appropriate, even when Address is defined as a visible
5627 -- Integer type. The reason is that we would really prefer Address
5628 -- to behave as a private type, even in this case, which is there
5629 -- only to accommodate oddities of VMS address sizes. If Address
5630 -- is a visible integer type, we get lots of overload ambiguities.
5632 if Nkind (N) in N_Binary_Op then
5634 U1 : constant Boolean :=
5635 Present (Universal_Interpretation (Right_Opnd (N)));
5636 U2 : constant Boolean :=
5637 Present (Universal_Interpretation (Left_Opnd (N)));
5641 Remove_Address_Interpretations (Second_Op);
5645 Remove_Address_Interpretations (First_Op);
5648 if not (U1 and U2) then
5650 -- Remove corresponding predefined operator, which is
5651 -- always added to the overload set.
5653 Get_First_Interp (N, I, It);
5654 while Present (It.Nam) loop
5655 if Scope (It.Nam) = Standard_Standard
5656 and then Base_Type (It.Typ) =
5657 Base_Type (Etype (Abstract_Op))
5662 Get_Next_Interp (I, It);
5665 elsif Is_Overloaded (N)
5666 and then Present (Univ_Type)
5668 -- If both operands have a universal interpretation,
5669 -- it is still necessary to remove interpretations that
5670 -- yield Address. Any remaining ambiguities will be
5671 -- removed in Disambiguate.
5673 Get_First_Interp (N, I, It);
5674 while Present (It.Nam) loop
5675 if Is_Descendent_Of_Address (It.Typ) then
5678 elsif not Is_Type (It.Nam) then
5679 Set_Entity (N, It.Nam);
5682 Get_Next_Interp (I, It);
5688 elsif Nkind (N) = N_Function_Call
5690 (Nkind (Name (N)) = N_Operator_Symbol
5692 (Nkind (Name (N)) = N_Expanded_Name
5694 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
5698 Arg1 : constant Node_Id := First (Parameter_Associations (N));
5699 U1 : constant Boolean :=
5700 Present (Universal_Interpretation (Arg1));
5701 U2 : constant Boolean :=
5702 Present (Next (Arg1)) and then
5703 Present (Universal_Interpretation (Next (Arg1)));
5707 Remove_Address_Interpretations (First_Op);
5711 Remove_Address_Interpretations (Second_Op);
5714 if not (U1 and U2) then
5715 Get_First_Interp (N, I, It);
5716 while Present (It.Nam) loop
5717 if Scope (It.Nam) = Standard_Standard
5718 and then It.Typ = Base_Type (Etype (Abstract_Op))
5723 Get_Next_Interp (I, It);
5729 -- If the removal has left no valid interpretations, emit an error
5730 -- message now and label node as illegal.
5732 if Present (Abstract_Op) then
5733 Get_First_Interp (N, I, It);
5737 -- Removal of abstract operation left no viable candidate
5739 Set_Etype (N, Any_Type);
5740 Error_Msg_Sloc := Sloc (Abstract_Op);
5742 ("cannot call abstract operation& declared#", N, Abstract_Op);
5744 -- In Ada 2005, an abstract operation may disable predefined
5745 -- operators. Since the context is not yet known, we mark the
5746 -- predefined operators as potentially hidden. Do not include
5747 -- predefined operators when addresses are involved since this
5748 -- case is handled separately.
5750 elsif Ada_Version >= Ada_05
5751 and then not Address_Kludge
5753 while Present (It.Nam) loop
5754 if Is_Numeric_Type (It.Typ)
5755 and then Scope (It.Typ) = Standard_Standard
5757 Set_Abstract_Op (I, Abstract_Op);
5760 Get_Next_Interp (I, It);
5765 end Remove_Abstract_Operations;
5767 -----------------------
5768 -- Try_Indirect_Call --
5769 -----------------------
5771 function Try_Indirect_Call
5774 Typ : Entity_Id) return Boolean
5780 pragma Warnings (Off, Call_OK);
5783 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
5785 Actual := First_Actual (N);
5786 Formal := First_Formal (Designated_Type (Typ));
5787 while Present (Actual) and then Present (Formal) loop
5788 if not Has_Compatible_Type (Actual, Etype (Formal)) then
5793 Next_Formal (Formal);
5796 if No (Actual) and then No (Formal) then
5797 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
5799 -- Nam is a candidate interpretation for the name in the call,
5800 -- if it is not an indirect call.
5802 if not Is_Type (Nam)
5803 and then Is_Entity_Name (Name (N))
5805 Set_Entity (Name (N), Nam);
5812 end Try_Indirect_Call;
5814 ----------------------
5815 -- Try_Indexed_Call --
5816 ----------------------
5818 function Try_Indexed_Call
5822 Skip_First : Boolean) return Boolean
5824 Loc : constant Source_Ptr := Sloc (N);
5825 Actuals : constant List_Id := Parameter_Associations (N);
5830 Actual := First (Actuals);
5832 -- If the call was originally written in prefix form, skip the first
5833 -- actual, which is obviously not defaulted.
5839 Index := First_Index (Typ);
5840 while Present (Actual) and then Present (Index) loop
5842 -- If the parameter list has a named association, the expression
5843 -- is definitely a call and not an indexed component.
5845 if Nkind (Actual) = N_Parameter_Association then
5849 if Is_Entity_Name (Actual)
5850 and then Is_Type (Entity (Actual))
5851 and then No (Next (Actual))
5855 Prefix => Make_Function_Call (Loc,
5856 Name => Relocate_Node (Name (N))),
5858 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
5863 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
5871 if No (Actual) and then No (Index) then
5872 Add_One_Interp (N, Nam, Component_Type (Typ));
5874 -- Nam is a candidate interpretation for the name in the call,
5875 -- if it is not an indirect call.
5877 if not Is_Type (Nam)
5878 and then Is_Entity_Name (Name (N))
5880 Set_Entity (Name (N), Nam);
5887 end Try_Indexed_Call;
5889 --------------------------
5890 -- Try_Object_Operation --
5891 --------------------------
5893 function Try_Object_Operation (N : Node_Id) return Boolean is
5894 K : constant Node_Kind := Nkind (Parent (N));
5895 Is_Subprg_Call : constant Boolean := Nkind_In
5896 (K, N_Procedure_Call_Statement,
5898 Loc : constant Source_Ptr := Sloc (N);
5899 Obj : constant Node_Id := Prefix (N);
5900 Subprog : constant Node_Id :=
5901 Make_Identifier (Sloc (Selector_Name (N)),
5902 Chars => Chars (Selector_Name (N)));
5903 -- Identifier on which possible interpretations will be collected
5905 Report_Error : Boolean := False;
5906 -- If no candidate interpretation matches the context, redo the
5907 -- analysis with error enabled to provide additional information.
5910 Candidate : Entity_Id := Empty;
5911 New_Call_Node : Node_Id := Empty;
5912 Node_To_Replace : Node_Id;
5913 Obj_Type : Entity_Id := Etype (Obj);
5914 Success : Boolean := False;
5916 function Valid_Candidate
5919 Subp : Entity_Id) return Entity_Id;
5920 -- If the subprogram is a valid interpretation, record it, and add
5921 -- to the list of interpretations of Subprog.
5923 procedure Complete_Object_Operation
5924 (Call_Node : Node_Id;
5925 Node_To_Replace : Node_Id);
5926 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
5927 -- Call_Node, insert the object (or its dereference) as the first actual
5928 -- in the call, and complete the analysis of the call.
5930 procedure Report_Ambiguity (Op : Entity_Id);
5931 -- If a prefixed procedure call is ambiguous, indicate whether the
5932 -- call includes an implicit dereference or an implicit 'Access.
5934 procedure Transform_Object_Operation
5935 (Call_Node : out Node_Id;
5936 Node_To_Replace : out Node_Id);
5937 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
5938 -- Call_Node is the resulting subprogram call, Node_To_Replace is
5939 -- either N or the parent of N, and Subprog is a reference to the
5940 -- subprogram we are trying to match.
5942 function Try_Class_Wide_Operation
5943 (Call_Node : Node_Id;
5944 Node_To_Replace : Node_Id) return Boolean;
5945 -- Traverse all ancestor types looking for a class-wide subprogram
5946 -- for which the current operation is a valid non-dispatching call.
5948 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
5949 -- If prefix is overloaded, its interpretation may include different
5950 -- tagged types, and we must examine the primitive operations and
5951 -- the class-wide operations of each in order to find candidate
5952 -- interpretations for the call as a whole.
5954 function Try_Primitive_Operation
5955 (Call_Node : Node_Id;
5956 Node_To_Replace : Node_Id) return Boolean;
5957 -- Traverse the list of primitive subprograms looking for a dispatching
5958 -- operation for which the current node is a valid call .
5960 ---------------------
5961 -- Valid_Candidate --
5962 ---------------------
5964 function Valid_Candidate
5967 Subp : Entity_Id) return Entity_Id
5969 Arr_Type : Entity_Id;
5970 Comp_Type : Entity_Id;
5973 -- If the subprogram is a valid interpretation, record it in global
5974 -- variable Subprog, to collect all possible overloadings.
5977 if Subp /= Entity (Subprog) then
5978 Add_One_Interp (Subprog, Subp, Etype (Subp));
5982 -- If the call may be an indexed call, retrieve component type of
5983 -- resulting expression, and add possible interpretation.
5988 if Nkind (Call) = N_Function_Call
5989 and then Nkind (Parent (N)) = N_Indexed_Component
5990 and then Needs_One_Actual (Subp)
5992 if Is_Array_Type (Etype (Subp)) then
5993 Arr_Type := Etype (Subp);
5995 elsif Is_Access_Type (Etype (Subp))
5996 and then Is_Array_Type (Designated_Type (Etype (Subp)))
5998 Arr_Type := Designated_Type (Etype (Subp));
6002 if Present (Arr_Type) then
6004 -- Verify that the actuals (excluding the object)
6005 -- match the types of the indices.
6012 Actual := Next (First_Actual (Call));
6013 Index := First_Index (Arr_Type);
6014 while Present (Actual) and then Present (Index) loop
6015 if not Has_Compatible_Type (Actual, Etype (Index)) then
6020 Next_Actual (Actual);
6026 and then Present (Arr_Type)
6028 Comp_Type := Component_Type (Arr_Type);
6032 if Present (Comp_Type)
6033 and then Etype (Subprog) /= Comp_Type
6035 Add_One_Interp (Subprog, Subp, Comp_Type);
6039 if Etype (Call) /= Any_Type then
6044 end Valid_Candidate;
6046 -------------------------------
6047 -- Complete_Object_Operation --
6048 -------------------------------
6050 procedure Complete_Object_Operation
6051 (Call_Node : Node_Id;
6052 Node_To_Replace : Node_Id)
6054 Control : constant Entity_Id := First_Formal (Entity (Subprog));
6055 Formal_Type : constant Entity_Id := Etype (Control);
6056 First_Actual : Node_Id;
6059 -- Place the name of the operation, with its interpretations,
6060 -- on the rewritten call.
6062 Set_Name (Call_Node, Subprog);
6064 First_Actual := First (Parameter_Associations (Call_Node));
6066 -- For cross-reference purposes, treat the new node as being in
6067 -- the source if the original one is.
6069 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
6070 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
6072 if Nkind (N) = N_Selected_Component
6073 and then not Inside_A_Generic
6075 Set_Entity (Selector_Name (N), Entity (Subprog));
6078 -- If need be, rewrite first actual as an explicit dereference
6079 -- If the call is overloaded, the rewriting can only be done
6080 -- once the primitive operation is identified.
6082 if Is_Overloaded (Subprog) then
6084 -- The prefix itself may be overloaded, and its interpretations
6085 -- must be propagated to the new actual in the call.
6087 if Is_Overloaded (Obj) then
6088 Save_Interps (Obj, First_Actual);
6091 Rewrite (First_Actual, Obj);
6093 elsif not Is_Access_Type (Formal_Type)
6094 and then Is_Access_Type (Etype (Obj))
6096 Rewrite (First_Actual,
6097 Make_Explicit_Dereference (Sloc (Obj), Obj));
6098 Analyze (First_Actual);
6100 -- If we need to introduce an explicit dereference, verify that
6101 -- the resulting actual is compatible with the mode of the formal.
6103 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
6104 and then Is_Access_Constant (Etype (Obj))
6107 ("expect variable in call to&", Prefix (N), Entity (Subprog));
6110 -- Conversely, if the formal is an access parameter and the object
6111 -- is not, replace the actual with a 'Access reference. Its analysis
6112 -- will check that the object is aliased.
6114 elsif Is_Access_Type (Formal_Type)
6115 and then not Is_Access_Type (Etype (Obj))
6117 -- A special case: A.all'access is illegal if A is an access to a
6118 -- constant and the context requires an access to a variable.
6120 if not Is_Access_Constant (Formal_Type) then
6121 if (Nkind (Obj) = N_Explicit_Dereference
6122 and then Is_Access_Constant (Etype (Prefix (Obj))))
6123 or else not Is_Variable (Obj)
6126 ("actual for& must be a variable", Obj, Control);
6130 Rewrite (First_Actual,
6131 Make_Attribute_Reference (Loc,
6132 Attribute_Name => Name_Access,
6133 Prefix => Relocate_Node (Obj)));
6135 if not Is_Aliased_View (Obj) then
6137 ("object in prefixed call to& must be aliased"
6138 & " (RM-2005 4.3.1 (13))",
6139 Prefix (First_Actual), Subprog);
6142 Analyze (First_Actual);
6145 if Is_Overloaded (Obj) then
6146 Save_Interps (Obj, First_Actual);
6149 Rewrite (First_Actual, Obj);
6152 Rewrite (Node_To_Replace, Call_Node);
6154 -- Propagate the interpretations collected in subprog to the new
6155 -- function call node, to be resolved from context.
6157 if Is_Overloaded (Subprog) then
6158 Save_Interps (Subprog, Node_To_Replace);
6160 Analyze (Node_To_Replace);
6162 end Complete_Object_Operation;
6164 ----------------------
6165 -- Report_Ambiguity --
6166 ----------------------
6168 procedure Report_Ambiguity (Op : Entity_Id) is
6169 Access_Formal : constant Boolean :=
6170 Is_Access_Type (Etype (First_Formal (Op)));
6171 Access_Actual : constant Boolean :=
6172 Is_Access_Type (Etype (Prefix (N)));
6175 Error_Msg_Sloc := Sloc (Op);
6177 if Access_Formal and then not Access_Actual then
6178 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6180 ("\possible interpretation"
6181 & " (inherited, with implicit 'Access) #", N);
6184 ("\possible interpretation (with implicit 'Access) #", N);
6187 elsif not Access_Formal and then Access_Actual then
6188 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6190 ("\possible interpretation"
6191 & " ( inherited, with implicit dereference) #", N);
6194 ("\possible interpretation (with implicit dereference) #", N);
6198 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6199 Error_Msg_N ("\possible interpretation (inherited)#", N);
6201 Error_Msg_N -- CODEFIX
6202 ("\possible interpretation#", N);
6205 end Report_Ambiguity;
6207 --------------------------------
6208 -- Transform_Object_Operation --
6209 --------------------------------
6211 procedure Transform_Object_Operation
6212 (Call_Node : out Node_Id;
6213 Node_To_Replace : out Node_Id)
6215 Dummy : constant Node_Id := New_Copy (Obj);
6216 -- Placeholder used as a first parameter in the call, replaced
6217 -- eventually by the proper object.
6219 Parent_Node : constant Node_Id := Parent (N);
6225 -- Common case covering 1) Call to a procedure and 2) Call to a
6226 -- function that has some additional actuals.
6228 if Nkind_In (Parent_Node, N_Function_Call,
6229 N_Procedure_Call_Statement)
6231 -- N is a selected component node containing the name of the
6232 -- subprogram. If N is not the name of the parent node we must
6233 -- not replace the parent node by the new construct. This case
6234 -- occurs when N is a parameterless call to a subprogram that
6235 -- is an actual parameter of a call to another subprogram. For
6237 -- Some_Subprogram (..., Obj.Operation, ...)
6239 and then Name (Parent_Node) = N
6241 Node_To_Replace := Parent_Node;
6243 Actuals := Parameter_Associations (Parent_Node);
6245 if Present (Actuals) then
6246 Prepend (Dummy, Actuals);
6248 Actuals := New_List (Dummy);
6251 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6253 Make_Procedure_Call_Statement (Loc,
6254 Name => New_Copy (Subprog),
6255 Parameter_Associations => Actuals);
6259 Make_Function_Call (Loc,
6260 Name => New_Copy (Subprog),
6261 Parameter_Associations => Actuals);
6265 -- Before analysis, a function call appears as an indexed component
6266 -- if there are no named associations.
6268 elsif Nkind (Parent_Node) = N_Indexed_Component
6269 and then N = Prefix (Parent_Node)
6271 Node_To_Replace := Parent_Node;
6273 Actuals := Expressions (Parent_Node);
6275 Actual := First (Actuals);
6276 while Present (Actual) loop
6281 Prepend (Dummy, Actuals);
6284 Make_Function_Call (Loc,
6285 Name => New_Copy (Subprog),
6286 Parameter_Associations => Actuals);
6288 -- Parameterless call: Obj.F is rewritten as F (Obj)
6291 Node_To_Replace := N;
6294 Make_Function_Call (Loc,
6295 Name => New_Copy (Subprog),
6296 Parameter_Associations => New_List (Dummy));
6298 end Transform_Object_Operation;
6300 ------------------------------
6301 -- Try_Class_Wide_Operation --
6302 ------------------------------
6304 function Try_Class_Wide_Operation
6305 (Call_Node : Node_Id;
6306 Node_To_Replace : Node_Id) return Boolean
6308 Anc_Type : Entity_Id;
6309 Matching_Op : Entity_Id := Empty;
6312 procedure Traverse_Homonyms
6313 (Anc_Type : Entity_Id;
6314 Error : out Boolean);
6315 -- Traverse the homonym chain of the subprogram searching for those
6316 -- homonyms whose first formal has the Anc_Type's class-wide type,
6317 -- or an anonymous access type designating the class-wide type. If
6318 -- an ambiguity is detected, then Error is set to True.
6320 procedure Traverse_Interfaces
6321 (Anc_Type : Entity_Id;
6322 Error : out Boolean);
6323 -- Traverse the list of interfaces, if any, associated with Anc_Type
6324 -- and search for acceptable class-wide homonyms associated with each
6325 -- interface. If an ambiguity is detected, then Error is set to True.
6327 -----------------------
6328 -- Traverse_Homonyms --
6329 -----------------------
6331 procedure Traverse_Homonyms
6332 (Anc_Type : Entity_Id;
6333 Error : out Boolean)
6335 Cls_Type : Entity_Id;
6343 Cls_Type := Class_Wide_Type (Anc_Type);
6345 Hom := Current_Entity (Subprog);
6347 -- Find operation whose first parameter is of the class-wide
6348 -- type, a subtype thereof, or an anonymous access to same.
6350 while Present (Hom) loop
6351 if (Ekind (Hom) = E_Procedure
6353 Ekind (Hom) = E_Function)
6354 and then Scope (Hom) = Scope (Anc_Type)
6355 and then Present (First_Formal (Hom))
6357 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6359 (Is_Access_Type (Etype (First_Formal (Hom)))
6361 Ekind (Etype (First_Formal (Hom))) =
6362 E_Anonymous_Access_Type
6365 (Designated_Type (Etype (First_Formal (Hom)))) =
6368 Set_Etype (Call_Node, Any_Type);
6369 Set_Is_Overloaded (Call_Node, False);
6372 if No (Matching_Op) then
6373 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6374 Set_Etype (Call_Node, Any_Type);
6375 Set_Parent (Call_Node, Parent (Node_To_Replace));
6377 Set_Name (Call_Node, Hom_Ref);
6382 Report => Report_Error,
6384 Skip_First => True);
6387 Valid_Candidate (Success, Call_Node, Hom);
6393 Report => Report_Error,
6395 Skip_First => True);
6397 if Present (Valid_Candidate (Success, Call_Node, Hom))
6398 and then Nkind (Call_Node) /= N_Function_Call
6400 Error_Msg_NE ("ambiguous call to&", N, Hom);
6401 Report_Ambiguity (Matching_Op);
6402 Report_Ambiguity (Hom);
6409 Hom := Homonym (Hom);
6411 end Traverse_Homonyms;
6413 -------------------------
6414 -- Traverse_Interfaces --
6415 -------------------------
6417 procedure Traverse_Interfaces
6418 (Anc_Type : Entity_Id;
6419 Error : out Boolean)
6421 Intface_List : constant List_Id :=
6422 Abstract_Interface_List (Anc_Type);
6428 if Is_Non_Empty_List (Intface_List) then
6429 Intface := First (Intface_List);
6430 while Present (Intface) loop
6432 -- Look for acceptable class-wide homonyms associated with
6435 Traverse_Homonyms (Etype (Intface), Error);
6441 -- Continue the search by looking at each of the interface's
6442 -- associated interface ancestors.
6444 Traverse_Interfaces (Etype (Intface), Error);
6453 end Traverse_Interfaces;
6455 -- Start of processing for Try_Class_Wide_Operation
6458 -- Loop through ancestor types (including interfaces), traversing
6459 -- the homonym chain of the subprogram, trying out those homonyms
6460 -- whose first formal has the class-wide type of the ancestor, or
6461 -- an anonymous access type designating the class-wide type.
6463 Anc_Type := Obj_Type;
6465 -- Look for a match among homonyms associated with the ancestor
6467 Traverse_Homonyms (Anc_Type, Error);
6473 -- Continue the search for matches among homonyms associated with
6474 -- any interfaces implemented by the ancestor.
6476 Traverse_Interfaces (Anc_Type, Error);
6482 exit when Etype (Anc_Type) = Anc_Type;
6483 Anc_Type := Etype (Anc_Type);
6486 if Present (Matching_Op) then
6487 Set_Etype (Call_Node, Etype (Matching_Op));
6490 return Present (Matching_Op);
6491 end Try_Class_Wide_Operation;
6493 -----------------------------------
6494 -- Try_One_Prefix_Interpretation --
6495 -----------------------------------
6497 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6501 if Is_Access_Type (Obj_Type) then
6502 Obj_Type := Designated_Type (Obj_Type);
6505 if Ekind (Obj_Type) = E_Private_Subtype then
6506 Obj_Type := Base_Type (Obj_Type);
6509 if Is_Class_Wide_Type (Obj_Type) then
6510 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6513 -- The type may have be obtained through a limited_with clause,
6514 -- in which case the primitive operations are available on its
6515 -- non-limited view. If still incomplete, retrieve full view.
6517 if Ekind (Obj_Type) = E_Incomplete_Type
6518 and then From_With_Type (Obj_Type)
6520 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6523 -- If the object is not tagged, or the type is still an incomplete
6524 -- type, this is not a prefixed call.
6526 if not Is_Tagged_Type (Obj_Type)
6527 or else Is_Incomplete_Type (Obj_Type)
6532 if Try_Primitive_Operation
6533 (Call_Node => New_Call_Node,
6534 Node_To_Replace => Node_To_Replace)
6536 Try_Class_Wide_Operation
6537 (Call_Node => New_Call_Node,
6538 Node_To_Replace => Node_To_Replace)
6542 end Try_One_Prefix_Interpretation;
6544 -----------------------------
6545 -- Try_Primitive_Operation --
6546 -----------------------------
6548 function Try_Primitive_Operation
6549 (Call_Node : Node_Id;
6550 Node_To_Replace : Node_Id) return Boolean
6553 Prim_Op : Entity_Id;
6554 Matching_Op : Entity_Id := Empty;
6555 Prim_Op_Ref : Node_Id := Empty;
6557 Corr_Type : Entity_Id := Empty;
6558 -- If the prefix is a synchronized type, the controlling type of
6559 -- the primitive operation is the corresponding record type, else
6560 -- this is the object type itself.
6562 Success : Boolean := False;
6564 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
6565 -- For tagged types the candidate interpretations are found in
6566 -- the list of primitive operations of the type and its ancestors.
6567 -- For formal tagged types we have to find the operations declared
6568 -- in the same scope as the type (including in the generic formal
6569 -- part) because the type itself carries no primitive operations,
6570 -- except for formal derived types that inherit the operations of
6571 -- the parent and progenitors.
6572 -- If the context is a generic subprogram body, the generic formals
6573 -- are visible by name, but are not in the entity list of the
6574 -- subprogram because that list starts with the subprogram formals.
6575 -- We retrieve the candidate operations from the generic declaration.
6577 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
6578 -- Verify that the prefix, dereferenced if need be, is a valid
6579 -- controlling argument in a call to Op. The remaining actuals
6580 -- are checked in the subsequent call to Analyze_One_Call.
6582 ------------------------------
6583 -- Collect_Generic_Type_Ops --
6584 ------------------------------
6586 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
6587 Bas : constant Entity_Id := Base_Type (T);
6588 Candidates : constant Elist_Id := New_Elmt_List;
6592 procedure Check_Candidate;
6593 -- The operation is a candidate if its first parameter is a
6594 -- controlling operand of the desired type.
6596 -----------------------
6597 -- Check_Candidate; --
6598 -----------------------
6600 procedure Check_Candidate is
6602 Formal := First_Formal (Subp);
6605 and then Is_Controlling_Formal (Formal)
6607 (Base_Type (Etype (Formal)) = Bas
6609 (Is_Access_Type (Etype (Formal))
6610 and then Designated_Type (Etype (Formal)) = Bas))
6612 Append_Elmt (Subp, Candidates);
6614 end Check_Candidate;
6616 -- Start of processing for Collect_Generic_Type_Ops
6619 if Is_Derived_Type (T) then
6620 return Primitive_Operations (T);
6622 elsif Ekind (Scope (T)) = E_Procedure
6623 or else Ekind (Scope (T)) = E_Function
6625 -- Scan the list of generic formals to find subprograms
6626 -- that may have a first controlling formal of the type.
6633 First (Generic_Formal_Declarations
6634 (Unit_Declaration_Node (Scope (T))));
6635 while Present (Decl) loop
6636 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
6637 Subp := Defining_Entity (Decl);
6648 -- Scan the list of entities declared in the same scope as
6649 -- the type. In general this will be an open scope, given that
6650 -- the call we are analyzing can only appear within a generic
6651 -- declaration or body (either the one that declares T, or a
6654 Subp := First_Entity (Scope (T));
6655 while Present (Subp) loop
6656 if Is_Overloadable (Subp) then
6665 end Collect_Generic_Type_Ops;
6667 -----------------------------
6668 -- Valid_First_Argument_Of --
6669 -----------------------------
6671 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
6672 Typ : Entity_Id := Etype (First_Formal (Op));
6675 if Is_Concurrent_Type (Typ)
6676 and then Present (Corresponding_Record_Type (Typ))
6678 Typ := Corresponding_Record_Type (Typ);
6681 -- Simple case. Object may be a subtype of the tagged type or
6682 -- may be the corresponding record of a synchronized type.
6684 return Obj_Type = Typ
6685 or else Base_Type (Obj_Type) = Typ
6686 or else Corr_Type = Typ
6688 -- Prefix can be dereferenced
6691 (Is_Access_Type (Corr_Type)
6692 and then Designated_Type (Corr_Type) = Typ)
6694 -- Formal is an access parameter, for which the object
6695 -- can provide an access.
6698 (Ekind (Typ) = E_Anonymous_Access_Type
6699 and then Designated_Type (Typ) = Base_Type (Corr_Type));
6700 end Valid_First_Argument_Of;
6702 -- Start of processing for Try_Primitive_Operation
6705 -- Look for subprograms in the list of primitive operations. The name
6706 -- must be identical, and the kind of call indicates the expected
6707 -- kind of operation (function or procedure). If the type is a
6708 -- (tagged) synchronized type, the primitive ops are attached to the
6709 -- corresponding record (base) type.
6711 if Is_Concurrent_Type (Obj_Type) then
6712 if not Present (Corresponding_Record_Type (Obj_Type)) then
6716 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
6717 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
6719 elsif not Is_Generic_Type (Obj_Type) then
6720 Corr_Type := Obj_Type;
6721 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
6724 Corr_Type := Obj_Type;
6725 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
6728 while Present (Elmt) loop
6729 Prim_Op := Node (Elmt);
6731 if Chars (Prim_Op) = Chars (Subprog)
6732 and then Present (First_Formal (Prim_Op))
6733 and then Valid_First_Argument_Of (Prim_Op)
6735 (Nkind (Call_Node) = N_Function_Call)
6736 = (Ekind (Prim_Op) = E_Function)
6738 -- Ada 2005 (AI-251): If this primitive operation corresponds
6739 -- with an immediate ancestor interface there is no need to add
6740 -- it to the list of interpretations; the corresponding aliased
6741 -- primitive is also in this list of primitive operations and
6742 -- will be used instead.
6744 if (Present (Interface_Alias (Prim_Op))
6745 and then Is_Ancestor (Find_Dispatching_Type
6746 (Alias (Prim_Op)), Corr_Type))
6749 -- Do not consider hidden primitives unless the type is
6750 -- in an open scope or we are within an instance, where
6751 -- visibility is known to be correct.
6753 (Is_Hidden (Prim_Op)
6754 and then not Is_Immediately_Visible (Obj_Type)
6755 and then not In_Instance)
6760 Set_Etype (Call_Node, Any_Type);
6761 Set_Is_Overloaded (Call_Node, False);
6763 if No (Matching_Op) then
6764 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
6765 Candidate := Prim_Op;
6767 Set_Parent (Call_Node, Parent (Node_To_Replace));
6769 Set_Name (Call_Node, Prim_Op_Ref);
6775 Report => Report_Error,
6777 Skip_First => True);
6779 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
6781 -- More than one interpretation, collect for subsequent
6782 -- disambiguation. If this is a procedure call and there
6783 -- is another match, report ambiguity now.
6789 Report => Report_Error,
6791 Skip_First => True);
6793 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
6794 and then Nkind (Call_Node) /= N_Function_Call
6796 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
6797 Report_Ambiguity (Matching_Op);
6798 Report_Ambiguity (Prim_Op);
6808 if Present (Matching_Op) then
6809 Set_Etype (Call_Node, Etype (Matching_Op));
6812 return Present (Matching_Op);
6813 end Try_Primitive_Operation;
6815 -- Start of processing for Try_Object_Operation
6818 Analyze_Expression (Obj);
6820 -- Analyze the actuals if node is known to be a subprogram call
6822 if Is_Subprg_Call and then N = Name (Parent (N)) then
6823 Actual := First (Parameter_Associations (Parent (N)));
6824 while Present (Actual) loop
6825 Analyze_Expression (Actual);
6830 -- Build a subprogram call node, using a copy of Obj as its first
6831 -- actual. This is a placeholder, to be replaced by an explicit
6832 -- dereference when needed.
6834 Transform_Object_Operation
6835 (Call_Node => New_Call_Node,
6836 Node_To_Replace => Node_To_Replace);
6838 Set_Etype (New_Call_Node, Any_Type);
6839 Set_Etype (Subprog, Any_Type);
6840 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
6842 if not Is_Overloaded (Obj) then
6843 Try_One_Prefix_Interpretation (Obj_Type);
6850 Get_First_Interp (Obj, I, It);
6851 while Present (It.Nam) loop
6852 Try_One_Prefix_Interpretation (It.Typ);
6853 Get_Next_Interp (I, It);
6858 if Etype (New_Call_Node) /= Any_Type then
6859 Complete_Object_Operation
6860 (Call_Node => New_Call_Node,
6861 Node_To_Replace => Node_To_Replace);
6864 elsif Present (Candidate) then
6866 -- The argument list is not type correct. Re-analyze with error
6867 -- reporting enabled, and use one of the possible candidates.
6868 -- In All_Errors_Mode, re-analyze all failed interpretations.
6870 if All_Errors_Mode then
6871 Report_Error := True;
6872 if Try_Primitive_Operation
6873 (Call_Node => New_Call_Node,
6874 Node_To_Replace => Node_To_Replace)
6877 Try_Class_Wide_Operation
6878 (Call_Node => New_Call_Node,
6879 Node_To_Replace => Node_To_Replace)
6886 (N => New_Call_Node,
6890 Skip_First => True);
6893 -- No need for further errors
6898 -- There was no candidate operation, so report it as an error
6899 -- in the caller: Analyze_Selected_Component.
6903 end Try_Object_Operation;
6909 procedure wpo (T : Entity_Id) is
6914 if not Is_Tagged_Type (T) then
6918 E := First_Elmt (Primitive_Operations (Base_Type (T)));
6919 while Present (E) loop
6921 Write_Int (Int (Op));
6922 Write_Str (" === ");
6923 Write_Name (Chars (Op));
6925 Write_Name (Chars (Scope (Op)));