1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Debug; use Debug;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_Util; use Exp_Util;
32 with Fname; use Fname;
33 with Itypes; use Itypes;
35 with Lib.Xref; use Lib.Xref;
36 with Namet; use Namet;
37 with Namet.Sp; use Namet.Sp;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Output; use Output;
42 with Restrict; use Restrict;
43 with Rident; use Rident;
45 with Sem_Aux; use Sem_Aux;
46 with Sem_Case; use Sem_Case;
47 with Sem_Cat; use Sem_Cat;
48 with Sem_Ch3; use Sem_Ch3;
49 with Sem_Ch5; use Sem_Ch5;
50 with Sem_Ch6; use Sem_Ch6;
51 with Sem_Ch8; use Sem_Ch8;
52 with Sem_Disp; use Sem_Disp;
53 with Sem_Dist; use Sem_Dist;
54 with Sem_Eval; use Sem_Eval;
55 with Sem_Res; use Sem_Res;
56 with Sem_Type; use Sem_Type;
57 with Sem_Util; use Sem_Util;
58 with Sem_Warn; use Sem_Warn;
59 with Stand; use Stand;
60 with Sinfo; use Sinfo;
61 with Snames; use Snames;
62 with Tbuild; use Tbuild;
64 package body Sem_Ch4 is
66 -----------------------
67 -- Local Subprograms --
68 -----------------------
70 procedure Analyze_Concatenation_Rest (N : Node_Id);
71 -- Does the "rest" of the work of Analyze_Concatenation, after the left
72 -- operand has been analyzed. See Analyze_Concatenation for details.
74 procedure Analyze_Expression (N : Node_Id);
75 -- For expressions that are not names, this is just a call to analyze.
76 -- If the expression is a name, it may be a call to a parameterless
77 -- function, and if so must be converted into an explicit call node
78 -- and analyzed as such. This deproceduring must be done during the first
79 -- pass of overload resolution, because otherwise a procedure call with
80 -- overloaded actuals may fail to resolve.
82 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id);
83 -- Analyze a call of the form "+"(x, y), etc. The prefix of the call
84 -- is an operator name or an expanded name whose selector is an operator
85 -- name, and one possible interpretation is as a predefined operator.
87 procedure Analyze_Overloaded_Selected_Component (N : Node_Id);
88 -- If the prefix of a selected_component is overloaded, the proper
89 -- interpretation that yields a record type with the proper selector
90 -- name must be selected.
92 procedure Analyze_User_Defined_Binary_Op (N : Node_Id; Op_Id : Entity_Id);
93 -- Procedure to analyze a user defined binary operator, which is resolved
94 -- like a function, but instead of a list of actuals it is presented
95 -- with the left and right operands of an operator node.
97 procedure Analyze_User_Defined_Unary_Op (N : Node_Id; Op_Id : Entity_Id);
98 -- Procedure to analyze a user defined unary operator, which is resolved
99 -- like a function, but instead of a list of actuals, it is presented with
100 -- the operand of the operator node.
102 procedure Ambiguous_Operands (N : Node_Id);
103 -- For equality, membership, and comparison operators with overloaded
104 -- arguments, list possible interpretations.
106 procedure Analyze_One_Call
110 Success : out Boolean;
111 Skip_First : Boolean := False);
112 -- Check one interpretation of an overloaded subprogram name for
113 -- compatibility with the types of the actuals in a call. If there is a
114 -- single interpretation which does not match, post error if Report is
117 -- Nam is the entity that provides the formals against which the actuals
118 -- are checked. Nam is either the name of a subprogram, or the internal
119 -- subprogram type constructed for an access_to_subprogram. If the actuals
120 -- are compatible with Nam, then Nam is added to the list of candidate
121 -- interpretations for N, and Success is set to True.
123 -- The flag Skip_First is used when analyzing a call that was rewritten
124 -- from object notation. In this case the first actual may have to receive
125 -- an explicit dereference, depending on the first formal of the operation
126 -- being called. The caller will have verified that the object is legal
127 -- for the call. If the remaining parameters match, the first parameter
128 -- will rewritten as a dereference if needed, prior to completing analysis.
130 procedure Check_Misspelled_Selector
133 -- Give possible misspelling diagnostic if Sel is likely to be a mis-
134 -- spelling of one of the selectors of the Prefix. This is called by
135 -- Analyze_Selected_Component after producing an invalid selector error
138 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean;
139 -- Verify that type T is declared in scope S. Used to find interpretations
140 -- for operators given by expanded names. This is abstracted as a separate
141 -- function to handle extensions to System, where S is System, but T is
142 -- declared in the extension.
144 procedure Find_Arithmetic_Types
148 -- L and R are the operands of an arithmetic operator. Find
149 -- consistent pairs of interpretations for L and R that have a
150 -- numeric type consistent with the semantics of the operator.
152 procedure Find_Comparison_Types
156 -- L and R are operands of a comparison operator. Find consistent
157 -- pairs of interpretations for L and R.
159 procedure Find_Concatenation_Types
163 -- For the four varieties of concatenation
165 procedure Find_Equality_Types
169 -- Ditto for equality operators
171 procedure Find_Boolean_Types
175 -- Ditto for binary logical operations
177 procedure Find_Negation_Types
181 -- Find consistent interpretation for operand of negation operator
183 procedure Find_Non_Universal_Interpretations
188 -- For equality and comparison operators, the result is always boolean,
189 -- and the legality of the operation is determined from the visibility
190 -- of the operand types. If one of the operands has a universal interpre-
191 -- tation, the legality check uses some compatible non-universal
192 -- interpretation of the other operand. N can be an operator node, or
193 -- a function call whose name is an operator designator.
195 function Find_Primitive_Operation (N : Node_Id) return Boolean;
196 -- Find candidate interpretations for the name Obj.Proc when it appears
197 -- in a subprogram renaming declaration.
199 procedure Find_Unary_Types
203 -- Unary arithmetic types: plus, minus, abs
205 procedure Check_Arithmetic_Pair
209 -- Subsidiary procedure to Find_Arithmetic_Types. T1 and T2 are valid
210 -- types for left and right operand. Determine whether they constitute
211 -- a valid pair for the given operator, and record the corresponding
212 -- interpretation of the operator node. The node N may be an operator
213 -- node (the usual case) or a function call whose prefix is an operator
214 -- designator. In both cases Op_Id is the operator name itself.
216 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id);
217 -- Give detailed information on overloaded call where none of the
218 -- interpretations match. N is the call node, Nam the designator for
219 -- the overloaded entity being called.
221 function Junk_Operand (N : Node_Id) return Boolean;
222 -- Test for an operand that is an inappropriate entity (e.g. a package
223 -- name or a label). If so, issue an error message and return True. If
224 -- the operand is not an inappropriate entity kind, return False.
226 procedure Operator_Check (N : Node_Id);
227 -- Verify that an operator has received some valid interpretation. If none
228 -- was found, determine whether a use clause would make the operation
229 -- legal. The variable Candidate_Type (defined in Sem_Type) is set for
230 -- every type compatible with the operator, even if the operator for the
231 -- type is not directly visible. The routine uses this type to emit a more
232 -- informative message.
234 function Process_Implicit_Dereference_Prefix
236 P : Node_Id) return Entity_Id;
237 -- Called when P is the prefix of an implicit dereference, denoting an
238 -- object E. The function returns the designated type of the prefix, taking
239 -- into account that the designated type of an anonymous access type may be
240 -- a limited view, when the non-limited view is visible.
241 -- If in semantics only mode (-gnatc or generic), the function also records
242 -- that the prefix is a reference to E, if any. Normally, such a reference
243 -- is generated only when the implicit dereference is expanded into an
244 -- explicit one, but for consistency we must generate the reference when
245 -- expansion is disabled as well.
247 procedure Remove_Abstract_Operations (N : Node_Id);
248 -- Ada 2005: implementation of AI-310. An abstract non-dispatching
249 -- operation is not a candidate interpretation.
251 function Try_Indexed_Call
255 Skip_First : Boolean) return Boolean;
256 -- If a function has defaults for all its actuals, a call to it may in fact
257 -- be an indexing on the result of the call. Try_Indexed_Call attempts the
258 -- interpretation as an indexing, prior to analysis as a call. If both are
259 -- possible, the node is overloaded with both interpretations (same symbol
260 -- but two different types). If the call is written in prefix form, the
261 -- prefix becomes the first parameter in the call, and only the remaining
262 -- actuals must be checked for the presence of defaults.
264 function Try_Indirect_Call
267 Typ : Entity_Id) return Boolean;
268 -- Similarly, a function F that needs no actuals can return an access to a
269 -- subprogram, and the call F (X) interpreted as F.all (X). In this case
270 -- the call may be overloaded with both interpretations.
272 function Try_Object_Operation (N : Node_Id) return Boolean;
273 -- Ada 2005 (AI-252): Support the object.operation notation. If node N
274 -- is a call in this notation, it is transformed into a normal subprogram
275 -- call where the prefix is a parameter, and True is returned. If node
276 -- N is not of this form, it is unchanged, and False is returned.
278 procedure wpo (T : Entity_Id);
279 pragma Warnings (Off, wpo);
280 -- Used for debugging: obtain list of primitive operations even if
281 -- type is not frozen and dispatch table is not built yet.
283 ------------------------
284 -- Ambiguous_Operands --
285 ------------------------
287 procedure Ambiguous_Operands (N : Node_Id) is
288 procedure List_Operand_Interps (Opnd : Node_Id);
290 --------------------------
291 -- List_Operand_Interps --
292 --------------------------
294 procedure List_Operand_Interps (Opnd : Node_Id) is
299 if Is_Overloaded (Opnd) then
300 if Nkind (Opnd) in N_Op then
302 elsif Nkind (Opnd) = N_Function_Call then
312 if Opnd = Left_Opnd (N) then
313 Error_Msg_N ("\left operand has the following interpretations", N);
316 ("\right operand has the following interpretations", N);
320 List_Interps (Nam, Err);
321 end List_Operand_Interps;
323 -- Start of processing for Ambiguous_Operands
326 if Nkind (N) in N_Membership_Test then
327 Error_Msg_N ("ambiguous operands for membership", N);
329 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne) then
330 Error_Msg_N ("ambiguous operands for equality", N);
333 Error_Msg_N ("ambiguous operands for comparison", N);
336 if All_Errors_Mode then
337 List_Operand_Interps (Left_Opnd (N));
338 List_Operand_Interps (Right_Opnd (N));
340 Error_Msg_N ("\use -gnatf switch for details", N);
342 end Ambiguous_Operands;
344 -----------------------
345 -- Analyze_Aggregate --
346 -----------------------
348 -- Most of the analysis of Aggregates requires that the type be known,
349 -- and is therefore put off until resolution.
351 procedure Analyze_Aggregate (N : Node_Id) is
353 if No (Etype (N)) then
354 Set_Etype (N, Any_Composite);
356 end Analyze_Aggregate;
358 -----------------------
359 -- Analyze_Allocator --
360 -----------------------
362 procedure Analyze_Allocator (N : Node_Id) is
363 Loc : constant Source_Ptr := Sloc (N);
364 Sav_Errs : constant Nat := Serious_Errors_Detected;
365 E : Node_Id := Expression (N);
366 Acc_Type : Entity_Id;
372 -- Deal with allocator restrictions
374 -- In accordance with H.4(7), the No_Allocators restriction only applies
375 -- to user-written allocators. The same consideration applies to the
376 -- No_Allocators_Before_Elaboration restriction.
378 if Comes_From_Source (N) then
379 Check_Restriction (No_Allocators, N);
381 -- Processing for No_Allocators_After_Elaboration, loop to look at
382 -- enclosing context, checking task case and main subprogram case.
386 while Present (P) loop
388 -- In both cases we need a handled sequence of statements, where
389 -- the occurrence of the allocator is within the statements.
391 if Nkind (P) = N_Handled_Sequence_Of_Statements
392 and then Is_List_Member (C)
393 and then List_Containing (C) = Statements (P)
395 -- Check for allocator within task body, this is a definite
396 -- violation of No_Allocators_After_Elaboration we can detect.
398 if Nkind (Original_Node (Parent (P))) = N_Task_Body then
399 Check_Restriction (No_Allocators_After_Elaboration, N);
403 -- The other case is appearence in a subprogram body. This may
404 -- be a violation if this is a library level subprogram, and it
405 -- turns out to be used as the main program, but only the
406 -- binder knows that, so just record the occurrence.
408 if Nkind (Original_Node (Parent (P))) = N_Subprogram_Body
409 and then Nkind (Parent (Parent (P))) = N_Compilation_Unit
411 Set_Has_Allocator (Current_Sem_Unit);
420 -- Analyze the allocator
422 if Nkind (E) = N_Qualified_Expression then
423 Acc_Type := Create_Itype (E_Allocator_Type, N);
424 Set_Etype (Acc_Type, Acc_Type);
425 Find_Type (Subtype_Mark (E));
427 -- Analyze the qualified expression, and apply the name resolution
428 -- rule given in 4.7 (3).
431 Type_Id := Etype (E);
432 Set_Directly_Designated_Type (Acc_Type, Type_Id);
434 Resolve (Expression (E), Type_Id);
436 if Is_Limited_Type (Type_Id)
437 and then Comes_From_Source (N)
438 and then not In_Instance_Body
440 if not OK_For_Limited_Init (Type_Id, Expression (E)) then
441 Error_Msg_N ("initialization not allowed for limited types", N);
442 Explain_Limited_Type (Type_Id, N);
446 -- A qualified expression requires an exact match of the type,
447 -- class-wide matching is not allowed.
449 -- if Is_Class_Wide_Type (Type_Id)
450 -- and then Base_Type
451 -- (Etype (Expression (E))) /= Base_Type (Type_Id)
453 -- Wrong_Type (Expression (E), Type_Id);
456 Check_Non_Static_Context (Expression (E));
458 -- We don't analyze the qualified expression itself because it's
459 -- part of the allocator
461 Set_Etype (E, Type_Id);
463 -- Case where allocator has a subtype indication
468 Base_Typ : Entity_Id;
471 -- If the allocator includes a N_Subtype_Indication then a
472 -- constraint is present, otherwise the node is a subtype mark.
473 -- Introduce an explicit subtype declaration into the tree
474 -- defining some anonymous subtype and rewrite the allocator to
475 -- use this subtype rather than the subtype indication.
477 -- It is important to introduce the explicit subtype declaration
478 -- so that the bounds of the subtype indication are attached to
479 -- the tree in case the allocator is inside a generic unit.
481 if Nkind (E) = N_Subtype_Indication then
483 -- A constraint is only allowed for a composite type in Ada
484 -- 95. In Ada 83, a constraint is also allowed for an
485 -- access-to-composite type, but the constraint is ignored.
487 Find_Type (Subtype_Mark (E));
488 Base_Typ := Entity (Subtype_Mark (E));
490 if Is_Elementary_Type (Base_Typ) then
491 if not (Ada_Version = Ada_83
492 and then Is_Access_Type (Base_Typ))
494 Error_Msg_N ("constraint not allowed here", E);
496 if Nkind (Constraint (E)) =
497 N_Index_Or_Discriminant_Constraint
499 Error_Msg_N -- CODEFIX
500 ("\if qualified expression was meant, " &
501 "use apostrophe", Constraint (E));
505 -- Get rid of the bogus constraint:
507 Rewrite (E, New_Copy_Tree (Subtype_Mark (E)));
508 Analyze_Allocator (N);
511 -- Ada 2005, AI-363: if the designated type has a constrained
512 -- partial view, it cannot receive a discriminant constraint,
513 -- and the allocated object is unconstrained.
515 elsif Ada_Version >= Ada_2005
516 and then Has_Constrained_Partial_View (Base_Typ)
519 ("constraint no allowed when type " &
520 "has a constrained partial view", Constraint (E));
523 if Expander_Active then
524 Def_Id := Make_Temporary (Loc, 'S');
527 Make_Subtype_Declaration (Loc,
528 Defining_Identifier => Def_Id,
529 Subtype_Indication => Relocate_Node (E)));
531 if Sav_Errs /= Serious_Errors_Detected
532 and then Nkind (Constraint (E)) =
533 N_Index_Or_Discriminant_Constraint
535 Error_Msg_N -- CODEFIX
536 ("if qualified expression was meant, " &
537 "use apostrophe!", Constraint (E));
540 E := New_Occurrence_Of (Def_Id, Loc);
541 Rewrite (Expression (N), E);
545 Type_Id := Process_Subtype (E, N);
546 Acc_Type := Create_Itype (E_Allocator_Type, N);
547 Set_Etype (Acc_Type, Acc_Type);
548 Set_Directly_Designated_Type (Acc_Type, Type_Id);
549 Check_Fully_Declared (Type_Id, N);
551 -- Ada 2005 (AI-231): If the designated type is itself an access
552 -- type that excludes null, its default initialization will
553 -- be a null object, and we can insert an unconditional raise
554 -- before the allocator.
556 -- Ada 2012 (AI-104): A not null indication here is altogether
559 if Can_Never_Be_Null (Type_Id) then
561 Not_Null_Check : constant Node_Id :=
562 Make_Raise_Constraint_Error (Sloc (E),
563 Reason => CE_Null_Not_Allowed);
566 if Ada_Version >= Ada_2012 then
568 ("an uninitialized allocator cannot have"
569 & " a null exclusion", N);
571 elsif Expander_Active then
572 Insert_Action (N, Not_Null_Check);
573 Analyze (Not_Null_Check);
576 Error_Msg_N ("null value not allowed here?", E);
581 -- Check restriction against dynamically allocated protected
582 -- objects. Note that when limited aggregates are supported,
583 -- a similar test should be applied to an allocator with a
584 -- qualified expression ???
586 if Is_Protected_Type (Type_Id) then
587 Check_Restriction (No_Protected_Type_Allocators, N);
590 -- Check for missing initialization. Skip this check if we already
591 -- had errors on analyzing the allocator, since in that case these
592 -- are probably cascaded errors.
594 if Is_Indefinite_Subtype (Type_Id)
595 and then Serious_Errors_Detected = Sav_Errs
597 if Is_Class_Wide_Type (Type_Id) then
599 ("initialization required in class-wide allocation", N);
601 if Ada_Version < Ada_2005
602 and then Is_Limited_Type (Type_Id)
604 Error_Msg_N ("unconstrained allocation not allowed", N);
606 if Is_Array_Type (Type_Id) then
608 ("\constraint with array bounds required", N);
610 elsif Has_Unknown_Discriminants (Type_Id) then
613 else pragma Assert (Has_Discriminants (Type_Id));
615 ("\constraint with discriminant values required", N);
618 -- Limited Ada 2005 and general non-limited case
622 ("uninitialized unconstrained allocation not allowed",
625 if Is_Array_Type (Type_Id) then
627 ("\qualified expression or constraint with " &
628 "array bounds required", N);
630 elsif Has_Unknown_Discriminants (Type_Id) then
631 Error_Msg_N ("\qualified expression required", N);
633 else pragma Assert (Has_Discriminants (Type_Id));
635 ("\qualified expression or constraint with " &
636 "discriminant values required", N);
644 if Is_Abstract_Type (Type_Id) then
645 Error_Msg_N ("cannot allocate abstract object", E);
648 if Has_Task (Designated_Type (Acc_Type)) then
649 Check_Restriction (No_Tasking, N);
650 Check_Restriction (Max_Tasks, N);
651 Check_Restriction (No_Task_Allocators, N);
653 -- Check that an allocator with task parts isn't for a nested access
654 -- type when restriction No_Task_Hierarchy applies.
656 if not Is_Library_Level_Entity (Acc_Type) then
657 Check_Restriction (No_Task_Hierarchy, N);
661 -- Check that an allocator of a nested access type doesn't create a
662 -- protected object when restriction No_Local_Protected_Objects applies.
663 -- We don't have an equivalent to Has_Task for protected types, so only
664 -- cases where the designated type itself is a protected type are
665 -- currently checked. ???
667 if Is_Protected_Type (Designated_Type (Acc_Type))
668 and then not Is_Library_Level_Entity (Acc_Type)
670 Check_Restriction (No_Local_Protected_Objects, N);
673 -- If the No_Streams restriction is set, check that the type of the
674 -- object is not, and does not contain, any subtype derived from
675 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
676 -- Has_Stream just for efficiency reasons. There is no point in
677 -- spending time on a Has_Stream check if the restriction is not set.
679 if Restriction_Check_Required (No_Streams) then
680 if Has_Stream (Designated_Type (Acc_Type)) then
681 Check_Restriction (No_Streams, N);
685 Set_Etype (N, Acc_Type);
687 if not Is_Library_Level_Entity (Acc_Type) then
688 Check_Restriction (No_Local_Allocators, N);
691 if Serious_Errors_Detected > Sav_Errs then
692 Set_Error_Posted (N);
693 Set_Etype (N, Any_Type);
695 end Analyze_Allocator;
697 ---------------------------
698 -- Analyze_Arithmetic_Op --
699 ---------------------------
701 procedure Analyze_Arithmetic_Op (N : Node_Id) is
702 L : constant Node_Id := Left_Opnd (N);
703 R : constant Node_Id := Right_Opnd (N);
707 Candidate_Type := Empty;
708 Analyze_Expression (L);
709 Analyze_Expression (R);
711 -- If the entity is already set, the node is the instantiation of a
712 -- generic node with a non-local reference, or was manufactured by a
713 -- call to Make_Op_xxx. In either case the entity is known to be valid,
714 -- and we do not need to collect interpretations, instead we just get
715 -- the single possible interpretation.
719 if Present (Op_Id) then
720 if Ekind (Op_Id) = E_Operator then
722 if Nkind_In (N, N_Op_Divide, N_Op_Mod, N_Op_Multiply, N_Op_Rem)
723 and then Treat_Fixed_As_Integer (N)
727 Set_Etype (N, Any_Type);
728 Find_Arithmetic_Types (L, R, Op_Id, N);
732 Set_Etype (N, Any_Type);
733 Add_One_Interp (N, Op_Id, Etype (Op_Id));
736 -- Entity is not already set, so we do need to collect interpretations
739 Op_Id := Get_Name_Entity_Id (Chars (N));
740 Set_Etype (N, Any_Type);
742 while Present (Op_Id) loop
743 if Ekind (Op_Id) = E_Operator
744 and then Present (Next_Entity (First_Entity (Op_Id)))
746 Find_Arithmetic_Types (L, R, Op_Id, N);
748 -- The following may seem superfluous, because an operator cannot
749 -- be generic, but this ignores the cleverness of the author of
752 elsif Is_Overloadable (Op_Id) then
753 Analyze_User_Defined_Binary_Op (N, Op_Id);
756 Op_Id := Homonym (Op_Id);
761 end Analyze_Arithmetic_Op;
767 -- Function, procedure, and entry calls are checked here. The Name in
768 -- the call may be overloaded. The actuals have been analyzed and may
769 -- themselves be overloaded. On exit from this procedure, the node N
770 -- may have zero, one or more interpretations. In the first case an
771 -- error message is produced. In the last case, the node is flagged
772 -- as overloaded and the interpretations are collected in All_Interp.
774 -- If the name is an Access_To_Subprogram, it cannot be overloaded, but
775 -- the type-checking is similar to that of other calls.
777 procedure Analyze_Call (N : Node_Id) is
778 Actuals : constant List_Id := Parameter_Associations (N);
783 Success : Boolean := False;
785 Deref : Boolean := False;
786 -- Flag indicates whether an interpretation of the prefix is a
787 -- parameterless call that returns an access_to_subprogram.
789 function Name_Denotes_Function return Boolean;
790 -- If the type of the name is an access to subprogram, this may be the
791 -- type of a name, or the return type of the function being called. If
792 -- the name is not an entity then it can denote a protected function.
793 -- Until we distinguish Etype from Return_Type, we must use this routine
794 -- to resolve the meaning of the name in the call.
796 procedure No_Interpretation;
797 -- Output error message when no valid interpretation exists
799 ---------------------------
800 -- Name_Denotes_Function --
801 ---------------------------
803 function Name_Denotes_Function return Boolean is
805 if Is_Entity_Name (Nam) then
806 return Ekind (Entity (Nam)) = E_Function;
808 elsif Nkind (Nam) = N_Selected_Component then
809 return Ekind (Entity (Selector_Name (Nam))) = E_Function;
814 end Name_Denotes_Function;
816 -----------------------
817 -- No_Interpretation --
818 -----------------------
820 procedure No_Interpretation is
821 L : constant Boolean := Is_List_Member (N);
822 K : constant Node_Kind := Nkind (Parent (N));
825 -- If the node is in a list whose parent is not an expression then it
826 -- must be an attempted procedure call.
828 if L and then K not in N_Subexpr then
829 if Ekind (Entity (Nam)) = E_Generic_Procedure then
831 ("must instantiate generic procedure& before call",
835 ("procedure or entry name expected", Nam);
838 -- Check for tasking cases where only an entry call will do
841 and then Nkind_In (K, N_Entry_Call_Alternative,
842 N_Triggering_Alternative)
844 Error_Msg_N ("entry name expected", Nam);
846 -- Otherwise give general error message
849 Error_Msg_N ("invalid prefix in call", Nam);
851 end No_Interpretation;
853 -- Start of processing for Analyze_Call
856 -- Initialize the type of the result of the call to the error type,
857 -- which will be reset if the type is successfully resolved.
859 Set_Etype (N, Any_Type);
863 if not Is_Overloaded (Nam) then
865 -- Only one interpretation to check
867 if Ekind (Etype (Nam)) = E_Subprogram_Type then
868 Nam_Ent := Etype (Nam);
870 -- If the prefix is an access_to_subprogram, this may be an indirect
871 -- call. This is the case if the name in the call is not an entity
872 -- name, or if it is a function name in the context of a procedure
873 -- call. In this latter case, we have a call to a parameterless
874 -- function that returns a pointer_to_procedure which is the entity
875 -- being called. Finally, F (X) may be a call to a parameterless
876 -- function that returns a pointer to a function with parameters.
878 elsif Is_Access_Type (Etype (Nam))
879 and then Ekind (Designated_Type (Etype (Nam))) = E_Subprogram_Type
881 (not Name_Denotes_Function
882 or else Nkind (N) = N_Procedure_Call_Statement
884 (Nkind (Parent (N)) /= N_Explicit_Dereference
885 and then Is_Entity_Name (Nam)
886 and then No (First_Formal (Entity (Nam)))
887 and then Present (Actuals)))
889 Nam_Ent := Designated_Type (Etype (Nam));
890 Insert_Explicit_Dereference (Nam);
892 -- Selected component case. Simple entry or protected operation,
893 -- where the entry name is given by the selector name.
895 elsif Nkind (Nam) = N_Selected_Component then
896 Nam_Ent := Entity (Selector_Name (Nam));
898 if not Ekind_In (Nam_Ent, E_Entry,
903 Error_Msg_N ("name in call is not a callable entity", Nam);
904 Set_Etype (N, Any_Type);
908 -- If the name is an Indexed component, it can be a call to a member
909 -- of an entry family. The prefix must be a selected component whose
910 -- selector is the entry. Analyze_Procedure_Call normalizes several
911 -- kinds of call into this form.
913 elsif Nkind (Nam) = N_Indexed_Component then
914 if Nkind (Prefix (Nam)) = N_Selected_Component then
915 Nam_Ent := Entity (Selector_Name (Prefix (Nam)));
917 Error_Msg_N ("name in call is not a callable entity", Nam);
918 Set_Etype (N, Any_Type);
922 elsif not Is_Entity_Name (Nam) then
923 Error_Msg_N ("name in call is not a callable entity", Nam);
924 Set_Etype (N, Any_Type);
928 Nam_Ent := Entity (Nam);
930 -- If no interpretations, give error message
932 if not Is_Overloadable (Nam_Ent) then
938 -- Operations generated for RACW stub types are called only through
939 -- dispatching, and can never be the static interpretation of a call.
941 if Is_RACW_Stub_Type_Operation (Nam_Ent) then
946 Analyze_One_Call (N, Nam_Ent, True, Success);
948 -- If this is an indirect call, the return type of the access_to
949 -- subprogram may be an incomplete type. At the point of the call,
950 -- use the full type if available, and at the same time update the
951 -- return type of the access_to_subprogram.
954 and then Nkind (Nam) = N_Explicit_Dereference
955 and then Ekind (Etype (N)) = E_Incomplete_Type
956 and then Present (Full_View (Etype (N)))
958 Set_Etype (N, Full_View (Etype (N)));
959 Set_Etype (Nam_Ent, Etype (N));
963 -- An overloaded selected component must denote overloaded operations
964 -- of a concurrent type. The interpretations are attached to the
965 -- simple name of those operations.
967 if Nkind (Nam) = N_Selected_Component then
968 Nam := Selector_Name (Nam);
971 Get_First_Interp (Nam, X, It);
973 while Present (It.Nam) loop
977 -- Name may be call that returns an access to subprogram, or more
978 -- generally an overloaded expression one of whose interpretations
979 -- yields an access to subprogram. If the name is an entity, we do
980 -- not dereference, because the node is a call that returns the
981 -- access type: note difference between f(x), where the call may
982 -- return an access subprogram type, and f(x)(y), where the type
983 -- returned by the call to f is implicitly dereferenced to analyze
986 if Is_Access_Type (Nam_Ent) then
987 Nam_Ent := Designated_Type (Nam_Ent);
989 elsif Is_Access_Type (Etype (Nam_Ent))
991 (not Is_Entity_Name (Nam)
992 or else Nkind (N) = N_Procedure_Call_Statement)
993 and then Ekind (Designated_Type (Etype (Nam_Ent)))
996 Nam_Ent := Designated_Type (Etype (Nam_Ent));
998 if Is_Entity_Name (Nam) then
1003 -- If the call has been rewritten from a prefixed call, the first
1004 -- parameter has been analyzed, but may need a subsequent
1005 -- dereference, so skip its analysis now.
1007 if N /= Original_Node (N)
1008 and then Nkind (Original_Node (N)) = Nkind (N)
1009 and then Nkind (Name (N)) /= Nkind (Name (Original_Node (N)))
1010 and then Present (Parameter_Associations (N))
1011 and then Present (Etype (First (Parameter_Associations (N))))
1014 (N, Nam_Ent, False, Success, Skip_First => True);
1016 Analyze_One_Call (N, Nam_Ent, False, Success);
1019 -- If the interpretation succeeds, mark the proper type of the
1020 -- prefix (any valid candidate will do). If not, remove the
1021 -- candidate interpretation. This only needs to be done for
1022 -- overloaded protected operations, for other entities disambi-
1023 -- guation is done directly in Resolve.
1027 and then Nkind (Parent (N)) /= N_Explicit_Dereference
1029 Set_Entity (Nam, It.Nam);
1030 Insert_Explicit_Dereference (Nam);
1031 Set_Etype (Nam, Nam_Ent);
1034 Set_Etype (Nam, It.Typ);
1037 elsif Nkind_In (Name (N), N_Selected_Component,
1043 Get_Next_Interp (X, It);
1046 -- If the name is the result of a function call, it can only
1047 -- be a call to a function returning an access to subprogram.
1048 -- Insert explicit dereference.
1050 if Nkind (Nam) = N_Function_Call then
1051 Insert_Explicit_Dereference (Nam);
1054 if Etype (N) = Any_Type then
1056 -- None of the interpretations is compatible with the actuals
1058 Diagnose_Call (N, Nam);
1060 -- Special checks for uninstantiated put routines
1062 if Nkind (N) = N_Procedure_Call_Statement
1063 and then Is_Entity_Name (Nam)
1064 and then Chars (Nam) = Name_Put
1065 and then List_Length (Actuals) = 1
1068 Arg : constant Node_Id := First (Actuals);
1072 if Nkind (Arg) = N_Parameter_Association then
1073 Typ := Etype (Explicit_Actual_Parameter (Arg));
1078 if Is_Signed_Integer_Type (Typ) then
1080 ("possible missing instantiation of " &
1081 "'Text_'I'O.'Integer_'I'O!", Nam);
1083 elsif Is_Modular_Integer_Type (Typ) then
1085 ("possible missing instantiation of " &
1086 "'Text_'I'O.'Modular_'I'O!", Nam);
1088 elsif Is_Floating_Point_Type (Typ) then
1090 ("possible missing instantiation of " &
1091 "'Text_'I'O.'Float_'I'O!", Nam);
1093 elsif Is_Ordinary_Fixed_Point_Type (Typ) then
1095 ("possible missing instantiation of " &
1096 "'Text_'I'O.'Fixed_'I'O!", Nam);
1098 elsif Is_Decimal_Fixed_Point_Type (Typ) then
1100 ("possible missing instantiation of " &
1101 "'Text_'I'O.'Decimal_'I'O!", Nam);
1103 elsif Is_Enumeration_Type (Typ) then
1105 ("possible missing instantiation of " &
1106 "'Text_'I'O.'Enumeration_'I'O!", Nam);
1111 elsif not Is_Overloaded (N)
1112 and then Is_Entity_Name (Nam)
1114 -- Resolution yields a single interpretation. Verify that the
1115 -- reference has capitalization consistent with the declaration.
1117 Set_Entity_With_Style_Check (Nam, Entity (Nam));
1118 Generate_Reference (Entity (Nam), Nam);
1120 Set_Etype (Nam, Etype (Entity (Nam)));
1122 Remove_Abstract_Operations (N);
1129 -----------------------------
1130 -- Analyze_Case_Expression --
1131 -----------------------------
1133 procedure Analyze_Case_Expression (N : Node_Id) is
1134 Expr : constant Node_Id := Expression (N);
1135 FirstX : constant Node_Id := Expression (First (Alternatives (N)));
1137 Exp_Type : Entity_Id;
1138 Exp_Btype : Entity_Id;
1140 Dont_Care : Boolean;
1141 Others_Present : Boolean;
1143 procedure Non_Static_Choice_Error (Choice : Node_Id);
1144 -- Error routine invoked by the generic instantiation below when
1145 -- the case expression has a non static choice.
1147 package Case_Choices_Processing is new
1148 Generic_Choices_Processing
1149 (Get_Alternatives => Alternatives,
1150 Get_Choices => Discrete_Choices,
1151 Process_Empty_Choice => No_OP,
1152 Process_Non_Static_Choice => Non_Static_Choice_Error,
1153 Process_Associated_Node => No_OP);
1154 use Case_Choices_Processing;
1156 -----------------------------
1157 -- Non_Static_Choice_Error --
1158 -----------------------------
1160 procedure Non_Static_Choice_Error (Choice : Node_Id) is
1162 Flag_Non_Static_Expr
1163 ("choice given in case expression is not static!", Choice);
1164 end Non_Static_Choice_Error;
1166 -- Start of processing for Analyze_Case_Expression
1169 if Comes_From_Source (N) then
1170 Check_Compiler_Unit (N);
1173 Analyze_And_Resolve (Expr, Any_Discrete);
1174 Check_Unset_Reference (Expr);
1175 Exp_Type := Etype (Expr);
1176 Exp_Btype := Base_Type (Exp_Type);
1178 Alt := First (Alternatives (N));
1179 while Present (Alt) loop
1180 Analyze (Expression (Alt));
1184 if not Is_Overloaded (FirstX) then
1185 Set_Etype (N, Etype (FirstX));
1193 Set_Etype (N, Any_Type);
1195 Get_First_Interp (FirstX, I, It);
1196 while Present (It.Nam) loop
1198 -- For each intepretation of the first expression, we only
1199 -- add the intepretation if every other expression in the
1200 -- case expression alternatives has a compatible type.
1202 Alt := Next (First (Alternatives (N)));
1203 while Present (Alt) loop
1204 exit when not Has_Compatible_Type (Expression (Alt), It.Typ);
1209 Add_One_Interp (N, It.Typ, It.Typ);
1212 Get_Next_Interp (I, It);
1217 Exp_Btype := Base_Type (Exp_Type);
1219 -- The expression must be of a discrete type which must be determinable
1220 -- independently of the context in which the expression occurs, but
1221 -- using the fact that the expression must be of a discrete type.
1222 -- Moreover, the type this expression must not be a character literal
1223 -- (which is always ambiguous).
1225 -- If error already reported by Resolve, nothing more to do
1227 if Exp_Btype = Any_Discrete
1228 or else Exp_Btype = Any_Type
1232 elsif Exp_Btype = Any_Character then
1234 ("character literal as case expression is ambiguous", Expr);
1238 -- If the case expression is a formal object of mode in out, then
1239 -- treat it as having a nonstatic subtype by forcing use of the base
1240 -- type (which has to get passed to Check_Case_Choices below). Also
1241 -- use base type when the case expression is parenthesized.
1243 if Paren_Count (Expr) > 0
1244 or else (Is_Entity_Name (Expr)
1245 and then Ekind (Entity (Expr)) = E_Generic_In_Out_Parameter)
1247 Exp_Type := Exp_Btype;
1250 -- Call instantiated Analyze_Choices which does the rest of the work
1252 Analyze_Choices (N, Exp_Type, Dont_Care, Others_Present);
1254 if Exp_Type = Universal_Integer and then not Others_Present then
1256 ("case on universal integer requires OTHERS choice", Expr);
1258 end Analyze_Case_Expression;
1260 ---------------------------
1261 -- Analyze_Comparison_Op --
1262 ---------------------------
1264 procedure Analyze_Comparison_Op (N : Node_Id) is
1265 L : constant Node_Id := Left_Opnd (N);
1266 R : constant Node_Id := Right_Opnd (N);
1267 Op_Id : Entity_Id := Entity (N);
1270 Set_Etype (N, Any_Type);
1271 Candidate_Type := Empty;
1273 Analyze_Expression (L);
1274 Analyze_Expression (R);
1276 if Present (Op_Id) then
1277 if Ekind (Op_Id) = E_Operator then
1278 Find_Comparison_Types (L, R, Op_Id, N);
1280 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1283 if Is_Overloaded (L) then
1284 Set_Etype (L, Intersect_Types (L, R));
1288 Op_Id := Get_Name_Entity_Id (Chars (N));
1289 while Present (Op_Id) loop
1290 if Ekind (Op_Id) = E_Operator then
1291 Find_Comparison_Types (L, R, Op_Id, N);
1293 Analyze_User_Defined_Binary_Op (N, Op_Id);
1296 Op_Id := Homonym (Op_Id);
1301 end Analyze_Comparison_Op;
1303 ---------------------------
1304 -- Analyze_Concatenation --
1305 ---------------------------
1307 procedure Analyze_Concatenation (N : Node_Id) is
1309 -- We wish to avoid deep recursion, because concatenations are often
1310 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1311 -- operands nonrecursively until we find something that is not a
1312 -- concatenation (A in this case), or has already been analyzed. We
1313 -- analyze that, and then walk back up the tree following Parent
1314 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1315 -- work at each level. The Parent pointers allow us to avoid recursion,
1316 -- and thus avoid running out of memory.
1322 Candidate_Type := Empty;
1324 -- The following code is equivalent to:
1326 -- Set_Etype (N, Any_Type);
1327 -- Analyze_Expression (Left_Opnd (N));
1328 -- Analyze_Concatenation_Rest (N);
1330 -- where the Analyze_Expression call recurses back here if the left
1331 -- operand is a concatenation.
1333 -- Walk down left operands
1336 Set_Etype (NN, Any_Type);
1337 L := Left_Opnd (NN);
1338 exit when Nkind (L) /= N_Op_Concat or else Analyzed (L);
1342 -- Now (given the above example) NN is A&B and L is A
1344 -- First analyze L ...
1346 Analyze_Expression (L);
1348 -- ... then walk NN back up until we reach N (where we started), calling
1349 -- Analyze_Concatenation_Rest along the way.
1352 Analyze_Concatenation_Rest (NN);
1356 end Analyze_Concatenation;
1358 --------------------------------
1359 -- Analyze_Concatenation_Rest --
1360 --------------------------------
1362 -- If the only one-dimensional array type in scope is String,
1363 -- this is the resulting type of the operation. Otherwise there
1364 -- will be a concatenation operation defined for each user-defined
1365 -- one-dimensional array.
1367 procedure Analyze_Concatenation_Rest (N : Node_Id) is
1368 L : constant Node_Id := Left_Opnd (N);
1369 R : constant Node_Id := Right_Opnd (N);
1370 Op_Id : Entity_Id := Entity (N);
1375 Analyze_Expression (R);
1377 -- If the entity is present, the node appears in an instance, and
1378 -- denotes a predefined concatenation operation. The resulting type is
1379 -- obtained from the arguments when possible. If the arguments are
1380 -- aggregates, the array type and the concatenation type must be
1383 if Present (Op_Id) then
1384 if Ekind (Op_Id) = E_Operator then
1385 LT := Base_Type (Etype (L));
1386 RT := Base_Type (Etype (R));
1388 if Is_Array_Type (LT)
1389 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
1391 Add_One_Interp (N, Op_Id, LT);
1393 elsif Is_Array_Type (RT)
1394 and then LT = Base_Type (Component_Type (RT))
1396 Add_One_Interp (N, Op_Id, RT);
1398 -- If one operand is a string type or a user-defined array type,
1399 -- and the other is a literal, result is of the specific type.
1402 (Root_Type (LT) = Standard_String
1403 or else Scope (LT) /= Standard_Standard)
1404 and then Etype (R) = Any_String
1406 Add_One_Interp (N, Op_Id, LT);
1409 (Root_Type (RT) = Standard_String
1410 or else Scope (RT) /= Standard_Standard)
1411 and then Etype (L) = Any_String
1413 Add_One_Interp (N, Op_Id, RT);
1415 elsif not Is_Generic_Type (Etype (Op_Id)) then
1416 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1419 -- Type and its operations must be visible
1421 Set_Entity (N, Empty);
1422 Analyze_Concatenation (N);
1426 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1430 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
1431 while Present (Op_Id) loop
1432 if Ekind (Op_Id) = E_Operator then
1434 -- Do not consider operators declared in dead code, they can
1435 -- not be part of the resolution.
1437 if Is_Eliminated (Op_Id) then
1440 Find_Concatenation_Types (L, R, Op_Id, N);
1444 Analyze_User_Defined_Binary_Op (N, Op_Id);
1447 Op_Id := Homonym (Op_Id);
1452 end Analyze_Concatenation_Rest;
1454 ------------------------------------
1455 -- Analyze_Conditional_Expression --
1456 ------------------------------------
1458 procedure Analyze_Conditional_Expression (N : Node_Id) is
1459 Condition : constant Node_Id := First (Expressions (N));
1460 Then_Expr : constant Node_Id := Next (Condition);
1461 Else_Expr : Node_Id;
1464 -- Defend against error of missing expressions from previous error
1466 if No (Then_Expr) then
1470 Else_Expr := Next (Then_Expr);
1472 if Comes_From_Source (N) then
1473 Check_Compiler_Unit (N);
1476 Analyze_Expression (Condition);
1477 Analyze_Expression (Then_Expr);
1479 if Present (Else_Expr) then
1480 Analyze_Expression (Else_Expr);
1483 -- If then expression not overloaded, then that decides the type
1485 if not Is_Overloaded (Then_Expr) then
1486 Set_Etype (N, Etype (Then_Expr));
1488 -- Case where then expression is overloaded
1496 Set_Etype (N, Any_Type);
1497 Get_First_Interp (Then_Expr, I, It);
1498 while Present (It.Nam) loop
1500 -- For each possible intepretation of the Then Expression,
1501 -- add it only if the else expression has a compatible type.
1503 -- Is this right if Else_Expr is empty?
1505 if Has_Compatible_Type (Else_Expr, It.Typ) then
1506 Add_One_Interp (N, It.Typ, It.Typ);
1509 Get_Next_Interp (I, It);
1513 end Analyze_Conditional_Expression;
1515 -------------------------
1516 -- Analyze_Equality_Op --
1517 -------------------------
1519 procedure Analyze_Equality_Op (N : Node_Id) is
1520 Loc : constant Source_Ptr := Sloc (N);
1521 L : constant Node_Id := Left_Opnd (N);
1522 R : constant Node_Id := Right_Opnd (N);
1526 Set_Etype (N, Any_Type);
1527 Candidate_Type := Empty;
1529 Analyze_Expression (L);
1530 Analyze_Expression (R);
1532 -- If the entity is set, the node is a generic instance with a non-local
1533 -- reference to the predefined operator or to a user-defined function.
1534 -- It can also be an inequality that is expanded into the negation of a
1535 -- call to a user-defined equality operator.
1537 -- For the predefined case, the result is Boolean, regardless of the
1538 -- type of the operands. The operands may even be limited, if they are
1539 -- generic actuals. If they are overloaded, label the left argument with
1540 -- the common type that must be present, or with the type of the formal
1541 -- of the user-defined function.
1543 if Present (Entity (N)) then
1544 Op_Id := Entity (N);
1546 if Ekind (Op_Id) = E_Operator then
1547 Add_One_Interp (N, Op_Id, Standard_Boolean);
1549 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1552 if Is_Overloaded (L) then
1553 if Ekind (Op_Id) = E_Operator then
1554 Set_Etype (L, Intersect_Types (L, R));
1556 Set_Etype (L, Etype (First_Formal (Op_Id)));
1561 Op_Id := Get_Name_Entity_Id (Chars (N));
1562 while Present (Op_Id) loop
1563 if Ekind (Op_Id) = E_Operator then
1564 Find_Equality_Types (L, R, Op_Id, N);
1566 Analyze_User_Defined_Binary_Op (N, Op_Id);
1569 Op_Id := Homonym (Op_Id);
1573 -- If there was no match, and the operator is inequality, this may
1574 -- be a case where inequality has not been made explicit, as for
1575 -- tagged types. Analyze the node as the negation of an equality
1576 -- operation. This cannot be done earlier, because before analysis
1577 -- we cannot rule out the presence of an explicit inequality.
1579 if Etype (N) = Any_Type
1580 and then Nkind (N) = N_Op_Ne
1582 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1583 while Present (Op_Id) loop
1584 if Ekind (Op_Id) = E_Operator then
1585 Find_Equality_Types (L, R, Op_Id, N);
1587 Analyze_User_Defined_Binary_Op (N, Op_Id);
1590 Op_Id := Homonym (Op_Id);
1593 if Etype (N) /= Any_Type then
1594 Op_Id := Entity (N);
1600 Left_Opnd => Left_Opnd (N),
1601 Right_Opnd => Right_Opnd (N))));
1603 Set_Entity (Right_Opnd (N), Op_Id);
1609 end Analyze_Equality_Op;
1611 ----------------------------------
1612 -- Analyze_Explicit_Dereference --
1613 ----------------------------------
1615 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1616 Loc : constant Source_Ptr := Sloc (N);
1617 P : constant Node_Id := Prefix (N);
1623 function Is_Function_Type return Boolean;
1624 -- Check whether node may be interpreted as an implicit function call
1626 ----------------------
1627 -- Is_Function_Type --
1628 ----------------------
1630 function Is_Function_Type return Boolean is
1635 if not Is_Overloaded (N) then
1636 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1637 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1640 Get_First_Interp (N, I, It);
1641 while Present (It.Nam) loop
1642 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1643 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1648 Get_Next_Interp (I, It);
1653 end Is_Function_Type;
1655 -- Start of processing for Analyze_Explicit_Dereference
1659 Set_Etype (N, Any_Type);
1661 -- Test for remote access to subprogram type, and if so return
1662 -- after rewriting the original tree.
1664 if Remote_AST_E_Dereference (P) then
1668 -- Normal processing for other than remote access to subprogram type
1670 if not Is_Overloaded (P) then
1671 if Is_Access_Type (Etype (P)) then
1673 -- Set the Etype. We need to go through Is_For_Access_Subtypes to
1674 -- avoid other problems caused by the Private_Subtype and it is
1675 -- safe to go to the Base_Type because this is the same as
1676 -- converting the access value to its Base_Type.
1679 DT : Entity_Id := Designated_Type (Etype (P));
1682 if Ekind (DT) = E_Private_Subtype
1683 and then Is_For_Access_Subtype (DT)
1685 DT := Base_Type (DT);
1688 -- An explicit dereference is a legal occurrence of an
1689 -- incomplete type imported through a limited_with clause,
1690 -- if the full view is visible.
1692 if From_With_Type (DT)
1693 and then not From_With_Type (Scope (DT))
1695 (Is_Immediately_Visible (Scope (DT))
1697 (Is_Child_Unit (Scope (DT))
1698 and then Is_Visible_Child_Unit (Scope (DT))))
1700 Set_Etype (N, Available_View (DT));
1707 elsif Etype (P) /= Any_Type then
1708 Error_Msg_N ("prefix of dereference must be an access type", N);
1713 Get_First_Interp (P, I, It);
1714 while Present (It.Nam) loop
1717 if Is_Access_Type (T) then
1718 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1721 Get_Next_Interp (I, It);
1724 -- Error if no interpretation of the prefix has an access type
1726 if Etype (N) = Any_Type then
1728 ("access type required in prefix of explicit dereference", P);
1729 Set_Etype (N, Any_Type);
1735 and then Nkind (Parent (N)) /= N_Indexed_Component
1737 and then (Nkind (Parent (N)) /= N_Function_Call
1738 or else N /= Name (Parent (N)))
1740 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1741 or else N /= Name (Parent (N)))
1743 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1744 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1746 (Attribute_Name (Parent (N)) /= Name_Address
1748 Attribute_Name (Parent (N)) /= Name_Access))
1750 -- Name is a function call with no actuals, in a context that
1751 -- requires deproceduring (including as an actual in an enclosing
1752 -- function or procedure call). There are some pathological cases
1753 -- where the prefix might include functions that return access to
1754 -- subprograms and others that return a regular type. Disambiguation
1755 -- of those has to take place in Resolve.
1758 Make_Function_Call (Loc,
1759 Name => Make_Explicit_Dereference (Loc, P),
1760 Parameter_Associations => New_List);
1762 -- If the prefix is overloaded, remove operations that have formals,
1763 -- we know that this is a parameterless call.
1765 if Is_Overloaded (P) then
1766 Get_First_Interp (P, I, It);
1767 while Present (It.Nam) loop
1770 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1776 Get_Next_Interp (I, It);
1783 elsif not Is_Function_Type
1784 and then Is_Overloaded (N)
1786 -- The prefix may include access to subprograms and other access
1787 -- types. If the context selects the interpretation that is a
1788 -- function call (not a procedure call) we cannot rewrite the node
1789 -- yet, but we include the result of the call interpretation.
1791 Get_First_Interp (N, I, It);
1792 while Present (It.Nam) loop
1793 if Ekind (Base_Type (It.Typ)) = E_Subprogram_Type
1794 and then Etype (Base_Type (It.Typ)) /= Standard_Void_Type
1795 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
1797 Add_One_Interp (N, Etype (It.Typ), Etype (It.Typ));
1800 Get_Next_Interp (I, It);
1804 -- A value of remote access-to-class-wide must not be dereferenced
1807 Validate_Remote_Access_To_Class_Wide_Type (N);
1808 end Analyze_Explicit_Dereference;
1810 ------------------------
1811 -- Analyze_Expression --
1812 ------------------------
1814 procedure Analyze_Expression (N : Node_Id) is
1817 Check_Parameterless_Call (N);
1818 end Analyze_Expression;
1820 -------------------------------------
1821 -- Analyze_Expression_With_Actions --
1822 -------------------------------------
1824 procedure Analyze_Expression_With_Actions (N : Node_Id) is
1828 A := First (Actions (N));
1835 Analyze_Expression (Expression (N));
1836 Set_Etype (N, Etype (Expression (N)));
1837 end Analyze_Expression_With_Actions;
1839 ------------------------------------
1840 -- Analyze_Indexed_Component_Form --
1841 ------------------------------------
1843 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1844 P : constant Node_Id := Prefix (N);
1845 Exprs : constant List_Id := Expressions (N);
1851 procedure Process_Function_Call;
1852 -- Prefix in indexed component form is an overloadable entity,
1853 -- so the node is a function call. Reformat it as such.
1855 procedure Process_Indexed_Component;
1856 -- Prefix in indexed component form is actually an indexed component.
1857 -- This routine processes it, knowing that the prefix is already
1860 procedure Process_Indexed_Component_Or_Slice;
1861 -- An indexed component with a single index may designate a slice if
1862 -- the index is a subtype mark. This routine disambiguates these two
1863 -- cases by resolving the prefix to see if it is a subtype mark.
1865 procedure Process_Overloaded_Indexed_Component;
1866 -- If the prefix of an indexed component is overloaded, the proper
1867 -- interpretation is selected by the index types and the context.
1869 ---------------------------
1870 -- Process_Function_Call --
1871 ---------------------------
1873 procedure Process_Function_Call is
1877 Change_Node (N, N_Function_Call);
1879 Set_Parameter_Associations (N, Exprs);
1881 -- Analyze actuals prior to analyzing the call itself
1883 Actual := First (Parameter_Associations (N));
1884 while Present (Actual) loop
1886 Check_Parameterless_Call (Actual);
1888 -- Move to next actual. Note that we use Next, not Next_Actual
1889 -- here. The reason for this is a bit subtle. If a function call
1890 -- includes named associations, the parser recognizes the node as
1891 -- a call, and it is analyzed as such. If all associations are
1892 -- positional, the parser builds an indexed_component node, and
1893 -- it is only after analysis of the prefix that the construct
1894 -- is recognized as a call, in which case Process_Function_Call
1895 -- rewrites the node and analyzes the actuals. If the list of
1896 -- actuals is malformed, the parser may leave the node as an
1897 -- indexed component (despite the presence of named associations).
1898 -- The iterator Next_Actual is equivalent to Next if the list is
1899 -- positional, but follows the normalized chain of actuals when
1900 -- named associations are present. In this case normalization has
1901 -- not taken place, and actuals remain unanalyzed, which leads to
1902 -- subsequent crashes or loops if there is an attempt to continue
1903 -- analysis of the program.
1909 end Process_Function_Call;
1911 -------------------------------
1912 -- Process_Indexed_Component --
1913 -------------------------------
1915 procedure Process_Indexed_Component is
1917 Array_Type : Entity_Id;
1919 Pent : Entity_Id := Empty;
1922 Exp := First (Exprs);
1924 if Is_Overloaded (P) then
1925 Process_Overloaded_Indexed_Component;
1928 Array_Type := Etype (P);
1930 if Is_Entity_Name (P) then
1932 elsif Nkind (P) = N_Selected_Component
1933 and then Is_Entity_Name (Selector_Name (P))
1935 Pent := Entity (Selector_Name (P));
1938 -- Prefix must be appropriate for an array type, taking into
1939 -- account a possible implicit dereference.
1941 if Is_Access_Type (Array_Type) then
1942 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1943 Array_Type := Process_Implicit_Dereference_Prefix (Pent, P);
1946 if Is_Array_Type (Array_Type) then
1949 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1951 Set_Etype (N, Any_Type);
1953 if not Has_Compatible_Type
1954 (Exp, Entry_Index_Type (Pent))
1956 Error_Msg_N ("invalid index type in entry name", N);
1958 elsif Present (Next (Exp)) then
1959 Error_Msg_N ("too many subscripts in entry reference", N);
1962 Set_Etype (N, Etype (P));
1967 elsif Is_Record_Type (Array_Type)
1968 and then Remote_AST_I_Dereference (P)
1972 elsif Array_Type = Any_Type then
1973 Set_Etype (N, Any_Type);
1975 -- In most cases the analysis of the prefix will have emitted
1976 -- an error already, but if the prefix may be interpreted as a
1977 -- call in prefixed notation, the report is left to the caller.
1978 -- To prevent cascaded errors, report only if no previous ones.
1980 if Serious_Errors_Detected = 0 then
1981 Error_Msg_N ("invalid prefix in indexed component", P);
1983 if Nkind (P) = N_Expanded_Name then
1984 Error_Msg_NE ("\& is not visible", P, Selector_Name (P));
1990 -- Here we definitely have a bad indexing
1993 if Nkind (Parent (N)) = N_Requeue_Statement
1994 and then Present (Pent) and then Ekind (Pent) = E_Entry
1997 ("REQUEUE does not permit parameters", First (Exprs));
1999 elsif Is_Entity_Name (P)
2000 and then Etype (P) = Standard_Void_Type
2002 Error_Msg_NE ("incorrect use of&", P, Entity (P));
2005 Error_Msg_N ("array type required in indexed component", P);
2008 Set_Etype (N, Any_Type);
2012 Index := First_Index (Array_Type);
2013 while Present (Index) and then Present (Exp) loop
2014 if not Has_Compatible_Type (Exp, Etype (Index)) then
2015 Wrong_Type (Exp, Etype (Index));
2016 Set_Etype (N, Any_Type);
2024 Set_Etype (N, Component_Type (Array_Type));
2026 if Present (Index) then
2028 ("too few subscripts in array reference", First (Exprs));
2030 elsif Present (Exp) then
2031 Error_Msg_N ("too many subscripts in array reference", Exp);
2034 end Process_Indexed_Component;
2036 ----------------------------------------
2037 -- Process_Indexed_Component_Or_Slice --
2038 ----------------------------------------
2040 procedure Process_Indexed_Component_Or_Slice is
2042 Exp := First (Exprs);
2043 while Present (Exp) loop
2044 Analyze_Expression (Exp);
2048 Exp := First (Exprs);
2050 -- If one index is present, and it is a subtype name, then the
2051 -- node denotes a slice (note that the case of an explicit range
2052 -- for a slice was already built as an N_Slice node in the first
2053 -- place, so that case is not handled here).
2055 -- We use a replace rather than a rewrite here because this is one
2056 -- of the cases in which the tree built by the parser is plain wrong.
2059 and then Is_Entity_Name (Exp)
2060 and then Is_Type (Entity (Exp))
2063 Make_Slice (Sloc (N),
2065 Discrete_Range => New_Copy (Exp)));
2068 -- Otherwise (more than one index present, or single index is not
2069 -- a subtype name), then we have the indexed component case.
2072 Process_Indexed_Component;
2074 end Process_Indexed_Component_Or_Slice;
2076 ------------------------------------------
2077 -- Process_Overloaded_Indexed_Component --
2078 ------------------------------------------
2080 procedure Process_Overloaded_Indexed_Component is
2089 Set_Etype (N, Any_Type);
2091 Get_First_Interp (P, I, It);
2092 while Present (It.Nam) loop
2095 if Is_Access_Type (Typ) then
2096 Typ := Designated_Type (Typ);
2097 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2100 if Is_Array_Type (Typ) then
2102 -- Got a candidate: verify that index types are compatible
2104 Index := First_Index (Typ);
2106 Exp := First (Exprs);
2107 while Present (Index) and then Present (Exp) loop
2108 if Has_Compatible_Type (Exp, Etype (Index)) then
2120 if Found and then No (Index) and then No (Exp) then
2122 Etype (Component_Type (Typ)),
2123 Etype (Component_Type (Typ)));
2127 Get_Next_Interp (I, It);
2130 if Etype (N) = Any_Type then
2131 Error_Msg_N ("no legal interpretation for indexed component", N);
2132 Set_Is_Overloaded (N, False);
2136 end Process_Overloaded_Indexed_Component;
2138 -- Start of processing for Analyze_Indexed_Component_Form
2141 -- Get name of array, function or type
2145 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement) then
2147 -- If P is an explicit dereference whose prefix is of a
2148 -- remote access-to-subprogram type, then N has already
2149 -- been rewritten as a subprogram call and analyzed.
2154 pragma Assert (Nkind (N) = N_Indexed_Component);
2156 P_T := Base_Type (Etype (P));
2158 if Is_Entity_Name (P) then
2161 if Is_Type (U_N) then
2163 -- Reformat node as a type conversion
2165 E := Remove_Head (Exprs);
2167 if Present (First (Exprs)) then
2169 ("argument of type conversion must be single expression", N);
2172 Change_Node (N, N_Type_Conversion);
2173 Set_Subtype_Mark (N, P);
2175 Set_Expression (N, E);
2177 -- After changing the node, call for the specific Analysis
2178 -- routine directly, to avoid a double call to the expander.
2180 Analyze_Type_Conversion (N);
2184 if Is_Overloadable (U_N) then
2185 Process_Function_Call;
2187 elsif Ekind (Etype (P)) = E_Subprogram_Type
2188 or else (Is_Access_Type (Etype (P))
2190 Ekind (Designated_Type (Etype (P))) =
2193 -- Call to access_to-subprogram with possible implicit dereference
2195 Process_Function_Call;
2197 elsif Is_Generic_Subprogram (U_N) then
2199 -- A common beginner's (or C++ templates fan) error
2201 Error_Msg_N ("generic subprogram cannot be called", N);
2202 Set_Etype (N, Any_Type);
2206 Process_Indexed_Component_Or_Slice;
2209 -- If not an entity name, prefix is an expression that may denote
2210 -- an array or an access-to-subprogram.
2213 if Ekind (P_T) = E_Subprogram_Type
2214 or else (Is_Access_Type (P_T)
2216 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
2218 Process_Function_Call;
2220 elsif Nkind (P) = N_Selected_Component
2221 and then Is_Overloadable (Entity (Selector_Name (P)))
2223 Process_Function_Call;
2226 -- Indexed component, slice, or a call to a member of a family
2227 -- entry, which will be converted to an entry call later.
2229 Process_Indexed_Component_Or_Slice;
2232 end Analyze_Indexed_Component_Form;
2234 ------------------------
2235 -- Analyze_Logical_Op --
2236 ------------------------
2238 procedure Analyze_Logical_Op (N : Node_Id) is
2239 L : constant Node_Id := Left_Opnd (N);
2240 R : constant Node_Id := Right_Opnd (N);
2241 Op_Id : Entity_Id := Entity (N);
2244 Set_Etype (N, Any_Type);
2245 Candidate_Type := Empty;
2247 Analyze_Expression (L);
2248 Analyze_Expression (R);
2250 if Present (Op_Id) then
2252 if Ekind (Op_Id) = E_Operator then
2253 Find_Boolean_Types (L, R, Op_Id, N);
2255 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2259 Op_Id := Get_Name_Entity_Id (Chars (N));
2260 while Present (Op_Id) loop
2261 if Ekind (Op_Id) = E_Operator then
2262 Find_Boolean_Types (L, R, Op_Id, N);
2264 Analyze_User_Defined_Binary_Op (N, Op_Id);
2267 Op_Id := Homonym (Op_Id);
2272 end Analyze_Logical_Op;
2274 ---------------------------
2275 -- Analyze_Membership_Op --
2276 ---------------------------
2278 procedure Analyze_Membership_Op (N : Node_Id) is
2279 Loc : constant Source_Ptr := Sloc (N);
2280 L : constant Node_Id := Left_Opnd (N);
2281 R : constant Node_Id := Right_Opnd (N);
2283 Index : Interp_Index;
2285 Found : Boolean := False;
2289 procedure Try_One_Interp (T1 : Entity_Id);
2290 -- Routine to try one proposed interpretation. Note that the context
2291 -- of the operation plays no role in resolving the arguments, so that
2292 -- if there is more than one interpretation of the operands that is
2293 -- compatible with a membership test, the operation is ambiguous.
2295 --------------------
2296 -- Try_One_Interp --
2297 --------------------
2299 procedure Try_One_Interp (T1 : Entity_Id) is
2301 if Has_Compatible_Type (R, T1) then
2303 and then Base_Type (T1) /= Base_Type (T_F)
2305 It := Disambiguate (L, I_F, Index, Any_Type);
2307 if It = No_Interp then
2308 Ambiguous_Operands (N);
2309 Set_Etype (L, Any_Type);
2326 procedure Analyze_Set_Membership;
2327 -- If a set of alternatives is present, analyze each and find the
2328 -- common type to which they must all resolve.
2330 ----------------------------
2331 -- Analyze_Set_Membership --
2332 ----------------------------
2334 procedure Analyze_Set_Membership is
2336 Index : Interp_Index;
2338 Candidate_Interps : Node_Id;
2339 Common_Type : Entity_Id := Empty;
2343 Candidate_Interps := L;
2345 if not Is_Overloaded (L) then
2346 Common_Type := Etype (L);
2348 Alt := First (Alternatives (N));
2349 while Present (Alt) loop
2352 if not Has_Compatible_Type (Alt, Common_Type) then
2353 Wrong_Type (Alt, Common_Type);
2360 Alt := First (Alternatives (N));
2361 while Present (Alt) loop
2363 if not Is_Overloaded (Alt) then
2364 Common_Type := Etype (Alt);
2367 Get_First_Interp (Alt, Index, It);
2368 while Present (It.Typ) loop
2370 Has_Compatible_Type (Candidate_Interps, It.Typ)
2372 Remove_Interp (Index);
2375 Get_Next_Interp (Index, It);
2378 Get_First_Interp (Alt, Index, It);
2381 Error_Msg_N ("alternative has no legal type", Alt);
2385 -- If alternative is not overloaded, we have a unique type
2388 Set_Etype (Alt, It.Typ);
2389 Get_Next_Interp (Index, It);
2392 Set_Is_Overloaded (Alt, False);
2393 Common_Type := Etype (Alt);
2396 Candidate_Interps := Alt;
2403 Set_Etype (N, Standard_Boolean);
2405 if Present (Common_Type) then
2406 Set_Etype (L, Common_Type);
2407 Set_Is_Overloaded (L, False);
2410 Error_Msg_N ("cannot resolve membership operation", N);
2412 end Analyze_Set_Membership;
2414 -- Start of processing for Analyze_Membership_Op
2417 Analyze_Expression (L);
2420 and then Ada_Version >= Ada_2012
2422 Analyze_Set_Membership;
2426 if Nkind (R) = N_Range
2427 or else (Nkind (R) = N_Attribute_Reference
2428 and then Attribute_Name (R) = Name_Range)
2432 if not Is_Overloaded (L) then
2433 Try_One_Interp (Etype (L));
2436 Get_First_Interp (L, Index, It);
2437 while Present (It.Typ) loop
2438 Try_One_Interp (It.Typ);
2439 Get_Next_Interp (Index, It);
2443 -- If not a range, it can be a subtype mark, or else it is
2444 -- a degenerate membership test with a singleton value, i.e.
2445 -- a test for equality.
2449 if Is_Entity_Name (R)
2450 and then Is_Type (Entity (R))
2453 Check_Fully_Declared (Entity (R), R);
2455 elsif Ada_Version >= Ada_2012 then
2456 if Nkind (N) = N_In then
2472 -- in previous version of the language this is an error
2473 -- that will be diagnosed below.
2479 -- Compatibility between expression and subtype mark or range is
2480 -- checked during resolution. The result of the operation is Boolean
2483 Set_Etype (N, Standard_Boolean);
2485 if Comes_From_Source (N)
2486 and then Present (Right_Opnd (N))
2487 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2489 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2491 end Analyze_Membership_Op;
2493 ----------------------
2494 -- Analyze_Negation --
2495 ----------------------
2497 procedure Analyze_Negation (N : Node_Id) is
2498 R : constant Node_Id := Right_Opnd (N);
2499 Op_Id : Entity_Id := Entity (N);
2502 Set_Etype (N, Any_Type);
2503 Candidate_Type := Empty;
2505 Analyze_Expression (R);
2507 if Present (Op_Id) then
2508 if Ekind (Op_Id) = E_Operator then
2509 Find_Negation_Types (R, Op_Id, N);
2511 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2515 Op_Id := Get_Name_Entity_Id (Chars (N));
2516 while Present (Op_Id) loop
2517 if Ekind (Op_Id) = E_Operator then
2518 Find_Negation_Types (R, Op_Id, N);
2520 Analyze_User_Defined_Unary_Op (N, Op_Id);
2523 Op_Id := Homonym (Op_Id);
2528 end Analyze_Negation;
2534 procedure Analyze_Null (N : Node_Id) is
2536 Set_Etype (N, Any_Access);
2539 ----------------------
2540 -- Analyze_One_Call --
2541 ----------------------
2543 procedure Analyze_One_Call
2547 Success : out Boolean;
2548 Skip_First : Boolean := False)
2550 Actuals : constant List_Id := Parameter_Associations (N);
2551 Prev_T : constant Entity_Id := Etype (N);
2553 Must_Skip : constant Boolean := Skip_First
2554 or else Nkind (Original_Node (N)) = N_Selected_Component
2556 (Nkind (Original_Node (N)) = N_Indexed_Component
2557 and then Nkind (Prefix (Original_Node (N)))
2558 = N_Selected_Component);
2559 -- The first formal must be omitted from the match when trying to find
2560 -- a primitive operation that is a possible interpretation, and also
2561 -- after the call has been rewritten, because the corresponding actual
2562 -- is already known to be compatible, and because this may be an
2563 -- indexing of a call with default parameters.
2567 Is_Indexed : Boolean := False;
2568 Is_Indirect : Boolean := False;
2569 Subp_Type : constant Entity_Id := Etype (Nam);
2572 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2573 -- There may be a user-defined operator that hides the current
2574 -- interpretation. We must check for this independently of the
2575 -- analysis of the call with the user-defined operation, because
2576 -- the parameter names may be wrong and yet the hiding takes place.
2577 -- This fixes a problem with ACATS test B34014O.
2579 -- When the type Address is a visible integer type, and the DEC
2580 -- system extension is visible, the predefined operator may be
2581 -- hidden as well, by one of the address operations in auxdec.
2582 -- Finally, The abstract operations on address do not hide the
2583 -- predefined operator (this is the purpose of making them abstract).
2585 procedure Indicate_Name_And_Type;
2586 -- If candidate interpretation matches, indicate name and type of
2587 -- result on call node.
2589 ----------------------------
2590 -- Indicate_Name_And_Type --
2591 ----------------------------
2593 procedure Indicate_Name_And_Type is
2595 Add_One_Interp (N, Nam, Etype (Nam));
2598 -- If the prefix of the call is a name, indicate the entity
2599 -- being called. If it is not a name, it is an expression that
2600 -- denotes an access to subprogram or else an entry or family. In
2601 -- the latter case, the name is a selected component, and the entity
2602 -- being called is noted on the selector.
2604 if not Is_Type (Nam) then
2605 if Is_Entity_Name (Name (N)) then
2606 Set_Entity (Name (N), Nam);
2608 elsif Nkind (Name (N)) = N_Selected_Component then
2609 Set_Entity (Selector_Name (Name (N)), Nam);
2613 if Debug_Flag_E and not Report then
2614 Write_Str (" Overloaded call ");
2615 Write_Int (Int (N));
2616 Write_Str (" compatible with ");
2617 Write_Int (Int (Nam));
2620 end Indicate_Name_And_Type;
2622 ------------------------
2623 -- Operator_Hidden_By --
2624 ------------------------
2626 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2627 Act1 : constant Node_Id := First_Actual (N);
2628 Act2 : constant Node_Id := Next_Actual (Act1);
2629 Form1 : constant Entity_Id := First_Formal (Fun);
2630 Form2 : constant Entity_Id := Next_Formal (Form1);
2633 if Ekind (Fun) /= E_Function
2634 or else Is_Abstract_Subprogram (Fun)
2638 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2641 elsif Present (Form2) then
2643 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2648 elsif Present (Act2) then
2652 -- Now we know that the arity of the operator matches the function,
2653 -- and the function call is a valid interpretation. The function
2654 -- hides the operator if it has the right signature, or if one of
2655 -- its operands is a non-abstract operation on Address when this is
2656 -- a visible integer type.
2658 return Hides_Op (Fun, Nam)
2659 or else Is_Descendent_Of_Address (Etype (Form1))
2662 and then Is_Descendent_Of_Address (Etype (Form2)));
2663 end Operator_Hidden_By;
2665 -- Start of processing for Analyze_One_Call
2670 -- If the subprogram has no formals or if all the formals have defaults,
2671 -- and the return type is an array type, the node may denote an indexing
2672 -- of the result of a parameterless call. In Ada 2005, the subprogram
2673 -- may have one non-defaulted formal, and the call may have been written
2674 -- in prefix notation, so that the rebuilt parameter list has more than
2677 if not Is_Overloadable (Nam)
2678 and then Ekind (Nam) /= E_Subprogram_Type
2679 and then Ekind (Nam) /= E_Entry_Family
2684 -- An indexing requires at least one actual
2686 if not Is_Empty_List (Actuals)
2688 (Needs_No_Actuals (Nam)
2690 (Needs_One_Actual (Nam)
2691 and then Present (Next_Actual (First (Actuals)))))
2693 if Is_Array_Type (Subp_Type) then
2694 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2696 elsif Is_Access_Type (Subp_Type)
2697 and then Is_Array_Type (Designated_Type (Subp_Type))
2701 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2703 -- The prefix can also be a parameterless function that returns an
2704 -- access to subprogram, in which case this is an indirect call.
2705 -- If this succeeds, an explicit dereference is added later on,
2706 -- in Analyze_Call or Resolve_Call.
2708 elsif Is_Access_Type (Subp_Type)
2709 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2711 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2716 -- If the call has been transformed into a slice, it is of the form
2717 -- F (Subtype) where F is parameterless. The node has been rewritten in
2718 -- Try_Indexed_Call and there is nothing else to do.
2721 and then Nkind (N) = N_Slice
2727 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2731 -- If an indirect call is a possible interpretation, indicate
2732 -- success to the caller.
2738 -- Mismatch in number or names of parameters
2740 elsif Debug_Flag_E then
2741 Write_Str (" normalization fails in call ");
2742 Write_Int (Int (N));
2743 Write_Str (" with subprogram ");
2744 Write_Int (Int (Nam));
2748 -- If the context expects a function call, discard any interpretation
2749 -- that is a procedure. If the node is not overloaded, leave as is for
2750 -- better error reporting when type mismatch is found.
2752 elsif Nkind (N) = N_Function_Call
2753 and then Is_Overloaded (Name (N))
2754 and then Ekind (Nam) = E_Procedure
2758 -- Ditto for function calls in a procedure context
2760 elsif Nkind (N) = N_Procedure_Call_Statement
2761 and then Is_Overloaded (Name (N))
2762 and then Etype (Nam) /= Standard_Void_Type
2766 elsif No (Actuals) then
2768 -- If Normalize succeeds, then there are default parameters for
2771 Indicate_Name_And_Type;
2773 elsif Ekind (Nam) = E_Operator then
2774 if Nkind (N) = N_Procedure_Call_Statement then
2778 -- This can occur when the prefix of the call is an operator
2779 -- name or an expanded name whose selector is an operator name.
2781 Analyze_Operator_Call (N, Nam);
2783 if Etype (N) /= Prev_T then
2785 -- Check that operator is not hidden by a function interpretation
2787 if Is_Overloaded (Name (N)) then
2793 Get_First_Interp (Name (N), I, It);
2794 while Present (It.Nam) loop
2795 if Operator_Hidden_By (It.Nam) then
2796 Set_Etype (N, Prev_T);
2800 Get_Next_Interp (I, It);
2805 -- If operator matches formals, record its name on the call.
2806 -- If the operator is overloaded, Resolve will select the
2807 -- correct one from the list of interpretations. The call
2808 -- node itself carries the first candidate.
2810 Set_Entity (Name (N), Nam);
2813 elsif Report and then Etype (N) = Any_Type then
2814 Error_Msg_N ("incompatible arguments for operator", N);
2818 -- Normalize_Actuals has chained the named associations in the
2819 -- correct order of the formals.
2821 Actual := First_Actual (N);
2822 Formal := First_Formal (Nam);
2824 -- If we are analyzing a call rewritten from object notation,
2825 -- skip first actual, which may be rewritten later as an
2826 -- explicit dereference.
2829 Next_Actual (Actual);
2830 Next_Formal (Formal);
2833 while Present (Actual) and then Present (Formal) loop
2834 if Nkind (Parent (Actual)) /= N_Parameter_Association
2835 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2837 -- The actual can be compatible with the formal, but we must
2838 -- also check that the context is not an address type that is
2839 -- visibly an integer type, as is the case in VMS_64. In this
2840 -- case the use of literals is illegal, except in the body of
2841 -- descendents of system, where arithmetic operations on
2842 -- address are of course used.
2844 if Has_Compatible_Type (Actual, Etype (Formal))
2846 (Etype (Actual) /= Universal_Integer
2847 or else not Is_Descendent_Of_Address (Etype (Formal))
2849 Is_Predefined_File_Name
2850 (Unit_File_Name (Get_Source_Unit (N))))
2852 Next_Actual (Actual);
2853 Next_Formal (Formal);
2856 if Debug_Flag_E then
2857 Write_Str (" type checking fails in call ");
2858 Write_Int (Int (N));
2859 Write_Str (" with formal ");
2860 Write_Int (Int (Formal));
2861 Write_Str (" in subprogram ");
2862 Write_Int (Int (Nam));
2866 if Report and not Is_Indexed and not Is_Indirect then
2868 -- Ada 2005 (AI-251): Complete the error notification
2869 -- to help new Ada 2005 users.
2871 if Is_Class_Wide_Type (Etype (Formal))
2872 and then Is_Interface (Etype (Etype (Formal)))
2873 and then not Interface_Present_In_Ancestor
2874 (Typ => Etype (Actual),
2875 Iface => Etype (Etype (Formal)))
2878 ("(Ada 2005) does not implement interface }",
2879 Actual, Etype (Etype (Formal)));
2882 Wrong_Type (Actual, Etype (Formal));
2884 if Nkind (Actual) = N_Op_Eq
2885 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2887 Formal := First_Formal (Nam);
2888 while Present (Formal) loop
2889 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2890 Error_Msg_N -- CODEFIX
2891 ("possible misspelling of `='>`!", Actual);
2895 Next_Formal (Formal);
2899 if All_Errors_Mode then
2900 Error_Msg_Sloc := Sloc (Nam);
2902 if Etype (Formal) = Any_Type then
2904 ("there is no legal actual parameter", Actual);
2907 if Is_Overloadable (Nam)
2908 and then Present (Alias (Nam))
2909 and then not Comes_From_Source (Nam)
2912 ("\\ =='> in call to inherited operation & #!",
2915 elsif Ekind (Nam) = E_Subprogram_Type then
2917 Access_To_Subprogram_Typ :
2918 constant Entity_Id :=
2920 (Associated_Node_For_Itype (Nam));
2923 "\\ =='> in call to dereference of &#!",
2924 Actual, Access_To_Subprogram_Typ);
2929 ("\\ =='> in call to &#!", Actual, Nam);
2939 -- Normalize_Actuals has verified that a default value exists
2940 -- for this formal. Current actual names a subsequent formal.
2942 Next_Formal (Formal);
2946 -- On exit, all actuals match
2948 Indicate_Name_And_Type;
2950 end Analyze_One_Call;
2952 ---------------------------
2953 -- Analyze_Operator_Call --
2954 ---------------------------
2956 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2957 Op_Name : constant Name_Id := Chars (Op_Id);
2958 Act1 : constant Node_Id := First_Actual (N);
2959 Act2 : constant Node_Id := Next_Actual (Act1);
2962 -- Binary operator case
2964 if Present (Act2) then
2966 -- If more than two operands, then not binary operator after all
2968 if Present (Next_Actual (Act2)) then
2971 elsif Op_Name = Name_Op_Add
2972 or else Op_Name = Name_Op_Subtract
2973 or else Op_Name = Name_Op_Multiply
2974 or else Op_Name = Name_Op_Divide
2975 or else Op_Name = Name_Op_Mod
2976 or else Op_Name = Name_Op_Rem
2977 or else Op_Name = Name_Op_Expon
2979 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2981 elsif Op_Name = Name_Op_And
2982 or else Op_Name = Name_Op_Or
2983 or else Op_Name = Name_Op_Xor
2985 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2987 elsif Op_Name = Name_Op_Lt
2988 or else Op_Name = Name_Op_Le
2989 or else Op_Name = Name_Op_Gt
2990 or else Op_Name = Name_Op_Ge
2992 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2994 elsif Op_Name = Name_Op_Eq
2995 or else Op_Name = Name_Op_Ne
2997 Find_Equality_Types (Act1, Act2, Op_Id, N);
2999 elsif Op_Name = Name_Op_Concat then
3000 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
3002 -- Is this else null correct, or should it be an abort???
3008 -- Unary operator case
3011 if Op_Name = Name_Op_Subtract or else
3012 Op_Name = Name_Op_Add or else
3013 Op_Name = Name_Op_Abs
3015 Find_Unary_Types (Act1, Op_Id, N);
3018 Op_Name = Name_Op_Not
3020 Find_Negation_Types (Act1, Op_Id, N);
3022 -- Is this else null correct, or should it be an abort???
3028 end Analyze_Operator_Call;
3030 -------------------------------------------
3031 -- Analyze_Overloaded_Selected_Component --
3032 -------------------------------------------
3034 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
3035 Nam : constant Node_Id := Prefix (N);
3036 Sel : constant Node_Id := Selector_Name (N);
3043 Set_Etype (Sel, Any_Type);
3045 Get_First_Interp (Nam, I, It);
3046 while Present (It.Typ) loop
3047 if Is_Access_Type (It.Typ) then
3048 T := Designated_Type (It.Typ);
3049 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3054 if Is_Record_Type (T) then
3056 -- If the prefix is a class-wide type, the visible components are
3057 -- those of the base type.
3059 if Is_Class_Wide_Type (T) then
3063 Comp := First_Entity (T);
3064 while Present (Comp) loop
3065 if Chars (Comp) = Chars (Sel)
3066 and then Is_Visible_Component (Comp)
3069 -- AI05-105: if the context is an object renaming with
3070 -- an anonymous access type, the expected type of the
3071 -- object must be anonymous. This is a name resolution rule.
3073 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
3074 or else No (Access_Definition (Parent (N)))
3075 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
3077 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
3079 Set_Entity (Sel, Comp);
3080 Set_Etype (Sel, Etype (Comp));
3081 Add_One_Interp (N, Etype (Comp), Etype (Comp));
3083 -- This also specifies a candidate to resolve the name.
3084 -- Further overloading will be resolved from context.
3085 -- The selector name itself does not carry overloading
3088 Set_Etype (Nam, It.Typ);
3091 -- Named access type in the context of a renaming
3092 -- declaration with an access definition. Remove
3093 -- inapplicable candidate.
3102 elsif Is_Concurrent_Type (T) then
3103 Comp := First_Entity (T);
3104 while Present (Comp)
3105 and then Comp /= First_Private_Entity (T)
3107 if Chars (Comp) = Chars (Sel) then
3108 if Is_Overloadable (Comp) then
3109 Add_One_Interp (Sel, Comp, Etype (Comp));
3111 Set_Entity_With_Style_Check (Sel, Comp);
3112 Generate_Reference (Comp, Sel);
3115 Set_Etype (Sel, Etype (Comp));
3116 Set_Etype (N, Etype (Comp));
3117 Set_Etype (Nam, It.Typ);
3119 -- For access type case, introduce explicit dereference for
3120 -- more uniform treatment of entry calls. Do this only once
3121 -- if several interpretations yield an access type.
3123 if Is_Access_Type (Etype (Nam))
3124 and then Nkind (Nam) /= N_Explicit_Dereference
3126 Insert_Explicit_Dereference (Nam);
3128 (Warn_On_Dereference, "?implicit dereference", N);
3135 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3138 Get_Next_Interp (I, It);
3141 if Etype (N) = Any_Type
3142 and then not Try_Object_Operation (N)
3144 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
3145 Set_Entity (Sel, Any_Id);
3146 Set_Etype (Sel, Any_Type);
3148 end Analyze_Overloaded_Selected_Component;
3150 ----------------------------------
3151 -- Analyze_Qualified_Expression --
3152 ----------------------------------
3154 procedure Analyze_Qualified_Expression (N : Node_Id) is
3155 Mark : constant Entity_Id := Subtype_Mark (N);
3156 Expr : constant Node_Id := Expression (N);
3162 Analyze_Expression (Expr);
3164 Set_Etype (N, Any_Type);
3169 if T = Any_Type then
3173 Check_Fully_Declared (T, N);
3175 -- If expected type is class-wide, check for exact match before
3176 -- expansion, because if the expression is a dispatching call it
3177 -- may be rewritten as explicit dereference with class-wide result.
3178 -- If expression is overloaded, retain only interpretations that
3179 -- will yield exact matches.
3181 if Is_Class_Wide_Type (T) then
3182 if not Is_Overloaded (Expr) then
3183 if Base_Type (Etype (Expr)) /= Base_Type (T) then
3184 if Nkind (Expr) = N_Aggregate then
3185 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
3187 Wrong_Type (Expr, T);
3192 Get_First_Interp (Expr, I, It);
3194 while Present (It.Nam) loop
3195 if Base_Type (It.Typ) /= Base_Type (T) then
3199 Get_Next_Interp (I, It);
3205 end Analyze_Qualified_Expression;
3207 -----------------------------------
3208 -- Analyze_Quantified_Expression --
3209 -----------------------------------
3211 procedure Analyze_Quantified_Expression (N : Node_Id) is
3212 Loc : constant Source_Ptr := Sloc (N);
3213 Ent : constant Entity_Id :=
3215 (E_Loop, Current_Scope, Sloc (N), 'L');
3220 Set_Etype (Ent, Standard_Void_Type);
3221 Set_Parent (Ent, N);
3223 if Present (Loop_Parameter_Specification (N)) then
3225 Make_Iteration_Scheme (Loc,
3226 Loop_Parameter_Specification =>
3227 Loop_Parameter_Specification (N));
3230 Make_Iteration_Scheme (Loc,
3231 Iterator_Specification =>
3232 Iterator_Specification (N));
3236 Set_Parent (Iterator, N);
3237 Analyze_Iteration_Scheme (Iterator);
3239 -- The loop specification may have been converted into an
3240 -- iterator specification during its analysis. Update the
3241 -- quantified node accordingly.
3243 if Present (Iterator_Specification (Iterator)) then
3244 Set_Iterator_Specification
3245 (N, Iterator_Specification (Iterator));
3246 Set_Loop_Parameter_Specification (N, Empty);
3249 Analyze (Condition (N));
3252 Set_Etype (N, Standard_Boolean);
3253 end Analyze_Quantified_Expression;
3259 procedure Analyze_Range (N : Node_Id) is
3260 L : constant Node_Id := Low_Bound (N);
3261 H : constant Node_Id := High_Bound (N);
3262 I1, I2 : Interp_Index;
3265 procedure Check_Common_Type (T1, T2 : Entity_Id);
3266 -- Verify the compatibility of two types, and choose the
3267 -- non universal one if the other is universal.
3269 procedure Check_High_Bound (T : Entity_Id);
3270 -- Test one interpretation of the low bound against all those
3271 -- of the high bound.
3273 procedure Check_Universal_Expression (N : Node_Id);
3274 -- In Ada83, reject bounds of a universal range that are not
3275 -- literals or entity names.
3277 -----------------------
3278 -- Check_Common_Type --
3279 -----------------------
3281 procedure Check_Common_Type (T1, T2 : Entity_Id) is
3283 if Covers (T1 => T1, T2 => T2)
3285 Covers (T1 => T2, T2 => T1)
3287 if T1 = Universal_Integer
3288 or else T1 = Universal_Real
3289 or else T1 = Any_Character
3291 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
3294 Add_One_Interp (N, T1, T1);
3297 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
3300 end Check_Common_Type;
3302 ----------------------
3303 -- Check_High_Bound --
3304 ----------------------
3306 procedure Check_High_Bound (T : Entity_Id) is
3308 if not Is_Overloaded (H) then
3309 Check_Common_Type (T, Etype (H));
3311 Get_First_Interp (H, I2, It2);
3312 while Present (It2.Typ) loop
3313 Check_Common_Type (T, It2.Typ);
3314 Get_Next_Interp (I2, It2);
3317 end Check_High_Bound;
3319 -----------------------------
3320 -- Is_Universal_Expression --
3321 -----------------------------
3323 procedure Check_Universal_Expression (N : Node_Id) is
3325 if Etype (N) = Universal_Integer
3326 and then Nkind (N) /= N_Integer_Literal
3327 and then not Is_Entity_Name (N)
3328 and then Nkind (N) /= N_Attribute_Reference
3330 Error_Msg_N ("illegal bound in discrete range", N);
3332 end Check_Universal_Expression;
3334 -- Start of processing for Analyze_Range
3337 Set_Etype (N, Any_Type);
3338 Analyze_Expression (L);
3339 Analyze_Expression (H);
3341 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
3345 if not Is_Overloaded (L) then
3346 Check_High_Bound (Etype (L));
3348 Get_First_Interp (L, I1, It1);
3349 while Present (It1.Typ) loop
3350 Check_High_Bound (It1.Typ);
3351 Get_Next_Interp (I1, It1);
3355 -- If result is Any_Type, then we did not find a compatible pair
3357 if Etype (N) = Any_Type then
3358 Error_Msg_N ("incompatible types in range ", N);
3362 if Ada_Version = Ada_83
3364 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
3365 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
3367 Check_Universal_Expression (L);
3368 Check_Universal_Expression (H);
3372 -----------------------
3373 -- Analyze_Reference --
3374 -----------------------
3376 procedure Analyze_Reference (N : Node_Id) is
3377 P : constant Node_Id := Prefix (N);
3380 Acc_Type : Entity_Id;
3385 -- An interesting error check, if we take the 'Reference of an object
3386 -- for which a pragma Atomic or Volatile has been given, and the type
3387 -- of the object is not Atomic or Volatile, then we are in trouble. The
3388 -- problem is that no trace of the atomic/volatile status will remain
3389 -- for the backend to respect when it deals with the resulting pointer,
3390 -- since the pointer type will not be marked atomic (it is a pointer to
3391 -- the base type of the object).
3393 -- It is not clear if that can ever occur, but in case it does, we will
3394 -- generate an error message. Not clear if this message can ever be
3395 -- generated, and pretty clear that it represents a bug if it is, still
3396 -- seems worth checking, except in CodePeer mode where we do not really
3397 -- care and don't want to bother the user.
3401 if Is_Entity_Name (P)
3402 and then Is_Object_Reference (P)
3403 and then not CodePeer_Mode
3408 if (Has_Atomic_Components (E)
3409 and then not Has_Atomic_Components (T))
3411 (Has_Volatile_Components (E)
3412 and then not Has_Volatile_Components (T))
3413 or else (Is_Atomic (E) and then not Is_Atomic (T))
3414 or else (Is_Volatile (E) and then not Is_Volatile (T))
3416 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
3420 -- Carry on with normal processing
3422 Acc_Type := Create_Itype (E_Allocator_Type, N);
3423 Set_Etype (Acc_Type, Acc_Type);
3424 Set_Directly_Designated_Type (Acc_Type, Etype (P));
3425 Set_Etype (N, Acc_Type);
3426 end Analyze_Reference;
3428 --------------------------------
3429 -- Analyze_Selected_Component --
3430 --------------------------------
3432 -- Prefix is a record type or a task or protected type. In the latter case,
3433 -- the selector must denote a visible entry.
3435 procedure Analyze_Selected_Component (N : Node_Id) is
3436 Name : constant Node_Id := Prefix (N);
3437 Sel : constant Node_Id := Selector_Name (N);
3440 Has_Candidate : Boolean := False;
3443 Pent : Entity_Id := Empty;
3444 Prefix_Type : Entity_Id;
3446 Type_To_Use : Entity_Id;
3447 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
3448 -- a class-wide type, we use its root type, whose components are
3449 -- present in the class-wide type.
3451 Is_Single_Concurrent_Object : Boolean;
3452 -- Set True if the prefix is a single task or a single protected object
3454 procedure Find_Component_In_Instance (Rec : Entity_Id);
3455 -- In an instance, a component of a private extension may not be visible
3456 -- while it was visible in the generic. Search candidate scope for a
3457 -- component with the proper identifier. This is only done if all other
3458 -- searches have failed. When the match is found (it always will be),
3459 -- the Etype of both N and Sel are set from this component, and the
3460 -- entity of Sel is set to reference this component.
3462 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
3463 -- It is known that the parent of N denotes a subprogram call. Comp
3464 -- is an overloadable component of the concurrent type of the prefix.
3465 -- Determine whether all formals of the parent of N and Comp are mode
3466 -- conformant. If the parent node is not analyzed yet it may be an
3467 -- indexed component rather than a function call.
3469 --------------------------------
3470 -- Find_Component_In_Instance --
3471 --------------------------------
3473 procedure Find_Component_In_Instance (Rec : Entity_Id) is
3477 Comp := First_Component (Rec);
3478 while Present (Comp) loop
3479 if Chars (Comp) = Chars (Sel) then
3480 Set_Entity_With_Style_Check (Sel, Comp);
3481 Set_Etype (Sel, Etype (Comp));
3482 Set_Etype (N, Etype (Comp));
3486 Next_Component (Comp);
3489 -- This must succeed because code was legal in the generic
3491 raise Program_Error;
3492 end Find_Component_In_Instance;
3494 ------------------------------
3495 -- Has_Mode_Conformant_Spec --
3496 ------------------------------
3498 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
3499 Comp_Param : Entity_Id;
3501 Param_Typ : Entity_Id;
3504 Comp_Param := First_Formal (Comp);
3506 if Nkind (Parent (N)) = N_Indexed_Component then
3507 Param := First (Expressions (Parent (N)));
3509 Param := First (Parameter_Associations (Parent (N)));
3512 while Present (Comp_Param)
3513 and then Present (Param)
3515 Param_Typ := Find_Parameter_Type (Param);
3517 if Present (Param_Typ)
3519 not Conforming_Types
3520 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3525 Next_Formal (Comp_Param);
3529 -- One of the specs has additional formals
3531 if Present (Comp_Param) or else Present (Param) then
3536 end Has_Mode_Conformant_Spec;
3538 -- Start of processing for Analyze_Selected_Component
3541 Set_Etype (N, Any_Type);
3543 if Is_Overloaded (Name) then
3544 Analyze_Overloaded_Selected_Component (N);
3547 elsif Etype (Name) = Any_Type then
3548 Set_Entity (Sel, Any_Id);
3549 Set_Etype (Sel, Any_Type);
3553 Prefix_Type := Etype (Name);
3556 if Is_Access_Type (Prefix_Type) then
3558 -- A RACW object can never be used as prefix of a selected component
3559 -- since that means it is dereferenced without being a controlling
3560 -- operand of a dispatching operation (RM E.2.2(16/1)). Before
3561 -- reporting an error, we must check whether this is actually a
3562 -- dispatching call in prefix form.
3564 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3565 and then Comes_From_Source (N)
3567 if Try_Object_Operation (N) then
3571 ("invalid dereference of a remote access-to-class-wide value",
3575 -- Normal case of selected component applied to access type
3578 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3580 if Is_Entity_Name (Name) then
3581 Pent := Entity (Name);
3582 elsif Nkind (Name) = N_Selected_Component
3583 and then Is_Entity_Name (Selector_Name (Name))
3585 Pent := Entity (Selector_Name (Name));
3588 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3591 -- If we have an explicit dereference of a remote access-to-class-wide
3592 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3593 -- have to check for the case of a prefix that is a controlling operand
3594 -- of a prefixed dispatching call, as the dereference is legal in that
3595 -- case. Normally this condition is checked in Validate_Remote_Access_
3596 -- To_Class_Wide_Type, but we have to defer the checking for selected
3597 -- component prefixes because of the prefixed dispatching call case.
3598 -- Note that implicit dereferences are checked for this just above.
3600 elsif Nkind (Name) = N_Explicit_Dereference
3601 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3602 and then Comes_From_Source (N)
3604 if Try_Object_Operation (N) then
3608 ("invalid dereference of a remote access-to-class-wide value",
3613 -- (Ada 2005): if the prefix is the limited view of a type, and
3614 -- the context already includes the full view, use the full view
3615 -- in what follows, either to retrieve a component of to find
3616 -- a primitive operation. If the prefix is an explicit dereference,
3617 -- set the type of the prefix to reflect this transformation.
3618 -- If the non-limited view is itself an incomplete type, get the
3619 -- full view if available.
3621 if Is_Incomplete_Type (Prefix_Type)
3622 and then From_With_Type (Prefix_Type)
3623 and then Present (Non_Limited_View (Prefix_Type))
3625 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3627 if Nkind (N) = N_Explicit_Dereference then
3628 Set_Etype (Prefix (N), Prefix_Type);
3631 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3632 and then From_With_Type (Prefix_Type)
3633 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3636 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3638 if Nkind (N) = N_Explicit_Dereference then
3639 Set_Etype (Prefix (N), Prefix_Type);
3643 if Ekind (Prefix_Type) = E_Private_Subtype then
3644 Prefix_Type := Base_Type (Prefix_Type);
3647 Type_To_Use := Prefix_Type;
3649 -- For class-wide types, use the entity list of the root type. This
3650 -- indirection is specially important for private extensions because
3651 -- only the root type get switched (not the class-wide type).
3653 if Is_Class_Wide_Type (Prefix_Type) then
3654 Type_To_Use := Root_Type (Prefix_Type);
3657 -- If the prefix is a single concurrent object, use its name in error
3658 -- messages, rather than that of its anonymous type.
3660 Is_Single_Concurrent_Object :=
3661 Is_Concurrent_Type (Prefix_Type)
3662 and then Is_Internal_Name (Chars (Prefix_Type))
3663 and then not Is_Derived_Type (Prefix_Type)
3664 and then Is_Entity_Name (Name);
3666 Comp := First_Entity (Type_To_Use);
3668 -- If the selector has an original discriminant, the node appears in
3669 -- an instance. Replace the discriminant with the corresponding one
3670 -- in the current discriminated type. For nested generics, this must
3671 -- be done transitively, so note the new original discriminant.
3673 if Nkind (Sel) = N_Identifier
3674 and then Present (Original_Discriminant (Sel))
3676 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3678 -- Mark entity before rewriting, for completeness and because
3679 -- subsequent semantic checks might examine the original node.
3681 Set_Entity (Sel, Comp);
3682 Rewrite (Selector_Name (N),
3683 New_Occurrence_Of (Comp, Sloc (N)));
3684 Set_Original_Discriminant (Selector_Name (N), Comp);
3685 Set_Etype (N, Etype (Comp));
3687 if Is_Access_Type (Etype (Name)) then
3688 Insert_Explicit_Dereference (Name);
3689 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3692 elsif Is_Record_Type (Prefix_Type) then
3694 -- Find component with given name
3696 while Present (Comp) loop
3697 if Chars (Comp) = Chars (Sel)
3698 and then Is_Visible_Component (Comp)
3700 Set_Entity_With_Style_Check (Sel, Comp);
3701 Set_Etype (Sel, Etype (Comp));
3703 if Ekind (Comp) = E_Discriminant then
3704 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3706 ("cannot reference discriminant of Unchecked_Union",
3710 if Is_Generic_Type (Prefix_Type)
3712 Is_Generic_Type (Root_Type (Prefix_Type))
3714 Set_Original_Discriminant (Sel, Comp);
3718 -- Resolve the prefix early otherwise it is not possible to
3719 -- build the actual subtype of the component: it may need
3720 -- to duplicate this prefix and duplication is only allowed
3721 -- on fully resolved expressions.
3725 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3726 -- subtypes in a package specification.
3729 -- limited with Pkg;
3731 -- type Acc_Inc is access Pkg.T;
3733 -- N : Natural := X.all.Comp; -- ERROR, limited view
3734 -- end Pkg; -- Comp is not visible
3736 if Nkind (Name) = N_Explicit_Dereference
3737 and then From_With_Type (Etype (Prefix (Name)))
3738 and then not Is_Potentially_Use_Visible (Etype (Name))
3739 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3740 N_Package_Specification
3743 ("premature usage of incomplete}", Prefix (Name),
3744 Etype (Prefix (Name)));
3747 -- We never need an actual subtype for the case of a selection
3748 -- for a indexed component of a non-packed array, since in
3749 -- this case gigi generates all the checks and can find the
3750 -- necessary bounds information.
3752 -- We also do not need an actual subtype for the case of a
3753 -- first, last, length, or range attribute applied to a
3754 -- non-packed array, since gigi can again get the bounds in
3755 -- these cases (gigi cannot handle the packed case, since it
3756 -- has the bounds of the packed array type, not the original
3757 -- bounds of the type). However, if the prefix is itself a
3758 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3759 -- as a dynamic-sized temporary, so we do generate an actual
3760 -- subtype for this case.
3762 Parent_N := Parent (N);
3764 if not Is_Packed (Etype (Comp))
3766 ((Nkind (Parent_N) = N_Indexed_Component
3767 and then Nkind (Name) /= N_Selected_Component)
3769 (Nkind (Parent_N) = N_Attribute_Reference
3770 and then (Attribute_Name (Parent_N) = Name_First
3772 Attribute_Name (Parent_N) = Name_Last
3774 Attribute_Name (Parent_N) = Name_Length
3776 Attribute_Name (Parent_N) = Name_Range)))
3778 Set_Etype (N, Etype (Comp));
3780 -- If full analysis is not enabled, we do not generate an
3781 -- actual subtype, because in the absence of expansion
3782 -- reference to a formal of a protected type, for example,
3783 -- will not be properly transformed, and will lead to
3784 -- out-of-scope references in gigi.
3786 -- In all other cases, we currently build an actual subtype.
3787 -- It seems likely that many of these cases can be avoided,
3788 -- but right now, the front end makes direct references to the
3789 -- bounds (e.g. in generating a length check), and if we do
3790 -- not make an actual subtype, we end up getting a direct
3791 -- reference to a discriminant, which will not do.
3793 elsif Full_Analysis then
3795 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3796 Insert_Action (N, Act_Decl);
3798 if No (Act_Decl) then
3799 Set_Etype (N, Etype (Comp));
3802 -- Component type depends on discriminants. Enter the
3803 -- main attributes of the subtype.
3806 Subt : constant Entity_Id :=
3807 Defining_Identifier (Act_Decl);
3810 Set_Etype (Subt, Base_Type (Etype (Comp)));
3811 Set_Ekind (Subt, Ekind (Etype (Comp)));
3812 Set_Etype (N, Subt);
3816 -- If Full_Analysis not enabled, just set the Etype
3819 Set_Etype (N, Etype (Comp));
3825 -- If the prefix is a private extension, check only the visible
3826 -- components of the partial view. This must include the tag,
3827 -- which can appear in expanded code in a tag check.
3829 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3830 and then Chars (Selector_Name (N)) /= Name_uTag
3832 exit when Comp = Last_Entity (Type_To_Use);
3838 -- Ada 2005 (AI-252): The selected component can be interpreted as
3839 -- a prefixed view of a subprogram. Depending on the context, this is
3840 -- either a name that can appear in a renaming declaration, or part
3841 -- of an enclosing call given in prefix form.
3843 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3844 -- selected component should resolve to a name.
3846 if Ada_Version >= Ada_2005
3847 and then Is_Tagged_Type (Prefix_Type)
3848 and then not Is_Concurrent_Type (Prefix_Type)
3850 if Nkind (Parent (N)) = N_Generic_Association
3851 or else Nkind (Parent (N)) = N_Requeue_Statement
3852 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3854 if Find_Primitive_Operation (N) then
3858 elsif Try_Object_Operation (N) then
3862 -- If the transformation fails, it will be necessary to redo the
3863 -- analysis with all errors enabled, to indicate candidate
3864 -- interpretations and reasons for each failure ???
3868 elsif Is_Private_Type (Prefix_Type) then
3870 -- Allow access only to discriminants of the type. If the type has
3871 -- no full view, gigi uses the parent type for the components, so we
3872 -- do the same here.
3874 if No (Full_View (Prefix_Type)) then
3875 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3876 Comp := First_Entity (Type_To_Use);
3879 while Present (Comp) loop
3880 if Chars (Comp) = Chars (Sel) then
3881 if Ekind (Comp) = E_Discriminant then
3882 Set_Entity_With_Style_Check (Sel, Comp);
3883 Generate_Reference (Comp, Sel);
3885 Set_Etype (Sel, Etype (Comp));
3886 Set_Etype (N, Etype (Comp));
3888 if Is_Generic_Type (Prefix_Type)
3889 or else Is_Generic_Type (Root_Type (Prefix_Type))
3891 Set_Original_Discriminant (Sel, Comp);
3894 -- Before declaring an error, check whether this is tagged
3895 -- private type and a call to a primitive operation.
3897 elsif Ada_Version >= Ada_2005
3898 and then Is_Tagged_Type (Prefix_Type)
3899 and then Try_Object_Operation (N)
3904 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3905 Error_Msg_NE ("invisible selector& for }", N, Sel);
3906 Set_Entity (Sel, Any_Id);
3907 Set_Etype (N, Any_Type);
3916 elsif Is_Concurrent_Type (Prefix_Type) then
3918 -- Find visible operation with given name. For a protected type,
3919 -- the possible candidates are discriminants, entries or protected
3920 -- procedures. For a task type, the set can only include entries or
3921 -- discriminants if the task type is not an enclosing scope. If it
3922 -- is an enclosing scope (e.g. in an inner task) then all entities
3923 -- are visible, but the prefix must denote the enclosing scope, i.e.
3924 -- can only be a direct name or an expanded name.
3926 Set_Etype (Sel, Any_Type);
3927 In_Scope := In_Open_Scopes (Prefix_Type);
3929 while Present (Comp) loop
3930 if Chars (Comp) = Chars (Sel) then
3931 if Is_Overloadable (Comp) then
3932 Add_One_Interp (Sel, Comp, Etype (Comp));
3934 -- If the prefix is tagged, the correct interpretation may
3935 -- lie in the primitive or class-wide operations of the
3936 -- type. Perform a simple conformance check to determine
3937 -- whether Try_Object_Operation should be invoked even if
3938 -- a visible entity is found.
3940 if Is_Tagged_Type (Prefix_Type)
3942 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3944 N_Indexed_Component)
3945 and then Has_Mode_Conformant_Spec (Comp)
3947 Has_Candidate := True;
3950 -- Note: a selected component may not denote a component of a
3951 -- protected type (4.1.3(7)).
3953 elsif Ekind_In (Comp, E_Discriminant, E_Entry_Family)
3955 and then not Is_Protected_Type (Prefix_Type)
3956 and then Is_Entity_Name (Name))
3958 Set_Entity_With_Style_Check (Sel, Comp);
3959 Generate_Reference (Comp, Sel);
3965 Set_Etype (Sel, Etype (Comp));
3966 Set_Etype (N, Etype (Comp));
3968 if Ekind (Comp) = E_Discriminant then
3969 Set_Original_Discriminant (Sel, Comp);
3972 -- For access type case, introduce explicit dereference for
3973 -- more uniform treatment of entry calls.
3975 if Is_Access_Type (Etype (Name)) then
3976 Insert_Explicit_Dereference (Name);
3978 (Warn_On_Dereference, "?implicit dereference", N);
3984 exit when not In_Scope
3986 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3989 -- If there is no visible entity with the given name or none of the
3990 -- visible entities are plausible interpretations, check whether
3991 -- there is some other primitive operation with that name.
3993 if Ada_Version >= Ada_2005
3994 and then Is_Tagged_Type (Prefix_Type)
3996 if (Etype (N) = Any_Type
3997 or else not Has_Candidate)
3998 and then Try_Object_Operation (N)
4002 -- If the context is not syntactically a procedure call, it
4003 -- may be a call to a primitive function declared outside of
4004 -- the synchronized type.
4006 -- If the context is a procedure call, there might still be
4007 -- an overloading between an entry and a primitive procedure
4008 -- declared outside of the synchronized type, called in prefix
4009 -- notation. This is harder to disambiguate because in one case
4010 -- the controlling formal is implicit ???
4012 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
4013 and then Nkind (Parent (N)) /= N_Indexed_Component
4014 and then Try_Object_Operation (N)
4020 if Etype (N) = Any_Type and then Is_Protected_Type (Prefix_Type) then
4021 -- Case of a prefix of a protected type: selector might denote
4022 -- an invisible private component.
4024 Comp := First_Private_Entity (Base_Type (Prefix_Type));
4025 while Present (Comp) and then Chars (Comp) /= Chars (Sel) loop
4029 if Present (Comp) then
4030 if Is_Single_Concurrent_Object then
4031 Error_Msg_Node_2 := Entity (Name);
4032 Error_Msg_NE ("invisible selector& for &", N, Sel);
4035 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4036 Error_Msg_NE ("invisible selector& for }", N, Sel);
4042 Set_Is_Overloaded (N, Is_Overloaded (Sel));
4047 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
4050 -- If N still has no type, the component is not defined in the prefix
4052 if Etype (N) = Any_Type then
4054 if Is_Single_Concurrent_Object then
4055 Error_Msg_Node_2 := Entity (Name);
4056 Error_Msg_NE ("no selector& for&", N, Sel);
4058 Check_Misspelled_Selector (Type_To_Use, Sel);
4060 elsif Is_Generic_Type (Prefix_Type)
4061 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
4062 and then Prefix_Type /= Etype (Prefix_Type)
4063 and then Is_Record_Type (Etype (Prefix_Type))
4065 -- If this is a derived formal type, the parent may have
4066 -- different visibility at this point. Try for an inherited
4067 -- component before reporting an error.
4069 Set_Etype (Prefix (N), Etype (Prefix_Type));
4070 Analyze_Selected_Component (N);
4073 -- Similarly, if this is the actual for a formal derived type, the
4074 -- component inherited from the generic parent may not be visible
4075 -- in the actual, but the selected component is legal.
4077 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
4078 and then Is_Generic_Actual_Type (Prefix_Type)
4079 and then Present (Full_View (Prefix_Type))
4082 Find_Component_In_Instance
4083 (Generic_Parent_Type (Parent (Prefix_Type)));
4086 -- Finally, the formal and the actual may be private extensions,
4087 -- but the generic is declared in a child unit of the parent, and
4088 -- an addtional step is needed to retrieve the proper scope.
4091 and then Present (Parent_Subtype (Etype (Base_Type (Prefix_Type))))
4093 Find_Component_In_Instance
4094 (Parent_Subtype (Etype (Base_Type (Prefix_Type))));
4097 -- Component not found, specialize error message when appropriate
4100 if Ekind (Prefix_Type) = E_Record_Subtype then
4102 -- Check whether this is a component of the base type which
4103 -- is absent from a statically constrained subtype. This will
4104 -- raise constraint error at run time, but is not a compile-
4105 -- time error. When the selector is illegal for base type as
4106 -- well fall through and generate a compilation error anyway.
4108 Comp := First_Component (Base_Type (Prefix_Type));
4109 while Present (Comp) loop
4110 if Chars (Comp) = Chars (Sel)
4111 and then Is_Visible_Component (Comp)
4113 Set_Entity_With_Style_Check (Sel, Comp);
4114 Generate_Reference (Comp, Sel);
4115 Set_Etype (Sel, Etype (Comp));
4116 Set_Etype (N, Etype (Comp));
4118 -- Emit appropriate message. Gigi will replace the
4119 -- node subsequently with the appropriate Raise.
4121 Apply_Compile_Time_Constraint_Error
4122 (N, "component not present in }?",
4123 CE_Discriminant_Check_Failed,
4124 Ent => Prefix_Type, Rep => False);
4125 Set_Raises_Constraint_Error (N);
4129 Next_Component (Comp);
4134 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4135 Error_Msg_NE ("no selector& for}", N, Sel);
4137 Check_Misspelled_Selector (Type_To_Use, Sel);
4140 Set_Entity (Sel, Any_Id);
4141 Set_Etype (Sel, Any_Type);
4143 end Analyze_Selected_Component;
4145 ---------------------------
4146 -- Analyze_Short_Circuit --
4147 ---------------------------
4149 procedure Analyze_Short_Circuit (N : Node_Id) is
4150 L : constant Node_Id := Left_Opnd (N);
4151 R : constant Node_Id := Right_Opnd (N);
4156 Analyze_Expression (L);
4157 Analyze_Expression (R);
4158 Set_Etype (N, Any_Type);
4160 if not Is_Overloaded (L) then
4161 if Root_Type (Etype (L)) = Standard_Boolean
4162 and then Has_Compatible_Type (R, Etype (L))
4164 Add_One_Interp (N, Etype (L), Etype (L));
4168 Get_First_Interp (L, Ind, It);
4169 while Present (It.Typ) loop
4170 if Root_Type (It.Typ) = Standard_Boolean
4171 and then Has_Compatible_Type (R, It.Typ)
4173 Add_One_Interp (N, It.Typ, It.Typ);
4176 Get_Next_Interp (Ind, It);
4180 -- Here we have failed to find an interpretation. Clearly we know that
4181 -- it is not the case that both operands can have an interpretation of
4182 -- Boolean, but this is by far the most likely intended interpretation.
4183 -- So we simply resolve both operands as Booleans, and at least one of
4184 -- these resolutions will generate an error message, and we do not need
4185 -- to give another error message on the short circuit operation itself.
4187 if Etype (N) = Any_Type then
4188 Resolve (L, Standard_Boolean);
4189 Resolve (R, Standard_Boolean);
4190 Set_Etype (N, Standard_Boolean);
4192 end Analyze_Short_Circuit;
4198 procedure Analyze_Slice (N : Node_Id) is
4199 P : constant Node_Id := Prefix (N);
4200 D : constant Node_Id := Discrete_Range (N);
4201 Array_Type : Entity_Id;
4203 procedure Analyze_Overloaded_Slice;
4204 -- If the prefix is overloaded, select those interpretations that
4205 -- yield a one-dimensional array type.
4207 ------------------------------
4208 -- Analyze_Overloaded_Slice --
4209 ------------------------------
4211 procedure Analyze_Overloaded_Slice is
4217 Set_Etype (N, Any_Type);
4219 Get_First_Interp (P, I, It);
4220 while Present (It.Nam) loop
4223 if Is_Access_Type (Typ) then
4224 Typ := Designated_Type (Typ);
4225 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4228 if Is_Array_Type (Typ)
4229 and then Number_Dimensions (Typ) = 1
4230 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
4232 Add_One_Interp (N, Typ, Typ);
4235 Get_Next_Interp (I, It);
4238 if Etype (N) = Any_Type then
4239 Error_Msg_N ("expect array type in prefix of slice", N);
4241 end Analyze_Overloaded_Slice;
4243 -- Start of processing for Analyze_Slice
4249 if Is_Overloaded (P) then
4250 Analyze_Overloaded_Slice;
4253 Array_Type := Etype (P);
4254 Set_Etype (N, Any_Type);
4256 if Is_Access_Type (Array_Type) then
4257 Array_Type := Designated_Type (Array_Type);
4258 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4261 if not Is_Array_Type (Array_Type) then
4262 Wrong_Type (P, Any_Array);
4264 elsif Number_Dimensions (Array_Type) > 1 then
4266 ("type is not one-dimensional array in slice prefix", N);
4269 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
4271 Wrong_Type (D, Etype (First_Index (Array_Type)));
4274 Set_Etype (N, Array_Type);
4279 -----------------------------
4280 -- Analyze_Type_Conversion --
4281 -----------------------------
4283 procedure Analyze_Type_Conversion (N : Node_Id) is
4284 Expr : constant Node_Id := Expression (N);
4288 -- If Conversion_OK is set, then the Etype is already set, and the
4289 -- only processing required is to analyze the expression. This is
4290 -- used to construct certain "illegal" conversions which are not
4291 -- allowed by Ada semantics, but can be handled OK by Gigi, see
4292 -- Sinfo for further details.
4294 if Conversion_OK (N) then
4299 -- Otherwise full type analysis is required, as well as some semantic
4300 -- checks to make sure the argument of the conversion is appropriate.
4302 Find_Type (Subtype_Mark (N));
4303 T := Entity (Subtype_Mark (N));
4305 Check_Fully_Declared (T, N);
4306 Analyze_Expression (Expr);
4307 Validate_Remote_Type_Type_Conversion (N);
4309 -- Only remaining step is validity checks on the argument. These
4310 -- are skipped if the conversion does not come from the source.
4312 if not Comes_From_Source (N) then
4315 -- If there was an error in a generic unit, no need to replicate the
4316 -- error message. Conversely, constant-folding in the generic may
4317 -- transform the argument of a conversion into a string literal, which
4318 -- is legal. Therefore the following tests are not performed in an
4321 elsif In_Instance then
4324 elsif Nkind (Expr) = N_Null then
4325 Error_Msg_N ("argument of conversion cannot be null", N);
4326 Error_Msg_N ("\use qualified expression instead", N);
4327 Set_Etype (N, Any_Type);
4329 elsif Nkind (Expr) = N_Aggregate then
4330 Error_Msg_N ("argument of conversion cannot be aggregate", N);
4331 Error_Msg_N ("\use qualified expression instead", N);
4333 elsif Nkind (Expr) = N_Allocator then
4334 Error_Msg_N ("argument of conversion cannot be an allocator", N);
4335 Error_Msg_N ("\use qualified expression instead", N);
4337 elsif Nkind (Expr) = N_String_Literal then
4338 Error_Msg_N ("argument of conversion cannot be string literal", N);
4339 Error_Msg_N ("\use qualified expression instead", N);
4341 elsif Nkind (Expr) = N_Character_Literal then
4342 if Ada_Version = Ada_83 then
4345 Error_Msg_N ("argument of conversion cannot be character literal",
4347 Error_Msg_N ("\use qualified expression instead", N);
4350 elsif Nkind (Expr) = N_Attribute_Reference
4352 (Attribute_Name (Expr) = Name_Access or else
4353 Attribute_Name (Expr) = Name_Unchecked_Access or else
4354 Attribute_Name (Expr) = Name_Unrestricted_Access)
4356 Error_Msg_N ("argument of conversion cannot be access", N);
4357 Error_Msg_N ("\use qualified expression instead", N);
4359 end Analyze_Type_Conversion;
4361 ----------------------
4362 -- Analyze_Unary_Op --
4363 ----------------------
4365 procedure Analyze_Unary_Op (N : Node_Id) is
4366 R : constant Node_Id := Right_Opnd (N);
4367 Op_Id : Entity_Id := Entity (N);
4370 Set_Etype (N, Any_Type);
4371 Candidate_Type := Empty;
4373 Analyze_Expression (R);
4375 if Present (Op_Id) then
4376 if Ekind (Op_Id) = E_Operator then
4377 Find_Unary_Types (R, Op_Id, N);
4379 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4383 Op_Id := Get_Name_Entity_Id (Chars (N));
4384 while Present (Op_Id) loop
4385 if Ekind (Op_Id) = E_Operator then
4386 if No (Next_Entity (First_Entity (Op_Id))) then
4387 Find_Unary_Types (R, Op_Id, N);
4390 elsif Is_Overloadable (Op_Id) then
4391 Analyze_User_Defined_Unary_Op (N, Op_Id);
4394 Op_Id := Homonym (Op_Id);
4399 end Analyze_Unary_Op;
4401 ----------------------------------
4402 -- Analyze_Unchecked_Expression --
4403 ----------------------------------
4405 procedure Analyze_Unchecked_Expression (N : Node_Id) is
4407 Analyze (Expression (N), Suppress => All_Checks);
4408 Set_Etype (N, Etype (Expression (N)));
4409 Save_Interps (Expression (N), N);
4410 end Analyze_Unchecked_Expression;
4412 ---------------------------------------
4413 -- Analyze_Unchecked_Type_Conversion --
4414 ---------------------------------------
4416 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
4418 Find_Type (Subtype_Mark (N));
4419 Analyze_Expression (Expression (N));
4420 Set_Etype (N, Entity (Subtype_Mark (N)));
4421 end Analyze_Unchecked_Type_Conversion;
4423 ------------------------------------
4424 -- Analyze_User_Defined_Binary_Op --
4425 ------------------------------------
4427 procedure Analyze_User_Defined_Binary_Op
4432 -- Only do analysis if the operator Comes_From_Source, since otherwise
4433 -- the operator was generated by the expander, and all such operators
4434 -- always refer to the operators in package Standard.
4436 if Comes_From_Source (N) then
4438 F1 : constant Entity_Id := First_Formal (Op_Id);
4439 F2 : constant Entity_Id := Next_Formal (F1);
4442 -- Verify that Op_Id is a visible binary function. Note that since
4443 -- we know Op_Id is overloaded, potentially use visible means use
4444 -- visible for sure (RM 9.4(11)).
4446 if Ekind (Op_Id) = E_Function
4447 and then Present (F2)
4448 and then (Is_Immediately_Visible (Op_Id)
4449 or else Is_Potentially_Use_Visible (Op_Id))
4450 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
4451 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
4453 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4455 -- If the left operand is overloaded, indicate that the
4456 -- current type is a viable candidate. This is redundant
4457 -- in most cases, but for equality and comparison operators
4458 -- where the context does not impose a type on the operands,
4459 -- setting the proper type is necessary to avoid subsequent
4460 -- ambiguities during resolution, when both user-defined and
4461 -- predefined operators may be candidates.
4463 if Is_Overloaded (Left_Opnd (N)) then
4464 Set_Etype (Left_Opnd (N), Etype (F1));
4467 if Debug_Flag_E then
4468 Write_Str ("user defined operator ");
4469 Write_Name (Chars (Op_Id));
4470 Write_Str (" on node ");
4471 Write_Int (Int (N));
4477 end Analyze_User_Defined_Binary_Op;
4479 -----------------------------------
4480 -- Analyze_User_Defined_Unary_Op --
4481 -----------------------------------
4483 procedure Analyze_User_Defined_Unary_Op
4488 -- Only do analysis if the operator Comes_From_Source, since otherwise
4489 -- the operator was generated by the expander, and all such operators
4490 -- always refer to the operators in package Standard.
4492 if Comes_From_Source (N) then
4494 F : constant Entity_Id := First_Formal (Op_Id);
4497 -- Verify that Op_Id is a visible unary function. Note that since
4498 -- we know Op_Id is overloaded, potentially use visible means use
4499 -- visible for sure (RM 9.4(11)).
4501 if Ekind (Op_Id) = E_Function
4502 and then No (Next_Formal (F))
4503 and then (Is_Immediately_Visible (Op_Id)
4504 or else Is_Potentially_Use_Visible (Op_Id))
4505 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
4507 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4511 end Analyze_User_Defined_Unary_Op;
4513 ---------------------------
4514 -- Check_Arithmetic_Pair --
4515 ---------------------------
4517 procedure Check_Arithmetic_Pair
4518 (T1, T2 : Entity_Id;
4522 Op_Name : constant Name_Id := Chars (Op_Id);
4524 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
4525 -- Check whether the fixed-point type Typ has a user-defined operator
4526 -- (multiplication or division) that should hide the corresponding
4527 -- predefined operator. Used to implement Ada 2005 AI-264, to make
4528 -- such operators more visible and therefore useful.
4530 -- If the name of the operation is an expanded name with prefix
4531 -- Standard, the predefined universal fixed operator is available,
4532 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
4534 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
4535 -- Get specific type (i.e. non-universal type if there is one)
4541 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
4542 Bas : constant Entity_Id := Base_Type (Typ);
4548 -- If the universal_fixed operation is given explicitly the rule
4549 -- concerning primitive operations of the type do not apply.
4551 if Nkind (N) = N_Function_Call
4552 and then Nkind (Name (N)) = N_Expanded_Name
4553 and then Entity (Prefix (Name (N))) = Standard_Standard
4558 -- The operation is treated as primitive if it is declared in the
4559 -- same scope as the type, and therefore on the same entity chain.
4561 Ent := Next_Entity (Typ);
4562 while Present (Ent) loop
4563 if Chars (Ent) = Chars (Op) then
4564 F1 := First_Formal (Ent);
4565 F2 := Next_Formal (F1);
4567 -- The operation counts as primitive if either operand or
4568 -- result are of the given base type, and both operands are
4569 -- fixed point types.
4571 if (Base_Type (Etype (F1)) = Bas
4572 and then Is_Fixed_Point_Type (Etype (F2)))
4575 (Base_Type (Etype (F2)) = Bas
4576 and then Is_Fixed_Point_Type (Etype (F1)))
4579 (Base_Type (Etype (Ent)) = Bas
4580 and then Is_Fixed_Point_Type (Etype (F1))
4581 and then Is_Fixed_Point_Type (Etype (F2)))
4597 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4599 if T1 = Universal_Integer or else T1 = Universal_Real then
4600 return Base_Type (T2);
4602 return Base_Type (T1);
4606 -- Start of processing for Check_Arithmetic_Pair
4609 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4611 if Is_Numeric_Type (T1)
4612 and then Is_Numeric_Type (T2)
4613 and then (Covers (T1 => T1, T2 => T2)
4615 Covers (T1 => T2, T2 => T1))
4617 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4620 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4622 if Is_Fixed_Point_Type (T1)
4623 and then (Is_Fixed_Point_Type (T2)
4624 or else T2 = Universal_Real)
4626 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4627 -- and no further processing is required (this is the case of an
4628 -- operator constructed by Exp_Fixd for a fixed point operation)
4629 -- Otherwise add one interpretation with universal fixed result
4630 -- If the operator is given in functional notation, it comes
4631 -- from source and Fixed_As_Integer cannot apply.
4633 if (Nkind (N) not in N_Op
4634 or else not Treat_Fixed_As_Integer (N))
4636 (not Has_Fixed_Op (T1, Op_Id)
4637 or else Nkind (Parent (N)) = N_Type_Conversion)
4639 Add_One_Interp (N, Op_Id, Universal_Fixed);
4642 elsif Is_Fixed_Point_Type (T2)
4643 and then (Nkind (N) not in N_Op
4644 or else not Treat_Fixed_As_Integer (N))
4645 and then T1 = Universal_Real
4647 (not Has_Fixed_Op (T1, Op_Id)
4648 or else Nkind (Parent (N)) = N_Type_Conversion)
4650 Add_One_Interp (N, Op_Id, Universal_Fixed);
4652 elsif Is_Numeric_Type (T1)
4653 and then Is_Numeric_Type (T2)
4654 and then (Covers (T1 => T1, T2 => T2)
4656 Covers (T1 => T2, T2 => T1))
4658 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4660 elsif Is_Fixed_Point_Type (T1)
4661 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4662 or else T2 = Universal_Integer)
4664 Add_One_Interp (N, Op_Id, T1);
4666 elsif T2 = Universal_Real
4667 and then Base_Type (T1) = Base_Type (Standard_Integer)
4668 and then Op_Name = Name_Op_Multiply
4670 Add_One_Interp (N, Op_Id, Any_Fixed);
4672 elsif T1 = Universal_Real
4673 and then Base_Type (T2) = Base_Type (Standard_Integer)
4675 Add_One_Interp (N, Op_Id, Any_Fixed);
4677 elsif Is_Fixed_Point_Type (T2)
4678 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4679 or else T1 = Universal_Integer)
4680 and then Op_Name = Name_Op_Multiply
4682 Add_One_Interp (N, Op_Id, T2);
4684 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4685 Add_One_Interp (N, Op_Id, T1);
4687 elsif T2 = Universal_Real
4688 and then T1 = Universal_Integer
4689 and then Op_Name = Name_Op_Multiply
4691 Add_One_Interp (N, Op_Id, T2);
4694 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4696 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4697 -- set does not require any special processing, since the Etype is
4698 -- already set (case of operation constructed by Exp_Fixed).
4700 if Is_Integer_Type (T1)
4701 and then (Covers (T1 => T1, T2 => T2)
4703 Covers (T1 => T2, T2 => T1))
4705 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4708 elsif Op_Name = Name_Op_Expon then
4709 if Is_Numeric_Type (T1)
4710 and then not Is_Fixed_Point_Type (T1)
4711 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4712 or else T2 = Universal_Integer)
4714 Add_One_Interp (N, Op_Id, Base_Type (T1));
4717 else pragma Assert (Nkind (N) in N_Op_Shift);
4719 -- If not one of the predefined operators, the node may be one
4720 -- of the intrinsic functions. Its kind is always specific, and
4721 -- we can use it directly, rather than the name of the operation.
4723 if Is_Integer_Type (T1)
4724 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4725 or else T2 = Universal_Integer)
4727 Add_One_Interp (N, Op_Id, Base_Type (T1));
4730 end Check_Arithmetic_Pair;
4732 -------------------------------
4733 -- Check_Misspelled_Selector --
4734 -------------------------------
4736 procedure Check_Misspelled_Selector
4737 (Prefix : Entity_Id;
4740 Max_Suggestions : constant := 2;
4741 Nr_Of_Suggestions : Natural := 0;
4743 Suggestion_1 : Entity_Id := Empty;
4744 Suggestion_2 : Entity_Id := Empty;
4749 -- All the components of the prefix of selector Sel are matched
4750 -- against Sel and a count is maintained of possible misspellings.
4751 -- When at the end of the analysis there are one or two (not more!)
4752 -- possible misspellings, these misspellings will be suggested as
4753 -- possible correction.
4755 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4757 -- Concurrent types should be handled as well ???
4762 Comp := First_Entity (Prefix);
4763 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4764 if Is_Visible_Component (Comp) then
4765 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4766 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4768 case Nr_Of_Suggestions is
4769 when 1 => Suggestion_1 := Comp;
4770 when 2 => Suggestion_2 := Comp;
4771 when others => exit;
4776 Comp := Next_Entity (Comp);
4779 -- Report at most two suggestions
4781 if Nr_Of_Suggestions = 1 then
4782 Error_Msg_NE -- CODEFIX
4783 ("\possible misspelling of&", Sel, Suggestion_1);
4785 elsif Nr_Of_Suggestions = 2 then
4786 Error_Msg_Node_2 := Suggestion_2;
4787 Error_Msg_NE -- CODEFIX
4788 ("\possible misspelling of& or&", Sel, Suggestion_1);
4790 end Check_Misspelled_Selector;
4792 ----------------------
4793 -- Defined_In_Scope --
4794 ----------------------
4796 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4798 S1 : constant Entity_Id := Scope (Base_Type (T));
4801 or else (S1 = System_Aux_Id and then S = Scope (S1));
4802 end Defined_In_Scope;
4808 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4814 Void_Interp_Seen : Boolean := False;
4817 pragma Warnings (Off, Boolean);
4820 if Ada_Version >= Ada_2005 then
4821 Actual := First_Actual (N);
4822 while Present (Actual) loop
4824 -- Ada 2005 (AI-50217): Post an error in case of premature
4825 -- usage of an entity from the limited view.
4827 if not Analyzed (Etype (Actual))
4828 and then From_With_Type (Etype (Actual))
4830 Error_Msg_Qual_Level := 1;
4832 ("missing with_clause for scope of imported type&",
4833 Actual, Etype (Actual));
4834 Error_Msg_Qual_Level := 0;
4837 Next_Actual (Actual);
4841 -- Analyze each candidate call again, with full error reporting
4845 ("no candidate interpretations match the actuals:!", Nam);
4846 Err_Mode := All_Errors_Mode;
4847 All_Errors_Mode := True;
4849 -- If this is a call to an operation of a concurrent type,
4850 -- the failed interpretations have been removed from the
4851 -- name. Recover them to provide full diagnostics.
4853 if Nkind (Parent (Nam)) = N_Selected_Component then
4854 Set_Entity (Nam, Empty);
4855 New_Nam := New_Copy_Tree (Parent (Nam));
4856 Set_Is_Overloaded (New_Nam, False);
4857 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4858 Set_Parent (New_Nam, Parent (Parent (Nam)));
4859 Analyze_Selected_Component (New_Nam);
4860 Get_First_Interp (Selector_Name (New_Nam), X, It);
4862 Get_First_Interp (Nam, X, It);
4865 while Present (It.Nam) loop
4866 if Etype (It.Nam) = Standard_Void_Type then
4867 Void_Interp_Seen := True;
4870 Analyze_One_Call (N, It.Nam, True, Success);
4871 Get_Next_Interp (X, It);
4874 if Nkind (N) = N_Function_Call then
4875 Get_First_Interp (Nam, X, It);
4876 while Present (It.Nam) loop
4877 if Ekind_In (It.Nam, E_Function, E_Operator) then
4880 Get_Next_Interp (X, It);
4884 -- If all interpretations are procedures, this deserves a
4885 -- more precise message. Ditto if this appears as the prefix
4886 -- of a selected component, which may be a lexical error.
4889 ("\context requires function call, found procedure name", Nam);
4891 if Nkind (Parent (N)) = N_Selected_Component
4892 and then N = Prefix (Parent (N))
4894 Error_Msg_N -- CODEFIX
4895 ("\period should probably be semicolon", Parent (N));
4898 elsif Nkind (N) = N_Procedure_Call_Statement
4899 and then not Void_Interp_Seen
4902 "\function name found in procedure call", Nam);
4905 All_Errors_Mode := Err_Mode;
4908 ---------------------------
4909 -- Find_Arithmetic_Types --
4910 ---------------------------
4912 procedure Find_Arithmetic_Types
4917 Index1 : Interp_Index;
4918 Index2 : Interp_Index;
4922 procedure Check_Right_Argument (T : Entity_Id);
4923 -- Check right operand of operator
4925 --------------------------
4926 -- Check_Right_Argument --
4927 --------------------------
4929 procedure Check_Right_Argument (T : Entity_Id) is
4931 if not Is_Overloaded (R) then
4932 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4934 Get_First_Interp (R, Index2, It2);
4935 while Present (It2.Typ) loop
4936 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4937 Get_Next_Interp (Index2, It2);
4940 end Check_Right_Argument;
4942 -- Start of processing for Find_Arithmetic_Types
4945 if not Is_Overloaded (L) then
4946 Check_Right_Argument (Etype (L));
4949 Get_First_Interp (L, Index1, It1);
4950 while Present (It1.Typ) loop
4951 Check_Right_Argument (It1.Typ);
4952 Get_Next_Interp (Index1, It1);
4956 end Find_Arithmetic_Types;
4958 ------------------------
4959 -- Find_Boolean_Types --
4960 ------------------------
4962 procedure Find_Boolean_Types
4967 Index : Interp_Index;
4970 procedure Check_Numeric_Argument (T : Entity_Id);
4971 -- Special case for logical operations one of whose operands is an
4972 -- integer literal. If both are literal the result is any modular type.
4974 ----------------------------
4975 -- Check_Numeric_Argument --
4976 ----------------------------
4978 procedure Check_Numeric_Argument (T : Entity_Id) is
4980 if T = Universal_Integer then
4981 Add_One_Interp (N, Op_Id, Any_Modular);
4983 elsif Is_Modular_Integer_Type (T) then
4984 Add_One_Interp (N, Op_Id, T);
4986 end Check_Numeric_Argument;
4988 -- Start of processing for Find_Boolean_Types
4991 if not Is_Overloaded (L) then
4992 if Etype (L) = Universal_Integer
4993 or else Etype (L) = Any_Modular
4995 if not Is_Overloaded (R) then
4996 Check_Numeric_Argument (Etype (R));
4999 Get_First_Interp (R, Index, It);
5000 while Present (It.Typ) loop
5001 Check_Numeric_Argument (It.Typ);
5002 Get_Next_Interp (Index, It);
5006 -- If operands are aggregates, we must assume that they may be
5007 -- boolean arrays, and leave disambiguation for the second pass.
5008 -- If only one is an aggregate, verify that the other one has an
5009 -- interpretation as a boolean array
5011 elsif Nkind (L) = N_Aggregate then
5012 if Nkind (R) = N_Aggregate then
5013 Add_One_Interp (N, Op_Id, Etype (L));
5015 elsif not Is_Overloaded (R) then
5016 if Valid_Boolean_Arg (Etype (R)) then
5017 Add_One_Interp (N, Op_Id, Etype (R));
5021 Get_First_Interp (R, Index, It);
5022 while Present (It.Typ) loop
5023 if Valid_Boolean_Arg (It.Typ) then
5024 Add_One_Interp (N, Op_Id, It.Typ);
5027 Get_Next_Interp (Index, It);
5031 elsif Valid_Boolean_Arg (Etype (L))
5032 and then Has_Compatible_Type (R, Etype (L))
5034 Add_One_Interp (N, Op_Id, Etype (L));
5038 Get_First_Interp (L, Index, It);
5039 while Present (It.Typ) loop
5040 if Valid_Boolean_Arg (It.Typ)
5041 and then Has_Compatible_Type (R, It.Typ)
5043 Add_One_Interp (N, Op_Id, It.Typ);
5046 Get_Next_Interp (Index, It);
5049 end Find_Boolean_Types;
5051 ---------------------------
5052 -- Find_Comparison_Types --
5053 ---------------------------
5055 procedure Find_Comparison_Types
5060 Index : Interp_Index;
5062 Found : Boolean := False;
5065 Scop : Entity_Id := Empty;
5067 procedure Try_One_Interp (T1 : Entity_Id);
5068 -- Routine to try one proposed interpretation. Note that the context
5069 -- of the operator plays no role in resolving the arguments, so that
5070 -- if there is more than one interpretation of the operands that is
5071 -- compatible with comparison, the operation is ambiguous.
5073 --------------------
5074 -- Try_One_Interp --
5075 --------------------
5077 procedure Try_One_Interp (T1 : Entity_Id) is
5080 -- If the operator is an expanded name, then the type of the operand
5081 -- must be defined in the corresponding scope. If the type is
5082 -- universal, the context will impose the correct type.
5085 and then not Defined_In_Scope (T1, Scop)
5086 and then T1 /= Universal_Integer
5087 and then T1 /= Universal_Real
5088 and then T1 /= Any_String
5089 and then T1 /= Any_Composite
5094 if Valid_Comparison_Arg (T1)
5095 and then Has_Compatible_Type (R, T1)
5098 and then Base_Type (T1) /= Base_Type (T_F)
5100 It := Disambiguate (L, I_F, Index, Any_Type);
5102 if It = No_Interp then
5103 Ambiguous_Operands (N);
5104 Set_Etype (L, Any_Type);
5118 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5123 -- Start of processing for Find_Comparison_Types
5126 -- If left operand is aggregate, the right operand has to
5127 -- provide a usable type for it.
5129 if Nkind (L) = N_Aggregate
5130 and then Nkind (R) /= N_Aggregate
5132 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5136 if Nkind (N) = N_Function_Call
5137 and then Nkind (Name (N)) = N_Expanded_Name
5139 Scop := Entity (Prefix (Name (N)));
5141 -- The prefix may be a package renaming, and the subsequent test
5142 -- requires the original package.
5144 if Ekind (Scop) = E_Package
5145 and then Present (Renamed_Entity (Scop))
5147 Scop := Renamed_Entity (Scop);
5148 Set_Entity (Prefix (Name (N)), Scop);
5152 if not Is_Overloaded (L) then
5153 Try_One_Interp (Etype (L));
5156 Get_First_Interp (L, Index, It);
5157 while Present (It.Typ) loop
5158 Try_One_Interp (It.Typ);
5159 Get_Next_Interp (Index, It);
5162 end Find_Comparison_Types;
5164 ----------------------------------------
5165 -- Find_Non_Universal_Interpretations --
5166 ----------------------------------------
5168 procedure Find_Non_Universal_Interpretations
5174 Index : Interp_Index;
5178 if T1 = Universal_Integer
5179 or else T1 = Universal_Real
5181 if not Is_Overloaded (R) then
5183 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
5185 Get_First_Interp (R, Index, It);
5186 while Present (It.Typ) loop
5187 if Covers (It.Typ, T1) then
5189 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
5192 Get_Next_Interp (Index, It);
5196 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
5198 end Find_Non_Universal_Interpretations;
5200 ------------------------------
5201 -- Find_Concatenation_Types --
5202 ------------------------------
5204 procedure Find_Concatenation_Types
5209 Op_Type : constant Entity_Id := Etype (Op_Id);
5212 if Is_Array_Type (Op_Type)
5213 and then not Is_Limited_Type (Op_Type)
5215 and then (Has_Compatible_Type (L, Op_Type)
5217 Has_Compatible_Type (L, Component_Type (Op_Type)))
5219 and then (Has_Compatible_Type (R, Op_Type)
5221 Has_Compatible_Type (R, Component_Type (Op_Type)))
5223 Add_One_Interp (N, Op_Id, Op_Type);
5225 end Find_Concatenation_Types;
5227 -------------------------
5228 -- Find_Equality_Types --
5229 -------------------------
5231 procedure Find_Equality_Types
5236 Index : Interp_Index;
5238 Found : Boolean := False;
5241 Scop : Entity_Id := Empty;
5243 procedure Try_One_Interp (T1 : Entity_Id);
5244 -- The context of the equality operator plays no role in resolving the
5245 -- arguments, so that if there is more than one interpretation of the
5246 -- operands that is compatible with equality, the construct is ambiguous
5247 -- and an error can be emitted now, after trying to disambiguate, i.e.
5248 -- applying preference rules.
5250 --------------------
5251 -- Try_One_Interp --
5252 --------------------
5254 procedure Try_One_Interp (T1 : Entity_Id) is
5255 Bas : constant Entity_Id := Base_Type (T1);
5258 -- If the operator is an expanded name, then the type of the operand
5259 -- must be defined in the corresponding scope. If the type is
5260 -- universal, the context will impose the correct type. An anonymous
5261 -- type for a 'Access reference is also universal in this sense, as
5262 -- the actual type is obtained from context.
5263 -- In Ada 2005, the equality operator for anonymous access types
5264 -- is declared in Standard, and preference rules apply to it.
5266 if Present (Scop) then
5267 if Defined_In_Scope (T1, Scop)
5268 or else T1 = Universal_Integer
5269 or else T1 = Universal_Real
5270 or else T1 = Any_Access
5271 or else T1 = Any_String
5272 or else T1 = Any_Composite
5273 or else (Ekind (T1) = E_Access_Subprogram_Type
5274 and then not Comes_From_Source (T1))
5278 elsif Ekind (T1) = E_Anonymous_Access_Type
5279 and then Scop = Standard_Standard
5284 -- The scope does not contain an operator for the type
5289 -- If we have infix notation, the operator must be usable.
5290 -- Within an instance, if the type is already established we
5291 -- know it is correct.
5292 -- In Ada 2005, the equality on anonymous access types is declared
5293 -- in Standard, and is always visible.
5295 elsif In_Open_Scopes (Scope (Bas))
5296 or else Is_Potentially_Use_Visible (Bas)
5297 or else In_Use (Bas)
5298 or else (In_Use (Scope (Bas))
5299 and then not Is_Hidden (Bas))
5300 or else (In_Instance
5301 and then First_Subtype (T1) = First_Subtype (Etype (R)))
5302 or else Ekind (T1) = E_Anonymous_Access_Type
5307 -- Save candidate type for subsquent error message, if any
5309 if not Is_Limited_Type (T1) then
5310 Candidate_Type := T1;
5316 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
5317 -- Do not allow anonymous access types in equality operators.
5319 if Ada_Version < Ada_2005
5320 and then Ekind (T1) = E_Anonymous_Access_Type
5325 if T1 /= Standard_Void_Type
5326 and then not Is_Limited_Type (T1)
5327 and then not Is_Limited_Composite (T1)
5328 and then Has_Compatible_Type (R, T1)
5331 and then Base_Type (T1) /= Base_Type (T_F)
5333 It := Disambiguate (L, I_F, Index, Any_Type);
5335 if It = No_Interp then
5336 Ambiguous_Operands (N);
5337 Set_Etype (L, Any_Type);
5350 if not Analyzed (L) then
5354 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5356 -- Case of operator was not visible, Etype still set to Any_Type
5358 if Etype (N) = Any_Type then
5362 elsif Scop = Standard_Standard
5363 and then Ekind (T1) = E_Anonymous_Access_Type
5369 -- Start of processing for Find_Equality_Types
5372 -- If left operand is aggregate, the right operand has to
5373 -- provide a usable type for it.
5375 if Nkind (L) = N_Aggregate
5376 and then Nkind (R) /= N_Aggregate
5378 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5382 if Nkind (N) = N_Function_Call
5383 and then Nkind (Name (N)) = N_Expanded_Name
5385 Scop := Entity (Prefix (Name (N)));
5387 -- The prefix may be a package renaming, and the subsequent test
5388 -- requires the original package.
5390 if Ekind (Scop) = E_Package
5391 and then Present (Renamed_Entity (Scop))
5393 Scop := Renamed_Entity (Scop);
5394 Set_Entity (Prefix (Name (N)), Scop);
5398 if not Is_Overloaded (L) then
5399 Try_One_Interp (Etype (L));
5402 Get_First_Interp (L, Index, It);
5403 while Present (It.Typ) loop
5404 Try_One_Interp (It.Typ);
5405 Get_Next_Interp (Index, It);
5408 end Find_Equality_Types;
5410 -------------------------
5411 -- Find_Negation_Types --
5412 -------------------------
5414 procedure Find_Negation_Types
5419 Index : Interp_Index;
5423 if not Is_Overloaded (R) then
5424 if Etype (R) = Universal_Integer then
5425 Add_One_Interp (N, Op_Id, Any_Modular);
5426 elsif Valid_Boolean_Arg (Etype (R)) then
5427 Add_One_Interp (N, Op_Id, Etype (R));
5431 Get_First_Interp (R, Index, It);
5432 while Present (It.Typ) loop
5433 if Valid_Boolean_Arg (It.Typ) then
5434 Add_One_Interp (N, Op_Id, It.Typ);
5437 Get_Next_Interp (Index, It);
5440 end Find_Negation_Types;
5442 ------------------------------
5443 -- Find_Primitive_Operation --
5444 ------------------------------
5446 function Find_Primitive_Operation (N : Node_Id) return Boolean is
5447 Obj : constant Node_Id := Prefix (N);
5448 Op : constant Node_Id := Selector_Name (N);
5455 Set_Etype (Op, Any_Type);
5457 if Is_Access_Type (Etype (Obj)) then
5458 Typ := Designated_Type (Etype (Obj));
5463 if Is_Class_Wide_Type (Typ) then
5464 Typ := Root_Type (Typ);
5467 Prims := Primitive_Operations (Typ);
5469 Prim := First_Elmt (Prims);
5470 while Present (Prim) loop
5471 if Chars (Node (Prim)) = Chars (Op) then
5472 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
5473 Set_Etype (N, Etype (Node (Prim)));
5479 -- Now look for class-wide operations of the type or any of its
5480 -- ancestors by iterating over the homonyms of the selector.
5483 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
5487 Hom := Current_Entity (Op);
5488 while Present (Hom) loop
5489 if (Ekind (Hom) = E_Procedure
5491 Ekind (Hom) = E_Function)
5492 and then Scope (Hom) = Scope (Typ)
5493 and then Present (First_Formal (Hom))
5495 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
5497 (Is_Access_Type (Etype (First_Formal (Hom)))
5499 Ekind (Etype (First_Formal (Hom))) =
5500 E_Anonymous_Access_Type
5503 (Designated_Type (Etype (First_Formal (Hom)))) =
5506 Add_One_Interp (Op, Hom, Etype (Hom));
5507 Set_Etype (N, Etype (Hom));
5510 Hom := Homonym (Hom);
5514 return Etype (Op) /= Any_Type;
5515 end Find_Primitive_Operation;
5517 ----------------------
5518 -- Find_Unary_Types --
5519 ----------------------
5521 procedure Find_Unary_Types
5526 Index : Interp_Index;
5530 if not Is_Overloaded (R) then
5531 if Is_Numeric_Type (Etype (R)) then
5532 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
5536 Get_First_Interp (R, Index, It);
5537 while Present (It.Typ) loop
5538 if Is_Numeric_Type (It.Typ) then
5539 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
5542 Get_Next_Interp (Index, It);
5545 end Find_Unary_Types;
5551 function Junk_Operand (N : Node_Id) return Boolean is
5555 if Error_Posted (N) then
5559 -- Get entity to be tested
5561 if Is_Entity_Name (N)
5562 and then Present (Entity (N))
5566 -- An odd case, a procedure name gets converted to a very peculiar
5567 -- function call, and here is where we detect this happening.
5569 elsif Nkind (N) = N_Function_Call
5570 and then Is_Entity_Name (Name (N))
5571 and then Present (Entity (Name (N)))
5575 -- Another odd case, there are at least some cases of selected
5576 -- components where the selected component is not marked as having
5577 -- an entity, even though the selector does have an entity
5579 elsif Nkind (N) = N_Selected_Component
5580 and then Present (Entity (Selector_Name (N)))
5582 Enode := Selector_Name (N);
5588 -- If OK_To_Reference is set for the entity, then don't complain, it
5589 -- means we are doing a preanalysis in which such complaints are wrong.
5591 if OK_To_Reference (Entity (Enode)) then
5595 -- Now test the entity we got to see if it is a bad case
5597 case Ekind (Entity (Enode)) is
5601 ("package name cannot be used as operand", Enode);
5603 when Generic_Unit_Kind =>
5605 ("generic unit name cannot be used as operand", Enode);
5609 ("subtype name cannot be used as operand", Enode);
5613 ("entry name cannot be used as operand", Enode);
5617 ("procedure name cannot be used as operand", Enode);
5621 ("exception name cannot be used as operand", Enode);
5623 when E_Block | E_Label | E_Loop =>
5625 ("label name cannot be used as operand", Enode);
5635 --------------------
5636 -- Operator_Check --
5637 --------------------
5639 procedure Operator_Check (N : Node_Id) is
5641 Remove_Abstract_Operations (N);
5643 -- Test for case of no interpretation found for operator
5645 if Etype (N) = Any_Type then
5649 Op_Id : Entity_Id := Empty;
5652 R := Right_Opnd (N);
5654 if Nkind (N) in N_Binary_Op then
5660 -- If either operand has no type, then don't complain further,
5661 -- since this simply means that we have a propagated error.
5664 or else Etype (R) = Any_Type
5665 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5669 -- We explicitly check for the case of concatenation of component
5670 -- with component to avoid reporting spurious matching array types
5671 -- that might happen to be lurking in distant packages (such as
5672 -- run-time packages). This also prevents inconsistencies in the
5673 -- messages for certain ACVC B tests, which can vary depending on
5674 -- types declared in run-time interfaces. Another improvement when
5675 -- aggregates are present is to look for a well-typed operand.
5677 elsif Present (Candidate_Type)
5678 and then (Nkind (N) /= N_Op_Concat
5679 or else Is_Array_Type (Etype (L))
5680 or else Is_Array_Type (Etype (R)))
5682 if Nkind (N) = N_Op_Concat then
5683 if Etype (L) /= Any_Composite
5684 and then Is_Array_Type (Etype (L))
5686 Candidate_Type := Etype (L);
5688 elsif Etype (R) /= Any_Composite
5689 and then Is_Array_Type (Etype (R))
5691 Candidate_Type := Etype (R);
5695 Error_Msg_NE -- CODEFIX
5696 ("operator for} is not directly visible!",
5697 N, First_Subtype (Candidate_Type));
5698 Error_Msg_N -- CODEFIX
5699 ("use clause would make operation legal!", N);
5702 -- If either operand is a junk operand (e.g. package name), then
5703 -- post appropriate error messages, but do not complain further.
5705 -- Note that the use of OR in this test instead of OR ELSE is
5706 -- quite deliberate, we may as well check both operands in the
5707 -- binary operator case.
5709 elsif Junk_Operand (R)
5710 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5714 -- If we have a logical operator, one of whose operands is
5715 -- Boolean, then we know that the other operand cannot resolve to
5716 -- Boolean (since we got no interpretations), but in that case we
5717 -- pretty much know that the other operand should be Boolean, so
5718 -- resolve it that way (generating an error)
5720 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5721 if Etype (L) = Standard_Boolean then
5722 Resolve (R, Standard_Boolean);
5724 elsif Etype (R) = Standard_Boolean then
5725 Resolve (L, Standard_Boolean);
5729 -- For an arithmetic operator or comparison operator, if one
5730 -- of the operands is numeric, then we know the other operand
5731 -- is not the same numeric type. If it is a non-numeric type,
5732 -- then probably it is intended to match the other operand.
5734 elsif Nkind_In (N, N_Op_Add,
5740 Nkind_In (N, N_Op_Lt,
5746 if Is_Numeric_Type (Etype (L))
5747 and then not Is_Numeric_Type (Etype (R))
5749 Resolve (R, Etype (L));
5752 elsif Is_Numeric_Type (Etype (R))
5753 and then not Is_Numeric_Type (Etype (L))
5755 Resolve (L, Etype (R));
5759 -- Comparisons on A'Access are common enough to deserve a
5762 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5763 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5764 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5767 ("two access attributes cannot be compared directly", N);
5769 ("\use qualified expression for one of the operands",
5773 -- Another one for C programmers
5775 elsif Nkind (N) = N_Op_Concat
5776 and then Valid_Boolean_Arg (Etype (L))
5777 and then Valid_Boolean_Arg (Etype (R))
5779 Error_Msg_N ("invalid operands for concatenation", N);
5780 Error_Msg_N -- CODEFIX
5781 ("\maybe AND was meant", N);
5784 -- A special case for comparison of access parameter with null
5786 elsif Nkind (N) = N_Op_Eq
5787 and then Is_Entity_Name (L)
5788 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5789 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5791 and then Nkind (R) = N_Null
5793 Error_Msg_N ("access parameter is not allowed to be null", L);
5794 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5797 -- Another special case for exponentiation, where the right
5798 -- operand must be Natural, independently of the base.
5800 elsif Nkind (N) = N_Op_Expon
5801 and then Is_Numeric_Type (Etype (L))
5802 and then not Is_Overloaded (R)
5804 First_Subtype (Base_Type (Etype (R))) /= Standard_Integer
5805 and then Base_Type (Etype (R)) /= Universal_Integer
5808 ("exponent must be of type Natural, found}", R, Etype (R));
5812 -- If we fall through then just give general message. Note that in
5813 -- the following messages, if the operand is overloaded we choose
5814 -- an arbitrary type to complain about, but that is probably more
5815 -- useful than not giving a type at all.
5817 if Nkind (N) in N_Unary_Op then
5818 Error_Msg_Node_2 := Etype (R);
5819 Error_Msg_N ("operator& not defined for}", N);
5823 if Nkind (N) in N_Binary_Op then
5824 if not Is_Overloaded (L)
5825 and then not Is_Overloaded (R)
5826 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5828 Error_Msg_Node_2 := First_Subtype (Etype (R));
5829 Error_Msg_N ("there is no applicable operator& for}", N);
5832 -- Another attempt to find a fix: one of the candidate
5833 -- interpretations may not be use-visible. This has
5834 -- already been checked for predefined operators, so
5835 -- we examine only user-defined functions.
5837 Op_Id := Get_Name_Entity_Id (Chars (N));
5839 while Present (Op_Id) loop
5840 if Ekind (Op_Id) /= E_Operator
5841 and then Is_Overloadable (Op_Id)
5843 if not Is_Immediately_Visible (Op_Id)
5844 and then not In_Use (Scope (Op_Id))
5845 and then not Is_Abstract_Subprogram (Op_Id)
5846 and then not Is_Hidden (Op_Id)
5847 and then Ekind (Scope (Op_Id)) = E_Package
5850 (L, Etype (First_Formal (Op_Id)))
5852 (Next_Formal (First_Formal (Op_Id)))
5856 Etype (Next_Formal (First_Formal (Op_Id))))
5859 ("No legal interpretation for operator&", N);
5861 ("\use clause on& would make operation legal",
5867 Op_Id := Homonym (Op_Id);
5871 Error_Msg_N ("invalid operand types for operator&", N);
5873 if Nkind (N) /= N_Op_Concat then
5874 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5875 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5885 -----------------------------------------
5886 -- Process_Implicit_Dereference_Prefix --
5887 -----------------------------------------
5889 function Process_Implicit_Dereference_Prefix
5891 P : Entity_Id) return Entity_Id
5894 Typ : constant Entity_Id := Designated_Type (Etype (P));
5898 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5900 -- We create a dummy reference to E to ensure that the reference
5901 -- is not considered as part of an assignment (an implicit
5902 -- dereference can never assign to its prefix). The Comes_From_Source
5903 -- attribute needs to be propagated for accurate warnings.
5905 Ref := New_Reference_To (E, Sloc (P));
5906 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5907 Generate_Reference (E, Ref);
5910 -- An implicit dereference is a legal occurrence of an
5911 -- incomplete type imported through a limited_with clause,
5912 -- if the full view is visible.
5914 if From_With_Type (Typ)
5915 and then not From_With_Type (Scope (Typ))
5917 (Is_Immediately_Visible (Scope (Typ))
5919 (Is_Child_Unit (Scope (Typ))
5920 and then Is_Visible_Child_Unit (Scope (Typ))))
5922 return Available_View (Typ);
5927 end Process_Implicit_Dereference_Prefix;
5929 --------------------------------
5930 -- Remove_Abstract_Operations --
5931 --------------------------------
5933 procedure Remove_Abstract_Operations (N : Node_Id) is
5934 Abstract_Op : Entity_Id := Empty;
5935 Address_Kludge : Boolean := False;
5939 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5940 -- activate this if either extensions are enabled, or if the abstract
5941 -- operation in question comes from a predefined file. This latter test
5942 -- allows us to use abstract to make operations invisible to users. In
5943 -- particular, if type Address is non-private and abstract subprograms
5944 -- are used to hide its operators, they will be truly hidden.
5946 type Operand_Position is (First_Op, Second_Op);
5947 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5949 procedure Remove_Address_Interpretations (Op : Operand_Position);
5950 -- Ambiguities may arise when the operands are literal and the address
5951 -- operations in s-auxdec are visible. In that case, remove the
5952 -- interpretation of a literal as Address, to retain the semantics of
5953 -- Address as a private type.
5955 ------------------------------------
5956 -- Remove_Address_Interpretations --
5957 ------------------------------------
5959 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5963 if Is_Overloaded (N) then
5964 Get_First_Interp (N, I, It);
5965 while Present (It.Nam) loop
5966 Formal := First_Entity (It.Nam);
5968 if Op = Second_Op then
5969 Formal := Next_Entity (Formal);
5972 if Is_Descendent_Of_Address (Etype (Formal)) then
5973 Address_Kludge := True;
5977 Get_Next_Interp (I, It);
5980 end Remove_Address_Interpretations;
5982 -- Start of processing for Remove_Abstract_Operations
5985 if Is_Overloaded (N) then
5986 Get_First_Interp (N, I, It);
5988 while Present (It.Nam) loop
5989 if Is_Overloadable (It.Nam)
5990 and then Is_Abstract_Subprogram (It.Nam)
5991 and then not Is_Dispatching_Operation (It.Nam)
5993 Abstract_Op := It.Nam;
5995 if Is_Descendent_Of_Address (It.Typ) then
5996 Address_Kludge := True;
6000 -- In Ada 2005, this operation does not participate in Overload
6001 -- resolution. If the operation is defined in a predefined
6002 -- unit, it is one of the operations declared abstract in some
6003 -- variants of System, and it must be removed as well.
6005 elsif Ada_Version >= Ada_2005
6006 or else Is_Predefined_File_Name
6007 (Unit_File_Name (Get_Source_Unit (It.Nam)))
6014 Get_Next_Interp (I, It);
6017 if No (Abstract_Op) then
6019 -- If some interpretation yields an integer type, it is still
6020 -- possible that there are address interpretations. Remove them
6021 -- if one operand is a literal, to avoid spurious ambiguities
6022 -- on systems where Address is a visible integer type.
6024 if Is_Overloaded (N)
6025 and then Nkind (N) in N_Op
6026 and then Is_Integer_Type (Etype (N))
6028 if Nkind (N) in N_Binary_Op then
6029 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
6030 Remove_Address_Interpretations (Second_Op);
6032 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
6033 Remove_Address_Interpretations (First_Op);
6038 elsif Nkind (N) in N_Op then
6040 -- Remove interpretations that treat literals as addresses. This
6041 -- is never appropriate, even when Address is defined as a visible
6042 -- Integer type. The reason is that we would really prefer Address
6043 -- to behave as a private type, even in this case, which is there
6044 -- only to accommodate oddities of VMS address sizes. If Address
6045 -- is a visible integer type, we get lots of overload ambiguities.
6047 if Nkind (N) in N_Binary_Op then
6049 U1 : constant Boolean :=
6050 Present (Universal_Interpretation (Right_Opnd (N)));
6051 U2 : constant Boolean :=
6052 Present (Universal_Interpretation (Left_Opnd (N)));
6056 Remove_Address_Interpretations (Second_Op);
6060 Remove_Address_Interpretations (First_Op);
6063 if not (U1 and U2) then
6065 -- Remove corresponding predefined operator, which is
6066 -- always added to the overload set.
6068 Get_First_Interp (N, I, It);
6069 while Present (It.Nam) loop
6070 if Scope (It.Nam) = Standard_Standard
6071 and then Base_Type (It.Typ) =
6072 Base_Type (Etype (Abstract_Op))
6077 Get_Next_Interp (I, It);
6080 elsif Is_Overloaded (N)
6081 and then Present (Univ_Type)
6083 -- If both operands have a universal interpretation,
6084 -- it is still necessary to remove interpretations that
6085 -- yield Address. Any remaining ambiguities will be
6086 -- removed in Disambiguate.
6088 Get_First_Interp (N, I, It);
6089 while Present (It.Nam) loop
6090 if Is_Descendent_Of_Address (It.Typ) then
6093 elsif not Is_Type (It.Nam) then
6094 Set_Entity (N, It.Nam);
6097 Get_Next_Interp (I, It);
6103 elsif Nkind (N) = N_Function_Call
6105 (Nkind (Name (N)) = N_Operator_Symbol
6107 (Nkind (Name (N)) = N_Expanded_Name
6109 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
6113 Arg1 : constant Node_Id := First (Parameter_Associations (N));
6114 U1 : constant Boolean :=
6115 Present (Universal_Interpretation (Arg1));
6116 U2 : constant Boolean :=
6117 Present (Next (Arg1)) and then
6118 Present (Universal_Interpretation (Next (Arg1)));
6122 Remove_Address_Interpretations (First_Op);
6126 Remove_Address_Interpretations (Second_Op);
6129 if not (U1 and U2) then
6130 Get_First_Interp (N, I, It);
6131 while Present (It.Nam) loop
6132 if Scope (It.Nam) = Standard_Standard
6133 and then It.Typ = Base_Type (Etype (Abstract_Op))
6138 Get_Next_Interp (I, It);
6144 -- If the removal has left no valid interpretations, emit an error
6145 -- message now and label node as illegal.
6147 if Present (Abstract_Op) then
6148 Get_First_Interp (N, I, It);
6152 -- Removal of abstract operation left no viable candidate
6154 Set_Etype (N, Any_Type);
6155 Error_Msg_Sloc := Sloc (Abstract_Op);
6157 ("cannot call abstract operation& declared#", N, Abstract_Op);
6159 -- In Ada 2005, an abstract operation may disable predefined
6160 -- operators. Since the context is not yet known, we mark the
6161 -- predefined operators as potentially hidden. Do not include
6162 -- predefined operators when addresses are involved since this
6163 -- case is handled separately.
6165 elsif Ada_Version >= Ada_2005
6166 and then not Address_Kludge
6168 while Present (It.Nam) loop
6169 if Is_Numeric_Type (It.Typ)
6170 and then Scope (It.Typ) = Standard_Standard
6172 Set_Abstract_Op (I, Abstract_Op);
6175 Get_Next_Interp (I, It);
6180 end Remove_Abstract_Operations;
6182 -----------------------
6183 -- Try_Indirect_Call --
6184 -----------------------
6186 function Try_Indirect_Call
6189 Typ : Entity_Id) return Boolean
6195 pragma Warnings (Off, Call_OK);
6198 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
6200 Actual := First_Actual (N);
6201 Formal := First_Formal (Designated_Type (Typ));
6202 while Present (Actual) and then Present (Formal) loop
6203 if not Has_Compatible_Type (Actual, Etype (Formal)) then
6208 Next_Formal (Formal);
6211 if No (Actual) and then No (Formal) then
6212 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
6214 -- Nam is a candidate interpretation for the name in the call,
6215 -- if it is not an indirect call.
6217 if not Is_Type (Nam)
6218 and then Is_Entity_Name (Name (N))
6220 Set_Entity (Name (N), Nam);
6227 end Try_Indirect_Call;
6229 ----------------------
6230 -- Try_Indexed_Call --
6231 ----------------------
6233 function Try_Indexed_Call
6237 Skip_First : Boolean) return Boolean
6239 Loc : constant Source_Ptr := Sloc (N);
6240 Actuals : constant List_Id := Parameter_Associations (N);
6245 Actual := First (Actuals);
6247 -- If the call was originally written in prefix form, skip the first
6248 -- actual, which is obviously not defaulted.
6254 Index := First_Index (Typ);
6255 while Present (Actual) and then Present (Index) loop
6257 -- If the parameter list has a named association, the expression
6258 -- is definitely a call and not an indexed component.
6260 if Nkind (Actual) = N_Parameter_Association then
6264 if Is_Entity_Name (Actual)
6265 and then Is_Type (Entity (Actual))
6266 and then No (Next (Actual))
6268 -- A single actual that is a type name indicates a slice if the
6269 -- type is discrete, and an error otherwise.
6271 if Is_Discrete_Type (Entity (Actual)) then
6275 Make_Function_Call (Loc,
6276 Name => Relocate_Node (Name (N))),
6278 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
6283 Error_Msg_N ("invalid use of type in expression", Actual);
6284 Set_Etype (N, Any_Type);
6289 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
6297 if No (Actual) and then No (Index) then
6298 Add_One_Interp (N, Nam, Component_Type (Typ));
6300 -- Nam is a candidate interpretation for the name in the call,
6301 -- if it is not an indirect call.
6303 if not Is_Type (Nam)
6304 and then Is_Entity_Name (Name (N))
6306 Set_Entity (Name (N), Nam);
6313 end Try_Indexed_Call;
6315 --------------------------
6316 -- Try_Object_Operation --
6317 --------------------------
6319 function Try_Object_Operation (N : Node_Id) return Boolean is
6320 K : constant Node_Kind := Nkind (Parent (N));
6321 Is_Subprg_Call : constant Boolean := Nkind_In
6322 (K, N_Procedure_Call_Statement,
6324 Loc : constant Source_Ptr := Sloc (N);
6325 Obj : constant Node_Id := Prefix (N);
6327 Subprog : constant Node_Id :=
6328 Make_Identifier (Sloc (Selector_Name (N)),
6329 Chars => Chars (Selector_Name (N)));
6330 -- Identifier on which possible interpretations will be collected
6332 Report_Error : Boolean := False;
6333 -- If no candidate interpretation matches the context, redo the
6334 -- analysis with error enabled to provide additional information.
6337 Candidate : Entity_Id := Empty;
6338 New_Call_Node : Node_Id := Empty;
6339 Node_To_Replace : Node_Id;
6340 Obj_Type : Entity_Id := Etype (Obj);
6341 Success : Boolean := False;
6343 function Valid_Candidate
6346 Subp : Entity_Id) return Entity_Id;
6347 -- If the subprogram is a valid interpretation, record it, and add
6348 -- to the list of interpretations of Subprog.
6350 procedure Complete_Object_Operation
6351 (Call_Node : Node_Id;
6352 Node_To_Replace : Node_Id);
6353 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
6354 -- Call_Node, insert the object (or its dereference) as the first actual
6355 -- in the call, and complete the analysis of the call.
6357 procedure Report_Ambiguity (Op : Entity_Id);
6358 -- If a prefixed procedure call is ambiguous, indicate whether the
6359 -- call includes an implicit dereference or an implicit 'Access.
6361 procedure Transform_Object_Operation
6362 (Call_Node : out Node_Id;
6363 Node_To_Replace : out Node_Id);
6364 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
6365 -- Call_Node is the resulting subprogram call, Node_To_Replace is
6366 -- either N or the parent of N, and Subprog is a reference to the
6367 -- subprogram we are trying to match.
6369 function Try_Class_Wide_Operation
6370 (Call_Node : Node_Id;
6371 Node_To_Replace : Node_Id) return Boolean;
6372 -- Traverse all ancestor types looking for a class-wide subprogram
6373 -- for which the current operation is a valid non-dispatching call.
6375 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
6376 -- If prefix is overloaded, its interpretation may include different
6377 -- tagged types, and we must examine the primitive operations and
6378 -- the class-wide operations of each in order to find candidate
6379 -- interpretations for the call as a whole.
6381 function Try_Primitive_Operation
6382 (Call_Node : Node_Id;
6383 Node_To_Replace : Node_Id) return Boolean;
6384 -- Traverse the list of primitive subprograms looking for a dispatching
6385 -- operation for which the current node is a valid call .
6387 ---------------------
6388 -- Valid_Candidate --
6389 ---------------------
6391 function Valid_Candidate
6394 Subp : Entity_Id) return Entity_Id
6396 Arr_Type : Entity_Id;
6397 Comp_Type : Entity_Id;
6400 -- If the subprogram is a valid interpretation, record it in global
6401 -- variable Subprog, to collect all possible overloadings.
6404 if Subp /= Entity (Subprog) then
6405 Add_One_Interp (Subprog, Subp, Etype (Subp));
6409 -- If the call may be an indexed call, retrieve component type of
6410 -- resulting expression, and add possible interpretation.
6415 if Nkind (Call) = N_Function_Call
6416 and then Nkind (Parent (N)) = N_Indexed_Component
6417 and then Needs_One_Actual (Subp)
6419 if Is_Array_Type (Etype (Subp)) then
6420 Arr_Type := Etype (Subp);
6422 elsif Is_Access_Type (Etype (Subp))
6423 and then Is_Array_Type (Designated_Type (Etype (Subp)))
6425 Arr_Type := Designated_Type (Etype (Subp));
6429 if Present (Arr_Type) then
6431 -- Verify that the actuals (excluding the object) match the types
6439 Actual := Next (First_Actual (Call));
6440 Index := First_Index (Arr_Type);
6441 while Present (Actual) and then Present (Index) loop
6442 if not Has_Compatible_Type (Actual, Etype (Index)) then
6447 Next_Actual (Actual);
6453 and then Present (Arr_Type)
6455 Comp_Type := Component_Type (Arr_Type);
6459 if Present (Comp_Type)
6460 and then Etype (Subprog) /= Comp_Type
6462 Add_One_Interp (Subprog, Subp, Comp_Type);
6466 if Etype (Call) /= Any_Type then
6471 end Valid_Candidate;
6473 -------------------------------
6474 -- Complete_Object_Operation --
6475 -------------------------------
6477 procedure Complete_Object_Operation
6478 (Call_Node : Node_Id;
6479 Node_To_Replace : Node_Id)
6481 Control : constant Entity_Id := First_Formal (Entity (Subprog));
6482 Formal_Type : constant Entity_Id := Etype (Control);
6483 First_Actual : Node_Id;
6486 -- Place the name of the operation, with its interpretations,
6487 -- on the rewritten call.
6489 Set_Name (Call_Node, Subprog);
6491 First_Actual := First (Parameter_Associations (Call_Node));
6493 -- For cross-reference purposes, treat the new node as being in
6494 -- the source if the original one is.
6496 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
6497 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
6499 if Nkind (N) = N_Selected_Component
6500 and then not Inside_A_Generic
6502 Set_Entity (Selector_Name (N), Entity (Subprog));
6505 -- If need be, rewrite first actual as an explicit dereference
6506 -- If the call is overloaded, the rewriting can only be done
6507 -- once the primitive operation is identified.
6509 if Is_Overloaded (Subprog) then
6511 -- The prefix itself may be overloaded, and its interpretations
6512 -- must be propagated to the new actual in the call.
6514 if Is_Overloaded (Obj) then
6515 Save_Interps (Obj, First_Actual);
6518 Rewrite (First_Actual, Obj);
6520 elsif not Is_Access_Type (Formal_Type)
6521 and then Is_Access_Type (Etype (Obj))
6523 Rewrite (First_Actual,
6524 Make_Explicit_Dereference (Sloc (Obj), Obj));
6525 Analyze (First_Actual);
6527 -- If we need to introduce an explicit dereference, verify that
6528 -- the resulting actual is compatible with the mode of the formal.
6530 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
6531 and then Is_Access_Constant (Etype (Obj))
6534 ("expect variable in call to&", Prefix (N), Entity (Subprog));
6537 -- Conversely, if the formal is an access parameter and the object
6538 -- is not, replace the actual with a 'Access reference. Its analysis
6539 -- will check that the object is aliased.
6541 elsif Is_Access_Type (Formal_Type)
6542 and then not Is_Access_Type (Etype (Obj))
6544 -- A special case: A.all'access is illegal if A is an access to a
6545 -- constant and the context requires an access to a variable.
6547 if not Is_Access_Constant (Formal_Type) then
6548 if (Nkind (Obj) = N_Explicit_Dereference
6549 and then Is_Access_Constant (Etype (Prefix (Obj))))
6550 or else not Is_Variable (Obj)
6553 ("actual for& must be a variable", Obj, Control);
6557 Rewrite (First_Actual,
6558 Make_Attribute_Reference (Loc,
6559 Attribute_Name => Name_Access,
6560 Prefix => Relocate_Node (Obj)));
6562 if not Is_Aliased_View (Obj) then
6564 ("object in prefixed call to& must be aliased"
6565 & " (RM-2005 4.3.1 (13))",
6566 Prefix (First_Actual), Subprog);
6569 Analyze (First_Actual);
6572 if Is_Overloaded (Obj) then
6573 Save_Interps (Obj, First_Actual);
6576 Rewrite (First_Actual, Obj);
6579 Rewrite (Node_To_Replace, Call_Node);
6581 -- Propagate the interpretations collected in subprog to the new
6582 -- function call node, to be resolved from context.
6584 if Is_Overloaded (Subprog) then
6585 Save_Interps (Subprog, Node_To_Replace);
6588 Analyze (Node_To_Replace);
6590 -- If the operation has been rewritten into a call, which may get
6591 -- subsequently an explicit dereference, preserve the type on the
6592 -- original node (selected component or indexed component) for
6593 -- subsequent legality tests, e.g. Is_Variable. which examines
6594 -- the original node.
6596 if Nkind (Node_To_Replace) = N_Function_Call then
6598 (Original_Node (Node_To_Replace), Etype (Node_To_Replace));
6601 end Complete_Object_Operation;
6603 ----------------------
6604 -- Report_Ambiguity --
6605 ----------------------
6607 procedure Report_Ambiguity (Op : Entity_Id) is
6608 Access_Formal : constant Boolean :=
6609 Is_Access_Type (Etype (First_Formal (Op)));
6610 Access_Actual : constant Boolean :=
6611 Is_Access_Type (Etype (Prefix (N)));
6614 Error_Msg_Sloc := Sloc (Op);
6616 if Access_Formal and then not Access_Actual then
6617 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6619 ("\possible interpretation"
6620 & " (inherited, with implicit 'Access) #", N);
6623 ("\possible interpretation (with implicit 'Access) #", N);
6626 elsif not Access_Formal and then Access_Actual then
6627 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6629 ("\possible interpretation"
6630 & " ( inherited, with implicit dereference) #", N);
6633 ("\possible interpretation (with implicit dereference) #", N);
6637 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6638 Error_Msg_N ("\possible interpretation (inherited)#", N);
6640 Error_Msg_N -- CODEFIX
6641 ("\possible interpretation#", N);
6644 end Report_Ambiguity;
6646 --------------------------------
6647 -- Transform_Object_Operation --
6648 --------------------------------
6650 procedure Transform_Object_Operation
6651 (Call_Node : out Node_Id;
6652 Node_To_Replace : out Node_Id)
6654 Dummy : constant Node_Id := New_Copy (Obj);
6655 -- Placeholder used as a first parameter in the call, replaced
6656 -- eventually by the proper object.
6658 Parent_Node : constant Node_Id := Parent (N);
6664 -- Common case covering 1) Call to a procedure and 2) Call to a
6665 -- function that has some additional actuals.
6667 if Nkind_In (Parent_Node, N_Function_Call,
6668 N_Procedure_Call_Statement)
6670 -- N is a selected component node containing the name of the
6671 -- subprogram. If N is not the name of the parent node we must
6672 -- not replace the parent node by the new construct. This case
6673 -- occurs when N is a parameterless call to a subprogram that
6674 -- is an actual parameter of a call to another subprogram. For
6676 -- Some_Subprogram (..., Obj.Operation, ...)
6678 and then Name (Parent_Node) = N
6680 Node_To_Replace := Parent_Node;
6682 Actuals := Parameter_Associations (Parent_Node);
6684 if Present (Actuals) then
6685 Prepend (Dummy, Actuals);
6687 Actuals := New_List (Dummy);
6690 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6692 Make_Procedure_Call_Statement (Loc,
6693 Name => New_Copy (Subprog),
6694 Parameter_Associations => Actuals);
6698 Make_Function_Call (Loc,
6699 Name => New_Copy (Subprog),
6700 Parameter_Associations => Actuals);
6704 -- Before analysis, a function call appears as an indexed component
6705 -- if there are no named associations.
6707 elsif Nkind (Parent_Node) = N_Indexed_Component
6708 and then N = Prefix (Parent_Node)
6710 Node_To_Replace := Parent_Node;
6711 Actuals := Expressions (Parent_Node);
6713 Actual := First (Actuals);
6714 while Present (Actual) loop
6719 Prepend (Dummy, Actuals);
6722 Make_Function_Call (Loc,
6723 Name => New_Copy (Subprog),
6724 Parameter_Associations => Actuals);
6726 -- Parameterless call: Obj.F is rewritten as F (Obj)
6729 Node_To_Replace := N;
6732 Make_Function_Call (Loc,
6733 Name => New_Copy (Subprog),
6734 Parameter_Associations => New_List (Dummy));
6736 end Transform_Object_Operation;
6738 ------------------------------
6739 -- Try_Class_Wide_Operation --
6740 ------------------------------
6742 function Try_Class_Wide_Operation
6743 (Call_Node : Node_Id;
6744 Node_To_Replace : Node_Id) return Boolean
6746 Anc_Type : Entity_Id;
6747 Matching_Op : Entity_Id := Empty;
6750 procedure Traverse_Homonyms
6751 (Anc_Type : Entity_Id;
6752 Error : out Boolean);
6753 -- Traverse the homonym chain of the subprogram searching for those
6754 -- homonyms whose first formal has the Anc_Type's class-wide type,
6755 -- or an anonymous access type designating the class-wide type. If
6756 -- an ambiguity is detected, then Error is set to True.
6758 procedure Traverse_Interfaces
6759 (Anc_Type : Entity_Id;
6760 Error : out Boolean);
6761 -- Traverse the list of interfaces, if any, associated with Anc_Type
6762 -- and search for acceptable class-wide homonyms associated with each
6763 -- interface. If an ambiguity is detected, then Error is set to True.
6765 -----------------------
6766 -- Traverse_Homonyms --
6767 -----------------------
6769 procedure Traverse_Homonyms
6770 (Anc_Type : Entity_Id;
6771 Error : out Boolean)
6773 Cls_Type : Entity_Id;
6781 Cls_Type := Class_Wide_Type (Anc_Type);
6783 Hom := Current_Entity (Subprog);
6785 -- Find operation whose first parameter is of the class-wide
6786 -- type, a subtype thereof, or an anonymous access to same.
6788 while Present (Hom) loop
6789 if (Ekind (Hom) = E_Procedure
6791 Ekind (Hom) = E_Function)
6792 and then Scope (Hom) = Scope (Anc_Type)
6793 and then Present (First_Formal (Hom))
6795 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6797 (Is_Access_Type (Etype (First_Formal (Hom)))
6799 Ekind (Etype (First_Formal (Hom))) =
6800 E_Anonymous_Access_Type
6803 (Designated_Type (Etype (First_Formal (Hom)))) =
6806 Set_Etype (Call_Node, Any_Type);
6807 Set_Is_Overloaded (Call_Node, False);
6810 if No (Matching_Op) then
6811 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6812 Set_Etype (Call_Node, Any_Type);
6813 Set_Parent (Call_Node, Parent (Node_To_Replace));
6815 Set_Name (Call_Node, Hom_Ref);
6820 Report => Report_Error,
6822 Skip_First => True);
6825 Valid_Candidate (Success, Call_Node, Hom);
6831 Report => Report_Error,
6833 Skip_First => True);
6835 if Present (Valid_Candidate (Success, Call_Node, Hom))
6836 and then Nkind (Call_Node) /= N_Function_Call
6838 Error_Msg_NE ("ambiguous call to&", N, Hom);
6839 Report_Ambiguity (Matching_Op);
6840 Report_Ambiguity (Hom);
6847 Hom := Homonym (Hom);
6849 end Traverse_Homonyms;
6851 -------------------------
6852 -- Traverse_Interfaces --
6853 -------------------------
6855 procedure Traverse_Interfaces
6856 (Anc_Type : Entity_Id;
6857 Error : out Boolean)
6859 Intface_List : constant List_Id :=
6860 Abstract_Interface_List (Anc_Type);
6866 if Is_Non_Empty_List (Intface_List) then
6867 Intface := First (Intface_List);
6868 while Present (Intface) loop
6870 -- Look for acceptable class-wide homonyms associated with
6873 Traverse_Homonyms (Etype (Intface), Error);
6879 -- Continue the search by looking at each of the interface's
6880 -- associated interface ancestors.
6882 Traverse_Interfaces (Etype (Intface), Error);
6891 end Traverse_Interfaces;
6893 -- Start of processing for Try_Class_Wide_Operation
6896 -- Loop through ancestor types (including interfaces), traversing
6897 -- the homonym chain of the subprogram, trying out those homonyms
6898 -- whose first formal has the class-wide type of the ancestor, or
6899 -- an anonymous access type designating the class-wide type.
6901 Anc_Type := Obj_Type;
6903 -- Look for a match among homonyms associated with the ancestor
6905 Traverse_Homonyms (Anc_Type, Error);
6911 -- Continue the search for matches among homonyms associated with
6912 -- any interfaces implemented by the ancestor.
6914 Traverse_Interfaces (Anc_Type, Error);
6920 exit when Etype (Anc_Type) = Anc_Type;
6921 Anc_Type := Etype (Anc_Type);
6924 if Present (Matching_Op) then
6925 Set_Etype (Call_Node, Etype (Matching_Op));
6928 return Present (Matching_Op);
6929 end Try_Class_Wide_Operation;
6931 -----------------------------------
6932 -- Try_One_Prefix_Interpretation --
6933 -----------------------------------
6935 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6939 if Is_Access_Type (Obj_Type) then
6940 Obj_Type := Designated_Type (Obj_Type);
6943 if Ekind (Obj_Type) = E_Private_Subtype then
6944 Obj_Type := Base_Type (Obj_Type);
6947 if Is_Class_Wide_Type (Obj_Type) then
6948 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6951 -- The type may have be obtained through a limited_with clause,
6952 -- in which case the primitive operations are available on its
6953 -- non-limited view. If still incomplete, retrieve full view.
6955 if Ekind (Obj_Type) = E_Incomplete_Type
6956 and then From_With_Type (Obj_Type)
6958 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6961 -- If the object is not tagged, or the type is still an incomplete
6962 -- type, this is not a prefixed call.
6964 if not Is_Tagged_Type (Obj_Type)
6965 or else Is_Incomplete_Type (Obj_Type)
6970 if Try_Primitive_Operation
6971 (Call_Node => New_Call_Node,
6972 Node_To_Replace => Node_To_Replace)
6974 Try_Class_Wide_Operation
6975 (Call_Node => New_Call_Node,
6976 Node_To_Replace => Node_To_Replace)
6980 end Try_One_Prefix_Interpretation;
6982 -----------------------------
6983 -- Try_Primitive_Operation --
6984 -----------------------------
6986 function Try_Primitive_Operation
6987 (Call_Node : Node_Id;
6988 Node_To_Replace : Node_Id) return Boolean
6991 Prim_Op : Entity_Id;
6992 Matching_Op : Entity_Id := Empty;
6993 Prim_Op_Ref : Node_Id := Empty;
6995 Corr_Type : Entity_Id := Empty;
6996 -- If the prefix is a synchronized type, the controlling type of
6997 -- the primitive operation is the corresponding record type, else
6998 -- this is the object type itself.
7000 Success : Boolean := False;
7002 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
7003 -- For tagged types the candidate interpretations are found in
7004 -- the list of primitive operations of the type and its ancestors.
7005 -- For formal tagged types we have to find the operations declared
7006 -- in the same scope as the type (including in the generic formal
7007 -- part) because the type itself carries no primitive operations,
7008 -- except for formal derived types that inherit the operations of
7009 -- the parent and progenitors.
7010 -- If the context is a generic subprogram body, the generic formals
7011 -- are visible by name, but are not in the entity list of the
7012 -- subprogram because that list starts with the subprogram formals.
7013 -- We retrieve the candidate operations from the generic declaration.
7015 function Is_Private_Overriding (Op : Entity_Id) return Boolean;
7016 -- An operation that overrides an inherited operation in the private
7017 -- part of its package may be hidden, but if the inherited operation
7018 -- is visible a direct call to it will dispatch to the private one,
7019 -- which is therefore a valid candidate.
7021 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
7022 -- Verify that the prefix, dereferenced if need be, is a valid
7023 -- controlling argument in a call to Op. The remaining actuals
7024 -- are checked in the subsequent call to Analyze_One_Call.
7026 ------------------------------
7027 -- Collect_Generic_Type_Ops --
7028 ------------------------------
7030 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
7031 Bas : constant Entity_Id := Base_Type (T);
7032 Candidates : constant Elist_Id := New_Elmt_List;
7036 procedure Check_Candidate;
7037 -- The operation is a candidate if its first parameter is a
7038 -- controlling operand of the desired type.
7040 -----------------------
7041 -- Check_Candidate; --
7042 -----------------------
7044 procedure Check_Candidate is
7046 Formal := First_Formal (Subp);
7049 and then Is_Controlling_Formal (Formal)
7051 (Base_Type (Etype (Formal)) = Bas
7053 (Is_Access_Type (Etype (Formal))
7054 and then Designated_Type (Etype (Formal)) = Bas))
7056 Append_Elmt (Subp, Candidates);
7058 end Check_Candidate;
7060 -- Start of processing for Collect_Generic_Type_Ops
7063 if Is_Derived_Type (T) then
7064 return Primitive_Operations (T);
7066 elsif Ekind_In (Scope (T), E_Procedure, E_Function) then
7068 -- Scan the list of generic formals to find subprograms
7069 -- that may have a first controlling formal of the type.
7071 if Nkind (Unit_Declaration_Node (Scope (T)))
7072 = N_Generic_Subprogram_Declaration
7079 First (Generic_Formal_Declarations
7080 (Unit_Declaration_Node (Scope (T))));
7081 while Present (Decl) loop
7082 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
7083 Subp := Defining_Entity (Decl);
7094 -- Scan the list of entities declared in the same scope as
7095 -- the type. In general this will be an open scope, given that
7096 -- the call we are analyzing can only appear within a generic
7097 -- declaration or body (either the one that declares T, or a
7100 -- For a subtype representing a generic actual type, go to the
7103 if Is_Generic_Actual_Type (T) then
7104 Subp := First_Entity (Scope (Base_Type (T)));
7106 Subp := First_Entity (Scope (T));
7109 while Present (Subp) loop
7110 if Is_Overloadable (Subp) then
7119 end Collect_Generic_Type_Ops;
7121 ---------------------------
7122 -- Is_Private_Overriding --
7123 ---------------------------
7125 function Is_Private_Overriding (Op : Entity_Id) return Boolean is
7126 Visible_Op : constant Entity_Id := Homonym (Op);
7129 return Present (Visible_Op)
7130 and then Scope (Op) = Scope (Visible_Op)
7131 and then not Comes_From_Source (Visible_Op)
7132 and then Alias (Visible_Op) = Op
7133 and then not Is_Hidden (Visible_Op);
7134 end Is_Private_Overriding;
7136 -----------------------------
7137 -- Valid_First_Argument_Of --
7138 -----------------------------
7140 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
7141 Typ : Entity_Id := Etype (First_Formal (Op));
7144 if Is_Concurrent_Type (Typ)
7145 and then Present (Corresponding_Record_Type (Typ))
7147 Typ := Corresponding_Record_Type (Typ);
7150 -- Simple case. Object may be a subtype of the tagged type or
7151 -- may be the corresponding record of a synchronized type.
7153 return Obj_Type = Typ
7154 or else Base_Type (Obj_Type) = Typ
7155 or else Corr_Type = Typ
7157 -- Prefix can be dereferenced
7160 (Is_Access_Type (Corr_Type)
7161 and then Designated_Type (Corr_Type) = Typ)
7163 -- Formal is an access parameter, for which the object
7164 -- can provide an access.
7167 (Ekind (Typ) = E_Anonymous_Access_Type
7168 and then Designated_Type (Typ) = Base_Type (Corr_Type));
7169 end Valid_First_Argument_Of;
7171 -- Start of processing for Try_Primitive_Operation
7174 -- Look for subprograms in the list of primitive operations. The name
7175 -- must be identical, and the kind of call indicates the expected
7176 -- kind of operation (function or procedure). If the type is a
7177 -- (tagged) synchronized type, the primitive ops are attached to the
7178 -- corresponding record (base) type.
7180 if Is_Concurrent_Type (Obj_Type) then
7181 if Present (Corresponding_Record_Type (Obj_Type)) then
7182 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
7183 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
7185 Corr_Type := Obj_Type;
7186 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7189 elsif not Is_Generic_Type (Obj_Type) then
7190 Corr_Type := Obj_Type;
7191 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
7194 Corr_Type := Obj_Type;
7195 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7198 while Present (Elmt) loop
7199 Prim_Op := Node (Elmt);
7201 if Chars (Prim_Op) = Chars (Subprog)
7202 and then Present (First_Formal (Prim_Op))
7203 and then Valid_First_Argument_Of (Prim_Op)
7205 (Nkind (Call_Node) = N_Function_Call)
7206 = (Ekind (Prim_Op) = E_Function)
7208 -- Ada 2005 (AI-251): If this primitive operation corresponds
7209 -- with an immediate ancestor interface there is no need to add
7210 -- it to the list of interpretations; the corresponding aliased
7211 -- primitive is also in this list of primitive operations and
7212 -- will be used instead.
7214 if (Present (Interface_Alias (Prim_Op))
7215 and then Is_Ancestor (Find_Dispatching_Type
7216 (Alias (Prim_Op)), Corr_Type))
7218 -- Do not consider hidden primitives unless the type is in an
7219 -- open scope or we are within an instance, where visibility
7220 -- is known to be correct, or else if this is an overriding
7221 -- operation in the private part for an inherited operation.
7223 or else (Is_Hidden (Prim_Op)
7224 and then not Is_Immediately_Visible (Obj_Type)
7225 and then not In_Instance
7226 and then not Is_Private_Overriding (Prim_Op))
7231 Set_Etype (Call_Node, Any_Type);
7232 Set_Is_Overloaded (Call_Node, False);
7234 if No (Matching_Op) then
7235 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
7236 Candidate := Prim_Op;
7238 Set_Parent (Call_Node, Parent (Node_To_Replace));
7240 Set_Name (Call_Node, Prim_Op_Ref);
7246 Report => Report_Error,
7248 Skip_First => True);
7250 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
7252 -- More than one interpretation, collect for subsequent
7253 -- disambiguation. If this is a procedure call and there
7254 -- is another match, report ambiguity now.
7260 Report => Report_Error,
7262 Skip_First => True);
7264 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
7265 and then Nkind (Call_Node) /= N_Function_Call
7267 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
7268 Report_Ambiguity (Matching_Op);
7269 Report_Ambiguity (Prim_Op);
7279 if Present (Matching_Op) then
7280 Set_Etype (Call_Node, Etype (Matching_Op));
7283 return Present (Matching_Op);
7284 end Try_Primitive_Operation;
7286 -- Start of processing for Try_Object_Operation
7289 Analyze_Expression (Obj);
7291 -- Analyze the actuals if node is known to be a subprogram call
7293 if Is_Subprg_Call and then N = Name (Parent (N)) then
7294 Actual := First (Parameter_Associations (Parent (N)));
7295 while Present (Actual) loop
7296 Analyze_Expression (Actual);
7301 -- Build a subprogram call node, using a copy of Obj as its first
7302 -- actual. This is a placeholder, to be replaced by an explicit
7303 -- dereference when needed.
7305 Transform_Object_Operation
7306 (Call_Node => New_Call_Node,
7307 Node_To_Replace => Node_To_Replace);
7309 Set_Etype (New_Call_Node, Any_Type);
7310 Set_Etype (Subprog, Any_Type);
7311 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
7313 if not Is_Overloaded (Obj) then
7314 Try_One_Prefix_Interpretation (Obj_Type);
7321 Get_First_Interp (Obj, I, It);
7322 while Present (It.Nam) loop
7323 Try_One_Prefix_Interpretation (It.Typ);
7324 Get_Next_Interp (I, It);
7329 if Etype (New_Call_Node) /= Any_Type then
7330 Complete_Object_Operation
7331 (Call_Node => New_Call_Node,
7332 Node_To_Replace => Node_To_Replace);
7335 elsif Present (Candidate) then
7337 -- The argument list is not type correct. Re-analyze with error
7338 -- reporting enabled, and use one of the possible candidates.
7339 -- In All_Errors_Mode, re-analyze all failed interpretations.
7341 if All_Errors_Mode then
7342 Report_Error := True;
7343 if Try_Primitive_Operation
7344 (Call_Node => New_Call_Node,
7345 Node_To_Replace => Node_To_Replace)
7348 Try_Class_Wide_Operation
7349 (Call_Node => New_Call_Node,
7350 Node_To_Replace => Node_To_Replace)
7357 (N => New_Call_Node,
7361 Skip_First => True);
7364 -- No need for further errors
7369 -- There was no candidate operation, so report it as an error
7370 -- in the caller: Analyze_Selected_Component.
7374 end Try_Object_Operation;
7380 procedure wpo (T : Entity_Id) is
7385 if not Is_Tagged_Type (T) then
7389 E := First_Elmt (Primitive_Operations (Base_Type (T)));
7390 while Present (E) loop
7392 Write_Int (Int (Op));
7393 Write_Str (" === ");
7394 Write_Name (Chars (Op));
7396 Write_Name (Chars (Scope (Op)));