1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
10 -- Copyright (C) 1992-2002, Free Software Foundation, Inc. --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNAT; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- GNAT was originally developed by the GNAT team at New York University. --
24 -- Extensive contributions were provided by Ada Core Technologies Inc. --
26 ------------------------------------------------------------------------------
28 with Atree; use Atree;
29 with Checks; use Checks;
30 with Debug; use Debug;
31 with Einfo; use Einfo;
32 with Elists; use Elists;
33 with Errout; use Errout;
34 with Expander; use Expander;
35 with Exp_Ch7; use Exp_Ch7;
36 with Freeze; use Freeze;
37 with Lib.Xref; use Lib.Xref;
38 with Namet; use Namet;
40 with Nlists; use Nlists;
41 with Nmake; use Nmake;
43 with Output; use Output;
44 with Rtsfind; use Rtsfind;
46 with Sem_Cat; use Sem_Cat;
47 with Sem_Ch3; use Sem_Ch3;
48 with Sem_Ch4; use Sem_Ch4;
49 with Sem_Ch5; use Sem_Ch5;
50 with Sem_Ch8; use Sem_Ch8;
51 with Sem_Ch12; use Sem_Ch12;
52 with Sem_Disp; use Sem_Disp;
53 with Sem_Dist; use Sem_Dist;
54 with Sem_Elim; use Sem_Elim;
55 with Sem_Eval; use Sem_Eval;
56 with Sem_Mech; use Sem_Mech;
57 with Sem_Prag; use Sem_Prag;
58 with Sem_Res; use Sem_Res;
59 with Sem_Util; use Sem_Util;
60 with Sem_Type; use Sem_Type;
61 with Sem_Warn; use Sem_Warn;
62 with Sinput; use Sinput;
63 with Stand; use Stand;
64 with Sinfo; use Sinfo;
65 with Sinfo.CN; use Sinfo.CN;
66 with Snames; use Snames;
67 with Stringt; use Stringt;
69 with Stylesw; use Stylesw;
70 with Tbuild; use Tbuild;
71 with Uintp; use Uintp;
72 with Urealp; use Urealp;
73 with Validsw; use Validsw;
75 package body Sem_Ch6 is
77 -----------------------
78 -- Local Subprograms --
79 -----------------------
81 procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id);
82 -- Analyze a generic subprogram body
84 function Build_Body_To_Inline
89 -- If a subprogram has pragma Inline and inlining is active, use generic
90 -- machinery to build an unexpanded body for the subprogram. This body is
91 -- subsequenty used for inline expansions at call sites. If subprogram can
92 -- be inlined (depending on size and nature of local declarations) this
93 -- function returns true. Otherwise subprogram body is treated normally.
95 type Conformance_Type is
96 (Type_Conformant, Mode_Conformant, Subtype_Conformant, Fully_Conformant);
97 -- Conformance type used for following call, meaning matches the
98 -- RM definitions of the corresponding terms.
100 procedure Check_Conformance
103 Ctype : Conformance_Type;
105 Conforms : out Boolean;
106 Err_Loc : Node_Id := Empty;
107 Get_Inst : Boolean := False);
108 -- Given two entities, this procedure checks that the profiles associated
109 -- with these entities meet the conformance criterion given by the third
110 -- parameter. If they conform, Conforms is set True and control returns
111 -- to the caller. If they do not conform, Conforms is set to False, and
112 -- in addition, if Errmsg is True on the call, proper messages are output
113 -- to complain about the conformance failure. If Err_Loc is non_Empty
114 -- the error messages are placed on Err_Loc, if Err_Loc is empty, then
115 -- error messages are placed on the appropriate part of the construct
116 -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance
117 -- against a formal access-to-subprogram type so Get_Instance_Of must
120 procedure Check_Subprogram_Order (N : Node_Id);
121 -- N is the N_Subprogram_Body node for a subprogram. This routine applies
122 -- the alpha ordering rule for N if this ordering requirement applicable.
124 function Is_Non_Overriding_Operation
128 -- Enforce the rule given in 12.3(18): a private operation in an instance
129 -- overrides an inherited operation only if the corresponding operation
130 -- was overriding in the generic. This can happen for primitive operations
131 -- of types derived (in the generic unit) from formal private or formal
134 procedure Check_Returns
138 -- Called to check for missing return statements in a function body,
139 -- or for returns present in a procedure body which has No_Return set.
140 -- L is the handled statement sequence for the subprogram body. This
141 -- procedure checks all flow paths to make sure they either have a
142 -- return (Mode = 'F') or do not have a return (Mode = 'P'). The flag
143 -- Err is set if there are any control paths not explicitly terminated
144 -- by a return in the function case, and is True otherwise.
146 function Conforming_Types
149 Ctype : Conformance_Type;
150 Get_Inst : Boolean := False)
152 -- Check that two formal parameter types conform, checking both
153 -- for equality of base types, and where required statically
154 -- matching subtypes, depending on the setting of Ctype.
156 procedure Enter_Overloaded_Entity (S : Entity_Id);
157 -- This procedure makes S, a new overloaded entity, into the first
158 -- visible entity with that name.
160 procedure Install_Entity (E : Entity_Id);
161 -- Make single entity visible. Used for generic formals as well.
163 procedure Install_Formals (Id : Entity_Id);
164 -- On entry to a subprogram body, make the formals visible. Note
165 -- that simply placing the subprogram on the scope stack is not
166 -- sufficient: the formals must become the current entities for
169 procedure Make_Inequality_Operator (S : Entity_Id);
170 -- Create the declaration for an inequality operator that is implicitly
171 -- created by a user-defined equality operator that yields a boolean.
173 procedure May_Need_Actuals (Fun : Entity_Id);
174 -- Flag functions that can be called without parameters, i.e. those that
175 -- have no parameters, or those for which defaults exist for all parameters
177 procedure Set_Formal_Validity (Formal_Id : Entity_Id);
178 -- Formal_Id is an formal parameter entity. This procedure deals with
179 -- setting the proper validity status for this entity, which depends
180 -- on the kind of parameter and the validity checking mode.
182 ---------------------------------------------
183 -- Analyze_Abstract_Subprogram_Declaration --
184 ---------------------------------------------
186 procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is
187 Designator : constant Entity_Id := Analyze_Spec (Specification (N));
188 Scop : constant Entity_Id := Current_Scope;
191 Generate_Definition (Designator);
192 Set_Is_Abstract (Designator);
193 New_Overloaded_Entity (Designator);
194 Check_Delayed_Subprogram (Designator);
196 Set_Is_Pure (Designator,
197 Is_Pure (Scop) and then Is_Library_Level_Entity (Designator));
198 Set_Is_Remote_Call_Interface (
199 Designator, Is_Remote_Call_Interface (Scop));
200 Set_Is_Remote_Types (Designator, Is_Remote_Types (Scop));
202 if Ekind (Scope (Designator)) = E_Protected_Type then
204 ("abstract subprogram not allowed in protected type", N);
206 end Analyze_Abstract_Subprogram_Declaration;
208 ----------------------------
209 -- Analyze_Function_Call --
210 ----------------------------
212 procedure Analyze_Function_Call (N : Node_Id) is
213 P : constant Node_Id := Name (N);
214 L : constant List_Id := Parameter_Associations (N);
220 -- If error analyzing name, then set Any_Type as result type and return
222 if Etype (P) = Any_Type then
223 Set_Etype (N, Any_Type);
227 -- Otherwise analyze the parameters
232 while Present (Actual) loop
234 Check_Parameterless_Call (Actual);
241 end Analyze_Function_Call;
243 -------------------------------------
244 -- Analyze_Generic_Subprogram_Body --
245 -------------------------------------
247 procedure Analyze_Generic_Subprogram_Body
251 Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id);
253 Kind : constant Entity_Kind := Ekind (Gen_Id);
258 -- Copy body and disable expansion while analyzing the generic
259 -- For a stub, do not copy the stub (which would load the proper body),
260 -- this will be done when the proper body is analyzed.
262 if Nkind (N) /= N_Subprogram_Body_Stub then
263 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
268 Spec := Specification (N);
270 -- Within the body of the generic, the subprogram is callable, and
271 -- behaves like the corresponding non-generic unit.
273 Nam := Defining_Entity (Spec);
275 if Kind = E_Generic_Procedure
276 and then Nkind (Spec) /= N_Procedure_Specification
278 Error_Msg_N ("invalid body for generic procedure ", Nam);
281 elsif Kind = E_Generic_Function
282 and then Nkind (Spec) /= N_Function_Specification
284 Error_Msg_N ("invalid body for generic function ", Nam);
288 Set_Corresponding_Body (Gen_Decl, Nam);
290 if Has_Completion (Gen_Id)
291 and then Nkind (Parent (N)) /= N_Subunit
293 Error_Msg_N ("duplicate generic body", N);
296 Set_Has_Completion (Gen_Id);
299 if Nkind (N) = N_Subprogram_Body_Stub then
300 Set_Ekind (Defining_Entity (Specification (N)), Kind);
302 Set_Corresponding_Spec (N, Gen_Id);
305 if Nkind (Parent (N)) = N_Compilation_Unit then
306 Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N));
309 -- Make generic parameters immediately visible in the body. They are
310 -- needed to process the formals declarations. Then make the formals
311 -- visible in a separate step.
317 First_Ent : Entity_Id;
320 First_Ent := First_Entity (Gen_Id);
323 while Present (E) and then not Is_Formal (E) loop
328 Set_Use (Generic_Formal_Declarations (Gen_Decl));
330 -- Now generic formals are visible, and the specification can be
331 -- analyzed, for subsequent conformance check.
333 Nam := Analyze_Spec (Spec);
335 if Nkind (N) = N_Subprogram_Body_Stub then
337 -- Nothing to do if no body to process
339 Set_Ekind (Nam, Kind);
346 -- E is the first formal parameter, which must be the first
347 -- entity in the subprogram body.
349 Set_First_Entity (Gen_Id, E);
351 -- Now make formal parameters visible
353 while Present (E) loop
359 -- Visible generic entity is callable within its own body.
361 Set_Ekind (Gen_Id, Ekind (Nam));
362 Set_Convention (Nam, Convention (Gen_Id));
363 Set_Scope (Nam, Scope (Gen_Id));
364 Check_Fully_Conformant (Nam, Gen_Id, Nam);
366 -- If this is a compilation unit, it must be made visible
367 -- explicitly, because the compilation of the declaration,
368 -- unlike other library unit declarations, does not. If it
369 -- is not a unit, the following is redundant but harmless.
371 Set_Is_Immediately_Visible (Gen_Id);
373 Set_Actual_Subtypes (N, Current_Scope);
374 Analyze_Declarations (Declarations (N));
376 Analyze (Handled_Statement_Sequence (N));
378 Save_Global_References (Original_Node (N));
380 -- Prior to exiting the scope, include generic formals again
381 -- (if any are present) in the set of local entities.
383 if Present (First_Ent) then
384 Set_First_Entity (Gen_Id, First_Ent);
390 Check_Subprogram_Order (N);
392 -- Outside of its body, unit is generic again.
394 Set_Ekind (Gen_Id, Kind);
395 Set_Ekind (Nam, E_Subprogram_Body);
396 Generate_Reference (Gen_Id, Nam, 'b');
397 Style.Check_Identifier (Nam, Gen_Id);
400 end Analyze_Generic_Subprogram_Body;
402 -----------------------------
403 -- Analyze_Operator_Symbol --
404 -----------------------------
406 -- An operator symbol such as "+" or "and" may appear in context where
407 -- the literal denotes an entity name, such as "+"(x, y) or in a
408 -- context when it is just a string, as in (conjunction = "or"). In
409 -- these cases the parser generates this node, and the semantics does
410 -- the disambiguation. Other such case are actuals in an instantiation,
411 -- the generic unit in an instantiation, and pragma arguments.
413 procedure Analyze_Operator_Symbol (N : Node_Id) is
414 Par : constant Node_Id := Parent (N);
417 if (Nkind (Par) = N_Function_Call and then N = Name (Par))
418 or else Nkind (Par) = N_Function_Instantiation
419 or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par))
420 or else (Nkind (Par) = N_Pragma_Argument_Association
421 and then not Is_Pragma_String_Literal (Par))
422 or else Nkind (Par) = N_Subprogram_Renaming_Declaration
423 or else (Nkind (Par) = N_Attribute_Reference
424 and then Attribute_Name (Par) /= Name_Value)
426 Find_Direct_Name (N);
429 Change_Operator_Symbol_To_String_Literal (N);
432 end Analyze_Operator_Symbol;
434 -----------------------------------
435 -- Analyze_Parameter_Association --
436 -----------------------------------
438 procedure Analyze_Parameter_Association (N : Node_Id) is
440 Analyze (Explicit_Actual_Parameter (N));
441 end Analyze_Parameter_Association;
443 ----------------------------
444 -- Analyze_Procedure_Call --
445 ----------------------------
447 procedure Analyze_Procedure_Call (N : Node_Id) is
448 Loc : constant Source_Ptr := Sloc (N);
449 P : constant Node_Id := Name (N);
450 Actuals : constant List_Id := Parameter_Associations (N);
454 procedure Analyze_Call_And_Resolve;
455 -- Do Analyze and Resolve calls for procedure call
457 procedure Analyze_Call_And_Resolve is
459 if Nkind (N) = N_Procedure_Call_Statement then
461 Resolve (N, Standard_Void_Type);
465 end Analyze_Call_And_Resolve;
467 -- Start of processing for Analyze_Procedure_Call
470 -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote
471 -- a procedure call or an entry call. The prefix may denote an access
472 -- to subprogram type, in which case an implicit dereference applies.
473 -- If the prefix is an indexed component (without implicit defererence)
474 -- then the construct denotes a call to a member of an entire family.
475 -- If the prefix is a simple name, it may still denote a call to a
476 -- parameterless member of an entry family. Resolution of these various
477 -- interpretations is delicate.
481 -- If error analyzing prefix, then set Any_Type as result and return
483 if Etype (P) = Any_Type then
484 Set_Etype (N, Any_Type);
488 -- Otherwise analyze the parameters
490 if Present (Actuals) then
491 Actual := First (Actuals);
493 while Present (Actual) loop
495 Check_Parameterless_Call (Actual);
500 -- Special processing for Elab_Spec and Elab_Body calls
502 if Nkind (P) = N_Attribute_Reference
503 and then (Attribute_Name (P) = Name_Elab_Spec
504 or else Attribute_Name (P) = Name_Elab_Body)
506 if Present (Actuals) then
508 ("no parameters allowed for this call", First (Actuals));
512 Set_Etype (N, Standard_Void_Type);
515 elsif Is_Entity_Name (P)
516 and then Is_Record_Type (Etype (Entity (P)))
517 and then Remote_AST_I_Dereference (P)
521 elsif Is_Entity_Name (P)
522 and then Ekind (Entity (P)) /= E_Entry_Family
524 if Is_Access_Type (Etype (P))
525 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
526 and then No (Actuals)
527 and then Comes_From_Source (N)
529 Error_Msg_N ("missing explicit dereference in call", N);
532 Analyze_Call_And_Resolve;
534 -- If the prefix is the simple name of an entry family, this is
535 -- a parameterless call from within the task body itself.
537 elsif Is_Entity_Name (P)
538 and then Nkind (P) = N_Identifier
539 and then Ekind (Entity (P)) = E_Entry_Family
540 and then Present (Actuals)
541 and then No (Next (First (Actuals)))
543 -- Can be call to parameterless entry family. What appears to be
544 -- the sole argument is in fact the entry index. Rewrite prefix
545 -- of node accordingly. Source representation is unchanged by this
549 Make_Indexed_Component (Loc,
551 Make_Selected_Component (Loc,
552 Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc),
553 Selector_Name => New_Occurrence_Of (Entity (P), Loc)),
554 Expressions => Actuals);
556 Set_Etype (New_N, Standard_Void_Type);
557 Set_Parameter_Associations (N, No_List);
558 Analyze_Call_And_Resolve;
560 elsif Nkind (P) = N_Explicit_Dereference then
561 if Ekind (Etype (P)) = E_Subprogram_Type then
562 Analyze_Call_And_Resolve;
564 Error_Msg_N ("expect access to procedure in call", P);
567 -- The name can be a selected component or an indexed component
568 -- that yields an access to subprogram. Such a prefix is legal if
569 -- the call has parameter associations.
571 elsif Is_Access_Type (Etype (P))
572 and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type
574 if Present (Actuals) then
575 Analyze_Call_And_Resolve;
577 Error_Msg_N ("missing explicit dereference in call ", N);
580 -- If not an access to subprogram, then the prefix must resolve to
581 -- the name of an entry, entry family, or protected operation.
583 -- For the case of a simple entry call, P is a selected component
584 -- where the prefix is the task and the selector name is the entry.
585 -- A call to a protected procedure will have the same syntax. If
586 -- the protected object contains overloaded operations, the entity
587 -- may appear as a function, the context will select the operation
588 -- whose type is Void.
590 elsif Nkind (P) = N_Selected_Component
591 and then (Ekind (Entity (Selector_Name (P))) = E_Entry
593 Ekind (Entity (Selector_Name (P))) = E_Procedure
595 Ekind (Entity (Selector_Name (P))) = E_Function)
597 Analyze_Call_And_Resolve;
599 elsif Nkind (P) = N_Selected_Component
600 and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family
601 and then Present (Actuals)
602 and then No (Next (First (Actuals)))
604 -- Can be call to parameterless entry family. What appears to be
605 -- the sole argument is in fact the entry index. Rewrite prefix
606 -- of node accordingly. Source representation is unchanged by this
610 Make_Indexed_Component (Loc,
611 Prefix => New_Copy (P),
612 Expressions => Actuals);
614 Set_Etype (New_N, Standard_Void_Type);
615 Set_Parameter_Associations (N, No_List);
616 Analyze_Call_And_Resolve;
618 -- For the case of a reference to an element of an entry family, P is
619 -- an indexed component whose prefix is a selected component (task and
620 -- entry family), and whose index is the entry family index.
622 elsif Nkind (P) = N_Indexed_Component
623 and then Nkind (Prefix (P)) = N_Selected_Component
624 and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family
626 Analyze_Call_And_Resolve;
628 -- If the prefix is the name of an entry family, it is a call from
629 -- within the task body itself.
631 elsif Nkind (P) = N_Indexed_Component
632 and then Nkind (Prefix (P)) = N_Identifier
633 and then Ekind (Entity (Prefix (P))) = E_Entry_Family
636 Make_Selected_Component (Loc,
637 Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc),
638 Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc));
639 Rewrite (Prefix (P), New_N);
641 Analyze_Call_And_Resolve;
643 -- Anything else is an error.
646 Error_Msg_N ("Invalid procedure or entry call", N);
648 end Analyze_Procedure_Call;
650 ------------------------------
651 -- Analyze_Return_Statement --
652 ------------------------------
654 procedure Analyze_Return_Statement (N : Node_Id) is
655 Loc : constant Source_Ptr := Sloc (N);
657 Scope_Id : Entity_Id;
662 -- Find subprogram or accept statement enclosing the return statement
665 for J in reverse 0 .. Scope_Stack.Last loop
666 Scope_Id := Scope_Stack.Table (J).Entity;
667 exit when Ekind (Scope_Id) /= E_Block and then
668 Ekind (Scope_Id) /= E_Loop;
671 pragma Assert (Present (Scope_Id));
673 Kind := Ekind (Scope_Id);
674 Expr := Expression (N);
676 if Kind /= E_Function
677 and then Kind /= E_Generic_Function
678 and then Kind /= E_Procedure
679 and then Kind /= E_Generic_Procedure
680 and then Kind /= E_Entry
681 and then Kind /= E_Entry_Family
683 Error_Msg_N ("illegal context for return statement", N);
685 elsif Present (Expr) then
686 if Kind = E_Function or else Kind = E_Generic_Function then
687 Set_Return_Present (Scope_Id);
688 R_Type := Etype (Scope_Id);
689 Set_Return_Type (N, R_Type);
690 Analyze_And_Resolve (Expr, R_Type);
692 if (Is_Class_Wide_Type (Etype (Expr))
693 or else Is_Dynamically_Tagged (Expr))
694 and then not Is_Class_Wide_Type (R_Type)
697 ("dynamically tagged expression not allowed!", Expr);
700 Apply_Constraint_Check (Expr, R_Type);
702 -- ??? A real run-time accessibility check is needed
703 -- in cases involving dereferences of access parameters.
704 -- For now we just check the static cases.
706 if Is_Return_By_Reference_Type (Etype (Scope_Id))
707 and then Object_Access_Level (Expr)
708 > Subprogram_Access_Level (Scope_Id)
711 Make_Raise_Program_Error (Loc,
712 Reason => PE_Accessibility_Check_Failed));
716 ("cannot return a local value by reference?", N);
718 ("& will be raised at run time?!",
719 N, Standard_Program_Error);
722 elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then
723 Error_Msg_N ("procedure cannot return value (use function)", N);
726 Error_Msg_N ("accept statement cannot return value", N);
729 -- No expression present
732 if Kind = E_Function or Kind = E_Generic_Function then
733 Error_Msg_N ("missing expression in return from function", N);
736 if (Ekind (Scope_Id) = E_Procedure
737 or else Ekind (Scope_Id) = E_Generic_Procedure)
738 and then No_Return (Scope_Id)
741 ("RETURN statement not allowed (No_Return)", N);
745 Check_Unreachable_Code (N);
746 end Analyze_Return_Statement;
752 function Analyze_Spec (N : Node_Id) return Entity_Id is
753 Designator : constant Entity_Id := Defining_Entity (N);
754 Formals : constant List_Id := Parameter_Specifications (N);
758 Generate_Definition (Designator);
760 if Nkind (N) = N_Function_Specification then
761 Set_Ekind (Designator, E_Function);
762 Set_Mechanism (Designator, Default_Mechanism);
764 if Subtype_Mark (N) /= Error then
765 Find_Type (Subtype_Mark (N));
766 Typ := Entity (Subtype_Mark (N));
767 Set_Etype (Designator, Typ);
769 if (Ekind (Typ) = E_Incomplete_Type
770 or else (Is_Class_Wide_Type (Typ)
772 Ekind (Root_Type (Typ)) = E_Incomplete_Type))
775 ("invalid use of incomplete type", Subtype_Mark (N));
779 Set_Etype (Designator, Any_Type);
783 Set_Ekind (Designator, E_Procedure);
784 Set_Etype (Designator, Standard_Void_Type);
787 if Present (Formals) then
788 Set_Scope (Designator, Current_Scope);
789 New_Scope (Designator);
790 Process_Formals (Formals, N);
794 if Nkind (N) = N_Function_Specification then
795 if Nkind (Designator) = N_Defining_Operator_Symbol then
796 Valid_Operator_Definition (Designator);
799 May_Need_Actuals (Designator);
801 if Is_Abstract (Etype (Designator))
802 and then Nkind (Parent (N)) /= N_Abstract_Subprogram_Declaration
805 ("function that returns abstract type must be abstract", N);
812 -----------------------------
813 -- Analyze_Subprogram_Body --
814 -----------------------------
816 -- This procedure is called for regular subprogram bodies, generic bodies,
817 -- and for subprogram stubs of both kinds. In the case of stubs, only the
818 -- specification matters, and is used to create a proper declaration for
819 -- the subprogram, or to perform conformance checks.
821 procedure Analyze_Subprogram_Body (N : Node_Id) is
822 Loc : constant Source_Ptr := Sloc (N);
823 Body_Spec : constant Node_Id := Specification (N);
824 Body_Id : Entity_Id := Defining_Entity (Body_Spec);
825 Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id);
829 Spec_Decl : Node_Id := Empty;
830 Last_Formal : Entity_Id := Empty;
831 Conformant : Boolean;
832 Missing_Ret : Boolean;
833 Body_Deleted : Boolean := False;
838 Write_Str ("==== Compiling subprogram body ");
839 Write_Name (Chars (Body_Id));
840 Write_Str (" from ");
841 Write_Location (Loc);
845 Trace_Scope (N, Body_Id, " Analyze subprogram");
847 -- Generic subprograms are handled separately. They always have
848 -- a generic specification. Determine whether current scope has
849 -- a previous declaration.
851 -- If the subprogram body is defined within an instance of the
852 -- same name, the instance appears as a package renaming, and
853 -- will be hidden within the subprogram.
856 and then not Is_Overloadable (Prev_Id)
857 and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration
858 or else Comes_From_Source (Prev_Id))
860 if Ekind (Prev_Id) = E_Generic_Procedure
861 or else Ekind (Prev_Id) = E_Generic_Function
864 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
865 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
867 Analyze_Generic_Subprogram_Body (N, Spec_Id);
871 -- Previous entity conflicts with subprogram name.
872 -- Attempting to enter name will post error.
874 Enter_Name (Body_Id);
878 -- Non-generic case, find the subprogram declaration, if one was
879 -- seen, or enter new overloaded entity in the current scope.
880 -- If the current_entity is the body_id itself, the unit is being
881 -- analyzed as part of the context of one of its subunits. No need
882 -- to redo the analysis.
884 elsif Prev_Id = Body_Id
885 and then Has_Completion (Body_Id)
890 Body_Id := Analyze_Spec (Body_Spec);
892 if Nkind (N) = N_Subprogram_Body_Stub
893 or else No (Corresponding_Spec (N))
895 Spec_Id := Find_Corresponding_Spec (N);
897 -- If this is a duplicate body, no point in analyzing it
899 if Error_Posted (N) then
903 -- A subprogram body should cause freezing of its own
904 -- declaration, but if there was no previous explicit
905 -- declaration, then the subprogram will get frozen too
906 -- late (there may be code within the body that depends
907 -- on the subprogram having been frozen, such as uses of
908 -- extra formals), so we force it to be frozen here.
909 -- Same holds if the body and the spec are compilation units.
912 Freeze_Before (N, Body_Id);
914 elsif Nkind (Parent (N)) = N_Compilation_Unit then
915 Freeze_Before (N, Spec_Id);
918 Spec_Id := Corresponding_Spec (N);
922 -- Do not inline any subprogram that contains nested subprograms,
923 -- since the backend inlining circuit seems to generate uninitialized
924 -- references in this case. We know this happens in the case of front
925 -- end ZCX support, but it also appears it can happen in other cases
926 -- as well. The backend often rejects attempts to inline in the case
927 -- of nested procedures anyway, so little if anything is lost by this.
929 -- Do not do this test if errors have been detected, because in some
930 -- error cases, this code blows up, and we don't need it anyway if
931 -- there have been errors, since we won't get to the linker anyway.
933 if Serious_Errors_Detected = 0 then
936 P_Ent := Scope (P_Ent);
937 exit when No (P_Ent) or else P_Ent = Standard_Standard;
939 if Is_Subprogram (P_Ent) and then Is_Inlined (P_Ent) then
940 Set_Is_Inlined (P_Ent, False);
942 if Comes_From_Source (P_Ent)
943 and then Ineffective_Inline_Warnings
944 and then Has_Pragma_Inline (P_Ent)
947 ("?pragma Inline for & ignored (has nested subprogram)",
948 Get_Rep_Pragma (P_Ent, Name_Inline), P_Ent);
954 -- Case of fully private operation in the body of the protected type.
955 -- We must create a declaration for the subprogram, in order to attach
956 -- the protected subprogram that will be used in internal calls.
959 and then Comes_From_Source (N)
960 and then Is_Protected_Type (Current_Scope)
969 Formal := First_Formal (Body_Id);
971 -- The protected operation always has at least one formal,
972 -- namely the object itself, but it is only placed in the
973 -- parameter list if expansion is enabled.
976 or else Expander_Active
984 while Present (Formal) loop
986 (Make_Parameter_Specification (Loc,
987 Defining_Identifier =>
988 Make_Defining_Identifier (Sloc (Formal),
989 Chars => Chars (Formal)),
990 In_Present => In_Present (Parent (Formal)),
991 Out_Present => Out_Present (Parent (Formal)),
993 New_Reference_To (Etype (Formal), Loc),
995 New_Copy_Tree (Expression (Parent (Formal)))),
998 Next_Formal (Formal);
1001 if Nkind (Body_Spec) = N_Procedure_Specification then
1003 Make_Procedure_Specification (Loc,
1004 Defining_Unit_Name =>
1005 Make_Defining_Identifier (Sloc (Body_Id),
1006 Chars => Chars (Body_Id)),
1007 Parameter_Specifications => Plist);
1010 Make_Function_Specification (Loc,
1011 Defining_Unit_Name =>
1012 Make_Defining_Identifier (Sloc (Body_Id),
1013 Chars => Chars (Body_Id)),
1014 Parameter_Specifications => Plist,
1015 Subtype_Mark => New_Occurrence_Of (Etype (Body_Id), Loc));
1019 Make_Subprogram_Declaration (Loc,
1020 Specification => New_Spec);
1021 Insert_Before (N, Decl);
1023 Spec_Id := Defining_Unit_Name (New_Spec);
1024 Set_Has_Completion (Spec_Id);
1025 Set_Convention (Spec_Id, Convention_Protected);
1028 elsif Present (Spec_Id) then
1029 Spec_Decl := Unit_Declaration_Node (Spec_Id);
1032 -- Place subprogram on scope stack, and make formals visible. If there
1033 -- is a spec, the visible entity remains that of the spec.
1035 if Present (Spec_Id) then
1036 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
1037 Style.Check_Identifier (Body_Id, Spec_Id);
1039 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
1040 Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id));
1042 if Is_Abstract (Spec_Id) then
1043 Error_Msg_N ("an abstract subprogram cannot have a body", N);
1046 Set_Convention (Body_Id, Convention (Spec_Id));
1047 Set_Has_Completion (Spec_Id);
1049 if Is_Protected_Type (Scope (Spec_Id)) then
1050 Set_Privals_Chain (Spec_Id, New_Elmt_List);
1053 -- If this is a body generated for a renaming, do not check for
1054 -- full conformance. The check is redundant, because the spec of
1055 -- the body is a copy of the spec in the renaming declaration,
1056 -- and the test can lead to spurious errors on nested defaults.
1058 if Present (Spec_Decl)
1059 and then not Comes_From_Source (N)
1061 (Nkind (Original_Node (Spec_Decl)) =
1062 N_Subprogram_Renaming_Declaration
1063 or else (Present (Corresponding_Body (Spec_Decl))
1065 Nkind (Unit_Declaration_Node
1066 (Corresponding_Body (Spec_Decl))) =
1067 N_Subprogram_Renaming_Declaration))
1073 Fully_Conformant, True, Conformant, Body_Id);
1076 -- If the body is not fully conformant, we have to decide if we
1077 -- should analyze it or not. If it has a really messed up profile
1078 -- then we probably should not analyze it, since we will get too
1079 -- many bogus messages.
1081 -- Our decision is to go ahead in the non-fully conformant case
1082 -- only if it is at least mode conformant with the spec. Note
1083 -- that the call to Check_Fully_Conformant has issued the proper
1084 -- error messages to complain about the lack of conformance.
1087 and then not Mode_Conformant (Body_Id, Spec_Id)
1093 -- Generate references from body formals to spec formals
1094 -- and also set the Spec_Entity fields for all formals. We
1095 -- do not set this reference count as a reference for the
1096 -- purposes of identifying unreferenced formals however.
1098 if Spec_Id /= Body_Id then
1104 Fs := First_Formal (Spec_Id);
1105 Fb := First_Formal (Body_Id);
1106 while Present (Fs) loop
1107 Generate_Reference (Fs, Fb, 'b');
1108 Style.Check_Identifier (Fb, Fs);
1109 Set_Spec_Entity (Fb, Fs);
1110 Set_Referenced (Fs, False);
1117 if Nkind (N) /= N_Subprogram_Body_Stub then
1118 Set_Corresponding_Spec (N, Spec_Id);
1119 Install_Formals (Spec_Id);
1120 Last_Formal := Last_Entity (Spec_Id);
1121 New_Scope (Spec_Id);
1123 -- Make sure that the subprogram is immediately visible. For
1124 -- child units that have no separate spec this is indispensable.
1125 -- Otherwise it is safe albeit redundant.
1127 Set_Is_Immediately_Visible (Spec_Id);
1130 Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id);
1131 Set_Ekind (Body_Id, E_Subprogram_Body);
1132 Set_Scope (Body_Id, Scope (Spec_Id));
1134 -- Case of subprogram body with no previous spec
1138 and then Comes_From_Source (Body_Id)
1139 and then not Suppress_Style_Checks (Body_Id)
1140 and then not In_Instance
1142 Style.Body_With_No_Spec (N);
1145 New_Overloaded_Entity (Body_Id);
1147 if Nkind (N) /= N_Subprogram_Body_Stub then
1148 Set_Acts_As_Spec (N);
1149 Generate_Definition (Body_Id);
1150 Install_Formals (Body_Id);
1151 New_Scope (Body_Id);
1155 -- If this is the proper body of a stub, we must verify that the stub
1156 -- conforms to the body, and to the previous spec if one was present.
1157 -- we know already that the body conforms to that spec. This test is
1158 -- only required for subprograms that come from source.
1160 if Nkind (Parent (N)) = N_Subunit
1161 and then Comes_From_Source (N)
1162 and then not Error_Posted (Body_Id)
1165 Conformant : Boolean := False;
1166 Old_Id : Entity_Id :=
1168 (Specification (Corresponding_Stub (Parent (N))));
1171 if No (Spec_Id) then
1172 Check_Fully_Conformant (Body_Id, Old_Id);
1176 (Body_Id, Old_Id, Fully_Conformant, False, Conformant);
1178 if not Conformant then
1180 -- The stub was taken to be a new declaration. Indicate
1181 -- that it lacks a body.
1183 Set_Has_Completion (Old_Id, False);
1189 Set_Has_Completion (Body_Id);
1190 Check_Eliminated (Body_Id);
1192 if Nkind (N) = N_Subprogram_Body_Stub then
1195 elsif Present (Spec_Id)
1196 and then Expander_Active
1197 and then (Is_Always_Inlined (Spec_Id)
1198 or else (Has_Pragma_Inline (Spec_Id)
1200 (Front_End_Inlining or else No_Run_Time)))
1202 if Build_Body_To_Inline (N, Spec_Id, Copy_Separate_Tree (N)) then
1207 -- Now we can go on to analyze the body
1209 HSS := Handled_Statement_Sequence (N);
1210 Set_Actual_Subtypes (N, Current_Scope);
1211 Analyze_Declarations (Declarations (N));
1214 Process_End_Label (HSS, 't', Current_Scope);
1216 Check_Subprogram_Order (N);
1218 -- If we have a separate spec, then the analysis of the declarations
1219 -- caused the entities in the body to be chained to the spec id, but
1220 -- we want them chained to the body id. Only the formal parameters
1221 -- end up chained to the spec id in this case.
1223 if Present (Spec_Id) then
1225 -- If a parent unit is categorized, the context of a subunit
1226 -- must conform to the categorization. Conversely, if a child
1227 -- unit is categorized, the parents themselves must conform.
1229 if Nkind (Parent (N)) = N_Subunit then
1230 Validate_Categorization_Dependency (N, Spec_Id);
1232 elsif Is_Child_Unit (Spec_Id) then
1233 Validate_Categorization_Dependency
1234 (Unit_Declaration_Node (Spec_Id), Spec_Id);
1237 if Present (Last_Formal) then
1239 (Last_Entity (Body_Id), Next_Entity (Last_Formal));
1240 Set_Next_Entity (Last_Formal, Empty);
1241 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1242 Set_Last_Entity (Spec_Id, Last_Formal);
1245 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
1246 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
1247 Set_First_Entity (Spec_Id, Empty);
1248 Set_Last_Entity (Spec_Id, Empty);
1252 -- If function, check return statements
1254 if Nkind (Body_Spec) = N_Function_Specification then
1259 if Present (Spec_Id) then
1265 if Return_Present (Id) then
1266 Check_Returns (HSS, 'F', Missing_Ret);
1269 Set_Has_Missing_Return (Id);
1272 elsif not Is_Machine_Code_Subprogram (Id)
1273 and then not Body_Deleted
1275 Error_Msg_N ("missing RETURN statement in function body", N);
1279 -- If procedure with No_Return, check returns
1281 elsif Nkind (Body_Spec) = N_Procedure_Specification
1282 and then Present (Spec_Id)
1283 and then No_Return (Spec_Id)
1285 Check_Returns (HSS, 'P', Missing_Ret);
1288 -- Don't worry about checking for variables that are never modified
1289 -- if the first statement of the body is a raise statement, since
1290 -- we assume this is some kind of stub. We ignore a label generated
1291 -- by the exception stuff for the purpose of this test.
1294 Stm : Node_Id := First (Statements (HSS));
1297 if Nkind (Stm) = N_Label then
1301 if Nkind (Original_Node (Stm)) = N_Raise_Statement then
1306 -- Check for variables that are never modified
1312 -- If there is a separate spec, then transfer Not_Source_Assigned
1313 -- flags from out parameters to the corresponding entities in the
1314 -- body. The reason we do that is we want to post error flags on
1315 -- the body entities, not the spec entities.
1317 if Present (Spec_Id) then
1318 E1 := First_Entity (Spec_Id);
1320 while Present (E1) loop
1321 if Ekind (E1) = E_Out_Parameter then
1322 E2 := First_Entity (Body_Id);
1325 -- If no matching body entity, then we already had
1326 -- a detected error of some kind, so just forget
1327 -- about worrying about these warnings.
1333 exit when Chars (E1) = Chars (E2);
1337 Set_Not_Source_Assigned (E2, Not_Source_Assigned (E1));
1344 -- Check references in body unless it was deleted. Note that the
1345 -- check of Body_Deleted here is not just for efficiency, it is
1346 -- necessary to avoid junk warnings on formal parameters.
1348 if not Body_Deleted then
1349 Check_References (Body_Id);
1352 end Analyze_Subprogram_Body;
1354 ------------------------------------
1355 -- Analyze_Subprogram_Declaration --
1356 ------------------------------------
1358 procedure Analyze_Subprogram_Declaration (N : Node_Id) is
1359 Designator : constant Entity_Id := Analyze_Spec (Specification (N));
1360 Scop : constant Entity_Id := Current_Scope;
1362 -- Start of processing for Analyze_Subprogram_Declaration
1365 Generate_Definition (Designator);
1367 -- Check for RCI unit subprogram declarations against in-lined
1368 -- subprograms and subprograms having access parameter or limited
1369 -- parameter without Read and Write (RM E.2.3(12-13)).
1371 Validate_RCI_Subprogram_Declaration (N);
1375 Defining_Entity (N),
1376 " Analyze subprogram spec. ");
1378 if Debug_Flag_C then
1379 Write_Str ("==== Compiling subprogram spec ");
1380 Write_Name (Chars (Designator));
1381 Write_Str (" from ");
1382 Write_Location (Sloc (N));
1386 New_Overloaded_Entity (Designator);
1387 Check_Delayed_Subprogram (Designator);
1388 Set_Suppress_Elaboration_Checks
1389 (Designator, Elaboration_Checks_Suppressed (Designator));
1391 if Scop /= Standard_Standard
1392 and then not Is_Child_Unit (Designator)
1394 Set_Is_Pure (Designator,
1395 Is_Pure (Scop) and then Is_Library_Level_Entity (Designator));
1396 Set_Is_Remote_Call_Interface (
1397 Designator, Is_Remote_Call_Interface (Scop));
1398 Set_Is_Remote_Types (Designator, Is_Remote_Types (Scop));
1401 -- For a compilation unit, check for library-unit pragmas.
1403 New_Scope (Designator);
1404 Set_Categorization_From_Pragmas (N);
1405 Validate_Categorization_Dependency (N, Designator);
1409 -- For a compilation unit, set body required. This flag will only be
1410 -- reset if a valid Import or Interface pragma is processed later on.
1412 if Nkind (Parent (N)) = N_Compilation_Unit then
1413 Set_Body_Required (Parent (N), True);
1416 Check_Eliminated (Designator);
1417 end Analyze_Subprogram_Declaration;
1419 --------------------------
1420 -- Build_Body_To_Inline --
1421 --------------------------
1423 function Build_Body_To_Inline
1426 Orig_Body : Node_Id) return Boolean
1428 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
1429 Original_Body : Node_Id;
1430 Body_To_Analyze : Node_Id;
1431 Max_Size : constant := 10;
1432 Stat_Count : Integer := 0;
1434 function Has_Excluded_Declaration (Decls : List_Id) return Boolean;
1435 -- Check for declarations that make inlining not worthwhile.
1437 function Has_Excluded_Statement (Stats : List_Id) return Boolean;
1438 -- Check for statements that make inlining not worthwhile: any
1439 -- tasking statement, nested at any level. Keep track of total
1440 -- number of elementary statements, as a measure of acceptable size.
1442 function Has_Pending_Instantiation return Boolean;
1443 -- If some enclosing body contains instantiations that appear before
1444 -- the corresponding generic body, the enclosing body has a freeze node
1445 -- so that it can be elaborated after the generic itself. This might
1446 -- conflict with subsequent inlinings, so that it is unsafe to try to
1447 -- inline in such a case.
1453 procedure Cannot_Inline (Msg : String; N : Node_Id);
1454 -- If subprogram has pragma Inline_Always, it is an error if
1455 -- it cannot be inlined. Otherwise, emit a warning.
1457 procedure Cannot_Inline (Msg : String; N : Node_Id) is
1459 if Is_Always_Inlined (Subp) then
1460 Error_Msg_NE (Msg (1 .. Msg'Length - 1), N, Subp);
1462 elsif Ineffective_Inline_Warnings then
1463 Error_Msg_NE (Msg, N, Subp);
1467 ------------------------------
1468 -- Has_Excluded_Declaration --
1469 ------------------------------
1471 function Has_Excluded_Declaration (Decls : List_Id) return Boolean is
1477 while Present (D) loop
1478 if Nkind (D) = N_Function_Instantiation
1479 or else Nkind (D) = N_Protected_Type_Declaration
1480 or else Nkind (D) = N_Package_Declaration
1481 or else Nkind (D) = N_Package_Instantiation
1482 or else Nkind (D) = N_Subprogram_Body
1483 or else Nkind (D) = N_Procedure_Instantiation
1484 or else Nkind (D) = N_Task_Type_Declaration
1487 ("\declaration prevents front-end inlining of&?", D);
1496 end Has_Excluded_Declaration;
1498 ----------------------------
1499 -- Has_Excluded_Statement --
1500 ----------------------------
1502 function Has_Excluded_Statement (Stats : List_Id) return Boolean is
1509 while Present (S) loop
1510 Stat_Count := Stat_Count + 1;
1512 if Nkind (S) = N_Abort_Statement
1513 or else Nkind (S) = N_Asynchronous_Select
1514 or else Nkind (S) = N_Conditional_Entry_Call
1515 or else Nkind (S) = N_Delay_Relative_Statement
1516 or else Nkind (S) = N_Delay_Until_Statement
1517 or else Nkind (S) = N_Selective_Accept
1518 or else Nkind (S) = N_Timed_Entry_Call
1521 ("\statement prevents front-end inlining of&?", S);
1524 elsif Nkind (S) = N_Block_Statement then
1525 if Present (Declarations (S))
1526 and then Has_Excluded_Declaration (Declarations (S))
1530 elsif Present (Handled_Statement_Sequence (S))
1533 (Exception_Handlers (Handled_Statement_Sequence (S)))
1535 Has_Excluded_Statement
1536 (Statements (Handled_Statement_Sequence (S))))
1541 elsif Nkind (S) = N_Case_Statement then
1542 E := First (Alternatives (S));
1544 while Present (E) loop
1545 if Has_Excluded_Statement (Statements (E)) then
1552 elsif Nkind (S) = N_If_Statement then
1553 if Has_Excluded_Statement (Then_Statements (S)) then
1557 if Present (Elsif_Parts (S)) then
1558 E := First (Elsif_Parts (S));
1560 while Present (E) loop
1561 if Has_Excluded_Statement (Then_Statements (E)) then
1568 if Present (Else_Statements (S))
1569 and then Has_Excluded_Statement (Else_Statements (S))
1574 elsif Nkind (S) = N_Loop_Statement
1575 and then Has_Excluded_Statement (Statements (S))
1584 end Has_Excluded_Statement;
1586 -------------------------------
1587 -- Has_Pending_Instantiation --
1588 -------------------------------
1590 function Has_Pending_Instantiation return Boolean is
1591 S : Entity_Id := Current_Scope;
1594 while Present (S) loop
1595 if Is_Compilation_Unit (S)
1596 or else Is_Child_Unit (S)
1599 elsif Ekind (S) = E_Package
1600 and then Has_Forward_Instantiation (S)
1609 end Has_Pending_Instantiation;
1611 -- Start of processing for Build_Body_To_Inline
1614 if Nkind (Decl) = N_Subprogram_Declaration
1615 and then Present (Body_To_Inline (Decl))
1617 return True; -- Done already.
1619 -- Functions that return unconstrained composite types will require
1620 -- secondary stack handling, and cannot currently be inlined.
1622 elsif Ekind (Subp) = E_Function
1623 and then not Is_Scalar_Type (Etype (Subp))
1624 and then not Is_Access_Type (Etype (Subp))
1625 and then not Is_Constrained (Etype (Subp))
1628 ("unconstrained return type prevents front-end inlining of&?", N);
1632 -- We need to capture references to the formals in order to substitute
1633 -- the actuals at the point of inlining, i.e. instantiation. To treat
1634 -- the formals as globals to the body to inline, we nest it within
1635 -- a dummy parameterless subprogram, declared within the real one.
1637 Original_Body := Orig_Body;
1639 -- Within an instance, the current tree is already the result of
1640 -- a generic copy, and not what we need for subsequent inlining.
1641 -- We create the required body by doing an instantiating copy, to
1642 -- obtain the proper partially analyzed tree.
1645 if No (Generic_Parent (Specification (N))) then
1648 elsif Is_Child_Unit (Scope (Current_Scope)) then
1651 elsif Scope (Current_Scope) = Cunit_Entity (Main_Unit) then
1653 -- compiling an instantiation. There is no point in generating
1654 -- bodies to inline, because they will not be used.
1661 (Generic_Parent (Specification (N)), Empty,
1662 Instantiating => True);
1666 Copy_Generic_Node (Original_Body, Empty,
1667 Instantiating => False);
1670 Set_Parameter_Specifications (Specification (Original_Body), No_List);
1671 Set_Defining_Unit_Name (Specification (Original_Body),
1672 Make_Defining_Identifier (Sloc (N), New_Internal_Name ('S')));
1673 Set_Corresponding_Spec (Original_Body, Empty);
1675 if Ekind (Subp) = E_Function then
1676 Set_Subtype_Mark (Specification (Original_Body),
1677 New_Occurrence_Of (Etype (Subp), Sloc (N)));
1680 if Present (Declarations (Orig_Body))
1681 and then Has_Excluded_Declaration (Declarations (Orig_Body))
1686 if Present (Handled_Statement_Sequence (N)) then
1688 (Present (Exception_Handlers (Handled_Statement_Sequence (N))))
1690 Cannot_Inline ("handler prevents front-end inlining of&?",
1691 First (Exception_Handlers (Handled_Statement_Sequence (N))));
1694 Has_Excluded_Statement
1695 (Statements (Handled_Statement_Sequence (N)))
1701 -- We do not inline a subprogram that is too large, unless it is
1702 -- marked Inline_Always. This pragma does not suppress the other
1703 -- checks on inlining (forbidden declarations, handlers, etc).
1705 if Stat_Count > Max_Size
1706 and then not Is_Always_Inlined (Subp)
1708 Cannot_Inline ("body is too large for front-end inlining of&?", N);
1712 if Has_Pending_Instantiation then
1714 ("cannot inline& because of forward instance within enclosing body",
1719 Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False);
1721 -- Set return type of function, which is also global and does not need
1724 if Ekind (Subp) = E_Function then
1725 Set_Subtype_Mark (Specification (Body_To_Analyze),
1726 New_Occurrence_Of (Etype (Subp), Sloc (N)));
1729 if No (Declarations (N)) then
1730 Set_Declarations (N, New_List (Body_To_Analyze));
1732 Append (Body_To_Analyze, Declarations (N));
1735 Expander_Mode_Save_And_Set (False);
1737 Analyze (Body_To_Analyze);
1738 New_Scope (Defining_Entity (Body_To_Analyze));
1739 Save_Global_References (Original_Body);
1741 Remove (Body_To_Analyze);
1743 Expander_Mode_Restore;
1744 Set_Body_To_Inline (Decl, Original_Body);
1745 Set_Is_Inlined (Subp);
1748 end Build_Body_To_Inline;
1750 -----------------------
1751 -- Check_Conformance --
1752 -----------------------
1754 procedure Check_Conformance
1755 (New_Id : Entity_Id;
1757 Ctype : Conformance_Type;
1759 Conforms : out Boolean;
1760 Err_Loc : Node_Id := Empty;
1761 Get_Inst : Boolean := False)
1763 Old_Type : constant Entity_Id := Etype (Old_Id);
1764 New_Type : constant Entity_Id := Etype (New_Id);
1765 Old_Formal : Entity_Id;
1766 New_Formal : Entity_Id;
1768 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id);
1769 -- Post error message for conformance error on given node.
1770 -- Two messages are output. The first points to the previous
1771 -- declaration with a general "no conformance" message.
1772 -- The second is the detailed reason, supplied as Msg. The
1773 -- parameter N provide information for a possible & insertion
1774 -- in the message, and also provides the location for posting
1775 -- the message in the absence of a specified Err_Loc location.
1777 -----------------------
1778 -- Conformance_Error --
1779 -----------------------
1781 procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is
1788 if No (Err_Loc) then
1794 Error_Msg_Sloc := Sloc (Old_Id);
1797 when Type_Conformant =>
1799 ("not type conformant with declaration#!", Enode);
1801 when Mode_Conformant =>
1803 ("not mode conformant with declaration#!", Enode);
1805 when Subtype_Conformant =>
1807 ("not subtype conformant with declaration#!", Enode);
1809 when Fully_Conformant =>
1811 ("not fully conformant with declaration#!", Enode);
1814 Error_Msg_NE (Msg, Enode, N);
1816 end Conformance_Error;
1818 -- Start of processing for Check_Conformance
1823 -- We need a special case for operators, since they don't
1824 -- appear explicitly.
1826 if Ctype = Type_Conformant then
1827 if Ekind (New_Id) = E_Operator
1828 and then Operator_Matches_Spec (New_Id, Old_Id)
1834 -- If both are functions/operators, check return types conform
1836 if Old_Type /= Standard_Void_Type
1837 and then New_Type /= Standard_Void_Type
1839 if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then
1840 Conformance_Error ("return type does not match!", New_Id);
1844 -- If either is a function/operator and the other isn't, error
1846 elsif Old_Type /= Standard_Void_Type
1847 or else New_Type /= Standard_Void_Type
1849 Conformance_Error ("functions can only match functions!", New_Id);
1853 -- In subtype conformant case, conventions must match (RM 6.3.1(16))
1854 -- If this is a renaming as body, refine error message to indicate that
1855 -- the conflict is with the original declaration. If the entity is not
1856 -- frozen, the conventions don't have to match, the one of the renamed
1857 -- entity is inherited.
1859 if Ctype >= Subtype_Conformant then
1861 if Convention (Old_Id) /= Convention (New_Id) then
1863 if not Is_Frozen (New_Id) then
1866 elsif Present (Err_Loc)
1867 and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration
1868 and then Present (Corresponding_Spec (Err_Loc))
1870 Error_Msg_Name_1 := Chars (New_Id);
1872 Name_Ada + Convention_Id'Pos (Convention (New_Id));
1874 Conformance_Error ("prior declaration for% has convention %!");
1877 Conformance_Error ("calling conventions do not match!");
1882 elsif Is_Formal_Subprogram (Old_Id)
1883 or else Is_Formal_Subprogram (New_Id)
1885 Conformance_Error ("formal subprograms not allowed!");
1890 -- Deal with parameters
1892 -- Note: we use the entity information, rather than going directly
1893 -- to the specification in the tree. This is not only simpler, but
1894 -- absolutely necessary for some cases of conformance tests between
1895 -- operators, where the declaration tree simply does not exist!
1897 Old_Formal := First_Formal (Old_Id);
1898 New_Formal := First_Formal (New_Id);
1900 while Present (Old_Formal) and then Present (New_Formal) loop
1902 -- Types must always match. In the visible part of an instance,
1903 -- usual overloading rules for dispatching operations apply, and
1904 -- we check base types (not the actual subtypes).
1906 if In_Instance_Visible_Part
1907 and then Is_Dispatching_Operation (New_Id)
1909 if not Conforming_Types
1910 (Base_Type (Etype (Old_Formal)),
1911 Base_Type (Etype (New_Formal)), Ctype, Get_Inst)
1913 Conformance_Error ("type of & does not match!", New_Formal);
1917 elsif not Conforming_Types
1918 (Etype (Old_Formal), Etype (New_Formal), Ctype, Get_Inst)
1920 Conformance_Error ("type of & does not match!", New_Formal);
1924 -- For mode conformance, mode must match
1926 if Ctype >= Mode_Conformant
1927 and then Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal)
1929 Conformance_Error ("mode of & does not match!", New_Formal);
1933 -- Full conformance checks
1935 if Ctype = Fully_Conformant then
1939 if Chars (Old_Formal) /= Chars (New_Formal) then
1940 Conformance_Error ("name & does not match!", New_Formal);
1943 -- And default expressions for in parameters
1945 elsif Parameter_Mode (Old_Formal) = E_In_Parameter then
1947 NewD : constant Boolean :=
1948 Present (Default_Value (New_Formal));
1949 OldD : constant Boolean :=
1950 Present (Default_Value (Old_Formal));
1952 if NewD or OldD then
1954 -- The old default value has been analyzed and expanded,
1955 -- because the current full declaration will have frozen
1956 -- everything before. The new default values have not
1957 -- been expanded, so expand now to check conformance.
1961 Analyze_Default_Expression
1962 (Default_Value (New_Formal), Etype (New_Formal));
1966 if not (NewD and OldD)
1967 or else not Fully_Conformant_Expressions
1968 (Default_Value (Old_Formal),
1969 Default_Value (New_Formal))
1972 ("default expression for & does not match!",
1981 -- A couple of special checks for Ada 83 mode. These checks are
1982 -- skipped if either entity is an operator in package Standard.
1983 -- or if either old or new instance is not from the source program.
1986 and then Sloc (Old_Id) > Standard_Location
1987 and then Sloc (New_Id) > Standard_Location
1988 and then Comes_From_Source (Old_Id)
1989 and then Comes_From_Source (New_Id)
1992 Old_Param : constant Node_Id := Declaration_Node (Old_Formal);
1993 New_Param : constant Node_Id := Declaration_Node (New_Formal);
1996 -- Explicit IN must be present or absent in both cases. This
1997 -- test is required only in the full conformance case.
1999 if In_Present (Old_Param) /= In_Present (New_Param)
2000 and then Ctype = Fully_Conformant
2003 ("(Ada 83) IN must appear in both declarations",
2008 -- Grouping (use of comma in param lists) must be the same
2009 -- This is where we catch a misconformance like:
2012 -- A : Integer; B : Integer
2014 -- which are represented identically in the tree except
2015 -- for the setting of the flags More_Ids and Prev_Ids.
2017 if More_Ids (Old_Param) /= More_Ids (New_Param)
2018 or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param)
2021 ("grouping of & does not match!", New_Formal);
2027 Next_Formal (Old_Formal);
2028 Next_Formal (New_Formal);
2031 if Present (Old_Formal) then
2032 Conformance_Error ("too few parameters!");
2035 elsif Present (New_Formal) then
2036 Conformance_Error ("too many parameters!", New_Formal);
2040 end Check_Conformance;
2042 ------------------------------
2043 -- Check_Delayed_Subprogram --
2044 ------------------------------
2046 procedure Check_Delayed_Subprogram (Designator : Entity_Id) is
2049 procedure Possible_Freeze (T : Entity_Id);
2050 -- T is the type of either a formal parameter or of the return type.
2051 -- If T is not yet frozen and needs a delayed freeze, then the
2052 -- subprogram itself must be delayed.
2054 procedure Possible_Freeze (T : Entity_Id) is
2056 if Has_Delayed_Freeze (T)
2057 and then not Is_Frozen (T)
2059 Set_Has_Delayed_Freeze (Designator);
2061 elsif Is_Access_Type (T)
2062 and then Has_Delayed_Freeze (Designated_Type (T))
2063 and then not Is_Frozen (Designated_Type (T))
2065 Set_Has_Delayed_Freeze (Designator);
2067 end Possible_Freeze;
2069 -- Start of processing for Check_Delayed_Subprogram
2072 -- Never need to freeze abstract subprogram
2074 if Is_Abstract (Designator) then
2077 -- Need delayed freeze if return type itself needs a delayed
2078 -- freeze and is not yet frozen.
2080 Possible_Freeze (Etype (Designator));
2081 Possible_Freeze (Base_Type (Etype (Designator))); -- needed ???
2083 -- Need delayed freeze if any of the formal types themselves need
2084 -- a delayed freeze and are not yet frozen.
2086 F := First_Formal (Designator);
2087 while Present (F) loop
2088 Possible_Freeze (Etype (F));
2089 Possible_Freeze (Base_Type (Etype (F))); -- needed ???
2094 -- Mark functions that return by reference. Note that it cannot be
2095 -- done for delayed_freeze subprograms because the underlying
2096 -- returned type may not be known yet (for private types)
2098 if not Has_Delayed_Freeze (Designator)
2099 and then Expander_Active
2102 Typ : constant Entity_Id := Etype (Designator);
2103 Utyp : constant Entity_Id := Underlying_Type (Typ);
2106 if Is_Return_By_Reference_Type (Typ) then
2107 Set_Returns_By_Ref (Designator);
2109 elsif Present (Utyp) and then Controlled_Type (Utyp) then
2110 Set_Returns_By_Ref (Designator);
2114 end Check_Delayed_Subprogram;
2116 ------------------------------------
2117 -- Check_Discriminant_Conformance --
2118 ------------------------------------
2120 procedure Check_Discriminant_Conformance
2125 Old_Discr : Entity_Id := First_Discriminant (Prev);
2126 New_Discr : Node_Id := First (Discriminant_Specifications (N));
2127 New_Discr_Id : Entity_Id;
2128 New_Discr_Type : Entity_Id;
2130 procedure Conformance_Error (Msg : String; N : Node_Id);
2131 -- Post error message for conformance error on given node.
2132 -- Two messages are output. The first points to the previous
2133 -- declaration with a general "no conformance" message.
2134 -- The second is the detailed reason, supplied as Msg. The
2135 -- parameter N provide information for a possible & insertion
2138 -----------------------
2139 -- Conformance_Error --
2140 -----------------------
2142 procedure Conformance_Error (Msg : String; N : Node_Id) is
2144 Error_Msg_Sloc := Sloc (Prev_Loc);
2145 Error_Msg_N ("not fully conformant with declaration#!", N);
2146 Error_Msg_NE (Msg, N, N);
2147 end Conformance_Error;
2149 -- Start of processing for Check_Discriminant_Conformance
2152 while Present (Old_Discr) and then Present (New_Discr) loop
2154 New_Discr_Id := Defining_Identifier (New_Discr);
2156 -- The subtype mark of the discriminant on the full type
2157 -- has not been analyzed so we do it here. For an access
2158 -- discriminant a new type is created.
2160 if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then
2162 Access_Definition (N, Discriminant_Type (New_Discr));
2165 Analyze (Discriminant_Type (New_Discr));
2166 New_Discr_Type := Etype (Discriminant_Type (New_Discr));
2169 if not Conforming_Types
2170 (Etype (Old_Discr), New_Discr_Type, Fully_Conformant)
2172 Conformance_Error ("type of & does not match!", New_Discr_Id);
2178 if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then
2179 Conformance_Error ("name & does not match!", New_Discr_Id);
2183 -- Default expressions must match
2186 NewD : constant Boolean :=
2187 Present (Expression (New_Discr));
2188 OldD : constant Boolean :=
2189 Present (Expression (Parent (Old_Discr)));
2192 if NewD or OldD then
2194 -- The old default value has been analyzed and expanded,
2195 -- because the current full declaration will have frozen
2196 -- everything before. The new default values have not
2197 -- been expanded, so expand now to check conformance.
2200 Analyze_Default_Expression
2201 (Expression (New_Discr), New_Discr_Type);
2204 if not (NewD and OldD)
2205 or else not Fully_Conformant_Expressions
2206 (Expression (Parent (Old_Discr)),
2207 Expression (New_Discr))
2211 ("default expression for & does not match!",
2218 -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X)
2222 Old_Disc : constant Node_Id := Declaration_Node (Old_Discr);
2225 -- Grouping (use of comma in param lists) must be the same
2226 -- This is where we catch a misconformance like:
2229 -- A : Integer; B : Integer
2231 -- which are represented identically in the tree except
2232 -- for the setting of the flags More_Ids and Prev_Ids.
2234 if More_Ids (Old_Disc) /= More_Ids (New_Discr)
2235 or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr)
2238 ("grouping of & does not match!", New_Discr_Id);
2244 Next_Discriminant (Old_Discr);
2248 if Present (Old_Discr) then
2249 Conformance_Error ("too few discriminants!", Defining_Identifier (N));
2252 elsif Present (New_Discr) then
2254 ("too many discriminants!", Defining_Identifier (New_Discr));
2257 end Check_Discriminant_Conformance;
2259 ----------------------------
2260 -- Check_Fully_Conformant --
2261 ----------------------------
2263 procedure Check_Fully_Conformant
2264 (New_Id : Entity_Id;
2266 Err_Loc : Node_Id := Empty)
2272 (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc);
2273 end Check_Fully_Conformant;
2275 ---------------------------
2276 -- Check_Mode_Conformant --
2277 ---------------------------
2279 procedure Check_Mode_Conformant
2280 (New_Id : Entity_Id;
2282 Err_Loc : Node_Id := Empty;
2283 Get_Inst : Boolean := False)
2289 (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst);
2290 end Check_Mode_Conformant;
2296 procedure Check_Returns
2303 procedure Check_Statement_Sequence (L : List_Id);
2304 -- Internal recursive procedure to check a list of statements for proper
2305 -- termination by a return statement (or a transfer of control or a
2306 -- compound statement that is itself internally properly terminated).
2308 ------------------------------
2309 -- Check_Statement_Sequence --
2310 ------------------------------
2312 procedure Check_Statement_Sequence (L : List_Id) is
2316 Raise_Exception_Call : Boolean;
2317 -- Set True if statement sequence terminated by Raise_Exception call
2318 -- or a Reraise_Occurrence call.
2321 Raise_Exception_Call := False;
2323 -- Get last real statement
2325 Last_Stm := Last (L);
2327 -- Don't count pragmas
2329 while Nkind (Last_Stm) = N_Pragma
2331 -- Don't count call to SS_Release (can happen after Raise_Exception)
2334 (Nkind (Last_Stm) = N_Procedure_Call_Statement
2336 Nkind (Name (Last_Stm)) = N_Identifier
2338 Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release))
2340 -- Don't count exception junk
2343 ((Nkind (Last_Stm) = N_Goto_Statement
2344 or else Nkind (Last_Stm) = N_Label
2345 or else Nkind (Last_Stm) = N_Object_Declaration)
2346 and then Exception_Junk (Last_Stm))
2351 -- Here we have the "real" last statement
2353 Kind := Nkind (Last_Stm);
2355 -- Transfer of control, OK. Note that in the No_Return procedure
2356 -- case, we already diagnosed any explicit return statements, so
2357 -- we can treat them as OK in this context.
2359 if Is_Transfer (Last_Stm) then
2362 -- Check cases of explicit non-indirect procedure calls
2364 elsif Kind = N_Procedure_Call_Statement
2365 and then Is_Entity_Name (Name (Last_Stm))
2367 -- Check call to Raise_Exception procedure which is treated
2368 -- specially, as is a call to Reraise_Occurrence.
2370 -- We suppress the warning in these cases since it is likely that
2371 -- the programmer really does not expect to deal with the case
2372 -- of Null_Occurrence, and thus would find a warning about a
2373 -- missing return curious, and raising Program_Error does not
2374 -- seem such a bad behavior if this does occur.
2376 if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception)
2378 Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence)
2380 Raise_Exception_Call := True;
2382 -- For Raise_Exception call, test first argument, if it is
2383 -- an attribute reference for a 'Identity call, then we know
2384 -- that the call cannot possibly return.
2387 Arg : constant Node_Id :=
2388 Original_Node (First_Actual (Last_Stm));
2391 if Nkind (Arg) = N_Attribute_Reference
2392 and then Attribute_Name (Arg) = Name_Identity
2399 -- If statement, need to look inside if there is an else and check
2400 -- each constituent statement sequence for proper termination.
2402 elsif Kind = N_If_Statement
2403 and then Present (Else_Statements (Last_Stm))
2405 Check_Statement_Sequence (Then_Statements (Last_Stm));
2406 Check_Statement_Sequence (Else_Statements (Last_Stm));
2408 if Present (Elsif_Parts (Last_Stm)) then
2410 Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm));
2413 while Present (Elsif_Part) loop
2414 Check_Statement_Sequence (Then_Statements (Elsif_Part));
2422 -- Case statement, check each case for proper termination
2424 elsif Kind = N_Case_Statement then
2429 Case_Alt := First_Non_Pragma (Alternatives (Last_Stm));
2430 while Present (Case_Alt) loop
2431 Check_Statement_Sequence (Statements (Case_Alt));
2432 Next_Non_Pragma (Case_Alt);
2438 -- Block statement, check its handled sequence of statements
2440 elsif Kind = N_Block_Statement then
2446 (Handled_Statement_Sequence (Last_Stm), Mode, Err1);
2455 -- Loop statement. If there is an iteration scheme, we can definitely
2456 -- fall out of the loop. Similarly if there is an exit statement, we
2457 -- can fall out. In either case we need a following return.
2459 elsif Kind = N_Loop_Statement then
2460 if Present (Iteration_Scheme (Last_Stm))
2461 or else Has_Exit (Entity (Identifier (Last_Stm)))
2465 -- A loop with no exit statement or iteration scheme if either
2466 -- an inifite loop, or it has some other exit (raise/return).
2467 -- In either case, no warning is required.
2473 -- Timed entry call, check entry call and delay alternatives
2475 -- Note: in expanded code, the timed entry call has been converted
2476 -- to a set of expanded statements on which the check will work
2477 -- correctly in any case.
2479 elsif Kind = N_Timed_Entry_Call then
2481 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
2482 DCA : constant Node_Id := Delay_Alternative (Last_Stm);
2485 -- If statement sequence of entry call alternative is missing,
2486 -- then we can definitely fall through, and we post the error
2487 -- message on the entry call alternative itself.
2489 if No (Statements (ECA)) then
2492 -- If statement sequence of delay alternative is missing, then
2493 -- we can definitely fall through, and we post the error
2494 -- message on the delay alternative itself.
2496 -- Note: if both ECA and DCA are missing the return, then we
2497 -- post only one message, should be enough to fix the bugs.
2498 -- If not we will get a message next time on the DCA when the
2501 elsif No (Statements (DCA)) then
2504 -- Else check both statement sequences
2507 Check_Statement_Sequence (Statements (ECA));
2508 Check_Statement_Sequence (Statements (DCA));
2513 -- Conditional entry call, check entry call and else part
2515 -- Note: in expanded code, the conditional entry call has been
2516 -- converted to a set of expanded statements on which the check
2517 -- will work correctly in any case.
2519 elsif Kind = N_Conditional_Entry_Call then
2521 ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm);
2524 -- If statement sequence of entry call alternative is missing,
2525 -- then we can definitely fall through, and we post the error
2526 -- message on the entry call alternative itself.
2528 if No (Statements (ECA)) then
2531 -- Else check statement sequence and else part
2534 Check_Statement_Sequence (Statements (ECA));
2535 Check_Statement_Sequence (Else_Statements (Last_Stm));
2541 -- If we fall through, issue appropriate message
2545 if not Raise_Exception_Call then
2547 ("?RETURN statement missing following this statement!",
2550 ("\?Program_Error may be raised at run time",
2554 -- Note: we set Err even though we have not issued a warning
2555 -- because we still have a case of a missing return. This is
2556 -- an extremely marginal case, probably will never be noticed
2557 -- but we might as well get it right.
2563 ("implied return after this statement not allowed (No_Return)",
2566 end Check_Statement_Sequence;
2568 -- Start of processing for Check_Returns
2572 Check_Statement_Sequence (Statements (HSS));
2574 if Present (Exception_Handlers (HSS)) then
2575 Handler := First_Non_Pragma (Exception_Handlers (HSS));
2576 while Present (Handler) loop
2577 Check_Statement_Sequence (Statements (Handler));
2578 Next_Non_Pragma (Handler);
2583 ----------------------------
2584 -- Check_Subprogram_Order --
2585 ----------------------------
2587 procedure Check_Subprogram_Order (N : Node_Id) is
2589 function Subprogram_Name_Greater (S1, S2 : String) return Boolean;
2590 -- This is used to check if S1 > S2 in the sense required by this
2591 -- test, for example nameab < namec, but name2 < name10.
2593 function Subprogram_Name_Greater (S1, S2 : String) return Boolean is
2598 -- Remove trailing numeric parts
2601 while S1 (L1) in '0' .. '9' loop
2606 while S2 (L2) in '0' .. '9' loop
2610 -- If non-numeric parts non-equal, that's decisive
2612 if S1 (S1'First .. L1) < S2 (S2'First .. L2) then
2615 elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then
2618 -- If non-numeric parts equal, compare suffixed numeric parts. Note
2619 -- that a missing suffix is treated as numeric zero in this test.
2623 while L1 < S1'Last loop
2625 N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0');
2629 while L2 < S2'Last loop
2631 N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0');
2636 end Subprogram_Name_Greater;
2638 -- Start of processing for Check_Subprogram_Order
2641 -- Check body in alpha order if this is option
2643 if Style_Check_Subprogram_Order
2644 and then Nkind (N) = N_Subprogram_Body
2645 and then Comes_From_Source (N)
2646 and then In_Extended_Main_Source_Unit (N)
2650 renames Scope_Stack.Table
2651 (Scope_Stack.Last).Last_Subprogram_Name;
2653 Body_Id : constant Entity_Id :=
2654 Defining_Entity (Specification (N));
2657 Get_Decoded_Name_String (Chars (Body_Id));
2660 if Subprogram_Name_Greater
2661 (LSN.all, Name_Buffer (1 .. Name_Len))
2663 Style.Subprogram_Not_In_Alpha_Order (Body_Id);
2669 LSN := new String'(Name_Buffer (1 .. Name_Len));
2672 end Check_Subprogram_Order;
2674 ------------------------------
2675 -- Check_Subtype_Conformant --
2676 ------------------------------
2678 procedure Check_Subtype_Conformant
2679 (New_Id : Entity_Id;
2681 Err_Loc : Node_Id := Empty)
2687 (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc);
2688 end Check_Subtype_Conformant;
2690 ---------------------------
2691 -- Check_Type_Conformant --
2692 ---------------------------
2694 procedure Check_Type_Conformant
2695 (New_Id : Entity_Id;
2697 Err_Loc : Node_Id := Empty)
2703 (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc);
2704 end Check_Type_Conformant;
2706 ----------------------
2707 -- Conforming_Types --
2708 ----------------------
2710 function Conforming_Types
2713 Ctype : Conformance_Type;
2714 Get_Inst : Boolean := False)
2717 Type_1 : Entity_Id := T1;
2718 Type_2 : Entity_Id := T2;
2720 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean;
2721 -- If neither T1 nor T2 are generic actual types, or if they are
2722 -- in different scopes (e.g. parent and child instances), then verify
2723 -- that the base types are equal. Otherwise T1 and T2 must be
2724 -- on the same subtype chain. The whole purpose of this procedure
2725 -- is to prevent spurious ambiguities in an instantiation that may
2726 -- arise if two distinct generic types are instantiated with the
2729 ----------------------
2730 -- Base_Types_Match --
2731 ----------------------
2733 function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is
2738 elsif Base_Type (T1) = Base_Type (T2) then
2740 -- The following is too permissive. A more precise test must
2741 -- check that the generic actual is an ancestor subtype of the
2744 return not Is_Generic_Actual_Type (T1)
2745 or else not Is_Generic_Actual_Type (T2)
2746 or else Scope (T1) /= Scope (T2);
2751 end Base_Types_Match;
2754 -- The context is an instance association for a formal
2755 -- access-to-subprogram type; the formal parameter types
2756 -- require mapping because they may denote other formal
2757 -- parameters of the generic unit.
2760 Type_1 := Get_Instance_Of (T1);
2761 Type_2 := Get_Instance_Of (T2);
2764 -- First see if base types match
2766 if Base_Types_Match (Type_1, Type_2) then
2767 return Ctype <= Mode_Conformant
2768 or else Subtypes_Statically_Match (Type_1, Type_2);
2770 elsif Is_Incomplete_Or_Private_Type (Type_1)
2771 and then Present (Full_View (Type_1))
2772 and then Base_Types_Match (Full_View (Type_1), Type_2)
2774 return Ctype <= Mode_Conformant
2775 or else Subtypes_Statically_Match (Full_View (Type_1), Type_2);
2777 elsif Ekind (Type_2) = E_Incomplete_Type
2778 and then Present (Full_View (Type_2))
2779 and then Base_Types_Match (Type_1, Full_View (Type_2))
2781 return Ctype <= Mode_Conformant
2782 or else Subtypes_Statically_Match (Type_1, Full_View (Type_2));
2785 -- Test anonymous access type case. For this case, static subtype
2786 -- matching is required for mode conformance (RM 6.3.1(15))
2788 if Ekind (Type_1) = E_Anonymous_Access_Type
2789 and then Ekind (Type_2) = E_Anonymous_Access_Type
2792 Desig_1 : Entity_Id;
2793 Desig_2 : Entity_Id;
2796 Desig_1 := Directly_Designated_Type (Type_1);
2798 -- An access parameter can designate an incomplete type.
2800 if Ekind (Desig_1) = E_Incomplete_Type
2801 and then Present (Full_View (Desig_1))
2803 Desig_1 := Full_View (Desig_1);
2806 Desig_2 := Directly_Designated_Type (Type_2);
2808 if Ekind (Desig_2) = E_Incomplete_Type
2809 and then Present (Full_View (Desig_2))
2811 Desig_2 := Full_View (Desig_2);
2814 -- The context is an instance association for a formal
2815 -- access-to-subprogram type; formal access parameter
2816 -- designated types require mapping because they may
2817 -- denote other formal parameters of the generic unit.
2820 Desig_1 := Get_Instance_Of (Desig_1);
2821 Desig_2 := Get_Instance_Of (Desig_2);
2824 -- It is possible for a Class_Wide_Type to be introduced for
2825 -- an incomplete type, in which case there is a separate class_
2826 -- wide type for the full view. The types conform if their
2827 -- Etypes conform, i.e. one may be the full view of the other.
2828 -- This can only happen in the context of an access parameter,
2829 -- other uses of an incomplete Class_Wide_Type are illegal.
2831 if Ekind (Desig_1) = E_Class_Wide_Type
2832 and then Ekind (Desig_2) = E_Class_Wide_Type
2835 Conforming_Types (Etype (Desig_1), Etype (Desig_2), Ctype);
2837 return Base_Type (Desig_1) = Base_Type (Desig_2)
2838 and then (Ctype = Type_Conformant
2840 Subtypes_Statically_Match (Desig_1, Desig_2));
2844 -- Otherwise definitely no match
2850 end Conforming_Types;
2852 --------------------------
2853 -- Create_Extra_Formals --
2854 --------------------------
2856 procedure Create_Extra_Formals (E : Entity_Id) is
2858 Last_Formal : Entity_Id;
2859 Last_Extra : Entity_Id;
2860 Formal_Type : Entity_Id;
2861 P_Formal : Entity_Id := Empty;
2863 function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id;
2864 -- Add an extra formal, associated with the current Formal. The
2865 -- extra formal is added to the list of extra formals, and also
2866 -- returned as the result. These formals are always of mode IN.
2868 function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id is
2869 EF : constant Entity_Id :=
2870 Make_Defining_Identifier (Sloc (Formal),
2871 Chars => New_External_Name (Chars (Formal), 'F'));
2874 -- We never generate extra formals if expansion is not active
2875 -- because we don't need them unless we are generating code.
2877 if not Expander_Active then
2881 -- A little optimization. Never generate an extra formal for
2882 -- the _init operand of an initialization procedure, since it
2883 -- could never be used.
2885 if Chars (Formal) = Name_uInit then
2889 Set_Ekind (EF, E_In_Parameter);
2890 Set_Actual_Subtype (EF, Typ);
2891 Set_Etype (EF, Typ);
2892 Set_Scope (EF, Scope (Formal));
2893 Set_Mechanism (EF, Default_Mechanism);
2894 Set_Formal_Validity (EF);
2896 Set_Extra_Formal (Last_Extra, EF);
2899 end Add_Extra_Formal;
2901 -- Start of processing for Create_Extra_Formals
2904 -- If this is a derived subprogram then the subtypes of the
2905 -- parent subprogram's formal parameters will be used to
2906 -- to determine the need for extra formals.
2908 if Is_Overloadable (E) and then Present (Alias (E)) then
2909 P_Formal := First_Formal (Alias (E));
2912 Last_Extra := Empty;
2913 Formal := First_Formal (E);
2914 while Present (Formal) loop
2915 Last_Extra := Formal;
2916 Next_Formal (Formal);
2919 -- If Extra_formals where already created, don't do it again
2920 -- This situation may arise for subprogram types created as part
2921 -- of dispatching calls (see Expand_Dispatch_Call)
2923 if Present (Last_Extra) and then
2924 Present (Extra_Formal (Last_Extra))
2929 Formal := First_Formal (E);
2931 while Present (Formal) loop
2933 -- Create extra formal for supporting the attribute 'Constrained.
2934 -- The case of a private type view without discriminants also
2935 -- requires the extra formal if the underlying type has defaulted
2938 if Ekind (Formal) /= E_In_Parameter then
2939 if Present (P_Formal) then
2940 Formal_Type := Etype (P_Formal);
2942 Formal_Type := Etype (Formal);
2945 if not Has_Discriminants (Formal_Type)
2946 and then Ekind (Formal_Type) in Private_Kind
2947 and then Present (Underlying_Type (Formal_Type))
2949 Formal_Type := Underlying_Type (Formal_Type);
2952 if Has_Discriminants (Formal_Type)
2954 ((not Is_Constrained (Formal_Type)
2955 and then not Is_Indefinite_Subtype (Formal_Type))
2956 or else Present (Extra_Formal (Formal)))
2958 Set_Extra_Constrained
2959 (Formal, Add_Extra_Formal (Standard_Boolean));
2963 -- Create extra formal for supporting accessibility checking
2965 -- This is suppressed if we specifically suppress accessibility
2966 -- checks for either the subprogram, or the package in which it
2967 -- resides. However, we do not suppress it simply if the scope
2968 -- has accessibility checks suppressed, since this could cause
2969 -- trouble when clients are compiled with a different suppression
2970 -- setting. The explicit checks are safe from this point of view.
2972 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type
2974 (Suppress_Accessibility_Checks (E)
2976 Suppress_Accessibility_Checks (Scope (E)))
2978 (not Present (P_Formal)
2979 or else Present (Extra_Accessibility (P_Formal)))
2981 -- Temporary kludge: for now we avoid creating the extra
2982 -- formal for access parameters of protected operations
2983 -- because of problem with the case of internal protected
2986 if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition
2987 and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body
2989 Set_Extra_Accessibility
2990 (Formal, Add_Extra_Formal (Standard_Natural));
2994 if Present (P_Formal) then
2995 Next_Formal (P_Formal);
2998 Last_Formal := Formal;
2999 Next_Formal (Formal);
3001 end Create_Extra_Formals;
3003 -----------------------------
3004 -- Enter_Overloaded_Entity --
3005 -----------------------------
3007 procedure Enter_Overloaded_Entity (S : Entity_Id) is
3008 E : Entity_Id := Current_Entity_In_Scope (S);
3009 C_E : Entity_Id := Current_Entity (S);
3013 Set_Has_Homonym (E);
3014 Set_Has_Homonym (S);
3017 Set_Is_Immediately_Visible (S);
3018 Set_Scope (S, Current_Scope);
3020 -- Chain new entity if front of homonym in current scope, so that
3021 -- homonyms are contiguous.
3026 while Homonym (C_E) /= E loop
3027 C_E := Homonym (C_E);
3030 Set_Homonym (C_E, S);
3034 Set_Current_Entity (S);
3039 Append_Entity (S, Current_Scope);
3040 Set_Public_Status (S);
3042 if Debug_Flag_E then
3043 Write_Str ("New overloaded entity chain: ");
3044 Write_Name (Chars (S));
3047 while Present (E) loop
3048 Write_Str (" "); Write_Int (Int (E));
3055 -- Generate warning for hiding
3058 and then Comes_From_Source (S)
3059 and then In_Extended_Main_Source_Unit (S)
3066 -- Warn unless genuine overloading
3068 if (not Is_Overloadable (E))
3069 or else Subtype_Conformant (E, S)
3071 Error_Msg_Sloc := Sloc (E);
3072 Error_Msg_N ("declaration of & hides one#?", S);
3076 end Enter_Overloaded_Entity;
3078 -----------------------------
3079 -- Find_Corresponding_Spec --
3080 -----------------------------
3082 function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is
3083 Spec : constant Node_Id := Specification (N);
3084 Designator : constant Entity_Id := Defining_Entity (Spec);
3089 E := Current_Entity (Designator);
3091 while Present (E) loop
3093 -- We are looking for a matching spec. It must have the same scope,
3094 -- and the same name, and either be type conformant, or be the case
3095 -- of a library procedure spec and its body (which belong to one
3096 -- another regardless of whether they are type conformant or not).
3098 if Scope (E) = Current_Scope then
3099 if (Current_Scope = Standard_Standard
3100 or else (Ekind (E) = Ekind (Designator)
3102 Type_Conformant (E, Designator)))
3104 -- Within an instantiation, we know that spec and body are
3105 -- subtype conformant, because they were subtype conformant
3106 -- in the generic. We choose the subtype-conformant entity
3107 -- here as well, to resolve spurious ambiguities in the
3108 -- instance that were not present in the generic (i.e. when
3109 -- two different types are given the same actual). If we are
3110 -- looking for a spec to match a body, full conformance is
3114 Set_Convention (Designator, Convention (E));
3116 if Nkind (N) = N_Subprogram_Body
3117 and then Present (Homonym (E))
3118 and then not Fully_Conformant (E, Designator)
3122 elsif not Subtype_Conformant (E, Designator) then
3127 if not Has_Completion (E) then
3129 if Nkind (N) /= N_Subprogram_Body_Stub then
3130 Set_Corresponding_Spec (N, E);
3133 Set_Has_Completion (E);
3136 elsif Nkind (Parent (N)) = N_Subunit then
3138 -- If this is the proper body of a subunit, the completion
3139 -- flag is set when analyzing the stub.
3143 -- If body already exists, this is an error unless the
3144 -- previous declaration is the implicit declaration of
3145 -- a derived subprogram, or this is a spurious overloading
3148 elsif No (Alias (E))
3149 and then not Is_Intrinsic_Subprogram (E)
3150 and then not In_Instance
3152 Error_Msg_Sloc := Sloc (E);
3153 if Is_Imported (E) then
3155 ("body not allowed for imported subprogram & declared#",
3158 Error_Msg_NE ("duplicate body for & declared#", N, E);
3162 elsif Is_Child_Unit (E)
3164 Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body
3166 Nkind (Parent (Unit_Declaration_Node (Designator)))
3167 = N_Compilation_Unit
3170 -- Child units cannot be overloaded, so a conformance mismatch
3171 -- between body and a previous spec is an error.
3174 ("body of child unit does not match previous declaration", N);
3182 -- On exit, we know that no previous declaration of subprogram exists
3185 end Find_Corresponding_Spec;
3187 ----------------------
3188 -- Fully_Conformant --
3189 ----------------------
3191 function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
3195 Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result);
3197 end Fully_Conformant;
3199 ----------------------------------
3200 -- Fully_Conformant_Expressions --
3201 ----------------------------------
3203 function Fully_Conformant_Expressions
3204 (Given_E1 : Node_Id;
3208 E1 : constant Node_Id := Original_Node (Given_E1);
3209 E2 : constant Node_Id := Original_Node (Given_E2);
3210 -- We always test conformance on original nodes, since it is possible
3211 -- for analysis and/or expansion to make things look as though they
3212 -- conform when they do not, e.g. by converting 1+2 into 3.
3214 function FCE (Given_E1, Given_E2 : Node_Id) return Boolean
3215 renames Fully_Conformant_Expressions;
3217 function FCL (L1, L2 : List_Id) return Boolean;
3218 -- Compare elements of two lists for conformance. Elements have to
3219 -- be conformant, and actuals inserted as default parameters do not
3220 -- match explicit actuals with the same value.
3222 function FCO (Op_Node, Call_Node : Node_Id) return Boolean;
3223 -- Compare an operator node with a function call.
3229 function FCL (L1, L2 : List_Id) return Boolean is
3233 if L1 = No_List then
3239 if L2 = No_List then
3245 -- Compare two lists, skipping rewrite insertions (we want to
3246 -- compare the original trees, not the expanded versions!)
3249 if Is_Rewrite_Insertion (N1) then
3251 elsif Is_Rewrite_Insertion (N2) then
3257 elsif not FCE (N1, N2) then
3270 function FCO (Op_Node, Call_Node : Node_Id) return Boolean is
3271 Actuals : constant List_Id := Parameter_Associations (Call_Node);
3276 or else Entity (Op_Node) /= Entity (Name (Call_Node))
3281 Act := First (Actuals);
3283 if Nkind (Op_Node) in N_Binary_Op then
3285 if not FCE (Left_Opnd (Op_Node), Act) then
3292 return Present (Act)
3293 and then FCE (Right_Opnd (Op_Node), Act)
3294 and then No (Next (Act));
3298 -- Start of processing for Fully_Conformant_Expressions
3301 -- Non-conformant if paren count does not match. Note: if some idiot
3302 -- complains that we don't do this right for more than 3 levels of
3303 -- parentheses, they will be treated with the respect they deserve :-)
3305 if Paren_Count (E1) /= Paren_Count (E2) then
3308 -- If same entities are referenced, then they are conformant
3309 -- even if they have different forms (RM 8.3.1(19-20)).
3311 elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then
3312 if Present (Entity (E1)) then
3313 return Entity (E1) = Entity (E2)
3314 or else (Chars (Entity (E1)) = Chars (Entity (E2))
3315 and then Ekind (Entity (E1)) = E_Discriminant
3316 and then Ekind (Entity (E2)) = E_In_Parameter);
3318 elsif Nkind (E1) = N_Expanded_Name
3319 and then Nkind (E2) = N_Expanded_Name
3320 and then Nkind (Selector_Name (E1)) = N_Character_Literal
3321 and then Nkind (Selector_Name (E2)) = N_Character_Literal
3323 return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2));
3326 -- Identifiers in component associations don't always have
3327 -- entities, but their names must conform.
3329 return Nkind (E1) = N_Identifier
3330 and then Nkind (E2) = N_Identifier
3331 and then Chars (E1) = Chars (E2);
3334 elsif Nkind (E1) = N_Character_Literal
3335 and then Nkind (E2) = N_Expanded_Name
3337 return Nkind (Selector_Name (E2)) = N_Character_Literal
3338 and then Chars (E1) = Chars (Selector_Name (E2));
3340 elsif Nkind (E2) = N_Character_Literal
3341 and then Nkind (E1) = N_Expanded_Name
3343 return Nkind (Selector_Name (E1)) = N_Character_Literal
3344 and then Chars (E2) = Chars (Selector_Name (E1));
3346 elsif Nkind (E1) in N_Op
3347 and then Nkind (E2) = N_Function_Call
3349 return FCO (E1, E2);
3351 elsif Nkind (E2) in N_Op
3352 and then Nkind (E1) = N_Function_Call
3354 return FCO (E2, E1);
3356 -- Otherwise we must have the same syntactic entity
3358 elsif Nkind (E1) /= Nkind (E2) then
3361 -- At this point, we specialize by node type
3368 FCL (Expressions (E1), Expressions (E2))
3369 and then FCL (Component_Associations (E1),
3370 Component_Associations (E2));
3373 if Nkind (Expression (E1)) = N_Qualified_Expression
3375 Nkind (Expression (E2)) = N_Qualified_Expression
3377 return FCE (Expression (E1), Expression (E2));
3379 -- Check that the subtype marks and any constraints
3384 Indic1 : constant Node_Id := Expression (E1);
3385 Indic2 : constant Node_Id := Expression (E2);
3390 if Nkind (Indic1) /= N_Subtype_Indication then
3392 Nkind (Indic2) /= N_Subtype_Indication
3393 and then Entity (Indic1) = Entity (Indic2);
3395 elsif Nkind (Indic2) /= N_Subtype_Indication then
3397 Nkind (Indic1) /= N_Subtype_Indication
3398 and then Entity (Indic1) = Entity (Indic2);
3401 if Entity (Subtype_Mark (Indic1)) /=
3402 Entity (Subtype_Mark (Indic2))
3407 Elt1 := First (Constraints (Constraint (Indic1)));
3408 Elt2 := First (Constraints (Constraint (Indic2)));
3410 while Present (Elt1) and then Present (Elt2) loop
3411 if not FCE (Elt1, Elt2) then
3424 when N_Attribute_Reference =>
3426 Attribute_Name (E1) = Attribute_Name (E2)
3427 and then FCL (Expressions (E1), Expressions (E2));
3431 Entity (E1) = Entity (E2)
3432 and then FCE (Left_Opnd (E1), Left_Opnd (E2))
3433 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
3435 when N_And_Then | N_Or_Else | N_In | N_Not_In =>
3437 FCE (Left_Opnd (E1), Left_Opnd (E2))
3439 FCE (Right_Opnd (E1), Right_Opnd (E2));
3441 when N_Character_Literal =>
3443 Char_Literal_Value (E1) = Char_Literal_Value (E2);
3445 when N_Component_Association =>
3447 FCL (Choices (E1), Choices (E2))
3448 and then FCE (Expression (E1), Expression (E2));
3450 when N_Conditional_Expression =>
3452 FCL (Expressions (E1), Expressions (E2));
3454 when N_Explicit_Dereference =>
3456 FCE (Prefix (E1), Prefix (E2));
3458 when N_Extension_Aggregate =>
3460 FCL (Expressions (E1), Expressions (E2))
3461 and then Null_Record_Present (E1) =
3462 Null_Record_Present (E2)
3463 and then FCL (Component_Associations (E1),
3464 Component_Associations (E2));
3466 when N_Function_Call =>
3468 FCE (Name (E1), Name (E2))
3469 and then FCL (Parameter_Associations (E1),
3470 Parameter_Associations (E2));
3472 when N_Indexed_Component =>
3474 FCE (Prefix (E1), Prefix (E2))
3475 and then FCL (Expressions (E1), Expressions (E2));
3477 when N_Integer_Literal =>
3478 return (Intval (E1) = Intval (E2));
3483 when N_Operator_Symbol =>
3485 Chars (E1) = Chars (E2);
3487 when N_Others_Choice =>
3490 when N_Parameter_Association =>
3493 Chars (Selector_Name (E1)) = Chars (Selector_Name (E2))
3494 and then FCE (Explicit_Actual_Parameter (E1),
3495 Explicit_Actual_Parameter (E2));
3497 when N_Qualified_Expression =>
3499 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3500 and then FCE (Expression (E1), Expression (E2));
3504 FCE (Low_Bound (E1), Low_Bound (E2))
3505 and then FCE (High_Bound (E1), High_Bound (E2));
3507 when N_Real_Literal =>
3508 return (Realval (E1) = Realval (E2));
3510 when N_Selected_Component =>
3512 FCE (Prefix (E1), Prefix (E2))
3513 and then FCE (Selector_Name (E1), Selector_Name (E2));
3517 FCE (Prefix (E1), Prefix (E2))
3518 and then FCE (Discrete_Range (E1), Discrete_Range (E2));
3520 when N_String_Literal =>
3522 S1 : constant String_Id := Strval (E1);
3523 S2 : constant String_Id := Strval (E2);
3524 L1 : constant Nat := String_Length (S1);
3525 L2 : constant Nat := String_Length (S2);
3532 for J in 1 .. L1 loop
3533 if Get_String_Char (S1, J) /=
3534 Get_String_Char (S2, J)
3544 when N_Type_Conversion =>
3546 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3547 and then FCE (Expression (E1), Expression (E2));
3551 Entity (E1) = Entity (E2)
3552 and then FCE (Right_Opnd (E1), Right_Opnd (E2));
3554 when N_Unchecked_Type_Conversion =>
3556 FCE (Subtype_Mark (E1), Subtype_Mark (E2))
3557 and then FCE (Expression (E1), Expression (E2));
3559 -- All other node types cannot appear in this context. Strictly
3560 -- we should raise a fatal internal error. Instead we just ignore
3561 -- the nodes. This means that if anyone makes a mistake in the
3562 -- expander and mucks an expression tree irretrievably, the
3563 -- result will be a failure to detect a (probably very obscure)
3564 -- case of non-conformance, which is better than bombing on some
3565 -- case where two expressions do in fact conform.
3572 end Fully_Conformant_Expressions;
3574 --------------------
3575 -- Install_Entity --
3576 --------------------
3578 procedure Install_Entity (E : Entity_Id) is
3579 Prev : constant Entity_Id := Current_Entity (E);
3582 Set_Is_Immediately_Visible (E);
3583 Set_Current_Entity (E);
3584 Set_Homonym (E, Prev);
3587 ---------------------
3588 -- Install_Formals --
3589 ---------------------
3591 procedure Install_Formals (Id : Entity_Id) is
3595 F := First_Formal (Id);
3597 while Present (F) loop
3601 end Install_Formals;
3603 ---------------------------------
3604 -- Is_Non_Overriding_Operation --
3605 ---------------------------------
3607 function Is_Non_Overriding_Operation
3608 (Prev_E : Entity_Id;
3614 G_Typ : Entity_Id := Empty;
3616 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id;
3617 -- If F_Type is a derived type associated with a generic actual
3618 -- subtype, then return its Generic_Parent_Type attribute, else
3621 function Types_Correspond
3622 (P_Type : Entity_Id;
3625 -- Returns true if and only if the types (or designated types
3626 -- in the case of anonymous access types) are the same or N_Type
3627 -- is derived directly or indirectly from P_Type.
3629 -----------------------------
3630 -- Get_Generic_Parent_Type --
3631 -----------------------------
3633 function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is
3638 if Is_Derived_Type (F_Typ)
3639 and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration
3641 -- The tree must be traversed to determine the parent
3642 -- subtype in the generic unit, which unfortunately isn't
3643 -- always available via semantic attributes. ???
3644 -- (Note: The use of Original_Node is needed for cases
3645 -- where a full derived type has been rewritten.)
3647 Indic := Subtype_Indication
3648 (Type_Definition (Original_Node (Parent (F_Typ))));
3650 if Nkind (Indic) = N_Subtype_Indication then
3651 G_Typ := Entity (Subtype_Mark (Indic));
3653 G_Typ := Entity (Indic);
3656 if Nkind (Parent (G_Typ)) = N_Subtype_Declaration
3657 and then Present (Generic_Parent_Type (Parent (G_Typ)))
3659 return Generic_Parent_Type (Parent (G_Typ));
3664 end Get_Generic_Parent_Type;
3666 ----------------------
3667 -- Types_Correspond --
3668 ----------------------
3670 function Types_Correspond
3671 (P_Type : Entity_Id;
3675 Prev_Type : Entity_Id := Base_Type (P_Type);
3676 New_Type : Entity_Id := Base_Type (N_Type);
3679 if Ekind (Prev_Type) = E_Anonymous_Access_Type then
3680 Prev_Type := Designated_Type (Prev_Type);
3683 if Ekind (New_Type) = E_Anonymous_Access_Type then
3684 New_Type := Designated_Type (New_Type);
3687 if Prev_Type = New_Type then
3690 elsif not Is_Class_Wide_Type (New_Type) then
3691 while Etype (New_Type) /= New_Type loop
3692 New_Type := Etype (New_Type);
3693 if New_Type = Prev_Type then
3699 end Types_Correspond;
3701 -- Start of processing for Is_Non_Overriding_Operation
3704 -- In the case where both operations are implicit derived
3705 -- subprograms then neither overrides the other. This can
3706 -- only occur in certain obscure cases (e.g., derivation
3707 -- from homographs created in a generic instantiation).
3709 if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then
3712 elsif Ekind (Current_Scope) = E_Package
3713 and then Is_Generic_Instance (Current_Scope)
3714 and then In_Private_Part (Current_Scope)
3715 and then Comes_From_Source (New_E)
3717 -- We examine the formals and result subtype of the inherited
3718 -- operation, to determine whether their type is derived from
3719 -- (the instance of) a generic type.
3721 Formal := First_Formal (Prev_E);
3723 while Present (Formal) loop
3724 F_Typ := Base_Type (Etype (Formal));
3726 if Ekind (F_Typ) = E_Anonymous_Access_Type then
3727 F_Typ := Designated_Type (F_Typ);
3730 G_Typ := Get_Generic_Parent_Type (F_Typ);
3732 Next_Formal (Formal);
3735 if not Present (G_Typ) and then Ekind (Prev_E) = E_Function then
3736 G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E)));
3743 -- If the generic type is a private type, then the original
3744 -- operation was not overriding in the generic, because there was
3745 -- no primitive operation to override.
3747 if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration
3748 and then Nkind (Formal_Type_Definition (Parent (G_Typ))) =
3749 N_Formal_Private_Type_Definition
3753 -- The generic parent type is the ancestor of a formal derived
3754 -- type declaration. We need to check whether it has a primitive
3755 -- operation that should be overridden by New_E in the generic.
3759 P_Formal : Entity_Id;
3760 N_Formal : Entity_Id;
3764 Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ));
3767 while Present (Prim_Elt) loop
3768 P_Prim := Node (Prim_Elt);
3769 if Chars (P_Prim) = Chars (New_E)
3770 and then Ekind (P_Prim) = Ekind (New_E)
3772 P_Formal := First_Formal (P_Prim);
3773 N_Formal := First_Formal (New_E);
3774 while Present (P_Formal) and then Present (N_Formal) loop
3775 P_Typ := Etype (P_Formal);
3776 N_Typ := Etype (N_Formal);
3778 if not Types_Correspond (P_Typ, N_Typ) then
3782 Next_Entity (P_Formal);
3783 Next_Entity (N_Formal);
3786 -- Found a matching primitive operation belonging to
3787 -- the formal ancestor type, so the new subprogram
3790 if not Present (P_Formal)
3791 and then not Present (N_Formal)
3792 and then (Ekind (New_E) /= E_Function
3795 (Etype (P_Prim), Etype (New_E)))
3801 Next_Elmt (Prim_Elt);
3804 -- If no match found, then the new subprogram does
3805 -- not override in the generic (nor in the instance).
3813 end Is_Non_Overriding_Operation;
3815 ------------------------------
3816 -- Make_Inequality_Operator --
3817 ------------------------------
3819 -- S is the defining identifier of an equality operator. We build a
3820 -- subprogram declaration with the right signature. This operation is
3821 -- intrinsic, because it is always expanded as the negation of the
3822 -- call to the equality function.
3824 procedure Make_Inequality_Operator (S : Entity_Id) is
3825 Loc : constant Source_Ptr := Sloc (S);
3828 Op_Name : Entity_Id;
3834 -- Check that equality was properly defined.
3836 if No (Next_Formal (First_Formal (S))) then
3840 A := Make_Defining_Identifier (Loc, Chars (First_Formal (S)));
3841 B := Make_Defining_Identifier (Loc,
3842 Chars (Next_Formal (First_Formal (S))));
3844 Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne);
3846 Formals := New_List (
3847 Make_Parameter_Specification (Loc,
3848 Defining_Identifier => A,
3850 New_Reference_To (Etype (First_Formal (S)), Loc)),
3852 Make_Parameter_Specification (Loc,
3853 Defining_Identifier => B,
3855 New_Reference_To (Etype (Next_Formal (First_Formal (S))), Loc)));
3858 Make_Subprogram_Declaration (Loc,
3860 Make_Function_Specification (Loc,
3861 Defining_Unit_Name => Op_Name,
3862 Parameter_Specifications => Formals,
3863 Subtype_Mark => New_Reference_To (Standard_Boolean, Loc)));
3865 -- Insert inequality right after equality if it is explicit or after
3866 -- the derived type when implicit. These entities are created only
3867 -- for visibility purposes, and eventually replaced in the course of
3868 -- expansion, so they do not need to be attached to the tree and seen
3869 -- by the back-end. Keeping them internal also avoids spurious freezing
3870 -- problems. The parent field is set simply to make analysis safe.
3872 if No (Alias (S)) then
3873 Set_Parent (Decl, Parent (Unit_Declaration_Node (S)));
3875 Set_Parent (Decl, Parent (Parent (Etype (First_Formal (S)))));
3878 Mark_Rewrite_Insertion (Decl);
3879 Set_Is_Intrinsic_Subprogram (Op_Name);
3881 Set_Has_Completion (Op_Name);
3882 Set_Corresponding_Equality (Op_Name, S);
3883 Set_Is_Abstract (Op_Name, Is_Abstract (S));
3885 end Make_Inequality_Operator;
3887 ----------------------
3888 -- May_Need_Actuals --
3889 ----------------------
3891 procedure May_Need_Actuals (Fun : Entity_Id) is
3896 F := First_Formal (Fun);
3899 while Present (F) loop
3900 if No (Default_Value (F)) then
3908 Set_Needs_No_Actuals (Fun, B);
3909 end May_Need_Actuals;
3911 ---------------------
3912 -- Mode_Conformant --
3913 ---------------------
3915 function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
3919 Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result);
3921 end Mode_Conformant;
3923 ---------------------------
3924 -- New_Overloaded_Entity --
3925 ---------------------------
3927 procedure New_Overloaded_Entity
3929 Derived_Type : Entity_Id := Empty)
3931 E : Entity_Id := Current_Entity_In_Scope (S);
3932 Prev_Vis : Entity_Id := Empty;
3934 function Is_Private_Declaration (E : Entity_Id) return Boolean;
3935 -- Check that E is declared in the private part of the current package,
3936 -- or in the package body, where it may hide a previous declaration.
3937 -- We can' use In_Private_Part by itself because this flag is also
3938 -- set when freezing entities, so we must examine the place of the
3939 -- declaration in the tree, and recognize wrapper packages as well.
3941 procedure Maybe_Primitive_Operation (Overriding : Boolean := False);
3942 -- If the subprogram being analyzed is a primitive operation of
3943 -- the type of one of its formals, set the corresponding flag.
3945 ----------------------------
3946 -- Is_Private_Declaration --
3947 ----------------------------
3949 function Is_Private_Declaration (E : Entity_Id) return Boolean is
3950 Priv_Decls : List_Id;
3951 Decl : constant Node_Id := Unit_Declaration_Node (E);
3954 if Is_Package (Current_Scope)
3955 and then In_Private_Part (Current_Scope)
3958 Private_Declarations (
3959 Specification (Unit_Declaration_Node (Current_Scope)));
3961 return In_Package_Body (Current_Scope)
3962 or else List_Containing (Decl) = Priv_Decls
3963 or else (Nkind (Parent (Decl)) = N_Package_Specification
3964 and then not Is_Compilation_Unit (
3965 Defining_Entity (Parent (Decl)))
3966 and then List_Containing (Parent (Parent (Decl)))
3971 end Is_Private_Declaration;
3973 -------------------------------
3974 -- Maybe_Primitive_Operation --
3975 -------------------------------
3977 procedure Maybe_Primitive_Operation (Overriding : Boolean := False) is
3982 function Visible_Part_Type (T : Entity_Id) return Boolean;
3983 -- Returns true if T is declared in the visible part of
3984 -- the current package scope; otherwise returns false.
3985 -- Assumes that T is declared in a package.
3987 procedure Check_Private_Overriding (T : Entity_Id);
3988 -- Checks that if a primitive abstract subprogram of a visible
3989 -- abstract type is declared in a private part, then it must
3990 -- override an abstract subprogram declared in the visible part.
3991 -- Also checks that if a primitive function with a controlling
3992 -- result is declared in a private part, then it must override
3993 -- a function declared in the visible part.
3995 ------------------------------
3996 -- Check_Private_Overriding --
3997 ------------------------------
3999 procedure Check_Private_Overriding (T : Entity_Id) is
4001 if Ekind (Current_Scope) = E_Package
4002 and then In_Private_Part (Current_Scope)
4003 and then Visible_Part_Type (T)
4004 and then not In_Instance
4007 and then Is_Abstract (S)
4008 and then (not Overriding or else not Is_Abstract (E))
4010 Error_Msg_N ("abstract subprograms must be visible "
4011 & "('R'M 3.9.3(10))!", S);
4013 elsif Ekind (S) = E_Function
4014 and then Is_Tagged_Type (T)
4015 and then T = Base_Type (Etype (S))
4016 and then not Overriding
4019 ("private function with tagged result must"
4020 & " override visible-part function", S);
4022 ("\move subprogram to the visible part"
4023 & " ('R'M 3.9.3(10))", S);
4026 end Check_Private_Overriding;
4028 -----------------------
4029 -- Visible_Part_Type --
4030 -----------------------
4032 function Visible_Part_Type (T : Entity_Id) return Boolean is
4033 P : constant Node_Id := Unit_Declaration_Node (Scope (T));
4037 -- If the entity is a private type, then it must be
4038 -- declared in a visible part.
4040 if Ekind (T) in Private_Kind then
4044 -- Otherwise, we traverse the visible part looking for its
4045 -- corresponding declaration. We cannot use the declaration
4046 -- node directly because in the private part the entity of a
4047 -- private type is the one in the full view, which does not
4048 -- indicate that it is the completion of something visible.
4050 N := First (Visible_Declarations (Specification (P)));
4051 while Present (N) loop
4052 if Nkind (N) = N_Full_Type_Declaration
4053 and then Present (Defining_Identifier (N))
4054 and then T = Defining_Identifier (N)
4058 elsif (Nkind (N) = N_Private_Type_Declaration
4060 Nkind (N) = N_Private_Extension_Declaration)
4061 and then Present (Defining_Identifier (N))
4062 and then T = Full_View (Defining_Identifier (N))
4071 end Visible_Part_Type;
4073 -- Start of processing for Maybe_Primitive_Operation
4076 if not Comes_From_Source (S) then
4079 elsif (Ekind (Current_Scope) = E_Package
4080 and then not In_Package_Body (Current_Scope))
4083 -- For function, check return type
4085 if Ekind (S) = E_Function then
4086 B_Typ := Base_Type (Etype (S));
4088 if Scope (B_Typ) = Current_Scope then
4089 Set_Has_Primitive_Operations (B_Typ);
4090 Check_Private_Overriding (B_Typ);
4094 -- For all subprograms, check formals
4096 Formal := First_Formal (S);
4097 while Present (Formal) loop
4098 if Ekind (Etype (Formal)) = E_Anonymous_Access_Type then
4099 F_Typ := Designated_Type (Etype (Formal));
4101 F_Typ := Etype (Formal);
4104 B_Typ := Base_Type (F_Typ);
4106 if Scope (B_Typ) = Current_Scope then
4107 Set_Has_Primitive_Operations (B_Typ);
4108 Check_Private_Overriding (B_Typ);
4111 Next_Formal (Formal);
4114 end Maybe_Primitive_Operation;
4116 -- Start of processing for New_Overloaded_Entity
4120 Enter_Overloaded_Entity (S);
4121 Check_Dispatching_Operation (S, Empty);
4122 Maybe_Primitive_Operation;
4124 elsif not Is_Overloadable (E) then
4126 -- Check for spurious conflict produced by a subprogram that has the
4127 -- same name as that of the enclosing generic package. The conflict
4128 -- occurs within an instance, between the subprogram and the renaming
4129 -- declaration for the package. After the subprogram, the package
4130 -- renaming declaration becomes hidden.
4132 if Ekind (E) = E_Package
4133 and then Present (Renamed_Object (E))
4134 and then Renamed_Object (E) = Current_Scope
4135 and then Nkind (Parent (Renamed_Object (E))) =
4136 N_Package_Specification
4137 and then Present (Generic_Parent (Parent (Renamed_Object (E))))
4140 Set_Is_Immediately_Visible (E, False);
4141 Enter_Overloaded_Entity (S);
4142 Set_Homonym (S, Homonym (E));
4143 Check_Dispatching_Operation (S, Empty);
4145 -- If the subprogram is implicit it is hidden by the previous
4146 -- declaration. However if it is dispatching, it must appear in
4147 -- the dispatch table anyway, because it can be dispatched to
4148 -- even if it cannot be called directly.
4150 elsif Present (Alias (S))
4151 and then not Comes_From_Source (S)
4153 Set_Scope (S, Current_Scope);
4155 if Is_Dispatching_Operation (Alias (S)) then
4156 Check_Dispatching_Operation (S, Empty);
4162 Error_Msg_Sloc := Sloc (E);
4163 Error_Msg_N ("& conflicts with declaration#", S);
4165 -- Useful additional warning.
4167 if Is_Generic_Unit (E) then
4168 Error_Msg_N ("\previous generic unit cannot be overloaded", S);
4175 -- E exists and is overloadable. Determine whether S is the body
4176 -- of E, a new overloaded entity with a different signature, or
4177 -- an error altogether.
4179 while Present (E) loop
4180 if Scope (E) /= Current_Scope then
4183 elsif Type_Conformant (E, S) then
4185 -- If the old and new entities have the same profile and
4186 -- one is not the body of the other, then this is an error,
4187 -- unless one of them is implicitly declared.
4189 -- There are some cases when both can be implicit, for example
4190 -- when both a literal and a function that overrides it are
4191 -- inherited in a derivation, or when an inhertited operation
4192 -- of a tagged full type overrides the ineherited operation of
4193 -- a private extension. Ada 83 had a special rule for the
4194 -- the literal case. In Ada95, the later implicit operation
4195 -- hides the former, and the literal is always the former.
4196 -- In the odd case where both are derived operations declared
4197 -- at the same point, both operations should be declared,
4198 -- and in that case we bypass the following test and proceed
4199 -- to the next part (this can only occur for certain obscure
4200 -- cases involving homographs in instances and can't occur for
4201 -- dispatching operations ???). Note that the following
4202 -- condition is less than clear. For example, it's not at
4203 -- all clear why there's a test for E_Entry here. ???
4205 if Present (Alias (S))
4206 and then (No (Alias (E))
4207 or else Comes_From_Source (E)
4208 or else Is_Dispatching_Operation (E))
4210 (Ekind (E) = E_Entry
4211 or else Ekind (E) /= E_Enumeration_Literal)
4213 -- When an derived operation is overloaded it may be due
4214 -- to the fact that the full view of a private extension
4215 -- re-inherits. It has to be dealt with.
4217 if Is_Package (Current_Scope)
4218 and then In_Private_Part (Current_Scope)
4220 Check_Operation_From_Private_View (S, E);
4223 -- In any case the implicit operation remains hidden by
4224 -- the existing declaration.
4228 -- Within an instance, the renaming declarations for
4229 -- actual subprograms may become ambiguous, but they do
4230 -- not hide each other.
4232 elsif Ekind (E) /= E_Entry
4233 and then not Comes_From_Source (E)
4234 and then not Is_Generic_Instance (E)
4235 and then (Present (Alias (E))
4236 or else Is_Intrinsic_Subprogram (E))
4237 and then (not In_Instance
4238 or else No (Parent (E))
4239 or else Nkind (Unit_Declaration_Node (E)) /=
4240 N_Subprogram_Renaming_Declaration)
4242 -- A subprogram child unit is not allowed to override
4243 -- an inherited subprogram (10.1.1(20)).
4245 if Is_Child_Unit (S) then
4247 ("child unit overrides inherited subprogram in parent",
4252 if Is_Non_Overriding_Operation (E, S) then
4253 Enter_Overloaded_Entity (S);
4254 if not Present (Derived_Type)
4255 or else Is_Tagged_Type (Derived_Type)
4257 Check_Dispatching_Operation (S, Empty);
4263 -- E is a derived operation or an internal operator which
4264 -- is being overridden. Remove E from further visibility.
4265 -- Furthermore, if E is a dispatching operation, it must be
4266 -- replaced in the list of primitive operations of its type
4267 -- (see Override_Dispatching_Operation).
4273 Prev := First_Entity (Current_Scope);
4275 while Present (Prev)
4276 and then Next_Entity (Prev) /= E
4281 -- It is possible for E to be in the current scope and
4282 -- yet not in the entity chain. This can only occur in a
4283 -- generic context where E is an implicit concatenation
4284 -- in the formal part, because in a generic body the
4285 -- entity chain starts with the formals.
4288 (Present (Prev) or else Chars (E) = Name_Op_Concat);
4290 -- E must be removed both from the entity_list of the
4291 -- current scope, and from the visibility chain
4293 if Debug_Flag_E then
4294 Write_Str ("Override implicit operation ");
4295 Write_Int (Int (E));
4299 -- If E is a predefined concatenation, it stands for four
4300 -- different operations. As a result, a single explicit
4301 -- declaration does not hide it. In a possible ambiguous
4302 -- situation, Disambiguate chooses the user-defined op,
4303 -- so it is correct to retain the previous internal one.
4305 if Chars (E) /= Name_Op_Concat
4306 or else Ekind (E) /= E_Operator
4308 -- For nondispatching derived operations that are
4309 -- overridden by a subprogram declared in the private
4310 -- part of a package, we retain the derived subprogram
4311 -- but mark it as not immediately visible. If the
4312 -- derived operation was declared in the visible part
4313 -- then this ensures that it will still be visible
4314 -- outside the package with the proper signature
4315 -- (calls from outside must also be directed to this
4316 -- version rather than the overriding one, unlike the
4317 -- dispatching case). Calls from inside the package
4318 -- will still resolve to the overriding subprogram
4319 -- since the derived one is marked as not visible
4320 -- within the package.
4322 -- If the private operation is dispatching, we achieve
4323 -- the overriding by keeping the implicit operation
4324 -- but setting its alias to be the overring one. In
4325 -- this fashion the proper body is executed in all
4326 -- cases, but the original signature is used outside
4329 -- If the overriding is not in the private part, we
4330 -- remove the implicit operation altogether.
4332 if Is_Private_Declaration (S) then
4334 if not Is_Dispatching_Operation (E) then
4335 Set_Is_Immediately_Visible (E, False);
4338 -- work done in Override_Dispatching_Operation.
4344 -- Find predecessor of E in Homonym chain.
4346 if E = Current_Entity (E) then
4349 Prev_Vis := Current_Entity (E);
4350 while Homonym (Prev_Vis) /= E loop
4351 Prev_Vis := Homonym (Prev_Vis);
4355 if Prev_Vis /= Empty then
4357 -- Skip E in the visibility chain
4359 Set_Homonym (Prev_Vis, Homonym (E));
4362 Set_Name_Entity_Id (Chars (E), Homonym (E));
4365 Set_Next_Entity (Prev, Next_Entity (E));
4367 if No (Next_Entity (Prev)) then
4368 Set_Last_Entity (Current_Scope, Prev);
4374 Enter_Overloaded_Entity (S);
4376 if Is_Dispatching_Operation (E) then
4377 -- An overriding dispatching subprogram inherits
4378 -- the convention of the overridden subprogram
4381 Set_Convention (S, Convention (E));
4383 Check_Dispatching_Operation (S, E);
4385 Check_Dispatching_Operation (S, Empty);
4388 Maybe_Primitive_Operation (Overriding => True);
4389 goto Check_Inequality;
4392 -- Apparent redeclarations in instances can occur when two
4393 -- formal types get the same actual type. The subprograms in
4394 -- in the instance are legal, even if not callable from the
4395 -- outside. Calls from within are disambiguated elsewhere.
4396 -- For dispatching operations in the visible part, the usual
4397 -- rules apply, and operations with the same profile are not
4400 elsif (In_Instance_Visible_Part
4401 and then not Is_Dispatching_Operation (E))
4402 or else In_Instance_Not_Visible
4406 -- Here we have a real error (identical profile)
4409 Error_Msg_Sloc := Sloc (E);
4411 -- Avoid cascaded errors if the entity appears in
4412 -- subsequent calls.
4414 Set_Scope (S, Current_Scope);
4416 Error_Msg_N ("& conflicts with declaration#", S);
4418 if Is_Generic_Instance (S)
4419 and then not Has_Completion (E)
4422 ("\instantiation cannot provide body for it", S);
4436 -- On exit, we know that S is a new entity
4438 Enter_Overloaded_Entity (S);
4439 Maybe_Primitive_Operation;
4441 -- If S is a derived operation for an untagged type then
4442 -- by definition it's not a dispatching operation (even
4443 -- if the parent operation was dispatching), so we don't
4444 -- call Check_Dispatching_Operation in that case.
4446 if not Present (Derived_Type)
4447 or else Is_Tagged_Type (Derived_Type)
4449 Check_Dispatching_Operation (S, Empty);
4453 -- If this is a user-defined equality operator that is not
4454 -- a derived subprogram, create the corresponding inequality.
4455 -- If the operation is dispatching, the expansion is done
4456 -- elsewhere, and we do not create an explicit inequality
4459 <<Check_Inequality>>
4460 if Chars (S) = Name_Op_Eq
4461 and then Etype (S) = Standard_Boolean
4462 and then Present (Parent (S))
4463 and then not Is_Dispatching_Operation (S)
4465 Make_Inequality_Operator (S);
4468 end New_Overloaded_Entity;
4470 ---------------------
4471 -- Process_Formals --
4472 ---------------------
4474 procedure Process_Formals
4476 Related_Nod : Node_Id)
4478 Param_Spec : Node_Id;
4480 Formal_Type : Entity_Id;
4484 function Is_Class_Wide_Default (D : Node_Id) return Boolean;
4485 -- Check whether the default has a class-wide type. After analysis
4486 -- the default has the type of the formal, so we must also check
4487 -- explicitly for an access attribute.
4489 ---------------------------
4490 -- Is_Class_Wide_Default --
4491 ---------------------------
4493 function Is_Class_Wide_Default (D : Node_Id) return Boolean is
4495 return Is_Class_Wide_Type (Designated_Type (Etype (D)))
4496 or else (Nkind (D) = N_Attribute_Reference
4497 and then Attribute_Name (D) = Name_Access
4498 and then Is_Class_Wide_Type (Etype (Prefix (D))));
4499 end Is_Class_Wide_Default;
4501 -- Start of processing for Process_Formals
4504 -- In order to prevent premature use of the formals in the same formal
4505 -- part, the Ekind is left undefined until all default expressions are
4506 -- analyzed. The Ekind is established in a separate loop at the end.
4508 Param_Spec := First (T);
4510 while Present (Param_Spec) loop
4512 Formal := Defining_Identifier (Param_Spec);
4513 Enter_Name (Formal);
4515 -- Case of ordinary parameters
4517 if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then
4518 Find_Type (Parameter_Type (Param_Spec));
4519 Ptype := Parameter_Type (Param_Spec);
4521 if Ptype = Error then
4525 Formal_Type := Entity (Ptype);
4527 if Ekind (Formal_Type) = E_Incomplete_Type
4528 or else (Is_Class_Wide_Type (Formal_Type)
4529 and then Ekind (Root_Type (Formal_Type)) =
4532 if Nkind (Parent (T)) /= N_Access_Function_Definition
4533 and then Nkind (Parent (T)) /= N_Access_Procedure_Definition
4535 Error_Msg_N ("invalid use of incomplete type", Param_Spec);
4538 elsif Ekind (Formal_Type) = E_Void then
4539 Error_Msg_NE ("premature use of&",
4540 Parameter_Type (Param_Spec), Formal_Type);
4543 -- An access formal type
4547 Access_Definition (Related_Nod, Parameter_Type (Param_Spec));
4550 Set_Etype (Formal, Formal_Type);
4552 Default := Expression (Param_Spec);
4554 if Present (Default) then
4555 if Out_Present (Param_Spec) then
4557 ("default initialization only allowed for IN parameters",
4561 -- Do the special preanalysis of the expression (see section on
4562 -- "Handling of Default Expressions" in the spec of package Sem).
4564 Analyze_Default_Expression (Default, Formal_Type);
4566 -- Check that the designated type of an access parameter's
4567 -- default is not a class-wide type unless the parameter's
4568 -- designated type is also class-wide.
4570 if Ekind (Formal_Type) = E_Anonymous_Access_Type
4571 and then Is_Class_Wide_Default (Default)
4572 and then not Is_Class_Wide_Type (Designated_Type (Formal_Type))
4575 ("access to class-wide expression not allowed here", Default);
4583 -- Now set the kind (mode) of each formal
4585 Param_Spec := First (T);
4587 while Present (Param_Spec) loop
4588 Formal := Defining_Identifier (Param_Spec);
4589 Set_Formal_Mode (Formal);
4591 if Ekind (Formal) = E_In_Parameter then
4592 Set_Default_Value (Formal, Expression (Param_Spec));
4594 if Present (Expression (Param_Spec)) then
4595 Default := Expression (Param_Spec);
4597 if Is_Scalar_Type (Etype (Default)) then
4599 (Parameter_Type (Param_Spec)) /= N_Access_Definition
4601 Formal_Type := Entity (Parameter_Type (Param_Spec));
4604 Formal_Type := Access_Definition
4605 (Related_Nod, Parameter_Type (Param_Spec));
4608 Apply_Scalar_Range_Check (Default, Formal_Type);
4617 end Process_Formals;
4619 -------------------------
4620 -- Set_Actual_Subtypes --
4621 -------------------------
4623 procedure Set_Actual_Subtypes (N : Node_Id; Subp : Entity_Id) is
4624 Loc : constant Source_Ptr := Sloc (N);
4628 First_Stmt : Node_Id := Empty;
4629 AS_Needed : Boolean;
4632 Formal := First_Formal (Subp);
4633 while Present (Formal) loop
4634 T := Etype (Formal);
4636 -- We never need an actual subtype for a constrained formal.
4638 if Is_Constrained (T) then
4641 -- If we have unknown discriminants, then we do not need an
4642 -- actual subtype, or more accurately we cannot figure it out!
4643 -- Note that all class-wide types have unknown discriminants.
4645 elsif Has_Unknown_Discriminants (T) then
4648 -- At this stage we have an unconstrained type that may need
4649 -- an actual subtype. For sure the actual subtype is needed
4650 -- if we have an unconstrained array type.
4652 elsif Is_Array_Type (T) then
4655 -- The only other case which needs an actual subtype is an
4656 -- unconstrained record type which is an IN parameter (we
4657 -- cannot generate actual subtypes for the OUT or IN OUT case,
4658 -- since an assignment can change the discriminant values.
4659 -- However we exclude the case of initialization procedures,
4660 -- since discriminants are handled very specially in this context,
4661 -- see the section entitled "Handling of Discriminants" in Einfo.
4662 -- We also exclude the case of Discrim_SO_Functions (functions
4663 -- used in front end layout mode for size/offset values), since
4664 -- in such functions only discriminants are referenced, and not
4665 -- only are such subtypes not needed, but they cannot always
4666 -- be generated, because of order of elaboration issues.
4668 elsif Is_Record_Type (T)
4669 and then Ekind (Formal) = E_In_Parameter
4670 and then Chars (Formal) /= Name_uInit
4671 and then not Is_Discrim_SO_Function (Subp)
4675 -- All other cases do not need an actual subtype
4681 -- Generate actual subtypes for unconstrained arrays and
4682 -- unconstrained discriminated records.
4685 Decl := Build_Actual_Subtype (T, Formal);
4687 if Nkind (N) = N_Accept_Statement then
4688 if Present (Handled_Statement_Sequence (N)) then
4690 First (Statements (Handled_Statement_Sequence (N)));
4691 Prepend (Decl, Statements (Handled_Statement_Sequence (N)));
4692 Mark_Rewrite_Insertion (Decl);
4694 -- If the accept statement has no body, there will be
4695 -- no reference to the actuals, so no need to compute
4702 Prepend (Decl, Declarations (N));
4703 Mark_Rewrite_Insertion (Decl);
4708 -- We need to freeze manually the generated type when it is
4709 -- inserted anywhere else than in a declarative part.
4711 if Present (First_Stmt) then
4712 Insert_List_Before_And_Analyze (First_Stmt,
4713 Freeze_Entity (Defining_Identifier (Decl), Loc));
4716 Set_Actual_Subtype (Formal, Defining_Identifier (Decl));
4719 Next_Formal (Formal);
4721 end Set_Actual_Subtypes;
4723 ---------------------
4724 -- Set_Formal_Mode --
4725 ---------------------
4727 procedure Set_Formal_Mode (Formal_Id : Entity_Id) is
4728 Spec : constant Node_Id := Parent (Formal_Id);
4731 -- Note: we set Is_Known_Valid for IN parameters and IN OUT parameters
4732 -- since we ensure that corresponding actuals are always valid at the
4733 -- point of the call.
4735 if Out_Present (Spec) then
4737 if Ekind (Scope (Formal_Id)) = E_Function
4738 or else Ekind (Scope (Formal_Id)) = E_Generic_Function
4740 Error_Msg_N ("functions can only have IN parameters", Spec);
4741 Set_Ekind (Formal_Id, E_In_Parameter);
4743 elsif In_Present (Spec) then
4744 Set_Ekind (Formal_Id, E_In_Out_Parameter);
4747 Set_Ekind (Formal_Id, E_Out_Parameter);
4748 Set_Not_Source_Assigned (Formal_Id);
4752 Set_Ekind (Formal_Id, E_In_Parameter);
4755 Set_Mechanism (Formal_Id, Default_Mechanism);
4756 Set_Formal_Validity (Formal_Id);
4757 end Set_Formal_Mode;
4759 -------------------------
4760 -- Set_Formal_Validity --
4761 -------------------------
4763 procedure Set_Formal_Validity (Formal_Id : Entity_Id) is
4765 -- If in full validity checking mode, then we can assume that
4766 -- an IN or IN OUT parameter is valid (see Exp_Ch5.Expand_Call)
4768 if not Validity_Checks_On then
4771 elsif Ekind (Formal_Id) = E_In_Parameter
4772 and then Validity_Check_In_Params
4774 Set_Is_Known_Valid (Formal_Id, True);
4776 elsif Ekind (Formal_Id) = E_In_Out_Parameter
4777 and then Validity_Check_In_Out_Params
4779 Set_Is_Known_Valid (Formal_Id, True);
4781 end Set_Formal_Validity;
4783 ------------------------
4784 -- Subtype_Conformant --
4785 ------------------------
4787 function Subtype_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
4791 Check_Conformance (New_Id, Old_Id, Subtype_Conformant, False, Result);
4793 end Subtype_Conformant;
4795 ---------------------
4796 -- Type_Conformant --
4797 ---------------------
4799 function Type_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is
4803 Check_Conformance (New_Id, Old_Id, Type_Conformant, False, Result);
4805 end Type_Conformant;
4807 -------------------------------
4808 -- Valid_Operator_Definition --
4809 -------------------------------
4811 procedure Valid_Operator_Definition (Designator : Entity_Id) is
4814 Id : constant Name_Id := Chars (Designator);
4818 F := First_Formal (Designator);
4820 while Present (F) loop
4823 if Present (Default_Value (F)) then
4825 ("default values not allowed for operator parameters",
4832 -- Verify that user-defined operators have proper number of arguments
4833 -- First case of operators which can only be unary
4836 or else Id = Name_Op_Abs
4840 -- Case of operators which can be unary or binary
4842 elsif Id = Name_Op_Add
4843 or Id = Name_Op_Subtract
4845 N_OK := (N in 1 .. 2);
4847 -- All other operators can only be binary
4855 ("incorrect number of arguments for operator", Designator);
4859 and then Base_Type (Etype (Designator)) = Standard_Boolean
4860 and then not Is_Intrinsic_Subprogram (Designator)
4863 ("explicit definition of inequality not allowed", Designator);
4865 end Valid_Operator_Definition;