1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004, 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 Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Errout; use Errout;
33 with Exp_Util; use Exp_Util;
34 with Fname; use Fname;
35 with Itypes; use Itypes;
37 with Lib.Xref; use Lib.Xref;
38 with Namet; use Namet;
39 with Nlists; use Nlists;
40 with Nmake; use Nmake;
42 with Output; use Output;
43 with Restrict; use Restrict;
44 with Rident; use Rident;
46 with Sem_Cat; use Sem_Cat;
47 with Sem_Ch3; use Sem_Ch3;
48 with Sem_Ch8; use Sem_Ch8;
49 with Sem_Dist; use Sem_Dist;
50 with Sem_Eval; use Sem_Eval;
51 with Sem_Res; use Sem_Res;
52 with Sem_Util; use Sem_Util;
53 with Sem_Type; use Sem_Type;
54 with Stand; use Stand;
55 with Sinfo; use Sinfo;
56 with Snames; use Snames;
57 with Tbuild; use Tbuild;
59 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
61 package body Sem_Ch4 is
63 -----------------------
64 -- Local Subprograms --
65 -----------------------
67 procedure Analyze_Expression (N : Node_Id);
68 -- For expressions that are not names, this is just a call to analyze.
69 -- If the expression is a name, it may be a call to a parameterless
70 -- function, and if so must be converted into an explicit call node
71 -- and analyzed as such. This deproceduring must be done during the first
72 -- pass of overload resolution, because otherwise a procedure call with
73 -- overloaded actuals may fail to resolve. See 4327-001 for an example.
75 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id);
76 -- Analyze a call of the form "+"(x, y), etc. The prefix of the call
77 -- is an operator name or an expanded name whose selector is an operator
78 -- name, and one possible interpretation is as a predefined operator.
80 procedure Analyze_Overloaded_Selected_Component (N : Node_Id);
81 -- If the prefix of a selected_component is overloaded, the proper
82 -- interpretation that yields a record type with the proper selector
83 -- name must be selected.
85 procedure Analyze_User_Defined_Binary_Op (N : Node_Id; Op_Id : Entity_Id);
86 -- Procedure to analyze a user defined binary operator, which is resolved
87 -- like a function, but instead of a list of actuals it is presented
88 -- with the left and right operands of an operator node.
90 procedure Analyze_User_Defined_Unary_Op (N : Node_Id; Op_Id : Entity_Id);
91 -- Procedure to analyze a user defined unary operator, which is resolved
92 -- like a function, but instead of a list of actuals, it is presented with
93 -- the operand of the operator node.
95 procedure Ambiguous_Operands (N : Node_Id);
96 -- for equality, membership, and comparison operators with overloaded
97 -- arguments, list possible interpretations.
99 procedure Analyze_One_Call
103 Success : out Boolean);
104 -- Check one interpretation of an overloaded subprogram name for
105 -- compatibility with the types of the actuals in a call. If there is a
106 -- single interpretation which does not match, post error if Report is
109 -- Nam is the entity that provides the formals against which the actuals
110 -- are checked. Nam is either the name of a subprogram, or the internal
111 -- subprogram type constructed for an access_to_subprogram. If the actuals
112 -- are compatible with Nam, then Nam is added to the list of candidate
113 -- interpretations for N, and Success is set to True.
115 procedure Check_Misspelled_Selector
118 -- Give possible misspelling diagnostic if Sel is likely to be
119 -- a misspelling of one of the selectors of the Prefix.
120 -- This is called by Analyze_Selected_Component after producing
121 -- an invalid selector error message.
123 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean;
124 -- Verify that type T is declared in scope S. Used to find intepretations
125 -- for operators given by expanded names. This is abstracted as a separate
126 -- function to handle extensions to System, where S is System, but T is
127 -- declared in the extension.
129 procedure Find_Arithmetic_Types
133 -- L and R are the operands of an arithmetic operator. Find
134 -- consistent pairs of interpretations for L and R that have a
135 -- numeric type consistent with the semantics of the operator.
137 procedure Find_Comparison_Types
141 -- L and R are operands of a comparison operator. Find consistent
142 -- pairs of interpretations for L and R.
144 procedure Find_Concatenation_Types
148 -- For the four varieties of concatenation
150 procedure Find_Equality_Types
154 -- Ditto for equality operators
156 procedure Find_Boolean_Types
160 -- Ditto for binary logical operations
162 procedure Find_Negation_Types
166 -- Find consistent interpretation for operand of negation operator
168 procedure Find_Non_Universal_Interpretations
173 -- For equality and comparison operators, the result is always boolean,
174 -- and the legality of the operation is determined from the visibility
175 -- of the operand types. If one of the operands has a universal interpre-
176 -- tation, the legality check uses some compatible non-universal
177 -- interpretation of the other operand. N can be an operator node, or
178 -- a function call whose name is an operator designator.
180 procedure Find_Unary_Types
184 -- Unary arithmetic types: plus, minus, abs
186 procedure Check_Arithmetic_Pair
190 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid
191 -- types for left and right operand. Determine whether they constitute
192 -- a valid pair for the given operator, and record the corresponding
193 -- interpretation of the operator node. The node N may be an operator
194 -- node (the usual case) or a function call whose prefix is an operator
195 -- designator. In both cases Op_Id is the operator name itself.
197 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id);
198 -- Give detailed information on overloaded call where none of the
199 -- interpretations match. N is the call node, Nam the designator for
200 -- the overloaded entity being called.
202 function Junk_Operand (N : Node_Id) return Boolean;
203 -- Test for an operand that is an inappropriate entity (e.g. a package
204 -- name or a label). If so, issue an error message and return True. If
205 -- the operand is not an inappropriate entity kind, return False.
207 procedure Operator_Check (N : Node_Id);
208 -- Verify that an operator has received some valid interpretation. If none
209 -- was found, determine whether a use clause would make the operation
210 -- legal. The variable Candidate_Type (defined in Sem_Type) is set for
211 -- every type compatible with the operator, even if the operator for the
212 -- type is not directly visible. The routine uses this type to emit a more
213 -- informative message.
215 procedure Process_Implicit_Dereference_Prefix
218 -- Called when P is the prefix of an implicit dereference, denoting an
219 -- object E. If in semantics only mode (-gnatc), record that is a
220 -- reference to E. Normally, such a reference is generated only when the
221 -- implicit dereference is expanded into an explicit one. E may be empty,
222 -- in which case this procedure does nothing.
224 procedure Remove_Abstract_Operations (N : Node_Id);
225 -- Ada 2005: implementation of AI-310. An abstract non-dispatching
226 -- operation is not a candidate interpretation.
228 function Try_Indexed_Call
231 Typ : Entity_Id) return Boolean;
232 -- If a function has defaults for all its actuals, a call to it may
233 -- in fact be an indexing on the result of the call. Try_Indexed_Call
234 -- attempts the interpretation as an indexing, prior to analysis as
235 -- a call. If both are possible, the node is overloaded with both
236 -- interpretations (same symbol but two different types).
238 function Try_Indirect_Call
241 Typ : Entity_Id) return Boolean;
242 -- Similarly, a function F that needs no actuals can return an access
243 -- to a subprogram, and the call F (X) interpreted as F.all (X). In
244 -- this case the call may be overloaded with both interpretations.
246 function Try_Object_Operation (N : Node_Id) return Boolean;
247 -- Ada 2005 (AI-252): Give support to the object operation notation
249 ------------------------
250 -- Ambiguous_Operands --
251 ------------------------
253 procedure Ambiguous_Operands (N : Node_Id) is
254 procedure List_Operand_Interps (Opnd : Node_Id);
256 --------------------------
257 -- List_Operand_Interps --
258 --------------------------
260 procedure List_Operand_Interps (Opnd : Node_Id) is
265 if Is_Overloaded (Opnd) then
266 if Nkind (Opnd) in N_Op then
268 elsif Nkind (Opnd) = N_Function_Call then
278 if Opnd = Left_Opnd (N) then
280 ("\left operand has the following interpretations", N);
283 ("\right operand has the following interpretations", N);
287 List_Interps (Nam, Err);
288 end List_Operand_Interps;
290 -- Start of processing for Ambiguous_Operands
294 or else Nkind (N) = N_Not_In
296 Error_Msg_N ("ambiguous operands for membership", N);
298 elsif Nkind (N) = N_Op_Eq
299 or else Nkind (N) = N_Op_Ne
301 Error_Msg_N ("ambiguous operands for equality", N);
304 Error_Msg_N ("ambiguous operands for comparison", N);
307 if All_Errors_Mode then
308 List_Operand_Interps (Left_Opnd (N));
309 List_Operand_Interps (Right_Opnd (N));
311 Error_Msg_N ("\use -gnatf switch for details", N);
313 end Ambiguous_Operands;
315 -----------------------
316 -- Analyze_Aggregate --
317 -----------------------
319 -- Most of the analysis of Aggregates requires that the type be known,
320 -- and is therefore put off until resolution.
322 procedure Analyze_Aggregate (N : Node_Id) is
324 if No (Etype (N)) then
325 Set_Etype (N, Any_Composite);
327 end Analyze_Aggregate;
329 -----------------------
330 -- Analyze_Allocator --
331 -----------------------
333 procedure Analyze_Allocator (N : Node_Id) is
334 Loc : constant Source_Ptr := Sloc (N);
335 Sav_Errs : constant Nat := Serious_Errors_Detected;
336 E : Node_Id := Expression (N);
337 Acc_Type : Entity_Id;
341 Check_Restriction (No_Allocators, N);
343 if Nkind (E) = N_Qualified_Expression then
344 Acc_Type := Create_Itype (E_Allocator_Type, N);
345 Set_Etype (Acc_Type, Acc_Type);
346 Init_Size_Align (Acc_Type);
347 Find_Type (Subtype_Mark (E));
348 Type_Id := Entity (Subtype_Mark (E));
349 Check_Fully_Declared (Type_Id, N);
350 Set_Directly_Designated_Type (Acc_Type, Type_Id);
352 if Is_Limited_Type (Type_Id)
353 and then Comes_From_Source (N)
354 and then not In_Instance_Body
356 -- Ada 2005 (AI-287): Do not post an error if the expression
357 -- corresponds to a limited aggregate. Limited aggregates
358 -- are checked in sem_aggr in a per-component manner
359 -- (compare with handling of Get_Value subprogram).
361 if Ada_Version >= Ada_05
362 and then Nkind (Expression (E)) = N_Aggregate
366 Error_Msg_N ("initialization not allowed for limited types", N);
367 Explain_Limited_Type (Type_Id, N);
371 Analyze_And_Resolve (Expression (E), Type_Id);
373 -- A qualified expression requires an exact match of the type,
374 -- class-wide matching is not allowed.
376 if Is_Class_Wide_Type (Type_Id)
377 and then Base_Type (Etype (Expression (E))) /= Base_Type (Type_Id)
379 Wrong_Type (Expression (E), Type_Id);
382 Check_Non_Static_Context (Expression (E));
384 -- We don't analyze the qualified expression itself because it's
385 -- part of the allocator
387 Set_Etype (E, Type_Id);
389 -- Case where no qualified expression is present
396 -- If the allocator includes a N_Subtype_Indication then a
397 -- constraint is present, otherwise the node is a subtype mark.
398 -- Introduce an explicit subtype declaration into the tree
399 -- defining some anonymous subtype and rewrite the allocator to
400 -- use this subtype rather than the subtype indication.
402 -- It is important to introduce the explicit subtype declaration
403 -- so that the bounds of the subtype indication are attached to
404 -- the tree in case the allocator is inside a generic unit.
406 if Nkind (E) = N_Subtype_Indication then
408 -- A constraint is only allowed for a composite type in Ada
409 -- 95. In Ada 83, a constraint is also allowed for an
410 -- access-to-composite type, but the constraint is ignored.
412 Find_Type (Subtype_Mark (E));
414 if Is_Elementary_Type (Entity (Subtype_Mark (E))) then
415 if not (Ada_Version = Ada_83
416 and then Is_Access_Type (Entity (Subtype_Mark (E))))
418 Error_Msg_N ("constraint not allowed here", E);
420 if Nkind (Constraint (E))
421 = N_Index_Or_Discriminant_Constraint
424 ("\if qualified expression was meant, " &
425 "use apostrophe", Constraint (E));
429 -- Get rid of the bogus constraint:
431 Rewrite (E, New_Copy_Tree (Subtype_Mark (E)));
432 Analyze_Allocator (N);
436 if Expander_Active then
438 Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
441 Make_Subtype_Declaration (Loc,
442 Defining_Identifier => Def_Id,
443 Subtype_Indication => Relocate_Node (E)));
445 if Sav_Errs /= Serious_Errors_Detected
446 and then Nkind (Constraint (E))
447 = N_Index_Or_Discriminant_Constraint
450 ("if qualified expression was meant, " &
451 "use apostrophe!", Constraint (E));
454 E := New_Occurrence_Of (Def_Id, Loc);
455 Rewrite (Expression (N), E);
459 Type_Id := Process_Subtype (E, N);
460 Acc_Type := Create_Itype (E_Allocator_Type, N);
461 Set_Etype (Acc_Type, Acc_Type);
462 Init_Size_Align (Acc_Type);
463 Set_Directly_Designated_Type (Acc_Type, Type_Id);
464 Check_Fully_Declared (Type_Id, N);
468 if Can_Never_Be_Null (Type_Id) then
469 Error_Msg_N ("(Ada 2005) qualified expression required",
473 -- Check restriction against dynamically allocated protected
474 -- objects. Note that when limited aggregates are supported,
475 -- a similar test should be applied to an allocator with a
476 -- qualified expression ???
478 if Is_Protected_Type (Type_Id) then
479 Check_Restriction (No_Protected_Type_Allocators, N);
482 -- Check for missing initialization. Skip this check if we already
483 -- had errors on analyzing the allocator, since in that case these
484 -- are probably cascaded errors
486 if Is_Indefinite_Subtype (Type_Id)
487 and then Serious_Errors_Detected = Sav_Errs
489 if Is_Class_Wide_Type (Type_Id) then
491 ("initialization required in class-wide allocation", N);
494 ("initialization required in unconstrained allocation", N);
500 if Is_Abstract (Type_Id) then
501 Error_Msg_N ("cannot allocate abstract object", E);
504 if Has_Task (Designated_Type (Acc_Type)) then
505 Check_Restriction (No_Tasking, N);
506 Check_Restriction (Max_Tasks, N);
507 Check_Restriction (No_Task_Allocators, N);
510 -- If the No_Streams restriction is set, check that the type of the
511 -- object is not, and does not contain, any subtype derived from
512 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
513 -- Has_Stream just for efficiency reasons. There is no point in
514 -- spending time on a Has_Stream check if the restriction is not set.
516 if Restrictions.Set (No_Streams) then
517 if Has_Stream (Designated_Type (Acc_Type)) then
518 Check_Restriction (No_Streams, N);
522 Set_Etype (N, Acc_Type);
524 if not Is_Library_Level_Entity (Acc_Type) then
525 Check_Restriction (No_Local_Allocators, N);
528 -- Ada 2005 (AI-231): Static checks
530 if Ada_Version >= Ada_05
531 and then (Null_Exclusion_Present (N)
532 or else Can_Never_Be_Null (Etype (N)))
534 Null_Exclusion_Static_Checks (N);
537 if Serious_Errors_Detected > Sav_Errs then
538 Set_Error_Posted (N);
539 Set_Etype (N, Any_Type);
541 end Analyze_Allocator;
543 ---------------------------
544 -- Analyze_Arithmetic_Op --
545 ---------------------------
547 procedure Analyze_Arithmetic_Op (N : Node_Id) is
548 L : constant Node_Id := Left_Opnd (N);
549 R : constant Node_Id := Right_Opnd (N);
553 Candidate_Type := Empty;
554 Analyze_Expression (L);
555 Analyze_Expression (R);
557 -- If the entity is already set, the node is the instantiation of
558 -- a generic node with a non-local reference, or was manufactured
559 -- by a call to Make_Op_xxx. In either case the entity is known to
560 -- be valid, and we do not need to collect interpretations, instead
561 -- we just get the single possible interpretation.
565 if Present (Op_Id) then
566 if Ekind (Op_Id) = E_Operator then
568 if (Nkind (N) = N_Op_Divide or else
569 Nkind (N) = N_Op_Mod or else
570 Nkind (N) = N_Op_Multiply or else
571 Nkind (N) = N_Op_Rem)
572 and then Treat_Fixed_As_Integer (N)
576 Set_Etype (N, Any_Type);
577 Find_Arithmetic_Types (L, R, Op_Id, N);
581 Set_Etype (N, Any_Type);
582 Add_One_Interp (N, Op_Id, Etype (Op_Id));
585 -- Entity is not already set, so we do need to collect interpretations
588 Op_Id := Get_Name_Entity_Id (Chars (N));
589 Set_Etype (N, Any_Type);
591 while Present (Op_Id) loop
592 if Ekind (Op_Id) = E_Operator
593 and then Present (Next_Entity (First_Entity (Op_Id)))
595 Find_Arithmetic_Types (L, R, Op_Id, N);
597 -- The following may seem superfluous, because an operator cannot
598 -- be generic, but this ignores the cleverness of the author of
601 elsif Is_Overloadable (Op_Id) then
602 Analyze_User_Defined_Binary_Op (N, Op_Id);
605 Op_Id := Homonym (Op_Id);
610 end Analyze_Arithmetic_Op;
616 -- Function, procedure, and entry calls are checked here. The Name in
617 -- the call may be overloaded. The actuals have been analyzed and may
618 -- themselves be overloaded. On exit from this procedure, the node N
619 -- may have zero, one or more interpretations. In the first case an
620 -- error message is produced. In the last case, the node is flagged
621 -- as overloaded and the interpretations are collected in All_Interp.
623 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
624 -- the type-checking is similar to that of other calls.
626 procedure Analyze_Call (N : Node_Id) is
627 Actuals : constant List_Id := Parameter_Associations (N);
628 Nam : Node_Id := Name (N);
632 Success : Boolean := False;
634 function Name_Denotes_Function return Boolean;
635 -- If the type of the name is an access to subprogram, this may be
636 -- the type of a name, or the return type of the function being called.
637 -- If the name is not an entity then it can denote a protected function.
638 -- Until we distinguish Etype from Return_Type, we must use this
639 -- routine to resolve the meaning of the name in the call.
641 ---------------------------
642 -- Name_Denotes_Function --
643 ---------------------------
645 function Name_Denotes_Function return Boolean is
647 if Is_Entity_Name (Nam) then
648 return Ekind (Entity (Nam)) = E_Function;
650 elsif Nkind (Nam) = N_Selected_Component then
651 return Ekind (Entity (Selector_Name (Nam))) = E_Function;
656 end Name_Denotes_Function;
658 -- Start of processing for Analyze_Call
661 -- Initialize the type of the result of the call to the error type,
662 -- which will be reset if the type is successfully resolved.
664 Set_Etype (N, Any_Type);
666 if not Is_Overloaded (Nam) then
668 -- Only one interpretation to check
670 if Ekind (Etype (Nam)) = E_Subprogram_Type then
671 Nam_Ent := Etype (Nam);
673 elsif Is_Access_Type (Etype (Nam))
674 and then Ekind (Designated_Type (Etype (Nam))) = E_Subprogram_Type
675 and then not Name_Denotes_Function
677 Nam_Ent := Designated_Type (Etype (Nam));
678 Insert_Explicit_Dereference (Nam);
680 -- Selected component case. Simple entry or protected operation,
681 -- where the entry name is given by the selector name.
683 elsif Nkind (Nam) = N_Selected_Component then
684 Nam_Ent := Entity (Selector_Name (Nam));
686 if Ekind (Nam_Ent) /= E_Entry
687 and then Ekind (Nam_Ent) /= E_Entry_Family
688 and then Ekind (Nam_Ent) /= E_Function
689 and then Ekind (Nam_Ent) /= E_Procedure
691 Error_Msg_N ("name in call is not a callable entity", Nam);
692 Set_Etype (N, Any_Type);
696 -- If the name is an Indexed component, it can be a call to a member
697 -- of an entry family. The prefix must be a selected component whose
698 -- selector is the entry. Analyze_Procedure_Call normalizes several
699 -- kinds of call into this form.
701 elsif Nkind (Nam) = N_Indexed_Component then
703 if Nkind (Prefix (Nam)) = N_Selected_Component then
704 Nam_Ent := Entity (Selector_Name (Prefix (Nam)));
706 Error_Msg_N ("name in call is not a callable entity", Nam);
707 Set_Etype (N, Any_Type);
711 elsif not Is_Entity_Name (Nam) then
712 Error_Msg_N ("name in call is not a callable entity", Nam);
713 Set_Etype (N, Any_Type);
717 Nam_Ent := Entity (Nam);
719 -- If no interpretations, give error message
721 if not Is_Overloadable (Nam_Ent) then
723 L : constant Boolean := Is_List_Member (N);
724 K : constant Node_Kind := Nkind (Parent (N));
727 -- If the node is in a list whose parent is not an
728 -- expression then it must be an attempted procedure call.
730 if L and then K not in N_Subexpr then
731 if Ekind (Entity (Nam)) = E_Generic_Procedure then
733 ("must instantiate generic procedure& before call",
737 ("procedure or entry name expected", Nam);
740 -- Check for tasking cases where only an entry call will do
743 and then (K = N_Entry_Call_Alternative
744 or else K = N_Triggering_Alternative)
746 Error_Msg_N ("entry name expected", Nam);
748 -- Otherwise give general error message
751 Error_Msg_N ("invalid prefix in call", Nam);
759 Analyze_One_Call (N, Nam_Ent, True, Success);
762 -- An overloaded selected component must denote overloaded
763 -- operations of a concurrent type. The interpretations are
764 -- attached to the simple name of those operations.
766 if Nkind (Nam) = N_Selected_Component then
767 Nam := Selector_Name (Nam);
770 Get_First_Interp (Nam, X, It);
772 while Present (It.Nam) loop
775 -- Name may be call that returns an access to subprogram, or more
776 -- generally an overloaded expression one of whose interpretations
777 -- yields an access to subprogram. If the name is an entity, we
778 -- do not dereference, because the node is a call that returns
779 -- the access type: note difference between f(x), where the call
780 -- may return an access subprogram type, and f(x)(y), where the
781 -- type returned by the call to f is implicitly dereferenced to
782 -- analyze the outer call.
784 if Is_Access_Type (Nam_Ent) then
785 Nam_Ent := Designated_Type (Nam_Ent);
787 elsif Is_Access_Type (Etype (Nam_Ent))
788 and then not Is_Entity_Name (Nam)
789 and then Ekind (Designated_Type (Etype (Nam_Ent)))
792 Nam_Ent := Designated_Type (Etype (Nam_Ent));
795 Analyze_One_Call (N, Nam_Ent, False, Success);
797 -- If the interpretation succeeds, mark the proper type of the
798 -- prefix (any valid candidate will do). If not, remove the
799 -- candidate interpretation. This only needs to be done for
800 -- overloaded protected operations, for other entities disambi-
801 -- guation is done directly in Resolve.
804 Set_Etype (Nam, It.Typ);
806 elsif Nkind (Name (N)) = N_Selected_Component
807 or else Nkind (Name (N)) = N_Function_Call
812 Get_Next_Interp (X, It);
815 -- If the name is the result of a function call, it can only
816 -- be a call to a function returning an access to subprogram.
817 -- Insert explicit dereference.
819 if Nkind (Nam) = N_Function_Call then
820 Insert_Explicit_Dereference (Nam);
823 if Etype (N) = Any_Type then
825 -- None of the interpretations is compatible with the actuals
827 Diagnose_Call (N, Nam);
829 -- Special checks for uninstantiated put routines
831 if Nkind (N) = N_Procedure_Call_Statement
832 and then Is_Entity_Name (Nam)
833 and then Chars (Nam) = Name_Put
834 and then List_Length (Actuals) = 1
837 Arg : constant Node_Id := First (Actuals);
841 if Nkind (Arg) = N_Parameter_Association then
842 Typ := Etype (Explicit_Actual_Parameter (Arg));
847 if Is_Signed_Integer_Type (Typ) then
849 ("possible missing instantiation of " &
850 "'Text_'I'O.'Integer_'I'O!", Nam);
852 elsif Is_Modular_Integer_Type (Typ) then
854 ("possible missing instantiation of " &
855 "'Text_'I'O.'Modular_'I'O!", Nam);
857 elsif Is_Floating_Point_Type (Typ) then
859 ("possible missing instantiation of " &
860 "'Text_'I'O.'Float_'I'O!", Nam);
862 elsif Is_Ordinary_Fixed_Point_Type (Typ) then
864 ("possible missing instantiation of " &
865 "'Text_'I'O.'Fixed_'I'O!", Nam);
867 elsif Is_Decimal_Fixed_Point_Type (Typ) then
869 ("possible missing instantiation of " &
870 "'Text_'I'O.'Decimal_'I'O!", Nam);
872 elsif Is_Enumeration_Type (Typ) then
874 ("possible missing instantiation of " &
875 "'Text_'I'O.'Enumeration_'I'O!", Nam);
880 elsif not Is_Overloaded (N)
881 and then Is_Entity_Name (Nam)
883 -- Resolution yields a single interpretation. Verify that
884 -- is has the proper capitalization.
886 Set_Entity_With_Style_Check (Nam, Entity (Nam));
887 Generate_Reference (Entity (Nam), Nam);
889 Set_Etype (Nam, Etype (Entity (Nam)));
891 Remove_Abstract_Operations (N);
898 ---------------------------
899 -- Analyze_Comparison_Op --
900 ---------------------------
902 procedure Analyze_Comparison_Op (N : Node_Id) is
903 L : constant Node_Id := Left_Opnd (N);
904 R : constant Node_Id := Right_Opnd (N);
905 Op_Id : Entity_Id := Entity (N);
908 Set_Etype (N, Any_Type);
909 Candidate_Type := Empty;
911 Analyze_Expression (L);
912 Analyze_Expression (R);
914 if Present (Op_Id) then
915 if Ekind (Op_Id) = E_Operator then
916 Find_Comparison_Types (L, R, Op_Id, N);
918 Add_One_Interp (N, Op_Id, Etype (Op_Id));
921 if Is_Overloaded (L) then
922 Set_Etype (L, Intersect_Types (L, R));
926 Op_Id := Get_Name_Entity_Id (Chars (N));
927 while Present (Op_Id) loop
928 if Ekind (Op_Id) = E_Operator then
929 Find_Comparison_Types (L, R, Op_Id, N);
931 Analyze_User_Defined_Binary_Op (N, Op_Id);
934 Op_Id := Homonym (Op_Id);
939 end Analyze_Comparison_Op;
941 ---------------------------
942 -- Analyze_Concatenation --
943 ---------------------------
945 -- If the only one-dimensional array type in scope is String,
946 -- this is the resulting type of the operation. Otherwise there
947 -- will be a concatenation operation defined for each user-defined
948 -- one-dimensional array.
950 procedure Analyze_Concatenation (N : Node_Id) is
951 L : constant Node_Id := Left_Opnd (N);
952 R : constant Node_Id := Right_Opnd (N);
953 Op_Id : Entity_Id := Entity (N);
958 Set_Etype (N, Any_Type);
959 Candidate_Type := Empty;
961 Analyze_Expression (L);
962 Analyze_Expression (R);
964 -- If the entity is present, the node appears in an instance,
965 -- and denotes a predefined concatenation operation. The resulting
966 -- type is obtained from the arguments when possible. If the arguments
967 -- are aggregates, the array type and the concatenation type must be
970 if Present (Op_Id) then
971 if Ekind (Op_Id) = E_Operator then
973 LT := Base_Type (Etype (L));
974 RT := Base_Type (Etype (R));
976 if Is_Array_Type (LT)
977 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
979 Add_One_Interp (N, Op_Id, LT);
981 elsif Is_Array_Type (RT)
982 and then LT = Base_Type (Component_Type (RT))
984 Add_One_Interp (N, Op_Id, RT);
986 -- If one operand is a string type or a user-defined array type,
987 -- and the other is a literal, result is of the specific type.
990 (Root_Type (LT) = Standard_String
991 or else Scope (LT) /= Standard_Standard)
992 and then Etype (R) = Any_String
994 Add_One_Interp (N, Op_Id, LT);
997 (Root_Type (RT) = Standard_String
998 or else Scope (RT) /= Standard_Standard)
999 and then Etype (L) = Any_String
1001 Add_One_Interp (N, Op_Id, RT);
1003 elsif not Is_Generic_Type (Etype (Op_Id)) then
1004 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1007 -- Type and its operations must be visible
1009 Set_Entity (N, Empty);
1010 Analyze_Concatenation (N);
1014 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1018 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
1019 while Present (Op_Id) loop
1020 if Ekind (Op_Id) = E_Operator then
1021 Find_Concatenation_Types (L, R, Op_Id, N);
1023 Analyze_User_Defined_Binary_Op (N, Op_Id);
1026 Op_Id := Homonym (Op_Id);
1031 end Analyze_Concatenation;
1033 ------------------------------------
1034 -- Analyze_Conditional_Expression --
1035 ------------------------------------
1037 procedure Analyze_Conditional_Expression (N : Node_Id) is
1038 Condition : constant Node_Id := First (Expressions (N));
1039 Then_Expr : constant Node_Id := Next (Condition);
1040 Else_Expr : constant Node_Id := Next (Then_Expr);
1042 Analyze_Expression (Condition);
1043 Analyze_Expression (Then_Expr);
1044 Analyze_Expression (Else_Expr);
1045 Set_Etype (N, Etype (Then_Expr));
1046 end Analyze_Conditional_Expression;
1048 -------------------------
1049 -- Analyze_Equality_Op --
1050 -------------------------
1052 procedure Analyze_Equality_Op (N : Node_Id) is
1053 Loc : constant Source_Ptr := Sloc (N);
1054 L : constant Node_Id := Left_Opnd (N);
1055 R : constant Node_Id := Right_Opnd (N);
1059 Set_Etype (N, Any_Type);
1060 Candidate_Type := Empty;
1062 Analyze_Expression (L);
1063 Analyze_Expression (R);
1065 -- If the entity is set, the node is a generic instance with a non-local
1066 -- reference to the predefined operator or to a user-defined function.
1067 -- It can also be an inequality that is expanded into the negation of a
1068 -- call to a user-defined equality operator.
1070 -- For the predefined case, the result is Boolean, regardless of the
1071 -- type of the operands. The operands may even be limited, if they are
1072 -- generic actuals. If they are overloaded, label the left argument with
1073 -- the common type that must be present, or with the type of the formal
1074 -- of the user-defined function.
1076 if Present (Entity (N)) then
1077 Op_Id := Entity (N);
1079 if Ekind (Op_Id) = E_Operator then
1080 Add_One_Interp (N, Op_Id, Standard_Boolean);
1082 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1085 if Is_Overloaded (L) then
1086 if Ekind (Op_Id) = E_Operator then
1087 Set_Etype (L, Intersect_Types (L, R));
1089 Set_Etype (L, Etype (First_Formal (Op_Id)));
1094 Op_Id := Get_Name_Entity_Id (Chars (N));
1095 while Present (Op_Id) loop
1096 if Ekind (Op_Id) = E_Operator then
1097 Find_Equality_Types (L, R, Op_Id, N);
1099 Analyze_User_Defined_Binary_Op (N, Op_Id);
1102 Op_Id := Homonym (Op_Id);
1106 -- If there was no match, and the operator is inequality, this may
1107 -- be a case where inequality has not been made explicit, as for
1108 -- tagged types. Analyze the node as the negation of an equality
1109 -- operation. This cannot be done earlier, because before analysis
1110 -- we cannot rule out the presence of an explicit inequality.
1112 if Etype (N) = Any_Type
1113 and then Nkind (N) = N_Op_Ne
1115 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1117 while Present (Op_Id) loop
1119 if Ekind (Op_Id) = E_Operator then
1120 Find_Equality_Types (L, R, Op_Id, N);
1122 Analyze_User_Defined_Binary_Op (N, Op_Id);
1125 Op_Id := Homonym (Op_Id);
1128 if Etype (N) /= Any_Type then
1129 Op_Id := Entity (N);
1135 Left_Opnd => Relocate_Node (Left_Opnd (N)),
1136 Right_Opnd => Relocate_Node (Right_Opnd (N)))));
1138 Set_Entity (Right_Opnd (N), Op_Id);
1144 end Analyze_Equality_Op;
1146 ----------------------------------
1147 -- Analyze_Explicit_Dereference --
1148 ----------------------------------
1150 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1151 Loc : constant Source_Ptr := Sloc (N);
1152 P : constant Node_Id := Prefix (N);
1158 function Is_Function_Type return Boolean;
1159 -- Check whether node may be interpreted as an implicit function call
1161 ----------------------
1162 -- Is_Function_Type --
1163 ----------------------
1165 function Is_Function_Type return Boolean is
1170 if not Is_Overloaded (N) then
1171 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1172 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1175 Get_First_Interp (N, I, It);
1177 while Present (It.Nam) loop
1178 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1179 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1184 Get_Next_Interp (I, It);
1189 end Is_Function_Type;
1191 -- Start of processing for Analyze_Explicit_Deference
1195 Set_Etype (N, Any_Type);
1197 -- Test for remote access to subprogram type, and if so return
1198 -- after rewriting the original tree.
1200 if Remote_AST_E_Dereference (P) then
1204 -- Normal processing for other than remote access to subprogram type
1206 if not Is_Overloaded (P) then
1207 if Is_Access_Type (Etype (P)) then
1209 -- Set the Etype. We need to go thru Is_For_Access_Subtypes
1210 -- to avoid other problems caused by the Private_Subtype
1211 -- and it is safe to go to the Base_Type because this is the
1212 -- same as converting the access value to its Base_Type.
1215 DT : Entity_Id := Designated_Type (Etype (P));
1218 if Ekind (DT) = E_Private_Subtype
1219 and then Is_For_Access_Subtype (DT)
1221 DT := Base_Type (DT);
1227 elsif Etype (P) /= Any_Type then
1228 Error_Msg_N ("prefix of dereference must be an access type", N);
1233 Get_First_Interp (P, I, It);
1235 while Present (It.Nam) loop
1238 if Is_Access_Type (T) then
1239 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1242 Get_Next_Interp (I, It);
1247 -- Error if no interpretation of the prefix has an access type
1249 if Etype (N) = Any_Type then
1251 ("access type required in prefix of explicit dereference", P);
1252 Set_Etype (N, Any_Type);
1258 and then Nkind (Parent (N)) /= N_Indexed_Component
1260 and then (Nkind (Parent (N)) /= N_Function_Call
1261 or else N /= Name (Parent (N)))
1263 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1264 or else N /= Name (Parent (N)))
1266 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1267 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1269 (Attribute_Name (Parent (N)) /= Name_Address
1271 Attribute_Name (Parent (N)) /= Name_Access))
1273 -- Name is a function call with no actuals, in a context that
1274 -- requires deproceduring (including as an actual in an enclosing
1275 -- function or procedure call). We can conceive of pathological cases
1276 -- where the prefix might include functions that return access to
1277 -- subprograms and others that return a regular type. Disambiguation
1278 -- of those will have to take place in Resolve. See e.g. 7117-014.
1281 Make_Function_Call (Loc,
1282 Name => Make_Explicit_Dereference (Loc, P),
1283 Parameter_Associations => New_List);
1285 -- If the prefix is overloaded, remove operations that have formals,
1286 -- we know that this is a parameterless call.
1288 if Is_Overloaded (P) then
1289 Get_First_Interp (P, I, It);
1290 while Present (It.Nam) loop
1293 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1299 Get_Next_Interp (I, It);
1307 -- A value of remote access-to-class-wide must not be dereferenced
1310 Validate_Remote_Access_To_Class_Wide_Type (N);
1311 end Analyze_Explicit_Dereference;
1313 ------------------------
1314 -- Analyze_Expression --
1315 ------------------------
1317 procedure Analyze_Expression (N : Node_Id) is
1320 Check_Parameterless_Call (N);
1321 end Analyze_Expression;
1323 ------------------------------------
1324 -- Analyze_Indexed_Component_Form --
1325 ------------------------------------
1327 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1328 P : constant Node_Id := Prefix (N);
1329 Exprs : constant List_Id := Expressions (N);
1335 procedure Process_Function_Call;
1336 -- Prefix in indexed component form is an overloadable entity,
1337 -- so the node is a function call. Reformat it as such.
1339 procedure Process_Indexed_Component;
1340 -- Prefix in indexed component form is actually an indexed component.
1341 -- This routine processes it, knowing that the prefix is already
1344 procedure Process_Indexed_Component_Or_Slice;
1345 -- An indexed component with a single index may designate a slice if
1346 -- the index is a subtype mark. This routine disambiguates these two
1347 -- cases by resolving the prefix to see if it is a subtype mark.
1349 procedure Process_Overloaded_Indexed_Component;
1350 -- If the prefix of an indexed component is overloaded, the proper
1351 -- interpretation is selected by the index types and the context.
1353 ---------------------------
1354 -- Process_Function_Call --
1355 ---------------------------
1357 procedure Process_Function_Call is
1361 Change_Node (N, N_Function_Call);
1363 Set_Parameter_Associations (N, Exprs);
1365 Actual := First (Parameter_Associations (N));
1366 while Present (Actual) loop
1368 Check_Parameterless_Call (Actual);
1369 Next_Actual (Actual);
1373 end Process_Function_Call;
1375 -------------------------------
1376 -- Process_Indexed_Component --
1377 -------------------------------
1379 procedure Process_Indexed_Component is
1381 Array_Type : Entity_Id;
1383 Pent : Entity_Id := Empty;
1386 Exp := First (Exprs);
1388 if Is_Overloaded (P) then
1389 Process_Overloaded_Indexed_Component;
1392 Array_Type := Etype (P);
1394 if Is_Entity_Name (P) then
1396 elsif Nkind (P) = N_Selected_Component
1397 and then Is_Entity_Name (Selector_Name (P))
1399 Pent := Entity (Selector_Name (P));
1402 -- Prefix must be appropriate for an array type, taking into
1403 -- account a possible implicit dereference.
1405 if Is_Access_Type (Array_Type) then
1406 Array_Type := Designated_Type (Array_Type);
1407 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1408 Process_Implicit_Dereference_Prefix (Pent, P);
1411 if Is_Array_Type (Array_Type) then
1414 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1416 Set_Etype (N, Any_Type);
1418 if not Has_Compatible_Type
1419 (Exp, Entry_Index_Type (Pent))
1421 Error_Msg_N ("invalid index type in entry name", N);
1423 elsif Present (Next (Exp)) then
1424 Error_Msg_N ("too many subscripts in entry reference", N);
1427 Set_Etype (N, Etype (P));
1432 elsif Is_Record_Type (Array_Type)
1433 and then Remote_AST_I_Dereference (P)
1437 elsif Array_Type = Any_Type then
1438 Set_Etype (N, Any_Type);
1441 -- Here we definitely have a bad indexing
1444 if Nkind (Parent (N)) = N_Requeue_Statement
1445 and then Present (Pent) and then Ekind (Pent) = E_Entry
1448 ("REQUEUE does not permit parameters", First (Exprs));
1450 elsif Is_Entity_Name (P)
1451 and then Etype (P) = Standard_Void_Type
1453 Error_Msg_NE ("incorrect use of&", P, Entity (P));
1456 Error_Msg_N ("array type required in indexed component", P);
1459 Set_Etype (N, Any_Type);
1463 Index := First_Index (Array_Type);
1465 while Present (Index) and then Present (Exp) loop
1466 if not Has_Compatible_Type (Exp, Etype (Index)) then
1467 Wrong_Type (Exp, Etype (Index));
1468 Set_Etype (N, Any_Type);
1476 Set_Etype (N, Component_Type (Array_Type));
1478 if Present (Index) then
1480 ("too few subscripts in array reference", First (Exprs));
1482 elsif Present (Exp) then
1483 Error_Msg_N ("too many subscripts in array reference", Exp);
1486 end Process_Indexed_Component;
1488 ----------------------------------------
1489 -- Process_Indexed_Component_Or_Slice --
1490 ----------------------------------------
1492 procedure Process_Indexed_Component_Or_Slice is
1494 Exp := First (Exprs);
1495 while Present (Exp) loop
1496 Analyze_Expression (Exp);
1500 Exp := First (Exprs);
1502 -- If one index is present, and it is a subtype name, then the
1503 -- node denotes a slice (note that the case of an explicit range
1504 -- for a slice was already built as an N_Slice node in the first
1505 -- place, so that case is not handled here).
1507 -- We use a replace rather than a rewrite here because this is one
1508 -- of the cases in which the tree built by the parser is plain wrong.
1511 and then Is_Entity_Name (Exp)
1512 and then Is_Type (Entity (Exp))
1515 Make_Slice (Sloc (N),
1517 Discrete_Range => New_Copy (Exp)));
1520 -- Otherwise (more than one index present, or single index is not
1521 -- a subtype name), then we have the indexed component case.
1524 Process_Indexed_Component;
1526 end Process_Indexed_Component_Or_Slice;
1528 ------------------------------------------
1529 -- Process_Overloaded_Indexed_Component --
1530 ------------------------------------------
1532 procedure Process_Overloaded_Indexed_Component is
1541 Set_Etype (N, Any_Type);
1543 Get_First_Interp (P, I, It);
1544 while Present (It.Nam) loop
1547 if Is_Access_Type (Typ) then
1548 Typ := Designated_Type (Typ);
1549 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1552 if Is_Array_Type (Typ) then
1554 -- Got a candidate: verify that index types are compatible
1556 Index := First_Index (Typ);
1558 Exp := First (Exprs);
1559 while Present (Index) and then Present (Exp) loop
1560 if Has_Compatible_Type (Exp, Etype (Index)) then
1572 if Found and then No (Index) and then No (Exp) then
1574 Etype (Component_Type (Typ)),
1575 Etype (Component_Type (Typ)));
1579 Get_Next_Interp (I, It);
1582 if Etype (N) = Any_Type then
1583 Error_Msg_N ("no legal interpetation for indexed component", N);
1584 Set_Is_Overloaded (N, False);
1588 end Process_Overloaded_Indexed_Component;
1590 -- Start of processing for Analyze_Indexed_Component_Form
1593 -- Get name of array, function or type
1596 if Nkind (N) = N_Function_Call
1597 or else Nkind (N) = N_Procedure_Call_Statement
1599 -- If P is an explicit dereference whose prefix is of a
1600 -- remote access-to-subprogram type, then N has already
1601 -- been rewritten as a subprogram call and analyzed.
1606 pragma Assert (Nkind (N) = N_Indexed_Component);
1608 P_T := Base_Type (Etype (P));
1610 if Is_Entity_Name (P)
1611 or else Nkind (P) = N_Operator_Symbol
1615 if Ekind (U_N) in Type_Kind then
1617 -- Reformat node as a type conversion
1619 E := Remove_Head (Exprs);
1621 if Present (First (Exprs)) then
1623 ("argument of type conversion must be single expression", N);
1626 Change_Node (N, N_Type_Conversion);
1627 Set_Subtype_Mark (N, P);
1629 Set_Expression (N, E);
1631 -- After changing the node, call for the specific Analysis
1632 -- routine directly, to avoid a double call to the expander.
1634 Analyze_Type_Conversion (N);
1638 if Is_Overloadable (U_N) then
1639 Process_Function_Call;
1641 elsif Ekind (Etype (P)) = E_Subprogram_Type
1642 or else (Is_Access_Type (Etype (P))
1644 Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type)
1646 -- Call to access_to-subprogram with possible implicit dereference
1648 Process_Function_Call;
1650 elsif Is_Generic_Subprogram (U_N) then
1652 -- A common beginner's (or C++ templates fan) error
1654 Error_Msg_N ("generic subprogram cannot be called", N);
1655 Set_Etype (N, Any_Type);
1659 Process_Indexed_Component_Or_Slice;
1662 -- If not an entity name, prefix is an expression that may denote
1663 -- an array or an access-to-subprogram.
1666 if Ekind (P_T) = E_Subprogram_Type
1667 or else (Is_Access_Type (P_T)
1669 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
1671 Process_Function_Call;
1673 elsif Nkind (P) = N_Selected_Component
1674 and then Is_Overloadable (Entity (Selector_Name (P)))
1676 Process_Function_Call;
1679 -- Indexed component, slice, or a call to a member of a family
1680 -- entry, which will be converted to an entry call later.
1682 Process_Indexed_Component_Or_Slice;
1685 end Analyze_Indexed_Component_Form;
1687 ------------------------
1688 -- Analyze_Logical_Op --
1689 ------------------------
1691 procedure Analyze_Logical_Op (N : Node_Id) is
1692 L : constant Node_Id := Left_Opnd (N);
1693 R : constant Node_Id := Right_Opnd (N);
1694 Op_Id : Entity_Id := Entity (N);
1697 Set_Etype (N, Any_Type);
1698 Candidate_Type := Empty;
1700 Analyze_Expression (L);
1701 Analyze_Expression (R);
1703 if Present (Op_Id) then
1705 if Ekind (Op_Id) = E_Operator then
1706 Find_Boolean_Types (L, R, Op_Id, N);
1708 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1712 Op_Id := Get_Name_Entity_Id (Chars (N));
1714 while Present (Op_Id) loop
1715 if Ekind (Op_Id) = E_Operator then
1716 Find_Boolean_Types (L, R, Op_Id, N);
1718 Analyze_User_Defined_Binary_Op (N, Op_Id);
1721 Op_Id := Homonym (Op_Id);
1726 end Analyze_Logical_Op;
1728 ---------------------------
1729 -- Analyze_Membership_Op --
1730 ---------------------------
1732 procedure Analyze_Membership_Op (N : Node_Id) is
1733 L : constant Node_Id := Left_Opnd (N);
1734 R : constant Node_Id := Right_Opnd (N);
1736 Index : Interp_Index;
1738 Found : Boolean := False;
1742 procedure Try_One_Interp (T1 : Entity_Id);
1743 -- Routine to try one proposed interpretation. Note that the context
1744 -- of the operation plays no role in resolving the arguments, so that
1745 -- if there is more than one interpretation of the operands that is
1746 -- compatible with a membership test, the operation is ambiguous.
1748 --------------------
1749 -- Try_One_Interp --
1750 --------------------
1752 procedure Try_One_Interp (T1 : Entity_Id) is
1754 if Has_Compatible_Type (R, T1) then
1756 and then Base_Type (T1) /= Base_Type (T_F)
1758 It := Disambiguate (L, I_F, Index, Any_Type);
1760 if It = No_Interp then
1761 Ambiguous_Operands (N);
1762 Set_Etype (L, Any_Type);
1780 -- Start of processing for Analyze_Membership_Op
1783 Analyze_Expression (L);
1785 if Nkind (R) = N_Range
1786 or else (Nkind (R) = N_Attribute_Reference
1787 and then Attribute_Name (R) = Name_Range)
1791 if not Is_Overloaded (L) then
1792 Try_One_Interp (Etype (L));
1795 Get_First_Interp (L, Index, It);
1797 while Present (It.Typ) loop
1798 Try_One_Interp (It.Typ);
1799 Get_Next_Interp (Index, It);
1803 -- If not a range, it can only be a subtype mark, or else there
1804 -- is a more basic error, to be diagnosed in Find_Type.
1809 if Is_Entity_Name (R) then
1810 Check_Fully_Declared (Entity (R), R);
1814 -- Compatibility between expression and subtype mark or range is
1815 -- checked during resolution. The result of the operation is Boolean
1818 Set_Etype (N, Standard_Boolean);
1819 end Analyze_Membership_Op;
1821 ----------------------
1822 -- Analyze_Negation --
1823 ----------------------
1825 procedure Analyze_Negation (N : Node_Id) is
1826 R : constant Node_Id := Right_Opnd (N);
1827 Op_Id : Entity_Id := Entity (N);
1830 Set_Etype (N, Any_Type);
1831 Candidate_Type := Empty;
1833 Analyze_Expression (R);
1835 if Present (Op_Id) then
1836 if Ekind (Op_Id) = E_Operator then
1837 Find_Negation_Types (R, Op_Id, N);
1839 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1843 Op_Id := Get_Name_Entity_Id (Chars (N));
1844 while Present (Op_Id) loop
1845 if Ekind (Op_Id) = E_Operator then
1846 Find_Negation_Types (R, Op_Id, N);
1848 Analyze_User_Defined_Unary_Op (N, Op_Id);
1851 Op_Id := Homonym (Op_Id);
1856 end Analyze_Negation;
1862 procedure Analyze_Null (N : Node_Id) is
1864 Set_Etype (N, Any_Access);
1867 ----------------------
1868 -- Analyze_One_Call --
1869 ----------------------
1871 procedure Analyze_One_Call
1875 Success : out Boolean)
1877 Actuals : constant List_Id := Parameter_Associations (N);
1878 Prev_T : constant Entity_Id := Etype (N);
1881 Is_Indexed : Boolean := False;
1882 Subp_Type : constant Entity_Id := Etype (Nam);
1885 procedure Indicate_Name_And_Type;
1886 -- If candidate interpretation matches, indicate name and type of
1887 -- result on call node.
1889 ----------------------------
1890 -- Indicate_Name_And_Type --
1891 ----------------------------
1893 procedure Indicate_Name_And_Type is
1895 Add_One_Interp (N, Nam, Etype (Nam));
1898 -- If the prefix of the call is a name, indicate the entity
1899 -- being called. If it is not a name, it is an expression that
1900 -- denotes an access to subprogram or else an entry or family. In
1901 -- the latter case, the name is a selected component, and the entity
1902 -- being called is noted on the selector.
1904 if not Is_Type (Nam) then
1905 if Is_Entity_Name (Name (N))
1906 or else Nkind (Name (N)) = N_Operator_Symbol
1908 Set_Entity (Name (N), Nam);
1910 elsif Nkind (Name (N)) = N_Selected_Component then
1911 Set_Entity (Selector_Name (Name (N)), Nam);
1915 if Debug_Flag_E and not Report then
1916 Write_Str (" Overloaded call ");
1917 Write_Int (Int (N));
1918 Write_Str (" compatible with ");
1919 Write_Int (Int (Nam));
1922 end Indicate_Name_And_Type;
1924 -- Start of processing for Analyze_One_Call
1929 -- If the subprogram has no formals, or if all the formals have
1930 -- defaults, and the return type is an array type, the node may
1931 -- denote an indexing of the result of a parameterless call.
1933 if Needs_No_Actuals (Nam)
1934 and then Present (Actuals)
1936 if Is_Array_Type (Subp_Type) then
1937 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type);
1939 elsif Is_Access_Type (Subp_Type)
1940 and then Is_Array_Type (Designated_Type (Subp_Type))
1943 Try_Indexed_Call (N, Nam, Designated_Type (Subp_Type));
1945 elsif Is_Access_Type (Subp_Type)
1946 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
1948 Is_Indexed := Try_Indirect_Call (N, Nam, Subp_Type);
1953 Normalize_Actuals (N, Nam, (Report and not Is_Indexed), Norm_OK);
1957 -- Mismatch in number or names of parameters
1959 if Debug_Flag_E then
1960 Write_Str (" normalization fails in call ");
1961 Write_Int (Int (N));
1962 Write_Str (" with subprogram ");
1963 Write_Int (Int (Nam));
1967 -- If the context expects a function call, discard any interpretation
1968 -- that is a procedure. If the node is not overloaded, leave as is for
1969 -- better error reporting when type mismatch is found.
1971 elsif Nkind (N) = N_Function_Call
1972 and then Is_Overloaded (Name (N))
1973 and then Ekind (Nam) = E_Procedure
1977 -- Ditto for function calls in a procedure context
1979 elsif Nkind (N) = N_Procedure_Call_Statement
1980 and then Is_Overloaded (Name (N))
1981 and then Etype (Nam) /= Standard_Void_Type
1985 elsif not Present (Actuals) then
1987 -- If Normalize succeeds, then there are default parameters for
1990 Indicate_Name_And_Type;
1992 elsif Ekind (Nam) = E_Operator then
1993 if Nkind (N) = N_Procedure_Call_Statement then
1997 -- This can occur when the prefix of the call is an operator
1998 -- name or an expanded name whose selector is an operator name.
2000 Analyze_Operator_Call (N, Nam);
2002 if Etype (N) /= Prev_T then
2004 -- There may be a user-defined operator that hides the
2005 -- current interpretation. We must check for this independently
2006 -- of the analysis of the call with the user-defined operation,
2007 -- because the parameter names may be wrong and yet the hiding
2008 -- takes place. Fixes b34014o.
2010 if Is_Overloaded (Name (N)) then
2016 Get_First_Interp (Name (N), I, It);
2017 while Present (It.Nam) loop
2018 if Ekind (It.Nam) /= E_Operator
2019 and then Hides_Op (It.Nam, Nam)
2022 (First_Actual (N), Etype (First_Formal (It.Nam)))
2023 and then (No (Next_Actual (First_Actual (N)))
2024 or else Has_Compatible_Type
2025 (Next_Actual (First_Actual (N)),
2026 Etype (Next_Formal (First_Formal (It.Nam)))))
2028 Set_Etype (N, Prev_T);
2032 Get_Next_Interp (I, It);
2037 -- If operator matches formals, record its name on the call.
2038 -- If the operator is overloaded, Resolve will select the
2039 -- correct one from the list of interpretations. The call
2040 -- node itself carries the first candidate.
2042 Set_Entity (Name (N), Nam);
2045 elsif Report and then Etype (N) = Any_Type then
2046 Error_Msg_N ("incompatible arguments for operator", N);
2050 -- Normalize_Actuals has chained the named associations in the
2051 -- correct order of the formals.
2053 Actual := First_Actual (N);
2054 Formal := First_Formal (Nam);
2055 while Present (Actual) and then Present (Formal) loop
2056 if Nkind (Parent (Actual)) /= N_Parameter_Association
2057 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2059 if Has_Compatible_Type (Actual, Etype (Formal)) then
2060 Next_Actual (Actual);
2061 Next_Formal (Formal);
2064 if Debug_Flag_E then
2065 Write_Str (" type checking fails in call ");
2066 Write_Int (Int (N));
2067 Write_Str (" with formal ");
2068 Write_Int (Int (Formal));
2069 Write_Str (" in subprogram ");
2070 Write_Int (Int (Nam));
2074 if Report and not Is_Indexed then
2075 Wrong_Type (Actual, Etype (Formal));
2077 if Nkind (Actual) = N_Op_Eq
2078 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2080 Formal := First_Formal (Nam);
2082 while Present (Formal) loop
2084 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2086 ("possible misspelling of `='>`!", Actual);
2090 Next_Formal (Formal);
2094 if All_Errors_Mode then
2095 Error_Msg_Sloc := Sloc (Nam);
2097 if Is_Overloadable (Nam)
2098 and then Present (Alias (Nam))
2099 and then not Comes_From_Source (Nam)
2102 (" =='> in call to &#(inherited)!", Actual, Nam);
2104 elsif Ekind (Nam) = E_Subprogram_Type then
2106 Access_To_Subprogram_Typ :
2107 constant Entity_Id :=
2109 (Associated_Node_For_Itype (Nam));
2112 " =='> in call to dereference of &#!",
2113 Actual, Access_To_Subprogram_Typ);
2117 Error_Msg_NE (" =='> in call to &#!", Actual, Nam);
2127 -- Normalize_Actuals has verified that a default value exists
2128 -- for this formal. Current actual names a subsequent formal.
2130 Next_Formal (Formal);
2134 -- On exit, all actuals match
2136 Indicate_Name_And_Type;
2138 end Analyze_One_Call;
2140 ---------------------------
2141 -- Analyze_Operator_Call --
2142 ---------------------------
2144 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2145 Op_Name : constant Name_Id := Chars (Op_Id);
2146 Act1 : constant Node_Id := First_Actual (N);
2147 Act2 : constant Node_Id := Next_Actual (Act1);
2150 -- Binary operator case
2152 if Present (Act2) then
2154 -- If more than two operands, then not binary operator after all
2156 if Present (Next_Actual (Act2)) then
2159 elsif Op_Name = Name_Op_Add
2160 or else Op_Name = Name_Op_Subtract
2161 or else Op_Name = Name_Op_Multiply
2162 or else Op_Name = Name_Op_Divide
2163 or else Op_Name = Name_Op_Mod
2164 or else Op_Name = Name_Op_Rem
2165 or else Op_Name = Name_Op_Expon
2167 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2169 elsif Op_Name = Name_Op_And
2170 or else Op_Name = Name_Op_Or
2171 or else Op_Name = Name_Op_Xor
2173 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2175 elsif Op_Name = Name_Op_Lt
2176 or else Op_Name = Name_Op_Le
2177 or else Op_Name = Name_Op_Gt
2178 or else Op_Name = Name_Op_Ge
2180 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2182 elsif Op_Name = Name_Op_Eq
2183 or else Op_Name = Name_Op_Ne
2185 Find_Equality_Types (Act1, Act2, Op_Id, N);
2187 elsif Op_Name = Name_Op_Concat then
2188 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2190 -- Is this else null correct, or should it be an abort???
2196 -- Unary operator case
2199 if Op_Name = Name_Op_Subtract or else
2200 Op_Name = Name_Op_Add or else
2201 Op_Name = Name_Op_Abs
2203 Find_Unary_Types (Act1, Op_Id, N);
2206 Op_Name = Name_Op_Not
2208 Find_Negation_Types (Act1, Op_Id, N);
2210 -- Is this else null correct, or should it be an abort???
2216 end Analyze_Operator_Call;
2218 -------------------------------------------
2219 -- Analyze_Overloaded_Selected_Component --
2220 -------------------------------------------
2222 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
2223 Nam : constant Node_Id := Prefix (N);
2224 Sel : constant Node_Id := Selector_Name (N);
2231 Set_Etype (Sel, Any_Type);
2233 Get_First_Interp (Nam, I, It);
2234 while Present (It.Typ) loop
2235 if Is_Access_Type (It.Typ) then
2236 T := Designated_Type (It.Typ);
2237 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2242 if Is_Record_Type (T) then
2243 Comp := First_Entity (T);
2244 while Present (Comp) loop
2245 if Chars (Comp) = Chars (Sel)
2246 and then Is_Visible_Component (Comp)
2248 Set_Entity_With_Style_Check (Sel, Comp);
2249 Generate_Reference (Comp, Sel);
2251 Set_Etype (Sel, Etype (Comp));
2252 Add_One_Interp (N, Etype (Comp), Etype (Comp));
2254 -- This also specifies a candidate to resolve the name.
2255 -- Further overloading will be resolved from context.
2257 Set_Etype (Nam, It.Typ);
2263 elsif Is_Concurrent_Type (T) then
2264 Comp := First_Entity (T);
2265 while Present (Comp)
2266 and then Comp /= First_Private_Entity (T)
2268 if Chars (Comp) = Chars (Sel) then
2269 if Is_Overloadable (Comp) then
2270 Add_One_Interp (Sel, Comp, Etype (Comp));
2272 Set_Entity_With_Style_Check (Sel, Comp);
2273 Generate_Reference (Comp, Sel);
2276 Set_Etype (Sel, Etype (Comp));
2277 Set_Etype (N, Etype (Comp));
2278 Set_Etype (Nam, It.Typ);
2280 -- For access type case, introduce explicit deference for
2281 -- more uniform treatment of entry calls.
2283 if Is_Access_Type (Etype (Nam)) then
2284 Insert_Explicit_Dereference (Nam);
2286 (Warn_On_Dereference, "?implicit dereference", N);
2293 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2296 Get_Next_Interp (I, It);
2299 if Etype (N) = Any_Type then
2300 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
2301 Set_Entity (Sel, Any_Id);
2302 Set_Etype (Sel, Any_Type);
2304 end Analyze_Overloaded_Selected_Component;
2306 ----------------------------------
2307 -- Analyze_Qualified_Expression --
2308 ----------------------------------
2310 procedure Analyze_Qualified_Expression (N : Node_Id) is
2311 Mark : constant Entity_Id := Subtype_Mark (N);
2315 Set_Etype (N, Any_Type);
2319 if T = Any_Type then
2323 Check_Fully_Declared (T, N);
2324 Analyze_Expression (Expression (N));
2326 end Analyze_Qualified_Expression;
2332 procedure Analyze_Range (N : Node_Id) is
2333 L : constant Node_Id := Low_Bound (N);
2334 H : constant Node_Id := High_Bound (N);
2335 I1, I2 : Interp_Index;
2338 procedure Check_Common_Type (T1, T2 : Entity_Id);
2339 -- Verify the compatibility of two types, and choose the
2340 -- non universal one if the other is universal.
2342 procedure Check_High_Bound (T : Entity_Id);
2343 -- Test one interpretation of the low bound against all those
2344 -- of the high bound.
2346 procedure Check_Universal_Expression (N : Node_Id);
2347 -- In Ada83, reject bounds of a universal range that are not
2348 -- literals or entity names.
2350 -----------------------
2351 -- Check_Common_Type --
2352 -----------------------
2354 procedure Check_Common_Type (T1, T2 : Entity_Id) is
2356 if Covers (T1, T2) or else Covers (T2, T1) then
2357 if T1 = Universal_Integer
2358 or else T1 = Universal_Real
2359 or else T1 = Any_Character
2361 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
2364 Add_One_Interp (N, T1, T1);
2367 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
2370 end Check_Common_Type;
2372 ----------------------
2373 -- Check_High_Bound --
2374 ----------------------
2376 procedure Check_High_Bound (T : Entity_Id) is
2378 if not Is_Overloaded (H) then
2379 Check_Common_Type (T, Etype (H));
2381 Get_First_Interp (H, I2, It2);
2382 while Present (It2.Typ) loop
2383 Check_Common_Type (T, It2.Typ);
2384 Get_Next_Interp (I2, It2);
2387 end Check_High_Bound;
2389 -----------------------------
2390 -- Is_Universal_Expression --
2391 -----------------------------
2393 procedure Check_Universal_Expression (N : Node_Id) is
2395 if Etype (N) = Universal_Integer
2396 and then Nkind (N) /= N_Integer_Literal
2397 and then not Is_Entity_Name (N)
2398 and then Nkind (N) /= N_Attribute_Reference
2400 Error_Msg_N ("illegal bound in discrete range", N);
2402 end Check_Universal_Expression;
2404 -- Start of processing for Analyze_Range
2407 Set_Etype (N, Any_Type);
2408 Analyze_Expression (L);
2409 Analyze_Expression (H);
2411 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
2415 if not Is_Overloaded (L) then
2416 Check_High_Bound (Etype (L));
2418 Get_First_Interp (L, I1, It1);
2419 while Present (It1.Typ) loop
2420 Check_High_Bound (It1.Typ);
2421 Get_Next_Interp (I1, It1);
2425 -- If result is Any_Type, then we did not find a compatible pair
2427 if Etype (N) = Any_Type then
2428 Error_Msg_N ("incompatible types in range ", N);
2432 if Ada_Version = Ada_83
2434 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
2435 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
2437 Check_Universal_Expression (L);
2438 Check_Universal_Expression (H);
2442 -----------------------
2443 -- Analyze_Reference --
2444 -----------------------
2446 procedure Analyze_Reference (N : Node_Id) is
2447 P : constant Node_Id := Prefix (N);
2448 Acc_Type : Entity_Id;
2451 Acc_Type := Create_Itype (E_Allocator_Type, N);
2452 Set_Etype (Acc_Type, Acc_Type);
2453 Init_Size_Align (Acc_Type);
2454 Set_Directly_Designated_Type (Acc_Type, Etype (P));
2455 Set_Etype (N, Acc_Type);
2456 end Analyze_Reference;
2458 --------------------------------
2459 -- Analyze_Selected_Component --
2460 --------------------------------
2462 -- Prefix is a record type or a task or protected type. In the
2463 -- later case, the selector must denote a visible entry.
2465 procedure Analyze_Selected_Component (N : Node_Id) is
2466 Name : constant Node_Id := Prefix (N);
2467 Sel : constant Node_Id := Selector_Name (N);
2469 Entity_List : Entity_Id;
2470 Prefix_Type : Entity_Id;
2471 Pent : Entity_Id := Empty;
2476 -- Start of processing for Analyze_Selected_Component
2479 Set_Etype (N, Any_Type);
2481 if Is_Overloaded (Name) then
2482 Analyze_Overloaded_Selected_Component (N);
2485 elsif Etype (Name) = Any_Type then
2486 Set_Entity (Sel, Any_Id);
2487 Set_Etype (Sel, Any_Type);
2491 -- Function calls that are prefixes of selected components must be
2492 -- fully resolved in case we need to build an actual subtype, or
2493 -- do some other operation requiring a fully resolved prefix.
2495 -- Note: Resolving all Nkinds of nodes here doesn't work.
2496 -- (Breaks 2129-008) ???.
2498 if Nkind (Name) = N_Function_Call then
2502 Prefix_Type := Etype (Name);
2505 if Is_Access_Type (Prefix_Type) then
2507 -- A RACW object can never be used as prefix of a selected
2508 -- component since that means it is dereferenced without
2509 -- being a controlling operand of a dispatching operation
2512 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
2513 and then Comes_From_Source (N)
2516 ("invalid dereference of a remote access to class-wide value",
2519 -- Normal case of selected component applied to access type
2522 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2524 if Is_Entity_Name (Name) then
2525 Pent := Entity (Name);
2526 elsif Nkind (Name) = N_Selected_Component
2527 and then Is_Entity_Name (Selector_Name (Name))
2529 Pent := Entity (Selector_Name (Name));
2532 Process_Implicit_Dereference_Prefix (Pent, Name);
2535 Prefix_Type := Designated_Type (Prefix_Type);
2538 if Ekind (Prefix_Type) = E_Private_Subtype then
2539 Prefix_Type := Base_Type (Prefix_Type);
2542 Entity_List := Prefix_Type;
2544 -- For class-wide types, use the entity list of the root type. This
2545 -- indirection is specially important for private extensions because
2546 -- only the root type get switched (not the class-wide type).
2548 if Is_Class_Wide_Type (Prefix_Type) then
2549 Entity_List := Root_Type (Prefix_Type);
2552 Comp := First_Entity (Entity_List);
2554 -- If the selector has an original discriminant, the node appears in
2555 -- an instance. Replace the discriminant with the corresponding one
2556 -- in the current discriminated type. For nested generics, this must
2557 -- be done transitively, so note the new original discriminant.
2559 if Nkind (Sel) = N_Identifier
2560 and then Present (Original_Discriminant (Sel))
2562 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
2564 -- Mark entity before rewriting, for completeness and because
2565 -- subsequent semantic checks might examine the original node.
2567 Set_Entity (Sel, Comp);
2568 Rewrite (Selector_Name (N),
2569 New_Occurrence_Of (Comp, Sloc (N)));
2570 Set_Original_Discriminant (Selector_Name (N), Comp);
2571 Set_Etype (N, Etype (Comp));
2573 if Is_Access_Type (Etype (Name)) then
2574 Insert_Explicit_Dereference (Name);
2575 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2578 elsif Is_Record_Type (Prefix_Type) then
2580 -- Find component with given name
2582 while Present (Comp) loop
2583 if Chars (Comp) = Chars (Sel)
2584 and then Is_Visible_Component (Comp)
2586 Set_Entity_With_Style_Check (Sel, Comp);
2587 Generate_Reference (Comp, Sel);
2589 Set_Etype (Sel, Etype (Comp));
2591 if Ekind (Comp) = E_Discriminant then
2592 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
2594 ("cannot reference discriminant of Unchecked_Union",
2598 if Is_Generic_Type (Prefix_Type)
2600 Is_Generic_Type (Root_Type (Prefix_Type))
2602 Set_Original_Discriminant (Sel, Comp);
2606 -- Resolve the prefix early otherwise it is not possible to
2607 -- build the actual subtype of the component: it may need
2608 -- to duplicate this prefix and duplication is only allowed
2609 -- on fully resolved expressions.
2613 -- We never need an actual subtype for the case of a selection
2614 -- for a indexed component of a non-packed array, since in
2615 -- this case gigi generates all the checks and can find the
2616 -- necessary bounds information.
2618 -- We also do not need an actual subtype for the case of
2619 -- a first, last, length, or range attribute applied to a
2620 -- non-packed array, since gigi can again get the bounds in
2621 -- these cases (gigi cannot handle the packed case, since it
2622 -- has the bounds of the packed array type, not the original
2623 -- bounds of the type). However, if the prefix is itself a
2624 -- selected component, as in a.b.c (i), gigi may regard a.b.c
2625 -- as a dynamic-sized temporary, so we do generate an actual
2626 -- subtype for this case.
2628 Parent_N := Parent (N);
2630 if not Is_Packed (Etype (Comp))
2632 ((Nkind (Parent_N) = N_Indexed_Component
2633 and then Nkind (Name) /= N_Selected_Component)
2635 (Nkind (Parent_N) = N_Attribute_Reference
2636 and then (Attribute_Name (Parent_N) = Name_First
2638 Attribute_Name (Parent_N) = Name_Last
2640 Attribute_Name (Parent_N) = Name_Length
2642 Attribute_Name (Parent_N) = Name_Range)))
2644 Set_Etype (N, Etype (Comp));
2646 -- In all other cases, we currently build an actual subtype. It
2647 -- seems likely that many of these cases can be avoided, but
2648 -- right now, the front end makes direct references to the
2649 -- bounds (e.g. in generating a length check), and if we do
2650 -- not make an actual subtype, we end up getting a direct
2651 -- reference to a discriminant which will not do.
2653 -- Comment needs revision, "in all other cases" does not
2654 -- reasonably describe the situation below with an elsif???
2656 elsif Expander_Active then
2658 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
2659 Insert_Action (N, Act_Decl);
2661 if No (Act_Decl) then
2662 Set_Etype (N, Etype (Comp));
2665 -- Component type depends on discriminants. Enter the
2666 -- main attributes of the subtype.
2669 Subt : constant Entity_Id :=
2670 Defining_Identifier (Act_Decl);
2673 Set_Etype (Subt, Base_Type (Etype (Comp)));
2674 Set_Ekind (Subt, Ekind (Etype (Comp)));
2675 Set_Etype (N, Subt);
2680 Set_Etype (N, Etype (Comp));
2689 -- Ada 2005 (AI-252)
2691 if Ada_Version >= Ada_05
2692 and then Is_Tagged_Type (Prefix_Type)
2693 and then Try_Object_Operation (N)
2697 -- If the transformation fails, it will be necessary
2698 -- to redo the analysis with all errors enabled, to indicate
2699 -- candidate interpretations and reasons for each failure ???
2703 elsif Is_Private_Type (Prefix_Type) then
2705 -- Allow access only to discriminants of the type. If the
2706 -- type has no full view, gigi uses the parent type for
2707 -- the components, so we do the same here.
2709 if No (Full_View (Prefix_Type)) then
2710 Entity_List := Root_Type (Base_Type (Prefix_Type));
2711 Comp := First_Entity (Entity_List);
2714 while Present (Comp) loop
2715 if Chars (Comp) = Chars (Sel) then
2716 if Ekind (Comp) = E_Discriminant then
2717 Set_Entity_With_Style_Check (Sel, Comp);
2718 Generate_Reference (Comp, Sel);
2720 Set_Etype (Sel, Etype (Comp));
2721 Set_Etype (N, Etype (Comp));
2723 if Is_Generic_Type (Prefix_Type)
2725 Is_Generic_Type (Root_Type (Prefix_Type))
2727 Set_Original_Discriminant (Sel, Comp);
2732 ("invisible selector for }",
2733 N, First_Subtype (Prefix_Type));
2734 Set_Entity (Sel, Any_Id);
2735 Set_Etype (N, Any_Type);
2744 elsif Is_Concurrent_Type (Prefix_Type) then
2746 -- Prefix is concurrent type. Find visible operation with given name
2747 -- For a task, this can only include entries or discriminants if
2748 -- the task type is not an enclosing scope. If it is an enclosing
2749 -- scope (e.g. in an inner task) then all entities are visible, but
2750 -- the prefix must denote the enclosing scope, i.e. can only be
2751 -- a direct name or an expanded name.
2753 Set_Etype (Sel, Any_Type);
2754 In_Scope := In_Open_Scopes (Prefix_Type);
2756 while Present (Comp) loop
2757 if Chars (Comp) = Chars (Sel) then
2758 if Is_Overloadable (Comp) then
2759 Add_One_Interp (Sel, Comp, Etype (Comp));
2761 elsif Ekind (Comp) = E_Discriminant
2762 or else Ekind (Comp) = E_Entry_Family
2764 and then Is_Entity_Name (Name))
2766 Set_Entity_With_Style_Check (Sel, Comp);
2767 Generate_Reference (Comp, Sel);
2773 Set_Etype (Sel, Etype (Comp));
2774 Set_Etype (N, Etype (Comp));
2776 if Ekind (Comp) = E_Discriminant then
2777 Set_Original_Discriminant (Sel, Comp);
2780 -- For access type case, introduce explicit deference for
2781 -- more uniform treatment of entry calls.
2783 if Is_Access_Type (Etype (Name)) then
2784 Insert_Explicit_Dereference (Name);
2786 (Warn_On_Dereference, "?implicit dereference", N);
2792 exit when not In_Scope
2794 Comp = First_Private_Entity (Base_Type (Prefix_Type));
2797 Set_Is_Overloaded (N, Is_Overloaded (Sel));
2802 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
2805 -- If N still has no type, the component is not defined in the prefix
2807 if Etype (N) = Any_Type then
2809 -- If the prefix is a single concurrent object, use its name in
2810 -- the error message, rather than that of its anonymous type.
2812 if Is_Concurrent_Type (Prefix_Type)
2813 and then Is_Internal_Name (Chars (Prefix_Type))
2814 and then not Is_Derived_Type (Prefix_Type)
2815 and then Is_Entity_Name (Name)
2818 Error_Msg_Node_2 := Entity (Name);
2819 Error_Msg_NE ("no selector& for&", N, Sel);
2821 Check_Misspelled_Selector (Entity_List, Sel);
2823 elsif Is_Generic_Type (Prefix_Type)
2824 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
2825 and then Prefix_Type /= Etype (Prefix_Type)
2826 and then Is_Record_Type (Etype (Prefix_Type))
2828 -- If this is a derived formal type, the parent may have a
2829 -- different visibility at this point. Try for an inherited
2830 -- component before reporting an error.
2832 Set_Etype (Prefix (N), Etype (Prefix_Type));
2833 Analyze_Selected_Component (N);
2836 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
2837 and then Is_Generic_Actual_Type (Prefix_Type)
2838 and then Present (Full_View (Prefix_Type))
2840 -- Similarly, if this the actual for a formal derived type, the
2841 -- component inherited from the generic parent may not be visible
2842 -- in the actual, but the selected component is legal.
2849 First_Component (Generic_Parent_Type (Parent (Prefix_Type)));
2850 while Present (Comp) loop
2851 if Chars (Comp) = Chars (Sel) then
2852 Set_Entity_With_Style_Check (Sel, Comp);
2853 Set_Etype (Sel, Etype (Comp));
2854 Set_Etype (N, Etype (Comp));
2858 Next_Component (Comp);
2861 pragma Assert (Etype (N) /= Any_Type);
2865 if Ekind (Prefix_Type) = E_Record_Subtype then
2867 -- Check whether this is a component of the base type
2868 -- which is absent from a statically constrained subtype.
2869 -- This will raise constraint error at run-time, but is
2870 -- not a compile-time error. When the selector is illegal
2871 -- for base type as well fall through and generate a
2872 -- compilation error anyway.
2874 Comp := First_Component (Base_Type (Prefix_Type));
2875 while Present (Comp) loop
2876 if Chars (Comp) = Chars (Sel)
2877 and then Is_Visible_Component (Comp)
2879 Set_Entity_With_Style_Check (Sel, Comp);
2880 Generate_Reference (Comp, Sel);
2881 Set_Etype (Sel, Etype (Comp));
2882 Set_Etype (N, Etype (Comp));
2884 -- Emit appropriate message. Gigi will replace the
2885 -- node subsequently with the appropriate Raise.
2887 Apply_Compile_Time_Constraint_Error
2888 (N, "component not present in }?",
2889 CE_Discriminant_Check_Failed,
2890 Ent => Prefix_Type, Rep => False);
2891 Set_Raises_Constraint_Error (N);
2895 Next_Component (Comp);
2900 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
2901 Error_Msg_NE ("no selector& for}", N, Sel);
2903 Check_Misspelled_Selector (Entity_List, Sel);
2907 Set_Entity (Sel, Any_Id);
2908 Set_Etype (Sel, Any_Type);
2910 end Analyze_Selected_Component;
2912 ---------------------------
2913 -- Analyze_Short_Circuit --
2914 ---------------------------
2916 procedure Analyze_Short_Circuit (N : Node_Id) is
2917 L : constant Node_Id := Left_Opnd (N);
2918 R : constant Node_Id := Right_Opnd (N);
2923 Analyze_Expression (L);
2924 Analyze_Expression (R);
2925 Set_Etype (N, Any_Type);
2927 if not Is_Overloaded (L) then
2929 if Root_Type (Etype (L)) = Standard_Boolean
2930 and then Has_Compatible_Type (R, Etype (L))
2932 Add_One_Interp (N, Etype (L), Etype (L));
2936 Get_First_Interp (L, Ind, It);
2938 while Present (It.Typ) loop
2939 if Root_Type (It.Typ) = Standard_Boolean
2940 and then Has_Compatible_Type (R, It.Typ)
2942 Add_One_Interp (N, It.Typ, It.Typ);
2945 Get_Next_Interp (Ind, It);
2949 -- Here we have failed to find an interpretation. Clearly we
2950 -- know that it is not the case that both operands can have
2951 -- an interpretation of Boolean, but this is by far the most
2952 -- likely intended interpretation. So we simply resolve both
2953 -- operands as Booleans, and at least one of these resolutions
2954 -- will generate an error message, and we do not need to give
2955 -- a further error message on the short circuit operation itself.
2957 if Etype (N) = Any_Type then
2958 Resolve (L, Standard_Boolean);
2959 Resolve (R, Standard_Boolean);
2960 Set_Etype (N, Standard_Boolean);
2962 end Analyze_Short_Circuit;
2968 procedure Analyze_Slice (N : Node_Id) is
2969 P : constant Node_Id := Prefix (N);
2970 D : constant Node_Id := Discrete_Range (N);
2971 Array_Type : Entity_Id;
2973 procedure Analyze_Overloaded_Slice;
2974 -- If the prefix is overloaded, select those interpretations that
2975 -- yield a one-dimensional array type.
2977 ------------------------------
2978 -- Analyze_Overloaded_Slice --
2979 ------------------------------
2981 procedure Analyze_Overloaded_Slice is
2987 Set_Etype (N, Any_Type);
2989 Get_First_Interp (P, I, It);
2990 while Present (It.Nam) loop
2993 if Is_Access_Type (Typ) then
2994 Typ := Designated_Type (Typ);
2995 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2998 if Is_Array_Type (Typ)
2999 and then Number_Dimensions (Typ) = 1
3000 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
3002 Add_One_Interp (N, Typ, Typ);
3005 Get_Next_Interp (I, It);
3008 if Etype (N) = Any_Type then
3009 Error_Msg_N ("expect array type in prefix of slice", N);
3011 end Analyze_Overloaded_Slice;
3013 -- Start of processing for Analyze_Slice
3019 if Is_Overloaded (P) then
3020 Analyze_Overloaded_Slice;
3023 Array_Type := Etype (P);
3024 Set_Etype (N, Any_Type);
3026 if Is_Access_Type (Array_Type) then
3027 Array_Type := Designated_Type (Array_Type);
3028 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3031 if not Is_Array_Type (Array_Type) then
3032 Wrong_Type (P, Any_Array);
3034 elsif Number_Dimensions (Array_Type) > 1 then
3036 ("type is not one-dimensional array in slice prefix", N);
3039 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
3041 Wrong_Type (D, Etype (First_Index (Array_Type)));
3044 Set_Etype (N, Array_Type);
3049 -----------------------------
3050 -- Analyze_Type_Conversion --
3051 -----------------------------
3053 procedure Analyze_Type_Conversion (N : Node_Id) is
3054 Expr : constant Node_Id := Expression (N);
3058 -- If Conversion_OK is set, then the Etype is already set, and the
3059 -- only processing required is to analyze the expression. This is
3060 -- used to construct certain "illegal" conversions which are not
3061 -- allowed by Ada semantics, but can be handled OK by Gigi, see
3062 -- Sinfo for further details.
3064 if Conversion_OK (N) then
3069 -- Otherwise full type analysis is required, as well as some semantic
3070 -- checks to make sure the argument of the conversion is appropriate.
3072 Find_Type (Subtype_Mark (N));
3073 T := Entity (Subtype_Mark (N));
3075 Check_Fully_Declared (T, N);
3076 Analyze_Expression (Expr);
3077 Validate_Remote_Type_Type_Conversion (N);
3079 -- Only remaining step is validity checks on the argument. These
3080 -- are skipped if the conversion does not come from the source.
3082 if not Comes_From_Source (N) then
3085 elsif Nkind (Expr) = N_Null then
3086 Error_Msg_N ("argument of conversion cannot be null", N);
3087 Error_Msg_N ("\use qualified expression instead", N);
3088 Set_Etype (N, Any_Type);
3090 elsif Nkind (Expr) = N_Aggregate then
3091 Error_Msg_N ("argument of conversion cannot be aggregate", N);
3092 Error_Msg_N ("\use qualified expression instead", N);
3094 elsif Nkind (Expr) = N_Allocator then
3095 Error_Msg_N ("argument of conversion cannot be an allocator", N);
3096 Error_Msg_N ("\use qualified expression instead", N);
3098 elsif Nkind (Expr) = N_String_Literal then
3099 Error_Msg_N ("argument of conversion cannot be string literal", N);
3100 Error_Msg_N ("\use qualified expression instead", N);
3102 elsif Nkind (Expr) = N_Character_Literal then
3103 if Ada_Version = Ada_83 then
3106 Error_Msg_N ("argument of conversion cannot be character literal",
3108 Error_Msg_N ("\use qualified expression instead", N);
3111 elsif Nkind (Expr) = N_Attribute_Reference
3113 (Attribute_Name (Expr) = Name_Access or else
3114 Attribute_Name (Expr) = Name_Unchecked_Access or else
3115 Attribute_Name (Expr) = Name_Unrestricted_Access)
3117 Error_Msg_N ("argument of conversion cannot be access", N);
3118 Error_Msg_N ("\use qualified expression instead", N);
3120 end Analyze_Type_Conversion;
3122 ----------------------
3123 -- Analyze_Unary_Op --
3124 ----------------------
3126 procedure Analyze_Unary_Op (N : Node_Id) is
3127 R : constant Node_Id := Right_Opnd (N);
3128 Op_Id : Entity_Id := Entity (N);
3131 Set_Etype (N, Any_Type);
3132 Candidate_Type := Empty;
3134 Analyze_Expression (R);
3136 if Present (Op_Id) then
3137 if Ekind (Op_Id) = E_Operator then
3138 Find_Unary_Types (R, Op_Id, N);
3140 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3144 Op_Id := Get_Name_Entity_Id (Chars (N));
3145 while Present (Op_Id) loop
3146 if Ekind (Op_Id) = E_Operator then
3147 if No (Next_Entity (First_Entity (Op_Id))) then
3148 Find_Unary_Types (R, Op_Id, N);
3151 elsif Is_Overloadable (Op_Id) then
3152 Analyze_User_Defined_Unary_Op (N, Op_Id);
3155 Op_Id := Homonym (Op_Id);
3160 end Analyze_Unary_Op;
3162 ----------------------------------
3163 -- Analyze_Unchecked_Expression --
3164 ----------------------------------
3166 procedure Analyze_Unchecked_Expression (N : Node_Id) is
3168 Analyze (Expression (N), Suppress => All_Checks);
3169 Set_Etype (N, Etype (Expression (N)));
3170 Save_Interps (Expression (N), N);
3171 end Analyze_Unchecked_Expression;
3173 ---------------------------------------
3174 -- Analyze_Unchecked_Type_Conversion --
3175 ---------------------------------------
3177 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
3179 Find_Type (Subtype_Mark (N));
3180 Analyze_Expression (Expression (N));
3181 Set_Etype (N, Entity (Subtype_Mark (N)));
3182 end Analyze_Unchecked_Type_Conversion;
3184 ------------------------------------
3185 -- Analyze_User_Defined_Binary_Op --
3186 ------------------------------------
3188 procedure Analyze_User_Defined_Binary_Op
3193 -- Only do analysis if the operator Comes_From_Source, since otherwise
3194 -- the operator was generated by the expander, and all such operators
3195 -- always refer to the operators in package Standard.
3197 if Comes_From_Source (N) then
3199 F1 : constant Entity_Id := First_Formal (Op_Id);
3200 F2 : constant Entity_Id := Next_Formal (F1);
3203 -- Verify that Op_Id is a visible binary function. Note that since
3204 -- we know Op_Id is overloaded, potentially use visible means use
3205 -- visible for sure (RM 9.4(11)).
3207 if Ekind (Op_Id) = E_Function
3208 and then Present (F2)
3209 and then (Is_Immediately_Visible (Op_Id)
3210 or else Is_Potentially_Use_Visible (Op_Id))
3211 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
3212 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
3214 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3216 if Debug_Flag_E then
3217 Write_Str ("user defined operator ");
3218 Write_Name (Chars (Op_Id));
3219 Write_Str (" on node ");
3220 Write_Int (Int (N));
3226 end Analyze_User_Defined_Binary_Op;
3228 -----------------------------------
3229 -- Analyze_User_Defined_Unary_Op --
3230 -----------------------------------
3232 procedure Analyze_User_Defined_Unary_Op
3237 -- Only do analysis if the operator Comes_From_Source, since otherwise
3238 -- the operator was generated by the expander, and all such operators
3239 -- always refer to the operators in package Standard.
3241 if Comes_From_Source (N) then
3243 F : constant Entity_Id := First_Formal (Op_Id);
3246 -- Verify that Op_Id is a visible unary function. Note that since
3247 -- we know Op_Id is overloaded, potentially use visible means use
3248 -- visible for sure (RM 9.4(11)).
3250 if Ekind (Op_Id) = E_Function
3251 and then No (Next_Formal (F))
3252 and then (Is_Immediately_Visible (Op_Id)
3253 or else Is_Potentially_Use_Visible (Op_Id))
3254 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
3256 Add_One_Interp (N, Op_Id, Etype (Op_Id));
3260 end Analyze_User_Defined_Unary_Op;
3262 ---------------------------
3263 -- Check_Arithmetic_Pair --
3264 ---------------------------
3266 procedure Check_Arithmetic_Pair
3267 (T1, T2 : Entity_Id;
3271 Op_Name : constant Name_Id := Chars (Op_Id);
3273 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
3274 -- Check whether the fixed-point type Typ has a user-defined operator
3275 -- (multiplication or division) that should hide the corresponding
3276 -- predefined operator. Used to implement Ada 2005 AI-264, to make
3277 -- such operators more visible and therefore useful.
3279 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
3280 -- Get specific type (i.e. non-universal type if there is one)
3286 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
3292 -- The operation is treated as primitive if it is declared in the
3293 -- same scope as the type, and therefore on the same entity chain.
3295 Ent := Next_Entity (Typ);
3296 while Present (Ent) loop
3297 if Chars (Ent) = Chars (Op) then
3298 F1 := First_Formal (Ent);
3299 F2 := Next_Formal (F1);
3301 -- The operation counts as primitive if either operand or
3302 -- result are of the given type, and both operands are fixed
3305 if (Etype (F1) = Typ
3306 and then Is_Fixed_Point_Type (Etype (F2)))
3310 and then Is_Fixed_Point_Type (Etype (F1)))
3314 and then Is_Fixed_Point_Type (Etype (F1))
3315 and then Is_Fixed_Point_Type (Etype (F2)))
3331 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
3333 if T1 = Universal_Integer or else T1 = Universal_Real then
3334 return Base_Type (T2);
3336 return Base_Type (T1);
3340 -- Start of processing for Check_Arithmetic_Pair
3343 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
3345 if Is_Numeric_Type (T1)
3346 and then Is_Numeric_Type (T2)
3347 and then (Covers (T1, T2) or else Covers (T2, T1))
3349 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3352 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
3354 if Is_Fixed_Point_Type (T1)
3355 and then (Is_Fixed_Point_Type (T2)
3356 or else T2 = Universal_Real)
3358 -- If Treat_Fixed_As_Integer is set then the Etype is already set
3359 -- and no further processing is required (this is the case of an
3360 -- operator constructed by Exp_Fixd for a fixed point operation)
3361 -- Otherwise add one interpretation with universal fixed result
3362 -- If the operator is given in functional notation, it comes
3363 -- from source and Fixed_As_Integer cannot apply.
3365 if (Nkind (N) not in N_Op
3366 or else not Treat_Fixed_As_Integer (N))
3368 (not (Ada_Version >= Ada_05 and then Has_Fixed_Op (T1, Op_Id))
3369 or else Nkind (Parent (N)) = N_Type_Conversion)
3371 Add_One_Interp (N, Op_Id, Universal_Fixed);
3374 elsif Is_Fixed_Point_Type (T2)
3375 and then (Nkind (N) not in N_Op
3376 or else not Treat_Fixed_As_Integer (N))
3377 and then T1 = Universal_Real
3379 (not (Ada_Version >= Ada_05 and then Has_Fixed_Op (T1, Op_Id))
3380 or else Nkind (Parent (N)) = N_Type_Conversion)
3382 Add_One_Interp (N, Op_Id, Universal_Fixed);
3384 elsif Is_Numeric_Type (T1)
3385 and then Is_Numeric_Type (T2)
3386 and then (Covers (T1, T2) or else Covers (T2, T1))
3388 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3390 elsif Is_Fixed_Point_Type (T1)
3391 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3392 or else T2 = Universal_Integer)
3394 Add_One_Interp (N, Op_Id, T1);
3396 elsif T2 = Universal_Real
3397 and then Base_Type (T1) = Base_Type (Standard_Integer)
3398 and then Op_Name = Name_Op_Multiply
3400 Add_One_Interp (N, Op_Id, Any_Fixed);
3402 elsif T1 = Universal_Real
3403 and then Base_Type (T2) = Base_Type (Standard_Integer)
3405 Add_One_Interp (N, Op_Id, Any_Fixed);
3407 elsif Is_Fixed_Point_Type (T2)
3408 and then (Base_Type (T1) = Base_Type (Standard_Integer)
3409 or else T1 = Universal_Integer)
3410 and then Op_Name = Name_Op_Multiply
3412 Add_One_Interp (N, Op_Id, T2);
3414 elsif T1 = Universal_Real and then T2 = Universal_Integer then
3415 Add_One_Interp (N, Op_Id, T1);
3417 elsif T2 = Universal_Real
3418 and then T1 = Universal_Integer
3419 and then Op_Name = Name_Op_Multiply
3421 Add_One_Interp (N, Op_Id, T2);
3424 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
3426 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
3427 -- set does not require any special processing, since the Etype is
3428 -- already set (case of operation constructed by Exp_Fixed).
3430 if Is_Integer_Type (T1)
3431 and then (Covers (T1, T2) or else Covers (T2, T1))
3433 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
3436 elsif Op_Name = Name_Op_Expon then
3437 if Is_Numeric_Type (T1)
3438 and then not Is_Fixed_Point_Type (T1)
3439 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3440 or else T2 = Universal_Integer)
3442 Add_One_Interp (N, Op_Id, Base_Type (T1));
3445 else pragma Assert (Nkind (N) in N_Op_Shift);
3447 -- If not one of the predefined operators, the node may be one
3448 -- of the intrinsic functions. Its kind is always specific, and
3449 -- we can use it directly, rather than the name of the operation.
3451 if Is_Integer_Type (T1)
3452 and then (Base_Type (T2) = Base_Type (Standard_Integer)
3453 or else T2 = Universal_Integer)
3455 Add_One_Interp (N, Op_Id, Base_Type (T1));
3458 end Check_Arithmetic_Pair;
3460 -------------------------------
3461 -- Check_Misspelled_Selector --
3462 -------------------------------
3464 procedure Check_Misspelled_Selector
3465 (Prefix : Entity_Id;
3468 Max_Suggestions : constant := 2;
3469 Nr_Of_Suggestions : Natural := 0;
3471 Suggestion_1 : Entity_Id := Empty;
3472 Suggestion_2 : Entity_Id := Empty;
3477 -- All the components of the prefix of selector Sel are matched
3478 -- against Sel and a count is maintained of possible misspellings.
3479 -- When at the end of the analysis there are one or two (not more!)
3480 -- possible misspellings, these misspellings will be suggested as
3481 -- possible correction.
3483 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
3485 -- Concurrent types should be handled as well ???
3490 Get_Name_String (Chars (Sel));
3493 S : constant String (1 .. Name_Len) := Name_Buffer (1 .. Name_Len);
3496 Comp := First_Entity (Prefix);
3497 while Nr_Of_Suggestions <= Max_Suggestions
3498 and then Present (Comp)
3500 if Is_Visible_Component (Comp) then
3501 Get_Name_String (Chars (Comp));
3503 if Is_Bad_Spelling_Of (Name_Buffer (1 .. Name_Len), S) then
3504 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
3506 case Nr_Of_Suggestions is
3507 when 1 => Suggestion_1 := Comp;
3508 when 2 => Suggestion_2 := Comp;
3509 when others => exit;
3514 Comp := Next_Entity (Comp);
3517 -- Report at most two suggestions
3519 if Nr_Of_Suggestions = 1 then
3520 Error_Msg_NE ("\possible misspelling of&", Sel, Suggestion_1);
3522 elsif Nr_Of_Suggestions = 2 then
3523 Error_Msg_Node_2 := Suggestion_2;
3524 Error_Msg_NE ("\possible misspelling of& or&",
3528 end Check_Misspelled_Selector;
3530 ----------------------
3531 -- Defined_In_Scope --
3532 ----------------------
3534 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
3536 S1 : constant Entity_Id := Scope (Base_Type (T));
3539 or else (S1 = System_Aux_Id and then S = Scope (S1));
3540 end Defined_In_Scope;
3546 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
3553 Void_Interp_Seen : Boolean := False;
3556 if Ada_Version >= Ada_05 then
3557 Actual := First_Actual (N);
3558 while Present (Actual) loop
3560 -- Ada 2005 (AI-50217): Post an error in case of premature
3561 -- usage of an entity from the limited view.
3563 if not Analyzed (Etype (Actual))
3564 and then From_With_Type (Etype (Actual))
3566 Error_Msg_Qual_Level := 1;
3568 ("missing with_clause for scope of imported type&",
3569 Actual, Etype (Actual));
3570 Error_Msg_Qual_Level := 0;
3573 Next_Actual (Actual);
3577 -- Analyze each candidate call again, with full error reporting
3581 ("no candidate interpretations match the actuals:!", Nam);
3582 Err_Mode := All_Errors_Mode;
3583 All_Errors_Mode := True;
3585 -- If this is a call to an operation of a concurrent type,
3586 -- the failed interpretations have been removed from the
3587 -- name. Recover them to provide full diagnostics.
3589 if Nkind (Parent (Nam)) = N_Selected_Component then
3590 Set_Entity (Nam, Empty);
3591 New_Nam := New_Copy_Tree (Parent (Nam));
3592 Set_Is_Overloaded (New_Nam, False);
3593 Set_Is_Overloaded (Selector_Name (New_Nam), False);
3594 Set_Parent (New_Nam, Parent (Parent (Nam)));
3595 Analyze_Selected_Component (New_Nam);
3596 Get_First_Interp (Selector_Name (New_Nam), X, It);
3598 Get_First_Interp (Nam, X, It);
3601 while Present (It.Nam) loop
3602 if Etype (It.Nam) = Standard_Void_Type then
3603 Void_Interp_Seen := True;
3606 Analyze_One_Call (N, It.Nam, True, Success);
3607 Get_Next_Interp (X, It);
3610 if Nkind (N) = N_Function_Call then
3611 Get_First_Interp (Nam, X, It);
3612 while Present (It.Nam) loop
3613 if Ekind (It.Nam) = E_Function
3614 or else Ekind (It.Nam) = E_Operator
3618 Get_Next_Interp (X, It);
3622 -- If all interpretations are procedures, this deserves a
3623 -- more precise message. Ditto if this appears as the prefix
3624 -- of a selected component, which may be a lexical error.
3627 ("\context requires function call, found procedure name", Nam);
3629 if Nkind (Parent (N)) = N_Selected_Component
3630 and then N = Prefix (Parent (N))
3633 "\period should probably be semicolon", Parent (N));
3636 elsif Nkind (N) = N_Procedure_Call_Statement
3637 and then not Void_Interp_Seen
3640 "\function name found in procedure call", Nam);
3643 All_Errors_Mode := Err_Mode;
3646 ---------------------------
3647 -- Find_Arithmetic_Types --
3648 ---------------------------
3650 procedure Find_Arithmetic_Types
3655 Index1 : Interp_Index;
3656 Index2 : Interp_Index;
3660 procedure Check_Right_Argument (T : Entity_Id);
3661 -- Check right operand of operator
3663 --------------------------
3664 -- Check_Right_Argument --
3665 --------------------------
3667 procedure Check_Right_Argument (T : Entity_Id) is
3669 if not Is_Overloaded (R) then
3670 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
3672 Get_First_Interp (R, Index2, It2);
3673 while Present (It2.Typ) loop
3674 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
3675 Get_Next_Interp (Index2, It2);
3678 end Check_Right_Argument;
3680 -- Start processing for Find_Arithmetic_Types
3683 if not Is_Overloaded (L) then
3684 Check_Right_Argument (Etype (L));
3687 Get_First_Interp (L, Index1, It1);
3689 while Present (It1.Typ) loop
3690 Check_Right_Argument (It1.Typ);
3691 Get_Next_Interp (Index1, It1);
3695 end Find_Arithmetic_Types;
3697 ------------------------
3698 -- Find_Boolean_Types --
3699 ------------------------
3701 procedure Find_Boolean_Types
3706 Index : Interp_Index;
3709 procedure Check_Numeric_Argument (T : Entity_Id);
3710 -- Special case for logical operations one of whose operands is an
3711 -- integer literal. If both are literal the result is any modular type.
3713 ----------------------------
3714 -- Check_Numeric_Argument --
3715 ----------------------------
3717 procedure Check_Numeric_Argument (T : Entity_Id) is
3719 if T = Universal_Integer then
3720 Add_One_Interp (N, Op_Id, Any_Modular);
3722 elsif Is_Modular_Integer_Type (T) then
3723 Add_One_Interp (N, Op_Id, T);
3725 end Check_Numeric_Argument;
3727 -- Start of processing for Find_Boolean_Types
3730 if not Is_Overloaded (L) then
3731 if Etype (L) = Universal_Integer
3732 or else Etype (L) = Any_Modular
3734 if not Is_Overloaded (R) then
3735 Check_Numeric_Argument (Etype (R));
3738 Get_First_Interp (R, Index, It);
3739 while Present (It.Typ) loop
3740 Check_Numeric_Argument (It.Typ);
3741 Get_Next_Interp (Index, It);
3745 elsif Valid_Boolean_Arg (Etype (L))
3746 and then Has_Compatible_Type (R, Etype (L))
3748 Add_One_Interp (N, Op_Id, Etype (L));
3752 Get_First_Interp (L, Index, It);
3753 while Present (It.Typ) loop
3754 if Valid_Boolean_Arg (It.Typ)
3755 and then Has_Compatible_Type (R, It.Typ)
3757 Add_One_Interp (N, Op_Id, It.Typ);
3760 Get_Next_Interp (Index, It);
3763 end Find_Boolean_Types;
3765 ---------------------------
3766 -- Find_Comparison_Types --
3767 ---------------------------
3769 procedure Find_Comparison_Types
3774 Index : Interp_Index;
3776 Found : Boolean := False;
3779 Scop : Entity_Id := Empty;
3781 procedure Try_One_Interp (T1 : Entity_Id);
3782 -- Routine to try one proposed interpretation. Note that the context
3783 -- of the operator plays no role in resolving the arguments, so that
3784 -- if there is more than one interpretation of the operands that is
3785 -- compatible with comparison, the operation is ambiguous.
3787 --------------------
3788 -- Try_One_Interp --
3789 --------------------
3791 procedure Try_One_Interp (T1 : Entity_Id) is
3794 -- If the operator is an expanded name, then the type of the operand
3795 -- must be defined in the corresponding scope. If the type is
3796 -- universal, the context will impose the correct type.
3799 and then not Defined_In_Scope (T1, Scop)
3800 and then T1 /= Universal_Integer
3801 and then T1 /= Universal_Real
3802 and then T1 /= Any_String
3803 and then T1 /= Any_Composite
3808 if Valid_Comparison_Arg (T1)
3809 and then Has_Compatible_Type (R, T1)
3812 and then Base_Type (T1) /= Base_Type (T_F)
3814 It := Disambiguate (L, I_F, Index, Any_Type);
3816 if It = No_Interp then
3817 Ambiguous_Operands (N);
3818 Set_Etype (L, Any_Type);
3832 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
3837 -- Start processing for Find_Comparison_Types
3840 -- If left operand is aggregate, the right operand has to
3841 -- provide a usable type for it.
3843 if Nkind (L) = N_Aggregate
3844 and then Nkind (R) /= N_Aggregate
3846 Find_Comparison_Types (R, L, Op_Id, N);
3850 if Nkind (N) = N_Function_Call
3851 and then Nkind (Name (N)) = N_Expanded_Name
3853 Scop := Entity (Prefix (Name (N)));
3855 -- The prefix may be a package renaming, and the subsequent test
3856 -- requires the original package.
3858 if Ekind (Scop) = E_Package
3859 and then Present (Renamed_Entity (Scop))
3861 Scop := Renamed_Entity (Scop);
3862 Set_Entity (Prefix (Name (N)), Scop);
3866 if not Is_Overloaded (L) then
3867 Try_One_Interp (Etype (L));
3870 Get_First_Interp (L, Index, It);
3871 while Present (It.Typ) loop
3872 Try_One_Interp (It.Typ);
3873 Get_Next_Interp (Index, It);
3876 end Find_Comparison_Types;
3878 ----------------------------------------
3879 -- Find_Non_Universal_Interpretations --
3880 ----------------------------------------
3882 procedure Find_Non_Universal_Interpretations
3888 Index : Interp_Index;
3892 if T1 = Universal_Integer
3893 or else T1 = Universal_Real
3895 if not Is_Overloaded (R) then
3897 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
3899 Get_First_Interp (R, Index, It);
3900 while Present (It.Typ) loop
3901 if Covers (It.Typ, T1) then
3903 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
3906 Get_Next_Interp (Index, It);
3910 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
3912 end Find_Non_Universal_Interpretations;
3914 ------------------------------
3915 -- Find_Concatenation_Types --
3916 ------------------------------
3918 procedure Find_Concatenation_Types
3923 Op_Type : constant Entity_Id := Etype (Op_Id);
3926 if Is_Array_Type (Op_Type)
3927 and then not Is_Limited_Type (Op_Type)
3929 and then (Has_Compatible_Type (L, Op_Type)
3931 Has_Compatible_Type (L, Component_Type (Op_Type)))
3933 and then (Has_Compatible_Type (R, Op_Type)
3935 Has_Compatible_Type (R, Component_Type (Op_Type)))
3937 Add_One_Interp (N, Op_Id, Op_Type);
3939 end Find_Concatenation_Types;
3941 -------------------------
3942 -- Find_Equality_Types --
3943 -------------------------
3945 procedure Find_Equality_Types
3950 Index : Interp_Index;
3952 Found : Boolean := False;
3955 Scop : Entity_Id := Empty;
3957 procedure Try_One_Interp (T1 : Entity_Id);
3958 -- The context of the operator plays no role in resolving the
3959 -- arguments, so that if there is more than one interpretation
3960 -- of the operands that is compatible with equality, the construct
3961 -- is ambiguous and an error can be emitted now, after trying to
3962 -- disambiguate, i.e. applying preference rules.
3964 --------------------
3965 -- Try_One_Interp --
3966 --------------------
3968 procedure Try_One_Interp (T1 : Entity_Id) is
3970 -- If the operator is an expanded name, then the type of the operand
3971 -- must be defined in the corresponding scope. If the type is
3972 -- universal, the context will impose the correct type. An anonymous
3973 -- type for a 'Access reference is also universal in this sense, as
3974 -- the actual type is obtained from context.
3977 and then not Defined_In_Scope (T1, Scop)
3978 and then T1 /= Universal_Integer
3979 and then T1 /= Universal_Real
3980 and then T1 /= Any_Access
3981 and then T1 /= Any_String
3982 and then T1 /= Any_Composite
3983 and then (Ekind (T1) /= E_Access_Subprogram_Type
3984 or else Comes_From_Source (T1))
3989 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
3990 -- Do not allow anonymous access types in equality operators.
3992 if Ada_Version < Ada_05
3993 and then Ekind (T1) = E_Anonymous_Access_Type
3998 if T1 /= Standard_Void_Type
3999 and then not Is_Limited_Type (T1)
4000 and then not Is_Limited_Composite (T1)
4001 and then Has_Compatible_Type (R, T1)
4004 and then Base_Type (T1) /= Base_Type (T_F)
4006 It := Disambiguate (L, I_F, Index, Any_Type);
4008 if It = No_Interp then
4009 Ambiguous_Operands (N);
4010 Set_Etype (L, Any_Type);
4023 if not Analyzed (L) then
4027 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
4029 -- Case of operator was not visible, Etype still set to Any_Type
4031 if Etype (N) = Any_Type then
4037 -- Start of processing for Find_Equality_Types
4040 -- If left operand is aggregate, the right operand has to
4041 -- provide a usable type for it.
4043 if Nkind (L) = N_Aggregate
4044 and then Nkind (R) /= N_Aggregate
4046 Find_Equality_Types (R, L, Op_Id, N);
4050 if Nkind (N) = N_Function_Call
4051 and then Nkind (Name (N)) = N_Expanded_Name
4053 Scop := Entity (Prefix (Name (N)));
4055 -- The prefix may be a package renaming, and the subsequent test
4056 -- requires the original package.
4058 if Ekind (Scop) = E_Package
4059 and then Present (Renamed_Entity (Scop))
4061 Scop := Renamed_Entity (Scop);
4062 Set_Entity (Prefix (Name (N)), Scop);
4066 if not Is_Overloaded (L) then
4067 Try_One_Interp (Etype (L));
4070 Get_First_Interp (L, Index, It);
4071 while Present (It.Typ) loop
4072 Try_One_Interp (It.Typ);
4073 Get_Next_Interp (Index, It);
4076 end Find_Equality_Types;
4078 -------------------------
4079 -- Find_Negation_Types --
4080 -------------------------
4082 procedure Find_Negation_Types
4087 Index : Interp_Index;
4091 if not Is_Overloaded (R) then
4092 if Etype (R) = Universal_Integer then
4093 Add_One_Interp (N, Op_Id, Any_Modular);
4094 elsif Valid_Boolean_Arg (Etype (R)) then
4095 Add_One_Interp (N, Op_Id, Etype (R));
4099 Get_First_Interp (R, Index, It);
4100 while Present (It.Typ) loop
4101 if Valid_Boolean_Arg (It.Typ) then
4102 Add_One_Interp (N, Op_Id, It.Typ);
4105 Get_Next_Interp (Index, It);
4108 end Find_Negation_Types;
4110 ----------------------
4111 -- Find_Unary_Types --
4112 ----------------------
4114 procedure Find_Unary_Types
4119 Index : Interp_Index;
4123 if not Is_Overloaded (R) then
4124 if Is_Numeric_Type (Etype (R)) then
4125 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
4129 Get_First_Interp (R, Index, It);
4130 while Present (It.Typ) loop
4131 if Is_Numeric_Type (It.Typ) then
4132 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
4135 Get_Next_Interp (Index, It);
4138 end Find_Unary_Types;
4144 function Junk_Operand (N : Node_Id) return Boolean is
4148 if Error_Posted (N) then
4152 -- Get entity to be tested
4154 if Is_Entity_Name (N)
4155 and then Present (Entity (N))
4159 -- An odd case, a procedure name gets converted to a very peculiar
4160 -- function call, and here is where we detect this happening.
4162 elsif Nkind (N) = N_Function_Call
4163 and then Is_Entity_Name (Name (N))
4164 and then Present (Entity (Name (N)))
4168 -- Another odd case, there are at least some cases of selected
4169 -- components where the selected component is not marked as having
4170 -- an entity, even though the selector does have an entity
4172 elsif Nkind (N) = N_Selected_Component
4173 and then Present (Entity (Selector_Name (N)))
4175 Enode := Selector_Name (N);
4181 -- Now test the entity we got to see if it a bad case
4183 case Ekind (Entity (Enode)) is
4187 ("package name cannot be used as operand", Enode);
4189 when Generic_Unit_Kind =>
4191 ("generic unit name cannot be used as operand", Enode);
4195 ("subtype name cannot be used as operand", Enode);
4199 ("entry name cannot be used as operand", Enode);
4203 ("procedure name cannot be used as operand", Enode);
4207 ("exception name cannot be used as operand", Enode);
4209 when E_Block | E_Label | E_Loop =>
4211 ("label name cannot be used as operand", Enode);
4221 --------------------
4222 -- Operator_Check --
4223 --------------------
4225 procedure Operator_Check (N : Node_Id) is
4227 Remove_Abstract_Operations (N);
4229 -- Test for case of no interpretation found for operator
4231 if Etype (N) = Any_Type then
4237 R := Right_Opnd (N);
4239 if Nkind (N) in N_Binary_Op then
4245 -- If either operand has no type, then don't complain further,
4246 -- since this simply means that we have a propragated error.
4249 or else Etype (R) = Any_Type
4250 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
4254 -- We explicitly check for the case of concatenation of component
4255 -- with component to avoid reporting spurious matching array types
4256 -- that might happen to be lurking in distant packages (such as
4257 -- run-time packages). This also prevents inconsistencies in the
4258 -- messages for certain ACVC B tests, which can vary depending on
4259 -- types declared in run-time interfaces. Another improvement when
4260 -- aggregates are present is to look for a well-typed operand.
4262 elsif Present (Candidate_Type)
4263 and then (Nkind (N) /= N_Op_Concat
4264 or else Is_Array_Type (Etype (L))
4265 or else Is_Array_Type (Etype (R)))
4268 if Nkind (N) = N_Op_Concat then
4269 if Etype (L) /= Any_Composite
4270 and then Is_Array_Type (Etype (L))
4272 Candidate_Type := Etype (L);
4274 elsif Etype (R) /= Any_Composite
4275 and then Is_Array_Type (Etype (R))
4277 Candidate_Type := Etype (R);
4282 ("operator for} is not directly visible!",
4283 N, First_Subtype (Candidate_Type));
4284 Error_Msg_N ("use clause would make operation legal!", N);
4287 -- If either operand is a junk operand (e.g. package name), then
4288 -- post appropriate error messages, but do not complain further.
4290 -- Note that the use of OR in this test instead of OR ELSE
4291 -- is quite deliberate, we may as well check both operands
4292 -- in the binary operator case.
4294 elsif Junk_Operand (R)
4295 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
4299 -- If we have a logical operator, one of whose operands is
4300 -- Boolean, then we know that the other operand cannot resolve
4301 -- to Boolean (since we got no interpretations), but in that
4302 -- case we pretty much know that the other operand should be
4303 -- Boolean, so resolve it that way (generating an error)
4305 elsif Nkind (N) = N_Op_And
4309 Nkind (N) = N_Op_Xor
4311 if Etype (L) = Standard_Boolean then
4312 Resolve (R, Standard_Boolean);
4314 elsif Etype (R) = Standard_Boolean then
4315 Resolve (L, Standard_Boolean);
4319 -- For an arithmetic operator or comparison operator, if one
4320 -- of the operands is numeric, then we know the other operand
4321 -- is not the same numeric type. If it is a non-numeric type,
4322 -- then probably it is intended to match the other operand.
4324 elsif Nkind (N) = N_Op_Add or else
4325 Nkind (N) = N_Op_Divide or else
4326 Nkind (N) = N_Op_Ge or else
4327 Nkind (N) = N_Op_Gt or else
4328 Nkind (N) = N_Op_Le or else
4329 Nkind (N) = N_Op_Lt or else
4330 Nkind (N) = N_Op_Mod or else
4331 Nkind (N) = N_Op_Multiply or else
4332 Nkind (N) = N_Op_Rem or else
4333 Nkind (N) = N_Op_Subtract
4335 if Is_Numeric_Type (Etype (L))
4336 and then not Is_Numeric_Type (Etype (R))
4338 Resolve (R, Etype (L));
4341 elsif Is_Numeric_Type (Etype (R))
4342 and then not Is_Numeric_Type (Etype (L))
4344 Resolve (L, Etype (R));
4348 -- Comparisons on A'Access are common enough to deserve a
4351 elsif (Nkind (N) = N_Op_Eq or else
4352 Nkind (N) = N_Op_Ne)
4353 and then Ekind (Etype (L)) = E_Access_Attribute_Type
4354 and then Ekind (Etype (R)) = E_Access_Attribute_Type
4357 ("two access attributes cannot be compared directly", N);
4359 ("\they must be converted to an explicit type for comparison",
4363 -- Another one for C programmers
4365 elsif Nkind (N) = N_Op_Concat
4366 and then Valid_Boolean_Arg (Etype (L))
4367 and then Valid_Boolean_Arg (Etype (R))
4369 Error_Msg_N ("invalid operands for concatenation", N);
4370 Error_Msg_N ("\maybe AND was meant", N);
4373 -- A special case for comparison of access parameter with null
4375 elsif Nkind (N) = N_Op_Eq
4376 and then Is_Entity_Name (L)
4377 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
4378 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
4380 and then Nkind (R) = N_Null
4382 Error_Msg_N ("access parameter is not allowed to be null", L);
4383 Error_Msg_N ("\(call would raise Constraint_Error)", L);
4387 -- If we fall through then just give general message. Note
4388 -- that in the following messages, if the operand is overloaded
4389 -- we choose an arbitrary type to complain about, but that is
4390 -- probably more useful than not giving a type at all.
4392 if Nkind (N) in N_Unary_Op then
4393 Error_Msg_Node_2 := Etype (R);
4394 Error_Msg_N ("operator& not defined for}", N);
4398 if Nkind (N) in N_Binary_Op then
4399 if not Is_Overloaded (L)
4400 and then not Is_Overloaded (R)
4401 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
4403 Error_Msg_Node_2 := Etype (R);
4404 Error_Msg_N ("there is no applicable operator& for}", N);
4407 Error_Msg_N ("invalid operand types for operator&", N);
4409 if Nkind (N) /= N_Op_Concat then
4410 Error_Msg_NE ("\left operand has}!", N, Etype (L));
4411 Error_Msg_NE ("\right operand has}!", N, Etype (R));
4420 -----------------------------------------
4421 -- Process_Implicit_Dereference_Prefix --
4422 -----------------------------------------
4424 procedure Process_Implicit_Dereference_Prefix
4431 if Operating_Mode = Check_Semantics and then Present (E) then
4433 -- We create a dummy reference to E to ensure that the reference
4434 -- is not considered as part of an assignment (an implicit
4435 -- dereference can never assign to its prefix). The Comes_From_Source
4436 -- attribute needs to be propagated for accurate warnings.
4438 Ref := New_Reference_To (E, Sloc (P));
4439 Set_Comes_From_Source (Ref, Comes_From_Source (P));
4440 Generate_Reference (E, Ref);
4442 end Process_Implicit_Dereference_Prefix;
4444 --------------------------------
4445 -- Remove_Abstract_Operations --
4446 --------------------------------
4448 procedure Remove_Abstract_Operations (N : Node_Id) is
4451 Abstract_Op : Entity_Id := Empty;
4453 -- AI-310: If overloaded, remove abstract non-dispatching
4454 -- operations. We activate this if either extensions are
4455 -- enabled, or if the abstract operation in question comes
4456 -- from a predefined file. This latter test allows us to
4457 -- use abstract to make operations invisible to users. In
4458 -- particular, if type Address is non-private and abstract
4459 -- subprograms are used to hide its operators, they will be
4462 type Operand_Position is (First_Op, Second_Op);
4463 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
4465 procedure Remove_Address_Interpretations (Op : Operand_Position);
4466 -- Ambiguities may arise when the operands are literal and the
4467 -- address operations in s-auxdec are visible. In that case, remove
4468 -- the interpretation of a literal as Address, to retain the semantics
4469 -- of Address as a private type.
4471 ------------------------------------
4472 -- Remove_Address_Interpretations --
4473 ------------------------------------
4475 procedure Remove_Address_Interpretations (Op : Operand_Position) is
4479 if Is_Overloaded (N) then
4480 Get_First_Interp (N, I, It);
4481 while Present (It.Nam) loop
4482 Formal := First_Entity (It.Nam);
4484 if Op = Second_Op then
4485 Formal := Next_Entity (Formal);
4488 if Is_Descendent_Of_Address (Etype (Formal)) then
4492 Get_Next_Interp (I, It);
4495 end Remove_Address_Interpretations;
4497 -- Start of processing for Remove_Abstract_Operations
4500 if Is_Overloaded (N) then
4501 Get_First_Interp (N, I, It);
4503 while Present (It.Nam) loop
4504 if not Is_Type (It.Nam)
4505 and then Is_Abstract (It.Nam)
4506 and then not Is_Dispatching_Operation (It.Nam)
4508 (Ada_Version >= Ada_05
4509 or else Is_Predefined_File_Name
4510 (Unit_File_Name (Get_Source_Unit (It.Nam))))
4513 Abstract_Op := It.Nam;
4518 Get_Next_Interp (I, It);
4521 if No (Abstract_Op) then
4524 elsif Nkind (N) in N_Op then
4526 -- Remove interpretations that treat literals as addresses.
4527 -- This is never appropriate.
4529 if Nkind (N) in N_Binary_Op then
4531 U1 : constant Boolean :=
4532 Present (Universal_Interpretation (Right_Opnd (N)));
4533 U2 : constant Boolean :=
4534 Present (Universal_Interpretation (Left_Opnd (N)));
4537 if U1 and then not U2 then
4538 Remove_Address_Interpretations (Second_Op);
4540 elsif U2 and then not U1 then
4541 Remove_Address_Interpretations (First_Op);
4544 if not (U1 and U2) then
4546 -- Remove corresponding predefined operator, which is
4547 -- always added to the overload set.
4549 Get_First_Interp (N, I, It);
4550 while Present (It.Nam) loop
4551 if Scope (It.Nam) = Standard_Standard
4552 and then Base_Type (It.Typ) =
4553 Base_Type (Etype (Abstract_Op))
4558 Get_Next_Interp (I, It);
4561 elsif Is_Overloaded (N)
4562 and then Present (Univ_Type)
4564 -- If both operands have a universal interpretation,
4565 -- select the predefined operator and discard others.
4567 Get_First_Interp (N, I, It);
4569 while Present (It.Nam) loop
4570 if Scope (It.Nam) = Standard_Standard then
4571 Set_Etype (N, Univ_Type);
4572 Set_Entity (N, It.Nam);
4573 Set_Is_Overloaded (N, False);
4577 Get_Next_Interp (I, It);
4583 elsif Nkind (N) = N_Function_Call
4585 (Nkind (Name (N)) = N_Operator_Symbol
4587 (Nkind (Name (N)) = N_Expanded_Name
4589 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
4593 Arg1 : constant Node_Id := First (Parameter_Associations (N));
4594 U1 : constant Boolean :=
4595 Present (Universal_Interpretation (Arg1));
4596 U2 : constant Boolean :=
4597 Present (Next (Arg1)) and then
4598 Present (Universal_Interpretation (Next (Arg1)));
4601 if U1 and then not U2 then
4602 Remove_Address_Interpretations (First_Op);
4604 elsif U2 and then not U1 then
4605 Remove_Address_Interpretations (Second_Op);
4608 if not (U1 and U2) then
4609 Get_First_Interp (N, I, It);
4610 while Present (It.Nam) loop
4611 if Scope (It.Nam) = Standard_Standard
4612 and then It.Typ = Base_Type (Etype (Abstract_Op))
4617 Get_Next_Interp (I, It);
4623 -- If the removal has left no valid interpretations, emit
4624 -- error message now and label node as illegal.
4626 if Present (Abstract_Op) then
4627 Get_First_Interp (N, I, It);
4631 -- Removal of abstract operation left no viable candidate
4633 Set_Etype (N, Any_Type);
4634 Error_Msg_Sloc := Sloc (Abstract_Op);
4636 ("cannot call abstract operation& declared#", N, Abstract_Op);
4640 end Remove_Abstract_Operations;
4642 -----------------------
4643 -- Try_Indirect_Call --
4644 -----------------------
4646 function Try_Indirect_Call
4649 Typ : Entity_Id) return Boolean
4656 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
4657 Actual := First_Actual (N);
4658 Formal := First_Formal (Designated_Type (Typ));
4660 while Present (Actual)
4661 and then Present (Formal)
4663 if not Has_Compatible_Type (Actual, Etype (Formal)) then
4668 Next_Formal (Formal);
4671 if No (Actual) and then No (Formal) then
4672 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
4674 -- Nam is a candidate interpretation for the name in the call,
4675 -- if it is not an indirect call.
4677 if not Is_Type (Nam)
4678 and then Is_Entity_Name (Name (N))
4680 Set_Entity (Name (N), Nam);
4687 end Try_Indirect_Call;
4689 ----------------------
4690 -- Try_Indexed_Call --
4691 ----------------------
4693 function Try_Indexed_Call
4696 Typ : Entity_Id) return Boolean
4698 Actuals : constant List_Id := Parameter_Associations (N);
4703 Actual := First (Actuals);
4704 Index := First_Index (Typ);
4705 while Present (Actual)
4706 and then Present (Index)
4708 -- If the parameter list has a named association, the expression
4709 -- is definitely a call and not an indexed component.
4711 if Nkind (Actual) = N_Parameter_Association then
4715 if not Has_Compatible_Type (Actual, Etype (Index)) then
4723 if No (Actual) and then No (Index) then
4724 Add_One_Interp (N, Nam, Component_Type (Typ));
4726 -- Nam is a candidate interpretation for the name in the call,
4727 -- if it is not an indirect call.
4729 if not Is_Type (Nam)
4730 and then Is_Entity_Name (Name (N))
4732 Set_Entity (Name (N), Nam);
4739 end Try_Indexed_Call;
4741 --------------------------
4742 -- Try_Object_Operation --
4743 --------------------------
4745 function Try_Object_Operation (N : Node_Id) return Boolean is
4746 K : constant Node_Kind := Nkind (Parent (N));
4747 Loc : constant Source_Ptr := Sloc (N);
4748 Is_Subprg_Call : constant Boolean := K = N_Procedure_Call_Statement
4749 or else K = N_Function_Call;
4750 Obj : constant Node_Id := Prefix (N);
4751 Subprog : constant Node_Id := Selector_Name (N);
4754 Call_Node : Node_Id;
4755 Call_Node_Case : Node_Id := Empty;
4756 First_Actual : Node_Id;
4757 Node_To_Replace : Node_Id;
4758 Obj_Type : Entity_Id := Etype (Obj);
4760 procedure Complete_Object_Operation
4761 (Call_Node : Node_Id;
4762 Node_To_Replace : Node_Id;
4764 -- Set Subprog as the name of Call_Node, replace Node_To_Replace with
4765 -- Call_Node and reanalyze Node_To_Replace.
4767 procedure Transform_Object_Operation
4768 (Call_Node : out Node_Id;
4769 First_Actual : Node_Id;
4770 Node_To_Replace : out Node_Id;
4772 -- Transform Object.Operation (...) to Operation (Object, ...)
4773 -- Call_Node is the resulting subprogram call node, First_Actual is
4774 -- either the object Obj or an explicit dereference of Obj in certain
4775 -- cases, Node_To_Replace is either N or the parent of N, and Subprog
4776 -- is the subprogram we are trying to match.
4778 function Try_Class_Wide_Operation
4779 (Call_Node : Node_Id;
4780 Node_To_Replace : Node_Id) return Boolean;
4781 -- Traverse all the ancestor types looking for a class-wide subprogram
4782 -- that matches Subprog.
4784 function Try_Primitive_Operation
4785 (Call_Node : Node_Id;
4786 Node_To_Replace : Node_Id) return Boolean;
4787 -- Traverse the list of primitive subprograms looking for a subprogram
4788 -- than matches Subprog.
4790 -------------------------------
4791 -- Complete_Object_Operation --
4792 -------------------------------
4794 procedure Complete_Object_Operation
4795 (Call_Node : Node_Id;
4796 Node_To_Replace : Node_Id;
4800 Set_Name (Call_Node, New_Copy_Tree (Subprog));
4801 Set_Analyzed (Call_Node, False);
4802 Replace (Node_To_Replace, Call_Node);
4803 Analyze (Node_To_Replace);
4805 end Complete_Object_Operation;
4807 --------------------------------
4808 -- Transform_Object_Operation --
4809 --------------------------------
4811 procedure Transform_Object_Operation
4812 (Call_Node : out Node_Id;
4813 First_Actual : Node_Id;
4814 Node_To_Replace : out Node_Id;
4818 Parent_Node : constant Node_Id := Parent (N);
4821 Actuals := New_List (New_Copy_Tree (First_Actual));
4823 if (Nkind (Parent_Node) = N_Function_Call
4825 Nkind (Parent_Node) = N_Procedure_Call_Statement)
4827 -- Avoid recursive calls
4829 and then N /= First (Parameter_Associations (Parent_Node))
4831 Node_To_Replace := Parent_Node;
4833 Append_List_To (Actuals,
4834 New_Copy_List (Parameter_Associations (Parent_Node)));
4836 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
4838 Make_Procedure_Call_Statement (Loc,
4839 Name => New_Copy_Tree (Subprog),
4840 Parameter_Associations => Actuals);
4843 pragma Assert (Nkind (Parent_Node) = N_Function_Call);
4846 Make_Function_Call (Loc,
4847 Name => New_Copy_Tree (Subprog),
4848 Parameter_Associations => Actuals);
4852 -- Parameterless call
4855 Node_To_Replace := N;
4858 Make_Function_Call (Loc,
4859 Name => New_Copy_Tree (Subprog),
4860 Parameter_Associations => Actuals);
4863 end Transform_Object_Operation;
4865 ------------------------------
4866 -- Try_Class_Wide_Operation --
4867 ------------------------------
4869 function Try_Class_Wide_Operation
4870 (Call_Node : Node_Id;
4871 Node_To_Replace : Node_Id) return Boolean
4873 Anc_Type : Entity_Id;
4880 -- Loop through ancestor types, traverse their homonym chains and
4881 -- gather all interpretations of the subprogram.
4883 Anc_Type := Obj_Type;
4885 Hom := Current_Entity (Subprog);
4886 while Present (Hom) loop
4887 if (Ekind (Hom) = E_Procedure
4889 Ekind (Hom) = E_Function)
4890 and then Present (First_Formal (Hom))
4891 and then Etype (First_Formal (Hom)) =
4892 Class_Wide_Type (Anc_Type)
4894 Hom_Ref := New_Reference_To (Hom, Loc);
4896 -- When both the type of the object and the type of the
4897 -- first formal of the primitive operation are tagged
4898 -- access types, we use a node with the object as first
4901 if Is_Access_Type (Etype (Obj))
4902 and then Ekind (Etype (First_Formal (Hom))) =
4903 E_Anonymous_Access_Type
4905 -- Allocate the node only once
4907 if not Present (Call_Node_Case) then
4908 Transform_Object_Operation (
4909 Call_Node => Call_Node_Case,
4910 First_Actual => Obj,
4911 Node_To_Replace => Dummy,
4912 Subprog => Subprog);
4914 Set_Etype (Call_Node_Case, Any_Type);
4915 Set_Parent (Call_Node_Case, Parent (Node_To_Replace));
4918 Set_Name (Call_Node_Case, Hom_Ref);
4921 N => Call_Node_Case,
4924 Success => Success);
4927 Complete_Object_Operation (
4928 Call_Node => Call_Node_Case,
4929 Node_To_Replace => Node_To_Replace,
4930 Subprog => Hom_Ref);
4935 -- ??? comment required
4938 Set_Name (Call_Node, Hom_Ref);
4944 Success => Success);
4947 Complete_Object_Operation (
4948 Call_Node => Call_Node,
4949 Node_To_Replace => Node_To_Replace,
4950 Subprog => Hom_Ref);
4957 Hom := Homonym (Hom);
4960 -- Climb to ancestor type if there is one
4962 exit when Etype (Anc_Type) = Anc_Type;
4963 Anc_Type := Etype (Anc_Type);
4967 end Try_Class_Wide_Operation;
4969 -----------------------------
4970 -- Try_Primitive_Operation --
4971 -----------------------------
4973 function Try_Primitive_Operation
4974 (Call_Node : Node_Id;
4975 Node_To_Replace : Node_Id) return Boolean
4979 Prim_Op : Entity_Id;
4980 Prim_Op_Ref : Node_Id;
4984 -- Look for the subprogram in the list of primitive operations
4986 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
4987 while Present (Elmt) loop
4988 Prim_Op := Node (Elmt);
4990 if Chars (Prim_Op) = Chars (Subprog)
4991 and then Present (First_Formal (Prim_Op))
4993 Prim_Op_Ref := New_Reference_To (Prim_Op, Loc);
4995 -- When both the type of the object and the type of the first
4996 -- formal of the primitive operation are tagged access types,
4997 -- we use a node with the object as first actual.
4999 if Is_Access_Type (Etype (Obj))
5000 and then Ekind (Etype (First_Formal (Prim_Op))) =
5001 E_Anonymous_Access_Type
5003 -- Allocate the node only once
5005 if not Present (Call_Node_Case) then
5006 Transform_Object_Operation (
5007 Call_Node => Call_Node_Case,
5008 First_Actual => Obj,
5009 Node_To_Replace => Dummy,
5010 Subprog => Subprog);
5012 Set_Etype (Call_Node_Case, Any_Type);
5013 Set_Parent (Call_Node_Case, Parent (Node_To_Replace));
5016 Set_Name (Call_Node_Case, Prim_Op_Ref);
5019 N => Call_Node_Case,
5022 Success => Success);
5025 Complete_Object_Operation (
5026 Call_Node => Call_Node_Case,
5027 Node_To_Replace => Node_To_Replace,
5028 Subprog => Prim_Op_Ref);
5033 -- Comment required ???
5036 Set_Name (Call_Node, Prim_Op_Ref);
5042 Success => Success);
5045 Complete_Object_Operation (
5046 Call_Node => Call_Node,
5047 Node_To_Replace => Node_To_Replace,
5048 Subprog => Prim_Op_Ref);
5059 end Try_Primitive_Operation;
5061 -- Start of processing for Try_Object_Operation
5064 if Is_Access_Type (Obj_Type) then
5065 Obj_Type := Designated_Type (Obj_Type);
5068 if Ekind (Obj_Type) = E_Private_Subtype then
5069 Obj_Type := Base_Type (Obj_Type);
5072 if Is_Class_Wide_Type (Obj_Type) then
5073 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
5076 -- Analyze the actuals in case of subprogram call
5078 if Is_Subprg_Call and then N = Name (Parent (N)) then
5079 Actual := First (Parameter_Associations (Parent (N)));
5080 while Present (Actual) loop
5082 Check_Parameterless_Call (Actual);
5087 -- If the object is of an Access type, explicit dereference is
5090 if Is_Access_Type (Etype (Obj)) then
5092 Make_Explicit_Dereference (Sloc (Obj), Obj);
5093 Set_Etype (First_Actual, Obj_Type);
5095 First_Actual := Obj;
5098 -- Build a subprogram call node
5100 Transform_Object_Operation (
5101 Call_Node => Call_Node,
5102 First_Actual => First_Actual,
5103 Node_To_Replace => Node_To_Replace,
5104 Subprog => Subprog);
5106 Set_Etype (Call_Node, Any_Type);
5107 Set_Parent (Call_Node, Parent (Node_To_Replace));
5110 Try_Primitive_Operation
5111 (Call_Node => Call_Node,
5112 Node_To_Replace => Node_To_Replace)
5114 Try_Class_Wide_Operation
5115 (Call_Node => Call_Node,
5116 Node_To_Replace => Node_To_Replace);
5117 end Try_Object_Operation;