1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2003, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Errout; use Errout;
31 with Exp_Util; use Exp_Util;
32 with Hostparm; use Hostparm;
33 with Itypes; use Itypes;
34 with Lib.Xref; use Lib.Xref;
35 with Namet; use Namet;
36 with Nlists; use Nlists;
37 with Nmake; use Nmake;
39 with Output; use Output;
40 with Restrict; use Restrict;
42 with Sem_Cat; use Sem_Cat;
43 with Sem_Ch3; use Sem_Ch3;
44 with Sem_Ch8; use Sem_Ch8;
45 with Sem_Dist; use Sem_Dist;
46 with Sem_Eval; use Sem_Eval;
47 with Sem_Res; use Sem_Res;
48 with Sem_Util; use Sem_Util;
49 with Sem_Type; use Sem_Type;
50 with Stand; use Stand;
51 with Sinfo; use Sinfo;
52 with Snames; use Snames;
53 with Tbuild; use Tbuild;
55 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
57 package body Sem_Ch4 is
59 -----------------------
60 -- Local Subprograms --
61 -----------------------
63 procedure Analyze_Expression (N : Node_Id);
64 -- For expressions that are not names, this is just a call to analyze.
65 -- If the expression is a name, it may be a call to a parameterless
66 -- function, and if so must be converted into an explicit call node
67 -- and analyzed as such. This deproceduring must be done during the first
68 -- pass of overload resolution, because otherwise a procedure call with
69 -- overloaded actuals may fail to resolve. See 4327-001 for an example.
71 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id);
72 -- Analyze a call of the form "+"(x, y), etc. The prefix of the call
73 -- is an operator name or an expanded name whose selector is an operator
74 -- name, and one possible interpretation is as a predefined operator.
76 procedure Analyze_Overloaded_Selected_Component (N : Node_Id);
77 -- If the prefix of a selected_component is overloaded, the proper
78 -- interpretation that yields a record type with the proper selector
79 -- name must be selected.
81 procedure Analyze_User_Defined_Binary_Op (N : Node_Id; Op_Id : Entity_Id);
82 -- Procedure to analyze a user defined binary operator, which is resolved
83 -- like a function, but instead of a list of actuals it is presented
84 -- with the left and right operands of an operator node.
86 procedure Analyze_User_Defined_Unary_Op (N : Node_Id; Op_Id : Entity_Id);
87 -- Procedure to analyze a user defined unary operator, which is resolved
88 -- like a function, but instead of a list of actuals, it is presented with
89 -- the operand of the operator node.
91 procedure Ambiguous_Operands (N : Node_Id);
92 -- for equality, membership, and comparison operators with overloaded
93 -- arguments, list possible interpretations.
95 procedure Analyze_One_Call
99 Success : out Boolean);
100 -- Check one interpretation of an overloaded subprogram name for
101 -- compatibility with the types of the actuals in a call. If there is a
102 -- single interpretation which does not match, post error if Report is
105 -- Nam is the entity that provides the formals against which the actuals
106 -- are checked. Nam is either the name of a subprogram, or the internal
107 -- subprogram type constructed for an access_to_subprogram. If the actuals
108 -- are compatible with Nam, then Nam is added to the list of candidate
109 -- interpretations for N, and Success is set to True.
111 procedure Check_Misspelled_Selector
114 -- Give possible misspelling diagnostic if Sel is likely to be
115 -- a misspelling of one of the selectors of the Prefix.
116 -- This is called by Analyze_Selected_Component after producing
117 -- an invalid selector error message.
119 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean;
120 -- Verify that type T is declared in scope S. Used to find intepretations
121 -- for operators given by expanded names. This is abstracted as a separate
122 -- function to handle extensions to System, where S is System, but T is
123 -- declared in the extension.
125 procedure Find_Arithmetic_Types
129 -- L and R are the operands of an arithmetic operator. Find
130 -- consistent pairs of interpretations for L and R that have a
131 -- numeric type consistent with the semantics of the operator.
133 procedure Find_Comparison_Types
137 -- L and R are operands of a comparison operator. Find consistent
138 -- pairs of interpretations for L and R.
140 procedure Find_Concatenation_Types
144 -- For the four varieties of concatenation.
146 procedure Find_Equality_Types
150 -- Ditto for equality operators.
152 procedure Find_Boolean_Types
156 -- Ditto for binary logical operations.
158 procedure Find_Negation_Types
162 -- Find consistent interpretation for operand of negation operator.
164 procedure Find_Non_Universal_Interpretations
169 -- For equality and comparison operators, the result is always boolean,
170 -- and the legality of the operation is determined from the visibility
171 -- of the operand types. If one of the operands has a universal interpre-
172 -- tation, the legality check uses some compatible non-universal
173 -- interpretation of the other operand. N can be an operator node, or
174 -- a function call whose name is an operator designator.
176 procedure Find_Unary_Types
180 -- Unary arithmetic types: plus, minus, abs.
182 procedure Check_Arithmetic_Pair
186 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid
187 -- types for left and right operand. Determine whether they constitute
188 -- a valid pair for the given operator, and record the corresponding
189 -- interpretation of the operator node. The node N may be an operator
190 -- node (the usual case) or a function call whose prefix is an operator
191 -- designator. In both cases Op_Id is the operator name itself.
193 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id);
194 -- Give detailed information on overloaded call where none of the
195 -- interpretations match. N is the call node, Nam the designator for
196 -- the overloaded entity being called.
198 function Junk_Operand (N : Node_Id) return Boolean;
199 -- Test for an operand that is an inappropriate entity (e.g. a package
200 -- name or a label). If so, issue an error message and return True. If
201 -- the operand is not an inappropriate entity kind, return False.
203 procedure Operator_Check (N : Node_Id);
204 -- Verify that an operator has received some valid interpretation.
205 -- If none was found, determine whether a use clause would make the
206 -- operation legal. The variable Candidate_Type (defined in Sem_Type) is
207 -- set for every type compatible with the operator, even if the operator
208 -- for the type is not directly visible. The routine uses this type to emit
209 -- a more informative message.
211 function Try_Indexed_Call
216 -- If a function has defaults for all its actuals, a call to it may
217 -- in fact be an indexing on the result of the call. Try_Indexed_Call
218 -- attempts the interpretation as an indexing, prior to analysis as
219 -- a call. If both are possible, the node is overloaded with both
220 -- interpretations (same symbol but two different types).
222 function Try_Indirect_Call
227 -- Similarly, a function F that needs no actuals can return an access
228 -- to a subprogram, and the call F (X) interpreted as F.all (X). In
229 -- this case the call may be overloaded with both interpretations.
231 ------------------------
232 -- Ambiguous_Operands --
233 ------------------------
235 procedure Ambiguous_Operands (N : Node_Id) is
236 procedure List_Operand_Interps (Opnd : Node_Id);
238 procedure List_Operand_Interps (Opnd : Node_Id) is
243 if Is_Overloaded (Opnd) then
244 if Nkind (Opnd) in N_Op then
247 elsif Nkind (Opnd) = N_Function_Call then
258 if Opnd = Left_Opnd (N) then
260 ("\left operand has the following interpretations", N);
263 ("\right operand has the following interpretations", N);
267 List_Interps (Nam, Err);
268 end List_Operand_Interps;
272 or else Nkind (N) = N_Not_In
274 Error_Msg_N ("ambiguous operands for membership", N);
276 elsif Nkind (N) = N_Op_Eq
277 or else Nkind (N) = N_Op_Ne
279 Error_Msg_N ("ambiguous operands for equality", N);
282 Error_Msg_N ("ambiguous operands for comparison", N);
285 if All_Errors_Mode then
286 List_Operand_Interps (Left_Opnd (N));
287 List_Operand_Interps (Right_Opnd (N));
292 "\use '/'R'E'P'O'R'T'_'E'R'R'O'R'S'='F'U'L'L for details",
295 Error_Msg_N ("\use -gnatf for details", N);
298 end Ambiguous_Operands;
300 -----------------------
301 -- Analyze_Aggregate --
302 -----------------------
304 -- Most of the analysis of Aggregates requires that the type be known,
305 -- and is therefore put off until resolution.
307 procedure Analyze_Aggregate (N : Node_Id) is
309 if No (Etype (N)) then
310 Set_Etype (N, Any_Composite);
312 end Analyze_Aggregate;
314 -----------------------
315 -- Analyze_Allocator --
316 -----------------------
318 procedure Analyze_Allocator (N : Node_Id) is
319 Loc : constant Source_Ptr := Sloc (N);
320 Sav_Errs : constant Nat := Serious_Errors_Detected;
321 E : Node_Id := Expression (N);
322 Acc_Type : Entity_Id;
326 Check_Restriction (No_Allocators, N);
328 if Nkind (E) = N_Qualified_Expression then
329 Acc_Type := Create_Itype (E_Allocator_Type, N);
330 Set_Etype (Acc_Type, Acc_Type);
331 Init_Size_Align (Acc_Type);
332 Find_Type (Subtype_Mark (E));
333 Type_Id := Entity (Subtype_Mark (E));
334 Check_Fully_Declared (Type_Id, N);
335 Set_Directly_Designated_Type (Acc_Type, Type_Id);
337 if Is_Protected_Type (Type_Id) then
338 Check_Restriction (No_Protected_Type_Allocators, N);
341 if Is_Limited_Type (Type_Id)
342 and then Comes_From_Source (N)
343 and then not In_Instance_Body
345 Error_Msg_N ("initialization not allowed for limited types", N);
346 Explain_Limited_Type (Type_Id, N);
349 Analyze_And_Resolve (Expression (E), Type_Id);
351 -- A qualified expression requires an exact match of the type,
352 -- class-wide matching is not allowed.
354 if Is_Class_Wide_Type (Type_Id)
355 and then Base_Type (Etype (Expression (E))) /= Base_Type (Type_Id)
357 Wrong_Type (Expression (E), Type_Id);
360 Check_Non_Static_Context (Expression (E));
362 -- We don't analyze the qualified expression itself because it's
363 -- part of the allocator
365 Set_Etype (E, Type_Id);
372 -- If the allocator includes a N_Subtype_Indication then a
373 -- constraint is present, otherwise the node is a subtype mark.
374 -- Introduce an explicit subtype declaration into the tree
375 -- defining some anonymous subtype and rewrite the allocator to
376 -- use this subtype rather than the subtype indication.
378 -- It is important to introduce the explicit subtype declaration
379 -- so that the bounds of the subtype indication are attached to
380 -- the tree in case the allocator is inside a generic unit.
382 if Nkind (E) = N_Subtype_Indication then
384 -- A constraint is only allowed for a composite type in Ada
385 -- 95. In Ada 83, a constraint is also allowed for an
386 -- access-to-composite type, but the constraint is ignored.
388 Find_Type (Subtype_Mark (E));
390 if Is_Elementary_Type (Entity (Subtype_Mark (E))) then
392 and then Is_Access_Type (Entity (Subtype_Mark (E))))
394 Error_Msg_N ("constraint not allowed here", E);
396 if Nkind (Constraint (E))
397 = N_Index_Or_Discriminant_Constraint
400 ("\if qualified expression was meant, " &
401 "use apostrophe", Constraint (E));
405 -- Get rid of the bogus constraint:
407 Rewrite (E, New_Copy_Tree (Subtype_Mark (E)));
408 Analyze_Allocator (N);
412 if Expander_Active then
414 Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
417 Make_Subtype_Declaration (Loc,
418 Defining_Identifier => Def_Id,
419 Subtype_Indication => Relocate_Node (E)));
421 if Sav_Errs /= Serious_Errors_Detected
422 and then Nkind (Constraint (E))
423 = N_Index_Or_Discriminant_Constraint
426 ("if qualified expression was meant, " &
427 "use apostrophe!", Constraint (E));
430 E := New_Occurrence_Of (Def_Id, Loc);
431 Rewrite (Expression (N), E);
435 Type_Id := Process_Subtype (E, N);
436 Acc_Type := Create_Itype (E_Allocator_Type, N);
437 Set_Etype (Acc_Type, Acc_Type);
438 Init_Size_Align (Acc_Type);
439 Set_Directly_Designated_Type (Acc_Type, Type_Id);
440 Check_Fully_Declared (Type_Id, N);
442 -- Check for missing initialization. Skip this check if we already
443 -- had errors on analyzing the allocator, since in that case these
444 -- are probably cascaded errors
446 if Is_Indefinite_Subtype (Type_Id)
447 and then Serious_Errors_Detected = Sav_Errs
449 if Is_Class_Wide_Type (Type_Id) then
451 ("initialization required in class-wide allocation", N);
454 ("initialization required in unconstrained allocation", N);
460 if Is_Abstract (Type_Id) then
461 Error_Msg_N ("cannot allocate abstract object", E);
464 if Has_Task (Designated_Type (Acc_Type)) then
465 Check_Restriction (Max_Tasks, N);
466 Check_Restriction (No_Task_Allocators, N);
469 Set_Etype (N, Acc_Type);
471 if not Is_Library_Level_Entity (Acc_Type) then
472 Check_Restriction (No_Local_Allocators, N);
475 if Serious_Errors_Detected > Sav_Errs then
476 Set_Error_Posted (N);
477 Set_Etype (N, Any_Type);
479 end Analyze_Allocator;
481 ---------------------------
482 -- Analyze_Arithmetic_Op --
483 ---------------------------
485 procedure Analyze_Arithmetic_Op (N : Node_Id) is
486 L : constant Node_Id := Left_Opnd (N);
487 R : constant Node_Id := Right_Opnd (N);
491 Candidate_Type := Empty;
492 Analyze_Expression (L);
493 Analyze_Expression (R);
495 -- If the entity is already set, the node is the instantiation of
496 -- a generic node with a non-local reference, or was manufactured
497 -- by a call to Make_Op_xxx. In either case the entity is known to
498 -- be valid, and we do not need to collect interpretations, instead
499 -- we just get the single possible interpretation.
503 if Present (Op_Id) then
504 if Ekind (Op_Id) = E_Operator then
506 if (Nkind (N) = N_Op_Divide or else
507 Nkind (N) = N_Op_Mod or else
508 Nkind (N) = N_Op_Multiply or else
509 Nkind (N) = N_Op_Rem)
510 and then Treat_Fixed_As_Integer (N)
514 Set_Etype (N, Any_Type);
515 Find_Arithmetic_Types (L, R, Op_Id, N);
519 Set_Etype (N, Any_Type);
520 Add_One_Interp (N, Op_Id, Etype (Op_Id));
523 -- Entity is not already set, so we do need to collect interpretations
526 Op_Id := Get_Name_Entity_Id (Chars (N));
527 Set_Etype (N, Any_Type);
529 while Present (Op_Id) loop
530 if Ekind (Op_Id) = E_Operator
531 and then Present (Next_Entity (First_Entity (Op_Id)))
533 Find_Arithmetic_Types (L, R, Op_Id, N);
535 -- The following may seem superfluous, because an operator cannot
536 -- be generic, but this ignores the cleverness of the author of
539 elsif Is_Overloadable (Op_Id) then
540 Analyze_User_Defined_Binary_Op (N, Op_Id);
543 Op_Id := Homonym (Op_Id);
548 end Analyze_Arithmetic_Op;
554 -- Function, procedure, and entry calls are checked here. The Name
555 -- in the call may be overloaded. The actuals have been analyzed
556 -- and may themselves be overloaded. On exit from this procedure, the node
557 -- N may have zero, one or more interpretations. In the first case an error
558 -- message is produced. In the last case, the node is flagged as overloaded
559 -- and the interpretations are collected in All_Interp.
561 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
562 -- the type-checking is similar to that of other calls.
564 procedure Analyze_Call (N : Node_Id) is
565 Actuals : constant List_Id := Parameter_Associations (N);
566 Nam : Node_Id := Name (N);
570 Success : Boolean := False;
572 function Name_Denotes_Function return Boolean;
573 -- If the type of the name is an access to subprogram, this may be
574 -- the type of a name, or the return type of the function being called.
575 -- If the name is not an entity then it can denote a protected function.
576 -- Until we distinguish Etype from Return_Type, we must use this
577 -- routine to resolve the meaning of the name in the call.
579 ---------------------------
580 -- Name_Denotes_Function --
581 ---------------------------
583 function Name_Denotes_Function return Boolean is
585 if Is_Entity_Name (Nam) then
586 return Ekind (Entity (Nam)) = E_Function;
588 elsif Nkind (Nam) = N_Selected_Component then
589 return Ekind (Entity (Selector_Name (Nam))) = E_Function;
594 end Name_Denotes_Function;
596 -- Start of processing for Analyze_Call
599 -- Initialize the type of the result of the call to the error type,
600 -- which will be reset if the type is successfully resolved.
602 Set_Etype (N, Any_Type);
604 if not Is_Overloaded (Nam) then
606 -- Only one interpretation to check
608 if Ekind (Etype (Nam)) = E_Subprogram_Type then
609 Nam_Ent := Etype (Nam);
611 elsif Is_Access_Type (Etype (Nam))
612 and then Ekind (Designated_Type (Etype (Nam))) = E_Subprogram_Type
613 and then not Name_Denotes_Function
615 Nam_Ent := Designated_Type (Etype (Nam));
616 Insert_Explicit_Dereference (Nam);
618 -- Selected component case. Simple entry or protected operation,
619 -- where the entry name is given by the selector name.
621 elsif Nkind (Nam) = N_Selected_Component then
622 Nam_Ent := Entity (Selector_Name (Nam));
624 if Ekind (Nam_Ent) /= E_Entry
625 and then Ekind (Nam_Ent) /= E_Entry_Family
626 and then Ekind (Nam_Ent) /= E_Function
627 and then Ekind (Nam_Ent) /= E_Procedure
629 Error_Msg_N ("name in call is not a callable entity", Nam);
630 Set_Etype (N, Any_Type);
634 -- If the name is an Indexed component, it can be a call to a member
635 -- of an entry family. The prefix must be a selected component whose
636 -- selector is the entry. Analyze_Procedure_Call normalizes several
637 -- kinds of call into this form.
639 elsif Nkind (Nam) = N_Indexed_Component then
641 if Nkind (Prefix (Nam)) = N_Selected_Component then
642 Nam_Ent := Entity (Selector_Name (Prefix (Nam)));
645 Error_Msg_N ("name in call is not a callable entity", Nam);
646 Set_Etype (N, Any_Type);
651 elsif not Is_Entity_Name (Nam) then
652 Error_Msg_N ("name in call is not a callable entity", Nam);
653 Set_Etype (N, Any_Type);
657 Nam_Ent := Entity (Nam);
659 -- If no interpretations, give error message
661 if not Is_Overloadable (Nam_Ent) then
663 L : constant Boolean := Is_List_Member (N);
664 K : constant Node_Kind := Nkind (Parent (N));
667 -- If the node is in a list whose parent is not an
668 -- expression then it must be an attempted procedure call.
670 if L and then K not in N_Subexpr then
671 if Ekind (Entity (Nam)) = E_Generic_Procedure then
673 ("must instantiate generic procedure& before call",
677 ("procedure or entry name expected", Nam);
680 -- Check for tasking cases where only an entry call will do
683 and then (K = N_Entry_Call_Alternative
684 or else K = N_Triggering_Alternative)
686 Error_Msg_N ("entry name expected", Nam);
688 -- Otherwise give general error message
691 Error_Msg_N ("invalid prefix in call", Nam);
699 Analyze_One_Call (N, Nam_Ent, True, Success);
702 -- An overloaded selected component must denote overloaded
703 -- operations of a concurrent type. The interpretations are
704 -- attached to the simple name of those operations.
706 if Nkind (Nam) = N_Selected_Component then
707 Nam := Selector_Name (Nam);
710 Get_First_Interp (Nam, X, It);
712 while Present (It.Nam) loop
715 -- Name may be call that returns an access to subprogram, or more
716 -- generally an overloaded expression one of whose interpretations
717 -- yields an access to subprogram. If the name is an entity, we
718 -- do not dereference, because the node is a call that returns
719 -- the access type: note difference between f(x), where the call
720 -- may return an access subprogram type, and f(x)(y), where the
721 -- type returned by the call to f is implicitly dereferenced to
722 -- analyze the outer call.
724 if Is_Access_Type (Nam_Ent) then
725 Nam_Ent := Designated_Type (Nam_Ent);
727 elsif Is_Access_Type (Etype (Nam_Ent))
728 and then not Is_Entity_Name (Nam)
729 and then Ekind (Designated_Type (Etype (Nam_Ent)))
732 Nam_Ent := Designated_Type (Etype (Nam_Ent));
735 Analyze_One_Call (N, Nam_Ent, False, Success);
737 -- If the interpretation succeeds, mark the proper type of the
738 -- prefix (any valid candidate will do). If not, remove the
739 -- candidate interpretation. This only needs to be done for
740 -- overloaded protected operations, for other entities disambi-
741 -- guation is done directly in Resolve.
744 Set_Etype (Nam, It.Typ);
746 elsif Nkind (Name (N)) = N_Selected_Component
747 or else Nkind (Name (N)) = N_Function_Call
752 Get_Next_Interp (X, It);
755 -- If the name is the result of a function call, it can only
756 -- be a call to a function returning an access to subprogram.
757 -- Insert explicit dereference.
759 if Nkind (Nam) = N_Function_Call then
760 Insert_Explicit_Dereference (Nam);
763 if Etype (N) = Any_Type then
765 -- None of the interpretations is compatible with the actuals
767 Diagnose_Call (N, Nam);
769 -- Special checks for uninstantiated put routines
771 if Nkind (N) = N_Procedure_Call_Statement
772 and then Is_Entity_Name (Nam)
773 and then Chars (Nam) = Name_Put
774 and then List_Length (Actuals) = 1
777 Arg : constant Node_Id := First (Actuals);
781 if Nkind (Arg) = N_Parameter_Association then
782 Typ := Etype (Explicit_Actual_Parameter (Arg));
787 if Is_Signed_Integer_Type (Typ) then
789 ("possible missing instantiation of " &
790 "'Text_'I'O.'Integer_'I'O!", Nam);
792 elsif Is_Modular_Integer_Type (Typ) then
794 ("possible missing instantiation of " &
795 "'Text_'I'O.'Modular_'I'O!", Nam);
797 elsif Is_Floating_Point_Type (Typ) then
799 ("possible missing instantiation of " &
800 "'Text_'I'O.'Float_'I'O!", Nam);
802 elsif Is_Ordinary_Fixed_Point_Type (Typ) then
804 ("possible missing instantiation of " &
805 "'Text_'I'O.'Fixed_'I'O!", Nam);
807 elsif Is_Decimal_Fixed_Point_Type (Typ) then
809 ("possible missing instantiation of " &
810 "'Text_'I'O.'Decimal_'I'O!", Nam);
812 elsif Is_Enumeration_Type (Typ) then
814 ("possible missing instantiation of " &
815 "'Text_'I'O.'Enumeration_'I'O!", Nam);
820 elsif not Is_Overloaded (N)
821 and then Is_Entity_Name (Nam)
823 -- Resolution yields a single interpretation. Verify that
824 -- is has the proper capitalization.
826 Set_Entity_With_Style_Check (Nam, Entity (Nam));
827 Generate_Reference (Entity (Nam), Nam);
829 Set_Etype (Nam, Etype (Entity (Nam)));
836 ---------------------------
837 -- Analyze_Comparison_Op --
838 ---------------------------
840 procedure Analyze_Comparison_Op (N : Node_Id) is
841 L : constant Node_Id := Left_Opnd (N);
842 R : constant Node_Id := Right_Opnd (N);
843 Op_Id : Entity_Id := Entity (N);
846 Set_Etype (N, Any_Type);
847 Candidate_Type := Empty;
849 Analyze_Expression (L);
850 Analyze_Expression (R);
852 if Present (Op_Id) then
854 if Ekind (Op_Id) = E_Operator then
855 Find_Comparison_Types (L, R, Op_Id, N);
857 Add_One_Interp (N, Op_Id, Etype (Op_Id));
860 if Is_Overloaded (L) then
861 Set_Etype (L, Intersect_Types (L, R));
865 Op_Id := Get_Name_Entity_Id (Chars (N));
867 while Present (Op_Id) loop
869 if Ekind (Op_Id) = E_Operator then
870 Find_Comparison_Types (L, R, Op_Id, N);
872 Analyze_User_Defined_Binary_Op (N, Op_Id);
875 Op_Id := Homonym (Op_Id);
880 end Analyze_Comparison_Op;
882 ---------------------------
883 -- Analyze_Concatenation --
884 ---------------------------
886 -- If the only one-dimensional array type in scope is String,
887 -- this is the resulting type of the operation. Otherwise there
888 -- will be a concatenation operation defined for each user-defined
889 -- one-dimensional array.
891 procedure Analyze_Concatenation (N : Node_Id) is
892 L : constant Node_Id := Left_Opnd (N);
893 R : constant Node_Id := Right_Opnd (N);
894 Op_Id : Entity_Id := Entity (N);
899 Set_Etype (N, Any_Type);
900 Candidate_Type := Empty;
902 Analyze_Expression (L);
903 Analyze_Expression (R);
905 -- If the entity is present, the node appears in an instance,
906 -- and denotes a predefined concatenation operation. The resulting
907 -- type is obtained from the arguments when possible. If the arguments
908 -- are aggregates, the array type and the concatenation type must be
911 if Present (Op_Id) then
912 if Ekind (Op_Id) = E_Operator then
914 LT := Base_Type (Etype (L));
915 RT := Base_Type (Etype (R));
917 if Is_Array_Type (LT)
918 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
920 Add_One_Interp (N, Op_Id, LT);
922 elsif Is_Array_Type (RT)
923 and then LT = Base_Type (Component_Type (RT))
925 Add_One_Interp (N, Op_Id, RT);
927 -- If one operand is a string type or a user-defined array type,
928 -- and the other is a literal, result is of the specific type.
931 (Root_Type (LT) = Standard_String
932 or else Scope (LT) /= Standard_Standard)
933 and then Etype (R) = Any_String
935 Add_One_Interp (N, Op_Id, LT);
938 (Root_Type (RT) = Standard_String
939 or else Scope (RT) /= Standard_Standard)
940 and then Etype (L) = Any_String
942 Add_One_Interp (N, Op_Id, RT);
944 elsif not Is_Generic_Type (Etype (Op_Id)) then
945 Add_One_Interp (N, Op_Id, Etype (Op_Id));
948 -- Type and its operations must be visible.
950 Set_Entity (N, Empty);
951 Analyze_Concatenation (N);
956 Add_One_Interp (N, Op_Id, Etype (Op_Id));
960 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
962 while Present (Op_Id) loop
963 if Ekind (Op_Id) = E_Operator then
964 Find_Concatenation_Types (L, R, Op_Id, N);
966 Analyze_User_Defined_Binary_Op (N, Op_Id);
969 Op_Id := Homonym (Op_Id);
974 end Analyze_Concatenation;
976 ------------------------------------
977 -- Analyze_Conditional_Expression --
978 ------------------------------------
980 procedure Analyze_Conditional_Expression (N : Node_Id) is
981 Condition : constant Node_Id := First (Expressions (N));
982 Then_Expr : constant Node_Id := Next (Condition);
983 Else_Expr : constant Node_Id := Next (Then_Expr);
986 Analyze_Expression (Condition);
987 Analyze_Expression (Then_Expr);
988 Analyze_Expression (Else_Expr);
989 Set_Etype (N, Etype (Then_Expr));
990 end Analyze_Conditional_Expression;
992 -------------------------
993 -- Analyze_Equality_Op --
994 -------------------------
996 procedure Analyze_Equality_Op (N : Node_Id) is
997 Loc : constant Source_Ptr := Sloc (N);
998 L : constant Node_Id := Left_Opnd (N);
999 R : constant Node_Id := Right_Opnd (N);
1003 Set_Etype (N, Any_Type);
1004 Candidate_Type := Empty;
1006 Analyze_Expression (L);
1007 Analyze_Expression (R);
1009 -- If the entity is set, the node is a generic instance with a non-local
1010 -- reference to the predefined operator or to a user-defined function.
1011 -- It can also be an inequality that is expanded into the negation of a
1012 -- call to a user-defined equality operator.
1014 -- For the predefined case, the result is Boolean, regardless of the
1015 -- type of the operands. The operands may even be limited, if they are
1016 -- generic actuals. If they are overloaded, label the left argument with
1017 -- the common type that must be present, or with the type of the formal
1018 -- of the user-defined function.
1020 if Present (Entity (N)) then
1022 Op_Id := Entity (N);
1024 if Ekind (Op_Id) = E_Operator then
1025 Add_One_Interp (N, Op_Id, Standard_Boolean);
1027 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1030 if Is_Overloaded (L) then
1032 if Ekind (Op_Id) = E_Operator then
1033 Set_Etype (L, Intersect_Types (L, R));
1035 Set_Etype (L, Etype (First_Formal (Op_Id)));
1040 Op_Id := Get_Name_Entity_Id (Chars (N));
1042 while Present (Op_Id) loop
1044 if Ekind (Op_Id) = E_Operator then
1045 Find_Equality_Types (L, R, Op_Id, N);
1047 Analyze_User_Defined_Binary_Op (N, Op_Id);
1050 Op_Id := Homonym (Op_Id);
1054 -- If there was no match, and the operator is inequality, this may
1055 -- be a case where inequality has not been made explicit, as for
1056 -- tagged types. Analyze the node as the negation of an equality
1057 -- operation. This cannot be done earlier, because before analysis
1058 -- we cannot rule out the presence of an explicit inequality.
1060 if Etype (N) = Any_Type
1061 and then Nkind (N) = N_Op_Ne
1063 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1065 while Present (Op_Id) loop
1067 if Ekind (Op_Id) = E_Operator then
1068 Find_Equality_Types (L, R, Op_Id, N);
1070 Analyze_User_Defined_Binary_Op (N, Op_Id);
1073 Op_Id := Homonym (Op_Id);
1076 if Etype (N) /= Any_Type then
1077 Op_Id := Entity (N);
1083 Left_Opnd => Relocate_Node (Left_Opnd (N)),
1084 Right_Opnd => Relocate_Node (Right_Opnd (N)))));
1086 Set_Entity (Right_Opnd (N), Op_Id);
1092 end Analyze_Equality_Op;
1094 ----------------------------------
1095 -- Analyze_Explicit_Dereference --
1096 ----------------------------------
1098 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1099 Loc : constant Source_Ptr := Sloc (N);
1100 P : constant Node_Id := Prefix (N);
1106 function Is_Function_Type return Boolean;
1107 -- Check whether node may be interpreted as an implicit function call.
1109 function Is_Function_Type return Boolean is
1114 if not Is_Overloaded (N) then
1115 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1116 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1119 Get_First_Interp (N, I, It);
1121 while Present (It.Nam) loop
1122 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1123 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1128 Get_Next_Interp (I, It);
1133 end Is_Function_Type;
1137 Set_Etype (N, Any_Type);
1139 -- Test for remote access to subprogram type, and if so return
1140 -- after rewriting the original tree.
1142 if Remote_AST_E_Dereference (P) then
1146 -- Normal processing for other than remote access to subprogram type
1148 if not Is_Overloaded (P) then
1149 if Is_Access_Type (Etype (P)) then
1151 -- Set the Etype. We need to go thru Is_For_Access_Subtypes
1152 -- to avoid other problems caused by the Private_Subtype
1153 -- and it is safe to go to the Base_Type because this is the
1154 -- same as converting the access value to its Base_Type.
1157 DT : Entity_Id := Designated_Type (Etype (P));
1160 if Ekind (DT) = E_Private_Subtype
1161 and then Is_For_Access_Subtype (DT)
1163 DT := Base_Type (DT);
1169 elsif Etype (P) /= Any_Type then
1170 Error_Msg_N ("prefix of dereference must be an access type", N);
1175 Get_First_Interp (P, I, It);
1177 while Present (It.Nam) loop
1180 if Is_Access_Type (T) then
1181 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1184 Get_Next_Interp (I, It);
1189 -- Error if no interpretation of the prefix has an access type.
1191 if Etype (N) = Any_Type then
1193 ("access type required in prefix of explicit dereference", P);
1194 Set_Etype (N, Any_Type);
1200 and then Nkind (Parent (N)) /= N_Indexed_Component
1202 and then (Nkind (Parent (N)) /= N_Function_Call
1203 or else N /= Name (Parent (N)))
1205 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1206 or else N /= Name (Parent (N)))
1208 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1209 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1211 (Attribute_Name (Parent (N)) /= Name_Address
1213 Attribute_Name (Parent (N)) /= Name_Access))
1215 -- Name is a function call with no actuals, in a context that
1216 -- requires deproceduring (including as an actual in an enclosing
1217 -- function or procedure call). We can conceive of pathological cases
1218 -- where the prefix might include functions that return access to
1219 -- subprograms and others that return a regular type. Disambiguation
1220 -- of those will have to take place in Resolve. See e.g. 7117-014.
1223 Make_Function_Call (Loc,
1224 Name => Make_Explicit_Dereference (Loc, P),
1225 Parameter_Associations => New_List);
1227 -- If the prefix is overloaded, remove operations that have formals,
1228 -- we know that this is a parameterless call.
1230 if Is_Overloaded (P) then
1231 Get_First_Interp (P, I, It);
1233 while Present (It.Nam) loop
1236 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1242 Get_Next_Interp (I, It);
1250 -- A value of remote access-to-class-wide must not be dereferenced
1253 Validate_Remote_Access_To_Class_Wide_Type (N);
1255 end Analyze_Explicit_Dereference;
1257 ------------------------
1258 -- Analyze_Expression --
1259 ------------------------
1261 procedure Analyze_Expression (N : Node_Id) is
1264 Check_Parameterless_Call (N);
1265 end Analyze_Expression;
1267 ------------------------------------
1268 -- Analyze_Indexed_Component_Form --
1269 ------------------------------------
1271 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1272 P : constant Node_Id := Prefix (N);
1273 Exprs : constant List_Id := Expressions (N);
1279 procedure Process_Function_Call;
1280 -- Prefix in indexed component form is an overloadable entity,
1281 -- so the node is a function call. Reformat it as such.
1283 procedure Process_Indexed_Component;
1284 -- Prefix in indexed component form is actually an indexed component.
1285 -- This routine processes it, knowing that the prefix is already
1288 procedure Process_Indexed_Component_Or_Slice;
1289 -- An indexed component with a single index may designate a slice if
1290 -- the index is a subtype mark. This routine disambiguates these two
1291 -- cases by resolving the prefix to see if it is a subtype mark.
1293 procedure Process_Overloaded_Indexed_Component;
1294 -- If the prefix of an indexed component is overloaded, the proper
1295 -- interpretation is selected by the index types and the context.
1297 ---------------------------
1298 -- Process_Function_Call --
1299 ---------------------------
1301 procedure Process_Function_Call is
1305 Change_Node (N, N_Function_Call);
1307 Set_Parameter_Associations (N, Exprs);
1308 Actual := First (Parameter_Associations (N));
1310 while Present (Actual) loop
1312 Check_Parameterless_Call (Actual);
1313 Next_Actual (Actual);
1317 end Process_Function_Call;
1319 -------------------------------
1320 -- Process_Indexed_Component --
1321 -------------------------------
1323 procedure Process_Indexed_Component is
1325 Array_Type : Entity_Id;
1327 Entry_Family : Entity_Id;
1330 Exp := First (Exprs);
1332 if Is_Overloaded (P) then
1333 Process_Overloaded_Indexed_Component;
1336 Array_Type := Etype (P);
1338 -- Prefix must be appropriate for an array type.
1339 -- Dereference the prefix if it is an access type.
1341 if Is_Access_Type (Array_Type) then
1342 Array_Type := Designated_Type (Array_Type);
1343 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1346 if Is_Array_Type (Array_Type) then
1349 elsif (Is_Entity_Name (P)
1351 Ekind (Entity (P)) = E_Entry_Family)
1353 (Nkind (P) = N_Selected_Component
1355 Is_Entity_Name (Selector_Name (P))
1357 Ekind (Entity (Selector_Name (P))) = E_Entry_Family)
1359 if Is_Entity_Name (P) then
1360 Entry_Family := Entity (P);
1362 Entry_Family := Entity (Selector_Name (P));
1366 Set_Etype (N, Any_Type);
1368 if not Has_Compatible_Type
1369 (Exp, Entry_Index_Type (Entry_Family))
1371 Error_Msg_N ("invalid index type in entry name", N);
1373 elsif Present (Next (Exp)) then
1374 Error_Msg_N ("too many subscripts in entry reference", N);
1377 Set_Etype (N, Etype (P));
1382 elsif Is_Record_Type (Array_Type)
1383 and then Remote_AST_I_Dereference (P)
1387 elsif Array_Type = Any_Type then
1388 Set_Etype (N, Any_Type);
1391 -- Here we definitely have a bad indexing
1394 if Nkind (Parent (N)) = N_Requeue_Statement
1396 ((Is_Entity_Name (P)
1397 and then Ekind (Entity (P)) = E_Entry)
1399 (Nkind (P) = N_Selected_Component
1400 and then Is_Entity_Name (Selector_Name (P))
1401 and then Ekind (Entity (Selector_Name (P))) = E_Entry))
1404 ("REQUEUE does not permit parameters", First (Exprs));
1406 elsif Is_Entity_Name (P)
1407 and then Etype (P) = Standard_Void_Type
1409 Error_Msg_NE ("incorrect use of&", P, Entity (P));
1412 Error_Msg_N ("array type required in indexed component", P);
1415 Set_Etype (N, Any_Type);
1419 Index := First_Index (Array_Type);
1421 while Present (Index) and then Present (Exp) loop
1422 if not Has_Compatible_Type (Exp, Etype (Index)) then
1423 Wrong_Type (Exp, Etype (Index));
1424 Set_Etype (N, Any_Type);
1432 Set_Etype (N, Component_Type (Array_Type));
1434 if Present (Index) then
1436 ("too few subscripts in array reference", First (Exprs));
1438 elsif Present (Exp) then
1439 Error_Msg_N ("too many subscripts in array reference", Exp);
1443 end Process_Indexed_Component;
1445 ----------------------------------------
1446 -- Process_Indexed_Component_Or_Slice --
1447 ----------------------------------------
1449 procedure Process_Indexed_Component_Or_Slice is
1451 Exp := First (Exprs);
1453 while Present (Exp) loop
1454 Analyze_Expression (Exp);
1458 Exp := First (Exprs);
1460 -- If one index is present, and it is a subtype name, then the
1461 -- node denotes a slice (note that the case of an explicit range
1462 -- for a slice was already built as an N_Slice node in the first
1463 -- place, so that case is not handled here).
1465 -- We use a replace rather than a rewrite here because this is one
1466 -- of the cases in which the tree built by the parser is plain wrong.
1469 and then Is_Entity_Name (Exp)
1470 and then Is_Type (Entity (Exp))
1473 Make_Slice (Sloc (N),
1475 Discrete_Range => New_Copy (Exp)));
1478 -- Otherwise (more than one index present, or single index is not
1479 -- a subtype name), then we have the indexed component case.
1482 Process_Indexed_Component;
1484 end Process_Indexed_Component_Or_Slice;
1486 ------------------------------------------
1487 -- Process_Overloaded_Indexed_Component --
1488 ------------------------------------------
1490 procedure Process_Overloaded_Indexed_Component is
1499 Set_Etype (N, Any_Type);
1500 Get_First_Interp (P, I, It);
1502 while Present (It.Nam) loop
1505 if Is_Access_Type (Typ) then
1506 Typ := Designated_Type (Typ);
1507 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1510 if Is_Array_Type (Typ) then
1512 -- Got a candidate: verify that index types are compatible
1514 Index := First_Index (Typ);
1517 Exp := First (Exprs);
1519 while Present (Index) and then Present (Exp) loop
1520 if Has_Compatible_Type (Exp, Etype (Index)) then
1532 if Found and then No (Index) and then No (Exp) then
1534 Etype (Component_Type (Typ)),
1535 Etype (Component_Type (Typ)));
1539 Get_Next_Interp (I, It);
1542 if Etype (N) = Any_Type then
1543 Error_Msg_N ("no legal interpetation for indexed component", N);
1544 Set_Is_Overloaded (N, False);
1548 end Process_Overloaded_Indexed_Component;
1550 ------------------------------------
1551 -- Analyze_Indexed_Component_Form --
1552 ------------------------------------
1555 -- Get name of array, function or type
1558 if Nkind (N) = N_Function_Call
1559 or else Nkind (N) = N_Procedure_Call_Statement
1561 -- If P is an explicit dereference whose prefix is of a
1562 -- remote access-to-subprogram type, then N has already
1563 -- been rewritten as a subprogram call and analyzed.
1568 pragma Assert (Nkind (N) = N_Indexed_Component);
1570 P_T := Base_Type (Etype (P));
1572 if Is_Entity_Name (P)
1573 or else Nkind (P) = N_Operator_Symbol
1577 if Ekind (U_N) in Type_Kind then
1579 -- Reformat node as a type conversion.
1581 E := Remove_Head (Exprs);
1583 if Present (First (Exprs)) then
1585 ("argument of type conversion must be single expression", N);
1588 Change_Node (N, N_Type_Conversion);
1589 Set_Subtype_Mark (N, P);
1591 Set_Expression (N, E);
1593 -- After changing the node, call for the specific Analysis
1594 -- routine directly, to avoid a double call to the expander.
1596 Analyze_Type_Conversion (N);
1600 if Is_Overloadable (U_N) then
1601 Process_Function_Call;
1603 elsif Ekind (Etype (P)) = E_Subprogram_Type
1604 or else (Is_Access_Type (Etype (P))
1606 Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type)
1608 -- Call to access_to-subprogram with possible implicit dereference
1610 Process_Function_Call;
1612 elsif Is_Generic_Subprogram (U_N) then
1614 -- A common beginner's (or C++ templates fan) error.
1616 Error_Msg_N ("generic subprogram cannot be called", N);
1617 Set_Etype (N, Any_Type);
1621 Process_Indexed_Component_Or_Slice;
1624 -- If not an entity name, prefix is an expression that may denote
1625 -- an array or an access-to-subprogram.
1628 if Ekind (P_T) = E_Subprogram_Type
1629 or else (Is_Access_Type (P_T)
1631 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
1633 Process_Function_Call;
1635 elsif Nkind (P) = N_Selected_Component
1636 and then Ekind (Entity (Selector_Name (P))) = E_Function
1638 Process_Function_Call;
1641 -- Indexed component, slice, or a call to a member of a family
1642 -- entry, which will be converted to an entry call later.
1644 Process_Indexed_Component_Or_Slice;
1647 end Analyze_Indexed_Component_Form;
1649 ------------------------
1650 -- Analyze_Logical_Op --
1651 ------------------------
1653 procedure Analyze_Logical_Op (N : Node_Id) is
1654 L : constant Node_Id := Left_Opnd (N);
1655 R : constant Node_Id := Right_Opnd (N);
1656 Op_Id : Entity_Id := Entity (N);
1659 Set_Etype (N, Any_Type);
1660 Candidate_Type := Empty;
1662 Analyze_Expression (L);
1663 Analyze_Expression (R);
1665 if Present (Op_Id) then
1667 if Ekind (Op_Id) = E_Operator then
1668 Find_Boolean_Types (L, R, Op_Id, N);
1670 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1674 Op_Id := Get_Name_Entity_Id (Chars (N));
1676 while Present (Op_Id) loop
1677 if Ekind (Op_Id) = E_Operator then
1678 Find_Boolean_Types (L, R, Op_Id, N);
1680 Analyze_User_Defined_Binary_Op (N, Op_Id);
1683 Op_Id := Homonym (Op_Id);
1688 end Analyze_Logical_Op;
1690 ---------------------------
1691 -- Analyze_Membership_Op --
1692 ---------------------------
1694 procedure Analyze_Membership_Op (N : Node_Id) is
1695 L : constant Node_Id := Left_Opnd (N);
1696 R : constant Node_Id := Right_Opnd (N);
1698 Index : Interp_Index;
1700 Found : Boolean := False;
1704 procedure Try_One_Interp (T1 : Entity_Id);
1705 -- Routine to try one proposed interpretation. Note that the context
1706 -- of the operation plays no role in resolving the arguments, so that
1707 -- if there is more than one interpretation of the operands that is
1708 -- compatible with a membership test, the operation is ambiguous.
1710 procedure Try_One_Interp (T1 : Entity_Id) is
1712 if Has_Compatible_Type (R, T1) then
1714 and then Base_Type (T1) /= Base_Type (T_F)
1716 It := Disambiguate (L, I_F, Index, Any_Type);
1718 if It = No_Interp then
1719 Ambiguous_Operands (N);
1720 Set_Etype (L, Any_Type);
1738 -- Start of processing for Analyze_Membership_Op
1741 Analyze_Expression (L);
1743 if Nkind (R) = N_Range
1744 or else (Nkind (R) = N_Attribute_Reference
1745 and then Attribute_Name (R) = Name_Range)
1749 if not Is_Overloaded (L) then
1750 Try_One_Interp (Etype (L));
1753 Get_First_Interp (L, Index, It);
1755 while Present (It.Typ) loop
1756 Try_One_Interp (It.Typ);
1757 Get_Next_Interp (Index, It);
1761 -- If not a range, it can only be a subtype mark, or else there
1762 -- is a more basic error, to be diagnosed in Find_Type.
1767 if Is_Entity_Name (R) then
1768 Check_Fully_Declared (Entity (R), R);
1772 -- Compatibility between expression and subtype mark or range is
1773 -- checked during resolution. The result of the operation is Boolean
1776 Set_Etype (N, Standard_Boolean);
1777 end Analyze_Membership_Op;
1779 ----------------------
1780 -- Analyze_Negation --
1781 ----------------------
1783 procedure Analyze_Negation (N : Node_Id) is
1784 R : constant Node_Id := Right_Opnd (N);
1785 Op_Id : Entity_Id := Entity (N);
1788 Set_Etype (N, Any_Type);
1789 Candidate_Type := Empty;
1791 Analyze_Expression (R);
1793 if Present (Op_Id) then
1794 if Ekind (Op_Id) = E_Operator then
1795 Find_Negation_Types (R, Op_Id, N);
1797 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1801 Op_Id := Get_Name_Entity_Id (Chars (N));
1803 while Present (Op_Id) loop
1804 if Ekind (Op_Id) = E_Operator then
1805 Find_Negation_Types (R, Op_Id, N);
1807 Analyze_User_Defined_Unary_Op (N, Op_Id);
1810 Op_Id := Homonym (Op_Id);
1815 end Analyze_Negation;
1821 procedure Analyze_Null (N : Node_Id) is
1823 Set_Etype (N, Any_Access);
1826 ----------------------
1827 -- Analyze_One_Call --
1828 ----------------------
1830 procedure Analyze_One_Call
1834 Success : out Boolean)
1836 Actuals : constant List_Id := Parameter_Associations (N);
1837 Prev_T : constant Entity_Id := Etype (N);
1840 Is_Indexed : Boolean := False;
1841 Subp_Type : constant Entity_Id := Etype (Nam);
1844 procedure Indicate_Name_And_Type;
1845 -- If candidate interpretation matches, indicate name and type of
1846 -- result on call node.
1848 ----------------------------
1849 -- Indicate_Name_And_Type --
1850 ----------------------------
1852 procedure Indicate_Name_And_Type is
1854 Add_One_Interp (N, Nam, Etype (Nam));
1857 -- If the prefix of the call is a name, indicate the entity
1858 -- being called. If it is not a name, it is an expression that
1859 -- denotes an access to subprogram or else an entry or family. In
1860 -- the latter case, the name is a selected component, and the entity
1861 -- being called is noted on the selector.
1863 if not Is_Type (Nam) then
1864 if Is_Entity_Name (Name (N))
1865 or else Nkind (Name (N)) = N_Operator_Symbol
1867 Set_Entity (Name (N), Nam);
1869 elsif Nkind (Name (N)) = N_Selected_Component then
1870 Set_Entity (Selector_Name (Name (N)), Nam);
1874 if Debug_Flag_E and not Report then
1875 Write_Str (" Overloaded call ");
1876 Write_Int (Int (N));
1877 Write_Str (" compatible with ");
1878 Write_Int (Int (Nam));
1881 end Indicate_Name_And_Type;
1883 -- Start of processing for Analyze_One_Call
1888 -- If the subprogram has no formals, or if all the formals have
1889 -- defaults, and the return type is an array type, the node may
1890 -- denote an indexing of the result of a parameterless call.
1892 if Needs_No_Actuals (Nam)
1893 and then Present (Actuals)
1895 if Is_Array_Type (Subp_Type) then
1896 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type);
1898 elsif Is_Access_Type (Subp_Type)
1899 and then Is_Array_Type (Designated_Type (Subp_Type))
1902 Try_Indexed_Call (N, Nam, Designated_Type (Subp_Type));
1904 elsif Is_Access_Type (Subp_Type)
1905 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
1907 Is_Indexed := Try_Indirect_Call (N, Nam, Subp_Type);
1912 Normalize_Actuals (N, Nam, (Report and not Is_Indexed), Norm_OK);
1916 -- Mismatch in number or names of parameters
1918 if Debug_Flag_E then
1919 Write_Str (" normalization fails in call ");
1920 Write_Int (Int (N));
1921 Write_Str (" with subprogram ");
1922 Write_Int (Int (Nam));
1926 -- If the context expects a function call, discard any interpretation
1927 -- that is a procedure. If the node is not overloaded, leave as is for
1928 -- better error reporting when type mismatch is found.
1930 elsif Nkind (N) = N_Function_Call
1931 and then Is_Overloaded (Name (N))
1932 and then Ekind (Nam) = E_Procedure
1936 -- Ditto for function calls in a procedure context.
1938 elsif Nkind (N) = N_Procedure_Call_Statement
1939 and then Is_Overloaded (Name (N))
1940 and then Etype (Nam) /= Standard_Void_Type
1944 elsif not Present (Actuals) then
1946 -- If Normalize succeeds, then there are default parameters for
1949 Indicate_Name_And_Type;
1951 elsif Ekind (Nam) = E_Operator then
1952 if Nkind (N) = N_Procedure_Call_Statement then
1956 -- This can occur when the prefix of the call is an operator
1957 -- name or an expanded name whose selector is an operator name.
1959 Analyze_Operator_Call (N, Nam);
1961 if Etype (N) /= Prev_T then
1963 -- There may be a user-defined operator that hides the
1964 -- current interpretation. We must check for this independently
1965 -- of the analysis of the call with the user-defined operation,
1966 -- because the parameter names may be wrong and yet the hiding
1967 -- takes place. Fixes b34014o.
1969 if Is_Overloaded (Name (N)) then
1975 Get_First_Interp (Name (N), I, It);
1977 while Present (It.Nam) loop
1979 if Ekind (It.Nam) /= E_Operator
1980 and then Hides_Op (It.Nam, Nam)
1983 (First_Actual (N), Etype (First_Formal (It.Nam)))
1984 and then (No (Next_Actual (First_Actual (N)))
1985 or else Has_Compatible_Type
1986 (Next_Actual (First_Actual (N)),
1987 Etype (Next_Formal (First_Formal (It.Nam)))))
1989 Set_Etype (N, Prev_T);
1993 Get_Next_Interp (I, It);
1998 -- If operator matches formals, record its name on the call.
1999 -- If the operator is overloaded, Resolve will select the
2000 -- correct one from the list of interpretations. The call
2001 -- node itself carries the first candidate.
2003 Set_Entity (Name (N), Nam);
2006 elsif Report and then Etype (N) = Any_Type then
2007 Error_Msg_N ("incompatible arguments for operator", N);
2011 -- Normalize_Actuals has chained the named associations in the
2012 -- correct order of the formals.
2014 Actual := First_Actual (N);
2015 Formal := First_Formal (Nam);
2017 while Present (Actual) and then Present (Formal) loop
2019 if Nkind (Parent (Actual)) /= N_Parameter_Association
2020 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2022 if Has_Compatible_Type (Actual, Etype (Formal)) then
2023 Next_Actual (Actual);
2024 Next_Formal (Formal);
2027 if Debug_Flag_E then
2028 Write_Str (" type checking fails in call ");
2029 Write_Int (Int (N));
2030 Write_Str (" with formal ");
2031 Write_Int (Int (Formal));
2032 Write_Str (" in subprogram ");
2033 Write_Int (Int (Nam));
2037 if Report and not Is_Indexed then
2039 Wrong_Type (Actual, Etype (Formal));
2041 if Nkind (Actual) = N_Op_Eq
2042 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2044 Formal := First_Formal (Nam);
2046 while Present (Formal) loop
2048 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2050 ("possible misspelling of `='>`!", Actual);
2054 Next_Formal (Formal);
2058 if All_Errors_Mode then
2059 Error_Msg_Sloc := Sloc (Nam);
2061 if Is_Overloadable (Nam)
2062 and then Present (Alias (Nam))
2063 and then not Comes_From_Source (Nam)
2066 (" =='> in call to &#(inherited)!", Actual, Nam);
2068 Error_Msg_NE (" =='> in call to &#!", Actual, Nam);
2077 -- Normalize_Actuals has verified that a default value exists
2078 -- for this formal. Current actual names a subsequent formal.
2080 Next_Formal (Formal);
2084 -- On exit, all actuals match.
2086 Indicate_Name_And_Type;
2088 end Analyze_One_Call;
2090 ----------------------------
2091 -- Analyze_Operator_Call --
2092 ----------------------------
2094 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2095 Op_Name : constant Name_Id := Chars (Op_Id);
2096 Act1 : constant Node_Id := First_Actual (N);
2097 Act2 : constant Node_Id := Next_Actual (Act1);
2100 if Present (Act2) then
2102 -- Maybe binary operators
2104 if Present (Next_Actual (Act2)) then
2106 -- Too many actuals for an operator
2110 elsif Op_Name = Name_Op_Add
2111 or else Op_Name = Name_Op_Subtract
2112 or else Op_Name = Name_Op_Multiply
2113 or else Op_Name = Name_Op_Divide
2114 or else Op_Name = Name_Op_Mod
2115 or else Op_Name = Name_Op_Rem
2116 or else Op_Name = Name_Op_Expon
2118 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2120 elsif Op_Name = Name_Op_And
2121 or else Op_Name = Name_Op_Or
2122 or else Op_Name = Name_Op_Xor
2124 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2126 elsif Op_Name = Name_Op_Lt
2127 or else Op_Name = Name_Op_Le
2128 or else Op_Name = Name_Op_Gt
2129 or else Op_Name = Name_Op_Ge
2131 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2133 elsif Op_Name = Name_Op_Eq
2134 or else Op_Name = Name_Op_Ne
2136 Find_Equality_Types (Act1, Act2, Op_Id, N);
2138 elsif Op_Name = Name_Op_Concat then
2139 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2141 -- Is this else null correct, or should it be an abort???
2150 if Op_Name = Name_Op_Subtract or else
2151 Op_Name = Name_Op_Add or else
2152 Op_Name = Name_Op_Abs
2154 Find_Unary_Types (Act1, Op_Id, N);
2157 Op_Name = Name_Op_Not
2159 Find_Negation_Types (Act1, Op_Id, N);
2161 -- Is this else null correct, or should it be an abort???
2167 end Analyze_Operator_Call;
2169 -------------------------------------------
2170 -- Analyze_Overloaded_Selected_Component --
2171 -------------------------------------------
2173 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
2174 Nam : constant Node_Id := Prefix (N);
2175 Sel : constant Node_Id := Selector_Name (N);
2182 Get_First_Interp (Nam, I, It);
2184 Set_Etype (Sel, Any_Type);
2186 while Present (It.Typ) loop
2187 if Is_Access_Type (It.Typ) then
2188 T := Designated_Type (It.Typ);
2189 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2195 if Is_Record_Type (T) then
2196 Comp := First_Entity (T);
2198 while Present (Comp) loop
2200 if Chars (Comp) = Chars (Sel)
2201 and then Is_Visible_Component (Comp)
2203 Set_Entity_With_Style_Check (Sel, Comp);
2204 Generate_Reference (Comp, Sel);
2206 Set_Etype (Sel, Etype (Comp));
2207 Add_One_Interp (N, Etype (Comp), Etype (Comp));
2209 -- This also specifies a candidate to resolve the name.
2210 -- Further overloading will be resolved from context.
2212 Set_Etype (Nam, It.Typ);
2218 elsif Is_Concurrent_Type (T) then
2219 Comp := First_Entity (T);
2221 while Present (Comp)
2222 and then Comp /= First_Private_Entity (T)
2224 if Chars (Comp) = Chars (Sel) then
2225 if Is_Overloadable (Comp) then
2226 Add_One_Interp (Sel, Comp, Etype (Comp));
2228 Set_Entity_With_Style_Check (Sel, Comp);
2229 Generate_Reference (Comp, Sel);
2232 Set_Etype (Sel, Etype (Comp));
2233 Set_Etype (N, Etype (Comp));
2234 Set_Etype (Nam, It.Typ);
2236 -- For access type case, introduce explicit deference for
2237 -- more uniform treatment of entry calls.
2239 if Is_Access_Type (Etype (Nam)) then
2240 Insert_Explicit_Dereference (Nam);
2242 (Warn_On_Dereference, "?implicit dereference", N);
2249 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2252 Get_Next_Interp (I, It);
2255 if Etype (N) = Any_Type then
2256 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
2257 Set_Entity (Sel, Any_Id);
2258 Set_Etype (Sel, Any_Type);
2261 end Analyze_Overloaded_Selected_Component;
2263 ----------------------------------
2264 -- Analyze_Qualified_Expression --
2265 ----------------------------------
2267 procedure Analyze_Qualified_Expression (N : Node_Id) is
2268 Mark : constant Entity_Id := Subtype_Mark (N);
2272 Set_Etype (N, Any_Type);
2276 if T = Any_Type then
2279 Check_Fully_Declared (T, N);
2281 Analyze_Expression (Expression (N));
2283 end Analyze_Qualified_Expression;
2289 procedure Analyze_Range (N : Node_Id) is
2290 L : constant Node_Id := Low_Bound (N);
2291 H : constant Node_Id := High_Bound (N);
2292 I1, I2 : Interp_Index;
2295 procedure Check_Common_Type (T1, T2 : Entity_Id);
2296 -- Verify the compatibility of two types, and choose the
2297 -- non universal one if the other is universal.
2299 procedure Check_High_Bound (T : Entity_Id);
2300 -- Test one interpretation of the low bound against all those
2301 -- of the high bound.
2303 procedure Check_Universal_Expression (N : Node_Id);
2304 -- In Ada83, reject bounds of a universal range that are not
2305 -- literals or entity names.
2307 -----------------------
2308 -- Check_Common_Type --
2309 -----------------------
2311 procedure Check_Common_Type (T1, T2 : Entity_Id) is
2313 if Covers (T1, T2) or else Covers (T2, T1) then
2314 if T1 = Universal_Integer
2315 or else T1 = Universal_Real
2316 or else T1 = Any_Character
2318 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
2321 Add_One_Interp (N, T1, T1);
2324 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
2327 end Check_Common_Type;
2329 ----------------------
2330 -- Check_High_Bound --
2331 ----------------------
2333 procedure Check_High_Bound (T : Entity_Id) is
2335 if not Is_Overloaded (H) then
2336 Check_Common_Type (T, Etype (H));
2338 Get_First_Interp (H, I2, It2);
2340 while Present (It2.Typ) loop
2341 Check_Common_Type (T, It2.Typ);
2342 Get_Next_Interp (I2, It2);
2345 end Check_High_Bound;
2347 -----------------------------
2348 -- Is_Universal_Expression --
2349 -----------------------------
2351 procedure Check_Universal_Expression (N : Node_Id) is
2353 if Etype (N) = Universal_Integer
2354 and then Nkind (N) /= N_Integer_Literal
2355 and then not Is_Entity_Name (N)
2356 and then Nkind (N) /= N_Attribute_Reference
2358 Error_Msg_N ("illegal bound in discrete range", N);
2360 end Check_Universal_Expression;
2362 -- Start of processing for Analyze_Range
2365 Set_Etype (N, Any_Type);
2366 Analyze_Expression (L);
2367 Analyze_Expression (H);
2369 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
2373 if not Is_Overloaded (L) then
2374 Check_High_Bound (Etype (L));
2376 Get_First_Interp (L, I1, It1);
2378 while Present (It1.Typ) loop
2379 Check_High_Bound (It1.Typ);
2380 Get_Next_Interp (I1, It1);
2384 -- If result is Any_Type, then we did not find a compatible pair
2386 if Etype (N) = Any_Type then
2387 Error_Msg_N ("incompatible types in range ", N);
2393 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
2394 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
2396 Check_Universal_Expression (L);
2397 Check_Universal_Expression (H);
2401 -----------------------
2402 -- Analyze_Reference --
2403 -----------------------
2405 procedure Analyze_Reference (N : Node_Id) is
2406 P : constant Node_Id := Prefix (N);
2407 Acc_Type : Entity_Id;
2411 Acc_Type := Create_Itype (E_Allocator_Type, N);
2412 Set_Etype (Acc_Type, Acc_Type);
2413 Init_Size_Align (Acc_Type);
2414 Set_Directly_Designated_Type (Acc_Type, Etype (P));
2415 Set_Etype (N, Acc_Type);
2416 end Analyze_Reference;
2418 --------------------------------
2419 -- Analyze_Selected_Component --
2420 --------------------------------
2422 -- Prefix is a record type or a task or protected type. In the
2423 -- later case, the selector must denote a visible entry.
2425 procedure Analyze_Selected_Component (N : Node_Id) is
2426 Name : constant Node_Id := Prefix (N);
2427 Sel : constant Node_Id := Selector_Name (N);
2429 Entity_List : Entity_Id;
2430 Prefix_Type : Entity_Id;
2435 -- Start of processing for Analyze_Selected_Component
2438 Set_Etype (N, Any_Type);
2440 if Is_Overloaded (Name) then
2441 Analyze_Overloaded_Selected_Component (N);
2444 elsif Etype (Name) = Any_Type then
2445 Set_Entity (Sel, Any_Id);
2446 Set_Etype (Sel, Any_Type);
2450 -- Function calls that are prefixes of selected components must be
2451 -- fully resolved in case we need to build an actual subtype, or
2452 -- do some other operation requiring a fully resolved prefix.
2454 -- Note: Resolving all Nkinds of nodes here doesn't work.
2455 -- (Breaks 2129-008) ???.
2457 if Nkind (Name) = N_Function_Call then
2461 Prefix_Type := Etype (Name);
2464 if Is_Access_Type (Prefix_Type) then
2466 -- A RACW object can never be used as prefix of a selected
2467 -- component since that means it is dereferenced without
2468 -- being a controlling operand of a dispatching operation
2471 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
2472 and then Comes_From_Source (N)
2475 ("invalid dereference of a remote access to class-wide value",
2478 -- Normal case of selected component applied to access type
2481 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2484 Prefix_Type := Designated_Type (Prefix_Type);
2487 if Ekind (Prefix_Type) = E_Private_Subtype then
2488 Prefix_Type := Base_Type (Prefix_Type);
2491 Entity_List := Prefix_Type;
2493 -- For class-wide types, use the entity list of the root type. This
2494 -- indirection is specially important for private extensions because
2495 -- only the root type get switched (not the class-wide type).
2497 if Is_Class_Wide_Type (Prefix_Type) then
2498 Entity_List := Root_Type (Prefix_Type);
2501 Comp := First_Entity (Entity_List);
2503 -- If the selector has an original discriminant, the node appears in
2504 -- an instance. Replace the discriminant with the corresponding one
2505 -- in the current discriminated type. For nested generics, this must
2506 -- be done transitively, so note the new original discriminant.
2508 if Nkind (Sel) = N_Identifier
2509 and then Present (Original_Discriminant (Sel))
2511 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
2513 -- Mark entity before rewriting, for completeness and because
2514 -- subsequent semantic checks might examine the original node.
2516 Set_Entity (Sel, Comp);
2517 Rewrite (Selector_Name (N),
2518 New_Occurrence_Of (Comp, Sloc (N)));
2519 Set_Original_Discriminant (Selector_Name (N), Comp);
2520 Set_Etype (N, Etype (Comp));
2522 if Is_Access_Type (Etype (Name)) then
2523 Insert_Explicit_Dereference (Name);
2524 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2527 elsif Is_Record_Type (Prefix_Type) then
2529 -- Find component with given name
2531 while Present (Comp) loop
2533 if Chars (Comp) = Chars (Sel)
2534 and then Is_Visible_Component (Comp)
2536 Set_Entity_With_Style_Check (Sel, Comp);
2537 Generate_Reference (Comp, Sel);
2539 Set_Etype (Sel, Etype (Comp));
2541 if Ekind (Comp) = E_Discriminant then
2542 if Is_Unchecked_Union (Prefix_Type) then
2544 ("cannot reference discriminant of Unchecked_Union",
2548 if Is_Generic_Type (Prefix_Type)
2550 Is_Generic_Type (Root_Type (Prefix_Type))
2552 Set_Original_Discriminant (Sel, Comp);
2556 -- Resolve the prefix early otherwise it is not possible to
2557 -- build the actual subtype of the component: it may need
2558 -- to duplicate this prefix and duplication is only allowed
2559 -- on fully resolved expressions.
2563 -- We never need an actual subtype for the case of a selection
2564 -- for a indexed component of a non-packed array, since in
2565 -- this case gigi generates all the checks and can find the
2566 -- necessary bounds information.
2568 -- We also do not need an actual subtype for the case of
2569 -- a first, last, length, or range attribute applied to a
2570 -- non-packed array, since gigi can again get the bounds in
2571 -- these cases (gigi cannot handle the packed case, since it
2572 -- has the bounds of the packed array type, not the original
2573 -- bounds of the type). However, if the prefix is itself a
2574 -- selected component, as in a.b.c (i), gigi may regard a.b.c
2575 -- as a dynamic-sized temporary, so we do generate an actual
2576 -- subtype for this case.
2578 Parent_N := Parent (N);
2580 if not Is_Packed (Etype (Comp))
2582 ((Nkind (Parent_N) = N_Indexed_Component
2583 and then Nkind (Name) /= N_Selected_Component)
2585 (Nkind (Parent_N) = N_Attribute_Reference
2586 and then (Attribute_Name (Parent_N) = Name_First
2588 Attribute_Name (Parent_N) = Name_Last
2590 Attribute_Name (Parent_N) = Name_Length
2592 Attribute_Name (Parent_N) = Name_Range)))
2594 Set_Etype (N, Etype (Comp));
2596 -- In all other cases, we currently build an actual subtype. It
2597 -- seems likely that many of these cases can be avoided, but
2598 -- right now, the front end makes direct references to the
2599 -- bounds (e.g. in generating a length check), and if we do
2600 -- not make an actual subtype, we end up getting a direct
2601 -- reference to a discriminant which will not do.
2605 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
2606 Insert_Action (N, Act_Decl);
2608 if No (Act_Decl) then
2609 Set_Etype (N, Etype (Comp));
2612 -- Component type depends on discriminants. Enter the
2613 -- main attributes of the subtype.
2616 Subt : constant Entity_Id :=
2617 Defining_Identifier (Act_Decl);
2620 Set_Etype (Subt, Base_Type (Etype (Comp)));
2621 Set_Ekind (Subt, Ekind (Etype (Comp)));
2622 Set_Etype (N, Subt);
2633 elsif Is_Private_Type (Prefix_Type) then
2635 -- Allow access only to discriminants of the type. If the
2636 -- type has no full view, gigi uses the parent type for
2637 -- the components, so we do the same here.
2639 if No (Full_View (Prefix_Type)) then
2640 Entity_List := Root_Type (Base_Type (Prefix_Type));
2641 Comp := First_Entity (Entity_List);
2644 while Present (Comp) loop
2646 if Chars (Comp) = Chars (Sel) then
2647 if Ekind (Comp) = E_Discriminant then
2648 Set_Entity_With_Style_Check (Sel, Comp);
2649 Generate_Reference (Comp, Sel);
2651 Set_Etype (Sel, Etype (Comp));
2652 Set_Etype (N, Etype (Comp));
2654 if Is_Generic_Type (Prefix_Type)
2656 Is_Generic_Type (Root_Type (Prefix_Type))
2658 Set_Original_Discriminant (Sel, Comp);
2663 ("invisible selector for }",
2664 N, First_Subtype (Prefix_Type));
2665 Set_Entity (Sel, Any_Id);
2666 Set_Etype (N, Any_Type);
2675 elsif Is_Concurrent_Type (Prefix_Type) then
2677 -- Prefix is concurrent type. Find visible operation with given name
2678 -- For a task, this can only include entries or discriminants if
2679 -- the task type is not an enclosing scope. If it is an enclosing
2680 -- scope (e.g. in an inner task) then all entities are visible, but
2681 -- the prefix must denote the enclosing scope, i.e. can only be
2682 -- a direct name or an expanded name.
2684 Set_Etype (Sel, Any_Type);
2685 In_Scope := In_Open_Scopes (Prefix_Type);
2687 while Present (Comp) loop
2688 if Chars (Comp) = Chars (Sel) then
2689 if Is_Overloadable (Comp) then
2690 Add_One_Interp (Sel, Comp, Etype (Comp));
2692 elsif Ekind (Comp) = E_Discriminant
2693 or else Ekind (Comp) = E_Entry_Family
2695 and then Is_Entity_Name (Name))
2697 Set_Entity_With_Style_Check (Sel, Comp);
2698 Generate_Reference (Comp, Sel);
2704 Set_Etype (Sel, Etype (Comp));
2705 Set_Etype (N, Etype (Comp));
2707 if Ekind (Comp) = E_Discriminant then
2708 Set_Original_Discriminant (Sel, Comp);
2711 -- For access type case, introduce explicit deference for
2712 -- more uniform treatment of entry calls.
2714 if Is_Access_Type (Etype (Name)) then
2715 Insert_Explicit_Dereference (Name);
2717 (Warn_On_Dereference, "?implicit dereference", N);
2723 exit when not In_Scope
2724 and then Comp = First_Private_Entity (Prefix_Type);
2727 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2732 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
2735 -- If N still has no type, the component is not defined in the prefix.
2737 if Etype (N) = Any_Type then
2739 -- If the prefix is a single concurrent object, use its name in
2740 -- the error message, rather than that of its anonymous type.
2742 if Is_Concurrent_Type (Prefix_Type)
2743 and then Is_Internal_Name (Chars (Prefix_Type))
2744 and then not Is_Derived_Type (Prefix_Type)
2745 and then Is_Entity_Name (Name)
2748 Error_Msg_Node_2 := Entity (Name);
2749 Error_Msg_NE ("no selector& for&", N, Sel);
2751 Check_Misspelled_Selector (Entity_List, Sel);
2753 elsif Is_Generic_Type (Prefix_Type)
2754 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
2755 and then Prefix_Type /= Etype (Prefix_Type)
2756 and then Is_Record_Type (Etype (Prefix_Type))
2758 -- If this is a derived formal type, the parent may have a
2759 -- different visibility at this point. Try for an inherited
2760 -- component before reporting an error.
2762 Set_Etype (Prefix (N), Etype (Prefix_Type));
2763 Analyze_Selected_Component (N);
2766 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
2767 and then Is_Generic_Actual_Type (Prefix_Type)
2768 and then Present (Full_View (Prefix_Type))
2770 -- Similarly, if this the actual for a formal derived type,
2771 -- the component inherited from the generic parent may not
2772 -- be visible in the actual, but the selected component is
2779 First_Component (Generic_Parent_Type (Parent (Prefix_Type)));
2781 while Present (Comp) loop
2782 if Chars (Comp) = Chars (Sel) then
2783 Set_Entity_With_Style_Check (Sel, Comp);
2784 Set_Etype (Sel, Etype (Comp));
2785 Set_Etype (N, Etype (Comp));
2789 Next_Component (Comp);
2792 pragma Assert (Etype (N) /= Any_Type);
2796 if Ekind (Prefix_Type) = E_Record_Subtype then
2798 -- Check whether this is a component of the base type
2799 -- which is absent from a statically constrained subtype.
2800 -- This will raise constraint error at run-time, but is
2801 -- not a compile-time error. When the selector is illegal
2802 -- for base type as well fall through and generate a
2803 -- compilation error anyway.
2805 Comp := First_Component (Base_Type (Prefix_Type));
2807 while Present (Comp) loop
2809 if Chars (Comp) = Chars (Sel)
2810 and then Is_Visible_Component (Comp)
2812 Set_Entity_With_Style_Check (Sel, Comp);
2813 Generate_Reference (Comp, Sel);
2814 Set_Etype (Sel, Etype (Comp));
2815 Set_Etype (N, Etype (Comp));
2817 -- Emit appropriate message. Gigi will replace the
2818 -- node subsequently with the appropriate Raise.
2820 Apply_Compile_Time_Constraint_Error
2821 (N, "component not present in }?",
2822 CE_Discriminant_Check_Failed,
2823 Ent => Prefix_Type, Rep => False);
2824 Set_Raises_Constraint_Error (N);
2828 Next_Component (Comp);
2833 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
2834 Error_Msg_NE ("no selector& for}", N, Sel);
2836 Check_Misspelled_Selector (Entity_List, Sel);
2840 Set_Entity (Sel, Any_Id);
2841 Set_Etype (Sel, Any_Type);
2843 end Analyze_Selected_Component;
2845 ---------------------------
2846 -- Analyze_Short_Circuit --
2847 ---------------------------
2849 procedure Analyze_Short_Circuit (N : Node_Id) is
2850 L : constant Node_Id := Left_Opnd (N);
2851 R : constant Node_Id := Right_Opnd (N);
2856 Analyze_Expression (L);
2857 Analyze_Expression (R);
2858 Set_Etype (N, Any_Type);
2860 if not Is_Overloaded (L) then
2862 if Root_Type (Etype (L)) = Standard_Boolean
2863 and then Has_Compatible_Type (R, Etype (L))
2865 Add_One_Interp (N, Etype (L), Etype (L));
2869 Get_First_Interp (L, Ind, It);
2871 while Present (It.Typ) loop
2872 if Root_Type (It.Typ) = Standard_Boolean
2873 and then Has_Compatible_Type (R, It.Typ)
2875 Add_One_Interp (N, It.Typ, It.Typ);
2878 Get_Next_Interp (Ind, It);
2882 -- Here we have failed to find an interpretation. Clearly we
2883 -- know that it is not the case that both operands can have
2884 -- an interpretation of Boolean, but this is by far the most
2885 -- likely intended interpretation. So we simply resolve both
2886 -- operands as Booleans, and at least one of these resolutions
2887 -- will generate an error message, and we do not need to give
2888 -- a further error message on the short circuit operation itself.
2890 if Etype (N) = Any_Type then
2891 Resolve (L, Standard_Boolean);
2892 Resolve (R, Standard_Boolean);
2893 Set_Etype (N, Standard_Boolean);
2895 end Analyze_Short_Circuit;
2901 procedure Analyze_Slice (N : Node_Id) is
2902 P : constant Node_Id := Prefix (N);
2903 D : constant Node_Id := Discrete_Range (N);
2904 Array_Type : Entity_Id;
2906 procedure Analyze_Overloaded_Slice;
2907 -- If the prefix is overloaded, select those interpretations that
2908 -- yield a one-dimensional array type.
2910 procedure Analyze_Overloaded_Slice is
2916 Set_Etype (N, Any_Type);
2917 Get_First_Interp (P, I, It);
2919 while Present (It.Nam) loop
2922 if Is_Access_Type (Typ) then
2923 Typ := Designated_Type (Typ);
2924 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2927 if Is_Array_Type (Typ)
2928 and then Number_Dimensions (Typ) = 1
2929 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
2931 Add_One_Interp (N, Typ, Typ);
2934 Get_Next_Interp (I, It);
2937 if Etype (N) = Any_Type then
2938 Error_Msg_N ("expect array type in prefix of slice", N);
2940 end Analyze_Overloaded_Slice;
2942 -- Start of processing for Analyze_Slice
2945 -- Analyze the prefix if not done already
2947 if No (Etype (P)) then
2953 if Is_Overloaded (P) then
2954 Analyze_Overloaded_Slice;
2957 Array_Type := Etype (P);
2958 Set_Etype (N, Any_Type);
2960 if Is_Access_Type (Array_Type) then
2961 Array_Type := Designated_Type (Array_Type);
2962 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2965 if not Is_Array_Type (Array_Type) then
2966 Wrong_Type (P, Any_Array);
2968 elsif Number_Dimensions (Array_Type) > 1 then
2970 ("type is not one-dimensional array in slice prefix", N);
2973 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
2975 Wrong_Type (D, Etype (First_Index (Array_Type)));
2978 Set_Etype (N, Array_Type);
2983 -----------------------------
2984 -- Analyze_Type_Conversion --
2985 -----------------------------
2987 procedure Analyze_Type_Conversion (N : Node_Id) is
2988 Expr : constant Node_Id := Expression (N);
2992 -- If Conversion_OK is set, then the Etype is already set, and the
2993 -- only processing required is to analyze the expression. This is
2994 -- used to construct certain "illegal" conversions which are not
2995 -- allowed by Ada semantics, but can be handled OK by Gigi, see
2996 -- Sinfo for further details.
2998 if Conversion_OK (N) then
3003 -- Otherwise full type analysis is required, as well as some semantic
3004 -- checks to make sure the argument of the conversion is appropriate.
3006 Find_Type (Subtype_Mark (N));
3007 T := Entity (Subtype_Mark (N));
3009 Check_Fully_Declared (T, N);
3010 Analyze_Expression (Expr);
3011 Validate_Remote_Type_Type_Conversion (N);
3013 -- Only remaining step is validity checks on the argument. These
3014 -- are skipped if the conversion does not come from the source.
3016 if not Comes_From_Source (N) then
3019 elsif Nkind (Expr) = N_Null then
3020 Error_Msg_N ("argument of conversion cannot be null", N);
3021 Error_Msg_N ("\use qualified expression instead", N);
3022 Set_Etype (N, Any_Type);
3024 elsif Nkind (Expr) = N_Aggregate then
3025 Error_Msg_N ("argument of conversion cannot be aggregate", N);
3026 Error_Msg_N ("\use qualified expression instead", N);
3028 elsif Nkind (Expr) = N_Allocator then
3029 Error_Msg_N ("argument of conversion cannot be an allocator", N);
3030 Error_Msg_N ("\use qualified expression instead", N);
3032 elsif Nkind (Expr) = N_String_Literal then
3033 Error_Msg_N ("argument of conversion cannot be string literal", N);
3034 Error_Msg_N ("\use qualified expression instead", N);
3036 elsif Nkind (Expr) = N_Character_Literal then
3040 Error_Msg_N ("argument of conversion cannot be character literal",
3042 Error_Msg_N ("\use qualified expression instead", N);
3045 elsif Nkind (Expr) = N_Attribute_Reference
3047 (Attribute_Name (Expr) = Name_Access or else
3048 Attribute_Name (Expr) = Name_Unchecked_Access or else
3049 Attribute_Name (Expr) = Name_Unrestricted_Access)
3051 Error_Msg_N ("argument of conversion cannot be access", N);
3052 Error_Msg_N ("\use qualified expression instead", N);
3055 end Analyze_Type_Conversion;
3057 ----------------------
3058 -- Analyze_Unary_Op --
3059 ----------------------
3061 procedure Analyze_Unary_Op (N : Node_Id) is
3062 R : constant Node_Id := Right_Opnd (N);
3063 Op_Id : Entity_Id := Entity (N);
3066 Set_Etype (N, Any_Type);
3067 Candidate_Type := Empty;
3069 Analyze_Expression (R);
3071 if Present (Op_Id) then
3072 if Ekind (Op_Id) = E_Operator then
3073 Find_Unary_Types (R, Op_Id, N);
3075 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3079 Op_Id := Get_Name_Entity_Id (Chars (N));
3081 while Present (Op_Id) loop
3083 if Ekind (Op_Id) = E_Operator then
3084 if No (Next_Entity (First_Entity (Op_Id))) then
3085 Find_Unary_Types (R, Op_Id, N);
3088 elsif Is_Overloadable (Op_Id) then
3089 Analyze_User_Defined_Unary_Op (N, Op_Id);
3092 Op_Id := Homonym (Op_Id);
3097 end Analyze_Unary_Op;
3099 ----------------------------------
3100 -- Analyze_Unchecked_Expression --
3101 ----------------------------------
3103 procedure Analyze_Unchecked_Expression (N : Node_Id) is
3105 Analyze (Expression (N), Suppress => All_Checks);
3106 Set_Etype (N, Etype (Expression (N)));
3107 Save_Interps (Expression (N), N);
3108 end Analyze_Unchecked_Expression;
3110 ---------------------------------------
3111 -- Analyze_Unchecked_Type_Conversion --
3112 ---------------------------------------
3114 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
3116 Find_Type (Subtype_Mark (N));
3117 Analyze_Expression (Expression (N));
3118 Set_Etype (N, Entity (Subtype_Mark (N)));
3119 end Analyze_Unchecked_Type_Conversion;
3121 ------------------------------------
3122 -- Analyze_User_Defined_Binary_Op --
3123 ------------------------------------
3125 procedure Analyze_User_Defined_Binary_Op
3130 -- Only do analysis if the operator Comes_From_Source, since otherwise
3131 -- the operator was generated by the expander, and all such operators
3132 -- always refer to the operators in package Standard.
3134 if Comes_From_Source (N) then
3136 F1 : constant Entity_Id := First_Formal (Op_Id);
3137 F2 : constant Entity_Id := Next_Formal (F1);
3140 -- Verify that Op_Id is a visible binary function. Note that since
3141 -- we know Op_Id is overloaded, potentially use visible means use
3142 -- visible for sure (RM 9.4(11)).
3144 if Ekind (Op_Id) = E_Function
3145 and then Present (F2)
3146 and then (Is_Immediately_Visible (Op_Id)
3147 or else Is_Potentially_Use_Visible (Op_Id))
3148 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
3149 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
3151 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3153 if Debug_Flag_E then
3154 Write_Str ("user defined operator ");
3155 Write_Name (Chars (Op_Id));
3156 Write_Str (" on node ");
3157 Write_Int (Int (N));
3163 end Analyze_User_Defined_Binary_Op;
3165 -----------------------------------
3166 -- Analyze_User_Defined_Unary_Op --
3167 -----------------------------------
3169 procedure Analyze_User_Defined_Unary_Op
3174 -- Only do analysis if the operator Comes_From_Source, since otherwise
3175 -- the operator was generated by the expander, and all such operators
3176 -- always refer to the operators in package Standard.
3178 if Comes_From_Source (N) then
3180 F : constant Entity_Id := First_Formal (Op_Id);
3183 -- Verify that Op_Id is a visible unary function. Note that since
3184 -- we know Op_Id is overloaded, potentially use visible means use
3185 -- visible for sure (RM 9.4(11)).
3187 if Ekind (Op_Id) = E_Function
3188 and then No (Next_Formal (F))
3189 and then (Is_Immediately_Visible (Op_Id)
3190 or else Is_Potentially_Use_Visible (Op_Id))
3191 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
3193 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3197 end Analyze_User_Defined_Unary_Op;
3199 ---------------------------
3200 -- Check_Arithmetic_Pair --
3201 ---------------------------
3203 procedure Check_Arithmetic_Pair
3204 (T1, T2 : Entity_Id;
3208 Op_Name : constant Name_Id := Chars (Op_Id);
3210 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
3211 -- Get specific type (i.e. non-universal type if there is one)
3213 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
3215 if T1 = Universal_Integer or else T1 = Universal_Real then
3216 return Base_Type (T2);
3218 return Base_Type (T1);
3222 -- Start of processing for Check_Arithmetic_Pair
3225 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
3227 if Is_Numeric_Type (T1)
3228 and then Is_Numeric_Type (T2)
3229 and then (Covers (T1, T2) or else Covers (T2, T1))
3231 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3234 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
3236 if Is_Fixed_Point_Type (T1)
3237 and then (Is_Fixed_Point_Type (T2)
3238 or else T2 = Universal_Real)
3240 -- If Treat_Fixed_As_Integer is set then the Etype is already set
3241 -- and no further processing is required (this is the case of an
3242 -- operator constructed by Exp_Fixd for a fixed point operation)
3243 -- Otherwise add one interpretation with universal fixed result
3244 -- If the operator is given in functional notation, it comes
3245 -- from source and Fixed_As_Integer cannot apply.
3247 if Nkind (N) not in N_Op
3248 or else not Treat_Fixed_As_Integer (N)
3250 Add_One_Interp (N, Op_Id, Universal_Fixed);
3253 elsif Is_Fixed_Point_Type (T2)
3254 and then (Nkind (N) not in N_Op
3255 or else not Treat_Fixed_As_Integer (N))
3256 and then T1 = Universal_Real
3258 Add_One_Interp (N, Op_Id, Universal_Fixed);
3260 elsif Is_Numeric_Type (T1)
3261 and then Is_Numeric_Type (T2)
3262 and then (Covers (T1, T2) or else Covers (T2, T1))
3264 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3266 elsif Is_Fixed_Point_Type (T1)
3267 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3268 or else T2 = Universal_Integer)
3270 Add_One_Interp (N, Op_Id, T1);
3272 elsif T2 = Universal_Real
3273 and then Base_Type (T1) = Base_Type (Standard_Integer)
3274 and then Op_Name = Name_Op_Multiply
3276 Add_One_Interp (N, Op_Id, Any_Fixed);
3278 elsif T1 = Universal_Real
3279 and then Base_Type (T2) = Base_Type (Standard_Integer)
3281 Add_One_Interp (N, Op_Id, Any_Fixed);
3283 elsif Is_Fixed_Point_Type (T2)
3284 and then (Base_Type (T1) = Base_Type (Standard_Integer)
3285 or else T1 = Universal_Integer)
3286 and then Op_Name = Name_Op_Multiply
3288 Add_One_Interp (N, Op_Id, T2);
3290 elsif T1 = Universal_Real and then T2 = Universal_Integer then
3291 Add_One_Interp (N, Op_Id, T1);
3293 elsif T2 = Universal_Real
3294 and then T1 = Universal_Integer
3295 and then Op_Name = Name_Op_Multiply
3297 Add_One_Interp (N, Op_Id, T2);
3300 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
3302 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
3303 -- set does not require any special processing, since the Etype is
3304 -- already set (case of operation constructed by Exp_Fixed).
3306 if Is_Integer_Type (T1)
3307 and then (Covers (T1, T2) or else Covers (T2, T1))
3309 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3312 elsif Op_Name = Name_Op_Expon then
3314 if Is_Numeric_Type (T1)
3315 and then not Is_Fixed_Point_Type (T1)
3316 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3317 or else T2 = Universal_Integer)
3319 Add_One_Interp (N, Op_Id, Base_Type (T1));
3322 else pragma Assert (Nkind (N) in N_Op_Shift);
3324 -- If not one of the predefined operators, the node may be one
3325 -- of the intrinsic functions. Its kind is always specific, and
3326 -- we can use it directly, rather than the name of the operation.
3328 if Is_Integer_Type (T1)
3329 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3330 or else T2 = Universal_Integer)
3332 Add_One_Interp (N, Op_Id, Base_Type (T1));
3335 end Check_Arithmetic_Pair;
3337 -------------------------------
3338 -- Check_Misspelled_Selector --
3339 -------------------------------
3341 procedure Check_Misspelled_Selector
3342 (Prefix : Entity_Id;
3345 Max_Suggestions : constant := 2;
3346 Nr_Of_Suggestions : Natural := 0;
3348 Suggestion_1 : Entity_Id := Empty;
3349 Suggestion_2 : Entity_Id := Empty;
3354 -- All the components of the prefix of selector Sel are matched
3355 -- against Sel and a count is maintained of possible misspellings.
3356 -- When at the end of the analysis there are one or two (not more!)
3357 -- possible misspellings, these misspellings will be suggested as
3358 -- possible correction.
3360 if not (Is_Private_Type (Prefix) or Is_Record_Type (Prefix)) then
3361 -- Concurrent types should be handled as well ???
3365 Get_Name_String (Chars (Sel));
3368 S : constant String (1 .. Name_Len) :=
3369 Name_Buffer (1 .. Name_Len);
3372 Comp := First_Entity (Prefix);
3374 while Nr_Of_Suggestions <= Max_Suggestions
3375 and then Present (Comp)
3378 if Is_Visible_Component (Comp) then
3379 Get_Name_String (Chars (Comp));
3381 if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
3382 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
3384 case Nr_Of_Suggestions is
3385 when 1 => Suggestion_1 := Comp;
3386 when 2 => Suggestion_2 := Comp;
3387 when others => exit;
3392 Comp := Next_Entity (Comp);
3395 -- Report at most two suggestions
3397 if Nr_Of_Suggestions = 1 then
3398 Error_Msg_NE ("\possible misspelling of&", Sel, Suggestion_1);
3400 elsif Nr_Of_Suggestions = 2 then
3401 Error_Msg_Node_2 := Suggestion_2;
3402 Error_Msg_NE ("\possible misspelling of& or&",
3406 end Check_Misspelled_Selector;
3408 ----------------------
3409 -- Defined_In_Scope --
3410 ----------------------
3412 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
3414 S1 : constant Entity_Id := Scope (Base_Type (T));
3418 or else (S1 = System_Aux_Id and then S = Scope (S1));
3419 end Defined_In_Scope;
3425 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
3432 Void_Interp_Seen : Boolean := False;
3435 if Extensions_Allowed then
3436 Actual := First_Actual (N);
3438 while Present (Actual) loop
3439 if not Analyzed (Etype (Actual))
3440 and then From_With_Type (Etype (Actual))
3442 Error_Msg_Qual_Level := 1;
3444 ("missing with_clause for scope of imported type&",
3445 Actual, Etype (Actual));
3446 Error_Msg_Qual_Level := 0;
3449 Next_Actual (Actual);
3453 -- Analyze each candidate call again, with full error reporting
3457 ("no candidate interpretations match the actuals:!", Nam);
3458 Err_Mode := All_Errors_Mode;
3459 All_Errors_Mode := True;
3461 -- If this is a call to an operation of a concurrent type,
3462 -- the failed interpretations have been removed from the
3463 -- name. Recover them to provide full diagnostics.
3465 if Nkind (Parent (Nam)) = N_Selected_Component then
3466 Set_Entity (Nam, Empty);
3467 New_Nam := New_Copy_Tree (Parent (Nam));
3468 Set_Is_Overloaded (New_Nam, False);
3469 Set_Is_Overloaded (Selector_Name (New_Nam), False);
3470 Set_Parent (New_Nam, Parent (Parent (Nam)));
3471 Analyze_Selected_Component (New_Nam);
3472 Get_First_Interp (Selector_Name (New_Nam), X, It);
3474 Get_First_Interp (Nam, X, It);
3477 while Present (It.Nam) loop
3478 if Etype (It.Nam) = Standard_Void_Type then
3479 Void_Interp_Seen := True;
3482 Analyze_One_Call (N, It.Nam, True, Success);
3483 Get_Next_Interp (X, It);
3486 if Nkind (N) = N_Function_Call then
3487 Get_First_Interp (Nam, X, It);
3489 while Present (It.Nam) loop
3490 if Ekind (It.Nam) = E_Function
3491 or else Ekind (It.Nam) = E_Operator
3495 Get_Next_Interp (X, It);
3499 -- If all interpretations are procedures, this deserves a
3500 -- more precise message. Ditto if this appears as the prefix
3501 -- of a selected component, which may be a lexical error.
3504 "\context requires function call, found procedure name", Nam);
3506 if Nkind (Parent (N)) = N_Selected_Component
3507 and then N = Prefix (Parent (N))
3510 "\period should probably be semicolon", Parent (N));
3513 elsif Nkind (N) = N_Procedure_Call_Statement
3514 and then not Void_Interp_Seen
3517 "\function name found in procedure call", Nam);
3520 All_Errors_Mode := Err_Mode;
3523 ---------------------------
3524 -- Find_Arithmetic_Types --
3525 ---------------------------
3527 procedure Find_Arithmetic_Types
3532 Index1, Index2 : Interp_Index;
3535 procedure Check_Right_Argument (T : Entity_Id);
3536 -- Check right operand of operator
3538 procedure Check_Right_Argument (T : Entity_Id) is
3540 if not Is_Overloaded (R) then
3541 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
3543 Get_First_Interp (R, Index2, It2);
3545 while Present (It2.Typ) loop
3546 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
3547 Get_Next_Interp (Index2, It2);
3550 end Check_Right_Argument;
3552 -- Start processing for Find_Arithmetic_Types
3555 if not Is_Overloaded (L) then
3556 Check_Right_Argument (Etype (L));
3559 Get_First_Interp (L, Index1, It1);
3561 while Present (It1.Typ) loop
3562 Check_Right_Argument (It1.Typ);
3563 Get_Next_Interp (Index1, It1);
3567 end Find_Arithmetic_Types;
3569 ------------------------
3570 -- Find_Boolean_Types --
3571 ------------------------
3573 procedure Find_Boolean_Types
3578 Index : Interp_Index;
3581 procedure Check_Numeric_Argument (T : Entity_Id);
3582 -- Special case for logical operations one of whose operands is an
3583 -- integer literal. If both are literal the result is any modular type.
3585 procedure Check_Numeric_Argument (T : Entity_Id) is
3587 if T = Universal_Integer then
3588 Add_One_Interp (N, Op_Id, Any_Modular);
3590 elsif Is_Modular_Integer_Type (T) then
3591 Add_One_Interp (N, Op_Id, T);
3593 end Check_Numeric_Argument;
3595 -- Start of processing for Find_Boolean_Types
3598 if not Is_Overloaded (L) then
3600 if Etype (L) = Universal_Integer
3601 or else Etype (L) = Any_Modular
3603 if not Is_Overloaded (R) then
3604 Check_Numeric_Argument (Etype (R));
3607 Get_First_Interp (R, Index, It);
3609 while Present (It.Typ) loop
3610 Check_Numeric_Argument (It.Typ);
3612 Get_Next_Interp (Index, It);
3616 elsif Valid_Boolean_Arg (Etype (L))
3617 and then Has_Compatible_Type (R, Etype (L))
3619 Add_One_Interp (N, Op_Id, Etype (L));
3623 Get_First_Interp (L, Index, It);
3625 while Present (It.Typ) loop
3626 if Valid_Boolean_Arg (It.Typ)
3627 and then Has_Compatible_Type (R, It.Typ)
3629 Add_One_Interp (N, Op_Id, It.Typ);
3632 Get_Next_Interp (Index, It);
3635 end Find_Boolean_Types;
3637 ---------------------------
3638 -- Find_Comparison_Types --
3639 ---------------------------
3641 procedure Find_Comparison_Types
3646 Index : Interp_Index;
3648 Found : Boolean := False;
3651 Scop : Entity_Id := Empty;
3653 procedure Try_One_Interp (T1 : Entity_Id);
3654 -- Routine to try one proposed interpretation. Note that the context
3655 -- of the operator plays no role in resolving the arguments, so that
3656 -- if there is more than one interpretation of the operands that is
3657 -- compatible with comparison, the operation is ambiguous.
3659 procedure Try_One_Interp (T1 : Entity_Id) is
3662 -- If the operator is an expanded name, then the type of the operand
3663 -- must be defined in the corresponding scope. If the type is
3664 -- universal, the context will impose the correct type.
3667 and then not Defined_In_Scope (T1, Scop)
3668 and then T1 /= Universal_Integer
3669 and then T1 /= Universal_Real
3670 and then T1 /= Any_String
3671 and then T1 /= Any_Composite
3676 if Valid_Comparison_Arg (T1)
3677 and then Has_Compatible_Type (R, T1)
3680 and then Base_Type (T1) /= Base_Type (T_F)
3682 It := Disambiguate (L, I_F, Index, Any_Type);
3684 if It = No_Interp then
3685 Ambiguous_Operands (N);
3686 Set_Etype (L, Any_Type);
3700 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
3705 -- Start processing for Find_Comparison_Types
3708 -- If left operand is aggregate, the right operand has to
3709 -- provide a usable type for it.
3711 if Nkind (L) = N_Aggregate
3712 and then Nkind (R) /= N_Aggregate
3714 Find_Comparison_Types (R, L, Op_Id, N);
3718 if Nkind (N) = N_Function_Call
3719 and then Nkind (Name (N)) = N_Expanded_Name
3721 Scop := Entity (Prefix (Name (N)));
3723 -- The prefix may be a package renaming, and the subsequent test
3724 -- requires the original package.
3726 if Ekind (Scop) = E_Package
3727 and then Present (Renamed_Entity (Scop))
3729 Scop := Renamed_Entity (Scop);
3730 Set_Entity (Prefix (Name (N)), Scop);
3734 if not Is_Overloaded (L) then
3735 Try_One_Interp (Etype (L));
3738 Get_First_Interp (L, Index, It);
3740 while Present (It.Typ) loop
3741 Try_One_Interp (It.Typ);
3742 Get_Next_Interp (Index, It);
3745 end Find_Comparison_Types;
3747 ----------------------------------------
3748 -- Find_Non_Universal_Interpretations --
3749 ----------------------------------------
3751 procedure Find_Non_Universal_Interpretations
3757 Index : Interp_Index;
3761 if T1 = Universal_Integer
3762 or else T1 = Universal_Real
3764 if not Is_Overloaded (R) then
3766 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
3768 Get_First_Interp (R, Index, It);
3770 while Present (It.Typ) loop
3771 if Covers (It.Typ, T1) then
3773 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
3776 Get_Next_Interp (Index, It);
3780 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
3782 end Find_Non_Universal_Interpretations;
3784 ------------------------------
3785 -- Find_Concatenation_Types --
3786 ------------------------------
3788 procedure Find_Concatenation_Types
3793 Op_Type : constant Entity_Id := Etype (Op_Id);
3796 if Is_Array_Type (Op_Type)
3797 and then not Is_Limited_Type (Op_Type)
3799 and then (Has_Compatible_Type (L, Op_Type)
3801 Has_Compatible_Type (L, Component_Type (Op_Type)))
3803 and then (Has_Compatible_Type (R, Op_Type)
3805 Has_Compatible_Type (R, Component_Type (Op_Type)))
3807 Add_One_Interp (N, Op_Id, Op_Type);
3809 end Find_Concatenation_Types;
3811 -------------------------
3812 -- Find_Equality_Types --
3813 -------------------------
3815 procedure Find_Equality_Types
3820 Index : Interp_Index;
3822 Found : Boolean := False;
3825 Scop : Entity_Id := Empty;
3827 procedure Try_One_Interp (T1 : Entity_Id);
3828 -- The context of the operator plays no role in resolving the
3829 -- arguments, so that if there is more than one interpretation
3830 -- of the operands that is compatible with equality, the construct
3831 -- is ambiguous and an error can be emitted now, after trying to
3832 -- disambiguate, i.e. applying preference rules.
3834 procedure Try_One_Interp (T1 : Entity_Id) is
3837 -- If the operator is an expanded name, then the type of the operand
3838 -- must be defined in the corresponding scope. If the type is
3839 -- universal, the context will impose the correct type. An anonymous
3840 -- type for a 'Access reference is also universal in this sense, as
3841 -- the actual type is obtained from context.
3844 and then not Defined_In_Scope (T1, Scop)
3845 and then T1 /= Universal_Integer
3846 and then T1 /= Universal_Real
3847 and then T1 /= Any_Access
3848 and then T1 /= Any_String
3849 and then T1 /= Any_Composite
3850 and then (Ekind (T1) /= E_Access_Subprogram_Type
3851 or else Comes_From_Source (T1))
3856 if T1 /= Standard_Void_Type
3857 and then not Is_Limited_Type (T1)
3858 and then not Is_Limited_Composite (T1)
3859 and then Ekind (T1) /= E_Anonymous_Access_Type
3860 and then Has_Compatible_Type (R, T1)
3863 and then Base_Type (T1) /= Base_Type (T_F)
3865 It := Disambiguate (L, I_F, Index, Any_Type);
3867 if It = No_Interp then
3868 Ambiguous_Operands (N);
3869 Set_Etype (L, Any_Type);
3882 if not Analyzed (L) then
3886 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
3888 if Etype (N) = Any_Type then
3890 -- Operator was not visible.
3897 -- Start of processing for Find_Equality_Types
3900 -- If left operand is aggregate, the right operand has to
3901 -- provide a usable type for it.
3903 if Nkind (L) = N_Aggregate
3904 and then Nkind (R) /= N_Aggregate
3906 Find_Equality_Types (R, L, Op_Id, N);
3910 if Nkind (N) = N_Function_Call
3911 and then Nkind (Name (N)) = N_Expanded_Name
3913 Scop := Entity (Prefix (Name (N)));
3915 -- The prefix may be a package renaming, and the subsequent test
3916 -- requires the original package.
3918 if Ekind (Scop) = E_Package
3919 and then Present (Renamed_Entity (Scop))
3921 Scop := Renamed_Entity (Scop);
3922 Set_Entity (Prefix (Name (N)), Scop);
3926 if not Is_Overloaded (L) then
3927 Try_One_Interp (Etype (L));
3930 Get_First_Interp (L, Index, It);
3932 while Present (It.Typ) loop
3933 Try_One_Interp (It.Typ);
3934 Get_Next_Interp (Index, It);
3937 end Find_Equality_Types;
3939 -------------------------
3940 -- Find_Negation_Types --
3941 -------------------------
3943 procedure Find_Negation_Types
3948 Index : Interp_Index;
3952 if not Is_Overloaded (R) then
3954 if Etype (R) = Universal_Integer then
3955 Add_One_Interp (N, Op_Id, Any_Modular);
3957 elsif Valid_Boolean_Arg (Etype (R)) then
3958 Add_One_Interp (N, Op_Id, Etype (R));
3962 Get_First_Interp (R, Index, It);
3964 while Present (It.Typ) loop
3965 if Valid_Boolean_Arg (It.Typ) then
3966 Add_One_Interp (N, Op_Id, It.Typ);
3969 Get_Next_Interp (Index, It);
3972 end Find_Negation_Types;
3974 ----------------------
3975 -- Find_Unary_Types --
3976 ----------------------
3978 procedure Find_Unary_Types
3983 Index : Interp_Index;
3987 if not Is_Overloaded (R) then
3988 if Is_Numeric_Type (Etype (R)) then
3989 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
3993 Get_First_Interp (R, Index, It);
3995 while Present (It.Typ) loop
3996 if Is_Numeric_Type (It.Typ) then
3997 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
4000 Get_Next_Interp (Index, It);
4003 end Find_Unary_Types;
4009 function Junk_Operand (N : Node_Id) return Boolean is
4013 if Error_Posted (N) then
4017 -- Get entity to be tested
4019 if Is_Entity_Name (N)
4020 and then Present (Entity (N))
4024 -- An odd case, a procedure name gets converted to a very peculiar
4025 -- function call, and here is where we detect this happening.
4027 elsif Nkind (N) = N_Function_Call
4028 and then Is_Entity_Name (Name (N))
4029 and then Present (Entity (Name (N)))
4033 -- Another odd case, there are at least some cases of selected
4034 -- components where the selected component is not marked as having
4035 -- an entity, even though the selector does have an entity
4037 elsif Nkind (N) = N_Selected_Component
4038 and then Present (Entity (Selector_Name (N)))
4040 Enode := Selector_Name (N);
4046 -- Now test the entity we got to see if it a bad case
4048 case Ekind (Entity (Enode)) is
4052 ("package name cannot be used as operand", Enode);
4054 when Generic_Unit_Kind =>
4056 ("generic unit name cannot be used as operand", Enode);
4060 ("subtype name cannot be used as operand", Enode);
4064 ("entry name cannot be used as operand", Enode);
4068 ("procedure name cannot be used as operand", Enode);
4072 ("exception name cannot be used as operand", Enode);
4074 when E_Block | E_Label | E_Loop =>
4076 ("label name cannot be used as operand", Enode);
4086 --------------------
4087 -- Operator_Check --
4088 --------------------
4090 procedure Operator_Check (N : Node_Id) is
4092 -- Test for case of no interpretation found for operator
4094 if Etype (N) = Any_Type then
4100 R := Right_Opnd (N);
4102 if Nkind (N) in N_Binary_Op then
4108 -- If either operand has no type, then don't complain further,
4109 -- since this simply means that we have a propragated error.
4112 or else Etype (R) = Any_Type
4113 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
4117 -- We explicitly check for the case of concatenation of
4118 -- component with component to avoid reporting spurious
4119 -- matching array types that might happen to be lurking
4120 -- in distant packages (such as run-time packages). This
4121 -- also prevents inconsistencies in the messages for certain
4122 -- ACVC B tests, which can vary depending on types declared
4123 -- in run-time interfaces. A further improvement, when
4124 -- aggregates are present, is to look for a well-typed operand.
4126 elsif Present (Candidate_Type)
4127 and then (Nkind (N) /= N_Op_Concat
4128 or else Is_Array_Type (Etype (L))
4129 or else Is_Array_Type (Etype (R)))
4132 if Nkind (N) = N_Op_Concat then
4133 if Etype (L) /= Any_Composite
4134 and then Is_Array_Type (Etype (L))
4136 Candidate_Type := Etype (L);
4138 elsif Etype (R) /= Any_Composite
4139 and then Is_Array_Type (Etype (R))
4141 Candidate_Type := Etype (R);
4146 ("operator for} is not directly visible!",
4147 N, First_Subtype (Candidate_Type));
4148 Error_Msg_N ("use clause would make operation legal!", N);
4151 -- If either operand is a junk operand (e.g. package name), then
4152 -- post appropriate error messages, but do not complain further.
4154 -- Note that the use of OR in this test instead of OR ELSE
4155 -- is quite deliberate, we may as well check both operands
4156 -- in the binary operator case.
4158 elsif Junk_Operand (R)
4159 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
4163 -- If we have a logical operator, one of whose operands is
4164 -- Boolean, then we know that the other operand cannot resolve
4165 -- to Boolean (since we got no interpretations), but in that
4166 -- case we pretty much know that the other operand should be
4167 -- Boolean, so resolve it that way (generating an error)
4169 elsif Nkind (N) = N_Op_And
4173 Nkind (N) = N_Op_Xor
4175 if Etype (L) = Standard_Boolean then
4176 Resolve (R, Standard_Boolean);
4178 elsif Etype (R) = Standard_Boolean then
4179 Resolve (L, Standard_Boolean);
4183 -- For an arithmetic operator or comparison operator, if one
4184 -- of the operands is numeric, then we know the other operand
4185 -- is not the same numeric type. If it is a non-numeric type,
4186 -- then probably it is intended to match the other operand.
4188 elsif Nkind (N) = N_Op_Add or else
4189 Nkind (N) = N_Op_Divide or else
4190 Nkind (N) = N_Op_Ge or else
4191 Nkind (N) = N_Op_Gt or else
4192 Nkind (N) = N_Op_Le or else
4193 Nkind (N) = N_Op_Lt or else
4194 Nkind (N) = N_Op_Mod or else
4195 Nkind (N) = N_Op_Multiply or else
4196 Nkind (N) = N_Op_Rem or else
4197 Nkind (N) = N_Op_Subtract
4199 if Is_Numeric_Type (Etype (L))
4200 and then not Is_Numeric_Type (Etype (R))
4202 Resolve (R, Etype (L));
4205 elsif Is_Numeric_Type (Etype (R))
4206 and then not Is_Numeric_Type (Etype (L))
4208 Resolve (L, Etype (R));
4212 -- Comparisons on A'Access are common enough to deserve a
4215 elsif (Nkind (N) = N_Op_Eq or else
4216 Nkind (N) = N_Op_Ne)
4217 and then Ekind (Etype (L)) = E_Access_Attribute_Type
4218 and then Ekind (Etype (R)) = E_Access_Attribute_Type
4221 ("two access attributes cannot be compared directly", N);
4223 ("\they must be converted to an explicit type for comparison",
4227 -- Another one for C programmers
4229 elsif Nkind (N) = N_Op_Concat
4230 and then Valid_Boolean_Arg (Etype (L))
4231 and then Valid_Boolean_Arg (Etype (R))
4233 Error_Msg_N ("invalid operands for concatenation", N);
4234 Error_Msg_N ("\maybe AND was meant", N);
4237 -- A special case for comparison of access parameter with null
4239 elsif Nkind (N) = N_Op_Eq
4240 and then Is_Entity_Name (L)
4241 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
4242 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
4244 and then Nkind (R) = N_Null
4246 Error_Msg_N ("access parameter is not allowed to be null", L);
4247 Error_Msg_N ("\(call would raise Constraint_Error)", L);
4251 -- If we fall through then just give general message. Note
4252 -- that in the following messages, if the operand is overloaded
4253 -- we choose an arbitrary type to complain about, but that is
4254 -- probably more useful than not giving a type at all.
4256 if Nkind (N) in N_Unary_Op then
4257 Error_Msg_Node_2 := Etype (R);
4258 Error_Msg_N ("operator& not defined for}", N);
4262 if Nkind (N) in N_Binary_Op then
4263 if not Is_Overloaded (L)
4264 and then not Is_Overloaded (R)
4265 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
4267 Error_Msg_Node_2 := Etype (R);
4268 Error_Msg_N ("there is no applicable operator& for}", N);
4271 Error_Msg_N ("invalid operand types for operator&", N);
4273 if Nkind (N) /= N_Op_Concat then
4274 Error_Msg_NE ("\left operand has}!", N, Etype (L));
4275 Error_Msg_NE ("\right operand has}!", N, Etype (R));
4284 -----------------------
4285 -- Try_Indirect_Call --
4286 -----------------------
4288 function Try_Indirect_Call
4294 Actuals : constant List_Id := Parameter_Associations (N);
4299 Actual := First (Actuals);
4300 Formal := First_Formal (Designated_Type (Typ));
4301 while Present (Actual)
4302 and then Present (Formal)
4304 if not Has_Compatible_Type (Actual, Etype (Formal)) then
4309 Next_Formal (Formal);
4312 if No (Actual) and then No (Formal) then
4313 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
4315 -- Nam is a candidate interpretation for the name in the call,
4316 -- if it is not an indirect call.
4318 if not Is_Type (Nam)
4319 and then Is_Entity_Name (Name (N))
4321 Set_Entity (Name (N), Nam);
4328 end Try_Indirect_Call;
4330 ----------------------
4331 -- Try_Indexed_Call --
4332 ----------------------
4334 function Try_Indexed_Call
4340 Actuals : constant List_Id := Parameter_Associations (N);
4345 Actual := First (Actuals);
4346 Index := First_Index (Typ);
4347 while Present (Actual)
4348 and then Present (Index)
4350 -- If the parameter list has a named association, the expression
4351 -- is definitely a call and not an indexed component.
4353 if Nkind (Actual) = N_Parameter_Association then
4357 if not Has_Compatible_Type (Actual, Etype (Index)) then
4365 if No (Actual) and then No (Index) then
4366 Add_One_Interp (N, Nam, Component_Type (Typ));
4368 -- Nam is a candidate interpretation for the name in the call,
4369 -- if it is not an indirect call.
4371 if not Is_Type (Nam)
4372 and then Is_Entity_Name (Name (N))
4374 Set_Entity (Name (N), Nam);
4382 end Try_Indexed_Call;