1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Debug; use Debug;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_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
131 -- a misspelling of one of the selectors of the Prefix.
132 -- This is called by Analyze_Selected_Component after producing
133 -- an invalid selector error message.
135 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean;
136 -- Verify that type T is declared in scope S. Used to find interpretations
137 -- for operators given by expanded names. This is abstracted as a separate
138 -- function to handle extensions to System, where S is System, but T is
139 -- declared in the extension.
141 procedure Find_Arithmetic_Types
145 -- L and R are the operands of an arithmetic operator. Find
146 -- consistent pairs of interpretations for L and R that have a
147 -- numeric type consistent with the semantics of the operator.
149 procedure Find_Comparison_Types
153 -- L and R are operands of a comparison operator. Find consistent
154 -- pairs of interpretations for L and R.
156 procedure Find_Concatenation_Types
160 -- For the four varieties of concatenation
162 procedure Find_Equality_Types
166 -- Ditto for equality operators
168 procedure Find_Boolean_Types
172 -- Ditto for binary logical operations
174 procedure Find_Negation_Types
178 -- Find consistent interpretation for operand of negation operator
180 procedure Find_Non_Universal_Interpretations
185 -- For equality and comparison operators, the result is always boolean,
186 -- and the legality of the operation is determined from the visibility
187 -- of the operand types. If one of the operands has a universal interpre-
188 -- tation, the legality check uses some compatible non-universal
189 -- interpretation of the other operand. N can be an operator node, or
190 -- a function call whose name is an operator designator.
192 function Find_Primitive_Operation (N : Node_Id) return Boolean;
193 -- Find candidate interpretations for the name Obj.Proc when it appears
194 -- in a subprogram renaming declaration.
196 procedure Find_Unary_Types
200 -- Unary arithmetic types: plus, minus, abs
202 procedure Check_Arithmetic_Pair
206 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid
207 -- types for left and right operand. Determine whether they constitute
208 -- a valid pair for the given operator, and record the corresponding
209 -- interpretation of the operator node. The node N may be an operator
210 -- node (the usual case) or a function call whose prefix is an operator
211 -- designator. In both cases Op_Id is the operator name itself.
213 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id);
214 -- Give detailed information on overloaded call where none of the
215 -- interpretations match. N is the call node, Nam the designator for
216 -- the overloaded entity being called.
218 function Junk_Operand (N : Node_Id) return Boolean;
219 -- Test for an operand that is an inappropriate entity (e.g. a package
220 -- name or a label). If so, issue an error message and return True. If
221 -- the operand is not an inappropriate entity kind, return False.
223 procedure Operator_Check (N : Node_Id);
224 -- Verify that an operator has received some valid interpretation. If none
225 -- was found, determine whether a use clause would make the operation
226 -- legal. The variable Candidate_Type (defined in Sem_Type) is set for
227 -- every type compatible with the operator, even if the operator for the
228 -- type is not directly visible. The routine uses this type to emit a more
229 -- informative message.
231 function Process_Implicit_Dereference_Prefix
233 P : Node_Id) return Entity_Id;
234 -- Called when P is the prefix of an implicit dereference, denoting an
235 -- object E. The function returns the designated type of the prefix, taking
236 -- into account that the designated type of an anonymous access type may be
237 -- a limited view, when the non-limited view is visible.
238 -- If in semantics only mode (-gnatc or generic), the function also records
239 -- that the prefix is a reference to E, if any. Normally, such a reference
240 -- is generated only when the implicit dereference is expanded into an
241 -- explicit one, but for consistency we must generate the reference when
242 -- expansion is disabled as well.
244 procedure Remove_Abstract_Operations (N : Node_Id);
245 -- Ada 2005: implementation of AI-310. An abstract non-dispatching
246 -- operation is not a candidate interpretation.
248 function Try_Indexed_Call
252 Skip_First : Boolean) return Boolean;
253 -- If a function has defaults for all its actuals, a call to it may in fact
254 -- be an indexing on the result of the call. Try_Indexed_Call attempts the
255 -- interpretation as an indexing, prior to analysis as a call. If both are
256 -- possible, the node is overloaded with both interpretations (same symbol
257 -- but two different types). If the call is written in prefix form, the
258 -- prefix becomes the first parameter in the call, and only the remaining
259 -- actuals must be checked for the presence of defaults.
261 function Try_Indirect_Call
264 Typ : Entity_Id) return Boolean;
265 -- Similarly, a function F that needs no actuals can return an access to a
266 -- subprogram, and the call F (X) interpreted as F.all (X). In this case
267 -- the call may be overloaded with both interpretations.
269 function Try_Object_Operation (N : Node_Id) return Boolean;
270 -- Ada 2005 (AI-252): Support the object.operation notation
272 procedure wpo (T : Entity_Id);
273 pragma Warnings (Off, wpo);
274 -- Used for debugging: obtain list of primitive operations even if
275 -- type is not frozen and dispatch table is not built yet.
277 ------------------------
278 -- Ambiguous_Operands --
279 ------------------------
281 procedure Ambiguous_Operands (N : Node_Id) is
282 procedure List_Operand_Interps (Opnd : Node_Id);
284 --------------------------
285 -- List_Operand_Interps --
286 --------------------------
288 procedure List_Operand_Interps (Opnd : Node_Id) is
293 if Is_Overloaded (Opnd) then
294 if Nkind (Opnd) in N_Op then
296 elsif Nkind (Opnd) = N_Function_Call then
306 if Opnd = Left_Opnd (N) then
308 ("\left operand has the following interpretations", N);
311 ("\right operand has the following interpretations", N);
315 List_Interps (Nam, Err);
316 end List_Operand_Interps;
318 -- Start of processing for Ambiguous_Operands
321 if Nkind (N) in N_Membership_Test then
322 Error_Msg_N ("ambiguous operands for membership", N);
324 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne) then
325 Error_Msg_N ("ambiguous operands for equality", N);
328 Error_Msg_N ("ambiguous operands for comparison", N);
331 if All_Errors_Mode then
332 List_Operand_Interps (Left_Opnd (N));
333 List_Operand_Interps (Right_Opnd (N));
335 Error_Msg_N ("\use -gnatf switch for details", N);
337 end Ambiguous_Operands;
339 -----------------------
340 -- Analyze_Aggregate --
341 -----------------------
343 -- Most of the analysis of Aggregates requires that the type be known,
344 -- and is therefore put off until resolution.
346 procedure Analyze_Aggregate (N : Node_Id) is
348 if No (Etype (N)) then
349 Set_Etype (N, Any_Composite);
351 end Analyze_Aggregate;
353 -----------------------
354 -- Analyze_Allocator --
355 -----------------------
357 procedure Analyze_Allocator (N : Node_Id) is
358 Loc : constant Source_Ptr := Sloc (N);
359 Sav_Errs : constant Nat := Serious_Errors_Detected;
360 E : Node_Id := Expression (N);
361 Acc_Type : Entity_Id;
365 -- In accordance with H.4(7), the No_Allocators restriction only applies
366 -- to user-written allocators.
368 if Comes_From_Source (N) then
369 Check_Restriction (No_Allocators, N);
372 if Nkind (E) = N_Qualified_Expression then
373 Acc_Type := Create_Itype (E_Allocator_Type, N);
374 Set_Etype (Acc_Type, Acc_Type);
375 Find_Type (Subtype_Mark (E));
377 -- Analyze the qualified expression, and apply the name resolution
378 -- rule given in 4.7 (3).
381 Type_Id := Etype (E);
382 Set_Directly_Designated_Type (Acc_Type, Type_Id);
384 Resolve (Expression (E), Type_Id);
386 if Is_Limited_Type (Type_Id)
387 and then Comes_From_Source (N)
388 and then not In_Instance_Body
390 if not OK_For_Limited_Init (Expression (E)) then
391 Error_Msg_N ("initialization not allowed for limited types", N);
392 Explain_Limited_Type (Type_Id, N);
396 -- A qualified expression requires an exact match of the type,
397 -- class-wide matching is not allowed.
399 -- if Is_Class_Wide_Type (Type_Id)
400 -- and then Base_Type
401 -- (Etype (Expression (E))) /= Base_Type (Type_Id)
403 -- Wrong_Type (Expression (E), Type_Id);
406 Check_Non_Static_Context (Expression (E));
408 -- We don't analyze the qualified expression itself because it's
409 -- part of the allocator
411 Set_Etype (E, Type_Id);
413 -- Case where allocator has a subtype indication
418 Base_Typ : Entity_Id;
421 -- If the allocator includes a N_Subtype_Indication then a
422 -- constraint is present, otherwise the node is a subtype mark.
423 -- Introduce an explicit subtype declaration into the tree
424 -- defining some anonymous subtype and rewrite the allocator to
425 -- use this subtype rather than the subtype indication.
427 -- It is important to introduce the explicit subtype declaration
428 -- so that the bounds of the subtype indication are attached to
429 -- the tree in case the allocator is inside a generic unit.
431 if Nkind (E) = N_Subtype_Indication then
433 -- A constraint is only allowed for a composite type in Ada
434 -- 95. In Ada 83, a constraint is also allowed for an
435 -- access-to-composite type, but the constraint is ignored.
437 Find_Type (Subtype_Mark (E));
438 Base_Typ := Entity (Subtype_Mark (E));
440 if Is_Elementary_Type (Base_Typ) then
441 if not (Ada_Version = Ada_83
442 and then Is_Access_Type (Base_Typ))
444 Error_Msg_N ("constraint not allowed here", E);
446 if Nkind (Constraint (E)) =
447 N_Index_Or_Discriminant_Constraint
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
487 ("if qualified expression was meant, " &
488 "use apostrophe!", Constraint (E));
491 E := New_Occurrence_Of (Def_Id, Loc);
492 Rewrite (Expression (N), E);
496 Type_Id := Process_Subtype (E, N);
497 Acc_Type := Create_Itype (E_Allocator_Type, N);
498 Set_Etype (Acc_Type, Acc_Type);
499 Set_Directly_Designated_Type (Acc_Type, Type_Id);
500 Check_Fully_Declared (Type_Id, N);
502 -- Ada 2005 (AI-231): If the designated type is itself an access
503 -- type that excludes null, its default initialization will
504 -- be a null object, and we can insert an unconditional raise
505 -- before the allocator.
507 if Can_Never_Be_Null (Type_Id) then
509 Not_Null_Check : constant Node_Id :=
510 Make_Raise_Constraint_Error (Sloc (E),
511 Reason => CE_Null_Not_Allowed);
513 if Expander_Active then
514 Insert_Action (N, Not_Null_Check);
515 Analyze (Not_Null_Check);
517 Error_Msg_N ("null value not allowed here?", E);
522 -- Check restriction against dynamically allocated protected
523 -- objects. Note that when limited aggregates are supported,
524 -- a similar test should be applied to an allocator with a
525 -- qualified expression ???
527 if Is_Protected_Type (Type_Id) then
528 Check_Restriction (No_Protected_Type_Allocators, N);
531 -- Check for missing initialization. Skip this check if we already
532 -- had errors on analyzing the allocator, since in that case these
533 -- are probably cascaded errors.
535 if Is_Indefinite_Subtype (Type_Id)
536 and then Serious_Errors_Detected = Sav_Errs
538 if Is_Class_Wide_Type (Type_Id) then
540 ("initialization required in class-wide allocation", N);
542 if Ada_Version < Ada_05
543 and then Is_Limited_Type (Type_Id)
545 Error_Msg_N ("unconstrained allocation not allowed", N);
547 if Is_Array_Type (Type_Id) then
549 ("\constraint with array bounds required", N);
551 elsif Has_Unknown_Discriminants (Type_Id) then
554 else pragma Assert (Has_Discriminants (Type_Id));
556 ("\constraint with discriminant values required", N);
559 -- Limited Ada 2005 and general non-limited case
563 ("uninitialized unconstrained allocation not allowed",
566 if Is_Array_Type (Type_Id) then
568 ("\qualified expression or constraint with " &
569 "array bounds required", N);
571 elsif Has_Unknown_Discriminants (Type_Id) then
572 Error_Msg_N ("\qualified expression required", N);
574 else pragma Assert (Has_Discriminants (Type_Id));
576 ("\qualified expression or constraint with " &
577 "discriminant values required", N);
585 if Is_Abstract_Type (Type_Id) then
586 Error_Msg_N ("cannot allocate abstract object", E);
589 if Has_Task (Designated_Type (Acc_Type)) then
590 Check_Restriction (No_Tasking, N);
591 Check_Restriction (Max_Tasks, N);
592 Check_Restriction (No_Task_Allocators, N);
595 -- If the No_Streams restriction is set, check that the type of the
596 -- object is not, and does not contain, any subtype derived from
597 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
598 -- Has_Stream just for efficiency reasons. There is no point in
599 -- spending time on a Has_Stream check if the restriction is not set.
601 if Restrictions.Set (No_Streams) then
602 if Has_Stream (Designated_Type (Acc_Type)) then
603 Check_Restriction (No_Streams, N);
607 Set_Etype (N, Acc_Type);
609 if not Is_Library_Level_Entity (Acc_Type) then
610 Check_Restriction (No_Local_Allocators, N);
613 if Serious_Errors_Detected > Sav_Errs then
614 Set_Error_Posted (N);
615 Set_Etype (N, Any_Type);
617 end Analyze_Allocator;
619 ---------------------------
620 -- Analyze_Arithmetic_Op --
621 ---------------------------
623 procedure Analyze_Arithmetic_Op (N : Node_Id) is
624 L : constant Node_Id := Left_Opnd (N);
625 R : constant Node_Id := Right_Opnd (N);
629 Candidate_Type := Empty;
630 Analyze_Expression (L);
631 Analyze_Expression (R);
633 -- If the entity is already set, the node is the instantiation of a
634 -- generic node with a non-local reference, or was manufactured by a
635 -- call to Make_Op_xxx. In either case the entity is known to be valid,
636 -- and we do not need to collect interpretations, instead we just get
637 -- the single possible interpretation.
641 if Present (Op_Id) then
642 if Ekind (Op_Id) = E_Operator then
644 if Nkind_In (N, N_Op_Divide, N_Op_Mod, N_Op_Multiply, N_Op_Rem)
645 and then Treat_Fixed_As_Integer (N)
649 Set_Etype (N, Any_Type);
650 Find_Arithmetic_Types (L, R, Op_Id, N);
654 Set_Etype (N, Any_Type);
655 Add_One_Interp (N, Op_Id, Etype (Op_Id));
658 -- Entity is not already set, so we do need to collect interpretations
661 Op_Id := Get_Name_Entity_Id (Chars (N));
662 Set_Etype (N, Any_Type);
664 while Present (Op_Id) loop
665 if Ekind (Op_Id) = E_Operator
666 and then Present (Next_Entity (First_Entity (Op_Id)))
668 Find_Arithmetic_Types (L, R, Op_Id, N);
670 -- The following may seem superfluous, because an operator cannot
671 -- be generic, but this ignores the cleverness of the author of
674 elsif Is_Overloadable (Op_Id) then
675 Analyze_User_Defined_Binary_Op (N, Op_Id);
678 Op_Id := Homonym (Op_Id);
683 end Analyze_Arithmetic_Op;
689 -- Function, procedure, and entry calls are checked here. The Name in
690 -- the call may be overloaded. The actuals have been analyzed and may
691 -- themselves be overloaded. On exit from this procedure, the node N
692 -- may have zero, one or more interpretations. In the first case an
693 -- error message is produced. In the last case, the node is flagged
694 -- as overloaded and the interpretations are collected in All_Interp.
696 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
697 -- the type-checking is similar to that of other calls.
699 procedure Analyze_Call (N : Node_Id) is
700 Actuals : constant List_Id := Parameter_Associations (N);
705 Success : Boolean := False;
707 Deref : Boolean := False;
708 -- Flag indicates whether an interpretation of the prefix is a
709 -- parameterless call that returns an access_to_subprogram.
711 function Name_Denotes_Function return Boolean;
712 -- If the type of the name is an access to subprogram, this may be the
713 -- type of a name, or the return type of the function being called. If
714 -- the name is not an entity then it can denote a protected function.
715 -- Until we distinguish Etype from Return_Type, we must use this routine
716 -- to resolve the meaning of the name in the call.
718 procedure No_Interpretation;
719 -- Output error message when no valid interpretation exists
721 ---------------------------
722 -- Name_Denotes_Function --
723 ---------------------------
725 function Name_Denotes_Function return Boolean is
727 if Is_Entity_Name (Nam) then
728 return Ekind (Entity (Nam)) = E_Function;
730 elsif Nkind (Nam) = N_Selected_Component then
731 return Ekind (Entity (Selector_Name (Nam))) = E_Function;
736 end Name_Denotes_Function;
738 -----------------------
739 -- No_Interpretation --
740 -----------------------
742 procedure No_Interpretation is
743 L : constant Boolean := Is_List_Member (N);
744 K : constant Node_Kind := Nkind (Parent (N));
747 -- If the node is in a list whose parent is not an expression then it
748 -- must be an attempted procedure call.
750 if L and then K not in N_Subexpr then
751 if Ekind (Entity (Nam)) = E_Generic_Procedure then
753 ("must instantiate generic procedure& before call",
757 ("procedure or entry name expected", Nam);
760 -- Check for tasking cases where only an entry call will do
763 and then Nkind_In (K, N_Entry_Call_Alternative,
764 N_Triggering_Alternative)
766 Error_Msg_N ("entry name expected", Nam);
768 -- Otherwise give general error message
771 Error_Msg_N ("invalid prefix in call", Nam);
773 end No_Interpretation;
775 -- Start of processing for Analyze_Call
778 -- Initialize the type of the result of the call to the error type,
779 -- which will be reset if the type is successfully resolved.
781 Set_Etype (N, Any_Type);
785 if not Is_Overloaded (Nam) then
787 -- Only one interpretation to check
789 if Ekind (Etype (Nam)) = E_Subprogram_Type then
790 Nam_Ent := Etype (Nam);
792 -- If the prefix is an access_to_subprogram, this may be an indirect
793 -- call. This is the case if the name in the call is not an entity
794 -- name, or if it is a function name in the context of a procedure
795 -- call. In this latter case, we have a call to a parameterless
796 -- function that returns a pointer_to_procedure which is the entity
797 -- being called. Finally, F (X) may be a call to a parameterless
798 -- function that returns a pointer to a function with parameters.
800 elsif Is_Access_Type (Etype (Nam))
801 and then Ekind (Designated_Type (Etype (Nam))) = E_Subprogram_Type
803 (not Name_Denotes_Function
804 or else Nkind (N) = N_Procedure_Call_Statement
806 (Nkind (Parent (N)) /= N_Explicit_Dereference
807 and then Is_Entity_Name (Nam)
808 and then No (First_Formal (Entity (Nam)))
809 and then Present (Actuals)))
811 Nam_Ent := Designated_Type (Etype (Nam));
812 Insert_Explicit_Dereference (Nam);
814 -- Selected component case. Simple entry or protected operation,
815 -- where the entry name is given by the selector name.
817 elsif Nkind (Nam) = N_Selected_Component then
818 Nam_Ent := Entity (Selector_Name (Nam));
820 if Ekind (Nam_Ent) /= E_Entry
821 and then Ekind (Nam_Ent) /= E_Entry_Family
822 and then Ekind (Nam_Ent) /= E_Function
823 and then Ekind (Nam_Ent) /= E_Procedure
825 Error_Msg_N ("name in call is not a callable entity", Nam);
826 Set_Etype (N, Any_Type);
830 -- If the name is an Indexed component, it can be a call to a member
831 -- of an entry family. The prefix must be a selected component whose
832 -- selector is the entry. Analyze_Procedure_Call normalizes several
833 -- kinds of call into this form.
835 elsif Nkind (Nam) = N_Indexed_Component then
836 if Nkind (Prefix (Nam)) = N_Selected_Component then
837 Nam_Ent := Entity (Selector_Name (Prefix (Nam)));
839 Error_Msg_N ("name in call is not a callable entity", Nam);
840 Set_Etype (N, Any_Type);
844 elsif not Is_Entity_Name (Nam) then
845 Error_Msg_N ("name in call is not a callable entity", Nam);
846 Set_Etype (N, Any_Type);
850 Nam_Ent := Entity (Nam);
852 -- If no interpretations, give error message
854 if not Is_Overloadable (Nam_Ent) then
860 -- Operations generated for RACW stub types are called only through
861 -- dispatching, and can never be the static interpretation of a call.
863 if Is_RACW_Stub_Type_Operation (Nam_Ent) then
868 Analyze_One_Call (N, Nam_Ent, True, Success);
870 -- If this is an indirect call, the return type of the access_to
871 -- subprogram may be an incomplete type. At the point of the call,
872 -- use the full type if available, and at the same time update
873 -- the return type of the access_to_subprogram.
876 and then Nkind (Nam) = N_Explicit_Dereference
877 and then Ekind (Etype (N)) = E_Incomplete_Type
878 and then Present (Full_View (Etype (N)))
880 Set_Etype (N, Full_View (Etype (N)));
881 Set_Etype (Nam_Ent, Etype (N));
885 -- An overloaded selected component must denote overloaded operations
886 -- of a concurrent type. The interpretations are attached to the
887 -- simple name of those operations.
889 if Nkind (Nam) = N_Selected_Component then
890 Nam := Selector_Name (Nam);
893 Get_First_Interp (Nam, X, It);
895 while Present (It.Nam) loop
899 -- Name may be call that returns an access to subprogram, or more
900 -- generally an overloaded expression one of whose interpretations
901 -- yields an access to subprogram. If the name is an entity, we
902 -- do not dereference, because the node is a call that returns
903 -- the access type: note difference between f(x), where the call
904 -- may return an access subprogram type, and f(x)(y), where the
905 -- type returned by the call to f is implicitly dereferenced to
906 -- analyze the outer call.
908 if Is_Access_Type (Nam_Ent) then
909 Nam_Ent := Designated_Type (Nam_Ent);
911 elsif Is_Access_Type (Etype (Nam_Ent))
913 (not Is_Entity_Name (Nam)
914 or else Nkind (N) = N_Procedure_Call_Statement)
915 and then Ekind (Designated_Type (Etype (Nam_Ent)))
918 Nam_Ent := Designated_Type (Etype (Nam_Ent));
920 if Is_Entity_Name (Nam) then
925 Analyze_One_Call (N, Nam_Ent, False, Success);
927 -- If the interpretation succeeds, mark the proper type of the
928 -- prefix (any valid candidate will do). If not, remove the
929 -- candidate interpretation. This only needs to be done for
930 -- overloaded protected operations, for other entities disambi-
931 -- guation is done directly in Resolve.
935 and then Nkind (Parent (N)) /= N_Explicit_Dereference
937 Set_Entity (Nam, It.Nam);
938 Insert_Explicit_Dereference (Nam);
939 Set_Etype (Nam, Nam_Ent);
942 Set_Etype (Nam, It.Typ);
945 elsif Nkind_In (Name (N), N_Selected_Component,
951 Get_Next_Interp (X, It);
954 -- If the name is the result of a function call, it can only
955 -- be a call to a function returning an access to subprogram.
956 -- Insert explicit dereference.
958 if Nkind (Nam) = N_Function_Call then
959 Insert_Explicit_Dereference (Nam);
962 if Etype (N) = Any_Type then
964 -- None of the interpretations is compatible with the actuals
966 Diagnose_Call (N, Nam);
968 -- Special checks for uninstantiated put routines
970 if Nkind (N) = N_Procedure_Call_Statement
971 and then Is_Entity_Name (Nam)
972 and then Chars (Nam) = Name_Put
973 and then List_Length (Actuals) = 1
976 Arg : constant Node_Id := First (Actuals);
980 if Nkind (Arg) = N_Parameter_Association then
981 Typ := Etype (Explicit_Actual_Parameter (Arg));
986 if Is_Signed_Integer_Type (Typ) then
988 ("possible missing instantiation of " &
989 "'Text_'I'O.'Integer_'I'O!", Nam);
991 elsif Is_Modular_Integer_Type (Typ) then
993 ("possible missing instantiation of " &
994 "'Text_'I'O.'Modular_'I'O!", Nam);
996 elsif Is_Floating_Point_Type (Typ) then
998 ("possible missing instantiation of " &
999 "'Text_'I'O.'Float_'I'O!", Nam);
1001 elsif Is_Ordinary_Fixed_Point_Type (Typ) then
1003 ("possible missing instantiation of " &
1004 "'Text_'I'O.'Fixed_'I'O!", Nam);
1006 elsif Is_Decimal_Fixed_Point_Type (Typ) then
1008 ("possible missing instantiation of " &
1009 "'Text_'I'O.'Decimal_'I'O!", Nam);
1011 elsif Is_Enumeration_Type (Typ) then
1013 ("possible missing instantiation of " &
1014 "'Text_'I'O.'Enumeration_'I'O!", Nam);
1019 elsif not Is_Overloaded (N)
1020 and then Is_Entity_Name (Nam)
1022 -- Resolution yields a single interpretation. Verify that the
1023 -- reference has capitalization consistent with the declaration.
1025 Set_Entity_With_Style_Check (Nam, Entity (Nam));
1026 Generate_Reference (Entity (Nam), Nam);
1028 Set_Etype (Nam, Etype (Entity (Nam)));
1030 Remove_Abstract_Operations (N);
1037 ---------------------------
1038 -- Analyze_Comparison_Op --
1039 ---------------------------
1041 procedure Analyze_Comparison_Op (N : Node_Id) is
1042 L : constant Node_Id := Left_Opnd (N);
1043 R : constant Node_Id := Right_Opnd (N);
1044 Op_Id : Entity_Id := Entity (N);
1047 Set_Etype (N, Any_Type);
1048 Candidate_Type := Empty;
1050 Analyze_Expression (L);
1051 Analyze_Expression (R);
1053 if Present (Op_Id) then
1054 if Ekind (Op_Id) = E_Operator then
1055 Find_Comparison_Types (L, R, Op_Id, N);
1057 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1060 if Is_Overloaded (L) then
1061 Set_Etype (L, Intersect_Types (L, R));
1065 Op_Id := Get_Name_Entity_Id (Chars (N));
1066 while Present (Op_Id) loop
1067 if Ekind (Op_Id) = E_Operator then
1068 Find_Comparison_Types (L, R, Op_Id, N);
1070 Analyze_User_Defined_Binary_Op (N, Op_Id);
1073 Op_Id := Homonym (Op_Id);
1078 end Analyze_Comparison_Op;
1080 ---------------------------
1081 -- Analyze_Concatenation --
1082 ---------------------------
1084 procedure Analyze_Concatenation (N : Node_Id) is
1086 -- We wish to avoid deep recursion, because concatenations are often
1087 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1088 -- operands nonrecursively until we find something that is not a
1089 -- concatenation (A in this case), or has already been analyzed. We
1090 -- analyze that, and then walk back up the tree following Parent
1091 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1092 -- work at each level. The Parent pointers allow us to avoid recursion,
1093 -- and thus avoid running out of memory.
1099 Candidate_Type := Empty;
1101 -- The following code is equivalent to:
1103 -- Set_Etype (N, Any_Type);
1104 -- Analyze_Expression (Left_Opnd (N));
1105 -- Analyze_Concatenation_Rest (N);
1107 -- where the Analyze_Expression call recurses back here if the left
1108 -- operand is a concatenation.
1110 -- Walk down left operands
1113 Set_Etype (NN, Any_Type);
1114 L := Left_Opnd (NN);
1115 exit when Nkind (L) /= N_Op_Concat or else Analyzed (L);
1119 -- Now (given the above example) NN is A&B and L is A
1121 -- First analyze L ...
1123 Analyze_Expression (L);
1125 -- ... then walk NN back up until we reach N (where we started), calling
1126 -- Analyze_Concatenation_Rest along the way.
1129 Analyze_Concatenation_Rest (NN);
1133 end Analyze_Concatenation;
1135 --------------------------------
1136 -- Analyze_Concatenation_Rest --
1137 --------------------------------
1139 -- If the only one-dimensional array type in scope is String,
1140 -- this is the resulting type of the operation. Otherwise there
1141 -- will be a concatenation operation defined for each user-defined
1142 -- one-dimensional array.
1144 procedure Analyze_Concatenation_Rest (N : Node_Id) is
1145 L : constant Node_Id := Left_Opnd (N);
1146 R : constant Node_Id := Right_Opnd (N);
1147 Op_Id : Entity_Id := Entity (N);
1152 Analyze_Expression (R);
1154 -- If the entity is present, the node appears in an instance, and
1155 -- denotes a predefined concatenation operation. The resulting type is
1156 -- obtained from the arguments when possible. If the arguments are
1157 -- aggregates, the array type and the concatenation type must be
1160 if Present (Op_Id) then
1161 if Ekind (Op_Id) = E_Operator then
1163 LT := Base_Type (Etype (L));
1164 RT := Base_Type (Etype (R));
1166 if Is_Array_Type (LT)
1167 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
1169 Add_One_Interp (N, Op_Id, LT);
1171 elsif Is_Array_Type (RT)
1172 and then LT = Base_Type (Component_Type (RT))
1174 Add_One_Interp (N, Op_Id, RT);
1176 -- If one operand is a string type or a user-defined array type,
1177 -- and the other is a literal, result is of the specific type.
1180 (Root_Type (LT) = Standard_String
1181 or else Scope (LT) /= Standard_Standard)
1182 and then Etype (R) = Any_String
1184 Add_One_Interp (N, Op_Id, LT);
1187 (Root_Type (RT) = Standard_String
1188 or else Scope (RT) /= Standard_Standard)
1189 and then Etype (L) = Any_String
1191 Add_One_Interp (N, Op_Id, RT);
1193 elsif not Is_Generic_Type (Etype (Op_Id)) then
1194 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1197 -- Type and its operations must be visible
1199 Set_Entity (N, Empty);
1200 Analyze_Concatenation (N);
1204 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1208 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
1209 while Present (Op_Id) loop
1210 if Ekind (Op_Id) = E_Operator then
1212 -- Do not consider operators declared in dead code, they can
1213 -- not be part of the resolution.
1215 if Is_Eliminated (Op_Id) then
1218 Find_Concatenation_Types (L, R, Op_Id, N);
1222 Analyze_User_Defined_Binary_Op (N, Op_Id);
1225 Op_Id := Homonym (Op_Id);
1230 end Analyze_Concatenation_Rest;
1232 ------------------------------------
1233 -- Analyze_Conditional_Expression --
1234 ------------------------------------
1236 procedure Analyze_Conditional_Expression (N : Node_Id) is
1237 Condition : constant Node_Id := First (Expressions (N));
1238 Then_Expr : constant Node_Id := Next (Condition);
1239 Else_Expr : constant Node_Id := Next (Then_Expr);
1241 Analyze_Expression (Condition);
1242 Analyze_Expression (Then_Expr);
1243 Analyze_Expression (Else_Expr);
1244 Set_Etype (N, Etype (Then_Expr));
1245 end Analyze_Conditional_Expression;
1247 -------------------------
1248 -- Analyze_Equality_Op --
1249 -------------------------
1251 procedure Analyze_Equality_Op (N : Node_Id) is
1252 Loc : constant Source_Ptr := Sloc (N);
1253 L : constant Node_Id := Left_Opnd (N);
1254 R : constant Node_Id := Right_Opnd (N);
1258 Set_Etype (N, Any_Type);
1259 Candidate_Type := Empty;
1261 Analyze_Expression (L);
1262 Analyze_Expression (R);
1264 -- If the entity is set, the node is a generic instance with a non-local
1265 -- reference to the predefined operator or to a user-defined function.
1266 -- It can also be an inequality that is expanded into the negation of a
1267 -- call to a user-defined equality operator.
1269 -- For the predefined case, the result is Boolean, regardless of the
1270 -- type of the operands. The operands may even be limited, if they are
1271 -- generic actuals. If they are overloaded, label the left argument with
1272 -- the common type that must be present, or with the type of the formal
1273 -- of the user-defined function.
1275 if Present (Entity (N)) then
1276 Op_Id := Entity (N);
1278 if Ekind (Op_Id) = E_Operator then
1279 Add_One_Interp (N, Op_Id, Standard_Boolean);
1281 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1284 if Is_Overloaded (L) then
1285 if Ekind (Op_Id) = E_Operator then
1286 Set_Etype (L, Intersect_Types (L, R));
1288 Set_Etype (L, Etype (First_Formal (Op_Id)));
1293 Op_Id := Get_Name_Entity_Id (Chars (N));
1294 while Present (Op_Id) loop
1295 if Ekind (Op_Id) = E_Operator then
1296 Find_Equality_Types (L, R, Op_Id, N);
1298 Analyze_User_Defined_Binary_Op (N, Op_Id);
1301 Op_Id := Homonym (Op_Id);
1305 -- If there was no match, and the operator is inequality, this may
1306 -- be a case where inequality has not been made explicit, as for
1307 -- tagged types. Analyze the node as the negation of an equality
1308 -- operation. This cannot be done earlier, because before analysis
1309 -- we cannot rule out the presence of an explicit inequality.
1311 if Etype (N) = Any_Type
1312 and then Nkind (N) = N_Op_Ne
1314 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1315 while Present (Op_Id) loop
1316 if Ekind (Op_Id) = E_Operator then
1317 Find_Equality_Types (L, R, Op_Id, N);
1319 Analyze_User_Defined_Binary_Op (N, Op_Id);
1322 Op_Id := Homonym (Op_Id);
1325 if Etype (N) /= Any_Type then
1326 Op_Id := Entity (N);
1332 Left_Opnd => Left_Opnd (N),
1333 Right_Opnd => Right_Opnd (N))));
1335 Set_Entity (Right_Opnd (N), Op_Id);
1341 end Analyze_Equality_Op;
1343 ----------------------------------
1344 -- Analyze_Explicit_Dereference --
1345 ----------------------------------
1347 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1348 Loc : constant Source_Ptr := Sloc (N);
1349 P : constant Node_Id := Prefix (N);
1355 function Is_Function_Type return Boolean;
1356 -- Check whether node may be interpreted as an implicit function call
1358 ----------------------
1359 -- Is_Function_Type --
1360 ----------------------
1362 function Is_Function_Type return Boolean is
1367 if not Is_Overloaded (N) then
1368 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1369 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1372 Get_First_Interp (N, I, It);
1373 while Present (It.Nam) loop
1374 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1375 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1380 Get_Next_Interp (I, It);
1385 end Is_Function_Type;
1387 -- Start of processing for Analyze_Explicit_Dereference
1391 Set_Etype (N, Any_Type);
1393 -- Test for remote access to subprogram type, and if so return
1394 -- after rewriting the original tree.
1396 if Remote_AST_E_Dereference (P) then
1400 -- Normal processing for other than remote access to subprogram type
1402 if not Is_Overloaded (P) then
1403 if Is_Access_Type (Etype (P)) then
1405 -- Set the Etype. We need to go through Is_For_Access_Subtypes to
1406 -- avoid other problems caused by the Private_Subtype and it is
1407 -- safe to go to the Base_Type because this is the same as
1408 -- converting the access value to its Base_Type.
1411 DT : Entity_Id := Designated_Type (Etype (P));
1414 if Ekind (DT) = E_Private_Subtype
1415 and then Is_For_Access_Subtype (DT)
1417 DT := Base_Type (DT);
1420 -- An explicit dereference is a legal occurrence of an
1421 -- incomplete type imported through a limited_with clause,
1422 -- if the full view is visible.
1424 if From_With_Type (DT)
1425 and then not From_With_Type (Scope (DT))
1427 (Is_Immediately_Visible (Scope (DT))
1429 (Is_Child_Unit (Scope (DT))
1430 and then Is_Visible_Child_Unit (Scope (DT))))
1432 Set_Etype (N, Available_View (DT));
1439 elsif Etype (P) /= Any_Type then
1440 Error_Msg_N ("prefix of dereference must be an access type", N);
1445 Get_First_Interp (P, I, It);
1446 while Present (It.Nam) loop
1449 if Is_Access_Type (T) then
1450 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1453 Get_Next_Interp (I, It);
1456 -- Error if no interpretation of the prefix has an access type
1458 if Etype (N) = Any_Type then
1460 ("access type required in prefix of explicit dereference", P);
1461 Set_Etype (N, Any_Type);
1467 and then Nkind (Parent (N)) /= N_Indexed_Component
1469 and then (Nkind (Parent (N)) /= N_Function_Call
1470 or else N /= Name (Parent (N)))
1472 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1473 or else N /= Name (Parent (N)))
1475 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1476 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1478 (Attribute_Name (Parent (N)) /= Name_Address
1480 Attribute_Name (Parent (N)) /= Name_Access))
1482 -- Name is a function call with no actuals, in a context that
1483 -- requires deproceduring (including as an actual in an enclosing
1484 -- function or procedure call). There are some pathological cases
1485 -- where the prefix might include functions that return access to
1486 -- subprograms and others that return a regular type. Disambiguation
1487 -- of those has to take place in Resolve.
1490 Make_Function_Call (Loc,
1491 Name => Make_Explicit_Dereference (Loc, P),
1492 Parameter_Associations => New_List);
1494 -- If the prefix is overloaded, remove operations that have formals,
1495 -- we know that this is a parameterless call.
1497 if Is_Overloaded (P) then
1498 Get_First_Interp (P, I, It);
1499 while Present (It.Nam) loop
1502 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1508 Get_Next_Interp (I, It);
1515 elsif not Is_Function_Type
1516 and then Is_Overloaded (N)
1518 -- The prefix may include access to subprograms and other access
1519 -- types. If the context selects the interpretation that is a
1520 -- function call (not a procedure call) we cannot rewrite the node
1521 -- yet, but we include the result of the call interpretation.
1523 Get_First_Interp (N, I, It);
1524 while Present (It.Nam) loop
1525 if Ekind (Base_Type (It.Typ)) = E_Subprogram_Type
1526 and then Etype (Base_Type (It.Typ)) /= Standard_Void_Type
1527 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
1529 Add_One_Interp (N, Etype (It.Typ), Etype (It.Typ));
1532 Get_Next_Interp (I, It);
1536 -- A value of remote access-to-class-wide must not be dereferenced
1539 Validate_Remote_Access_To_Class_Wide_Type (N);
1540 end Analyze_Explicit_Dereference;
1542 ------------------------
1543 -- Analyze_Expression --
1544 ------------------------
1546 procedure Analyze_Expression (N : Node_Id) is
1549 Check_Parameterless_Call (N);
1550 end Analyze_Expression;
1552 ------------------------------------
1553 -- Analyze_Indexed_Component_Form --
1554 ------------------------------------
1556 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1557 P : constant Node_Id := Prefix (N);
1558 Exprs : constant List_Id := Expressions (N);
1564 procedure Process_Function_Call;
1565 -- Prefix in indexed component form is an overloadable entity,
1566 -- so the node is a function call. Reformat it as such.
1568 procedure Process_Indexed_Component;
1569 -- Prefix in indexed component form is actually an indexed component.
1570 -- This routine processes it, knowing that the prefix is already
1573 procedure Process_Indexed_Component_Or_Slice;
1574 -- An indexed component with a single index may designate a slice if
1575 -- the index is a subtype mark. This routine disambiguates these two
1576 -- cases by resolving the prefix to see if it is a subtype mark.
1578 procedure Process_Overloaded_Indexed_Component;
1579 -- If the prefix of an indexed component is overloaded, the proper
1580 -- interpretation is selected by the index types and the context.
1582 ---------------------------
1583 -- Process_Function_Call --
1584 ---------------------------
1586 procedure Process_Function_Call is
1590 Change_Node (N, N_Function_Call);
1592 Set_Parameter_Associations (N, Exprs);
1594 -- Analyze actuals prior to analyzing the call itself
1596 Actual := First (Parameter_Associations (N));
1597 while Present (Actual) loop
1599 Check_Parameterless_Call (Actual);
1601 -- Move to next actual. Note that we use Next, not Next_Actual
1602 -- here. The reason for this is a bit subtle. If a function call
1603 -- includes named associations, the parser recognizes the node as
1604 -- a call, and it is analyzed as such. If all associations are
1605 -- positional, the parser builds an indexed_component node, and
1606 -- it is only after analysis of the prefix that the construct
1607 -- is recognized as a call, in which case Process_Function_Call
1608 -- rewrites the node and analyzes the actuals. If the list of
1609 -- actuals is malformed, the parser may leave the node as an
1610 -- indexed component (despite the presence of named associations).
1611 -- The iterator Next_Actual is equivalent to Next if the list is
1612 -- positional, but follows the normalized chain of actuals when
1613 -- named associations are present. In this case normalization has
1614 -- not taken place, and actuals remain unanalyzed, which leads to
1615 -- subsequent crashes or loops if there is an attempt to continue
1616 -- analysis of the program.
1622 end Process_Function_Call;
1624 -------------------------------
1625 -- Process_Indexed_Component --
1626 -------------------------------
1628 procedure Process_Indexed_Component is
1630 Array_Type : Entity_Id;
1632 Pent : Entity_Id := Empty;
1635 Exp := First (Exprs);
1637 if Is_Overloaded (P) then
1638 Process_Overloaded_Indexed_Component;
1641 Array_Type := Etype (P);
1643 if Is_Entity_Name (P) then
1645 elsif Nkind (P) = N_Selected_Component
1646 and then Is_Entity_Name (Selector_Name (P))
1648 Pent := Entity (Selector_Name (P));
1651 -- Prefix must be appropriate for an array type, taking into
1652 -- account a possible implicit dereference.
1654 if Is_Access_Type (Array_Type) then
1655 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1656 Array_Type := Process_Implicit_Dereference_Prefix (Pent, P);
1659 if Is_Array_Type (Array_Type) then
1662 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1664 Set_Etype (N, Any_Type);
1666 if not Has_Compatible_Type
1667 (Exp, Entry_Index_Type (Pent))
1669 Error_Msg_N ("invalid index type in entry name", N);
1671 elsif Present (Next (Exp)) then
1672 Error_Msg_N ("too many subscripts in entry reference", N);
1675 Set_Etype (N, Etype (P));
1680 elsif Is_Record_Type (Array_Type)
1681 and then Remote_AST_I_Dereference (P)
1685 elsif Array_Type = Any_Type then
1686 Set_Etype (N, Any_Type);
1689 -- Here we definitely have a bad indexing
1692 if Nkind (Parent (N)) = N_Requeue_Statement
1693 and then Present (Pent) and then Ekind (Pent) = E_Entry
1696 ("REQUEUE does not permit parameters", First (Exprs));
1698 elsif Is_Entity_Name (P)
1699 and then Etype (P) = Standard_Void_Type
1701 Error_Msg_NE ("incorrect use of&", P, Entity (P));
1704 Error_Msg_N ("array type required in indexed component", P);
1707 Set_Etype (N, Any_Type);
1711 Index := First_Index (Array_Type);
1712 while Present (Index) and then Present (Exp) loop
1713 if not Has_Compatible_Type (Exp, Etype (Index)) then
1714 Wrong_Type (Exp, Etype (Index));
1715 Set_Etype (N, Any_Type);
1723 Set_Etype (N, Component_Type (Array_Type));
1725 if Present (Index) then
1727 ("too few subscripts in array reference", First (Exprs));
1729 elsif Present (Exp) then
1730 Error_Msg_N ("too many subscripts in array reference", Exp);
1733 end Process_Indexed_Component;
1735 ----------------------------------------
1736 -- Process_Indexed_Component_Or_Slice --
1737 ----------------------------------------
1739 procedure Process_Indexed_Component_Or_Slice is
1741 Exp := First (Exprs);
1742 while Present (Exp) loop
1743 Analyze_Expression (Exp);
1747 Exp := First (Exprs);
1749 -- If one index is present, and it is a subtype name, then the
1750 -- node denotes a slice (note that the case of an explicit range
1751 -- for a slice was already built as an N_Slice node in the first
1752 -- place, so that case is not handled here).
1754 -- We use a replace rather than a rewrite here because this is one
1755 -- of the cases in which the tree built by the parser is plain wrong.
1758 and then Is_Entity_Name (Exp)
1759 and then Is_Type (Entity (Exp))
1762 Make_Slice (Sloc (N),
1764 Discrete_Range => New_Copy (Exp)));
1767 -- Otherwise (more than one index present, or single index is not
1768 -- a subtype name), then we have the indexed component case.
1771 Process_Indexed_Component;
1773 end Process_Indexed_Component_Or_Slice;
1775 ------------------------------------------
1776 -- Process_Overloaded_Indexed_Component --
1777 ------------------------------------------
1779 procedure Process_Overloaded_Indexed_Component is
1788 Set_Etype (N, Any_Type);
1790 Get_First_Interp (P, I, It);
1791 while Present (It.Nam) loop
1794 if Is_Access_Type (Typ) then
1795 Typ := Designated_Type (Typ);
1796 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1799 if Is_Array_Type (Typ) then
1801 -- Got a candidate: verify that index types are compatible
1803 Index := First_Index (Typ);
1805 Exp := First (Exprs);
1806 while Present (Index) and then Present (Exp) loop
1807 if Has_Compatible_Type (Exp, Etype (Index)) then
1819 if Found and then No (Index) and then No (Exp) then
1821 Etype (Component_Type (Typ)),
1822 Etype (Component_Type (Typ)));
1826 Get_Next_Interp (I, It);
1829 if Etype (N) = Any_Type then
1830 Error_Msg_N ("no legal interpretation for indexed component", N);
1831 Set_Is_Overloaded (N, False);
1835 end Process_Overloaded_Indexed_Component;
1837 -- Start of processing for Analyze_Indexed_Component_Form
1840 -- Get name of array, function or type
1844 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement) then
1846 -- If P is an explicit dereference whose prefix is of a
1847 -- remote access-to-subprogram type, then N has already
1848 -- been rewritten as a subprogram call and analyzed.
1853 pragma Assert (Nkind (N) = N_Indexed_Component);
1855 P_T := Base_Type (Etype (P));
1857 if Is_Entity_Name (P)
1858 or else Nkind (P) = N_Operator_Symbol
1862 if Is_Type (U_N) then
1864 -- Reformat node as a type conversion
1866 E := Remove_Head (Exprs);
1868 if Present (First (Exprs)) then
1870 ("argument of type conversion must be single expression", N);
1873 Change_Node (N, N_Type_Conversion);
1874 Set_Subtype_Mark (N, P);
1876 Set_Expression (N, E);
1878 -- After changing the node, call for the specific Analysis
1879 -- routine directly, to avoid a double call to the expander.
1881 Analyze_Type_Conversion (N);
1885 if Is_Overloadable (U_N) then
1886 Process_Function_Call;
1888 elsif Ekind (Etype (P)) = E_Subprogram_Type
1889 or else (Is_Access_Type (Etype (P))
1891 Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type)
1893 -- Call to access_to-subprogram with possible implicit dereference
1895 Process_Function_Call;
1897 elsif Is_Generic_Subprogram (U_N) then
1899 -- A common beginner's (or C++ templates fan) error
1901 Error_Msg_N ("generic subprogram cannot be called", N);
1902 Set_Etype (N, Any_Type);
1906 Process_Indexed_Component_Or_Slice;
1909 -- If not an entity name, prefix is an expression that may denote
1910 -- an array or an access-to-subprogram.
1913 if Ekind (P_T) = E_Subprogram_Type
1914 or else (Is_Access_Type (P_T)
1916 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
1918 Process_Function_Call;
1920 elsif Nkind (P) = N_Selected_Component
1921 and then Is_Overloadable (Entity (Selector_Name (P)))
1923 Process_Function_Call;
1926 -- Indexed component, slice, or a call to a member of a family
1927 -- entry, which will be converted to an entry call later.
1929 Process_Indexed_Component_Or_Slice;
1932 end Analyze_Indexed_Component_Form;
1934 ------------------------
1935 -- Analyze_Logical_Op --
1936 ------------------------
1938 procedure Analyze_Logical_Op (N : Node_Id) is
1939 L : constant Node_Id := Left_Opnd (N);
1940 R : constant Node_Id := Right_Opnd (N);
1941 Op_Id : Entity_Id := Entity (N);
1944 Set_Etype (N, Any_Type);
1945 Candidate_Type := Empty;
1947 Analyze_Expression (L);
1948 Analyze_Expression (R);
1950 if Present (Op_Id) then
1952 if Ekind (Op_Id) = E_Operator then
1953 Find_Boolean_Types (L, R, Op_Id, N);
1955 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1959 Op_Id := Get_Name_Entity_Id (Chars (N));
1960 while Present (Op_Id) loop
1961 if Ekind (Op_Id) = E_Operator then
1962 Find_Boolean_Types (L, R, Op_Id, N);
1964 Analyze_User_Defined_Binary_Op (N, Op_Id);
1967 Op_Id := Homonym (Op_Id);
1972 end Analyze_Logical_Op;
1974 ---------------------------
1975 -- Analyze_Membership_Op --
1976 ---------------------------
1978 procedure Analyze_Membership_Op (N : Node_Id) is
1979 L : constant Node_Id := Left_Opnd (N);
1980 R : constant Node_Id := Right_Opnd (N);
1982 Index : Interp_Index;
1984 Found : Boolean := False;
1988 procedure Try_One_Interp (T1 : Entity_Id);
1989 -- Routine to try one proposed interpretation. Note that the context
1990 -- of the operation plays no role in resolving the arguments, so that
1991 -- if there is more than one interpretation of the operands that is
1992 -- compatible with a membership test, the operation is ambiguous.
1994 --------------------
1995 -- Try_One_Interp --
1996 --------------------
1998 procedure Try_One_Interp (T1 : Entity_Id) is
2000 if Has_Compatible_Type (R, T1) then
2002 and then Base_Type (T1) /= Base_Type (T_F)
2004 It := Disambiguate (L, I_F, Index, Any_Type);
2006 if It = No_Interp then
2007 Ambiguous_Operands (N);
2008 Set_Etype (L, Any_Type);
2026 -- Start of processing for Analyze_Membership_Op
2029 Analyze_Expression (L);
2031 if Nkind (R) = N_Range
2032 or else (Nkind (R) = N_Attribute_Reference
2033 and then Attribute_Name (R) = Name_Range)
2037 if not Is_Overloaded (L) then
2038 Try_One_Interp (Etype (L));
2041 Get_First_Interp (L, Index, It);
2042 while Present (It.Typ) loop
2043 Try_One_Interp (It.Typ);
2044 Get_Next_Interp (Index, It);
2048 -- If not a range, it can only be a subtype mark, or else there
2049 -- is a more basic error, to be diagnosed in Find_Type.
2054 if Is_Entity_Name (R) then
2055 Check_Fully_Declared (Entity (R), R);
2059 -- Compatibility between expression and subtype mark or range is
2060 -- checked during resolution. The result of the operation is Boolean
2063 Set_Etype (N, Standard_Boolean);
2065 if Comes_From_Source (N)
2066 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2068 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2070 end Analyze_Membership_Op;
2072 ----------------------
2073 -- Analyze_Negation --
2074 ----------------------
2076 procedure Analyze_Negation (N : Node_Id) is
2077 R : constant Node_Id := Right_Opnd (N);
2078 Op_Id : Entity_Id := Entity (N);
2081 Set_Etype (N, Any_Type);
2082 Candidate_Type := Empty;
2084 Analyze_Expression (R);
2086 if Present (Op_Id) then
2087 if Ekind (Op_Id) = E_Operator then
2088 Find_Negation_Types (R, Op_Id, N);
2090 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2094 Op_Id := Get_Name_Entity_Id (Chars (N));
2095 while Present (Op_Id) loop
2096 if Ekind (Op_Id) = E_Operator then
2097 Find_Negation_Types (R, Op_Id, N);
2099 Analyze_User_Defined_Unary_Op (N, Op_Id);
2102 Op_Id := Homonym (Op_Id);
2107 end Analyze_Negation;
2113 procedure Analyze_Null (N : Node_Id) is
2115 Set_Etype (N, Any_Access);
2118 ----------------------
2119 -- Analyze_One_Call --
2120 ----------------------
2122 procedure Analyze_One_Call
2126 Success : out Boolean;
2127 Skip_First : Boolean := False)
2129 Actuals : constant List_Id := Parameter_Associations (N);
2130 Prev_T : constant Entity_Id := Etype (N);
2132 Must_Skip : constant Boolean := Skip_First
2133 or else Nkind (Original_Node (N)) = N_Selected_Component
2135 (Nkind (Original_Node (N)) = N_Indexed_Component
2136 and then Nkind (Prefix (Original_Node (N)))
2137 = N_Selected_Component);
2138 -- The first formal must be omitted from the match when trying to find
2139 -- a primitive operation that is a possible interpretation, and also
2140 -- after the call has been rewritten, because the corresponding actual
2141 -- is already known to be compatible, and because this may be an
2142 -- indexing of a call with default parameters.
2146 Is_Indexed : Boolean := False;
2147 Is_Indirect : Boolean := False;
2148 Subp_Type : constant Entity_Id := Etype (Nam);
2151 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2152 -- There may be a user-defined operator that hides the current
2153 -- interpretation. We must check for this independently of the
2154 -- analysis of the call with the user-defined operation, because
2155 -- the parameter names may be wrong and yet the hiding takes place.
2156 -- This fixes a problem with ACATS test B34014O.
2158 -- When the type Address is a visible integer type, and the DEC
2159 -- system extension is visible, the predefined operator may be
2160 -- hidden as well, by one of the address operations in auxdec.
2161 -- Finally, The abstract operations on address do not hide the
2162 -- predefined operator (this is the purpose of making them abstract).
2164 procedure Indicate_Name_And_Type;
2165 -- If candidate interpretation matches, indicate name and type of
2166 -- result on call node.
2168 ----------------------------
2169 -- Indicate_Name_And_Type --
2170 ----------------------------
2172 procedure Indicate_Name_And_Type is
2174 Add_One_Interp (N, Nam, Etype (Nam));
2177 -- If the prefix of the call is a name, indicate the entity
2178 -- being called. If it is not a name, it is an expression that
2179 -- denotes an access to subprogram or else an entry or family. In
2180 -- the latter case, the name is a selected component, and the entity
2181 -- being called is noted on the selector.
2183 if not Is_Type (Nam) then
2184 if Is_Entity_Name (Name (N))
2185 or else Nkind (Name (N)) = N_Operator_Symbol
2187 Set_Entity (Name (N), Nam);
2189 elsif Nkind (Name (N)) = N_Selected_Component then
2190 Set_Entity (Selector_Name (Name (N)), Nam);
2194 if Debug_Flag_E and not Report then
2195 Write_Str (" Overloaded call ");
2196 Write_Int (Int (N));
2197 Write_Str (" compatible with ");
2198 Write_Int (Int (Nam));
2201 end Indicate_Name_And_Type;
2203 ------------------------
2204 -- Operator_Hidden_By --
2205 ------------------------
2207 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2208 Act1 : constant Node_Id := First_Actual (N);
2209 Act2 : constant Node_Id := Next_Actual (Act1);
2210 Form1 : constant Entity_Id := First_Formal (Fun);
2211 Form2 : constant Entity_Id := Next_Formal (Form1);
2214 if Ekind (Fun) /= E_Function
2215 or else Is_Abstract_Subprogram (Fun)
2219 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2222 elsif Present (Form2) then
2224 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2229 elsif Present (Act2) then
2233 -- Now we know that the arity of the operator matches the function,
2234 -- and the function call is a valid interpretation. The function
2235 -- hides the operator if it has the right signature, or if one of
2236 -- its operands is a non-abstract operation on Address when this is
2237 -- a visible integer type.
2239 return Hides_Op (Fun, Nam)
2240 or else Is_Descendent_Of_Address (Etype (Form1))
2243 and then Is_Descendent_Of_Address (Etype (Form2)));
2244 end Operator_Hidden_By;
2246 -- Start of processing for Analyze_One_Call
2251 -- If the subprogram has no formals or if all the formals have defaults,
2252 -- and the return type is an array type, the node may denote an indexing
2253 -- of the result of a parameterless call. In Ada 2005, the subprogram
2254 -- may have one non-defaulted formal, and the call may have been written
2255 -- in prefix notation, so that the rebuilt parameter list has more than
2258 if not Is_Overloadable (Nam)
2259 and then Ekind (Nam) /= E_Subprogram_Type
2260 and then Ekind (Nam) /= E_Entry_Family
2265 if Present (Actuals)
2267 (Needs_No_Actuals (Nam)
2269 (Needs_One_Actual (Nam)
2270 and then Present (Next_Actual (First (Actuals)))))
2272 if Is_Array_Type (Subp_Type) then
2273 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2275 elsif Is_Access_Type (Subp_Type)
2276 and then Is_Array_Type (Designated_Type (Subp_Type))
2280 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2282 -- The prefix can also be a parameterless function that returns an
2283 -- access to subprogram, in which case this is an indirect call.
2284 -- If this succeeds, an explicit dereference is added later on,
2285 -- in Analyze_Call or Resolve_Call.
2287 elsif Is_Access_Type (Subp_Type)
2288 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2290 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2295 -- If the call has been transformed into a slice, it is of the form
2296 -- F (Subtype) where F is parameterless. The node has been rewritten in
2297 -- Try_Indexed_Call and there is nothing else to do.
2300 and then Nkind (N) = N_Slice
2306 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2310 -- If an indirect call is a possible interpretation, indicate
2311 -- success to the caller.
2317 -- Mismatch in number or names of parameters
2319 elsif Debug_Flag_E then
2320 Write_Str (" normalization fails in call ");
2321 Write_Int (Int (N));
2322 Write_Str (" with subprogram ");
2323 Write_Int (Int (Nam));
2327 -- If the context expects a function call, discard any interpretation
2328 -- that is a procedure. If the node is not overloaded, leave as is for
2329 -- better error reporting when type mismatch is found.
2331 elsif Nkind (N) = N_Function_Call
2332 and then Is_Overloaded (Name (N))
2333 and then Ekind (Nam) = E_Procedure
2337 -- Ditto for function calls in a procedure context
2339 elsif Nkind (N) = N_Procedure_Call_Statement
2340 and then Is_Overloaded (Name (N))
2341 and then Etype (Nam) /= Standard_Void_Type
2345 elsif No (Actuals) then
2347 -- If Normalize succeeds, then there are default parameters for
2350 Indicate_Name_And_Type;
2352 elsif Ekind (Nam) = E_Operator then
2353 if Nkind (N) = N_Procedure_Call_Statement then
2357 -- This can occur when the prefix of the call is an operator
2358 -- name or an expanded name whose selector is an operator name.
2360 Analyze_Operator_Call (N, Nam);
2362 if Etype (N) /= Prev_T then
2364 -- Check that operator is not hidden by a function interpretation
2366 if Is_Overloaded (Name (N)) then
2372 Get_First_Interp (Name (N), I, It);
2373 while Present (It.Nam) loop
2374 if Operator_Hidden_By (It.Nam) then
2375 Set_Etype (N, Prev_T);
2379 Get_Next_Interp (I, It);
2384 -- If operator matches formals, record its name on the call.
2385 -- If the operator is overloaded, Resolve will select the
2386 -- correct one from the list of interpretations. The call
2387 -- node itself carries the first candidate.
2389 Set_Entity (Name (N), Nam);
2392 elsif Report and then Etype (N) = Any_Type then
2393 Error_Msg_N ("incompatible arguments for operator", N);
2397 -- Normalize_Actuals has chained the named associations in the
2398 -- correct order of the formals.
2400 Actual := First_Actual (N);
2401 Formal := First_Formal (Nam);
2403 -- If we are analyzing a call rewritten from object notation,
2404 -- skip first actual, which may be rewritten later as an
2405 -- explicit dereference.
2408 Next_Actual (Actual);
2409 Next_Formal (Formal);
2412 while Present (Actual) and then Present (Formal) loop
2413 if Nkind (Parent (Actual)) /= N_Parameter_Association
2414 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2416 -- The actual can be compatible with the formal, but we must
2417 -- also check that the context is not an address type that is
2418 -- visibly an integer type, as is the case in VMS_64. In this
2419 -- case the use of literals is illegal, except in the body of
2420 -- descendents of system, where arithmetic operations on
2421 -- address are of course used.
2423 if Has_Compatible_Type (Actual, Etype (Formal))
2425 (Etype (Actual) /= Universal_Integer
2426 or else not Is_Descendent_Of_Address (Etype (Formal))
2428 Is_Predefined_File_Name
2429 (Unit_File_Name (Get_Source_Unit (N))))
2431 Next_Actual (Actual);
2432 Next_Formal (Formal);
2435 if Debug_Flag_E then
2436 Write_Str (" type checking fails in call ");
2437 Write_Int (Int (N));
2438 Write_Str (" with formal ");
2439 Write_Int (Int (Formal));
2440 Write_Str (" in subprogram ");
2441 Write_Int (Int (Nam));
2445 if Report and not Is_Indexed and not Is_Indirect then
2447 -- Ada 2005 (AI-251): Complete the error notification
2448 -- to help new Ada 2005 users
2450 if Is_Class_Wide_Type (Etype (Formal))
2451 and then Is_Interface (Etype (Etype (Formal)))
2452 and then not Interface_Present_In_Ancestor
2453 (Typ => Etype (Actual),
2454 Iface => Etype (Etype (Formal)))
2457 ("(Ada 2005) does not implement interface }",
2458 Actual, Etype (Etype (Formal)));
2461 Wrong_Type (Actual, Etype (Formal));
2463 if Nkind (Actual) = N_Op_Eq
2464 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2466 Formal := First_Formal (Nam);
2467 while Present (Formal) loop
2468 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2470 ("possible misspelling of `='>`!", Actual);
2474 Next_Formal (Formal);
2478 if All_Errors_Mode then
2479 Error_Msg_Sloc := Sloc (Nam);
2481 if Is_Overloadable (Nam)
2482 and then Present (Alias (Nam))
2483 and then not Comes_From_Source (Nam)
2486 ("\\ =='> in call to inherited operation & #!",
2489 elsif Ekind (Nam) = E_Subprogram_Type then
2491 Access_To_Subprogram_Typ :
2492 constant Entity_Id :=
2494 (Associated_Node_For_Itype (Nam));
2497 "\\ =='> in call to dereference of &#!",
2498 Actual, Access_To_Subprogram_Typ);
2503 ("\\ =='> in call to &#!", Actual, Nam);
2513 -- Normalize_Actuals has verified that a default value exists
2514 -- for this formal. Current actual names a subsequent formal.
2516 Next_Formal (Formal);
2520 -- On exit, all actuals match
2522 Indicate_Name_And_Type;
2524 end Analyze_One_Call;
2526 ---------------------------
2527 -- Analyze_Operator_Call --
2528 ---------------------------
2530 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2531 Op_Name : constant Name_Id := Chars (Op_Id);
2532 Act1 : constant Node_Id := First_Actual (N);
2533 Act2 : constant Node_Id := Next_Actual (Act1);
2536 -- Binary operator case
2538 if Present (Act2) then
2540 -- If more than two operands, then not binary operator after all
2542 if Present (Next_Actual (Act2)) then
2545 elsif Op_Name = Name_Op_Add
2546 or else Op_Name = Name_Op_Subtract
2547 or else Op_Name = Name_Op_Multiply
2548 or else Op_Name = Name_Op_Divide
2549 or else Op_Name = Name_Op_Mod
2550 or else Op_Name = Name_Op_Rem
2551 or else Op_Name = Name_Op_Expon
2553 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2555 elsif Op_Name = Name_Op_And
2556 or else Op_Name = Name_Op_Or
2557 or else Op_Name = Name_Op_Xor
2559 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2561 elsif Op_Name = Name_Op_Lt
2562 or else Op_Name = Name_Op_Le
2563 or else Op_Name = Name_Op_Gt
2564 or else Op_Name = Name_Op_Ge
2566 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2568 elsif Op_Name = Name_Op_Eq
2569 or else Op_Name = Name_Op_Ne
2571 Find_Equality_Types (Act1, Act2, Op_Id, N);
2573 elsif Op_Name = Name_Op_Concat then
2574 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2576 -- Is this else null correct, or should it be an abort???
2582 -- Unary operator case
2585 if Op_Name = Name_Op_Subtract or else
2586 Op_Name = Name_Op_Add or else
2587 Op_Name = Name_Op_Abs
2589 Find_Unary_Types (Act1, Op_Id, N);
2592 Op_Name = Name_Op_Not
2594 Find_Negation_Types (Act1, Op_Id, N);
2596 -- Is this else null correct, or should it be an abort???
2602 end Analyze_Operator_Call;
2604 -------------------------------------------
2605 -- Analyze_Overloaded_Selected_Component --
2606 -------------------------------------------
2608 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
2609 Nam : constant Node_Id := Prefix (N);
2610 Sel : constant Node_Id := Selector_Name (N);
2617 Set_Etype (Sel, Any_Type);
2619 Get_First_Interp (Nam, I, It);
2620 while Present (It.Typ) loop
2621 if Is_Access_Type (It.Typ) then
2622 T := Designated_Type (It.Typ);
2623 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2628 if Is_Record_Type (T) then
2630 -- If the prefix is a class-wide type, the visible components are
2631 -- those of the base type.
2633 if Is_Class_Wide_Type (T) then
2637 Comp := First_Entity (T);
2638 while Present (Comp) loop
2639 if Chars (Comp) = Chars (Sel)
2640 and then Is_Visible_Component (Comp)
2643 -- AI05-105: if the context is an object renaming with
2644 -- an anonymous access type, the expected type of the
2645 -- object must be anonymous. This is a name resolution rule.
2647 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
2648 or else No (Access_Definition (Parent (N)))
2649 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
2651 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
2653 Set_Entity (Sel, Comp);
2654 Set_Etype (Sel, Etype (Comp));
2655 Add_One_Interp (N, Etype (Comp), Etype (Comp));
2657 -- This also specifies a candidate to resolve the name.
2658 -- Further overloading will be resolved from context.
2659 -- The selector name itself does not carry overloading
2662 Set_Etype (Nam, It.Typ);
2665 -- Named access type in the context of a renaming
2666 -- declaration with an access definition. Remove
2667 -- inapplicable candidate.
2676 elsif Is_Concurrent_Type (T) then
2677 Comp := First_Entity (T);
2678 while Present (Comp)
2679 and then Comp /= First_Private_Entity (T)
2681 if Chars (Comp) = Chars (Sel) then
2682 if Is_Overloadable (Comp) then
2683 Add_One_Interp (Sel, Comp, Etype (Comp));
2685 Set_Entity_With_Style_Check (Sel, Comp);
2686 Generate_Reference (Comp, Sel);
2689 Set_Etype (Sel, Etype (Comp));
2690 Set_Etype (N, Etype (Comp));
2691 Set_Etype (Nam, It.Typ);
2693 -- For access type case, introduce explicit deference for
2694 -- more uniform treatment of entry calls. Do this only
2695 -- once if several interpretations yield an access type.
2697 if Is_Access_Type (Etype (Nam))
2698 and then Nkind (Nam) /= N_Explicit_Dereference
2700 Insert_Explicit_Dereference (Nam);
2702 (Warn_On_Dereference, "?implicit dereference", N);
2709 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2712 Get_Next_Interp (I, It);
2715 if Etype (N) = Any_Type
2716 and then not Try_Object_Operation (N)
2718 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
2719 Set_Entity (Sel, Any_Id);
2720 Set_Etype (Sel, Any_Type);
2722 end Analyze_Overloaded_Selected_Component;
2724 ----------------------------------
2725 -- Analyze_Qualified_Expression --
2726 ----------------------------------
2728 procedure Analyze_Qualified_Expression (N : Node_Id) is
2729 Mark : constant Entity_Id := Subtype_Mark (N);
2730 Expr : constant Node_Id := Expression (N);
2736 Analyze_Expression (Expr);
2738 Set_Etype (N, Any_Type);
2743 if T = Any_Type then
2747 Check_Fully_Declared (T, N);
2749 -- If expected type is class-wide, check for exact match before
2750 -- expansion, because if the expression is a dispatching call it
2751 -- may be rewritten as explicit dereference with class-wide result.
2752 -- If expression is overloaded, retain only interpretations that
2753 -- will yield exact matches.
2755 if Is_Class_Wide_Type (T) then
2756 if not Is_Overloaded (Expr) then
2757 if Base_Type (Etype (Expr)) /= Base_Type (T) then
2758 if Nkind (Expr) = N_Aggregate then
2759 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
2761 Wrong_Type (Expr, T);
2766 Get_First_Interp (Expr, I, It);
2768 while Present (It.Nam) loop
2769 if Base_Type (It.Typ) /= Base_Type (T) then
2773 Get_Next_Interp (I, It);
2779 end Analyze_Qualified_Expression;
2785 procedure Analyze_Range (N : Node_Id) is
2786 L : constant Node_Id := Low_Bound (N);
2787 H : constant Node_Id := High_Bound (N);
2788 I1, I2 : Interp_Index;
2791 procedure Check_Common_Type (T1, T2 : Entity_Id);
2792 -- Verify the compatibility of two types, and choose the
2793 -- non universal one if the other is universal.
2795 procedure Check_High_Bound (T : Entity_Id);
2796 -- Test one interpretation of the low bound against all those
2797 -- of the high bound.
2799 procedure Check_Universal_Expression (N : Node_Id);
2800 -- In Ada83, reject bounds of a universal range that are not
2801 -- literals or entity names.
2803 -----------------------
2804 -- Check_Common_Type --
2805 -----------------------
2807 procedure Check_Common_Type (T1, T2 : Entity_Id) is
2809 if Covers (T1 => T1, T2 => T2)
2811 Covers (T1 => T2, T2 => T1)
2813 if T1 = Universal_Integer
2814 or else T1 = Universal_Real
2815 or else T1 = Any_Character
2817 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
2820 Add_One_Interp (N, T1, T1);
2823 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
2826 end Check_Common_Type;
2828 ----------------------
2829 -- Check_High_Bound --
2830 ----------------------
2832 procedure Check_High_Bound (T : Entity_Id) is
2834 if not Is_Overloaded (H) then
2835 Check_Common_Type (T, Etype (H));
2837 Get_First_Interp (H, I2, It2);
2838 while Present (It2.Typ) loop
2839 Check_Common_Type (T, It2.Typ);
2840 Get_Next_Interp (I2, It2);
2843 end Check_High_Bound;
2845 -----------------------------
2846 -- Is_Universal_Expression --
2847 -----------------------------
2849 procedure Check_Universal_Expression (N : Node_Id) is
2851 if Etype (N) = Universal_Integer
2852 and then Nkind (N) /= N_Integer_Literal
2853 and then not Is_Entity_Name (N)
2854 and then Nkind (N) /= N_Attribute_Reference
2856 Error_Msg_N ("illegal bound in discrete range", N);
2858 end Check_Universal_Expression;
2860 -- Start of processing for Analyze_Range
2863 Set_Etype (N, Any_Type);
2864 Analyze_Expression (L);
2865 Analyze_Expression (H);
2867 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
2871 if not Is_Overloaded (L) then
2872 Check_High_Bound (Etype (L));
2874 Get_First_Interp (L, I1, It1);
2875 while Present (It1.Typ) loop
2876 Check_High_Bound (It1.Typ);
2877 Get_Next_Interp (I1, It1);
2881 -- If result is Any_Type, then we did not find a compatible pair
2883 if Etype (N) = Any_Type then
2884 Error_Msg_N ("incompatible types in range ", N);
2888 if Ada_Version = Ada_83
2890 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
2891 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
2893 Check_Universal_Expression (L);
2894 Check_Universal_Expression (H);
2898 -----------------------
2899 -- Analyze_Reference --
2900 -----------------------
2902 procedure Analyze_Reference (N : Node_Id) is
2903 P : constant Node_Id := Prefix (N);
2906 Acc_Type : Entity_Id;
2911 -- An interesting error check, if we take the 'Reference of an object
2912 -- for which a pragma Atomic or Volatile has been given, and the type
2913 -- of the object is not Atomic or Volatile, then we are in trouble. The
2914 -- problem is that no trace of the atomic/volatile status will remain
2915 -- for the backend to respect when it deals with the resulting pointer,
2916 -- since the pointer type will not be marked atomic (it is a pointer to
2917 -- the base type of the object).
2919 -- It is not clear if that can ever occur, but in case it does, we will
2920 -- generate an error message. Not clear if this message can ever be
2921 -- generated, and pretty clear that it represents a bug if it is, still
2922 -- seems worth checking!
2926 if Is_Entity_Name (P)
2927 and then Is_Object_Reference (P)
2932 if (Has_Atomic_Components (E)
2933 and then not Has_Atomic_Components (T))
2935 (Has_Volatile_Components (E)
2936 and then not Has_Volatile_Components (T))
2937 or else (Is_Atomic (E) and then not Is_Atomic (T))
2938 or else (Is_Volatile (E) and then not Is_Volatile (T))
2940 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
2944 -- Carry on with normal processing
2946 Acc_Type := Create_Itype (E_Allocator_Type, N);
2947 Set_Etype (Acc_Type, Acc_Type);
2948 Set_Directly_Designated_Type (Acc_Type, Etype (P));
2949 Set_Etype (N, Acc_Type);
2950 end Analyze_Reference;
2952 --------------------------------
2953 -- Analyze_Selected_Component --
2954 --------------------------------
2956 -- Prefix is a record type or a task or protected type. In the
2957 -- later case, the selector must denote a visible entry.
2959 procedure Analyze_Selected_Component (N : Node_Id) is
2960 Name : constant Node_Id := Prefix (N);
2961 Sel : constant Node_Id := Selector_Name (N);
2964 Has_Candidate : Boolean := False;
2967 Pent : Entity_Id := Empty;
2968 Prefix_Type : Entity_Id;
2970 Type_To_Use : Entity_Id;
2971 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
2972 -- a class-wide type, we use its root type, whose components are
2973 -- present in the class-wide type.
2975 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
2976 -- It is known that the parent of N denotes a subprogram call. Comp
2977 -- is an overloadable component of the concurrent type of the prefix.
2978 -- Determine whether all formals of the parent of N and Comp are mode
2979 -- conformant. If the parent node is not analyzed yet it may be an
2980 -- indexed component rather than a function call.
2982 ------------------------------
2983 -- Has_Mode_Conformant_Spec --
2984 ------------------------------
2986 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
2987 Comp_Param : Entity_Id;
2989 Param_Typ : Entity_Id;
2992 Comp_Param := First_Formal (Comp);
2994 if Nkind (Parent (N)) = N_Indexed_Component then
2995 Param := First (Expressions (Parent (N)));
2997 Param := First (Parameter_Associations (Parent (N)));
3000 while Present (Comp_Param)
3001 and then Present (Param)
3003 Param_Typ := Find_Parameter_Type (Param);
3005 if Present (Param_Typ)
3007 not Conforming_Types
3008 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3013 Next_Formal (Comp_Param);
3017 -- One of the specs has additional formals
3019 if Present (Comp_Param) or else Present (Param) then
3024 end Has_Mode_Conformant_Spec;
3026 -- Start of processing for Analyze_Selected_Component
3029 Set_Etype (N, Any_Type);
3031 if Is_Overloaded (Name) then
3032 Analyze_Overloaded_Selected_Component (N);
3035 elsif Etype (Name) = Any_Type then
3036 Set_Entity (Sel, Any_Id);
3037 Set_Etype (Sel, Any_Type);
3041 Prefix_Type := Etype (Name);
3044 if Is_Access_Type (Prefix_Type) then
3046 -- A RACW object can never be used as prefix of a selected
3047 -- component since that means it is dereferenced without
3048 -- being a controlling operand of a dispatching operation
3049 -- (RM E.2.2(16/1)). Before reporting an error, we must check
3050 -- whether this is actually a dispatching call in prefix form.
3052 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3053 and then Comes_From_Source (N)
3055 if Try_Object_Operation (N) then
3059 ("invalid dereference of a remote access-to-class-wide value",
3063 -- Normal case of selected component applied to access type
3066 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3068 if Is_Entity_Name (Name) then
3069 Pent := Entity (Name);
3070 elsif Nkind (Name) = N_Selected_Component
3071 and then Is_Entity_Name (Selector_Name (Name))
3073 Pent := Entity (Selector_Name (Name));
3076 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3079 -- If we have an explicit dereference of a remote access-to-class-wide
3080 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3081 -- have to check for the case of a prefix that is a controlling operand
3082 -- of a prefixed dispatching call, as the dereference is legal in that
3083 -- case. Normally this condition is checked in Validate_Remote_Access_
3084 -- To_Class_Wide_Type, but we have to defer the checking for selected
3085 -- component prefixes because of the prefixed dispatching call case.
3086 -- Note that implicit dereferences are checked for this just above.
3088 elsif Nkind (Name) = N_Explicit_Dereference
3089 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3090 and then Comes_From_Source (N)
3092 if Try_Object_Operation (N) then
3096 ("invalid dereference of a remote access-to-class-wide value",
3101 -- (Ada 2005): if the prefix is the limited view of a type, and
3102 -- the context already includes the full view, use the full view
3103 -- in what follows, either to retrieve a component of to find
3104 -- a primitive operation. If the prefix is an explicit dereference,
3105 -- set the type of the prefix to reflect this transformation.
3106 -- If the non-limited view is itself an incomplete type, get the
3107 -- full view if available.
3109 if Is_Incomplete_Type (Prefix_Type)
3110 and then From_With_Type (Prefix_Type)
3111 and then Present (Non_Limited_View (Prefix_Type))
3113 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3115 if Nkind (N) = N_Explicit_Dereference then
3116 Set_Etype (Prefix (N), Prefix_Type);
3119 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3120 and then From_With_Type (Prefix_Type)
3121 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3124 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3126 if Nkind (N) = N_Explicit_Dereference then
3127 Set_Etype (Prefix (N), Prefix_Type);
3131 if Ekind (Prefix_Type) = E_Private_Subtype then
3132 Prefix_Type := Base_Type (Prefix_Type);
3135 Type_To_Use := Prefix_Type;
3137 -- For class-wide types, use the entity list of the root type. This
3138 -- indirection is specially important for private extensions because
3139 -- only the root type get switched (not the class-wide type).
3141 if Is_Class_Wide_Type (Prefix_Type) then
3142 Type_To_Use := Root_Type (Prefix_Type);
3145 Comp := First_Entity (Type_To_Use);
3147 -- If the selector has an original discriminant, the node appears in
3148 -- an instance. Replace the discriminant with the corresponding one
3149 -- in the current discriminated type. For nested generics, this must
3150 -- be done transitively, so note the new original discriminant.
3152 if Nkind (Sel) = N_Identifier
3153 and then Present (Original_Discriminant (Sel))
3155 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3157 -- Mark entity before rewriting, for completeness and because
3158 -- subsequent semantic checks might examine the original node.
3160 Set_Entity (Sel, Comp);
3161 Rewrite (Selector_Name (N),
3162 New_Occurrence_Of (Comp, Sloc (N)));
3163 Set_Original_Discriminant (Selector_Name (N), Comp);
3164 Set_Etype (N, Etype (Comp));
3166 if Is_Access_Type (Etype (Name)) then
3167 Insert_Explicit_Dereference (Name);
3168 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3171 elsif Is_Record_Type (Prefix_Type) then
3173 -- Find component with given name
3175 while Present (Comp) loop
3176 if Chars (Comp) = Chars (Sel)
3177 and then Is_Visible_Component (Comp)
3179 Set_Entity_With_Style_Check (Sel, Comp);
3180 Set_Etype (Sel, Etype (Comp));
3182 if Ekind (Comp) = E_Discriminant then
3183 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3185 ("cannot reference discriminant of Unchecked_Union",
3189 if Is_Generic_Type (Prefix_Type)
3191 Is_Generic_Type (Root_Type (Prefix_Type))
3193 Set_Original_Discriminant (Sel, Comp);
3197 -- Resolve the prefix early otherwise it is not possible to
3198 -- build the actual subtype of the component: it may need
3199 -- to duplicate this prefix and duplication is only allowed
3200 -- on fully resolved expressions.
3204 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3205 -- subtypes in a package specification.
3208 -- limited with Pkg;
3210 -- type Acc_Inc is access Pkg.T;
3212 -- N : Natural := X.all.Comp; -- ERROR, limited view
3213 -- end Pkg; -- Comp is not visible
3215 if Nkind (Name) = N_Explicit_Dereference
3216 and then From_With_Type (Etype (Prefix (Name)))
3217 and then not Is_Potentially_Use_Visible (Etype (Name))
3218 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3219 N_Package_Specification
3222 ("premature usage of incomplete}", Prefix (Name),
3223 Etype (Prefix (Name)));
3226 -- We never need an actual subtype for the case of a selection
3227 -- for a indexed component of a non-packed array, since in
3228 -- this case gigi generates all the checks and can find the
3229 -- necessary bounds information.
3231 -- We also do not need an actual subtype for the case of
3232 -- a first, last, length, or range attribute applied to a
3233 -- non-packed array, since gigi can again get the bounds in
3234 -- these cases (gigi cannot handle the packed case, since it
3235 -- has the bounds of the packed array type, not the original
3236 -- bounds of the type). However, if the prefix is itself a
3237 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3238 -- as a dynamic-sized temporary, so we do generate an actual
3239 -- subtype for this case.
3241 Parent_N := Parent (N);
3243 if not Is_Packed (Etype (Comp))
3245 ((Nkind (Parent_N) = N_Indexed_Component
3246 and then Nkind (Name) /= N_Selected_Component)
3248 (Nkind (Parent_N) = N_Attribute_Reference
3249 and then (Attribute_Name (Parent_N) = Name_First
3251 Attribute_Name (Parent_N) = Name_Last
3253 Attribute_Name (Parent_N) = Name_Length
3255 Attribute_Name (Parent_N) = Name_Range)))
3257 Set_Etype (N, Etype (Comp));
3259 -- If full analysis is not enabled, we do not generate an
3260 -- actual subtype, because in the absence of expansion
3261 -- reference to a formal of a protected type, for example,
3262 -- will not be properly transformed, and will lead to
3263 -- out-of-scope references in gigi.
3265 -- In all other cases, we currently build an actual subtype.
3266 -- It seems likely that many of these cases can be avoided,
3267 -- but right now, the front end makes direct references to the
3268 -- bounds (e.g. in generating a length check), and if we do
3269 -- not make an actual subtype, we end up getting a direct
3270 -- reference to a discriminant, which will not do.
3272 elsif Full_Analysis then
3274 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3275 Insert_Action (N, Act_Decl);
3277 if No (Act_Decl) then
3278 Set_Etype (N, Etype (Comp));
3281 -- Component type depends on discriminants. Enter the
3282 -- main attributes of the subtype.
3285 Subt : constant Entity_Id :=
3286 Defining_Identifier (Act_Decl);
3289 Set_Etype (Subt, Base_Type (Etype (Comp)));
3290 Set_Ekind (Subt, Ekind (Etype (Comp)));
3291 Set_Etype (N, Subt);
3295 -- If Full_Analysis not enabled, just set the Etype
3298 Set_Etype (N, Etype (Comp));
3304 -- If the prefix is a private extension, check only the visible
3305 -- components of the partial view. This must include the tag,
3306 -- which can appear in expanded code in a tag check.
3308 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3309 and then Chars (Selector_Name (N)) /= Name_uTag
3311 exit when Comp = Last_Entity (Type_To_Use);
3317 -- Ada 2005 (AI-252): The selected component can be interpreted as
3318 -- a prefixed view of a subprogram. Depending on the context, this is
3319 -- either a name that can appear in a renaming declaration, or part
3320 -- of an enclosing call given in prefix form.
3322 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3323 -- selected component should resolve to a name.
3325 if Ada_Version >= Ada_05
3326 and then Is_Tagged_Type (Prefix_Type)
3327 and then not Is_Concurrent_Type (Prefix_Type)
3329 if Nkind (Parent (N)) = N_Generic_Association
3330 or else Nkind (Parent (N)) = N_Requeue_Statement
3331 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3333 if Find_Primitive_Operation (N) then
3337 elsif Try_Object_Operation (N) then
3341 -- If the transformation fails, it will be necessary to redo the
3342 -- analysis with all errors enabled, to indicate candidate
3343 -- interpretations and reasons for each failure ???
3347 elsif Is_Private_Type (Prefix_Type) then
3349 -- Allow access only to discriminants of the type. If the type has
3350 -- no full view, gigi uses the parent type for the components, so we
3351 -- do the same here.
3353 if No (Full_View (Prefix_Type)) then
3354 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3355 Comp := First_Entity (Type_To_Use);
3358 while Present (Comp) loop
3359 if Chars (Comp) = Chars (Sel) then
3360 if Ekind (Comp) = E_Discriminant then
3361 Set_Entity_With_Style_Check (Sel, Comp);
3362 Generate_Reference (Comp, Sel);
3364 Set_Etype (Sel, Etype (Comp));
3365 Set_Etype (N, Etype (Comp));
3367 if Is_Generic_Type (Prefix_Type)
3368 or else Is_Generic_Type (Root_Type (Prefix_Type))
3370 Set_Original_Discriminant (Sel, Comp);
3373 -- Before declaring an error, check whether this is tagged
3374 -- private type and a call to a primitive operation.
3376 elsif Ada_Version >= Ada_05
3377 and then Is_Tagged_Type (Prefix_Type)
3378 and then Try_Object_Operation (N)
3384 ("invisible selector for }",
3385 N, First_Subtype (Prefix_Type));
3386 Set_Entity (Sel, Any_Id);
3387 Set_Etype (N, Any_Type);
3396 elsif Is_Concurrent_Type (Prefix_Type) then
3398 -- Find visible operation with given name. For a protected type,
3399 -- the possible candidates are discriminants, entries or protected
3400 -- procedures. For a task type, the set can only include entries or
3401 -- discriminants if the task type is not an enclosing scope. If it
3402 -- is an enclosing scope (e.g. in an inner task) then all entities
3403 -- are visible, but the prefix must denote the enclosing scope, i.e.
3404 -- can only be a direct name or an expanded name.
3406 Set_Etype (Sel, Any_Type);
3407 In_Scope := In_Open_Scopes (Prefix_Type);
3409 while Present (Comp) loop
3410 if Chars (Comp) = Chars (Sel) then
3411 if Is_Overloadable (Comp) then
3412 Add_One_Interp (Sel, Comp, Etype (Comp));
3414 -- If the prefix is tagged, the correct interpretation may
3415 -- lie in the primitive or class-wide operations of the
3416 -- type. Perform a simple conformance check to determine
3417 -- whether Try_Object_Operation should be invoked even if
3418 -- a visible entity is found.
3420 if Is_Tagged_Type (Prefix_Type)
3422 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3424 N_Indexed_Component)
3425 and then Has_Mode_Conformant_Spec (Comp)
3427 Has_Candidate := True;
3430 elsif Ekind (Comp) = E_Discriminant
3431 or else Ekind (Comp) = E_Entry_Family
3433 and then Is_Entity_Name (Name))
3435 Set_Entity_With_Style_Check (Sel, Comp);
3436 Generate_Reference (Comp, Sel);
3442 Set_Etype (Sel, Etype (Comp));
3443 Set_Etype (N, Etype (Comp));
3445 if Ekind (Comp) = E_Discriminant then
3446 Set_Original_Discriminant (Sel, Comp);
3449 -- For access type case, introduce explicit deference for more
3450 -- uniform treatment of entry calls.
3452 if Is_Access_Type (Etype (Name)) then
3453 Insert_Explicit_Dereference (Name);
3455 (Warn_On_Dereference, "?implicit dereference", N);
3461 exit when not In_Scope
3463 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3466 -- If there is no visible entity with the given name or none of the
3467 -- visible entities are plausible interpretations, check whether
3468 -- there is some other primitive operation with that name.
3470 if Ada_Version >= Ada_05
3471 and then Is_Tagged_Type (Prefix_Type)
3473 if (Etype (N) = Any_Type
3474 or else not Has_Candidate)
3475 and then Try_Object_Operation (N)
3479 -- If the context is not syntactically a procedure call, it
3480 -- may be a call to a primitive function declared outside of
3481 -- the synchronized type.
3483 -- If the context is a procedure call, there might still be
3484 -- an overloading between an entry and a primitive procedure
3485 -- declared outside of the synchronized type, called in prefix
3486 -- notation. This is harder to disambiguate because in one case
3487 -- the controlling formal is implicit ???
3489 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
3490 and then Nkind (Parent (N)) /= N_Indexed_Component
3491 and then Try_Object_Operation (N)
3497 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3502 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
3505 -- If N still has no type, the component is not defined in the prefix
3507 if Etype (N) = Any_Type then
3509 -- If the prefix is a single concurrent object, use its name in the
3510 -- error message, rather than that of its anonymous type.
3512 if Is_Concurrent_Type (Prefix_Type)
3513 and then Is_Internal_Name (Chars (Prefix_Type))
3514 and then not Is_Derived_Type (Prefix_Type)
3515 and then Is_Entity_Name (Name)
3518 Error_Msg_Node_2 := Entity (Name);
3519 Error_Msg_NE ("no selector& for&", N, Sel);
3521 Check_Misspelled_Selector (Type_To_Use, Sel);
3523 elsif Is_Generic_Type (Prefix_Type)
3524 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
3525 and then Prefix_Type /= Etype (Prefix_Type)
3526 and then Is_Record_Type (Etype (Prefix_Type))
3528 -- If this is a derived formal type, the parent may have
3529 -- different visibility at this point. Try for an inherited
3530 -- component before reporting an error.
3532 Set_Etype (Prefix (N), Etype (Prefix_Type));
3533 Analyze_Selected_Component (N);
3536 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
3537 and then Is_Generic_Actual_Type (Prefix_Type)
3538 and then Present (Full_View (Prefix_Type))
3540 -- Similarly, if this the actual for a formal derived type, the
3541 -- component inherited from the generic parent may not be visible
3542 -- in the actual, but the selected component is legal.
3549 First_Component (Generic_Parent_Type (Parent (Prefix_Type)));
3550 while Present (Comp) loop
3551 if Chars (Comp) = Chars (Sel) then
3552 Set_Entity_With_Style_Check (Sel, Comp);
3553 Set_Etype (Sel, Etype (Comp));
3554 Set_Etype (N, Etype (Comp));
3558 Next_Component (Comp);
3561 pragma Assert (Etype (N) /= Any_Type);
3565 if Ekind (Prefix_Type) = E_Record_Subtype then
3567 -- Check whether this is a component of the base type
3568 -- which is absent from a statically constrained subtype.
3569 -- This will raise constraint error at run-time, but is
3570 -- not a compile-time error. When the selector is illegal
3571 -- for base type as well fall through and generate a
3572 -- compilation error anyway.
3574 Comp := First_Component (Base_Type (Prefix_Type));
3575 while Present (Comp) loop
3576 if Chars (Comp) = Chars (Sel)
3577 and then Is_Visible_Component (Comp)
3579 Set_Entity_With_Style_Check (Sel, Comp);
3580 Generate_Reference (Comp, Sel);
3581 Set_Etype (Sel, Etype (Comp));
3582 Set_Etype (N, Etype (Comp));
3584 -- Emit appropriate message. Gigi will replace the
3585 -- node subsequently with the appropriate Raise.
3587 Apply_Compile_Time_Constraint_Error
3588 (N, "component not present in }?",
3589 CE_Discriminant_Check_Failed,
3590 Ent => Prefix_Type, Rep => False);
3591 Set_Raises_Constraint_Error (N);
3595 Next_Component (Comp);
3600 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3601 Error_Msg_NE ("no selector& for}", N, Sel);
3603 Check_Misspelled_Selector (Type_To_Use, Sel);
3606 Set_Entity (Sel, Any_Id);
3607 Set_Etype (Sel, Any_Type);
3609 end Analyze_Selected_Component;
3611 ---------------------------
3612 -- Analyze_Short_Circuit --
3613 ---------------------------
3615 procedure Analyze_Short_Circuit (N : Node_Id) is
3616 L : constant Node_Id := Left_Opnd (N);
3617 R : constant Node_Id := Right_Opnd (N);
3622 Analyze_Expression (L);
3623 Analyze_Expression (R);
3624 Set_Etype (N, Any_Type);
3626 if not Is_Overloaded (L) then
3627 if Root_Type (Etype (L)) = Standard_Boolean
3628 and then Has_Compatible_Type (R, Etype (L))
3630 Add_One_Interp (N, Etype (L), Etype (L));
3634 Get_First_Interp (L, Ind, It);
3635 while Present (It.Typ) loop
3636 if Root_Type (It.Typ) = Standard_Boolean
3637 and then Has_Compatible_Type (R, It.Typ)
3639 Add_One_Interp (N, It.Typ, It.Typ);
3642 Get_Next_Interp (Ind, It);
3646 -- Here we have failed to find an interpretation. Clearly we know that
3647 -- it is not the case that both operands can have an interpretation of
3648 -- Boolean, but this is by far the most likely intended interpretation.
3649 -- So we simply resolve both operands as Booleans, and at least one of
3650 -- these resolutions will generate an error message, and we do not need
3651 -- to give another error message on the short circuit operation itself.
3653 if Etype (N) = Any_Type then
3654 Resolve (L, Standard_Boolean);
3655 Resolve (R, Standard_Boolean);
3656 Set_Etype (N, Standard_Boolean);
3658 end Analyze_Short_Circuit;
3664 procedure Analyze_Slice (N : Node_Id) is
3665 P : constant Node_Id := Prefix (N);
3666 D : constant Node_Id := Discrete_Range (N);
3667 Array_Type : Entity_Id;
3669 procedure Analyze_Overloaded_Slice;
3670 -- If the prefix is overloaded, select those interpretations that
3671 -- yield a one-dimensional array type.
3673 ------------------------------
3674 -- Analyze_Overloaded_Slice --
3675 ------------------------------
3677 procedure Analyze_Overloaded_Slice is
3683 Set_Etype (N, Any_Type);
3685 Get_First_Interp (P, I, It);
3686 while Present (It.Nam) loop
3689 if Is_Access_Type (Typ) then
3690 Typ := Designated_Type (Typ);
3691 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3694 if Is_Array_Type (Typ)
3695 and then Number_Dimensions (Typ) = 1
3696 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
3698 Add_One_Interp (N, Typ, Typ);
3701 Get_Next_Interp (I, It);
3704 if Etype (N) = Any_Type then
3705 Error_Msg_N ("expect array type in prefix of slice", N);
3707 end Analyze_Overloaded_Slice;
3709 -- Start of processing for Analyze_Slice
3715 if Is_Overloaded (P) then
3716 Analyze_Overloaded_Slice;
3719 Array_Type := Etype (P);
3720 Set_Etype (N, Any_Type);
3722 if Is_Access_Type (Array_Type) then
3723 Array_Type := Designated_Type (Array_Type);
3724 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3727 if not Is_Array_Type (Array_Type) then
3728 Wrong_Type (P, Any_Array);
3730 elsif Number_Dimensions (Array_Type) > 1 then
3732 ("type is not one-dimensional array in slice prefix", N);
3735 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
3737 Wrong_Type (D, Etype (First_Index (Array_Type)));
3740 Set_Etype (N, Array_Type);
3745 -----------------------------
3746 -- Analyze_Type_Conversion --
3747 -----------------------------
3749 procedure Analyze_Type_Conversion (N : Node_Id) is
3750 Expr : constant Node_Id := Expression (N);
3754 -- If Conversion_OK is set, then the Etype is already set, and the
3755 -- only processing required is to analyze the expression. This is
3756 -- used to construct certain "illegal" conversions which are not
3757 -- allowed by Ada semantics, but can be handled OK by Gigi, see
3758 -- Sinfo for further details.
3760 if Conversion_OK (N) then
3765 -- Otherwise full type analysis is required, as well as some semantic
3766 -- checks to make sure the argument of the conversion is appropriate.
3768 Find_Type (Subtype_Mark (N));
3769 T := Entity (Subtype_Mark (N));
3771 Check_Fully_Declared (T, N);
3772 Analyze_Expression (Expr);
3773 Validate_Remote_Type_Type_Conversion (N);
3775 -- Only remaining step is validity checks on the argument. These
3776 -- are skipped if the conversion does not come from the source.
3778 if not Comes_From_Source (N) then
3781 -- If there was an error in a generic unit, no need to replicate the
3782 -- error message. Conversely, constant-folding in the generic may
3783 -- transform the argument of a conversion into a string literal, which
3784 -- is legal. Therefore the following tests are not performed in an
3787 elsif In_Instance then
3790 elsif Nkind (Expr) = N_Null then
3791 Error_Msg_N ("argument of conversion cannot be null", N);
3792 Error_Msg_N ("\use qualified expression instead", N);
3793 Set_Etype (N, Any_Type);
3795 elsif Nkind (Expr) = N_Aggregate then
3796 Error_Msg_N ("argument of conversion cannot be aggregate", N);
3797 Error_Msg_N ("\use qualified expression instead", N);
3799 elsif Nkind (Expr) = N_Allocator then
3800 Error_Msg_N ("argument of conversion cannot be an allocator", N);
3801 Error_Msg_N ("\use qualified expression instead", N);
3803 elsif Nkind (Expr) = N_String_Literal then
3804 Error_Msg_N ("argument of conversion cannot be string literal", N);
3805 Error_Msg_N ("\use qualified expression instead", N);
3807 elsif Nkind (Expr) = N_Character_Literal then
3808 if Ada_Version = Ada_83 then
3811 Error_Msg_N ("argument of conversion cannot be character literal",
3813 Error_Msg_N ("\use qualified expression instead", N);
3816 elsif Nkind (Expr) = N_Attribute_Reference
3818 (Attribute_Name (Expr) = Name_Access or else
3819 Attribute_Name (Expr) = Name_Unchecked_Access or else
3820 Attribute_Name (Expr) = Name_Unrestricted_Access)
3822 Error_Msg_N ("argument of conversion cannot be access", N);
3823 Error_Msg_N ("\use qualified expression instead", N);
3825 end Analyze_Type_Conversion;
3827 ----------------------
3828 -- Analyze_Unary_Op --
3829 ----------------------
3831 procedure Analyze_Unary_Op (N : Node_Id) is
3832 R : constant Node_Id := Right_Opnd (N);
3833 Op_Id : Entity_Id := Entity (N);
3836 Set_Etype (N, Any_Type);
3837 Candidate_Type := Empty;
3839 Analyze_Expression (R);
3841 if Present (Op_Id) then
3842 if Ekind (Op_Id) = E_Operator then
3843 Find_Unary_Types (R, Op_Id, N);
3845 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3849 Op_Id := Get_Name_Entity_Id (Chars (N));
3850 while Present (Op_Id) loop
3851 if Ekind (Op_Id) = E_Operator then
3852 if No (Next_Entity (First_Entity (Op_Id))) then
3853 Find_Unary_Types (R, Op_Id, N);
3856 elsif Is_Overloadable (Op_Id) then
3857 Analyze_User_Defined_Unary_Op (N, Op_Id);
3860 Op_Id := Homonym (Op_Id);
3865 end Analyze_Unary_Op;
3867 ----------------------------------
3868 -- Analyze_Unchecked_Expression --
3869 ----------------------------------
3871 procedure Analyze_Unchecked_Expression (N : Node_Id) is
3873 Analyze (Expression (N), Suppress => All_Checks);
3874 Set_Etype (N, Etype (Expression (N)));
3875 Save_Interps (Expression (N), N);
3876 end Analyze_Unchecked_Expression;
3878 ---------------------------------------
3879 -- Analyze_Unchecked_Type_Conversion --
3880 ---------------------------------------
3882 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
3884 Find_Type (Subtype_Mark (N));
3885 Analyze_Expression (Expression (N));
3886 Set_Etype (N, Entity (Subtype_Mark (N)));
3887 end Analyze_Unchecked_Type_Conversion;
3889 ------------------------------------
3890 -- Analyze_User_Defined_Binary_Op --
3891 ------------------------------------
3893 procedure Analyze_User_Defined_Binary_Op
3898 -- Only do analysis if the operator Comes_From_Source, since otherwise
3899 -- the operator was generated by the expander, and all such operators
3900 -- always refer to the operators in package Standard.
3902 if Comes_From_Source (N) then
3904 F1 : constant Entity_Id := First_Formal (Op_Id);
3905 F2 : constant Entity_Id := Next_Formal (F1);
3908 -- Verify that Op_Id is a visible binary function. Note that since
3909 -- we know Op_Id is overloaded, potentially use visible means use
3910 -- visible for sure (RM 9.4(11)).
3912 if Ekind (Op_Id) = E_Function
3913 and then Present (F2)
3914 and then (Is_Immediately_Visible (Op_Id)
3915 or else Is_Potentially_Use_Visible (Op_Id))
3916 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
3917 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
3919 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3921 if Debug_Flag_E then
3922 Write_Str ("user defined operator ");
3923 Write_Name (Chars (Op_Id));
3924 Write_Str (" on node ");
3925 Write_Int (Int (N));
3931 end Analyze_User_Defined_Binary_Op;
3933 -----------------------------------
3934 -- Analyze_User_Defined_Unary_Op --
3935 -----------------------------------
3937 procedure Analyze_User_Defined_Unary_Op
3942 -- Only do analysis if the operator Comes_From_Source, since otherwise
3943 -- the operator was generated by the expander, and all such operators
3944 -- always refer to the operators in package Standard.
3946 if Comes_From_Source (N) then
3948 F : constant Entity_Id := First_Formal (Op_Id);
3951 -- Verify that Op_Id is a visible unary function. Note that since
3952 -- we know Op_Id is overloaded, potentially use visible means use
3953 -- visible for sure (RM 9.4(11)).
3955 if Ekind (Op_Id) = E_Function
3956 and then No (Next_Formal (F))
3957 and then (Is_Immediately_Visible (Op_Id)
3958 or else Is_Potentially_Use_Visible (Op_Id))
3959 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
3961 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3965 end Analyze_User_Defined_Unary_Op;
3967 ---------------------------
3968 -- Check_Arithmetic_Pair --
3969 ---------------------------
3971 procedure Check_Arithmetic_Pair
3972 (T1, T2 : Entity_Id;
3976 Op_Name : constant Name_Id := Chars (Op_Id);
3978 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
3979 -- Check whether the fixed-point type Typ has a user-defined operator
3980 -- (multiplication or division) that should hide the corresponding
3981 -- predefined operator. Used to implement Ada 2005 AI-264, to make
3982 -- such operators more visible and therefore useful.
3984 -- If the name of the operation is an expanded name with prefix
3985 -- Standard, the predefined universal fixed operator is available,
3986 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
3988 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
3989 -- Get specific type (i.e. non-universal type if there is one)
3995 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
3996 Bas : constant Entity_Id := Base_Type (Typ);
4002 -- If the universal_fixed operation is given explicitly the rule
4003 -- concerning primitive operations of the type do not apply.
4005 if Nkind (N) = N_Function_Call
4006 and then Nkind (Name (N)) = N_Expanded_Name
4007 and then Entity (Prefix (Name (N))) = Standard_Standard
4012 -- The operation is treated as primitive if it is declared in the
4013 -- same scope as the type, and therefore on the same entity chain.
4015 Ent := Next_Entity (Typ);
4016 while Present (Ent) loop
4017 if Chars (Ent) = Chars (Op) then
4018 F1 := First_Formal (Ent);
4019 F2 := Next_Formal (F1);
4021 -- The operation counts as primitive if either operand or
4022 -- result are of the given base type, and both operands are
4023 -- fixed point types.
4025 if (Base_Type (Etype (F1)) = Bas
4026 and then Is_Fixed_Point_Type (Etype (F2)))
4029 (Base_Type (Etype (F2)) = Bas
4030 and then Is_Fixed_Point_Type (Etype (F1)))
4033 (Base_Type (Etype (Ent)) = Bas
4034 and then Is_Fixed_Point_Type (Etype (F1))
4035 and then Is_Fixed_Point_Type (Etype (F2)))
4051 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4053 if T1 = Universal_Integer or else T1 = Universal_Real then
4054 return Base_Type (T2);
4056 return Base_Type (T1);
4060 -- Start of processing for Check_Arithmetic_Pair
4063 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4065 if Is_Numeric_Type (T1)
4066 and then Is_Numeric_Type (T2)
4067 and then (Covers (T1 => T1, T2 => T2)
4069 Covers (T1 => T2, T2 => T1))
4071 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4074 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4076 if Is_Fixed_Point_Type (T1)
4077 and then (Is_Fixed_Point_Type (T2)
4078 or else T2 = Universal_Real)
4080 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4081 -- and no further processing is required (this is the case of an
4082 -- operator constructed by Exp_Fixd for a fixed point operation)
4083 -- Otherwise add one interpretation with universal fixed result
4084 -- If the operator is given in functional notation, it comes
4085 -- from source and Fixed_As_Integer cannot apply.
4087 if (Nkind (N) not in N_Op
4088 or else not Treat_Fixed_As_Integer (N))
4090 (not Has_Fixed_Op (T1, Op_Id)
4091 or else Nkind (Parent (N)) = N_Type_Conversion)
4093 Add_One_Interp (N, Op_Id, Universal_Fixed);
4096 elsif Is_Fixed_Point_Type (T2)
4097 and then (Nkind (N) not in N_Op
4098 or else not Treat_Fixed_As_Integer (N))
4099 and then T1 = Universal_Real
4101 (not Has_Fixed_Op (T1, Op_Id)
4102 or else Nkind (Parent (N)) = N_Type_Conversion)
4104 Add_One_Interp (N, Op_Id, Universal_Fixed);
4106 elsif Is_Numeric_Type (T1)
4107 and then Is_Numeric_Type (T2)
4108 and then (Covers (T1 => T1, T2 => T2)
4110 Covers (T1 => T2, T2 => T1))
4112 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4114 elsif Is_Fixed_Point_Type (T1)
4115 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4116 or else T2 = Universal_Integer)
4118 Add_One_Interp (N, Op_Id, T1);
4120 elsif T2 = Universal_Real
4121 and then Base_Type (T1) = Base_Type (Standard_Integer)
4122 and then Op_Name = Name_Op_Multiply
4124 Add_One_Interp (N, Op_Id, Any_Fixed);
4126 elsif T1 = Universal_Real
4127 and then Base_Type (T2) = Base_Type (Standard_Integer)
4129 Add_One_Interp (N, Op_Id, Any_Fixed);
4131 elsif Is_Fixed_Point_Type (T2)
4132 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4133 or else T1 = Universal_Integer)
4134 and then Op_Name = Name_Op_Multiply
4136 Add_One_Interp (N, Op_Id, T2);
4138 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4139 Add_One_Interp (N, Op_Id, T1);
4141 elsif T2 = Universal_Real
4142 and then T1 = Universal_Integer
4143 and then Op_Name = Name_Op_Multiply
4145 Add_One_Interp (N, Op_Id, T2);
4148 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4150 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4151 -- set does not require any special processing, since the Etype is
4152 -- already set (case of operation constructed by Exp_Fixed).
4154 if Is_Integer_Type (T1)
4155 and then (Covers (T1 => T1, T2 => T2)
4157 Covers (T1 => T2, T2 => T1))
4159 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4162 elsif Op_Name = Name_Op_Expon then
4163 if Is_Numeric_Type (T1)
4164 and then not Is_Fixed_Point_Type (T1)
4165 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4166 or else T2 = Universal_Integer)
4168 Add_One_Interp (N, Op_Id, Base_Type (T1));
4171 else pragma Assert (Nkind (N) in N_Op_Shift);
4173 -- If not one of the predefined operators, the node may be one
4174 -- of the intrinsic functions. Its kind is always specific, and
4175 -- we can use it directly, rather than the name of the operation.
4177 if Is_Integer_Type (T1)
4178 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4179 or else T2 = Universal_Integer)
4181 Add_One_Interp (N, Op_Id, Base_Type (T1));
4184 end Check_Arithmetic_Pair;
4186 -------------------------------
4187 -- Check_Misspelled_Selector --
4188 -------------------------------
4190 procedure Check_Misspelled_Selector
4191 (Prefix : Entity_Id;
4194 Max_Suggestions : constant := 2;
4195 Nr_Of_Suggestions : Natural := 0;
4197 Suggestion_1 : Entity_Id := Empty;
4198 Suggestion_2 : Entity_Id := Empty;
4203 -- All the components of the prefix of selector Sel are matched
4204 -- against Sel and a count is maintained of possible misspellings.
4205 -- When at the end of the analysis there are one or two (not more!)
4206 -- possible misspellings, these misspellings will be suggested as
4207 -- possible correction.
4209 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4211 -- Concurrent types should be handled as well ???
4216 Comp := First_Entity (Prefix);
4217 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4218 if Is_Visible_Component (Comp) then
4219 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4220 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4222 case Nr_Of_Suggestions is
4223 when 1 => Suggestion_1 := Comp;
4224 when 2 => Suggestion_2 := Comp;
4225 when others => exit;
4230 Comp := Next_Entity (Comp);
4233 -- Report at most two suggestions
4235 if Nr_Of_Suggestions = 1 then
4237 ("\possible misspelling of&", Sel, Suggestion_1);
4239 elsif Nr_Of_Suggestions = 2 then
4240 Error_Msg_Node_2 := Suggestion_2;
4242 ("\possible misspelling of& or&", Sel, Suggestion_1);
4244 end Check_Misspelled_Selector;
4246 ----------------------
4247 -- Defined_In_Scope --
4248 ----------------------
4250 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4252 S1 : constant Entity_Id := Scope (Base_Type (T));
4255 or else (S1 = System_Aux_Id and then S = Scope (S1));
4256 end Defined_In_Scope;
4262 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4268 Void_Interp_Seen : Boolean := False;
4271 pragma Warnings (Off, Boolean);
4274 if Ada_Version >= Ada_05 then
4275 Actual := First_Actual (N);
4276 while Present (Actual) loop
4278 -- Ada 2005 (AI-50217): Post an error in case of premature
4279 -- usage of an entity from the limited view.
4281 if not Analyzed (Etype (Actual))
4282 and then From_With_Type (Etype (Actual))
4284 Error_Msg_Qual_Level := 1;
4286 ("missing with_clause for scope of imported type&",
4287 Actual, Etype (Actual));
4288 Error_Msg_Qual_Level := 0;
4291 Next_Actual (Actual);
4295 -- Analyze each candidate call again, with full error reporting
4299 ("no candidate interpretations match the actuals:!", Nam);
4300 Err_Mode := All_Errors_Mode;
4301 All_Errors_Mode := True;
4303 -- If this is a call to an operation of a concurrent type,
4304 -- the failed interpretations have been removed from the
4305 -- name. Recover them to provide full diagnostics.
4307 if Nkind (Parent (Nam)) = N_Selected_Component then
4308 Set_Entity (Nam, Empty);
4309 New_Nam := New_Copy_Tree (Parent (Nam));
4310 Set_Is_Overloaded (New_Nam, False);
4311 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4312 Set_Parent (New_Nam, Parent (Parent (Nam)));
4313 Analyze_Selected_Component (New_Nam);
4314 Get_First_Interp (Selector_Name (New_Nam), X, It);
4316 Get_First_Interp (Nam, X, It);
4319 while Present (It.Nam) loop
4320 if Etype (It.Nam) = Standard_Void_Type then
4321 Void_Interp_Seen := True;
4324 Analyze_One_Call (N, It.Nam, True, Success);
4325 Get_Next_Interp (X, It);
4328 if Nkind (N) = N_Function_Call then
4329 Get_First_Interp (Nam, X, It);
4330 while Present (It.Nam) loop
4331 if Ekind (It.Nam) = E_Function
4332 or else Ekind (It.Nam) = E_Operator
4336 Get_Next_Interp (X, It);
4340 -- If all interpretations are procedures, this deserves a
4341 -- more precise message. Ditto if this appears as the prefix
4342 -- of a selected component, which may be a lexical error.
4345 ("\context requires function call, found procedure name", Nam);
4347 if Nkind (Parent (N)) = N_Selected_Component
4348 and then N = Prefix (Parent (N))
4351 "\period should probably be semicolon", Parent (N));
4354 elsif Nkind (N) = N_Procedure_Call_Statement
4355 and then not Void_Interp_Seen
4358 "\function name found in procedure call", Nam);
4361 All_Errors_Mode := Err_Mode;
4364 ---------------------------
4365 -- Find_Arithmetic_Types --
4366 ---------------------------
4368 procedure Find_Arithmetic_Types
4373 Index1 : Interp_Index;
4374 Index2 : Interp_Index;
4378 procedure Check_Right_Argument (T : Entity_Id);
4379 -- Check right operand of operator
4381 --------------------------
4382 -- Check_Right_Argument --
4383 --------------------------
4385 procedure Check_Right_Argument (T : Entity_Id) is
4387 if not Is_Overloaded (R) then
4388 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4390 Get_First_Interp (R, Index2, It2);
4391 while Present (It2.Typ) loop
4392 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4393 Get_Next_Interp (Index2, It2);
4396 end Check_Right_Argument;
4398 -- Start processing for Find_Arithmetic_Types
4401 if not Is_Overloaded (L) then
4402 Check_Right_Argument (Etype (L));
4405 Get_First_Interp (L, Index1, It1);
4406 while Present (It1.Typ) loop
4407 Check_Right_Argument (It1.Typ);
4408 Get_Next_Interp (Index1, It1);
4412 end Find_Arithmetic_Types;
4414 ------------------------
4415 -- Find_Boolean_Types --
4416 ------------------------
4418 procedure Find_Boolean_Types
4423 Index : Interp_Index;
4426 procedure Check_Numeric_Argument (T : Entity_Id);
4427 -- Special case for logical operations one of whose operands is an
4428 -- integer literal. If both are literal the result is any modular type.
4430 ----------------------------
4431 -- Check_Numeric_Argument --
4432 ----------------------------
4434 procedure Check_Numeric_Argument (T : Entity_Id) is
4436 if T = Universal_Integer then
4437 Add_One_Interp (N, Op_Id, Any_Modular);
4439 elsif Is_Modular_Integer_Type (T) then
4440 Add_One_Interp (N, Op_Id, T);
4442 end Check_Numeric_Argument;
4444 -- Start of processing for Find_Boolean_Types
4447 if not Is_Overloaded (L) then
4448 if Etype (L) = Universal_Integer
4449 or else Etype (L) = Any_Modular
4451 if not Is_Overloaded (R) then
4452 Check_Numeric_Argument (Etype (R));
4455 Get_First_Interp (R, Index, It);
4456 while Present (It.Typ) loop
4457 Check_Numeric_Argument (It.Typ);
4458 Get_Next_Interp (Index, It);
4462 -- If operands are aggregates, we must assume that they may be
4463 -- boolean arrays, and leave disambiguation for the second pass.
4464 -- If only one is an aggregate, verify that the other one has an
4465 -- interpretation as a boolean array
4467 elsif Nkind (L) = N_Aggregate then
4468 if Nkind (R) = N_Aggregate then
4469 Add_One_Interp (N, Op_Id, Etype (L));
4471 elsif not Is_Overloaded (R) then
4472 if Valid_Boolean_Arg (Etype (R)) then
4473 Add_One_Interp (N, Op_Id, Etype (R));
4477 Get_First_Interp (R, Index, It);
4478 while Present (It.Typ) loop
4479 if Valid_Boolean_Arg (It.Typ) then
4480 Add_One_Interp (N, Op_Id, It.Typ);
4483 Get_Next_Interp (Index, It);
4487 elsif Valid_Boolean_Arg (Etype (L))
4488 and then Has_Compatible_Type (R, Etype (L))
4490 Add_One_Interp (N, Op_Id, Etype (L));
4494 Get_First_Interp (L, Index, It);
4495 while Present (It.Typ) loop
4496 if Valid_Boolean_Arg (It.Typ)
4497 and then Has_Compatible_Type (R, It.Typ)
4499 Add_One_Interp (N, Op_Id, It.Typ);
4502 Get_Next_Interp (Index, It);
4505 end Find_Boolean_Types;
4507 ---------------------------
4508 -- Find_Comparison_Types --
4509 ---------------------------
4511 procedure Find_Comparison_Types
4516 Index : Interp_Index;
4518 Found : Boolean := False;
4521 Scop : Entity_Id := Empty;
4523 procedure Try_One_Interp (T1 : Entity_Id);
4524 -- Routine to try one proposed interpretation. Note that the context
4525 -- of the operator plays no role in resolving the arguments, so that
4526 -- if there is more than one interpretation of the operands that is
4527 -- compatible with comparison, the operation is ambiguous.
4529 --------------------
4530 -- Try_One_Interp --
4531 --------------------
4533 procedure Try_One_Interp (T1 : Entity_Id) is
4536 -- If the operator is an expanded name, then the type of the operand
4537 -- must be defined in the corresponding scope. If the type is
4538 -- universal, the context will impose the correct type.
4541 and then not Defined_In_Scope (T1, Scop)
4542 and then T1 /= Universal_Integer
4543 and then T1 /= Universal_Real
4544 and then T1 /= Any_String
4545 and then T1 /= Any_Composite
4550 if Valid_Comparison_Arg (T1)
4551 and then Has_Compatible_Type (R, T1)
4554 and then Base_Type (T1) /= Base_Type (T_F)
4556 It := Disambiguate (L, I_F, Index, Any_Type);
4558 if It = No_Interp then
4559 Ambiguous_Operands (N);
4560 Set_Etype (L, Any_Type);
4574 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4579 -- Start processing for Find_Comparison_Types
4582 -- If left operand is aggregate, the right operand has to
4583 -- provide a usable type for it.
4585 if Nkind (L) = N_Aggregate
4586 and then Nkind (R) /= N_Aggregate
4588 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4592 if Nkind (N) = N_Function_Call
4593 and then Nkind (Name (N)) = N_Expanded_Name
4595 Scop := Entity (Prefix (Name (N)));
4597 -- The prefix may be a package renaming, and the subsequent test
4598 -- requires the original package.
4600 if Ekind (Scop) = E_Package
4601 and then Present (Renamed_Entity (Scop))
4603 Scop := Renamed_Entity (Scop);
4604 Set_Entity (Prefix (Name (N)), Scop);
4608 if not Is_Overloaded (L) then
4609 Try_One_Interp (Etype (L));
4612 Get_First_Interp (L, Index, It);
4613 while Present (It.Typ) loop
4614 Try_One_Interp (It.Typ);
4615 Get_Next_Interp (Index, It);
4618 end Find_Comparison_Types;
4620 ----------------------------------------
4621 -- Find_Non_Universal_Interpretations --
4622 ----------------------------------------
4624 procedure Find_Non_Universal_Interpretations
4630 Index : Interp_Index;
4634 if T1 = Universal_Integer
4635 or else T1 = Universal_Real
4637 if not Is_Overloaded (R) then
4639 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
4641 Get_First_Interp (R, Index, It);
4642 while Present (It.Typ) loop
4643 if Covers (It.Typ, T1) then
4645 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
4648 Get_Next_Interp (Index, It);
4652 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
4654 end Find_Non_Universal_Interpretations;
4656 ------------------------------
4657 -- Find_Concatenation_Types --
4658 ------------------------------
4660 procedure Find_Concatenation_Types
4665 Op_Type : constant Entity_Id := Etype (Op_Id);
4668 if Is_Array_Type (Op_Type)
4669 and then not Is_Limited_Type (Op_Type)
4671 and then (Has_Compatible_Type (L, Op_Type)
4673 Has_Compatible_Type (L, Component_Type (Op_Type)))
4675 and then (Has_Compatible_Type (R, Op_Type)
4677 Has_Compatible_Type (R, Component_Type (Op_Type)))
4679 Add_One_Interp (N, Op_Id, Op_Type);
4681 end Find_Concatenation_Types;
4683 -------------------------
4684 -- Find_Equality_Types --
4685 -------------------------
4687 procedure Find_Equality_Types
4692 Index : Interp_Index;
4694 Found : Boolean := False;
4697 Scop : Entity_Id := Empty;
4699 procedure Try_One_Interp (T1 : Entity_Id);
4700 -- The context of the operator plays no role in resolving the
4701 -- arguments, so that if there is more than one interpretation
4702 -- of the operands that is compatible with equality, the construct
4703 -- is ambiguous and an error can be emitted now, after trying to
4704 -- disambiguate, i.e. applying preference rules.
4706 --------------------
4707 -- Try_One_Interp --
4708 --------------------
4710 procedure Try_One_Interp (T1 : Entity_Id) is
4712 -- If the operator is an expanded name, then the type of the operand
4713 -- must be defined in the corresponding scope. If the type is
4714 -- universal, the context will impose the correct type. An anonymous
4715 -- type for a 'Access reference is also universal in this sense, as
4716 -- the actual type is obtained from context.
4717 -- In Ada 2005, the equality operator for anonymous access types
4718 -- is declared in Standard, and preference rules apply to it.
4720 if Present (Scop) then
4721 if Defined_In_Scope (T1, Scop)
4722 or else T1 = Universal_Integer
4723 or else T1 = Universal_Real
4724 or else T1 = Any_Access
4725 or else T1 = Any_String
4726 or else T1 = Any_Composite
4727 or else (Ekind (T1) = E_Access_Subprogram_Type
4728 and then not Comes_From_Source (T1))
4732 elsif Ekind (T1) = E_Anonymous_Access_Type
4733 and then Scop = Standard_Standard
4738 -- The scope does not contain an operator for the type
4744 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
4745 -- Do not allow anonymous access types in equality operators.
4747 if Ada_Version < Ada_05
4748 and then Ekind (T1) = E_Anonymous_Access_Type
4753 if T1 /= Standard_Void_Type
4754 and then not Is_Limited_Type (T1)
4755 and then not Is_Limited_Composite (T1)
4756 and then Has_Compatible_Type (R, T1)
4759 and then Base_Type (T1) /= Base_Type (T_F)
4761 It := Disambiguate (L, I_F, Index, Any_Type);
4763 if It = No_Interp then
4764 Ambiguous_Operands (N);
4765 Set_Etype (L, Any_Type);
4778 if not Analyzed (L) then
4782 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4784 -- Case of operator was not visible, Etype still set to Any_Type
4786 if Etype (N) = Any_Type then
4790 elsif Scop = Standard_Standard
4791 and then Ekind (T1) = E_Anonymous_Access_Type
4797 -- Start of processing for Find_Equality_Types
4800 -- If left operand is aggregate, the right operand has to
4801 -- provide a usable type for it.
4803 if Nkind (L) = N_Aggregate
4804 and then Nkind (R) /= N_Aggregate
4806 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
4810 if Nkind (N) = N_Function_Call
4811 and then Nkind (Name (N)) = N_Expanded_Name
4813 Scop := Entity (Prefix (Name (N)));
4815 -- The prefix may be a package renaming, and the subsequent test
4816 -- requires the original package.
4818 if Ekind (Scop) = E_Package
4819 and then Present (Renamed_Entity (Scop))
4821 Scop := Renamed_Entity (Scop);
4822 Set_Entity (Prefix (Name (N)), Scop);
4826 if not Is_Overloaded (L) then
4827 Try_One_Interp (Etype (L));
4830 Get_First_Interp (L, Index, It);
4831 while Present (It.Typ) loop
4832 Try_One_Interp (It.Typ);
4833 Get_Next_Interp (Index, It);
4836 end Find_Equality_Types;
4838 -------------------------
4839 -- Find_Negation_Types --
4840 -------------------------
4842 procedure Find_Negation_Types
4847 Index : Interp_Index;
4851 if not Is_Overloaded (R) then
4852 if Etype (R) = Universal_Integer then
4853 Add_One_Interp (N, Op_Id, Any_Modular);
4854 elsif Valid_Boolean_Arg (Etype (R)) then
4855 Add_One_Interp (N, Op_Id, Etype (R));
4859 Get_First_Interp (R, Index, It);
4860 while Present (It.Typ) loop
4861 if Valid_Boolean_Arg (It.Typ) then
4862 Add_One_Interp (N, Op_Id, It.Typ);
4865 Get_Next_Interp (Index, It);
4868 end Find_Negation_Types;
4870 ------------------------------
4871 -- Find_Primitive_Operation --
4872 ------------------------------
4874 function Find_Primitive_Operation (N : Node_Id) return Boolean is
4875 Obj : constant Node_Id := Prefix (N);
4876 Op : constant Node_Id := Selector_Name (N);
4883 Set_Etype (Op, Any_Type);
4885 if Is_Access_Type (Etype (Obj)) then
4886 Typ := Designated_Type (Etype (Obj));
4891 if Is_Class_Wide_Type (Typ) then
4892 Typ := Root_Type (Typ);
4895 Prims := Primitive_Operations (Typ);
4897 Prim := First_Elmt (Prims);
4898 while Present (Prim) loop
4899 if Chars (Node (Prim)) = Chars (Op) then
4900 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
4901 Set_Etype (N, Etype (Node (Prim)));
4907 -- Now look for class-wide operations of the type or any of its
4908 -- ancestors by iterating over the homonyms of the selector.
4911 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
4915 Hom := Current_Entity (Op);
4916 while Present (Hom) loop
4917 if (Ekind (Hom) = E_Procedure
4919 Ekind (Hom) = E_Function)
4920 and then Scope (Hom) = Scope (Typ)
4921 and then Present (First_Formal (Hom))
4923 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
4925 (Is_Access_Type (Etype (First_Formal (Hom)))
4927 Ekind (Etype (First_Formal (Hom))) =
4928 E_Anonymous_Access_Type
4931 (Designated_Type (Etype (First_Formal (Hom)))) =
4934 Add_One_Interp (Op, Hom, Etype (Hom));
4935 Set_Etype (N, Etype (Hom));
4938 Hom := Homonym (Hom);
4942 return Etype (Op) /= Any_Type;
4943 end Find_Primitive_Operation;
4945 ----------------------
4946 -- Find_Unary_Types --
4947 ----------------------
4949 procedure Find_Unary_Types
4954 Index : Interp_Index;
4958 if not Is_Overloaded (R) then
4959 if Is_Numeric_Type (Etype (R)) then
4960 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
4964 Get_First_Interp (R, Index, It);
4965 while Present (It.Typ) loop
4966 if Is_Numeric_Type (It.Typ) then
4967 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
4970 Get_Next_Interp (Index, It);
4973 end Find_Unary_Types;
4979 function Junk_Operand (N : Node_Id) return Boolean is
4983 if Error_Posted (N) then
4987 -- Get entity to be tested
4989 if Is_Entity_Name (N)
4990 and then Present (Entity (N))
4994 -- An odd case, a procedure name gets converted to a very peculiar
4995 -- function call, and here is where we detect this happening.
4997 elsif Nkind (N) = N_Function_Call
4998 and then Is_Entity_Name (Name (N))
4999 and then Present (Entity (Name (N)))
5003 -- Another odd case, there are at least some cases of selected
5004 -- components where the selected component is not marked as having
5005 -- an entity, even though the selector does have an entity
5007 elsif Nkind (N) = N_Selected_Component
5008 and then Present (Entity (Selector_Name (N)))
5010 Enode := Selector_Name (N);
5016 -- Now test the entity we got to see if it is a bad case
5018 case Ekind (Entity (Enode)) is
5022 ("package name cannot be used as operand", Enode);
5024 when Generic_Unit_Kind =>
5026 ("generic unit name cannot be used as operand", Enode);
5030 ("subtype name cannot be used as operand", Enode);
5034 ("entry name cannot be used as operand", Enode);
5038 ("procedure name cannot be used as operand", Enode);
5042 ("exception name cannot be used as operand", Enode);
5044 when E_Block | E_Label | E_Loop =>
5046 ("label name cannot be used as operand", Enode);
5056 --------------------
5057 -- Operator_Check --
5058 --------------------
5060 procedure Operator_Check (N : Node_Id) is
5062 Remove_Abstract_Operations (N);
5064 -- Test for case of no interpretation found for operator
5066 if Etype (N) = Any_Type then
5070 Op_Id : Entity_Id := Empty;
5073 R := Right_Opnd (N);
5075 if Nkind (N) in N_Binary_Op then
5081 -- If either operand has no type, then don't complain further,
5082 -- since this simply means that we have a propagated error.
5085 or else Etype (R) = Any_Type
5086 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5090 -- We explicitly check for the case of concatenation of component
5091 -- with component to avoid reporting spurious matching array types
5092 -- that might happen to be lurking in distant packages (such as
5093 -- run-time packages). This also prevents inconsistencies in the
5094 -- messages for certain ACVC B tests, which can vary depending on
5095 -- types declared in run-time interfaces. Another improvement when
5096 -- aggregates are present is to look for a well-typed operand.
5098 elsif Present (Candidate_Type)
5099 and then (Nkind (N) /= N_Op_Concat
5100 or else Is_Array_Type (Etype (L))
5101 or else Is_Array_Type (Etype (R)))
5104 if Nkind (N) = N_Op_Concat then
5105 if Etype (L) /= Any_Composite
5106 and then Is_Array_Type (Etype (L))
5108 Candidate_Type := Etype (L);
5110 elsif Etype (R) /= Any_Composite
5111 and then Is_Array_Type (Etype (R))
5113 Candidate_Type := Etype (R);
5118 ("operator for} is not directly visible!",
5119 N, First_Subtype (Candidate_Type));
5120 Error_Msg_N ("use clause would make operation legal!", N);
5123 -- If either operand is a junk operand (e.g. package name), then
5124 -- post appropriate error messages, but do not complain further.
5126 -- Note that the use of OR in this test instead of OR ELSE is
5127 -- quite deliberate, we may as well check both operands in the
5128 -- binary operator case.
5130 elsif Junk_Operand (R)
5131 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5135 -- If we have a logical operator, one of whose operands is
5136 -- Boolean, then we know that the other operand cannot resolve to
5137 -- Boolean (since we got no interpretations), but in that case we
5138 -- pretty much know that the other operand should be Boolean, so
5139 -- resolve it that way (generating an error)
5141 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5142 if Etype (L) = Standard_Boolean then
5143 Resolve (R, Standard_Boolean);
5145 elsif Etype (R) = Standard_Boolean then
5146 Resolve (L, Standard_Boolean);
5150 -- For an arithmetic operator or comparison operator, if one
5151 -- of the operands is numeric, then we know the other operand
5152 -- is not the same numeric type. If it is a non-numeric type,
5153 -- then probably it is intended to match the other operand.
5155 elsif Nkind_In (N, N_Op_Add,
5161 Nkind_In (N, N_Op_Lt,
5167 if Is_Numeric_Type (Etype (L))
5168 and then not Is_Numeric_Type (Etype (R))
5170 Resolve (R, Etype (L));
5173 elsif Is_Numeric_Type (Etype (R))
5174 and then not Is_Numeric_Type (Etype (L))
5176 Resolve (L, Etype (R));
5180 -- Comparisons on A'Access are common enough to deserve a
5183 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5184 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5185 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5188 ("two access attributes cannot be compared directly", N);
5190 ("\use qualified expression for one of the operands",
5194 -- Another one for C programmers
5196 elsif Nkind (N) = N_Op_Concat
5197 and then Valid_Boolean_Arg (Etype (L))
5198 and then Valid_Boolean_Arg (Etype (R))
5200 Error_Msg_N ("invalid operands for concatenation", N);
5201 Error_Msg_N ("\maybe AND was meant", N);
5204 -- A special case for comparison of access parameter with null
5206 elsif Nkind (N) = N_Op_Eq
5207 and then Is_Entity_Name (L)
5208 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5209 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5211 and then Nkind (R) = N_Null
5213 Error_Msg_N ("access parameter is not allowed to be null", L);
5214 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5218 -- If we fall through then just give general message. Note that in
5219 -- the following messages, if the operand is overloaded we choose
5220 -- an arbitrary type to complain about, but that is probably more
5221 -- useful than not giving a type at all.
5223 if Nkind (N) in N_Unary_Op then
5224 Error_Msg_Node_2 := Etype (R);
5225 Error_Msg_N ("operator& not defined for}", N);
5229 if Nkind (N) in N_Binary_Op then
5230 if not Is_Overloaded (L)
5231 and then not Is_Overloaded (R)
5232 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5234 Error_Msg_Node_2 := First_Subtype (Etype (R));
5235 Error_Msg_N ("there is no applicable operator& for}", N);
5238 -- Another attempt to find a fix: one of the candidate
5239 -- interpretations may not be use-visible. This has
5240 -- already been checked for predefined operators, so
5241 -- we examine only user-defined functions.
5243 Op_Id := Get_Name_Entity_Id (Chars (N));
5245 while Present (Op_Id) loop
5246 if Ekind (Op_Id) /= E_Operator
5247 and then Is_Overloadable (Op_Id)
5249 if not Is_Immediately_Visible (Op_Id)
5250 and then not In_Use (Scope (Op_Id))
5251 and then not Is_Abstract_Subprogram (Op_Id)
5252 and then not Is_Hidden (Op_Id)
5253 and then Ekind (Scope (Op_Id)) = E_Package
5256 (L, Etype (First_Formal (Op_Id)))
5258 (Next_Formal (First_Formal (Op_Id)))
5262 Etype (Next_Formal (First_Formal (Op_Id))))
5265 ("No legal interpretation for operator&", N);
5267 ("\use clause on& would make operation legal",
5273 Op_Id := Homonym (Op_Id);
5277 Error_Msg_N ("invalid operand types for operator&", N);
5279 if Nkind (N) /= N_Op_Concat then
5280 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5281 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5291 -----------------------------------------
5292 -- Process_Implicit_Dereference_Prefix --
5293 -----------------------------------------
5295 function Process_Implicit_Dereference_Prefix
5297 P : Entity_Id) return Entity_Id
5300 Typ : constant Entity_Id := Designated_Type (Etype (P));
5304 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5306 -- We create a dummy reference to E to ensure that the reference
5307 -- is not considered as part of an assignment (an implicit
5308 -- dereference can never assign to its prefix). The Comes_From_Source
5309 -- attribute needs to be propagated for accurate warnings.
5311 Ref := New_Reference_To (E, Sloc (P));
5312 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5313 Generate_Reference (E, Ref);
5316 -- An implicit dereference is a legal occurrence of an
5317 -- incomplete type imported through a limited_with clause,
5318 -- if the full view is visible.
5320 if From_With_Type (Typ)
5321 and then not From_With_Type (Scope (Typ))
5323 (Is_Immediately_Visible (Scope (Typ))
5325 (Is_Child_Unit (Scope (Typ))
5326 and then Is_Visible_Child_Unit (Scope (Typ))))
5328 return Available_View (Typ);
5333 end Process_Implicit_Dereference_Prefix;
5335 --------------------------------
5336 -- Remove_Abstract_Operations --
5337 --------------------------------
5339 procedure Remove_Abstract_Operations (N : Node_Id) is
5340 Abstract_Op : Entity_Id := Empty;
5341 Address_Kludge : Boolean := False;
5345 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5346 -- activate this if either extensions are enabled, or if the abstract
5347 -- operation in question comes from a predefined file. This latter test
5348 -- allows us to use abstract to make operations invisible to users. In
5349 -- particular, if type Address is non-private and abstract subprograms
5350 -- are used to hide its operators, they will be truly hidden.
5352 type Operand_Position is (First_Op, Second_Op);
5353 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5355 procedure Remove_Address_Interpretations (Op : Operand_Position);
5356 -- Ambiguities may arise when the operands are literal and the address
5357 -- operations in s-auxdec are visible. In that case, remove the
5358 -- interpretation of a literal as Address, to retain the semantics of
5359 -- Address as a private type.
5361 ------------------------------------
5362 -- Remove_Address_Interpretations --
5363 ------------------------------------
5365 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5369 if Is_Overloaded (N) then
5370 Get_First_Interp (N, I, It);
5371 while Present (It.Nam) loop
5372 Formal := First_Entity (It.Nam);
5374 if Op = Second_Op then
5375 Formal := Next_Entity (Formal);
5378 if Is_Descendent_Of_Address (Etype (Formal)) then
5379 Address_Kludge := True;
5383 Get_Next_Interp (I, It);
5386 end Remove_Address_Interpretations;
5388 -- Start of processing for Remove_Abstract_Operations
5391 if Is_Overloaded (N) then
5392 Get_First_Interp (N, I, It);
5394 while Present (It.Nam) loop
5395 if Is_Overloadable (It.Nam)
5396 and then Is_Abstract_Subprogram (It.Nam)
5397 and then not Is_Dispatching_Operation (It.Nam)
5399 Abstract_Op := It.Nam;
5401 if Is_Descendent_Of_Address (It.Typ) then
5402 Address_Kludge := True;
5406 -- In Ada 2005, this operation does not participate in Overload
5407 -- resolution. If the operation is defined in a predefined
5408 -- unit, it is one of the operations declared abstract in some
5409 -- variants of System, and it must be removed as well.
5411 elsif Ada_Version >= Ada_05
5412 or else Is_Predefined_File_Name
5413 (Unit_File_Name (Get_Source_Unit (It.Nam)))
5420 Get_Next_Interp (I, It);
5423 if No (Abstract_Op) then
5425 -- If some interpretation yields an integer type, it is still
5426 -- possible that there are address interpretations. Remove them
5427 -- if one operand is a literal, to avoid spurious ambiguities
5428 -- on systems where Address is a visible integer type.
5430 if Is_Overloaded (N)
5431 and then Nkind (N) in N_Op
5432 and then Is_Integer_Type (Etype (N))
5434 if Nkind (N) in N_Binary_Op then
5435 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
5436 Remove_Address_Interpretations (Second_Op);
5438 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
5439 Remove_Address_Interpretations (First_Op);
5444 elsif Nkind (N) in N_Op then
5446 -- Remove interpretations that treat literals as addresses. This
5447 -- is never appropriate, even when Address is defined as a visible
5448 -- Integer type. The reason is that we would really prefer Address
5449 -- to behave as a private type, even in this case, which is there
5450 -- only to accommodate oddities of VMS address sizes. If Address
5451 -- is a visible integer type, we get lots of overload ambiguities.
5453 if Nkind (N) in N_Binary_Op then
5455 U1 : constant Boolean :=
5456 Present (Universal_Interpretation (Right_Opnd (N)));
5457 U2 : constant Boolean :=
5458 Present (Universal_Interpretation (Left_Opnd (N)));
5462 Remove_Address_Interpretations (Second_Op);
5466 Remove_Address_Interpretations (First_Op);
5469 if not (U1 and U2) then
5471 -- Remove corresponding predefined operator, which is
5472 -- always added to the overload set.
5474 Get_First_Interp (N, I, It);
5475 while Present (It.Nam) loop
5476 if Scope (It.Nam) = Standard_Standard
5477 and then Base_Type (It.Typ) =
5478 Base_Type (Etype (Abstract_Op))
5483 Get_Next_Interp (I, It);
5486 elsif Is_Overloaded (N)
5487 and then Present (Univ_Type)
5489 -- If both operands have a universal interpretation,
5490 -- it is still necessary to remove interpretations that
5491 -- yield Address. Any remaining ambiguities will be
5492 -- removed in Disambiguate.
5494 Get_First_Interp (N, I, It);
5495 while Present (It.Nam) loop
5496 if Is_Descendent_Of_Address (It.Typ) then
5499 elsif not Is_Type (It.Nam) then
5500 Set_Entity (N, It.Nam);
5503 Get_Next_Interp (I, It);
5509 elsif Nkind (N) = N_Function_Call
5511 (Nkind (Name (N)) = N_Operator_Symbol
5513 (Nkind (Name (N)) = N_Expanded_Name
5515 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
5519 Arg1 : constant Node_Id := First (Parameter_Associations (N));
5520 U1 : constant Boolean :=
5521 Present (Universal_Interpretation (Arg1));
5522 U2 : constant Boolean :=
5523 Present (Next (Arg1)) and then
5524 Present (Universal_Interpretation (Next (Arg1)));
5528 Remove_Address_Interpretations (First_Op);
5532 Remove_Address_Interpretations (Second_Op);
5535 if not (U1 and U2) then
5536 Get_First_Interp (N, I, It);
5537 while Present (It.Nam) loop
5538 if Scope (It.Nam) = Standard_Standard
5539 and then It.Typ = Base_Type (Etype (Abstract_Op))
5544 Get_Next_Interp (I, It);
5550 -- If the removal has left no valid interpretations, emit an error
5551 -- message now and label node as illegal.
5553 if Present (Abstract_Op) then
5554 Get_First_Interp (N, I, It);
5558 -- Removal of abstract operation left no viable candidate
5560 Set_Etype (N, Any_Type);
5561 Error_Msg_Sloc := Sloc (Abstract_Op);
5563 ("cannot call abstract operation& declared#", N, Abstract_Op);
5565 -- In Ada 2005, an abstract operation may disable predefined
5566 -- operators. Since the context is not yet known, we mark the
5567 -- predefined operators as potentially hidden. Do not include
5568 -- predefined operators when addresses are involved since this
5569 -- case is handled separately.
5571 elsif Ada_Version >= Ada_05
5572 and then not Address_Kludge
5574 while Present (It.Nam) loop
5575 if Is_Numeric_Type (It.Typ)
5576 and then Scope (It.Typ) = Standard_Standard
5578 Set_Abstract_Op (I, Abstract_Op);
5581 Get_Next_Interp (I, It);
5586 end Remove_Abstract_Operations;
5588 -----------------------
5589 -- Try_Indirect_Call --
5590 -----------------------
5592 function Try_Indirect_Call
5595 Typ : Entity_Id) return Boolean
5601 pragma Warnings (Off, Call_OK);
5604 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
5606 Actual := First_Actual (N);
5607 Formal := First_Formal (Designated_Type (Typ));
5608 while Present (Actual) and then Present (Formal) loop
5609 if not Has_Compatible_Type (Actual, Etype (Formal)) then
5614 Next_Formal (Formal);
5617 if No (Actual) and then No (Formal) then
5618 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
5620 -- Nam is a candidate interpretation for the name in the call,
5621 -- if it is not an indirect call.
5623 if not Is_Type (Nam)
5624 and then Is_Entity_Name (Name (N))
5626 Set_Entity (Name (N), Nam);
5633 end Try_Indirect_Call;
5635 ----------------------
5636 -- Try_Indexed_Call --
5637 ----------------------
5639 function Try_Indexed_Call
5643 Skip_First : Boolean) return Boolean
5645 Loc : constant Source_Ptr := Sloc (N);
5646 Actuals : constant List_Id := Parameter_Associations (N);
5651 Actual := First (Actuals);
5653 -- If the call was originally written in prefix form, skip the first
5654 -- actual, which is obviously not defaulted.
5660 Index := First_Index (Typ);
5661 while Present (Actual) and then Present (Index) loop
5663 -- If the parameter list has a named association, the expression
5664 -- is definitely a call and not an indexed component.
5666 if Nkind (Actual) = N_Parameter_Association then
5670 if Is_Entity_Name (Actual)
5671 and then Is_Type (Entity (Actual))
5672 and then No (Next (Actual))
5676 Prefix => Make_Function_Call (Loc,
5677 Name => Relocate_Node (Name (N))),
5679 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
5684 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
5692 if No (Actual) and then No (Index) then
5693 Add_One_Interp (N, Nam, Component_Type (Typ));
5695 -- Nam is a candidate interpretation for the name in the call,
5696 -- if it is not an indirect call.
5698 if not Is_Type (Nam)
5699 and then Is_Entity_Name (Name (N))
5701 Set_Entity (Name (N), Nam);
5708 end Try_Indexed_Call;
5710 --------------------------
5711 -- Try_Object_Operation --
5712 --------------------------
5714 function Try_Object_Operation (N : Node_Id) return Boolean is
5715 K : constant Node_Kind := Nkind (Parent (N));
5716 Is_Subprg_Call : constant Boolean := Nkind_In
5717 (K, N_Procedure_Call_Statement,
5719 Loc : constant Source_Ptr := Sloc (N);
5720 Obj : constant Node_Id := Prefix (N);
5721 Subprog : constant Node_Id :=
5722 Make_Identifier (Sloc (Selector_Name (N)),
5723 Chars => Chars (Selector_Name (N)));
5724 -- Identifier on which possible interpretations will be collected
5726 Report_Error : Boolean := False;
5727 -- If no candidate interpretation matches the context, redo the
5728 -- analysis with error enabled to provide additional information.
5731 Candidate : Entity_Id := Empty;
5732 New_Call_Node : Node_Id := Empty;
5733 Node_To_Replace : Node_Id;
5734 Obj_Type : Entity_Id := Etype (Obj);
5735 Success : Boolean := False;
5737 function Valid_Candidate
5740 Subp : Entity_Id) return Entity_Id;
5741 -- If the subprogram is a valid interpretation, record it, and add
5742 -- to the list of interpretations of Subprog.
5744 procedure Complete_Object_Operation
5745 (Call_Node : Node_Id;
5746 Node_To_Replace : Node_Id);
5747 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
5748 -- Call_Node, insert the object (or its dereference) as the first actual
5749 -- in the call, and complete the analysis of the call.
5751 procedure Report_Ambiguity (Op : Entity_Id);
5752 -- If a prefixed procedure call is ambiguous, indicate whether the
5753 -- call includes an implicit dereference or an implicit 'Access.
5755 procedure Transform_Object_Operation
5756 (Call_Node : out Node_Id;
5757 Node_To_Replace : out Node_Id);
5758 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
5759 -- Call_Node is the resulting subprogram call, Node_To_Replace is
5760 -- either N or the parent of N, and Subprog is a reference to the
5761 -- subprogram we are trying to match.
5763 function Try_Class_Wide_Operation
5764 (Call_Node : Node_Id;
5765 Node_To_Replace : Node_Id) return Boolean;
5766 -- Traverse all ancestor types looking for a class-wide subprogram
5767 -- for which the current operation is a valid non-dispatching call.
5769 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
5770 -- If prefix is overloaded, its interpretation may include different
5771 -- tagged types, and we must examine the primitive operations and
5772 -- the class-wide operations of each in order to find candidate
5773 -- interpretations for the call as a whole.
5775 function Try_Primitive_Operation
5776 (Call_Node : Node_Id;
5777 Node_To_Replace : Node_Id) return Boolean;
5778 -- Traverse the list of primitive subprograms looking for a dispatching
5779 -- operation for which the current node is a valid call .
5781 ---------------------
5782 -- Valid_Candidate --
5783 ---------------------
5785 function Valid_Candidate
5788 Subp : Entity_Id) return Entity_Id
5790 Comp_Type : Entity_Id;
5793 -- If the subprogram is a valid interpretation, record it in global
5794 -- variable Subprog, to collect all possible overloadings.
5797 if Subp /= Entity (Subprog) then
5798 Add_One_Interp (Subprog, Subp, Etype (Subp));
5802 -- If the call may be an indexed call, retrieve component type of
5803 -- resulting expression, and add possible interpretation.
5807 if Nkind (Call) = N_Function_Call
5808 and then Nkind (Parent (N)) = N_Indexed_Component
5809 and then Needs_One_Actual (Subp)
5811 if Is_Array_Type (Etype (Subp)) then
5812 Comp_Type := Component_Type (Etype (Subp));
5814 elsif Is_Access_Type (Etype (Subp))
5815 and then Is_Array_Type (Designated_Type (Etype (Subp)))
5817 Comp_Type := Component_Type (Designated_Type (Etype (Subp)));
5821 if Present (Comp_Type)
5822 and then Etype (Subprog) /= Comp_Type
5824 Add_One_Interp (Subprog, Subp, Comp_Type);
5827 if Etype (Call) /= Any_Type then
5832 end Valid_Candidate;
5834 -------------------------------
5835 -- Complete_Object_Operation --
5836 -------------------------------
5838 procedure Complete_Object_Operation
5839 (Call_Node : Node_Id;
5840 Node_To_Replace : Node_Id)
5842 Control : constant Entity_Id := First_Formal (Entity (Subprog));
5843 Formal_Type : constant Entity_Id := Etype (Control);
5844 First_Actual : Node_Id;
5847 -- Place the name of the operation, with its interpretations,
5848 -- on the rewritten call.
5850 Set_Name (Call_Node, Subprog);
5852 First_Actual := First (Parameter_Associations (Call_Node));
5854 -- For cross-reference purposes, treat the new node as being in
5855 -- the source if the original one is.
5857 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
5858 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
5860 if Nkind (N) = N_Selected_Component
5861 and then not Inside_A_Generic
5863 Set_Entity (Selector_Name (N), Entity (Subprog));
5866 -- If need be, rewrite first actual as an explicit dereference
5867 -- If the call is overloaded, the rewriting can only be done
5868 -- once the primitive operation is identified.
5870 if Is_Overloaded (Subprog) then
5872 -- The prefix itself may be overloaded, and its interpretations
5873 -- must be propagated to the new actual in the call.
5875 if Is_Overloaded (Obj) then
5876 Save_Interps (Obj, First_Actual);
5879 Rewrite (First_Actual, Obj);
5881 elsif not Is_Access_Type (Formal_Type)
5882 and then Is_Access_Type (Etype (Obj))
5884 Rewrite (First_Actual,
5885 Make_Explicit_Dereference (Sloc (Obj), Obj));
5886 Analyze (First_Actual);
5888 -- If we need to introduce an explicit dereference, verify that
5889 -- the resulting actual is compatible with the mode of the formal.
5891 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
5892 and then Is_Access_Constant (Etype (Obj))
5895 ("expect variable in call to&", Prefix (N), Entity (Subprog));
5898 -- Conversely, if the formal is an access parameter and the object
5899 -- is not, replace the actual with a 'Access reference. Its analysis
5900 -- will check that the object is aliased.
5902 elsif Is_Access_Type (Formal_Type)
5903 and then not Is_Access_Type (Etype (Obj))
5905 -- A special case: A.all'access is illegal if A is an access to a
5906 -- constant and the context requires an access to a variable.
5908 if not Is_Access_Constant (Formal_Type) then
5909 if (Nkind (Obj) = N_Explicit_Dereference
5910 and then Is_Access_Constant (Etype (Prefix (Obj))))
5911 or else not Is_Variable (Obj)
5914 ("actual for& must be a variable", Obj, Control);
5918 Rewrite (First_Actual,
5919 Make_Attribute_Reference (Loc,
5920 Attribute_Name => Name_Access,
5921 Prefix => Relocate_Node (Obj)));
5923 if not Is_Aliased_View (Obj) then
5925 ("object in prefixed call to& must be aliased"
5926 & " (RM-2005 4.3.1 (13))",
5927 Prefix (First_Actual), Subprog);
5930 Analyze (First_Actual);
5933 if Is_Overloaded (Obj) then
5934 Save_Interps (Obj, First_Actual);
5937 Rewrite (First_Actual, Obj);
5940 Rewrite (Node_To_Replace, Call_Node);
5942 -- Propagate the interpretations collected in subprog to the new
5943 -- function call node, to be resolved from context.
5945 if Is_Overloaded (Subprog) then
5946 Save_Interps (Subprog, Node_To_Replace);
5948 Analyze (Node_To_Replace);
5950 end Complete_Object_Operation;
5952 ----------------------
5953 -- Report_Ambiguity --
5954 ----------------------
5956 procedure Report_Ambiguity (Op : Entity_Id) is
5957 Access_Formal : constant Boolean :=
5958 Is_Access_Type (Etype (First_Formal (Op)));
5959 Access_Actual : constant Boolean :=
5960 Is_Access_Type (Etype (Prefix (N)));
5963 Error_Msg_Sloc := Sloc (Op);
5965 if Access_Formal and then not Access_Actual then
5966 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
5968 ("\possible interpretation"
5969 & " (inherited, with implicit 'Access) #", N);
5972 ("\possible interpretation (with implicit 'Access) #", N);
5975 elsif not Access_Formal and then Access_Actual then
5976 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
5978 ("\possible interpretation"
5979 & " ( inherited, with implicit dereference) #", N);
5982 ("\possible interpretation (with implicit dereference) #", N);
5986 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
5987 Error_Msg_N ("\possible interpretation (inherited)#", N);
5989 Error_Msg_N ("\possible interpretation#", N);
5992 end Report_Ambiguity;
5994 --------------------------------
5995 -- Transform_Object_Operation --
5996 --------------------------------
5998 procedure Transform_Object_Operation
5999 (Call_Node : out Node_Id;
6000 Node_To_Replace : out Node_Id)
6002 Dummy : constant Node_Id := New_Copy (Obj);
6003 -- Placeholder used as a first parameter in the call, replaced
6004 -- eventually by the proper object.
6006 Parent_Node : constant Node_Id := Parent (N);
6012 -- Common case covering 1) Call to a procedure and 2) Call to a
6013 -- function that has some additional actuals.
6015 if Nkind_In (Parent_Node, N_Function_Call,
6016 N_Procedure_Call_Statement)
6018 -- N is a selected component node containing the name of the
6019 -- subprogram. If N is not the name of the parent node we must
6020 -- not replace the parent node by the new construct. This case
6021 -- occurs when N is a parameterless call to a subprogram that
6022 -- is an actual parameter of a call to another subprogram. For
6024 -- Some_Subprogram (..., Obj.Operation, ...)
6026 and then Name (Parent_Node) = N
6028 Node_To_Replace := Parent_Node;
6030 Actuals := Parameter_Associations (Parent_Node);
6032 if Present (Actuals) then
6033 Prepend (Dummy, Actuals);
6035 Actuals := New_List (Dummy);
6038 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6040 Make_Procedure_Call_Statement (Loc,
6041 Name => New_Copy (Subprog),
6042 Parameter_Associations => Actuals);
6046 Make_Function_Call (Loc,
6047 Name => New_Copy (Subprog),
6048 Parameter_Associations => Actuals);
6052 -- Before analysis, a function call appears as an indexed component
6053 -- if there are no named associations.
6055 elsif Nkind (Parent_Node) = N_Indexed_Component
6056 and then N = Prefix (Parent_Node)
6058 Node_To_Replace := Parent_Node;
6060 Actuals := Expressions (Parent_Node);
6062 Actual := First (Actuals);
6063 while Present (Actual) loop
6068 Prepend (Dummy, Actuals);
6071 Make_Function_Call (Loc,
6072 Name => New_Copy (Subprog),
6073 Parameter_Associations => Actuals);
6075 -- Parameterless call: Obj.F is rewritten as F (Obj)
6078 Node_To_Replace := N;
6081 Make_Function_Call (Loc,
6082 Name => New_Copy (Subprog),
6083 Parameter_Associations => New_List (Dummy));
6085 end Transform_Object_Operation;
6087 ------------------------------
6088 -- Try_Class_Wide_Operation --
6089 ------------------------------
6091 function Try_Class_Wide_Operation
6092 (Call_Node : Node_Id;
6093 Node_To_Replace : Node_Id) return Boolean
6095 Anc_Type : Entity_Id;
6096 Matching_Op : Entity_Id := Empty;
6099 procedure Traverse_Homonyms
6100 (Anc_Type : Entity_Id;
6101 Error : out Boolean);
6102 -- Traverse the homonym chain of the subprogram searching for those
6103 -- homonyms whose first formal has the Anc_Type's class-wide type,
6104 -- or an anonymous access type designating the class-wide type. If
6105 -- an ambiguity is detected, then Error is set to True.
6107 procedure Traverse_Interfaces
6108 (Anc_Type : Entity_Id;
6109 Error : out Boolean);
6110 -- Traverse the list of interfaces, if any, associated with Anc_Type
6111 -- and search for acceptable class-wide homonyms associated with each
6112 -- interface. If an ambiguity is detected, then Error is set to True.
6114 -----------------------
6115 -- Traverse_Homonyms --
6116 -----------------------
6118 procedure Traverse_Homonyms
6119 (Anc_Type : Entity_Id;
6120 Error : out Boolean)
6122 Cls_Type : Entity_Id;
6130 Cls_Type := Class_Wide_Type (Anc_Type);
6132 Hom := Current_Entity (Subprog);
6134 -- Find operation whose first parameter is of the class-wide
6135 -- type, a subtype thereof, or an anonymous access to same.
6137 while Present (Hom) loop
6138 if (Ekind (Hom) = E_Procedure
6140 Ekind (Hom) = E_Function)
6141 and then Scope (Hom) = Scope (Anc_Type)
6142 and then Present (First_Formal (Hom))
6144 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6146 (Is_Access_Type (Etype (First_Formal (Hom)))
6148 Ekind (Etype (First_Formal (Hom))) =
6149 E_Anonymous_Access_Type
6152 (Designated_Type (Etype (First_Formal (Hom)))) =
6155 Set_Etype (Call_Node, Any_Type);
6156 Set_Is_Overloaded (Call_Node, False);
6159 if No (Matching_Op) then
6160 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6161 Set_Etype (Call_Node, Any_Type);
6162 Set_Parent (Call_Node, Parent (Node_To_Replace));
6164 Set_Name (Call_Node, Hom_Ref);
6169 Report => Report_Error,
6171 Skip_First => True);
6174 Valid_Candidate (Success, Call_Node, Hom);
6180 Report => Report_Error,
6182 Skip_First => True);
6184 if Present (Valid_Candidate (Success, Call_Node, Hom))
6185 and then Nkind (Call_Node) /= N_Function_Call
6187 Error_Msg_NE ("ambiguous call to&", N, Hom);
6188 Report_Ambiguity (Matching_Op);
6189 Report_Ambiguity (Hom);
6196 Hom := Homonym (Hom);
6198 end Traverse_Homonyms;
6200 -------------------------
6201 -- Traverse_Interfaces --
6202 -------------------------
6204 procedure Traverse_Interfaces
6205 (Anc_Type : Entity_Id;
6206 Error : out Boolean)
6208 Intface_List : constant List_Id :=
6209 Abstract_Interface_List (Anc_Type);
6215 if Is_Non_Empty_List (Intface_List) then
6216 Intface := First (Intface_List);
6217 while Present (Intface) loop
6219 -- Look for acceptable class-wide homonyms associated with
6222 Traverse_Homonyms (Etype (Intface), Error);
6228 -- Continue the search by looking at each of the interface's
6229 -- associated interface ancestors.
6231 Traverse_Interfaces (Etype (Intface), Error);
6240 end Traverse_Interfaces;
6242 -- Start of processing for Try_Class_Wide_Operation
6245 -- Loop through ancestor types (including interfaces), traversing
6246 -- the homonym chain of the subprogram, trying out those homonyms
6247 -- whose first formal has the class-wide type of the ancestor, or
6248 -- an anonymous access type designating the class-wide type.
6250 Anc_Type := Obj_Type;
6252 -- Look for a match among homonyms associated with the ancestor
6254 Traverse_Homonyms (Anc_Type, Error);
6260 -- Continue the search for matches among homonyms associated with
6261 -- any interfaces implemented by the ancestor.
6263 Traverse_Interfaces (Anc_Type, Error);
6269 exit when Etype (Anc_Type) = Anc_Type;
6270 Anc_Type := Etype (Anc_Type);
6273 if Present (Matching_Op) then
6274 Set_Etype (Call_Node, Etype (Matching_Op));
6277 return Present (Matching_Op);
6278 end Try_Class_Wide_Operation;
6280 -----------------------------------
6281 -- Try_One_Prefix_Interpretation --
6282 -----------------------------------
6284 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6288 if Is_Access_Type (Obj_Type) then
6289 Obj_Type := Designated_Type (Obj_Type);
6292 if Ekind (Obj_Type) = E_Private_Subtype then
6293 Obj_Type := Base_Type (Obj_Type);
6296 if Is_Class_Wide_Type (Obj_Type) then
6297 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6300 -- The type may have be obtained through a limited_with clause,
6301 -- in which case the primitive operations are available on its
6302 -- non-limited view. If still incomplete, retrieve full view.
6304 if Ekind (Obj_Type) = E_Incomplete_Type
6305 and then From_With_Type (Obj_Type)
6307 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6310 -- If the object is not tagged, or the type is still an incomplete
6311 -- type, this is not a prefixed call.
6313 if not Is_Tagged_Type (Obj_Type)
6314 or else Is_Incomplete_Type (Obj_Type)
6319 if Try_Primitive_Operation
6320 (Call_Node => New_Call_Node,
6321 Node_To_Replace => Node_To_Replace)
6323 Try_Class_Wide_Operation
6324 (Call_Node => New_Call_Node,
6325 Node_To_Replace => Node_To_Replace)
6329 end Try_One_Prefix_Interpretation;
6331 -----------------------------
6332 -- Try_Primitive_Operation --
6333 -----------------------------
6335 function Try_Primitive_Operation
6336 (Call_Node : Node_Id;
6337 Node_To_Replace : Node_Id) return Boolean
6340 Prim_Op : Entity_Id;
6341 Matching_Op : Entity_Id := Empty;
6342 Prim_Op_Ref : Node_Id := Empty;
6344 Corr_Type : Entity_Id := Empty;
6345 -- If the prefix is a synchronized type, the controlling type of
6346 -- the primitive operation is the corresponding record type, else
6347 -- this is the object type itself.
6349 Success : Boolean := False;
6351 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
6352 -- For tagged types the candidate interpretations are found in
6353 -- the list of primitive operations of the type and its ancestors.
6354 -- For formal tagged types we have to find the operations declared
6355 -- in the same scope as the type (including in the generic formal
6356 -- part) because the type itself carries no primitive operations,
6357 -- except for formal derived types that inherit the operations of
6358 -- the parent and progenitors.
6359 -- If the context is a generic subprogram body, the generic formals
6360 -- are visible by name, but are not in the entity list of the
6361 -- subprogram because that list starts with the subprogram formals.
6362 -- We retrieve the candidate operations from the generic declaration.
6364 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
6365 -- Verify that the prefix, dereferenced if need be, is a valid
6366 -- controlling argument in a call to Op. The remaining actuals
6367 -- are checked in the subsequent call to Analyze_One_Call.
6369 ------------------------------
6370 -- Collect_Generic_Type_Ops --
6371 ------------------------------
6373 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
6374 Bas : constant Entity_Id := Base_Type (T);
6375 Candidates : constant Elist_Id := New_Elmt_List;
6379 procedure Check_Candidate;
6380 -- The operation is a candidate if its first parameter is a
6381 -- controlling operand of the desired type.
6383 -----------------------
6384 -- Check_Candidate; --
6385 -----------------------
6387 procedure Check_Candidate is
6389 Formal := First_Formal (Subp);
6392 and then Is_Controlling_Formal (Formal)
6394 (Base_Type (Etype (Formal)) = Bas
6396 (Is_Access_Type (Etype (Formal))
6397 and then Designated_Type (Etype (Formal)) = Bas))
6399 Append_Elmt (Subp, Candidates);
6401 end Check_Candidate;
6403 -- Start of processing for Collect_Generic_Type_Ops
6406 if Is_Derived_Type (T) then
6407 return Primitive_Operations (T);
6409 elsif Ekind (Scope (T)) = E_Procedure
6410 or else Ekind (Scope (T)) = E_Function
6412 -- Scan the list of generic formals to find subprograms
6413 -- that may have a first controlling formal of the type.
6420 First (Generic_Formal_Declarations
6421 (Unit_Declaration_Node (Scope (T))));
6422 while Present (Decl) loop
6423 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
6424 Subp := Defining_Entity (Decl);
6435 -- Scan the list of entities declared in the same scope as
6436 -- the type. In general this will be an open scope, given that
6437 -- the call we are analyzing can only appear within a generic
6438 -- declaration or body (either the one that declares T, or a
6441 Subp := First_Entity (Scope (T));
6442 while Present (Subp) loop
6443 if Is_Overloadable (Subp) then
6452 end Collect_Generic_Type_Ops;
6454 -----------------------------
6455 -- Valid_First_Argument_Of --
6456 -----------------------------
6458 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
6459 Typ : Entity_Id := Etype (First_Formal (Op));
6462 if Is_Concurrent_Type (Typ)
6463 and then Present (Corresponding_Record_Type (Typ))
6465 Typ := Corresponding_Record_Type (Typ);
6468 -- Simple case. Object may be a subtype of the tagged type or
6469 -- may be the corresponding record of a synchronized type.
6471 return Obj_Type = Typ
6472 or else Base_Type (Obj_Type) = Typ
6473 or else Corr_Type = Typ
6475 -- Prefix can be dereferenced
6478 (Is_Access_Type (Corr_Type)
6479 and then Designated_Type (Corr_Type) = Typ)
6481 -- Formal is an access parameter, for which the object
6482 -- can provide an access.
6485 (Ekind (Typ) = E_Anonymous_Access_Type
6486 and then Designated_Type (Typ) = Base_Type (Corr_Type));
6487 end Valid_First_Argument_Of;
6489 -- Start of processing for Try_Primitive_Operation
6492 -- Look for subprograms in the list of primitive operations. The name
6493 -- must be identical, and the kind of call indicates the expected
6494 -- kind of operation (function or procedure). If the type is a
6495 -- (tagged) synchronized type, the primitive ops are attached to the
6496 -- corresponding record (base) type.
6498 if Is_Concurrent_Type (Obj_Type) then
6499 if not Present (Corresponding_Record_Type (Obj_Type)) then
6503 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
6504 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
6506 elsif not Is_Generic_Type (Obj_Type) then
6507 Corr_Type := Obj_Type;
6508 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
6511 Corr_Type := Obj_Type;
6512 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
6515 while Present (Elmt) loop
6516 Prim_Op := Node (Elmt);
6518 if Chars (Prim_Op) = Chars (Subprog)
6519 and then Present (First_Formal (Prim_Op))
6520 and then Valid_First_Argument_Of (Prim_Op)
6522 (Nkind (Call_Node) = N_Function_Call)
6523 = (Ekind (Prim_Op) = E_Function)
6525 -- Ada 2005 (AI-251): If this primitive operation corresponds
6526 -- with an immediate ancestor interface there is no need to add
6527 -- it to the list of interpretations; the corresponding aliased
6528 -- primitive is also in this list of primitive operations and
6529 -- will be used instead.
6531 if (Present (Interface_Alias (Prim_Op))
6532 and then Is_Ancestor (Find_Dispatching_Type
6533 (Alias (Prim_Op)), Corr_Type))
6536 -- Do not consider hidden primitives unless the type is
6537 -- in an open scope or we are within an instance, where
6538 -- visibility is known to be correct.
6540 (Is_Hidden (Prim_Op)
6541 and then not Is_Immediately_Visible (Obj_Type)
6542 and then not In_Instance)
6547 Set_Etype (Call_Node, Any_Type);
6548 Set_Is_Overloaded (Call_Node, False);
6550 if No (Matching_Op) then
6551 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
6552 Candidate := Prim_Op;
6554 Set_Parent (Call_Node, Parent (Node_To_Replace));
6556 Set_Name (Call_Node, Prim_Op_Ref);
6562 Report => Report_Error,
6564 Skip_First => True);
6566 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
6568 -- More than one interpretation, collect for subsequent
6569 -- disambiguation. If this is a procedure call and there
6570 -- is another match, report ambiguity now.
6576 Report => Report_Error,
6578 Skip_First => True);
6580 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
6581 and then Nkind (Call_Node) /= N_Function_Call
6583 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
6584 Report_Ambiguity (Matching_Op);
6585 Report_Ambiguity (Prim_Op);
6595 if Present (Matching_Op) then
6596 Set_Etype (Call_Node, Etype (Matching_Op));
6599 return Present (Matching_Op);
6600 end Try_Primitive_Operation;
6602 -- Start of processing for Try_Object_Operation
6605 Analyze_Expression (Obj);
6607 -- Analyze the actuals if node is known to be a subprogram call
6609 if Is_Subprg_Call and then N = Name (Parent (N)) then
6610 Actual := First (Parameter_Associations (Parent (N)));
6611 while Present (Actual) loop
6612 Analyze_Expression (Actual);
6617 -- Build a subprogram call node, using a copy of Obj as its first
6618 -- actual. This is a placeholder, to be replaced by an explicit
6619 -- dereference when needed.
6621 Transform_Object_Operation
6622 (Call_Node => New_Call_Node,
6623 Node_To_Replace => Node_To_Replace);
6625 Set_Etype (New_Call_Node, Any_Type);
6626 Set_Etype (Subprog, Any_Type);
6627 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
6629 if not Is_Overloaded (Obj) then
6630 Try_One_Prefix_Interpretation (Obj_Type);
6637 Get_First_Interp (Obj, I, It);
6638 while Present (It.Nam) loop
6639 Try_One_Prefix_Interpretation (It.Typ);
6640 Get_Next_Interp (I, It);
6645 if Etype (New_Call_Node) /= Any_Type then
6646 Complete_Object_Operation
6647 (Call_Node => New_Call_Node,
6648 Node_To_Replace => Node_To_Replace);
6651 elsif Present (Candidate) then
6653 -- The argument list is not type correct. Re-analyze with error
6654 -- reporting enabled, and use one of the possible candidates.
6655 -- In All_Errors_Mode, re-analyze all failed interpretations.
6657 if All_Errors_Mode then
6658 Report_Error := True;
6659 if Try_Primitive_Operation
6660 (Call_Node => New_Call_Node,
6661 Node_To_Replace => Node_To_Replace)
6664 Try_Class_Wide_Operation
6665 (Call_Node => New_Call_Node,
6666 Node_To_Replace => Node_To_Replace)
6673 (N => New_Call_Node,
6677 Skip_First => True);
6680 -- No need for further errors
6685 -- There was no candidate operation, so report it as an error
6686 -- in the caller: Analyze_Selected_Component.
6690 end Try_Object_Operation;
6696 procedure wpo (T : Entity_Id) is
6701 if not Is_Tagged_Type (T) then
6705 E := First_Elmt (Primitive_Operations (Base_Type (T)));
6706 while Present (E) loop
6708 Write_Int (Int (Op));
6709 Write_Str (" === ");
6710 Write_Name (Chars (Op));
6712 Write_Name (Chars (Scope (Op)));