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;
1141 Dont_Care : Boolean;
1142 Others_Present : Boolean;
1144 procedure Non_Static_Choice_Error (Choice : Node_Id);
1145 -- Error routine invoked by the generic instantiation below when
1146 -- the case expression has a non static choice.
1148 package Case_Choices_Processing is new
1149 Generic_Choices_Processing
1150 (Get_Alternatives => Alternatives,
1151 Get_Choices => Discrete_Choices,
1152 Process_Empty_Choice => No_OP,
1153 Process_Non_Static_Choice => Non_Static_Choice_Error,
1154 Process_Associated_Node => No_OP);
1155 use Case_Choices_Processing;
1157 Case_Table : Choice_Table_Type (1 .. Number_Of_Choices (N));
1159 -----------------------------
1160 -- Non_Static_Choice_Error --
1161 -----------------------------
1163 procedure Non_Static_Choice_Error (Choice : Node_Id) is
1165 Flag_Non_Static_Expr
1166 ("choice given in case expression is not static!", Choice);
1167 end Non_Static_Choice_Error;
1169 -- Start of processing for Analyze_Case_Expression
1172 if Comes_From_Source (N) then
1173 Check_Compiler_Unit (N);
1176 Analyze_And_Resolve (Expr, Any_Discrete);
1177 Check_Unset_Reference (Expr);
1178 Exp_Type := Etype (Expr);
1179 Exp_Btype := Base_Type (Exp_Type);
1181 Alt := First (Alternatives (N));
1182 while Present (Alt) loop
1183 Analyze (Expression (Alt));
1187 if not Is_Overloaded (FirstX) then
1188 Set_Etype (N, Etype (FirstX));
1196 Set_Etype (N, Any_Type);
1198 Get_First_Interp (FirstX, I, It);
1199 while Present (It.Nam) loop
1201 -- For each intepretation of the first expression, we only
1202 -- add the intepretation if every other expression in the
1203 -- case expression alternatives has a compatible type.
1205 Alt := Next (First (Alternatives (N)));
1206 while Present (Alt) loop
1207 exit when not Has_Compatible_Type (Expression (Alt), It.Typ);
1212 Add_One_Interp (N, It.Typ, It.Typ);
1215 Get_Next_Interp (I, It);
1220 Exp_Btype := Base_Type (Exp_Type);
1222 -- The expression must be of a discrete type which must be determinable
1223 -- independently of the context in which the expression occurs, but
1224 -- using the fact that the expression must be of a discrete type.
1225 -- Moreover, the type this expression must not be a character literal
1226 -- (which is always ambiguous).
1228 -- If error already reported by Resolve, nothing more to do
1230 if Exp_Btype = Any_Discrete
1231 or else Exp_Btype = Any_Type
1235 elsif Exp_Btype = Any_Character then
1237 ("character literal as case expression is ambiguous", Expr);
1241 -- If the case expression is a formal object of mode in out, then
1242 -- treat it as having a nonstatic subtype by forcing use of the base
1243 -- type (which has to get passed to Check_Case_Choices below). Also
1244 -- use base type when the case expression is parenthesized.
1246 if Paren_Count (Expr) > 0
1247 or else (Is_Entity_Name (Expr)
1248 and then Ekind (Entity (Expr)) = E_Generic_In_Out_Parameter)
1250 Exp_Type := Exp_Btype;
1253 -- Call instantiated Analyze_Choices which does the rest of the work
1256 (N, Exp_Type, Case_Table, Last_Choice, Dont_Care, Others_Present);
1258 if Exp_Type = Universal_Integer and then not Others_Present then
1260 ("case on universal integer requires OTHERS choice", Expr);
1262 end Analyze_Case_Expression;
1264 ---------------------------
1265 -- Analyze_Comparison_Op --
1266 ---------------------------
1268 procedure Analyze_Comparison_Op (N : Node_Id) is
1269 L : constant Node_Id := Left_Opnd (N);
1270 R : constant Node_Id := Right_Opnd (N);
1271 Op_Id : Entity_Id := Entity (N);
1274 Set_Etype (N, Any_Type);
1275 Candidate_Type := Empty;
1277 Analyze_Expression (L);
1278 Analyze_Expression (R);
1280 if Present (Op_Id) then
1281 if Ekind (Op_Id) = E_Operator then
1282 Find_Comparison_Types (L, R, Op_Id, N);
1284 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1287 if Is_Overloaded (L) then
1288 Set_Etype (L, Intersect_Types (L, R));
1292 Op_Id := Get_Name_Entity_Id (Chars (N));
1293 while Present (Op_Id) loop
1294 if Ekind (Op_Id) = E_Operator then
1295 Find_Comparison_Types (L, R, Op_Id, N);
1297 Analyze_User_Defined_Binary_Op (N, Op_Id);
1300 Op_Id := Homonym (Op_Id);
1305 end Analyze_Comparison_Op;
1307 ---------------------------
1308 -- Analyze_Concatenation --
1309 ---------------------------
1311 procedure Analyze_Concatenation (N : Node_Id) is
1313 -- We wish to avoid deep recursion, because concatenations are often
1314 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
1315 -- operands nonrecursively until we find something that is not a
1316 -- concatenation (A in this case), or has already been analyzed. We
1317 -- analyze that, and then walk back up the tree following Parent
1318 -- pointers, calling Analyze_Concatenation_Rest to do the rest of the
1319 -- work at each level. The Parent pointers allow us to avoid recursion,
1320 -- and thus avoid running out of memory.
1326 Candidate_Type := Empty;
1328 -- The following code is equivalent to:
1330 -- Set_Etype (N, Any_Type);
1331 -- Analyze_Expression (Left_Opnd (N));
1332 -- Analyze_Concatenation_Rest (N);
1334 -- where the Analyze_Expression call recurses back here if the left
1335 -- operand is a concatenation.
1337 -- Walk down left operands
1340 Set_Etype (NN, Any_Type);
1341 L := Left_Opnd (NN);
1342 exit when Nkind (L) /= N_Op_Concat or else Analyzed (L);
1346 -- Now (given the above example) NN is A&B and L is A
1348 -- First analyze L ...
1350 Analyze_Expression (L);
1352 -- ... then walk NN back up until we reach N (where we started), calling
1353 -- Analyze_Concatenation_Rest along the way.
1356 Analyze_Concatenation_Rest (NN);
1360 end Analyze_Concatenation;
1362 --------------------------------
1363 -- Analyze_Concatenation_Rest --
1364 --------------------------------
1366 -- If the only one-dimensional array type in scope is String,
1367 -- this is the resulting type of the operation. Otherwise there
1368 -- will be a concatenation operation defined for each user-defined
1369 -- one-dimensional array.
1371 procedure Analyze_Concatenation_Rest (N : Node_Id) is
1372 L : constant Node_Id := Left_Opnd (N);
1373 R : constant Node_Id := Right_Opnd (N);
1374 Op_Id : Entity_Id := Entity (N);
1379 Analyze_Expression (R);
1381 -- If the entity is present, the node appears in an instance, and
1382 -- denotes a predefined concatenation operation. The resulting type is
1383 -- obtained from the arguments when possible. If the arguments are
1384 -- aggregates, the array type and the concatenation type must be
1387 if Present (Op_Id) then
1388 if Ekind (Op_Id) = E_Operator then
1389 LT := Base_Type (Etype (L));
1390 RT := Base_Type (Etype (R));
1392 if Is_Array_Type (LT)
1393 and then (RT = LT or else RT = Base_Type (Component_Type (LT)))
1395 Add_One_Interp (N, Op_Id, LT);
1397 elsif Is_Array_Type (RT)
1398 and then LT = Base_Type (Component_Type (RT))
1400 Add_One_Interp (N, Op_Id, RT);
1402 -- If one operand is a string type or a user-defined array type,
1403 -- and the other is a literal, result is of the specific type.
1406 (Root_Type (LT) = Standard_String
1407 or else Scope (LT) /= Standard_Standard)
1408 and then Etype (R) = Any_String
1410 Add_One_Interp (N, Op_Id, LT);
1413 (Root_Type (RT) = Standard_String
1414 or else Scope (RT) /= Standard_Standard)
1415 and then Etype (L) = Any_String
1417 Add_One_Interp (N, Op_Id, RT);
1419 elsif not Is_Generic_Type (Etype (Op_Id)) then
1420 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1423 -- Type and its operations must be visible
1425 Set_Entity (N, Empty);
1426 Analyze_Concatenation (N);
1430 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1434 Op_Id := Get_Name_Entity_Id (Name_Op_Concat);
1435 while Present (Op_Id) loop
1436 if Ekind (Op_Id) = E_Operator then
1438 -- Do not consider operators declared in dead code, they can
1439 -- not be part of the resolution.
1441 if Is_Eliminated (Op_Id) then
1444 Find_Concatenation_Types (L, R, Op_Id, N);
1448 Analyze_User_Defined_Binary_Op (N, Op_Id);
1451 Op_Id := Homonym (Op_Id);
1456 end Analyze_Concatenation_Rest;
1458 ------------------------------------
1459 -- Analyze_Conditional_Expression --
1460 ------------------------------------
1462 procedure Analyze_Conditional_Expression (N : Node_Id) is
1463 Condition : constant Node_Id := First (Expressions (N));
1464 Then_Expr : constant Node_Id := Next (Condition);
1465 Else_Expr : Node_Id;
1468 -- Defend against error of missing expressions from previous error
1470 if No (Then_Expr) then
1474 Else_Expr := Next (Then_Expr);
1476 if Comes_From_Source (N) then
1477 Check_Compiler_Unit (N);
1480 Analyze_Expression (Condition);
1481 Analyze_Expression (Then_Expr);
1483 if Present (Else_Expr) then
1484 Analyze_Expression (Else_Expr);
1487 -- If then expression not overloaded, then that decides the type
1489 if not Is_Overloaded (Then_Expr) then
1490 Set_Etype (N, Etype (Then_Expr));
1492 -- Case where then expression is overloaded
1500 Set_Etype (N, Any_Type);
1501 Get_First_Interp (Then_Expr, I, It);
1502 while Present (It.Nam) loop
1504 -- For each possible intepretation of the Then Expression,
1505 -- add it only if the else expression has a compatible type.
1507 -- Is this right if Else_Expr is empty?
1509 if Has_Compatible_Type (Else_Expr, It.Typ) then
1510 Add_One_Interp (N, It.Typ, It.Typ);
1513 Get_Next_Interp (I, It);
1517 end Analyze_Conditional_Expression;
1519 -------------------------
1520 -- Analyze_Equality_Op --
1521 -------------------------
1523 procedure Analyze_Equality_Op (N : Node_Id) is
1524 Loc : constant Source_Ptr := Sloc (N);
1525 L : constant Node_Id := Left_Opnd (N);
1526 R : constant Node_Id := Right_Opnd (N);
1530 Set_Etype (N, Any_Type);
1531 Candidate_Type := Empty;
1533 Analyze_Expression (L);
1534 Analyze_Expression (R);
1536 -- If the entity is set, the node is a generic instance with a non-local
1537 -- reference to the predefined operator or to a user-defined function.
1538 -- It can also be an inequality that is expanded into the negation of a
1539 -- call to a user-defined equality operator.
1541 -- For the predefined case, the result is Boolean, regardless of the
1542 -- type of the operands. The operands may even be limited, if they are
1543 -- generic actuals. If they are overloaded, label the left argument with
1544 -- the common type that must be present, or with the type of the formal
1545 -- of the user-defined function.
1547 if Present (Entity (N)) then
1548 Op_Id := Entity (N);
1550 if Ekind (Op_Id) = E_Operator then
1551 Add_One_Interp (N, Op_Id, Standard_Boolean);
1553 Add_One_Interp (N, Op_Id, Etype (Op_Id));
1556 if Is_Overloaded (L) then
1557 if Ekind (Op_Id) = E_Operator then
1558 Set_Etype (L, Intersect_Types (L, R));
1560 Set_Etype (L, Etype (First_Formal (Op_Id)));
1565 Op_Id := Get_Name_Entity_Id (Chars (N));
1566 while Present (Op_Id) loop
1567 if Ekind (Op_Id) = E_Operator then
1568 Find_Equality_Types (L, R, Op_Id, N);
1570 Analyze_User_Defined_Binary_Op (N, Op_Id);
1573 Op_Id := Homonym (Op_Id);
1577 -- If there was no match, and the operator is inequality, this may
1578 -- be a case where inequality has not been made explicit, as for
1579 -- tagged types. Analyze the node as the negation of an equality
1580 -- operation. This cannot be done earlier, because before analysis
1581 -- we cannot rule out the presence of an explicit inequality.
1583 if Etype (N) = Any_Type
1584 and then Nkind (N) = N_Op_Ne
1586 Op_Id := Get_Name_Entity_Id (Name_Op_Eq);
1587 while Present (Op_Id) loop
1588 if Ekind (Op_Id) = E_Operator then
1589 Find_Equality_Types (L, R, Op_Id, N);
1591 Analyze_User_Defined_Binary_Op (N, Op_Id);
1594 Op_Id := Homonym (Op_Id);
1597 if Etype (N) /= Any_Type then
1598 Op_Id := Entity (N);
1604 Left_Opnd => Left_Opnd (N),
1605 Right_Opnd => Right_Opnd (N))));
1607 Set_Entity (Right_Opnd (N), Op_Id);
1613 end Analyze_Equality_Op;
1615 ----------------------------------
1616 -- Analyze_Explicit_Dereference --
1617 ----------------------------------
1619 procedure Analyze_Explicit_Dereference (N : Node_Id) is
1620 Loc : constant Source_Ptr := Sloc (N);
1621 P : constant Node_Id := Prefix (N);
1627 function Is_Function_Type return Boolean;
1628 -- Check whether node may be interpreted as an implicit function call
1630 ----------------------
1631 -- Is_Function_Type --
1632 ----------------------
1634 function Is_Function_Type return Boolean is
1639 if not Is_Overloaded (N) then
1640 return Ekind (Base_Type (Etype (N))) = E_Subprogram_Type
1641 and then Etype (Base_Type (Etype (N))) /= Standard_Void_Type;
1644 Get_First_Interp (N, I, It);
1645 while Present (It.Nam) loop
1646 if Ekind (Base_Type (It.Typ)) /= E_Subprogram_Type
1647 or else Etype (Base_Type (It.Typ)) = Standard_Void_Type
1652 Get_Next_Interp (I, It);
1657 end Is_Function_Type;
1659 -- Start of processing for Analyze_Explicit_Dereference
1663 Set_Etype (N, Any_Type);
1665 -- Test for remote access to subprogram type, and if so return
1666 -- after rewriting the original tree.
1668 if Remote_AST_E_Dereference (P) then
1672 -- Normal processing for other than remote access to subprogram type
1674 if not Is_Overloaded (P) then
1675 if Is_Access_Type (Etype (P)) then
1677 -- Set the Etype. We need to go through Is_For_Access_Subtypes to
1678 -- avoid other problems caused by the Private_Subtype and it is
1679 -- safe to go to the Base_Type because this is the same as
1680 -- converting the access value to its Base_Type.
1683 DT : Entity_Id := Designated_Type (Etype (P));
1686 if Ekind (DT) = E_Private_Subtype
1687 and then Is_For_Access_Subtype (DT)
1689 DT := Base_Type (DT);
1692 -- An explicit dereference is a legal occurrence of an
1693 -- incomplete type imported through a limited_with clause,
1694 -- if the full view is visible.
1696 if From_With_Type (DT)
1697 and then not From_With_Type (Scope (DT))
1699 (Is_Immediately_Visible (Scope (DT))
1701 (Is_Child_Unit (Scope (DT))
1702 and then Is_Visible_Child_Unit (Scope (DT))))
1704 Set_Etype (N, Available_View (DT));
1711 elsif Etype (P) /= Any_Type then
1712 Error_Msg_N ("prefix of dereference must be an access type", N);
1717 Get_First_Interp (P, I, It);
1718 while Present (It.Nam) loop
1721 if Is_Access_Type (T) then
1722 Add_One_Interp (N, Designated_Type (T), Designated_Type (T));
1725 Get_Next_Interp (I, It);
1728 -- Error if no interpretation of the prefix has an access type
1730 if Etype (N) = Any_Type then
1732 ("access type required in prefix of explicit dereference", P);
1733 Set_Etype (N, Any_Type);
1739 and then Nkind (Parent (N)) /= N_Indexed_Component
1741 and then (Nkind (Parent (N)) /= N_Function_Call
1742 or else N /= Name (Parent (N)))
1744 and then (Nkind (Parent (N)) /= N_Procedure_Call_Statement
1745 or else N /= Name (Parent (N)))
1747 and then Nkind (Parent (N)) /= N_Subprogram_Renaming_Declaration
1748 and then (Nkind (Parent (N)) /= N_Attribute_Reference
1750 (Attribute_Name (Parent (N)) /= Name_Address
1752 Attribute_Name (Parent (N)) /= Name_Access))
1754 -- Name is a function call with no actuals, in a context that
1755 -- requires deproceduring (including as an actual in an enclosing
1756 -- function or procedure call). There are some pathological cases
1757 -- where the prefix might include functions that return access to
1758 -- subprograms and others that return a regular type. Disambiguation
1759 -- of those has to take place in Resolve.
1762 Make_Function_Call (Loc,
1763 Name => Make_Explicit_Dereference (Loc, P),
1764 Parameter_Associations => New_List);
1766 -- If the prefix is overloaded, remove operations that have formals,
1767 -- we know that this is a parameterless call.
1769 if Is_Overloaded (P) then
1770 Get_First_Interp (P, I, It);
1771 while Present (It.Nam) loop
1774 if No (First_Formal (Base_Type (Designated_Type (T)))) then
1780 Get_Next_Interp (I, It);
1787 elsif not Is_Function_Type
1788 and then Is_Overloaded (N)
1790 -- The prefix may include access to subprograms and other access
1791 -- types. If the context selects the interpretation that is a
1792 -- function call (not a procedure call) we cannot rewrite the node
1793 -- yet, but we include the result of the call interpretation.
1795 Get_First_Interp (N, I, It);
1796 while Present (It.Nam) loop
1797 if Ekind (Base_Type (It.Typ)) = E_Subprogram_Type
1798 and then Etype (Base_Type (It.Typ)) /= Standard_Void_Type
1799 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
1801 Add_One_Interp (N, Etype (It.Typ), Etype (It.Typ));
1804 Get_Next_Interp (I, It);
1808 -- A value of remote access-to-class-wide must not be dereferenced
1811 Validate_Remote_Access_To_Class_Wide_Type (N);
1812 end Analyze_Explicit_Dereference;
1814 ------------------------
1815 -- Analyze_Expression --
1816 ------------------------
1818 procedure Analyze_Expression (N : Node_Id) is
1821 Check_Parameterless_Call (N);
1822 end Analyze_Expression;
1824 -------------------------------------
1825 -- Analyze_Expression_With_Actions --
1826 -------------------------------------
1828 procedure Analyze_Expression_With_Actions (N : Node_Id) is
1832 A := First (Actions (N));
1839 Analyze_Expression (Expression (N));
1840 Set_Etype (N, Etype (Expression (N)));
1841 end Analyze_Expression_With_Actions;
1843 ------------------------------------
1844 -- Analyze_Indexed_Component_Form --
1845 ------------------------------------
1847 procedure Analyze_Indexed_Component_Form (N : Node_Id) is
1848 P : constant Node_Id := Prefix (N);
1849 Exprs : constant List_Id := Expressions (N);
1855 procedure Process_Function_Call;
1856 -- Prefix in indexed component form is an overloadable entity,
1857 -- so the node is a function call. Reformat it as such.
1859 procedure Process_Indexed_Component;
1860 -- Prefix in indexed component form is actually an indexed component.
1861 -- This routine processes it, knowing that the prefix is already
1864 procedure Process_Indexed_Component_Or_Slice;
1865 -- An indexed component with a single index may designate a slice if
1866 -- the index is a subtype mark. This routine disambiguates these two
1867 -- cases by resolving the prefix to see if it is a subtype mark.
1869 procedure Process_Overloaded_Indexed_Component;
1870 -- If the prefix of an indexed component is overloaded, the proper
1871 -- interpretation is selected by the index types and the context.
1873 ---------------------------
1874 -- Process_Function_Call --
1875 ---------------------------
1877 procedure Process_Function_Call is
1881 Change_Node (N, N_Function_Call);
1883 Set_Parameter_Associations (N, Exprs);
1885 -- Analyze actuals prior to analyzing the call itself
1887 Actual := First (Parameter_Associations (N));
1888 while Present (Actual) loop
1890 Check_Parameterless_Call (Actual);
1892 -- Move to next actual. Note that we use Next, not Next_Actual
1893 -- here. The reason for this is a bit subtle. If a function call
1894 -- includes named associations, the parser recognizes the node as
1895 -- a call, and it is analyzed as such. If all associations are
1896 -- positional, the parser builds an indexed_component node, and
1897 -- it is only after analysis of the prefix that the construct
1898 -- is recognized as a call, in which case Process_Function_Call
1899 -- rewrites the node and analyzes the actuals. If the list of
1900 -- actuals is malformed, the parser may leave the node as an
1901 -- indexed component (despite the presence of named associations).
1902 -- The iterator Next_Actual is equivalent to Next if the list is
1903 -- positional, but follows the normalized chain of actuals when
1904 -- named associations are present. In this case normalization has
1905 -- not taken place, and actuals remain unanalyzed, which leads to
1906 -- subsequent crashes or loops if there is an attempt to continue
1907 -- analysis of the program.
1913 end Process_Function_Call;
1915 -------------------------------
1916 -- Process_Indexed_Component --
1917 -------------------------------
1919 procedure Process_Indexed_Component is
1921 Array_Type : Entity_Id;
1923 Pent : Entity_Id := Empty;
1926 Exp := First (Exprs);
1928 if Is_Overloaded (P) then
1929 Process_Overloaded_Indexed_Component;
1932 Array_Type := Etype (P);
1934 if Is_Entity_Name (P) then
1936 elsif Nkind (P) = N_Selected_Component
1937 and then Is_Entity_Name (Selector_Name (P))
1939 Pent := Entity (Selector_Name (P));
1942 -- Prefix must be appropriate for an array type, taking into
1943 -- account a possible implicit dereference.
1945 if Is_Access_Type (Array_Type) then
1946 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
1947 Array_Type := Process_Implicit_Dereference_Prefix (Pent, P);
1950 if Is_Array_Type (Array_Type) then
1953 elsif Present (Pent) and then Ekind (Pent) = E_Entry_Family then
1955 Set_Etype (N, Any_Type);
1957 if not Has_Compatible_Type
1958 (Exp, Entry_Index_Type (Pent))
1960 Error_Msg_N ("invalid index type in entry name", N);
1962 elsif Present (Next (Exp)) then
1963 Error_Msg_N ("too many subscripts in entry reference", N);
1966 Set_Etype (N, Etype (P));
1971 elsif Is_Record_Type (Array_Type)
1972 and then Remote_AST_I_Dereference (P)
1976 elsif Array_Type = Any_Type then
1977 Set_Etype (N, Any_Type);
1979 -- In most cases the analysis of the prefix will have emitted
1980 -- an error already, but if the prefix may be interpreted as a
1981 -- call in prefixed notation, the report is left to the caller.
1982 -- To prevent cascaded errors, report only if no previous ones.
1984 if Serious_Errors_Detected = 0 then
1985 Error_Msg_N ("invalid prefix in indexed component", P);
1987 if Nkind (P) = N_Expanded_Name then
1988 Error_Msg_NE ("\& is not visible", P, Selector_Name (P));
1994 -- Here we definitely have a bad indexing
1997 if Nkind (Parent (N)) = N_Requeue_Statement
1998 and then Present (Pent) and then Ekind (Pent) = E_Entry
2001 ("REQUEUE does not permit parameters", First (Exprs));
2003 elsif Is_Entity_Name (P)
2004 and then Etype (P) = Standard_Void_Type
2006 Error_Msg_NE ("incorrect use of&", P, Entity (P));
2009 Error_Msg_N ("array type required in indexed component", P);
2012 Set_Etype (N, Any_Type);
2016 Index := First_Index (Array_Type);
2017 while Present (Index) and then Present (Exp) loop
2018 if not Has_Compatible_Type (Exp, Etype (Index)) then
2019 Wrong_Type (Exp, Etype (Index));
2020 Set_Etype (N, Any_Type);
2028 Set_Etype (N, Component_Type (Array_Type));
2030 if Present (Index) then
2032 ("too few subscripts in array reference", First (Exprs));
2034 elsif Present (Exp) then
2035 Error_Msg_N ("too many subscripts in array reference", Exp);
2038 end Process_Indexed_Component;
2040 ----------------------------------------
2041 -- Process_Indexed_Component_Or_Slice --
2042 ----------------------------------------
2044 procedure Process_Indexed_Component_Or_Slice is
2046 Exp := First (Exprs);
2047 while Present (Exp) loop
2048 Analyze_Expression (Exp);
2052 Exp := First (Exprs);
2054 -- If one index is present, and it is a subtype name, then the
2055 -- node denotes a slice (note that the case of an explicit range
2056 -- for a slice was already built as an N_Slice node in the first
2057 -- place, so that case is not handled here).
2059 -- We use a replace rather than a rewrite here because this is one
2060 -- of the cases in which the tree built by the parser is plain wrong.
2063 and then Is_Entity_Name (Exp)
2064 and then Is_Type (Entity (Exp))
2067 Make_Slice (Sloc (N),
2069 Discrete_Range => New_Copy (Exp)));
2072 -- Otherwise (more than one index present, or single index is not
2073 -- a subtype name), then we have the indexed component case.
2076 Process_Indexed_Component;
2078 end Process_Indexed_Component_Or_Slice;
2080 ------------------------------------------
2081 -- Process_Overloaded_Indexed_Component --
2082 ------------------------------------------
2084 procedure Process_Overloaded_Indexed_Component is
2093 Set_Etype (N, Any_Type);
2095 Get_First_Interp (P, I, It);
2096 while Present (It.Nam) loop
2099 if Is_Access_Type (Typ) then
2100 Typ := Designated_Type (Typ);
2101 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
2104 if Is_Array_Type (Typ) then
2106 -- Got a candidate: verify that index types are compatible
2108 Index := First_Index (Typ);
2110 Exp := First (Exprs);
2111 while Present (Index) and then Present (Exp) loop
2112 if Has_Compatible_Type (Exp, Etype (Index)) then
2124 if Found and then No (Index) and then No (Exp) then
2126 Etype (Component_Type (Typ)),
2127 Etype (Component_Type (Typ)));
2131 Get_Next_Interp (I, It);
2134 if Etype (N) = Any_Type then
2135 Error_Msg_N ("no legal interpretation for indexed component", N);
2136 Set_Is_Overloaded (N, False);
2140 end Process_Overloaded_Indexed_Component;
2142 -- Start of processing for Analyze_Indexed_Component_Form
2145 -- Get name of array, function or type
2149 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement) then
2151 -- If P is an explicit dereference whose prefix is of a
2152 -- remote access-to-subprogram type, then N has already
2153 -- been rewritten as a subprogram call and analyzed.
2158 pragma Assert (Nkind (N) = N_Indexed_Component);
2160 P_T := Base_Type (Etype (P));
2162 if Is_Entity_Name (P) then
2165 if Is_Type (U_N) then
2167 -- Reformat node as a type conversion
2169 E := Remove_Head (Exprs);
2171 if Present (First (Exprs)) then
2173 ("argument of type conversion must be single expression", N);
2176 Change_Node (N, N_Type_Conversion);
2177 Set_Subtype_Mark (N, P);
2179 Set_Expression (N, E);
2181 -- After changing the node, call for the specific Analysis
2182 -- routine directly, to avoid a double call to the expander.
2184 Analyze_Type_Conversion (N);
2188 if Is_Overloadable (U_N) then
2189 Process_Function_Call;
2191 elsif Ekind (Etype (P)) = E_Subprogram_Type
2192 or else (Is_Access_Type (Etype (P))
2194 Ekind (Designated_Type (Etype (P))) =
2197 -- Call to access_to-subprogram with possible implicit dereference
2199 Process_Function_Call;
2201 elsif Is_Generic_Subprogram (U_N) then
2203 -- A common beginner's (or C++ templates fan) error
2205 Error_Msg_N ("generic subprogram cannot be called", N);
2206 Set_Etype (N, Any_Type);
2210 Process_Indexed_Component_Or_Slice;
2213 -- If not an entity name, prefix is an expression that may denote
2214 -- an array or an access-to-subprogram.
2217 if Ekind (P_T) = E_Subprogram_Type
2218 or else (Is_Access_Type (P_T)
2220 Ekind (Designated_Type (P_T)) = E_Subprogram_Type)
2222 Process_Function_Call;
2224 elsif Nkind (P) = N_Selected_Component
2225 and then Is_Overloadable (Entity (Selector_Name (P)))
2227 Process_Function_Call;
2230 -- Indexed component, slice, or a call to a member of a family
2231 -- entry, which will be converted to an entry call later.
2233 Process_Indexed_Component_Or_Slice;
2236 end Analyze_Indexed_Component_Form;
2238 ------------------------
2239 -- Analyze_Logical_Op --
2240 ------------------------
2242 procedure Analyze_Logical_Op (N : Node_Id) is
2243 L : constant Node_Id := Left_Opnd (N);
2244 R : constant Node_Id := Right_Opnd (N);
2245 Op_Id : Entity_Id := Entity (N);
2248 Set_Etype (N, Any_Type);
2249 Candidate_Type := Empty;
2251 Analyze_Expression (L);
2252 Analyze_Expression (R);
2254 if Present (Op_Id) then
2256 if Ekind (Op_Id) = E_Operator then
2257 Find_Boolean_Types (L, R, Op_Id, N);
2259 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2263 Op_Id := Get_Name_Entity_Id (Chars (N));
2264 while Present (Op_Id) loop
2265 if Ekind (Op_Id) = E_Operator then
2266 Find_Boolean_Types (L, R, Op_Id, N);
2268 Analyze_User_Defined_Binary_Op (N, Op_Id);
2271 Op_Id := Homonym (Op_Id);
2276 end Analyze_Logical_Op;
2278 ---------------------------
2279 -- Analyze_Membership_Op --
2280 ---------------------------
2282 procedure Analyze_Membership_Op (N : Node_Id) is
2283 L : constant Node_Id := Left_Opnd (N);
2284 R : constant Node_Id := Right_Opnd (N);
2286 Index : Interp_Index;
2288 Found : Boolean := False;
2292 procedure Try_One_Interp (T1 : Entity_Id);
2293 -- Routine to try one proposed interpretation. Note that the context
2294 -- of the operation plays no role in resolving the arguments, so that
2295 -- if there is more than one interpretation of the operands that is
2296 -- compatible with a membership test, the operation is ambiguous.
2298 --------------------
2299 -- Try_One_Interp --
2300 --------------------
2302 procedure Try_One_Interp (T1 : Entity_Id) is
2304 if Has_Compatible_Type (R, T1) then
2306 and then Base_Type (T1) /= Base_Type (T_F)
2308 It := Disambiguate (L, I_F, Index, Any_Type);
2310 if It = No_Interp then
2311 Ambiguous_Operands (N);
2312 Set_Etype (L, Any_Type);
2329 procedure Analyze_Set_Membership;
2330 -- If a set of alternatives is present, analyze each and find the
2331 -- common type to which they must all resolve.
2333 ----------------------------
2334 -- Analyze_Set_Membership --
2335 ----------------------------
2337 procedure Analyze_Set_Membership is
2339 Index : Interp_Index;
2341 Candidate_Interps : Node_Id;
2342 Common_Type : Entity_Id := Empty;
2346 Candidate_Interps := L;
2348 if not Is_Overloaded (L) then
2349 Common_Type := Etype (L);
2351 Alt := First (Alternatives (N));
2352 while Present (Alt) loop
2355 if not Has_Compatible_Type (Alt, Common_Type) then
2356 Wrong_Type (Alt, Common_Type);
2363 Alt := First (Alternatives (N));
2364 while Present (Alt) loop
2366 if not Is_Overloaded (Alt) then
2367 Common_Type := Etype (Alt);
2370 Get_First_Interp (Alt, Index, It);
2371 while Present (It.Typ) loop
2373 Has_Compatible_Type (Candidate_Interps, It.Typ)
2375 Remove_Interp (Index);
2378 Get_Next_Interp (Index, It);
2381 Get_First_Interp (Alt, Index, It);
2384 Error_Msg_N ("alternative has no legal type", Alt);
2388 -- If alternative is not overloaded, we have a unique type
2391 Set_Etype (Alt, It.Typ);
2392 Get_Next_Interp (Index, It);
2395 Set_Is_Overloaded (Alt, False);
2396 Common_Type := Etype (Alt);
2399 Candidate_Interps := Alt;
2406 Set_Etype (N, Standard_Boolean);
2408 if Present (Common_Type) then
2409 Set_Etype (L, Common_Type);
2410 Set_Is_Overloaded (L, False);
2413 Error_Msg_N ("cannot resolve membership operation", N);
2415 end Analyze_Set_Membership;
2417 -- Start of processing for Analyze_Membership_Op
2420 Analyze_Expression (L);
2423 and then Ada_Version >= Ada_2012
2425 Analyze_Set_Membership;
2429 if Nkind (R) = N_Range
2430 or else (Nkind (R) = N_Attribute_Reference
2431 and then Attribute_Name (R) = Name_Range)
2435 if not Is_Overloaded (L) then
2436 Try_One_Interp (Etype (L));
2439 Get_First_Interp (L, Index, It);
2440 while Present (It.Typ) loop
2441 Try_One_Interp (It.Typ);
2442 Get_Next_Interp (Index, It);
2446 -- If not a range, it can only be a subtype mark, or else there
2447 -- is a more basic error, to be diagnosed in Find_Type.
2452 if Is_Entity_Name (R) then
2453 Check_Fully_Declared (Entity (R), R);
2457 -- Compatibility between expression and subtype mark or range is
2458 -- checked during resolution. The result of the operation is Boolean
2461 Set_Etype (N, Standard_Boolean);
2463 if Comes_From_Source (N)
2464 and then Present (Right_Opnd (N))
2465 and then Is_CPP_Class (Etype (Etype (Right_Opnd (N))))
2467 Error_Msg_N ("membership test not applicable to cpp-class types", N);
2469 end Analyze_Membership_Op;
2471 ----------------------
2472 -- Analyze_Negation --
2473 ----------------------
2475 procedure Analyze_Negation (N : Node_Id) is
2476 R : constant Node_Id := Right_Opnd (N);
2477 Op_Id : Entity_Id := Entity (N);
2480 Set_Etype (N, Any_Type);
2481 Candidate_Type := Empty;
2483 Analyze_Expression (R);
2485 if Present (Op_Id) then
2486 if Ekind (Op_Id) = E_Operator then
2487 Find_Negation_Types (R, Op_Id, N);
2489 Add_One_Interp (N, Op_Id, Etype (Op_Id));
2493 Op_Id := Get_Name_Entity_Id (Chars (N));
2494 while Present (Op_Id) loop
2495 if Ekind (Op_Id) = E_Operator then
2496 Find_Negation_Types (R, Op_Id, N);
2498 Analyze_User_Defined_Unary_Op (N, Op_Id);
2501 Op_Id := Homonym (Op_Id);
2506 end Analyze_Negation;
2512 procedure Analyze_Null (N : Node_Id) is
2514 Set_Etype (N, Any_Access);
2517 ----------------------
2518 -- Analyze_One_Call --
2519 ----------------------
2521 procedure Analyze_One_Call
2525 Success : out Boolean;
2526 Skip_First : Boolean := False)
2528 Actuals : constant List_Id := Parameter_Associations (N);
2529 Prev_T : constant Entity_Id := Etype (N);
2531 Must_Skip : constant Boolean := Skip_First
2532 or else Nkind (Original_Node (N)) = N_Selected_Component
2534 (Nkind (Original_Node (N)) = N_Indexed_Component
2535 and then Nkind (Prefix (Original_Node (N)))
2536 = N_Selected_Component);
2537 -- The first formal must be omitted from the match when trying to find
2538 -- a primitive operation that is a possible interpretation, and also
2539 -- after the call has been rewritten, because the corresponding actual
2540 -- is already known to be compatible, and because this may be an
2541 -- indexing of a call with default parameters.
2545 Is_Indexed : Boolean := False;
2546 Is_Indirect : Boolean := False;
2547 Subp_Type : constant Entity_Id := Etype (Nam);
2550 function Operator_Hidden_By (Fun : Entity_Id) return Boolean;
2551 -- There may be a user-defined operator that hides the current
2552 -- interpretation. We must check for this independently of the
2553 -- analysis of the call with the user-defined operation, because
2554 -- the parameter names may be wrong and yet the hiding takes place.
2555 -- This fixes a problem with ACATS test B34014O.
2557 -- When the type Address is a visible integer type, and the DEC
2558 -- system extension is visible, the predefined operator may be
2559 -- hidden as well, by one of the address operations in auxdec.
2560 -- Finally, The abstract operations on address do not hide the
2561 -- predefined operator (this is the purpose of making them abstract).
2563 procedure Indicate_Name_And_Type;
2564 -- If candidate interpretation matches, indicate name and type of
2565 -- result on call node.
2567 ----------------------------
2568 -- Indicate_Name_And_Type --
2569 ----------------------------
2571 procedure Indicate_Name_And_Type is
2573 Add_One_Interp (N, Nam, Etype (Nam));
2576 -- If the prefix of the call is a name, indicate the entity
2577 -- being called. If it is not a name, it is an expression that
2578 -- denotes an access to subprogram or else an entry or family. In
2579 -- the latter case, the name is a selected component, and the entity
2580 -- being called is noted on the selector.
2582 if not Is_Type (Nam) then
2583 if Is_Entity_Name (Name (N)) then
2584 Set_Entity (Name (N), Nam);
2586 elsif Nkind (Name (N)) = N_Selected_Component then
2587 Set_Entity (Selector_Name (Name (N)), Nam);
2591 if Debug_Flag_E and not Report then
2592 Write_Str (" Overloaded call ");
2593 Write_Int (Int (N));
2594 Write_Str (" compatible with ");
2595 Write_Int (Int (Nam));
2598 end Indicate_Name_And_Type;
2600 ------------------------
2601 -- Operator_Hidden_By --
2602 ------------------------
2604 function Operator_Hidden_By (Fun : Entity_Id) return Boolean is
2605 Act1 : constant Node_Id := First_Actual (N);
2606 Act2 : constant Node_Id := Next_Actual (Act1);
2607 Form1 : constant Entity_Id := First_Formal (Fun);
2608 Form2 : constant Entity_Id := Next_Formal (Form1);
2611 if Ekind (Fun) /= E_Function
2612 or else Is_Abstract_Subprogram (Fun)
2616 elsif not Has_Compatible_Type (Act1, Etype (Form1)) then
2619 elsif Present (Form2) then
2621 No (Act2) or else not Has_Compatible_Type (Act2, Etype (Form2))
2626 elsif Present (Act2) then
2630 -- Now we know that the arity of the operator matches the function,
2631 -- and the function call is a valid interpretation. The function
2632 -- hides the operator if it has the right signature, or if one of
2633 -- its operands is a non-abstract operation on Address when this is
2634 -- a visible integer type.
2636 return Hides_Op (Fun, Nam)
2637 or else Is_Descendent_Of_Address (Etype (Form1))
2640 and then Is_Descendent_Of_Address (Etype (Form2)));
2641 end Operator_Hidden_By;
2643 -- Start of processing for Analyze_One_Call
2648 -- If the subprogram has no formals or if all the formals have defaults,
2649 -- and the return type is an array type, the node may denote an indexing
2650 -- of the result of a parameterless call. In Ada 2005, the subprogram
2651 -- may have one non-defaulted formal, and the call may have been written
2652 -- in prefix notation, so that the rebuilt parameter list has more than
2655 if not Is_Overloadable (Nam)
2656 and then Ekind (Nam) /= E_Subprogram_Type
2657 and then Ekind (Nam) /= E_Entry_Family
2662 -- An indexing requires at least one actual
2664 if not Is_Empty_List (Actuals)
2666 (Needs_No_Actuals (Nam)
2668 (Needs_One_Actual (Nam)
2669 and then Present (Next_Actual (First (Actuals)))))
2671 if Is_Array_Type (Subp_Type) then
2672 Is_Indexed := Try_Indexed_Call (N, Nam, Subp_Type, Must_Skip);
2674 elsif Is_Access_Type (Subp_Type)
2675 and then Is_Array_Type (Designated_Type (Subp_Type))
2679 (N, Nam, Designated_Type (Subp_Type), Must_Skip);
2681 -- The prefix can also be a parameterless function that returns an
2682 -- access to subprogram, in which case this is an indirect call.
2683 -- If this succeeds, an explicit dereference is added later on,
2684 -- in Analyze_Call or Resolve_Call.
2686 elsif Is_Access_Type (Subp_Type)
2687 and then Ekind (Designated_Type (Subp_Type)) = E_Subprogram_Type
2689 Is_Indirect := Try_Indirect_Call (N, Nam, Subp_Type);
2694 -- If the call has been transformed into a slice, it is of the form
2695 -- F (Subtype) where F is parameterless. The node has been rewritten in
2696 -- Try_Indexed_Call and there is nothing else to do.
2699 and then Nkind (N) = N_Slice
2705 (N, Nam, (Report and not Is_Indexed and not Is_Indirect), Norm_OK);
2709 -- If an indirect call is a possible interpretation, indicate
2710 -- success to the caller.
2716 -- Mismatch in number or names of parameters
2718 elsif Debug_Flag_E then
2719 Write_Str (" normalization fails in call ");
2720 Write_Int (Int (N));
2721 Write_Str (" with subprogram ");
2722 Write_Int (Int (Nam));
2726 -- If the context expects a function call, discard any interpretation
2727 -- that is a procedure. If the node is not overloaded, leave as is for
2728 -- better error reporting when type mismatch is found.
2730 elsif Nkind (N) = N_Function_Call
2731 and then Is_Overloaded (Name (N))
2732 and then Ekind (Nam) = E_Procedure
2736 -- Ditto for function calls in a procedure context
2738 elsif Nkind (N) = N_Procedure_Call_Statement
2739 and then Is_Overloaded (Name (N))
2740 and then Etype (Nam) /= Standard_Void_Type
2744 elsif No (Actuals) then
2746 -- If Normalize succeeds, then there are default parameters for
2749 Indicate_Name_And_Type;
2751 elsif Ekind (Nam) = E_Operator then
2752 if Nkind (N) = N_Procedure_Call_Statement then
2756 -- This can occur when the prefix of the call is an operator
2757 -- name or an expanded name whose selector is an operator name.
2759 Analyze_Operator_Call (N, Nam);
2761 if Etype (N) /= Prev_T then
2763 -- Check that operator is not hidden by a function interpretation
2765 if Is_Overloaded (Name (N)) then
2771 Get_First_Interp (Name (N), I, It);
2772 while Present (It.Nam) loop
2773 if Operator_Hidden_By (It.Nam) then
2774 Set_Etype (N, Prev_T);
2778 Get_Next_Interp (I, It);
2783 -- If operator matches formals, record its name on the call.
2784 -- If the operator is overloaded, Resolve will select the
2785 -- correct one from the list of interpretations. The call
2786 -- node itself carries the first candidate.
2788 Set_Entity (Name (N), Nam);
2791 elsif Report and then Etype (N) = Any_Type then
2792 Error_Msg_N ("incompatible arguments for operator", N);
2796 -- Normalize_Actuals has chained the named associations in the
2797 -- correct order of the formals.
2799 Actual := First_Actual (N);
2800 Formal := First_Formal (Nam);
2802 -- If we are analyzing a call rewritten from object notation,
2803 -- skip first actual, which may be rewritten later as an
2804 -- explicit dereference.
2807 Next_Actual (Actual);
2808 Next_Formal (Formal);
2811 while Present (Actual) and then Present (Formal) loop
2812 if Nkind (Parent (Actual)) /= N_Parameter_Association
2813 or else Chars (Selector_Name (Parent (Actual))) = Chars (Formal)
2815 -- The actual can be compatible with the formal, but we must
2816 -- also check that the context is not an address type that is
2817 -- visibly an integer type, as is the case in VMS_64. In this
2818 -- case the use of literals is illegal, except in the body of
2819 -- descendents of system, where arithmetic operations on
2820 -- address are of course used.
2822 if Has_Compatible_Type (Actual, Etype (Formal))
2824 (Etype (Actual) /= Universal_Integer
2825 or else not Is_Descendent_Of_Address (Etype (Formal))
2827 Is_Predefined_File_Name
2828 (Unit_File_Name (Get_Source_Unit (N))))
2830 Next_Actual (Actual);
2831 Next_Formal (Formal);
2834 if Debug_Flag_E then
2835 Write_Str (" type checking fails in call ");
2836 Write_Int (Int (N));
2837 Write_Str (" with formal ");
2838 Write_Int (Int (Formal));
2839 Write_Str (" in subprogram ");
2840 Write_Int (Int (Nam));
2844 if Report and not Is_Indexed and not Is_Indirect then
2846 -- Ada 2005 (AI-251): Complete the error notification
2847 -- to help new Ada 2005 users.
2849 if Is_Class_Wide_Type (Etype (Formal))
2850 and then Is_Interface (Etype (Etype (Formal)))
2851 and then not Interface_Present_In_Ancestor
2852 (Typ => Etype (Actual),
2853 Iface => Etype (Etype (Formal)))
2856 ("(Ada 2005) does not implement interface }",
2857 Actual, Etype (Etype (Formal)));
2860 Wrong_Type (Actual, Etype (Formal));
2862 if Nkind (Actual) = N_Op_Eq
2863 and then Nkind (Left_Opnd (Actual)) = N_Identifier
2865 Formal := First_Formal (Nam);
2866 while Present (Formal) loop
2867 if Chars (Left_Opnd (Actual)) = Chars (Formal) then
2868 Error_Msg_N -- CODEFIX
2869 ("possible misspelling of `='>`!", Actual);
2873 Next_Formal (Formal);
2877 if All_Errors_Mode then
2878 Error_Msg_Sloc := Sloc (Nam);
2880 if Etype (Formal) = Any_Type then
2882 ("there is no legal actual parameter", Actual);
2885 if Is_Overloadable (Nam)
2886 and then Present (Alias (Nam))
2887 and then not Comes_From_Source (Nam)
2890 ("\\ =='> in call to inherited operation & #!",
2893 elsif Ekind (Nam) = E_Subprogram_Type then
2895 Access_To_Subprogram_Typ :
2896 constant Entity_Id :=
2898 (Associated_Node_For_Itype (Nam));
2901 "\\ =='> in call to dereference of &#!",
2902 Actual, Access_To_Subprogram_Typ);
2907 ("\\ =='> in call to &#!", Actual, Nam);
2917 -- Normalize_Actuals has verified that a default value exists
2918 -- for this formal. Current actual names a subsequent formal.
2920 Next_Formal (Formal);
2924 -- On exit, all actuals match
2926 Indicate_Name_And_Type;
2928 end Analyze_One_Call;
2930 ---------------------------
2931 -- Analyze_Operator_Call --
2932 ---------------------------
2934 procedure Analyze_Operator_Call (N : Node_Id; Op_Id : Entity_Id) is
2935 Op_Name : constant Name_Id := Chars (Op_Id);
2936 Act1 : constant Node_Id := First_Actual (N);
2937 Act2 : constant Node_Id := Next_Actual (Act1);
2940 -- Binary operator case
2942 if Present (Act2) then
2944 -- If more than two operands, then not binary operator after all
2946 if Present (Next_Actual (Act2)) then
2949 elsif Op_Name = Name_Op_Add
2950 or else Op_Name = Name_Op_Subtract
2951 or else Op_Name = Name_Op_Multiply
2952 or else Op_Name = Name_Op_Divide
2953 or else Op_Name = Name_Op_Mod
2954 or else Op_Name = Name_Op_Rem
2955 or else Op_Name = Name_Op_Expon
2957 Find_Arithmetic_Types (Act1, Act2, Op_Id, N);
2959 elsif Op_Name = Name_Op_And
2960 or else Op_Name = Name_Op_Or
2961 or else Op_Name = Name_Op_Xor
2963 Find_Boolean_Types (Act1, Act2, Op_Id, N);
2965 elsif Op_Name = Name_Op_Lt
2966 or else Op_Name = Name_Op_Le
2967 or else Op_Name = Name_Op_Gt
2968 or else Op_Name = Name_Op_Ge
2970 Find_Comparison_Types (Act1, Act2, Op_Id, N);
2972 elsif Op_Name = Name_Op_Eq
2973 or else Op_Name = Name_Op_Ne
2975 Find_Equality_Types (Act1, Act2, Op_Id, N);
2977 elsif Op_Name = Name_Op_Concat then
2978 Find_Concatenation_Types (Act1, Act2, Op_Id, N);
2980 -- Is this else null correct, or should it be an abort???
2986 -- Unary operator case
2989 if Op_Name = Name_Op_Subtract or else
2990 Op_Name = Name_Op_Add or else
2991 Op_Name = Name_Op_Abs
2993 Find_Unary_Types (Act1, Op_Id, N);
2996 Op_Name = Name_Op_Not
2998 Find_Negation_Types (Act1, Op_Id, N);
3000 -- Is this else null correct, or should it be an abort???
3006 end Analyze_Operator_Call;
3008 -------------------------------------------
3009 -- Analyze_Overloaded_Selected_Component --
3010 -------------------------------------------
3012 procedure Analyze_Overloaded_Selected_Component (N : Node_Id) is
3013 Nam : constant Node_Id := Prefix (N);
3014 Sel : constant Node_Id := Selector_Name (N);
3021 Set_Etype (Sel, Any_Type);
3023 Get_First_Interp (Nam, I, It);
3024 while Present (It.Typ) loop
3025 if Is_Access_Type (It.Typ) then
3026 T := Designated_Type (It.Typ);
3027 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3032 if Is_Record_Type (T) then
3034 -- If the prefix is a class-wide type, the visible components are
3035 -- those of the base type.
3037 if Is_Class_Wide_Type (T) then
3041 Comp := First_Entity (T);
3042 while Present (Comp) loop
3043 if Chars (Comp) = Chars (Sel)
3044 and then Is_Visible_Component (Comp)
3047 -- AI05-105: if the context is an object renaming with
3048 -- an anonymous access type, the expected type of the
3049 -- object must be anonymous. This is a name resolution rule.
3051 if Nkind (Parent (N)) /= N_Object_Renaming_Declaration
3052 or else No (Access_Definition (Parent (N)))
3053 or else Ekind (Etype (Comp)) = E_Anonymous_Access_Type
3055 Ekind (Etype (Comp)) = E_Anonymous_Access_Subprogram_Type
3057 Set_Entity (Sel, Comp);
3058 Set_Etype (Sel, Etype (Comp));
3059 Add_One_Interp (N, Etype (Comp), Etype (Comp));
3061 -- This also specifies a candidate to resolve the name.
3062 -- Further overloading will be resolved from context.
3063 -- The selector name itself does not carry overloading
3066 Set_Etype (Nam, It.Typ);
3069 -- Named access type in the context of a renaming
3070 -- declaration with an access definition. Remove
3071 -- inapplicable candidate.
3080 elsif Is_Concurrent_Type (T) then
3081 Comp := First_Entity (T);
3082 while Present (Comp)
3083 and then Comp /= First_Private_Entity (T)
3085 if Chars (Comp) = Chars (Sel) then
3086 if Is_Overloadable (Comp) then
3087 Add_One_Interp (Sel, Comp, Etype (Comp));
3089 Set_Entity_With_Style_Check (Sel, Comp);
3090 Generate_Reference (Comp, Sel);
3093 Set_Etype (Sel, Etype (Comp));
3094 Set_Etype (N, Etype (Comp));
3095 Set_Etype (Nam, It.Typ);
3097 -- For access type case, introduce explicit dereference for
3098 -- more uniform treatment of entry calls. Do this only once
3099 -- if several interpretations yield an access type.
3101 if Is_Access_Type (Etype (Nam))
3102 and then Nkind (Nam) /= N_Explicit_Dereference
3104 Insert_Explicit_Dereference (Nam);
3106 (Warn_On_Dereference, "?implicit dereference", N);
3113 Set_Is_Overloaded (N, Is_Overloaded (Sel));
3116 Get_Next_Interp (I, It);
3119 if Etype (N) = Any_Type
3120 and then not Try_Object_Operation (N)
3122 Error_Msg_NE ("undefined selector& for overloaded prefix", N, Sel);
3123 Set_Entity (Sel, Any_Id);
3124 Set_Etype (Sel, Any_Type);
3126 end Analyze_Overloaded_Selected_Component;
3128 ----------------------------------
3129 -- Analyze_Qualified_Expression --
3130 ----------------------------------
3132 procedure Analyze_Qualified_Expression (N : Node_Id) is
3133 Mark : constant Entity_Id := Subtype_Mark (N);
3134 Expr : constant Node_Id := Expression (N);
3140 Analyze_Expression (Expr);
3142 Set_Etype (N, Any_Type);
3147 if T = Any_Type then
3151 Check_Fully_Declared (T, N);
3153 -- If expected type is class-wide, check for exact match before
3154 -- expansion, because if the expression is a dispatching call it
3155 -- may be rewritten as explicit dereference with class-wide result.
3156 -- If expression is overloaded, retain only interpretations that
3157 -- will yield exact matches.
3159 if Is_Class_Wide_Type (T) then
3160 if not Is_Overloaded (Expr) then
3161 if Base_Type (Etype (Expr)) /= Base_Type (T) then
3162 if Nkind (Expr) = N_Aggregate then
3163 Error_Msg_N ("type of aggregate cannot be class-wide", Expr);
3165 Wrong_Type (Expr, T);
3170 Get_First_Interp (Expr, I, It);
3172 while Present (It.Nam) loop
3173 if Base_Type (It.Typ) /= Base_Type (T) then
3177 Get_Next_Interp (I, It);
3183 end Analyze_Qualified_Expression;
3185 -----------------------------------
3186 -- Analyze_Quantified_Expression --
3187 -----------------------------------
3189 procedure Analyze_Quantified_Expression (N : Node_Id) is
3190 Loc : constant Source_Ptr := Sloc (N);
3191 Ent : constant Entity_Id :=
3193 (E_Loop, Current_Scope, Sloc (N), 'L');
3198 Set_Etype (Ent, Standard_Void_Type);
3199 Set_Parent (Ent, N);
3201 if Present (Loop_Parameter_Specification (N)) then
3203 Make_Iteration_Scheme (Loc,
3204 Loop_Parameter_Specification =>
3205 Loop_Parameter_Specification (N));
3208 Make_Iteration_Scheme (Loc,
3209 Iterator_Specification =>
3210 Iterator_Specification (N));
3214 Set_Parent (Iterator, N);
3215 Analyze_Iteration_Scheme (Iterator);
3217 -- The loop specification may have been converted into an
3218 -- iterator specification during its analysis. Update the
3219 -- quantified node accordingly.
3221 if Present (Iterator_Specification (Iterator)) then
3222 Set_Iterator_Specification
3223 (N, Iterator_Specification (Iterator));
3224 Set_Loop_Parameter_Specification (N, Empty);
3227 Analyze (Condition (N));
3230 Set_Etype (N, Standard_Boolean);
3231 end Analyze_Quantified_Expression;
3237 procedure Analyze_Range (N : Node_Id) is
3238 L : constant Node_Id := Low_Bound (N);
3239 H : constant Node_Id := High_Bound (N);
3240 I1, I2 : Interp_Index;
3243 procedure Check_Common_Type (T1, T2 : Entity_Id);
3244 -- Verify the compatibility of two types, and choose the
3245 -- non universal one if the other is universal.
3247 procedure Check_High_Bound (T : Entity_Id);
3248 -- Test one interpretation of the low bound against all those
3249 -- of the high bound.
3251 procedure Check_Universal_Expression (N : Node_Id);
3252 -- In Ada83, reject bounds of a universal range that are not
3253 -- literals or entity names.
3255 -----------------------
3256 -- Check_Common_Type --
3257 -----------------------
3259 procedure Check_Common_Type (T1, T2 : Entity_Id) is
3261 if Covers (T1 => T1, T2 => T2)
3263 Covers (T1 => T2, T2 => T1)
3265 if T1 = Universal_Integer
3266 or else T1 = Universal_Real
3267 or else T1 = Any_Character
3269 Add_One_Interp (N, Base_Type (T2), Base_Type (T2));
3272 Add_One_Interp (N, T1, T1);
3275 Add_One_Interp (N, Base_Type (T1), Base_Type (T1));
3278 end Check_Common_Type;
3280 ----------------------
3281 -- Check_High_Bound --
3282 ----------------------
3284 procedure Check_High_Bound (T : Entity_Id) is
3286 if not Is_Overloaded (H) then
3287 Check_Common_Type (T, Etype (H));
3289 Get_First_Interp (H, I2, It2);
3290 while Present (It2.Typ) loop
3291 Check_Common_Type (T, It2.Typ);
3292 Get_Next_Interp (I2, It2);
3295 end Check_High_Bound;
3297 -----------------------------
3298 -- Is_Universal_Expression --
3299 -----------------------------
3301 procedure Check_Universal_Expression (N : Node_Id) is
3303 if Etype (N) = Universal_Integer
3304 and then Nkind (N) /= N_Integer_Literal
3305 and then not Is_Entity_Name (N)
3306 and then Nkind (N) /= N_Attribute_Reference
3308 Error_Msg_N ("illegal bound in discrete range", N);
3310 end Check_Universal_Expression;
3312 -- Start of processing for Analyze_Range
3315 Set_Etype (N, Any_Type);
3316 Analyze_Expression (L);
3317 Analyze_Expression (H);
3319 if Etype (L) = Any_Type or else Etype (H) = Any_Type then
3323 if not Is_Overloaded (L) then
3324 Check_High_Bound (Etype (L));
3326 Get_First_Interp (L, I1, It1);
3327 while Present (It1.Typ) loop
3328 Check_High_Bound (It1.Typ);
3329 Get_Next_Interp (I1, It1);
3333 -- If result is Any_Type, then we did not find a compatible pair
3335 if Etype (N) = Any_Type then
3336 Error_Msg_N ("incompatible types in range ", N);
3340 if Ada_Version = Ada_83
3342 (Nkind (Parent (N)) = N_Loop_Parameter_Specification
3343 or else Nkind (Parent (N)) = N_Constrained_Array_Definition)
3345 Check_Universal_Expression (L);
3346 Check_Universal_Expression (H);
3350 -----------------------
3351 -- Analyze_Reference --
3352 -----------------------
3354 procedure Analyze_Reference (N : Node_Id) is
3355 P : constant Node_Id := Prefix (N);
3358 Acc_Type : Entity_Id;
3363 -- An interesting error check, if we take the 'Reference of an object
3364 -- for which a pragma Atomic or Volatile has been given, and the type
3365 -- of the object is not Atomic or Volatile, then we are in trouble. The
3366 -- problem is that no trace of the atomic/volatile status will remain
3367 -- for the backend to respect when it deals with the resulting pointer,
3368 -- since the pointer type will not be marked atomic (it is a pointer to
3369 -- the base type of the object).
3371 -- It is not clear if that can ever occur, but in case it does, we will
3372 -- generate an error message. Not clear if this message can ever be
3373 -- generated, and pretty clear that it represents a bug if it is, still
3374 -- seems worth checking, except in CodePeer mode where we do not really
3375 -- care and don't want to bother the user.
3379 if Is_Entity_Name (P)
3380 and then Is_Object_Reference (P)
3381 and then not CodePeer_Mode
3386 if (Has_Atomic_Components (E)
3387 and then not Has_Atomic_Components (T))
3389 (Has_Volatile_Components (E)
3390 and then not Has_Volatile_Components (T))
3391 or else (Is_Atomic (E) and then not Is_Atomic (T))
3392 or else (Is_Volatile (E) and then not Is_Volatile (T))
3394 Error_Msg_N ("cannot take reference to Atomic/Volatile object", N);
3398 -- Carry on with normal processing
3400 Acc_Type := Create_Itype (E_Allocator_Type, N);
3401 Set_Etype (Acc_Type, Acc_Type);
3402 Set_Directly_Designated_Type (Acc_Type, Etype (P));
3403 Set_Etype (N, Acc_Type);
3404 end Analyze_Reference;
3406 --------------------------------
3407 -- Analyze_Selected_Component --
3408 --------------------------------
3410 -- Prefix is a record type or a task or protected type. In the latter case,
3411 -- the selector must denote a visible entry.
3413 procedure Analyze_Selected_Component (N : Node_Id) is
3414 Name : constant Node_Id := Prefix (N);
3415 Sel : constant Node_Id := Selector_Name (N);
3418 Has_Candidate : Boolean := False;
3421 Pent : Entity_Id := Empty;
3422 Prefix_Type : Entity_Id;
3424 Type_To_Use : Entity_Id;
3425 -- In most cases this is the Prefix_Type, but if the Prefix_Type is
3426 -- a class-wide type, we use its root type, whose components are
3427 -- present in the class-wide type.
3429 Is_Single_Concurrent_Object : Boolean;
3430 -- Set True if the prefix is a single task or a single protected object
3432 procedure Find_Component_In_Instance (Rec : Entity_Id);
3433 -- In an instance, a component of a private extension may not be visible
3434 -- while it was visible in the generic. Search candidate scope for a
3435 -- component with the proper identifier. This is only done if all other
3436 -- searches have failed. When the match is found (it always will be),
3437 -- the Etype of both N and Sel are set from this component, and the
3438 -- entity of Sel is set to reference this component.
3440 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean;
3441 -- It is known that the parent of N denotes a subprogram call. Comp
3442 -- is an overloadable component of the concurrent type of the prefix.
3443 -- Determine whether all formals of the parent of N and Comp are mode
3444 -- conformant. If the parent node is not analyzed yet it may be an
3445 -- indexed component rather than a function call.
3447 --------------------------------
3448 -- Find_Component_In_Instance --
3449 --------------------------------
3451 procedure Find_Component_In_Instance (Rec : Entity_Id) is
3455 Comp := First_Component (Rec);
3456 while Present (Comp) loop
3457 if Chars (Comp) = Chars (Sel) then
3458 Set_Entity_With_Style_Check (Sel, Comp);
3459 Set_Etype (Sel, Etype (Comp));
3460 Set_Etype (N, Etype (Comp));
3464 Next_Component (Comp);
3467 -- This must succeed because code was legal in the generic
3469 raise Program_Error;
3470 end Find_Component_In_Instance;
3472 ------------------------------
3473 -- Has_Mode_Conformant_Spec --
3474 ------------------------------
3476 function Has_Mode_Conformant_Spec (Comp : Entity_Id) return Boolean is
3477 Comp_Param : Entity_Id;
3479 Param_Typ : Entity_Id;
3482 Comp_Param := First_Formal (Comp);
3484 if Nkind (Parent (N)) = N_Indexed_Component then
3485 Param := First (Expressions (Parent (N)));
3487 Param := First (Parameter_Associations (Parent (N)));
3490 while Present (Comp_Param)
3491 and then Present (Param)
3493 Param_Typ := Find_Parameter_Type (Param);
3495 if Present (Param_Typ)
3497 not Conforming_Types
3498 (Etype (Comp_Param), Param_Typ, Mode_Conformant)
3503 Next_Formal (Comp_Param);
3507 -- One of the specs has additional formals
3509 if Present (Comp_Param) or else Present (Param) then
3514 end Has_Mode_Conformant_Spec;
3516 -- Start of processing for Analyze_Selected_Component
3519 Set_Etype (N, Any_Type);
3521 if Is_Overloaded (Name) then
3522 Analyze_Overloaded_Selected_Component (N);
3525 elsif Etype (Name) = Any_Type then
3526 Set_Entity (Sel, Any_Id);
3527 Set_Etype (Sel, Any_Type);
3531 Prefix_Type := Etype (Name);
3534 if Is_Access_Type (Prefix_Type) then
3536 -- A RACW object can never be used as prefix of a selected component
3537 -- since that means it is dereferenced without being a controlling
3538 -- operand of a dispatching operation (RM E.2.2(16/1)). Before
3539 -- reporting an error, we must check whether this is actually a
3540 -- dispatching call in prefix form.
3542 if Is_Remote_Access_To_Class_Wide_Type (Prefix_Type)
3543 and then Comes_From_Source (N)
3545 if Try_Object_Operation (N) then
3549 ("invalid dereference of a remote access-to-class-wide value",
3553 -- Normal case of selected component applied to access type
3556 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3558 if Is_Entity_Name (Name) then
3559 Pent := Entity (Name);
3560 elsif Nkind (Name) = N_Selected_Component
3561 and then Is_Entity_Name (Selector_Name (Name))
3563 Pent := Entity (Selector_Name (Name));
3566 Prefix_Type := Process_Implicit_Dereference_Prefix (Pent, Name);
3569 -- If we have an explicit dereference of a remote access-to-class-wide
3570 -- value, then issue an error (see RM-E.2.2(16/1)). However we first
3571 -- have to check for the case of a prefix that is a controlling operand
3572 -- of a prefixed dispatching call, as the dereference is legal in that
3573 -- case. Normally this condition is checked in Validate_Remote_Access_
3574 -- To_Class_Wide_Type, but we have to defer the checking for selected
3575 -- component prefixes because of the prefixed dispatching call case.
3576 -- Note that implicit dereferences are checked for this just above.
3578 elsif Nkind (Name) = N_Explicit_Dereference
3579 and then Is_Remote_Access_To_Class_Wide_Type (Etype (Prefix (Name)))
3580 and then Comes_From_Source (N)
3582 if Try_Object_Operation (N) then
3586 ("invalid dereference of a remote access-to-class-wide value",
3591 -- (Ada 2005): if the prefix is the limited view of a type, and
3592 -- the context already includes the full view, use the full view
3593 -- in what follows, either to retrieve a component of to find
3594 -- a primitive operation. If the prefix is an explicit dereference,
3595 -- set the type of the prefix to reflect this transformation.
3596 -- If the non-limited view is itself an incomplete type, get the
3597 -- full view if available.
3599 if Is_Incomplete_Type (Prefix_Type)
3600 and then From_With_Type (Prefix_Type)
3601 and then Present (Non_Limited_View (Prefix_Type))
3603 Prefix_Type := Get_Full_View (Non_Limited_View (Prefix_Type));
3605 if Nkind (N) = N_Explicit_Dereference then
3606 Set_Etype (Prefix (N), Prefix_Type);
3609 elsif Ekind (Prefix_Type) = E_Class_Wide_Type
3610 and then From_With_Type (Prefix_Type)
3611 and then Present (Non_Limited_View (Etype (Prefix_Type)))
3614 Class_Wide_Type (Non_Limited_View (Etype (Prefix_Type)));
3616 if Nkind (N) = N_Explicit_Dereference then
3617 Set_Etype (Prefix (N), Prefix_Type);
3621 if Ekind (Prefix_Type) = E_Private_Subtype then
3622 Prefix_Type := Base_Type (Prefix_Type);
3625 Type_To_Use := Prefix_Type;
3627 -- For class-wide types, use the entity list of the root type. This
3628 -- indirection is specially important for private extensions because
3629 -- only the root type get switched (not the class-wide type).
3631 if Is_Class_Wide_Type (Prefix_Type) then
3632 Type_To_Use := Root_Type (Prefix_Type);
3635 -- If the prefix is a single concurrent object, use its name in error
3636 -- messages, rather than that of its anonymous type.
3638 Is_Single_Concurrent_Object :=
3639 Is_Concurrent_Type (Prefix_Type)
3640 and then Is_Internal_Name (Chars (Prefix_Type))
3641 and then not Is_Derived_Type (Prefix_Type)
3642 and then Is_Entity_Name (Name);
3644 Comp := First_Entity (Type_To_Use);
3646 -- If the selector has an original discriminant, the node appears in
3647 -- an instance. Replace the discriminant with the corresponding one
3648 -- in the current discriminated type. For nested generics, this must
3649 -- be done transitively, so note the new original discriminant.
3651 if Nkind (Sel) = N_Identifier
3652 and then Present (Original_Discriminant (Sel))
3654 Comp := Find_Corresponding_Discriminant (Sel, Prefix_Type);
3656 -- Mark entity before rewriting, for completeness and because
3657 -- subsequent semantic checks might examine the original node.
3659 Set_Entity (Sel, Comp);
3660 Rewrite (Selector_Name (N),
3661 New_Occurrence_Of (Comp, Sloc (N)));
3662 Set_Original_Discriminant (Selector_Name (N), Comp);
3663 Set_Etype (N, Etype (Comp));
3665 if Is_Access_Type (Etype (Name)) then
3666 Insert_Explicit_Dereference (Name);
3667 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
3670 elsif Is_Record_Type (Prefix_Type) then
3672 -- Find component with given name
3674 while Present (Comp) loop
3675 if Chars (Comp) = Chars (Sel)
3676 and then Is_Visible_Component (Comp)
3678 Set_Entity_With_Style_Check (Sel, Comp);
3679 Set_Etype (Sel, Etype (Comp));
3681 if Ekind (Comp) = E_Discriminant then
3682 if Is_Unchecked_Union (Base_Type (Prefix_Type)) then
3684 ("cannot reference discriminant of Unchecked_Union",
3688 if Is_Generic_Type (Prefix_Type)
3690 Is_Generic_Type (Root_Type (Prefix_Type))
3692 Set_Original_Discriminant (Sel, Comp);
3696 -- Resolve the prefix early otherwise it is not possible to
3697 -- build the actual subtype of the component: it may need
3698 -- to duplicate this prefix and duplication is only allowed
3699 -- on fully resolved expressions.
3703 -- Ada 2005 (AI-50217): Check wrong use of incomplete types or
3704 -- subtypes in a package specification.
3707 -- limited with Pkg;
3709 -- type Acc_Inc is access Pkg.T;
3711 -- N : Natural := X.all.Comp; -- ERROR, limited view
3712 -- end Pkg; -- Comp is not visible
3714 if Nkind (Name) = N_Explicit_Dereference
3715 and then From_With_Type (Etype (Prefix (Name)))
3716 and then not Is_Potentially_Use_Visible (Etype (Name))
3717 and then Nkind (Parent (Cunit_Entity (Current_Sem_Unit))) =
3718 N_Package_Specification
3721 ("premature usage of incomplete}", Prefix (Name),
3722 Etype (Prefix (Name)));
3725 -- We never need an actual subtype for the case of a selection
3726 -- for a indexed component of a non-packed array, since in
3727 -- this case gigi generates all the checks and can find the
3728 -- necessary bounds information.
3730 -- We also do not need an actual subtype for the case of a
3731 -- first, last, length, or range attribute applied to a
3732 -- non-packed array, since gigi can again get the bounds in
3733 -- these cases (gigi cannot handle the packed case, since it
3734 -- has the bounds of the packed array type, not the original
3735 -- bounds of the type). However, if the prefix is itself a
3736 -- selected component, as in a.b.c (i), gigi may regard a.b.c
3737 -- as a dynamic-sized temporary, so we do generate an actual
3738 -- subtype for this case.
3740 Parent_N := Parent (N);
3742 if not Is_Packed (Etype (Comp))
3744 ((Nkind (Parent_N) = N_Indexed_Component
3745 and then Nkind (Name) /= N_Selected_Component)
3747 (Nkind (Parent_N) = N_Attribute_Reference
3748 and then (Attribute_Name (Parent_N) = Name_First
3750 Attribute_Name (Parent_N) = Name_Last
3752 Attribute_Name (Parent_N) = Name_Length
3754 Attribute_Name (Parent_N) = Name_Range)))
3756 Set_Etype (N, Etype (Comp));
3758 -- If full analysis is not enabled, we do not generate an
3759 -- actual subtype, because in the absence of expansion
3760 -- reference to a formal of a protected type, for example,
3761 -- will not be properly transformed, and will lead to
3762 -- out-of-scope references in gigi.
3764 -- In all other cases, we currently build an actual subtype.
3765 -- It seems likely that many of these cases can be avoided,
3766 -- but right now, the front end makes direct references to the
3767 -- bounds (e.g. in generating a length check), and if we do
3768 -- not make an actual subtype, we end up getting a direct
3769 -- reference to a discriminant, which will not do.
3771 elsif Full_Analysis then
3773 Build_Actual_Subtype_Of_Component (Etype (Comp), N);
3774 Insert_Action (N, Act_Decl);
3776 if No (Act_Decl) then
3777 Set_Etype (N, Etype (Comp));
3780 -- Component type depends on discriminants. Enter the
3781 -- main attributes of the subtype.
3784 Subt : constant Entity_Id :=
3785 Defining_Identifier (Act_Decl);
3788 Set_Etype (Subt, Base_Type (Etype (Comp)));
3789 Set_Ekind (Subt, Ekind (Etype (Comp)));
3790 Set_Etype (N, Subt);
3794 -- If Full_Analysis not enabled, just set the Etype
3797 Set_Etype (N, Etype (Comp));
3803 -- If the prefix is a private extension, check only the visible
3804 -- components of the partial view. This must include the tag,
3805 -- which can appear in expanded code in a tag check.
3807 if Ekind (Type_To_Use) = E_Record_Type_With_Private
3808 and then Chars (Selector_Name (N)) /= Name_uTag
3810 exit when Comp = Last_Entity (Type_To_Use);
3816 -- Ada 2005 (AI-252): The selected component can be interpreted as
3817 -- a prefixed view of a subprogram. Depending on the context, this is
3818 -- either a name that can appear in a renaming declaration, or part
3819 -- of an enclosing call given in prefix form.
3821 -- Ada 2005 (AI05-0030): In the case of dispatching requeue, the
3822 -- selected component should resolve to a name.
3824 if Ada_Version >= Ada_2005
3825 and then Is_Tagged_Type (Prefix_Type)
3826 and then not Is_Concurrent_Type (Prefix_Type)
3828 if Nkind (Parent (N)) = N_Generic_Association
3829 or else Nkind (Parent (N)) = N_Requeue_Statement
3830 or else Nkind (Parent (N)) = N_Subprogram_Renaming_Declaration
3832 if Find_Primitive_Operation (N) then
3836 elsif Try_Object_Operation (N) then
3840 -- If the transformation fails, it will be necessary to redo the
3841 -- analysis with all errors enabled, to indicate candidate
3842 -- interpretations and reasons for each failure ???
3846 elsif Is_Private_Type (Prefix_Type) then
3848 -- Allow access only to discriminants of the type. If the type has
3849 -- no full view, gigi uses the parent type for the components, so we
3850 -- do the same here.
3852 if No (Full_View (Prefix_Type)) then
3853 Type_To_Use := Root_Type (Base_Type (Prefix_Type));
3854 Comp := First_Entity (Type_To_Use);
3857 while Present (Comp) loop
3858 if Chars (Comp) = Chars (Sel) then
3859 if Ekind (Comp) = E_Discriminant then
3860 Set_Entity_With_Style_Check (Sel, Comp);
3861 Generate_Reference (Comp, Sel);
3863 Set_Etype (Sel, Etype (Comp));
3864 Set_Etype (N, Etype (Comp));
3866 if Is_Generic_Type (Prefix_Type)
3867 or else Is_Generic_Type (Root_Type (Prefix_Type))
3869 Set_Original_Discriminant (Sel, Comp);
3872 -- Before declaring an error, check whether this is tagged
3873 -- private type and a call to a primitive operation.
3875 elsif Ada_Version >= Ada_2005
3876 and then Is_Tagged_Type (Prefix_Type)
3877 and then Try_Object_Operation (N)
3882 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
3883 Error_Msg_NE ("invisible selector& for }", N, Sel);
3884 Set_Entity (Sel, Any_Id);
3885 Set_Etype (N, Any_Type);
3894 elsif Is_Concurrent_Type (Prefix_Type) then
3896 -- Find visible operation with given name. For a protected type,
3897 -- the possible candidates are discriminants, entries or protected
3898 -- procedures. For a task type, the set can only include entries or
3899 -- discriminants if the task type is not an enclosing scope. If it
3900 -- is an enclosing scope (e.g. in an inner task) then all entities
3901 -- are visible, but the prefix must denote the enclosing scope, i.e.
3902 -- can only be a direct name or an expanded name.
3904 Set_Etype (Sel, Any_Type);
3905 In_Scope := In_Open_Scopes (Prefix_Type);
3907 while Present (Comp) loop
3908 if Chars (Comp) = Chars (Sel) then
3909 if Is_Overloadable (Comp) then
3910 Add_One_Interp (Sel, Comp, Etype (Comp));
3912 -- If the prefix is tagged, the correct interpretation may
3913 -- lie in the primitive or class-wide operations of the
3914 -- type. Perform a simple conformance check to determine
3915 -- whether Try_Object_Operation should be invoked even if
3916 -- a visible entity is found.
3918 if Is_Tagged_Type (Prefix_Type)
3920 Nkind_In (Parent (N), N_Procedure_Call_Statement,
3922 N_Indexed_Component)
3923 and then Has_Mode_Conformant_Spec (Comp)
3925 Has_Candidate := True;
3928 -- Note: a selected component may not denote a component of a
3929 -- protected type (4.1.3(7)).
3931 elsif Ekind_In (Comp, E_Discriminant, E_Entry_Family)
3933 and then not Is_Protected_Type (Prefix_Type)
3934 and then Is_Entity_Name (Name))
3936 Set_Entity_With_Style_Check (Sel, Comp);
3937 Generate_Reference (Comp, Sel);
3943 Set_Etype (Sel, Etype (Comp));
3944 Set_Etype (N, Etype (Comp));
3946 if Ekind (Comp) = E_Discriminant then
3947 Set_Original_Discriminant (Sel, Comp);
3950 -- For access type case, introduce explicit dereference for
3951 -- more uniform treatment of entry calls.
3953 if Is_Access_Type (Etype (Name)) then
3954 Insert_Explicit_Dereference (Name);
3956 (Warn_On_Dereference, "?implicit dereference", N);
3962 exit when not In_Scope
3964 Comp = First_Private_Entity (Base_Type (Prefix_Type));
3967 -- If there is no visible entity with the given name or none of the
3968 -- visible entities are plausible interpretations, check whether
3969 -- there is some other primitive operation with that name.
3971 if Ada_Version >= Ada_2005
3972 and then Is_Tagged_Type (Prefix_Type)
3974 if (Etype (N) = Any_Type
3975 or else not Has_Candidate)
3976 and then Try_Object_Operation (N)
3980 -- If the context is not syntactically a procedure call, it
3981 -- may be a call to a primitive function declared outside of
3982 -- the synchronized type.
3984 -- If the context is a procedure call, there might still be
3985 -- an overloading between an entry and a primitive procedure
3986 -- declared outside of the synchronized type, called in prefix
3987 -- notation. This is harder to disambiguate because in one case
3988 -- the controlling formal is implicit ???
3990 elsif Nkind (Parent (N)) /= N_Procedure_Call_Statement
3991 and then Nkind (Parent (N)) /= N_Indexed_Component
3992 and then Try_Object_Operation (N)
3998 if Etype (N) = Any_Type and then Is_Protected_Type (Prefix_Type) then
3999 -- Case of a prefix of a protected type: selector might denote
4000 -- an invisible private component.
4002 Comp := First_Private_Entity (Base_Type (Prefix_Type));
4003 while Present (Comp) and then Chars (Comp) /= Chars (Sel) loop
4007 if Present (Comp) then
4008 if Is_Single_Concurrent_Object then
4009 Error_Msg_Node_2 := Entity (Name);
4010 Error_Msg_NE ("invisible selector& for &", N, Sel);
4013 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4014 Error_Msg_NE ("invisible selector& for }", N, Sel);
4020 Set_Is_Overloaded (N, Is_Overloaded (Sel));
4025 Error_Msg_NE ("invalid prefix in selected component&", N, Sel);
4028 -- If N still has no type, the component is not defined in the prefix
4030 if Etype (N) = Any_Type then
4032 if Is_Single_Concurrent_Object then
4033 Error_Msg_Node_2 := Entity (Name);
4034 Error_Msg_NE ("no selector& for&", N, Sel);
4036 Check_Misspelled_Selector (Type_To_Use, Sel);
4038 elsif Is_Generic_Type (Prefix_Type)
4039 and then Ekind (Prefix_Type) = E_Record_Type_With_Private
4040 and then Prefix_Type /= Etype (Prefix_Type)
4041 and then Is_Record_Type (Etype (Prefix_Type))
4043 -- If this is a derived formal type, the parent may have
4044 -- different visibility at this point. Try for an inherited
4045 -- component before reporting an error.
4047 Set_Etype (Prefix (N), Etype (Prefix_Type));
4048 Analyze_Selected_Component (N);
4051 -- Similarly, if this is the actual for a formal derived type, the
4052 -- component inherited from the generic parent may not be visible
4053 -- in the actual, but the selected component is legal.
4055 elsif Ekind (Prefix_Type) = E_Record_Subtype_With_Private
4056 and then Is_Generic_Actual_Type (Prefix_Type)
4057 and then Present (Full_View (Prefix_Type))
4060 Find_Component_In_Instance
4061 (Generic_Parent_Type (Parent (Prefix_Type)));
4064 -- Finally, the formal and the actual may be private extensions,
4065 -- but the generic is declared in a child unit of the parent, and
4066 -- an addtional step is needed to retrieve the proper scope.
4069 and then Present (Parent_Subtype (Etype (Base_Type (Prefix_Type))))
4071 Find_Component_In_Instance
4072 (Parent_Subtype (Etype (Base_Type (Prefix_Type))));
4075 -- Component not found, specialize error message when appropriate
4078 if Ekind (Prefix_Type) = E_Record_Subtype then
4080 -- Check whether this is a component of the base type which
4081 -- is absent from a statically constrained subtype. This will
4082 -- raise constraint error at run time, but is not a compile-
4083 -- time error. When the selector is illegal for base type as
4084 -- well fall through and generate a compilation error anyway.
4086 Comp := First_Component (Base_Type (Prefix_Type));
4087 while Present (Comp) loop
4088 if Chars (Comp) = Chars (Sel)
4089 and then Is_Visible_Component (Comp)
4091 Set_Entity_With_Style_Check (Sel, Comp);
4092 Generate_Reference (Comp, Sel);
4093 Set_Etype (Sel, Etype (Comp));
4094 Set_Etype (N, Etype (Comp));
4096 -- Emit appropriate message. Gigi will replace the
4097 -- node subsequently with the appropriate Raise.
4099 Apply_Compile_Time_Constraint_Error
4100 (N, "component not present in }?",
4101 CE_Discriminant_Check_Failed,
4102 Ent => Prefix_Type, Rep => False);
4103 Set_Raises_Constraint_Error (N);
4107 Next_Component (Comp);
4112 Error_Msg_Node_2 := First_Subtype (Prefix_Type);
4113 Error_Msg_NE ("no selector& for}", N, Sel);
4115 Check_Misspelled_Selector (Type_To_Use, Sel);
4118 Set_Entity (Sel, Any_Id);
4119 Set_Etype (Sel, Any_Type);
4121 end Analyze_Selected_Component;
4123 ---------------------------
4124 -- Analyze_Short_Circuit --
4125 ---------------------------
4127 procedure Analyze_Short_Circuit (N : Node_Id) is
4128 L : constant Node_Id := Left_Opnd (N);
4129 R : constant Node_Id := Right_Opnd (N);
4134 Analyze_Expression (L);
4135 Analyze_Expression (R);
4136 Set_Etype (N, Any_Type);
4138 if not Is_Overloaded (L) then
4139 if Root_Type (Etype (L)) = Standard_Boolean
4140 and then Has_Compatible_Type (R, Etype (L))
4142 Add_One_Interp (N, Etype (L), Etype (L));
4146 Get_First_Interp (L, Ind, It);
4147 while Present (It.Typ) loop
4148 if Root_Type (It.Typ) = Standard_Boolean
4149 and then Has_Compatible_Type (R, It.Typ)
4151 Add_One_Interp (N, It.Typ, It.Typ);
4154 Get_Next_Interp (Ind, It);
4158 -- Here we have failed to find an interpretation. Clearly we know that
4159 -- it is not the case that both operands can have an interpretation of
4160 -- Boolean, but this is by far the most likely intended interpretation.
4161 -- So we simply resolve both operands as Booleans, and at least one of
4162 -- these resolutions will generate an error message, and we do not need
4163 -- to give another error message on the short circuit operation itself.
4165 if Etype (N) = Any_Type then
4166 Resolve (L, Standard_Boolean);
4167 Resolve (R, Standard_Boolean);
4168 Set_Etype (N, Standard_Boolean);
4170 end Analyze_Short_Circuit;
4176 procedure Analyze_Slice (N : Node_Id) is
4177 P : constant Node_Id := Prefix (N);
4178 D : constant Node_Id := Discrete_Range (N);
4179 Array_Type : Entity_Id;
4181 procedure Analyze_Overloaded_Slice;
4182 -- If the prefix is overloaded, select those interpretations that
4183 -- yield a one-dimensional array type.
4185 ------------------------------
4186 -- Analyze_Overloaded_Slice --
4187 ------------------------------
4189 procedure Analyze_Overloaded_Slice is
4195 Set_Etype (N, Any_Type);
4197 Get_First_Interp (P, I, It);
4198 while Present (It.Nam) loop
4201 if Is_Access_Type (Typ) then
4202 Typ := Designated_Type (Typ);
4203 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4206 if Is_Array_Type (Typ)
4207 and then Number_Dimensions (Typ) = 1
4208 and then Has_Compatible_Type (D, Etype (First_Index (Typ)))
4210 Add_One_Interp (N, Typ, Typ);
4213 Get_Next_Interp (I, It);
4216 if Etype (N) = Any_Type then
4217 Error_Msg_N ("expect array type in prefix of slice", N);
4219 end Analyze_Overloaded_Slice;
4221 -- Start of processing for Analyze_Slice
4227 if Is_Overloaded (P) then
4228 Analyze_Overloaded_Slice;
4231 Array_Type := Etype (P);
4232 Set_Etype (N, Any_Type);
4234 if Is_Access_Type (Array_Type) then
4235 Array_Type := Designated_Type (Array_Type);
4236 Error_Msg_NW (Warn_On_Dereference, "?implicit dereference", N);
4239 if not Is_Array_Type (Array_Type) then
4240 Wrong_Type (P, Any_Array);
4242 elsif Number_Dimensions (Array_Type) > 1 then
4244 ("type is not one-dimensional array in slice prefix", N);
4247 Has_Compatible_Type (D, Etype (First_Index (Array_Type)))
4249 Wrong_Type (D, Etype (First_Index (Array_Type)));
4252 Set_Etype (N, Array_Type);
4257 -----------------------------
4258 -- Analyze_Type_Conversion --
4259 -----------------------------
4261 procedure Analyze_Type_Conversion (N : Node_Id) is
4262 Expr : constant Node_Id := Expression (N);
4266 -- If Conversion_OK is set, then the Etype is already set, and the
4267 -- only processing required is to analyze the expression. This is
4268 -- used to construct certain "illegal" conversions which are not
4269 -- allowed by Ada semantics, but can be handled OK by Gigi, see
4270 -- Sinfo for further details.
4272 if Conversion_OK (N) then
4277 -- Otherwise full type analysis is required, as well as some semantic
4278 -- checks to make sure the argument of the conversion is appropriate.
4280 Find_Type (Subtype_Mark (N));
4281 T := Entity (Subtype_Mark (N));
4283 Check_Fully_Declared (T, N);
4284 Analyze_Expression (Expr);
4285 Validate_Remote_Type_Type_Conversion (N);
4287 -- Only remaining step is validity checks on the argument. These
4288 -- are skipped if the conversion does not come from the source.
4290 if not Comes_From_Source (N) then
4293 -- If there was an error in a generic unit, no need to replicate the
4294 -- error message. Conversely, constant-folding in the generic may
4295 -- transform the argument of a conversion into a string literal, which
4296 -- is legal. Therefore the following tests are not performed in an
4299 elsif In_Instance then
4302 elsif Nkind (Expr) = N_Null then
4303 Error_Msg_N ("argument of conversion cannot be null", N);
4304 Error_Msg_N ("\use qualified expression instead", N);
4305 Set_Etype (N, Any_Type);
4307 elsif Nkind (Expr) = N_Aggregate then
4308 Error_Msg_N ("argument of conversion cannot be aggregate", N);
4309 Error_Msg_N ("\use qualified expression instead", N);
4311 elsif Nkind (Expr) = N_Allocator then
4312 Error_Msg_N ("argument of conversion cannot be an allocator", N);
4313 Error_Msg_N ("\use qualified expression instead", N);
4315 elsif Nkind (Expr) = N_String_Literal then
4316 Error_Msg_N ("argument of conversion cannot be string literal", N);
4317 Error_Msg_N ("\use qualified expression instead", N);
4319 elsif Nkind (Expr) = N_Character_Literal then
4320 if Ada_Version = Ada_83 then
4323 Error_Msg_N ("argument of conversion cannot be character literal",
4325 Error_Msg_N ("\use qualified expression instead", N);
4328 elsif Nkind (Expr) = N_Attribute_Reference
4330 (Attribute_Name (Expr) = Name_Access or else
4331 Attribute_Name (Expr) = Name_Unchecked_Access or else
4332 Attribute_Name (Expr) = Name_Unrestricted_Access)
4334 Error_Msg_N ("argument of conversion cannot be access", N);
4335 Error_Msg_N ("\use qualified expression instead", N);
4337 end Analyze_Type_Conversion;
4339 ----------------------
4340 -- Analyze_Unary_Op --
4341 ----------------------
4343 procedure Analyze_Unary_Op (N : Node_Id) is
4344 R : constant Node_Id := Right_Opnd (N);
4345 Op_Id : Entity_Id := Entity (N);
4348 Set_Etype (N, Any_Type);
4349 Candidate_Type := Empty;
4351 Analyze_Expression (R);
4353 if Present (Op_Id) then
4354 if Ekind (Op_Id) = E_Operator then
4355 Find_Unary_Types (R, Op_Id, N);
4357 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4361 Op_Id := Get_Name_Entity_Id (Chars (N));
4362 while Present (Op_Id) loop
4363 if Ekind (Op_Id) = E_Operator then
4364 if No (Next_Entity (First_Entity (Op_Id))) then
4365 Find_Unary_Types (R, Op_Id, N);
4368 elsif Is_Overloadable (Op_Id) then
4369 Analyze_User_Defined_Unary_Op (N, Op_Id);
4372 Op_Id := Homonym (Op_Id);
4377 end Analyze_Unary_Op;
4379 ----------------------------------
4380 -- Analyze_Unchecked_Expression --
4381 ----------------------------------
4383 procedure Analyze_Unchecked_Expression (N : Node_Id) is
4385 Analyze (Expression (N), Suppress => All_Checks);
4386 Set_Etype (N, Etype (Expression (N)));
4387 Save_Interps (Expression (N), N);
4388 end Analyze_Unchecked_Expression;
4390 ---------------------------------------
4391 -- Analyze_Unchecked_Type_Conversion --
4392 ---------------------------------------
4394 procedure Analyze_Unchecked_Type_Conversion (N : Node_Id) is
4396 Find_Type (Subtype_Mark (N));
4397 Analyze_Expression (Expression (N));
4398 Set_Etype (N, Entity (Subtype_Mark (N)));
4399 end Analyze_Unchecked_Type_Conversion;
4401 ------------------------------------
4402 -- Analyze_User_Defined_Binary_Op --
4403 ------------------------------------
4405 procedure Analyze_User_Defined_Binary_Op
4410 -- Only do analysis if the operator Comes_From_Source, since otherwise
4411 -- the operator was generated by the expander, and all such operators
4412 -- always refer to the operators in package Standard.
4414 if Comes_From_Source (N) then
4416 F1 : constant Entity_Id := First_Formal (Op_Id);
4417 F2 : constant Entity_Id := Next_Formal (F1);
4420 -- Verify that Op_Id is a visible binary function. Note that since
4421 -- we know Op_Id is overloaded, potentially use visible means use
4422 -- visible for sure (RM 9.4(11)).
4424 if Ekind (Op_Id) = E_Function
4425 and then Present (F2)
4426 and then (Is_Immediately_Visible (Op_Id)
4427 or else Is_Potentially_Use_Visible (Op_Id))
4428 and then Has_Compatible_Type (Left_Opnd (N), Etype (F1))
4429 and then Has_Compatible_Type (Right_Opnd (N), Etype (F2))
4431 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4433 -- If the left operand is overloaded, indicate that the
4434 -- current type is a viable candidate. This is redundant
4435 -- in most cases, but for equality and comparison operators
4436 -- where the context does not impose a type on the operands,
4437 -- setting the proper type is necessary to avoid subsequent
4438 -- ambiguities during resolution, when both user-defined and
4439 -- predefined operators may be candidates.
4441 if Is_Overloaded (Left_Opnd (N)) then
4442 Set_Etype (Left_Opnd (N), Etype (F1));
4445 if Debug_Flag_E then
4446 Write_Str ("user defined operator ");
4447 Write_Name (Chars (Op_Id));
4448 Write_Str (" on node ");
4449 Write_Int (Int (N));
4455 end Analyze_User_Defined_Binary_Op;
4457 -----------------------------------
4458 -- Analyze_User_Defined_Unary_Op --
4459 -----------------------------------
4461 procedure Analyze_User_Defined_Unary_Op
4466 -- Only do analysis if the operator Comes_From_Source, since otherwise
4467 -- the operator was generated by the expander, and all such operators
4468 -- always refer to the operators in package Standard.
4470 if Comes_From_Source (N) then
4472 F : constant Entity_Id := First_Formal (Op_Id);
4475 -- Verify that Op_Id is a visible unary function. Note that since
4476 -- we know Op_Id is overloaded, potentially use visible means use
4477 -- visible for sure (RM 9.4(11)).
4479 if Ekind (Op_Id) = E_Function
4480 and then No (Next_Formal (F))
4481 and then (Is_Immediately_Visible (Op_Id)
4482 or else Is_Potentially_Use_Visible (Op_Id))
4483 and then Has_Compatible_Type (Right_Opnd (N), Etype (F))
4485 Add_One_Interp (N, Op_Id, Etype (Op_Id));
4489 end Analyze_User_Defined_Unary_Op;
4491 ---------------------------
4492 -- Check_Arithmetic_Pair --
4493 ---------------------------
4495 procedure Check_Arithmetic_Pair
4496 (T1, T2 : Entity_Id;
4500 Op_Name : constant Name_Id := Chars (Op_Id);
4502 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean;
4503 -- Check whether the fixed-point type Typ has a user-defined operator
4504 -- (multiplication or division) that should hide the corresponding
4505 -- predefined operator. Used to implement Ada 2005 AI-264, to make
4506 -- such operators more visible and therefore useful.
4508 -- If the name of the operation is an expanded name with prefix
4509 -- Standard, the predefined universal fixed operator is available,
4510 -- as specified by AI-420 (RM 4.5.5 (19.1/2)).
4512 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id;
4513 -- Get specific type (i.e. non-universal type if there is one)
4519 function Has_Fixed_Op (Typ : Entity_Id; Op : Entity_Id) return Boolean is
4520 Bas : constant Entity_Id := Base_Type (Typ);
4526 -- If the universal_fixed operation is given explicitly the rule
4527 -- concerning primitive operations of the type do not apply.
4529 if Nkind (N) = N_Function_Call
4530 and then Nkind (Name (N)) = N_Expanded_Name
4531 and then Entity (Prefix (Name (N))) = Standard_Standard
4536 -- The operation is treated as primitive if it is declared in the
4537 -- same scope as the type, and therefore on the same entity chain.
4539 Ent := Next_Entity (Typ);
4540 while Present (Ent) loop
4541 if Chars (Ent) = Chars (Op) then
4542 F1 := First_Formal (Ent);
4543 F2 := Next_Formal (F1);
4545 -- The operation counts as primitive if either operand or
4546 -- result are of the given base type, and both operands are
4547 -- fixed point types.
4549 if (Base_Type (Etype (F1)) = Bas
4550 and then Is_Fixed_Point_Type (Etype (F2)))
4553 (Base_Type (Etype (F2)) = Bas
4554 and then Is_Fixed_Point_Type (Etype (F1)))
4557 (Base_Type (Etype (Ent)) = Bas
4558 and then Is_Fixed_Point_Type (Etype (F1))
4559 and then Is_Fixed_Point_Type (Etype (F2)))
4575 function Specific_Type (T1, T2 : Entity_Id) return Entity_Id is
4577 if T1 = Universal_Integer or else T1 = Universal_Real then
4578 return Base_Type (T2);
4580 return Base_Type (T1);
4584 -- Start of processing for Check_Arithmetic_Pair
4587 if Op_Name = Name_Op_Add or else Op_Name = Name_Op_Subtract then
4589 if Is_Numeric_Type (T1)
4590 and then Is_Numeric_Type (T2)
4591 and then (Covers (T1 => T1, T2 => T2)
4593 Covers (T1 => T2, T2 => T1))
4595 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4598 elsif Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide then
4600 if Is_Fixed_Point_Type (T1)
4601 and then (Is_Fixed_Point_Type (T2)
4602 or else T2 = Universal_Real)
4604 -- If Treat_Fixed_As_Integer is set then the Etype is already set
4605 -- and no further processing is required (this is the case of an
4606 -- operator constructed by Exp_Fixd for a fixed point operation)
4607 -- Otherwise add one interpretation with universal fixed result
4608 -- If the operator is given in functional notation, it comes
4609 -- from source and Fixed_As_Integer cannot apply.
4611 if (Nkind (N) not in N_Op
4612 or else not Treat_Fixed_As_Integer (N))
4614 (not Has_Fixed_Op (T1, Op_Id)
4615 or else Nkind (Parent (N)) = N_Type_Conversion)
4617 Add_One_Interp (N, Op_Id, Universal_Fixed);
4620 elsif Is_Fixed_Point_Type (T2)
4621 and then (Nkind (N) not in N_Op
4622 or else not Treat_Fixed_As_Integer (N))
4623 and then T1 = Universal_Real
4625 (not Has_Fixed_Op (T1, Op_Id)
4626 or else Nkind (Parent (N)) = N_Type_Conversion)
4628 Add_One_Interp (N, Op_Id, Universal_Fixed);
4630 elsif Is_Numeric_Type (T1)
4631 and then Is_Numeric_Type (T2)
4632 and then (Covers (T1 => T1, T2 => T2)
4634 Covers (T1 => T2, T2 => T1))
4636 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4638 elsif Is_Fixed_Point_Type (T1)
4639 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4640 or else T2 = Universal_Integer)
4642 Add_One_Interp (N, Op_Id, T1);
4644 elsif T2 = Universal_Real
4645 and then Base_Type (T1) = Base_Type (Standard_Integer)
4646 and then Op_Name = Name_Op_Multiply
4648 Add_One_Interp (N, Op_Id, Any_Fixed);
4650 elsif T1 = Universal_Real
4651 and then Base_Type (T2) = Base_Type (Standard_Integer)
4653 Add_One_Interp (N, Op_Id, Any_Fixed);
4655 elsif Is_Fixed_Point_Type (T2)
4656 and then (Base_Type (T1) = Base_Type (Standard_Integer)
4657 or else T1 = Universal_Integer)
4658 and then Op_Name = Name_Op_Multiply
4660 Add_One_Interp (N, Op_Id, T2);
4662 elsif T1 = Universal_Real and then T2 = Universal_Integer then
4663 Add_One_Interp (N, Op_Id, T1);
4665 elsif T2 = Universal_Real
4666 and then T1 = Universal_Integer
4667 and then Op_Name = Name_Op_Multiply
4669 Add_One_Interp (N, Op_Id, T2);
4672 elsif Op_Name = Name_Op_Mod or else Op_Name = Name_Op_Rem then
4674 -- Note: The fixed-point operands case with Treat_Fixed_As_Integer
4675 -- set does not require any special processing, since the Etype is
4676 -- already set (case of operation constructed by Exp_Fixed).
4678 if Is_Integer_Type (T1)
4679 and then (Covers (T1 => T1, T2 => T2)
4681 Covers (T1 => T2, T2 => T1))
4683 Add_One_Interp (N, Op_Id, Specific_Type (T1, T2));
4686 elsif Op_Name = Name_Op_Expon then
4687 if Is_Numeric_Type (T1)
4688 and then not Is_Fixed_Point_Type (T1)
4689 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4690 or else T2 = Universal_Integer)
4692 Add_One_Interp (N, Op_Id, Base_Type (T1));
4695 else pragma Assert (Nkind (N) in N_Op_Shift);
4697 -- If not one of the predefined operators, the node may be one
4698 -- of the intrinsic functions. Its kind is always specific, and
4699 -- we can use it directly, rather than the name of the operation.
4701 if Is_Integer_Type (T1)
4702 and then (Base_Type (T2) = Base_Type (Standard_Integer)
4703 or else T2 = Universal_Integer)
4705 Add_One_Interp (N, Op_Id, Base_Type (T1));
4708 end Check_Arithmetic_Pair;
4710 -------------------------------
4711 -- Check_Misspelled_Selector --
4712 -------------------------------
4714 procedure Check_Misspelled_Selector
4715 (Prefix : Entity_Id;
4718 Max_Suggestions : constant := 2;
4719 Nr_Of_Suggestions : Natural := 0;
4721 Suggestion_1 : Entity_Id := Empty;
4722 Suggestion_2 : Entity_Id := Empty;
4727 -- All the components of the prefix of selector Sel are matched
4728 -- against Sel and a count is maintained of possible misspellings.
4729 -- When at the end of the analysis there are one or two (not more!)
4730 -- possible misspellings, these misspellings will be suggested as
4731 -- possible correction.
4733 if not (Is_Private_Type (Prefix) or else Is_Record_Type (Prefix)) then
4735 -- Concurrent types should be handled as well ???
4740 Comp := First_Entity (Prefix);
4741 while Nr_Of_Suggestions <= Max_Suggestions and then Present (Comp) loop
4742 if Is_Visible_Component (Comp) then
4743 if Is_Bad_Spelling_Of (Chars (Comp), Chars (Sel)) then
4744 Nr_Of_Suggestions := Nr_Of_Suggestions + 1;
4746 case Nr_Of_Suggestions is
4747 when 1 => Suggestion_1 := Comp;
4748 when 2 => Suggestion_2 := Comp;
4749 when others => exit;
4754 Comp := Next_Entity (Comp);
4757 -- Report at most two suggestions
4759 if Nr_Of_Suggestions = 1 then
4760 Error_Msg_NE -- CODEFIX
4761 ("\possible misspelling of&", Sel, Suggestion_1);
4763 elsif Nr_Of_Suggestions = 2 then
4764 Error_Msg_Node_2 := Suggestion_2;
4765 Error_Msg_NE -- CODEFIX
4766 ("\possible misspelling of& or&", Sel, Suggestion_1);
4768 end Check_Misspelled_Selector;
4770 ----------------------
4771 -- Defined_In_Scope --
4772 ----------------------
4774 function Defined_In_Scope (T : Entity_Id; S : Entity_Id) return Boolean
4776 S1 : constant Entity_Id := Scope (Base_Type (T));
4779 or else (S1 = System_Aux_Id and then S = Scope (S1));
4780 end Defined_In_Scope;
4786 procedure Diagnose_Call (N : Node_Id; Nam : Node_Id) is
4792 Void_Interp_Seen : Boolean := False;
4795 pragma Warnings (Off, Boolean);
4798 if Ada_Version >= Ada_2005 then
4799 Actual := First_Actual (N);
4800 while Present (Actual) loop
4802 -- Ada 2005 (AI-50217): Post an error in case of premature
4803 -- usage of an entity from the limited view.
4805 if not Analyzed (Etype (Actual))
4806 and then From_With_Type (Etype (Actual))
4808 Error_Msg_Qual_Level := 1;
4810 ("missing with_clause for scope of imported type&",
4811 Actual, Etype (Actual));
4812 Error_Msg_Qual_Level := 0;
4815 Next_Actual (Actual);
4819 -- Analyze each candidate call again, with full error reporting
4823 ("no candidate interpretations match the actuals:!", Nam);
4824 Err_Mode := All_Errors_Mode;
4825 All_Errors_Mode := True;
4827 -- If this is a call to an operation of a concurrent type,
4828 -- the failed interpretations have been removed from the
4829 -- name. Recover them to provide full diagnostics.
4831 if Nkind (Parent (Nam)) = N_Selected_Component then
4832 Set_Entity (Nam, Empty);
4833 New_Nam := New_Copy_Tree (Parent (Nam));
4834 Set_Is_Overloaded (New_Nam, False);
4835 Set_Is_Overloaded (Selector_Name (New_Nam), False);
4836 Set_Parent (New_Nam, Parent (Parent (Nam)));
4837 Analyze_Selected_Component (New_Nam);
4838 Get_First_Interp (Selector_Name (New_Nam), X, It);
4840 Get_First_Interp (Nam, X, It);
4843 while Present (It.Nam) loop
4844 if Etype (It.Nam) = Standard_Void_Type then
4845 Void_Interp_Seen := True;
4848 Analyze_One_Call (N, It.Nam, True, Success);
4849 Get_Next_Interp (X, It);
4852 if Nkind (N) = N_Function_Call then
4853 Get_First_Interp (Nam, X, It);
4854 while Present (It.Nam) loop
4855 if Ekind_In (It.Nam, E_Function, E_Operator) then
4858 Get_Next_Interp (X, It);
4862 -- If all interpretations are procedures, this deserves a
4863 -- more precise message. Ditto if this appears as the prefix
4864 -- of a selected component, which may be a lexical error.
4867 ("\context requires function call, found procedure name", Nam);
4869 if Nkind (Parent (N)) = N_Selected_Component
4870 and then N = Prefix (Parent (N))
4872 Error_Msg_N -- CODEFIX
4873 ("\period should probably be semicolon", Parent (N));
4876 elsif Nkind (N) = N_Procedure_Call_Statement
4877 and then not Void_Interp_Seen
4880 "\function name found in procedure call", Nam);
4883 All_Errors_Mode := Err_Mode;
4886 ---------------------------
4887 -- Find_Arithmetic_Types --
4888 ---------------------------
4890 procedure Find_Arithmetic_Types
4895 Index1 : Interp_Index;
4896 Index2 : Interp_Index;
4900 procedure Check_Right_Argument (T : Entity_Id);
4901 -- Check right operand of operator
4903 --------------------------
4904 -- Check_Right_Argument --
4905 --------------------------
4907 procedure Check_Right_Argument (T : Entity_Id) is
4909 if not Is_Overloaded (R) then
4910 Check_Arithmetic_Pair (T, Etype (R), Op_Id, N);
4912 Get_First_Interp (R, Index2, It2);
4913 while Present (It2.Typ) loop
4914 Check_Arithmetic_Pair (T, It2.Typ, Op_Id, N);
4915 Get_Next_Interp (Index2, It2);
4918 end Check_Right_Argument;
4920 -- Start of processing for Find_Arithmetic_Types
4923 if not Is_Overloaded (L) then
4924 Check_Right_Argument (Etype (L));
4927 Get_First_Interp (L, Index1, It1);
4928 while Present (It1.Typ) loop
4929 Check_Right_Argument (It1.Typ);
4930 Get_Next_Interp (Index1, It1);
4934 end Find_Arithmetic_Types;
4936 ------------------------
4937 -- Find_Boolean_Types --
4938 ------------------------
4940 procedure Find_Boolean_Types
4945 Index : Interp_Index;
4948 procedure Check_Numeric_Argument (T : Entity_Id);
4949 -- Special case for logical operations one of whose operands is an
4950 -- integer literal. If both are literal the result is any modular type.
4952 ----------------------------
4953 -- Check_Numeric_Argument --
4954 ----------------------------
4956 procedure Check_Numeric_Argument (T : Entity_Id) is
4958 if T = Universal_Integer then
4959 Add_One_Interp (N, Op_Id, Any_Modular);
4961 elsif Is_Modular_Integer_Type (T) then
4962 Add_One_Interp (N, Op_Id, T);
4964 end Check_Numeric_Argument;
4966 -- Start of processing for Find_Boolean_Types
4969 if not Is_Overloaded (L) then
4970 if Etype (L) = Universal_Integer
4971 or else Etype (L) = Any_Modular
4973 if not Is_Overloaded (R) then
4974 Check_Numeric_Argument (Etype (R));
4977 Get_First_Interp (R, Index, It);
4978 while Present (It.Typ) loop
4979 Check_Numeric_Argument (It.Typ);
4980 Get_Next_Interp (Index, It);
4984 -- If operands are aggregates, we must assume that they may be
4985 -- boolean arrays, and leave disambiguation for the second pass.
4986 -- If only one is an aggregate, verify that the other one has an
4987 -- interpretation as a boolean array
4989 elsif Nkind (L) = N_Aggregate then
4990 if Nkind (R) = N_Aggregate then
4991 Add_One_Interp (N, Op_Id, Etype (L));
4993 elsif not Is_Overloaded (R) then
4994 if Valid_Boolean_Arg (Etype (R)) then
4995 Add_One_Interp (N, Op_Id, Etype (R));
4999 Get_First_Interp (R, Index, It);
5000 while Present (It.Typ) loop
5001 if Valid_Boolean_Arg (It.Typ) then
5002 Add_One_Interp (N, Op_Id, It.Typ);
5005 Get_Next_Interp (Index, It);
5009 elsif Valid_Boolean_Arg (Etype (L))
5010 and then Has_Compatible_Type (R, Etype (L))
5012 Add_One_Interp (N, Op_Id, Etype (L));
5016 Get_First_Interp (L, Index, It);
5017 while Present (It.Typ) loop
5018 if Valid_Boolean_Arg (It.Typ)
5019 and then Has_Compatible_Type (R, It.Typ)
5021 Add_One_Interp (N, Op_Id, It.Typ);
5024 Get_Next_Interp (Index, It);
5027 end Find_Boolean_Types;
5029 ---------------------------
5030 -- Find_Comparison_Types --
5031 ---------------------------
5033 procedure Find_Comparison_Types
5038 Index : Interp_Index;
5040 Found : Boolean := False;
5043 Scop : Entity_Id := Empty;
5045 procedure Try_One_Interp (T1 : Entity_Id);
5046 -- Routine to try one proposed interpretation. Note that the context
5047 -- of the operator plays no role in resolving the arguments, so that
5048 -- if there is more than one interpretation of the operands that is
5049 -- compatible with comparison, the operation is ambiguous.
5051 --------------------
5052 -- Try_One_Interp --
5053 --------------------
5055 procedure Try_One_Interp (T1 : Entity_Id) is
5058 -- If the operator is an expanded name, then the type of the operand
5059 -- must be defined in the corresponding scope. If the type is
5060 -- universal, the context will impose the correct type.
5063 and then not Defined_In_Scope (T1, Scop)
5064 and then T1 /= Universal_Integer
5065 and then T1 /= Universal_Real
5066 and then T1 /= Any_String
5067 and then T1 /= Any_Composite
5072 if Valid_Comparison_Arg (T1)
5073 and then Has_Compatible_Type (R, T1)
5076 and then Base_Type (T1) /= Base_Type (T_F)
5078 It := Disambiguate (L, I_F, Index, Any_Type);
5080 if It = No_Interp then
5081 Ambiguous_Operands (N);
5082 Set_Etype (L, Any_Type);
5096 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5101 -- Start of processing for Find_Comparison_Types
5104 -- If left operand is aggregate, the right operand has to
5105 -- provide a usable type for it.
5107 if Nkind (L) = N_Aggregate
5108 and then Nkind (R) /= N_Aggregate
5110 Find_Comparison_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5114 if Nkind (N) = N_Function_Call
5115 and then Nkind (Name (N)) = N_Expanded_Name
5117 Scop := Entity (Prefix (Name (N)));
5119 -- The prefix may be a package renaming, and the subsequent test
5120 -- requires the original package.
5122 if Ekind (Scop) = E_Package
5123 and then Present (Renamed_Entity (Scop))
5125 Scop := Renamed_Entity (Scop);
5126 Set_Entity (Prefix (Name (N)), Scop);
5130 if not Is_Overloaded (L) then
5131 Try_One_Interp (Etype (L));
5134 Get_First_Interp (L, Index, It);
5135 while Present (It.Typ) loop
5136 Try_One_Interp (It.Typ);
5137 Get_Next_Interp (Index, It);
5140 end Find_Comparison_Types;
5142 ----------------------------------------
5143 -- Find_Non_Universal_Interpretations --
5144 ----------------------------------------
5146 procedure Find_Non_Universal_Interpretations
5152 Index : Interp_Index;
5156 if T1 = Universal_Integer
5157 or else T1 = Universal_Real
5159 if not Is_Overloaded (R) then
5161 (N, Op_Id, Standard_Boolean, Base_Type (Etype (R)));
5163 Get_First_Interp (R, Index, It);
5164 while Present (It.Typ) loop
5165 if Covers (It.Typ, T1) then
5167 (N, Op_Id, Standard_Boolean, Base_Type (It.Typ));
5170 Get_Next_Interp (Index, It);
5174 Add_One_Interp (N, Op_Id, Standard_Boolean, Base_Type (T1));
5176 end Find_Non_Universal_Interpretations;
5178 ------------------------------
5179 -- Find_Concatenation_Types --
5180 ------------------------------
5182 procedure Find_Concatenation_Types
5187 Op_Type : constant Entity_Id := Etype (Op_Id);
5190 if Is_Array_Type (Op_Type)
5191 and then not Is_Limited_Type (Op_Type)
5193 and then (Has_Compatible_Type (L, Op_Type)
5195 Has_Compatible_Type (L, Component_Type (Op_Type)))
5197 and then (Has_Compatible_Type (R, Op_Type)
5199 Has_Compatible_Type (R, Component_Type (Op_Type)))
5201 Add_One_Interp (N, Op_Id, Op_Type);
5203 end Find_Concatenation_Types;
5205 -------------------------
5206 -- Find_Equality_Types --
5207 -------------------------
5209 procedure Find_Equality_Types
5214 Index : Interp_Index;
5216 Found : Boolean := False;
5219 Scop : Entity_Id := Empty;
5221 procedure Try_One_Interp (T1 : Entity_Id);
5222 -- The context of the equality operator plays no role in resolving the
5223 -- arguments, so that if there is more than one interpretation of the
5224 -- operands that is compatible with equality, the construct is ambiguous
5225 -- and an error can be emitted now, after trying to disambiguate, i.e.
5226 -- applying preference rules.
5228 --------------------
5229 -- Try_One_Interp --
5230 --------------------
5232 procedure Try_One_Interp (T1 : Entity_Id) is
5233 Bas : constant Entity_Id := Base_Type (T1);
5236 -- If the operator is an expanded name, then the type of the operand
5237 -- must be defined in the corresponding scope. If the type is
5238 -- universal, the context will impose the correct type. An anonymous
5239 -- type for a 'Access reference is also universal in this sense, as
5240 -- the actual type is obtained from context.
5241 -- In Ada 2005, the equality operator for anonymous access types
5242 -- is declared in Standard, and preference rules apply to it.
5244 if Present (Scop) then
5245 if Defined_In_Scope (T1, Scop)
5246 or else T1 = Universal_Integer
5247 or else T1 = Universal_Real
5248 or else T1 = Any_Access
5249 or else T1 = Any_String
5250 or else T1 = Any_Composite
5251 or else (Ekind (T1) = E_Access_Subprogram_Type
5252 and then not Comes_From_Source (T1))
5256 elsif Ekind (T1) = E_Anonymous_Access_Type
5257 and then Scop = Standard_Standard
5262 -- The scope does not contain an operator for the type
5267 -- If we have infix notation, the operator must be usable.
5268 -- Within an instance, if the type is already established we
5269 -- know it is correct.
5270 -- In Ada 2005, the equality on anonymous access types is declared
5271 -- in Standard, and is always visible.
5273 elsif In_Open_Scopes (Scope (Bas))
5274 or else Is_Potentially_Use_Visible (Bas)
5275 or else In_Use (Bas)
5276 or else (In_Use (Scope (Bas))
5277 and then not Is_Hidden (Bas))
5278 or else (In_Instance
5279 and then First_Subtype (T1) = First_Subtype (Etype (R)))
5280 or else Ekind (T1) = E_Anonymous_Access_Type
5285 -- Save candidate type for subsquent error message, if any
5287 if not Is_Limited_Type (T1) then
5288 Candidate_Type := T1;
5294 -- Ada 2005 (AI-230): Keep restriction imposed by Ada 83 and 95:
5295 -- Do not allow anonymous access types in equality operators.
5297 if Ada_Version < Ada_2005
5298 and then Ekind (T1) = E_Anonymous_Access_Type
5303 if T1 /= Standard_Void_Type
5304 and then not Is_Limited_Type (T1)
5305 and then not Is_Limited_Composite (T1)
5306 and then Has_Compatible_Type (R, T1)
5309 and then Base_Type (T1) /= Base_Type (T_F)
5311 It := Disambiguate (L, I_F, Index, Any_Type);
5313 if It = No_Interp then
5314 Ambiguous_Operands (N);
5315 Set_Etype (L, Any_Type);
5328 if not Analyzed (L) then
5332 Find_Non_Universal_Interpretations (N, R, Op_Id, T1);
5334 -- Case of operator was not visible, Etype still set to Any_Type
5336 if Etype (N) = Any_Type then
5340 elsif Scop = Standard_Standard
5341 and then Ekind (T1) = E_Anonymous_Access_Type
5347 -- Start of processing for Find_Equality_Types
5350 -- If left operand is aggregate, the right operand has to
5351 -- provide a usable type for it.
5353 if Nkind (L) = N_Aggregate
5354 and then Nkind (R) /= N_Aggregate
5356 Find_Equality_Types (L => R, R => L, Op_Id => Op_Id, N => N);
5360 if Nkind (N) = N_Function_Call
5361 and then Nkind (Name (N)) = N_Expanded_Name
5363 Scop := Entity (Prefix (Name (N)));
5365 -- The prefix may be a package renaming, and the subsequent test
5366 -- requires the original package.
5368 if Ekind (Scop) = E_Package
5369 and then Present (Renamed_Entity (Scop))
5371 Scop := Renamed_Entity (Scop);
5372 Set_Entity (Prefix (Name (N)), Scop);
5376 if not Is_Overloaded (L) then
5377 Try_One_Interp (Etype (L));
5380 Get_First_Interp (L, Index, It);
5381 while Present (It.Typ) loop
5382 Try_One_Interp (It.Typ);
5383 Get_Next_Interp (Index, It);
5386 end Find_Equality_Types;
5388 -------------------------
5389 -- Find_Negation_Types --
5390 -------------------------
5392 procedure Find_Negation_Types
5397 Index : Interp_Index;
5401 if not Is_Overloaded (R) then
5402 if Etype (R) = Universal_Integer then
5403 Add_One_Interp (N, Op_Id, Any_Modular);
5404 elsif Valid_Boolean_Arg (Etype (R)) then
5405 Add_One_Interp (N, Op_Id, Etype (R));
5409 Get_First_Interp (R, Index, It);
5410 while Present (It.Typ) loop
5411 if Valid_Boolean_Arg (It.Typ) then
5412 Add_One_Interp (N, Op_Id, It.Typ);
5415 Get_Next_Interp (Index, It);
5418 end Find_Negation_Types;
5420 ------------------------------
5421 -- Find_Primitive_Operation --
5422 ------------------------------
5424 function Find_Primitive_Operation (N : Node_Id) return Boolean is
5425 Obj : constant Node_Id := Prefix (N);
5426 Op : constant Node_Id := Selector_Name (N);
5433 Set_Etype (Op, Any_Type);
5435 if Is_Access_Type (Etype (Obj)) then
5436 Typ := Designated_Type (Etype (Obj));
5441 if Is_Class_Wide_Type (Typ) then
5442 Typ := Root_Type (Typ);
5445 Prims := Primitive_Operations (Typ);
5447 Prim := First_Elmt (Prims);
5448 while Present (Prim) loop
5449 if Chars (Node (Prim)) = Chars (Op) then
5450 Add_One_Interp (Op, Node (Prim), Etype (Node (Prim)));
5451 Set_Etype (N, Etype (Node (Prim)));
5457 -- Now look for class-wide operations of the type or any of its
5458 -- ancestors by iterating over the homonyms of the selector.
5461 Cls_Type : constant Entity_Id := Class_Wide_Type (Typ);
5465 Hom := Current_Entity (Op);
5466 while Present (Hom) loop
5467 if (Ekind (Hom) = E_Procedure
5469 Ekind (Hom) = E_Function)
5470 and then Scope (Hom) = Scope (Typ)
5471 and then Present (First_Formal (Hom))
5473 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
5475 (Is_Access_Type (Etype (First_Formal (Hom)))
5477 Ekind (Etype (First_Formal (Hom))) =
5478 E_Anonymous_Access_Type
5481 (Designated_Type (Etype (First_Formal (Hom)))) =
5484 Add_One_Interp (Op, Hom, Etype (Hom));
5485 Set_Etype (N, Etype (Hom));
5488 Hom := Homonym (Hom);
5492 return Etype (Op) /= Any_Type;
5493 end Find_Primitive_Operation;
5495 ----------------------
5496 -- Find_Unary_Types --
5497 ----------------------
5499 procedure Find_Unary_Types
5504 Index : Interp_Index;
5508 if not Is_Overloaded (R) then
5509 if Is_Numeric_Type (Etype (R)) then
5510 Add_One_Interp (N, Op_Id, Base_Type (Etype (R)));
5514 Get_First_Interp (R, Index, It);
5515 while Present (It.Typ) loop
5516 if Is_Numeric_Type (It.Typ) then
5517 Add_One_Interp (N, Op_Id, Base_Type (It.Typ));
5520 Get_Next_Interp (Index, It);
5523 end Find_Unary_Types;
5529 function Junk_Operand (N : Node_Id) return Boolean is
5533 if Error_Posted (N) then
5537 -- Get entity to be tested
5539 if Is_Entity_Name (N)
5540 and then Present (Entity (N))
5544 -- An odd case, a procedure name gets converted to a very peculiar
5545 -- function call, and here is where we detect this happening.
5547 elsif Nkind (N) = N_Function_Call
5548 and then Is_Entity_Name (Name (N))
5549 and then Present (Entity (Name (N)))
5553 -- Another odd case, there are at least some cases of selected
5554 -- components where the selected component is not marked as having
5555 -- an entity, even though the selector does have an entity
5557 elsif Nkind (N) = N_Selected_Component
5558 and then Present (Entity (Selector_Name (N)))
5560 Enode := Selector_Name (N);
5566 -- Now test the entity we got to see if it is a bad case
5568 case Ekind (Entity (Enode)) is
5572 ("package name cannot be used as operand", Enode);
5574 when Generic_Unit_Kind =>
5576 ("generic unit name cannot be used as operand", Enode);
5580 ("subtype name cannot be used as operand", Enode);
5584 ("entry name cannot be used as operand", Enode);
5588 ("procedure name cannot be used as operand", Enode);
5592 ("exception name cannot be used as operand", Enode);
5594 when E_Block | E_Label | E_Loop =>
5596 ("label name cannot be used as operand", Enode);
5606 --------------------
5607 -- Operator_Check --
5608 --------------------
5610 procedure Operator_Check (N : Node_Id) is
5612 Remove_Abstract_Operations (N);
5614 -- Test for case of no interpretation found for operator
5616 if Etype (N) = Any_Type then
5620 Op_Id : Entity_Id := Empty;
5623 R := Right_Opnd (N);
5625 if Nkind (N) in N_Binary_Op then
5631 -- If either operand has no type, then don't complain further,
5632 -- since this simply means that we have a propagated error.
5635 or else Etype (R) = Any_Type
5636 or else (Nkind (N) in N_Binary_Op and then Etype (L) = Any_Type)
5640 -- We explicitly check for the case of concatenation of component
5641 -- with component to avoid reporting spurious matching array types
5642 -- that might happen to be lurking in distant packages (such as
5643 -- run-time packages). This also prevents inconsistencies in the
5644 -- messages for certain ACVC B tests, which can vary depending on
5645 -- types declared in run-time interfaces. Another improvement when
5646 -- aggregates are present is to look for a well-typed operand.
5648 elsif Present (Candidate_Type)
5649 and then (Nkind (N) /= N_Op_Concat
5650 or else Is_Array_Type (Etype (L))
5651 or else Is_Array_Type (Etype (R)))
5654 if Nkind (N) = N_Op_Concat then
5655 if Etype (L) /= Any_Composite
5656 and then Is_Array_Type (Etype (L))
5658 Candidate_Type := Etype (L);
5660 elsif Etype (R) /= Any_Composite
5661 and then Is_Array_Type (Etype (R))
5663 Candidate_Type := Etype (R);
5667 Error_Msg_NE -- CODEFIX
5668 ("operator for} is not directly visible!",
5669 N, First_Subtype (Candidate_Type));
5670 Error_Msg_N -- CODEFIX
5671 ("use clause would make operation legal!", N);
5674 -- If either operand is a junk operand (e.g. package name), then
5675 -- post appropriate error messages, but do not complain further.
5677 -- Note that the use of OR in this test instead of OR ELSE is
5678 -- quite deliberate, we may as well check both operands in the
5679 -- binary operator case.
5681 elsif Junk_Operand (R)
5682 or (Nkind (N) in N_Binary_Op and then Junk_Operand (L))
5686 -- If we have a logical operator, one of whose operands is
5687 -- Boolean, then we know that the other operand cannot resolve to
5688 -- Boolean (since we got no interpretations), but in that case we
5689 -- pretty much know that the other operand should be Boolean, so
5690 -- resolve it that way (generating an error)
5692 elsif Nkind_In (N, N_Op_And, N_Op_Or, N_Op_Xor) then
5693 if Etype (L) = Standard_Boolean then
5694 Resolve (R, Standard_Boolean);
5696 elsif Etype (R) = Standard_Boolean then
5697 Resolve (L, Standard_Boolean);
5701 -- For an arithmetic operator or comparison operator, if one
5702 -- of the operands is numeric, then we know the other operand
5703 -- is not the same numeric type. If it is a non-numeric type,
5704 -- then probably it is intended to match the other operand.
5706 elsif Nkind_In (N, N_Op_Add,
5712 Nkind_In (N, N_Op_Lt,
5718 if Is_Numeric_Type (Etype (L))
5719 and then not Is_Numeric_Type (Etype (R))
5721 Resolve (R, Etype (L));
5724 elsif Is_Numeric_Type (Etype (R))
5725 and then not Is_Numeric_Type (Etype (L))
5727 Resolve (L, Etype (R));
5731 -- Comparisons on A'Access are common enough to deserve a
5734 elsif Nkind_In (N, N_Op_Eq, N_Op_Ne)
5735 and then Ekind (Etype (L)) = E_Access_Attribute_Type
5736 and then Ekind (Etype (R)) = E_Access_Attribute_Type
5739 ("two access attributes cannot be compared directly", N);
5741 ("\use qualified expression for one of the operands",
5745 -- Another one for C programmers
5747 elsif Nkind (N) = N_Op_Concat
5748 and then Valid_Boolean_Arg (Etype (L))
5749 and then Valid_Boolean_Arg (Etype (R))
5751 Error_Msg_N ("invalid operands for concatenation", N);
5752 Error_Msg_N -- CODEFIX
5753 ("\maybe AND was meant", N);
5756 -- A special case for comparison of access parameter with null
5758 elsif Nkind (N) = N_Op_Eq
5759 and then Is_Entity_Name (L)
5760 and then Nkind (Parent (Entity (L))) = N_Parameter_Specification
5761 and then Nkind (Parameter_Type (Parent (Entity (L)))) =
5763 and then Nkind (R) = N_Null
5765 Error_Msg_N ("access parameter is not allowed to be null", L);
5766 Error_Msg_N ("\(call would raise Constraint_Error)", L);
5769 -- Another special case for exponentiation, where the right
5770 -- operand must be Natural, independently of the base.
5772 elsif Nkind (N) = N_Op_Expon
5773 and then Is_Numeric_Type (Etype (L))
5774 and then not Is_Overloaded (R)
5776 First_Subtype (Base_Type (Etype (R))) /= Standard_Integer
5777 and then Base_Type (Etype (R)) /= Universal_Integer
5780 ("exponent must be of type Natural, found}", R, Etype (R));
5784 -- If we fall through then just give general message. Note that in
5785 -- the following messages, if the operand is overloaded we choose
5786 -- an arbitrary type to complain about, but that is probably more
5787 -- useful than not giving a type at all.
5789 if Nkind (N) in N_Unary_Op then
5790 Error_Msg_Node_2 := Etype (R);
5791 Error_Msg_N ("operator& not defined for}", N);
5795 if Nkind (N) in N_Binary_Op then
5796 if not Is_Overloaded (L)
5797 and then not Is_Overloaded (R)
5798 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
5800 Error_Msg_Node_2 := First_Subtype (Etype (R));
5801 Error_Msg_N ("there is no applicable operator& for}", N);
5804 -- Another attempt to find a fix: one of the candidate
5805 -- interpretations may not be use-visible. This has
5806 -- already been checked for predefined operators, so
5807 -- we examine only user-defined functions.
5809 Op_Id := Get_Name_Entity_Id (Chars (N));
5811 while Present (Op_Id) loop
5812 if Ekind (Op_Id) /= E_Operator
5813 and then Is_Overloadable (Op_Id)
5815 if not Is_Immediately_Visible (Op_Id)
5816 and then not In_Use (Scope (Op_Id))
5817 and then not Is_Abstract_Subprogram (Op_Id)
5818 and then not Is_Hidden (Op_Id)
5819 and then Ekind (Scope (Op_Id)) = E_Package
5822 (L, Etype (First_Formal (Op_Id)))
5824 (Next_Formal (First_Formal (Op_Id)))
5828 Etype (Next_Formal (First_Formal (Op_Id))))
5831 ("No legal interpretation for operator&", N);
5833 ("\use clause on& would make operation legal",
5839 Op_Id := Homonym (Op_Id);
5843 Error_Msg_N ("invalid operand types for operator&", N);
5845 if Nkind (N) /= N_Op_Concat then
5846 Error_Msg_NE ("\left operand has}!", N, Etype (L));
5847 Error_Msg_NE ("\right operand has}!", N, Etype (R));
5857 -----------------------------------------
5858 -- Process_Implicit_Dereference_Prefix --
5859 -----------------------------------------
5861 function Process_Implicit_Dereference_Prefix
5863 P : Entity_Id) return Entity_Id
5866 Typ : constant Entity_Id := Designated_Type (Etype (P));
5870 and then (Operating_Mode = Check_Semantics or else not Expander_Active)
5872 -- We create a dummy reference to E to ensure that the reference
5873 -- is not considered as part of an assignment (an implicit
5874 -- dereference can never assign to its prefix). The Comes_From_Source
5875 -- attribute needs to be propagated for accurate warnings.
5877 Ref := New_Reference_To (E, Sloc (P));
5878 Set_Comes_From_Source (Ref, Comes_From_Source (P));
5879 Generate_Reference (E, Ref);
5882 -- An implicit dereference is a legal occurrence of an
5883 -- incomplete type imported through a limited_with clause,
5884 -- if the full view is visible.
5886 if From_With_Type (Typ)
5887 and then not From_With_Type (Scope (Typ))
5889 (Is_Immediately_Visible (Scope (Typ))
5891 (Is_Child_Unit (Scope (Typ))
5892 and then Is_Visible_Child_Unit (Scope (Typ))))
5894 return Available_View (Typ);
5899 end Process_Implicit_Dereference_Prefix;
5901 --------------------------------
5902 -- Remove_Abstract_Operations --
5903 --------------------------------
5905 procedure Remove_Abstract_Operations (N : Node_Id) is
5906 Abstract_Op : Entity_Id := Empty;
5907 Address_Kludge : Boolean := False;
5911 -- AI-310: If overloaded, remove abstract non-dispatching operations. We
5912 -- activate this if either extensions are enabled, or if the abstract
5913 -- operation in question comes from a predefined file. This latter test
5914 -- allows us to use abstract to make operations invisible to users. In
5915 -- particular, if type Address is non-private and abstract subprograms
5916 -- are used to hide its operators, they will be truly hidden.
5918 type Operand_Position is (First_Op, Second_Op);
5919 Univ_Type : constant Entity_Id := Universal_Interpretation (N);
5921 procedure Remove_Address_Interpretations (Op : Operand_Position);
5922 -- Ambiguities may arise when the operands are literal and the address
5923 -- operations in s-auxdec are visible. In that case, remove the
5924 -- interpretation of a literal as Address, to retain the semantics of
5925 -- Address as a private type.
5927 ------------------------------------
5928 -- Remove_Address_Interpretations --
5929 ------------------------------------
5931 procedure Remove_Address_Interpretations (Op : Operand_Position) is
5935 if Is_Overloaded (N) then
5936 Get_First_Interp (N, I, It);
5937 while Present (It.Nam) loop
5938 Formal := First_Entity (It.Nam);
5940 if Op = Second_Op then
5941 Formal := Next_Entity (Formal);
5944 if Is_Descendent_Of_Address (Etype (Formal)) then
5945 Address_Kludge := True;
5949 Get_Next_Interp (I, It);
5952 end Remove_Address_Interpretations;
5954 -- Start of processing for Remove_Abstract_Operations
5957 if Is_Overloaded (N) then
5958 Get_First_Interp (N, I, It);
5960 while Present (It.Nam) loop
5961 if Is_Overloadable (It.Nam)
5962 and then Is_Abstract_Subprogram (It.Nam)
5963 and then not Is_Dispatching_Operation (It.Nam)
5965 Abstract_Op := It.Nam;
5967 if Is_Descendent_Of_Address (It.Typ) then
5968 Address_Kludge := True;
5972 -- In Ada 2005, this operation does not participate in Overload
5973 -- resolution. If the operation is defined in a predefined
5974 -- unit, it is one of the operations declared abstract in some
5975 -- variants of System, and it must be removed as well.
5977 elsif Ada_Version >= Ada_2005
5978 or else Is_Predefined_File_Name
5979 (Unit_File_Name (Get_Source_Unit (It.Nam)))
5986 Get_Next_Interp (I, It);
5989 if No (Abstract_Op) then
5991 -- If some interpretation yields an integer type, it is still
5992 -- possible that there are address interpretations. Remove them
5993 -- if one operand is a literal, to avoid spurious ambiguities
5994 -- on systems where Address is a visible integer type.
5996 if Is_Overloaded (N)
5997 and then Nkind (N) in N_Op
5998 and then Is_Integer_Type (Etype (N))
6000 if Nkind (N) in N_Binary_Op then
6001 if Nkind (Right_Opnd (N)) = N_Integer_Literal then
6002 Remove_Address_Interpretations (Second_Op);
6004 elsif Nkind (Right_Opnd (N)) = N_Integer_Literal then
6005 Remove_Address_Interpretations (First_Op);
6010 elsif Nkind (N) in N_Op then
6012 -- Remove interpretations that treat literals as addresses. This
6013 -- is never appropriate, even when Address is defined as a visible
6014 -- Integer type. The reason is that we would really prefer Address
6015 -- to behave as a private type, even in this case, which is there
6016 -- only to accommodate oddities of VMS address sizes. If Address
6017 -- is a visible integer type, we get lots of overload ambiguities.
6019 if Nkind (N) in N_Binary_Op then
6021 U1 : constant Boolean :=
6022 Present (Universal_Interpretation (Right_Opnd (N)));
6023 U2 : constant Boolean :=
6024 Present (Universal_Interpretation (Left_Opnd (N)));
6028 Remove_Address_Interpretations (Second_Op);
6032 Remove_Address_Interpretations (First_Op);
6035 if not (U1 and U2) then
6037 -- Remove corresponding predefined operator, which is
6038 -- always added to the overload set.
6040 Get_First_Interp (N, I, It);
6041 while Present (It.Nam) loop
6042 if Scope (It.Nam) = Standard_Standard
6043 and then Base_Type (It.Typ) =
6044 Base_Type (Etype (Abstract_Op))
6049 Get_Next_Interp (I, It);
6052 elsif Is_Overloaded (N)
6053 and then Present (Univ_Type)
6055 -- If both operands have a universal interpretation,
6056 -- it is still necessary to remove interpretations that
6057 -- yield Address. Any remaining ambiguities will be
6058 -- removed in Disambiguate.
6060 Get_First_Interp (N, I, It);
6061 while Present (It.Nam) loop
6062 if Is_Descendent_Of_Address (It.Typ) then
6065 elsif not Is_Type (It.Nam) then
6066 Set_Entity (N, It.Nam);
6069 Get_Next_Interp (I, It);
6075 elsif Nkind (N) = N_Function_Call
6077 (Nkind (Name (N)) = N_Operator_Symbol
6079 (Nkind (Name (N)) = N_Expanded_Name
6081 Nkind (Selector_Name (Name (N))) = N_Operator_Symbol))
6085 Arg1 : constant Node_Id := First (Parameter_Associations (N));
6086 U1 : constant Boolean :=
6087 Present (Universal_Interpretation (Arg1));
6088 U2 : constant Boolean :=
6089 Present (Next (Arg1)) and then
6090 Present (Universal_Interpretation (Next (Arg1)));
6094 Remove_Address_Interpretations (First_Op);
6098 Remove_Address_Interpretations (Second_Op);
6101 if not (U1 and U2) then
6102 Get_First_Interp (N, I, It);
6103 while Present (It.Nam) loop
6104 if Scope (It.Nam) = Standard_Standard
6105 and then It.Typ = Base_Type (Etype (Abstract_Op))
6110 Get_Next_Interp (I, It);
6116 -- If the removal has left no valid interpretations, emit an error
6117 -- message now and label node as illegal.
6119 if Present (Abstract_Op) then
6120 Get_First_Interp (N, I, It);
6124 -- Removal of abstract operation left no viable candidate
6126 Set_Etype (N, Any_Type);
6127 Error_Msg_Sloc := Sloc (Abstract_Op);
6129 ("cannot call abstract operation& declared#", N, Abstract_Op);
6131 -- In Ada 2005, an abstract operation may disable predefined
6132 -- operators. Since the context is not yet known, we mark the
6133 -- predefined operators as potentially hidden. Do not include
6134 -- predefined operators when addresses are involved since this
6135 -- case is handled separately.
6137 elsif Ada_Version >= Ada_2005
6138 and then not Address_Kludge
6140 while Present (It.Nam) loop
6141 if Is_Numeric_Type (It.Typ)
6142 and then Scope (It.Typ) = Standard_Standard
6144 Set_Abstract_Op (I, Abstract_Op);
6147 Get_Next_Interp (I, It);
6152 end Remove_Abstract_Operations;
6154 -----------------------
6155 -- Try_Indirect_Call --
6156 -----------------------
6158 function Try_Indirect_Call
6161 Typ : Entity_Id) return Boolean
6167 pragma Warnings (Off, Call_OK);
6170 Normalize_Actuals (N, Designated_Type (Typ), False, Call_OK);
6172 Actual := First_Actual (N);
6173 Formal := First_Formal (Designated_Type (Typ));
6174 while Present (Actual) and then Present (Formal) loop
6175 if not Has_Compatible_Type (Actual, Etype (Formal)) then
6180 Next_Formal (Formal);
6183 if No (Actual) and then No (Formal) then
6184 Add_One_Interp (N, Nam, Etype (Designated_Type (Typ)));
6186 -- Nam is a candidate interpretation for the name in the call,
6187 -- if it is not an indirect call.
6189 if not Is_Type (Nam)
6190 and then Is_Entity_Name (Name (N))
6192 Set_Entity (Name (N), Nam);
6199 end Try_Indirect_Call;
6201 ----------------------
6202 -- Try_Indexed_Call --
6203 ----------------------
6205 function Try_Indexed_Call
6209 Skip_First : Boolean) return Boolean
6211 Loc : constant Source_Ptr := Sloc (N);
6212 Actuals : constant List_Id := Parameter_Associations (N);
6217 Actual := First (Actuals);
6219 -- If the call was originally written in prefix form, skip the first
6220 -- actual, which is obviously not defaulted.
6226 Index := First_Index (Typ);
6227 while Present (Actual) and then Present (Index) loop
6229 -- If the parameter list has a named association, the expression
6230 -- is definitely a call and not an indexed component.
6232 if Nkind (Actual) = N_Parameter_Association then
6236 if Is_Entity_Name (Actual)
6237 and then Is_Type (Entity (Actual))
6238 and then No (Next (Actual))
6240 -- A single actual that is a type name indicates a slice if the
6241 -- type is discrete, and an error otherwise.
6243 if Is_Discrete_Type (Entity (Actual)) then
6247 Make_Function_Call (Loc,
6248 Name => Relocate_Node (Name (N))),
6250 New_Occurrence_Of (Entity (Actual), Sloc (Actual))));
6255 Error_Msg_N ("invalid use of type in expression", Actual);
6256 Set_Etype (N, Any_Type);
6261 elsif not Has_Compatible_Type (Actual, Etype (Index)) then
6269 if No (Actual) and then No (Index) then
6270 Add_One_Interp (N, Nam, Component_Type (Typ));
6272 -- Nam is a candidate interpretation for the name in the call,
6273 -- if it is not an indirect call.
6275 if not Is_Type (Nam)
6276 and then Is_Entity_Name (Name (N))
6278 Set_Entity (Name (N), Nam);
6285 end Try_Indexed_Call;
6287 --------------------------
6288 -- Try_Object_Operation --
6289 --------------------------
6291 function Try_Object_Operation (N : Node_Id) return Boolean is
6292 K : constant Node_Kind := Nkind (Parent (N));
6293 Is_Subprg_Call : constant Boolean := Nkind_In
6294 (K, N_Procedure_Call_Statement,
6296 Loc : constant Source_Ptr := Sloc (N);
6297 Obj : constant Node_Id := Prefix (N);
6299 Subprog : constant Node_Id :=
6300 Make_Identifier (Sloc (Selector_Name (N)),
6301 Chars => Chars (Selector_Name (N)));
6302 -- Identifier on which possible interpretations will be collected
6304 Report_Error : Boolean := False;
6305 -- If no candidate interpretation matches the context, redo the
6306 -- analysis with error enabled to provide additional information.
6309 Candidate : Entity_Id := Empty;
6310 New_Call_Node : Node_Id := Empty;
6311 Node_To_Replace : Node_Id;
6312 Obj_Type : Entity_Id := Etype (Obj);
6313 Success : Boolean := False;
6315 function Valid_Candidate
6318 Subp : Entity_Id) return Entity_Id;
6319 -- If the subprogram is a valid interpretation, record it, and add
6320 -- to the list of interpretations of Subprog.
6322 procedure Complete_Object_Operation
6323 (Call_Node : Node_Id;
6324 Node_To_Replace : Node_Id);
6325 -- Make Subprog the name of Call_Node, replace Node_To_Replace with
6326 -- Call_Node, insert the object (or its dereference) as the first actual
6327 -- in the call, and complete the analysis of the call.
6329 procedure Report_Ambiguity (Op : Entity_Id);
6330 -- If a prefixed procedure call is ambiguous, indicate whether the
6331 -- call includes an implicit dereference or an implicit 'Access.
6333 procedure Transform_Object_Operation
6334 (Call_Node : out Node_Id;
6335 Node_To_Replace : out Node_Id);
6336 -- Transform Obj.Operation (X, Y,,) into Operation (Obj, X, Y ..)
6337 -- Call_Node is the resulting subprogram call, Node_To_Replace is
6338 -- either N or the parent of N, and Subprog is a reference to the
6339 -- subprogram we are trying to match.
6341 function Try_Class_Wide_Operation
6342 (Call_Node : Node_Id;
6343 Node_To_Replace : Node_Id) return Boolean;
6344 -- Traverse all ancestor types looking for a class-wide subprogram
6345 -- for which the current operation is a valid non-dispatching call.
6347 procedure Try_One_Prefix_Interpretation (T : Entity_Id);
6348 -- If prefix is overloaded, its interpretation may include different
6349 -- tagged types, and we must examine the primitive operations and
6350 -- the class-wide operations of each in order to find candidate
6351 -- interpretations for the call as a whole.
6353 function Try_Primitive_Operation
6354 (Call_Node : Node_Id;
6355 Node_To_Replace : Node_Id) return Boolean;
6356 -- Traverse the list of primitive subprograms looking for a dispatching
6357 -- operation for which the current node is a valid call .
6359 ---------------------
6360 -- Valid_Candidate --
6361 ---------------------
6363 function Valid_Candidate
6366 Subp : Entity_Id) return Entity_Id
6368 Arr_Type : Entity_Id;
6369 Comp_Type : Entity_Id;
6372 -- If the subprogram is a valid interpretation, record it in global
6373 -- variable Subprog, to collect all possible overloadings.
6376 if Subp /= Entity (Subprog) then
6377 Add_One_Interp (Subprog, Subp, Etype (Subp));
6381 -- If the call may be an indexed call, retrieve component type of
6382 -- resulting expression, and add possible interpretation.
6387 if Nkind (Call) = N_Function_Call
6388 and then Nkind (Parent (N)) = N_Indexed_Component
6389 and then Needs_One_Actual (Subp)
6391 if Is_Array_Type (Etype (Subp)) then
6392 Arr_Type := Etype (Subp);
6394 elsif Is_Access_Type (Etype (Subp))
6395 and then Is_Array_Type (Designated_Type (Etype (Subp)))
6397 Arr_Type := Designated_Type (Etype (Subp));
6401 if Present (Arr_Type) then
6403 -- Verify that the actuals (excluding the object) match the types
6411 Actual := Next (First_Actual (Call));
6412 Index := First_Index (Arr_Type);
6413 while Present (Actual) and then Present (Index) loop
6414 if not Has_Compatible_Type (Actual, Etype (Index)) then
6419 Next_Actual (Actual);
6425 and then Present (Arr_Type)
6427 Comp_Type := Component_Type (Arr_Type);
6431 if Present (Comp_Type)
6432 and then Etype (Subprog) /= Comp_Type
6434 Add_One_Interp (Subprog, Subp, Comp_Type);
6438 if Etype (Call) /= Any_Type then
6443 end Valid_Candidate;
6445 -------------------------------
6446 -- Complete_Object_Operation --
6447 -------------------------------
6449 procedure Complete_Object_Operation
6450 (Call_Node : Node_Id;
6451 Node_To_Replace : Node_Id)
6453 Control : constant Entity_Id := First_Formal (Entity (Subprog));
6454 Formal_Type : constant Entity_Id := Etype (Control);
6455 First_Actual : Node_Id;
6458 -- Place the name of the operation, with its interpretations,
6459 -- on the rewritten call.
6461 Set_Name (Call_Node, Subprog);
6463 First_Actual := First (Parameter_Associations (Call_Node));
6465 -- For cross-reference purposes, treat the new node as being in
6466 -- the source if the original one is.
6468 Set_Comes_From_Source (Subprog, Comes_From_Source (N));
6469 Set_Comes_From_Source (Call_Node, Comes_From_Source (N));
6471 if Nkind (N) = N_Selected_Component
6472 and then not Inside_A_Generic
6474 Set_Entity (Selector_Name (N), Entity (Subprog));
6477 -- If need be, rewrite first actual as an explicit dereference
6478 -- If the call is overloaded, the rewriting can only be done
6479 -- once the primitive operation is identified.
6481 if Is_Overloaded (Subprog) then
6483 -- The prefix itself may be overloaded, and its interpretations
6484 -- must be propagated to the new actual in the call.
6486 if Is_Overloaded (Obj) then
6487 Save_Interps (Obj, First_Actual);
6490 Rewrite (First_Actual, Obj);
6492 elsif not Is_Access_Type (Formal_Type)
6493 and then Is_Access_Type (Etype (Obj))
6495 Rewrite (First_Actual,
6496 Make_Explicit_Dereference (Sloc (Obj), Obj));
6497 Analyze (First_Actual);
6499 -- If we need to introduce an explicit dereference, verify that
6500 -- the resulting actual is compatible with the mode of the formal.
6502 if Ekind (First_Formal (Entity (Subprog))) /= E_In_Parameter
6503 and then Is_Access_Constant (Etype (Obj))
6506 ("expect variable in call to&", Prefix (N), Entity (Subprog));
6509 -- Conversely, if the formal is an access parameter and the object
6510 -- is not, replace the actual with a 'Access reference. Its analysis
6511 -- will check that the object is aliased.
6513 elsif Is_Access_Type (Formal_Type)
6514 and then not Is_Access_Type (Etype (Obj))
6516 -- A special case: A.all'access is illegal if A is an access to a
6517 -- constant and the context requires an access to a variable.
6519 if not Is_Access_Constant (Formal_Type) then
6520 if (Nkind (Obj) = N_Explicit_Dereference
6521 and then Is_Access_Constant (Etype (Prefix (Obj))))
6522 or else not Is_Variable (Obj)
6525 ("actual for& must be a variable", Obj, Control);
6529 Rewrite (First_Actual,
6530 Make_Attribute_Reference (Loc,
6531 Attribute_Name => Name_Access,
6532 Prefix => Relocate_Node (Obj)));
6534 if not Is_Aliased_View (Obj) then
6536 ("object in prefixed call to& must be aliased"
6537 & " (RM-2005 4.3.1 (13))",
6538 Prefix (First_Actual), Subprog);
6541 Analyze (First_Actual);
6544 if Is_Overloaded (Obj) then
6545 Save_Interps (Obj, First_Actual);
6548 Rewrite (First_Actual, Obj);
6551 Rewrite (Node_To_Replace, Call_Node);
6553 -- Propagate the interpretations collected in subprog to the new
6554 -- function call node, to be resolved from context.
6556 if Is_Overloaded (Subprog) then
6557 Save_Interps (Subprog, Node_To_Replace);
6560 Analyze (Node_To_Replace);
6562 -- If the operation has been rewritten into a call, which may get
6563 -- subsequently an explicit dereference, preserve the type on the
6564 -- original node (selected component or indexed component) for
6565 -- subsequent legality tests, e.g. Is_Variable. which examines
6566 -- the original node.
6568 if Nkind (Node_To_Replace) = N_Function_Call then
6570 (Original_Node (Node_To_Replace), Etype (Node_To_Replace));
6573 end Complete_Object_Operation;
6575 ----------------------
6576 -- Report_Ambiguity --
6577 ----------------------
6579 procedure Report_Ambiguity (Op : Entity_Id) is
6580 Access_Formal : constant Boolean :=
6581 Is_Access_Type (Etype (First_Formal (Op)));
6582 Access_Actual : constant Boolean :=
6583 Is_Access_Type (Etype (Prefix (N)));
6586 Error_Msg_Sloc := Sloc (Op);
6588 if Access_Formal and then not Access_Actual then
6589 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6591 ("\possible interpretation"
6592 & " (inherited, with implicit 'Access) #", N);
6595 ("\possible interpretation (with implicit 'Access) #", N);
6598 elsif not Access_Formal and then Access_Actual then
6599 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6601 ("\possible interpretation"
6602 & " ( inherited, with implicit dereference) #", N);
6605 ("\possible interpretation (with implicit dereference) #", N);
6609 if Nkind (Parent (Op)) = N_Full_Type_Declaration then
6610 Error_Msg_N ("\possible interpretation (inherited)#", N);
6612 Error_Msg_N -- CODEFIX
6613 ("\possible interpretation#", N);
6616 end Report_Ambiguity;
6618 --------------------------------
6619 -- Transform_Object_Operation --
6620 --------------------------------
6622 procedure Transform_Object_Operation
6623 (Call_Node : out Node_Id;
6624 Node_To_Replace : out Node_Id)
6626 Dummy : constant Node_Id := New_Copy (Obj);
6627 -- Placeholder used as a first parameter in the call, replaced
6628 -- eventually by the proper object.
6630 Parent_Node : constant Node_Id := Parent (N);
6636 -- Common case covering 1) Call to a procedure and 2) Call to a
6637 -- function that has some additional actuals.
6639 if Nkind_In (Parent_Node, N_Function_Call,
6640 N_Procedure_Call_Statement)
6642 -- N is a selected component node containing the name of the
6643 -- subprogram. If N is not the name of the parent node we must
6644 -- not replace the parent node by the new construct. This case
6645 -- occurs when N is a parameterless call to a subprogram that
6646 -- is an actual parameter of a call to another subprogram. For
6648 -- Some_Subprogram (..., Obj.Operation, ...)
6650 and then Name (Parent_Node) = N
6652 Node_To_Replace := Parent_Node;
6654 Actuals := Parameter_Associations (Parent_Node);
6656 if Present (Actuals) then
6657 Prepend (Dummy, Actuals);
6659 Actuals := New_List (Dummy);
6662 if Nkind (Parent_Node) = N_Procedure_Call_Statement then
6664 Make_Procedure_Call_Statement (Loc,
6665 Name => New_Copy (Subprog),
6666 Parameter_Associations => Actuals);
6670 Make_Function_Call (Loc,
6671 Name => New_Copy (Subprog),
6672 Parameter_Associations => Actuals);
6676 -- Before analysis, a function call appears as an indexed component
6677 -- if there are no named associations.
6679 elsif Nkind (Parent_Node) = N_Indexed_Component
6680 and then N = Prefix (Parent_Node)
6682 Node_To_Replace := Parent_Node;
6683 Actuals := Expressions (Parent_Node);
6685 Actual := First (Actuals);
6686 while Present (Actual) loop
6691 Prepend (Dummy, Actuals);
6694 Make_Function_Call (Loc,
6695 Name => New_Copy (Subprog),
6696 Parameter_Associations => Actuals);
6698 -- Parameterless call: Obj.F is rewritten as F (Obj)
6701 Node_To_Replace := N;
6704 Make_Function_Call (Loc,
6705 Name => New_Copy (Subprog),
6706 Parameter_Associations => New_List (Dummy));
6708 end Transform_Object_Operation;
6710 ------------------------------
6711 -- Try_Class_Wide_Operation --
6712 ------------------------------
6714 function Try_Class_Wide_Operation
6715 (Call_Node : Node_Id;
6716 Node_To_Replace : Node_Id) return Boolean
6718 Anc_Type : Entity_Id;
6719 Matching_Op : Entity_Id := Empty;
6722 procedure Traverse_Homonyms
6723 (Anc_Type : Entity_Id;
6724 Error : out Boolean);
6725 -- Traverse the homonym chain of the subprogram searching for those
6726 -- homonyms whose first formal has the Anc_Type's class-wide type,
6727 -- or an anonymous access type designating the class-wide type. If
6728 -- an ambiguity is detected, then Error is set to True.
6730 procedure Traverse_Interfaces
6731 (Anc_Type : Entity_Id;
6732 Error : out Boolean);
6733 -- Traverse the list of interfaces, if any, associated with Anc_Type
6734 -- and search for acceptable class-wide homonyms associated with each
6735 -- interface. If an ambiguity is detected, then Error is set to True.
6737 -----------------------
6738 -- Traverse_Homonyms --
6739 -----------------------
6741 procedure Traverse_Homonyms
6742 (Anc_Type : Entity_Id;
6743 Error : out Boolean)
6745 Cls_Type : Entity_Id;
6753 Cls_Type := Class_Wide_Type (Anc_Type);
6755 Hom := Current_Entity (Subprog);
6757 -- Find operation whose first parameter is of the class-wide
6758 -- type, a subtype thereof, or an anonymous access to same.
6760 while Present (Hom) loop
6761 if (Ekind (Hom) = E_Procedure
6763 Ekind (Hom) = E_Function)
6764 and then Scope (Hom) = Scope (Anc_Type)
6765 and then Present (First_Formal (Hom))
6767 (Base_Type (Etype (First_Formal (Hom))) = Cls_Type
6769 (Is_Access_Type (Etype (First_Formal (Hom)))
6771 Ekind (Etype (First_Formal (Hom))) =
6772 E_Anonymous_Access_Type
6775 (Designated_Type (Etype (First_Formal (Hom)))) =
6778 Set_Etype (Call_Node, Any_Type);
6779 Set_Is_Overloaded (Call_Node, False);
6782 if No (Matching_Op) then
6783 Hom_Ref := New_Reference_To (Hom, Sloc (Subprog));
6784 Set_Etype (Call_Node, Any_Type);
6785 Set_Parent (Call_Node, Parent (Node_To_Replace));
6787 Set_Name (Call_Node, Hom_Ref);
6792 Report => Report_Error,
6794 Skip_First => True);
6797 Valid_Candidate (Success, Call_Node, Hom);
6803 Report => Report_Error,
6805 Skip_First => True);
6807 if Present (Valid_Candidate (Success, Call_Node, Hom))
6808 and then Nkind (Call_Node) /= N_Function_Call
6810 Error_Msg_NE ("ambiguous call to&", N, Hom);
6811 Report_Ambiguity (Matching_Op);
6812 Report_Ambiguity (Hom);
6819 Hom := Homonym (Hom);
6821 end Traverse_Homonyms;
6823 -------------------------
6824 -- Traverse_Interfaces --
6825 -------------------------
6827 procedure Traverse_Interfaces
6828 (Anc_Type : Entity_Id;
6829 Error : out Boolean)
6831 Intface_List : constant List_Id :=
6832 Abstract_Interface_List (Anc_Type);
6838 if Is_Non_Empty_List (Intface_List) then
6839 Intface := First (Intface_List);
6840 while Present (Intface) loop
6842 -- Look for acceptable class-wide homonyms associated with
6845 Traverse_Homonyms (Etype (Intface), Error);
6851 -- Continue the search by looking at each of the interface's
6852 -- associated interface ancestors.
6854 Traverse_Interfaces (Etype (Intface), Error);
6863 end Traverse_Interfaces;
6865 -- Start of processing for Try_Class_Wide_Operation
6868 -- Loop through ancestor types (including interfaces), traversing
6869 -- the homonym chain of the subprogram, trying out those homonyms
6870 -- whose first formal has the class-wide type of the ancestor, or
6871 -- an anonymous access type designating the class-wide type.
6873 Anc_Type := Obj_Type;
6875 -- Look for a match among homonyms associated with the ancestor
6877 Traverse_Homonyms (Anc_Type, Error);
6883 -- Continue the search for matches among homonyms associated with
6884 -- any interfaces implemented by the ancestor.
6886 Traverse_Interfaces (Anc_Type, Error);
6892 exit when Etype (Anc_Type) = Anc_Type;
6893 Anc_Type := Etype (Anc_Type);
6896 if Present (Matching_Op) then
6897 Set_Etype (Call_Node, Etype (Matching_Op));
6900 return Present (Matching_Op);
6901 end Try_Class_Wide_Operation;
6903 -----------------------------------
6904 -- Try_One_Prefix_Interpretation --
6905 -----------------------------------
6907 procedure Try_One_Prefix_Interpretation (T : Entity_Id) is
6911 if Is_Access_Type (Obj_Type) then
6912 Obj_Type := Designated_Type (Obj_Type);
6915 if Ekind (Obj_Type) = E_Private_Subtype then
6916 Obj_Type := Base_Type (Obj_Type);
6919 if Is_Class_Wide_Type (Obj_Type) then
6920 Obj_Type := Etype (Class_Wide_Type (Obj_Type));
6923 -- The type may have be obtained through a limited_with clause,
6924 -- in which case the primitive operations are available on its
6925 -- non-limited view. If still incomplete, retrieve full view.
6927 if Ekind (Obj_Type) = E_Incomplete_Type
6928 and then From_With_Type (Obj_Type)
6930 Obj_Type := Get_Full_View (Non_Limited_View (Obj_Type));
6933 -- If the object is not tagged, or the type is still an incomplete
6934 -- type, this is not a prefixed call.
6936 if not Is_Tagged_Type (Obj_Type)
6937 or else Is_Incomplete_Type (Obj_Type)
6942 if Try_Primitive_Operation
6943 (Call_Node => New_Call_Node,
6944 Node_To_Replace => Node_To_Replace)
6946 Try_Class_Wide_Operation
6947 (Call_Node => New_Call_Node,
6948 Node_To_Replace => Node_To_Replace)
6952 end Try_One_Prefix_Interpretation;
6954 -----------------------------
6955 -- Try_Primitive_Operation --
6956 -----------------------------
6958 function Try_Primitive_Operation
6959 (Call_Node : Node_Id;
6960 Node_To_Replace : Node_Id) return Boolean
6963 Prim_Op : Entity_Id;
6964 Matching_Op : Entity_Id := Empty;
6965 Prim_Op_Ref : Node_Id := Empty;
6967 Corr_Type : Entity_Id := Empty;
6968 -- If the prefix is a synchronized type, the controlling type of
6969 -- the primitive operation is the corresponding record type, else
6970 -- this is the object type itself.
6972 Success : Boolean := False;
6974 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id;
6975 -- For tagged types the candidate interpretations are found in
6976 -- the list of primitive operations of the type and its ancestors.
6977 -- For formal tagged types we have to find the operations declared
6978 -- in the same scope as the type (including in the generic formal
6979 -- part) because the type itself carries no primitive operations,
6980 -- except for formal derived types that inherit the operations of
6981 -- the parent and progenitors.
6982 -- If the context is a generic subprogram body, the generic formals
6983 -- are visible by name, but are not in the entity list of the
6984 -- subprogram because that list starts with the subprogram formals.
6985 -- We retrieve the candidate operations from the generic declaration.
6987 function Is_Private_Overriding (Op : Entity_Id) return Boolean;
6988 -- An operation that overrides an inherited operation in the private
6989 -- part of its package may be hidden, but if the inherited operation
6990 -- is visible a direct call to it will dispatch to the private one,
6991 -- which is therefore a valid candidate.
6993 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean;
6994 -- Verify that the prefix, dereferenced if need be, is a valid
6995 -- controlling argument in a call to Op. The remaining actuals
6996 -- are checked in the subsequent call to Analyze_One_Call.
6998 ------------------------------
6999 -- Collect_Generic_Type_Ops --
7000 ------------------------------
7002 function Collect_Generic_Type_Ops (T : Entity_Id) return Elist_Id is
7003 Bas : constant Entity_Id := Base_Type (T);
7004 Candidates : constant Elist_Id := New_Elmt_List;
7008 procedure Check_Candidate;
7009 -- The operation is a candidate if its first parameter is a
7010 -- controlling operand of the desired type.
7012 -----------------------
7013 -- Check_Candidate; --
7014 -----------------------
7016 procedure Check_Candidate is
7018 Formal := First_Formal (Subp);
7021 and then Is_Controlling_Formal (Formal)
7023 (Base_Type (Etype (Formal)) = Bas
7025 (Is_Access_Type (Etype (Formal))
7026 and then Designated_Type (Etype (Formal)) = Bas))
7028 Append_Elmt (Subp, Candidates);
7030 end Check_Candidate;
7032 -- Start of processing for Collect_Generic_Type_Ops
7035 if Is_Derived_Type (T) then
7036 return Primitive_Operations (T);
7038 elsif Ekind_In (Scope (T), E_Procedure, E_Function) then
7040 -- Scan the list of generic formals to find subprograms
7041 -- that may have a first controlling formal of the type.
7043 if Nkind (Unit_Declaration_Node (Scope (T)))
7044 = N_Generic_Subprogram_Declaration
7051 First (Generic_Formal_Declarations
7052 (Unit_Declaration_Node (Scope (T))));
7053 while Present (Decl) loop
7054 if Nkind (Decl) in N_Formal_Subprogram_Declaration then
7055 Subp := Defining_Entity (Decl);
7066 -- Scan the list of entities declared in the same scope as
7067 -- the type. In general this will be an open scope, given that
7068 -- the call we are analyzing can only appear within a generic
7069 -- declaration or body (either the one that declares T, or a
7072 -- For a subtype representing a generic actual type, go to the
7075 if Is_Generic_Actual_Type (T) then
7076 Subp := First_Entity (Scope (Base_Type (T)));
7078 Subp := First_Entity (Scope (T));
7081 while Present (Subp) loop
7082 if Is_Overloadable (Subp) then
7091 end Collect_Generic_Type_Ops;
7093 ---------------------------
7094 -- Is_Private_Overriding --
7095 ---------------------------
7097 function Is_Private_Overriding (Op : Entity_Id) return Boolean is
7098 Visible_Op : constant Entity_Id := Homonym (Op);
7101 return Present (Visible_Op)
7102 and then Scope (Op) = Scope (Visible_Op)
7103 and then not Comes_From_Source (Visible_Op)
7104 and then Alias (Visible_Op) = Op
7105 and then not Is_Hidden (Visible_Op);
7106 end Is_Private_Overriding;
7108 -----------------------------
7109 -- Valid_First_Argument_Of --
7110 -----------------------------
7112 function Valid_First_Argument_Of (Op : Entity_Id) return Boolean is
7113 Typ : Entity_Id := Etype (First_Formal (Op));
7116 if Is_Concurrent_Type (Typ)
7117 and then Present (Corresponding_Record_Type (Typ))
7119 Typ := Corresponding_Record_Type (Typ);
7122 -- Simple case. Object may be a subtype of the tagged type or
7123 -- may be the corresponding record of a synchronized type.
7125 return Obj_Type = Typ
7126 or else Base_Type (Obj_Type) = Typ
7127 or else Corr_Type = Typ
7129 -- Prefix can be dereferenced
7132 (Is_Access_Type (Corr_Type)
7133 and then Designated_Type (Corr_Type) = Typ)
7135 -- Formal is an access parameter, for which the object
7136 -- can provide an access.
7139 (Ekind (Typ) = E_Anonymous_Access_Type
7140 and then Designated_Type (Typ) = Base_Type (Corr_Type));
7141 end Valid_First_Argument_Of;
7143 -- Start of processing for Try_Primitive_Operation
7146 -- Look for subprograms in the list of primitive operations. The name
7147 -- must be identical, and the kind of call indicates the expected
7148 -- kind of operation (function or procedure). If the type is a
7149 -- (tagged) synchronized type, the primitive ops are attached to the
7150 -- corresponding record (base) type.
7152 if Is_Concurrent_Type (Obj_Type) then
7153 if Present (Corresponding_Record_Type (Obj_Type)) then
7154 Corr_Type := Base_Type (Corresponding_Record_Type (Obj_Type));
7155 Elmt := First_Elmt (Primitive_Operations (Corr_Type));
7157 Corr_Type := Obj_Type;
7158 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7161 elsif not Is_Generic_Type (Obj_Type) then
7162 Corr_Type := Obj_Type;
7163 Elmt := First_Elmt (Primitive_Operations (Obj_Type));
7166 Corr_Type := Obj_Type;
7167 Elmt := First_Elmt (Collect_Generic_Type_Ops (Obj_Type));
7170 while Present (Elmt) loop
7171 Prim_Op := Node (Elmt);
7173 if Chars (Prim_Op) = Chars (Subprog)
7174 and then Present (First_Formal (Prim_Op))
7175 and then Valid_First_Argument_Of (Prim_Op)
7177 (Nkind (Call_Node) = N_Function_Call)
7178 = (Ekind (Prim_Op) = E_Function)
7180 -- Ada 2005 (AI-251): If this primitive operation corresponds
7181 -- with an immediate ancestor interface there is no need to add
7182 -- it to the list of interpretations; the corresponding aliased
7183 -- primitive is also in this list of primitive operations and
7184 -- will be used instead.
7186 if (Present (Interface_Alias (Prim_Op))
7187 and then Is_Ancestor (Find_Dispatching_Type
7188 (Alias (Prim_Op)), Corr_Type))
7190 -- Do not consider hidden primitives unless the type is in an
7191 -- open scope or we are within an instance, where visibility
7192 -- is known to be correct, or else if this is an overriding
7193 -- operation in the private part for an inherited operation.
7195 or else (Is_Hidden (Prim_Op)
7196 and then not Is_Immediately_Visible (Obj_Type)
7197 and then not In_Instance
7198 and then not Is_Private_Overriding (Prim_Op))
7203 Set_Etype (Call_Node, Any_Type);
7204 Set_Is_Overloaded (Call_Node, False);
7206 if No (Matching_Op) then
7207 Prim_Op_Ref := New_Reference_To (Prim_Op, Sloc (Subprog));
7208 Candidate := Prim_Op;
7210 Set_Parent (Call_Node, Parent (Node_To_Replace));
7212 Set_Name (Call_Node, Prim_Op_Ref);
7218 Report => Report_Error,
7220 Skip_First => True);
7222 Matching_Op := Valid_Candidate (Success, Call_Node, Prim_Op);
7224 -- More than one interpretation, collect for subsequent
7225 -- disambiguation. If this is a procedure call and there
7226 -- is another match, report ambiguity now.
7232 Report => Report_Error,
7234 Skip_First => True);
7236 if Present (Valid_Candidate (Success, Call_Node, Prim_Op))
7237 and then Nkind (Call_Node) /= N_Function_Call
7239 Error_Msg_NE ("ambiguous call to&", N, Prim_Op);
7240 Report_Ambiguity (Matching_Op);
7241 Report_Ambiguity (Prim_Op);
7251 if Present (Matching_Op) then
7252 Set_Etype (Call_Node, Etype (Matching_Op));
7255 return Present (Matching_Op);
7256 end Try_Primitive_Operation;
7258 -- Start of processing for Try_Object_Operation
7261 Analyze_Expression (Obj);
7263 -- Analyze the actuals if node is known to be a subprogram call
7265 if Is_Subprg_Call and then N = Name (Parent (N)) then
7266 Actual := First (Parameter_Associations (Parent (N)));
7267 while Present (Actual) loop
7268 Analyze_Expression (Actual);
7273 -- Build a subprogram call node, using a copy of Obj as its first
7274 -- actual. This is a placeholder, to be replaced by an explicit
7275 -- dereference when needed.
7277 Transform_Object_Operation
7278 (Call_Node => New_Call_Node,
7279 Node_To_Replace => Node_To_Replace);
7281 Set_Etype (New_Call_Node, Any_Type);
7282 Set_Etype (Subprog, Any_Type);
7283 Set_Parent (New_Call_Node, Parent (Node_To_Replace));
7285 if not Is_Overloaded (Obj) then
7286 Try_One_Prefix_Interpretation (Obj_Type);
7293 Get_First_Interp (Obj, I, It);
7294 while Present (It.Nam) loop
7295 Try_One_Prefix_Interpretation (It.Typ);
7296 Get_Next_Interp (I, It);
7301 if Etype (New_Call_Node) /= Any_Type then
7302 Complete_Object_Operation
7303 (Call_Node => New_Call_Node,
7304 Node_To_Replace => Node_To_Replace);
7307 elsif Present (Candidate) then
7309 -- The argument list is not type correct. Re-analyze with error
7310 -- reporting enabled, and use one of the possible candidates.
7311 -- In All_Errors_Mode, re-analyze all failed interpretations.
7313 if All_Errors_Mode then
7314 Report_Error := True;
7315 if Try_Primitive_Operation
7316 (Call_Node => New_Call_Node,
7317 Node_To_Replace => Node_To_Replace)
7320 Try_Class_Wide_Operation
7321 (Call_Node => New_Call_Node,
7322 Node_To_Replace => Node_To_Replace)
7329 (N => New_Call_Node,
7333 Skip_First => True);
7336 -- No need for further errors
7341 -- There was no candidate operation, so report it as an error
7342 -- in the caller: Analyze_Selected_Component.
7346 end Try_Object_Operation;
7352 procedure wpo (T : Entity_Id) is
7357 if not Is_Tagged_Type (T) then
7361 E := First_Elmt (Primitive_Operations (Base_Type (T)));
7362 while Present (E) loop
7364 Write_Int (Int (Op));
7365 Write_Str (" === ");
7366 Write_Name (Chars (Op));
7368 Write_Name (Chars (Scope (Op)));