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 a degenerate
2444 -- membership test with a singleton value, i.e. a test for equality.
2448 if Is_Entity_Name (R)
2449 and then Is_Type (Entity (R))
2452 Check_Fully_Declared (Entity (R), R);
2454 elsif Ada_Version >= Ada_2012 then
2455 if Nkind (N) = N_In then
2471 -- In previous version of the language this is an error that will
2472 -- be diagnosed below.
2478 -- Compatibility between expression and subtype mark or range is
2479 -- checked during resolution. The result of the operation is Boolean
2482 Set_Etype (N, Standard_Boolean);
2484 if Comes_From_Source (N)
2485 and then Present (Right_Opnd (N))
2486 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2488 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2490 end Analyze_Membership_Op;
2492 ----------------------
2493 -- Analyze_Negation --
2494 ----------------------
2496 procedure Analyze_Negation (N : Node_Id) is
2497 R : constant Node_Id := Right_Opnd (N);
2498 Op_Id : Entity_Id := Entity (N);
2501 Set_Etype (N, Any_Type);
2502 Candidate_Type := Empty;
2504 Analyze_Expression (R);
2506 if Present (Op_Id) then
2507 if Ekind (Op_Id) = E_Operator then
2508 Find_Negation_Types (R, Op_Id, N);
2510 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2514 Op_Id := Get_Name_Entity_Id (Chars (N));
2515 while Present (Op_Id) loop
2516 if Ekind (Op_Id) = E_Operator then
2517 Find_Negation_Types (R, Op_Id, N);
2519 Analyze_User_Defined_Unary_Op (N, Op_Id);
2522 Op_Id := Homonym (Op_Id);
2527 end Analyze_Negation;
2533 procedure Analyze_Null (N : Node_Id) is
2535 Set_Etype (N, Any_Access);
2538 ----------------------
2539 -- Analyze_One_Call --
2540 ----------------------
2542 procedure Analyze_One_Call
2546 Success : out Boolean;
2547 Skip_First : Boolean := False)
2549 Actuals : constant List_Id := Parameter_Associations (N);
2550 Prev_T : constant Entity_Id := Etype (N);
2552 Must_Skip : constant Boolean := Skip_First
2553 or else Nkind (Original_Node (N)) = N_Selected_Component
2555 (Nkind (Original_Node (N)) = N_Indexed_Component
2556 and then Nkind (Prefix (Original_Node (N)))
2557 = N_Selected_Component);
2558 -- The first formal must be omitted from the match when trying to find
2559 -- a primitive operation that is a possible interpretation, and also
2560 -- after the call has been rewritten, because the corresponding actual
2561 -- is already known to be compatible, and because this may be an
2562 -- indexing of a call with default parameters.
2566 Is_Indexed : Boolean := False;
2567 Is_Indirect : Boolean := False;
2568 Subp_Type : constant Entity_Id := Etype (Nam);
2571 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2572 -- There may be a user-defined operator that hides the current
2573 -- interpretation. We must check for this independently of the
2574 -- analysis of the call with the user-defined operation, because
2575 -- the parameter names may be wrong and yet the hiding takes place.
2576 -- This fixes a problem with ACATS test B34014O.
2578 -- When the type Address is a visible integer type, and the DEC
2579 -- system extension is visible, the predefined operator may be
2580 -- hidden as well, by one of the address operations in auxdec.
2581 -- Finally, The abstract operations on address do not hide the
2582 -- predefined operator (this is the purpose of making them abstract).
2584 procedure Indicate_Name_And_Type;
2585 -- If candidate interpretation matches, indicate name and type of
2586 -- result on call node.
2588 ----------------------------
2589 -- Indicate_Name_And_Type --
2590 ----------------------------
2592 procedure Indicate_Name_And_Type is
2594 Add_One_Interp (N, Nam, Etype (Nam));
2597 -- If the prefix of the call is a name, indicate the entity
2598 -- being called. If it is not a name, it is an expression that
2599 -- denotes an access to subprogram or else an entry or family. In
2600 -- the latter case, the name is a selected component, and the entity
2601 -- being called is noted on the selector.
2603 if not Is_Type (Nam) then
2604 if Is_Entity_Name (Name (N)) then
2605 Set_Entity (Name (N), Nam);
2607 elsif Nkind (Name (N)) = N_Selected_Component then
2608 Set_Entity (Selector_Name (Name (N)), Nam);
2612 if Debug_Flag_E and not Report then
2613 Write_Str (" Overloaded call ");
2614 Write_Int (Int (N));
2615 Write_Str (" compatible with ");
2616 Write_Int (Int (Nam));
2619 end Indicate_Name_And_Type;
2621 ------------------------
2622 -- Operator_Hidden_By --
2623 ------------------------
2625 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2626 Act1 : constant Node_Id := First_Actual (N);
2627 Act2 : constant Node_Id := Next_Actual (Act1);
2628 Form1 : constant Entity_Id := First_Formal (Fun);
2629 Form2 : constant Entity_Id := Next_Formal (Form1);
2632 if Ekind (Fun) /= E_Function
2633 or else Is_Abstract_Subprogram (Fun)
2637 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2640 elsif Present (Form2) then
2642 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2647 elsif Present (Act2) then
2651 -- Now we know that the arity of the operator matches the function,
2652 -- and the function call is a valid interpretation. The function
2653 -- hides the operator if it has the right signature, or if one of
2654 -- its operands is a non-abstract operation on Address when this is
2655 -- a visible integer type.
2657 return Hides_Op (Fun, Nam)
2658 or else Is_Descendent_Of_Address (Etype (Form1))
2661 and then Is_Descendent_Of_Address (Etype (Form2)));
2662 end Operator_Hidden_By;
2664 -- Start of processing for Analyze_One_Call
2669 -- If the subprogram has no formals or if all the formals have defaults,
2670 -- and the return type is an array type, the node may denote an indexing
2671 -- of the result of a parameterless call. In Ada 2005, the subprogram
2672 -- may have one non-defaulted formal, and the call may have been written
2673 -- in prefix notation, so that the rebuilt parameter list has more than
2676 if not Is_Overloadable (Nam)
2677 and then Ekind (Nam) /= E_Subprogram_Type
2678 and then Ekind (Nam) /= E_Entry_Family
2683 -- An indexing requires at least one actual
2685 if not Is_Empty_List (Actuals)
2687 (Needs_No_Actuals (Nam)
2689 (Needs_One_Actual (Nam)
2690 and then Present (Next_Actual (First (Actuals)))))
2692 if Is_Array_Type (Subp_Type) then
2693 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2695 elsif Is_Access_Type (Subp_Type)
2696 and then Is_Array_Type (Designated_Type (Subp_Type))
2700 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2702 -- The prefix can also be a parameterless function that returns an
2703 -- access to subprogram, in which case this is an indirect call.
2704 -- If this succeeds, an explicit dereference is added later on,
2705 -- in Analyze_Call or Resolve_Call.
2707 elsif Is_Access_Type (Subp_Type)
2708 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2710 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2715 -- If the call has been transformed into a slice, it is of the form
2716 -- F (Subtype) where F is parameterless. The node has been rewritten in
2717 -- Try_Indexed_Call and there is nothing else to do.
2720 and then Nkind (N) = N_Slice
2726 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2730 -- If an indirect call is a possible interpretation, indicate
2731 -- success to the caller.
2737 -- Mismatch in number or names of parameters
2739 elsif Debug_Flag_E then
2740 Write_Str (" normalization fails in call ");
2741 Write_Int (Int (N));
2742 Write_Str (" with subprogram ");
2743 Write_Int (Int (Nam));
2747 -- If the context expects a function call, discard any interpretation
2748 -- that is a procedure. If the node is not overloaded, leave as is for
2749 -- better error reporting when type mismatch is found.
2751 elsif Nkind (N) = N_Function_Call
2752 and then Is_Overloaded (Name (N))
2753 and then Ekind (Nam) = E_Procedure
2757 -- Ditto for function calls in a procedure context
2759 elsif Nkind (N) = N_Procedure_Call_Statement
2760 and then Is_Overloaded (Name (N))
2761 and then Etype (Nam) /= Standard_Void_Type
2765 elsif No (Actuals) then
2767 -- If Normalize succeeds, then there are default parameters for
2770 Indicate_Name_And_Type;
2772 elsif Ekind (Nam) = E_Operator then
2773 if Nkind (N) = N_Procedure_Call_Statement then
2777 -- This can occur when the prefix of the call is an operator
2778 -- name or an expanded name whose selector is an operator name.
2780 Analyze_Operator_Call (N, Nam);
2782 if Etype (N) /= Prev_T then
2784 -- Check that operator is not hidden by a function interpretation
2786 if Is_Overloaded (Name (N)) then
2792 Get_First_Interp (Name (N), I, It);
2793 while Present (It.Nam) loop
2794 if Operator_Hidden_By (It.Nam) then
2795 Set_Etype (N, Prev_T);
2799 Get_Next_Interp (I, It);
2804 -- If operator matches formals, record its name on the call.
2805 -- If the operator is overloaded, Resolve will select the
2806 -- correct one from the list of interpretations. The call
2807 -- node itself carries the first candidate.
2809 Set_Entity (Name (N), Nam);
2812 elsif Report and then Etype (N) = Any_Type then
2813 Error_Msg_N ("incompatible arguments for operator", N);
2817 -- Normalize_Actuals has chained the named associations in the
2818 -- correct order of the formals.
2820 Actual := First_Actual (N);
2821 Formal := First_Formal (Nam);
2823 -- If we are analyzing a call rewritten from object notation,
2824 -- skip first actual, which may be rewritten later as an
2825 -- explicit dereference.
2828 Next_Actual (Actual);
2829 Next_Formal (Formal);
2832 while Present (Actual) and then Present (Formal) loop
2833 if Nkind (Parent (Actual)) /= N_Parameter_Association
2834 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2836 -- The actual can be compatible with the formal, but we must
2837 -- also check that the context is not an address type that is
2838 -- visibly an integer type, as is the case in VMS_64. In this
2839 -- case the use of literals is illegal, except in the body of
2840 -- descendents of system, where arithmetic operations on
2841 -- address are of course used.
2843 if Has_Compatible_Type (Actual, Etype (Formal))
2845 (Etype (Actual) /= Universal_Integer
2846 or else not Is_Descendent_Of_Address (Etype (Formal))
2848 Is_Predefined_File_Name
2849 (Unit_File_Name (Get_Source_Unit (N))))
2851 Next_Actual (Actual);
2852 Next_Formal (Formal);
2855 if Debug_Flag_E then
2856 Write_Str (" type checking fails in call ");
2857 Write_Int (Int (N));
2858 Write_Str (" with formal ");
2859 Write_Int (Int (Formal));
2860 Write_Str (" in subprogram ");
2861 Write_Int (Int (Nam));
2865 if Report and not Is_Indexed and not Is_Indirect then
2867 -- Ada 2005 (AI-251): Complete the error notification
2868 -- to help new Ada 2005 users.
2870 if Is_Class_Wide_Type (Etype (Formal))
2871 and then Is_Interface (Etype (Etype (Formal)))
2872 and then not Interface_Present_In_Ancestor
2873 (Typ => Etype (Actual),
2874 Iface => Etype (Etype (Formal)))
2877 ("(Ada 2005) does not implement interface }",
2878 Actual, Etype (Etype (Formal)));
2881 Wrong_Type (Actual, Etype (Formal));
2883 if Nkind (Actual) = N_Op_Eq
2884 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2886 Formal := First_Formal (Nam);
2887 while Present (Formal) loop
2888 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2889 Error_Msg_N -- CODEFIX
2890 ("possible misspelling of `='>`!", Actual);
2894 Next_Formal (Formal);
2898 if All_Errors_Mode then
2899 Error_Msg_Sloc := Sloc (Nam);
2901 if Etype (Formal) = Any_Type then
2903 ("there is no legal actual parameter", Actual);
2906 if Is_Overloadable (Nam)
2907 and then Present (Alias (Nam))
2908 and then not Comes_From_Source (Nam)
2911 ("\\ =='> in call to inherited operation & #!",
2914 elsif Ekind (Nam) = E_Subprogram_Type then
2916 Access_To_Subprogram_Typ :
2917 constant Entity_Id :=
2919 (Associated_Node_For_Itype (Nam));
2922 "\\ =='> in call to dereference of &#!",
2923 Actual, Access_To_Subprogram_Typ);
2928 ("\\ =='> in call to &#!", Actual, Nam);
2938 -- Normalize_Actuals has verified that a default value exists
2939 -- for this formal. Current actual names a subsequent formal.
2941 Next_Formal (Formal);
2945 -- On exit, all actuals match
2947 Indicate_Name_And_Type;
2949 end Analyze_One_Call;
2951 ---------------------------
2952 -- Analyze_Operator_Call --
2953 ---------------------------
2955 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2956 Op_Name : constant Name_Id := Chars (Op_Id);
2957 Act1 : constant Node_Id := First_Actual (N);
2958 Act2 : constant Node_Id := Next_Actual (Act1);
2961 -- Binary operator case
2963 if Present (Act2) then
2965 -- If more than two operands, then not binary operator after all
2967 if Present (Next_Actual (Act2)) then
2970 elsif Op_Name = Name_Op_Add
2971 or else Op_Name = Name_Op_Subtract
2972 or else Op_Name = Name_Op_Multiply
2973 or else Op_Name = Name_Op_Divide
2974 or else Op_Name = Name_Op_Mod
2975 or else Op_Name = Name_Op_Rem
2976 or else Op_Name = Name_Op_Expon
2978 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2980 elsif Op_Name = Name_Op_And
2981 or else Op_Name = Name_Op_Or
2982 or else Op_Name = Name_Op_Xor
2984 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2986 elsif Op_Name = Name_Op_Lt
2987 or else Op_Name = Name_Op_Le
2988 or else Op_Name = Name_Op_Gt
2989 or else Op_Name = Name_Op_Ge
2991 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2993 elsif Op_Name = Name_Op_Eq
2994 or else Op_Name = Name_Op_Ne
2996 Find_Equality_Types (Act1, Act2, Op_Id, N);
2998 elsif Op_Name = Name_Op_Concat then
2999 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
3001 -- Is this else null correct, or should it be an abort???
3007 -- Unary operator case
3010 if Op_Name = Name_Op_Subtract or else
3011 Op_Name = Name_Op_Add or else
3012 Op_Name = Name_Op_Abs
3014 Find_Unary_Types (Act1, Op_Id, N);
3017 Op_Name = Name_Op_Not
3019 Find_Negation_Types (Act1, Op_Id, N);
3021 -- Is this else null correct, or should it be an abort???
3027 end Analyze_Operator_Call;
3029 -------------------------------------------
3030 -- Analyze_Overloaded_Selected_Component --
3031 -------------------------------------------
3033 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
3034 Nam : constant Node_Id := Prefix (N);
3035 Sel : constant Node_Id := Selector_Name (N);
3042 Set_Etype (Sel, Any_Type);
3044 Get_First_Interp (Nam, I, It);
3045 while Present (It.Typ) loop
3046 if Is_Access_Type (It.Typ) then
3047 T := Designated_Type (It.Typ);
3048 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3053 if Is_Record_Type (T) then
3055 -- If the prefix is a class-wide type, the visible components are
3056 -- those of the base type.
3058 if Is_Class_Wide_Type (T) then
3062 Comp := First_Entity (T);
3063 while Present (Comp) loop
3064 if Chars (Comp) = Chars (Sel)
3065 and then Is_Visible_Component (Comp)
3068 -- AI05-105: if the context is an object renaming with
3069 -- an anonymous access type, the expected type of the
3070 -- object must be anonymous. This is a name resolution rule.
3072 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
3073 or else No (Access_Definition (Parent (N)))
3074 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
3076 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
3078 Set_Entity (Sel, Comp);
3079 Set_Etype (Sel, Etype (Comp));
3080 Add_One_Interp (N, Etype (Comp), Etype (Comp));
3082 -- This also specifies a candidate to resolve the name.
3083 -- Further overloading will be resolved from context.
3084 -- The selector name itself does not carry overloading
3087 Set_Etype (Nam, It.Typ);
3090 -- Named access type in the context of a renaming
3091 -- declaration with an access definition. Remove
3092 -- inapplicable candidate.
3101 elsif Is_Concurrent_Type (T) then
3102 Comp := First_Entity (T);
3103 while Present (Comp)
3104 and then Comp /= First_Private_Entity (T)
3106 if Chars (Comp) = Chars (Sel) then
3107 if Is_Overloadable (Comp) then
3108 Add_One_Interp (Sel, Comp, Etype (Comp));
3110 Set_Entity_With_Style_Check (Sel, Comp);
3111 Generate_Reference (Comp, Sel);
3114 Set_Etype (Sel, Etype (Comp));
3115 Set_Etype (N, Etype (Comp));
3116 Set_Etype (Nam, It.Typ);
3118 -- For access type case, introduce explicit dereference for
3119 -- more uniform treatment of entry calls. Do this only once
3120 -- if several interpretations yield an access type.
3122 if Is_Access_Type (Etype (Nam))
3123 and then Nkind (Nam) /= N_Explicit_Dereference
3125 Insert_Explicit_Dereference (Nam);
3127 (Warn_On_Dereference, "?implicit dereference", N);
3134 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3137 Get_Next_Interp (I, It);
3140 if Etype (N) = Any_Type
3141 and then not Try_Object_Operation (N)
3143 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
3144 Set_Entity (Sel, Any_Id);
3145 Set_Etype (Sel, Any_Type);
3147 end Analyze_Overloaded_Selected_Component;
3149 ----------------------------------
3150 -- Analyze_Qualified_Expression --
3151 ----------------------------------
3153 procedure Analyze_Qualified_Expression (N : Node_Id) is
3154 Mark : constant Entity_Id := Subtype_Mark (N);
3155 Expr : constant Node_Id := Expression (N);
3161 Analyze_Expression (Expr);
3163 Set_Etype (N, Any_Type);
3168 if T = Any_Type then
3172 Check_Fully_Declared (T, N);
3174 -- If expected type is class-wide, check for exact match before
3175 -- expansion, because if the expression is a dispatching call it
3176 -- may be rewritten as explicit dereference with class-wide result.
3177 -- If expression is overloaded, retain only interpretations that
3178 -- will yield exact matches.
3180 if Is_Class_Wide_Type (T) then
3181 if not Is_Overloaded (Expr) then
3182 if Base_Type (Etype (Expr)) /= Base_Type (T) then
3183 if Nkind (Expr) = N_Aggregate then
3184 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
3186 Wrong_Type (Expr, T);
3191 Get_First_Interp (Expr, I, It);
3193 while Present (It.Nam) loop
3194 if Base_Type (It.Typ) /= Base_Type (T) then
3198 Get_Next_Interp (I, It);
3204 end Analyze_Qualified_Expression;
3206 -----------------------------------
3207 -- Analyze_Quantified_Expression --
3208 -----------------------------------
3210 procedure Analyze_Quantified_Expression (N : Node_Id) is
3211 Loc : constant Source_Ptr := Sloc (N);
3212 Ent : constant Entity_Id :=
3214 (E_Loop, Current_Scope, Sloc (N), 'L');
3219 Set_Etype (Ent, Standard_Void_Type);
3220 Set_Parent (Ent, N);
3222 if Present (Loop_Parameter_Specification (N)) then
3224 Make_Iteration_Scheme (Loc,
3225 Loop_Parameter_Specification =>
3226 Loop_Parameter_Specification (N));
3229 Make_Iteration_Scheme (Loc,
3230 Iterator_Specification =>
3231 Iterator_Specification (N));
3235 Set_Parent (Iterator, N);
3236 Analyze_Iteration_Scheme (Iterator);
3238 -- The loop specification may have been converted into an
3239 -- iterator specification during its analysis. Update the
3240 -- quantified node accordingly.
3242 if Present (Iterator_Specification (Iterator)) then
3243 Set_Iterator_Specification
3244 (N, Iterator_Specification (Iterator));
3245 Set_Loop_Parameter_Specification (N, Empty);
3248 Analyze (Condition (N));
3251 Set_Etype (N, Standard_Boolean);
3252 end Analyze_Quantified_Expression;
3258 procedure Analyze_Range (N : Node_Id) is
3259 L : constant Node_Id := Low_Bound (N);
3260 H : constant Node_Id := High_Bound (N);
3261 I1, I2 : Interp_Index;
3264 procedure Check_Common_Type (T1, T2 : Entity_Id);
3265 -- Verify the compatibility of two types, and choose the
3266 -- non universal one if the other is universal.
3268 procedure Check_High_Bound (T : Entity_Id);
3269 -- Test one interpretation of the low bound against all those
3270 -- of the high bound.
3272 procedure Check_Universal_Expression (N : Node_Id);
3273 -- In Ada83, reject bounds of a universal range that are not
3274 -- literals or entity names.
3276 -----------------------
3277 -- Check_Common_Type --
3278 -----------------------
3280 procedure Check_Common_Type (T1, T2 : Entity_Id) is
3282 if Covers (T1 => T1, T2 => T2)
3284 Covers (T1 => T2, T2 => T1)
3286 if T1 = Universal_Integer
3287 or else T1 = Universal_Real
3288 or else T1 = Any_Character
3290 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
3293 Add_One_Interp (N, T1, T1);
3296 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
3299 end Check_Common_Type;
3301 ----------------------
3302 -- Check_High_Bound --
3303 ----------------------
3305 procedure Check_High_Bound (T : Entity_Id) is
3307 if not Is_Overloaded (H) then
3308 Check_Common_Type (T, Etype (H));
3310 Get_First_Interp (H, I2, It2);
3311 while Present (It2.Typ) loop
3312 Check_Common_Type (T, It2.Typ);
3313 Get_Next_Interp (I2, It2);
3316 end Check_High_Bound;
3318 -----------------------------
3319 -- Is_Universal_Expression --
3320 -----------------------------
3322 procedure Check_Universal_Expression (N : Node_Id) is
3324 if Etype (N) = Universal_Integer
3325 and then Nkind (N) /= N_Integer_Literal
3326 and then not Is_Entity_Name (N)
3327 and then Nkind (N) /= N_Attribute_Reference
3329 Error_Msg_N ("illegal bound in discrete range", N);
3331 end Check_Universal_Expression;
3333 -- Start of processing for Analyze_Range
3336 Set_Etype (N, Any_Type);
3337 Analyze_Expression (L);
3338 Analyze_Expression (H);
3340 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
3344 if not Is_Overloaded (L) then
3345 Check_High_Bound (Etype (L));
3347 Get_First_Interp (L, I1, It1);
3348 while Present (It1.Typ) loop
3349 Check_High_Bound (It1.Typ);
3350 Get_Next_Interp (I1, It1);
3354 -- If result is Any_Type, then we did not find a compatible pair
3356 if Etype (N) = Any_Type then
3357 Error_Msg_N ("incompatible types in range ", N);
3361 if Ada_Version = Ada_83
3363 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
3364 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
3366 Check_Universal_Expression (L);
3367 Check_Universal_Expression (H);
3371 -----------------------
3372 -- Analyze_Reference --
3373 -----------------------
3375 procedure Analyze_Reference (N : Node_Id) is
3376 P : constant Node_Id := Prefix (N);
3379 Acc_Type : Entity_Id;
3384 -- An interesting error check, if we take the 'Reference of an object
3385 -- for which a pragma Atomic or Volatile has been given, and the type
3386 -- of the object is not Atomic or Volatile, then we are in trouble. The
3387 -- problem is that no trace of the atomic/volatile status will remain
3388 -- for the backend to respect when it deals with the resulting pointer,
3389 -- since the pointer type will not be marked atomic (it is a pointer to
3390 -- the base type of the object).
3392 -- It is not clear if that can ever occur, but in case it does, we will
3393 -- generate an error message. Not clear if this message can ever be
3394 -- generated, and pretty clear that it represents a bug if it is, still
3395 -- seems worth checking, except in CodePeer mode where we do not really
3396 -- care and don't want to bother the user.
3400 if Is_Entity_Name (P)
3401 and then Is_Object_Reference (P)
3402 and then not CodePeer_Mode
3407 if (Has_Atomic_Components (E)
3408 and then not Has_Atomic_Components (T))
3410 (Has_Volatile_Components (E)
3411 and then not Has_Volatile_Components (T))
3412 or else (Is_Atomic (E) and then not Is_Atomic (T))
3413 or else (Is_Volatile (E) and then not Is_Volatile (T))
3415 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
3419 -- Carry on with normal processing
3421 Acc_Type := Create_Itype (E_Allocator_Type, N);
3422 Set_Etype (Acc_Type, Acc_Type);
3423 Set_Directly_Designated_Type (Acc_Type, Etype (P));
3424 Set_Etype (N, Acc_Type);
3425 end Analyze_Reference;
3427 --------------------------------
3428 -- Analyze_Selected_Component --
3429 --------------------------------
3431 -- Prefix is a record type or a task or protected type. In the latter case,
3432 -- the selector must denote a visible entry.
3434 procedure Analyze_Selected_Component (N : Node_Id) is
3435 Name : constant Node_Id := Prefix (N);
3436 Sel : constant Node_Id := Selector_Name (N);
3439 Has_Candidate : Boolean := False;
3442 Pent : Entity_Id := Empty;
3443 Prefix_Type : Entity_Id;
3445 Type_To_Use : Entity_Id;
3446 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
3447 -- a class-wide type, we use its root type, whose components are
3448 -- present in the class-wide type.
3450 Is_Single_Concurrent_Object : Boolean;
3451 -- Set True if the prefix is a single task or a single protected object
3453 procedure Find_Component_In_Instance (Rec : Entity_Id);
3454 -- In an instance, a component of a private extension may not be visible
3455 -- while it was visible in the generic. Search candidate scope for a
3456 -- component with the proper identifier. This is only done if all other
3457 -- searches have failed. When the match is found (it always will be),
3458 -- the Etype of both N and Sel are set from this component, and the
3459 -- entity of Sel is set to reference this component.
3461 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
3462 -- It is known that the parent of N denotes a subprogram call. Comp
3463 -- is an overloadable component of the concurrent type of the prefix.
3464 -- Determine whether all formals of the parent of N and Comp are mode
3465 -- conformant. If the parent node is not analyzed yet it may be an
3466 -- indexed component rather than a function call.
3468 --------------------------------
3469 -- Find_Component_In_Instance --
3470 --------------------------------
3472 procedure Find_Component_In_Instance (Rec : Entity_Id) is
3476 Comp := First_Component (Rec);
3477 while Present (Comp) loop
3478 if Chars (Comp) = Chars (Sel) then
3479 Set_Entity_With_Style_Check (Sel, Comp);
3480 Set_Etype (Sel, Etype (Comp));
3481 Set_Etype (N, Etype (Comp));
3485 Next_Component (Comp);
3488 -- This must succeed because code was legal in the generic
3490 raise Program_Error;
3491 end Find_Component_In_Instance;
3493 ------------------------------
3494 -- Has_Mode_Conformant_Spec --
3495 ------------------------------
3497 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
3498 Comp_Param : Entity_Id;
3500 Param_Typ : Entity_Id;
3503 Comp_Param := First_Formal (Comp);
3505 if Nkind (Parent (N)) = N_Indexed_Component then
3506 Param := First (Expressions (Parent (N)));
3508 Param := First (Parameter_Associations (Parent (N)));
3511 while Present (Comp_Param)
3512 and then Present (Param)
3514 Param_Typ := Find_Parameter_Type (Param);
3516 if Present (Param_Typ)
3518 not Conforming_Types
3519 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3524 Next_Formal (Comp_Param);
3528 -- One of the specs has additional formals
3530 if Present (Comp_Param) or else Present (Param) then
3535 end Has_Mode_Conformant_Spec;
3537 -- Start of processing for Analyze_Selected_Component
3540 Set_Etype (N, Any_Type);
3542 if Is_Overloaded (Name) then
3543 Analyze_Overloaded_Selected_Component (N);
3546 elsif Etype (Name) = Any_Type then
3547 Set_Entity (Sel, Any_Id);
3548 Set_Etype (Sel, Any_Type);
3552 Prefix_Type := Etype (Name);
3555 if Is_Access_Type (Prefix_Type) then
3557 -- A RACW object can never be used as prefix of a selected component
3558 -- since that means it is dereferenced without being a controlling
3559 -- operand of a dispatching operation (RM E.2.2(16/1)). Before
3560 -- reporting an error, we must check whether this is actually a
3561 -- dispatching call in prefix form.
3563 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3564 and then Comes_From_Source (N)
3566 if Try_Object_Operation (N) then
3570 ("invalid dereference of a remote access-to-class-wide value",
3574 -- Normal case of selected component applied to access type
3577 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3579 if Is_Entity_Name (Name) then
3580 Pent := Entity (Name);
3581 elsif Nkind (Name) = N_Selected_Component
3582 and then Is_Entity_Name (Selector_Name (Name))
3584 Pent := Entity (Selector_Name (Name));
3587 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3590 -- If we have an explicit dereference of a remote access-to-class-wide
3591 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3592 -- have to check for the case of a prefix that is a controlling operand
3593 -- of a prefixed dispatching call, as the dereference is legal in that
3594 -- case. Normally this condition is checked in Validate_Remote_Access_
3595 -- To_Class_Wide_Type, but we have to defer the checking for selected
3596 -- component prefixes because of the prefixed dispatching call case.
3597 -- Note that implicit dereferences are checked for this just above.
3599 elsif Nkind (Name) = N_Explicit_Dereference
3600 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3601 and then Comes_From_Source (N)
3603 if Try_Object_Operation (N) then
3607 ("invalid dereference of a remote access-to-class-wide value",
3612 -- (Ada 2005): if the prefix is the limited view of a type, and
3613 -- the context already includes the full view, use the full view
3614 -- in what follows, either to retrieve a component of to find
3615 -- a primitive operation. If the prefix is an explicit dereference,
3616 -- set the type of the prefix to reflect this transformation.
3617 -- If the non-limited view is itself an incomplete type, get the
3618 -- full view if available.
3620 if Is_Incomplete_Type (Prefix_Type)
3621 and then From_With_Type (Prefix_Type)
3622 and then Present (Non_Limited_View (Prefix_Type))
3624 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3626 if Nkind (N) = N_Explicit_Dereference then
3627 Set_Etype (Prefix (N), Prefix_Type);
3630 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3631 and then From_With_Type (Prefix_Type)
3632 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3635 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3637 if Nkind (N) = N_Explicit_Dereference then
3638 Set_Etype (Prefix (N), Prefix_Type);
3642 if Ekind (Prefix_Type) = E_Private_Subtype then
3643 Prefix_Type := Base_Type (Prefix_Type);
3646 Type_To_Use := Prefix_Type;
3648 -- For class-wide types, use the entity list of the root type. This
3649 -- indirection is specially important for private extensions because
3650 -- only the root type get switched (not the class-wide type).
3652 if Is_Class_Wide_Type (Prefix_Type) then
3653 Type_To_Use := Root_Type (Prefix_Type);
3656 -- If the prefix is a single concurrent object, use its name in error
3657 -- messages, rather than that of its anonymous type.
3659 Is_Single_Concurrent_Object :=
3660 Is_Concurrent_Type (Prefix_Type)
3661 and then Is_Internal_Name (Chars (Prefix_Type))
3662 and then not Is_Derived_Type (Prefix_Type)
3663 and then Is_Entity_Name (Name);
3665 Comp := First_Entity (Type_To_Use);
3667 -- If the selector has an original discriminant, the node appears in
3668 -- an instance. Replace the discriminant with the corresponding one
3669 -- in the current discriminated type. For nested generics, this must
3670 -- be done transitively, so note the new original discriminant.
3672 if Nkind (Sel) = N_Identifier
3673 and then Present (Original_Discriminant (Sel))
3675 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3677 -- Mark entity before rewriting, for completeness and because
3678 -- subsequent semantic checks might examine the original node.
3680 Set_Entity (Sel, Comp);
3681 Rewrite (Selector_Name (N),
3682 New_Occurrence_Of (Comp, Sloc (N)));
3683 Set_Original_Discriminant (Selector_Name (N), Comp);
3684 Set_Etype (N, Etype (Comp));
3686 if Is_Access_Type (Etype (Name)) then
3687 Insert_Explicit_Dereference (Name);
3688 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3691 elsif Is_Record_Type (Prefix_Type) then
3693 -- Find component with given name
3695 while Present (Comp) loop
3696 if Chars (Comp) = Chars (Sel)
3697 and then Is_Visible_Component (Comp)
3699 Set_Entity_With_Style_Check (Sel, Comp);
3700 Set_Etype (Sel, Etype (Comp));
3702 if Ekind (Comp) = E_Discriminant then
3703 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3705 ("cannot reference discriminant of Unchecked_Union",
3709 if Is_Generic_Type (Prefix_Type)
3711 Is_Generic_Type (Root_Type (Prefix_Type))
3713 Set_Original_Discriminant (Sel, Comp);
3717 -- Resolve the prefix early otherwise it is not possible to
3718 -- build the actual subtype of the component: it may need
3719 -- to duplicate this prefix and duplication is only allowed
3720 -- on fully resolved expressions.
3724 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3725 -- subtypes in a package specification.
3728 -- limited with Pkg;
3730 -- type Acc_Inc is access Pkg.T;
3732 -- N : Natural := X.all.Comp; -- ERROR, limited view
3733 -- end Pkg; -- Comp is not visible
3735 if Nkind (Name) = N_Explicit_Dereference
3736 and then From_With_Type (Etype (Prefix (Name)))
3737 and then not Is_Potentially_Use_Visible (Etype (Name))
3738 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3739 N_Package_Specification
3742 ("premature usage of incomplete}", Prefix (Name),
3743 Etype (Prefix (Name)));
3746 -- We never need an actual subtype for the case of a selection
3747 -- for a indexed component of a non-packed array, since in
3748 -- this case gigi generates all the checks and can find the
3749 -- necessary bounds information.
3751 -- We also do not need an actual subtype for the case of a
3752 -- first, last, length, or range attribute applied to a
3753 -- non-packed array, since gigi can again get the bounds in
3754 -- these cases (gigi cannot handle the packed case, since it
3755 -- has the bounds of the packed array type, not the original
3756 -- bounds of the type). However, if the prefix is itself a
3757 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3758 -- as a dynamic-sized temporary, so we do generate an actual
3759 -- subtype for this case.
3761 Parent_N := Parent (N);
3763 if not Is_Packed (Etype (Comp))
3765 ((Nkind (Parent_N) = N_Indexed_Component
3766 and then Nkind (Name) /= N_Selected_Component)
3768 (Nkind (Parent_N) = N_Attribute_Reference
3769 and then (Attribute_Name (Parent_N) = Name_First
3771 Attribute_Name (Parent_N) = Name_Last
3773 Attribute_Name (Parent_N) = Name_Length
3775 Attribute_Name (Parent_N) = Name_Range)))
3777 Set_Etype (N, Etype (Comp));
3779 -- If full analysis is not enabled, we do not generate an
3780 -- actual subtype, because in the absence of expansion
3781 -- reference to a formal of a protected type, for example,
3782 -- will not be properly transformed, and will lead to
3783 -- out-of-scope references in gigi.
3785 -- In all other cases, we currently build an actual subtype.
3786 -- It seems likely that many of these cases can be avoided,
3787 -- but right now, the front end makes direct references to the
3788 -- bounds (e.g. in generating a length check), and if we do
3789 -- not make an actual subtype, we end up getting a direct
3790 -- reference to a discriminant, which will not do.
3792 elsif Full_Analysis then
3794 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3795 Insert_Action (N, Act_Decl);
3797 if No (Act_Decl) then
3798 Set_Etype (N, Etype (Comp));
3801 -- Component type depends on discriminants. Enter the
3802 -- main attributes of the subtype.
3805 Subt : constant Entity_Id :=
3806 Defining_Identifier (Act_Decl);
3809 Set_Etype (Subt, Base_Type (Etype (Comp)));
3810 Set_Ekind (Subt, Ekind (Etype (Comp)));
3811 Set_Etype (N, Subt);
3815 -- If Full_Analysis not enabled, just set the Etype
3818 Set_Etype (N, Etype (Comp));
3824 -- If the prefix is a private extension, check only the visible
3825 -- components of the partial view. This must include the tag,
3826 -- which can appear in expanded code in a tag check.
3828 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3829 and then Chars (Selector_Name (N)) /= Name_uTag
3831 exit when Comp = Last_Entity (Type_To_Use);
3837 -- Ada 2005 (AI-252): The selected component can be interpreted as
3838 -- a prefixed view of a subprogram. Depending on the context, this is
3839 -- either a name that can appear in a renaming declaration, or part
3840 -- of an enclosing call given in prefix form.
3842 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3843 -- selected component should resolve to a name.
3845 if Ada_Version >= Ada_2005
3846 and then Is_Tagged_Type (Prefix_Type)
3847 and then not Is_Concurrent_Type (Prefix_Type)
3849 if Nkind (Parent (N)) = N_Generic_Association
3850 or else Nkind (Parent (N)) = N_Requeue_Statement
3851 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3853 if Find_Primitive_Operation (N) then
3857 elsif Try_Object_Operation (N) then
3861 -- If the transformation fails, it will be necessary to redo the
3862 -- analysis with all errors enabled, to indicate candidate
3863 -- interpretations and reasons for each failure ???
3867 elsif Is_Private_Type (Prefix_Type) then
3869 -- Allow access only to discriminants of the type. If the type has
3870 -- no full view, gigi uses the parent type for the components, so we
3871 -- do the same here.
3873 if No (Full_View (Prefix_Type)) then
3874 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3875 Comp := First_Entity (Type_To_Use);
3878 while Present (Comp) loop
3879 if Chars (Comp) = Chars (Sel) then
3880 if Ekind (Comp) = E_Discriminant then
3881 Set_Entity_With_Style_Check (Sel, Comp);
3882 Generate_Reference (Comp, Sel);
3884 Set_Etype (Sel, Etype (Comp));
3885 Set_Etype (N, Etype (Comp));
3887 if Is_Generic_Type (Prefix_Type)
3888 or else Is_Generic_Type (Root_Type (Prefix_Type))
3890 Set_Original_Discriminant (Sel, Comp);
3893 -- Before declaring an error, check whether this is tagged
3894 -- private type and a call to a primitive operation.
3896 elsif Ada_Version >= Ada_2005
3897 and then Is_Tagged_Type (Prefix_Type)
3898 and then Try_Object_Operation (N)
3903 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3904 Error_Msg_NE ("invisible selector& for }", N, Sel);
3905 Set_Entity (Sel, Any_Id);
3906 Set_Etype (N, Any_Type);
3915 elsif Is_Concurrent_Type (Prefix_Type) then
3917 -- Find visible operation with given name. For a protected type,
3918 -- the possible candidates are discriminants, entries or protected
3919 -- procedures. For a task type, the set can only include entries or
3920 -- discriminants if the task type is not an enclosing scope. If it
3921 -- is an enclosing scope (e.g. in an inner task) then all entities
3922 -- are visible, but the prefix must denote the enclosing scope, i.e.
3923 -- can only be a direct name or an expanded name.
3925 Set_Etype (Sel, Any_Type);
3926 In_Scope := In_Open_Scopes (Prefix_Type);
3928 while Present (Comp) loop
3929 if Chars (Comp) = Chars (Sel) then
3930 if Is_Overloadable (Comp) then
3931 Add_One_Interp (Sel, Comp, Etype (Comp));
3933 -- If the prefix is tagged, the correct interpretation may
3934 -- lie in the primitive or class-wide operations of the
3935 -- type. Perform a simple conformance check to determine
3936 -- whether Try_Object_Operation should be invoked even if
3937 -- a visible entity is found.
3939 if Is_Tagged_Type (Prefix_Type)
3941 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3943 N_Indexed_Component)
3944 and then Has_Mode_Conformant_Spec (Comp)
3946 Has_Candidate := True;
3949 -- Note: a selected component may not denote a component of a
3950 -- protected type (4.1.3(7)).
3952 elsif Ekind_In (Comp, E_Discriminant, E_Entry_Family)
3954 and then not Is_Protected_Type (Prefix_Type)
3955 and then Is_Entity_Name (Name))
3957 Set_Entity_With_Style_Check (Sel, Comp);
3958 Generate_Reference (Comp, Sel);
3964 Set_Etype (Sel, Etype (Comp));
3965 Set_Etype (N, Etype (Comp));
3967 if Ekind (Comp) = E_Discriminant then
3968 Set_Original_Discriminant (Sel, Comp);
3971 -- For access type case, introduce explicit dereference for
3972 -- more uniform treatment of entry calls.
3974 if Is_Access_Type (Etype (Name)) then
3975 Insert_Explicit_Dereference (Name);
3977 (Warn_On_Dereference, "?implicit dereference", N);
3983 exit when not In_Scope
3985 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3988 -- If there is no visible entity with the given name or none of the
3989 -- visible entities are plausible interpretations, check whether
3990 -- there is some other primitive operation with that name.
3992 if Ada_Version >= Ada_2005
3993 and then Is_Tagged_Type (Prefix_Type)
3995 if (Etype (N) = Any_Type
3996 or else not Has_Candidate)
3997 and then Try_Object_Operation (N)
4001 -- If the context is not syntactically a procedure call, it
4002 -- may be a call to a primitive function declared outside of
4003 -- the synchronized type.
4005 -- If the context is a procedure call, there might still be
4006 -- an overloading between an entry and a primitive procedure
4007 -- declared outside of the synchronized type, called in prefix
4008 -- notation. This is harder to disambiguate because in one case
4009 -- the controlling formal is implicit ???
4011 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
4012 and then Nkind (Parent (N)) /= N_Indexed_Component
4013 and then Try_Object_Operation (N)
4019 if Etype (N) = Any_Type and then Is_Protected_Type (Prefix_Type) then
4020 -- Case of a prefix of a protected type: selector might denote
4021 -- an invisible private component.
4023 Comp := First_Private_Entity (Base_Type (Prefix_Type));
4024 while Present (Comp) and then Chars (Comp) /= Chars (Sel) loop
4028 if Present (Comp) then
4029 if Is_Single_Concurrent_Object then
4030 Error_Msg_Node_2 := Entity (Name);
4031 Error_Msg_NE ("invisible selector& for &", N, Sel);
4034 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4035 Error_Msg_NE ("invisible selector& for }", N, Sel);
4041 Set_Is_Overloaded (N, Is_Overloaded (Sel));
4046 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
4049 -- If N still has no type, the component is not defined in the prefix
4051 if Etype (N) = Any_Type then
4053 if Is_Single_Concurrent_Object then
4054 Error_Msg_Node_2 := Entity (Name);
4055 Error_Msg_NE ("no selector& for&", N, Sel);
4057 Check_Misspelled_Selector (Type_To_Use, Sel);
4059 elsif Is_Generic_Type (Prefix_Type)
4060 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
4061 and then Prefix_Type /= Etype (Prefix_Type)
4062 and then Is_Record_Type (Etype (Prefix_Type))
4064 -- If this is a derived formal type, the parent may have
4065 -- different visibility at this point. Try for an inherited
4066 -- component before reporting an error.
4068 Set_Etype (Prefix (N), Etype (Prefix_Type));
4069 Analyze_Selected_Component (N);
4072 -- Similarly, if this is the actual for a formal derived type, the
4073 -- component inherited from the generic parent may not be visible
4074 -- in the actual, but the selected component is legal.
4076 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
4077 and then Is_Generic_Actual_Type (Prefix_Type)
4078 and then Present (Full_View (Prefix_Type))
4081 Find_Component_In_Instance
4082 (Generic_Parent_Type (Parent (Prefix_Type)));
4085 -- Finally, the formal and the actual may be private extensions,
4086 -- but the generic is declared in a child unit of the parent, and
4087 -- an addtional step is needed to retrieve the proper scope.
4090 and then Present (Parent_Subtype (Etype (Base_Type (Prefix_Type))))
4092 Find_Component_In_Instance
4093 (Parent_Subtype (Etype (Base_Type (Prefix_Type))));
4096 -- Component not found, specialize error message when appropriate
4099 if Ekind (Prefix_Type) = E_Record_Subtype then
4101 -- Check whether this is a component of the base type which
4102 -- is absent from a statically constrained subtype. This will
4103 -- raise constraint error at run time, but is not a compile-
4104 -- time error. When the selector is illegal for base type as
4105 -- well fall through and generate a compilation error anyway.
4107 Comp := First_Component (Base_Type (Prefix_Type));
4108 while Present (Comp) loop
4109 if Chars (Comp) = Chars (Sel)
4110 and then Is_Visible_Component (Comp)
4112 Set_Entity_With_Style_Check (Sel, Comp);
4113 Generate_Reference (Comp, Sel);
4114 Set_Etype (Sel, Etype (Comp));
4115 Set_Etype (N, Etype (Comp));
4117 -- Emit appropriate message. Gigi will replace the
4118 -- node subsequently with the appropriate Raise.
4120 Apply_Compile_Time_Constraint_Error
4121 (N, "component not present in }?",
4122 CE_Discriminant_Check_Failed,
4123 Ent => Prefix_Type, Rep => False);
4124 Set_Raises_Constraint_Error (N);
4128 Next_Component (Comp);
4133 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4134 Error_Msg_NE ("no selector& for}", N, Sel);
4136 Check_Misspelled_Selector (Type_To_Use, Sel);
4139 Set_Entity (Sel, Any_Id);
4140 Set_Etype (Sel, Any_Type);
4142 end Analyze_Selected_Component;
4144 ---------------------------
4145 -- Analyze_Short_Circuit --
4146 ---------------------------
4148 procedure Analyze_Short_Circuit (N : Node_Id) is
4149 L : constant Node_Id := Left_Opnd (N);
4150 R : constant Node_Id := Right_Opnd (N);
4155 Analyze_Expression (L);
4156 Analyze_Expression (R);
4157 Set_Etype (N, Any_Type);
4159 if not Is_Overloaded (L) then
4160 if Root_Type (Etype (L)) = Standard_Boolean
4161 and then Has_Compatible_Type (R, Etype (L))
4163 Add_One_Interp (N, Etype (L), Etype (L));
4167 Get_First_Interp (L, Ind, It);
4168 while Present (It.Typ) loop
4169 if Root_Type (It.Typ) = Standard_Boolean
4170 and then Has_Compatible_Type (R, It.Typ)
4172 Add_One_Interp (N, It.Typ, It.Typ);
4175 Get_Next_Interp (Ind, It);
4179 -- Here we have failed to find an interpretation. Clearly we know that
4180 -- it is not the case that both operands can have an interpretation of
4181 -- Boolean, but this is by far the most likely intended interpretation.
4182 -- So we simply resolve both operands as Booleans, and at least one of
4183 -- these resolutions will generate an error message, and we do not need
4184 -- to give another error message on the short circuit operation itself.
4186 if Etype (N) = Any_Type then
4187 Resolve (L, Standard_Boolean);
4188 Resolve (R, Standard_Boolean);
4189 Set_Etype (N, Standard_Boolean);
4191 end Analyze_Short_Circuit;
4197 procedure Analyze_Slice (N : Node_Id) is
4198 P : constant Node_Id := Prefix (N);
4199 D : constant Node_Id := Discrete_Range (N);
4200 Array_Type : Entity_Id;
4202 procedure Analyze_Overloaded_Slice;
4203 -- If the prefix is overloaded, select those interpretations that
4204 -- yield a one-dimensional array type.
4206 ------------------------------
4207 -- Analyze_Overloaded_Slice --
4208 ------------------------------
4210 procedure Analyze_Overloaded_Slice is
4216 Set_Etype (N, Any_Type);
4218 Get_First_Interp (P, I, It);
4219 while Present (It.Nam) loop
4222 if Is_Access_Type (Typ) then
4223 Typ := Designated_Type (Typ);
4224 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4227 if Is_Array_Type (Typ)
4228 and then Number_Dimensions (Typ) = 1
4229 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
4231 Add_One_Interp (N, Typ, Typ);
4234 Get_Next_Interp (I, It);
4237 if Etype (N) = Any_Type then
4238 Error_Msg_N ("expect array type in prefix of slice", N);
4240 end Analyze_Overloaded_Slice;
4242 -- Start of processing for Analyze_Slice
4248 if Is_Overloaded (P) then
4249 Analyze_Overloaded_Slice;
4252 Array_Type := Etype (P);
4253 Set_Etype (N, Any_Type);
4255 if Is_Access_Type (Array_Type) then
4256 Array_Type := Designated_Type (Array_Type);
4257 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4260 if not Is_Array_Type (Array_Type) then
4261 Wrong_Type (P, Any_Array);
4263 elsif Number_Dimensions (Array_Type) > 1 then
4265 ("type is not one-dimensional array in slice prefix", N);
4268 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
4270 Wrong_Type (D, Etype (First_Index (Array_Type)));
4273 Set_Etype (N, Array_Type);
4278 -----------------------------
4279 -- Analyze_Type_Conversion --
4280 -----------------------------
4282 procedure Analyze_Type_Conversion (N : Node_Id) is
4283 Expr : constant Node_Id := Expression (N);
4287 -- If Conversion_OK is set, then the Etype is already set, and the
4288 -- only processing required is to analyze the expression. This is
4289 -- used to construct certain "illegal" conversions which are not
4290 -- allowed by Ada semantics, but can be handled OK by Gigi, see
4291 -- Sinfo for further details.
4293 if Conversion_OK (N) then
4298 -- Otherwise full type analysis is required, as well as some semantic
4299 -- checks to make sure the argument of the conversion is appropriate.
4301 Find_Type (Subtype_Mark (N));
4302 T := Entity (Subtype_Mark (N));
4304 Check_Fully_Declared (T, N);
4305 Analyze_Expression (Expr);
4306 Validate_Remote_Type_Type_Conversion (N);
4308 -- Only remaining step is validity checks on the argument. These
4309 -- are skipped if the conversion does not come from the source.
4311 if not Comes_From_Source (N) then
4314 -- If there was an error in a generic unit, no need to replicate the
4315 -- error message. Conversely, constant-folding in the generic may
4316 -- transform the argument of a conversion into a string literal, which
4317 -- is legal. Therefore the following tests are not performed in an
4320 elsif In_Instance then
4323 elsif Nkind (Expr) = N_Null then
4324 Error_Msg_N ("argument of conversion cannot be null", N);
4325 Error_Msg_N ("\use qualified expression instead", N);
4326 Set_Etype (N, Any_Type);
4328 elsif Nkind (Expr) = N_Aggregate then
4329 Error_Msg_N ("argument of conversion cannot be aggregate", N);
4330 Error_Msg_N ("\use qualified expression instead", N);
4332 elsif Nkind (Expr) = N_Allocator then
4333 Error_Msg_N ("argument of conversion cannot be an allocator", N);
4334 Error_Msg_N ("\use qualified expression instead", N);
4336 elsif Nkind (Expr) = N_String_Literal then
4337 Error_Msg_N ("argument of conversion cannot be string literal", N);
4338 Error_Msg_N ("\use qualified expression instead", N);
4340 elsif Nkind (Expr) = N_Character_Literal then
4341 if Ada_Version = Ada_83 then
4344 Error_Msg_N ("argument of conversion cannot be character literal",
4346 Error_Msg_N ("\use qualified expression instead", N);
4349 elsif Nkind (Expr) = N_Attribute_Reference
4351 (Attribute_Name (Expr) = Name_Access or else
4352 Attribute_Name (Expr) = Name_Unchecked_Access or else
4353 Attribute_Name (Expr) = Name_Unrestricted_Access)
4355 Error_Msg_N ("argument of conversion cannot be access", N);
4356 Error_Msg_N ("\use qualified expression instead", N);
4358 end Analyze_Type_Conversion;
4360 ----------------------
4361 -- Analyze_Unary_Op --
4362 ----------------------
4364 procedure Analyze_Unary_Op (N : Node_Id) is
4365 R : constant Node_Id := Right_Opnd (N);
4366 Op_Id : Entity_Id := Entity (N);
4369 Set_Etype (N, Any_Type);
4370 Candidate_Type := Empty;
4372 Analyze_Expression (R);
4374 if Present (Op_Id) then
4375 if Ekind (Op_Id) = E_Operator then
4376 Find_Unary_Types (R, Op_Id, N);
4378 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4382 Op_Id := Get_Name_Entity_Id (Chars (N));
4383 while Present (Op_Id) loop
4384 if Ekind (Op_Id) = E_Operator then
4385 if No (Next_Entity (First_Entity (Op_Id))) then
4386 Find_Unary_Types (R, Op_Id, N);
4389 elsif Is_Overloadable (Op_Id) then
4390 Analyze_User_Defined_Unary_Op (N, Op_Id);
4393 Op_Id := Homonym (Op_Id);
4398 end Analyze_Unary_Op;
4400 ----------------------------------
4401 -- Analyze_Unchecked_Expression --
4402 ----------------------------------
4404 procedure Analyze_Unchecked_Expression (N : Node_Id) is
4406 Analyze (Expression (N), Suppress => All_Checks);
4407 Set_Etype (N, Etype (Expression (N)));
4408 Save_Interps (Expression (N), N);
4409 end Analyze_Unchecked_Expression;
4411 ---------------------------------------
4412 -- Analyze_Unchecked_Type_Conversion --
4413 ---------------------------------------
4415 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
4417 Find_Type (Subtype_Mark (N));
4418 Analyze_Expression (Expression (N));
4419 Set_Etype (N, Entity (Subtype_Mark (N)));
4420 end Analyze_Unchecked_Type_Conversion;
4422 ------------------------------------
4423 -- Analyze_User_Defined_Binary_Op --
4424 ------------------------------------
4426 procedure Analyze_User_Defined_Binary_Op
4431 -- Only do analysis if the operator Comes_From_Source, since otherwise
4432 -- the operator was generated by the expander, and all such operators
4433 -- always refer to the operators in package Standard.
4435 if Comes_From_Source (N) then
4437 F1 : constant Entity_Id := First_Formal (Op_Id);
4438 F2 : constant Entity_Id := Next_Formal (F1);
4441 -- Verify that Op_Id is a visible binary function. Note that since
4442 -- we know Op_Id is overloaded, potentially use visible means use
4443 -- visible for sure (RM 9.4(11)).
4445 if Ekind (Op_Id) = E_Function
4446 and then Present (F2)
4447 and then (Is_Immediately_Visible (Op_Id)
4448 or else Is_Potentially_Use_Visible (Op_Id))
4449 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
4450 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
4452 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4454 -- If the left operand is overloaded, indicate that the
4455 -- current type is a viable candidate. This is redundant
4456 -- in most cases, but for equality and comparison operators
4457 -- where the context does not impose a type on the operands,
4458 -- setting the proper type is necessary to avoid subsequent
4459 -- ambiguities during resolution, when both user-defined and
4460 -- predefined operators may be candidates.
4462 if Is_Overloaded (Left_Opnd (N)) then
4463 Set_Etype (Left_Opnd (N), Etype (F1));
4466 if Debug_Flag_E then
4467 Write_Str ("user defined operator ");
4468 Write_Name (Chars (Op_Id));
4469 Write_Str (" on node ");
4470 Write_Int (Int (N));
4476 end Analyze_User_Defined_Binary_Op;
4478 -----------------------------------
4479 -- Analyze_User_Defined_Unary_Op --
4480 -----------------------------------
4482 procedure Analyze_User_Defined_Unary_Op
4487 -- Only do analysis if the operator Comes_From_Source, since otherwise
4488 -- the operator was generated by the expander, and all such operators
4489 -- always refer to the operators in package Standard.
4491 if Comes_From_Source (N) then
4493 F : constant Entity_Id := First_Formal (Op_Id);
4496 -- Verify that Op_Id is a visible unary function. Note that since
4497 -- we know Op_Id is overloaded, potentially use visible means use
4498 -- visible for sure (RM 9.4(11)).
4500 if Ekind (Op_Id) = E_Function
4501 and then No (Next_Formal (F))
4502 and then (Is_Immediately_Visible (Op_Id)
4503 or else Is_Potentially_Use_Visible (Op_Id))
4504 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
4506 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4510 end Analyze_User_Defined_Unary_Op;
4512 ---------------------------
4513 -- Check_Arithmetic_Pair --
4514 ---------------------------
4516 procedure Check_Arithmetic_Pair
4517 (T1, T2 : Entity_Id;
4521 Op_Name : constant Name_Id := Chars (Op_Id);
4523 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
4524 -- Check whether the fixed-point type Typ has a user-defined operator
4525 -- (multiplication or division) that should hide the corresponding
4526 -- predefined operator. Used to implement Ada 2005 AI-264, to make
4527 -- such operators more visible and therefore useful.
4529 -- If the name of the operation is an expanded name with prefix
4530 -- Standard, the predefined universal fixed operator is available,
4531 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
4533 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
4534 -- Get specific type (i.e. non-universal type if there is one)
4540 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
4541 Bas : constant Entity_Id := Base_Type (Typ);
4547 -- If the universal_fixed operation is given explicitly the rule
4548 -- concerning primitive operations of the type do not apply.
4550 if Nkind (N) = N_Function_Call
4551 and then Nkind (Name (N)) = N_Expanded_Name
4552 and then Entity (Prefix (Name (N))) = Standard_Standard
4557 -- The operation is treated as primitive if it is declared in the
4558 -- same scope as the type, and therefore on the same entity chain.
4560 Ent := Next_Entity (Typ);
4561 while Present (Ent) loop
4562 if Chars (Ent) = Chars (Op) then
4563 F1 := First_Formal (Ent);
4564 F2 := Next_Formal (F1);
4566 -- The operation counts as primitive if either operand or
4567 -- result are of the given base type, and both operands are
4568 -- fixed point types.
4570 if (Base_Type (Etype (F1)) = Bas
4571 and then Is_Fixed_Point_Type (Etype (F2)))
4574 (Base_Type (Etype (F2)) = Bas
4575 and then Is_Fixed_Point_Type (Etype (F1)))
4578 (Base_Type (Etype (Ent)) = Bas
4579 and then Is_Fixed_Point_Type (Etype (F1))
4580 and then Is_Fixed_Point_Type (Etype (F2)))
4596 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4598 if T1 = Universal_Integer or else T1 = Universal_Real then
4599 return Base_Type (T2);
4601 return Base_Type (T1);
4605 -- Start of processing for Check_Arithmetic_Pair
4608 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4610 if Is_Numeric_Type (T1)
4611 and then Is_Numeric_Type (T2)
4612 and then (Covers (T1 => T1, T2 => T2)
4614 Covers (T1 => T2, T2 => T1))
4616 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4619 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4621 if Is_Fixed_Point_Type (T1)
4622 and then (Is_Fixed_Point_Type (T2)
4623 or else T2 = Universal_Real)
4625 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4626 -- and no further processing is required (this is the case of an
4627 -- operator constructed by Exp_Fixd for a fixed point operation)
4628 -- Otherwise add one interpretation with universal fixed result
4629 -- If the operator is given in functional notation, it comes
4630 -- from source and Fixed_As_Integer cannot apply.
4632 if (Nkind (N) not in N_Op
4633 or else not Treat_Fixed_As_Integer (N))
4635 (not Has_Fixed_Op (T1, Op_Id)
4636 or else Nkind (Parent (N)) = N_Type_Conversion)
4638 Add_One_Interp (N, Op_Id, Universal_Fixed);
4641 elsif Is_Fixed_Point_Type (T2)
4642 and then (Nkind (N) not in N_Op
4643 or else not Treat_Fixed_As_Integer (N))
4644 and then T1 = Universal_Real
4646 (not Has_Fixed_Op (T1, Op_Id)
4647 or else Nkind (Parent (N)) = N_Type_Conversion)
4649 Add_One_Interp (N, Op_Id, Universal_Fixed);
4651 elsif Is_Numeric_Type (T1)
4652 and then Is_Numeric_Type (T2)
4653 and then (Covers (T1 => T1, T2 => T2)
4655 Covers (T1 => T2, T2 => T1))
4657 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4659 elsif Is_Fixed_Point_Type (T1)
4660 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4661 or else T2 = Universal_Integer)
4663 Add_One_Interp (N, Op_Id, T1);
4665 elsif T2 = Universal_Real
4666 and then Base_Type (T1) = Base_Type (Standard_Integer)
4667 and then Op_Name = Name_Op_Multiply
4669 Add_One_Interp (N, Op_Id, Any_Fixed);
4671 elsif T1 = Universal_Real
4672 and then Base_Type (T2) = Base_Type (Standard_Integer)
4674 Add_One_Interp (N, Op_Id, Any_Fixed);
4676 elsif Is_Fixed_Point_Type (T2)
4677 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4678 or else T1 = Universal_Integer)
4679 and then Op_Name = Name_Op_Multiply
4681 Add_One_Interp (N, Op_Id, T2);
4683 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4684 Add_One_Interp (N, Op_Id, T1);
4686 elsif T2 = Universal_Real
4687 and then T1 = Universal_Integer
4688 and then Op_Name = Name_Op_Multiply
4690 Add_One_Interp (N, Op_Id, T2);
4693 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4695 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4696 -- set does not require any special processing, since the Etype is
4697 -- already set (case of operation constructed by Exp_Fixed).
4699 if Is_Integer_Type (T1)
4700 and then (Covers (T1 => T1, T2 => T2)
4702 Covers (T1 => T2, T2 => T1))
4704 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4707 elsif Op_Name = Name_Op_Expon then
4708 if Is_Numeric_Type (T1)
4709 and then not Is_Fixed_Point_Type (T1)
4710 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4711 or else T2 = Universal_Integer)
4713 Add_One_Interp (N, Op_Id, Base_Type (T1));
4716 else pragma Assert (Nkind (N) in N_Op_Shift);
4718 -- If not one of the predefined operators, the node may be one
4719 -- of the intrinsic functions. Its kind is always specific, and
4720 -- we can use it directly, rather than the name of the operation.
4722 if Is_Integer_Type (T1)
4723 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4724 or else T2 = Universal_Integer)
4726 Add_One_Interp (N, Op_Id, Base_Type (T1));
4729 end Check_Arithmetic_Pair;
4731 -------------------------------
4732 -- Check_Misspelled_Selector --
4733 -------------------------------
4735 procedure Check_Misspelled_Selector
4736 (Prefix : Entity_Id;
4739 Max_Suggestions : constant := 2;
4740 Nr_Of_Suggestions : Natural := 0;
4742 Suggestion_1 : Entity_Id := Empty;
4743 Suggestion_2 : Entity_Id := Empty;
4748 -- All the components of the prefix of selector Sel are matched
4749 -- against Sel and a count is maintained of possible misspellings.
4750 -- When at the end of the analysis there are one or two (not more!)
4751 -- possible misspellings, these misspellings will be suggested as
4752 -- possible correction.
4754 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4756 -- Concurrent types should be handled as well ???
4761 Comp := First_Entity (Prefix);
4762 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4763 if Is_Visible_Component (Comp) then
4764 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4765 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4767 case Nr_Of_Suggestions is
4768 when 1 => Suggestion_1 := Comp;
4769 when 2 => Suggestion_2 := Comp;
4770 when others => exit;
4775 Comp := Next_Entity (Comp);
4778 -- Report at most two suggestions
4780 if Nr_Of_Suggestions = 1 then
4781 Error_Msg_NE -- CODEFIX
4782 ("\possible misspelling of&", Sel, Suggestion_1);
4784 elsif Nr_Of_Suggestions = 2 then
4785 Error_Msg_Node_2 := Suggestion_2;
4786 Error_Msg_NE -- CODEFIX
4787 ("\possible misspelling of& or&", Sel, Suggestion_1);
4789 end Check_Misspelled_Selector;
4791 ----------------------
4792 -- Defined_In_Scope --
4793 ----------------------
4795 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4797 S1 : constant Entity_Id := Scope (Base_Type (T));
4800 or else (S1 = System_Aux_Id and then S = Scope (S1));
4801 end Defined_In_Scope;
4807 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4813 Void_Interp_Seen : Boolean := False;
4816 pragma Warnings (Off, Boolean);
4819 if Ada_Version >= Ada_2005 then
4820 Actual := First_Actual (N);
4821 while Present (Actual) loop
4823 -- Ada 2005 (AI-50217): Post an error in case of premature
4824 -- usage of an entity from the limited view.
4826 if not Analyzed (Etype (Actual))
4827 and then From_With_Type (Etype (Actual))
4829 Error_Msg_Qual_Level := 1;
4831 ("missing with_clause for scope of imported type&",
4832 Actual, Etype (Actual));
4833 Error_Msg_Qual_Level := 0;
4836 Next_Actual (Actual);
4840 -- Analyze each candidate call again, with full error reporting
4844 ("no candidate interpretations match the actuals:!", Nam);
4845 Err_Mode := All_Errors_Mode;
4846 All_Errors_Mode := True;
4848 -- If this is a call to an operation of a concurrent type,
4849 -- the failed interpretations have been removed from the
4850 -- name. Recover them to provide full diagnostics.
4852 if Nkind (Parent (Nam)) = N_Selected_Component then
4853 Set_Entity (Nam, Empty);
4854 New_Nam := New_Copy_Tree (Parent (Nam));
4855 Set_Is_Overloaded (New_Nam, False);
4856 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4857 Set_Parent (New_Nam, Parent (Parent (Nam)));
4858 Analyze_Selected_Component (New_Nam);
4859 Get_First_Interp (Selector_Name (New_Nam), X, It);
4861 Get_First_Interp (Nam, X, It);
4864 while Present (It.Nam) loop
4865 if Etype (It.Nam) = Standard_Void_Type then
4866 Void_Interp_Seen := True;
4869 Analyze_One_Call (N, It.Nam, True, Success);
4870 Get_Next_Interp (X, It);
4873 if Nkind (N) = N_Function_Call then
4874 Get_First_Interp (Nam, X, It);
4875 while Present (It.Nam) loop
4876 if Ekind_In (It.Nam, E_Function, E_Operator) then
4879 Get_Next_Interp (X, It);
4883 -- If all interpretations are procedures, this deserves a
4884 -- more precise message. Ditto if this appears as the prefix
4885 -- of a selected component, which may be a lexical error.
4888 ("\context requires function call, found procedure name", Nam);
4890 if Nkind (Parent (N)) = N_Selected_Component
4891 and then N = Prefix (Parent (N))
4893 Error_Msg_N -- CODEFIX
4894 ("\period should probably be semicolon", Parent (N));
4897 elsif Nkind (N) = N_Procedure_Call_Statement
4898 and then not Void_Interp_Seen
4901 "\function name found in procedure call", Nam);
4904 All_Errors_Mode := Err_Mode;
4907 ---------------------------
4908 -- Find_Arithmetic_Types --
4909 ---------------------------
4911 procedure Find_Arithmetic_Types
4916 Index1 : Interp_Index;
4917 Index2 : Interp_Index;
4921 procedure Check_Right_Argument (T : Entity_Id);
4922 -- Check right operand of operator
4924 --------------------------
4925 -- Check_Right_Argument --
4926 --------------------------
4928 procedure Check_Right_Argument (T : Entity_Id) is
4930 if not Is_Overloaded (R) then
4931 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4933 Get_First_Interp (R, Index2, It2);
4934 while Present (It2.Typ) loop
4935 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4936 Get_Next_Interp (Index2, It2);
4939 end Check_Right_Argument;
4941 -- Start of processing for Find_Arithmetic_Types
4944 if not Is_Overloaded (L) then
4945 Check_Right_Argument (Etype (L));
4948 Get_First_Interp (L, Index1, It1);
4949 while Present (It1.Typ) loop
4950 Check_Right_Argument (It1.Typ);
4951 Get_Next_Interp (Index1, It1);
4955 end Find_Arithmetic_Types;
4957 ------------------------
4958 -- Find_Boolean_Types --
4959 ------------------------
4961 procedure Find_Boolean_Types
4966 Index : Interp_Index;
4969 procedure Check_Numeric_Argument (T : Entity_Id);
4970 -- Special case for logical operations one of whose operands is an
4971 -- integer literal. If both are literal the result is any modular type.
4973 ----------------------------
4974 -- Check_Numeric_Argument --
4975 ----------------------------
4977 procedure Check_Numeric_Argument (T : Entity_Id) is
4979 if T = Universal_Integer then
4980 Add_One_Interp (N, Op_Id, Any_Modular);
4982 elsif Is_Modular_Integer_Type (T) then
4983 Add_One_Interp (N, Op_Id, T);
4985 end Check_Numeric_Argument;
4987 -- Start of processing for Find_Boolean_Types
4990 if not Is_Overloaded (L) then
4991 if Etype (L) = Universal_Integer
4992 or else Etype (L) = Any_Modular
4994 if not Is_Overloaded (R) then
4995 Check_Numeric_Argument (Etype (R));
4998 Get_First_Interp (R, Index, It);
4999 while Present (It.Typ) loop
5000 Check_Numeric_Argument (It.Typ);
5001 Get_Next_Interp (Index, It);
5005 -- If operands are aggregates, we must assume that they may be
5006 -- boolean arrays, and leave disambiguation for the second pass.
5007 -- If only one is an aggregate, verify that the other one has an
5008 -- interpretation as a boolean array
5010 elsif Nkind (L) = N_Aggregate then
5011 if Nkind (R) = N_Aggregate then
5012 Add_One_Interp (N, Op_Id, Etype (L));
5014 elsif not Is_Overloaded (R) then
5015 if Valid_Boolean_Arg (Etype (R)) then
5016 Add_One_Interp (N, Op_Id, Etype (R));
5020 Get_First_Interp (R, Index, It);
5021 while Present (It.Typ) loop
5022 if Valid_Boolean_Arg (It.Typ) then
5023 Add_One_Interp (N, Op_Id, It.Typ);
5026 Get_Next_Interp (Index, It);
5030 elsif Valid_Boolean_Arg (Etype (L))
5031 and then Has_Compatible_Type (R, Etype (L))
5033 Add_One_Interp (N, Op_Id, Etype (L));
5037 Get_First_Interp (L, Index, It);
5038 while Present (It.Typ) loop
5039 if Valid_Boolean_Arg (It.Typ)
5040 and then Has_Compatible_Type (R, It.Typ)
5042 Add_One_Interp (N, Op_Id, It.Typ);
5045 Get_Next_Interp (Index, It);
5048 end Find_Boolean_Types;
5050 ---------------------------
5051 -- Find_Comparison_Types --
5052 ---------------------------
5054 procedure Find_Comparison_Types
5059 Index : Interp_Index;
5061 Found : Boolean := False;
5064 Scop : Entity_Id := Empty;
5066 procedure Try_One_Interp (T1 : Entity_Id);
5067 -- Routine to try one proposed interpretation. Note that the context
5068 -- of the operator plays no role in resolving the arguments, so that
5069 -- if there is more than one interpretation of the operands that is
5070 -- compatible with comparison, the operation is ambiguous.
5072 --------------------
5073 -- Try_One_Interp --
5074 --------------------
5076 procedure Try_One_Interp (T1 : Entity_Id) is
5079 -- If the operator is an expanded name, then the type of the operand
5080 -- must be defined in the corresponding scope. If the type is
5081 -- universal, the context will impose the correct type.
5084 and then not Defined_In_Scope (T1, Scop)
5085 and then T1 /= Universal_Integer
5086 and then T1 /= Universal_Real
5087 and then T1 /= Any_String
5088 and then T1 /= Any_Composite
5093 if Valid_Comparison_Arg (T1)
5094 and then Has_Compatible_Type (R, T1)
5097 and then Base_Type (T1) /= Base_Type (T_F)
5099 It := Disambiguate (L, I_F, Index, Any_Type);
5101 if It = No_Interp then
5102 Ambiguous_Operands (N);
5103 Set_Etype (L, Any_Type);
5117 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5122 -- Start of processing for Find_Comparison_Types
5125 -- If left operand is aggregate, the right operand has to
5126 -- provide a usable type for it.
5128 if Nkind (L) = N_Aggregate
5129 and then Nkind (R) /= N_Aggregate
5131 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5135 if Nkind (N) = N_Function_Call
5136 and then Nkind (Name (N)) = N_Expanded_Name
5138 Scop := Entity (Prefix (Name (N)));
5140 -- The prefix may be a package renaming, and the subsequent test
5141 -- requires the original package.
5143 if Ekind (Scop) = E_Package
5144 and then Present (Renamed_Entity (Scop))
5146 Scop := Renamed_Entity (Scop);
5147 Set_Entity (Prefix (Name (N)), Scop);
5151 if not Is_Overloaded (L) then
5152 Try_One_Interp (Etype (L));
5155 Get_First_Interp (L, Index, It);
5156 while Present (It.Typ) loop
5157 Try_One_Interp (It.Typ);
5158 Get_Next_Interp (Index, It);
5161 end Find_Comparison_Types;
5163 ----------------------------------------
5164 -- Find_Non_Universal_Interpretations --
5165 ----------------------------------------
5167 procedure Find_Non_Universal_Interpretations
5173 Index : Interp_Index;
5177 if T1 = Universal_Integer
5178 or else T1 = Universal_Real
5180 if not Is_Overloaded (R) then
5182 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
5184 Get_First_Interp (R, Index, It);
5185 while Present (It.Typ) loop
5186 if Covers (It.Typ, T1) then
5188 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
5191 Get_Next_Interp (Index, It);
5195 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
5197 end Find_Non_Universal_Interpretations;
5199 ------------------------------
5200 -- Find_Concatenation_Types --
5201 ------------------------------
5203 procedure Find_Concatenation_Types
5208 Op_Type : constant Entity_Id := Etype (Op_Id);
5211 if Is_Array_Type (Op_Type)
5212 and then not Is_Limited_Type (Op_Type)
5214 and then (Has_Compatible_Type (L, Op_Type)
5216 Has_Compatible_Type (L, Component_Type (Op_Type)))
5218 and then (Has_Compatible_Type (R, Op_Type)
5220 Has_Compatible_Type (R, Component_Type (Op_Type)))
5222 Add_One_Interp (N, Op_Id, Op_Type);
5224 end Find_Concatenation_Types;
5226 -------------------------
5227 -- Find_Equality_Types --
5228 -------------------------
5230 procedure Find_Equality_Types
5235 Index : Interp_Index;
5237 Found : Boolean := False;
5240 Scop : Entity_Id := Empty;
5242 procedure Try_One_Interp (T1 : Entity_Id);
5243 -- The context of the equality operator plays no role in resolving the
5244 -- arguments, so that if there is more than one interpretation of the
5245 -- operands that is compatible with equality, the construct is ambiguous
5246 -- and an error can be emitted now, after trying to disambiguate, i.e.
5247 -- applying preference rules.
5249 --------------------
5250 -- Try_One_Interp --
5251 --------------------
5253 procedure Try_One_Interp (T1 : Entity_Id) is
5254 Bas : constant Entity_Id := Base_Type (T1);
5257 -- If the operator is an expanded name, then the type of the operand
5258 -- must be defined in the corresponding scope. If the type is
5259 -- universal, the context will impose the correct type. An anonymous
5260 -- type for a 'Access reference is also universal in this sense, as
5261 -- the actual type is obtained from context.
5262 -- In Ada 2005, the equality operator for anonymous access types
5263 -- is declared in Standard, and preference rules apply to it.
5265 if Present (Scop) then
5266 if Defined_In_Scope (T1, Scop)
5267 or else T1 = Universal_Integer
5268 or else T1 = Universal_Real
5269 or else T1 = Any_Access
5270 or else T1 = Any_String
5271 or else T1 = Any_Composite
5272 or else (Ekind (T1) = E_Access_Subprogram_Type
5273 and then not Comes_From_Source (T1))
5277 elsif Ekind (T1) = E_Anonymous_Access_Type
5278 and then Scop = Standard_Standard
5283 -- The scope does not contain an operator for the type
5288 -- If we have infix notation, the operator must be usable.
5289 -- Within an instance, if the type is already established we
5290 -- know it is correct.
5291 -- In Ada 2005, the equality on anonymous access types is declared
5292 -- in Standard, and is always visible.
5294 elsif In_Open_Scopes (Scope (Bas))
5295 or else Is_Potentially_Use_Visible (Bas)
5296 or else In_Use (Bas)
5297 or else (In_Use (Scope (Bas))
5298 and then not Is_Hidden (Bas))
5299 or else (In_Instance
5300 and then First_Subtype (T1) = First_Subtype (Etype (R)))
5301 or else Ekind (T1) = E_Anonymous_Access_Type
5306 -- Save candidate type for subsquent error message, if any
5308 if not Is_Limited_Type (T1) then
5309 Candidate_Type := T1;
5315 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
5316 -- Do not allow anonymous access types in equality operators.
5318 if Ada_Version < Ada_2005
5319 and then Ekind (T1) = E_Anonymous_Access_Type
5324 if T1 /= Standard_Void_Type
5325 and then not Is_Limited_Type (T1)
5326 and then not Is_Limited_Composite (T1)
5327 and then Has_Compatible_Type (R, T1)
5330 and then Base_Type (T1) /= Base_Type (T_F)
5332 It := Disambiguate (L, I_F, Index, Any_Type);
5334 if It = No_Interp then
5335 Ambiguous_Operands (N);
5336 Set_Etype (L, Any_Type);
5349 if not Analyzed (L) then
5353 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5355 -- Case of operator was not visible, Etype still set to Any_Type
5357 if Etype (N) = Any_Type then
5361 elsif Scop = Standard_Standard
5362 and then Ekind (T1) = E_Anonymous_Access_Type
5368 -- Start of processing for Find_Equality_Types
5371 -- If left operand is aggregate, the right operand has to
5372 -- provide a usable type for it.
5374 if Nkind (L) = N_Aggregate
5375 and then Nkind (R) /= N_Aggregate
5377 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5381 if Nkind (N) = N_Function_Call
5382 and then Nkind (Name (N)) = N_Expanded_Name
5384 Scop := Entity (Prefix (Name (N)));
5386 -- The prefix may be a package renaming, and the subsequent test
5387 -- requires the original package.
5389 if Ekind (Scop) = E_Package
5390 and then Present (Renamed_Entity (Scop))
5392 Scop := Renamed_Entity (Scop);
5393 Set_Entity (Prefix (Name (N)), Scop);
5397 if not Is_Overloaded (L) then
5398 Try_One_Interp (Etype (L));
5401 Get_First_Interp (L, Index, It);
5402 while Present (It.Typ) loop
5403 Try_One_Interp (It.Typ);
5404 Get_Next_Interp (Index, It);
5407 end Find_Equality_Types;
5409 -------------------------
5410 -- Find_Negation_Types --
5411 -------------------------
5413 procedure Find_Negation_Types
5418 Index : Interp_Index;
5422 if not Is_Overloaded (R) then
5423 if Etype (R) = Universal_Integer then
5424 Add_One_Interp (N, Op_Id, Any_Modular);
5425 elsif Valid_Boolean_Arg (Etype (R)) then
5426 Add_One_Interp (N, Op_Id, Etype (R));
5430 Get_First_Interp (R, Index, It);
5431 while Present (It.Typ) loop
5432 if Valid_Boolean_Arg (It.Typ) then
5433 Add_One_Interp (N, Op_Id, It.Typ);
5436 Get_Next_Interp (Index, It);
5439 end Find_Negation_Types;
5441 ------------------------------
5442 -- Find_Primitive_Operation --
5443 ------------------------------
5445 function Find_Primitive_Operation (N : Node_Id) return Boolean is
5446 Obj : constant Node_Id := Prefix (N);
5447 Op : constant Node_Id := Selector_Name (N);
5454 Set_Etype (Op, Any_Type);
5456 if Is_Access_Type (Etype (Obj)) then
5457 Typ := Designated_Type (Etype (Obj));
5462 if Is_Class_Wide_Type (Typ) then
5463 Typ := Root_Type (Typ);
5466 Prims := Primitive_Operations (Typ);
5468 Prim := First_Elmt (Prims);
5469 while Present (Prim) loop
5470 if Chars (Node (Prim)) = Chars (Op) then
5471 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
5472 Set_Etype (N, Etype (Node (Prim)));
5478 -- Now look for class-wide operations of the type or any of its
5479 -- ancestors by iterating over the homonyms of the selector.
5482 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
5486 Hom := Current_Entity (Op);
5487 while Present (Hom) loop
5488 if (Ekind (Hom) = E_Procedure
5490 Ekind (Hom) = E_Function)
5491 and then Scope (Hom) = Scope (Typ)
5492 and then Present (First_Formal (Hom))
5494 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
5496 (Is_Access_Type (Etype (First_Formal (Hom)))
5498 Ekind (Etype (First_Formal (Hom))) =
5499 E_Anonymous_Access_Type
5502 (Designated_Type (Etype (First_Formal (Hom)))) =
5505 Add_One_Interp (Op, Hom, Etype (Hom));
5506 Set_Etype (N, Etype (Hom));
5509 Hom := Homonym (Hom);
5513 return Etype (Op) /= Any_Type;
5514 end Find_Primitive_Operation;
5516 ----------------------
5517 -- Find_Unary_Types --
5518 ----------------------
5520 procedure Find_Unary_Types
5525 Index : Interp_Index;
5529 if not Is_Overloaded (R) then
5530 if Is_Numeric_Type (Etype (R)) then
5531 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
5535 Get_First_Interp (R, Index, It);
5536 while Present (It.Typ) loop
5537 if Is_Numeric_Type (It.Typ) then
5538 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
5541 Get_Next_Interp (Index, It);
5544 end Find_Unary_Types;
5550 function Junk_Operand (N : Node_Id) return Boolean is
5554 if Error_Posted (N) then
5558 -- Get entity to be tested
5560 if Is_Entity_Name (N)
5561 and then Present (Entity (N))
5565 -- An odd case, a procedure name gets converted to a very peculiar
5566 -- function call, and here is where we detect this happening.
5568 elsif Nkind (N) = N_Function_Call
5569 and then Is_Entity_Name (Name (N))
5570 and then Present (Entity (Name (N)))
5574 -- Another odd case, there are at least some cases of selected
5575 -- components where the selected component is not marked as having
5576 -- an entity, even though the selector does have an entity
5578 elsif Nkind (N) = N_Selected_Component
5579 and then Present (Entity (Selector_Name (N)))
5581 Enode := Selector_Name (N);
5587 -- Now test the entity we got to see if it is a bad case
5589 case Ekind (Entity (Enode)) is
5593 ("package name cannot be used as operand", Enode);
5595 when Generic_Unit_Kind =>
5597 ("generic unit name cannot be used as operand", Enode);
5601 ("subtype name cannot be used as operand", Enode);
5605 ("entry name cannot be used as operand", Enode);
5609 ("procedure name cannot be used as operand", Enode);
5613 ("exception name cannot be used as operand", Enode);
5615 when E_Block | E_Label | E_Loop =>
5617 ("label name cannot be used as operand", Enode);
5627 --------------------
5628 -- Operator_Check --
5629 --------------------
5631 procedure Operator_Check (N : Node_Id) is
5633 Remove_Abstract_Operations (N);
5635 -- Test for case of no interpretation found for operator
5637 if Etype (N) = Any_Type then
5641 Op_Id : Entity_Id := Empty;
5644 R := Right_Opnd (N);
5646 if Nkind (N) in N_Binary_Op then
5652 -- If either operand has no type, then don't complain further,
5653 -- since this simply means that we have a propagated error.
5656 or else Etype (R) = Any_Type
5657 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5661 -- We explicitly check for the case of concatenation of component
5662 -- with component to avoid reporting spurious matching array types
5663 -- that might happen to be lurking in distant packages (such as
5664 -- run-time packages). This also prevents inconsistencies in the
5665 -- messages for certain ACVC B tests, which can vary depending on
5666 -- types declared in run-time interfaces. Another improvement when
5667 -- aggregates are present is to look for a well-typed operand.
5669 elsif Present (Candidate_Type)
5670 and then (Nkind (N) /= N_Op_Concat
5671 or else Is_Array_Type (Etype (L))
5672 or else Is_Array_Type (Etype (R)))
5674 if Nkind (N) = N_Op_Concat then
5675 if Etype (L) /= Any_Composite
5676 and then Is_Array_Type (Etype (L))
5678 Candidate_Type := Etype (L);
5680 elsif Etype (R) /= Any_Composite
5681 and then Is_Array_Type (Etype (R))
5683 Candidate_Type := Etype (R);
5687 Error_Msg_NE -- CODEFIX
5688 ("operator for} is not directly visible!",
5689 N, First_Subtype (Candidate_Type));
5690 Error_Msg_N -- CODEFIX
5691 ("use clause would make operation legal!", N);
5694 -- If either operand is a junk operand (e.g. package name), then
5695 -- post appropriate error messages, but do not complain further.
5697 -- Note that the use of OR in this test instead of OR ELSE is
5698 -- quite deliberate, we may as well check both operands in the
5699 -- binary operator case.
5701 elsif Junk_Operand (R)
5702 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5706 -- If we have a logical operator, one of whose operands is
5707 -- Boolean, then we know that the other operand cannot resolve to
5708 -- Boolean (since we got no interpretations), but in that case we
5709 -- pretty much know that the other operand should be Boolean, so
5710 -- resolve it that way (generating an error)
5712 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5713 if Etype (L) = Standard_Boolean then
5714 Resolve (R, Standard_Boolean);
5716 elsif Etype (R) = Standard_Boolean then
5717 Resolve (L, Standard_Boolean);
5721 -- For an arithmetic operator or comparison operator, if one
5722 -- of the operands is numeric, then we know the other operand
5723 -- is not the same numeric type. If it is a non-numeric type,
5724 -- then probably it is intended to match the other operand.
5726 elsif Nkind_In (N, N_Op_Add,
5732 Nkind_In (N, N_Op_Lt,
5738 if Is_Numeric_Type (Etype (L))
5739 and then not Is_Numeric_Type (Etype (R))
5741 Resolve (R, Etype (L));
5744 elsif Is_Numeric_Type (Etype (R))
5745 and then not Is_Numeric_Type (Etype (L))
5747 Resolve (L, Etype (R));
5751 -- Comparisons on A'Access are common enough to deserve a
5754 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5755 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5756 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5759 ("two access attributes cannot be compared directly", N);
5761 ("\use qualified expression for one of the operands",
5765 -- Another one for C programmers
5767 elsif Nkind (N) = N_Op_Concat
5768 and then Valid_Boolean_Arg (Etype (L))
5769 and then Valid_Boolean_Arg (Etype (R))
5771 Error_Msg_N ("invalid operands for concatenation", N);
5772 Error_Msg_N -- CODEFIX
5773 ("\maybe AND was meant", N);
5776 -- A special case for comparison of access parameter with null
5778 elsif Nkind (N) = N_Op_Eq
5779 and then Is_Entity_Name (L)
5780 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5781 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5783 and then Nkind (R) = N_Null
5785 Error_Msg_N ("access parameter is not allowed to be null", L);
5786 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5789 -- Another special case for exponentiation, where the right
5790 -- operand must be Natural, independently of the base.
5792 elsif Nkind (N) = N_Op_Expon
5793 and then Is_Numeric_Type (Etype (L))
5794 and then not Is_Overloaded (R)
5796 First_Subtype (Base_Type (Etype (R))) /= Standard_Integer
5797 and then Base_Type (Etype (R)) /= Universal_Integer
5800 ("exponent must be of type Natural, found}", R, Etype (R));
5804 -- If we fall through then just give general message. Note that in
5805 -- the following messages, if the operand is overloaded we choose
5806 -- an arbitrary type to complain about, but that is probably more
5807 -- useful than not giving a type at all.
5809 if Nkind (N) in N_Unary_Op then
5810 Error_Msg_Node_2 := Etype (R);
5811 Error_Msg_N ("operator& not defined for}", N);
5815 if Nkind (N) in N_Binary_Op then
5816 if not Is_Overloaded (L)
5817 and then not Is_Overloaded (R)
5818 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5820 Error_Msg_Node_2 := First_Subtype (Etype (R));
5821 Error_Msg_N ("there is no applicable operator& for}", N);
5824 -- Another attempt to find a fix: one of the candidate
5825 -- interpretations may not be use-visible. This has
5826 -- already been checked for predefined operators, so
5827 -- we examine only user-defined functions.
5829 Op_Id := Get_Name_Entity_Id (Chars (N));
5831 while Present (Op_Id) loop
5832 if Ekind (Op_Id) /= E_Operator
5833 and then Is_Overloadable (Op_Id)
5835 if not Is_Immediately_Visible (Op_Id)
5836 and then not In_Use (Scope (Op_Id))
5837 and then not Is_Abstract_Subprogram (Op_Id)
5838 and then not Is_Hidden (Op_Id)
5839 and then Ekind (Scope (Op_Id)) = E_Package
5842 (L, Etype (First_Formal (Op_Id)))
5844 (Next_Formal (First_Formal (Op_Id)))
5848 Etype (Next_Formal (First_Formal (Op_Id))))
5851 ("No legal interpretation for operator&", N);
5853 ("\use clause on& would make operation legal",
5859 Op_Id := Homonym (Op_Id);
5863 Error_Msg_N ("invalid operand types for operator&", N);
5865 if Nkind (N) /= N_Op_Concat then
5866 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5867 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5877 -----------------------------------------
5878 -- Process_Implicit_Dereference_Prefix --
5879 -----------------------------------------
5881 function Process_Implicit_Dereference_Prefix
5883 P : Entity_Id) return Entity_Id
5886 Typ : constant Entity_Id := Designated_Type (Etype (P));
5890 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5892 -- We create a dummy reference to E to ensure that the reference
5893 -- is not considered as part of an assignment (an implicit
5894 -- dereference can never assign to its prefix). The Comes_From_Source
5895 -- attribute needs to be propagated for accurate warnings.
5897 Ref := New_Reference_To (E, Sloc (P));
5898 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5899 Generate_Reference (E, Ref);
5902 -- An implicit dereference is a legal occurrence of an
5903 -- incomplete type imported through a limited_with clause,
5904 -- if the full view is visible.
5906 if From_With_Type (Typ)
5907 and then not From_With_Type (Scope (Typ))
5909 (Is_Immediately_Visible (Scope (Typ))
5911 (Is_Child_Unit (Scope (Typ))
5912 and then Is_Visible_Child_Unit (Scope (Typ))))
5914 return Available_View (Typ);
5919 end Process_Implicit_Dereference_Prefix;
5921 --------------------------------
5922 -- Remove_Abstract_Operations --
5923 --------------------------------
5925 procedure Remove_Abstract_Operations (N : Node_Id) is
5926 Abstract_Op : Entity_Id := Empty;
5927 Address_Kludge : Boolean := False;
5931 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5932 -- activate this if either extensions are enabled, or if the abstract
5933 -- operation in question comes from a predefined file. This latter test
5934 -- allows us to use abstract to make operations invisible to users. In
5935 -- particular, if type Address is non-private and abstract subprograms
5936 -- are used to hide its operators, they will be truly hidden.
5938 type Operand_Position is (First_Op, Second_Op);
5939 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5941 procedure Remove_Address_Interpretations (Op : Operand_Position);
5942 -- Ambiguities may arise when the operands are literal and the address
5943 -- operations in s-auxdec are visible. In that case, remove the
5944 -- interpretation of a literal as Address, to retain the semantics of
5945 -- Address as a private type.
5947 ------------------------------------
5948 -- Remove_Address_Interpretations --
5949 ------------------------------------
5951 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5955 if Is_Overloaded (N) then
5956 Get_First_Interp (N, I, It);
5957 while Present (It.Nam) loop
5958 Formal := First_Entity (It.Nam);
5960 if Op = Second_Op then
5961 Formal := Next_Entity (Formal);
5964 if Is_Descendent_Of_Address (Etype (Formal)) then
5965 Address_Kludge := True;
5969 Get_Next_Interp (I, It);
5972 end Remove_Address_Interpretations;
5974 -- Start of processing for Remove_Abstract_Operations
5977 if Is_Overloaded (N) then
5978 Get_First_Interp (N, I, It);
5980 while Present (It.Nam) loop
5981 if Is_Overloadable (It.Nam)
5982 and then Is_Abstract_Subprogram (It.Nam)
5983 and then not Is_Dispatching_Operation (It.Nam)
5985 Abstract_Op := It.Nam;
5987 if Is_Descendent_Of_Address (It.Typ) then
5988 Address_Kludge := True;
5992 -- In Ada 2005, this operation does not participate in Overload
5993 -- resolution. If the operation is defined in a predefined
5994 -- unit, it is one of the operations declared abstract in some
5995 -- variants of System, and it must be removed as well.
5997 elsif Ada_Version >= Ada_2005
5998 or else Is_Predefined_File_Name
5999 (Unit_File_Name (Get_Source_Unit (It.Nam)))
6006 Get_Next_Interp (I, It);
6009 if No (Abstract_Op) then
6011 -- If some interpretation yields an integer type, it is still
6012 -- possible that there are address interpretations. Remove them
6013 -- if one operand is a literal, to avoid spurious ambiguities
6014 -- on systems where Address is a visible integer type.
6016 if Is_Overloaded (N)
6017 and then Nkind (N) in N_Op
6018 and then Is_Integer_Type (Etype (N))
6020 if Nkind (N) in N_Binary_Op then
6021 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
6022 Remove_Address_Interpretations (Second_Op);
6024 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
6025 Remove_Address_Interpretations (First_Op);
6030 elsif Nkind (N) in N_Op then
6032 -- Remove interpretations that treat literals as addresses. This
6033 -- is never appropriate, even when Address is defined as a visible
6034 -- Integer type. The reason is that we would really prefer Address
6035 -- to behave as a private type, even in this case, which is there
6036 -- only to accommodate oddities of VMS address sizes. If Address
6037 -- is a visible integer type, we get lots of overload ambiguities.
6039 if Nkind (N) in N_Binary_Op then
6041 U1 : constant Boolean :=
6042 Present (Universal_Interpretation (Right_Opnd (N)));
6043 U2 : constant Boolean :=
6044 Present (Universal_Interpretation (Left_Opnd (N)));
6048 Remove_Address_Interpretations (Second_Op);
6052 Remove_Address_Interpretations (First_Op);
6055 if not (U1 and U2) then
6057 -- Remove corresponding predefined operator, which is
6058 -- always added to the overload set.
6060 Get_First_Interp (N, I, It);
6061 while Present (It.Nam) loop
6062 if Scope (It.Nam) = Standard_Standard
6063 and then Base_Type (It.Typ) =
6064 Base_Type (Etype (Abstract_Op))
6069 Get_Next_Interp (I, It);
6072 elsif Is_Overloaded (N)
6073 and then Present (Univ_Type)
6075 -- If both operands have a universal interpretation,
6076 -- it is still necessary to remove interpretations that
6077 -- yield Address. Any remaining ambiguities will be
6078 -- removed in Disambiguate.
6080 Get_First_Interp (N, I, It);
6081 while Present (It.Nam) loop
6082 if Is_Descendent_Of_Address (It.Typ) then
6085 elsif not Is_Type (It.Nam) then
6086 Set_Entity (N, It.Nam);
6089 Get_Next_Interp (I, It);
6095 elsif Nkind (N) = N_Function_Call
6097 (Nkind (Name (N)) = N_Operator_Symbol
6099 (Nkind (Name (N)) = N_Expanded_Name
6101 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
6105 Arg1 : constant Node_Id := First (Parameter_Associations (N));
6106 U1 : constant Boolean :=
6107 Present (Universal_Interpretation (Arg1));
6108 U2 : constant Boolean :=
6109 Present (Next (Arg1)) and then
6110 Present (Universal_Interpretation (Next (Arg1)));
6114 Remove_Address_Interpretations (First_Op);
6118 Remove_Address_Interpretations (Second_Op);
6121 if not (U1 and U2) then
6122 Get_First_Interp (N, I, It);
6123 while Present (It.Nam) loop
6124 if Scope (It.Nam) = Standard_Standard
6125 and then It.Typ = Base_Type (Etype (Abstract_Op))
6130 Get_Next_Interp (I, It);
6136 -- If the removal has left no valid interpretations, emit an error
6137 -- message now and label node as illegal.
6139 if Present (Abstract_Op) then
6140 Get_First_Interp (N, I, It);
6144 -- Removal of abstract operation left no viable candidate
6146 Set_Etype (N, Any_Type);
6147 Error_Msg_Sloc := Sloc (Abstract_Op);
6149 ("cannot call abstract operation& declared#", N, Abstract_Op);
6151 -- In Ada 2005, an abstract operation may disable predefined
6152 -- operators. Since the context is not yet known, we mark the
6153 -- predefined operators as potentially hidden. Do not include
6154 -- predefined operators when addresses are involved since this
6155 -- case is handled separately.
6157 elsif Ada_Version >= Ada_2005
6158 and then not Address_Kludge
6160 while Present (It.Nam) loop
6161 if Is_Numeric_Type (It.Typ)
6162 and then Scope (It.Typ) = Standard_Standard
6164 Set_Abstract_Op (I, Abstract_Op);
6167 Get_Next_Interp (I, It);
6172 end Remove_Abstract_Operations;
6174 -----------------------
6175 -- Try_Indirect_Call --
6176 -----------------------
6178 function Try_Indirect_Call
6181 Typ : Entity_Id) return Boolean
6187 pragma Warnings (Off, Call_OK);
6190 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
6192 Actual := First_Actual (N);
6193 Formal := First_Formal (Designated_Type (Typ));
6194 while Present (Actual) and then Present (Formal) loop
6195 if not Has_Compatible_Type (Actual, Etype (Formal)) then
6200 Next_Formal (Formal);
6203 if No (Actual) and then No (Formal) then
6204 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
6206 -- Nam is a candidate interpretation for the name in the call,
6207 -- if it is not an indirect call.
6209 if not Is_Type (Nam)
6210 and then Is_Entity_Name (Name (N))
6212 Set_Entity (Name (N), Nam);
6219 end Try_Indirect_Call;
6221 ----------------------
6222 -- Try_Indexed_Call --
6223 ----------------------
6225 function Try_Indexed_Call
6229 Skip_First : Boolean) return Boolean
6231 Loc : constant Source_Ptr := Sloc (N);
6232 Actuals : constant List_Id := Parameter_Associations (N);
6237 Actual := First (Actuals);
6239 -- If the call was originally written in prefix form, skip the first
6240 -- actual, which is obviously not defaulted.
6246 Index := First_Index (Typ);
6247 while Present (Actual) and then Present (Index) loop
6249 -- If the parameter list has a named association, the expression
6250 -- is definitely a call and not an indexed component.
6252 if Nkind (Actual) = N_Parameter_Association then
6256 if Is_Entity_Name (Actual)
6257 and then Is_Type (Entity (Actual))
6258 and then No (Next (Actual))
6260 -- A single actual that is a type name indicates a slice if the
6261 -- type is discrete, and an error otherwise.
6263 if Is_Discrete_Type (Entity (Actual)) then
6267 Make_Function_Call (Loc,
6268 Name => Relocate_Node (Name (N))),
6270 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
6275 Error_Msg_N ("invalid use of type in expression", Actual);
6276 Set_Etype (N, Any_Type);
6281 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
6289 if No (Actual) and then No (Index) then
6290 Add_One_Interp (N, Nam, Component_Type (Typ));
6292 -- Nam is a candidate interpretation for the name in the call,
6293 -- if it is not an indirect call.
6295 if not Is_Type (Nam)
6296 and then Is_Entity_Name (Name (N))
6298 Set_Entity (Name (N), Nam);
6305 end Try_Indexed_Call;
6307 --------------------------
6308 -- Try_Object_Operation --
6309 --------------------------
6311 function Try_Object_Operation (N : Node_Id) return Boolean is
6312 K : constant Node_Kind := Nkind (Parent (N));
6313 Is_Subprg_Call : constant Boolean := Nkind_In
6314 (K, N_Procedure_Call_Statement,
6316 Loc : constant Source_Ptr := Sloc (N);
6317 Obj : constant Node_Id := Prefix (N);
6319 Subprog : constant Node_Id :=
6320 Make_Identifier (Sloc (Selector_Name (N)),
6321 Chars => Chars (Selector_Name (N)));
6322 -- Identifier on which possible interpretations will be collected
6324 Report_Error : Boolean := False;
6325 -- If no candidate interpretation matches the context, redo the
6326 -- analysis with error enabled to provide additional information.
6329 Candidate : Entity_Id := Empty;
6330 New_Call_Node : Node_Id := Empty;
6331 Node_To_Replace : Node_Id;
6332 Obj_Type : Entity_Id := Etype (Obj);
6333 Success : Boolean := False;
6335 function Valid_Candidate
6338 Subp : Entity_Id) return Entity_Id;
6339 -- If the subprogram is a valid interpretation, record it, and add
6340 -- to the list of interpretations of Subprog.
6342 procedure Complete_Object_Operation
6343 (Call_Node : Node_Id;
6344 Node_To_Replace : Node_Id);
6345 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
6346 -- Call_Node, insert the object (or its dereference) as the first actual
6347 -- in the call, and complete the analysis of the call.
6349 procedure Report_Ambiguity (Op : Entity_Id);
6350 -- If a prefixed procedure call is ambiguous, indicate whether the
6351 -- call includes an implicit dereference or an implicit 'Access.
6353 procedure Transform_Object_Operation
6354 (Call_Node : out Node_Id;
6355 Node_To_Replace : out Node_Id);
6356 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
6357 -- Call_Node is the resulting subprogram call, Node_To_Replace is
6358 -- either N or the parent of N, and Subprog is a reference to the
6359 -- subprogram we are trying to match.
6361 function Try_Class_Wide_Operation
6362 (Call_Node : Node_Id;
6363 Node_To_Replace : Node_Id) return Boolean;
6364 -- Traverse all ancestor types looking for a class-wide subprogram
6365 -- for which the current operation is a valid non-dispatching call.
6367 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
6368 -- If prefix is overloaded, its interpretation may include different
6369 -- tagged types, and we must examine the primitive operations and
6370 -- the class-wide operations of each in order to find candidate
6371 -- interpretations for the call as a whole.
6373 function Try_Primitive_Operation
6374 (Call_Node : Node_Id;
6375 Node_To_Replace : Node_Id) return Boolean;
6376 -- Traverse the list of primitive subprograms looking for a dispatching
6377 -- operation for which the current node is a valid call .
6379 ---------------------
6380 -- Valid_Candidate --
6381 ---------------------
6383 function Valid_Candidate
6386 Subp : Entity_Id) return Entity_Id
6388 Arr_Type : Entity_Id;
6389 Comp_Type : Entity_Id;
6392 -- If the subprogram is a valid interpretation, record it in global
6393 -- variable Subprog, to collect all possible overloadings.
6396 if Subp /= Entity (Subprog) then
6397 Add_One_Interp (Subprog, Subp, Etype (Subp));
6401 -- If the call may be an indexed call, retrieve component type of
6402 -- resulting expression, and add possible interpretation.
6407 if Nkind (Call) = N_Function_Call
6408 and then Nkind (Parent (N)) = N_Indexed_Component
6409 and then Needs_One_Actual (Subp)
6411 if Is_Array_Type (Etype (Subp)) then
6412 Arr_Type := Etype (Subp);
6414 elsif Is_Access_Type (Etype (Subp))
6415 and then Is_Array_Type (Designated_Type (Etype (Subp)))
6417 Arr_Type := Designated_Type (Etype (Subp));
6421 if Present (Arr_Type) then
6423 -- Verify that the actuals (excluding the object) match the types
6431 Actual := Next (First_Actual (Call));
6432 Index := First_Index (Arr_Type);
6433 while Present (Actual) and then Present (Index) loop
6434 if not Has_Compatible_Type (Actual, Etype (Index)) then
6439 Next_Actual (Actual);
6445 and then Present (Arr_Type)
6447 Comp_Type := Component_Type (Arr_Type);
6451 if Present (Comp_Type)
6452 and then Etype (Subprog) /= Comp_Type
6454 Add_One_Interp (Subprog, Subp, Comp_Type);
6458 if Etype (Call) /= Any_Type then
6463 end Valid_Candidate;
6465 -------------------------------
6466 -- Complete_Object_Operation --
6467 -------------------------------
6469 procedure Complete_Object_Operation
6470 (Call_Node : Node_Id;
6471 Node_To_Replace : Node_Id)
6473 Control : constant Entity_Id := First_Formal (Entity (Subprog));
6474 Formal_Type : constant Entity_Id := Etype (Control);
6475 First_Actual : Node_Id;
6478 -- Place the name of the operation, with its interpretations,
6479 -- on the rewritten call.
6481 Set_Name (Call_Node, Subprog);
6483 First_Actual := First (Parameter_Associations (Call_Node));
6485 -- For cross-reference purposes, treat the new node as being in
6486 -- the source if the original one is.
6488 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
6489 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
6491 if Nkind (N) = N_Selected_Component
6492 and then not Inside_A_Generic
6494 Set_Entity (Selector_Name (N), Entity (Subprog));
6497 -- If need be, rewrite first actual as an explicit dereference
6498 -- If the call is overloaded, the rewriting can only be done
6499 -- once the primitive operation is identified.
6501 if Is_Overloaded (Subprog) then
6503 -- The prefix itself may be overloaded, and its interpretations
6504 -- must be propagated to the new actual in the call.
6506 if Is_Overloaded (Obj) then
6507 Save_Interps (Obj, First_Actual);
6510 Rewrite (First_Actual, Obj);
6512 elsif not Is_Access_Type (Formal_Type)
6513 and then Is_Access_Type (Etype (Obj))
6515 Rewrite (First_Actual,
6516 Make_Explicit_Dereference (Sloc (Obj), Obj));
6517 Analyze (First_Actual);
6519 -- If we need to introduce an explicit dereference, verify that
6520 -- the resulting actual is compatible with the mode of the formal.
6522 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
6523 and then Is_Access_Constant (Etype (Obj))
6526 ("expect variable in call to&", Prefix (N), Entity (Subprog));
6529 -- Conversely, if the formal is an access parameter and the object
6530 -- is not, replace the actual with a 'Access reference. Its analysis
6531 -- will check that the object is aliased.
6533 elsif Is_Access_Type (Formal_Type)
6534 and then not Is_Access_Type (Etype (Obj))
6536 -- A special case: A.all'access is illegal if A is an access to a
6537 -- constant and the context requires an access to a variable.
6539 if not Is_Access_Constant (Formal_Type) then
6540 if (Nkind (Obj) = N_Explicit_Dereference
6541 and then Is_Access_Constant (Etype (Prefix (Obj))))
6542 or else not Is_Variable (Obj)
6545 ("actual for& must be a variable", Obj, Control);
6549 Rewrite (First_Actual,
6550 Make_Attribute_Reference (Loc,
6551 Attribute_Name => Name_Access,
6552 Prefix => Relocate_Node (Obj)));
6554 if not Is_Aliased_View (Obj) then
6556 ("object in prefixed call to& must be aliased"
6557 & " (RM-2005 4.3.1 (13))",
6558 Prefix (First_Actual), Subprog);
6561 Analyze (First_Actual);
6564 if Is_Overloaded (Obj) then
6565 Save_Interps (Obj, First_Actual);
6568 Rewrite (First_Actual, Obj);
6571 Rewrite (Node_To_Replace, Call_Node);
6573 -- Propagate the interpretations collected in subprog to the new
6574 -- function call node, to be resolved from context.
6576 if Is_Overloaded (Subprog) then
6577 Save_Interps (Subprog, Node_To_Replace);
6580 Analyze (Node_To_Replace);
6582 -- If the operation has been rewritten into a call, which may get
6583 -- subsequently an explicit dereference, preserve the type on the
6584 -- original node (selected component or indexed component) for
6585 -- subsequent legality tests, e.g. Is_Variable. which examines
6586 -- the original node.
6588 if Nkind (Node_To_Replace) = N_Function_Call then
6590 (Original_Node (Node_To_Replace), Etype (Node_To_Replace));
6593 end Complete_Object_Operation;
6595 ----------------------
6596 -- Report_Ambiguity --
6597 ----------------------
6599 procedure Report_Ambiguity (Op : Entity_Id) is
6600 Access_Formal : constant Boolean :=
6601 Is_Access_Type (Etype (First_Formal (Op)));
6602 Access_Actual : constant Boolean :=
6603 Is_Access_Type (Etype (Prefix (N)));
6606 Error_Msg_Sloc := Sloc (Op);
6608 if Access_Formal and then not Access_Actual then
6609 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6611 ("\possible interpretation"
6612 & " (inherited, with implicit 'Access) #", N);
6615 ("\possible interpretation (with implicit 'Access) #", N);
6618 elsif not Access_Formal and then Access_Actual then
6619 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6621 ("\possible interpretation"
6622 & " ( inherited, with implicit dereference) #", N);
6625 ("\possible interpretation (with implicit dereference) #", N);
6629 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6630 Error_Msg_N ("\possible interpretation (inherited)#", N);
6632 Error_Msg_N -- CODEFIX
6633 ("\possible interpretation#", N);
6636 end Report_Ambiguity;
6638 --------------------------------
6639 -- Transform_Object_Operation --
6640 --------------------------------
6642 procedure Transform_Object_Operation
6643 (Call_Node : out Node_Id;
6644 Node_To_Replace : out Node_Id)
6646 Dummy : constant Node_Id := New_Copy (Obj);
6647 -- Placeholder used as a first parameter in the call, replaced
6648 -- eventually by the proper object.
6650 Parent_Node : constant Node_Id := Parent (N);
6656 -- Common case covering 1) Call to a procedure and 2) Call to a
6657 -- function that has some additional actuals.
6659 if Nkind_In (Parent_Node, N_Function_Call,
6660 N_Procedure_Call_Statement)
6662 -- N is a selected component node containing the name of the
6663 -- subprogram. If N is not the name of the parent node we must
6664 -- not replace the parent node by the new construct. This case
6665 -- occurs when N is a parameterless call to a subprogram that
6666 -- is an actual parameter of a call to another subprogram. For
6668 -- Some_Subprogram (..., Obj.Operation, ...)
6670 and then Name (Parent_Node) = N
6672 Node_To_Replace := Parent_Node;
6674 Actuals := Parameter_Associations (Parent_Node);
6676 if Present (Actuals) then
6677 Prepend (Dummy, Actuals);
6679 Actuals := New_List (Dummy);
6682 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6684 Make_Procedure_Call_Statement (Loc,
6685 Name => New_Copy (Subprog),
6686 Parameter_Associations => Actuals);
6690 Make_Function_Call (Loc,
6691 Name => New_Copy (Subprog),
6692 Parameter_Associations => Actuals);
6696 -- Before analysis, a function call appears as an indexed component
6697 -- if there are no named associations.
6699 elsif Nkind (Parent_Node) = N_Indexed_Component
6700 and then N = Prefix (Parent_Node)
6702 Node_To_Replace := Parent_Node;
6703 Actuals := Expressions (Parent_Node);
6705 Actual := First (Actuals);
6706 while Present (Actual) loop
6711 Prepend (Dummy, Actuals);
6714 Make_Function_Call (Loc,
6715 Name => New_Copy (Subprog),
6716 Parameter_Associations => Actuals);
6718 -- Parameterless call: Obj.F is rewritten as F (Obj)
6721 Node_To_Replace := N;
6724 Make_Function_Call (Loc,
6725 Name => New_Copy (Subprog),
6726 Parameter_Associations => New_List (Dummy));
6728 end Transform_Object_Operation;
6730 ------------------------------
6731 -- Try_Class_Wide_Operation --
6732 ------------------------------
6734 function Try_Class_Wide_Operation
6735 (Call_Node : Node_Id;
6736 Node_To_Replace : Node_Id) return Boolean
6738 Anc_Type : Entity_Id;
6739 Matching_Op : Entity_Id := Empty;
6742 procedure Traverse_Homonyms
6743 (Anc_Type : Entity_Id;
6744 Error : out Boolean);
6745 -- Traverse the homonym chain of the subprogram searching for those
6746 -- homonyms whose first formal has the Anc_Type's class-wide type,
6747 -- or an anonymous access type designating the class-wide type. If
6748 -- an ambiguity is detected, then Error is set to True.
6750 procedure Traverse_Interfaces
6751 (Anc_Type : Entity_Id;
6752 Error : out Boolean);
6753 -- Traverse the list of interfaces, if any, associated with Anc_Type
6754 -- and search for acceptable class-wide homonyms associated with each
6755 -- interface. If an ambiguity is detected, then Error is set to True.
6757 -----------------------
6758 -- Traverse_Homonyms --
6759 -----------------------
6761 procedure Traverse_Homonyms
6762 (Anc_Type : Entity_Id;
6763 Error : out Boolean)
6765 Cls_Type : Entity_Id;
6773 Cls_Type := Class_Wide_Type (Anc_Type);
6775 Hom := Current_Entity (Subprog);
6777 -- Find operation whose first parameter is of the class-wide
6778 -- type, a subtype thereof, or an anonymous access to same.
6780 while Present (Hom) loop
6781 if (Ekind (Hom) = E_Procedure
6783 Ekind (Hom) = E_Function)
6784 and then Scope (Hom) = Scope (Anc_Type)
6785 and then Present (First_Formal (Hom))
6787 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6789 (Is_Access_Type (Etype (First_Formal (Hom)))
6791 Ekind (Etype (First_Formal (Hom))) =
6792 E_Anonymous_Access_Type
6795 (Designated_Type (Etype (First_Formal (Hom)))) =
6798 Set_Etype (Call_Node, Any_Type);
6799 Set_Is_Overloaded (Call_Node, False);
6802 if No (Matching_Op) then
6803 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6804 Set_Etype (Call_Node, Any_Type);
6805 Set_Parent (Call_Node, Parent (Node_To_Replace));
6807 Set_Name (Call_Node, Hom_Ref);
6812 Report => Report_Error,
6814 Skip_First => True);
6817 Valid_Candidate (Success, Call_Node, Hom);
6823 Report => Report_Error,
6825 Skip_First => True);
6827 if Present (Valid_Candidate (Success, Call_Node, Hom))
6828 and then Nkind (Call_Node) /= N_Function_Call
6830 Error_Msg_NE ("ambiguous call to&", N, Hom);
6831 Report_Ambiguity (Matching_Op);
6832 Report_Ambiguity (Hom);
6839 Hom := Homonym (Hom);
6841 end Traverse_Homonyms;
6843 -------------------------
6844 -- Traverse_Interfaces --
6845 -------------------------
6847 procedure Traverse_Interfaces
6848 (Anc_Type : Entity_Id;
6849 Error : out Boolean)
6851 Intface_List : constant List_Id :=
6852 Abstract_Interface_List (Anc_Type);
6858 if Is_Non_Empty_List (Intface_List) then
6859 Intface := First (Intface_List);
6860 while Present (Intface) loop
6862 -- Look for acceptable class-wide homonyms associated with
6865 Traverse_Homonyms (Etype (Intface), Error);
6871 -- Continue the search by looking at each of the interface's
6872 -- associated interface ancestors.
6874 Traverse_Interfaces (Etype (Intface), Error);
6883 end Traverse_Interfaces;
6885 -- Start of processing for Try_Class_Wide_Operation
6888 -- Loop through ancestor types (including interfaces), traversing
6889 -- the homonym chain of the subprogram, trying out those homonyms
6890 -- whose first formal has the class-wide type of the ancestor, or
6891 -- an anonymous access type designating the class-wide type.
6893 Anc_Type := Obj_Type;
6895 -- Look for a match among homonyms associated with the ancestor
6897 Traverse_Homonyms (Anc_Type, Error);
6903 -- Continue the search for matches among homonyms associated with
6904 -- any interfaces implemented by the ancestor.
6906 Traverse_Interfaces (Anc_Type, Error);
6912 exit when Etype (Anc_Type) = Anc_Type;
6913 Anc_Type := Etype (Anc_Type);
6916 if Present (Matching_Op) then
6917 Set_Etype (Call_Node, Etype (Matching_Op));
6920 return Present (Matching_Op);
6921 end Try_Class_Wide_Operation;
6923 -----------------------------------
6924 -- Try_One_Prefix_Interpretation --
6925 -----------------------------------
6927 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6931 if Is_Access_Type (Obj_Type) then
6932 Obj_Type := Designated_Type (Obj_Type);
6935 if Ekind (Obj_Type) = E_Private_Subtype then
6936 Obj_Type := Base_Type (Obj_Type);
6939 if Is_Class_Wide_Type (Obj_Type) then
6940 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6943 -- The type may have be obtained through a limited_with clause,
6944 -- in which case the primitive operations are available on its
6945 -- non-limited view. If still incomplete, retrieve full view.
6947 if Ekind (Obj_Type) = E_Incomplete_Type
6948 and then From_With_Type (Obj_Type)
6950 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6953 -- If the object is not tagged, or the type is still an incomplete
6954 -- type, this is not a prefixed call.
6956 if not Is_Tagged_Type (Obj_Type)
6957 or else Is_Incomplete_Type (Obj_Type)
6962 if Try_Primitive_Operation
6963 (Call_Node => New_Call_Node,
6964 Node_To_Replace => Node_To_Replace)
6966 Try_Class_Wide_Operation
6967 (Call_Node => New_Call_Node,
6968 Node_To_Replace => Node_To_Replace)
6972 end Try_One_Prefix_Interpretation;
6974 -----------------------------
6975 -- Try_Primitive_Operation --
6976 -----------------------------
6978 function Try_Primitive_Operation
6979 (Call_Node : Node_Id;
6980 Node_To_Replace : Node_Id) return Boolean
6983 Prim_Op : Entity_Id;
6984 Matching_Op : Entity_Id := Empty;
6985 Prim_Op_Ref : Node_Id := Empty;
6987 Corr_Type : Entity_Id := Empty;
6988 -- If the prefix is a synchronized type, the controlling type of
6989 -- the primitive operation is the corresponding record type, else
6990 -- this is the object type itself.
6992 Success : Boolean := False;
6994 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
6995 -- For tagged types the candidate interpretations are found in
6996 -- the list of primitive operations of the type and its ancestors.
6997 -- For formal tagged types we have to find the operations declared
6998 -- in the same scope as the type (including in the generic formal
6999 -- part) because the type itself carries no primitive operations,
7000 -- except for formal derived types that inherit the operations of
7001 -- the parent and progenitors.
7002 -- If the context is a generic subprogram body, the generic formals
7003 -- are visible by name, but are not in the entity list of the
7004 -- subprogram because that list starts with the subprogram formals.
7005 -- We retrieve the candidate operations from the generic declaration.
7007 function Is_Private_Overriding (Op : Entity_Id) return Boolean;
7008 -- An operation that overrides an inherited operation in the private
7009 -- part of its package may be hidden, but if the inherited operation
7010 -- is visible a direct call to it will dispatch to the private one,
7011 -- which is therefore a valid candidate.
7013 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
7014 -- Verify that the prefix, dereferenced if need be, is a valid
7015 -- controlling argument in a call to Op. The remaining actuals
7016 -- are checked in the subsequent call to Analyze_One_Call.
7018 ------------------------------
7019 -- Collect_Generic_Type_Ops --
7020 ------------------------------
7022 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
7023 Bas : constant Entity_Id := Base_Type (T);
7024 Candidates : constant Elist_Id := New_Elmt_List;
7028 procedure Check_Candidate;
7029 -- The operation is a candidate if its first parameter is a
7030 -- controlling operand of the desired type.
7032 -----------------------
7033 -- Check_Candidate; --
7034 -----------------------
7036 procedure Check_Candidate is
7038 Formal := First_Formal (Subp);
7041 and then Is_Controlling_Formal (Formal)
7043 (Base_Type (Etype (Formal)) = Bas
7045 (Is_Access_Type (Etype (Formal))
7046 and then Designated_Type (Etype (Formal)) = Bas))
7048 Append_Elmt (Subp, Candidates);
7050 end Check_Candidate;
7052 -- Start of processing for Collect_Generic_Type_Ops
7055 if Is_Derived_Type (T) then
7056 return Primitive_Operations (T);
7058 elsif Ekind_In (Scope (T), E_Procedure, E_Function) then
7060 -- Scan the list of generic formals to find subprograms
7061 -- that may have a first controlling formal of the type.
7063 if Nkind (Unit_Declaration_Node (Scope (T)))
7064 = N_Generic_Subprogram_Declaration
7071 First (Generic_Formal_Declarations
7072 (Unit_Declaration_Node (Scope (T))));
7073 while Present (Decl) loop
7074 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
7075 Subp := Defining_Entity (Decl);
7086 -- Scan the list of entities declared in the same scope as
7087 -- the type. In general this will be an open scope, given that
7088 -- the call we are analyzing can only appear within a generic
7089 -- declaration or body (either the one that declares T, or a
7092 -- For a subtype representing a generic actual type, go to the
7095 if Is_Generic_Actual_Type (T) then
7096 Subp := First_Entity (Scope (Base_Type (T)));
7098 Subp := First_Entity (Scope (T));
7101 while Present (Subp) loop
7102 if Is_Overloadable (Subp) then
7111 end Collect_Generic_Type_Ops;
7113 ---------------------------
7114 -- Is_Private_Overriding --
7115 ---------------------------
7117 function Is_Private_Overriding (Op : Entity_Id) return Boolean is
7118 Visible_Op : constant Entity_Id := Homonym (Op);
7121 return Present (Visible_Op)
7122 and then Scope (Op) = Scope (Visible_Op)
7123 and then not Comes_From_Source (Visible_Op)
7124 and then Alias (Visible_Op) = Op
7125 and then not Is_Hidden (Visible_Op);
7126 end Is_Private_Overriding;
7128 -----------------------------
7129 -- Valid_First_Argument_Of --
7130 -----------------------------
7132 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
7133 Typ : Entity_Id := Etype (First_Formal (Op));
7136 if Is_Concurrent_Type (Typ)
7137 and then Present (Corresponding_Record_Type (Typ))
7139 Typ := Corresponding_Record_Type (Typ);
7142 -- Simple case. Object may be a subtype of the tagged type or
7143 -- may be the corresponding record of a synchronized type.
7145 return Obj_Type = Typ
7146 or else Base_Type (Obj_Type) = Typ
7147 or else Corr_Type = Typ
7149 -- Prefix can be dereferenced
7152 (Is_Access_Type (Corr_Type)
7153 and then Designated_Type (Corr_Type) = Typ)
7155 -- Formal is an access parameter, for which the object
7156 -- can provide an access.
7159 (Ekind (Typ) = E_Anonymous_Access_Type
7160 and then Designated_Type (Typ) = Base_Type (Corr_Type));
7161 end Valid_First_Argument_Of;
7163 -- Start of processing for Try_Primitive_Operation
7166 -- Look for subprograms in the list of primitive operations. The name
7167 -- must be identical, and the kind of call indicates the expected
7168 -- kind of operation (function or procedure). If the type is a
7169 -- (tagged) synchronized type, the primitive ops are attached to the
7170 -- corresponding record (base) type.
7172 if Is_Concurrent_Type (Obj_Type) then
7173 if Present (Corresponding_Record_Type (Obj_Type)) then
7174 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
7175 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
7177 Corr_Type := Obj_Type;
7178 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7181 elsif not Is_Generic_Type (Obj_Type) then
7182 Corr_Type := Obj_Type;
7183 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
7186 Corr_Type := Obj_Type;
7187 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7190 while Present (Elmt) loop
7191 Prim_Op := Node (Elmt);
7193 if Chars (Prim_Op) = Chars (Subprog)
7194 and then Present (First_Formal (Prim_Op))
7195 and then Valid_First_Argument_Of (Prim_Op)
7197 (Nkind (Call_Node) = N_Function_Call)
7198 = (Ekind (Prim_Op) = E_Function)
7200 -- Ada 2005 (AI-251): If this primitive operation corresponds
7201 -- with an immediate ancestor interface there is no need to add
7202 -- it to the list of interpretations; the corresponding aliased
7203 -- primitive is also in this list of primitive operations and
7204 -- will be used instead.
7206 if (Present (Interface_Alias (Prim_Op))
7207 and then Is_Ancestor (Find_Dispatching_Type
7208 (Alias (Prim_Op)), Corr_Type))
7210 -- Do not consider hidden primitives unless the type is in an
7211 -- open scope or we are within an instance, where visibility
7212 -- is known to be correct, or else if this is an overriding
7213 -- operation in the private part for an inherited operation.
7215 or else (Is_Hidden (Prim_Op)
7216 and then not Is_Immediately_Visible (Obj_Type)
7217 and then not In_Instance
7218 and then not Is_Private_Overriding (Prim_Op))
7223 Set_Etype (Call_Node, Any_Type);
7224 Set_Is_Overloaded (Call_Node, False);
7226 if No (Matching_Op) then
7227 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
7228 Candidate := Prim_Op;
7230 Set_Parent (Call_Node, Parent (Node_To_Replace));
7232 Set_Name (Call_Node, Prim_Op_Ref);
7238 Report => Report_Error,
7240 Skip_First => True);
7242 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
7244 -- More than one interpretation, collect for subsequent
7245 -- disambiguation. If this is a procedure call and there
7246 -- is another match, report ambiguity now.
7252 Report => Report_Error,
7254 Skip_First => True);
7256 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
7257 and then Nkind (Call_Node) /= N_Function_Call
7259 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
7260 Report_Ambiguity (Matching_Op);
7261 Report_Ambiguity (Prim_Op);
7271 if Present (Matching_Op) then
7272 Set_Etype (Call_Node, Etype (Matching_Op));
7275 return Present (Matching_Op);
7276 end Try_Primitive_Operation;
7278 -- Start of processing for Try_Object_Operation
7281 Analyze_Expression (Obj);
7283 -- Analyze the actuals if node is known to be a subprogram call
7285 if Is_Subprg_Call and then N = Name (Parent (N)) then
7286 Actual := First (Parameter_Associations (Parent (N)));
7287 while Present (Actual) loop
7288 Analyze_Expression (Actual);
7293 -- Build a subprogram call node, using a copy of Obj as its first
7294 -- actual. This is a placeholder, to be replaced by an explicit
7295 -- dereference when needed.
7297 Transform_Object_Operation
7298 (Call_Node => New_Call_Node,
7299 Node_To_Replace => Node_To_Replace);
7301 Set_Etype (New_Call_Node, Any_Type);
7302 Set_Etype (Subprog, Any_Type);
7303 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
7305 if not Is_Overloaded (Obj) then
7306 Try_One_Prefix_Interpretation (Obj_Type);
7313 Get_First_Interp (Obj, I, It);
7314 while Present (It.Nam) loop
7315 Try_One_Prefix_Interpretation (It.Typ);
7316 Get_Next_Interp (I, It);
7321 if Etype (New_Call_Node) /= Any_Type then
7322 Complete_Object_Operation
7323 (Call_Node => New_Call_Node,
7324 Node_To_Replace => Node_To_Replace);
7327 elsif Present (Candidate) then
7329 -- The argument list is not type correct. Re-analyze with error
7330 -- reporting enabled, and use one of the possible candidates.
7331 -- In All_Errors_Mode, re-analyze all failed interpretations.
7333 if All_Errors_Mode then
7334 Report_Error := True;
7335 if Try_Primitive_Operation
7336 (Call_Node => New_Call_Node,
7337 Node_To_Replace => Node_To_Replace)
7340 Try_Class_Wide_Operation
7341 (Call_Node => New_Call_Node,
7342 Node_To_Replace => Node_To_Replace)
7349 (N => New_Call_Node,
7353 Skip_First => True);
7356 -- No need for further errors
7361 -- There was no candidate operation, so report it as an error
7362 -- in the caller: Analyze_Selected_Component.
7366 end Try_Object_Operation;
7372 procedure wpo (T : Entity_Id) is
7377 if not Is_Tagged_Type (T) then
7381 E := First_Elmt (Primitive_Operations (Base_Type (T)));
7382 while Present (E) loop
7384 Write_Int (Int (Op));
7385 Write_Str (" === ");
7386 Write_Name (Chars (Op));
7388 Write_Name (Chars (Scope (Op)));